Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/23/12

AREA FORECAST DISCUSSION

NWS ALBANY NY

356 AM EDT TUE AUG 21 2012

.SYNOPSIS...
AN UPPER LEVEL TROUGH PASSING THROUGH THE REGION WILL
ALLOW FOR SOME ISOLATED SHOWERS TODAY AND TOMORROW...MAINLY FOR
AREAS TO THE SOUTH OF THE CAPITAL REGION. HIGH PRESSURE WILL BUILD
INTO THE NORTHEAST TO END THE WEEK...WITH FAIR WEATHER AND
TEMPERATURES MODERATING TO SLIGHTLY ABOVE NORMAL.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 355 AM EDT...A SURFACE BOUNDARY WAS STALLED FROM THE DEEP
SOUTH NORTHEASTWARD TO THE CAROLINA COAST TO OFFSHORE NEW ENGLAND.
ALOFT...A TROUGH WAS CARVED OUT ACROSS THE EASTERN CONUS...WITH
THE POSITIVELY TILTED TROUGH AXIS ACROSS THE OHIO VALLEY. WITH A
130+ KT JET STREAK AT 250 HPA POSITIONED OVER NEW ENGLAND...A
LARGE AMOUNT OF MID AND HIGH LEVEL CLOUDINESS WAS IN PLACE ACROSS
OUR EASTERN ZONES THIS MORNING. AS THE MORNING PROGRESSES...THESE
CLOUDS SHOULD THIN OUT AS THE JET STREAK CONTINUES TO LIFT
NORTHEASTWARD INTO CANADA...ALLOWING FOR A PARTLY TO MOSTLY SUNNY
SKY ACROSS THE AREA FOR TODAY.

THE TROUGH AXIS WILL ONLY SLOWLY BE MOVING EASTWARD. AS A
RESULT...THERE ISN/T MUCH LARGE SCALE LIFT ACROSS OUR AREA
TODAY...AS WE WILL NOT BE IN ANY FAVORABLE QUADS OF THE DEPARTING
JET STREAK EITHER. WITH PWAT VALUES LESS THAN AN INCH AND TD
VALUES ONLY IN THE 40S AND 50S...AND A FORECASTED WEAK CAP AROUND
700 HPA...IT WILL BE DIFFICULT TO SEE MUCH IN THE WAY OF
SHOWERS/TSTORMS TODAY. THE 00 UTC NAM/GFS/UKMET/GGEM/ECMWF ALL
POINT TOWARDS A DRY FORECAST FOR TODAY...WITH MOS POPS RATHER LOW
AS WELL. STILL...WILL GO WITH ISOLD RAIN SHOWERS FOR THE
CATSKILLS...SOUTHERN BERKSHIRES...NW CT...AND ADJACENT AREAS...IN
CASE DIFFERENTIAL HEATING IN THE HIGH TERRAIN CAN POP A
BRIEF...WEAK SHOWER FOR THE AFTN HOURS. THE LATEST 3KM HRRR DOES
SHOW A FEW WEAK ISOLD PULSE SHOWERS OVER THE HIGH TERRAIN
DEVELOPING BY AROUND 18Z.

WITH CAPE VALUES FORECASTED TO ONLY BE A FEW HUNDRED J/KG...LI
VALUES FORECATED TO BE MAINLY ABOVE ZERO AND SUCH SPARSE COVERAGE
OF ACTIVITY...WILL NOT INCLUDE ANY THUNDER AT THIS TIME.

TEMPS TODAY LOOK A TAD WARMER THAN YESTERDAY WITH A BIT MORE
SUNSHINE EXPECTED. VALLEY AREAS LOOK TO SEE UPPER 70S TO LOW
80S...WITH LOWER TO MIDDLE 70S FOR THE HIGH TERRAIN.

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
WITH THE LOSS OF DAYTIME HEATING...ANY SHOWERS WILL END BY SUNSET
AND SKIES LOOK NEARLY CLEAR FOR THE OVERNIGHT HOURS. MIN TEMPS
WILL RANGE FROM THE MID 40S TO THE MID 50S.

ON WEDNESDAY...THE TROUGH AXIS WILL BE LIFTING NORTHEASTWARD
ACROSS SOUTHERN PARTS OF OUR AREA. PWAT AND TD VALUES WILL BE A
LITTLE HIGHER FOR WEDNESDAY THAN TUESDAY. DESPITE THE UPPER TROUGH
PASSING TO OUR SOUTH...SFC HIGH PRESSURE CENTERED OVER THE
CAPITAL REGION WILL PROVIDE SUBSIDENCE...AND WITH A WEAK CAP
ALOFT...WE DON/T EXPECT MUCH PRECIP TO DEVELOP. WE WILL ONLY GO WITH
SLIGHT CHC FOR SHOWERS ACROSS THE CATSKILLS FOR THE AFTN HOURS AT
THIS TIME. THE 00 GEFS AGREES WITH THE CATSKILLS HAVING THE BEST
CHANCE OF ANYWHERE OF SEEING SOME MEASUREABLE PRECIP /EVEN IF IT/S
ONLY A FEW HUNDREDTHS OF AN INCH/. AGAIN...INSTABILITY LOOKS
MEAGER...SO NO MENTION OF THUNDER. MAX TEMPS MAY BE A DEGREE OR
TWO WARMER THAN TUESDAY FOR MOST PLACES.

THE UPPER TROUGH WILL LIFT OUT FOR WEDNESDAY NIGHT AND THE FLOW
WILL BECOME ZONAL FOR WED NIGHT INTO THURSDAY. AT THE SURFACE...HIGH
PRESSURE WILL REMAIN IN CONTROL. THIS WILL KEEP IT RAIN FREE
ACROSS THE REGION. IN ADDITION...TEMPS WILL ONCE AGAIN BE A LITTLE
WARMER ON THURSDAY...WITH MID 80S FOR VALLEY AREAS...AND DEWPOINT
VALUES SNEAKING BACK UP TO AROUND 60 F.

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A RETURN TOWARD MORE AUGUST-LIKE WEATHER AS HEIGHTS CONTINUE TO RISE
ALONG WITH AN INCREASING MOIST SOUTHERLY FLOW. THERE ARE SOME
SUBTLE HINTS IN THIS MORNINGS MODEL SUITE OF AN EVOLVING CUT OFF
UPPER LOW OVER OR JUST OFFSHORE OF THE MID ATLANTIC REGION. THIS
FORECAST FEATURE IS ALONG THE STALLED OUT FRONTAL BOUNDARY IN THE
VICINITY OF THE GULF STREAM WITH PLACEMENT QUITE DIFFERENT FROM THE
GFS TO THE ECMWF. OUTSIDE OF THIS FEATURE...A WARM FRONT OR THE
LEADING EDGE OF HIGHER THETA-E AIR APPROACHES THIS WEEKEND TOO...
WHICH WE WILL INTRODUCE A SLIGHT CHANCE POPS FOR CONVECTION.

AS 850MB TEMPS REBOUND BACK TOWARD THE MIDDLE TEENS ALONG WITH
DEWPOINTS BACK TOWARD AND EVENTUALLY ABOVE 60F...SURFACE
TEMPERATURES WILL REBOUND BACK INTO THE 80S FOR MANY VALLEY
LOCATIONS WITH OVERNIGHT LOWS SLOWLY CLIMBING BACK INTO THE LOWER
60S.

LOOKING FURTHER AHEAD INTO THE START OF NEXT WEEK...MODELS DIVERGE
SIGNIFICANTLY AS THE GFS REMAINS THE MOST PROGRESSIVE WITH A FRONT
APPROACHING WHILE THE ECMWF IS MORE PRONOUNCED AND SLOWER WITH THE
POTENTIAL FRONT. MEANWHILE...WE WILL BE WATCHING THE TROPICS WITH
GREAT INTEREST WITH THE APPROACH OF A SOON TO BE NAMED SYSTEM ACROSS
THE CENTRAL TROPICAL ATLANTIC...PLEASE REFER TO THE LATEST FORECAST
GUIDANCE FROM THE NATIONAL HURRICANE CENTER.

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
CHALLENGING FORECAST THE NEXT 6-9 HRS AS IT WILL BE RACE BETWEEN
COLLAPSING DEWPOINT DEPRESSIONS AND THE DEPARTURE OF THE BKN-OVC MID
LEVEL CLOUD DECK. WHERE ENOUGH BREAKS IN THE CLOUDS DO
OCCUR...THERE IS A HIGH POTENTIAL FOR IFR TO LIFR CONDITIONS TO
DEVELOP WITH FOG AND LOW CIGS. AT THE PRESENT TIME...WE FEEL KGFL
STANDS THE BEST CHANCE FOR THOSE LOWER THRESHOLDS AND WE FORECAST
THOSE CONDITIONS TO BE MET. ELSEWHERE...WHERE RAIN WAS MORE OF AN
IMPACT...EXPECTATIONS ARE FOR AT LEAST MVFR CONDITIONS DUE TO
MIST/BR WITH THE CHANCE FOR IFR CONDITIONS AS WE WILL PLACE TEMPO
GROUPS FOR THIS POTENTIAL.

ONCE SUNSHINE OCCURS...ANY FOG OR LOW STRATUS WILL QUICKLY DISSIPATE
AND FLIGHT CONDITIONS RETURN BACK TO VFR.

WINDS WILL BE RATHER LIGHT...LESS THAN 10 KTS...THROUGH THE FORECAST
PERIOD.

OUTLOOK...
WED-SAT...MAINLY VFR CONDITIONS. CHC FOR LATE NT/EARLY AM BR/FOG.

.FIRE WEATHER...
AN UPPER LEVEL TROUGH WILL SLOWLY MOVE EAST FROM THE OHIO VALLEY...
AND BRING SOME ISOLATED RAIN SHOWERS OVER SOUTHERN PARTS OF THE
AREA FOR TODAY AND TOMORROW...ALTHOUGH MOST AREAS WILL BE DRY FOR
MUCH OF THE TIME...AND RAINFALL AMOUNTS WILL BE LIGHT. HIGH PRESSURE
WILL RETURN TO THE REGION BY THURSDAY WITH SEASONABLE
TEMPERATURES.

RH VALUES WILL DROP TO 30-40 PERCENT THIS AFTERNOON. RH VALUES
WILL RECOVER TO NEAR 100 PERCENT TONIGHT...AND DROP TO BETWEEN
30-40 PERCENT WEDNESDAY AFTERNOON.

OVER THE NEXT FEW DAYS...SURFACE WINDS WILL BE LIGHT AND VARIABLE.

.HYDROLOGY...
NO HYDRO PROBLEMS ARE EXPECTED FOR THE NEXT FIVE DAYS.

ISOLATED RAIN SHOWERS ARE POSSIBLE OVER THE CATSKILLS TODAY AND
TOMORROW. A FEW OF THESE SHOWERS MAY DRIFT INTO THE MID HUDSON
VALLEY...BERKSHIRES...TACONICS...AND NW CT. WITH PWAT VALUES RATHER LOW
/GENERALLY LESS THAN 1.00 INCH/...RAINFALL WILL NOT BE VERY
INTENSE...AND ANY RAINFALL AMOUNTS WILL BE LIGHT. AS A
RESULT...THIS RAIN WILL HAVE LITTLE TO NO EFFECT ON AREA RIVERS AND
STREAMS.

FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.

$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS

AREA FORECAST DISCUSSION

NWS MIAMI FL

209 PM EDT TUE AUG 21 2012

.DISCUSSION...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS
THE INTERIOR AND PUSH TOWARDS THE NORTHEAST SECTIONS OF THE CWA THIS
AFTERNOON AND INTO THE EVENING UNDER THE SOUTHWEST FLOW ALOFT. A
FEW STORMS COULD BE STRONG...WITH THE MAIN THREAT BEING STRONG
WINDS OF 40 TO 50 MPH. THE HRRR IS SHOWING THAT A LINE OF STORMS
MAY MOVE ACROSS THE EASTERN GULF AND INTO CENTRAL FLORIDA...WITH
THE TAIL END OF THIS LINE OF SHOWERS AND THUNDERSTORMS POSSIBLY
MOVING INTO THE LOCAL GULF WATERS AND PORTIONS OF THE NORTHWEST
AFTER 00Z. THIS IS CONSISTENT WITH THE 12Z GFS SHOWING A PIECE OF
ENERGY ROTATING AROUND THE BASE OF THE TROUGH AND ACROSS CENTRAL
FLORIDA OVERNIGHT. SO WILL KEEP 20-30 POPS FOR THIS REGION.

THE UPPER TROUGH ALONG THE EASTERN SEABOARD WILL BEGIN TO FILL AND
LIFT TO THE NORTHEAST TONIGHT AND WEDNESDAY...BUT A WEAKNESS WILL
REMAIN OVER THE GULF AND THE WESTERN ATLANTIC THROUGH THE WEEKEND.
AT THE SURFACE...THE QUASI-STATIONARY FRONT OVER NORTH FLORIDA
WILL SLOWLY DRIFT SOUTHWARD TONIGHT INTO WEDNESDAY AND THEN BEGIN
TO WASH OUT AND DRIFT NORTHWARD INTO THURSDAY. THE SUBTROPICAL
RIDGE OVER THE WESTERN ATLANTIC WILL MOVE NORTHWARD AND THE DRY
AIR AND HAZE OVER THE BAHAMAS IS EXPECTED TO PUSH INTO SOUTH
FLORIDA ON WEDNESDAY AND THURSDAY. IN ADDITION...THE LOW/MID LEVEL
FLOW WILL SHIFT FROM THE SOUTHWEST TO THE EAST AND SOUTHEAST BY
THURSDAY.

WITH PWATS FALLING TO AROUND 1.5 INCHES ON WEDNESDAY ALONG THE
SOUTHEAST COAST...ONLY MINIMAL RAIN CHANCES ARE EXPECTED.
STEERING FLOW WILL PUSH STORMS SLOWLY TO THE NORTH ON WEDNESDAY.
HIGHER MOISTURE WILL ALSO LINGER AROUND THE LAKE ON WEDNESDAY...SO
THERE WILL STILL BE A CHANCE OF STORMS FOR THE LAKE OKEECHOBEE
REGION. MODEL SOUNDINGS ARE SHOWING RELATIVELY STEEP LAPSE RATES
ABOVE THE INVERSION AND STRONG STORMS AND POSSIBLY AN ISOLATED
SEVERE STORM CANNOT BE RULED OUT ON WEDNESDAY. HEAT INDICES WILL
BE THE TYPICAL 100-108F FOR THIS TIME OF YEAR...WITH THE HIGHEST
READINGS ACROSS THE INTERIOR.

EVEN DRIER AIR IS EXPECTED TO MOVE INTO THE REGION ON
THURSDAY...WITH PWATS ACROSS THE REGION DROPPING TO 1.3-1.6 INCHES.
WITH THE FLOW SHIFTING TO THE EAST AND SOUTHEAST...EXPECT THE EAST
COAST TO MAINLY STAY DRY...WITH ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS THE INTERIOR AND TOWARDS THE GULF COAST.

FOR FRIDAY INTO SATURDAY...THE PRESSURE GRADIENT MAY BEGIN TO
TIGHTEN AS TROPICAL DEPRESSION NINE MOVES NEAR HAITI AND EASTERN
CUBA. SO SOMEWHAT BREEZIER EASTERLY FLOW COULD BEGIN ON FRIDAY AND
SATURDAY WITH AN INCREASE IN LOW LEVEL MOISTURE AND RAIN CHANCES.

IT IS STILL TOO EARLY TO DETERMINE THE IMPACTS OF TROPICAL
DEPRESSION NINE ON SOUTH FLORIDA OR THE SURROUNDING MARINE AREAS IN
THE LONG TERM. HOWEVER...THERE IS INCREASING POTENTIAL THAT SOUTH
FLORIDA AND/OR THE SURROUNDING MARINE AREAS COULD BE IMPACTED LATE
THIS WEEKEND INTO EARLY NEXT WEEK. SO NOW IS A GOOD TIME TO
REVIEW INDIVIDUAL TROPICAL CYCLONE PREPAREDNESS PLANS. FOR THE
LATEST INFORMATION REGARDING TROPICAL DEPRESSION NINE...CONTINUE
TO MONITOR THE LATEST FORECASTS FROM THE NATIONAL HURRICANE
CENTER.

.AVIATION...
A FEW THUNDERSTORMS COULD DEVELOP THIS AFTERNOON
MAINLY TOWARD KPBI AND KFXE, BUT EXPECT TO HAVE ACTIVITY CLOSE
ENOUGH TO THE REST OF THE ERN TERMINALS TO BE WORTH MENTIONING
VCTS IN TAFS. WL EXPECT ANY SHWR/TSTM TO REMAIN WELL AWAY FROM
KAPF AND NO AFFECT OPERATIONS. EVENING ACTIVITY SHOULD TAPER OFF
BY 00Z TONIGHT. SFC SHOULD REMAIN MOSTLY SE, ALTHOUGH BECOMING
LIGHT AND VARIABLE AFTER 00Z AND INCREASING AGAIN TO AROUND 8-10
KTS AFTER 13Z WEDNESDAY.

.MARINE...
A RIDGE OF HIGH PRESSURE WILL BE LOCATED OVER THE SOUTH FLORIDA
WATERS THROUGH THE MIDDLE OF THE WEEK BEFORE SHIFTING NORTH DURING
THE LATTER PART OF THE WEEK. THIS WILL LEAD TO WINDS OUT OF THE
SOUTH BECOMING EASTERLY LATE IN THE WEEK. THE PRESSURE GRADIENT IS
EXPECTED TO INCREASE FRIDAY AND SATURDAY AS TROPICAL DEPRESSION
NINE MOVES NEAR HAITI AND EASTERN CUBA. THE FORECAST FOR LATE THIS
WEEKEND BECOMES HIGHLY DEPENDENT ON THE EVOLUTION THIS TROPICAL
CYCLONE. THE FORECAST TRACK OF THIS POTENTIAL SYSTEM IS IN THE
GENERAL DIRECTION OF THE REGIONAL WATERS AND SHOULD BE CLOSELY
MONITORED BY ALL MARINE INTERESTS OVER THE COMING DAYS.

.FIRE WEATHER...
SOUTH TO SOUTHWEST WINDS WILL BE OVER SOUTH FLORIDA AGAIN ON
WEDNESDAY AS A HIGH PRESSURE RIDGE PERSISTS JUST SOUTH OF THE
AREA OVER THE KEYS AND FLORIDA STRAITS. ISOLATED TO SCATTERED
THUNDERSTORMS ARE EXPECTED TO DEVELOP IN THE AFTERNOON ON
WEDNESDAY BUT AFFECTING MAINLY THE INTERIOR AND THE LAKE
OKEECHOBEE REGION AS THE ACTIVITY WILL MOVE TO THE NORTHEAST. EAST
AND WEST COAST SEA BREEZES ARE EXPECTED TO DEVELOP LATE THIS
MORNING AND CONTINUE INTO THIS AFTERNOON ON WEDNESDAY. FLOW WILL
BECOME MORE EASTERLY ON THURSDAY AND STRENGTHEN FRIDAY INTO THE
WEEKEND AS THE PRESSURE GRADIENT INCREASES.

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 78 91 78 89 / 30 20 10 10
FORT LAUDERDALE 80 91 80 91 / 20 20 10 10
MIAMI 79 92 79 91 / 20 10 10 10
NAPLES 77 93 77 93 / 30 30 20 30

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&

DISCUSSION/MARINE/FIRE...84/AK
AVIATION/RADAR...47/RGH

EXTENDED FORECAST DISCUSSION AND CENTRAL REGION INITIALIZATION WITH

POPS ACROSS OUR WEST BY SUNDAY AND BEST CHANCES SUNDAY NIGHT AND

MONDAY. OTHERWISE...WILL NOT MAKE ANY CHANGES TO TEMPERATURES. HIGH
PRESSURE ACROSS THE EASTERN STATES WILL ALLOW RETURN FLOW WHICH
SHOULD BRING TEMPERATURES BACK UP TO NORMAL OR SLIGHTLY ABOVE NORMAL
IN THE 80S AT LEAST UNTIL FRONTAL PASSAGE MONDAY OR TUESDAY.

.AVIATION /DISCUSSION FOR 220000Z TAFS/...
ISSUED AT 620 PM EDT TUE AUG 21 2012

MVFR FOG IS EXPECTED AT ALL BUT KIND FOR A FEW HOURS
OVERNIGHT...OTHERWISE VFR CONDITIONS EXPECTED.

DIURNAL CU SHOULD BE ABOUT GONE BY TAF VALID TIME. HIGH PRESSURE
WILL BUILD IN DURING THE NIGHT. GROUND HAS DRIED OUT SOME...AND
DRIER AIR IS MOVING IN AS WELL. THUS DO NOT THINK FOG WILL BE AS BAD
AT KLAF AS THE PREVIOUS NIGHT. WILL GO PREDOMINANT MVFR FOR SEVERAL
HOURS THERE.

AT KHUF AND KBMG...AM LESS CONFIDENT IN FOG FORMATION...BUT WILL
KEEP CURRENT FORECAST OF A FEW HOURS OF MVFR FOG THERE. ADDITIONAL
CU WILL FORM WEDNESDAY. WINDS SHOULD REMAIN LESS THAN 10KT THROUGH
THE PERIOD.

.IND WATCHES/WARNINGS/ADVISORIES...NONE.

SYNOPSIS...NIELD
NEAR TERM...NIELD
SHORT TERM...NIELD
LONG TERM....MK
AVIATION...50

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

216 PM CDT TUE AUG 21 2012

...UPDATED FOR THE LONG TERM FORECAST...

.SYNOPSIS...
ISSUED AT 900 AM CDT TUE AUG 21 2012

THE 21.12Z 250 HPA RAOB MAP NETWORK SHOWED TWO JETS ACROSS NORTH AMERICA.
ONE AROUND 100 KT WAS LOCATED ACROSS THE PACIFIC NORTHWEST. ANOTHER
ONE THAT WAS FAIRLY STRONG FOR THIS TIME OF YEAR /145 KT/ WAS LOCATED
ACROSS NEW ENGLAND. AT 500 HPA, A SHORTWAVE TROF WAS JUST WEST OF OREGON
AND WASHINGTON. A 590 DM ANTICYCLONE WAS LOCATED OVER THE DESERT SOUTHWEST.
FINALLY, AN ELONGATED TROF EXTENDED FROM CENTRAL QUEBEC TO THE NORTHERN
GULF OF MEXICO. AT 700 HPA, TEMPS WERE IN THE 6 TO 7 DEG C RANGE ACROSS
KANSAS...BASICALLY NOT MUCH CHANGE FROM 24 HOURS AGO. THE IMPRESSIVE
COLD POOL FOR AUGUST WITH VALUES IN THE 0 TO -3 DEG C RANGE WERE LOCATED
ACROSS THE OHIO RIVER VALLEY AND NORTHEAST. AT 850 HPA, LOW DEWPOINT
DEPRESSIONS ACROSS THE TEXAS PANHANDLE WERE ASSOCIATED WITH PRECIP AND
LOW CLOUDS. ACROSS SW KANSAS, THE THERMODYNAMICS WAS FAIRLY WARM AND
DRY. THE WARMEST PLUME WITH TEMPS IN THE LOWER 20S DEG C WAS OBSERVED
ACROSS THE NORTHERN HIGH PLAINS. AT THE SFC, HIGH PRESSURE EXTENDED
ACROSS MUCH OF THE MIDWEST. WEAK RETURN FLOW WAS OBSERVED ACROSS THE
HIGH PLAINS. TROPICAL DEPRESSION NINE WAS LOCATED NEAR 15.2N 51.2W @ 21.09Z.

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 100 PM CDT TUE AUG 21 2012

TONIGHT:

THE SHORT TERM METEOROLOGICAL CONCERN IS WHAT TO DO WITH POPS FOR THIS
EVENING. MESOSCALE (NAM, WRF) AND GLOBAL MODELS (GFS, ECMWF) PAINT DOUBT
ON CONVECTIVE PROSPECTS FOR THE EVENING. THIS IS A RESULT OF THE FACT
THAT THE UPPER LEVEL JET/WAVE IS EAST OF THE REGION AND CONVERGENCE
AT THE SURFACE IS FORECAST TO BE WEAK. 850 HPA THETA-E ADVECTION IS
FORECAST TO REMAIN WEAK AS WELL. RECENT HRRR RUNS HAS BEEN INDICATING
ISOLATED ACTIVITY ACROSS THE WESTERN ZONES THIS EVENING BUT THIS MODEL
HAS BEEN TRENDING DOWNWARD OVERALL IN THE LAST SEVERAL RUNS. AS A RESULT,
HAVE REMOVED WX FROM THE GRIDS AND GOING WITH A DRY FORECAST FOR THIS
EVENING. SOUTHERLY WINDS WILL CONTINUE THROUGH THE OVERNIGHT WITH MODERATE
DEWPOINTS AS WELL. LOOK FOR LOWS IN THE LOWER 60S DEG F.

TOMORROW:

THE LEE SURFACE TROUGH WILL STRENGTHEN TOMORROW AS MID TO UPPER LEVEL
FLOW BECOMES A BIT MORE PERPENDICULAR TO THE ROCKIES. I HAVE POPS INCREASING
UP TO THE SLIGHT CATEGORY TOWARDS 00Z TOMORROW EVENING AS WEAK 850 HPA
THETA-E ADVECTION STRENGTHENS AND SOME STORMS COULD FORM NEAR THE LEE
SURFACE TROUGH ACROSS THE W/NW ZONES. OTHERWISE, TOMORROW WILL BE MAINLY
DRY WITH HIGHS IN THE UPPER 80S TO AROUND 90 DEG F. THESE VALUES ARE
VERY CLOSE TO CLIMATOLOGY FOR THIS TIME OF YEAR. TOMORROW WILL BE A
BIT BREEZY.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 204 PM CDT TUE AUG 21 2012

THIS WEEK IS SHAPING UP INTO A RELATIVELY WET PATTERN. THE UPPER
LEVEL FLOW IS EVOLVING INTO A MORE PROGRESSIVE PATTERN WITH SHORT
AND LONG WAVES TRAVELING THROUGH THE UPPER PLAINS AND MIDWEST AT A
FAIRLY REGULAR INTERVAL. WE WILL BE ON THE SOUTH END OF MINOR
WAVES, WHICH WILL OVERFLOW AFTERNOON LEE SIDE SURFACE TROUGHS DURING
THE LATE AFTERNOON AND OVERNIGHT PERIODS. THEREFORE, PRECIPITATION
CHANCES WILL BE IN THE RANGE OF 30 PERCENT WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT AS A WEAK LOBE OF VORTICITY SCRAPES WEST TO EAST
THROUGH WESTERN KANSAS. THEN ON EARLY FRIDAY, A STRONGER WAVE UP
NORTH MOVING THROUGH THE DAKOTAS WILL SWING A MORE SIGNIFICANT WAVE
THROUGH KANSAS. DURING THE TIME FROM WEDNESDAY TO FRIDAY, DEW
POINTS WILL BE INCREASING INTO THE MID 60S TO LOWER 70S, ALLOWING
THE POTENTIAL FOR SOME HEAVY RAIN IN OUR SOUTHEAST COUNTIES FRIDAY
NIGHT AND SATURDAY AS THE LOWER LAYER BECOMES MORE SATURATED. THAT
WAVE WILL NOT GO DIRECTLY THROUGH OUR FORECAST AREA, BUT WILL DRAG
SLOWLY THROUGH WESTERN KANSAS ON A NORTHWEST TO SOUTHEAST
ORIENTATION. THIS WILL ALLOW A SURFACE FRONT TO STAY NEARLY
ANCHORED OVER OUR CENTRAL TO SOUTHEASTERN ZONES, AND SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO RE-FIRE ALONG AND SOUTHEAST OF THE
FRONTAL BOUNDARY. POPS WILL BUMP UP INTO THE 40 TO 50 PERCENT
RANGE, FOR SOME OF OUR EASTERN ZONES, WITH 60 PERCENT POPS FRIDAY
NIGHT AND AGAIN SATURDAY NIGHT ACROSS OUR SOUTHEASTERN ZONES,
SOUTHEAST OF A LINE FROM LARNED TO MEADE. DECIDED TO NOT GO AS HIGH
AS THE ECMWF MODEL IS FORECASTING THE QPF TO BE (ABOUT 4 INCHES
TOTAL QPF WED TO SUN) SOUTHEAST OF A PRATT TO ASHLAND LINE, BUT
NEARER THE 2 INCH RANGE, WHICH IS CLOSER TO THE GFS OUTPUT. THE
WAVE WILL BE NEARLY EXITING OUR EASTERN CWA BY SUNDAY, BUT SMALL 20
PERCENT POPS WILL LINGER SUNDAY MORNING ACROSS OUR EXTREME EASTERN
ZONES. AN UPPER LEVEL RIDGE WILL BUILD IN FROM THE SOUTH MONDAY,
AND SHOULD KEEP BOTH MONDAY AND TUESDAY DRY.

MAXIMUM TEMPERATURES WEDNESDAY AND THURSDAY WILL REACH THE NEAR 90F
RANGE, BUT THEN A COLD FRONT MOVING IN FRIDAY WILL BRING CLOUDS AND
PRECIPITATION TO HELP LOWER MAX T`S INTO THE MIDDLE TO UPPER 80S
SATURDAY. MAX TEMPS WILL BASICALLY STAY IN THE 80S SUNDAY AS WELL,
THEN BEGIN REBOUNDING UPWARD MONDAY AND TUESDAY INTO THE LOWER 90S.
WINDS DO NOT LOOK TO BE TOO STRONG THROUGH THE WED NT THROUGH TUE
PERIOD, BUT WILL MAINTAIN A SOUTHERLY FLOW SUNDAY INTO TUESDAY.
MINIMUM TEMPERATURES IN THE LOWER TO MIDDLE 60S THURSDAY WILL RISE
TO THE MIDDLE 60S NORTHWEST TO LOWER TO MID 70S SOUTHEAST FRIDAY,
SATURDAY, SUNDAY, MONDAY AND TUESDAY.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1200 PM CDT TUE AUG 21 2012

VFR CIGS EXPECTED THROUGH ENTIRE TAF PERIOD. SOUTHERLY WINDS WILL CONTINUE
AROUND 10 KT THROUGH TODAY AND INTO THE EVENING. WINDS WILL INCREASE
12 TO 20 KT TOMORROW IN ASSOCIATION WITH AN INTENSIFYING LEE SURFACE
TROUGH. CONVECTION IS POSSIBLE TOMORROW NIGHT BUT THIS IS OUTSIDE THE
TAF PERIOD.

.PRELIMINARY POINT TEMPS/POPS...
DDC 61 89 65 91 / 10 10 30 30
GCK 61 91 64 92 / 10 10 30 30
EHA 61 89 63 91 / 10 10 20 30
LBL 60 90 64 91 / 10 10 30 30
HYS 60 91 65 92 / 10 10 30 30
P28 61 91 66 90 / 10 10 30 30

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM...BURKE
AVIATION...SUGDEN

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

100 PM CDT TUE AUG 21 2012

...UPDATE TO SHORT TERM DISCUSSION...

.SYNOPSIS...
ISSUED AT 900 AM CDT TUE AUG 21 2012

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 100 PM CDT TUE AUG 21 2012

TONIGHT:

TOMORROW:

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 358 AM CDT TUE AUG 21 2012

IT HAS BEEN QUITE A WHILE SINCE WE HAVE SEEN AN UPPER-LEVEL PATTERN
LIKE THE ONE EVOLVING THIS WEEK. IS IT POSSIBLE THAT RICH GULF
MOISTURE WILL ACTUALLY MAKE IT BACK INTO WESTERN KANSAS WITHOUT
MIXING OUT? AND IS IT POSSIBLE THAT AN UPPER-LEVEL TROUGH WILL
ACTUALLY APPROACH KANSAS FROM THE WEST, AND ACTUALLY TAP SOME OF
THIS MOISTURE TO PRODUCE A FEW ROUNDS OF SHOWERS AND
THUNDERSTORMS? IT CERTAINLY SEEMS THAT WAY IF THE 00Z GFS AND
ECMWF COME ANYWHERE CLOSE TO VERIFYING. HOWEVER, BEFORE GETTING
TOO EXCITED ABOUT RAIN PROSPECTS, IT IS VERY UNCLEAR EXACTLY WHERE
IN THE PLAINS WILL HAVE THE BEST CHANCE FOR HEAVIER RAINFALL.

THE SYSTEM I AM REFERRING TO ABOVE WAS PART OF A LARGER UPPER-LEVEL
TROUGH THAT WAS SITUATED OFF OF THE WEST COAST AT 125W LONGITUDE
EARLY THIS MORNING. THIS SYSTEM IS PROGGED BY THE ECMWF AND GFS TO
SLOWLY PROGRESS INLAND INTO THE WESTERN UNITED STATES BY WEDNESDAY
AFTERNOON, NORTHERN ARIZONA BY THURSDAY NIGHT AND THEN INTO COLORADO
AND NEW MEXICO BY FRIDAY AFTERNOON. THE SPEED OF THIS SYSTEM
IS PROBLEMATIC GIVEN THE UNCERTAIN INTERACTION WITH A STRONGER JET
STREAM FURTHER NORTH. AHEAD OF THE UPPER-LEVEL LOW, A WEAK UPPER-LEVEL
SYSTEM THAT IS NOT DISCERNIBLE IN THE UPPER AIR DATA YET IS
ADVERTISED TO MOVE ACROSS THE CENTRAL PLAINS IN ZONAL FLOW FOR
WEDNESDAY AND THURSDAY. MEANWHILE, RICH LOW LEVEL MOISTURE THAT IS
CURRENTLY POSITIONED OVER THE SOUTHERN PLAINS IS ADVERTISED TO
MOVE NORTHWARD INTO KANSAS AS SOON AS WEDNESDAY EVENING. BY
WEDNESDAY EVENING, THIS WEAK SYSTEM IS PROGGED TO APPROACH THE
HIGH PLAINS. WITH DEWPOINTS CLIMBING INTO THE UPPER 50S ACROSS FAR
WESTERN KANSAS BY THIS TIME, ALONG WITH TEMPERATURES CLIMBING INTO
THE LOWER 90S, THERE MAY BE SUFFICIENT SURFACE BASED CAPE NEAR THE
LEE TROUGH IN EASTERN COLORADO FOR THUNDERSTORM INITIATION. ANY
STORMS THAT DO DEVELOP COULD GROW INTO A CLUSTER OF STORMS AND
PROGRESS ACROSS THE CENTRAL PLAINS WEDNESDAY NIGHT. BUT WHERE WILL
SUCH A CLUSTER BE LOCATED? IT IS SIMPLY TOO EARLY TO TELL. GIVEN
THE UNCERTAINTY, WE OPTED TO RETAIN THE 20-30% CHANCES FOR STORMS
DURING THIS PERIOD. THIS SYSTEM WILL STILL BE LOCATED OVER CENTRAL
KANSAS BY THURSDAY, SO IT IS POSSIBLE THAT THERE WILL BE LINGERING
AREAS OF SHOWERS AND THUNDERSTORMS SOMEWHERE ACROSS CENTRAL OR
EASTERN KANSAS ON THURSDAY. HENCE THE 20-30% CHANCES FOR
THUNDERSTORMS LOOK APPROPRIATE. TEMPERATURES FOR WEDNESDAY AND
THURSDAY WILL BE FAIRLY CLOSE TO CLIMATOLOGICAL AVERAGES, WITH
HIGHS IN THE UPPER 80S TO LOWER 90S AND LOWS MAINLY IN THE LOWER
TO MIDDLE 60S.

BY THURSDAY NIGHT AND FRIDAY, THE AFOREMENTIONED UPPER-LEVEL SYSTEM
OFF THE WEST COAST WILL BE GETTING CLOSER TO THE HIGH PLAINS REGION.
AND ALSO BY THIS TIME, THE MODELS, AND NOT JUST THE GFS, ARE SHOWING
EVEN HIGHER SURFACE DEWPOINTS WELL INTO THE 60S ACROSS SOUTHWEST AND
CENTRAL KANSAS. THIS SEEMS REASONABLE GIVEN THAT THE SOUTHERN EDGE
OF THE WESTERLIES WILL BE AS FAR SOUTH AS WE HAVE SEEN SINCE SPRING,
CAUSING A SOUTHWARD EXTENSION OF THE LEE TROUGH INTO SOUTHWEST
TEXAS AND NORTHERN MEXICO, AND A RESULTANT SURGE OF LOW LEVEL
MOISTURE FROM THE GULF OF MEXICO INTO KANSAS. IF THIS HAPPENS, THEN
SOME LOCATIONS ACROSS THE SOUTHERN OR CENTRAL PLAINS COULD EXPERIENCE
SOME MUCH NEEDED HEAVY RAINFALL. IT IS FAR TOO EARLY TO GET TOO
EXCITED ABOUT FURTHER DROUGHT RELIEF THIS FAR NORTHWEST IN THE
PLAINS, BUT THERE WILL BE CHANCES FOR THUNDERSTORMS EVERY DAY
THROUGH SATURDAY. HIGH TEMPERATURES DURING THIS PERIOD WILL DEPEND ON
HOW MUCH CLOUD COVER AND PRECIPITATION OCCUR. BUT IT DOESN`T LOOK
TOO HOT OR ALL THAT COOL EITHER, JUST BASICALLY WHAT ONE WOULD
EXPECT FOR THIS TIME OF YEAR, WITH HIGHS MAINLY IN THE 80S TO
PERHAPS AS HIGH AS 90. LOWS WILL BE HELD UP BY THE HIGHER DEWPOINTS
AND SHOULD BE MAINLY IN THE 60S.

A CLEARING TREND SHOULD COMMENCE BY SUNDAY PROVIDED THAT THE UPPER
LEVEL SYSTEM IS EAST OF OUR AREA BY THIS TIME AS ADVERTISED BY ALL
OF THE MODELS. HOWEVER, NEAR SEASONABLE TEMPERATURES CAN BE
EXPECTED TO PERSIST GIVEN THAT UPPER-LEVEL TROUGHING MAY STILL BE
NOT TOO FAR TO OUR EAST BY THIS TIME, WITH AN ABSENCE OF STRONG
LOW-LEVEL WARM ADVECTION. HOWEVER, BY EARLY TO MID NEXT WEEK, WARMER
TEMPERATURES WILL BE RETURNING TO THE PLAINS AS UPPER-LEVEL TROUGHING
DEVELOPS ACROSS THE NORTHWESTERN UNITED STATES. HIGH TEMPERATURES SHOULD
REBOUND INTO THE LOWER TO MIDDLE 90S BY TUESDAY AND POSSIBLY EVEN THE
UPPER 90S BY WEDNESDAY.

AFTER WEDNESDAY, LARGE DIFFERENCES START TO APPEAR IN THE MODELS,
ESPECIALLY IN REGARDS TO THE STRENGTH OF UPPER-LEVEL RIDGING ACROSS
THE PLAINS. THE 00Z GFS LOOKS SIMILAR TO THE 12Z ECMWF, WITH STRONGER
RIDGING OVER THE SOUTHERN AND EVEN CENTRAL PLAINS. THE 00Z ECMWF ADVERTISES
A WEAKER RIDGE BUT THIS MAY BE AN ABERRANT MODEL RUN SINCE THE GEM
SHOWS MORE RIDGING LIKE THE GFS. SO FAIRLY HOT WEATHER MAY PERSIST WITH
HIGHS IN THE 90S.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1200 PM CDT TUE AUG 21 2012

.PRELIMINARY POINT TEMPS/POPS...
DDC 85 61 89 65 / 10 10 10 30
GCK 86 61 91 64 / 10 10 10 30
EHA 82 61 89 63 / 10 10 10 20
LBL 85 60 90 64 / 10 10 10 30
HYS 90 60 91 65 / 10 10 10 30
P28 87 61 91 66 / 10 10 10 30

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM...FINCH
AVIATION...SUGDEN

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

1229 AM CDT TUE AUG 21 2012

...UPDATED SYNOPSIS AND AVIATION DISCUSSION...

.SYNOPSIS...
ISSUED AT 1215 AM CDT TUE AUG 21 2012

AT 00Z TUESDAY A 250MB JET STREAK EXTENDED FROM WYOMING TO
NORTHERN CALIFORNIA. THIS JET STREAK WAS ROTATING AROUND A 500MB
RIDGE AXIS THAT WAS LOCATED FROM UTAH TO IDAHO. ANOTHER UPPER
LEVEL JET STREAK APPEARS TO BE LOCATED EAST OF THIS UPPER LEVEL
RIDGE AXIS ACROSS EASTERN COLORADO. 500MB MOISTURE THIS MORNING STRETCHED
FROM THE UPPER LEVEL RIDGE AXIS EASTWARD INTO THE WESTERN HIGH
PLAINS. THE BETTER 700MB MOISTURE APPEARS TO BE LOCATED FROM DODGE
CITY TO AMARILLO TO NEAR ALBUQUERQUE. 05Z SATELLITE LOOP EVEN
INDICATED SOME CLEARING SKIES DEVELOPING ACROSS PARTS OF NORTHEAST
COLORADO AND NORTHWEST KANSAS. A WEDGE OF HIGHER DEWPOINTS AT THE
850MB LEVEL EXTENDED FROM SOUTHEAST COLORADO INTO THE PANHANDLE
OF TEXAS WHICH WAS ALSO WHERE THE 850MB BAROCLINIC ZONE WAS
LOCATED AND WHERE SOME WIND CONFLUENCE WAS EVIDENT EARLY THIS
MORNING.

.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 222 PM CDT MON AUG 20 2012

TONIGHT:

THE IMMEDIATE SHORT TERM FORECAST IS WHAT TO DO WITH POPS THIS EVENING.
NORTHWEST FLOW ALOFT AND OROGRAPHICALLY INDUCED CONVECTION ACROSS COLORADO WILL
CREATE A CLASSIC MCS LATE SUMMER TIME EVENT FOR FAR SW KANSAS. RIGHT
NOW THE MESOSCALE MODELS (NAM, WRF) SHOWS THAT THE BEST 310K ISENTROPIC
LIFT AND WARM AIR (THETA-E) ADVECTION WILL BE LOCATED ACROSS THE SOUTHWESTERN
COUNTIES. THIS AREA IS ALSO CLOSER TO AN APPROACHING 80 KT 250 HPA JET
STREAK MOVING ACROSS THE REGION TONIGHT. THE MOST RECENT HRRR IS QUITE
AGGRESSIVE WITH COMPOSITE REFLECTIVITIES AND ASSOCIATED PRECIPITATION
TOWARDS 05Z (MIDNIGHT) FOR THE CENTRAL COUNTIES. FOR NOW, WILL HOLD
OFF ON THIS SOLUTION SINCE THIS MODEL MIGHT BE OVERDOING THE RESULTANT
COLD POOL FROM THE CONVECTIVE SCHEME. HAVE DOUBTS FOR SEVERE WEATHER
AS DEWPOINTS ARE MAINLY IN THE 40S DEG F. THERE ARE SOME HIGHER DEWPOINTS
(LOWER 50S DEG F) ACROSS THE PANHANDLES, BUT THIS BETTER MOISTURE SHOULD
STAY SOUTH OF THE REGION. KINEMATIC PROFILES SUGGEST THE POSSIBILITY
OF SEVERE WEATHER WITH 0-6 KM BULK SHEAR FORECAST TO BE ABOUT 45 KT
AND ANVIL LEVEL STORM RELATIVE WINDS AROUND 80 KT. THE FLY IN THE OINTMENT
FOR THIS EVENING IS MEAGER CAPE ASSOCIATED WITH MARGINAL BOUNDARY
LAYER DEWPOINTS. 700-500 HPA LAPSE RATES AROUND 7.5 C/KM AND 500-300
HPA LAPSE RATES AROUND 6.7 C/KM IN COMBINATION WITH 500 J/KG OF
SBCAPE SUGGEST MARGINAL HAIL FOR ANY SUSTAINED UPDRAFT - MAINLY
TOWARDS ELKHART.

TOMORROW:

KEPT THE IDEA OF LOWER TEMPERATURES ACROSS THE SW COUNTIES AS TEMPERATURES
SHOULD BE MODERATED BY THE ANTICIPATED RAINFALL ACROSS THE REGION. I
HAVE LOWER 80S DEG F FOR THE SOUTHWEST COUNTIES AND MID TO UPPER 80S
DEG F ELSEWHERE. THINK THE 12Z NAM IS OVERDOING TEMPS ACROSS THIS REGION.
MAX CLIMO FOR THE REGION IS AROUND 88 DEG F FOR TOMORROW. THE 12Z NAM
IS SUGGESTING THE POSSIBILITY FOR CONVECTION ACROSS FAR WESTERN KANSAS
ALONG THE LEE SURFACE TROUGH FOR TOMORROW EVENING. WILL PUT SLIGHT POPS
IN THE GRIDS FOR NOW. NOT TOTALLY CONFIDENT AS UPPER LEVEL DYNAMICS
ARE FORECAST TO BE ON THE WEAKER SIDE TOMORROW.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 246 PM CDT MON AUG 20 2012

FOR TUESDAY NIGHT INTO WEDNESDAY MORNING, WILL PHASE OUT 20 PERCENT
SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS FROM OUR WESTERN
FORECAST POINTS NEAR SYRACUSE AND ELKHART BY 06Z. THE TROUGH THE
AFTERNOON CONVECTION WILL TRIGGER ON LATE TUESDAY WILL SLOWLY
DISSIPATED DURING THE EARLY OVERNIGHT PERIOD TUESDAY NIGHT.
ANOTHER SHORT WAVE WILL COME THROUGH THE NORTHWEST FLOW ALOFT LATE
WEDNESDAY AND GENERATE ANOTHER LOW PRESSURE TROUGH NEAR OUR WESTERN
BORDER. LOW 20 POPS FOR ELEVATED THUNDERSTORMS WILL RESULT AFTER
21Z WEDNESDAY, AND SPREAD EASTWARD DURING THE EVENING WEDNESDAY.
THE SURROUND OFFICES SEEMED TO FAVOR 30 PERCENT CHANCE POPS WED, SO
I STUCK WITH 30 POPS FOR ALL AREAS EXCEPT 40 PERCENT POPS IN IN OUR
EASTERN 2 TIERS OF COUNTIES, EAST OF A LINE FROM LARNED TO COLDWATER
WED NIGHT. MOST OF THESE THUNDERSTORMS WILL LIKELY BE ELEVATED AND
ONLY PRODUCE RAINFALL IN THE 0.10 RANGE IN OUR SOUTHEAST ZONES, BUT
SOMEWHAT LOWER AND ONLY IN THE 0.02 TO 0.06-INCH RANGE UP NORTH AND
TO THE WEST. THOSE UPPER WAVES ARE JUST STACKED ONE AFTER ANOTHER,
SO PRECIP CHANCES IN THE 20 TO 30 PERCENT RANGE WILL CONTINUE INTO
THURSDAY, BUT INCREASE IN THE 40 PERCENT RANGE ACROSS OUR EASTERN
1/3RD OF THE CWA, BASICALLY EAST OF A WAKEENEY TO KINSLEY TO MEADE
LINE. A STEADY SOUTHERLY FLOW WILL BRING MID 60S DEW POINTS INTO
THAT AREA THURSDAY AFTERNOON, AND A SYNOPTIC SCALE UPPER WAVE WILL
CROSS JUST NORTH OF OUR CWA THURSDAY NIGHT.

FRIDAY SHOULD SEE A LITTLE RELAXING/WEAKENING OF THE STRENGTH OF
THE PASSING UPPER WAVE, WITH ONLY OUR SOUTHEAST ZONES NEAR MEDICINE
LODGE CARRYING 30 POPS. AS A WARM FRONT NUDGES NORTH FRIDAY NIGHT
AND STEADY UPPER SCALE LIFT STAYS OVER WESTERN KANSAS, MUCH OF THE
CWA COULD SEE HIGH BASED SHOWERS AND ISOLATED STORMS FRIDAY NIGHT.
A CHANCE CATEGORY 30 PERCENT POPS WILL COVER MUCH OF THE EASTERN
HALF OF THE FORECAST AREA, WHILE 20 POPS WILL BE OVER THE SOUTHWEST
ZONES FRI NT. SATURDAY, SATURDAY NIGHT AND SUNDAY ALL LOOK GOOD FOR
30 TO 40 PERCENT RAIN CHANCES IN OUR EASTERN HALF OF THE CWA, WITH
EVEN OUR SOUTHWEST COUNTIES HAVING A 20 PERCENT CHANCE SATURDAY
NIGHT. SUNDAY WAS SOMEWHAT QUESTIONABLE AS TO WHERE THE UPPER WAVE
WILL BE, BUT OUR EASTERN-MOST ZONES FROM HAYS TO PRATT TO MEDICINE
LODGE WILL STILL HAVE 20 POPS. BY SUNDAY, THE LAST IN A SERIES OF
UPPER WAVES COULD BE FAR ENOUGH EAST TO LEAVE POPS OUT OF OUR EAST
ZONES ALL TOGETHER SUNDAY. WILL HAVE TO SEE THE NEXT MODEL RUN TO
DETERMINE IF PRECIP CHANCES ARE WARRANTED SUNDAY.

AS FOR TEMPERATURES, I ACCEPTED WHAT THE CREXTENDFCST_INIT PROCEDURE
GAVE ME. BASICALLY, FOR WEDNESDAY THROUGH SUNDAY, HIGH TEMPERATURES
WILL BE IN THE MID TO UPPER 80S ACROSS OUR NORTHERN HALF OF THE CWA,
AND FROM THE UPPER 80S TO LOWER 90S IN OUR SOUTHERN HALF. MINIMUM
TEMPERATURES WILL START OUT IN THE LOWER 60S WEDNESDAY, AND WARM TO
THE MID 60S TO LOWER 70S (SE) FRIDAY THROUGH SUNDAY.

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1215 AM CDT TUE AUG 21 2012

MOISTURE IN THE 850-700MB LEVEL WILL BE PRESENT THROUGH AT LEAST
LATE MORNING AT DDC AND GCK AS WEAK WARM AIR ADVECTION DEVELOPS
ACROSS SOUTHWEST KANSAS. THIS SHOULD RESULT IN A PERIOD OF VFR
CIGS BETWEEN THE 7000 AND 10000 FEET EARLY TODAY. SOUTHERLY WINDS ARE
EXPECTED TO CONTINUE AND WILL INCREASE INTO THE 10 TO 15 KNOT
RANGE BY LATE DAY AS SURFACE PRESSURES BEGIN TO FALL ALONG THE LEE
OF THE ROCKIES.

.PRELIMINARY POINT TEMPS/POPS...
DDC 61 86 64 86 / 10 20 30 20
GCK 61 88 64 88 / 20 20 30 20
EHA 62 88 65 87 / 20 20 20 20
LBL 62 88 66 87 / 20 20 30 20
HYS 61 90 65 87 / 10 20 30 30
P28 62 89 66 86 / 10 20 40 20

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SYNOPSIS...BURGERT
SHORT TERM...SUGDEN
LONG TERM...BURKE
AVIATION...BURGERT

AREA FORECAST DISCUSSION

NWS CARIBOU ME

1139 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A WEAK COLD FRONTAL WILL CROSS THE STATE TODAY INTO TONIGHT WITH
SOME SHOWERS POSSIBLE. ANOTHER WEAK DISTURBANCE WILL MOVE ACROSS THE
REGION ON WEDNESDAY.
&&

.NEAR TERM /THROUGH TONIGHT/...
11:40 AM UPDATE...SHOWERS ARE TAPERING OFF. ONLY A FEW VERY LIGHT
SPOTTY SHOWERS REMAIN IN EASTERN AREAS AND THESE WILL DISSIPATE
EARLY THIS AFTERNOON. THE SKY WILL TURN OUT SUNNY TO PARTLY CLOUDY
WITH A DRY AFTERNOON. LOWERED TEMPS JUST A COUPLE DEGREES SINCE
CLOUD COVER THIS MORNING SLOWED THE INCREASE IN TEMPS A BIT.

PREVIOUS DISCUSSION...
MAIN CHALLENGE THIS TERM WILL BE SHOWER ACTIVITY AND QPF.

LATEST RADAR SHOWED ACTIVITY MOVING INTO WNW MAINE THIS MORNING
W/ECHOES UP TO 30DBZ WHICH LEADS TO THE POTENTIAL FOR SOME SHOWER
ACTIVITY TO REACH THE GROUND. SATL IMAGERY & CEILING PLOTS
INDICATED CLOUD DECKS OF 7K-10K FT. THIS IS REFLECTED IN THE UPPER
AIR ANALYSIS. THE LATEST NAM AND GFS HAVE INITIALIZED WELL W/THE
LATEST RADAR IMAGERY. HRRR INITIALIZED WELL BUT SEEMS TO BE
OVERDONE W/ITS RAINFALL OVERSPREADING THE CWA BY LATE MORNING INTO
THE AFTERNOON. MID LEVEL FORCING ALONG W/LLVL CONVERGENCE ALONG
AND JUST AHEAD OF THE FRONTAL BOUNDARY WILL ALLOW FOR SHOWERS
TODAY. ATTM, USED A BLEND OF THE NAM12 AND GFS FOR THE POPS WHICH
SHOW 20-40% ACROSS THE CWA EXCEPT THE COAST. HPC QPF LOOKS
OVERDONE AND TOO FAR SOUTH. THEREFORE, DECIDED TO BLEND THE
NAM12/HPC AND SREF FOR QPF WHICH SHOWS NO MORE THAN .10 OF AN INCH
AND THIS WILL BE MAINLY ACROSS THE CENTRAL AND EASTERN AREAS.
STAYED CLOSE W/THE DAYCREW`S MAXES FOR TODAY W/MID 70S NORTH AND
UPPER 70S TO AROUND 80 FOR THE CENTRAL AND DOWNEAST AREAS. ANOTHER
FACTOR TODAY WILL BE WINDS AND MDL SOUNDINGS INDICATE AN INVERTED
V-SOUNDING WHICH SUPPORTS SOME WIND TO POSSIBLY MIX DOWN. DECIDED
TO BOOST WIND GUSTS TO 20 MPH MAINLY ACROSS THE HIGHER TERRAIN AND
OPEN AREAS.

TONIGHT WILL SEE CLOUDS BEGINNING TO BREAK UP AS THE FRONT SLOWLY
SLIDES TO THE EAST. SOME CAA IS SEEN BEHIND THE FRONT AND W/WINDS
BECOMING LIGHT AND A WET GROUND, THINKING HERE IS THAT SOME FOG
WILL FORM. BUFKIT PROFILES SUPPORT THIS THINKING. MID LEVEL MOISTURE
IS SHOWN BY THE GFS AND NAM TO MOVE ACROSS NORTHERN AREAS OVERNIGHT.
THIS COULD HALT FURTHER PROGRESSION OF THE FOG. ADDED FOG TO THE
FORECAST BUT NOT CONFIDENT TO GO ANY MORE THAN USING PATCHY
WORDING. DAYCREW CAN ASSESS THIS FURTHER. TEMPERATURES WILL BE
COOL W/MINS DROPPING BACK INTO THE MID AND UPPER 40S ACROSS THE
NORTH AND WEST AND LOW TO MID 50S FOR THE CENTRAL AND DOWNEAST
REGIONS.

.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL REMAIN TO OUR SOUTH ON WEDNESDAY AS LOW
PRESSURE MOVES EAST ACROSS ONTARIO/QUEBEC PROVINCE. THIS WILL KEEP
A SOUTHWEST FLOW AND WEAK WARM ADVECTION ACROSS THE REGION ON
WEDNESDAY WITH PARTLY/MOSTLY SUNNY SKIES. HIGHS ON WEDNESDAY WILL
RANGE FROM THE LOW/MID 70S NORTH AND UPPER 70S TO NEAR 80
DOWNEAST. A DRY NIGHT CAN BE EXPECTED WEDNESDAY NIGHT AS LOW
PRESSURE CONTINUES TO SLIDE TO OUR NORTH. LOWS WEDNESDAY NIGHT
WILL RANGE FROM THE LOW TO MID 50S. A COLD FRONT WILL SLIDE ACROSS
THE REGION ON THURSDAY. SB CAPES ARE UNIMPRESSIVE SO WILL NOT
INCLUDE THE MENTION OF THUNDER BUT WILL MENTION THE CHANCE FOR
AFTERNOON SHOWERS MAINLY ACROSS NORTHERN AND CENTRAL AREAS. HIGH
ON THURSDAY WILL RANGE FROM THE MID TO UPPER 70S NORTH AND LOW TO
MID 80S DOWNEAST...BUT IT WILL BE COOLER NEAR THE COAST.

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR THURSDAY NIGHT AND
FRIDAY. THIS WILL BRING MAINLY CLEAR SKIES TO THE REGION THURSDAY
NIGHT AND MOSTLY SUNNY SKIES ON FRIDAY. HIGH PRESSURE WILL SLIDE
EAST ON SATURDAY AND SUNDAY WITH CONTINUED DRY WEATHER. A FRONT WILL
APPROACH FROM THE WEST SUNDAY NIGHT WITH INCREASING CLOUDS. THE
FRONT WILL SLIDE EAST ACROSS THE REGION MONDAY WITH THE CHANCE FRO
SHOWERS.

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: STAYED CLOSE TO VFR INTO TONIGHT. SOME PATCHY FOG
COULD ALLOW FOR BRIEF MVFR/IFR CONDITIONS AT THE AIRFIELDS EARLY
WEDNESDAY MORNING. FOG SHOULD LIFT AND BURN OFF BY 8 AM.

SHORT TERM: MAINLY VFR THROUGH THE PERIOD.

.MARINE...
NEAR TERM: NO HEADLINES. SSE SWELL WILL CONTINUE THROUGH THE
PERIOD W/WAVE HEIGHTS OF 2-3 FT AND THIS WILL MAINLY BE AWAY FROM
THE INTRA-COASTAL WATERS. WINDS WILL LIGHT AVERAGING 5-10 KTS.

SHORT TERM: WIND/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE
PERIOD.

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.

$$
NEAR TERM...HEWITT/MCB
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT
MARINE...HEWITT/DUDA

AREA FORECAST DISCUSSION

NWS CARIBOU ME

1011 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A WEAK COLD FRONTAL WILL CROSS THE STATE TODAY INTO TONIGHT WITH
SOME SHOWERS POSSIBLE. ANOTHER WEAK DISTURBANCE WILL MOVE ACROSS THE
REGION ON WEDNESDAY.
&&

.NEAR TERM /THROUGH TONIGHT/...
10:00 AM UPDATE...SHOWERS CONTINUE MOVING EAST AND SATELLITE
IMAGERY SHOWS CLEARING FOLLOWING THIS LINE OF SHOWERS SO UPDATED
FORECAST TO GO PARTLY TO MOSTLY SUNNY THIS AFTERNOON FOLLOWING
THE PASSAGE OF THE FRONT.

PREVIOUS DISCUSSION...
MAIN CHALLENGE THIS TERM WILL BE SHOWER ACTIVITY AND QPF.

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: STAYED CLOSE TO VFR INTO TONIGHT. SOME PATCHY FOG
COULD ALLOW FOR BRIEF MVFR/IFR CONDITIONS AT THE AIRFIELDS EARLY
WEDNESDAY MORNING. FOG SHOULD LIFT AND BURN OFF BY 8 AM.

SHORT TERM: MAINLY VFR THROUGH THE PERIOD.

SHORT TERM: WIND/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE
PERIOD.

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.

$$
NEAR TERM...HEWITT/MCB
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT
MARINE...HEWITT/DUDA

AREA FORECAST DISCUSSION

NWS CARIBOU ME

826 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A WEAK COLD FRONTAL WILL CROSS THE STATE TODAY INTO TONIGHT WITH
SOME SHOWERS POSSIBLE. ANOTHER WEAK DISTURBANCE WILL MOVE ACROSS THE
REGION ON WEDNESDAY.
&&

.NEAR TERM /THROUGH TONIGHT/...
8:30 AM UPDATE...SOLID BAND OF SHOWERS IS MOVING EAST. AS OF 8:30
AM IT WAS ON A LINE FROM EASTERN AROOSTOOK COUNTY SOUTHWEST
ACROSS PENOBSCOT AND PISCATAQUIS COUNTIES. UPDATED TO FORECAST
NUMEROUS SHOWERS IN THIS BAND THIS MORNING. SHOWERS ARE LIGHT AND
SHOULD GIVE A TENTH OF AN INCH OR LESS OF RAINFALL AS IT MOVES
ACROSS. THE LINE OF SHOWERS SHOULD CLEAR THE AREA BY EARLY THIS
AFTERNOON.

PREVIOUS DISCUSSION...
MAIN CHALLENGE THIS TERM WILL BE SHOWER ACTIVITY AND QPF.

LATEST RADAR SHOWED ACTIVITY MOVING INTO WNW MAINE THIS MORNING W/ECHOES
UP TO 30DBZ WHICH LEADS TO THE POTENTIAL FOR SOME SHOWER ACTIVITY
TO REACH THE GROUND. SATL IMAGERY & CEILING PLOTS INDICATED CLOUD
DECKS OF 7K-10K FT. THIS IS REFLECTED IN THE UPPER AIR ANALYSIS.
THE LATEST NAM AND GFS HAVE INITIALIZED WELL W/THE LATEST RADAR
IMAGERY. HRRR INITIALIZED WELL BUT SEEMS TO BE OVERDONE W/ITS
RAINFALL OVERSPREADING THE CWA BY LATE MORNING INTO THE AFTERNOON.
MID LEVEL FORCING ALONG W/LLVL CONVERGENCE ALONG AND JUST AHEAD OF
THE FRONTAL BOUNDARY WILL ALLOW FOR SHOWERS TODAY. ATTM, USED A
BLEND OF THE NAM12 AND GFS FOR THE POPS WHICH SHOW 20-40% ACROSS
THE CWA EXCEPT THE COAST. HPC QPF LOOKS OVERDONE AND TOO FAR
SOUTH. THEREFORE, DECIDED TO BLEND THE NAM12/HPC AND SREF FOR QPF
WHICH SHOWS NO MORE THAN .10 OF AN INCH AND THIS WILL BE MAINLY
ACROSS THE CENTRAL AND EASTERN AREAS. STAYED CLOSE W/THE DAYCREW`S
MAXES FOR TODAY W/MID 70S NORTH AND UPPER 70S TO AROUND 80 FOR THE
CENTRAL AND DOWNEAST AREAS. ANOTHER FACTOR TODAY WILL BE WINDS AND
MDL SOUNDINGS INDICATE AN INVERTED V-SOUNDING WHICH SUPPORTS SOME
WIND TO POSSIBLY MIX DOWN. DECIDED TO BOOST WIND GUSTS TO 20 MPH
MAINLY ACROSS THE HIGHER TERRAIN AND OPEN AREAS.

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR THURSDAY NIGHT AND
FRIDAY. THIS WILL BRING MAINLY CLEAR SKIES TO THE REGION THURSDAY
NIGHT AND MOSTLY SUNNY SKIES ON FRIDAY. HIGH PRESSURE WILL SLIDE
EAST ON SATURDAY AND SUNDAY WITH CONTINUED DRY WEATHER. A FRONT WILL
APPROACH FROM THE WEST SUNDAY NIGHT WITH INCREASING CLOUDS. THE FRONT
WILL SLIDE EAST ACROSS THE REGION MONDAY WITH THE CHANCE FRO
SHOWERS.

.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: STAYED CLOSE TO VFR INTO TONIGHT. SOME PATCHY FOG COULD
ALLOW FOR BRIEF MVFR/IFR CONDITIONS AT THE AIRFIELDS EARLY
WEDNESDAY MORNING. FOG SHOULD LIFT AND BURN OFF BY 8 AM.

SHORT TERM: MAINLY VFR THROUGH THE PERIOD.

SHORT TERM: WIND/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE PERIOD.

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.

$$
NEAR TERM...HEWITT/MCB
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT
MARINE...HEWITT/DUDA

AREA FORECAST DISCUSSION

NWS CARIBOU ME

656 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A WEAK COLD FRONTAL WILL CROSS THE STATE TODAY INTO TONIGHT WITH
SOME SHOWERS POSSIBLE. ANOTHER WEAK DISTURBANCE WILL MOVE ACROSS THE
REGION ON WEDNESDAY.

.NEAR TERM /THROUGH TONIGHT/...
UPDATE...ADJUSTED THE SKY AND TEMPERATURES TO MATCH THE INITIAL
CONDITIONS. SATL IMAGERY SHOWING CLOUDS STREAMING NE ACROSS THE
STATE. RADAR HAD A LINE OF HEAVIER ECHOES(30DBZ) MOVING E. DID AN
AREAL ADJUSTMENT ON THE POPS TO ACCOUNT FOR WHAT THE RADAR WAS
INDICATING.

PREVIOUS DISCUSSION...
MAIN CHALLENGE THIS TERM WILL BE SHOWER ACTIVITY AND QPF.

LATEST RADAR SHOWED ACTIVITY MOVING INTO WNW MAINE THIS MORNING W/ECHOES
UP TO 30DBZ WHICH LEADS TO THE POTENTIAL FOR SOME SHOWER ACTIVITY
TO REACH THE GROUND. SATL IMAGERY & CEILING PLOTS INDICATED CLOUD
DECKS OF 7K-10K FT. THIS IS REFLECTED IN THE UPPER AIR ANALYSIS.
THE LATEST NAM AND GFS HAVE INITIALIZED WELL W/THE LATEST RADAR
IMAGERY. HRRR INITIALIZED WELL BUT SEEMS TO BE OVERDONE W/ITS
RAINFALL OVERSPREADING THE CWA BY LATE MORNING INTO THE AFTERNOON.
MID LEVEL FORCING ALONG W/LLVL CONVERGENCE ALONG AND JUST AHEAD OF
THE FRONTAL BOUNDARY WILL ALLOW FOR SHOWERS TODAY. ATTM, USED A
BLEND OF THE NAM12 AND GFS FOR THE POPS WHICH SHOW 20-40% ACROSS
THE CWA EXCEPT THE COAST. HPC QPF LOOKS OVERDONE AND TOO FAR
SOUTH. THEREFORE, DECIDED TO BLEND THE NAM12/HPC AND SREF FOR QPF
WHICH SHOWS NO MORE THAN .10 OF AN INCH AND THIS WILL BE MAINLY
ACROSS THE CENTRAL AND EASTERN AREAS. STAYED CLOSE W/THE DAYCREW`S
MAXES FOR TODAY W/MID 70S NORTH AND UPPER 70S TO AROUND 80 FOR THE
CENTRAL AND DOWNEAST AREAS. ANOTHER FACTOR TODAY WILL BE WINDS AND
MDL SOUNDINGS INDICATE AN INVERTED V-SOUNDING WHICH SUPPORTS SOME
WIND TO POSSIBLY MIX DOWN. DECIDED TO BOOST WIND GUSTS TO 20 MPH
MAINLY ACROSS THE HIGHER TERRAIN AND OPEN AREAS.

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR THURSDAY NIGHT AND
FRIDAY. THIS WILL BRING MAINLY CLEAR SKIES TO THE REGION THURSDAY
NIGHT AND MOSTLY SUNNY SKIES ON FRIDAY. HIGH PRESSURE WILL SLIDE
EAST ON SATURDAY AND SUNDAY WITH CONTINUED DRY WEATHER. A FRONT WILL
APPROACH FROM THE WEST SUNDAY NIGHT WITH INCREASING CLOUDS. THE FRONT
WILL SLIDE EAST ACROSS THE REGION MONDAY WITH THE CHANCE FRO
SHOWERS.

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: STAYED CLOSE TO VFR INTO TONIGHT. SOME PATCHY FOG COULD
ALLOW FOR BRIEF MVFR/IFR CONDITIONS AT THE AIRFIELDS EARLY
WEDNESDAY MORNING. FOG SHOULD LIFT AND BURN OFF BY 8 AM.

SHORT TERM: MAINLY VFR THROUGH THE PERIOD.

SHORT TERM: WIND/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE PERIOD.

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.

$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT
MARINE...HEWITT/DUDA

AREA FORECAST DISCUSSION

NWS CARIBOU ME

431 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A WEAK COLD FRONTAL WILL CROSS THE STATE TODAY INTO TONIGHT WITH
SOME SHOWERS POSSIBLE. ANOTHER WEAK DISTURBANCE WILL MOVE ACROSS THE
REGION ON WEDNESDAY.

.NEAR TERM /THROUGH TONIGHT/...
MAIN CHALLENGE THIS TERM WILL BE SHOWER ACTIVITY AND QPF.

LATEST RADAR SHOWED ACTIVITY MOVING INTO WNW MAINE THIS MORNING W/ECHOES
UP TO 30DBZ WHICH LEADS TO THE POTENTIAL FOR SOME SHOWER ACTIVITY
TO REACH THE GROUND. SATL IMAGERY & CEILING PLOTS INDICATED CLOUD
DECKS OF 7K-10K FT. THIS IS REFLECTED IN THE UPPER AIR ANALYSIS.
THE LATEST NAM AND GFS HAVE INITIALIZED WELL W/THE LATEST RADAR
IMAGERY. HRRR INITIALIZED WELL BUT SEEMS TO BE OVERDONE W/ITS
RAINFALL OVERSPREADING THE CWA BY LATE MORNING INTO THE AFTERNOON.
MID LEVEL FORCING ALONG W/LLVL CONVERGENCE ALONG AND JUST AHEAD OF
THE FRONTAL BOUNDARY WILL ALLOW FOR SHOWERS TODAY. ATTM, USED A
BLEND OF THE NAM12 AND GFS FOR THE POPS WHICH SHOW 20-40% ACROSS
THE CWA EXCEPT THE COAST. HPC QPF LOOKS OVERDONE AND TOO FAR
SOUTH. THEREFORE, DECIDED TO BLEND THE NAM12/HPC AND SREF FOR QPF
WHICH SHOWS NO MORE THAN .10 OF AN INCH AND THIS WILL BE MAINLY
ACROSS THE CENTRAL AND EASTERN AREAS. STAYED CLOSE W/THE DAYCREW`S
MAXES FOR TODAY W/MID 70S NORTH AND UPPER 70S TO AROUND 80 FOR THE
CENTRAL AND DOWNEAST AREAS. ANOTHER FACTOR TODAY WILL BE WINDS AND
MDL SOUNDINGS INDICATE AN INVERTED V-SOUNDING WHICH SUPPORTS SOME
WIND TO POSSIBLY MIX DOWN. DECIDED TO BOOST WIND GUSTS TO 20 MPH
MAINLY ACROSS THE HIGHER TERRAIN AND OPEN AREAS.

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR THURSDAY NIGHT AND
FRIDAY. THIS WILL BRING MAINLY CLEAR SKIES TO THE REGION THURSDAY
NIGHT AND MOSTLY SUNNY SKIES ON FRIDAY. HIGH PRESSURE WILL SLIDE
EAST ON SATURDAY AND SUNDAY WITH CONTINUED DRY WEATHER. A FRONT WILL
APPROACH FROM THE WEST SUNDAY NIGHT WITH INCREASING CLOUDS. THE FRONT
WILL SLIDE EAST ACROSS THE REGION MONDAY WITH THE CHANCE FRO
SHOWERS.

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: STAYED CLOSE TO VFR INTO TONIGHT. SOME PATCHY FOG COULD
ALLOW FOR BRIEF MVFR/IFR CONDITIONS AT THE AIRFIELDS EARLY
WEDNESDAY MORNING. FOG SHOULD LIFT AND BURN OFF BY 8 AM.

SHORT TERM: MAINLY VFR THROUGH THE PERIOD.
&&

SHORT TERM: WIND/SEAS SHOULD REMAIN BELOW SCA LEVELS THROUGH THE PERIOD.
&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.

$$
NEAR TERM...HEWITT
SHORT TERM...DUDA
LONG TERM...DUDA
AVIATION...HEWITT
MARINE...HEWITT/DUDA

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

417 PM EDT TUE AUG 21 2012

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 412 PM EDT TUE AUG 21 2012

12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALF OVER
THE UPR GRT LKS BTWN UPR TROF OVER ERN CAN/NE CONUS THAT IS SLOWLY
LIFTING OUT AND AN UPR RDG IN THE ROCKIES/PLAINS. SFC HI PRES
CENTERED OVER SW WI/LGT WLY FLOW ON ITS NRN FLANK AS WELL AS VERY
DRY AIR SHOWN ON THE 12Z INL/MPX RAOBS ARE BRINGING A TRANQUIL DRY
DAY TO UPR MI. THE ONLY FLY IN THE OINTMENT IS SOME MAINLY HI CLDS
DRIFTING SEWD INTO MAINLY THE E HALF OF THE CWA. THESE CLDS ARE ON
THE SRN FLANK OF AREA OF THICKER CLDS/A FEW -SHRA OVER ONTARIO
ASSOCIATED WITH DEEPER MSTR DEPICTED ON THE 12Z YPL RAOB AND WAD IN
ADVANCE OF SHRTWV EMBEDDED IN NW FLOW ALF AND NOW MOVING INTO FAR NW
ONTARIO.

MAIN FCST CONCERNS THRU WED WL BE PCPN CHCS ASSOCIATED WITH SHRTWV
FCST TO DROP SEWD THRU ONTARIO.

TNGT...SHRTWV NOW MOVING INTO FAR NW ONTARIO AND ASSOCIATED SFC LO
IS PROGGED TO DRIFT SEWD TO JUST W OF JAMES BAY BY 12Z WED.
ATTENDANT SFC TROF IS FCST TO STRETCH FM SFC LO WSWD THRU NRN LK SUP
TO NEAR ISLE ROYALE. THE EXPECTED MOTION OF THE SHRTWV INDICATES
BEST DPVA/DEEPER DEEP LYR QVECTOR CNVGC WL REMAIN FOCUSED IN ONTARIO.
ANOTHER SIGNIFICANT DETRIMENT TO PCPN CHCS WL BE VERY DRY LLVL AIR
SHOWN ON THE 12Z MPX/INL RAOBS AS INCRSG LLVL WSW FLOW TO THE S OF
SFC-H85 TROF WL BE DRAWING THIS AIR TOWARD UPR MI. SO ALTHOUGH
MODELS SHOW AN EXPANDING AREA OF H7 MSTR RELATED TO ISENTROPIC
ASCENT ON THE 305K SFC...NAM FCST SDNGS INDICATE THIS MOISTER LYR WL
BE RATHER THIN AND CAP MUCH DRIER LLVLS. THE GFS SHOWS MORE LLVL
MSTR...BUT WL TEND TO FOLLOW THE NAM GUIDANCE CONSIDERING THE
DRYNESS OF THE LLVLS OBSVD UPSTREAM. FOR THESE REASONS...OPTED TO GO
DRY TNGT AND LIMIT SCHC POPS ONLY TO THE FAR NRN CWA NEAR INCOMING
SFC TROF. OTRW...INCRSG WSW FLOW WL TEND TO LIMIT THE DIURNAL TEMP
FALL...ESPECIALLY IN DOWNSLOPE AREAS NEAR LK SUP THAT WL ALSO SEE
MORE AC RELATED TO H7 MOISTENING OVERNGT.

WED...SHRTWV TO THE NE IS PROGGED TO SLIDE TO THE E...TAKING DEEP
LYR QVECTOR CNVGC/H7 MSTR WITH IT. IN THE ABSENCE OF SGNFT MID LVL
FORCING AND WITH LLVL DRY AIR LINGERING TO THE S OF SFC LO PRES
TROF...THINK PCPN CHCS ARE MINIMAL. ALTHOUGH THE 12Z GFS GENERATES
SOME SPOTTY LGT QPF OVER PORTIONS OF MAINLY THE NCNTRL AND E...
OPTED TO FOLLOW THE BULK OF OTHER GUIDANCE AND KEEP THE LAND CWA
DRY...WITH SCHC POPS RESTRICTED TO NE LK SUP...CLOSER TO MID LVL
FORCING/MSTR. WITH H85 TEMPS PROGGED TO PEAK FM ARND 15C OVER THE E
TO 17C OVER THE W...EXPECT A WARMER DAY. DEEP MIXING ON NAM FCST
SDNGS SUG HI TEMPS WL REACH THE MID 80S OVER THE INTERIOR. A
WEAKENING PRES GRADIENT IN THE AFTN WL ALLOW FOR LK BREEZES TO FORM
AND MODERATE TEMPS NEAR THE LKSHORES.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 412 PM EDT TUE AUG 21 2012

WEDNESDAY NIGHT...
WILL BEGIN WITH NW FLOW ALOFT AT 00Z THURSDAY /AND A WEAK SFC FRONT
NEARLY STATIONARY W TO E OVER THE CWA/...WITH A WEAK 500MB RIDGE SET
UP ALONG THE RED RIVER VALLEY OF THE N. EXPECT THIS RIDGE TO PUSH
ACROSS THE UPPER GREAT LAKES THURSDAY MORNING INTO THE EARLY
AFTERNOON HOURS...BEFORE GETTING PUSHED E /THANKS THE TO THE E
MOTION OF THE CURRENT TROUGH SET UP LONG THE PACIFIC COAST/. WEAK S
FLOW SHOULD HELP KEEP TEMPS ROUGHLY 5F WARMER THAN TONIGHT.

THURSDAY AFTERNOON THROUGH FRIDAY NIGHT...
LOOK FOR THE N EXTENT OF THE PACIFIC TROUGH TO PUSH ACROSS THE
DAKOTAS THURSDAY MORNING...AND ACROSS THE UPPER GREAT LAKES THURSDAY
AFTERNOON INTO THURSDAY NIGHT. FCST MODELS ARE PRETTY CONSISTENT IN
HAVING THE TROUGH DIRECTLY OVERHEAD AT 18Z FRIDAY...BEFORE SHIFTING
NE TO ONTARIO AND W QUEBEC. THE MAIN CONCERN WOULD STILL BE SLIGHTLY
STRONGER S WINDS FRIDAY MORNING W INTO THE AFTERNOON HOURS E.

SATURDAY THROUGH SUNDAY...
A STRONGER 500MB LOW WILL POSITION ITSELF OVER S SASKATCHEWAN
SATURDAY MORNING...AND CENTRAL MANITOBA BY 06Z SUNDAY. THE NEARLY
STACKED SYSTEM SHOULD RESULT THE FRONTAL BOUNDARY OVER THE CWA
LIFTING N AS A WARM FRONT...AND WARMER AIR SURGING N FOR
SATURDAY...WITH WIDESPREAD 80 DEGREE TEMPS AS 850MB TEMPS PUSH INTO
THE 16-18C RANGE. MUCH OF THE CLOUD COVER AND PRECIP SHOULD SHOULD
REMAIN W...CLOSER TO THE NEARING COLD FRONT ACROSS E ND AND W MN.

THE 21/00Z CANADIAN MODEL...WHILE HAVING A SIMILAR IDEA...IS ON THE
NORTHERN FRINGE OF SOLUTIONS. ON THE OTHER HAND...THE 21/06Z GFS IS
A BIT FARTHER SOUTH. THE DIFFERENCE FROM THE 2 IS ROUGHLY
200MI...WHICH IS NOT TOO BAD FOR A 120HR OR MORE FCST. THESE
DIFFERENCES BECOME A BIT MORE PRONOUNCED ACROSS S HUDSON BAY/N
ONTARIO SUNDAY NIGHT...BUT SHOULD NOT IMPACT OUR FCST TOO
GREATLY...AS A TROUGH WILL CONTINUE TO DOMINATE THE UPPER GREAT
LAKES REGION /SATURDAY NIGHT THROUGH AT LEAST SUNDAY NIGHT/.

MONDAY AND TUESDAY...
WRAP AROUND MOISTURE WILL BE POSSIBLE WITH COOLER AIR SLIDING IN ON
NW WINDS OFF THE GFS. HOWEVER...THIS IS HIGHLY DEPENDENT ON WHERE
THE STILL RELATIVELY STACKED LOW DECIDES TO GO. THE MORE PROGRESSIVE
N LOW OFF THE ECMWF STILL TRIES TO AMPLIFY THE SYSTEM TO OUR S
/ACROSS MO/IA/IL/WI/...WITH ANOTHER ROUND OF SHOWERS AND POSSIBLY TS
MONDAY MORNING AND AFTERNOON MAINLY CENTRAL AND E.

THE 21/00Z ECMWF AND 06Z GFS BECOME COMPLETELY OUT OF PHASE OVER THE
PACIFIC NW BY 00Z SUNDAY WRT THE 500MB PATTERN. LUCKILY THIS DOES
NOT SEEM TO NEGATIVELY IMPACT THE UPPER GREAT LAKES REGION UNTIL
MONDAY AFTERNOON/EVENING. AS A RESULT OF AN EXTREMELY LOW CONFIDENCE
FORECAST BEYOND MONDAY...WILL NOT TRY TO DO TOO MUCH OVER CLIMO. BY
DAYBREAK TUESDAY THE GFS HAS A SIZABLE TROUGH ACROSS THE GREAT
LAKES...WHILE THE ECMWF SHIFTS A HIGH AMPLITUDE RIDGE OVERHEAD. THE
MAIN CONCERN WITH A SOLID MODEL BLEND WOULD BE THE ISSUES PRODUCED
BY THE GFS AND CONVECTIVE FEEDBACK. ON A POSITIVE NOTE...THE 12Z
GFS/ECMWF DO LOOK A LITTLE MORE IN AGREEMENT FOR MONDAY AND
TUESDAY...WITH A RIDGE BUILDING IN MONDAY NIGHT INTO TUESDAY. WILL
SEE IF THIS TREND HOLDS UP WITH THE 18Z GFS AND 00Z RUNS.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 131 PM EDT TUE AUG 21 2012

WITH RELATIVELY DRY LOW-LEVELS...VFR CONDITIONS WILL PREVAIL THRU
THIS FCST PERIOD AT KIWD/KCMX/KSAW. MODEST LOW-LEVEL JET ARRIVING
OVERNIGHT TONIGHT WILL LEAD TO POSSIBLE LLWS...MAINLY AT KCMX WHICH
WILL BE CLOSER TO AXIS OF SPEED MAX. WITH DAYTIME HEATING ON WED...
THESE STRONGER WINDS WILL MIX OUT AND RESULT IN A GUSTY WSW WIND.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 412 PM EDT TUE AUG 21 2012

EXPECT SW WINDS VEERING W TO INCREASE UP TO 25 KTS LATER TONIGHT/
EARLY WED...STRONGEST IN THE AREA BETWEEN THE KEWEENAW AND ISLE
ROYALE WHERE TERRAIN ACCENTUATES THIS FLOW...AS A LO PRES TROF
PRESSES INTO LAKE SUPERIOR FROM ONTARIO. LIGHT WINDS WILL THEN
PREVAIL FROM WED AFTERNOON INTO THE WEEKEND BEFORE THE APPROACH OF A
STRONGER DISTURBANCE/COLD FRONT MIGHT CAUSE S-SW WINDS TO INCREASE
UP TO 25 KTS.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KC

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

132 PM EDT TUE AUG 21 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 450 AM EDT TUE AUG 21 2012

WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE DEEP TROF THAT
HAS DOMINATED THE ERN CONUS FOR SEVERAL DAYS IS IN THE PROCESS OF
DEAMPLIFYING AND LIFTING OUT. SHORTWAVE THAT DROPPED THRU THE UPPER
LAKES YESTERDAY AND GENERATED SCT SHRA IS HEADING FOR THE UPPER OHIO
VALLEY. TO THE N...A SHORTWAVE IS MOVING SE THRU NRN MANITOBA TOWARD
NRN ONTARIO. IN RESPONSE...ZONE OF WAA IS SPREADING E ACROSS NRN
ONTARIO EARLY THIS MORNING. SOME CI IS PEELING S TOWARD THE UPPER
LAKES...BUT WAA MID CLOUDS AND ANY SHRA ARE STILL WELL N OF THE FCST
AREA. MAINLY CLEAR SKIES ACROSS THE FCST AREA AND LITTLE/NO WIND
COMBINED WITH THE MOISTURE FROM YESTERDAYS SHRA HAS LED TO RECENT
DEVELOPMENT OF SHALLOW PATCHY FOG AS A NUMBER OF OBS ARE SHOWING
WIDELY FLUCTUATING VIS.

MAIN FCST CONCERN IN THE SHORT TERM IS POTENTIAL OF CONVECTION
TONIGHT AS TRAILING SFC COLD FRONT FROM AFOREMENTIONED SHORTWAVE
SAGS S TOWARD THE UPPER LAKES. TODAY WILL BE A DRY DAY AS MAIN PUSH
OF WAA CONTINUES TO BE EASTWARD ACROSS NRN ONTARIO AHEAD OF
SHORTWAVE DROPPING SE INTO NRN ONTARIO. UNDER MOSTLY SUNNY
SKIES...MIXING UPWARDS OF 800MB OR SO ON FCST SOUNDINGS YIELDS MAX
TEMPS MAINLY IN THE MID/UPPER 70S. SOME LOCAL COOLING WILL OCCUR
NEAR THE GREAT LAKES.

TONIGHT...850MB THERMAL RIDGE AND MAIN ZONE OF WAA SINKS S INTO THE
UPPER LAKES. AXIS OF MODEST WRLY LOW-LEVEL JET OF 20-30KT REMAINS
MOSTLY JUST N OF UPPER MI...BUT PROXIMITY IS PROBABLY CLOSE ENOUGH
TO WARRANT A SLIGHT CHC OF SHRA/TSRA OVER THE KEWEENAW LATE TONIGHT.
CHC POPS WERE UTILIZED TO THE N ACROSS LAKE SUPERIOR. PER FCST
SOUNDINGS...LOW-LEVELS REMAIN DRY WITH MOISTURE CONFINED TO ROUGHLY
ABOVE 750MB. MIGHT BE ABLE TO GET 100-200J/KG OF CAPE FOR PARCELS
LIFTED FROM THE ELEVATED MOIST LAYER. GIVEN THE LACK OF
INSTABILITY...THE ELEVATED CONVECTION MAY HAVE TROUBLE PRODUCING
PCPN THAT WILL REACH THE GROUND. WITH S/SW WINDS STIRRING IN THE
DOWNSLOPE AREAS NEAR LAKE SUPERIOR...TEMPS THERE MAY NOT FALL BLO
60F TONIGHT. EXPECT 50S ELSEWHERE. SHOULD BE ENOUGH DECOUPLING FOR
MINS DOWN TO AROUND 50F IN THE TRADITIONAL COLD SPOTS.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 450 AM EDT TUE AUG 21 2012

LARGE SCALE PATTERN FEATURES TROUGH OVER GREAT LAKES CONTINUING TO
BREAK DOWN INTO MORE ZONAL FLOW PATTERN BY LATE THIS WEEK. THIS
ALLOWS SHORTWAVE TROUGH EMERGING FROM TROUGH AXIS FROM GULF OF
ALASKA TO PACIFIC NORTHWEST TO PROPEL EAST INTO NORTHERN PLAINS
AND UPPER MISSISSIPPI RIVER VALLEY BY FRIDAY. AHEAD OF THE NORTHERN
PLAINS SHORTWAVE...SURFACE TROUGH OVER NORTHERN ONTARIO WILL DROP
INTO UPPER GREAT LAKES ON WEDNESDAY AND BECOME FAIRLY STATIONARY OVER
UPPER MICHIGAN THROUGH FRIDAY. COULD SEE AT LEAST A COUPLE INTERVALS
OF SHRA/TSRA THURSDAY INTO FRIDAY AS THE LARGER SCALE UPPER TROUGH
INTERACTS WITH THE SURFACE TROUGH.

MAJORITY OF MOISTURE ALONG AND AHEAD OF SURFACE TROUGH ON WEDNESDAY
IS H7-H5 WITH LIFT ACTING ON THIS LAYER OF MOISTURE. VERY LITTLE
MOISTURE IS PRESENT BLO H7...SO FOR WEDNESDAY HAVE KEPT POPS TIED
INTO THE AREA OF H7-H5 MOISTURE/UVM AND H7 MOISTURE ADVECTION.
STRONGEST PVA FM SHORTWAVE TRACKING ACROSS ONTARIO STAYS WELL TO THE
NORTH AND EAST OF UPR MICHIGAN...AS DOES DIVERGENCE ALOFT FM JET
STREAK PASSING JUST SOUTH OF JAMES BAY. OVERALL THERE IS NOT A LOT OF
FORCING TO JUSTIFY POPS OVER MOST OF CWA. KEPT SOME POPS IN THE EAST
CWA...BUT REMOVED POPS OVER THE CENTRAL CWA. GIVEN EXPECTED THINNING
MID CLOUDS BY AFTERNOON SHOULD SEE TEMPS WARM NICELY WITH STRONGER
1000-850MB SW WINDS PRESENT JUST AHEAD OF BOUNDARY DROPPING INTO
UPPER GREAT LAKES. NAM/GFS SOUNDINGS POINT TO MIXING UP TO 850-800MB.
MIXING TO H85 YIELDS RETURN TO THE 80S FOR MUCH OF THE AREA...BOOSTED
FURTHER BY MINIMAL LAKE BREEZES AS STRONGER 950-925MB SW WINDS HOLD
THROUGH THE AFTN. WITH ENOUGH SUNSHINE...IT IS LIKELY THAT SOME
AREAS OF CWA SEE TEMPS INTO THE MIDDLE 80S. MINIMUM IN PRECIP CHANCE
CONTINUES THROUGH MOST OF WEDNESDAY NIGHT AND MAYBE INTO THURSDAY
MORNING AS WELL AS MAIN FOCUS FOR SHRA/TSRA WILL BE TIED INTO LEAD
SHORTWAVE PUSHING INTO MINNESOTA BY 12Z THURSDAY OUT AHEAD OF H85-H5
TROUGH MOVING ACROSS THE NORTHERN PLAINS.

CHANCES FOR SHRA/TSRA INCREASE BY THURSDAY AFTERNOON AS THE LEAD
SHORTWAVE PRESSES INTO UPPER GREAT LAKES AND INTERACTS WITH
TEMPERATURE AND MOISTURE ADVECTION INTO SURFACE BOUNDARY PRESENT
OVER THE AREA. MAX H85 MOSITURE ADVECTION AND PVA FROM THE WAVE
COINCIDE OVER WEST HALF OF UPR MICHIGAN ON THURSDAY. INCREASED POPS
OVER THE WEST BUT ALSO WENT WITH SLIGHT CHANCE FOR ALL AREAS DUE TO
THE LOW-LEVEL TROUGH IN THE VICINITY. SHOWED WARMEST TEMPS ON
THURSDAY OVER THE EAST AS THERE IS HIGHER PROBABILITY IT REMAINS
MOSTLY SUNNY THERE INTO THE EARLY-MID AFTERNOON. TEMPS WILL RANGE
FROM THE MID 70S AT THE COOLEST AND WITH ENOUGH SUNSHINE MAY BUMP
INTO THE MID 80S OVER THE EAST. SEEMS THAT BETTER CHANCES OF
SHRA/TSRA THURSDAY NIGHT SET UP MORE OVR LK SUPERIOR ON NOSE OF H85
JET AND CLOSER TO TRACK OF LEAD SHORTWAVE LIFTING INTO ONTARIO.
CANNOT RULE OUT CHANCES ANYWHERE THOUGH AS AGAIN...THE SURFACE FRONT
IS STILL FORECAST CLOSE TO UPR MICHIGAN. INTO FRIDAY...BEFORE IT
LOOKED LIKE THIS WOULD BE THE DAY OF GREATEST RAIN CHANCES. NOT SO
CLEAR CUT NOW THOUGH...AND UNFORTUNATELY THIS FORECAST UNCERTAINTY
PERSISTS RIGHT THROUGH THE UPCOMING WEEKEND AS WELL. STILL PREFER TO
HOLD ONTO THE IDEA FM THE ECMWF AND GEM-NHEM WITH ANOTHER BOUT OF
H85 MOISTURE ADVECTION KICKING OFF SHRA/TSRA ALONG H5 TROUGH AXIS
OVR UPR MICHIGAN DURING PEAK HEATING. STRONGEST HEIGHT FALLS THEN
SHIFT TO THE NORTH AND EAST OF CWA FRIDAY NIGHT SO EXPECT GREATEST
RAIN CHANCES TO PROBABLY DO SO AS WELL.

CURRENT FORECAST FOR SATURDAY AND SUNDAY FEATURES CHANCES FOR
SHRA/TSRA BUT MODEL TRENDS NOW SUGGEST IT MAY END UP BEING MOSTLY
FREE OF RAIN...AT LEAST SATURDAY AND SATURDAY NIGHT. ONLY MODEL THAT
HITS POPS UP THIS WEEKEND IS THE GFS...BUT SINCE GFS SOLUTION
CONTINUES TO BE INFLUENCED BY CONVECTIVE FEEDBACK...HPC HAS TOSSED
IT OUT FOR THIS FORECAST CYCLE. BASED ON POSITION OF INCOMING UPPER
TROUGH OVR SCNTRL CANADA...UPPER JET...SFC FRONT AND H85-H7 MOISTURE
ADVECTION...BETTER SHRA/TSRA CHANCES WOULD SEEM TO SPLIT MORE AROUND
UPR MICHIGAN THROUGH THE WEEKEND. LATER FORECASTS MAY NEED TO TREND
DRIER. LACK OF CLOUDS/SHRA/TSRA WOULD LEAD TO WARMER TEMPS AS WELL
SINCE H85 TEMPS ARE A WARM 15-18C AND LOW-LEVEL WINDS ARE SOUTHWEST
AHEAD OF LARGER SCALE TROUGH. CURRENT FORECAST POINTS TO UPPER
70S-LOWER 80S WITH MOSTLY CLOUDY SKIES AND A CHANCE FOR RAIN. WHEN
IN REALITY IT VERY WELL COULD END UP MOSTLY SUNNY WITH HIGHS IN THE
MID-UPPER 80S. BY LATE SUNDAY...BETTER CHANCES OF SHRA/TSRA PRESS
ACROSS CWA WITH COLD FRONT TIED TO UPPER TROUGH MOVING FM MANITOBA
INTO ONTARIO. EXACT TIMING WITH THIS FRONT WILL REMAIN A QUESTION
UNTIL WE GET CLOSER TO THE WEEKEND THOUGH...SO KEPT WITH CONSENSUS
APPROACH FOR POPS AT THIS TIME.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 131 PM EDT TUE AUG 21 2012

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 AM EDT TUE AUG 21 2012

LIGHTER WINDS BECOMING WEST SOUTHWEST AND INCREASE TO 15-25 KTS
LATER TODAY INTO TONIGHT AS FRONT DROPPING IN FROM ONTARIO TIGHTENS
PRESSURE GRADIENT. STRONGEST WINDS WILL OCCUR OVER WEST AND NORTH
CENTRAL LK SUPERIOR BETWEEN ISLE ROYALE AND TIP OF KEWEENAW. WINDS
RELAX ON WEDNESDAY AS PRESSURE GRADIENT SLACKENS. EXPECT WINDS TO
INCREASE AGAIN FOR THE UPCOMING WEEKEND AS STRONGER LOW PRESSURE
SYSTEM AND FRONT APPROACH FROM THE PLAINS. COULD SEE SOUTHERLY
GUSTS TO 25 KTS OVER EASTERN SECTIONS SATURDAY NIGHT INTO SUNDAY
JUST AHEAD OF THE FRONT.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...KC
MARINE...JLA

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

740 AM EDT TUE AUG 21 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 450 AM EDT TUE AUG 21 2012

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 450 AM EDT TUE AUG 21 2012

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 740 AM EDT TUE AUG 21 2012

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 AM EDT TUE AUG 21 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...JLA

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

456 AM EDT TUE AUG 21 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 450 AM EDT TUE AUG 21 2012

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 450 AM EDT TUE AUG 21 2012

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 137 AM EDT TUE AUG 21 2012

EXPECT VFR CONDITIONS THROUGH THE FCST PERIOD WITH RELATIVELY DRY
LOW LEVELS AS HIGH PRES BUILDS INTO THE REGION. WEAK WRLY DOWNSLOPE
FLOW AT KSAW WILL MINIMIZE ANY POTENTIAL FOR FOG FORMATION AFTER SOME
MOISTENING WITH RAIN SHOWERS THAT OCCURRED MON AFTERNOON.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 AM EDT TUE AUG 21 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA

AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

610 PM CDT WED AUG 22 2012

.UPDATED FOR 00Z AVIATION DISCUSSION BELOW...

.DISCUSSION...

TONIGHT AND THURSDAY...STRONG LLJ AND MOISTURE SURGING FROM THE S
IS MAKING FOR A RETURN TO WARMER TEMPERATURES ALONG WITH AN ATMOS
WITH A HIGHER MOISTURE CONTENT. THE PUSH OF THE WMFNT FROM ERN
SD/NW IA INTO SW MN HAS BEEN EVIDENT BY TEMPS HITTING 90 DEGREES
IN FAR SWRN MN...BUT ALSO DUE TO THE NW-SE ALIGNMENT OF BANDED
SHWRS/TSTMS THAT HAVE BEEN SLOWLY PUSHING THRU WRN AND CENTRAL
PORTIONS OF MN THIS AFTN. SREF/WRF/HRRR ALL INDICATED THAT WHAT
WAS A SMALL BATCH OF SHWRS THIS MRNG WOULD ELONGATE AND INTENSIFY
THIS AFTN OVER CENTRAL INTO ERN MN...AND THAT HAS BEEN THE CASE
TDA. GIVEN THE STRONG INFLUX OF MOISTURE AND STRONGER JETTING...
THESE BANDS OF PRECIP CAN BE EXPECTED TO CONTINUE SHIFTING E-NE
THROUGH THIS EVENING. THE WMFNT WILL SLOWLY LIFT NE OVERNIGHT...
NUDGING THROUGH MUCH OF THE MPX CWFA BY DAYBREAK. A LOW PRES
CENTER ASSOCIATED WITH THE WMFNT WILL SPIN UP OVER ERN SD INTO
FAR SW MN...HELPING ENHANCE LIFT FROM THE SW. THIS LOW WILL SLOG
ITS WAY NE...DRAGGING CLUSTERS OF SHWRS/TSTMS WITH IT OVER MUCH OF
SRN MN. TIMING IS A BIT PROBLEMATIC AS IS LOCATION SINCE THIS WILL
NOT BE A STRATIFORM RAIN EVENT SO HAVE CAPPED POPS AT 40 FOR
TONIGHT BUT THEN NUDGED POPS UP TO 50 FOR TMRW GIVEN GREATER
INSTABILITY PARAMETERS BY TMRW AFTN. AS FOR TEMPS...CONDITIONS
WILL CERTAINLY BE MILD BUT TEMPERATURE CURVES HAVE BEEN THROWN OFF
A BIT BY THE BANDS OF RAIN THAT HAVE PUSHED THROUGH THE AREA TDA.
WILL LOOK FOR LOWS TO EVENTUALLY BOTTOM OUT IN THE 60S TNGT...
HIGHEST ARND THE TWIN CITIES METRO. HIGHS TMRW WILL REACH THE MID
40S IN NRN AND ERN PORTIONS OF THE MPX CWFA WHILE SRN AND WRN
PORTIONS HIT THE UPPER 80S...WITH A FEW 90-DEGREE READINGS
POSSIBLE.

THURSDAY NIGHT THROUGH SATURDAY...THE WMFNT WILL GRADUALLY
DISSIPATE THU NIGHT N OF THE MPX CWFA...AND WILL BE FOLLOWED BY
ANOTHER WEAK WMFNT THAT WILL SHIFT THRU THE REGION FRI AND FRI
NIGHT WHILE A CDFNT BECOMES MORE ORGANIZED OVER THE NRN PLAINS.
THIS CDFNT WILL PUSH INTO THE DAKOTAS SAT AND REACH THE ERN
DAKOTAS SAT NIGHT. COMBINED WITH A FAIRLY PROGRESSIVE UPPER AIR
PATTERN...THE END OF THE WEEK INTO THE WEEKEND WILL BE A BIT
MESSY. A COMMON THEME AMONG THE EC/GFS/GEM HAS BEEN A SPLIT FLOW
PATTERN THAT SHOWS DIFFERENT LOCATIONS OF THE NRN AND SRN STREAMS
MERGING OVER THE GREAT LAKES. THE DEEP MOISTURE PROFILES REMAIN IN
PLACE AS DOES A DECENT LLJ ALONG WITH SEVERAL SHORTWAVE
DISTURBANCES ALONG PROGGED TO PUSH THROUGH. MODELS GENERALLY PIN
DOWN 2 TIMEFRAMES FOR BEST SHOT AT PRECIP - LATE THU NIGHT AND SAT
AFTN. THOSE PERIODS CONTAIN 50/60 POPS WITH LESSER CHCS FOR OTHER
PERIODS IN THE MID-TERM. THE OTHER ITEM OF NOTE IS THE SWING THAT
TEMPERATURES WILL HAVE IN THIS PERIOD. WITH THE AREA MAINLY
BECOMING WARM-SECTORED...HIGHS ON FRI WILL CLIMB TO THE LOWER 90S
FOR MUCH OF THE MN PORTION OF THE CWFA...WHILE WRN WI HITS THE UPR
80S TO NEAR 90. LOWS ONLY DROP TO THE 60S AND LOWER 70S FRI NIGHT.
SOME CAA IS EXPECTED FOR SAT UNDER DEVELOPING NW FLOW...AND THIS
COMBINATION WILL CUT INTO MAX TEMPS ON SAT. HIGHS WILL ONLY REACH
THE LOW-MID 80S SAT.

SUNDAY THROUGH TUESDAY...A FAIRLY PRONOUNCED CDFNT WILL PUSH
THROUGH THE UPPER MISS RIVER VALLEY REGION EARLY SUNDAY...
FOLLOWED BY RIDGING BOTH AT THE SFC AND ALOFT MON INTO TUE. THIS
WILL ALLOW FOR A DRYING OUT PERIOD FOR THE EARLY PORTION OF NEXT
WEEK. SOME SHWRS MAY LINGER IN ERN PORTIONS OF THE AREA
SUN...OTHERWISE SKIES WILL BE GRADUALLY CLEARING OUT. THE DEEP
RIDGING WILL ALLOW FOR A SLIGHT COOLDOWN IN TEMPERATURES...BUT
STILL ABOVE NORMAL. HIGHS WILL DROP TO THE LOWER 80S WITH LOWS IN
THE UPPER 50S TO LOWER 60S.

.AVIATION.../00Z TAF ISSUANCE/

ISOLD SHRA/TSRA WITH WAA WIND LIFTING NORTHEAST OVER EASTERN AREAS
THIS EVENING. WILL LIKELY CONTINUE TO WEAKEN. WILL MENTION SHRA AT
KRNH EARLY AND VCSH AT KEAU BEFORE 05Z. THEN FOCUS TURNS TO THE
SOUTHWEST...CLOSER TO THE SURFACE WARM FRONT WHICH IS MAKING SLOW
PROGRESS NORTHEAST. LOCAL WRF AND THE LATEST AVBL HRRR IS
INDICATING THIS ACTIVITY WILL ONCE AGAIN DEVELOP SOUTHWEST AFTER 04Z
AND THEN SPREAD EAST OVERNIGHT. WILL LIKELY BE ELEVATED ONCE AGAIN
WILL A SMALL THREAT OF HAIL. WILL TRY AND TIME ACTIVITY EAST MAINLY
AFTER 05Z. WILL CARY VCSH WITH THE EXCEPTION OF KRWF AFTER 04Z.
THIS MAY CONTINUE OVER THE WEST INTO THE MORNING HOURS WITH
REDEVELOPMENT ALONG SURFACE COLD FRONT AS IT WORKS EAST DURING THE
LATE AFTERNOON/EVENING. THIS MAY MEAN DEVELOPMENT JUST EAST OF
KAXN IN THE AFTERNOON...AS SURFACE WINDS BECOME MORE WESTERLY.
WILL MENTION SOME PROB30 TSRA OVER MUCH OF THE EAST DEVELOPING IN
THE AFTERNOON...AND TEMPO AT KRWF. APPEARS SURFACE WINDS WILL BECOME
MORE SOUTHERLY AS WARM FRONT LIFTS THROUGH KRWF EARLY...AND PERHAPS
FARTHER NORTH INTO THURSDAY MORNING. MAY SEE GUSTS DEVELOP OVER
SOUTHERN AREAS IN WARM SECTOR...BUT LEFT OUT FOR NOW BECAUSE OF
CLOUDS EXPECTED.

KMSP...SHRA MOVING EAST AND DISSIPATED THIS EVENING. WILL SEE SOME
POSSIBLE REDEVELOPMENT AFTER 05Z AS LOW LEVEL JET CONTINUES TO
INTENSIFY OVERNIGHT. WILL MENTION VCSH AFTER 05Z FOR NOW. WILL
WAIT AND SEE IF ACTIVITY DEVELOPS TO THE SOUTHWEST FOR THE UPDATE.
MAY SEE SOME ACTIVITY AROUND IN THE MORNING WITH MORE REDEVELOPMENT
EXPECTED AFTER 22Z THURSDAY - WITH PROB30 TSRA ADDED INTO THURSDAY
EVENING FOR NOW. SOUTHEAST SURFACE WINDS AHEAD OF SURFACE WARM
FRONT...MAY BECOME MORE SOUTHERLY LATER TONIGHT AS NEXT CHANCE OF
SHRA MOVES IN.

/OUTLOOK FOR KMSP/
FRIDAY...VFR. WIND SSW 5 TO 10 KTS.
SATURDAY...VFR WITH MVFR SHRA/TSRA POSSIBLE. WIND S 10 TO 15 KTS.
SUNDAY...MAINLY VFR WITH MVFR SHRA/TSRA POSSIBLE IN THE MORNING.
WIND BECOMING WEST 5 TO 10 KTS.

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

JPC/DE

AREA FORECAST DISCUSSION

NWS TWIN CITIES/CHANHASSEN MN

619 AM CDT TUE AUG 21 2012

.UPDATE...

12Z AVIATION DISCUSSION ADDED BELOW.

.DISCUSSION...

ONE MORE FINE WEATHER DAY IN STORE ACROSS THE REGION TODAY AS HIGH
PRESSURE SLIPS SLOWLY SOUTHEAST. THE LOW LEVEL FLOW WILL BEGIN TO
INCREASE FROM THE SOUTHWEST TONIGHT...WITH RATHER STRONG THETA-E
ADVECTION DEVELOPING ACROSS SOUTHWEST MN AFTER MIDNIGHT. THE NAM
310K THETA SURFACE HAS PLENTY OF UPGLIDE DEVELOPING AS WELL. THIS
COMBINED WITH MID LEVEL INSTABILITY SHOULD YIELD SOME SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS THE FAR SOUTH. THE ACTIVITY MAY
GRAZE THE METRO AREA LATE WEDNESDAY MORNING WITH A CHANCE OF
SHOWERS AND THUNDERSTORMS ACROSS WEST CENTRAL WI WEDNESDAY
AFTERNOON AND EVENING. HIGHS TODAY WILL GENERALLY BE IN THE
LOWER 80S WITH HIGHS CLIMBING INTO THE MIDDLE TO UPPER 80S ON
WEDNESDAY. THE WARMEST READINGS ON WEDNESDAY WILL BE ALONG AND
SOUTH OF THE MN RIVER.

THE UPPER AIR PATTERN WILL CHANGE FROM NORTHERLY TO WESTERLY OVER
THE NEXT 24 HOURS. THIS WILL ALLOW A SERIES OF SHORT WAVES TO
IMPACT THE REGION. THE FIRST WILL BE LATE WEDNESDAY NIGHT AND
THURSDAY...AIDING IN MORE WIDESPREAD SHOWERS AND THUNDERSTORMS.
THE WESTERN HALF OF THE FA LOOKS MOST FAVORABLE FOR RAIN ON
THURSDAY WITH THE EASTERN HALF THURSDAY NIGHT. THE TIMING ON THIS
FEATURE REMAINS CONSISTENT WITH THE VARIOUS SOLUTIONS.

A SECOND WAVE FOR THE WEEKEND HAS LESS AGREEMENT WITH THE ECMWF
DEEPER AND SLOWER ALOFT. WHAT WOULD BE MAINLY A CHANCE OF SHOWERS
AND THUNDERSTORMS ON SATURDAY ON THE GFS TURNS INTO A PROLONGED
EVENT THAT COULD LAST INTO MONDAY OVER EASTERN AREAS ON THE ECMWF.
THE TWO SOLUTIONS MAY REPRESENT THE EXTREMES WITH THE GEM NOT AS
FAST AS THE GFS BUT NOT AS DEEP AND SLOW AS THE ECMWF. THIS
SOLUTION WOULD FAVOR LESS PRECIPITATION OVER THE WESTERN FA ON
SUNDAY WITH DIMINISHING POPS EAST SUNDAY NIGHT. COLLABORATION
YIELDED A DRY FORECAST FOR MONDAY. HIGHS DURING THE WEEKEND WILL
SLIP BACK TO NEAR NORMAL VALUES.

ON A SIDE NOTE...MSP IS RUNNING A 1.8 DEGREES BELOW NORMAL FOR THE
MONTH. WE HAVE NOT HAD A BELOW NORMAL MONTH SINCE MAY 2011. IT
LOOKS AS THOUGH MANY OF THE DAYS LEFT IN AUGUST WILL BE AT OR
ABOVE NORMAL...BUT WILL IT BE ENOUGH?

.AVIATION.../12Z TAF ISSUANCE/

HIGH PRESSURE WILL BE SLIDING SE OF THE MPX AREA TODAY...WITH 5-10
KT SW WINDS SETTING UP AS A RESULT. COMPARING KMPX VAD WIND DATA
WITH MODEL SOUNDINGS...THE RAP LOOKS TO BE VERIFYING BEST THIS
MORNING WITH DIRECTIONS...SO FOLLOWED IT FOR DIRECTIONS
TODAY. THIS RESULTED IN DIRECTIONS WITH A BIT MORE OF A WEST
COMPONENT THAN WHAT LAMP HAS. TOWARD 12Z WED A WARM FRONT WILL
BEGIN LIFTING NORTH TOWARD SW MN. BULK OF CLOUD COVER AND ANY
PRECIP AHEAD OF IT LOOK TO COME IN JUST AFTER THIS TAF
PERIOD...BUT WILL LIKELY START TO SEE AN INCREASE IN MID CLOUDS
TOWARD THE END OF THE RWF/MSP TAF PERIODS.

KMSP...FEW CONCERNS AGAIN TODAY WITH HIGH PRESSURE STILL IN
CONTROL. LOOKING AT MPX VAD WINDS...MAY HAVE A FEW OBS THIS
MORNING CLOSER TO 270 IN DIRECTION BEFORE TRENDING TOWARD 220 THIS
AFTERNOON. VFR CONDS CAN BE EXPECTED THROUGHOUT. WINDS WILL BE
STAYING UP AROUND 5 KTS TONIGHT...SO RIVER VALLEY FOG CONCERNS
WILL BE LOW.

/OUTLOOK FOR KMSP/
.WEDNESDAY...VFR. A FEW AFTERNOON TSRA POSSIBLE. WIND SSE 10 KTS
.THURSDAY...VFR. TSRA CHANCES INCREASING IN THE EVENING. WIND S 10 KTS
.FRIDAY...VFR. TSRA CHANCES DIMINISHING IN MORNING. WIND SW 10 KTS

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

RAH/MPG

AREA FORECAST DISCUSSION

NWS HASTINGS NE

1053 PM CDT WED AUG 22 2012

.AVIATION...06Z KGRI TAF...VRF CONDITIONS ARE EXPECTED TO PREVAIL
AT KGRI FOR THE MAJORITY OF THE TAF PERIOD...WITH A TSRA AND
LOWERED CIGS BECOMING POSSIBLE AFT 24/00Z. OVERNIGHT...EXPECT
SOUTHERLY WINDS NEAR 10 KTS TO CONTINUE TO PREVAIL AT THE TERMINAL
WITH INCREASING MID/HIGH LEVEL CLOUDS SPILLING OFF THE CONVECTION
TO OUR WEST. AFTER ABOUT 23/14Z...EXPECT WINDS TO BEGIN TO
INCREASE AGAIN OUT OF THE SOUTH...EVENTUALLY GUSTING AS HIGH AS
20 KTS AF 23/17Z. WITH AN APPROACHING MID LEVEL
DISTURBANCE...EXPECT CLOUDS TO THICKEN AT THE TERMINAL THROUGHOUT
THE DAY...EVENTUALLY LOWERING TO AROUND 10KFT BY 23/17Z. BEST
CHANCE FOR PRECIP WITH THIS DISTURBANCE APPEARS AFT 24/00Z...SO
WILL INCLUDE A PROB30 GROUP AFT 24/00Z TO ACCOUNT FOR INCREASING
CHANCES.

.PREV DISCUSSION... /ISSUED 743 PM CDT WED AUG 22 2012/

UPDATE...WENT AHEAD AND CANCELLED THE RED FLAG WARNING ABOUT AN
HOUR EARLY AS TEMPERATURES HAVE BEGUN TO FALL AND RELATIVE
HUMIDITIES ARE ON THE RISE. OTHERWISE...MADE A FEW ADDITIONAL
CHANGES TO THE FORECAST PACKAGE TO REFLECT CHANCES FOR PRECIP
OVERNIGHT AS CONVECTION ROLLS OFF THE HIGH PLAINS. FOLLOWED FAIRLY
CLOSELY TO HRRR GUIDANCE...BRINGING A FEW SHOWERS IN THE LATE
EVENING ACROSS THE WESTERN FRINGES OF THE FORECAST AREA...AND
KEEPING VERY SMALL POPS ACROSS THE REMAINDER OF THE AREA DURING
THE OVERNIGHT HOURS. OTHERWISE...MADE NO TWEAKS BEYOND 23/12Z AT
THIS TIME.

PREV DISCUSSION... /ISSUED 316 PM CDT WED AUG 22 2012/

SHORT TERM...TONIGHT THROUGH THURSDAY AFTERNOON. PRIMARY CONCERN
WILL BE SMALL PRECIPITATION CHANCES OVERNIGHT AND DURING THE DAY
ON THURSDAY.

CURRENT WATER VAPOR IMAGERY...UPPER AIR AND WIND PROFILER DATA
SHOWING WESTERN U.S. RIDGE HAS BROKEN DOWN IN THE PAST COUPLE OF
DAYS AS LOW PRESSURE MOVED ONTO THE PACIFIC COAST. THE ENERGY HAS
SPLIT WITH ONE WAVE MOVING ACROSS NORTH CENTRAL MONTANA AND THE
CANADIAN PROVINCES...WHILE A SOUTHERN WAVE HAS DROPPED INTO SOUTH
CENTRAL CALIFORNIA. 60 METER HEIGHT FALLS NOTED WITH THE NORTHERN
WAVE AT 500 MB WHILE WEAKER SOUTHERN SYSTEM SHOWING 20-30 METER
HEIGHT FALLS. AT THE SURFACE...LEE TROUGH CONTINUES TO STRENGTHEN
ACROSS THE AREA WITH ABOUT A 9 MB PRESSURE GRADIENT ACROSS NEB & KS
AT 17Z. NAM OVERDONE WITH SURFACE DEEPENING AS NOTED IN 15 AND 18Z
PROGS...ALTHOUGH WINDS STILL PLENTY STRONG RUNNING 15 TO 20 MPH WITH
GUSTS TO 30 BY EARLY AFTERNOON. DEWPOINTS ALSO HIGHER THAN
EXPECTED...IN THE MID 50S AT 17Z...AND THIS MAY KEEP US FROM HITTING
RED FLAG CRITERIA THIS AFTERNOON AND MAY ALSO KEEP HIGH TEMPS A FEW
DEGREES LOWER THAN FCST FOR THIS AFTERNOON.

MODELS SIMILAR IN SOME RESPECTS WITH MOVING THE WAVES NOTED ABOVE
EASTWARD WITH BOTH GFS AND NAM KICKING OUT A MORE SUBTLE SHORTWAVE
AHEAD OF THE SOUTHERN SYSTEM THAT IS SLATED TO PUSH ACROSS SOUTHERN
NEB ON THURSDAY. GFS LOOKS TO HAVE SOME CONVECTIVE FEEDBACK ISSUES
THURS AFTERNOON AS IT DEVELOPS A VORTICITY BULLS EYE ACROSS THE KS
PART OF OUR CWA LATE THURS AFTN INTO THE OVERNIGHT. THIS CAUSES
THE MODEL TO GENERATE WAY TOO MUCH RAINFALL IN THAT AREA. THE
OTHER FEATURE OF NOTE IS A SURFACE TROUGH AND DRY LINE THAT EXTEND
JUST WEST OF OUR CWA BY THURSDAY NOON. POSSIBLE THAT THIS COULD BE
AN AREA WHERE STORMS DEVELOP AND THEN DRIFT EAST ACROSS OUR
REGION. CAPE VALUES IN THE 2000+ J/KG RANGE WITH DEEP LAYER SHEAR
PROGGED TO BE 25-30 KT. IF STORMS DO DEVELOP A FEW STRONG TO
SEVERE NOT OUT OF THE QUESTION. ONE OF THE ISSUES HERE IS WHEN AND
WHERE ANY MID LEVEL SUPPORT WILL BE.

REGARDING FIRE WEATHER POTENTIAL FOR THURSDAY...DEWPOINTS CONTINUE TO
HOLD HIGHER THAN EXPECTED THIS AFTERNOON...AND TOMORROW APPEARS TO
HAVE EVEN HIGHER SURFACE DEWPOINTS WITH RETURN FLOW IN PLACE. SO
WHILE WINDS WILL STILL BE UP ON THURSDAY...PROGGED RH VALUES WILL BE
A SOMEWHAT HIGHER THAN THE 20 PERCENT THRESHOLD.

LONG TERM...STARTING 00Z FRIDAY. GUIDANCE SUGGESTS THE OVERALL MID
AND UPPER LEVEL FLOW PATTERN WILL REMAIN QUASI-ZONAL FRIDAY
THROUGH SUNDAY...WITH UPPER LEVEL RIDGING EXPECTED TO BUILD IN
ACROSS THE CENTRAL PLAINS MONDAY ONWARD. A RELATIVELY ACTIVE MID
LEVEL PATTERN IS EXPECTED TO PRESENT ITSELF TO OUR AREA LATE THIS
WEEK AND INTO THE EARLY PART OF NEXT WEEK...WITH PRECIPITATION
CHANCES LITTERING MUCH OF THE EXTENDED FORECAST PERIOD.
PRECIPITATION CHANCES ARE IN PLACE ACROSS MUCH OF THE CWA 00Z-12Z
FRIDAY AS THE AXIS OF A ~45KT 850MB JET STREAK SETS UP FROM
SOUTHWEST KANSAS INTO SOUTHEAST NEBRASKA. WENT AHEAD WITH 30%-40%
POPS ACROSS THE CWA AS A RESULT. ALTHOUGH QPF FIELDS FROM THE
NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL SUGGEST PRECIPITATION
WILL BE POSSIBLE ACROSS MOST ALL OF THE CWA DURING THIS TIME
PERIOD...WENT AHEAD AND RELEGATED THE HIGHEST POPS ACROSS
SOUTHEASTERN PORTIONS OF THE CWA AS THIS IS WHERE THE STRONGEST
LOW LEVEL THERMAL ADVECTION AND MOISTURE CONVERGENCE IS EXPECTED
TO RESIDE. SHOWER AND THUNDERSTORM ACTIVITY SHOULD BE ON THE
DOWNWARD TREND HEADING INTO THE DAY FRIDAY AS THE LOW LEVEL JET
ALSO DIMINISHES POST-SUNRISE. THAT BEING SAID...THERE ARE
INDICATIONS FROM THE NAM AND OPERATIONAL GFS THAT AN APPROACHING
MID LEVEL SHORT WAVE MAY BRING ABOUT ENOUGH MID LEVEL THERMAL
ADVECTION FOR CONVECTIVE REDEVELOPMENT ACROSS THE MUCH OF THE CWA
HEADING INTO THE AFTERNOON HOURS FRIDAY. GIVEN ALL THIS...WENT
AHEAD WITH 30% POPS ACROSS OUR SOUTHEASTERN CWA TO ACCOUNT FOR
DIMINISHING MORNING CONVECTION...WITH 20% POPS IN EXISTENCE
ELSEWHERE TO ACCOUNT FOR THE POSSIBILITY OF ISOLATED SHOWER AND
THUNDERSTORMS ACTIVITY HEADING INTO THE AFTERNOON HOURS. A 40-50KT
850MB JET STREAK IS THEN FORECAST TO SET UP FROM SOUTH CENTRAL
KANSAS INTO SOUTHEASTERN NEBRASKA FRIDAY NIGHT INTO SATURDAY
MORNING THUS RESULTING IN FURTHER PRECIPITATION CHANCES. MUCH LIKE
THE THURSDAY NIGHT/FRIDAY MORNING CONVECTION...THE BEST LOW LEVEL
THERMAL ADVECTION AND MOISTURE CONVERGENCE ARE EXPECTED TO RESIDE
CLOSER TO OUR SOUTHEASTERN CWA. SO...EVEN THROUGH QPF FIELDS FROM
THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL SUGGEST
PRECIPITATION WILL BE POSSIBLE ACROSS MOST ALL OF THE CWA...OPTED
TO RELEGATE THE HIGHEST POPS...AROUND 40%...ACROSS OUR
SOUTHEAST...WITH DECREASING POPS AS ONE MOVES NORTHWEST ACROSS THE
CWA. IN ADDITION TO THE LOW LEVEL JET AXIS...MID LEVEL THERMAL
ADVECTION AHEAD OF THE APPROACHING MID LEVEL SHORT WAVE MAY ALSO
ENCOURAGE ADDITIONAL PRECIPITATION PRODUCTION ACROSS MUCH OF THE
CWA...BUT STILL FELT IT WISE TO RELEGATE THE HIGHEST POPS ACROSS
OUR SOUTHEAST. SHOWER AND THUNDERSTORM ACTIVITY ARE CURRENTLY
EXPECTED TO PERSIST HEADING INTO THE DAYTIME HOURS
SATURDAY...ESPECIALLY THROUGH 18Z. LINGERING PRECIPITATION DUE TO
THE DIMINISHING LOW LEVEL JET WILL CERTAINLY BE AN ISSUE...BUT THE
DPVA AND MID LEVER THERMAL ADVECTION JUST AHEAD OF THE MID LEVEL
TROUGH AXIS PUSHING ACROSS THE AREA ARE ALSO EXPECTED TO BRING A
DECENT DOSE OF RAIN TO PORTIONS OF OUR AREA. ONCE AGAIN...FOR THE
DAY SATURDAY THE HIGHEST POPS HAVE BEEN RELEGATED TO OUR SOUTHEAST
WHERE BROAD-SCALE LIFT IS EXPECTED TO BE STRONGEST. PRECIPITATION
MAY LINGER OVER OUR AREA SATURDAY NIGHT INTO SUNDAY AS THE MID
LEVEL TROUGH AXIS FINALLY CLEARS OUT OF THE AREA...BUT AN OVERALL
LACK IN KINEMATIC FORCING SHOULD BRING DRY CONDITIONS TO THE AREA
MONDAY ONWARD AS THE UPPER LEVEL RIDGE BUILDS INTO THE AREA.
INSTABILITY DURING THE FRIDAY THROUGH SUNDAY TIME PERIOD APPEARS
FAIRLY MEAGER PER THE NAM AND OPERATIONAL GFS AND AS RESULT...WILL
LEAVE ANY MENTION OF SEVERE WEATHER OUT OF THE HWO FOR THE
EXTENDED FORECAST PERIOD.

INCREASING CLOUD COVER AND PRECIPITATION WILL LIKELY PRESENT
FAIRLY TIGHT DIURNALS FRIDAY AND SATURDAY...WITH GUIDANCE NOW
PRESENTING AFTERNOON HIGHS IN THE LOW TO MID 80S ACROSS MUCH OF
THE CWA BOTH DAYS. IN FACT...AN EASTERLY COMPONENT TO THE LOW
LEVEL WIND FIELD ON SATURDAY...WORKING IN CONCERT WITH INCREASED
CLOUD COVER AND POSSIBLE PRECIPITATION...MAY KEEP DIURNALS UNDER
20 DEGREES WHICH WOULD ONLY PROVIDE HIGHS IN THE 70S FOR PORTIONS
OF THE CWA. A WARMING TREND IS THEN EXPECTED TO FINISH OUT THE
LONG TERM FORECAST PERIOD AS THE AFOREMENTIONED UPPER LEVEL
RIDGING BUILDS INTO THE AREA.

.GID WATCHES/WARNINGS/ADVISORIES...

NE...NONE.
KS...NONE.

AVIATION/UPDATE...ROSSI
SHORT TERM...EWALD
LONG TERM...BRYANT

AREA FORECAST DISCUSSION

NWS HASTINGS NE

743 PM CDT WED AUG 22 2012

.UPDATE...WENT AHEAD AND CANCELLED THE RED FLAG WARNING ABOUT AN
HOUR EARLY AS TEMPERATURES HAVE BEGUN TO FALL AND RELATIVE
HUMIDITIES ARE ON THE RISE. OTHERWISE...MADE A FEW ADDITIONAL
CHANGES TO THE FORECAST PACKAGE TO REFLECT CHANCES FOR PRECIP
OVERNIGHT AS CONVECTION ROLLS OFF THE HIGH PLAINS. FOLLOWED FAIRLY
CLOSELY TO HRRR GUIDANCE...BRINGING A FEW SHOWERS IN THE LATE
EVENING ACROSS THE WESTERN FRINGES OF THE FORECAST AREA...AND
KEEPING VERY SMALL POPS ACROSS THE REMAINDER OF THE AREA DURING
THE OVERNIGHT HOURS. OTHERWISE...MADE NO TWEAKS BEYOND 23/12Z AT
THIS TIME.

.PREV DISCUSSION... /ISSUED 641 PM CDT WED AUG 22 2012/

AVIATION...00Z KGRI TAF...VRF CONDITIONS ARE EXPECTED TO PREVAIL
AT KGRI FOR THE NEXT 24 HOURS. GUSTY SOUTHERLY WINDS AT THE
TERMINAL THIS EVENING ARE EXPECTED TO RAPIDLY DIMINISH AROUND
23/01-23/02Z...WITH WINDS FALLING TO NEAR OR BELOW 12 KTS
OVERNIGHT. WHILE THERE IS A VERY SMALL CHANCE A LIGHT SHOWER OR
TWO MAY REACH THE TERMINAL DURING THE LATE EVENING AND OVERNIGHT
HOURS AS CONVECTION ACROSS THE HIGH PLAINS TRACKS EAST...LATEST
MODEL GUIDANCE IS NOT SUPPORTING THIS AND KEPT ANY MENTION OF A
-TSRA OR VCTS OUT OF TAF. FOR THURSDAY...EXPECT WINDS TO INCREASE
AGAIN AFTER SUNRISE AS LEE TROUGH TO THE WEST RESTRENGTHENS...ONCE
AGAIN GUSTING TO NEAR OR ABOVE 25KTS AFT 23/17Z. OTHERWISE...BEST
CHANCE OF PRECIP LIES JUST BEYOND CURRENT SCOPE OF TAF...WITH A
TSRA OR VCTS POSSIBLE TOMORROW EVENING AS A WEAK UPPER LEVEL
DISTURBANCE APPROACHES THE TERMINAL.

PREV DISCUSSION... /ISSUED 316 PM CDT WED AUG 22 2012/

SHORT TERM...TONIGHT THROUGH THURSDAY AFTERNOON. PRIMARY CONCERN
WILL BE SMALL PRECIPITATION CHANCES OVERNIGHT AND DURING THE DAY
ON THURSDAY.

MODELS SIMILAR IN SOME RESPECTS WITH MOVING THE WAVES NOTED ABOVE
EASTWARD WITH BOTH GFS AND NAM KICKING OUT A MORE SUBTLE SHORTWAVE
AHEAD OF THE SOUTHERN SYSTEM THAT IS SLATED TO PUSH ACROSS SOUTHERN
NEB ON THURSDAY. GFS LOOKS TO HAVE SOME CONVECTIVE FEEDBACK ISSUES
THURS AFTERNOON AS IS DEVELOPS A VORTICITY BULLS EYE ACROSS THE KS
PART OF OUR CWA LATE THURS AFTN INTO THE OVERNIGHT. THIS CAUSES THE
MODEL TO GENERATE WAY TOO MUCH RAINFALL IN THAT AREA. THE OTHER
FEATURE OF NOTE IS A SURFACE TROUGH AND DRY LINE THAT EXTEND JUST
WEST OF OUR CWA BY THURSDAY NOON. POSSIBLE THAT THIS COULD BE AN
AREA WHERE STORMS DEVELOP AND THEN DRIFT EAST ACROSS OUR REGION.
CAPE VALUES IN THE 2000+ J/KG RANGE WITH DEEP LAYER SHEAR PROGGED TO
BE 25-30 KT. IF STORMS DO DEVELOP A FEW STRONG TO SEVERE NOT OUT OF
THE QUESTION. ONE OF THE ISSUES HERE IS WHEN AND WHERE ANY MID LEVEL
SUPPORT WILL BE.

INCREASING CLOUD COVER AND PRECIPITATION WILL LIKELY PRESENT FAIRLY TIGHT
DIURNALS FRIDAY AND SATURDAY...WITH GUIDANCE NOW PRESENTING
AFTERNOON HIGHS IN THE LOW TO MID 80S ACROSS MUCH OF THE CWA BOTH
DAYS. IN FACT...AN EASTERLY COMPONENT TO THE LOW LEVEL WIND FIELD ON
SATURDAY...WORKING IN CONCERT WITH INCREASED CLOUD COVER AND POSSIBLE
PRECIPITATION...MAY KEEP DIURNALS UNDER 20 DEGREES WHICH WOULD ONLY
PROVIDE HIGHS IN THE 70S FOR PORTIONS OF THE CWA. A WARMING TREND
IS THEN EXPECTED TO FINISH OUT THE LONG TERM FORECAST PERIOD AS THE
AFOREMENTIONED UPPER LEVEL RIDGING BUILDS INTO THE AREA.

.GID WATCHES/WARNINGS/ADVISORIES...

NE...NONE.
KS...NONE.

AVIATION/UPDATE...ROSSI
SHORT TERM...EWALD
LONG TERM...BRYANT

AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

629 PM CDT WED AUG 22 2012

.AVIATION...

GUSTY SOUTHERLY WINDS WILL IMPACT MUCH OF WESTERN NEBRASKA
THROUGH THIS EVENING. MAY SEE GUSTS BACK OFF A BIT LATER THIS
EVENING...BUT WITH A TIGHT PRESSURE GRADIENT SHOULD STAY FAIRLY
BREEZY THROUGH AT LEAST 09Z AT KVTN. ALSO OF CONSIDERATION...THE
LOW LEVEL JET WILL PICK UP THIS EVENING...WITH SOUNDINGS
INDICATING WINDS JUST ABOVE THE SURFACE OF 40KTS. THINK WITH
SURFACE WINDS STAYING HIGHER...LOW LEVEL WIND SHEAR IS NOT NEEDED
AT THIS TIME. SCATTERED TO BROKEN CLOUD COVER IS EXPECTED THROUGH
THE PERIOD...HOWEVER CEILINGS WILL REMAIN VFR. ALSO...ISOLATED
NEAR AND WEST OF KVTN FOR MENTION OF VCTS UNTIL 02Z. ACTIVITY WEST
OF KOGA CONTINUES TO DISSIPATE...SO KLBF DRY THOUGH THIS EVENING.
ELEVATED STORMS COULD DEVELOP AFTER 08Z FOR KLBF...WITH A BKN120
DECK MENTION.

.PREV DISCUSSION... /ISSUED 300 PM CDT WED AUG 22 2012/

DISCUSSION...
NO OBVIOUS FOR ISOLATED STORM DEVELOPMENT SHOWING ON RADAR OR VSBY
SATELLITE. WATER VAPOR AND THE RAP MODEL INDICATE A MID LEVEL DISTURBANCE
NEAR KSLC. THIS DISTURBANCE IS PROGGED BY ALL MODELS TO BEGIN
AFFECTING THE FCST AREA THURSDAY AFTERNOON SO RAIN CHANCES THIS
EVENING...ALBEIT ISOLATED...LOOK UNCERTAIN AT THIS TIME. NOTE THAT
THE RAP IS POOLING CONSIDERABLE MOISTURE ACROSS SWRN LATE TONIGHT.
THE COULD RAISE THE PROSPECT OF STRATUS BUT NON IS INDICATED BY 12Z
AT KMCK.

THUS THE FCST TURNS TO THURSDAY AFTERNOON. THE NAM AND GEM BRING
A WEAK COLD FRONT THROUGH THE FCST AREA OVERNIGHT. NEITHER THE GFS
NOR THE ECM SHOW THIS FEATURE. THEY INSTEAD WASH THE FRONT OUT
NEAR THE SOUTH DAKOTA BORDER AND MAINTAIN A BELT OF STRONG
SOUTHWEST WINDS FARTHER WEST DURING THE DAY THURSDAY. BY THIS TIME
THE DISTURBANCE CURRENTLY ACROSS NRN UT SHOULD BE OPERATING ACROSS
KS AND SRN NEB. ALL MODELS SUGGEST A HEAVY RAIN CENTER WILL
DEVELOP THURSDAY NIGHT THROUGH FRIDAY...SOMEWHERE ACROSS KS. THE
NAM WAS THE FARTHEST NORTH PRODUCING 1.8 INCHES NEAR NORTON KS.
THE 12Z GFS INDICATED 11 INCHES OVER KHLC. THE ECM AROUND 2.5 NEAR
KP28 AND THE SREF HAD 1.35 NEAR KGLD. ALL OF THESE SOLNS WERE
BLENDED TOGETHER TO PRODUCE CHC POPS ACROSS SWRN AND SCNTL NEB. BY
FRIDAY MORNING MOST SOLNS SHOW A CLOSE 500 MB LOW FORMING OVER KS
AND IT APPEARS THE MODELS ARE TAKING PIECES OF THE DEEP SWRN U.S.
UPPER LEVEL LOW ACROSS THE ROCKIES AND RECONSOLIDATING IT OVER
KS.

SO THE FCST FOLLOWS THESE SOLNS AND PARTS OF THE FCST AREA WILL BE
ON THE PERIPHERY OF WHAT COULD BECOME A LARGE COMPLEX OF SHOWERS
AND THUNDERSTORMS LATE THURSDAY THROUGH FRIDAY. A POWERFUL NRN
STREAM DISTURBANCE WILL TRACK ALONG THE CANADIAN BORDER FRIDAY
NIGHT AND SATURDAY AND THIS SHOULD OPEN UP THE CLOSED KS LOW AND
SHEAR IT OUT TO THE EAST SOMETIME DURING THE DAY SATURDAY.. A
SIGNIFICANT COLD FRONT WILL SWEEP SOUTH THROUGH THE FCST AREA
SATURDAY PRODUCING HIGHS IN THE 80S WITH DRY CONDITIONS.

SUNDAY THROUGH WEDNESDAY...DRY WEATHER IS EXPECTED. THE DROUGHT
RIDGE WILL GRADUALLY BUILD NORTH TOWARD THE CNTL PLAINS AND
ANOTHER STRONG NORTHERN STREAM LOW WILL BEGIN TRACKING ALONG THE
CANADIAN BORDER. THIS SHOULD SPAWN A HIGH PLAINS LOW PRESSURE
SYSTEM AND DRAW WARM AIR BACK NORTH. TEMPS SHOULD RISE BACK INTO
THE LOW TO MID 90S NEXT WEEK. A COLD FRONT SHOULD MOVE THROUGH
LATE TUESDAY OR WEDNESDAY FOR COOLER HIGHS WEDNESDAY .

TEMPERATURES THURSDAY AND FRIDAY ARE A COMPLEX BLEND OF BIAS
CORRECTED MODEL DATA AND GUIDANCE. THE MODELS ARE FCSTING DEEP
MOISTURE AND STRATUS FRIDAY AND SATURDAY MORNINGS WHICH COULD HAVE
A BIG IMPACT ON HIGH TEMPERATURES.

FIRE WEATHER...

AS FUELS REMAIN VERY DRY...CONDITIONS THROUGH THE REMAINDER OF THIS
AFTERNOON WILL BE CRITICAL OR NEAR CRITICAL ACROSS MUCH OF WESTERN
AND NORTH CENTRAL NEBRASKA WITH RELATIVE HUMIDITY NEAR 20 PERCENT
AND GUSTY WINDS. FOR FIRE ZONE 209...A RED FLAG WARNING WILL
CONTINUE THROUGH 8 PM CDT.

WINDS WILL STAY BREEZY AND CONTINUE TO GUST TO 25 MPH OR HIGHER THIS
EVENING DUE TO A TIGHT PRESSURE GRADIENT AND STRONG WINDS ALOFT
MIXING DOWN TO THE SURFACE. THESE WINDS WILL DIMINISH SLIGHTLY INTO
THURSDAY MORNING...WITH GUSTS ON THURSDAY EXPECTED TO BE LESSER
ACROSS THE DISTRICTS. IN TERMS OF HUMIDITY...COOLING TEMPERATURES
THIS EVENING WILL CAUSE THE AIR TO BECOME MORE HUMID...WHICH WILL
ALLEVIATE THE DISTRICTS FROM THE CRITICAL FIRE WEATHER CONDITIONS.

IN ADDITION...THERE IS POTENTIAL FOR THUNDERSTORMS ALONG AND WEST OF
A LINE FROM OGALLALA TO THEDFORD TO AINSWORTH THIS EVENING. ANY
THUNDERSTORMS WILL HAVE THREATS ERRATIC AND GUSTY WINDS AND DRY
LIGHTNING...AS THE BOUNDARY LAYER IS VERY DRY. BELIEVE ANY STORMS
WILL BE ISOLATED IN NATURE.

.LBF WATCHES/WARNINGS/ADVISORIES...RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ209.

SHORT TERM/EXTENDED...NWS
AVIATION...ROBERG

AREA FORECAST DISCUSSION...UPDATED

NWS NORTH PLATTE NE

412 PM CDT TUE AUG 21 2012

.UPDATE...

.DISCUSSION...
RADAR INDICATES ISOLATED THUNDERSTORMS MAY BE DEVELOPING A BIT
FARTHER NORTH THAN FCST BY THE HRRR. SO A MINOR ADJUSTMENT FOR
ISOLATED EVENING TSTMS HAS BEEN MADE ACROSS FAR SOUTHERN
NEBRASKA.

.PREV DISCUSSION... /ISSUED 332 PM CDT TUE AUG 21 2012/

DISCUSSION...
AN AREA OF WEAK CU IS FORMING ACROSS FAR SW NEB THIS AFTERNOON.
THE HRRR SUGGEST ISOLATED STORM DEVELOPMENT WITH STORM MOTION
SOUTHEAST AND AWAY FROM THE FCST AREA. OTHERWISE NO SIGNIFICANT
WEATHER IS EXPECTED OVERNIGHT. LOW PRESSURE ACROSS THE NRN HIGH
PLAINS AND A WARM FRONT STRETCHING ACROSS NRN NEB SHOULD KEEP MIN
TEMPS WARMER TONIGHT. THE SFC LOW IS EXPECTED TO BEGIN MOVING
SLOWLY SOUTH OVERNIGHT.

ON WEDNESDAY...THE LOW DROPS SOUTH TOWARD SWRN SD AND NW NEB BY
LATE AFTERNOON. MOISTURE ALOFT WILL INCREASE AHEAD OF A WEAK NRN
STREAM DISTURBANCE. THE COMBINATION OF THE DISTURBANCE ACROSS THE
NRN PLAINS...INCREASING MOISTURE ALOFT AND STRONG SFC HEATING
SHOULD PRODUCE ISOLATED LATE AFTERNOON TSTMS. MODEL QPF IS
IGNORING THE VERY DRY AIR BELOW 700 MB AND PRODUCING QPF AS HIGH
AS .66 INCHES. THE NAM INDICATED DELTA T-TD HIGHER THAN 40 DEGREES
YET STILL PRODUCED 2/3 OF AN INCH OF QPF. SO POPS ARE LIMITED TO
THE ISOLATED CATEGORY. K INDICES IN THE MODEL ARE BELOW 40C WHICH
IS GENERALLY THE LIMIT FOR SCATTERED STORM COVERAGE. WE WILL SEE
IF THE MODELS CAN SHOW DEEPER MOISTURE BEFORE RAISING FCST POPS.

IN THE WAKE OF THE DISTURBANCE WEDNESDAY NIGHT...A WEAK COLD FRONT
WILL DROP THROUGH WRN NEB IN THE MORNING ANGLED SW THROUGH KIML AND INTO
A SFC HEAT LOW ACROSS ERN COLO. THE FRONT WILL DRIFT SOUTH AND
EAST THROUGHOUT THE AFTERNOON. SOUTHWEST WINDS BELOW 700 MB WILL HAVE
EVACUATED WHATEVER MOISTURE WAS THERE AND THE DEPARTING UPPER
LEVEL DISTURBANCE WILL DRY OUT THE ATM ALOFT. THUS NO RAIN IS EXPECTED
THURSDAY EXCEPT PERHAPS ACROSS CNTL NEB DEPENDING ON THE LOCATION
OF THE FRONT.

A DEEP UPPER LEVEL DISTURBANCE WILL BE TRACKING THROUGH SRN
ALBERTA AND SRN SASKATCHEWAN FRIDAY. THIS SYSTEM SHOULD DRAW DEEPER
MOISTURE FROM TEXAS NORTH THROUGH WRN NEB DURING THE AFTERNOON AND
SUFFICIENT UPPER LEVEL FORCING SHOULD BE AVAILABLE FOR ISOLATED
STORM DEVELOPMENT FRIDAY AFTERNOON. A BROAD AREA OF STRATUS MAY DEVELOP
FRIDAY MORNING AS MOISTURE LIFTS NORTH. ALL SOLNS EXCEPT THE NAM12
SHOW THIS FORMING.

TEMPERATURES ARE EXPECTED TO RISE INTO THE 90S WEDNESDAY THROUGH
FRIDAY. VERTICAL MIXING PROFILES MAY BE LIMITED AS THE SFC LOW
WILL GENERALLY DROP DUE SOUTH THROUGH THE HIGH PLAINS VS TRACKING
EAST THROUGH SRN SD. SO MAX TEMPS FOLLOW A MIDDLE OF THE ROAD
APPROACH FOR A MIX OF HIGHS IN THE LOWER...MIDDLE AND A FEW UPPER 90S.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY.

DECENT LOW AND MID LEVEL MOISTURE WILL SPREAD NORTH INTO THE AREA
FROM THE SOUTH FRIDAY NIGHT AHEAD OF A DECENT MID LEVEL DISTURBANCE.
850 MB DEW PTS PER THE ECMWF ARE PROGGED TO RISE TO NEAR 16C.
CHANCES FOR RAIN ARE EXPECTED TO INCREASE SATURDAY AS THE
DISTURBANCE MOVES ACROSS THE AREA...BUT RIGHT NOW MODELS INDICATING
THE BEST FOCUS FOR RAINFALL/CONVECTION MAY STAY SOUTH AND EAST OF
THE AREA. SO WON/T GET CARRIED AWAY WITH POPS...AND JUST CONTINUE
THE INHERITED 40 PERCENT CHANCES. SYSTEM MOVES EAST OF THE AREA
SUNDAY...WITH DRY WEATHER EXPECTED THE FIRST OF NEXT WEEK.

TEMPERATURE WISE...NEAR SEASONAL HIGHS IN THE 80S ARTE EXPECTED FOR
THE WEEKEND. BY EARLY NEXT WEEK HIGHS COULD REACH BACK INTO THE
LOWER 90S. LOWS WILL BE QUITE MILD WITH THE INCREASED
MOISTURE...WITH MOST AREAS STAYING IN THE 60S AT NIGHT.

AVIATION...
MOSTLY CLEAR SKIES AND VFR CONDITIONS WILL PREVAIL THE
NEXT 24 HRS ACROSS WESTERN AND NORTH CENTRAL NEB. SFC WINDS WILL BE
SOUTH TO SOUTHEAST AT 5 TO 15 KTS.

FIRE WEATHER...
BREEZY SOUTHERLY WINDS WILL INCREASE WEDNESDAY IN
RESPONSE TO A TIGHTENING PRESSURE GRADIENT ACROSS THE AREA. SOME
INCREASE IN LOW LEVEL MOISTURE IS EXPECTED...AND MINIMUM RELATIVE
HUMIDITY VALUES ARE EXPECTED TO REMAIN ABOVE 20 PERCENT. THE NAM
MODEL MAY BE DRYING OUT THE LOW LEVELS A LITTLE TOO MUCH ACROSS
CENTRAL NEBRASKA BASED ON WHAT IS OCCURRING TODAY...AND WILL FORGO A
FIRE WEATHER WATCH FOR THE THAT AREA AT THIS TIME.

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&

SHORT TERM/EXTENDED...CDC
AVIATION...TAYLOR

AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

332 PM CDT TUE AUG 21 2012

.DISCUSSION...
AN AREA OF WEAK CU IS FORMING ACROSS FAR SW NEB THIS AFTERNOON.
THE HRRR SUGGEST ISOLATED STORM DEVELOPMENT WITH STORM MOTION
SOUTHEAST AND AWAY FROM THE FCST AREA. OTHERWISE NO SIGNIFICANT
WEATHER IS EXPECTED OVERNIGHT. LOW PRESSURE ACROSS THE NRN HIGH
PLAINS AND A WARM FRONT STRETCHING ACROSS NRN NEB SHOULD KEEP MIN
TEMPS WARMER TONIGHT. THE SFC LOW IS EXPECTED TO BEGIN MOVING
SLOWLY SOUTH OVERNIGHT.

ON WEDNESDAY...THE LOW DROP SOUTH ACROSS SWRN SD AND NW NEB BY
LATE AFTERNOON. MOISTURE ALOFT WILL INCREASE AHEAD OF A WEAK NRN
STREAM DISTURBANCE. THE COMBINATION OF THE DISTURBANCE ACROSS THE
NRN PLAINS...INCREASING MOISTURE ALOFT AND STRONG SFC HEATING
SHOULD PRODUCE ISOLATED LATE AFTERNOON TSTMS. MODEL QPF IS
IGNORING THE VERY DRY AIR BELOW 700 MB AND PRODUCING QPF AS HIGH
AS .66 INCHES. THE NAM INDICATED DELTA T-TD HIGHER THAN 40 DEGREES
YET STILL PRODUCED 2/3 OF AN INCH OF QPF. SO POPS ARE LIMITED TO
THE ISOLATED CATEGORY. K INDICES IN THE MODEL ARE BELOW 40C WHICH
IS GENERALLY THE LIMIT FOR SCATTERED STORM COVERAGE. WE WILL SEE
IF THE MODELS CAN SHOW DEEPER MOISTURE BEFORE RAISING FCST POPS.

IN THE WAKE OF THE DISTURBANCE WEDNESDAY NIGHT...A WEAK COLD FRONT
WILL DROP THROUGH WRN NEB IN THE MORNING ANGLED SW THROUGH KIML AND INTO
A SFC HEAT LOW ACROSS ERN COLO. THE FRONT WILL DRIFT SOUTH AND
EAST THROUGHOUT THE AFTERNOON. SOUTHWEST WINDS BELOW 700 MB WILL HAVE
EVACUATED WHATEVER MOISTURE WAS THERE AND THE DEPARTING UPPER
LEVEL DISTURBANCES DRY OUT THE ATM ALOFT. THUS NO RAIN IS EXPECTED
THURSDAY EXCEPT PERHAPS ACROSS CNTL NEB DEPENDING ON THE LOCATION
OF THE FRONT.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY.

.AVIATION...
MOSTLY CLEAR SKIES AND VFR CONDITIONS WILL PREVAIL THE
NEXT 24 HRS ACROSS WESTERN AND NORTH CENTRAL NEB. SFC WINDS WILL BE
SOUTH TO SOUTHEAST AT 5 TO 15 KTS.

.FIRE WEATHER...
BREEZY SOUTHERLY WINDS WILL INCREASE WEDNESDAY IN
RESPONSE TO A TIGHTENING PRESSURE GRADIENT ACROSS THE AREA. SOME
INCREASE IN LOW LEVEL MOISTURE IS EXPECTED...AND MINIMUM RELATIVE
HUMIDITY VALUES ARE EXPECTED TO REMAIN ABOVE 20 PERCENT. THE NAM
MODEL MAY BE DRYING OUT THE LOW LEVELS A LITTLE TOO MUCH ACROSS
CENTRAL NEBRASKA BASED ON WHAT IS OCCURRING TODAY...AND WILL FORGO A
FIRE WEATHER WATCH FOR THE THAT AREA AT THIS TIME.

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&

SHORT TERM/EXTENDED...CDC/TALYOR
AVIATION...TAYLOR

AREA FORECAST DISCUSSION

NWS RALEIGH NC

130 AM EDT TUE AUG 21 2012

.SYNOPSIS...
AN UPPER LEVEL TROUGH PARKED OVER THE MISSISSIPPI VALLEY WILL
CONTINUE TO BRING COOLER AND MORE UNSETTLED WEATHER TO THE AREA
THROUGH THE END OF THE WEAK BEFORE HIGHER PRESSURE MOVES IN FOR THE
WEEKEND.

.NEAR TERM /THROUGH TUESDAY NIGHT/...
AS OF 950 PM MONDAY...

DEEP L/W TROUGH ALOFT CONTINUES TO ALLOW MID/UPPER MOISTURE TO
STREAM INTO THE AREA THIS EVENING... RESULTING IN MOSTLY CLOUDY TO
OVERCAST SKIES. AT THE SURFACE A WEAK SURFACE FRONT/TROUGH CONTINUES
TO LINGER ACROSS COASTAL PORTIONS OF NC EXTENDING SOUTHWESTWARD INTO
THE GULF COAST STATES... WITH A MORE SIGNIFICANT AIR MASS CHANGE
ACROSS THE REGION (AT OUR LATITUDE) REMAINING GENERALLY ALONG AND
WEST OF THE MOUNTAINS. CONVECTION HAS GENERALLY REMAINED TO OUR EAST
INVOF THE WEAK FRONTAL ZONE AND TO OUR WEST WHERE CONVECTION
ORIGINATED OVER THE HIGHER TERRAIN AND HAS MOVED SLOWLY EASTWARD.
HOWEVER... SOME OF THE SHOWERS AND STORMS WHICH ORIGINATED OVER THE
HIGHER TERRAIN ARE NOW MAKING MOVING INTO OUR NORTHWEST PIEDMONT.
EXPECT THIS CONVECTION TO BEGIN TO WANE AS IT CONTINUES TO SLOWLY
MOVE EASTWARD ACROSS THE NORTHWEST PIEDMONT OVER THE NEXT HOUR OR
SO... GIVEN LACK OF OVERALL INSTABILITY (~500 MLCAPE AND AROUND 500
MUCAPE)... WHICH IS GENERALLY SUPPORTED BY HIRES MODELS. DO NOT
EXPECT ANY OF THIS ACTIVITY TO BE SEVERE GIVEN THE LACK OF
INSTABILITY AND CURRENT RADAR TRENDS. EXPECT THE STRONGEST STORMS
(IF ANY) COULD PRODUCE 30-35 MPH WIND GUSTS AND VERY SMALL HAIL.
THUS... HAVE REMOVED MENTION OF SEVERE STORMS FROM THE DAY ONE
SECTION OF THE HWO. HOWEVER... WE MAY SEE SOME SHOWERS AND PERHAPS
ISOLATED STORMS MOVE INTO SOUTHERN/SOUTHEASTERN PORTIONS OF THE AREA
TONIGHT AS ANOTHER IMPULSE ALOFT AND WEAK SURFACE WAVE TRACK ALONG
THE WEAK FRONT/TROUGH (GENERALLY AFTER MIDNIGHT). THIS IS SUPPORTED
BY THE LATEST RAP AND SOMEWHAT BY THE LAST FEW RUNS OF THE HRRR.
THUS... WILL BUMP POPS UP IN THE SOUTHEAST TO CHANCE GENERALLY AFTER
05/06Z OR SO. THINK WE WILL HAVE ENOUGH MID/HIGH LEVEL MOISTURE
ACROSS THE AREA TO SEE TOO MUCH FOG. THUS... WILL JUST MENTION
PATCHY FOG... WITH LOW STRATUS DEVELOPING/MOVING INTO THE AREA
OVERNIGHT. EXPECT OVERNIGHT LOWS TO GENERALLY BE IN THE MID TO UPPER
60S. -BSD

FOR TUESDAY THE CHANCES FOR SEVERE WEATHER FOR TOMORROW AFTERNOON
WILL BE A BIT BETTER WITH MORE INSTABILITY AVAILABLE BUT IT WILL BE
CONFINED TO EASTERN PORTIONS OF THE CWA AND SHOULD STILL BE
ISOLATED. SHEAR WILL STILL BE PLENTIFUL AS THE JET CONTINUES TO MAKE
AN EXIT TO THE NORTHEAST. DURING THE AFTERNOON HOURS A 500 MB VORT
MAX SHOULD MAKE HEADWAY UP THE COAST BUT WHETHER OR NOT THIS FEATURE
PASSES CLOSE ENOUGH TO THE EASTERN PERIPHERY TO HELP SUPPORT
CONVECTION REMAINS TO BE SEEN. SURFACE HIGH PRESSURE TO THE
NORTHWEST WILL START TO WORK INTO THE AREA...POTENTIALLY CONFINING
CONVECTION EVEN FURTHER TO THE EAST DEPENDING ON PROGRESS. WHILE THE
UPPER LEVEL TROUGH WILL STILL BE IN PLACE IT WILL BEGIN TO LIFT OUT
AS THE UPPER JET CONTINUES UP THE EASTERN SEABOARD. MAX TEMPERATURES
TUESDAY WILL BE IN THE LOWER 80S WITH LOWS TUESDAY NIGHT IN THE MID
60S. -ELLIS

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 245 PM MONDAY...

WEDNESDAY AND WEDNESDAY NIGHT:
THE LATEST 12Z MODEL GUIDANCE INDICATES SHORTWAVE ENERGY DIGGING
SOUTHEAST THROUGH THE CENTRAL PLAINS ON TUE...AND INTO THE LOWER MS
RIVER VALLEY/DEEP SOUTH ON WED...PROGRESSING EASTWARD INTO THE
SOUTHEAST STATES WED NIGHT...WITH A LOW-LEVEL TROUGH (OR WEAK
SFC-H85 LOW) DOWNSTREAM OVER THE EASTERN CAROLINAS. A SHEAR AXIS IS
EXPECTED TO EXTEND SW-NE ALONG THE APPALACHIANS IN BOTH WED/WED
NIGHT...PROGRESSING SLOWLY EASTWARD TOWARD THE CENTRAL CAROLINAS/VA.
UNCERTAINTY PERSISTS W/REGARD TO THE EVOLUTION OF UPSTREAM SHORTWAVE
ENERGY...LENDING UNCERTAINTY TO THE LOW-LEVEL PATTERN OVER THE
CAROLINAS WED/WED NIGHT. AS A RESULT...A FAIR AMOUNT OF UNCERTAINTY
IS PRESENT WITH TEMPERATURES...CLOUD COVER AND PRECIPITATION
CHANCES...ESPECIALLY DURING THE DAY WED. HOWEVER...MODEL GUIDANCE IS
IN RELATIVELY GOOD AGREEMENT ON THE OVERALL PATTERN...WHICH WOULD
SUGGEST MORE CLOUD COVER...COOLER TEMPERATURES AND BETTER CHANCES
FOR SHOWER ACTIVITY IN EASTERN PORTIONS OF THE AREA. WILL INDICATE
PRECIP CHANCES RANGING FROM 20-40% ON WED (HIGHEST EAST)...WITH
HIGHS IN THE MID 80S WEST TO NEAR 80F EAST. FOR WED NIGHT...MODEL
GUIDANCE INDICATES THE AFOREMENTIONED SHEAR AXIS SLOWLY PROGRESSING
EASTWARD TOWARD THE CENTRAL CAROLINAS...WITH THE MORE POTENT
SHORTWAVE ENERGY OVER THE SOUTHEAST STATES DEAMPLIFYING AS IT
PROGRESSES TOWARD THE SOUTHEAST COAST. WILL INDICATE 20-30% CHANCES
THROUGH MIDNIGHT (HIGHEST EAST)...WITH 20% IN THE COASTAL PLAIN
THROUGH SUNRISE THU...DRY ELSEWHERE. LOWS THU MORNING EXPECTED TO
RANGE FROM THE LOWER 60S (WEST) TO MID/UPPER 60S (EAST). -VINCENT

.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...

THE LATEST LONG RANGE MODEL GUIDANCE INDICATES A CHANGE IN THE
SYNOPTIC PATTERN OVER THE REGION THIS WEEKEND THROUGH EARLY NEXT
WEEK...WITH TROUGHING OVER THE EASTERN CONUS GIVING WAY TO A
STRENGTHENING UPPER LEVEL RIDGE OVER THE EAST COAST...AND
UNSEASONABLY STRONG SURFACE HIGH PRESSURE EXTENDING SOUTHWARD FROM
NEW ENGLAND INTO THE MID-ATLANTIC AND CAROLINAS. THE PRIMARY
UNCERTAINTY W/REGARD TO THE EXTENDED FORECAST APPEARS TO REVOLVE
AROUND THE EVOLUTION OF A POTENTIAL TROPICAL SYSTEM LATE IN THE
EXTENDED PERIOD (EARLY NEXT WEEK). AT THIS POINT...EXPECT NEAR
NORMAL TEMPERATURES AND PRECIP CHANCES ON THU-FRI...FOLLOWED BY NEAR
NORMAL TEMPERATURES AND BELOW NORMAL PRECIP CHANCES OVER THE
WEEKEND. AS MENTIONED ABOVE...UNCERTAINTY INCREASES CONSIDERABLY BY
EARLY NEXT WEEK...AND AT THIS TIME WILL INDICATE CLIMATOLOGICAL
CONDITIONS ON MONDAY. -VINCENT

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 130 AM TUESDAY...

MOST SITES ARE REPORTING EITHER VFR CONDITIONS OF MVFR VSBYS EARLY
THIS MORNING...WITH SOME PATCHY RAIN MOVING FROM SC INTO
SOUTHEASTERN NC. WITH WIDESPREAD MID AND HIGH CLOUDS OVER THE AREA
AND LITTLE RAIN...VSBYS SHOULD HOLD ABOVE 3SM FOR MOST
SITES...THOUGH A PERIOD OF LIFR VSBYS IS POSSIBLY BY 12Z. ONE AREA
OF CONCERN IS THE WESTERN PIEDMONT WHERE THE BACK EDGE OF THE
MID/HIGH CLOUDS IS APPROACHING KINT AND KGSO. IF SKIES CAN CLEAR OFF
OVER THE TRIAD...THEN IFR/LIFR VSBYS ARE POSSIBLE.

SCATTERED SHOWERS AND STORMS ARE EXPECTED TO DEVELOP THIS
AFTERNOON...THOUGH THERE IS SOME UNCERTAINTY REGARDING THE COVERAGE
OVER CENTRAL NC AS THE AXIS OF BETTER DEEP MOISTURE HAS SHIFTED
FURTHER EAST TO THE COAST. AN UPPER LEVEL DISTURBANCE APPROACHING
FROM THE WEST LATER THIS AFTERNOON AND EVENING SHOULD HELP KICK OFF
SOME CONVECTION OVER WESTERN NC BY 00Z.

OUTLOOK...
WHILE THERE REMAINS A CHANCE OF SHOWERS AND STORMS
WEDNESDAY AFTERNOON...A GENERAL IMPROVEMENT IN AVIATION CONDITIONS
IS EXPECTED THROUGH THE END OF THE WEEK AS THE UPPER LEVEL TROUGH
OVER THE REGION WEAKENS.

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

SYNOPSIS...ELLIS
NEAR TERM...BSD/ELLIS
SHORT TERM...VINCENT
LONG TERM...VINCENT
AVIATION...SMITH

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

645 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A RATHER POTENT MID LEVEL SHORT WAVE AND A WEAK SURFACE TROUGH
WILL COMBINE TO PRODUCE A CHANCE OF SHOWERS AND THUNDERSTORMS
TODAY. THEREAFTER...HIGH PRESSURE AT THE SURFACE AND ALOFT WILL
BRING WARM AND DRY WEATHER FOR THE REMAINDER OF THE WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWERS HAVE DEVELOPED FROM CINCINNATI THROUGH LIMA EARLY THIS
MORNING AHEAD OF A RATHER SHARP SHORT WAVE TROUGH. EXPECT SHOWERS
AND A FEW THUNDERSTORMS TO EXPAND EASTWARD INTO THIS AFTERNOON
AIDED BY INCREASING INSTABILITY DUE TO DAYTIME HEATING. THE TROUGH
AND ASSOCIATED MOISTURE WILL BE MOVING EAST OF THE AREA BY LATE
AFTERNOON...WHICH WILL BRING AN END TO THE PRECIPITATION. THE CHANCE
FOR SEVERE THUNDERSTORMS APPEARS LOW DUE TO WEAK INSTABILITY AND
WIND FIELDS ACCOMPANYING THE SHORT WAVE. TEMPERATURES WILL TOP OUT
AROUND 80 THIS AFTERNOON.

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SKIES WILL CLEAR TONIGHT AS THE SHORT WAVE MOVES WELL EAST OF THE
REGION AND HIGH PRESSURE STARTS TO BUILD AT ALL LEVELS OF THE
ATMOSPHERE. THE HIGH WILL BE ANCHORED TO THE EAST THROUGH
THURSDAY...WHILE 500 MB HEIGHTS INCREASE TO ABOVE 5900 METERS.
THIS WILL RESULT IN A PERIOD OF PERSISTENTLY DRY WEATHER...AND
GRADUALLY INCREASING TEMPERATURES. UNDER MOSTLY SUNNY SKIES AND
MODERATE WARM ADVECTION...HIGHS ON WEDNESDAY WILL BE IN THE LOWER
TO MIDDLE 80S...RISING TO THE MIDDLE AND UPPER 80S ON THURSDAY.

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
SLOWLY BUILDING UPPER HEIGHTS ALONG WITH SOUTHERLY FLOW ON THE BACK
SIDE OF A SURFACE HIGH WILL RESULT IN ABOVE NORMAL TEMPERATURES AND
DRY CONDITIONS THROUGH THE PERIOD. THERE IS SOME POSSIBILITY THAT A
WEAK BOUNDARY COULD APPROACH THE NORTHWEST COUNTIES EARLY NEXT WEEK.
BUT CHANCE OF RAIN REMAINS QUITE LOW AT THIS POINT.

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
MID LEVEL S/W ENERGY PUSHING INTO OHIO HAS SET OFF A FEW SHOWERS
WHICH ARE MOVING ACROSS WESTERN OHIO. LATEST HRRR RUN CONTINUES TO
HAVE A HANDLE ON THESE SHOWERS...WHICH ARE EXPECTED TO LIFT NE AND
CONTINUE TO WEAKEN THIS MORNING. MOST OF THIS SHOWER ACTIVITY WILL
MISS THE TAF SITES WITH ONLY MID LEVEL CIGS EARLY.

AS THE ASSOCIATED LOW LEVEL TROUGH AXIS TRACKS EAST THROUGH THE
DAY...EXPECT ISOLATED TO SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT
AS THE AIRMASS DESTABILIZES THROUGH THE AFTERNOON HOURS. EXACT
LOCATION OF ANY INITIATION REMAINS SOMEWHAT UNCERTAIN. HAVE CONTINUED
A MENTION OF VCSH IN ALL TAFS THIS AFTN. HAVE LIMITED THE WEST TO
EARLY AFTN AND LINGERED CHC IN THE EAST THRU 22Z. INSTBY IS
MARGINAL WITH THE BEST THREAT FOR THUNDER OVER THE EAST. DUE TO
LIMITED INSTBY HAVE ONLY THE MENTION OF VCSH AT THIS TIME. WITH
THE PASSAGE OF THE TROF AXIS THE THREAT OF PRECIPITATION WILL END
BY EVENING. DUE TO LIGHT WINDS AND GOOD LO LEVEL MSTR FOG
DEVELOPMENT IS LKLY TONIGHT. HAVE AN MVFR VSBY RESTRICTION
MENTIONED AT ALL TAF SITES.

.OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO
SHORT TERM...CONIGLIO
LONG TERM...
AVIATION...AR

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

426 AM EDT TUE AUG 21 2012

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
MID LEVEL S/W ENERGY PUSHING ACROSS INDIANA SET OFF A FEW SHOWERS
ALONG THE INDIANA/OHIO BORDER. LATEST HRRR RUN APPEARS TO HAVE A
HANDLE ON THESE SHOWERS...WHICH ARE EXPECTED TO LIFT NE AND
CONTINUE TO WEAKEN EARLY THIS MORNING. A BRIEF SHOWER WILL BE PSBL
EARLY BUT CONDITIONS ARE EXPECTED TO REMAIN VFR. HAVE HANDLED THIS
WITH A MENTION OF VCSH. EXPECT MID LEVEL CIGS WHICH WILL ACT TO
MITIGATE FOG FORMATION. IF WE END UP WITH MORE BREAKS THAN
NOT...SOME MVFR BR WILL BE POSSIBLE...ESPECIALLY AT THE MORE
FAVORABLE KLUK AND POSSIBLY KILN.

AS THE ASSOCIATED LOW LEVEL TROUGH AXIS TRACKS EAST THROUGH THE
DAY...EXPECT ISOLATED TO SCATTERED SHOWER DEVELOPMENT AS THE AIRMASS
DESTABILIZES THROUGH THE AFTERNOON HOURS. EXACT LOCATION OF ANY
INITIATION REMAINS SOMEWHAT UNCERTAIN. HAVE CONTINUED A MENTION OF
VCSH IN ALL TAFS THIS AFTN. WITH THE PASSAGE OF THE TROF AXIS THE
THREAT OF PRECIPITATION WILL END BY EVENING.

.OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO
SHORT TERM...CONIGLIO
LONG TERM...
AVIATION...AR

AREA FORECAST DISCUSSION

NWS WILMINGTON OH

211 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A COUPLE OF UPPER LEVEL DISTURBANCES WILL MOVE THROUGH THE
FORECAST AREA THROUGH TUESDAY EVENING KEEPING PRECIPITATION
CHANCES IN THE FORECAST ACROSS THE REGION. HIGH PRESSURE WILL THEN
MOVE INTO THE AREA FOR THE REMAINDER OF THE WEEK.

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A MID LEVEL SHORT WAVE IS PROGRESSING SLOWLY EAST ACROSS THE
REGION THIS EVENING. THIS IS HELPING TO MAINTAIN SOME SHOWER AND
THUNDERSTORM ACTIVITY ACROSS PARTS OF INDIANA AND INTO NORTHWEST
OHIO. THIS ACTIVITY HAS SHOWN A GRADUAL WEAKENING TREND AND WOULD
EXPECT THAT TO CONTINUE AS IT PUSHES EAST INTO OUR WESTERN AREA
THROUGH LATE EVENING. WE PRETTY MUCH LOSE ALL INSTABILITY BY 06Z
SO WILL JUST HANG ON TO A SLIGHT CHANCE OF SHOWERS ACROSS
PRIMARILY THE WEST THROUGH THE REMAINDER OF THE OVERNIGHT HOURS. AT
THE MOMENT...SKIES HAVE GENERALLY CLEARED OFF ACROSS OUR FA BUT DO
EXPECT TO SEE AT LEAST A PARTIAL INCREASE IN CLOUDS THROUGH THE
OVERNIGHT HOURS AS SHORT WAVE MOVES IN. WILL STICK WITH LOWS IN
THE MID 50S...BUT THIS COULD BE ON THE COOL SIDE IF WE END UP WITH
ENOUGH CLOUDS.

.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
ANOTHER UPPER LEVEL DISTURBANCE WILL WORK THROUGH THE FA ON
TUESDAY. SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
DURING THE DAY AS THIS FEATURE MOVES THROUGH THE REGION. A FEW OF
THE STORMS MAY PRODUCE SOME HAIL ON TUESDAY. WITH ADDITIONAL
CLOUD COVER AND PRECIPITATION ACROSS THE FA ON TUESDAY HIGH
TEMPERATURES WILL BE LIMITED TO THE MIDDLE 70S TO AROUND 80.

PRECIPITATION WILL TAPER OFF BY THE EVENING HOURS ON TUESDAY AND
HIGH PRESSURE WILL WORK INTO THE FA FOR THE REMAINDER OF THE SHORT
TERM TIME FRAME. TEMPERATURES WILL BE SLIGHTLY WARMER ON WEDNESDAY
WITH MORE SUNSHINE ACROSS THE AREA. HIGHS ON WEDNESDAY WILL REACH
UP INTO THE LOWER 80S.

.LONG TERM /THURSDAY THROUGH MONDAY/...
SLOWLY BUILDING UPPER HEIGHTS ALONG WITH SOUTHERLY FLOW ON THE BACK
SIDE OF A SURFACE HIGH WILL RESULT IN ABOVE NORMAL TEMPERATURES AND
DRY CONDITIONS THROUGH THE PERIOD. THERE IS SOME POSSIBILITY THAT A
WEAK BOUNDARY COULD APPROACH THE NORTHWEST COUNTIES EARLY NEXT WEEK.
BUT CHANCE OF RAIN REMAINS QUITE LOW AT THIS POINT.

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
MID LEVEL S/W ENERGY PUSHING ACROSS INDIANA SET OFF A FEW SHOWERS
ALONG THE INDIANA/OHIO BORDER. LATEST HRRR RUN APPEARS TO HAVE A
HANDLE ON THESE SHOWERS...WHICH ARE EXPECTED TO LIFT NE AND
CONTINUE TO WEAKEN EARLY THIS MORNING. A BRIEF SHOWER WILL BE PSBL
EARLY BUT CONDITIONS ARE EXPECTED TO REMAIN VFR. HAVE HANDLED THIS
WITH A MENTION OF VCSH. EXPECT MID LEVEL CIGS WHICH WILL ACT TO
MITIGATE FOG FORMATION. IF WE END UP WITH MORE BREAKS THAN
NOT...SOME MVFR BR WILL BE POSSIBLE...ESPECIALLY AT THE MORE
FAVORABLE KLUK AND POSSIBLY KILN.

.OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

$$
SYNOPSIS...NOVAK
NEAR TERM...JGL
SHORT TERM...NOVAK
LONG TERM...
AVIATION...AR

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

148 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A LARGE UPPER LEVEL TROUGH CARVED OUT OVER THE EASTERN HALF OF THE
U.S. WILL GRADUALLY WEAKEN INTO THE SECOND HALF OF THE WEEK. HIGH
PRESSURE SHOULD BECOME THE MAIN WEATHER FEATURE BY THE END OF THE
WEEK.

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
LAST REMAINING VESTIGES OF EARLIER CONVECTION FOCUSED ALONG
SHORTWAVE TRACKING ACROSS SOUTH CENTRAL MOUNTAINS NOW PETERING OUT
OVER FRANKLIN AND ADAMS COUNTIES...AND WILL BY GONE BY 06Z.

FAVORABLE RADIATIONAL COOLING AND SFC RH/S NR 100 PCT WILL RESULT
IN WIDESPREAD AND LOCALLY DENSE VALLEY FOG EARLY THIS MORNING.
USED A BLEND OF MET AND RUC DATA FOR OVERNIGHT LOWS...WHICH SHOULD
RANGE FROM THE U40S NW MTNS TO M/U50S ACROSS THE LOWER SUSQ
VALLEY.

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
FOG SHOULD BURN OFF TO MSUNNY SKIES BY LATE AM. HOWEVER...DIURNAL
HEATING COMBINED WITH APPROACH OF UPPER LVL TROF SHOULD YIELD
INCREASING CU AND SCT SHRA/TSRA BY AFTN. PWAT VALUES ARE LOWER
THAN MONDAY...SO COVERAGE OF PRECIP SHOULD BE LESS WIDESPREAD.
ELEVATED TERRAIN AND PROXIMITY TO UPPER TROF WILL FAVOR THE
WESTERN AND CENTRAL MTNS FOR HIGHER /CHC/ POPS...WHILE ONLY WIDELY
SCT /SCHC/ POPS EXPECTED ACROSS THE EASTERN COUNTIES. MORE
SUNSHINE WILL RESULT IN A SLIGHTLY WARMER DAY THAN TODAY...WITH
MDL 8H TEMPS SUPPORTIVE OF HIGHS FROM THE L/M70S OVR THE
ALLEGHENIES...TO ARND 80F OVR THE SUSQ VALLEY.

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
THE NORTHEAST U.S. WILL REMAIN IN AN UPPER TROUGH THROUGH LATE
WEEK. HOWEVER...SURFACE HIGH PRESSURE WILL INFILTRATE THE REGION
DURING THE DAY WEDNESDAY. LEFT AN ISOLATED THREAT FOR A
THUNDERSTORM OVER THE EASTER CWA WEDNESDAY AFTERNOON BUT A
MAJORITY OF THE FORECAST AREA WILL SEE DRY WEATHER.

THE UPPER TROUGH FILLS AND WE MOVE TO A MORE ZONAL FLOW ON
THURSDAY. WITH SURFACE HIGH PRESSURE...TEMPERATURES WILL RISE TO
SLIGHTLY ABOVE SEASONAL AVERAGES.

A SLIGHTLY MUDDIED PICTURE SHOWN BY THE EXTENDED MODELS WITH A
FEW UPPER LEVEL RIPPLES MOVE THROUGH THE REGION AS A 500 MB
HEIGHTS REMAIN HIGH OVER THE SOUTHWEST U.S. TIMING OF ANY AREAS OF
PRECIP IS DIFFICULT THIS FAR OUT SO LEFT A MORE OPTIMISTIC OUTLOOK
UNTIL SOMETHING GROWS HORNS.

.AVIATION /05Z TUESDAY THROUGH SATURDAY/...
FAVORABLE RADIATIONAL COOLING AND SFC RH/S NR 100 PCT WILL RESULT
IN WDSPRD VALLEY FOG EARLY THIS MORNING. EXPECT CIGS AND VSBYS TO
DETERIORATE FROM MVFR TO IFR WITH LCL CONDS AOB AIRFIELD MINS PSBL
AROUND DAYBREAK. FOG WILL BURN OFF BY 13-14Z WITH VFR CONDS
PREVAILING FM MID MORNING THRU THE AFTN. UPPER-AIR DISTURBANCE
MOVG EWD FM THE OH VLY COMBINED WITH DIURNAL INSTABILITY WILL
SUPPORT WDLY SCT SHOWERS AND TSTMS DURING THE AFTN. CONVECTION
WILL DISSIPATE WITH THE LOSS OF HEATING WITH CLR SKIES AND MORE
VALLEY FOG TONIGHT INTO EARLY WEDNESDAY.

OUTLOOK...
THU-SAT...MAINLY VFR.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...STEINBUGL
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...DANGELO/FITZGERALD
LONG TERM...TYBURSKI
AVIATION...STEINBUGL

AREA FORECAST DISCUSSION

NWS STATE COLLEGE PA

1224 AM EDT TUE AUG 21 2012

.SYNOPSIS...
A LARGE UPPER LEVEL TROUGH OVER THE EASTERN HALF OF THE U.S. WILL
DOMINATE THE REGIONAL WEATHER PATTERN THROUGH WEDNESDAY.
DISTURBANCES ALOFT WILL ROTATE AROUND THE UPPER LEVEL TROUGH AND
KEEP SHOWERS AND THUNDERSTORMS IN THE FORECAST EARLY THIS WEEK.

CLEARING SKIES...A LGT WIND AND WET GROUND ALREADY RESULTING IN
PATCHY FOG AT 0230Z AND EXPECT IT TO BECOME WIDESPREAD AND LOCALLY
DENSE LATE TONIGHT. GFS EXPERIENCING KNOWN ISSUE OF LOW LVL TEMPS
BEING TOO COOL. THUS...HAVE USED A BLEND OF MET AND RUC DATA FOR
OVERNIGHT LOWS...WHICH SHOULD RANGE FROM THE U40S NW MTNS...TO
M/U50S ACROSS THE LOWER SUSQ VALLEY.

THE UPPER TROUGH FILLS AND WE MOVE TO A MORE ZONAL FLOW ON
THURSDAY. WITH SURFACE HIGH PRESSURE...TEMPERATURES WILL RISE TO
SLIGHTLY ABOVE SEASONAL AVERAGES.

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
MINOR ADJUSTMENTS TO 03Z TAFS.

SKIES STARTING TO CLEAR TO THE WEST...SO STILL EXPECT FOG
TO FORM...PERHAPS NOT QUITE AS FAST AS I HAD IN THE 00Z
TAFS.

SHOWERS AND STORMS JUST ABOUT GONE NOW.

EARLIER DISCUSSION BELOW.

MAIN ISSUE WILL BE DENSE FOG LATE...IFR AND LIFR CONDITIONS
LIKELY.

EXPECT THINGS TO IMPROVE BY MID MORNING ACROSS MOST OF THE
AREA ON TUE. LOWER CHC FOR SHOWERS AND STORMS ON TUE THAN
TODAY.

HOWEVER...SOME CHC FOR SHOWERS AND STORMS TUESDAY NIGHT INTO
WED...AS ANOTHER UPPER LVL SYSTEM ROTATES AROUND THE DEEP
VORTEX.

ALONG WITH THE CHC OF SHOWERS AND STORMS TUESDAY NIGHT...FOG
WILL LIKELY FORM AGAIN.

IMPROVING CONDITIONS STILL EXPECTED LATER IN THE WEEK...AS THE
UPPER LVL FLOW BECOMES MORE ZONAL...THAT IS WEST TO EAST...FOR
A CHANGE...AND TEMPS WARM SOME.

OUTLOOK...
THU-SAT...MAINLY VFR.

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

$$
SYNOPSIS...CERU/STEINBUGL
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...DANGELO/FITZGERALD
LONG TERM...TYBURSKI
AVIATION...MARTIN

AREA FORECAST DISCUSSION...UPDATED

NWS AMARILLO TX

1042 PM CDT WED AUG 22 2012

.UPDATE...
HAVE TRIMMED POPS BACK ACROSS THE WESTERN ZONES TONIGHT AS AREA OF
THUNDERSTORMS CONTINUE TO WEAKEN AS THEY APPROACH THE TX BORDER.
HOWEVER WILL HOLD ONTO SLIGHT CHANCE POPS OVERNIGHT ACROSS THE
FORECAST AREA AS A LOW LEVEL JET SETS UP ACROSS THE SOUTHERN PLAINS.
REMAINDER OF THE FORECAST IS IN GOOD SHAPE WITH ONLY MINOR
ADJUSTMENTS TO SKY GRIDS NEEDED. UPDATED FORECASTS HAVE BEEN SENT.

CLK

.PREV DISCUSSION... /ISSUED 630 PM CDT WED AUG 22 2012/

AVIATION...
AN UPPER RIDGE WILL PREVAIL ACROSS THE THREE TAF SITES TONIGHT AND
EARLY THURSDAY BEFORE AN UPPER TROUGH APPROACHES FROM THE WEST. VFR
CONDITIONS WILL PREVAIL THROUGH THE TAF FORECAST PERIOD. SOME SHOWERS
MAY AFFECT THE DALHART TAF SITE THIS EVENING...BETWEEN 00Z AND 04Z
THURSDAY...HOWEVER CONFIDENCE LOW. SOUTHEAST TO SOUTH WINDS 10 TO 20
KNOTS WILL DIMINISH TO AROUND 5 TO 15 KNOTS AFTER 02Z THURSDAY...AND
THEN INCREASE AFTER 14Z THURSDAY TO AROUND 15 TO 25 KNOTS WITH HIGHER
GUSTS.

SCHNEIDER

PREV DISCUSSION... /ISSUED 321 PM CDT WED AUG 22 2012/

DISCUSSION...
ALREADY SEEING A TRANSITION FROM NORTHWESTERLY FLOW ALOFT TO MORE
WESTERLY FLOW ALOFT IN RESPONSE TO THE APPROACHING CUTOFF LOW
CURRENTLY IN SOUTHERLY CA.

FOR TONIGHT...STORMS FROM THE HIGHER TERRAIN OF NM AND CO WILL
QUICKLY MOVE INTO THE NORTHWESTERN PANHANDLES. THE RAP IS SHOWING
THIS AREA WITH SLIGHTLY HIGHER CAPE VALUES...NEAR 2000 J/KG...AND
MODEST SHEAR VALUES NEAR 30 KT. HOWEVER...THE SEVERE THREAT SHOULD
NOT LAST LONG AS MODEL SOUNDINGS SHOW ONLY ELEVATED INSTABILITY BY
03Z.

TOMORROW AND TOMORROW NIGHT...WILL PROBABLY BE THE BEST CHANCE FOR A
WIDESPREAD RAIN EVENT...ESPECIALLY TOMORROW NIGHT...WITH VORTICITY
ADVECTION AHEAD OF THE MAIN UPPER LEVEL TROUGH. THE BIGGER CONCERN
HOWEVER WILL BE THE POTENTIAL FOR HEAVY RAIN LEADING TO LOCALIZED
FLASH FLOODING...AS PRECIPITABLE WATER VALUES COULD BE ABOVE 1.5
INCHES AND MEAN STORM MOTIONS COULD BE BELOW 20 KT.

FRIDAY THROUGH SUNDAY...SOME CHANCES FOR THUNDERSTORMS CONTINUE
THROUGH THIS PERIOD. HOWEVER...THERE IS UNCERTAINTY IN THE TRACK OF
THE CENTER OF THE UPPER LEVEL LOW. IF THE LOW GOES JUST SOUTH OF THE
TX PANHANDLE AS THE GFS SHOWS...THERE SHOULD BE A RELATIVELY GOOD
CHANCE FOR RAIN THROUGH THE WEEKEND. HOWEVER...ANY DEVIATION TO THE
NORTH...LIKE THE ECMWF SHOWING THE LOW LIFTING NE ACROSS THE TX
PANHANDLE ON SAT...COULD MEAN THE REGION WOULD BE IN THE PRIME
LOCATION FOR THE DRY SLOT...AND THUS HAVE FEW IF ANY CHANCES FOR
STORMS. LIKELY THIS UNCERTAINTY WILL REMAIN FOR THE NEXT FEW MODEL
RUNS AS THE PATH OF THIS LOW IS SOMEWHAT DEPENDENT ON THE EVOLUTION
OF A SECOND UPPER LEVEL TROUGH THAT SHOULD MOVE ACROSS THE NORTHERN
TIER OF THE U.S. AT THE SAME TIME...BUT HAS NOT YET BEEN WELL SAMPLED
BY THE UPPER AIR NETWORK.

MONDAY THROUGH WEDNESDAY...A RIDGE IS EXPECTED TO BUILD OVER THE HIGH
PLAINS...MINIMIZING THE CHANCE FOR RAIN AND BRINGING A WARMING TREND
AT LEAST TO START THE WEEK.

JOHNSON

FIRE WEATHER...
RELATIVELY HIGH ATMOSPHERIC MOISTURE...AND CONTINUED RAIN CHANCES
SHOULD PRECLUDE ANY ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS FOR
THE NEXT SEVERAL DAYS.

JOHNSON

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

11/05

AREA FORECAST DISCUSSION...UPDATED

NWS SAN ANGELO TX

944 PM CDT WED AUG 22 2012

.DISCUSSION...
HAVE UPDATED THE FORECAST TO REMOVE POPS/WX FOR THE REST OF THE
EVENING AS THE ISOLATED SHOWERS TO OUR SOUTH HAVE DISSIPATED WITH
THE LOSS OF DAYTIME HEATING. THERE ARE FEW SHOWERS TO OUR WEST IN
THE PERMIAN BASIN ASSOCIATED WITH WEAK UPPER LEVEL SHORTWAVE
ENERGY. HOWEVER...THESE SHOWERS HAVE BEEN FORMING AND WEAKENING
RATHER QUICKLY AS THEY MOVE EAST...AND WE EXPECT THAT TREND TO
CONTINUE...PREVENTING THEM FROM MAKING IT INTO OUR CWA. NO OTHER
SIGNIFICANT CHANGES WERE NEEDED.

.PREV DISCUSSION... /ISSUED 607 PM CDT WED AUG 22 2012/

DISCUSSION...
SEE 00Z AVIATION DISCUSSION BELOW.

AVIATION...
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TERMINALS THE NEXT 24
HOURS. LCL MVFR CIGS MAY DEVELOP ACROSS THE NORTHWEST HILL COUNTRY
AND HEARTLAND LATE TONIGHT AND THURSDAY MORNING. HOWEVER...WILL
KEEP VFR CONDITIONS GOING AT THE KBBD AND KJCT TAF SITES FOR NOW.
WINDS WILL BE MAINLY SOUTHEAST AT 5 TO 15 KNOTS.

PREV DISCUSSION... /ISSUED 314 PM CDT WED AUG 22 2012/

SHORT TERM...
EARLIER SHOWERS AND STORMS ACROSS THE BIG COUNTRY HAVE NOW
DISSIPATED FOR THE MOMENT. HOWEVER...CU FIELD HAS STARTED TO DEVELOP
ONCE AGAIN...AND THE VARIOUS WRF MODELS AND THE HRRR ALL SHOW SOME
VARYING DEGREE OF CONVECTION POPPING UP ACROSS WEST CENTRAL TEXAS
FOR A FEW HOURS LATE THIS AFTERNOON AND INTO THE EVENING. WILL
INCLUDE A MENTION OF ISOLATED STORMS FOR THE FIRST PERIOD.

OTHERWISE...FAIRLY QUIET PATTERN FOR THE NEXT 36 HOURS. LEE TROUGH
BECOMES BETTER ESTABLISHED ACROSS THE EASTERN NEW MEXICO AND WEST
TEXAS...WITH SOUTHERLY WINDS INCREASING AHEAD OF IT. MORE HIGH
CLOUDS ON THURSDAY......BUT NOT ENOUGH TO HAVE A REALLY SIGNIFICANT
EFFECT ON TEMPERATURES.

LONG TERM...
A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS IS FORECAST FOR PARTS
OF THE AREA DURING THE FIRST PART OF THE EXTENDED FORECAST. AN UPPER
LEVEL HIGH WILL BEGIN TO SHIFT SOUTH INTO MEXICO THURSDAY...WHILE AN
UPPER LEVEL TROUGH APPROACHES FROM THE WEST. AT THE SAME TIME A LEE
TROUGH WILL DEVELOP OVER THE TEXAS PANHANDLE...RESULTING IN
INCREASING SOUTH TO SOUTHEAST WINDS. SHOWERS AND THUNDERSTORMS MAY
DEVELOP OVER PARTS OF WEST TEXAS BY LATE AFTERNOON/EARLY EVENING
THURSDAY...WHERE BETTER SURFACE CONVERGENCE IS EXPECTED. A FEW OF
THESE STORMS MAY DRIFT INTO PARTS OF OUR WESTERN COUNTIES...SO HAVE
INCLUDED SLIGHT CHANCE POPS AFTER 00Z FRIDAY.

MODELS ARE HINTING AT A COUPLE OF SHORTWAVE TROUGHS MOVING ACROSS
NORTH TEXAS. THE FIRST IS WEAKER AND IS FORECAST TO TREK ACROSS THE
PANHANDLE EARLY FRIDAY MORNING. AT THIS TIME...BELIEVE THE MAJORITY
OF PRECIPITATION WILL REMAIN NORTH OF OUR AREA...BUT KEPT SLIGHT
CHANCE POPS OVER THE NORTHERN BIG COUNTRY. THE NEXT...MORE
POTENT...UPPER LEVEL SHORTWAVE TROUGH WILL APPROACH FRIDAY THEN MOVE
ACROSS NORTH TEXAS AND OKLAHOMA SATURDAY. ONCE AGAIN...ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE...WITH THE
FAVORED AREAS BEING OUR NORTHERN AND WESTERN COUNTIES. I KEPT SLIGHT
CHANCE POPS IN FOR FRIDAY AND INTRODUCED SLIGHT CHANCE POPS ON
SATURDAY FOR THE WESTERN HALF OF THE REGION. BEYOND
SATURDAY...MODELS ARE HINTING AT A WEAK COLD FRONT MOVING INTO THE
TEXAS PANHANDLE SUNDAY...WITH SCATTERED SHOWERS AND THUNDERSTORMS
DEVELOPING JUST NORTH OF OUR AREA. FOR NOW...I HAVE LEFT THE
FORECAST DRY BEYOND SATURDAY...BUT FUTURE SHIFTS MAY NEED TO
INTRODUCE POPS. HIGH TEMPERATURES THROUGH THE EXTENDED WILL BE NEAR
TO SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD...GENERALLY IN THE MID
90S.

DANIELS

.PRELIMINARY POINT TEMPS/POPS...
ABILENE 71 94 73 93 74 / 10 10 10 20 20
SAN ANGELO 71 95 73 95 75 / 10 10 10 20 20
JUNCTION 71 93 72 94 74 / 10 10 10 10 20

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION...UPDATED

NWS AMARILLO TX

630 PM CDT WED AUG 22 2012

.AVIATION...
AN UPPER RIDGE WILL PREVAIL ACROSS THE THREE TAF SITES TONIGHT AND
EARLY THURSDAY BEFORE AN UPPER TROUGH APPROACHES FROM THE WEST. VFR
CONDITIONS WILL PREVAIL THROUGH THE TAF FORECAST PERIOD. SOME SHOWERS
MAY AFFECT THE DALHART TAF SITE THIS EVENING...BETWEEN 00Z AND 04Z
THURSDAY...HOWEVER CONFIDENCE LOW. SOUTHEAST TO SOUTH WINDS 10 TO 20
KNOTS WILL DIMINISH TO AROUND 5 TO 15 KNOTS AFTER 02Z THURSDAY...AND
THEN INCREASE AFTER 14Z THURSDAY TO AROUND 15 TO 25 KNOTS WITH HIGHER
GUSTS.

SCHNEIDER

.PREV DISCUSSION... /ISSUED 321 PM CDT WED AUG 22 2012/

DISCUSSION...
ALREADY SEEING A TRANSITION FROM NORTHWESTERLY FLOW ALOFT TO MORE
WESTERLY FLOW ALOFT IN RESPONSE TO THE APPROACHING CUTOFF LOW
CURRENTLY IN SOUTHERLY CA.

MONDAY THROUGH WEDNESDAY...A RIDGE IS EXPECTED TO BUILD OVER THE HIGH
PLAINS...MINIMIZING THE CHANCE FOR RAIN AND BRINGING A WARMING TREND
AT LEAST TO START THE WEEK.

JOHNSON

FIRE WEATHER...
RELATIVELY HIGH ATMOSPHERIC MOISTURE...AND CONTINUED RAIN CHANCES
SHOULD PRECLUDE ANY ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS FOR
THE NEXT SEVERAL DAYS.

JOHNSON

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

11/05

AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

607 PM CDT WED AUG 22 2012

.DISCUSSION...
SEE 00Z AVIATION DISCUSSION BELOW.

.AVIATION...
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TERMINALS THE NEXT 24
HOURS. LCL MVFR CIGS MAY DEVELOP ACROSS THE NORTHWEST HILL COUNTRY
AND HEARTLAND LATE TONIGHT AND THURSDAY MORNING. HOWEVER...WILL
KEEP VFR CONDITIONS GOING AT THE KBBD AND KJCT TAF SITES FOR NOW.
WINDS WILL BE MAINLY SOUTHEAST AT 5 TO 15 KNOTS.

.PREV DISCUSSION... /ISSUED 314 PM CDT WED AUG 22 2012/

DANIELS

.PRELIMINARY POINT TEMPS/POPS...
ABILENE 69 94 73 93 74 / 10 10 10 20 20
SAN ANGELO 68 95 73 95 75 / 10 10 10 20 20
JUNCTION 67 93 72 94 74 / 20 10 10 10 20

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS GREEN BAY WI

1049 PM CDT WED AUG 22 2012

UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND THURSDAY.
MAIN CONCERN FOR THIS PERIOD WILL BE THE CHANCES FOR SHOWERS AND
THUNDERSTORMS TONIGHT AND WEDNESDAY...THEN HIGH TEMPERATURES
WEDNESDAY AFTERNOON.

A CLUSTER OF SHOWERS AND THUNDERSTORMS DEVELOPED ACROSS SOUTHERN
MINNESOTA THIS MORNING AND WAS NOW NEAR THE MINNEAPOLIS AREA. THE
SHOWERS AND STORMS DEVELOPED DUE TO WEAK LOW LEVEL JET...850/700MB
WARM ADVECTION AND STEEP MID LEVEL LAPSE RATES. THESE STORMS PRODUCED
HALF OF A HALF INCH TO HALF DOLLAR SIZE HAIL THIS AFTERNOON. MOST OF
THE BASES OF THESE STORMS WERE AROUND 10 THOUSAND FEET. MODELS DID
NOT HAVE A GOOD HANDLE ON THE DEVELOPMENT OF THIS CLUSTER OF STORMS
AND ALSO DIFFER ON THE EVOLUTION OF THIS CLUSTER OF STORMS AS IT
MOVES EAST INTO WISCONSIN.

THE WRF INDICATES THE 850/700MB WARM ADVECTION WILL MOVE ACROSS
THE AREA TONIGHT WITH THE GREATEST WARM ADVECTION NORTH AND WEST OF
GREEN BAY AND THE FOX VALLEY. DO NOT SEE WHY CONVECTION WOULD END
THIS AFTERNOON AND THIS IS SUPPORTED BY THE LATEST RUC MODEL.
LOOKING AT SOME OF THE MESOSCALE MODELS LIKE THE SPC WRF AND THE
WRF ARW INDICATED ISOLATED TO SCATTERED CONVECTION LATE THIS EVENING
AND OVERNIGHT. HAVE INCREASED CHANCES FOR RAIN AND DID INCLUDE THUNDER
IN THE MORNING UPDATE.

AS FOR THE HWO...WILL MAKE LAST MINUTE DECISION TO ADD HAIL. IT
APPEARS THAT THE RISK FOR LARGE HAIL WILL BE VERY LOW...BUT COULD
NOT RULE IT OUT SINCE LARGE HAIL WAS REPORTED IN MINNESOTA THIS
AFTERNOON.

ON THURSDAY...WARM FRONT WILL CONTINUE TO PUSH NORTH. TEMPERATURES
WERE INCREASED BY A FEW DEGREES...ESPECIALLY ACROSS THE SOUTH DUE
850MB TEMPERATURES AND BASED ON WHAT IS HAPPENING SOUTH OF THE
WARM FRONT TODAY. VERY LOW HUMIDITIES CAN BE EXPECTED...ESPECIALLY
FROM WISCONSIN RAPIDS TO WAUPACA TO WAUTOMA WHERE THEY SHOULD BE
DOWN TO AROUND 25 PERCENT. CONTINUED CHANCES FOR SHOWERS AND
STORMS ON THURSDAY ACROSS THE NORTH. THE 12Z WRF/GFS DID SPIT OUT
A FEW HUNDREDTHS OF AN INCH ACROSS PORTIONS OF CENTRAL AND EASTERN
WISCONSIN. PER COORDINATION WITH MILWAUKEE...THIS DID NOT SEEM
LIKE A FEASIBLE SCENARIO BASED ON MODEL SOUNDINGS.

.LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY...PCPN TRENDS AND
TEMPERATURES ARE THE MAIN FCST CONCERNS.

AN UPPER TROF IS EXPECTED TO MOVE THROUGH THE REGION LATE THURSDAY
NIGHT INTO FRIDAY. BEFORE THE TROF ARRIVES...A WEAK WARM FRONT MAY
STILL BE IN PLACE OVER N WI...SO HAVE POPS CONFINED TO THE NORTHWOODS
DURING THE EVG HOURS. MODELS HAVE TRENDED SLOWER WITH THE ARRIVAL
OF THE UPPER TROF AND ASSOCIATED PCPN...SO WILL ONLY HAVE CHC POPS
FOR PARTS OF NC/C WI LATE THURSDAY NIGHT. THE TROF IS EXPECTED TO
WEAKEN SOMEWHAT AS IT MOVES THROUGH ON FRIDAY...SO SLGT CHC TO
CHC POPS SEEM REASONABLE.

WEAK RIDGING AT THE SFC AND ALOFT SHOULD ALLOW FOR A DRY PERIOD ON
FRIDAY NIGHT. A WEAK INSTABILITY AXIS OVER NC WI ON SATURDAY MAY
ALLOW FOR ISOLD TSTMS...MAINLY DURING THE AFTERNOON.

VERY WARM CONDITIONS WILL PREVAIL OVER THE FORECAST AREA FRIDAY
INTO SATURDAY...WITH HIGH TEMPS IN THE 80S TO LOWER 90S. AS HAS
BEEN THE CASE ALL SUMMER...THE WARMEST TEMPS WILL BE OVER THE
SANDY SOIL AREAS IN CENTRAL WI.

A COLD FRONT IS EXPECTED TO MOVE THROUGH THE AREA LATE SATURDAY
NIGHT INTO SUNDAY EVENING. THE GFS/ECMWF OFFER VERY DIFFERENT
SOLUTIONS WITH REGARD TO PCPN/QPF...WITH THE GFS MUCH WETTER THAN
THE ECMWF. SUSPECT THAT THE ECMWF SOLN IS MORE LIKELY...WITH MOST
OF THE UPPER LEVEL ENERGY PASSING NORTH OF THE RGN. THE GFS MODEL
MAY ALSO BE EXHIBITING SOME PROBLEMS WITH CONVECTIVE FEEDBACK...
LEADING TO ENHANCED S/W ENERGY ENERGY APPROACHING FROM THE CENTRAL
PLAINS. WILL STICK WITH THE MODEL BLEND FOR NOW DURING THIS
PERIOD...WITH MID-RANGE POPS.

AFTER THE FRONT MOVES THROUGH...CANADIAN HIGH PRESSURE WILL BUILD
INTO THE REGION FOR MONDAY INTO TUESDAY...RESULTING MORE SEASONABLE
TEMPERATURES AND DRY CONDITIONS.
&&

.AVIATION...SHOWERS AND THUNDERSTORMS OVER EASTERN MINNESOTA HAVE
FIZZLED THIS EVENING EVEN THOUGH ANALYSIS AND MODELS SUGGEST A
STRENGTHENING LOW LEVEL JET. 00Z MPX SOUNDING INDICATED MOISTURE
WAS WELL ABOVE THE LOW LEVEL JET...SO SHOWER CHANCES HAVE BECOME TOO
SMALL TO INCLUDE IN THE FORECAST. PLENTY OF BKN MID AND HIGH CLOUDS
UPSTREAM HOWEVER...WHICH WILL PASS ACROSS THE REGION OVER THE TAF
PERIOD. SHOULD SEE WIND GUSTS INCREASE THURSDAY AFTERNOON AS A
RESULT OF DEEP MIXING...WHICH WILL THEN TURN INTO LLWS THURSDAY
EVENING.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS GREEN BAY WI

631 PM CDT WED AUG 22 2012

UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE

.SHORT TERM...TONIGHT AND THURSDAY.
MAIN CONCERN FOR THIS PERIOD WILL BE THE CHANCES FOR SHOWERS AND
THUNDERSTORMS TONIGHT AND WEDNESDAY...THEN HIGH TEMPERATURES
WEDNESDAY AFTERNOON.

.LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY...PCPN TRENDS AND
TEMPERATURES ARE THE MAIN FCST CONCERNS.

WEAK RIDGING AT THE SFC AND ALOFT SHOULD ALLOW FOR A DRY PERIOD ON
FRIDAY NIGHT. A WEAK INSTABILITY AXIS OVER NC WI ON SATURDAY MAY
ALLOW FOR ISOLD TSTMS...MAINLY DURING THE AFTERNOON.

AFTER THE FRONT MOVES THROUGH...CANADIAN HIGH PRESSURE WILL BUILD
INTO THE REGION FOR MONDAY INTO TUESDAY...RESULTING MORE SEASONABLE
TEMPERATURES AND DRY CONDITIONS.
&&

.AVIATION...SHOWERS AND THUNDERSTORMS OVER EASTERN MINNESOTA WILL
TRY TO MOVE EAST TONIGHT INTO CENTRAL AND NORTH-CENTRAL WISCONSIN.
LATEST MESO MODELS AND ALSO THE RUC/NAM SHOW POTENTIAL FOR THIS TO
OCCUR LATE THIS EVENING INTO THE OVERNIGHT. THOUGH THINK THE
MAJORITY OF THUNDERSTORMS WILL REMAIN NORTHWEST OF THE TAF
SITES...UNCERTAINTY SEEMS TOO HIGH ATTM TO INCLUDE ANY THUNDER IN
THE TAFS. MODELS AND UPSTREAM OBS SUGGEST BKN MID AND HIGH CLOUDS
WILL BE OVERHEAD FOR MUCH OF THE DAY TOMORROW AFTER SHOWERS DEPART
EARLY TOMORROW MORNING.

MPC
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS LA CROSSE WI

231 PM CDT TUE AUG 21 2012

.SHORT TERM...THROUGH THURSDAY NIGHT
230 PM CDT TUE AUG 21 2012

MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES WEDNESDAY THROUGH
THURSDAY NIGHT.

SURFACE ANALYSIS THIS AFTERNOON SHOWS HIGH PRESSURE CENTERED OVER
EASTERN IOWA INTO CENTRAL WISCONSIN.

THE FIRST CONCERN IS WHETHER ANY VALLEY FOG WILL FORM AGAIN
TONIGHT. THE SURFACE HIGH WILL BE PULLING OFF TO THE SOUTHEAST AND
SHOULD BE CENTERED OVER INDIANA BY LATE TONIGHT. BOTH THE 21.12Z
NAM AND GFS SUGGEST A WARM FRONT WILL DEVELOP IN THE RETURN FLOW
FROM SOUTH DAKOTA INTO MISSOURI. AS THIS OCCURS...BOTH MODELS
ACTUALLY SHOW A LITTLE BIT OF RIDGING DEVELOPING NORTH OF THE
FRONT AND OVER THE AREA. THIS SHOULD ALLOW THE SURFACE WINDS TO
DECOUPLE ONCE AGAIN AND DEW POINTS SHOULD RECOVER INTO THE UPPER
40S. SKIES WILL BE CLEAR OVERNIGHT SO PLENTY OF POSITIVES FOR THE
FOG. BOTH THE NAM AND 21.17Z RAP BUFKIT SOUNDING FOR KLSE SHOW
SOUTHWEST WINDS AROUND 20 KNOTS JUST ABOVE THE SURFACE UP THROUGH
ABOUT 3 OR 4 THOUSAND FEET. THIS IS VERY SIMILAR TO A COUPLE OF
NIGHTS AGO EXPECT THE WINDS ARE ABOUT 180 DEGREES DIFFERENT IN
DIRECTION AND MAYBE A LITTLE STRONGER TONIGHT. SOME FOG DID FORM
IN THESE SIMILAR CONDITIONS SATURDAY MORNING SO PLAN TO INCLUDE A
MENTION OF PATCHY FOG.

THE NEXT CONCERN IS WHETHER ANY RAIN WILL FORM WEDNESDAY AND
WEDNESDAY NIGHT IN THE RETURN FLOW. MODEL DIFFERENCES CONTINUE
WITH THE NAM AND GFS STILL SHOWING SOME RAIN DEVELOPING WHILE THE
21.00Z ECMWF REMAINS DRY. WHETHER THIS RAIN DEVELOPS OR NOT
DEPENDS ON HOW MUCH LOW LEVEL THERMODYNAMICS COME INTO PLAY. THE
NAM CONTINUES TO BE THE STRONGEST WITH THIS FORCING SHOWING WEAK
FRONTOGENESIS IN THE 1000-500 MB LAYER NORTH OF THE WARM FRONT.
THE ECMWF ALSO HAS A LITTLE BIT OF FRONTOGENESIS BUT ONLY UP
THROUGH 700 MB. THE BIG DIFFERENCE COMES IN THE ISENTROPIC
RESPONSE. THE NAM GENERATES UP TO 10 UBAR/S ON THE 310K SURFACE
WHILE THE GFS ONLY HAS ABOUT 3 UBAR/S AND THE ECMWF HAS BETWEEN 1
AND 2 UBAR/S. IF THIS RAIN DOES DEVELOP...THE NAM BUFKIT SOUNDINGS
SHOW CLOUD BASES WOULD BE ABOUT 10K FEET WITH LOTS OF DRY AIR
BELOW. WOULD NOT EXPECT MUCH MORE THAN SOME SPRINKLES OR A QUICK
SHOWER WITH A COUPLE HUNDREDTHS QPF.

THE MODEL DIFFERENCES CONTINUE INTO THURSDAY AND THURSDAY NIGHT AS
WELL. THE SHORT WAVE TROUGH COMING ONTO THE PACIFIC NORTHWEST
COAST TODAY WILL TOP THE ROCKIES AND START MOVING ACROSS THE UPPER
MIDWEST. THE ECMWF HAS BEEN VERY CONSISTENT SHOWING THE FILLING
UPPER LEVEL LOW WITH THIS SYSTEM TO BE MOVING NORTHEAST INTO
CENTRAL CANADA WHILE THE SHORT WAVE TROUGH COMES THROUGH WITH A
POSITIVE TILT. THE NAM AND GFS ARE SUGGESTING THAT A PIECE OF
ENERGY WILL BREAK OUT OF THE MEAN LONG WAVE TROUGH AXIS OR A NEW
SHORT WAVE TROUGH DEVELOPS IN THE LEE OF THE ROCKIES WEDNESDAY.
THESE MODELS THEN BRING THIS SHORT WAVE TROUGH ACROSS THE AREA
WITH A NEUTRAL TO NEGATIVE TILT AND QUICKER THAN THE POSITIVE
TILT OF THE ECMWF. AT THIS POINT...CONFIDENCE ON WHICH SOLUTION
WILL VERIFY IS NOT HIGH SO HAVE TRIED TO COMPROMISE BETWEEN THE
TWO WITH A SLIGHT NOD TOWARD THE ECMWF SOLUTION. WILL SHOW A SMALL
CHANCE OF RAIN ACROSS THE FAR NORTH THURSDAY MORNING AHEAD OF THE
ADVANCING WARM FRONT AND THEN 20 TO 30 PERCENT CHANCES DURING THE
AFTERNOON ACROSS THE WEST AND NORTH AS THE FORCING STARTS TO
INCREASE AHEAD OF THE APPROACHING SYSTEM. AS THE SHORT WAVE TROUGH
THEN COMES INTO LATER THURSDAY...IT SHOULD PRODUCE AROUND 4 PVU/S
OF VORTICITY ADVECTION IN THE 500-300 MB LAYER. NOT MUCH OF
SURFACE REFLECTION WITH THIS SYSTEM SO ONLY SOME WEAK
FRONTOGENESIS IN THE 1000-850 MB LAYER. SOME WEAK UP GLIDE OF 1-2
UBAR/S SHOULD CONTINUE ON THE 310K SURFACE ALONG WITH GETTING
INTO THE EASTERN AND CONVERGENT SIDE OF THE MOISTURE TRANSPORT
AXIS. ALL THIS FORCING LOOKS TO BE AT ITS STRONGEST THURSDAY NIGHT
ACROSS THE NORTH AND DID INCREASE THE RAIN CHANCE TO AROUND 60
THERE.

.LONG TERM...FRIDAY THROUGH TUESDAY
230 PM CDT TUE AUG 21 2012

THE RAIN THAT DEVELOPS THURSDAY/THURSDAY NIGHT SHOULD BE COMING TO
AN END FRIDAY INTO FRIDAY NIGHT AS THE SHORT WAVE TROUGH MOVES
PAST THE AREA. THE NEXT PIECE OF ENERGY WILL QUICKLY APPROACH FROM
THE WEST COAST WITH THE UPPER LEVEL LOW AGAIN MOVING ACROSS CANADA
ALLOWING A SOUTHWEST FLOW ALOFT TO DEVELOP ACROSS THE UPPER
MIDWEST. INITIALLY THE MODELS ARE IN GOOD AGREEMENT THAT A SHORT
WAVE TROUGH WILL BE IN THIS SOUTHWEST FLOW OVER THE MID PLAINS
STATES SATURDAY NIGHT BUT THEN DIVERGE AS THEY START TO LIFT THIS
WAVE NORTHEAST. THE GFS FLATTENS THIS WAVE OUT AND LIFTS IT
THROUGH QUICKER THAN EITHER THE 21.12Z GEM OR ECMWF. THE ECMWF IS
THE STRONGEST AND SLOWEST LIFTING THIS WAVE TO THE NORTHEAST. THE
DIFFERENCES COULD BE STEMMING FROM THE WIDE RANGE OF SOLUTIONS
THAT ARE SHOWING UP WITH A POTENTIAL TROPICAL SYSTEM APPROACHING
THE SOUTHEAST U.S. AND FOR NOW HAVE STAYED WITH THE MODEL
CONSENSUS GRIDS WITH 30 TO 50 PERCENT RAIN CHANCES SATURDAY NIGHT
THROUGH SUNDAY NIGHT WITH THE SYSTEM THEN MOVING PAST MONDAY.

.AVIATION...THROUGH 18Z WEDNESDAY
1152 AM CDT TUE AUG 21 2012

MAIN CONCERN WILL BE RIVER VALLEY FOG/STRATUS POTENTIAL AGAIN
WEDNESDAY MORNING AT KLSE. HIGH PRESSURE WILL MAINTAIN CONTROL
ACROSS THE AREA FOR DRY/QUIET CONDITIONS. WITH RIDGE AXIS OVERHEAD
THROUGH THE NIGHTTIME HOURS...LOOK FOR CLEAR SKIES/LIGHT
WINDS AND A DRY AIRMASS. THIS WILL AGAIN SET UP RADIATIONAL FOG
CONDITIONS IN THE MISSISSIPPI RIVER CHANNEL WITH RELATIVELY WARMER WATER.
MODELS HOWEVER SHOWING FAIRLY BREEZY SOUTHWEST WINDS AT BLUFF-TOP
WHICH WILL LIKELY KEEP THE VISIBILITY UP AT KLSE AND PERHAPS
DEVELOP MORE OF A IFR/LIFR STRATUS CEILING INSTEAD. FAIRLY
CONFIDENT THIS WILL HAPPEN ALONG SOME OF THE MISSISSIPPI
CHANNEL/VALLEY...BUT NOT OVERLY CONFIDENT AT KLSE ITSELF. FOR
NOW...WILL INCLUDE VCFG MENTION IN THE 11-14Z TIME FRAME ALONG
WITH A SCT003 MENTION. DONT SEE ANY PROBLEMS AT KRST WITH VFR
CONDITION EXPECTED THROUGH 18Z.

.ARX WATCHES/WARNINGS/ADVISORIES...
230 PM CDT TUE AUG 21 2012

WI...NONE.
MN...NONE.
IA...NONE.

SHORT TERM...04
LONG TERM...04
AVIATION...DAS

AREA FORECAST DISCUSSION

NWS CHARLESTON SC

140 AM EDT THU AUG 23 2012

.SYNOPSIS...
WEAK LOW PRESSURE WILL MOVE UP THE COAST TONIGHT AND THURSDAY. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTHEAST FRIDAY THROUGH THE
WEEKEND AND LINGER OVER THE EASTERN SEABOARD INTO EARLY NEXT WEEK.

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
WATER VAPOR IMAGERY AND RAP VORTICITY ANALYSIS SHOW A SECONDARY
SHORTWAVE MOVING INTO THE CSRA. THIS FEATURE IS FORECAST
TO CROSS THE AREA OVERNIGHT AS A WEAK WAVE OF LOW PRESSURE RIDES
NORTHEAST ALONG AN ILL-DEFINED STATIONARY FRONT THAT IS IN PLACE
ACROSS EASTERN SOUTH CAROLINA/GEORGIA. UVV ASSOCIATED WITH THE
SHORTWAVE IS ALREADY BEGINNING TO IMPINGE ACROSS THE MIDLANDS AND
CSRA WHERE A RECENT UPTICK IN SHOWER/TSTM ACTIVITY IS NOTED. BEST
CHANCES FOR MEASURABLE RAINFALL WILL BE FOUND AT THE COAST WHERE
THE COMBINATION OF ENHANCED UVV ALOFT AND LOW-LVL COASTAL
CONVERGENCE WILL SUPPORT SCATTERED SHOWERS/TSTMS. WILL MAINTAIN
20-30 PERCENT POPS AREA WIDE TONIGHT WITH THE HIGHEST GRIDDED POPS
REMAINING ACROSS THE COASTAL COUNTIES. WE HAVE INITIATED WITH A
BIT WARMER TEMPS EARLY THIS MORNING AND HAVE INCREASED LOW TEMPS A
BIT IN A FEW SPOTS GIVEN RECENT TRENDS.

.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
THURSDAY...THE UPPER TROUGH WILL BE STEADILY DAMPENING...WHILE
SUBTLE SURFACE WAVES TRACK ALONG THE WEAKENING STATIONARY FRONT
ALONG THE COASTLINE. BOTH THE 12Z GFS AND 12Z NAM ARE IN GOOD
AGREEMENT THAT SHOWERS/THUNDERSTORMS WILL INCREASE IN COVERAGE
THROUGH THE LATE MORNING AND EARLY AFTERNOON HOURS. CONVECTION
WILL BE ENHANCED BY ELONGATED SHORTWAVE ENERGY MOVING INTO THE
REGION DOWNSTREAM OF THE UPPER TROUGH AXIS TO THE WEST...AS WELL
AS LINGERING MOISTURE AND CONVERGENCE ALONG THE DISSIPATING
FRONT/DEVELOPING COASTAL TROUGH. HAVE THUS BUMPED UP RAIN CHANCES
A BIT FOR THURSDAY TO INDICATE SCATTERED THUNDERSTORMS DURING THE
PEAK HEATING/INSTABILITY PERIOD OF THE LATE AFTERNOON/EARLY
EVENING HOURS. PERSISTENT CLOUD COVER...NORTH/NORTHEAST LOW LEVEL
FLOW...AND LOWER HEIGHTS WITHIN THE WEAK UPPER TROUGH...WILL
SUPPRESS HIGH TEMPERATURES IN THE LOW TO MID 80S...SEVERAL DEGREES
BELOW SEASONAL NORMALS. EXPECT PRECIPITATION POTENTIAL TO DECREASE
OVERNIGHT AS THE SHORTWAVE AND ASSOCIATED DEEPEST MOISTURE PULLS
OFFSHORE.

FRIDAY AND SATURDAY...SURFACE HIGH PRESSURE WILL STEADILY BUILD
FROM THE NORTH/NORTHWEST...AS THE UPPER LEVEL PATTERN BECOMES
INCREASINGLY DIFFUSE. THERE IS SOME EVIDENCE THAT A SUBTLE AND
BROAD AREA OF LOW PRESSURE ALOFT WILL SET UP OVER THE MID ATLANTIC
STATES...AS WELL AS WEAK SHORTWAVE ENERGY EMBEDDED WITHIN.
HOWEVER...UPPER LEVEL SUPPORT WILL BE QUITE LACKING FOR THE
REMAINDER OF THE SHORT TERM PERIOD. CONVECTION FRIDAY AND
SATURDAY WILL THUS MAINLY BE DRIVEN BY TYPICAL DAYTIME
HEATING/INSTABILITY...SEABREEZE CONVERGENCE...AND ANY INFLUENCES
FROM A WEAK COASTAL TROUGH. HAVE THEREFORE INDICATED A MORE
TYPICAL SUMMERTIME CONVECTIVE SCHEME...WITH 20 TO 30 PERCENT POPS
ALONG AND INLAND OF THE SEABREEZE EACH AFTERNOON/EARLY EVENING.
PARTLY CLOUDY SKIES WILL GENERALLY PREVAIL...AND EXPECT HIGH
TEMPERATURES TO BE ON A WARMING TREND THROUGH SATURDAY...WHILE
STILL REMAINING A FEW DEGREES BELOW SEASONAL NORMALS.

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
FORECAST CONFIDENCE IN THE LONG TERM PERIOD IS QUITE LOW AND ALMOST
SOLELY DEPENDS ON THE EVENTUAL TRACK AND INTENSITY OF TROPICAL
STORM ISAAC. PREFER TO REMAIN RATHER GENERIC AT THIS TIME...FAVORING
A SOLUTION SIMILAR TO EARLIER GFS MODEL RUNS...WITH CHANCE POPS
BEGINNING MONDAY AND CONTINUING THROUGH MID WEEK. POTENTIAL
IMPACTS AND FORECAST DETAILS WILL COME MORE INTO FOCUS AS FORECAST
CONFIDENCE INCREASES. CONTINUE TO STAY TUNED TO NATIONAL HURRICANE
CENTER ADVISORIES ON TROPICAL STORM ISAAC FOR THE LATEST FORECAST
TRACK AND INTENSITY INFORMATION.

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
OVERNIGHT THERE IS A RISK FOR PERIODS OF MVFR CIGS WHICH WILL BE
ON THE DIFFICULT SIDE TO PIN DOWN. TOWARD DAYBREAK...MODEL FORECAST
SOUNDINGS SUGGEST IFR CIGS AT KSAV ONCE AGAIN AND WE HAVE OPTED FOR
SOME LOWER CIGS AROUND DAYBREAK THERE.

MVFR CIGS SEEM FAIRLY LIKELY INTO LATE MORNING TODAY THEN VFR THIS
AFTERNOON AND EVENING. ISOLATED TO SCATTERED SHOWERS AND A FEW
TSTMS EXPECTED TO DEVELOP MID TO LATE AFTERNOON WITH THE SEA
BREEZE SLUGGISH TO MOVE INLAND.

EXTENDED AVIATION OUTLOOK...SCATTERED SHOWERS/TSTMS COULD IMPACT
THE TERMINALS AT ANYTIME DURING THE NEXT SEVERAL DAYS BRINGING A
RISK FOR SUB-VFR CONDITIONS.

.MARINE...
A DIMINISHING STATIONARY FRONT WILL LINGER IN THE VICINITY OF THE
LOCAL WATERS ON THURSDAY BEFORE DISSIPATING BY FRIDAY. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTH AND PERSIST THROUGH THE
WEEKEND. A RELATIVELY LIGHT AND ERRATIC FLOW CAN BE EXPECTED OVER
THE WATERS EARLY IN THE PERIOD...BEFORE A MORE SOLID NORTHEAST TO
ENE FLOW SETS UP ALONG THE PERIPHERY OF THE BUILDING HIGH PRESSURE
DURING THE WEEKEND. OVERALL...CONDITIONS ARE EXPECTED TO BE
RELATIVELY BENIGN AND REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA
THROUGH THE WEEKEND.

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

SYNOPSIS...
NEAR TERM...
SHORT TERM...79
LONG TERM...BSH
AVIATION...JRL
MARINE...

AREA FORECAST DISCUSSION

NWS NORTH PLATTE NE

1233 AM CDT THU AUG 23 2012

.AVIATION...

THE LOW LEVEL JET WILL CONTINUE THROUGH 09Z...WITH SOUNDINGS
INDICATING WINDS JUST ABOVE THE SURFACE OF 30KTS. LOW LEVEL WIND
SHEAR IS NOT EXPECTED AT THIS TIME. SCATTERED TO BROKEN CLOUD COVER
IS EXPECTED THROUGH THE PERIOD...HOWEVER CEILINGS WILL REMAIN VFR.
MODELS INDICATE A PERIOD OF -SHRA FOR KLBF BETWEEN 12Z-18Z WITH A
WEAK MID LEVEL DISTURBANCE. ALTHOUGH NOT IN KLBF TAF...A FEW BRIEF
LIGHT SHOWERS POSSIBLE BETWEEN 06Z AND 12Z. NO MENTION FOR KVTN
HOWEVER AS TIME SECTIONS SHOWED DRIER WITH INSUFFICIENT LIFT. WINDS
FOR THURSDAY TO GENERALLY BE LIGHT EAST TO NORTHEAST AOB 10KT.

.PREV DISCUSSION... /ISSUED 629 PM CDT WED AUG 22 2012/

FIRE WEATHER...

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

SHORT TERM/EXTENDED...NWS
AVIATION...CLB

AREA FORECAST DISCUSSION

NWS RALEIGH NC

310 AM EDT THU AUG 23 2012

.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL MOVE SLOWLY EAST ACROSS THE CAROLINAS
TODAY. SURFACE HIGH PRESSURE WILL STRENGTHEN OVER THE
CAROLINAS AND THE MID-ATLANTIC FRIDAY AND PERSIST INTO THE WEEKEND.

.NEAR TERM /THROUGH FRIDAY/...
AS OF 310 AM THURSDAY...

AN UPPER LEVEL TROUGH AXIS CONTINUES TO SLOWLY MOVE ACROSS WESTERN
NC...WHILE WATER VAPOR AND RAP 500MB VORT FIELDS SHOW MULTIPLE WEAK
DISTURBANCES MOVING NORTHEAST FROM GA TO EASTERN NC. DESPITE SOME
DRIER AIR ALOFT IN THE VICINITY OF THE TROUGH AXIS.. 00Z/23 RAOBS
FROM AROUND THE REGION SHOWED PLENTY OF MOISTURE BELOW 700MB AND PW
VALUES CONTINUE TO HOVER AROUND 1.5 INCHES. THUS... A ISOLATED
SHOWERS ARE STILL POSSIBLE THROUGH THE EARLY MORNING HOURS.

MEANWHILE...SURFACE HIGH PRESSURE CENTERED OVER WV WILL BUILD EAST
OF THE MOUNTAINS TODAY AND BEGIN TO SETTLE TOWARD NEW ENGLAND
THIS WEEKEND. DEWPOINTS ARE IN THE MID 50S WEST OF THE
MOUNTAINS..AND SOME OF THE DRIER AIR SHOULD BEGIN TO FILTER ACROSS
VA TOWARD NC TODAY. HOWEVER...THERE IS NOT A GOOD CONSENSUS FROM
THE OPERATIONAL MODELS ON HOW QUICKLY THE DRY AIR WILL PENETRATE
INTO NC..AND SREF PLUMES SHOW A RELATIVELY LARGE SPREAD IN DEWPOINTS
RANGING FROM THE UPPER 50S TO MID 60S THIS AFTERNOON. THE LOW LEVEL
FLOW IS NORTHEASTERLY BETWEEN THE HIGH TO THE WEST AND THE INVERTED
TROUGH/FRONTAL ZONE JUST OFFSHORE AND MAY NOT TAP THE DRIER AIR
UNTIL FRIDAY. GIVEN THAT DEWPOINTS MAY HOLD IN THE MID TO UPPER 60S
AND THE FACT THAT THE UPPER LEVEL TROUGH WILL BE MOVING SLOWLY
OVERHEAD AND CUTTING OFF INTO A WEAK UPPER LOW BY TONIGHT...WILL GO
WITH ABOVE MOST GUIDANCE TODAY WITH 30-40 POPS OVER THE COASTAL
PLAIN AND SANDHILLS.

INSTABILITY WILL CONTINUE TO RATHER WEAK WITH ONLY MINIMAL COOLING
ALOFT IN THE UPPER TROUGH....AND THE MID LEVEL FLOW/DEEP SHEAR HAS
WEAKENED TO LESS THAN 25KT. THE MAIN CONCERN FROM CONVECTION TODAY
WILL BE FROM SLOW MOVEMENT/PROPAGATION AND LOCALIZED FLOODING WITH
WEAK NORTHEASTERLY FLOW BENEATH THE SOUTHWESTERLY MID TO UPPER LEVEL
FLOW.

PERSISTENCE SHOULD BE APPROPRIATE FOR HIGHS AGAIN TODAY...LEADING TO
LOW TO MID 80S DEPENDING ON WHERE CLOUDS MID/HIGH CLOUDS THIN THE
MOST.

TONIGHT...
THE STRONGER OF THE UPPER DISTURBANCES EVIDENT UPSTREAM
SHOULD BE MOVING NORTHEAST ACROSS FAR EASTERN NC TONIGHT...SO WHILE
SHOWERS MAY LINGER LATER INTO THE EVENING...THERE SHOULD BE LESS
UPPER SUPPORT AFTER MIDNIGHT AND MOST OF THE AREA DRY. LOWS IN THE
MID 60S.

FRIDAY...
DRIER AIR LOW LEVEL AIR IS FORECAST TO FINALLY MAKE ITS WAY ACROSS
MUCH OF CENTRAL NC FRIDAY...AS HIGH PRESSURE RIDGE SETS UP ALONG THE
EAST COAST. OPERATIONAL MODELS WOULD SUGGEST AT LEAST ISOLATED
SHOWERS/STORMS MAY BE POSSIBLE FROM THE COASTAL PLAIN TO THE
SANDHILLS. THE UPPER LEVEL TROUGH OR WEAK LOW WILL BE OVERHEAD ON
FRIDAY WITH SOME DISTURBANCES POSSIBLY ROTATING ACROSS SC AND NC.
IF DEWPOINTS DO NOT FALL INTO THE LOWER 60S...THEN BETTER....ALBEIT
WEAK...ISNTABILITY MAY DEVELOP OVER THE PIEDMONT AND SLIGHT CHANCES
POPS COULD BE WARRANTED OVER THE ENTIRE AREA. QUITE ABIT MORE
SUNSHINE IS EXPECTED FRIDAY AFTERNOON AND HIGHS SHOULD BE 2-3
DEGREES WARMER REACHING THE MID TO UPPER 80S.

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 145 AM THURSDAY...

FOR FRIDAY NIGHT: THE NORTHERN STREAM SHORTWAVE TROUGH WILL BE
SHIFTING EASTWARD OFF THE CANADIAN MARITIMES... LEAVING THE FORMER
PERSISTENT EAST COAST TROUGH AS SIMPLY A WEAK ILL-DEFINED MID LEVEL
HEIGHT WEAKNESS SITTING OVER THE CAROLINAS. DRIER AIR (PRECIP WATER
SLIPPING BACK JUST UNDER SEASONAL NORMALS) SHOULD CONTINUE TO SLOWLY
FILTER SOUTHWARD INTO CENTRAL NC FROM THE NORTH... FED BY A HIGH
PRESSURE RIDGE EXTENDING FROM ITS CENTER OVER MAINE DOWN THROUGH THE
WRN/CENTRAL CAROLINAS. WEAK VORTICITY LOBES WILL SHEAR UP THE EAST
SIDE OF THE WEAK MID LEVEL LOW OVER COASTAL NC... BUT THE SURFACE
FRONT WILL HAVE SETTLED FAR ENOUGH SOUTHEAST OF THE FORECAST AREA
SUCH THAT IT WILL NOT PLAY A ROLE IN FRIDAY NIGHT`S WEATHER. WITH
THE LOSS OF HEATING AND CORRESPONDING REDUCTION IN INSTABILITY AND
WITH THE LACK OF A TRIGGER TO FORCE ASCENT... ISOLATED EVENING RAIN
CHANCES WILL DIMINISH OVERNIGHT. LIGHT SURFACE WINDS AND DECREASING
MID/HIGH CLOUDS FAVOR GOOD RADIATIONAL COOLING... AND POCKETS OF FOG
ARE POSSIBLE. LOWS 60-65 UNDER GENERALLY FAIR SKIES.

FOR SATURDAY/SATURDAY NIGHT: THE MID LEVEL VORTEX NOW OVER THE BC
COAST WILL PROGRESS EASTWARD THROUGH MANITOBA BY DAYBREAK SUNDAY...
WITH A SIGNIFICANT TROUGH SWEEPING ACROSS THE NORTHERN TIER OF THE
CONUS TO THE UPPER MIDWEST. THIS TROUGH`S APPROACH IS LIKELY TO HELP
NUDGE THE BAGGY LOW OVER THE CAROLINAS SLOWLY NORTHEASTWARD...
RESULTING IN SUBTLE HEIGHT RISES ALOFT OVER THE FORECAST AREA...
WHILE SURFACE RIDGING CONTINUES TO NOSE IN FROM THE NORTHEAST AS ITS
CENTER SHIFTS OFF THE NEW ENGLAND COAST. THE DRY AIR IN PLACE...
LIMITED INSTABILITY (MODEL MLCAPE ALL UNDER 400 J/KG)... AND NEUTRAL
TO SUBSIDING COLUMN SUPPORTS A DRY FORECAST. THE ONLY CAVEAT IS
POSSIBLE SEA BREEZE CONVECTION THAT COULD WORK INTO THE SOUTHEAST
CWA... AND WILL LEAVE A MENTION OF ISOLATED AFTERNOON STORMS HERE.
THE LOW LEVEL THERMAL STRUCTURE FROM FORECAST SOUNDINGS POINTS TO
HIGHS IN THE MID 80S... CLOSE TO THE EARLIER FORECAST AS WELL AS
STATISTICAL GUIDANCE. LOWS 61-66. -GIH

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 240 AM THURSDAY...

THE PATTERN OVER NORTH AMERICA DURING THIS TIME FRAME WILL FEATURE
THE VORTEX OVER THE MANITOBA/ONTARIO BORDER EARLY SUNDAY OPENING UP
WHILE ITS TROUGH SHIFTS EASTWARD ACROSS THE NRN GREAT LAKES/QUEBEC/
ST LAWRENCE VALLEY... CULMINATING IN A LONGWAVE TROUGH COVERING SE
CANADA AND THE NORTHEAST US BY WEDNESDAY. THIS TROUGH (PROPELLED BY
ADDITIONAL ENERGY DIVING INTO ITS BASE FROM THE NW) WILL STEADILY
WEAKEN THE SURFACE RIDGE OVER THE INTERIOR MID ATLANTIC... WHILE
BRINGING A COLD FRONT EASTWARD TOWARD THE APPALACHIANS. WITH SLOWLY
RECOVERING MOISTURE THROUGH THE COLUMN AND BOTH HEIGHT FALLS AND
INCREASING WINDS IN THE MID LEVELS... THE CHANCE FOR DIURNALLY-
DRIVEN SHOWERS AND THUNDERSTORMS WILL GRADUALLY INCREASE THROUGH
THIS PERIOD. OUTSIDE OF THIS PATTERN... OUR ATTENTION TURNS TO WHAT
IS EXPECTED BY THEN TO BE HURRICANE ISAAC. STARTING FROM AN
NHC-PREDICTED POSITION JUST OFF TAMPA FL ON MONDAY AND EXTRAPOLATING
THIS TRACK FOLLOWING THE LARGE SCALE PATTERN AND ENSEMBLE MODEL
GUIDANCE... NC COULD BE AFFECTED BY THE SYSTEM`S RAIN SHIELD BY
TUESDAY NIGHT OR WEDNESDAY. HOWEVER... IT IS FAR TOO EARLY TO
SPECULATE TOO MUCH ON THE TRACK AND PACE OF ISAAC THIS FAR OUT... SO
WILL MAINTAIN A CAUTIOUS APPROACH AT THIS TIME.

EXPECT DRY WEATHER SUNDAY THROUGH MONDAY WITH DRY/SINKING AIR AND
MID LEVEL RIDGING PERSISTING. LOW LEVEL THICKNESSES OVER 15 METERS
BELOW NORMAL SUPPORT HIGHS IN THE LOW-MID 80S SUNDAY. THICKNESSES
BEGIN TO REBOUND MONDAY BACK TOWARD NORMAL... EQUATING TO HIGHS IN
THE MID-UPPER 80S. WILL INDICATE A TREND TOWARD INCREASING MAINLY
AFTERNOON AND EVENING SHOWERS AND STORMS TUESDAY/WEDNESDAY. PEOPLE
IN NC AND THE SOUTHEAST STATES SHOULD CLOSELY MONITOR THE PROGRESS
AND NHC FORECASTS FOR ISAAC OVER THE NEXT SEVERAL DAYS. -GIH

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 140 AM THURSDAY...

MOSTLY VFR CONDITIONS OBSERVED AS OF 05Z...WITH A FEW SITES
REPORTING MVFR VSBYS. SKIES ARE CLEARING OVER THE WESTERN PIEDMONT
AS THE WESTERN EDGE OF THE MAIN MID/HIGH CLOUD SHIELD IS SHIFTING
SLIGHTLY EASTWARD. WITH LOCALLY HEAVY RAIN HAVING FALLEN LAST
EVENING AROUND FORSYTH AND GUILFORD COUNTIES...VSBYS AT KINT AND
KGSO COULD FALL TO IFR AND LIFR IF THE CLEARING PERSISTS.
ELSEWHERE...MOST SITES WILL SEE MVFR VSBYS DEVELOPING BY 09Z...WITH
PATCHY IFR VSBYS AND STRATUS POSSIBLE.

AFTER 12Z...CONDITIONS WILL IMPROVE BY 14Z WITH SCATTERED CUMULI
DEVELOPING. CLOUD BASES WILL BE ABOVE 4K FT AT KINT/KGSO BUT MAY
REMAIN AROUND 3K FT FROM KRDU TO KRWI AND KFAY UNTIL MID AFTERNOON.
THE BEST CHANCE OF SCATTERED SHOWERS AND ISOLATED STORMS WILL BE
OVER THE COASTAL PLAIN AND SOUTHERN PIEDMONT....FROM KRWI TO KFAY TO
KMEB/KAFP THIS AFTERNOON.

OUTLOOK...
THE UPPER LEVEL TROUGH THAT HAS BEEN RESPONSIBLE FOR THE
UNSETTLED WEATHER PATTERN RECENTLY IS EXPECTED TO GRADUALLY WEAKEN
AND LIFT NORTHWARD THROUGH THE END OF THE WEEK. THIS SUGGESTS A
GRADUAL IMPROVEMENT (I.E. FEWER SHOWERS AND T-STORMS) THROUGH THE
WEEKEND...WITH MOSTLY VFR CONDITIONS EXPECTED FOR THE PERIOD.

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

SYNOPSIS...WSS
NEAR TERM...SMITH
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...KRR/SMITH

AREA FORECAST DISCUSSION

NWS CHARLESTON WV

345 AM EDT THU AUG 23 2012

.SYNOPSIS...
HIGH PRESSURE AND WEAK FLOW DOMINATE THROUGH THE WEEKEND. WEAKENING
FRONT AND ASSOCIATED DISTURBANCE ALOFT PASSES LATE MONDAY INTO
TUESDAY. TO THE SOUTH...TRACKING COURSE/PROGRESS/STRENGTH OF ISAAC.

.NEAR TERM /THROUGH TONIGHT/...
LATEST RAP SHOWS UPPER TROUGH AXIS HAS FINALLY PASSED TO THE
EAST...WITH ONLY A FEW SPRINKLES STILL REMAINING OVER SOUTHERN
POCAHONTAS COUNTY. HIGH PRESSURE WILL CONTINUE AT THE
SURFACE...WITH A MAINLY WARM AND SUNNY DAY AHEAD. MODELS SHOWING
JUST ENOUGH MOISTURE THIS AFTERNOON...AND SOME WEAK BOUNDARY LAYER
CONVERGENCE/UPSLOPE FLOW IN THE WV MOUNTAINS...SO ADDED SOME
SCATTERED POPS...AND EXPANDED THE ISOLATED POPS A LITTLE IN OUR
EXTREME EASTERN ZONES. AS THE SLOW WARMING TREND CONTINUES...EXPECT
TODAY TO BE A DEGREE OR TWO WARMER THAN YESTERDAY. PREVIOUS FORECAST
FOR TODAYS HIGHS LOOKED GOOD AND MADE NO SIGNIFICANT CHANGES THERE.
ONLY SMALL ADJUSTMENTS MADE TO TONIGHT LOWS AS WELL BY BLENDING IN
THE MET WHICH HAS BEEN OUTPERFORMING THE MAV FOR LOWS RECENTLY. THIS
RESULTED IN A BIT WARMER FORECAST IN THE NORTHERN MOUNTAIN ZONES.

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
NO BIG CHANGES. DID DECIDE TO INCLUDE A SMALL 30 POP EMBEDDED IN
THE SLIGHT CHANCE 20 POP AREA...THAT WE HAVE BEEN CONSISTENCY RIDING
WITH FOR FRIDAY AND SATURDAY AFTERNOON AND EVENING. FORECAST
SOUNDINGS STILL INDICATE THE HEATING AND WEAK FLOW COULD CAUSE SOME
MOUNTAIN THERMALS TO BREAK THROUGH THE MID LEVEL CAP. WITH A WEAK
DRIFT POSSIBLE OFF THE MOUNTAINS TO THE WEST...DID INCLUDE A SLIGHT
CHANCE POP REACHING BACK TOWARD INTERSTATE 79 AND CORRIDOR G IN WV
BY LATE AFTERNOON OR EARLY EVENING.

BUT THE MAIN THEME CONTINUES TO THE THE WARM AFTERNOONS. DID
INCREASE MAXIMUM TEMPERATURES A FEW DEGREES IN SOME OF THE WESTERN
RIVER VALLEYS FOR FRIDAY AND SATURDAY...WITH THE DRY GROUND.

ANY WEAK UPSLOPE FLOW AT 925/850 MB SEEMS TO BE GONE BY SUNDAY. SO
MOST POPS AOB 14 PERCENT FOR SUNDAY.

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
LOW LEVEL FLOW BECOMES MORE SOUTHERLY SATURDAY NIGHT...AS A LOW
PRESSURE SYSTEM APPROACHES THE GREAT LAKES REGION. THIS FLOW WILL
BRING WARMER AIR INTO THE AREA SAT NIGHT...PER GFS SOLUTION. THE
ECMWF IS SLOWER AND FURTHER SOUTH WITH THE SFC LOW PRESSURE SYSTEM
MOVING IT INTO THE OH VALLEY BY 12Z MONDAY.

MEANTIME...SFC HIGH PRESSURE WILL KEEP WARM AND DRY WEATHER
THROUGH AT LEAST MONDAY. HOWEVER...INTRODUCE SLIGHT CHANCE POPS ON
MONDAY PER GFS SOLN...AND BRING CHANCE POPS FOR TUESDAY WITH A
COLD FRONT PASSING THROUGH. UNCERTAINTY WITH THIS SYSTEM
EXIST...SO EXPECT CHANGES IN THE NEXT COUPLE OF DAYS.

ROLLED WITH HPC TEMPERATURES THROUGH THE PERIOD.

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
BASED ON T/TD SPREAD SIMILAR TO LAST NIGHT...LARGELY BASED DENSE FOG
FORMATION ON WHAT HAPPENED LAST NIGHT. ONE MAJOR EXCEPTION IS KPKB
WHERE THE DEW POINT IS A COUPLE DEGREES LOWER THAN THIS TIME LAST
NIGHT...SO DELAYED ONSET OF FOG THERE JUST A BIT. AT ANY
RATE...EXPECTING DROPS INTO IFR/LIFR BETWEEN 08Z AND 10Z...WITH THE
EXCEPTION OF KBKW.

VFR SHOULD RETURN 12Z-13Z AS FOG DISSIPATES...WITH VFR AND LIGHT
FLOW EXPECTED FOR THE REST OF THE DAY. THERE SHOULD AGAIN BE SOME
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS OVER MOUNTAINS THIS
AFTERNOON.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING AND EXTENT OF FOG COULD VARY.

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.

DATE THU 08/23/12
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY M M H H L H H H H H H H
HTS CONSISTENCY H H H L L H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY L L L L L M H H H H H H
PKB CONSISTENCY H H M L L H H H H H H H
CKB CONSISTENCY L L L L L H H H H H H H

AFTER 06Z FRIDAY...
NO SIGNIFICANT IFR EXPECTED.

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

$$
SYNOPSIS...KTB/MZ
NEAR TERM...MZ
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...MZ

AREA FORECAST DISCUSSION

NWS NORMAN OK

342 AM CDT THU AUG 23 2012

.DISCUSSION...
WIDESPREAD MID AND HIGH CLOUDS OVERSPREAD MUCH OF THE REGION AS A
WEAK UPPER DISTURBANCE MOVES SOUTHWARD THROUGH THE FLOW. AS THIS
CONTINUE TO MOVE SOUTHWARD ACROSS THE REGION...MODEST MID LEVEL
ASCENT MAY ALLOW FOR VERY ISOLATED SHOWERS AND PERHAPS A STORM OR
TWO. RECENT RUNS OF THE HRRR DEPICT A LARGE AREA OF SHOWER AND
THUNDERSTORM ACTIVITY DEVELOPING BY 10Z TO 11Z OVER WESTERN
OKLAHOMA AND NORTH TEXAS. CONFIDENCE IS LOW IN THIS SCENARIO AND
WILL MAINTAIN ONLY SLIGHT CHANCE POPS THROUGH 12Z THIS MORNING.
SHOWERS AND STORMS SHOULD DEVELOP THIS MORNING OVER WESTERN
OKLAHOMA AND PERSIST INTO TONIGHT...SPREADING EASTWARD WITH TIME.
EXPECT THE BEST CHANCES TO REMAIN OVER NORTHWEST OKLAHOMA. AS
SUCH...DAYTIME MAX TEMPS WILL BE A FEW DEGREES COOLER ACROSS
WESTERN OKLAHOMA AND WESTERN NORTH TEXAS.

THE FORECAST THROUGH THE WEEKEND REMAINS GENERALLY UNCHANGED AS
MODELS CONTINUE TO SUGGEST WIDESPREAD PRECIP WITH A SERIES OF
UPPER WAVES TRANSLATING EWD ACROSS THE SOUTHERN PLAINS. PERHAPS
THE MOST POTENT OF THESE WILL MOVE THROUGH TOMORROW AFTERNOON
THROUGH SUNDAY MORNING...GENERATING WIDESPREAD SHOWERS AND STORMS
ALONG WITH LOCALLY HEAVY RAINFALL. THE GREATEST RAINFALL TOTALS
WILL LIKELY REMAIN ACROSS NORTHERN OKLAHOMA NEAR THE KANSAS
OKLAHOMA BORDER. HERE...ISOLATED AREAS MAY SEE UP TO 2.5 TO 3
INCHES OF RAIN. ELSEWHERE...TOTAL RAINFALL ACCUMULATION WILL RANGE
FROM AROUND AN INCH TO 2 INCHES THROUGH THE WEEKEND. PERHAPS THE
ONLY MINOR CHANGE TO THE FORECAST IS IN THE TIMING OF A SFC FRONT
SET TO PUSH THROUGH THE REGION LATE THIS WEEKEND INTO EARLY NEXT
WEEK. RECENT GFS/EURO HAVE COME IN A BIT FASTER WITH FRONTAL
PASSAGE AND WILL NUDGE FRONTAL POSITION AND ASSOCIATED RAIN
CHANCES SOUTHEASTWARD THROUGH MONDAY. WITH MANY AREAS SEEING
PERSISTENT CLOUD COVER AND SHOWER ACTIVITY...HIGH TEMPS WILL
LIKELY BE SEVERAL DEGREES BELOW AVERAGE...WITH SOME LOCATIONS
REMAINING IN THE UPPER 70S FRIDAY INTO SATURDAY.

HEADING INTO NEXT WEEK...UPPER RIDGE WILL BUILD BACK INTO THE
SOUTHERN PLAINS...THOUGH NOT TO THE STRENGTH IT DID IN JULY WHEN
WE WERE PLAGUED WITH PERSISTENT TRIPLE DIGIT TEMPERATURES.
STILL...MODEST RIDGING ALOFT WILL DIMINISH RAIN CHANCES AND LEAD
TO MORE SEASONABLE HIGH TEMPERATURES.

THE HURRICANE CENTER CONTINUES TO FORECAST TROPICAL STORM ISAAC
WILL TAKE A MORE EASTWARD PATH...ULTIMATELY MAKING LANDFALL
SOMEWHERE ALONG THE NORTHEAST GULF COAST. AS ISAAC REMAINS
SOMEWHAT DISORGANIZED...THE EXACT TRACK WILL BE VERY DIFFICULT
PINPOINT. THUS...IT REMAINS UNKNOWN IF ISAAC WILL HAVE ANY IMPACT
ALONG THE CENTRAL GULF COASTAL REGION OR ULTIMATELY THE SOUTHERN
PLAINS.

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 69 86 72 / 20 40 50 60
HOBART OK 91 68 89 70 / 30 40 50 50
WICHITA FALLS TX 94 70 91 74 / 20 30 30 30
GAGE OK 89 68 90 69 / 40 50 50 60
PONCA CITY OK 92 69 85 71 / 20 50 50 60
DURANT OK 93 68 89 73 / 10 10 20 40

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

30/AUSTIN

AREA FORECAST DISCUSSION

NWS ABERDEEN SD

407 AM CDT THU AUG 23 2012

.SHORT TERM...TODAY THROUGH SATURDAY
SHOWERS AND THUNDERSTORMS CONTINUE TO MOVE EASTWARD ACROSS THE
EASTERN PORTION OF THE CWA...SCATTERED IN VARIETY. THINGS ARE
SHIFTING EAST WITH THE MOVEMENT OF THE LOW LEVEL JET. EXPECTING
THIS TREND TO CONTINUE OVER THE NEXT SEVERAL HOURS WITH ACTIVITY
PUSHING EAST INTO MN LATER THIS MORNING. ANY REDEVELOPMENT LATER
THIS AFTERNOON IS LOOKING LESS LIKELY OVER OUR AREA WITH THE FRONT
PUSHING EASTWARD AT A GOOD CLIP. EXPECT MOST ACTIVITY LATER TODAY
TO BE ACROSS MN INTO SOUTHEAST SD AND PORTIONS OF IA AND NE. ONE
THING TO WATCH THIS MORNING THOUGH IS ANOTHER WEAK DISTURBANCE OFF
TO THE WEST OVER WY. WATER VAPOR SHOWS THIS AND THERE IS AN ACCAS
FIELD ACROSS NORTHEAST WY AND SOUTHWEST SD. HRRR IS ACTUALLY
SHOWING A FEW SPOTTY SPRINKLES/LIGHT SHOWERS ADVANCING ACROSS
WESTERN AND CENTRAL SD THROUGH THE MORNING. FOR NOW HAVE NOT
INCLUDED ANYTHING IN THE FORECAST AS OBS TO THE WEST INDICATE VERY
HIGH CEILINGS. THIS WILL NEED TO BE WATCHED THOUGH FOR POTENTIAL
OF ISO SHOWERS OR SPRINKLES ACROSS THE SOUTHWEST CWA LATER THIS
MORNING.

OTHERWISE...WILL BE WATCHING NEXT SYSTEM FOR FRIDAY AND FRIDAY
NIGHT. FAIRLY POTENT SHORTWAVE WILL BE ADVANCING EASTWARD ACROSS
THE INTERNATIONAL BORDER. SHARP SFC COLD FRONT WILL ALSO BE
TRACKING ACROSS THE DAKOTAS. WEAK TO MODERATE INSTABILITY DEVELOPS
OVER THE AREA FRIDAY AFTERNOON AND EVENING...BUT IT APPEARS BEST
SYNOPTIC SCALE LIFT WILL BE ACROSS ND. EXPECTING A FEW SHOWERS AND
STORMS TO DEVELOP SO LEFT POPS IN CHANCE CATEGORY WITH THE
THINKING THAT BETTER AREAL COVERAGE WILL BE ACROSS ND.

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY
AN UPPER RIDGE WILL BUILD OVER THE WESTERN CONUS DURING THE
PERIOD...WITH A VERY GRADUAL/SLOW EASTWARD PROGRESSION. THE
RESULTING STABLE CONDITIONS AND THE REDEVELOPMENT OF AN ELEVATED
MIXED LAYER WITH H7 TEMPERATURES WARMING FROM AROUND +5C TO
UPWARDS OF +14C TRANSLATES INTO AN EXTENDED DRY PERIOD WITH
TEMPERATURE GRADUAL WARMING TO ABOVE NORMAL FOR THE FIRST HALF OF
NEXT WEEK.

.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

VFR CONDITIONS WILL PREVAIL ACROSS THE AREA THROUGH THURSDAY
EVENING. SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE EAST
DURING THE OVERNIGHT HOURS. AT THIS TIME...HAVE NOT INTRODUCED
CIGS OR VSBYS BELOW VFR LEVELS...THOUGH IT IS POSSIBLE WITH ANY
THUNDERSTORMS THAT DEVELOP. THE MOST LIKELY SITE TO SEE THE
REDUCTIONS IN CIGS AND VSBYS WILL BE KATY...MAINLY BETWEEN 06Z AND
10Z.

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

$$
SHORT TERM...TMT
LONG TERM...CONNELLY
AVIATION...CONNELLY

WEATHER.GOV/ABERDEEN

AREA FORECAST DISCUSSION

NWS AMARILLO TX

437 AM CDT THU AUG 23 2012

.DISCUSSION...

THE GOING THINKING FOR THE FCST PACKAGE REMAINS PRETTY SIMILAR TO
PREVIOUS SHIFTS WITH A GENERALLY UNSETTLED PATTERN TO PREVAIL
THROUGH THE WEEKEND. IT DOES HOWEVER REMAIN DIFFICULT TO PIN DOWN
THE MOST LIKELY PERIODS FOR SHOWERS AND STORMS AS OVERALL FORCING
REMAINS PRETTY WEAK...AND SHRTWV ENERGY IS NOT BEING HANDLED WELL IN
THE MODELS. WHILE PARTS IF NOT MOST OF THE PANHANDLES SHOULD GET AT
LEAST SOME RAIN OVER THE NEXT 3 DAYS...MODEL DISCREPANCIES MAKE THIS
A LOW CONFIDENCE FCST. IT LOOKS LIKE THE FAVORED AREA FOR PRECIP MORE
OFTEN THAN NOT IS GOING TO BE THE ERN HALF OF THE CWA. WHILE ISOLATED
PULSE OR MULTICELL SVR WX MAY BE NOTED THE NEXT 3 AFTERNOONS...
WIDESPREAD SVR WX IS NOT EXPECTED DUE TO GENERALLY LIMITED SHEAR.

TODAY...
AS HAS BEEN THE CASE RECENTLY...MODEL PROGGED INSTABILITY VARIES
GREATLY AGAIN THIS AFTERNOON WITH ANYWHERE FROM NAM DEPICTED 700
J/KG TO RUC DEPICTED 2500 J/KG MLCAPE FCST THIS AFTERNOON. SOME OF
THE AFTERNOON INSTABILITY WILL HINGE ON THE EXTENT OF MID AND HIGH
CLOUDS...WHICH LOOK TO BE OVERDONE IN THE NAM. THEREFORE...SIMILAR
TO THIS PAST MON...WILL SIDE WITH THE SREF...WHICH SHOWS A GOOD
COMPROMISE CLOSER TO THE RUC WITH ABOUT 2000 J/KG MLCAPE BY LATER
THIS AFTERNOON. WHAT THE MODELS DO AGREE ON IS THAT INHIBITION
SHOULD BE WEAK THIS AFTERNOON. SO...IN SPITE OF ONLY WEAK SYNOPTIC
FORCING DUE TO A VERY WEAK SHRTWV...HAVE DECIDED TO INCREASE PRECIP
CHCS THIS AFTERNOON GIVEN THE PREFERENCE TOWARD HIGHER INSTABILITY.
ISOLATED STRONG TO SVR STORMS WILL BE POSSIBLE WITH LARGE HAIL AND
DAMAGING WINDS THE MAIN THREATS. THE SVR THREAT SHOULD DIMINISH AS
WE HEAD INTO THE NIGHTTIME HRS.

TONIGHT...
TONIGHT/S PD HAS BECOME QUITE TRICKY AS OVERNIGHT PRECIP CHCS WILL
BE SOMEWHAT MODULATED BY AFTERNOON CONVECTION /OR LACK THEREOF/. HAVE
LEFT GOING 40 PERCENT POPS...BUT THE THINKING IS THAT THE BEST CHCS
MAY BE BEFORE MIDNIGHT. IN SPITE OF AN INCREASING LLJ...IT APPEARS
THE AREA WILL BE UNDER THE INFLUENCE OF WEAK UPR SUBSIDENCE IN THE
WAKE OF THE AFTERNOON SHRTWV.

FRIDAY AND FRIDAY NIGHT...
AGAIN...CONFIDENCE AND TIMING OF SHRTWV RIPPLES OF ENERGY MAKE THESE
PDS TOUGH TO PIN DOWN...BUT AMPLE MSTR SHOULD AGAIN PROMOTE AT LEAST
CHCS FOR PRECIP. IT APPEARS THE BEST CHC MAY LIE WITH AFTERNOON
CONVECTION FRI AFTERNOON AND EVENING...BUT A MODEST LLJ COULD ALSO
PROMOTE PRECIP FRI NIGHT. AGAIN...DEPENDING ON INSTABILITY...SOME
SVR WX COULD BE NOTED FRI AFTERNOON.

SATURDAY THROUGH SUNDAY...
IF CURRENT MODEL PROGS HOLD...SAT AFTERNOON SHOULD BE A FAVORED
PERIOD FOR SHOWERS AND STORMS AS A FINAL...AND LIKELY STRONGER
SHRTWV TROUGH KICKS THROUGH THE AREA. HAVE LEFT SLIGHT CHCS FOR POPS
GOING FOR SUN...BUT PRECIP POTENTIAL DOES NOT LOOK ALL THAT
IMPRESSIVE ON SUN.

MONDAY ONWARD...
DISCREPANCY EXISTS IN MED RANGE MODELS WITH PLACEMENT AND STRENGTH
OF A REBUILDING UPR RIDGE OVER THE ERN ROCKIES/HIGH PLAINS...WITH
MUCH OF THE UNCERTAINTY DUE TO QUESTIONS ABOUT THE TRACK OF ISAAC
AND IT/S AFFECT ON THE UPR PATTERN. MOST SIGNS DO POINT TO A DRY AND
WARM PD FROM MON THROUGH MUCH OF THE NEXT WORK WEEK.

HEAVY RAIN THREAT...
WITH PWATS ABOVE 1.5 INCHES FOR A GOOD PART OF THE NEXT 3 DAYS...
DEEP WARM CLOUD LAYERS AOA 10KFT...TALL CAPE PROFILES...AND FAIRLY
SLOW STORM MOTIONS...SHOWERS AND STORMS STAND TO BE EFFICIENT PRECIP
PRODUCERS. HOWEVER...A LACK OF LOW LVL FOCUSING BNDRYS MAY KEEP
TRAINING TSTORMS TO A RELATIVE MINIMUM...KEEPING ANY FLASH FLOODING
ISOLATED.

TEMPERATURE-WISE...
HIGHS WILL GENERALLY BE NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE
WEEKEND...PUSHING A LITTLE FURTHER ABOVE NORMAL BY NEXT WEEK. LOWS
WILL BE ABOVE NORMAL THROUGH THE PD.

SIMPSON
&&

.FIRE WEATHER...

NEITHER ELEVATED NOR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
THROUGH THE NEXT SEVERAL DAYS...THOUGH BREEZY SOUTHERLY WINDS WILL BE
NOTED THROUGH SATURDAY.

SIMPSON
&&

.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 89 67 89 66 88 / 40 40 30 30 30
BEAVER OK 96 69 92 70 91 / 40 40 40 40 30
BOISE CITY OK 94 66 89 63 91 / 40 40 40 30 30
BORGER TX 92 70 92 69 89 / 40 40 30 30 30
BOYS RANCH TX 94 69 95 66 92 / 40 40 30 30 30
CANYON TX 89 67 91 66 89 / 40 40 30 20 30
CLARENDON TX 89 70 91 68 90 / 40 40 30 30 30
DALHART TX 93 65 93 63 89 / 40 40 30 30 30
GUYMON OK 94 69 91 66 91 / 40 40 40 40 30
HEREFORD TX 88 66 90 63 89 / 40 40 30 20 30
LIPSCOMB TX 92 70 88 70 89 / 40 40 40 40 30
PAMPA TX 89 68 89 67 86 / 40 40 40 30 30
SHAMROCK TX 90 70 90 69 89 / 40 40 40 40 30
WELLINGTON TX 92 70 93 70 92 / 40 40 40 30 30

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

13/09

AREA FORECAST DISCUSSION...UPDATED

NWS SAN ANGELO TX

1150 PM CDT WED AUG 22 2012

.DISCUSSION...
SEE 06Z AVIATION DISCUSSION BELOW.

.AVIATION...
NO SIGNIFICANT CHANGES TO THE PREVIOUS SET OF TAFS. VFR CONDITIONS
STILL EXPECTED ACROSS THE TAF SITES THROUGH THE NEXT 24 HOURS. WE
MAY SEE SCT MVFR CIGS EARLY IN THE MORNING FOR A BRIEF PERIOD...
BUT THE COVERAGE IS NOT EXPECTED TO BE WIDESPREAD ENOUGH TO
WARRANT ANY PREVAILING GROUPS AT ANY PARTICULAR SITE.
OTHERWISE...HAVE ONLY INSERTED A WIND DIRECTION CHANGE IN THE
MORNING FOR WINDS TURNING MORE SOUTHERLY AS MIXING WITH SOUTHERLY
WINDS OFF THE SURFACE TAKES PLACE DURING THE MORNING HOURS.

.PREV DISCUSSION... /ISSUED 944 PM CDT WED AUG 22 2012/

DISCUSSION...
HAVE UPDATED THE FORECAST TO REMOVE POPS/WX FOR THE REST OF THE
EVENING AS THE ISOLATED SHOWERS TO OUR SOUTH HAVE DISSIPATED WITH
THE LOSS OF DAYTIME HEATING. THERE ARE FEW SHOWERS TO OUR WEST IN
THE PERMIAN BASIN ASSOCIATED WITH WEAK UPPER LEVEL SHORTWAVE
ENERGY. HOWEVER...THESE SHOWERS HAVE BEEN FORMING AND WEAKENING
RATHER QUICKLY AS THEY MOVE EAST...AND WE EXPECT THAT TREND TO
CONTINUE...PREVENTING THEM FROM MAKING IT INTO OUR CWA. NO OTHER
SIGNIFICANT CHANGES WERE NEEDED.

PREV DISCUSSION... /ISSUED 607 PM CDT WED AUG 22 2012/

DISCUSSION...
SEE 00Z AVIATION DISCUSSION BELOW.

PREV DISCUSSION... /ISSUED 314 PM CDT WED AUG 22 2012/

DANIELS

.PRELIMINARY POINT TEMPS/POPS...
ABILENE 71 94 73 93 74 / 10 10 10 20 20
SAN ANGELO 71 95 73 95 75 / 10 10 10 20 20
JUNCTION 71 93 72 94 74 / 10 10 10 10 20

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS AMARILLO TX

1141 PM CDT WED AUG 22 2012

.AVIATION...
06Z TAF CYCLE
AN UPPER RIDGE WILL PREVAIL ACROSS THE PANHANDLES THROUGH THURSDAY
MORNING BEFORE MOVING OFF TO THE EAST AS AN UPPER TROUGH APPROACHES
FROM THE WEST BY THURSDAY AFTERNOON. CONVECTION MAY IMPACT THE
NORTHWEST TEXAS PANHANDLE AFTER 20Z THURSDAY...THEREFORE WILL INCLUDE
A VCTS REMARK FOR THE DALHART TAF SITE BETWEEN ABOUT 20Z THURSDAY AND
02Z FRIDAY. OTHERWISE...CONFIDENCE TOO LOW FOR THE GUYMON AND
AMARILLO TAF SITES WHICH MAY BE IMPACTED BY CONVECTION AFTER 00Z
FRIDAY. VFR CONDITIONS WILL PREVAIL. SOUTHEASTERLY WINDS 10 TO 20
KNOTS WITH SOME HIGHER GUSTS TONIGHT WILL BECOME SOUTHERLY TO
SOUTHWESTERLY 15 TO 25 KNOTS WITH HIGHER GUSTS AFTER 15Z
THURSDAY...AND THEN BECOME SOUTHERLY TO SOUTHEASTERLY AGAIN AFTER 00Z
FRIDAY 10 TO 20 KNOTS.

SCHNEIDER

.PREV DISCUSSION... /ISSUED 1042 PM CDT WED AUG 22 2012/

UPDATE...
HAVE TRIMMED POPS BACK ACROSS THE WESTERN ZONES TONIGHT AS AREA OF
THUNDERSTORMS CONTINUE TO WEAKEN AS THEY APPROACH THE TX BORDER.
HOWEVER WILL HOLD ONTO SLIGHT CHANCE POPS OVERNIGHT ACROSS THE
FORECAST AREA AS A LOW LEVEL JET SETS UP ACROSS THE SOUTHERN PLAINS.
REMAINDER OF THE FORECAST IS IN GOOD SHAPE WITH ONLY MINOR
ADJUSTMENTS TO SKY GRIDS NEEDED. UPDATED FORECASTS HAVE BEEN SENT.

CLK

PREV DISCUSSION... /ISSUED 630 PM CDT WED AUG 22 2012/

SCHNEIDER

PREV DISCUSSION... /ISSUED 321 PM CDT WED AUG 22 2012/

DISCUSSION...
ALREADY SEEING A TRANSITION FROM NORTHWESTERLY FLOW ALOFT TO MORE
WESTERLY FLOW ALOFT IN RESPONSE TO THE APPROACHING CUTOFF LOW
CURRENTLY IN SOUTHERLY CA.

MONDAY THROUGH WEDNESDAY...A RIDGE IS EXPECTED TO BUILD OVER THE HIGH
PLAINS...MINIMIZING THE CHANCE FOR RAIN AND BRINGING A WARMING TREND
AT LEAST TO START THE WEEK.

JOHNSON

FIRE WEATHER...
RELATIVELY HIGH ATMOSPHERIC MOISTURE...AND CONTINUED RAIN CHANCES
SHOULD PRECLUDE ANY ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS FOR
THE NEXT SEVERAL DAYS.

JOHNSON

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

11/05

AREA FORECAST DISCUSSION

NWS LINCOLN IL

1027 AM CDT THU AUG 23 2012

.DISCUSSION...
ISSUED 1027 AM CDT THU AUG 23 2012

MOSTLY SUNNY SKIES PREVAIL ACROSS CENTRAL ILLINOIS THIS MORNING.
WARM FRONTAL BOUNDARY HAS LIFTED INTO NORTHERN ILLINOIS...WHERE
MID-LEVEL CLOUD COVER AND A FEW LIGHT SHOWERS ARE OCCURRING IN THE
CHICAGO AREA. FURTHER SOUTHWEST...SCT MID-LEVEL CLOUDS CONTINUE TO
DEVELOP IN A ZONE OF WARM ADVECTION ACROSS THE ILLINOIS RIVER
VALLEY. HIGH-RES MODELS SUCH AS THE HRRR AND 4KM WRF-NMM SUGGEST
SCT SHOWERS WILL DEVELOP IN THIS AREA DURING THE AFTERNOON. BASED
ON THE 12Z KILX UPPER AIR SOUNDING SHOWING VERY DRY AIR BELOW
10000FT...THINK CHANCES OF ANY PRECIP REACHING THE GROUND ARE SLIM
TO NONE. WILL THEREFORE CONTINUE WITH A DRY FORECAST TODAY.
INCREASED CLOUD COVER WEST OF I-55...BUT CONTINUED WITH SUNNY
SKIES FURTHER EAST AND SOUTH. TEMPS SEEM TO BE RIGHT ON
TARGET...WITH AFTERNOON HIGHS REACHING THE LOWER 90S ACROSS THE
BOARD. ONLY MINOR CHANGES MADE TO GRIDS...SO ZONE UPDATE IS NOT
NEEDED AT THIS TIME.

BARNES
&&

.AVIATION...
ISSUED 638 AM CDT THU AUG 23 2012

VFR CONDITIONS WILL CONTINUE AT ALL TAF SITES NEXT 24HRS. ANY
CLOUDS TODAY AND TONIGHT WILL BE SCATTERED MID CLOUDS AND
SCATTERED TO BROKEN HIGH CIRRUS. LIGHT AND VARIABLE WINDS THIS
MORNING WILL BECOME SOUTHERLY TODAY AND THEN SOUTHEAST THIS
EVENING AROUND SUNSET.

AUTEN
&&

.PREV DISCUSSION...
ISSUED 306 AM CDT THU AUG 23 2012
FORECAST NOT MUCH OF A SHIFT FROM YESTERDAY. WEAK FLOW ALOFT OVER
THE MIDWEST WITH THE MAJORITY OF THE UPPER WAVE ACTIVITY NORTH OF
THE REGION. WITH THE LACK OF SIGNIFICANT FLOW...THE WARM AIR FROM
THE WESTERN HALF OF THE CONUS IS LEAKING INTO THE MIDWEST AT
MIDLEVELS OF THE ATMOSPHERE BRINGING ANOTHER BRIEF ROUND OF HOT
WEATHER FOR THE FORECAST THROUGH THE END OF THE WEEK. NEXT SYSTEM
ON APPROACH FOR THE LATTER HALF OF THE WEEKEND STILL A BIT OF A
CONUNDRUM FOR THE MODELS...WITH GFS A GENERAL MESS WITH AN OPEN
AND DIFFUSE WAVE STIRRING UP WAY TOO MUCH QPF... AND THE ECMWF
OVER DEVELOPING THE SURFACE SYSTEM WITH DYNAMICS UPSTAIRS A LITTLE
LACKING. FORECAST RESULTS VERY SIMILAR TO YESTERDAY.

SHORT TERM...TODAY AND TOMORROW...
HOT AND HOT...TEMPS AT 850 MB IN THE 19-20C RANGE BRINGING HIGH
TEMPS INTO THE 90S. MID AND HIGH LEVEL CLOUDS EXPECTED TO MOVE OUT...PLENTY
OF SUNSHINE IN PLACE FOR THE MAJORITY OF THE DAY AND A RATHER DRY
AIR COLUMN. SAME STORY FOR TOMORROW EXPECTED. DRY AND HOT. WILL
HAVE TO KEEP AN EYE ON RH VALUES FOR FIRE WEATHER CONCERNS. FOR
NOW...ABOVE RED FLAG CRITERIA AND RATHER WEAK WINDS...BUT THE
HEIGHTENED CONCERN FOR OUTDOOR BURNING CONTINUES IN THE WIDESPREAD
DROUGHT.

LONG TERM...SATURDAY THROUGH THURSDAY...
ALMOST THE SAME EXACT STORY AS YESTERDAY. SATURDAY IS ANOTHER HOT
DAY... POTENTIALLY TEMPERED A BIT BY APPROACHING CLOUD COVER LATE
IN THE DAY. GFS A BIT TOO WET WITH NEXT SYSTEM FOR THE SECOND HALF
OF THE WEEKEND...THE ECMWF A LITTLE TOO WOUND UP...AND TRACKING
THE OPEN WAVE ALOFT IS ALL OVER THE PLACE. GFS LOSING ITS SFC LOW
REPRESENTATION A BIT AND INSTEAD LOOKING FOR A MORE WIDESPREAD
ASCENT ALONG A SFC TROF...WHICH MAKES A BIT MORE SENSE IN THE
WEAK DYNAMICS. ECMWF IS A LITTLE SLOWER AND MORE SOUTHERLY WITH THE
BEGINNING OF THE DEVELOPMENT OF THE SYSTEM...NOT STRINGING OUT THE
ENERGY ALOFT...NOR ALONG A PRODUCTIVE SFC TROF...AND KEEPING THE SYSTEM
A BIT MORE COMPACT. ECMWF THEN OVERDOES IT A BIT INTO THE
MIDWEST...OVERDEEPENING THE SFC LOW SUN NIGHT WITH WEAK FLOW AND A
POS TILT TO THE WAVE IN THE FIRST PLACE. OPERATIONAL MODELS STILL
SHAKING OUT THE ACTUAL TRACK OF A WEAK SFC LOW WITH VERY LITTLE
FLOW ALOFT THIS FAR SOUTH. NAM/WRF FINALLY JOINING IN THE PARTY
FOR THE FORECAST AND COMING IN ON THE SIDE OF THE ECMWF FOR A
SLOWER START...AND IF ANYTHING...TRACKING THE SFC LOW A BIT TO THE
NORTH AND WEST ALONG THE MORE ACTIVE WAVE TRAIN. BEST CHANCES FOR
PRECIP WHERE THE SOLUTIONS CROSS...SUN NIGHT AND MONDAY.

HJS

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

931 AM CDT THU AUG 23 2012

.DISCUSSION...
917 AM CDT

MADE SOME MINOR EDITS TO THE SKY COVER/WEATHER GRIDS THROUGH THE
AFTERNOON...TO ACCOUNT FOR PERSISTENT PARTLY CLOUDY/PARTLY SUNNY
SKIES AND POSSIBLE SCATTERED SPRINKLES.

LATEST SATELLITE IMAGERY SHOWING AREA OF MID LEVEL CLOUD COVER
ACROSS NORTHERN ILLINOIS SLOWLY SHIFTING EAST...BUT WITH CLOUD
COVER CONTINUING TO DEVELOP ACROSS THE WESTERN FRINGE OF THIS
CLOUD SHIELD. LATEST RUC ANALYSIS INDICATING WAA CONTINUING ACROSS
NORTHERN ILLINOIS...WITH THE SHOWERS OBSERVED THIS MORNING PARTLY
DUE TO THIS WEAK ASCENT. AS A MID LEVEL WAVE SHIFTS TO THE EAST
ACROSS THE MIDWEST...WAA SHOULD CONTINUE INTO THE AFTERNOON WITH
EVEN SOME OF THE SHORT RANGE GUIDANCE INDICATING THIS POSSIBILITY.
THE LATEST HRRR IS SHOWING SOME SCATTERED SHOWER DEVELOPMENT FOR
THE REMAINDER OF THE DAY MAINLY FOR AREAS ALONG AND NORTH OF LINE
FROM PONTIAC TO CHICAGO. WITH THIS WEAK ASCENT EXPECTED IN THIS
GENERAL AREA AS WELL AS LATEST VISIBLE IMAGERY ALREADY SHOWING A
CUMILIFORM NATURE TO THE CLOUD DEVELOPMENT ACROSS EASTERN IOWA AND
WESTERN ILLINOIS...FELT IT WAS AT LEAST POSSIBLE FOR SCATTERED
SPRINKLES AND HAVE INCLUDED THIS POSSIBILITY IN THE FORECAST
THROUGH THIS AFTERNOON. DESPITE WEAK INSTABILITY IN
PLACE...FORCING SHALL BE WEAK ENOUGH FOR THUNDER TO BE
NONEXISTENT TODAY.

RODRIGUEZ

.PREV DISCUSSION...
303 AM CDT

THE WARMING TREND WILL CONTINUE INTO THE WEEKEND AND OVERALL
CONDITIONS LOOK TO BE DRY FOR THE NEXT SEVERAL DAYS...BUT THERE ARE
SEVERAL SUBTLETIES THAT COULD POINT TO SOME SPOTTY PRECIP
DEVELOPMENT BEFORE A WELL ORGANIZED SYSTEM ARRIVES SOMETIME SUNDAY.
MORNING MOISTURE CHANNEL IMAGERY SHOWS A LONGWAVE UPPER TROUGH AXIS
NOW PUSHING OFF THE EASTERN SEABOARD. MORE OF A ZONAL WEST TO EAST
FLOW IS SITUATED ACROSS THE NORTHERN CORRIDOR OF THE U.S. BUT THERE
ARE SEVERAL WEAK TROUGHS AND RIDGES EMBEDDED WITHIN THIS FLOW. THE
MORE NOTABLE FEATURES INCLUDE AN UPPER LOW LIFTING NORTHEASTWARD
ACROSS SASKATCHEWAN WITH AN ASSOCIATED TROUGH AXIS EXTENDING INTO
THE CENTRAL DAKOTAS...WHICH HAS FORCED WEAK RIDGING OUT AHEAD OF IT
WHICH DAMPENS OUT JUST TO THE WEST OF THE LOCAL AREA. A LARGE CLOSED
UPPER LOW IS NOW SPINNING OVER THE BRITISH COLUMBIA COAST WHILE A
CUTOFF LOW IS SLOWLY WORKING TOWARD THE FOUR CORNERS REGION. THESE
TWO SYSTEMS WILL BE THE PRIMARY FOCUS FOR PRECIP CHANCES LATER IN
THE WEEKEND. AT THE SURFACE...THE HIGH PRESSURE WHICH HAS DOMINATED
OUR LOCAL WEATHER THE PAST FEW DAYS HAS SHIFTED EASTWARD ACROSS THE
MID ATLANTIC REGION. ELONGATED LOW PRESSURE STRETCHES FROM CENTRAL
SASKATCHEWAN INTO WESTERN MINNESOTA AND INTO THE CENTRAL PLAINS IN
RESPONSE TO THE LOW AMPLITUDE TROUGH AXIS MENTIONED ABOVE.

TODAY THROUGH SATURDAY...THE DAMPENED UPPER RIDGING WILL CROSS THE
AREA THIS MORNING WITH MID LEVEL WARM ADVECTION ALREADY UNDERWAY. A
WEAK TROUGH FOLLOWS THE RIDGE INTO EARLY AFTERNOON BUT IS SLIGHTLY
MORE AMPLIFIED TO THE NORTH. IN ADDITION TO SOME INCREASED MID AND
HIGH CLOUD COVER SOME SCATTERED SPRINKLES ARE MOVING ACROSS THE AREA
AT THE CURRENT TIME BUT THESE WILL PROBABLY END BY MID MORNING.
CLOUD COVER APPEARS TO THIN THIS AFTERNOON...ESPECIALLY
WEST...ALLOWING FOR A DECENT AMOUNT OF SUNSHINE. WITH THE HIGH
MOVING OFF TO THE EAST THE PRESSURE GRADIENT WILL BE STRONGER THAN
PREVIOUS DAYS SUPPORTING A SOUTHERLY BREEZE. BETWEEN THE INCREASING
SUNSHINE...WARMER MID LEVELS...AND A SOUTH WIND...HIGHS WILL BE
WARMER THAN WEDNESDAY WITH READINGS IN THE UPPER 80S TO AROUND
90...WITH THE WARMEST READINGS WEST. FRIDAY...THE TROUGH WORKING
ACROSS SASKATCHEWAN/CENTRAL DAKOTAS THIS MORNING WILL MOVE ACROSS
THE AREA MIDDAY FRIDAY. THIS TROUGH WILL BE PRETTY STRETCHED OUT AND
LIFTING NORTHEASTWARD SO FORCING WILL BE PRETTY WEAK THIS FAR SOUTH.
AT THIS POINT SEE LITTLE SUPPORT FOR ORGANIZED SHOWER ACTIVITY SO
WILL GO WITH A DRY FORECAST. FRIDAY HIGHS SHOULD BE SLIGHTLY
WARMER THAN TODAY WITH MOST IF NOT ALL AREAS REACHING 90. SATURDAY
SHOULD BE A DRY DAY WITH HIGHS RIGHT AROUND THOSE OBSERVED FRIDAY.

SUNDAY THROUGH WEDNESDAY...THE CLOSED UPPER LOW CURRENTLY OVER THE
BRITISH COLUMBIA COAST WILL BE MOVING ACROSS CENTRAL/SOUTHERN
MANITOBA SATURDAY NIGHT. THE MAIN QUESTION IS HOW MUCH THE UPPER LOW
CURRENTLY APPROACHING THE FOUR CORNERS PHASES WITH THIS NORTHERN
STREAM SYSTEM. THE GFS AND ECMWF CONTINUE TO HAVE DIFFERENCES IN
THE MAGNITUDE OF PHASING AND ARE THEREFORE DIFFERENT WITH RESPECT
TO WHEN THIS SYSTEM CROSSES THE AREA. THE ECMWF IS LESS PHASED AND
THEREFORE KEEPS THE SOUTHERN STREAM TROUGH STRONGER WITH A BETTER
ORGANIZED SURFACE LOW ACCOMPANYING IT AS IT MOVES ACROSS THE MID
MISSISSIPPI RIVER VALLEY SUNDAY. THE GFS IS FASTER AND HAS THE
UPPER TROUGH PHASED TO A GREATER DEGREE. STILL PREFER THE ECMWF
OVERALL THOUGH IT IS JUST A BIT FASTER THAN EARLIER RUNS. THE 00Z
RUN WHICH HAS JUST ARRIVED IS SLIGHTLY MORE PHASED THAN THE 12Z
RUN BUT THE TIMING OF THE SYSTEM IS ABOUT THE SAME. THIS RESULTS
IN RAIN/THUNDER CHANCES SPREADING FROM WEST TO EAST SUNDAY AND
EXITING SOMETIME MONDAY. THE UPPER FLOW PATTERN WILL AMPLIFY AS
THIS SYSTEM MOVES EASTWARD WITH A LARGE RIDGE BUILDING TO THE
WEST. THIS WILL LEAVE THE AREA UNDER A NORTHWESTERLY UPPER FLOW
WHICH WILL ALLOW COOLER AIR TO SPREAD IN FROM THE NORTH MONDAY
NIGHT. FROM THAT POINT ON OUR WEATHER WILL BE DRIVEN BY HOW
PROGRESSIVE THE UPPER FLOW PATTERN BECOMES THROUGH THE REST OF
NEXT WEEK ALONG WITH INTERACTION BETWEEN IT AND TROPICAL SYSTEM
ISAAC WHICH WILL LIKELY BE ENTERING THE GULF OF MEXICO BY EARLY
NEXT WEEK.

MDB

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 12Z...

* SCATTERED SHOWERS LIKELY. CHANCES OF IMPACTING TERMINALS SMALL.

* INCREASING SOUTHERLY WINDS BECMG 10KT GUSTING TO 15KT THIS AFTERNOON.

KREIN

//DISCUSSION...UPDATED 12Z...

MAIN ISSUE THIS MORNING IS SOME SCATTERED SHOWERS FALLING FROM A
MID LEVEL CLOUD DECK. CLOUD BASES ACROSS THE REGION ARE BETWEEN
10KFT AND 15KFT...SO ANY PCPN HITTING THE GROUND SHOULD BE LIGHT.
LATEST RADAR IMAGERY SHOWS SOME HEAVIER SHOWERS TO THE NORTH OF
ORD/DPA. THESE SHOWERS HAVE A SOUTHEASTERLY TRACK...AND THERE IS
THE CHANCE THAT ORD COULD BE IMPACTED...BUT ANY PCPN WOULD BE VERY
BRIEF. OTHERWISE...EXPECTING THAT THE MID CLOUD DECK SHOULD BEGIN
TO MOVE OUT THIS AFTERNOON...LEAVE NO SIG CLOUD COVER. THE ONLY
OTHER CONCERN TODAY WILL BE WINDS. WINDS HAVE BEEN LIGHT AND
SOUTHERLY THROUGH THE NIGHT...BUT SHOULD BE INCREASING THROUGH THE
MORNING...BUT MAINTAINING A SOUTHERLY DIRECTION. EXPECT SPEEDS OF
10KT WITH OCNL GUSTS TO 15KT THIS AFTERNOON.

KREIN

//ORD AND MDW CONFIDENCE...UPDATED 12Z...

* MEDIUM TO HIGH CONFIDENCE IN TRENDS AND TRACK OF SHRA.

* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.

KREIN

//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...

FRIDAY NIGHT...VFR. WX NIL.

SATURDAY...VFR. WX NIL.

SUNDAY...CHANCE TSRA. OTHERWISE...VFR.

MONDAY...CHANCE TSRA EARLY. OTHERWISE...VFR.

TUESDAY...VFR. WX NIL.

WEDNESDAY...VFR. WX NIL.

KREIN

.MARINE...
250 AM CDT

HIGH PRESSURE EXTENDING FROM NEW ENGLAND SOUTHWESTWARD TO THE
TEXAS GULF COAST WILL REMAIN NEARLY STATIONARY THROUGH
SUNDAY...WHILE A WEAK TROUGH OF LOW PRESSURE EXTENDS FROM
MANITOBA THROUGH THE CENTRAL PLAINS. THIS WILL KEEP SOUTHERLY
WINDS OF AROUND 15-20KT...OCCASIONALLY TO AROUND 25 KT...OVER THE
LAKE. A STRENGTHENING LOW PRESSURE SYSTEM WILL DROP OUT OF THE
CANADIAN ROCKIES AND MOVE OUT OVER SOUTHERN MANITOBA SATURDAY.
THIS LOW WILL TRACK NORTHEAST TO HUDSON BAY BY SUNDAY NIGHT WHILE
DRAGGING A COLD FRONT ACROSS THE WESTERN GREAT LAKES
REGION...TURNING WINDS OVER LAKE MICHIGAN TO WESTERLY OR
NORTHWESTERLY BY SUNDAY.

KREIN

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

1043 AM CDT THU AUG 23 2012

.UPDATE...
A VERY MINOR UPDATE TO THE FCST HAS BEEN DONE TO HAVE IT REFLECT
CURRENT TRENDS.

SATELLITE SHOW CLOUDS OVER THE IMMEDIATE AREA ARE SLOWLY
DISSIPATING. THE CLOUDS OVER NORTHEAST ILLINOIS/EASTERN WISCONSIN
ARE BEING DRIVEN IN RESPONSE TO A VORT MAX MOVING THROUGH THE
AREA. RAP TRENDS SHOW LIFT INCREASING AGAIN LATE MORNING/AFTERNOON
AS A WEAKER VORT MAX MOVES INTO EASTERN IOWA. FCST SOUNDINGS
CONTINUE TO SHOW A DRY ATMOSPHERE BELOW 700MB SO ANY CLOUDS THAT
DEVELOP SHOULD BE IN THE 10-15 THOUSAND AGL RANGE BUT MID LEVEL
LAPSE RATES ARE MARGINAL. FCST SOUNDINGS DO SHOW MOISTURE ABOVE
THE LFC SO THERE IS THE POSSIBILITY OF THESE CLOUDS BEING ACCAS
WITH PERHAPS VIRGA.

MAX TEMPERATURES WERE RAISED SLIGHTLY IN THE SOUTHWEST CWFA BASED
ON WARMER READINGS THERE AT 15Z. IT WILL BE A VERY WARM DAY BUT
MIXING SHOULD ALLOW THE MID AND UPPER 50 DEW POINTS TO DROP INTO
THE UPPER 40S TO NEAR 55 DURING THE AFTERNOON. ..08..

.PREV DISCUSSION... /ISSUED 617 AM CDT THU AUG 23 2012/

AVIATION...
A SURFACE TROF OVER THE CENTRAL AND NORTHERN PLAINS WILL MOVE
SLOWLY EAST TODAY AND TONIGHT KEEPING SOUTHERLY WINDS OVER THE
FORECAST AREA THROUGH TONIGHT. VFR CONDITIONS WILL REMAIN OVER
THE AREA THROUGH THE PERIOD. SOME SPOTTY ELEVATED SHRA WILL BE
ASSOCIATED WITH SOME SCATTERED TO BROKEN MID CLOUDS ESPECIALLY
EAST OF THE MISSISSIPPI RIVER. SINCE THE AIR BELOW THE CLOUD
BASES WILL REMAIN DRY...ANY RAIN SHOULD EVAPORATE BEFORE REACHING
THE GROUND. THUNDERSTORMS WILL BE MOVING THROUGH THE NW HALF OF
IOWA TONIGHT. THESE STORMS SHOULD REMAIN WELL WEST OF THE ALL TAF
SITES THROUGH 12Z FRIDAY.

DLF

PREV DISCUSSION... /ISSUED 333 AM CDT THU AUG 23 2012/

SYNOPSIS...
THE UA ANALYSIS SHOWED NEAR ZONAL H5 FLOW IN PLACE OVER THE
WESTERN HALF OF THE U.S. SURFACE FEATURES EARLY THIS MORNING
INCLUDE LOW PRESSURE OVER EASTERN SD WITH A WARM FRONT EXTENDING
SOUTHEAST THROUGH NRN IA AND NORTHERN IL. A S/W OVER SD IN THE
WESTERLY FLOW WAS SUPPORT AN AREA OF SHRA/TSRA OVER EASTERN
SD/WESTERN MN EARLY THIS MORNING. FURTHER DOWN STREAM ELEVATED WAA
WAS RESULTING IN SOME HIGH BASED AC WITH SOME SPOTTY RETURNS ON
RADAR OVER NORTHEAST IA AND NRN IL. SO FAR SURFACE OBS UNDER THE
PRECIP HAVE NOT SHOWN ANY RAIN REPORTS...SO THE PCPN IS PROBABLY
EVAPORATING BEFORE REACHING THE GROUND.

SHORT TERM...TODAY AND TONIGHT...
THE NORTHERN PLAINS SW WILL CONTINUE EAST TODAY WITH THE BETTER
FORCING WITH THE WAVE STAYING WELL NORTH OF THE CWFA. THIS SHOULD
KEEP THE CLUSTER OF SHRA/TSRA JUST AHEAD OF WAVE MAINLY OVER MN
AND WI TODAY AND TONIGHT. THE AREA OF MID CLOUD/VIRGA WILL BE SLOW
TO MOVE OFF TO THE EAST TODAY. THE DEEP LAYER OF DRY AIR BELOW THE
CLOUD BASE THOUGH SHOULD CONTINUE TO CAUSE ANY PRECIPITATION TO
EVAPORATE SO WILL KEEP THE FORECAST DRY FOR TODAY. MODEL SOUNDINGS
SHOW A NEARLY DRY ADIABATIC LAPSE THROUGH 700MB TODAY INDICATING
DEEP MIXING. THIS SHOULD DRIVE TEMPERATURES INTO THE LOW TO MID
90S.

TONIGHT MODELS SHOW SHRA/TSRA ASSOCIATED WITH THE MN S/W MOVING
THROUGH THE NW HALF OF IA BUT DISSIPATING BEFORE REACHING THE EAST
CENTRAL AND SOUTHEAST COUNTIES. WILL KEEP THE FORECAST DRY
OVERNIGHT BUT WE SHOULD SEE...BLOW OFF CLOUDS...FROM THE
CONVECTION TO THE WEST SPREADING OVER THE CWFA. THE HIGH CLOUDS
AND LIGHT SOUTH WINDS WILL KEEP OVERNIGHT LOW IN THE MID 60S.

DLF

LONG TERM...FRIDAY THROUGH WEDNESDAY...
WARM...BREEZY AND DRY WEATHER CONTINUES FRIDAY THROUGH MUCH OF
SATURDAY...THEN FOCUS TURNS TO SYSTEM WITH POTENTIAL FOR SIGNIFICANT
RAINFALL LATE SATURDAY THROUGH SUNDAY.

MODEL FORECAST SOUNDINGS...OUTSIDE THE GFS WITH ITS CONTINUED POOR
HANDLING OF LOW LEVEL THERMAL AND MOISTURE FIELDS...SUGGEST ANOTHER
DAY OF DEEP MIXING TO AT LEAST 700 MB IN THE DRY LOW LEVEL SOUTHERLY
FLOW ON FRIDAY. THIS WOULD PLACE HIGHS AGAIN INTO THE LOWER TO MID 90S
WITH DEWPOINTS MIXING OUT INTO THE 50S...IF NOT UPPER 40S...AS THE
MONSOONAL MOISTURE AND HIGHER PW VALUES DO NOT LOOK TO REACH THE
AREA UNTIL FRIDAY NIGHT AT THE EARLIEST. A LIGHT S-SE LOW LEVEL FLOW
OVERNIGHT SHOULD HOLD MINS TO NO LOWER THAN THE 60S.

SATURDAY...MOISTURE ADVECTION AND FORCING AHEAD OF A MID LEVEL
SHORTWAVE MAY TRIGGER THUNDERSTORMS OVER THE WEST AND HAVE CHANCE
POPS IN PLACE. THIS WILL LIMIT HIGHS TO THE MID AND UPPER
80S...WHILE EAST OF THE MS RIVER REMAINS DRY AND REACHES CLOSER TO
90.

SATURDAY NIGHT INTO SUNDAY...A COMPLEX SYSTEM WILL PUSH THROUGH THE
AREA WITH ABUNDANT AVAILABLE MOISTURE TO PRODUCE WIDESPREAD
RAINFALL. WHILE DETAILS STILL VARY AMONG MODELS...ESPECIALLY WITH
RESPECT TO THE PLACEMENT AND TIMING OF A WEAK LOW LEVEL CIRCULATION
PASSING TO THE SOUTH...THERE IS ENOUGH AGREEMENT AND CONSISTENCY TO
JUSTIFY LIKELY POPS FOR SUNDAY. GFS AND ECMWF MODEL QPF TOTALS
CONTINUE TO PAINT WIDESPREAD 1 TO 2 INCH EVENT TOTALS FOR THE
REGION. HIGHS HAVE BEEN TRIMMED BACK TO THE UPPER 70S TO LOWER
80S...WHICH MAY STILL BE TOO WARM IF CLOUDS AND RAIN PREVAIL.

MONDAY THROUGH WEDNESDAY GENERALLY LOOKS DRY WITH NEAR TO ABOVE
NORMAL TEMPERATURES AS AN UPPER LEVEL RIDGE BUILDS TO THE WEST WITH
SURFACE HIGH PRESSURE OVER THE REGION.

SHEETS

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

AREA FORECAST DISCUSSION...UPDATED

NWS GRAY ME

1002 AM EDT THU AUG 23 2012

.SYNOPSIS...
LOW PRESSURE WILL TRACK EASTWARD THROUGH CENTRAL QUEBEC THIS
MORNING...DRAGGING A COLD FRONT INTO THE MOUNTAINS TODAY. HIGH
PRESSURE WILL BUILD OVER NORTHERN NEW ENGLAND ON FRIDAY AND SHIFT
OFFSHORE THIS WEEKEND. GENERALLY DRY AND SEASONABLY WARM
CONDITIONS ARE EXPECTED THROUGH EARLY NEXT WEEK.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...CIRRUS NOW MOVING ACROSS SOUTHERN NH AS MOISTURE SURGES
OUT AHEAD OF A MID LEVEL SHORT WAVE. OTHERWISE FOG HAS LIFTED AND
SKIES ARE CLEAR. TEMPERATURES ARE WARMING QUICKLY AND ARE A FEW
DEGREES WARMER THAN THEY WERE THIS TIME YESTERDAY. ADJUSTED
TEMPERATURES AND DEW POINTS SLIGHTLY BASED ON THESE TRENDS. ALSO
BASED ON THE LATEST RUN OF THE HRRR AND ONLY WEAK FRONTOGENESIS
PROGS REDUCED THE POPS FOR THIS AFTERNOON FROM CHANCE TO SLIGHT
CHANCE ACROSS OUR NORTHERN COUNTIES.

PREVIOUS DISCUSSION...CLEAR SKIES AND LIGHT WINDS ARE MAKING FOR
ANOTHER COOL NIGHT AWAY FROM THE COAST. ALREADY SEEING PATCHY
GROUND FOG DEVELOPING IN THE USUAL COOL SPOTS AND RIVER VALLEYS.
EXPECT THE TREND TO CONTINUE FOR THE NEXT COUPLE OF HRS. WITH THE
DRIER AIR MASS IN PLACE...EARLY DAY SUNSHINE WILL QUICKLY PUSH
TEMPS UP AND THE FOG WILL LIFT OUT AS THEY DO.

ANOTHER PLEASANT DAY IN STORE TODAY...WITH TEMPS WARMER IN THE
80S. WAA AHEAD OF THE SRN CANADA S/WV TROF WILL INCREASE MID LVL
TEMPS IN SRN NH SUPPORTIVE OF A RUN AT THE UPR 80S. THIS S/WV WILL
BE SHEARING OUT WITH TIME AND LIFTING NEWD. THIS WILL JUST PROVIDE
A GLANCING BLOW OF WEAK FORCING TO NRN NEW ENGLAND. AS SUCH...HAVE
KEPT POP TIED TO THE HIGHER TERRAIN...WHERE THE ELEVATED HEAT
SOURCE WILL BE THE MOST LIKELY IMPETUS FOR CONVECTION.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
CONSIDERING THE SHRA/TSTMS THAT DO DEVELOP THIS AFTN WILL BE
MOSTLY DIURNALLY DRIVEN...EXPECT THAT THEY WILL WEAKEN QUICKLY
AFTER SUNSET. AS HIGH PRES BUILD BACK IN BEHIND SFC TROF...WILL
SEE MORE PATCHY FOG IN THE VALLEYS.

FRI WILL BE NICE AGAIN...WITH TEMPS SLIGHTLY COOLER THAN TODAY.

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE PARKS ITSELF OVER NORTHERN NEW ENGLAND FOR
THE WEEKEND. THIS WILL BRING MILD SUNNY DAYS WITH AFTERNOON SEA
BREEZES ALONG THE COAST. DURING THE NIGHTTIME PERIODS...LOOK FOR
CHILLY CONDITIONS AND PATCHY FOG. STILL LOOKING FOR SOME MID TO
UPPER 40S IN THE MOUNTAINS.

A MORE SIGNIFICANT UPPER LEVEL TROUGH APPROACHES THE REGION BY
MONDAY NIGHT...ALLOWING A COLD FRONT TO SLIP THROUGH THE REGION
THROUGH TUESDAY MORNING. ALL MODELS AGREE THAT A FEW SCT SHOWERS
OR PSBLY A TSTM WILL CROSS THE REGION WITH THIS SYSTEM AS IT
RIDES THROUGH. OVERALL HOWEVER...DRY CONDS WILL CONTINUE FOR MUCH
OF THE EXTENDED FCST.

IT IS STILL WAY TOO EARLY TO PINPOINT THE TRACK OF ISAAC AT THIS
TIME. AFOREMENTIONED UPPER LEVEL TROUGH MAY STEER SYSTEM OUT TO
SEA LATER NEXT WEEK...OR MAY BYPASS THE SYSTEM ENTIRELY. REFER TO
UPDATES FROM THE NATIONAL HURRICANE CENTER AS THE SYSTEM BEGINS
TO INCREASE IN LATITUDE.

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
SHORT TERM...LOCAL IFR/LIFR CONDS EXPECTED AT KLEB/KHIE/KAUG THIS
AM IN VALLEY FOG. VFR CONDS TO PREVAIL THIS AFTN...WITH AN ISOLD
SHRA PSBL INVOF KHIE. PATCHY FOG WILL LIKELY DEVELOP AGAIN FOR
KLEB AND KHIE THU NGT.

LONG TERM...WILL LIKELY HAVE MORNING FOG IN LEBANON AND WHITEFIELD
EACH MORNING FROM AROUND 08Z-12Z BUT OTHERWISE EXPECT VFR
CONDITIONS. THERE IS ALSO SOME POTENTIAL FOR MARINE FOG DEVELOPING
OVER THE WATERS AND DRIFTING ONSHORE AT SOME POINT DURING THE
WEEKEND.

.MARINE...
SHORT TERM...WINDS AND SEA WILL REMAIN BLO SCA THRESHOLDS.

LONG TERM...A HIGH PRESSURE AXIS EXTENDING OVER THE GULF OF MAINE
THROUGH THIS WEEKEND WILL KEEP CONDITIONS TRANQUIL.

.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.

UPDATE...HANES

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

748 AM EDT THU AUG 23 2012

.UPDATE...
ISSUED AT 744 AM EDT THU AUG 23 2012
ALTHOUGH NOT COMPLETELY SURPRISED...THE CONVECTIVE FORECAST FOR
TODAY IS NOT PANNING OUT TOO WELL. AS THE SAYING GOES...WARM AIR
ADVECTION WAITS FOR NO ONE. THIS IS INDEED THE CASE CURRENTLY AS SCT
SHRA/TSRA ARE RAPIDLY FORMING WELL TO THE EAST OF LOW-LEVEL JET AXIS
IN AREA OF H7 MOISTURE ADVECTION /NOW INTO IRON COUNTY MICHIGAN/.
SPED UP PACE OF HIGHER POPS BRINGING THEM AS FAR EAST AS MARQUETTE
AND MENOMINEE COUNTIES THIS MORNING. DOES APPEAR THAT SHORTWAVE
ANALYZED ON RUC AND SEEN SOMEWHAT IN WV LOOP OVR NORTHEAST MN WILL
PUSH THE MORE CONCENTRATED AREA OF SHRA/TSRA OVER NORTHWEST WI
ACROSS WESTERN TIER THIS MORNING. WILL RAMP POPS UP IN THESE AREAS
AS WELL. AND LAST BUT NOT LEAST...ADDED MENTION OF FOG OVER EASTERN
CWA FOR NEXT COUPLE HOURS AS DECENT RADIATIONAL FOG DEVELOPED WHERE
WINDS ARE LIGHTEST OVER UPR MICHIGAN.
&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 516 AM EDT THU AUG 23 2012

THE BIG PICTURE VIEW HAS A SHORTWAVE TROUGH ORIENTED FROM
SASKATCHEWAN TO THE DAKOTAS. SHARPEST PORTION OF THE TROUGH...WITH
NOTABLE WIND SHIFT H7-H5 WAS MORE OVR CANADA VERSUS THE CONUS. JET
STREAK WAS SLIDING BY ON SOUTHERN EDGE OF THE TROUGH ACROSS WYOMING
INTO SOUTH DAKOTA. IN GENERAL A SFC TROUGH WAS LOCATED FROM
SASKATCHEWAN INTO NORTHERN NEBRASKA...BUT THERE WERE A COUPLE OF
AREAS OF LOWER PRESSURE NOTED WITHIN THE BROAD TROUGHING REGIME.

REGIONAL RADARS AND IR SATELLITE/LIGHTNING DETECTION SYSTEM SHOWED
ONE AREA OF SHRA/TSRA WAS ONGOING OVR EASTERN SOUTH DAKOTA INTO
SOUTHERN MINNESOTA ON THE NOSE OF THE HIGH PLAINS JET STREAK AND
WITHIN AREA OF STRONGER H85 TEMPERATURE ADVECTION JUST AHEAD OF MORE
CLOSED OFF SFC-H85 LOW CIRCULATION. ADDITIONAL SHRA/TSRA HAVE TAKEN
OFF SINCE 06Z JUST TO SOUTHWEST OF DLH AND ALSO INTO NORTHERN WI.
THESE SHRA/TSRA SEEM TO BE DRIVEN BY H85-H7 MOISTURE ADVECTION ON
NOSE OF 30-40 KT H85 JET NOSING INTO NORTHWEST WISCONSIN. BASED ON
RADAR TRENDS AND EXPECTED POSITION OF LOW-LEVEL JET THIS MORNING...
EXPECT PARTS OF CWA TO BE AFFECTED BY AT LEAST ISOLD SHRA/TSRA.
TREND CONTINUES THROUGH AFTERNOON WITH STRONGEST H85 CONVERGENCE AND
H85-H7 MOISTURE ADVECTION IMPACTING MAINLY WEST HALF OF CWA. KEPT
HIGHEST POPS OVER FAR WEST AND KEWEENAW...BUT SINCE THE LOW-LEVEL
JET ONLY SLIGHTLY WEAKENS AND H7 MOISTURE ADVECTION PERSISTS ATOP
STALLED OUT FRONTAL BOUNDARY OVER LAKE SUPERIOR ALONG WITH STEEP
MID-LEVEL LAPSE RATES...CANNOT COUNT OUT A SHRA/TSRA AT ANY LOCATION
OVR CWA TODAY. RISK OF SEVERE STORMS WOULD APPEAR LOW...BUT IF
CLEARING COULD OCCUR FOR A WHILE LATER THIS AFTERNOON IN THE
WEST...MLCAPES COULD PUSH TOWARD 1000 J/KG WHILE DEEP LAYER SHEAR
IMPROVES LATE TODAY /20-25 KTS/ AS SHORTWAVE TROUGH DRAWS CLOSER.

MAX TEMPERATURES KIND OF A CHALLENGE TODAY. DOES SEEM THAT IDEA OF
CONVECTIVE BLOWOFF/THICK H7-H5 MOISTURE ARE ON TRACK BASED ON LATEST
11-3.9 MICRON LOOP AND WITH CIGS UPSTREAM OF BKN100-120. BASED ON
CURRENT TEMPS IN THE 50S MOST SPOTS...AND A QUICK INCREASE OF CLOUDS
THIS MORNING...NAM OUTPUT WITH LOWER 70S MAY BE ON TO SOMETHING IN
THE WEST HALF. DID NOT GO THAT LOW OVER THE WEST JUST YET...BUT WENT
WELL BLO WHAT EVEN MIXING TO 925-900MB WOULD YIELD. BEST CHANCE FOR
WARMER TEMPS WILL BE OVER FAR NORTHERN TIER AND INTO THE EASTERN
INTERIOR AS THERE WILL BE MORE SUNSHINE THOSE AREAS INTO THE MORNING.
HIGHS BACK INTO THE 80S SEEM REASONABLE ESPECIALLY EASTERN INTERIOR.

KEYED ON LOCATION OF LOW-LEVEL JET FOR CONVECTION TONIGHT. AXIS OF
LOW-LEVEL JET IS MAINLY OVER WESTERN CWA TO START BUT THEN LIFTS
TOWARD LK SUPERIOR OVERNIGHT AS H85 LOW TRACKS NORTHEAST ACROSS
MINNESOTA INTO NORTHERN ONTARIO OVERNIGHT. MAXIMUM MOISTURE
ADVECTION H85-H7 GRADUALLY LIFTS NORTH ACROSS LK SUPERIOR AS WELL
OVERNIGHT. IN GENERAL SENSE...LARGER SCALE FORCING FOR ASCENT BETTER
TONIGHT AS SHORTWAVE AXIS WILL BE DRIFTING ACROSS WESTERN CWA. BEST
HEIGHT FALLS STAY WELL TO THE NORTH THOUGH. CONSENSUS FOR POPS
SUGGESTS GREATEST COVERAGE OVER KEWEENAW WHICH MAKES SENSE GIVEN
LOW-LEVEL JET POSITION. SIMILAR TO TODAY THOUGH...GIVEN BROAD WARM
AIR ADVECTION AND STEEP MID-LEVEL LAPSE RATES...CANNOT GO DRY
ANYWHERE TONIGHT AS THERE IS AT LEAST A SMALL CHANCE THAT SHRA/TSRA
COULD DEVELOP AT TIMES. EXPECT VERY MILD NIGHT WITH READINGS HAVING
TOUGH TIME FALLING BLO MID-UPR 60S ALONG LK SUPERIOR AND LK MICHIGAN
AND ONLY DROPPING INTO THE LOWER 60S INLAND. COULD ALSO BE BREEZY
ALONG MUCH OF LK SUPERIOR SHORE DUE TO DOWNSLOPE WARMING/MIXING WITH
THE STRONGER 950-850MB WINDS.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 516 AM EDT THU AUG 23 2012

MEDIUM RANGE MODELS DEPICT A PROGRESSIVE FLOW REGIME THRU THE LONG
TERM EVEN THOUGH PATTERN WILL AMPLIFY SOME EARLY NEXT WEEK. IT STILL
APPEARS THERE WILL BE 2 SHORTWAVES AFFECTING THE UPPER LAKES DURING
THE LONG TERM...ONE FRI AND THE SECOND DURING THE LATTER PORTION OF
THE WEEKEND. PCPN CHANCES WILL BE FOCUSED MAINLY AROUND THESE 2
SYSTEMS. PROGRESSIVE FLOW REGIME WILL LIMIT COOLING BEHIND EACH
SYSTEM...AND OVERALL...MAIN BAND OF WESTERLIES WILL BE SETTING UP N
OF THE AREA. THUS...TEMPS WILL BE ABOVE NORMAL THRU THIS FCST CYCLE.
THERE COULD BE ONE OR TWO VERY WARM/HOT DAYS AS WELL.

BEGINNING FRI...FIRST SHORTWAVE TROF WILL BE SHIFTING ACROSS THE
UPPER LAKES. WAVE WILL BE WEAKENING AS STRONGER SHORTWAVE MOVING
ACROSS SW CANADA BEGINS TO FORCE DOWNSTREAM HEIGHT RISES. SOME
CONVECTION MAY BE ONGOING FRI MORNING IN ASSOCIATION WITH 35-40KT
LOW-LEVEL JET TRANSLATING ACROSS THE AREA. WITH NOSE OF THE JET TO
THE N OF HERE...BEST PCPN POTENTIAL FRI MORNING WILL PROBABLY BE N
OF UPPER MI. MOVING INTO THE AFTN HRS...THE GFS LOOKS MUCH OVERDONE
WITH PCPN...LIKELY A RESULT OF ITS OVERLY MOIST LOW-LEVELS. FOR
EXAMPLE...IT HAS SFC DWPTS OF 65-70F INTO UPPER MI FRI...AND BY THE
WAY...YESTERDAYS 18Z GFS RUN VALID FOR 00Z LAST EVENING HAD SFC
DWPTS 10-20F TOO HIGH ACROSS PORTIONS OF THE PLAINS. THE DRIER
LOW-LEVELS ON THE NAM LOOK MUCH MORE REALISTIC GIVEN THE LARGE AREA
OF SEVERE TO EXCEPTIONAL DROUGHT UPSTREAM OVER THE CNTRL PLAINS TO
MID MISSISSIPPI VALLEY. EVEN WITH THE DRY LOW-LEVELS...NAM MLCAPE
INCREASES TO 1000-1500J/KG OVER THE W AND N FRI AFTN...PROVIDED MID
CLOUD COVER IS NOT TOO SIGNIFICANT TO LIMIT HEATING. IF CLOUDS ARE
NOT TOO WIDESPREAD...THE DRY LOW-LEVELS WILL CERTAINLY ALLOW FOR
STRONG WARMING DURING THE DAY. WITH MINIMAL CIN...THERE SHOULD BE AN
OPPORTUNITY FOR SCT CONVECTION TO DEVELOP WITH DAYTIME HEATING AS
THE WEAKENING SHORTWAVE TROF PASSES. WILL CONTINUE WITH CHC POPS. IF
LAKE BREEZE CAN MAKE A MOVE INLAND FROM LAKE SUPERIOR...AFTN
CONVECTION COVERAGE WILL BE HIGHEST ACROSS THE N. IN LEANING TOWARD
THE NAM...ALSO FAVORED ITS HIGHER MAX TEMP GUIDANCE WHICH IS MOSTLY
IN THE MID/UPPER 80S.

-SHRA/TSRA MAY LINGER INTO FRI EVENING. OTHERWISE...STRONGER
SHORTWAVE/MIDLEVEL LOW WILL BE ROLLING ACROSS SRN SASKATCHEWAN FRI
NIGHT. IN RESPONSE...LOW-LEVEL JET WILL INCREASE DOWNSTREAM INTO THE
UPPER MISSISSIPPI VALLEY. JET MAY BE FAR ENOUGH E LATE IN THE NIGHT
TO SUPPORT SOME CONVECTION OVER WRN LAKE SUPERIOR/WRN UPPER MI
OVERNIGHT.

IF ANY CONVECTION REACHES THE W LATE FRI NIGHT...IT SHOULD LIFT NE
OUT OF THE AREA SAT MORNING. SAT SHOULD THEN END UP A MOSTLY SUNNY
AND HOT DAY...ESPECIALLY FOR LATE AUG AS SHORTWAVE TRACKING THRU
SCNTRL CANADA IS STILL WELL TO THE WNW DURING THE DAY. STRONG
HEATING SHOULD OCCUR SAT AS LOW-LEVELS REMAIN DRY PER NAM FCST
SOUNDINGS. WITH THE DRY LOW LEVELS...FCST SOUNDINGS SUGGEST MIXING
HEIGHTS WILL REACH 700-750MB...WHICH YIELDS MAX TEMPS INTO THE
MID/UPPER 90S. FOR NOW...UPPER 80S/LWR 90S LOOK REASONABLE SINCE
WINDS ARE MORE SOUTHERLY RATHER THAN THE MORE IDEAL SW DIRECTION. IF
WINDS REMAIN STRONG ENOUGH TO PREVENT LAKE BREEZE OFF LAKE
SUPERIOR...DOWNSLOPE LOCATIONS NEAR THE LAKE MAY REACH THE MID 90S.
RECORD HIGH HERE AT THE OFFICE FOR SAT IS 88F. SHOULD BE ABLE TO
BREAK THAT. OBVIOUSLY...IT WILL BE COOLER TOWARD LAKE MICHIGAN WITH
SOUTHERLY WINDS.

SHORTWAVE NEAR LAKE WINNIPEG LATE SAT AFTN REACHES HUDSON BAY SUN. AS
WAS THE CASE YESTERDAY...THERE IS UNCERTAINTY IN WHETHER THAT SYSTEM
WILL PICK UP A SHORTWAVE OVER THE PLAINS. IF SO...PCPN CHANCES WILL
BE GREATLY INCREASED FOR THE UPPER LAKES SUN. RECENT MEDIUM RANGE
MODEL RUNS ARE TRENDING TOWARD THE ECMWF WHICH KEEPS THE 2 MORE
SEPARATED. AS A RESULT...NOTHING MORE THAN CHC POPS ARE WARRANTED
FOR SAT NIGHT/SUN AS MAJORTITY OF HEIGHT FALLS WITH MAIN SYSTEM PASS
WELL N OF THE FCST AREA...AND SHORTWAVE OVER THE PLAINS PASSES TOO
FAR S OF HERE TO BE MUCH OF A FACTOR.

AS ALLUDED TO ABOVE...PROGRESSIVE PATTERN WILL BEGIN TO AMPLIFY SOME
EARLY NEXT WEEK AS A MID/UPPER LEVEL RIDGE BUILDS ACROSS THE PLAINS
INTO SCNTRL CANADA. THE RIDGE WILL SHIFT E TO THE GREAT LAKES FOR
THE MIDDLE OF THE WEEK. THIS PATTERN WILL FAVOR DRY WEATHER FOR
UPPER MI DUE TO THE APPROACHING RIDGE. HOWEVER...DEVELOPING NW FLOW
MON COULD POSE SOME RISK OF ISOLD CONVECTION SINCE SUMMERTIME NW
FLOW OFTEN LENDS ITSELF TO ISOLD/SCT CONVECTION WITH ANY SUBTLE
SHORTWAVE. ALSO...SINCE FLOW REMAINS PROGRESSIVE...GFS/ECMWF SUGGEST
NEXT SHORTWAVE COULD BE APPROACHING LATE WED...PROVIDING NEXT CHC OF
PCPN. COOLEST DAYS WILL BE MON/TUE IN THE WAKE OF THE SHORTWAVE
TRACKING TO HUDSON BAY...BUT WITH SYSTEM LIFTING WELL TO THE
NE...THERE WON`T BE SIGNIFICANT CAA INTO THE UPPER LAKES...AND TEMPS
WILL LIKELY STILL REMAIN ABOVE NORMAL. SOME WARMING EXPECTED FOR
WED.
&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 745 AM EDT THU AUG 23 2012

SHRA/TSRA HAVE EXPANDED THIS MORNING JUST WEST OF UPR MICHIGAN AND
THESE WILL AFFECT ALL TAF SITES THROUGH AT LEAST EARLY AFTN. FOR MOST
PART EXPECT VFR CONDITIONS THOUGH THERE COULD BE BRIEF SUB VFR VSBY
IN THE HEAVIER SHRA/TSRA OVER WESTERN UPR MICHIGAN THIS MORNING. LULL
MAY FORM LATER TODAY BEFORE MORE SHRA/TSRA DEVELOP AGAIN TONIGHT.
BEST CHANCE FOR TSRA TONIGHT WILL BE AT IWD AND CMX. HAVE INCLUDED A
MENTION OF VICINITY THUNDER /VCTS/ IN THOSE TAFS.

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 516 AM EDT THU AUG 23 2012

EXPECT SOUTHEASTERLY WINDS UNDER 20KT TODAY. AS A LOW-LEVEL JET
DEVELOPS OVER THE AREA TONIGHT...S WINDS WILL INCREASE OVER ERN LAKE
SUPERIOR. GUSTS MAY REACH 25-30KT FROM AROUND GRAND MARAIS
NORTHWARD. AS IS TYPICALY THE CASE...THE S WINDS WILL BE LIGHTER
OVER WRN LAKE SUPERIOR. SOUTHERLY WINDS WILL DIMINISH SOME FRI...
THEN PICK UP AGAIN FRI NIGHT/SAT WITH GUSTS UP AROUND 20KT AS A LOW
PRES TROF APPROACHES FROM THE W. THE TROF WILL CROSS LAKE SUPERIOR
SUN. WINDS MON SHOULD BE UNDER 15KT AS SFC HIGH PRES BUILDS INTO THE
UPPER LAKES.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

UPDATE...JLA
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...JLA
MARINE...ROLFSON

AREA FORECAST DISCUSSION...UPDATED

NWS DULUTH MN

1023 AM CDT THU AUG 23 2012

.UPDATE...GIVEN UNCERTAINTY IN FORCING MECHANISMS AND INCREASINGLY
UNSTABLE NATURE OF ATMOSPHERE...TOUGH TO CHANGE MUCH IN EXISTING
FCST. INITIAL SHORTWAVE TROF HAS MOVED INTO ERN CWA. THIS HAS
DRAGGED MAIN PWS PLUME FROM PINE COUNTY TO WRN BAYFIELD COUNTY.
INCREASED POPS OVER NWRN WISC THIS MORNING AS LATEST 88D SHOWS NEW
DEVELOPMENT OVER SRN PINE/BURNETT COUNTIES. RUC13 ANALYSIS SHOWS
FAIRLY WELL DEFINED WIND SHEAR AXIS FROM ARROWHEAD WEST TOWARDS NE
NODAK. NEW CELLS HAVE DEVELOPED OVER RANGE AND ARROWHEAD AND HAVE
RAISED POPS FOR THIS AREA TODAY. GENERAL IDEA IS THAT FIRST
SHORTWAVE WILL ADVECT EAST OF CWA BY AFTN. A DECREASE IN POPS OVER
SERN WISC ZONES WITH BETTER INSTABILITY TAXIS REALIGNING FROM BRD
LAKES VICINITY NORTHEAST INTO ARROWHEAD/RANGE. LOWERED MAX TEMPS A
FEW DEGREES OVER NWRN WISC DUE TO CLOUD COVER/PRECIP.

.PREV DISCUSSION... /ISSUED 635 AM CDT THU AUG 23 2012/

AVIATION...12Z TAFS

WAA AIDING IN SHOWER AND THUNDERSTORM DEVELOPMENT THIS MORNING. WE
INCLUDED THEM IN THE KDLH/KHYR/KHIB TAFS THROUGH 15Z OR 16Z...AND
KBRD THROUGH 14Z. WE PUT A BREAK IN THE TAFS...THEN PUT
THUNDERSTORMS BACK IN A FRONT/TROUGH MOVES INTO THE NORTHLAND
LATER THIS AFTERNOON AND EVENING. MVFR CONDITIONS WILL BE POSSIBLE
TODAY AND THIS EVENING IN THE STRONGER STORMS. FOG WILL BE
POSSIBLE TONIGHT AS THE STORMS SHIFT EAST...AND SKIES CLEAR AND
WINDS ARE EXPECTED TO BE LIGHT.

PREV DISCUSSION... /ISSUED 337 AM CDT THU AUG 23 2012/

SHORT TERM...LATEST NOAM WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL
SHORTWAVE CURRENTLY OVER MN AND WRN WI. SCTD SHOWERS AND STORMS
HAVE DEVELOPED IN A BAND ACROSS OUR SRN ZONES EARLY THIS
MORNING...GENERALLY AFFECTING AREAS SOUTH OF THE TWIN PORTS
INCLUDING THE SAINT CROIX RIVER VALLEY. THIS ACTIVITY WILL
CONTINUE TO SPREAD NWD ACROSS THE REST OF OUR CWA TODAY...WITH
SOME REDEVELOPMENT ALSO EXPECTED FARTHER SOUTH AND WEST. HOWEVER
DUE TO DISAGREEMENTS BETWEEN THE NWP MODELS...HAVE KEPT POPS IN
THE HIGH CHANCE RANGE WITH MENTION OF SCTD SHOWERS AND STORMS.
PRECIP CHANCES WILL INCREASE TO LIKELY TONIGHT AS TROUGH AXIS
MOVES OVER THE NORTHLAND AND THE CONVECTION BECOMES MORE
ORGANIZED...MAINLY ALONG AND EAST OF A LINE FROM ELY TO CLOQUET TO
PINE CITY MN. THE SHOWERS AND STORMS WILL GRADUALLY MOVE OFF TO
THE EAST OVERNIGHT TONIGHT AND DIMINISH ACROSS OUR ERN ZONES
DURING THE DAY ON FRIDAY.

THE NAM12 CONTINUES TO SHOW MODERATE INSTABILITY DEVELOPING THIS
AFTERNOON AND EVENING IN ASSOC WITH THIS DISTURBANCE...ALTHOUGH
DAYTIME HEATING WILL BE A KEY FACTOR IF CLOUD COVER BECOMES MORE
WIDESPREAD. WITH MUCAPES RANGING FROM 1500-3000 J/KG AND WITH WEAK
TO MODERATE SHEAR POSSIBLE...ISOLD STRONG/SEVERE STORMS ARE
POSSIBLE AS OUTLINED IN SWODY1 ISSUED BY THE SPC. CONDITIONS WILL
BE WARM AND HUMID ON FRIDAY WITH HIGHS IN THE MID 80S AS SKIES
CLEAR OUT ALLOWING FOR APPRECIABLE DAYTIME HEATING.

LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY.
AN UPPER LEVEL LOW WILL MOVE TOWARD SOUTHEAST SASKATCHEWAN BY 12Z
SAT...THEN CONTINUE EAST THEN NORTHEAST AND MOVE INTO NORTHERN
ONTARIO BY 12Z SUNDAY. ALTHOUGH THE STRONGEST FORCING REMAINS WELL
NORTH...A FRONTAL BOUNDARY WILL SLOWLY MOVE THROUGH THE CWA
SATURDAY THROUGH SUNDAY. WE HAVE A SMALL CHANCE FOR SHOWERS/STORMS
FRIDAY NIGHT WITH PERSISTENT WEAK WARM AIR/MOISTURE ADVECTION
ACROSS THE CWA. THE FRONT WILL MOVE SLOWLY THROUGH THE CWA
SATURDAY INTO SUNDAY AND WE HAVE HIGHER POPS DUE TO STRONGER
FORCING WITH THE FRONT.

MODELS IN DECENT AGREEMENT BUILDING HIGH PRESSURE INTO THE REGION
MONDAY WITH A DRY DAY EXPECTED.

THE ECMWF IS A BIT OF AN OUTLIER TUESDAY MOVING IT`S UPPER RIDGE
FURTHER EAST OVER MINNESOTA WITH LOW PRESSURE ON IT`S HEELS...WHILE
THE GEM AND GFS KEEP HIGH PRESSURE ALOFT CENTERED OVER CO...WITH
RIDGING EXTENDING NORTH. THE ECMWF HAS BEEN CONSISTENT OVER IT`S
PAST FEW RUNS...AND THE GFS 12Z 22ND RUN WAS CLOSER TO THE CURRENT
ECMWF...BOTH THE 18Z AND 00Z GFS RUNS ARE IN LINE WITH THE LATEST
GEM. THE RESULT OF THE DIFFERENCES WOULD BE BRINGING IN PRECIP
FASTER IF WE FOLLOWED THE ECMWF. HOWEVER...WE WILL GO WITH
PERSISTENCE AND THE GEM/GFS AND CONTINUE A DRY FORECAST INTO TUESDAY
NIGHT...BEFORE ADDING POPS WEDNESDAY.

HIGHS THROUGH THE PERIOD WILL GENERALLY RANGE FROM THE MID SEVENTIES
TO LOWER EIGHTIES.

.POINT TEMPS/POPS...
DLH 78 62 83 65 / 50 60 10 20
INL 81 59 83 62 / 50 40 10 50
BRD 82 63 86 68 / 50 50 10 30
HYR 81 64 86 64 / 60 60 30 20
ASX 80 64 84 64 / 50 60 30 20

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&

SHORT TERM...CANNON

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

1029 AM EDT THU AUG 23 2012

.SYNOPSIS...
UPPER LEVEL DISTURBANCES AND A STALLED FRONT OFFSHORE WILL KEEP THE
WEATHER UNSETTLED THROUGH FRIDAY. SOME SLIGHTLY DRIER AIR WILL WORK
INTO THE AREA OVER THE WEEKEND. EARLY NEXT WEEK...ALL EYES WILL BE
FOCUSED ON TROPICAL CYCLONE ISAAC TO OUR SOUTH AND ITS EVENTUAL
TRACK. THE RISK FOR WET WEATHER WILL RETURN DURING TUESDAY.

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM THURSDAY...THE FRONT IS EASILY DISCERNIBLE ON MORNING
VISIBLE SATELLITE IMAGERY AND EXTENDS FROM ABOUT 15 MILES EAST OF
GEORGETOWN TO 10 MILES NORTH OF THE FRYING PAN SHOALS TOWER TO ABOUT
70 MILES EAST OF WRIGHTSVILLE BEACH. THE LIGHT NE FLOW COVERING THE
EASTERN CAROLINAS IS NOT A SIGNIFICANTLY DIFFERENT AIRMASS THAN THAT
FOUND SOUTH OF THE FRONT...AND SHOULD DO NOTHING TO PREVENT SHOWERS
AND EMBEDDED THUNDERSTORMS FROM DEVELOPING LATER TODAY.

A STREAM OF HIGH PRECIPITABLE WATER VALUES EXTENDS FROM THE EASTERN
GULF OF MEXICO NORTHEAST ALONG THE CAROLINA COAST. BLENDED TOTAL
PRECIPITABLE WATER IMAGERY FROM SATELLITE AGREES WITH MODEL ANALYSES
SHOWING 1.80 TO 2.00 INCH PRECIPITABLE WATER OVERHEAD. MID-LEVEL
TEMPERATURES FROM THE 12Z CHS AND MHX SOUNDINGS WERE SURPRISINGLY
COOL...-9 C AT 500 MB...AND LAPSE RATES WERE SLIGHTLY STEEPER THAN
MOIST-ADIABATIC UP THROUGH 300 MB...ALL INDICATIVE OF AN AIRMASS
THAT IS SUITABLE FOR CONVECTION. IT WILL ONLY TAKE TEMPERATURES
REACHING THE LOWER 80S TO IGNITE ANOTHER ROUND OF SCATTERED SHOWERS
AND EMBEDDED THUNDERSTORMS.

THE LATEST THREE HRRR RUNS INDICATE THAT MUCH LIKE YESTERDAY WE CAN
EXPECT THE GREATEST CONCENTRATION OF CONVECTION WITHIN 30-40 MILES
OF THE COAST THIS AFTERNOON. COMPUTED CELL MOTION FROM THE 12Z
SOUNDINGS IS LESS THAN 5 KNOTS...AND BOUNDARY INTERACTIONS WILL MOST
LIKELY OVERWHELM THAT DRIFT AND CREATE VARIABLE AND ERRATIC
EFFECTIVE STORM MOTION. WITH SUCH HIGH PRECIPITABLE WATER VALUES WE
EXPECT LOCALLY HEAVY RAIN TO OCCUR WITH MINOR FLOODING POSSIBLE.

HIGHS SHOULD REACH THE LOWER 80S WITH PERHAPS A FEW MID 80S POSSIBLE
OUT WEST OF FLORENCE.

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...MID LEVEL LOW OR REALLY A WEAKNESS WILL
SLOWLY LIFT OUT TO THE NORTHEAST AS A WEAK RIDGE BUILDS ACROSS THE
TENNESSEE VALLEY. HIGH PRESSURE WILL BUILD IN FROM THE NORTHEAST
WITH THE AXIS TO THE WEST ALONG THE APPALACHIANS. THE GFS HAS TRENDED
A LITTLE WETTER AND POPS ARE INCLUDED FOR BOTH FRIDAY AND TO A
LESSER EXTENT SATURDAY. CONTINUED THE RECENT TREND OF GOING ABOVE
THE WARMEST GUIDANCE FOR TEMPERATURES.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 3 AM THURSDAY...FORECAST AREA WILL BE IN A VERY NARROW
WEAKNESS OF MID LEVEL TROUGHING INITIALLY. THIS AREA WILL SLOWLY
DEEPEN AS A SHORTWAVE RIDES ACROSS THE GREAT LAKES AND EVENTUALLY THE
NORTHEAST. THIS WEAKNESS WILL BE THE KEY TO THE EVENTUAL FORECAST OF
ISAAC. AT THE SURFACE...HIGH PRESSURE WILL PREVAIL UNTIL LATE IN THE
PERIOD WHEN CLOUDS AND RAIN INCREASE FROM WHAT REMAINS OF ISAAC. THE
TREND HAS BEEN TO INCREASE CLOUDS AND POPS FOR LATE IN THE PERIOD
WITH THE USUAL DISCLAIMER THAT THE TRACK COULD CHANGE AND AT THIS
POINT THE EMPHASIS WITH THE CLOUDS AND RAIN ARE WITH THE REMNANTS OF
THE SYSTEM. OTHERWISE...SUNDAY SHOULD REMAIN DRY WITH ONLY SLIGHT
CHANCE POPS FOR MONDAY VIA THE SEA BREEZE. NO CHANGES TO THE
TEMPERATURE FORECAST WHICH HOVERS AROUND CLIMATOLOGY FOR HIGHS AND
SLIGHTLY BELOW AT LEAST INITIALLY FOR THE LOWS. THE AFOREMENTIONED
INCREASE IN MOISTURE NARROWS THE DIURNAL RANGE LATE IN THE PERIOD.

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 12Z...A STATIONARY FRONT IS LOCATED OFFSHORE WITH NE FLOW IN
THE LOW-LEVELS TO THE WEST OF THE FRONT. WEAK CAA HAS RESULTED IN
A LOW LVL INVERSION WHICH HAS TRAPPED MOISTURE FROM YESTERDAYS RAINS
IN THE 100-300 FOOT RANGE...MAINLY AT THE COAST TERMS AND JUST
INLAND. DUE TO THE LOW CIGS VSBYS HAVE ALSO DROPPED INTO THE
LIFR/IFR RANGE AT CRE/MYR AND MVFR RANGE AT ILM. AT FLO THIS MORNING
THE LOW LVL INVERSION IS LESS PRONOUNCED AND CIGS ARE GENERALLY
MVFR. LBT IS MORE ON THE EDGE OF ALL THE LOW CLOUDINESS. ISOLATED
SHOWERS ARE PERSISTING SE OF THE COAST TERMS.

THE LOW LVL INVERSION SHOULD REMAIN INTACT AT LEAST EARLY THIS
MORNING AS LONG AS NE FLOW CONTINUES. IT MAY BE AS LATE AS 15-16Z AT
CRE/MYR BEFORE IFR CIGS LIFT TO MVFR OR GREATER. TEMPO MVFR CIGS
WILL BE LIKELY AFTERWARD AS CIGS LIFT AND SHRA BEGINS TO DEVELOP.
THE COAST TERMS WILL BE MOST LIKELY TO EXPERIENCE SHRA/ISOLATED TS
TODAY BUT CONFIDENCE OF ANY TIMING IS LOW. WILL INDICATE TEMPO MVFR
CONDITIONS ATTM AND AMEND AS NECESSARY FOR IFR/TS.

THERE IS LESS CHANCE OF DENSE FOG AND STRATUS OVERNIGHT. A MORE
SIGNIFICANT SHORT WAVE WILL BE PASSING WHICH SHOULD PROVIDE COPIOUS
AMOUNTS OF CLOUD COVER...AS WELL AS LIGHT RAIN AT FLO/LBT AND
MODERATE TO HEAVY SHOWERS AT THE COAST TERMS.

EXTENDED OUTLOOK...ISOLATED SHRA/TS FRIDAY...SATURDAY AND MONDAY.
SCT SHRA/TS SUNDAY.

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM THURSDAY...THE FRONT HAS SLID SOUTH THROUGH VIRTUALLY
ALL OF OUR FORECAST AREA THIS MORNING...EXTENDING FROM APPROXIMATELY
15 MILES EAST OF GEORGETOWN TO 10 MILES NORTH OF THE FRYING PAN
SHOALS TOWER TO ABOUT 70 MILES EAST OF WRIGHTSVILLE BEACH. NORTHEAST
WINDS 10-15 KT ON THE NORTH SIDE OF THE BOUNDARY CONTRAST WITH LIGHT
AND VARIABLE WINDS TO THE SOUTH. EARLIER SHOWERS HAVE LARGELY
DISSIPATED WITHIN 20 MILES OF SHORE EXCEPT IN THE VICINITY OF THE
FRONT NEAR FRYING PAN SHOALS.

FOR THE REMAINDER OF TODAY THE LITTLE NE SURGE BEHIND THE SURFACE
FRONT SHOULD WEAKEN THROUGH THE AFTERNOON HOURS WITH WIND SPEEDS
FALLING TO 10 KNOTS OR LESS. WE ANTICIPATE AN INCREASE IN THE
COVERAGE OF SLOW-MOVING SHOWERS AND EMBEDDED THUNDERSTORMS THIS
AFTERNOON ALONG THE COAST...SOME OF WHICH WILL DRIFT OFFSHORE AND
AFFECT THE COASTAL WATERS. WITH VERY LIGHT WINDS AND UNSTABLE AIR
THE POTENTIAL FOR WATERSPOUT DEVELOPMENT REMAINS ELEVATED.

SEAS RANGE FROM 2 FT TO AROUND 3 FT OUT AT THE FRYING PAN SHOALS
BUOY. LITTLE CHANGE IS EXPECTED THROUGH TODAY AND TONIGHT.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...BENIGN CONDITIONS WILL CONTINUE ACROSS THE
WATERS THROUGH THE PERIOD AS A VERY WEAK SURFACE PRESSURE PATTERN
RESIDES ACROSS THE WATERS. A WEAK NORTHEASTERLY FLOW OF LESS THAN
TEN KNOTS BOTH FRIDAY AND SATURDAY. SWAN SEAS SHOW 2-4 FEET AND THE
POSSIBILITY OF SOME FIVE FOOTERS VERY LATE IN THE PERIOD.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...EXPECT A NORTHEASTERLY FLOW THROUGH MOST OF
THE PERIOD AS SURFACE HIGH PRESSURE...ALIGNED ALONG THE SPINE OF THE
APPALACHIANS IS THE MAIN PLAYER. THE FLOW SHOULD VEER SLIGHTLY LATE
MONDAY AS THE HIGH BREAKS DOWN. SPEEDS GO FROM AROUND TEN KNOTS
INITIALLY TO 10-15 LATE. SEAS INCREASE FROM 2-4 FEET INITIALLY TO
3-5 FEET LATE AS SWELL FROM THE SOUTHEAST INCREASES.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...MRR

AREA FORECAST DISCUSSION

NWS RALEIGH NC

735 AM EDT THU AUG 23 2012

.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL MOVE SLOWLY EAST OVER THE AREA TODAY.
SURFACE HIGH PRESSURE WILL STRENGTHEN OVER THE CAROLINAS AND THE
MID-ATLANTIC FRIDAY AND PERSIST INTO THE WEEKEND.

.NEAR TERM /THROUGH FRIDAY/...
AS OF 310 AM THURSDAY...

PERSISTENCE SHOULD BE APPROPRIATE FOR HIGHS AGAIN TODAY...LEADING TO
LOW TO MID 80S DEPENDING ON WHERE CLOUDS MID/HIGH CLOUDS THIN THE
MOST.

FRIDAY...
DRIER AIR LOW LEVEL AIR IS FORECAST TO FINALLY MAKE ITS WAY ACROSS
MUCH OF CENTRAL NC FRIDAY...AS HIGH PRESSURE RIDGE SETS UP ALONG THE
EAST COAST. OPERATIONAL MODELS WOULD SUGGEST AT LEAST ISOLATED
SHOWERS/STORMS MAY BE POSSIBLE FROM THE COASTAL PLAIN TO THE
SANDHILLS. THE UPPER LEVEL TROUGH OR WEAK LOW WILL BE OVERHEAD ON
FRIDAY WITH SOME DISTURBANCES POSSIBLY ROTATING ACROSS SC AND NC.
IF DEWPOINTS DO NOT FALL INTO THE LOWER 60S...THEN BETTER....ALBEIT
WEAK...INSTABILITY MAY DEVELOP OVER THE PIEDMONT AND SLIGHT CHANCES
POPS COULD BE WARRANTED OVER THE ENTIRE AREA. QUITE A BIT MORE
SUNSHINE IS EXPECTED FRIDAY AFTERNOON AND HIGHS SHOULD BE 2-3
DEGREES WARMER REACHING THE MID TO UPPER 80S.

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 145 AM THURSDAY...

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 240 AM THURSDAY...

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 735 AM THURSDAY...

MVFR VSBYS ARE MOSTLY FOCUSED OVER THE CENTRAL AND WESTERN
PIEDMONT...IMPACTING TERMINALS FROM KRWI TO KINT. HOWEVER...VSBYS
WILL IMPROVE QUICKLY AFTER 12Z...WITH VFR CONDITIONS AND CLOUD BASES
GENERALLY ABOVE 3500 FT THIS AFTERNOON. AN UPPER LEVEL TROUGH
SLOWLY CROSSING NC FROM THE WEST WILL HELP TO TRIGGER SCATTERED
SHOWERS THIS AFTERNOON AND EVENING...WITH THE HIGHEST PROBABILITIES
SEEMING TO BE AROUND KFAY.

SHOWERS/STORMS ARE DIMINISH BY LATE THIS EVENING....ALTHOUGH MODELS
INDICATE AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS EASTERN NC
AFTER MIDNIGHT...WHICH COULD CONTINUE THE THREAT OF SHOWERS INTO THE
EARLY MORNING HOURS. OTHERWISE...MVFR VSBYS SHOULD ONCE AGAIN
DEVELOP BY 09Z.

OUTLOOK...
HIGH PRESSURE WILL SETTLE OVER THE EASTERN US BY THIS WEEKEND.
OTHER THAN THE POTENTIAL FOR EARLY MORNING FOG OR STRATUS...MAINLY
SUNDAY MORNING...VFR CONDITIONS GENERALLY EXPECTED TO PREVAIL.

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

SYNOPSIS...WSS
NEAR TERM...SMITH
SHORT TERM...HARTFIELD
LONG TERM...HARTFIELD
AVIATION...SMITH

AREA FORECAST DISCUSSION

NWS CHARLESTON WV

616 AM EDT THU AUG 23 2012

.NEAR TERM /THROUGH TONIGHT/...LATEST RAP SHOWS UPPER TROUGH AXIS
HAS FINALLY PASSED TO THE EAST...WITH ONLY A FEW SPRINKLES STILL
REMAINING OVER SOUTHERN POCAHONTAS COUNTY. HIGH PRESSURE WILL
CONTINUE AT THE SURFACE...WITH A MAINLY WARM AND SUNNY DAY AHEAD.
MODELS SHOWING JUST ENOUGH MOISTURE THIS AFTERNOON...AND SOME WEAK
BOUNDARY LAYER CONVERGENCE/UPSLOPE FLOW IN THE WV MOUNTAINS...SO
ADDED SOME SCATTERED POPS...AND EXPANDED THE ISOLATED POPS A
LITTLE IN OUR EXTREME EASTERN ZONES. AS THE SLOW WARMING TREND
CONTINUES...EXPECT TODAY TO BE A DEGREE OR TWO WARMER THAN
YESTERDAY. PREVIOUS FORECAST FOR TODAYS HIGHS LOOKED GOOD AND MADE
NO SIGNIFICANT CHANGES THERE. ONLY SMALL ADJUSTMENTS MADE TO
TONIGHT LOWS AS WELL BY BLENDING IN THE MET WHICH HAS BEEN
OUTPERFORMING THE MAV FOR LOWS RECENTLY. THIS RESULTED IN A BIT
WARMER FORECAST IN THE NORTHERN MOUNTAIN ZONES.

BUT THE MAIN THEME CONTINUES TO THE THE WARM AFTERNOONS. DID
INCREASE MAXIMUM TEMPERATURES A FEW DEGREES IN SOME OF THE WESTERN
RIVER VALLEYS FOR FRIDAY AND SATURDAY...WITH THE DRY GROUND.

ANY WEAK UPSLOPE FLOW AT 925/850 MB SEEMS TO BE GONE BY SUNDAY. SO
MOST POPS AOB 14 PERCENT FOR SUNDAY.

ROLLED WITH HPC TEMPERATURES THROUGH THE PERIOD.

.AVIATION /10Z THURSDAY THROUGH MONDAY/...
IFR TO LIFR FOG CURRENTLY IMPACTING SEVERAL TAF SITES...WITH OTHERS
STILL MVFR. EXPECT LIKE YESTERDAY MORNING...WILL GET A QUICK DROP
AT THE MVFR SITES INTO AT LEAST IFR JUST BEFORE SUNRISE...BEFORE
ALL SITES IMPROVE TO VFR FOR THE REST OF THE DAY WITH LIGHT WINDS
AT THE SURFACE AND ALOFT.

THERE SHOULD AGAIN BE SOME ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS OVER MOUNTAINS THIS AFTERNOON. EXPECTING A REPEAT OF
FOG AGAIN TONIGHT INTO EARLY FRIDAY MORNING...WITH DENSE FOG
SHOWING UP AT KEKN BY 09Z AND AT OTHER FOG PRONE SITES BY 10Z-11Z.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING AND EXTENT OF FOG COULD VARY.

AFTER 12Z FRIDAY...
NO SIGNIFICANT IFR EXPECTED.

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

$$
SYNOPSIS...KTB/MZ
NEAR TERM...MZ
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...MZ

AREA FORECAST DISCUSSION...UPDATED

NWS NORMAN OK

905 AM CDT THU AUG 23 2012

.UPDATE...
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP AND MOVE ACROSS
WESTERN PORTIONS OF THE FA THIS MORNING. THE ACTIVITY IS EXPECTED
TO WEAKEN LATER THIS MORNING/EARLY AFTERNOON. HAVE ADJUSTED POPS
TO ACCOUNT FOR CURRENT ACTIVITY. SKIES WILL BE CLOUDY/MOSTLY
CLOUDY ACROSS MUCH OF THE AREA THIS MORNING. WILL SEND UPDATES
SHORTLY.

MAXWELL
&&

.PREV DISCUSSION... /ISSUED 645 AM CDT THU AUG 23 2012/

AVIATION...
SCATTERED SHRA/TSRA HAVE DEVELOPED EARLY THIS MORNING AS AN UPPER
DISTURBANCE MOVED INTO OKLAHOMA. THIS ACTIVITY WILL LIKELY LINGER
INTO THE EARLY AFTERNOON...WITH ISOLATED TSRA POSSIBLE INTO PARTS
OF NORTHERN AND CENTRAL OKLAHOMA BY LATE AFTERNOON. BRIEF MVFR
VSBYS WILL BE POSSIBLE WITH THESE STORMS...ESPECIALLY AT KCSM AND
KHBR...WITH LOWER PROBABILITIES AT KOKC...KOUN...AND KLAW. EXPECT
MORE WIDESPREAD SHRA WITH EMBEDDED TSRA ACROSS PORTIONS OF
NORTHERN AND WESTERN OKLAHOMA THIS EVENING AND
OVERNIGHT...SPREADING INTO CENTRAL OK BY 12Z FRIDAY. WILL INCLUDE
PROB30 GROUPS AT MOST SITES AS EXACT TIMING AND COVERAGE OF
SHRA/TSRA REMAINS IN QUESTION. OUTSIDE OF OCCASIONALSTORMS...GUSTY
SOUTH TO SOUTHWEST WINDS ARE EXPECTED THIS AFTERNOON THROUGH THIS
EVENING.

PREV DISCUSSION... /ISSUED 342 AM CDT THU AUG 23 2012/

DISCUSSION...
WIDESPREAD MID AND HIGH CLOUDS OVERSPREAD MUCH OF THE REGION AS A
WEAK UPPER DISTURBANCE MOVES SOUTHWARD THROUGH THE FLOW. AS THIS
CONTINUE TO MOVE SOUTHWARD ACROSS THE REGION...MODEST MID LEVEL
ASCENT MAY ALLOW FOR VERY ISOLATED SHOWERS AND PERHAPS A STORM OR
TWO. RECENT RUNS OF THE HRRR DEPICT A LARGE AREA OF SHOWER AND
THUNDERSTORM ACTIVITY DEVELOPING BY 10Z TO 11Z OVER WESTERN
OKLAHOMA AND NORTH TEXAS. CONFIDENCE IS LOW IN THIS SCENARIO AND
WILL MAINTAIN ONLY SLIGHT CHANCE POPS THROUGH 12Z THIS MORNING.
SHOWERS AND STORMS SHOULD DEVELOP THIS MORNING OVER WESTERN
OKLAHOMA AND PERSIST INTO TONIGHT...SPREADING EASTWARD WITH TIME.
EXPECT THE BEST CHANCES TO REMAIN OVER NORTHWEST OKLAHOMA. AS
SUCH...DAYTIME MAX TEMPS WILL BE A FEW DEGREES COOLER ACROSS
WESTERN OKLAHOMA AND WESTERN NORTH TEXAS.

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 69 86 72 / 20 40 50 60
HOBART OK 89 68 89 70 / 30 40 50 50
WICHITA FALLS TX 94 70 91 74 / 20 30 30 30
GAGE OK 89 68 90 69 / 40 50 50 60
PONCA CITY OK 92 69 85 71 / 10 50 50 60
DURANT OK 90 68 89 73 / 10 10 20 40

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

25/06

AREA FORECAST DISCUSSION

NWS NORMAN OK

645 AM CDT THU AUG 23 2012

.AVIATION...
SCATTERED SHRA/TSRA HAVE DEVELOPED EARLY THIS MORNING AS AN UPPER
DISTURBANCE MOVED INTO OKLAHOMA. THIS ACTIVITY WILL LIKELY LINGER
INTO THE EARLY AFTERNOON...WITH ISOLATED TSRA POSSIBLE INTO PARTS
OF NORTHERN AND CENTRAL OKLAHOMA BY LATE AFTERNOON. BRIEF MVFR
VSBYS WILL BE POSSIBLE WITH THESE STORMS...ESPECIALLY AT KCSM AND
KHBR...WITH LOWER PROBABILITIES AT KOKC...KOUN...AND KLAW. EXPECT
MORE WIDESPREAD SHRA WITH EMBEDDED TSRA ACROSS PORTIONS OF
NORTHERN AND WESTERN OKLAHOMA THIS EVENING AND
OVERNIGHT...SPREADING INTO CENTRAL OK BY 12Z FRIDAY. WILL INCLUDE
PROB30 GROUPS AT MOST SITES AS EXACT TIMING AND COVERAGE OF
SHRA/TSRA REMAINS IN QUESTION. OUTSIDE OF OCCASIONALSTORMS...GUSTY
SOUTH TO SOUTHWEST WINDS ARE EXPECTED THIS AFTERNOON THROUGH THIS
EVENING.

.PREV DISCUSSION... /ISSUED 342 AM CDT THU AUG 23 2012/

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

30/84/84

AREA FORECAST DISCUSSION...UPDATED

NWS ABERDEEN SD

1020 AM CDT THU AUG 23 2012

.UPDATE...
PRECIPITATION HAS PUSHED OFF TO THE EAST OF THE REGION...SO HAVE
REMOVED ALL POPS FROM THE FORECAST FOR TODAY. NO CHANGES MADE TO
WINDS OR TEMPERATURES AT THIS TIME.

&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH SATURDAY
SHOWERS AND THUNDERSTORMS CONTINUE TO MOVE EASTWARD ACROSS THE
EASTERN PORTION OF THE CWA...SCATTERED IN VARIETY. THINGS ARE
SHIFTING EAST WITH THE MOVEMENT OF THE LOW LEVEL JET. EXPECTING
THIS TREND TO CONTINUE OVER THE NEXT SEVERAL HOURS WITH ACTIVITY
PUSHING EAST INTO MN LATER THIS MORNING. ANY REDEVELOPMENT LATER
THIS AFTERNOON IS LOOKING LESS LIKELY OVER OUR AREA WITH THE FRONT
PUSHING EASTWARD AT A GOOD CLIP. EXPECT MOST ACTIVITY LATER TODAY
TO BE ACROSS MN INTO SOUTHEAST SD AND PORTIONS OF IA AND NE. ONE
THING TO WATCH THIS MORNING THOUGH IS ANOTHER WEAK DISTURBANCE OFF
TO THE WEST OVER WY. WATER VAPOR SHOWS THIS AND THERE IS AN ACCAS
FIELD ACROSS NORTHEAST WY AND SOUTHWEST SD. HRRR IS ACTUALLY
SHOWING A FEW SPOTTY SPRINKLES/LIGHT SHOWERS ADVANCING ACROSS
WESTERN AND CENTRAL SD THROUGH THE MORNING. FOR NOW HAVE NOT
INCLUDED ANYTHING IN THE FORECAST AS OBS TO THE WEST INDICATE VERY
HIGH CEILINGS. THIS WILL NEED TO BE WATCHED THOUGH FOR POTENTIAL
OF ISO SHOWERS OR SPRINKLES ACROSS THE SOUTHWEST CWA LATER THIS
MORNING.

.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

A FEW LIGHT SHOWERS AND POSSIBLY A RUMBLE OF THUNDER REMAIN AROUND
THE KATY TERMINAL WITH THE TAF ISSUANCE...HOWEVER THESE WILL
CONTINUE TO PROCEED EAST WITH LIMITED COVERAGE/INTENSITY. WINDS
OUT OF THE NORTH WILL SHIFT AROUND TO SOUTHERLY TONIGHT. VFR
CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD.

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

$$
UPDATE...PARKIN
SHORT TERM...TMT
LONG TERM...CONNELLY
AVIATION...CONNELLY

WEATHER.GOV/ABERDEEN

AREA FORECAST DISCUSSION

NWS ABERDEEN SD

625 AM CDT THU AUG 23 2012

.UPDATE...

SEE UPDATED AVIATION DISCUSSION BELOW.

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY

AN UPPER RIDGE WILL BUILD OVER THE WESTERN CONUS DURING THE
PERIOD...WITH A VERY GRADUAL/SLOW EASTWARD PROGRESSION. THE
RESULTING STABLE CONDITIONS AND THE REDEVELOPMENT OF AN ELEVATED
MIXED LAYER WITH H7 TEMPERATURES WARMING FROM AROUND +5C TO
UPWARDS OF +14C TRANSLATES INTO AN EXTENDED DRY PERIOD WITH
TEMPERATURE GRADUAL WARMING TO ABOVE NORMAL FOR THE FIRST HALF OF
NEXT WEEK.

.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

$$
UPDATE...CONNELLY
SHORT TERM...TMT
LONG TERM...CONNELLY
AVIATION...CONNELLY

WEATHER.GOV/ABERDEEN

AREA FORECAST DISCUSSION...UPDATED

NWS AMARILLO TX

637 AM CDT THU AUG 23 2012

.AVIATION...
FOR THE 12Z TAFS...VFR CONDITIONS ARE EXPECTED OUTSIDE OF TSRA.

PRIMARY CONCERN IS POTENTIAL FOR TSRA THIS AFTERNOON AND EVENING.
HIGHEST POTENTIAL APPEARS TO BE AT KDHT AND KGUY. DELAYED START OF
VCTS AT KDHT TO 01Z-05Z AND INSERTED VCTS REMARKS AT KGUY 23Z-04Z.
HAVE SOMEWHAT LOW CONFIDENCE ON TIMING. THERE IS A POSSIBILITY KAMA
COULD BE IMPACTED 23Z-03Z...BUT CONFIDENCE IS TOO LOW TO MENTION VCTS
AT THIS TIME. BRIEF IFR CONDITIONS WILL BE POSSIBLE IF TSRA DIRECTLY
IMPACTS A TERMINAL.

JACKSON

.PREV DISCUSSION... /ISSUED 437 AM CDT THU AUG 23 2012/

DISCUSSION...

TEMPERATURE-WISE...
HIGHS WILL GENERALLY BE NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE
WEEKEND...PUSHING A LITTLE FURTHER ABOVE NORMAL BY NEXT WEEK. LOWS
WILL BE ABOVE NORMAL THROUGH THE PD.

SIMPSON

FIRE WEATHER...

NEITHER ELEVATED NOR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
THROUGH THE NEXT SEVERAL DAYS...THOUGH BREEZY SOUTHERLY WINDS WILL BE
NOTED THROUGH SATURDAY.

SIMPSON

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

JJ/BJS

AREA FORECAST DISCUSSION

NWS DENVER CO

340 PM MDT THU AUG 23 2012

.SHORT TERM...A RATHER DISORGANIZED UPPER LEVEL TROUGH OVER
SOUTHERN UT AND NORTHERN AZ THIS AFTERNOON WILL SLOWLY MOVE EAST
ACROSS SOUTHERN COLORADO TONIGHT AND FRIDAY. THE AIRMASS WILL
REMAIN VERY MOIST BUT SO FAR THE SHOWERS AND TSTMS HAVE BEEN SLOW
TO DEVELOP THIS AFTERNOON. THE LATEST HRRR HOWEVER CONTINUES TO
DEVELOP PRECIPITATION OVER THE CWFA TONIGHT...WITH THE BEST
POTENTIAL TO THE WEST AND SOUTH OF DENVER. PRECIPITABLE WATER
VALUES WILL BE OVER ONE INCH WITH SLOW STORM MOTIONS SO A FEW
STORMS COULD PRODUCE BRIEF HEAVY RAINFALL...BUT EXTENSIVE CLOUD
COVER TODAY HAS LIMITED THEIR DEVELOPMENT SO FAR. WL KEEP THE POPS I
INHERITED FOR THE MOST PART...ONLY CHANGE WAS TO INCREASE THE POPS
TO CHC NEAR THE SRN FRONT RANGE FOOTHILLS AND PALMER DIVIDE. IN A
NUTSHELL...ALTHOUGH THE POTENTIAL FOR HEAVY RAIN EXISTS FOR THE
BURN AREAS...THE THREAT STILL TO BE MODERATE UNTIL MAYBE O2Z THEN LOW.
ON FRIDAY...VERY SIMILAR TO TODAY WITH A BIT MORE WARMING.
FORECAST SOUNDINGS FRIDAY AFTERNOON RANGE 200-300 J/KG AT KDEN TO
700-1100 J/KG AND KLIC AND KAKO RESPECTIVELY. THERE WILL BE SOME
WEAK QG ASCENT ASSOCIATED WITH THE TROUGH WHICH MAY HELP ENHANCE
THE PCPN BUT EXTENSIVE CLOUD COVER MAY AGAIN LIMIT THE STRENGTH/COVERAGE
OF THE TSTMS. BEST POPS WILL BE OVER THE SRN HALF OF THE CWFA
WITH DRYING DEVELOPING OVER THE NRN HALF OF THE CWFA ONCE THE
SYSTEM MAKES ITS WAY INTO SERN CO LATE IN THE DAY.

.LONG TERM...TROUGH TO BE CENTERED ACROSS EASTERN COLORADO FRIDAY
EVENING. SHOULD CONTINUE TO SEE DRIER AND MORE SUBSIDENT AIR
MOVING IN FROM THE NORTH. STILL SOME CHANCE FOR THUNDERSTORMS...MAINLY
ACROSS THE SOUTHERN SECTIONS OF THE CFWA IN THE AREA OF BEST MID
LEVEL QG ASCENT. PRECIPITABLE WATER VALUES ON THE DECREASE...BUT
STILL CLOSE TO AN INCH ALONG PALMER DIVIDE. MAY STILL SEE BRIEF
MODERATE TO HEAVY RAIN WITH THE STORMS THERE...WITH LIGHTER
AMOUNTS ELSEWHERE. COULD ALSO SEE SOME GUSTY OUTFLOW WINDS. TROUGH
TO SLOWLY MOVE INTO WESTERN KANSAS OVERNIGHT WITH MOST IF NOT ALL
OF THE ASCENT EAST OF THE AREA. FOR THIS REASON...WILL DROP MOST
OF THE POPS AND WEATHER AFTER MIDNIGHT KEEPING A SLIGHT CHANCE
OVER THE HIGHER MOUNTAINS. ON SATURDAY...TROUGH TO BE CENTERED
OVER CENTRAL AND WESTERN KANSAS AS UPPER RIDGE BUILDS ACROSS GREAT
BASIN. MODELS CONTINUE TO SHOW COLD FRONT MOVING THROUGH THE
PLAINS DURING THE EARLY MORNING HOURS. WINDS COULD GUST TO AROUND
20 KTS FOR A COUPLE HOURS FOLLOWING FRONT. COOLER AIR EXPECTED
FOLLOWING FRONT WITH HIGHS ONLY IN THE LOWER 80S ACROSS PLAINS.
THE COOLER AIR WILL ALSO HELP TO STABILIZE THE ATMOSPHERE.
MOUNTAINS NOT EXPECTED TO BE AFFECTED BY THE FRONT SOME
TEMPERATURES THERE TO BE SIMILAR TO FRIDAY`S READINGS. AIRMASS TO
BE SLIGHTLY UNSTABLE OVER THE HIGH COUNTRY BY THE AFTERNOON AND
WITH LINGERING MOISTURE...COULD SEE SOME HIGH BASED STORMS DEVELOP
ACROSS THE HIGHER TERRAIN DURING THE AFTERNOON CONTINUING INTO THE
EVENING. FOR SUNDAY...HIGH PRESSURE TO CONTINUE TO BUILD ACROSS
GREAT BASIN AS WELL AS WESTERN COLORADO. AS A RESULT...AIRMASS TO BE
MAINLY DRY AND WARMER WITH HIGHS INTO THE MID AND UPPER 80S ACROSS
PLAINS. STILL SOME MOISTURE NOTED ON CROSS SECTIONS ACROSS
MOUNTAINS FOR A SLIGHT CHANCE OF AFTERNOON AND EVENING HIGH BASED
STORMS. BOTH NAM AND GFS HINT AT A WEAK DISTURBANCE MOVING ACROSS
CENTRAL PLAINS DURING THE AFTERNOON. THERE IS SOME WEAK QG ASCENT
AS WELL. BOTH MODELS ALSO PAINT SOME LIGHT QPF ACROSS AREA
INCLUDING PLAINS. BUT AIRMASS ALSO FAIRLY DRY AS NOTED BY LOWER
PRECIPITABLE WATER VALUES. FOR NOW WILL NOT INTRODUCE POPS FOR
PLAINS BUT WILL ADD A BIT MORE CLOUD.

FOR THE MONDAY THROUGH THURSDAY PERIOD...MODELS SHOW UPPER RIDGE
ACROSS COLORADO THROUGH THE PERIOD...THOUGH ECMWF SHOW RIDGE OVER
CENTRAL PLAINS BY LATE WEDNESDAY WITH UPPER TROUGH ACROSS GREAT
BASIN. ECMWF LOOKS TO THE THE OUTLIER AT THIS POINT AND WILL
DISCOUNT. SO SHOULD SEE A MAINLY DRY AND WARM AIRMASS OVER THE
AREA THROUGH THE PERIOD. SOME MOISTURE WILL BE PRESENT FOR A
SLIGHT CHANCE OF THUNDERSTORMS OVER THE HIGH COUNTRY EACH
AFTERNOON AND EVENING. GUIDANCE INDICATING HIGHS COULD BE 90
DEGREES OR BETTER DURING THIS PERIOD...WHICH WILL LIKELY BREAK THE
STRING OF DAYS OF 90 DEGREES OR GREATER FOR DENVER...THE RECORD
BEING 61 DAYS. CURRENTLY DENVER ONLY 2 DAYS FROM TYING THE
RECORD...AND STRING COULD BE BROKEN WEDNESDAY IF GUIDANCE IS
CORRECT.

.AVIATION...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. SHOWERS
AND TSTMS DEVELOPING WEST AND SOUTH OF DENVER SHOULD DRIFT INTO
THE DENVER AREA THROUGH O0-02Z. IF TSTMS DEVELOP AT KDEN THEN CIGS
COULD DEVELOP IN THE 5-6 KFT AGL RANGE. WITH SFC LOW TO THE SOUTH
WINDS MAY CONTINUE TO FLUCTUATE FM NWLY TO NELY THROUGH THIS
EVENING. DEVELOPING SHOWERS AND TSTMS WILL ONLY CONFUSE THE ISSUE
FURTHER. SHOULD SEE WINDS TRANSITION TO SWLY LATE THIS EVENING
BUT DRAINAGE WINDS WILL BE SLOW TO DEVELOP WITH SHOWERS AND CLOUD
COVER LINGERING OVERNIGHT.

.HYDROLOGY...THREAT OF THUNDERSTORMS WILL BE GREATEST PRIOR TO 02Z
WITH LINGERING LIGHT RAIN SHOWERS OVERNIGHT. A THUNDERSTORM THIS
AFTN OR EARLY THIS EVENING COULD PRODUCE A MODERATE TO HEAVY RAIN
SHOWER WITH A QUARTER OF ONE HALF INCH OF RAIN IN 30 MINUTES. IN
SPITE OF THE HIGH MOISTURE CONTENT EXTENSIVE CLOUD COVER HAS
LIMITED THE TSTMS DEVELOPMENT SO FAR THIS AFTN. THE THREAT OF HEAVY
RAIN WILL BE MODERATE IN THE BURN AREAS UNTIL 02Z THEN LOW
THEREAFTER.

.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...COOPER
LONG TERM....D-L
AVIATION...COOPER

AREA FORECAST DISCUSSION

NWS ALBANY NY

130 PM EDT THU AUG 23 2012

.SYNOPSIS...
HIGH PRESSURE WILL BE SITUATED JUST TO THE SOUTHWEST OF
THE REGION THIS AFTERNOON. THIS WILL ALLOW FOR A GOOD DEAL OF
SUNSHINE AND DRY WEATHER...ALONG WITH WARM TEMPERATURES. THIS HIGH
PRESSURE AREA WILL REMAIN OVER THE NORTHEAST INTO THE
WEEKEND...ALLOWING FOR MAINLY DRY WEATHER WITH CONTINUED WARM
TEMPERATURES.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 130 PM...HIGH CLOUDS HAVE MOVED OUT OF THE REGION. WE DO HAVE
SOME PRETTY GOOD CU BUILDUPS...MAINLY OVER THE HIGHER TERRAIN. MODEL
SOUNDINGS INDICATED ONLY MODEST INSTABILITY (MAYBE UP TO 500 J/KG)
ALONG WITH A WEAK MID LEVEL CAP DEVELOPING DURING THE AFTERNOON. THE
LATEST EXPERIMENTAL HRRR AND HIRESWRF INDICATE NOTHING MORE THAN
SOME POSSIBLE SPRINKLES OVER THE HIGHER TERRAIN (DZ VALUES LESS THAN
25). MOISTURE REMAINS SOMEWHAT LIMITED THROUGH THE COLUMN.

FOR THE AFTERNOON...THE ONLY CHANGE WAS TO ADD SOME CLOUDS ACROSS
THE HIGHER TERRAIN (AND CALL IT PARTLY SUNNY THERE).
OTHERWISE...LEFT THE HIGH TEMPERATURES ALONE AND ONLY MINOR
RE-TOOLING OF THE HOURLY GRIDS REQUIRED.

LOOK FOR HIGHS IN THE MID 80S ACROSS MOST VALLEY AREA...MID 70S TO
LOWER 80S ACROSS THE HIGHER TERRAIN. THE WIND WILL REMAIN VARIABLE
TO WEST GENERALLY UNDER 10 MPH.

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE HIGH PRESSURE AREA WILL REMAIN ANCHORED OVER THE REGION
THROUGH MUCH OF THE SHORT TERM PERIOD. SKIES WILL REMAIN FAIRLY
CLEAR TONIGHT...EXCEPT FOR SOME PATCHY FOG THAT MAY DEVELOP LATE
AT NIGHT IN SOME AREAS...ESP NEAR BODIES OF WATER. WITH THE
CONTINUED GOOD RADIATIONAL COOLING...IT WILL BE ANOTHER
COMFORTABLE NIGHT WITH LOWS RANGING FROM THE UPPER 40S TO THE
UPPER 50S.

CONTINUED SUNNY SKIES AND WARM TEMPERATURES ARE EXPECTED AGAIN FOR
FRIDAY. 850 HPA TEMPS MAY EVEN NUDGE A DEGREE OR TWO WARMER...SO
SOME UPPER 80S ARE POSSIBLE IN THE HUDSON VALLEY. DEWPOINTS WILL
START TO CREEP UP AS WELL...WITH SOME READINGS IN THE UPPER 50S TO
NEAR 60 F...SO IT WILL START TO FEEL A LITTLE MORE MUGGY THAN
RECENT DAYS...ALTHOUGH CERTAINLY NOT AS BAD AS IT COULD BE FOR
THIS TIME OF YEAR.

THE MOSTLY CLEAR SKIES WILL CONTINUE INTO FRIDAY NIGHT AS
WELL...WITH THE HIGH PRESSURE STILL OVER THE AREA. MIN TEMPS MAY
BE A LITTLE WARMER THAN RECENT NIGHTS...WITH MINS NEAR 60 FOR THE
CAPITAL REGION.

BY SATURDAY...THE HIGH WILL START TO SHIFT OFF THE COAST...AND A
MOIST SOUTHERLY FLOW WILL START TO KICK IN. SOME OF THE MODELS
HINT AT A VERY WEAK UPPER LEVEL DISTURBANCE OVER THE MID ATLANTIC
STATES. THIS NEARBY UPPER LOW...COMBINED WITH THE INCREASING
HUMIDITY...AND DAYTIME HEATING...MIGHT ALLOW FOR AN ISOLD TO
SCATTERED SHOWER OR THUNDERSTORM TO DEVELOP IN THE
AFTERNOON...MAINLY FOR THE HIGHER TERRAIN AREAS TO THE SOUTHWEST
OF THE CAPITAL REGION. DUE TO THE POSSIBLE PRECIP...AND PERHAPS A
FEW MORE CLOUDS AND THE MORE HUMID SOUTHERLY FLOW...MAX TEMPS ON
SATURDAY MAY BE A FEW DEGREES LESS THAN FRIDAY...WITH READINGS IN
THE MID 80S.

ANY SHOWER OR THUNDERSTORM THREAT SHOULD END WITH THE LOSS OF
HEATING FOR SATURDAY NIGHT...WITH A MOSTLY CLEAR TO PARTLY CLOUDY
SKY OVERNIGHT. MIN TEMPS WILL RANGE FROM THE MID 50S TO THE MID
60S...AND IT WILL REMAIN A LITTLE ON MUGGY SIDE.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
DRY WEATHER IS EXPECTED TO HOLD THROUGH SUNDAY. THE RIDGE OF HIGH
PRESSURE WILL FINALLY SLIDE EAST OF THE FA AND WEAKEN ON MONDAY AS A
COLD FRONT MOVES INTO THE CENTRAL AND EASTERN GREAT LAKES. THIS
FEATURE WILL RESULT IN A CHANCE OF SHOWERS AND A SLIGHT CHANCE OF
THUNDERSTORMS FROM MONDAY AFTERNOON INTO TUESDAY. A WAVE OF LOW
PRESSURE MAY DEVELOP AND MOVE NORTHEAST ALONG THE FRONT KEEPING
UNSETTLED WEATHER ACROSS THE FA INTO TUESDAY AFTERNOON. HIGH
PRESSURE IS THEN EXPECTED TO RETURN ON WEDNESDAY WITH DRIER
CONDITIONS.

ON SUNDAY...HIGH PRESSURE WILL REMAIN ANCHORED ACROSS THE NORTHEAST
STATES FOR ONE MORE DAY WITH SLIGHTLY ABOVE NORMAL TEMPS AS HIGHS
ARE EXPECTED TO BE IN THE UPPER 70S TO LOWER 80S WITH LOWS SUNDAY
NIGHT IN THE 50S TO LOWER 60S.

MONDAY AND TUESDAY...IT NOW APPEARS THAT UNSETTLED WEATHER WILL
RETURN BY MONDAY AFTERNOON AND LINGER INTO TUESDAY WITH COLD FRONT
MOVING FROM CENTRAL GREAT LAKES MONDAY MORNING INTO FA TUESDAY
MORNING AS A WAVE OF LOW PRESSURE TRACKS NORTHEAST ALONG THE FRONT
FROM THE OHIO VALLEY. SHOWALTER INDICES DROP TO AROUND ZERO FROM
MONDAY AFTERNOON INTO TUESDAY...SO SOME EMBEDDED THUNDERSTORMS
POSSIBLE AND WILL INCLUDE SLIGHT CHANCE OF THUNDERSTORMS ALONG WITH
CHANCE POPS AT THIS TIME. QPF AMOUNTS ARE HIGHLY UNCERTAIN AT THIS
TIME. HIGHS ARE EXPECTED TO BE IN THE UPPER 70S TO MID 80S ON MONDAY
AND 70S TO LOWER 80S ON TUESDAY WITH SOME UPPER 60S POSSIBLE ACROSS
THE WESTERN ADIRONDACKS. LOWS MONDAY NIGHT ARE EXPECTED TO BE IN THE
UPPER 50S TO MID 60S.

TUESDAY NIGHT AND WEDNESDAY...EXPECT A RETURN TO DRIER WEATHER AS
HIGH PRESSURE BUILDS EAST ACROSS THE GREAT LAKES INTO THE NORTHEAST
ON WEDNESDAY. EXPECT LOWS TUESDAY NIGHT IN THE UPPER 40S TO UPPER
50S WITH HIGHS ON WEDNESDAY IN THE UPPER 60S TO NEAR 80.

.AVIATION /17Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS ARE EXPECTED AT THE TAF SITES FOR MUCH OF THE TAF
PERIOD ENDING AT 18Z FRIDAY AS HIGH PRESSURE WILL REMAIN ACROSS OUR
REGION. THERE COULD BE SOME FOG EARLY TOMORROW MORNING AT KGFL...
KPSF AND KPOU TONIGHT LIKE IN THE PAST FEW EARLY MORNINGS. ONCE FOG
BURNS OFF EARLY IN THE MORNING...EXPECT SKC TO SCT CLOUD CONDITIONS
DURING THE REMAINDER OF TOMORROW MORNING.

THE WINDS WILL BE FROM THE WEST OR SOUTHWEST AT LESS THAN 8 KTS FROM
THROUGH THIS AFTERNOON. WINDS WILL BE CALM OR LIGHT AND VARIABLE
TONIGHT AND TOMORROW MORNING.

OUTLOOK...
FRI-SUN...MAINLY VFR CONDITIONS. CHC FOR LATE NT/EARLY AM
BR/FOG ESPECIALLY AT KGFL AND KPSF.
MON...VFR...SLIGHT CHC/CHC SHRA/TSRA.
TUE...VFR/MVFR CHC SHRA/TSRA.

.FIRE WEATHER...
HIGH PRESSURE WILL REMAIN CLOSE TO THE REGION THROUGH THE WEEKEND. IT
WILL REMAIN MAINLY DRY THROUGH THE WEEKEND...ALTHOUGH A STRAY
SHOWER OR THUNDERSTORM CANNOT BE RULED OUT ON SATURDAY.

RH VALUES WILL DROP TO 30-45 PERCENT THIS AFTERNOON...BUT WILL
RECOVER TO NEAR 100 PERCENT TONIGHT WITH DEW FORMATION. RH VALUES
WILL AGAIN DROP TO 35-50 PERCENT FOR SATURDAY AFTERNOON.

CALM WINDS THIS MORNING WILL PICK UP TO 5-10 MPH FROM THE W-SW FOR
THIS AFTERNOON. NEARLY CALM WINDS ARE EXPECTED AGAIN TONIGHT.
WINDS WILL REMAIN LIGHT AND VARIABLE FOR FRIDAY.

.HYDROLOGY...
NO HYDRO PROBLEMS ARE EXPECTED FOR THE NEXT FIVE DAYS.

NO PRECIPITATION IS EXPECTED TODAY AND TOMORROW...WITH JUST AN
ISOLATED TO SCATTERED LIGHT RAIN SHOWER OR THUNDERSTORM ON
SATURDAY...MAINLY OVER THE HIGH TERRAIN OF THE CATSKILLS. IT
SHOULD STAY DRY FOR SUNDAY AND MONDAY. ANY SHOWER OR THUNDERSTORM
ON SATURDAY WOULD BE RATHER LIGHT...AND SHOULD HAVE LITTLE TO NO
EFFECT ON STREAM FLOW ACROSS THE REGION. RIVERS AND STREAMS WILL
REMAIN CLOSE TO CURRENT LEVELS OR SLOWLY RECEDE INTO EARLY NEXT
WEEK.

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.

$$
SYNOPSIS...FRUGIS/NAS
NEAR TERM...HWJIV/NAS
SHORT TERM...FRUGIS
LONG TERM...11
AVIATION...NAS
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

253 PM CDT THU AUG 23 2012

.DISCUSSION...
917 AM CDT

MADE SOME MINOR EDITS TO THE SKY COVER/WEATHER GRIDS THROUGH THE
AFTERNOON...TO ACCOUNT FOR PERSISTENT PARTLY CLOUDY/PARTLY SUNNY
SKIES AND POSSIBLE SCATTERED SPRINKLES.

RODRIGUEZ

//PREV DISCUSSION...
303 AM CDT

MDB

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 20Z...

* WINDS GUSTING INTO MID TEENS THIS AFTERNOON AND AGAIN FRIDAY
AFTERNOON.
* PRECIP CHANCES OVERNIGHT. BMD

//DISCUSSION...UPDATED 18Z...

OVERALL PATTERN REMAINS LARGELY UNCHANGED AND IS EXPECTED TO PERSIST
OVER THE NEXT 24 HRS OR SO. CONTINUE TO EXPECT SSW TO SSE WINDS
AROUND 10 KT. WINDS MAY GUST INTO THE MID TEENS THIS
AFTERNOON...WITH BETTER CHANCES TOMORROW AFTERNOON AS THE GRADIENT
TIGHTENS SLIGHTLY. ONLY OTHER CONCERN IN THE FORECAST IS PRECIP
CHANCES OVERNIGHT. NAM/GFS GUIDANCE IN PARTICULAR INDICATE A WEAK
UPPER LEVEL DISTURBANCE TRAVELING JUST NORTH OF THE AREA WITH WEAK
ISENTROPIC ASCENT HELPING TO DEVELOP A FEW SHOWERS. SOUNDINGS
CONTINUE TO LOOK DRY AND MAY BE AN INHIBITING FACTOR...BUT GIVEN THE
SHOWER ACTIVITY THAT HAPPENED THIS MORNING...ATMOSPHERE SEEMS
CAPABLE OF SUPPORTING AT LEAST SOME SHOWERS REACHING THE SURFACE
WITH MVFR CIGS IN THE HEAVIER SHOWERS. FOR NOW...DO NOT HAVE ENOUGH
CONFIDENCE IN SHOWERS IMPACTING TERMINALS SO WILL NOT MENTION IN
TAF. BMD

//ORD AND MDW CONFIDENCE...UPDATED 20Z...

* MEDIUM CONFIDENCE IN WIND GUST SPEEDS THIS AFTERNOON...MEDIUM TO
HIGH CONFIDENCE FOR FRIDAY AFTERNOON.
* MEDIUM CONFIDENCE WIDELY SCATTERED SHOWERS DEVELOPING LATE
TONIGHT/EARLY FRIDAY. LOW CONFIDENCE IN SHOWERS IMPACTING
TERMINALS.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. BMD

//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...

FRIDAY NIGHT...VFR. WX NIL.

SATURDAY...VFR. WX NIL.

SUNDAY...CHANCE TSRA. OTHERWISE...VFR.

MONDAY...CHANCE TSRA EARLY. OTHERWISE...VFR.

TUESDAY...VFR. WX NIL.

WEDNESDAY...VFR. WX NIL.

KREIN

.MARINE...
229 PM CDT

A TROUGH OF LOW PRESSURE STRETCHING FROM SASKATCHEWAN TO THE
SOUTHERN HIGH PLAINS WILL REMAIN NEARLY STATIONARY THROUGH FRIDAY
NIGHT...WHILE A DEEP AREA OF LOW PRESSURE DEVELOPS WITHIN THE
NORTHERN PERIPHERY OF THIS TROUGH OVER SASKATCHEWAN. THIS LOW WILL
MOVE NORTHEAST ACROSS MANITOBA SATURDAY AND SATURDAY NIGHT...AND
OVER HUDSON BAY SUNDAY AND SUNDAY NIGHT. THIS WILL SET UP A
PROLONGED PERIOD OF SOUTH WINDS ACROSS LAKE MICHIGAN THROUGH THE
WEEKEND. WARM AIR SPREADING ACROSS THE LAKE ON THESE SOUTH WINDS
WILL TEND TO LIMIT THE DEPTH OF THE MIXED LAYER OVER THE WATER...
WITH MODEL FORECAST SOUNDINGS DEPICTING 15-20 KTS AND SOME GUSTS
INTO THE 20-25 KT RANGE PARTICULARLY OVER THE NORTHERN AND NORTH
CENTRAL PARTS OF THE LAKE. SOME GUIDANCE DEPICTS A WEAKER SURFACE
WAVE DEVELOPING ACROSS THE MIDWEST BY EARLY SUNDAY...ALONG THE COLD
FRONT TRAILING THE DEEPER CANADIAN LOW. SOUTH-SOUTHEAST WINDS MAY
BRIEFLY PICK UP NEAR 20 KTS ON THE SOUTHERN PORTION OF THE LAKE
AHEAD OF THIS WAVE EARLY SUNDAY. THE COLD FRONT WILL THEN TRANSLATE
EAST ACROSS LAKE MICHIGAN SUNDAY NIGHT...WITH THE GRADIENT WEAKENING
IN THE VICINITY OF THE FRONTAL TROUGH WITH WINDS SHIFTING TO THE
NORTH-NORTHWEST. WEAK HIGH PRESSURE WILL THEN SPREAD ACROSS THE
UPPER MIDWEST BEHIND THE FRONT SUNDAY NIGHT AND MONDAY...MOVING
ACROSS THE WESTERN AND NORTHERN LAKES MONDAY NIGHT AND TUESDAY.

RATZER

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

230 PM CDT THU AUG 23 2012

.DISCUSSION...
917 AM CDT

MADE SOME MINOR EDITS TO THE SKY COVER/WEATHER GRIDS THROUGH THE
AFTERNOON...TO ACCOUNT FOR PERSISTENT PARTLY CLOUDY/PARTLY SUNNY
SKIES AND POSSIBLE SCATTERED SPRINKLES.

RODRIGUEZ

//PREV DISCUSSION...
303 AM CDT

MDB

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* WINDS GUSTING INTO MID TEENS THIS AFTERNOON AND AGAIN FRIDAY
AFTERNOON.
* PRECIP CHANCES OVERNIGHT. BMD

//DISCUSSION...UPDATED 18Z...

//ORD AND MDW CONFIDENCE...UPDATED 18Z...

//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...

FRIDAY NIGHT...VFR. WX NIL.

SATURDAY...VFR. WX NIL.

SUNDAY...CHANCE TSRA. OTHERWISE...VFR.

MONDAY...CHANCE TSRA EARLY. OTHERWISE...VFR.

TUESDAY...VFR. WX NIL.

WEDNESDAY...VFR. WX NIL.

KREIN

.MARINE...
229 PM CDT

RATZER

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

AREA FORECAST DISCUSSION

NWS LINCOLN IL

1225 PM CDT THU AUG 23 2012

.DISCUSSION...
ISSUED 1027 AM CDT THU AUG 23 2012

BARNES

.AVIATION...
ISSUED 1223 PM CDT THU AUG 23 2012

VFR WILL PREVAIL AT ALL TERMINALS THROUGH THE VALID TAF PERIOD.
CURRENT VISIBLE SATELLITE SHOWING MOSTLY CLEAR SKIES...WITH ONLY A
FEW MID AND HIGH CLOUDS MAINLY IN THE NORTH. THIS SHOULD BE THE CASE
THROUGH MOST OF THE PERIOD. WINDS WILL BE GENERALLY SOUTHERLY AOB 10
KTS TODAY...AND THEN BACK A BIT MORE TO THE SOUTHEAST OVERNIGHT.

ECT/BARNES
&&

HJS

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

AREA FORECAST DISCUSSION

NWS CHICAGO/ROMEOVILLE IL

1125 AM CDT THU AUG 23 2012

.DISCUSSION...
917 AM CDT

MADE SOME MINOR EDITS TO THE SKY COVER/WEATHER GRIDS THROUGH THE
AFTERNOON...TO ACCOUNT FOR PERSISTENT PARTLY CLOUDY/PARTLY SUNNY
SKIES AND POSSIBLE SCATTERED SPRINKLES.

RODRIGUEZ

//PREV DISCUSSION...
303 AM CDT

MDB

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 16Z...

* INCREASING SOUTHERLY WINDS BECMG 10KT GUSTING TO 15KT THIS
AFTERNOON. BMD

//DISCUSSION...UPDATED 12Z...

KREIN

//ORD AND MDW CONFIDENCE...UPDATED 16Z...

* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS. BMD

//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...

FRIDAY NIGHT...VFR. WX NIL.

SATURDAY...VFR. WX NIL.

SUNDAY...CHANCE TSRA. OTHERWISE...VFR.

MONDAY...CHANCE TSRA EARLY. OTHERWISE...VFR.

TUESDAY...VFR. WX NIL.

WEDNESDAY...VFR. WX NIL.

KREIN

.MARINE...
250 AM CDT

KREIN

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&

AREA FORECAST DISCUSSION

NWS QUAD CITIES IA IL

1215 PM CDT THU AUG 23 2012

.AVIATION...
VFR WX WILL BE SEEN THROUGH 00Z/25. DENSITY ALTITUDES MAY
APPROACH 3KFT THROUGH 00Z/24. THE MODELS ARE SUGGESTING THE
POTENTIAL FOR LLWS AFT 06Z/24. HOWEVER...THE CORE OF THE STRONGER
WINDS GENERALLY REMAIN IN CENTRAL IOWA. THUS THE POTENTIAL FOR
LLWS APPEARS MARGINAL FOR KCID/KDBQ. LLWS IS NOT EXPECTED AT
KMLI/KBRL. ..08..

.PREV DISCUSSION... /ISSUED 1043 AM CDT THU AUG 23 2012/

UPDATE...
A VERY MINOR UPDATE TO THE FCST HAS BEEN DONE TO HAVE IT REFLECT
CURRENT TRENDS.

PREV DISCUSSION... /ISSUED 333 AM CDT THU AUG 23 2012/

DLF

MONDAY THROUGH WEDNESDAY GENERALLY LOOKS DRY WITH NEAR TO ABOVE
NORMAL TEMPERATURES AS AN UPPER LEVEL RIDGE BUILDS TO THE WEST WITH
SURFACE HIGH PRESSURE OVER THE REGION.

SHEETS

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&

AREA FORECAST DISCUSSION

NWS DODGE CITY KS

1212 PM CDT THU AUG 23 2012

...UPDATED THE FOR THE 18Z AVIATION DISCUSSION AND SHORT TERM UPDATE...

.UPDATE...
ISSUED AT 1210 PM CDT THU AUG 23 2012

AFTER REVIEWING THE CURRENT CONDITIONS AND SHORT TERM MODELS SUCH
AS THE HRRR AND RAPID REFRESH MODELS, LOWERED POPS UNTIL AFTER 23Z
TODAY AND MOVED THE PRECIP FROM WEST TO EAST, SLOWLY RISING POPS
TONIGHT. ALSO, I ADDED THE MENTION OF POSSIBLE SEVERE WITH
DOWNBURST WINDS AND HEAVY RAIN IN THE NORTHERN ZONES, AFTER 23Z
AND UNTIL 04Z. THIS LAST UPDATE WAS MAINLY INFLUENCED BY THE DAY
ONE SPC CONVECTIVE OUTLOOK.

.SYNOPSIS...
ISSUED AT 108 AM CDT THU AUG 23 2012

WV IMAGERY AND 00Z UPPER AIR ANALYSIS INDICATE A WEAK NORTHWEST
FLOW ALOFT ACROSS THE WESTERN HIGH PLAINS. MEANWHILE, A CLOSED OFF
UPPER LEVEL LOW IS TRACKING EASTWARD ACROSS SOUTHERN NEVADA. NEAR
THE SURFACE, A LEE SIDE TROUGH OF LOW PRESSURE IS SET UP ACROSS
EASTERN COLORADO. SURFACE DEWPOINTS ARE IN THE UPPER 50S(F) TO
THE LOWER 60S(F) ACROSS CENTRAL AND SOUTHWEST KANSAS.

.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 300 AM CDT THU AUG 23 2012

SHORT RANGE MODELS INDICATE THE CLOSED OFF UPPER LEVEL LOW PUSHING
SLOWLY EAST INTO THE FOUR CORNERS REGION TODAY. MEANWHILE, A
DOWNSTREAM UPPER LEVEL SHORTWAVE IS PROJECTED TO EJECT EAST OUT OF
THE ROCKIES THIS MORNING AND INTO THE WESTERN HIGH PLAINS OF WESTERN
NEBRASKA AND NORTHEASTERN COLORADO THIS AFTERNOON. THIS WILL SET THE
STAGE FOR POSSIBLE SHOWER AND THUNDERSTORM DEVELOPMENT INTO
PORTIONS OF WESTERN KANSAS LATER TODAY AS LOW LEVEL MOISTURE
CONTINUES TO ADVECT NORTHWARD OUT OF THE TEXAS AND OKLAHOMA
PANHANDLES. NAM AND GFS MODEL SOUNDINGS SUGGEST INCREASED
INSTABILITY LEVELS INTO THIS AFTERNOON WITH CAPE VALUES IN THE
ORDER OF 1500 TO 2000 J/KG ACROSS CENTRAL AND EASTERN PORTIONS OF
SOUTHWEST KANSAS WHILE LOW/MID LEVEL LAPSE RATES STEEPEN WITH
DAYTIME HEATING. ADDITIONAL SUPPORT COULD COME LATE THIS AFTERNOON
AND EVENING AS A LOW LEVEL JET DEVELOPS ACROSS THE SAME GENERAL
AREA AHEAD OF A STRENGTHENING SURFACE LOW IN SOUTHEASTERN
COLORADO. HOWEVER, ALL MODELS INDICATE THE FLOW ALOFT REMAINING
FAIRLY WEAK ALONG WITH MODEST VERTICAL SHEAR AT BEST. THIS MAY
LIMIT THE COVERAGE AND STRENGTH OF ANY DEVELOPING SHOWERS AND
THUNDERSTORMS AS THE UPPER LEVEL SHORTWAVE KICKS OUT. STILL, THE
BEST CHANCE FOR PRECIP LOOKS TO BE ACROSS CENTRAL AND EASTERN
PORTIONS OF WESTERN KANSAS WHERE THE BEST LOW LEVEL LIFT WILL
LIKELY BE IN RESPECT TO THE SURFACE LOW...AND IN CONJUNCTION WITH
THE EXPECTED DEVELOPMENT OF A LOW LEVEL JET. ALTHOUGH WIDESPREAD
SEVERE WEATHER IS NOT EXPECTED, ENOUGH INSTABILITY EXISTS THAT A
FEW STORMS COULD BECOME FAIRLY STRONG CAPABLE OF PRODUCING GUSTY
WINDS IN EXCESS OF 40 TO 50 MPH AND POSSIBLE NICKEL TO QUARTER SIZE
HAIL. AREAS OF LOCALLY HEAVY RAIN MAY OCCUR AS WELL WITH NAM/GFS
MODEL SOUNDINGS SHOWING PW VALUES IN EXCESS OF 1.5 INCHES. WILL
INCREASE CHANCE CATEGORY POPS UP TO LOW END LIKELY CATEGORY POPS
GENERALLY ACROSS CENTRAL KANSAS FOR TONIGHT PER REASONS DISCUSSED
EARLIER.

TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL TODAY AS LEE SIDE
TROUGHING CONTINUES TO HELP INFLUENCE A LOW LEVEL SOUTHERLY FLOW
ACROSS WESTERN KANSAS. THIS WILL ENHANCE WARM AIR ADVECTION INTO
THE AREA WITH H85 TEMPERATURES CLIMBING SLIGHTLY OVER YESTERDAY
WITH VALUES IN THE LOWER TO MID 20S(C) ACROSS CENTRAL KANSAS TO
THE UPPER 20S(C) IN FAR SOUTHWEST KANSAS. ALTHOUGH INCREASED
CLOUDS MAY HINDER CLIMBING TEMPERATURES A LITTLE, HIGHS ARE STILL
EXPECTED TO RANGE ANYWHERE FROM THE UPPER 80S(F) TO THE LOWER TO
MID 90S(F) THIS AFTERNOON. EXPECT LOWS DOWN INTO THE 60S(F) FOR
THE MOST PART ONCE AGAIN TONIGHT, PARTICULARLY WITH AREAS OF
PRECIP ABOUT.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 205 AM CDT THU AUG 23 2012

A WET PERIOD...WHICH WILL COMMENCE LATER ON TODAY...WILL CONTINUE
THROUGH LATE SATURDAY NIGHT/EARLY SUNDAY AS A VERY SLOW MOVING UPPER
LEVEL DISTURBANCE MOVES FROM THE DESERT SOUTHWEST THROUGH THE
SOUTHERN/CENTRAL ROCKIES AND ACROSS THE CENTRAL PLAINS. WHILE IT IS
VERY DIFFICULT TO FORECAST THE FINER SCALE ATMOSPHERIC MOTIONS WHICH
WILL DICTATE DAILY THUNDERSTORM COMPLEXES...THE INGREDIENTS WILL BE
IN PLACE FOR SUSTAINED RAIN AND THUNDERSTORMS ACROSS A LARGE PORTION
OF THE FORECAST AREA THROUGH SATURDAY NIGHT. THESE INGREDIENTS
INCLUDE AN ABNORMALLY HIGH DEGREE OF ATMOSPHERIC MOISTURE (PWAT
VALUES AVERAGING 1.65 WAKEENEY-DODGE CITY LINE TO 1.85 INCHES AROUND
BARBER COUNTY, OR AROUND +2 STANDARD DEVIATION OF CLIMATOLOGICAL
NORMAL FOR DODGE CITY IN AUGUST) AND A SUSTAINED AXIS OF LOW LEVEL
CONVERGENCE AND DEFORMATION TIED TO THE UPPER LEVEL DISTURBANCE
ACROSS WESTERN KANSAS. OF COURSE...THESE LOW LEVEL BOUNDARIES WILL
BE AUGMENTED BY CONVECTIVE OUTFLOWS...BUT THERE IS NOT EXPECTED TO
BE A STRONG COLD FRONT THROUGH THIS ENTIRE PERIOD THAT WOULD REMOVE
THE MOISTURE FROM THE AREA...UNTIL LATE SATURDAY/SATURDAY
NIGHT...AND MORE LIKELY SUNDAY ACROSS SOUTH-CENTRAL KANSAS.

AS FAR AS THE GRIDS GO FOR 12-HR PERIOD POPS...THE PLAN IS TO KEEP
THE GOING FORECAST AS-IS FOR NOW...WHICH DOES INCLUDE LIKELY POPS
ACROSS MUCH OF SOUTHWEST-CENTRAL-SOUTH CENTRAL KS FRIDAY NIGHT INTO
SATURDAY...WITH 40-50 PERCENT CHANCE POPS SATURDAY NIGHT SOUTHEAST
OF A HAYS TO MEADE LINE. WHEN ALL IS SAID AND DONE BY THE END OF THE
WEEKEND...EVENT TOTAL PRECIPITATION IS EXPECTED TO BE ONE TO TWO
INCHES (PERHAPS LOCALLY HIGHER) OVER A PORTION OF CENTRAL, SOUTH
CENTRAL, AND SOUTHWEST KANSAS...ESPECIALLY SOUTHEAST OF AN ASHLAND
TO LARNED LINE. DAILY HIGH TEMPERATURES FRIDAY THROUGH SUNDAY ARE
EXPECTED TO BE IN THE MID TO UPPER 80S...BUT WILL ALSO BE SUBJECT TO
BUST POTENTIAL IN SOME AREAS FROM CONVECTIVE OUTFLOWS. UPPER LEVEL
RIDGING WILL BEGIN TO INFLUENCE WESTERN KANSAS SUNDAY WITH A DRYING
OUT PERIOD BEGINNING THEN. HIGHS SUNDAY THROUGH MID-NEXT WEEK WILL
GENERALLY BE IN THE UPPER 80S TO LOWER 90S UNDER THE INFLUENCE OF
UPPER LEVEL HIGH PRESSURE.

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1200 PM CDT THU AUG 23 2012

HIGH THIN CLOUDS AND BREEZY SOUTH WINDS WILL GIVE VFR CONDITION
THIS AFTERNOON AND INTO THE EVENING. A MESOCYLONE SYSTEM OF RAIN
WILL FORM IN NORTH CENTRAL KANSAS THIS EVENING AND COUPLE WITH A
SURFACE DRY LINE TO PRODUCE STORMS MOVING WEST TO EAST ACROSS THE
TAF SITE THIS EVENING. A FEW OF THE STORMS, ESPECIALLY IN THE KHYS
SITE, MAY PRODUCE HEAVY DOWNPOURS AND WIND GUSTS TO 50 KTS.
EXACTLY WHERE THE SEVERE STORMS WILL BE IS HARD TO PINPOINT, SO
ONLY PROB30 GROUPS WERE USED AT THIS TIME. AFTER ABOUT 09 TO 10Z,
THE CONVECTION SHOULD SLOW DOWN AND MOVE EAST.

.PRELIMINARY POINT TEMPS/POPS...
DDC 90 65 82 67 / 30 50 50 60
GCK 90 65 83 68 / 30 40 30 50
EHA 90 65 88 67 / 30 30 30 40
LBL 92 65 87 68 / 30 40 40 50
HYS 90 65 86 68 / 20 50 50 60
P28 90 67 83 68 / 20 50 50 60

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SYNOPSIS...JJOHNSON
SHORT TERM...JJOHNSON
LONG TERM...UMSCHEID
AVIATION...BURKE

AREA FORECAST DISCUSSION

NWS MARQUETTE MI

144 PM EDT THU AUG 23 2012

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 516 AM EDT THU AUG 23 2012

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 516 AM EDT THU AUG 23 2012

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 143 PM EDT THU AUG 23 2012

VFR CONDITIONS ARE EXPECTED AT ALL SITES THROUGHOUT THE PERIOD.
POCKETS OF SHOWERS ARE ONGOING NEAR ALL SITES...WITH SOME RECENT
LIGHTNING STRIKES WITH THE CLUSTER NEAR SAW. MOST OF THIS ACTIVITY
SHOULD PASS ALL SITES DURING THE AFTERNOON. A RESURGENCE OF -SHRA
AND SOME THUNDER MAY DEVELOP LATE THIS EVENING...WITH A NORTHWARD
MOVING BAND AFFECTING CMX AND SAW...AND THEN AN EASTWARD MOVING BAND
AFFECTING IWD AND CMX. A LOW-LEVEL JET WILL CREATE WEAK LLWS AT ALL
SITES. THOUGH...WOULD NOT BE SURPRISED IF THE LLWS IS A TOUCH HIGHER
THAN WHAT IS FORECAST.
&&

.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 516 AM EDT THU AUG 23 2012

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

UPDATE...JLA
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...TK
MARINE...ROLFSON

AREA FORECAST DISCUSSION...UPDATED

NWS DULUTH MN

1235 PM CDT THU AUG 23 2012

.AVIATION...08/23/18Z ISSUANCE...
VFR...WITH PATCHES OF IFR IN FOG LATE TONIGHT. A MID DECK WITH
SCATTERED HIGH BASE THUNDERSTORMS WILL CONTINUE FROM THE IRON
RANGE EAST AND ACROSS NORTHWEST WISCONSIN. IN THE MOIST AND
UNSTABLE AIR MASS...IT IS POSSIBLE FOR ISOLATED THUNDERSTORMS TO
DEVELOP TONIGHT. A POST-FRONTAL OFFSHORE FLOW WILL RESULTE IN VFR
WITH SCATTERED CLOUDS FRIDAY.

.PREV DISCUSSION... /ISSUED 1023 AM CDT THU AUG 23 2012/

UPDATE...GIVEN UNCERTAINTY IN FORCING MECHANISMS AND INCREASINGLY
UNSTABLE NATURE OF ATMOSPHERE...TOUGH TO CHANGE MUCH IN EXISTING
FCST. INITIAL SHORTWAVE TROF HAS MOVED INTO ERN CWA. THIS HAS
DRAGGED MAIN PWS PLUME FROM PINE COUNTY TO WRN BAYFIELD COUNTY.
INCREASED POPS OVER NWRN WISC THIS MORNING AS LATEST 88D SHOWS NEW
DEVELOPMENT OVER SRN PINE/BURNETT COUNTIES. RUC13 ANALYSIS SHOWS
FAIRLY WELL DEFINED WIND SHEAR AXIS FROM ARROWHEAD WEST TOWARDS NE
NODAK. NEW CELLS HAVE DEVELOPED OVER RANGE AND ARROWHEAD AND HAVE
RAISED POPS FOR THIS AREA TODAY. GENERAL IDEA IS THAT FIRST
SHORTWAVE WILL ADVECT EAST OF CWA BY AFTN. A DECREASE IN POPS OVER
SERN WISC ZONES WITH BETTER INSTABILITY TAXIS REALIGNING FROM BRD
LAKES VICINITY NORTHEAST INTO ARROWHEAD/RANGE. LOWERED MAX TEMPS A
FEW DEGREES OVER NWRN WISC DUE TO CLOUD COVER/PRECIP.

PREV DISCUSSION... /ISSUED 337 AM CDT THU AUG 23 2012/

MODELS IN DECENT AGREEMENT BUILDING HIGH PRESSURE INTO THE REGION
MONDAY WITH A DRY DAY EXPECTED.

HIGHS THROUGH THE PERIOD WILL GENERALLY RANGE FROM THE MID SEVENTIES
TO LOWER EIGHTIES.

.POINT TEMPS/POPS...
DLH 78 62 83 65 / 50 60 10 20
INL 81 59 83 62 / 50 40 10 50
BRD 82 63 86 68 / 50 50 10 30
HYR 81 64 86 64 / 60 60 30 20
ASX 80 64 84 64 / 50 60 30 20

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&

SHORT TERM...CANNON
LONG TERM....EOM
AVIATION...EOM

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

119 PM EDT THU AUG 23 2012

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 PM THURSDAY...I HAVE INCREASED POPS TO "LIKELY" FOR THE
REMAINDER OF THE AFTERNOON ALONG THE COAST FROM JUST SOUTH OF
WILMINGTON THROUGH THE GRAND STRAND...AND ALSO JUST NORTH OF
FLORENCE WHERE A CONCENTRATED BATCH OF SHOWERS RECENTLY HAS
DEVELOPED. OBVIOUSLY A FEW FOLKS UNDER THESE SLOW-MOVING SHOWERS ARE
GOING TO PICK UP SEVERAL INCHES OF RAIN...BUT BROADER SCALE AREAL
AVERAGES SHOULD BE AROUND HALF AN INCH. SYNOPTIC REASONING AS
EXPLAINED EARLIER IN UNCHANGED. PREVIOUS DISCUSSION FROM 10 AM
FOLLOWS...

THE FRONT IS EASILY DISCERNIBLE ON MORNING
VISIBLE SATELLITE IMAGERY AND EXTENDS FROM ABOUT 15 MILES EAST OF
GEORGETOWN TO 10 MILES NORTH OF THE FRYING PAN SHOALS TOWER TO ABOUT
70 MILES EAST OF WRIGHTSVILLE BEACH. THE LIGHT NE FLOW COVERING THE
EASTERN CAROLINAS IS NOT A SIGNIFICANTLY DIFFERENT AIRMASS THAN THAT
FOUND SOUTH OF THE FRONT...AND SHOULD DO NOTHING TO PREVENT SHOWERS
AND EMBEDDED THUNDERSTORMS FROM DEVELOPING LATER TODAY.

HIGHS SHOULD REACH THE LOWER 80S WITH PERHAPS A FEW MID 80S POSSIBLE
OUT WEST OF FLORENCE.

.AVIATION /18Z THURSDAY THROUGH MONDAY/...
AS OF 18Z...AREAS OF MVFR THIS WILL GRADUALLY IMPROVE TO VFR.
MVFR/IFR ANTICIPATED LATE OVERNIGHT INTO THE EARLY MORNING HOURS
DUE TO SHOWERS...STRATUS...AND FOG. OTHERWISE EXPECT VFR.

THOUGH PATCHES OF VFR ARE WITHIN THE AREA...MVFR RESTRICTIONS WILL
CONTINUE ACROSS PORTIONS OF THE AREA AS LOW STRATUS LINGERS AND
ISOLATED SHOWERS DEVELOP. INTO THE AFTERNOON...CLOUD COVER WILL
TEETER ON THE FENCE OF MVFR AND VFR...AS SHOWER DEVELOPMENT
INCREASES...WITH THE POSSIBILITY OF AN ISOLATED THUNDERSTORM AS
WELL. NORTHEAST WINDS WILL CONTINUE...WITH SUSTAINED WINDS AOB 10
KTS. INTO THE EVENING HOURS...WINDS WILL GRADUALLY BECOME
LIGHT...BUT THE OPPORTUNITY FOR ISOLATED SHOWERS WILL
CONTINUE...WITH A PERIOD OF RAIN-FREE SKIES LATE OVERNIGHT. INTO THE
MORNING HOURS...CONFIDENCE IS LOWERED ATTM DUE TO OPACITY OF ANY
STRATUS...THOUGH MID TO HIGH LEVEL CLOUDS WILL BE SCT/BKN. CANNOT
RULE OUT BRIEF HEAVY DOWNPOURS...THUS HAVE KEPT IN TEMPOS TO ACCOUNT
FOR THIS. AFTER MID MORNING...SHOWERS WILL TAPER OFF WITH SKY
COVERAGE GRADUALLY SCATTERING OUT...GIVING WAY TO VFR.

EXTENDED OUTLOOK...ISOLATED SHRA/TS SATURDAY AND MONDAY. SCT
SHRA/TS SUNDAY.

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM THURSDAY...NO SIGNIFICANT CHANGES FROM THE PREVIOUS
FORECAST. NE WINDS ARE RUNNING JUST A FEW KNOTS STRONGER THAN
EARLIER THOUGHT NEAR AND NORTH OF CAPE FEAR. PREVIOUS DISCUSSION
FROM 10 AM FOLLOWS...

THE FRONT HAS SLID SOUTH THROUGH VIRTUALLY ALL OF OUR FORECAST AREA
THIS MORNING...EXTENDING FROM APPROXIMATELY 15 MILES EAST OF
GEORGETOWN TO 10 MILES NORTH OF THE FRYING PAN SHOALS TOWER TO ABOUT
70 MILES EAST OF WRIGHTSVILLE BEACH. NORTHEAST WINDS 10-15 KT ON THE
NORTH SIDE OF THE BOUNDARY CONTRAST WITH LIGHT AND VARIABLE WINDS TO
THE SOUTH. EARLIER SHOWERS HAVE LARGELY DISSIPATED WITHIN 20 MILES
OF SHORE EXCEPT IN THE VICINITY OF THE FRONT NEAR FRYING PAN SHOALS.

SEAS RANGE FROM 2 FT TO AROUND 3 FT OUT AT THE FRYING PAN SHOALS
BUOY. LITTLE CHANGE IS EXPECTED THROUGH TODAY AND TONIGHT.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

$$
SYNOPSIS...SHK
NEAR TERM...RJD
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...SGL

AREA FORECAST DISCUSSION

NWS WILMINGTON NC

1241 PM EDT THU AUG 23 2012

HIGHS SHOULD REACH THE LOWER 80S WITH PERHAPS A FEW MID 80S POSSIBLE
OUT WEST OF FLORENCE.

EXTENDED OUTLOOK...ISOLATED SHRA/TS FRIDAY...SATURDAY AND MONDAY.
SCT SHRA/TS SUNDAY.

SEAS RANGE FROM 2 FT TO AROUND 3 FT OUT AT THE FRYING PAN SHOALS
BUOY. LITTLE CHANGE IS EXPECTED THROUGH TODAY AND TONIGHT.

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...MRR

AREA FORECAST DISCUSSION

NWS CHARLESTON WV

145 PM EDT THU AUG 23 2012

.NEAR TERM /THROUGH TONIGHT/...
DIURNAL CU HAS DEVELOPED OVER THE HIGHER ELEVATIONS AND OVER PARTS
OF THE LOWLANDS. EXPECT FEW SHOWERS OR STORMS TO FORM ALONG THE
RIDGE TOPS OF CENTRAL AND NORTHERN MOUNTAINS WITH LITTLE MOTION IF
ANY. ANY CONVECTION SHOULD START TO DIE OFF AROUND SUNSET.

PREVIOUS DISCUSSION BELOW...
LATEST RAP SHOWS UPPER TROUGH AXIS HAS FINALLY PASSED TO THE
EAST...WITH ONLY A FEW SPRINKLES STILL REMAINING OVER SOUTHERN
POCAHONTAS COUNTY. HIGH PRESSURE WILL CONTINUE AT THE
SURFACE...WITH A MAINLY WARM AND SUNNY DAY AHEAD. MODELS SHOWING
JUST ENOUGH MOISTURE THIS AFTERNOON...AND SOME WEAK BOUNDARY LAYER
CONVERGENCE/UPSLOPE FLOW IN THE WV MOUNTAINS...SO ADDED SOME
SCATTERED POPS...AND EXPANDED THE ISOLATED POPS A LITTLE IN OUR
EXTREME EASTERN ZONES. AS THE SLOW WARMING TREND
CONTINUES...EXPECT TODAY TO BE A DEGREE OR TWO WARMER THAN
YESTERDAY. PREVIOUS FORECAST FOR TODAYS HIGHS LOOKED GOOD AND MADE
NO SIGNIFICANT CHANGES THERE. ONLY SMALL ADJUSTMENTS MADE TO
TONIGHT LOWS AS WELL BY BLENDING IN THE MET WHICH HAS BEEN
OUTPERFORMING THE MAV FOR LOWS RECENTLY. THIS RESULTED IN A BIT
WARMER FORECAST IN THE NORTHERN MOUNTAIN ZONES.

BUT THE MAIN THEME CONTINUES TO THE THE WARM AFTERNOONS. DID
INCREASE MAXIMUM TEMPERATURES A FEW DEGREES IN SOME OF THE WESTERN
RIVER VALLEYS FOR FRIDAY AND SATURDAY...WITH THE DRY GROUND.

ANY WEAK UPSLOPE FLOW AT 925/850 MB SEEMS TO BE GONE BY SUNDAY. SO
MOST POPS AOB 14 PERCENT FOR SUNDAY.

ROLLED WITH HPC TEMPERATURES THROUGH THE PERIOD.

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
DIURNAL HEATING WILL CONTINUE TO PRODUCE SCATTERED LOW LEVEL CU
ABOUT 4K FEET ACROSS MOST AREAS EAST OF THE OH RIVER. ISOLATED TO
WIDELY SCATTERED SHOWERS WILL DEVELOP ALONG THE HIGHER MOUNTAINS
THIS AFTERNOON TO PRODUCE MVFR UNDER MODERATE RAIN. THESE STORMS
WILL BE SLOW MOVERS...BUT ARE NOT EXPECTED TO BE LONG LIVED OR AS
STRONG TO PRODUCE WIDESPREAD OR SIGNIFICANT PERIODS OF IFR
CONDITIONS. THEREFORE...INCLUDED VCTS AT BKW FOR NOW.

SKIES WILL CLEAR TONIGHT WITH DRIER AIR FILTERING IN FROM THE
WEST. RADIATIONAL COOLING COULD PRODUCE...ONCE AGAIN DENSE VALLEY
FOG MAINLY AT EKN...CRW AND CKB AFTER 08Z THROUGH 12Z. MVFR FOG IS
EXPECTED TO IMPACT THE REST OF SITES PER DRIER AIR AND LACK OF
ANTECEDENT PCPN.

ALL SITES IMPROVE TO VFR AFTER 13Z FRIDAY MORNING.

AN UPPER LEVEL VORT MAX APPROACHES FROM THE EAST INTO THE
APPALACHIAN LATE FRIDAY. THIS FEATURE COULD ENHANCE HIGHER TERRAIN
CONVECTION FRIDAY AFTERNOON. THEREFORE...KEPT THE POSSIBILITY OF
HAVING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TO DRIFT
WEST...PERHAPS REACHING CRW AND CKB INTO THE EVENING HOURS.
ATTM...CHANCES ARE LOW...SO DID NOT MENTION THESE CONDITIONS IN
TAF.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...

FORECAST CONFIDENCE: HIGH.

ALTERNATE SCENARIOS: TIMING AND EXTENT OF FOG COULD VARY.

UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
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 H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H

AFTER 18Z FRIDAY...
NO WIDESPREAD IFR CONDITIONS EXPECTED.

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

$$
SYNOPSIS...KTB/MZ
NEAR TERM...ARJ/MZ
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...ARJ

AREA FORECAST DISCUSSION

NWS NORMAN OK

1254 PM CDT THU AUG 23 2012

.AVIATION...
MAINLY VFR CONDITIONS WILL PREVAIL NEXT 24 HRS WITH
EXCEPTION OF MVFR CEILINGS/VISIBILITIES NEAR CLOSE
TO WIDELY SCATTERED/SCATTERED STORMS.

AREA OF SHOWERS AND EMBEDDED STORMS ACROSS NORTHWEST/
WEST CENTRAL OKLAHOMA EARLIER...HAS BEEN ON THE
DECREASE WITH RESPECT TO COVERAGE AND INTENSITY.
OTHER ISOLATED STORMS OVER CENTRAL OKLAOMA EARLY
THIS AFTERNOON SHOULD GRADUALLY WEAKEN AND MOVE
EAST.

UNTIL MAIN SYSTEM MOVES ACROSS THE SOUTHERN PLAINS
THIS WEEKEND...WILL LIKELY SEE AREAS OF SHOWERS/STORMS
FORM...ESPECIALLY NEAR STRONGER LOW LEVEL FLOW AND
MOIST MID-LEVEL WAA. THROUGH 18Z FRIDAY...THIS SHOULD
FAVOR TAF SITES CSM/WWR/GAG AND PERHAPS PNC.

.PREV DISCUSSION... /ISSUED 905 AM CDT THU AUG 23 2012/

UPDATE...
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP AND MOVE ACROSS
WESTERN PORTIONS OF THE FA THIS MORNING. THE ACTIVITY IS EXPECTED
TO WEAKEN LATER THIS MORNING/EARLY AFTERNOON. HAVE ADJUSTED POPS
TO ACCOUNT FOR CURRENT ACTIVITY. SKIES WILL BE CLOUDY/MOSTLY
CLOUDY ACROSS MUCH OF THE AREA THIS MORNING. WILL SEND UPDATES
SHORTLY.

MAXWELL

PREV DISCUSSION... /ISSUED 645 AM CDT THU AUG 23 2012/

PREV DISCUSSION... /ISSUED 342 AM CDT THU AUG 23 2012/

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 69 86 72 84 / 40 50 60 60
HOBART OK 68 89 70 89 / 40 50 50 30
WICHITA FALLS TX 70 91 74 93 / 30 30 30 30
GAGE OK 68 90 69 85 / 50 50 60 50
PONCA CITY OK 69 85 71 79 / 50 50 60 70
DURANT OK 68 89 73 90 / 10 20 40 60

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

AREA FORECAST DISCUSSION...UPDATED

NWS ABERDEEN SD

1244 PM CDT THU AUG 23 2012

.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW FOR THE 18Z TAF ISSUANCE.

PRECIPITATION HAS PUSHED OFF TO THE EAST OF THE REGION...SO HAVE
REMOVED ALL POPS FROM THE FORECAST FOR TODAY. NO CHANGES MADE TO
WINDS OR TEMPERATURES AT THIS TIME.

.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

DRY CONDITIONS EXPECTED TO PREVAIL AT THE LOCAL TAF SITES THE NEXT
24 HRS AS A WEAK AREA OF HIGH PRESSURE NOSES INTO THE REGION FROM
THE NORTHWEST. LIGHT WINDS THRU THE REMAINDER OF TODAY WILL SWITCH
TO THE SOUTH AND SOUTHEAST BY THE END OF THE TAF PERIOD. CLEAR TO
PARTLY CLOUDY SKIES WITH GENERALLY MID OR HIGH CLOUDS ANTICIPATED.
EXPECT VFR CONDITIONS TO PERSIST THE NEXT 24 HRS.

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

$$
UPDATE...PARKIN
SHORT TERM...TMT
LONG TERM...CONNELLY
AVIATION...VIPOND

WEATHER.GOV/ABERDEEN

AREA FORECAST DISCUSSION

NWS FORT WORTH TX

556 PM CDT THU AUG 23 2012

.AVIATION...
A MCV CAN BE SEEN ON VISIBLE IMAGERY THIS AFTERNOON OVER THE
SOUTHERN TEXAS PANHANDLE. A SMALL THUNDERSTORM CLUSTER HAS
DEVELOPED AHEAD OF THE FEATURE BETWEEN PADUCAH AND ASPERMONT
TX...AND IS MOVING SLOWLY EAST. ACTIVITY MAY AFFECT A FEW OF THE
WESTERN COUNTIES BEFORE DISSIPATING LATER THIS EVENING...BUT AT
THIS TIME IT IS EXPECTED TO REMAIN WELL WEST AND NORTHWEST OF TAF
SITES.

AT THE SURFACE...SOUTHEAST WINDS SHOULD REMAIN UP AROUND 8-10 KT
THIS EVENING AND OVERNIGHT IN RESPONSE TO A DEEPENING SURFACE LOW
IN LEE OF THE ROCKIES. WINDS WILL INCREASE INTO THE 10-15KT RANGE
AROUND MIDDAY FRIDAY. CONVECTION IS EXPECTED TO REMAIN NORTHWEST
OF THE NORTH TEXAS TERMINALS THROUGH THE MAJORITY OF THIS
FORECAST CYCLE. STORMS MAY BEGIN TO ENCROACH ON THE METROPLEX
FRIDAY EVENING AFTER 00Z BUT AT THIS TIME CONFIDENCE IS TOO LOW TO
INCLUDE IN THE EXTENDED DFW TAF.

.PREV DISCUSSION... /ISSUED 302 PM CDT THU AUG 23 2012/
CONVECTION FROM CHILDRESS TO SNYDER REMAINS WELL ELEVATED...WITH
BASES AOA 10KFT AGL. AS THE ACTIVITY MOVES EAST...IT WILL ENTER
AN AREA OF DEEPER MID-LEVEL MOISTURE. AS THE STORMS INGEST THIS
AIR...THE DCAPE (IN A LAGRANGIAN SENSE) WILL DIMINISH
CONSIDERABLY...AND THE THREAT OF DOWNBURST WINDS WILL BE
NEGLIGIBLE...DESPITE THE HIGH BASES. WITH WEAK SHEAR AND MOIST
ADIABATIC LAPSE RATES ALOFT...THE CONVECTION IS UNLIKELY TO
INTENSIFY...BUT IT MAY HOLD TOGETHER LONG ENOUGH TO REACH FAR
WESTERN ZONES LATE THIS AFTERNOON OR EARLY EVENING BEFORE
DISSIPATING. THE CU FIELD JUST WEST OF THE CWA IS BASED AROUND
5KFT AND APPEARS TO BE CAPPED...BUT WITH ANY FORCING ABOVE
800MB...THE MINIMAL INHIBITION CURRENTLY IN PLACE SHOULD BE ERODED
SUFFICIENTLY TO ALLOW SOME CELLS TO BECOME SURFACE-BASED.
REGARDLESS...THE BOUNDARY-LAYER INSTABILITY IS UNIMPRESSIVE...AND
ENTRAINING THIS SURFACE AIR WOULD ONLY FURTHER DECREASE THE
DOWNBURST THREAT.

SEA BREEZE CONVECTION IS CURRENTLY CONFINED TO THE HOUSTON METRO
AREA. AS SUCH...CONFIDENCE IS DIMINISHING FURTHER IN THE POTENTIAL
FOR ANY PROPAGATING OUTFLOW BOUNDARIES REACHING THE CWA. AS WITH
PREVIOUS RUNS...THE 18Z RUC MAINTAINS SOME CONVECTIVE CELLS IN FAR
SOUTHEAST ZONES...WHERE THE PROFILE WILL BECOME INCREASINGLY
TROPICAL. WITH DEEPENING MOISTURE AND DIMINISHING SUBSIDENCE...
WILL CONTINUE TO CARRY SOME ISOLATED MENTION IN THE SOUTHEAST.

LAS VEGAS HAD TALLIED ONLY 1.53 INCHES OF PRECIP IN 11 MONTHS
BEFORE RECEIVING A DELUGE OF 1.65 INCHES ON WEDNESDAY. (THIS
EASILY BROKE THE DAILY RECORD OF 0.23 INCHES.) THE OFFENDING
SHORTWAVE CONTINUES TO DEEPEN OVER THE FOUR CORNERS...WITH
WIDESPREAD CONVECTION DOWNSTREAM ACROSS NEW MEXICO AND COLORADO.
AS THE SYSTEM REACHES THE TEXAS PANHANDLE...IT WILL BE IN PHASE
WITH THE CYCLONE NEAR THE CANADIAN BORDER. AS A RESULT...THE
FEATURE WILL LIKELY SHEAR AND BE DRAWN NORTHWARD. WITH THE ENERGY
FARTHER NORTH...THE PRECIPITATION CHANCES FOR NORTH TEXAS THIS
WEEKEND WOULD BE REDUCED. WILL MAINTAIN BEST CHANCES GENERALLY
ALONG THE RED RIVER VALLEY. DESPITE THE LIKELY EVOLUTION OF THE
CONVECTIVE EVENT...EXTENDED GUIDANCE IS STILL FAVORING A RESULTING
EROSION OF THE RIDGE ABOVE NORTH TEXAS.

THE SHORTWAVE (AND MUCH LARGER CYCLONE) WILL ALLOW MILDER AIR TO
INVADE THE CENTRAL PLAINS. BUT WITH NEAR NORMAL TEMPERATURES
EXPECTED WITH THE SURFACE ANTICYCLONE...IT WOULD SUGGEST A
TENDENCY FOR THE ASSOCIATED FRONTAL BOUNDARY TO FAIL TO PENETRATE
THE SOUTHERN PLAINS. BUT IF THE RIDGE DOES ERODE ENOUGH TO ALLOW
FOR NORTHERLY FLOW...THE BOUNDARY COULD CERTAINLY REACH NORTH
TEXAS. EVEN THE ECMWF...WHICH PROJECTS A MID-LEVEL RIDGE AXIS FROM
TEXAS INTO THE PRAIRIE PROVINCES EARLY NEXT WEEK...ALLOWS
NORTHERLY SURFACE FLOW TO SLIDE DOWN THE MISSISSIPPI VALLEY AND
BACKDOOR INTO NORTH TEXAS...INDUCED BY THE PROXIMITY OF ISAAC.
(THE LATEST ECMWF RUN TAKES ISAAC INTO DFW...BUT THE EURO WAS
ALREADY A FAR WESTERN OUTLIER...SO DO NOT HAVE MUCH CONFIDENCE IN
THIS LATEST SOLUTION.) EXPECT A WARMING TREND NEXT WEEK...DESPITE
ANY LIGHT NORTH WINDS. WHATEVER TRACK ISAAC TAKES...NORTH TEXAS
WOULD LIKELY BE IN A SUBSIDENT ZONE. A MORE EASTERLY TRACK WOULD
ALLOW THE PLAINS RIDGE TO INTENSIFY...WHILE A MORE WESTERLY TRACK
COULD PUT EAST TEXAS WITHIN THE RING OF STRONG DOWNWARD MOTION
AROUND THE PERIPHERY OF THE CIRRUS SHIELD. TEMPERATURES MAY REACH
THE UPPER 90S BY DAY 7 (THURSDAY AUGUST 30).

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 76 93 76 94 77 / 5 10 20 20 20
WACO, TX 74 94 75 94 76 / 5 10 10 10 10
PARIS, TX 70 91 71 91 73 / 5 20 30 50 20
DENTON, TX 73 93 75 94 76 / 5 10 20 20 20
MCKINNEY, TX 70 91 73 91 75 / 5 20 20 30 20
DALLAS, TX 75 91 76 94 77 / 5 10 20 20 20
TERRELL, TX 72 91 73 92 75 / 5 20 20 20 20
CORSICANA, TX 73 92 73 93 75 / 5 10 20 20 10
TEMPLE, TX 73 94 73 94 74 / 10 10 10 10 10
MINERAL WELLS, TX 72 94 72 94 73 / 10 10 20 20 20

.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.

30/

AREA FORECAST DISCUSSION

NWS FORT WORTH TX

302 PM CDT THU AUG 23 2012

.DISCUSSION...
CONVECTION FROM CHILDRESS TO SNYDER REMAINS WELL ELEVATED...WITH
BASES AOA 10KFT AGL. AS THE ACTIVITY MOVES EAST...IT WILL ENTER
AN AREA OF DEEPER MID-LEVEL MOISTURE. AS THE STORMS INGEST THIS
AIR...THE DCAPE (IN A LAGRANGIAN SENSE) WILL DIMINISH
CONSIDERABLY...AND THE THREAT OF DOWNBURST WINDS WILL BE
NEGLIGIBLE...DESPITE THE HIGH BASES. WITH WEAK SHEAR AND MOIST
ADIABATIC LAPSE RATES ALOFT...THE CONVECTION IS UNLIKELY TO
INTENSIFY...BUT IT MAY HOLD TOGETHER LONG ENOUGH TO REACH FAR
WESTERN ZONES LATE THIS AFTERNOON OR EARLY EVENING BEFORE
DISSIPATING. THE CU FIELD JUST WEST OF THE CWA IS BASED AROUND
5KFT AND APPEARS TO BE CAPPED...BUT WITH ANY FORCING ABOVE
800MB...THE MINIMAL INHIBITION CURRENTLY IN PLACE SHOULD BE ERODED
SUFFICIENTLY TO ALLOW SOME CELLS TO BECOME SURFACE-BASED.
REGARDLESS...THE BOUNDARY-LAYER INSTABILITY IS UNIMPRESSIVE...AND
ENTRAINING THIS SURFACE AIR WOULD ONLY FURTHER DECREASE THE
DOWNBURST THREAT.

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 91 76 93 76 94 / 5 5 10 20 20
WACO, TX 91 74 94 75 94 / 5 5 10 10 10
PARIS, TX 92 70 91 71 91 / 5 5 20 30 50
DENTON, TX 91 73 93 75 94 / 10 5 10 20 20
MCKINNEY, TX 92 70 91 73 91 / 5 5 20 20 30
DALLAS, TX 91 75 91 76 94 / 5 5 10 20 20
TERRELL, TX 92 72 91 73 92 / 5 5 20 20 20
CORSICANA, TX 92 73 92 73 93 / 5 5 10 20 20
TEMPLE, TX 91 73 94 73 94 / 10 10 10 10 10
MINERAL WELLS, TX 91 72 94 72 94 / 10 10 10 20 20

.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.

05/25

AREA FORECAST DISCUSSION...UPDATED

NWS AMARILLO TX

1252 PM CDT THU AUG 23 2012

.AVIATION...
12Z SOUNDING FROM KAMA REVEALS THAT EARLY MORNING ATMOSPHERE HAD
BECOME MORE UNSTABLE DURING PAST 24 HOURS...WITH STEEPER MID-LEVEL
LAPSE RATE AND GREATER AMOUNT OF LOW-LEVEL MOISTURE IN PLACE. WITH
ADDITIONAL INSOLATION TO OCCUR THIS AFTERNOON...EXPECT SCATTERED
THUNDERSTORMS TO DEVELOP AROUND 21Z...AS MODEST MID-LEVEL SUPPORT
ARRIVES IN THE FORM OF VORTICITY MAXIMUM BEING EJECTED FROM 700 MB
TROF. EXPECT THAT DEVELOPMENT WILL OCCUR WEST OF TERMINALS NEAR
SURFACE TROF RUNNING THROUGH WESTERN PARTS OF FORECAST AREA.

SCATTERED THUNDERSTORMS EXPECTED TO CONTINUE THROUGH THE EVENING AS
HEALTHY LOW-LEVEL JET DEVELOPS. HAVE NOT INCLUDED MENTION OF THUNDER
AT KAMA AT THIS TIME...BUT WILL MONITOR CLOSELY AT AMEND IF
CONVECTION BECOMES A MORE REALISTIC THREAT AND WHEN TIMING OF SUCH
CAN BE BE ASCERTAINED. APART FROM BRIEF VISIBILITY REDUCTIONS IN
SCATTERED THUNDERSTORMS...VFR FORECAST CONTINUES NEXT 24 HOURS.

COCKRELL

.PREV DISCUSSION... /ISSUED 637 AM CDT THU AUG 23 2012/

AVIATION...
FOR THE 12Z TAFS...VFR CONDITIONS ARE EXPECTED OUTSIDE OF TSRA.

JACKSON

PREV DISCUSSION... /ISSUED 437 AM CDT THU AUG 23 2012/

DISCUSSION...

TEMPERATURE-WISE...
HIGHS WILL GENERALLY BE NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE
WEEKEND...PUSHING A LITTLE FURTHER ABOVE NORMAL BY NEXT WEEK. LOWS
WILL BE ABOVE NORMAL THROUGH THE PD.

SIMPSON

FIRE WEATHER...

NEITHER ELEVATED NOR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
THROUGH THE NEXT SEVERAL DAYS...THOUGH BREEZY SOUTHERLY WINDS WILL BE
NOTED THROUGH SATURDAY.

SIMPSON

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

03/16

AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

1219 PM CDT THU AUG 23 2012

.DISCUSSION...
SEE AVIATION DISCUSSION BELOW...

.AVIATION...
ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THIS
AFTERNOON ACROSS MUCH OF THE AREA...WITH THE BEST CHANCE AT KABI
AND KSJT. COVERAGE IS EXPECTED TO REMAIN ISOLATED...SO FOR NOW I
HAVE LEFT ANY MENTION OF THUNDER OUT OF THE TAFS. SOUTH WINDS OF
10 TO 15 KNOTS THIS AFTERNOON...WILL BECOME LIGHT AND VARIABLE
AROUND 00Z. PATCHY STRATUS DEVELOPMENT IS POSSIBLE...MAINLY OVER
THE NORTHWEST HILL COUNTRY...AFTER 10Z. BRIEF MVFR CONDITIONS WILL
BE POSSIBLE AT KJCT...BUT OVERALL EXPECT VFR CONDITIONS TO PREVAIL
AT ALL SITES THROUGH THE NEXT 24 HOURS. SOUTH WINDS WILL INCREASE TO
12 TO 16 KNOTS BY MID MORNING FRIDAY.

.PREV DISCUSSION... /ISSUED 1141 AM CDT THU AUG 23 2012/

UPDATE...
TO EXTEND POPS FARTHER EAST...

DISCUSSION...
LIGHT SHOWERS ARE ONGOING ACROSS PARTS OF THE NORTHERN EDWARDS
PLATEAU AND WESTERN CONCHO VALLEY. I WENT AHEAD AND EXTENDED POPS
TO INCLUDE MUCH OF WEST CENTRAL TEXAS THIS AFTERNOON AS MODELS
CONTINUE TO INDICATE AT LEAST ISOLATED SHOWERS AND THUNDERSTORMS
DEVELOPING. LAST SEVERAL RUNS OF THE HRRR INDICATE DECENT SURFACE
CONVERGENCE DEVELOPING ACROSS THE NORTHERN CONCHO VALLEY AND BIG
COUNTRY THIS AFTERNOON...WITH SCATTERED CONVECTION DEVELOPING. IN
ADDITION...DAYTIME HEATING WILL RESULT IN A MORE UNSTABLE
ENVIRONMENT WITH A DECREASING CAP. I EXTENDED SLIGHT CHANCE POPS
TO INCLUDE ALL OF THE AREA EXCEPT FOR PARTS OF THE NORTHWEST HILL
COUNTRY. I ALSO TWEAKED MAX TEMPERATURES DOWN SLIGHTLY OVER THE
WESTERN COUNTIES WHERE MORE CLOUD COVER IS FORECAST.
OTHERWISE...NO OTHER CHANGES NEEDED AT THIS TIME.

PREV DISCUSSION... /ISSUED 739 AM CDT THU AUG 23 2012/

DISCUSSION...
SEE 12Z AVIATION DISCUSSION BELOW.

AVIATION...
SATELLITE SHOWING A FEW LOW CLOUDS TRYING TO DEVELOP THIS MORNING
OVER THE NORTHWEST HILL COUNTRY. BRADY AIRPORT BRIEFLY HAD MVFR
CEILINGS YESTERDAY MORNING...BUT COVERAGE RIGHT NOW ON SATELLITE
NOT LOOKING AS PROMISING FOR TODAY. ADDED SCATTERED LOW CLOUDS FOR
A FEW HOURS THIS MORNING FOR JCT AND BBD. ELSEWHERE...EXPECT VFR
CONDITIONS. COULD SEE A LITTLE MORE WIDESPREAD LOW CLOUD COVERAGE
FOR TOMORROW MORNING...BUT CONFIDENCE LOW ENOUGH AND IT IS AT THE
END OF THIS TAF PERIOD...SO LEFT IT OUT FOR NOW. EXPECT SOUTHEAST
WINDS GENERALLY LESS THAN 15 KT.

PREV DISCUSSION... /ISSUED 424 AM CDT THU AUG 23 2012/

SHORT TERM...
NORTHWEST FLOW ALOFT CONTINUES OVER WEST CENTRAL TEXAS WITH A SERIES
OF WEAK EMBEDDED SHORTWAVE TROUGHS CONTINUING TO MOVE SOUTHEASTWARD
ACROSS THE AREA. A FEW LIGHT SHOWERS/VIRGA CURRENTLY ONGOING THIS
MORNING OVER IRION AND CROCKETT COUNTIES...WITH A FEW MORE SHOWERS
FURTHER BACK OVER THE PERMIAN BASIN. HAVE INCLUDED SLIGHT CHANCE OF
PRECIPITATION FOR FAR SOUTHWESTERN PART OF THE CWA FOR THE
MORNING...BUT DO NOT EXPECT MUCH CHANCE OF MEASURABLE RAINFALL WITH
THESE SHOWERS. WILL CONTINUE WITH A SLIGHT CHANCE OF PRECIP FOR THE
EVENING AS WELL IN THE SAME AREAS AS EXPECT TO SEE A FEW DIURNALLY
DRIVEN SHOWERS FOR THE AFTERNOON/EVENING AS WELL. WILL CONTINUE TO
SEE INCREASED CLOUD COVER FROM MID LEVEL CLOUDS WHICH WILL KEEP
AFTERNOON HIGHS GENERALLY IN THE LOWER TO MID 90S.

LONG TERM...
UPPER LOW OVER 4 CORNERS REGION PASSES OVER COLORADO AND INTO THE
CENTRAL PLAINS FRIDAY AND SATURDAY. KEEPING A SLIGHT CHANCE OF
STORMS IN DURING THIS PERIOD...NOT ONLY FOR THE UPPER DISTURBANCE
BUT WITH LOW LEVEL CONVERGENCE AS A SURFACE TROUGH DEVELOPS TO THE
LEE OF THE ROCKY MTS. BEST LIFT AND RAIN CHANCES WILL BE IN
WESTERN SECTIONS OF THE CONCHO VALLEY AND IN THE BIG COUNTRY.

GFS STILL HINTS AT A WEAK COLD FRONT MONDAY INTO TUESDAY...THOUGH
THE EC MODEL HANGS IT FARTHER NORTH ALONG THE RED RIVER. WILL
LEAVE OUT POPS FOR EARLY NEXT WEEK HOWEVER...WITH WEAKLY
SUBSIDENT CONDITIONS ASSOCIATED WITH UPPER LEVEL RIDGING. MIDWEEK
NEXT WEEK...THERE IS SOME DEPENDENCE IN THE TRACK OF ISAAC IN THE
GULF. 00Z GFS HOWEVER BRINGS IN DRIER NE LOW LEVEL FLOW OVER
TEXAS AS ISSAC MOVES INTO THE NE GULF OF MEXICO. THIS WOULD REDUCE
ALREADY REMOTE RAIN CHANCES...AND WILL KEEP WEDNESDAY DRY ALSO.

.PRELIMINARY POINT TEMPS/POPS...
ABILENE 72 93 72 93 74 / 10 20 20 20 10
SAN ANGELO 72 95 71 97 73 / 10 20 20 20 10
JUNCTION 69 94 72 97 74 / 10 10 20 10 10

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

DANIELS

AREA FORECAST DISCUSSION

NWS SAN ANGELO TX

1141 AM CDT THU AUG 23 2012

.UPDATE...
TO EXTEND POPS FARTHER EAST...

.DISCUSSION...
LIGHT SHOWERS ARE ONGOING ACROSS PARTS OF THE NORTHERN EDWARDS
PLATEAU AND WESTERN CONCHO VALLEY. I WENT AHEAD AND EXTENDED POPS
TO INCLUDE MUCH OF WEST CENTRAL TEXAS THIS AFTERNOON AS MODELS
CONTINUE TO INDICATE AT LEAST ISOLATED SHOWERS AND THUNDERSTORMS
DEVELOPING. LAST SEVERAL RUNS OF THE HRRR INDICATE DECENT SURFACE
CONVERGENCE DEVELOPING ACROSS THE NORTHERN CONCHO VALLEY AND BIG
COUNTRY THIS AFTERNOON...WITH SCATTERED CONVECTION DEVELOPING. IN
ADDITION...DAYTIME HEATING WILL RESULT IN A MORE UNSTABLE
ENVIRONMENT WITH A DECREASING CAP. I EXTENDED SLIGHT CHANCE POPS
TO INCLUDE ALL OF THE AREA EXCEPT FOR PARTS OF THE NORTHWEST HILL
COUNTRY. I ALSO TWEAKED MAX TEMPERATURES DOWN SLIGHTLY OVER THE
WESTERN COUNTIES WHERE MORE CLOUD COVER IS FORECAST.
OTHERWISE...NO OTHER CHANGES NEEDED AT THIS TIME.

.PREV DISCUSSION... /ISSUED 739 AM CDT THU AUG 23 2012/

DISCUSSION...
SEE 12Z AVIATION DISCUSSION BELOW.

PREV DISCUSSION... /ISSUED 424 AM CDT THU AUG 23 2012/

.PRELIMINARY POINT TEMPS/POPS...
ABILENE 92 72 93 72 93 / 20 10 20 20 20
SAN ANGELO 95 72 95 71 97 / 20 10 20 20 20
JUNCTION 95 69 94 72 97 / 20 10 10 20 10

.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

DANIELS