Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/22/14
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1118 AM MDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 1115 AM MDT FRI JUN 20 2014
FINE TUNED POP GRIDS OVER FAR SE PLAINS FOR THIS AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM MDT FRI JUN 20 2014
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING WEAK
WESTERLY FLOW ALOFT ACROSS THE REGION AS A MINOR DISTURBANCE (BEST
SEEN IN PV FIELDS) EMBEDDED WITHIN THE FLOW IS TRANSLATING ACROSS
THE STATE AT THIS TIME. THIS DISTURBANCE...ALONG WITH A LOW LEVEL JET
AND AMPLE LOW LEVEL MOISTURE...IS HELPING TO PRODUCE A FEW SHOWERS
AND THUNDERSTORMS ACROSS BENT...PROWERS AND KIOWA COUNTIES AT THIS
TIME. LATEST HI RES HRRR AND RUC MODELS...WHICH PICKED UP ON THIS
DEVELOPMENT LAST EVENING...MOVE THE DISTURBANCE AND STORMS EAST INTO
WESTERN KANSAS THROUGH 12Z FRI.
TODAY AND TONIGHT...MODELS KEEP WEAK WESTERLY FLOW ALOFT ACROSS THE
REGION THROUGH TONIGHT...AND WITH NO EVIDENT DISTURBANCE PROGGED
WITHIN THE FLOW...ANY STORMS TODAY LOOK TO BE INITIATED BY SOLAR
HEATING. WITH THAT SAID...LATEST MODELS REMAIN CONSISTENT WITH
DEVELOPING STORMS ACROSS THE FAR SE PLAINS...GENERALLY EAST OF A KIM
TO HASWELL LINE...WHERE CONVECTIVE TEMPS ARE IN THE LOW 90S AND DEW
PTS ARE PROGGED IN THE 40S TO LOWER 50S THIS AFTERNOON. THERE IS NOT
MUCH SHEAR ACROSS THE STATE WITH THE WEAK FLOW ALOFT...THOUGH WITH
CAPES BETWEEN 600-1200 J/KG...COULD SEE A FEW STRONGER STORMS
PRODUCING SMALL HAIL AND GUSTY WINDS. FURTHER WEST...DRY AIR ALOFT
HELPS TO MIX OUT DEW PTS IN THE 20S AND 30S ACROSS THE HIGHER
TERRAIN AND IMMEDIATE ADJACENT PLAINS THROUGH THE AFTERNOON.
HOWEVER...WITH STRONG SOLAR HEATING AND MID LEVEL LAPSE RATES AROUND
9C/KM...CANT RULE CU BUILDUPS AND AN ISOLATED HIGH BASED STORM
ACROSS THE EASTERN MTS. TEMPS ALOFT WARM A FEW DEGREES AND SHOULD
SEE HIGHS SOME 3-6F WARMER THAN YESTERDAY...MOST NOTABLE ACROSS THE
EASTERN PLAINS. SHOULD SEE STORMS DIMINISHING AND CLEARING SKIES
AFTER SUNSET...THOUGH WITH ANOTHER LOW LEVEL JET PROGGED ACROSS NEAR
THE WESTERN KANSAS BORDER...HAVE KEPT SLIGHT POPS ACROSS THE FAR SE
PLAINS THROUGH THE OVERNIGHT HOURS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 334 AM MDT FRI JUN 20 2014
.SATURDAY...A WEAK DISTURBANCE WILL PASS MOSTLY NORTH OF THE
REGION DURING THE AFTERNOON AND EARLY EVENING. SURFACE LOW
PRESSURE WILL DEVELOP OVER SOUTHEAST COLORADO...KEEPING MOST OF
THE EASTERLY LOW LEVEL FLOW NORTH OF THE CWA. MODEL SOUNDINGS SHOW
SOME MODEST CAPES DURING THE AFTERNOON AND EARLY EVENING OVER THE
PLAINS AND EASTERN MOUNTAINS. SUSPECT THE BEST LOW LEVEL MOISTURE
WILL STAY NORTH OF THE CWA. HAVE ISOLATED POPS OVER MUCH OF THE
REGIONS SATURDAY AFTERNOON AND EVENING. SPC KEEPS SLIGHT RISK OVER
NORTHEAST COLORADO ON SATURDAY. CONVECTION MAY TAP INTO BETTER LOW
LEVEL MOISTURE NEAR THE KANSAS BORDER AND INCREASED POPS TO SCATTERED
CATEGORY SATURDAY EVENING.
.SUNDAY...NEXT DISTURBANCE PASSES TO THE NORTH OF THE REGION
DURING THE DAY. BEST LOW LEVEL MOISTURE STAYS MOSTLY TO THE NORTH
OF THE CWA. INCREASED POPS TO SCATTERED OVER EL PASO AND KIOWA
COUNTIES AS COLD FRONT AND ASSOCIATED INCREASE IN LOW LEVEL
MOISTURE COULD BE OVER THESE AREAS. AS THE TROUGH PASSES TO THE
EAST OF THE REGION...PATTERN CHANGE BEGINS AS THE FLOW ALOFT
BECOMES NORTHWESTERLY. SOME MODELS HINT AT A SECONDARY DISTURBANCE
PASSING OVER THE REGION SUNDAY EVENING...AFTER THE COLD FRONT HAS
PASSED SOUTH OF THE CWA. WITH INCREASED LOW LEVEL MOISTURE...
THERE COULD BE A SECOND ROUND OF CONVECTION SUNDAY EVENING...AND
INCREASED POPS NEAR THE KANSAS BORDER SUNDAY EVENING.
.MONDAY THROUGH WEDNESDAY...NORTHWEST FLOW ALOFT DEVELOPS OVER THE
REGION...WITH WEAK EMBEDDED DISTURBANCES. AT THE SURFACE...HIGH
PRESSURE OVER THE NORTHERN PLAINS WILL KEEP LOW LEVEL EASTERLY
FLOW OVER THE EASTERN HALF OF THE CWA. THIS PATTERN IS PRONE TO
PERIODS OF SEVERE CONVECTIVE WEATHER...ESPECIALLY ON THE PLAINS.
AMOUNT...INTENSITY AND EXACT LOCATION OF STORMS WILL DEPEND ON
SUBTLE FEATURES WHICH ARE DIFFICULT TO FORECAST THIS FAR OUT.
MODELS HAVE 30 TO 50 KNOTS OF BULK SHEAR EACH DAY...WHICH IS
SUFFICIENT FOR SEVERE WEATHER. LOW LEVEL MOISTURE MAY MOVE AS FAR
WEST AS THE EASTERN MOUNTAINS...BUT NOT FURTHER WEST. AS A
RESULT...CHANCES FOR SIGNIFICANT RAINFALL OVER THE CONTINENTAL
DIVIDE REGION WILL BE LOW.
.THURSDAY...UPPER RIDGE STARTS TO MOVE EASTWARD WITH A GENERAL
DRYING AND WARMING TREND. GRIDS HAVE SOME ISOLATED POPS OVER THE
MOUNTAINS AND PORTIONS OF THE PLAINS...MOSTLY FOR SOME RESIDUAL
MOISTURE OVER THE REGION. --PGW--
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1115 AM MDT FRI JUN 20 2014
VFR CONDITIONS ANTICIPATED NEXT 24H AT ALL 3 TAF
SITES...KPUB...KALS AND KCOS. WINDS WILL BE DIURNALLY DRIVEN AND
LIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HODANISH
SHORT TERM...MW
LONG TERM...PGW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
428 AM MDT FRI JUN 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM MDT FRI JUN 20 2014
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING WEAK
WESTERLY FLOW ALOFT ACROSS THE REGION AS A MINOR DISTURBANCE (BEST
SEEN IN PV FIELDS) EMBEDDED WITHIN THE FLOW IS TRANSLATING ACROSS
THE STATE AT THIS TIME. THIS DISTURBANCE...ALONG WITH A LOW LEVEL JET
AND AMPLE LOW LEVEL MOISTURE...IS HELPING TO PRODUCE A FEW SHOWERS
AND THUNDERSTORMS ACROSS BENT...PROWERS AND KIOWA COUNTIES AT THIS
TIME. LATEST HI RES HRRR AND RUC MODELS...WHICH PICKED UP ON THIS
DEVELOPMENT LAST EVENING...MOVE THE DISTURBANCE AND STORMS EAST INTO
WESTERN KANSAS THROUGH 12Z FRI.
TODAY AND TONIGHT...MODELS KEEP WEAK WESTERLY FLOW ALOFT ACROSS THE
REGION THROUGH TONIGHT...AND WITH NO EVIDENT DISTURBANCE PROGGED
WITHIN THE FLOW...ANY STORMS TODAY LOOK TO BE INITIATED BY SOLAR
HEATING. WITH THAT SAID...LATEST MODELS REMAIN CONSISTENT WITH
DEVELOPING STORMS ACROSS THE FAR SE PLAINS...GENERALLY EAST OF A KIM
TO HASWELL LINE...WHERE CONVECTIVE TEMPS ARE IN THE LOW 90S AND DEW
PTS ARE PROGGED IN THE 40S TO LOWER 50S THIS AFTERNOON. THERE IS NOT
MUCH SHEAR ACROSS THE STATE WITH THE WEAK FLOW ALOFT...THOUGH WITH
CAPES BETWEEN 600-1200 J/KG...COULD SEE A FEW STRONGER STORMS
PRODUCING SMALL HAIL AND GUSTY WINDS. FURTHER WEST...DRY AIR ALOFT
HELPS TO MIX OUT DEW PTS IN THE 20S AND 30S ACROSS THE HIGHER
TERRAIN AND IMMEDIATE ADJACENT PLAINS THROUGH THE AFTERNOON.
HOWEVER...WITH STRONG SOLAR HEATING AND MID LEVEL LAPSE RATES AROUND
9C/KM...CANT RULE CU BUILDUPS AND AN ISOLATED HIGH BASED STORM
ACROSS THE EASTERN MTS. TEMPS ALOFT WARM A FEW DEGREES AND SHOULD
SEE HIGHS SOME 3-6F WARMER THAN YESTERDAY...MOST NOTABLE ACROSS THE
EASTERN PLAINS. SHOULD SEE STORMS DIMINISHING AND CLEARING SKIES
AFTER SUNSET...THOUGH WITH ANOTHER LOW LEVEL JET PROGGED ACROSS NEAR
THE WESTERN KANSAS BORDER...HAVE KEPT SLIGHT POPS ACROSS THE FAR SE
PLAINS THROUGH THE OVERNIGHT HOURS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 334 AM MDT FRI JUN 20 2014
.SATURDAY...A WEAK DISTURBANCE WILL PASS MOSTLY NORTH OF THE
REGION DURING THE AFTERNOON AND EARLY EVENING. SURFACE LOW
PRESSURE WILL DEVELOP OVER SOUTHEAST COLORADO...KEEPING MOST OF
THE EASTERLY LOW LEVEL FLOW NORTH OF THE CWA. MODEL SOUNDINGS SHOW
SOME MODEST CAPES DURING THE AFTERNOON AND EARLY EVENING OVER THE
PLAINS AND EASTERN MOUNTAINS. SUSPECT THE BEST LOW LEVEL MOISTURE
WILL STAY NORTH OF THE CWA. HAVE ISOLATED POPS OVER MUCH OF THE
REGIONS SATURDAY AFTERNOON AND EVENING. SPC KEEPS SLIGHT RISK OVER
NORTHEAST COLORADO ON SATURDAY. CONVECTION MAY TAP INTO BETTER LOW
LEVEL MOISTURE NEAR THE KANSAS BORDER AND INCREASED POPS TO SCATTERED
CATEGORY SATURDAY EVENING.
.SUNDAY...NEXT DISTURBANCE PASSES TO THE NORTH OF THE REGION
DURING THE DAY. BEST LOW LEVEL MOISTURE STAYS MOSTLY TO THE NORTH
OF THE CWA. INCREASED POPS TO SCATTERED OVER EL PASO AND KIOWA
COUNTIES AS COLD FRONT AND ASSOCIATED INCREASE IN LOW LEVEL
MOISTURE COULD BE OVER THESE AREAS. AS THE TROUGH PASSES TO THE
EAST OF THE REGION...PATTERN CHANGE BEGINS AS THE FLOW ALOFT
BECOMES NORTHWESTERLY. SOME MODELS HINT AT A SECONDARY DISTURBANCE
PASSING OVER THE REGION SUNDAY EVENING...AFTER THE COLD FRONT HAS
PASSED SOUTH OF THE CWA. WITH INCREASED LOW LEVEL MOISTURE...
THERE COULD BE A SECOND ROUND OF CONVECTION SUNDAY EVENING...AND
INCREASED POPS NEAR THE KANSAS BORDER SUNDAY EVENING.
.MONDAY THROUGH WEDNESDAY...NORTHWEST FLOW ALOFT DEVELOPS OVER THE
REGION...WITH WEAK EMBEDDED DISTURBANCES. AT THE SURFACE...HIGH
PRESSURE OVER THE NORTHERN PLAINS WILL KEEP LOW LEVEL EASTERLY
FLOW OVER THE EASTERN HALF OF THE CWA. THIS PATTERN IS PRONE TO
PERIODS OF SEVERE CONVECTIVE WEATHER...ESPECIALLY ON THE PLAINS.
AMOUNT...INTENSITY AND EXACT LOCATION OF STORMS WILL DEPEND ON
SUBTLE FEATURES WHICH ARE DIFFICULT TO FORECAST THIS FAR OUT.
MODELS HAVE 30 TO 50 KNOTS OF BULK SHEAR EACH DAY...WHICH IS
SUFFICIENT FOR SEVERE WEATHER. LOW LEVEL MOISTURE MAY MOVE AS FAR
WEST AS THE EASTERN MOUNTAINS...BUT NOT FURTHER WEST. AS A
RESULT...CHANCES FOR SIGNIFICANT RAINFALL OVER THE CONTINENTAL
DIVIDE REGION WILL BE LOW.
.THURSDAY...UPPER RIDGE STARTS TO MOVE EASTWARD WITH A GENERAL
DRYING AND WARMING TREND. GRIDS HAVE SOME ISOLATED POPS OVER THE
MOUNTAINS AND PORTIONS OF THE PLAINS...MOSTLY FOR SOME RESIDUAL
MOISTURE OVER THE REGION. --PGW--
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 334 AM MDT FRI JUN 20 2014
VFR CONDITIONS EXPECTED AT THE TAF SITES THROUGH THE NEXT 24 HOURS
WITH A GENERALLY LIGHT DIURNAL WIND REGIME. WILL SEE SOME CU
BUILDUPS ACROSS THE EASTERN MTS THIS AFTERNOON...WITH ISOLATED TO
SCATTERED THUNDERSTORMS POSSIBLE EAST OF KCOS AND KPUB DURING THE
AFTERNOON AND EVENING HOURS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MW
LONG TERM...PGW
AVIATION...MW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1113 PM MDT THU JUN 19 2014
.UPDATE...
ISSUED AT 1052 PM MDT THU JUN 19 2014
LATEST HIGH RES MODELS (HRRR...NSSL 4KM WRF...RAP13) SUGGEST
THUNDERSTORMS MAY DEVELOP ALONG THE NOSE OF THE LOW LEVEL JET
ACROSS THE FAR SOUTHEAST PLAINS. HRRR IS TARGETING KIOWA
COUNTY...WHILE NSSL 4KM WRF HAS THIS OCCURRING JUST NORTH IN
CHEYENNE COUNTY. CAPE INCREASES TO AROUND 1500 J/KG BETWEEN 06Z
AND 09Z IF THE LOW LEVEL JET CAN BREAK THROUGH THE CAP...THEN AN
ISOLATED STRONG THUNDERSTORM MIGHT BE POSSIBLY INTO EARLY FRIDAY
MORNING. THERE DOES APPEAR TO BE A SUBTLE SHORTWAVE EMBEDDED IN
THE FLOW ACROSS WESTERN CO WHICH WILL BE MOVING THROUGH EASTERN CO
OVERNIGHT...THOUGH FORCING LOOKS PRETTY WEAK. HAVE ADDED SOME
ISOLATED POPS ACROSS THE FAR EASTERN PLAINS THROUGH THE OVERNIGHT
HOURS TO ACCOUNT FOR THIS POTENTIAL.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 323 PM MDT THU JUN 19 2014
CURRENTLY...
MOSTLY CLEAR SKIES PREVAILED ACROSS THE REGION AT 2 PM...BEST
MOISTURE WAS DOWN ALONG THE CO/NM BORDER REGION WITH DWPTS IN THE
U40S AND L50S. TEMPS WERE QUITE A BIT COOLER THAN YDAY WITH LESS
WIND....WITH TEMPS IN THE U70S/L80S PLAINS.
REST OF TODAY...
BEST CHANCE OF ANY PRECIP TODAY WILL BE ALONG THE RATON MESA REGION.
WE COULD SEE SOME GUSTY WINDS AND SMALL HAIL AS PER LATEST SPC
PROBABILITIES. ANY CONVECTION WILL BE ISOLD.
TONIGHT...
OVERALL...MOSTLY CLEAR SKIES ANTICIPATED. T/TD SPREADS ALONG THE
BORDER ARE PRETTY LOW BUT THIS MSTR IS ONLY SKIN DEEP...SO DO NOT
EXPECT ANY SIGNIF LOW CLOUDS. FOG NOT LIKELY AS LLVL JET WILL BE
CRANKING TONIGHT OVER THE FAR E PLAINS.
TOMORROW...
BEST FORCING DURING THE AFTERNOON WILL BE ASSOCIATED WITH A TROUGH
LYING NE-SW ACROSS THE FAR SE PLAINS ROUGHLY FROM KLAA TO KIM.
MODELS ARE PERSISTENT AT BREAKING OUT SOME TSRA THIS AREA BY LATE IN
THE AFTERNOON OVER THIS REGION. SHEAR PRETTY WEAK SO ORGANIZED
CONVECTION NOT LIKELY...BUT STRONG WINDS AND SOME SMALL HAIL NOT
OUT OF THE QUESTION. OVER THE REMAINDER OF THE REGION IT WILL BE
PREDOMINANTLY DRY. IT WILL BE DRY TOMORROW WITH MAX TEMPS IN THE MID
90S ALONG THE LOWER ARK RVR VALLEY WITH U80S/L90S THE REST OF THE
PLAINS...70S AND 80S VALLEYS AND MTNS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 323 PM MDT THU JUN 19 2014
FRIDAY NIGHT AND SATURDAY...GENERAL W-SW FLOW ACROSS THE REGION WILL
KEEP HOT CONDITIONS IN PLACE...WITH DIURNAL ISOLATED CONVECTION FOR
THE MTS AND E PLAINS EACH EVE. FOR FRI EVE...CONVECTION IS FORECAST
TO REMAIN OVER THE SE CORNER...BUT THEN BECOME MORE WIDESPREAD FOR
SAT. LOOK FOR MAX TEMPS BOTHDAYS IN THE 90S FOR THE PLAINS AND 80S
FOR THE HIGH VALLEYS...WITH MILD READINGS OVERNIGHT.
SUNDAY THROUGH WEDNESDAY...A LOW PRES SYSTEM SLOWLY CROSSING CANADA
IS EXPECTED TO PUSH COLD AIR DOWN INTO THE ROCKY MT REGION BEGINNING
LATE SAT NIGHT. THIS PUSH OF COOL AND MORE MOIST AIR...IN ADDITION
TO THE UPPER FLOW SHIFTING TO A MORE W-NW DIRECTION...IS EXPECTED TO
BRING UPSLOPE CONDITIONS TO THE FORECAST AREA BEGINNING SUN
AFTN/EVE. THIS WILL MEAN SLIGHTLY COOLER TEMPS AND A FAIRLY GOOD
SHOT AT SOME PCPN FOR THE MTS AND E PLAINS LATE SUN THROUGH
WED...BEFORE THE UPPER PATTERN SHIFTS AGAIN. MAX TEMPS EACH DAY ARE
FORECAST TO BE IN THE 80S ACROSS THE PLAINS AND HIGH VALLEYS.
THURSDAY...LONG RANGE MODELS INDICATE THAT HIGH PRESSURE WILL START
TO STRENGTHEN OVER OLD MEXICO AND THE DESERT SW LATE WED...AND BE
FIRMLY IN PLACE FOR THE CWA ON THU. MAINLY DRY CONDITIONS ARE
FORECAST...ALONG WITH MAX TEMPS IN THE 90S FOR THE PLAINS AND IN
THE LOWER 80S FOR THE HIGH VALLEYS. MOORE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1052 PM MDT THU JUN 19 2014
VFR CONDITIONS EXPECTED AT THE TAF SITES THROUGH THE NEXT 24
HOURS. WINDS WILL GRADUALLY SHIFT OUT OF THE NORTH FOR KCOS AND
KPUB OVERNIGHT AT 5-10 KTS. WHILE NORTHWEST WINDS AROUND 10 KTS
AT KALS WINDS WILL GRADUALLY DECREASE OVERNIGHT. SOUTH TO
SOUTHEAST WINDS WILL INCREASE AGAIN ON FRIDAY AT 10-20 KTS.
ISOLATED TO SCATTERED THUNDERSTORMS WILL BE POSSIBLE TO THE EAST
OF KCOS AND KPUB DURING THE AFTERNOON. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...MOORE
AVIATION...KT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1035 PM EDT SAT JUN 21 2014
.SYNOPSIS...
HIGH PRESSURE BUILDS OVER THE AREA THROUGH THE WEEKEND...AND THEN
GIVES WAY TO AN APPROACHING FRONTAL SYSTEM OVER THE MID SECTION
OF THE COUNTRY EARLY NEXT WEEK. THE ASSOCIATED COLD FRONT WILL MOVE
ACROSS THE AREA WEDNESDAY INTO WEDNESDAY NIGHT. WEAK HIGH PRESSURE
WILL THEN RETURN FOR THE END OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THERE WERE SOME MINOR ADJUSTMENTS MADE WITH THIS UPDATE TO ACCOUNT
FOR THE INITIAL CONDITIONS. THE OVERNIGHT SKY FORECAST REMAINS A
CHALLENGE. 18Z GFS AND NAM WRF BOTH SHOW SOME HIGHER MOISTURE
MOVING INTO OR FORMING OVER THE AREA AROUND H85...OR 5000
FT...THIS EVENING AND OVERNIGHT. IT LOOKS LIKE THE TRI-STATE AREA
WILL BE ON THE NE PERIPHERY OF THE HIGHER MOISTURE WITH PERHAPS
THE HIGHEST CLOUD COVER BEING ACROSS NE NJ AND METRO NY...AND LESS
TO THE NE. THERE IS A GOOD DEAL OF UNCERTAINTY AND COULD VERY WELL
STAY MAINLY CLEAR. A PARTLY CLOUDY TO MOSTLY CLEAR FORECAST LOOKS
BEST RIGHT NOW. 01Z RUC ALSO INDICATING HIGHER MOISTURE AT THIS
LEVEL...BUT THE 00Z NAM HAS NOW BACKED OFF ON THIS IDEA...KEEPING
IT MOSTLY CLEAR. THIS COULD HAVE IMPACTS ON THE LOW TEMPERATURE
FORECAST OVERNIGHT...BUT DO NOT HAVE THE CONFIDENCE TO ADJUST
CLOUD COVER ONE WAY OR THE OTHER...ESPECIALLY SINCE THE 23Z NARRE IS
STILL INDICATING UP TO A 50 PERCENT CHANCE OF A CLOUD DECK LOWER
THAN 6K FT OVER THE SAME GENERAL AREA.
OTHERWISE...SFC HIGH PRES CONTINUES TO BUILD EAST TONIGHT. WINDS
WILL DIMINISH TO 5 MPH OR LESS.
LOWS TONIGHT WILL RANGE FROM THE LOW TO MID 60S IN/AROUND NYC TO
THE MID/UPPER 50S MOST ELSEWHERE. LOWS IN OUTLYING AREAS WILL DROP
INTO THE UPPER 40S DUE TO RADIATIONAL COOLING CONDS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
HIGH PRES CONTINUES TO DOMINATE THE AREA SUNDAY AND SUNDAY NIGHT.
ABUNDANT SUNSHINE ON TAP FOR SUNDAY WITH HIGH TEMPS A FEW DEGREES
WARMER THAN TODAY...GENERALLY TOPPING OFF IN THE MID TO UPPER
70S...EXCEPT FOR NYC AND AREAS WEST OF THE HUDSON RIVER...WHERE
HIGHS COULD TOP OFF IN THE LOW 80S.
CLEAR SKIES AND LIGHT WINDS ON TAP FOR SUNDAY NIGHT WITH LOWS ONCE
AGAIN RANGING FROM THE LOW TO MID 60S IN/AROUND NYC TO
THE MID/UPPER 50S MOST ELSEWHERE. LOWS IN OUTLYING AREAS WILL DROP
INTO THE UPPER 40S TO LOW 50S DUE TO RADIATIONAL COOLING CONDS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
THE UPPER AIR PATTERN WILL BE PROGRESSIVE THROUGH THE UPCOMING
WEEK WITH AN UPPER RIDGE EARLY IN THE WEEK MOVING ACROSS THE
EASTERN SEABOARD...FOLLOWED BY A MID WEEK SHORT WAVE TROF MOVING
FROM THE GREAT LAKES AND INTO THE NORTHEAST. THE LATTER OF WHICH
SENDS A WEAK COLD FRONT ACROSS THE REGION WED INTO WED NIGHT.
BEFORE AND AFTER THAT TIME...WEAK HIGH PRESSURE WILL BE IN PLACE.
NOT LOOKING FOR ANY EXTREMES THIS PERIOD WITH RESPECT TO BOTH
TEMPS AND RAINFALL.
HIGHS DURING THIS TIME WILL BE IN THE UPPER 70S TO AROUND 80 AT
THE COAST...AND IN THE LOW TO MID 80S JUST INLAND. LOWS WILL BE IN
THE 60S...WARMEST WED NIGHT ALONG AND AHEAD OF THE AFOREMENTIONED
COLD FRONT. CONDITIONS WILL BECOME INCREASINGLY HUMID AS DEW
POINTS RISE BACK INTO THE 60S TUE WITH A PROLONGED PERIOD OF
SOUTHERLY FLOW. WINDS WILL BRIEFLY GO W/NW THU BEHIND THE COLD
FRONT...BUT THIS LOOKS TO BE SHORT LIVED WITH NOT MUCH CHANGE IN
THE AIRMASS.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
WEAK HIGH PRES BUILDS TOWARDS THE AREA THROUGH SUNDAY.
VFR THROUGH PERIOD...ALTHOUGH COULD HAVE A BKN 6K FT DECK
OVERNIGHT...MAINLY NYC TERMINALS.
LIGHT SELY FLOW BECOMES VRB BY MIDNIGHT...AND BACKS TO
THE NE 5 KT OR LESS AFT 07Z. NE-E FLOW WILL GIVE WAY TO SEABREEZES
AGAIN ON SUN...DEVELOPING BETWEEN 14Z-16Z ALONG THE CT COAST
...16Z-18Z ALONG THE SOUTH SHORE OF LONG ISLAND AND MOVING INLAND
THROUGHOUT THE AFTN.
.OUTLOOK FOR 00Z MONDAY THROUGH THURSDAY...
.SUN NIGHT-TUE...VFR.
.TUE NIGHT-THU..MAINLY VFR. MVFR OR LOWER PSBL WITH SCT SHOWERS
AND TSTMS.
&&
.MARINE...
CONDITIONS REMAIN BELOW SMALL CRAFT ADVISORY LEVELS INTO THE START
OF THE NEW WEEK.
A GRADUALLY STRENGTHENING SOUTHERLY FLOW MON THROUGH WED COULD
PRODUCE MARGINAL SCA SEAS ON THE OCEAN WATERS TUE NIGHT INTO WED. A
WEAK W/NW FLOW FOLLOWS BEHIND A COLD FRONT FOR THU.
&&
.HYDROLOGY...
NO SIGNIFICANT WIDESPREAD RAINFALL IS ANTICIPATED THROUGH NEXT
WEEK. LOCALIZED HEAVY RAINFALL WITH THUNDERSTORMS ALONG AND AHEAD
OF THE COLD FRONT WED INTO WED NIGHT COULD RESULT IN URBAN...POOR
DRAINAGE FLOODING.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
907 PM EDT SAT JUN 21 2014
.UPDATE...
SCATTERED/NUMEROUS SHWRS AND TSTMS ARE MOVING ACROSS SE GA...WITH
ALL ACTIVITY ACROSS NE FL DISSIPATED. HIGH RESOLUTION MODELS VARY
WITH HANDLING OF THE CURRENT CLUSTER ACROSS SE GA...WITH THE LATEST
HRRR BRINGING THE ACTIVITY SOUTH ACROSS NE FL IN THE NEXT COUPLE
OF HOURS. HOWEVER...THE HRRR IS NOT INITIALIZED VERY WELL...DEPICTING
QUITE A BIT OF ACTIVITY ACROSS NE FL ALREADY. THE RUC13 IS NOT
MUCH BETTER. GIVEN CURRENT MOVEMENT AND SOME SIGNS OF A FEW CELLS
DEVELOPING ON THE SOUTHERN FLANK OF THE CURRENT ACTIVITY...WILL
BRING SOME POPS INTO NE FL OVER THE NEXT COUPLE OF HOURS...WITH
MOST ACTIVITY DECREASING BY MIDNIGHT OR SHORTLY THEREAFTER.
OTHERWISE...PARTLY CLOUDY SKIES WILL PREVAIL WITH LOWS NEAR NORMAL.
&&
.AVIATION...
A CLUSTER OF THUNDERSTORMS WILL MOVE EAST ACROSS SOUTHEAST GA...WHICH
IS EXPECTED TO AFFECT KSSI THIS EVENING. WHILE THIS CONVECTION IS NOT
EXPECTED TO GET INTO NORTHEAST FLORIDA...AN ISOLATED STORM GETTING
NEAR KJAX LATE THIS EVENING CAN NOT BE RULED OUT. OTHERWISE
PREVAILING VFR CONDITIONS ARE EXPECTED OVERNIGHT AND SUNDAY
MORNING. SCATTERED THUNDERSTORMS WILL DEVELOP DURING THE AFTERNOON
ON SUNDAY...WITH VCTS IN TAFS TO HIGHLIGHT THIS POTENTIAL.
&&
.MARINE...
SSW WINDS 10-15 KNOTS CURRENTLY WILL INCREASE A BIT OVERNIGHT AS A
WEAK SURFACE TROUGH NUDGES TO THE SOUTH. THUS...WILL RETAIN THE
CAUTION FOR THE OUTER LEGS TNGT.
RIP CURRENTS: LOW RISK THROUGH SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 72 95 72 94 / 50 50 40 50
SSI 76 89 75 88 / 20 60 60 60
JAX 74 94 73 93 / 20 60 60 50
SGJ 75 89 73 91 / 20 60 60 60
GNV 72 91 72 92 / 20 50 40 50
OCF 73 91 71 92 / 20 50 30 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
ALLEN/STRUBLE/GUILLET
AREA FORECAST DISCUSSION
NWS MIAMI FL
153 PM EDT FRI JUN 20 2014
.AVIATION...
CONVECTION HAS INITIATED ALMOST AS PLANNED, PERHAPS SLIGHTLY
EARLIER. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO CONTINUE TO
DEVELOP ACROSS SOUTH FLORIDA THROUGH THE AFTERNOON. SOME OF THEM
COULD BE STRONG, WITH HEAVY RAIN REDUCING VSBY AND LOWERING CIGS
TO TEMP IFR LEVELS. ALSO, THERE IS A POTENTIAL FOR STRONG
DOWNBURSTS AND NUMEROUS OUTFLOW BOUNDARIES. HAVE ADDED TEMPO
GROUPS TO ALL ATLANTIC TAF SITES THROUGH 21Z, ALTHOUGH THEY MAY
NEED TO BE EXTENDED A FEW HOURS. VFR CONDITIONS OVERNIGHT
TONIGHT, AND A GOOD CHANCE OF ANOTHER ROUND OF AFTERNOON
CONVECTION TOMORROW AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 944 AM EDT FRI JUN 20 2014/
UPDATE...
WEAK MID/UPPER LEVEL TROUGH OF LOW PRESSURE ALONG WITH A WEAK
SURFACE TROUGH REMAIN NEARLY STATIONARY THIS MORNING ALONG THE
EASTERN PENINSULA COAST. FORECAST MODELS ALL INDICATE THESE
TROUGH BOUNDARIES WILL MOVE LITTLE THROUGH THE DAY. THE 12Z MFL
SOUNDING SHOWS A SIMILAR STATE TO THE ATMOSPHERE AS 24 HOURS AGO
WITH A VERY MOIST AND UNSTABLE ENVIRONMENT. THE PWAT IS AT 1.9
INCHES WITH THE MOST UNSTABLE CAPE SHOWING OVER 2000 J/KG ALONG
WITH A LIGHT WESTERLY STEERING FLOW. THE MID LEVEL LAPSE RATES
LIKE YESTERDAY ARE NOT TERRIBLY IMPRESSIVE SO WIDESPREAD SEVERE
STORMS ARE NOT EXPECTED. HOWEVER, THE SKY IS STARTING OUT THIS
MORNING NEARLY CLOUD FREE SO THERE WILL AGAIN BE ABUNDANT DIURNAL
HEATING WHICH WILL SET THE STAGE FOR STRONG UPDRAFTS BY LATE THIS
MORNING AS SURFACE TEMPERATURES REACH THE MID AND UPPER 80S. ALL
OF THIS SAID, THE FORECAST APPEARS TO BE RIGHT ON TRACK WITH THE
HIGHEST CHANCES ALONG THE EAST COAST WITH STRONG THUNDERSTORMS
LIKELY AND THERE IS ALWAYS THE OUTSIDE CHANCE OF AN ISOLATED
SEVERE STORM WITH THE PRIMARY CONCERN BEING THE STRONG WIND GUSTS.
KOB
PREV DISCUSSION... /ISSUED 348 AM EDT FRI JUN 20 2014/
DISCUSSION...A WEAK LOW IS CENTERED OFF THE COAST AT CAPE
CANAVERAL. THIS IS LEADING TO A LIGHT MEAN WESTERLY STEERING FLOW
ACROSS SOUTH FLORIDA. ANOTHER ACTIVE DAY OF TSTORMS IS EXPECTED
INTERIOR TO THE EAST COAST METRO AREAS AS A DEVELOPING ATLANTIC
SEA BREEZE THIS AFTERNOON BUMPS UP AGAINST THE OPPOSING MEAN
WESTERLY WIND FLOW. MOISTURE AND INSTABILITY LOOKS MORE THAN
SUFFICIENT TO GET THINGS GOING SO THREW OUT THE LOW GFS MOS POP
NUMBERS WHICH LOOK WAY TOO LOW. SIDED WITH NAM MOS AND HRRR WHICH
SHOWS ACTIVE CONVECTION FOCUSED EAST COAST METRO.
LATEST HRRR REALLY FOCUSES ACTIVITY ACROSS THE FORT LAUDERDALE
AND MIAMI METRO AREAS LATE THIS AFTERNOON...WITH LESS ACTIVITY AT
THE PALM BEACHES. NAM12 THOUGH FOCUSES CONVECTION FROM THE LAKE
TO THE PALM BEACHES. ALTHOUGH I`M CONFIDENT TSTORMS WILL FOCUS
EAST COAST METRO, THE EXACT PLACEMENT OF CONVECTION IS UNCERTAIN,
SO DID NOT GET FANCY AND PLACED LIKELY POPS UP AND DOWN THE SE
FLORIDA COAST THIS AFTERNOON.
MAIN CONCERN WILL BE LOCALLY HEAVY RAINFALL AND STRONG WIND GUSTS.
LOCALIZED URBAN FLOODING WILL BE POSSIBLE WHERE THE STRONGEST
STORMS HIT...ESPECIALLY IF THEY HIT ACROSS AREAS WHICH SAW HEAVY
RAINFALL YESTERDAY. WILL HIGHLIGHT THESE POTENTIAL HAZARDS IN THE
MORNING HAZARDOUS WEATHER OUTLOOK.
A TYPICAL SUMMERTIME PATTERN IS EXPECTED OVER THE UPCOMING WEEKEND
AND NEXT WEEK WITH SCATTERED AFTERNOON TSTORMS EXPECTED TO DEVELOP
EACH DAY. NO MAJOR SYNOPTIC SCALE FEATURES OF NOTE. THE FOCUS
OF STORMS THIS WEEKEND STILL LOOKS TO FAVOR THE EASTERN HALF OF
THE AREA...THEN FAVORING INTERIOR AREAS MOST OF NEXT WEEK AS THE
RIDGE BUILDS IN AND WE GET INTO MORE OF A SE WIND FLOW PATTERN.
GFS AND ECMWF CONTINUE TO DIFFER WITH RESPECT TO MOISTURE NEXT
WEEK WITH ECMWF DRYING THINGS OUT MORE SO THAN THE GFS. GFS DOES
SEEM TOO STRONG WITH AN INVERTED TROUGH MOVING OUT OF THE CARIB.
IT`S HAD A STRONG BIAS ALL SEASON...SO NOT BUYING THIS. HAVE GONE
WITH CHANCE POPS MOST LOCALES EACH DAY THROUGH NEXT WEEK...AS SEE
NO REASON TO DEVIATE FROM THIS. /GREGORIA
MARINE...LIGHT WINDS WILL PREVAIL LEADING TO A CONTINUATION OF
LOW SEAS. MAIN HAZARD WILL BE LIGHTNING AND LOCALLY GUSTY WINDS IN
AND NEAR TSTORMS. /GREGORIA
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 89 76 90 / 40 50 20 20
FORT LAUDERDALE 75 88 78 90 / 40 50 20 20
MIAMI 74 91 76 90 / 40 50 20 20
NAPLES 73 88 74 89 / 20 30 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....57/DG
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
944 AM EDT FRI JUN 20 2014
.UPDATE...
WEAK MID/UPPER LEVEL TROUGH OF LOW PRESSURE ALONG WITH A WEAK
SURFACE TROUGH REMAIN NEARLY STATIONARY THIS MORNING ALONG THE
EASTERN PENINSULA COAST. FORECAST MODELS ALL INDICATE THESE
TROUGH BOUNDARIES WILL MOVE LITTLE THROUGH THE DAY. THE 12Z MFL
SOUNDING SHOWS A SIMILAR STATE TO THE ATMOSPHERE AS 24 HOURS AGO
WITH A VERY MOIST AND UNSTABLE ENVIRONMENT. THE PWAT IS AT 1.9
INCHES WITH THE MOST UNSTABLE CAPE SHOWING OVER 2000 J/KG ALONG
WITH A LIGHT WESTERLY STEERING FLOW. THE MID LEVEL LAPSE RATES
LIKE YESTERDAY ARE NOT TERRIBLY IMPRESSIVE SO WIDESPREAD SEVERE
STORMS ARE NOT EXPECTED. HOWEVER, THE SKY IS STARTING OUT THIS
MORNING NEARLY CLOUD FREE SO THERE WILL AGAIN BE ABUNDANT DIURNAL
HEATING WHICH WILL SET THE STAGE FOR STRONG UPDRAFTS BY LATE THIS
MORNING AS SURFACE TEMPERATURES REACH THE MID AND UPPER 80S. ALL
OF THIS SAID, THE FORECAST APPEARS TO BE RIGHT ON TRACK WITH THE
HIGHEST CHANCES ALONG THE EAST COAST WITH STRONG THUNDERSTORMS
LIKELY AND THERE IS ALWAYS THE OUTSIDE CHANCE OF AN ISOLATED
SEVERE STORM WITH THE PRIMARY CONCERN BEING THE STRONG WIND GUSTS.
KOB
&&
.PREV DISCUSSION... /ISSUED 801 AM EDT FRI JUN 20 2014/
AVIATION...
WEAK LOW PRESSURE OVER FLORIDA WILL CONTINUE TO BRING UNSETTLED
WEATHER TO THE AREA. ALSO, HIGH PRESSURE TO THE NORTHEAST HAS
WEAKENED, WHICH IS ALLOWING FOR A MORE WESTERLY FLOW TODAY. THIS
WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS TO THE
ATLANTIC TAF SITES THIS AFTERNOON, ESPECIALLY ONCE THE SEA BREEZE
IS ABLE TO DEVELOP. ALONG THE GULF COAST, WITH THE WESTERLY FLOW,
THE GULF BREEZE WILL BE ENHANCED, KEEPING MOST OF THE CONVECTIVE
ACTIVITY EAST OF KAPF. SO, WITH UNCERTAINTY AS TO THE TIMING AND
THE EXACT LOCATION OF CONVECTIVE CELLS, HAVE ONLY VCTS IN THE TAFS
THIS AFTERNOON FOR THE EASTERN TAF SITES. CONDITIONS SHOULD
IMPROVE AFTER 00Z.
PREV DISCUSSION... /ISSUED 348 AM EDT FRI JUN 20 2014/
DISCUSSION...A WEAK LOW IS CENTERED OFF THE COAST AT CAPE
CANAVERAL. THIS IS LEADING TO A LIGHT MEAN WESTERLY STEERING FLOW
ACROSS SOUTH FLORIDA. ANOTHER ACTIVE DAY OF TSTORMS IS EXPECTED
INTERIOR TO THE EAST COAST METRO AREAS AS A DEVELOPING ATLANTIC
SEA BREEZE THIS AFTERNOON BUMPS UP AGAINST THE OPPOSING MEAN
WESTERLY WIND FLOW. MOISTURE AND INSTABILITY LOOKS MORE THAN
SUFFICIENT TO GET THINGS GOING SO THREW OUT THE LOW GFS MOS POP
NUMBERS WHICH LOOK WAY TOO LOW. SIDED WITH NAM MOS AND HRRR WHICH
SHOWS ACTIVE CONVECTION FOCUSED EAST COAST METRO.
LATEST HRRR REALLY FOCUSES ACTIVITY ACROSS THE FORT LAUDERDALE
AND MIAMI METRO AREAS LATE THIS AFTERNOON...WITH LESS ACTIVITY AT
THE PALM BEACHES. NAM12 THOUGH FOCUSES CONVECTION FROM THE LAKE
TO THE PALM BEACHES. ALTHOUGH I`M CONFIDENT TSTORMS WILL FOCUS
EAST COAST METRO, THE EXACT PLACEMENT OF CONVECTION IS UNCERTAIN,
SO DID NOT GET FANCY AND PLACED LIKELY POPS UP AND DOWN THE SE
FLORIDA COAST THIS AFTERNOON.
MAIN CONCERN WILL BE LOCALLY HEAVY RAINFALL AND STRONG WIND GUSTS.
LOCALIZED URBAN FLOODING WILL BE POSSIBLE WHERE THE STRONGEST
STORMS HIT...ESPECIALLY IF THEY HIT ACROSS AREAS WHICH SAW HEAVY
RAINFALL YESTERDAY. WILL HIGHLIGHT THESE POTENTIAL HAZARDS IN THE
MORNING HAZARDOUS WEATHER OUTLOOK.
A TYPICAL SUMMERTIME PATTERN IS EXPECTED OVER THE UPCOMING WEEKEND
AND NEXT WEEK WITH SCATTERED AFTERNOON TSTORMS EXPECTED TO DEVELOP
EACH DAY. NO MAJOR SYNOPTIC SCALE FEATURES OF NOTE. THE FOCUS
OF STORMS THIS WEEKEND STILL LOOKS TO FAVOR THE EASTERN HALF OF
THE AREA...THEN FAVORING INTERIOR AREAS MOST OF NEXT WEEK AS THE
RIDGE BUILDS IN AND WE GET INTO MORE OF A SE WIND FLOW PATTERN.
GFS AND ECMWF CONTINUE TO DIFFER WITH RESPECT TO MOISTURE NEXT
WEEK WITH ECMWF DRYING THINGS OUT MORE SO THAN THE GFS. GFS DOES
SEEM TOO STRONG WITH AN INVERTED TROUGH MOVING OUT OF THE CARIB.
IT`S HAD A STRONG BIAS ALL SEASON...SO NOT BUYING THIS. HAVE GONE
WITH CHANCE POPS MOST LOCALES EACH DAY THROUGH NEXT WEEK...AS SEE
NO REASON TO DEVIATE FROM THIS. /GREGORIA
MARINE...LIGHT WINDS WILL PREVAIL LEADING TO A CONTINUATION OF
LOW SEAS. MAIN HAZARD WILL BE LIGHTNING AND LOCALLY GUSTY WINDS IN
AND NEAR TSTORMS. /GREGORIA
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 73 89 76 / 70 40 50 20
FORT LAUDERDALE 87 75 88 78 / 70 40 50 20
MIAMI 88 74 91 76 / 70 40 50 20
NAPLES 88 73 88 74 / 20 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
801 AM EDT FRI JUN 20 2014
.AVIATION...
WEAK LOW PRESSURE OVER FLORIDA WILL CONTINUE TO BRING UNSETTLED
WEATHER TO THE AREA. ALSO, HIGH PRESSURE TO THE NORTHEAST HAS
WEAKENED, WHICH IS ALLOWING FOR A MORE WESTERLY FLOW TODAY. THIS
WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS TO THE
ATLANTIC TAF SITES THIS AFTERNOON, ESPECIALLY ONCE THE SEA BREEZE
IS ABLE TO DEVELOP. ALONG THE GULF COAST, WITH THE WESTERLY FLOW,
THE GULF BREEZE WILL BE ENHANCED, KEEPING MOST OF THE CONVECTIVE
ACTIVITY EAST OF KAPF. SO, WITH UNCERTAINTY AS TO THE TIMING AND
THE EXACT LOCATION OF CONVECTIVE CELLS, HAVE ONLY VCTS IN THE TAFS
THIS AFTERNOON FOR THE EASTERN TAF SITES. CONDITIONS SHOULD
IMPROVE AFTER 00Z.
&&
.PREV DISCUSSION... /ISSUED 348 AM EDT FRI JUN 20 2014/
DISCUSSION...A WEAK LOW IS CENTERED OFF THE COAST AT CAPE
CANAVERAL. THIS IS LEADING TO A LIGHT MEAN WESTERLY STEERING FLOW
ACROSS SOUTH FLORIDA. ANOTHER ACTIVE DAY OF TSTORMS IS EXPECTED
INTERIOR TO THE EAST COAST METRO AREAS AS A DEVELOPING ATLANTIC
SEA BREEZE THIS AFTERNOON BUMPS UP AGAINST THE OPPOSING MEAN
WESTERLY WIND FLOW. MOISTURE AND INSTABILITY LOOKS MORE THAN
SUFFICIENT TO GET THINGS GOING SO THREW OUT THE LOW GFS MOS POP
NUMBERS WHICH LOOK WAY TOO LOW. SIDED WITH NAM MOS AND HRRR WHICH
SHOWS ACTIVE CONVECTION FOCUSED EAST COAST METRO.
LATEST HRRR REALLY FOCUSES ACTIVITY ACROSS THE FORT LAUDERDALE
AND MIAMI METRO AREAS LATE THIS AFTERNOON...WITH LESS ACTIVITY AT
THE PALM BEACHES. NAM12 THOUGH FOCUSES CONVECTION FROM THE LAKE
TO THE PALM BEACHES. ALTHOUGH I`M CONFIDENT TSTORMS WILL FOCUS
EAST COAST METRO, THE EXACT PLACEMENT OF CONVECTION IS UNCERTAIN,
SO DID NOT GET FANCY AND PLACED LIKELY POPS UP AND DOWN THE SE
FLORIDA COAST THIS AFTERNOON.
MAIN CONCERN WILL BE LOCALLY HEAVY RAINFALL AND STRONG WIND GUSTS.
LOCALIZED URBAN FLOODING WILL BE POSSIBLE WHERE THE STRONGEST
STORMS HIT...ESPECIALLY IF THEY HIT ACROSS AREAS WHICH SAW HEAVY
RAINFALL YESTERDAY. WILL HIGHLIGHT THESE POTENTIAL HAZARDS IN THE
MORNING HAZARDOUS WEATHER OUTLOOK.
A TYPICAL SUMMERTIME PATTERN IS EXPECTED OVER THE UPCOMING WEEKEND
AND NEXT WEEK WITH SCATTERED AFTERNOON TSTORMS EXPECTED TO DEVELOP
EACH DAY. NO MAJOR SYNOPTIC SCALE FEATURES OF NOTE. THE FOCUS
OF STORMS THIS WEEKEND STILL LOOKS TO FAVOR THE EASTERN HALF OF
THE AREA...THEN FAVORING INTERIOR AREAS MOST OF NEXT WEEK AS THE
RIDGE BUILDS IN AND WE GET INTO MORE OF A SE WIND FLOW PATTERN.
GFS AND ECMWF CONTINUE TO DIFFER WITH RESPECT TO MOISTURE NEXT
WEEK WITH ECMWF DRYING THINGS OUT MORE SO THAN THE GFS. GFS DOES
SEEM TOO STRONG WITH AN INVERTED TROUGH MOVING OUT OF THE CARIB.
IT`S HAD A STRONG BIAS ALL SEASON...SO NOT BUYING THIS. HAVE GONE
WITH CHANCE POPS MOST LOCALES EACH DAY THROUGH NEXT WEEK...AS SEE
NO REASON TO DEVIATE FROM THIS. /GREGORIA
MARINE...LIGHT WINDS WILL PREVAIL LEADING TO A CONTINUATION OF
LOW SEAS. MAIN HAZARD WILL BE LIGHTNING AND LOCALLY GUSTY WINDS IN
AND NEAR TSTORMS. /GREGORIA
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 73 89 76 / 70 40 50 20
FORT LAUDERDALE 87 75 88 78 / 70 40 50 20
MIAMI 88 74 91 76 / 70 40 50 20
NAPLES 88 73 88 74 / 20 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...57/DG
LONG TERM....57/DG
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS MIAMI FL
348 AM EDT FRI JUN 20 2014
.DISCUSSION...A WEAK LOW IS CENTERED OFF THE COAST AT CAPE
CANAVERAL. THIS IS LEADING TO A LIGHT MEAN WESTERLY STEERING FLOW
ACROSS SOUTH FLORIDA. ANOTHER ACTIVE DAY OF TSTORMS IS EXPECTED
INTERIOR TO THE EAST COAST METRO AREAS AS A DEVELOPING ATLANTIC
SEA BREEZE THIS AFTERNOON BUMPS UP AGAINST THE OPPOSING MEAN
WESTERLY WIND FLOW. MOISTURE AND INSTABILITY LOOKS MORE THAN
SUFFICIENT TO GET THINGS GOING SO THREW OUT THE LOW GFS MOS POP
NUMBERS WHICH LOOK WAY TOO LOW. SIDED WITH NAM MOS AND HRRR WHICH
SHOWS ACTIVE CONVECTION FOCUSED EAST COAST METRO.
LATEST HRRR REALLY FOCUSES ACTIVITY ACROSS THE FORT LAUDERDALE
AND MIAMI METRO AREAS LATE THIS AFTERNOON...WITH LESS ACTIVITY AT
THE PALM BEACHES. NAM12 THOUGH FOCUSES CONVECTION FROM THE LAKE
TO THE PALM BEACHES. ALTHOUGH I`M CONFIDENT TSTORMS WILL FOCUS
EAST COAST METRO, THE EXACT PLACEMENT OF CONVECTION IS UNCERTAIN,
SO DID NOT GET FANCY AND PLACED LIKELY POPS UP AND DOWN THE SE
FLORIDA COAST THIS AFTERNOON.
MAIN CONCERN WILL BE LOCALLY HEAVY RAINFALL AND STRONG WIND GUSTS.
LOCALIZED URBAN FLOODING WILL BE POSSIBLE WHERE THE STRONGEST
STORMS HIT...ESPECIALLY IF THEY HIT ACROSS AREAS WHICH SAW HEAVY
RAINFALL YESTERDAY. WILL HIGHLIGHT THESE POTENTIAL HAZARDS IN THE
MORNING HAZARDOUS WEATHER OUTLOOK.
A TYPICAL SUMMERTIME PATTERN IS EXPECTED OVER THE UPCOMING WEEKEND
AND NEXT WEEK WITH SCATTERED AFTERNOON TSTORMS EXPECTED TO DEVELOP
EACH DAY. NO MAJOR SYNOPTIC SCALE FEATURES OF NOTE. THE FOCUS
OF STORMS THIS WEEKEND STILL LOOKS TO FAVOR THE EASTERN HALF OF
THE AREA...THEN FAVORING INTERIOR AREAS MOST OF NEXT WEEK AS THE
RIDGE BUILDS IN AND WE GET INTO MORE OF A SE WIND FLOW PATTERN.
GFS AND ECMWF CONTINUE TO DIFFER WITH RESPECT TO MOISTURE NEXT
WEEK WITH ECMWF DRYING THINGS OUT MORE SO THAN THE GFS. GFS DOES
SEEM TOO STRONG WITH AN INVERTED TROUGH MOVING OUT OF THE CARIB.
IT`S HAD A STRONG BIAS ALL SEASON...SO NOT BUYING THIS. HAVE GONE
WITH CHANCE POPS MOST LOCALES EACH DAY THROUGH NEXT WEEK...AS SEE
NO REASON TO DEVIATE FROM THIS. /GREGORIA
&&
.MARINE...LIGHT WINDS WILL PREVAIL LEADING TO A CONTINUATION OF
LOW SEAS. MAIN HAZARD WILL BE LIGHTNING AND LOCALLY GUSTY WINDS IN
AND NEAR TSTORMS. /GREGORIA
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 73 89 76 / 70 40 50 20
FORT LAUDERDALE 87 75 88 78 / 70 40 50 20
MIAMI 88 74 91 76 / 70 40 50 20
NAPLES 88 73 88 74 / 20 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
245 PM EDT FRI JUN 20 2014
.SYNOPSIS...
A SURFACE TROUGH WILL REMAIN ACROSS THE AREA THROUGH SUNDAY AS
UPPER LEVEL RIDGING SLIDES WESTWARD. ABOVE NORMAL TEMPERATURES
AND THE CHANCE FOR THUNDERSTORMS WILL CONTINUE INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...SHORTWAVE MOVING THROUGH THE MOUNTAINS CURRENTLY
PRODUCING SCATTERED SHOWERS AND THUNDERSTORMS NEAR THE FOOTHILLS.
THIS SHORTWAVE AND ASSOCIATED ACTIVITY WILL CONTINUE TO MOVE
EASTWARD THROUGH THE AFTERNOON AND EVENING...MOVING INTO A
MODERATELY UNSTABLE AIRMASS. BEST MOISTURE FIELDS ON SATELLITE
APPEAR TO BE ACROSS THE NORTHERN MIDLANDS...WITH ANOTHER ON ACROSS
THE EXTREME SOUTHERN PORTIONS OF THE SAVANNAH RIVER REGION. EXPECT
TO SEE ADDITIONAL THUNDERSTORM DEVELOPMENT IN BOTH OF THOSE AREAS
INTO THE EVENING. AS WITH THE PREVIOUS FEW DAYS...ANY STORMS THAT
DEVELOP COULD BECOME SEVERE WITH DAMAGING WIND AND HEAVY RAIN
THREATS. LOCAL MODEL ALONG WITH THE LATEST HRRR SHOWING SCATTERED
CONVECTION DEVELOPING LATE IN THE AFTERNOON...LASTING WELL INTO
THE EVENING. THIS AGREES WITH THE SPCWRF. WILL GO WITH 20 TO 40
PERCENT POPS FOR THE LATE AFTERNOON AND EVENING.
TONIGHT...CONVECTION WILL DIMINISH BY MIDNIGHT. HOWEVER...THE
AIRMASS WILL REMAIN UNSTABLE WITH PERHAPS A WEAK SHORT WAVE. EVEN
THOUGH CANNOT TOTALLY RULE OUT A SHOWER OR THUNDERSTORM
OVERNIGHT...ELECTED TO GO WITH MAINLY DRY FORECAST LATE TONIGHT
THROUGH EARLY MORNING. KEPT OVERNIGHT LOWS IN THE LOWER 70S...PER
PERSISTENCE.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
REMAINS OF A FRONTAL BOUNDARY WILL BE ACROSS THE MID ATLANTIC
STATES SATURDAY MORNING WITH A WEAK LOW FORMING OVER NC SATURDAY
AFTERNOON. AS THE LOW FORMS THE FRONTAL BOUNDARY WILL DROP FURTHER
SOUTH AND INTO THE FORECAST AREA LATE SATURDAY AFTERNOON AND
EVENING. THE FRONT WILL STALL JUST SOUTH OF THE FORECAST AREA
SATURDAY NIGHT AND REMAIN QUASI-STATIONARY THROUGH SUNDAY NIGHT.
MODEL SOUNDINGS SHOW MODERATE INSTABILITY THROUGH THE DAY SATURDAY
AND WITH THE FRONT ACTING AS A TRIGGER MECHANISM SHOWERS AND
THUNDERSTORMS WILL DEVELOP DURING THE AFTERNOON AND EVENING HOURS.
ALTHOUGH THE POTENTIAL FOR LARGE HAIL WILL REMAIN LOW...FREEZING
AND WET BULB ZERO AROUND 15 KFT AND 12 KFT RESPECTIVELY...WITH
DRIER AIR IN THE MID LEVELS THERE WILL BE POTENTIAL FOR STRONG
AND DAMAGING WINDS. THE CONVECTIVE POTENTIAL WILL BE A BIT LOWER
ON SUNDAY AS THE FRONT WILL BE SOUTH OF THE AREA WITH DRIER AIR
SLOWLY MOVING INTO THE MID AND UPPER LEVELS THROUGH THE DAY.
TEMPERATURES WILL BE IN THE MIDDLE TO UPPER 90S ON SATURDAY WITH
LOWER TO MIDDLE 90S SUNDAY...WITH OVERNIGHT LOWS IN THE UPPER 60S
TO LOWER 70S EACH NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
MODELS REMAIN IN GOOD AGREEMENT THROUGH THE WEEKEND WITH THE GFS
TAKING A MORE AGGRESSIVE APPROACH IN OPENING THE GULF NEXT WEEK.
STALLED FRONTAL BOUNDARY WILL SLOWLY BEGIN RETURNING NORTHWARD ON
MONDAY AS THE NEXT LOW PRESSURE SYSTEM MOVES INTO THE GREAT LAKES
REGION. BY TUESDAY EVENING THE FRONT WILL BE ACROSS SOUTHERN NC
WITH A WEAK PRESSURE TROUGH LINGERING OVER THE EASTERN US THROUGH
THURSDAY. DURING THIS PERIOD THE GFS USHERS MOISTURE NORTHWARD
FROM THE GULF WHILE THE ECMWF IS LESS AGGRESSIVE WITH THE
MOISTURE. HAVE REMAINED WITH CHANCE POPS THROUGH THE LONG TERM AS
THE FRONTAL BOUNDARY MEANDERING ACROSS THE REGION WILL ACT AS A
TRIGGER MECHANISM...AND HAVE NOT GONE WITH THE GFS MOISTURE PLUME
AS THIS IS A SIGNIFICANT CHANGE FROM THE LAST RUN. TEMPERATURES
THROUGH THE LONG TERM WILL BE NEAR TO SLIGHTLY ABOVE NORMAL WITH
DAYTIME HIGHS IN THE LOWER 90S AND OVERNIGHT LOWS IN THE UPPER 60S
TO LOWER 70S.
LONG
TERM WITH SOME MINOR DIFFERENCES IN TIMING AND INTENSITY. WEAK LOW
PRESSURE WILL SLIDE OFFSHORE OF THE MID ATLANTIC STATES ON SUNDAY
WITH THE REMAINS OF THE FRONT PUSHING THROUGH THE FORECAST AREA ON
SUNDAY THEN STALLING JUST SOUTH OF THE AREA SUNDAY NIGHT THROUGH
EARLY TUESDAY. THE FRONT WILL MEANDER NORTHWARD ON TUESDAY AS THE
NEXT LOW PRESSURE SYSTEM CROSSES THE GREAT LAKES. AS THE LOW
TRACKS FURTHER EASTWARD WEDNESDAY AND THURSDAY THE COLD FRONT WILL
CROSS INTO THE EASTERN US THEN STALL ACROSS THE AREA. THIS SERIES
OF FEATURES WILL KEEP CHANCES OF SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH THE LONG TERM. TEMPERATURES THROUGH THE LONG TERM
WILL BE NEAR TO SLIGHTLY ABOVE NORMAL WITH DAYTIME HIGHS IN THE
LOWER TO MIDDLE 90S AND OVERNIGHT LOWS IN THE LOWER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
GENERALLY VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE
PERIOD.
SKIES PARTLY CLOUDY WITH BASES AROUND 5KFT THROUGH THE AFTERNOON.
WINDS WILL GENERALLY REMAIN LIGHT AND SOMEWHAT VARIABLE. STRONG
SURFACE HEATING COMBINED WITH A SHORTWAVE MOVING OUT OF THE
CENTRAL APPALACHIANS WILL PROVIDE A FOCUS FOR SOME AFTERNOON
CONVECTION. CONVECTION SHOULD BE SCATTERED. DUE TO UNCERTAINTY IN
TIMING...DEVELOPMENT...AND EVENTUAL MOVEMENT OF STORMS...WILL NOT
INCLUDE IN THE FORECAST AT THIS TIME. UPDATES WILL BE REQUIRED IF
CONVECTION IS ABLE TO APPROACH TERMINALS LATE IN THE AFTERNOON. DEBRIS
CLOUDS THIS EVENING COULD INHIBIT FOG DEVELOPMENT SATURDAY MORNING.
EXTENDED AVIATION OUTLOOK...EARLY MORNING MVFR/IFR FOG POSSIBLE
EACH DAY...MAINLY AT FOG PRONE SITES AGS/OGB. SCATTERED DIURNAL
THUNDERSTORMS EXPECTED EACH AFTERNOON AND EVENING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
202 PM EDT FRI JUN 20 2014
.SYNOPSIS...
A SURFACE TROUGH WILL REMAIN ACROSS THE AREA THROUGH SUNDAY AS
UPPER LEVEL RIDGING SLIDES WESTWARD. ABOVE NORMAL TEMPERATURES
AND THE CHANCE FOR THUNDERSTORMS WILL CONTINUE INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...SHORTWAVE MOVING THROUGH THE MOUNTAINS CURRENTLY
PRODUCING SCATTERED SHOWERS AND THUNDERSTORMS NEAR THE FOOTHILLS.
THIS SHORTWAVE AND ASSOCIATED ACTIVITY WILL CONTINUE TO MOVE
EASTWARD THROUGH THE AFTERNOON AND EVENING...MOVING INTO A
MODERATELY UNSTABLE AIRMASS. BEST MOISTURE FIELDS ON SATELLITE
APPEAR TO BE ACROSS THE NORTHERN MIDLANDS...WITH ANOTHER ON ACROSS
THE EXTREME SOUTHERN PORTIONS OF THE SAVANNAH RIVER REGION. EXPECT
TO SEE ADDITIONAL THUNDERSTORM DEVELOPMENT IN BOTH OF THOSE AREAS
INTO THE EVENING. AS WITH THE PREVIOUS FEW DAYS...ANY STORMS THAT
DEVELOP COULD BECOME SEVERE WITH DAMAGING WIND AND HEAVY RAIN
THREATS. LOCAL MODEL ALONG WITH THE LATEST HRRR SHOWING SCATTERED
CONVECTION DEVELOPING LATE IN THE AFTERNOON...LASTING WELL INTO
THE EVENING. THIS AGREES WITH THE SPCWRF. WILL GO WITH 20 TO 40
PERCENT POPS FOR THE LATE AFTERNOON AND EVENING.
TONIGHT...CONVECTION WILL DIMINISH BY MIDNIGHT. HOWEVER...THE
AIRMASS WILL REMAIN UNSTABLE WITH PERHAPS A WEAK SHORT WAVE. EVEN
THOUGH CANNOT TOTALLY RULE OUT A SHOWER OR THUNDERSTORM
OVERNIGHT...ELECTED TO GO WITH MAINLY DRY FORECAST LATE TONIGHT
THROUGH EARLY MORNING. KEPT OVERNIGHT LOWS IN THE LOWER 70S...PER
PERSISTENCE.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A WEAK LOW WILL FORM IN THE MID ATLANTIC AREA ON SATURDAY...ALONG
THE REMAINS OF THE FRONT AND PUSH SOUTHWARD INTO THE FORECAST
AREA SATURDAY NIGHT. CYCLONIC FLOW WILL CONTINUE ALOFT...ALLOWING
SHORT WAVE TO MOVE ACROSS THE COAST STATES. WITH MAX TEMPERATURES
CONTINUING IN THE MID TO UPPER 90S...HIGH INSTABILITY AND PWAT
VALUES RISING TO 1.8 TO 1.9 INCHES THE POTENTIAL FOR STRONG TO
SEVERE THUNDERSTORMS WILL CONTINUE. LARGE HAIL THREAT WILL BE LOW
AS FREEZING AND WET BULB ZERO LEVELS WILL BE ABOVE 14 KFT AND 12
KFT RESPECTIVELY. OVERNIGHT LOWS WILL BE IN THE LOWER 70S.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM WITH SOME
MINOR DIFFERENCES IN TIMING AND INTENSITY. WEAK LOW PRESSURE WILL
SLIDE OFFSHORE OF THE MID ATLANTIC STATES ON SUNDAY WITH THE
REMAINS OF THE FRONT PUSHING THROUGH THE FORECAST AREA ON SUNDAY
THEN STALLING JUST SOUTH OF THE AREA SUNDAY NIGHT THROUGH EARLY
TUESDAY. THE FRONT WILL MEANDER NORTHWARD ON TUESDAY AS THE NEXT
LOW PRESSURE SYSTEM CROSSES THE GREAT LAKES. AS THE LOW TRACKS
FURTHER EASTWARD WEDNESDAY AND THURSDAY THE COLD FRONT WILL CROSS
INTO THE EASTERN US THEN STALL ACROSS THE AREA. THIS SERIES OF
FEATURES WILL KEEP CHANCES OF SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH THE LONG TERM. TEMPERATURES THROUGH THE LONG TERM
WILL BE NEAR TO SLIGHTLY ABOVE NORMAL WITH DAYTIME HIGHS IN THE
LOWER TO MIDDLE 90S AND OVERNIGHT LOWS IN THE LOWER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
GENERALLY VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE
PERIOD.
SKIES PARTLY CLOUDY WITH BASES AROUND 5KFT THROUGH THE AFTERNOON.
WINDS WILL GENERALLY REMAIN LIGHT AND SOMEWHAT VARIABLE. STRONG
SURFACE HEATING COMBINED WITH A SHORTWAVE MOVING OUT OF THE
CENTRAL APPALACHIANS WILL PROVIDE A FOCUS FOR SOME AFTERNOON
CONVECTION. CONVECTION SHOULD BE SCATTERED. DUE TO UNCERTAINTY IN
TIMING...DEVELOPMENT...AND EVENTUAL MOVEMENT OF STORMS...WILL NOT
INCLUDE IN THE FORECAST AT THIS TIME. UPDATES WILL BE REQUIRED IF
CONVECTION IS ABLE TO APPROACH TERMINALS LATE IN THE AFTERNOON. DEBRIS
CLOUDS THIS EVENING COULD INHIBIT FOG DEVELOPMENT SATURDAY MORNING.
EXTENDED AVIATION OUTLOOK...EARLY MORNING MVFR/IFR FOG POSSIBLE
EACH DAY...MAINLY AT FOG PRONE SITES AGS/OGB. SCATTERED DIURNAL
THUNDERSTORMS EXPECTED EACH AFTERNOON AND EVENING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1127 AM EDT FRI JUN 20 2014
.SYNOPSIS...
A SURFACE TROUGH WILL REMAIN ACROSS THE AREA THROUGH SUNDAY AS
UPPER LEVEL RIDGING SLIDES WESTWARD. ABOVE NORMAL TEMPERATURES
AND THE CHANCE FOR THUNDERSTORMS WILL CONTINUE INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...THE AIRMASS WILL BECOME MODERATELY UNSTABLE
WITH LIFTED INDEX FORECAST TO BE -4C TO -6C AND CONTINUED WEAK
WIND SHEAR. LINGERING OUTFLOW BOUNDARIES FROM YESTERDAY MAY HELP
TO FOCUS CONVECTION THIS AFTERNOON. POSSIBLE WEAK SHORTWAVE ENERGY
MOVING OUT OF THE MOUNTAINS COULD AID IN CONVECTIVE DEVELOPMENT
IN THE NORTHERN HALF OF THE FORECAST AREA. PWAT VALUES WILL BE
AROUND 1.7 INCHES. MAX TEMPS IN THE MID-UPPER 90S WITH 20+
DEWPOINT DEPRESSIONS...SO ANY STORMS THAT DEVELOP COULD BECOME
SEVERE WITH A DAMAGING WIND THREAT. HAIL LOOKS TO BE LESS OF A
THREAT WITH FREEZING LEVEL AROUND 14.2 KFT AND 500MB TEMP AROUND
-8C. LOCAL MODEL ALONG WITH THE HRRR SHOWS SCATTERED CONVECTION
DEVELOPING LATE IN THE AFTERNOON...LASTING WELL INTO THE EVENING.
WILL GO WITH 20 TO 40 PERCENT POPS FOR THE LATE AFTERNOON AND
EVENING.
TONIGHT...CONVECTION WILL DIMINISH BY MIDNIGHT. HOWEVER...THE
AIRMASS WILL REMAIN UNSTABLE WITH PERHAPS A WEAK SHORT
WAVE. EVEN THOUGH CANNOT TOTALLY RULE OUT A SHOWER OR THUNDERSTORM
OVERNIGHT...ELECTED TO GO WITH MAINLY DRY FORECAST LATE TONIGHT
THROUGH EARLY MORNING. KEPT OVERNIGHT LOWS IN THE LOWER 70S...PER
PERSISTENCE.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A WEAK LOW WILL FORM IN THE MID ATLANTIC AREA ON SATURDAY...ALONG
THE REMAINS OF THE FRONT AND PUSH SOUTHWARD INTO THE FORECAST
AREA SATURDAY NIGHT. CYCLONIC FLOW WILL CONTINUE ALOFT...ALLOWING
SHORT WAVE TO MOVE ACROSS THE COAST STATES. WITH MAX TEMPERATURES
CONTINUING IN THE MID TO UPPER 90S...HIGH INSTABILITY AND PWAT
VALUES RISING TO 1.8 TO 1.9 INCHES THE POTENTIAL FOR STRONG TO
SEVERE THUNDERSTORMS WILL CONTINUE. LARGE HAIL THREAT WILL BE LOW
AS FREEZING AND WET BULB ZERO LEVELS WILL BE ABOVE 14 KFT AND 12
KFT RESPECTIVELY. OVERNIGHT LOWS WILL BE IN THE LOWER 70S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM WITH SOME
MINOR DIFFERENCES IN TIMING AND INTENSITY. WEAK LOW PRESSURE WILL
SLIDE OFFSHORE OF THE MID ATLANTIC STATES ON SUNDAY WITH THE
REMAINS OF THE FRONT PUSHING THROUGH THE FORECAST AREA ON SUNDAY
THEN STALLING JUST SOUTH OF THE AREA SUNDAY NIGHT THROUGH EARLY
TUESDAY. THE FRONT WILL MEANDER NORTHWARD ON TUESDAY AS THE NEXT
LOW PRESSURE SYSTEM CROSSES THE GREAT LAKES. AS THE LOW TRACKS
FURTHER EASTWARD WEDNESDAY AND THURSDAY THE COLD FRONT WILL CROSS
INTO THE EASTERN US THEN STALL ACROSS THE AREA. THIS SERIES OF
FEATURES WILL KEEP CHANCES OF SHOWERS AND THUNDERSTORMS IN THE
FORECAST THROUGH THE LONG TERM. TEMPERATURES THROUGH THE LONG TERM
WILL BE NEAR TO SLIGHTLY ABOVE NORMAL WITH DAYTIME HIGHS IN THE
LOWER TO MIDDLE 90S AND OVERNIGHT LOWS IN THE LOWER 70S.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
GENERALLY VFR CONDITIONS EXPECTED THROUGH THE MAJORITY OF THE
PERIOD.
MOSTLY SUNNY SKIES WILL GIVE WAY TO AFTERNOON CUMULUS CLOUDS.
WINDS WILL GENERALLY REMAIN LIGHT FROM THE WEST TO NORTHWEST LATE
MORNING AROUND 5 TO 8 MPH. A THERMAL TROUGH WILL DEVELOP FROM
STRONG SURFACE HEATING AND COULD PROVIDE A FOCUS FOR SOME
AFTERNOON CONVECTION. CONVECTION SHOULD BE ISOLATED TO SCATTERED
AND WILL NOT INCLUDE IN THE FORECAST AT THIS TIME. AFTERNOON
CONVECTION MAY RESULT IN DEBRIS CLOUDS THIS EVENING WHICH COULD
INHIBIT FOG DEVELOPMENT SATURDAY MORNING.
EXTENDED AVIATION OUTLOOK...EARLY MORNING MVFR/IFR FOG POSSIBLE
EACH DAY...MAINLY AT FOG PRONE SITES AGS/OGB. SCATTERED DIURNAL
THUNDERSTORMS EXPECTED EACH AFTERNOON AND EVENING.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
916 PM CDT SAT JUN 21 2014
.UPDATE...
ISSUED AT 916 PM CDT SAT JUN 21 2014
LITTLE CHANGE FROM PREVIOUS THINKING THIS EVENING. LARGE SCALE
FORCING AHEAD OF APPROACHING CO/WY SHORT WAVES WILL KEEP SCATTERED
CONVECTION GOING IN SOME FORM UPSTREAM OVERNIGHT. SD MCS IS MOST
PRESSING CONCERN BUT SEVERE WEATHER POTENTIAL SEEMS LOW. ALTHOUGH
A FEW CELLS HAVE ACCELERATED FASTER FOR THE MOMENT...COMPLEX IS
CURRENTLY FOLLOWING CORFIDI VECTORS AS A WHOLE AND DRIFTING SE AT
15-20KTS. EXPECT THIS COMPLEX TO WEAKEN SOMEWHAT WITH
DECREASE/INCREASE IN MLCAPE/CINH RESPECTIVELY INTO THE NIGHT AND
JUST WEAK TO MODERATE EFFECTIVE SHEAR. HEAVY RAIN IS MORE OF A
CONCERN THAN SEVERE WITH ELEVATED K INDEX/PW AXIS DRIFTING EWD
INTO WRN IA COINCIDENT WITH LOW LEVEL MOISTURE FLUX AS IT MOVES
EWD WITH OVERALL SYSTEM AND VEERS. 01Z RAP CORFIDI VECTORS/MEAN
WIND ARE BOTH 15KTS OR LESS BY 09Z SO WHAT IS LEFT OF THE COMPLEX
WILL LIKELY BE SLOW MOVING. AIRMASS WILL SUPPORT EFFICIENT
RAINFALL RATES BUT PWS AND WARM CLOUD DEPTHS ARE NOT AS EXTREME AS
RECENT EVENTS.
&&
.SHORT TERM /TONIGHT/...
ISSUED AT 320 PM CDT SAT JUN 21 2014
CONVECTIVE TRENDS OVERNIGHT ARE THE PRIMARY FORECAST CHALLENGE
OVERNIGHT. MCV SHIFTING EAST ACROSS SRN WISCONSIN AND NRN ILLINOIS
HAS WRAPPED DRY MID LEVEL AIR IN TO CENTRAL AND EASTERN IOWA. THIS
HAS HELPED STRENGTHEN THE CONVECTIVE INHIBITION ACROSS THE AREA.
SFC FLOW OVER CENTRAL IOWA REMAINS NEARLY NON EXISTENT WITH THE
OVERNIGHT OUTFLOW PUSHING THE WARM FRONT JUST SOUTH INTO KANSAS
AND MISSOURI. A FEW STORMS HAVE BEEN TRYING TO INITIATE ALONG THIS
BOUNDARY BUT HAVING A DIFFICULT TIME BECOMING ORGANIZED WITH A
LACK OF DEEP LAYER SHEAR AND ANY GOOD FORCING TO AID IN SUSTAINING
UPDRAFTS. THIS ACTIVITY SHOULD MOSTLY REMAIN SOUTH OF THE STATE
BUT MAY CLIP THE SOUTHERN TIER OF COUNTIES THE NEXT FEW HOURS.
FORCING REMAINS WEAK ACROSS CENTRAL IOWA THROUGH THIS EVENING. THE
LOW LEVEL JET OF AROUND 35 KTS WILL AMPLIFY OVER THE MID MISSOURI
VALLEY AND POINTS TO THE WEST HOWEVER ITS ORIENTATION WILL FAVOR
THE FORCING AND CONVERGENCE ZONE ACROSS NEBRASKA AND SOUTH DAKOTA.
A SHORT WAVE MOVING RAPIDLY ACROSS THE ROCKIES OVERNIGHT SHOULD
SPREAD QG FORCING EAST INTO WESTERN IOWA LATE AND WILL HAVE PUSH
ANY DEVELOPING MCS CLOSE TO THE STATE LATE. POSSIBLE A FEW STORMS
DEVELOP OVER THE CENTRAL AND SOUTHWEST AS A COUPLE WAVES OF
THETA-E ADVECTION LIFT NORTH AND GENERATE AN INSTABILITY AXIS
THROUGH THAT REGION. A DISCONTINUITY BETWEEN FORCING AND MOISTURE
AVAILABLE SHOULD PREVENT WIDESPREAD ACTIVITY AHEAD OF THE WESTERN
MCS. THE THREAT FOR SEVERE WEATHER IS LOW THROUGH THE PERIOD
THOUGH CAN NOT DISCOUNT A LOCALIZED EVENT. THE THREAT FOR HEAVY
RAIN IS ALSO LOW THROUGH 12Z.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
ISSUED AT 320 PM CDT SAT JUN 21 2014
MAIN CONCERNS CONTINUE TO FOCUS ON POTENTIAL FOR HEAVY RAINFALL WITH
NEXT UPSTREAM WAVE EXPECTED TO CROSS THE REGION SUNDAY INTO EARLY
MONDAY. EXPECTING SOME LEFTOVER CONVECTION ONCE AGAIN EARLY SUNDAY
MORNING TO DECAY DURING THE MORNING HOURS ACROSS THE NORTH. A
SLIGHTLY WEAKER WAVE IS NOW EXPECTED CROSS THE REGION INTO MONDAY.
PREVIOUS MODEL SOLUTIONS SUGGESTED A STRONGER WAVE TRACKING OVER
SOUTHERN IOWA/NORTHERN MISSOURI BUT LAST 2 RUNS OF THE MODELS SHOW
SOMEWHAT OF A SPLIT NORTHERN/SOUTHERN STREAM WAVE CROSSING THE
REGION. THIS SHOULD RESULT IN A LESSER THREAT FOR WIDESPREAD HEAVY
RAIN ACROSS THE SOUTHEAST TWO THIRDS OF THE AREA FOR SUNDAY
THROUGH MONDAY...BUT INCREASE THE RISK OF RAINFALL AND SOME
LOCALLY HEAVY RAIN OVER THE NORTHERN AREAS OF THE FORECAST AREA.
BOTH THE 12Z GFS/NAM ARE NOW FAVORING THE NORTHERN STREAM ENERGY
TO DOMINATE THE NEXT 24 TO 36 HOURS...WITH WARM AIR ADVECTION AND
FRONTAL FORCING MAXIMIZED FROM NORTHWEST IOWA THROUGH SOUTHEAST
MINNESOTA AND A SECONDARY WAVE WELL SOUTH OF THE AREA. THIS LEAVES
THE BULK OF CENTRAL IOWA IN AN AREA OF LESS FAVORABLE CONVERGENCE
AND FORCING. TODAYS 12Z GEM MODEL HAS ALSO SPLIT THE ENERGY IN A
SIMILAR PATTERN...WITH SYNOPTIC DEVELOPMENT OF THE WAVES OVER
NORTHERN IOWA AND IN THE SOUTHERN PLAINS. THIS WOULD FAVOR TWO
AREAS OF HEAVIER RAINFALL...ONE OVER NORTHERN IOWA AND THE OTHER
OVER MISSOURI SOUTH TO NEAR THE OKLAHOMA/ARKANSAS BORDER. WITH THE
SUGGESTION OF SPLIT FLOW...THE PATTERN WOULD BE MORE PROGRESSIVE
WITH A QUICKER EXIT OF THE FRONT BY LATE MONDAY MORNING RATHER
THAN MONDAY NIGHT. OVERALL THIS SHOULD HELP LIMIT WIDESPREAD HEAVY
RAINFALL. HOWEVER...WE CONTINUE HAVE HIGH PRECIPITABLE WATER
VALUES OF 1.5 TO 1.75 WITH WARM CLOUD DEPTHS ONCE AGAIN RUNNING
FROM 11500 TO 13000 FT. THERE MAY STILL BE LOCALLY HEAVY RAINFALL
NEARER THE SFC LOW AS IT TRACKS ACROSS CENTRAL TO NORTHERN IOWA
WITH MORE WIDELY SCATTERED POCKETS OF LOCALLY HEAVY RAINFALL IN
THE CENTRAL AND SOUTH MAINLY DURING THE AFTERNOON AND EVENING
HOURS. HIGHS SUNDAY WILL BE VERY WARM...BUT WITH CLOUD COVER
AROUND PROBABLY HELD INTO THE LOWER TO MID 80S WITH A FEW UPPER
80S IN THE SOUTH. COOLER WEATHER WILL RETURN TOWARD MONDAY AND
TUESDAY AS THE SYSTEM PULLS EAST. TUESDAY MORNING EITHER LOOKS TO
BE A GREAT CANDIDATE FOR FOG OR A LOT OF DEW. WILL NEED TO TAKE A
LOOK AT THIS IN THE NEXT PACKAGE OR TWO AS WINDS BECOME VERY LIGHT
BY THAT TIME AND TEMPERATURES RADIATE BACK INTO THE LOWER 60S.
THERE REMAINS A WEAK SIGNAL FOR SOME SHOWERS TUESDAY OR WEDNESDAY
OVER THE NORTH AND WEDNESDAY OVER THE CENTRAL. FOR NOW...GREATER
UNCERTAINTY ABOUT CHANCES FOR RETURN MOISTURE THAT SOON...AND THIS
MAY CHANGE. BY MID TO LATE IN THE PERIOD A WEST SOUTHWEST FLOW
WILL RETURN ALOFT. THIS WILL PROMOTE WARMER TEMPERATURES AND
INCREASED CHANCES FOR THUNDERSTORMS. HIGHS THROUGH MIDWEEK WILL
REMAIN IN THE LOWER 80S WITH LOWS IN THE 60S. BY LATE IN THE
PERIOD MID 80S ARE MORE LIKELY WITH LOWS IN THE UPPER 60S TO LOWER
70S. AS TEMPS WARM ALOFT AT H700 TO ABOVE 10C...THUNDERSTORM
CHANCES MAY BE CAPPED BUT UNCERTAINTY INCREASES TOWARD THE END OF
THE EXTENDED FORECAST.
&&
.AVIATION...22/00Z
ISSUED AT 652 PM CDT SAT JUN 21 2014
VFR CONDITIONS ARE ANTICIPATED THROUGH THE EVENING WITH THE
ATTENTION TURNING UPSTREAM OVERNIGHT AND INTO SUN FOR CONVECTIVE
TRENDS. SHOWERS AND STORMS ARE POSSIBLE EARLY IN THE DAY AS
LARGER SCALE FORCING CROSSES THE PLAINS...WITH SURFACE BASED
CONVECTION ALSO POSSIBLE WEST LATER IN THE DAY. HAVE FAIRLY HIGH
CONFIDENCE IN CONVECTION SOMETIME SUN...BUT TIMING AND LOCATIONS
HAVE LITTLE PREDICTABILITY AT THIS POINT SO HAVE NOTHING MORE
THAN PROLONGED VFR VCSH WORDING FOR NOW.
&&
.HYDROLOGY...
ISSUED AT 320 PM CDT SAT JUN 21 2014
...TONIGHT THROUGH MONDAY NIGHT...
THE MAIN CONCERN LATE TONIGHT AND EARLY SUNDAY WILL BE MCS
DEVELOPMENT OVER THE WESTERN PLAINS...MOVING EAST INTO NORTHWEST
IOWA BY MORNING. THIS ACTIVITY SHOULD DECAY EARLY IN THE DAY BUT
AS THE MAIN SHORTWAVE MOVES ACROSS THE AREA SUNDAY...THUNDERSTORMS
WILL INCREASE IN COVERAGE. WITH PWATS CONTINUING HIGH AND WARM
CLOUD DEPTHS FAVORING EFFICIENT RAINFALL PROCESSES...SOME AMOUNTS
OF 1 TO 2 INCHES IN A SHORT PERIOD OF TIME WILL BE POSSIBLE SUNDAY
INTO SUNDAY EVENING ESPECIALLY. MOST 1 AND 3 HOUR GRIDDED FLASH
FLOOD GUIDANCE OVER THE REGION IS ABOUT 1 TO 2 INCHES...SO IF ANY
STORMS WITH HIGH RAINFALL RATES DEVELOP...THERE WILL BE A
POTENTIAL FOR SOME LOCALIZED FLOODING ISSUES. ONE LIMITING FACTOR
SUNDAY WILL BE A SLIGHTLY MORE PROGRESSIVE WAVE AS THE MAIN
SHORTWAVE TRACKS EAST. CONFIDENCE OF OVERALL COVERAGE AND LOCATION
IS LOW ENOUGH TO LEAVE HEADLINES OUT FOR NOW. RIVER LEVELS WILL
RESPOND AGAIN TO ANY ADDITIONAL RAINFALL OVER OUR FORECAST AREA
SUNDAY AND SUNDAY EVENING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...DONAVON
LONG TERM...REV
AVIATION...SMALL
HYDROLOGY...REV
AREA FORECAST DISCUSSION
NWS TOPEKA KS
635 PM CDT Sat Jun 21 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Sunday)
Issued at 315 PM CDT SAT JUN 21 2014
19Z water vapor imagery continues to shows a quasi-zonal flow across
the central Rockies and into the plains. There may be one or two
Mesoscale Convective Vortices (MCV) moving along the KS/NEB state
line with the more obvious one crossing the MO river and headed into
central MO. There also appears to be a subtle shortwave moving
through ID and northern UT. At the surface, a trough of low pressure
extended from the Dakotas south through eastern CO. Surface OBS show
the better low level moisture has shifted a little to the east with
much of the 70 degree dewpoints.
Late this afternoon and this evening is anticipated to be mostly dry
with general subsidence from the MCV over eastern KS and the deeper
moisture to the east of the area. This combined with a lack of
organized low level convergence should favor any isolated storms
remaining east of the forecast area. Will have to watch and see if
any of the convection off the higher terrain holds together long
enough to reach north central KS. There are some indications from
the RAP and HRRR that there could be some precip move into Republic
and Cloud counties around midnight. However those solutions seem to
be a little to aggressive in developing convection earlier in the
day, so I don`t know how much weight to give these solutions. Will
have some small POPs after midnight for far northern counties in
case some shower and thunderstorm activity is able to hang together.
Lows tonight should once again be mild with readings around 70 due to
southerly winds and warm air remaining over the area.
For Sunday, the subtle shortwave out west is progged to be moving
out into the plains, mainly to the north of the forecast area.
However the synoptic scale surface trough is expected to be a little
further east into KS. Convergence along this boundary coupled with
some weak forcing from the upper wave could cause a broken line of
storms to form by the afternoon hours. Instability is expected to be
high once again with good low level moisture still in place. However
due to weak mid level flow, deep layer shear is progged to only be
from 15 to 25 kts. This would favor multi cell clusters with a hail
and strong wind hazard. North central KS looks like the most likely
place for this storms to form during the afternoon. Temps for Sunday
are expected to be similar to today`s or maybe a degree or two
cooler. Models show a slight cooling trend at 850 and there could be
higher clouds increasing by the afternoon from the potential
convection to the west. Because of this have highs generally in the
lower 90s.
.LONG TERM...(Sunday Night through Saturday)
Issued at 315 PM CDT SAT JUN 21 2014
Overall trend is for the upper wave to be less intense as it passes
through Sunday night into early Monday. Still looks like a good
opportunity for for most locations to receive at least one round of
precip with the slow moving system weak front moving through a moist
early-summer airmass and limited inhibition. Severe weather concerns
should diminish with time in the evening hours with a least some
chance for pockets of heavier precipitation, though setup does not
point to any particularly area at this point. Monday should slowly dry
with the departing wave with Monday night and much of Tuesday still
looking to be the more likely dry periods of this forecast.
Models do show some similarities with a weak wave passing mainly
south of the area late Tuesday into Wednesday, but moisture does
return north with this wave with modest flow keeping mid levels from
warming too fast for at least small thunderstorm chances. Upper flow
amplifies over the western and eventually central CONUS into the end
of the forecast. Expect capping to increase enough for a mainly dry
end to the work week with chances picking up again by Saturday as
forcing increases. Temps should slowly warm through the latter
portions of the week, with 90s possible by Saturday.
&&
.AVIATION...(For the 00Z TAFs through 00Z Sunday Evening)
Issued at 632 PM CDT SAT JUN 21 2014
VFR conditions through most of the taf period. A boundary will
approach central KS later tomorrow and daytime heating could lead
to afternoon thunderstorms. Confidence is low at this point and
timing appears to be late in the period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
601 PM CDT Sat Jun 21 2014
...updated aviation section...
.SHORT TERM...(This evening through Sunday)
ISSUED AT 120 PM CDT SAT JUN 21 2014
Short range models indicate an upper level shortwave pushing across
the Colorado Rockies into the Western High Plains tonight creating
thunderstorm chances lee of the Rockies through early Sunday. As
the shortwave approaches, moisture will continue to advect northward
into central and much of western Kansas ahead of a developing
surface low in extreme eastern Colorado. Although the flow aloft
will remain fairly weak, plenty of instability combined with
increased low level convergence in the vicinity of the surface
trough will be enough to support thunderstorm development lee of
the Rockies late this afternoon. A few of these storms could drift
into west central and portions of southwest Kansas this evening
through the overnight hours. The upper level shortwave will move
further east across the high plains Sunday dislodging the surface
low/trough into western Kansas and shifting the focus for
thunderstorm development along with it. Although the flow aloft
will remain fairly weak, steep low/mid level lapse rates and
SBCAPE values in excess of 3000 J/KG ahead of the surface trough
will be enough to support strong to potentially lower threshold
severe storms. The potential for periods of heavy rainfall with
the strongest storms exist as well with NAM/GFS model soundings
indicating PW values well in excess of 1.5 inches. Localized
flooding could be an issue, especially going into Sunday evening.
As a low level southerly flow prevails across central and western
Kansas tonight, moisture advection into the region will help keep
surface dewpoints well up into the 50s(F) to the lower 60s(F)
tonight. Look for lows only down into the mid to upper 60s(F)
early Sunday morning with near 70F likely in portions of central
and south central Kansas. Little change to the air mass is expected
from today into Sunday, so highs can be expected back up into the
90s(F) once again Sunday afternoon.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 225 PM CDT SAT JUN 21 2014
Widespread convection will continue Sunday night as a cold front
moves across western Kansas. MCS development still appears
possible overnight based on improving low level frontogenesis and
mid level instability ahead of an upper level disturbance as it
crosses the Central High Plains. Given the high preciptable water
values along the low level thta-e axis the main hazard overnight
will veer away from large hail and strong winds early and become
more of a heavy rainfall event.
The steady rainfall will taper off early Monday as the cold front
moves into Oklahoma and the Texas panhandle. Given the decreasing
clouds and 850mb temperature trends from 00z Monday to 00z Tuesday
will keep highs mainly in the mid 80s Monday afternoon.
ECMWF and GFS may differ on timing and track, however both agree
that several upper level disturbances will cross the Central
Plains from Monday night through at early Thursday. A low level
moisture axis will be in place across portions of eastern Colorado
and western Kansas as each of these disturbance passes which
continues to support daily precipitation chances. Monday and
Tuesday the better opportunity for precipitation appears be near
the Colorado border and across southwest Kansas given where the
location of low level moisture axis, afternoon instability, and
lift will be located by the GFS and ECMWF. The surface boundary
will then lift north as a warm front towards Nebraska mid week and
the 850mb and 700mb temperatures will begin to warm. Based on the
warming the GFS and ECMWF has in the 850mb to 700mb level late
week the latest CRExtendFcst_Init looks on track so will not stray
far. Precipitation chances mid to late week are expected to shift
from southwest Kansas into north central Kansas as the better lift
north of the warm front moves into northern Kansas and mid levels
warm across southwest Kansas.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 600 PM CDT SAT JUN 21 2014
Scattered thunderstorms over extreme west central Kansas are forecast
by the HRRR and other convective allowing models to diminish in
intensity before reaching the highway 83 corridor by mid evening.
Southerly winds will continue overnight, with diminishing gusts
around sunset. A frontal boundary will be the focus for thunderstorm
development again by mid afternoon Sunday, which will have a good
chance of affecting he local terminals in the late afternoon with
heavy rains and gusty winds.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 93 64 84 / 10 60 90 20
GCK 68 94 63 83 / 20 70 80 20
EHA 67 95 61 85 / 40 60 70 20
LBL 68 94 64 85 / 10 60 70 20
HYS 68 90 63 83 / 20 60 80 20
P28 70 93 69 87 / 10 50 90 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...JJohnson
LONG TERM...Burgert
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
918 PM EDT Sat Jun 21 2014
...Forecast Update...
Issued at 917 PM EDT Sat Jun 21 2014
Ran another update this evening mainly to bring grids up to speed
with current observations. As expected, convection is rapidly
weakening off to the northwest as the precipitation encounters a
much drier and more stable airmass. Therefore, will continue to
leave the forecast dry overnight. Also went ahead and added some
patchy fog to the grids across the Lake Cumberland region where the
heaviest rainfall fell this afternoon/evening. Otherwise, the rest
of the forecast looks on track.
Issued at 614 PM EDT Sat Jun 21 2014
Quick update this evening to account for ongoing trends. Despite a
few very isolated light showers, precipitation has ended across
southern KY. Therefore, will remove precip mention from the
forecast for the remainder of the evening hours. Attention will
then turn to the northwest as a line of showers and thunderstorms
continues to develop across IL/MO. The main forecast challenge
tonight will be just how far east that convection makes it. Given
it will be fighting much drier air that has protruded into southern
IN and into southern IL, think this convection will likely struggle
as it pushes east. However, the latest HRRR which has a good handle
on the current convection, does bring a weakening line into southern
IN around 06Z overnight. Given the drier air firmly in place, will
continue with a dry forecast but will continue to monitor trends
over the next few hours.
.SHORT TERM (Now through Sunday Night)...
Issued at 300 PM EDT Sat Jun 21 2014
The upper air pattern shows a progressive relatively flat flow at
500mb confined generally to the northern tier of states. Weak
northwest flow currently over the northern Ohio Valley will become
weaker as ridging is forecast to develop across the Lower
Mississippi Valley by late Sunday, extending northeastwards through
southern Indiana.
Expect only a few flat cumulus this afternoon along and north of
Interstate 64 as the shortwave that brought scattered thunderstorms
earlier this morning to the Lake Cumberland Region moves farther
southeast. Any additional isolated thunderstorms through late
afternoon will stay along and southeast of the Cumberland Parkway.
Expect mostly clear skies tonight with humid conditions and light
winds. Some patchy fog may once again develop across southern
Indiana and the Bluegrass Region, although not to the extent of
earlier this morning. Lows tonight will range from the mid 60s
across the Bluegrass and southern Indiana to near 70 elsewhere.
Despite adequate moisture and quite unstable conditions developing
Sunday afternoon, ridging aloft will inhibit any widespread
convection. Think that scattered thunderstorms may develop farther
north across Illinois and Indiana, with isolated storms at best
along and north of the Ohio River. Expect south central Kentucky to
stay dry. Highs Sunday will range from the upper 80s northeast to
the lower 90s southwest. Light south winds will develop Sunday
afternoon.
.LONG TERM (Monday through Saturday)...
Issued at 255 PM EDT Sat Jun 21 2014
Fairly typical summertime conditions expected for most of the
upcoming week, with a low-amplitude and somewhat progressive pattern
aloft.
Shortwave ridging on Monday will most likely allow for the warmest
temps of the week. However, the pattern is still just flat enough
and heights not getting into legitimate heat wave territory, so
expect temps to reach the lower 90s in most spots. This stays in
line with the more consistent and slightly cooler NAM MOS. Chance
POPs will re-enter the picture Monday afternoon as the ridging
begins to gradually weaken.
Best chance for showers and storms will be Tuesday into Tuesday
night, with the passage of an upper shortwave trof. High PWATs will
support a heavy rain and pulse wind threat.
The rest of the week will not see any real pattern change, but just
warm and humid conditions with isolated/scattered storms each day,
mainly in the afternoons.
Pattern aloft starts to amplify toward the end of the week with a
ridge nosing up into the Upper Midwest. This bears watch for a
possible break in our daily convection and temps possibly punching
back into the 90s at some point next weekend.
&&
.AVIATION (00Z TAF Update)...
Issued at 658 PM EDT Sat Jun 21 2014
Skies will remain clear to partly cloudy overnight as an area of
weak high pressure remains in control of the sensible weather. With
this high nearby, winds will go light and variable tonight. These
light winds coupled with mainly clear skies, could yield some light
MVFR fog at KBWG and/or KLEX. Given the ground had all day to dry
out today, along with low-level drier air working in, do not expect
this fog to be as dense as we saw this morning, if any even develops
at all.
Sunday will be partly cloudy with generally light winds. There may
be a stray shower or storm that develops in the afternoon hours, but
coverage will be too low to warrant any mention in the TAFs at this
time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........KJD
Short Term.....JSD
Long Term......RAS
Aviation.......KJD
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
659 PM EDT Sat Jun 21 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 614 PM EDT Sat Jun 21 2014
Quick update this evening to account for ongoing trends. Despite a
few very isolated light showers, precipitation has ended across
southern KY. Therefore, will remove precip mention from the
forecast for the remainder of the evening hours. Attention will
then turn to the northwest as a line of showers and thunderstorms
continues to develop across IL/MO. The main forecast challenge
tonight will be just how far east that convection makes it. Given
it will be fighting much drier air that has protruded into southern
IN and into southern IL, think this convection will likely struggle
as it pushes east. However, the latest HRRR which has a good handle
on the current convection, does bring a weakening line into southern
IN around 06Z overnight. Given the drier air firmly in place, will
continue with a dry forecast but will continue to monitor trends
over the next few hours.
.SHORT TERM (Now through Sunday)...
Issued at 300 PM EDT Sat Jun 21 2014
The upper air pattern shows a progressive relatively flat flow at
500mb confined generally to the northern tier of states. Weak
northwest flow currently over the northern Ohio Valley will become
weaker as ridging is forecast to develop across the Lower
Mississippi Valley by late Sunday, extending northeastwards through
southern Indiana.
Expect only a few flat cumulus this afternoon along and north of
Interstate 64 as the shortwave that brought scattered thunderstorms
earlier this morning to the Lake Cumberland Region moves farther
southeast. Any additional isolated thunderstorms through late
afternoon will stay along and southeast of the Cumberland Parkway.
Expect mostly clear skies tonight with humid conditions and light
winds. Some patchy fog may once again develop across southern
Indiana and the Bluegrass Region, although not to the extent of
earlier this morning. Lows tonight will range from the mid 60s
across the Bluegrass and southern Indiana to near 70 elsewhere.
Despite adequate moisture and quite unstable conditions developing
Sunday afternoon, ridging aloft will inhibit any widespread
convection. Think that scattered thunderstorms may develop farther
north across Illinois and Indiana, with isolated storms at best
along and north of the Ohio River. Expect south central Kentucky to
stay dry. Highs Sunday will range from the upper 80s northeast to
the lower 90s southwest. Light south winds will develop Sunday
afternoon.
.LONG TERM (Sunday night through Friday)...
Issued at 255 PM EDT Sat Jun 21 2014
Fairly typical summertime conditions expected for most of the
upcoming week, with a low-amplitude and somewhat progressive pattern
aloft.
Shortwave ridging on Monday will most likely allow for the warmest
temps of the week. However, the pattern is still just flat enough
and heights not getting into legitimate heat wave territory, so
expect temps to reach the lower 90s in most spots. This stays in
line with the more consistent and slightly cooler NAM MOS. Chance
POPs will re-enter the picture Monday afternoon as the ridging
begins to gradually weaken.
Best chance for showers and storms will be Tuesday into Tuesday
night, with the passage of an upper shortwave trof. High PWATs will
support a heavy rain and pulse wind threat.
The rest of the week will not see any real pattern change, but just
warm and humid conditions with isolated/scattered storms each day,
mainly in the afternoons.
Pattern aloft starts to amplify toward the end of the week with a
ridge nosing up into the Upper Midwest. This bears watch for a
possible break in our daily convection and temps possibly punching
back into the 90s at some point next weekend.
&&
.AVIATION (00Z TAF Update)...
Issued at 658 PM EDT Sat Jun 21 2014
Skies will remain clear to partly cloudy overnight as an area of
weak high pressure remains in control of the sensible weather. With
this high nearby, winds will go light and variable tonight. These
light winds coupled with mainly clear skies, could yield some light
MVFR fog at KBWG and/or KLEX. Given the ground had all day to dry
out today, along with low-level drier air working in, do not expect
this fog to be as dense as we saw this morning, if any even develops
at all.
Sunday will be partly cloudy with generally light winds. There may
be a stray shower or storm that develops in the afternoon hours, but
coverage will be too low to warrant any mention in the TAFs at this
time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........KJD
Short Term.....JSD
Long Term......RAS
Aviation.......KJD
AREA FORECAST DISCUSSION
NWS JACKSON KY
148 PM EDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 1039 AM EDT FRI JUN 20 2014
ISOLATED SHOWERS AND A FEW RUMBLES OF THUNDER CONTINUE ACROSS EASTERN
KY. LIKE PREVIOUS FORECAST...EXPECT THINGS TO START FIRING UP TO MORE
SCATTERED COVERAGE DURING THE AFTERNOON HOURS AS WE START TO HEAT UP.
UPDATED THE SKY GRIDS FOR THE NEXT FEW HOURS TO BETTER MATCH THE CURRENT
CONDITIONS...WITH COVERAGE EXPECTED TO INCREASE THROUGHOUT THE
AFTERNOON. LEFT POPS AS IS...WITH ISOLATED TO SCATTERED CHANCES OVER
THE NEXT FEW HOURS. ALSO INCLUDED THE LATEST OBSERVATIONAL DATA IN
THE CURRENT FORECAST TO MAKE SURE THE TEMPS...DEW POINTS...AND WINDS
FORECASTS ARE REFLECTING THE CURRENT DATA.
UPDATE ISSUED AT 750 AM EDT FRI JUN 20 2014
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT RADAR AND SATELLITE
TRENDS. SOME SHOWERS AND THUNDERSTORMS HAVE ALREADY DEVELOPED THIS
MORNING...THOUGH THEY SHOULD INCREASE IN COVERAGE AND INTENSITY BY
EARLY IN THE AFTERNOON. THE THREAT FOR SHOWERS AND THUNDERSTORMS
SHOULD LINGER THROUGH THE ENTIRE DAY. OUTSIDE OF SHOWERS AND
THUNDERSTORMS WARM AND HUMID WEATHER IS ANTICIPATED.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 359 AM EDT FRI JUN 20 2014
THE REGION REMAINS IN THE WARM SECTOR SOUTH OF A FRONTAL ZONE
EXTENDING FROM THE CAROLINAS NORTHWEST TOWARD LOW PRESSURE OVER THE
NORTHERN PLAINS AND UPPER MS VALLEY REGION. THE OVERALL FLOW ACROSS
THE CONUS ATTM IS RATHER ZONAL IN NATURE WITH MID LEVEL RIDGING
CENTERED OVER THE LOWER MS RIVER VALLEY...WITH LOW AMPLITUDE RIDGING
NORTH TOWARD THE OH RIVER VALLEY. WELL TO THE NORTHEAST OF EAST KY...
A MID LEVEL LOW AND ASSOCIATED SFC LOW THAT HAS HELPED TO PUSH THE
BOUNDARY SOUTH ALONG THE EASTERN SEABOARD TO THE CAROLINAS REMAINS
PLACE WHILE A CLOSED LOW IS WORKING ACROSS THE NORTHERN ROCKIES
TOWARD THE NORTHERN PLAINS REGION ALONG US/CANADIAN BORDER.
MEANWHILE...A SHORTWAVE TROUGH IS SLOWLY WORKING FROM THE PLAINS INTO
THE MID MS AND LOWER OH VALLEY REGION.
THE SHORTWAVE TROUGH WILL WORK INTO THE LOWER OH VALLEY REGION OVER
THE NEXT FEW HOURS AND IS POISED TO MOVE ACROSS EASTERN KY AND INTO
THE APPALACHIAN REGION LATE THIS AFTERNOON AND INTO THIS EVENING. AS
THIS SHORTWAVE APPROACHES A SFC WAVE SHOULD DEVELOP AND WORK EAST
SOUTHEAST ALONG THIS NEARLY STATIONARY BOUNDARY AND CROSS THE
APPALACHIANS TONIGHT. THIS LOW SHOULD REACH THE EASTERN SEABOARD ON
SATURDAY WITH THE TAILING COLD FRONT GRADUALLY SAGGING INTO EASTERN
KY AND CROSSING MUCH OF THE AREA BY THE END OF THE PERIOD.
THROUGH SHORTLY AFTER DAWN...PATCHY RIVER VALLEY FOG SHOULD REMAIN IN
PLACE...WITH THIS FOG GRADUALLY BEGINNING TO LIFT AND POSSIBLY
AFFECTING A FEW RIDGETOP LOCATIONS NEAR LOCATIONS THAT EXPERIENCED
THE HEAVIER RAINFALL ON THU AND THU EVENING. THIS FOG SHOULD LIFT AND
DISSIPATE SHORTLY AFTER DAWN. ALSO...THE NEAR TERM MODELS SUCH AS
RECENT HRRR RUNS AND RECENT RAP RUNS HAVE SOME CONVECTION DEVELOPING
NEAR SUNRISE BETWEEN JKL AND LOZ OR FROM ESTILL COUNTY SOUTH TO BELL
COUNTY AND THEN MOVING EAST TO NEAR THE KY 15 CORRIDOR FROM JKL SOUTH
TO THE VA BORDER AND THEN INTO FAR SOUTHEAST KY BEFORE NOON. THE 6Z
NAM ALSO HAS SOME CONVECTION...BUT IS FURTHER EAST NEAR TO THE VA
BORDER ACROSS THE BIG SANDY REGION. HOWEVER...EVEN IF THERE IS SOME
MORNING CONVECTION...JUST A FEW HOURS OF THE STRONG JUNE SUNSHINE
SHOULD BRING MID TO UPPER 80S SFC TEMPS WITH SFC DEWPOINTS IN THE
MID 60S TO NEAR 70 DEGREE RANGE TO YIELD CAPE OF 2000 J/KG OR MORE BY
MID TO LATE AFTERNOON. LAPSE RATES IN THE MID LEVELS WILL NOT BE
PARTICULARLY STRONG AND RATHER WEAK SHEAR SHOULD LIMIT STORM
ORGANIZATION. HOWEVER... A FEW CELLS...POSSIBLY SECOND AND THIRD
GENERATION CELLS THAT DEVELOP NEAR OUTFLOW INTERSECTIONS COULD BECOME
STRONG TO LOCALLY SEVERE AND PRODUCE STRONG TO LOCALLY DAMAGING WIND
GUSTS. SPC HAS PLACED THE REGION IN A SEE TEXT AREA WITH 5 PERCENT
PROBABILITIES FOR SEVERE THUNDERSTORM CRITERIA WINDS AND THIS APPEARS
REASONABLE.
THE MAIN THREAT FROM STORMS LATER TODAY AND TONIGHT MAY END UP BEING
LOCALLY HEAVY RAINFALL RATES AS PW IS EXPECTED TO BE AT OR ABOVE THE
75TH PERCENTILE. THE PRESENCE OF THE SAGGING BOUNDARY AND THE
POTENTIAL FOR CONVECTION TO TRAIN IN SOME AREAS AS THE STEERING FLOW
MAY BECOME NEARLY PARALLEL TO THE SAGGING BOUNDARY OR OUTFLOWS COULD
LEAD TO A LOCALIZED THREAT OF FLOODING. UNCERTAINTY REMAINS IN THE
DETAILS AS FAR AS TIMING AND LOCATION. IN GENERAL...IT APPEARS THAT
AS THE SHORTWAVE WORKS INTO EASTERN KY AND THE APPALACHIANS...CONVECTION
SHOULD BE MOST WIDESPREAD DURING THE LATE AFTERNOON INTO LATE EVENING.
THE HWO HAS BEEN ADJUSTED ACCORDINGLY FOR ALL OF THESE THREATS.
THE THREAT OF SOME CONVECTION WILL LINGER EVEN INTO THE DAY ON
SATURDAY AND WILL PROBABLY FEATURE A DIURNAL UPTICK IN CONVERGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 406 AM EDT FRI JUN 20 2014
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH A TYPICAL
SUMMER PATTERN IN PLACE. A NEAR ZONAL UPPER LEVEL FLOW CONTINUES BUT
WITH THE USUAL MID LEVEL RIDGE IN THE SOUTHEAST NOW SHIFTED TOWARDS
THE WESTERN GULF OF MEXICO. BRIEF RIDGING WILL KEEP PRECIP MAINLY
DIURNALLY DRIVEN AS THE BULK OF THE SUPPORT EXITS EASTERN KENTUCKY
SATURDAY NIGHT...LEAVING ONLY SLIGHT CHANCE PRECIP INTO THE DAY ON
SUNDAY WITH THE MAX HEATING. BY MONDAY...A SIGNIFICANT SHORTWAVE
MOVES ACROSS THE PLAINS AND INTO THE OH VALLEY. THIS WAVE WILL BE THE
FOCUS OF ACTIVE WEATHER THROUGH THE MID PORTION OF THE EXTENDED.
THE MENTIONED WAVE PUSHES THROUGH ON MONDAY NIGHT AND TUESDAY
PUSHING A SURFACE COLD FRONT THROUGH. THIS FORCING AND THE WAVE
MOVING THROUGH WILL PROVIDE THE BEST CHANCE OF PRECIP ON TUESDAY AND
INTO TUESDAY NIGHT. THE EURO HINTS AT THE FRONT STALLING AND
BECOMING AN EAST WEST STATIONARY BOUNDARY ALONG SOUTHERN KY BY THE WED
AND THU TIME FRAME. THIS BECOMES AN POINT OF DEVELOPING CONVECTION
THROUGH THE LAST COUPLE DAYS OF THE EXTENDED. THE CHANCES WITH THIS
SET UP BECOME DIURNALLY DRIVEN WITH THE HEATING OF THE DAY. THE LACK
OF CONTINUITY OF GUIDANCE AND NEED TO STAY CONSISTENT WITH THE
NEIGHBORING OFFICES...LEAD TO KEEPING VALUES CLOSER TO THE ALL MODEL
BLEND SOLUTION. THE MONDAY THROUGH TUESDAY NIGHT PERIOD REMAINS A
PERIOD TO WATCH WITH THE STRONG WAVE MOVING THROUGH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 147 PM EDT FRI JUN 20 2014
SCATTERED TSRA HAVE STARTED TO DEVELOP ACROSS EASTERN KY...POSSIBLY
AFFECTING ANY OF THE TAF SITES THROUGH THE AFTERNOON AND EVENING.
THESE THUNDERSTORMS ARE MOVING QUICKLY...SO SHOULD NOT LAST VERY
LONG. HOWEVER...THEY COULD PRODUCE HEAVY RAIN...SMALL HAIL...FREQUENT
LIGHTNING...AND HIGH TO POSSIBLY DAMAGING WINDS. SINCE TSRA WILL BE
OFF AND ON...CHOSE TO USE A TEMPO GROUP WITH THE TSRA BEING THE NON
PREVAILING WX TYPE. TRIED TO GIVE THE BEST OVERALL GUESS FOR VSBY...BUT
EACH CELL WILL LIKELY BEHAVE DIFFERENTLY...WITH THE LEVEL OF RAINFALL
INFLUENCING THE VSBY RESTRICTION. EXPECT TSRA TO BE ON A
DIMINISHING TREND AT TAF SITES AFTER 4 OR 5Z...THOUGH ABUNDANT
MOISTURE AND LIGHT WINDS COULD LEAD TO SOME BR RESTRICTIONS
OVERNIGHT. DAYTIME HEATING IN THE MORNING WILL WORK TO BURN OFF ANY
BR...BUT WILL ALSO REINTRODUCE THE CHANCES FOR MORE SHOWERS AND
THUNDERSTORMS TO AFFECT TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...JP
LONG TERM...SHALLENBERGER
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
1043 AM EDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 1039 AM EDT FRI JUN 20 2014
ISOLATED SHOWERS AND A FEW RUMBLES OF THUNDER CONTINUE ACROSS EASTERN
KY. LIKE PREVIOUS FORECAST...EXPECT THINGS TO START FIRING UP TO MORE
SCATTERED COVERAGE DURING THE AFTERNOON HOURS AS WE START TO HEAT UP.
UPDATED THE SKY GRIDS FOR THE NEXT FEW HOURS TO BETTER MATCH THE CURRENT
CONDITIONS...WITH COVERAGE EXPECTED TO INCREASE THROUGHOUT THE
AFTERNOON. LEFT POPS AS IS...WITH ISOLATED TO SCATTERED CHANCES OVER
THE NEXT FEW HOURS. ALSO INCLUDED THE LATEST OBSERVATIONAL DATA IN
THE CURRENT FORECAST TO MAKE SURE THE TEMPS...DEW POINTS...AND WINDS
FORECASTS ARE REFLECTING THE CURRENT DATA.
UPDATE ISSUED AT 750 AM EDT FRI JUN 20 2014
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT RADAR AND SATELLITE
TRENDS. SOME SHOWERS AND THUNDERSTORMS HAVE ALREADY DEVELOPED THIS
MORNING...THOUGH THEY SHOULD INCREASE IN COVERAGE AND INTENSITY BY
EARLY IN THE AFTERNOON. THE THREAT FOR SHOWERS AND THUNDERSTORMS
SHOULD LINGER THROUGH THE ENTIRE DAY. OUTSIDE OF SHOWERS AND
THUNDERSTORMS WARM AND HUMID WEATHER IS ANTICIPATED.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 359 AM EDT FRI JUN 20 2014
THE REGION REMAINS IN THE WARM SECTOR SOUTH OF A FRONTAL ZONE
EXTENDING FROM THE CAROLINAS NORTHWEST TOWARD LOW PRESSURE OVER THE
NORTHERN PLAINS AND UPPER MS VALLEY REGION. THE OVERALL FLOW ACROSS
THE CONUS ATTM IS RATHER ZONAL IN NATURE WITH MID LEVEL RIDGING
CENTERED OVER THE LOWER MS RIVER VALLEY...WITH LOW AMPLITUDE RIDGING
NORTH TOWARD THE OH RIVER VALLEY. WELL TO THE NORTHEAST OF EAST KY...
A MID LEVEL LOW AND ASSOCIATED SFC LOW THAT HAS HELPED TO PUSH THE
BOUNDARY SOUTH ALONG THE EASTERN SEABOARD TO THE CAROLINAS REMAINS
PLACE WHILE A CLOSED LOW IS WORKING ACROSS THE NORTHERN ROCKIES
TOWARD THE NORTHERN PLAINS REGION ALONG US/CANADIAN BORDER.
MEANWHILE...A SHORTWAVE TROUGH IS SLOWLY WORKING FROM THE PLAINS INTO
THE MID MS AND LOWER OH VALLEY REGION.
THE SHORTWAVE TROUGH WILL WORK INTO THE LOWER OH VALLEY REGION OVER
THE NEXT FEW HOURS AND IS POISED TO MOVE ACROSS EASTERN KY AND INTO
THE APPALACHIAN REGION LATE THIS AFTERNOON AND INTO THIS EVENING. AS
THIS SHORTWAVE APPROACHES A SFC WAVE SHOULD DEVELOP AND WORK EAST
SOUTHEAST ALONG THIS NEARLY STATIONARY BOUNDARY AND CROSS THE
APPALACHIANS TONIGHT. THIS LOW SHOULD REACH THE EASTERN SEABOARD ON
SATURDAY WITH THE TAILING COLD FRONT GRADUALLY SAGGING INTO EASTERN
KY AND CROSSING MUCH OF THE AREA BY THE END OF THE PERIOD.
THROUGH SHORTLY AFTER DAWN...PATCHY RIVER VALLEY FOG SHOULD REMAIN IN
PLACE...WITH THIS FOG GRADUALLY BEGINNING TO LIFT AND POSSIBLY
AFFECTING A FEW RIDGETOP LOCATIONS NEAR LOCATIONS THAT EXPERIENCED
THE HEAVIER RAINFALL ON THU AND THU EVENING. THIS FOG SHOULD LIFT AND
DISSIPATE SHORTLY AFTER DAWN. ALSO...THE NEAR TERM MODELS SUCH AS
RECENT HRRR RUNS AND RECENT RAP RUNS HAVE SOME CONVECTION DEVELOPING
NEAR SUNRISE BETWEEN JKL AND LOZ OR FROM ESTILL COUNTY SOUTH TO BELL
COUNTY AND THEN MOVING EAST TO NEAR THE KY 15 CORRIDOR FROM JKL SOUTH
TO THE VA BORDER AND THEN INTO FAR SOUTHEAST KY BEFORE NOON. THE 6Z
NAM ALSO HAS SOME CONVECTION...BUT IS FURTHER EAST NEAR TO THE VA
BORDER ACROSS THE BIG SANDY REGION. HOWEVER...EVEN IF THERE IS SOME
MORNING CONVECTION...JUST A FEW HOURS OF THE STRONG JUNE SUNSHINE
SHOULD BRING MID TO UPPER 80S SFC TEMPS WITH SFC DEWPOINTS IN THE
MID 60S TO NEAR 70 DEGREE RANGE TO YIELD CAPE OF 2000 J/KG OR MORE BY
MID TO LATE AFTERNOON. LAPSE RATES IN THE MID LEVELS WILL NOT BE
PARTICULARLY STRONG AND RATHER WEAK SHEAR SHOULD LIMIT STORM
ORGANIZATION. HOWEVER... A FEW CELLS...POSSIBLY SECOND AND THIRD
GENERATION CELLS THAT DEVELOP NEAR OUTFLOW INTERSECTIONS COULD BECOME
STRONG TO LOCALLY SEVERE AND PRODUCE STRONG TO LOCALLY DAMAGING WIND
GUSTS. SPC HAS PLACED THE REGION IN A SEE TEXT AREA WITH 5 PERCENT
PROBABILITIES FOR SEVERE THUNDERSTORM CRITERIA WINDS AND THIS APPEARS
REASONABLE.
THE MAIN THREAT FROM STORMS LATER TODAY AND TONIGHT MAY END UP BEING
LOCALLY HEAVY RAINFALL RATES AS PW IS EXPECTED TO BE AT OR ABOVE THE
75TH PERCENTILE. THE PRESENCE OF THE SAGGING BOUNDARY AND THE
POTENTIAL FOR CONVECTION TO TRAIN IN SOME AREAS AS THE STEERING FLOW
MAY BECOME NEARLY PARALLEL TO THE SAGGING BOUNDARY OR OUTFLOWS COULD
LEAD TO A LOCALIZED THREAT OF FLOODING. UNCERTAINTY REMAINS IN THE
DETAILS AS FAR AS TIMING AND LOCATION. IN GENERAL...IT APPEARS THAT
AS THE SHORTWAVE WORKS INTO EASTERN KY AND THE APPALACHIANS...CONVECTION
SHOULD BE MOST WIDESPREAD DURING THE LATE AFTERNOON INTO LATE EVENING.
THE HWO HAS BEEN ADJUSTED ACCORDINGLY FOR ALL OF THESE THREATS.
THE THREAT OF SOME CONVECTION WILL LINGER EVEN INTO THE DAY ON
SATURDAY AND WILL PROBABLY FEATURE A DIURNAL UPTICK IN CONVERGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 406 AM EDT FRI JUN 20 2014
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH A TYPICAL
SUMMER PATTERN IN PLACE. A NEAR ZONAL UPPER LEVEL FLOW CONTINUES BUT
WITH THE USUAL MID LEVEL RIDGE IN THE SOUTHEAST NOW SHIFTED TOWARDS
THE WESTERN GULF OF MEXICO. BRIEF RIDGING WILL KEEP PRECIP MAINLY
DIURNALLY DRIVEN AS THE BULK OF THE SUPPORT EXITS EASTERN KENTUCKY
SATURDAY NIGHT...LEAVING ONLY SLIGHT CHANCE PRECIP INTO THE DAY ON
SUNDAY WITH THE MAX HEATING. BY MONDAY...A SIGNIFICANT SHORTWAVE
MOVES ACROSS THE PLAINS AND INTO THE OH VALLEY. THIS WAVE WILL BE THE
FOCUS OF ACTIVE WEATHER THROUGH THE MID PORTION OF THE EXTENDED.
THE MENTIONED WAVE PUSHES THROUGH ON MONDAY NIGHT AND TUESDAY
PUSHING A SURFACE COLD FRONT THROUGH. THIS FORCING AND THE WAVE
MOVING THROUGH WILL PROVIDE THE BEST CHANCE OF PRECIP ON TUESDAY AND
INTO TUESDAY NIGHT. THE EURO HINTS AT THE FRONT STALLING AND
BECOMING AN EAST WEST STATIONARY BOUNDARY ALONG SOUTHERN KY BY THE WED
AND THU TIME FRAME. THIS BECOMES AN POINT OF DEVELOPING CONVECTION
THROUGH THE LAST COUPLE DAYS OF THE EXTENDED. THE CHANCES WITH THIS
SET UP BECOME DIURNALLY DRIVEN WITH THE HEATING OF THE DAY. THE LACK
OF CONTINUITY OF GUIDANCE AND NEED TO STAY CONSISTENT WITH THE
NEIGHBORING OFFICES...LEAD TO KEEPING VALUES CLOSER TO THE ALL MODEL
BLEND SOLUTION. THE MONDAY THROUGH TUESDAY NIGHT PERIOD REMAINS A
PERIOD TO WATCH WITH THE STRONG WAVE MOVING THROUGH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 755 AM EDT FRI JUN 20 2014
ANY LINGERING VALLEY FOG SHOULD LIFT AND DISSIPATE BY 13Z. SOME
SHRA/TSRA CANNOT BE RULED OUT AT ANY POINT...BUT CHANCES APPEAR
GREATEST CLOSER TO WHEN AN UPPER LEVEL DISTURBANCE NEARS THE
REGION...GENERALLY AFTER 19Z OR 20Z THROUGH ABOUT 4Z. CONFIDENCE TIMING
IS UNCERTAIN...AND ONLY VCTS HAS BEEN USED IN TAFS AT THIS POINT.
SOME FOG MAY FORM LATE IN THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...JP
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
808 AM EDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 750 AM EDT FRI JUN 20 2014
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT RADAR AND SATELLITE
TRENDS. SOME SHOWERS AND THUNDERSTORMS HAVE ALREADY DEVELOPED THIS
MORNING...THOUGH THEY SHOULD INCREASE IN COVERAGE AND INTENSITY BY
EARLY IN THE AFTERNOON. THE THREAT FOR SHOWERS AND THUNDERSTORMS
SHOULD LINGER THROUGH THE ENTIRE DAY. OUTSIDE OF SHOWERS AND
THUNDERSTORMS WARM AND HUMID WEATHER IS ANTICIPATED.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 359 AM EDT FRI JUN 20 2014
THE REGION REMAINS IN THE WARM SECTOR SOUTH OF A FRONTAL ZONE
EXTENDING FROM THE CAROLINAS NORTHWEST TOWARD LOW PRESSURE OVER THE
NORTHERN PLAINS AND UPPER MS VALLEY REGION. THE OVERALL FLOW ACROSS
THE CONUS ATTM IS RATHER ZONAL IN NATURE WITH MID LEVEL RIDGING
CENTERED OVER THE LOWER MS RIVER VALLEY...WITH LOW AMPLITUDE RIDGING
NORTH TOWARD THE OH RIVER VALLEY. WELL TO THE NORTHEAST OF EAST KY...
A MID LEVEL LOW AND ASSOCIATED SFC LOW THAT HAS HELPED TO PUSH THE
BOUNDARY SOUTH ALONG THE EASTERN SEABOARD TO THE CAROLINAS REMAINS
PLACE WHILE A CLOSED LOW IS WORKING ACROSS THE NORTHERN ROCKIES
TOWARD THE NORTHERN PLAINS REGION ALONG US/CANADIAN BORDER.
MEANWHILE...A SHORTWAVE TROUGH IS SLOWLY WORKING FROM THE PLAINS INTO
THE MID MS AND LOWER OH VALLEY REGION.
THE SHORTWAVE TROUGH WILL WORK INTO THE LOWER OH VALLEY REGION OVER
THE NEXT FEW HOURS AND IS POISED TO MOVE ACROSS EASTERN KY AND INTO
THE APPALACHIAN REGION LATE THIS AFTERNOON AND INTO THIS EVENING. AS
THIS SHORTWAVE APPROACHES A SFC WAVE SHOULD DEVELOP AND WORK EAST
SOUTHEAST ALONG THIS NEARLY STATIONARY BOUNDARY AND CROSS THE
APPALACHIANS TONIGHT. THIS LOW SHOULD REACH THE EASTERN SEABOARD ON
SATURDAY WITH THE TAILING COLD FRONT GRADUALLY SAGGING INTO EASTERN
KY AND CROSSING MUCH OF THE AREA BY THE END OF THE PERIOD.
THROUGH SHORTLY AFTER DAWN...PATCHY RIVER VALLEY FOG SHOULD REMAIN IN
PLACE...WITH THIS FOG GRADUALLY BEGINNING TO LIFT AND POSSIBLY
AFFECTING A FEW RIDGETOP LOCATIONS NEAR LOCATIONS THAT EXPERIENCED
THE HEAVIER RAINFALL ON THU AND THU EVENING. THIS FOG SHOULD LIFT AND
DISSIPATE SHORTLY AFTER DAWN. ALSO...THE NEAR TERM MODELS SUCH AS
RECENT HRRR RUNS AND RECENT RAP RUNS HAVE SOME CONVECTION DEVELOPING
NEAR SUNRISE BETWEEN JKL AND LOZ OR FROM ESTILL COUNTY SOUTH TO BELL
COUNTY AND THEN MOVING EAST TO NEAR THE KY 15 CORRIDOR FROM JKL SOUTH
TO THE VA BORDER AND THEN INTO FAR SOUTHEAST KY BEFORE NOON. THE 6Z
NAM ALSO HAS SOME CONVECTION...BUT IS FURTHER EAST NEAR TO THE VA
BORDER ACROSS THE BIG SANDY REGION. HOWEVER...EVEN IF THERE IS SOME
MORNING CONVECTION...JUST A FEW HOURS OF THE STRONG JUNE SUNSHINE
SHOULD BRING MID TO UPPER 80S SFC TEMPS WITH SFC DEWPOINTS IN THE
MID 60S TO NEAR 70 DEGREE RANGE TO YIELD CAPE OF 2000 J/KG OR MORE BY
MID TO LATE AFTERNOON. LAPSE RATES IN THE MID LEVELS WILL NOT BE
PARTICULARLY STRONG AND RATHER WEAK SHEAR SHOULD LIMIT STORM
ORGANIZATION. HOWEVER... A FEW CELLS...POSSIBLY SECOND AND THIRD
GENERATION CELLS THAT DEVELOP NEAR OUTFLOW INTERSECTIONS COULD BECOME
STRONG TO LOCALLY SEVERE AND PRODUCE STRONG TO LOCALLY DAMAGING WIND
GUSTS. SPC HAS PLACED THE REGION IN A SEE TEXT AREA WITH 5 PERCENT
PROBABILITIES FOR SEVERE THUNDERSTORM CRITERIA WINDS AND THIS APPEARS
REASONABLE.
THE MAIN THREAT FROM STORMS LATER TODAY AND TONIGHT MAY END UP BEING
LOCALLY HEAVY RAINFALL RATES AS PW IS EXPECTED TO BE AT OR ABOVE THE
75TH PERCENTILE. THE PRESENCE OF THE SAGGING BOUNDARY AND THE
POTENTIAL FOR CONVECTION TO TRAIN IN SOME AREAS AS THE STEERING FLOW
MAY BECOME NEARLY PARALLEL TO THE SAGGING BOUNDARY OR OUTFLOWS COULD
LEAD TO A LOCALIZED THREAT OF FLOODING. UNCERTAINTY REMAINS IN THE
DETAILS AS FAR AS TIMING AND LOCATION. IN GENERAL...IT APPEARS THAT
AS THE SHORTWAVE WORKS INTO EASTERN KY AND THE APPALACHIANS...CONVECTION
SHOULD BE MOST WIDESPREAD DURING THE LATE AFTERNOON INTO LATE EVENING.
THE HWO HAS BEEN ADJUSTED ACCORDINGLY FOR ALL OF THESE THREATS.
THE THREAT OF SOME CONVECTION WILL LINGER EVEN INTO THE DAY ON
SATURDAY AND WILL PROBABLY FEATURE A DIURNAL UPTICK IN CONVERGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 406 AM EDT FRI JUN 20 2014
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH A TYPICAL
SUMMER PATTERN IN PLACE. A NEAR ZONAL UPPER LEVEL FLOW CONTINUES BUT
WITH THE USUAL MID LEVEL RIDGE IN THE SOUTHEAST NOW SHIFTED TOWARDS
THE WESTERN GULF OF MEXICO. BRIEF RIDGING WILL KEEP PRECIP MAINLY
DIURNALLY DRIVEN AS THE BULK OF THE SUPPORT EXITS EASTERN KENTUCKY
SATURDAY NIGHT...LEAVING ONLY SLIGHT CHANCE PRECIP INTO THE DAY ON
SUNDAY WITH THE MAX HEATING. BY MONDAY...A SIGNIFICANT SHORTWAVE
MOVES ACROSS THE PLAINS AND INTO THE OH VALLEY. THIS WAVE WILL BE THE
FOCUS OF ACTIVE WEATHER THROUGH THE MID PORTION OF THE EXTENDED.
THE MENTIONED WAVE PUSHES THROUGH ON MONDAY NIGHT AND TUESDAY
PUSHING A SURFACE COLD FRONT THROUGH. THIS FORCING AND THE WAVE
MOVING THROUGH WILL PROVIDE THE BEST CHANCE OF PRECIP ON TUESDAY AND
INTO TUESDAY NIGHT. THE EURO HINTS AT THE FRONT STALLING AND
BECOMING AN EAST WEST STATIONARY BOUNDARY ALONG SOUTHERN KY BY THE WED
AND THU TIME FRAME. THIS BECOMES AN POINT OF DEVELOPING CONVECTION
THROUGH THE LAST COUPLE DAYS OF THE EXTENDED. THE CHANCES WITH THIS
SET UP BECOME DIURNALLY DRIVEN WITH THE HEATING OF THE DAY. THE LACK
OF CONTINUITY OF GUIDANCE AND NEED TO STAY CONSISTENT WITH THE
NEIGHBORING OFFICES...LEAD TO KEEPING VALUES CLOSER TO THE ALL MODEL
BLEND SOLUTION. THE MONDAY THROUGH TUESDAY NIGHT PERIOD REMAINS A
PERIOD TO WATCH WITH THE STRONG WAVE MOVING THROUGH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 755 AM EDT FRI JUN 20 2014
ANY LINGERING VALLEY FOG SHOULD LIFT AND DISSIPATE BY 13Z. SOME
SHRA/TSRA CANNOT BE RULED OUT AT ANY POINT...BUT CHANCES APPEAR
GREATEST CLOSER TO WHEN AN UPPER LEVEL DISTURBANCE NEARS THE
REGION...GENERALLY AFTER 19Z OR 20Z THROUGH ABOUT 4Z. CONFIDENCE TIMING
IS UNCERTAIN...AND ONLY VCTS HAS BEEN USED IN TAFS AT THIS POINT.
SOME FOG MAY FORM LATE IN THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JP
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
433 AM EDT FRI JUN 20 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 359 AM EDT FRI JUN 20 2014
THE REGION REMAINS IN THE WARM SECTOR SOUTH OF A FRONTAL ZONE
EXTENDING FROM THE CAROLINAS NORTHWEST TOWARD LOW PRESSURE OVER THE
NORTHERN PLAINS AND UPPER MS VALLEY REGION. THE OVERALL FLOW ACROSS
THE CONUS ATTM IS RATHER ZONAL IN NATURE WITH MID LEVEL RIDGING
CENTERED OVER THE LOWER MS RIVER VALLEY...WITH LOW AMPLITUDE RIDGING
NORTH TOWARD THE OH RIVER VALLEY. WELL TO THE NORTHEAST OF EAST KY...
A MID LEVEL LOW AND ASSOCIATED SFC LOW THAT HAS HELPED TO PUSH THE
BOUNDARY SOUTH ALONG THE EASTERN SEABOARD TO THE CAROLINAS REMAINS
PLACE WHILE A CLOSED LOW IS WORKING ACROSS THE NORTHERN ROCKIES
TOWARD THE NORTHERN PLAINS REGION ALONG US/CANADIAN BORDER.
MEANWHILE...A SHORTWAVE TROUGH IS SLOWLY WORKING FROM THE PLAINS INTO
THE MID MS AND LOWER OH VALLEY REGION.
THE SHORTWAVE TROUGH WILL WORK INTO THE LOWER OH VALLEY REGION OVER
THE NEXT FEW HOURS AND IS POISED TO MOVE ACROSS EASTERN KY AND INTO
THE APPALACHIAN REGION LATE THIS AFTERNOON AND INTO THIS EVENING. AS
THIS SHORTWAVE APPROACHES A SFC WAVE SHOULD DEVELOP AND WORK EAST
SOUTHEAST ALONG THIS NEARLY STATIONARY BOUNDARY AND CROSS THE
APPALACHIANS TONIGHT. THIS LOW SHOULD REACH THE EASTERN SEABOARD ON
SATURDAY WITH THE TAILING COLD FRONT GRADUALLY SAGGING INTO EASTERN
KY AND CROSSING MUCH OF THE AREA BY THE END OF THE PERIOD.
THROUGH SHORTLY AFTER DAWN...PATCHY RIVER VALLEY FOG SHOULD REMAIN IN
PLACE...WITH THIS FOG GRADUALLY BEGINNING TO LIFT AND POSSIBLY
AFFECTING A FEW RIDGETOP LOCATIONS NEAR LOCATIONS THAT EXPERIENCED
THE HEAVIER RAINFALL ON THU AND THU EVENING. THIS FOG SHOULD LIFT AND
DISSIPATE SHORTLY AFTER DAWN. ALSO...THE NEAR TERM MODELS SUCH AS
RECENT HRRR RUNS AND RECENT RAP RUNS HAVE SOME CONVECTION DEVELOPING
NEAR SUNRISE BETWEEN JKL AND LOZ OR FROM ESTILL COUNTY SOUTH TO BELL
COUNTY AND THEN MOVING EAST TO NEAR THE KY 15 CORRIDOR FROM JKL SOUTH
TO THE VA BORDER AND THEN INTO FAR SOUTHEAST KY BEFORE NOON. THE 6Z
NAM ALSO HAS SOME CONVECTION...BUT IS FURTHER EAST NEAR TO THE VA
BORDER ACROSS THE BIG SANDY REGION. HOWEVER...EVEN IF THERE IS SOME
MORNING CONVECTION...JUST A FEW HOURS OF THE STRONG JUNE SUNSHINE
SHOULD BRING MID TO UPPER 80S SFC TEMPS WITH SFC DEWPOINTS IN THE
MID 60S TO NEAR 70 DEGREE RANGE TO YIELD CAPE OF 2000 J/KG OR MORE BY
MID TO LATE AFTERNOON. LAPSE RATES IN THE MID LEVELS WILL NOT BE
PARTICULARLY STRONG AND RATHER WEAK SHEAR SHOULD LIMIT STORM
ORGANIZATION. HOWEVER... A FEW CELLS...POSSIBLY SECOND AND THIRD
GENERATION CELLS THAT DEVELOP NEAR OUTFLOW INTERSECTIONS COULD BECOME
STRONG TO LOCALLY SEVERE AND PRODUCE STRONG TO LOCALLY DAMAGING WIND
GUSTS. SPC HAS PLACED THE REGION IN A SEE TEXT AREA WITH 5 PERCENT
PROBABILITIES FOR SEVERE THUNDERSTORM CRITERIA WINDS AND THIS APPEARS
REASONABLE.
THE MAIN THREAT FROM STORMS LATER TODAY AND TONIGHT MAY END UP BEING
LOCALLY HEAVY RAINFALL RATES AS PW IS EXPECTED TO BE AT OR ABOVE THE
75TH PERCENTILE. THE PRESENCE OF THE SAGGING BOUNDARY AND THE
POTENTIAL FOR CONVECTION TO TRAIN IN SOME AREAS AS THE STEERING FLOW
MAY BECOME NEARLY PARALLEL TO THE SAGGING BOUNDARY OR OUTFLOWS COULD
LEAD TO A LOCALIZED THREAT OF FLOODING. UNCERTAINTY REMAINS IN THE
DETAILS AS FAR AS TIMING AND LOCATION. IN GENERAL...IT APPEARS THAT
AS THE SHORTWAVE WORKS INTO EASTERN KY AND THE APPALACHIANS...CONVECTION
SHOULD BE MOST WIDESPREAD DURING THE LATE AFTERNOON INTO LATE EVENING.
THE HWO HAS BEEN ADJUSTED ACCORDINGLY FOR ALL OF THESE THREATS.
THE THREAT OF SOME CONVECTION WILL LINGER EVEN INTO THE DAY ON
SATURDAY AND WILL PROBABLY FEATURE A DIURNAL UPTICK IN CONVERGE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 406 AM EDT FRI JUN 20 2014
THE EXTENDED FORECAST PERIOD BEGINS ON SATURDAY NIGHT WITH A TYPICAL
SUMMER PATTERN IN PLACE. A NEAR ZONAL UPPER LEVEL FLOW CONTINUES BUT
WITH THE USUAL MID LEVEL RIDGE IN THE SOUTHEAST NOW SHIFTED TOWARDS
THE WESTERN GULF OF MEXICO. BRIEF RIDGING WILL KEEP PRECIP MAINLY
DIURNALLY DRIVEN AS THE BULK OF THE SUPPORT EXITS EASTERN KENTUCKY
SATURDAY NIGHT...LEAVING ONLY SLIGHT CHANCE PRECIP INTO THE DAY ON
SUNDAY WITH THE MAX HEATING. BY MONDAY...A SIGNIFICANT SHORTWAVE
MOVES ACROSS THE PLAINS AND INTO THE OH VALLEY. THIS WAVE WILL BE THE
FOCUS OF ACTIVE WEATHER THROUGH THE MID PORTION OF THE EXTENDED.
THE MENTIONED WAVE PUSHES THROUGH ON MONDAY NIGHT AND TUESDAY
PUSHING A SURFACE COLD FRONT THROUGH. THIS FORCING AND THE WAVE
MOVING THROUGH WILL PROVIDE THE BEST CHANCE OF PRECIP ON TUESDAY AND
INTO TUESDAY NIGHT. THE EURO HINTS AT THE FRONT STALLING AND
BECOMING AN EAST WEST STATIONARY BOUNDARY ALONG SOUTHERN KY BY THE WED
AND THU TIME FRAME. THIS BECOMES AN POINT OF DEVELOPING CONVECTION
THROUGH THE LAST COUPLE DAYS OF THE EXTENDED. THE CHANCES WITH THIS
SET UP BECOME DIURNALLY DRIVEN WITH THE HEATING OF THE DAY. THE LACK
OF CONTINUITY OF GUIDANCE AND NEED TO STAY CONSISTENT WITH THE
NEIGHBORING OFFICES...LEAD TO KEEPING VALUES CLOSER TO THE ALL MODEL
BLEND SOLUTION. THE MONDAY THROUGH TUESDAY NIGHT PERIOD REMAINS A
PERIOD TO WATCH WITH THE STRONG WAVE MOVING THROUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 200 AM EDT FRI JUN 20 2014
OUTSIDE OF LOCATIONS WITH VALLEY FOG CONDITIONS ACROSS THE REGION WERE
MOSTLY VFR. VALLEY FOG WILL CONTINUE TO DEVELOP THOUGH CURRENT
DEWPOINT DEPRESSIONS ARE RELATIVELY HIGH AT SME AND LOZ TAF SITES.
VALLEY FOG SHOULD LIFT TOWARD DAWN AT THE JKL AND SJS TAF SITES FROM
NEARBY VALLEYS. OTHERWISE...THE THICKEST VALLEY FOG SHOULD OCCUR BEING
IN AREAS WHERE RAIN FELL. ANY FOG SHOULD DISSIPATE BY 13Z. SOME
ADDITIONAL SHRA/TSRA CANNOT BE RULED OUT AFTER ABOUT 8Z OR 9Z...BUT
THE PROBABILITY IS TOO LOW TO INCLUDE IN THE TAFS UNTIL CLOSER TO 15Z
TO 16Z. HOWEVER...TIMING IS UNCERTAIN...AND ONLY VCTS HAS BEEN USED
IN TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
231 AM EDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 200 AM EDT FRI JUN 20 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT SATELLITE AND
RADAR TRENDS. THE RECENT HRRR AND RAP RUNS HAVE ALSO BEEN FACTORED
IN. CONVECTION HAS DWINDLED OVERNIGHT AND THIS TREND SHOULD CONTINUE
OVER THE NEXT COUPLE OF HOURS. HOWEVER...SOME OF THE GUIDANCE POINTS
TOWARD SOME REDEVELOPMENT OF ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS JUST PRIOR TO DAWN. OTHERWISE...SOME VALLEY LOCATIONS
SUCH AS I35 ARE EXPERIENCING DENSE FOG AND OTHER VALLEY LOCATIONS
WILL LIKELY FOLLOW AS LONG AS THE CLOUD COVER CONTINUES TO THIN.
UPDATE ISSUED AT 1051 PM EDT THU JUN 19 2014
EARLIER CONVECTION HAS LEFT ONLY A BIT OF LIGHT RAIN AS A REMNANT...
AND THIS WAS ON THE DECLINE. THE HRRR...RUC...AND NAM FROM THIS
EVENING ALL STILL SUGGEST SOME LIMITED REDEVELOPMENT OF CONVECTION
OVERNIGHT IN THE WARM AIR ADVECTION REGIME. THERE ARE SOME CELLS
WHICH HAVE POPPED UP OVER SOUTH CENTRAL KY. WILL LEAVE LOW POPS IN
PLACE OVERNIGHT.
UPDATE ISSUED AT 853 PM EDT THU JUN 19 2014
CONVECTIVE DEVELOPMENT TRENDS HAVE BEEN DIFFICULT TO PIN DOWN THIS
AFTERNOON AND EVENING. THE LATEST AREA OF ORGANIZED STORMS TO DEVELOP
HAVE BEEN JUST NORTH OF THE MOUNTAIN PARKWAY NEAR/AHEAD OF THE
REMNANT OUTFLOW BOUNDARY FROM EARLIER CONVECTION FURTHER
NORTH...WHICH IS ALSO THE EFFECTIVE FRONTAL BOUNDARY. HAVE SET AN
AREA OF LIKELY POPS FOR THIS FOR A COUPLE OF HOURS AS THE CONVECTION
DRIFTS/DEVELOPS SOUTHWARD. STILL THINK THAT ACTIVITY WILL BE ON AN
OVERALL DECLINE THIS EVENING WITH LOSS OF HEATING. MODELS TRY TO SHOW
SOME REDEVELOPMENT OVERNIGHT IN A WEAK WARM AIR ADVECTION REGIME
SENDING THE FRONT BACK NE. CONFIDENCE FOR PRECIP OVERNIGHT IS
LOW...AND THE EXISTING LOW POPS FOR THE OVERNIGHT HOURS SEEM
REASONABLE.
UPDATE ISSUED AT 602 PM EDT THU JUN 19 2014
CONVECTION HAS BEEN ON THE INCREASE OVER THE NORTHEAST PART OF THE
JKL FORECAST AREA...WHERE A NUMBER OF OUTFLOW BOUNDARIES ARE
CONVERGING. HAVE RAISED POPS TO 50 PERCENT FOR THE NEXT OUR OR TWO
FOR THAT AREA.
IN ADDITION...A LINE OF CONVECTION HAS BEEN SLOWLY SINKING SW IN
INDIANA AND OHIO THIS AFTERNOON. HOWEVER...ALONG THE PORTION NEAR THE
OHIO RIVER...THE OUTFLOW APPEARS TO BE MOVING FURTHER OUT AHEAD OF
THE STORMS...AND THE CONVECTIVE LINE IS LOOKING MORE BROKEN AND LESS
INTENSE THAN EARLIER. WITH THESE TRENDS...IT IS QUESTIONABLE HOW
INTACT IT WILL BE IF IT MAKES IT TO THE JKL FORECAST AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 435 PM EDT THU JUN 19 2014
ISOLD TO SCATTERED CONVECTION CONTINUES TO FIRE ACROSS PORTIONS OF THE
FORECAST AREA THIS AFTERNOON. A COUPLE STORMS HAVE BEEN SHOWING SOME
FAIRLY STRONG SIGNATURES...BUT HAVE NOT SEEN MUCH IN THE WAY OF
WINDS AND NO REPORTS OF HAIL. BUT THE NATURE OF THE COVERAGE MAY BE
LIMITING REPORTS. STRONGEST CONVECTION ATTM IS LOCATED IN OUR
NORTHEASTERN COUNTIES...ALONG ONE OF THE PREDOMINANT BOUNDARIES.
SOME CONVECTION HAS BEEN TRIGGERED IN THE WEST AS WELL...ALONG AN
OUTFLOW THAT IS PUSHING TO THE EAST. THESE OUTFLOWS HAVE BEEN
STABILIZING THE BOUNDARY LAYER AS THEY PASS THROUGH ANY GIVEN
AREA...AND IT HAS BEEN TAKING TIME FOR THE SUN TO HEAT THINGS UP
ENOUGH TO GET ADDITIONAL INSTABILITY FOR REDEVELOPMENT. WITH SUNSET
APPROACHING AND A THICKER CIRRUS SHIELD MOVING UP FROM THE SOUTH...
EXPECT CONVECTION WILL BECOME MORE LIMITED WITH TIME THROUGH THE
REMAINDER OF THE LATE AFTERNOON AND EARLY EVENING HOURS.
SHOWERS AND THUNDERSTORMS WILL REDEVELOP TOMORROW AS A FRONTAL SYSTEM
APPROACHES FROM THE WEST. ANY THUNDERSTORMS THAT DO DEVELOP COULD
DISPLAY SOME STRONG CHARACTERISTICS AND CAN NOT RULE OUT A SEVERE
STORM OR TWO. WE COULD ALSO SEE SOME HEAVY RAINERS...ESPECIALLY AS WE
GET INTO FRIDAY AND FRIDAY EVENING. PWATS ARE HIGH CLIMATOLOGICALLY
SPEAKING AND STORM MOTION ARE RELATIVELY LOW...5-10KTS. FREEZING
LEVELS REMAIN HIGH BETWEEN 14-15K AS WELL. SO WARM WATER PROCESSES
COULD BE A FACTOR AS WELL. ALSO...THREAT WOULD BE HIGHER WHERE ANY
BOUNDARIES SET UP...SHOULD THAT LEAD TO TRAINING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 316 PM EDT THU JUN 19 2014
EASTERN KY WILL FIND ITSELF ON THE BACK EDGE OF A DEAMPLIFIED
RIDGING PATTERN AT THE BEGINNING OF THE PERIOD /12Z SATURDAY/...WITH
A SHORTWAVE PASSING THROUGH THE REGION AND A SURFACE BOUNDARY IN THE
FORM OF A BACKDOOR COLD FRONT CAUSING SHOWERS AND THUNDERSTORMS TO
LINGER...ESPECIALLY ACROSS THE SE PORTION OF THE CWA. THE NAM IS THE
ONLY MODEL AT THIS POINT WHICH DOES NOT PUT PRECIP COVERAGE ACROSS
MUCH OF THE CWA...SO HAVE SLIGHTLY LOWER CONFIDENCE DURING THIS TIME
PERIOD FOR THE MODEL. EXPECT BEST COVERAGE TO BE IN THE
MORNING...THEN TAPERING OFF AS THE SURFACE LOW SLOWLY PUSHES
SOUTHWARD. CHANCES WILL LINGER LONGEST OVER THE SE PORTION OF THE
STATE WITH LINGERING LOW LEVEL MOISTURE AND UPSLOPE FLOW. THE UPPER
LEVEL SHORTWAVE WILL CONTINUE TO SLOWLY SLIDE EASTWARD SATURDAY
NIGHT AND SUNDAY...AS THE OVERALL UPPER FLOW BECOMES SLIGHTLY MORE
ZONAL. THIS WILL ELIMINATE THE BEST PRECIP CHANCES OVERNIGHT
SATURDAY...THOUGH LINGERING MOISTURE AND DAYTIME INSTABILITY COULD
POP UP SOME MORE DIURNALLY DRIVEN SCATTERED SHOWERS AND
THUNDERSTORMS DURING THE DAY SUNDAY. A MORE NORTHERLY FLOW BOTH
SATURDAY AND SUNDAY WILL KEEP DAYTIME TEMPERATURES SLIGHTLY COOLER
THAN PREVIOUS DAYS...IN THE LOW TO MID 80S ACROSS MUCH OF THE CWA.
DIURNALLY DRIVEN SCATTERED SHOWERS AND THUNDERSTORMS COULD BE
POSSIBLE INTO THE DAY MONDAY AS WELL...WHILE WEAK UPPER LEVEL
RIDGING REMAINS OVERHEAD. HOWEVER...BOTH THE GEM AND ECMWF ARE ONLY
SHOWING DEVELOPMENT ACROSS THE FAR SE COUNTIES...WHILE THE GFS IS
SHOWING A VAST AMOUNT OF PRECIP ACROSS MUCH OF KENTUCKY. GIVEN THE
SYNOPTIC SET UP...WOULD CHOSE TO SIDE CLOSER TO THE ECMWF...WITH THE
GFS PULLING IN AN UNREALISTIC AMOUNT OF MOISTURE ACROSS THE REGION.
BY LATE MONDAY...AN UPPER LEVEL LOW IN SOUTH CENTRAL CANADA WILL
BEGIN TO DEEPEN...PULLING A DEEPENING TROUGH INTO THE MISSISSIPPI
RIVER VALLEY OVERNIGHT MONDAY NIGHT. AS THIS LOW SHIFTS EASTWARD...
EXPECT A SURFACE LOW AND BOUNDARY TO IMPACT THE REGION DURING THE DAY
TUESDAY. MODELS AT THIS POINT ARE CONTINUING TO DISAGREE IN THEIR
SOLUTIONS...SO WILL STICK CLOSE TO A BLEND OF SOLUTIONS FROM THIS
POINT FORWARD. AS THIS SYSTEM APPROACHES...SOUTHERLY FLOW WILL
REESTABLISH ITSELF...BRINGING IN A WARMER AND MORE HUMID/UNSTABLE AIR
MASS. SHOWERS AND THUNDERSTORMS COULD BE POSSIBLE FROM TUESDAY WELL
INTO THE DAY WEDNESDAY AS THE SURFACE FRONT BECOMES MORE WEST TO EAST
ORIENTED ACROSS KENTUCKY. A BRIEF BREAK MIGHT BE FELT SOMETIME EARLY
THURSDAY...HOWEVER ANOTHER SHORTWAVE WILL BE FAST TO BRING YET
ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS TO FINISH OUT THE 7 DAY
FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 200 AM EDT FRI JUN 20 2014
OUTSIDE OF LOCATIONS WITH VALLEY FOG CONDITIONS ACROSS THE REGION WERE
MOSTLY VFR. VALLEY FOG WILL CONTINUE TO DEVELOP THOUGH CURRENT
DEWPOINT DEPRESSIONS ARE RELATIVELY HIGH AT SME AND LOZ TAF SITES.
VALLEY FOG SHOULD LIFT TOWARD DAWN AT THE JKL AND SJS TAF SITES FROM
NEARBY VALLEYS. OTHERWISE...THE THICKEST VALLEY FOG SHOULD OCCUR BEING
IN AREAS WHERE RAIN FELL. ANY FOG SHOULD DISSIPATE BY 13Z. SOME
ADDITIONAL SHRA/TSRA CANNOT BE RULED OUT AFTER ABOUT 8Z OR 9Z...BUT
THE PROBABILITY IS TOO LOW TO INCLUDE IN THE TAFS UNTIL CLOSER TO 15Z
TO 16Z. HOWEVER...TIMING IS UNCERTAIN...AND ONLY VCTS HAS BEEN USED
IN TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...RAY
LONG TERM...JMW
AVIATION...JP
AREA FORECAST DISCUSSION
NWS CARIBOU ME
925 PM EDT SAT JUN 21 2014
.SYNOPSIS...
WEAK LOW PRESSURE WILL REMAIN TO OUR EAST THROUGH TONIGHT. AN
UPPER DISTURBANCE WILL CROSS THE REGION SUNDAY. HIGH PRESSURE
WILL CROSS THE REGION MONDAY.&&
.NEAR TERM /THROUGH SUNDAY/...
930 PM UPDATE: WSR-88D RADAR CONTINUED TO INDICATE LIGHT RAIN
SHOWERS GENERALLY STRETCHING FROM NORTHERN PORTIONS OF PISCATAQUIS
AND PENOBSCOT COUNTIES TO CENTRAL AND SOUTHERN AROOSTOOK COUNTY
THIS EVENING. THE HRRR MODEL HAS A GOOD HANDLE AND HAS THIS AREA
OF SHOWERS SLOWLY PROGRESSING SOUTH BEFORE DECAYING AS WE GO
THROUGH THE LATE EVENING HOURS. MADE SOME ADJUSTMENTS TO CURRENT
CONDITIONS AND ADJUSTED POP GRIDS TO MATCH THE CURRENT RADAR/GUIDANCE
TRENDS.
PREVIOUS DISCUSSION...THE UPPER LEVEL DISTURBANCE WILL MOVE EAST LATER
THIS EVENING WITH SKIES REMAINING PARTLY TO MOSTLY CLOUDY ACROSS
THE REGION TONIGHT. LOWS TONIGHT WILL RANGE FROM THE MID 40S TO
THE LOWER 50S.
ANOTHER UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING SUNDAY.
THIS DISTURBANCE WILL BRING THE CHANCE FOR A SHOWER DURING SUNDAY
AFTERNOON AS IT CROSSES THE REGION. THE BEST CHANCES WILL BE
ACROSS PORTIONS OF CENTRAL AND INTERIOR DOWNEAST WHERE THERE COULD
EVEN BE THE CHANCE FOR A THUNDERSTORM WHERE THE BETTER INSTABILITY
WILL EXIST. HIGH TEMPERATURES ON SUNDAY WILL BE IN THE LOW TO MID
70S NORTH AND MID TO UPPER 70S DOWNEAST.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
ANY REMAINING SHOWERS SUNDAY EVENING SHOULD QUICKLY DIE OFF AS THE
SUN SETS AND AS THE UPPER LEVEL SHORTWAVE PASSES TO OUR EAST.
MONDAY IS LOOKING LIKE A GENERALLY PARTLY CLOUDY DAY WITH ISOLATED
SHOWERS IN THE AFTERNOON AND TEMPERATURES A FEW DEGREES ABOVE
AVERAGE.
FOR TUESDAY, HOWEVER, WESTERLY UPPER LEVEL FLOW AND LOW LEVEL
SOUTHERLY FLOW INCREASE AS A FRONT APPROACHES MAINE FROM THE WEST.
A BETTER CHANCE OF SOME AFTERNOON AND EVENING SHOWERS AND STORMS
TUESDAY MAINLY INLAND AND AWAY FROM THE MARINE LAYER.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
FRONTAL SYSTEM EXPECTED TO MOVE THROUGH TUESDAY NIGHT OR WEDNESDAY
WITH SHOWERS LIKELY AND POSSIBLY SOME STORMS. LOOK FOR THE FRONT
TO CLEAR THE COAST WEDNESDAY NIGHT. NOT LOOKING FOR MUCH OF A
COOLDOWN BEHIND THE FRONT WITH TEMPERATURES REMAINING A BIT WARMER
THAN AVERAGE THURSDAY THROUGH THE WEEKEND. NO MAJOR PRECIPITATION
CHANCES, BUT THERE COULD BE A FEW AFTERNOON AND EVENING SHOWERS
AND POSSIBLY STORMS ANY DAY THURSDAY THROUGH THE WEEKEND.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR THROUGH SUNDAY.
SHORT TERM: VFR EXPECTED MONDAY AND TUESDAY. POSSIBLE MVFR OR LOWER
TUESDAY NIGHT INTO WEDNESDAY EVENING AS A FRONT MOVES THROUGH THE
AREA FROM NORTHWEST TO SOUTHEAST.
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS THROUGH SUNDAY.
SHORT TERM: EXPECT WINDS AND SEAS TO INCREASE TO SMALL CRAFT
LEVELS TUESDAY AND TUESDAY NIGHT AS A FRONT APPROACHES. WINDS WILL
BE ONSHORE WITH FREQUENT GUSTS NEAR OR A BIT ABOVE 25 KNOTS AND SEAS
BUILDING TO 4 TO 7 FEET. WINDS ARE EXPECTED TO DROP BACK BELOW
SMALL CRAFT LEVELS LATE WEDNESDAY OR WEDNESDAY NIGHT AS THE FRONT
PASSES THROUGH, THOUGH SEAS PROBABLY WON`T DROP BELOW 5 FEET UNTIL
AROUND LATE THURSDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DUDA/JORDAN
SHORT TERM...FOISY
LONG TERM...FOISY
AVIATION...DUDA/JORDAN/FOISY
MARINE...DUDA/JORDAN/FOISY
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1043 PM EDT SAT JUN 21 2014
.SYNOPSIS...
A WAVE OF LOW PRESSURE RIDING ALONG A FRONTAL BOUNDARY OVER SOUTHERN
VIRGINIA WILL CONTINUE TO PROGRESS SOUTHWARD TONIGHT. HIGH PRESSURE
WILL FILL IN OVER THE AREA SUNDAY BEFORE MOVING OFF THE COAST
THROUGH THE BEGINNING OF THE WORKWEEK. A FRONTAL BOUNDARY WILL
APPROACH THE AREA ON WEDNESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
MSAS AND SURFACE OBS INDICATE COLD FRONT NEAR THE VA/NC
BORDER...WITH SEVERAL WAVES OF LOW PRESSURE ALONG IT. ONE IMPULSE...WHICH
CONTRIBUTED TO THUNDERSTORMS WITH HEAVY RAINFALL OVER THE
PIEDMONT LATE SUNDAY AFTERNOON...HAS MOVED INTO THE PIEDMONT AND
SRN MARYLAND. LIGHT SCATTERED SHOWER ACTIVITY HAS DEVELOPED IN
THESE AREAS. HRRR HAS CAPTURED THIS PRETTY WELL. IT IS EXPECTED TO
MOVE INTO THE NORTHERN NECK OVER THE NEXT FEW HOURS AND MAY LINGER
OVER SRN MD OVERNIGHT.
A LIGHT SFC WIND FIELD FOR TONIGHT WILL LEAD TO LOWER CIGS AND
VSBYS WITH PATCHY FOG FORMING...ESP IN AREAS THAT RECEIVE THE
SHRA/TSTM ACTIVITY THIS AFTERNOON AND EVENING. TEMPS WILL RANGE
FROM THE MID 50S ALONG THE MASON-DIXON LINE TO THE LOWER 60S IN
THE URBAN AREAS AND SOUTHERN CWA TIER.
SUNDAY WILL BE A TAD BETTER FOR OUTDOOR PLANS THAN TODAY WAS...AS
OCEAN FLOW CONTINUES THAT WILL CAUSE STABLE CONDITIONS FROM THE
BLUE RIDGE TO THE CHESAPEAKE. ONCE AGAIN...THE CENTRAL SHENANDOAH
VALLEY AND AREAS WEST WILL BE UNSTABLE AS EVIDENCED BY THE 12Z GFS
THAT GIVES SFC CAPES NEARING 1000 J/KG...WHICH WOULD GIVE THIS
AREA A GENERAL THUNDER THREAT AND NOT SEVERE. SKY COVER SHOULD NOT
BE AS PRONOUNCED AS TODAY AS THE 12Z GFS 1000-700 MB RH SHOWS MORE
CLOUD BREAKS ESP IN THE NE 1/3RD CWA...THUS INCREASING MAX TEMPS
TO THE LOWER 80S. USED A BLEND OF MOS GUIDANCE BIAS CORRECTED AND
SREF BIAS CORRECTED IN COMING UP WITH MAX TEMPS FOR SUNDAY.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
UNREMARKABLE WEATHER FOR MUCH OF AREA DURING THIS PD IN E/SE FLOW
AROUND SFC HIGH PRESSURE E OF NEW ENGLAND. ONLY EXCEPTION IS WEST
OF THE BLUE RIDGE WHERE THE INFLUENCE OF MARINE AIR IS LIMITED AS
SOUTHERLIES DEVELOP THERE SUNDAY NIGHT.
TUESDAY THE REGION GETS INTO SW FLOW...ALONG WITH A TIGHTER SFC
PRESSURE GRADIENT...SHEAR...AND INSTABILITY. THIS LOOKS TO BE ATTM
A POTENTIALLY LOW-END SEVERE WEATHER DAY...WITH 12Z GFS CAPES
APPROACHING 2250 J/KG ALONG AND W OF INTERSTATE 95.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A BROAD LOW MAGNITUDE UPPER LEVEL TROUGH WILL MOVE OVER THE EASTERN
US DURING THE MIDDLE OF NEXT WEEK. SURFACE LOW PRESSURE TRACKING FROM
THE GREAT LAKES TOWARD NOVA SCOTIA WILL DRAG A COLD FRONT THROUGH
OUR AREA DURING THE DAY AND POSSIBLY INTO THE NIGHT WEDNESDAY.
INSTABILITY AND MOISTURE...PW NEAR 2 INCHES...SHOULD BE PLENTIFUL
AHEAD OF THE BOUNDARY TO BRING THUNDERSTORMS ACROSS THE AREA
WEDNESDAY. HAVE PUT LIKELY POPS INTO THE FORECAST FOR MUCH OF THE
CWA.
THE FRONTAL BOUNDARY WILL STALL JUST EAST AND SOUTH OF THE AREA ON
THURSDAY. A WAVE OF LOW PRESSURE WILL FORM ALONG THE BOUNDARY AND
REMAIN PARKED OVER THE CAROLINAS INTO THE WEEKEND. THERE IS
CONSIDERABLE MODEL DIVERGENCE IN TERMS OF THE SYNOPTIC SET UP FOR
THE END OF NEXT WORKWEEK. THE GFS DEVELOPS HIGH PRESSURE NEAR CAPE
COD...WHICH IN CONJUNCTION WITH THE LOW OVER THE CAROLINAS WOULD
BRING A MARINE LAYER...LOW CEILINGS AND COOL AIR...INTO THE
MID-ATLANTIC THURSDAY. THE EURO DOES NOT DEVELOP THIS HIGH...AND IN
TURN RESOLVES MUCH WEAKER ADVECTION OF MARINE AIR.
THE OVERALL PATTERN WILL BE WEAK FLOW LOCALLY AND DIURNAL
INSTABILITY FOR THURSDAY FRIDAY AND SATURDAY. WITH ONLY MODEST
INSTABILITY ANTICIPATED AND THE THREAT FOR MARINE AIR TO ENCROACH
FROM THE EAST...HAVE LEFT CHANCE POPS TO ACCOUNT FOR AFTERNOON
CONVECTION FOR THE END OF THE WEEK WITH LOWER POPS ALONG THE BAY
WHERE MARINE AIR MAY THREATEN. HIGH TEMPS WILL BE NEAR NORMAL IN THE
MID TO UPPER 80S THROUGH THE LONG TERM.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
MVFR CONDITIONS EXPECTED OVER BALTIMORE/WASHINGTON AREA TERMINALS
AND KMRB TONIGHT DUE TO ABUNDANT LOW LEVEL MOISTURE. SIMILAR
SITUATION AT KCHO...WHERE IFR CIGS DEVELOPED AT 23Z. CIGS AT KCHO
MAY IMPROVE FOR A WHILE THIS EVENING...BUT SOME LIGHT SHOWER
ACTIVITY MAY MOVE THROUGH THE AREA...FOLLOWED BY RENEWED FOG AND
LOW CIGS TONIGHT. IMPROVEMENT TO VFR EXPECTED SUNDAY MORNING.
LIGHT N-NE WINDS EXPECTED.
WILL BE DEALING WITH MVFR CIGS AND VSBYS AT KMRB AND KCHO AGAIN
SUN NIGHT...AND MON NIGHT WITH LIGHT WIND FIELD...OCEAN
FLOW...AND INVERSION. KIAD MAY DROP TO MVFR SUN NIGHT AS WELL. WINDS
LIGHT E/NE/VRBLE FOR THE NEXT 36-48 HOURS.
TUE AND WED MVFR/IFR CONDITIONS ARE POSSIBLE FOR CIGS AND VSBYS IN
SHOWERS AND THUNDERSTORMS...AS A COLD FRONT APPROACHES TUE THEN
MOVES THROUGH THE AREA WED.
&&
.MARINE...
NE-E WINDS THIS EVENING OVER THE WATERS. SOME GUSTS INTO THE
TEENS...BUT SCA CONDITIONS ARE NOT EXPECTED.
NO MARINE HAZARDS XPCTD UNTIL TUE WHEN A SMALL CRAFT ADVISORY MAY
BE NEEDED IN PREFRONTAL S/SW FLOW TUESDAY AFTERNOON AND THEN AGAIN
WEDNESDAY WITH FROPA.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CEB
NEAR TERM...LEE/KCS
SHORT TERM...LEE
LONG TERM...CEB
AVIATION...KCS/CEB
MARINE...LEE/KCS/CEB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1242 PM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CDT FRI JUN 20 2014
FIRST CONCERNS IS DENSE FOG ADV ACROSS MPX CWA. SECONDARY CONCERN IS
ISOLD/SCT CONVECTION ALONG AN INSTABILITY AXIS MOVING ACROSS MN THIS
AFTN.
PLENTY OF RAINFALL OVER THE LAST 24 HRS FOR BOUNDARY LAYER TO
SATURATE. HOWEVER...BOUNDARY LAYER WINDS INCREASED SLIGHTLY AFT
MIDNIGHT ALLOWING FOR MAINLY LOW STRATUS AND PATCHY DENSE FOG ACROSS
SC MN...BUT THE MAJORITY OF MPX CWA HAD PATCHY FOG WITH LOCALIZED
DENSE FOG WHERE CIGS DROPPED TO 100-200`. BASED ON CURRENT VIS/FOG
SATELLITE IMAGERY AND BOUNDARY LAYER WINDS ARND 5-10 KTS ANTICIPATE
THAT THE DENSE FOG ADV WILL BE CANCELLED EARLY...PROBABLY BEFORE
SUNRISE. WILL MONITOR FOR ANY NEW DEVELOPMENT ACROSS SC/EC MN FOR
CIGS/VSBYS DROPPING LOWER...BUT THIS IS NOT EXPECTED TO CAUSE
WIDESPREAD DENSE FOG...ONLY PATCHY DENSE FOG.
A COUPLE OF ITEMS TO NOTE EARLY THIS MORNING FOR THE POTENTIAL OF
CONVECTION THIS AFTN. FIRST...A WEAK SHRTWV ROTATING ARND THE
SOUTHERN PART OF THE MAIN UPPER LOW ACROSS SOUTH CENTRAL CANADA WILL
LIKELY PROVIDE SOME LIFT LATER THIS AFTN ACROSS MN. RUC DOES SHOW
85/92H WINDS BECOMING MORE SSW/SW THIS AFTN ACROSS NE/SD WHICH WILL
PULL RESIDUAL MOISTURE ACROSS KS/CO NE INTO SW MN DURING THE AFTN.
MLCAPES AND MLCIN REFLECT THE CHC/S THIS AFTN IN A THIN BAND FROM SW
TO CENTRAL MN. DUE TO WEAK SFC CONVERGENCE AND GREATER SHRTWV
STRENGTH ACROSS NORTHERN MN...ONLY ISOLD/SCT SHRA/TSRA WILL BE
POSSIBLE. 20-30% SEEMS REASONABLE AT THIS TIME. LATER SHIFTS WILL
NEED TO MONITOR FOR HIGHER MOISTURE ADVECTING NE ACROSS S MN. THE
SAME SW WINDS IN THE FIRST 5K ACROSS SD AND INTO WC MN THIS AFTN MAY
CAUSE ENOUGH MIXING TO HAVE TEMPS RISE INTO THE LOWER 90S. BUT BASED
ON THE WET SOIL CONDS AND DEW PTS IN THE 50S/60S...AM LEANING TOWARD
MID TO UPPER 80S AT THIS TIME. TONIGHT WILL LIKELY SEE THE
CONVECTION DECREASING RAPIDLY AFT SUNSET WITH MOST OF THE ACTION
SOUTH OF THE MN AS THE LLJ DEVELOPS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI JUN 20 2014
THERE COULD BE AN ONGOING MCS IN NORTHEAST NE OR NORTHERN IA COME
12Z SATURDAY MORNING WITH THE AFOREMENTIONED INCREASING LLJ...BUT
THE 850-300MB WINDS AND THICKNESS PATTERN SUGGEST ANY ORGANIZED
/OR UNORGANIZED CONVECTION FOR THAT MATTER/ SHOULD TRACK E-SE
WITH TIME AND REMAIN SOUTH OF THE FORECAST AREA THROUGH THE
MORNING HOURS. EVEN MOST OF THE CLOUD DEBRIS SHOULD BE CARRIED
DOWNSTREAM TO THE EAST. THE NAM/GFS/ECMWF ALL SEEM TO BE DEPICTING
A WEAK TROUGH IN WESTERN WI AND LIGHT QPF. THE SOUNDINGS ARE
FAIRLY DRY ON SATURDAY AND THERE ISN`T A CLEAR TRIGGER OUTSIDE OF
PERHAPS A WEAK MID LEVEL WAVE IN IA. THERE IS MODEST ELEVATED
INSTABILITY AND EVEN THE ECMWF DOES HINT AT CONVECTIVE
INITIATION...BUT THE SHOWER/THUNDER CHANCES LOOK BETTER SOUTH AND
EAST OF THE FORECAST AREA. SUNDAY IS PERHAPS A LITTLE MORE
INTERESTING AND SUGGESTS A NEED FOR SLIGHTLY HIGHER POPS AS AN
ADVANCING SURFACE BOUNDARY TRIES TO MAKE IT ACROSS MINNESOTA
DURING THE DAY WITH A SHORTWAVE APPROACHING FROM THE CENTRAL
PLAINS. ALTHOUGH PERHAPS A LITTLE OVERDONE WITH SURFACE
DEWPOINTS...BOTH THE NAM-GFS HAVE LARGE MUCAPE VALUES OF 3000-5000
J/KG IN SOUTHERN MINNESOTA. THE SHEAR PROFILE IS WEAK...WHICH WILL
SUPPRESS THE THREAT FOR SEVERE WEATHER. THERE IS ALSO UNCERTAINTY
AS TO HOW MUCH CONVECTION THERE WILL BE...BUT GIVEN THE LARGE
AMOUNT OF INSTABILITY...PULSE STORMS AND SMALL MULTICELL CLUSTERS
COULD STILL POSE A MARGINAL SEVERE THREAT IF EVERYTHING PANS OUT.
THE BEST CHANCE FOR MORE WIDESPREAD RAIN IN THE AVAILABLE MODEL
GUIDANCE IS MONDAY AFTERNOON INTO EARLY TUESDAY MORNING WITH A
DEVELOPING SURFACE CYCLONE TRACKING OUT OF THE SOUTHERN PLAINS AND
DEEPENING WITH TIME AS IT HEADS TOWARD IA/WI. THERE IS A BIT MORE
CONFIDENCE IN PRECIP AT LEAST ACROSS THE EASTERN PORTIONS OF THE
FORECAST AREA BECAUSE THE GFS/ECMWF SOLUTIONS HAVE SETTLED DOWN
OVER THE PAST 3-4 MODEL CYCLES. PREVIOUS RUNS THIS WEEK WERE ALL
OVER THE PLACE WITH PLACEMENT AND TIMING. OTHERWISE WE`LL REMAIN IN
A FAIRLY INNOCUOUS /AT LEAST COMPARED TO THE HEAVY RAIN PATTERN
WE`VE BEEN IN RECENTLY/ WESTERLY FLOW THROUGH NEXT WEEK WITH NO
BIG SYSTEMS...SEVERE WEATHER OUTBREAKS...BIG TEMPERATURES
SWINGS...ETC.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1242 PM CDT FRI JUN 20 2014
CEILINGS CONTINUE TO LIFT/DISSIPATE ALONG AND EAST OF THE MN/WI
BORDER EARLY THIS AFTERNOON. THE CU RULE IS FORECAST TO BECOME
RATHER POSITIVE AS THE AFTERNOON PROGRESSES...SO ONLY TEMPORARY
MVFR CIGS AT KRNH AND KEAU EARLY. A THREAT FOR STRONG TO SEVERE
STORMS REMAINS ACROSS CENTRAL MN AND ADJOINING AREAS OF WEST
CENTRAL WI LATE TODAY/EARLY TONIGHT. SHORT TERM SOLUTIONS ARE IN
AGREEMENT ON KEEPING THIS ACTIVITY TO THE NORTH OF KAXN...KSTC AND
KRNH. SURFACE WINDS WILL BE ON THE INCREASE FROM THE SSE THIS
AFTERNOON AS THE PRESSURE GRADIENT TIGHTENS. A CONCERN OVERNIGHT
IS DENSE FOG. BUFKIT NAM PROFILE DATA SHOWS THE BEST THREAT AREA
TO BE ACROSS FAR EASTERN MN AND WEST CENTRAL WI WHERE WINDS ARE
LIGHTEST...SATURATION THE GREATEST ALONG WITH A FAVORABLE LOW
LEVEL HYDROLAPSE. INDICATED 1/2SM FG FOR KEAU BEFORE DAYBREAK WITH
2SM BR FOR KRNH AND 3SM BR FOR KSTC. ONE THING THAT COULD DERAIL
THE DENSE FOG OVERNIGHT IS THE CI/CS BLOW OFF FROM STORMS
DEVELOPING/MOVING ACROSS NE/IA.
KMSP..A VFR AFTN WITH WINDS INCREASING FROM THE SSE. STORMS
EXPECTED TO STAY WELL NORTH OF THE AIRFIELD THIS EVENING. KEPT THE
FOG THREAT TO A MINIMUM FOR SATURDAY MORNING WITH MID/HIGH LEVEL
CLOUDINESS POSSIBLE ACROSS THE AREA WHICH WILL AID IN DIMINISHING
LOW LEVEL SATURATION.
/OUTLOOK FOR KMSP/
SUN...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS SE 10 KTS.
MON...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS NW 10 KTS.
TUE...VFR. WINDS NW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...CLF
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
556 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CDT FRI JUN 20 2014
FIRST CONCERNS IS DENSE FOG ADV ACROSS MPX CWA. SECONDARY CONCERN IS
ISOLD/SCT CONVECTION ALONG AN INSTABILITY AXIS MOVING ACROSS MN THIS
AFTN.
PLENTY OF RAINFALL OVER THE LAST 24 HRS FOR BOUNDARY LAYER TO
SATURATE. HOWEVER...BOUNDARY LAYER WINDS INCREASED SLIGHTLY AFT
MIDNIGHT ALLOWING FOR MAINLY LOW STRATUS AND PATCHY DENSE FOG ACROSS
SC MN...BUT THE MAJORITY OF MPX CWA HAD PATCHY FOG WITH LOCALIZED
DENSE FOG WHERE CIGS DROPPED TO 100-200`. BASED ON CURRENT VIS/FOG
SATELLITE IMAGERY AND BOUNDARY LAYER WINDS ARND 5-10 KTS ANTICIPATE
THAT THE DENSE FOG ADV WILL BE CANCELLED EARLY...PROBABLY BEFORE
SUNRISE. WILL MONITOR FOR ANY NEW DEVELOPMENT ACROSS SC/EC MN FOR
CIGS/VSBYS DROPPING LOWER...BUT THIS IS NOT EXPECTED TO CAUSE
WIDESPREAD DENSE FOG...ONLY PATCHY DENSE FOG.
A COUPLE OF ITEMS TO NOTE EARLY THIS MORNING FOR THE POTENTIAL OF
CONVECTION THIS AFTN. FIRST...A WEAK SHRTWV ROTATING ARND THE
SOUTHERN PART OF THE MAIN UPPER LOW ACROSS SOUTH CENTRAL CANADA WILL
LIKELY PROVIDE SOME LIFT LATER THIS AFTN ACROSS MN. RUC DOES SHOW
85/92H WINDS BECOMING MORE SSW/SW THIS AFTN ACROSS NE/SD WHICH WILL
PULL RESIDUAL MOISTURE ACROSS KS/CO NE INTO SW MN DURING THE AFTN.
MLCAPES AND MLCIN REFLECT THE CHC/S THIS AFTN IN A THIN BAND FROM SW
TO CENTRAL MN. DUE TO WEAK SFC CONVERGENCE AND GREATER SHRTWV
STRENGTH ACROSS NORTHERN MN...ONLY ISOLD/SCT SHRA/TSRA WILL BE
POSSIBLE. 20-30% SEEMS REASONABLE AT THIS TIME. LATER SHIFTS WILL
NEED TO MONITOR FOR HIGHER MOISTURE ADVECTING NE ACROSS S MN. THE
SAME SW WINDS IN THE FIRST 5K ACROSS SD AND INTO WC MN THIS AFTN MAY
CAUSE ENOUGH MIXING TO HAVE TEMPS RISE INTO THE LOWER 90S. BUT BASED
ON THE WET SOIL CONDS AND DEW PTS IN THE 50S/60S...AM LEANING TOWARD
MID TO UPPER 80S AT THIS TIME. TONIGHT WILL LIKELY SEE THE
CONVECTION DECREASING RAPIDLY AFT SUNSET WITH MOST OF THE ACTION
SOUTH OF THE MN AS THE LLJ DEVELOPS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI JUN 20 2014
THERE COULD BE AN ONGOING MCS IN NORTHEAST NE OR NORTHERN IA COME
12Z SATURDAY MORNING WITH THE AFOREMENTIONED INCREASING LLJ...BUT
THE 850-300MB WINDS AND THICKNESS PATTERN SUGGEST ANY ORGANIZED
/OR UNORGANIZED CONVECTION FOR THAT MATTER/ SHOULD TRACK E-SE
WITH TIME AND REMAIN SOUTH OF THE FORECAST AREA THROUGH THE
MORNING HOURS. EVEN MOST OF THE CLOUD DEBRIS SHOULD BE CARRIED
DOWNSTREAM TO THE EAST. THE NAM/GFS/ECMWF ALL SEEM TO BE DEPICTING
A WEAK TROUGH IN WESTERN WI AND LIGHT QPF. THE SOUNDINGS ARE
FAIRLY DRY ON SATURDAY AND THERE ISN`T A CLEAR TRIGGER OUTSIDE OF
PERHAPS A WEAK MID LEVEL WAVE IN IA. THERE IS MODEST ELEVATED
INSTABILITY AND EVEN THE ECMWF DOES HINT AT CONVECTIVE
INITIATION...BUT THE SHOWER/THUNDER CHANCES LOOK BETTER SOUTH AND
EAST OF THE FORECAST AREA. SUNDAY IS PERHAPS A LITTLE MORE
INTERESTING AND SUGGESTS A NEED FOR SLIGHTLY HIGHER POPS AS AN
ADVANCING SURFACE BOUNDARY TRIES TO MAKE IT ACROSS MINNESOTA
DURING THE DAY WITH A SHORTWAVE APPROACHING FROM THE CENTRAL
PLAINS. ALTHOUGH PERHAPS A LITTLE OVERDONE WITH SURFACE
DEWPOINTS...BOTH THE NAM-GFS HAVE LARGE MUCAPE VALUES OF 3000-5000
J/KG IN SOUTHERN MINNESOTA. THE SHEAR PROFILE IS WEAK...WHICH WILL
SUPPRESS THE THREAT FOR SEVERE WEATHER. THERE IS ALSO UNCERTAINTY
AS TO HOW MUCH CONVECTION THERE WILL BE...BUT GIVEN THE LARGE
AMOUNT OF INSTABILITY...PULSE STORMS AND SMALL MULTICELL CLUSTERS
COULD STILL POSE A MARGINAL SEVERE THREAT IF EVERYTHING PANS OUT.
THE BEST CHANCE FOR MORE WIDESPREAD RAIN IN THE AVAILABLE MODEL
GUIDANCE IS MONDAY AFTERNOON INTO EARLY TUESDAY MORNING WITH A
DEVELOPING SURFACE CYCLONE TRACKING OUT OF THE SOUTHERN PLAINS AND
DEEPENING WITH TIME AS IT HEADS TOWARD IA/WI. THERE IS A BIT MORE
CONFIDENCE IN PRECIP AT LEAST ACROSS THE EASTERN PORTIONS OF THE
FORECAST AREA BECAUSE THE GFS/ECMWF SOLUTIONS HAVE SETTLED DOWN
OVER THE PAST 3-4 MODEL CYCLES. PREVIOUS RUNS THIS WEEK WERE ALL
OVER THE PLACE WITH PLACEMENT AND TIMING. OTHERWISE WE`LL REMAIN IN
A FAIRLY INNOCUOUS /AT LEAST COMPARED TO THE HEAVY RAIN PATTERN
WE`VE BEEN IN RECENTLY/ WESTERLY FLOW THROUGH NEXT WEEK WITH NO
BIG SYSTEMS...SEVERE WEATHER OUTBREAKS...BIG TEMPERATURES
SWINGS...ETC.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 540 AM CDT FRI JUN 20 2014
LIFR CIGS ARE COMMOM ACROSS A LARGE AREA OF MPX CWA THIS
MORNING...BUT THE MAIN CONCERN IS THE DEPTH OF THE CLDS WHICH WILL
TRANSLATE TO A FAST BURN OFF...OR LINGER INTO THE LATE MORNING AS
CURRENT BOUNDARY LAYER WINDS ARE WEAK. CONFIDENCE ACROSS SW/WC MN
WHERE THE DEPTH IS MUCH SHALLOWER IS HIGHER...AND THE BURN OFF
SHOULD BE QUICK OR WITHIN AN HR OR TWO. FURTHER TO THE
EAST...CONFIDENCE IS LOW AS ANOTHER LAYER ABV THE LOW STRATUS WILL
LIKELY LINGER FOR AN HR OR TWO. KRNH/KEAU WILL LIKELY SEE
LIFR/IFR CIGS HOLDING UNTIL 15-17Z...WITH KSTC ARND 13-14Z. WINDS
WILL REMAIN LIGHT FROM THE S/SE ARND 5 KTS...THEN BECOME MORE S/SW
THIS AFTN. AM CONCERN THAT FOG/LOW CIGS WILL DEVELOP ONCE AGAIN
TONIGHT. LATER SHIFTS WILL NEED TO SEE HOW CLEARING TRENDS AND
WIND FIELDS REMAIN. KAXN/KSTC SEEMS TO BE THE BEST CHC OF
ISOLD/SCT TSRA THIS AFTN. CONFIDENCE AND TIMING REMAIN LOW.
KMSP...
LIFR CIGS WILL LIKELY HOLD ACROSS THE AIRFIELD THRU 14Z...WITH
CONFIDENCE INCREASING FOR MVFR/VFR CONDS BETWEEN 14-15Z. STILL
BELIEVE THE DEPTH OF THE CLD DECK IS SHALLOW ARND THE TWIN CITIES
AREA AND SHOULD BREAK UP FAST BY MID MORNING. WINDS WILL BE
VARIABLE FROM THE S/SE THIS MORNING...THEN BY LATE
MORNING/AFTN...WINDS SHOULD BECOME MORE SW/SSW ARND 8-10 KTS. TSRA
CHC/S THIS AFTN ARE TOO LOW TO INTRODUCE VCTS OR CB/S. LATER
SHIFTS CAN READJUST BASE ON RADAR TRENDS IN WC MN. THERE IS A
POSSIBILITY OF IFR/LIFR CIGS/VSBYS REDEVELOPING LATER TONIGHT.
/OUTLOOK FOR KMSP/
SAT...VFR. EARLY MORNING BR/FG POSSIBLE. MVFR ISO SHRA/TSRA
POSSIBLE IN THE AFTN. WINDS SW 5-10 KTS.
SUN...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS ESE 5 KTS BECMG WNW 5-10KTS.
MON...VFR. WINDS NW 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR MNZ074>077-
082>085-091>093.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...CLF
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
437 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CDT FRI JUN 20 2014
FIRST CONCERNS IS DENSE FOG ADV ACROSS MPX CWA. SECONDARY CONCERN IS
ISOLD/SCT CONVECTION ALONG AN INSTABILITY AXIS MOVING ACROSS MN THIS
AFTN.
PLENTY OF RAINFALL OVER THE LAST 24 HRS FOR BOUNDARY LAYER TO
SATURATE. HOWEVER...BOUNDARY LAYER WINDS INCREASED SLIGHTLY AFT
MIDNIGHT ALLOWING FOR MAINLY LOW STRATUS AND PATCHY DENSE FOG ACROSS
SC MN...BUT THE MAJORITY OF MPX CWA HAD PATCHY FOG WITH LOCALIZED
DENSE FOG WHERE CIGS DROPPED TO 100-200`. BASED ON CURRENT VIS/FOG
SATELLITE IMAGERY AND BOUNDARY LAYER WINDS ARND 5-10 KTS ANTICIPATE
THAT THE DENSE FOG ADV WILL BE CANCELLED EARLY...PROBABLY BEFORE
SUNRISE. WILL MONITOR FOR ANY NEW DEVELOPMENT ACROSS SC/EC MN FOR
CIGS/VSBYS DROPPING LOWER...BUT THIS IS NOT EXPECTED TO CAUSE
WIDESPREAD DENSE FOG...ONLY PATCHY DENSE FOG.
A COUPLE OF ITEMS TO NOTE EARLY THIS MORNING FOR THE POTENTIAL OF
CONVECTION THIS AFTN. FIRST...A WEAK SHRTWV ROTATING ARND THE
SOUTHERN PART OF THE MAIN UPPER LOW ACROSS SOUTH CENTRAL CANADA WILL
LIKELY PROVIDE SOME LIFT LATER THIS AFTN ACROSS MN. RUC DOES SHOW
85/92H WINDS BECOMING MORE SSW/SW THIS AFTN ACROSS NE/SD WHICH WILL
PULL RESIDUAL MOISTURE ACROSS KS/CO NE INTO SW MN DURING THE AFTN.
MLCAPES AND MLCIN REFLECT THE CHC/S THIS AFTN IN A THIN BAND FROM SW
TO CENTRAL MN. DUE TO WEAK SFC CONVERGENCE AND GREATER SHRTWV
STRENGTH ACROSS NORTHERN MN...ONLY ISOLD/SCT SHRA/TSRA WILL BE
POSSIBLE. 20-30% SEEMS REASONABLE AT THIS TIME. LATER SHIFTS WILL
NEED TO MONITOR FOR HIGHER MOISTURE ADVECTING NE ACROSS S MN. THE
SAME SW WINDS IN THE FIRST 5K ACROSS SD AND INTO WC MN THIS AFTN MAY
CAUSE ENOUGH MIXING TO HAVE TEMPS RISE INTO THE LOWER 90S. BUT BASED
ON THE WET SOIL CONDS AND DEW PTS IN THE 50S/60S...AM LEANING TOWARD
MID TO UPPER 80S AT THIS TIME. TONIGHT WILL LIKELY SEE THE
CONVECTION DECREASING RAPIDLY AFT SUNSET WITH MOST OF THE ACTION
SOUTH OF THE MN AS THE LLJ DEVELOPS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI JUN 20 2014
THERE COULD BE AN ONGOING MCS IN NORTHEAST NE OR NORTHERN IA COME
12Z SATURDAY MORNING WITH THE AFOREMENTIONED INCREASING LLJ...BUT
THE 850-300MB WINDS AND THICKNESS PATTERN SUGGEST ANY ORGANIZED
/OR UNORGANIZED CONVECTION FOR THAT MATTER/ SHOULD TRACK E-SE
WITH TIME AND REMAIN SOUTH OF THE FORECAST AREA THROUGH THE
MORNING HOURS. EVEN MOST OF THE CLOUD DEBRIS SHOULD BE CARRIED
DOWNSTREAM TO THE EAST. THE NAM/GFS/ECMWF ALL SEEM TO BE DEPICTING
A WEAK TROUGH IN WESTERN WI AND LIGHT QPF. THE SOUNDINGS ARE
FAIRLY DRY ON SATURDAY AND THERE ISN`T A CLEAR TRIGGER OUTSIDE OF
PERHAPS A WEAK MID LEVEL WAVE IN IA. THERE IS MODEST ELEVATED
INSTABILITY AND EVEN THE ECMWF DOES HINT AT CONVECTIVE
INITIATION...BUT THE SHOWER/THUNDER CHANCES LOOK BETTER SOUTH AND
EAST OF THE FORECAST AREA. SUNDAY IS PERHAPS A LITTLE MORE
INTERESTING AND SUGGESTS A NEED FOR SLIGHTLY HIGHER POPS AS AN
ADVANCING SURFACE BOUNDARY TRIES TO MAKE IT ACROSS MINNESOTA
DURING THE DAY WITH A SHORTWAVE APPROACHING FROM THE CENTRAL
PLAINS. ALTHOUGH PERHAPS A LITTLE OVERDONE WITH SURFACE
DEWPOINTS...BOTH THE NAM-GFS HAVE LARGE MUCAPE VALUES OF 3000-5000
J/KG IN SOUTHERN MINNESOTA. THE SHEAR PROFILE IS WEAK...WHICH WILL
SUPPRESS THE THREAT FOR SEVERE WEATHER. THERE IS ALSO UNCERTAINTY
AS TO HOW MUCH CONVECTION THERE WILL BE...BUT GIVEN THE LARGE
AMOUNT OF INSTABILITY...PULSE STORMS AND SMALL MULTICELL CLUSTERS
COULD STILL POSE A MARGINAL SEVERE THREAT IF EVERYTHING PANS OUT.
THE BEST CHANCE FOR MORE WIDESPREAD RAIN IN THE AVAILABLE MODEL
GUIDANCE IS MONDAY AFTERNOON INTO EARLY TUESDAY MORNING WITH A
DEVELOPING SURFACE CYCLONE TRACKING OUT OF THE SOUTHERN PLAINS AND
DEEPENING WITH TIME AS IT HEADS TOWARD IA/WI. THERE IS A BIT MORE
CONFIDENCE IN PRECIP AT LEAST ACROSS THE EASTERN PORTIONS OF THE
FORECAST AREA BECAUSE THE GFS/ECMWF SOLUTIONS HAVE SETTLED DOWN
OVER THE PAST 3-4 MODEL CYCLES. PREVIOUS RUNS THIS WEEK WERE ALL
OVER THE PLACE WITH PLACEMENT AND TIMING. OTHERWISE WE`LL REMAIN IN
A FAIRLY INNOCUOUS /AT LEAST COMPARED TO THE HEAVY RAIN PATTERN
WE`VE BEEN IN RECENTLY/ WESTERLY FLOW THROUGH NEXT WEEK WITH NO
BIG SYSTEMS...SEVERE WEATHER OUTBREAKS...BIG TEMPERATURES
SWINGS...ETC.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1211 AM CDT FRI JUN 20 2014
LIFR CONDITIONS DUE TO CIGS HAVE BEGUN TO DEVELOP OVER PORTIONS OF
CENTRAL MN...WITH OTHER AREAS STILL WELL ABOVE VFR THRESHOLDS. AS
MID LEVEL CLOUDS CLEAR ACROSS EASTERN MINNESOTA AND FAR WESTERN
WISCONSIN...THINK STRATUS AND/OR DENSE FOG WILL FORM WITH NEARLY
ALL TAF SITES IFR OR LOWER BY MORNING. RAPID IMPROVEMENT WILL TAKE
PLACE MID MORNING AS TEMPERATURES WARM INTO THE 70S. THEREAFTER...
VFR CONDITIONS EXPECTED.
KMSP...TOUGH CALL FOR MSP AS USUAL FOR FOG DEVELOPMENT AND HOW LOW
VISIBILITIES WILL EVENTUALLY GET. CURRENT TAF CALLS FOR MVFR VIS
WITH TEMPORARY REDUCTIONS OF IFR LEVELS...BUT CONFIDENCE IS NOT
ALL THAT HIGH. AMENDMENTS WILL BE ISSUED OVERNIGHT AS NEEDED.
/OUTLOOK FOR KMSP/
SAT...VFR. MVFR ISO SHRA/TSRA POSSIBLE. WINDS SW 5-10 KTS.
SUN...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS ESE 5 KTS BECMG WNW 5-10KTS.
MON...VFR. WINDS NW 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR MNZ074>077-
082>085-091>093.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...CLF
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
919 PM CDT SAT JUN 21 2014
.UPDATE...
00Z UPPER AIR ANALYSIS INDICATES THE UPPER RIDGE IS SLOWLY WEAKENING
AS H5 HEIGHTS BEGIN TO BREAK DOWN BELOW 590DM AND THE UPPER
RIDGE/SURFACE HIGH SLOWLY BUILDS TO THE SW. H5 FLOW IS SLIGHTLY
STRONGER AND WATER VAPOR/RUC UPPER WIND ANALYSIS INDICATES MORE S/WV
FLOW IN THE REGION. THE CONVECTION FROM TODAY HAS MOSTLY WEAKENED
BUT THERE IS STILL SOME IN THE W/NW IN AREAS WHERE THE UPPER RIDGE
IS WEAKENING. THUS...LEFT SOME SLIGHTLY HIGHER POPS IN THESE AREAS
UNTIL 06Z WHEN HRRR INDICATES ALL STORMS ACROSS THE REGION STORMS
WILL FINALLY DISSIPATE. DUE TO SOME MID/HIGH CLOUD DEBRIS
OVERNIGHT...LOWS WILL BE IN UPPER 60S/LOWER 70S. WENT WITH MAV
GUIDANCE WHICH IS NEAR LAVMOS. NOT EXPECTING ANY PATCHY FOG
OVERNIGHT...OTHER THAN GROUND FOG IN AREAS THAT RECEIVED RAINFALL.
OVERALL...ADJUSTED HOURLY TEMPS/DEWPOINTS/CLOUD COVER ACCORDING TO
CURRENT TRENDS. REST OF THE FORECAST IS ON TRACK. /DC/
&&
.AVIATION...SCATTERED SHRA/TSRA SHOULD DIMINISH BY 06Z...OTHERWISE
EXPECT PATCHY AREAS OF MVFR/IFR CATEGORY FOG AROUND TAF SITES LATE
TONIGHT UNTIL SHORTLY AFTER DAYBREAK SUNDAY. THE LATEST HRRR
SUGGESTS SCT LOW STRATUS WILL BE POSSIBLE ALONG AND SOUTH OF THE
JAN/HKS-MEI CORRIDOR BETWEEN 08-12Z...BUT EXPECT MID/HIGH LEVEL
CLOUDS TO BE MOST PREVALENT. A MOIST AND UNSTABLE AIRMASS WILL
PROMOTE SHRA/TSRA REGENERATION BY NOON SUNDAY OVER MOST OF THE
AREA...PERSISTING INTO EARLY SUNDAY EVENING. /EC/
&&
.PREV DISCUSSION... /ISSUED 152 PM CDT SAT JUN 21 2014/
SHORT TERM...A MORE ACTIVE DAY FOR STORMS IS IN PROGRESS DUE TO
THE LESSENING INFLUENCE OF MID LEVEL HIGH PRESSURE. THIS ACTIVITY
WHILE A LITTLE MORE ORGANIZED THAN FRIDAY IS STILL RATHER SCATTERED
AND WILL POSE ONLY A SMALL SEVERE RISK. THE STORMS SHOULD LAST WELL INTO
THE EVENING AND LIKELY DISSIPATE BY AROUND MIDNIGHT.
AN ACTIVE CONVECTIVE DAY IS EXPECTED ON SUNDAY AS THE RIDGE WILL BE REPLACED
BY A WEAK TROF IN THE MID LEVELS OF THE ATMOSPHERE. THIS SHOULD LEAD
TO MORE WIDESPREAD AND ORGANIZED STORMS FROM LATE MORNING INTO THE
EVENING HOURS. DESPITE THE INCREASED ORGANIZATION...FLOW THROUGHOUT
THE ATMOSPHERE WILL BE WEAK LIMITING THE STRENGTH OF THE STORMS.
LOCALLY HEAVY RAIN WILL BE POSSIBLE DUE TO THE SLOW MOTION AND AROUND
2 INCH PRECIPITABLE WATER VALUES. POPS WILL RANGE FROM HIGH CHANCE TO
LIKELY ON SUNDAY.
EXPECT MONDAY TO BE LESS ACTIVE THAN SUNDAY BUT TO CONTINUE TO
FEATURE SCATTERED AFTERNOON STORMS AS A BROAD MID LEVEL TROF REMAINS
IN PLACE ACROSS THE REGION. /SW/
LONG TERM...TUESDAY THROUGH SATURDAY...IT SHOULD BE A BIT MORE OF AN
ACTIVE WEEK ACROSS THE REGION AS COMPARED TO THIS PAST WEEK. HIGH
PRESSURE WILL NOT BE OCCUPYING OUR WEATHER BUT WE WILL INSTEAD BE
LOCATED UNDER GENERAL TROUGHING WITH SOME DISTURBANCES MOVING ACROSS
THE REGION. THIS WILL BRING GREATER COVERAGE OF CONVECTION THROUGH
THE EARLY TO MIDDLE PORTIONS OF THE WORK WEEK. WITH PW VALUES AROUND
1.9-2 INCHES...HEAVY AND EFFICIENT RAINFALL WILL OCCUR. THERE WILL BE
THE POTENTIAL FOR STRONG TO SEVERE STORMS ALMOST EVERY DAY AS COOL
500MB TEMPS WILL LEAD TO VERTICAL TOTALS AROUND 25-27C AND SBCAPES
WILL BE SUFFICIENT AOA 3000 J/KG...ESPECIALLY IF WE CAN REACH INTO
THE LOWER 90S. TEMPERATURES THROUGH THE PERIOD WILL GENERALLY BE IN
THE LOWER 90S TO START OFF BUT CLOUDS...RAIN AND WET GROUNDS WILL
LIKELY IMPACT HIGHS SLIGHTLY INTO THE MIDDLE/UPPER 80S FOR THE REST
OF THE WEEK. OVERNIGHT LOWS WONT PROVIDE MUCH RELIEF WITH READINGS
EXPECTED TO BE IN THE 70S AND PERHAPS SOME UPPER 60S. /28/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 72 91 71 93 / 17 56 49 45
MERIDIAN 70 91 70 91 / 16 72 69 42
VICKSBURG 70 91 68 93 / 19 45 33 39
HATTIESBURG 72 92 72 91 / 16 56 36 28
NATCHEZ 72 89 70 90 / 17 42 19 18
GREENVILLE 73 92 71 92 / 20 52 37 31
GREENWOOD 72 92 70 91 / 22 60 53 39
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/EC/SW/28
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
613 PM CDT Sat Jun 21 2014
.DISCUSSION...
Issued at 359 PM CDT SAT JUN 21 2014
What else would one expect for the official first day of summer
other than an uncapped tropical airmass defined by high CAPEs and
weak shear with isolated convection along weak boundaries. Very weak
and isolated convection continues to sputter across northern MO this
afternoon in a region of weak h8 convergence. Increasing convection
is noted in a region of moderate h8 moisture convergence which
extends southwest from west central IL cluster into the east central
CWA. HRRR has been picking out this general area for most of today.
Will focus higher PoPs for the late afternoon and early evening
hours this area. A small MCV over south central NE left over from
earlier convection is drifting east towards slightly higher MLCAPEs
around 2000 J/kg. Will insert low chance PoPs for this evening for
nw and north central MO for possible convective development. Last
several runs of the HRRR generates scattered convection this area.
Expect another complex convective scenario tonight. Current
convection over the NE Panhandle may eventually merge with another
nocturnal MCS that rolls off the CO Front Range and heads east. Will
throw in some PoPs over northwest MO towards Sunday morning to cover
the possibility of a dying MCS reaching the CWA.
Continued very warm and humid on Sunday with above average
temperatures. Low confidence on placement of PoPs as any outflow
boundaries left over from tonights convection will play a key role.
Sunday night into Monday still holds the highest PoPs during this
forecast period. While the models have started to diverge on where
another nocturnal MCS will track there is good consensus that a cold
front moving southeast through NE/IA/KS will play a pivotal role.
Have had to lower qpf during this period as confidence on a large
MCS moving through the CWA has diminished. But should see good
coverage of convection with the front. High precipitable water
values are a concern should storms crawl through or back build along
the front. So, later forecasts may need to ramp qpf back up.
While Tuesday looks dry and a tad cooler behind the front weak
embedded disturbances within the quasi-zonal pattern will provide
a lot of uncertainty on timing and location of any convection for
Wednesday/Wednesday night.
The upper pattern evolves for the latter half of the week as an
upper trough pushes through the intermountain region. The backing
flow downstream will enable a southwesterly fetch to spread through
the Central Plains and Mid MO Valley. Should see a slight uptick in
temperatures and humidity with warmer air aloft spreading into the
CWA and forcing any convection to become elevated and more nocturnal.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 612 PM CDT SAT JUN 21 2014
VFR conditions are expected through the entire period. Winds are
expected to be light and generally from the south. Forecast soundings
show a nearly uncapped to uncapped atmosphere by tomorrow afternoon.
Also, a thunderstorm complex may organize over Nebraska and track to
the east affecting NW Missouri around sunrise. This may send another
outflow boundary southward into the area to force storms. All of this
is highly uncertain and at this time coverage looks isolated enough
to preclude a VCTS mention. Instead, have just added a diurnal CU
field and certainty increases with time mention of thunder can be added.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...MJ
AVIATION...CDB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
242 PM CDT FRI JUN 20 2014
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 240 PM CDT FRI JUN 20 2014
THUNDERSTORM COVERAGE/CHANCES REMAIN PRIMARY CONCERN IN SHORT TERM
AS ACTIVE JUNE PATTERN GENERALLY PERSISTS INTO MONDAY.
AFTERNOON SATELLITE IMAGERY SHOWED A CLOSED UPPER LOW PIVOTING
ACROSS SRN SASK CANADA WITH A LOBE EXTENDING SWD ALONG ND/MN
BORDER AT 19Z. THIS LOBE HAS SENT A WEAK BOUNDARY INTO NRN
NEBR...PRIMARILY A DEWPOINT FRONT WITH AROUND 70 DEG SFC DWPTS
FEEDING INTO IT ACROSS NWRN ZONES WITH UPPER 40S JUST TO OUR
NW. ALTHOUGH EARLIER CONVECTION DISPTD...CONTINUED UPSCALE
DEVELOPMENT EXPECTED THROUGH EARLY EVENING AS SPC MESO PAGE
SUGGESTED LITTLE/NO CONVECTIVE INHIBITION WITH 3.5K+ J/KG MLCAPE
SOUTH OF BOUNDARY. WITH 0-6KM BULK SHEAR GENERALLY ON LIGHTER
SIDE...AROUND OR BELOW 30KTS...AFTER INITIAL SVR DEVELOPMENT WITH
HEATING DRIVEN INSTABILITY RELEASE...FEEL BULK OF ACTIVITY COULD
TRANSITION MORE TOWARD A HEAVY RAIN ISSUE AS H85 JET REMAINS
FOCUSED INTO NERN ZONES. UPPED POPS AND QPF ALTHOUGH WENT CLOSER
TO ECMWF QPF AS H85 JET ONLY MODEST AND MOISTURE TRANSPORT LATER
TONIGHT APPEARED TO FOCUS SE OF WHERE BULK OF PRECIP MAY EXIST.
MODEL INDICATIONS ARE THAT PRECIP COULD LINGER SATURDAY MORNING
ACROSS MAINLY WRN IA ZONES...AND POSSIBLY EXTREME NERN
NEBR...BUT BULK OF AREA MUCH OF THE DAY COULD BE DRY. CONTINUED
THIS TREND FROM PRIOR FORECAST BUT RAISED MAX TEMPS...ESPECIALLY
SW...AS AREA SHOULD RECOVER EARLIEST FROM ANY MORNING CLOUDS/ISOLD
TSTMS. LATER IN THE DAY THE FA REMAINS ON SOUTH SIDE OF FASTER
UPPER FLOW WITH FILLING SRN CANADA TROUGH PROVIDES AREA WITH SOME
UPPER DIVERGENCE. HOWEVER...LESS SFC CONVERGENCE WAS NOTED ALONG
A WEAKENED SFC BOUNDARY AND THUS DEVELOPMENT COULD WAIT UNTIL
ANOTHER LOBE ROTATING AROUND UPPER LOW SENDS A STRONGER BOUNDARY
INTO NWRN ZONES LATER SAT NIGHT.
THIS BOUNDARY THEN WEAKENS OR SLOWS AS IT PUSHES INTO FORECAST
SUNDAY...PROBABLY ENOUGH TO WARRANT INCREASING HIGHS SERN ZONES.
MODELS REMAIN FAIRLY CONSISTENT IN SLOWLY SAGGING THE BOUNDARY
ACROSS ZONES SUNDAY/SUNDAY NIGHT AS A STRONGER PIECE OF ENERGY
EJECTS FROM ROCKIES...THUS MODESTLY HIGH POPS WERE MAINTAINED.
THESE HIGH POPS WERE ALSO MAINTAINED FOR MONDAY PERIOD SERN ZONES
DUE TO UNCERTAINTIES IN HOW FAST THIS ENERGY SHIFTS EAST OF THE
FA. COULD SEE SOME REDUCTIONS IN LATER FORECASTS IF FASTER NAM
WOULD VERIFY. COOL ADVECTION/CLOUDS/LINGERING PRECIP ALL INDICATE
COOLER TEMPS SHOULD PREVAIL ON MONDAY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 240 PM CDT FRI JUN 20 2014
12Z GFS/ECMWF SUPPORT A DRY FORECAST MONDAY NGT/TUESDAY MUCH OF
THE FA AS NW FLOW SPREADS OVER THE AREA BEHIND DEPARTING TROUGH.
HOWEVER...TRAILING ENERGY WILL HOLD UP BOUNDARY LATE TUE NIGHT AND
THEN BUILDING UPPER RIDGE WILL LIKELY LIFT IT BACK NORTH. ALTHOUGH
THIS BUILDING RIDGE COULD EVENTUALLY SHUT DOWN OR GREATLY REDUCE
PRECIP THREAT A PERIOD OR TWO...RETURNING BOUNDARY/MOISTURE/INSTABILITY
WILL BRING A RENEWED THREAT IN TUE NGT THROUGH WED NIGHT PERIODS
AND NEXT TROUGH APPROACHING LATE NEXT WEEK WITH LOBES POTENTIALLY
EJECTING OUT PROVIDING ADDITIONAL SUPPORT. THUS SMALL POPS WILL
BLANKET EXTENDED AND WILL ALLOW LATER FORECASTS TO BETTER FINE-
TUNE PARTICULAR PERIODS AS DAYS GET CLOSER.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1244 PM CDT FRI JUN 20 2014
TIMING OF CONVECTION THIS AFTERNOON AND EVENING WILL BE THE MAIN
UNCERTAINTY IN THE FORECAST. EARLIER CONVECTION OVER CENTRAL
NEBRASKA HAS RAPIDLY COLLAPSED SINCE 17Z AND UNSURE OF ANY
SPECIFIC FORCING TO KEY ON THROUGH 00Z. HRRR INDICATES ADDITIONAL
DEVELOPMENT AFTER 20Z SO HAVE FOLLOWED THIS IDEA IN LATEST
FORECAST.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...CHERMOK
LONG TERM...CHERMOK
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
115 PM CDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 114 PM CDT FRI JUN 20 2014
SHOWERS AND THUNDERSTORMS HAVE DIMINISHED TO A FEW
SPRINKLES...HOWEVER THIS IS EXPECTED TO ONLY BE A SHORT TERM.
STALL BOUNDARY CONTINUED TO RESIDE ACROSS THE STATE. EARLY THIS
AFTERNOON EXPECT THE SUN TO COME ON WITH TEMPS TO RISE INTO THE
MID AND UPPER 80S. THIS WILL CAUSE THE CAP TO WEAKEN AND SCT
THUNDERSTORMS ARE EXPECTED TO DEVELOP. DEVELOPMENT IS EXPECT EAST
OF A VTN TO OGA LINE. INSTABILITY INCREASES WITH CAPE VALUES OF A
2K TO 3K J/KG...AND A WEAK WAVE CROSSING THE ROCKIES THIS
AFTERNOON WILL PROVIDE THE NEEDED KICK START TO GET THINGS GOING
AGAIN. EXPECT STORMS TO REDEVELOP AROUND 4 PM CDT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT FRI JUN 20 2014
THE NAM AND RAP SHOW AN AREA OF MIDLEVEL CLOUDS ACROSS ERN COLO THIS
MORNING BECOMING CONVECTIVELY ACTIVE 09Z-12Z THIS MORNING. THE
DISTURBANCE SHOULD MOVE EAST THRU SRN NEB THIS AM PRODUCING A
CLUSTER OF ELEVATED TSTMS. THE RAP INDICATES 750MB CAPE OF AROUND
1000 J/KG SUGGESTING THE POTENTIAL FOR SOME HAIL. THIS ACTIVITY
DISSIPATES LATE THIS MORNING TO BE FOLLOWED BY A SECOND AREA OF TSTM
DEVELOPMENT FROM ROUGHLY KIML NORTHEAST THROUGH KONL THIS AFTN WITH
THE BETTER RAIN CHANCES FROM HAYES CENTER NORTHEAST THROUGH KONL.
BUFKIT SUGGESTS A WEAK MULTICELL ENVIRONMENT GIVEN THE WEAK SHEAR
AROUND 25 KT. MLCAPE THOUGH AROUND 3000 J/KG IN THE RAP MODEL
SUGGESTS SOME STRONG UPDRAFTS DEVELOPING THIS AFTN NEAR OR SOUTH OF
KOGA AND KLBF. SO SEVERE WEATHER CHANCES CONTINUE ALTHOUGH THE
POTENTIAL FOR LONGER LIVED STORMS WOULD APPEAR LOW.
STORMS WILL LIKELY FIRE FROM SOUTHWEST NEB TO NCNTL NEB THIS
AFTERNOON AND THIS EVENING AND COALESCE INTO CLUSTERS WHICH MOVE OFF
EAST OF THE FCST AREA AROUND 06Z. POPS ARE LIMITED TO 40 PERCENT
GIVEN THE WEAKNESS IN THE WINDS ALOFT AND LOW QPF GENERATED BY THE
MODELS.
HIGHS TODAY RISE INTO THE 80S AND LOWS TONIGHT FALL INTO THE 50S TO
LOWER 60S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI JUN 20 2014
MOIST...WARM AND UNSTABLE CONDITIONS WILL CONTINUE ACROSS ALL OF
WESTERN AND NORTH CENTRAL NEBRASKA SATURDAY. MODELS ALL AGREE THAT
A WARM FRONT WILL BE LOCATED IN AN EAST TO WEST FASHION...BUT
DISAGREE ON THE LOCATION. REGARDLESS...IT APPEARS THAT SCATTERED
TSTMS WILL INITIATE ACROSS THE HIGH PLAINS IN MOIST UPSLOPE
REGIME. THESE WILL LIKELY BEGIN AS SUPERCELLS WITH BULK SHEAR NEAR
40 KTS. BUFKIT DATA FROM VARIOUS LOCATIONS ACROSS THE PLAINS
SUGGESTS RIGHT TURNING SUPERCELLS THE DOMINATE STORM MODE AT
FIRST...THEN CONGEAL INTO ONE OR MORE CLUSTERS SATURDAY NIGHT AS
SOUTHERLY LOW LEVEL JET INCREASES. THE WARM FRONT LOCATION WILL
HAVE TO BE MONITORED...AS WINDS WILL BE BACKED MORE TO THE EAST ON
THE NORTH SIDE OF THE BOUNDARY...WHICH WILL ENHANCE LOW LEVEL SHEAR
AND POSSIBLE TORNADO DEVELOPMENT.
SUNDAY A SHORTWAVE DISTURBANCE WILL TRACK ACROSS THE NORTHERN
ROCKIES AND TOWARD THE NORTHERN PLAINS. A SURFACE LOW WILL DEEPEN
ACROSS EASTERN COLORADO IN RESPONSE...WITH MOIST EAST TO NORTHEAST
WINDS ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA TO THE
NORTH OF THE LOW. STORM DEVELOPMENT WILL BE AIDED BY THE SHORTWAVE
DISTURBANCE ACROSS THE PANHANDLE SUNDAY AFTERNOON...WITH STORMS
LIKELY MERGING INTO AN MCS AS THEY TRACK EAST SOUTHEAST ACROSS
NEBRASKA SUNDAY EVENING. LOCALLY HEAVY RAIN COULD MATERIALIZE AND
POTENTIAL WILL HAVE TO BE MONITORED.
MONDAY INTO TUESDAY...SOMEWHAT COOLER AND DRIER BEHIND THE
SHORTWAVE DISTURBANCE. BY MIDWEEK...RICH GULF MOISTURE RETURNS.
MODELS INDICATING DEW POINTS IN THE UPPER 60S TO NEAR 70 FOR MUCH
OF THE FORECAST AREA BY WEEKS END. THATS WHEN TSTM CHANCES MAY
INCREASE ONCE AGAIN...AS UPPER LEVEL TROUGHING DEVELOPS INTO THE
PACIFIC NORTHWEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 114 PM CDT FRI JUN 20 2014
SHOWERS WILL EXIT THE KLBF AREA OVER THE NEXT HOUR...WITH THE SUN
COMING OUT. AFTER A BRIEF BREAK IN ACTIVITY...STORMS ARE EXPECTED
TO REDEVELOP LATER THIS AFTERNOON INTO THE EVENING HOURS ACROSS
SOUTHWEST INTO N CENTRAL NEB. ACTIVITY HAS THE CHANCE TO IMPACT
KLBF...ALTHOUGH LESS CONFIDENCE IN ACTIVITY TO IMPACT KVTN. DID
INCLUDE A SOME TS IN THE KLBF TAF...HOWEVER WATCH FOR AMENDMENTS
AS TIMING MAY BE OFF OR NEEDED TO BE EXTEND. ACTIVITY WILL LIFT
TO THE NORTHEAST OVERNIGHT WITH SKIES CLEARING FROM THE WEST.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MASEK
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1253 PM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 327 AM CDT FRI JUN 20 2014
EARLY MORNING WATER VAPOR IMAGERY INDICATES THAT THE PERSISTENT
UPPER LEVEL LOW IS SLOWLY MOVING INTO SRN SASK AS A STRONG
SHORTWAVE TROUGH ROTATES THROUGH THE BASE OF THE TROUGH OVER
NORTHERN MN. UPSTREAM OVER THE ROCKIES ZONAL FLOW AS DEVELOPING
WITH HEIGHT RISES OF 50 TO 90 M AT H5 NOTED. THE NEXT SYSTEM
IDENTIFIABLE SHORTWAVE TROUGH ON THE 00Z UPPER AIR ANALYSIS WAS
MOVING INTO NRN CA. THE DEVELOPING ZONAL FLOW WAS LEADING TO LEE
TROUGHING OVER THE HIGH PLAINS EARLY THIS MORNING AND THE WINDS
ACROSS CNTRL AND WRN NEB HAVE BECOME SOUTHEAST. AS THE HEIGHT
RISES MOVE INTO THE PLAINS TODAY THE LOW- TO MID-LEVEL WAA WILL
INCREASE THROUGH THE DAY ALLOWING FOR THE AREA OF +15 C H85 DEW
POINTS FROM ERN KS INTO THE TX PANHANDLE TO MOVE NWD INTO CNTRL
NEB. LAPSE RATES WILL BE STEEPENING ALOFT...BUT POINT FORECAST
SOUNDINGS INDICATE LITTLE IN THE WAY OF AN EML OR CAPPING
INVERSION DEVELOPING TODAY. THUS AS THIS MOISTURE RETURNS INTO AN
UPCAPPED ATMOSPHERE CHARACTERIZED BY AROUND 1500-2000 J/KG OF
MLCAPE ISO TO SCT TSRA WILL LIKELY DEVELOP BY LATE AFTERNOON OVER
THE NW CWA CLOSEST TO THE AREA OF STRONGEST WAA AND A WEAK SFC
TROUGH. OPERATIONAL MODELS APPEAR OVERDONE WITH QPF GIVEN THE
HEIGHT RISES EXPECTED THROUGH THE DAY. NEVERTHELESS CHC POPS STILL
APPEAR WARRANTED OVER THE CNTRL AND NRN CWA. SOME OF THESE WILL
LIKELY CONT INTO THE OVERNIGHT HOURS BUT THE LACK OF A STRONGER
LOW-LEVEL JET AND MARGINAL MOISTURE/INSTABILITY WE THINK MUCH OF
THE ACTIVITY MAY TEND TO DIMINISH DURING THE LATE EVENING.
MOST OF THE DAY ON SAT SHOULD BE DRY ACRS THE FA BUT MOISTURE
RETURN WILL CONT...AND WITH MID-LEVEL LAPSE RATES
INCREASING...GREATER INSTABILITY WILL LIKELY DEVELOP ACROSS THE
FA. AT THE MOMENT IT APPEARS THAT THE MOST LIKELY SCENARIO IS FOR
THUNDERSTORMS TO DEVELOP ALONG THE SURFACE TROUGH OVER SOUTHERN SD
INTO WRN NEB AND ROLL EAST SAT NIGHT THRU THE CWA. THE CONFIDENCE
IN THE FORECAST DECREASES BY SUNDAY WITH MODEL DISAGREEMENT
INCREASING AND THE EFFECTS OF A COUPLE OF DAYS OF SCT CONVECTION
UNKNOWN. THOUGH MODELS CONT TO ADVERTISE STRONGER FORCING FOR
ASCENT MOVING INTO THE HIGH PLAINS BY SUN. SOME STORMS CAN`T BE
RULED OUT DURING THE DAY ON SUNDAY...BUT MOST OF THE FOCUS MAY
STILL BE WEST OF OUR CWA DURING THE DAY CLOSER TO THE LARGE-SCALE
ASCENT.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 327 AM CDT FRI JUN 20 2014
WE WILL CONT WITH THE LIKELY POPS ON SUNDAY NIGHT INTO MON
MORNING AS THE PREVIOUSLY MENTIONED FORCING MOVES ACROSS THE CNTRL
PLAINS WITH THE PATTERN FAVORABLE FOR AN MCS TO MOVE EAST ACROSS
THE AREA...ESPECIALLY IN THE SRN CWA INTO MON MORNING. THE GLOBAL
MODELS ARE THEN STILL IN DECENT AGREEMENT IN THE SUN NIGHT
SHORTWAVE TO CARVE OUT A PROGRESSIVE TROUGH IN THE GREAT LAKES AND
ALLOW FOR NORTHWEST FLOW OVER THE CNTRL/NRN PLAINS. THIS SHOULD
ALLOW THE FOCUS FOR CONVECTION TO SHIFT WEST TO THE HIGH PLAINS
AND WE FEEL THAT THE PERIOD TUE-THU WILL BE DRY OVER THE FA.
TEMPERATURES SHOULD GENERALLY BE SEASONABLE THROUGH THE PERIOD.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1244 PM CDT FRI JUN 20 2014
TIMING OF CONVECTION THIS AFTERNOON AND EVENING WILL BE THE MAIN
UNCERTAINTY IN THE FORECAST. EARLIER CONVECTION OVER CENTRAL
NEBRASKA HAS RAPIDLY COLLAPSED SINCE 17Z AND UNSURE OF ANY
SPECIFIC FORCING TO KEY ON THROUGH 00Z. HRRR INDICATES ADDITIONAL
DEVELOPMENT AFTER 20Z SO HAVE FOLLOWED THIS IDEA IN LATEST
FORECAST.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOUSTEAD
LONG TERM...BOUSTEAD
AVIATION...FOBERT
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
620 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT FRI JUN 20 2014
THE NAM AND RAP SHOW AN AREA OF MIDLEVEL CLOUDS ACROSS ERN COLO THIS
MORNING BECOMING CONVECTIVELY ACTIVE 09Z-12Z THIS MORNING. THE
DISTURBANCE SHOULD MOVE EAST THRU SRN NEB THIS AM PRODUCING A
CLUSTER OF ELEVATED TSTMS. THE RAP INDICATES 750MB CAPE OF AROUND
1000 J/KG SUGGESTING THE POTENTIAL FOR SOME HAIL. THIS ACTIVITY
DISSIPATES LATE THIS MORNING TO BE FOLLOWED BY A SECOND AREA OF TSTM
DEVELOPMENT FROM ROUGHLY KIML NORTHEAST THROUGH KONL THIS AFTN WITH
THE BETTER RAIN CHANCES FROM HAYES CENTER NORTHEAST THROUGH KONL.
BUFKIT SUGGESTS A WEAK MULTICELL ENVIRONMENT GIVEN THE WEAK SHEAR
AROUND 25 KT. MLCAPE THOUGH AROUND 3000 J/KG IN THE RAP MODEL
SUGGESTS SOME STRONG UPDRAFTS DEVELOPING THIS AFTN NEAR OR SOUTH OF
KOGA AND KLBF. SO SEVERE WEATHER CHANCES CONTINUE ALTHOUGH THE
POTENTIAL FOR LONGER LIVED STORMS WOULD APPEAR LOW.
STORMS WILL LIKELY FIRE FROM SOUTHWEST NEB TO NCNTL NEB THIS
AFTERNOON AND THIS EVENING AND COALESCE INTO CLUSTERS WHICH MOVE OFF
EAST OF THE FCST AREA AROUND 06Z. POPS ARE LIMITED TO 40 PERCENT
GIVEN THE WEAKNESS IN THE WINDS ALOFT AND LOW QPF GENERATED BY THE
MODELS.
HIGHS TODAY RISE INTO THE 80S AND LOWS TONIGHT FALL INTO THE 50S TO
LOWER 60S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI JUN 20 2014
MOIST...WARM AND UNSTABLE CONDITIONS WILL CONTINUE ACROSS ALL OF
WESTERN AND NORTH CENTRAL NEBRASKA SATURDAY. MODELS ALL AGREE THAT
A WARM FRONT WILL BE LOCATED IN AN EAST TO WEST FASHION...BUT
DISAGREE ON THE LOCATION. REGARDLESS...IT APPEARS THAT SCATTERED
TSTMS WILL INITIATE ACROSS THE HIGH PLAINS IN MOIST UPSLOPE
REGIME. THESE WILL LIKELY BEGIN AS SUPERCELLS WITH BULK SHEAR NEAR
40 KTS. BUFKIT DATA FROM VARIOUS LOCATIONS ACROSS THE PLAINS
SUGGESTS RIGHT TURNING SUPERCELLS THE DOMINATE STORM MODE AT
FIRST...THEN CONGEAL INTO ONE OR MORE CLUSTERS SATURDAY NIGHT AS
SOUTHERLY LOW LEVEL JET INCREASES. THE WARM FRONT LOCATION WILL
HAVE TO BE MONITORED...AS WINDS WILL BE BACKED MORE TO THE EAST ON
THE NORTH SIDE OF THE BOUNDARY...WHICH WILL ENHANCE LOW LEVEL SHEAR
AND POSSIBLE TORNADO DEVELOPMENT.
SUNDAY A SHORTWAVE DISTURBANCE WILL TRACK ACROSS THE NORTHERN
ROCKIES AND TOWARD THE NORTHERN PLAINS. A SURFACE LOW WILL DEEPEN
ACROSS EASTERN COLORADO IN RESPONSE...WITH MOIST EAST TO NORTHEAST
WINDS ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA TO THE
NORTH OF THE LOW. STORM DEVELOPMENT WILL BE AIDED BY THE SHORTWAVE
DISTURBANCE ACROSS THE PANHANDLE SUNDAY AFTERNOON...WITH STORMS
LIKELY MERGING INTO AN MCS AS THEY TRACK EAST SOUTHEAST ACROSS
NEBRASKA SUNDAY EVENING. LOCALLY HEAVY RAIN COULD MATERIALIZE AND
POTENTIAL WILL HAVE TO BE MONITORED.
MONDAY INTO TUESDAY...SOMEWHAT COOLER AND DRIER BEHIND THE
SHORTWAVE DISTURBANCE. BY MIDWEEK...RICH GULF MOISTURE RETURNS.
MODELS INDICATING DEW POINTS IN THE UPPER 60S TO NEAR 70 FOR MUCH
OF THE FORECAST AREA BY WEEKS END. THATS WHEN TSTM CHANCES MAY
INCREASE ONCE AGAIN...AS UPPER LEVEL TROUGHING DEVELOPS INTO THE
PACIFIC NORTHWEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 616 AM CDT FRI JUN 20 2014
ISOLATED STORMS ACROSS SWRN NEB THIS MORNING COULD AFFECT KLBF IF
THEY CONTINUE MOVING NORTHEAST AS RADAR AND THE RAP MODEL
INDICATE. SCATTERED TSRA ARE EXPECTED THIS AFTN FROM KIML-KTIF-
KONL AND AREAS EAST. VFR IS EXPECTED ELSEWHERE. THESE STORMS SHOULD
EXIT THE FCST AREA TO EAST AROUND 06Z TONIGHT. VFR IS EXPECTED ALL
AREAS THEREAFTER.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
347 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT FRI JUN 20 2014
THE NAM AND RAP SHOW AN AREA OF MIDLEVEL CLOUDS ACROSS ERN COLO THIS
MORNING BECOMING CONVECTIVELY ACTIVE 09Z-12Z THIS MORNING. THE
DISTURBANCE SHOULD MOVE EAST THRU SRN NEB THIS AM PRODUCING A
CLUSTER OF ELEVATED TSTMS. THE RAP INDICATES 750MB CAPE OF AROUND
1000 J/KG SUGGESTING THE POTENTIAL FOR SOME HAIL. THIS ACTIVITY
DISSIPATES LATE THIS MORNING TO BE FOLLOWED BY A SECOND AREA OF TSTM
DEVELOPMENT FROM ROUGHLY KIML NORTHEAST THROUGH KONL THIS AFTN WITH
THE BETTER RAIN CHANCES FROM HAYES CENTER NORTHEAST THROUGH KONL.
BUFKIT SUGGESTS A WEAK MULTICELL ENVIRONMENT GIVEN THE WEAK SHEAR
AROUND 25 KT. MLCAPE THOUGH AROUND 3000 J/KG IN THE RAP MODEL
SUGGESTS SOME STRONG UPDRAFTS DEVELOPING THIS AFTN NEAR OR SOUTH OF
KOGA AND KLBF. SO SEVERE WEATHER CHANCES CONTINUE ALTHOUGH THE
POTENTIAL FOR LONGER LIVED STORMS WOULD APPEAR LOW.
STORMS WILL LIKELY FIRE FROM SOUTHWEST NEB TO NCNTL NEB THIS
AFTERNOON AND THIS EVENING AND COALESCE INTO CLUSTERS WHICH MOVE OFF
EAST OF THE FCST AREA AROUND 06Z. POPS ARE LIMITED TO 40 PERCENT
GIVEN THE WEAKNESS IN THE WINDS ALOFT AND LOW QPF GENERATED BY THE
MODELS.
HIGHS TODAY RISE INTO THE 80S AND LOWS TONIGHT FALL INTO THE 50S TO
LOWER 60S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI JUN 20 2014
MOIST...WARM AND UNSTABLE CONDITIONS WILL CONTINUE ACROSS ALL OF
WESTERN AND NORTH CENTRAL NEBRASKA SATURDAY. MODELS ALL AGREE THAT
A WARM FRONT WILL BE LOCATED IN AN EAST TO WEST FASHION...BUT
DISAGREE ON THE LOCATION. REGARDLESS...IT APPEARS THAT SCATTERED
TSTMS WILL INITIATE ACROSS THE HIGH PLAINS IN MOIST UPSLOPE
REGIME. THESE WILL LIKELY BEGIN AS SUPERCELLS WITH BULK SHEAR NEAR
40 KTS. BUFKIT DATA FROM VARIOUS LOCATIONS ACROSS THE PLAINS
SUGGESTS RIGHT TURNING SUPERCELLS THE DOMINATE STORM MODE AT
FIRST...THEN CONGEAL INTO ONE OR MORE CLUSTERS SATURDAY NIGHT AS
SOUTHERLY LOW LEVEL JET INCREASES. THE WARM FRONT LOCATION WILL
HAVE TO BE MONITORED...AS WINDS WILL BE BACKED MORE TO THE EAST ON
THE NORTH SIDE OF THE BOUNDARY...WHICH WILL ENHANCE LOW LEVEL SHEAR
AND POSSIBLE TORNADO DEVELOPMENT.
SUNDAY A SHORTWAVE DISTURBANCE WILL TRACK ACROSS THE NORTHERN
ROCKIES AND TOWARD THE NORTHERN PLAINS. A SURFACE LOW WILL DEEPEN
ACROSS EASTERN COLORADO IN RESPONSE...WITH MOIST EAST TO NORTHEAST
WINDS ACROSS MOST OF WESTERN AND NORTH CENTRAL NEBRASKA TO THE
NORTH OF THE LOW. STORM DEVELOPMENT WILL BE AIDED BY THE SHORTWAVE
DISTURBANCE ACROSS THE PANHANDLE SUNDAY AFTERNOON...WITH STORMS
LIKELY MERGING INTO AN MCS AS THEY TRACK EAST SOUTHEAST ACROSS
NEBRASKA SUNDAY EVENING. LOCALLY HEAVY RAIN COULD MATERIALIZE AND
POTENTIAL WILL HAVE TO BE MONITORED.
MONDAY INTO TUESDAY...SOMEWHAT COOLER AND DRIER BEHIND THE
SHORTWAVE DISTURBANCE. BY MIDWEEK...RICH GULF MOISTURE RETURNS.
MODELS INDICATING DEW POINTS IN THE UPPER 60S TO NEAR 70 FOR MUCH
OF THE FORECAST AREA BY WEEKS END. THATS WHEN TSTM CHANCES MAY
INCREASE ONCE AGAIN...AS UPPER LEVEL TROUGHING DEVELOPS INTO THE
PACIFIC NORTHWEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1227 AM CDT FRI JUN 20 2014
THE RAP AND NAM MODELS SHOW A CLUSTER OF TSTMS DEVELOPING ACROSS
SWRN NEB AROUND 10Z. THESE STORMS SHOULD MOVE OFF TO THE EAST 12Z-
15Z AND REMAIN SOUTH OF INTERSTATE 80.
WITH CLEAR SKY AND RESIDUAL MOISTURE FROM THE HEAVY RAINS LAST
NIGHT...LOCALIZED FOG IS A FORECAST CONCERN FOR CENTRAL AND
SOUTHWEST NEBRASKA INCLUDING BBW...LBF AND OGA. CURRENT WIND IN THE
PLATTE RIVER VALLEY IS 140-160 AT 4-6KT WHICH COULD SUPPORT A
FORECAST FOR FOG AT LBF IF IT DECREASES TO 4KT OR LOWER AND ALSO
NORTHWEST AND SOUTHEAST OF LBF. SURFACE DEWPOINTS UPWIND OF LBF ARE
IN THE UPPER 50S. HOWEVER...THE DEPTH OF THE MOISTURE JUST OFF THE
SURFACE IS LIKELY TO BE INSUFFICIENT FOR CREATING A SATURATED LAYER
IN THE LOWEST 1000 FEET ABOVE THE SURFACE AND WIDESPREAD FG/BR.
STILL...IN A FAIRLY NARROW BBW-LBF-OGA SWATH...VERY HEAVY RAIN FROM
STORMS LAST NIGHT MAY HAVE LEFT ENOUGH STANDING SURFACE WATER TO
SATURATE THE COOL NEAR-SURFACE LAYER IN PLACES AND MAY PRODUCE
SPOTTY MIST OR FOG. WHEREVER MIST/FOG MAY DEVELOP...THE VISIBILITY
MAY BE REDUCED TO 1SM OR LOWER. CONFIDENCE IS NOT HIGH ENOUGH TO
INCLUDE BR/FG IN THE TERMINAL FORECAST FOR LBF. IN THE REST OF THE
AREA...CEILING AND VISIBILITY IS LIKELY TO BE UNLIMITED.
THUNDERSTORMS ARE POSSIBLE FRIDAY AFTERNOON AND EVENING SOUTH AND
EAST OF AN ONL-OGA LINE. THAT LINE MARKS A CONTRAST BETWEEN MOIST
UNSTABLE AIR IN THE SOUTH AND DRY AIR TO THE NORTH. HOWEVER...THE
THUNDERSTORM COVERAGE IS LIKELY TO BE LIMITED TO 30 PERCENT OR LESS.
THAT RESULTS IN A LOW PROBABILITY OF A THUNDERSTORM AT ANY
PARTICULAR SITE.
WIND ON FRIDAY IS EXPECTED TO BE 260-290 AT 12-14G21-22KT IN
NORTHERN NEBRASKA BY 17Z. AIRPORTS THAT ARE LIKELY TO BE AFFECTED
INCLUDE ONL...ANW...VTN...TIF AND MHN. WIND IN THE REST OF THE AREA
WILL BE 170-210 AT LESS THAN 12KT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1229 AM CDT FRI JUN 20 2014
.SYNOPSIS...
ISSUED AT 350 PM CDT THU JUN 19 2014
UPPER CLOSED LOW OVER MONTANA SHEARING INTO SOUTHERN CANADA THIS
AFTERNOON. UPPER RIDGE THROUGH HUDSON BAY.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 350 PM CDT THU JUN 19 2014
PRIMARY CONCERN FOR THIS PORTION OF THE FORECAST IS ON LOW
TEMPERATURES TONIGHT AND SHOWER AND THUNDERSTORM CHANCES ON FRIDAY.
AT 19Z WATER VAPOR IMAGERY SHOWED THE UPPER LEVEL LOW CENTERED OVER
SOUTHWEST SASKATCHEWAN WITH A STRONG SHORTWAVE TROUGH MOVING
NORTHEAST ACROSS WESTERN SOUTH DAKOTA. THERE WAS A GOOD FETCH OF DRY
AIR PULLING UP INTO THE SYSTEM...WHICH WAS SEEN OVER NEBRASKA. THIS
DRY AIR WAS SEEN ON VISIBLE SATELLITE...WHERE SUNNY SKIES WERE
OBSERVED OVER MUCH OF THE STATE. SURFACE ANALYSIS SHOWED THE COLD
FRONT FROM CENTRAL NORTH DAKOTA THROUGH WESTERN IOWA...ACROSS
SOUTHEAST NEBRASKA AND INTO CENTRAL KANSAS. HIGH PRESSURE WAS
CENTERED OVER SOUTHWEST NEBRASKA AND NORTHWEST KANSAS. THE AIRMASS
DIFFERENCES WERE QUITE APPARENT WITH DEWPOINTS AHEAD OF THE FRONT IN
THE UPPER 60S AND 70S...WITH DEWPOINTS BEHIND THE FRONT MOSTLY IN
THE 30S-50S. TEMPERATURES WERE COOLER AS WELL...WITH TEMPERATURES AT
MID AFTERNOON IN THE 70S AND LOW 80S.
THE UPPER LEVEL LOW WILL MIGRATE EAST ALONG THE CANADA BORDER
THROUGH THE DAY FRIDAY...WITH THE MODELS IN DECENT AGREEMENT WITH IT
LIFTING SLIGHTLY NORTH BY THE END OF THE DAY...CENTERED OVER
SOUTHERN MANITOBA.
WITH PLENTIFUL DRY AIR IN PLACE TONIGHT...CLEAR SKIES WILL BE SEEN
ACROSS THE REGION. WINDS WILL DROP OFF AND WITH THE COOLER AIRMASS
IN PLACE LOOKING FOR LOWS FROM THE LOW 50S TO THE LOW 60S. FOR
FRIDAY THE 12Z AND 18Z MODEL RUNS ARE NOW INDICATING A VERY SUBTLE
SHORTWAVE WILL MOVE ACROSS SOUTHERN NEBRASKA AND KANSAS DURING THE
DAY FRIDAY. WARM AIR ADVECTION WILL OCCUR DURING THE DAY ALONG WITH
MOISTURE RETURN IN THE LOW LEVELS AS A SURFACE LOW DEVELOPS OVER
EASTERN COLORADO. IT APPEARS THAT THERE WILL BE AN INVERTED TROUGH
FROM THAT SURFACE LOW THROUGH NORTH CENTRAL NEBRASKA. THIS ADDED
MOISTURE SHOULD HELP CONVECTION DEVELOP ALONG AND EAST OF THE
BOUNDARY IN THE AFTERNOON AS THE SHORTWAVE ENERGY PASSES. GOOD
INSTABILITY IS BEING INDICATED BY THE MODELS IN THESE AREAS...WITH
SB CAPE UP TO 3500 J/KG IN SOME AREAS AT THE TIME OF PEAK HEATING.
DEEP LAYER WIND SHEAR ISN/T OVERLY STRONG...BUT 30 TO 35KTS WITH THE
AMOUNT OF INSTABILITY INDICATED SHOULD BE SUFFICIENT FOR AT LEAST A
FEW STRONG STORMS. THE BEST CHANCES FOR STORMS LOOKS TO BE EAST OF A
LINE FROM OGALLALA TO AINSWORTH.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 350 PM CDT THU JUN 19 2014
CLOSED LOW OVER SOUTHWEST CANADA WILL CONTINUE TO AFFECT WEATHER
OVER NORTHERN PLAINS THE NEXT SEVERAL DAYS. MODELS IN FAIR
AGREEMENT. UPPER LOW WILL MOVE JUST NORTH OF NORTH DAKOTA FRIDAY
WITH MAINLY ZONAL UPPER PATTERN OVER THE NORTHERN PLAINS. SURFACE
TROUGH ALONG THE FRONT RANGE WILL MOVE INTO WESTERN NEBRASKA FRIDAY
NIGHT AND WILL BE THE FOCUS FOR ONGOING THUNDERSTORMS THROUGH THE
EARLY EVENING MAINLY EAST OF HIGHWAY 83. MID LEVEL WAVE MOVING
THROUGH MEAN FLOW AND LOW LEVEL JET WILL KEEP THUNDERSTORMS MOVING
EAST OVER NIGHT. HAVE LEFT FORECAST DRY SATURDAY MORNING WITH
INCREASING CHANCES SATURDAY AFTERNOON ALONG THE SURFACE TROUGH AND
THEN WITH THE COOL FRONTAL PASSAGE OVER NIGHT WITH CHANCE POPS RETAINED.
GULF OPEN SATURDAY NIGHT INTO SUNDAY AS COOLER AIR MOVES IN FROM
THE NORTHWEST. VERY STRONG MID LEVEL WAVE TO MOVE ACROSS WESTERN
NEBRASKA SUNDAY NIGHT AS UPPER LOW OVER SOUTH CENTRAL CANADA
PUSHES SLOWLY SOUTH ACROSS THE NORTHERN PLAINS. HAVE UPPED TO
LIKELY`S SUNDAY NIGHT AND INCREASED QPF. COOLER TEMPERATURES
THROUGH THE FIRST PART OF THE WEEK. UPPER TROUGH WILL CONTINUE TO
MOVE TO THE SOUTHEAST ACROSS THE NORTHERN PLAINS INTO IOWA AND
BRING COOLER TEMPERATURES TO THE FORECAST AREA AND ON AND OFF
AGAIN SHOWERS AND THUNDERSTORMS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1227 AM CDT FRI JUN 20 2014
THE RAP AND NAM MODELS SHOW A CLUSTER OF TSTMS DEVELOPING ACROSS
SWRN NEB AROUND 10Z. THESE STORMS SHOULD MOVE OFF TO THE EAST 12Z-
15Z AND REMAIN SOUTH OF INTERSTATE 80.
WITH CLEAR SKY AND RESIDUAL MOISTURE FROM THE HEAVY RAINS LAST
NIGHT...LOCALIZED FOG IS A FORECAST CONCERN FOR CENTRAL AND
SOUTHWEST NEBRASKA INCLUDING BBW...LBF AND OGA. CURRENT WIND IN THE
PLATTE RIVER VALLEY IS 140-160 AT 4-6KT WHICH COULD SUPPORT A
FORECAST FOR FOG AT LBF IF IT DECREASES TO 4KT OR LOWER AND ALSO
NORTHWEST AND SOUTHEAST OF LBF. SURFACE DEWPOINTS UPWIND OF LBF ARE
IN THE UPPER 50S. HOWEVER...THE DEPTH OF THE MOISTURE JUST OFF THE
SURFACE IS LIKELY TO BE INSUFFICIENT FOR CREATING A SATURATED LAYER
IN THE LOWEST 1000 FEET ABOVE THE SURFACE AND WIDESPREAD FG/BR.
STILL...IN A FAIRLY NARROW BBW-LBF-OGA SWATH...VERY HEAVY RAIN FROM
STORMS LAST NIGHT MAY HAVE LEFT ENOUGH STANDING SURFACE WATER TO
SATURATE THE COOL NEAR-SURFACE LAYER IN PLACES AND MAY PRODUCE
SPOTTY MIST OR FOG. WHEREVER MIST/FOG MAY DEVELOP...THE VISIBILITY
MAY BE REDUCED TO 1SM OR LOWER. CONFIDENCE IS NOT HIGH ENOUGH TO
INCLUDE BR/FG IN THE TERMINAL FORECAST FOR LBF. IN THE REST OF THE
AREA...CEILING AND VISIBILITY IS LIKELY TO BE UNLIMITED.
THUNDERSTORMS ARE POSSIBLE FRIDAY AFTERNOON AND EVENING SOUTH AND
EAST OF AN ONL-OGA LINE. THAT LINE MARKS A CONTRAST BETWEEN MOIST
UNSTABLE AIR IN THE SOUTH AND DRY AIR TO THE NORTH. HOWEVER...THE
THUNDERSTORM COVERAGE IS LIKELY TO BE LIMITED TO 30 PERCENT OR LESS.
THAT RESULTS IN A LOW PROBABILITY OF A THUNDERSTORM AT ANY
PARTICULAR SITE.
WIND ON FRIDAY IS EXPECTED TO BE 260-290 AT 12-14G21-22KT IN
NORTHERN NEBRASKA BY 17Z. AIRPORTS THAT ARE LIKELY TO BE AFFECTED
INCLUDE ONL...ANW...VTN...TIF AND MHN. WIND IN THE REST OF THE AREA
WILL BE 170-210 AT LESS THAN 12KT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...POWER
SHORT TERM...BROOKS
LONG TERM...POWER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
920 PM EDT SAT JUN 21 2014
.SYNOPSIS..A SURFACE FRONT WILL PUSH SOUTHEAST THROUGH CENTRAL NORTH
CAROLINA TONIGHT. WEAK HIGH PRESSURE WILL EXTEND OVER THE AREA
THROUGH EARLY MONDAY. A SURFACE TROUGH OF LOW PRESSURE RETURNS
TUESDAY THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM SATURDAY...
A BUSY AFTERNOON AND EVENING WITH MULTIPLE CLUSTERS OF MULTICELLULAR
CONVECTION... MUCH OF IT QUITE STRONG BUT GENERALLY JUST BELOW
SEVERE LIMITS. THE LATEST SURFACE ANALYSIS SHOWS A SURFACE LOW OVER
CENTRAL NC WITH A WEAK CONVERGENCE ZONE RUNNING TO ITS EAST AND
WEST... WHILE A MORE SUBSTANTIAL BACKDOOR FRONT EXTENDS THROUGH
CENTRAL VA. A VERY WARM/MOIST (PW 1.5-2.0 IN.) AND UNSTABLE AIR
MASS PERSISTS OVER NC WITH MLCAPE STILL AT 1500-2000 J/KG...
ALTHOUGH CINH HAS GROWN QUICKLY IN RECENT HOURS... AND LOW LEVEL
LAPSE RATES HAVE LOWERED IN PART BY THE NUMEROUS STORMS AND MULTIPLE
OUTFLOWS. SEVERAL OF THE STORMS NEAR THE WEAK CONVERGENCE ZONE
EXHIBITED WEAK BUT DEEP ROTATION EARLIER THIS EVENING AS THEY FED ON
THIS VORTICITY... HOWEVER THIS TOO HAS WANED. THE RECENT RAP MODEL
RUN SHOWS STEADY MID LEVEL DRYING OVERNIGHT ESPECIALLY IN THE NW CWA
WITH PW FALLING NEAR 1.2 IN... ALTHOUGH VALUES HOLD UP IN THE ERN/SE
CWA WITH CONTINUED TALL SKINNY MARGINAL CAPE AND WEAK MBE MOVEMENT
EXPECTED. SO EVEN AFTER THE NUMEROUS STORMS IN THE COASTAL PLAIN
SHIFT SLOWLY EAST OUT OF THE CWA SOON AFTER MIDNIGHT... ADDITIONAL
ISOLATED STORMS OR STORM CLUSTERS FROM THE TRIANGLE EASTWARD CANNOT
BE RULED OUT THROUGH THE NIGHT... AND A FEW OF THESE COULD PRODUCE
LOCALLY HEAVY DOWNPOURS DUE TO THEIR SLOW MOVEMENT. OTHERWISE...
EXPECT AREAS OF FOG AND STRATUS TO FORM ESPECIALLY ACROSS THE
NORTHERN HALF WHERE PARTIAL CLEARING AND MOIST GROUND WILL FOSTER
LOW CLOUD DEVELOPMENT... A SCENARIO CORROBORATED BY LATEST HRRR.
LOWS 68-73... FOLLOWING THE LATEST GLAMP GUIDANCE AND OBSERVED
TRENDS. -GIH
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 230 PM SATURDAY...
SURFACE BOUNDARY/TROUGH IS EXPECTED TO SETTLE SOUTH OF THE AREA ON
SUNDAY AS WEAK SURFACE HIGH PRESSURE OFF THE MID-ATLANTIC COAST
RIDGES SOUTHEASTWARD INTO THE AREA. ALOFT...NWLY FLOW ALOFT WILL
PREVAIL FOR ONE LAST PERIOD...WITH CENTRAL NC REMAINING POISED TO
SEE ADDITIONALLY SHORTWAVE IMPULSES MOVE THROUGH THE AREA.
ASSOCIATED DPVA COUPLED WITH DIURNAL HEATING COULD SUPPORT ISOLATED
TO SLIGHT CHANCE OF SHOWER/STORM JUST ABOUT ANYWHERE ACROSS THE
FORECAST AREA. LOW-LEVEL NELY FLOW WILL COOL THINGS OFF A BIT...WITH
12Z LOW-LEVEL THICKNESSES SUNDAY MORNING OF 1395M A GOOD 10 METERS
BELOW TYPICAL LATE JUNE THICKNESS VALUES. HIGHS RANGING MID 80S
NORTH TO NEAR 90 SOUTH.
HEIGHTS ALOFT BEGIN TO INCREASE OVER THE AREA SUNDAY NIGHT. SURFACE
RIDGE LOOKS TO HOLD IN PLACE BEFORE SUCCUMBING TO RETURN FLOW DURING
THE DAY ON MONDAY. MODELS CONTINUE HINT AT THE POTENTIAL FOR SOME
MORNING STRATUS LATE TOWARDS DAYBREAK. LOWS IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 210 PM SATURDAY...
HIGH PRESSURE RIDGING DOWN THE EAST COAST WILL GRADUALLY SHIFT
OFFSHORE DURING THE DAY ON MONDAY...ALLOWING MOISTURE TO BEGIN TO
INCREASE ON ITS BACK SIDE WITHIN THE RETURN FLOW. THEREFORE...
PRECIP CHANCES WILL INCREASE SLIGHTLY ON MONDAY...MOST NOTICEABLY
ACROSS THE WEST WITHIN THE BEST RETURN FLOW. NEVERTHELESS...COVERAGE
IS EXPECTED TO BE ISOLATED TO WIDELY SCATTERED AT BEST AS A MID
LEVEL RIDGE BUILDS OVERHEAD. HIGHS ARE EXPECTED TO BE IN THE
MID/UPPER 80S TO NEAR 90 DEGREES...WITH OVERNIGHT LOWS GENERALLY IN
THE MID/UPPER 60S TO NEAR 70 DEGREES.
PRECIP CHANCES...MOSTLY DIURNAL IN NATURE...WILL BEGIN TO INCREASE
EVEN MORE ON TUESDAY AND THEN PERSIST FOR THE REMAINDER OF THE LONG
TERM AS MOISTURE CONTINUES TO INCREASE WITHIN THE RETURN FLOW THAT
SETS UP ON THE BACKSIDE OF THE DEPARTING HIGH. IN ADDITION...FLOW
ALOFT WILL BECOME SOUTHWESTERLY (THUS INCREASING DEEP LAYER
MOISTURE) AS LARGE SCALE TROUGHING MOVES OVER THE GREAT LAKES/MS
RIVER VALLEY. SHORTWAVE TROUGHING WILL THEN PROGRESS EAST OVER THE
REGION WEDNESDAY INTO THURSDAY...PROVIDING ADDITIONAL FORCING FOR
PRECIP. RIDGING ALOFT (ALTHOUGH RATHER FLAT) WILL BUILD BACK OVER
THE AREA LATE INTO THE WEEK AND INTO EARLY NEXT WEEKEND...ALLOWING
SOME MID LEVEL DRYING TO OCCUR. NEVERTHELESS...MODERATE TO STRONG
INSTABILITY WILL RESULT IN CONTINUED PRECIP CHANCES...ALTHOUGH
COVERAGE MAY BE SLIGHTLY LESS. HIGHS WILL GENERALLY IN THE UPPER 80S
TO LOWER 90S TO START THE PERIOD WITH LOW TO MID 90S EXPECTED BY THE
END OF THE WEEK. OVERNIGHT LOWS WILL MOSTLY BE IN THE UPPER 60S TO
LOWER 70S.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 715 PM SATURDAY...
24 HOUR TAF PERIOD: MOST SHOWER AND THUNDERSTORM ACTIVITY AT THIS
HOUR AFFECTING SOUTHERN AND EASTERN SITES. THAT BEING SAID SCATTERED
CONVECTION ACROSS SW VA WILL MOVE SOUTHEASTWARD...POSSIBLY INTO THE
TRIAD OVER THE NEXT FEW HOURS ALTHOUGH CONFIDENCE THAT IT WILL HOLD
TOGETHER IS LOW. CHANCES FOR FOG AND LOW STRATUS APPEAR TO BE
FAVORABLE IN MOST SITES BUT WITH VARYING SEVERITY. KRWI WILL MOST
LIKELY HAVE THE MOST SUBSTANTIAL SUB-VFR CONDITIONS OVERNIGHT WITH
IFR CEILINGS AND MVFR VISIBILITIES EXPECTED ANYTIME AFTER 6Z THROUGH
SUNRISE. THE SAME CONDITIONS ARE ALSO POSSIBLE AT RDU BUT NOT AS
LIKELY. WITH HEAVY SHOWERS MOVING THROUGH KFAY...THERE COULD BE SOME
PERIODS OF FOG OVERNIGHT THERE AS WELL. KGSO AND KINT COULD SEE SOME
MVFR VISIBILITIES BUT CONFIDENCE IN THIS IS FAIRLY LOW IF THERE IS
NO MORE CONVECTION TONIGHT. WINDS WILL BE LIGHT AND VARIABLE
OVERNIGHT BUT GRADUALLY TURNING NORTH/NORTHEASTERLY AND INCREASING
TO NEAR 10 KNOTS AFTER SUNRISE. CONVECTIVE ALLOWING MODELS SHOWING
BEST ACTIVITY FOR SUNDAY AFTERNOON ACROSS THE NORTH AND EAST WITH
KRWI THE MOST LIKELY TO SEE THUNDERSTORMS. COVERAGE SHOULD BE LESS
THAN TODAY. WILL LEAVE ANY MENTION OUT OF THE TAFS AT THIS TIME.
LONG TERM: AFTER A RELATIVE LULL IN DIURNAL CONVECTION SUNDAY AND
MONDAY...CHANCES WILL INCREASE FOR SHOWERS AND THUNDERSTORMS FOR
MIDWEEK. THERE WILL BE A CHANCE FOR FOG/LOW STRATUS EACH MORNING
TUESDAY THROUGH THURSDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...HARTFIELD
SHORT TERM...CBL
LONG TERM...KRD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 PM EDT FRI JUN 20 2014
.SYNOPSIS...A SERIES OF UPPER LEVEL DISTURBANCES WILL TRACK
SOUTHEAST ACROSS THE MID ATLANTIC AND CAROLINAS THIS EVENING AND
SATURDAY... PROPELLING A BACK DOOR COLD FRONT SOUTHWARD THROUGH
CENTRAL NORTH CAROLINA BY SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 1045 AM FRIDAY...
JUST MINOR ADJUSTMENTS MADE TO THE CURRENT FORECAST FOR THE REST OF
TODAY. A BATCH OF CONVECTION NOW PUSHING INTO NW NC IS EXPECTED TO
CONTINUE PROPAGATING TOWARD THE SE FOR THE NEXT SEVERAL HOURS...
FOLLOWING THE WEAK STEERING FLOW NOTED ON 12Z UPPER AIR ANALYSES...
ALTHOUGH CONVECTIVE GROWTH AND PROPAGATION TODAY WILL BE LARGELY
DRIVEN BY COLD POOL MOTION. THE COLUMN HAS YET TO FULLY DESTABILIZE
THIS MORNING DESPITE BRIGHT SUNSHINE (OVER ALL BUT THE FAR NE)... AS
MILD MID LEVEL TEMPS ARE THUS FAR HOLDING MLCAPE TO 500 J/KG OR
LOWER WITH REMAINING CINH. THE WARMTH ALOFT WILL MAKE FOR WEAK MID
LEVEL LAPSE RATES... AND WITH DEEP LAYER SHEAR REMAINING QUITE
WEAK... ORGANIZED CONVECTION WILL BE TOUCH TO ACHIEVE. LATEST
SURFACE ANALYSIS SHOWS A WEAK FRONTAL ZONE ACROSS NE NC... AND IT IS
ALONG AND NE OF THIS ZONE THAT LOW CLOUDS MAY HINDER HEATING AND
CURB INSTABILITY TO LIMIT SHOWER/STORM COVERAGE... AND WILL MAINTAIN
THE LOWEST POPS HERE... WITH BETTER COVERAGE OVER THE NW PIEDMONT BY
EARLY/MID AFTERNOON SPREADING OVER THE SOUTHERN THIRD OF CENTRAL NC
DURING THE LATE AFTERNOON INTO EARLY EVENING. THIS SCENARIO IS
REPRESENTED WELL BY THE LATEST HIGH-RES WRF-ARW AND WRF-NMM RUNS.
THE NAM/GFS DEPICT MODERATE INSTABILITY ONLY IN THE SE CWA THIS
AFTERNOON... REASONABLE GIVEN THE OVERALL LOW MID LEVEL LAPSE
RATES... AND WITH ANY CONVECTION LIKELY TO BE PULSE IN NATURE... THE
RISK OF SEVERE STORMS WILL BE SMALLER THAN IN RECENT DAYS. DOWNDRAFT
CAPE IS CURRENTLY VERY LOW BUT THE RAP PREDICTS IT TO RISE RAPIDLY
TO OVER 1000 J/KG BY 20Z... SO WE CAN`T RULE OUT A DAMAGING
DOWNBURST GUST WITH ANY STORMS. STORM COVERAGE IS STILL EXPECTED TO
RISE BY EVENING WITH THE APPROACH OF A MID LEVEL PERTURBATION FROM
THE NNW... THAT WILL TRACK SOUTHWARD THROUGH THE AREA... AND WILL
HOLD ONTO GOOD CHANCE POPS STARTING THIS EVENING MAINLY IN THE
NORTH. EARLIER FORECAST HIGHS FROM 88 (NE) TO 95 (SW) LOOK GOOD AND
ARE IN LINE WITH LATEST TRENDS. -GIH
PREVIOUS 255 AM DISCUSSION FOR TONIGHT: MODEL GUIDANCE INDICATES
RELATIVELY ROBUST SHORTWAVE ENERGY WILL TRACK SOUTHEAST INTO THE MID-
ATLANTIC AND CAROLINAS LATE THIS EVENING AND TONIGHT (03-12Z SAT).
DURING THIS TIME...LOW-LEVEL FLOW WILL BACK/STRENGTHEN TO 10-15 KT
IN RESPONSE TO DPVA AND 20-30 METER 12-HR H5 HEIGHT
FALLS...RESULTING IN WEAK LOW-LEVEL WARM ADVECTION BETWEEN 06-12Z
AND 500-1000 J/KG OF MUCAPE IN ASSOC/W AN INCREASINGLY WARM/MOIST
LOW-LEVEL AIRMASS AND ~6 C/KM MID-LEVEL LAPSE RATES. WITH THE ABOVE
IN MIND...WILL INDICATE A 20-30% CHANCE OF CONVECTION ACROSS THE
AREA THIS AFTERNOON...WITH INCREASING CHANCES (30-50%) OVERNIGHT.
SATURDAY IS EXPECTED TO BE CONVECTIVELY ACTIVE AGAIN AS THE FINAL
SHOT OF UPPER LEVEL ENERGY IS EXPECTED TO CLIP THE REGION AS THE
MAIN LOW LEVEL FOCUS (THE COLD FRONT) SAGS SOUTHWARD THROUGH THE
REGION. THE COMBINATION OF THE PIEDMONT TROUGH AND THE SOUTHWARD
MOVING COLD FRONT SHOULD INDUCE GOOD CONVERGENCE. STRONG SURFACE
HEATING SHOULD ADD PLENTY OF ENERGY FOR LIFT. THEREFORE... ISOLATED
SEVERE STORMS WILL BE POSSIBLE WITH THE MAIN THREAT OF DAMAGING
WIND. WE WILL BUMP THE POP UPWARD INTO THE LIKELY CATEGORY DURING
THE AFTERNOON AND EVENING... TAPERING FROM THE NORTH DURING SATURDAY
EVENING. LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING WILL POSE WEATHER
HAZARDS. HIGHS GENERALLY 85-90 EXCEPT LOWER 90S OVER THE SANDHILLS
BEFORE THE CONVECTION OCCURS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 230 PM FRIDAY...
SURFACE LOW PRESSURE WILL BE MOVING OFFSHORE TO BEGIN THE DAY ON
SUNDAY...WITH HIGH PRESSURE GRADUALLY BUILDING EAST AND DOWN THE
EAST COAST THROUGH MONDAY. THIS WILL PUSH A FRONT FURTHER SOUTH OF
THE FORECAST AREA...LIKELY INTO SC/GA. IN ADDITION...SHORTWAVE
RIDGING WILL ALSO BUILD EAST OVER THE REGION. THEREFORE...THIS TIME
FRAME OF ENTIRE FORECAST PERIOD IS WHEN PRECIP CHANCES WILL BE THE
LOWEST... ALTHOUGH NON-ZERO. SUNDAY SHOULD BE THE DRIEST DAY (WITH
ONLY A FEW ISOLATED STORMS EXPECTED)...THEN MAYBE SOME HIGHER
CHANCES ACROSS THE WEST ON MONDAY AS THE HIGH STARTS TO PULL AWAY
AND MOISTURE BEGINS TO INCREASE ON THE BACK SIDE OF THE DEPARTING
HIGH. TEMPS WILL BE A SEVERAL DEGREES LOWER THAN PREVIOUS DAYS BEHIND
THE FRONT...WITH HIGHS EXPECTED TO BE IN THE MID/UPPER 80S TO NEAR
90 DEGREES AND OVERNIGHT LOWS IN THE MID/UPPER 60S TO NEAR 70
DEGREES.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 230 PM FRIDAY...
PRECIP CHANCES...MOSTLY DIURNAL IN NATURE...WILL BEGIN TO INCREASE
ON TUESDAY AND THEN PERSIST FOR THE REMAINDER OF THE WEEK AS
MOISTURE INCREASES WITHIN THE RETURN FLOW THAT SETS UP ON THE
BACKSIDE OF THE DEPARTING HIGH. IN ADDITION...FLOW ALOFT WILL BECOME
SOUTHWESTERLY (THUS INCREASING DEEP LAYER MOISTURE) AS LARGE SCALE
TROUGHING MOVES OVER THE GREAT LAKES AND MS RIVER VALLEY.
ADDITIONALLY...TEMPS WILL CLIMB A FEW DEGREES...WITH HIGHS GENERALLY
IN THE UPPER 80S TO LOWER 90S AND OVERNIGHT LOWS IN THE UPPER 60S TO
LOWER 70S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 130 PM FRIDAY...
LATEST SURFACE MAP SHOWS A FRONTAL ZONE EXTENDING FROM NEAR CHI
ACROSS VA... WITH A SECONDARY WEAKER FRONT SOUTH OF HERE ACROSS NE
NC. MVFR CIGS OVER THE NE CWA (JUST NE OF RWI) HAVE LARGELY MIXED
OUT AND/OR RISEN ABOVE 3 KFT... AND CONVECTIVE CLOUDS THAT HAVE
DEVELOPED THUS FAR THIS AFTERNOON ARE LIKEWISE BASED ABOVE 3 KFT
AGL. HIGH CONFIDENCE THAT VFR CONDITIONS WILL CONTINUE TO DOMINATE
THROUGH THIS EVENING... WITH A BATCH OF MID CLOUDS POISED TO AFFECT
INT/GSO THIS AFTERNOON... ALTHOUGH CERTAINLY SUB-VFR CONDITIONS AND
GUSTY/VARIABLE WINDS ARE LIKELY IN AND NEAR SCATTERED STORMS. ANY
STORMS THAT FORM ARE MOST LIKELY TO AFFECT INT 18Z-22Z... GSO 19Z-
23Z... AND RDU/RWI/FAY 22Z-03Z... BUT THE STORM RISK IS NOT
RESTRICTED TO THESE WINDOWS. IN FACT... THE APPROACH OF A
DISTURBANCE INTO NORTHERN NC LATE TONIGHT IS LIKELY TO BRING ANOTHER
ROUND OF ISOLATED TO SCATTERED STORMS WARRANTING A VCTS MENTION
OVERNIGHT. WITH LIGHT WINDS AND HIGH HUMIDITY AND POSSIBLY A WET
GROUND LATE TONIGHT... THERE IS A CHANCE OF MVFR FOG AND IFR STRATUS
AT RWI/FAY IN THE FEW HOURS BEFORE DAYBREAK SAT. THE AFOREMENTIONED
DISTURBANCE WILL SINK INTO SRN/ERN PARTS OF NC SAT... A COULD SPAWN
SHOWER/STORM DEVELOPMENT NEAR FAY PRIOR TO 18Z.
LOOKING BEYOND 18Z SAT: VFR CONDITIONS AND LIGHT SURFACE WINDS WILL
DOMINATE INTO THE EVENING... WITH THE EXCEPTION OF IN AND NEAR ANY
SCATTERED STORMS WHERE GUSTY/VARIABLE WINDS AND SUB-VFR CONDITIONS
COULD BRIEFLY OCCUR. GOOD CHANCE OF SUB-VFR CIGS LATE SAT NIGHT INTO
SUN MORNING. EXPECT A RELATIVE MINIMUM IN STORM CHANCES ON SUNDAY AS
THE FRONT SETTLES TO OUR SOUTH BEFORE WASHING OUT AND DISSIPATING.
DAILY SHOWERS/STORMS RETURN MON-WED... MAINLY IN THE TYPICAL
AFTERNOON THROUGH EARLY EVENING HOURS. SUB-VFR FOG/STRATUS POSSIBLE
AT ALL SITES EARLY TUE AND EARLY WED MORNING. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...KRD
LONG TERM...KRD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
130 PM EDT FRI JUN 20 2014
.SYNOPSIS...A SERIES OF UPPER LEVEL DISTURBANCES WILL TRACK
SOUTHEAST ACROSS THE MID ATLANTIC AND CAROLINAS THIS EVENING AND
SATURDAY... PROPELLING A BACK DOOR COLD FRONT SOUTHWARD THROUGH
CENTRAL NORTH CAROLINA BY SATURDAY NIGHT.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1045 AM FRIDAY...
JUST MINOR ADJUSTMENTS MADE TO THE CURRENT FORECAST FOR THE REST OF
TODAY. A BATCH OF CONVECTION NOW PUSHING INTO NW NC IS EXPECTED TO
CONTINUE PROPAGATING TOWARD THE SE FOR THE NEXT SEVERAL HOURS...
FOLLOWING THE WEAK STEERING FLOW NOTED ON 12Z UPPER AIR ANALYSES...
ALTHOUGH CONVECTIVE GROWTH AND PROPAGATION TODAY WILL BE LARGELY
DRIVEN BY COLD POOL MOTION. THE COLUMN HAS YET TO FULLY DESTABILIZE
THIS MORNING DESPITE BRIGHT SUNSHINE (OVER ALL BUT THE FAR NE)... AS
MILD MID LEVEL TEMPS ARE THUS FAR HOLDING MLCAPE TO 500 J/KG OR
LOWER WITH REMAINING CINH. THE WARMTH ALOFT WILL MAKE FOR WEAK MID
LEVEL LAPSE RATES... AND WITH DEEP LAYER SHEAR REMAINING QUITE
WEAK... ORGANIZED CONVECTION WILL BE TOUCH TO ACHIEVE. LATEST
SURFACE ANALYSIS SHOWS A WEAK FRONTAL ZONE ACROSS NE NC... AND IT IS
ALONG AND NE OF THIS ZONE THAT LOW CLOUDS MAY HINDER HEATING AND
CURB INSTABILITY TO LIMIT SHOWER/STORM COVERAGE... AND WILL MAINTAIN
THE LOWEST POPS HERE... WITH BETTER COVERAGE OVER THE NW PIEDMONT BY
EARLY/MID AFTERNOON SPREADING OVER THE SOUTHERN THIRD OF CENTRAL NC
DURING THE LATE AFTERNOON INTO EARLY EVENING. THIS SCENARIO IS
REPRESENTED WELL BY THE LATEST HIGH-RES WRF-ARW AND WRF-NMM RUNS.
THE NAM/GFS DEPICT MODERATE INSTABILITY ONLY IN THE SE CWA THIS
AFTERNOON... REASONABLE GIVEN THE OVERALL LOW MID LEVEL LAPSE
RATES... AND WITH ANY CONVECTION LIKELY TO BE PULSE IN NATURE... THE
RISK OF SEVERE STORMS WILL BE SMALLER THAN IN RECENT DAYS. DOWNDRAFT
CAPE IS CURRENTLY VERY LOW BUT THE RAP PREDICTS IT TO RISE RAPIDLY
TO OVER 1000 J/KG BY 20Z... SO WE CAN`T RULE OUT A DAMAGING
DOWNBURST GUST WITH ANY STORMS. STORM COVERAGE IS STILL EXPECTED TO
RISE BY EVENING WITH THE APPROACH OF A MID LEVEL PERTURBATION FROM
THE NNW... THAT WILL TRACK SOUTHWARD THROUGH THE AREA... AND WILL
HOLD ONTO GOOD CHANCE POPS STARTING THIS EVENING MAINLY IN THE
NORTH. EARLIER FORECAST HIGHS FROM 88 (NE) TO 95 (SW) LOOK GOOD AND
ARE IN LINE WITH LATEST TRENDS. -GIH
PREVIOUS 255 AM DISCUSSION FOR TONIGHT: MODEL GUIDANCE INDICATES
RELATIVELY ROBUST SHORTWAVE ENERGY WILL TRACK SOUTHEAST INTO THE MID-
ATLANTIC AND CAROLINAS LATE THIS EVENING AND TONIGHT (03-12Z SAT).
DURING THIS TIME...LOW-LEVEL FLOW WILL BACK/STRENGTHEN TO 10-15 KT
IN RESPONSE TO DPVA AND 20-30 METER 12-HR H5 HEIGHT
FALLS...RESULTING IN WEAK LOW-LEVEL WARM ADVECTION BETWEEN 06-12Z
AND 500-1000 J/KG OF MUCAPE IN ASSOC/W AN INCREASINGLY WARM/MOIST
LOW-LEVEL AIRMASS AND ~6 C/KM MID-LEVEL LAPSE RATES. WITH THE ABOVE
IN MIND...WILL INDICATE A 20-30% CHANCE OF CONVECTION ACROSS THE
AREA THIS AFTERNOON...WITH INCREASING CHANCES (30-50%) OVERNIGHT.
-VINCENT
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 120 AM FRIDAY...
SATURDAY IS EXPECTED TO BE CONVECTIVELY ACTIVE AGAIN AS THE FINAL
SHOT OF UPPER LEVEL ENERGY IS EXPECTED TO CLIP THE REGION AS THE
MAIN LOW LEVEL FOCUS (THE COLD FRONT) SAGS SOUTHWARD THROUGH THE
REGION. THE COMBINATION OF THE PIEDMONT TROUGH AND THE SOUTHWARD
MOVING COLD FRONT SHOULD INDUCE GOOD CONVERGENCE. STRONG SURFACE
HEATING SHOULD ADD PLENTY OF ENERGY FOR LIFT. THEREFORE... ISOLATED
SEVERE STORMS WILL BE POSSIBLE WITH THE MAIN THREAT OF DAMAGING
WIND. WE WILL BUMP THE POP UPWARD INTO THE LIKELY CATEGORY DURING
THE AFTERNOON AND EVENING... TAPERING FROM THE NORTH DURING SATURDAY
EVENING. LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING WILL POSE WEATHER
HAZARDS. HIGHS GENERALLY 85-90 EXCEPT LOWER 90S OVER THE SANDHILLS
BEFORE THE CONVECTION OCCURS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 105 AM FRIDAY...
THE EXTENDED FORECAST GENERALLY REMAINS THE SAME AS IN PREVIOUS
DISCUSSIONS. THE MAIN COLD FRONT SHOULD STALL SOUTH OF THE REGION...
DEEP INTO SC/GA SUNDAY AND MONDAY. THIS WOULD HAVE SOME IMPACTS ON
SENSIBLE WEATHER INCLUDING LOWER POP SUNDAY AND MONDAY... BEFORE
RAMPING UP AGAIN MIDWEEK. IN ADDITION... THE TEMPERATURES WILL BE
COOLER THAN IN THE RECENT EARLY HEAT SPELL SUNDAY AND MONDAY AS THE
WINDS BECOME NE-E.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 130 PM FRIDAY...
LATEST SURFACE MAP SHOWS A FRONTAL ZONE EXTENDING FROM NEAR CHI
ACROSS VA... WITH A SECONDARY WEAKER FRONT SOUTH OF HERE ACROSS NE
NC. MVFR CIGS OVER THE NE CWA (JUST NE OF RWI) HAVE LARGELY MIXED
OUT AND/OR RISEN ABOVE 3 KFT... AND CONVECTIVE CLOUDS THAT HAVE
DEVELOPED THUS FAR THIS AFTERNOON ARE LIKEWISE BASED ABOVE 3 KFT
AGL. HIGH CONFIDENCE THAT VFR CONDITIONS WILL CONTINUE TO DOMINATE
THROUGH THIS EVENING... WITH A BATCH OF MID CLOUDS POISED TO AFFECT
INT/GSO THIS AFTERNOON... ALTHOUGH CERTAINLY SUB-VFR CONDITIONS AND
GUSTY/VARIABLE WINDS ARE LIKELY IN AND NEAR SCATTERED STORMS. ANY
STORMS THAT FORM ARE MOST LIKELY TO AFFECT INT 18Z-22Z... GSO 19Z-
23Z... AND RDU/RWI/FAY 22Z-03Z... BUT THE STORM RISK IS NOT
RESTRICTED TO THESE WINDOWS. IN FACT... THE APPROACH OF A
DISTURBANCE INTO NORTHERN NC LATE TONIGHT IS LIKELY TO BRING ANOTHER
ROUND OF ISOLATED TO SCATTERED STORMS WARRANTING A VCTS MENTION
OVERNIGHT. WITH LIGHT WINDS AND HIGH HUMIDITY AND POSSIBLY A WET
GROUND LATE TONIGHT... THERE IS A CHANCE OF MVFR FOG AND IFR STRATUS
AT RWI/FAY IN THE FEW HOURS BEFORE DAYBREAK SAT. THE AFOREMENTIONED
DISTURBANCE WILL SINK INTO SRN/ERN PARTS OF NC SAT... A COULD SPAWN
SHOWER/STORM DEVELOPMENT NEAR FAY PRIOR TO 18Z.
LOOKING BEYOND 18Z SAT: VFR CONDITIONS AND LIGHT SURFACE WINDS WILL
DOMINATE INTO THE EVENING... WITH THE EXCEPTION OF IN AND NEAR ANY
SCATTERED STORMS WHERE GUSTY/VARIABLE WINDS AND SUB-VFR CONDITIONS
COULD BRIEFLY OCCUR. GOOD CHANCE OF SUB-VFR CIGS LATE SAT NIGHT INTO
SUN MORNING. EXPECT A RELATIVE MINIMUM IN STORM CHANCES ON SUNDAY AS
THE FRONT SETTLES TO OUR SOUTH BEFORE WASHING OUT AND DISSIPATING.
DAILY SHOWERS/STORMS RETURN MON-WED... MAINLY IN THE TYPICAL
AFTERNOON THROUGH EARLY EVENING HOURS. SUB-VFR FOG/STRATUS POSSIBLE
AT ALL SITES EARLY TUE AND EARLY WED MORNING. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...32
LONG TERM...32
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1045 AM EDT FRI JUN 20 2014
.SYNOPSIS...A SERIES OF UPPER LEVEL DISTURBANCES WILL TRACK
SOUTHEAST ACROSS THE MID ATLANTIC AND CAROLINAS TODAY AND
SATURDAY... PROPELLING A BACK DOOR COLD FRONT SOUTHWARD THROUGH
CENTRAL NORTH CAROLINA BY SATURDAY NIGHT.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 1045 AM FRIDAY...
JUST MINOR ADJUSTMENTS MADE TO THE CURRENT FORECAST FOR THE REST OF
TODAY. A BATCH OF CONVECTION NOW PUSHING INTO NW NC IS EXPECTED TO
CONTINUE PROPAGATING TOWARD THE SE FOR THE NEXT SEVERAL HOURS...
FOLLOWING THE WEAK STEERING FLOW NOTED ON 12Z UPPER AIR ANALYSES...
ALTHOUGH CONVECTIVE GROWTH AND PROPAGATION TODAY WILL BE LARGELY
DRIVEN BY COLD POOL MOTION. THE COLUMN HAS YET TO FULLY DESTABILIZE
THIS MORNING DESPITE BRIGHT SUNSHINE (OVER ALL BUT THE FAR NE)... AS
MILD MID LEVEL TEMPS ARE THUS FAR HOLDING MLCAPE TO 500 J/KG OR
LOWER WITH REMAINING CINH. THE WARMTH ALOFT WILL MAKE FOR WEAK MID
LEVEL LAPSE RATES... AND WITH DEEP LAYER SHEAR REMAINING QUITE
WEAK... ORGANIZED CONVECTION WILL BE TOUCH TO ACHIEVE. LATEST
SURFACE ANALYSIS SHOWS A WEAK FRONTAL ZONE ACROSS NE NC... AND IT IS
ALONG AND NE OF THIS ZONE THAT LOW CLOUDS MAY HINDER HEATING AND
CURB INSTABILITY TO LIMIT SHOWER/STORM COVERAGE... AND WILL MAINTAIN
THE LOWEST POPS HERE... WITH BETTER COVERAGE OVER THE NW PIEDMONT BY
EARLY/MID AFTERNOON SPREADING OVER THE SOUTHERN THIRD OF CENTRAL NC
DURING THE LATE AFTERNOON INTO EARLY EVENING. THIS SCENARIO IS
REPRESENTED WELL BY THE LATEST HIGH-RES WRF-ARW AND WRF-NMM RUNS.
THE NAM/GFS DEPICT MODERATE INSTABILITY ONLY IN THE SE CWA THIS
AFTERNOON... REASONABLE GIVEN THE OVERALL LOW MID LEVEL LAPSE
RATES... AND WITH ANY CONVECTION LIKELY TO BE PULSE IN NATURE... THE
RISK OF SEVERE STORMS WILL BE SMALLER THAN IN RECENT DAYS. DOWNDRAFT
CAPE IS CURRENTLY VERY LOW BUT THE RAP PREDICTS IT TO RISE RAPIDLY
TO OVER 1000 J/KG BY 20Z... SO WE CAN`T RULE OUT A DAMAGING
DOWNBURST GUST WITH ANY STORMS. STORM COVERAGE IS STILL EXPECTED TO
RISE BY EVENING WITH THE APPROACH OF A MID LEVEL PERTURBATION FROM
THE NNW... THAT WILL TRACK SOUTHWARD THROUGH THE AREA... AND WILL
HOLD ONTO GOOD CHANCE POPS STARTING THIS EVENING MAINLY IN THE
NORTH. EARLIER FORECAST HIGHS FROM 88 (NE) TO 95 (SW) LOOK GOOD AND
ARE IN LINE WITH LATEST TRENDS. -GIH
PREVIOUS 255 AM DISCUSSION FOR TONIGHT: MODEL GUIDANCE INDICATES
RELATIVELY ROBUST SHORTWAVE ENERGY WILL TRACK SOUTHEAST INTO THE MID-
ATLANTIC AND CAROLINAS LATE THIS EVENING AND TONIGHT (03-12Z SAT).
DURING THIS TIME...LOW-LEVEL FLOW WILL BACK/STRENGTHEN TO 10-15 KT
IN RESPONSE TO DPVA AND 20-30 METER 12-HR H5 HEIGHT
FALLS...RESULTING IN WEAK LOW-LEVEL WARM ADVECTION BETWEEN 06-12Z
AND 500-1000 J/KG OF MUCAPE IN ASSOC/W AN INCREASINGLY WARM/MOIST
LOW-LEVEL AIRMASS AND ~6 C/KM MID-LEVEL LAPSE RATES. WITH THE ABOVE
IN MIND...WILL INDICATE A 20-30% CHANCE OF CONVECTION ACROSS THE
AREA THIS AFTERNOON...WITH INCREASING CHANCES (30-50%) OVERNIGHT.
-VINCENT
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 120 AM FRIDAY...
SATURDAY IS EXPECTED TO BE CONVECTIVELY ACTIVE AGAIN AS THE FINAL
SHOT OF UPPER LEVEL ENERGY IS EXPECTED TO CLIP THE REGION AS THE
MAIN LOW LEVEL FOCUS (THE COLD FRONT) SAGS SOUTHWARD THROUGH THE
REGION. THE COMBINATION OF THE PIEDMONT TROUGH AND THE SOUTHWARD
MOVING COLD FRONT SHOULD INDUCE GOOD CONVERGENCE. STRONG SURFACE
HEATING SHOULD ADD PLENTY OF ENERGY FOR LIFT. THEREFORE... ISOLATED
SEVERE STORMS WILL BE POSSIBLE WITH THE MAIN THREAT OF DAMAGING
WIND. WE WILL BUMP THE POP UPWARD INTO THE LIKELY CATEGORY DURING
THE AFTERNOON AND EVENING... TAPERING FROM THE NORTH DURING SATURDAY
EVENING. LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING WILL POSE WEATHER
HAZARDS. HIGHS GENERALLY 85-90 EXCEPT LOWER 90S OVER THE SANDHILLS
BEFORE THE CONVECTION OCCURS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 105 AM FRIDAY...
THE EXTENDED FORECAST GENERALLY REMAINS THE SAME AS IN PREVIOUS
DISCUSSIONS. THE MAIN COLD FRONT SHOULD STALL SOUTH OF THE REGION...
DEEP INTO SC/GA SUNDAY AND MONDAY. THIS WOULD HAVE SOME IMPACTS ON
SENSIBLE WEATHER INCLUDING LOWER POP SUNDAY AND MONDAY... BEFORE
RAMPING UP AGAIN MIDWEEK. IN ADDITION... THE TEMPERATURES WILL BE
COOLER THAN IN THE RECENT EARLY HEAT SPELL SUNDAY AND MONDAY AS THE
WINDS BECOME NE-E.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 645 AM FRIDAY...
24-HR TAF PERIOD: ASIDE FROM A POTENTIAL FOR ISOLD CONVECTION AT ANY
TERMINAL THIS AFTERNOON (18-00Z)...VFR CONDITIONS AND LIGHT WINDS
WILL PREVAIL THROUGH 00Z THIS EVENING. SIGNIFICANT UNCERTAINTY
PERSISTS WITH REGARD TO THE TIMING AND COVERAGE OF CONVECTION
TODAY...PRECLUDING EXPLICIT MENTION OF CONVECTION THIS AFTERNOON IN
THE 12Z TAF ISSUANCE. THE LATEST MODEL GUIDANCE SUGGESTS THE BEST
POTENTIAL FOR (AND COVERAGE OF) CONVECTION WILL BE THIS EVENING
THROUGH TONIGHT (00-12Z SAT) WHEN MORE ROBUST UPPER LEVEL
DISTURBANCES ARE PROGGED TO TRACK INTO THE REGION FROM THE
NORTHWEST. AS A RESULT...WILL INTRODUCE VCSH AT ALL TERMINALS
BEGINNING AT 00Z FOR AN INCREASED POTENTIAL OF SHOWERS/STORMS
LATER THIS EVENING THROUGH TONIGHT.
LOOKING AHEAD: SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE
EXPECTED ON SATURDAY IN ASSOC/W UPPER LEVEL DISTURBANCES IN NW FLOW
ALOFT...ESP AT THE RDU/RWI/FAY TERMINALS WHERE ISOLD SVR CONVECTION
WILL BE POSSIBLE DURING THE AFT/EVE HOURS. ASIDE FROM A POTENTIAL
FOR ISOLD TO SCT CONVECTION DURING THE AFT/EVE AND A POTENTIAL FOR A
BRIEF PERIOD OF PRE-DAWN FOG OR STRATUS...VFR CONDITIONS WILL
PREVAIL SUN-WED. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...32
LONG TERM...32
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1019 PM CDT SAT JUN 21 2014
.UPDATE...
ISSUED AT 1013 PM CDT SAT JUN 21 2014
LATEST RAP MODEL AND NAM SHOW 35-40 KT LOW LEVEL JET ERN SD INTO
WCNTRL MN CURRENTLY AND IT WILL PUSH OFF TO THE EAST SLOWLY
TONIGHT. STILL GOT SOME CONCERNS THAT LEFT EDGE OF LOW LEVEL JET
WILL CAUSE SHOWERS AND A FEW STORMS TO RE-FORM OR MOVE BACK INTO
FAR SOUTHEASTERN NORTH DAKOTA IN A WIDESPREAD WAY..ENOUGH SO THAT
FELT NEED TO KEEP FLASH FLOOD WATCH OVER FAR SE ND AND EXTEND IT
TO 09Z. THIS MATCHES UP WITH BIS/ABR. THREAT FOR WIDESPREAD
CONVECTION I-94 NORTHWARD IN ND IS SMALL BUT DID KEEP SOME POPS IN
FCST FOR AREAS EAST OF HCO-GFK-COOPERSTOWN THRU THE NIGHT. SVR
TSTM WATCH EXPIRED AT 03Z AND SEVERE THREAT REST OF THE NIGHT IS
VERY LOW AS SFC CIN INCREASES AND CAPES IN THE 850 MB LAYER NOT
QUITE HIGH ENOUGH.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 230 PM CDT SAT JUN 21 2014
THE MAIN CHALLENGE WILL BE CONVECTION...HEAVY RAIN AND SEVERE
POTENTIAL LATER THIS AFTERNOON AND OVERNIGHT. THE GFS HAS
INITIALIZED A BIT BETTER THAN OTHER MODELS WITH SFC DEWPOINTS...SO
WILL UTILIZE.
FOR TONIGHT...SHOWERS AND STORMS WILL LIKELY BE ONGOING AROUND 00Z
IN CENTRAL/EASTERN ND. THERE SHOULD BE A GRADUAL SHIFT IN STORMS
TO THE EAST AS THE LLJ INCREASES ALONG WITH DEEP
MOISTURE/INSTABILITY. THE BEST CHANCES FOR SHOWERS AND STORMS
SHOULD OCCUR FROM 00-06Z IN THE FLASH FLOOD WATCH AREA IN THE RED
RIVER VALLEY. THERE WILL BE CHANCES FOR SHOWERS AND STORMS MOVING
INTO THE EASTERN AREAS BY LATE TONIGHT AS THE SHORTWAVE AND SFC
TROUGH MOVE SLOWLY EAST. CAN/T RULE OUT HEAVY RAIN ANYWHERE GIVEN
HIGH PWATS AND FAIRLY SLOW MOVING STORMS...SO WE WILL NEED TO
MONITOR BOTH FLOODING THREATS AND SEVERE THREATS THROUGH AT LEAST
6Z.
ON SUNDAY...THE THREAT FOR SHOWERS AND STORMS WILL MOVE INTO THE
EASTERN AREAS BY AFTERNOON. THERE COULD BE SOME LOCALLY HEAVY RAIN
INTO SATURATED AREAS OF MN LAKES COUNTRY...SO SOMETHING TO KEEP IN
MIND NEAR ANY SLOW MOVING THUNDERSTORMS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 230 PM CDT SAT JUN 21 2014
ON MONDAY...A FAIRLY STRONG UPPER WAVE WILL PUSH A COLD FRONT
SOUTH FROM CANADA. THIS WILL LEAD TO A GOOD CHANCE FOR SHOWERS AND
STORMS BY AFTERNOON IN THE NORTH MOVING SOUTH THROUGH MONDAY
NIGHT. TEMPS WILL BE A BIT COOLER...AND ONCE AGAIN WITH PWATS OVER
1 INCH...ANY SLOW MOVING STORMS WILL BE MONITORED GIVEN THE
SATURATED GROUND AND ONGOING FLOODING ISSUES.
ON TUE...THE SLOW MOVING UPPER LOW WILL REMAIN NEAR THE REGION.
THERE COULD BE SOME DRYING LATER IN THE DAY IN THE NORTH...BUT THE
ECMWF HANGS ONTO THE CHANCE FOR SHOWERS AND STORMS AND WILL JUST
MENTION 30 POPS FOR ALL AREAS...GIVEN SOME MODEL DIFFERENCES.
TEMPS WILL BE COOLER THAN RECENT DAYS WITH MID LEVEL COOLING AND
SHOWERS/STORMS AROUND FOR MUCH OF THE DAY.
FOR TUESDAY NIGHT THROUGH FRIDAY...MODELS IN GENERAL AGREEMENT AND
USED A BLENDED SOLN ATTM. TEMPERATURES START ON THE COOL SIDE AS THE
500MB LOW IS IN PLACE OVER THE DAKOTAS...BEFORE FILLING AND LIFTING
TO THE EAST. THE UPPER RIDGE BEGINS TO SHIFT EAST ACROSS THE AREA
LATER IN THE PERIOD...AND WILL BRING WARMER TEMPERATURES TO THE
REGION BY THE END OF THE TIME FRAME. OTHERWISE...WILL SEE SOME
IMPULSES MOVING THRU THE FLOW...BRINGING PERIODIC CHANCES FOR
-SHRA/-TSRA TO THE AREA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 720 PM CDT SAT JUN 21 2014
VFR CONDITIONS MOST OF THE TIME TONIGHT. BASES NEAR TSTMS 4-7KT
AND BEST BET FOR STORMS IN AREA WOULD BE FARGO REGION THRU 04Z OR
SO AND MAYBE BEMIDJI. DVL SEEMS TO BE IN THE CLEAR. EXPECT A
NORTHWEST WIND OR LIGHT/VARIABLE WIND OVERNIGHT INTO SUNDAY WITH
ONLY SOME CIRRUS OR SCATTERED HIGH BASED CU SUNDAY IN THE AREA.
&&
.HYDROLOGY...
ISSUED AT 1230 PM CDT SAT JUN 21 2014
RUNOFF FROM ALL THE RECENT RAINFALL OVER THE REGION
CONTINUES TO LEAD TO SEVERAL FORECAST POINTS ABOVE FLOOD STAGE ON
THE ND/MN TRIBS AND ON THE MAINSTEM RED. ABERCROMBIE ON THE WILD
RICE REMAINS IN MODERATE FLOOD STAGE...ALONG WITH SABIN ON S.
BUFFALO. ON THE RED...OSLO IS APPROACHING MODERATE WITH FARGO IN
MODERATE. ADDITIONAL SHOWERS AND THUNDERSTORMS LATE TODAY AND
TONIGHT MAY PRODUCE LOCALLY HEAVY RAINFALL...WHICH COULD IMPACT RIVER
FORECASTS...DEPENDING ON WHERE THE HEAVIEST PRECIP FALLS. THE AREAL
FLOOD WARNING CONTINUES FOR PARTS OF BELTRAMI COUNTY...WHERE THE
TAMARAC RIVER HAS BEEN OUT OF ITS BANKS NEAR WASKISH.
AN AREAL FLOOD WARNING REMAINS IN EFFECT FOR EAST CENTRAL BELTRAMI
COUNTY WITH THE TAMARAC RIVER OUT OF ITS BANKS NEAR WASKISH.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FLASH FLOOD WATCH UNTIL 4 AM CDT SUNDAY FOR NDZ049-052-053.
MN...FLASH FLOOD WATCH UNTIL 4 AM CDT SUNDAY FOR MNZ029.
&&
$$
UPDATE...RIDDLE
SHORT TERM...DK
LONG TERM...HOPKINS/DK
AVIATION...RIDDLE
HYDROLOGY...MAKOWSKI
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1256 PM CDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 1254 PM CDT FRI JUN 20 2014
NO CHANGES FROM PREVIOUS UPDATE.
UPDATE ISSUED AT 955 AM CDT FRI JUN 20 2014
NO MAJOR CHANGES TO THIS UPDATE. HAVE ADDED SOME THUNDER INTO THE
FAR SOUTHWEST THIS AFTERNOON...AND EXTENDED THUNDER CHANCES IN ALL
AREAS THROUGH 00Z. A STRONG SHORTWAVE...UPPER SPEED MAX AND
INSTABILITY SHOULD MEAN SCATTERED STORMS THIS AFTERNOON. THE DEEP
LAYERED SHEAR IS STRONG...AROUND 50-60KT...SO IF SFC DEWPOINTS CAN
RISE INTO THE MID 60S...CAPES AROUND 1500 J/KG WOULD OCCUR. THIS
WOULD BE ENOUGH FOR SOME SEVERE STORMS...WITH THE MAIN THREATS
LARGE HAIL AND DAMAGING WINDS. IT APPEARS THAT STORM INITIATION
SHOULD OCCUR NEAR THE VALLEY...WITH THE BEST SEVERE THREAT EAST OF
THE VALLEY. THIS IS IN LINE WITH THE LATEST SPC SLIGHT RISK AREA
MAINLY IN MN.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
PRECIP CHANCES AND STRENGTH WILL BE THE MAIN FORECAST ISSUE FOR
THE SHORT TERM.
UPPER LOW CURRENTLY CENTERED ALONG THE MT/CANADIAN BORDER...AND
MODELS ARE IN PRETTY GOOD AGREEMENT ON TRACKING THE UPPER LOW
SLOWLY EASTWARD TODAY. THERE WILL BE A STRONG VORT MAX/JET STREAK
COMING INTO THE CWA BY THIS AFTERNOON. WITH THE STRONG UPPER LEVEL
SYSTEM COMING THROUGH...BULK SHEAR VALUES WILL BE VERY STRONG...UP
IN THE 50 TO 60 KT RANGE ACROSS PORTIONS OF THE SOUTHERN CWA. MORE
IN QUESTION WILL BE THE INSTABILITY. THE NAM BRINGS CAPE VALUES OF
1500-2000 J/KG INTO OUR SOUTHEASTERN COUNTIES...AND THE RUC IS
SIMILAR BUT MORE IN THE 1000-1500 RANGE. STRATUS OVER THE EAST HAS
BEEN CLEARING OUT AND FOG HAS BEEN NOT VERY WIDESPREAD...SO THERE
SHOULD BE AT LEAST A LITTLE BIT OF HEATING THIS AFTERNOON.
HOWEVER...CLOUDS HAVE BEEN INCREASING OVER THE WESTERN COUNTIES
AND REGIONAL RADAR SHOWS QUITE A BIT OF ACTIVITY OVER WESTERN ND
WITH THE JET STREAK COMING OUT. THE UPPER SUPPORT MAY BE INTO THE
ARE BEFORE WE CAN DESTABILIZE ENOUGH. FOR THAT REASON...BUMPED UP
POPS AND WILL MENTION CHANCE OF SEVERE IN THE HWO...BUT WILL KEEP
A SEVERE MENTION OUT OF THE GRIDS FOR THE TIME BEING.
TONIGHT...THE MAIN UPPER LOW WILL LIFT NORTHEASTWARD INTO CANADA.
A FEW SHOWERS MAY BE HANGING AROUND THE NORTHEASTERN COUNTIES
EARLY ON BUT THINK THERE WILL BE A BREAK IN PRECIP FOR MUCH OF THE
NIGHT. CONTINUED TO KEEP TEMPS OVERNIGHT IN THE UPPER 50S TO LOW
60S. SUNSHINE AND SOUTH TO SOUTHWESTERLY SFC WINDS SHOULD HELP
HIGHS ON SATURDAY REACH THE 80S IN MANY AREAS. BY SATURDAY
AFTERNOON...A WEAK SHORTWAVE PUSHING IN FROM THE WEST WILL HELP
BRING A SFC TROUGH AXIS INTO CENTRAL ND AND THERE SHOULD BE SOME
CONVECTIVE ACTIVITY ALONG WITH IT. BULK SHEAR VALUES ARE QUITE A
BIT LOWER BUT THERE SHOULD BE DECENT INSTABILITY. WILL CONTINUE TO
KEEP CHANCE POPS GOING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
SATURDAY NIGHT THROUGH SUNDAY NIGHT...MORE SHORTWAVES MOVE THROUGH
AS THE ACTIVE PATTERN CONTINUES UNDER WEST TO SOUTHWESTERLY FLOW
ALOFT. THE MAIN SFC TROUGH WILL MOVE OFF TO THE EAST SATURDAY
NIGHT INTO SUNDAY...WITH SOME WEAK COLD AIR ADVECTION BEHIND IT.
THINK THAT BEST CHANCES FOR PRECIP WILL BE LATE SATURDAY NIGHT
INTO SUNDAY AS THIS FEATURE MOVES THROUGH. KEPT 20-40 POPS GOING
BEFORE TAPERING THEM OFF SUNDAY NIGHT. TEMPS ON SUNDAY WILL BE A
BIT LOWER THAN SATURDAY...MAINLY IN THE 70S.
MONDAY THROUGH THURSDAY...THIS PERIOD WILL BE CATEGORIZED BY MEAN
ZONAL FLOW...THE UPPER LOW HAVING DEPARTED TO THE EAST. SEVERAL
SHORT WAVE RIPPLES LIKELY TO MOVE THROUGH THIS FLOW...OFFERING
PCPN CHANCES PERHAPS TUESDAY AND AGAIN ON THURSDAY. BELIEVE THE
BEST BET FOR TOTALLY DRY WILL COME MIDWEEK...AS BOTH 00Z GFS/ECMWF
DEPICT A BUBBLE OF CANADIAN HIGH PRESSURE FOR WEDNESDAY.
LOOKS LIKE WARMEST DAY WILL BE MONDAY WITH COOLER READINGS UNDER
MORE CLOUD COVER TUESDAY...RECOVERING TO NEAR AVERAGE FOR LATE JUNE
BY WED/THUR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1254 PM CDT FRI JUN 20 2014
EXPECT VFR CONDITIONS THRU THE FORECAST PERIOD. OTHERWISE...MID
LEVEL CLOUDS WILL INCREASE ACROSS THE NORTHERN PART OF THE AREA AS
AN UPPER LEVEL DISTURBANCE CROSSES JUST SOUTH OF THE INTERNATIONAL
BORDER. LOOKING FOR MAINLY SHOWERS EARLY IN THE FCST PERIOD AS THE
UPPER DISTURBANCE MOVES EAST. HOWEVER...A GREATER RISK EXISTS FOR
SCATTERED TSTMS LATER THIS AFTERNOON...WITH A COMBINED INCREASE IN
SFC HEATING AND ENERGY ALOFT. WINDS ARE EXPECTED TO REMAIN GENERALLY
SOUTH TO SOUTHWEST AS SFC LOW PRESSURE CONTINUES TO AFFECT THE AREA.
&&
.HYDROLOGY...
ISSUED AT 1254 PM CDT FRI JUN 20 2014
RIVER FORECASTS ARE ON TRACK AS RISES CONTINUE AS
A RESULT OF THE RECENT RAINFALL. THE WILD RICE RIVER AT ABERCROMBIE
IS NEARING CREST WITHIN MODERATE FLOOD STAGE...AND FARGO AND OSLO ON
THE RED RIVER ARE EXPECTED TO REACH MODERATE FLOOD STAGE. THE FLOOD
WARNING ON THE BUFFALO RIVER AT HAWLEY HAS BEEN CANCELLED AS CURRENT
FORECASTS INDICATE GRADUALLY FALLING STAGES. NO OTHER SIGNIFICANT
CHANGES WERE MADE TO FORECAST POINTS. AN AREAL FLOOD WARNING REMAINS
IN EFFECT FOR EAST CENTRAL BELTRAMI COUNTY WITH THE TAMARAC RIVER
OUT OF ITS BANKS NEAR WASKISH.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...JR
LONG TERM...WJB
AVIATION...HOPKINS
HYDROLOGY...HOPKINS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1000 AM CDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 955 AM CDT FRI JUN 20 2014
NO MAJOR CHANGES TO THIS UPDATE. HAVE ADDED SOME THUNDER INTO THE
FAR SOUTHWEST THIS AFTERNOON...AND EXTENDED THUNDER CHANCES IN ALL
AREAS THROUGH 00Z. A STRONG SHORTWAVE...UPPER SPEED MAX AND
INSTABILITY SHOULD MEAN SCATTERED STORMS THIS AFTERNOON. THE DEEP
LAYERED SHEAR IS STRONG...AROUND 50-60KT...SO IF SFC DEWPOINTS CAN
RISE INTO THE MID 60S...CAPES AROUND 1500 J/KG WOULD OCCUR. THIS
WOULD BE ENOUGH FOR SOME SEVERE STORMS...WITH THE MAIN THREATS
LARGE HAIL AND DAMAGING WINDS. IT APPEARS THAT STORM INITIATION
SHOULD OCCUR NEAR THE VALLEY...WITH THE BEST SEVERE THREAT EAST OF
THE VALLEY. THIS IS IN LINE WITH THE LATEST SPC SLIGHT RISK AREA
MAINLY IN MN.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
PRECIP CHANCES AND STRENGTH WILL BE THE MAIN FORECAST ISSUE FOR
THE SHORT TERM.
UPPER LOW CURRENTLY CENTERED ALONG THE MT/CANADIAN BORDER...AND
MODELS ARE IN PRETTY GOOD AGREEMENT ON TRACKING THE UPPER LOW
SLOWLY EASTWARD TODAY. THERE WILL BE A STRONG VORT MAX/JET STREAK
COMING INTO THE CWA BY THIS AFTERNOON. WITH THE STRONG UPPER LEVEL
SYSTEM COMING THROUGH...BULK SHEAR VALUES WILL BE VERY STRONG...UP
IN THE 50 TO 60 KT RANGE ACROSS PORTIONS OF THE SOUTHERN CWA. MORE
IN QUESTION WILL BE THE INSTABILITY. THE NAM BRINGS CAPE VALUES OF
1500-2000 J/KG INTO OUR SOUTHEASTERN COUNTIES...AND THE RUC IS
SIMILAR BUT MORE IN THE 1000-1500 RANGE. STRATUS OVER THE EAST HAS
BEEN CLEARING OUT AND FOG HAS BEEN NOT VERY WIDESPREAD...SO THERE
SHOULD BE AT LEAST A LITTLE BIT OF HEATING THIS AFTERNOON.
HOWEVER...CLOUDS HAVE BEEN INCREASING OVER THE WESTERN COUNTIES
AND REGIONAL RADAR SHOWS QUITE A BIT OF ACTIVITY OVER WESTERN ND
WITH THE JET STREAK COMING OUT. THE UPPER SUPPORT MAY BE INTO THE
ARE BEFORE WE CAN DESTABILIZE ENOUGH. FOR THAT REASON...BUMPED UP
POPS AND WILL MENTION CHANCE OF SEVERE IN THE HWO...BUT WILL KEEP
A SEVERE MENTION OUT OF THE GRIDS FOR THE TIME BEING.
TONIGHT...THE MAIN UPPER LOW WILL LIFT NORTHEASTWARD INTO CANADA.
A FEW SHOWERS MAY BE HANGING AROUND THE NORTHEASTERN COUNTIES
EARLY ON BUT THINK THERE WILL BE A BREAK IN PRECIP FOR MUCH OF THE
NIGHT. CONTINUED TO KEEP TEMPS OVERNIGHT IN THE UPPER 50S TO LOW
60S. SUNSHINE AND SOUTH TO SOUTHWESTERLY SFC WINDS SHOULD HELP
HIGHS ON SATURDAY REACH THE 80S IN MANY AREAS. BY SATURDAY
AFTERNOON...A WEAK SHORTWAVE PUSHING IN FROM THE WEST WILL HELP
BRING A SFC TROUGH AXIS INTO CENTRAL ND AND THERE SHOULD BE SOME
CONVECTIVE ACTIVITY ALONG WITH IT. BULK SHEAR VALUES ARE QUITE A
BIT LOWER BUT THERE SHOULD BE DECENT INSTABILITY. WILL CONTINUE TO
KEEP CHANCE POPS GOING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
SATURDAY NIGHT THROUGH SUNDAY NIGHT...MORE SHORTWAVES MOVE THROUGH
AS THE ACTIVE PATTERN CONTINUES UNDER WEST TO SOUTHWESTERLY FLOW
ALOFT. THE MAIN SFC TROUGH WILL MOVE OFF TO THE EAST SATURDAY
NIGHT INTO SUNDAY...WITH SOME WEAK COLD AIR ADVECTION BEHIND IT.
THINK THAT BEST CHANCES FOR PRECIP WILL BE LATE SATURDAY NIGHT
INTO SUNDAY AS THIS FEATURE MOVES THROUGH. KEPT 20-40 POPS GOING
BEFORE TAPERING THEM OFF SUNDAY NIGHT. TEMPS ON SUNDAY WILL BE A
BIT LOWER THAN SATURDAY...MAINLY IN THE 70S.
MONDAY THROUGH THURSDAY...THIS PERIOD WILL BE CATEGORIZED BY MEAN
ZONAL FLOW...THE UPPER LOW HAVING DEPARTED TO THE EAST. SEVERAL
SHORT WAVE RIPPLES LIKELY TO MOVE THROUGH THIS FLOW...OFFERING
PCPN CHANCES PERHAPS TUESDAY AND AGAIN ON THURSDAY. BELIEVE THE
BEST BET FOR TOTALLY DRY WILL COME MIDWEEK...AS BOTH 00Z GFS/ECMWF
DEPICT A BUBBLE OF CANADIAN HIGH PRESSURE FOR WEDNESDAY.
LOOKS LIKE WARMEST DAY WILL BE MONDAY WITH COOLER READINGS UNDER
MORE CLOUD COVER TUESDAY...RECOVERING TO NEAR AVERAGE FOR LATE JUNE
BY WED/THUR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 657 AM CDT FRI JUN 20 2014
KBJI STILL HAS SOME 1/4SM BUT WEB CAMS SHOW FOG IS SHALLOW AND
PATCHY...SO HAVE IT ENDING BY 13Z. REST OF TAF SITES REMAIN VFR.
MID LEVEL CLOUDS WILL INCREASE FROM THE WEST THROUGHOUT THE DAY.
SOME SCATTERED SHOWERS WILL MOVE FROM THE KDVL AREA EASTWARD
THROUGHOUT THE DAY. SOME CONVECTION IS POSSIBLE LATER TODAY...BUT
FOR NOW MAINLY WENT WITH VCTS AS ACTIVITY WILL BE FAIRLY
SCATTERED. WINDS WILL SHIFT AROUND TO THE SOUTHWEST AND THEN TO
THE SOUTH BY THE END OF THE PERIOD.
&&
.HYDROLOGY...
ISSUED AT 252 PM CDT THU JUN 19 2014
RECENT HEAVY RAINS OVER THE RED RIVER BASIN IS CAUSING RISES ON
THE MAINSTEM RED RIVER AND MINNESOTA TRIBUTARIES. RAINFALL AMOUNTS
RANGED FROM 2.5 INCHES AROUND THE WAHPETON/BRECKENRIDGE AREA TO
AROUND A QUARTER INCH IN BELTRAMI AND LAKE OF THE WOODS COUNTIES.
WITH THE RAINFALL...NEW RIVER POINT WARNINGS HAVE BEEN ISSUED
RAISING ABERCROMBIE...FARGO AND OSLO TO MODERATE FLOOD STAGE.
AN AREAL FLOOD WARNING HAS BEEN ISSUED UNTIL NOON SUNDAY FOR EAST
CENTRAL BELTRAMI COUNTY. BELTRAMI COUNTY EMERGENCY MANAGEMENT
RELAYED THAT THE TAMARAC RIVER NEAR WASKISH IS WELL OUT OF ITS
BANKS. WATER IS SURROUNDING NUMEROUS HOUSES WITH A FEW ROADS WASHED
OUT...AND NUMEROUS AGRICULTURAL FIELDS ARE UNDER WATER. WATER IS
ALSO BEGINNING TO APPROACH THE BOTTOMS OF BRIDGES ALONG THE TAMARAC
RIVER. MORE WATER IS EXPECTED TO FLOW INTO THE TAMARAC RIVER...AND
THE SITUATION CONTINUES TO BE MONITORED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...JR
LONG TERM...WJB
AVIATION...JR
HYDROLOGY...HOPKINS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
657 AM CDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 657 AM CDT FRI JUN 20 2014
PATCHY FOG IN THE SOUTHEAST COUNTIES HAVE BROUGHT PKD AND BJI DOWN
TO 1/4SM AT TIMES THIS MORNING...BUT WEB CAMS SHOW THAT FOG IS
PATCHY AND SHALLOW. WILL CONTINUE TO KEEP A MENTION OF PATCHY FOG
IN THE GRIDS FOR THE NEXT FEW HOURS BUT THINK THAT THE FOG SHOULD
BURN OFF FAIRLY QUICKLY UNDER THE STRONG JUNE SUN. MID LEVEL
CLOUDS ARE INCREASING FROM THE EAST AND COULD STILL HAVE AN IMPACT
ON DESTABILIZATION LATER THIS AFTERNOON. MADE A FEW MINOR TWEAKS
TO POPS FOR SHOWERS THIS MORNING OVER OUR NORTHWESTERN
COUNTIES...BUT KEPT THE SCATTERED MENTION FOR LATER THIS
AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
PRECIP CHANCES AND STRENGTH WILL BE THE MAIN FORECAST ISSUE FOR
THE SHORT TERM.
UPPER LOW CURRENTLY CENTERED ALONG THE MT/CANADIAN BORDER...AND
MODELS ARE IN PRETTY GOOD AGREEMENT ON TRACKING THE UPPER LOW
SLOWLY EASTWARD TODAY. THERE WILL BE A STRONG VORT MAX/JET STREAK
COMING INTO THE CWA BY THIS AFTERNOON. WITH THE STRONG UPPER LEVEL
SYSTEM COMING THROUGH...BULK SHEAR VALUES WILL BE VERY STRONG...UP
IN THE 50 TO 60 KT RANGE ACROSS PORTIONS OF THE SOUTHERN CWA. MORE
IN QUESTION WILL BE THE INSTABILITY. THE NAM BRINGS CAPE VALUES OF
1500-2000 J/KG INTO OUR SOUTHEASTERN COUNTIES...AND THE RUC IS
SIMILAR BUT MORE IN THE 1000-1500 RANGE. STRATUS OVER THE EAST HAS
BEEN CLEARING OUT AND FOG HAS BEEN NOT VERY WIDESPREAD...SO THERE
SHOULD BE AT LEAST A LITTLE BIT OF HEATING THIS AFTERNOON.
HOWEVER...CLOUDS HAVE BEEN INCREASING OVER THE WESTERN COUNTIES
AND REGIONAL RADAR SHOWS QUITE A BIT OF ACTIVITY OVER WESTERN ND
WITH THE JET STREAK COMING OUT. THE UPPER SUPPORT MAY BE INTO THE
ARE BEFORE WE CAN DESTABILIZE ENOUGH. FOR THAT REASON...BUMPED UP
POPS AND WILL MENTION CHANCE OF SEVERE IN THE HWO...BUT WILL KEEP
A SEVERE MENTION OUT OF THE GRIDS FOR THE TIME BEING.
TONIGHT...THE MAIN UPPER LOW WILL LIFT NORTHEASTWARD INTO CANADA.
A FEW SHOWERS MAY BE HANGING AROUND THE NORTHEASTERN COUNTIES
EARLY ON BUT THINK THERE WILL BE A BREAK IN PRECIP FOR MUCH OF THE
NIGHT. CONTINUED TO KEEP TEMPS OVERNIGHT IN THE UPPER 50S TO LOW
60S. SUNSHINE AND SOUTH TO SOUTHWESTERLY SFC WINDS SHOULD HELP
HIGHS ON SATURDAY REACH THE 80S IN MANY AREAS. BY SATURDAY
AFTERNOON...A WEAK SHORTWAVE PUSHING IN FROM THE WEST WILL HELP
BRING A SFC TROUGH AXIS INTO CENTRAL ND AND THERE SHOULD BE SOME
CONVECTIVE ACTIVITY ALONG WITH IT. BULK SHEAR VALUES ARE QUITE A
BIT LOWER BUT THERE SHOULD BE DECENT INSTABILITY. WILL CONTINUE TO
KEEP CHANCE POPS GOING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
SATURDAY NIGHT THROUGH SUNDAY NIGHT...MORE SHORTWAVES MOVE THROUGH
AS THE ACTIVE PATTERN CONTINUES UNDER WEST TO SOUTHWESTERLY FLOW
ALOFT. THE MAIN SFC TROUGH WILL MOVE OFF TO THE EAST SATURDAY
NIGHT INTO SUNDAY...WITH SOME WEAK COLD AIR ADVECTION BEHIND IT.
THINK THAT BEST CHANCES FOR PRECIP WILL BE LATE SATURDAY NIGHT
INTO SUNDAY AS THIS FEATURE MOVES THROUGH. KEPT 20-40 POPS GOING
BEFORE TAPERING THEM OFF SUNDAY NIGHT. TEMPS ON SUNDAY WILL BE A
BIT LOWER THAN SATURDAY...MAINLY IN THE 70S.
MONDAY THROUGH THURSDAY...THIS PERIOD WILL BE CATEGORIZED BY MEAN
ZONAL FLOW...THE UPPER LOW HAVING DEPARTED TO THE EAST. SEVERAL
SHORT WAVE RIPPLES LIKELY TO MOVE THROUGH THIS FLOW...OFFERING
PCPN CHANCES PERHAPS TUESDAY AND AGAIN ON THURSDAY. BELIEVE THE
BEST BET FOR TOTALLY DRY WILL COME MIDWEEK...AS BOTH 00Z GFS/ECMWF
DEPICT A BUBBLE OF CANADIAN HIGH PRESSURE FOR WEDNESDAY.
LOOKS LIKE WARMEST DAY WILL BE MONDAY WITH COOLER READINGS UNDER
MORE CLOUD COVER TUESDAY...RECOVERING TO NEAR AVERAGE FOR LATE JUNE
BY WED/THUR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 657 AM CDT FRI JUN 20 2014
KBJI STILL HAS SOME 1/4SM BUT WEB CAMS SHOW FOG IS SHALLOW AND
PATCHY...SO HAVE IT ENDING BY 13Z. REST OF TAF SITES REMAIN VFR.
MID LEVEL CLOUDS WILL INCREASE FROM THE WEST THROUGHOUT THE DAY.
SOME SCATTERED SHOWERS WILL MOVE FROM THE KDVL AREA EASTWARD
THROUGHOUT THE DAY. SOME CONVECTION IS POSSIBLE LATER TODAY...BUT
FOR NOW MAINLY WENT WITH VCTS AS ACTIVITY WILL BE FAIRLY
SCATTERED. WINDS WILL SHIFT AROUND TO THE SOUTHWEST AND THEN TO
THE SOUTH BY THE END OF THE PERIOD.
&&
.HYDROLOGY...
ISSUED AT 252 PM CDT THU JUN 19 2014
RECENT HEAVY RAINS OVER THE RED RIVER BASIN IS CAUSING RISES ON
THE MAINSTEM RED RIVER AND MINNESOTA TRIBUTARIES. RAINFALL AMOUNTS
RANGED FROM 2.5 INCHES AROUND THE WAHPETON/BRECKENRIDGE AREA TO
AROUND A QUARTER INCH IN BELTRAMI AND LAKE OF THE WOODS COUNTIES.
WITH THE RAINFALL...NEW RIVER POINT WARNINGS HAVE BEEN ISSUED
RAISING ABERCROMBIE...FARGO AND OSLO TO MODERATE FLOOD STAGE.
AN AREAL FLOOD WARNING HAS BEEN ISSUED UNTIL NOON SUNDAY FOR EAST
CENTRAL BELTRAMI COUNTY. BELTRAMI COUNTY EMERGENCY MANAGEMENT
RELAYED THAT THE TAMARAC RIVER NEAR WASKISH IS WELL OUT OF ITS
BANKS. WATER IS SURROUNDING NUMEROUS HOUSES WITH A FEW ROADS WASHED
OUT...AND NUMEROUS AGRICULTURAL FIELDS ARE UNDER WATER. WATER IS
ALSO BEGINNING TO APPROACH THE BOTTOMS OF BRIDGES ALONG THE TAMARAC
RIVER. MORE WATER IS EXPECTED TO FLOW INTO THE TAMARAC RIVER...AND
THE SITUATION CONTINUES TO BE MONITORED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...JR
LONG TERM...WJB
AVIATION...JR
HYDROLOGY...HOPKINS
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
335 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
PRECIP CHANCES AND STRENGTH WILL BE THE MAIN FORECAST ISSUE FOR
THE SHORT TERM.
UPPER LOW CURRENTLY CENTERED ALONG THE MT/CANADIAN BORDER...AND
MODELS ARE IN PRETTY GOOD AGREEMENT ON TRACKING THE UPPER LOW
SLOWLY EASTWARD TODAY. THERE WILL BE A STRONG VORT MAX/JET STREAK
COMING INTO THE CWA BY THIS AFTERNOON. WITH THE STRONG UPPER LEVEL
SYSTEM COMING THROUGH...BULK SHEAR VALUES WILL BE VERY STRONG...UP
IN THE 50 TO 60 KT RANGE ACROSS PORTIONS OF THE SOUTHERN CWA. MORE
IN QUESTION WILL BE THE INSTABILITY. THE NAM BRINGS CAPE VALUES OF
1500-2000 J/KG INTO OUR SOUTHEASTERN COUNTIES...AND THE RUC IS
SIMILAR BUT MORE IN THE 1000-1500 RANGE. STRATUS OVER THE EAST HAS
BEEN CLEARING OUT AND FOG HAS BEEN NOT VERY WIDESPREAD...SO THERE
SHOULD BE AT LEAST A LITTLE BIT OF HEATING THIS AFTERNOON.
HOWEVER...CLOUDS HAVE BEEN INCREASING OVER THE WESTERN COUNTIES
AND REGIONAL RADAR SHOWS QUITE A BIT OF ACTIVITY OVER WESTERN ND
WITH THE JET STREAK COMING OUT. THE UPPER SUPPORT MAY BE INTO THE
ARE BEFORE WE CAN DESTABILIZE ENOUGH. FOR THAT REASON...BUMPED UP
POPS AND WILL MENTION CHANCE OF SEVERE IN THE HWO...BUT WILL KEEP
A SEVERE MENTION OUT OF THE GRIDS FOR THE TIME BEING.
TONIGHT...THE MAIN UPPER LOW WILL LIFT NORTHEASTWARD INTO CANADA.
A FEW SHOWERS MAY BE HANGING AROUND THE NORTHEASTERN COUNTIES
EARLY ON BUT THINK THERE WILL BE A BREAK IN PRECIP FOR MUCH OF THE
NIGHT. CONTINUED TO KEEP TEMPS OVERNIGHT IN THE UPPER 50S TO LOW
60S. SUNSHINE AND SOUTH TO SOUTHWESTERLY SFC WINDS SHOULD HELP
HIGHS ON SATURDAY REACH THE 80S IN MANY AREAS. BY SATURDAY
AFTERNOON...A WEAK SHORTWAVE PUSHING IN FROM THE WEST WILL HELP
BRING A SFC TROUGH AXIS INTO CENTRAL ND AND THERE SHOULD BE SOME
CONVECTIVE ACTIVITY ALONG WITH IT. BULK SHEAR VALUES ARE QUITE A
BIT LOWER BUT THERE SHOULD BE DECENT INSTABILITY. WILL CONTINUE TO
KEEP CHANCE POPS GOING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUN 20 2014
SATURDAY NIGHT THROUGH SUNDAY NIGHT...MORE SHORTWAVES MOVE THROUGH
AS THE ACTIVE PATTERN CONTINUES UNDER WEST TO SOUTHWESTERLY FLOW
ALOFT. THE MAIN SFC TROUGH WILL MOVE OFF TO THE EAST SATURDAY
NIGHT INTO SUNDAY...WITH SOME WEAK COLD AIR ADVECTION BEHIND IT.
THINK THAT BEST CHANCES FOR PRECIP WILL BE LATE SATURDAY NIGHT
INTO SUNDAY AS THIS FEATURE MOVES THROUGH. KEPT 20-40 POPS GOING
BEFORE TAPERING THEM OFF SUNDAY NIGHT. TEMPS ON SUNDAY WILL BE A
BIT LOWER THAN SATURDAY...MAINLY IN THE 70S.
MONDAY THROUGH THURSDAY...THIS PERIOD WILL BE CATEGORIZED BY MEAN
ZONAL FLOW...THE UPPER LOW HAVING DEPARTED TO THE EAST. SEVERAL
SHORT WAVE RIPPLES LIKELY TO MOVE THROUGH THIS FLOW...OFFERING
PCPN CHANCES PERHAPS TUESDAY AND AGAIN ON THURSDAY. BELIEVE THE
BEST BET FOR TOTALLY DRY WILL COME MIDWEEK...AS BOTH 00Z GFS/ECMWF
DEPICT A BUBBLE OF CANADIAN HIGH PRESSURE FOR WEDNESDAY.
LOOKS LIKE WARMEST DAY WILL BE MONDAY WITH COOLER READINGS UNDER
MORE CLOUD COVER TUESDAY...RECOVERING TO NEAR AVERAGE FOR LATE JUNE
BY WED/THUR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1146 PM CDT THU JUN 19 2014
DID NOT MENTION ANY FOG SO LATER SHIFTS WILL HAVE TO ADD IF IT
APPEARS MORE LIKELY. LOOKS LIKE MID CLOUDS AND MORE SHOWERS WILL
DRIFT INTO THE WESTERN FA IN THE EARLY MORNING...DRIFTING ACROSS
THE NORTH THROUGH THE MID TO LATE MORNING. MAY BE MORE CONVECTION
DEVELOPING BY AFTERNOON THEN CLEARING BY EVENING.
&&
.HYDROLOGY...
ISSUED AT 252 PM CDT THU JUN 19 2014
RECENT HEAVY RAINS OVER THE RED RIVER BASIN IS CAUSING RISES ON
THE MAINSTEM RED RIVER AND MINNESOTA TRIBUTARIES. RAINFALL AMOUNTS
RANGED FROM 2.5 INCHES AROUND THE WAHPETON/BRECKENRIDGE AREA TO
AROUND A QUARTER INCH IN BELTRAMI AND LAKE OF THE WOODS COUNTIES.
WITH THE RAINFALL...NEW RIVER POINT WARNINGS HAVE BEEN ISSUED
RAISING ABERCROMBIE...FARGO AND OSLO TO MODERATE FLOOD STAGE.
AN AREAL FLOOD WARNING HAS BEEN ISSUED UNTIL NOON SUNDAY FOR EAST
CENTRAL BELTRAMI COUNTY. BELTRAMI COUNTY EMERGENCY MANAGEMENT
RELAYED THAT THE TAMARAC RIVER NEAR WASKISH IS WELL OUT OF ITS
BANKS. WATER IS SURROUNDING NUMEROUS HOUSES WITH A FEW ROADS WASHED
OUT...AND NUMEROUS AGRICULTURAL FIELDS ARE UNDER WATER. WATER IS
ALSO BEGINNING TO APPROACH THE BOTTOMS OF BRIDGES ALONG THE TAMARAC
RIVER. MORE WATER IS EXPECTED TO FLOW INTO THE TAMARAC RIVER...AND
THE SITUATION CONTINUES TO BE MONITORED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JR
LONG TERM...WJB
AVIATION...GODON
HYDROLOGY...HOPKINS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
325 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 325 AM CDT FRI JUN 20 2014
PRECIP CHANCES AND STRENGTH WILL BE THE MAIN FORECAST ISSUE FOR
THE SHORT TERM.
UPPER LOW CURRENTLY CENTERED ALONG THE MT/CANADIAN BORDER...AND
MODELS ARE IN PRETTY GOOD AGREEMENT ON TRACKING THE UPPER LOW
SLOWLY EASTWARD TODAY. THERE WILL BE A STRONG VORT MAX/JET STREAK
COMING INTO THE CWA BY THIS AFTERNOON. WITH THE STRONG UPPER LEVEL
SYSTEM COMING THROUGH...BULK SHEAR VALUES WILL BE VERY STRONG...UP
IN THE 50 TO 60 KT RANGE ACROSS PORTIONS OF THE SOUTHERN CWA. MORE
IN QUESTION WILL BE THE INSTABILITY. THE NAM BRINGS CAPE VALUES OF
1500-2000 J/KG INTO OUR SOUTHEASTERN COUNTIES...AND THE RUC IS
SIMILAR BUT MORE IN THE 1000-1500 RANGE. STRATUS OVER THE EAST HAS
BEEN CLEARING OUT AND FOG HAS BEEN NOT VERY WIDESPREAD...SO THERE
SHOULD BE AT LEAST A LITTLE BIT OF HEATING THIS AFTERNOON.
HOWEVER...CLOUDS HAVE BEEN INCREASING OVER THE WESTERN COUNTIES
AND REGIONAL RADAR SHOWS QUITE A BIT OF ACTIVITY OVER WESTERN ND
WITH THE JET STREAK COMING OUT. THE UPPER SUPPORT MAY BE INTO THE
ARE BEFORE WE CAN DESTABILIZE ENOUGH. FOR THAT REASON...BUMPED UP
POPS AND WILL MENTION CHANCE OF SEVERE IN THE HWO...BUT WILL KEEP
A SEVERE MENTION OUT OF THE GRIDS FOR THE TIME BEING.
TONIGHT...THE MAIN UPPER LOW WILL LIFT NORTHEASTWARD INTO CANADA.
A FEW SHOWERS MAY BE HANGING AROUND THE NORTHEASTERN COUNTIES
EARLY ON BUT THINK THERE WILL BE A BREAK IN PRECIP FOR MUCH OF THE
NIGHT. CONTINUED TO KEEP TEMPS OVERNIGHT IN THE UPPER 50S TO LOW
60S. SUNSHINE AND SOUTH TO SOUTHWESTERLY SFC WINDS SHOULD HELP
HIGHS ON SATURDAY REACH THE 80S IN MANY AREAS. BY SATURDAY
AFTERNOON...A WEAK SHORTWAVE PUSHING IN FROM THE WEST WILL HELP
BRING A SFC TROUGH AXIS INTO CENTRAL ND AND THERE SHOULD BE SOME
CONVECTIVE ACTIVITY ALONG WITH IT. BULK SHEAR VALUES ARE QUITE A
BIT LOWER BUT THERE SHOULD BE DECENT INSTABILITY. WILL CONTINUE TO
KEEP CHANCE POPS GOING.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI JUN 20 2014
SATURDAY NIGHT THROUGH SUNDAY NIGHT...MORE SHORTWAVES MOVE THROUGH
AS THE ACTIVE PATTERN CONTINUES UNDER WEST TO SOUTHWESTERLY FLOW
ALOFT. THE MAIN SFC TROUGH WILL MOVE OFF TO THE EAST SATURDAY
NIGHT INTO SUNDAY...WITH SOME WEAK COLD AIR ADVECTION BEHIND IT.
THINK THAT BEST CHANCES FOR PRECIP WILL BE LATE SATURDAY NIGHT
INTO SUNDAY AS THIS FEATURE MOVES THROUGH. KEPT 20-40 POPS GOING
BEFORE TAPERING THEM OFF SUNDAY NIGHT. TEMPS ON SUNDAY WILL BE A
BIT LOWER THAN SATURDAY...MAINLY IN THE 70S.
MONDAY THROUGH THURSDAY...THIS PERIOD WILL BE CATEGORIZED BY MEAN
ZONAL FLOW...THE UPPER LOW HAVING DEPARTED TO THE EAST. SEVERAL
SHORT WAVE RIPPLES LIKELY TO MOVE THROUGH THIS FLOW...OFFERING
PCPN CHANCES PERHAPS TUESDAY AND AGAIN ON THURSDAY. BELIEVE THE
BEST BET FOR TOTALLY DRY WILL COME MIDWEEK...AS BOTH 00Z GFS/ECMWF
DEPICT A BUBBLE OF CANADIAN HIGH PRESSURE FOR WEDNESDAY.
LOOKS LIKE WARMEST DAY WILL BE MONDAY WITH COOLER READINGS UNDER
MORE CLOUD COVER TUESDAY...RECOVERING TO NEAR AVERAGE FOR LATE JUNE
BY WED/THUR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1146 PM CDT THU JUN 19 2014
DID NOT MENTION ANY FOG SO LATER SHIFTS WILL HAVE TO ADD IF IT
APPEARS MORE LIKELY. LOOKS LIKE MID CLOUDS AND MORE SHOWERS WILL
DRIFT INTO THE WESTERN FA IN THE EARLY MORNING...DRIFTING ACROSS
THE NORTH THROUGH THE MID TO LATE MORNING. MAY BE MORE CONVECTION
DEVELOPING BY AFTERNOON THEN CLEARING BY EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JR
LONG TERM...JR/WJB
AVIATION...GODON
AREA FORECAST DISCUSSION
NWS PORTLAND OR
326 AM PDT FRI JUN 20 2014
.SYNOPSIS...COOLER WITH LOTS OF CLOUDS TODAY THEN A PATTERN OF
MORNING CLOUDS WITH AFTERNOON SUNSHINE EXPECTED FOR THE WEEKEND.
MILD WEATHER CONTINUES NEXT WEEK...BUT MAY HAVE A FEW SHOWERS ABOUT
THE AREA...MAINLY FROM OVER THE CASCADES AND POINTS EASTWARD.
&&
.SHORT TERM...TODAY THROUGH MONDAY...FRONT HELD TOGETHER LONG ENOUGH
TO BRING 0.10 TO 0.20 INCHES OF RAIN TO THE IMMEDIATE COAST WITH
LESSER AMOUNTS CLOSER TO NEWPORT. IT SHEARED APART UPON CROSSING THE
COAST RANGE AND IS NOT SOMEWHAT OF A DISJOINTED MESS OVER THE VALLEY
AND CASCADES. HAVE SQUEEZED OUT CLOSE TO A TENTH FOR THE PORTLAND
AIRPORT WHERE LOW LEVEL CONVERGENT FLOW BRIEFLY AND LOCALLY
RE-ENERGIZED THE FRONT. 06Z NAM AND THE 07Z HRRR SHOW THE FRONT WILL
CONTINUE TO DISSIPATE AS IT DRIFTS EASTWARD WITH LINGERING CASCADE
AND FOOTHILL SHOWERS THROUGH AT LEAST THE EARLY MORNING. POST
FRONTAL JET ASSISTED LIFT IS BRINGING ISOLATED SHOWER ACTIVITY OVER
THE WATERS SO HAVE ADDED THE MENTION OF SUCH FOR THE MORNING. KEPT
DRIZZLE IN THE FORECAST FOR THE MORNING INLAND AND WEST OF THE
CASCADE FOOTHILLS AS AM HAVING A HARD TIME IGNORING THE MODESTLY
DEEP MOISTURE FIELD PLUS LIFT THROUGH IT FROM THE 00Z GFS. AM HAVING
STRONG SUSPICIONS, HOWEVER, WE MAY BE OVERDOING IT GIVEN THE HIGHER
CLOUD BASES OF 3 TO 4 THOUSAND FEET FROM TILLAMOOK AND GENERALLY
POINTS NORTHWARD ALONG THE COAST. WOULD PREFER TO SEE BASES BELOW
1500 FEET TO FEEL BETTER ABOUT DRIZZLE NOT EVAPORATING BEFORE
REACHING THE SURFACE. WILL REASSESS CLOSER TO THE END OF SHIFT.
NOT MUCH CHANGE FOR THE REST OF THE FORECAST HEADING INTO MONDAY AS
THE REGION WILL SEE MORNING CLOUDS FOLLOWED BY AFTERNOON SUN OR AT
LEAST SIGNIFICANT SUN BREAKS. THIS PATTERN WILL ALSO BRING
SOME DECENTLY CONSISTENT BREEZY WEST WINDS TO THE CENTRAL GORGE AS
PERSISTENT SURFACE LOW PRESSURE WILL SET UP OVER THE COLUMBIA BASIN.
REGARDING TEMPERATURES...TODAY LOOKS TO BE TO COOLEST OF THE
UPCOMING FEW DAYS AS CLOUDS WILL MOST LIKELY HANG ON THE LONGEST.
MONDAY MAY ALSO BE A BIT TRICKY AS ANOTHER FEATURE APPROACHES THE
COAST BUT ALSO SUSPECT TIMING WILL KEEP THE PRIMARY THREAT FOR RAIN
UNTIL LATER IN THE EVENING. THIS SHOULD OFFSET TEMPERATURES COOLING
OFF MORE THAN A COUPLE DEGREES FROM SUNDAY. /JBONK
.LONG TERM...MONDAY NIGHT THROUGH THURSDAY...HAVE MADE SOME CHANGES
TO REFLECT CONTINUED UNCERTAINTY IN THE EXTENDED PERIODS. HAVE SEEN
NOTABLE INCONSISTENCY BETWEEN THE 12Z AND 00Z RUNS...NOT SO MUCH IN
THE LARGE SCALE PATTERN BUT WITH THE DETAILS REGARDING MOISTURE AND
SHORTWAVE TIMING. THE UPPER TROUGH SITTING SOMEWHAT OFF THE PACNW
COAST FREQUENTLY PROVES PROBLEMATIC FOR MODELS AND KEEPING TRACK OF
THE IMPORTANT FEATURES WHICH BRING THE DETAILS BETTER INTO FOCUS.
MAIN CONCERN IS WHICH DAYS APPEAR TO BE MOST LIKELY FOR
AFTERNOON/EVENING SHOWERS. AT THIS POINT...DO NOT HAVE OVERWHELMING
CONFIDENCE TO GO WHOLE HOG EITHER WAY FOR THE MAJORITY OF THE
PERIODS. AM KEEPING AN EYE OUT FOR WEDNESDAY NIGHT AND
THURSDAY...HOWEVER...AS ONE SHORTWAVE MAY STRENGTHEN ENOUGH TO PUSH
A NEGATIVE TILT TO THE TROUGH AS IT PASSES. THIS PATTERN OFTEN
SIGNALS A THUNDERSTORM THREAT. FOR NOW...TIMING PRESENTS THE BEST
DYNAMIC SUPPORT FOR THUNDERSTORMS JUST EAST OF THE CASCADE CREST BUT
WILL BE WATCHING. /JBONK
&&
.AVIATION...FAIRLY NARROW NORTH-SOUTH ORIENTED FRONT MOVING ACROSS
THE INTERIOR LOWLANDS AT 10Z AND SHOULD BE IN THE CASCADES BY 12Z.
AREAS OF MVFR EXPECTED WITH THE FRONT FOLLOWED BY VFR CONDITIONS
AS A DRIER...MORE UNSTABLE AIR MASS MOVES INTO THE AREA. GENERALLY
SHOULD SEE VFR FOR MOST AREAS BY 13Z-15Z. VFR CONDITIONS ARE THEN
EXPECTED THROUGH 12Z SATURDAY.
KPDX AND APPROACHES...MVFR CIGS AROUND 2500 FT IN THE AREA AS THE
FRONT MOVES INTO THE CASCADES.
&&
.MARINE...HIGH PRES RETURNS TO THE WATERS THIS MORNING BEHIND A
WEAK COLD FRONT. WINDS ARE STILL A LITTLE GUSTY BUT REMAIN BELOW
ADVISORY CRITERIA. FOR THE REMAINDER OF THE WEEKEND AND INTO EARLY
NEXT WEEK NORTHERLY WINDS MAY OCCASIONALLY GUST TO AROUND 20 KT
DURING THE AFTERNOON AND EARLY EVENING...PARTICULARLY FOR THE
WATERS SOUTH OF CASCADE HEAD.
SEAS SHOULD REMAIN IN THE 6 TO 8 FT RANGE TODAY THEN SETTLE TO
AROUND 5 FT SAT AND INTO EARLY NEXT WEEK.
OTHERWISE...A COUPLE WEEK FRONTAL SYSTEMS WILL TRACK ACROSS THE
WATERS EARLY NEXT WEEK...BUT NO MAJOR WIND OR SEA ISSUES APPEAR IN
STORE. /NEUMAN/MH
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
445 PM EDT FRI JUN 20 2014
.SYNOPSIS...
AN UPPER RIDGE WILL CONTINUE TO BREAK DOWN THROUGH THIS EVENING
RESULTING IN WEAKENING HIGH PRESSURE CURRENTLY IN PLACE OVER THE
AREA. THIS SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS THE AREA OVER THE WEEKEND AND INTO EARLY NEXT
WEEK. A TYPICAL WARM SUMMERLIKE PATTERN WILL CONTINUE THROUGH NEXT
WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
430 PM EDT UPDATE...LOW SFC TD/S AND A NOTABLE LOBE OF DNVA HAS KEPT
CONVECTION MINIMAL AND RELATIVELY SHORT LIVED ACROSS CWFA THUS FAR
THIS AFTERNOON. THE STORMS TO THE EAST HAVE BEEN ABLE TO TAP INTO
HIGH VALUES OF DCAPE AND PRODUCE SEVERE WINDS...BUT THE REMAINING
CELLS HAVE HAD FAIRLY NARROW AND WEAKER UPDRAFTS. THE NAM12 HAS A
GOOD HANDLE ON THE UPPER VORT FIELD AND WILL FOLLOW IT/S GUIDANCE
WRT TO POPS AND CONVEC INITIATION OVER THE NEXT COUPLE HRS. THE
UPSTATE HAS THE LOWEST INSTABILITY COMBINED WITH NEGATIVE ULVL
FORCING...SO POPS WILL BE LOWERED TO ISOL THERE...ACROSS THE SRN NC
FTHILLS. THE BEST CHANCE FOR NEW DEVELOPMENT WILL BE ACROSS THE NC
MTN SPINE WHERE ENHANCED CONVECTION SHOULD MOVE IN AND LIKELY WEAKEN
THROUGH 8 PM.
AS OF 200 PM EDT...CELLS NOW LINING UP ALONG THE BLUE RIDGE AS A
WEAK RIPPLE ROUNDS THE RIDGE OVER THE LOWER MISSISSIPPI VALLEY AND
MOVES SEWD ACRS THE AREA. HRRR SEEMS TO HAVE PICKED UP ON THIS
ACTIVITY AND ALLOWS IT TO PROPAGATE SEWD SLIGHTLY BEFORE
DISSIPATING...POSSIBLY DUE TO DOWNSLOPING BY THE NW FLOW ABOVE THE
BOUNDARY LAYER. THE NCEP HIRES WINDOW /NMM/ SUGGESTS THE SAME...BUT
DEVELOPS A NEW ROUND OF CONVECTION IN THE MTNS BEHIND IT WHICH FILLS
IN THE SAME AREA. DEWPOINTS HAVE MIXED OUT SLIGHTLY AS
EXPECTED...BUT NOT ENOUGH TO KEEP SBCAPE FROM RISING TO 2000 J OR
MORE PER SPC MESOANALYSIS. NO SEVERE REPORTS HAVE YET BEEN RECEIVED
BUT A FEW STORMS HAVE MET WARNING CRITERIA. I AM NO LONGER CONFIDENT
IN OUR EARLIER EXPECTATIONS THAT WE WOULD NOT GET UNSTABLE ENOUGH
FOR LARGE HAIL TO BE MUCH OF A CONCERN...BUT PROFILES REMAIN DRY
ENOUGH FOR DCAPES OF 700-1000 J SUPPORTING A MICROBURST THREAT. CHC
RANGE POPS HAVE BEEN MAINTAINED ACRS MOST OF THE AREA...BUT NOW THE
GREATEST CHANCE APPEARS TO BE DOWNSTREAM OF THE CURRENT ACTIVITY.
SOME MODELS INCLUDING THE NAM TRY TO DEVELOP ANOTHER ROUND OF
CONVECTION AFTER SUNSET...BUT PROFILES HAVE ENOUGH CIN THAT I THINK
THIS IS UNLIKELY IN THE PRESENCE OF SUCH WEAK FORCING. POPS DIMINISH
EAST OF THE MTNS BY LATE EVENING.
MAIN FORECAST CHALLENGE FOR THE OVERNIGHT IS WHETHER ANY ACTIVITY
WILL MOVE INTO OUR AREA FROM THE WEST...AS SUGGESTED BY SOME OF THE
MESO GUIDANCE AND THE 12Z NAM. THE NAM SHOWS AN MCV DEVELOPING OVER
THE OHIO VALLEY LATE THIS AFTN AND PROGRESSING SEWD ACRS KY/TN...THE
ORIGINAL CONVECTION DYING BUT THE MCV KICKING OFF NEW DEVELOPMENT ON
THE WEST SLOPES OF THE MTNS WHICH THEN MOVES INTO NW NC AROUND
DAYBREAK. SO FAR THE NAM DEPICTION OF THE ORIGINATING CONVECTION
SEEMS OVERDONE...SO WILL ONLY GIVE THIS SMALL WEIGHT IN THE FCST.
CLOUD COVER PROGGED BY THE MODELS APPEARS MAINLY TO BE CONVECTIVE
DEBRIS AND IT IS A BIT HARDER TO HEDGE ON THAT.
THE NAM SUGGESTS DEEP RH WILL BE HIGHER ON SATURDAY...PROBABLY SINCE
IT EXPECTS DEBRIS TO COME IN DURING THE MORNING. GFS PROFILES REALLY
DO NOT LOOK TOO MUCH DIFFERENT FROM TODAY...THOUGH SBCAPE IS STILL
LOWER DUE TO SLIGHTLY WEAKER LAPSE RATES. THE DIFFERENCE IS NOT ONLY
IMPORTANT FOR THE POTENTIALLY SIGNIFICANT REDUCTION IN INSTABILITY
DUE TO CLOUDIER SKIES...BUT FOR A REDUCTION IN DCAPE AND MITIGATED
SEVERE RISK. SPC FEATURES A 5 PCT AREA JUST TO OUR EAST WHERE WEAK
SHORTWAVE /THE POTENTIAL MCV/ WILL PASS OVER DURING PEAK HEATING. IT
DOES APPEAR THE BEST PRECIP CHANCES OVERALL WILL BE DURING THE
MORNING IN THE NORTHERN FA AND THEN OVER THE I-77 CORRIDOR DURING
THE AFTN WHERE THE BEST BUOYANCY IS SUGGESTED. TEMPS TONIGHT AND
TOMORROW WILL REMAIN A CATEGORY OR SO ABOVE CLIMO.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM FRIDAY...HEIGHTS WILL GRADUALLY FALL THROUGH EARLY NEXT
WEEK...AS UPPER HIGH CONTINUES TO WEAKEN AND RETROGRADE TOWARDS
THE WESTERN GULF OF MEXICO. THIS WILL ALSO ALLOW WEAK FRONTAL ZONE
TO BACK DOOR ITS WAY THROUGH THE AREA BY SUNDAY...POSSIBLY
INTRODUCING SLIGHTLY COOLER AND DRIER AIR. THIS IS NOT EXPECTED TO
ELIMINATE INSTABILITY ENOUGH TO HALT DIURNAL CONVECTION...BUT
COVERAGE OF SUNDAY AFTERNOON/EVENING CONVECTION IS EXPECTED TO BE
MORE TYPICAL OF WHAT ONE WOULD EXPECT THIS TIME OF YEAR (30-40 POPS
MTNS...20/30 PIEDMONT).
BY MONDAY... SHORT TERM MODELS DEPICT ESTABLISHMENT OF AN E/SE FLOW
IN ASSOCIATION WITH A WEAK INVERTED RIDGE ALONG THE EASTERN
SEABOARD. THIS UPSLOPE FLOW COULD SUPPORT A BIT MORE IN THE WAY OF
DIURNAL CONVECTION BY MONDAY AFTERNOON...SO POPS RETURN TO ABOVE
CLIMO BY THIS TIME. WEAK SHEAR WITH HALFWAY DECENT STEERING FLOW
SHOULD PRECLUDE ANYTHING MORE THAN A TYPICAL EARLY SUMMER PULSE
SEVERE THREAT OR FLASH FLOODING THREAT SUNDAY. HOWEVER...HEAVY
RAINFALL MAY BECOME AN ISSUE MONDAY...AS UPPER FLOW WEAKENS ABOVE
THE LOW LEVEL SOUTHEAST FLOW...POSSIBLY FAVORING ANCHORING OF CELLS
ACROSS PORTIONS OF THE HIGH TERRAIN. TEMPS ARE EXPECTED TO RETURN TO
NEAR CLIMO BY MONDAY IN THE RELATIVELY COOL E/SE FLOW
REGIME.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 130 PM EDT FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
TUESDAY WITH WEAK UPPER RIDGING OVER THE SE CONUS AND A LOW
AMPLITUDE UPPER TROF DIGGING DOWN OVER OVER THE DAKOTAS AND
MINNESOTA. OVER THE NEXT FEW DAYS...THE TROF SLOWLY PROPAGATES
EASTWARD...YET IT DOES NOT APPEAR TO MAKE MUCH HEADWAY SOUTHWARD.
THE LONG RANGE MODELS HAVE BEEN DIFFERING A FAIR AMOUNT WRT THE
AMPLIFICATION OF THIS TROF...BUT ITS LOOKING LIKE THEY ARE LEANING
MORE TOWARDS STRONGER RIDGING OVER OUR FCST AREA THRU DAY 7. THIS PATTERN
LEAVES OUR AREA UNDER GENERALLY WEAK WEST TO SWLY STEERING FLOW THRU
THE PERIOD. AT THE SFC...THE REGION WILL BE UNDER THE INFLUENCE OF
THE BERMUDA HIGH FOR MOST OF THE PERIOD WITH A COLD FRONT
APPROACHING THE CAROLINAS BY EARLY WED AND WASHING OUT AS IT MOVES
OVER THE CWFA. IN ITS WAKE...WEAK CANADIAN HIGH PRESSURE TRIES TO
PUSH SOUTHWARD FROM NEW ENGLAND BUT ITS PROGRESS IS SUPPRESSED BY
THE BERMUDA HIGH. WITH THE COMBINATION OF SLY MOIST FLOW...A WEAKLY
SHEARED ENVIRONMENT AND MODERATE DIURNAL BUOYANCY...WE STILL HAVE A
SOLID CHANCE OF PULSE TYPE CONVECTION ACROSS MUCH OF THE REGION EACH
DAY...FAVORING IN THE MTN ZONES OVERALL. TEMPERATURES SHOULD REMAIN
FAIRLY STEADY WITH VALUES NEAR NORMAL OR POSSIBLE A FEW DEGREES
WARMER.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
AT KCLT...SOME QUESTION WHETHER TSRA WILL BE ABLE TO FORM EARLY THIS
AFTN. CLUSTER OF CELLS NEAR THE BLUE RIDGE AT 1745Z IS SLOWLY MOVING
SEWD TOWARD THE FIELD. OUTFLOW FROM THESE CELLS COULD REACH THE
FIELD 20-21Z BUT MIGHT KICK NEW ACTIVITY OFF BEFOREHAND. INCLUDED A
TEMPO MVFR TSRA WHEN CHANCES LOOK GREATEST OVERALL PER MESO MODELS
AND THE TIMING OF A WEAK SHORTWAVE PASSING THRU. BRISK GUSTS
POSSIBLE WITH ANY TSRA. SOME CONVECTIVE DEBRIS FORMING A VFR CIG MAY
LINGER OVERNIGHT IF TSRA CLUSTERS FORM UPSTREAM AS SUGGESTED BY
GUIDANCE. MRNG RESTRICTIONS ARE NOT OUT OF THE QUESTION IF A TSRA
DOES AFFECT THE FIELD THIS AFTN...ESP IF SAID DEBRIS DOES NOT FORM
AND RADIATION IS MAXIMIZED UNDER LIGHT FLOW REGIME. DIURNAL CU WILL
LIKELY FORM A BIT LOWER SATURDAY BUT STILL VFR. WINDS PREVAILING
NWLY INTO SAT MRNG BUT THEN WILL BACK TO A NEAR CROSSWIND AS LEE
TROUGH DEVELOPS.
ELSEWHERE...CONVECTIVE CHANCES THIS AFTN ARE OVERALL NOT AS HIGH AS
THE PAST COUPLE OF DAYS...BUT STILL WARRANTS A MENTION AT ALL SITES
EXCEPT KAND. BEST CHANCES ARE ACTUALLY EAST OF THE BLUE RIDGE IN THE
VICINITY OF A SMALL SHORTWAVE THAT WILL MOVE SEWD ACRS THE PIEDMONT
THIS AFTN. GUSTY WINDS OF 20-25 KT AND BRIEF MVFR VSBY COULD OCCUR
WITH ANY TSRA. EXCEPT IN THE VCNTY OF TSRA...NW TO W WINDS WILL
PREVAIL THOUGH SOME VARIABILITY IS LIKELY GIVEN THE WEAK FLOW. MTN
VALLEY FOG LIKELY AGAIN TONIGHT AND RAINFALL THIS AFTN WILL ENHANCE
THE FOG POTENTIAL AS USUAL. NW TO WNW WINDS PREVAIL SAT WITH LEE
TROUGH TO THE E.
OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
ARE EXPECTED INTO THE WEEKEND...WITH THE GREATEST COVERAGE ACROSS
THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN
VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF
RECENT RAINFALL.
CONFIDENCE TABLE...
20-02Z 02-08Z 08-14Z 14-20Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 95% HIGH 100% HIGH 84%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...STAARMANN
NEAR TERM...SBK/WIMBERLEY
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
243 PM EDT FRI JUN 20 2014
.SYNOPSIS...
AN UPPER RIDGE WILL CONTINUE TO BREAK DOWN THROUGH THIS EVENING
RESULTING IN WEAKENING HIGH PRESSURE CURRENTLY IN PLACE OVER THE
AREA. THIS SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS THE AREA OVER THE WEEKEND AND INTO EARLY NEXT
WEEK. A TYPICAL WARM SUMMERLIKE PATTERN WILL CONTINUE THROUGH NEXT
WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 200 PM EDT...CELLS NOW LINING UP ALONG THE BLUE RIDGE AS A
WEAK RIPPLE ROUNDS THE RIDGE OVER THE LOWER MISSISSIPPI VALLEY AND
MOVES SEWD ACRS THE AREA. HRRR SEEMS TO HAVE PICKED UP ON THIS
ACTIVITY AND ALLOWS IT TO PROPAGATE SEWD SLIGHTLY BEFORE
DISSIPATING...POSSIBLY DUE TO DOWNSLOPING BY THE NW FLOW ABOVE THE
BOUNDARY LAYER. THE NCEP HIRES WINDOW /NMM/ SUGGESTS THE SAME...BUT
DEVELOPS A NEW ROUND OF CONVECTION IN THE MTNS BEHIND IT WHICH FILLS
IN THE SAME AREA. DEWPOINTS HAVE MIXED OUT SLIGHTLY AS
EXPECTED...BUT NOT ENOUGH TO KEEP SBCAPE FROM RISING TO 2000 J OR
MORE PER SPC MESOANALYSIS. NO SEVERE REPORTS HAVE YET BEEN RECEIVED
BUT A FEW STORMS HAVE MET WARNING CRITERIA. I AM NO LONGER CONFIDENT
IN OUR EARLIER EXPECTATIONS THAT WE WOULD NOT GET UNSTABLE ENOUGH
FOR LARGE HAIL TO BE MUCH OF A CONCERN...BUT PROFILES REMAIN DRY
ENOUGH FOR DCAPES OF 700-1000 J SUPPORTING A MICROBURST THREAT. CHC
RANGE POPS HAVE BEEN MAINTAINED ACRS MOST OF THE AREA...BUT NOW THE
GREATEST CHANCE APPEARS TO BE DOWNSTREAM OF THE CURRENT ACTIVITY.
SOME MODELS INCLUDING THE NAM TRY TO DEVELOP ANOTHER ROUND OF
CONVECTION AFTER SUNSET...BUT PROFILES HAVE ENOUGH CIN THAT I THINK
THIS IS UNLIKELY IN THE PRESENCE OF SUCH WEAK FORCING. POPS DIMINISH
EAST OF THE MTNS BY LATE EVENING.
MAIN FORECAST CHALLENGE FOR THE OVERNIGHT IS WHETHER ANY ACTIVITY
WILL MOVE INTO OUR AREA FROM THE WEST...AS SUGGESTED BY SOME OF THE
MESO GUIDANCE AND THE 12Z NAM. THE NAM SHOWS AN MCV DEVELOPING OVER
THE OHIO VALLEY LATE THIS AFTN AND PROGRESSING SEWD ACRS KY/TN...THE
ORIGINAL CONVECTION DYING BUT THE MCV KICKING OFF NEW DEVELOPMENT ON
THE WEST SLOPES OF THE MTNS WHICH THEN MOVES INTO NW NC AROUND
DAYBREAK. SO FAR THE NAM DEPICTION OF THE ORIGINATING CONVECTION
SEEMS OVERDONE...SO WILL ONLY GIVE THIS SMALL WEIGHT IN THE FCST.
CLOUD COVER PROGGED BY THE MODELS APPEARS MAINLY TO BE CONVECTIVE
DEBRIS AND IT IS A BIT HARDER TO HEDGE ON THAT.
THE NAM SUGGESTS DEEP RH WILL BE HIGHER ON SATURDAY...PROBABLY SINCE
IT EXPECTS DEBRIS TO COME IN DURING THE MORNING. GFS PROFILES REALLY
DO NOT LOOK TOO MUCH DIFFERENT FROM TODAY...THOUGH SBCAPE IS STILL
LOWER DUE TO SLIGHTLY WEAKER LAPSE RATES. THE DIFFERENCE IS NOT ONLY
IMPORTANT FOR THE POTENTIALLY SIGNIFICANT REDUCTION IN INSTABILITY
DUE TO CLOUDIER SKIES...BUT FOR A REDUCTION IN DCAPE AND MITIGATED
SEVERE RISK. SPC FEATURES A 5 PCT AREA JUST TO OUR EAST WHERE WEAK
SHORTWAVE /THE POTENTIAL MCV/ WILL PASS OVER DURING PEAK HEATING. IT
DOES APPEAR THE BEST PRECIP CHANCES OVERALL WILL BE DURING THE
MORNING IN THE NORTHERN FA AND THEN OVER THE I-77 CORRIDOR DURING
THE AFTN WHERE THE BEST BUOYANCY IS SUGGESTED. TEMPS TONIGHT AND
TOMORROW WILL REMAIN A CATEGORY OR SO ABOVE CLIMO.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM FRIDAY...HEIGHTS WILL GRADUALLY FALL THROUGH EARLY NEXT
WEEK...AS UPPER HIGH CONTINUES TO WEAKEN AND RETROGRADE TOWARDS
THE WESTERN GULF OF MEXICO. THIS WILL ALSO ALLOW WEAK FRONTAL ZONE
TO BACK DOOR ITS WAY THROUGH THE AREA BY SUNDAY...POSSIBLY
INTRODUCING SLIGHTLY COOLER AND DRIER AIR. THIS IS NOT EXPECTED TO
ELIMINATE INSTABILITY ENOUGH TO HALT DIURNAL CONVECTION...BUT
COVERAGE OF SUNDAY AFTERNOON/EVENING CONVECTION IS EXPECTED TO BE
MORE TYPICAL OF WHAT ONE WOULD EXPECT THIS TIME OF YEAR (30-40 POPS
MTNS...20/30 PIEDMONT).
BY MONDAY... SHORT TERM MODELS DEPICT ESTABLISHMENT OF AN E/SE FLOW
IN ASSOCIATION WITH A WEAK INVERTED RIDGE ALONG THE EASTERN
SEABOARD. THIS UPSLOPE FLOW COULD SUPPORT A BIT MORE IN THE WAY OF
DIURNAL CONVECTION BY MONDAY AFTERNOON...SO POPS RETURN TO ABOVE
CLIMO BY THIS TIME. WEAK SHEAR WITH HALFWAY DECENT STEERING FLOW
SHOULD PRECLUDE ANYTHING MORE THAN A TYPICAL EARLY SUMMER PULSE
SEVERE THREAT OR FLASH FLOODING THREAT SUNDAY. HOWEVER...HEAVY
RAINFALL MAY BECOME AN ISSUE MONDAY...AS UPPER FLOW WEAKENS ABOVE
THE LOW LEVEL SOUTHEAST FLOW...POSSIBLY FAVORING ANCHORING OF CELLS
ACROSS PORTIONS OF THE HIGH TERRAIN. TEMPS ARE EXPECTED TO RETURN TO
NEAR CLIMO BY MONDAY IN THE RELATIVELY COOL E/SE FLOW
REGIME.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 130 PM EDT FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
TUESDAY WITH WEAK UPPER RIDGING OVER THE SE CONUS AND A LOW
AMPLITUDE UPPER TROF DIGGING DOWN OVER OVER THE DAKOTAS AND
MINNESOTA. OVER THE NEXT FEW DAYS...THE TROF SLOWLY PROPAGATES
EASTWARD...YET IT DOES NOT APPEAR TO MAKE MUCH HEADWAY SOUTHWARD.
THE LONG RANGE MODELS HAVE BEEN DIFFERING A FAIR AMOUNT WRT THE
AMPLIFICATION OF THIS TROF...BUT ITS LOOKING LIKE THEY ARE LEANING
MORE TOWARDS STRONGER RIDGING OVER OUR FCST AREA THRU DAY 7. THIS PATTERN
LEAVES OUR AREA UNDER GENERALLY WEAK WEST TO SWLY STEERING FLOW THRU
THE PERIOD. AT THE SFC...THE REGION WILL BE UNDER THE INFLUENCE OF
THE BERMUDA HIGH FOR MOST OF THE PERIOD WITH A COLD FRONT
APPROACHING THE CAROLINAS BY EARLY WED AND WASHING OUT AS IT MOVES
OVER THE CWFA. IN ITS WAKE...WEAK CANADIAN HIGH PRESSURE TRIES TO
PUSH SOUTHWARD FROM NEW ENGLAND BUT ITS PROGRESS IS SUPPRESSED BY
THE BERMUDA HIGH. WITH THE COMBINATION OF SLY MOIST FLOW...A WEAKLY
SHEARED ENVIRONMENT AND MODERATE DIURNAL BUOYANCY...WE STILL HAVE A
SOLID CHANCE OF PULSE TYPE CONVECTION ACROSS MUCH OF THE REGION EACH
DAY...FAVORING IN THE MTN ZONES OVERALL. TEMPERATURES SHOULD REMAIN
FAIRLY STEADY WITH VALUES NEAR NORMAL OR POSSIBLE A FEW DEGREES
WARMER.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
AT KCLT...SOME QUESTION WHETHER TSRA WILL BE ABLE TO FORM EARLY THIS
AFTN. CLUSTER OF CELLS NEAR THE BLUE RIDGE AT 1745Z IS SLOWLY MOVING
SEWD TOWARD THE FIELD. OUTFLOW FROM THESE CELLS COULD REACH THE
FIELD 20-21Z BUT MIGHT KICK NEW ACTIVITY OFF BEFOREHAND. INCLUDED A
TEMPO MVFR TSRA WHEN CHANCES LOOK GREATEST OVERALL PER MESO MODELS
AND THE TIMING OF A WEAK SHORTWAVE PASSING THRU. BRISK GUSTS
POSSIBLE WITH ANY TSRA. SOME CONVECTIVE DEBRIS FORMING A VFR CIG MAY
LINGER OVERNIGHT IF TSRA CLUSTERS FORM UPSTREAM AS SUGGESTED BY
GUIDANCE. MRNG RESTRICTIONS ARE NOT OUT OF THE QUESTION IF A TSRA
DOES AFFECT THE FIELD THIS AFTN...ESP IF SAID DEBRIS DOES NOT FORM
AND RADIATION IS MAXIMIZED UNDER LIGHT FLOW REGIME. DIURNAL CU WILL
LIKELY FORM A BIT LOWER SATURDAY BUT STILL VFR. WINDS PREVAILING
NWLY INTO SAT MRNG BUT THEN WILL BACK TO A NEAR CROSSWIND AS LEE
TROUGH DEVELOPS.
ELSEWHERE...CONVECTIVE CHANCES THIS AFTN ARE OVERALL NOT AS HIGH AS
THE PAST COUPLE OF DAYS...BUT STILL WARRANTS A MENTION AT ALL SITES
EXCEPT KAND. BEST CHANCES ARE ACTUALLY EAST OF THE BLUE RIDGE IN THE
VICINITY OF A SMALL SHORTWAVE THAT WILL MOVE SEWD ACRS THE PIEDMONT
THIS AFTN. GUSTY WINDS OF 20-25 KT AND BRIEF MVFR VSBY COULD OCCUR
WITH ANY TSRA. EXCEPT IN THE VCNTY OF TSRA...NW TO W WINDS WILL
PREVAIL THOUGH SOME VARIABILITY IS LIKELY GIVEN THE WEAK FLOW. MTN
VALLEY FOG LIKELY AGAIN TONIGHT AND RAINFALL THIS AFTN WILL ENHANCE
THE FOG POTENTIAL AS USUAL. NW TO WNW WINDS PREVAIL SAT WITH LEE
TROUGH TO THE E.
OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
ARE EXPECTED INTO THE WEEKEND...WITH THE GREATEST COVERAGE ACROSS
THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN
VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF
RECENT RAINFALL.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 88% HIGH 87%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...STAARMANN
NEAR TERM...WIMBERLEY
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
213 PM EDT FRI JUN 20 2014
.SYNOPSIS...
AN UPPER RIDGE WILL CONTINUE TO BREAK DOWN THROUGH THIS EVENING
RESULTING IN WEAKENING HIGH PRESSURE CURRENTLY IN PLACE OVER THE
AREA. THIS SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS THE AREA OVER THE WEEKEND AND INTO EARLY NEXT
WEEK. A TYPICAL WARM SUMMERLIKE PATTERN WILL CONTINUE THROUGH NEXT
WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 200 PM EDT...CELLS NOW LINING UP ALONG THE BLUE RIDGE AS A
WEAK RIPPLE ROUNDS THE RIDGE OVER THE LOWER MISSISSIPPI VALLEY AND
MOVES SEWD ACRS THE AREA. HRRR SEEMS TO HAVE PICKED UP ON THIS
ACTIVITY AND ALLOWS IT TO PROPAGATE SEWD SLIGHTLY BEFORE
DISSIPATING...POSSIBLY DUE TO DOWNSLOPING BY THE NW FLOW ABOVE THE
BOUNDARY LAYER. THE NCEP HIRES WINDOW /NMM/ SUGGESTS THE SAME...BUT
DEVELOPS A NEW ROUND OF CONVECTION IN THE MTNS BEHIND IT WHICH FILLS
IN THE SAME AREA. DEWPOINTS HAVE MIXED OUT SLIGHTLY AS
EXPECTED...BUT NOT ENOUGH TO KEEP SBCAPE FROM RISING TO 2000 J OR
MORE PER SPC MESOANALYSIS. NO SEVERE REPORTS HAVE YET BEEN RECEIVED
BUT A FEW STORMS HAVE MET WARNING CRITERIA. I AM NO LONGER CONFIDENT
IN OUR EARLIER EXPECTATIONS THAT WE WOULD NOT GET UNSTABLE ENOUGH
FOR LARGE HAIL TO BE MUCH OF A CONCERN...BUT PROFILES REMAIN DRY
ENOUGH FOR DCAPES OF 700-1000 J SUPPORTING A MICROBURST THREAT. CHC
RANGE POPS HAVE BEEN MAINTAINED ACRS MOST OF THE AREA...BUT NOW THE
GREATEST CHANCE APPEARS TO BE DOWNSTREAM OF THE CURRENT ACTIVITY.
SOME MODELS INCLUDING THE NAM TRY TO DEVELOP ANOTHER ROUND OF
CONVECTION AFTER SUNSET...BUT PROFILES HAVE ENOUGH CIN THAT I THINK
THIS IS UNLIKELY IN THE PRESENCE OF SUCH WEAK FORCING. POPS DIMINISH
EAST OF THE MTNS BY LATE EVENING.
MAIN FORECAST CHALLENGE FOR THE OVERNIGHT IS WHETHER ANY ACTIVITY
WILL MOVE INTO OUR AREA FROM THE WEST...AS SUGGESTED BY SOME OF THE
MESO GUIDANCE AND THE 12Z NAM. THE NAM SHOWS AN MCV DEVELOPING OVER
THE OHIO VALLEY LATE THIS AFTN AND PROGRESSING SEWD ACRS KY/TN...THE
ORIGINAL CONVECTION DYING BUT THE MCV KICKING OFF NEW DEVELOPMENT ON
THE WEST SLOPES OF THE MTNS WHICH THEN MOVES INTO NW NC AROUND
DAYBREAK. SO FAR THE NAM DEPICTION OF THE ORIGINATING CONVECTION
SEEMS OVERDONE...SO WILL ONLY GIVE THIS SMALL WEIGHT IN THE FCST.
CLOUD COVER PROGGED BY THE MODELS APPEARS MAINLY TO BE CONVECTIVE
DEBRIS AND IT IS A BIT HARDER TO HEDGE ON THAT.
MORE DETAILS ON THE NEAR TERM TO COME SHORTLY.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 230 AM FRIDAY...MODELS CONTINUE TO INDICATE THAT H5 HEIGHTS
WILL SLOWLY FALL ACROSS THE REGION SAT/SUN AS AN UPPER H5 HIGH
RETROGRADES TOWARD THE SOUTH CENTRAL STATES AND AN UPPER TROUGH
ROTATES OFF THE NE COAST. A SERIES OF UPPER IMPULSES WILL TRIGGER
MCS/MCC OVER THE OHIO VALLEY FRI NIGHT AND PROPAGATE TOWARD THE
NORTHERN NC PIEDMONT THRU EARLY SAT. HOWEVER...WITH THE LOSS OF
HEATING/CAPE OVERNIGHT...THIS SYSTEM SHOULD WEAKEN CONSIDERABLY AS
IT PASSES JUST TO OUR NORTH. HENCE...HAVE INHERITED LOW END CHANCE
POPS MAINLY IN THE NORTHERN ZONES SAT MORNING. FOR SAT AFTERNOON...A
BACK DOOR FRONTAL BOUNDARY WILL PUSH SOUTH...WITH SHOWERS AND
THUNDERSTORMS DEVELOPING ALONG THE FRONT MAINLY IN THE NC PIEDMONT
ZONES. THE NAM/GFS KEEPS THE CONDITIONS RELATIVELY DRY IN THE
MTN/UPSTATE SC GIVEN MUCH DRIER PROFILE IN PREDOMINANT N/NW FLOW
ALOFT. WITH THE HELP OF DOWNSLOPING WINDS...TEMPERATURES WILL BE
AROUND 3-5 DEGREES ABOVE NORMAL OVER THE PIEDMONT WITH NEAR NORMAL
IN THE MTNS.
SUN...HIGH PRESSURE CENTERED OVER THE NE WILL NOSE DOWN INTO THE
REGION...WITH ANOTHER ROUND OF MCS/MCC DEVELOPING OVER IN THE
VICINITY OF KY/OHIO VALLEY...PROPAGATING SOUTHWARD TOWARD THE
SOUTHERN APPALACHIANS SUN AFTERNOON. THIS FEATURE WILL REACH THE TN
BORDERLINE AROUND 21Z SUN PER LATEST NAM AND WEAKENS CONSIDERABLY
(THE NAM TOTALLY DRIES OUT) AS IT MOVES ACROSS EAST OF THE MTNS.
THIS IS DUE TO THE PREVAILING N/NW DOWNSLOPE WINDS YIELDING MUCH
DRIER PROFILE/STABLE ENVIRONMENT OVER THE PIEDMONT. HENCE...POPS
REMAIN IN THE SLIGHT CHANCE/LOW CHANCE RANGE ACROSS MUCH OF THE
REGION...WITH BETTER CHANCE IN THE MTN ZONES. TEMPERATURES WILL COOL
DOWN BY 2-3 DEGREES ON SUN.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 130 PM EDT FRIDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
TUESDAY WITH WEAK UPPER RIDGING OVER THE SE CONUS AND A LOW
AMPLITUDE UPPER TROF DIGGING DOWN OVER OVER THE DAKOTAS AND
MINNESOTA. OVER THE NEXT FEW DAYS...THE TROF SLOWLY PROPAGATES
EASTWARD...YET IT DOES NOT APPEAR TO MAKE MUCH HEADWAY SOUTHWARD.
THE LONG RANGE MODELS HAVE BEEN DIFFERING A FAIR AMOUNT WRT THE
AMPLIFICATION OF THIS TROF...BUT ITS LOOKING LIKE THEY ARE LEANING
MORE TOWARDS STRONGER RIDGING OVER OUR FCST AREA THRU DAY 7. THIS PATTERN
LEAVES OUR AREA UNDER GENERALLY WEAK WEST TO SWLY STEERING FLOW THRU
THE PERIOD. AT THE SFC...THE REGION WILL BE UNDER THE INFLUENCE OF
THE BERMUDA HIGH FOR MOST OF THE PERIOD WITH A COLD FRONT
APPROACHING THE CAROLINAS BY EARLY WED AND WASHING OUT AS IT MOVES
OVER THE CWFA. IN ITS WAKE...WEAK CANADIAN HIGH PRESSURE TRIES TO
PUSH SOUTHWARD FROM NEW ENGLAND BUT ITS PROGRESS IS SUPPRESSED BY
THE BERMUDA HIGH. WITH THE COMBINATION OF SLY MOIST FLOW...A WEAKLY
SHEARED ENVIRONMENT AND MODERATE DIURNAL BUOYANCY...WE STILL HAVE A
SOLID CHANCE OF PULSE TYPE CONVECTION ACROSS MUCH OF THE REGION EACH
DAY...FAVORING IN THE MTN ZONES OVERALL. TEMPERATURES SHOULD REMAIN
FAIRLY STEADY WITH VALUES NEAR NORMAL OR POSSIBLE A FEW DEGREES
WARMER.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AT KCLT...SOME QUESTION WHETHER TSRA WILL BE ABLE TO FORM EARLY THIS
AFTN. CLUSTER OF CELLS NEAR THE BLUE RIDGE AT 1745Z IS SLOWLY MOVING
SEWD TOWARD THE FIELD. OUTFLOW FROM THESE CELLS COULD REACH THE
FIELD 20-21Z BUT MIGHT KICK NEW ACTIVITY OFF BEFOREHAND. INCLUDED A
TEMPO MVFR TSRA WHEN CHANCES LOOK GREATEST OVERALL PER MESO MODELS
AND THE TIMING OF A WEAK SHORTWAVE PASSING THRU. BRISK GUSTS
POSSIBLE WITH ANY TSRA. SOME CONVECTIVE DEBRIS FORMING A VFR CIG MAY
LINGER OVERNIGHT IF TSRA CLUSTERS FORM UPSTREAM AS SUGGESTED BY
GUIDANCE. MRNG RESTRICTIONS ARE NOT OUT OF THE QUESTION IF A TSRA
DOES AFFECT THE FIELD THIS AFTN...ESP IF SAID DEBRIS DOES NOT FORM
AND RADIATION IS MAXIMIZED UNDER LIGHT FLOW REGIME. DIURNAL CU WILL
LIKELY FORM A BIT LOWER SATURDAY BUT STILL VFR. WINDS PREVAILING
NWLY INTO SAT MRNG BUT THEN WILL BACK TO A NEAR CROSSWIND AS LEE
TROUGH DEVELOPS.
ELSEWHERE...CONVECTIVE CHANCES THIS AFTN ARE OVERALL NOT AS HIGH AS
THE PAST COUPLE OF DAYS...BUT STILL WARRANTS A MENTION AT ALL SITES
EXCEPT KAND. BEST CHANCES ARE ACTUALLY EAST OF THE BLUE RIDGE IN THE
VICINITY OF A SMALL SHORTWAVE THAT WILL MOVE SEWD ACRS THE PIEDMONT
THIS AFTN. GUSTY WINDS OF 20-25 KT AND BRIEF MVFR VSBY COULD OCCUR
WITH ANY TSRA. EXCEPT IN THE VCNTY OF TSRA...NW TO W WINDS WILL
PREVAIL THOUGH SOME VARIABILITY IS LIKELY GIVEN THE WEAK FLOW. MTN
VALLEY FOG LIKELY AGAIN TONIGHT AND RAINFALL THIS AFTN WILL ENHANCE
THE FOG POTENTIAL AS USUAL. NW TO WNW WINDS PREVAIL SAT WITH LEE
TROUGH TO THE E.
OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
ARE EXPECTED INTO THE WEEKEND...WITH THE GREATEST COVERAGE ACROSS
THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN
VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF
RECENT RAINFALL.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 88% HIGH 87%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...STAARMANN
NEAR TERM...WIMBERLEY
SHORT TERM...JOH
LONG TERM...JPT
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1040 AM EDT FRI JUN 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AS AN UPPER RIDGE GRADUALLY BREAKS DOWN
TODAY. THIS SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS MUCH OF THE AREA OVER THE WEEKEND. TYPICAL
SUMMERTIME WEATHER CONTINUES ACROSS THE REGION NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
1030 AM UPDATE...SCATTERED TSTMS CONTINUE TO BUBBLE ACRS UPPER EAST
TN AND SW VA UNDERNEATH A VERY WEAK SHORTWAVE ROUNDING THE UPPER
RIDGE...WITH ADDITIONAL FORCING LIKELY COMING FROM THE MEAN NWLY
FLOW INTO THE HIGHER TERRAIN. SOME OF THIS ACTIVITY HAS ALREADY
MOVED ACRS THE NC BORDER AND OVERALL IT SHOULD SPREAD INTO THE NRN
FOOTHILLS/PIEDMONT THRU MIDDAY FOLLOWING THE WAVE.
HOWEVER...DOWNSLOPING SEEMS TO BE ACTING AGAINST THE LEADING CELLS
ATTM AND THIS SHOULD KEEP COVERAGE RATHER LOW.
LATEST RUNS OF CONVECTION ALLOWING MODELS SHOW FAIRLY LIMITED
COVERAGE AS THE DAY PROGRESSES. THE 12Z NAM FOLLOWS THE 06Z IN
OVERDOING SBCAPE THIS AFTN ACRS PORTIONS OF THE AREA...HAVING 4000
OR MORE J/KG ALONG WITH DEWPOINTS IN THE UPPER 70S. CURRENT READINGS
ARE MOSTLY IN THE MID 60S AND WITH MEAN NLY FLOW IT JUST DOESN/T
SEEM PLAUSIBLE TO EXPECT THEM TO SKYROCKET. 12Z AREA RAOBS SHOW SOME
DRIER AIR JUST OFF THE SFC AND SOME GUIDANCE...INCLUDING THE
RAP...SHOW DEWPOINTS DROPPING SEVERAL DEGREES THIS AFTN. CAPE VALUES
FROM THE RAP ARE ACCORDINGLY MUCH LOWER. I WILL CLOSELY MONITOR
DEWPOINTS OVER THE NEXT COUPLE HRS TO SEE IF THEY INDEED MIX
OUT...AND HAVE PRELIMINARILY LOWERED POPS OVER THE PIEDMONT THIS
AFTN CLOSER TO CLIMO VALUES GIVEN THIS EXPECTATION.
PREVIOUS DISCUSSION...
AS OF 315 AM EDT FRIDAY...UPPER RIDGE NOW CENTERED OVER THE
MISSISSIPPI DELTA WILL SLOWLY CONTINUE TO RETROGRADE WEST ALLOWING
THE UPPER PATTERN ACROSS THE EASTERN CONUS TO FLATTEN. AT THE
SURFACE...A WEAK FRONTAL BOUNDARY THAT PUSHED THROUGH THE REGION ON
THURSDAY EVENING WILL REMAIN ALONG THE GA/SC COASTLINE LEADING TO
PREVAILING WEST NORTHWEST FLOW ACROSS THE SOUTHERN APPS ON FRIDAY.
THIS WILL YIELD SLIGHTLY LOWER DEWPOINTS ACROSS THE REGION THAN DAYS
PAST...THEREBY LEADING TO LESS DIURNAL INSTABILITY. HOWEVER...IT IS
STILL JUNE AND LAPSE RATES...AND MOISTURE...WILL BE SUFFICIENT FOR
SHOWER AND THUNDERSTORM DEVELOPMENT IF LIFT IS PROVIDED. WITH
THAT...THE LATEST 12KM NAM INDICATES A SERIES OF H5 IMPULSES
EJECTING THROUGH THE MEAN UPPER NW FLOW AND INTO THE FORECAST AREA
THIS AFTERNOON AND EVENING. EXPECTING CONVECTIVE INITIATION ACROSS
THE NC PIEDMONT THIS AFTERNOON WHEN PEAK HEATING COMBINES WITH THE
FIRST OF THE SERIES OF UPPER IMPULSES. THIS CONVECTION WILL LIKELY
PROPAGATE SOUTHEAST INTO PORTIONS OF THE UPSTATE BEFORE EXITING INTO
THE MIDLANDS AFTER SUNSET.
MEANWHILE...EXPECTING AN MCS TO BE PUSHING TOWARDS THE SOUTHERN APPS
OUT OF EASTERN KY AND MIDDLE TN. IF THE ATMOSPHERE IS NOT TOO
WORKED OVER FROM PREVIOUS CONVECTION...COULD SEE THIS MCS ENTERING
THE TERRAIN...POTENTIALLY PUSHING INTO THE FOOTHILLS BEFORE DECAYING
BY EARLY MORNING. THUS...FORECAST WILL FAVOR INCREASING POPS TO
SOLID CHANCE LEVELS ACROSS THE ENTIRE REGION FOR THE LATE AFTERNOON
AND EARLY EVENING HOURS BEFORE DECREASING ACROSS THE EAST LATE IN
THE EVENING. POPS WILL REMAIN ELEVATED AT CHANCE LEVELS ACROSS THE
HIGH TERRAIN DUE TO POTENTIAL OF ABOVE MENTIONED MCS AND WEAK NW
UPSLOPE FLOW. NOT EXPECTING ANY WIDESPREAD SEVERE THREATS WITH ANY
THUNDERSTORMS THAT DO DEVELOP DUE TO HIGH LFCS AND POOR MID LEVEL
LAPSE RATES. HOWEVER...CANNOT RULE OUT AN OCCASIONAL SEVERE
DOWNBURST WITH ANY COLLAPSING STORMS AS INVERTED V SOUNDINGS ARE
PRESENT PER LATEST NAM FORECAST PROFILES. TEMPERATURES THROUGH THE
NEAR TERM PERIOD WILL REMAIN ABOVE NORMAL.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 230 AM FRIDAY...MODELS CONTINUE TO INDICATE THAT H5 HEIGHTS
WILL SLOWLY FALL ACROSS THE REGION SAT/SUN AS AN UPPER H5 HIGH
RETROGRADES TOWARD THE SOUTH CENTRAL STATES AND AN UPPER TROUGH
ROTATES OFF THE NE COAST. A SERIES OF UPPER IMPULSES WILL TRIGGER
MCS/MCC OVER THE OHIO VALLEY FRI NIGHT AND PROPAGATE TOWARD THE
NORTHERN NC PIEDMONT THRU EARLY SAT. HOWEVER...WITH THE LOSS OF
HEATING/CAPE OVERNIGHT...THIS SYSTEM SHOULD WEAKEN CONSIDERABLY AS
IT PASSES JUST TO OUR NORTH. HENCE...HAVE INHERITED LOW END CHANCE
POPS MAINLY IN THE NORTHERN ZONES SAT MORNING. FOR SAT AFTERNOON...A
BACK DOOR FRONTAL BOUNDARY WILL PUSH SOUTH...WITH SHOWERS AND
THUNDERSTORMS DEVELOPING ALONG THE FRONT MAINLY IN THE NC PIEDMONT
ZONES. THE NAM/GFS KEEPS THE CONDITIONS RELATIVELY DRY IN THE
MTN/UPSTATE SC GIVEN MUCH DRIER PROFILE IN PREDOMINANT N/NW FLOW
ALOFT. WITH THE HELP OF DOWNSLOPING WINDS...TEMPERATURES WILL BE
AROUND 3-5 DEGREES ABOVE NORMAL OVER THE PIEDMONT WITH NEAR NORMAL
IN THE MTNS.
SUN...HIGH PRESSURE CENTERED OVER THE NE WILL NOSE DOWN INTO THE
REGION...WITH ANOTHER ROUND OF MCS/MCC DEVELOPING OVER IN THE
VICINITY OF KY/OHIO VALLEY...PROPAGATING SOUTHWARD TOWARD THE
SOUTHERN APPALACHIANS SUN AFTERNOON. THIS FEATURE WILL REACH THE TN
BORDERLINE AROUND 21Z SUN PER LATEST NAM AND WEAKENS CONSIDERABLY
(THE NAM TOTALLY DRIES OUT) AS IT MOVES ACROSS EAST OF THE MTNS.
THIS IS DUE TO THE PREVAILING N/NW DOWNSLOPE WINDS YIELDING MUCH
DRIER PROFILE/STABLE ENVIRONMENT OVER THE PIEDMONT. HENCE...POPS
REMAIN IN THE SLIGHT CHANCE/LOW CHANCE RANGE ACROSS MUCH OF THE
REGION...WITH BETTER CHANCE IN THE MTN ZONES. TEMPERATURES WILL COOL
DOWN BY 2-3 DEGREES ON SUN.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 130 AM EDT FRIDAY...THE LATEST GLOBAL MODELS AGREE THAT WEAK
UPPER RIDGING WILL BUILD ACROSS THE SE U.S. MONDAY IN RESPONSE TO AN
APPROACHING UPPER TROUGH FROM THE UPPER MIDWEST. HOWEVER...MODELS
CONTINUE TO DIVERGE QUIET A BIT BY TUE...WITH THE GFS EARLIER AND
DEEPER WITH THE TROUGH PERSISTING ACROSS THE EASTERN STATES LATE TUE
INTO FRI. MEANWHILE...THE ECMWF SUGGESTS THAT RATHER WEAK UPPER
TROUGH WILL PASS NORTH OF THE REGION LATE WED...WITH AN UPPER RIDGE
BUILDING BACK IN FROM THE WEST BY THU.
AT THE SURFACE...HIGH PRESSURE WILL WEAKEN AND GRADUALLY SHIFT EAST
MON INTO TUE AS A COLD FRONT APPROACHES FROM THE WEST. THE
COMBINATION OF INCREASING ATLANTIC MOISTURE ADVECTION IN SELY
FLOW...WEAKLY SHEARED ENVIRONMENT AND MODERATE DIURNAL BUOYANCY...WE
WILL SEE SOLID CHANCE OF PULSE TYPE CONVECTION ACROSS MUCH OF THE
REGION...FAVORING IN THE MTN ZONES. BOTH THE GFS AND ECMWF PUSH A
COLD FRONT FROM WEST TO EAST THROUGH THE REGION ON WED YIELDING
GREATER COVERAGE OF CONVECTION. WEAK SURFACE HIGH RETURNS ON
THURSDAY WITH DIURNALLY DRIVEN CONVECTION EXPECTED. TEMPERATURES
WILL REMAIN NEAR NORMAL RANGE THROUGH THE PERIOD.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AT KCLT...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD WITH THE
EXCEPTION OF MVFR VISB RESTRICITONS DUE TO POSSIBLE AFTERNOON TSRA.
FEW/SCT HIGH CIRRUS WILL PERSIST THROUGH THE MID/LATE MORNING BEFORE
GIVING WAY TO SCT LOW VFR CU AS HEATING BUILDS AND LAPSE RATES
STEEPEN IN THE PBL. EXPECTING A BKN CU FIELD TO DEVELOP ACROSS THE
PIEDMONT IN THE EARLY AFTERNOON HOURS OF PEAK HEATING...ALONG WITH
INCREASING INSTABILITY AND TSRA POTENTIAL. BACKED UP BY ONE HOUR
AND KEPT PREVIOUS TSRA MENTION IN THE FORM OF A TEMPO FROM 19-23Z.
WINDS THROUGH THE PERIOD WILL REMAIN WEST NORTHWESTERLY AND IN THE
5-8KTS RANGE BEFORE CALMING THIS EVENING.
ELSEWHERE...FEW TO SCT MID/HIGH CLOUDS WILL PREVAIL THROUGH MID
MORNING BEFORE ALL SITES EXPERIENCE DEVELOPING CU THROUGH THE
HEATING OF THE DAY. KEPT PREVIOUS WX MENTIONS AT ALL SITES FOR
POSSIBLE AFTERNOON TSRA AND MVFR RESTRICTIONS IN THE FORM OF TEMPO
OR PROB30 DEPENDING ON TIMING AND CONFIDENCE AT THE SITE. ADDED
PROB30 NEAR THE END OF THE PERIOD FOR KAVL AS NORTHWEST FLOW COULD
PROLONG SHOWER ACTIVITY INTO THE EARLY MORNING HOURS WITH IFR
RESTRICITONS POSSIBLE. WINDS THROUGH THE PERIOD WILL REMAIN WEST
NORTHWESTERLY AND IN THE 5-8KTS RANGE THROUGH THE AFTERNOON MIXING
HOURS.
OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
ARE EXPECTED INTO THE WEEKEND...WITH THE GREATEST COVERAGE ACROSS
THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN
VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF
RECENT RAINFALL.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-14Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% MED 62%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JOH
NEAR TERM...CDG/WIMBERLEY
SHORT TERM...JOH
LONG TERM...JOH
AVIATION...CDG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
145 AM EDT FRI JUN 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AS AN UPPER RIDGE GRADUALLY BREAKS DOWN
TODAY. THIS SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND
THUNDERSTORMS ACROSS MUCH OF THE AREA OVER THE WEEKEND. TYPICAL
SUMMERTIME WEATHER CONTINUES ACROSS THE REGION NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 145 AM EDT FRIDAY...SCATTERED TO BROKEN MID/HIGH DEBRIS CLOUDS
FROM DECAYING UPSTREAM CONVECTION ACROSS NORTHEAST TN CONTINUE TO
STREAM IN ALOFT ACROSS THE REGION. LIKEWISE...A MOIST PBL HAS
ALLOWED FOR DEVELOPMENT OF LOW STRATUS IN AND AROUND THE MOUNTAINS
VALLEYS...ALONG WITH AREAS OF PATCHY FOG. STILL EXPECTING THIS TO
CONTINUE THROUGH THE OVERNIGHT BEFORE SUNRISE...THEN ERODE SHORTLY
THEREAFTER. THUS...NO CHANGES MADE/NEEDED TO THE EXTREME NEAR TERM
PORTION OF THE FORECAST.
PREVIOUS DISCUSSION...
EVENING UPDATE...SHOWERS ARE LEAVING THE FCST AREA TO THE SOUTH
WHILE ANOTHER LINE OF WEAK CONVECTION APPROACHES THE NRN MTNS. DON/T
ANTICIPATE MUCH EFFECT FROM THESE STORMS AS THEY APPROACH AND WEAKEN
ON THE TN UPSLOPE SIDE. CAM MODELS ARE OVERDONE WITH THE UPPER
ENERGY SUPPORT...EXCEPT FOR THE HRRR WHICH INDICATES A WEAKENING
TREND...ALBEIT IN THE WRONG LOCATION. ANYWAY...CURRENT POPS HAVE
THIS FEATURE IN HAND. THERE WILL BE ANOTHER AREA OF ACTIVITY
APPROACHING THE NC MTNS THROUGH THE OVERNIGHT AS UPPER HEIGHTS
FALL...BUT A STRONG MCS TYPE STORM IS UNLIKELY THIS FAR SOUTH. MIN
TEMPS LOOK GOOD AND THERE COULD BE AREAS OF DENSE VALLEY FG
OVERNIGHT.
730 PM EDT UPDATE...IMPROVING CONDS OVER THE NEXT COUPLE HRS
CWFA/WIDE. A COUPLE SHORT LIVED -SHRA ARE DEVELOPING ALONG EXISTING
OUTFLOW BOUNDARIES...HOWEVER DRIER AIR IS WORKING IN ALOFT AND WILL
HELP DISSIPATE DEBRIS CLOUDINESS AND ANY DEEP CONV POTENTIAL THIS
EVENING. MADE SOME TWEAKS TO THE T/TDS GRIDS BASED ON PREVIOUS
PRECIPITATION AND LOWERED POPS TO LESS THAN SLIGHT ACROSS THE NRN
ZONES.
430 PM EDT UPDATE...ONGOING CONVECTION HAS BECOME QUITE STRONG TO
SEVERE WITH A FEW STORMS ACROSS THE NC MTNS AND FTHILLS. UPPER BROAD
S/W IS ENHANCING DEEP CONVECTION AND ALLOWING THE STORMS ACROSS THE
FTHILLS TO TAP INTO VERY HIGH VALUES OF DCAPE. THE CLT TDWR
INDICATED A WIDE AREA OF VELOCITIES WITH ONE STORM ON THE ORDER OF
50+ KTS...NO DOUBT KNOCKING DOWN SEVERAL TREES AND PWR LINES.
THUS...A WIND THREAT SEEMS MORE PROBABLE AS THE STORMS MOVE INTO THE
PIEDMONT OF THE CAROLINAS THIS AFTERNOON. QUARTER SIZE HAIL HAS BEEN
PRETTY MUCH THE LARGEST REPORTED SO FAR...EVEN WITH VERY TALL AND
ROBUST STORMS. MAKES SENSE WITH THE RELATIVELY WARM MLVLS AND HIGH
FREEZING LEVELS. WILL EXPECT THE BEST COVERAGE OF TSTMS OVER THE
I/77 CORRIDOR THROUGH 23Z WITH STORMS ALSO DEVELOPING SOUTH OVER NE
GA AND ACROSS NRN UPSTATE.
AS OF 215 PM EDT...ISOLD DEEP CONVECTION HAS KICKED OFF OVER THE
HIGHER MTNS...WITH CELLS LINED UP UPSTREAM ACRS THE GREAT TENN VALLEY
AS WELL...UNDER A WEAK SHORTWAVE ROUNDING THE RIDGE OVER THE SERN
STATES. ACTIVITY ALONG THE OLD OUTFLOW BDY ACRS FAR ERN KY AND SRN WV
STILL SAGGING SOUTH. LATEST MESO MODELS SHOW BOTH OF THESE LINEAR
FEATURES MOVING TOWARD OUR CWFA THRU THE REST OF THE AFTN. INFLOW
WINDS ARE WEAK...BUT INSTABILITY AHEAD OF THE LINES IS STRONG AS ONE
MIGHT EXPECT. IT LOOKS LIKE THE MESO GUIDANCE IS SUGGESTING MORE OF A
PROPAGATION INTO OUR AREA AND SUBSEQUENT REDEVELOPMENT ALONG REMNANT
BOUNDARIES. NONETHELESS...HIGHEST POPS REMAIN OVER THE MTNS WITH A
LATER INCREASE IN POPS OVER THE PIEDMONT AS ROUNDS OF STORMS FORM
ACRS THE AREA.
TONIGHT...MOST OF THE ENERGY WITH THE AFOREMENTIONED SHORTWAVE MOVES
OFF THE MID-ATLANTIC COAST BUT SOME WEAK DPVA MAY TRAIL IT...MOVING
SEWD ACRS THE CWFA THIS EVENING. A MINOR LLVL BOUNDARY IS SHOWN TO
MOVE SWD IN THE WAKE OF THE WAVE AS HIGH PRESSURE BUILDS SLIGHTLY S
AND E OUT OF THE GREAT LAKES AREA. SOME LINGERING MUCAPE IS SHOWN
THOUGH IT DIMINISHES AND IS INHIBITED AND WELL ELEVATED ANYWAY. IT
APPEARS MOST LIKELY THAT ANY REMAINING CONVECTION ALONG BOUNDARIES IN
OR INVOF THE FA WILL DIMINISH EXCEPT PERHAPS IN THE MTNS. LOWS WILL
BE NEAR NORMAL.
FRIDAY...FLOW ACRS THE SRN CONUS GENERALLY BECOMES MORE ZONAL.
NORTHERLY FLOW PERSISTS WITH LOW PRS OFF THE ATLANTIC COAST AND SOME
SEMBLANCE OF THE BOUNDARY REMAINING IN THE AREA...THOUGH ONLY
PROVIDING VERY WEAK CONVERGENCE. OVERALL...THE FA REMAINS UNDER
WEAKLY SHEARED BUT SEASONABLY HOT AND UNSTABLE CONDITIONS. LAPSE
RATES ARE SHOWN TO BE A LITTLE WEAKER THAN THOSE SEEN TODAY...WITH
LOWER CAPE VALUES DURING PEAK HEATING. VALUES HOWEVER REMAIN HIGH
ENOUGH TO EXPECT A SMALL SEVERE THREAT...FROM DOWNBURST WIND AND
HAIL.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
AS OF 145 PM THURSDAY...CHANGES TO THE OVERALL PATTERN WILL BE
TYPICALLY SUBTLE DURING THE SHORT TERM PERIOD...AND ARE UNLIKELY TO
HAVE A GREAT DEAL OF IMPACT ON THE SENSIBLE WEATHER. THE UPPER RIDGE
IS FORECAST TO SLOWLY RETROGRADE TOWARD THE SOUTH CENTRAL CONUS AND
WEAKEN DURING THE PERIOD...PLACING THE SOUTHEAST AND MID-ATLANTIC
ALONG THE SOUTHERN PERIPHERY OF THE WESTERLIES...WITH A DEEP NW FLOW
ANTICIPATED ACROSS OUR AREA. WHILE THIS WILL THEORETICALLY RENDER
THE AREA MORE SUSCEPTIBLE TO ORGANIZED CONVECTION MOVING OUT OF THE
OHIO VALLEY REGION...BASED UPON WIND PROFILES...IT IS DOUBTFUL THAT
ANYTHING TOO ORGANIZED AND SELF-SUSTAINING WILL BE ABLE TO DEVELOP
UPSTREAM...AS ONE MAY NEED TO TRAVEL AS FAR NORTH AS THE CANADIAN
BORDER TO FIND ROBUST SHEAR. NEVERTHELESS...WITH A WEAK COLD FRONT
APPROACHING THE REGION...AND HALFWAY DECENT STEERING CURRENTS (MEAN
CLOUD BEARING WINDS ON THE ORDER OF 15-20 KTS...ABOVE CLIMO POPS
(GENERALLY 30-40 PERCENT DURING THE AFTERNOON/EVENING...20/30
PERCENT DURING THE EARLY MORNING HOURS) APPEAR WARRANTED THROUGH THE
PERIOD.
THE WEAK COLD FRONT MAY BACK DOOR ITS WAY THROUGH THE AREA BY THE
END OF THE WEEKEND...POSSIBLY KNOCKING TEMPS DOWN TO NEAR...OR
SLIGHTLY BELOW CLIMO ACROSS THE NC PIEDMONT...IN ADDITION TO
PROVIDING A FOCUS FOR INITIATION OF AFTERNOON/EVENING SHOWERS AND
STORMS. OVERALL...TYPICAL EARLY SUMMER WEATHER APPEARS IN STORE THIS
WEEKEND...WITH PERHAPS SLIGHTLY HIGHER COVERAGE OF CONVECTION THAN
IS TYPICAL.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 1245 PM THURSDAY...NO BIG CHANGES WERE MADE TO THE FCST IN THE
MEDIUM RANGE.
THE UPPER PATTERN WILL BE PROGRESSIVE...WITH RELATIVELY FLAT FLOW
ACRS THE ERN CONUS. THE WESTERLIES/POLAR JET WILL STAY WELL NORTH OF
THE CWFA. SO EXPECT PRIMARILY DIURNALLY-DRIVEN CONVECTION EVERY DAY
THRU LATE NEXT WEEK. THE OPERATIONAL GFS AND ECWMF DIVERGE QUITE A
BIT BY MIDWEEK...WITH THE GFS EARLIER AND DEEPER WITH A LONGWAVE
TROF ACRS THE MIDWEST TO THE GREAT LAKES. THE ECMWF KEEPS STRONGER
RIDGING ALONG THE EAST COAST. THE GFE/ECMWF ENSEMBLE MEANS WERE A
COMPROMISE AND PREFERRED BY WPC. THIS KEEPS ANY SIGNIFICANT/SYNOPTIC
FRONTAL BOUNDARIES TO OUR NORTH AND WEST THRU THURSDAY. I BLENDED
THE WPC/CONS/BCCONSALL WITH OFFICIAL...WHICH RESULTS IN ONLY SMALL
CHANGES. BEST COVERAGE OF CONVECTION WILL BE ACRS THE MTNS EACH DAY.
TEMPS WILL CONTINUE TO BE SLIGHTLY ABOVE NORMAL THRU THE MEDIUM
RANGE.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AT KCLT...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD WITH THE
EXCEPTION OF MVFR VISB RESTRICITONS DUE TO POSSIBLE AFTERNOON TSRA.
SCT/BKN HIGH LEVEL DEBRIS CLOUDS WILL PERSIST THROUGH THE OVERNIGHT
BEFORE GIVING WAY TO SCT LOW VFR CU BY LATE MORNING AS HEATING
BUILDS AND LAPSE RATES STEEPEN IN THE PBL. EXPECTING A BKN CU FIELD
TO DEVELOP ACROSS THE PIEDMONT IN THE AFTERNOON HOURS OF PEAK
HEATING...ALONG WITH INCREASING INSTABILITY AND TSRA POTENTIAL.
KEPT PREVIOUS PROB30 GROUP FOR MVFR 4SM TSRA FROM 20-24Z TO
ACCOUNT. WINDS THROUGH THE PERIOD WILL REMAIN WEST NORTHWESTERLY
AND IN THE 5-8KTS RANGE BEFORE CALMING THIS EVENING.
ELSEWHERE...VFR CONDITIONS WILL PREVAIL THROUGH THE OVERNIGHT AT ALL
SITES WITH THE EXCEPTION OF KAVL AND KHKY WHERE FOG RESTRICITIONS
ARE LIKELY. ALREADY SEEN IFR CONDITIONS AT KAVL WITH SOME RECOVERY
AT THE PRESENT TIME. EXPECTING CONDITIONS TO DETERIORATE ONCE
AGAIN AS THE MOIST PBL DECOUPLES. ALSO EXPECTING RESTRICTIONS AT
KHKY THUS INCLUDED TEMPO FOR MVFR FOG...AND PREVAILED MVFR FOG WITH
AN IFR TEMPO DUE TO VISB/CIGS AT KAVL. OTHERWISE...MID/HIGH DEBRIS
CLOUDS WILL PREVAIL INTO MID MORNING BEFORE ALL SITES EXPERIENCE
DEVELOPING CU THROUGH THE HEATING OF THE DAY. KEPT PREVIOUS PROB30
MENTIONS AT ALL SITES FOR POSSIBLE AFTERNOON TSRA AND MVFR
RESTRICTIONS. WINDS THROUGH THE PERIOD WILL REMAIN WEST
NORTHWESTERLY AND IN THE 5-8KTS RANGE THROUGH THE AFTERNOON MIXING
HOURS.
OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
ARE EXPECTED INTO THE WEEKEND...WITH THE GREATEST COVERAGE ACROSS
THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN
VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF
RECENT RAINFALL.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT HIGH 100% HIGH 100% HIGH 100% LOW 45%
KGSP HIGH 100% HIGH 100% HIGH 100% LOW 45%
KAVL HIGH 98% HIGH 98% HIGH 100% LOW 45%
KHKY HIGH 100% HIGH 95% HIGH 100% LOW 45%
KGMU HIGH 100% HIGH 100% HIGH 100% LOW 45%
KAND HIGH 100% HIGH 91% HIGH 100% LOW 45%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...ARK
NEAR TERM...CDG/SBK/WIMBERLEY
SHORT TERM...JDL
LONG TERM...ARK
AVIATION...CDG
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
905 PM MDT SAT JUN 21 2014
.UPDATE...
ISSUED AT 901 PM MDT SAT JUN 21 2014
IT LOOKS LIKE THE SEVERE THREAT IS TAPERING OFF SO HAVE ALLOWED
THE SVR TSTM WATCH TO EXPIRE AS SCHEDULED. ISOLD-SCT THUNDERSTORMS
ARE STILL EXPECTED OVERNIGHT AS MODELS INDICATED ABUNDANT MID
LEVEL INSTABILITY. LOCALLY HEAVY RAIN WILL BE POSSIBLE OVER PARTS
OF WESTERN SOUTH DAKOTA.
&&
.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 210 PM MDT SAT JUN 21 2014
A BROAD NORTH/SOUTH PRE-FRONTAL SURFACE TROUGH ACROSS
THE WESTERN AND CENTRAL DAKOTAS DOMINATES THE SURFACE MAP THIS
AFTERNOON. THE TROUGH EXTENDS SOUTHWARD FROM A NEARLY STATIONARY LOW
OVER SOUTH CENTRAL CANADA. A WEAK COLD FRONT ALSO EXTENDS SOUTHWARD
FROM THIS LOW THROUGH EASTERN MONTANA AND NORTH CENTRAL WYOMING.
DEWPOINT TEMPERATURES AHEAD OF THE TROUGH IN CENTRAL AND EASTERN
SOUTH DAKOTA ARE IN THE MID 60S...WHILE DEWPOINTS BEHIND THE COLD
FRONT DROP INTO THE MID 40S. ONLY VERY WEAK UPPER LEVEL IMPULSES
ARE DISCERNABLE IN THE MOSTLY ZONAL FLOW ACROSS THE NORTHERN PLAINS
TODAY. SOME WEAK CONVECTION HAS FIRED UP ALONG THE COLD FRONT IN
NORTHEAST WYOMING AND EASTERN MONTANA BUT IR IMAGERY INDICATES
MINIMAL VERTICAL DEVELOPMENT. A WEAKER SURFACE LOW RESIDES OVER
EASTERN COLORADO...SUPPORTING A MOSTLY STATIONARY EAST-WEST WARM
FRONT BOUNDARY ALONG THE NEBRASKA SOUTH DAKOTA BORDER. LITTLE OR NO
CONVECTIVE DEVELOPMENT HAS TAKEN PLACE ALONG THIS BOUNDARY. MORNING
SOUNDINGS AT BOTH UNR AND LBF INDICATE A STRONG CAP BELOW 700 MB
WITH A DRY LAYER JUST OFF THE SURFACE AND THEN UNSTABLE LAPS RATES
AT MID LEVELS. TRIGGER TEMPERATURES AT BOTH LOCATIONS ARE IN THE MID
80S.
THIS EVENING...THE KEY FOR LOCATING THE CONVECTIVE DEVELOPMENT THIS
EVENING WILL BE THE LOCATION OF THE VERY DIFFUSE BOUNDARY COINCIDING
WITH THE WESTERN DAKOTAS TROUGH. THE HRRR GUIDANCE MAINTAINS A LINE
OF THUNDERSTORMS FROM THE SOUTHWEST CORNER OF SOUTH DAKOTA TO
CENTRAL SOUTH DAKOTA AS WELL AS AN AREA OF POST FRONTAL STORMS OVER
NORTHEAST WYOMING. THE COMBINATION OF MID LEVEL INSTABILITY...LARGE
CAPE VALUES OVER 2000 J/KG AND ADEQUATE BULK SHEAR OF 30 TO 40 KTS
WILL SUPPORT SUPERCELL DEVELOPMENT CAPABLE OF PRODUCING STRONG WINDS
GUSTS AND LARGE HAIL. IT APPEARS AT THIS TIME THAT MOST OF THE
ACTION THIS AFTERNOON WILL TAKE PLACE EAST AND SOUTH OF THE BLKHLS
REGION WITH SOMEWHAT WEAKER ACTIVITY OVER NORTHEAST WYOMING.
OVERNIGHT TONIGHT...THE SURFACE FRONT WILL SLOWLY SHIFT SOUTH AND
EAST DURING THE LATE EVENING. STRONG TO SEVERE STORMS ARE LIKELY
ALONG OR NEAR THE FRONTAL BOUNDARY AS IT CONTINUES EASTWARD INTO
CENTRAL SOUTH DAKOTA BY 04Z. A WEAK UPPER LEVEL IMPULSE IS EXPECTED
TO MOVE INTO NORTHEAST WYOMING AND AND A BROAD AREA OF ISENTROPIC
UPGLIDE IS FORECAST TO DEVELOP OVER THE SHALLOW COOL AIR IN WESTERN
SOUTH DAKOTA AND NORTHEAST WYOMING MOSTLY SOUTH OF US HWY 212
RESULTING IN A STRATIFORM PRECIP EVENT FOR AREAS STRETCHING FROM
AROUND THE BLKLHS TO THE MORVR. TEMPERATURES WILL COOL INTO THE 50S
TO LOWER 60S.
SUNDAY...OVERCAST SKIES AND STRATIFORM PRECIP SHOULD BE ONGOING
BEFORE SUN RISE IN NORTHEAST WYOMING AND THE BLKHLS AREA AND SPREAD
TO THE MORVR BEFORE NOON. ISOLATED THUNDERSTORMS ARE POSSIBLE...BUT
THESE SHOULD BE PRETTY WEAK. A MODERATE NORTHWEST BREEZE WILL
ACCOMPANY THE LIGHT RAIN. THE LIGHT RAIN IS EXPECTED TO BEGIN
TAPERING OFF BY 00Z AS THE COOL AIRMASS PUSHES FURTHER SOUTH AND
EAST. COOLER AIR WILL MOVE INTO THE NORTHERN PLAINS...WITH HIGH
TEMPERATURES 10 TO 15 DEGREES COOLER THAN TODAY...ONLY IN THE MID
60S TO UPPER 70S.
SUNDAY NIGHT...DISSIPATING PRECIPITATION AND SOME LINGERING CLOUD
COVER WILL KEEP TEMPERATURES FROM DROPPING BELOW THE LOWER 50S IN
MOST PLACES...UPPER 40S IN NORTHEAST WYOMING AND THE BLKHLS.
&&
.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 210 PM MDT SAT JUN 21 2014
AN UPPER LEVEL RIDGE OVER THE NORTHERN ROCKIES WILL SLOWLY EXPAND
EASTWARD MONDAY THROUGH THURSDAY. BY THURSDAY...AN UPPER LEVEL
TROUGH WILL HAVE DEVELOPED OVER SOUTHWEST CANADA/NORTHWEST US. THE
RESULT WILL BE WEST/NORTHWEST FLOW ALOFT EARLY IN THE PERIOD
TRANSITIONING TO SOUTHWEST FLOW ALOFT BY THE END OF THE WEEK. A
PARADE OF SHORTWAVES WILL BRING TSRA AT TIMES...ESPECIALLY DURING
THE AFTERNOON/EVENING HOURS GIVEN SLOWLY BUILDING THERMAL RIDGE OVER
THE NORTHERN PLAINS AND SUBSEQUENT SLIGHTLY HIGHER MLCIN VALUES.
GFS/ECMWF ARE IN GENERAL AGREEMENT...BUT BOTH HINT AT POSSIBLE BACK
DOOR COOL FRONTS TUESDAY OR WEDNESDAY FOR THE SD PLAINS GIVEN
PROXIMITY OF UPPER LOW OVER HUDSON BAY. DIDN/T DEVIATE MUCH FROM
GUIDANCE VALUES FOR TEMPERATURES.
&&
.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 516 PM MDT SAT JUN 21 2014
SCATTERED TSRA DEVELOP THIS EVENING AND SPREAD EASTWARD ACROSS THE
AREA. HAIL AND GUSTY WINDS ARE POSSIBLE WITH ANY STORMS INCLUDING
LOCAL IFR VSBYS/CIGS... PARTICULARLY FROM SOUTHWEST THROUGH SOUTH
CENTRAL SD. ANOTHER WAVE OF SHRA/TSRA WILL DEVELOP LATER TONIGHT
INTO SUNDAY MORNING RESULTING IN RATHER WIDESPREAD PRECIPITATION
COVERAGE ACROSS NORTHEASTERN WY/WESTERN SD...WITH AREAS OF MVFR
CIGS/VSBYS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...10
SHORT TERM...CARPENTER
LONG TERM...HELGESON
AVIATION...10
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
519 PM MDT SAT JUN 21 2014
.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 210 PM MDT SAT JUN 21 2014
A BROAD NORTH/SOUTH PRE-FRONTAL SURFACE TROUGH ACROSS
THE WESTERN AND CENTRAL DAKOTAS DOMINATES THE SURFACE MAP THIS
AFTERNOON. THE TROUGH EXTENDS SOUTHWARD FROM A NEARLY STATIONARY LOW
OVER SOUTH CENTRAL CANADA. A WEAK COLD FRONT ALSO EXTENDS SOUTHWARD
FROM THIS LOW THROUGH EASTERN MONTANA AND NORTH CENTRAL WYOMING.
DEWPOINT TEMPERATURES AHEAD OF THE TROUGH IN CENTRAL AND EASTERN
SOUTH DAKOTA ARE IN THE MID 60S...WHILE DEWPOINTS BEHIND THE COLD
FRONT DROP INTO THE MID 40S. ONLY VERY WEAK UPPER LEVEL IMPULSES
ARE DISCERNABLE IN THE MOSTLY ZONAL FLOW ACROSS THE NORTHERN PLAINS
TODAY. SOME WEAK CONVECTION HAS FIRED UP ALONG THE COLD FRONT IN
NORTHEAST WYOMING AND EASTERN MONTANA BUT IR IMAGERY INDICATES
MINIMAL VERTICAL DEVELOPMENT. A WEAKER SURFACE LOW RESIDES OVER
EASTERN COLORADO...SUPPORTING A MOSTLY STATIONARY EAST-WEST WARM
FRONT BOUNDARY ALONG THE NEBRASKA SOUTH DAKOTA BORDER. LITTLE OR NO
CONVECTIVE DEVELOPMENT HAS TAKEN PLACE ALONG THIS BOUNDARY. MORNING
SOUNDINGS AT BOTH UNR AND LBF INDICATE A STRONG CAP BELOW 700 MB
WITH A DRY LAYER JUST OFF THE SURFACE AND THEN UNSTABLE LAPS RATES
AT MID LEVELS. TRIGGER TEMPERATURES AT BOTH LOCATIONS ARE IN THE MID
80S.
THIS EVENING...THE KEY FOR LOCATING THE CONVECTIVE DEVELOPMENT THIS
EVENING WILL BE THE LOCATION OF THE VERY DIFFUSE BOUNDARY COINCIDING
WITH THE WESTERN DAKOTAS TROUGH. THE HRRR GUIDANCE MAINTAINS A LINE
OF THUNDERSTORMS FROM THE SOUTHWEST CORNER OF SOUTH DAKOTA TO
CENTRAL SOUTH DAKOTA AS WELL AS AN AREA OF POST FRONTAL STORMS OVER
NORTHEAST WYOMING. THE COMBINATION OF MID LEVEL INSTABILITY...LARGE
CAPE VALUES OVER 2000 J/KG AND ADEQUATE BULK SHEAR OF 30 TO 40 KTS
WILL SUPPORT SUPERCELL DEVELOPMENT CAPABLE OF PRODUCING STRONG WINDS
GUSTS AND LARGE HAIL. IT APPEARS AT THIS TIME THAT MOST OF THE
ACTION THIS AFTERNOON WILL TAKE PLACE EAST AND SOUTH OF THE BLKHLS
REGION WITH SOMEWHAT WEAKER ACTIVITY OVER NORTHEAST WYOMING.
OVERNIGHT TONIGHT...THE SURFACE FRONT WILL SLOWLY SHIFT SOUTH AND
EAST DURING THE LATE EVENING. STRONG TO SEVERE STORMS ARE LIKELY
ALONG OR NEAR THE FRONTAL BOUNDARY AS IT CONTINUES EASTWARD INTO
CENTRAL SOUTH DAKOTA BY 04Z. A WEAK UPPER LEVEL IMPULSE IS EXPECTED
TO MOVE INTO NORTHEAST WYOMING AND AND A BROAD AREA OF ISENTROPIC
UPGLIDE IS FORECAST TO DEVELOP OVER THE SHALLOW COOL AIR IN WESTERN
SOUTH DAKOTA AND NORTHEAST WYOMING MOSTLY SOUTH OF US HWY 212
RESULTING IN A STRATIFORM PRECIP EVENT FOR AREAS STRETCHING FROM
AROUND THE BLKLHS TO THE MORVR. TEMPERATURES WILL COOL INTO THE 50S
TO LOWER 60S.
SUNDAY...OVERCAST SKIES AND STRATIFORM PRECIP SHOULD BE ONGOING
BEFORE SUN RISE IN NORTHEAST WYOMING AND THE BLKHLS AREA AND SPREAD
TO THE MORVR BEFORE NOON. ISOLATED THUNDERSTORMS ARE POSSIBLE...BUT
THESE SHOULD BE PRETTY WEAK. A MODERATE NORTHWEST BREEZE WILL
ACCOMPANY THE LIGHT RAIN. THE LIGHT RAIN IS EXPECTED TO BEGIN
TAPERING OFF BY 00Z AS THE COOL AIRMASS PUSHES FURTHER SOUTH AND
EAST. COOLER AIR WILL MOVE INTO THE NORTHERN PLAINS...WITH HIGH
TEMPERATURES 10 TO 15 DEGREES COOLER THAN TODAY...ONLY IN THE MID
60S TO UPPER 70S.
SUNDAY NIGHT...DISSIPATING PRECIPITATION AND SOME LINGERING CLOUD
COVER WILL KEEP TEMPERATURES FROM DROPPING BELOW THE LOWER 50S IN
MOST PLACES...UPPER 40S IN NORTHEAST WYOMING AND THE BLKHLS.
&&
.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 210 PM MDT SAT JUN 21 2014
AN UPPER LEVEL RIDGE OVER THE NORTHERN ROCKIES WILL SLOWLY EXPAND
EASTWARD MONDAY THROUGH THURSDAY. BY THURSDAY...AN UPPER LEVEL
TROUGH WILL HAVE DEVELOPED OVER SOUTHWEST CANADA/NORTHWEST US. THE
RESULT WILL BE WEST/NORTHWEST FLOW ALOFT EARLY IN THE PERIOD
TRANSITIONING TO SOUTHWEST FLOW ALOFT BY THE END OF THE WEEK. A
PARADE OF SHORTWAVES WILL BRING TSRA AT TIMES...ESPECIALLY DURING
THE AFTERNOON/EVENING HOURS GIVEN SLOWLY BUILDING THERMAL RIDGE OVER
THE NORTHERN PLAINS AND SUBSEQUENT SLIGHTLY HIGHER MLCIN VALUES.
GFS/ECMWF ARE IN GENERAL AGREEMENT...BUT BOTH HINT AT POSSIBLE BACK
DOOR COOL FRONTS TUESDAY OR WEDNESDAY FOR THE SD PLAINS GIVEN
PROXIMITY OF UPPER LOW OVER HUDSON BAY. DIDN/T DEVIATE MUCH FROM
GUIDANCE VALUES FOR TEMPERATURES.
&&
.AVIATION...FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING
ISSUED AT 516 PM MDT SAT JUN 21 2014
SCATTERED TSRA DEVELOP THIS EVENING AND SPREAD EASTWARD ACROSS THE
AREA. HAIL AND GUSTY WINDS ARE POSSIBLE WITH ANY STORMS INCLUDING
LOCAL IFR VSBYS/CIGS... PARTICULARLY FROM SOUTHWEST THROUGH SOUTH
CENTRAL SD. ANOTHER WAVE OF SHRA/TSRA WILL DEVELOP LATER TONIGHT
INTO SUNDAY MORNING RESULTING IN RATHER WIDESPREAD PRECIPITATION
COVERAGE ACROSS NORTHEASTERN WY/WESTERN SD...WITH AREAS OF MVFR
CIGS/VSBYS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...CARPENTER
LONG TERM...HELGESON
AVIATION...10
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1258 AM CDT FRI JUN 20 2014
.UPDATE...
06Z UPDATED AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
TIGHT VORTICITY MAXIMA ROTATING OVER WESTERN SD AT THIS TIME HAS
PRODUCED THUNDERSTORMS...WHICH WAS WHAT THE HRRR MODEL WAS
INDICATING MOST OF THE DAY. SOME OF THESE STORMS HAVE BECOME
SEVERE WITH HAIL AND EVEN REPORTS OF FUNNEL CLOUDS/LANDSPOUTS. NOT
SURPRISING GIVEN COOLER TEMPS ALOFT AND TIGHT ROTATION OF VORT
SPINNING ACROSS. MLCAPE VALUES GENERALLY RANGE FROM 500 TO 1000
J/KG WITH DEEP LAYER SHEAR 20 TO 30 KNOTS OVER WESTERN SD.
ALTHOUGH...BETTER SHEAR VALUES EXIST OVER CENTRAL SD. HI RES
MODELS SHOW SOME OF THIS ACTIVITY SPREADING ACROSS THE CWA AS LONG
AS THE SUN IS UP. HAVE INCLUDED POPS THIS EVENING TO ACCOUNT FOR
THIS.
CONDITIONS QUIET DOWN LATE TONIGHT THROUGH FRIDAY NIGHT AS UPPER
LEVEL FLOW BECOMES ZONAL. GIVEN 850 MB TEMPS ON FRIDAY...EXPECT
HIGHS TO BE RATHER WARM WITH READINGS IN THE 80S.
MORE ACTIVE WEATHER RETURNS TO THE AREA SATURDAY AND SATURDAY
NIGHT. INSTABILITY INCREASES TO 2000 TO 3000 J/KG WITH 40 TO 50
KNOTS OF DEEP LAYER SHEAR. LOW LEVEL SHEAR NOT ALL TOO IMPRESSIVE.
COULD BE SEEING SOME SEVERE STORMS ACROSS THE AREA SATURDAY INTO
SATURDAY EVENING.
.LONG TERM...SUNDAY THROUGH THURSDAY
THE PERIOD STARTS OFF WITH FAIRLY FAST MOVING UPPER LEVEL FLOW
WITH A SERIES OF SHORTWAVES TRACKING ACROSS THE AREA. A LOW
PRESSURE SYSTEM WILL TRACK ACROSS THE CENTRAL PLAINS EARLY IN THE
PERIOD...PUTTING THE CWA IN A POTENTIAL SPOT FOR SHOWER AND
THUNDERSTORM ACTIVITY SUNDAY THROUGH EARLY TUESDAY. HIGH PRESSURE
DROPPING OVER THE NORTHERN PLAINS WILL KEEP THINGS DRY TUESDAY
NIGHT AND WEDNESDAY...THEN MAY SEE ANOTHER CHANCE OF PRECIPITATION
WEDNESDAY NIGHT AND THURSDAY AS A LOW PRESSURE SYSTEM APPROACHES
THE REGION.
NEAR NORMAL TEMPERATURES WILL BE THE RULE THROUGH THE
PERIOD...WITH HIGHS IN THE MID 70S TO LOWER 80S AND OVERNIGHT LOWS
IN THE MID TO UPPER 50S.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH FRIDAY EVENING FOR ALL
TERMINAL LOCATIONS. WITH LIGHT WINDS AND MOSTLY CLEAR SKIES AND
LOW DEW POINT SPREADS...EXPECT SOME FOG TO FORM TONIGHT AT ABR AND
ATY AND POSSIBLY AT MBG AND PIR.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...TMT
LONG TERM...PARKIN
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
252 PM EDT FRI JUN 20 2014
.SHORT TERM...(TONIGHT THROUGH SUNDAY)...AIRMASS WAS VERY UNSTABLE
ACROSS PLATEAU COUNTIES NE INTO ERN KY AND SW VA THIS AFTERNOON.
COVERAGE AND INTENSITY OF THUNDERSTORMS CONTINUES TO INCREASE WITH
MOVEMENT E OR SE AT AROUND 20 MPH. ALL OF THIS ACTIVIVTY IS POISED
TO SWEEP ACROSS OUR FORECAST AREA THIS EVENING...MUCH IN LINE WITH
RAP MODEL OVER THE NEXT FEW HOURS...WITH NAM SHOWING A BIT MORE
COVERAGE THAN RAP OR HRR. THINK NAM MAY BE OVERDOING CONVECTION OVER
SE TN AND SW NC...SO STUCK WITH 30 TO 40 PERCENT POPS FOR THOSE
AREAS. STORMS COULD BRIEFLY INTENSIFY TO MARGINALLY SEVERE WITH
STRONG WINDS AND LOCALLY HEAVY RAINS. GFS MOS MINS WERE CLOSE TO
PERSISTENCE AND GENERALLY FOLLOWED.
BETTER COVERAGE OF SHOWERS AND STORMS ON SATURDAY WILL BE EARLY...
FOLLOWED BY A DECREASING TREND IN POPS FOR SATURDAY NIGHT AND
SUNDAY. SHOULD BE DRY AFTER SUNSET SATURDAY THROUGH SUNDAY MORNING
WITH AREAS OF FOG LIKELY AGAIN. DROPPED POPS EARLIER IN GRIDS FOR
SATURDAY NIGHT AND LIMITED POPS FOR SUNDAY TO THE AFTERNOON HOURS.
LOW LEVEL FLOW BECOMES LIGHT NORTHERLY SATURDAY NIGHT SO A TAD
COOLER BUT STILL AROUND SEASONAL NORMS. FAVORED A BLEND OF SIMILAR
MOS MAXES EACH DAY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)...ATMOSPHERE BECOMES A
LITTLE MORE CONDUCIVE TO CONVECTION AROUND THE TUESDAY THROUGH
THURSDAY PERIOD AS A LONG WAVE TROUGH BUILDS INTO THE EASTERN U.S. A
COOL FRONTAL BOUNDARY WILL BUILD INTO THE REGION DURING THIS TIME
FRAME ADDING A BIT OF A FOCUS FOR STORM DEVELOPMENT IN THE WARM AND
HUMID AIRMASS WHICH WILL RESIDE OVER THE MID SOUTH. STAYED VERY
CLOSE TO SUGGESTED MIN TEMP MOS WHILE ADJUSTING MAX TEMPS ABOUT A
COUPLE OF DEGREES BELOW MAX TEMPERATURE GUIDANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 70 91 68 92 / 30 30 20 20
KNOXVILLE MCGHEE TYSON AIRPORT, TN 68 88 66 89 / 50 30 20 20
OAK RIDGE, TN 70 88 65 89 / 50 30 20 20
TRI CITIES AIRPORT, TN 64 84 60 86 / 60 40 20 20
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
605 PM CDT Sat Jun 21 2014
.AVIATION...
00Z TAF issuance
Showers and thunderstorms have mostly dissipated across the area
with partly cloudy skies left in their wake. Expect high clouds to
continue to stream across overnight with low clouds (MVFR or lower
cigs) filling in across the Permian Basin and SE NM. Low
clouds will lift by late morning with partly cloudy skies and weak
southeasterly flow by afternoon.
&&
.PREV DISCUSSION... /ISSUED 212 PM CDT Sat Jun 21 2014/
DISCUSSION...
A well defined Mexican moisture tap is still evident on water vapor
imagery with embedded shrtwv trof/s, one of which is lifting out
the area while another model depicted shrtwv trof follows and in
part is responsible for renewed SHRA/TSRA. The area where SHRA/TSRA
have been occurring is area co-located where 9h-85h mstr flux has
persisted and PWs are near 1.75" per GEFS (about 2.5 standard
deviations above normal). The RUC13 show this area of moisture
flux redeveloping to the n into the n-ne PB and thus we would not
be surprised to SHRA/TSRA develop into the n-ne these next few
hrs. Heavy rain is main concern and local flooding/flash flooding
is possible.
Mid level ridge will slowly builds in from the w and serve to
push the general mid level trof/moisture axis that has been over
the area to the e resulting in a decreased chance of rain and an
increase in temperatures. Still there are some opportunities for
precip. For Sunday PoPs will generally be confined to the mtns
where very steep LR/s of 8-9 c/km are to be coincident with sfc
dwpnts in the m40-50 along e slopes, flow will be upslope, and
CINH will be a non-issue in/near elevated heat sources. Meanwhile
Sunday night storms may near the far NW CWFA with shrtwv trof in
NW flow aloft. On Monday NAM12/ECMWF better depicts a shrtwv trof
in the NW flow and develops storms by mid/late afternoon in E-SE
NM and then in PB after 21Z. Development may be enhanced by a
boundary from previous convection and/or its own cold pool. Timing
will be important, if it does come thru early then there won`t be
much concern for precip into the evening. Tue models hint at tstms
from the mtns into E-SE NM where moist se low level flow and
secondary mid level theta-e ridge are expected to be. ECMWF wants
light up the mtns again Thur/Fri, while the GFS confines precip
moreso to the Davis mtns. As frequently is the case for the mtns
the development is tied to the mid level theta-e ridge axis and
based on consensus of data the Davis mtns are favored over the GDP
mtns. A mid level trof is progged to push in to the n Friday,
which may advect drier air ewd. Through the extended part of the
fcst the GFS is much warmer than ECMWF in part due to its more
veered/stronger wly winds which aids thermal ridge/dry air.
Climatology certainly favors the GFS and with warm temperatures
already in forecast with probably use a blender approach to catch
general trends.
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
29
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1247 PM CDT FRI JUN 20 2014
.AVIATION...
/18Z TAFS/
CONCERNS...A FEW ISOLATED SHOWERS OR POSSIBLY THUNDERSTORMS AROUND
KACT THIS AFTERNOON.
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE PERIOD WITH
BROKEN CIGS MAINLY DUE TO LOW LEVEL CUMULUS BETWEEN 4-6 KFT AND/OR
DENSE HIGH CLOUD COVER. SOME ADDITIONAL SCATTERED CU AROUND 2000-2500
FEET WILL OCCUR IN THE WACO AREA TOMORROW MORNING...AND COULD
POSSIBLY RESULT IN BKN SKIES FOR BRIEF PERIODS. THE WINDS WILL
REMAIN GENERALLY LESS THAN 10 KTS AND WILL VARY BETWEEN 150-220
DEGREES WITH SOUTHEAST WINDS MORE PREVALENT IN THE EVENING HOURS
AND SOUTHWEST WINDS MORE PREVALENT IN THE MORNING HOURS.
A FEW SHOWERS ARE POSSIBLE AROUND THE KACT AREA THIS AFTERNOON
FROM 21-01Z. IT IS POSSIBLE THAT A THUNDERSTORM OR TWO COULD ALSO
OCCUR WITHIN A 10SM RADIUS OF THE AIRPORT BUT WILL CARRY VCSH FOR NOW.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 312 AM CDT FRI JUN 20 2014/
UPPER LOW HAS MOVED TO SOUTHEASTERN MANITOBA...AND SHOULD START
PINWHEELING NORTH DURING THE DAY. RIDGE IS CENTERED OVER SOUTHERN
MISSISSIPPI VALLEY AND WILL SLOWLY SLIDE SOUTHWEST OVER NEXT
COUPLE OF DAYS. PWATS ARE ON THE WAY DOWN...FROM NEAR 2 INCHES
YESTERDAY TO ABOUT AN INCH AND A HALF TODAY. GUIDANCE IS
STRUGGLING WITH THE FEATURES THAT WILL DEFINE TODAY/S
WEATHER...FROM THE CURRENT CONVECTION IN SOUTHERN OKLAHOMA TO SEA
BREEZE TYPE SHOWERS MOVING IN FROM THE COAST.
AS I WRITE THIS...THE OKLAHOMA CONVECTION IS WEAKENING AND MAY BE
GONE BY 7 AM...BUT WILL KEEP A SMALL AREA OF ISOLATED THUNDER
NEAR THE RED RIVER THIS MORNING. HAVE ALSO ADDED ISOLATED THUNDER
FOR THIS AFTERNOON IN SOUTH AND SOUTHEAST ZONES AS HRRR AND WRF
ARW BOTH HINT AT SOME SEA BREEZE CONVECTION MAKING IT THAT FAR
NORTH.
ATMOSPHERE WILL CONTINUE TO DRY AND HAVE LEFT SATURDAY AND SUNDAY
PRECIP FREE AS THE HIGH BUILDS CLOSER TO NORTH TX. BY
MONDAY...WITH HIGH LOCATED IN MEXICO...A SERIES OF TROUGHS WILL
MOVE ACROSS THE SOUTHERN PLAINS AND HAVE THUS CONTINUED WITH THE
LOW POP CHANCES IN THE NORTH MONDAY AND TUESDAY...AND AREA WIDE
WEDNESDAY THROUGH SATURDAY MORNING.
OF INTEREST IN THE EXTENDED...BY WEDNESDAY THE ECMWF BUILDS AN
UPPER TROUGH ORIENTED NORTH/SOUTH ACROSS TEXAS AND KEEPS IT IN
PLACE THROUGH 240 HOURS. IF THIS STATIONARY TROUGH WOULD
MATERIALIZE (THE GFS BUILDS IN A RIDGE WEST AND PUSHES THE TROUGH
EAST) IT WOULD GIVE US PERIODS OF MUCH NEEDED PRECIP OVER A
NUMBER OF DAYS. ECMWF PUSHES PWATS ABOVE 2 INCHES AT DFW
WEDNESDAY AFTERNOON...BUT THE GFS LOOKS MUCH DRIER. ONE ANALOG
THAT COMES TO MIND WOULD BE THE WIDESPREAD RAIN/FLOODING THAT
OCCURRED IN JUNE 2007 WITH A SIMILAR TROUGH. AGAIN...THERE IS NO
CONSENSUS ON THIS OCCURRING SO WE CAN ONLY LOOK FOR MORE
AGREEMENT IN FUTURE GUIDANCE 84.
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 75 94 75 93 / 10 10 10 5 10
WACO, TX 91 72 93 73 92 / 10 5 10 5 10
PARIS, TX 92 72 92 72 91 / 10 10 10 5 10
DENTON, TX 93 73 93 74 93 / 10 10 10 5 10
MCKINNEY, TX 93 73 94 73 92 / 10 10 10 5 10
DALLAS, TX 93 76 94 75 93 / 10 5 10 5 10
TERRELL, TX 95 73 96 73 92 / 10 5 10 5 10
CORSICANA, TX 91 73 92 73 91 / 10 5 10 5 10
TEMPLE, TX 90 72 92 72 91 / 10 5 10 5 10
MINERAL WELLS, TX 91 72 92 73 92 / 10 5 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/58
AREA FORECAST DISCUSSION...UPDATED
NWS SAN ANGELO TX
1059 AM CDT Fri Jun 20 2014
.UPDATE...
A persistent area of showers remains across the southwestern
part of West Central Texas (mainly the Northern Edwards Plateau)
this morning. A small pocket of thunderstorms with very heavy
rainfall (near the MCV) is beginning to shift north into
southwestern Crockett County from Val Verde County. Based on radar
and satellite trends, have increased PoPs considerably for the
rest of this morning across our southwestern counties, and have
increased cloud cover in the sky condition grids. Updated forecast
products are forthcoming.
19
&&
.PREV DISCUSSION... /ISSUED 638 AM CDT FRI JUN 20 2014/
AVIATION...
/12Z TAFS/
Widespread rain showers will continue for another few hours along
the I-10 corridor, mainly affecting only KJCT and KSOA. However,
given the proximity, VCSH was retained at KSJT and BBD. There may
be some brief MVFR ceilings around 2500 ft this morning, but
abundant mid/high level clouds have obscured the low clouds. This,
combined with the overnight precipitation, will make ceilings very
difficult to forecast. If ceilings develop, they will lift above
VFR criterion by late morning. Isolated showers and thunderstorms
are in the forecast for this afternoon, along and south of a line
from KSJT to KBBD but coverage should be limited and including
thunder in the TAFs would be overkill. Have decided to leave the
forecast dry with diurnal cu dissipating around sunset. Low clouds
were included at the southern terminals tonight, mainly after 09z.
Johnson
PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 20 2014/
SHORT TERM...
(Today and tonight)
Showers, and a few thunderstorms, continue to drift to the north
and northwest across the southern half of the CWA early this
morning. This convection is the result of the enhanced lift
associated with an MCV that has developed near Del Rio and
persistent warm, moist inflow from a 30 kt low-level jet. The
latest runs of the HRRR and the TTU WRF have caught on and
continue this precipitation across the southwest quadrant of the
CWA well into the morning hours before diminishing in areal
coverage by midday. Rainfall totals have generally remain on the
light side, but a few areas have seen amounts approaching 1". The
RAWS station 10 miles south of Barnhart measured 0.91" in the past
2 hours.
Additional showers and thunderstorms will be possible this
afternoon, generally south of a Sterling City to San Saba line,
however, coverage should be limited. The NAM and RAP point
soundings indicate an uncapped environment and any residual
outflow boundaries from this morning`s activity may help initiate
diurnal storms. That said, we`ve had a very weak cap (at best) the
past several days and diurnal convection has been . Thus, only
isolated thunderstorms were mentioned for this afternoon.
The increase in cloud cover and precipitation in the area will
result in max temps a few degrees cooler than what we saw
yesterday. Highs this afternoon should range from the mid 80s in
the southwest to the lower 90s in the Big Country. We may again
see nocturnal convection across the southwest portion of the CWA.
The slight chance for precipitation was expanded slightly north
and east to account for this potential. Overnight low temperatures
will be near 70 degrees.
LONG TERM...
(Saturday through Thursday)
This weekend an upper high over southeastern Texas will begin to
weaken as an upper ridge builds into the area from the west. The
forecast area will thus continue to be under a weak mid/upper
level shear axis through Saturday with a chance of isolated
thunderstorms developing over the western CWA during the day on
Saturday and over the southern CWA Saturday night. As the western
ridge continues to build over the area on Sunday the forecast area
will come under a northwest flow aloft. Afternoon temperatures
will warm from the upper 80s and lower 90s on Saturday to the
lower to mid 90s on Sunday and a still little warmer on Monday.
As an upper short wave moves east through the Central Plains on
Tuesday it will push a weak cold into the northern Big Country by
Tuesday morning. The frontal boundary will then stall but will
provide a focus for the development of showers and thunderstorms
over the Big Country beginning Monday night and through Tuesday
night as periodic disturbances move southeast in the upper flow
aloft.
As the upper ridge continues to build over the western CONUS
through midweek and eventually over the central CONUS by the end
of the week, our forecast will be dry with afternoon highs
generally in the mid to upper 90s and morning lows in the lower
70s.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 89 71 90 71 93 / 10 10 10 10 10
San Angelo 88 70 91 71 94 / 20 20 20 10 10
Junction 86 69 90 70 92 / 30 20 10 20 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
712 AM CDT FRI JUN 20 2014
.AVIATION...
FOR THE 12Z TAFS...VFR CONDITIONS ARE EXPECTED THROUGH THE VALID
FORECAST PERIOD.
PERSISTENT...FLOODING THUNDERSTORM ACTIVITY NEAR DEL RIO HAS LEFT
A BLANKET OF UPPER LEVEL CLOUD COVER OVER ALL TAF SITES EARLY THIS
MORNING. WHILE THIS HAS NO EFFECT ON LANDING OR TAKING OFF...THIS
CLOUD LAYER PROBABLY REPRESENTS SOME TURBULENCE AT TYPICAL CRUISING
ALTITUDES BECAUSE IT WAS GENERATED BY THUNDERSTORM ACTIVITY.
OTHERWISE...THERE WERE SOME SCATTERED MVFR HEIGHT CLOUDS AROUND
CENTRAL TEXAS EARLY THIS MORNING...BUT NOTHING AROUND THE DFW AREA
AS OF 12Z. AFTER A COUPLE OF HOURS OF HEATING...A FEW TO SCATTERED
MVFR HEIGHT STRATOCUMULUS CLOUDS MAY DEVELOP. COVERAGE IS EXPECTED
TO REMAIN SCATTERED AT BEST...SO VFR CONDITIONS SHOULD HOLD.
OTHERWISE THE ONLY REAL CONCERN FOR AVIATION WEATHER IS
THUNDERSTORM CHANCES. MOST MODEL GUIDANCE ADVERTISES MID-LEVEL
SUBSIDENCE OVER AREA TAF SITES TODAY...SO HAVE NO MENTION OF
THUNDERSTORMS IN THE FORECAST AT THIS TIME. WILL MONITOR AMDAR
SOUNDINGS THROUGHOUT THE DAY TO MAKE SURE THAT THIS IS HAPPENING
AS FORECAST AS THERE SHOULD BE TELL-TALE MID-LEVEL DRYING
ASSOCIATED WITH THE SUBSIDENCE BY EARLY THIS AFTERNOON.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 312 AM CDT FRI JUN 20 2014/
UPPER LOW HAS MOVED TO SOUTHEASTERN MANITOBA...AND SHOULD START
PINWHEELING NORTH DURING THE DAY. RIDGE IS CENTERED OVER SOUTHERN
MISSISSIPPI VALLEY AND WILL SLOWLY SLIDE SOUTHWEST OVER NEXT
COUPLE OF DAYS. PWATS ARE ON THE WAY DOWN...FROM NEAR 2 INCHES
YESTERDAY TO ABOUT AN INCH AND A HALF TODAY. GUIDANCE IS
STRUGGLING WITH THE FEATURES THAT WILL DEFINE TODAY/S
WEATHER...FROM THE CURRENT CONVECTION IN SOUTHERN OKLAHOMA TO SEA
BREEZE TYPE SHOWERS MOVING IN FROM THE COAST.
AS I WRITE THIS...THE OKLAHOMA CONVECTION IS WEAKENING AND MAY BE
GONE BY 7 AM...BUT WILL KEEP A SMALL AREA OF ISOLATED THUNDER
NEAR THE RED RIVER THIS MORNING. HAVE ALSO ADDED ISOLATED THUNDER
FOR THIS AFTERNOON IN SOUTH AND SOUTHEAST ZONES AS HRRR AND WRF
ARW BOTH HINT AT SOME SEA BREEZE CONVECTION MAKING IT THAT FAR
NORTH.
ATMOSPHERE WILL CONTINUE TO DRY AND HAVE LEFT SATURDAY AND SUNDAY
PRECIP FREE AS THE HIGH BUILDS CLOSER TO NORTH TX. BY
MONDAY...WITH HIGH LOCATED IN MEXICO...A SERIES OF TROUGHS WILL
MOVE ACROSS THE SOUTHERN PLAINS AND HAVE THUS CONTINUED WITH THE
LOW POP CHANCES IN THE NORTH MONDAY AND TUESDAY...AND AREA WIDE
WEDNESDAY THROUGH SATURDAY MORNING.
OF INTEREST IN THE EXTENDED...BY WEDNESDAY THE ECMWF BUILDS AN
UPPER TROUGH ORIENTED NORTH/SOUTH ACROSS TEXAS AND KEEPS IT IN
PLACE THROUGH 240 HOURS. IF THIS STATIONARY TROUGH WOULD
MATERIALIZE (THE GFS BUILDS IN A RIDGE WEST AND PUSHES THE TROUGH
EAST) IT WOULD GIVE US PERIODS OF MUCH NEEDED PRECIP OVER A
NUMBER OF DAYS. ECMWF PUSHES PWATS ABOVE 2 INCHES AT DFW
WEDNESDAY AFTERNOON...BUT THE GFS LOOKS MUCH DRIER. ONE ANALOG
THAT COMES TO MIND WOULD BE THE WIDESPREAD RAIN/FLOODING THAT
OCCURRED IN JUNE 2007 WITH A SIMILAR TROUGH. AGAIN...THERE IS NO
CONSENSUS ON THIS OCCURRING SO WE CAN ONLY LOOK FOR MORE
AGREEMENT IN FUTURE GUIDANCE 84.
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 75 94 75 93 / 10 10 10 5 10
WACO, TX 91 72 93 73 92 / 10 5 10 5 10
PARIS, TX 92 72 92 72 91 / 10 10 10 5 10
DENTON, TX 93 73 93 74 93 / 10 10 10 5 10
MCKINNEY, TX 93 73 94 73 92 / 10 10 10 5 10
DALLAS, TX 93 76 94 75 93 / 10 5 10 5 10
TERRELL, TX 95 73 96 73 92 / 10 5 10 5 10
CORSICANA, TX 91 73 92 73 91 / 10 5 10 5 10
TEMPLE, TX 90 72 92 72 91 / 10 5 10 5 10
MINERAL WELLS, TX 91 72 92 73 92 / 10 5 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
638 AM CDT FRI JUN 20 2014
.AVIATION...
/12Z TAFS/
Widespread rain showers will continue for another few hours along
the I-10 corridor, mainly affecting only KJCT and KSOA. However,
given the proximity, VCSH was retained at KSJT and BBD. There may
be some brief MVFR ceilings around 2500 ft this morning, but
abundant mid/high level clouds have obscured the low clouds. This,
combined with the overnight precipitation, will make ceilings very
difficult to forecast. If ceilings develop, they will lift above
VFR criterion by late morning. Isolated showers and thunderstorms
are in the forecast for this afternoon, along and south of a line
from KSJT to KBBD but coverage should be limited and including
thunder in the TAFs would be overkill. Have decided to leave the
forecast dry with diurnal cu dissipating around sunset. Low clouds
were included at the southern terminals tonight, mainly after 09z.
Johnson
&&
.PREV DISCUSSION... /ISSUED 330 AM CDT FRI JUN 20 2014/
SHORT TERM...
(Today and tonight)
Showers, and a few thunderstorms, continue to drift to the north
and northwest across the southern half of the CWA early this
morning. This convection is the result of the enhanced lift
associated with an MCV that has developed near Del Rio and
persistent warm, moist inflow from a 30 kt low-level jet. The
latest runs of the HRRR and the TTU WRF have caught on and
continue this precipitation across the southwest quadrant of the
CWA well into the morning hours before diminishing in areal
coverage by midday. Rainfall totals have generally remain on the
light side, but a few areas have seen amounts approaching 1". The
RAWS station 10 miles south of Barnhart measured 0.91" in the past
2 hours.
Additional showers and thunderstorms will be possible this
afternoon, generally south of a Sterling City to San Saba line,
however, coverage should be limited. The NAM and RAP point
soundings indicate an uncapped environment and any residual
outflow boundaries from this morning`s activity may help initiate
diurnal storms. That said, we`ve had a very weak cap (at best) the
past several days and diurnal convection has been . Thus, only
isolated thunderstorms were mentioned for this afternoon.
The increase in cloud cover and precipitation in the area will
result in max temps a few degrees cooler than what we saw
yesterday. Highs this afternoon should range from the mid 80s in
the southwest to the lower 90s in the Big Country. We may again
see nocturnal convection across the southwest portion of the CWA.
The slight chance for precipitation was expanded slightly north
and east to account for this potential. Overnight low temperatures
will be near 70 degrees.
Johnson
LONG TERM...
(Saturday through Thursday)
This weekend an upper high over southeastern Texas will begin to
weaken as an upper ridge builds into the area from the west. The
forecast area will thus continue to be under a weak mid/upper
level shear axis through Saturday with a chance of isolated
thunderstorms developing over the western CWA during the day on
Saturday and over the southern CWA Saturday night. As the western
ridge continues to build over the area on Sunday the forecast area
will come under a northwest flow aloft. Afternoon temperatures
will warm from the upper 80s and lower 90s on Saturday to the
lower to mid 90s on Sunday and a still little warmer on Monday.
As an upper short wave moves east through the Central Plains on
Tuesday it will push a weak cold into the northern Big Country by
Tuesday morning. The frontal boundary will then stall but will
provide a focus for the development of showers and thunderstorms
over the Big Country beginning Monday night and through Tuesday
night as periodic disturbances move southeast in the upper flow
aloft.
As the upper ridge continues to build over the western CONUS
through midweek and eventually over the central CONUS by the end
of the week, our forecast will be dry with afternoon highs
generally in the mid to upper 90s and morning lows in the lower
70s.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 89 71 90 71 93 / 10 10 10 10 10
San Angelo 88 70 91 71 94 / 20 20 20 10 10
Junction 86 69 90 70 92 / 30 20 10 20 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
25
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
330 AM CDT FRI JUN 20 2014
.SHORT TERM...
(Today and tonight)
Showers, and a few thunderstorms, continue to drift to the north and
northwest across the southern half of the CWA early this morning.
This convection is the result of the enhanced lift associated with
an MCV that has developed near Del Rio and persistent warm, moist
inflow from a 30 kt low-level jet. The latest runs of the HRRR and
the TTU WRF have caught on and continue this precipitation across
the southwest quadrant of the CWA well into the morning hours before
diminishing in areal coverage by midday. Rainfall totals have
generally remain on the light side, but a few areas have seen
amounts approaching 1". The RAWS station 10 miles south of Barnhart
measured 0.91" in the past 2 hours.
Additional showers and thunderstorms will be possible this
afternoon, generally south of a Sterling City to San Saba line,
however, coverage should be limited. The NAM and RAP point soundings
indicate an uncapped environment and any residual outflow boundaries
from this morning`s activity may help initiate diurnal storms. That
said, we`ve had a very weak cap (at best) the past several days and
diurnal convection has been . Thus, only isolated thunderstorms
were mentioned for this afternoon.
The increase in cloud cover and precipitation in the area will
result in max temps a few degrees cooler than what we saw yesterday.
Highs this afternoon should range from the mid 80s in the southwest
to the lower 90s in the Big Country. We may again see nocturnal
convection across the southwest portion of the CWA. The slight
chance for precipitation was expanded slightly north and east to
account for this potential. Overnight low temperatures will be near
70 degrees.
Johnson
.LONG TERM...
(Saturday through Thursday)
This weekend an upper high over southeastern Texas will begin to
weaken as an upper ridge builds into the area from the west. The
forecast area will thus continue to be under a weak mid/upper level
shear axis through Saturday with a chance of isolated thunderstorms
developing over the western CWA during the day on Saturday and over
the southern CWA Saturday night. As the western ridge continues to
build over the area on Sunday the forecast area will come under a
northwest flow aloft. Afternoon temperatures will warm from the
upper 80s and lower 90s on Saturday to the lower to mid 90s on
Sunday and a still little warmer on Monday.
As an upper short wave moves east through the Central Plains on
Tuesday it will push a weak cold into the northern Big Country by
Tuesday morning. The frontal boundary will then stall but will
provide a focus for the development of showers and thunderstorms
over the Big Country beginning Monday night and through Tuesday
night as periodic disturbances move southeast in the upper flow
aloft.
As the upper ridge continues to build over the western CONUS through
midweek and eventually over the central CONUS by the end of the
week, our forecast will be dry with afternoon highs generally in
the mid to upper 90s and morning lows in the lower 70s.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 89 71 90 71 93 / 10 10 10 10 10
San Angelo 88 70 91 71 94 / 20 20 20 10 10
Junction 86 69 90 70 92 / 30 20 10 20 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
312 AM CDT FRI JUN 20 2014
.DISCUSSION...
UPPER LOW HAS MOVED TO SOUTHEASTERN MANITOBA...AND SHOULD START
PINWHEELING NORTH DURING THE DAY. RIDGE IS CENTERED OVER SOUTHERN
MISSISSIPPI VALLEY AND WILL SLOWLY SLIDE SOUTHWEST OVER NEXT
COUPLE OF DAYS. PWATS ARE ON THE WAY DOWN...FROM NEAR 2 INCHES
YESTERDAY TO ABOUT AN INCH AND A HALF TODAY. GUIDANCE IS
STRUGGLING WITH THE FEATURES THAT WILL DEFINE TODAY/S
WEATHER...FROM THE CURRENT CONVECTION IN SOUTHERN OKLAHOMA TO SEA
BREEZE TYPE SHOWERS MOVING IN FROM THE COAST.
AS I WRITE THIS...THE OKLAHOMA CONVECTION IS WEAKENING AND MAY BE
GONE BY 7 AM...BUT WILL KEEP A SMALL AREA OF ISOLATED THUNDER
NEAR THE RED RIVER THIS MORNING. HAVE ALSO ADDED ISOLATED THUNDER
FOR THIS AFTERNOON IN SOUTH AND SOUTHEAST ZONES AS HRRR AND WRF
ARW BOTH HINT AT SOME SEA BREEZE CONVECTION MAKING IT THAT FAR
NORTH.
ATMOSPHERE WILL CONTINUE TO DRY AND HAVE LEFT SATURDAY AND SUNDAY
PRECIP FREE AS THE HIGH BUILDS CLOSER TO NORTH TX. BY
MONDAY...WITH HIGH LOCATED IN MEXICO...A SERIES OF TROUGHS WILL
MOVE ACROSS THE SOUTHERN PLAINS AND HAVE THUS CONTINUED WITH THE
LOW POP CHANCES IN THE NORTH MONDAY AND TUESDAY...AND AREA WIDE
WEDNESDAY THROUGH SATURDAY MORNING.
OF INTEREST IN THE EXTENDED...BY WEDNESDAY THE ECMWF BUILDS AN
UPPER TROUGH ORIENTED NORTH/SOUTH ACROSS TEXAS AND KEEPS IT IN
PLACE THROUGH 240 HOURS. IF THIS STATIONARY TROUGH WOULD
MATERIALIZE (THE GFS BUILDS IN A RIDGE WEST AND PUSHES THE TROUGH
EAST) IT WOULD GIVE US PERIODS OF MUCH NEEDED PRECIP OVER A
NUMBER OF DAYS. ECMWF PUSHES PWATS ABOVE 2 INCHES AT DFW
WEDNESDAY AFTERNOON...BUT THE GFS LOOKS MUCH DRIER. ONE ANALOG
THAT COMES TO MIND WOULD BE THE WIDESPREAD RAIN/FLOODING THAT
OCCURRED IN JUNE 2007 WITH A SIMILAR TROUGH. AGAIN...THERE IS NO
CONSENSUS ON THIS OCCURRING SO WE CAN ONLY LOOK FOR MORE
AGREEMENT IN FUTURE GUIDANCE 84.
&&
.AVIATION...
/ISSUED 1142 PM CDT THU JUN 19 2014/
/6Z TAFS/
VFR CONDITIONS PREVAIL AREA WIDE LATE THIS EVENING WITH SOME
SCT/BKN HIGH CLOUD SPREADING IN ACROSS THE REGION. SCATTERED
SHOWERS AND THUNDERSTORMS ARE ONGOING ACROSS PARTS OF SOUTH
CENTRAL OKLAHOMA AND ARE MOVING TOWARD THE RED RIVER. REGIONAL
RADAR IMAGERY SHOWS A SUBSTANTIAL OUTFLOW BOUNDARY ALREADY PUSHING
OUT AHEAD OF THESE STORMS...SO THINKING IS THEY WILL CONTINUE TO
WEAKEN AS THEY MOVE INTO NORTH TEXAS. FOR NOW...WILL LEAVE ANY
PRECIP OUT OF THE METROPLEX TAFS. OTHERWISE...SOME SCT LOW CLOUDS
MAY MOVE INTO THE AREA EARLY FRIDAY MORNING WITH TEMPO MVFR CIGS
AT WACO.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 94 75 94 75 93 / 10 10 10 5 10
WACO, TX 91 72 93 73 92 / 10 5 10 5 10
PARIS, TX 92 72 92 72 91 / 10 10 10 5 10
DENTON, TX 93 73 93 74 93 / 10 10 10 5 10
MCKINNEY, TX 93 73 94 73 92 / 10 10 10 5 10
DALLAS, TX 93 76 94 75 93 / 10 5 10 5 10
TERRELL, TX 95 73 96 73 92 / 10 5 10 5 10
CORSICANA, TX 91 73 92 73 91 / 10 5 10 5 10
TEMPLE, TX 90 72 92 72 91 / 10 5 10 5 10
MINERAL WELLS, TX 91 72 92 73 92 / 10 5 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1140 PM CDT Thu Jun 19 2014
.AVIATION...
/06Z TAFS/
Scattered showers are developing northward into the northern Edwards
Plateau late this evening, approaching the southern terminals of
Sonora, Junction, and Brady (KSOA/KJCT/KBBD). Its still pretty
spotty and light so far, with the bulk of the more concentrated
heavier rainfall likely to remain south of the area. To the north,
additional storms are moving across the South Plains and may
approach Abilene (KABI), but the majority looks to remain north.
Which means for the most part, we are dealing with the arrival the
same MVFR cigs we have seen the last few nights and their departure
around mid to late morning. Convection will effect timing, but
exactly how is a question. Will start with roughly the same timing
as have been using and see how it works.
&&
.PREV DISCUSSION... /ISSUED 1106 PM CDT THU JUN 19 2014/
UPDATE...
Increased rainfall chances across southwest sections overnight.
DISCUSSION...
Shower activity is beginning to increase in coverage south of I-10
across Val Verde and Edwards counties, with a few showers also
developing in southern Sutton county. A persistent area of very
heavy rainfall has been ongoing this evening southeast of Del Rio.
This activity is in association with a remnant MCV that is drifting
slowly northwest. Latest model data, including the HRRR and Texas
Tech WRF expand convection northwest across the North Edwards
Plateau overnight in conjunction with the northwest propagating MCV
and a strengthening 850 mb low level jet. Precipitable waters are
running around 1.7 inches and will contribute to heavy rainfall
potential across the said area. Ramped up POPs to likely across
Crockett, Sutton and southwest Schleicher county overnight and will
continue to mention locally heavy rainfall across this area. Current
thinking is that the best Flash Flood threat will be farther south
across the Edwards Plateau where current convective complex will be
very slow moving overnight. Will continue to monitor convective
trends through the night.
Another area of convection is moving east/southeast across the
Texas South Plains east of Lubbock. This activity will make a run
at northwest counties after midnight but outflow is currently
outrunning the convection and will likely result in some weakening
as it continues southeast. Have increases POPs to 30 percent
across the northwestern Big Country to account for this uncertainty.
Also tweaked temperatures and dewpoints to account for trends.
PREV DISCUSSION... /ISSUED 621 PM CDT THU JUN 19 2014/
AVIATION...
/00Z TAFS/
Messy forecast across the West Central Texas terminals over the next
24 hours, with a great deal of uncertainty. Weak system pushing
northward up the Rio Grande may allow storms to redevelop and become
more widespread across much of the area by around might and continue
into the early morning hours. But not certain they will develop at
all. To the west, a complex of storms will likely develop across the
Panhandle and South Plains and push east this evening. But whether
they reach Abilene, KABI, remains a huge question as well. For right
now, will base the forecast on persistence from the last 24 to 48
hours, and add a VCTS mention to the forecast for the southernmost
sites of Sonora/Junction/Brady where the storms seem most likely
overnight.
PREV DISCUSSION... /ISSUED 409 PM CDT THU JUN 19 2014/
SHORT TERM...
(Tonight and Friday)
Have a developing concern for heavy rainfall potential across
our southern and possibly some central counties tonight. This
is in association with a compact MCV, which appears on satellite
imagery near Eagle Pass along the Rio Grande. This feature will
move north-northwest and should enter our far southern counties
(Sutton or Crockett Counties) toward Midnight. Low-level jet
developing tonight will aid in low-level moisture transport.
The Satellite Precipitation Estimates product from the NESDIS
Satellite Analysis Branch has more details on the potential for
locally heavy rain with this feature. Have increased PoPs across
much of the southern half of our area, with a mention of locally
heavy rainfall. The HRRR and TTU WRF both show development
of convection across our soutern and some of our central counties
tonight. PoPs may need to be raised further as radar trends
become more apparent.
To the northwest of our area, a gravity wave entering northwestern
Texas ahead of a cold front could initiate thunderstorms late this
afternoon and evening. The HRRR and TTU WRF models show a band of
convection approaching our northwestern counties after 9 PM. With
uncertainty in how much shower/thunderstorm coverage will occur
away from the MCV, carrying lower PoPs across the rest of our area
tonight.
For Friday, carring low PoPs across West Central Texas. Models show
a mid/upper level shear axis over our area, with precipitable water
values between 1 and 1.6 inches. Little change in the temperature
regime is expected.
LONG TERM...
(Friday night through next Thursday)
Our area will remain under a weak mid/upper level shear axis through
Saturday, as upper ridge begins to build over northwest Mexico into
the Desert Southwest, and the upper high weakens over the lower
Mississippi Valley. Have a slight chance PoP lingering across our
western counties on Saturday.
During the first half of next week, the upper high is progged to
build over northwestern Mexico and the southwestern U.S., and weak
northwest flow aloft will develop over our area. The forecast 850 mb
temperatures indicate a gradual warming trend with daytime
temperatures for our area. Weak surface cold front is progged to sag
south of the Red River and stall Tuesday evening, The 12Z GFS
suggests potential for convective complext to approach our area from
the northwest Tuesday night. Did not make changes to our PoPs next
week, but will monitor model trends.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 71 90 72 91 72 / 20 20 5 10 10
San Angelo 71 91 72 92 72 / 30 20 10 10 10
Junction 72 90 71 91 71 / 40 20 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1106 PM CDT THU JUN 19 2014
.UPDATE...
Increased rainfall chances across southwest sections overnight.
&&
.DISCUSSION...
Shower activity is beginning to increase in coverage south of I-10
across Val Verde and Edwards counties, with a few showers also
developing in southern Sutton county. A persistent area of very
heavy rainfall has been ongoing this evening southeast of Del Rio.
This activity is in association with a remnant MCV that is drifting
slowly northwest. Latest model data, including the HRRR and Texas
Tech WRF expand convection northwest across the North Edwards
Plateau overnight in conjunction with the northwest propagating MCV
and a strengthening 850 mb low level jet. Precipitable waters are
running around 1.7 inches and will contribute to heavy rainfall
potential across the said area. Ramped up POPs to likely across
Crockett, Sutton and southwest Schleicher county overnight and will
continue to mention locally heavy rainfall across this area. Current
thinking is that the best Flash Flood threat will be farther south
across the Edwards Plateau where current convective complex will be
very slow moving overnight. Will continue to monitor convective
trends through the night.
Another area of convection is moving east/southeast across the
Texas South Plains east of Lubbock. This activity will make a run
at northwest counties after midnight but outflow is currently
outrunning the convection and will likely result in some weakening
as it continues southeast. Have increases POPs to 30 percent
across the northwestern Big Country to account for this uncertainty.
Also tweaked temperatures and dewpoints to account for trends.
&&
.PREV DISCUSSION... /ISSUED 621 PM CDT THU JUN 19 2014/
AVIATION...
/00Z TAFS/
Messy forecast across the West Central Texas terminals over the next
24 hours, with a great deal of uncertainty. Weak system pushing
northward up the Rio Grande may allow storms to redevelop and become
more widespread across much of the area by around might and continue
into the early morning hours. But not certain they will develop at
all. To the west, a complex of storms will likely develop across the
Panhandle and South Plains and push east this evening. But whether
they reach Abilene, KABI, remains a huge question as well. For right
now, will base the forecast on persistence from the last 24 to 48
hours, and add a VCTS mention to the forecast for the southernmost
sites of Sonora/Junction/Brady where the storms seem most likely
overnight.
PREV DISCUSSION... /ISSUED 409 PM CDT THU JUN 19 2014/
SHORT TERM...
(Tonight and Friday)
Have a developing concern for heavy rainfall potential across
our southern and possibly some central counties tonight. This
is in association with a compact MCV, which appears on satellite
imagery near Eagle Pass along the Rio Grande. This feature will
move north-northwest and should enter our far southern counties
(Sutton or Crockett Counties) toward Midnight. Low-level jet
developing tonight will aid in low-level moisture transport.
The Satellite Precipitation Estimates product from the NESDIS
Satellite Analysis Branch has more details on the potential for
locally heavy rain with this feature. Have increased PoPs across
much of the southern half of our area, with a mention of locally
heavy rainfall. The HRRR and TTU WRF both show development
of convection across our soutern and some of our central counties
tonight. PoPs may need to be raised further as radar trends
become more apparent.
To the northwest of our area, a gravity wave entering northwestern
Texas ahead of a cold front could initiate thunderstorms late this
afternoon and evening. The HRRR and TTU WRF models show a band of
convection approaching our northwestern counties after 9 PM. With
uncertainty in how much shower/thunderstorm coverage will occur
away from the MCV, carrying lower PoPs across the rest of our area
tonight.
For Friday, carring low PoPs across West Central Texas. Models show
a mid/upper level shear axis over our area, with precipitable water
values between 1 and 1.6 inches. Little change in the temperature
regime is expected.
LONG TERM...
(Friday night through next Thursday)
Our area will remain under a weak mid/upper level shear axis through
Saturday, as upper ridge begins to build over northwest Mexico into
the Desert Southwest, and the upper high weakens over the lower
Mississippi Valley. Have a slight chance PoP lingering across our
western counties on Saturday.
During the first half of next week, the upper high is progged to
build over northwestern Mexico and the southwestern U.S., and weak
northwest flow aloft will develop over our area. The forecast 850 mb
temperatures indicate a gradual warming trend with daytime
temperatures for our area. Weak surface cold front is progged to sag
south of the Red River and stall Tuesday evening, The 12Z GFS
suggests potential for convective complext to approach our area from
the northwest Tuesday night. Did not make changes to our PoPs next
week, but will monitor model trends.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 71 90 72 91 72 / 20 20 5 10 10
San Angelo 71 91 72 92 72 / 30 20 10 10 10
Junction 72 90 71 91 71 / 40 20 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
24
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
116 PM EDT FRI JUN 20 2014
.SYNOPSIS...
A WARM FRONT TRAILED FROM THE OHIO VALLEY DOWN ACROSS THE NEW
RIVER VALLEY EARLY THIS AFTERNOON. THIS FRONT WILL LIFT NORTHEAST
OF THE AREA THIS AFTERNOON. LOW PRESSURE WILL MOVE ALONG THIS
FRONT...THROUGH THE OHIO VALLEY TONIGHT...THEN INTO VIRGINIA ON
SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 115 PM EDT FRIDAY...
A WARM FRONT REMAINS OVER THE FORECAST AREA AND WILL TRACK SLOWLY
TO THE NORTHEAST THIS AFTERNOON. THIS WARM FRONT IS ORIENTED FROM
NW TO SE AND IS PRODUCING SCATTERED SHOWERS ACROSS THE MOUNTAINS
EARLY THIS AFTERNOON. THESE STORMS WILL CONTINUE TO TRACK NW TO
SE THROUGH THE EARLY EVENING. AS THE WARM FRONT SHIFTS
NORTH...SCATTERED SHOWER ACTIVITY WILL ALSO ADVANCE NORTH ACROSS
THE ENTIRE AREA.
MODEST CAPE VALUES ARE CURRENTLY BEING HELD DOWN BY CLOUD COVER.
THIS CLOUD COVER WILL THIN OUT THROUGH THE DAY...WHICH WILL THEN
INCREASE INSTABILITIES AS HEATING IS MAXIMIZED. VERTICAL SHEAR IS
MARGINAL BUT INSTABILITIES WILL BE ENOUGH TO PRODUCE A FEW STRONG
TO SEVERE MULTICELLAR STORMS THIS AFTERNOON AND INTO THIS EVENING.
CONVECTION WILL FADE SOME WITH LOSE OF HEATING BUT ONLY TO GIVE
WAY TO A MESOSCALE SYSTEM ENTERING THE AREA FROM THE OHIO VALLEY
LATER TONIGHT. SPC HAS UPGRADED THE SOUTHERN OHIO VALLEY TO A
SLIGHT RISK. EXPECT THIS SLIGHT RISK TO MOVE EASTWARD AS THE MCS
CONTINUES TO STRENGTHEN AND SHOWS IT TRUE PATH.
AS OF 400 AM EDT FRIDAY...
WARM FRONT...MAINLY INDICATED AROUND 850 MB...ACROSS THE OHIO VALLEY
WILL BRING SOME WARM AIR ADVECTION AND KEEP DEEPER MOISTURE IN THE
AREA TODAY. AGAIN EXPECTING SCATTERED THUNDERSTORMS THIS AFTERNOON.
SIMILAR TO THURSDAY...HIGH CLOUDS WILL CUT BACK ON HEATING IN THE
MORNING AND THEREFORE THE AMOUNT OF INSTABILITY IN THE AFTERNOON.
STILL ENOUGH CAPE...FORECAST TO BE AROUND 1500 J/KG...FOR A THREAT
OF STRONGER THUNDERSTORMS BEFORE 00Z/8PM. HRRR BRINGS PRECIPITATION
IN TO THE FORECAST AROUND 17Z/1PM.
MODELS HAVE BEEN TRENDED COOLER WITH MAXIMUM TEMPERATURES FOR TODAY.
HIGH WILL DEPEND ON HOW MUCH HIGH CLOUDS FROM THIS MORNING CAN ERODE
BEFORE THUNDERSTORMS DEVELOP.
SHORT WAVE OVER ILLINOIS AND INDIANA WILL MOVE SOUTHEAST...REACHING
WESTERN PARTS OF THE FORECAST AREA JUST AFTER 00Z AND SLOWLY MOVING
ACROSS THE COUNTY WARNING AREA OVERNIGHT. HAVE INCREASED
PROBABILITY OF PRECIPITATION TONIGHT WITH HIGHEST PROBABILITY AFTER
MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 320 AM EDT FRIDAY...
LOW PRESSURE WILL TRACK SOUTHEAST FROM NORTHERN WEST VIRGINIA
SATURDAY MORNING AND REACHES EASTERN VIRGINIA BY SATURDAY AFTERNOON.
THE NAM...GFS AND ECMWF SUPPORT GOOD COVERAGE OF SHOWERS AND
THUNDERSTORMS SATURDAY AS DISTURBANCE TRACKS EASTWARD ALONG THE
THETA-E BOUNDARY. INCREASED POPS FOR SATURDAY ESPECIALLY SATURDAY
MORNING. SPC SWODY2 HAS PLACED THE SLIGHT RISK OF SEVERE
THUNDERSTORMS ACROSS THE CENTRAL PLAINS WITH A SEE TEXT IN EASTERN
CAROLINAS. WITH ADDITIONAL CLOUD COVER AND PRECIPITATION
SATURDAY...LOWERED HIGH TEMPERATURES WITH READINGS FROM THE UPPER
70S IN THE MOUNTAINS TO UPPER 80S IN THE PIEDMONT. AFTER THE
DISTURBANCE EXITS THE AREA SATURDAY EVENING...A SLIGHT COOLER AND
DRY AIRMASS WILL TEMPORARY BUILD OVER THE REGION SATURDAY NIGHT. LOW
TEMPERATURES SATURDAY NIGHT WILL RANGE FROM AROUND 60 DEGREES IN THE
WEST TO THE MID 60S IN THE EAST.
SFC HIGH PRESSURE PROGGED TO BE CENTERED EAST SOUTHEAST OF NEW
ENGLAND ON SUNDAY...AND SLOWLY BUILDS SOUTHWARD. DECREASED POPS FOR
SUNDAY AS A NORTHERLY FLOW AND LESS INSTABILITIES SHOULD LEAD TO
LESS CONVECTION. WITH CAUTION...HELD ON TO SCATTERED AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS. THE GFS WAS MORE ROBUST WITH
CONVECTION COMPARED TO ECMWF AND NAM FOR SUNDAY. WENT WITH HIGH
TEMPERATURES SUNDAY FROM THE UPPER 70S IN THE MOUNTAINS TO THE MID
80S IN THE PIEDMONT. SOUTHEASTERLY FLOW OVERNIGHT SUNDAY MAY KEEP A
FEW SHOWERS ONGOING INTO EARLY MONDAY MORNING. THE BEST CHANCE FOR
SHOWERS SUNDAY NIGHT WILL OCCUR ALONG THE SOUTHERN BLUE RIDGE
MOUNTAINS. LOWS SUNDAY NIGHT WILL GENERALLY BE IN THE 60S.
LEANED TOWARDS HPCGUIDE FOR MONDAY WITH PULSE STORM AND THE PRIMARY
FOCUS FOR CONVECTION ACROSS THE MOUNTAINS. TAPER OFF SCATTERED
STORMS TO ISOLATED SHOWERS MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM EDT THURSDAY...
TUESDAY COULD BE A MIX OF CONVECTION FROM PULSE STORMS IN THE EARLY
AFTERNOON TRANSITIONING TO PREFRONTAL CONVECTION IN THE EARLY
EVENING THROUGH THE EARLY MORNING HOURS. ON WEDNESDAY...A COLD FRONT
WILL SLIDE ACROSS THE REGION WITH THE BEST AREAL COVERAGE OF THE
STRONGER STORMS BEING ACROSS THE PIEDMONT. THE COLD FRONT MAY
WASHOUT OR STALL WITH THE DEW POINT FRONT HANGING BACK ACROSS THE
OHIO VALLEY. UNDER HEATING...SCATTERED CONVECTION MAY FIRE AGAIN
ACROSS THE AREA THURSDAY ESPECIALLY ALONG AND SOUTH OF THE VA/NC
BORDER.
&&
.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
AS OF 115 PM EDT FRIDAY...
PATCHES MVFR CLOUDS WILL LIFT EARLY THIS AFTERNOON AS A WARM
FRONT MOVES NORTH OF THE FORECAST AREA. ENOUGH HEATING AND DECENT
INSTABILITY FOR SHOWERS AND THUNDERSTORMS TO DEVELOP THROUGH THE
AFTERNOON. SLOW MOVING NW TO SE TRACKING STORMS EXPECTED AT
BLF/LWB BETWEEN 19Z/2P-02Z/10. HIT AND MISS THUNDERSTORMS EXPECTED
ACROSS THE AREA WHILE CONFIDENCE FOR A STORM TO BE IN THE VICINITY
OF KROA/KBCB/KLYH/KDAN AT A GIVEN TIME IS VERY LOW.
A STRONGER SHORT WAVE WILL REACH THE FORECAST AREA TONIGHT. HAVE
KEPT CEILINGS VFR AT KROA/KBCB/KLYH AND KDAN WITH SHOWERS...MAINLY
AFTER 05Z/1AM SATURDAY. MODERATE CONFIDENCE OF MVFR CEILINGS FOR
KLWB/KBLF WITH A PROLONGED PERIOD OF SHOWERS AND EMBEDDED
THUNDERSTORMS OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
A WEAK FLOW PATTERN HOLDING OVER THE WEEKEND WILL KEEP THE STORM
CHANCES EACH AFTERNOON THROUGH EARLY EVENING SAT/SUN BUT COVERAGE
FOR NOW LOOKS A BIT LESS EACH DAY BEHIND THE PASSING IMPULSE FROM
SATURDAY MORNING. DEEPER MOISTURE LOOKS TO RETURN NORTH BY EARLY
NEXT WEEK WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON
MONDAY.
AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING...
PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. THE
MOST OPTIMAL FLIGHT CONDITIONS EACH DAY SHOULD BE IN THE MID TO
LATE MORNING AFTER FOG/LOW CLOUDS LIFT AND BURN OFF...AND BEFORE
AFTERNOON CONVECTION REDEVELOPS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/RCS
SHORT TERM...KK
LONG TERM...RCS
AVIATION...RCS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1054 AM EDT FRI JUN 20 2014
.SYNOPSIS...
A WARM FRONT TRAILED FROM MINNESOTA TO KENTUCKY THIS MORNING.
THIS FRONT WILL LIFT NORTHEAST INTO THE AREA TODAY. LOW PRESSURE
WILL MOVE ALONG THIS FRONT...THROUGH THE OHIO VALLEY TONIGHT...THEN
INTO VIRGINIA ON SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 AM EDT FRIDAY...
A WARM FRONT REMAINS OVER THE FORECAST AREA THIS MORNING AND WILL
TRACK SLOWLY TO THE NORTHEAST TODAY. THIS WARM FRONT IS ORIENTEDFROM
NW TO SE AND IS PRODUCING SCATTERED SHOWERS FROM RICHLANDS AND
ACROSS THE MOUNTAIN EMPIRE THIS MORNING. THESE STORMS WILL
CONTINUE TO TRACK NW TO SE THROUGH THE AFTERNOON. AS THE WARM
FRONT SHIFTS NORTH...SCATTERED SHOWER ACTIVITY WILL ALSO ADVANCE
NORTH ACROSS THE AREA.
MODEST CAPE VALUES ARE CURRENTLY BEING HELD DOWN WITH MORNING
CLOUD COVER. THIS CLOUD COVER WILL THIN OUT THROUGH THE
DAY...WHICH WILL THEN INCREASE INSTABILITIES AS HEATING IS
MAXIMIZED. VERTICAL SHEAR IS MARGINAL BUT INSTABILITIES WILL BE
ENOUGH TO PRODUCE A FEW STRONG TO SEVERE MULTICELLAR STORMS THIS
AFTERNOON AND INTO THIS EVENING. CONVECTION WILL FADE SOME WITH
LOSE OF HEATING BUT ONLY TO GIVE WAY TO A MESOSCALE SYSTEM
ENTERING THE AREA FROM THE OHIO VALLEY LATER TONIGHT.
AS OF 400 AM EDT FRIDAY...
WARM FRONT...MAINLY INDICATED AROUND 850 MB...ACROSS THE OHIO VALLEY
WILL BRING SOME WARM AIR ADVECTION AND KEEP DEEPER MOISTURE IN THE
AREA TODAY. AGAIN EXPECTING SCATTERED THUNDERSTORMS THIS AFTERNOON.
SIMILAR TO THURSDAY...HIGH CLOUDS WILL CUT BACK ON HEATING IN THE
MORNING AND THEREFORE THE AMOUNT OF INSTABILITY IN THE AFTERNOON.
STILL ENOUGH CAPE...FORECAST TO BE AROUND 1500 J/KG...FOR A THREAT
OF STRONGER THUNDERSTORMS BEFORE 00Z/8PM. HRRR BRINGS PRECIPITATION
IN TO THE FORECAST AROUND 17Z/1PM.
MODELS HAVE BEEN TRENDED COOLER WITH MAXIMUM TEMPERATURES FOR TODAY.
HIGH WILL DEPEND ON HOW MUCH HIGH CLOUDS FROM THIS MORNING CAN ERODE
BEFORE THUNDERSTORMS DEVELOP.
SHORT WAVE OVER ILLINOIS AND INDIANA WILL MOVE SOUTHEAST...REACHING
WESTERN PARTS OF THE FORECAST AREA JUST AFTER 00Z AND SLOWLY MOVING
ACROSS THE COUNTY WARNING AREA OVERNIGHT. HAVE INCREASED
PROBABILITY OF PRECIPITATION TONIGHT WITH HIGHEST PROBABILITY AFTER
MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 320 AM EDT FRIDAY...
LOW PRESSURE WILL TRACK SOUTHEAST FROM NORTHERN WEST VIRGINIA
SATURDAY MORNING AND REACHES EASTERN VIRGINIA BY SATURDAY AFTERNOON.
THE NAM...GFS AND ECMWF SUPPORT GOOD COVERAGE OF SHOWERS AND
THUNDERSTORMS SATURDAY AS DISTURBANCE TRACKS EASTWARD ALONG THE
THETA-E BOUNDARY. INCREASED POPS FOR SATURDAY ESPECIALLY SATURDAY
MORNING. SPC SWODY2 HAS PLACED THE SLIGHT RISK OF SEVERE
THUNDERSTORMS ACROSS THE CENTRAL PLAINS WITH A SEE TEXT IN EASTERN
CAROLINAS. WITH ADDITIONAL CLOUD COVER AND PRECIPITATION
SATURDAY...LOWERED HIGH TEMPERATURES WITH READINGS FROM THE UPPER
70S IN THE MOUNTAINS TO UPPER 80S IN THE PIEDMONT. AFTER THE
DISTURBANCE EXITS THE AREA SATURDAY EVENING...A SLIGHT COOLER AND
DRY AIRMASS WILL TEMPORARY BUILD OVER THE REGION SATURDAY NIGHT. LOW
TEMPERATURES SATURDAY NIGHT WILL RANGE FROM AROUND 60 DEGREES IN THE
WEST TO THE MID 60S IN THE EAST.
SFC HIGH PRESSURE PROGGED TO BE CENTERED EAST SOUTHEAST OF NEW
ENGLAND ON SUNDAY...AND SLOWLY BUILDS SOUTHWARD. DECREASED POPS FOR
SUNDAY AS A NORTHERLY FLOW AND LESS INSTABILITIES SHOULD LEAD TO
LESS CONVECTION. WITH CAUTION...HELD ON TO SCATTERED AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS. THE GFS WAS MORE ROBUST WITH
CONVECTION COMPARED TO ECMWF AND NAM FOR SUNDAY. WENT WITH HIGH
TEMPERATURES SUNDAY FROM THE UPPER 70S IN THE MOUNTAINS TO THE MID
80S IN THE PIEDMONT. SOUTHEASTERLY FLOW OVERNIGHT SUNDAY MAY KEEP A
FEW SHOWERS ONGOING INTO EARLY MONDAY MORNING. THE BEST CHANCE FOR
SHOWERS SUNDAY NIGHT WILL OCCUR ALONG THE SOUTHERN BLUE RIDGE
MOUNTAINS. LOWS SUNDAY NIGHT WILL GENERALLY BE IN THE 60S.
LEANED TOWARDS HPCGUIDE FOR MONDAY WITH PULSE STORM AND THE PRIMARY
FOCUS FOR CONVECTION ACROSS THE MOUNTAINS. TAPER OFF SCATTERED
STORMS TO ISOLATED SHOWERS MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM EDT THURSDAY...
TUESDAY COULD BE A MIX OF CONVECTION FROM PULSE STORMS IN THE EARLY
AFTERNOON TRANSITIONING TO PREFRONTAL CONVECTION IN THE EARLY
EVENING THROUGH THE EARLY MORNING HOURS. ON WEDNESDAY...A COLD FRONT
WILL SLIDE ACROSS THE REGION WITH THE BEST AREAL COVERAGE OF THE
STRONGER STORMS BEING ACROSS THE PIEDMONT. THE COLD FRONT MAY
WASHOUT OR STALL WITH THE DEW POINT FRONT HANGING BACK ACROSS THE
OHIO VALLEY. UNDER HEATING...SCATTERED CONVECTION MAY FIRE AGAIN
ACROSS THE AREA THURSDAY ESPECIALLY ALONG AND SOUTH OF THE VA/NC
BORDER.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AS OF 735 AM EDT FRIDAY...
PATCHES MVFR TO IFR CLOUDS WILL LIFT THIS MORNING WITH ALL TAF
SITES VFR BY 14Z/10AM. ENOUGH HEATING AND DECENT INSTABILITY BY
NOON/16Z FOR SHOWERS AND THUNDERSTORMS TO DEVELOP AS A WARM FRONT
MOVES INTO THE AREA FROM THE OHIO VALLEY.
A STRONGER SHORT WAVE WILL REACH THE FORECAST AREA TONIGHT. HAVE
KEPT CEILINGS VFR AT KROA/KBCB AND KDAN WITH SHOWERS...MAINLY
AFTER 02Z/10PM. MODERATE CONFIDENCE OF MVFR CEILINGS FOR
KLYH/KLWB/KBLF WITH A PROLONGED PERIOD OF SHOWERS AND EMBEDDED
THUNDERSTORMS OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
A WEAK FLOW PATTERN HOLDING OVER THE WEEKEND WILL KEEP THE STORM
CHANCES EACH AFTERNOON THROUGH EARLY EVENING SAT/SUN BUT COVERAGE
FOR NOW LOOKS A BIT LESS EACH DAY BEHIND THE PASSING IMPULSE FROM
FRIDAY NIGHT. DEEPER MOISTURE LOOKS TO RETURN NORTH BY EARLY NEXT
WEEK WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON MONDAY.
AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING...
PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. THE
MOST OPTIMAL FLIGHT CONDITIONS EACH DAY SHOULD BE IN THE MID TO
LATE MORNING AFTER FOG/LOW CLOUDS LIFT AND BURN OFF...AND BEFORE
AFTERNOON CONVECTION REDEVELOPS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/RCS
SHORT TERM...KK
LONG TERM...RCS
AVIATION...AMS/PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
740 AM EDT FRI JUN 20 2014
.SYNOPSIS...
A WARM FRONT TRAILED FROM MINNESOTA TO KENTUCKY THIS MORNING.
THIS FRONT WILL LIFT NORTHEAST INTO THE AREA TODAY. LOW PRESSURE
WILL MOVE ALONG THIS FRONT...THROUGH THE OHIO VALLEY TONIGHT...THEN
INTO VIRGINIA ON SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EDT FRIDAY...
WARM FRONT...MAINLY INDICATED AROUND 850 MB...ACROSS THE OHIO VALLEY
WILL BRING SOME WARM AIR ADVECTION AND KEEP DEEPER MOISTURE IN THE
AREA TODAY. AGAIN EXPECTING SCATTERED THUNDERSTORMS THIS AFTERNOON.
SIMILAR TO THURSDAY...HIGH CLOUDS WILL CUT BACK ON HEATING IN THE
MORNING AND THEREFORE THE AMOUNT OF INSTABILITY IN THE AFTERNOON.
STILL ENOUGH CAPE...FORECAST TO BE AROUND 1500 J/KG...FOR A THREAT
OF STRONGER THUNDERSTORMS BEFORE 00Z/8PM. HRRR BRINGS PRECIPITATION
IN TO THE FORECAST AROUND 17Z/1PM.
MODELS HAVE BEEN TRENDED COOLER WITH MAXIMUM TEMPERATURES FOR TODAY.
HIGH WILL DEPEND ON HOW MUCH HIGH CLOUDS FROM THIS MORNING CAN ERODE
BEFORE THUNDERSTORMS DEVELOP.
SHORT WAVE OVER ILLINOIS AND INDIANA WILL MOVE SOUTHEAST...REACHING
WESTERN PARTS OF THE FORECAST AREA JUST AFTER 00Z AND SLOWLY MOVING
ACROSS THE COUNTY WARNING AREA OVERNIGHT. HAVE INCREASED
PROBABILITY OF PRECIPITATION TONIGHT WITH HIGHEST PROBABILITY AFTER
MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 320 AM EDT FRIDAY...
LOW PRESSURE WILL TRACK SOUTHEAST FROM NORTHERN WEST VIRGINIA
SATURDAY MORNING AND REACHES EASTERN VIRGINIA BY SATURDAY AFTERNOON.
THE NAM...GFS AND ECMWF SUPPORT GOOD COVERAGE OF SHOWERS AND
THUNDERSTORMS SATURDAY AS DISTURBANCE TRACKS EASTWARD ALONG THE
THETA-E BOUNDARY. INCREASED POPS FOR SATURDAY ESPECIALLY SATURDAY
MORNING. SPC SWODY2 HAS PLACED THE SLIGHT RISK OF SEVERE
THUNDERSTORMS ACROSS THE CENTRAL PLAINS WITH A SEE TEXT IN EASTERN
CAROLINAS. WITH ADDITIONAL CLOUD COVER AND PRECIPITATION
SATURDAY...LOWERED HIGH TEMPERATURES WITH READINGS FROM THE UPPER
70S IN THE MOUNTAINS TO UPPER 80S IN THE PIEDMONT. AFTER THE
DISTURBANCE EXITS THE AREA SATURDAY EVENING...A SLIGHT COOLER AND
DRY AIRMASS WILL TEMPORARY BUILD OVER THE REGION SATURDAY NIGHT. LOW
TEMPERATURES SATURDAY NIGHT WILL RANGE FROM AROUND 60 DEGREES IN THE
WEST TO THE MID 60S IN THE EAST.
SFC HIGH PRESSURE PROGGED TO BE CENTERED EAST SOUTHEAST OF NEW
ENGLAND ON SUNDAY...AND SLOWLY BUILDS SOUTHWARD. DECREASED POPS FOR
SUNDAY AS A NORTHERLY FLOW AND LESS INSTABILITIES SHOULD LEAD TO
LESS CONVECTION. WITH CAUTION...HELD ON TO SCATTERED AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS. THE GFS WAS MORE ROBUST WITH
CONVECTION COMPARED TO ECMWF AND NAM FOR SUNDAY. WENT WITH HIGH
TEMPERATURES SUNDAY FROM THE UPPER 70S IN THE MOUNTAINS TO THE MID
80S IN THE PIEDMONT. SOUTHEASTERLY FLOW OVERNIGHT SUNDAY MAY KEEP A
FEW SHOWERS ONGOING INTO EARLY MONDAY MORNING. THE BEST CHANCE FOR
SHOWERS SUNDAY NIGHT WILL OCCUR ALONG THE SOUTHERN BLUE RIDGE
MOUNTAINS. LOWS SUNDAY NIGHT WILL GENERALLY BE IN THE 60S.
LEANED TOWARDS HPCGUIDE FOR MONDAY WITH PULSE STORM AND THE PRIMARY
FOCUS FOR CONVECTION ACROSS THE MOUNTAINS. TAPER OFF SCATTERED
STORMS TO ISOLATED SHOWERS MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM EDT THURSDAY...
TUESDAY COULD BE A MIX OF CONVECTION FROM PULSE STORMS IN THE EARLY
AFTERNOON TRANSITIONING TO PREFRONTAL CONVECTION IN THE EARLY
EVENING THROUGH THE EARLY MORNING HOURS. ON WEDNESDAY...A COLD FRONT
WILL SLIDE ACROSS THE REGION WITH THE BEST AREAL COVERAGE OF THE
STRONGER STORMS BEING ACROSS THE PIEDMONT. THE COLD FRONT MAY
WASHOUT OR STALL WITH THE DEW POINT FRONT HANGING BACK ACROSS THE
OHIO VALLEY. UNDER HEATING...SCATTERED CONVECTION MAY FIRE AGAIN
ACROSS THE AREA THURSDAY ESPECIALLY ALONG AND SOUTH OF THE VA/NC
BORDER.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 735 AM EDT FRIDAY...
PATCHES MVFR TO IFR CLOUDS WILL LIFT THIS MORNING WITH ALL TAF
SITES VFR BY 14Z/10AM. ENOUGH HEATING AND DECENT INSTABILITY BY
NOON/16Z FOR SHOWERS AND THUNDERSTORMS TO DEVELOP AS A WARM FRONT
MOVES INTO THE AREA FROM THE OHIO VALLEY.
A STRONGER SHORT WAVE WILL REACH THE FORECAST AREA TONIGHT. HAVE
KEPT CEILINGS VFR AT KROA/KBCB AND KDAN WITH SHOWERS...MAINLY
AFTER 02Z/10PM. MODERATE CONFIDENCE OF MVFR CEILINGS FOR
KLYH/KLWB/KBLF WITH A PROLONGED PERIOD OF SHOWERS AND EMBEDDED
THUNDERSTORMS OVERNIGHT.
EXTENDED AVIATION DISCUSSION...
A WEAK FLOW PATTERN HOLDING OVER THE WEEKEND WILL KEEP THE STORM
CHANCES EACH AFTERNOON THROUGH EARLY EVENING SAT/SUN BUT COVERAGE
FOR NOW LOOKS A BIT LESS EACH DAY BEHIND THE PASSING IMPULSE FROM
FRIDAY NIGHT. DEEPER MOISTURE LOOKS TO RETURN NORTH BY EARLY NEXT
WEEK WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON MONDAY.
AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING...
PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. THE
MOST OPTIMAL FLIGHT CONDITIONS EACH DAY SHOULD BE IN THE MID TO
LATE MORNING AFTER FOG/LOW CLOUDS LIFT AND BURN OFF...AND BEFORE
AFTERNOON CONVECTION REDEVELOPS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...RCS
AVIATION...AMS/PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
421 AM EDT FRI JUN 20 2014
.SYNOPSIS...
A WARM FRONT TRAILED FROM MINNESOTA TO KENTUCKY THIS MORNING.
THIS FRONT WILL LIFT NORTHEAST INTO THE AREA TODAY. LOW PRESSURE
WILL MOVE ALONG THIS FRONT...THROUGH THE OHIO VALLEY TONIGHT...THEN
INTO VIRGINIA ON SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EDT FRIDAY...
WARM FRONT...MAINLY INDICATED AROUND 850 MB...ACROSS THE OHIO VALLEY
WILL BRING SOME WARM AIR ADVECTION AND KEEP DEEPER MOISTURE IN THE
AREA TODAY. AGAIN EXPECTING SCATTERED THUNDERSTORMS THIS AFTERNOON.
SIMILAR TO THURSDAY...HIGH CLOUDS WILL CUT BACK ON HEATING IN THE
MORNING AND THEREFORE THE AMOUNT OF INSTABILITY IN THE AFTERNOON.
STILL ENOUGH CAPE...FORECAST TO BE AROUND 1500 J/KG...FOR A THREAT
OF STRONGER THUNDERSTORMS BEFORE 00Z/8PM. HRRR BRINGS PRECIPITATION
IN TO THE FORECAST AROUND 17Z/1PM.
MODELS HAVE BEEN TRENDED COOLER WITH MAXIMUM TEMPERATURES FOR TODAY.
HIGH WILL DEPEND ON HOW MUCH HIGH CLOUDS FROM THIS MORNING CAN ERODE
BEFORE THUNDERSTORMS DEVELOP.
SHORT WAVE OVER ILLINOIS AND INDIANA WILL MOVE SOUTHEAST...REACHING
WESTERN PARTS OF THE FORECAST AREA JUST AFTER 00Z AND SLOWLY MOVING
ACROSS THE COUNTY WARNING AREA OVERNIGHT. HAVE INCREASED
PROBABILITY OF PRECIPITATION TONIGHT WITH HIGHEST PROBABILITY AFTER
MIDNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS OF 320 AM EDT FRIDAY...
LOW PRESSURE WILL TRACK SOUTHEAST FROM NORTHERN WEST VIRGINIA
SATURDAY MORNING AND REACHES EASTERN VIRGINIA BY SATURDAY AFTERNOON.
THE NAM...GFS AND ECMWF SUPPORT GOOD COVERAGE OF SHOWERS AND
THUNDERSTORMS SATURDAY AS DISTURBANCE TRACKS EASTWARD ALONG THE
THETA-E BOUNDARY. INCREASED POPS FOR SATURDAY ESPECIALLY SATURDAY
MORNING. SPC SWODY2 HAS PLACED THE SLIGHT RISK OF SEVERE
THUNDERSTORMS ACROSS THE CENTRAL PLAINS WITH A SEE TEXT IN EASTERN
CAROLINAS. WITH ADDITIONAL CLOUD COVER AND PRECIPITATION
SATURDAY...LOWERED HIGH TEMPERATURES WITH READINGS FROM THE UPPER
70S IN THE MOUNTAINS TO UPPER 80S IN THE PIEDMONT. AFTER THE
DISTURBANCE EXITS THE AREA SATURDAY EVENING...A SLIGHT COOLER AND
DRY AIRMASS WILL TEMPORARY BUILD OVER THE REGION SATURDAY NIGHT. LOW
TEMPERATURES SATURDAY NIGHT WILL RANGE FROM AROUND 60 DEGREES IN THE
WEST TO THE MID 60S IN THE EAST.
SFC HIGH PRESSURE PROGGED TO BE CENTERED EAST SOUTHEAST OF NEW
ENGLAND ON SUNDAY...AND SLOWLY BUILDS SOUTHWARD. DECREASED POPS FOR
SUNDAY AS A NORTHERLY FLOW AND LESS INSTABILITIES SHOULD LEAD TO
LESS CONVECTION. WITH CAUTION...HELD ON TO SCATTERED AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS. THE GFS WAS MORE ROBUST WITH
CONVECTION COMPARED TO ECMWF AND NAM FOR SUNDAY. WENT WITH HIGH
TEMPERATURES SUNDAY FROM THE UPPER 70S IN THE MOUNTAINS TO THE MID
80S IN THE PIEDMONT. SOUTHEASTERLY FLOW OVERNIGHT SUNDAY MAY KEEP A
FEW SHOWERS ONGOING INTO EARLY MONDAY MORNING. THE BEST CHANCE FOR
SHOWERS SUNDAY NIGHT WILL OCCUR ALONG THE SOUTHERN BLUE RIDGE
MOUNTAINS. LOWS SUNDAY NIGHT WILL GENERALLY BE IN THE 60S.
LEANED TOWARDS HPCGUIDE FOR MONDAY WITH PULSE STORM AND THE PRIMARY
FOCUS FOR CONVECTION ACROSS THE MOUNTAINS. TAPER OFF SCATTERED
STORMS TO ISOLATED SHOWERS MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM EDT THURSDAY...
TUESDAY COULD BE A MIX OF CONVECTION FROM PULSE STORMS IN THE EARLY
AFTERNOON TRANSITIONING TO PREFRONTAL CONVECTION IN THE EARLY
EVENING THROUGH THE EARLY MORNING HOURS. ON WEDNESDAY...A COLD FRONT
WILL SLIDE ACROSS THE REGION WITH THE BEST AREAL COVERAGE OF THE
STRONGER STORMS BEING ACROSS THE PIEDMONT. THE COLD FRONT MAY
WASHOUT OR STALL WITH THE DEW POINT FRONT HANGING BACK ACROSS THE
OHIO VALLEY. UNDER HEATING...SCATTERED CONVECTION MAY FIRE AGAIN
ACROSS THE AREA THURSDAY ESPECIALLY ALONG AND SOUTH OF THE VA/NC
BORDER.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
AS OF 145 AM EDT FRIDAY...
OBSERVATIONS ACROSS THE REGION SHOWED LITTLE TO NO IFR
CLOUDS...EXCEPT FOR KBLF. LOW CONFIDENCE AS TO HOW EXTENSIVE IFR
CLOUDS MAY BE BEFORE 12Z THIS MORNING. BETTER CHANCE OF LOW CLOUDS
MAY BE ALONG A WEAK ZONE OF CONVERGENCE FROM SOUTHERN WEST
VIRGINIA INTO SOUTHEAST VIRGINIA. HIGH CLOUDS OVER THE AREA MAY
ALSO LIMIT FOG DEVELOPMENT EARLY THIS MORNING.
LATEST GUIDANCE INDICATES THAT INSTABILITY MAY BE MUCH LESS INTO
THIS AFTERNOON. CONVECTION LIKELY FAR WEST BUT SHOWERS AND
THUNDERSTORMS MAY NOT REACH EAST OF THE BLUE RIDGE UNTIL LATE IN
THE EAST.
EXTENDED AVIATION DISCUSSION...
A WEAK FLOW PATTERN HOLDING OVER THE WEEKEND WILL KEEP THE STORM
CHANCES EACH AFTERNOON THROUGH EARLY EVENING SAT/SUN BUT COVERAGE
FOR NOW LOOKS A BIT LESS EACH DAY BEHIND THE PASSING IMPULSE FROM
FRIDAY NIGHT. DEEPER MOISTURE LOOKS TO RETURN NORTH BY EARLY NEXT
WEEK WITH BETTER COVERAGE OF AFTERNOON/EVENING STORMS ON MONDAY.
AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING...
PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. THE
MOST OPTIMAL FLIGHT CONDITIONS EACH DAY SHOULD BE IN THE MID TO
LATE MORNING AFTER FOG/LOW CLOUDS LIFT AND BURN OFF...AND BEFORE
AFTERNOON CONVECTION REDEVELOPS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...RCS
AVIATION...AMS/PM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
634 PM CDT SAT JUN 21 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 345 PM CDT SAT JUN 21 2014
AT 3 PM...A MESOSCALE CONVECTIVE VORTICITY...GENERATED FROM THE
THUNDERSTORMS IN NEBRASKA AND SOUTH DAKOTA LAST EVENING...WAS
MOVING EAST THROUGH SOUTHERN WISCONSIN. THIS SYSTEM IS GENERATING
SHOWERS AND A FEW THUNDERSTORMS IN AN AREA OF 2500 J/KG SURFACE
CAPES. BOTH THE 21.12Z ARW AND LATEST HRRR ARE IN GOOD AGREEMENT
THAT A FEW SHOWERS WILL LINGER ACROSS ADAMS AND JUNEAU COUNTIES IN
CENTRAL WISCONSIN THROUGH 22.03Z...AND THEN THE REMAINDER OF
TONIGHT WILL BE DRY AS SUBSIDENCE BUILDS ACROSS THE AREA IN THE
WAKE OF THE CONVECTIVELY INDUCED VORT MAX AND SHORT WAVE RIDGE.
ON SUNDAY...THE 21.12Z MODELS ARE IN GOOD AGREEMENT THAT SCATTERED
SHOWERS AND THUNDERSTORMS WILL DEVELOP DURING THE MORNING ACROSS
SOUTHEAST MINNESOTA AND NORTHEAST IOWA AHEAD OF AN APPROACHING
COLD FRONT AND SHORT WAVE TROUGH MOVING OUT OF THE CENTRAL PLAINS.
THESE SHOWERS AND THUNDERSTORMS THEN BECOME MORE WIDESPREAD ACROSS
THE ENTIRE FORECAST AREA AS THE UPPER LEVEL DIVERGENCE INCREASES...
THE AREA ENTERS THE RIGHT ENTRANCE REGION OF A 50 KNOT 250 MB
JET...AND THE SURFACE BASE CAPES CLIMB INTO THE 3-4K J/KG RANGE.
WHILE THE MODELS ARE IN AGREEMENT WITH THIS...THEY DO DIFFER SOME
ON HOW ORGANIZED THIS CONVECTION BECOMES DURING THE AFTERNOON. THE
ARW SUGGEST A LINE OF STORMS BY EARLY AFTERNOON. MEANWHILE THE
21.12Z SPC WRF SUGGESTS THAT THE CONVECTION WILL BE LESS
ORGANIZED. WHILE THE 0-3 KM AND 0-6 KM SHEAR IS NOT SUFFICIENT FOR
THE DEVELOPMENT OF SUPERCELLS...THE MID LEVEL LAPSE RATES ARE
RUNNING IN THE 7 TO 8 C/KM RANGE WHICH WOULD BE SUFFICIENT FOR THE
DEVELOPMENT OF LARGE HAIL AND DRY AIR BELOW THE CLOUDS MAY AID IN
STRENGTHENING THE DOWN DRAFTS...SO WILL HAVE TO WATCH OUT FOR
PULSE SEVERE STORMS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 PM CDT SAT JUN 21 2014
FROM SUNDAY NIGHT INTO MONDAY...THE CONVECTION BECOMES MORE
ORGANIZED AS THE COLD FRONT AND SURFACE LOW MOVES SLOWLY THROUGH
THE FORECAST AREA. STRONG 850 MB MOISTURE JET WILL RESULT IN THE
DEVELOPMENT OF A MESOSCALE CONVECTIVE COMPLEX. IN ADDITION...
PRECIPITABLE WATER VALUES CLIMB INTO THE 1.7 TO 1.9 INCH RANGE
AND WARM CLOUD DEPTHS CLIMB TO 4 KM AHEAD OF THE SURFACE LOW.
THIS WILL RESULT IN THE THREAT OF HEAVY RAIN AND POTENTIALLY SOME
MORE FLOODING. WITH MODELS DEVIATING ON THE TIMING...LOCATION OF
THE SURFACE LOW...AND STRENGTH OF THE SHORT WAVE TROUGH...HELD OFF
ISSUING A FLOOD WATCH FOR NOW. WHILE THE 0-6 KM SHEAR REMAINS
WEAK...THE 0-3 KM DOES EXCEED 30 KNOTS AND THIS COULD RESULT IN
SOME WIND DAMAGE AS THE SYSTEM EVOLVES.
MONDAY NIGHT IS NOW LOOKING DRY IN ALL OF THE DETERMINISTIC MODELS
AS SUBSIDENCE DEVELOPS IN THE WAKE OF THE DEPARTING LOW PRESSURE
SYSTEM. AS A RESULT...EITHER REDUCED OR TOOK OUT THE
PRECIPITATION CHANCES ACROSS THE ENTIRE FORECAST AREA.
FROM TUESDAY THROUGH THURSDAY....A CANADIAN COLD FRONT DROPS INTO
THE REGION. WHILE THE MODELS HAVE BEEN CONSISTENT AT DOING THIS...
THEY CONTINUE TO STRUGGLE ON HOW FAR SOUTH THIS FRONT WILL GET.
THE MODELS ALSO CONTINUE TO SHOW THAT SEVERAL SHORT WAVE TROUGHS
WILL MOVE ALONG THIS BOUNDARY. HOWEVER THERE IS ONLY WEAK MOISTURE
TRANSPORT INTO THE REGION WHICH RESULTS IN WEAK 0-3 KM AND 0-6 KM
SHEAR...THUS NOT EXPECTING ANY SEVERE WEATHER AT THIS TIME.
FROM THURSDAY NIGHT INTO SATURDAY...A PATTERN SHIFT OCCURS AS A
LONG WAVE TROUGH MOVES INTO THE WESTERN UNITED STATES. WHILE BOTH
THE GFS AND ECMWF ARE IN AGREEMENT THAT AND UPPER LEVEL RIDGE WILL
BUILD AHEAD OF THIS TROUGH...THERE CONTINUES TO BE QUESTIONS ON
HOW FAR WEST THIS RIDGE WILL END UP AND THIS WILL GREATLY AFFECT
WHETHER WE WILL SEE PRECIPITATION OR NOT. DUE TO THIS...JUTS
STAYED WITH THE MODEL CONSENSUS FOR NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 633 PM CDT SAT JUN 21 2014
LIGHT/VARIABLE WINDS THIS EVENING WILL BECOME SOUTHERLY OVERNIGHT
IN ADVANCE OF AN APPROACHING SHORTWAVE TROUGH SUNDAY. MOSTLY CLEAR
SKIES TONIGHT UNTIL ANVIL CIRRUS FROM NORTHERN PLAINS SPREADS
OVERHEAD. NOT EXPECTING FOG AT EITHER KRST/KLSE DESPITE FAVORABLE
LOW LEVEL WINDS AND T/TD SPREAD. FOR SUNDAY...FOCUS IS ON
THUNDERSTORM POTENTIAL WHICH IS EXPECTED TO BE MAINLY FROM 21Z
THROUGH SUNDAY EVENING. THE HIGHER CHANCES FOR AVIATION IMPACTS
LOOK TO BE AFTER 00Z.
&&
.HYDROLOGY...
ISSUED AT 345 PM CDT SAT JUN 21 2014
THE MISSISSIPPI TRIBUTARIES HAVE CRESTED AND ARE NOW FALLING.
MEANWHILE THE MISSISSIPPI RIVER IS RISING WITH FLOODING EXPECTED
AT WABASHA...WINONA...AND MCGREGOR. AT THIS TIME...LA CROSSE IS
NOT EXPECTED TO REACH FLOOD STAGE. HOWEVER THIS COULD CHANGE
DEPENDING ON HOW MUCH RAIN FALLS ON SUNDAY NIGHT.
BETWEEN 1 AND 3 INCHES OF RAIN LOOKS POSSIBLE ON SUNDAY
NIGHT...BUT DUE TO MODEL INCONSISTENCIES HELD OFF ISSUING A FLOOD
WATCH FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...ZT
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
344 PM CDT FRI JUN 20 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 344 PM CDT FRI JUN 20 2014
AT 3 PM...TWO BOUNDARIES WERE LOCATED ACROSS THE FORECAST AREA.
THE FIRST OF THESE TWO EXTENDS FROM NEW RICHMOND /KRNH/ TO
LA CROSSE WISCONSIN. BOTH THE RAP AND LAPS DATA SHOW 150 TO
200 J/KG OF SURFACE TO 3 KM CAPE...STRONG LAYER ENHANCED
STRETCHING POTENTIAL...STEEP 0-2 KM LAPSE RATES /GREATER THAN
9 C/KM /...AND WEAK TO MODERATE SURFACE RELATIVE VORTICITY. THIS
WOULD BE SUPPORTIVE OF NON-SUPERCELL TORNADOES. THESE CONDITIONS
CONTINUE THROUGH 21.02Z. HOWEVER AT THIS TIME...IT LOOKS LIKE THE
CONVERGENCE WILL NOT BE GREAT ENOUGH FOR THEIR DEVELOPMENT.
A SECOND BOUNDARY LOOKS TO BE EITHER A DRY LINE OR A DIFFERENTIAL
HEATING BOUNDARY ACROSS CENTRAL WISCONSIN. THERE WAS A BRIEF
SHOWER AT WAUSAU. JUST LIKE THE PREVIOUS BOUNDARY...THE
CONVERGENCE IS NOT THAT STRONG ALONG THE BOUNDARY. WITH 2 TO 3K
SURFACE BASED CAPES...WILL HAVE TO MONITOR THIS AREA FOR
DEVELOPMENT.
FURTHER NORTHWEST...A SHORT WAVE TROUGH WAS MOVING ACROSS NORTHERN
MINNESOTA. THIS SYSTEM WAS MOVING THROUGH AN AREA OF 1K SURFACE
CAPES. THIS HAS RESULTED IN THE DEVELOPMENT OF SHOWERS AND STORMS.
WITH THE RAP SHOWING EFFECTIVE SHEAR GREATER THAN 40 KNOTS...AREAS
NORTH OF INTERSTATE 94 WILL HAVE TO BE MONITORED FOR THE POTENTIAL
OF SEVERE WEATHER. THERE IS A BOUNDARY NORTH OF PHILLIPS
WISCONSIN. THIS COULD AID IN THE DEVELOPMENT OF A FEW TORNADOES.
MEANWHILE FURTHER SOUTH...THE THREATS WILL BE LARGE HAIL AND
DAMAGING WINDS. THIS MAY AFFECT CLARK AND TAYLOR COUNTIES LATE
THIS AFTERNOON AND EVENING...BUT THIS IS HIGHLY DEPENDENT ON
WHETHER STORMS CAN EVEN DEVELOP. MANY OF THE MESO MODELS SUGGEST
THAT THIS WILL NOT BE THE CASE.
FINALLY...AN AREA OF SHOWERS AND STORMS ARE DEVELOPING AHEAD OF A
SHORT WAVE TROUGH MOVING OUT OF CENTRAL NEBRASKA. A FEW OF THESE
STORMS HAVE ALREADY BECOME SEVERE. THE GFS...ECMWF...AND ARW
SUGGEST THAT THESE SUPERCELLS WILL DEVELOP INTO A MESOSCALE
CONVECTIVE COMPLEX WHICH WILL MOVE THROUGH OUR AREAS ALONG AND
SOUTH OF INTERSTATE 90 BETWEEN 21.06Z AND 21.15Z. AT THIS
TIME...IT LOOKS LIKE THE 0-3 KM AND 0-6 KM SHEAR WILL BE TOO WEAK
FOR ANY SEVERE WEATHER WITH THIS COMPLEX. ONE THING THAT WILL HAVE
TO WATCHED IS THAT THE HOP WRF AND HRRR SUGGEST THAT THIS COMPLEX
MAY DIVE SOUTHEAST TOWARD THE BETTER INSTABILITY ACROSS
MISSOURI...SO WILL HAVE TO WATCH THIS CLOSELY LATE TONIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 344 PM CDT FRI JUN 20 2014
THIS PART OF THE FORECAST IS GREATLY COMPLICATED DUE TO ZONAL FLOW
ALOFT. THE EXTENDED MODELS ARE SHOWING VARYING TIMES AND
STRENGTHS OF SHORT WAVES EMBEDDED IN THIS FLOW. OVERALL...THE BEST
CHANCE OF SHOWERS AND THUNDERSTORMS LOOKS TO BE FROM SUNDAY NIGHT
THROUGH MONDAY AS A SHORT WAVE TROUGH MOVES THROUGH THE CENTRAL
PLAINS AND MID MISSISSIPPI RIVER VALLEY...AND FROM TUESDAY THROUGH
WEDNESDAY AS A CANADIAN COLD FRONT DROPS INTO THE AREA. THIS FRONT
WILL LIKELY INCREASE THE SHEAR ACROSS THE AREA FOR THE POTENTIAL
OF SEVERE WEATHER. HOWEVER THERE ARE UNCERTAINTIES ON HOW FAR
SOUTH THIS FRONT WILL GET DUE TO THE ZONAL FLOW. AS A
RESULT...STAYED CLOSE TO THE MODEL CONSENSUS FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1241 PM CDT FRI JUN 20 2014
AS SKIES CLEAR EARLY THIS AFTERNOON...A 3-4KFT CU DECK WILL FORM
BUT SHOULD STAY FEW-SCT. WINDS WILL GENERALLY BE OUT OF THE WEST
AND REMAIN LIGHT AT 10KT OR LESS. THE MAIN QUESTION IS WITH
WHETHER ANY RAIN WILL BE ABLE TO DEVELOP AND TRACK THROUGH
OVERNIGHT. HAVE GONE THE OPTIMISTIC ROUTE AND LEFT CONDITIONS DRY
OVERNIGHT...BUT WILL HAVE TO WATCH THE LATEST TRENDS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1241 PM CDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 1058 AM CDT FRI JUN 20 2014
ADDED A SLIGHT CHANCE FOR SHOWERS/STORMS ACROSS NORTH CENTRAL
WISCONSIN FOR THIS AFTERNOON. THE PAST FEW RUNS OF THE HRRR HAVE
INITIATED SOME WEAK CONVECTION IN EASTERN TO NORTH CENTRAL
WISCONSIN ALONG A BOUNDARY THAT CURRENTLY RESIDES IN THAT AREA.
20.13Z RAP SOUNDINGS FROM NECEDAH SHOWS THAT THE ATMOSPHERE
REMAINS CAPPED OFF...BUT ITS SURFACE DEW POINT MAY BE A TAD DRY
COMPARED TO WHAT THE HRRR HAS. REGARDLESS...SAW ENOUGH TO WARRANT
SOME SMALL CHANCES FOR SHOWERS/STORMS IN THIS AREA.
OTHERWISE...THE CLOUD SHIELD WILL CLEAR FROM THE WEST TODAY AND
PROVIDE A FAIRLY WARM DAY WITH TEMPERATURES CLIMBED UP INTO THE
80S.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES TONIGHT THROUGH
SUNDAY.
LOCAL AND REGIONAL RADARS THIS MORNING SHOWING MOST OF THE SHOWERS
THIS MORNING WERE OVER THE NORTHERN AND EASTERN SECTIONS OF
WISCONSIN WITH JUST SOME WIDELY SCATTERED ACTIVITY OVER THE
CENTRAL PART OF THE STATE. THESE SHOWERS WERE MOVING OFF TO THE
NORTH/NORTHEAST AND THE 20.05Z HRRR SUGGESTS THESE SHOULD MOVE OUT
OF THE FORECAST AREA BY 12Z. WILL MONITOR THE RADAR TRENDS BUT MAY
HAVE TO START THE MORNING WITH A VERY SMALL RAIN CHANCE ACROSS THE
FAR NORTHERN AND EASTERN PARTS OF THE FORECAST AREA WITH ANY
REMAINING SHOWERS EXPECTED TO BE COMPLETELY OUT OF THE AREA BY MID
MORNING.
THE UPPER LEVEL LOW OVER SASKATCHEWAN WILL LIFT SLOWLY NORTHEAST
THROUGH TONIGHT AND BECOME AN OPEN WAVE OVER SOUTHERN MANITOBA AND
WESTERN ONTARIO ALLOWING THE FLOW OVER THE UPPER MIDWEST TO BECOME
ZONAL. ONE SHORT WAVE TROUGH ROUNDING THE REMAINS OF THIS UPPER
LEVEL LOW IS EXPECTED TO MOVE ACROSS NORTHERN MINNESOTA TONIGHT
WITH ANOTHER WEAKER WAVE COMING OUT OF THE ROCKIES AND ACROSS
NEBRASKA AND SOUTHERN IOWA. NOT A LOT OF PV ADVECTION WITH EITHER
OF THESE WAVES...BUT ENOUGH WARM AIR ADVECTION SHOULD OCCUR TO
PRODUCE 4 TO 6 UBAR/S OF UP GLIDE ON THE 305K ISENTROPIC SURFACE.
THE MODELS ARE SPLIT ON HOW MUCH AND WHERE THE MOISTURE TRANSPORT
WILL BE WITH THESE WAVES. THE 20.00Z NAM SUGGESTS WEAK TRANSPORT
SHOULD OCCUR AHEAD OF THE NORTHERN WAVE INTO NORTHERN WISCONSIN
AND MINNESOTA WHILE THE 20.00Z GFS AND ECMWF HAVE THE MOISTURE
TRANSPORT AHEAD OF THE SOUTHERN WAVE INTO NEBRASKA WHERE THEY
DEVELOP A CONVECTIVE COMPLEX. THE GFS THEN KEEPS THIS COMPLEX
GENERALLY SOUTH OF THE AREA WHILE THE ECMWF BRINGS INTO THE THE
AREA. THE 20.03Z SREF PROBABILITIES TEND TO FAVOR THE GFS SOLUTION
WITH THE CONVECTIVE COMPLEX BUT ALSO HAVE SOME LOW PROBABILITIES
ACROSS THE NORTH SIMILAR TO THE NAM. WITH SUCH WEAK FORCING
SIGNALS AND DIFFERING MODEL SOLUTIONS...WILL JUST HAVE SOME LOW
RAIN CHANCES ACROSS MOST THE AREA FOR THE OVERNIGHT HOURS.
THE ZONAL FLOW CONTINUES INTO SATURDAY WITH ALL THE MODELS SHOWING
ANOTHER WEAK WAVE COMING ACROSS THE NORTHERN ROCKIES INTO THE
UPPER MIDWEST. THE GFS IS THE FARTHEST NORTH BRINGING THIS ACROSS
MINNESOTA INTO IOWA WHILE THE NAM AND ECMWF TAKE IT ACROSS IOWA.
THIS RESULTS IN BIG DIFFERENCES IN HOW MUCH AND WHERE THE RAIN
COULD FALL. THE NAM AND ECMWF KEEP THE MAJORITY OF THE RAIN TO THE
SOUTH OF THE AREA WHILE THE GFS WOULD INDICATE ALL OF THE FORECAST
AREA WOULD HAVE A CHANCE FOR GETTING WET. AGAIN...THE SREF
PROBABILITIES FAVOR THE NAM AND ECMWF SOLUTIONS SO PLAN TO SHOW 20
TO 30 PERCENT CHANCES THROUGH THE DAY WITH THESE HIGHEST ACROSS
THE SOUTH. THE RAIN THAT DEVELOPS SATURDAY SHOULD CONTINUE ACROSS
THE SOUTH INTO SATURDAY EVENING BEFORE STARTING TO MOVE OFF TO THE
EAST SATURDAY NIGHT.
A STRONGER SHORT WAVE TROUGH IS EXPECTED TO MOVE OUT OF THE
ROCKIES AND START TO APPROACH THE AREA SUNDAY. THE PV ADVECTION IN
THE 500-300 MB LAYER WILL STAY TO THE WEST OF THE AREA. THE
ISENTROPIC UP GLIDE AHEAD OF THIS WAVE SHOULD MOVE INTO THE
WESTERN SECTIONS OF IOWA AND MINNESOTA BY LATE IN THE DAY SUNDAY.
IF THE MODELS REMAIN CONSISTENT WITH THESE SIGNALS...THE BEST RAIN
CHANCES SHOULD BE CONFINED TO THE WESTERN SECTIONS OF THE FORECAST
AREA AND THE EASTERN SECTIONS COULD BE DRY...BUT WITH THE GFS
BEING QUICKER TO MOVE THIS SYSTEM IN...WILL SHOW A 30 TO 40
PERCENT CHANCE FROM EAST TO WEST.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MODEL DIFFERENCE CONTINUE INTO EARLY NEXT WEEK AS WELL.
GENERAL CONSENSUS THAT THE SHORT WAVE TROUGH THAT COMES OUT SUNDAY
WILL WEAKEN AS IT MOVES TOWARD MINNESOTA IN FAVOR OF ANOTHER WAVE
COMING ACROSS NEBRASKA OR KANSAS. THE ECMWF THEN TAKES THIS WAVE
NORTHEAST AND INTO THE GREAT LAKES REGION THROUGH MONDAY WHILE THE
GFS AMPLIFIES THIS FORMING AN UPPER LEVEL LOW OVER THE UPPER
MIDWEST MONDAY NIGHT WITH THE 20.00Z GEM DOING SOMETHING VERY
SIMILAR. BOTH THE ECMWF AND GFS THEN SHOW WEAK RIDGING BUILDING
OVER THE UPPER MIDWEST BY THE END OF PERIOD WITH THE ECMWF QUICKER
TO DO THIS THAN THE GFS. BECAUSE OF THE DIFFERENCES BETWEEN THE
MODELS...WILL HAVE SOME RAIN CHANCES THROUGH THE ENTIRE PERIOD
WITH THE HIGHEST CHANCES MONDAY INTO MONDAY NIGHT WHEN THE FORCING
FROM THE WAVE SHOULD BE THE STRONGEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1241 PM CDT FRI JUN 20 2014
AS SKIES CLEAR EARLY THIS AFTERNOON...A 3-4KFT CU DECK WILL FORM
BUT SHOULD STAY FEW-SCT. WINDS WILL GENERALLY BE OUT OF THE WEST
AND REMAIN LIGHT AT 10KT OR LESS. THE MAIN QUESTION IS WITH
WHETHER ANY RAIN WILL BE ABLE TO DEVELOP AND TRACK THROUGH
OVERNIGHT. HAVE GONE THE OPTIMISTIC ROUTE AND LEFT CONDITIONS DRY
OVERNIGHT...BUT WILL HAVE TO WATCH THE LATEST TRENDS.
&&
.HYDROLOGY...
ISSUED AT 342 AM CDT FRI JUN 20 2014
WITH ALL THE RECENT RAINS...NUMEROUS RIVERS AND STREAMS HAVE
FLOODING ALONG THEM RESULTING IN AREAL AND RIVER FLOOD WARNINGS.
WITH A DRY DAY TODAY...SOME OF THE WATER MAY RECEDE ENOUGH TO
ALLOW THE AREAL FLOOD WARNINGS TO BE DISCONTINUED OR MADE SMALLER
IN SIZE. HOWEVER...MANY OF THE RIVERS WILL REMAIN ABOVE FLOOD
STAGE INTO THE WEEKEND. WHILE ADDITIONAL RAINFALL IS IN THE
FORECAST THROUGH THE WEEKEND...EXPECTED AMOUNTS AT THIS TIME
SHOULD NOT BE ENOUGH TO AGGRAVATE EXISTING FLOODING PROBLEMS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1058 AM CDT FRI JUN 20 2014
.UPDATE...
ISSUED AT 1058 AM CDT FRI JUN 20 2014
ADDED A SLIGHT CHANCE FOR SHOWERS/STORMS ACROSS NORTH CENTRAL
WISCONSIN FOR THIS AFTERNOON. THE PAST FEW RUNS OF THE HRRR HAVE
INITIATED SOME WEAK CONVECTION IN EASTERN TO NORTH CENTRAL
WISCONSIN ALONG A BOUNDARY THAT CURRENTLY RESIDES IN THAT AREA.
20.13Z RAP SOUNDINGS FROM NECEDAH SHOWS THAT THE ATMOSPHERE
REMAINS CAPPED OFF...BUT ITS SURFACE DEW POINT MAY BE A TAD DRY
COMPARED TO WHAT THE HRRR HAS. REGARDLESS...SAW ENOUGH TO WARRANT
SOME SMALL CHANCES FOR SHOWERS/STORMS IN THIS AREA.
OTHERWISE...THE CLOUD SHIELD WILL CLEAR FROM THE WEST TODAY AND
PROVIDE A FAIRLY WARM DAY WITH TEMPERATURES CLIMBED UP INTO THE
80S.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES TONIGHT THROUGH
SUNDAY.
LOCAL AND REGIONAL RADARS THIS MORNING SHOWING MOST OF THE SHOWERS
THIS MORNING WERE OVER THE NORTHERN AND EASTERN SECTIONS OF
WISCONSIN WITH JUST SOME WIDELY SCATTERED ACTIVITY OVER THE
CENTRAL PART OF THE STATE. THESE SHOWERS WERE MOVING OFF TO THE
NORTH/NORTHEAST AND THE 20.05Z HRRR SUGGESTS THESE SHOULD MOVE OUT
OF THE FORECAST AREA BY 12Z. WILL MONITOR THE RADAR TRENDS BUT MAY
HAVE TO START THE MORNING WITH A VERY SMALL RAIN CHANCE ACROSS THE
FAR NORTHERN AND EASTERN PARTS OF THE FORECAST AREA WITH ANY
REMAINING SHOWERS EXPECTED TO BE COMPLETELY OUT OF THE AREA BY MID
MORNING.
THE UPPER LEVEL LOW OVER SASKATCHEWAN WILL LIFT SLOWLY NORTHEAST
THROUGH TONIGHT AND BECOME AN OPEN WAVE OVER SOUTHERN MANITOBA AND
WESTERN ONTARIO ALLOWING THE FLOW OVER THE UPPER MIDWEST TO BECOME
ZONAL. ONE SHORT WAVE TROUGH ROUNDING THE REMAINS OF THIS UPPER
LEVEL LOW IS EXPECTED TO MOVE ACROSS NORTHERN MINNESOTA TONIGHT
WITH ANOTHER WEAKER WAVE COMING OUT OF THE ROCKIES AND ACROSS
NEBRASKA AND SOUTHERN IOWA. NOT A LOT OF PV ADVECTION WITH EITHER
OF THESE WAVES...BUT ENOUGH WARM AIR ADVECTION SHOULD OCCUR TO
PRODUCE 4 TO 6 UBAR/S OF UP GLIDE ON THE 305K ISENTROPIC SURFACE.
THE MODELS ARE SPLIT ON HOW MUCH AND WHERE THE MOISTURE TRANSPORT
WILL BE WITH THESE WAVES. THE 20.00Z NAM SUGGESTS WEAK TRANSPORT
SHOULD OCCUR AHEAD OF THE NORTHERN WAVE INTO NORTHERN WISCONSIN
AND MINNESOTA WHILE THE 20.00Z GFS AND ECMWF HAVE THE MOISTURE
TRANSPORT AHEAD OF THE SOUTHERN WAVE INTO NEBRASKA WHERE THEY
DEVELOP A CONVECTIVE COMPLEX. THE GFS THEN KEEPS THIS COMPLEX
GENERALLY SOUTH OF THE AREA WHILE THE ECMWF BRINGS INTO THE THE
AREA. THE 20.03Z SREF PROBABILITIES TEND TO FAVOR THE GFS SOLUTION
WITH THE CONVECTIVE COMPLEX BUT ALSO HAVE SOME LOW PROBABILITIES
ACROSS THE NORTH SIMILAR TO THE NAM. WITH SUCH WEAK FORCING
SIGNALS AND DIFFERING MODEL SOLUTIONS...WILL JUST HAVE SOME LOW
RAIN CHANCES ACROSS MOST THE AREA FOR THE OVERNIGHT HOURS.
THE ZONAL FLOW CONTINUES INTO SATURDAY WITH ALL THE MODELS SHOWING
ANOTHER WEAK WAVE COMING ACROSS THE NORTHERN ROCKIES INTO THE
UPPER MIDWEST. THE GFS IS THE FARTHEST NORTH BRINGING THIS ACROSS
MINNESOTA INTO IOWA WHILE THE NAM AND ECMWF TAKE IT ACROSS IOWA.
THIS RESULTS IN BIG DIFFERENCES IN HOW MUCH AND WHERE THE RAIN
COULD FALL. THE NAM AND ECMWF KEEP THE MAJORITY OF THE RAIN TO THE
SOUTH OF THE AREA WHILE THE GFS WOULD INDICATE ALL OF THE FORECAST
AREA WOULD HAVE A CHANCE FOR GETTING WET. AGAIN...THE SREF
PROBABILITIES FAVOR THE NAM AND ECMWF SOLUTIONS SO PLAN TO SHOW 20
TO 30 PERCENT CHANCES THROUGH THE DAY WITH THESE HIGHEST ACROSS
THE SOUTH. THE RAIN THAT DEVELOPS SATURDAY SHOULD CONTINUE ACROSS
THE SOUTH INTO SATURDAY EVENING BEFORE STARTING TO MOVE OFF TO THE
EAST SATURDAY NIGHT.
A STRONGER SHORT WAVE TROUGH IS EXPECTED TO MOVE OUT OF THE
ROCKIES AND START TO APPROACH THE AREA SUNDAY. THE PV ADVECTION IN
THE 500-300 MB LAYER WILL STAY TO THE WEST OF THE AREA. THE
ISENTROPIC UP GLIDE AHEAD OF THIS WAVE SHOULD MOVE INTO THE
WESTERN SECTIONS OF IOWA AND MINNESOTA BY LATE IN THE DAY SUNDAY.
IF THE MODELS REMAIN CONSISTENT WITH THESE SIGNALS...THE BEST RAIN
CHANCES SHOULD BE CONFINED TO THE WESTERN SECTIONS OF THE FORECAST
AREA AND THE EASTERN SECTIONS COULD BE DRY...BUT WITH THE GFS
BEING QUICKER TO MOVE THIS SYSTEM IN...WILL SHOW A 30 TO 40
PERCENT CHANCE FROM EAST TO WEST.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MODEL DIFFERENCE CONTINUE INTO EARLY NEXT WEEK AS WELL.
GENERAL CONSENSUS THAT THE SHORT WAVE TROUGH THAT COMES OUT SUNDAY
WILL WEAKEN AS IT MOVES TOWARD MINNESOTA IN FAVOR OF ANOTHER WAVE
COMING ACROSS NEBRASKA OR KANSAS. THE ECMWF THEN TAKES THIS WAVE
NORTHEAST AND INTO THE GREAT LAKES REGION THROUGH MONDAY WHILE THE
GFS AMPLIFIES THIS FORMING AN UPPER LEVEL LOW OVER THE UPPER
MIDWEST MONDAY NIGHT WITH THE 20.00Z GEM DOING SOMETHING VERY
SIMILAR. BOTH THE ECMWF AND GFS THEN SHOW WEAK RIDGING BUILDING
OVER THE UPPER MIDWEST BY THE END OF PERIOD WITH THE ECMWF QUICKER
TO DO THIS THAN THE GFS. BECAUSE OF THE DIFFERENCES BETWEEN THE
MODELS...WILL HAVE SOME RAIN CHANCES THROUGH THE ENTIRE PERIOD
WITH THE HIGHEST CHANCES MONDAY INTO MONDAY NIGHT WHEN THE FORCING
FROM THE WAVE SHOULD BE THE STRONGEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 656 AM CDT FRI JUN 20 2014
AREAS OF FOG AND STRATUS WILL PRODUCE LIFR CONDITIONS AT KRST
THROUGH 13Z. MVFR CONDITIONS ARE EXPECTED AT KLSE THROUGH 13Z.
HIGH PRESSURE WILL THEN BUILD INTO THE REGION TODAY WITH VFR
CONDITIONS EXPECTED. LOOKING AT THE FORECAST SOUNDINGS...THINKING
SCATTERED TO BROKEN CUMULUS WILL DEVELOP LATE THIS MORNING BUT
THEN SHOULD GRADUALLY FLATTEN AND DISSIPATE DURING THE AFTERNOON
HOURS AS DRIER AIR MOVES IN. A WEAK SYSTEM THEN APPROACHES FROM
THE PLAINS TONIGHT WITH INCREASING CLOUDS EXPECTED.
&&
.HYDROLOGY...
ISSUED AT 342 AM CDT FRI JUN 20 2014
WITH ALL THE RECENT RAINS...NUMEROUS RIVERS AND STREAMS HAVE
FLOODING ALONG THEM RESULTING IN AREAL AND RIVER FLOOD WARNINGS.
WITH A DRY DAY TODAY...SOME OF THE WATER MAY RECEDE ENOUGH TO
ALLOW THE AREAL FLOOD WARNINGS TO BE DISCONTINUED OR MADE SMALLER
IN SIZE. HOWEVER...MANY OF THE RIVERS WILL REMAIN ABOVE FLOOD
STAGE INTO THE WEEKEND. WHILE ADDITIONAL RAINFALL IS IN THE
FORECAST THROUGH THE WEEKEND...EXPECTED AMOUNTS AT THIS TIME
SHOULD NOT BE ENOUGH TO AGGRAVATE EXISTING FLOODING PROBLEMS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...04
LONG TERM...04
AVIATION...WETENKAMP
HYDROLOGY...04
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1011 AM CDT FRI JUN 20 2014
.UPDATE...
AREA OF RAIN IS CURRENTLY EXITING THE NORTHEAST FORECAST
AREA...WITH DRY WEATHER EXPECTED FOR THE REMAINDER OF THE DAY
AFTER THIS RAIN MOVES OUT. THERE COULD BE SOME LATE MORNING AND
AFTERNOON BREAKS IN THE CLOUDS...BUT OTHERWISE EXPECT MOSTLY
CLOUDY CONDITIONS FOR MUCH OF THE DAY. OCCASIONAL FOG NEAR LAKE
MICHIGAN SHOULD ALSO IMPROVE THROUGH THE DAY. HIGH TEMPERATURES IN
THE EAST MAY NEED TO BE LOWERED A BIT WITH ONSHORE WINDS LIKELY
PERSISTING INTO THE AFTERNOON.
&&
.AVIATION/18Z TAFS/...
CIGS ARE SHOWING SOME SIGNS OF IMPROVEMENT IN THE WEST...BUT
LATEST MODEL SOUNDINGS SHOW CIGS MAY NOT GET ABOVE MVFR THROUGH
THE AFTERNOON. WILL HAVE TO CONTINUE TO EVALUATE UPSTREAM CIGS
AND LATEST MODEL DATA FOR THIS EVENING AND OVERNIGHT...AS THERE
ARE MIXED SIGNALS WITH CLOUD COVER TONIGHT. THE NAM IS SUGGESTING
SOME LOW STRATUS POSSIBLE...WHILE THE GFS BRINGS VFR CONDITIONS
THROUGH THE NIGHT.
OCCASIONAL FOG NEAR LAKE MICHIGAN SHOULD IMPROVE THROUGH THE DAY
TODAY.
AFTER THE AREA OF RAIN IN THE NORTHEAST MOVES OUT LATE THIS
MORNING...COULD SEE A FEW SHOWERS TONIGHT INTO SATURDAY
MORNING...WITH A CHANCE FOR SHOWERS AND STORMS IN THE AFTERNOON.
OTHER THAN SOME LOWER CIGS/VSBYS WITHIN AREAS OF
SHOWERS/STORMS...LOOKS LIKE MAINLY VFR CONDITIONS FOR SATURDAY.
&&
.PREV DISCUSSION... /ISSUED 447 AM CDT FRI JUN 20 2014/
TODAY...FORECAST CONFIDENCE IS MEDIUM.
CURRENT BAND OF LIGHT SHOWERS BEING DRIVEN BY IMPULSE ROTATING
AROUND EASTERN FLANK OF CLOSED 500 MB LOW WATER VAPOR IMAGERY
SHOWS MOVING EAST ALONG THE U.S./CANADIAN BORDER OVER NORTHEAST
MONTANA/SASKATCHEWAN. THE IMPULSE...AND THE WEAK SURFACE
REFLECTION OF THIS IMPULSE...CROSS SRN WI THIS MORNING REACHING
THE FAR SE CORNER OF WI/NE IL BY 18Z. CURRENT TIMING PUSHES PCPN
EAST OF STATE BY 15Z AT THE LATEST...BUT SOME CONCERN ABOUT LOW
LEVEL CONVERGENCE/FRONTOGENETIC RESPONSE IN THE EAST BEHIND LOW.
MODEL SOUNDINGS SHOW THE COLUMN DRYING BEHIND THIS IMPULSE...NO
DOUBT AIDED BY SUBSIDENCE ASSOCIATED WITH UPPER LEVEL CONVERGENCE
IN RIGHT EXIT REGION OF UPPER JETLET ON SRN EDGE OF THE CLOSED
UPPER LOW THAT SPREADS ACROSS SRN WI LATE THIS MORNING/AFTERNOON.
HOWEVER CONCERN ABOUT THE INCREASING CAPE VALUES AND STEEP LOW-
LEVEL LAPSE RATES WITH DAYTIME HEATING. WILL NOT HAVE POPS IN THE
EAST PAST 20Z BUT LATEST HRRR DOES SHOW SOME SCATTERED PCPN IN
CONVERGENCE FARTHER INLAND.
TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
MOST OF THE NIGHT IS QUIET...BUT NEAR ZONAL FLOW BRINGS A WEAK
SHORT WAVE TOWARD THE REGION BY 12Z SATURDAY. WILL LIMIT SLIGHT
CHANCE POPS TO THE FAR NORTHWEST WITH LOW EXPECTATION OF ANYTHING
MEASURABLE AS LIMITED MOISTURE AVAILABLE MAINLY IN THE MID LEVELS.
SHORT TERM...SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
SHORT TERM MODELS GENERALLY SHOWING A MESOSCALE CONVECTIVE SYSTEM
SHIFTING FROM NORTHERN IOWA TO SOUTHEAST IOWA AND NORTHERN
ILLINOIS SATURDAY AND SATURDAY NIGHT. SOME VARIATION IN THE TRACK
OF THIS FEATURE. MODELS ALSO TRYING TO GENERATE QPF WITHIN WEAK
WARM AIR ADVECTION REGIME AND MOIST/UNSTABLE AIRMASS. WEAK LOW
LEVEL FRONTOGENESIS RESPONSE ALSO SEEN IN THE AREA.
NAM/GFS DIFFER ON MEAN LAYER CAPES...BUT ADJUSTING
TEMPERATURE/DEW POINTS IN LOWEST 100 MB MEAN LAYER SUGGESTS 1000
TO 1500 J/KG AT LEAST. NAM CAPPED WITH GFS MOSTLY UNCAPPED
SATURDAY...WITH NAM LOSING INSTABILITY SATURDAY NIGHT. DEEP LAYER
SHEAR IS MODEST SATURDAY ON NAM...WEAK ON GFS. BOTH ARE WEAK WITH
SHEAR SATURDAY NIGHT.
FOR NOW...CONTINUED POPS FOR THIS PERIOD. NO ALL DAY RAINFALL IS
EXPECTED AT THIS TIME. WARM AND HUMID CONDITIONS WILL CONTINUE
AWAY FROM LAKE MICHIGAN.
MODELS DIFFER MORE WITH SUNDAY AND SUNDAY NIGHT...AS
NAM/ECMWF/CANADIAN MODELS ARE FAIRLY DRY WITH INFLUENCE OF HIGH
PRESSURE TO THE NORTHEAST OF THE REGION. GFS CONTINUES TO HAVE
WEAK WARM AIR ADVECTION AND QPF WITHIN MOIST/UNSTABLE
AIRMASS...WITH NAM SHOWING MORE ELEVATED CAPE PROFILES.
FOR NOW...WILL CONTINUE CHANCE POPS FOR THIS PERIOD. MAY HAVE TO
RAMP DOWN POPS IN LATER FORECASTS IF DRIER LOOK CONTINUES ON
NAM/ECMWF/CANADIAN MODELS. WARM AND HUMID AGAIN AWAY FROM THE LAKE
ON SUNDAY.
LONG TERM...MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS
MEDIUM.
ECMWF/GFS BRING LOW PRESSURE NORTHEAST THROUGH THE REGION MONDAY
INTO EARLY TUESDAY...ALONG WITH A COLD FRONT AND 500 MB SHORTWAVE
TROUGH. THIS SHOULD RESULT IN DECENT CHANCES FOR SHOWERS AND
THUNDERSTORMS. CONTINUED HIGHER END POPS FOR MONDAY AND MONDAY
NIGHT...SLIGHTLY LOWER ON TUESDAY. WARM AND HUMID CONDITIONS
SHOULD CONTINUE.
A BIT MORE UNCERTAINTY FURTHER OUT IN THE FORECAST...SO WILL USE
CONSENSUS POPS AND TEMPERATURES FOR THIS PERIOD. IT APPEARS THAT A
COOLER AND LESS HUMID AIRMASS MAY MOVE INTO THE REGION AFTER THE
COLD FRONTAL PASSAGE TUESDAY...AND PERHAPS A DRY PERIOD WITH HIGH
PRESSURE. SOME QPF OCCURS FROM TIME TO TIME...SO NOT SOLD ON A DRY
FORECAST JUST YET.
AVIATION/12Z TAFS/...PER WESTERN OBSERVATIONS LIFR CIGS EXPECTED
TO LIFT TO MVFR AFTER PASSAGE OF LAST POCKET OF SHOWERS CROSSES
REGION EARLY THIS MORNING.
VSBYS ARE ANOTHER QUESTION AS A BREAK IN THE LOWER CIGS HAS
ALLOWED ENOUGH COOLING FOR 1/2 TO 1/4 MILE VSBYS AT KUGN AND KENW.
DENSE FOG HAS FORMED WHERE SKIES CLEARED IN IOWA. WILL WATCH
CLOSELY BUT EXPECT PREVAILING VSBYS TO HOLD BETWEEN 1 AND 2
MILES...THEN IMPROVE AFTER DAYBREAK AND PASSAGE OF THE LAST OF
THE RAIN SHOWERS.
WILL KEEP CIGS AT MVFR LEVELS UNTIL EARLY AFTERNOON THEN VFR
CONDITIONS WHEN DRIER AIR MOVES IN BEHIND WEAK SURFACE LOW. LIGHT
WINDS AND MOIST CONDITIONS BRING A GOOD POTENTIAL OF FOG TONIGHT.
SREF PROBABILITIES FOR LESS THAN 3 MILE VSBYS JUMP UP AFTER
06Z...WITH LESS THAN 1 MILE CHANCES FOCUSED NEAR KBUU AND KENW.
WILL HOLD VSBYS AT MVFR LEVELS EXCEPT AT KENW WITH IFR BETWEEN 09Z
AND 12Z.
MARINE...CURRENT WEB CAMS NOT SHOWING FOG ALONG THE IMMEDIATE
SHORE BUT APPEARS TO BE SOME OFFSHORE FOG. WILL KEEP MENTION OF
AREAS OF FOG THROUGH THE DAY UNTIL NORTHEAST WINDS LATER THIS
AFTERNOON SCOUR OUT HIGHER DEW POINT AIR OVER THE LAKE. POTENTIAL
FOR FOG RETURNS WITH HIGHER DEW POINTS SATURDAY AHEAD OF NEXT WEAK
SYSTEM.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...REM
SATURDAY THROUGH THURSDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
656 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES TONIGHT THROUGH
SUNDAY.
LOCAL AND REGIONAL RADARS THIS MORNING SHOWING MOST OF THE SHOWERS
THIS MORNING WERE OVER THE NORTHERN AND EASTERN SECTIONS OF
WISCONSIN WITH JUST SOME WIDELY SCATTERED ACTIVITY OVER THE
CENTRAL PART OF THE STATE. THESE SHOWERS WERE MOVING OFF TO THE
NORTH/NORTHEAST AND THE 20.05Z HRRR SUGGESTS THESE SHOULD MOVE OUT
OF THE FORECAST AREA BY 12Z. WILL MONITOR THE RADAR TRENDS BUT MAY
HAVE TO START THE MORNING WITH A VERY SMALL RAIN CHANCE ACROSS THE
FAR NORTHERN AND EASTERN PARTS OF THE FORECAST AREA WITH ANY
REMAINING SHOWERS EXPECTED TO BE COMPLETELY OUT OF THE AREA BY MID
MORNING.
THE UPPER LEVEL LOW OVER SASKATCHEWAN WILL LIFT SLOWLY NORTHEAST
THROUGH TONIGHT AND BECOME AN OPEN WAVE OVER SOUTHERN MANITOBA AND
WESTERN ONTARIO ALLOWING THE FLOW OVER THE UPPER MIDWEST TO BECOME
ZONAL. ONE SHORT WAVE TROUGH ROUNDING THE REMAINS OF THIS UPPER
LEVEL LOW IS EXPECTED TO MOVE ACROSS NORTHERN MINNESOTA TONIGHT
WITH ANOTHER WEAKER WAVE COMING OUT OF THE ROCKIES AND ACROSS
NEBRASKA AND SOUTHERN IOWA. NOT A LOT OF PV ADVECTION WITH EITHER
OF THESE WAVES...BUT ENOUGH WARM AIR ADVECTION SHOULD OCCUR TO
PRODUCE 4 TO 6 UBAR/S OF UP GLIDE ON THE 305K ISENTROPIC SURFACE.
THE MODELS ARE SPLIT ON HOW MUCH AND WHERE THE MOISTURE TRANSPORT
WILL BE WITH THESE WAVES. THE 20.00Z NAM SUGGESTS WEAK TRANSPORT
SHOULD OCCUR AHEAD OF THE NORTHERN WAVE INTO NORTHERN WISCONSIN
AND MINNESOTA WHILE THE 20.00Z GFS AND ECMWF HAVE THE MOISTURE
TRANSPORT AHEAD OF THE SOUTHERN WAVE INTO NEBRASKA WHERE THEY
DEVELOP A CONVECTIVE COMPLEX. THE GFS THEN KEEPS THIS COMPLEX
GENERALLY SOUTH OF THE AREA WHILE THE ECMWF BRINGS INTO THE THE
AREA. THE 20.03Z SREF PROBABILITIES TEND TO FAVOR THE GFS SOLUTION
WITH THE CONVECTIVE COMPLEX BUT ALSO HAVE SOME LOW PROBABILITIES
ACROSS THE NORTH SIMILAR TO THE NAM. WITH SUCH WEAK FORCING
SIGNALS AND DIFFERING MODEL SOLUTIONS...WILL JUST HAVE SOME LOW
RAIN CHANCES ACROSS MOST THE AREA FOR THE OVERNIGHT HOURS.
THE ZONAL FLOW CONTINUES INTO SATURDAY WITH ALL THE MODELS SHOWING
ANOTHER WEAK WAVE COMING ACROSS THE NORTHERN ROCKIES INTO THE
UPPER MIDWEST. THE GFS IS THE FARTHEST NORTH BRINGING THIS ACROSS
MINNESOTA INTO IOWA WHILE THE NAM AND ECMWF TAKE IT ACROSS IOWA.
THIS RESULTS IN BIG DIFFERENCES IN HOW MUCH AND WHERE THE RAIN
COULD FALL. THE NAM AND ECMWF KEEP THE MAJORITY OF THE RAIN TO THE
SOUTH OF THE AREA WHILE THE GFS WOULD INDICATE ALL OF THE FORECAST
AREA WOULD HAVE A CHANCE FOR GETTING WET. AGAIN...THE SREF
PROBABILITIES FAVOR THE NAM AND ECMWF SOLUTIONS SO PLAN TO SHOW 20
TO 30 PERCENT CHANCES THROUGH THE DAY WITH THESE HIGHEST ACROSS
THE SOUTH. THE RAIN THAT DEVELOPS SATURDAY SHOULD CONTINUE ACROSS
THE SOUTH INTO SATURDAY EVENING BEFORE STARTING TO MOVE OFF TO THE
EAST SATURDAY NIGHT.
A STRONGER SHORT WAVE TROUGH IS EXPECTED TO MOVE OUT OF THE
ROCKIES AND START TO APPROACH THE AREA SUNDAY. THE PV ADVECTION IN
THE 500-300 MB LAYER WILL STAY TO THE WEST OF THE AREA. THE
ISENTROPIC UP GLIDE AHEAD OF THIS WAVE SHOULD MOVE INTO THE
WESTERN SECTIONS OF IOWA AND MINNESOTA BY LATE IN THE DAY SUNDAY.
IF THE MODELS REMAIN CONSISTENT WITH THESE SIGNALS...THE BEST RAIN
CHANCES SHOULD BE CONFINED TO THE WESTERN SECTIONS OF THE FORECAST
AREA AND THE EASTERN SECTIONS COULD BE DRY...BUT WITH THE GFS
BEING QUICKER TO MOVE THIS SYSTEM IN...WILL SHOW A 30 TO 40
PERCENT CHANCE FROM EAST TO WEST.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MODEL DIFFERENCE CONTINUE INTO EARLY NEXT WEEK AS WELL.
GENERAL CONSENSUS THAT THE SHORT WAVE TROUGH THAT COMES OUT SUNDAY
WILL WEAKEN AS IT MOVES TOWARD MINNESOTA IN FAVOR OF ANOTHER WAVE
COMING ACROSS NEBRASKA OR KANSAS. THE ECMWF THEN TAKES THIS WAVE
NORTHEAST AND INTO THE GREAT LAKES REGION THROUGH MONDAY WHILE THE
GFS AMPLIFIES THIS FORMING AN UPPER LEVEL LOW OVER THE UPPER
MIDWEST MONDAY NIGHT WITH THE 20.00Z GEM DOING SOMETHING VERY
SIMILAR. BOTH THE ECMWF AND GFS THEN SHOW WEAK RIDGING BUILDING
OVER THE UPPER MIDWEST BY THE END OF PERIOD WITH THE ECMWF QUICKER
TO DO THIS THAN THE GFS. BECAUSE OF THE DIFFERENCES BETWEEN THE
MODELS...WILL HAVE SOME RAIN CHANCES THROUGH THE ENTIRE PERIOD
WITH THE HIGHEST CHANCES MONDAY INTO MONDAY NIGHT WHEN THE FORCING
FROM THE WAVE SHOULD BE THE STRONGEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 656 AM CDT FRI JUN 20 2014
AREAS OF FOG AND STRATUS WILL PRODUCE LIFR CONDITIONS AT KRST
THROUGH 13Z. MVFR CONDITIONS ARE EXPECTED AT KLSE THROUGH 13Z.
HIGH PRESSURE WILL THEN BUILD INTO THE REGION TODAY WITH VFR
CONDITIONS EXPECTED. LOOKING AT THE FORECAST SOUNDINGS...THINKING
SCATTERED TO BROKEN CUMULUS WILL DEVELOP LATE THIS MORNING BUT
THEN SHOULD GRADUALLY FLATTEN AND DISSIPATE DURING THE AFTERNOON
HOURS AS DRIER AIR MOVES IN. A WEAK SYSTEM THEN APPROACHES FROM
THE PLAINS TONIGHT WITH INCREASING CLOUDS EXPECTED.
&&
.HYDROLOGY...
ISSUED AT 342 AM CDT FRI JUN 20 2014
WITH ALL THE RECENT RAINS...NUMEROUS RIVERS AND STREAMS HAVE
FLOODING ALONG THEM RESULTING IN AREAL AND RIVER FLOOD WARNINGS.
WITH A DRY DAY TODAY...SOME OF THE WATER MAY RECEDE ENOUGH TO
ALLOW THE AREAL FLOOD WARNINGS TO BE DISCONTINUED OR MADE SMALLER
IN SIZE. HOWEVER...MANY OF THE RIVERS WILL REMAIN ABOVE FLOOD
STAGE INTO THE WEEKEND. WHILE ADDITIONAL RAINFALL IS IN THE
FORECAST THROUGH THE WEEKEND...EXPECTED AMOUNTS AT THIS TIME
SHOULD NOT BE ENOUGH TO AGGRAVATE EXISTING FLOODING PROBLEMS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...WETENKAMP
HYDROLOGY...04
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
447 AM CDT FRI JUN 20 2014
.TODAY...FORECAST CONFIDENCE IS MEDIUM.
CURRENT BAND OF LIGHT SHOWERS BEING DRIVEN BY IMPULSE ROTATING
AROUND EASTERN FLANK OF CLOSED 500 MB LOW WATER VAPOR IMAGERY
SHOWS MOVING EAST ALONG THE U.S./CANADIAN BORDER OVER NORTHEAST
MONTANA/SASKATCHEWAN. THE IMPULSE...AND THE WEAK SURFACE
REFLECTION OF THIS IMPULSE...CROSS SRN WI THIS MORNING REACHING
THE FAR SE CORNER OF WI/NE IL BY 18Z. CURRENT TIMING PUSHES PCPN
EAST OF STATE BY 15Z AT THE LATEST...BUT SOME CONCERN ABOUT LOW
LEVEL CONVERGENCE/FRONTOGENETIC RESPONSE IN THE EAST BEHIND LOW.
MODEL SOUNDINGS SHOW THE COLUMN DRYING BEHIND THIS IMPULSE...NO
DOUBT AIDED BY SUBSIDENCE ASSOCIATED WITH UPPER LEVEL CONVERGENCE
IN RIGHT EXIT REGION OF UPPER JETLET ON SRN EDGE OF THE CLOSED
UPPER LOW THAT SPREADS ACROSS SRN WI LATE THIS MORNING/AFTERNOON.
HOWEVER CONCERN ABOUT THE INCREASING CAPE VALUES AND STEEP LOW-
LEVEL LAPSE RATES WITH DAYTIME HEATING. WILL NOT HAVE POPS IN THE
EAST PAST 20Z BUT LATEST HRRR DOES SHOW SOME SCATTERED PCPN IN
CONVERGENCE FARTHER INLAND.
.TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
MOST OF THE NIGHT IS QUIET...BUT NEAR ZONAL FLOW BRINGS A WEAK
SHORT WAVE TOWARD THE REGION BY 12Z SATURDAY. WILL LIMIT SLIGHT
CHANCE POPS TO THE FAR NORTHWEST WITH LOW EXPECTATION OF ANYTHING
MEASURABLE AS LIMITED MOISTURE AVAILABLE MAINLY IN THE MID LEVELS.
.SHORT TERM...SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
SHORT TERM MODELS GENERALLY SHOWING A MESOSCALE CONVECTIVE SYSTEM
SHIFTING FROM NORTHERN IOWA TO SOUTHEAST IOWA AND NORTHERN
ILLINOIS SATURDAY AND SATURDAY NIGHT. SOME VARIATION IN THE TRACK
OF THIS FEATURE. MODELS ALSO TRYING TO GENERATE QPF WITHIN WEAK
WARM AIR ADVECTION REGIME AND MOIST/UNSTABLE AIRMASS. WEAK LOW
LEVEL FRONTOGENESIS RESPONSE ALSO SEEN IN THE AREA.
NAM/GFS DIFFER ON MEAN LAYER CAPES...BUT ADJUSTING
TEMPERATURE/DEW POINTS IN LOWEST 100 MB MEAN LAYER SUGGESTS 1000
TO 1500 J/KG AT LEAST. NAM CAPPED WITH GFS MOSTLY UNCAPPED
SATURDAY...WITH NAM LOSING INSTABILITY SATURDAY NIGHT. DEEP LAYER
SHEAR IS MODEST SATURDAY ON NAM...WEAK ON GFS. BOTH ARE WEAK WITH
SHEAR SATURDAY NIGHT.
FOR NOW...CONTINUED POPS FOR THIS PERIOD. NO ALL DAY RAINFALL IS
EXPECTED AT THIS TIME. WARM AND HUMID CONDITIONS WILL CONTINUE
AWAY FROM LAKE MICHIGAN.
MODELS DIFFER MORE WITH SUNDAY AND SUNDAY NIGHT...AS
NAM/ECMWF/CANADIAN MODELS ARE FAIRLY DRY WITH INFLUENCE OF HIGH
PRESSURE TO THE NORTHEAST OF THE REGION. GFS CONTINUES TO HAVE
WEAK WARM AIR ADVECTION AND QPF WITHIN MOIST/UNSTABLE
AIRMASS...WITH NAM SHOWING MORE ELEVATED CAPE PROFILES.
FOR NOW...WILL CONTINUE CHANCE POPS FOR THIS PERIOD. MAY HAVE TO
RAMP DOWN POPS IN LATER FORECASTS IF DRIER LOOK CONTINUES ON
NAM/ECMWF/CANADIAN MODELS. WARM AND HUMID AGAIN AWAY FROM THE LAKE
ON SUNDAY.
.LONG TERM...MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS
MEDIUM.
ECMWF/GFS BRING LOW PRESSURE NORTHEAST THROUGH THE REGION MONDAY
INTO EARLY TUESDAY...ALONG WITH A COLD FRONT AND 500 MB SHORTWAVE
TROUGH. THIS SHOULD RESULT IN DECENT CHANCES FOR SHOWERS AND
THUNDERSTORMS. CONTINUED HIGHER END POPS FOR MONDAY AND MONDAY
NIGHT...SLIGHTLY LOWER ON TUESDAY. WARM AND HUMID CONDITIONS
SHOULD CONTINUE.
A BIT MORE UNCERTAINTY FURTHER OUT IN THE FORECAST...SO WILL USE
CONSENSUS POPS AND TEMPERATURES FOR THIS PERIOD. IT APPEARS THAT A
COOLER AND LESS HUMID AIRMASS MAY MOVE INTO THE REGION AFTER THE
COLD FRONTAL PASSAGE TUESDAY...AND PERHAPS A DRY PERIOD WITH HIGH
PRESSURE. SOME QPF OCCURS FROM TIME TO TIME...SO NOT SOLD ON A DRY
FORECAST JUST YET.
.AVIATION/12Z TAFS/...PER WESTERN OBSERVATIONS LIFR CIGS EXPECTED
TO LIFT TO MVFR AFTER PASSAGE OF LAST POCKET OF SHOWERS CROSSES
REGION EARLY THIS MORNING.
VSBYS ARE ANOTHER QUESTION AS A BREAK IN THE LOWER CIGS HAS
ALLOWED ENOUGH COOLING FOR 1/2 TO 1/4 MILE VSBYS AT KUGN AND KENW.
DENSE FOG HAS FORMED WHERE SKIES CLEARED IN IOWA. WILL WATCH
CLOSELY BUT EXPECT PREVAILING VSBYS TO HOLD BETWEEN 1 AND 2
MILES...THEN IMPROVE AFTER DAYBREAK AND PASSAGE OF THE LAST OF
THE RAIN SHOWERS.
WILL KEEP CIGS AT MVFR LEVELS UNTIL EARLY AFTERNOON THEN VFR
CONDITIONS WHEN DRIER AIR MOVES IN BEHIND WEAK SURFACE LOW. LIGHT
WINDS AND MOIST CONDITIONS BRING A GOOD POTENTIAL OF FOG TONIGHT.
SREF PROBABILITIES FOR LESS THAN 3 MILE VSBYS JUMP UP AFTER
06Z...WITH LESS THAN 1 MILE CHANCES FOCUSED NEAR KBUU AND KENW.
WILL HOLD VSBYS AT MVFR LEVELS EXCEPT AT KENW WITH IFR BETWEEN 09Z
AND 12Z.
.MARINE...CURRENT WEB CAMS NOT SHOWING FOG ALONG THE IMMEDIATE
SHORE BUT APPEARS TO BE SOME OFFSHORE FOG. WILL KEEP MENTION OF
AREAS OF FOG THROUGH THE DAY UNTIL NORTHEAST WINDS LATER THIS
AFTERNOON SCOUR OUT HIGHER DEW POINT AIR OVER THE LAKE. POTENTIAL
FOR FOG RETURNS WITH HIGHER DEW POINTS SATURDAY AHEAD OF NEXT WEAK
SYSTEM.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
SATURDAY THROUGH THURSDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
342 AM CDT FRI JUN 20 2014
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES TONIGHT THROUGH
SUNDAY.
LOCAL AND REGIONAL RADARS THIS MORNING SHOWING MOST OF THE SHOWERS
THIS MORNING WERE OVER THE NORTHERN AND EASTERN SECTIONS OF
WISCONSIN WITH JUST SOME WIDELY SCATTERED ACTIVITY OVER THE
CENTRAL PART OF THE STATE. THESE SHOWERS WERE MOVING OFF TO THE
NORTH/NORTHEAST AND THE 20.05Z HRRR SUGGESTS THESE SHOULD MOVE OUT
OF THE FORECAST AREA BY 12Z. WILL MONITOR THE RADAR TRENDS BUT MAY
HAVE TO START THE MORNING WITH A VERY SMALL RAIN CHANCE ACROSS THE
FAR NORTHERN AND EASTERN PARTS OF THE FORECAST AREA WITH ANY
REMAINING SHOWERS EXPECTED TO BE COMPLETELY OUT OF THE AREA BY MID
MORNING.
THE UPPER LEVEL LOW OVER SASKATCHEWAN WILL LIFT SLOWLY NORTHEAST
THROUGH TONIGHT AND BECOME AN OPEN WAVE OVER SOUTHERN MANITOBA AND
WESTERN ONTARIO ALLOWING THE FLOW OVER THE UPPER MIDWEST TO BECOME
ZONAL. ONE SHORT WAVE TROUGH ROUNDING THE REMAINS OF THIS UPPER
LEVEL LOW IS EXPECTED TO MOVE ACROSS NORTHERN MINNESOTA TONIGHT
WITH ANOTHER WEAKER WAVE COMING OUT OF THE ROCKIES AND ACROSS
NEBRASKA AND SOUTHERN IOWA. NOT A LOT OF PV ADVECTION WITH EITHER
OF THESE WAVES...BUT ENOUGH WARM AIR ADVECTION SHOULD OCCUR TO
PRODUCE 4 TO 6 UBAR/S OF UP GLIDE ON THE 305K ISENTROPIC SURFACE.
THE MODELS ARE SPLIT ON HOW MUCH AND WHERE THE MOISTURE TRANSPORT
WILL BE WITH THESE WAVES. THE 20.00Z NAM SUGGESTS WEAK TRANSPORT
SHOULD OCCUR AHEAD OF THE NORTHERN WAVE INTO NORTHERN WISCONSIN
AND MINNESOTA WHILE THE 20.00Z GFS AND ECMWF HAVE THE MOISTURE
TRANSPORT AHEAD OF THE SOUTHERN WAVE INTO NEBRASKA WHERE THEY
DEVELOP A CONVECTIVE COMPLEX. THE GFS THEN KEEPS THIS COMPLEX
GENERALLY SOUTH OF THE AREA WHILE THE ECMWF BRINGS INTO THE THE
AREA. THE 20.03Z SREF PROBABILITIES TEND TO FAVOR THE GFS SOLUTION
WITH THE CONVECTIVE COMPLEX BUT ALSO HAVE SOME LOW PROBABILITIES
ACROSS THE NORTH SIMILAR TO THE NAM. WITH SUCH WEAK FORCING
SIGNALS AND DIFFERING MODEL SOLUTIONS...WILL JUST HAVE SOME LOW
RAIN CHANCES ACROSS MOST THE AREA FOR THE OVERNIGHT HOURS.
THE ZONAL FLOW CONTINUES INTO SATURDAY WITH ALL THE MODELS SHOWING
ANOTHER WEAK WAVE COMING ACROSS THE NORTHERN ROCKIES INTO THE
UPPER MIDWEST. THE GFS IS THE FARTHEST NORTH BRINGING THIS ACROSS
MINNESOTA INTO IOWA WHILE THE NAM AND ECMWF TAKE IT ACROSS IOWA.
THIS RESULTS IN BIG DIFFERENCES IN HOW MUCH AND WHERE THE RAIN
COULD FALL. THE NAM AND ECMWF KEEP THE MAJORITY OF THE RAIN TO THE
SOUTH OF THE AREA WHILE THE GFS WOULD INDICATE ALL OF THE FORECAST
AREA WOULD HAVE A CHANCE FOR GETTING WET. AGAIN...THE SREF
PROBABILITIES FAVOR THE NAM AND ECMWF SOLUTIONS SO PLAN TO SHOW 20
TO 30 PERCENT CHANCES THROUGH THE DAY WITH THESE HIGHEST ACROSS
THE SOUTH. THE RAIN THAT DEVELOPS SATURDAY SHOULD CONTINUE ACROSS
THE SOUTH INTO SATURDAY EVENING BEFORE STARTING TO MOVE OFF TO THE
EAST SATURDAY NIGHT.
A STRONGER SHORT WAVE TROUGH IS EXPECTED TO MOVE OUT OF THE
ROCKIES AND START TO APPROACH THE AREA SUNDAY. THE PV ADVECTION IN
THE 500-300 MB LAYER WILL STAY TO THE WEST OF THE AREA. THE
ISENTROPIC UP GLIDE AHEAD OF THIS WAVE SHOULD MOVE INTO THE
WESTERN SECTIONS OF IOWA AND MINNESOTA BY LATE IN THE DAY SUNDAY.
IF THE MODELS REMAIN CONSISTENT WITH THESE SIGNALS...THE BEST RAIN
CHANCES SHOULD BE CONFINED TO THE WESTERN SECTIONS OF THE FORECAST
AREA AND THE EASTERN SECTIONS COULD BE DRY...BUT WITH THE GFS
BEING QUICKER TO MOVE THIS SYSTEM IN...WILL SHOW A 30 TO 40
PERCENT CHANCE FROM EAST TO WEST.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 AM CDT FRI JUN 20 2014
THE MODEL DIFFERENCE CONTINUE INTO EARLY NEXT WEEK AS WELL.
GENERAL CONSENSUS THAT THE SHORT WAVE TROUGH THAT COMES OUT SUNDAY
WILL WEAKEN AS IT MOVES TOWARD MINNESOTA IN FAVOR OF ANOTHER WAVE
COMING ACROSS NEBRASKA OR KANSAS. THE ECMWF THEN TAKES THIS WAVE
NORTHEAST AND INTO THE GREAT LAKES REGION THROUGH MONDAY WHILE THE
GFS AMPLIFIES THIS FORMING AN UPPER LEVEL LOW OVER THE UPPER
MIDWEST MONDAY NIGHT WITH THE 20.00Z GEM DOING SOMETHING VERY
SIMILAR. BOTH THE ECMWF AND GFS THEN SHOW WEAK RIDGING BUILDING
OVER THE UPPER MIDWEST BY THE END OF PERIOD WITH THE ECMWF QUICKER
TO DO THIS THAN THE GFS. BECAUSE OF THE DIFFERENCES BETWEEN THE
MODELS...WILL HAVE SOME RAIN CHANCES THROUGH THE ENTIRE PERIOD
WITH THE HIGHEST CHANCES MONDAY INTO MONDAY NIGHT WHEN THE FORCING
FROM THE WAVE SHOULD BE THE STRONGEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1212 AM CDT FRI JUN 20 2014
IN THE WAKE OF THE EARLIER CONVECTION...IFR CLOUDS HAVE DEVELOPED
ACROSS THE AREA. THE LONE EXCEPTION IS KRST. THINKING WITH THE
LIGHT WINDS AND CLEARING SKIES THAT THE IFR CONDITIONS WILL SPREAD
INTO THAT TAF SITE TOO. AS DRY AIR MOVES INTO THE REGION ON
FRIDAY MORNING...SKIES WILL CLEAR AND REMAIN THAT WAY THROUGH
FRIDAY EVENING.
&&
.HYDROLOGY...
ISSUED AT 342 AM CDT FRI JUN 20 2014
WITH ALL THE RECENT RAINS...NUMEROUS RIVERS AND STREAMS HAVE
FLOODING ALONG THEM RESULTING IN AREAL AND RIVER FLOOD WARNINGS.
WITH A DRY DAY TODAY...SOME OF THE WATER MAY RECEDE ENOUGH TO
ALLOW THE AREAL FLOOD WARNINGS TO BE DISCONTINUED OR MADE SMALLER
IN SIZE. HOWEVER...MANY OF THE RIVERS WILL REMAIN ABOVE FLOOD
STAGE INTO THE WEEKEND. WHILE ADDITIONAL RAINFALL IS IN THE
FORECAST THROUGH THE WEEKEND...EXPECTED AMOUNTS AT THIS TIME
SHOULD NOT BE ENOUGH TO AGGRAVATE EXISTING FLOODING PROBLEMS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
338 AM CDT FRI JUN 20 2014
.TODAY...FORECAST CONFIDENCE IS MEDIUM.
CURRENT BAND OF LIGHT SHOWERS BEING DRIVEN BY IMPULSE ROTATING
AROUND EASTERN FLANK OF CLOSED 500 MB LOW WATER VAPOR IMAGERY
SHOWS MOVING EAST ALONG THE U.S./CANADIAN BORDER OVER NORTHEAST
MONTANA/SASKATCHEWAN. THE IMPULSE...AND THE WEAK SURFACE
REFLECTION OF THIS IMPULSE...CROSS SRN WI THIS MORNING REACHING
THE FAR SE CORNER OF WI/NE IL BY 18Z. CURRENT TIMING PUSHES PCPN
EAST OF STATE BY 15Z AT THE LATEST...BUT SOME CONCERN ABOUT LOW
LEVEL CONVERGENCE/FRONTOGENETIC RESPONSE IN THE EAST BEHIND LOW.
MODEL SOUNDINGS SHOW THE COLUMN DRYING BEHIND THIS IMPULSE...NO
DOUBT AIDED BY SUBSIDENCE ASSOCIATED WITH UPPER LEVEL CONVERGENCE
IN RIGHT EXIT REGION OF UPPER JETLET ON SRN EDGE OF THE CLOSED
UPPER LOW THAT SPREADS ACROSS SRN WI LATE THIS MORNING/AFTERNOON.
HOWEVER CONCERN ABOUT THE INCREASING CAPE VALUES AND STEEP LOW-
LEVEL LAPSE RATES WITH DAYTIME HEATING. WILL NOT HAVE POPS IN THE
EAST PAST 20Z BUT LATEST HRRR DOES SHOW SOME SCATTERED PCPN IN
CONVERGENCE FARTHER INLAND.
.TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
MOST OF THE NIGHT IS QUIET...BUT NEAR ZONAL FLOW BRINGS A WEAK
SHORT WAVE TOWARD THE REGION BY 12Z SATURDAY. WILL LIMIT SLIGHT
CHANCE POPS TO THE FAR NORTHWEST WITH LOW EXPECTATION OF ANYTHING
MEASURABLE AS LIMITED MOISTURE AVAILABLE MAINLY IN THE MID LEVELS.
.SHORT TERM...SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
SHORT TERM MODELS GENERALLY SHOWING A MESOSCALE CONVECTIVE SYSTEM
SHIFTING FROM NORTHERN IOWA TO SOUTHEAST IOWA AND NORTHERN
ILLINOIS SATURDAY AND SATURDAY NIGHT. SOME VARIATION IN THE TRACK
OF THIS FEATURE. MODELS ALSO TRYING TO GENERATE QPF WITHIN WEAK
WARM AIR ADVECTION REGIME AND MOIST/UNSTABLE AIRMASS. WEAK LOW
LEVEL FRONTOGENESIS RESPONSE ALSO SEEN IN THE AREA.
NAM/GFS DIFFER ON MEAN LAYER CAPES...BUT ADJUSTING
TEMPERATURE/DEW POINTS IN LOWEST 100 MB MEAN LAYER SUGGESTS 1000
TO 1500 J/KG AT LEAST. NAM CAPPED WITH GFS MOSTLY UNCAPPED
SATURDAY...WITH NAM LOSING INSTABILITY SATURDAY NIGHT. DEEP LAYER
SHEAR IS MODEST SATURDAY ON NAM...WEAK ON GFS. BOTH ARE WEAK WITH
SHEAR SATURDAY NIGHT.
FOR NOW...CONTINUED POPS FOR THIS PERIOD. NO ALL DAY RAINFALL IS
EXPECTED AT THIS TIME. WARM AND HUMID CONDITIONS WILL CONTINUE
AWAY FROM LAKE MICHIGAN.
MODELS DIFFER MORE WITH SUNDAY AND SUNDAY NIGHT...AS
NAM/ECMWF/CANADIAN MODELS ARE FAIRLY DRY WITH INFLUENCE OF HIGH
PRESSURE TO THE NORTHEAST OF THE REGION. GFS CONTINUES TO HAVE
WEAK WARM AIR ADVECTION AND QPF WITHIN MOIST/UNSTABLE
AIRMASS...WITH NAM SHOWING MORE ELEVATED CAPE PROFILES.
FOR NOW...WILL CONTINUE CHANCE POPS FOR THIS PERIOD. MAY HAVE TO
RAMP DOWN POPS IN LATER FORECASTS IF DRIER LOOK CONTINUES ON
NAM/ECMWF/CANADIAN MODELS. WARM AND HUMID AGAIN AWAY FROM THE LAKE
ON SUNDAY.
.LONG TERM...MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS
MEDIUM.
ECMWF/GFS BRING LOW PRESSURE NORTHEAST THROUGH THE REGION MONDAY
INTO EARLY TUESDAY...ALONG WITH A COLD FRONT AND 500 MB SHORTWAVE
TROUGH. THIS SHOULD RESULT IN DECENT CHANCES FOR SHOWERS AND
THUNDERSTORMS. CONTINUED HIGHER END POPS FOR MONDAY AND MONDAY
NIGHT...SLIGHTLY LOWER ON TUESDAY. WARM AND HUMID CONDITIONS
SHOULD CONTINUE.
A BIT MORE UNCERTAINTY FURTHER OUT IN THE FORECAST...SO WILL USE
CONSENSUS POPS AND TEMPERATURES FOR THIS PERIOD. IT APPEARS THAT A
COOLER AND LESS HUMID AIRMASS MAY MOVE INTO THE REGION AFTER THE
COLD FRONTAL PASSAGE TUESDAY...AND PERHAPS A DRY PERIOD WITH HIGH
PRESSURE. SOME QPF OCCURS FROM TIME TO TIME...SO NOT SOLD ON A DRY
FORECAST JUST YET.
&&
.AVIATION/12Z TAFS/...COMING SOON.
&&
.MARINE...COMING SOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
SATURDAY THROUGH THURSDAY...WOOD
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
517 PM MDT SAT JUN 21 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 307 PM MDT SAT JUN 21 2014
STORMS HAVE DEVELOPED EARLY THIS AFTN OVER GOSHEN COUNTY AND HAVE
MOVED INTO THE CENTRAL AND NORTHERN PANHANDLE. THEY HAVE STRUGGLED
TO BECOME DISCRETE SO FAR DUE TO THE MARGINAL DEEP LAYER SHEAR
(25-30 KTS) AND HAVE FORMED INTO LINES/CLUSTERS. SPC MESOANALYSIS
SHOWS GOOD INSTABILITY WITH MLCAPES OF 1500-2000 J/KG OVER THE
PANHANDLE. BELIEVE THAT THE MAIN SVR THREAT DURING THE AFTN WILL
BE DAMAGING WINDS WITH THE HIGH LCLS AND DEEP BOUNDARY LAYER OVER
THE PANHANDLE. LARGE HAIL IS LESS OF THE THREAT WITH THE MARGINAL
DEEP LAYER SHEAR...HOWEVER MARGINALLY SVR HAIL WILL BE POSSIBLE. A
SEVERE THUNDERSTORM WATCH WAS ISSUED FOR ALL OF THE NEBRASKA
PANHANDLE THROUGH 03Z. ALL OF THIS STORM ACTIVITY IS OCCURING
AHEAD OF A SHORTWAVE THAT IS CURRENTLY LOCATED OVER WESTERN
COLORADO. THE HRRR MODEL SHOWS MOST STORMS PUSHING EAST OUT OF THE
CWA BY AROUND 00Z.
COLD FRONT BEHIND THE SHORTWAVE WILL PUSH ACROSS THE PLAINS LATE
TONIGHT AND SUNDAY MORNING. WINDS ARE STILL NORTHERLY AT 18Z SUN
AND THEN BECOME MORE NORTHEASTERLY DURING THE AFTN. MODELS HAVE
DECREASED INSTABILITY A BIT OVER YESTERDAYS RUN WITH LI VALUES OF
AROUND -3C IN LARAMIE/PLATTE COUNTIES AND EXTENDING EASTWARD ALONG
THE COLORADO BORDER. STORMS SHOULD DEVELOP BY AFTN IN THE
CONVERGENCE ALONG THE SOUTHERN LARAMIE RANGE...HOWEVER DO NOT
BELIEVE THEY WILL BECOME SVR AS THEY PUSH EASTWARD. STORM COVERAGE
WILL BE MORE LIMITED OVER THE PANHANDLE AS THE AIRMASS IS MORE
STABLE POST FRONTAL. TEMPS WILL BE 10-15 DEGREES COOLER ON SUNDAY.
FOR MONDAY SFC WINDS BECOME MORE SOUTHEASTERLY AND AIRMASS IS MORE
UNSTABLE THAN SUNDAY IN AREAS NEAR THE COLORADO BORDER. THIS IS
THE DAY AFTER THE FROPA...WHICH OFTEN TIMES LEADS TO A GREATER SVR
THREAT. NORTHWESTERLY FLOW ALOFT IS STRONG ENOUGH...COMBINED WITH
THE SOUTHEAST LLVL FLOW...TO PRODUCE 40-45 KTS OF DEEP LAYER SHEAR
SO THERE WILL LIKELY BE SOME SVR POTENTIAL ON MONDAY IN AREAS
ALONG INTERSTATE 80.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 307 PM MDT SAT JUN 21 2014
THE ACTIVE PATTERN WILL CONTINUE INTO NEXT WEEK AS ZONAL FLOW
BECOMES MORE SOUTHWESTERLY BY THE END OF THE WEEK. BOTH THE GFS
AND EURO SOLUTIONS CONTINUE TO ADVERTISE DAILY CHANCES OF
AFTERNOON AND EVENING CONVECTION AS SOUTHEASTERLY LLVL RETURN FLOW
PERSISTS ALL WEEK. THIS WILL RESULT IN PERSISTENT THETA-E RIDGING
OVER MUCH OF THE CWFA THROUGH THE ENTIRE WEEK. TUESDAY WILL BE THE
SECOND DAY POST-FRONTAL...WHICH WHEN COMBINED WITH 0-6KM SHEAR OF
40-50 KNOTS SHOULD SET THE STAGE FOR AN ACTIVE SEVERE WEATHER DAY.
THE GREATEST THREAT WILL BE EAST OF THE LARAMIE RANGE. PROGD
SBCAPES WILL FLARE TO BETWEEN 2000-3000 J/KG FOR WED AND
THU...WHICH SHOULD BE MORE THAN ENOUGH TO COMPENSATE FOR SOMEWHAT
LIGHTER VALUES OF DEEP LAYER SHEAR. WOULD EXPECT SEVERE POTENTIAL
TO CONTINUE FOR BOTH WED AND THU MAINLY EAST OF THE LARAMIE RANGE
AS WELL. TROUGH WILL SWING THROUGH ON FRIDAY...DRAGGING A PACIFIC
FRONT THRU THE AREA WHICH WILL EFFECTIVELY SHUNT BEST INSTABILITY
EAST OVER CENTRAL NEBRASKA FOR BOTH FRIDAY AND SATURDAY. AS A
RESULT...EXPECT THUNDERSTORM CHANCES TO TURN MORE ISOLATED EARLY
NEXT WEEKEND. TEMPERATURES WILL BE SEASONALLY PERSISTENT THROUGH
THE PERIOD WITH 70S ON TUESDAY WARMING INTO THE 80S AT LOWER
ELEVATIONS FOR THE REMAINDER OF THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY AFTERNOON)
ISSUED AT 514 PM MDT SAT JUN 21 2014
THUNDERSTORMS MOVING THROUGH THE SOUTHERN NEBRASKA PANHANDLE EARLY
THIS EVENING SHOULD END TOWARDS SUNSET. A COLD FRONT STILL LOOKS
TO MOVE INTO THE AREA THIS EVENING...WHICH COULD PRODUCE
WIDESPREAD MVFR/IFR CONDITIONS AFTER 09Z. WILL CONTINUE TO MONITOR
THROUGH THE EVENING. THUNDERSTORMS EXPECTED TO RETURN SUNDAY
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 307 PM MDT SAT JUN 21 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. MINIMUM
RELATIVE HUMIDITY VALUES WILL BE AROUND 15 PERCENT THIS AFTERNOON
FOR AREAS TO THE WEST OF THE LARAMIE RANGE. WEST WINDS WILL GUST TO
20-25 MPH THROUGH EARLY EVENING. SINCE FUELS ARE STILL GREEN ENOUGH
TO NOT SUPPORT FIRE GROWTH...NO CRITICAL FIRE WEATHER THREAT IS
EXPECTED. COOLER TEMPERATURES ON SUNDAY THROUGH EARLY NEXT WEEK
WILL CAUSE AFTERNOON HUMIDITY VALUES TO INCREASE TO THE 20-30
PERCENT RANGE FOR AREAS TO THE WEST OF THE LARAMIE RANGE. SCATTERED
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH AFTERNOON THROUGH
THE MIDDLE OF NEXT WEEK...WITH COVERAGE HIGHEST TO THE EAST OF THE
LARAMIE RANGE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...HAHN
AVIATION...CLAYCOMB
FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
338 AM CDT SUN JUN 22 2014
.SYNOPSIS...
ISSUED AT 249 AM CDT SUN JUN 22 2014
LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH
A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE
CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL
ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN
PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB
WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING
WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA
CURRENTLY HEADED EAST-SOUTHEASTWARD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY.
RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY
OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS
LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING
AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF
THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC.
STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC.
BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST
THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY
OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER
RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA.
CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN
SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES
HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A
BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT
AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE
REGION.
DMD
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN
NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING
OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN
UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW
SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN
AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS
WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE
FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY
ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING
SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS
THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH
ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING
NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE
ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE
ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST
INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH
PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER
DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS
ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF
WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT.
TUE-TUE NGT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP
WITH WEAK SUBSIDENCE IN WAKE OF FRONT.
WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL
DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO
SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS
TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY
BY LATE WEEK AND ESPECIALLY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1159 PM CDT SAT JUN 21 2014
LIGHT WINDS AND RECENT RAINFALL MAY RESULT IN SOME MVFR FOG
OVERNIGHT. CONVECTIVE TRENDS ARE STILL VERY MUCH IN QUESTION FOR
SUNDAY AND SUNDAY NIGHT...BUT TRENDS FAVOR THE BULK OF THE
THUNDERSTORM ACTIVITY SUNDAY EVENING. HAVE OPTED FOR VCTS GROUPS
AT KBRL/KCID/KMLI AT 00Z.
&&
.HYDROLOGY...
ISSUED AT 249 AM CDT SUN JUN 22 2014
AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE
MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN
RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY
RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND
HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN
THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT
RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE
GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA.
WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS
IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY
DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE
LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY
UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE
FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT
BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD
A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS
NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS
WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO
WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION
NEXT COUPLE OF DAYS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...DMD
SHORT TERM...DMD
LONG TERM...05
AVIATION...RP KINNEY
HYDROLOGY...05
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1209 AM CDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 916 PM CDT SAT JUN 21 2014
LITTLE CHANGE FROM PREVIOUS THINKING THIS EVENING. LARGE SCALE
FORCING AHEAD OF APPROACHING CO/WY SHORT WAVES WILL KEEP SCATTERED
CONVECTION GOING IN SOME FORM UPSTREAM OVERNIGHT. SD MCS IS MOST
PRESSING CONCERN BUT SEVERE WEATHER POTENTIAL SEEMS LOW. ALTHOUGH
A FEW CELLS HAVE ACCELERATED FASTER FOR THE MOMENT...COMPLEX IS
CURRENTLY FOLLOWING CORFIDI VECTORS AS A WHOLE AND DRIFTING SE AT
15-20KTS. EXPECT THIS COMPLEX TO WEAKEN SOMEWHAT WITH
DECREASE/INCREASE IN MLCAPE/CINH RESPECTIVELY INTO THE NIGHT AND
JUST WEAK TO MODERATE EFFECTIVE SHEAR. HEAVY RAIN IS MORE OF A
CONCERN THAN SEVERE WITH ELEVATED K INDEX/PW AXIS DRIFTING EWD
INTO WRN IA COINCIDENT WITH LOW LEVEL MOISTURE FLUX AS IT MOVES
EWD WITH OVERALL SYSTEM AND VEERS. 01Z RAP CORFIDI VECTORS/MEAN
WIND ARE BOTH 15KTS OR LESS BY 09Z SO WHAT IS LEFT OF THE COMPLEX
WILL LIKELY BE SLOW MOVING. AIRMASS WILL SUPPORT EFFICIENT
RAINFALL RATES BUT PWS AND WARM CLOUD DEPTHS ARE NOT AS EXTREME AS
RECENT EVENTS.
&&
.SHORT TERM /TONIGHT/...
ISSUED AT 320 PM CDT SAT JUN 21 2014
CONVECTIVE TRENDS OVERNIGHT ARE THE PRIMARY FORECAST CHALLENGE
OVERNIGHT. MCV SHIFTING EAST ACROSS SRN WISCONSIN AND NRN ILLINOIS
HAS WRAPPED DRY MID LEVEL AIR IN TO CENTRAL AND EASTERN IOWA. THIS
HAS HELPED STRENGTHEN THE CONVECTIVE INHIBITION ACROSS THE AREA.
SFC FLOW OVER CENTRAL IOWA REMAINS NEARLY NON EXISTENT WITH THE
OVERNIGHT OUTFLOW PUSHING THE WARM FRONT JUST SOUTH INTO KANSAS
AND MISSOURI. A FEW STORMS HAVE BEEN TRYING TO INITIATE ALONG THIS
BOUNDARY BUT HAVING A DIFFICULT TIME BECOMING ORGANIZED WITH A
LACK OF DEEP LAYER SHEAR AND ANY GOOD FORCING TO AID IN SUSTAINING
UPDRAFTS. THIS ACTIVITY SHOULD MOSTLY REMAIN SOUTH OF THE STATE
BUT MAY CLIP THE SOUTHERN TIER OF COUNTIES THE NEXT FEW HOURS.
FORCING REMAINS WEAK ACROSS CENTRAL IOWA THROUGH THIS EVENING. THE
LOW LEVEL JET OF AROUND 35 KTS WILL AMPLIFY OVER THE MID MISSOURI
VALLEY AND POINTS TO THE WEST HOWEVER ITS ORIENTATION WILL FAVOR
THE FORCING AND CONVERGENCE ZONE ACROSS NEBRASKA AND SOUTH DAKOTA.
A SHORT WAVE MOVING RAPIDLY ACROSS THE ROCKIES OVERNIGHT SHOULD
SPREAD QG FORCING EAST INTO WESTERN IOWA LATE AND WILL HAVE PUSH
ANY DEVELOPING MCS CLOSE TO THE STATE LATE. POSSIBLE A FEW STORMS
DEVELOP OVER THE CENTRAL AND SOUTHWEST AS A COUPLE WAVES OF
THETA-E ADVECTION LIFT NORTH AND GENERATE AN INSTABILITY AXIS
THROUGH THAT REGION. A DISCONTINUITY BETWEEN FORCING AND MOISTURE
AVAILABLE SHOULD PREVENT WIDESPREAD ACTIVITY AHEAD OF THE WESTERN
MCS. THE THREAT FOR SEVERE WEATHER IS LOW THROUGH THE PERIOD
THOUGH CAN NOT DISCOUNT A LOCALIZED EVENT. THE THREAT FOR HEAVY
RAIN IS ALSO LOW THROUGH 12Z.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
ISSUED AT 320 PM CDT SAT JUN 21 2014
MAIN CONCERNS CONTINUE TO FOCUS ON POTENTIAL FOR HEAVY RAINFALL WITH
NEXT UPSTREAM WAVE EXPECTED TO CROSS THE REGION SUNDAY INTO EARLY
MONDAY. EXPECTING SOME LEFTOVER CONVECTION ONCE AGAIN EARLY SUNDAY
MORNING TO DECAY DURING THE MORNING HOURS ACROSS THE NORTH. A
SLIGHTLY WEAKER WAVE IS NOW EXPECTED CROSS THE REGION INTO MONDAY.
PREVIOUS MODEL SOLUTIONS SUGGESTED A STRONGER WAVE TRACKING OVER
SOUTHERN IOWA/NORTHERN MISSOURI BUT LAST 2 RUNS OF THE MODELS SHOW
SOMEWHAT OF A SPLIT NORTHERN/SOUTHERN STREAM WAVE CROSSING THE
REGION. THIS SHOULD RESULT IN A LESSER THREAT FOR WIDESPREAD HEAVY
RAIN ACROSS THE SOUTHEAST TWO THIRDS OF THE AREA FOR SUNDAY
THROUGH MONDAY...BUT INCREASE THE RISK OF RAINFALL AND SOME
LOCALLY HEAVY RAIN OVER THE NORTHERN AREAS OF THE FORECAST AREA.
BOTH THE 12Z GFS/NAM ARE NOW FAVORING THE NORTHERN STREAM ENERGY
TO DOMINATE THE NEXT 24 TO 36 HOURS...WITH WARM AIR ADVECTION AND
FRONTAL FORCING MAXIMIZED FROM NORTHWEST IOWA THROUGH SOUTHEAST
MINNESOTA AND A SECONDARY WAVE WELL SOUTH OF THE AREA. THIS LEAVES
THE BULK OF CENTRAL IOWA IN AN AREA OF LESS FAVORABLE CONVERGENCE
AND FORCING. TODAYS 12Z GEM MODEL HAS ALSO SPLIT THE ENERGY IN A
SIMILAR PATTERN...WITH SYNOPTIC DEVELOPMENT OF THE WAVES OVER
NORTHERN IOWA AND IN THE SOUTHERN PLAINS. THIS WOULD FAVOR TWO
AREAS OF HEAVIER RAINFALL...ONE OVER NORTHERN IOWA AND THE OTHER
OVER MISSOURI SOUTH TO NEAR THE OKLAHOMA/ARKANSAS BORDER. WITH THE
SUGGESTION OF SPLIT FLOW...THE PATTERN WOULD BE MORE PROGRESSIVE
WITH A QUICKER EXIT OF THE FRONT BY LATE MONDAY MORNING RATHER
THAN MONDAY NIGHT. OVERALL THIS SHOULD HELP LIMIT WIDESPREAD HEAVY
RAINFALL. HOWEVER...WE CONTINUE HAVE HIGH PRECIPITABLE WATER
VALUES OF 1.5 TO 1.75 WITH WARM CLOUD DEPTHS ONCE AGAIN RUNNING
FROM 11500 TO 13000 FT. THERE MAY STILL BE LOCALLY HEAVY RAINFALL
NEARER THE SFC LOW AS IT TRACKS ACROSS CENTRAL TO NORTHERN IOWA
WITH MORE WIDELY SCATTERED POCKETS OF LOCALLY HEAVY RAINFALL IN
THE CENTRAL AND SOUTH MAINLY DURING THE AFTERNOON AND EVENING
HOURS. HIGHS SUNDAY WILL BE VERY WARM...BUT WITH CLOUD COVER
AROUND PROBABLY HELD INTO THE LOWER TO MID 80S WITH A FEW UPPER
80S IN THE SOUTH. COOLER WEATHER WILL RETURN TOWARD MONDAY AND
TUESDAY AS THE SYSTEM PULLS EAST. TUESDAY MORNING EITHER LOOKS TO
BE A GREAT CANDIDATE FOR FOG OR A LOT OF DEW. WILL NEED TO TAKE A
LOOK AT THIS IN THE NEXT PACKAGE OR TWO AS WINDS BECOME VERY LIGHT
BY THAT TIME AND TEMPERATURES RADIATE BACK INTO THE LOWER 60S.
THERE REMAINS A WEAK SIGNAL FOR SOME SHOWERS TUESDAY OR WEDNESDAY
OVER THE NORTH AND WEDNESDAY OVER THE CENTRAL. FOR NOW...GREATER
UNCERTAINTY ABOUT CHANCES FOR RETURN MOISTURE THAT SOON...AND THIS
MAY CHANGE. BY MID TO LATE IN THE PERIOD A WEST SOUTHWEST FLOW
WILL RETURN ALOFT. THIS WILL PROMOTE WARMER TEMPERATURES AND
INCREASED CHANCES FOR THUNDERSTORMS. HIGHS THROUGH MIDWEEK WILL
REMAIN IN THE LOWER 80S WITH LOWS IN THE 60S. BY LATE IN THE
PERIOD MID 80S ARE MORE LIKELY WITH LOWS IN THE UPPER 60S TO LOWER
70S. AS TEMPS WARM ALOFT AT H700 TO ABOVE 10C...THUNDERSTORM
CHANCES MAY BE CAPPED BUT UNCERTAINTY INCREASES TOWARD THE END OF
THE EXTENDED FORECAST.
&&
.AVIATION...22/06Z
ISSUED AT 1209 AM CDT SUN JUN 22 2014
VFR CONDITIONS ARE ANTICIPATED INTO SUN MORNING WITH ATTENTION
TURNING UPSTREAM INTO SD FOR CONVECTIVE TRENDS. SHOWERS AND
STORMS ARE POSSIBLE FOR A PERIOD BEFORE DAYBREAK...WITH BETTER
LIKELIHOOD NW VS SE. RESTRICTIONS ARE POSSIBLE WITH HEAVIER RAIN
SHOWERS BUT LIKELIHOOD AT ANY PARTICULAR TAF SITES IS QUITE LOW.
SURFACE BASED CONVECTION IS ALSO POSSIBLE LATER IN THE DAY. HAVE
FAIRLY HIGH CONFIDENCE IN PRECIP SOMETIME SUN MIDDAY INTO THE
EVENING...BUT TIMING AND LOCATIONS HAVE LITTLE PREDICTABILITY AT
THIS POINT SO HAVE NOTHING MORE THAN PROLONGED VFR VCSH WORDING
FOR NOW.
&&
.HYDROLOGY...
ISSUED AT 320 PM CDT SAT JUN 21 2014
TONIGHT THROUGH MONDAY NIGHT
THE MAIN CONCERN LATE TONIGHT AND EARLY SUNDAY WILL BE MCS
DEVELOPMENT OVER THE WESTERN PLAINS...MOVING EAST INTO NORTHWEST
IOWA BY MORNING. THIS ACTIVITY SHOULD DECAY EARLY IN THE DAY BUT
AS THE MAIN SHORTWAVE MOVES ACROSS THE AREA SUNDAY...THUNDERSTORMS
WILL INCREASE IN COVERAGE. WITH PWATS CONTINUING HIGH AND WARM
CLOUD DEPTHS FAVORING EFFICIENT RAINFALL PROCESSES...SOME AMOUNTS
OF 1 TO 2 INCHES IN A SHORT PERIOD OF TIME WILL BE POSSIBLE SUNDAY
INTO SUNDAY EVENING ESPECIALLY. MOST 1 AND 3 HOUR GRIDDED FLASH
FLOOD GUIDANCE OVER THE REGION IS ABOUT 1 TO 2 INCHES...SO IF ANY
STORMS WITH HIGH RAINFALL RATES DEVELOP...THERE WILL BE A
POTENTIAL FOR SOME LOCALIZED FLOODING ISSUES. ONE LIMITING FACTOR
SUNDAY WILL BE A SLIGHTLY MORE PROGRESSIVE WAVE AS THE MAIN
SHORTWAVE TRACKS EAST. CONFIDENCE OF OVERALL COVERAGE AND LOCATION
IS LOW ENOUGH TO LEAVE HEADLINES OUT FOR NOW. RIVER LEVELS WILL
RESPOND AGAIN TO ANY ADDITIONAL RAINFALL OVER OUR FORECAST AREA
SUNDAY AND SUNDAY EVENING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...DONAVON
LONG TERM...REV
AVIATION...SMALL
HYDROLOGY...REV
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1153 PM CDT Sat Jun 21 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Sunday)
Issued at 315 PM CDT SAT JUN 21 2014
19Z water vapor imagery continues to shows a quasi-zonal flow across
the central Rockies and into the plains. There may be one or two
Mesoscale Convective Vortices (MCV) moving along the KS/NEB state
line with the more obvious one crossing the MO river and headed into
central MO. There also appears to be a subtle shortwave moving
through ID and northern UT. At the surface, a trough of low pressure
extended from the Dakotas south through eastern CO. Surface OBS show
the better low level moisture has shifted a little to the east with
much of the 70 degree dewpoints.
Late this afternoon and this evening is anticipated to be mostly dry
with general subsidence from the MCV over eastern KS and the deeper
moisture to the east of the area. This combined with a lack of
organized low level convergence should favor any isolated storms
remaining east of the forecast area. Will have to watch and see if
any of the convection off the higher terrain holds together long
enough to reach north central KS. There are some indications from
the RAP and HRRR that there could be some precip move into Republic
and Cloud counties around midnight. However those solutions seem to
be a little to aggressive in developing convection earlier in the
day, so I don`t know how much weight to give these solutions. Will
have some small POPs after midnight for far northern counties in
case some shower and thunderstorm activity is able to hang together.
Lows tonight should once again be mild with readings around 70 due to
southerly winds and warm air remaining over the area.
For Sunday, the subtle shortwave out west is progged to be moving
out into the plains, mainly to the north of the forecast area.
However the synoptic scale surface trough is expected to be a little
further east into KS. Convergence along this boundary coupled with
some weak forcing from the upper wave could cause a broken line of
storms to form by the afternoon hours. Instability is expected to be
high once again with good low level moisture still in place. However
due to weak mid level flow, deep layer shear is progged to only be
from 15 to 25 kts. This would favor multi cell clusters with a hail
and strong wind hazard. North central KS looks like the most likely
place for this storms to form during the afternoon. Temps for Sunday
are expected to be similar to today`s or maybe a degree or two
cooler. Models show a slight cooling trend at 850 and there could be
higher clouds increasing by the afternoon from the potential
convection to the west. Because of this have highs generally in the
lower 90s.
.LONG TERM...(Sunday Night through Saturday)
Issued at 315 PM CDT SAT JUN 21 2014
Overall trend is for the upper wave to be less intense as it passes
through Sunday night into early Monday. Still looks like a good
opportunity for for most locations to receive at least one round of
precip with the slow moving system weak front moving through a moist
early-summer airmass and limited inhibition. Severe weather concerns
should diminish with time in the evening hours with a least some
chance for pockets of heavier precipitation, though setup does not
point to any particularly area at this point. Monday should slowly dry
with the departing wave with Monday night and much of Tuesday still
looking to be the more likely dry periods of this forecast.
Models do show some similarities with a weak wave passing mainly
south of the area late Tuesday into Wednesday, but moisture does
return north with this wave with modest flow keeping mid levels from
warming too fast for at least small thunderstorm chances. Upper flow
amplifies over the western and eventually central CONUS into the end
of the forecast. Expect capping to increase enough for a mainly dry
end to the work week with chances picking up again by Saturday as
forcing increases. Temps should slowly warm through the latter
portions of the week, with 90s possible by Saturday.
&&
.AVIATION...(For the 06Z TAFs through 06Z Sunday Night)
Issued at 1146 PM CDT SAT JUN 21 2014
VFR conditions expected through mid day today. A boundary will
approach from central KS during the evening hours causing
widespread thunderstorms late in the period. There is also the
possibility of isolated to scattered storms out ahead of the
boundary near the taf sites in the late afternoon due to daytime
heating. The lift for this convection could be enhanced by a shortwave
although the there is a lack of surface convergence. Timing of the
shortwave and any outflow that could potential contribute to convergence
at the surface is uncertain and will need time to evaluate.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS JACKSON KY
402 AM EDT SUN JUN 22 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 355 AM EDT SUN JUN 22 2014
THE PATTERN ACROSS THE CONUS REMAINS RATHER ZONAL THIS MORNING. AN
UPPER LEVEL RIDGE WAS CENTERED OVER THE WESTERN GULF OF MEXICO REGION
AND SOUTHEASTERN CONUS AND EXTENDED INTO THE MS VALLEY. A TROUGH IS GRADUALLY
DEPARTING THE NORTHEASTERN CONUS. THIS PUTS THE REGION IN WEST
NORTHWEST TO NORTHWEST FLOW ALOFT WITH MAINLY CIRRUS DROPPING ACROSS
THE AREA. PATCHY DENSE VALLEY FOG HAS FORMED IN VALLEY LOCATIONS AND
BASED ON RECENT ASOS AND AWOS OBS MAY BE A BIT MORE WIDESPREAD IN
PARTS OF THE CUMBERLAND VALLEY.
SO FAR AN SPS HAS BEEN ISSUED FOR THE DENSE FOG ACROSS THE SOUTHWEST
PART OF THE CWA. THIS WILL CONTINUE TO BE MONITORED OVER THE NEXT FEW
HOURS. FOG SHOULD GRADUALLY BEGIN TO LIFT AFTER SUNRISE AND DISSIPATE
BY AROUND 9 TO 10 AM.
OTHERWISE...A COUPLE OF WEAK SHORTWAVES ARE EXPECTED TO WORK ACROSS
THE OH VALLEY AND EASTERN KY THIS AFTERNOON AND THIS EVENING. AT THE
SAME TIME...THE BOUNDARY THAT SAGGED SOUTH INTO THE AREA WILL REMAIN
NEARLY STATIONARY OVER THE SOUTHWEST PART OF THE CWA...OR JUST TO
THE SOUTH AND WEST OF THAT REGION. DRIER DEWPOINTS ACROSS THE
NORTHERN AND EASTERN PART OF THE CWA MAY INITIALLY INHIBIT CONVECTION
A BIT...AS POSSIBLY THE MID LEVEL RIDGING TO OUR WEST. RECENT RUNS OF
THE RAP HAVE CONVECTION DEVELOPING NORTHWEST OF THE AREA IN THE
AFTERNOON AND APPROACHING THE AREA TOWARD SUNSET...BUT TENDS OF
WEAKEN IT LATE. THE 0Z NAM BRINGS SOME CONVECTION ACROSS THE REGION
AROUND SUNSET AND THE 0Z GFS IS RATHER SIMILAR. WITH THE BOUNDARY IN
THE VICINITY AND THE FACT THAT FORECAST SOUNDINGS GENERALLY DO NOT
INDICATE THAT THERE WILL BE SIGNIFICANT CAPPING...BUT FORCING WILL BE
RATHER WEAK OPTED TO CONTINUE WITH SLIGHT CHANCES FROM MID AFTERNOON
INTO THE EVENING HOURS.
THEREAFTER...A DIURNAL INCREASE IN CONVECTION IS ANTICIPATED
OVERNIGHT TONIGHT...AS THE MID LEVEL RIDGING BUILDS IN AND HEIGHTS
RISE FURTHER. PATCHY VALLEY FOG SHOULD AGAIN DEVELOP. THE MID LEVEL
RIDGING SHOULD GRADUALLY SHIFT EAST OF THE AREA ON MONDAY WITH A
SHORTWAVE TROUGH APPROACHING FROM THE WEST. THIS SHOULD ALSO LEAD TO
THE STATIONARY BOUNDARY LIFTING ACROSS THE AREA AS A WARM FRONT.
850 MB TEMPS SHOULD CLIMB TOWARD AT LEAST 18C. WIDESPREAD LOWER 90S
ARE EXPECTED FOR HIGHS OUTSIDE OF THE HIGHER TERRAIN. THE LIFTING WARM
FRONT AND HEIGHT FALLS LATE SHOULD COMBINE WITH DAYTIME HEATING FOR
SCATTERED CONVECTION...ESPECIALLY FROM MID AFTERNOON INTO THE EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 402 AM EDT SUN JUN 22 2014
THE PATTERN ACROSS THE CONUS CONTINUES A MAINLY ZONAL FLOW ACROSS
THE NORTHERN PART OF THE COUNTRY WITH WEAKENED RIDGING OVER THE
SOUTH. THIS IS MAINTAINED...AT LEAST FOR THE FIRST HALF OF THE
EXTENDED. ON TUESDAY...A SEEMINGLY WEAKER SHORTWAVE FROM RUN TO RUN
TRIES TO PUSH ACROSS THE LOWER GREAT LAKES AND AT THE
SURFACE...BRINGS A WEAK COLD FRONT ACROSS THE OH VALLEY. TOWARDS THE
LAST FEW DAYS OF THE EXTENDED...THE PATTERN BEGINS TO TRANSITION TO
A MORE AMPLIFIED PATTERN WITH DEVELOPING RIDGING ALONG THE MS RIVER
VALLEY AND TROUGHS DIGGING ALONG THE THE WEST COAST AND ALSO ALONG
THE EAST COAST. ONE SLIGHT CHANGE IN RECENT RUNS SHOWS A WAVE UNDER
CUTTING THE RIDGE AND DRIFTING INTO THE MID MS VALLEY AND INTO THE
TN VALLEY BY THE END OF THE EXTENDED.
OTHERWISE...THROUGH THE EXTENDED...A WARM...MOIST...AND UNSTABLE AIR
MASS REMAINS OVER EASTERN KENTUCKY. THIS WILL CONTINUE THE AFTERNOON
MAXIMUM CHANCE FOR PRECIP DWINDLING TO THE MINIMUM CHANCE OF PRECIP
INTO THE OVERNIGHT HOURS. THE ONE CHANCE OF DISRUPTING THIS TREND
WOULD BE THE ARRIVAL OF AN MCS THROUGH THE AREA...WHICH IS A
POSSIBILITY. OTHERWISE...DID NOT STRAY FROM THE MODEL ALL BLEND.
THIS PATTERN MAY BE COMING TO AN END BY THE END OF THE EXTENDED WITH
THE MODELS HINTING AT STRONG RIDGING BUILDING AND SHIFTING EAST OF
THE MS. OTHERWISE...HUMID...WARM...AND UNSTABLE DAYS ARE TO
CONTINUE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 155 AM EDT SUN JUN 22 2014
THERE SHOULD BE AN OVERALL DECREASE IN CLOUD COVER THROUGH
12Z...ESPECIALLY ANY MID OR LOW CLOUDS...THOUGH BANDS OF MID AND HIGH
CLOUDS SHOULD PASS FROM TIME TO TIME INTO SUNDAY. PATCHY VALLEY FOG
SHOULD ALSO GRADUALLY DEVELOP THROUGH 9Z AT LOZ...SME AND PROBABLY
LIFT INTO SJS. THE MOST IMPACTED AIRPORTS BEING KLOZ AND KSME WHERE
RAIN HAD FALLEN EARLIER IN THE DAY. WITH A LARGER CURRENT DEWPOINT
DEPRESSION AT JKL..LEFT OUT ANY FOG THERE. THE FOG WILL LIFT AND
DISSIPATE BY ABOUT 13Z. WITH DAYTIME HEATING...INSTABILITY WILL
INCREASE AND THE THREAT OF AN ISOLATED SHRA OR TSRA AFTER 16Z...BUT
PROBABILITIES AND CONFIDENCE IN THIS IS TOO LOW TO INCLUDE ATTM.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
401 AM EDT SUN JUN 22 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 355 AM EDT SUN JUN 22 2014
THE PATTERN ACROSS THE CONUS REMAINS RATHER ZONAL THIS MORNING. AN
UPPER LEVEL RIDGE WAS CENTERED OVER THE WESTERN GULF OF MEXICO REGION
AND SOUTHEASTERN CONUS AND EXTENDED INTO THE MS VALLEY. A TROUGH IS GRADUALLY
DEPARTING THE NORTHEASTERN CONUS. THIS PUTS THE REGION IN WEST
NORTHWEST TO NORTHWEST FLOW ALOFT WITH MAINLY CIRRUS DROPPING ACROSS
THE AREA. PATCHY DENSE VALLEY FOG HAS FORMED IN VALLEY LOCATIONS AND
BASED ON RECENT ASOS AND AWOS OBS MAY BE A BIT MORE WIDESPREAD IN
PARTS OF THE CUMBERLAND VALLEY.
SO FAR AN SPS HAS BEEN ISSUED FOR THE DENSE FOG ACROSS THE SOUTHWEST
PART OF THE CWA. THIS WILL CONTINUE TO BE MONITORED OVER THE NEXT FEW
HOURS. FOG SHOULD GRADUALLY BEGIN TO LIFT AFTER SUNRISE AND DISSIPATE
BY AROUND 9 TO 10 AM.
OTHERWISE...A COUPLE OF WEAK SHORTWAVES ARE EXPECTED TO WORK ACROSS
THE OH VALLEY AND EASTERN KY THIS AFTERNOON AND THIS EVENING. AT THE
SAME TIME...THE BOUNDARY THAT SAGGED SOUTH INTO THE AREA WILL REMAIN
NEARLY STATIONARY OVER THE SOUTHWEST PART OF THE CWA...OR JUST TO
THE SOUTH AND WEST OF THAT REGION. DRIER DEWPOINTS ACROSS THE
NORTHERN AND EASTERN PART OF THE CWA MAY INITIALLY INHIBIT CONVECTION
A BIT...AS POSSIBLY THE MID LEVEL RIDGING TO OUR WEST. RECENT RUNS OF
THE RAP HAVE CONVECTION DEVELOPING NORTHWEST OF THE AREA IN THE
AFTERNOON AND APPROACHING THE AREA TOWARD SUNSET...BUT TENDS OF
WEAKEN IT LATE. THE 0Z NAM BRINGS SOME CONVECTION ACROSS THE REGION
AROUND SUNSET AND THE 0Z GFS IS RATHER SIMILAR. WITH THE BOUNDARY IN
THE VICINITY AND THE FACT THAT FORECAST SOUNDINGS GENERALLY DO NOT
INDICATE THAT THERE WILL BE SIGNIFICANT CAPPING...BUT FORCING WILL BE
RATHER WEAK OPTED TO CONTINUE WITH SLIGHT CHANCES FROM MID AFTERNOON
INTO THE EVENING HOURS.
THEREAFTER...A DIURNAL INCREASE IN CONVECTION IS ANTICIPATED
OVERNIGHT TONIGHT...AS THE MID LEVEL RIDGING BUILDS IN AND HEIGHTS
RISE FURTHER. PATCHY VALLEY FOG SHOULD AGAIN DEVELOP. THE MID LEVEL
RIDGING SHOULD GRADUALLY SHIFT EAST OF THE AREA ON MONDAY WITH A
SHORTWAVE TROUGH APPROACHING FROM THE WEST. THIS SHOULD ALSO LEAD TO
THE STATIONARY BOUNDARY LIFTING ACROSS THE AREA AS A WARM FRONT.
850 MB TEMPS SHOULD CLIMB TOWARD AT LEAST 18C. WIDESPREAD LOWER 90S
ARE EXPECTED FOR HIGHS OUTSIDE OF THE HIGHER TERRAIN. THE LIFTING WARM
FRONT AND HEIGHT FALLS LATE SHOULD COMBINE WITH DAYTIME HEATING FOR
SCATTERED CONVECTION...ESPECIALLY FROM MID AFTERNOON INTO THE EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 359 AM EDT SUN JUN 22 2014
THE LONG TERM DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 155 AM EDT SUN JUN 22 2014
THERE SHOULD BE AN OVERALL DECREASE IN CLOUD COVER THROUGH
12Z...ESPECIALLY ANY MID OR LOW CLOUDS...THOUGH BANDS OF MID AND HIGH
CLOUDS SHOULD PASS FROM TIME TO TIME INTO SUNDAY. PATCHY VALLEY FOG
SHOULD ALSO GRADUALLY DEVELOP THROUGH 9Z AT LOZ...SME AND PROBABLY
LIFT INTO SJS. THE MOST IMPACTED AIRPORTS BEING KLOZ AND KSME WHERE
RAIN HAD FALLEN EARLIER IN THE DAY. WITH A LARGER CURRENT DEWPOINT
DEPRESSION AT JKL..LEFT OUT ANY FOG THERE. THE FOG WILL LIFT AND
DISSIPATE BY ABOUT 13Z. WITH DAYTIME HEATING...INSTABILITY WILL
INCREASE AND THE THREAT OF AN ISOLATED SHRA OR TSRA AFTER 16Z...BUT
PROBABILITIES AND CONFIDENCE IN THIS IS TOO LOW TO INCLUDE ATTM.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1252 AM EDT Sun Jun 22 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 917 PM EDT Sat Jun 21 2014
Ran another update this evening mainly to bring grids up to speed
with current observations. As expected, convection is rapidly
weakening off to the northwest as the precipitation encounters a
much drier and more stable airmass. Therefore, will continue to
leave the forecast dry overnight. Also went ahead and added some
patchy fog to the grids across the Lake Cumberland region where the
heaviest rainfall fell this afternoon/evening. Otherwise, the rest
of the forecast looks on track.
Issued at 614 PM EDT Sat Jun 21 2014
Quick update this evening to account for ongoing trends. Despite a
few very isolated light showers, precipitation has ended across
southern KY. Therefore, will remove precip mention from the
forecast for the remainder of the evening hours. Attention will
then turn to the northwest as a line of showers and thunderstorms
continues to develop across IL/MO. The main forecast challenge
tonight will be just how far east that convection makes it. Given
it will be fighting much drier air that has protruded into southern
IN and into southern IL, think this convection will likely struggle
as it pushes east. However, the latest HRRR which has a good handle
on the current convection, does bring a weakening line into southern
IN around 06Z overnight. Given the drier air firmly in place, will
continue with a dry forecast but will continue to monitor trends
over the next few hours.
.SHORT TERM (Now through Sunday Night)...
Issued at 300 PM EDT Sat Jun 21 2014
The upper air pattern shows a progressive relatively flat flow at
500mb confined generally to the northern tier of states. Weak
northwest flow currently over the northern Ohio Valley will become
weaker as ridging is forecast to develop across the Lower
Mississippi Valley by late Sunday, extending northeastwards through
southern Indiana.
Expect only a few flat cumulus this afternoon along and north of
Interstate 64 as the shortwave that brought scattered thunderstorms
earlier this morning to the Lake Cumberland Region moves farther
southeast. Any additional isolated thunderstorms through late
afternoon will stay along and southeast of the Cumberland Parkway.
Expect mostly clear skies tonight with humid conditions and light
winds. Some patchy fog may once again develop across southern
Indiana and the Bluegrass Region, although not to the extent of
earlier this morning. Lows tonight will range from the mid 60s
across the Bluegrass and southern Indiana to near 70 elsewhere.
Despite adequate moisture and quite unstable conditions developing
Sunday afternoon, ridging aloft will inhibit any widespread
convection. Think that scattered thunderstorms may develop farther
north across Illinois and Indiana, with isolated storms at best
along and north of the Ohio River. Expect south central Kentucky to
stay dry. Highs Sunday will range from the upper 80s northeast to
the lower 90s southwest. Light south winds will develop Sunday
afternoon.
.LONG TERM (Monday through Saturday)...
Issued at 255 PM EDT Sat Jun 21 2014
Fairly typical summertime conditions expected for most of the
upcoming week, with a low-amplitude and somewhat progressive pattern
aloft.
Shortwave ridging on Monday will most likely allow for the warmest
temps of the week. However, the pattern is still just flat enough
and heights not getting into legitimate heat wave territory, so
expect temps to reach the lower 90s in most spots. This stays in
line with the more consistent and slightly cooler NAM MOS. Chance
POPs will re-enter the picture Monday afternoon as the ridging
begins to gradually weaken.
Best chance for showers and storms will be Tuesday into Tuesday
night, with the passage of an upper shortwave trof. High PWATs will
support a heavy rain and pulse wind threat.
The rest of the week will not see any real pattern change, but just
warm and humid conditions with isolated/scattered storms each day,
mainly in the afternoons.
Pattern aloft starts to amplify toward the end of the week with a
ridge nosing up into the Upper Midwest. This bears watch for a
possible break in our daily convection and temps possibly punching
back into the 90s at some point next weekend.
&&
.AVIATION (06Z TAF Update)...
Issued at 1250 AM EDT Sun Jun 22 2014
Skies will be variably cloudy overnight as some upper level debris
from earlier convection moves overhead. Meanwhile, high pressure
will be in control at the surface with mostly calm winds. Will
continue to leave mention of some MVFR fog at BWG/LEX toward dawn,
although the variable cloudiness could limit potential somewhat. GLW
has already dropped to 7SM adding confidence that it should be left
in.
Otherwise, expect light winds later today, with any noticeable
gradient out of the SW. Conditions will become unstable in the
afternoon although thunderstorm coverage is expected to be limited
to isolated due to the upper ridge overhead. Do expect few-sct Cu
around 5 K feet in the afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........KJD
Short Term.....JSD
Long Term......RAS
Aviation.......BJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
525 AM EDT SUN JUN 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT SUN JUN 22 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER
CNTRL SASK/MANITOBA AND A DOWNSTREAM RIDGE FROM THE NRN LAKES TO
JAMES BAY. AT THE SFC...TROUGH EXTENDED INTO THE ERN DAKOTAS AND
CNTRL NEBRASKA FROM LOW PRES NEAR LAKE WINNIPEG WHILE HIGH PRES
PREVAILED TO THE EAST FROM SRN QUEBEC INTO THE NRN LAKES. A SHRTWV
TROUGH AHEAD OF THE MID LEVEL LOW SUPPORTED SOME SHRA/TSRA FROM NW
ONTARIO TO NEAR KELO. HOWEVER...THE STRONGER AND MORE WIDEPSREAD
CONVECTION WAS WELL TO THE SOUTH FROM ERN NEBRASKA INTO WRN IA WHERE
THE MORE FAVORABLE INSTABIILITY (MUCPAE TO NEAR 2K J/KG) AND
MOISTURE TRANSPORT WAS LOCATED. OTHERWISE...MAINLY LOW STRATUS
PREVAILED ACROSS MUCH OF WEST AND CENTRAL UPPER MI WHERE LOW LEVEL
MOISTURE REMAINS BELOW THE 925 MB INVERSION.
TODAY...EXPECT THAT THE SHRA/TSRA ASSOCIATED WITH THE MODEST FORCING
ASSOCIATED WITH THE NW ONTARIO SHRTWV WILL WEAKEN AS IT MOVES TOWARD
THE RIDGE. DAYTIME HEATING SHOULD BREAK UP THE LOWER CLOUDS SO THAT
AFTERNOON SUNSHINE WILL PUSH TEMPS INTO THE LOWER 80S INLAND WHILE
LAKE BREEZES LIMIT READINGS TO THE 60S NEAR THE GREAT LAKES. THE NAM
AND SEVERAL HIGHER RES MODELS SUGGEST THAT THERE WILL BE ENOUGH
INSTABILITY FOR SOME SHRA/TSRA OVER MAINLY THE WEST THIRD DURING THE
AFTERNOON. HOWEVER...SINCE MORE MODEST MLCAPE VALUES INTO THE
300-600 J/KG RANGE ARE EXPECTED AND LARGE SCALE FORCING IS NOT
FCST...CONFIDENCE FOR SHRA/TSRA DEVELOPMENT IS LOW AND ONLY SLIGHT
CHANCE POPS WERE INCLUDED.
TONIGHT...ANY CONVECTION THAT DEVELOPS DURING THE AFTERNOON WILL
DIMINISH DURING THE EVENING. HOWEVER...AS THE TROUGH AND FRONTAL
BOUNDARY EDGE TOWARD THE WRN CWA OVERNIGHT...SHRA/TSRA CHANCES WILL
INCREASE AS ADDITIONAL WEAK SHORTWAVES EMERGE FROM THE PLAINS. THERE
IS LESS CONFIDENCE IN THE EASTWARD EXTENT OF THE PCPN AS THE RIDGE
TO THE EAST LIMITS THE MOVEMENT OF THE MOISTURE AXIS TO THE EAST. IN
ADDITION...ANOTHER ROUND OF STRONGER CONVECTION IS MORE LIKELY OVER
NRN IA OR SRN MN INTO SRN WI THAT WOULD LIMIT MOISTURE TRANSPORT TO
THE NORTH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 509 AM EDT SUN JUN 22 2014
MONDAY CONTINUES TO LOOK LIKE A SHOWERY DAY ACROSS MUCH OF THE
WESTERN HALF OF UPPER MICHIGAN AS THE UPPER LOW OVER
MANITOBA/SASKATCHEWAN FINALLY OPENS UP AND SLOWLY MOVES EASTWARD.
MEANWHILE...A WEAK UPPER SHORT WAVE OVER THE CENTRAL PLAINS MOVES
TOWARD THE REGION. THESE TWO FEATURES WILL WILL ALLOW FOR WEAK LOW
PRESSURE TO DEVELOP OVER THE MID MS VLY AND MOVE TOWARD THE GREAT
LAKES. MOISTURE AND WARM ADVECTION AHEAD OF THE TROUGH WILL SPREAD
ACROSS THE AREA MONDAY AND BE SLOW TO MOVE OUT UNTIL THE LOW PASSES
BY TUE. EXPECT SHOWERS AND ISOLATED STORMS TO DEVELOP ACROSS THE
WESTERN U.P. MON MORNING THEN SLOWLY SPREAD EASTWARD DURING THE DAY
AS THE 850MB TROUGH AND ASSOCIATED MOISTURE CONVERGENCE MOVES EAST.
WITH THE COMBINATION OF THE FAVORABLE DYNAMICS FROM THE SHORT WAVE
ENERGY AS WELL AS HIGH MOISTURE CONTENT OF THE ATMOSPHERE
/PRECIPITABLE WATER VALUES AROUND 1.75 INCHES/...EXPECT A FEW AREAS
ACROSS THE WEST HALF TO SEE 0.50 TO 1.0 INCHES OF RAIN MONDAY UNDER
THE HEAVIEST AND MOST PERSISTENT SHOWER ACTIVITY. AS SUCH...WILL
KEEP LIKELY POPS ACROSS THE ENTIRE WESTERN HALF OF THE FORECAST AREA
ON MONDAY. FUTURE SHIFTS WILL LIKELY NEED TO RAISE POPS MORE...BUT
THERE IS STILL SOME UNCERTAINTY EXACTLY WHERE THE BEST RAIN WILL SET
UP.
AS THE LOW MOVES SOUTH OF THE AREA MONDAY NIGHT...THE COLD FRONT
ASSOCIATED WITH THE NORTHERN STREAM ENERGY WILL DIVE SOUTHWARD.
MOISTURE WILL PERSIST ACROSS MUCH OF THE EASTERN HALF OF UPPER
MICHIGAN MONDAY NIGHT COMBINED WITH SYNOPTIC FORCING FROM THE UPPER
TROUGH. AS SUCH...WILL MAINTAIN LIKELY POPS EAST FOR MONDAY NIGHT
TAPERING TO CHANCE POPS FOR THE WEST.
TUESDAY MAY END UP BEING A FAIRLY RAW DAY ACROSS AT LEAST THE
NORTHERN HALF OF UPPER MI WITH NORTHERLY FLOW BEHIND THE LOW
COMBINED WITH SCATTERED SHOWERS DUE TO THE CONTINUE 850MB BAROCLINIC
ZONE ACROSS THE AREA AND DEEP MOISTURE. WILL MAINTAIN CHANCE POPS
ACROSS THE ENTIRE AREA ALTHOUGH CLOSER TO LAKE SUPERIOR MAY SEE MORE
DRIZZLE THAN ANYTHING. AREAS CLOSE TO LAKE SUPERIOR MAY STRUGGLE TO
RISE OUT OF THE MID 50S ON TUESDAY ALTHOUGH INLAND AREAS WILL SEE
TEMPS RISE WELL INTO THE 60S.
FOR TUE NIGHT/WED...HIGH PRESSURE BUILDS ACROSS THE AREA LEADING TO
A DRY PERIOD THROUGH WED NIGHT. HIGH PRESSURE HANGS ON THRU THU
ALTHOUGH THE ECMWF AND GFS BOTH SUGGEST ANOTHER SHORT WAVE MOVING
INTO THE UPPER LAKES DURING THE DAY WHICH MAY ALLOW FOR SHOWERS AND
ISOLATED STORMS DURING THE AFTERNOON. UPPER RIDGING FINALLY BUILDS
IN FOR THE WEEKEND WHICH MEANS TEMPERATURES RISING TO ABOVE NORMAL.
MAY BE A CHANCE FOR RAIN FRI NIGHT INTO SATURDAY AS WEAK WARM
ADVECTION DEVELOPS...BUT LATEST ECMWF SUGGESTS THAT THE RAIN CHANCES
WILL HOLD OFF UNTIL SAT NIGHT/SUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 127 AM EDT SUN JUN 22 2014
WITH LINGERING LLVL MSTR UNDER MID LVL SUBSIDENCE/DRYING...EXPECT
WIDESPREAD STATUS AND FOG IN THE PRESENCE OF NOCTURNAL COOLING TNGT.
IFR/LIFR CONDITIONS WL BE THE RULE...WITH EVEN VLIFR/BLO LANDING
MINIMUM CONDITIONS AT CMX WITH AN E UPSLOPE WIND. NOT OUT OF THE
QUESTION THERE COULD BE BLO LANDING MIN CONDITIONS AT SAW AND IWD
TOO. THE COMBINATION OF DAYTIME HEATING AND SOME LLVL DRYING WL
ALLOW THE FOG/STRATUS TO BURN OFF AND CONDITIONS TO TRANSITION
GRADUALLY TO VFR BY NOON. MORE FOG AND LO CLDS COULD ROLL IN OFF LK
SUP THIS EVNG AT CMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SUN JUN 22 2014
DENSE FOG WILL CONTINUE TO BE THE MAIN CONCERN ACROSS WEST AND
CENTRAL LAKE SUPERIOR. LINGERING LOW LEVEL MOISTURE WITH PERSISTENT
LIGHT E OR SE LOW LEVEL FLOW WILL ALLOW FOR DENSE FOG WILL HELP TO
MAINTAIN THE FOG OR LOW STRATUS TODAY. THERE MAY BE ENOUGH DRY AIR
MOVING IN THIS AFTERNOON TO MIX OUT THE FOG BUT THERE IS THE
POSSIBILITY THAT AN EXTENSION OF THE DENSE FOG ADVISORY MAY BE
NEEDED. WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH THIS
FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING FOR
LSZ162-240>248-263>265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
316 AM EDT SUN JUN 22 2014
.SYNOPSIS...
ISSUED AT 314 AM EDT SUN JUN 22 2014
NORTHERN MICHIGAN WILL REMAIN BETWEEN HIGH PRESSURE SINKING INTO
THE EASTERN GREAT LAKES TODAY...AND LOW PRESSURE OVER THE UPPER
MISSISSIPPI VALLEY. THERE WILL BE A FEW SHOWERS THIS MORNING...BUT A
BETTER SHOT OF SHOWERS AND THUNDERSTORMS...WILL ARRIVE LATER MONDAY
AND MONDAY NIGHT.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 314 AM EDT SUN JUN 22 2014
...SOME SPOTTY SHOWERS THIS MORNING...
HIGH IMPACT WEATHER POTENTIAL: PATCHY FOG DEVELOPING AFTER MIDNIGHT
SUNDAY NIGHT/MONDAY MORNING.
PATTERN SUMMARY/IMPLICATIONS: VERY SIMILAR STORY TO WHAT WE
DISCUSSED 24 HOURS AGO WITH CLOSED LOW SITTING OVER
MANITOBA/SASKATCHEWAN WITH DOWNSTREAM RIDGING OVER MICHIGAN NORTH
INTO ONTARIO SQUEEZED AGAINST LARGER SCALE TROUGHING OVER EASTERN
CANADA. SHORTWAVES CONTINUE TO SHEAR OUT AS THEY RUN INTO THE
OVERHEAD RIDGE AXIS...WITH THE MOST RECENT WAVE OF DEEP MOISTURE NOW
BEGINNING TO PULL EAST OF THE STATE. DRILLING DOWN TO THE SURFACE
ALSO REVEALS STRONG SIMILARITY TO ONE DAY AGO WITH HIGH PRESSURE
ANCHORED OVER HUDSON BAY AND A SURFACE LOW BENEATH THE CLOSE FEATURE
OVER MANITOBA. BETWEEN THESE FEATURES...A PLUME OF DEEPER MOISTURE
REMAINS STALLED OVER NORTHERN MICHIGAN. WEAK POSITIVE THETAE
ADVECTION AT H8 CONTINUES TO FORCE SHRAS PRIMARILY OVER THE
NORTHEASTERN HALF OF THE CWA. GIVEN THE STAGNANT NATURE OF THE
PATTERN...FORECAST CHALLENGES WILL CONTINUE TO REVOLVE AROUND LIGHT
PRECIPITATION POTENTIAL WITH ASSOCIATED CLOUDS/IMPACTS ON
TEMPERATURES.
TODAY...
PRECIPITATION CHANCES: OVERHEAD H8 THETAE GRADIENT STALLS OVER
EASTERN CHIP/MACK SOUTH AND EAST ACROSS NORTHEAST LOWER THROUGH NOON
BEFORE BEING PUSHED NORTH AND EAST. WITH DEEP MOISTURE WANING /SEE
CURRENT WV IMAGERY/...EXPECT COVERAGE IN SHOWER ACTIVITY ASSOCIATED
WITH THIS GRADIENT TO WEAKEN...BUT LIKELY NOT QUIT THROUGH THE
MORNING HOURS...WARRANTING A CHANCE POP/SCATTERED WORDING HERE. AS
WE LOOK INTO THE AFTERNOON...FOCUS TURNS TO POPPING ANY DIURNAL
CONVECTION WITH A SOMEWHAT MOISTER LLEVEL AIRMASS THAN 24 HOURS
PREVIOUS. STILL THINK THE NAM IS TOO ROBUST WITH LLEVEL
MOISTURE...BUT EVEN THE FAR MORE CONSERVATIVE RAP ALLOWS FOR 500-750
JOULES OF MUCAPE DEVELOPMENT OVER THE HIGH TERRAIN OF INTERIOR
NORTHERN LOWER. QG FORCING FOR ASCENT IS NIL OVERHEAD WITH SLOWLY
BUILDING HEIGHTS ALOFT REQUIRING LAKE BREEZES/UPSLOPE CONVERGENCE TO
PUSH US TO CONVECTIVE INITIATION. HAVE TROUBLE BELIEVING WE CAN GET
AROUND MODEST CAPPING NEAR H7 PURELY WITH BOUNDARY LAYER PROCESSES.
THUS...WILL MAINTAIN GOING DRY FORECAST FOR THE AFTERNOON HOURS.
QPF: BASIN WIDE AMOUNTS VERY LIGHT...LESS THAN 0.05". ISOLATED
LOCATIONS COULD RECEIVE NEAR 0.20" GIVEN MODEST PWATS/WARM CLOUD
DEPTHS AND LIGHT STEERING FLOW.
TEMPERATURES: T8S NEAR +12C AT 00Z WITH CONTINUED SLOW WARMING
THROUGH TODAY SUGGESTS WE SHOULD BE ABLE TO BEST YESTERDAYS HIGHS
AND GUIDANCE CONSENSUS HANDLES THIS WELL...WITH MID/UPPER 70S INLAND
AND CLOSER TO 70 AT THE LAKE-BREEZE COOLED COASTS.
WINDS: CONTINUED LIGHT GRADIENT FAVORS ROBUST LAKE BREEZE
DEVELOPMENT THIS AFTERNOON.
TONIGHT...
PRECIPITATION CHANCES: WITH NO HELPFUL LLEVEL MOISTURE
ADVECTION...CHANCES WILL BE CONTINGENT ON AFTERNOON ACTIVITY
PERSISTING INTO THE EVENING. GIVEN THE CURRENT EXPECTATION THAT
WE/LL REMAIN SHOWER FREE THROUGH THE AFTERNOON...WILL MAINTAIN DRY
CONDITIONS THROUGH THE TONIGHT PERIOD AS WELL.
QPF: NIL.
TEMPERATURES: WILL STICK NEAR GUIDANCE CONSENSUS IN THE MID 50S AS
PARTLY CLOUDY SKIES SHOULD ALLOW FOR MODEST RADIATIONAL COOLING WITH
GEOSTROPHIC FLOW AT 1000MB NEAR 10KTS LIKELY STILL ALLOW MOST
LOCATIONS TO DECOUPLE.
WINDS: CALM OR LIGHT DRAINAGE FLOWS EXPECTED.
FOG: WITH MID/UPPER LEVEL MOISTURE BEGINNING TO PULL EAST...CAN SEE
SOME INCREASED FOG POTENTIAL AS LLEVEL FLOW GAINS A SOUTHWESTERLY
COMPONENT WITH CONTINUED WEAK LLEVEL MOISTURE ADVECTION AND ENOUGH
CLEARING FOR RADIATIONAL COOLING IN THE PRESENCE OF ELEVATED 2M
DEWPOINTS. WILL ADD PATCHY FOG TO THE FORECAST AFTER MIDNIGHT.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 314 AM EDT SUN JUN 22 2014
...SCATTERED THUNDERSTORMS MONDAY AND MONDAY NIGHT...
IMPACTS: MINIMAL. SEVERE STORMS STILL LOOK UNLIKELY.
SYNOPTIC PATTERN/EVOLUTION:
THE ENTIRE FORECAST PERIOD OF MONDAY THROUGH THE NEXT WEEKEND WILL
SEE A SHALLOW AND PROGRESSIVE MID LEVEL AMPLITUDE PATTERN THROUGH A
GOOD CHUNK OF THE WORK WEEK. THEN...HEIGHTS RISE OVER THE HEART OF
THE COUNTRY...INCLUDING THE WESTERN GREAT LAKES. THIS IS IN RESPONSE
TO TWO LARGE UPPER/CLOSED LOWS DROPPING INTO THE PAC NW/NEW ENGLAND.
AN INCREASINGLY MUGGIER AIR MASS MONDAY AND EARLY TUESDAY...AHEAD OF
AN APPROACHING AREA OF LOW PRESSURE AND PRECIPITATION...WILL GET
COOLED AND DRIED DOWN LATER TUESDAY THROUGH WEDNESDAY. TEMPERATURES
WILL START RISING BACK UP AGAIN FOR LATE IN THE WORK WEEK.
PRECIPITATION CHANCES AFTER EARLY TUESDAY DO NOT LOOK ALL THAT
FANTASTIC.
MON-TUES:
THE BEST ACTION RESIDES IN THIS TIME FRAME. SHALLOW RIDGING EXITS
EAST...WHILE AN ELONGATED UPPER TROUGH AXIS ACROSS ONTARIO BACKS
WINDS ALOFT WSW. SHORTWAVE ENERGY AND AN ASSOCIATED SFC LOW WILL
LIFT UP ACROSS NRN MICHIGAN. THIS LOW PRESSURE DOESN`T LOOK ALL THAT
IMPRESSIVE...BUT A WARM FRONT WILL EDGE UP THROUGH MUCH OF NRN
LOWER...WITH THE TRAILING COLD FRONT EXITING NEAR TUESDAY MORNING.
AS THE SFC LOW DEPARTS...ANOTHER COLD FRONT...ONE WITH MORE
REFRESHING AIR...WILL SLIDE SOUTHWARD THROUGH NRN MICHIGAN BY OVER
NIGHT TUESDAY NIGHT (UNCERTAINTY ON EXACT TIMING). COULD SEE SOME
SHOWERS POSSIBLY SNEAKING INTO A FEW SECTIONS OF NW LOWER MONDAY
MORNING...AND ALSO SOME POTENTIAL CONVECTIVE DEBRIS FROM FURTHER
WEST...BUT THE USING AN EXPECTED AVERAGE PARCEL OF 80/61 (DEW
POINT IS SOME QUESTION)...CAN POSSIBLY GLEAN 1000-1300 J/KG MONDAY
LATE AFTERNOON. RIGHT WITH THE WARM FRONTAL ARRIVAL. THE LOW TRACKS
OVER NRN MICHIGAN WITH MAINLY NRN LOWER SNEAKING INTO THE WARM
SECTOR FOR THE EVENING (TIMING ALSO IN SOME QUESTION). SHOWER AND
STORM CHANCES WILL BE GREATEST MONDAY NIGHT...AND ALTHOUGH NOTHING
OVERLY IMPRESSIVE...WILL HAVE TO WATCH THE DEVELOPMENTS SURROUNDING
WIND FIELDS AND INSTABILITY. THERE IS A TIGHTENING IN THE MID LEVEL
FLOW (40KTS)...AND IF THE INSTABILITY ABOVE CAN BE HAD...AND BEING
IN THE WARM SECTOR...WHILE EASTERN UPPER GETS GARDEN VARIETY SHOWERS
AND A FEW STORMS...NRN LOWER COULD SEE STRONGER CELLS. CELLS THAT
WILL BE IN A BETTER ENVIRONMENT FOR GUSTY WINDS/SMALLISH HAIL AND
THE POSSIBILITY OF A ROGUE TORNADO. THAT`S AN AWFUL LOT OF IF`S
THOUGH. AFTER THE LOW DEPARTS...AND SECONDARY COOL FRONT GETS
DROPPED THROUGH US...WITH MINIMAL FORCING...DIMINISHING MOISTURE AND
A TOTAL LACK OF INSTABILITY DUE TO MORE OF A COL AREA IN STORE FOR
US. HIGHS WELL INTO THE 70S MONDAY WILL START COOLING OFF...WITH
HIGHS TUESDAY IN THE UPPER 60S/70F IN EASTERN UPPER...AND UPPER 70S
NEARER SAGINAW BAY.
WEDNESDAY THROUGH NEXT WEEKEND:
AN EVEN COOLER DAY WEDNESDAY WITH HIGHS IN THE MAINLY IN THE 60S...A
FEW LOWER 70S...AS HIGH PRESSURE SLIPS INTO OUR NECK OF THE WOODS
FROM ONTARIO. SHOULD BE A BEAUTIFUL DAY. THERE ARE DEFINITE HINTS AT
SOME SHORTWAVE ACTIVITY TRACKING THROUGH US THURSDAY/THURSDAY NIGHT
FOR RAIN SHOWER CHANCES...BEFORE MID LEVEL HEIGHTS RISES BEGIN
FRIDAY AND CONTINUE INTO THE WEEKEND FOR A RETURN TO MIDDLE 70S TO
LOWER 80S TEMPS. EARLY HINTS ARE FOR NO PRECIPITATION NEXT WEEKEND
WITH ALL THE HEAT AND INSTABILITY RESIDING TO OUR WEST AND SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 106 AM EDT SUN JUN 22 2014
SUMMARY: A PLUME OF MID LEVEL MOISTURE WILL REMAIN ANCHORED ACROSS
NORTHERN MICHIGAN FOR MUCH OF THE UPCOMING TAF PERIOD WITH A FEW
SHOWERS FOR THE MORNING ON SUNDAY. THIS MOISTURE PLUME WILL LIFT
NORTH AND EAST OF THE REGION SUNDAY NIGHT WITH SOME POTENTIAL FOR
OVERNIGHT FOG DEVELOPMENT.
RESTRICTIONS: ONLY THREAT FOR RESTRICTIONS THROUGH THE PERIOD WILL
COME THROUGH DAYBREAK AT MBL/TVC. PRETTY MUCH A PERSISTENCE
FORECAST FROM ONE DAY AGO AT MBL/TVC WITH SOME DETERIORATION LIKELY
THROUGH DAYBREAK. THIS WILL LIKELY BRING A FEW PERIODS OF IFR CIGS
/AND POTENTIALLY VSBYS/ TO MBL...WITH OCCASIONAL MVFR CIGS /AND
POTENTIALLY VSBYS/ AT TVC.
ELSEWHERE...BKN VFR CLOUDINESS AND ISOLATED SHRAS WILL CONTINUE
BEFORE THINNING CLOUD COVER THIS EVENING. A FAVORABLE FOG SETUP
LOOKS POSSIBLE SUNDAY NIGHT...BUT EXPECT ANY SIGNIFICANT
RESTRICTIONS TO HOLD OFF UNTIL AFTER 06Z MONDAY.
WINDS: LIGHT WINDS TO CONTINUE THROUGH THE EARLY MORNING HOURS
BEFORE GIVING WAY TO LOCAL LAKE BREEZES IN THE AFTERNOON. WINDS WILL
AGAIN DIMINISH TO CALM/LIGHT DRAINAGE WINDS THIS EVENING.
LLWS: NO THREATS THIS CYCLE.
&&
.MARINE...
ISSUED AT 314 AM EDT SUN JUN 22 2014
SUMMARY: HIGH PRESSURE OVER HUDSON BAY WILL MOVE SOUTH AND EAST OFF
THE ATLANTIC COAST THROUGH MONDAY ALLOWING AN AREA OF LOW PRESSURE
TO MOVE INTO THE GREAT LAKES REGION FOR MONDAY NIGHT AND TUESDAY.
HIGH PRESSURE BUILDS INTO THE REGION BEHIND THIS LOW FOR WEDNESDAY
AND THURSDAY.
HEADLINES: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS
THROUGH MONDAY NIGHT. THERE IS SOME POTENTIAL FOR SMALL CRAFT LEVEL
WINDS UNDER NORTHWEST WINDS TUESDAY/TUESDAY NIGHT AS LOW PRESSURE
DEPARTS THE REGION TO THE EAST. AS LOW PRESSURE PULLS EAST OF THE
REGION HIGH PRESSURE BUILDS IN FOR THE WEDNESDAY-FRIDAY TIMEFRAME
WITH HEADLINE FREE CONDITIONS EXPECTED.
THUNDERSTORMS: CHANCES FOR STORMS INCREASE ON MONDAY WITH A PERIOD
OF THUNDERSTORMS LIKELY TUESDAY/TUESDAY NIGHT. WIDESPREAD SEVERE
THREAT IS LOW...BUT ISOLATED STRONG TO SEVERE STORMS ARE POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...SMD
SHORT TERM...ARNOTT
LONG TERM...SMD
AVIATION...ARNOTT
MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
400 AM CDT Sun Jun 22 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 336 AM CDT Sun Jun 22 2014
Once again the main forecast issue is thunderstorm chances. The
only ongoing precipitation early this morning is a shrinking area
of showers in Pike Co MO. This originated from a NW-SE cluster of
thunderstorms which occured just north of Mexico in response to
lift via a weak westerly LLJ along the cool side of a large scale
outflow boundary. That boundary remains somewhat identifiable
from far southern IL into central/NW MO. While there is no clear
cut model solution, there are suggestions by the deterministic
guidance which are supported by recent runs of the HRRR and the
4km NSSL WRF that this confluent zone from central through
southeast MO will be the region of scattered thunderstorm
development beginning near midday, with activity shifting east thru
the afternoon. There may be a region of somewhat greater coverage
and organization across northeast Missouri and west central IL
resulting from an eastward migrating vort max which is now present
in the central Plains. Highs once again look seasonable in the
upper 80s to lower 90s.
Glass
.LONG TERM: (Tonight through Saturday)
Issued at 336 AM CDT Sun Jun 22 2014
The greatest threat of thunderstorms tonight should also reside
across the northern portion of the CWA where the consensus of the
model QPFs have the highest coverage. This appears reasonable as a cold
front will be pushing into IA and NW MO in association with a much
better defined slowly progressive short wave trof and attendant
vort maxes. Strengthening and veering wind fields and a stronger
veering WSW LLJ should result in good eastward progression of
organized convection. The cold front will move slowly across the
area Monday and Monday night and should be accompanied by fairly
widespread showers and thunderstorms. The models vary on how far
south the front will push on Tuesday with the NAM showing the
least progression only into southern IL and southern MO while the
GFS and SREF push the front into AR. Eventually the front will
retreat back northward and be the focus for additional showers and
thunderstorms through the later half of the upcoming week. The NAM
is just about 12-24h faster thru its 84h forecast ending Wednesday.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1031 PM CDT Sat Jun 21 2014
Most of the convection across the area should dissipate by 06z
Sunday with only high level convective debris cloudiness remaining
late tonight which should thin out. There may be some fog late
tonight/early Sunday morning due to the recent rainfall and as the
surface wind becomes light. Diurnal cumulus clouds will develop
again late Sunday morning and afternoon with at least widely
scattered showers/storms expected Sunday afternoon into the
evening. Surface winds should be mainly s-swly on Sunday, then
weaken Sunday evening.
Specifics for KSTL: Lingering thundershowers should dissipate or
shift southeast of STL by 06z Sunday. After this mainly just
thinning high level convective debris clouds late tonight along
with the surface wind becoming light. Diurnal cumulus clouds will
develop again late Sunday morning and afternoon with at least
widely scattered showers/storms Sunday afternoon into the evening.
Light surface wind will become s-swly Sunday afternoon, then
weaken again Sunday evening.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1202 AM CDT Sun Jun 22 2014
.UPDATE:
Issued at 1159 PM CDT Sat Jun 21 2014
While remnants of evening storms dissipate fairly rapidly from
southeast Missouri into southwest Illinois, spotty convection
continues to linger north of COU. Given the somewhat persistent
and stubborn nature of this activity, am beginning to wonder if
some low chance of storms wont persist throughout the night over
our western areas, as very weak WAA of resdiually unstable air overruns
the rain-cooled airmass, and produces just enough lift to generate
spotty convection. Lastest RUC forecasts are certainly suggesting
this, with even the 12z NCEP 4km at least hinting in this
direction. So, update will be issued shortly which continues low
PoPs from central into ne MO and west central IL during the
overnight hours.
Truett
&&
.SHORT TERM: (Through Late Tonight)
Issued at 322 PM CDT Sat Jun 21 2014
Thunderstorm trends remain the primary focus of the short term
forecast. Expecting storms up over northeast MO and west central IL
to become more widespread through boundary interactions and
collisions. Airmass is very unstable with SBCAPE in excess of 4500
J/kg and SB-LIs of -9 to -10 all the way back into central and east
central MO. Expect that outflows from the storms up north will
propagate southward which will provide triggers for further
development. Storms could form into clusters or perhaps even a
broken line before dissipating this evening, most likely somewhere
near or just south of the Missouri River. There may be some patchy
fog late tonight in any areas that receive rain this evening, but
have left mention out for now due to the potentially patchy nature
of the rain. Temperatures tonight should be similar to what we
experienced last night so used a blend of guidance and persistence
for lows tonight.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 322 PM CDT Sat Jun 21 2014
The current pattern we are in will continue relatively unaltered
through late Thursday, with a flat west-east mid-level flow and
periodic effects from upper level disturbances or MCVs. This
alludes to a continuation of our unsettled wx and TSRA chances thru
much of this period, only being limited when available moisture
becomes a factor, or enhanced when a clear focus can be seen.
Rich atmospheric moisture will continue in place over our region
into Monday night, with PWs in excess of 1.5", tailing off a bit on
Tuesday and Wednesday, and returning for Thursday.
With that in mind, a similar setup will be found Sunday that we have
had the past few days for most locations, with weak boundaries, very
weak CINH and hi instability during the peak heating times, which
then fade with sunset. Some enhanced PoPs were maintained in
northeast MO for late afternoon with influences from the southern
periphery of the MCV du jour which is expected to be centered in IA
at that time, but by and large, the convection looks to be pretty
random, forming where enough local convergence can occur to initiate
and will be hard to detect until we get closer.
Better chances for SHRA/TSRA are expected on Monday and Monday night
with a more significant shortwave TROF that will pass into this
convectively favorable atmosphere--and went likely PoPs as a result.
Tuesday and Wednesday, at this time, look to be a couple of dry days
for most areas, but an intrusion from a strong enough upper level
disturbance would change that.
Rain chances return for a widespread area on Thursday with the
return of rich and deep moisture and another upper level shortwave.
A deep and amplified upper TROF is then expected to dig into the
western CONUS for the end of the week. The models diverge on what
this means for our area, but they do agree on rising heights and
upper ridging returning, but aren`t as sure on if that will be
accompanied by upper level disturbances or not. At this point, felt
prudent to fall back to climo PoPs in most places given the model
impasse.
Temps will remain relatively unchanged the next seven days with
temps at or a bit above normal, with Monday looking like the only
day where some areas may see below normal temps depending on how
fast the clouds and rain move in.
TES
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1031 PM CDT Sat Jun 21 2014
Most of the convection across the area should dissipate by 06z
Sunday with only high level convective debris cloudiness remaining
late tonight which should thin out. There may be some fog late
tonight/early Sunday morning due to the recent rainfall and as the
surface wind becomes light. Diurnal cumulus clouds will develop
again late Sunday morning and afternoon with at least widely
scattered showers/storms expected Sunday afternoon into the
evening. Surface winds should be mainly s-swly on Sunday, then
weaken Sunday evening.
Specifics for KSTL: Lingering thundershowers should dissipate or
shift southeast of STL by 06z Sunday. After this mainly just
thinning high level convective debris clouds late tonight along
with the surface wind becoming light. Diurnal cumulus clouds will
develop again late Sunday morning and afternoon with at least
widely scattered showers/storms Sunday afternoon into the evening.
Light surface wind will become s-swly Sunday afternoon, then
weaken again Sunday evening.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1147 PM CDT Sat Jun 21 2014
.DISCUSSION...
Issued at 359 PM CDT SAT JUN 21 2014
What else would one expect for the official first day of summer
other than an uncapped tropical airmass defined by high CAPEs and
weak shear with isolated convection along weak boundaries. Very weak
and isolated convection continues to sputter across northern MO this
afternoon in a region of weak h8 convergence. Increasing convection
is noted in a region of moderate h8 moisture convergence which
extends southwest from west central IL cluster into the east central
CWA. HRRR has been picking out this general area for most of today.
Will focus higher PoPs for the late afternoon and early evening
hours this area. A small MCV over south central NE left over from
earlier convection is drifting east towards slightly higher MLCAPEs
around 2000 J/kg. Will insert low chance PoPs for this evening for
nw and north central MO for possible convective development. Last
several runs of the HRRR generates scattered convection this area.
Expect another complex convective scenario tonight. Current
convection over the NE Panhandle may eventually merge with another
nocturnal MCS that rolls off the CO Front Range and heads east. Will
throw in some PoPs over northwest MO towards Sunday morning to cover
the possibility of a dying MCS reaching the CWA.
Continued very warm and humid on Sunday with above average
temperatures. Low confidence on placement of PoPs as any outflow
boundaries left over from tonight`s convection will play a key role.
Sunday night into Monday still holds the highest PoPs during this
forecast period. While the models have started to diverge on where
another nocturnal MCS will track there is good consensus that a cold
front moving southeast through NE/IA/KS will play a pivotal role.
Have had to lower qpf during this period as confidence on a large
MCS moving through the CWA has diminished. But should see good
coverage of convection with the front. High precipitable water
values are a concern should storms crawl through or back build along
the front. So, later forecasts may need to ramp qpf back up.
While Tuesday looks dry and a tad cooler behind the front weak
embedded disturbances within the quasi-zonal pattern will provide
a lot of uncertainty on timing and location of any convection for
Wednesday/Wednesday night.
The upper pattern evolves for the latter half of the week as an
upper trough pushes through the intermountain region. The backing
flow downstream will enable a southwesterly fetch to spread through
the Central Plains and Mid MO Valley. Should see a slight uptick in
temperatures and humidity with warmer air aloft spreading into the
CWA and forcing any convection to become elevated and more nocturnal.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1147 PM CDT SAT JUN 21 2014
VFR conditions are likely to occur for the entire forecast with
generally light southerly winds. Forecast soundings cotninue to show
a nearly to fully uncapped environment tomorrow afternoon with what
should be a multitude of remnant boundaries for storms to possibly
develop on. Have added a VCTS group for the afternoon given this
possibility. Of greater likelihood to impact the terminals is the
potential for more widespread storms to move through very late in the
forecast. There is a significant amount of uncertainty with the
timing of this ranging from around 00Z Monday to after 06Z Monday.
Given this, will just keep the VCTS group through the end of the
forecast as the potential from afternoon storms may evolve into the
potential for more widespread evening/overnight storms.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...MJ
AVIATION...CDB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
345 AM CDT SUN JUN 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUN 22 2014
OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY
RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST
MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING
IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE
TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE
HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO
BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT
NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE
AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 22 2014
MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE
EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD
RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING
THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR
DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED
FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS
THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS
THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT
UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY
RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT
PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK
SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT
WEEKEND.
FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED
FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK
UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR
A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE
HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS
IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE
HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON
TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA.
WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR
STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY
WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE
OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS
LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR
COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY
BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA
TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE
POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT
IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD
30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE
THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS
SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE
STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY
NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR
MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE
FROM THE PROCEDURE ATTM.
TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT
WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON
MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER
90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS
DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO
WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED
FORECAST PERIODS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1141 PM CDT SAT JUN 21 2014
THUNDERSTORMS ARE POSSIBLE IN THE VICINITY OF THE KLBF AND KVTN
TERMINALS THROUGH 09Z SUNDAY. THUNDERSTORMS WILL BE POSSIBLE ONCE
AGAIN SUNDAY AFTERNOON AT BOTH THE KLBF AND KVTN TERMINALS. VISBYS
MAY DROP AS LOW AS 3SM IN THE VICINITY OF THUNDERSTORMS WITH CIGS
AS LOW AS 5000 FT AGL. CIGS AWAY FROM THUNDERSTORMS WILL BE AROUND
10000 FT AGL...EXCEPT SUNDAY EVENING WHERE CIGS WILL DROP TO 2500
TO 5000 FT AGL BEHIND AN EXITING FRONT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
239 AM CDT SUN JUN 22 2014
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 234 AM CDT SUN JUN 22 2014
MOSAIC RADAR IMAGERY THIS MORNING SHOWING TWO DISTINCT CLUSTER OF
TSTMS...ONE OVER ERN SD ASSOCIATED WITH A SEWD BOUND COLD FRONT/MID
LYR UPGLIDE. OTHER ONE WAS SITUATED ALONG INVERTED SFC TROF/THERMAL
BNDRY EXTENDING FROM NW KS INTO S-CNTRL NEB WITHIN AREA OF MID LYR
QG FORCING. THE LATEST HRRR IS ADVERTISING THE NRN ACTIVITY WILL
QUICKLY DIMINISH THE NEXT COUPLE HOURS WHILE SW TSTMS BECOME
DOMINATE FEATURE AND EXPAND INTO THE CWA EARLY THIS MORNING. FOR
TODAY/TONIGHT...EXPECT COMBINATION OF DAYTIME HEATING AND MOISTURE RICH
ENVIRONMENT EXPECT WILL ALLOW FOR QUICK DESTABILIZATION AND TSTM
REDEVELOPMENT ALONG AXIS OF BNDRY LYR THETA-E CONVG WITH APPROACH
OF FRONTAL BNDRY FROM THE NORTH. AS FOR SEVERE TSTM
POTENTIAL...BOTH NAM AND GFS ARE IN PRETTY GOOD AGREEMENT SHOWING
HIGH BUOYANCY BUT RELATIVELY WEAK VERTICAL WIND SHEAR THUS
FAVORING MULTISTORM DEVELOPMENT. NEVERTHELESS...CANNOT TOTALLY
DISCOUNT A FEW SEVERE STORMS LATE AFTN/EARLY EVENING. PCPN
ACTIVITY WILL BE COMING TO AN END THEN MONDAY MORNING AS DRY
AIRMASS/SUBSIDENCE BUILDS IN FROM THE NORTH. TUES/TUES
NIGHT...MODELS LAY QPF WEST OF THE CWA WITHIN AREA OF PRONOUNCED
MID LYR AGEOSTROPHIC LIFT. PCPN ACTIVITY THEN PROGGED TO EXPAND
QUICKLY EWD INTO THE CWA...THUS WILL LEAVE GOING POPS IN PLACE.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 234 AM CDT SUN JUN 22 2014
GOING FCST HAS PCPN CHANCES PRETTY MUCH IN PLACE THRU THE EXTENDED
PDS. AT THIS POINT GIVEN LATEST MODELS SUPPORT GOING POPS...SEE
LITTLE REASON FOR MAKING ANY MAJOR MODIFICATIONS. ZONAL FLOW EARLY
ON IN THE FCST PD BECOMES MORE AMPLIFIED IN RESPONSE TO A DEEP
UPSTREAM UPPER TROF MOVING ONTO THE WEST COAST THURSDAY BEFORE LARGE
SCALE BEGINS SMOOTHING OUT TO NEAR ZONAL NEXT WEEKEND. PCPN CHANCE
PRETTY MUCH REVOLVING AROUND LIFTING WARM FRONT FOLLOWED BY A COLD
FRONT ADVANCING THRU THE CNTRL PLAINS. THERMAL ADVECTION WITH THESE
BOUNDARIES LOOKS RELATIVELY WEAK SO NOT MUCH DEVIATION FROM NEAR
NORMAL TEMPS ANTICIPATED.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1146 PM CDT SAT JUN 21 2014
VFR CONDITIONS ARE EXPECTED FOR THE MOST PART. SCATTERED SHOWERS
AND THUNDERSTORMS MAY DEVELOP ACROSS ALL OF EASTERN NEBRASKA BUT
CONFIDENCE IS LOW ON TIMING AND COVERAGE OF THE THUNDERSTORMS.
CHANCES WILL CONTINUE INTO SUNDAY AFTERNOON AND EVENING AHEAD OF A
COLD FRONT. WINDS WILL TURN TO THE NORTH AT KOFK AROUND 00Z/MON.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
147 AM EDT SUN JUN 22 2014
.SYNOPSIS...
OTHER THAN A FEW CLOUDS...HIGH PRESSURE WILL BRING FAIR WEATHER AND
SEASONABLE TEMPERATURES TO THE REGION THROUGH MONDAY. INCREASING
WARMTH AND HUMIDITY WILL BRIEFLY RETURN BY THE MIDDLE OF NEXT WEEK
ALONG WITH THE CHANCE OF SHOWERS AND A FEW THUNDERTORMS.
THEREAFTER...AN EXTENDED STRETCH OF FAIR AND DRY WEATHER RETURNS
FOR LATER NEXT WEEK INTO NEXT WEEKEND AS HIGH PRESSURE BUILDS
ACROSS THE NORTHEAST.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1252 AM EDT SUNDAY...STILL CONTENDING WITH VARIABLE MID-
LEVEL CLOUDINESS ACROSS NORTHERN NEW YORK INTO NORTHERN/CENTRAL
VERMONT AT THIS HOUR. 03Z RAP ANALYSES APPEAR TO HAVE THE BEST
HANDLE ON THE LAYER OF CLOUDINESS...MANIFESTING AS HIGHER RH IN
THE 850-700 MB LAYER. THOUGH THE RAP WANTS TO KEEP THIS MOISTURE
AXIS AROUND THROUGH OVERNIGHT CURRENT SATELLITE TRENDS SUGGEST
THAT THE CLOUDS WILL BURN OFF SOONER THAN THAT. I`VE HAD TO ADJUST
SKY COVER TO KEEP AT LEAST PARTLY CLOUDY SKIES AROUND BUT
EVENTUALLY CLEARING OUT BY THE PRE-DAWN HOURS. THINK THAT AREAS OF
RIVER VALLEY FOG ARE STILL POSSIBLE BASED ON NARROW T-TD
SPREADS...BUT MAY NOT DEVELOP UNTIL MORE CLEARING CAN TAKE PLACE
TOWARDS MORNING. ONLY OTHER CHANGE WAS TO ADJUST MINS BY A DEGREE
OR TWO. LOWS TO RANGE FROM THE UPPER 30S/LOW 40S NORTHEAST KINGDOM
AND ADIRONDACKS TO THE LOW 50S IN THE CHAMPLAIN AND SAINT LAWRENCE
VALLEYS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 308 PM EDT SATURDAY...IDEAL EARLY SUMMER WEATHER CONTINUES
SUNDAY INTO MONDAY WITH SURFACE HIGH PRESSURE REMAINING IN CONTROL
ALONG WITH BUILDING MID-LEVEL HEIGHTS ABOVE 850 MB. OUTSIDE A FEW
PASSING HIGH CLOUDS AND/OR DIURNALLY-DRIVEN FAIR WEATHER
CUMULUS...PLENTY OF SUNSHINE EXPECTED ALONG WITH CHANCES OF
PRECIPITATION ESSENTIALLY NIL. BLENDED 18-00Z MODEL-AVERAGED 925MB
THERMAL PROGS SUGGEST HIGHS SOLIDLY INTO THE 70S TOMORROW...AND
UPPER 70S TO LOWER 80S BY MONDAY AS LIGHT SOUTHERLY RETURN FLOW
COMMENCES. HUMIDITY VALUES TO REMAIN QUITE MODEST HOWEVER SO
DESPITE THE INCREASE IN WARMTH ON MONDAY SENSIBLE CONDITIONS
SHOULD STILL RELATIVELY PLEASANT.
BY MONDAY NIGHT A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARE
EXPECTED AS MOISTURE GRADUALLY INCREASES AHEAD OF A SHORTWAVE TROUGH
ADVANCING EASTWARD FROM THE GREAT LAKES AND SOUTHERN CANADA. CAN`T
COMPLETELY RULE OUT A STRAY SHOWER OR STORM TOWARD SUNRISE TUESDAY
ACROSS OUR SLV COUNTIES IN CLOSER PROXIMITY TO THE LEAD PRE-FRONTAL
TROUGH...BUT THE MAJORITY OF THE NIGHT WILL BE PRECIPITATION-FREE.
WITH DEEPENING SOUTHERLY FLOW AND WARM THERMAL ADVECTIVE PROCESSES
OVERNIGHT LOWS WILL BE CONSIDERABLY MILDER...LIKELY HOLDING IN THE
60S ACROSS THE CHAMPLAIN AND ST LAWRENCE VALLEYS...AND 50S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 335 PM EDT SATURDAY...LONG TERM FCST CHALLENGE WL BE TIMING
OF SFC BOUNDARY AND ASSOCIATED MOISTURE AND CHCS FOR
SHOWERS/STORMS ON TUES INTO WEDS. LATEST 12Z GUIDANCE HAS
INCREASED THE TIMING OF THIS FEATURE BY 4 TO 8 HRS...RESULTING IN
THE HIGHEST POPS OCCURRING LATE TUES AFTN WESTERN CWA AND
OVERNIGHT TUES INTO WEDS ACRS THE REST OF THE FA. THE ECMWF CONTS
TO BE THE SLOWEST AND WL FOLLOW GIVEN RECENT VERIFICATION. BREEZY
SOUTHERLY FLW WL HELP ADVECT INCREASED INSTABILITY AND MOISTURE
INTO OUR CWA ON TUESDAY. PWS VALUES REACH BTWN 1.75 AND
2.0"...WHILE SFC DWPTS SURGE INTO THE 60S...CREATING CAPE READINGS
BTWN 800 AND 1200 J/KG ON TUES AFTN. ALSO...NOTED ON SOUNDINGS
ESPECIALLY ACRS THE SLV NEAR KMSS THE LLVL WIND PROFILES INCREASE
BTWN 30 AND 40 KNOTS AT 85H...SUPPORTING SOME FAVORABLE SHEAR
PARAMETERS. GIVEN THE MARGINAL INSTABILITY...THINKING A FAST
MOVING LINE OF CONVECTION WL BE POSSIBLE WITH BRIEF HEAVY
RAINFALL...GUSTY WINDS...AND SMALL HAIL...ESPECIALLY SLV/DACKS ON
TUES AFTN/EVENING. THIS ACTIVITY WL PROBABLY DECREASE IN AREAL
COVERAGE/INTENSITY AS IT MOVES EAST INTO VT...WHERE INSTABILITY
FROM THE LOSS OF SFC HEATING WL BE LIMITED. CRNT HWO HAS MENTION
OF SMALL HAIL/GUSTY WINDS WHICH LOOKS REASONABLE GIVEN MARGINAL
INSTABILITY ON TUES. WL MENTION HIGHEST LIKELY POPS LATE TUES INTO
EARLY WEDS MORNING. OTHERWISE...SFC BOUNDARY CLRS OUR CWA BY 18Z
WEDS...WITH BEST MOISTURE AND INSTABILITY LOCATED ACRS THE MID
ATLANTIC/SNE REGION. WL MENTION LIKELY POPS WITH SCHC FOR THUNDER
ON WEDS MORNING. FOR LATE WEEK INTO NEXT WEEKEND...STILL SOME
UNCERTAINTY ON REDEVELOPMENT OF DEEP TROF ACRS THE NE CONUS AND
DRY NW FLW ALOFT. LATEST 12Z ECMWF SHOWS POTENT 5H VORT CROSSING
OUR CWA LATE THURS NIGHT INTO FRIDAY...BUT MOISTURE IS
LIMITED...SO PROBABLY ONLY AN INCREASE IN CLOUDS. BETTER FRNT AND
SOME MID LVL MOISTURE CROSSES OUR REGION LATE SAT INTO SUNDAY OF
NEXT WEEK...WITH ADDITIONAL CHC FOR SHOWERS. OVERALL...TEMPS START
OUT ABOVE NORMAL ON TUES/WEDS AND TREND BACK SLIGHTLY BLW NORMAL
BY LATE WEEK...WITH MAINLY DRY CONDITIONS DEVELOPING AFT WEDS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 12Z MONDAY...VFR CONDITONS EXPECTED FOR THE MAJORITY OF
THE PERIOD. ONLY EXCEPTIONS WILL BE SOME PATCHY FOG/BR AT MPV/SLK
08-12Z. OTHERWISE DRY AND SKC-SCT060. WINDS LIGHT AND VARIABLE
DURING THE PRE-DAWN HRS...BECOMING NW AROUND 5 KTS AFTER 14Z...AND
LIGHT AND VARIABLE AGAIN TONIGHT.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...SURFACE HIGH OVER THE GULF
OF MAINE WILL MAINTAIN GENERALLY VFR CONDITIONS MONDAY AND MONDAY
NIGHT WITH LIGHT S-SW WINDS. INCREASING HEAT AND HUMIDITY WILL
BRING A CHANCE FOR THUNDERSTORMS TUESDAY AFTN/EVE...MAINLY AT THE
NY TAF SITES. BRIEF PERIODS OF IFR CONDITIONS AND GUSTY WINDS CAN
BE EXPECTED WITH ANY TSTMS THAT FORM LATE TUESDAY. SHOWERS AND
ISOLD THUNDERSTORMS REMAIN POSSIBLE TUESDAY NIGHT INTO
WEDNESDAY AS A WEAK COLD FRONT SHIFTS EWD THROUGH THE REGION...FOLLOWED
BY CLEARING/MAINLY VFR WEDNESDAY NIGHT AND THURSDAY BEHIND THE FRONT.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...WGH/LOCONTO
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...BANACOS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1252 AM EDT SUN JUN 22 2014
.SYNOPSIS...
OTHER THAN A FEW CLOUDS...HIGH PRESSURE WILL BRING FAIR WEATHER AND
SEASONABLE TEMPERATURES TO THE REGION THROUGH MONDAY. INCREASING
WARMTH AND HUMIDITY WILL BRIEFLY RETURN BY THE MIDDLE OF NEXT WEEK
ALONG WITH THE CHANCE OF SHOWERS AND A FEW THUNDERTORMS.
THEREAFTER...AN EXTENDED STRETCH OF FAIR AND DRY WEATHER RETURNS
FOR LATER NEXT WEEK INTO NEXT WEEKEND AS HIGH PRESSURE BUILDS
ACROSS THE NORTHEAST.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1252 AM EDT SUNDAY...STILL CONTENDING WITH VARIABLE MID-
LEVEL CLOUDINESS ACROSS NORTHERN NEW YORK INTO NORTHERN/CENTRAL
VERMONT AT THIS HOUR. 03Z RAP ANALYSES APPEAR TO HAVE THE BEST
HANDLE ON THE LAYER OF CLOUDINESS...MANIFESTING AS HIGHER RH IN
THE 850-700 MB LAYER. THOUGH THE RAP WANTS TO KEEP THIS MOISTURE
AXIS AROUND THROUGH OVERNIGHT CURRENT SATELLITE TRENDS SUGGEST
THAT THE CLOUDS WILL BURN OFF SOONER THAN THAT. I`VE HAD TO ADJUST
SKY COVER TO KEEP AT LEAST PARTLY CLOUDY SKIES AROUND BUT
EVENTUALLY CLEARING OUT BY THE PRE-DAWN HOURS. THINK THAT AREAS OF
RIVER VALLEY FOG ARE STILL POSSIBLE BASED ON NARROW T-TD
SPREADS...BUT MAY NOT DEVELOP UNTIL MORE CLEARING CAN TAKE PLACE
TOWARDS MORNING. ONLY OTHER CHANGE WAS TO ADJUST MINS BY A DEGREE
OR TWO. LOWS TO RANGE FROM THE UPPER 30S/LOW 40S NORTHEAST KINGDOM
AND ADIRONDACKS TO THE LOW 50S IN THE CHAMPLAIN AND SAINT LAWRENCE
VALLEYS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 308 PM EDT SATURDAY...IDEAL EARLY SUMMER WEATHER CONTINUES
SUNDAY INTO MONDAY WITH SURFACE HIGH PRESSURE REMAINING IN CONTROL
ALONG WITH BUILDING MID-LEVEL HEIGHTS ABOVE 850 MB. OUTSIDE A FEW
PASSING HIGH CLOUDS AND/OR DIURNALLY-DRIVEN FAIR WEATHER
CUMULUS...PLENTY OF SUNSHINE EXPECTED ALONG WITH CHANCES OF
PRECIPITATION ESSENTIALLY NIL. BLENDED 18-00Z MODEL-AVERAGED 925MB
THERMAL PROGS SUGGEST HIGHS SOLIDLY INTO THE 70S TOMORROW...AND
UPPER 70S TO LOWER 80S BY MONDAY AS LIGHT SOUTHERLY RETURN FLOW
COMMENCES. HUMIDITY VALUES TO REMAIN QUITE MODEST HOWEVER SO
DESPITE THE INCREASE IN WARMTH ON MONDAY SENSIBLE CONDITIONS
SHOULD STILL RELATIVELY PLEASANT.
BY MONDAY NIGHT A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARE
EXPECTED AS MOISTURE GRADUALLY INCREASES AHEAD OF A SHORTWAVE TROUGH
ADVANCING EASTWARD FROM THE GREAT LAKES AND SOUTHERN CANADA. CAN`T
COMPLETELY RULE OUT A STRAY SHOWER OR STORM TOWARD SUNRISE TUESDAY
ACROSS OUR SLV COUNTIES IN CLOSER PROXIMITY TO THE LEAD PRE-FRONTAL
TROUGH...BUT THE MAJORITY OF THE NIGHT WILL BE PRECIPITATION-FREE.
WITH DEEPENING SOUTHERLY FLOW AND WARM THERMAL ADVECTIVE PROCESSES
OVERNIGHT LOWS WILL BE CONSIDERABLY MILDER...LIKELY HOLDING IN THE
60S ACROSS THE CHAMPLAIN AND ST LAWRENCE VALLEYS...AND 50S ELSEWHERE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 335 PM EDT SATURDAY...LONG TERM FCST CHALLENGE WL BE TIMING
OF SFC BOUNDARY AND ASSOCIATED MOISTURE AND CHCS FOR
SHOWERS/STORMS ON TUES INTO WEDS. LATEST 12Z GUIDANCE HAS
INCREASED THE TIMING OF THIS FEATURE BY 4 TO 8 HRS...RESULTING IN
THE HIGHEST POPS OCCURRING LATE TUES AFTN WESTERN CWA AND
OVERNIGHT TUES INTO WEDS ACRS THE REST OF THE FA. THE ECMWF CONTS
TO BE THE SLOWEST AND WL FOLLOW GIVEN RECENT VERIFICATION. BREEZY
SOUTHERLY FLW WL HELP ADVECT INCREASED INSTABILITY AND MOISTURE
INTO OUR CWA ON TUESDAY. PWS VALUES REACH BTWN 1.75 AND
2.0"...WHILE SFC DWPTS SURGE INTO THE 60S...CREATING CAPE READINGS
BTWN 800 AND 1200 J/KG ON TUES AFTN. ALSO...NOTED ON SOUNDINGS
ESPECIALLY ACRS THE SLV NEAR KMSS THE LLVL WIND PROFILES INCREASE
BTWN 30 AND 40 KNOTS AT 85H...SUPPORTING SOME FAVORABLE SHEAR
PARAMETERS. GIVEN THE MARGINAL INSTABILITY...THINKING A FAST
MOVING LINE OF CONVECTION WL BE POSSIBLE WITH BRIEF HEAVY
RAINFALL...GUSTY WINDS...AND SMALL HAIL...ESPECIALLY SLV/DACKS ON
TUES AFTN/EVENING. THIS ACTIVITY WL PROBABLY DECREASE IN AREAL
COVERAGE/INTENSITY AS IT MOVES EAST INTO VT...WHERE INSTABILITY
FROM THE LOSS OF SFC HEATING WL BE LIMITED. CRNT HWO HAS MENTION
OF SMALL HAIL/GUSTY WINDS WHICH LOOKS REASONABLE GIVEN MARGINAL
INSTABILITY ON TUES. WL MENTION HIGHEST LIKELY POPS LATE TUES INTO
EARLY WEDS MORNING. OTHERWISE...SFC BOUNDARY CLRS OUR CWA BY 18Z
WEDS...WITH BEST MOISTURE AND INSTABILITY LOCATED ACRS THE MID
ATLANTIC/SNE REGION. WL MENTION LIKELY POPS WITH SCHC FOR THUNDER
ON WEDS MORNING. FOR LATE WEEK INTO NEXT WEEKEND...STILL SOME
UNCERTAINTY ON REDEVELOPMENT OF DEEP TROF ACRS THE NE CONUS AND
DRY NW FLW ALOFT. LATEST 12Z ECMWF SHOWS POTENT 5H VORT CROSSING
OUR CWA LATE THURS NIGHT INTO FRIDAY...BUT MOISTURE IS
LIMITED...SO PROBABLY ONLY AN INCREASE IN CLOUDS. BETTER FRNT AND
SOME MID LVL MOISTURE CROSSES OUR REGION LATE SAT INTO SUNDAY OF
NEXT WEEK...WITH ADDITIONAL CHC FOR SHOWERS. OVERALL...TEMPS START
OUT ABOVE NORMAL ON TUES/WEDS AND TREND BACK SLIGHTLY BLW NORMAL
BY LATE WEEK...WITH MAINLY DRY CONDITIONS DEVELOPING AFT WEDS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...VFR CONDITONS EXPECTED FOR THE MAJORITY OF
THE PERIOD. ONLY EXCEPTIONS WILL BE SOME PATCHY FOG/BR AT
MSS/MPV/SLK. SCATTERED CUMULUS CLOUDS FROM THIS AFTERNOON WILL
GRADUALLY DISSIPATE THIS EVENING WITH ONLY A FEW LINGERING
OVERNIGHT. THIS WILL LEAD TO MOSTLY CLEAR SKIES...WHICH COMBINED
WITH LIGHT WINDS AND STRONG RADIATIONAL COOLING...MAY LEAD TO THE
DEVELOPMENT OF SOME PATCHY FOG/BR. OVERALL CONDITIONS ARE SIMILAR
TO PREVIOUS NIGHT`S...SO TIMING OF FOG DEVELOPMENT SHOULD PLAY OUT
SIMILAR AS WELL. SOME MINOR DIFFERENCES NOTED ARE THE SLIGHTLY HIGHER
CROSS-OVER TEMPERATURES AT SLK/MSS AND SLIGHTLY WARMER FORECAST
LOWS AT MPV. THIS SHOULD LEAD TO SLK HAVING A SOMEWHAT GREATER THREAT
FOR IFR OR LOWER FOG. BEST CHANCES FOR FOG RUN 07Z-12Z.
AFTERWARD...ADDITIONAL CUMULUS CLOUDS DEVELOP ON SUNDAY BUT ALL
SITES WILL BE VFR. CAN`T RULE OUT A VERY LIGHT INSTABILITY RAIN
SHOWER AT SLK/MPV BUT WOULD BE VERY ISOLATED. WINDS LIGHT AND
LOCALLY VARIABLE TONIGHT REMAIN LIGHT AROUND 5 KNOTS ON
SUNDAY...GENERALLY OUT OF THE NORTH/NORTHEAST...EXCEPT EAST AT
PBG.
OUTLOOK 00Z MONDAY THROUGH THURSDAY...SFC HIGH PRES WL RESULT IN VFR
CONDITIONS CONTINUING FROM SUNDAY EVENING THRU 18Z TUES. THE
COMBINATION OF INCREASED INSTABILITY AND APPROACHING SFC BOUNDARY
WL HELP IN THE DEVELOPMENT OF SCATTERED SHOWERS/STORMS ON TUES
AFTN/EVENING. BRIEF PERIODS OF MVFR CIGS/VIS WL BE
POSSIBLE...ALONG WITH SOME GUSTY WINDS NEAR THUNDERSTORMS...WHICH
WL CREATE AREAS OF LOCALIZED TURBULANCE. ALSO...CHANNEL SOME WIND
GUSTS TO 30 MPH WL BE POSSIBLE ON TUES AFTN AT
MSS/BTV/PBG...ASSOCIATED WITH A DEVELOPING LLVL JET. VFR
CONDITIONS RETURN FOR WEDNESDAY AND THURSDAY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...WGH/LOCONTO
SHORT TERM...JMG
LONG TERM...TABER
AVIATION...TABER/MUCCILLI
AREA FORECAST DISCUSSION
NWS RALEIGH NC
310 AM EDT SUN JUN 22 2014
.SYNOPSIS...A SURFACE FRONT WILL PUSH SOUTHEAST THROUGH CENTRAL NORTH
CAROLINA THIS MORNING. WEAK HIGH PRESSURE WILL THEN EXTEND OVER THE AREA
THROUGH EARLY MONDAY. A SURFACE TROUGH OF LOW PRESSURE WILL RETURN
TUESDAY THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 310 AM SUNDAY...
A WEAK/WAVY FRONTAL ZONE IS DRAPED ACROSS THE CWA THIS
MORNING...THOUGH THE TRUE AIRMASS CHANCE REMAINS TO THE NORTH ACROSS
CENTRAL VA. ALOFT WATER VAPOR IMAGERY SHOWS VARIOUS SMALL
DISTURBANCES WITHIN BROAD CYCLONIC FLOW OVER THE EAST COAST. THE
FRONT WILL SINK SOUTH OVER SC TODAY AND EVENTUALLY DISSIPATE AS HIGH
PRESSURE OVER THE NORTHEAST NOSES INTO THE AREA. WITH THE PRIMARY
AXIS OF LOW-LEVEL CONVERGENCE SOUTH OF THE AREA TODAY AND LOWER PW
AIR FILTERING IN FROM THE NORTH...ESPECIALLY OVER THE CENTRAL AND
WESTERN PIEDMONT...POPS WILL BE MUCH LOWER THAN THE PAST COUPLE OF
DAYS. DEWPOINTS WILL REMAIN NEAR 70 OVER THE COASTAL PLAIN AND
MLCAPE MAY REACH 1000 J/KG. MOST GUIDANCE FOCUSES QPF OVER THE
COASTAL PLAIN AND THE SPC STORM SCALE ENSEMBLE SHOWS THE MOST
ACTIVITY ACROSS THE NORTHERN COASTAL PLAIN....WHERE SLIGHT CHANCE
POPS WILL BE FOCUSED. LOW-LEVEL THICKNESSES WILL BE DOWN ABOUT 10-
15M FROM YESTERDAY...THOUGH LOCATIONS IN THE NORTHEAST WILL FEEL THE
EFFECTS A LITTLE MORE...WITH HIGHS IN THE MID 80S NORTH TO LOWER 90S
SOUTH.
HIGH PRESSURE NOSES INTO THE AREA TONIGHT WITH THE POTENTIAL FOR
SOME STRATUS TO DEVELOP WITH A WEAK EAST-SOUTHEASTERLY LOW-LEVEL
FLOW. LOWS IN THE MID TO UPPER 60S.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 310 AM SUNDAY...
RIDGING ALOFT WILL BUILD OVER THE SOUTHEAST US ON MONDAY AS THE HIGH
EXTENDING INTO THE AREA FROM NEW ENGLAND BEGINS TO RETREAT. MODELS
ARE FAIRLY ACTIVE OVER WESTERN NC AS PW RETURNS TO ABOVE 1.5 INCHES.
THE WESTERN PIEDMONT WOULD BE THE FAVORED AREA FOR WIDELY SCATTERED
AFTERNOON STORMS GIVEN WEAK WESTERLY STEERING FLOW AND LACK OF
SIGNIFICANT FORCING. HIGHS AGAIN RIGHT AROUND NORMAL IN THE 86-90
RANGE. LOWS 66-70.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 310 AM SUNDAY...
RETURN FLOW WILL BE ONGOING WITH SUPPRESSIVE SHORT WAVE MID LEVEL
RIDGING SHIFTING EAST ON TUESDAY. THIS WILL LEAD TO INCREASED
CONVECTIVE COVERAGE...A LITTLE MORE SO IN THE WEST...TUESDAY
AFTERNOON AS HIGHS FLIRT WITHIN A DEGREE OR TWO OF 90. A SHORT WAVE
TROF AND ASSOCIATED SURFACE FRONT WILL BE MOVING ACROSS THE AREA
TUESDAY NIGHT/WEDNESDAY. AS SUCH...THE BEST CHANCE FOR WIDESPREAD
CONVECTION WILL BE WEDNESDAY...ESPECIALLY IF THE FRONT AND SHORT
WAVE MOVE THROUGH DURING THE HEAT OF THE DAY...WHICH WILL SPORT
HIGHS MOSTLY IN THE LOWER 90S.
HEADING INTO THE LATE WEEK...A LOW AMPLITUDE UPPER RIDGE WILL BUILD
OVER THE AREA...WITH SOME MID LEVEL DRYING AND CAPPING TO LIMIT
CONVECTION TO SOME DEGREE. HIGHS WILL STILL BE REACHING THE LOWER
90S EACH DAY...HOWEVER...AND WITH ABUNDANT LOW LEVEL MOISTURE...
SCATTERED DIURNAL STORMS ARE EXPECTED EACH DAY. ACTIVITY WILL BE
MORE FAVORED IN THE AREAS DRIVEN BY DIFFERENTIAL HEATING OFF THE
EASTERN SLOPES AND IN THE EAST IN THE VICINITY OF LOW LEVEL
CONVERGENCE PROVIDED BY LEE TROFFING AND PERHAPS SOME INLAND SEA
BREEZE PENETRATION. MINS THROUGH THE EXTENDED WILL RANGE FROM THE
UPPER 60S TO LOWER 70S.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 140 AM SUNDAY...
THE LAST REMAINING STORMS HAVE DIED OFF EARLY THIS MORNING...THOUGH
WITH A CONTINUED HUMID AIRMASS...ADDITIONAL ISOLATED SHOWERS OR
STORMS MAY STILL POP UP. LOW CLOUDS AND FOG ARE EXPECTED TO DEVELOP
THIS MORNING...THOUGH THE SPOTTY NATURE OF STORMS LAST EVENING MAE
IT DIFFICULT TO PINPOINT WHICH SITES WILL BE MOST ADVERSELY IMPACTED.
IFR CONDITIONS HAVE ALREADY DEVELOPED AT KFAY...AMD RAP FORECAST
SOUNDINGS SHOW IFR STRATUS DEVELOPING AT KRDU AND KRWI BY AS EARLY
AS 08Z. CONFIDENCE IN STRATUS IS LOWER AT KGSO AND KINT WHERE
RAP SOUNDINGS SHOW ONLY A BRIEF PERIOD JUST PRIOR TO 12Z.
AS STRATUS LIFTS AND SCATTERS LATE THIS MORNING...VFR CONDITIONS
WILL REDEVELOP AND ARE...FOR THE MOST PART...EXPECTED TO CONTINUE
THROUGH THE REMAINDER OF THE DAY. A WEAK FRONTAL ZONE SETTLE SOUTH
OVER SC WILL GIVE WAY TO A LIGHT NORTH-NORTHEASTERLY WIND...WITH
JUST A SLIGHT CHANCE OF A FEW ISOLATED SHOWERS AND STORMS DURING THE
AFTERNOON.
LONG TERM: AFTER A RELATIVE LULL IN DIURNAL CONVECTION SUNDAY AND
MONDAY...CHANCES WILL INCREASE FOR SHOWERS AND THUNDERSTORMS FOR
MIDWEEK. THERE WILL BE A CHANCE FOR FOG/LOW STRATUS EACH MORNING
TUESDAY THROUGH THURSDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...BLS
SHORT TERM...BLS
LONG TERM...MLM
AVIATION...ELLIS/BLS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
140 AM EDT SUN JUN 22 2014
.SYNOPSIS..A SURFACE FRONT WILL PUSH SOUTHEAST THROUGH CENTRAL NORTH
CAROLINA TONIGHT. WEAK HIGH PRESSURE WILL EXTEND OVER THE AREA
THROUGH EARLY MONDAY. A SURFACE TROUGH OF LOW PRESSURE RETURNS
TUESDAY THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM SATURDAY...
A BUSY AFTERNOON AND EVENING WITH MULTIPLE CLUSTERS OF MULTICELLULAR
CONVECTION... MUCH OF IT QUITE STRONG BUT GENERALLY JUST BELOW
SEVERE LIMITS. THE LATEST SURFACE ANALYSIS SHOWS A SURFACE LOW OVER
CENTRAL NC WITH A WEAK CONVERGENCE ZONE RUNNING TO ITS EAST AND
WEST... WHILE A MORE SUBSTANTIAL BACKDOOR FRONT EXTENDS THROUGH
CENTRAL VA. A VERY WARM/MOIST (PW 1.5-2.0 IN.) AND UNSTABLE AIR
MASS PERSISTS OVER NC WITH MLCAPE STILL AT 1500-2000 J/KG...
ALTHOUGH CINH HAS GROWN QUICKLY IN RECENT HOURS... AND LOW LEVEL
LAPSE RATES HAVE LOWERED IN PART BY THE NUMEROUS STORMS AND MULTIPLE
OUTFLOWS. SEVERAL OF THE STORMS NEAR THE WEAK CONVERGENCE ZONE
EXHIBITED WEAK BUT DEEP ROTATION EARLIER THIS EVENING AS THEY FED ON
THIS VORTICITY... HOWEVER THIS TOO HAS WANED. THE RECENT RAP MODEL
RUN SHOWS STEADY MID LEVEL DRYING OVERNIGHT ESPECIALLY IN THE NW CWA
WITH PW FALLING NEAR 1.2 IN... ALTHOUGH VALUES HOLD UP IN THE ERN/SE
CWA WITH CONTINUED TALL SKINNY MARGINAL CAPE AND WEAK MBE MOVEMENT
EXPECTED. SO EVEN AFTER THE NUMEROUS STORMS IN THE COASTAL PLAIN
SHIFT SLOWLY EAST OUT OF THE CWA SOON AFTER MIDNIGHT... ADDITIONAL
ISOLATED STORMS OR STORM CLUSTERS FROM THE TRIANGLE EASTWARD CANNOT
BE RULED OUT THROUGH THE NIGHT... AND A FEW OF THESE COULD PRODUCE
LOCALLY HEAVY DOWNPOURS DUE TO THEIR SLOW MOVEMENT. OTHERWISE...
EXPECT AREAS OF FOG AND STRATUS TO FORM ESPECIALLY ACROSS THE
NORTHERN HALF WHERE PARTIAL CLEARING AND MOIST GROUND WILL FOSTER
LOW CLOUD DEVELOPMENT... A SCENARIO CORROBORATED BY LATEST HRRR.
LOWS 68-73... FOLLOWING THE LATEST GLAMP GUIDANCE AND OBSERVED
TRENDS. -GIH
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 230 PM SATURDAY...
SURFACE BOUNDARY/TROUGH IS EXPECTED TO SETTLE SOUTH OF THE AREA ON
SUNDAY AS WEAK SURFACE HIGH PRESSURE OFF THE MID-ATLANTIC COAST
RIDGES SOUTHEASTWARD INTO THE AREA. ALOFT...NWLY FLOW ALOFT WILL
PREVAIL FOR ONE LAST PERIOD...WITH CENTRAL NC REMAINING POISED TO
SEE ADDITIONALLY SHORTWAVE IMPULSES MOVE THROUGH THE AREA.
ASSOCIATED DPVA COUPLED WITH DIURNAL HEATING COULD SUPPORT ISOLATED
TO SLIGHT CHANCE OF SHOWER/STORM JUST ABOUT ANYWHERE ACROSS THE
FORECAST AREA. LOW-LEVEL NELY FLOW WILL COOL THINGS OFF A BIT...WITH
12Z LOW-LEVEL THICKNESSES SUNDAY MORNING OF 1395M A GOOD 10 METERS
BELOW TYPICAL LATE JUNE THICKNESS VALUES. HIGHS RANGING MID 80S
NORTH TO NEAR 90 SOUTH.
HEIGHTS ALOFT BEGIN TO INCREASE OVER THE AREA SUNDAY NIGHT. SURFACE
RIDGE LOOKS TO HOLD IN PLACE BEFORE SUCCUMBING TO RETURN FLOW DURING
THE DAY ON MONDAY. MODELS CONTINUE HINT AT THE POTENTIAL FOR SOME
MORNING STRATUS LATE TOWARDS DAYBREAK. LOWS IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 210 PM SATURDAY...
HIGH PRESSURE RIDGING DOWN THE EAST COAST WILL GRADUALLY SHIFT
OFFSHORE DURING THE DAY ON MONDAY...ALLOWING MOISTURE TO BEGIN TO
INCREASE ON ITS BACK SIDE WITHIN THE RETURN FLOW. THEREFORE...
PRECIP CHANCES WILL INCREASE SLIGHTLY ON MONDAY...MOST NOTICEABLY
ACROSS THE WEST WITHIN THE BEST RETURN FLOW. NEVERTHELESS...COVERAGE
IS EXPECTED TO BE ISOLATED TO WIDELY SCATTERED AT BEST AS A MID
LEVEL RIDGE BUILDS OVERHEAD. HIGHS ARE EXPECTED TO BE IN THE
MID/UPPER 80S TO NEAR 90 DEGREES...WITH OVERNIGHT LOWS GENERALLY IN
THE MID/UPPER 60S TO NEAR 70 DEGREES.
PRECIP CHANCES...MOSTLY DIURNAL IN NATURE...WILL BEGIN TO INCREASE
EVEN MORE ON TUESDAY AND THEN PERSIST FOR THE REMAINDER OF THE LONG
TERM AS MOISTURE CONTINUES TO INCREASE WITHIN THE RETURN FLOW THAT
SETS UP ON THE BACKSIDE OF THE DEPARTING HIGH. IN ADDITION...FLOW
ALOFT WILL BECOME SOUTHWESTERLY (THUS INCREASING DEEP LAYER
MOISTURE) AS LARGE SCALE TROUGHING MOVES OVER THE GREAT LAKES/MS
RIVER VALLEY. SHORTWAVE TROUGHING WILL THEN PROGRESS EAST OVER THE
REGION WEDNESDAY INTO THURSDAY...PROVIDING ADDITIONAL FORCING FOR
PRECIP. RIDGING ALOFT (ALTHOUGH RATHER FLAT) WILL BUILD BACK OVER
THE AREA LATE INTO THE WEEK AND INTO EARLY NEXT WEEKEND...ALLOWING
SOME MID LEVEL DRYING TO OCCUR. NEVERTHELESS...MODERATE TO STRONG
INSTABILITY WILL RESULT IN CONTINUED PRECIP CHANCES...ALTHOUGH
COVERAGE MAY BE SLIGHTLY LESS. HIGHS WILL GENERALLY IN THE UPPER 80S
TO LOWER 90S TO START THE PERIOD WITH LOW TO MID 90S EXPECTED BY THE
END OF THE WEEK. OVERNIGHT LOWS WILL MOSTLY BE IN THE UPPER 60S TO
LOWER 70S.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 140 AM SUNDAY...
THE LAST REMAINING STORMS HAVE DIED OFF EARLY THIS MORNING...THOUGH
WITH A CONTINUED HUMID AIRMASS...ADDITIONAL ISOLATED SHOWERS OR
STORMS MAY STILL POP UP. LOW CLOUDS AND FOG ARE EXPECTED TO DEVELOP
THIS MORNING...THOUGH THE SPOTTY NATURE OF STORMS LAST EVENING MAE
IT DIFFICULT TO PINPOINT WHICH SITES WILL BE MOST ADVERSELY IMPACTED.
IFR CONDITIONS HAVE ALREADY DEVELOPED AT KFAY...AMD RAP FORECAST
SOUNDINGS SHOW IFR STRATUS DEVELOPING AT KRDU AND KRWI BY AS EARLY
AS 08Z. CONFIDENCE IN STRATUS IS LOWER AT KGSO AND KINT WHERE
RAP SOUNDINGS SHOW ONLY A BRIEF PERIOD JUST PRIOR TO 12Z.
AS STRATUS LIFTS AND SCATTERS LATE THIS MORNING...VFR CONDITIONS
WILL REDEVELOP AND ARE...FOR THE MOST PART...EXPECTED TO CONTINUE
THROUGH THE REMAINDER OF THE DAY. A WEAK FRONTAL ZONE SETTLE SOUTH
OVER SC WILL GIVE WAY TO A LIGHT NORTH-NORTHEASTERLY WIND...WITH
JUST A SLIGHT CHANCE OF A FEW ISOLATED SHOWERS AND STORMS DURING THE
AFTERNOON.
LONG TERM: AFTER A RELATIVE LULL IN DIURNAL CONVECTION SUNDAY AND
MONDAY...CHANCES WILL INCREASE FOR SHOWERS AND THUNDERSTORMS FOR
MIDWEEK. THERE WILL BE A CHANCE FOR FOG/LOW STRATUS EACH MORNING
TUESDAY THROUGH THURSDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...HARTFIELD
SHORT TERM...CBL
LONG TERM...KRD
AVIATION...ELLIS/BLS
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
201 AM MDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 901 PM MDT SAT JUN 21 2014
IT LOOKS LIKE THE SEVERE THREAT IS TAPERING OFF SO HAVE ALLOWED
THE SVR TSTM WATCH TO EXPIRE AS SCHEDULED. ISOLD-SCT THUNDERSTORMS
ARE STILL EXPECTED OVERNIGHT AS MODELS INDICATED ABUNDANT MID
LEVEL INSTABILITY. LOCALLY HEAVY RAIN WILL BE POSSIBLE OVER PARTS
OF WESTERN SOUTH DAKOTA.
&&
.SHORT TERM...THIS EVENING THROUGH SUNDAY NIGHT
ISSUED AT 210 PM MDT SAT JUN 21 2014
A BROAD NORTH/SOUTH PRE-FRONTAL SURFACE TROUGH ACROSS
THE WESTERN AND CENTRAL DAKOTAS DOMINATES THE SURFACE MAP THIS
AFTERNOON. THE TROUGH EXTENDS SOUTHWARD FROM A NEARLY STATIONARY LOW
OVER SOUTH CENTRAL CANADA. A WEAK COLD FRONT ALSO EXTENDS SOUTHWARD
FROM THIS LOW THROUGH EASTERN MONTANA AND NORTH CENTRAL WYOMING.
DEWPOINT TEMPERATURES AHEAD OF THE TROUGH IN CENTRAL AND EASTERN
SOUTH DAKOTA ARE IN THE MID 60S...WHILE DEWPOINTS BEHIND THE COLD
FRONT DROP INTO THE MID 40S. ONLY VERY WEAK UPPER LEVEL IMPULSES
ARE DISCERNABLE IN THE MOSTLY ZONAL FLOW ACROSS THE NORTHERN PLAINS
TODAY. SOME WEAK CONVECTION HAS FIRED UP ALONG THE COLD FRONT IN
NORTHEAST WYOMING AND EASTERN MONTANA BUT IR IMAGERY INDICATES
MINIMAL VERTICAL DEVELOPMENT. A WEAKER SURFACE LOW RESIDES OVER
EASTERN COLORADO...SUPPORTING A MOSTLY STATIONARY EAST-WEST WARM
FRONT BOUNDARY ALONG THE NEBRASKA SOUTH DAKOTA BORDER. LITTLE OR NO
CONVECTIVE DEVELOPMENT HAS TAKEN PLACE ALONG THIS BOUNDARY. MORNING
SOUNDINGS AT BOTH UNR AND LBF INDICATE A STRONG CAP BELOW 700 MB
WITH A DRY LAYER JUST OFF THE SURFACE AND THEN UNSTABLE LAPS RATES
AT MID LEVELS. TRIGGER TEMPERATURES AT BOTH LOCATIONS ARE IN THE MID
80S.
THIS EVENING...THE KEY FOR LOCATING THE CONVECTIVE DEVELOPMENT THIS
EVENING WILL BE THE LOCATION OF THE VERY DIFFUSE BOUNDARY COINCIDING
WITH THE WESTERN DAKOTAS TROUGH. THE HRRR GUIDANCE MAINTAINS A LINE
OF THUNDERSTORMS FROM THE SOUTHWEST CORNER OF SOUTH DAKOTA TO
CENTRAL SOUTH DAKOTA AS WELL AS AN AREA OF POST FRONTAL STORMS OVER
NORTHEAST WYOMING. THE COMBINATION OF MID LEVEL INSTABILITY...LARGE
CAPE VALUES OVER 2000 J/KG AND ADEQUATE BULK SHEAR OF 30 TO 40 KTS
WILL SUPPORT SUPERCELL DEVELOPMENT CAPABLE OF PRODUCING STRONG WINDS
GUSTS AND LARGE HAIL. IT APPEARS AT THIS TIME THAT MOST OF THE
ACTION THIS AFTERNOON WILL TAKE PLACE EAST AND SOUTH OF THE BLKHLS
REGION WITH SOMEWHAT WEAKER ACTIVITY OVER NORTHEAST WYOMING.
OVERNIGHT TONIGHT...THE SURFACE FRONT WILL SLOWLY SHIFT SOUTH AND
EAST DURING THE LATE EVENING. STRONG TO SEVERE STORMS ARE LIKELY
ALONG OR NEAR THE FRONTAL BOUNDARY AS IT CONTINUES EASTWARD INTO
CENTRAL SOUTH DAKOTA BY 04Z. A WEAK UPPER LEVEL IMPULSE IS EXPECTED
TO MOVE INTO NORTHEAST WYOMING AND AND A BROAD AREA OF ISENTROPIC
UPGLIDE IS FORECAST TO DEVELOP OVER THE SHALLOW COOL AIR IN WESTERN
SOUTH DAKOTA AND NORTHEAST WYOMING MOSTLY SOUTH OF US HWY 212
RESULTING IN A STRATIFORM PRECIP EVENT FOR AREAS STRETCHING FROM
AROUND THE BLKLHS TO THE MORVR. TEMPERATURES WILL COOL INTO THE 50S
TO LOWER 60S.
SUNDAY...OVERCAST SKIES AND STRATIFORM PRECIP SHOULD BE ONGOING
BEFORE SUN RISE IN NORTHEAST WYOMING AND THE BLKHLS AREA AND SPREAD
TO THE MORVR BEFORE NOON. ISOLATED THUNDERSTORMS ARE POSSIBLE...BUT
THESE SHOULD BE PRETTY WEAK. A MODERATE NORTHWEST BREEZE WILL
ACCOMPANY THE LIGHT RAIN. THE LIGHT RAIN IS EXPECTED TO BEGIN
TAPERING OFF BY 00Z AS THE COOL AIRMASS PUSHES FURTHER SOUTH AND
EAST. COOLER AIR WILL MOVE INTO THE NORTHERN PLAINS...WITH HIGH
TEMPERATURES 10 TO 15 DEGREES COOLER THAN TODAY...ONLY IN THE MID
60S TO UPPER 70S.
SUNDAY NIGHT...DISSIPATING PRECIPITATION AND SOME LINGERING CLOUD
COVER WILL KEEP TEMPERATURES FROM DROPPING BELOW THE LOWER 50S IN
MOST PLACES...UPPER 40S IN NORTHEAST WYOMING AND THE BLKHLS.
&&
.LONG TERM...MONDAY THROUGH SATURDAY
ISSUED AT 210 PM MDT SAT JUN 21 2014
AN UPPER LEVEL RIDGE OVER THE NORTHERN ROCKIES WILL SLOWLY EXPAND
EASTWARD MONDAY THROUGH THURSDAY. BY THURSDAY...AN UPPER LEVEL
TROUGH WILL HAVE DEVELOPED OVER SOUTHWEST CANADA/NORTHWEST US. THE
RESULT WILL BE WEST/NORTHWEST FLOW ALOFT EARLY IN THE PERIOD
TRANSITIONING TO SOUTHWEST FLOW ALOFT BY THE END OF THE WEEK. A
PARADE OF SHORTWAVES WILL BRING TSRA AT TIMES...ESPECIALLY DURING
THE AFTERNOON/EVENING HOURS GIVEN SLOWLY BUILDING THERMAL RIDGE OVER
THE NORTHERN PLAINS AND SUBSEQUENT SLIGHTLY HIGHER MLCIN VALUES.
GFS/ECMWF ARE IN GENERAL AGREEMENT...BUT BOTH HINT AT POSSIBLE BACK
DOOR COOL FRONTS TUESDAY OR WEDNESDAY FOR THE SD PLAINS GIVEN
PROXIMITY OF UPPER LOW OVER HUDSON BAY. DIDN/T DEVIATE MUCH FROM
GUIDANCE VALUES FOR TEMPERATURES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 158 AM MDT SUN JUN 22 2014
SCATTERED SHOWERS AND THUNDERSTOMRS WILL CONTINUE OVERNIGHT...
RESULTING IN RATHER WIDESPREAD PRECIPITATION COVERAGE ACROSS
NORTHEASTERN WY/WESTERN SD. THIS AREA OF PRECIPITATION WILL CAUSE MVFR
CIGS/VSBYS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...10
SHORT TERM...CARPENTER
LONG TERM...HELGESON
AVIATION...MLS
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
347 AM CDT SUN JUN 22 2014
.SHORT TERM (TODAY THROUGH MONDAY)...
A WEAK SHEAR AXIS IS DRAPED ALONG AND NW OF I-35 EARLY THIS
MORNING. LIGHT CONVECTION IS DEVELOPING ALONG THIS AXIS AND IS
DEPICTED FAIRLY WELL BY THE RECENT RUC RUNS. THE SHEAR AXIS IS
EXPECTED BY MODEL CONSENSUS TO SHIFT EAST AND POSSIBLY PUSH THE
HIGHER RAIN CHANCES AND PWAT VALUES INTO EASTERN COUNTIES LATE
TODAY WHILE MID LEVEL STABILITY BUILDS INTO WESTERN AND CENTRAL
COUNTIES. THE INCREASING STABILITY IS SUGGESTED TO BE OVER A
SHORT PERIOD... LASTING THROUGH LATE MONDAY. WITH REDUCED CLOUD
COVER EXPECTED THE MILD AFTERNOON TEMPERATURES OF TODAY SHOULD
REBOUND 2-4 DEGREES WARMER FOR MONDAY.
&&
.LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
A SMALL DISTURBANCE IS EXPECTED TO TRIGGER CONVECTION OVER THE
SOUTHERN PLAINS LATE MONDAY AND POSSIBLY SEND A WEAKENING COMPLEX
OF STORMS INTO THE AREA MONDAY NIGHT INTO TUESDAY. WITH NORTHERLY
MID-LEVEL FLOW DEVELOPING DURING THIS PERIOD...SOME MODELS...
ESPECIALLY THE CANADIAN...DEVELOP A LOW PRESSURE CENTER OVER
CENTRAL TX AND AMPLIFY RAIN CHANCES INTO A POSSIBLE FLOOD PATTERN.
A MORE CONSERVATIVE BLEND OF THE DRIER GFS AND WETTER ECMWF IS
PREFERRED FOR FORECAST CONSISTENCY...BUT WILL NOTE THAT THE
BROADER WEAKNESS OVER TX IS TYPICAL FOR JUNE HEAVY RAIN EVENTS.
BASED ON MODEL CONSENSUS AN ENHANCEMENT OF DIURNAL THUNDERSTORM
ACTIVITY IS PROBABLE FOR AREAS ALONG AND EAST OF I-35 WEDNESDAY
THROUGH SATURDAY...AS EVEN THE DRIER GFS KEEPS A WEAK MID LEVEL
SHEAR AXIS OVER CENTRAL TX THROUGH AS LATE AS THURSDAY.
THE CONSENSUS OF WETTER AND DRIER MODEL SOLUTIONS IN THE EXTENDED
FORECAST CONTINUES TO KEEP TEMPERATURES RELATIVELY MILD.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 90 74 92 74 90 / 30 10 10 20 20
AUSTIN BERGSTROM INTL AIRPORT 90 73 93 73 90 / 30 10 10 20 20
NEW BRAUNFELS MUNI AIRPORT 91 74 93 73 90 / 20 10 10 10 20
BURNET MUNI AIRPORT 87 72 91 72 88 / 20 - 20 20 20
DEL RIO INTL AIRPORT 91 74 96 75 94 / 10 - 10 10 10
GEORGETOWN MUNI AIRPORT 89 73 92 73 90 / 20 10 20 20 20
HONDO MUNI AIRPORT 92 73 93 73 93 / 20 10 10 10 20
SAN MARCOS MUNI AIRPORT 90 74 92 73 90 / 20 10 10 20 20
LA GRANGE - FAYETTE REGIONAL 91 76 93 75 90 / 30 10 20 20 30
SAN ANTONIO INTL AIRPORT 90 76 93 75 90 / 20 10 10 10 20
STINSON MUNI AIRPORT 92 75 94 75 92 / 20 10 10 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...99
SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
1237 AM CDT Sun Jun 22 2014
.AVIATION...
06Z TAF issuance...
The main aviation concern for the next 24 hours is MVFR cigs
affecting CNM, HOB and MAF late tonight through early morning. Have
low stratus developing at HOB and MAF by 22/09Z then improving
conditions around 22/13-14Z. Think the stratus will approach CNM from
the east but not quite sure it will make it. Went ahead and kept
TEMPO from 13-15Z for now. Will need to amend or add low cigs at
other sites if MVFR develops there. Otherwise, VFR conditions are
expected to prevail late morning through the end of this TAF cycle.
&&
PREV DISCUSSION... /ISSUED 212 PM CDT Sat Jun 21 2014/
DISCUSSION...
A well defined Mexican moisture tap is still evident on water vapor
imagery with embedded shrtwv trof/s, one of which is lifting out
the area while another model depicted shrtwv trof follows and in
part is responsible for renewed SHRA/TSRA. The area where SHRA/TSRA
have been occurring is area co-located where 9h-85h mstr flux has
persisted and PWs are near 1.75" per GEFS (about 2.5 standard
deviations above normal). The RUC13 show this area of moisture
flux redeveloping to the n into the n-ne PB and thus we would not
be surprised to SHRA/TSRA develop into the n-ne these next few
hrs. Heavy rain is main concern and local flooding/flash flooding
is possible.
Mid level ridge will slowly builds in from the w and serve to
push the general mid level trof/moisture axis that has been over
the area to the e resulting in a decreased chance of rain and an
increase in temperatures. Still there are some opportunities for
precip. For Sunday PoPs will generally be confined to the mtns
where very steep LR/s of 8-9 c/km are to be coincident with sfc
dwpnts in the m40-50 along e slopes, flow will be upslope, and
CINH will be a non-issue in/near elevated heat sources. Meanwhile
Sunday night storms may near the far NW CWFA with shrtwv trof in
NW flow aloft. On Monday NAM12/ECMWF better depicts a shrtwv trof
in the NW flow and develops storms by mid/late afternoon in E-SE
NM and then in PB after 21Z. Development may be enhanced by a
boundary from previous convection and/or its own cold pool. Timing
will be important, if it does come thru early then there won`t be
much concern for precip into the evening. Tue models hint at tstms
from the mtns into E-SE NM where moist se low level flow and
secondary mid level theta-e ridge are expected to be. ECMWF wants
light up the mtns again Thur/Fri, while the GFS confines precip
moreso to the Davis mtns. As frequently is the case for the mtns
the development is tied to the mid level theta-e ridge axis and
based on consensus of data the Davis mtns are favored over the GDP
mtns. A mid level trof is progged to push in to the n Friday,
which may advect drier air ewd. Through the extended part of the
fcst the GFS is much warmer than ECMWF in part due to its more
veered/stronger wly winds which aids thermal ridge/dry air.
Climatology certainly favors the GFS and with warm temperatures
already in forecast with probably use a blender approach to catch
general trends.
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
27
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
406 AM EDT SUN JUN 22 2014
.SYNOPSIS...
WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND
TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A
DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD
FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE
WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 345 AM EDT SUNDAY...
FORECAST AREA REMAINS BETWEEN UPPER LOW OVER THE NORTHEAST UNITED
STATES AND UPPER RIDGE OVER THE SOUTHERN PLAINS TODAY AND TONIGHT.
NO DISTINCT SHORT WAVES COMING THROUGH THE UPPER FLOW BUT 500 MB
TEMPERATURES DO DROP A FEW DEGREES BY THIS AFTERNOON.
ENOUGH HIGH SURFACE HIGH PRESSURE WAS BUILD IN EAST OF THE BLUE
RIDGE THAT WINDS HAVE COME AROUND TO THE NORTHEAST. LOW CLOUDS HAVE
DEVELOPED IN THE WEDGE AND SPREAD WEST TOWARD THE BLUE RIDGE. OVER
THE MOUNTAINS THE WIND WAS LIGHT FROM THE WEST. THIS WILL CREATE
DIFFERENTIAL HEATING DURING THE DAY AND SOME LOW LEVEL CONVERGENCE.
THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE ALONG THE
CONVERGENCE ZONE ON THE WEST SIDE OF THE LOW CLOUDS WHERE
INSTABILITY WILL BE BETTER.
BUFKIT SHOWED THE THICKNESS OF THE STRATUS WILL ONLY BE A FEW
HUNDRED FEET AND THE SUMMER SUN WILL GRADUALLY ERODE THE LAYER. AS
THE CLOUDS ERODE AND RETREAT BACK THE EAST THE CHANCE OF SHOWERS AND
THUNDERSTORMS WILL ALSO SHIFT EAST. HRRR AND OTHER SHORT TERM
GUIDANCE SHOWED STORMS DEVELOPING NORTH OF THE FORECAST AREA THEN
MOVING SOUTH AND EXTENDING FROM BATH COUNTY TO SURRY COUNTY BY LATE
AFTERNOON.
CLOUDS WILL ALSO CREATE A LARGER SPREAD IN MAXIMUM TEMPERATURES FOR
TODAY. THE SOONER THE CLOUDS MIX OUT THE WARMER IT WILL BE IN THE
EAST. LOW LEVEL MOISTURE FORECASTS SUGGEST CLOUDS WILL FILL BACK IN
EAST OF THE BLUE RIDGE OVERNIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
AS OF 300 AM EDT SUNDAY...
WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS
FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF
APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO
SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM
OFF THE SOUTHEAST COAST.
SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE
OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST
EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY...
WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS
CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF
THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS
TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID
ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF
SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT.
DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS
OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL
BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE...
ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA
WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO
THE DEPARTING SURFACE RIDGE.
WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM
PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT
SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND
THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER
CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K
FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN
LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO
SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY
SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED
TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME.
ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING
AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT
INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER
AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED.
THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL
UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO
RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE
PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE
TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST.
MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND
GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S
CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS
GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY
LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW
BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 140 PM EDT SATURDAY...
I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL
BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK
NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN.
OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY
AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE
WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF
THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING
ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES.
NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS
STAY WELL NORTH OF THE MID ATLANTIC.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
AS OF 130 AM EDT SUNDAY...
LOW PRESSURE WAS OVER EASTERN NORTH CAROLINA WITH A FRONT
TRAILING BACK INTO THE TENNESSEE VALLEY. ENOUGH HIGH PRESSURE WAS
BUILDING INTO THE REGION NORTH OF THIS SYSTEM TO BRING SURFACE
WINDS AROUND TO THE NORTHEAST AT KROA/KLYH/KDAN.
A LAYER OF STRATUS WAS ADVANCING WEST TOWARD THE BLUE RIDGE AND IS
EXPECTED TO REACH KROA AROUND THE START OF THE 06Z TAF PERIOD.
MORE QUESTIONABLE IF WEDGE AND LOW CLOUDS WILL MAKE IT INTO KBCB.
FOR NOW HAVE KEPT IFR CEILINGS OUT OF THE KBCB FORECAST. WEDGE IS
SHALLOW AND CLOUDS WILL ERODE IN THE MORNING WITH HEATING.
ALONG THE EDGE OF THIS RELATIVELY MORE STABLE AIR...MODERATE
CONFIDENCE OF THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS BY
AFTERNOON. ANY PRECIPITATION WILL DIMINISH WITH THE LOSS OF
HEATING THIS EVENING.
CEILINGS MAY LOWER AGAIN OVERNIGHT...ESPECIALLY EAST OF THE BLUE
RIDGE. LOW CONFIDENCE ON TIMING...SO FOR NOW HAVE LEFT RETURN OF
IFR CEILINGS OUT OF TAFS.
EXTENDED AVIATION DISCUSSION...
DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF
AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF
ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET
CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS
OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING
PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE
FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING
FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS
OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE
NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE
PREVIOUS AFTERNOON.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...WERT
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
342 AM CDT SUN JUN 22 2014
.SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
MADE A RATHER SHARP DEVIATION FROM THE PREVIOUS FORECAST FOR THE
NEXT 24 HRS. THE MODELS HAVE SLOWED DOWN THE ARRIVAL OF THE NEXT
TROF...WITH SHORT WAVE RIDGING AND A DRY COLUMN NOW EXPECTED TO KEEP
THE AREA RAIN FREE THROUGH 06Z TONIGHT. IN THE VERY SHORT
TERM...CALM WINDS...DAMP GROUND...A VERY SATURATED BOUNDARY LAYER
AND SOME INFLUENCE FROM LAKE MICHIGAN HAS LEAD TO WIDESPREAD DENSE
FOG ACROSS THE SOUTHEAST. THE WESTERN EDGE IS TOUGH TO DETERMINE
BUT IS SOMEWHERE BETWEEN WATERTOWN AND MADISON. SOME BLOWOFF CIRRUS
FROM CONVECTION UPSTREAM IS HELPING TO KEEP SOUTH CENTRAL AREAS IN
BETTER SHAPE. THE SOUTHEAST IS ALSO UNDER THE INFLUENCE OF A COOLER
SOUTHEAST FLOW OFF THE LAKE. ALBEIT A VERY LIGHT FLOW...BUT IT/S
ENOUGH. A DENSE FOG ADVISORY IS IN EFFECT UNTIL 9 AM FOR ALL BUT THE
FAR WRN TIER OF COUNTIES. I MAY HAVE TO TRIM ANOTHER TIER OUT OF
THE ADVISORY EARLY IF MSN DOESN/T DETERIORATE SOON.
THE NEXT TROF BEGINS TO INFLUENCE THE AREA AFTER MIDNIGHT WITH SOME
DEEP Q-VECTOR CONVERGENCE IMPINGING ON THE AREA. THE LEADING WARM
ADVECTION IS UNIMPRESSIVE SO DON/T SEE MUCH NEED TO TRY TO BRING
THIS IN FASTER THAN THE BULK OF THE GUIDANCE SUGGESTS. CAPE LOOKS
WEAK WITH LOW LEVEL CAPPING. ANY THUNDER WILL BE ELEVATED AND NOT
VERY STRONG. WE COULD SEE SOME FOG AGAIN IN THE EAST AS THE FLOW
WILL BE ONSHORE AGAIN.
MONDAY AND MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
THE VERY SLOW-MOVING MID LEVEL SHORTWAVE WILL TRACK ACROSS WISCONSIN
ON MONDAY. VORTICITY ADVECTION...RIGHT ENTRANCE REGION OF THE UPPER
JET...STRONG 700MB OMEGA AND FRONTOGENESIS LINE UP OVER SOUTHERN WI
MIDDAY MONDAY. RAISED POPS TO CATEGORICAL FOR MUCH OF THE DAY.
EXPECTING SCATTERED THUNDERSTORMS GIVEN TALL SKINNY CAPE OF AROUND
1500 J/KG AND 20 KT BULK SHEAR AND THE FOCUSED SYNOPTIC FORCING.
PRECIPITABLE WATER VALUES OF AROUND 1.75 INCHES AND LOW MBE
VELOCITIES SHOW THE POTENTIAL FOR HEAVY RAIN OVER THE AREA.
RAIN WILL TAPER OFF FROM WEST TO EAST FROM LATE AFTERNOON THROUGH
EVENING. THE GFS IS SLOWER TO END THE PRECIP THAN THE NAM AND ECMWF.
.LONG TERM...
TUESDAY...FORECAST CONFIDENCE MEDIUM.
EXPECTING QUIET WEATHER FOR MOST OF THE DAY TUESDAY WITH DRIER AIR
OVERHEAD AND LACK OF ANY FORCING. A SURFACE TO 850MB COLD FRONT
STATIONED ACROSS NORTHERN WI WILL DROP DOWN THROUGH SOUTHERN WI TUE
NIGHT. THERE IS A CHANCE OF SHOWERS AND MAYBE A THUNDERSTORM ALONG
THIS FRONT OVERNIGHT.
WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE LOW.
THE STALLED 925-850MB FRONT OVER SOUTHWEST WI WILL BE THE FOCUS FOR
POSSIBLE SHOWERS AND A FEW THUNDERSTORMS ON WEDNESDAY WITH A WEAK
SHORTWAVE ROLLING THROUGH. THEN THAT BOUNDARY MAY LIFT INTO NORTHERN
WI FOR THE REST OF THE WEEK AND KEEP SOUTHERN WI ON THE WARM AND
CAPPED SIDE OF THE FRONT PER THE 00Z ECMWF...OR IT COULD STALL RIGHT
OVER SOUTHERN WI AND CONTINUE TO BE THE FOCUS FOR ROUNDS OF SHOWERS
AND THUNDERSTORMS EACH DAY PER THE GFS. THEREFORE...THERE IS A
CHANCE FOR SHOWERS AND THUNDERSTORMS EVERY TIME PERIOD IN THE
EXTENDED FORECAST. TEMPERATURES WILL DEPEND ON THE PRECIP CHANCES.
WENT WITH CONSENSUS FORECAST VALUES.
THE ONE MORE CERTAIN THING IS THAT EASTERLY WINDS WILL PREVAIL
THROUGH THE EXTENDED AND KEEP LAKESHORE TEMPS COOLER.
&&
.AVIATION/12Z TAFS/...
LIFR CONDITIONS WILL CONTINUE ACROSS THE SOUTHEAST THROUGH ABOUT 14-
15Z WITH GRADUALLY IMPROVING CONDITIONS THEREAFTER. THE RAP AND
AMDAR AIRCRAFT SOUNDINGS INDICATE THIS STUFF IS 2-3KFT THICK. THIS
LOOKS VERY SIMILAR TO YESTERDAY. THE RAP HAS THIS MIXING OUT BY
AROUND NOON...GIVE OR TAKE...JUST LIKE YESTERDAY...SO SEE NO REASON
TO DISAGREE. THERE SHOULD ONLY BE SOME HIGH CLOUDS AROUND ONCE THE
LOW STUFF SCATTERS OUT. FOR THE AIR SHOW...HOWEVER...WE SHOULD
STILL SEE SOME LOWER CLOUDS AND FOG OVER THE WATER DUE TO THE MOIST
BOUNDARY LAYER AIR MOVING LITTLE OVER THE COLD WATERS OF THE LAKE.
IT/S POSSIBLE LAKE AREAS WILL CLEAR OUT...BUT CONFIDENCE IS LOW IN
THESE SITUATIONS. FOR KMSN...IMPROVEMENT WILL LIKELY OCCUR MUCH
QUICKER WITH VFR CONDITIONS LIKELY BY 14Z.
AN EASTERLY FLOW CONTINUING TONIGHT COULD BRING IN SOME LOWER VSBYS
AGAIN TO THE SOUTHEAST...BUT THERE WILL BE MUCH MORE FLOW ABOVE THE
DECOUPLED BOUNDARY LAYER SO NOT EXPECTING VSBYS TO BE AS LOW OR FOR
THERE TO BE MUCH IN THE WAY OF LOW STRATUS.
THUNDERSTORMS ARE POSSIBLE AT KMSN TOWARD 12Z MON AS A TROF
APPROACHES FROM THE WEST.
&&
.MARINE...
HAVE EXTENDED THE MARINE DENSE FOG ADVISORY AGAIN...THIS TIME TO 15Z
MON...OR 10 AM MON. JUST NOT SEEING MUCH PATTERN CHANGE OR REASON
FOR SIGGY IMPROVEMENT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR WIZ046-047-
051-052-057>060-063>066-068>072.
LM...DENSE FOG ADVISORY UNTIL 10 AM CDT MONDAY FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
MONDAY THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1151 PM CDT SAT JUN 21 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 345 PM CDT SAT JUN 21 2014
AT 3 PM...A MESOSCALE CONVECTIVE VORTICITY...GENERATED FROM THE
THUNDERSTORMS IN NEBRASKA AND SOUTH DAKOTA LAST EVENING...WAS
MOVING EAST THROUGH SOUTHERN WISCONSIN. THIS SYSTEM IS GENERATING
SHOWERS AND A FEW THUNDERSTORMS IN AN AREA OF 2500 J/KG SURFACE
CAPES. BOTH THE 21.12Z ARW AND LATEST HRRR ARE IN GOOD AGREEMENT
THAT A FEW SHOWERS WILL LINGER ACROSS ADAMS AND JUNEAU COUNTIES IN
CENTRAL WISCONSIN THROUGH 22.03Z...AND THEN THE REMAINDER OF
TONIGHT WILL BE DRY AS SUBSIDENCE BUILDS ACROSS THE AREA IN THE
WAKE OF THE CONVECTIVELY INDUCED VORT MAX AND SHORT WAVE RIDGE.
ON SUNDAY...THE 21.12Z MODELS ARE IN GOOD AGREEMENT THAT SCATTERED
SHOWERS AND THUNDERSTORMS WILL DEVELOP DURING THE MORNING ACROSS
SOUTHEAST MINNESOTA AND NORTHEAST IOWA AHEAD OF AN APPROACHING
COLD FRONT AND SHORT WAVE TROUGH MOVING OUT OF THE CENTRAL PLAINS.
THESE SHOWERS AND THUNDERSTORMS THEN BECOME MORE WIDESPREAD ACROSS
THE ENTIRE FORECAST AREA AS THE UPPER LEVEL DIVERGENCE INCREASES...
THE AREA ENTERS THE RIGHT ENTRANCE REGION OF A 50 KNOT 250 MB
JET...AND THE SURFACE BASE CAPES CLIMB INTO THE 3-4K J/KG RANGE.
WHILE THE MODELS ARE IN AGREEMENT WITH THIS...THEY DO DIFFER SOME
ON HOW ORGANIZED THIS CONVECTION BECOMES DURING THE AFTERNOON. THE
ARW SUGGEST A LINE OF STORMS BY EARLY AFTERNOON. MEANWHILE THE
21.12Z SPC WRF SUGGESTS THAT THE CONVECTION WILL BE LESS
ORGANIZED. WHILE THE 0-3 KM AND 0-6 KM SHEAR IS NOT SUFFICIENT FOR
THE DEVELOPMENT OF SUPERCELLS...THE MID LEVEL LAPSE RATES ARE
RUNNING IN THE 7 TO 8 C/KM RANGE WHICH WOULD BE SUFFICIENT FOR THE
DEVELOPMENT OF LARGE HAIL AND DRY AIR BELOW THE CLOUDS MAY AID IN
STRENGTHENING THE DOWN DRAFTS...SO WILL HAVE TO WATCH OUT FOR
PULSE SEVERE STORMS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 PM CDT SAT JUN 21 2014
FROM SUNDAY NIGHT INTO MONDAY...THE CONVECTION BECOMES MORE
ORGANIZED AS THE COLD FRONT AND SURFACE LOW MOVES SLOWLY THROUGH
THE FORECAST AREA. STRONG 850 MB MOISTURE JET WILL RESULT IN THE
DEVELOPMENT OF A MESOSCALE CONVECTIVE COMPLEX. IN ADDITION...
PRECIPITABLE WATER VALUES CLIMB INTO THE 1.7 TO 1.9 INCH RANGE
AND WARM CLOUD DEPTHS CLIMB TO 4 KM AHEAD OF THE SURFACE LOW.
THIS WILL RESULT IN THE THREAT OF HEAVY RAIN AND POTENTIALLY SOME
MORE FLOODING. WITH MODELS DEVIATING ON THE TIMING...LOCATION OF
THE SURFACE LOW...AND STRENGTH OF THE SHORT WAVE TROUGH...HELD OFF
ISSUING A FLOOD WATCH FOR NOW. WHILE THE 0-6 KM SHEAR REMAINS
WEAK...THE 0-3 KM DOES EXCEED 30 KNOTS AND THIS COULD RESULT IN
SOME WIND DAMAGE AS THE SYSTEM EVOLVES.
MONDAY NIGHT IS NOW LOOKING DRY IN ALL OF THE DETERMINISTIC MODELS
AS SUBSIDENCE DEVELOPS IN THE WAKE OF THE DEPARTING LOW PRESSURE
SYSTEM. AS A RESULT...EITHER REDUCED OR TOOK OUT THE
PRECIPITATION CHANCES ACROSS THE ENTIRE FORECAST AREA.
FROM TUESDAY THROUGH THURSDAY....A CANADIAN COLD FRONT DROPS INTO
THE REGION. WHILE THE MODELS HAVE BEEN CONSISTENT AT DOING THIS...
THEY CONTINUE TO STRUGGLE ON HOW FAR SOUTH THIS FRONT WILL GET.
THE MODELS ALSO CONTINUE TO SHOW THAT SEVERAL SHORT WAVE TROUGHS
WILL MOVE ALONG THIS BOUNDARY. HOWEVER THERE IS ONLY WEAK MOISTURE
TRANSPORT INTO THE REGION WHICH RESULTS IN WEAK 0-3 KM AND 0-6 KM
SHEAR...THUS NOT EXPECTING ANY SEVERE WEATHER AT THIS TIME.
FROM THURSDAY NIGHT INTO SATURDAY...A PATTERN SHIFT OCCURS AS A
LONG WAVE TROUGH MOVES INTO THE WESTERN UNITED STATES. WHILE BOTH
THE GFS AND ECMWF ARE IN AGREEMENT THAT AND UPPER LEVEL RIDGE WILL
BUILD AHEAD OF THIS TROUGH...THERE CONTINUES TO BE QUESTIONS ON
HOW FAR WEST THIS RIDGE WILL END UP AND THIS WILL GREATLY AFFECT
WHETHER WE WILL SEE PRECIPITATION OR NOT. DUE TO THIS...JUTS
STAYED WITH THE MODEL CONSENSUS FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1152 PM CDT SAT JUN 21 2014
MAIN WEATHER STORY OCCURS SUNDAY AT TAF SITES AS INSTABILITY
BUILDS BACK INTO THE AREA FROM THE WEST AND STORMS LOOK MORE
FAVORABLE AS THE DAY PROGRESSES. IN THE MORNING...IT APPEARS AN
INSTABILITY GRADIENT WILL BE WEST OF KRST WITH DAKOTAS STORMS
MOVING TO ABOUT I-35 IN MN/IA...THEN WEAKEN RAPIDLY LEAVING DEBRIS
CLOUD INTO KRST AND KLSE. THERE COULD BE SOME RAIN TOO...WILL HAVE
TO LET THIS FORECAST IN THE SHORT TERM...HOWEVER THERE DOES NOT
LOOK TO BE A FLIGHT RESTRICTION WITH IT.
LATER IN THE AFTERNOON INSTABILITY WILL BE BUILDING AND A FRONT
WILL WORK OUT OF THE WEST VERY SLOWLY. VERY MOIST AIR WILL MOVE IN
BY EVENING WITH INCREASING STORM AND HEAVY RAIN
CHANCES...ESPECIALLY FOR KRST. AFTER 06Z...EXPECT CIGS/VSBYS TO
COME DOWN IN RAIN AND STORMS.
&&
.HYDROLOGY...
ISSUED AT 345 PM CDT SAT JUN 21 2014
THE MISSISSIPPI TRIBUTARIES HAVE CRESTED AND ARE NOW FALLING.
MEANWHILE THE MISSISSIPPI RIVER IS RISING WITH FLOODING EXPECTED
AT WABASHA...WINONA...AND MCGREGOR. AT THIS TIME...LA CROSSE IS
NOT EXPECTED TO REACH FLOOD STAGE. HOWEVER THIS COULD CHANGE
DEPENDING ON HOW MUCH RAIN FALLS ON SUNDAY NIGHT.
BETWEEN 1 AND 3 INCHES OF RAIN LOOKS POSSIBLE ON SUNDAY
NIGHT...BUT DUE TO MODEL INCONSISTENCIES HELD OFF ISSUING A FLOOD
WATCH FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...BAUMGARDT
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1036 PM MDT SAT JUN 21 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 307 PM MDT SAT JUN 21 2014
STORMS HAVE DEVELOPED EARLY THIS AFTN OVER GOSHEN COUNTY AND HAVE
MOVED INTO THE CENTRAL AND NORTHERN PANHANDLE. THEY HAVE STRUGGLED
TO BECOME DISCRETE SO FAR DUE TO THE MARGINAL DEEP LAYER SHEAR
(25-30 KTS) AND HAVE FORMED INTO LINES/CLUSTERS. SPC MESOANALYSIS
SHOWS GOOD INSTABILITY WITH MLCAPES OF 1500-2000 J/KG OVER THE
PANHANDLE. BELIEVE THAT THE MAIN SVR THREAT DURING THE AFTN WILL
BE DAMAGING WINDS WITH THE HIGH LCLS AND DEEP BOUNDARY LAYER OVER
THE PANHANDLE. LARGE HAIL IS LESS OF THE THREAT WITH THE MARGINAL
DEEP LAYER SHEAR...HOWEVER MARGINALLY SVR HAIL WILL BE POSSIBLE. A
SEVERE THUNDERSTORM WATCH WAS ISSUED FOR ALL OF THE NEBRASKA
PANHANDLE THROUGH 03Z. ALL OF THIS STORM ACTIVITY IS OCCURING
AHEAD OF A SHORTWAVE THAT IS CURRENTLY LOCATED OVER WESTERN
COLORADO. THE HRRR MODEL SHOWS MOST STORMS PUSHING EAST OUT OF THE
CWA BY AROUND 00Z.
COLD FRONT BEHIND THE SHORTWAVE WILL PUSH ACROSS THE PLAINS LATE
TONIGHT AND SUNDAY MORNING. WINDS ARE STILL NORTHERLY AT 18Z SUN
AND THEN BECOME MORE NORTHEASTERLY DURING THE AFTN. MODELS HAVE
DECREASED INSTABILITY A BIT OVER YESTERDAYS RUN WITH LI VALUES OF
AROUND -3C IN LARAMIE/PLATTE COUNTIES AND EXTENDING EASTWARD ALONG
THE COLORADO BORDER. STORMS SHOULD DEVELOP BY AFTN IN THE
CONVERGENCE ALONG THE SOUTHERN LARAMIE RANGE...HOWEVER DO NOT
BELIEVE THEY WILL BECOME SVR AS THEY PUSH EASTWARD. STORM COVERAGE
WILL BE MORE LIMITED OVER THE PANHANDLE AS THE AIRMASS IS MORE
STABLE POST FRONTAL. TEMPS WILL BE 10-15 DEGREES COOLER ON SUNDAY.
FOR MONDAY SFC WINDS BECOME MORE SOUTHEASTERLY AND AIRMASS IS MORE
UNSTABLE THAN SUNDAY IN AREAS NEAR THE COLORADO BORDER. THIS IS
THE DAY AFTER THE FROPA...WHICH OFTEN TIMES LEADS TO A GREATER SVR
THREAT. NORTHWESTERLY FLOW ALOFT IS STRONG ENOUGH...COMBINED WITH
THE SOUTHEAST LLVL FLOW...TO PRODUCE 40-45 KTS OF DEEP LAYER SHEAR
SO THERE WILL LIKELY BE SOME SVR POTENTIAL ON MONDAY IN AREAS
ALONG INTERSTATE 80.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 307 PM MDT SAT JUN 21 2014
THE ACTIVE PATTERN WILL CONTINUE INTO NEXT WEEK AS ZONAL FLOW
BECOMES MORE SOUTHWESTERLY BY THE END OF THE WEEK. BOTH THE GFS
AND EURO SOLUTIONS CONTINUE TO ADVERTISE DAILY CHANCES OF
AFTERNOON AND EVENING CONVECTION AS SOUTHEASTERLY LLVL RETURN FLOW
PERSISTS ALL WEEK. THIS WILL RESULT IN PERSISTENT THETA-E RIDGING
OVER MUCH OF THE CWFA THROUGH THE ENTIRE WEEK. TUESDAY WILL BE THE
SECOND DAY POST-FRONTAL...WHICH WHEN COMBINED WITH 0-6KM SHEAR OF
40-50 KNOTS SHOULD SET THE STAGE FOR AN ACTIVE SEVERE WEATHER DAY.
THE GREATEST THREAT WILL BE EAST OF THE LARAMIE RANGE. PROGD
SBCAPES WILL FLARE TO BETWEEN 2000-3000 J/KG FOR WED AND
THU...WHICH SHOULD BE MORE THAN ENOUGH TO COMPENSATE FOR SOMEWHAT
LIGHTER VALUES OF DEEP LAYER SHEAR. WOULD EXPECT SEVERE POTENTIAL
TO CONTINUE FOR BOTH WED AND THU MAINLY EAST OF THE LARAMIE RANGE
AS WELL. TROUGH WILL SWING THROUGH ON FRIDAY...DRAGGING A PACIFIC
FRONT THRU THE AREA WHICH WILL EFFECTIVELY SHUNT BEST INSTABILITY
EAST OVER CENTRAL NEBRASKA FOR BOTH FRIDAY AND SATURDAY. AS A
RESULT...EXPECT THUNDERSTORM CHANCES TO TURN MORE ISOLATED EARLY
NEXT WEEKEND. TEMPERATURES WILL BE SEASONALLY PERSISTENT THROUGH
THE PERIOD WITH 70S ON TUESDAY WARMING INTO THE 80S AT LOWER
ELEVATIONS FOR THE REMAINDER OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING)
ISSUED AT 1029 PM MDT SAT JUN 21 2014
SHOWERS AND THUNDERSTORMS SLOWLY COMING TO AN END OUT IN THE
NORTHERN NEBRASKA PANHANDLE. STILL A LARGE AREA OF SHOWERS ACROSS
NORTHERN WYOMING THAT WILL SAG SOUTH WITH A COLD FRONT SUNDAY.
FRONT IS A LITTLE SLOWER NOW ON FORECAST MODELS THAN ORIGINALLY
FORECAST...SO WE ARE LOOKING AT THIS FRONT TO MAKE IT DOWN TO THE
CHEYENNE AREA PROBABLY EARLY SUNDAY MORNING AFTER 12Z. THIS WILL
KEEP THE WIDESPREAD MVFR/IFR STRATUS FROM FORMING AS THE SUN WILL
BE UP PRIOR TO THE FRONT MAKING IT INTO SOUTHERN WYOMING.
STILL...CONVECTION SHOULD BE WIDESPREAD SUNDAY AFTERNOON AND THE
PANHANDLE AIRPORTS SHOULD SEE THE BULK OF THIS CONVECTION.
&&
.FIRE WEATHER...
ISSUED AT 307 PM MDT SAT JUN 21 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK. MINIMUM
RELATIVE HUMIDITY VALUES WILL BE AROUND 15 PERCENT THIS AFTERNOON
FOR AREAS TO THE WEST OF THE LARAMIE RANGE. WEST WINDS WILL GUST TO
20-25 MPH THROUGH EARLY EVENING. SINCE FUELS ARE STILL GREEN ENOUGH
TO NOT SUPPORT FIRE GROWTH...NO CRITICAL FIRE WEATHER THREAT IS
EXPECTED. COOLER TEMPERATURES ON SUNDAY THROUGH EARLY NEXT WEEK
WILL CAUSE AFTERNOON HUMIDITY VALUES TO INCREASE TO THE 20-30
PERCENT RANGE FOR AREAS TO THE WEST OF THE LARAMIE RANGE. SCATTERED
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH AFTERNOON THROUGH
THE MIDDLE OF NEXT WEEK...WITH COVERAGE HIGHEST TO THE EAST OF THE
LARAMIE RANGE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...HAHN
AVIATION...CLAYCOMB
FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
952 AM MDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 933 AM MDT SUN JUN 22 2014
WATER VAPOR IMAGERY SHOWING WEAK UPPER LEVEL WAVE OVER THE GREAT
BASIN WHICH WILL MOVE OVER COLORADO THIS AFTERNOON AND EVENING AND
WILL PROVIDE SOME WEAK ASCENT. OVERALL MOISTURE VALUES ARE
TRENDING SLIGHTLY HIGHER THAN YESTERDAY AT THIS TIME WITH SURFACE
DEWPOINTS NOW IN THE UPPER 40S TO THE MID 50S OVER LOWER
ELEVATIONS. LATEST ACARS SOUNDINGS SHOWING SUBSTANTIAL CAP AROUND
750 MB SO FURTHER HEATING NEEDED. THUNDERSTORM DEVELOPMENT MAY BE
A BIT LATER THIS AFTERNOON THAN YESTERDAY GIVEN HIGHER INITIAL
STABILITY. NOT A LOT OF MODEL CONSENSUS WITH STORM INITIATION
TODAY AS NAM/RAP SHOWING MUCH OF THE STORMS ALONG A OUTFLOW
BOUNDARY/FRONT WHICH BACKS INTO NORTHEAST COLORADO FROM NEBRASKA
LATER THIS AFTERNOON. MEANWHILE THE HRRR HAS A MORE WEST TO EAST
PROGRESSION OF STORMS THIS AFTERNOON. MAIN CHANGE TO FORECAST WAS
TO LOWER POPS A BIT OVER MOUNTAINS AND FOOTHILLS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 200 AM MDT SUN JUN 22 2014
MESSY SURFACE PATTERN THIS MORNING...BUT GENERAL TREND OF PRESSURE
RISES TO OUR NORTH. EDGE OF COOLER/MOISTER AIR ALONG THE EDGE OF
OUTFLOW FROM SEVERAL ROUNDS OF STORMS ACROSS WYOMING/NEBRASKA...
ROUGHLY AKRON TO TORRINGTON AND NORTHWEST FROM THERE. PRESSURE
RISES APPEAR TO BE BETTER ORGANIZED AGAIN AT THE MOMENT...SO THE
IDEA OF THIS BOUNDARY MOVING SOUTH ACROSS THE AREA THIS MORNING
STILL LOOKS GOOD. AT FIRST THIS AIR WILL BE COOLER...WITH A LOW
LEVEL INVERSION HOLDING BACK CONVECTION THIS MORNING. SEVERAL
THINGS HAPPEN THIS AFTERNOON THAT SHOULD EVENTUALLY RESULT IN
DECENT THUNDERSTORM COVERAGE. FIRST...LIFT AND A LITTLE COOLING
ALOFT MOVES IN FROM THE WEST...DESTABILIZING THE DEEPER
ATMOSPHERE. SECOND...CONTINUED DEEPENING OF THE SURFACE COOL LAYER
WHICH WILL ERODE THE LOW LEVEL CAP. THIRD...LIKELY OUTFLOW FROM
ADDITIONAL CONVECTION NORTH OF US WHICH SHOULD PROVIDE BETTER
MOISTURE FROM THE NEBRASKA PANHANDLE. THIS WILL INCREASE CAPE
VALUES AND WIPE OUT THE CAP LATE IN THE DAY.
ENVIRONMENT WILL EVENTUALLY HAVE MORE MOISTURE THAN THE LAST FEW
DAYS...BUT THE BIGGEST DIFFERENCE WILL BE THE INCREASING SHEAR AS
THE DAY GOES ON. BY THIS EVENING THE 0-6 KM SHEAR WILL BE UP
AROUND 40 KNOTS. CAPE VALUES SHOULD BE IN THE 1000-1500 J/KG RANGE
BUT WITH THAT AMOUNT OF SHEAR THIS SHOULD BE ENOUGH FOR SEVERE HAIL
PRODUCTION...AND EVENTUALLY TO ALLOW ENOUGH ORGANIZATION FOR SOME
WIND THREAT AS WELL. INITIALLY THE NORTH SIDE OF STORMS WILL BE
FAVORED...COULD BE CONVECTION MOVING NORTHEAST OFF OF THE
FOOTHILLS AND THE FRONTAL BOUNDARY...OR STORMS THAT SPLIT WITH THE
LEFT SIDE FAVORED. LATER THIS EVENING THE SHEAR WILL BECOME MORE
LINEAR...WITH CONVERGENCE ON THE FRONT HELPING KEEP THINGS MOVING
DESPITE SLOW MEAN WINDS AROUND 10 KNOTS. SOME CONCERN ABOUT
INCREASING MOISTURE AND INSTABILITY WITH SLOW STORM MOTIONS...BUT
OVERALL WIND PATTERN DOES NOT APPEAR TO LEND ITSELF TO
TRAINING/BACKBUILDING WITH THE POSSIBLE EXCEPTION OF REGENERATION
OVER THE FOOTHILLS. SEE HYDROLOGY SECTION BELOW FOR MORE.
SOME OF THE MODELS WANT TO END CONVECTION EARLY THIS EVENING...I
AM SKEPTICAL OF THIS GIVEN THAT THE UPSLOPE FLOW SHOULD BE
CONTINUING INTO THE EVENING AND THE POTENTIAL FOR MOIST OUTFLOW TO
GENERATE NEW CONVECTION. I SHIFTED THE POPS MORE TO THE LATE
AFTERNOON AND EVENING PERIODS WHERE IT APPEARS THE BEST MOISTURE
AND INSTABILITY SHOULD BE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 200 AM MDT SUN JUN 22 2014
MONDAY AND MONDAY NIGHT...A MODERATE NORTHWESTERLY FLOW ALOFT WILL
BE OVER NORTHERN CO WITH AN UPPER RIDGE TO THE WEST. AT THE
SFC...HIGH PRESSURE WILL BE OVER THE NORTHEAST PLAINS WITH ELY
WINDS ADVECTING BETTER MOISTURE INTO THE URBAN CORRIDOR. FORECAST
SOUNDINGS IN THE AFTN SHOW GOOD INSTABILITY WITH CAPES AROUND
1100 J/KG AROUND DENVER AND AKRON...WITH HIGHER VALUES OF 1600
J/KG AT LIMON. PW VALUES CLIMB TO AROUND 1 INCH OVER THE NERN
PLAINS AND NEAR 0.75 INCHES IN DENVER. FAVORABLE SHEAR PROFILE FOR
SEVERE THUNDERSTORMS IN THE AFTN AND EVENING WITH DAMAGING WINDS
AND LARGE HAIL THE MAIN THREATS. LOW LEVEL ESELY WINDS WL LIKELY
SET UP A DENVER CYCLONE WITH THE POTENTIAL FOR A WEAK LANDSPOUT OR
TWO ALONG THE BOUNDARY. MDLS CONTINUE TO PRODUCE SOME QPF ACROSS
THE NERN PLAINS OVERNIGHT. NOT MUCH CHANGE REALLY FOR
TUESDAY...THE FLOW ALOFT MAY BE A BIT WEAKER AND SLIGHTLY WARMER
TEMPERATURES WILL ALLOW FOR GREATER INSTABILITY IN THE AFTN. WITH
THE HIGHER PW VALUES AND SLOWER STORM MOTIONS...THE POTENTIAL FOR
HEAVY RAIN PRODUCING TSTMS WILL ADD TO THE ALREADY PRESENT SEVERE
TSTM THREAT. THE UPPER LEVEL RIDGE WILL TRANSITION ACROSS ERN CO
BY WEDNESDAY...WITH A DRIER SOUTHWESTERLY FLOW ALOFT OVER
COLORADO. IN THE LOWER LEVELS...THERE MAY BE SOME DRYING ALONG THE
URBAN CORRIDOR...BUT THE NERN PLAINS WILL REMAIN MOIST. BEST TSTMS
COVERAGE WILL BE EAST OF THE I-25 CORRIDOR...WITH LESSENING POPS
TO THE WEST. THE TREND FOR WARMER AND DRIER CONDITIONS WILL
CONTINUE FOR THURSDAY AND FRIDAY. COOLER CONDITIONS ARE THEN
PROGGED TO RETURN BY SATURDAY. THE MDLS VARY QUITE A BIT WITH THE
OVERALL PATTERN AS THE NEXT SYSTEM FM THE PAC NORTHWEST BRINGS
COOLER WEATHER WITH A BETTER CHANCE FOR TSTMS. THE GFS KEEPS THIS
SYSTEM MORE TO THE NORTH LATE FRIDAY INTO SATURDAY...WHILE THE
ECMWF AND CANADIAN MDLS ARE SLOWER AND DIG THE TROUGH INTO THE
GREAT BASIN ON FRIDAY. NO CHANGES TO THE GRIDS AT THIS TIME...WL
KEEP POPS ON THE LOW SIDE WITH SO MUCH UNCERTAINTY PRESENT.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z MONDAY MORNING)
ISSUED AT 933 AM MDT SUN JUN 22 2014
THERE IS SOME LIGHT NORTHWEST WINDS AT LOCAL TERMINALS BUT THE
FORECAST OF NORTHEAST WINDS AT 18Z MAY NOT MATERIALIZE AS FRONTAL
BOUNDARY WAS WEAKER THAN EXPECTED. THERE COULD BE A STRONGER
FRONTAL PUSH LATER THIS AFTERNOON WITH ADDITIONAL STORMS BUT
OVERALL CONFIDENCE IS LOW. OVERALL WON`T CHANGE MUCH WITHOUT A
CLEAR SIGNAL.
&&
.HYDROLOGY...
ISSUED AT 200 AM MDT SUN JUN 22 2014
INCREASED MOISTURE AND INSTABILITY TODAY WILL COMBINE WITH SLOW
STORM MOTIONS TO PRODUCE A THREAT OF HEAVY RAINFALL. IN GENERAL
THUNDERSTORMS ARE EXPECTED TO BE MOVING...BUT SLOWLY. RAINFALL
AMOUNTS OF UP TO AN INCH IN AN HOUR ARE POSSIBLE WITH THE STRONGER
STORMS NEAR THE FRONT RANGE THIS AFTERNOON. ON THE PLAINS MOISTURE
WILL BE GREATER BY THIS EVENING...WITH 2 TO 3 INCHES IN 1 TO 2
HOURS POSSIBLE. THE HEAVIER END OF THESE AMOUNTS MAY BE ENOUGH TO
CAUSE FLASH FLOODING. WHILE THE HEAVY RAIN THREAT IS MAINLY ON THE
PLAINS...THERE IS SOME THREAT TO THE FRONT RANGE FOOTHILLS...
ESPECIALLY BETWEEN 3 PM AND 9 PM WHEN THERE COULD BE SUSTAINED
EASTERLY WINDS THAT COULD PRODUCE REPEATED THUNDERSTORM CELLS.
WITH LIMITED MOISTURE AND NO CLEAR FOCUS...AT THIS TIME THE THREAT
DOES NOT APPEAR HIGH ENOUGH TO WARRANT A FLASH FLOOD WATCH. AREAS
WEST OF THE FRONT RANGE WILL HAVE LESS MOISTURE.
FOR MONDAY AND TUESDAY...A STATIONARY FRONT WILL BE PARKED ALONG
THE FRONT RANGE AND PALMER DIVIDE WITH WEAK ESELY SFC WINDS.
HIGHER PW VALUES WILL BE PRESENT. THE STORM MOTIONS ON MONDAY WILL
HELP TO OFFSET THE HEAVY RAIN POTENTIAL SOMEWHAT. SLIGHTLY LESSER STORM
MOTIONS ON TUESDAY MAY ELEVATE THE POTENTIAL FOR FLASH FLOODING.
IT WILL DRY OUT FROM THE URBAN CORRIDOR WESTWARD ON WEDNESDAY...
BUT POTENTIAL FOR HEAVIER RAIN PRODUCING TSTMS WL CONTINUE OVER
THE NORTHEAST PLAINS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ENTREKIN
SHORT TERM...GIMMESTAD
LONG TERM...COOPER
AVIATION...ENTREKIN
HYDROLOGY...COOPER/GIMMESTAD
Area Forecast Discussion
National Weather Service Lincoln IL
1005 AM CDT Sun Jun 22 2014
.DISCUSSION...
ISSUED 1005 AM CDT Sun Jun 22 2014
Convection developed just southwest of our CWA earlier this
morning, along the remnants of the outflow boundary from
yesterday`s storms. Latest surface map shows this boundary arcing
northwest along the Mississippi River then into central Iowa,
where a line of strong storms was moving through that area. Have
been seeing some increase in showers recently along this boundary
in the northeast corner of Missouri, and this should increase over
the next few hours. Latest RAP and HRRR guidance showing the
western CWA still with the best chances for showers/storms today,
with some more isolated activity across the east.
Have updated the zones/grids to reflect the storms mainly being
during the afternoon, as well as some adjustments to the sky
cover. Temperatures are largely in good shape and only required
some minor adjustments over the next few hours.
Geelhart
&&
.AVIATION...
ISSUED 651 AM CDT Sun Jun 22 2014
Weak high pressure over IL will provide light and variable winds
with light fog early this morning. Ground fog has generally
remained clear of the TAF sites, but is lingering in nearby fields
per surrounding observations. Will keep all TAF sites VFR this
morning as a result. Next concern is when storms will develop over
the next 24 hours. There remains a large spread in the model
guidance on storm initiation and coverage. The GFS remains the
most aggressive with storms later this afternoon and evening. The
00z NAM, Canadian, and ECMWF have slowed down the development of
storms until possibly later tonight, and mainly west of I-55. The
HRRR 3km model is still indicating a line of storms reaching near
the IL river by 00z this evening, but is the outlier of the latest
runs of the high res models. Will only include a VCSH later
tonight after 09z for now. Would not be surprised to see a pop-up
shower or storm late this afternoon and evening.
Winds will remain generally light and variable due to a weak
pressure gradient. Some southerly winds may develop for PIA and
SPI as the next shortwave aloft approaches IL this afternoon.
Wind speeds should remain less than 10kt at all terminal sites.
Shimon
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun Jun 22 2014
Though an area of showers and thunderstorms moved across much of
ILX yesterday evening, the air mass overall remains very much the
same. Hot and humid conditions persist. A weak frontal boundary
has meandered just north of the area and the next couple of
impulses are just to the west, lining up for arrival later today.
In between waves, much of this morning may be dry in most
locations. Not taking out the possibility for some very isolated
showers...but chances will increase this afternoon/later this
evening with the approach of the next wave. Surface low associated
with the next wave is weak and as a result, models are not doing
well with its evolution in the weak pattern as a whole. Models
continue to over produce the coverage of the convection, then
suffer the feedback issues. Chance/slight chance dominates, with
some minor adjustments for drier pds. Temps above normal and heat
indices in the 90s to wrap up the weekend until the next cool
front moves through Mon/Mon afternoon.
SHORT TERM...Today and tonight...
Hot. Humid. Heat indices into the mid 90s and chances of precip
increasing into the afternoon/evening hours. Waves to the west
showing varied paths and models connecting the dots on the qpf
leave a lot to be desired. Waves passing north and south remain a
possibility, but diurnal impacts and enhancement is just too
strong a possibility with leftover outflows in the region to NOT
have pops around this evening. Very similar tune to the trend from
the past few days. Coverage sporadic, plenty of ingredients to
work with, just non consistent triggers.
LONG TERM...Monday through Friday...
Upper trof/wave pushing through the region on Monday into Tuesday
bringing signif chance, increasing from Sun night into Monday
night. Models speeding up with initial arrival of boundary on
Monday, and slowing its departure...as this run has been a little
more diffuse with the pops and may see this trending with a +/- 12
hrs on either side. Not an absolute at this point, but
Monday/Monday night having the best chances at significant precip
through the fcst. A slightly cooler Tuesday through the end
of the week. Still warm, but potentially less humidity as winds
become more westerly on Tuesday, picking up a northerly component
by Wednesday. Forecast trending drier from late Tuesday through
Wednesday. Another wave Thursday brings back some pops ahead of
the next big storm system developing over the SW for late next
weekend.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1004 AM CDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 1004 AM CDT SUN JUN 22 2014
HAVE INCREASED POPS WEST OF THE MS RIVER AS MCS CONTINUES TO MAKE
SLOW BUT STEADY PROGRESS ACROSS CENTRAL IA. PLENTY OF SUNSHINE IN
EASTERN IA AHEAD OF THE MCS WITH SBCAPES ALREADY NEARING 3000 J/KG
WITH DCAPE ALSO INCREASING. SPC HAS ADDED EASTERN IA TO A SLIGHT
RISK FOR THIS AFTERNOON WITH DAMAGING WIND THE MAIN THREAT WITH
MARGINAL SEVERE HAIL ALSO. STORMS WILL BE MOVING RATHER SLOWLY SO
TORRENTIAL RAINS WILL ALSO BE A CONCERN AS PRECIPITABLE WATERS
INCREASE TO OVER 1.50 INCHES. THERE WILL BE THE POTENTIAL FOR LOCALIZED
FLASH FLOODING ESPECIALLY WHERE HEAVY RAINS HAVE FALLEN IN THE
PAST WEEK.
&&
.SYNOPSIS...
ISSUED AT 249 AM CDT SUN JUN 22 2014
LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH
A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE
CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL
ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN
PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB
WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING
WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA
CURRENTLY HEADED EAST-SOUTHEASTWARD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY.
RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY
OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS
LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING
AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF
THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC.
STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC.
BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST
THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY
OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER
RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA.
CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN
SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES
HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A
BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT
AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE
REGION.
DMD
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN
NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING
OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN
UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW
SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN
AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS
WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE
FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY
ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING
SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS
THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH
ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING
NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE
ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE
ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST
INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH
PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER
DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS
ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF
WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT.
TUE-TUE NIGHT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP
WITH WEAK SUBSIDENCE IN WAKE OF FRONT.
WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL
DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO
SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS
TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY
BY LATE WEEK AND ESPECIALLY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 703 AM CDT SUN JUN 22 2014
A LARGE THUNDERSTORM COMPLEX OVER WESTERN IOWA IS EXPECTED TO
CONTINUE TO WEAKEN AS IT MOVES INTO EASTERN IOWA. HOWEVER...ADDITIONAL
SHOWERS AND STORMS SHOULD DEVELOP AHEAD OF THIS COMPLEX FROM MID
DAY THROUGH THE AFTERNOON. THUS...THUNDERSTORMS ARE EXPECTED TO
AFFECT AREA TAF SITES FROM EARLY AFTERNOON INTO THE EVENING...WITH MVFR
AND POSSIBLY LOCAL IFR CONDITIONS. THUNDERSTORM CHANCES WILL
CONTINUE THROUGH THE OVERNIGHT HOURS AND INTO MONDAY.
DMD
&&
.HYDROLOGY...
ISSUED AT 249 AM CDT SUN JUN 22 2014
AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE
MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN
RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY
RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND
HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN
THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT
RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE
GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA.
WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS
IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY
DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE
LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY
UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE
FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT
BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD
A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS
NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS
WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO
WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION
NEXT COUPLE OF DAYS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...DMD
SHORT TERM...DMD
LONG TERM...05
AVIATION...DMD
HYDROLOGY...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
713 AM CDT SUN JUN 22 2014
.SYNOPSIS...
ISSUED AT 249 AM CDT SUN JUN 22 2014
LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH
A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE
CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL
ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN
PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB
WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING
WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA
CURRENTLY HEADED EAST-SOUTHEASTWARD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY.
RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY
OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS
LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING
AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF
THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC.
STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC.
BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST
THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY
OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER
RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA.
CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN
SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES
HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A
BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT
AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE
REGION.
DMD
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN
NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING
OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN
UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW
SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN
AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS
WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE
FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY
ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING
SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS
THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH
ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING
NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE
ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE
ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST
INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH
PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER
DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS
ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF
WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT.
TUE-TUE NIGHT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP
WITH WEAK SUBSIDENCE IN WAKE OF FRONT.
WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL
DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO
SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS
TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY
BY LATE WEEK AND ESPECIALLY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 703 AM CDT SUN JUN 22 2014
A LARGE THUNDERSTORM COMPLEX OVER WESTERN IOWA IS EXPECTED TO
CONTINUE TO WEAKEN AS IT MOVES INTO EASTERN IOWA. HOWEVER...ADDITIONAL
SHOWERS AND STORMS SHOULD DEVELOP AHEAD OF THIS COMPLEX FROM MID
DAY THROUGH THE AFTERNOON. THUS...THUNDERSTORMS ARE EXPECTED TO
AFFECT AREA TAF SITES FROM EARLY AFTERNOON INTO THE EVENING...WITH MVFR
AND POSSIBLY LOCAL IFR CONDITIONS. THUNDERSTORM CHANCES WILL
CONTINUE THROUGH THE OVERNIGHT HOURS AND INTO MONDAY.
DMD
&&
.HYDROLOGY...
ISSUED AT 249 AM CDT SUN JUN 22 2014
AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE
MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN
RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY
RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND
HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN
THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT
RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE
GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA.
WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS
IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY
DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE
LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY
UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE
FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT
BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD
A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS
NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS
WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO
WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION
NEXT COUPLE OF DAYS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...DMD
SHORT TERM...DMD
LONG TERM...05
AVIATION...DMD
HYDROLOGY...05
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
713 AM EDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 705 AM EDT SUN JUN 22 2014
THE DENSE FOG ADVISORY REMAINS IN EFFECT FOR THE SOUTHWEST PART OF
THE CWA. IT WAS SENT OUT A BIT EARLIER AS I35...W39...LOZ AND SME ALL
WERE REPORTING DENSE FOG. THE DENSE FOG IN THAT AREA SHOULD LIFT AND
BEGIN TO DISSIPATE BY 9 AM EDT. HOURLY TEMPERATURE AND DEWPOINT GRIDS
AS WELL AS SKY COVER HAS BEEN ADJUSTED BASED ON RECENT TRENDS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 355 AM EDT SUN JUN 22 2014
THE PATTERN ACROSS THE CONUS REMAINS RATHER ZONAL THIS MORNING. AN
UPPER LEVEL RIDGE WAS CENTERED OVER THE WESTERN GULF OF MEXICO REGION
AND SOUTHEASTERN CONUS AND EXTENDED INTO THE MS VALLEY. A TROUGH IS GRADUALLY
DEPARTING THE NORTHEASTERN CONUS. THIS PUTS THE REGION IN WEST
NORTHWEST TO NORTHWEST FLOW ALOFT WITH MAINLY CIRRUS DROPPING ACROSS
THE AREA. PATCHY DENSE VALLEY FOG HAS FORMED IN VALLEY LOCATIONS AND
BASED ON RECENT ASOS AND AWOS OBS MAY BE A BIT MORE WIDESPREAD IN
PARTS OF THE CUMBERLAND VALLEY.
SO FAR AN SPS HAS BEEN ISSUED FOR THE DENSE FOG ACROSS THE SOUTHWEST
PART OF THE CWA. THIS WILL CONTINUE TO BE MONITORED OVER THE NEXT FEW
HOURS. FOG SHOULD GRADUALLY BEGIN TO LIFT AFTER SUNRISE AND DISSIPATE
BY AROUND 9 TO 10 AM.
OTHERWISE...A COUPLE OF WEAK SHORTWAVES ARE EXPECTED TO WORK ACROSS
THE OH VALLEY AND EASTERN KY THIS AFTERNOON AND THIS EVENING. AT THE
SAME TIME...THE BOUNDARY THAT SAGGED SOUTH INTO THE AREA WILL REMAIN
NEARLY STATIONARY OVER THE SOUTHWEST PART OF THE CWA...OR JUST TO
THE SOUTH AND WEST OF THAT REGION. DRIER DEWPOINTS ACROSS THE
NORTHERN AND EASTERN PART OF THE CWA MAY INITIALLY INHIBIT CONVECTION
A BIT...AS POSSIBLY THE MID LEVEL RIDGING TO OUR WEST. RECENT RUNS OF
THE RAP HAVE CONVECTION DEVELOPING NORTHWEST OF THE AREA IN THE
AFTERNOON AND APPROACHING THE AREA TOWARD SUNSET...BUT TENDS OF
WEAKEN IT LATE. THE 0Z NAM BRINGS SOME CONVECTION ACROSS THE REGION
AROUND SUNSET AND THE 0Z GFS IS RATHER SIMILAR. WITH THE BOUNDARY IN
THE VICINITY AND THE FACT THAT FORECAST SOUNDINGS GENERALLY DO NOT
INDICATE THAT THERE WILL BE SIGNIFICANT CAPPING...BUT FORCING WILL BE
RATHER WEAK OPTED TO CONTINUE WITH SLIGHT CHANCES FROM MID AFTERNOON
INTO THE EVENING HOURS.
THEREAFTER...A DIURNAL INCREASE IN CONVECTION IS ANTICIPATED
OVERNIGHT TONIGHT...AS THE MID LEVEL RIDGING BUILDS IN AND HEIGHTS
RISE FURTHER. PATCHY VALLEY FOG SHOULD AGAIN DEVELOP. THE MID LEVEL
RIDGING SHOULD GRADUALLY SHIFT EAST OF THE AREA ON MONDAY WITH A
SHORTWAVE TROUGH APPROACHING FROM THE WEST. THIS SHOULD ALSO LEAD TO
THE STATIONARY BOUNDARY LIFTING ACROSS THE AREA AS A WARM FRONT.
850 MB TEMPS SHOULD CLIMB TOWARD AT LEAST 18C. WIDESPREAD LOWER 90S
ARE EXPECTED FOR HIGHS OUTSIDE OF THE HIGHER TERRAIN. THE LIFTING WARM
FRONT AND HEIGHT FALLS LATE SHOULD COMBINE WITH DAYTIME HEATING FOR
SCATTERED CONVECTION...ESPECIALLY FROM MID AFTERNOON INTO THE EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 402 AM EDT SUN JUN 22 2014
THE PATTERN ACROSS THE CONUS CONTINUES A MAINLY ZONAL FLOW ACROSS
THE NORTHERN PART OF THE COUNTRY WITH WEAKENED RIDGING OVER THE
SOUTH. THIS IS MAINTAINED...AT LEAST FOR THE FIRST HALF OF THE
EXTENDED. ON TUESDAY...A SEEMINGLY WEAKER SHORTWAVE FROM RUN TO RUN
TRIES TO PUSH ACROSS THE LOWER GREAT LAKES AND AT THE
SURFACE...BRINGS A WEAK COLD FRONT ACROSS THE OH VALLEY. TOWARDS THE
LAST FEW DAYS OF THE EXTENDED...THE PATTERN BEGINS TO TRANSITION TO
A MORE AMPLIFIED PATTERN WITH DEVELOPING RIDGING ALONG THE MS RIVER
VALLEY AND TROUGHS DIGGING ALONG THE THE WEST COAST AND ALSO ALONG
THE EAST COAST. ONE SLIGHT CHANGE IN RECENT RUNS SHOWS A WAVE UNDER
CUTTING THE RIDGE AND DRIFTING INTO THE MID MS VALLEY AND INTO THE
TN VALLEY BY THE END OF THE EXTENDED.
OTHERWISE...THROUGH THE EXTENDED...A WARM...MOIST...AND UNSTABLE AIR
MASS REMAINS OVER EASTERN KENTUCKY. THIS WILL CONTINUE THE AFTERNOON
MAXIMUM CHANCE FOR PRECIP DWINDLING TO THE MINIMUM CHANCE OF PRECIP
INTO THE OVERNIGHT HOURS. THE ONE CHANCE OF DISRUPTING THIS TREND
WOULD BE THE ARRIVAL OF AN MCS THROUGH THE AREA...WHICH IS A
POSSIBILITY. OTHERWISE...DID NOT STRAY FROM THE MODEL ALL BLEND.
THIS PATTERN MAY BE COMING TO AN END BY THE END OF THE EXTENDED WITH
THE MODELS HINTING AT STRONG RIDGING BUILDING AND SHIFTING EAST OF
THE MS. OTHERWISE...HUMID...WARM...AND UNSTABLE DAYS ARE TO
CONTINUE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 705 AM EDT SUN JUN 22 2014
THE MOST IMPACTED AIRPORTS FROM INITIAL DENSE FOG WILL BE KLOZ AND
KSME. SOME MAY ALSO LIFT INTO SJS EARLY. THERE IS NO FOG NOW AT JKL
AND WE DO NOT EXPECT THIS TO CHANGE. WITH DAYTIME HEATING...INSTABILITY
WILL INCREASE AND THE THREAT OF AN ISOLATED SHRA OR TSRA AFTER
16Z...BUT PROBABILITIES AND CONFIDENCE IN THIS IS TOO LOW TO INCLUDE
ATTM. MORE VALLEY FOG SHOULD FORM LATE IN THE PERIOD...BUT THIS
SHOULD TEND TO NOT AFFECT THE TAF SITES UNLESS ONE TAKES A DIRECT HIT
FROM SHOWERS OR THUNDERSTORMS LATER TODAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR KYZ068-069-
079-080-083>088-115>118.
&&
$$
UPDATE...JP
SHORT TERM...JP
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1123 AM EDT SUN JUN 22 2014
.SYNOPSIS...
ISSUED AT 314 AM EDT SUN JUN 22 2014
NORTHERN MICHIGAN WILL REMAIN BETWEEN HIGH PRESSURE SINKING INTO
THE EASTERN GREAT LAKES TODAY...AND LOW PRESSURE OVER THE UPPER
MISSISSIPPI VALLEY. THERE WILL BE A FEW SHOWERS THIS MORNING...BUT A
BETTER SHOT OF SHOWERS AND THUNDERSTORMS...WILL ARRIVE LATER MONDAY
AND MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 1100 AM EDT SUN JUN 22 2014
AS REFERENCED IN THE EARLY MORNING DISCUSSION...ONE OF THE MAIN
FORECAST QUESTIONS FOR THIS AFTERNOON /IN AN OTHERWISE NEBULOUS
WEATHER REGIME/ IS WHETHER A FEW SHOWERS CAN POP THIS AFTERNOON
OVER INLAND AREAS OF NRN LOWER.
LARGE SCALE FORCING FOR ASCENT REMAINS WEAK...WITH H5 RIDGING
OVERHEAD AND LOWER LEVEL WEAK H8 THETA-E ADVECTION. MEANWHILE...
SURFACE PRESSURE PATTERN IS VERY WEAK/NONDESCRIPT. THIS WILL ALLOW
LAKE BREEZES TO EVOLVE WITH DAYTIME HEATING...WITH GENERAL
CONVERGENCE OVER INTERIOR /HIGHER TERRAIN/ AREAS. THOUGH 12Z APX
SOUNDING SHOWED A WEAK CAP NEAR H6 /BASED ON LIFTING A 76/56
PARCEL/ AM INCLINED TO INCLUDE ISOLATED LIGHT SHOWERS AFTER 18Z
FOR INTERIOR AREAS. DECISION BASED IN LARGE PART ON MORNING
VISIBLE SATELLITE TRENDS...WHICH SHOWS PERSISTENT LOW CLOUDS OVER
NW LOWER FROM TVC-FKS-MBL...MID CLOUDS OVER NE LOWER...AND
RELATIVELY SUNNY SKIES ALONG THE US-131/US-127 CORRIDORS. THIS
LATE MORNING DIFFERENTIAL HEATING REGIME /ALREADY SHOWN IN SURFACE
WINDS/ MAY BE JUST ENOUGH TO TIP SCALES IN FAVOR OF A FEW SHOWERS.
ONLY A 20 PERCENT CHANCE...AND ANY SHOWER THAT DEVELOPS SHOULD BE
BRIEF...THOUGH CELLS WILL BE SLOW MOVING.
OTHERWISE...A PARTLY SUNNY AFTERNOON IS EXPECTED WITH HIGHS AWAY
FROM THE BIG LAKES IN THE 70S.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 314 AM EDT SUN JUN 22 2014
...SOME SPOTTY SHOWERS THIS MORNING...
HIGH IMPACT WEATHER POTENTIAL: PATCHY FOG DEVELOPING AFTER MIDNIGHT
SUNDAY NIGHT/MONDAY MORNING.
PATTERN SUMMARY/IMPLICATIONS: VERY SIMILAR STORY TO WHAT WE
DISCUSSED 24 HOURS AGO WITH CLOSED LOW SITTING OVER
MANITOBA/SASKATCHEWAN WITH DOWNSTREAM RIDGING OVER MICHIGAN NORTH
INTO ONTARIO SQUEEZED AGAINST LARGER SCALE TROUGHING OVER EASTERN
CANADA. SHORTWAVES CONTINUE TO SHEAR OUT AS THEY RUN INTO THE
OVERHEAD RIDGE AXIS...WITH THE MOST RECENT WAVE OF DEEP MOISTURE NOW
BEGINNING TO PULL EAST OF THE STATE. DRILLING DOWN TO THE SURFACE
ALSO REVEALS STRONG SIMILARITY TO ONE DAY AGO WITH HIGH PRESSURE
ANCHORED OVER HUDSON BAY AND A SURFACE LOW BENEATH THE CLOSE FEATURE
OVER MANITOBA. BETWEEN THESE FEATURES...A PLUME OF DEEPER MOISTURE
REMAINS STALLED OVER NORTHERN MICHIGAN. WEAK POSITIVE THETAE
ADVECTION AT H8 CONTINUES TO FORCE SHRAS PRIMARILY OVER THE
NORTHEASTERN HALF OF THE CWA. GIVEN THE STAGNANT NATURE OF THE
PATTERN...FORECAST CHALLENGES WILL CONTINUE TO REVOLVE AROUND LIGHT
PRECIPITATION POTENTIAL WITH ASSOCIATED CLOUDS/IMPACTS ON
TEMPERATURES.
TODAY...
PRECIPITATION CHANCES: OVERHEAD H8 THETAE GRADIENT STALLS OVER
EASTERN CHIP/MACK SOUTH AND EAST ACROSS NORTHEAST LOWER THROUGH NOON
BEFORE BEING PUSHED NORTH AND EAST. WITH DEEP MOISTURE WANING /SEE
CURRENT WV IMAGERY/...EXPECT COVERAGE IN SHOWER ACTIVITY ASSOCIATED
WITH THIS GRADIENT TO WEAKEN...BUT LIKELY NOT QUIT THROUGH THE
MORNING HOURS...WARRANTING A CHANCE POP/SCATTERED WORDING HERE. AS
WE LOOK INTO THE AFTERNOON...FOCUS TURNS TO POPPING ANY DIURNAL
CONVECTION WITH A SOMEWHAT MOISTER LLEVEL AIRMASS THAN 24 HOURS
PREVIOUS. STILL THINK THE NAM IS TOO ROBUST WITH LLEVEL
MOISTURE...BUT EVEN THE FAR MORE CONSERVATIVE RAP ALLOWS FOR 500-750
JOULES OF MUCAPE DEVELOPMENT OVER THE HIGH TERRAIN OF INTERIOR
NORTHERN LOWER. QG FORCING FOR ASCENT IS NIL OVERHEAD WITH SLOWLY
BUILDING HEIGHTS ALOFT REQUIRING LAKE BREEZES/UPSLOPE CONVERGENCE TO
PUSH US TO CONVECTIVE INITIATION. HAVE TROUBLE BELIEVING WE CAN GET
AROUND MODEST CAPPING NEAR H7 PURELY WITH BOUNDARY LAYER PROCESSES.
THUS...WILL MAINTAIN GOING DRY FORECAST FOR THE AFTERNOON HOURS.
QPF: BASIN WIDE AMOUNTS VERY LIGHT...LESS THAN 0.05". ISOLATED
LOCATIONS COULD RECEIVE NEAR 0.20" GIVEN MODEST PWATS/WARM CLOUD
DEPTHS AND LIGHT STEERING FLOW.
TEMPERATURES: T8S NEAR +12C AT 00Z WITH CONTINUED SLOW WARMING
THROUGH TODAY SUGGESTS WE SHOULD BE ABLE TO BEST YESTERDAYS HIGHS
AND GUIDANCE CONSENSUS HANDLES THIS WELL...WITH MID/UPPER 70S INLAND
AND CLOSER TO 70 AT THE LAKE-BREEZE COOLED COASTS.
WINDS: CONTINUED LIGHT GRADIENT FAVORS ROBUST LAKE BREEZE
DEVELOPMENT THIS AFTERNOON.
TONIGHT...
PRECIPITATION CHANCES: WITH NO HELPFUL LLEVEL MOISTURE
ADVECTION...CHANCES WILL BE CONTINGENT ON AFTERNOON ACTIVITY
PERSISTING INTO THE EVENING. GIVEN THE CURRENT EXPECTATION THAT
WE/LL REMAIN SHOWER FREE THROUGH THE AFTERNOON...WILL MAINTAIN DRY
CONDITIONS THROUGH THE TONIGHT PERIOD AS WELL.
QPF: NIL.
TEMPERATURES: WILL STICK NEAR GUIDANCE CONSENSUS IN THE MID 50S AS
PARTLY CLOUDY SKIES SHOULD ALLOW FOR MODEST RADIATIONAL COOLING WITH
GEOSTROPHIC FLOW AT 1000MB NEAR 10KTS LIKELY STILL ALLOW MOST
LOCATIONS TO DECOUPLE.
WINDS: CALM OR LIGHT DRAINAGE FLOWS EXPECTED.
FOG: WITH MID/UPPER LEVEL MOISTURE BEGINNING TO PULL EAST...CAN SEE
SOME INCREASED FOG POTENTIAL AS LLEVEL FLOW GAINS A SOUTHWESTERLY
COMPONENT WITH CONTINUED WEAK LLEVEL MOISTURE ADVECTION AND ENOUGH
CLEARING FOR RADIATIONAL COOLING IN THE PRESENCE OF ELEVATED 2M
DEWPOINTS. WILL ADD PATCHY FOG TO THE FORECAST AFTER MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 314 AM EDT SUN JUN 22 2014
...SCATTERED THUNDERSTORMS MONDAY AND MONDAY NIGHT...
IMPACTS: MINIMAL. SEVERE STORMS STILL LOOK UNLIKELY.
SYNOPTIC PATTERN/EVOLUTION:
THE ENTIRE FORECAST PERIOD OF MONDAY THROUGH THE NEXT WEEKEND WILL
SEE A SHALLOW AND PROGRESSIVE MID LEVEL AMPLITUDE PATTERN THROUGH A
GOOD CHUNK OF THE WORK WEEK. THEN...HEIGHTS RISE OVER THE HEART OF
THE COUNTRY...INCLUDING THE WESTERN GREAT LAKES. THIS IS IN RESPONSE
TO TWO LARGE UPPER/CLOSED LOWS DROPPING INTO THE PAC NW/NEW ENGLAND.
AN INCREASINGLY MUGGIER AIR MASS MONDAY AND EARLY TUESDAY...AHEAD OF
AN APPROACHING AREA OF LOW PRESSURE AND PRECIPITATION...WILL GET
COOLED AND DRIED DOWN LATER TUESDAY THROUGH WEDNESDAY. TEMPERATURES
WILL START RISING BACK UP AGAIN FOR LATE IN THE WORK WEEK.
PRECIPITATION CHANCES AFTER EARLY TUESDAY DO NOT LOOK ALL THAT
FANTASTIC.
MON-TUES:
THE BEST ACTION RESIDES IN THIS TIME FRAME. SHALLOW RIDGING EXITS
EAST...WHILE AN ELONGATED UPPER TROUGH AXIS ACROSS ONTARIO BACKS
WINDS ALOFT WSW. SHORTWAVE ENERGY AND AN ASSOCIATED SFC LOW WILL
LIFT UP ACROSS NRN MICHIGAN. THIS LOW PRESSURE DOESN`T LOOK ALL THAT
IMPRESSIVE...BUT A WARM FRONT WILL EDGE UP THROUGH MUCH OF NRN
LOWER...WITH THE TRAILING COLD FRONT EXITING NEAR TUESDAY MORNING.
AS THE SFC LOW DEPARTS...ANOTHER COLD FRONT...ONE WITH MORE
REFRESHING AIR...WILL SLIDE SOUTHWARD THROUGH NRN MICHIGAN BY OVER
NIGHT TUESDAY NIGHT (UNCERTAINTY ON EXACT TIMING). COULD SEE SOME
SHOWERS POSSIBLY SNEAKING INTO A FEW SECTIONS OF NW LOWER MONDAY
MORNING...AND ALSO SOME POTENTIAL CONVECTIVE DEBRIS FROM FURTHER
WEST...BUT THE USING AN EXPECTED AVERAGE PARCEL OF 80/61 (DEW
POINT IS SOME QUESTION)...CAN POSSIBLY GLEAN 1000-1300 J/KG MONDAY
LATE AFTERNOON. RIGHT WITH THE WARM FRONTAL ARRIVAL. THE LOW TRACKS
OVER NRN MICHIGAN WITH MAINLY NRN LOWER SNEAKING INTO THE WARM
SECTOR FOR THE EVENING (TIMING ALSO IN SOME QUESTION). SHOWER AND
STORM CHANCES WILL BE GREATEST MONDAY NIGHT...AND ALTHOUGH NOTHING
OVERLY IMPRESSIVE...WILL HAVE TO WATCH THE DEVELOPMENTS SURROUNDING
WIND FIELDS AND INSTABILITY. THERE IS A TIGHTENING IN THE MID LEVEL
FLOW (40KTS)...AND IF THE INSTABILITY ABOVE CAN BE HAD...AND BEING
IN THE WARM SECTOR...WHILE EASTERN UPPER GETS GARDEN VARIETY SHOWERS
AND A FEW STORMS...NRN LOWER COULD SEE STRONGER CELLS. CELLS THAT
WILL BE IN A BETTER ENVIRONMENT FOR GUSTY WINDS/SMALLISH HAIL AND
THE POSSIBILITY OF A ROGUE TORNADO. THAT`S AN AWFUL LOT OF IF`S
THOUGH. AFTER THE LOW DEPARTS...AND SECONDARY COOL FRONT GETS
DROPPED THROUGH US...WITH MINIMAL FORCING...DIMINISHING MOISTURE AND
A TOTAL LACK OF INSTABILITY DUE TO MORE OF A COL AREA IN STORE FOR
US. HIGHS WELL INTO THE 70S MONDAY WILL START COOLING OFF...WITH
HIGHS TUESDAY IN THE UPPER 60S/70F IN EASTERN UPPER...AND UPPER 70S
NEARER SAGINAW BAY.
WEDNESDAY THROUGH NEXT WEEKEND:
AN EVEN COOLER DAY WEDNESDAY WITH HIGHS IN THE MAINLY IN THE 60S...A
FEW LOWER 70S...AS HIGH PRESSURE SLIPS INTO OUR NECK OF THE WOODS
FROM ONTARIO. SHOULD BE A BEAUTIFUL DAY. THERE ARE DEFINITE HINTS AT
SOME SHORTWAVE ACTIVITY TRACKING THROUGH US THURSDAY/THURSDAY NIGHT
FOR RAIN SHOWER CHANCES...BEFORE MID LEVEL HEIGHTS RISES BEGIN
FRIDAY AND CONTINUE INTO THE WEEKEND FOR A RETURN TO MIDDLE 70S TO
LOWER 80S TEMPS. EARLY HINTS ARE FOR NO PRECIPITATION NEXT WEEKEND
WITH ALL THE HEAT AND INSTABILITY RESIDING TO OUR WEST AND SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 106 AM EDT SUN JUN 22 2014
SUMMARY: A PLUME OF MID LEVEL MOISTURE WILL REMAIN ANCHORED ACROSS
NORTHERN MICHIGAN FOR MUCH OF THE UPCOMING TAF PERIOD WITH A FEW
SHOWERS FOR THE MORNING ON SUNDAY. THIS MOISTURE PLUME WILL LIFT
NORTH AND EAST OF THE REGION SUNDAY NIGHT WITH SOME POTENTIAL FOR
OVERNIGHT FOG DEVELOPMENT.
RESTRICTIONS: ONLY THREAT FOR RESTRICTIONS THROUGH THE PERIOD WILL
COME THROUGH DAYBREAK AT MBL/TVC. PRETTY MUCH A PERSISTENCE
FORECAST FROM ONE DAY AGO AT MBL/TVC WITH SOME DETERIORATION LIKELY
THROUGH DAYBREAK. THIS WILL LIKELY BRING A FEW PERIODS OF IFR CIGS
/AND POTENTIALLY VSBYS/ TO MBL...WITH OCCASIONAL MVFR CIGS /AND
POTENTIALLY VSBYS/ AT TVC.
ELSEWHERE...BKN VFR CLOUDINESS AND ISOLATED SHRAS WILL CONTINUE
BEFORE THINNING CLOUD COVER THIS EVENING. A FAVORABLE FOG SETUP
LOOKS POSSIBLE SUNDAY NIGHT...BUT EXPECT ANY SIGNIFICANT
RESTRICTIONS TO HOLD OFF UNTIL AFTER 06Z MONDAY.
WINDS: LIGHT WINDS TO CONTINUE THROUGH THE EARLY MORNING HOURS
BEFORE GIVING WAY TO LOCAL LAKE BREEZES IN THE AFTERNOON. WINDS WILL
AGAIN DIMINISH TO CALM/LIGHT DRAINAGE WINDS THIS EVENING.
LLWS: NO THREATS THIS CYCLE.
&&
.MARINE...
ISSUED AT 314 AM EDT SUN JUN 22 2014
SUMMARY: HIGH PRESSURE OVER HUDSON BAY WILL MOVE SOUTH AND EAST OFF
THE ATLANTIC COAST THROUGH MONDAY ALLOWING AN AREA OF LOW PRESSURE
TO MOVE INTO THE GREAT LAKES REGION FOR MONDAY NIGHT AND TUESDAY.
HIGH PRESSURE BUILDS INTO THE REGION BEHIND THIS LOW FOR WEDNESDAY
AND THURSDAY.
HEADLINES: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS
THROUGH MONDAY NIGHT. THERE IS SOME POTENTIAL FOR SMALL CRAFT LEVEL
WINDS UNDER NORTHWEST WINDS TUESDAY/TUESDAY NIGHT AS LOW PRESSURE
DEPARTS THE REGION TO THE EAST. AS LOW PRESSURE PULLS EAST OF THE
REGION HIGH PRESSURE BUILDS IN FOR THE WEDNESDAY-FRIDAY TIMEFRAME
WITH HEADLINE FREE CONDITIONS EXPECTED.
THUNDERSTORMS: CHANCES FOR STORMS INCREASE ON MONDAY WITH A PERIOD
OF THUNDERSTORMS LIKELY TUESDAY/TUESDAY NIGHT. WIDESPREAD SEVERE
THREAT IS LOW...BUT ISOLATED STRONG TO SEVERE STORMS ARE POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...SMITH
SYNOPSIS...SMD
SHORT TERM...ARNOTT
LONG TERM...SMD
AVIATION...ARNOTT
MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
748 AM EDT SUN JUN 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT SUN JUN 22 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER
CNTRL SASK/MANITOBA AND A DOWNSTREAM RIDGE FROM THE NRN LAKES TO
JAMES BAY. AT THE SFC...TROUGH EXTENDED INTO THE ERN DAKOTAS AND
CNTRL NEBRASKA FROM LOW PRES NEAR LAKE WINNIPEG WHILE HIGH PRES
PREVAILED TO THE EAST FROM SRN QUEBEC INTO THE NRN LAKES. A SHRTWV
TROUGH AHEAD OF THE MID LEVEL LOW SUPPORTED SOME SHRA/TSRA FROM NW
ONTARIO TO NEAR KELO. HOWEVER...THE STRONGER AND MORE WIDEPSREAD
CONVECTION WAS WELL TO THE SOUTH FROM ERN NEBRASKA INTO WRN IA WHERE
THE MORE FAVORABLE INSTABIILITY (MUCPAE TO NEAR 2K J/KG) AND
MOISTURE TRANSPORT WAS LOCATED. OTHERWISE...MAINLY LOW STRATUS
PREVAILED ACROSS MUCH OF WEST AND CENTRAL UPPER MI WHERE LOW LEVEL
MOISTURE REMAINS BELOW THE 925 MB INVERSION.
TODAY...EXPECT THAT THE SHRA/TSRA ASSOCIATED WITH THE MODEST FORCING
ASSOCIATED WITH THE NW ONTARIO SHRTWV WILL WEAKEN AS IT MOVES TOWARD
THE RIDGE. DAYTIME HEATING SHOULD BREAK UP THE LOWER CLOUDS SO THAT
AFTERNOON SUNSHINE WILL PUSH TEMPS INTO THE LOWER 80S INLAND WHILE
LAKE BREEZES LIMIT READINGS TO THE 60S NEAR THE GREAT LAKES. THE NAM
AND SEVERAL HIGHER RES MODELS SUGGEST THAT THERE WILL BE ENOUGH
INSTABILITY FOR SOME SHRA/TSRA OVER MAINLY THE WEST THIRD DURING THE
AFTERNOON. HOWEVER...SINCE MORE MODEST MLCAPE VALUES INTO THE
300-600 J/KG RANGE ARE EXPECTED AND LARGE SCALE FORCING IS NOT
FCST...CONFIDENCE FOR SHRA/TSRA DEVELOPMENT IS LOW AND ONLY SLIGHT
CHANCE POPS WERE INCLUDED.
TONIGHT...ANY CONVECTION THAT DEVELOPS DURING THE AFTERNOON WILL
DIMINISH DURING THE EVENING. HOWEVER...AS THE TROUGH AND FRONTAL
BOUNDARY EDGE TOWARD THE WRN CWA OVERNIGHT...SHRA/TSRA CHANCES WILL
INCREASE AS ADDITIONAL WEAK SHORTWAVES EMERGE FROM THE PLAINS. THERE
IS LESS CONFIDENCE IN THE EASTWARD EXTENT OF THE PCPN AS THE RIDGE
TO THE EAST LIMITS THE MOVEMENT OF THE MOISTURE AXIS TO THE EAST. IN
ADDITION...ANOTHER ROUND OF STRONGER CONVECTION IS MORE LIKELY OVER
NRN IA OR SRN MN INTO SRN WI THAT WOULD LIMIT MOISTURE TRANSPORT TO
THE NORTH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 509 AM EDT SUN JUN 22 2014
MONDAY CONTINUES TO LOOK LIKE A SHOWERY DAY ACROSS MUCH OF THE
WESTERN HALF OF UPPER MICHIGAN AS THE UPPER LOW OVER
MANITOBA/SASKATCHEWAN FINALLY OPENS UP AND SLOWLY MOVES EASTWARD.
MEANWHILE...A WEAK UPPER SHORT WAVE OVER THE CENTRAL PLAINS MOVES
TOWARD THE REGION. THESE TWO FEATURES WILL WILL ALLOW FOR WEAK LOW
PRESSURE TO DEVELOP OVER THE MID MS VLY AND MOVE TOWARD THE GREAT
LAKES. MOISTURE AND WARM ADVECTION AHEAD OF THE TROUGH WILL SPREAD
ACROSS THE AREA MONDAY AND BE SLOW TO MOVE OUT UNTIL THE LOW PASSES
BY TUE. EXPECT SHOWERS AND ISOLATED STORMS TO DEVELOP ACROSS THE
WESTERN U.P. MON MORNING THEN SLOWLY SPREAD EASTWARD DURING THE DAY
AS THE 850MB TROUGH AND ASSOCIATED MOISTURE CONVERGENCE MOVES EAST.
WITH THE COMBINATION OF THE FAVORABLE DYNAMICS FROM THE SHORT WAVE
ENERGY AS WELL AS HIGH MOISTURE CONTENT OF THE ATMOSPHERE
/PRECIPITABLE WATER VALUES AROUND 1.75 INCHES/...EXPECT A FEW AREAS
ACROSS THE WEST HALF TO SEE 0.50 TO 1.0 INCHES OF RAIN MONDAY UNDER
THE HEAVIEST AND MOST PERSISTENT SHOWER ACTIVITY. AS SUCH...WILL
KEEP LIKELY POPS ACROSS THE ENTIRE WESTERN HALF OF THE FORECAST AREA
ON MONDAY. FUTURE SHIFTS WILL LIKELY NEED TO RAISE POPS MORE...BUT
THERE IS STILL SOME UNCERTAINTY EXACTLY WHERE THE BEST RAIN WILL SET
UP.
AS THE LOW MOVES SOUTH OF THE AREA MONDAY NIGHT...THE COLD FRONT
ASSOCIATED WITH THE NORTHERN STREAM ENERGY WILL DIVE SOUTHWARD.
MOISTURE WILL PERSIST ACROSS MUCH OF THE EASTERN HALF OF UPPER
MICHIGAN MONDAY NIGHT COMBINED WITH SYNOPTIC FORCING FROM THE UPPER
TROUGH. AS SUCH...WILL MAINTAIN LIKELY POPS EAST FOR MONDAY NIGHT
TAPERING TO CHANCE POPS FOR THE WEST.
TUESDAY MAY END UP BEING A FAIRLY RAW DAY ACROSS AT LEAST THE
NORTHERN HALF OF UPPER MI WITH NORTHERLY FLOW BEHIND THE LOW
COMBINED WITH SCATTERED SHOWERS DUE TO THE CONTINUE 850MB BAROCLINIC
ZONE ACROSS THE AREA AND DEEP MOISTURE. WILL MAINTAIN CHANCE POPS
ACROSS THE ENTIRE AREA ALTHOUGH CLOSER TO LAKE SUPERIOR MAY SEE MORE
DRIZZLE THAN ANYTHING. AREAS CLOSE TO LAKE SUPERIOR MAY STRUGGLE TO
RISE OUT OF THE MID 50S ON TUESDAY ALTHOUGH INLAND AREAS WILL SEE
TEMPS RISE WELL INTO THE 60S.
FOR TUE NIGHT/WED...HIGH PRESSURE BUILDS ACROSS THE AREA LEADING TO
A DRY PERIOD THROUGH WED NIGHT. HIGH PRESSURE HANGS ON THRU THU
ALTHOUGH THE ECMWF AND GFS BOTH SUGGEST ANOTHER SHORT WAVE MOVING
INTO THE UPPER LAKES DURING THE DAY WHICH MAY ALLOW FOR SHOWERS AND
ISOLATED STORMS DURING THE AFTERNOON. UPPER RIDGING FINALLY BUILDS
IN FOR THE WEEKEND WHICH MEANS TEMPERATURES RISING TO ABOVE NORMAL.
MAY BE A CHANCE FOR RAIN FRI NIGHT INTO SATURDAY AS WEAK WARM
ADVECTION DEVELOPS...BUT LATEST ECMWF SUGGESTS THAT THE RAIN CHANCES
WILL HOLD OFF UNTIL SAT NIGHT/SUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 748 AM EDT SUN JUN 22 2014
THE COMBINATION OF DAYTIME HEATING AND SOME LOW LEVEL DRYING WILL
ALLOW THE FOG/STRATUS TO BURN OFF AND CONDITIONS TO TRANSITION
GRADUALLY TO VFR BY NOON. MORE FOG AND LOW CLOUDS COULD ROLL IN OFF
LAKE SUPERIOR THIS EVENING AT CMX. A FEW SHOWERS ARE POSSIBLE
OVERNIGHT AT CMX AND IWD BUT ARE NOT EXPECTED TO REDUCE CONDITIONS
BELOW VFR. A THUNDERSTORMS IS ALSO POSSIBLE BUT CONFIDENCE IS TOO
LOW TO INCLUDE MENTION IN THE TAF.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SUN JUN 22 2014
DENSE FOG WILL CONTINUE TO BE THE MAIN CONCERN ACROSS WEST AND
CENTRAL LAKE SUPERIOR. LINGERING LOW LEVEL MOISTURE WITH PERSISTENT
LIGHT E OR SE LOW LEVEL FLOW WILL ALLOW FOR DENSE FOG WILL HELP TO
MAINTAIN THE FOG OR LOW STRATUS TODAY. THERE MAY BE ENOUGH DRY AIR
MOVING IN THIS AFTERNOON TO MIX OUT THE FOG BUT THERE IS THE
POSSIBILITY THAT AN EXTENSION OF THE DENSE FOG ADVISORY MAY BE
NEEDED. WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH THIS
FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING FOR
LSZ162-240>248-263>265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
606 AM CDT Sun Jun 22 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 336 AM CDT Sun Jun 22 2014
Once again the main forecast issue is thunderstorm chances. The
only ongoing precipitation early this morning is a shrinking area
of showers in Pike Co MO. This originated from a NW-SE cluster of
thunderstorms which occurred just north of Mexico in response to
lift via a weak westerly LLJ along the cool side of a large scale
outflow boundary. That boundary remains somewhat identifiable
from far southern IL into central/NW MO. While there is no clear
cut model solution, there are suggestions by the deterministic
guidance which are supported by recent runs of the HRRR and the
4km NSSL WRF that this confluent zone from central through
southeast MO will be the region of scattered thunderstorm
development beginning near midday, with activity shifting east thru
the afternoon. There may be a region of somewhat greater coverage
and organization across northeast Missouri and west central IL
resulting from an eastward migrating vort max which is now present
in the central Plains. Highs once again look seasonable in the
upper 80s to lower 90s.
Glass
.LONG TERM: (Tonight through Saturday)
Issued at 336 AM CDT Sun Jun 22 2014
The greatest threat of thunderstorms tonight should also reside
across the northern portion of the CWA where the consensus of the
model QPFs have the highest coverage. This appears reasonable as a cold
front will be pushing into IA and NW MO in association with a much
better defined slowly progressive short wave trof and attendant
vort maxes. Strengthening and veering wind fields and a stronger
veering WSW LLJ should result in good eastward progression of
organized convection. The cold front will move slowly across the
area Monday and Monday night and should be accompanied by fairly
widespread showers and thunderstorms. The models vary on how far
south the front will push on Tuesday with the NAM showing the
least progression only into southern IL and southern MO while the
GFS and SREF push the front into AR. Eventually the front will
retreat back northward and be the focus for additional showers and
thunderstorms through the later half of the upcoming week. The NAM
is just about 12-24h faster thru its 84h forecast ending Wednesday.
Glass
&&
.AVIATION: (For the 12z TAFs through 12z Monday Morning)
Issued at 557 AM CDT Sun Jun 22 2014
A hot and humid air mass with plenty of leftover outflow
boundaries will support yet another day of low-predictability
scattered afternoon/evening thunderstorms. Widespread
precipitation is expected just beyond the end of the 24hr TAF
period.
Specifics for KSTL: A hot and humid air mass with plenty of
leftover outflow boundaries will support yet another day of
low-predictability scattered afternoon/evening thunderstorms.
Widespread precipitation is expected near the end of the 30hr TAF
period (primarily after 23/12z) due to the approach of a cold
front and an upper level disturbance.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1049 AM CDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 1048 AM CDT SUN JUN 22 2014
THE FORECAST WAS UPDATED FOR PRECIPITATION AND WEATHER FOR TODAY.
PARTLY TO MOSTLY SUNNY SKIES ARE CURRENTLY BEING OBSERVED. THE
RAIN OVER THE NORTHEAST PART OF THE FORECAST AREA HAS MOVED EAST
OF THE AREA. WITH THE EXCEPTION OF A FEW WEAK RADAR ECHOES THAT
HAVE MOVED ACROSS NORTHERN SHERIDAN COUNTY...THE SHOWERS AND
ISOLATED THUNDERSTORMS OVER SOUTH DAKOTA HAVE STAYED NORTH OF THE
FORECAST AREA. THE HRRR HAS BEEN HANDLING THIS ACTIVITY FAIRLY
WELL...HAVING IT MOVE STRAIGHT EAST RATHER THAN DIPPING SOUTH AS
HAD BEEN PREVIOUSLY FORECAST. DUE TO THES TRENDS...CHANCES HAVE
BEEN REMOVED FOR MOST PLACES THROUGH THE MORNING HOURS. THERE IS
SOME INSTABILITY ACROSS THE AREA...IN THE ORDER OF 500-1500 J/KG
SB CAPE ACCORDING TO THE SPC MESOANALYST PAGE AT 1530Z. THIS
SHOULD STAY FAIRLY STABLE THROUGH THE AFTERNOON. THERE WILL BE A
LACK OF FORCING THOUGH THIS AFTERNOON AS SHORTWAVES ARE LOOKING TO
MOVE ACROSS SOUTH DAKOTA...AND THEN OUT OF COLORADO AND INTO
KANSAS LATER IN THE DAY. FEEL THAT THERE MAY BE SOME ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS...BUT WITH THE LACK OF FORCING
ACTIVITY SHOULDN/T BE WIDESPREAD SO HAVE LOWERED THE COVERAGE OF
STORMS IN THE FORECAST FOR THIS AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUN 22 2014
OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY
RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST
MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING
IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE
TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE
HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO
BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT
NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE
AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 22 2014
MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE
EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD
RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING
THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR
DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED
FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS
THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS
THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT
UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY
RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT
PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK
SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT
WEEKEND.
FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED
FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK
UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR
A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE
HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS
IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE
HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON
TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA.
WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR
STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY
WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE
OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS
LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR
COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY
BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA
TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE
POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT
IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD
30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE
THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS
SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE
STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY
NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR
MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE
FROM THE PROCEDURE ATTM.
TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT
WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON
MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER
90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS
DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO
WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED
FORECAST PERIODS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 619 AM CDT SUN JUN 22 2014
WITH THE EXCEPTION OF SCATTERED TSTMS...VFR IS EXPECTED MOST
AREAS TODAY AND TONIGHT.
THE DISTURBANCE OVER NERN WY MOVES THROUGH WRN/NCNTL NEB TODAY AND EXITS
THIS EVENING. THE MODEL CONSENSUS SUGGESTS TSTM ACTIVITY WOULD
EXPAND IN COVERAGE ACROSS THE SANDHILLS THIS AFTN AND CONTINUE
SOUTH AND EAST THROUGH THE FCST AREA BEFORE EXITING THIS EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BROOKS
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
624 AM CDT SUN JUN 22 2014
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 234 AM CDT SUN JUN 22 2014
MOSAIC RADAR IMAGERY THIS MORNING SHOWING TWO DISTINCT CLUSTER OF
TSTMS...ONE OVER ERN SD ASSOCIATED WITH A SEWD BOUND COLD FRONT/MID
LYR UPGLIDE. OTHER ONE WAS SITUATED ALONG INVERTED SFC TROF/THERMAL
BNDRY EXTENDING FROM NW KS INTO S-CNTRL NEB WITHIN AREA OF MID LYR
QG FORCING. THE LATEST HRRR IS ADVERTISING THE NRN ACTIVITY WILL
QUICKLY DIMINISH THE NEXT COUPLE HOURS WHILE SW TSTMS BECOME
DOMINATE FEATURE AND EXPAND INTO THE CWA EARLY THIS MORNING. FOR
TODAY/TONIGHT...EXPECT COMBINATION OF DAYTIME HEATING AND MOISTURE RICH
ENVIRONMENT EXPECT WILL ALLOW FOR QUICK DESTABILIZATION AND TSTM
REDEVELOPMENT ALONG AXIS OF BNDRY LYR THETA-E CONVG WITH APPROACH
OF FRONTAL BNDRY FROM THE NORTH. AS FOR SEVERE TSTM
POTENTIAL...BOTH NAM AND GFS ARE IN PRETTY GOOD AGREEMENT SHOWING
HIGH BUOYANCY BUT RELATIVELY WEAK VERTICAL WIND SHEAR THUS
FAVORING MULTISTORM DEVELOPMENT. NEVERTHELESS...CANNOT TOTALLY
DISCOUNT A FEW SEVERE STORMS LATE AFTN/EARLY EVENING. PCPN
ACTIVITY WILL BE COMING TO AN END THEN MONDAY MORNING AS DRY
AIRMASS/SUBSIDENCE BUILDS IN FROM THE NORTH. TUES/TUES
NIGHT...MODELS LAY QPF WEST OF THE CWA WITHIN AREA OF PRONOUNCED
MID LYR AGEOSTROPHIC LIFT. PCPN ACTIVITY THEN PROGGED TO EXPAND
QUICKLY EWD INTO THE CWA...THUS WILL LEAVE GOING POPS IN PLACE.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 234 AM CDT SUN JUN 22 2014
GOING FCST HAS PCPN CHANCES PRETTY MUCH IN PLACE THRU THE EXTENDED
PDS. AT THIS POINT GIVEN LATEST MODELS SUPPORT GOING POPS...SEE
LITTLE REASON FOR MAKING ANY MAJOR MODIFICATIONS. ZONAL FLOW EARLY
ON IN THE FCST PD BECOMES MORE AMPLIFIED IN RESPONSE TO A DEEP
UPSTREAM UPPER TROF MOVING ONTO THE WEST COAST THURSDAY BEFORE LARGE
SCALE BEGINS SMOOTHING OUT TO NEAR ZONAL NEXT WEEKEND. PCPN CHANCE
PRETTY MUCH REVOLVING AROUND LIFTING WARM FRONT FOLLOWED BY A COLD
FRONT ADVANCING THRU THE CNTRL PLAINS. THERMAL ADVECTION WITH THESE
BOUNDARIES LOOKS RELATIVELY WEAK SO NOT MUCH DEVIATION FROM NEAR
NORMAL TEMPS ANTICIPATED.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 620 AM CDT SUN JUN 22 2014
MORNING THUNDERSTORMS HAVE PASSED BY KOFK/KLNK...AND SHOULD PASS
BY KOMA IN THE NEXT HOUR OR SO. SHOWERS SHOULD LINGER FOR A
COUPLE OF HOURS AFTER THAT...WITH ALL ACTIVITY MOVING OUT BY MID-
MORNING. WINDS WILL BE VARIABLE BUT MAINLY 10KT OR LESS FROM
MORNING THROUGH AFTERNOON. SHOWERS/STORMS MAY REDEVELOP IN NEB
LATER TODAY...BUT CONFIDENCE IS LOW IN DEVELOPMENT AND POTENTIAL
PLACEMENT...AND HAVE LEFT MENTION OUT OF TAF SITES. WINDS WILL
BECOME NORTHWESTERLY AT ALL SITES BETWEEN 00-06Z AS COLD FRONT
SAGS THROUGH TAF SITES...WITH CLEARING BEHIND THE FRONT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...MAYES
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
622 AM CDT SUN JUN 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUN 22 2014
OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY
RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST
MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING
IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE
TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE
HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO
BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT
NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE
AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 22 2014
MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE
EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD
RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING
THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR
DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED
FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS
THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS
THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT
UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY
RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT
PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK
SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT
WEEKEND.
FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED
FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK
UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR
A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE
HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS
IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE
HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON
TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA.
WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR
STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY
WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE
OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS
LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR
COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY
BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA
TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE
POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT
IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD
30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE
THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS
SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE
STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY
NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR
MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE
FROM THE PROCEDURE ATTM.
TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT
WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON
MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER
90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS
DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO
WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED
FORECAST PERIODS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 619 AM CDT SUN JUN 22 2014
WITH THE EXCEPTION OF SCATTERED TSTMS...VFR IS EXPECTED MOST
AREAS TODAY AND TONIGHT.
THE DISTURBANCE OVER NERN WY MOVES THROUGH WRN/NCNTL NEB TODAY AND EXITS
THIS EVENING. THE MODEL CONSENSUS SUGGESTS TSTM ACTIVITY WOULD
EXPAND IN COVERAGE ACROSS THE SANDHILLS THIS AFTN AND CONTINUE
SOUTH AND EAST THROUGH THE FCST AREA BEFORE EXITING THIS EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1046 AM CDT SUN JUN 22 2014
.UPDATE...
MIDMORNING GOES IR IMAGERY SHOWED A COUPLE OF MCS THIS MORNING...
OVER EASTER NE AND IA AND ANOTHER OVER NORTH TX. NEITHER MCS WAS
UPSTREAM OF THE MIDSOUTH...AND THE TX MCS HAD REARWARD PROPAGATION
COMPONENT. NEARER TO THE MIDSOUTH...SOME MIDLEVEL CLOUD COOLING
WAS NOTED ON IR OVER CENTRAL AND NORTH MS...PERHAPS AN INDICATION OF
ENHANCED MIDLEVEL LIFT FROM A WEAK 250MB JET STREAK OVER THE
ARKLAMISS REGION.
TODAY/S RAIN CHANCES FOR THE MIDSOUTH APPEAR A LITTLE MORE LIMITED
THAN SATURDAY...GIVEN THE LACK OF A DISTINCT MCS OR MIDLEVEL
SHORTWAVE TROF. 13Z HRRR MODEL DEPICTED AFTERNOON THUNDERSTORM
COVERAGE TO BE ISOLATED AT BEST. HOWEVER...12Z NAM BUFR SOUNDINGS
SHOW THE BOUNDARY LAYER UNCAPPED BY 18Z...WITH SURFACE BASED CAPE
IN EXCESS OF 2000 J/KG AREAWIDE.
IN THE ABSENCE OF A SHORTWAVE TROF OR MCV...MESOSCALE PROCESSES
/DIFFERENTIAL HEATING...OUTFLOW BOUNDARY INTERACTIONS/ WILL
LIKELY DETERMINE WHERE AND IF THUNDERSTORMS INITIATE AND SUBSEQUENTLY
EVOLVE.
MOST RECENT FORECAST UPDATED INCLUDED MINOR ADJUSTMENTS TO TIMING
OF POPS AND TO EDGE AFTERNOON TEMPS UP A BIT NORTH AND EAST OF THE
MEMPHIS METRO.
PWB
&&
.PREV DISCUSSION... /ISSUED 633 AM CDT SUN JUN 22 2014/
DISCUSSION...
UPDATED FOR THE 12Z AVIATION DISCUSSION
PREV DISCUSSION... /ISSUED 352 AM CDT SUN JUN 22 2014/
DISCUSSION...
THE LONGEST DAY OF THE YEAR HAS COME TO AN END AND ITS ANOTHER
QUIET SUMMER NIGHT ACROSS THE MIDSOUTH. TEMPERATURES HAVE FALLEN
INTO THE UPPER 60S IN THE COOLEST LOCATIONS ACROSS THE MIDSOUTH
WITH MOST AREAS IN THE LOW TO MIDDLE 70S. MORNING LOWS SHOULD BE
IN THE UPPER 60S TO NEAR 70 DEGREES AREA WIDE. PATCHY FOG HAS
DEVELOPED...AND VISIBILITY HAS DROPPED AS LOW AS 1/4 MILE IN
ALCORN COUNTY MISSISSIPPI...BUT THAT IS THE EXCEPTION. MOST AREAS
ARE ONLY EXPERIENCING SLIGHT REDUCTIONS TO VISIBILITY IF ANY. WILL
MONITOR ADDITIONAL FOG DEVELOPMENT...BUT DO NOT ANTICIPATE THE
NEED FOR ANY KIND OF ADVISORY.
WE WILL LIKELY SEE ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
DEVELOP THIS AFTERNOON. WIDESPREAD SEVERE STORMS ARE NOT
EXPECTED...BUT ISOLATED SEVERE STORMS AS WELL AS NUMEROUS STRONG
STORMS ARE POSSIBLE. THE MAIN THREAT FROM ANY STRONG TO SEVERE
STORMS WILL BE WINDS...MAINLY IN THE FORM OF WET MICROBURSTS.
GUIDANCE SUGGESTS STORMS WILL DEVELOP QUICKLY AFTER SUNRISE. THE
GFS SHOWS A FAIRLY DECENT VORT MAX TRACKING OUT OF SOUTHERN
ARKANSAS INTO CENTRAL MISSISSIPPI THIS AFTERNOON...AND THERE IS
SOME INDICATION ON SATELLITE OF THIS FEATURE IN SOUTHERN ARKANSAS
RIGHT NOW. THIS MAY ENHANCE STORMS ACROSS NORTH MISSISSIPPI...BUT
FOR THE MOST PART WE ARE NOT TARGETING ANY SPECIFIC PORTION OF THE
MIDSOUTH FOR ENHANCED COVERAGE OR STRENGTH OF STORMS. DEW POINTS
IN THE LOW TO MIDDLE 70S WILL HELP TO PRODUCE A VERY UNSTABLE
ENVIRONMENT FEATURING CAPE VALUES INTO THE 2500-3000 J/KG RANGE
THIS AFTERNOON AND LI`S BELOW -7C. MOISTURE LEVELS ALOFT ARE ALSO
HIGH...BOTH LITTLE ROCK AND NASHVILLE AFTERNOON SOUNDINGS HAD PW
VALUES AROUND 1.5 INCHES. AS A RESULT...HEAVY RAINFALL IS LIKELY.
STORM MOTION WILL BE SLOW...LIKELY DRIFTING EAST TO SOUTHEAST SO
ISOLATED FLOODING PROBLEMS ARE POSSIBLE.
ENHANCED RAIN CHANCES WILL REMAIN IN THE FORECAST THROUGH MIDWEEK
WITH THE GREATEST CHANCES MONDAY AFTERNOON THROUGH TUESDAY
AFTERNOON AS A SEASONABLY STRONG SHORTWAVE TROUGH SHIFTS OUT OF
THE CENTRAL/SOUTHERN PLAINS ACROSS THE MISSISSIPPI RIVER VALLEY.
ONCE AGAIN...NO WIDESPREAD SEVERE STORMS ARE EXPECTED...BUT ANY STORMS
ARE LIKELY TO BECOME STRONG WITH OUR CURRENT ATMOSPHERIC
CONDITIONS AND ISOLATED SEVERE STORMS ARE POSSIBLE. DAMAGING WIND
IS THE MOST LIKELY THREAT. HIGH TEMPERATURES SHOULD BE KEPT DOWN A
BIT ESPECIALLY MONDAY AND TUESDAY. HIGHS MAY EVEN REMAIN IN THE
LOW 80S IF THUNDERS STORMS AND CLOUDS ARE NUMEROUS.
AFTER MIDWEEK...AS THE SHORTWAVE SHIFTS EAST OF THE MIDSOUTH A
WEAK RIDGE AND SURFACE HIGH PRESSURE WILL TRY TO REASSERT ITS
INFLUENCE ACROSS THE MIDSOUTH. EXPECT LESS RAIN THURSDAY INTO THE
WEEKEND AND SLIGHTLY WARMER TEMPERATURES. GUIDANCE IS NOT IN
PERFECT AGREEMENT WITH THIS SOLUTION. THE ECMWF FEATURES A
STRONGER RIDGE CENTERED FARTHER NORTH AND WEST WHICH WOULD RESULT
IN AN EVEN WARMER AND DRIER FORECAST FRIDAY THROUGH THE WEEKEND.
FOR NOW WILL PLAY THE MIDDLE OF THE ROAD...HOLDING ONTO SLIGHT
CHANCE TO LOW CHANCE POPS DURING THE END OF THE FORECAST PERIOD
AND NEAR NORMAL TEMPERATURES.
30
&&
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS SHOULD PERSIST FOR MUCH OF THE FORECAST PERIOD.
SOME SCATTERED THUNDERSTORMS WILL MOVE ACROSS THE FORECAST AREA
MAINLY DURING THE AFTERNOON HOURS. WINDS WILL BE FAIRLY LIGHT AND
MAINLY FROM THE WEST FOR MUCH OF THE FORECAST PERIOD.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1030 AM CDT SUN JUN 22 2014
.UPDATE...
SEE MORNING UPDATE.
&&
.DISCUSSION...
AT 9 AM...SFC HIGH PRESSURE WAS LOCATED OVER SW LOUISIANA AND LOW
PRESSURE WAS OVER WESTERN KANSAS. VIS SATELLITE SHOWED EXTENSIVE
CLOUD COVER OVER MOST OF THE STATE WITH SOME BREAKS IN THE CLOUDS
OVER SE TX. 12Z SOUNDINGS SHOW PW VALUES AROUND 1.70 INCHES...
CONVECTIVE TEMPS BETWEEN 86 AND 90 DEGREES...NO CAPPING AND WITH A
LAYER OF DRY AIR BETWEEN 800 MB AND 600 MB. AT 850 MB...A SWATH OF
DEEP MOISTURE EXTENDED ACROSS CENTRAL TEXAS EXTENDING FROM DODGE
CITY KANSAS TO NORTHERN MEXICO. AN 850 MB RIDGE WAS OVER THE
NORTHERN GULF AND EXTENDED NORTH INTO CENTRAL ARKANSAS. AT 700
MB...DEEPER MSTR AND A WEAK 700 MB TROUGH AXIS EXTENDED FROM NE
TEXAS TO THE BIG BEND. AT 250 MB...A WEAK HIGH WAS OVER NORTHERN
MEXICO WITH A SPEED MAX OVER NORTH CENTRAL MEXICO. A WEAK S/WV
EXTENDED FROM SOUTH CENTRAL KANSAS TO NE TEXAS.
BOTH THE ECMWF AND THE GFS SHOW SE TX IN A WEAK LFQ THIS AFTN AND
THIS IS SUPPORTED BY THE 12Z 250 MB ANALYSIS. CONSIDERING THE
LIFT PROVIDED BY THE SPEED MAX...A WEAK SPLIT IN THE UPPER JET...
DIFFERENTIAL HEATING AND WEAK PVA...FEEL CONVECTIVE POTENTIAL WILL
BE INCREASING THIS AFTN. THE RAP 13 AND HRRR SHOW THE BEST
POTENTIAL OVER THE NE ZONES THIS AFTN SO HAVE RAISED POPS OVER THE
NE. ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE
HEAVY RAIN AS STORM MOTION WILL BE ON THE SLOW SIDE. CLOUDS WILL
WREAK HAVOC WITH MAX TEMPS BUT ANY BREAK IN THE CLOUD COVER WILL
ALLOW TEMPS TO WARM QUICKLY. LEFT TEMP FCST AS IS. OVERALL...ONLY
MINOR CHANGES AS PREV FCST HAD THINGS WELL IN HAND. 43
&&
.PREV DISCUSSION... /ISSUED 626 AM CDT SUN JUN 22 2014/
DISCUSSION...
SEE AVIATION.
AVIATION...
SEEING A BAND OF SHRA APPROACHING NW AREAS OF SE TX THIS MORNING
WHICH WILL AFFECT CLL 12-14Z. BY MID MORNING EXPECT TO SEE SCT
SHRA ACROSS MOST OF THE AREA. EXPECT ISOLATED/SCATTERED TSRA
AROUND THIS AFTERNOON...ESPECIALLY IN THE VICINITY OF A WEAK SEA
BREEZE. AMPLE HIGH CLOUDS WILL CONTINUE THROUGH THE DAY. 33
PREV DISCUSSION... /ISSUED 440 AM CDT SUN JUN 22 2014/
DISCUSSION...
TX AREA RADAR SHOWS QUITE A BIT OF SHOWER ACTIVITY OVER N TX
WHICH MAY BE THE RESULT OF A SHORTWAVE TROUGH AND OLD MCV THAT IS
SHEARING OUT OVER THE AREA. CLOUD COVER HAS HELD TEMPS IN THE MID
70S FOR MUCH OF THE AREA THIS MORNING SO NOT QUITE AS COOL AS
YESTERDAY. BASED ON 00Z SOUNDINGS LCH AND CRP ARE SHOWING PRECIP
WATER VALUES OF 1.5 TO 1.7 INCHES RESPECTIVELY. THINK PRECIP WATER
VALUES WILL BE CLOSER TO 1.7 INCHES OVER MUCH OF THE AREA TODAY.
THE 00Z 500MB ANALYSIS SHOWS 589/590 DM HEIGHTS ALONG THE NW GULF
COAST SO THINK RIDGE IS MOVING MORE INTO THE GULF TOWARDS THE BAY
OF CAMPECHE. HEIGHTS HAVE COME DOWN SOME WHICH SHOULD SUPPORT MORE
SHOWER AND THUNDERSTORM ACTIVITY TODAY ESPECIALLY WITH HIGHER
MOISTURE. FORECAST WILL GO WITH MAINLY 30/40 POPS TODAY. LOOKING
AT STORM TOTAL ACCUM RAINFALL FROM YESTERDAY...FEW STRONGER STORMS
COULD EASILY DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME.
MAIN IMPACT WILL BE LOCALIZED STREET FLOODING WITH THE HEAVY
RAINFALL AND GUSTY WINDS FROM OUTFLOWS.
BY MONDAY BROAD TROUGHING BECOMES MORE ESTABLISHED OVER TX AND
REALLY NO HINT OF ANY RIDGING. MODELS OUTPUT MEAGER RAINFALL
AMOUNTS AND KEEP POPS LOW SO WILL ONLY GO WITH 20/30 POPS. IT
LOOKS LIKE PRECIP WATER VALUES MAY DROP CLOSER TO 1.5 INCHES ON
MONDAY BEFORE SURGING BACK UP ON TUE/WED. TUE LOOK FOR HIGHER
MOISTURE VALUES AND TROUGHING BECOMING MORE PRONOUNCED. SHORTWAVE
NOW OVER CALIFORNIA WILL HAVE MADE ITS WAY ACROSS THE S ROCKIES
INTO THE S PLAINS BY THIS TIME. THIS MAY HELP BRING HEIGHTS DOWN
BELOW 588 DM AT 500MB. PRECIP WATER VALUES MAY BE APPROACHING 2
INCHES BY WED PER NAM/GFS SOLUTIONS. DECIDED TO GO A BIT HIGHER
WITH POPS ON TUE INTO WED. WED LOOKS TO BE MORE WET BUT WILL KEEP
POPS AT 50 FOR NOW. QUITE POSSIBLE TO HAVE SCATTERED TO WIDESPREAD
CONVECTION EACH DAY FROM WEDNESDAY THROUGH THE END OF THE WEEK.
BEST CHANCES OF RAIN LOOK TO BE WED/THUR/FRI WITH BROAD TROUGHING
ALOFT AND PRECIP WATER VALUES NEAR 1.9 TO 2 INCHES EACH DAY. IT
WILL NOT TAKE MUCH HEATING FOR CONVECTION TO DEVELOP EACH DAY.
WITH THAT MUCH MOISTURE...MAIN CONCERN WILL BE LOCALLY HEAVY
RAINFALL RESULTING IN LOCALIZED FLOODING. QUITE POSSIBLE THAT
URBAN AREAS COULD SEE STREET FLOODING AS A RESULT. BAYOUS COULD
RESPOND WITH RAPID RISES AS WELL. IMPACTS COULD BE MADE WORSE BY
ANY TRAINING STORMS BUT TOO EARLY TO DETERMINE THOSE KINDS OF
DETAILS JUST YET.
OVERALL EXPECT TEMPERATURES TO BE IMPACTED BY CLOUD COVER AND
CONVECTION. STILL SUMMER TIME SO IT DOES NOT TAKE MUCH TO REACH
LOW 90S FOR MAX TEMPS. THIS ALSO MEANS CONVECTIVE TEMPS SHOULD BE
REACHED AND TRIGGER CONVECTION. FORECAST WILL KEEP TEMPS IN THE
90-92F RANGE BUT COULD SEE UPPER 80S FOR HIGHS SHOULD SCATTERED TO
WIDESPREAD CONVECTION DEVELOP. LOW TEMPS IN THE LOW/MID 70S LOOK
ON TRACK AS WELL ESPECIALLY WITH ANY RAIN COOLED AIR THAT
DEVELOPS. STILL NOT BAD HAVING TEMPS NEAR NORMAL FOR THE END OF
JUNE.
39
MARINE...
PERSISTENT ONSHORE FLOW WILL CONTINUE THROUGH THE WEEK. SOUTHERLY
WINDS WILL APPROACH SCEC CRITERIA WELL OFFSHORE TONIGHT AND MONDAY
NIGHT...BUT WILL LIKELY STAY JUST BELOW. BY TUESDAY NIGHT THE
PRESSURE GRADIENT TIGHTENS AND WE WILL LIKELY SEE 15 TO 20 KT
ONSHORE WINDS OFFSHORE. BY MID-WEEK WINDS WILL INCREASE FURTHER
AND SEAS WILL BUILD. BUMPED WINDS AND SEAS WED-FRI TO REFLECT THE
CURRENT GFS...AND SCA CONDITIONS ARE POSSIBLE LATE THIS WEEK
OFFSHORE. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 90 75 91 76 90 / 40 20 20 20 40
HOUSTON (IAH) 90 76 92 77 90 / 40 20 20 20 40
GALVESTON (GLS) 87 80 88 80 87 / 20 10 20 20 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
643 AM CDT SUN JUN 22 2014
.AVIATION...ISOLATED TO SCATTERED LOW TOP SHOWERS MOVING E-NE ACROSS
SOUTH CENTRAL TEXAS THIS MORNING. ANY OF THE TERMINAL SITES MIGHT SEE
A PASSING SHOWER BUT IMPACTS WILL LIMITED TO MVFR CEILINGS BETWEEN
1500-2500 FEET. MULTI-LAYERED CLOUDS TO REMAIN ACROSS THE AREA
WITH THE LOWER CLOUDS LIFTING AND BREAKING UP AROUND OR SHORTLY AFTER
16Z. ISOLATED SHOWERS AND THUNDERSTORMS TO REDEVELOP THIS
AFTERNOON BUT CHANCE REMAINS LOW FOR ANY ONE TO PASS ACROSS
TERMINALS SO WILL LEAVE OUT OF TAFS AT THIS TIME. LOW LEVEL
INVERSION OVERNIGHT WITH MVFR CIGS EXPECTED TO RETURN ALONG THE I
35 CORRIDOR THEN SPREAD WEST. A LIGHT TO MODERATE PRESSURE GRADIENT
TO MAINTAIN AND SOUTHEAST TO SOUTH FLOW AT SPEEDS UNDER 20 KNOTS.
&&
.PREV DISCUSSION... /ISSUED 347 AM CDT SUN JUN 22 2014/
SHORT TERM (TODAY THROUGH MONDAY)...
A WEAK SHEAR AXIS IS DRAPED ALONG AND NW OF I-35 EARLY THIS
MORNING. LIGHT CONVECTION IS DEVELOPING ALONG THIS AXIS AND IS
DEPICTED FAIRLY WELL BY THE RECENT RUC RUNS. THE SHEAR AXIS IS
EXPECTED BY MODEL CONSENSUS TO SHIFT EAST AND POSSIBLY PUSH THE
HIGHER RAIN CHANCES AND PWAT VALUES INTO EASTERN COUNTIES LATE
TODAY WHILE MID LEVEL STABILITY BUILDS INTO WESTERN AND CENTRAL
COUNTIES. THE INCREASING STABILITY IS SUGGESTED TO BE OVER A
SHORT PERIOD... LASTING THROUGH LATE MONDAY. WITH REDUCED CLOUD
COVER EXPECTED THE MILD AFTERNOON TEMPERATURES OF TODAY SHOULD
REBOUND 2-4 DEGREES WARMER FOR MONDAY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
A SMALL DISTURBANCE IS EXPECTED TO TRIGGER CONVECTION OVER THE
SOUTHERN PLAINS LATE MONDAY AND POSSIBLY SEND A WEAKENING COMPLEX
OF STORMS INTO THE AREA MONDAY NIGHT INTO TUESDAY. WITH NORTHERLY
MID-LEVEL FLOW DEVELOPING DURING THIS PERIOD...SOME MODELS...
ESPECIALLY THE CANADIAN...DEVELOP A LOW PRESSURE CENTER OVER
CENTRAL TX AND AMPLIFY RAIN CHANCES INTO A POSSIBLE FLOOD PATTERN.
A MORE CONSERVATIVE BLEND OF THE DRIER GFS AND WETTER ECMWF IS
PREFERRED FOR FORECAST CONSISTENCY...BUT WILL NOTE THAT THE
BROADER WEAKNESS OVER TX IS TYPICAL FOR JUNE HEAVY RAIN EVENTS.
BASED ON MODEL CONSENSUS AN ENHANCEMENT OF DIURNAL THUNDERSTORM
ACTIVITY IS PROBABLE FOR AREAS ALONG AND EAST OF I-35 WEDNESDAY
THROUGH SATURDAY...AS EVEN THE DRIER GFS KEEPS A WEAK MID LEVEL
SHEAR AXIS OVER CENTRAL TX THROUGH AS LATE AS THURSDAY.
THE CONSENSUS OF WETTER AND DRIER MODEL SOLUTIONS IN THE EXTENDED
FORECAST CONTINUES TO KEEP TEMPERATURES RELATIVELY MILD.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 90 74 92 74 90 / 30 10 10 20 20
AUSTIN BERGSTROM INTL AIRPORT 90 73 93 73 90 / 30 10 10 20 20
NEW BRAUNFELS MUNI AIRPORT 91 74 93 73 90 / 20 10 10 10 20
BURNET MUNI AIRPORT 87 72 91 72 88 / 20 - 20 20 20
DEL RIO INTL AIRPORT 91 74 96 75 94 / 10 - 10 10 10
GEORGETOWN MUNI AIRPORT 89 73 92 73 90 / 20 10 20 20 20
HONDO MUNI AIRPORT 92 73 93 73 93 / 20 10 10 10 20
SAN MARCOS MUNI AIRPORT 90 74 92 73 90 / 20 10 10 20 20
LA GRANGE - FAYETTE REGIONAL 91 76 93 75 90 / 30 10 20 20 30
SAN ANTONIO INTL AIRPORT 90 76 93 75 90 / 20 10 10 10 20
STINSON MUNI AIRPORT 92 75 94 75 92 / 20 10 10 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...99
SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1028 AM EDT SUN JUN 22 2014
.SYNOPSIS...
WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND
TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A
DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD
FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE
WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1028 AM EDT SUNDAY...
FORECAST AREA REMAINS BETWEEN UPPER LOW OVER THE NORTHEAST UNITED
STATES AND UPPER RIDGE OVER THE SOUTHERN PLAINS TODAY AND TONIGHT.
NO DISTINCT SHORT WAVES COMING THROUGH THE UPPER FLOW BUT 500 MB
TEMPERATURES DO DROP A FEW DEGREES BY THIS AFTERNOON.
ENOUGH HIGH SURFACE HIGH PRESSURE WAS BUILD IN EAST OF THE BLUE
RIDGE THAT WINDS HAVE COME AROUND TO THE NORTHEAST. LOW CLOUDS HAVE
DEVELOPED IN THE WEDGE AND SPREAD WEST TOWARD THE BLUE RIDGE. OVER
THE MOUNTAINS THE WIND WAS LIGHT FROM THE WEST. THIS WILL CREATE
DIFFERENTIAL HEATING DURING THE DAY AND SOME LOW LEVEL CONVERGENCE.
THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE ALONG THE
CONVERGENCE ZONE ON THE WEST SIDE OF THE LOW CLOUDS WHERE
INSTABILITY WILL BE BETTER.
BUFKIT SHOWED THE THICKNESS OF THE STRATUS WILL ONLY BE A FEW
HUNDRED FEET AND THE SUMMER SUN WILL GRADUALLY ERODE THE LAYER. AS
THE CLOUDS ERODE AND RETREAT BACK THE EAST THE CHANCE OF SHOWERS AND
THUNDERSTORMS WILL ALSO SHIFT EAST. HRRR AND OTHER SHORT TERM
GUIDANCE SHOWED STORMS DEVELOPING NORTH OF THE FORECAST AREA THEN
MOVING SOUTH AND EXTENDING FROM BATH COUNTY TO SURRY COUNTY BY LATE
AFTERNOON.
CLOUDS WILL ALSO CREATE A LARGER SPREAD IN MAXIMUM TEMPERATURES FOR
TODAY. THE SOONER THE CLOUDS MIX OUT THE WARMER IT WILL BE IN THE
EAST. LOW LEVEL MOISTURE FORECASTS SUGGEST CLOUDS WILL FILL BACK IN
EAST OF THE BLUE RIDGE OVERNIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
AS OF 300 AM EDT SUNDAY...
WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS
FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF
APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO
SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM
OFF THE SOUTHEAST COAST.
SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE
OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST
EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY...
WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS
CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF
THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS
TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID
ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF
SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT.
DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS
OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL
BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE...
ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA
WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO
THE DEPARTING SURFACE RIDGE.
WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM
PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT
SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND
THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER
CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K
FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN
LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO
SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY
SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED
TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME.
ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING
AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT
INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER
AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED.
THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL
UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO
RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE
PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE
TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST.
MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND
GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S
CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS
GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY
LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW
BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 140 PM EDT SATURDAY...
I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL
BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK
NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN.
OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY
AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE
WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF
THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING
ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES.
NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS
STAY WELL NORTH OF THE MID ATLANTIC.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
AS OF 745 AM EDT SUNDAY...
LOW PRESSURE WAS OVER SOUTHEAST NORTH CAROLINA WITH A FRONT
TRAILING BACK INTO THE TENNESSEE VALLEY. ENOUGH HIGH PRESSURE WAS
BUILDING INTO THE REGION NORTH OF THIS SYSTEM.
FIRST VISIBLE SATELLITE PICTURES OF THE DAY SHOWERS A LAYER OF
MVFR STRATUS JUST EAST OF KROA...WITH SEVERAL BREAKS IN THE CLOUD
DECK.THIS CLOUD LAYER WAS SHALLOW AND CLOUDS WILL ERODE IN THE
MORNING WITH HEATING. MODERATE CONFIDENCE THAT A MAJORITY OF THE
LOW CLOUDS WILL BE GONE BY 14Z/10AM.
ALONG THE EDGE OF THIS RELATIVELY MORE STABLE AIR...EXPECT THE DEVELOPMENT
OF SHOWERS AND THUNDERSTORMS BY AFTERNOON. MOST LIKELY LOCATION
FOR STORM IS ALONG A CORRIDOR FROM KHSP TO KMWK...SO HAVE ADDED
THUNDER IN THE VCNTY TO THE KBCB/KROA AND KLYH TAFS AFTER
21Z/5PM. MUCH OF THE PRECIPITATION WILL DIMINISH WITH THE LOSS OF
HEATING THIS EVENING.
CEILINGS MAY LOWER AGAIN OVERNIGHT...ESPECIALLY EAST OF THE BLUE
RIDGE. MODELS HAVE MVFR CLOUDS MOVING BACK IN...MAINLY AFTER
08Z/4AM.
EXTENDED AVIATION DISCUSSION...
DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF
AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF
ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET
CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS
OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING
PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE
FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING
FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS
OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE
NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE
PREVIOUS AFTERNOON.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/RCS
SHORT TERM...WERT
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
747 AM EDT SUN JUN 22 2014
.SYNOPSIS...
WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND
TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A
DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD
FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE
WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 345 AM EDT SUNDAY...
FORECAST AREA REMAINS BETWEEN UPPER LOW OVER THE NORTHEAST UNITED
STATES AND UPPER RIDGE OVER THE SOUTHERN PLAINS TODAY AND TONIGHT.
NO DISTINCT SHORT WAVES COMING THROUGH THE UPPER FLOW BUT 500 MB
TEMPERATURES DO DROP A FEW DEGREES BY THIS AFTERNOON.
ENOUGH HIGH SURFACE HIGH PRESSURE WAS BUILD IN EAST OF THE BLUE
RIDGE THAT WINDS HAVE COME AROUND TO THE NORTHEAST. LOW CLOUDS HAVE
DEVELOPED IN THE WEDGE AND SPREAD WEST TOWARD THE BLUE RIDGE. OVER
THE MOUNTAINS THE WIND WAS LIGHT FROM THE WEST. THIS WILL CREATE
DIFFERENTIAL HEATING DURING THE DAY AND SOME LOW LEVEL CONVERGENCE.
THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE ALONG THE
CONVERGENCE ZONE ON THE WEST SIDE OF THE LOW CLOUDS WHERE
INSTABILITY WILL BE BETTER.
BUFKIT SHOWED THE THICKNESS OF THE STRATUS WILL ONLY BE A FEW
HUNDRED FEET AND THE SUMMER SUN WILL GRADUALLY ERODE THE LAYER. AS
THE CLOUDS ERODE AND RETREAT BACK THE EAST THE CHANCE OF SHOWERS AND
THUNDERSTORMS WILL ALSO SHIFT EAST. HRRR AND OTHER SHORT TERM
GUIDANCE SHOWED STORMS DEVELOPING NORTH OF THE FORECAST AREA THEN
MOVING SOUTH AND EXTENDING FROM BATH COUNTY TO SURRY COUNTY BY LATE
AFTERNOON.
CLOUDS WILL ALSO CREATE A LARGER SPREAD IN MAXIMUM TEMPERATURES FOR
TODAY. THE SOONER THE CLOUDS MIX OUT THE WARMER IT WILL BE IN THE
EAST. LOW LEVEL MOISTURE FORECASTS SUGGEST CLOUDS WILL FILL BACK IN
EAST OF THE BLUE RIDGE OVERNIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
AS OF 300 AM EDT SUNDAY...
WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS
FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF
APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO
SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM
OFF THE SOUTHEAST COAST.
SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE
OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST
EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY...
WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS
CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF
THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS
TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID
ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF
SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT.
DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS
OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL
BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE...
ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA
WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO
THE DEPARTING SURFACE RIDGE.
WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM
PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT
SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND
THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER
CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K
FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN
LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO
SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY
SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED
TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME.
ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING
AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT
INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER
AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED.
THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL
UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO
RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE
PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE
TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST.
MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND
GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S
CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS
GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY
LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW
BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 140 PM EDT SATURDAY...
I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL
BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK
NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN.
OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY
AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE
WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF
THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING
ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES.
NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS
STAY WELL NORTH OF THE MID ATLANTIC.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 745 AM EDT SUNDAY...
LOW PRESSURE WAS OVER SOUTHEAST NORTH CAROLINA WITH A FRONT
TRAILING BACK INTO THE TENNESSEE VALLEY. ENOUGH HIGH PRESSURE WAS
BUILDING INTO THE REGION NORTH OF THIS SYSTEM.
FIRST VISIBLE SATELLITE PICTURES OF THE DAY SHOWERS A LAYER OF
MVFR STRATUS JUST EAST OF KROA...WITH SEVERAL BREAKS IN THE CLOUD
DECK.THIS CLOUD LAYER WAS SHALLOW AND CLOUDS WILL ERODE IN THE
MORNING WITH HEATING. MODERATE CONFIDENCE THAT A MAJORITY OF THE
LOW CLOUDS WILL BE GONE BY 14Z/10AM.
ALONG THE EDGE OF THIS RELATIVELY MORE STABLE AIR...EXPECT THE DEVELOPMENT
OF SHOWERS AND THUNDERSTORMS BY AFTERNOON. MOST LIKELY LOCATION
FOR STORM IS ALONG A CORRIDOR FROM KHSP TO KMWK...SO HAVE ADDED
THUNDER IN THE VCNTY TO THE KBCB/KROA AND KLYH TAFS AFTER
21Z/5PM. MUCH OF THE PRECIPITATION WILL DIMINISH WITH THE LOSS OF
HEATING THIS EVENING.
CEILINGS MAY LOWER AGAIN OVERNIGHT...ESPECIALLY EAST OF THE BLUE
RIDGE. MODELS HAVE MVFR CLOUDS MOVING BACK IN...MAINLY AFTER
08Z/4AM.
EXTENDED AVIATION DISCUSSION...
DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF
AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF
ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET
CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS
OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING
PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE
FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING
FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS
OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE
NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE
PREVIOUS AFTERNOON.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...WERT
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1254 PM CDT SUN JUN 22 2014
.DISCUSSION...
1126 AM CDT
MAIN UPDATES THIS MORNING WERE TO ADD SLIGHT CHANCE FOR THUNDER
ACROSS THE WESTERN CWA LATE THIS AFTERNOON AND EARLY EVENING.
STRATUS AND FOG CONTINUE TO LIFT/DISSIPATE LATE THIS MORNING WITH
SKIES BECOMING MORE PARTLY CLOUDY TO AT TIMES PARTLY
SUNNY. TEMPERATURES ARE STEADILY REBOUNDING AND WILL RISE INTO THE
MID 80S THIS AFTERNOON FOR MOST AREAS...WHILE DEWPOINTS REMAIN IN
THE 60S AND STILL PROVIDING FOR SOME MUGGY CONDITIONS. NOT OVERLY
CONCERNED AT THIS TIME...BUT AM DEFINITELY WATCHING COMPLEX OF
THUNDERSTORMS MOVING EAST ACROSS EAST CENTRAL IOWA. MOST GUIDANCE
THIS MORNING HAS THIS COMPLEX REACHING THE FAR WESTERN CWA BY
EARLY EVENING...BUT RAPIDLY WEAKENING AT THAT TIME. THIS SCENARIO
DOES SEEM POSSIBLE AS INSTABILITY IN PLACE WOULD BE LOWERING. IF
THIS COMPLEX OF STORMS WERE TO TAKE ON A MORE STEADY PACE
EASTWARD TODAY...THEY COULD BE NEAR THE FAR WESTERN CWA BY LATE
THIS AFTERNOON. THIS WOULD BE CONCERNING AS HIGH DEWPOINT AIR
POOLING ALONG A LINGERING BOUNDARY/TROUGH AXIS AS WELL AS STEEP
LOW LEVEL LAPSE RATES FORECAST TO BE IN PLACE COULD AID IN
ISOLATED STRONG THUNDERSTORM DEVELOPMENT IN THE WESTERN
CWA...PRIMARILY ALONG AND WEST OF INTERSTATE 39. THE UNCERTAINTIES
IN PLACE HAVE PRECLUDED ANY HIGHER WORDING FOR THUNDERSTORM
POTENTIAL IN THE HWO AS WELL AS HIGHER POPS OUT WEST BEYOND THE
ADDED SLIGHT CHANCE. WILL CLOSELY MONITOR THIS POTENTIAL AND MAKE
NECESSARY UPDATES OVER THE NEXT COUPLE OF HOURS AS NEED BE.
RODRIGUEZ
//PREV DISCUSSION...
348 AM CDT
A RATHER CHALLENGING FORECAST TONIGHT WITH RESPECT TO SENSIBLE
WEATHER DETAILS...ESPECIALLY WITH RESPECT TO PCPN CHANCES OVER THE
NEXT SEVERAL DAYS.
THE ENVIRONMENT REMAINS VERY MOIST...WITH PWATS OF 1.5 TO ALMOST 2.0
INCHES ACROSS THE MIDWEST...UPPER MIDWEST AND GREAT LAKES REGION...
WHILE A VERY WEAK GRADIENT SFC PATTERN COVERS THE REGION. IN THE
ABSENCE OF ANY SIGNIFICANT SFC FORCING...ANY CONVECTIVE ACTIVITY
OVER THE NEXT SEVERAL DAYS WILL LARGELY RELY ON UPPER LEVEL FORCING
AS THE SURFACE REFLECTION OF UPPER LEVELS FEATURES WILL BE RATHER
WEAK.
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...THE MAIN
ISSUE WILL BE FOG AND STRATUS DEVELOPMENT IN THE WAKE OF ANOTHER
ROUND OF THUNDERSTORMS AND HEAVY RAIN THAT SWEPT THROUGH THE REGION
SATURDAY AFTERNOON AND EVENING. LATEST SATELLITE FOG IMAGERY HAD
INDICATED AN AREA OF LOW STRATUS AND FOG SPREADING OFF THE LAKE INTO
NERN IL. WITH CI OBSCURING ANY LOW FEATURES IN THE SATELLITE
IMAGERY...HAVE FOLLOWED SFC OB TRENDS...WHICH GENERALLY INDICATE LOW
STRATUS OVER MUCH OF THE CWA NORTH OF THE I-80 CORRIDOR. HAVE HELD
OFF ON ISSUING A DENSE FOG ADVISORY FOR NOW SINCE THE DENSE FOG
APPEARS TO BE RATHER SPOTTY. WITH MORE HIGH CLOUD OVERSPREADING THE
REGION...THE CHANCES FOR WIDESPREAD AREAS OF FOG WITH VIS AT OR LESS
THAN 1/4SM SEEMS LIMITED. FOR THE REMAINDER OF SUNDAY...HAVE BACKED
OFF ON POPS OVER ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SOUTH
AS THE AREA RECOVERS FROM EARLIER CONVECTION. A VERY WEAK AND
DIFFUSE QUASI-STATIONARY FRONT REMAINS DRAPED ACROSS NRN/CNTRL IL
INTO THE OHIO VALLEY AND LINGERING OUTFLOW BOUNDARIES COULD IGNITE
SOME TSRA/SHRA TODAY...AND SHOULD BE LIMITED TO THE FAR SOUTHERN
PORTIONS OF THE CWA WHICH WILL NOT SEE THE STRATUS AND FOG. ANOTHER
CONCERN FOR THIS AFTERNOON WILL BE ANOTHER LAKE BREEZE MOVING
INLAND. WITH A VERY WEAK GRADIENT IN PLACE...LAKE BREEZE
DEVELOPMENT IS LIKELY...ESPECIALLY IF NERON IL CAN BURN OFF THE
STRATUS AND FOR EARLY ENOUGH TO SET UP ADEQUATE DIFFERENTIAL HEATING
BETWEEN THE COLD LAKE AND WARMER LAND. IF THIS DOES
OCCUR...ADDITION FOG TRAPPED UNDER A MARINE LAYER INVERSION WOULD
LIKELY PUSH INLAND BEHIND THE BOUNDARY. SO..WHILE IT WOULD BE
CLIMATOLOGICALLY UNUSUAL TO THINK ABOUT INTRODUCING FOG AND/OR
STRATUS INTO THE FORECAST FOR THE AFTERNOON HOURS...THE UNUSUALLY
COLD LAKE WATERS MAKE THIS A DISTINCT POSSIBILITY. ANTICIPATE THAT
THE REST OF SUNDAY AND SUNDAY EVENING SHOULD BE DRY...WITH THE NEXT
SIGNIFICANT CHANCE FOR PCPN NOT COMING UNTIL LATE SUNDAY NIGHT.
WITH AN UPPER LOW REMAINING NEARLY STATIONARY OVER LAKE WINNIPEG AND
BROAD HIGH PRESSURE ACROSS THE SRN CONUS AND THE GLFMEX...WEAK ZONAL
FLOW CONTINUES ALOFT...WITH A SERIES OF WEAK SHORTWAVES RIPPLING
THROUGH THE NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. AS IS
TYPICAL FOR ZONAL FLOW...TIMING INDIVIDUAL SHORTWAVES IS VERY
DIFFICULT...BUT THE GLOBAL MODELS HAVE BEEN RELATIVELY CONSISTENT ON
TRACKING A MODERATE SHORTWAVE ACROSS THE NORTHERN PLAINS TO THE
UPPER MISSISSIPPI VALLEY BY THIS EVENING. THIS FEATURE SHOULD THEN
CROSS THE REGION LATE SUNDAY NIGHT AND MONDAY MORNING...BRINGING THE
NEXT SIGNIFICANT CHANCE FOR SHOWERS AND THUNDERSTORMS. THIS FEATURE
IS RESPONSIBLE FOR THE ONGOING CONVECTION OVER THE CENTRAL PLAINS
AND IS WELL INITIALIZED IN THE GLOBAL MODELS...SO IN DEFERENCE TO
GOOD INITIALIZATION AND THE RELATIVELY DECENT MODEL CONTINUITY...HAVE
GONE WITH CATEGORICAL POPS AS THE SYSTEM CROSSES THE REGION.
ENVIRONMENTAL CONDITIONS WILL BE FAVORABLE FOR LOCALLY HEAVY
RAINFALL...WITH PWATS AROUND 1.75 INCHES AND WEAK STEERING FLOW AS
THE SYSTEM CROSSES THE REGION. AS THERE HAS BEEN A CONSIDERABLE
AMOUNT OF RAIN OVER THE REGION IN RECENT DAYS...THE GROUND IS
LARGELY SATURATED AND AREA RIVERS HAVE LESS CAPACITY FROM THE
RESULTANT RUNOFF...SO THE POTENTIAL FOR FLOODING WILL NEED TO BE
CONSIDERED. THERE IS A SMALL SEVERE THREAT WITH THESE THUNDERSTORMS
AS THE ENVIRONMENT WILL BE MOIST AND UNSTABLE...AWAY FROM THE
STABILIZATION OF THE LAKE BREEZE/MARINE LAYER MOVING INLAND.
THE MAIN SHORTWAVE AND THE ASSOCIATED WEAK SFC FRONT IS EXPECTED TO
PUSH THROUGH THE REGION BY TUESDAY. FROM TUESDAY THROUGH THE
REMAINDER OF THE FORECAST PERIOD...FORECAST CONFIDENCE DECREASES
RAPIDLY. THE UPPER LOW OVER CANADA IS EXPECTED TO SHOW LITTLE
PROGRESSION WITH A SERIES OF WEAK SHORTWAVES RIPPLING THROUGH THE
ZONAL FLOW ALOFT OVER THE REGION. WHILE THE MODELS GENERALLY AGREE
THAT THERE WILL BE LITTLE CHANGE TO THE LOW AMPLITUDE PATTERN
ALOFT...TIMING ANY OF THE SHORTWAVES RIPPLING THROUGH THE FLOW WILL
BE DIFFICULT. SO...WHILE THE FORECAST FROM TUESDAY EVENING THROUGH
THE END OF THE FORECAST PERIOD...SATURDAY...MAY SOUND LIKE A BROKEN
RECORD (AT LEAST TO THOSE OF US OLD ENOUGH TO REMEMBER RECORDS AND
WHAT THEY SOUND LIKE WHEN BROKEN)...THERE WILL BE LITTLE CHANGE TO
THE IN SITU CONDITIONS WITH DEEP LAYER MOISTURE IN PLACE...ANY MID
LEVEL FORCING FROM PASSING SHORTWAVES WILL BE ADEQUATE TO GENERATE
SHOWERS AND THUNDERSTORMS. SO...WILL CARRY SLIGHT CHANCE TO CHANCE
POPS THROUGH MUCH OF THE REMAINDER OF THE FORECAST PERIOD.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* INCREASING CHANCE OF SHRA/TSRA TONIGHT AND TOMORROW.
* EAST TO NORTHEAST WIND NEAR THRESHOLD OF STAYING ON WEST FLOW
FOR ORD.
LENNING
//DISCUSSION...UPDATED 18Z...
THE CLUSTER OF SHOWERS AND THUNDERSTORMS MOVING ACROSS IOWA TODAY
HAS NOT BEEN WELL HANDLED BY ALL MODELS...SO IT IS HARD TO PIN
DOWN THE EXPECTED EVOLUTION INTO THIS EVENING AND OVERNIGHT. GIVEN
THE DEGREE OF INSTABILITY...IT IS QUITE POSSIBLE THESE WILL HANG
TOGETHER INTO THE WESTERN PORTION OF THE FCST AREA AND REACH RFD
BY LATE AFTERNOON TO EARLY EVENING. LOSS OF DIURNAL HEATING LATER
THIS EVENING MAY DAMPEN CONVECTION SOMEWHAT AFTER SUNDOWN AS THEY
WORK INTO THE CHICAGO METRO AREA. EVEN SO...HAVE MOVED UP START
TIME OF VCSH AT ORD/MDW TERMINALS.
GIVEN THE DEEP AND MOIST BUT RELATIVELY WARM VERTICAL TEMPERATURE
AND MOISTURE PROFILE...NOT CERTAIN HOW MUCH THUNDER THE AREA WILL
SEE AHEAD OF A FRONTAL PASSAGE TOWARD MIDDAY TOMORROW...BUT
INCLUDED A WINDOW OF VCTS CORRESPONDING TO APPROXIMATE TIME OF
FROPA.
AS FOR WINDS...EXPECT GRADUAL VEERING THROUGH THE PERIOD...WITH A
TURN TOWARD WESTERLY AFTER FROPA TOMORROW. LIGHT SPEEDS FOR MOST
OF THE AFTERNOON MAY ALLOW CONTINUED WEST FLOW CONFIGURATION AT
ORD...BUT SPEEDS ARE EXPECTED TO INCREASE A COUPLE OF KTS AS THE
AFTERNOON PROGRESSES.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN SHRA TIMING TONIGHT AND TOMORROW.
* MEDIUM TO HIGH CONFIDENCE IN WINDS.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...TSRA LIKELY.
TUESDAY...CHANCE OF SHRA.
WEDNESDAY...SLIGHT CHANCE OF SHRA.
THURSDAY-SATURDAY...CHANCE OF SHRA AND SLIGHT CHANCE OF TSRA.
MTF
&&
.MARINE...
205 AM CDT
A LIGHT PRESSURE GRADIENT WILL BE SEEN OVER LAKE MICHIGAN TODAY DUE
TO EXPANSIVE HIGH PRESSURE CENTERED OVER THE EASTERN LAKES INTO NEW
ENGLAND. THIS REGIME OFFERS ONSHORE FLOW INTO ILLINOIS AND INDIANA
THAT SHOULD INCREASE TO AROUND 10 TO 15 KT DURING MIDDAY BEFORE
DIMINISHING BY SUNDOWN. THIS SETUP WILL ALSO ALLOW DENSE FOG TO
CONTINUE ACROSS MUCH OF THE LAKE AS THERE WILL BE LITTLE TURNOVER
OF THE MOIST AIRMASS OVER THE COOL WATERS. LOW PRESSURE WILL
APPROACH THE LAKE ON MONDAY AND EVENTUALLY MOVE OVER THE NORTHERN
PART OF IT MONDAY NIGHT. SOUTHERLY FLOW IS EXPECTED IN ADVANCE OF
THIS AND COULD PUSH THE FOG FURTHER NORTH ON MONDAY. IN
ADDITION...THUNDERSTORM CHANCES WILL INCREASE AND COULD DISRUPT
SOME OF THE FOG AS WELL. SO HAVE NOT EXTENDED THE DENSE FOG
ADVISORY ANY FURTHER THAN MONDAY MORNING AT THIS TIME...ALTHOUGH
FOR NORTHERN AND CENTRAL PORTIONS OF THE LAKE IT MAY NEED TO BE.
THE SYSTEM COLD FRONT WILL LIKELY PASS VERY EARLY TUESDAY MORNING
AND TURN WINDS WESTERLY. A SECOND COLD FRONT...MORE OF A BACKDOOR
ONE...IS ANTICIPATED TO PROGRESS SOUTHWARD TUESDAY NIGHT AND LEAD
TO NORTHERLY WINDS.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-
LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-
LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 10 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1224 PM CDT Sun Jun 22 2014
.DISCUSSION...
ISSUED 1005 AM CDT Sun Jun 22 2014
Convection developed just southwest of our CWA earlier this
morning, along the remnants of the outflow boundary from
yesterday`s storms. Latest surface map shows this boundary arcing
northwest along the Mississippi River then into central Iowa,
where a line of strong storms was moving through that area. Have
been seeing some increase in showers recently along this boundary
in the northeast corner of Missouri, and this should increase over
the next few hours. Latest RAP and HRRR guidance showing the
western CWA still with the best chances for showers/storms today,
with some more isolated activity across the east.
Have updated the zones/grids to reflect the storms mainly being
during the afternoon, as well as some adjustments to the sky
cover. Temperatures are largely in good shape and only required
some minor adjustments over the next few hours.
Geelhart
&&
.AVIATION...
ISSUED 1222 PM CDT Sun Jun 22 2014
Scattered convection has developed over western Illinois and is
slowly moving east. AWIPS timing tools would place it in the
KPIA/KSPI area in the 20-21Z time frame, but some uncertainty in
the eastward progression, so will limit afternoon VCTS mention to
these two sites at the moment, and bring them into KBMI/KDEC
toward 00Z. A larger area of showers and scattered storms is
expected to move through after 06Z. Then after a short break
beginning near sunrise, additional convective development is
anticipated toward the end of the forecast period, as a cold front
moves in from the northwest.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun Jun 22 2014
Though an area of showers and thunderstorms moved across much of
ILX yesterday evening, the air mass overall remains very much the
same. Hot and humid conditions persist. A weak frontal boundary
has meandered just north of the area and the next couple of
impulses are just to the west, lining up for arrival later today.
In between waves, much of this morning may be dry in most
locations. Not taking out the possibility for some very isolated
showers...but chances will increase this afternoon/later this
evening with the approach of the next wave. Surface low associated
with the next wave is weak and as a result, models are not doing
well with its evolution in the weak pattern as a whole. Models
continue to over produce the coverage of the convection, then
suffer the feedback issues. Chance/slight chance dominates, with
some minor adjustments for drier pds. Temps above normal and heat
indices in the 90s to wrap up the weekend until the next cool
front moves through Mon/Mon afternoon.
SHORT TERM...Today and tonight...
Hot. Humid. Heat indices into the mid 90s and chances of precip
increasing into the afternoon/evening hours. Waves to the west
showing varied paths and models connecting the dots on the qpf
leave a lot to be desired. Waves passing north and south remain a
possibility, but diurnal impacts and enhancement is just too
strong a possibility with leftover outflows in the region to NOT
have pops around this evening. Very similar tune to the trend from
the past few days. Coverage sporadic, plenty of ingredients to
work with, just non consistent triggers.
LONG TERM...Monday through Friday...
Upper trof/wave pushing through the region on Monday into Tuesday
bringing signif chance, increasing from Sun night into Monday
night. Models speeding up with initial arrival of boundary on
Monday, and slowing its departure...as this run has been a little
more diffuse with the pops and may see this trending with a +/- 12
hrs on either side. Not an absolute at this point, but
Monday/Monday night having the best chances at significant precip
through the fcst. A slightly cooler Tuesday through the end
of the week. Still warm, but potentially less humidity as winds
become more westerly on Tuesday, picking up a northerly component
by Wednesday. Forecast trending drier from late Tuesday through
Wednesday. Another wave Thursday brings back some pops ahead of
the next big storm system developing over the SW for late next
weekend.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1109 AM CDT SUN JUN 22 2014
.DISCUSSION...
348 AM CDT
A RATHER CHALLENGING FORECAST TONIGHT WITH RESPECT TO SENSIBLE
WEATHER DETAILS...ESPECIALLY WITH RESPECT TO PCPN CHANCES OVER THE
NEXT SEVERAL DAYS.
THE ENVIRONMENT REMAINS VERY MOIST...WITH PWATS OF 1.5 TO ALMOST 2.0
INCHES ACROSS THE MIDWEST...UPPER MIDWEST AND GREAT LAKES REGION...
WHILE A VERY WEAK GRADIENT SFC PATTERN COVERS THE REGION. IN THE
ABSENCE OF ANY SIGNIFICANT SFC FORCING...ANY CONVECTIVE ACTIVITY
OVER THE NEXT SEVERAL DAYS WILL LARGELY RELY ON UPPER LEVEL FORCING
AS THE SURFACE REFLECTION OF UPPER LEVELS FEATURES WILL BE RATHER
WEAK.
FOR THE REMAINDER OF THE NIGHT AND INTO SUNDAY MORNING...THE MAIN
ISSUE WILL BE FOG AND STRATUS DEVELOPMENT IN THE WAKE OF ANOTHER
ROUND OF THUNDERSTORMS AND HEAVY RAIN THAT SWEPT THROUGH THE REGION
SATURDAY AFTERNOON AND EVENING. LATEST SATELLITE FOG IMAGERY HAD
INDICATED AN AREA OF LOW STRATUS AND FOG SPREADING OFF THE LAKE INTO
NERN IL. WITH CI OBSCURING ANY LOW FEATURES IN THE SATELLITE
IMAGERY...HAVE FOLLOWED SFC OB TRENDS...WHICH GENERALLY INDICATE LOW
STRATUS OVER MUCH OF THE CWA NORTH OF THE I-80 CORRIDOR. HAVE HELD
OFF ON ISSUING A DENSE FOG ADVISORY FOR NOW SINCE THE DENSE FOG
APPEARS TO BE RATHER SPOTTY. WITH MORE HIGH CLOUD OVERSPREADING THE
REGION...THE CHANCES FOR WIDESPREAD AREAS OF FOG WITH VIS AT OR LESS
THAN 1/4SM SEEMS LIMITED. FOR THE REMAINDER OF SUNDAY...HAVE BACKED
OFF ON POPS OVER ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SOUTH
AS THE AREA RECOVERS FROM EARLIER CONVECTION. A VERY WEAK AND
DIFFUSE QUASI-STATIONARY FRONT REMAINS DRAPED ACROSS NRN/CNTRL IL
INTO THE OHIO VALLEY AND LINGERING OUTFLOW BOUNDARIES COULD IGNITE
SOME TSRA/SHRA TODAY...AND SHOULD BE LIMITED TO THE FAR SOUTHERN
PORTIONS OF THE CWA WHICH WILL NOT SEE THE STRATUS AND FOG. ANOTHER
CONCERN FOR THIS AFTERNOON WILL BE ANOTHER LAKE BREEZE MOVING
INLAND. WITH A VERY WEAK GRADIENT IN PLACE...LAKE BREEZE
DEVELOPMENT IS LIKELY...ESPECIALLY IF NERON IL CAN BURN OFF THE
STRATUS AND FOR EARLY ENOUGH TO SET UP ADEQUATE DIFFERENTIAL HEATING
BETWEEN THE COLD LAKE AND WARMER LAND. IF THIS DOES
OCCUR...ADDITION FOG TRAPPED UNDER A MARINE LAYER INVERSION WOULD
LIKELY PUSH INLAND BEHIND THE BOUNDARY. SO..WHILE IT WOULD BE
CLIMATOLOGICALLY UNUSUAL TO THINK ABOUT INTRODUCING FOG AND/OR
STRATUS INTO THE FORECAST FOR THE AFTERNOON HOURS...THE UNUSUALLY
COLD LAKE WATERS MAKE THIS A DISTINCT POSSIBILITY. ANTICIPATE THAT
THE REST OF SUNDAY AND SUNDAY EVENING SHOULD BE DRY...WITH THE NEXT
SIGNIFICANT CHANCE FOR PCPN NOT COMING UNTIL LATE SUNDAY NIGHT.
WITH AN UPPER LOW REMAINING NEARLY STATIONARY OVER LAKE WINNIPEG AND
BROAD HIGH PRESSURE ACROSS THE SRN CONUS AND THE GLFMEX...WEAK ZONAL
FLOW CONTINUES ALOFT...WITH A SERIES OF WEAK SHORTWAVES RIPPLING
THROUGH THE NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. AS IS
TYPICAL FOR ZONAL FLOW...TIMING INDIVIDUAL SHORTWAVES IS VERY
DIFFICULT...BUT THE GLOBAL MODELS HAVE BEEN RELATIVELY CONSISTENT ON
TRACKING A MODERATE SHORTWAVE ACROSS THE NORTHERN PLAINS TO THE
UPPER MISSISSIPPI VALLEY BY THIS EVENING. THIS FEATURE SHOULD THEN
CROSS THE REGION LATE SUNDAY NIGHT AND MONDAY MORNING...BRINGING THE
NEXT SIGNIFICANT CHANCE FOR SHOWERS AND THUNDERSTORMS. THIS FEATURE
IS RESPONSIBLE FOR THE ONGOING CONVECTION OVER THE CENTRAL PLAINS
AND IS WELL INITIALIZED IN THE GLOBAL MODELS...SO IN DEFERENCE TO
GOOD INITIALIZATION AND THE RELATIVELY DECENT MODEL CONTINUITY...HAVE
GONE WITH CATEGORICAL POPS AS THE SYSTEM CROSSES THE REGION.
ENVIRONMENTAL CONDITIONS WILL BE FAVORABLE FOR LOCALLY HEAVY
RAINFALL...WITH PWATS AROUND 1.75 INCHES AND WEAK STEERING FLOW AS
THE SYSTEM CROSSES THE REGION. AS THERE HAS BEEN A CONSIDERABLE
AMOUNT OF RAIN OVER THE REGION IN RECENT DAYS...THE GROUND IS
LARGELY SATURATED AND AREA RIVERS HAVE LESS CAPACITY FROM THE
RESULTANT RUNOFF...SO THE POTENTIAL FOR FLOODING WILL NEED TO BE
CONSIDERED. THERE IS A SMALL SEVERE THREAT WITH THESE THUNDERSTORMS
AS THE ENVIRONMENT WILL BE MOIST AND UNSTABLE...AWAY FROM THE
STABILIZATION OF THE LAKE BREEZE/MARINE LAYER MOVING INLAND.
THE MAIN SHORTWAVE AND THE ASSOCIATED WEAK SFC FRONT IS EXPECTED TO
PUSH THROUGH THE REGION BY TUESDAY. FROM TUESDAY THROUGH THE
REMAINDER OF THE FORECAST PERIOD...FORECAST CONFIDENCE DECREASES
RAPIDLY. THE UPPER LOW OVER CANADA IS EXPECTED TO SHOW LITTLE
PROGRESSION WITH A SERIES OF WEAK SHORTWAVES RIPPLING THROUGH THE
ZONAL FLOW ALOFT OVER THE REGION. WHILE THE MODELS GENERALLY AGREE
THAT THERE WILL BE LITTLE CHANGE TO THE LOW AMPLITUDE PATTERN
ALOFT...TIMING ANY OF THE SHORTWAVES RIPPLING THROUGH THE FLOW WILL
BE DIFFICULT. SO...WHILE THE FORECAST FROM TUESDAY EVENING THROUGH
THE END OF THE FORECAST PERIOD...SATURDAY...MAY SOUND LIKE A BROKEN
RECORD (AT LEAST TO THOSE OF US OLD ENOUGH TO REMEMBER RECORDS AND
WHAT THEY SOUND LIKE WHEN BROKEN)...THERE WILL BE LITTLE CHANGE TO
THE IN SITU CONDITIONS WITH DEEP LAYER MOISTURE IN PLACE...ANY MID
LEVEL FORCING FROM PASSING SHORTWAVES WILL BE ADEQUATE TO GENERATE
SHOWERS AND THUNDERSTORMS. SO...WILL CARRY SLIGHT CHANCE TO CHANCE
POPS THROUGH MUCH OF THE REMAINDER OF THE FORECAST PERIOD.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* LIGHT EAST TO NORTHEAST WINDS.
* SHRA/TSRA POTENTIAL INCREASES OVERNIGHT INTO TOMORROW MORNING.
LENNING
//DISCUSSION...UPDATED 12Z...
ANOTHER LATE JUNE MORNING OF UNCLIMATOLOGICALLY FAVORED DENSE FOG
AND STRATUS OVER/NEAR THE TAF SITES. A LIGHT PRESSURE GRADIENT IN
PLACE UNDER HIGH PRESSURE HAS ALLOWED FOR THIS FOG AND
STRATUS...PARTLY ENHANCED AGAIN BY THE MARINE LAYER OFF COOL LAKE
MICHIGAN. THIS SHOULD DISSIPATE NEAR A SIMILAR TIME AS
YESTERDAY...AS THE STRATUS LAYER LOOKS TO BE FAIRLY SHALLOW.
ONSHORE FLOW WILL CONTINUE TODAY WITH A SLIGHT INCREASE TO NEAR 10
KT THIS AFTERNOON. THE CONTINUED ONSHORE FLOW THIS EVENING MAY
AGAIN BRING IN FOG OR STRATUS AFTER DARK. SOUTHERLY FLOW AND HIGH
CLOUDS MOVING IN TONIGHT ARE EXPECTED TO PREVENT THE FOG FROM
GETTING AS AGGRESSIVE AS THE PAST FEW DAYS. WARM AIR ADVECTION
TONIGHT AHEAD OF THE NEXT LOW PRESSURE SYSTEM SHOULD SPREAD SHOWERS
AND STORMS NORTHEAST TOWARD THE AREA. THESE MAY OVERSPREAD THE
TERMINALS PRIOR TO DAYBREAK. CONFIDENCE IS LOW OVERALL IN THAT TAF
ASPECT...BUT THINK MONDAY MORNING WILL AT LEAST SEE SHOWERS WITH
EMBEDDED THUNDER.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE ON WIND DIRECTION AND SPEEDS TODAY.
* MEDIUM CONFIDENCE ON SHRA/TSRA START TIME TONIGHT AND TOMORROW.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...TSRA LIKELY.
TUESDAY...CHANCE OF SHRA.
WEDNESDAY...SLIGHT CHANCE OF SHRA.
THURSDAY-SATURDAY...CHANCE OF SHRA AND SLIGHT CHANCE OF TSRA.
MTF
&&
.MARINE...
205 AM CDT
A LIGHT PRESSURE GRADIENT WILL BE SEEN OVER LAKE MICHIGAN TODAY DUE
TO EXPANSIVE HIGH PRESSURE CENTERED OVER THE EASTERN LAKES INTO NEW
ENGLAND. THIS REGIME OFFERS ONSHORE FLOW INTO ILLINOIS AND INDIANA
THAT SHOULD INCREASE TO AROUND 10 TO 15 KT DURING MIDDAY BEFORE
DIMINISHING BY SUNDOWN. THIS SETUP WILL ALSO ALLOW DENSE FOG TO
CONTINUE ACROSS MUCH OF THE LAKE AS THERE WILL BE LITTLE TURNOVER
OF THE MOIST AIRMASS OVER THE COOL WATERS. LOW PRESSURE WILL
APPROACH THE LAKE ON MONDAY AND EVENTUALLY MOVE OVER THE NORTHERN
PART OF IT MONDAY NIGHT. SOUTHERLY FLOW IS EXPECTED IN ADVANCE OF
THIS AND COULD PUSH THE FOG FURTHER NORTH ON MONDAY. IN
ADDITION...THUNDERSTORM CHANCES WILL INCREASE AND COULD DISRUPT
SOME OF THE FOG AS WELL. SO HAVE NOT EXTENDED THE DENSE FOG
ADVISORY ANY FURTHER THAN MONDAY MORNING AT THIS TIME...ALTHOUGH
FOR NORTHERN AND CENTRAL PORTIONS OF THE LAKE IT MAY NEED TO BE.
THE SYSTEM COLD FRONT WILL LIKELY PASS VERY EARLY TUESDAY MORNING
AND TURN WINDS WESTERLY. A SECOND COLD FRONT...MORE OF A BACKDOOR
ONE...IS ANTICIPATED TO PROGRESS SOUTHWARD TUESDAY NIGHT AND LEAD
TO NORTHERLY WINDS.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-
LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-
LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-
LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 10 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1005 AM CDT Sun Jun 22 2014
.DISCUSSION...
ISSUED 1005 AM CDT Sun Jun 22 2014
Convection developed just southwest of our CWA earlier this
morning, along the remnants of the outflow boundary from
yesterday`s storms. Latest surface map shows this boundary arcing
northwest along the Mississippi River then into central Iowa,
where a line of strong storms was moving through that area. Have
been seeing some increase in showers recently along this boundary
in the northeast corner of Missouri, and this should increase over
the next few hours. Latest RAP and HRRR guidance showing the
western CWA still with the best chances for showers/storms today,
with some more isolated activity across the east.
Have updated the zones/grids to reflect the storms mainly being
during the afternoon, as well as some adjustments to the sky
cover. Temperatures are largely in good shape and only required
some minor adjustments over the next few hours.
Geelhart
&&
.AVIATION...
ISSUED 651 AM CDT Sun Jun 22 2014
Weak high pressure over IL will provide light and variable winds
with light fog early this morning. Ground fog has generally
remained clear of the TAF sites, but is lingering in nearby fields
per surrounding observations. Will keep all TAF sites VFR this
morning as a result. Next concern is when storms will develop over
the next 24 hours. There remains a large spread in the model
guidance on storm initiation and coverage. The GFS remains the
most aggressive with storms later this afternoon and evening. The
00z NAM, Canadian, and ECMWF have slowed down the development of
storms until possibly later tonight, and mainly west of I-55. The
HRRR 3km model is still indicating a line of storms reaching near
the IL river by 00z this evening, but is the outlier of the latest
runs of the high res models. Will only include a VCSH later
tonight after 09z for now. Would not be surprised to see a pop-up
shower or storm late this afternoon and evening.
Winds will remain generally light and variable due to a weak
pressure gradient. Some southerly winds may develop for PIA and
SPI as the next shortwave aloft approaches IL this afternoon.
Wind speeds should remain less than 10kt at all terminal sites.
Shimon
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun Jun 22 2014
Though an area of showers and thunderstorms moved across much of
ILX yesterday evening, the air mass overall remains very much the
same. Hot and humid conditions persist. A weak frontal boundary
has meandered just north of the area and the next couple of
impulses are just to the west, lining up for arrival later today.
In between waves, much of this morning may be dry in most
locations. Not taking out the possibility for some very isolated
showers...but chances will increase this afternoon/later this
evening with the approach of the next wave. Surface low associated
with the next wave is weak and as a result, models are not doing
well with its evolution in the weak pattern as a whole. Models
continue to over produce the coverage of the convection, then
suffer the feedback issues. Chance/slight chance dominates, with
some minor adjustments for drier pds. Temps above normal and heat
indices in the 90s to wrap up the weekend until the next cool
front moves through Mon/Mon afternoon.
SHORT TERM...Today and tonight...
Hot. Humid. Heat indices into the mid 90s and chances of precip
increasing into the afternoon/evening hours. Waves to the west
showing varied paths and models connecting the dots on the qpf
leave a lot to be desired. Waves passing north and south remain a
possibility, but diurnal impacts and enhancement is just too
strong a possibility with leftover outflows in the region to NOT
have pops around this evening. Very similar tune to the trend from
the past few days. Coverage sporadic, plenty of ingredients to
work with, just non consistent triggers.
LONG TERM...Monday through Friday...
Upper trof/wave pushing through the region on Monday into Tuesday
bringing signif chance, increasing from Sun night into Monday
night. Models speeding up with initial arrival of boundary on
Monday, and slowing its departure...as this run has been a little
more diffuse with the pops and may see this trending with a +/- 12
hrs on either side. Not an absolute at this point, but
Monday/Monday night having the best chances at significant precip
through the fcst. A slightly cooler Tuesday through the end
of the week. Still warm, but potentially less humidity as winds
become more westerly on Tuesday, picking up a northerly component
by Wednesday. Forecast trending drier from late Tuesday through
Wednesday. Another wave Thursday brings back some pops ahead of
the next big storm system developing over the SW for late next
weekend.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
102 PM CDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 100 PM CDT SUN JUN 22 2014
SEVERE THUNDERSTORM WATCH IN EFFECT FOR MUCH OF THE DVN CWA UNTIL
7 PM THIS EVENING. LINE OF THUNDERSTORMS IN OUR NW CWA MOVING INTO
SBCAPES OF 3000-4000 J/KG. THIS LINE HAS ALREADY PRODUCED STRONG
WINDS AND ISOLATED HAIL ALONG WITH VERY HEAVY RAINFALL. HAD A
REPORT OF 2.40 INCHES OF RAIN IN BENTON COUNTY WITH THIS LINE.
OTHER STORMS WERE DEVELOPING IN SOUTHERN IA AND NORTHERN MO AND
WILL UPSCALE THIS AFTERNOON.
UPDATE ISSUED AT 1004 AM CDT SUN JUN 22 2014
HAVE INCREASED POPS WEST OF THE MS RIVER AS MCS CONTINUES TO MAKE
SLOW BUT STEADY PROGRESS ACROSS CENTRAL IA. PLENTY OF SUNSHINE IN
EASTERN IA AHEAD OF THE MCS WITH SBCAPES ALREADY NEARING 3000 J/KG
WITH DCAPE ALSO INCREASING. SPC HAS ADDED EASTERN IA TO A SLIGHT
RISK FOR THIS AFTERNOON WITH DAMAGING WIND THE MAIN THREAT WITH
MARGINAL SEVERE HAIL ALSO. STORMS WILL BE MOVING RATHER SLOWLY SO
TORRENTIAL RAINS WILL ALSO BE A CONCERN AS PRECIPITABLE WATERS
INCREASE TO OVER 1.50 INCHES. THERE WILL BE THE POTENTIAL FOR LOCALIZED
FLASH FLOODING ESPECIALLY WHERE HEAVY RAINS HAVE FALLEN IN THE
PAST WEEK.
&&
.SYNOPSIS...
ISSUED AT 249 AM CDT SUN JUN 22 2014
LATEST SFC ANALYSIS SHOWS SURFACE LOW OVER SOUTH CENTRAL NE WITH
A WEAK STATIONARY FRONT STRETCHING ACROSS NORTHERN SECTIONS OF THE
CWFA. DEW POINTS HOLDING IN THE 60S AND LIGHT WINDS IN THE FRONTAL
ZONE SUPPORTING FOG DEVELOPMENT ALONG HWY 20 CORRIDOR IN
PARTICULAR. ALOFT...NEAR ZONAL FLOW ACROSS THE CENTRAL US AT 500MB
WITH WEAK RIDGING OVER THE UPPER MISSISSIPPI VALLEY. FESTERING
WEAK CONVECTION VICINITY LSX AND MORE VIGOROUS STORMS OVER NW IA
CURRENTLY HEADED EAST-SOUTHEASTWARD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MAIN FORECAST CONCERN IN THE SHORT TERM IS POTENTIAL PRECIP TODAY.
RECENT MODEL SOLUTIONS REGARDING PRECIPITATION HAVE BEEN LARGELY
OVERDONE...THUS OVERALL CONFIDENCE IN SHORT TERM MODEL SOLUTIONS IS
LOWER THAN NORMAL. ECMWF FOR EXAMPLE GROSSLY OVERFORECAST FORCING
AND PRECIP YESTERDAY. THUS...FOR SHORT TERM WILL RELY ON BLEND OF
THIS MORNINGS MORE CONSERVATIVE HRRR...NAM...AND RUC.
STORMS CURRENTLY OVER NORTHWEST IA ARE HINTED AT BY HRRR AND RUC.
BOTH AGREE WITH WEAKENING TREND AS THE CONVECTION COMES UP AGAINST
THE UPPER RIDGE. GIVEN THIS EXPECTATION...THE MOST LIKELY
OPPORTUNITY FOR RAIN LOCALLY WILL COME THIS AFTERNOON AS THE UPPER
RIDGE SLIDES A BIT FARTHER EAST AND A SHORT WAVE PUSHES INTO WESTERN IA.
CONVECTION SHOULD FIRE IN CENTRAL IA AND PUSH EAST INTO WESTERN
SECTIONS OF THE CWFA THIS AFTERNOON. AS A RESULT...RAIN CHANCES
HAVE BEEN LOWERED ACROSS THE BOARD FOR THIS MORNING AND SHIFTED A
BIT WEST FOR THE AFTERNOON. PRECIP CHANCES WILL CONTINUE OVERNIGHT
AS WEAK CYCLONIC FLOW AND A STRONGER SHORT WAVE OVERTAKE THE
REGION.
DMD
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 249 AM CDT SUN JUN 22 2014
MONDAY INTO MONDAY EVENING STILL ON TRACK FOR BEST PCPN CHCS IN
NEXT FEW DAYS. MODELS CONTINUE TO DIVERGE ON WHETHER ANY PHASING
OCCURS BETWEEN SOUTHERN CANADA SHORTWAVE AND ENERGY RIPPLING IN
UNDERCUTTING QUASI-ZONAL FLOW... WITH MOST OF RECENT MODELS NOW
SHOWING NO PHASING. PHASING WILL HAVE SIGNIFICANT IMPACTS ON PCPN
AMOUNTS AND COVERAGE... AS MORE PHASED SCENARIO WOULD SUPPORT MCS
WITH WIDESPREAD HEAVIER RAINS OF 1-3+ INCHES. BUT... ATTIM THE
FCST IS TRENDING LOWER ON QPF AMOUNTS AND HARBORS SOME UNCERTAINTY
ON PCPN COVERAGE MONDAY INTO MONDAY EVENING GIVEN LACK OF PHASING
SUGGESTED BY MOST MODEL SOLUTIONS. THE CONCERN WITH NO PHASING IS
THE POTENTIAL FOR SOME OF AREA TO BE SPLIT BY BETTER COVERAGE WITH
ONE DISTURBANCE AND MORE CONCENTRATED BATCH OF CONVECTION LIFTING
NORTHEASTWARD INTO UPPER MIDWEST AND AWAY FROM CWA... WHILE
ANOTHER DISTURBANCE AND MORE ORGANIZED CONVECTION SHIFTS E/SE
ACROSS PORTIONS OF SOUTH CENTRAL PLAINS DIVING INTO BEST
INSTABILITY AND MOISTURE AXIS. WITH THAT BEING SAID... GIVEN HIGH
PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES AND DECENT UPPER
DIFFLUENCE WOULD ANTICIPATE STILL GOOD COVERAGE OF SHOWERS/STORMS
ON MONDAY WITH RISK OF LOCALLY HEAVY RAIN. PCPN SHOULD TAPER OFF
WEST TO EAST MONDAY EVENING WITH PASSAGE OF COLD FRONT.
TUE-TUE NIGHT... SLIGHTLY COOLER AND DRIER CONDITIONS APPEAR ON TAP
WITH WEAK SUBSIDENCE IN WAKE OF FRONT.
WED-SAT... PATTERN SET TO RETURN UNSETTLED/ACTIVE WITH SEVERAL
DISTURBANCES POSSIBLY IN QUASI-ZONAL FLOW BEFORE TRANSITION TO
SOUTHWEST FLOW ALOFT LATE IN THE PERIOD AHEAD OF WESTERN CONUS
TROUGH. SHOULD SEE A BIT OF AN UPTICK IN BOTH TEMPS AND HUMIDITY
BY LATE WEEK AND ESPECIALLY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 100 PM CDT SUN JUN 22 2014
VFR CONDS THROUGH THIS TAF CYCLE BUT MVFR/BRIEF IFR CONDS IN
THUNDERSTORMS. SCATTERED TO LINES OF THUNDERSTORMS THIS AFTERNOON
THEN MORE THUNDERSTORMS OVERNIGHT INTO MONDAY MORNING. SOUTH WINDS
LESS THAN 10 KNOTS BUT MUCH HIGHER IN THUNDERSTORMS.
&&
.HYDROLOGY...
ISSUED AT 249 AM CDT SUN JUN 22 2014
AREA TRIBUTARY RIVERS MAINLY NORTH OF I-80...AS WELL AS THE
MAINSTEM MISSISSIPPI RIVER WILL CONTINUE TO RISE INTO NEXT WEEK IN
RESPONSE TO RECENT HEAVY RAINFALL. THE POTENTIAL FOR LOCALLY HEAVY
RAINFALL EXISTS NEXT 36-48 HRS...WITH BEST CHANCES FOR PCPN AND
HEAVY RAINFALL LATE TONIGHT AND MONDAY. SOME GOOD NEWS THIS AM IN
THAT WHAT WAS LOOKING LIKE POTENTIAL FOR WIDESPREAD SIGNIFICANT
RAINFALL 1-3+ INCHES NOW MORE LOCALIZED POTENTIAL AS MODELS HAVE
GENERALLY BACKED OFF TO A WEAKER STORM SYSTEM IMPACTING THE AREA.
WOULD LIKE TO STRESS THAT WHILE THIS IS THE CASE THIS AM... THIS
IS FAR FROM CERTAIN AND COULD CHANGE AS MODELS CONTINUALLY
DIVERGING... THUS CAUTIOUS OPTIMISM THAT HIGHER QPF AMOUNTS MORE
LOCALIZED AND NOT AS WIDESPREAD. RIVER SITES THAT ARE CURRENTLY
UNDER A WARNING ARE FORECAST TO SEE MINOR TO MODERATE
FLOODING...WITH THE EXCEPTION OF THE MISSISSIPPI RIVER AT
BURLINGTON...WHERE MAJOR FLOODING IS FORECAST. HOWEVER...SHOULD
A HEAVY SOAKING RAIN OF 1 TO 3+ INCHES OCCUR OVER ANY RIVER BASINS
NEXT COUPLE OF DAYS...THEN RENEWED RISES AND HIGHER CREST LEVELS
WOULD BE LIKELY. THOSE WITH INTERESTS ON AREA RIVERS OR WHO
WOULD BE IMPACTED BY HIGH WATER LEVELS SHOULD PAY VERY CLOSE ATTENTION
NEXT COUPLE OF DAYS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...DMD
SHORT TERM...DMD
LONG TERM...05
AVIATION...HAASE
HYDROLOGY...05
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1259 PM MDT SUN JUN 22 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 1230 PM MDT SUN JUN 22 2014
THUNDERSTORM ACTIVITY EXPECTED TO RAMP UP QUICKLY AFTER 3 PM MDT
(4 PM CDT) AS A WEATHER DISTURBANCE IGNITES A FEW STORMS IN FAR
EASTERN COLORADO. AS THE DISTURBANCE MOVES EAST A LINE OF STRONG
TO SEVERE THUNDERSTORMS IS EXPECTED PRODUCING LARGE
HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. THE HRRR HAS
BEEN SLOWLY INCREASING THE WIND GUST POTENTIAL WITH THE LINE AND
WE COULD EXPERIENCE ANOTHER EPISODE OF 70+ MPH GUSTS. LOWS TONIGHT
IN THE MID 50S WEST...MID 60S EAST.
ON MONDAY MAY SEE SHOWERS AND THUNDERSTORMS IN THE LATE AFTERNOON
HOURS...PRIMARILY ACROSS FAR EASTERN COLORADO. OTHERWISE EXPECT
SOME CLOUDINESS WITH HIGHS IN THE MID 70S TO LOW 80S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 1242 PM MDT SUN JUN 22 2014
A FEW STORMS IN SOUTHEAST COLORADO MONDAY EVENING MAY SNEAK INTO
SOUTHWESTERN PARTS OF THE AREA...BUT BETTER CHANCES WILL BE AFTER
MIDNIGHT AS LLJ STRENGTHENS AND SHORTWAVE TROUGH COMES OUT OF THE
NORTHERN ROCKIES. STORMS MAY BE SLIGHTLY ELEVATED OVERNIGHT...WITH
PARCELS ORIGINATING AROUND 800MB HAVING UP TO 1000 J/KG OF
ELEVATED CAPE AND LITTLE TO NO CIN. LARGE HAIL WILL BE POSSIBLE
OVERNIGHT WITH THESE STORMS. SOME OF THIS ACTIVITY WILL LINGER
INTO TUESDAY MORNING...PARTICULARLY IN SOUTHWEST NEBRASKA...BEFORE
AFTERNOON CONVECTION GETS GOING IN NORTHEAST COLORADO WITH THE
NEXT SHORTWAVE. MODERATE INSTABILITY COMBINED WITH DEEP LAYER
SHEAR OF 30-40KTS SUGGEST ANOTHER ROUND OF SEVERE STORMS AS THEY
SLIDE ACROSS THE AREA TUESDAY EVENING. SOUTHEASTERLY SURFACE WINDS
CONTINUE ON WEDNESDAY WITH A CORRIDOR OF VERY UNSTABLE CONDITIONS
FORECAST BY THE AFTERNOON IN THE WESTERN HALF OF THE FORECAST
AREA. DEEP LAYER SHEAR HOWEVER IS SOMEWHAT WEAKER AT AROUND
30KTS...BUT SHOULD BE ADEQUATE FOR SEVERE STORMS AS NEXT SHORTWAVE
COMES OUT OF NORTHERN COLORADO IN THE AFTERNOON/EVENING.
A SUBTLE PATTERN CHANGE OCCURS IN THE LAST HALF OF THE LONG TERM
PERIOD WITH LONGWAVE TROUGH SETTLING INTO THE NORTHERN ROCKIES.
THE UPPER FLOW OVER THE CENTRAL PLAINS WILL BECOME SOUTHWEST.
SHORTWAVE TROUGHS ROTATING AROUND THE ROCKIES TROUGH OR EVEN THE
RIDGE OVER THE CENTRAL GULF WILL PROVIDE ENOUGH LIFT TO CONTINUE
THE MENTION OF DAILY THUNDERSTORM CHANCES.
TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE
LONG TERM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1120 AM MDT SUN JUN 22 2014
KGLD...VFR CONDITIONS EXPECTED THROUGH 00Z WITH NORTHEAST WINDS
AROUND 10KTS. IN THE 00Z-03Z TIME FRAME CURRENT INDICATIONS ARE
FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO IMPACT THE
TERMINAL WITH WIND GUSTS OVER 45 KTS POSSIBLE ALONG WITH LARGE
HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. AFTER 03Z
NORTHEAST WINDS GUSTING 15-20KTS WILL DECREASE TO 10KTS OR LESS
FROM THE NORTH/NORTHEAST.
KMCK...VFR CONDITIONS EXPECTED THROUGH 01Z WITH NORTHEAST WINDS
AROUND 10KTS INCREASING AND GUSTING NEAR 20KTS AFTER 22Z. FROM
02Z-05Z CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE
THUNDERSTORMS TO POSSIBLY IMPACT THE TERMINAL WITH WIND GUSTS TO
35KTS...POSSIBLY SOME SMALL HAIL AND HEAVY RAINFALL CREATING MVFR
CONDITIONS. THE STRONGER STORMS AND WINDS ARE CURRENTLY EXPECTED
TO BE SOUTH OF THE TERMINAL. AFTER 05Z NORTH TO NORTHEAST WINDS
UNDER 10KTS EXPECTED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...99
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1230 PM MDT SUN JUN 22 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 1230 PM MDT SUN JUN 22 2014
THUNDERSTORM ACTIVITY EXPECTED TO RAMP UP QUICKLY AFTER 3 PM MDT
(4 PM CDT) AS A WEATHER DISTURBANCE IGNITES A FEW STORMS IN FAR
EASTERN COLORADO. AS THE DISTURBANCE MOVES EAST A LINE OF STRONG
TO SEVERE THUNDERSTORMS IS EXPECTED PRODUCING LARGE
HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. THE HRRR HAS
BEEN SLOWLY INCREASING THE WIND GUST POTENTIAL WITH THE LINE AND
WE COULD EXPERIENCE ANOTHER EPISODE OF 70+ MPH GUSTS. LOWS TONIGHT
IN THE MID 50S WEST...MID 60S EAST.
ON MONDAY MAY SEE SHOWERS AND THUNDERSTORMS IN THE LATE AFTERNOON
HOURS...PRIMARILY ACROSS FAR EASTERN COLORADO. OTHERWISE EXPECT
SOME CLOUDINESS WITH HIGHS IN THE MID 70S TO LOW 80S.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 255 AM MDT SUN JUN 22 2014
MODELS ARE STILL SHOWING A VERY ACTIVE WEATHER PATTERN OVER THE CWA
THROUGH THE EXTENDED PERIOD. A WEAK...BROAD AND FLATTENING UPPER
LEVEL RIDGE WILL MOVE INTO THE CENTRAL PLAINS ON WEDNESDAY WITH
SEVERAL DISTURBANCES IN THE SOMEWHAT ZONAL FLOW. MODELS SEEM TO BE
IN DISAGREEMENT FROM THE VERY START AS THE ECMWF HAS A STRONG
SHORTWAVE TROUGH OVER THE SOUTH CENTRAL PLAINS ON WEDNESDAY AND THE
GFS BRINGS THE UPPER RIDGE FURTHER EAST INTO THE HIGH PLAINS.
THURSDAY INTO FRIDAY...AN UPPER LEVEL TROUGH WILL PUSH INTO THE
WESTERN UNITED STATES TRANSITIONING THE FLOW ALOFT TO A SOUTHWEST
FLOW. MODELS DISAGREE ONCE AGAIN WITH THE EVOLUTION OF THIS UPPER
TROUGH...WITH THE ECMWF DIGGING THE TROUGH FURTHER SOUTH INTO
ARIZONA AND NEW MEXICO CLOSING OFF INTO A LOW WHILE THE GFS KEEPS
THE UPPER TROUGH FURTHER NORTH AND SENDS A MORE POTENT SHORTWAVE
TROUGH THROUGH THE PLAINS ON SATURDAY. GIVEN THE MODEL
DISCREPANCIES...WENT AHEAD AND ACCEPTED THE ALLBLEND FOR
PRECIPITATION CHANCES WHICH ARE IN EVERYDAY OF THE EXTENDED.
SURFACE FEATURES ARE A LITTLE HARDER TO DETERMINE IN THE EXTENDED
GIVEN THE LARGE SCALE FEATURES CANNOT EVEN BE RESOLVED BY THE
MODELS. THE GFS STILL SHOWS A DRYLINE SETTING UP OVER THE CWA
THURSDAY NIGHT AND WAVERING OVER THE CWA THROUGH FRIDAY NIGHT. THIS
COULD SERVE AS A BOUNDARY FOR SEVERE THUNDERSTORM INITIATION
THURSDAY NIGHT THROUGH FRIDAY NIGHT. INSTABILITY...LOW LEVEL
MOISTURE...AND FAVORABLE SHEAR WILL BE PRESENT THROUGHOUT THE
EXTENDED AND...IF INTERACTING WITH THE FORCING OF THE DRYLINE...WILL
PROVIDE A GOOD ENVIRONMENT FOR SEVERE THUNDERSTORMS. HOWEVER...SINCE
MODELS ARE IN SUCH POOR AGREEMENT...WILL HOLD OFF ON GETTING
SPECIFIC IN TERMS OF TIMING AND POSITION OF SEVERE THUNDERSTORMS IN
THE EXTENDED.
TEMPERATURES IN THE EXTENDED WILL BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH HIGHS GENERALLY IN THE UPPER 80S TO LOW 90S AND LOWS IN
THE UPPER 50S WEST TO UPPER 60S AND LOW 70S EAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1120 AM MDT SUN JUN 22 2014
KGLD...VFR CONDITIONS EXPECTED THROUGH 00Z WITH NORTHEAST WINDS
AROUND 10KTS. IN THE 00Z-03Z TIME FRAME CURRENT INDICATIONS ARE
FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO IMPACT THE
TERMINAL WITH WIND GUSTS OVER 45 KTS POSSIBLE ALONG WITH LARGE
HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. AFTER 03Z
NORTHEAST WINDS GUSTING 15-20KTS WILL DECREASE TO 10KTS OR LESS
FROM THE NORTH/NORTHEAST.
KMCK...VFR CONDITIONS EXPECTED THROUGH 01Z WITH NORTHEAST WINDS
AROUND 10KTS INCREASING AND GUSTING NEAR 20KTS AFTER 22Z. FROM
02Z-05Z CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE
THUNDERSTORMS TO POSSIBLY IMPACT THE TERMINAL WITH WIND GUSTS TO
35KTS...POSSIBLY SOME SMALL HAIL AND HEAVY RAINFALL CREATING MVFR
CONDITIONS. THE STRONGER STORMS AND WINDS ARE CURRENTLY EXPECTED
TO BE SOUTH OF THE TERMINAL. AFTER 05Z NORTH TO NORTHEAST WINDS
UNDER 10KTS EXPECTED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...99
LONG TERM...ALW
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1120 AM MDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 1025 AM MDT SUN JUN 22 2014
HAVE REDONE THE FIRST AND SECOND PERIODS TO BETTER REFLECT CURRENT
OBSERVATIONS AND FINE TUNE TIMING AND AREAL COVERAGE OF
THUNDERSTORMS THIS AFTERNOON AND EVENING. FURTHER REVISIONS TO THE
FORECAST ARE POSSIBLE AS NEWER MODEL DATA COMES IN.
LATEST NAM/RUC/HRRR SUGGESTING SHOWER AND THUNDERSTORM ACTIVITY
WILL BEGIN AFTER 3 PM MDT (4 PM CDT) IN FAR EASTERN COLORADO
SPREADING EAST ACROSS THE REMAINDER OF THE AREA LATE THIS
AFTERNOON THROUGH THE EVENING BEFORE EXITING THE AREA
AROUND/SHORTLY AFTER MIDNIGHT. NAM IS IT A BIT QUICKER BRINGING
PRECIP INTO THE AREA COMPARED TO THE RUC/HRRR BUT BY 03Z ALL
MODELS IN PRETTY GOOD AGREEMENT WITH NUMEROUS SHOWERS AND
THUNDERSTORMS IN WESTERN KANSAS AND SOUTHWEST NEBRASKA. HRRR
SUGGESTING A LINE OF STORMS WILL MOVE THROUGH WITH THE POTENTIAL
FOR LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. HAVE
TRENDED TOWARD THE HRRR AND NAM FOR POP PLACEMENT.
HIGHS IN THE 80S EXCEPT LOW 90S FROM NORTON TO HILL CITY TO LEOTI
AND POINTS EAST.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 255 AM MDT SUN JUN 22 2014
UPPER FLOW WILL BE ZONAL TODAY AND TONIGHT TURNING NORTHWESTERLY
MONDAY AND TUESDAY. ZONAL FLOW RETURNS TUESDAY NIGHT. A SURFACE
TROUGH WILL BE ACROSS NORTHWEST KANSAS TODAY. BY THIS AFTERNOON A
FRONT WILL PUSH SOUTH ACROSS NORTHWEST KANSAS. HIGH PRESSURE WILL
MOVE INTO THE CENTRAL PLAINS TONIGHT AND CONTINUE THROUGH TUESDAY
NIGHT.
A SHORTWAVE MOVES EAST OF THE ROCKIES THIS AFTERNOON AND EVENING.
THERE IS GOOD LIFT ASSOCIATED WITH THE SHORTWAVE. CAPE RANGES FROM
1800 TO 2400 J/KG AND SHEAR VALUES ARE FROM 35 TO 40 KTS.
PRECIPITABLE WATER IS JUST OVER AN INCH ACROSS THE FA. MODELS HAVE
CONSISTENTLY SHOWED HIGHER QPF GENERALLY ALIGNED ALONG AND SOUTH OF
THE TROUGH AXIS. THE GFS HAS UNUSUALLY LARGE QPF BUT IT IS WELL
SOUTH OF THE FA. STORM MOVEMENT RANGES FROM 10 TO 15 KTS BUT IS NOT
FAVORABLE TO TRAINING STORMS DUE TO A PERPENDICULAR ORIENTATION TO
THE TROUGH AXIS. PLAN TO CONTINUE HIGH POPS AND WORDING FOR POSSIBLE
HEAVY RAINFALL SUNDAY AFTERNOON AND EVENING. CHANCES DECREASE
OVERNIGHT. SUBSIDENCE WILL KEEP CONDITIONS DRY MONDAY MORNING, BUT
BY AFTERNOON EXPECT THUNDERSTORMS TO DEVELOP OVER HIGHER TERRAIN IN
COLORADO DUE TO UPSLOPE CONVERGENCE IN THAT AREA. STORMS WILL DRIFT
EAST DURING THE AFTERNOON AND EVENING. PLAN TO GO WITH SLIGHT CHANCE
POPS MONDAY AFTERNOON WITH CHANCE POPS MONDAY EVENING. A SIMILAR
SCENARIO EXISTS FOR TUESDAY WITH STORMS INITIATING OVER THE HIGHER
TERRAIN TO THE WEST AND MOVING EAST INTO THE FA. PLAN TO CONTINUE
CHANCE POPS FOR TUESDAY/TUESDAY NIGHT.
MAX TEMPERATURES WILL RANGE FROM THE MID 80S TO 90 TODAY. COOLER
READINGS WILL BE REACHED IN THE UPPER 70S TO LOWER 80S ON MONDAY.
MAX TEMPERATURES TUESDAY SHOULD REACH THE LOWER TO MID 80S. MIN
TEMPERATURES WILL RANGE FROM THE UPPER 50S TO LOWER 60S WITH LOWER
TO MID 60S TUESDAY NIGHT.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 255 AM MDT SUN JUN 22 2014
MODELS ARE STILL SHOWING A VERY ACTIVE WEATHER PATTERN OVER THE CWA
THROUGH THE EXTENDED PERIOD. A WEAK...BROAD AND FLATTENING UPPER
LEVEL RIDGE WILL MOVE INTO THE CENTRAL PLAINS ON WEDNESDAY WITH
SEVERAL DISTURBANCES IN THE SOMEWHAT ZONAL FLOW. MODELS SEEM TO BE
IN DISAGREEMENT FROM THE VERY START AS THE ECMWF HAS A STRONG
SHORTWAVE TROUGH OVER THE SOUTH CENTRAL PLAINS ON WEDNESDAY AND THE
GFS BRINGS THE UPPER RIDGE FURTHER EAST INTO THE HIGH PLAINS.
THURSDAY INTO FRIDAY...AN UPPER LEVEL TROUGH WILL PUSH INTO THE
WESTERN UNITED STATES TRANSITIONING THE FLOW ALOFT TO A SOUTHWEST
FLOW. MODELS DISAGREE ONCE AGAIN WITH THE EVOLUTION OF THIS UPPER
TROUGH...WITH THE ECMWF DIGGING THE TROUGH FURTHER SOUTH INTO
ARIZONA AND NEW MEXICO CLOSING OFF INTO A LOW WHILE THE GFS KEEPS
THE UPPER TROUGH FURTHER NORTH AND SENDS A MORE POTENT SHORTWAVE
TROUGH THROUGH THE PLAINS ON SATURDAY. GIVEN THE MODEL
DISCREPANCIES...WENT AHEAD AND ACCEPTED THE ALLBLEND FOR
PRECIPITATION CHANCES WHICH ARE IN EVERYDAY OF THE EXTENDED.
SURFACE FEATURES ARE A LITTLE HARDER TO DETERMINE IN THE EXTENDED
GIVEN THE LARGE SCALE FEATURES CANNOT EVEN BE RESOLVED BY THE
MODELS. THE GFS STILL SHOWS A DRYLINE SETTING UP OVER THE CWA
THURSDAY NIGHT AND WAVERING OVER THE CWA THROUGH FRIDAY NIGHT. THIS
COULD SERVE AS A BOUNDARY FOR SEVERE THUNDERSTORM INITIATION
THURSDAY NIGHT THROUGH FRIDAY NIGHT. INSTABILITY...LOW LEVEL
MOISTURE...AND FAVORABLE SHEAR WILL BE PRESENT THROUGHOUT THE
EXTENDED AND...IF INTERACTING WITH THE FORCING OF THE DRYLINE...WILL
PROVIDE A GOOD ENVIRONMENT FOR SEVERE THUNDERSTORMS. HOWEVER...SINCE
MODELS ARE IN SUCH POOR AGREEMENT...WILL HOLD OFF ON GETTING
SPECIFIC IN TERMS OF TIMING AND POSITION OF SEVERE THUNDERSTORMS IN
THE EXTENDED.
TEMPERATURES IN THE EXTENDED WILL BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH HIGHS GENERALLY IN THE UPPER 80S TO LOW 90S AND LOWS IN
THE UPPER 50S WEST TO UPPER 60S AND LOW 70S EAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1120 AM MDT SUN JUN 22 2014
KGLD...VFR CONDITIONS EXPECTED THROUGH 00Z WITH NORTHEAST WINDS
AROUND 10KTS. IN THE 00Z-03Z TIME FRAME CURRENT INDICATIONS ARE
FOR A LINE OF STRONG TO SEVERE THUNDERSTORMS TO IMPACT THE
TERMINAL WITH WIND GUSTS OVER 45 KTS POSSIBLE ALONG WITH LARGE
HAIL AND HEAVY RAINFALL CREATING MVFR CONDITIONS. AFTER 03Z
NORTHEAST WINDS GUSTING 15-20KTS WILL DECREASE TO 10KTS OR LESS
FROM THE NORTH/NORTHEAST.
KMCK...VFR CONDITIONS EXPECTED THROUGH 01Z WITH NORTHEAST WINDS
AROUND 10KTS INCREASING AND GUSTING NEAR 20KTS AFTER 22Z. FROM
02Z-05Z CURRENT INDICATIONS ARE FOR A LINE OF STRONG TO SEVERE
THUNDERSTORMS TO POSSIBLY IMPACT THE TERMINAL WITH WIND GUSTS TO
35KTS...POSSIBLY SOME SMALL HAIL AND HEAVY RAINFALL CREATING MVFR
CONDITIONS. THE STRONGER STORMS AND WINDS ARE CURRENTLY EXPECTED
TO BE SOUTH OF THE TERMINAL. AFTER 05Z NORTH TO NORTHEAST WINDS
UNDER 10KTS EXPECTED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...99
SHORT TERM...FS
LONG TERM...ALW
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1025 AM MDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 1025 AM MDT SUN JUN 22 2014
HAVE REDONE THE FIRST AND SECOND PERIODS TO BETTER REFLECT CURRENT
OBSERVATIONS AND FINE TUNE TIMING AND AREAL COVERAGE OF
THUNDERSTORMS THIS AFTERNOON AND EVENING. FURTHER REVISIONS TO THE
FORECAST ARE POSSIBLE AS NEWER MODEL DATA COMES IN.
LATEST NAM/RUC/HRRR SUGGESTING SHOWER AND THUNDERSTORM ACTIVITY
WILL BEGIN AFTER 3 PM MDT (4 PM CDT) IN FAR EASTERN COLORADO
SPREADING EAST ACROSS THE REMAINDER OF THE AREA LATE THIS
AFTERNOON THROUGH THE EVENING BEFORE EXITING THE AREA
AROUND/SHORTLY AFTER MIDNIGHT. NAM IS IT A BIT QUICKER BRINGING
PRECIP INTO THE AREA COMPARED TO THE RUC/HRRR BUT BY 03Z ALL
MODELS IN PRETTY GOOD AGREEMENT WITH NUMEROUS SHOWERS AND
THUNDERSTORMS IN WESTERN KANSAS AND SOUTHWEST NEBRASKA. HRRR
SUGGESTING A LINE OF STORMS WILL MOVE THROUGH WITH THE POTENTIAL
FOR LARGE HAIL...DAMAGING WINDS AND LOCALLY HEAVY RAINFALL. HAVE
TRENDED TOWARD THE HRRR AND NAM FOR POP PLACEMENT.
HIGHS IN THE 80S EXCEPT LOW 90S FROM NORTON TO HILL CITY TO LEOTI
AND POINTS EAST.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 255 AM MDT SUN JUN 22 2014
UPPER FLOW WILL BE ZONAL TODAY AND TONIGHT TURNING NORTHWESTERLY
MONDAY AND TUESDAY. ZONAL FLOW RETURNS TUESDAY NIGHT. A SURFACE
TROUGH WILL BE ACROSS NORTHWEST KANSAS TODAY. BY THIS AFTERNOON A
FRONT WILL PUSH SOUTH ACROSS NORTHWEST KANSAS. HIGH PRESSURE WILL
MOVE INTO THE CENTRAL PLAINS TONIGHT AND CONTINUE THROUGH TUESDAY
NIGHT.
A SHORTWAVE MOVES EAST OF THE ROCKIES THIS AFTERNOON AND EVENING.
THERE IS GOOD LIFT ASSOCIATED WITH THE SHORTWAVE. CAPE RANGES FROM
1800 TO 2400 J/KG AND SHEAR VALUES ARE FROM 35 TO 40 KTS.
PRECIPITABLE WATER IS JUST OVER AN INCH ACROSS THE FA. MODELS HAVE
CONSISTENTLY SHOWED HIGHER QPF GENERALLY ALIGNED ALONG AND SOUTH OF
THE TROUGH AXIS. THE GFS HAS UNUSUALLY LARGE QPF BUT IT IS WELL
SOUTH OF THE FA. STORM MOVEMENT RANGES FROM 10 TO 15 KTS BUT IS NOT
FAVORABLE TO TRAINING STORMS DUE TO A PERPENDICULAR ORIENTATION TO
THE TROUGH AXIS. PLAN TO CONTINUE HIGH POPS AND WORDING FOR POSSIBLE
HEAVY RAINFALL SUNDAY AFTERNOON AND EVENING. CHANCES DECREASE
OVERNIGHT. SUBSIDENCE WILL KEEP CONDITIONS DRY MONDAY MORNING, BUT
BY AFTERNOON EXPECT THUNDERSTORMS TO DEVELOP OVER HIGHER TERRAIN IN
COLORADO DUE TO UPSLOPE CONVERGENCE IN THAT AREA. STORMS WILL DRIFT
EAST DURING THE AFTERNOON AND EVENING. PLAN TO GO WITH SLIGHT CHANCE
POPS MONDAY AFTERNOON WITH CHANCE POPS MONDAY EVENING. A SIMILAR
SCENARIO EXISTS FOR TUESDAY WITH STORMS INITIATING OVER THE HIGHER
TERRAIN TO THE WEST AND MOVING EAST INTO THE FA. PLAN TO CONTINUE
CHANCE POPS FOR TUESDAY/TUESDAY NIGHT.
MAX TEMPERATURES WILL RANGE FROM THE MID 80S TO 90 TODAY. COOLER
READINGS WILL BE REACHED IN THE UPPER 70S TO LOWER 80S ON MONDAY.
MAX TEMPERATURES TUESDAY SHOULD REACH THE LOWER TO MID 80S. MIN
TEMPERATURES WILL RANGE FROM THE UPPER 50S TO LOWER 60S WITH LOWER
TO MID 60S TUESDAY NIGHT.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 255 AM MDT SUN JUN 22 2014
MODELS ARE STILL SHOWING A VERY ACTIVE WEATHER PATTERN OVER THE CWA
THROUGH THE EXTENDED PERIOD. A WEAK...BROAD AND FLATTENING UPPER
LEVEL RIDGE WILL MOVE INTO THE CENTRAL PLAINS ON WEDNESDAY WITH
SEVERAL DISTURBANCES IN THE SOMEWHAT ZONAL FLOW. MODELS SEEM TO BE
IN DISAGREEMENT FROM THE VERY START AS THE ECMWF HAS A STRONG
SHORTWAVE TROUGH OVER THE SOUTH CENTRAL PLAINS ON WEDNESDAY AND THE
GFS BRINGS THE UPPER RIDGE FURTHER EAST INTO THE HIGH PLAINS.
THURSDAY INTO FRIDAY...AN UPPER LEVEL TROUGH WILL PUSH INTO THE
WESTERN UNITED STATES TRANSITIONING THE FLOW ALOFT TO A SOUTHWEST
FLOW. MODELS DISAGREE ONCE AGAIN WITH THE EVOLUTION OF THIS UPPER
TROUGH...WITH THE ECMWF DIGGING THE TROUGH FURTHER SOUTH INTO
ARIZONA AND NEW MEXICO CLOSING OFF INTO A LOW WHILE THE GFS KEEPS
THE UPPER TROUGH FURTHER NORTH AND SENDS A MORE POTENT SHORTWAVE
TROUGH THROUGH THE PLAINS ON SATURDAY. GIVEN THE MODEL
DISCREPANCIES...WENT AHEAD AND ACCEPTED THE ALLBLEND FOR
PRECIPITATION CHANCES WHICH ARE IN EVERYDAY OF THE EXTENDED.
SURFACE FEATURES ARE A LITTLE HARDER TO DETERMINE IN THE EXTENDED
GIVEN THE LARGE SCALE FEATURES CANNOT EVEN BE RESOLVED BY THE
MODELS. THE GFS STILL SHOWS A DRYLINE SETTING UP OVER THE CWA
THURSDAY NIGHT AND WAVERING OVER THE CWA THROUGH FRIDAY NIGHT. THIS
COULD SERVE AS A BOUNDARY FOR SEVERE THUNDERSTORM INITIATION
THURSDAY NIGHT THROUGH FRIDAY NIGHT. INSTABILITY...LOW LEVEL
MOISTURE...AND FAVORABLE SHEAR WILL BE PRESENT THROUGHOUT THE
EXTENDED AND...IF INTERACTING WITH THE FORCING OF THE DRYLINE...WILL
PROVIDE A GOOD ENVIRONMENT FOR SEVERE THUNDERSTORMS. HOWEVER...SINCE
MODELS ARE IN SUCH POOR AGREEMENT...WILL HOLD OFF ON GETTING
SPECIFIC IN TERMS OF TIMING AND POSITION OF SEVERE THUNDERSTORMS IN
THE EXTENDED.
TEMPERATURES IN THE EXTENDED WILL BE NEAR NORMAL TO SLIGHTLY ABOVE
NORMAL WITH HIGHS GENERALLY IN THE UPPER 80S TO LOW 90S AND LOWS IN
THE UPPER 50S WEST TO UPPER 60S AND LOW 70S EAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 525 AM MDT SUN JUN 22 2014
VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK UNTIL LATE AFTERNOON
AND EVENING. A DISTURBANCE WILL INITIATE THUNDERSTORMS ALONG A
TROUGH AXIS IN NORTHWEST KANSAS THIS AFTERNOON. SOME BRIEF MVFR
CONDITIONS ARE POSSIBLE NEAR STORMS. A FRONT WILL MOVE SOUTH INTO
NORTHWEST KANSAS PRODUCING BREEZY CONDITIONS LATE THIS AFTERNOON
AND EVENING. THUNDERSTORMS SHOULD GRADUALLY END LATE THIS EVENING.
FORECAST SOUNDINGS INDICATE LOW CIGS AND MVFR RETURNING TO BOTH
TERMINALS EARLY MONDAY MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...99
SHORT TERM...FS
LONG TERM...ALW
AVIATION...FS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
145 PM EDT SUN JUN 22 2014
.SYNOPSIS...
ISSUED AT 314 AM EDT SUN JUN 22 2014
NORTHERN MICHIGAN WILL REMAIN BETWEEN HIGH PRESSURE SINKING INTO
THE EASTERN GREAT LAKES TODAY...AND LOW PRESSURE OVER THE UPPER
MISSISSIPPI VALLEY. THERE WILL BE A FEW SHOWERS THIS MORNING...BUT A
BETTER SHOT OF SHOWERS AND THUNDERSTORMS...WILL ARRIVE LATER MONDAY
AND MONDAY NIGHT.
&&
.UPDATE...
ISSUED AT 1100 AM EDT SUN JUN 22 2014
AS REFERENCED IN THE EARLY MORNING DISCUSSION...ONE OF THE MAIN
FORECAST QUESTIONS FOR THIS AFTERNOON /IN AN OTHERWISE NEBULOUS
WEATHER REGIME/ IS WHETHER A FEW SHOWERS CAN POP THIS AFTERNOON
OVER INLAND AREAS OF NRN LOWER.
LARGE SCALE FORCING FOR ASCENT REMAINS WEAK...WITH H5 RIDGING
OVERHEAD AND LOWER LEVEL WEAK H8 THETA-E ADVECTION. MEANWHILE...
SURFACE PRESSURE PATTERN IS VERY WEAK/NONDESCRIPT. THIS WILL ALLOW
LAKE BREEZES TO EVOLVE WITH DAYTIME HEATING...WITH GENERAL
CONVERGENCE OVER INTERIOR /HIGHER TERRAIN/ AREAS. THOUGH 12Z APX
SOUNDING SHOWED A WEAK CAP NEAR H6 /BASED ON LIFTING A 76/56
PARCEL/ AM INCLINED TO INCLUDE ISOLATED LIGHT SHOWERS AFTER 18Z
FOR INTERIOR AREAS. DECISION BASED IN LARGE PART ON MORNING
VISIBLE SATELLITE TRENDS...WHICH SHOWS PERSISTENT LOW CLOUDS OVER
NW LOWER FROM TVC-FKS-MBL...MID CLOUDS OVER NE LOWER...AND
RELATIVELY SUNNY SKIES ALONG THE US-131/US-127 CORRIDORS. THIS
LATE MORNING DIFFERENTIAL HEATING REGIME /ALREADY SHOWN IN SURFACE
WINDS/ MAY BE JUST ENOUGH TO TIP SCALES IN FAVOR OF A FEW SHOWERS.
ONLY A 20 PERCENT CHANCE...AND ANY SHOWER THAT DEVELOPS SHOULD BE
BRIEF...THOUGH CELLS WILL BE SLOW MOVING.
OTHERWISE...A PARTLY SUNNY AFTERNOON IS EXPECTED WITH HIGHS AWAY
FROM THE BIG LAKES IN THE 70S.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 314 AM EDT SUN JUN 22 2014
...SOME SPOTTY SHOWERS THIS MORNING...
HIGH IMPACT WEATHER POTENTIAL: PATCHY FOG DEVELOPING AFTER MIDNIGHT
SUNDAY NIGHT/MONDAY MORNING.
PATTERN SUMMARY/IMPLICATIONS: VERY SIMILAR STORY TO WHAT WE
DISCUSSED 24 HOURS AGO WITH CLOSED LOW SITTING OVER
MANITOBA/SASKATCHEWAN WITH DOWNSTREAM RIDGING OVER MICHIGAN NORTH
INTO ONTARIO SQUEEZED AGAINST LARGER SCALE TROUGHING OVER EASTERN
CANADA. SHORTWAVES CONTINUE TO SHEAR OUT AS THEY RUN INTO THE
OVERHEAD RIDGE AXIS...WITH THE MOST RECENT WAVE OF DEEP MOISTURE NOW
BEGINNING TO PULL EAST OF THE STATE. DRILLING DOWN TO THE SURFACE
ALSO REVEALS STRONG SIMILARITY TO ONE DAY AGO WITH HIGH PRESSURE
ANCHORED OVER HUDSON BAY AND A SURFACE LOW BENEATH THE CLOSE FEATURE
OVER MANITOBA. BETWEEN THESE FEATURES...A PLUME OF DEEPER MOISTURE
REMAINS STALLED OVER NORTHERN MICHIGAN. WEAK POSITIVE THETAE
ADVECTION AT H8 CONTINUES TO FORCE SHRAS PRIMARILY OVER THE
NORTHEASTERN HALF OF THE CWA. GIVEN THE STAGNANT NATURE OF THE
PATTERN...FORECAST CHALLENGES WILL CONTINUE TO REVOLVE AROUND LIGHT
PRECIPITATION POTENTIAL WITH ASSOCIATED CLOUDS/IMPACTS ON
TEMPERATURES.
TODAY...
PRECIPITATION CHANCES: OVERHEAD H8 THETAE GRADIENT STALLS OVER
EASTERN CHIP/MACK SOUTH AND EAST ACROSS NORTHEAST LOWER THROUGH NOON
BEFORE BEING PUSHED NORTH AND EAST. WITH DEEP MOISTURE WANING /SEE
CURRENT WV IMAGERY/...EXPECT COVERAGE IN SHOWER ACTIVITY ASSOCIATED
WITH THIS GRADIENT TO WEAKEN...BUT LIKELY NOT QUIT THROUGH THE
MORNING HOURS...WARRANTING A CHANCE POP/SCATTERED WORDING HERE. AS
WE LOOK INTO THE AFTERNOON...FOCUS TURNS TO POPPING ANY DIURNAL
CONVECTION WITH A SOMEWHAT MOISTER LLEVEL AIRMASS THAN 24 HOURS
PREVIOUS. STILL THINK THE NAM IS TOO ROBUST WITH LLEVEL
MOISTURE...BUT EVEN THE FAR MORE CONSERVATIVE RAP ALLOWS FOR 500-750
JOULES OF MUCAPE DEVELOPMENT OVER THE HIGH TERRAIN OF INTERIOR
NORTHERN LOWER. QG FORCING FOR ASCENT IS NIL OVERHEAD WITH SLOWLY
BUILDING HEIGHTS ALOFT REQUIRING LAKE BREEZES/UPSLOPE CONVERGENCE TO
PUSH US TO CONVECTIVE INITIATION. HAVE TROUBLE BELIEVING WE CAN GET
AROUND MODEST CAPPING NEAR H7 PURELY WITH BOUNDARY LAYER PROCESSES.
THUS...WILL MAINTAIN GOING DRY FORECAST FOR THE AFTERNOON HOURS.
QPF: BASIN WIDE AMOUNTS VERY LIGHT...LESS THAN 0.05". ISOLATED
LOCATIONS COULD RECEIVE NEAR 0.20" GIVEN MODEST PWATS/WARM CLOUD
DEPTHS AND LIGHT STEERING FLOW.
TEMPERATURES: T8S NEAR +12C AT 00Z WITH CONTINUED SLOW WARMING
THROUGH TODAY SUGGESTS WE SHOULD BE ABLE TO BEST YESTERDAYS HIGHS
AND GUIDANCE CONSENSUS HANDLES THIS WELL...WITH MID/UPPER 70S INLAND
AND CLOSER TO 70 AT THE LAKE-BREEZE COOLED COASTS.
WINDS: CONTINUED LIGHT GRADIENT FAVORS ROBUST LAKE BREEZE
DEVELOPMENT THIS AFTERNOON.
TONIGHT...
PRECIPITATION CHANCES: WITH NO HELPFUL LLEVEL MOISTURE
ADVECTION...CHANCES WILL BE CONTINGENT ON AFTERNOON ACTIVITY
PERSISTING INTO THE EVENING. GIVEN THE CURRENT EXPECTATION THAT
WE/LL REMAIN SHOWER FREE THROUGH THE AFTERNOON...WILL MAINTAIN DRY
CONDITIONS THROUGH THE TONIGHT PERIOD AS WELL.
QPF: NIL.
TEMPERATURES: WILL STICK NEAR GUIDANCE CONSENSUS IN THE MID 50S AS
PARTLY CLOUDY SKIES SHOULD ALLOW FOR MODEST RADIATIONAL COOLING WITH
GEOSTROPHIC FLOW AT 1000MB NEAR 10KTS LIKELY STILL ALLOW MOST
LOCATIONS TO DECOUPLE.
WINDS: CALM OR LIGHT DRAINAGE FLOWS EXPECTED.
FOG: WITH MID/UPPER LEVEL MOISTURE BEGINNING TO PULL EAST...CAN SEE
SOME INCREASED FOG POTENTIAL AS LLEVEL FLOW GAINS A SOUTHWESTERLY
COMPONENT WITH CONTINUED WEAK LLEVEL MOISTURE ADVECTION AND ENOUGH
CLEARING FOR RADIATIONAL COOLING IN THE PRESENCE OF ELEVATED 2M
DEWPOINTS. WILL ADD PATCHY FOG TO THE FORECAST AFTER MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 314 AM EDT SUN JUN 22 2014
...SCATTERED THUNDERSTORMS MONDAY AND MONDAY NIGHT...
IMPACTS: MINIMAL. SEVERE STORMS STILL LOOK UNLIKELY.
SYNOPTIC PATTERN/EVOLUTION:
THE ENTIRE FORECAST PERIOD OF MONDAY THROUGH THE NEXT WEEKEND WILL
SEE A SHALLOW AND PROGRESSIVE MID LEVEL AMPLITUDE PATTERN THROUGH A
GOOD CHUNK OF THE WORK WEEK. THEN...HEIGHTS RISE OVER THE HEART OF
THE COUNTRY...INCLUDING THE WESTERN GREAT LAKES. THIS IS IN RESPONSE
TO TWO LARGE UPPER/CLOSED LOWS DROPPING INTO THE PAC NW/NEW ENGLAND.
AN INCREASINGLY MUGGIER AIR MASS MONDAY AND EARLY TUESDAY...AHEAD OF
AN APPROACHING AREA OF LOW PRESSURE AND PRECIPITATION...WILL GET
COOLED AND DRIED DOWN LATER TUESDAY THROUGH WEDNESDAY. TEMPERATURES
WILL START RISING BACK UP AGAIN FOR LATE IN THE WORK WEEK.
PRECIPITATION CHANCES AFTER EARLY TUESDAY DO NOT LOOK ALL THAT
FANTASTIC.
MON-TUES:
THE BEST ACTION RESIDES IN THIS TIME FRAME. SHALLOW RIDGING EXITS
EAST...WHILE AN ELONGATED UPPER TROUGH AXIS ACROSS ONTARIO BACKS
WINDS ALOFT WSW. SHORTWAVE ENERGY AND AN ASSOCIATED SFC LOW WILL
LIFT UP ACROSS NRN MICHIGAN. THIS LOW PRESSURE DOESN`T LOOK ALL THAT
IMPRESSIVE...BUT A WARM FRONT WILL EDGE UP THROUGH MUCH OF NRN
LOWER...WITH THE TRAILING COLD FRONT EXITING NEAR TUESDAY MORNING.
AS THE SFC LOW DEPARTS...ANOTHER COLD FRONT...ONE WITH MORE
REFRESHING AIR...WILL SLIDE SOUTHWARD THROUGH NRN MICHIGAN BY OVER
NIGHT TUESDAY NIGHT (UNCERTAINTY ON EXACT TIMING). COULD SEE SOME
SHOWERS POSSIBLY SNEAKING INTO A FEW SECTIONS OF NW LOWER MONDAY
MORNING...AND ALSO SOME POTENTIAL CONVECTIVE DEBRIS FROM FURTHER
WEST...BUT THE USING AN EXPECTED AVERAGE PARCEL OF 80/61 (DEW
POINT IS SOME QUESTION)...CAN POSSIBLY GLEAN 1000-1300 J/KG MONDAY
LATE AFTERNOON. RIGHT WITH THE WARM FRONTAL ARRIVAL. THE LOW TRACKS
OVER NRN MICHIGAN WITH MAINLY NRN LOWER SNEAKING INTO THE WARM
SECTOR FOR THE EVENING (TIMING ALSO IN SOME QUESTION). SHOWER AND
STORM CHANCES WILL BE GREATEST MONDAY NIGHT...AND ALTHOUGH NOTHING
OVERLY IMPRESSIVE...WILL HAVE TO WATCH THE DEVELOPMENTS SURROUNDING
WIND FIELDS AND INSTABILITY. THERE IS A TIGHTENING IN THE MID LEVEL
FLOW (40KTS)...AND IF THE INSTABILITY ABOVE CAN BE HAD...AND BEING
IN THE WARM SECTOR...WHILE EASTERN UPPER GETS GARDEN VARIETY SHOWERS
AND A FEW STORMS...NRN LOWER COULD SEE STRONGER CELLS. CELLS THAT
WILL BE IN A BETTER ENVIRONMENT FOR GUSTY WINDS/SMALLISH HAIL AND
THE POSSIBILITY OF A ROGUE TORNADO. THAT`S AN AWFUL LOT OF IF`S
THOUGH. AFTER THE LOW DEPARTS...AND SECONDARY COOL FRONT GETS
DROPPED THROUGH US...WITH MINIMAL FORCING...DIMINISHING MOISTURE AND
A TOTAL LACK OF INSTABILITY DUE TO MORE OF A COL AREA IN STORE FOR
US. HIGHS WELL INTO THE 70S MONDAY WILL START COOLING OFF...WITH
HIGHS TUESDAY IN THE UPPER 60S/70F IN EASTERN UPPER...AND UPPER 70S
NEARER SAGINAW BAY.
WEDNESDAY THROUGH NEXT WEEKEND:
AN EVEN COOLER DAY WEDNESDAY WITH HIGHS IN THE MAINLY IN THE 60S...A
FEW LOWER 70S...AS HIGH PRESSURE SLIPS INTO OUR NECK OF THE WOODS
FROM ONTARIO. SHOULD BE A BEAUTIFUL DAY. THERE ARE DEFINITE HINTS AT
SOME SHORTWAVE ACTIVITY TRACKING THROUGH US THURSDAY/THURSDAY NIGHT
FOR RAIN SHOWER CHANCES...BEFORE MID LEVEL HEIGHTS RISES BEGIN
FRIDAY AND CONTINUE INTO THE WEEKEND FOR A RETURN TO MIDDLE 70S TO
LOWER 80S TEMPS. EARLY HINTS ARE FOR NO PRECIPITATION NEXT WEEKEND
WITH ALL THE HEAT AND INSTABILITY RESIDING TO OUR WEST AND SOUTH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 139 PM EDT SUN JUN 22 2014
WEAK HIGH PRESSURE OVER THE ERN GREAT LAKES WILL PROVIDE NRN MI
WITH CONTINUED VFR WEATHER CONDITIONS THIS AFTERNOON INTO THIS
EVENING...WITH ONLY SCATTERED CU AND PATCHES OF MID LEVEL AC
EXPECTED. WINDS WILL REMAIN LIGHT...WITH GENERAL ONSHORE LAKE
BREEZES ANTICIAPTED. SOME PATCHY IFR/MVFR FOG WILL DEVELOP AFTER
MIDNIGHT TONIGHT WITH LIGHT WINDS...PARTLY CLOUDY SKIES...AND
INCREASING LOW LEVEL MOISTURE. THE NEXT RISK FOR SHOWERS AND
STORMS WILL ARRIVE BEGINNING MONDAY AFTERNOON.
&&
.MARINE...
ISSUED AT 314 AM EDT SUN JUN 22 2014
SUMMARY: HIGH PRESSURE OVER HUDSON BAY WILL MOVE SOUTH AND EAST OFF
THE ATLANTIC COAST THROUGH MONDAY ALLOWING AN AREA OF LOW PRESSURE
TO MOVE INTO THE GREAT LAKES REGION FOR MONDAY NIGHT AND TUESDAY.
HIGH PRESSURE BUILDS INTO THE REGION BEHIND THIS LOW FOR WEDNESDAY
AND THURSDAY.
HEADLINES: WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT LEVELS
THROUGH MONDAY NIGHT. THERE IS SOME POTENTIAL FOR SMALL CRAFT LEVEL
WINDS UNDER NORTHWEST WINDS TUESDAY/TUESDAY NIGHT AS LOW PRESSURE
DEPARTS THE REGION TO THE EAST. AS LOW PRESSURE PULLS EAST OF THE
REGION HIGH PRESSURE BUILDS IN FOR THE WEDNESDAY-FRIDAY TIMEFRAME
WITH HEADLINE FREE CONDITIONS EXPECTED.
THUNDERSTORMS: CHANCES FOR STORMS INCREASE ON MONDAY WITH A PERIOD
OF THUNDERSTORMS LIKELY TUESDAY/TUESDAY NIGHT. WIDESPREAD SEVERE
THREAT IS LOW...BUT ISOLATED STRONG TO SEVERE STORMS ARE POSSIBLE.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...SMITH
SYNOPSIS...SMD
SHORT TERM...ARNOTT
LONG TERM...SMD
AVIATION...BS
MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
115 PM EDT SUN JUN 22 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 523 AM EDT SUN JUN 22 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER
CNTRL SASK/MANITOBA AND A DOWNSTREAM RIDGE FROM THE NRN LAKES TO
JAMES BAY. AT THE SFC...TROUGH EXTENDED INTO THE ERN DAKOTAS AND
CNTRL NEBRASKA FROM LOW PRES NEAR LAKE WINNIPEG WHILE HIGH PRES
PREVAILED TO THE EAST FROM SRN QUEBEC INTO THE NRN LAKES. A SHRTWV
TROUGH AHEAD OF THE MID LEVEL LOW SUPPORTED SOME SHRA/TSRA FROM NW
ONTARIO TO NEAR KELO. HOWEVER...THE STRONGER AND MORE WIDEPSREAD
CONVECTION WAS WELL TO THE SOUTH FROM ERN NEBRASKA INTO WRN IA WHERE
THE MORE FAVORABLE INSTABIILITY (MUCPAE TO NEAR 2K J/KG) AND
MOISTURE TRANSPORT WAS LOCATED. OTHERWISE...MAINLY LOW STRATUS
PREVAILED ACROSS MUCH OF WEST AND CENTRAL UPPER MI WHERE LOW LEVEL
MOISTURE REMAINS BELOW THE 925 MB INVERSION.
TODAY...EXPECT THAT THE SHRA/TSRA ASSOCIATED WITH THE MODEST FORCING
ASSOCIATED WITH THE NW ONTARIO SHRTWV WILL WEAKEN AS IT MOVES TOWARD
THE RIDGE. DAYTIME HEATING SHOULD BREAK UP THE LOWER CLOUDS SO THAT
AFTERNOON SUNSHINE WILL PUSH TEMPS INTO THE LOWER 80S INLAND WHILE
LAKE BREEZES LIMIT READINGS TO THE 60S NEAR THE GREAT LAKES. THE NAM
AND SEVERAL HIGHER RES MODELS SUGGEST THAT THERE WILL BE ENOUGH
INSTABILITY FOR SOME SHRA/TSRA OVER MAINLY THE WEST THIRD DURING THE
AFTERNOON. HOWEVER...SINCE MORE MODEST MLCAPE VALUES INTO THE
300-600 J/KG RANGE ARE EXPECTED AND LARGE SCALE FORCING IS NOT
FCST...CONFIDENCE FOR SHRA/TSRA DEVELOPMENT IS LOW AND ONLY SLIGHT
CHANCE POPS WERE INCLUDED.
TONIGHT...ANY CONVECTION THAT DEVELOPS DURING THE AFTERNOON WILL
DIMINISH DURING THE EVENING. HOWEVER...AS THE TROUGH AND FRONTAL
BOUNDARY EDGE TOWARD THE WRN CWA OVERNIGHT...SHRA/TSRA CHANCES WILL
INCREASE AS ADDITIONAL WEAK SHORTWAVES EMERGE FROM THE PLAINS. THERE
IS LESS CONFIDENCE IN THE EASTWARD EXTENT OF THE PCPN AS THE RIDGE
TO THE EAST LIMITS THE MOVEMENT OF THE MOISTURE AXIS TO THE EAST. IN
ADDITION...ANOTHER ROUND OF STRONGER CONVECTION IS MORE LIKELY OVER
NRN IA OR SRN MN INTO SRN WI THAT WOULD LIMIT MOISTURE TRANSPORT TO
THE NORTH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 509 AM EDT SUN JUN 22 2014
MONDAY CONTINUES TO LOOK LIKE A SHOWERY DAY ACROSS MUCH OF THE
WESTERN HALF OF UPPER MICHIGAN AS THE UPPER LOW OVER
MANITOBA/SASKATCHEWAN FINALLY OPENS UP AND SLOWLY MOVES EASTWARD.
MEANWHILE...A WEAK UPPER SHORT WAVE OVER THE CENTRAL PLAINS MOVES
TOWARD THE REGION. THESE TWO FEATURES WILL WILL ALLOW FOR WEAK LOW
PRESSURE TO DEVELOP OVER THE MID MS VLY AND MOVE TOWARD THE GREAT
LAKES. MOISTURE AND WARM ADVECTION AHEAD OF THE TROUGH WILL SPREAD
ACROSS THE AREA MONDAY AND BE SLOW TO MOVE OUT UNTIL THE LOW PASSES
BY TUE. EXPECT SHOWERS AND ISOLATED STORMS TO DEVELOP ACROSS THE
WESTERN U.P. MON MORNING THEN SLOWLY SPREAD EASTWARD DURING THE DAY
AS THE 850MB TROUGH AND ASSOCIATED MOISTURE CONVERGENCE MOVES EAST.
WITH THE COMBINATION OF THE FAVORABLE DYNAMICS FROM THE SHORT WAVE
ENERGY AS WELL AS HIGH MOISTURE CONTENT OF THE ATMOSPHERE
/PRECIPITABLE WATER VALUES AROUND 1.75 INCHES/...EXPECT A FEW AREAS
ACROSS THE WEST HALF TO SEE 0.50 TO 1.0 INCHES OF RAIN MONDAY UNDER
THE HEAVIEST AND MOST PERSISTENT SHOWER ACTIVITY. AS SUCH...WILL
KEEP LIKELY POPS ACROSS THE ENTIRE WESTERN HALF OF THE FORECAST AREA
ON MONDAY. FUTURE SHIFTS WILL LIKELY NEED TO RAISE POPS MORE...BUT
THERE IS STILL SOME UNCERTAINTY EXACTLY WHERE THE BEST RAIN WILL SET
UP.
AS THE LOW MOVES SOUTH OF THE AREA MONDAY NIGHT...THE COLD FRONT
ASSOCIATED WITH THE NORTHERN STREAM ENERGY WILL DIVE SOUTHWARD.
MOISTURE WILL PERSIST ACROSS MUCH OF THE EASTERN HALF OF UPPER
MICHIGAN MONDAY NIGHT COMBINED WITH SYNOPTIC FORCING FROM THE UPPER
TROUGH. AS SUCH...WILL MAINTAIN LIKELY POPS EAST FOR MONDAY NIGHT
TAPERING TO CHANCE POPS FOR THE WEST.
TUESDAY MAY END UP BEING A FAIRLY RAW DAY ACROSS AT LEAST THE
NORTHERN HALF OF UPPER MI WITH NORTHERLY FLOW BEHIND THE LOW
COMBINED WITH SCATTERED SHOWERS DUE TO THE CONTINUE 850MB BAROCLINIC
ZONE ACROSS THE AREA AND DEEP MOISTURE. WILL MAINTAIN CHANCE POPS
ACROSS THE ENTIRE AREA ALTHOUGH CLOSER TO LAKE SUPERIOR MAY SEE MORE
DRIZZLE THAN ANYTHING. AREAS CLOSE TO LAKE SUPERIOR MAY STRUGGLE TO
RISE OUT OF THE MID 50S ON TUESDAY ALTHOUGH INLAND AREAS WILL SEE
TEMPS RISE WELL INTO THE 60S.
FOR TUE NIGHT/WED...HIGH PRESSURE BUILDS ACROSS THE AREA LEADING TO
A DRY PERIOD THROUGH WED NIGHT. HIGH PRESSURE HANGS ON THRU THU
ALTHOUGH THE ECMWF AND GFS BOTH SUGGEST ANOTHER SHORT WAVE MOVING
INTO THE UPPER LAKES DURING THE DAY WHICH MAY ALLOW FOR SHOWERS AND
ISOLATED STORMS DURING THE AFTERNOON. UPPER RIDGING FINALLY BUILDS
IN FOR THE WEEKEND WHICH MEANS TEMPERATURES RISING TO ABOVE NORMAL.
MAY BE A CHANCE FOR RAIN FRI NIGHT INTO SATURDAY AS WEAK WARM
ADVECTION DEVELOPS...BUT LATEST ECMWF SUGGESTS THAT THE RAIN CHANCES
WILL HOLD OFF UNTIL SAT NIGHT/SUN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 115 PM EDT SUN JUN 22 2014
MORE FOG AND LOW CLOUDS COULD ROLL IN OFF LAKE SUPERIOR THIS EVENING
AT CMX. A FEW SHOWERS ARE POSSIBLE LATE TONIGHT AT CMX AND IWD BUT
ARE NOT EXPECTED TO REDUCE CONDITIONS BELOW VFR AT IWD AND THE FOG
WILL PRODUCE MVFR CONDITIONS AT CMX. UPSLOPE FOG WILL FORM AT SAW
OFF LAKE MICHIGAN TONIGHT WITH SOUTH TO SOUTHEAST WINDS...THEN AS
WINDS GO TO THE SW LATE...THE FOG WILL DISSIPATE. VFR CONDITIONS
WILL PREVAIL THROUGH THE PERIOD AT SAW AND IWD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SUN JUN 22 2014
DENSE FOG WILL CONTINUE TO BE THE MAIN CONCERN ACROSS WEST AND
CENTRAL LAKE SUPERIOR. LINGERING LOW LEVEL MOISTURE WITH PERSISTENT
LIGHT E OR SE LOW LEVEL FLOW WILL ALLOW FOR DENSE FOG WILL HELP TO
MAINTAIN THE FOG OR LOW STRATUS TODAY. THERE MAY BE ENOUGH DRY AIR
MOVING IN THIS AFTERNOON TO MIX OUT THE FOG BUT THERE IS THE
POSSIBILITY THAT AN EXTENSION OF THE DENSE FOG ADVISORY MAY BE
NEEDED. WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH THIS
FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>248-263>265.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...MRD
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
102 PM CDT Sun Jun 22 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 336 AM CDT Sun Jun 22 2014
Once again the main forecast issue is thunderstorm chances. The
only ongoing precipitation early this morning is a shrinking area
of showers in Pike Co MO. This originated from a NW-SE cluster of
thunderstorms which occurred just north of Mexico in response to
lift via a weak westerly LLJ along the cool side of a large scale
outflow boundary. That boundary remains somewhat identifiable
from far southern IL into central/NW MO. While there is no clear
cut model solution, there are suggestions by the deterministic
guidance which are supported by recent runs of the HRRR and the
4km NSSL WRF that this confluent zone from central through
southeast MO will be the region of scattered thunderstorm
development beginning near midday, with activity shifting east thru
the afternoon. There may be a region of somewhat greater coverage
and organization across northeast Missouri and west central IL
resulting from an eastward migrating vort max which is now present
in the central Plains. Highs once again look seasonable in the
upper 80s to lower 90s.
Glass
.LONG TERM: (Tonight through Saturday)
Issued at 336 AM CDT Sun Jun 22 2014
The greatest threat of thunderstorms tonight should also reside
across the northern portion of the CWA where the consensus of the
model QPFs have the highest coverage. This appears reasonable as a cold
front will be pushing into IA and NW MO in association with a much
better defined slowly progressive short wave trof and attendant
vort maxes. Strengthening and veering wind fields and a stronger
veering WSW LLJ should result in good eastward progression of
organized convection. The cold front will move slowly across the
area Monday and Monday night and should be accompanied by fairly
widespread showers and thunderstorms. The models vary on how far
south the front will push on Tuesday with the NAM showing the
least progression only into southern IL and southern MO while the
GFS and SREF push the front into AR. Eventually the front will
retreat back northward and be the focus for additional showers and
thunderstorms through the later half of the upcoming week. The NAM
is just about 12-24h faster thru its 84h forecast ending Wednesday.
Glass
&&
.AVIATION: (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1249 PM CDT Sun Jun 22 2014
Scattered thunderstorms are the primary concern this afternoon.
Greater coverage should be across the eastern Ozarks and northeast
Missouri/west central Illinois this afternoon. Unfortunately,
there`s little forcing in the atmosphere today to latch on to and
try to figure timing at any given TAF site. This will definitely be
a reactionary afternoon of updating forecasts as thunderstorm
cells pop up. VFR flight conditions will prevail outside of
storms. Storms should diminish after sunset.
A weak trof of low pressure will move into the area on Monday.
Expect more widespread showers and thunderstorms to develop and
overspread the area from late morning into Monday afternoon.
Specifics for KSTL:
Scattered thunderstorms are the primary concern this afternoon.
Unfortunately, there`s little forcing in the atmosphere today to
latch on to and try to figure timing at Lambert. This will
definitely be a reactionary afternoon of updating forecasts as
thunderstorm cells pop up. VFR flight conditions will prevail
outside of storms. Storms should diminish after sunset.
A weak trof of low pressure will move into the area on Monday.
Expect more widespread showers and thunderstorms to develop and
overspread the area from late morning into Monday afternoon.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
341 PM CDT SUN JUN 22 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 341 PM CDT SUN JUN 22 2014
AT 19Z...WATER VAPOR SHOWED QUASI-ZONAL FLOW ACROSS MUCH OF THE
CONUS WITH AN UPPER LEVEL LOW SPINNING OVER THE CENTRAL
SASKATCHEWAN/MANITOBA BORDER. MULTIPLE WEAK SHORTWAVES COULD BE
PICKED OUT MOVING ACROSS THE ROCKIES...FROM MONTANA DOWN THROUGH NEW
MEXICO. THE STRONGER SHORTWAVE WAS SEEN OVER WESTERN COLORADO AT MID
AFTERNOON WHICH WILL IMPACT THE FORECAST FOR TONIGHT...WITH THE
SECOND MORE DISTINCT SHORTWAVE SEEN OVER EASTERN IDAHO...WHICH WILL
IMPACT THE FORECAST FOR MONDAY. AT THE SURFACE...A COLD FRONT WAS
SITUATED FROM SOUTHWEST KANSAS INTO NORTHWEST MISSOURI. NORTH OF
THIS FRONT COLD AIR HAD ADVECTED INTO NEBRASKA...WITH MID AFTERNOON
TEMPERATURES GENERALLY IN THE 70S AND LOW 80S. DECENT LOW LEVEL
MOISTURE DID REMAIN IN PLACE...AS DEWPOINTS ACROSS THE AREA WERE
STILL IN THE UPPER 50S AND 60S. WITH THE MOISTURE IN PLACE AND STEEP
LOW LEVEL LAPSE RATES...AN EXTENSIVE CUMULUS FIELD HAD DEVELOPED
ACROSS WESTERN NEBRASKA. DESPITE DECENT SB INSTABILITY OF 1500-2500
J/KG WITH NO CAP...ANY SHOWERS AND THUNDERSTORMS HAVE HAD A PROBLEM
MAINTAINING WITH NO ADDITIONAL FORCING IN PLACE.
FOR THIS EVENING AND TONIGHT...ALTHOUGH THE HRRR IS INDICATING
STORMS DEVELOPING OVER SOUTHWEST NEBRASKA AHEAD OF THE MAIN SYSTEM
OVER THE ROCKIES...FEEL THIS ACTIVITY WILL BE WEAK WITH THE LACK OF
FORCING FROM THE SHORTWAVE AND VERY LITTLE IF ANY FORCING COMING
FROM ANY LOW LEVEL MOISTURE TRANSPORT. SO WILL FOCUS ON ACTIVITY
MOVING OUT ONTO THE PLAINS WITH THE MAIN SHORTWAVE. AS THIS SHORTWAVE
OVER WESTERN COLORADO MOVES EAST EXPECT FURTHER DEVELOPMENT OF
CONVECTION ALONG THE FOOTHILLS AND INTO THE HIGH PLAINS. THE
QUESTION WILL BE HOW FAR NORTH THE CONVECTION WILL DEVELOP. THE
LATEST FEW RUNS OF THE HRRR INDICATE ACTIVITY DEVELOPING AS FAR
NORTH AS SCOTTSBLUFF. THESE STORMS WOULD THEN MOVE SOUTHEAST ALONG A
THETA-E GRADIENT. ALTHOUGH THERE IS SUFFICIENT INSTABILITY AND DEEP
LAYER SHEAR WILL BE INCREASING...THE LOCAL AREA WILL BE ON THE
NORTHERN FRINGE OF ANY ACTIVITY AND WITH THE BETTER FORCING OVER
KANSAS EXPECT THE THREAT FOR ANY SEVERE STORMS TO STAY SOUTH OF THE
AREA.
FOR MONDAY THE SHORTWAVE TROUGH NOW OVER EASTERN IDAHO WILL MOVE
ACROSS WYOMING AND THEN ACROSS NEBRASKA FROM NORTHWEST TO SOUTHEAST.
NOT EXTREMELY CONFIDENT ON HOW MUCH COVERAGE OF SHOWERS AND
THUNDERSTORMS THERE WILL BE AS THE AIRMASS WILL BE SLIGHTLY
DRIER...WITH DEWPOINTS MAINLY IN THE 50S AND NO REAL SURGE OF DEEP
MOISTURE ALOFT. AT THE PRESENT TIME THINK ANY CONVECTION WILL BE
MORE ISOLATED TO SCATTERED IN NATURE. THE NEXT QUESTION IS WHERE THE
CONVECTION WILL ACTUALLY BE. THE NAM SHOWS QPF ACROSS MUCH OF THE
FORECAST AREA WHILE THE GFS/ECMWF ARE KEEPING IT MAINLY OVER THE
PANHANDLE AND SOUTHWEST NEBRASKA. HAVE SIDED WITH THE GFS/ECMWF FOR
TODAY AND HAVE LIMITED CHANCES FOR THE WESTERN AREAS. AS FOR HIGHS
ON MONDAY...LOOKING FOR A SLIGHTLY COOLER DAY WITH HIGHS IN THE 70S
AND LOW 80S AS COOLER AIR SLOWLY CONTINUES TO FILTER INTO THE AREA
BEHIND THE UPPER LEVEL SYSTEM OVER SOUTHERN CANADA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 341 PM CDT SUN JUN 22 2014
NORTHWEST FLOW ALOFT WILL PERSIST MONDAY NIGHT THROUGH TUESDAY
NIGHT WITH THE PASSAGE OF TWO DISTINCT DISTURBANCES. MAINTAINED 30
POPS LATE MONDAY NIGHT ACROSS WESTERN ZONES...TO 40 POPS
TUESDAY/TUESDAY NIGHT. PWAT VALUES FROM GFS INDICATE 120 TO NEAR 140
PERCENT OF NORMAL WITH DEEP LAYER SHEAR INCREASING TO 30 TO 40
KTS. THIS SUPPORTIVE OF STRONG THUNDERSTORMS TUESDAY AFTN/EVENING
WITH LOCALLY HEAVY RAINFALL DUE TO SLOW STORM MOTION NEAR 10 KTS.
SECOND DISTURBANCE FORECAST TO LIFT ACROSS LATE TUESDAY NIGHT AND
WEDNESDAY WITH 40 POPS TUESDAY NIGHT...FOLLOWED BY 40 POPS FOR
NCTRL WEDNESDAY.
MAINLY 20 TO 30 POPS THURSDAY THROUGH SATURDAY. DUE TO WEAK RIDGING
OVER THE REGION AND SWRLY FLOW TO OUR WEST WHICH MOVES IN BY
FRIDAY NIGHT...MODEL AGREEMENT IN TIMING AND LOCATION IS RATHER
POOR. TEMPERATURES HOWEVER WILL WARM FROM THE UPPER 70S TO LOWER
80S TUESDAY...MID 80S THURSDAY THROUGH SATURDAY TO AROUND 90 BY
SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1246 PM CDT SUN JUN 22 2014
PLENTIFUL CLOUD COVER IS EXPECTED ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA THROUGH MONDAY AFTERNOON AS MULTIPLE WEAK SYSTEMS
CROSS THE ROCKIES TO BRING MOISTURE INTO THE REGION. CEILINGS ARE
EXPECTED TO STAY VFR THROUGH THIS FORECAST PERIOD THOUGH. THERE IS
A CHANCE FOR THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS MUCH
OF THE AREA...HOWEVER COVERAGE IS EXPECTED TO BE ISOLATED TO
SCATTERED. HAVE THE MENTION OF VCTS AT KLBF AS THE HIGHER
PROBABILITIES FOR STORMS LATER THIS AFTERNOON AND EVENING WILL BE
ACROSS SOUTHWEST NEBRASKA. CONFIDENCE ON ANY MOVING ACROSS THE
KVTN TERMINAL IS LOW SO HAVE NOT INCLUDED THUNDER MENTION IN THE
FORECAST AT THAT LOCATION. ANOTHER SYSTEM DOES LOOK TO CROSS
NEBRASKA ON MONDAY...BUT TIMING INTO THE TAF SITES WOULD LIKELY BE
LATE IN THE PERIOD OR POSSIBLY AFTER 18Z...IF ACTIVITY DOES IN
FACT DEVELOP. LOW CONFIDENCE IN THIS SCENARIO CURRENTLY SO A QUIET
FORECAST IS ONGOING CURRENTLY FOR MONDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BROOKS
LONG TERM...ROBERG
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
309 PM CDT SUN JUN 22 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 301 PM CDT SUN JUN 22 2014
THE PRIMARY SHORT TERM FORECAST CONCERN CENTERS AROUND THE CHANCE OF
THUNDERSTORMS THIS AFTERNOON INTO TONIGHT. OVER THE LAST 8 HOURS
HAVE GREATLY REDUCED THUNDERSTORM CHANCES FOR THIS AFTERNOON AND
TONIGHT ACROSS OUR FORECAST AREA. THE GREATEST REDUCTION IN
THUNDERSTORM CHANCES HAS BEEN ACROSS NEBRASKA.
THERE IS MODEST TO EVEN FAIRLY GOOD INSTABILITY ACROSS THE FORECAST
AREA ESPECIALLY ACROSS KANSAS...WITH LITTLE TO NO CIN. WIND SHEAR IS
RATHER WEAK WITH DEEP LAYER 0-6 KM SHEAR OF LESS THAN 30 KTS. THE
BIG ISSUE CENTERS AROUND FORCING OR THE LIFTING MECHANISM FOR
ORGANIZED CONVECTION. FORCING MECHANISMS ACROSS THE REGION INCLUDE
AN UPPER LEVEL SHORT WAVE TROUGH OVER IOWA...A SOUTHWARD SLIPPING
SFC FRONTAL BOUNDARY ACROSS NORTHERN KANSAS...AND A VERY WEAK UPPER
WAVE CENTERED OVER THE BLACK HILLS OF SOUTH DAKOTA EXTENDING INTO
THE NEBRASKA PANHANDLE. THE SFC FRONT IS THE PRIMARY FORCING
MECHANISM CURRENTLY LOCATED OVER OUR FORECAST AREA AND IT IS
GRADUALLY SINKING SOUTH WHERE IT WILL EXIT OUR AREA BY LATER THIS
EVENING. THEREFORE...THUNDERSTORMS SEEM MOST LIKELY LATE THIS
AFTERNOON INTO EARLY THIS EVENING IN CLOSE PROXIMITY TO THE SFC
FRONT OVER NORTHERN KANSAS AND THUS HAVE KEPT POPS AROUND 50/50 IN
THESE SOUTHERN ZONES...WITH THE HIGHER POPS REALLY BEING SOUTH OF
OUR FORECAST AREA TONIGHT. SOME FORECAST MODELS GENERATE CONVECTION
ACROSS THE HIGH PLAINS TONIGHT IN ASSOCIATION WITH THE VERY WEAK
UPPER WAVE...BUT 4 OUT OF 6 MODELS HAVE THIS PRECIPITATION DIEING
OFF BEFORE REALLY REACHING OUR AREA TONIGHT. ONE OUTSIDE WRF RUN AND
THE HRRR DO BRING CONVECTION FROM WESTERN PORTIONS OF NEBRASKA AND
KANSAS INTO OUR FORECAST AREA LATE TONIGHT WHILE MOST MODELS DO NOT.
WILL GO WITH THE MAJORITY GIVEN THERE IS NOT MUCH OF A LOW LEVEL JET
TO HELP SUSTAIN CONVECTION TONIGHT ACROSS OUR FORECAST AREA. ANY
THUNDERSTORMS THAT CAN FORM THIS AFTERNOON OR EVENING ACROSS KANSAS
COULD BECOME SEVERE GIVEN THE HIGHER INSTABILITY ACROSS OUR SOUTHERN
ZONES.
MONDAY...MOST FORECAST MODELS INDICATE THAT WE WILL BE IN BETWEEN
WEAK SHORT WAVE STORM SYSTEMS AND LIKELY DRY. TEMPERATURES WILL BE
MILD WITH A LIGHT NORTHEAST WIND KEEPING THINGS A BIT COOLER THAN
TODAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 301 PM CDT SUN JUN 22 2014
THE WEATHER PATTERN REMAINS UNSETTLED DURING THE EXTENDED PERIODS
WITH INTERMITTENT CHANCES FOR THUNDERSTORMS. AN UPPER LOW PRESSURE
SYSTEM WILL BE TRANSLATING SOUTHEAST FM CANADA TO THE UPPER MIDWEST
REGION AT THE ONSET OF THE EXTENDED WITH THE FLOW ALOFT
TRANSITIONING WEST NORTHWEST FOR A TIME AS ANOTHER TROUGH DIGS INTO
THE PACIFIC NORTHWEST REGION. A SERIES OF WAVES EMBEDDED IN THE
FLOW WILL AID IN TSTM DEVELOPMENT WITH TIMING/PLACEMENT DEPENDENT
UPON WAVE TIMING AND BOUNDARY LOCATIONS AND BOUNDARY LOCATION WILL
BE DEPENDENT UPON HOW CONVECTION UNFOLDS THE PREVIOUS DAY. IT IS
DIFFICULT TO PINPOINT DETAILS ATTM AND WITH THE PROGRESSIVE PATTERN
JUST CANNOT RULE OUT TSTM CHCS NEARLY EVERY DAY. CONVECTION MAY
DEVELOP ALONG THE HIGH PLAINS AND ROLL EASTWARD...OR MAY INITIATE
ALONG A BOUNDARY WITHIN THE AREA.
SREF INSTABILITY PROGS INDICATE THE GREATER INSTABILITY MONDAY NIGHT
WILL RESIDE ALONG THE HIGH PLAINS REGION...WHICH WILL BEGIN TO
SPREAD EASTWARD ON TUESDAY...WITH MUCAPES INCREASING TO NEAR OR JUST
ABOVE 1000 J/KG. WITH THE MORE MARGINAL INSTABILITY ON
TUESDAY...NOT LOOKING FOR MUCH SEVERE WX JUST YET WITH INSTABILITY
FURTHER INCREASING TUESDAY NIGHT INTO MID WEEK WITH RETURN
FLOW...STRENGTHENING NOCTURNAL LLVL JET AND WAA/UPPER RIDGING AHEAD
OF UPPER TROUGH IN THE PACIFIC NW. UPPER RIDGING SETTLES OVERHEAD
FOR THE LATTER PART OF THE WORKWEEK AND MID LEVEL TEMPS INCREASE TO
AROUND 14C SO CAP MAY LIMIT CONVECTION FOR A TIME. MODELS ARE NOT
IN GREAT AGREEMENT ON THE TIMING/PROGRESSION OF THE WESTERN TROUGH
AS IT PUSHES EAST THRU THE MOUNTAINS TOWARDS THE PLAINS AND WILL NEED TO
MONITOR BUT CHCS FOR STORMS INCREASE AGAIN WITH THIS SYSTEM OVER THE
WEEKEND OR EARLY NEXT WEEK. ALL BEING SAID...INTERMITTENT CHANCES
FOR STORMS CONTINUE AND TEMPS LOOK FAIRLY SEASONAL ATTM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 104 PM CDT SUN JUN 22 2014
REDUCED THUNDERSTORM CHANCES EVEN FURTHER WITH LATEST UPDATE BASED
ON LATEST FORECAST MODEL RUNS. THE CHANCE OF THUNDERSTORMS AT KGRI
IS NOW AROUND 30 PERCENT AT ITS HIGHEST POINT AND THIS MAY BE ON
THE HIGH SIDE. THEREFORE...HAVE ELECTED TO REMOVE MENTION OF
VICINITY THUNDERSTORMS FROM THE TAF. THE WIND WILL BE LIGHT AND
GENERALLY OUT OF THE NORTH BEHIND THE FRONT TODAY AND
TOMORROW...ALTHOUGH IT COULD BE A BIT VARIABLE TONIGHT. VFR SKY
AND VISIBILITY CONDITIONS ARE EXPECTED.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...WESELY
LONG TERM...FAY
AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1247 PM CDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 1048 AM CDT SUN JUN 22 2014
THE FORECAST WAS UPDATED FOR PRECIPITATION AND WEATHER FOR TODAY.
PARTLY TO MOSTLY SUNNY SKIES ARE CURRENTLY BEING OBSERVED. THE
RAIN OVER THE NORTHEAST PART OF THE FORECAST AREA HAS MOVED EAST
OF THE AREA. WITH THE EXCEPTION OF A FEW WEAK RADAR ECHOES THAT
HAVE MOVED ACROSS NORTHERN SHERIDAN COUNTY...THE SHOWERS AND
ISOLATED THUNDERSTORMS OVER SOUTH DAKOTA HAVE STAYED NORTH OF THE
FORECAST AREA. THE HRRR HAS BEEN HANDLING THIS ACTIVITY FAIRLY
WELL...HAVING IT MOVE STRAIGHT EAST RATHER THAN DIPPING SOUTH AS
HAD BEEN PREVIOUSLY FORECAST. DUE TO THESE TRENDS...CHANCES HAVE
BEEN REMOVED FOR MOST PLACES THROUGH THE MORNING HOURS. THERE IS
SOME INSTABILITY ACROSS THE AREA...IN THE ORDER OF 500-1500 J/KG
SB CAPE ACCORDING TO THE SPC MESOANALYST PAGE AT 1530Z. THIS
SHOULD STAY FAIRLY STABLE THROUGH THE AFTERNOON. THERE WILL BE A
LACK OF FORCING THOUGH THIS AFTERNOON AS SHORTWAVES ARE LOOKING TO
MOVE ACROSS SOUTH DAKOTA...AND THEN OUT OF COLORADO AND INTO
KANSAS LATER IN THE DAY. FEEL THAT THERE MAY BE SOME ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS...BUT WITH THE LACK OF FORCING
ACTIVITY SHOULDN/T BE WIDESPREAD SO HAVE LOWERED THE COVERAGE OF
STORMS IN THE FORECAST FOR THIS AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT SUN JUN 22 2014
OUTFLOW DOMINANT TSTMS CONTINUE TO DEVELOP PRODUCING LOCALLY HEAVY
RAINFALL THIS MORNING. STORM DEVELOPMENT IS BEING AIDED BY MODEST
MOISTURE ADVECTION AS SHOWN BY THE RAP MODEL AND NOCTURNAL COOLING
IN THE MID LEVELS OF THE ATMOSPHERE. THE RAP SHOWS THIS MOISTURE
TRANSPORT SHIFTING OFF EAST OF THE FCST AREA TOWARD 12Z WITH THE
HEAVY RAIN BECOMING LIGHT TO MODERATE. THE ATMOSPHERE IS EXPECTED TO
BECOME UNSTABLE THIS AFTERNOON WITH CONVECTION REDEVELOPING BUT NOT
NEARLY AS UNSTABLE AS IT IS NOW. SCATTERED POPS ARE IN PLACE FOR THE
AFTERNOON HOURS WHICH BECOME ISOLATED TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 345 AM CDT SUN JUN 22 2014
MONDAY AND BEYOND. ACTIVE PATTERN TO CONTINUE THROUGH MUCH OF THE
EXTENDED AS PLENTIFUL GULF MOISTURE WORKS WITH A NORTHWARD
RETREATING FRONTAL BOUNDARY AND PERIODIC WEAK IMPULSES PASSING
THROUGH THE WESTERLIES IN QUASI ZONAL FLOW...THUS...NEAR
DAILY/NIGHTLY THUNDERSTORMS CHANCES TO REMAIN IN THE EXTENDED
FORECAST. LOOKING TO LATE WEEK...THE SYNOPTIC SCALE FLOW ACROSS
THE CENTRAL/NORTHERN PLAINS APPEARS TO UNDERGO A TRANSITION AS
THERE REMAINS STRONG AGREEMENT OF THE DEVELOPMENT OF A SIGNIFICANT
UPPER TROUGH OVER THE WESTERN CONUS. LOW AMPLITUDE TRANSITORY
RIDGING THURSDAY MAY PROVIDE FOR A BRIEF DRY PERIOD...BUT
PRECIPITATION CHANCES RAMP BACK UP WITH THE APPROACH OF WEAK
SHORTWAVES FROM THE WESTERN CONUS TROUGH LATE WEEK AND NEXT
WEEKEND.
FOR THE DAILY DETAILS...DRIER AIR TO WORK ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA ON MONDAY...WITH PLEASANT CONDITIONS ANTICIPATED
FOR MOST IF NOT ALL OF THE CWA. THE EXCEPTION BEING WHERE WEAK
UPSLOPE FLOW AND THE PASSAGE OF THE NEXT SUBTLE WAVE MAY PROVIDE FOR
A FEW STORMS MONDAY EVENING AND THROUGH THE OVERNIGHT ACROSS THE
HIGHER TERRAIN OF WESTERN NEBRASKA. WILL MAINTAIN SLIGHT CHANCE POPS
IN THIS AREA...BUT EXPECT MOST OF THE ACTIVITY TO BE TIED TO THE
HIGHER TERRAIN WEST OF THE CWA. A MORE NOTABLE WAVE ARRIVES ON
TUESDAY WHEN THE AFOREMENTIONED FRONT LIFTS NORTH ACROSS THE AREA.
WITH RETURN SOUTHERLY FLOW IN PLACE...MOISTURE WILL BE AVAILABLE FOR
STORMS...POSSIBLY WIDESPREAD WITH HEAVY RAINFALL. THIS ACTIVITY
WILL SPREAD EAST THROUGH THE DAY...WITH ADDITIONAL STORMS POSSIBLE
OVERNIGHT WITH THE DEVELOPMENT OF A WEAK TO MODERATE HIGH PLAINS
LLJ. TIMING AND LOCATION OF THE PROJECTED CONVECTION AND/OR
COMPLEXES IS NOT READILY APPARENT ATTM...SO WILL GENERALLY
BROADBRUSH 30-40% POPS MOVING WEST TO EAST ACROSS THE ENTIRE CWA
TUESDAY THROUGH EARLY WEDNESDAY MORNING. ADDITIONAL STORMS WILL BE
POSSIBLE WEDNESDAY AS THE ATMOSPHERE REMAINS UNSTABLE WITH A FRONT
IN THE REGION AND ANOTHER SUBTLE WAVE PASSAGE. LIKEWISE...WIDESPREAD
30-40% POPS WEDNESDAY INTO EARLY THURSDAY ARE WARRANTED. FOR LATE
THURSDAY THROUGH THE UPCOMING WEEKEND...MOST OF THE UPPER ENERGY IS
SHOWN TO BE DIRECTED TO THE WEST AND NORTH OF THE CWA...BUT THERE
STILL REMAINS STRONG SUPPORT OF WAVE IMPACTING THE CWA FRIDAY
NIGHT INTO SATURDAY. THE CR ALLBLEND INT GENERATED CHANCE POPS FOR
MUCH OF THE CWA...GIVEN THIS SUPPORT...SEE NO REASON TO DEVIATE
FROM THE PROCEDURE ATTM.
TEMPERATURES THROUGH THE EXTEND PERIODS WILL UNDERGO A SLIGHT
WARMING TREND WITH HIGHS GENERALLY IN THE UPPER 70S TO LOWER 80S ON
MONDAY...BUT RISE INTO THE MID TO UPPER 80S BY FRIDAY. A FEW LOWER
90S MAY BE POSSIBLE SOUTH OF THE INTERSTATE LATE WEEK AS
DEVELOPING SURFACE LOW DIRECTS AN AIRMASS FROM THE DESERT SW INTO
WESTERN NEBRASKA. LOWS TO REMAIN SEASONAL THROUGH THE EXTENDED
FORECAST PERIODS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1246 PM CDT SUN JUN 22 2014
PLENTIFUL CLOUD COVER IS EXPECTED ACROSS WESTERN AND NORTH
CENTRAL NEBRASKA THROUGH MONDAY AFTERNOON AS MULTIPLE WEAK SYSTEMS
CROSS THE ROCKIES TO BRING MOISTURE INTO THE REGION. CEILINGS ARE
EXPECTED TO STAY VFR THROUGH THIS FORECAST PERIOD THOUGH. THERE IS
A CHANCE FOR THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS MUCH
OF THE AREA...HOWEVER COVERAGE IS EXPECTED TO BE ISOLATED TO
SCATTERED. HAVE THE MENTION OF VCTS AT KLBF AS THE HIGHER
PROBABILITIES FOR STORMS LATER THIS AFTERNOON AND EVENING WILL BE
ACROSS SOUTHWEST NEBRASKA. CONFIDENCE ON ANY MOVING ACROSS THE
KVTN TERMINAL IS LOW SO HAVE NOT INCLUDED THUNDER MENTION IN THE
FORECAST AT THAT LOCATION. ANOTHER SYSTEM DOES LOOK TO CROSS
NEBRASKA ON MONDAY...BUT TIMING INTO THE TAF SITES WOULD LIKELY BE
LATE IN THE PERIOD OR POSSIBLY AFTER 18Z...IF ACTIVITY DOES IN
FACT DEVELOP. LOW CONFIDENCE IN THIS SCENARIO CURRENTLY SO A QUIET
FORECAST IS ONGOING CURRENTLY FOR MONDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BROOKS
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1217 PM CDT SUN JUN 22 2014
.UPDATE...
ISSUED AT 1214 PM CDT SUN JUN 22 2014
SEVERAL MINOR CHANGES WERE MADE TO TODAY MAINLY TO LOWER MAX
TEMPS A BIT NERN ZONES WHERE RESIDUAL CLOUDS WHERE DECREASED
COVERAGE OF MORNING PRECIP WILL LIKELY HAVE LARGEST IMPACT. STRONG
THUNDERSTORMS FAR SERN NEBR WILL BE EXITING SHORTLY AND AMOUNT OF
ATMOSPHERIC RECOVERY REMAINS QUESTIONABLE ON BACK SIDE OF MCV.
HOWEVER...SOME POPS STILL WARRANTED AS SOME HEATING/RECOVERY WILL
OCCUR.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 234 AM CDT SUN JUN 22 2014
MOSAIC RADAR IMAGERY THIS MORNING SHOWING TWO DISTINCT CLUSTER OF
TSTMS...ONE OVER ERN SD ASSOCIATED WITH A SEWD BOUND COLD FRONT/MID
LYR UPGLIDE. OTHER ONE WAS SITUATED ALONG INVERTED SFC TROF/THERMAL
BNDRY EXTENDING FROM NW KS INTO S-CNTRL NEB WITHIN AREA OF MID LYR
QG FORCING. THE LATEST HRRR IS ADVERTISING THE NRN ACTIVITY WILL
QUICKLY DIMINISH THE NEXT COUPLE HOURS WHILE SW TSTMS BECOME
DOMINATE FEATURE AND EXPAND INTO THE CWA EARLY THIS MORNING. FOR
TODAY/TONIGHT...EXPECT COMBINATION OF DAYTIME HEATING AND MOISTURE RICH
ENVIRONMENT EXPECT WILL ALLOW FOR QUICK DESTABILIZATION AND TSTM
REDEVELOPMENT ALONG AXIS OF BNDRY LYR THETA-E CONVG WITH APPROACH
OF FRONTAL BNDRY FROM THE NORTH. AS FOR SEVERE TSTM
POTENTIAL...BOTH NAM AND GFS ARE IN PRETTY GOOD AGREEMENT SHOWING
HIGH BUOYANCY BUT RELATIVELY WEAK VERTICAL WIND SHEAR THUS
FAVORING MULTISTORM DEVELOPMENT. NEVERTHELESS...CANNOT TOTALLY
DISCOUNT A FEW SEVERE STORMS LATE AFTN/EARLY EVENING. PCPN
ACTIVITY WILL BE COMING TO AN END THEN MONDAY MORNING AS DRY
AIRMASS/SUBSIDENCE BUILDS IN FROM THE NORTH. TUES/TUES
NIGHT...MODELS LAY QPF WEST OF THE CWA WITHIN AREA OF PRONOUNCED
MID LYR AGEOSTROPHIC LIFT. PCPN ACTIVITY THEN PROGGED TO EXPAND
QUICKLY EWD INTO THE CWA...THUS WILL LEAVE GOING POPS IN PLACE.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 234 AM CDT SUN JUN 22 2014
GOING FCST HAS PCPN CHANCES PRETTY MUCH IN PLACE THRU THE EXTENDED
PDS. AT THIS POINT GIVEN LATEST MODELS SUPPORT GOING POPS...SEE
LITTLE REASON FOR MAKING ANY MAJOR MODIFICATIONS. ZONAL FLOW EARLY
ON IN THE FCST PD BECOMES MORE AMPLIFIED IN RESPONSE TO A DEEP
UPSTREAM UPPER TROF MOVING ONTO THE WEST COAST THURSDAY BEFORE LARGE
SCALE BEGINS SMOOTHING OUT TO NEAR ZONAL NEXT WEEKEND. PCPN CHANCE
PRETTY MUCH REVOLVING AROUND LIFTING WARM FRONT FOLLOWED BY A COLD
FRONT ADVANCING THRU THE CNTRL PLAINS. THERMAL ADVECTION WITH THESE
BOUNDARIES LOOKS RELATIVELY WEAK SO NOT MUCH DEVIATION FROM NEAR
NORMAL TEMPS ANTICIPATED.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1214 PM CDT SUN JUN 22 2014
ALTHOUGH MORNING CONVECTION HAD SHIFTED SE OF TAF SITES AS OF
17Z...REDEVELOPMENT REMAINS POSSIBLE THROUGH EARLY EVENING AS WEAK
BOUNDARY SAGS SE THROUGH AREA. HOWEVER...TIMING AND COVERAGE WAS
VERY UNCERTAIN AND THUS NO MENTION WAS MADE IN 18Z TAFS. TRENDS
WILL BE MONITORED FOR QUICK UPDATES IF CONDITIONS WARRANT.
OTHERWISE WITH RESIDUAL MOISTURE AROUND...HEATING INTO EARLY AFTN
COMBINED WITH WEAK OUTFLOW FROM MORNING CONVECTION COULD ALLOW FOR
OCCASIONAL MVFR CIGS TO PREVAIL AT SITES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...CHERMOK
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...CHERMOK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
321 PM EDT SUN JUN 22 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL CONTINUE TO EXTEND SOUTH INTO THE
CAROLINAS OVER THE NEXT COUPLE OF DAYS...THOUGH A RISK OF SHOWERS
AND THUNDERSTORMS WILL PERSIST THROUGH MID WEEK. BERMUDA HIGH
PRESSURE BUILDS BACK IN BY MID WEEK AND WILL CONTINUE TO MAINTAIN
ITS INFLUENCE ACROSS THE AREA INTO NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SUNDAY...BEST INSTABILITY THRU EARLY THIS EVENING TO
RESIDE ACROSS THE ILM SC CWA...MAINLY ALONG AND SOUTH OF HIWAY 378.
THE HIGHER POPS OR THE BETTER CHANCE FOR CONVECTION...WILL ALSO BE
EXHIBITED HERE. WITH MID-LEVEL DRYING OVERSPREADING THE FA IN THE
WAKE OF THE FRONT ESPECIALLY ACROSS THE ILM NC COUNTIES...CONVECTION
WILL HAVE A MORE DIFFICULT TIME TO DEVELOP/OCCUR AND THUS A LOWER
AFTN/EVNG POP...COMPARED TO ELSEWHERE ACROSS THE FA...WILL BE
ILLUSTRATED.
MID-LEVEL S/W RIDGING TO AFFECT THE FA...WITH THE UPPER RIDGE AXIS
APPROACHING THE FA FROM THE WEST BY DAYBREAK MON. MODELS INDICATE
THE ATM TO FURTHER DRY ACROSS THE FA AND THUS WILL BACK OFF WITH THE
CLOUDINESS OVERNIGHT. COULD OBSERVE SOME OVERALL CLEAR SKIES
OVERNIGHT ESPECIALLY ACROSS THE ILM NC COUNTIES. VARIOUS MODEL TIME
HEIGHT DISPLAYS INDICATE THIS ATM DRYING TREND.
MODELS ALSO INDICATE A TEMPORARY TIGHTENING OF THE SFC PG AS HIGH
PRESSURE BUILDS ACROSS THE BI-STATE REGION IN THE WAKE OF THE COLD
FRONT...IN TURN KEEPING A NE-E SFC WIND ACTIVE OVERNIGHT ESPECIALLY
AT THE IMMEDIATE COAST. AS FOR TONITES LOWS...HAVE GONE BELOW THE
CONSENSUS OF THE VARIOUS MODEL MOS GUIDANCE...WITH MID TO UPPER 60S
INLAND...TO AROUND 70 OR LOWER 70S AT THE COAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...WITH A WEAK FRONT STALLED SOUTH OF THE
AREA...HIGH PRESSURE WILL CONTINUE TO REIGN OVER THE AREA MONDAY
MORNING...BEFORE RETREATING BACK TO THE NORTH AS THE SYSTEM
PROPAGATES EASTWARD OFF THE NEW ENGLAND COAST LATER IN THE DAY. WITH
A SHIFT IN THE PATTERN...SFC WINDS WILL BECOME EASTERLY...AND THEN
VEER MORE TO THE EAST-SOUTHEAST INTO MONDAY EVENING. COULD SEE SOME
ISOLATED CONVECTION ESPECIALLY IN THE WESTERN SC COUNTIES WITH
DAYTIME HEATING GIVEN HIGHER AMOUNTS OF AVAILABLE MOISTURE WITH PWAT
VALUES NEAR 1.8 INCHES. AS YOU MOVE EASTWARD TO PWAT VALUES DECREASE TO
1.4/1.5 WHICH CONTINUES TO RUN WELL BELOW CLIMATOLOGY FOR THIS TIME
OF YEAR PER LATEST TIME-HEIGHT ANALYSIS AND FCST SOUNDINGS...THUS
HAVE KEPT TREND IN LATEST SET OF POPS FOR THIS WITH HIGHEST IN THE
WESTERN ZONES.
LATEST GUIDANCE LOOKS TO DEPICT A REVERSE TRACK TO THE NORTH OF THE
STALLED FRONT TO OUR SOUTH...AND MOISTURE RETURNS TO THE ENTIRE
FORECAST AREA WITH PWAT VALUES OF 1.6-2.0 INCHES. THOUGH THE ANTICIPATED
FRONT/REMNANTS COULD OFFER SOME LIFT ON TUESDAY...WILL ALSO NEED TO
FOCUS ON AFTERNOON SEA BREEZE AND PIEDMONT TROUGH FOR CONVECTION
DEVELOPMENT. MODELS DO NOTE SOME WEAK MID-LEVEL CAPPING WHICH COULD
INHIBIT DEVELOPMENT...BUT IT IS SHORT-LIVED AND SHOULD NOT INTERFERE
WITH DEVELOPMENT BY TUESDAY AFTERNOON. THUS HAVE SLIGHTLY INCREASED
POPS...BUT OVERALL GENERAL THINKING REMAINS WITH ISOLATED TO
SCATTERED CONVECTION TUESDAY AFTERNOON/EVENING. INTO THE END OF THE
PERIOD ACTIVITY WILL TAPER OFF WITH THE LOSS OF DAYTIME HEATING.
EXPECT HIGHS ON MONDAY AND TUESDAY TO BE IN THE MID 80S ALONG THE
COAST...INCREASING TO THE UPPER 80S INLAND AND LOWER 90S IN THE
WESTERN SC COUNTIES. OVERNIGHT LOWS WILL BE IN THE LOWER 70S MONDAY
INTO TUESDAY...WITH A FEW DEGREES HIGHER OVERNIGHT TUESDAY AS A MORE
WARM AND MOIST AIRMASS RETURNS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 PM SUNDAY...HOT BUT UNSETTLED FOR THE LAST HALF OF THE
WEEK AS BERMUDA TYPE HIGH PRESSURE AND SUBTLE TROUGHING ALOFT
COMBINE IN A RICH THETA-E ENVIRONMENT. THIS SUPPORTS TEMPS SEVERAL
DEGREES ABOVE CLIMO...WIDESPREAD 90S FOR HIGHS...LOW 70S FOR
LOWS...WITH HIGH CHC POP FOR DIURNAL TSTMS EACH DAY. TSTMS WILL
LIKELY BE MORE WIDESPREAD THAN JUST TYPICAL SUMMERTIME ACTIVITY
THANKS TO WEAK IMPULSES MOVING ALOFT...FURTHER ENHANCING PIEDMONT
TROUGH AND SEA BREEZE CONVECTION. IT IS INTERESTING TO NOTE THAT
GUIDANCE HAS BACKED OFF A BIT ON CONVECTION THU/FRI THANKS TO
MID-LEVEL DRYING...BUT THIS IS A NEW SOLUTION...AND WITH THE PATTERN
RELATIVELY UNCHANGED WED-FRI...WILL CONTINUE WITH INHERITED HIGH CHC
EACH DAY. BY THE WKND...RIDGING BLOSSOMS ACROSS THE SOUTHEAST...BUT
A WEAK COLD FRONT WILL TRY TO CROSS THE AREA ON SUNDAY. WILL
MAINTAIN SLIGHTLY LOWERED POP THANKS TO SUBSIDENCE BENEATH THE
RIDGE...WITH TEMPS REMAINING MOSTLY UNCHANGED. THE EXCEPTION MAY BE
SUNDAY IF FROPA OCCURS...BUT FOR NOW WILL EXPECT THE FRONT TO GET
HUNG UP TO THE NORTH AND KEEP TEMPS ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
AS OF 18Z...THE HRRR MODEL HAS BEEN PRETTY CONSISTENT IN BRINGING
DOWN CONVECTION FROM THE MOREHEAD CITY REGION ACROSS THE BI-STATE
REGION THIS AFTN. LATEST 88D TRENDS INDICATE CONVECTION HAS INCHED
CLOSER BUT REMAINS ISOLATED IN COVERAGE. AT THIS PACE...THE ILM
TERMINAL MAY EXPERIENCE A CLAP OF THUNDER WITH AN OUTSIDE SHOT FOR
THE MYRTLES TO EXPERIENCE CONVECTION PRIOR TO THE DAYS INSOLATION
COMING TO AN END. LOOK FOR POSSIBLE MVFR VISIBILITIES IN THE
TSHOWERS. FOR TONIGHT...VFR WITH A PARTLY CLOUDY SKY WITH THE
EXCEPTION OF POSSIBLE MVFR CONDITIONS FROM REDUCED VSBY FROM FOG
AFTER MIDNIGHT. FOR MONDAY...BECOMING VFR WITH ISOLATED POPS BY
LATE MORNING.
EXTENDED OUTLOOK...VFR MONDAY. AFTERNOON AND EVENING SHOWERS
EXPECTED TUESDAY THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SUNDAY...BROAD SFC LOW PARTIALLY ENCOMPASSING THE ILM
COASTAL WATERS...IS PROGGED TO PUSH FURTHER OFFSHORE THIS AFTERNOON
WHILE THE FRONTAL BOUNDARY SINKS FURTHER SOUTHWARD IN ITS WAKE. WILL
CONTINUE THE WINDS TRANSITIONING FROM A WNW-NNW TO NNE-ENE AS THE
SFC RIDGING FROM THE NORTHEAST WORKS ITS WAY ACROSS THE CAROLINAS
THIS AFTN AND TONIGHT. WIND SPEEDS AROUND 10 KT...BUT COULD SEE A
SOLID 15 KT TONIGHT ACROSS THE ILM NC WATERS FROM THE BRIEF SFC PG
TIGHTENING AND ASSOCIATED WEAK POST FRONTAL SURGE. SIGNIFICANT SEAS
WILL RUN 2 TO 3 FT...WITH A FEW 4 FOOTERS POSSIBLE ACROSS THE ILM NC
WATERS FROM CAPE FEAR NORTHWARD LATE TONIGHT. WIND DRIVEN WAVES
EXHIBITING 4 TO 6 SECOND PERIODS TO DOMINATE THE SIGNIFICANT SEAS.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...AN OFFSHORE PROGRESSING HIGH PRESSURE SYSTEM
OFF THE NEW ENGLAND COAST WILL ALLOW FOR NORTHEAST TO EAST WINDS
EARLY ON MONDAY 10 TO 12 KTS TO VEER AND BECOME EAST-SOUTHEASTERLY
INTO THE EVENING HOURS...DROPPING TO A SOLID 10 KTS AND SLIGHTLY
LOWER TOWARDS THE COAST. ON TUESDAY...EAST-SOUTHEAST WINDS BECOME
SOUTHWEST BY EVENING AS BERMUDA HIGH PRESSURE BUILDS IN...WITH WINDS
10 TO 15 KTS. AS FOR SEAS...EXPECT 1 TO 3 FT THROUGHOUT THE PERIOD.
LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 PM SUNDAY...LARGE HIGH PRESSURE WELL OFFSHORE WILL
MAINTAIN ITS INFLUENCE THROUGH THE EXTENDED...PRODUCING UNIFORM
WIND/WAVE CONDITIONS EACH DAY. AS THIS HIGH SITS OFFSHORE...RETURN
FLOW WILL ENVELOP THE WATERS...WITH SW WINDS OF 10-15 KTS COMMON
THROUGH THE PERIOD. ALTHOUGH A GROUND SWELL WILL SLOWLY AMPLIFY
THROUGH LATE WEEK...THE WAVE SPECTRUM WILL BE DOMINATED BY 5-SEC SW
WIND WAVES...CREATING 2-4 FT SEAS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...SGL
LONG TERM...JDW
AVIATION...DCH/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
125 PM EDT SUN JUN 22 2014
.SYNOPSIS...
LOW PRESSURE WILL PUSH A FRONT INTO THE REGION THIS MORNING. THIS
FRONT WILL STRUGGLE TO MOVE FURTHER SOUTH DURING THE DAY TODAY.
WEAK HIGH PRESSURE WILL EXTEND SOUTH INTO THE CAROLINAS...BUT THE
RISK OF SHOWERS AND THUNDERSTORMS WILL CONTINUE EACH DAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1110 AM SUNDAY...LATEST SATELLITE IMAGERY AND SFC OBS
INDICATE CU/SC DECK OF CLOUDS HAVE DEVELOPED AND/OR OVERSPREAD THE
AREA. HAVE CONTINUED THE 20-30 MAINLY RESULTANT WIND/SEA BREEZE
TYPE POPS THRU EARLY EVENING. THE BEST INSTABILITY WILL LIE
CLOSER TO THE FRONT WITH THE SEA BREEZE/FRONTAL BOUNDARY
INTERACTION PROVIDING LIFT. THE ILM SC COUNTIES WILL BE
HIGHLIGHTED WITH THE SLIGHTLY BETTER CHANCE FOR CONVECTION. NO
CHANGES TO THE MAX TEMPS...WITH MAINLY 80S ACROSS THE ILM NC
CWA...WITH 90S ACROSS THE ILM SC CWA.
PREVIOUS DISCUSSION.................................
AS OF 3 AM SUNDAY...WEAK COLD FRONT WILL DROP THOUGH
THE AREA TODAY AND COULD RESULT IN ISOLATED TO SCATTERED SHOWERS
AND STORMS...ESPECIALLY NEARER THE COAST DUE TO THE SEA BREEZE AND
OVER SOUTHERN AREAS WHERE INSTABILITY WILL BE THE GREATEST. HIGHS
TODAY WILL RANGE FROM THE UPPER 80S TO LOWER 90S WITH THE HIGHEST
NUMBERS EXPECTED SOUTH AND WEST. MINS TONIGHT WILL FALL TO THE
LOWER 70S EXCEPT A FEW UPPER 60S ALONG THE NORTHERN TIER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...HIGH PRESSURE BUILDS DOWN THE COAST EARLY MON AS
WEAK FRONT REMAINS STALLED WELL SOUTH OF THE AREA. THE HIGH WILL
SHIFT EAST OF NEW ENGLAND CURING THE DAY WITH LOW LEVEL NORTHEAST
FLOW IN THE MORNING BECOMING EASTERLY BY AFTERNOON. AT THE SAME TIME
THE MID LEVEL PATTERN WILL BE TRANSITIONING TO BRIEF WEAK RIDGING.
HEIGHT RISES DURING THE DAY COMBINED WITH NORTHEAST TO EAST LOW
LEVEL FLOW WILL WORK TO LIMIT CONVECTION. THERE WILL BE DEEP
MOISTURE IN PLACE WITH PRECIPITABLE WATER VALUES IN THE 1.6 TO 1.8
INCH RANGE...ABOVE NORMAL FOR LATE JUNE. DIURNAL HEATING WILL BE
ABLE TO GENERATE SOME ISOLATED DEEPER CONVECTION...ESPECIALLY INLAND
SC. WILL CONTINUE TO CARRY INHERITED SLIGHT CHC POP EVERYWHERE
EXCEPT FOR CHC POP ACROSS INLAND SC WHERE TEMPS WILL BE WARMEST AND
LOW LEVEL CONVERGENCE IS STRONGEST. HIGHS WILL END UP A LITTLE BELOW
CLIMO MON WHILE LOWS WILL CONTINUE TO RUN NEAR TO SLIGHTLY ABOVE
CLIMO.
WEAK SHORT DURATION MID LEVEL RIDGE BUILDS OVER THE SOUTHEAST FOR
TUE. ALTHOUGH THIS FEATURE WILL OFFER SOME RESISTANCE TO UPWARD
MOTION THE SEA BREEZE AND WEAK PIEDMONT TROUGH WILL BE ABLE TO
GENERATE SOME DEEP CONVECTION. PRECIPITABLE WATER VALUES REMAIN
HIGH...OVER 2 INCHES FORECAST FOR MUCH OF THE AREA...AND LOW LEVEL
WARM ADVECTION WILL PUMP PLENTY OF WARM MOIST AIR INTO THE REGION.
THERE WILL ALSO BE A WEAK SHORTWAVE MOVING NORTHEAST FROM THE GULF
OF MEXICO TUE AFTERNOON. CURRENT TIMING HAS BEST PVA COINCIDENT WITH
PEAK HEATING. THUS PLAN TO MAINTAIN INHERITED CHC POP FOR MUCH OF
THE AREA. HIGHS WILL BE NEAR CLIMO TUE WITH LOWS RUNNING SLIGHTLY
ABOVE CLIMO.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...PERIOD CONTINUES TO LOOK UNSETTLED WITH PIEDMONT
TROUGH AND SEA BREEZE BEING QUITE ACTIVE. PATTERN ALOFT WILL RANGE
FROM WEAK TROUGHING TO ZONAL FLOW INTO THE WEEKEND BEFORE MID LEVEL
RIDGE STARTS TO BUILD OVER THE SOUTHEAST. FORECAST SOUNDINGS SHOW
PLENTY OF DEEP MOISTURE IN PLACE FOR THE WEEK WITH PRECIPITABLE
WATER VALUES CLOSE TO AND EVEN EXCEEDING 2 INCHES. THERE WILL BE
SEVERAL WEAK SHORTWAVES CROSSING THE SOUTHEAST DURING THE PERIOD.
TIMING THESE IS DIFFICULT AT BEST BUT EACH WILL HAVE THE ABILITY TO
ENHANCE DIURNAL CONVECTION. PRECIP CHANCES WILL REMAIN ELEVATED WITH
POP VALUES RANGING FROM 40 TO 50 FOR MUCH OF THE PERIOD.
TEMPERATURES WILL RUN ABOVE CLIMO THROUGH THE PERIOD. HIGHS WILL
REGULARLY EXCEED 90 IN MOST AREAS WITH LOWS IN THE LOW TO MID 70S.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 18Z...THE HRRR MODEL HAS BEEN PRETTY CONSISTENT IN BRINGING
DOWN CONVECTION FROM THE MOREHEAD CITY REGION ACROSS THE BI-STATE
REGION THIS AFTN. LATEST 88D TRENDS INDICATE CONVECTION HAS INCHED
CLOSER BUT REMAINS ISOLATED IN COVERAGE. AT THIS PACE...THE ILM
TERMINAL MAY EXPERIENCE A CLAP OF THUNDER WITH AN OUTSIDE SHOT FOR
THE MYRTLES TO EXPERIENCE CONVECTION PRIOR TO THE DAYS INSOLATION
COMING TO AN END. LOOK FOR POSSIBLE MVFR VISIBILITIES IN THE
TSHOWERS. FOR TONIGHT...VFR WITH A PARTLY CLOUDY SKY WITH THE
EXCEPTION OF POSSIBLE MVFR CONDITIONS FROM REDUCED VSBY FROM FOG
AFTER MIDNIGHT. FOR MONDAY...BECOMING VFR WITH ISOLATED POPS BY
LATE MORNING.
EXTENDED OUTLOOK...VFR MONDAY. AFTERNOON AND EVENING SHOWERS
EXPECTED TUESDAY THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1130 AM SUNDAY...BROAD SFC LOW PARTIALLY ENCOMPASSING THE
ILM COASTAL WATERS...IS PROGGED TO PUSH OFFSHORE THIS AFTERNOON
WHILE THE FRONTAL BOUNDARY SINKS FURTHER SOUTHWARD IN ITS WAKE.
WILL CONTINUE THE WINDS TRANSITIONING FROM A WNW-NNW TO NNE-ENE AS
THE SFC RIDGING FROM THE NORTHEAST WORKS ITS WAY SW ACROSS THE
CAROLINAS THIS AFTN AND TONIGHT. COULD SEE A SOLID 15 KT TONITE
ACROSS THE ILM NC WATERS FROM THE BRIEF SFC PG TIGHTENING AND
ASSOCIATED WEAK POST FRONTAL SURGE. SIGNIFICANT SEAS 2 TO 3
FT...WITH A FEW 4 FOOTERS POSSIBLE ACROSS THE ILM NC WATERS FROM
CAPE FEAR NORTHWARD TONIGHT.
PREVIOUS DISCUSSION.................................
AS OF 3 AM SUNDAY...WEST TO NORTHWEST WINDS OF 10 TO 15 KT AROUND
DAYBREAK WILL BECOME NORTH TO NORTHEAST TODAY AND A LITTLE MORE
EASTERLY TONIGHT. SEAS OF 3 FT OR LESS ARE EXPECTED THROUGH THE
PERIOD.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...NORTHEAST FLOW AT THE START OF THE PERIOD WILL
SLOWLY VEER TO EASTERLY DURING MON AS HIGH OVER NEW ENGLAND MOVES
OFF THE COAST. GRADIENT WILL BE SUCH THAT SPEEDS REMAIN 10 TO 15 KT
WITH SEAS 1 TO 3 FT. BERMUDA HIGH BUILDS BACK WEST ON TUE WITH
SOUTHEAST FLOW IN THE MORNING BECOMING SOUTHWEST BY TUE EVENING.
SPEEDS WILL REMAIN IN THE 10 TO 15 KT RANGE WITH 1 TO 3 FT SEAS
CONTINUING.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...BERMUDA HIGH WILL MAINTAIN SOUTHWEST FLOW OVER
THE WATERS THROUGH THE PERIOD. SPEEDS WILL BE IN THE 10 TO 15 KT
RANGE FOR MUCH OF THE PERIOD BUT COULD PERIODICALLY EXCEED 15
KT...ESPECIALLY ALONG THE COAST. SEAS W TO 3 FT ON WED WILL BUILD TO
2 TO 4 FT THU AS SOUTHERLY SWELL STARTS TO BECOME A LITTLE MORE
PROMINENT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...III
NEAR TERM...DCH/RAN
SHORT TERM...III
LONG TERM...III
AVIATION...DCH/DL
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1246 PM CDT SUN JUN 22 2014
.UPDATE...
UPDATED FOR 18Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1046 AM CDT SUN JUN 22 2014/
UPDATE...
MIDMORNING GOES IR IMAGERY SHOWED A COUPLE OF MCS THIS MORNING...
OVER EASTER NE AND IA AND ANOTHER OVER NORTH TX. NEITHER MCS WAS
UPSTREAM OF THE MIDSOUTH...AND THE TX MCS HAD REARWARD PROPAGATION
COMPONENT. NEARER TO THE MIDSOUTH...SOME MIDLEVEL CLOUD COOLING
WAS NOTED ON IR OVER CENTRAL AND NORTH MS...PERHAPS AN INDICATION OF
ENHANCED MIDLEVEL LIFT FROM A WEAK 250MB JET STREAK OVER THE
ARKLAMISS REGION.
TODAY/S RAIN CHANCES FOR THE MIDSOUTH APPEAR A LITTLE MORE LIMITED
THAN SATURDAY...GIVEN THE LACK OF A DISTINCT MCS OR MIDLEVEL
SHORTWAVE TROF. 13Z HRRR MODEL DEPICTED AFTERNOON THUNDERSTORM
COVERAGE TO BE ISOLATED AT BEST. HOWEVER...12Z NAM BUFR SOUNDINGS
SHOW THE BOUNDARY LAYER UNCAPPED BY 18Z...WITH SURFACE BASED CAPE
IN EXCESS OF 2000 J/KG AREAWIDE.
IN THE ABSENCE OF A SHORTWAVE TROF OR MCV...MESOSCALE PROCESSES
/DIFFERENTIAL HEATING...OUTFLOW BOUNDARY INTERACTIONS/ WILL
LIKELY DETERMINE WHERE AND IF THUNDERSTORMS INITIATE AND SUBSEQUENTLY
EVOLVE.
MOST RECENT FORECAST UPDATED INCLUDED MINOR ADJUSTMENTS TO TIMING
OF POPS AND TO EDGE AFTERNOON TEMPS UP A BIT NORTH AND EAST OF THE
MEMPHIS METRO.
PWB
PREV DISCUSSION... /ISSUED 633 AM CDT SUN JUN 22 2014/
DISCUSSION...
UPDATED FOR THE 12Z AVIATION DISCUSSION
PREV DISCUSSION... /ISSUED 352 AM CDT SUN JUN 22 2014/
DISCUSSION...
THE LONGEST DAY OF THE YEAR HAS COME TO AN END AND ITS ANOTHER
QUIET SUMMER NIGHT ACROSS THE MIDSOUTH. TEMPERATURES HAVE FALLEN
INTO THE UPPER 60S IN THE COOLEST LOCATIONS ACROSS THE MIDSOUTH
WITH MOST AREAS IN THE LOW TO MIDDLE 70S. MORNING LOWS SHOULD BE
IN THE UPPER 60S TO NEAR 70 DEGREES AREA WIDE. PATCHY FOG HAS
DEVELOPED...AND VISIBILITY HAS DROPPED AS LOW AS 1/4 MILE IN
ALCORN COUNTY MISSISSIPPI...BUT THAT IS THE EXCEPTION. MOST AREAS
ARE ONLY EXPERIENCING SLIGHT REDUCTIONS TO VISIBILITY IF ANY. WILL
MONITOR ADDITIONAL FOG DEVELOPMENT...BUT DO NOT ANTICIPATE THE
NEED FOR ANY KIND OF ADVISORY.
WE WILL LIKELY SEE ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
DEVELOP THIS AFTERNOON. WIDESPREAD SEVERE STORMS ARE NOT
EXPECTED...BUT ISOLATED SEVERE STORMS AS WELL AS NUMEROUS STRONG
STORMS ARE POSSIBLE. THE MAIN THREAT FROM ANY STRONG TO SEVERE
STORMS WILL BE WINDS...MAINLY IN THE FORM OF WET MICROBURSTS.
GUIDANCE SUGGESTS STORMS WILL DEVELOP QUICKLY AFTER SUNRISE. THE
GFS SHOWS A FAIRLY DECENT VORT MAX TRACKING OUT OF SOUTHERN
ARKANSAS INTO CENTRAL MISSISSIPPI THIS AFTERNOON...AND THERE IS
SOME INDICATION ON SATELLITE OF THIS FEATURE IN SOUTHERN ARKANSAS
RIGHT NOW. THIS MAY ENHANCE STORMS ACROSS NORTH MISSISSIPPI...BUT
FOR THE MOST PART WE ARE NOT TARGETING ANY SPECIFIC PORTION OF THE
MIDSOUTH FOR ENHANCED COVERAGE OR STRENGTH OF STORMS. DEW POINTS
IN THE LOW TO MIDDLE 70S WILL HELP TO PRODUCE A VERY UNSTABLE
ENVIRONMENT FEATURING CAPE VALUES INTO THE 2500-3000 J/KG RANGE
THIS AFTERNOON AND LI`S BELOW -7C. MOISTURE LEVELS ALOFT ARE ALSO
HIGH...BOTH LITTLE ROCK AND NASHVILLE AFTERNOON SOUNDINGS HAD PW
VALUES AROUND 1.5 INCHES. AS A RESULT...HEAVY RAINFALL IS LIKELY.
STORM MOTION WILL BE SLOW...LIKELY DRIFTING EAST TO SOUTHEAST SO
ISOLATED FLOODING PROBLEMS ARE POSSIBLE.
ENHANCED RAIN CHANCES WILL REMAIN IN THE FORECAST THROUGH MIDWEEK
WITH THE GREATEST CHANCES MONDAY AFTERNOON THROUGH TUESDAY
AFTERNOON AS A SEASONABLY STRONG SHORTWAVE TROUGH SHIFTS OUT OF
THE CENTRAL/SOUTHERN PLAINS ACROSS THE MISSISSIPPI RIVER VALLEY.
ONCE AGAIN...NO WIDESPREAD SEVERE STORMS ARE EXPECTED...BUT ANY STORMS
ARE LIKELY TO BECOME STRONG WITH OUR CURRENT ATMOSPHERIC
CONDITIONS AND ISOLATED SEVERE STORMS ARE POSSIBLE. DAMAGING WIND
IS THE MOST LIKELY THREAT. HIGH TEMPERATURES SHOULD BE KEPT DOWN A
BIT ESPECIALLY MONDAY AND TUESDAY. HIGHS MAY EVEN REMAIN IN THE
LOW 80S IF THUNDERS STORMS AND CLOUDS ARE NUMEROUS.
AFTER MIDWEEK...AS THE SHORTWAVE SHIFTS EAST OF THE MIDSOUTH A
WEAK RIDGE AND SURFACE HIGH PRESSURE WILL TRY TO REASSERT ITS
INFLUENCE ACROSS THE MIDSOUTH. EXPECT LESS RAIN THURSDAY INTO THE
WEEKEND AND SLIGHTLY WARMER TEMPERATURES. GUIDANCE IS NOT IN
PERFECT AGREEMENT WITH THIS SOLUTION. THE ECMWF FEATURES A
STRONGER RIDGE CENTERED FARTHER NORTH AND WEST WHICH WOULD RESULT
IN AN EVEN WARMER AND DRIER FORECAST FRIDAY THROUGH THE WEEKEND.
FOR NOW WILL PLAY THE MIDDLE OF THE ROAD...HOLDING ONTO SLIGHT
CHANCE TO LOW CHANCE POPS DURING THE END OF THE FORECAST PERIOD
AND NEAR NORMAL TEMPERATURES.
30
&&
.AVIATION...
18Z TAF CYCLE
AFTERNOON CONVECTION HAS ALREADY FIRED UP IN THE SOUTHERNMOST
PORTION OF THE CWA WITH CAPE VALUES ALREADY EXCEEDING 3000 J/KG AT
ALL SITES ACCORDING TO SPC MESOANALYSIS. CURRENT THINKING IS THAT
NORTHERN MS WILL HAVE THE BEST CHANCE FOR AFTERNOON STORMS TODAY AS
500MB HEIGHT FALLS WILL BE THE GREATEST THERE. NONETHELESS...HAVE
INCLUDED A VCTS AT ALL SITES UNTIL AFTER SUNSET TO ACCOUNT FOR THE
UNCERTAINTY REGARDING TODAYS CONVECTION. WILL AMEND AS NECESSARY
TO ACCOUNT FOR STORMS THAT MAY DEVELOP WITHIN THE VICINITY OF THE
SITES.
ZDM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
110 PM CDT SUN JUN 22 2014
.DISCUSSION...
18Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
REGIONAL ATMOSPHERE IS MOIST AND UNSTABLE ENOUGH TO SUPPORT
WIDELY SCATTERED THUNDERSTORMS...ESPECIALLY NORTH AND EAST OF
METRO TERMINALS. RECENT HIGH OVERCAST HAS LIMITED OVERALL CONVECTIVE
COVERAGE...RETARDING HEATING INTO THE MID TO UPPER 80S. MID TO
LATE AFTERNOON CLOUD BREAKS WILL ALLOW SFC TEMPERATURES TO HIT OR
EXCEED 90F...INCREASING THE PROBABILITY FOR RETURNING -TSRA. DRY
MID-LEVEL AIR WILL WIN OUT THROUGH MID TO LATE PERIOD ...MID TO
HIGH LEVEL CLOUDINESS OVERNIGHT WITH PRECIPITATION PROBS BECOMING
TO LOW TO MENTION VICINITY. 31
&&
.PREV DISCUSSION... /ISSUED 1030 AM CDT SUN JUN 22 2014/
UPDATE...
SEE MORNING UPDATE.
DISCUSSION...
AT 9 AM...SFC HIGH PRESSURE WAS LOCATED OVER SW LOUISIANA AND LOW
PRESSURE WAS OVER WESTERN KANSAS. VIS SATELLITE SHOWED EXTENSIVE
CLOUD COVER OVER MOST OF THE STATE WITH SOME BREAKS IN THE CLOUDS
OVER SE TX. 12Z SOUNDINGS SHOW PW VALUES AROUND 1.70 INCHES...
CONVECTIVE TEMPS BETWEEN 86 AND 90 DEGREES...NO CAPPING AND WITH A
LAYER OF DRY AIR BETWEEN 800 MB AND 600 MB. AT 850 MB...A SWATH OF
DEEP MOISTURE EXTENDED ACROSS CENTRAL TEXAS EXTENDING FROM DODGE
CITY KANSAS TO NORTHERN MEXICO. AN 850 MB RIDGE WAS OVER THE
NORTHERN GULF AND EXTENDED NORTH INTO CENTRAL ARKANSAS. AT 700
MB...DEEPER MSTR AND A WEAK 700 MB TROUGH AXIS EXTENDED FROM NE
TEXAS TO THE BIG BEND. AT 250 MB...A WEAK HIGH WAS OVER NORTHERN
MEXICO WITH A SPEED MAX OVER NORTH CENTRAL MEXICO. A WEAK S/WV
EXTENDED FROM SOUTH CENTRAL KANSAS TO NE TEXAS.
BOTH THE ECMWF AND THE GFS SHOW SE TX IN A WEAK LFQ THIS AFTN AND
THIS IS SUPPORTED BY THE 12Z 250 MB ANALYSIS. CONSIDERING THE
LIFT PROVIDED BY THE SPEED MAX...A WEAK SPLIT IN THE UPPER JET...
DIFFERENTIAL HEATING AND WEAK PVA...FEEL CONVECTIVE POTENTIAL WILL
BE INCREASING THIS AFTN. THE RAP 13 AND HRRR SHOW THE BEST
POTENTIAL OVER THE NE ZONES THIS AFTN SO HAVE RAISED POPS OVER THE
NE. ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE
HEAVY RAIN AS STORM MOTION WILL BE ON THE SLOW SIDE. CLOUDS WILL
WREAK HAVOC WITH MAX TEMPS BUT ANY BREAK IN THE CLOUD COVER WILL
ALLOW TEMPS TO WARM QUICKLY. LEFT TEMP FCST AS IS. OVERALL...ONLY
MINOR CHANGES AS PREV FCST HAD THINGS WELL IN HAND. 43
&&
PREV DISCUSSION... /ISSUED 626 AM CDT SUN JUN 22 2014/
DISCUSSION...
SEE AVIATION.
AVIATION...
SEEING A BAND OF SHRA APPROACHING NW AREAS OF SE TX THIS MORNING
WHICH WILL AFFECT CLL 12-14Z. BY MID MORNING EXPECT TO SEE SCT
SHRA ACROSS MOST OF THE AREA. EXPECT ISOLATED/SCATTERED TSRA
AROUND THIS AFTERNOON...ESPECIALLY IN THE VICINITY OF A WEAK SEA
BREEZE. AMPLE HIGH CLOUDS WILL CONTINUE THROUGH THE DAY. 33
&&
PREV DISCUSSION... /ISSUED 440 AM CDT SUN JUN 22 2014/
DISCUSSION...
TX AREA RADAR SHOWS QUITE A BIT OF SHOWER ACTIVITY OVER N TX
WHICH MAY BE THE RESULT OF A SHORTWAVE TROUGH AND OLD MCV THAT IS
SHEARING OUT OVER THE AREA. CLOUD COVER HAS HELD TEMPS IN THE MID
70S FOR MUCH OF THE AREA THIS MORNING SO NOT QUITE AS COOL AS
YESTERDAY. BASED ON 00Z SOUNDINGS LCH AND CRP ARE SHOWING PRECIP
WATER VALUES OF 1.5 TO 1.7 INCHES RESPECTIVELY. THINK PRECIP WATER
VALUES WILL BE CLOSER TO 1.7 INCHES OVER MUCH OF THE AREA TODAY.
THE 00Z 500MB ANALYSIS SHOWS 589/590 DM HEIGHTS ALONG THE NW GULF
COAST SO THINK RIDGE IS MOVING MORE INTO THE GULF TOWARDS THE BAY
OF CAMPECHE. HEIGHTS HAVE COME DOWN SOME WHICH SHOULD SUPPORT MORE
SHOWER AND THUNDERSTORM ACTIVITY TODAY ESPECIALLY WITH HIGHER
MOISTURE. FORECAST WILL GO WITH MAINLY 30/40 POPS TODAY. LOOKING
AT STORM TOTAL ACCUM RAINFALL FROM YESTERDAY...FEW STRONGER STORMS
COULD EASILY DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME.
MAIN IMPACT WILL BE LOCALIZED STREET FLOODING WITH THE HEAVY
RAINFALL AND GUSTY WINDS FROM OUTFLOWS.
BY MONDAY BROAD TROUGHING BECOMES MORE ESTABLISHED OVER TX AND
REALLY NO HINT OF ANY RIDGING. MODELS OUTPUT MEAGER RAINFALL
AMOUNTS AND KEEP POPS LOW SO WILL ONLY GO WITH 20/30 POPS. IT
LOOKS LIKE PRECIP WATER VALUES MAY DROP CLOSER TO 1.5 INCHES ON
MONDAY BEFORE SURGING BACK UP ON TUE/WED. TUE LOOK FOR HIGHER
MOISTURE VALUES AND TROUGHING BECOMING MORE PRONOUNCED. SHORTWAVE
NOW OVER CALIFORNIA WILL HAVE MADE ITS WAY ACROSS THE S ROCKIES
INTO THE S PLAINS BY THIS TIME. THIS MAY HELP BRING HEIGHTS DOWN
BELOW 588 DM AT 500MB. PRECIP WATER VALUES MAY BE APPROACHING 2
INCHES BY WED PER NAM/GFS SOLUTIONS. DECIDED TO GO A BIT HIGHER
WITH POPS ON TUE INTO WED. WED LOOKS TO BE MORE WET BUT WILL KEEP
POPS AT 50 FOR NOW. QUITE POSSIBLE TO HAVE SCATTERED TO WIDESPREAD
CONVECTION EACH DAY FROM WEDNESDAY THROUGH THE END OF THE WEEK.
BEST CHANCES OF RAIN LOOK TO BE WED/THUR/FRI WITH BROAD TROUGHING
ALOFT AND PRECIP WATER VALUES NEAR 1.9 TO 2 INCHES EACH DAY. IT
WILL NOT TAKE MUCH HEATING FOR CONVECTION TO DEVELOP EACH DAY.
WITH THAT MUCH MOISTURE...MAIN CONCERN WILL BE LOCALLY HEAVY
RAINFALL RESULTING IN LOCALIZED FLOODING. QUITE POSSIBLE THAT
URBAN AREAS COULD SEE STREET FLOODING AS A RESULT. BAYOUS COULD
RESPOND WITH RAPID RISES AS WELL. IMPACTS COULD BE MADE WORSE BY
ANY TRAINING STORMS BUT TOO EARLY TO DETERMINE THOSE KINDS OF
DETAILS JUST YET.
OVERALL EXPECT TEMPERATURES TO BE IMPACTED BY CLOUD COVER AND
CONVECTION. STILL SUMMER TIME SO IT DOES NOT TAKE MUCH TO REACH
LOW 90S FOR MAX TEMPS. THIS ALSO MEANS CONVECTIVE TEMPS SHOULD BE
REACHED AND TRIGGER CONVECTION. FORECAST WILL KEEP TEMPS IN THE
90-92F RANGE BUT COULD SEE UPPER 80S FOR HIGHS SHOULD SCATTERED TO
WIDESPREAD CONVECTION DEVELOP. LOW TEMPS IN THE LOW/MID 70S LOOK
ON TRACK AS WELL ESPECIALLY WITH ANY RAIN COOLED AIR THAT
DEVELOPS. STILL NOT BAD HAVING TEMPS NEAR NORMAL FOR THE END OF
JUNE. 39
&&
MARINE...
PERSISTENT ONSHORE FLOW WILL CONTINUE THROUGH THE WEEK. SOUTHERLY
WINDS WILL APPROACH SCEC CRITERIA WELL OFFSHORE TONIGHT AND MONDAY
NIGHT...BUT WILL LIKELY STAY JUST BELOW. BY TUESDAY NIGHT THE
PRESSURE GRADIENT TIGHTENS AND WE WILL LIKELY SEE 15 TO 20 KT
ONSHORE WINDS OFFSHORE. BY MID-WEEK WINDS WILL INCREASE FURTHER
AND SEAS WILL BUILD. BUMPED WINDS AND SEAS WED-FRI TO REFLECT THE
CURRENT GFS...AND SCA CONDITIONS ARE POSSIBLE LATE THIS WEEK
OFFSHORE. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 75 91 76 90 74 / 20 20 20 40 20
HOUSTON (IAH) 76 92 77 90 75 / 20 20 20 40 20
GALVESTON (GLS) 80 88 80 87 80 / 10 20 20 30 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1230 PM CDT SUN JUN 22 2014
.AVIATION...
ISOLD SHRA/TSRA ARE POSSIBLE THIS AFTERNOON AND AGAIN ON MONDAY.
HOWEVER...PROBS ARE TOO LOW TO MENTION IN THE TAFS. MVFR CIGS OVER
THE HILL COUNTRY TO ALONG THE RIO GRANDE INCLUDING KDRT WILL RISE
TO VFR BY 20Z. OTHERWISE...VFR SKIES WILL PREVAIL THIS AFTERNOON
INTO EVENING. STRATUS WITH MVFR CIGS CAN BE EXPECTED TO DEVELOP BY
AROUND 06Z...SPREADING TO ALL AREAS OVERNIGHT. PATCHY IFR CIGS ARE
POSSIBLE OVER THE HIGHER HILL COUNTRY TERRAIN AND FOR AN HOUR OR
TWO ELSEWHERE MONDAY MORNING. CIGS RISE TO VFR LATE MONDAY MORNING
INTO THE AFTERNOON. S TO SE WINDS 10 TO 15 KTS WILL DECREASE TO 10
KTS OR LESS TONIGHT AND THEN INCREASE TO 10 TO 15 KTS MONDAY. OCNL
GUSTS TO 22 KTS ARE POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 643 AM CDT SUN JUN 22 2014/
AVIATION...ISOLATED TO SCATTERED LOW TOP SHOWERS MOVING E-NE ACROSS
SOUTH CENTRAL TEXAS THIS MORNING. ANY OF THE TERMINAL SITES MIGHT SEE
A PASSING SHOWER BUT IMPACTS WILL LIMITED TO MVFR CEILINGS BETWEEN
1500-2500 FEET. MULTI-LAYERED CLOUDS TO REMAIN ACROSS THE AREA
WITH THE LOWER CLOUDS LIFTING AND BREAKING UP AROUND OR SHORTLY AFTER
16Z. ISOLATED SHOWERS AND THUNDERSTORMS TO REDEVELOP THIS
AFTERNOON BUT CHANCE REMAINS LOW FOR ANY ONE TO PASS ACROSS
TERMINALS SO WILL LEAVE OUT OF TAFS AT THIS TIME. LOW LEVEL
INVERSION OVERNIGHT WITH MVFR CIGS EXPECTED TO RETURN ALONG THE I
35 CORRIDOR THEN SPREAD WEST. A LIGHT TO MODERATE PRESSURE GRADIENT
TO MAINTAIN AND SOUTHEAST TO SOUTH FLOW AT SPEEDS UNDER 20 KNOTS.
PREV DISCUSSION... /ISSUED 347 AM CDT SUN JUN 22 2014/
SHORT TERM (TODAY THROUGH MONDAY)...
A WEAK SHEAR AXIS IS DRAPED ALONG AND NW OF I-35 EARLY THIS
MORNING. LIGHT CONVECTION IS DEVELOPING ALONG THIS AXIS AND IS
DEPICTED FAIRLY WELL BY THE RECENT RUC RUNS. THE SHEAR AXIS IS
EXPECTED BY MODEL CONSENSUS TO SHIFT EAST AND POSSIBLY PUSH THE
HIGHER RAIN CHANCES AND PWAT VALUES INTO EASTERN COUNTIES LATE
TODAY WHILE MID LEVEL STABILITY BUILDS INTO WESTERN AND CENTRAL
COUNTIES. THE INCREASING STABILITY IS SUGGESTED TO BE OVER A
SHORT PERIOD... LASTING THROUGH LATE MONDAY. WITH REDUCED CLOUD
COVER EXPECTED THE MILD AFTERNOON TEMPERATURES OF TODAY SHOULD
REBOUND 2-4 DEGREES WARMER FOR MONDAY.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...
A SMALL DISTURBANCE IS EXPECTED TO TRIGGER CONVECTION OVER THE
SOUTHERN PLAINS LATE MONDAY AND POSSIBLY SEND A WEAKENING COMPLEX
OF STORMS INTO THE AREA MONDAY NIGHT INTO TUESDAY. WITH NORTHERLY
MID-LEVEL FLOW DEVELOPING DURING THIS PERIOD...SOME MODELS...
ESPECIALLY THE CANADIAN...DEVELOP A LOW PRESSURE CENTER OVER
CENTRAL TX AND AMPLIFY RAIN CHANCES INTO A POSSIBLE FLOOD PATTERN.
A MORE CONSERVATIVE BLEND OF THE DRIER GFS AND WETTER ECMWF IS
PREFERRED FOR FORECAST CONSISTENCY...BUT WILL NOTE THAT THE
BROADER WEAKNESS OVER TX IS TYPICAL FOR JUNE HEAVY RAIN EVENTS.
BASED ON MODEL CONSENSUS AN ENHANCEMENT OF DIURNAL THUNDERSTORM
ACTIVITY IS PROBABLE FOR AREAS ALONG AND EAST OF I-35 WEDNESDAY
THROUGH SATURDAY...AS EVEN THE DRIER GFS KEEPS A WEAK MID LEVEL
SHEAR AXIS OVER CENTRAL TX THROUGH AS LATE AS THURSDAY.
THE CONSENSUS OF WETTER AND DRIER MODEL SOLUTIONS IN THE EXTENDED
FORECAST CONTINUES TO KEEP TEMPERATURES RELATIVELY MILD.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 90 74 92 74 90 / 30 10 10 20 20
AUSTIN BERGSTROM INTL AIRPORT 90 73 93 73 90 / 30 10 10 20 20
NEW BRAUNFELS MUNI AIRPORT 91 74 93 73 90 / 20 10 10 10 20
BURNET MUNI AIRPORT 87 72 91 72 88 / 20 - 20 20 20
DEL RIO INTL AIRPORT 91 74 96 75 94 / 10 - 10 10 10
GEORGETOWN MUNI AIRPORT 89 73 92 73 90 / 20 10 20 20 20
HONDO MUNI AIRPORT 92 73 93 73 93 / 20 10 10 10 20
SAN MARCOS MUNI AIRPORT 90 74 92 73 90 / 20 10 10 20 20
LA GRANGE - FAYETTE REGIONAL 91 76 93 75 90 / 30 10 20 20 30
SAN ANTONIO INTL AIRPORT 90 76 93 75 90 / 20 10 10 10 20
STINSON MUNI AIRPORT 92 75 94 75 92 / 20 10 10 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...04
SYNOPTIC/GRIDS...25
PUBLIC SERVICE/DATA COLLECTION...32
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
107 PM EDT SUN JUN 22 2014
.SYNOPSIS...
WEDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA TODAY AND
TONIGHT. MOISTURE WILL RETURN AGAIN BY MONDAY...RESULTING IN A
DAILY THREAT SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY. A COLD
FRONT WILL APPROACH FROM THE NORTHWEST BY THE MIDDLE OF THE
WEEK...BRINGING IN MORE WIDESPREAD SHOWERS AND STORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 202 PM EDT SUNDAY...
A WEDGE REMAINS IN PLACE ACROSS THE PIEDMONT WITH ABUNDANT LOW
CLOUDS AND NORTHEASTERLY FLOW. ACROSS THE MOUNTAINS...LOW LEVEL
FLOW IS WESTERLY WITH LESS CLOUDS AND MORE SUNSHINE. THE
CONVERGENCE OF THESE WIND FLOWS IS ALONG THE BLUE RIDGE AND
FOOTHILL COUNTIES. ACROSS THE NORTHERN NORTH CAROLINA
FOOTHILLS...CAPE VALUES ARE AROUND 800 J/KG AND OVER THE MOUNTAINS
AROUND 500 J/KG.
HIRES MODELS DISPLAYING TWO SCENARIOS. ONE IS TO HAVE SHOWERS
DEVELOP IN THE CONVERGENCE ZONE DURING THE AFTERNOON. AS THESE
STORMS GET TALLER...STEERING FLOW WILL HAVE THEM DRIFT TO THE EAST
INTO THIS EVENING. THE SECOND SCENARIO IS TO HAVE SCATTERED
CONVECTION OVER THE OHIO VALLEY TRACK INTO THE NORTH THIS
AFTERNOON...THEN TAP HEAT AND MOISTURE AND BLOWUP MOVING EAST
ALONG THE WEDGE BOUNDARY. BOTH ARE VIABLE SOLUTIONS AND ARE
DEPICTING IN THE FORECAST GRIDS FROM A BLEND OF THE HRRR AND LOCAL
WRF. ONLY CARRYING ISOLATED TO SCATTERED THUNDERSTORMS AS SURFACE
DEW POINTS ACROSS THE MOUNTAINS ARE IN THE M50S-L60S. DEW POINTS
ACROSS THE NC FOOTHILLS ARE IN THE M/U 60S. THERE IS ALSO A FAIR
AMOUNT OF DRY AIR ALOFT.
CLOUDS IN THE EAST ARE KEEPING TEMPERATURES COOLER THIS
AFTERNOON. HAVE NOT SEEN ANY EVIDENCE THAT THESE LOW CLOUDS ARE
EXPANDING OR ERODING EARLY THIS AFTERNOON. THEREFORE WILL KEEP THE
PIEDMONT COOLER THROUGH THE REST OF THE AFTERNOON COMPARED TO
AREAS WEST. TEMPERATURES ACROSS THE FOOTHILLS AND MOUNTAINS ARE
COOLER THAN PREVIOUS COUPLE OF DAYS AND SHOULD WARM INTO THE L/M
80S THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
AS OF 300 AM EDT SUNDAY...
WEAK SURFACE HIGH PRESSURE OFF THE NEW ENGLAND COAST ON MONDAY IS
FORECAST TO DRIFT OFFSHORE TUESDAY AS NEXT SHORT WAVE TROF
APPROACHES THE BLACKSBURG FORECAST AREA FROM THE WEST...BEGINNING TO
SUBTLY FLATTEN THE UPPER RIDGE THAT WILL HAVE BUILT NORTHWEST FROM
OFF THE SOUTHEAST COAST.
SURFACE WINDS ON BACKSIDE OF DEPARTING SURFACE HIGH...AND IN ADVANCE
OF APPROACHING SURFACE TROF WILL GRADUALLY VEER INTO THE SOUTHEAST
EAST OF THE BLUE RIDGE ON MONDAY...AND INTO THE SOUTH ON TUESDAY...
WHILE WINDS REMAIN MORE SOUTHWESTERLY WEST OF THE BLUE RIDGE. THIS
CONFLUENT FLOW...WITH UPSLOPING ON BOTH THE EAST AND WEST SIDE OF
THE APPALACHIANS...COUPLED WITH WEAK WARM MOIST ADVECTION AS
TROPICAL AIRMASS SLOWLY CREEPS BACK INTO THE MID APPALACHIAN AND MID
ATLANTIC REGION WILL SUPPORT DAILY REDEVELOPMENT OF
SHOWERS/THUNDERSTORMS WITHIN AN UNCAPPED ENVIRONMENT.
DAILY DEVELOPMENT WILL LIKELY BE MAXIMIZED ALONG AND NEAR THE FLANKS
OF THE APPALACHIANS WHERE CONFLUENCE AND DIFFERENTIAL HEATING WILL
BE MAXIMIZED...WITH STORMS MORE OF A SCATTERED NATURE ELSEWHERE...
ESPECIALLY ACROSS THE NORTHEASTERN PORTION OF THE FORECAST AREA
WHERE A SLIGHTLY DRIER AND MORE STABLE AIRMASS WILL LINGER CLOSER TO
THE DEPARTING SURFACE RIDGE.
WITH GRADUAL BUILDING HEIGHTS OVER THE AREA THROUGH THE SHORT TERM
PERIOD...MID LEVEL LAPSE RATES WILL REMAIN RELATIVELY WEAK SUCH THAT
SEVERE THREAT SHOULD BE MINIMIZED AND CONFINED TO ISOLATED WIND
THREATS WHERE PRECIPITATION LOADING CAN BE MAXIMIZED. OF GREATER
CONCERN IS LACK OF SIGNIFICANT STEERING WINDS THROUGH ABOUT 15K
FEET...SUCH THAT ERRATIC DRIFTING STORM MOVEMENT MAY RESULT IN
LOCALIZED EXCESSIVE RAINFALL. WITH LACK OF SIGNIFICANT FORCING TO
SUPPORT A MORE WIDESPREAD SIGNIFICANT RAINFALL EVENT...AND ONLY
SPOTTY HEAVY RAINS RECENTLY OVER THE PAST SEVERAL DAYS...SEE NO NEED
TO POST ANY HYDROLOGIC-BASED WATCH AT THE PRESENT TIME.
ALTHOUGH SHOWER/THUNDERSTORM ACTIVITY WILL BE MAXIMIZED DURING
AFTERNOON/EVENING PERIODS...FORECAST SOUNDINGS INDICATE SUFFICIENT
INSTABILITY WILL PERSIST TO MAINTAIN PRECIPITATION THREAT EVEN LATER
AT NIGHT WHEREVER FORCED ASCENT/WEAK UPSLOPING CAN BE MAINTAINED.
THIS THREAT FURTHER SUPPORTED WITH PLENTY OF VERY WEAK AND SMALL
UPSTREAM SHORT WAVES EMBEDDED IN UPPER FLOW THAT ARE FORECAST TO
RIDE AROUND PERIPHERY OF BUILDING UPPER RIDGE THROUGH THE
PERIOD...MOST NOTABLY ON TUESDAY NIGHT AS MORE POTENT SHORT WAVE
TROF AND ASSOCIATED COOL FRONT APPROACHES THE AREA FROM THE WEST.
MOS GUIDANCE CONTINUES TO BE QUITE CONSISTENT THROUGH THE PERIOD AND
GENERALLY ACCEPTED WITH DAYTIME HIGHS MAINLY IN THE 80S...WITH 70S
CONFINED TO THE HIGHER ELEVATIONS...AND WITH OVERNIGHT LOWS
GENERALLY BE IN THE 60S. DEVIATIONS WILL LIKELY BE GOVERNED BY
LOCALIZED MORE PERSISTENT CLOUD COVER AND/OR BY COOL OUTFLOW
BOUNDARIES GENERATED BY PASSING SHOWERS/STORMS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 140 PM EDT SATURDAY...
I WOULD NOT EXPECT TOO MUCH CHANGE THIS FORECAST PERIOD. FRONTAL
BOUNDARY WILL SITUATE ITSELF NEAR THE AREA WED-THU THEN LIFT BACK
NORTH INTO FRIDAY AND SATURDAY AS HEIGHTS BUILD YET AGAIN.
OVERALL...THERE WILL BE A DAILY THREAT OF STORMS...BUT MAINLY
AFTERNOON/EVENING. AT THE MOMENT BEST THREAT OF STORMS WILL BE
WEDNESDAY WITH SHORTWAVE PIECE MOVING ACROSS DURING THE MIDDLE OF
THE DAY. EXPECT THE MODELS THIS FAR OUT TO STILL HAVE TIMING
ISSUES WITH WAVES ALONG THE SRN EDGE OF THE WESTERLIES.
NOT GOING TO SEE TOO MUCH CHANGE IN AIRMASS AS DRIER DEWPOINTS
STAY WELL NORTH OF THE MID ATLANTIC.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 205 PM EDT SUNDAY...
A FRONT WAS DRAPED FROM THE CAROLINAS BACK INTO THE TENNESSEE
VALLEY. ENOUGH HIGH PRESSURE WAS BUILDING INTO THE REGION NORTH OF
THIS SYSTEM.
IFR-MVFR CLOUDS AND EASTERLY FLOW REMAINED OVER THE PIEDMONT
(LYH- DAN) THROUGH EARLY AFTERNOON. DESPITE HIGH SUMMER SUN...THIS
WEDGE IS NOT EXPANDING OR ERODING THIS AFTERNOON. ACROSS THE
FOOTHILLS AND MOUNTAINS...THE LOW LEVEL FLOW WAS NORTHWESTERLY.
THESE TWO FLOWS CONVERGE ACROSS THE BLUE RIDGE AND THE FOOTHILLS.
SINCE THIS AREA IS OUTSIDE OF THE CLOUD BOUNDARY...DIFFERENTIAL
HEATING SHOULD ALLOW CONVECTION TO DEVELOP THIS AFTERNOON.
INSTABILITIES ARE CURRENTLY LOW WHICH SHOULD KEEP ANY CONVECTION
LIMITED TO SCATTERED AREAL COVERAGE WITH A POSSIBLE FEW STORMS
BECOMING STRONG.
ANY CONVECTION WILL MAINLY BE DIURNALLY DRIVEN AND FADE WITH LOSE
OF HEATING. ALSO WITH LOSE OF HEATING...EASTERLY FLOW AND CLOUD
DECK ACROSS THE PIEDMONT MAY EXPAND EASTWARD BRING LOW IFR-MVFR
DECK TO THE BLUE RIDGE.
EXTENDED AVIATION DISCUSSION...
DEEPER MOISTURE RETURNS NORTH...WITH BETTER COVERAGE OF
AFTERNOON/EVENING STORMS ON MONDAY ESPCLY MOUNTAINS AHEAD OF
ANOTHER UPPER TROF AND FRONT TO THE WEST. THIS BOUNDARY WILL GET
CLOSER TUESDAY INTO WEDNESDAY WITH AT LEAST DIURNAL DAILY ROUNDS
OF SHOWERS AND STORMS LIKELY TUESDAY INTO WEDNESDAY INCLUDING
PERIODS OF MVFR/IFR. MAY SEE SOME IMPROVEMENT ON THURSDAY AS THE
FRONT WASHES OUT OVERHEAD BUT STILL ENOUGH MOISTURE WITH HEATING
FOR ADDED DIURNAL CONVECTION AGAIN THURSDAY AFTERNOON WITH PERIODS
OF MVFR POSSIBLE. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE
NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE
PREVIOUS AFTERNOON.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/RCS
SHORT TERM...WERT
LONG TERM...WP
AVIATION...RCS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
334 PM CDT SUN JUN 22 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 334 PM CDT SUN JUN 22 2014
THE MAIN FOCUS THROUGH TOMORROW IS ON CONVECTIVE TRENDS AND
WHETHER ANY FLASH FLOODING IS STILL POSSIBLE.
AN MCV FROM OVERNIGHT HAS COME THROUGH MUCH OF THE REGION FROM
LATE THIS MORNING INTO THE EARLY AFTERNOON HOURS AND HAS KICKED UP
A BAND OF CONVECTION/RAIN OUT AHEAD OF IT. MUCH OF THE 22.12Z
GUIDANCE HAS NOT DONE A VERY GOOD JOB OF PICKING UP ON THIS
FEATURE AND STILL WANT TO DEVELOP A WIDE SWATH OF CONVECTION
ACROSS THE REGION THIS EVENING. THE HRRR HAS DONE A DECENT JOB OF
CAPTURING THIS CONVECTION AND CLEARS MOST OF THE REGION FROM THE
WEST EARLY THIS EVENING. THE MOST UNSTABLE AIR MASS APPEARS TO
STAY OUT AHEAD OF THE MCV...SO AM NOT EXPECTING MUCH IN THE WAY OF
SEVERE DEVELOPMENT BEHIND IT. CONFIDENCE IS NOT VERY HIGH WITH HOW
TONIGHT WILL PAN OUT WITH THE MAIN COLD FRONT STILL OFF TO THE
WEST...SO WILL KEEP THE FLASH FLOOD WATCH GOING FOR THE TIME
BEING AND LET THE EVENING PLAY OUT A BIT MORE BEFORE CANNING IT.
THE 22.12Z NAM/GFS/GEM DID TREND FASTER WITH PUSHING THE
PRECIPITATION/MID LEVEL TROUGH/SFC LOW OFF TO THE EAST TOMORROW
MORNING...SO HAVE TRENDED A BIT FASTER WITH ENDING THE RAIN
CHANCES TOMORROW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 334 PM CDT SUN JUN 22 2014
A BRIEF DRY PERIOD IS EXPECTED MONDAY NIGHT INTO TUESDAY MORNING
AS SUBSIDENT AIR COMES IN THE WAKE OF THE TROUGH. ANOTHER COLD
FRONT WILL DROP DOWN FROM CANADA TUESDAY AFTERNOON AND BRING THE
NEXT CHANCE OF RAIN ALONG WITH IT. SKINNY CAPE PROFILE WITH THIS
FEATURE WITH LESS THAN 1000 J/KG OF MLCAPE EXPECTED...SO NOT
THINKING THAT THIS WILL BE A SEVERE WEATHER PRODUCER AT THIS
POINT.
AFTER THAT FRONT DROPS TO THE SOUTH IT APPEARS TO STALL OUT FROM
THE HIGH PLAINS ON DOWN SOUTHEAST THROUGH THE MID MISSISSIPPI
RIVER VALLEY. CONFIDENCE NOT VERY HIGH WITH OUR PRECIPITATION
CHANCES TOWARD THE END OF THE WEEK...BUT ALSO DID NOT HAVE MUCH OF
A CHANCE TO DIG INTO THE DETAILS WITH CONVECTION ON GOING...SO
HAVE GONE WITH THE CONSENSUS OF THE MODEL BLENDS FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1243 PM CDT SUN JUN 22 2014
A LINE OF STRONG TO SEVERE THUNDERSTORMS WILL MOVE THROUGH KLSE
AROUND 22.1830Z. THE MAIN THREATS ARE DAMAGING WINDS AND LARGE
HAIL. ISOLATED TORNADOES ARE ALSO POSSIBLE. ADDITIONAL
THUNDERSTORMS ARE LIKELY TO DEVELOP IN THE WAKE OF THIS INITIAL
LINE THIS AFTERNOON AND EVENING AS A COLD FRONT APPROACHES THE
AREA. THESE THUNDERSTORMS WILL COME TO AN END AS THE COLD FRONT
PASSES THROUGH KRST AT 23.10Z AND KLSE AT 23.12Z. THE
THUNDERSTORMS MAY BRIEFLY PRODUCE IFR/MVFR CEILINGS AND
VISIBILITIES.
&&
.HYDROLOGY...
ISSUED AT 334 PM CDT SUN JUN 22 2014
HEAVY RAINFALL FROM LAST WEEK HAS PRIMED THE GROUND FOR ADDITIONAL
FLOODING WITH ANY STORMS THAT MAY MOVE THROUGH. THE STORMS TODAY
HAD SOME BRIEFLY INTENSE RAINFALL RATES AT ABOUT 2 INCHES PER HOUR
THOUGH THEY ONLY LASTED FOR ABOUT A HALF HOUR. MANY AREA RIVERS
ARE STILL ELEVATED FROM THE RECENT RAINFALL AND WILL LIKELY STAY
THAT WAY THROUGH THE WEEK. CONFIDENCE IS NOT VERY HIGH AT THIS
POINT ABOUT WHETHER THE FLASH FLOOD WATCH IS STILL NECESSARY FOR
TONIGHT...BUT WANT TO MAKE SURE THAT CONDITIONS WILL BE OKAY
BEFORE DROPPING IT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR WIZ017-029-
032>034-041-042-053>055-061.
MN...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR MNZ079-086>088-
094>096.
IA...FLASH FLOOD WATCH THROUGH MONDAY AFTERNOON FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...BOYNE
HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1211 PM CDT SUN JUN 22 2014
.UPDATE...VISIBILITIES CONTINUE TO IMPROVE IN THE EASTERN
COUNTIES...AS DAYTIME HEATING STARTS TO MIX THE BOUNDARY LAYER.
SHOULD SEE LOW STRATUS DECK IN THAT AREA CONTINUE TO MIX OUT AS
WELL BY EARLY THIS AFTERNOON. DIURNAL CUMULUS SHOULD DEVELOP IN
THE WAKE OF THE LOW STRATUS. HIGHS LOOK ON TRACK...RANGING FROM
THE 60S NEAR THE LAKE TO THE MID 80S WEST AND SOUTH OF MADISON.
OTHER ISSUE IS CONVECTIVE POTENTIAL THIS AFTERNOON WITH LINE OF
STORMS MOVING TOWARD THE AREA FROM SOUTHEAST MINNESOTA AND EASTERN
IOWA. THESE BEING DRIVEN BY CONVECTIVELY INDUCED VORTICITY MAXIMUM
ENTERING WESTERN IOWA. MEAN LAYER CAPES SHOULD INCREASE TO 1000 TO
1500 J/KG IN THE WESTERN PORTIONS OF THE AREA...AND COULD GET
SOMEWHAT HIGHER INTO THIS AFTERNOON.
DEEP LAYER SHEAR IS RELATIVELY WEAK...AROUND 20 KNOTS OR SO...SO
NOT SURE HOW WIDESPREAD ANY SEVERE WEATHER MAY BE IN OUR FAR
WESTERN COUNTIES. HRRR HAVING TROUBLE WITH CURRENT TRENDS...WITH
4 KM WRF/NMM KEEPING EVERYTHING JUST WEST OF THE AREA THIS
AFTERNOON.
SPC HAS FAR WEST IN SLIGHT RISK FOR SEVERE STORMS THIS
AFTERNOON...AND HAVE PUT THE FAR WESTERN THREE COUNTIES IN A
SEVERE THUNDERSTORM WATCH UNTIL 00Z MONDAY. WILL CERTAINLY HAVE
TO WATCH STORM TRENDS AS THEY SHIFT CLOSER TO THIS AREA...GIVEN
THE AMOUNT OF INSTABILITY AVAILABLE. WILL ADD PROGRESSIVELY HIGHER
POPS FOR THUNDER INTO THE WESTERN COUNTIES FOR THE AFTERNOON.
&&
.AVIATION/18Z TAFS/...VFR CONDITIONS WILL RETURN TO EASTERN TAF
SITES BY 18Z TO 19Z SUNDAY...AS LAST OF LOW STRATUS CLOUDS MIX
OUT. DIURNAL CUMULUS CLOUDS WILL DEVELOP DURING THE
AFTERNOON...WITH LIGHT WINDS. LINE OF THUNDERSTORMS IN SOUTHEAST
MINNESOTA AND EASTERN IOWA MAY AFFECT MADISON AFTER 21Z SUNDAY.
GIVEN UNCERTAINTY WITH HOW FAR EAST THESE STORMS MAY REACH...WILL
JUST MENTION VICINITY THUNDER IN MADISON BETWEEN 21Z SUNDAY AND
00Z MONDAY.
SHOULD SEE SOME LIGHT FOG AND POSSIBLY SOME LOW STRATUS CLOUDS
TONIGHT INTO EARLY MONDAY MORNING...DOWN TO NEAR ALTERNATE
MINIMUMS. NOT EXPECTING DENSE FOG AGAIN...AS WINDS ABOVE THE
SURFACE SHOULD BE STRONGER THAN LAST NIGHT.
LOW PRESSURE WILL MOVE NORTHEAST THROUGH THE REGION TONIGHT AND
MONDAY...WITH A COLD FRONTAL PASSAGE LATER MONDAY AFTERNOON OR
MONDAY EVENING. SHOWERS AND THUNDERSTORMS ARE EXPECTED MAINLY
AFTER 06Z MONDAY AND THROUGH THE DAY MONDAY. MVFR/IFR VISIBILITIES
ARE POSSIBLE IN ANY STORMS...WITH SOME GUSTY WINDS.
&&
.MARINE...DENSE FOG ADVISORY WILL CONTINUE FOR THE NEARSHORE
WATERS UNTIL AT LEAST 15Z MONDAY. WARM AND MOIST AIRMASS WILL
REMAIN OVER THE COOL LAKE WATERS DURING THIS TIME...AND WILL
REMAIN THERE UNTIL COLD FRONT MOVES THROUGH THE AREA MONDAY
EVENING. SO...MAY NEED TO EXTEND THE ADVISORY INTO MONDAY EVENING
IN LATER FORECASTS.
&&
.PREV DISCUSSION... /ISSUED 342 AM CDT SUN JUN 22 2014/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
MADE A RATHER SHARP DEVIATION FROM THE PREVIOUS FORECAST FOR THE
NEXT 24 HRS. THE MODELS HAVE SLOWED DOWN THE ARRIVAL OF THE NEXT
TROF...WITH SHORT WAVE RIDGING AND A DRY COLUMN NOW EXPECTED TO KEEP
THE AREA RAIN FREE THROUGH 06Z TONIGHT. IN THE VERY SHORT
TERM...CALM WINDS...DAMP GROUND...A VERY SATURATED BOUNDARY LAYER
AND SOME INFLUENCE FROM LAKE MICHIGAN HAS LEAD TO WIDESPREAD DENSE
FOG ACROSS THE SOUTHEAST. THE WESTERN EDGE IS TOUGH TO DETERMINE
BUT IS SOMEWHERE BETWEEN WATERTOWN AND MADISON. SOME BLOWOFF CIRRUS
FROM CONVECTION UPSTREAM IS HELPING TO KEEP SOUTH CENTRAL AREAS IN
BETTER SHAPE. THE SOUTHEAST IS ALSO UNDER THE INFLUENCE OF A COOLER
SOUTHEAST FLOW OFF THE LAKE. ALBEIT A VERY LIGHT FLOW...BUT IT/S
ENOUGH. A DENSE FOG ADVISORY IS IN EFFECT UNTIL 9 AM FOR ALL BUT THE
FAR WRN TIER OF COUNTIES. I MAY HAVE TO TRIM ANOTHER TIER OUT OF
THE ADVISORY EARLY IF MSN DOESN/T DETERIORATE SOON.
THE NEXT TROF BEGINS TO INFLUENCE THE AREA AFTER MIDNIGHT WITH SOME
DEEP Q-VECTOR CONVERGENCE IMPINGING ON THE AREA. THE LEADING WARM
ADVECTION IS UNIMPRESSIVE SO DON/T SEE MUCH NEED TO TRY TO BRING
THIS IN FASTER THAN THE BULK OF THE GUIDANCE SUGGESTS. CAPE LOOKS
WEAK WITH LOW LEVEL CAPPING. ANY THUNDER WILL BE ELEVATED AND NOT
VERY STRONG. WE COULD SEE SOME FOG AGAIN IN THE EAST AS THE FLOW
WILL BE ONSHORE AGAIN.
MONDAY AND MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
THE VERY SLOW-MOVING MID LEVEL SHORTWAVE WILL TRACK ACROSS WISCONSIN
ON MONDAY. VORTICITY ADVECTION...RIGHT ENTRANCE REGION OF THE UPPER
JET...STRONG 700MB OMEGA AND FRONTOGENESIS LINE UP OVER SOUTHERN WI
MIDDAY MONDAY. RAISED POPS TO CATEGORICAL FOR MUCH OF THE DAY.
EXPECTING SCATTERED THUNDERSTORMS GIVEN TALL SKINNY CAPE OF AROUND
1500 J/KG AND 20 KT BULK SHEAR AND THE FOCUSED SYNOPTIC FORCING.
PRECIPITABLE WATER VALUES OF AROUND 1.75 INCHES AND LOW MBE
VELOCITIES SHOW THE POTENTIAL FOR HEAVY RAIN OVER THE AREA.
RAIN WILL TAPER OFF FROM WEST TO EAST FROM LATE AFTERNOON THROUGH
EVENING. THE GFS IS SLOWER TO END THE PRECIP THAN THE NAM AND ECMWF.
LONG TERM...
TUESDAY...FORECAST CONFIDENCE MEDIUM.
EXPECTING QUIET WEATHER FOR MOST OF THE DAY TUESDAY WITH DRIER AIR
OVERHEAD AND LACK OF ANY FORCING. A SURFACE TO 850MB COLD FRONT
STATIONED ACROSS NORTHERN WI WILL DROP DOWN THROUGH SOUTHERN WI TUE
NIGHT. THERE IS A CHANCE OF SHOWERS AND MAYBE A THUNDERSTORM ALONG
THIS FRONT OVERNIGHT.
WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE LOW.
THE STALLED 925-850MB FRONT OVER SOUTHWEST WI WILL BE THE FOCUS FOR
POSSIBLE SHOWERS AND A FEW THUNDERSTORMS ON WEDNESDAY WITH A WEAK
SHORTWAVE ROLLING THROUGH. THEN THAT BOUNDARY MAY LIFT INTO NORTHERN
WI FOR THE REST OF THE WEEK AND KEEP SOUTHERN WI ON THE WARM AND
CAPPED SIDE OF THE FRONT PER THE 00Z ECMWF...OR IT COULD STALL RIGHT
OVER SOUTHERN WI AND CONTINUE TO BE THE FOCUS FOR ROUNDS OF SHOWERS
AND THUNDERSTORMS EACH DAY PER THE GFS. THEREFORE...THERE IS A
CHANCE FOR SHOWERS AND THUNDERSTORMS EVERY TIME PERIOD IN THE
EXTENDED FORECAST. TEMPERATURES WILL DEPEND ON THE PRECIP CHANCES.
WENT WITH CONSENSUS FORECAST VALUES.
THE ONE MORE CERTAIN THING IS THAT EASTERLY WINDS WILL PREVAIL
THROUGH THE EXTENDED AND KEEP LAKESHORE TEMPS COOLER.
AVIATION/12Z TAFS/...
LIFR CONDITIONS WILL CONTINUE ACROSS THE SOUTHEAST THROUGH ABOUT 14-
15Z WITH GRADUALLY IMPROVING CONDITIONS THEREAFTER. THE RAP AND
AMDAR AIRCRAFT SOUNDINGS INDICATE THIS STUFF IS 2-3KFT THICK. THIS
LOOKS VERY SIMILAR TO YESTERDAY. THE RAP HAS THIS MIXING OUT BY
AROUND NOON...GIVE OR TAKE...JUST LIKE YESTERDAY...SO SEE NO REASON
TO DISAGREE. THERE SHOULD ONLY BE SOME HIGH CLOUDS AROUND ONCE THE
LOW STUFF SCATTERS OUT. FOR THE AIR SHOW...HOWEVER...WE SHOULD
STILL SEE SOME LOWER CLOUDS AND FOG OVER THE WATER DUE TO THE MOIST
BOUNDARY LAYER AIR MOVING LITTLE OVER THE COLD WATERS OF THE LAKE.
IT/S POSSIBLE LAKE AREAS WILL CLEAR OUT...BUT CONFIDENCE IS LOW IN
THESE SITUATIONS. FOR KMSN...IMPROVEMENT WILL LIKELY OCCUR MUCH
QUICKER WITH VFR CONDITIONS LIKELY BY 14Z.
AN EASTERLY FLOW CONTINUING TONIGHT COULD BRING IN SOME LOWER VSBYS
AGAIN TO THE SOUTHEAST...BUT THERE WILL BE MUCH MORE FLOW ABOVE THE
DECOUPLED BOUNDARY LAYER SO NOT EXPECTING VSBYS TO BE AS LOW OR FOR
THERE TO BE MUCH IN THE WAY OF LOW STRATUS.
THUNDERSTORMS ARE POSSIBLE AT KMSN TOWARD 12Z MON AS A TROF
APPROACHES FROM THE WEST.
MARINE...
HAVE EXTENDED THE MARINE DENSE FOG ADVISORY AGAIN...THIS TIME TO 15Z
MON...OR 10 AM MON. JUST NOT SEEING MUCH PATTERN CHANGE OR REASON
FOR SIGGY IMPROVEMENT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...DENSE FOG ADVISORY UNTIL 10 AM CDT MONDAY FOR LMZ643>646.
&&
$$
UPDATE...WOOD
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
MONDAY THROUGH SATURDAY...MRC