Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/02/14
AREA FORECAST DISCUSSION
NWS PUEBLO CO
614 PM MDT MON SEP 1 2014
.UPDATE...
ISSUED AT 558 PM MDT MON SEP 1 2014
UPDATED TO PULL POPS ACROSS THE PLAINS THIS EVENING BASED ON
RADAR AND RECENT HI-RES MODEL DATA. MOISTURE AND LOW CLOUDS
MAY BE POSSIBLE OVER THE FAR SOUTHEAST PLAINS LATE TONIGHT INTO
TUESDAY MORNING...BUT NO PRECIP IS EXPECTED AT THIS TIME. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 240 PM MDT MON SEP 1 2014
MAIN NEAR/SHORT-TERM METEOROLOGICAL ISSUES ARE
TEMPERATURES...LOCALIZED GUSTY WINDS AT TIMES AND LOCALIZED LOW-
GRADE POPS.
CWFA EXPERIENCING NEAR SEASONAL SEPTEMBER AFTERNOON TEMPERATURES IN
COMBINATION WITH GENERALLY SUNNY SKIES...ALTHOUGH SOME VARIABLE
CLOUDS NOTED OVER PRIMARILY HIGHER TERRAIN LOCATIONS.
IN ADDITION...WIND GUSTS EXCEEDING 30 MPH AT TIMES HAVE BEEN
OBSERVED OVER THE MOUNTAINS OF CHAFFEE COUNTY. RECENT RADAR RETURNS
INDICATE SHOWERS AND THUNDERSTORMS NEARING FAR NORTHEASTERN
COLORADO...WELL NORTH OF OUR CWFA.
LATEST COMPUTER SIMULATIONS...REAL-TIME DATA AND FORECAST MODEL
SOUNDINGS INDICATE THAT GENERALLY DRY CONDITIONS SHOULD CONTINUE
OVER THE MAJORITY OF THE FORECAST DISTRICT FROM LATE THIS AFTERNOON
INTO TUESDAY AFTERNOON...ALTHOUGH RECENT HRRR MODEL DATA SUGGESTS
THAT SHOWERS AND THUNDERSTORMS MAY THREATEN PORTIONS OF NORTHERN EL
PASO AND KIOWA COUNTIES AS WELL AS SECTIONS OF LAS ANIMAS AND BACA
COUNTIES FROM LATER THIS AFTERNOON INTO THIS EVENING.
FOR TUESDAY...THE HIGHEST PROBABILITY OF ISOLATED SHOWER AND
THUNDERSTORM ACTIVITY SHOULD BE NOTED OVER WESTERN HIGHER TERRAIN
LOCATIONS...PRIMARILY DURING THE AFTERNOON AND EVENING HOURS.
GUSTY...PRIMARILY HIGHER TERRAIN WINDS ARE ALSO ANTICIPATED AT TIMES
FROM LATER THIS AFTERNOON INTO TUESDAY WHILE ABOVE SEASONAL EARLY
SEPTEMBER AFTERNOON TEMPERATURES ARE PROJECTED TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 240 PM MDT MON SEP 1 2014
...HOT WITH LOW THUNDERSTORM CHANCES THROUGH EARLY THURSDAY THEN
COOLER WITH INCREASING THUNDERSTORM CHANCES...
TUESDAY EVENING INTO EARLY THURSDAY...THE AIR MASS OVER THE REGION
WILL BE QUITE WARM AND THE THUNDERSTORM CHANCES WILL BE LOW. COULD
BE SOME SPOTTY DRY THUNDERSTORMS AROUND TUESDAY EVENING...MAINLY
OVER THE MOUNTAINS. THEN...WEDNESDAY AFTERNOON...COULD BE SOME
SPOTTY DRY LINE ACTIVITY ACROSS THE FAR SOUTHEAST PLAINS. MODELS
HAVE BEEN BACK AND FORTH ON THIS SO CONFIDENCE IS A LITTLE LOW BUT
THE POSSIBILITY REMAINS ALIVE.
ON THURSDAY...THINGS START TO TRANSITION TO A COOLER...WETTER
PATTERN. MODELS HAVE BEEN PRETTY CONSISTENT ON THIS SO CONFIDENCE
IS INCREASING. IT STARTS WITH THE ARRIVAL OF A COLD FRONT THROUGH
THE EASTERN PLAINS THURSDAY AFTERNOON. THE FRONT PUSHES INTO THE
REGION AS THE RESULT OF AN UPPER DISTURBANCE MOVING THROUGH THE
NORTHERN ROCKIES AND PLAINS. AS THE FRONT MOVES IN...MOIST UPSLOPE
WINDS BEHIND THE FRONT GRADUALLY FIRE THUNDERSTORMS OVER AND NEAR
THE MOUNTAINS IN THE AFTERNOON...SOME OF WHICH WORK EAST ACROSS THE
PLAINS BY LATE IN THE DAY. WITH ADDED MOISTURE IN THE AIR AND
UPSLOPE WINDS...THE THREAT FOR STRONG STORMS WILL INCREASE THIS DAY.
FRIDAY THROUGH MONDAY...WE COULD BE DEALING WITH SOME RICH
SUBTROPICAL MOISTURE AT TIMES...JUST DEPENDING ON HOW THINGS TRACK
OVER THE NEXT FEW DAYS. RIGHT NOW...INDICATIONS ARE THAT FRIDAY AND
SATURDAY COULD BOTH BE PRETTY WET OVER THE REGION WITH CONCERNS OF
FLASH FLOODING. SUNDAY AND MONDAY STILL LOOK PRETTY WET FOR THE
MOUNTAINS...BUT THE PLAINS LOOK MORE STABLE WITH LESS ACTIVITY. ALL
OF THIS IS STILL SEVERAL DAYS AWAY AND HIGHLY SUBJECT TO
CHANGE...HOWEVER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 240 PM MDT MON SEP 1 2014
VFR CONDITIONS ARE ANTICIPATED AT THE KALS...KCOS AND KPUB TAF SITES
THROUGH TUESDAY AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
SHORT TERM...77
LONG TERM...LW
AVIATION...LW
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
944 AM MDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 924 AM MDT SUN AUG 31 2014
WATER VAPOR IMAGERY SHOWING STRONG UPPER TROF AXIS MOVING THROUGH
SOUTHWEST WYOMING THIS MORNING. AHEAD OF THE TROF SCATTERED
SHOWERS AND A FEW THUNDERSTORMS CONTINUE TO MOVE EAST ACROSS
NORTHERN PORTIONS OF CWA AND ACROSS THE MOUNTAINS. LATEST RAP SHOWING
MODEST QG ASCENT OVER NORTHERN COLORADO WITH THE TROF AND THIS
WILL CONTINUE THROUGH THE AFTERNOON. INITIAL COLD FRONT HAS MOVED
THROUGH MUCH OF NORTHEAST COLORADO AS WINDS HAVE SHIFTED NORTHEAST
WHILE MAINTAINING DEWPOINTS IN THE UPPER 40S TO MID 50S.
MAIN CHANGE TO ZONES WAS TO INCREASE CHANCES OF
SHOWERS/STORMS THIS MORNING AND AFTERNOON OVER THE MOUNTAINS AND
FAR NORTHERN PLAINS. WOULD NOT BE SURPRISED TO SEE A FEW SEVERE
STORMS OVER THE NORTHEAST PLAINS GIVEN MODERATE ASCENT WITH JET
STREAK AND AMPLE LOW LEVEL MOISTURE. FORECAST SOUNDINGS INDICATE
1000-1500J/KG OF CAPE POSSIBLE ESPECIALLY OVER THE PLAINS. WINDS
TO 70 MPH AND SMALL HAIL WOULD BE THE MAIN THREAT GIVEN THE STRONG
MID LEVEL FLOW OF 50KT AT 500MB.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 205 AM MDT SUN AUG 31 2014
TROUGH AND COLD FRONT WILL MOVE ACROSS COLORADO TODAY. DECENT BAND
OF SHOWERS WITH A SHARP WIND SHIFT MOVING INTO THE NORTHERN
MOUNTAINS NOW...THIS SHOWER BAND HAS HAD 40 MPH WINDS WITH IT
ACROSS SOUTHERN WYOMING...PROBABLY NOT AS STRONG FURTHER SOUTH BUT
EXPECT SOME WEST TO SOUTHWEST WIND WITH IT AS IT MOVES ACROSS THIS
MORNING. THERE SHOULD BE ADDITIONAL SHOWER BANDS MUCH OF THE DAY
OVER THE MOUNTAINS...WHILE WEST WINDS WILL LIMIT PRECIPITATION
EAST OF THE FRONT RANGE THROUGH MIDDAY. WIND SHIFT TO A MORE
NORTHERLY DIRECTION AND THE TROUGH AXIS COME THIS AFTERNOON AND
THAT WOULD BE THE BEST CHANCE OF STORMS EAST OF THE MOUNTAINS. BY
SUNSET THE TROUGH SHOULD BE EAST OF THE STATE AND THE SHOWERS
SHOULD BE EXITING. CAPES WILL BE VERY LOW SO ONLY EXPECTING THE
WIND WITH THE SHOWERS OVER MOST OF THE AREA TODAY. GENERALLY
EXPECTING GUSTS IN THE 30-40 MPH RANGE THOUGH THERE IS POTENTIAL
FOR NEAR SEVERE GUSTS IN ORGANIZED LINES...NOT EXPECTING THAT MUCH
PRECIP THOUGH SO A LOW THREAT. NEAR THE EASTERN BORDER CONVECTION
MAY BE A BIT STRONGER WITH BETTER MOISTURE...AGAIN MAINLY A WIND
THREAT BUT MORE OF A CHANCE OUT THERE.
WITH THE CLOUD COVER AND SOME COLD ADVECTION THIS AFTERNOON HIGHS
WILL BE LOWER...CURRENT FORECAST LOOKS GOOD. I LOWERED TEMPS A
LITTLE TONIGHT WITH CLEARING...DRIER AIR...AND DIMINISHING WINDS
IN MOST AREAS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 205 AM MDT SUN AUG 31 2014
STRONG WEST-NORTHWESTERLY FLOW ALOFT IS PROGGED OVER THE CWA
MONDAY WITH THE UPPER TROUGH AXIS EAST OF COLORADO. THE JET LEVEL
FLOW DECREASES AND BECOMES ZONAL MONDAY NIGHT THROUGH TUESDAY
NIGHT. DOWNWARD SYNOPTIC SCALE ENERGY IS PROGGED OVER THE FORECAST
AREA ON MONDAY...WEAKER...BUT STILL DOWNWARD MONDAY NIGHT THROUGH
TUESDAY NIGHT. THE LOW LEVEL WINDS LOOK TO BE WEAK UPSLOPE MONDAY
INTO MONDAY EVENING...THEN NORMAL DIURNAL PATTERNS TAKE OVER. THE
PLAINS HAVE FAIRLY STRONG SOUTHERLY WINDS PROGGED ON TUESDAY.
MOISTURE IS NOT GREAT THROUGH THE PERIODS...BUT THERE IS SOME
PROGGED AT THE LOWER LEVELS OF THE PLAINS. THE PRECIPITABLE WATER
VALUES ARE GENERALLY FROM THE 0.30 TO 0.80 INCH RANGE THROUGHOUT.
THE BOUNDARY LAYER DEW POINT READINGS RANGE FROM THE 20S F WEST TO
LOWER 50S F EAST THROUGH THE PERIODS. THERE IS TINY BIT OF CAPE
PROGGED OVER THE PLAINS MONDAY AFTERNOON...WITH CONSIDERABLY MORE
PROGGED MAINLY FOR THE PLAINS ON TUESDAY AND TUESDAY EVENING.
CONCERNING MEASURABLE RAINFALL ON THE QPF FIELDS...THERE ARE TINY
AMOUNTS PROGGED HERE AND THERE NOW AND THEN FROM THE VARIOUS
MODELS MONDAY THROUGH TUESDAY NIGHT...BUT IT IS VERY
INSIGNIFICANT. FOR POPS...WILL GO WITH 0-10%S THROUGH THE PERIODS.
FOR TEMPERATURES...MONDAY`S HIGHS ARE 1-3 C COLDER THAN TODAY`S
EXPECTED READINGS. TUESDAY`S HIGHS ARE 2-5 C WARMER THAN MONDAY`S.
FOR THE LATER DAYS...WEDNESDAY THROUGH SATURDAY...THE MODELS HAVE
THE UPPER RIDGE CENTERED IMMEDIATELY SOUTH-SOUTHEAST OF COLORADO
ALL FOUR DAYS. THE FLOW ALOFT IS WEST-SOUTHWESTERLY ALL FOUR
DAYS. MOISTURE INCREASES A BIT THURSDAY INTO NEXT WEEKEND. MODELS
ALSO SHOW UPSLOPE EAST OF THE DIVIDE FROM LATER THURSDAY THROUGH
SATURDAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z MONDAY MORNING)
ISSUED AT 924 AM MDT SUN AUG 31 2014
STILL SOME UNCERTAINTY ON HOW MUCH CONVECTION WILL SURVIVE ACROSS
THE LOCAL TERMINALS AS UPPER TROF MOVES ACROSS THE REGION THIS
AFTERNOON. INITIALLY...WE HAVE SOME UPSLOPE FLOW AS LOW LEVEL
MOISTURE REMAINS HIGH. HOWEVER AS BANDS OF SHOWERS MOVE OFF THE
MOUNTAINS THERE WILL BE MORE DOWNSLOPE WINDS DEVELOPING FROM THE
NORTHWEST. THIS WILL DRY THINGS OUT WITH LESSER CHANCES OF
THUNDERSTORMS. WILL MAINTAIN TEMPO GROUPS FOR THE HIGHER WINDS AS
THE MAIN THREAT. RAPID CLEARING BEHIND THE TROF EARLY THIS EVENING
WITH CLEARING SKIES.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ENTREKIN
SHORT TERM...GIMMESTAD
LONG TERM...RJK
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS ALBANY NY
224 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING SHOWERS AND
THUNDERSTORMS TODAY...SOME POSSIBLY WITH HEAVY RAINFALL. WEAK HIGH
PRESSURE WILL BUILD IN LABOR DAY. IT WILL BE VERY WARM AND HUMID AND
MAINLY RAIN-FREE...BUT AN ADDITIONAL THUNDERSTORM CANNOT BE RULED
OUT. ANOTHER COLD FRONT IS EXPECTED TO BRING A CHANCE FOR SHOWERS
AND THUNDERSTORMS TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM EDT...RADAR INDICATED THAT SHOWERS AND THUNDERSTORMS
WERE STILL HAVING A DIFFICULT TIME MAKING INTO HERKIMER COUNTY...AS
THEY WERE MAINLY TRACKING TO THE NORTHWEST OF NORTHERN HERKIMER
COUNTY...ALONG THE TUG HILL PLATEAU.
BOTH THE LATEST RUC13 AND HRRR NOW KEEP MOST OF THE ACTIVITY
CONFINED TO OUR NORTHWEST AREAS OVERNIGHT SO WE DECIDED TO TRIM BACK
THE POPS EVEN MORE COMPARED TO THE LAST UPDATE.
THE IFR 11U-3.9U IFR SATELLITE PICTURES INDICATED STRATUS SLOWLY
OVERSPREADING THE REGION FROM THE SOUTH...WHILE MID AND HIGH CLOUDS
WERE WORKING IN FROM THE WEST.
TEMPERATURES WERE STILL MILD...GENERALLY IN THE 60S THANKS TO THE
INCREASING CLOUDS AND A PERSISTENT SOUTHERLY BREEZE.
FOR THE REST OF THE OVERNIGHT...LOOK FOR SCATTERED SHOWERS AND
PERHAPS A RUMBLE OF THUNDER (THE SHOWALTER INDICES WERE GENERALLY
JUST ABOVE 0 SO MUCH INSTABILITY)...OVER MAINLY OUR PORTION OF THE
ADIRONDACK PARK. EVERYONE ELSE SHOULD REMAIN DRY WITH INCREASING
CLOUDS.
NO CHANGES TO OVERNIGHT LOWS...LOOK FOR THEM TO ONLY DROP A POINT OR
TWO MORE...GENERALLY STAYING IN THE 60S ALL NIGHT ALONG. THE
SOUTHERLY BREEZE WILL PERSIST 5 TO 15 MPH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
STILL SOME QUESTION AS TO HOW MUCH CLOUD COVER WILL BE OVER THE
REGION TOMORROW. SOUTHWEST BOUNDARY LAYER FLOW AND A LOOSENING
BOUNDARY LAYER THERMAL GRADIENT SHOULD PROMOTE SOME BREAKS IN
CLOUD COVER. THERE SHOULD ALSO BE BREAKS IN THE LEFTOVER
CONVECTIVE DEBRIS FROM CONVECTION IN THE GREAT LAKES AND WESTERN
NY/PA. CLOUD COVER CURRENTLY UPSTREAM IN THE OH VALLEY AND GREAT
LAKES IS SCATTERED TO BROKEN. SO WITH THE PROSPECTS FOR AT LEAST
SOME INTERVALS OF SUN...WITH RAPIDLY WARMING BOUNDARY LAYER
TEMPERATURES...HIGHS SOLIDLY IN THE 80S SUNDAY...BUT UPPER 70S
SOUTHERN ADIRONDACKS WHERE SHOWERS AND THUNDERSTORMS SHOULD AFFECT
EARLIER IN THE DAY.
UPPER DYNAMICS...ALONG WITH A LITTLE LOW LEVEL JET SEGMENT TRACKS
THROUGH THE REGION SUNDAY AND SUNDAY NIGHT. DEEP MOISTURE SEEN IN
THE SATELLITE DERIVED SOUNDER IMAGERY OF PWAT...IS SURGING NORTH
FROM THE MS/TN VALLEY. SO...COVERAGE OF SHOWERS AND SCATTERED
THUNDERSTORMS SHOULD INCREASE TO LIKELY IN THE AFTERNOON IN MOST
AREAS. LOCALLY HEAVY RAIN IS POSSIBLE AND WILL ADDRESS IN
HAZARDOUS WEATHER OUTLOOK...BUT NO WIDESPREAD OR HIGH IMPACT FLOOD
THREAT EXPECTED.
WEAK COLD FRONT EXITS SUNDAY NIGHT WITH JUST SOME LINGERING
SCATTERED SHOWERS AND THUNDERSTORMS...WITH THE BEST COVERAGE IN
THE MID HUDSON VALLEY...BERKSHIRES AND NW CT SUNDAY EVENING. SOME
QUESTION AS TO HOW FAR SOUTH THE WEAK LOW LEVEL BOUNDARY GETS...SO
SCATTERED SHOWERS AND THUNDERSTORMS COULD LINGER THROUGH MUCH OF
MONDAY IN THE MID HUDSON VALLEY AND NW CT...BUT JUST SCATTERED...
WITH ISOLATED AFTERNOON ACTIVITY ELSEWHERE. STILL...SOME PERIODS
OF SUNSHINE EXPECTED MONDAY...WITH PERHAPS MORE CLOUDS THAN SUN IN
THE MID HUDSON VALLEY AND NW CT. HIGHS MONDAY SOLIDLY IN THE 80S.
THERE COULD BE A LULL IN THE SHOWER AND THUNDERSTORM ACTIVITY
MONDAY NIGHT WITH PARTIAL CLEARING...BUT DEW POINTS ARE NOT
EXPECTED TO DROP MUCH IF ANY...SO LOWS MONDAY NIGHT IN THE 60S.
ANOTHER COLD FRONT APPROACHES TUESDAY...WITH A BIT BETTER BOUNDARY
LAYER FRONTOGENESIS AND THERMAL GRADIENT TRACKING TOWARD THE
REGION. CURRENT CONSENSUS ON TIMING SUGGESTS SOME SUNSHINE AND
DAYTIME HEATING AT LEAST TUESDAY MORNING...WITH THE LEADING EDGE
OF SCATTERED SHOWERS AND THUNDERSTORMS APPROACHING WESTERN AREAS
MIDDAY OR EARLY AFTERNOON TUESDAY...THEN AFFECTING THE REST OF THE
REGION THROUGH THE AFTERNOON. HIGHS TUESDAY SOLIDLY IN THE 80S.
THUNDERSTORMS TUESDAY COULD BE STRONG BASED ON THE POTENTIAL
INSTABILITY...THERMAL GRADIENT FORCING AND BOUNDARY LAYER WINDS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MIDWEEK THROUGH THE END OF THE WORK WEEK WILL FEATURE DRY CONDITIONS
AS HIGH PRESSURE MOVES OVER THE FORECAST AREA BEHIND A COLD FRONT.
HOWEVER...A COLD FRONT ON SATURDAY WILL BRING A SHOWERY START FOR
THE BEGINNING OF THE WEEKEND.
TEMPERATURES WILL AVERAGE A FEW DEGREES ABOVE NORMAL...WITH HIGHS
FROM AROUND 70 DEGREES...TO THE LOWER AND MID 80S WEDNESDAY THROUGH
FRIDAY. SATURDAY WILL BE COOLER WITH HIGHS FROM THE MID 60S TO
AROUND 809 DEGREES.
NIGHTTIME LOWS WILL BE IN THE MID 50S TO UPPER 60S RANGE JUST PRIOR
TO THE COLD FRONT TUESDAY NIGHT. WEDNESDAY NIGHT LOWS WILL RANGE
FROM AROUND 50 DEGREES IN THE WESTERN ADIRONDACKS...TO NEAR 60
DEGREES DOWN THE HUDSON VALLEY. THEN READINGS SLOWLY BOUNCE BACK...
WITH LOWS FROM MAINLY THE LOWER AND MID 50S IN THE MOUNTAINS...TO
THE LOWER 60S DOWN THE HUDSON VALLEY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 200 AM...CIGS AT THE KGFL/KALB/KPOU TAF SITES ARE VERY CLOSE
TO THE MVFR/VFR CUTOFF OF 3000 FEET...WITH KALB STILL ONLY SCT AT
3300 FEET. AT KPSF CIGS ARE AROUND 1500 FEET. EXPECT MAINLY MVFR
CIGS AT ALL THE TAF SITES THROUGH AROUND 15Z...WITH OCCASIONAL IFR
CIGS AT KPSF. AFTER 15Z CIGS SHOULD RISE TO MAINLY VFR AT
KGFL/KALB/KPOU...AND MVFR AT KPSF. VCSH HAS BEEN INCLUDED AT ALL THE
TAF SITES AFTER 15Z. THE MAIN BAND OF MOISTURE ASSOCIATED WITH THE
FRONTAL BOUNDARY AND UPPER LEVEL TROF WILL MOVE ACROSS THE TAF SITES
LATER SUNDAY AFTERNOON AND EVENING. HAVE FORECAST MVFR CIGS/VSBYS AT
ALL THE TAFS SITES AFTER 19Z/20Z AS WIDESPREAD SHOWERS MOVE
IN...WITH A PROB 30 GROUP GENERALLY BETWEEN 19Z AND 01Z FOR A CHANCE
OF TSTMS WITH MVFR CONDITIONS. THE WIDESPREAD SHOWERS WILL LIKELY
END BY AROUND 01Z/02Z AT THE TAF SITES...BUT EXPECT MVFR CIGS/VSBYS
TO LINGER DUE TO FOG AND STRATUS STILL OVER THE REGION.
WINDS WILL BE CALM OR SOUTH AT 8 KTS OR LESS THROUGH THE REST OF
TONIGHT...THEN SOUTH OR SOUTHWEST AT 7 TO 10 KTS ON SUNDAY AND
SUNDAY EVENING...BECOMING 5 KTS OR LESS AFTER 02Z SUNDAY NIGHT.
OUTLOOK...
LATE SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED
SHRA...TSRA.
LABOR DAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA.
MONDAY NIGHT: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
LATE TONIGHT INTO SUNDAY A SLOW MOVING COLD FRONT WILL BRING A
ROUND OF SHOWERS AND THUNDERSTORMS...SOME POSSIBLY WITH HEAVY
RAINFALL. WEAK HIGH PRESSURE WILL BUILD IN LABOR DAY. IT WILL BE
VERY WARM HUMID AND MAINLY RAIN-FREE...BUT AN ADDITIONAL
THUNDERSTORM CANNOT BE RULED OUT. ANOTHER COLD FRONT IS
EXPECTED TO BRING A CHANCE FOR SHOWERS AND THUNDERSTORMS TUESDAY
AND TUESDAY NIGHT.
MINIMUM RH VALUES SHOULD BE BETWEEN 65 TO 75 PERCENT SUNDAY ASS
COVERAGE OF SHOWERS AND THUNDERSTORMS INCREASES. MINIMUM RH VALUES
MONDAY SHOULD BE 55 TO 65 PERCENT. MAXIMUM RH VALUES TONIGHT AND
TOMORROW NIGHT ARE EXPECTED TO BE 80 TO 100 PERCENT WITH SOME DEW
FORMATION.
THE SURFACE WIND BE SOUTH TO SOUTHWEST AT 15 MPH OR LESS TONIGHT
THROUGH SUNDAY NIGHT...THEN BECOME WEST TO SOUTHWEST MONDAY.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS WILL DEVELOP LATE TONIGHT AND
ESPECIALLY SUNDAY INTO SUNDAY EVENING. AVERAGE BASIN RAINFALLS
LOOK TO GENERALLY BE UNDER AN INCH SO AT THIS POINT...MAIN STREAM
RIVERS WILL GENERALLY SEE LITTLE OR NO RISES.
HOWEVER...WITH PWAT VALUES FORECAST TO INCREASE TO 2 INCHES...ANY
THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL EASILY EXCEEDING
AN INCH. ANY TRAINING THUNDERSTORMS COULD RESULT LOCALIZED PONDING
OF WATER IN AREAS OF POOR DRAINAGE.
ADDITIONAL THUNDERSTORMS ON LABOR DAY LOOK ISOLATED AND GENERALLY
NOT EXPECTED TO PRODUCE ADDITIONAL HYDRO PROBLEMS.
MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE LATE TUESDAY INTO
WEDNESDAY AS A STRONGER COLD FRONT ARRIVES.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SND/HWJIV/NAS
NEAR TERM...HWJIV
SHORT TERM...NAS
LONG TERM...ELH
AVIATION...GJM
FIRE WEATHER...NAS
HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1243 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING SHOWERS AND
THUNDERSTORMS TODAY...SOME POSSIBLY WITH HEAVY RAINFALL. WEAK HIGH
PRESSURE WILL BUILD IN LABOR DAY. IT WILL BE VERY WARM AND HUMID AND
MAINLY RAIN-FREE...BUT AN ADDITIONAL THUNDERSTORM CANNOT BE RULED
OUT. ANOTHER COLD FRONT IS EXPECTED TO BRING A CHANCE FOR SHOWERS
AND THUNDERSTORMS TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM EDT...RADAR INDICATED THAT SHOWERS AND THUNDERSTORMS
WERE STILL HAVING A DIFFICULT TIME MAKING INTO HERKIMER COUNTY...AS
THEY WERE MAINLY TRACKING TO THE NORTHWEST OF NORTHERN HERKIMER
COUNTY...ALONG THE TUG HILL PLATEAU.
BOTH THE LATEST RUC13 AND HRRR NOW KEEP MOST OF THE ACTIVITY
CONFINED TO OUR NORTHWEST AREAS OVERNIGHT SO WE DECIDED TO TRIM BACK
THE POPS EVEN MORE COMPARED TO THE LAST UPDATE.
THE IFR 11U-3.9U IFR SATELLITE PICTURES INDICATED STRATUS SLOWLY
OVERSPREADING THE REGION FROM THE SOUTH...WHILE MID AND HIGH CLOUDS
WERE WORKING IN FROM THE WEST.
TEMPERATURES WERE STILL MILD...GENERALLY IN THE 60S THANKS TO THE
INCREASING CLOUDS AND A PERSISTENT SOUTHERLY BREEZE.
FOR THE REST OF THE OVERNIGHT...LOOK FOR SCATTERED SHOWERS AND
PERHAPS A RUMBLE OF THUNDER (THE SHOWALTER INDICES WERE GENERALLY
JUST ABOVE 0 SO MUCH INSTABILITY)...OVER MAINLY OUR PORTION OF THE
ADIRONDACK PARK. EVERYONE ELSE SHOULD REMAIN DRY WITH INCREASING
CLOUDS.
NO CHANGES TO OVERNIGHT LOWS...LOOK FOR THEM TO ONLY DROP A POINT OR
TWO MORE...GENERALLY STAYING IN THE 60S ALL NIGHT ALONG. THE
SOUTHERLY BREEZE WILL PERSIST 5 TO 15 MPH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
STILL SOME QUESTION AS TO HOW MUCH CLOUD COVER WILL BE OVER THE
REGION TOMORROW. SOUTHWEST BOUNDARY LAYER FLOW AND A LOOSENING
BOUNDARY LAYER THERMAL GRADIENT SHOULD PROMOTE SOME BREAKS IN
CLOUD COVER. THERE SHOULD ALSO BE BREAKS IN THE LEFTOVER
CONVECTIVE DEBRIS FROM CONVECTION IN THE GREAT LAKES AND WESTERN
NY/PA. CLOUD COVER CURRENTLY UPSTREAM IN THE OH VALLEY AND GREAT
LAKES IS SCATTERED TO BROKEN. SO WITH THE PROSPECTS FOR AT LEAST
SOME INTERVALS OF SUN...WITH RAPIDLY WARMING BOUNDARY LAYER
TEMPERATURES...HIGHS SOLIDLY IN THE 80S SUNDAY...BUT UPPER 70S
SOUTHERN ADIRONDACKS WHERE SHOWERS AND THUNDERSTORMS SHOULD AFFECT
EARLIER IN THE DAY.
UPPER DYNAMICS...ALONG WITH A LITTLE LOW LEVEL JET SEGMENT TRACKS
THROUGH THE REGION SUNDAY AND SUNDAY NIGHT. DEEP MOISTURE SEEN IN
THE SATELLITE DERIVED SOUNDER IMAGERY OF PWAT...IS SURGING NORTH
FROM THE MS/TN VALLEY. SO...COVERAGE OF SHOWERS AND SCATTERED
THUNDERSTORMS SHOULD INCREASE TO LIKELY IN THE AFTERNOON IN MOST
AREAS. LOCALLY HEAVY RAIN IS POSSIBLE AND WILL ADDRESS IN
HAZARDOUS WEATHER OUTLOOK...BUT NO WIDESPREAD OR HIGH IMPACT FLOOD
THREAT EXPECTED.
WEAK COLD FRONT EXITS SUNDAY NIGHT WITH JUST SOME LINGERING
SCATTERED SHOWERS AND THUNDERSTORMS...WITH THE BEST COVERAGE IN
THE MID HUDSON VALLEY...BERKSHIRES AND NW CT SUNDAY EVENING. SOME
QUESTION AS TO HOW FAR SOUTH THE WEAK LOW LEVEL BOUNDARY GETS...SO
SCATTERED SHOWERS AND THUNDERSTORMS COULD LINGER THROUGH MUCH OF
MONDAY IN THE MID HUDSON VALLEY AND NW CT...BUT JUST SCATTERED...
WITH ISOLATED AFTERNOON ACTIVITY ELSEWHERE. STILL...SOME PERIODS
OF SUNSHINE EXPECTED MONDAY...WITH PERHAPS MORE CLOUDS THAN SUN IN
THE MID HUDSON VALLEY AND NW CT. HIGHS MONDAY SOLIDLY IN THE 80S.
THERE COULD BE A LULL IN THE SHOWER AND THUNDERSTORM ACTIVITY
MONDAY NIGHT WITH PARTIAL CLEARING...BUT DEW POINTS ARE NOT
EXPECTED TO DROP MUCH IF ANY...SO LOWS MONDAY NIGHT IN THE 60S.
ANOTHER COLD FRONT APPROACHES TUESDAY...WITH A BIT BETTER BOUNDARY
LAYER FRONTOGENESIS AND THERMAL GRADIENT TRACKING TOWARD THE
REGION. CURRENT CONSENSUS ON TIMING SUGGESTS SOME SUNSHINE AND
DAYTIME HEATING AT LEAST TUESDAY MORNING...WITH THE LEADING EDGE
OF SCATTERED SHOWERS AND THUNDERSTORMS APPROACHING WESTERN AREAS
MIDDAY OR EARLY AFTERNOON TUESDAY...THEN AFFECTING THE REST OF THE
REGION THROUGH THE AFTERNOON. HIGHS TUESDAY SOLIDLY IN THE 80S.
THUNDERSTORMS TUESDAY COULD BE STRONG BASED ON THE POTENTIAL
INSTABILITY...THERMAL GRADIENT FORCING AND BOUNDARY LAYER WINDS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MIDWEEK THROUGH THE END OF THE WORK WEEK WILL FEATURE DRY CONDITIONS
AS HIGH PRESSURE MOVES OVER THE FORECAST AREA BEHIND A COLD FRONT.
HOWEVER...A COLD FRONT ON SATURDAY WILL BRING A SHOWERY START FOR
THE BEGINNING OF THE WEEKEND.
TEMPERATURES WILL AVERAGE A FEW DEGREES ABOVE NORMAL...WITH HIGHS
FROM AROUND 70 DEGREES...TO THE LOWER AND MID 80S WEDNESDAY THROUGH
FRIDAY. SATURDAY WILL BE COOLER WITH HIGHS FROM THE MID 60S TO
AROUND 809 DEGREES.
NIGHTTIME LOWS WILL BE IN THE MID 50S TO UPPER 60S RANGE JUST PRIOR
TO THE COLD FRONT TUESDAY NIGHT. WEDNESDAY NIGHT LOWS WILL RANGE
FROM AROUND 50 DEGREES IN THE WESTERN ADIRONDACKS...TO NEAR 60
DEGREES DOWN THE HUDSON VALLEY. THEN READINGS SLOWLY BOUNCE BACK...
WITH LOWS FROM MAINLY THE LOWER AND MID 50S IN THE MOUNTAINS...TO
THE LOWER 60S DOWN THE HUDSON VALLEY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS PREVAILING ACROSS THE TERMINALS THIS
AFTERNOON...HOWEVER AN EXPANSIVE AREA OF STRATUS CLOUDS IS
NOTICEABLY CREEPING TOWARDS THE AREA FROM PA/NJ INTO THE CATSKILLS
OF NY...COURTESY OF LOW LEVEL MOISTURE INCREASING WITH A SOUTH TO
SOUTHWEST FLOW. FOR NOW...MOST OF THE CIGS ARE IN VFR RANGE
ALTHOUGH MVFR CIGS HAVE BEEN NOTED ACROSS SOME HIGHER TERRAIN
AREAS. WILL MENTION SCT CLOUDS EARLY WITH CIGS DEVELOPING LATER
THIS AFTERNOON OR EARLY EVENING...FROM SOUTHWEST TO NORTHEAST
ACROSS THE AREA. CIGS EXPECTED TO LOWER TO MVFR RANGE THIS
EVENING...ESPECIALLY LATER THIS EVENING AS LOW LEVEL DEWPOINTS
CONTINUE TO RISE. OVERNIGHT MAINLY MVFR CONDITIONS EXPECTED WITH
OVC CIGS AND SOME MIST. HOWEVER...THERE IS A CHANCE OF SOME
OCCASIONAL IFR AT KPSF BUT CONFIDENCE NOT GREAT ENOUGH TO MENTION
IN TAF AT THIS TIME.
CIGS WILL ONLY SLOWLY RISE ON SUNDAY...BUT SHOULD STILL GENERALLY
REMAIN IN MVFR RANGE THROUGH 18Z SUNDAY UNTIL LATER IN THE DAY. A
COLD FRONT WILL APPROACH FROM THE WEST BRINGING A THREAT OF MAINLY
AFTERNOON RAIN SHOWERS/THUNDERSTORMS. WILL MENTION VCSH IN KGFL/KALB
TAF PRIOR TO 18Z.
WINDS WILL BE SOUTHERLY AROUND 6-12 KT WITH SOME OCCASIONAL HIGHER
GUSTS. WIND SPEEDS WILL DECREASE TO AROUND 3-8 KT AFTER DARK.
WINDS WILL GENERALLY BE SOUTH-SOUTHWEST AROUND 5-10 KT ON SUNDAY.
OUTLOOK...
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
LABOR DAY: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA.
MONDAY NIGHT: LOW OPERATIONAL IMPACT. ISOLATED SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA...TSRA.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
LATE TONIGHT INTO SUNDAY A SLOW MOVING COLD FRONT WILL BRING A
ROUND OF SHOWERS AND THUNDERSTORMS...SOME POSSIBLY WITH HEAVY
RAINFALL. WEAK HIGH PRESSURE WILL BUILD IN LABOR DAY. IT WILL BE
VERY WARM HUMID AND MAINLY RAIN-FREE...BUT AN ADDITIONAL
THUNDERSTORM CANNOT BE RULED OUT. ANOTHER COLD FRONT IS
EXPECTED TO BRING A CHANCE FOR SHOWERS AND THUNDERSTORMS TUESDAY
AND TUESDAY NIGHT.
MINIMUM RH VALUES SHOULD BE BETWEEN 65 TO 75 PERCENT SUNDAY ASS
COVERAGE OF SHOWERS AND THUNDERSTORMS INCREASES. MINIMUM RH VALUES
MONDAY SHOULD BE 55 TO 65 PERCENT. MAXIMUM RH VALUES TONIGHT AND
TOMORROW NIGHT ARE EXPECTED TO BE 80 TO 100 PERCENT WITH SOME DEW
FORMATION.
THE SURFACE WIND BE SOUTH TO SOUTHWEST AT 15 MPH OR LESS TONIGHT
THROUGH SUNDAY NIGHT...THEN BECOME WEST TO SOUTHWEST MONDAY.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS WILL DEVELOP LATE TONIGHT AND
ESPECIALLY SUNDAY INTO SUNDAY EVENING. AVERAGE BASIN RAINFALLS
LOOK TO GENERALLY BE UNDER AN INCH SO AT THIS POINT...MAIN STREAM
RIVERS WILL GENERALLY SEE LITTLE OR NO RISES.
HOWEVER...WITH PWAT VALUES FORECAST TO INCREASE TO 2 INCHES...ANY
THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL EASILY EXCEEDING
AN INCH. ANY TRAINING THUNDERSTORMS COULD RESULT LOCALIZED PONDING
OF WATER IN AREAS OF POOR DRAINAGE.
ADDITIONAL THUNDERSTORMS ON LABOR DAY LOOK ISOLATED AND GENERALLY
NOT EXPECTED TO PRODUCE ADDITIONAL HYDRO PROBLEMS.
MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE LATE TUESDAY INTO
WEDNESDAY AS A STRONGER COLD FRONT ARRIVES.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SND/HWJIV/NAS
NEAR TERM...HWJIV
SHORT TERM...NAS
LONG TERM...ELH
AVIATION...JPV
FIRE WEATHER...NAS
HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
607 AM EDT SUN AUG 31 2014
.SYNOPSIS...
HIGH PRESSURE WELL OFF THE EAST COAST WILL MAINTAIN A SOUTHWESTERLY
FLOW OVER THE AREA THROUGH THE FIRST PART OF THE WEEK. A WEAK COLD
FRONT IS THEN EXPECTED TO MOVE ACROSS OUR AREA TUESDAY NIGHT AND
EARLY WEDNESDAY. HIGH PRESSURE WILL BUILD IN BEHIND THIS FRONT FOR
THE SECOND HALF OF THE WEEK. ANOTHER COLD FRONT MAY APPROACH FROM
THE WEST NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
OUR REGION WILL MAINLY BE CAUGHT BETWEEN SYSTEMS TODAY, AS AN
UPPER-LEVEL RIDGE REMAINS SITUATED TO OUR SOUTH AND SOUTHEAST WITH
SURFACE HIGH PRESSURE TO THE EAST. MEANWHILE, AN UPPER-LEVEL TROUGH
WILL CONTINUE TO TRACK ACROSS THE GREAT LAKES THEN ACROSS SOUTHERN
ONTARIO CANADA. THIS WILL RESULT IN A DEEP SOUTHWESTERLY FLOW, WHICH
WILL PULL AN ABUNDANCE OF MOISTURE INTO OUR REGION. AS A RESULT, A
MORE HUMID DAY IS EXPECTED.
THE PRESENCE OF SOME WAA COMBINED WITH THETA-E ADVECTION IS HELPING
TO PRODUCE A DECENT AMOUNT OF CLOUD COVER. THERE MAY BE SOME BREAKS
IN THIS AS THE FLOW ABOVE THE SURFACE INCREASES SOME, HOWEVER IT
WILL ALSO BE FIGHTING AN INVERSION. THE INITIAL WAA AND INCREASE
IN MOISTURE MAY BE ENOUGH TO RESULT IN SOME ISENTROPIC LIFT TO POP
A FEW SHOWERS THIS MORNING MAINLY ACROSS OUR WESTERN TO NORTHERN
ZONES. THIS SCENARIO WAS LESS CERTAIN AS SOME MODEL GUIDANCE THAT
HINTED AT THIS SEEM TO HAVE LOST A SUBTLE SHORT WAVE RUNNING OUT
AHEAD OF THE MAIN FEATURE. THE HRRR HAD THE RIGHT IDEA, BUT SO FAR
IT IS OVERDONE WITH THE COVERAGE. THERE WAS HOWEVER A SMALL GROUP
OF SHOWERS THAT DEVELOPED IN THE LEHIGH VALLEY BUT THEN DISSIPATED
AS IT MOVED NORTHEASTWARD. ANOTHER ISOLATED SHOWER CANNOT BE RULED
OUT EARLY, BUT OTHERWISE THE MAIN POPS WERE DELAYED SOME AND THEN
WERE GRADUALLY EXPANDED AND INCREASED EASTWARD WITH TIME.
AS WE STEP FORWARD THROUGH THE DAY, ENOUGH HEATING COMBINED WITH
CLIMBING SURFACE DEW POINTS SHOULD RESULT IN ENOUGH INSTABILITY
/MLCAPE UP TO 1500 J/KG/ TO PRODUCE SHOWERS AND THUNDERSTORMS. THE
BULK OF THIS ACTIVITY IS EXPECTED TO DEVELOP TO OUR WEST NEAR A WEAK
FRONTAL BOUNDARY WITH ADDITIONAL DEVELOPMENT POSSIBLY NEAR A
DIFFERENTIAL HEATING ZONE. THE HEIGHT FALLS ARE WEAK THIS FAR EAST
AS THE SHORT WAVE TROUGH TRACKS TO OUR NORTH LATE IN THE DAY.
HOWEVER, AN INCREASE IN THE MID LEVEL FLOW TO NEAR 40 KNOTS WILL
INCREASE THE SHEAR WITH TIME. THIS SHOULD BE ENOUGH TO PROMOTE SOME
STORM ORGANIZATION WITH THE MAIN MODE BEING LINE SEGMENTS. IN
ADDITION, THE PW VALUES ARE FORECAST TO INCREASE TO AROUND 2 INCHES
WHICH WILL LEAD TO DOWNPOURS. THESE DOWNPOURS MAY RESULT IN BRIEF
POOR DRAINAGE FLOODING, HOWEVER THE FLASH FLOOD THREAT GENERALLY
LOOKS LOW AS THERE SHOULD BE ENOUGH OF A STORM MOTION.
THE MOIST ENVIRONMENT COMBINED WITH ENOUGH INSTABILITY COULD ALSO
RESULT IN SOME STORMS PRODUCING FREQUENT LIGHTNING. GIVEN THE
FORECAST THERMODYNAMIC SETUP, SOME STORMS WILL BE CAPABLE OF
PRODUCING GUSTY TO PERHAPS LOCALLY DAMAGING WINDS. THIS GENERALLY
LOOKS TO BE FROM ABOUT THE INTERSTATE 95 CORRIDOR ON NORTH AND WEST
BY LATE AFTERNOON. WE THEREFORE MAINTAINED INCREASING POPS FROM WEST
TO EAST WITH THE WESTERN ZONES GOING TO LIKELY IN THE AFTERNOON, AND
WE ALSO ADDED SOME ENHANCED WORDING. MUCH OF THE EASTERN AND
SOUTHEASTERN ZONES MAY REMAIN DRY FOR THE BULK OF THE DAY.
AS FOR HIGH TEMPERATURES, WE USED AN EVEN BLEND OF THE NAM/GFS MOS
THEN ADJUSTED DOWN A LITTLE BIT FOR SOME AREAS WITH THE IDEA OF LOTS
OF CLOUDS PREVAILING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
THE AFOREMENTIONED SHORT WAVE TROUGH IS FORECAST TO DAMPEN OUT AS IT
TRACKS WELL TO OUR NORTH TONIGHT. THERE IS STILL A TRAIL OF SHORT
WAVES ROLLING UP THE BACKSIDE OF THE UPPER-LEVEL RIDGE WITH ALSO A
WEAKENING FRONTAL BOUNDARY NEARING THE AREA. THE FORECAST SOUNDINGS
INDICATE THAT ENOUGH INSTABILITY IS MAINTAINED FOR AWHILE FOR SOME
SHOWERS AND THUNDERSTORMS TO CONTINUE THROUGH THE EVENING,
ESPECIALLY FROM THE INTERSTATE 95 CORRIDOR ON NORTH AND WEST. A
SOMEWHAT MORE PRONOUNCED SHORT WAVE MAY HELP TO FOCUS A CONVECTIVE
CLUSTER OVERNIGHT, HOWEVER WHERE THIS IS FOCUSED HAS LESS CERTAINTY
WITH IT ATTM. AS THE PW VALUES REMAIN RATHER HIGH, LOCAL DOWNPOURS
COULD PUT DOWN A DECENT AMOUNT OF RAIN HOWEVER ANY FLOOD THREAT
LOOKS BRIEF AND LOCALIZED.
AS MENTIONED ABOVE, SOME STRONG CONVECTION MAY OCCUR IN THE EVENING
WITH LOCALLY GUSTY WINDS POSSIBLE. THIS WOULD BE MORE TIED TO ANY
LINE SEGMENTS THAT ARE ABLE TO MAINTAIN THEMSELVES WITH PERHAPS SOME
ENHANCEMENT FROM WATER LOADED DOWNDRAFTS. OTHERWISE, A WEALTH OF
CLOUDS SHOULD BE AROUND THROUGH THE NIGHT FOR MUCH OF THE AREA ALONG
WITH MUGGY CONDITIONS.
AS FOR LOW TEMPERATURES, AN EVEN BLEND OF THE NAM/GFS MOS WAS
GENERALLY USED.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
UNSETTLED WEATHER IS EXPECTED ON MONDAY WITH CONVECTION STILL
POSSIBLE MOST AREAS THROUGH MOST OF THE DAY. LOCALLY HEAVY RAIN IS
POSSIBLE JUST ABOUT ANYWHERE...BUT LATEST GUIDANCE SUGGESTS NEAR AND
SOUTH AND EAST OF THE I-95 CORRIDOR MIGHT BE FAVORED. ANY FLOODING
SHOULD BE MORE URBAN AND POOR DRAINAGE FLOODING. WITH A CONTINUED
SOUTHWESTERLY FLOW, TEMPERATURES WILL PEAK 5 TO 10 DEGREES ABOVE
NORMAL FOR THE BEGINNING OF SEPTEMBER.
MONDAY NIGHT AND TUESDAY...A LULL IN THE PRECIPITATION IS EXPECTED
LATE MONDAY NIGHT THROUGH TUESDAY AFTERNOON. IF THERE`S ENOUGH
SUNSHINE...TEMPERATURES COULD PEAK OUT IN THE LOW 90S.
TUESDAY NIGHT...SHOWERS AND THUNDERSTORMS...SOME WITH LOCALLY HEAVY
RAIN...CAN BE EXPECTED AS A COLD FRONT SWINGS THROUGH THE AREA FROM
WEST TO EAST.
WEDNESDAY THROUGH FRIDAY...THE AIR MASS BEHIND THE COLD FRONT REALLY
WON`T BE TOO MUCH COOLER COURTESY OF A MID-LEVEL ZONAL FLOW, BUT IT
WILL BE DRIER AND MORE COMFORTABLE. HIGHS ALL THREE DAYS WILL BE
PRIMARILY IN THE LOW TO MID 80S, WHICH IS STILL ABOVE NORMAL.
BEAUTIFUL EARLY SEPTEMBER WEATHER.
SATURDAY...INCREASING CLOUDINESS AS THE DAY WEARS ON AS A COLD FRONT
APPROACHES FROM THE WEST. SHOWERS AND THUNDERSTORMS ARE POSSIBLE
WITH TEMPERATURES STILL ABOVE NORMAL.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...AREAS OF MVFR TO LOCAL IFR CEILINGS WILL IMPROVE TO VFR
CEILINGS BY MIDDAY.
AN ISOLATED SHOWER IS POSSIBLE EARLY THIS MORNING MAINLY FROM NEAR
KABE AND KRDG, OTHERWISE SOME SHOWERS AND THUNDERSTORMS ARE EXPECTED
TO CONTINUE TO DEVELOP TO OUR WEST AND OVERSPREAD OUR AREA THIS
AFTERNOON. SOME TIMING WAS INDICATED IN THE TAFS, WITH THUNDER ONLY
MENTIONED AT KABE TO KRDG DUE TO HIGHER CONFIDENCE AS OF NOW. THIS
WILL BE REVISITED LATER THIS MORNING. THERE WILL BE BRIEF TIMES OF
MVFR/IFR VISIBILITIES ESPECIALLY WITHIN SHOWERS AND THUNDERSTORMS
AS DOWNPOURS ARE ANTICIPATED. SOUTH-SOUTHEAST WINDS INCREASING TO
GENERALLY 10-15 KNOTS AND BECOMING SOUTH-SOUTHWEST.
TONIGHT...SHOWERS AND THUNDERSTORMS SHOULD CONTINUE EASTWARD WITH
MUCH OF THE ACTIVITY IN THE EVENING HOURS. AS A RESULT, THERE WILL
BE TIMES OF MVFR/IFR DUE TO DOWNPOURS. IN ADDITION, SOME LIGHT FOG
COULD DEVELOP LATE IF SOME CLEARING OCCURS COMBINED WITH LIGHT
WINDS.
OUTLOOK...
MONDAY INTO MONDAY NIGHT...IFR CONDITIONS EXPECTED WITH SHOWERS AND
THUNDERSTORMS. COVERAGE OF PRECIPITATION DECREASING DURING THE
OVERNIGHT HOURS.
TUESDAY...GENERALLY VFR CONDITIONS EXPECTED DURING THE DAY.
TUESDAY NIGHT...IFR CONDITIONS POSSIBLE AS A COLD FRONT MOVES
THROUGH THE AREA.
WEDNESDAY THROUGH FRIDAY...GENERALLY VFR CONDITIONS EXPECTED.
&&
.MARINE...
A SOUTHERLY FLOW IS EXPECTED THROUGH TONIGHT AHEAD OF A WEAKENING
FRONTAL BOUNDARY AS A DISTURBANCE TRACKS WELL TO OUR NORTH. AS THIS
OCCURS, THE FLOW IS FORECAST TO INCREASE AND THIS OPENS THE DOOR TO
SOME MIXING. IT APPEARS THAT THE WARM AIR ADVECTING ACROSS THE AREA
WILL KEEP THE STRONGER WINDS ABOVE THE SURFACE. WHILE THERE CAN BE
SOME GUSTINESS ESPECIALLY NEARSHORE, IT GENERALLY LOOKS MARGINAL.
THE SOUTHERLY FLOW WILL ALSO ALLOW THE SEAS TO BUILD THROUGH
TONIGHT, HOWEVER GIVEN THE SOUTHERLY FLOW DIRECTION AND FETCH, WE
KEPT SEAS UP TO 4 FEET. THEREFORE, NO SMALL CRAFT ADVISORY HAS BEEN
ISSUED AT THIS TIME. SOME SHOWERS AND THUNDERSTORMS WILL ARRIVE LATE
THIS AFTERNOON AND TONIGHT, AND SOME STORMS COULD PRODUCE LOCALLY
GUSTY WINDS.
OUTLOOK...
MONDAY AND MONDAY NIGHT...WINDS AND SEAS SHOULD REMAIN JUST BELOW
SMALL CRAFT ADVISORY CRITERIA. GUSTIER WINDS POSSIBLE IN THE
VICINITY OF THUNDERSTORMS.
TUESDAY THROUGH THURSDAY...WINDS AND SEAS EXPECTED TO REMAIN BELOW
SCA CRITERIA. HOWEVER, SOME GUSTY WINDS ARE POSSIBLE WITH
THUNDERSTORMS TUESDAY NIGHT AND EARLY WEDNESDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MIKETTA
NEAR TERM...GORSE
SHORT TERM...GORSE
LONG TERM...MIKETTA
AVIATION...GORSE/MIKETTA
MARINE...GORSE/MIKETTA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
345 PM EDT SUN AUG 31 2014
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A PROGRESSIVE NORTHERN
STREAM PATTERN ACROSS THE CONUS OVER THE TOP OF AN ELONGATED WEST TO
EAST ORIENTED UPPER RIDGE EXTENDING FROM NORTHERN MEXICO...ACROSS
THE DEEP SOUTH AND INTO THE WESTERN ATLANTIC. POTENT SHORTWAVE /
MOMENTUM PUSH IS SEEN IN WV IMAGERY EJECTING OUT OF THE
INTER-MOUNTAIN WEST ACROSS THE NORTHERN PLAINS. THIS ENERGY IS
EXPECTED TO RESULT IN A LARGE AREA OF SEVERE POTENTIAL ACROSS THE
NORTHERN PLAINS/UPPER MS VALLEY THIS EVENING. CLOSER TO HOME WE FIND
OUR REGION UNDERNEATH THE ELONGATED UPPER RIDGE MENTIONED
ABOVE...AND THIS RIDGE WILL BE STAYING PUT FOR THE NEXT SEVERAL
DAYS. A SWATH OF MID/UPPER LEVEL DRIER AIR IS CLEARLY SEEN ON WV
IMAGERY ARRIVING OVER THE FL PENINSULA FROM THE EAST... ALTHOUGH THE
12Z KTBW SOUNDING PROFILE WAS LAUNCHED AHEAD OF THIS PUSH...AND
LIKELY DID NOT SAMPLE MUCH OF THE THIS AIRMASS THAT IS NOW STREAMING
OVERHEAD. EVEN STILL...THE 12Z SOUNDING WAS ALREADY DRIER THAN 24
HOURS AGO WITH A PW VALUE DOWN A FEW TENTHS OF AN INCH TO AROUND
1.7".
REGIONAL RADARS SHOWING DISORGANIZED SHOWER/STORM ACTIVITY AHEAD OF
AND ALONG THE EAST COAST SEA-BREEZE WHICH IS QUICKLY TRANSLATING
ACROSS THE STATE THIS MID-AFTERNOON. SHOWERS AND STORMS ARE ALREADY
ARRIVING AROUND THE FORT MYERS AREA AND PROGRESSING WESTWARD THROUGH
POLK/HIGHLANDS/DESOTO/HARDEE COUNTIES FURTHER TO THE NORTH. AS
MENTIONED ABOVE...SO FAR THE CONVECTION IS RATHER DISORGANIZED AND
SHALLOW IN NATURE AS THE SYNOPTIC FLOW IS WITH THE SEA-BREEZE
FLOW...LIMITING LOW LEVEL FOCUS. DO EXPECT A LEAST SOME MORE ROBUST
CONVECTIVE CELLS IN THE NEXT SEVERAL HOURS AS THIS ACTIVITY AND THE
EAST COAST SEABREEZE ARRIVES AT THE I-75 CORRIDOR TO THE NORTH OF
FORT MYERS. HAVE SEEN SEVERAL OF THE COASTAL OBS FLIP AROUND ONSHORE
INDICATING SEA-BREEZE FORMATION...AND THIS SHOULD ENSURE MORE
PRONOUNCED CONVERGENCE FOR STRONG UPDRAFTS / DEEP CONVECTION INTO
THE EARLY EVENING HOURS. WE HAVE MIXED REALLY WELL SO FAR THIS
DIURNAL CYCLE WITH CU BASES AROUND THE REGION GENERALLY AT OR ABOVE
5KFT. THIS SUGGEST WE NOW HAVE A DEEP MIXED LAYER / INVERTED V
PROFILE IN THE LOWER LEVELS. WITH THIS IN MIND...STILL BELIEVE WE
ARE LOOKING AT AN ENHANCED WIND GUST THREAT FROM THE STRONGER
STORMS...AND THIS POTENTIAL WILL NEED TO BE WATCHED CLOSELY ON RADAR
THROUGH THE EARLY EVENING PERIOD.
&&
.SHORT TERM (TONIGHT AND MONDAY)...
ANY LINGERING STORMS WILL BE QUICKLY EXITING INTO THE GULF WITHIN A
COUPLE HOURS OF SUNSET...WHICH WILLS SET UP A MOSTLY DRY AND
SEASONABLE OVERNIGHT PERIOD. SIMILAR TO SATURDAY NIGHT...STORMS MAY
LINGER FOR A FEW EXTRA HOURS UP OVER THE COASTAL NATURE COAST BEFORE
EVEN HERE THE ACTIVITY DIMINISHES AND PUSHES OFFSHORE. WITH THE FAST
PROGRESSION OF ACTIVITY FROM EAST TO WEST...THE DURATION OF RAINFALL
FOR ANY ONE LOCATIONS DOES NOT LOOK TO BE ALL THAT GREAT...HOWEVER
THE CHANCES FOR A PASSING STORM ARE FAIRLY HIGH...ESPECIALLY FROM
PASCO/HERNANDO COUNTIES SOUTHWARD. CURRENT GRIDS SHOWS 60-70%
COVERAGE THE NEXT SEVERAL HOURS...AND FEEL THIS FORECAST IS STILL
VALID.
THE OVERALL SYNOPTIC PATTERN DOES NOT CHANGE MUCH HEADING INTO
LABOR DAY...AND HENCE NEITHER WILL THE FORECAST. EASTERLY FLOW WILL
CONTINUE TO DOMINATE THE REGION ON THE SOUTHERN SIDE OF THE
SUBTROPICAL RIDGE AXIS LOCATED NEAR THE I-10 CORRIDOR. MANY OF THE
THERMODYNAMIC PARAMETERS THROUGH THE COLUMN LOOK SIMILAR TO TODAY
SUGGESTING WIND WILL AGAIN BE THE PRIMARY THREAT WITH ANY OF THE
STRONGER STORMS. FORECAST WILL SHOW A QUIET AND MAINLY RAIN FREE
MORNING AND EARLY AFTERNOON...FOLLOWED BY INCREASING STORM CHANCES
ARRIVING FROM THE EAST WITH THE SEA-BREEZE. THE PEAK OF THE STORMS
SHOULD AGAIN FALL BETWEEN 2 AND 6 PM TO THE SOUTH OF SARASOTA...AND
4 TO 8 PM FURTHER NORTH THROUGH THE I-4 CORRIDOR AND UP INTO THE
NATURE COAST.
&&
.LONG TERM (TUESDAY NIGHT THROUGH SATURDAY)...
NOT MUCH CHANGE FOR THE ONGOING LONG TERM FORECAST. THE ATLANTIC
SURFACE RIDGE WILL REMAIN GENERALLY NORTHEAST OF THE AREA...WITH
EAST OR SOUTHEAST FLOW CONTINUING. A MID/UPPER-LEVEL LOW WILL MAKE
ITS WAY WEST-NORTHWESTWARD TOWARD THE EAST COAST OF FLORIDA THROUGH
MID TO LATE WEEK. THE GFS SHOWS A MORE WELL-DEFINED FEATURE WITH 500
MB TEMPS COOLING SLIGHTLY TO -8 DEGREES CELSIUS OVER OUR
SOUTHERNMOST ZONES WHILE THE ECMWF IS NOT QUITE AS DEFINED BUT DOES
STILL SHOW SOME COOL TEMPS ALOFT OF AROUND -7. ANOTHER FACTOR FOR
WEDNESDAY WILL BE THE DRIER AIR THAT MOVES OVER THE REGION...WHICH
WOULD TEND TO SCALE BACK POPS A BIT...THOUGH STILL IN THE SCATTERED
RANGE...BUT SOME OF THE STORMS THAT DO FORM COULD BE ON THE STRONGER
SIDE WITH THE COOLING 500 MB TEMPS. OTHERWISE...EXPECT FAIRLY
TYPICAL SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WITH AN
EAST TO SOUTHEAST FLOW. TEMPERATURES LOOK TO REMAIN AROUND NORMAL
VALUES FOR THE PERIOD.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE FORECAST AREA LATE THIS MORNING AS
WE AWAIT MORE LATE DAY STORMS. STORMS LATE THIS AFTERNOON AND EARLY
EVENING WILL HAVE AN ENHANCED WIND THREAT. OTHERWISE...AWAY FROM THE
STORMS EXPECT VFR CONDITIONS TO CONTINUE. STORMS WILL PUSH OFFSHORE
WITHIN A COUPLE HOURS OF SUNSET.
&&
.MARINE...
HIGH PRESSURE RIDGING ACROSS THE NORTHEASTERN GULF OF MEXICO AND
FLORIDA PENINSULA WILL KEEP WINDS LESS THAN 15 KNOTS AND SEAS BELOW
3 FEET FOR THE NEXT SEVERAL DAYS. THE SEA BREEZE WILL SET UP ALONG
THE COASTLINE EACH DAY TURNING THE WINDS TO AN ONSHORE FLOW IN THE
AFTERNOON. SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE EACH DAY
DEVELOPING OVER LAND AND THEN PUSHING WESTWARD OVER THE COASTAL
WATERS DURING THE EVENING HOURS. THE ONLY EXPECTED HAZARD WILL BE
GUSTY WINDS AND HIGHER SEAS IN THE VICINITY OF THUNDERSTORMS.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL REMAIN ALIGNED OVER THE NORTHERN PORTION OF THE
STATE THROUGH THE MIDDLE OF THE WEEK. THIS PATTERN WILL KEEP AMPLE
ATLANTIC LOW LEVEL MOISTURE IN PLACE TO PREVENT ANY CRITICAL LEVELS
OF RELATIVE HUMIDITY. THUNDERSTORMS WILL BE MOST LIKELY ALONG THE
I-75 CORRIDOR DURING THE LATE AFTERNOON AND EVENING HOURS THE NEXT
SEVERAL DAYS.
FOG POTENTIAL...PATCHY GROUND FOG COULD DEVELOP LATE EACH
NIGHT...ESPECIALLY IN LOCATIONS THAT RECEIVE RAIN DURING THE
PREVIOUS EVENING. HOWEVER...NO SIGNIFICANT FOG IS ANTICIPATED
THROUGH THE MIDDLE OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 77 93 78 92 / 30 50 20 50
FMY 75 94 76 92 / 10 60 10 50
GIF 75 94 75 93 / 10 50 10 40
SRQ 75 92 76 91 / 30 60 20 50
BKV 72 93 73 93 / 40 50 20 40
SPG 79 93 80 91 / 40 60 30 50
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/FIRE WX...MROCZKA
MARINE...FLEMING
LONG TERM...CARLISLE
AREA FORECAST DISCUSSION...CORRECTED
NWS TAMPA BAY RUSKIN FL
1100 AM EDT SUN AUG 31 2014
.UPDATE...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A PROGRESSIVE NORTHERN
STREAM PATTERN ACROSS THE CONUS OVER THE TOP OF AN ELONGATED WEST TO
EAST ORIENTED UPPER RIDGE EXTENDING FROM NORTHERN MEXICO...ACROSS
THE DEEP SOUTH AND INTO THE WESTERN ATLANTIC. POTENT SHORTWAVE /
MOMENTUM PUSH IS SEEN IN WV IMAGERY EJECTING OUT OF THE
INTER-MOUNTAIN WEST ACROSS THE NORTHERN PLAINS. THIS ENERGY IS
EXPECTED TO RESULT IN A LARGE AREA OF SEVERE POTENTIAL ACROSS THE
NORTHERN PLAINS/UPPER MS VALLEY LATER TODAY INTO TONIGHT. CLOSER TO
HOME WE FIND OUR REGION UNDERNEATH THE ELONGATED UPPER RIDGE
MENTIONED ABOVE...AND THIS RIDGE WILL BE STAYING PUT FOR THE NEXT
SEVERAL DAYS. A SWATH OF MID/UPPER LEVEL DRIER AIR IS CLEARLY SEEN
ON WV IMAGERY ARRIVING OVER THE FL PENINSULA FROM THE EAST...
ALTHOUGH THE 12Z KTBW SOUNDING PROFILE WAS LAUNCHED AHEAD OF THIS
PUSH...AND LIKELY DID NOT SAMPLE MUCH OF THE THIS AIRMASS THAT IS
NOW STREAMING OVERHEAD. EVEN STILL...THE 12Z SOUNDING WAS ALREADY
DRIER THAN 24 HOURS AGO WITH A PW VALUE DOWN A FEW TENTHS OF AN INCH
TO AROUND 1.7".
CONVECTIVE POTENTIAL TODAY IS A BIT TRICKY. NO DOUBT THAT WE WILL
SEE STORMS DEVELOPING IN THE FAVORED EASTERLY FLOW...HOWEVER...
TODAYS COLUMN PER THIS 12Z SOUNDING IS NOT AS FAVORABLE FOR
SUSTAINED DEEP CONVECTION AS WAS SEEN ON SATURDAY. THE MID LEVELS
TODAY ARE A BIT WARMER AND ALSO A BIT DRIER. IN ADDITION...THE LOWER
LEVELS BELOW 700MB SHOW A BIT OF A WARM/DRY BUBBLE/CAP. DO NOT THINK
THAT THIS CAP WILL BE ENOUGH TO STOP CONVECTION...BUT SHOULD
CERTAINLY WORK TO DELAY ITS ONSET. WILL NEED TO MIX THE BOUNDARY
LAYER A BIT HIGHER TO OVERCOME THIS CIN COMPARED TO YESTERDAY. FEEL
THIS LATER DEVELOPMENT WILL BE THE MAIN DIFFERENCE BETWEEN YESTERDAY
AND TODAY.
SO...THE COLUMN IS A BIT DRIER...BUT NOT ENOUGH TO BE CONSIDERED
HOSTILE TO DEEP CONVECTION. ONE CONCERN WITH HAVING TO MIX OUT THE
LOWER LEVELS MORE TO REACH THE CONVECTIVE TEMPERATURE IS THAT WE
WILL END UP WITH A DEEPER INVERTED V SIGNATURE / MIXED LAYER BY LATE
AFTERNOON. THESE HIGHER CLOUD BASES AND DEEP WELL MIXED LAYER WILL
PROMOTE AN ENHANCED WIND THREAT WITH THESE LATE DAY STORMS. AS
MENTIONED ABOVE...WE ARE SEEING A WELL DEFINED EAST TO SOUTHEAST
1000-700MB SYNOPTIC FLOW TODAY...AND THIS PATTERN IS FAVORED FOR
CONVECTIVE DEVELOPMENT ALONG THE I-75 CORRIDOR AS THE FLOW INTERACTS
WITH A FEEBLE WEST COAST SEA-BREEZE.
HIRES CONVECTIVE ALLOWING SUITE OF MODELS SEEM TO BE PINNING THE
I-75 CORRIDOR FROM AROUND TAMPA BAY AND SOUTHWARD FOR THE GREATEST
COVERAGE OF STORMS DURING THE LATE AFTERNOON/EARLY EVENING. MANY OF
THESE MEMBERS ARE MUCH LESS AGGRESSIVE UP ALONG THE NATURE COAST.
NOW THERE IS DEFINITELY A TREND HERE...BUT OVERALL DO NOT SEE MUCH
DIFFERENCE IN AIRMASS. PERHAPS A BIT GREATER OVERALL SUPPRESSION IN
CLOSER PROXIMITY TO THE UPPER RIDGE AXIS IS MAKING A DIFFERENCE IN
THESE SIMULATIONS...BUT THIS SHOULD BE MINOR. WITH THE MORNING
FORECAST UPDATE HAVE KEEP RAIN CHANCES LATER TODAY OUT OF THE LIKELY
RANGE (GREATER THAN 60%) TO THE NORTH OF PASCO COUNTY...BUT DO NOT
FEEL COMFORTABLE GOING LESS THAN CHANCE 40-50% FOR THESE NORTHERN
ZONES. HOWEVER...SIMILAR TO SATURDAY...AS YOU HEAD NORTH THROUGH THE
NATURE COAST...MUCH OF THE STORM ACTIVITY SHOULD BE INTO THE EVENING
HOURS. IN CONTRAST...THE AREAS SOUTH OF TAMPA BAY...ESPECIALLY
HIGHLAND COUNTY OVER TO THE FORT MYERS AREAS WILL BE FIRST TO SEE
THE CONVECTIVE INITIATION DURING THE EARLY TO MIDDLE AFTERNOON
HOURS.
THE MORNING SOUNDING SHOWS DEEP LAYER EAST/SE FLOW THROUGH THE
COLUMN...AND THE RAP KEEPS THIS GOING THROUGH THE DAY.
THEREFORE...THERE IS LITTLE DOUBT IN THE PREVAILING STORM MOTION
FROM ESE TO WNW TODAY. BOATERS ON THE COASTAL WATERS SHOULD KEEP A
CLOSE EYE TO THE EAST LATE THIS AFTERNOON/EARLY EVENING AS ANY
STORMS WILL BE MOVING QUICKLY IN YOUR DIRECTION AND PUSHING OFFSHORE
WITH TIME.
ANY LINGERING STORMS WILL BE QUICKLY EXITING INTO THE GULF WITHIN A
COUPLE HOURS OF SUNSET...WHICH WILLS SET UP A MOSTLY DRY AND
SEASONABLE OVERNIGHT PERIOD.
THE OVERALL SYNOPTIC PATTERN DOES NOT CHANGE MUCH HEADING INTO LABOR
DAY...AND HENCE NEITHER WILL THE FORECAST. EASTERLY FLOW WILL
PROMOTE A QUIET MORNING AND THEN MAINLY LATE AFTERNOON/EVENING
STORMS. MORE ON THE MONDAY DETAILS WITH THE AFTERNOON DISCUSSION.
HAVE A GREAT SUNDAY AND WATCH OUT FOR THOSE GUSTY LATE DAY STORMS.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE FORECAST AREA LATE THIS MORNING AS
WE AWAIT MORE LATE DAY STORMS. STORMS LATE THIS AFTERNOON AND EARLY
EVENING WILL HAVE AN ENHANCED WIND THREAT. OTHERWISE...AWAY FROM THE
STORMS EXPECT VFR CONDITIONS TO CONTINUE. STORMS WILL PUSH OFFSHORE
WITHIN A COUPLE HOURS OF SUNSET.
&&
.MARINE...
EAST SOUTHEAST WINDS LESS THAN 15 KNOTS AND SEAS LESS THAN 3 FEET
WILL CONTINUE FOR THE NEXT SEVERAL DAYS AS HIGH PRESSURE OVER THE
ATLANTIC RIDGES WEST OVER THE FLORIDA PENINSULA. THE SEA BREEZE WILL
SET UP ALONG THE COASTLINE EACH DAY TURNING THE WINDS TO AN ONSHORE
FLOW OUT OF THE SOUTHWEST THROUGH NORTHWEST DIRECTION. SCATTERED
SHOWERS AND STORMS WILL BE POSSIBLE EACH DAY DEVELOPING OVER LAND
AND THEN PUSHING WESTWARD OVER THE COASTAL WATERS DURING THE EVENING
HOURS. THE ONLY EXPECTED HAZARD WILL BE GUSTY WINDS AND HIGHER SEAS
IN THE VICINITY OF THUNDERSTORMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 93 76 93 78 / 70 30 50 40
FMY 94 75 94 76 / 70 10 50 30
GIF 94 75 94 75 / 40 10 40 10
SRQ 94 74 93 76 / 70 30 50 40
BKV 94 72 94 73 / 50 40 40 30
SPG 93 79 93 80 / 70 40 50 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...MROCZKA
MARINE...WYNN
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
239 PM EDT SUN AUG 31 2014
.SYNOPSIS...
A PERSISTENT UPPER RIDGE WILL KEEP VERY WARM TEMPERATURES IN THE
FORECAST THIS WEEK. INCREASED LOW LEVEL MOISTURE WILL RESULT IN
CHANCES OF AFTERNOON STORMS AND HUMID CONDITIONS WITH HEAT INDICES
AT OR ABOVE 100 DEGREES.
&&
.NEAR TERM /THROUGH TONIGHT/...
WATER VAPOR IMAGERY EARLY THIS AFTERNOON INDICATES THE UPPER RIDGE
AXIS IS RIGHT OVERHEAD EXTENDING FROM SOUTHEAST VIRGINA THROUGH
THE CENTRAL CAROLINAS INTO SOUTHERN GEORGIA. PRECIPITABLE WATER
AXIS JUST UNDER 2 INCHES EXTENDS NORTHWARD ALONG THE I-20 CORRIDOR
AND REGIONAL RADAR SHOWING SCATTERED SHOWERS DEVELOPING ALONG THIS
AXIS IN SOUTHEAST GEORGIA INTO THE CSRA. HRRR HAD A GOOD HANDLE ON
THIS AND HAVE HIGHEST POPS THIS AFTERNOON IN THE SOUTHEAST PORTION
OF THE FORECAST AREA BUT STILL MAINTAINING CHANCE POPS. UPPER FLOW
REMAINS VERY WEAK WITH STORM MOTION GENERALLY 5 KNOTS OR LESS AND
CONVECTION HAS BEEN GOING UP AND RIGHT BACK DOWN FAIRLY QUICKLY AS
THEY RAIN THEMSELVES OUT. THINK SEVERE THREAT REMAINS LOW GIVEN
SUCH WARM AIR IN THE LOWER 20KFT AND SURFACE TEMPERATURES PUSHING
INTO THE MID AND UPPER 90S.
SOME LINGERING SHOWERS MAY EXIST THROUGH THE LATE EVENING HOURS
BUT EXPECT PRECIPITATION TO END BY 06Z OR SO WITH SOME CONVECTIVE
DEBRIS CLOUD OVER THE AREA TONIGHT. TEMPERATURES WILL BE WARM
AGAIN TONIGHT IN THE LOW TO MID 70S AFTER SUCH A WARM DAY WITH
CLOUD COVER AND ABUNDANT LOW LEVEL MOISTURE LIMITING RADIATIONAL
COOLING.
&&
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
STRONG MID/UPPER LEVEL RIDGE CONTINUES TO HOLD ALONG THE
SOUTHEAST COAST INTO MONDAY NIGHT. S/W ENERGY ACROSS THE CNTRL/NRN
PLAINS WILL CONTINUE TO MOVE EASTWARD ACROSS THE GREAT LAKES AND
FLATTEN OUT THE AMPLITUDE OF THE RIDGE...BUT THE SOUTHEAST REMAINS
UNDER HIGHER HEIGHTS AND SEPARATE FROM THE MAIN W TO E FLOW. LOW
LEVEL FLOW REMAINS FROM THE SOUTH TO SOUTH-SOUTHWEST THROUGH THE
PERIOD. THIS WILL HELP TO KEEP LOW LEVEL MOISTURE IN PLACES WITH
DEWPOINTS RANGING FROM THE MIDDLE 60S TO LOWER 70S.
HOWEVER...CHANCES FOR SHOWERS/THUNDERSTORMS LOOK LOW THROUGH THE
PERIOD. GUIDANCE POPS ALONG WITH LACK OF UPPER TRIGGERS
INDICATING ONLY SLIGHT CHANCE POPS THROUGH THE PERIOD. CONVECTIVE
ACTIVITY WILL BE MAINLY DIURNAL IN NATURE WITH ONLY SOME WEAK
SURFACE CONVERGENCE/SEA BREEZE ACTION EACH DAY. AS FOR
TEMPERATURES...EXPECT AFTERNOON TEMPERATURES TO CONTINUE THE RUN
OF 5 TO 10 DEGREES ABOVE NORMAL. AS HIGHS THIS AFTERNOON HAVE
CLIMBED INTO THE UPPER 90S IN SOME AREAS...DECIDED TO RAISE
AFTERNOON HIGHS FOR MONDAY BASED ON CURRENT TRENDS AND BOUNDARY
LAYER/H8 TEMPS. EXPECT MIDDLE TO UPPER 90S ACROSS MOST LOCATIONS.
LIKE THIS AFTERNOON A LOCATION OR TWO MAY REACH THE CENTURY MARK.
OVERNIGHT LOWS WILL BE IN THE LOWER 70S. AFTERNOON HEAT INDEX
VALUES TOMORROW WILL CLIMB TO AROUND 105 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
NO REAL CHANGES TO THE EXTENDED FORECAST. UPPER RIDGE CONTINUES
OVER THE AREA FROM TUESDAY THROUGH NEXT WEEKEND. IN FACT THE RIDGE
BEGINS TO AMPLIFY ONCE AGAIN BEGINNING WEDNESDAY THROUGH FRIDAY.
THE THE MAIN FLOW ACROSS THE NORTHERN HALF OF THE U.S....EXPECT
S/W ACTIVITY TO REMAIN NORTH OF THE AREA FROM THE NRN PLAINS AND
GREAT LAKES INTO NEW ENGLAND/MID ATLANTIC REGION AND REMAINING
NORTH OF THE CWA. LOW-LEVEL MOISTURE CONTINUES TO SLOWLY INCREASE
DURING THE BEGINNING OF THE PERIOD AND REMAIN BETWEEN 1.5 AND 2.0
INCHES THROUGH THE WEEK AND INTO THE WEEKEND. A WEAK BOUNDARY
TRIES TO MOVE SOUTHWARD INTO THE REGION WEDNESDAY...BUT MODELS
CONTINUE TO SHOW IT HANGING UP JUST NORTH AND WEST OF THE CWA.
REMNANTS OF BOUNDARY LINGER JUST NORTH OF THE CWA THROUGH MUCH OF
THE WEEK. OTHERWISE...JUST A SLIGHT CHANCE/LOW CHANCE POPS THROUGH
THE PERIOD. STILL LOOKS TO BE DIURNAL IN NATURE WITH AFTERNOON
HEATING WITH WEAK SURFACE CONVERGENCE AND LITTLE/NO UPPER SUPPORT.
TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL THROUGH THE
REMAINDER OF THE LONG TERM PERIOD. EXPECT AFTERNOON HIGHS IN THE
LOW/MID 90S AND OVERNIGHT LOWS IN THE LOW/MID 70S. NORMALS HIGHS
ARE IN THE UPPER 80S AND LOWS NEAR 70.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS THROUGH MUCH OF THE PERIOD EXPECTED WITH ISOLATED
SHOWERS 18Z-02Z. HAVE INCLUDED VCSH AT CAE/CUB/AGS/DNL WITH RADAR
INDICATING CONVECTION DEVELOPING ALONG A WEAK CONVERGENCE LINE
POSITIONED ALONG THE I-20 CORRIDOR. THINK THE STRENGTH OF THE
UPPER RIDGE OVERHEAD WILL LIMIT CONVECTION AND POSSIBILITY OF
THUNDER SO NOT MENTIONING AT THIS TIME. SOUTHERLY WINDS AROUND 5
TO 10 MPH THIS AFTERNOON BECOMING LIGHT AND VARIABLE OVERNIGHT.
EXPECT SOME LIGHT MVFR FOG TO DEVELOP LATE TONIGHT GIVEN ABUNDANT
BOUNDARY LAYER MOISTURE IN PLACE...ALTHOUGH POSSIBLE DEBRIS CLOUDS
MAY IMPACT FOG POTENTIAL LEADING TO LOWER CONFIDENCE.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN LATE NIGHT
AND EARLY MORNING STRATUS AND FOG. SCATTERED MAINLY AFTERNOON
SHOWERS AND THUNDERSTORMS SUNDAY THROUGH THURSDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
150 PM CDT SUN AUG 31 2014
.DISCUSSION...
328 AM CDT
AFTER A FAIRLY QUIET DAY ACROSS THE AREA TODAY...ATTENTION QUICKLY
SHIFTS TO THE WEATHER FOR LABOR DAY INTO MONDAY NIGHT...DURING WHICH
PERIODS OF EXTREMELY HEAVY RAINFALL AND SEVERE WEATHER ARE POSSIBLE.
THUNDERSTORMS CONTINUED TO TRAIN ACROSS THE SAME AREAS ACROSS
PORTIONS OF FORD AND IROQUOIS COUNTIES IN ILLINOIS AND ALSO BENTON
COUNTY IN INDIANA YESTERDAY EVENING AND INTO THE OVERNIGHT HOURS.
THESE AREAS LIED IN THE RIGHT ENTRANCE REGION OF AN UPPER LEVEL JET
STREAK. THE COMBINATION OF THIS...AND THE CONTINUED LOW LEVEL
CONFLUENCE CONTINUED TO DRIVE THIS CONVECTION. RADAR ESTIMATES SOME
VERY HEFTY ISOLATED RAINFALL AMOUNTS IN EXCESS OF 4 INCHES ACROSS
PORTIONS OF THESE COUNTIES. ALTHOUGH SOME ISOLATED ACTIVITY
CONTINUES ACROSS THIS AREA AS OF THIS WRITING...IT IS EXPECTED THAT
ALL THIS ACTIVITY WILL SHIFT OUT OF THE AREA AROUND...OR JUST PRIOR
TO DAYBREAK AS THE UPPER LEVEL JET DEVELOPS EASTWARD.
WATER VAPOR IMAGERY EARLY THIS MORNING SHOWS THE NEXT UPPER LEVEL
SYSTEM CURRENTLY DIGGING ACROSS THE ROCKIES. AIRCRAFT AND UPPER AIR
OBSERVATIONS ACROSS WESTERN CANADA AND OVER THE NORTHEAST PACIFIC
INDICATE SOME IMPRESSIVE UPPER LEVEL WINDS...FOR THIS TIME OF
YEAR...IN EXCESS OF 110 KT WITHIN THE CORE OF THE JET STREAK
DIGGING OVER THE WESTERN CONUS. THE FIRST MID LEVEL IMPULSE IS
EXPECTED TO CONTINUE SHIFTING EASTWARD OVER THE UPPER MIDWEST INTO
MONDAY MORNING. AS IT DOES SO...IT WILL DRIVE A FAIRLY STOUT
SURFACE LOW NORTHEASTWARD FROM THE DAKOTAS TO ONTARIO. SOME VERY
SUBSTANTIAL CONVECTION IS EXPECTED TO DEVELOP AHEAD OF THE COLD
FRONT LATER TODAY ACROSS PORTIONS OF THE MID MISSOURI VALLEY AND
INTO MINNESOTA. THIS ACTIVITY WILL LIKELY SHIFT EAST-NORTHEASTWARD
OVERNIGHT TONIGHT...WITH SOME OF THE REMNANT ACTIVITY POSSIBLY
REACHING NORTH CENTRAL ILLINOIS BY AROUND...OR JUST PRIOR TO
DAYBREAK MONDAY. IT APPEARS THAT THIS INITIAL ROUND OF CONVECTION
COULD BE IN A WEAKENING PHASE AS IT TRIES TO PUSH OVER PORTIONS
OF NORTHERN ILLINOIS MONDAY MORNING. HOWEVER...RENEWED CONVECTIVE
DEVELOPMENT...POSSIBLY ALONG ANY OUTFLOW BOUNDARIES LAID DOWN BY
EARLY MORNING ACTIVITY...IS LIKELY ACROSS PORTIONS OF NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA BY MONDAY AFTERNOON.
MODEL SOUNDINGS ALL INDICATE FAVORABLE PROFILES FOR ACTIVE STRONG TO
SEVERE STORMS OVER THE AREA DURING THE AFTERNOON AND EARLY EVENING
MONDAY. DEEP LAYER BULK SHEAR LOOKS TO BE SOMEWHAT
UNIDIRECTIONAL...BUT WITH 0-6 KM SPEED SHEAR OF NEARLY 50
KT...ORGANIZED CONVECTIVE ACTIVITY APPEARS VERY POSSIBLE. THE MAIN
COMPLICATING FACTOR AT THIS POINT IS HOW MUCH ANY CLOUD DEBRIS OR
REMNANT MORNING CONVECTIVE ACTIVITY IMPACTS AFTERNOON HEATING AND
DESTABILIZATION ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN
INDIANA. HOWEVER...IN SPITE OF THIS POSSIBILITY EARLY IN THE
DAY...IT DOES APPEAR THAT THE HIGH THETA E NEAR SURFACE AIR MASS
SHOULD BE ENOUGH TO PRODUCE AMPLE MLCAPE VALUES AT OR JUST IN
EXCESS OF 1500 J/KG...WHICH COMBINED WITH THE 45+ DEEP LAYER SHEAR
CERTAINLY POINTS TO A SEVERE THREAT. AT THIS TIME IT APPEARS
RATHER MODEST MID LEVEL LAPSE RATES WOULD RESULT IN THE MAIN
SEVERE THREAT BEING STRONG DAMAGING WIND GUSTS. HOWEVER...THERE IS
ALSO A SECONDARY THREAT OF LARGE HAIL...ESPECIALLY IF ANY SUPER
CELLS CAN FORM.
THERE IS ALSO A DECENT CONCERN FOR EXTREMELY HEAVY RAINFALL RATES
WITH THESE STORMS...WITH PWAT VALUES IN THIS JUICY ENVIRONMENT
LIKELY TO RESIDE AROUND 1.7 INCHES. NUMERICAL GUIDANCE CONTINUES TO
SUGGEST THAT A SECONDARY MID LEVEL IMPULSE WILL APPROACH THE AREA
MONDAY NIGHT AND ACT TO INDUCE/STRENGTHEN A SOUTHWESTERLY UPPER
LEVEL JET STREAK ACROSS THE GREAT LAKES REGION INTO MONDAY NIGHT.
THIS PROCESS COULD SET UP PORTIONS OF THE AREA WITHIN THE FAVORABLE
RIGHT ENTRANCE REGION OF A 100 KT UPPER LEVEL JET INTO TUESDAY
MORNING AS THE SURFACE COLD FRONTAL BOUNDARY SLOWLY TRIES TO SHIFT
SOUTHWARD ACROSS THE SOUTHERN HALF OF MY CWA. I HAVE INCREASING
CONCERNS THAT THIS COULD SET UP A VERY HEAVY RAIN EVENT MONDAY
NIGHT...WITH STORMS POTENTIALLY TRAINING TO THE EAST NORTHEAST
NEARLY PARALLEL TO THE SURFACE BOUNDARY. AT THIS TIME IT APPEARS THIS
HEAVY RAIN THREAT COULD END UP SOUTH OF INTERSTATE 80 MONDAY NIGHT.
HOWEVER...UNCERTAINTY IS STILL A BIT HIGH AS TO HOW FAR SOUTH THE
SURFACE FRONT WILL GET MONDAY NIGHT...AND HENCE WHERE THE MOST
FAVORED AREAS FOR TRAINING CELLS WILL OCCUR. AT THIS POINT...I HAVE
ADDED HEAVY RAIN WORDING TO THE FORECAST...MAINLY FOR AREAS SOUTH OF
INTERSTATE 80 INTO MONDAY NIGHT.
FOLLOWING THIS ACTIVE WEATHER MONDAY NIGHT IT APPEARS THE WEATHER
WILL BE DRY FOR THE MOST PART THROUGH LATE WEEK. THE MAIN STORY
HOWEVER...WILL BE THE INCREASING HEAT BY THURSDAY. FORECAST GUIDANCE
CONTINUES TO FORECAST MID LEVEL HEIGHTS TO BUILD SUBSTANTIALLY
ACROSS THE CENTRAL CONUS. THIS COULD LEAD TO A RUN AT
90 TEMPERATURES FOR THURSDAY AS 850 MB TEMPERATURES WARM TO 20 TO
22C. I HAVE STARTED CUTTING BACK ON THE SLIGHT CHANCE
POPS...ESPECIALLY ON WEDNESDAY AND WEDNESDAY NIGHT...BUT LEFT IN
SOME SLIGHTS FOR THURSDAY. ALTHOUGH SOME ISOLATED CONVECTIVE
ACTIVITY IS POSSIBLE DURING THIS TIME...IT APPEARS THAT THE BUILDING
HEIGHTS AND WARMING TEMPS ALOFT COULD END UP CAPPING THE AREA...AND
LIMITING THE THREAT FOR CONVECTIVE DEVELOPMENT THROUGH THURSDAY.
CONVECTIVE CHANCES DO LOOK TO RETURN TO THE AREA AGAIN BY FRIDAY.
ANOTHER SIGNIFICANT WAVE IS EXPECTED TO SHIFT EASTWARD ACROSS THE
NORTHERN CONUS AND SOUTHERN CANADA LATE IN THE PERIOD...AND THIS
LOOKS TO SHIFT A COLD FRONT SOUTHWARD ACROSS THE AREA SOMETIME
EITHER FRIDAY OR FRIDAY NIGHT AND THIS COULD SPARK OFF ACTIVITY
ACROSS THE AREA. COOLER WEATHER DOES LOOK TO OVERSPREAD TO AREA
UNDER NORTHERLY WINDS BY EARLY NEXT WEEKEND.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* LAKE BREEZE THIS AFTERNOON AND WHETHER OR NOT IT WILL PUSH
ACROSS ORD/MDW.
* GUSTY SOUTHWEST WINDS DEVELOPING MID MORNING MONDAY.
* CHANCES FOR THUNDERSTORMS...WITH A LOWER CHANCE OF LINGERING
PRECIP COMING IN TOMORROW MORNING...AND A BETTER CHANCE FOR NEW
DEVELOPMENT OF STRONG THUNDERSTORMS MONDAY AFTERNOON.
BMD
//DISCUSSION...UPDATED 18Z...
THIS AFTERNOON...WEAK HIGH PRESSURE IS IN PLACE TODAY ALLOWING FOR
GENERALLY LIGHT SOUTHWEST FLOW. A LAKE BREEZE HAS ALREADY
DEVELOPED THOUGH REMAINS FAIRLY CLOSE TO THE SHORE AT THIS HOUR.
IT IS UNCERTAIN WHETHER IT WILL MAKE IT ACROSS THE TERMINALS BUT
MOST GUIDANCE IS LEANING AGAINST THIS OCCURRING...AND IF IT DOES IT
WOULD LIKELY BE LATE.
ATTENTION TURNS TO THE WEST TONIGHT AS AN UPPER LEVEL DISTURBANCE
PUSHES ACROSS THE PLAINS KICKING OFF THUNDERSTORMS. THESE
THUNDERSTORMS ARE EXPECTED TO PERSIST THROUGH THE OVERNIGHT HOURS
MOVING INTO NORTHERN ILLINOIS EARLY MONDAY MORNING IN A DISSIPATING
STAGE. RFD HAS BEST CHANCE FOR SEEING SOME FESTERING EARLY MORNING
ACTIVITY SO ADDED A PROB30 FOR TSRA. DEPENDING ON HOW FAR EAST THIS
PRECIP MAKES IT EARLY MONDAY...EXPECT THE ATMOSPHERE TO RECOVER
BECOMING MODERATELY UNSTABLE WITH ADDITIONAL THUNDERSTORMS EXPECTED
TO REDEVELOP MONDAY AFTERNOON. THESE STORMS COULD BE STRONG TO
SEVERE WITH GUSTY WINDS THE PRIMARY THREAT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* LOW CONFIDENCE IN LAKE BREEZE MAKING IT THROUGH ORD/MDW TODAY.
* LOW-MEDIUM CONFIDENCE IN CIGS REST OF TODAY.
* MEDIUM-HIGH CONFIDENCE IN WIND SPEEDS AND DIRECTION MONDAY.
* HIGH CONFIDENCE IN AT LEAST A PERIOD OF TSRA BUT LOW CONFIDENCE
IN SPECIFIC TIMING.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...CHANCE SHRA/TSRA.
TUESDAY AND WEDNESDAY...VFR. WX NIL.
THURSDAY THROUGH SATURDAY...PERIODIC CHANCES FOR SHRA/TSRA.
KREIN
&&
.MARINE...
149 PM CDT
THE WEATHER PATTERN ACROSS THE WESTERN LAKES WILL BE FAIRLY
PROGRESSIVE OVER THE NEXT SEVERAL DAYS...WITH A PAIR OF SURFACE LOWS
PASSING ACROSS OR NORTH OF THE NORTHERN LAKES AND TRAILING COLD
FRONTS ACROSS LAKE MICHIGAN.
THE FIRST LOW...OVER FAR NORTHWEST MINNESOTA THIS AFTERNOON...WILL
MOVE NORTHEAST ACROSS ONTARIO AND THE NORTHERN LAKES THROUGH MONDAY
WITH ITS TRAILING COLD FRONT PUSHING SOUTHEAST ACROSS THE LAKE
MONDAY AFTERNOON AND EVENING. TIGHTENING OF THE GRADIENT AHEAD OF
THE LOW AND FRONTAL TROUGH WILL RESULT IN SOUTHERLY WINDS INCREASING
LATE TONIGHT AND MONDAY...WITH GUSTS REACHING THE 20-25 KT RANGE AND
CONTINUING INTO EARLY MONDAY EVENING BEFORE THE GRADIENT WEAKENS
ALONG THE COLD FRONTAL TROUGH. THIS FRONT WILL PUSH SOUTHEAST ACROSS
THE LAKE MONDAY NIGHT...WITH LIGHTER WINDS OVERNIGHT AND TUESDAY AS
A BUBBLE HIGH MOVES ACROSS THE AREA BEHIND THE FRONT.
THE HIGH WILL MOVE OFF TO THE EAST WEDNESDAY MORNING...WITH WINDS
BECOMING SOUTH AND STRENGTHENING TO 20-25 KT AGAIN LATER IN THE
WEDNESDAY AND CONTINUING INTO THURSDAY BEFORE THE NEXT SURFACE LOW
PASSES NORTH OF THE LAKES AND ITS TRAILING COLD FRONT MOVES THROUGH
LATE THURSDAY NIGHT AND EARLY FRIDAY. WINDS DONT LOOK TO BE TOO
STRONG IMMEDIATELY BEHIND THIS SECOND FRONT...THOUGH A PERIOD OF
ENHANCED NORTHERLY WINDS IS POSSIBLE SATURDAY AS HIGH PRESSURE
BUILDS IN BEHIND THE FRONT.
WITH GUSTY SOUTH WINDS MONDAY...A SMALL CRAFT ADVISORY HAS BEEN
ISSUED FOR THE ILLINOIS AND INDIANA NEAR SHORE WATERS FROM
MID-MORNING THROUGH MORNING EVENING.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...10 AM MONDAY TO 10 PM MONDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1243 PM CDT Sun Aug 31 2014
.UPDATE...
ISSUED AT 948 AM CDT SUN AUG 31 2014
A low overcast persists across much of central Illinois along and
east of a Peoria to Jacksonville line this morning. 1430z visible
satellite imagery is showing thin spots developing in the cloud
cover, so am expecting it to dissipate within the next 2 to 3
hours. HRRR ceiling forecast shows this trend quite nicely,
resulting in a partly to mostly sunny afternoon. May see a few
showers/thunder pop up along/south of I-70: however, areal
coverage will remain spotty. Updated the forecast to better
reflect sky cover trends this morning and to confine PoPs to just
the far SE KILX CWA.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 358 AM CDT SUN AUG 31 2014
Shortwave trough and jet entrance region that brought banded
convection and some locally heavy precipitation to central IL last
evening has shifted northeastward with shower activity nearly ended
over the ILX CWA. With clearing skies and good radiational cooling,
patchy fog will continue to form overnight, mainly I-55
westward.
Moist conditions with enough instability will remain through the
afternoon today for a few showers and thunderstorms, mainly I-70
southeastward, but a relatively dry day expected. Highs in the mid
80s are expected.
After sunset, convection should end quickly across the CWA with the
loss of surface heating. Late in the night, chances for
thunderstorms will spread back into west central Illinois as another
cold front approaches from the west.
&&
.LONG TERM...(Monday through Saturday)
ISSUED AT 358 AM CDT SUN AUG 31 2014
SPC continues a slight risk (15+%) of severe thunderstorms across
central IL nw of a Flora to Robinson line Monday afternoon/evening
for damaging winds and large hail. This seems reasonable considering
surface to 6 km bulk shear values of 30-40 kts, CAPES of 2-3k J/kg.
Heavy rains also possible with thunderstorms in tropical airmass
ahead of frontal boundary. Short waves and 30-40 kt low level jet
moving into IL river valley later Sunday night into Monday morning
and then spreading into eastern IL Monday afternoon/evening. Upper
level trof over northern Rockies moves east into Midwest
Monday/Monday night and drives a cold front southeast across central
IL Monday night. Continued likely pops across much of area Monday
afternoon into Monday night, though diminishing pops overnight
Monday night nw of IL river. Best chances of showers and
thunderstorms lingers over areas from I-72 south on Tue especially
in the morning. The 5% risk of severe storms Tue is southeast of
Lawrenceville. Quite warm and humid Monday ahead of front with highs
82-88F and dewpoints 70-75F and warmest temps in southeast IL where
rain arrives later.
Frontal boundary to weaken as it moves se into Ohio River valley
Tue/Wed with near zonal upper level flow over the region. Carried
just slight chance of convection during midweek from Tue night
through Thu night. Highs in the low to mid 80s Tue/Wed climb into
mid 80s to around 90F Thu/Fri as dewpoints rise back into the low to
mid 70s with heat indices approaching 100F southern counties Thu/Fri
afternoon. Next frontal boundary press southeast into IL Friday
afternoon into Sat and bringing next best chances of showers and
thunderstorms and cooler temps during next weekend.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1243 PM CDT SUN AUG 31 2014
MVFR ceilings will persist at the central Illinois terminals for
the next hour or two before gradually dissipating as the afternoon
progresses. Based on satellite trends, have scattered ceilings at
most sites by 19z, then at KDEC and KBMI by 20z. After that,
mostly clear skies will prevail through the evening before clouds
begin to increase from the west late tonight. A thunderstorm
complex currently developing across western Iowa/Nebraska will
track eastward tonight, with most model guidance keeping it west
of the Illinois River until 12z. Think storms will arrive in the
Illinois River Valley toward dawn in a weakening state, then
spread eastward across the area Monday morning. Have therefore
introduced low VFR ceilings and VCTS at KPIA after 12z, then
further east to KBMI and KDEC after 14/15z. Given plenty of
low-level moisture and relatively light winds, included slightly
reduced visbys down to 4sm at KCMI where skies will remain mostly
clear through dawn. Further west, think increasing clouds and wind
will prevent fog formation.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARNES
SHORT TERM...ONTON
LONG TERM...07
AVIATION...BARNES
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1108 AM CDT SUN AUG 31 2014
.DISCUSSION...
328 AM CDT
AFTER A FAIRLY QUIET DAY ACROSS THE AREA TODAY...ATTENTION QUICKLY
SHIFTS TO THE WEATHER FOR LABOR DAY INTO MONDAY NIGHT...DURING WHICH
PERIODS OF EXTREMELY HEAVY RAINFALL AND SEVERE WEATHER ARE POSSIBLE.
THUNDERSTORMS CONTINUED TO TRAIN ACROSS THE SAME AREAS ACROSS
PORTIONS OF FORD AND IROQUOIS COUNTIES IN ILLINOIS AND ALSO BENTON
COUNTY IN INDIANA YESTERDAY EVENING AND INTO THE OVERNIGHT HOURS.
THESE AREAS LIED IN THE RIGHT ENTRANCE REGION OF AN UPPER LEVEL JET
STREAK. THE COMBINATION OF THIS...AND THE CONTINUED LOW LEVEL
CONFLUENCE CONTINUED TO DRIVE THIS CONVECTION. RADAR ESTIMATES SOME
VERY HEFTY ISOLATED RAINFALL AMOUNTS IN EXCESS OF 4 INCHES ACROSS
PORTIONS OF THESE COUNTIES. ALTHOUGH SOME ISOLATED ACTIVITY
CONTINUES ACROSS THIS AREA AS OF THIS WRITING...IT IS EXPECTED THAT
ALL THIS ACTIVITY WILL SHIFT OUT OF THE AREA AROUND...OR JUST PRIOR
TO DAYBREAK AS THE UPPER LEVEL JET DEVELOPS EASTWARD.
WATER VAPOR IMAGERY EARLY THIS MORNING SHOWS THE NEXT UPPER LEVEL
SYSTEM CURRENTLY DIGGING ACROSS THE ROCKIES. AIRCRAFT AND UPPER AIR
OBSERVATIONS ACROSS WESTERN CANADA AND OVER THE NORTHEAST PACIFIC
INDICATE SOME IMPRESSIVE UPPER LEVEL WINDS...FOR THIS TIME OF
YEAR...IN EXCESS OF 110 KT WITHIN THE CORE OF THE JET STREAK
DIGGING OVER THE WESTERN CONUS. THE FIRST MID LEVEL IMPULSE IS
EXPECTED TO CONTINUE SHIFTING EASTWARD OVER THE UPPER MIDWEST INTO
MONDAY MORNING. AS IT DOES SO...IT WILL DRIVE A FAIRLY STOUT
SURFACE LOW NORTHEASTWARD FROM THE DAKOTAS TO ONTARIO. SOME VERY
SUBSTANTIAL CONVECTION IS EXPECTED TO DEVELOP AHEAD OF THE COLD
FRONT LATER TODAY ACROSS PORTIONS OF THE MID MISSOURI VALLEY AND
INTO MINNESOTA. THIS ACTIVITY WILL LIKELY SHIFT EAST-NORTHEASTWARD
OVERNIGHT TONIGHT...WITH SOME OF THE REMNANT ACTIVITY POSSIBLY
REACHING NORTH CENTRAL ILLINOIS BY AROUND...OR JUST PRIOR TO
DAYBREAK MONDAY. IT APPEARS THAT THIS INITIAL ROUND OF CONVECTION
COULD BE IN A WEAKENING PHASE AS IT TRIES TO PUSH OVER PORTIONS
OF NORTHERN ILLINOIS MONDAY MORNING. HOWEVER...RENEWED CONVECTIVE
DEVELOPMENT...POSSIBLY ALONG ANY OUTFLOW BOUNDARIES LAID DOWN BY
EARLY MORNING ACTIVITY...IS LIKELY ACROSS PORTIONS OF NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA BY MONDAY AFTERNOON.
MODEL SOUNDINGS ALL INDICATE FAVORABLE PROFILES FOR ACTIVE STRONG TO
SEVERE STORMS OVER THE AREA DURING THE AFTERNOON AND EARLY EVENING
MONDAY. DEEP LAYER BULK SHEAR LOOKS TO BE SOMEWHAT
UNIDIRECTIONAL...BUT WITH 0-6 KM SPEED SHEAR OF NEARLY 50
KT...ORGANIZED CONVECTIVE ACTIVITY APPEARS VERY POSSIBLE. THE MAIN
COMPLICATING FACTOR AT THIS POINT IS HOW MUCH ANY CLOUD DEBRIS OR
REMNANT MORNING CONVECTIVE ACTIVITY IMPACTS AFTERNOON HEATING AND
DESTABILIZATION ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN
INDIANA. HOWEVER...IN SPITE OF THIS POSSIBILITY EARLY IN THE
DAY...IT DOES APPEAR THAT THE HIGH THETA E NEAR SURFACE AIR MASS
SHOULD BE ENOUGH TO PRODUCE AMPLE MLCAPE VALUES AT OR JUST IN
EXCESS OF 1500 J/KG...WHICH COMBINED WITH THE 45+ DEEP LAYER SHEAR
CERTAINLY POINTS TO A SEVERE THREAT. AT THIS TIME IT APPEARS
RATHER MODEST MID LEVEL LAPSE RATES WOULD RESULT IN THE MAIN
SEVERE THREAT BEING STRONG DAMAGING WIND GUSTS. HOWEVER...THERE IS
ALSO A SECONDARY THREAT OF LARGE HAIL...ESPECIALLY IF ANY SUPER
CELLS CAN FORM.
THERE IS ALSO A DECENT CONCERN FOR EXTREMELY HEAVY RAINFALL RATES
WITH THESE STORMS...WITH PWAT VALUES IN THIS JUICY ENVIRONMENT
LIKELY TO RESIDE AROUND 1.7 INCHES. NUMERICAL GUIDANCE CONTINUES TO
SUGGEST THAT A SECONDARY MID LEVEL IMPULSE WILL APPROACH THE AREA
MONDAY NIGHT AND ACT TO INDUCE/STRENGTHEN A SOUTHWESTERLY UPPER
LEVEL JET STREAK ACROSS THE GREAT LAKES REGION INTO MONDAY NIGHT.
THIS PROCESS COULD SET UP PORTIONS OF THE AREA WITHIN THE FAVORABLE
RIGHT ENTRANCE REGION OF A 100 KT UPPER LEVEL JET INTO TUESDAY
MORNING AS THE SURFACE COLD FRONTAL BOUNDARY SLOWLY TRIES TO SHIFT
SOUTHWARD ACROSS THE SOUTHERN HALF OF MY CWA. I HAVE INCREASING
CONCERNS THAT THIS COULD SET UP A VERY HEAVY RAIN EVENT MONDAY
NIGHT...WITH STORMS POTENTIALLY TRAINING TO THE EAST NORTHEAST
NEARLY PARALLEL TO THE SURFACE BOUNDARY. AT THIS TIME IT APPEARS THIS
HEAVY RAIN THREAT COULD END UP SOUTH OF INTERSTATE 80 MONDAY NIGHT.
HOWEVER...UNCERTAINTY IS STILL A BIT HIGH AS TO HOW FAR SOUTH THE
SURFACE FRONT WILL GET MONDAY NIGHT...AND HENCE WHERE THE MOST
FAVORED AREAS FOR TRAINING CELLS WILL OCCUR. AT THIS POINT...I HAVE
ADDED HEAVY RAIN WORDING TO THE FORECAST...MAINLY FOR AREAS SOUTH OF
INTERSTATE 80 INTO MONDAY NIGHT.
FOLLOWING THIS ACTIVE WEATHER MONDAY NIGHT IT APPEARS THE WEATHER
WILL BE DRY FOR THE MOST PART THROUGH LATE WEEK. THE MAIN STORY
HOWEVER...WILL BE THE INCREASING HEAT BY THURSDAY. FORECAST GUIDANCE
CONTINUES TO FORECAST MID LEVEL HEIGHTS TO BUILD SUBSTANTIALLY
ACROSS THE CENTRAL CONUS. THIS COULD LEAD TO A RUN AT
90 TEMPERATURES FOR THURSDAY AS 850 MB TEMPERATURES WARM TO 20 TO
22C. I HAVE STARTED CUTTING BACK ON THE SLIGHT CHANCE
POPS...ESPECIALLY ON WEDNESDAY AND WEDNESDAY NIGHT...BUT LEFT IN
SOME SLIGHTS FOR THURSDAY. ALTHOUGH SOME ISOLATED CONVECTIVE
ACTIVITY IS POSSIBLE DURING THIS TIME...IT APPEARS THAT THE BUILDING
HEIGHTS AND WARMING TEMPS ALOFT COULD END UP CAPPING THE AREA...AND
LIMITING THE THREAT FOR CONVECTIVE DEVELOPMENT THROUGH THURSDAY.
CONVECTIVE CHANCES DO LOOK TO RETURN TO THE AREA AGAIN BY FRIDAY.
ANOTHER SIGNIFICANT WAVE IS EXPECTED TO SHIFT EASTWARD ACROSS THE
NORTHERN CONUS AND SOUTHERN CANADA LATE IN THE PERIOD...AND THIS
LOOKS TO SHIFT A COLD FRONT SOUTHWARD ACROSS THE AREA SOMETIME
EITHER FRIDAY OR FRIDAY NIGHT AND THIS COULD SPARK OFF ACTIVITY
ACROSS THE AREA. COOLER WEATHER DOES LOOK TO OVERSPREAD TO AREA
UNDER NORTHERLY WINDS BY EARLY NEXT WEEKEND.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CHANCE FOR A LAKE BREEZE/WIND SHIFT TO EASTERLY LATE SUNDAY
AFTERNOON.
KREIN/BMD
//DISCUSSION...UPDATED 12Z...
AS THE CLOUD SHIELD CLEARS OUT AND WITH CALM WINDS AND RESIDUAL
LOW LEVEL MOISTURE IN PLACE...SOME PATCHY FOG/STRATUS HAS
DEVELOPED. HOWEVER...WITH AMPLE SUNSHINE...EXPECT THAT THE
FOG/STRATUS WILL QUICKLY DISSIPATE BY MID MORNING WITH VFR
CONDITIONS EXPECTED THE REMAINDER OF THE DAY. WINDS SHOULD REMAIN
LIGHT ENOUGH TO ALLOW A LAKE BREEZE TO DEVELOP...BUT THERE APPEARS
TO BE LITTLE PUSH BEHIND THE BOUNDARY...SO AT THIS POINT...FEEL
THAT CHANCES ARE LOW THAT THE LAKE BREEZE WILL PUSH INLAND OF
ORD/MDW. HOWEVER...IF THE LAKE BREEZE DOES MANAGE TO PUSH WEST OF
ORD/MDW...IT WOULD NOT BE UNTIL ARND 22-23Z AND ELY WINDS WOULD BE
ARND 5-7KT. ANOTHER APPROACHING COLD FRONT WILL BRING INCREASING
CHANCES FOR MORE SHOWERS AND THUNDERSTORMS BUT THIS WILL LIKELY
NOT BE UNTIL AFTER 12Z TOMORROW.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE IN LAKE BREEZE SUNDAY AFTERNOON...AND
MEDIUM CONFIDENCE THAT THE BOUNDARY WILL NOT PUSH THROUGH
ORD/MDW.
* LOW CONFIDENCE IN TIMING TS TOMORROW.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...CHANCE SHRA/TSRA.
TUESDAY AND WEDNESDAY...VFR. WX NIL.
THURSDAY THROUGH SATURDAY...PERIODIC CHANCES FOR SHRA/TSRA.
KREIN
&&
.MARINE...
300 AM CDT
A PERIOD OF CHANGEABLE WEATHER...IN PARTICULAR...WIND
DIRECTION...IS SETTING UP FOR THE NEXT SEVERAL DAYS. LOW PRESSURE
JUST NORTH OF GEORGIAN BAY WILL TRACK EAST TO SOUTHERN QUEBEC BY
LATE SUNDAY MORNING WHILE DRAGGING A WEAK COLD FRONT SOUTH ACROSS
THE LAKE AND CLEARING THE SOUTH END OF LAKE MICHIGAN BY EARLY
SUNDAY. THIS WILL SET UP A BRIEF PERIOD OF NWLY WINDS...BUT AS
HIGH PRESSURE BUILDS OVER THE NORTHERN LAKES BEHIND THE FRONT
SUNDAY AFTERNOON WINDS WILL BECOME LGT/VRBL FOR A SHORT TIME.
SLY FLOW WILL RETURN TO THE LAKE SUNDAY NIGHT AND
MONDAY...STRENGTHENING TO ARND 25KT AS ANOTHER LOW DEVELOPING OVER
THE NORTHERN PLAINS DEEPENS WHILE TRACKING TO HUDSON BAY MONDAY
NIGHT. THIS LOW WILL DRAG ANOTHER COLD FRONT SOUTH ACROSS LAKE
MICHIGAN MONDAY NIGHT. WEAK HIGH PRESSURE WILL BUILD ACROSS THE
LAKE TUESDAY BRINGING ANOTHER PERIOD OF LIGHT WINDS. BUT YET
ANOTHER LOW IS EXPECTED TO MOVE OUT OF THE NORTHERN ROCKIES AND
INTO THE NORTHERN PLAINS WEDNESDAY NIGHT...BRINGING ANOTHER PERIOD
OF BRISK SOUTH WINDS TO THE LAKE FOR WEDNESDAY AND THURSDAY. THIS
LOW IS FORECAST TO TRACK TO NEAR THE SOUTHERN TIP OF JAMES BAY
DRAGGING ANOTHER COLD FRONT ACROSS THE LAKE FRIDAY OR FRIDAY
NIGHT. ACCOMPANYING THESE FRONTAL PASSAGES WILL ALSO BE PERIODS OF
THUNDERSTORMS AS WELL.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
948 AM CDT Sun Aug 31 2014
.UPDATE...
ISSUED AT 948 AM CDT SUN AUG 31 2014
A low overcast persists across much of central Illinois along and
east of a Peoria to Jacksonville line this morning. 1430z visible
satellite imagery is showing thin spots developing in the cloud
cover, so am expecting it to dissipate within the next 2 to 3
hours. HRRR ceiling forecast shows this trend quite nicely,
resulting in a partly to mostly sunny afternoon. May see a few
showers/thunder pop up along/south of I-70: however, areal
coverage will remain spotty. Updated the forecast to better
reflect sky cover trends this morning and to confine PoPs to just
the far SE KILX CWA.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 358 AM CDT SUN AUG 31 2014
Shortwave trough and jet entrance region that brought banded
convection and some locally heavy precipitation to central IL last
evening has shifted northeastward with shower activity nearly ended
over the ILX CWA. With clearing skies and good radiational cooling,
patchy fog will continue to form overnight, mainly I-55
westward.
Moist conditions with enough instability will remain through the
afternoon today for a few showers and thunderstorms, mainly I-70
southeastward, but a relatively dry day expected. Highs in the mid
80s are expected.
After sunset, convection should end quickly across the CWA with the
loss of surface heating. Late in the night, chances for
thunderstorms will spread back into west central Illinois as another
cold front approaches from the west.
&&
.LONG TERM...(Monday through Saturday)
ISSUED AT 358 AM CDT SUN AUG 31 2014
SPC continues a slight risk (15+%) of severe thunderstorms across
central IL nw of a Flora to Robinson line Monday afternoon/evening
for damaging winds and large hail. This seems reasonable considering
surface to 6 km bulk shear values of 30-40 kts, CAPES of 2-3k J/kg.
Heavy rains also possible with thunderstorms in tropical airmass
ahead of frontal boundary. Short waves and 30-40 kt low level jet
moving into IL river valley later Sunday night into Monday morning
and then spreading into eastern IL Monday afternoon/evening. Upper
level trof over northern Rockies moves east into Midwest
Monday/Monday night and drives a cold front southeast across central
IL Monday night. Continued likely pops across much of area Monday
afternoon into Monday night, though diminishing pops overnight
Monday night nw of IL river. Best chances of showers and
thunderstorms lingers over areas from I-72 south on Tue especially
in the morning. The 5% risk of severe storms Tue is southeast of
Lawrenceville. Quite warm and humid Monday ahead of front with highs
82-88F and dewpoints 70-75F and warmest temps in southeast IL where
rain arrives later.
Frontal boundary to weaken as it moves se into Ohio River valley
Tue/Wed with near zonal upper level flow over the region. Carried
just slight chance of convection during midweek from Tue night
through Thu night. Highs in the low to mid 80s Tue/Wed climb into
mid 80s to around 90F Thu/Fri as dewpoints rise back into the low to
mid 70s with heat indices approaching 100F southern counties Thu/Fri
afternoon. Next frontal boundary press southeast into IL Friday
afternoon into Sat and bringing next best chances of showers and
thunderstorms and cooler temps during next weekend.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 656 AM CDT SUN AUG 31 2014
Mainly IFR/MVFR visibilities this morning due to low ceilings and
areas of fog. Expect improving conditions through 14Z with
conditions generally becoming VFR as surface heating lifts
ceilings and dissipates fog. Isold TSRA to continue until around
00Z mainly K1H2-KPRG southward with potential MVFR cig/vsby and
gusty winds. After 00Z...TSRA ending with VFR conditions across
central/SE Illinois. Toward 12Z Monday...potential TSRA
development KIJX-KPIA westward depending on speed of approaching
system, but probability of TSRA and associated flight category
reductions too low probability before 12Z for mention in TAFS at
this time.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARNES
SHORT TERM...ONTON
LONG TERM...07
AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
303 AM CDT SUN AUG 31 2014
.DISCUSSION...
221 PM CDT
SYNOPSIS...SCATTERED THUNDERSTORMS ARE POSSIBLE NW OF I-55 WHILE A
LINE OF STORMS WILL IMPACT AREAS ALONG AND EAST OF I-55 THROUGH THIS
EVENING. TOMORROW WILL BE DRY BUT UNSETTLED WEATHER RETURNS MONDAY
WITH MULTIPLE CHANCES FOR THUNDERSTORMS. SEVERE STORMS ARE POSSIBLE
MONDAY. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE PERIOD WITH A
COUPLE DAYS GETTING INTO THE MID 80S.
THROUGH TONIGHT...
AN UPPER LEVEL TROUGH IS OVER THE UPPER MISSISSIPPI RIVER VALLEY AND
IT WILL PASS OVER THE REGION THROUGH THIS EVENING. A SURFACE LOW IS
OVER THE NORTHERN END OF LAKE MI WITH ITS COLD FRONT EXTENDING
THROUGH WI AND EASTERN IA. THE LOW WILL CONTINUE NE THROUGH THE
NIGHT.
HAVE MUCH HIGHER CONFIDENCE IN THE CONVECTIVE FORECAST TODAY
COMPARED TO YESTERDAY DUE TO CLEAR FORCING MECHANISMS. EXPECTING TO
HAVE TWO AREAS TO MONITOR. THE FIRST IS NORTHWEST OF I-55 WHERE
ISOLATED TO SCATTERED STORMS WILL CONTINUE TO FESTER THROUGH THIS
AFTERNOON AHEAD OF UPPER LEVEL WAVE AND COLD FRONT.
THE BIGGER CONCERN WILL BE ALONG AND SE OF I-55 WHERE A LINE OF
SHOWERS AND STORMS HAS ALREADY DEVELOPED. THE LATEST RAP ANALYSIS
SHOWS A NICE CORRIDOR OF MOISTURE CONVERGENCE WHERE THE CONVECTION
HAS FIRED. THE LATEST AMDAR SOUNDINGS ARE CAPLESS WITH 1000-1500
J/KG OF CAPE. HOWEVER...LAPSE RATES ARE POOR AND WIND SHEAR IS
MINIMAL AT BEST. THE AMDAR SOUNDINGS DO HAVE LOW LEVEL INVERTED
V/S AND THE RAP ANALYSIS HAS AROUND 1000 J/KG OF DOWNDRAFT CAPE.
THEREFORE NOT EXPECTING WIDESPREAD SEVERE WEATHER...BUT A STORM OR
TWO MAY PULSE UP AND PRODUCE SEVERE WINDS.
HEAVY DOWNPOURS ARE ALSO EXPECTED WITH PWAT VALUES OF 1.6-1.8
INCHES. BASED ON SHORT TERM GUIDANCE...THE AREA MOST CONCERNING IS
SOUTH OF A VALPARAISO IN TO GIBSON CITY IL LINE. STORMS WILL
CONTINUE TO DEVELOP AND MOVE OVER THIS REGION WITH AMPLE FORCING.
THEREFORE IF STORMS TRAIN OVER THE SAME AREA FOR AN EXTENDED PERIOD
OF TIME...FLASH FLOODING MAY OCCUR.
STORMS DIMINISH AND PUSH EAST OVERNIGHT WHILE HIGH PRESSURE SPREADS
OVER THE REGION. WINDS WILL DIMINISH AND FOG IS POSSIBLE.
SUNDAY...
SUNDAY LOOKS DRY WITH HIGH PRESSURE OVER THE REGION. WE WILL BE IN
THE NEXT LOW/S WARM SECTOR WITH 850MB TEMPS AROUND 18C. THEREFORE
RAISED HIGH TEMPS INTO THE MID 80S AWAY FROM THE LAKE. THE WEAK
PRESSURE GRADIENT WILL ALLOW A LAKE BREEZE TO FORM AND KEEP THE IL
LAKEFRONT AROUND 80. GUIDANCE HAS SLOWED THE NEXT LOW SO PUSHED
BACK POPS SUNDAY NIGHT.
JEE
MONDAY...
UPPER WAVE DIGGING TOWARDS THE INTER-MOUNTAIN WEST THIS AFTERNOON
WILL LIFT ACROSS THE PLAINS INTO THE UPPER MIDWEST ON MONDAY WITH
ATTENDANT SURFACE LOW DEEPENING AS IT LIFTS ACROSS ONTARIO TO NEAR
JAMES BAY BY LATE MONDAY. A SURFACE FRONT WILL SLOWLY PUSH ACROSS
THE REGION MONDAY AND GUIDANCE HAS TRENDED TOWARDS A SLOWER SOLUTION
OVER THE LAST 24 HOURS. MODERATE TO STRONG INSTABILITY IS PROGGED TO
DEVELOP ALONG AND AHEAD OF THE FRONT WHERE THE GFS ADVERTISES A
CORRIDOR OF JUST OVER 2000 J/KG MLCAPE JUST TO THE WEST OF THE CWA
MONDAY AFTERNOON. THE BETTER CONVERGENCE ASSOCIATED WITH THE COLD
FRONT MAY ARRIVE JUST PAST THE MOST FAVORABLE DIURNAL TIMING IF
TIMING TRENDS HOLD TRUE...BUT THE RIGHT ENTRANCE REGION TO THE UPPER
JET IS PROGGED TO MOVE OVER THE AREA BY MID TO LATE IN THE EVENING
WITH DEEP LAYER SHEAR VALUES INCREASING TO AROUND 40 KT OR SO WHICH
WOULD BE SUFFICIENT FOR AN ORGANIZED SEVERE WEATHER THREAT...THOUGH
THIS THREAT SHOULD DIMINISH WEST TO EAST AS WE GET LATER INTO THE
OVERNIGHT HOURS AND THE BOUNDARY LAYER STABILIZES.
TUESDAY THROUGH THURSDAY...
A SECONDARY SHORTWAVE TROUGH IS PROGGED TO PUSH ACROSS THE REGION ON
TUESDAY BRINGING ADDITIONAL CHANCES FOR SHOWER AND THUNDERSTORMS
MAINLY ACROSS SOUTH/SOUTHEASTERN PORTIONS OF THE CWA WHERE THE
FRONTAL BOUNDARY MAY STILL SLOWLY BE MAKING A PUSH. MODERATE TO
STRONG HEIGHTS RISES QUICKLY BUILD IN BEHIND THIS FEATURE THOUGH AND
SHOULD RESULT IN A DRY WEATHER FOR MOST OF THE FORECAST AREA
TUESDAY. THE GFS IS PARTICULAR IS HOLDING ONTO SOME POPS NORTH OF
THE BOUNDARY WEDNESDAY INTO THURSDAY WHERE PERSISTENT WARM ADVECTION
WILL RESULT IN MID LEVEL ASCENT...THOUGH THE ECMWF REMAINS DRY THIS
PERIOD. WILL MAINTAIN SLIGHT CHANCE POPS IN THE MEANTIME.
FRIDAY THROUGH SATURDAY...
THERMAL RIDGE IS EXPECTED TO MOVE BACK OVERHEAD LATE IN THE WEEK
WITH H85 TEMPS PUSHING INTO THE LOW 20C RANGE WHICH WILL LEAD TO
ANOTHER WARM UP WITH TEMPS INTO THE UPPER 80S. ANOTHER SLOW MOVING
COLD FRONT WILL THEN SAG SOUTH ACROSS THE REGION BRINGING RENEWED
CHANCES FOR SHOWERS AND THUNDERSTORMS.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SLIGHT CHANCE OF FOG/STRATUS EARLY SUNDAY MORNING.
* CHANCE FOR A LAKE BREEZE/WIND SHIFT TO EASTERLY LATE SUNDAY
AFTERNOON.
KREIN
//DISCUSSION...UPDATED 06Z...
SCT TSRA WILL CONTINUE TONIGHT WELL TO THE SOUTHEAST OF THE
TERMINALS OVER EAST CENTRAL IL AND WEST CENTRAL INDIANA. AN OLD
BOUNDARY LIES JUST SOUTH OF THE TERMINALS WITH SLIGHTLY DRIER/LESS
HUMID AIR TO THE NORTH...MOSTLY NOTABLE IN THE DEWPOINT GRADIENT.
GIVEN THE LACK OF RAIN TODAY AND MIXING OUT OF LOW LEVEL
MOISTURE...PLUS THE URBAN HEAT ISLAND EFFECTS...NOT ANTICIPATING
FOG/STRATUS TO BE MUCH OF AN ISSUE FOR THE CHICAGO TERMINALS.
HOWEVER...SHORT RANGE MODEL GUIDANCE IS STILL INDICATING A HIGH
POSSIBILITY OF IFR CIGS/VSBY AWAY FROM THE HIGHLY URBANIZED
AREAS...SO WILL MAINTAIN MVFR/IFR FOG AT THE MORE FOG PRONE
OUTLYING TERMINALS...PARTICULARLY GYY/DPA/RFD. ANY VSBY
RESTRICTIONS THAT DO FORM OVERNIGHT WILL QUICKLY DISSIPATE BY MID
MORNING SUNDAY WITH VFR CONDITIONS EXPECTED THE REMAINDER OF THE
DAY. WINDS SHOULD REMAIN LIGHT ENOUGH TO ALLOW A LAKE BREEZE TO
DEVELOP...BUT THERE APPEARS TO BE LITTLE PUSH BEHIND THE
BOUNDARY...SO AT THIS POINT...FEEL THAT CHANCES ARE LOW THAT THE
LAKE BREEZE WILL PUSH INLAND OF ORD/MDW. HOWEVER...IF THE LAKE
BREEZE DOES MANAGE TO PUSH WEST OF ORD/MDW...IT WOULD NOT BE UNTIL
ARND 22-23Z AND ELY WINDS WOULD BE ARND 5-7KT.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH CONFIDENCE IN NO IFR AT ORD/MDW OVERNIGHT.
* MEDIUM TO HIGH CONFIDENCE IN LAKE BREEZE SUNDAY AFTERNOON...AND
MEDIUM CONFIDENCE THAT THE BOUNDARY WILL NOT PUSH THROUGH
ORD/MDW.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...PERIOD OR TWO OF SHRA/TSRA...STRONG TSRA POSSIBLE.
TUESDAY AND WEDNESDAY...PREDOMINANTLY VFR.
THURSDAY...SLIGHT CHANCE TSRA...OTHERWISE VFR.
FRIDAY...CHANCE TSRA.
IZZI
&&
.MARINE...
300 AM CDT
A PERIOD OF CHANGEABLE WEATHER...IN PARTICULAR...WIND
DIRECTION...IS SETTING UP FOR THE NEXT SEVERAL DAYS. LOW PRESSURE
JUST NORTH OF GEORGIAN BAY WILL TRACK EAST TO SOUTHERN QUEBEC BY
LATE SUNDAY MORNING WHILE DRAGGING A WEAK COLD FRONT SOUTH ACROSS
THE LAKE AND CLEARING THE SOUTH END OF LAKE MICHIGAN BY EARLY
SUNDAY. THIS WILL SET UP A BRIEF PERIOD OF NWLY WINDS...BUT AS
HIGH PRESSURE BUILDS OVER THE NORTHERN LAKES BEHIND THE FRONT
SUNDAY AFTERNOON WINDS WILL BECOME LGT/VRBL FOR A SHORT TIME.
SLY FLOW WILL RETURN TO THE LAKE SUNDAY NIGHT AND
MONDAY...STRENGTHENING TO ARND 25KT AS ANOTHER LOW DEVELOPING OVER
THE NORTHERN PLAINS DEEPENS WHILE TRACKING TO HUDSON BAY MONDAY
NIGHT. THIS LOW WILL DRAG ANOTHER COLD FRONT SOUTH ACROSS LAKE
MICHIGAN MONDAY NIGHT. WEAK HIGH PRESSURE WILL BUILD ACROSS THE
LAKE TUESDAY BRINGING ANOTHER PERIOD OF LIGHT WINDS. BUT YET
ANOTHER LOW IS EXPECTED TO MOVE OUT OF THE NORTHERN ROCKIES AND
INTO THE NORTHERN PLAINS WEDNESDAY NIGHT...BRINGING ANOTHER PERIOD
OF BRISK SOUTH WINDS TO THE LAKE FOR WEDNESDAY AND THURSDAY. THIS
LOW IS FORECAST TO TRACK TO NEAR THE SOUTHERN TIP OF JAMES BAY
DRAGGING ANOTHER COLD FRONT ACROSS THE LAKE FRIDAY OR FRIDAY
NIGHT. ACCOMPANYING THESE FRONTAL PASSAGES WILL ALSO BE PERIODS OF
THUNDERSTORMS AS WELL.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
102 AM CDT SUN AUG 31 2014
.DISCUSSION...
221 PM CDT
SYNOPSIS...SCATTERED THUNDERSTORMS ARE POSSIBLE NW OF I-55 WHILE A
LINE OF STORMS WILL IMPACT AREAS ALONG AND EAST OF I-55 THROUGH THIS
EVENING. TOMORROW WILL BE DRY BUT UNSETTLED WEATHER RETURNS MONDAY
WITH MULTIPLE CHANCES FOR THUNDERSTORMS. SEVERE STORMS ARE POSSIBLE
MONDAY. TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE PERIOD WITH A
COUPLE DAYS GETTING INTO THE MID 80S.
THROUGH TONIGHT...
AN UPPER LEVEL TROUGH IS OVER THE UPPER MISSISSIPPI RIVER VALLEY AND
IT WILL PASS OVER THE REGION THROUGH THIS EVENING. A SURFACE LOW IS
OVER THE NORTHERN END OF LAKE MI WITH ITS COLD FRONT EXTENDING
THROUGH WI AND EASTERN IA. THE LOW WILL CONTINUE NE THROUGH THE
NIGHT.
HAVE MUCH HIGHER CONFIDENCE IN THE CONVECTIVE FORECAST TODAY
COMPARED TO YESTERDAY DUE TO CLEAR FORCING MECHANISMS. EXPECTING TO
HAVE TWO AREAS TO MONITOR. THE FIRST IS NORTHWEST OF I-55 WHERE
ISOLATED TO SCATTERED STORMS WILL CONTINUE TO FESTER THROUGH THIS
AFTERNOON AHEAD OF UPPER LEVEL WAVE AND COLD FRONT.
THE BIGGER CONCERN WILL BE ALONG AND SE OF I-55 WHERE A LINE OF
SHOWERS AND STORMS HAS ALREADY DEVELOPED. THE LATEST RAP ANALYSIS
SHOWS A NICE CORRIDOR OF MOISTURE CONVERGENCE WHERE THE CONVECTION
HAS FIRED. THE LATEST AMDAR SOUNDINGS ARE CAPLESS WITH 1000-1500
J/KG OF CAPE. HOWEVER...LAPSE RATES ARE POOR AND WIND SHEAR IS
MINIMAL AT BEST. THE AMDAR SOUNDINGS DO HAVE LOW LEVEL INVERTED
V/S AND THE RAP ANALYSIS HAS AROUND 1000 J/KG OF DOWNDRAFT CAPE.
THEREFORE NOT EXPECTING WIDESPREAD SEVERE WEATHER...BUT A STORM OR
TWO MAY PULSE UP AND PRODUCE SEVERE WINDS.
HEAVY DOWNPOURS ARE ALSO EXPECTED WITH PWAT VALUES OF 1.6-1.8
INCHES. BASED ON SHORT TERM GUIDANCE...THE AREA MOST CONCERNING IS
SOUTH OF A VALPARAISO IN TO GIBSON CITY IL LINE. STORMS WILL
CONTINUE TO DEVELOP AND MOVE OVER THIS REGION WITH AMPLE FORCING.
THEREFORE IF STORMS TRAIN OVER THE SAME AREA FOR AN EXTENDED PERIOD
OF TIME...FLASH FLOODING MAY OCCUR.
STORMS DIMINISH AND PUSH EAST OVERNIGHT WHILE HIGH PRESSURE SPREADS
OVER THE REGION. WINDS WILL DIMINISH AND FOG IS POSSIBLE.
SUNDAY...
SUNDAY LOOKS DRY WITH HIGH PRESSURE OVER THE REGION. WE WILL BE IN
THE NEXT LOW/S WARM SECTOR WITH 850MB TEMPS AROUND 18C. THEREFORE
RAISED HIGH TEMPS INTO THE MID 80S AWAY FROM THE LAKE. THE WEAK
PRESSURE GRADIENT WILL ALLOW A LAKE BREEZE TO FORM AND KEEP THE IL
LAKEFRONT AROUND 80. GUIDANCE HAS SLOWED THE NEXT LOW SO PUSHED
BACK POPS SUNDAY NIGHT.
JEE
MONDAY...
UPPER WAVE DIGGING TOWARDS THE INTER-MOUNTAIN WEST THIS AFTERNOON
WILL LIFT ACROSS THE PLAINS INTO THE UPPER MIDWEST ON MONDAY WITH
ATTENDANT SURFACE LOW DEEPENING AS IT LIFTS ACROSS ONTARIO TO NEAR
JAMES BAY BY LATE MONDAY. A SURFACE FRONT WILL SLOWLY PUSH ACROSS
THE REGION MONDAY AND GUIDANCE HAS TRENDED TOWARDS A SLOWER SOLUTION
OVER THE LAST 24 HOURS. MODERATE TO STRONG INSTABILITY IS PROGGED TO
DEVELOP ALONG AND AHEAD OF THE FRONT WHERE THE GFS ADVERTISES A
CORRIDOR OF JUST OVER 2000 J/KG MLCAPE JUST TO THE WEST OF THE CWA
MONDAY AFTERNOON. THE BETTER CONVERGENCE ASSOCIATED WITH THE COLD
FRONT MAY ARRIVE JUST PAST THE MOST FAVORABLE DIURNAL TIMING IF
TIMING TRENDS HOLD TRUE...BUT THE RIGHT ENTRANCE REGION TO THE UPPER
JET IS PROGGED TO MOVE OVER THE AREA BY MID TO LATE IN THE EVENING
WITH DEEP LAYER SHEAR VALUES INCREASING TO AROUND 40 KT OR SO WHICH
WOULD BE SUFFICIENT FOR AN ORGANIZED SEVERE WEATHER THREAT...THOUGH
THIS THREAT SHOULD DIMINISH WEST TO EAST AS WE GET LATER INTO THE
OVERNIGHT HOURS AND THE BOUNDARY LAYER STABILIZES.
TUESDAY THROUGH THURSDAY...
A SECONDARY SHORTWAVE TROUGH IS PROGGED TO PUSH ACROSS THE REGION ON
TUESDAY BRINGING ADDITIONAL CHANCES FOR SHOWER AND THUNDERSTORMS
MAINLY ACROSS SOUTH/SOUTHEASTERN PORTIONS OF THE CWA WHERE THE
FRONTAL BOUNDARY MAY STILL SLOWLY BE MAKING A PUSH. MODERATE TO
STRONG HEIGHTS RISES QUICKLY BUILD IN BEHIND THIS FEATURE THOUGH AND
SHOULD RESULT IN A DRY WEATHER FOR MOST OF THE FORECAST AREA
TUESDAY. THE GFS IS PARTICULAR IS HOLDING ONTO SOME POPS NORTH OF
THE BOUNDARY WEDNESDAY INTO THURSDAY WHERE PERSISTENT WARM ADVECTION
WILL RESULT IN MID LEVEL ASCENT...THOUGH THE ECMWF REMAINS DRY THIS
PERIOD. WILL MAINTAIN SLIGHT CHANCE POPS IN THE MEANTIME.
FRIDAY THROUGH SATURDAY...
THERMAL RIDGE IS EXPECTED TO MOVE BACK OVERHEAD LATE IN THE WEEK
WITH H85 TEMPS PUSHING INTO THE LOW 20C RANGE WHICH WILL LEAD TO
ANOTHER WARM UP WITH TEMPS INTO THE UPPER 80S. ANOTHER SLOW MOVING
COLD FRONT WILL THEN SAG SOUTH ACROSS THE REGION BRINGING RENEWED
CHANCES FOR SHOWERS AND THUNDERSTORMS.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SLIGHT CHANCE OF FOG/STRATUS EARLY SUNDAY MORNING.
* CHANCE FOR A LAKE BREEZE/WIND SHIFT TO EASTERLY LATE SUNDAY
AFTERNOON.
KREIN
//DISCUSSION...UPDATED 06Z...
SCT TSRA WILL CONTINUE TONIGHT WELL TO THE SOUTHEAST OF THE
TERMINALS OVER EAST CENTRAL IL AND WEST CENTRAL INDIANA. AN OLD
BOUNDARY LIES JUST SOUTH OF THE TERMINALS WITH SLIGHTLY DRIER/LESS
HUMID AIR TO THE NORTH...MOSTLY NOTABLE IN THE DEWPOINT GRADIENT.
GIVEN THE LACK OF RAIN TODAY AND MIXING OUT OF LOW LEVEL
MOISTURE...PLUS THE URBAN HEAT ISLAND EFFECTS...NOT ANTICIPATING
FOG/STRATUS TO BE MUCH OF AN ISSUE FOR THE CHICAGO TERMINALS.
HOWEVER...SHORT RANGE MODEL GUIDANCE IS STILL INDICATING A HIGH
POSSIBILITY OF IFR CIGS/VSBY AWAY FROM THE HIGHLY URBANIZED
AREAS...SO WILL MAINTAIN MVFR/IFR FOG AT THE MORE FOG PRONE
OUTLYING TERMINALS...PARTICULARLY GYY/DPA/RFD. ANY VSBY
RESTRICTIONS THAT DO FORM OVERNIGHT WILL QUICKLY DISSIPATE BY MID
MORNING SUNDAY WITH VFR CONDITIONS EXPECTED THE REMAINDER OF THE
DAY. WINDS SHOULD REMAIN LIGHT ENOUGH TO ALLOW A LAKE BREEZE TO
DEVELOP...BUT THERE APPEARS TO BE LITTLE PUSH BEHIND THE
BOUNDARY...SO AT THIS POINT...FEEL THAT CHANCES ARE LOW THAT THE
LAKE BREEZE WILL PUSH INLAND OF ORD/MDW. HOWEVER...IF THE LAKE
BREEZE DOES MANAGE TO PUSH WEST OF ORD/MDW...IT WOULD NOT BE UNTIL
ARND 22-23Z AND ELY WINDS WOULD BE ARND 5-7KT.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM-HIGH CONFIDENCE IN NO IFR AT ORD/MDW OVERNIGHT.
* MEDIUM TO HIGH CONFIDENCE IN LAKE BREEZE SUNDAY AFTERNOON...AND
MEDIUM CONFIDENCE THAT THE BOUNDARY WILL NOT PUSH THROUGH
ORD/MDW.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...PERIOD OR TWO OF SHRA/TSRA...STRONG TSRA POSSIBLE.
TUESDAY AND WEDNESDAY...PREDOMINANTLY VFR.
THURSDAY...SLIGHT CHANCE TSRA...OTHERWISE VFR.
FRIDAY...CHANCE TSRA.
IZZI
&&
.MARINE...
221 PM CDT
MODERATE SOUTHWEST FLOW IS CURRENTLY IN PLACE ACROSS LAKE MICHIGAN
WHERE SOUTHWEST WINDS ARE GUSTING 20 TO 25 KTS WITH OCCASIONAL 30 KT
WINDS. A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE NEARSHORE
WATERS THROUGH LATE THIS EVENING. THIS IS AHEAD OF LOW PRESSURE
CURRENTLY CENTERED NEAR GREEN BAY. THE LOW WILL DRAG A COLD FRONT
SOUTH ACROSS LAKE MICHIGAN TONIGHT TURNING WINDS TO THE NORTHWEST.
WINDS WILL ABATE BRIEFLY AS TRANSIENT HIGH PRESSURE PUSHES ACROSS
THE NORTHERN LAKES REGION...BUT BY MIDDAY SUNDAY WINDS ARE EXPECTED
TO BEGIN TO TURN SOUTHEAST AND START TO RAMP UP AGAIN AHEAD OF
ANOTHER AREA OF LOW PRESSURE. THIS NEXT WILL LOW LIFT FROM THE
NORTHERN PLAINS...DEEPENING AS IT HEADS TO HUDSON BAY MONDAY NIGHT
INTO TUESDAY. SOUTH WINDS ARE EXPECTED TO PEAK MONDAY OVER THE LAKE
WITH GUSTS SOLIDLY INTO THE 20 KT RANGE...APPROACHING 30 KT OVER THE
NORTH END OF THE LAKE. ANOTHER COLD FRONT WILL SAG SOUTH ACROSS LAKE
MICHIGAN MONDAY NIGHT.
DEUBELBEISS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1251 AM EDT SUN AUG 31 2014
.SYNOPSIS...
ISSUED AT 1250 AM EDT SUN AUG 31 2014
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL REMAIN POSSIBLE
THIS MORNING ALONG A WEAK FRONTAL BOUNDARY. DRIER AIR WILL FILTER
INTO THE AREA LATER TODAY INTO TONIGHT AS HIGH PRESSURE BRIEFLY
BUILDS INTO THE GREAT LAKES REGION. A COLD FRONT WILL PUSH IN FROM
THE WEST MONDAY INTO MONDAY EVENING BRINGING RENEWED CHANCES FOR
SHOWERS AND THUNDERSTORMS. HIGHS WILL REACH INTO THE UPPER 70S TO
LOWS 80 TODAY AND THE LOW TO MID 80S ON MONDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 335 PM EDT SAT AUG 30 2014
CONVECTIVE DEVELOPMENT HAS TRIGGERED WHERE THE CLOUDS CLEARED
EARLIER TODAY...MAINLY OVER CENTRAL ILLINOIS TO LOWER LAKE
MICHIGAN AND INTO NORTHERN MICHIGAN. BEST SYNOPTIC SCALE FORCING
ASSOCIATED WITH THE LOW/TROF IN WISCONSIN. FLOW REGIME IS SUCH
THAT THE CONVECTION HAS DEVELOPED IN A STRETCHING DEFORMATION
AXIS. HRRR AND LOCAL WRF SHOW THE SFC BASED FRONTOGENESIS IN THIS
AXIS...
LAPSE RATES AND WIND PROFILES SUPPORT THE POTENTIAL FOR CONVECTIVE
LINES AND INDIVIDUAL LINE SEGMENTS. ISOLATED THREAT FOR SEVERE WIND
GUSTS. DO NOT EXPECT TO SEE SUSTAINED CONVECTIVE DEVELOPMENT AS THE
BOUNDARY LAYER FORCING DOES NOT PERSIST MUCH PAST 04Z.
LOW LEVEL JET KICKS IN OVERNIGHT AND THIS SHOULD BE ENOUGH TO
SUSTAIN MORE ORGANIZED SHRA/TSRA ACROSS THE SOUTHEASTERN HALF OF THE
FORECAST AREA. WHILE THERE IS DISCREPANCY IN TIMING AND INTENSITY
BETWEEN THE MODELS...THE BOUNDARY LAYER CAPE AND WIND PROFILES ARE
VERY SIMILAR AND DO SUPPORT PERSISTENT/LINGERING SHOWERS THROUGH
SUNDAY MORNING. WITH ABUNDANT MOISTURE TAP AND A LONG FETCH OF
ISENTROPIC ASSENT...SOME OF THE SHOWERS COULD PRODUCE MODERATE TO
LOCALLY HEAVY RAINFALL.
AS THE LOW LEVEL JET DECREASES AND THE TROF/DEFORMATION AXIS SHIFTS
EASTWARD...EXPECT IMPROVING CONDITIONS DURING THE DAY SUNDAY AHEAD
OF ANOTHER MORE ROBUST SYNOPTIC SYSTEM APPROACHING THE AREA FOR
MONDAY.
&&
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 335 PM EDT SAT AUG 30 2014
MAIN FOCUS OF LONG TERM IS ON PRECIP/SEVERE WEATHER CHANCES MONDAY
INTO MONDAY NIGHT. WELL DEFINED MID/UPPER LEVEL TROUGH CURRENTLY
DIGGING INTO THE PACIFIC NORTHWEST WILL SWING THROUGH THE GREAT
LAKES LATE MONDAY. TROUGH WILL BE LIFTING AS IT MOVES THROUGH THE
REGION BUT STRONG PUSH OF HEIGHT FALLS AND CVA WILL SUPPORT A DECENT
SURFACE CYCLONE AND ATTENDANT COLD FRONT. PRECIP CHANCES WILL BE
FURTHER AIDED BY GOOD RIGHT ENTRANCE JET DYNAMICS OVER THE SOUTHERN
GREAT LAKES. DEEP AND STRONG SOUTHWEST FLOW AHEAD OF THE TROUGH WILL
EASILY ADVECT HIGH THETA-E AIRMASS BACK INTO OUR AREA ON MONDAY.
AFTERNOON SBCAPE VALUES EXPECTED TO REACH THE 2-3 KJ/KG RANGE AS
HIGH TEMPS CLIMB INTO THE MID...OR PERHAPS UPPER...80S WITH SURFACE
DEWPOINTS IN THE LOW 70S. VERY DYNAMIC WAVE WILL LIKELY SUPPORT
NUMEROUS SHOWERS AND THUNDERSTORMS BUT TIMING WILL BE CRITICAL TO
SEVERE WEATHER CHANCES. LATEST 12Z NWP SUITE KEEPS SURFACE BOUNDARY
WEST OF OUR CWA UNTIL TUESDAY MORNING. ISO/SCT CONVECTION MAY
DEVELOP IN THE WARM SECTOR MONDAY AFTERNOON ALONG WEAK PREFRONTAL
TROUGH AS SUGGESTED BY THE LATEST NAM12 BUT EXPECT BULK OF THE
ACTIVITY WILL BE TIED TO THE ACTUAL COLD FRONT LATE MONDAY NIGHT.
BETTER WIND PROFILES...WITH 0-6KM SHEAR OF 30+ KNOTS...WILL ALSO BE
TIED CLOSER TO THE FRONT. DESPITE MORE THAN ADEQUATE
SHEAR...MIDLEVEL LAPSE RATES OF 6-7 C/KM ARE ONLY WEAKLY SUPPORTIVE
OF A NOCTURNAL SEVERE WEATHER THREAT. FORECAST SOUNDINGS INDICATE
ONLY AROUND 1000 J/KG OF ELEVATED INSTABILITY MONDAY NIGHT....PLENTY
FOR WIDESPREAD THUNDERSTORMS BUT SEVERE POTENTIAL IS LESS CLEAR.
THERE WILL BE A THREAT FOR SEVERE WINDS...AND POTENTIAL
ROTATION...WITH ANY SUBSTANTIVE UPDRAFTS THAT MANAGE TO DEVELOP BUT
LATE ARRIVAL OF FRONT MAY LIMIT CHANCES FOR A WIDESPREAD SEVERE
WEATHER EVENT. PUSHED BACK TIMING OF POPS BUT ALSO INCREASED THEM A
BIT BASED ON LATEST MODEL SOLUTIONS. COULD ALSO BE A THREAT FOR
STRONGER STORMS IN OUR FAR SOUTHEAST COUNTIES LATE TUESDAY MORNING
IF SURFACE BOUNDARY IS SLOW ENOUGH TO EXIT THE CWA.
QUIET WEATHER EXPECTED MIDWEEK BEFORE ANOTHER TROUGH APPROACHES NEXT
WEEKEND. SCT CONVECTION MAY BE POSSIBLE THURSDAY INTO FRIDAY AS WARM
FRONT LIFTS NORTH ONCE AGAIN BUT BEST CHANCES LOOK TO HOLD OFF UNTIL
THE WEEKEND. AFTER A BRIEF BREAK TUES AND WED...HEAT AND HUMIDITY
WILL RETURN FOR THE END OF THE WEEK AS ACTIVE WEATHER PATTERN
CONTINUES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1250 AM EDT SUN AUG 31 2014
HIGH BOUNDARY LAYER MOISTURE AND WEAK CONVERGENCE INVOF OF A SFC
TROUGH WILL ALLOW CIGS TO LOWER INTO MAINLY IFR-LOW MVFR THIS
MORNING. BROKEN/POORLY ORGANIZED CONVECTIVE LINE ALONG THIS SFC
TROUGH WILL SAG SLOWLY SSE INTO THE KFWA AREA THIS MORNING/EARLY
AFTERNOON. OPTED FOR A VCSH MENTION FOR NOW GIVEN UNCERTAINTY/WEAK
FORCING. PCPN SHOULD REMAIN SOUTH/EAST OF KSBN WITH POTENTIAL FOR
FOG/LIFR CONDITIONS TO FILL IN TOWARD DAYBREAK. CONDITIONS SHOULD
GRADUALLY IMPROVE TO VFR THIS AFTERNOON.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...STEINWEDEL
SHORT TERM...LEWIS
LONG TERM...AGD
AVIATION...STEINWEDEL
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
314 PM CDT SUN AUG 31 2014
.SYNOPSIS...
ISSUED AT 313 PM CDT SUN AUG 31 2014
A WARM...MID SUMMER-LIKE DAY IS FOUND OVER OUR CWA TODAY AS WE
REMAIN WELL EAST OF THE COLD FRONT APPROACHING IOWA THIS AFTERNOON.
THE COLD FRONT IS SLOWLY MOVING EAST...AND HAS ALREADY SPAWNED A FEW
HIGH BASED THUNDERSTORMS FROM SOUTHERN MN TO FAR EASTERN NE.
TEMPERATURES WITH FULL SUN TODAY HAVE REACHED THE MID 80S AS OF 2
PM...AND APPEAR SET FOR HIGHS IN THE MID TO UPPER 80S BEFORE CLOUDS
INTERRUPT THE HEATING LATER THIS AFTERNOON. SURFACE BASED STORMS
REMAIN CAPPED FOR NOW...THOUGH CAPE VALUES ARE SHOWN ON RAP DATA TO BE
2000 TO 4000 J/KG.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 313 PM CDT SUN AUG 31 2014
THERE IS LITTLE DOUBT THERE WILL BE AN IMPRESSIVE CONVECTIVE EVENT
TONIGHT. THERE IS PLENTY OF DOUBT THAT IT WILL STRONGLY AFFECT MORE
THAN JUST THE WESTERN MOST PORTION OF OUR CWA. THE SLOW MOVING
FRONT SHOULD BE ENOUGH TO FOCUS STORMS WITH PLENTY OF CAPE AND
MOISTURE AVAILABLE TO THE WEST...LIKELY NEAR THE MISSOURI RIVER.
THEY SHOULD MOVE EAST...SLOWLY. THIS PLACES THE WEAKENING PHASE OF
THE COMPLEX INTO EASTERN IOWA BETWEEN MIDNIGHT AND 9 AM MONDAY. THIS
POOR DIURNAL TIMING COMBINED WITH LESS THAN IDEAL MOISTURE TRANSPORT
DURING THAT TIME FRAME SUGGESTS BOTH INTENSITY AND COVERAGE OF
STORMS WILL BE ON THE WANE IN THAT PERIOD. I HAVE CONFINED HIGH POPS
TO ONLY THE WESTERN CWA LATE TONIGHT...AND LOWERED TO CHANCE FOR
MONDAY MORNING SINCE MOST MODELS SUGGEST A FRAGMENTED LINE...AND
THAT SEEMS MOST LIKELY TO ME AS WELL. QPF SHOULD BE IMPRESSIVE TO
THE WEST...BUT MAY BE INSIGNIFICANT IN OUR CWA...GENERALLY 0.25 OR
LESS IN ALL BE THE FAR WEST...WHERE 0.5 TO 1.0 IS POSSIBLE.
MONDAY WILL SEE FAR BETTER DYNAMICS...THUS THE SPC OUTLOOK FOR
SEVERE WEATHER. HOWEVER...THE CONVERGENT OUTFLOW BOUNDARY WILL
LIKELY BE WELL IN ADVANCE OF THE COLD FRONT...WHICH SHOULD ALSO
DEFLECT THE STRONGEST HEATING WELL EAST OF THE CWA AS WELL.
THUS...THE WEAKENING CONVECTIVE DEBRIS SHOULD INHIBIT OUR MONDAY
SEVERE POTENTIAL...AS WELL AS WIDESPREAD RAIN POTENTIAL AGAIN. SURE
SEEMS THIS EVENT SHOULD PRODUCE THE MAJORITY OF ITS RAIN WEST AND
SOUTHEAST OF OUR CWA.
ERVIN
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 313 PM CDT SUN AUG 31 2014
THE FRONT WILL CLEAR THE SOUTHEAST HALF OF THE AREA LATE MONDAY
EVENING. THE SOUTHEAST HALF OF THE AREA SHOULD SEE PRECIPITATION
ONGOING AT SUNSET THAT ENDS FROM NORTHWEST TO SOUTHEAST AFTER
MIDNIGHT. DRIER AIR MOVING INTO THE AREA SHOULD RESULT IN LOWS NEAR
OR SLIGHTLY BELOW NORMAL BY SUNRISE TUESDAY.
TUESDAY/TUESDAY NIGHT DRY CONDITIONS ARE EXPECTED AS HIGH PRESSURE
MOVES THROUGH THE MIDWEST. TEMPERATURES SHOULD BE CLOSE TO NORMAL.
WEDNESDAY MORNING LOOKS TO BE DRY ACROSS THE AREA AS THE HIGH MOVES
TOWARD THE EAST COAST. A WEAK DISTURBANCE WILL MOVE THROUGH THE AREA
WEDNESDAY AFTERNOON. THE OVERALL FORCING IS NOT STRONG AND MOISTURE
AVAILABILITY IS IN QUESTION. IF PRECIPITATION DOES OCCUR IT WOULD BE
ISOLATED IN NATURE WITH THE SOUTH HALF BEING FAVORED.
WEDNESDAY NIGHT ON...
THE MODEL CONSENSUS HAS SLIGHT CHANCE TO CHANCE POPS IN EACH 12 HR
PERIOD FROM WEDNESDAY NIGHT THROUGH SATURDAY.
THERE IS A WEAK DISTURBANCE MOVING THROUGH THE AREA WEDNESDAY
NIGHT/THURSDAY. MOISTURE AVAILABILITY WILL BE ON THE INCREASE BUT
THE OVERALL FORCING IS NOT STRONG. THE POSSIBILITY DOES EXIST THERE
WILL BE PERIODS OF DRY WEATHER WEDNESDAY NIGHT/THURSDAY.
THE MODELS DIFFER SOMEWHAT ON THE TIMING BUT AGREE THAT ANOTHER COLD
FRONT WILL MOVE THROUGH THE AREA IN THE THURSDAY NIGHT THROUGH
FRIDAY NIGHT TIME FRAME.
SEVERAL MODELS ARE PUSHING A SIGNIFICANT HIGH INTO THE WESTERN GREAT
LAKES ON SATURDAY. THE CURRENT MODEL CONSENSUS HAS SLIGHT CHANCE
POPS ACROSS THE SOUTH QUARTER OF THE AREA BUT THE OVERALL TREND IS
SUGGESTING DECREASING PRECIPITATION CHANCES.
SATURDAY NIGHT THROUGH SUNDAY THE MODEL CONSENSUS HAS DRY CONDITIONS
WITH HIGH PRESSURE OVER THE GREAT LAKES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1225 PM CDT SUN AUG 31 2014
CLEAR SKIES AND SOUTHERLY WINDS AROUND 12 KTS WILL CONTINUE THIS
AFTERNOON...WITH AN EVENTUAL INCREASE IN MID AND HIGH CLOUDS
TOWARD EVENING AS A COLD FRONT APPROACHES FROM THE WEST. THIS
FRONT WILL BRING WIDESPREAD THUNDERSTORMS TO THE PLAINS...THROUGH
CENTRAL IOWA AND SOUTHERN MINNESOTA THIS AFTERNOON AND EVENING.
HOWEVER...THE LINE OF STORMS SHOULD WEAKEN BELOW SEVERE LEVELS
LATE THIS EVENING AS IT APPROACHES EASTERN IOWA. A PERIOD OF
THUNDERSTORMS AND RAIN IS LIKELY AT DBQ AND CID AS THIS LINE MOVES
EAST. FARTHER SOUTHEAST...THE LINE OF STORMS MAY BREAK UP INTO
SCATTERED SHOWERS...THUS A PROB30 PERIOD OF STORMS IS INCLUDED AT
MLI AND BRL. AFTER STORMS ROLL EAST MONDAY MORNING...A PERIOD OF
MVFR CIGS IS EXPECTED AT ALL SITES.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...08
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS TOPEKA KS
655 PM CDT Mon Sep 1 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Tuesday)
Issued at 319 PM CDT MON SEP 1 2014
Quick cyclonic upper flow remains in place with the core of last
night`s wave already in the Great Lakes and another weaker wave
coming into the High Plains per recent water vapor imagery. The cold
front`s location is hard to nail down behind outflow from the
overnight convection and weak pressure fields, but appears to be
bisecting the local area from southwest to northeast. Lower cloud
under a modest inversion has been rather prevalent today, keeping
temps in the 70s.
Modest convergence persists in east central Kansas this afternoon.
With still some CIN remaining per RAP analysis, confirmed by recent
visible satellite imagery, and the western upper wave staying well
north, storm chances don`t look great, but will maintain some
mention ahead of the front in east central Kansas, diminishing with
time as weak high pressure continues to move across northern sections
of the state. There are some breaks in the clouds to the south, and
some increase in instability is anticipated for the next few hours.
Deep layer is not very high in the weak low level wind fields, but
hard to completely rule out with mixed layer CAPE likely rising to
near 1500 J/kg. As the surface high builds in, winds should be
rather light, and depending on cloud trends particularly with
convection, a fairly good setup for radiational fog will be in place
with cloudy skies and limited mixing today and low cloud scouring
out following the recent heavy rain. Will go ahead with some patchy
fog mention at this point and let later shifts watch trends. Storm
chances continue to look like Tuesday but with the boundary again
possibly not far south, will keep a small chance near it. Better
mixing and insolation should yield highs back into the 80s.
.LONG TERM...(Tuesday Night through Monday)
Issued at 319 PM CDT MON SEP 1 2014
Models continue to show the potential for elevated thunderstorms
and large hail Tuesday night. The one wrinkle is the NAM appears to
be quite a bit stronger in magnitude for both the elevated
instability and effective shear. There is still good theta-e
advection along the nose of the low level jet as well as
isentropic upglide, so I think there should be some storms over
eastern KS. The question is whether they will be strong enough to
produce severe hail. Have continued with a chance POP through the
night and think the potential still exists for some severe storms.
It just may be more marginal than the NAM would suggest.
With the exception of some elevated precip possibly lingering
through the morning Wednesday, the forecast should quiet down as
the models keep the jet stream and synoptic scale energy north of
the forecast through Thursday morning. By Thursday night, a frontal
system is projected to begin moving into the area. There is some
uncertainty in the timing of the frontal system as most solutions
have trended faster with the front, the NAM being the fastest. For
now I`ve not made many changes from the previous forecast thinking
the front would move through mainly Friday and Friday evening with
the higher chances for precip in these periods. However if the
faster trend continues, the POPs may need to be pushed up in the
forecast as well. Have continued to trend POPs down for Saturday
and kept a dry forecast for Sunday with models showing surface
ridging and relatively dryer air over KS. By Monday, there is some
disagreement with the GFS and ECMWF in the amplification of an
upper trough across the west. Because the GFS is the more
amplified solution, it is quick to set up return flow with the
potential for shortwaves within southwesterly flow aloft to pass
near the area. Have taken a conservative approach with the
forecast at this time and have introduced only a slight chance for
precip on Monday until there is a little more agreement in
solutions.
Temps will remain quite warm Wednesday and Thursday as the models
show the thermal ridge over portions of the state. Because of this
have continued with highs in the 90s and lows from around 70 to
the mid 70s. Cold air advection is expected to increase Thursday
night as the front moves through the area. This should bring a
cool down for the weekend with highs in the 70s and lows in the
50s to around 60.
&&
.AVIATION...(For the 00Z TAFs through 00Z Tuesday Evening)
Issued at 634 PM CDT MON SEP 1 2014
Fog at the taf sites later tonight will be the biggest issue with
this forecast period. The low stratus deck which has been around
this afternoon is very slow to progress anywhere. Current
satellite image shows higher cumulus building northward from south
central KS so clearing may be delayed. Also elevated showers are
possible this evening as evident from latest radar although the
models were much further south. These showers could approach MHK
in the next hour. If the clouds are able to clear out later this
evening then the potential for dense fog will be higher.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...65
LONG TERM...Wolters
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1221 PM CDT SUN AUG 31 2014
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT SUN AUG 31 2014
THE HRRR WAS INDICATING A BROKEN LINE OF RELATIVELY LIGHT
REFLECTIVITY MOVING EASTWARD FROM THE AFOREMENTIONED DEVELOPMENT
ZONE INTO CENTRAL KS BY AROUND 10-12 UTC. THIS SOLUTION WAS FOLLOWED
WITH BASICALLY LOW POPS BELOW 20 PERCENT. THE MORE SIGNIFICANT ISSUE
FOR THE DAY WILL BE A LATE DAY OR EVENING SEVERE WEATHER THREAT. THE
NMM AND ARW MODEL RUNS DEVELOPED A QLCS TYPE BOWING SEGMENT ACROSS
NORTHERN KS, ALONG AND AHEAD OF A COLD FRONT/DRYLINE INTERSECTION
OVER NORTHERN KS. FARTHER SOUTH, OVER OUR AREA, ANY CONVECTION IN
THESE SOLUTIONS COULD BE GENERALLY MORE DISCREET AND MORE HIGH BASED
(HAIL AND WIND THREATS POSSIBLE) WITH SUFFICIENT SHEAR FOR
SUPERCELLS. HOWEVER, IT IS POSSIBLE OUTFLOWS/COLD POOLS COULD FORCE
MORE WIDESPREAD DEVELOPMENT FARTHER BRINGING MORE OF OUR AREA
INTO A SEVERE WEATHER THREAT.
SURFACE WINDS WILL BE MORE BREEZY AHEAD OF THE DRYLINE THIS
AFTERNOON. MODELS SUGGEST 15 TO 20 KNOTS SUSTAINED WINDS WILL BE
COMMON WITH GUSTS IN TO JUST UNDER 30 KNOTS. YESTERDAY`S HIGHS OF
LOW 90S TO MID 90S IN THE SOUTHWEST SECTIONS ARE A REASONABLE TELL
FOR HIGHS TODAY. THE LATEST SHORT TERM CONSENSUS SUPPORTS MID 90S
TO NEAR 100 DEGREES IN THE SW GIVEN THE COMBINATION OF SLIGHTLY
DRIER AIR AND BETTER DOWNSLOPE. WITH THE FRONTAL BOUNDARY AND
POTENTIAL MOIST BOUNDARY LAYER OUTFLOW ACROSS THE AREA TONIGHT, A
LARGE GRADIENT OF AROUND 20 DEGREES COULD EXIST FOR OVERNIGHT LOWS
FROM MID 50`S OUT WEST TO MID 70S IN THE PRATT COLDWATER AND
MEDICINE LODGE AREA SETTING AN EARLY MILD LOW JUST AFTER
MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 414 AM CDT SUN AUG 31 2014
THE FRONT FOLLOWING TONIGHTS STORM SYSTEM WILL REACH THE TEXAS
PANHANDLE AND ADJACENT WESTERN OKLAHOMA BY LATE MONDAY/MONDAY NIGHT.
THE DAYTIME HOURS MONDAY WILL BE FAIRLY TRANQUIL AS SUBSIDENCE WILL
PREVAIL IN THE WAKE OF THE DEPARTING SYSTEM. MODEST TEMPERATURES IN
THE 80S ARE EXPECTED. THE FRONT WILL STALL OUT MONDAY NIGHT AND WE
WILL FIND OURSELVES IN THE RIGHT ENTRANCE REGION OF AN UPPER
TROPOSPHERIC JET. THIS WILL ENHANCE FRONTOGENESIS IN THE 900-800MB
LAYER, SUPPORTING NOCTURNAL THUNDERSTORMS ONCE THE LOW LEVEL JET
DEVELOPS. THE MOST FAVORABLE LOCATION FOR MONDAY NIGHT/EARLY TUESDAY
STORMS WILL BE ACROSS SOUTH CENTRAL KANSAS, WHICH IS WHERE WE WILL
HAVE THE HIGHEST CHANCE POPS (AROUND 40 PERCENT). THIS FRONTAL ZONE
WILL NOT MOVE TUESDAY, AND WE WILL NEED TO CARRY SOME CHANCE POPS
THROUGH THE DAY ACROSS SOUTH CENTRAL KANSAS. DAYTIME TEMPERATURES
WILL BE AT OR JUST SLIGHTLY ABOVE AVERAGE FOR THE FIRST PART OF
SEPTEMBER (MID TO UPPER 80S AS A RULE). THE FRONT WILL EVENTUALLY
DISSOLVE BY LATE TUESDAY NIGHT AND ESPECIALLY BY WEDNESDAY, AS THE
LOW LEVEL FLOW FIELD BEGINS TO RESPOND TO LOWER PRESSURE MUCH
FARTHER NORTH WHERE THE POLAR JET WILL BE LOCATED. THE NEXT STORM
SYSTEM MID-WEEK WILL BE MUCH FARTHER NORTH WITH WEAK ZONAL FLOW
ACROSS COLORADO AND KANSAS FOR THE MOST PART. THIS WILL LEAD TO
WARMER TEMPERATURES AND DRIER WEATHER. WEDNESDAY AND THURSDAY
CONTINUE TO LOOK LIKE THE HOTTEST DAYS NEXT WEEK WITH AFTERNOON
HIGHS IN THE 95-100F RANGE FOR MUCH OF WESTERN AND SOUTHERN KANSAS.
THE NORTHERN POLAR JET STORM SYSTEM THAT WAS MENTIONED WILL MOVE
EAST ACROSS THE NORTHERN GREAT PLAINS/ADJACENT CANADIAN PRAIRIES
LATE IN THE WEEK, USHERING IN SOME MUCH COOLER TEMPERATURES ACROSS
THE NORTHERN PLAINS. THIS AIRMASS WILL LIKELY REACH KANSAS BY END OF
WEEK AND INTO THE WEEKEND. THERE APPEARS TO BE A FAIRLY STRONG
SIGNAL OF COOLER/WETTER WEATHER SEPTEMBER 6-8 TIME FRAME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1216 PM CDT SUN AUG 31 2014
A DRYLINE WILL SET UP BETWEEN THE GCK AND DDC TERMINAL THIS
AFTERNOON WITH SOUTH SOUTHWEST WINDS FELT ACROSS THE GCK TERMINAL AND
SOUTH TO SOUTH SOUTHEAST WINDS FELT AT THE HYS AND DDC TERMINALS. BREEZY
CONDITIONS WILL ALSO OCCUR ACROSS THE TAF SITES THIS AFTERNOON WITH
SUSTAINED WINDS ABOVE 20 KNOTS AND GUSTS ABOVE 30 KNOTS. WINDS
THEN DIE DOWN THIS EVENING BEFORE BECOMING LIGHT AND VARIABLE
OVERNIGHT. A FEW THUNDERSTORMS MAY DEVELOP ACROSS THE HYS AND DDC
TERMINALS EARLY THIS EVENING BRIEFLY REDUCING VISIBILITIES AND
CEILINGS. I HAVE PLACED A TEMPO GROUP IN THE TAFS TO REFLECT THIS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 99 65 87 65 / 50 30 10 30
GCK 100 62 87 63 / 20 30 10 20
EHA 100 62 91 63 / 10 10 10 10
LBL 103 65 91 64 / 10 20 10 20
HYS 97 64 84 63 / 50 60 20 20
P28 99 71 90 70 / 10 20 20 50
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUSSELL
LONG TERM...UMSCHEID
AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
715 AM CDT SUN AUG 31 2014
...UPDATED LONG TERM SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT SUN AUG 31 2014
THE HRRR WAS INDICATING A BROKEN LINE OF RELATIVELY LIGHT
REFLECTIVITY MOVING EASTWARD FROM THE AFOREMENTIONED DEVELOPMENT
ZONE INTO CENTRAL KS BY AROUND 10-12 UTC. THIS SOLUTION WAS FOLLOWED
WITH BASICALLY LOW POPS BELOW 20 PERCENT. THE MORE SIGNIFICANT ISSUE
FOR THE DAY WILL BE A LATE DAY OR EVENING SEVERE WEATHER THREAT. THE
NMM AND ARW MODEL RUNS DEVELOPED A QLCS TYPE BOWING SEGMENT ACROSS
NORTHERN KS, ALONG AND AHEAD OF A COLD FRONT/DRYLINE INTERSECTION
OVER NORTHERN KS. FARTHER SOUTH, OVER OUR AREA, ANY CONVECTION IN
THESE SOLUTIONS COULD BE GENERALLY MORE DISCREET AND MORE HIGH BASED
(HAIL AND WIND THREATS POSSIBLE) WITH SUFFICIENT SHEAR FOR
SUPERCELLS. HOWEVER, IT IS POSSIBLE OUTFLOWS/COLD POOLS COULD FORCE
MORE WIDESPREAD DEVELOPMENT FARTHER BRINGING MORE OF OUR AREA
INTO A SEVERE WEATHER THREAT.
SURFACE WINDS WILL BE MORE BREEZY AHEAD OF THE DRYLINE THIS
AFTERNOON. MODELS SUGGEST 15 TO 20 KNOTS SUSTAINED WINDS WILL BE
COMMON WITH GUSTS IN TO JUST UNDER 30 KNOTS. YESTERDAY`S HIGHS OF
LOW 90S TO MID 90S IN THE SOUTHWEST SECTIONS ARE A REASONABLE TELL
FOR HIGHS TODAY. THE LATEST SHORT TERM CONSENSUS SUPPORTS MID 90S
TO NEAR 100 DEGREES IN THE SW GIVEN THE COMBINATION OF SLIGHTLY
DRIER AIR AND BETTER DOWNSLOPE. WITH THE FRONTAL BOUNDARY AND
POTENTIAL MOIST BOUNDARY LAYER OUTFLOW ACROSS THE AREA TONIGHT, A
LARGE GRADIENT OF AROUND 20 DEGREES COULD EXIST FOR OVERNIGHT LOWS
FROM MID 50`S OUT WEST TO MID 70S IN THE PRATT COLDWATER AND
MEDICINE LODGE AREA SETTING AN EARLY MILD LOW JUST AFTER
MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 414 AM CDT SUN AUG 31 2014
THE FRONT FOLLOWING TONIGHTS STORM SYSTEM WILL REACH THE TEXAS
PANHANDLE AND ADJACENT WESTERN OKLAHOMA BY LATE MONDAY/MONDAY NIGHT.
THE DAYTIME HOURS MONDAY WILL BE FAIRLY TRANQUIL AS SUBSIDENCE WILL
PREVAIL IN THE WAKE OF THE DEPARTING SYSTEM. MODEST TEMPERATURES IN
THE 80S ARE EXPECTED. THE FRONT WILL STALL OUT MONDAY NIGHT AND WE
WILL FIND OURSELVES IN THE RIGHT ENTRANCE REGION OF AN UPPER
TROPOSPHERIC JET. THIS WILL ENHANCE FRONTOGENESIS IN THE 900-800MB
LAYER, SUPPORTING NOCTURNAL THUNDERSTORMS ONCE THE LOW LEVEL JET
DEVELOPS. THE MOST FAVORABLE LOCATION FOR MONDAY NIGHT/EARLY TUESDAY
STORMS WILL BE ACROSS SOUTH CENTRAL KANSAS, WHICH IS WHERE WE WILL
HAVE THE HIGHEST CHANCE POPS (AROUND 40 PERCENT). THIS FRONTAL ZONE
WILL NOT MOVE TUESDAY, AND WE WILL NEED TO CARRY SOME CHANCE POPS
THROUGH THE DAY ACROSS SOUTH CENTRAL KANSAS. DAYTIME TEMPERATURES
WILL BE AT OR JUST SLIGHTLY ABOVE AVERAGE FOR THE FIRST PART OF
SEPTEMBER (MID TO UPPER 80S AS A RULE). THE FRONT WILL EVENTUALLY
DISSOLVE BY LATE TUESDAY NIGHT AND ESPECIALLY BY WEDNESDAY, AS THE
LOW LEVEL FLOW FIELD BEGINS TO RESPOND TO LOWER PRESSURE MUCH
FARTHER NORTH WHERE THE POLAR JET WILL BE LOCATED. THE NEXT STORM
SYSTEM MID-WEEK WILL BE MUCH FARTHER NORTH WITH WEAK ZONAL FLOW
ACROSS COLORADO AND KANSAS FOR THE MOST PART. THIS WILL LEAD TO
WARMER TEMPERATURES AND DRIER WEATHER. WEDNESDAY AND THURSDAY
CONTINUE TO LOOK LIKE THE HOTTEST DAYS NEXT WEEK WITH AFTERNOON
HIGHS IN THE 95-100F RANGE FOR MUCH OF WESTERN AND SOUTHERN KANSAS.
THE NORTHERN POLAR JET STORM SYSTEM THAT WAS MENTIONED WILL MOVE
EAST ACROSS THE NORTHERN GREAT PLAINS/ADJACENT CANADIAN PRAIRIES
LATE IN THE WEEK, USHERING IN SOME MUCH COOLER TEMPERATURES ACROSS
THE NORTHERN PLAINS. THIS AIRMASS WILL LIKELY REACH KANSAS BY END OF
WEEK AND INTO THE WEEKEND. THERE APPEARS TO BE A FAIRLY STRONG
SIGNAL OF COOLER/WETTER WEATHER SEPTEMBER 6-8 TIME FRAME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 713 AM CDT SUN AUG 31 2014
STRONG TO SEVERE THUNDERSTORMS WILL DEVELOP ACROSS WESTERN KANSAS
LATE THIS AFTERNOON INTO THIS EVENING. WE WILL GO AHEAD AND
INCLUDE A PROB30 FOR TSRA FOR GCK, DDC, AND HYS FOR A 3 OR 4 HOUR
PERIOD. BY LATE EVENING, THE THUNDERSTORM THREAT WILL MOVE EAST,
LEAVING IN ITS WAKE LIGHTER WINDS FROM THE NORTH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 65 87 65 / 30 50 10 30
GCK 99 62 87 63 / 40 50 10 20
EHA 100 62 91 63 / 10 10 10 10
LBL 102 65 91 64 / 20 20 10 20
HYS 96 64 84 63 / 50 80 20 20
P28 99 71 90 70 / 10 20 20 50
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUSSELL
LONG TERM...UMSCHEID
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
417 AM CDT SUN AUG 31 2014
...UPDATED LONG TERM SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT SUN AUG 31 2014
THE HRRR WAS INDICATING A BROKEN LINE OF RELATIVELY LIGHT
REFLECTIVITY MOVING EASTWARD FROM THE AFOREMENTIONED DEVELOPMENT
ZONE INTO CENTRAL KS BY AROUND 10-12 UTC. THIS SOLUTION WAS FOLLOWED
WITH BASICALLY LOW POPS BELOW 20 PERCENT. THE MORE SIGNIFICANT ISSUE
FOR THE DAY WILL BE A LATE DAY OR EVENING SEVERE WEATHER THREAT. THE
NMM AND ARW MODEL RUNS DEVELOPED A QLCS TYPE BOWING SEGMENT ACROSS
NORTHERN KS, ALONG AND AHEAD OF A COLD FRONT/DRYLINE INTERSECTION
OVER NORTHERN KS. FARTHER SOUTH, OVER OUR AREA, ANY CONVECTION IN
THESE SOLUTIONS COULD BE GENERALLY MORE DISCREET AND MORE HIGH BASED
(HAIL AND WIND THREATS POSSIBLE) WITH SUFFICIENT SHEAR FOR
SUPERCELLS. HOWEVER, IT IS POSSIBLE OUTFLOWS/COLD POOLS COULD FORCE
MORE WIDESPREAD DEVELOPMENT FARTHER BRINGING MORE OF OUR AREA
INTO A SEVERE WEATHER THREAT.
SURFACE WINDS WILL BE MORE BREEZY AHEAD OF THE DRYLINE THIS
AFTERNOON. MODELS SUGGEST 15 TO 20 KNOTS SUSTAINED WINDS WILL BE
COMMON WITH GUSTS IN TO JUST UNDER 30 KNOTS. YESTERDAY`S HIGHS OF
LOW 90S TO MID 90S IN THE SOUTHWEST SECTIONS ARE A REASONABLE TELL
FOR HIGHS TODAY. THE LATEST SHORT TERM CONSENSUS SUPPORTS MID 90S
TO NEAR 100 DEGREES IN THE SW GIVEN THE COMBINATION OF SLIGHTLY
DRIER AIR AND BETTER DOWNSLOPE. WITH THE FRONTAL BOUNDARY AND
POTENTIAL MOIST BOUNDARY LAYER OUTFLOW ACROSS THE AREA TONIGHT, A
LARGE GRADIENT OF AROUND 20 DEGREES COULD EXIST FOR OVERNIGHT LOWS
FROM MID 50`S OUT WEST TO MID 70S IN THE PRATT COLDWATER AND
MEDICINE LODGE AREA SETTING AN EARLY MILD LOW JUST AFTER
MIDNIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 414 AM CDT SUN AUG 31 2014
THE FRONT FOLLOWING TONIGHTS STORM SYSTEM WILL REACH THE TEXAS
PANHANDLE AND ADJACENT WESTERN OKLAHOMA BY LATE MONDAY/MONDAY NIGHT.
THE DAYTIME HOURS MONDAY WILL BE FAIRLY TRANQUIL AS SUBSIDENCE WILL
PREVAIL IN THE WAKE OF THE DEPARTING SYSTEM. MODEST TEMPERATURES IN
THE 80S ARE EXPECTED. THE FRONT WILL STALL OUT MONDAY NIGHT AND WE
WILL FIND OURSELVES IN THE RIGHT ENTRANCE REGION OF AN UPPER
TROPOSPHERIC JET. THIS WILL ENHANCE FRONTOGENESIS IN THE 900-800MB
LAYER, SUPPORTING NOCTURNAL THUNDERSTORMS ONCE THE LOW LEVEL JET
DEVELOPS. THE MOST FAVORABLE LOCATION FOR MONDAY NIGHT/EARLY TUESDAY
STORMS WILL BE ACROSS SOUTH CENTRAL KANSAS, WHICH IS WHERE WE WILL
HAVE THE HIGHEST CHANCE POPS (AROUND 40 PERCENT). THIS FRONTAL ZONE
WILL NOT MOVE TUESDAY, AND WE WILL NEED TO CARRY SOME CHANCE POPS
THROUGH THE DAY ACROSS SOUTH CENTRAL KANSAS. DAYTIME TEMPERATURES
WILL BE AT OR JUST SLIGHTLY ABOVE AVERAGE FOR THE FIRST PART OF
SEPTEMBER (MID TO UPPER 80S AS A RULE). THE FRONT WILL EVENTUALLY
DISSOLVE BY LATE TUESDAY NIGHT AND ESPECIALLY BY WEDNESDAY, AS THE
LOW LEVEL FLOW FIELD BEGINS TO RESPOND TO LOWER PRESSURE MUCH
FARTHER NORTH WHERE THE POLAR JET WILL BE LOCATED. THE NEXT STORM
SYSTEM MID-WEEK WILL BE MUCH FARTHER NORTH WITH WEAK ZONAL FLOW
ACROSS COLORADO AND KANSAS FOR THE MOST PART. THIS WILL LEAD TO
WARMER TEMPERATURES AND DRIER WEATHER. WEDNESDAY AND THURSDAY
CONTINUE TO LOOK LIKE THE HOTTEST DAYS NEXT WEEK WITH AFTERNOON
HIGHS IN THE 95-100F RANGE FOR MUCH OF WESTERN AND SOUTHERN KANSAS.
THE NORTHERN POLAR JET STORM SYSTEM THAT WAS MENTIONED WILL MOVE
EAST ACROSS THE NORTHERN GREAT PLAINS/ADJACENT CANADIAN PRAIRIES
LATE IN THE WEEK, USHERING IN SOME MUCH COOLER TEMPERATURES ACROSS
THE NORTHERN PLAINS. THIS AIRMASS WILL LIKELY REACH KANSAS BY END OF
WEEK AND INTO THE WEEKEND. THERE APPEARS TO BE A FAIRLY STRONG
SIGNAL OF COOLER/WETTER WEATHER SEPTEMBER 6-8 TIME FRAME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1122 PM CDT SAT AUG 30 2014
A VERY SMALL CLUSTER OF GRADUALLY WEAKENING THUNDERSTORMS NEAR
GARDEN CITY EARLIER WERE MOVING TO THE SOUTH OF THE DDC TERMINAL AND
EXPECTED TO NOT HAVE A DIRECT IMPACT. HOWEVER, ELEVATED WARM
ADVECTION SHOWERS AND PROBABLY ISOLATED THUNDERSTORMS MAY MOVE
THROUGH THE AREA BETWEEN 6 AND 10 Z. ANY THUNDERSTORMS SHOULD BE TOO
FEW AND FAR BETWEEN TO CONSIDER FOR EVEN A TEMPO GROUP AT THIS TIME.
SLIGHTLY MORE BREEZY CONDITIONS ARE EXPECTED SUNDAY AFTERNOON AHEAD
OF A SURFACE DRYLINE. THESE MORE BREEZY CONDITIONS ARE EXPECTED FROM
DDC TO HYS. LATE AFTERNOON TO EVENING DEEP MOIST CONVECTION MAY
DEVELOP ANYWHERE ALONG THE DRYLINE OR AND INCOMING COLD FRONT
NORTH OF GARDEN CITY IN THE EVENING, POSSIBLY POSING A LOW
PROBABILITY SEVERE THREAT WITH THE BEST CHANCES NEAR THE HYS
TERMINAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 65 87 65 / 30 50 10 30
GCK 99 62 87 63 / 40 50 10 20
EHA 100 62 91 63 / 10 10 10 10
LBL 102 65 91 64 / 20 20 10 20
HYS 96 64 84 63 / 50 80 20 20
P28 99 71 90 70 / 10 20 20 50
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUSSELL
LONG TERM...UMSCHEID
AVIATION...33
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
337 AM CDT SUN AUG 31 2014
...UPDATED SHORT TERM...
.SYNOPSIS...
ISSUED AT 333 AM CDT SUN AUG 31 2014
WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WERE DEVELOPING
FROM THE NORTHEAST TEXAS PANHANDLE THROUGH LIBERAL AND NORTHWARD TO
NEAR THE I-70 CORRIDOR WEST OF CEDAR BLUFF. THESE WERE ASSOCIATED
WITH A WARM AIR AND MOISTURE ADVECTION PATTERN ACROSS THE WESTERN
1/3 OF KS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT SUN AUG 31 2014
THE HRRR WAS INDICATING A BROKEN LINE OF RELATIVELY LIGHT
REFLECTIVITY MOVING EASTWARD FROM THE AFOREMENTIONED DEVELOPMENT
ZONE INTO CENTRAL KS BY AROUND 10-12 UTC. THIS SOLUTION WAS FOLLOWED
WITH BASICALLY LOW POPS BELOW 20 PERCENT. THE MORE SIGNIFICANT ISSUE
FOR THE DAY WILL BE A LATE DAY OR EVENING SEVERE WEATHER THREAT. THE
NMM AND ARW MODEL RUNS DEVELOPED A QLCS TYPE BOWING SEGMENT ACROSS
NORTHERN KS, ALONG AND AHEAD OF A COLD FRONT/DRYLINE INTERSECTION
OVER NORTHERN KS. FARTHER SOUTH, OVER OUR AREA, ANY CONVECTION IN
THESE SOLUTIONS COULD BE GENERALLY MORE DISCREET AND MORE HIGH BASED
(HAIL AND WIND THREATS POSSIBLE) WITH SUFFICIENT SHEAR FOR
SUPERCELLS. HOWEVER, IT IS POSSIBLE OUTFLOWS/COLD POOLS COULD FORCE
MORE WIDESPREAD DEVELOPMETN FARTHER BRINGING MORE OF OUR AREA INTO A
SEVERE WEATHER THREAT.
SURFACE WINDS WILL BE MORE BREEZY AHEAD OF THE DRYLINE THIS
AFTERNOON. MODELS SUGGEST 15 TO 20 KNOTS SUSTAINED WINDS WILL BE
COMMON WITH GUSTS IN TO JUST UNDER 30 KNOTS. YESTERDAY`S HIGHS OF
LOW 90S TO MID 90S IN THE SOUTHWEST SECTIONS ARE A REASONABLE TELL
FOR HIGHS TODAY. THE LATEST SHORT TERM CONSENSUS SUPPORTS MID 90S
TO NEAR 100 DEGREES IN THE SW GIVEN THE COMBINATION OF SLIGHTLY
DRIER AIR AND BETTER DOWNSLOPE. WITH THE FRONTAL BOUNDARY AND
POTENTIAL MOIST BOUNDARY LAYER OUTFLOW ACROSS THE AREA TONIGHT, A
LARGE GRADIENT OF AROUND 20 DEGREES COULD EXIST FOR OVERNIGHT LOWS
FROM MID 50`S OUT WEST TO MID 70S IN THE PRATT COLDWATER AND
MEDICINE LODGE AREA SETTING AN EARLY MILD LOW JUST AFTER
MIDNIGHT.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 243 PM CDT SAT AUG 30 2014
A SURFACE BOUNDARY WILL EXTEND FROM NORTHEAST COLORADO INTO
NORTH CENTRAL KANSAS AT 00Z SUNDAY AS AN UPPER LEVEL TROUGH
BEGINS TO MOVE OUT INTO THE CENTRAL HIGH PLAINS. GIVEN THE
EXPECTED LOW LEVEL MOISTURE POOLING NORTH OF THIS FRONT ALONG WITH
LOCATION OF THE LEFT EXIT REGION OF AN UPPER LEVEL JET AND LATE
DAY INSTABILITY NEAR THE NORTHERN EDGE OF A +13C TO +16C 700MB
TEMPERATURE GRADIENT WILL CONTINUE TO FAVOR CONVECTION INCREASING
IN AREAL COVERAGE DURING THE EARLY EVENING AS IT SPREADS EAST
ACROSS NORTHWEST AND NORTH CENTRAL KANSAS. SEVERE THUNDERSTORMS
WILL BE POSSIBLE SUNDAY EVENING IN THIS AREA BASED ON THE 0-6KM
SHEAR VALUES RANGING FROM 30 TO 40 KNOTS WITH SURFACE BASED CAPES
GREATER THAN 2000 J/KG. WIDESPREAD HEAVY RAINFALL MAY ALSO BE AN
ISSUE ACROSS NORTH CENTRAL KANSAS OVERNIGHT GIVEN THE PRECIPTABLE
WATER VALUES OF 1.5 TO NEAR 2 INCHES AND A LOW LEVEL JET DEVELOPS
AHEAD OF THE EASTWARD MOVING UPPER LEVEL TROUGH. AT THIS TIME
MODELS DIFFERING SOME ON WHERE THE MID LEVEL BAROCLINIC ZONE WILL
BE SUNDAY NIGHT AND DUE TO LOW CONFIDENCE ON WHERE IT WILL BE
SUNDAY NIGHT HAVE DECIDED TO STAY CLOSE TO THE PREVIOUS FORECAST
ON SOUTHERN EXTENT OF THE OVERNIGHT CONVECTION. THIS WILL KEEP THE
BULK OF PRECIPITATION SUNDAY NIGHT ALONG AND NORTH OF HIGHWAY 96.
FURTHER SOUTH A DRYLINE WILL BE LOCATED ACROSS WESTERN KANSAS,
HOWEVER ABOVE THIS DRYLINE 700MB TEMPERATURES WERE FORECAST TO
WARM TO +14 TO NEAR +16C. THESE WARM MID LEVEL TEMPERATURES WILL
LIMIT HOW WIDESPREAD CONVECTION WILL BE FURTHER SOUTH, HOWEVER AT
THIS TIME AM NOT COMPLETELY ABLE TO RULE ON A FEW SCATTERED/WIDELY
SCATTERED THUNDERSTORMS EARLY SUNDAY NIGHT. WITH SIMILAR
INSTABILITY AND SHEAR VALUES EXPECTED IN THE EVENING ANY STORM
WHICH DOES DEVELOP ALONG THE DRYLINE WILL ALSO HAVE THE POTENTIAL
FOR BECOMING SEVERE.
AS THE UPPER LEVEL TROUGH MOVES INTO CENTRAL NEBRASKA AND NORTH
CENTRAL KANSAS A COLD FRONT WILL MOVE SOUTH ACROSS WESTERN KANSAS
LATE SUNDAY NIGHT. RAIN WILL END FROM WEST TO EAST AND LOWER
DEWPOINTS/COOLER AIR WILL BEGIN TO BRIEFLY SETTLE INTO SOUTHWEST
KANSAS BY EARLY MONDAY. GUSTY NORTH WINDS JUST BEHIND THE FRONT
WILL DECREASE DURING THE DAY AS AN AREA OF HIGH PRESSURE EXITS
MOVES ACROSS NORTHWEST KANSAS. 850MB TEMPERATURES AT 00Z TUESDAY
SUPPORTING HIGHS MAINLY IN THE 80S. HIGHS IN THE LOWER 90S STILL
APPEAR POSSIBLE NEAR THE OKLAHOMA BORDER.
MOISTURE, WARM AIR ADVECTION, AND ISENTROPIC LIFT IMPROVES MONDAY
NIGHT INTO TUESDAY ACROSS SOUTHWEST AND SOUTH CENTRAL KANSAS AS
ANOTHER UPPER LEVEL DISTURBANCE CROSSES THE CENTRAL PLAINS. THIS
WILL RESULT IN INCREASING CLOUDS AND POSSIBLY A FEW
SHOWERS/THUNDERSTORMS NORTH OF OUR SURFACE BOUNDARY. INCREASING
CLOUDS MONDAY NIGHT WILL AID IN KEEPING TEMPERATURES UP WHILE AT
THIS TIME IT APPEARS THE BETTER CHANCES FOR PRECIPITATION WILL BE
ACROSS SOUTH CENTRAL KANSAS.
A WARMING TREND WILL THEN DEVELOP MID WEEK AS A WARM FRONT LIFTS
NORTH ACROSS KANSAS AND A WESTERLY DOWNSLOPE FLOW IMPROVES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1122 PM CDT SAT AUG 30 2014
A VERY SMALL CLUSTER OF GRADUALLY WEAKENING THUNDERSTORMS NEAR
GARDEN CITY EARLIER WERE MOVING TO THE SOUTH OF THE DDC TERMINAL AND
EXPECTED TO NOT HAVE A DIRECT IMPACT. HOWEVER, ELEVATED WARM
ADVECTION SHOWERS AND PROBABLY ISOLATED THUNDERSTORMS MAY MOVE
THROUGH THE AREA BETWEEN 6 AND 10 Z. ANY THUNDERSTORMS SHOULD BE TOO
FEW AND FAR BETWEEN TO CONSIDER FOR EVEN A TEMPO GROUP AT THIS TIME.
SLIGHTLY MORE BREEZY CONDITIONS ARE EXPECTED SUNDAY AFTERNOON AHEAD
OF A SURFACE DRYLINE. THESE MORE BREEZY CONDITIONS ARE EXPECTED FROM
DDC TO HYS. LATE AFTERNOON TO EVENING DEEP MOIST CONVECTION MAY
DEVELOP ANYWHERE ALONG THE DRYLINE OR AND INCOMING COLD FRONT
NORTH OF GARDEN CITY IN THE EVENING, POSSIBLY POSING A LOW
PROBABILITY SEVERE THREAT WITH THE BEST CHANCES NEAR THE HYS
TERMINAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 65 87 65 / 30 50 10 30
GCK 99 62 87 63 / 40 50 10 20
EHA 100 62 91 63 / 10 10 10 10
LBL 102 65 91 64 / 20 20 10 20
HYS 96 64 84 63 / 50 80 20 20
P28 99 71 90 70 / 10 20 20 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RUSSELL
SHORT TERM...RUSSELL
LONG TERM...BURGERT
AVIATION...33
AREA FORECAST DISCUSSION
NWS GOODLAND KS
237 AM MDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 237 AM MDT SUN AUG 31 2014
SHORTWAVE THAT BROUGHT SCATTERED RW/TRW TO PORTIONS OF THE FORECAST
AREA OVERNIGHT WILL CONTINUE TO SHIFT EAST OF THE AREA THIS
MORNING...WITH SOME LINGERING MID CLOUD COVER STILL TO CLR THE
REGION BY MID MORNING. EXPECTING CONDITIONS TO IMPROVE BY MIDDAY
AS WEAK RIDGING PROVIDE SEVERAL HOURS OF DRY CONDITIONS BEFORE
NEXT ROUND OF PRECIPITATION MOVES TO AFFECT THE AREA LATER THIS
AFTERNOON INTO THE EVENING HOURS.
IT IS THIS TIMEFRAME THAT WILL POSE A SEVERE WX THREAT TO MUCH OF
THE TRI STATE REGION. HIGH PRESSURE IS GOING TO GIVE WAY TO A STRONG
SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT LATER THIS AFTERNOON AND
SWING THRU THE AREA THRU 12Z MONDAY. LATEST MODEL TRACK OF THE UPPER
TROUGH THRU THE PERIOD...PUTS BEST DYNAMICS FOR SEVERE CONDITIONS
OVER EASTERN ZONES...ESPECIALLY AREAS NORTH AND EAST OF GOODLAND.
BULK SHEAR 0-6KM WILL RANGING FROM 37 KTS SOUTH TO NEAR 60 KTS
NORTH...COMBINED WITH LL JET 30-40KTS...LI/S -4 TO -8 AND HIGH
DEWPTS WILL ALLOW FOR POTENTIAL SEVERE THUNDER TO DEVELOP...EVEN THE
CHANCE FOR A TORNADO. THIS IS REINFORCED BY SPC PUTTING MUCH OF THE
FORECAST AREA IN SLIGHT RISK IN THE AFOREMENTIONED TIMEFRAME WHERE
DAMAGING WINDS AND LARGE HAIL/TORNADO ARE POSSIBLE. HAVE THUS
CONTINUED ENHANCED WORDING IN FORECAST FOR THESE ELEMENTS. MODELS DO
KEEP SYSTEM FAIRLY PROGRESSIVE THRU THE AREA OVERNIGHT WITH PRECIP
TAPERING FROM WEST TO EAST BY 06Z-12Z.
HIGHS TODAY WILL RANGE FROM THE MID 80S THRU THE MID 90S...WHILE THE
COLD FRONT WILL HELP TO DROP THE AREA INTO THE MID 50S TO LOW 60S
FOR LOWS TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 237 AM MDT SUN AUG 31 2014
GOING INTO MONDAY...FRONTAL BOUNDARY AND ASSOCIATED PRECIPITATION
HAS SHIFTED WELL EAST OF THE FORECAST AREA...ALLOWING FOR HIGH
PRESSURE TO BUILD OVER THE REGION. BY MONDAY EVENING RIGHT INTO
TUESDAY MORNING...MODELS SHOW FRONTAL BOUNDARY STALLING OVER THE
GREAT LKS REGION BACK DOWN ACROSS SOUTHERN PORTIONS OF KANSAS BUT
CLRING OUT BY MIDDAY TUESDAY FOR A QUIET STRETCH OF WEATHER INTO
TUESDAY NIGHT DUE TO SFC HIGH PRESSURE. WITH RIDGE BLOCKING MOST OF
THE CWA FROM THE STALLED FRONT...WILL ONLY PUT IN 15-25 POPS ALONG
EXTREME SOUTHERN ZONES FOR TRW/RW. TEMPERATURES DURING THIS TIME
FRAME WILL RANGE IN THE MID 80S FOR HIGHS...DOWN TO THE MID 50S TO
LOW 60S FOR OVERNGT LOWS.
THE EXTENDED PERIOD WILL START OUT DRY WITH TEMPERATURES WARMER THAN
PREVIOUS DAYS. BROAD UPPER RIDGING WILL CONTINUE ACROSS A LARGE
PORTION OF THE SOUTHERN AND CENTRAL UNITED STATES THROUGH MID WEEK
WITH A PROGRESSIVE ZONAL FLOW PATTERN IN THE HIGHER LATITUDES. LATE
IN THE PERIOD...IN RESPONSE TO A MID/UPPER SHORTWAVE THAT WILL CROSS
THE NORTHERN PLAINS...THE LEE SURFACE TROUGH WILL EVOLVE INTO A
BROAD ELONGATING LOW WITH INCREASING BAROCLINICITY IN THE TRAILING
PORTION THAT MOVES THROUGH OUR AREA. ALONG AND BEHIND THIS
FRONT...SHOWERS AND THUNDERSTORM CHANCES WILL BEGIN THURSDAY NIGHT
AND LAST THROUGH SATURDAY. TEMPERATURES WILL GRADUALLY FALL LATE IN
THE WEEK LIKELY REACHING BELOW NORMAL LEVELS BY THE WEEKEND.
ALTHOUGH SOME DISAGREEMENT EXISTS...CONSENSUS OF DETERMINISTIC
GUIDANCE SEEMS TO FALL IN ABOUT THE MIDDLE OF ENSEMBLE MEMBERS SO
CONFIDENCE IS ABOUT AVERAGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1137 PM MDT SAT AUG 30 2014
PERSISTENT VFR CONDITIONS EXPECTED THROUGH THIS TAF CYCLE.
SHOWERS/ISOLATED STORMS ARE MOVING INTO KGLD SO HAVE PLACED VCTS
BACK INTO TAF. KGLD VAD WIND PROFILE DEPICTS A LOW LEVEL JET OF 45
KTS OVER KGLD AT PRESENT TIME WITH RAP MODEL ANALYSIS INDICATING
STRONG WINDS OVER KMCK. MAINTAINED LLWS IN TAF WITH OUTFLOW
BOUNDARIES AND SOMEWHAT ERRATIC SURFACE WINDS MOVING THROUGH. FOR
THIS AFTERNOON...PLACED VCTS INTO KMCK TAF AS CONVECTION IS
EXPECTED TO DEVELOP AHEAD OF A VIGOROUS UPPER LEVEL DISTURBANCE.
STORMS COULD PRODUCE STRONG WIND GUSTS IN EXCESS OF 50 KTS AND
LARGE HAIL. NOT CONFIDENT ENOUGH TO PLACE TS INTO KGLD TAF AS
MOST MODEL GUIDANCE REMAINS INSISTENT CONVECTION STAYS NORTHEAST.
COLD FRONT SLIDES THROUGH DURING THE EVENING...BRINGING LIGHT
NORTH WINDS AND CALM WEATHER BEHIND THE UPPER LEVEL DISTURBANCE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...JN
LONG TERM...JN/BRB
AVIATION...RRH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
121 AM MDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 119 AM MDT SUN AUG 31 2014
UPDATE ISSUED TO INCREASE POPS FOR TRW/RW THAT HAS DEVELOPED...AND
WILL CARRY THRU UNTIL NEXT ESTF AND/OR 12Z THIS MORNING. BULK OF
ANY REMAINING PRECIP WILL BE FOCUSED OVER AREAS EAST OF GOODLAND.
REST OF FORECAST ON TRACK AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1239 PM MDT SAT AUG 30 2014
18Z WATER VAPOR IMAGERY INDICATED SHORT WAVE RIDGING IN PLACE
ACROSS THE NORTHERN PLAINS WITH NOTICEABLE SHORT WAVE TROUGH
MOVING INTO UTAH. AT THE SURFACE...LEE TROUGH DEVELOPING ACROSS
WESTERN CWA WITH SOUTHWESTERLY WINDS IN THE 10 TO 20 KT RANGE
COMMON.
PRIMARY FORECAST CONCERN WILL CENTER AROUND PRECIP CHANCES THIS
EVENING AND AGAIN ON SUNDAY.
TONIGHT...SHORT WAVE TROUGH CURRENTLY OVER UTAH WILL CONTINUE TO
DRIFT TO THE EAST TONIGHT...WITH LARGE SCALE FORCING INCREASING
BETWEEN 03 AND 09Z IN RESPONSE. INSTABILITY...BOTH SURFACE AND
ELEVATED APPEAR TO BE VERY LIMITED SO DO NOT ANTICIPATE MANY
STRONG/SEVERE STORMS. WHILE A FEW LATE AFTERNOON STORMS ARE
POSSIBLE...DO EXPECT BEST CHANCES TO OCCUR WHEN LARGE SCALE
FORCING/INCREASING LLJ ARE MAXIMIZED.
TOMORROW...POTENTIAL FOR SEVERE THUNDERSTORMS...ESPECIALLY IN THE
EASTERN CWA LOOKS ON TRACK AS FRONTAL BOUNDARY SLOWLY SAGS SOUTH
ACROSS THE AREA. THINK BEST CHANCE FOR CONVECTIVE INITIATION WILL
BE ALONG DEVELOPING DRY LINE TO THE THE SOUTH OF THE FRONTAL ZONE.
WHILE STRONG INSTABILITY AND SHEAR EXIST TO THE NORTH OF
FRONT...STRONG CAP MAKES ANY EARLY INITIATION UNLIKELY. A FEW
STORMS COULD DEVELOP OVER THE HIGHER TERRAIN AND DRIFT INTO THE
CWA...BUT THIS SCENARIO MOST LIKELY AFTER SUNSET.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 230 PM MDT SAT AUG 30 2014
MAIN FOCUS IS STILL ON THE POTENTIAL FOR SEVERE THUNDERSTORMS INTO
SUNDAY EVENING AS SURFACE COLD FRONT MOVES ACROSS THE FORECAST
AREA AND THE AXIS OF THE UPPER TROUGH SWEEPS ACROSS THE CENTRAL
HIGH PLAINS REGION. WITH HIGHS IN THE 90S AND DEWPOINTS IN THE
UPPER 50S TO LOWER 60S...INSTABILITY AND SHEAR SHOULD BE
FAVORABLE FOR SUPERCELLS ACROSS THE EASTERN PORTION OF THE
FORECAST AREA WITH LARGE HAIL AND ISOLATED TORNADOS TRANSITIONING
INTO MAINLY A WIND THREAT BY LATE EVENING.
COOLER...NEAR AVERAGE...TEMPERATURES FOR THIS TIME OF YEAR ARE
EXPECTED ON MONDAY BEHIND THE COLD FRONT AS THE REGION DRIES OUT
WITH HIGH PRESSURE MOVING IN AT THE SURFACE AND THE UPPER FLOW
BECOMING ZONAL THROUGH THE MIDDLE OF THE WEEK. WARMER TEMPERATURES
ARE EXPECTED THROUGH THE LATTER HALF OF THE WEEK AS THE LARGE AREA
OF HIGH PRESSURE ALOFT EXPANDS ACROSS THE SOUTHERN UNITED STATES.
THE UPPER FLOW TURNS MORE SOUTHWESTERLY AND A LEE TROUGH DEEPENS
ALONG THE EASTERN COLORADO BORDER THROUGH THE LATTER HALF OF NEXT
WEEK...BRINGING ANOTHER PERIOD OF ISOLATED TO SCATTERED
THUNDERSTORMS ACROSS THE CENTRAL HIGH PLAINS EACH DAY AS
DISTURBANCES MOVE OUT OF THE SOUTHWEST UNITED STATES...EAST OF THE
ROCKIES...AND ACROSS THE PLAINS STATES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1137 PM MDT SAT AUG 30 2014
PERSISTENT VFR CONDITIONS EXPECTED THROUGH THIS TAF CYCLE.
SHOWERS/ISOLATED STORMS ARE MOVING INTO KGLD SO HAVE PLACED VCTS
BACK INTO TAF. KGLD VAD WIND PROFILE DEPICTS A LOW LEVEL JET OF 45
KTS OVER KGLD AT PRESENT TIME WITH RAP MODEL ANALYSIS INDICATING
STRONG WINDS OVER KMCK. MAINTAINED LLWS IN TAF WITH OUTFLOW
BOUNDARIES AND SOMEWHAT ERRATIC SURFACE WINDS MOVING THROUGH. FOR
THIS AFTERNOON...PLACED VCTS INTO KMCK TAF AS CONVECTION IS
EXPECTED TO DEVELOP AHEAD OF A VIGOROUS UPPER LEVEL DISTURBANCE.
STORMS COULD PRODUCE STRONG WIND GUSTS IN EXCESS OF 50 KTS AND
LARGE HAIL. NOT CONFIDENT ENOUGH TO PLACE TS INTO KGLD TAF AS
MOST MODEL GUIDANCE REMAINS INSISTENT CONVECTION STAYS NORTHEAST.
COLD FRONT SLIDES THROUGH DURING THE EVENING...BRINGING LIGHT
NORTH WINDS AND CALM WEATHER BEHIND THE UPPER LEVEL DISTURBANCE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...JRM
LONG TERM...LOCKHART
AVIATION...RRH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1137 PM MDT SAT AUG 30 2014
.UPDATE...
ISSUED AT 854 PM MDT SAT AUG 30 2014
UPDATED THE FORECAST TO MAKE ADJUSTMENTS FOR THIS EVENING/TONIGHT
AND INCLUDE LATEST GUIDANCE INTO SEVERE WEATHER CHANCES TOMORROW
AFTERNOON/EVENING.
FOR TONIGHT...LOWERED POPS AND MENTIONED ISOLATED THUNDER.
ACTIVITY IS NOT IMPRESSIVE COMING IN FROM COLORADO AND CAP HAS
LIMITED CONVECTION OVER THE TRI-STATE REGION.
FORECAST STILL LOOKS GOOD FOR TOMORROW. BEST CHANCES FOR SEVERE
WEATHER LIES ALONG AND WEST OF HIGHWAY 83. THERE COULD BE A CHANCE
OF A TORNADO OR TWO NORTH AND EAST OF A LINE FROM TRENTON
NEBRASKA TO HOXIE AND HILL CITY KANSAS. LCLS OF 1300-1600
METERS...FAVORABLE SHEAR AND TURNING OF WINDS IN BOUNDARY LAYER
WILL PROVIDE AN ENVIRONMENT CONDUCIVE TO TORNADO DEVELOPMENT. MAIN
THREATS ARE BE LARGE HAIL AND DAMAGING WINDS BUT COULD NOT RULE
OUT A TORNADO OR TWO.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 1239 PM MDT SAT AUG 30 2014
18Z WATER VAPOR IMAGERY INDICATED SHORT WAVE RIDGING IN PLACE
ACROSS THE NORTHERN PLAINS WITH NOTICEABLE SHORT WAVE TROUGH
MOVING INTO UTAH. AT THE SURFACE...LEE TROUGH DEVELOPING ACROSS
WESTERN CWA WITH SOUTHWESTERLY WINDS IN THE 10 TO 20 KT RANGE
COMMON.
PRIMARY FORECAST CONCERN WILL CENTER AROUND PRECIP CHANCES THIS
EVENING AND AGAIN ON SUNDAY.
TONIGHT...SHORT WAVE TROUGH CURRENTLY OVER UTAH WILL CONTINUE TO
DRIFT TO THE EAST TONIGHT...WITH LARGE SCALE FORCING INCREASING
BETWEEN 03 AND 09Z IN RESPONSE. INSTABILITY...BOTH SURFACE AND
ELEVATED APPEAR TO BE VERY LIMITED SO DO NOT ANTICIPATE MANY
STRONG/SEVERE STORMS. WHILE A FEW LATE AFTERNOON STORMS ARE
POSSIBLE...DO EXPECT BEST CHANCES TO OCCUR WHEN LARGE SCALE
FORCING/INCREASING LLJ ARE MAXIMIZED.
TOMORROW...POTENTIAL FOR SEVERE THUNDERSTORMS...ESPECIALLY IN THE
EASTERN CWA LOOKS ON TRACK AS FRONTAL BOUNDARY SLOWLY SAGS SOUTH
ACROSS THE AREA. THINK BEST CHANCE FOR CONVECTIVE INITIATION WILL
BE ALONG DEVELOPING DRY LINE TO THE THE SOUTH OF THE FRONTAL ZONE.
WHILE STRONG INSTABILITY AND SHEAR EXIST TO THE NORTH OF
FRONT...STRONG CAP MAKES ANY EARLY INITIATION UNLIKELY. A FEW
STORMS COULD DEVELOP OVER THE HIGHER TERRAIN AND DRIFT INTO THE
CWA...BUT THIS SCENARIO MOST LIKELY AFTER SUNSET.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 230 PM MDT SAT AUG 30 2014
MAIN FOCUS IS STILL ON THE POTENTIAL FOR SEVERE THUNDERSTORMS INTO
SUNDAY EVENING AS SURFACE COLD FRONT MOVES ACROSS THE FORECAST
AREA AND THE AXIS OF THE UPPER TROUGH SWEEPS ACROSS THE CENTRAL
HIGH PLAINS REGION. WITH HIGHS IN THE 90S AND DEWPOINTS IN THE
UPPER 50S TO LOWER 60S...INSTABILITY AND SHEAR SHOULD BE
FAVORABLE FOR SUPERCELLS ACROSS THE EASTERN PORTION OF THE
FORECAST AREA WITH LARGE HAIL AND ISOLATED TORNADOS TRANSITIONING
INTO MAINLY A WIND THREAT BY LATE EVENING.
COOLER...NEAR AVERAGE...TEMPERATURES FOR THIS TIME OF YEAR ARE
EXPECTED ON MONDAY BEHIND THE COLD FRONT AS THE REGION DRIES OUT
WITH HIGH PRESSURE MOVING IN AT THE SURFACE AND THE UPPER FLOW
BECOMING ZONAL THROUGH THE MIDDLE OF THE WEEK. WARMER TEMPERATURES
ARE EXPECTED THROUGH THE LATTER HALF OF THE WEEK AS THE LARGE AREA
OF HIGH PRESSURE ALOFT EXPANDS ACROSS THE SOUTHERN UNITED STATES.
THE UPPER FLOW TURNS MORE SOUTHWESTERLY AND A LEE TROUGH DEEPENS
ALONG THE EASTERN COLORADO BORDER THROUGH THE LATTER HALF OF NEXT
WEEK...BRINGING ANOTHER PERIOD OF ISOLATED TO SCATTERED
THUNDERSTORMS ACROSS THE CENTRAL HIGH PLAINS EACH DAY AS
DISTURBANCES MOVE OUT OF THE SOUTHWEST UNITED STATES...EAST OF THE
ROCKIES...AND ACROSS THE PLAINS STATES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1137 PM MDT SAT AUG 30 2014
PERSISTENT VFR CONDITIONS EXPECTED THROUGH THIS TAF CYCLE.
SHOWERS/ISOLATED STORMS ARE MOVING INTO KGLD SO HAVE PLACED VCTS
BACK INTO TAF. KGLD VAD WIND PROFILE DEPICTS A LOW LEVEL JET OF 45
KTS OVER KGLD AT PRESENT TIME WITH RAP MODEL ANALYSIS INDICATING
STRONG WINDS OVER KMCK. MAINTAINED LLWS IN TAF WITH OUTFLOW
BOUNDARIES AND SOMEWHAT ERRATIC SURFACE WINDS MOVING THROUGH. FOR
THIS AFTERNOON...PLACED VCTS INTO KMCK TAF AS CONVECTION IS
EXPECTED TO DEVELOP AHEAD OF A VIGOROUS UPPER LEVEL DISTURBANCE.
STORMS COULD PRODUCE STRONG WIND GUSTS IN EXCESS OF 50 KTS AND
LARGE HAIL. NOT CONFIDENT ENOUGH TO PLACE TS INTO KGLD TAF AS
MOST MODEL GUIDANCE REMAINS INSISTENT CONVECTION STAYS NORTHEAST.
COLD FRONT SLIDES THROUGH DURING THE EVENING...BRINGING LIGHT
NORTH WINDS AND CALM WEATHER BEHIND THE UPPER LEVEL DISTURBANCE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...RRH
SHORT TERM...JRM
LONG TERM...LOCKHART
AVIATION...RRH
AREA FORECAST DISCUSSION
NWS JACKSON KY
1045 PM EDT MON SEP 1 2014
.UPDATE...
ISSUED AT 1045 PM EDT MON SEP 1 2014
ISOLATED SHOWERS CONTINUE TO AFFECT NORTHERN KY...INCLUDING THE
NORTHERN PART OF THE JACKSON FORECAST AREA. THE SHOWERS HAVE SHOWN A
DECREASING TREND...AND THE TOTAL LIGHTNING DATA INDICATES THERE IS NO
LONGER ANY LIGHTNING IN KY. CONVECTION CONTINUES TO DEVELOP ACROSS MO
AND CENTRAL IL. BASED ON CURRENT TRENDS AND THE LATEST HRRR DATA THIS
COULD IMPACT OUR AREA BEGINNING SOMETIME NEAR OF AFTER 12Z. HOURLY
NDFD DATA HAS BEEN UPDATED FOR LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 751 PM EDT MON SEP 1 2014
ISOLATED THUNDERSTORMS CONTINUE TO AFFECT THE NORTHERN THIRD OF
KY...INCLUDING THE NORTHERN PART OF THE JACKSON FORECAST AREA. WITH
LOSS OF DAYTIME HEATING EXPECT THE ISOLATED CONVECTION TO CONTINUE TO
WANE. HOWEVER A SHORT WAVE MOVING INTO MO IS RESULTING IN AN
INCREASE IN SHOWERS AND THUNDERSTORMS AHEAD OF THE SURFACE COLD FRONT
THERE...AND THE REMNANTS OF THIS CONVECTION MAY AFFECT THE NORTHERN
PARTS OF THE FORECAST AREA LATE TONIGHT OR EARLY TUESDAY MORNING. THIS
IDEA IS SUPPORTED BY THE LATEST HRRR AND THE 18Z NAM AND GFS. HAVE
UPDATED NDFD FOR LATEST OBSERVATIONAL TRENDS AND WILL BE MAKING
ADDITIONAL ADJUSTMENTS TO HOURLY WEATHER GRIDS SHORTLY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 315 PM EDT MON SEP 1 2014
A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS CONTINUES TO MOVE
ACROSS EASTERN KENTUCKY. THIS LINE IS OUT AHEAD OF THE COLD FRONT IN
THE WARM AIR. THERE IS A BIT OF CURVATURE TO THE LINE OF HEAVIEST
STORMS;...SO WILL BE WATCHING FOR SOME POTENTIALLY STRONG WIND GUSTS
AS THE LINE GOES THROUGH. THE MERCER AND LINCOLN COUNTY MESONET
SITES SAW WIND GUSTS OF 30 MPH AS THE LINE WENT THROUGH AND BATH
COUNTY SAW A GUST TO 41 MPH. CURRENT THINKING IS THE MAX GUSTS STAY
AROUND 40 MPH WITH THE STRONGEST STORMS AND MOST GUSTS WILL BE IN
THE 25 TO 35 MPH RANGE AS THE STORMS CONTINUE TO MOVE ACROSS EASTERN
KENTUCKY. THESE STORMS WILL DROP BETWEEN 0.25 TO 0.75 INCHES OF RAIN
AS IT MOVES ACROSS THE AREA. HAVE A LITTLE CONCERN FOR PARTS OF
EASTERN KENTUCKY THAT GOT HAMMERED LAST NIGHT FROM THE HEAVY
RAIN...HOWEVER THESE STORMS HAVE BEEN QUITE PROGRESSIVE AND HAVE NOT
YET SEEN ANY TRAINING OF THE ECHOES. THIS LINE SHOULD CONTINUE TO
MOVE ACROSS THE AREA AND THEN THE LEADING EDGE OF THE PREFRONTAL
PRECIPITATION WILL BE MOVING INTO THE AREA LATER TONIGHT. THE FRONT
WILL BE MOVING ACROSS THE AREA TOMORROW AND BRING WIDESPREAD SHOWERS
AND THUNDERSTORMS TO THE AREA. THERE WILL BE A SLIGHT RISK OF SEVERE
THUNDERSTORMS TOMORROW. SPC CURRENTLY HAS MOST OF EASTERN KENTUCKY
IN THE SLIGHT RISK AREA. THE MAIN THREAT WILL BE WINDS WITH A VERY
WEAK THREAT FOR MARGINALLY SEVERE HAIL. MOST LIKELY...ANY HAIL WILL
STAY IN THE 0.5 TO 0.75 INCH RANGE. THE PRECIPITATION WILL DROP OFF
FAIRLY QUICKLY BEHIND THE FRONT. THE MODELS ARE IN VERY GOOD
AGREEMENT WITH THE TIMING. WENT WITH THE MODEL BLEND FOR THE
TEMPERATURES WITH JUST SOME ADJUSTMENTS DUE TO ELEVATION.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 315 PM EDT MON SEP 1 2014
THE MODELS BEGIN THE EXTENDED PERIOD IN PRETTY GOOD AGREEMENT ONCE
AGAIN...WITH A RIDGE OF HIGH PRESSURE...BOTH ALOFT AND AT THE
SURFACE...CENTERED OVER THE EASTERN GULF OF MEXICO...ALONG WITH A
WELL DEFINED TROUGH OF LOW PRESSURE ALOFT TAKING SHAPE OVER THE
NORTHERN PLAINS. THE MODELS HAVE THE RIDGE BREAKING DOWN
CONSISTENTLY TO BEGIN THE PERIOD...WITH SHOWERS AND STORMS POPPING
UP BENEATH IT ACROSS THE TENNESSEE VALLEY DOWN TO THE GULF. AS THE
TROUGH EVOLVES AND STRENGTHENS...IT WILL EJECT OUT OF THE PLAINS
WEDNESDAY NIGHT AND THURSDAY...AND PUSH ACROSS THE GREAT LAKES AND
OHIO VALLEY REGIONS. THE COLD FRONT TRAILING FROM THIS UPPER LOW
WILL END BEING OUR WEATHER MAKER FOR THE UPCOMING WEEKEND. THE FRONT
IS EXPECTED TO INTERACT WITH MOISTURE COMING OFF THE GULF OF MEXICO
ON SOUTHWESTERLY WINDS. THE FRONT WILL HAVE A DIFFICULT TIME MOVING
EASTWARD...HOWEVER...AS THE RIDGE DIGS IN A BIT JUST OFF THE
SOUTHEAST COAST AND FLOW ALOFT BECOMES MORE ZONAL. THERE WILL BE A
GOOD CHANCE OF RAIN FRIDAY MORNING THROUGH SUNDAY MORNING...AS LIFT
AND MOISTURE ALONG THE SLUGGISH FRONT SET OFF REPEATED ROUNDS OF
SHOWERS AND STORMS. THE RAIN SHOULD FINALLY MOVE OUT OF THE AREA
SUNDAY EVENING...AS THE FRONT FINALLY MOVES OUT OF THE AREA.
TEMPERATURES TO BEGIN THE PERIOD LOOK TO BE ABOVE NORMAL...WITH
HIGHS TOPPING OUT AROUND IN THE MID TO UPPER 80S WEDNESDAY THROUGH
FRIDAY. ONCE THE FRONT STALLS ACROSS THE AREA AND PRECIPITATION
BECOMES MORE WIDESPREAD...TEMPERATURES WILL LIKELY MAX OUT BELOW
NORMAL VALUES SATURDAY THROUGH MONDAY. HIGHS ON FRIDAY WILL BE
CLOSER TO NORMAL AS THE FRONT WILL STILL BE TO OUR WEST. ON SATURDAY
AND SUNDAY...THE POSITIONING OF THE FRONT WILL ALLOW FOR SOME COOLER
AND DRIER AIR TO FILTER INTO THE AREA. HIGHS ON SATURDAY SHOULD BE
CLOSE TO NORMAL...AS THE BULK OF COOL AIR SHOULD STILL BE TRAPPED
NORTH OF THE OHIO RIVER. ON SUNDAY...HOWEVER...ONCE WINDS HAVE
SHIFTED TO THE NORTH...TEMPERATURES WILL BE QUITE COOL...WITH
READINGS PEAKING IN THE MID TO UPPER 70S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 751 PM EDT MON SEP 1 2014
ISOLATED THUNDERSTORMS OVER NORTHERN KY...NORTH OF THE TAF SITES...
WILL DIMINISH THIS EVENING. VFR CONDITIONS WILL PREVAIL UNTIL AFTER
06Z WHEN AREAS OF FOG WILL BEGIN TO FORM. MVFR CONDITIONS IN FOG ARE
EXPECTED LATE TONIGHT AND EARLY TUESDAY MORNING...BUT ANY FOG WILL
BURN OFF QUICKLY TUESDAY MORNING. VFR CONDITIONS WILL PREVAIL FOR
MOST OF THE DAY ON TUESDAY...BUT AN APPROACHING COLD FRONT WILL BRING
A THREAT OF THUNDERSTORMS DURING THE AFTERNOON AND EVENING. SOUTHWEST
WINDS WILL BECOME GUSTY AHEAD OF THE COLD FRONT TUESDAY
AFTERNOON...WITH SOME GUSTS IN EXCESS OF 15 KNOTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...AR
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
752 PM EDT MON SEP 1 2014
.UPDATE...
ISSUED AT 751 PM EDT MON SEP 1 2014
ISOLATED THUNDERSTORMS CONTINUE TO AFFECT THE NORTHERN THIRD OF
KY...INCLUDING THE NORTHERN PART OF THE JACKSON FORECAST AREA. WITH
LOSS OF DAYTIME HEATING EXPECT THE ISOLATED CONVECTION TO CONTINUE TO
WANE. HOWEVER A SHORT WAVE MOVING INTO MO IS RESULTING IN AN
INCREASE IN SHOWERS AND THUNDERSTORMS AHEAD OF THE SURFACE COLD FRONT
THERE...AND THE REMNANTS OF THIS CONVECTION MAY AFFECT THE NORTHERN
PARTS OF THE FORECAST AREA LATE TONIGHT OR EARLY TUESDAY MORNING. THIS
IDEA IS SUPPORTED BY THE LATEST HRRR AND THE 18Z NAM AND GFS. HAVE
UPDATED NDFD FOR LATEST OBSERVATIONAL TRENDS AND WILL BE MAKING
ADDITIONAL ADJUSTMENTS TO HOURLY WEATHER GRIDS SHORTLY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 315 PM EDT MON SEP 1 2014
A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS CONTINUES TO MOVE
ACROSS EASTERN KENTUCKY. THIS LINE IS OUT AHEAD OF THE COLD FRONT IN
THE WARM AIR. THERE IS A BIT OF CURVATURE TO THE LINE OF HEAVIEST
STORMS;...SO WILL BE WATCHING FOR SOME POTENTIALLY STRONG WIND GUSTS
AS THE LINE GOES THROUGH. THE MERCER AND LINCOLN COUNTY MESONET
SITES SAW WIND GUSTS OF 30 MPH AS THE LINE WENT THROUGH AND BATH
COUNTY SAW A GUST TO 41 MPH. CURRENT THINKING IS THE MAX GUSTS STAY
AROUND 40 MPH WITH THE STRONGEST STORMS AND MOST GUSTS WILL BE IN
THE 25 TO 35 MPH RANGE AS THE STORMS CONTINUE TO MOVE ACROSS EASTERN
KENTUCKY. THESE STORMS WILL DROP BETWEEN 0.25 TO 0.75 INCHES OF RAIN
AS IT MOVES ACROSS THE AREA. HAVE A LITTLE CONCERN FOR PARTS OF
EASTERN KENTUCKY THAT GOT HAMMERED LAST NIGHT FROM THE HEAVY
RAIN...HOWEVER THESE STORMS HAVE BEEN QUITE PROGRESSIVE AND HAVE NOT
YET SEEN ANY TRAINING OF THE ECHOES. THIS LINE SHOULD CONTINUE TO
MOVE ACROSS THE AREA AND THEN THE LEADING EDGE OF THE PREFRONTAL
PRECIPITATION WILL BE MOVING INTO THE AREA LATER TONIGHT. THE FRONT
WILL BE MOVING ACROSS THE AREA TOMORROW AND BRING WIDESPREAD SHOWERS
AND THUNDERSTORMS TO THE AREA. THERE WILL BE A SLIGHT RISK OF SEVERE
THUNDERSTORMS TOMORROW. SPC CURRENTLY HAS MOST OF EASTERN KENTUCKY
IN THE SLIGHT RISK AREA. THE MAIN THREAT WILL BE WINDS WITH A VERY
WEAK THREAT FOR MARGINALLY SEVERE HAIL. MOST LIKELY...ANY HAIL WILL
STAY IN THE 0.5 TO 0.75 INCH RANGE. THE PRECIPITATION WILL DROP OFF
FAIRLY QUICKLY BEHIND THE FRONT. THE MODELS ARE IN VERY GOOD
AGREEMENT WITH THE TIMING. WENT WITH THE MODEL BLEND FOR THE
TEMPERATURES WITH JUST SOME ADJUSTMENTS DUE TO ELEVATION.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 315 PM EDT MON SEP 1 2014
THE MODELS BEGIN THE EXTENDED PERIOD IN PRETTY GOOD AGREEMENT ONCE
AGAIN...WITH A RIDGE OF HIGH PRESSURE...BOTH ALOFT AND AT THE
SURFACE...CENTERED OVER THE EASTERN GULF OF MEXICO...ALONG WITH A
WELL DEFINED TROUGH OF LOW PRESSURE ALOFT TAKING SHAPE OVER THE
NORTHERN PLAINS. THE MODELS HAVE THE RIDGE BREAKING DOWN
CONSISTENTLY TO BEGIN THE PERIOD...WITH SHOWERS AND STORMS POPPING
UP BENEATH IT ACROSS THE TENNESSEE VALLEY DOWN TO THE GULF. AS THE
TROUGH EVOLVES AND STRENGTHENS...IT WILL EJECT OUT OF THE PLAINS
WEDNESDAY NIGHT AND THURSDAY...AND PUSH ACROSS THE GREAT LAKES AND
OHIO VALLEY REGIONS. THE COLD FRONT TRAILING FROM THIS UPPER LOW
WILL END BEING OUR WEATHER MAKER FOR THE UPCOMING WEEKEND. THE FRONT
IS EXPECTED TO INTERACT WITH MOISTURE COMING OFF THE GULF OF MEXICO
ON SOUTHWESTERLY WINDS. THE FRONT WILL HAVE A DIFFICULT TIME MOVING
EASTWARD...HOWEVER...AS THE RIDGE DIGS IN A BIT JUST OFF THE
SOUTHEAST COAST AND FLOW ALOFT BECOMES MORE ZONAL. THERE WILL BE A
GOOD CHANCE OF RAIN FRIDAY MORNING THROUGH SUNDAY MORNING...AS LIFT
AND MOISTURE ALONG THE SLUGGISH FRONT SET OFF REPEATED ROUNDS OF
SHOWERS AND STORMS. THE RAIN SHOULD FINALLY MOVE OUT OF THE AREA
SUNDAY EVENING...AS THE FRONT FINALLY MOVES OUT OF THE AREA.
TEMPERATURES TO BEGIN THE PERIOD LOOK TO BE ABOVE NORMAL...WITH
HIGHS TOPPING OUT AROUND IN THE MID TO UPPER 80S WEDNESDAY THROUGH
FRIDAY. ONCE THE FRONT STALLS ACROSS THE AREA AND PRECIPITATION
BECOMES MORE WIDESPREAD...TEMPERATURES WILL LIKELY MAX OUT BELOW
NORMAL VALUES SATURDAY THROUGH MONDAY. HIGHS ON FRIDAY WILL BE
CLOSER TO NORMAL AS THE FRONT WILL STILL BE TO OUR WEST. ON SATURDAY
AND SUNDAY...THE POSITIONING OF THE FRONT WILL ALLOW FOR SOME COOLER
AND DRIER AIR TO FILTER INTO THE AREA. HIGHS ON SATURDAY SHOULD BE
CLOSE TO NORMAL...AS THE BULK OF COOL AIR SHOULD STILL BE TRAPPED
NORTH OF THE OHIO RIVER. ON SUNDAY...HOWEVER...ONCE WINDS HAVE
SHIFTED TO THE NORTH...TEMPERATURES WILL BE QUITE COOL...WITH
READINGS PEAKING IN THE MID TO UPPER 70S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 751 PM EDT MON SEP 1 2014
ISOLATED THUNDERSTORMS OVER NORTHERN KY...NORTH OF THE TAF SITES...
WILL DIMINISH THIS EVENING. VFR CONDITIONS WILL PREVAIL UNTIL AFTER
06Z WHEN AREAS OF FOG WILL BEGIN TO FORM. MVFR CONDITIONS IN FOG ARE
EXPECTED LATE TONIGHT AND EARLY TUESDAY MORNING...BUT ANY FOG WILL
BURN OFF QUICKLY TUESDAY MORNING. VFR CONDITIONS WILL PREVAIL FOR
MOST OF THE DAY ON TUESDAY...BUT AN APPROACHING COLD FRONT WILL BRING
A THREAT OF THUNDERSTORMS DURING THE AFTERNOON AND EVENING. SOUTHWEST
WINDS WILL BECOME GUSTY AHEAD OF THE COLD FRONT TUESDAY
AFTERNOON...WITH SOME GUSTS IN EXCESS OF 15 KNOTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...JJ
LONG TERM...AR
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS PADUCAH KY
238 PM CDT Sun Aug 31 2014
.SHORT TERM...(Tonight through Tuesday night)
Issued at 238 PM CDT SUN AUG 31 2014
Wvapor and RAP data shows subtle mid level wave moving slowly
east across the area. Convection near SEMO making little eastward
progress. Tiny showers over west KY moving east as well. Will keep
PoPs limited through the early evening before ending them from
west to east overnight. Frontal boundary will approach the area
Monday night. Best chance of activity will be over far north and
west sections of the area. Cannot rule out isolated anywhere, but
chances too low down into west KY to include for now. Moisture is
increasingly limited south of the Ohio. PoPs will rise from NW to
SE Monday night as the front settles south toward the area. Again
best chances north, lowering south. Tuesday the front will stall
somewhere across the area, with upper level support moving across
the region. Thus the chance of convection continues. We could see
some strong storms Tuesday given degree of forecast instability,
and an uptick in the mean flow 850-500mb. Tuesday night we will
drop off PoPs in the wake of the upper system. However more
activity could move into or toward SEMO toward daybreak Wednesday.
Temps will be a blend of existing numbers and the latest blend of
raw model output.
.LONG TERM...(Wednesday through Sunday)
Issued at 238 PM CDT SUN AUG 31 2014
By Wednesday morning, whatever is left of the frontal boundary that
went through the area the night before, will be situated somewhere
over our southern counties. The front will be lifting back north as
a warm front and this is seen most evidently in the theta e fields.
This rebounding front along with minor perturbations in the zonal
flow aloft will likely lead to some convection, especially given the
decent mid level lapse rates, sfc instability parameters and deep
moisture. The upper wave will move off to the east Wednesday night
and things should be fairly quiet except for some possible lingering
afternoon convection.
On Thursday, the upper ridge really begins building over the region
and become centered over us by the end of the day. This should help
boost temperatures up a degree or two into the lower 90s. We should
not see widespread chances for storms though on Thursday, but it
appears as though a small chance will remain, with the best chances
in the east where the better moisture will be confined. Meanwhile, a
frontal boundary will be progressing eastward across the upper
Midwest down into the Central Plains. This front will be slow to
move and models have not been handling its speed very well. Todays
runs of the GFS and ECMWF show a faster progression and have the
front into the area by Friday or Friday night. The best moisture and
QPF is behind the actual front so precipitation chances ramp up by
Friday night into Saturday.
Beyond Saturday, models were having a rough time resolving how
quickly the moisture gets shoved out of the area and this is due to
the differences in the strength and progression of the sfc high
originating from the north central plains states. But the 12Z model
runs of the GFS and ECMWF have finally aligned well and believe that
Sunday (and even Saturday night) should be dry now. In fact, much
drier and cooler air settling in with highs probably in the 70s on
Sunday.
&&
.AVIATION...
Issued at 238 PM CDT SUN AUG 31 2014
Conditions continue to improve given diurnal aspect and with deeper
moisture heading east. Will linger mainly VFR Cu through the end
of the day, with any pockets of MVFR east of a KEVV to KCEY line
giving way to VFR. Chance of convection too low to include at any
of the Terminals. Not too concerned with fog tonight. Cannot rule
out some low cloud development based on moisture transport of
respectable moisture still across the area below 4k/ft. Wind
should stay up enough to preclude a real fog concern. SSW winds
will pick up mid morning Labor day, 10 kts or so, with some CU
expected.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
130 PM EDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 130 PM EDT SUN AUG 31 2014
UPDATED THE FORECAST GRIDS AND FLASH FLOOD WATCH EARLIER THIS
AFTERNOON. SHOWERS AND STORMS ARE ONGOING ACROSS THE AREA...WITH NEW
ACTIVITY BEGINNING TO POP UP IN CENTRAL TENNESSEE AND ALABAMA. AFTER
A LULL IN ACTIVITY...NUMEROUS SHOWERS AND STORMS ARE EXPECTED TO MOVE
BACK INTO THE AREA LATER THIS AFTERNOON INTO THIS EVENING. THE FLASH
FLOOD WATCH IS GOOD UNTIL 6 PM TODAY. WILL CONTINUE TO MONITOR THE
SITUATION TO SEE WHETHER OR NOT WE CAN SHAVE SOME COUNTIES OFF OR
CANCEL IT ALTOGETHER BY THE 4 PM AFTERNOON FORECAST PACKAGE ISSUANCE.
THE FORECAST IS PRETTY MUCH ON TRACK FOR THE DAY SO NO MAJOR CHANGES
HAVE BEEN PLANNED AS OF YET.
UPDATE ISSUED AT 720 AM EDT SUN AUG 31 2014
THE BAND OF RAIN OVER CENTRAL KY IS GRADUALLY WORKING INTO EASTERN
KY. ACTIVITY OVER THE NEXT FEW HOURS SHOULD MAINLY BE ACROSS THE
WESTERN AND NORTHWESTERN LOCATIONS. ACTIVITY SHOULD INCREASE IN
INTENSITY FROM MIDDAY INTO THE AFTERNOON HOURS AND LOCALLY HEAVY RAIN
WILL BE POSSIBLE GIVEN THE VERY MOIST AIR MASS IN PLACE ACROSS THE REGION.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 335 AM EDT SUN AUG 31 2014
EARLY THIS MORNING...THE REGION REMAINED IN A VERY MOIST AIR MASS
WITH PW OF 2 INCHES OR MORE EXTENDING INTO THE OHIO VALLEY REGION
BETWEEN A RIDGE OF HIGH PRESSURE CENTERED OFF THE SOUTHEAST US COAST
AND A SHORTWAVE TROUGH EXTENDING SOUTH FROM THE GREAT LAKES INTO THE
MS VALLEY REGION. A LULL IN THE SHOWER AND THUNDERSTORM ACTIVITY IS
WORKING NORTH AND NORTHEAST ACROSS THE CWA ATTM AS THE FIRST WAVE IS
BEGINNING TO DEPART. HOWEVER...THE NEXT WAVE IS WORKING INTO THE MID
MS AND LOWER OH VALLEY REGION AS THE DEEP MOISTURE PLUME REMAINS.
OVER THE NEXT COUPLE OF DAYS...THE INITIAL WAVE WILL DEPART TO THE
NORTH AND NORTHEAST...BUT THE NEXT MOST EVIDENT AT THE 850 MB AND 700
MB LEVEL IS EXPECTED TO TRACK EAST NORTHEAST ACROSS THE OH VALLEY
REGION TODAY. THIS SYSTEM SHOULD ONCE AGAIN INTERACT WITH THE DEEP
MOISTURE PLUME IN PLACE ACROSS THE REGION AND LEAD TO RENEWED
CONVECTIVE ACTIVITY TO OUR WEST GRADUALLY TRANSITIONING INTO EASTERN KY
LATER TONIGHT AND INTO THE DAY ON SUNDAY. THIS SYSTEM WILL DEPART TO
THE NORTH AND EAST TONIGHT. THE SOUTHEASTERN RIDGE IS EXPECTED TO
FLATTEN BY TONIGHT AND INTO MONDAY. THE NEXT TROUGH WILL HAVE MOVED
INTO THE UPPER MS VALLEY REGION AND PLAINS FROM THE ROCKIES BY LATE
TONIGHT...WITH THIS TROUGH WORKING INTO THE GREAT LAKES AND
APPROACHING THE LOWER OH VALLEY REGION LATE IN THE PERIOD. THE
ASSOCIATED SFC COLD FRONT IS ALSO EXPECTED TO APPROACH THE LOWER OH
VALLEY REGION LATE IN THE PERIOD...BUT WILL HAVE MORE OF AN EFFECT ON
THE LONG TERM PORTION OF THE FORECAST.
RECENT HRRR RUNS BRING THE STRONGEST ACTIVITY ACROSS THE REGION
DURING THE AFTERNOON INTO THE EARLY EVENING ON SUNDAY. THIS ACTIVITY
SHOULD BE EFFICIENT RAIN PRODUCERS AND WHERE ANY TRAINING OCCURS
LOCALLY HEAVY RAIN AND FLASH FLOODING WILL BE POSSIBLE. A FLASH FLOOD
WATCH IS ALREADY IN PLACE ACROSS WESTERN AND NORTHWESTERN PARTS OF
THE CWA ATTM AND WE PLAN TO KEEP IT IN PLACE WITH NO CHANGES. LATER
SHIFTS MAY WANT TO CONSIDER EXTENDING IT FURTHER SOUTH AND EAST...BUT
RAINFALL OVER THE PAST 24 HOURS HAS BEEN GENERALLY LIGHTER THERE
COMPARED TO THE SOUTHWESTERN PART OF THE CWA WHERE RADAR ESTIMATES
AND RAIN GAGES INDICATE THAT UPWARDS OF 2 INCHES OR MORE HAS FALLEN
ACROSS PARTS OF WAYNE COUNTY AND FROM MCCREARY COUNTY NORTHEAST INTO
LAUREL COUNTY. TEMPERATURES TODAY SHOULD BE SUPPRESSED BELOW
SATURDAYS LEVELS BY THE ANTICIPATED CLOUD COVER AND PRECIPITATION.
LOCALLY HEAVY RAIN WILL BE MENTIONED IN THE HWO OUTSIDE OF LOCATIONS
CURRENTLY IN THE FLASH FLOOD WATCH.
WITH THE WAVE DEPARTING TONIGHT...CHANCES FOR CONVECTION WILL ALSO
DIMINISH. MIN TEMPERATURES WILL REMAIN ON THE MILD SIDE. AT LEAST
PATCHY VALLEY FOG SHOULD DEVELOP...WHERE ANY PARTIAL CLEARING
OCCURS. ON MONDAY...THE REGION WILL MORE OR LESS BE IN BETWEEN
SYSTEMS WITH CONTINUED SOUTHERLY FLOW AND NOT MUCH IN THE WAY OF
FORCING. MAX TEMPERATURES WILL AGAIN BE A FEW DEGREES ABOVE NORMAL
AND COULD APPROACH 90 IN SOME LOCATIONS. THE DAYTIME HEATING OF THE
WARM AND RATHER MOIST AIR MASS IN PLACE BY THE AFTERNOON SHOULD LEAD
TO SOME DIURNALLY DRIVEN CONVECTION FOR MONDAY. AT THIS TIME...ONLY
ISOLATED POPS WERE USED.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 252 AM EDT SUN AUG 31 2014
SUMMER-LIKE WEATHER WILL PERSIST THIS WEEK WITH PLENTY OF WARM AND
HUMID CONDITIONS ON TAP. A STRONG RIDGE WILL CONTINUE TO RESIDE OVER
THE SOUTHEAST THROUGH THE WEEK. BEST CHANCE OF RAIN WILL COME ON
TUESDAY AS A SURFACE TROUGH DROPS INTO EASTERN KENTUCKY BEFORE
STALLING. SOME WEAK FORCING WILL YIELD SCATTERED TO NUMEROUS SHOWERS
AND STORMS THROUGH THE AFTERNOON AND EVENING HOURS. DECENT SHEAR
PROFILES...COMBINED WITH MODEST INSTABILITY COULD YIELD THE
POSSIBILITY OF A FEW STRONG TO SEVERE STORMS ON TUESDAY WITH THE
MAIN THREAT BEING DAMAGING WINDS. OTHERWISE...THE FRONT WILL STALL
OVER THE AREA TUESDAY NIGHT...AND VIRTUALLY WASH OUT. THE
THREAT FOR AFTERNOON/EVENING SHOWERS WILL CONTINUE THROUGH WEEKS END
GIVEN THE DAYTIME INSTABILITY EACH AFTERNOON/EVENING. TEMPERATURES
WILL REMAIN NEAR OR SLIGHT ABOVE NORMAL THROUGH THE WEEK WITH ALL
THE COOLER AIR BOTTLED UP WELL TO OUR NORTH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 130 PM EDT SUN AUG 31 2014
MVFR CONDITIONS CAN BE EXPECTED AT THE TAF SITES THROUGH AROUND 13Z
ON MONDAY...AS RAIN AND FOG FROM SHOWER AND STORM ACTIVITY AFFECT THE
TAF AIRPORTS. THE SHOWERS AND STORMS ARE EXPECTED TO TAPER OFF
QUICKLY AFTER 0Z THIS EVENING...WITH ISOLATED ACTIVITY AT BEST ACROSS
THE AREA AFTER 8Z. EASTERN KENTUCKY MIGHT EVEN BE RAIN FREE DURING
THE MORNING HOURS ON MONDAY...BEFORE SHOWERS AND STORMS BEGIN FIRING
UP AGAIN MONDAY AFTERNOON DURING PEAK HEATING AND AS YET ANOTHER
ATMOSPHERIC WAVE MOVES ACROSS THE REGION.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-104-106-108-111-114-116.
&&
$$
UPDATE...AR
SHORT TERM...JP
LONG TERM...KAS
AVIATION...AR
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
730 AM EDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 720 AM EDT SUN AUG 31 2014
THE BAND OF RAIN OVER CENTRAL KY IS GRADUALLY WORKING INTO EASTERN
KY. ACTIVITY OVER THE NEXT FEW HOURS SHOULD MAINLY BE ACROSS THE
WESTERN AND NORTHWESTERN LOCATIONS. ACTIVITY SHOULD INCREASE IN
INTENSITY FROM MIDDAY INTO THE AFTERNOON HOURS AND LOCALLY HEAVY RAIN
WILL BE POSSIBLE GIVEN THE VERY MOIST AIRMASS IN PLACE ACROSS THE REGION.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 335 AM EDT SUN AUG 31 2014
EARLY THIS MORNING...THE REGION REMAINED IN A VERY MOIST AIRMASS
WITH PW OF 2 INCHES OR MORE EXTENDING INTO THE OHIO VALLEY REGION
BETWEEN A RIDGE OF HIGH PRESSURE CENTERED OFF THE SOUTHEAST US COAST
AND A SHORTWAVE TROUGH EXTENDING SOUTH FROM THE GREAT LAKES INTO THE
MS VALLEY REGION. A LULL IN THE SHOWER AND THUNDERSTORM ACTIVITY IS
WORKING NORTH AND NORTHEAST ACROSS THE CWA ATTM AS THE FIRST WAVE IS
BEGINNING TO DEPART. HOWEVER...THE NEXT WAVE IS WORKING INTO THE MID
MS AND LOWER OH VALLEY REGION AS THE DEEP MOISTURE PLUME REMAINS.
OVER THE NEXT COUPLE OF DAYS...THE INITIAL WAVE WILL DEPART TO THE
NORTH AND NORTHEAST...BUT THE NEXT MOST EVIDENT AT THE 850 MB AND 700
MB LEVEL IS EXPECTED TO TRACK EAST NORTHEAST ACROSS THE OH VALLEY
REGION TODAY. THIS SYSTEM SHOULD ONCE AGAIN INTERACT WITH THE DEEP
MOISTURE PLUME IN PLACE ACROSS THE REGION AND LEAD TO RENEWED
CONVECTIVE ACTIVITY TO OUR WEST GRADUALLY TRANSITIONING INTO EASTERN KY
LATER TONIGHT AND INTO THE DAY ON SUNDAY. THIS SYSTEM WILL DEPART TO
THE NORTH AND EAST TONIGHT. THE SOUTHEASTERN RIDGE IS EXPECTED TO
FLATTEN BY TONIGHT AND INTO MONDAY. THE NEXT TROUGH WILL HAVE MOVED
INTO THE UPPER MS VALLEY REGION AND PLAINS FROM THE ROCKIES BY LATE
TONIGHT...WITH THIS TROUGH WORKING INTO THE GREAT LAKES AND
APPROACHING THE LOWER OH VALLEY REGION LATE IN THE PERIOD. THE
ASSOCIATED SFC COLD FRONT IS ALSO EXPECTED TO APPROACH THE LOWER OH
VALLEY REGION LATE IN THE PERIOD...BUT WILL HAVE MORE OF AN EFFECT ON
THE LONG TERM PORTION OF THE FORECAST.
RECENT HRRR RUNS BRING THE STRONGEST ACTIVITY ACROSS THE REGION
DURING THE AFTERNOON INTO THE EARLY EVENING ON SUNDAY. THIS ACTIVITY
SHOULD BE EFFICIENT RAIN PRODUCERS AND WHERE ANY TRAINING OCCURS
LOCALLY HEAVY RAIN AND FLASH FLOODING WILL BE POSSIBLE. A FLASH FLOOD
WATCH IS ALREADY IN PLACE ACROSS WESTERN AND NORTHWESTERN PARTS OF
THE CWA ATTM AND WE PLAN TO KEEP IT IN PLACE WITH NO CHANGES. LATER
SHIFTS MAY WANT TO CONSIDER EXTENDING IT FURTHER SOUTH AND EAST...BUT
RAINFALL OVER THE PAST 24 HOURS HAS BEEN GENERALLY LIGHTER THERE
COMPARED TO THE SOUTHWESTERN PART OF THE CWA WHERE RADAR ESTIMATES
AND RAIN GAGES INDICATE THAT UPWARDS OF 2 INCHES OR MORE HAS FALLEN
ACROSS PARTS OF WAYNE COUNTY AND FROM MCCREARY COUNTY NORTHEAST INTO
LAUREL COUNTY. TEMPERATURES TODAY SHOULD BE SUPPRESSED BELOW
SATURDAYS LEVELS BY THE ANTICIPATED CLOUD COVER AND PRECIPITATION.
LOCALLY HEAVY RAIN WILL BE MENTIONED IN THE HWO OUTSIDE OF LOCATIONS
CURRENTLY IN THE FLASH FLOOD WATCH.
WITH THE WAVE DEPARTING TONIGHT...CHANCES FOR CONVECTION WILL ALSO
DIMINISH. MIN TEMPERATURES WILL REMAIN ON THE MILD SIDE. AT LEAST
PATCHY VALLEY FOG SHOULD DEVELOP...WHERE ANY PARTIAL CLEARING
OCCURS. ON MONDAY...THE REGION WILL MORE OR LESS BE IN BETWEEN
SYSTEMS WITH CONTINUED SOUTHERLY FLOW AND NOT MUCH IN THE WAY OF
FORCING. MAX TEMPERATURES WILL AGAIN BE A FEW DEGREES ABOVE NORMAL
AND COULD APPROACH 90 IN SOME LOCATIONS. THE DAYTIME HEATING OF THE
WARM AND RATHER MOIST AIRMASS IN PLACE BY THE AFTERNOON SHOULD LEAD
TO SOME DIURNALLY DRIVEN CONVECTION FOR MONDAY. AT THIS TIME...ONLY
ISOLATED POPS WERE USED.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 252 AM EDT SUN AUG 31 2014
SUMMER-LIKE WEATHER WILL PERSIST THIS WEEK WITH PLENTY OF WARM AND
HUMID CONDITIONS ON TAP. A STRONG RIDGE WILL CONTINUE TO RESIDE OVER
THE SOUTHEAST THROUGH THE WEEK. BEST CHANCE OF RAIN WILL COME ON
TUESDAY AS A SURFACE TROUGH DROPS INTO EASTERN KENTUCKY BEFORE
STALLING. SOME WEAK FORCING WILL YIELD SCATTERED TO NUMEROUS SHOWERS
AND STORMS THROUGH THE AFTERNOON AND EVENING HOURS. DECENT SHEAR
PROFILES...COMBINED WITH MODEST INSTABILITY COULD YIELD THE
POSSIBILITY OF A FEW STRONG TO SEVERE STORMS ON TUESDAY WITH THE
MAIN THREAT BEING DAMAGING WINDS. OTHERWISE...THE FRONT WILL STALL
OVER THE AREA TUESDAY NIGHT...AND VIRTUALLY WASH OUT. THE
THREAT FOR AFTERNOON/EVENING SHOWERS WILL CONTINUE THROUGH WEEKS END
GIVEN THE DAYTIME INSTABILITY EACH AFTERNOON/EVENING. TEMPERATURES
WILL REMAIN NEAR OR SLIGHT ABOVE NORMAL THROUGH THE WEEK WITH ALL
THE COOLER AIR BOTTLED UP WELL TO OUR NORTH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 725 AM EDT SUN AUG 31 2014
ANOTHER WAVE WILL MOVE NORTHEAST AND INTERACT WITH ABUNDANT MOISTURE
TO BRING A BAND OF RAIN SHOWERS AND SOME EMBEDDED TSRA INTO THE
WESTERN PART OF THE AREA DURING THE FIRST FEW HOURS OF THE PERIOD.
THIS WILL LOWER CIGS GRADUALLY DOWN TOWARD THE MVFR RANGE. AS THE
DISTURBANCE WORKS OVERHEAD THIS AFTERNOON...STRONGER THUNDERSTORMS
MAY DEVELOP WITH LOCALLY HEAVY RAIN. CONFIDENCE IN EXACT TIMING OF
THIS IS LOW AT THIS TIME. CONVECTION SHOULD DIMINISH DURING THE 22Z
TO 4Z PERIOD. PATCHY VALLEY FOG MAY DEVELOP LATE IN THE PERIOD IN THE
DEEPER VALLEYS...BUT MAY NOT AFFECT THE TAF SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-104-106-108-111-114-116.
&&
$$
UPDATE...JP
SHORT TERM...JP
LONG TERM...KAS
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
342 AM EDT SUN AUG 31 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 335 AM EDT SUN AUG 31 2014
EARLY THIS MORNING...THE REGION REMAINED IN A VERY MOIST AIRMASS
WITH PW OF 2 INCHES OR MORE EXTENDING INTO THE OHIO VALLEY REGION
BETWEEN A RIDGE OF HIGH PRESSURE CENTERED OFF THE SOUTHEAST US COAST
AND A SHORTWAVE TROUGH EXTENDING SOUTH FROM THE GREAT LAKES INTO THE
MS VALLEY REGION. A LULL IN THE SHOWER AND THUNDERSTORM ACTIVITY IS
WORKING NORTH AND NORTHEAST ACROSS THE CWA ATTM AS THE FIRST WAVE IS
BEGINNING TO DEPART. HOWEVER...THE NEXT WAVE IS WORKING INTO THE MID
MS AND LOWER OH VALLEY REGION AS THE DEEP MOISTURE PLUME REMAINS.
OVER THE NEXT COUPLE OF DAYS...THE INITIAL WAVE WILL DEPART TO THE
NORTH AND NORTHEAST...BUT THE NEXT MOST EVIDENT AT THE 850 MB AND 700
MB LEVEL IS EXPECTED TO TRACK EAST NORTHEAST ACROSS THE OH VALLEY
REGION TODAY. THIS SYSTEM SHOULD ONCE AGAIN INTERACT WITH THE DEEP
MOISTURE PLUME IN PLACE ACROSS THE REGION AND LEAD TO RENEWED
CONVECTIVE ACTIVITY TO OUR WEST GRADUALLY TRANSITIONING INTO EASTERN KY
LATER TONIGHT AND INTO THE DAY ON SUNDAY. THIS SYSTEM WILL DEPART TO
THE NORTH AND EAST TONIGHT. THE SOUTHEASTERN RIDGE IS EXPECTED TO
FLATTEN BY TONIGHT AND INTO MONDAY. THE NEXT TROUGH WILL HAVE MOVED
INTO THE UPPER MS VALLEY REGION AND PLAINS FROM THE ROCKIES BY LATE
TONIGHT...WITH THIS TROUGH WORKING INTO THE GREAT LAKES AND
APPROACHING THE LOWER OH VALLEY REGION LATE IN THE PERIOD. THE
ASSOCIATED SFC COLD FRONT IS ALSO EXPECTED TO APPROACH THE LOWER OH
VALLEY REGION LATE IN THE PERIOD...BUT WILL HAVE MORE OF AN EFFECT ON
THE LONG TERM PORTION OF THE FORECAST.
RECENT HRRR RUNS BRING THE STRONGEST ACTIVITY ACROSS THE REGION
DURING THE AFTERNOON INTO THE EARLY EVENING ON SUNDAY. THIS ACTIVITY
SHOULD BE EFFICIENT RAIN PRODUCERS AND WHERE ANY TRAINING OCCURS
LOCALLY HEAVY RAIN AND FLASH FLOODING WILL BE POSSIBLE. A FLASH FLOOD
WATCH IS ALREADY IN PLACE ACROSS WESTERN AND NORTHWESTERN PARTS OF
THE CWA ATTM AND WE PLAN TO KEEP IT IN PLACE WITH NO CHANGES. LATER
SHIFTS MAY WANT TO CONSIDER EXTENDING IT FURTHER SOUTH AND EAST...BUT
RAINFALL OVER THE PAST 24 HOURS HAS BEEN GENERALLY LIGHTER THERE
COMPARED TO THE SOUTHWESTERN PART OF THE CWA WHERE RADAR ESTIMATES
AND RAIN GAGES INDICATE THAT UPWARDS OF 2 INCHES OR MORE HAS FALLEN
ACROSS PARTS OF WAYNE COUNTY AND FROM MCCREARY COUNTY NORTHEAST INTO
LAUREL COUNTY. TEMPERATURES TODAY SHOULD BE SUPPRESSED BELOW
SATURDAYS LEVELS BY THE ANTICIPATED CLOUD COVER AND PRECIPITATION.
LOCALLY HEAVY RAIN WILL BE MENTIONED IN THE HWO OUTSIDE OF LOCATIONS
CURRENTLY IN THE FLASH FLOOD WATCH.
WITH THE WAVE DEPARTING TONIGHT...CHANCES FOR CONVECTION WILL ALSO
DIMINISH. MIN TEMPERATURES WILL REMAIN ON THE MILD SIDE. AT LEAST
PATCHY VALLEY FOG SHOULD DEVELOP...WHERE ANY PARTIAL CLEARING
OCCURS. ON MONDAY...THE REGION WILL MORE OR LESS BE IN BETWEEN
SYSTEMS WITH CONTINUED SOUTHERLY FLOW AND NOT MUCH IN THE WAY OF
FORCING. MAX TEMPERATURES WILL AGAIN BE A FEW DEGREES ABOVE NORMAL
AND COULD APPROACH 90 IN SOME LOCATIONS. THE DAYTIME HEATING OF THE
WARM AND RATHER MOIST AIRMASS IN PLACE BY THE AFTERNOON SHOULD LEAD
TO SOME DIURNALLY DRIVEN CONVECTION FOR MONDAY. AT THIS TIME...ONLY
ISOLATED POPS WERE USED.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 252 AM EDT SUN AUG 31 2014
SUMMER-LIKE WEATHER WILL PERSIST THIS WEEK WITH PLENTY OF WARM AND
HUMID CONDITIONS ON TAP. A STRONG RIDGE WILL CONTINUE TO RESIDE OVER
THE SOUTHEAST THROUGH THE WEEK. BEST CHANCE OF RAIN WILL COME ON
TUESDAY AS A SURFACE TROUGH DROPS INTO EASTERN KENTUCKY BEFORE
STALLING. SOME WEAK FORCING WILL YIELD SCATTERED TO NUMEROUS SHOWERS
AND STORMS THROUGH THE AFTERNOON AND EVENING HOURS. DECENT SHEAR
PROFILES...COMBINED WITH MODEST INSTABILITY COULD YIELD THE
POSSIBILITY OF A FEW STRONG TO SEVERE STORMS ON TUESDAY WITH THE
MAIN THREAT BEING DAMAGING WINDS. OTHERWISE...THE FRONT WILL STALL
OVER THE AREA TUESDAY NIGHT...AND VIRTUALLY WASH OUT. THE
THREAT FOR AFTERNOON/EVENING SHOWERS WILL CONTINUE THROUGH WEEKS END
GIVEN THE DAYTIME INSTABILITY EACH AFTERNOON/EVENING. TEMPERATURES
WILL REMAIN NEAR OR SLIGHT ABOVE NORMAL THROUGH THE WEEK WITH ALL
THE COOLER AIR BOTTLED UP WELL TO OUR NORTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 215 AM EDT SUN AUG 31 2014
MVFR OR IFR VIS AND OR CIGS ARE ANTICIPATED AS THE BAND OF CONVECTION
WORKS ACROSS THE EASTERN AND NORTHEASTERN PART OF THE CWA OVER THE
NEXT 2 TO 3 HOURS. VFR HAS DEVELOPED BEHIND THIS BAND OF PRECIPITATION
AND AS THE LULL IN THE ACTIVITY WORKS NORTH ACROSS EAST KY...VFR CIGS
ARE ANTICIPATED UNTIL AT LEAST THE 12Z TO 15Z RANGE. THE PRESS
GRADIENT APPEARS GREAT ENOUGH TO KEEP THE TAF SITES MIXY OVERNIGHT...BUT
SOME MVFR OR LOWER VALLEY FOG MAY STILL DEVELOP BETWEEN 6Z AND 12Z AT
NON TAF SITES. MORE SHOWERS AND SOME THUNDER MAY DEVELOP AGAIN DURING
THE 15Z TO 18Z PERIOD...WITH THIS ACTIVITY DIMINISHING BY THE LAST 6
HOURS OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR KYZ044-050>052-
058>060-068-069-079-080-083>086-104-106-108-111-114-116.
&&
$$
SHORT TERM...JP
LONG TERM...KAS
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
649 PM EDT SUN AUG 31 2014
.SYNOPSIS...
A COLD FRONT WILL DROP SOUTHEAST THROUGH THE REGION O0VERNIGHT
AND WILL STALL OFF THE COAST ON MONDAY. A SECOND COLD FRONT WILL
APPROACH FROM THE WEST ON TUESDAY AND WILL CROSS THE REGION
TUESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE WEST ON
WEDNESDAY AND WILL CREST OVER THE REGION THURSDAY BEFORE SHIFTING
OFFSHORE. HIGH PRESSURE WILL HOLD OFF THE NEW ENGLAND COAST ON
FRIDAY. A COLD FRONT WILL CROSS THE AREA ON SATURDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
UPDATE...LIGHT SHOWERS CONTINUE TO MOVE ACROSS THE BULK OF THE
CWFA ATTM. THIS HAS STABILIZED THE VAST MAJORITY OF THE AREA. THE
LINGERING INSTABILITY AXIS...FROM EARLIER DAYTIME
HEATING...REMAINS ACROSS SERN NH. THIS IS WHERE ANY STRONGER
CONVECTION WILL BE WATCHED TO DEVELOP. CURRENTLY ONE STRONGER
SHOWER IS MOVING TOWARDS THIS AREA...BUT ATTM HEAVY RNFL APPEAR TO
BE THE GREATEST THREAT. HOWEVER...CAPE VALUES REMAIN BETWEEN
500-1000 J/KG PER SPC MESOANALYSIS. WILL MAINTAIN THE GUSTY WIND
AND HEAVY RNFL WORDING IN THE GRIDS...AND JUST ADJUST POP TO
BETTER REFLECT RADAR TRENDS AT THIS HOUR.
WILL ALSO WATCH FOR A SECOND ROUND OF CONVECTION ACROSS THE NRN
ZONES...AS S/WV TROF NEARS LATER THIS EVENING. FORCING JUST
DOWNSTREAM FROM THE S/WV HAS KICKED OFF PLENTY OF TSTMS ACROSS ERN
ONTARIO AND NOW QUEBEC.
PREVIOUS DISCUSSION...A SHORT WAVE TROUGH APPROACHING FROM THE
WEST WILL WEAKEN THIS EVENING AS IT MOVES EASTWARD TOWARD NORTHERN
NEW ENGLAND. THE ATTENDANT SFC COLD FRONT WILL APPROACH AS
WELL...AND ALSO WEAKEN. A SHIELD OF LIGHT RAIN CONTINUES TO
TRAVERSE ACROSS NORTHERN AND CENTRAL ZONES AS OF 19Z THIS SUNDAY
AFTERNOON. THIS WILL STABILIZE THE AIRMASS ACROSS THIS AREA.
HOWEVER...ALONG THE COASTAL PLAIN SWWD OVER TO SOUTHERNMOST NH
SHOULD REMAIN MOSTLY DRY FOR THE NEXT SEVERAL HOURS.
THEREFORE...THESE AREAS SHOULD RETAIN THE INSTABILITY /1000-1500
J/KG SBCAPE/ THROUGH EARLY EVENING. THE QUESTION IS DO
THUNDERSTORMS DEVELOP IN THIS AREA.
SEVERAL OF THE LATEST RUNS OF THE HRRR CONTINUE TO SHOW
THUNDERSTORMS WILL HEAVY RAINFALL MOVING ACROSS SOUTHERNMOST NH
AND SOUTHERNMOST ME BETWEEN 22Z AND 03Z. THIS SEEMS REASONABLE
GIVEN THE CURRENT MESOSCALE SETUP. AS A RESULT WILL CONTINUE WITH
HIGH POPS...ESPECIALLY IN THIS AREA. MODERATE DEEP LAYER SHEAR MAY
AID IN A FEW OF THESE STORMS BECOMING STRONG...WITH GUSTY WINDS
BEING THE MAIN THREAT. WITH PWATS INCREASING TO AROUND 2 INCHES BY
EARLY EVENING...TORRENTIAL DOWNPOURS WILL BE LIKELY IN ANY
THUNDERSTORM. THERE IS A LOW PROB FOR TRAINING STORMS ACROSS
SOUTHERN NH AND SOUTHERNMOST ME...SO LOCALIZED FLASH FLOODING WILL
BE POSSIBLE THIS EVENING. THE BULK OF THE ACTIVITY SHOULD MOVE
OFFSHORE AROUND MIDNIGHT LEADING TO A MAINLY DRY OVERNIGHT.
&&
.SHORT TERM /MONDAY NIGHT/...
ON MONDAY...THE SHORT WAVE TROUGH WILL DEPART IN THE MORNING.
STILL...WITH MODERATE AMOUNTS OF LOW LEVEL THETA-E IN TANDEM WITH
SLIGHTLY COOLER TEMPS ALOFT AND A WEAK SFC FRONT IN THE VCNTY...WE
COULD SEE A FEW SHOWERS DURING THE DAY...PERHAPS A THUNDERSTORM.
HOWEVER...ACTIVITY SHOULD BE FEW AND FAR BETWEEN...WITH HIGHEST
POPS ACROSS CENTRAL AND NORTHERN ZONES. HUMID CONDITIONS WILL
CONTINUE.
MUGGY AND QUIET MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
COLD FRONT APPROACHES FROM THE WEST ON TUESDAY AND WILL
SET THE STAGE FOR POSSIBLE SEVERE WEATHER. PRE-FRONTAL
TROUGH FORECAST TO PUSH IN FROM THE WEST DURING PRIME TIME
HEATING. MODERATE CAPES AND INCREASING SHEAR DURING THE
AFTERNOON AND EVENING HOURS WILL LIKELY RESULT IN MORE
ORGANIZED CONVECTION DURING THE LATE AFTERNOON AND EVENING WITH
DAMAGING WINDS THE MAIN THREAT. STRONGER CELLS MAY ALSO PRODUCE
SOME HAIL BUT FREEZING LEVELS WILL BE QUITE HIGH SO NOT LOOKING
FOR MUCH IN THE WAY OF SEVERE HAIL. WILL SEE A HOT AND MUGGY DAY
WITH HIGHS RANGING THROUGH THE 80S.
COLD FRONT WILL PUSH OFFSHORE TUESDAY NIGHT WITH CONVECTION ENDING
ACROSS THE REGION BY MIDNIGHT. HIGH PRESSURE BUILDING IN FROM THE
WEST WILL BRING CLEARING DOWNWIND OF THE MOUNTAINS. LOW TEMPS
OVERNIGHT WILL RANGE THROUGH THE 60S.
COOLER AND MUCH DRIER AIR PUSHES IN FOR WEDNESDAY AS HIGH PRESSURE
CONTINUES TO BUILD INTO THE NORTHEAST. SHOULD SEE A MOSTLY SUNNY
DAY WITH HIGHS FROM THE MID 70S TO LOWER 80S.
FAIR WEATHER WILL CONTINUE THURSDAY AND FRIDAY AS HIGH PRESSURE
CONTINUES TO BUILD SOUTH OF THE REGION FINALLY PUSHING OFFSHORE
ON FRIDAY. AFTER A STELLAR LATE SUMMER DAY ON THURSDAY...RETURN
FLOW WILL BEGIN TO PUMP WARMER AND MORE HUMID AIR BACK INTO THE
REGION ON FRIDAY. MAY SEE ENOUGH INSTABILITY CREEP INTO THE
CONNECTICUT VALLEY LATE FRIDAY TO KICK OFF AN ISOLATED SHOWER OR
THUNDERSTORM BUT THE MAJORITY OF THE FORECAST AREA WILL SEE A DRY
DAY.
RATHER STRONG LOOKING COLD FRONT FORECAST TO PUSH IN FROM THE WEST
ON SATURDAY WHICH COULD PRODUCE ANOTHER ROUND OF SEVERE
THUNDERSTORMS.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
SHORT TERM...LOCAL IFR IN SHOWERS AND THUNDERSTORMS THIS EVENING.
AFTER MIDNIGHT...FOG AND SOME LOW STRATUS MAY DEVELOP AND RESULT
IN LOW CONDITIONS AS WELL. MAINLY VFR EXPECTED ON MONDAY OUTSIDE
OF WDLY SCT SHOWERS.
LONG TERM...MAINLY VFR EXPECTED OUTSIDE OF ANY SHOWERS AND
THUNDERSTORMS TUE EVE/NIGHT. SOME VALLEY FOG AND COASTAL STRATUS
POSSIBLE DURING THE PERIOD LATE AT NIGHT.
&&
.MARINE...
SHORT TERM...SCA FOR THE OUTER WATERS FOR TONIGHT.
OTHERWISE...SUB-SCA CONDITIONS LIKELY THROUGH MONDAY NIGHT.
LONG TERM...SUB-SCA EXPECTED TUE THROUGH FRI.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ150-152.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS GRAY ME
323 PM EDT SUN AUG 31 2014
.SYNOPSIS...
A COLD FRONT WILL DROP SOUTHEAST THROUGH THE REGION O0VERNIGHT
AND WILL STALL OFF THE COAST ON MONDAY. A SECOND COLD FRONT WILL
APPROACH FROM THE WEST ON TUESDAY AND WILL CROSS THE REGION
TUESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE WEST ON
WEDNESDAY AND WILL CREST OVER THE REGION THURSDAY BEFORE SHIFTING
OFFSHORE. HIGH PRESSURE WILL HOLD OFF THE NEW ENGLAND COAST ON
FRIDAY. A COLD FRONT WILL CROSS THE AREA ON SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A SHORT WAVE TROUGH APPROACHING FROM THE WEST WILL WEAKEN THIS
EVENING AS IT MOVES EASTWARD TOWARD NORTHERN NEW ENGLAND. THE
ATTENDANT SFC COLD FRONT WILL APPROACH AS WELL...AND ALSO WEAKEN.
A SHIELD OF LIGHT RAIN CONTINUES TO TRAVERSE ACROSS NORTHERN AND
CENTRAL ZONES AS OF 19Z THIS SUNDAY AFTERNOON. THIS WILL STABILIZE
THE AIRMASS ACROSS THIS AREA. HOWEVER...ALONG THE COASTAL PLAIN
SWWD OVER TO SOUTHERNMOST NH SHOULD REMAIN MOSTLY DRY FOR THE NEXT
SEVERAL HOURS. THEREFORE...THESE AREAS SHOULD RETAIN THE
INSTABILITY /1000-1500 J/KG SBCAPE/ THROUGH EARLY EVENING. THE
QUESTION IS DO THUNDERSTORMS DEVELOP IN THIS AREA.
SEVERAL OF THE LATEST RUNS OF THE HRRR CONTINUE TO SHOW
THUNDERSTORMS WILL HEAVY RAINFALL MOVING ACROSS SOUTHERNMOST NH
AND SOUTHERNMOST ME BETWEEN 22Z AND 03Z. THIS SEEMS REASONABLE
GIVEN THE CURRENT MESOSCALE SETUP. AS A RESULT WILL CONTINUE WITH
HIGH POPS...ESPECIALLY IN THIS AREA. MODERATE DEEP LAYER SHEAR MAY
AID IN A FEW OF THESE STORMS BECOMING STRONG...WITH GUSTY WINDS
BEING THE MAIN THREAT. WITH PWATS INCREASING TO AROUND 2 INCHES BY
EARLY EVENING...TORRENTIAL DOWNPOURS WILL BE LIKELY IN ANY
THUNDERSTORM. THERE IS A LOW PROB FOR TRAINING STORMS ACROSS
SOUTHERN NH AND SOUTHERNMOST ME...SO LOCALIZED FLASH FLOODING WILL
BE POSSIBLE THIS EVENING. THE BULK OF THE ACTIVITY SHOULD MOVE
OFFSHORE AROUND MIDNIGHT LEADING TO A MAINLY DRY OVERNIGHT.
&&
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
ON MONDAY...THE SHORT WAVE TROUGH WILL DEPART IN THE MORNING.
STILL...WITH MODERATE AMOUNTS OF LOW LEVEL THETA-E IN TANDEM WITH
SLIGHTLY COOLER TEMPS ALOFT AND A WEAK SFC FRONT IN THE VCNTY...WE
COULD SEE A FEW SHOWERS DURING THE DAY...PERHAPS A THUNDERSTORM.
HOWEVER...ACTIVITY SHOULD BE FEW AND FAR BETWEEN...WITH HIGHEST
POPS ACROSS CENTRAL AND NORTHERN ZONES. HUMID CONDITIONS WILL
CONTINUE.
MUGGY AND QUIET MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
COLD FRONT APPROACHES FROM THE WEST ON TUESDAY AND WILL
SET THE STAGE FOR POSSIBLE SEVERE WEATHER. PRE-FRONTAL
TROUGH FORECAST TO PUSH IN FROM THE WEST DURING PRIME TIME
HEATING. MODERATE CAPES AND INCREASING SHEAR DURING THE
AFTERNOON AND EVENING HOURS WILL LIKELY RESULT IN MORE
ORGANIZED CONVECTION DURING THE LATE AFTERNOON AND EVENING WITH
DAMAGING WINDS THE MAIN THREAT. STRONGER CELLS MAY ALSO PRODUCE
SOME HAIL BUT FREEZING LEVELS WILL BE QUITE HIGH SO NOT LOOKING
FOR MUCH IN THE WAY OF SEVERE HAIL. WILL SEE A HOT AND MUGGY DAY
WITH HIGHS RANGING THROUGH THE 80S.
COLD FRONT WILL PUSH OFFSHORE TUESDAY NIGHT WITH CONVECTION ENDING
ACROSS THE REGION BY MIDNIGHT. HIGH PRESSURE BUILDING IN FROM THE
WEST WILL BRING CLEARING DOWNWIND OF THE MOUNTAINS. LOW TEMPS
OVERNIGHT WILL RANGE THROUGH THE 60S.
COOLER AND MUCH DRIER AIR PUSHES IN FOR WEDNESDAY AS HIGH PRESSURE
CONTINUES TO BUILD INTO THE NORTHEAST. SHOULD SEE A MOSTLY SUNNY
DAY WITH HIGHS FROM THE MID 70S TO LOWER 80S.
FAIR WEATHER WILL CONTINUE THURSDAY AND FRIDAY AS HIGH PRESSURE
CONTINUES TO BUILD SOUTH OF THE REGION FINALLY PUSHING OFFSHORE
ON FRIDAY. AFTER A STELLAR LATE SUMMER DAY ON THURSDAY...RETURN
FLOW WILL BEGIN TO PUMP WARMER AND MORE HUMID AIR BACK INTO THE
REGION ON FRIDAY. MAY SEE ENOUGH INSTABILITY CREEP INTO THE
CONNECTICUT VALLEY LATE FRIDAY TO KICK OFF AN ISOLATED SHOWER OR
THUNDERSTORM BUT THE MAJORITY OF THE FORECAST AREA WILL SEE A DRY
DAY.
RATHER STRONG LOOKING COLD FRONT FORECAST TO PUSH IN FROM THE WEST
ON SATURDAY WHICH COULD PRODUCE ANOTHER ROUND OF SEVERE
THUNDERSTORMS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...LOCAL IFR IN SHOWERS AND THUNDERSTORMS THIS EVENING.
AFTER MIDNIGHT...FOG AND SOME LOW STRATUS MAY DEVELOP AND RESULT
IN LOW CONDITIONS AS WELL. MAINLY VFR EXPECTED ON MONDAY OUTSIDE
OF WDLY SCT SHOWERS.
LONG TERM...MAINLY VFR EXPECTED OUTSIDE OF ANY SHOWERS AND
THUNDERSTORMS TUE EVE/NIGHT. SOME VALLEY FOG AND COASTAL STRATUS
POSSIBLE DURING THE PERIOD LATE AT NIGHT.
&&
.MARINE...
SHORT TERM...SCA FOR THE OUTER WATERS FOR TONIGHT.
OTHERWISE...SUB-SCA CONDITIONS LIKELY THROUGH MONDAY NIGHT.
LONG TERM...SUB-SCA EXPECTED TUE THROUGH FRI.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ150-152.
&&
$$
NEAR TERM...MLE
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1028 PM EDT MON SEP 1 2014
.SYNOPSIS...
A BERMUDA HIGH WILL PERSIST THROUGH TUESDAY. A COLD FRONT WILL
CROSS THE AREA TUESDAY NIGHT...FOLLOWED BY HIGH PRESSURE THROUGH
THE REST OF THE WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
SURFACE HIGH PRESSURE PERSISTS OFFSHORE. WATER VAPOR IMAGERY
INDICATES AN UPPER DISTURBANCE MOVING ACROSS WV. SHOWER ACTIVITY HAS
BECOME VERY ISOLATED. ONE SHOWER NEAR WARM SPRINGS VA MAY BRUSH
THE SOUTHERN TIER OF THE FORECAST AREA IN THE NEXT COUPLE OF
HOURS...AND OTHER SPOTTY AREAS OF LIGHT RAIN ARE APPROACHING THE
SHENANDOAH VALLEY. HRRR HAS DEPICTED THIS PRETTY WELL...AND
INDICATES SOME ADDITIONAL SHOWER ACTIVITY WILL BE POSSIBLE AS THE
DISTURBANCE MOVES ACROSS THE CWA OVER THE NEXT SEVERAL HOURS. KEPT
MENTION OF THUNDER ACROSS THE POTOMAC HIGHLANDS. ALTHOUGH IT
SHOULD BE ISOLATED...CLOUD TOPS ON THE SHOWER NEAR WARM SPRINGS
ARE AT -36C...INDICATING ENOUGH INSTABILITY FOR A FEW LIGHTNING
STRIKES.
WILL HAVE POTENTIAL FOR FOG TONIGHT WITH MOIST AIRMASS IN
PLACE...BUT IT MAY BE INHIBITED IN SOME SPOTS WITH APPROACHING
CLOUDS FROM THE DISTURBANCE TO OUR WEST.
LOWS GENERALLY IN THE UPPER 60S TO LOW 70S TONIGHT...AND SLIGHTLY
COOLER IN ELEVATED AREAS.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
COLD FRONT WILL STILL BE LOCATED ACROSS THE OHIO VALLEY AT 12Z TUE.
BUT FRONT WILL MARCH EASTWARD THROUGH THE DAY...MAKING IT TO THE
POTOMAC HIGHLANDS BY LATE AFTERNOON. PRE-FRONTAL ENVIRONMENT WILL BE
WARM AND MOIST...BUT CONVECTION LIKELY WAITS UNTIL THE FRONT GETS
CLOSER TO THE CWA AND HAVE POPS EXPANDING EASTWARD WITH TIME HIGHEST
IN THE EVENING ACROSS THE INTERSTATE 95 CORRIDOR.
THERE IS THE RISK FOR A FEW STORMS TO BECOME SEVERE /DAMAGING WIND
GUSTS/ TUESDAY...ESPECIALLY BEFORE DARK DUE TO THE COMBINATION OF
INSTABILITY AND INCREASED SHEAR. CONFIDENCE IS LOWER FURTHER
DOWNSTREAM ONCE THE SUN SETS. FRONT MOVES THROUGH AT NIGHT. POPS
LOWER FROM WEST TO EAST.
DRIER AIR MOVES IN FOR WEDNESDAY WITH THE RETURN OF SUNSHINE. WHILE
DEWPOINTS ARE LOWER...DOWNSLOPING WILL SUPPORT ABOVE NORMAL
TEMPERATURES WHICH STILL MAY BE NEAR 90. SAME TYPE OF SCENARIO ON
THURSDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
WEAK SURFACE TROUGH...MOISTURE AND WEAK PVA MAY BE ENOUGH TO SUPPLY
A SLIGHT CHANCE OF SHOWERS/THUNDERSTORMS FRIDAY. INCREASED MOISTURE
AND THE PASSAGE OF COLD FRONT WILL SUPPORT DEVELOPMENT OF STRONGER
ACTIVITY OVER THE WEEKEND AND INTO MONDAY.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
PRIMARILY VFR CONDITIONS EXPECTED THIS EVENING INTO THE OVERNIGHT
HOURS...ALTHOUGH A BRIEF SHOWER IS POSSIBLE AT ALL TERMINALS
OUTSIDE OF BWI/MTN. FOG MAY DEVELOP LATE TONIGHT WITH A MOIST AIRMASS
IN PLACE.
TSRA POSSIBLE AGAIN TUESDAY AFTERNOON/EVENING AHEAD OF A COLD
FRONT.
NO SIGNIFICANT WEATHER EXPECTED MID TO LATE WEEK.
&&
.MARINE...
EARLIER GUSTS ON THE WATERS NEAR TANGIER SOUND HAVE DIMINISHED.
WINDS GENERALLY FROM THE SOUTH 10KT OR LESS TONIGHT.
APPROACHING COLD FRONT WILL LIKELY PRODUCE SCATTERED THUNDERSTORMS
LATE TUESDAY AFTERNOON AND EVENING...WITH GUSTY WINDS POSSIBLE.
FRONT MOVES THROUGH TUESDAY NIGHT WITH HIGH PRESSURE BUILDING IN
FOR WEDNESDAY.
SOUTHERLY CHANNELLING/SCA CONDITIONS COULD BE POSSIBLE LATE
FRIDAY. COLD FRONT EXPECTED TO MOVE THROUGH OVER THE WEEKEND.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CEM/BPP
NEAR TERM...BPP/KCS
SHORT TERM...BPP
LONG TERM...CEM
AVIATION...CEM/BPP/KCS
MARINE...CEM/BPP/KCS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
329 PM EDT SUN AUG 31 2014
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL PERSIST THROUGH TUESDAY WITH AN ACTIVE
PATTERN FOR THE EASTERN SEABOARD. A WEAK COLD FRONT WILL CROSS THE
AREA TUESDAY NIGHT...FOLLOWED BY HIGH PRESSURE.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AREA BETWEEN I-81 AND THE BAY HAS RECEIVED PLENTY OF INSOLATION
TODAY...WHICH SUPPORTS THE DVLPMNT OF LEE TROFFING EVIDENT IN LTST
SFC ANALY. OTRW...THE NEAREST SYNOP FEATURE IS A WK CDFNT IN THE
ST LAWR VLY SWWD TO DTW. A BKN LINE OF SHRA/TSRA HAS DVLPD ALONG
THE DIFFERENTIAL HEATING BNDRY...FM FDK-OKV-HIGHLAND CO VA. ADDTL
TSRA CAN BE FOUND JUST OVER THE SUSQ RIVER IN CECIL CO.
MESO ANALY SUGGESTS A RIBBON OF MUCAPE AOA 2000 J/KG AND EFFECTIVE
BULK SHEAR ALONG AND JUST E OF THE AREA WHERE STORMS FORMING.
THEREFORE...SEE NO REASON WHY DVLPMNT WONT CONTINUE. HRRR HAS BEEN
PERFORMING RATHER WELL THUS FAR TDA. IT SUGGESTS THAT PCPN WL CONT
TO FILL IN AS AREA HEADS TWD I-95 BY 20-22Z. FCST IS BASED ON THIS
SCENARIO.
THERES ENUF CAPE AND SHEAR FOR ORGANIZATION TO OCCUR. THUS FAR
THATS FAILED TO HPPN...LKLY DUE TO WK MID LVL LAPSE RATES. IF WE
CAN OVERCOME THE ISSUES IN THE MID LVLS...THEN THE MOST LKLY
THREAT WUD COME FROM WET MICROBURSTS. IN ADDITION...PWAT NEAR 2
INCHES WUD SUPPORT HVY RAINERS.
THE TAIL OF A PVA LOBE WL CROSS THE AREA BTWN 00-06Z. HV HELD ONTO
LKLY OR HIER POPS ALL AREAS XCPT FOR CHO-EZF-NHK DUE TO THIS ADDED
SUPPORT. ONCE WE GET TOO MUCH LATER THAN THAT...WE WL LOSE OUR
HEATING...AND XPCT A DOWNWARD TREND TO THE STORMS.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
WL STILL HV LEE TROF AND AN UNSTBL AMS MON. HWVR...FORCING FOR
PCPN WL BE LACKING. STILL XPCT SCT STORM DVLPMNT DURING THE
MIDDAY...WHICH WL BE DROPPING INTO THE LEE TROF DURING THE AFTN.
THE RELATIVE LACK OF ACTIVITY AND CLEARING SKIES FROM WEST-TO-
EAST WILL ALLOW TEMPS TO CLIMB BACK INTO THE U80S AND SOME L90S
FOR THE AREA ON MON AFTN...W/ DEWPOINTS STANDING PAT IN THE
U60S/L70S - ANOTHER MUGGY DAY FOR THE AREA.
WEAK RIDGING CROSSES THE CENTRAL MID-ATLANTIC MONDAY NIGHT INTO
TUESDAY...MAKING FOR A REPRIEVE IN THUNDERSTORMS FOR 12-18 HRS. WITH
THE BERMUDA HIGH IN PLACE...EXPECT TUESDAY TO HAVE THE HIGHEST
TEMPERATURE DAY SINCE JULY. MAX TEMPS LOW TO MID 90S ACROSS LOWER
ELEVATIONS.
THE NEXT COLD FRONT APPROACHES LATE TUESDAY AND CROSSES THAT NIGHT.
WITH PLENTY OF ENERGY FROM THE HOT DAY...EXPECT AT LEAST ISOLATED
SEVERE WEATHER...PARTICULAR FOR WRN ZONES THAT ARE PROGGED TO GET
THE EVENING ACTIVITY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE OVER THE CWA WILL MOVE OFFSHORE ALLOWING A COLD FRONT
FROM THE WEST TO ENTER THE CWA FRIDAY. ALTHOUGH PVA IS WEAK...
STALLED BOUNDARY AND MOISTURE WILL SUPPLY ACTIVE WEATHER INTO THE
WEEKEND.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDS ACRS THE TERMINALS TAFTN. SCTD-NMRS SHRA/TSRA HV DVLPD E
OF MRB BUT W OF THE REST OF THE AIRFIELDS. DUE TO XPCTD CVRG AND
TRACKABLE FEATURES...TAFS NOW HV EXPLICIT THUNDER MENTION. IN
ADDITION...HV TEMPO FOR MOST LKLY TIME FRAME...22Z-02Z. HV MVFR
VSBY AND G30 KT. IF FULL CNVCTV DVLPMNT REALIZED AND AN AIRFIELD
TAKES A DIRECT HIT...IFR FLGT CONDS AND HIER GUSTS PSBL.
SLY WINDS WILL PERSIST INTO MON...ALONG W/ A FEW HIT/MISS SHOWERS
AS WELL THRU MON EVE.
BRIEF HIGH PRESSURE/VFR TUESDAY ON A HOT DAY (MAX TEMPS IN THE MID
90S). SCATTERED STRONG THUNDERSTORMS TUESDAY NIGHT AS A WEAK COLD
FRONT CROSSES THE REGION. HIGH PRESSURE/VFR OUTSIDE OF POTENTIAL
MORNING FOG MID TO LATE WEEK.
&&
.MARINE...
SLY FLOW ACRS THE MARINE AREA SUN-MON. MDL SNDGS DEPICT G20 KT
PSBL TAFTN...WHICH BEING FULLY REALIZED ATTM. HV RAISED SCA INTO
THE EVNG ALL WATERS. SLY FLOW PTTN CONTS INTO MON...BUT WNDS SHUD
BE LIGHTER.
SUB SCA SWLY FLOW MONDAY NIGHT THROUGH TUESDAY. WEAK COLD FRONT
BRINGS WLY FLOW LATE TUESDAY NIGHT THROUGH WEDNESDAY. HIGH PRESSURE
OVERHEAD WEDNESDAY NIGHT AND THURSDAY.
&&
.TIDES/COASTAL FLOODING...
DEPARTURES ON THE UPR TIDAL POTOMAC RIVER AND MOST OF THE BAY
STILL HOVERING AROUND 1 FT. LWTV2/SLIM2 STILL ONLY 3/4 FT ABOVE
NORMAL. A GOOD SLY FLOW CONTS ON THE WATERS...SO DO NOT ANTICIPATE
DEPARTURES TO DECREASE MUCH TNGT. BASED ON THESE TRENDS...
ANNAPOLIS WL EXCEED MINOR CRITERIA...AND SVRL OTHER SITES WL REACH
CAUTION STAGE. HV ISSUED COASTAL FLOOD ADVY FOR AA COUNTY...AND
MONITOR THE REST.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...COASTAL FLOOD ADVISORY FROM 9 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR MDZ014.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR
ANZ530>533-536>542.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ534-
543.
&&
$$
SYNOPSIS...BAJ
NEAR TERM...HTS
SHORT TERM...HTS/GMS
LONG TERM...CEM
AVIATION...HTS/BAJ
MARINE...HTS/BAJ
TIDES/COASTAL FLOODING...HTS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1018 AM EDT SUN AUG 31 2014
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL PERSIST THROUGH TUESDAY WITH AN ACTIVE
PATTERN FOR THE EASTERN SEABOARD. A WEAK COLD FRONT WILL CROSS THE
AREA TUESDAY NIGHT...FOLLOWED BY HIGH PRESSURE.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIPRES OFF THE EAST COAST OF THE CONUS THIS MRNG. THE ERN SEABOARD
W/IN WARM/HUMID S/SWLY FLOW...AHD OF A CDFNT ACRS SRN CNDA.
STLT/WATER VAPOR IMGRY DEPICT A STREAM OF MSTR AHD OF THE
CDFNT...EMINATING FM THE GLFMEX UP ALONG THE APLCHNS TO THE UPR
OHVLY/ERN GRTLKS. PWAT W/IN THIS ZONE AOA 2 INCHES.
MRNG LWX RAOB DEPICTS AN INVSN ARND H9...BUT A VERY UNSTBL
ENVIRONMENT ABV THAT. DAYTIME HEATING SHUD BE ABLE TO ERODE THE
INVSN...BUT WL AT LEAST HOLD THINGS IN CHECK FOR A LTL WHILE. A
PIECE OF ENERGY HAS BKN OFF FM MAIN STREAM...PROVIDING SHRA TO THE
PTMC HIGHLANDS. RECENT HRRR RUNS SUGGEST THIS WL MAKE IT TO THE
CATOCTINS BEFORE DSPTG...LKLY A RESULT OF THE INVSN. WHILE FULL
SUN TEMPS IN THE MID 90S...ADVANCING CLDCVR LKLY WL KEEP MAXT LWR
THAN THAT. UPDTD TEMPS TO LTST LAMP SINCE POTL CERTAINLY THERE FOR
TEMPS HIER THAN MID-UPR 80S.
USING A TEMP OF 90F AND DEWPTS IN THE LWR 70S...SHUD HV 2000-2500
J/KG CAPE BY LT DAY. BUT...FORCING WL COME IN THE WAY OF PVA/MID
LVL 20-30 KT FLOW...AND THAT WL HOLD OFF TIL AFTR 18Z FOR THE
MTNS...AND CLSR TO 00Z FOR THE CSTL PLAIN. ALSO NEED TO BE MINDFUL
OF THE DIFF HTG BNDRY...WHICH CUD BE ANTHR SOURCE OF INITIATION.
CERTAINLY HV THE DOWNDRAFT POTL FOR STRONG STORMS TDA...BUT DONT
THINK WE/LL BE ABLE TO ACHIEVE FULL POTL. CANNOT RULE OUT LCL WET
MICROBURSTS...BUT BELIEVE THEY WL BE HIT-OR-MISS IN NATURE.
AMPLE MSTR WL ALSO LEAD TO HVY RAINERS...THE OTHER THREAT THIS PM.
RAFL RATES WL BE SUFFICIENT TO LEAD TO A LCL FLASH FLOOD THREAT...
SPCLY UNDER TRAINING CELLS.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
AFTER THE EVE CONVECTION HAS DISSIPATED OFF AND MOVED EAST...
ANOTHER REGIONAL BATCH OF LIGHT/MOD RANGE IS TAGGED BY NEAR TERM
GUIDANCE AS MOVING ALONG THE MASON-DIXON LINE AS WELL - KEEPING
PRECIP CHANCES ALIVE INTO EARLY MON. AS THE BACK END OF THIS
FEATURE PASSES BY TO THE NORTH...PRECIP CHANCES WILL REMAIN IN THE
LOW CHANCE RANGE THRU MON AFTN/EVE ACROSS THE ERN HALF OF THE CWA
BUT MAINLY OF A LIGHT/SCTD NATURE...OUTSIDE OF A FEW TSTMS. THE
RELATIVE LACK OF ACTIVITY AND CLEARING SKIES FROM WEST-TO-EAST
WILL ALLOW TEMPS TO CLIMB BACK INTO THE U80S AND SOME L90S FOR THE
AREA ON MON AFTN...W/ DEWPOINTS STANDING PAT IN THE U60S/L70S -
ANOTHER MUGGY DAY FOR THE AREA.
WEAK RIDGING CROSSES THE CENTRAL MID-ATLANTIC MONDAY NIGHT INTO
TUESDAY...MAKING FOR A REPRIEVE IN THUNDERSTORMS FOR 12-18 HRS. WITH
THE BERMUDA HIGH IN PLACE...EXPECT TUESDAY TO HAVE THE HIGHEST
TEMPERATURE DAY SINCE JULY. MAX TEMPS LOW TO MID 90S ACROSS LOWER
ELEVATIONS.
THE NEXT COLD FRONT APPROACHES LATE TUESDAY AND CROSSES THAT NIGHT.
WITH PLENTY OF ENERGY FROM THE HOT DAY...EXPECT AT LEAST ISOLATED
SEVERE WEATHER...PARTICULAR FOR WRN ZONES THAT ARE PROGGED TO GET
THE EVENING ACTIVITY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE BUILDS IN BEHIND WITH CONTINENTAL AIR (NOT CANADIAN)
SO TEMPERATURE REMAIN ABOVE NORMAL. EXPECT MAX TEMPS AROUND 90F
WEDNESDAY THROUGH FRIDAY. RETURN FLOW AND ACTIVE WEATHER RETURNS
LATE FRIDAY INTO THE WEEKEND.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
MRNG FLGT RESTRICTIONS HV CLRD ACRS THE TERMINALS. SCTD SHRA/TSRA
XPCTD TO DVLP LATER TDA INTO THIS EVNG. LCL IFR PSBL. SCT NATURE
OF THE THREAT LENDS TO VCTS IN TAF ATTM. MORE SPECIFIC
RESTRICTIONS WL BE PLACED INTO FCST WHEN/WHERE APPROPRIATE.
SLY WINDS WILL PERSIST INTO MON...ALONG W/ A FEW HIT/MISS SHOWERS
AS WELL THRU MON EVE.
BRIEF HIGH PRESSURE/VFR TUESDAY ON A HOT DAY (MAX TEMPS IN THE MID
90S). SCATTERED STRONG THUNDERSTORMS TUESDAY NIGHT AS A WEAK COLD
FRONT CROSSES THE REGION. HIGH PRESSURE/VFR OUTSIDE OF POTENTIAL
MORNING FOG MID TO LATE WEEK.
&&
.MARINE...
SLY FLOW ACRS THE MARINE AREA SUN-MON. GUSTS TAFTN WL APPROACH SCA
LIMITS. AM CONSIDERING POSTING ADVY FOR THE AFTN-EVNG. FLOW PTTN
CONTS INTO MON.
SUB SCA SWLY FLOW MONDAY NIGHT THROUGH TUESDAY. WEAK COLD FRONT
BRINGS WLY FLOW LATE TUESDAY NIGHT THROUGH WEDNESDAY. HIGH PRESSURE
OVERHEAD WEDNESDAY NIGHT AND THURSDAY.
&&
.TIDES/COASTAL FLOODING...
DEPARTURES ON THE UPR TIDAL POTOMAC RIVER AND MOST OF THE BAY
HOVERING AROUND 1 FT. LWTV2/SLIM2 ONLY 3/4 FT ABOVE NORMAL. BASED
ON CURRENT TRENDS...THE CURRENT TIDE CYCLE WILL NOT CAUSE
ISSUES...ALTHOUGH ITS MIGHTY CLOSE TO ADVY AT ANNAPOLIS.
WINDS WILL REMAIN SLY THRU THE DAY. THE PM TIDE IS THE HIGHER ONE
ASTRONOMICALLY...SO WL NEED TO CONSIDER ADVYS. WL CONT TO MONITOR.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BAJ
NEAR TERM...HTS
SHORT TERM...GMS
LONG TERM...BAJ
AVIATION...HTS/GMS/BAJ
MARINE...HTS/GMS/BAJ
TIDES/COASTAL FLOODING...HTS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1158 PM EDT MON SEP 1 2014
.AVIATION...
//DISCUSSION...
WIDELY SCATTERED SHOWERS WILL FUNNEL INTO AREA OVERNIGHT AND
EVENTUALLY FOCUS OVER THE SOUTHERN CWA LATE TONIGHT INTO EARLY
TUESDAY AS A SECONDARY SHORTWAVE TROUGH SHIFTS THROUGH THE AREA FROM
THE SOUTHERN STREAM. THIS ACTIVITY WILL BRUSH THE I 94 TERMINALS WITH
SCATTERED...BUT SOMEWHAT PERSISTENT...ACTIVITY AROUND DAYBREAK. TO
THE NORTH...ISOLATED SHRAS WILL REMAIN HIT/MISS INTO PARTS OF THE
OVERNIGHT HOURS. SOME PATCHY FOG/STRATUS WITH IFR/MVFR CONDITIONS
WILL ALSO BE POSSIBLE AS LOW LEVEL MOISTURE REMAINS ELEVATED. THAT
SAID...A GENERAL INCREASE IN MID/UPPER CLOUDINESS WITH APPROACHING
WAVE WILL LIMIT THIS PROCESS TO SOME EXTENT. BY MID/LATE MORNING
TUESDAY...EXPECT VFR CONDITIONS AS DRIER AIR WORKS INTO THE AREA.
//DTW THRESHOLD THREATS...
* LOW CONFIDENCE THAT A THUNDERSTORM WILL IMPACT THE TERMINAL LATE
TONIGHT INTO TUESDAY MORNING.
* LOW CONFIDENCE IN CEILINGS BELOW 5000 FEET LATE TONIGHT INTO EARLY
TUESDAY.
&&
.PREV DISCUSSION...ISSUED 244 PM EDT MON SEP 1 2014
SHORT TERM...THIS EVENING AND TONIGHT
18Z SPECIAL CONFIRMS THE WARMER COLUMN DEPICTED BY THE RAP AND THEN
SOME. 900MB INVERSION IS QUITE A BIT MORE ROBUST THAN DEPICTED BY
THE GUIDANCE AS IS THE 600MB CAP. THUS, EVEN THE MOST TAME
DEPICTIONS OF CONVECTION IN THE NWP ARE LIKELY TOO AGGRESSIVE AND
CONCERNS REGARDING CAPPING NOTED IN THE MORNING UPDATE ARE
CONFIRMED. UPDRAFTS WILL STRUGGLE ACROSS MOST OF THE CWA WITH THE
EXCEPTION OF LOCATIONS NORTH OF I-69 AND ESPECIALLY WEST OF US-23
WHERE MID-LEVEL COOLING AND FORCING WILL BE MAXIMIZED. WITH THE LINE
ALREADY MARCHING TOWARD THIS AREA, EXPECT THAT THE ABUNDANCE OF
MID-LEVEL DRY AIR AND UNIDIRECTIONAL FLOW ABOVE 1.5KM WILL SUPPORT
BOWING SEGMENTS CARRYING A LOW-END SEVERE WIND THREAT. IN ADDITION,
ISOLATED TORNADO THREAT OUTLINED IN THE EARLIER UPDATE REMAINS IN
TACT. FOR REMAINING AREAS, EXPECT NOTHING MORE THAN A GUST TO 40
MPH. IN ADDITION, BACKED OFF ON POPS AS EARLIER SUSPICIONS REGARDING
COVERAGE POTENTIAL STILL LOOM.
A WEAK COLD FRONT WILL SAG THROUGH THE AREA TONIGHT. FRONTAL
INVERSION WILL PROMOTE EXPANSION OF STRATUS LATE TONIGHT, BUT EXPECT
THAT MOISTURE WILL BE TOO SHALLOW AND FORCING TOO WEAK TO SUPPORT
ANY LEGITIMATE COVERAGE OR INTENSITY OF SHOWERS. WITH UPPER SUPPORT
IN THE FORM OF A SHEARING SHORTWAVE NOT SCHEDULED TO ARRIVE UNTIL
TUESDAY MORNING PER 12Z GUIDANCE, AND MAINLY SOUTH OF THE AREA AT
THAT, NOTHING MORE THAN A CHC POP IS WARRANTED ATTM.
LONG TERM...TUESDAY THROUGH NEXT MONDAY
A COLD FRONT WILL BE SOUTHEAST OF THE CWA TO START OUT TUESDAY
MORNING. HOWEVER A MID LEVEL SHORTWAVE RIDING NORTHEAST ALONG THE
FRONT WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE
AREA TUESDAY MORNING. AFTER THE SHORTWAVE TRACKS OFF TO THE
NORTHEAST SIGNIFICANT DRYING WILL TAKE PLACE AS A SLUG OF 30 PERCENT
RELATIVE HUMIDITY AT 700 MB ADVECTS IN FROM THE WEST...ENDING RAIN
CHANCES QUICKLY EARLY TUESDAY AFTERNOON. WHILE THERE IS STILL SOME
UNCERTAINTY REGARDING HOW FAR WEST THE RAIN WILL FALL GIVEN THE PUSH
OF DRY AIR ADVECTING IN...THE LATEST SUITE OF MODELS HAS THE DRIER
AIR PUSHING IN A BIT SOONER THAN THE 00Z RUNS. THEREFORE WILL NUDGE
THE FORECAST A BIT DRIER TUESDAY AFTERNOON FROM THE PREVIOUS
FORECAST. DESPITE THE PASSAGE OF A COLD FRONT THERE ISN`T A LARGE
PUSH OF COLD AIR ASSOCIATED WITH IT...MEANING DAYTIME HIGHS ARE
EXPECTED TO GET AROUND 80 TUESDAY AFTERNOON BEHIND THE FRONT.
RIDGING WILL KEEP THE FORECAST DRY THROUGH WEDNESDAY AS REBOUNDING
HEIGHTS ALLOW DAYTIME HIGHS TO GET BACK INTO THE LOWER 80S BY
WEDNESDAY AFTERNOON.
MOISTURE SURGE FROM THE GULF OF MEXICO COMMENCES ON THURSDAY AS A
LOW CHANCE FOR CONVECTION EXISTS WITHIN THE WARM SECTOR OF A
REGION-WIDE LOW PRESSURE SYSTEM. BEST CHANCE FOR THUNDERSTORMS
/POSSIBLY SEVERE/ WILL BE FRIDAY AS WARM AND MOIST AIRMASS (85/70
T/TD) IS IN PLACE ALONG WITH FORECASTED CAPE OF 3000 J/KG. BULK
SHEAR INCREASES TO NEAR 30 KT IN THE 1-6 KM LAYER AS WELL. THESE
INGREDIENTS WILL BE IN PLACE AS A RAGGED COLD FRONT CROSSES THE
STATE. THIS BRINGS A TRIPLE THREAT OF SEVERE WEATHER WITH
WIND...HAIL...AND ISOLATED TORNADOES ALL POSSIBLE
MARINE...
SHOWERS AND THUNDERSTORMS WILL TRACK THROUGH THE CENTRAL GREAT LAKES
TONIGHT AS A COLD FRONT MOVES THROUGH LAKE HURON AND LOWER MICHIGAN.
SOME OF THESE STORMS MAY BE SEVERE...MAINLY ACROSS THE NORTHERN
PORTION OF LAKE HURON. HIGH PRESSURE WILL BUILD INTO THE REGION
BEHIND THIS FRONT ON TUESDAY...WHICH WILL REMAIN IN CONTROL OF THE
WEATHER THROUGH THURSDAY...PROVIDING FAVORABLE BOATING CONDITIONS.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....DG
SHORT TERM...JVC
LONG TERM....KURIMSKI/MM
MARINE.......KURIMSKI
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
645 PM EDT SUN AUG 31 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014
A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014
THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.
ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.
&&
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014
MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.
LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK. THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION. IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS. THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT. IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.
THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS. MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND. H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT. THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 645 PM EDT SUN AUG 31 2014
SCATTERED SHOWERS MAY AFFECT OUR SOUTHEAST TERMINALS (KLAN AND
PERHAPS KBTL/KJXN) DURING THE EARLY TO MID EVENING HOURS TONIGHT
BEFORE DISSIPATING. MAINLY VFR CONDITIONS ARE ANTICIPATED OVERNIGHT
BUT SOME PATCHY MVFR CONDITIONS MAY DEVELOP DURING THE EARLY MORNING
HOURS MONDAY DUE TO LOW CLOUDS AND/OR FOG. CONDITIONS SHOULD THEN
GRADUALLY DETERIORATE TO MAINLY MVFR MONDAY MORNING DUE TO LOW
CLOUDS AND PATCHY FOG.
BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL INCREASE WITH
GUSTS AROUND 20 TO 25 KTS. SCATTERED THUNDERSTORMS WILL ALSO DEVELOP
FROM LATE MONDAY MORNING THROUGH MONDAY AFTERNOON AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT. SCATTERED SHOWERS AND
THUNDERSTORMS WILL LINGER MONDAY EVENING.
&&
.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014
BEACH HAZARDS AND SCA ISSUED FOR MONDAY
&&
.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014
HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
EVENING FOR MIZ037-043-050-056-064-071.
LM...SMALL CRAFT ADVISORY FROM 10 AM TO 10 PM EDT MONDAY FOR
LMZ844>849.
&&
$$
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...LAURENS
HYDROLOGY...MJS
MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
330 PM EDT SUN AUG 31 2014
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/MARINE
.SYNOPSIS...
ISSUED AT 322 PM EDT SUN AUG 31 2014
A WEAK AREA OF HIGH PRESSURE WILL KEEP MUCH OF THE REGION DRY INTO
THE EVENING. A COLD FRONT WILL APPROACH FROM THE WEST ON LABOR DAY
TRIGGERING SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL RETURN
FOR TUESDAY DRYING THE REGION OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 322 PM EDT SUN AUG 31 2014
THE MAIN CHALLENGE IN THE SHORT TERM DEALS WITH THE POTENTIAL FOR
SEVERE WEATHER ON MONDAY. OVERALL THE POTENTIAL STILL EXISTS.
ONE POTENTIAL LIMITING FACTOR WILL BE WHAT IMPACTS THE DECAYING
AREA OF THUNDERSTORMS WILL HAVE AS IT MOVES IN FROM THE WEST
MONDAY MORNING. THE HRRR RUC SHOWS THIS SYSTEM WEAKENING WELL
BEFORE IT ARRIVES IN MI...SO I AM THINKING THIS WILL HAVE A
MINIMAL IMPACT ON THE POTENTIAL INSTABILITY MONDAY. THE
COMBINATION OF HEATING AND MOISTURE ADVECTION SUPPORTS CAPE OVER
1500 J/KG ON MONDAY. DEEP LAYER SHEAR INCREASES TOWARD 18Z AS THE
MID LEVEL WAVE CURRENTLY IN WI ARRIVES IN NW LOWER. THE LIFT
ASSOCIATED WITH THIS FEATURE SHOULD TRIGGER STORMS. THE SHEAR WILL
HELP TO INCREASE THE POTENTIAL FOR ORGANIZED CONVECTION AND
RESULTING SEVERE WEATHER. DAMAGING WINDS AND LARGE HAIL A THREAT.
SRH VALUES AROUND 200 M2/S2 DO SUPPORT A RISK FOR TORNADOES.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 322 PM EDT SUN AUG 31 2014
MEDIUM RANGE MODELS ARE IN DECENT AGREEMENT INTO NEXT WEEKEND...
HOWEVER THERE ARE TIMING DIFFERENCES WITH A STRONG COLD FRONT THAT
COMES THROUGH FRIDAY/FRIDAY NIGHT.
LARGE HIGH PRESSURE IS EXPECTED TO BE SITTING OVER THE EAST SEABOARD
BY MID WEEK. THIS WILL BRING WARMING SOUTHERLY FLOW TO THE GREAT
LAKES REGION. IT CONTINUES TO LOOK LIKE THURSDAY WILL BE THE
WARMEST DAY OF THE WEEK WITH 80S FOR HIGHS. THE RISK FOR SHOWERS
AND STORMS WILL INCREASE ON THURSDAY WITH A COLD FRONT MOVING INTO
THE WESTERN GREAT LAKES. WARM AND MOIST AIR WITH MOVE IN AHEAD OF
THIS FRONT. IF A LOW LEVEL JET COMES INTO PLAY WE COULD BE LOOKING
AT STRONG TO SEVERE STORMS TOWARD THE END OF THE DAY.
THERE CONTINUES TO BE TIMING DIFFERENCES WITH THE FRONT...BUT THE
GFS SLOWED THE FRONT DOWN...CLOSER TO THE WHAT THE ECMWF HAS SHOWN.
THEREFORE BELIEVE THE FRONT WILL BE COMING THROUGH ON FRIDAY WITH
ADDITIONAL CHANCES FOR SHOWERS AND STORMS. MUCH COOLER AIR FOLLOWS
THIS STRONG FRONT FOR FRIDAY NIGHT AND INTO NEXT WEEKEND. H8 TEMPS
DROP TO +7 TO +10C AS COMPARED TO AROUND +19C AHEAD OF THE COLD
FRONT. THE WEEKEND SHOULD FEATURE HIGHS IN THE UPPER 60S TO MID 70S
WITH MAINLY DRY WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 134 PM EDT SUN AUG 31 2014
CEILINGS WERE TRENDING TOWARD VFR EARLY THIS AFTERNOON...HOWEVER
SOME MVFR MAY HOLD ON UNTIL ABOUT 20Z. OTHERWISE THE VFR AND LIGHT
WINDS WILL BE MAINTAINED INTO AND THROUGH MUCH OF THE OVERNIGHT. I
HAVE INTRODUCED SOME MVFR CEILINGS RETURNING AROUND DAYBREAK
MONDAY DUE TO MOIST LOW LEVELS AND DIURNAL TRENDS.
THEN BY LATE MONDAY MORNING/EARLY AFTERNOON SSW WINDS WILL
INCREASE WITH GUSTS AROUND 20 KNOTS. ALSO IN THIS TIME FRAME
WIDELY SCATTERED THUNDERSTORMS MAY BEGIN TO DEVELOP AS INSTABILITY
INCREASES AHEAD OF AN APPROACHING COLD FRONT.
&&
.MARINE...
ISSUED AT 322 PM EDT SUN AUG 31 2014
BEACH HAZARDS AND SCA ISSUED FOR MONDAY
&&
.HYDROLOGY...
ISSUED AT 322 PM EDT SUN AUG 31 2014
HIGH PWAT VALUES SUPPORT LOCALLY HEAVY RAIN ON MONDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
EVENING FOR MIZ037-043-050-056-064-071.
LM...SMALL CRAFT ADVISORY FROM 10 AM TO 10 PM EDT MONDAY FOR
LMZ844>849.
&&
$$
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...JK
AVIATION...JK
HYDROLOGY...MJS
MARINE...MJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
224 PM EDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 514 AM EDT SUN AUG 31 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID LEVEL RIDGE FROM THE
UPPER MS VALLEY THROUGH WRN LAKE SUPERIOR BTWN A DEPARTING SHRTWV
TROUGH INTO NRN LOWER MI AND AN UPSTREAM SHRTWV OVER THE WRN
DAKOTAS. ISOLATED SHOWERS ASSOCIATED WITH THE COMMA HEAD OF THE MI
SHRTWV WERE EXITING THE ERN CWA. HOWEVER...EXTENSIVE LOW LEVEL
MOISTURE/LOW CLOUDS PERSISTED OVER MUCH OF UPPER MI...EXCEPT FROM
CMX/P59 TO IWD. AT THE SFC...A RIDGE EXTENDED FROM JAMES BAY AND NRN
ONTARIO INTO WRN UPPER MI AND NW WI.
TODAY...AS THE 850-700 MB MOISTURE DEPARTS THIS MORNING AND DAYTIME
HEATING/MIXING INCREASES...EXPECT THAT THE REMAINING CLOUDS OVER THE
CNTRL AND EAST WILL THIN OUT AND GIVE WAY TO SCT CU BY AFTERNOON.
WITH SUBSIDENCE LIMITING INVERSION HEIGHTS CLOSER TO 900 MB...MAX
TEMPS MAINLY IN THE MID 70S ARE IN STORE WITH SOME LOWER READINGS
NEAR THE GREAT LAKES WHERE E OR SSE WINDS PREVAIL.
TONIGHT...AS THE DAKOTAS SHORTWAVE AND ASSOCIATED SFC TROUGH
APPROACH THE REGION SRLY FLOW AND MOISTURE ADVECTION WILL INCREASE.
AS PWAT VALUES CLIMB INTO THE 1.5-2.0 INCH RANGE FROM NW WI TO NEAR
IWD AND LARGE SCALE LIFT INCREASES WITH UPPER LEVEL DIV 700-300 MB
QVECTOR CONV AHEAD OF THE MID LEVEL TROUGH...SHRA/TSRA THAT DEVELOP
OVER MN WILL SPREAD TOWARD AND INTO THE CWA...MAINLY AFT 06Z. WITH
THE INITIAL PUSH OF 850-700 MB THETA-E ADVECTION SOME ISOLD SHRA/TSRA
MAY ALSO SPREAD INTO N CNTRL UPPER MI DURING THE EVENING...BUT
CONFIDENCE INTO CNTRL UPPER MI IS LOW WITH ONLY SLIGHT CHANCE POPS
MENTIONED. THE BEST CHANCE FOR SVR STORMS IS EXPECTED TO REMAIN WEST
OF THE CWA...CLOSER TO THE GREATER INSTABILITY. HOWEVER...WITH
MUCAPE VALUES TO AT LEAST 1K J/KG AND FAVORABLE 0-1KM/0-6KM SHEAR
TO 30/40 KNOTS...SOME STRONG STORMS WILL BE POSSIBLE WITH GUSTY
WINDS AND SMALL HAIL. THE MAIN HAZARD WITH TSRA LATE TONIGHT WILL BE
LOCALLY HEAVY RAIN WITH SOME ISOLD 1-2 INCH AMOUNTS POSSIBLE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 224 PM EDT SUN AUG 31 2014
ASIDE FROM SOME MINOR PRECIP AMOUNTS POSSIBLE EARLY IN THE NIGHT
OVER FAR ERN UPPER MI DUE TO THE MON COLD FRONT EXITING THE
AREA...MON NIGHT AND TUE LOOK DRY FOR THE MOST PART AS SFC RIDGING
MOVES IN. A COUPLE MODELS SHOW A FEW HUNDREDTHS OF AN INCH OF QPF
TUE AFTERNOON AS A SHORTWAVE MOVES THROUGH THE REGION...BUT FORECAST
SOUNDINGS ARE JUST TOO DRY AND THE SHORTWAVE LOOKS TO GO TOO FAR SE
OF THE AREA TO HAVE PRECIP IN THE FORECAST. WILL KEEP A DRY
FORECAST. HIGH TEMPS LOOK TO BE FROM THE UPPER 60S TO MID 70S AS
850MB TEMPS WILL BE 9-11C.
FOR WED...SFC RIDGING MOVES E...SO SLY LOW LEVEL FLOW WILL BE ON THE
INCREASE UNDER ZONAL UPPER FLOW. MODELS SHOW VERY SUBTLE SHORTWAVE
ENERGY MOVING THROUGH THE AREA WED. OF COURSE...THIS FAR OUT THE
CONFIDENCE OF PRECIP RESULTING FROM WEAK SHORTWAVES IS MINIMAL...SO
WILL HAVE SLIGHT CHANCE POPS AT BEST.
FOR WED NIGHT THROUGH FRI NIGHT...MODELS TEND TO GENERALLY AGREE
THAT A STRONGER SHORTWAVE WILL MOVE INTO THE NCENTRAL CONUS AND
EVENTUALLY ACROSS OR NEAR THE CWA LATE FRI INTO FRI NIGHT. WHILE THE
ECMWF HAS SHOWN BETTER RUN TO RUN CONTINUITY WITH THE SHORTWAVE AND
RESULTING SFC LOW...THE UPPER LEVEL ENERGY IS CURRENTLY OVER THE
SEWARD PENINSULA OF ALASKA AND WILL ONLY ENTER THE CONUS OVER WA TUE
NIGHT. SHORTWAVE ENERGY THAT HAS YET TO REALLY DETACH FROM THE
PARENT UPPER LEVEL LOW OVER ALASKA NORMALLY LEADS TO PRETTY LOW
CONFIDENCE IN TIMING/TRACK 4-5 DAYS OUT...WHICH IS THE CASE HERE. DO
HAVE TO PREFER THE ECMWF SINCE IT HAS BEEN MORE STEADY FROM RUN TO
RUN...BUT CONFIDENCE IS STILL LOW SINCE THE GFS IS AROUND 18 HOURS
SLOWER AND FARTHER S WITH THE PASSAGE OF THE RESULTING SFC LOW THAN
THE ECMWF. OVERALL CONFIDENCE IN RAIN SOMEWHERE IN THE THU-FRI TIME
SPAN IS GOOD ENOUGH FOR HIGH CHANCE POPS...BUT TIMING WILL NEED TO
BE REFINED OVER THE NEXT FEW FORECASTS. AT THIS TIME...THE BEST
CHANCES FOR STRONG TO SEVERE STORMS /USING THE PREFERRED TIMING AND
TRACK OF THE ECMWF/ IS WED NIGHT INTO THU MORNING ALONG THE WARM
FRONT WHERE ELEVATED STORMS WOULD BE POSSIBLE...AND AGAIN LATE THU
INTO THU NIGHT AS MLCAPES APPROACH 3000J/KG WITH 0-6KM SHEAR OF
40-50KTS AND 0-1KM SHEAR AROUND 30KTS ALONG AND AHEAD OF THE COLD
FRONT. WHILE ALL MODES OF SEVERE WEATHER WOULD BE POSSIBLE WITH THE
ECMWF SOLUTION LATE THU INTO THU NIGHT...IT IS ALSO THE WORST CASE
SCENARIO. THE FARTHER S GFS WOULD RESULT IN MORE CLOUDS ON FRI
BEFORE THE SFC LOW AND COLD FRONT MOVE THROUGH...SO INSTABILITY
WOULD NOT BE AS STRONG. WILL NEED TO MONITOR AS CONFIDENCE IN SEVERE
CHANCE ARE LIMITED AND MODEL GUIDANCE WILL LIKELY CHANGE. FARTHER N
ECMWF IS ALSO WARMEST WITH 850MB TEMPS RISING TO AROUND 20C THU
AFTERNOON...WHICH WOULD RESULT IN HIGH TEMPS WELL INTO THE 80S OR
EVEN LOW 90S DEPENDING ON CLOUD AND PRECIP COVERAGE. WILL GO WITH A
MORE CONSENSUS APPROACH TO TEMPS GIVEN UNCERTAINTY.
NEXT WEEKEND LOOKS DRY AS COOLER HIGH PRESSURE SETTLES IN BEHIND THE
PREVIOUS SYSTEM. 850MB TEMPS FALL TO 3-4C ON SAT AND WARM TO 6-8C ON
SUN...SO COOLER CONDITIONS WITH HIGHS IN THE 60S TO LOW 70S ARE
EXPECTED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1206 PM EDT SUN AUG 31 2014
EXPECT LINGERING SC IFR CIGS AT CMX AND SAW TO DISSIPATE WITH MIXING
EARLY THIS AFTERNOON. OTHERWISE...VFR CONDITIONS WILL CONTINUE UNTIL
LATE TONIGHT INTO MON MORNING AS NEXT SYSTEM AND RAIN ARRIVES BY
THEN FOR IWD AND CMX. SAW IS A DIFFERENT STORY AS THERE IS A
POTENTIAL OF AN UPSLOPE LOW CLOUD/FOG EVENT FROM LAKE MICHIGAN WITH
SOUTH WINDS AND PUT THAT SCENARIO OF LIFR/IFR CONDITIONS WITH FOG
AND LOW CLOUDS THERE TONIGHT. ON MON MORNING...RAIN WILL HAVE
STARTED AND IFR/LIFR CONDITIONS FOR ALL SITES WILL PREVAIL. LLJ SETS
UP TONIGHT OFF THE SFC AT ALL SITES AND PUT IN LLWS TO COVER IT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 514 AM EDT SUN AUG 31 2014
WINDS WILL BE LESS THAN 20 KTS OR LESS THROUGH MOST OF THE PERIOD
EXCEPT FOR A PERIOD OF SE TO S GUSTS OF 20 TO 30 KNOTS TONIGHT AND
MONDAY MORNING. WINDS WILL THEN VEER WRLY TO 20 KNOTS MON AFTERNOON
AND MON NIGHT IN THE WAKE OF A LOW PRESSURE SYSTEM AND COLD FRONT.
WIDESPREAD FOG WILL CONTINUE THROUGH THIS MORNING AND THEN DEVELOP
AGAIN TONIGHT INTO MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1207 PM EDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 514 AM EDT SUN AUG 31 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID LEVEL RIDGE FROM THE
UPPER MS VALLEY THROUGH WRN LAKE SUPERIOR BTWN A DEPARTING SHRTWV
TROUGH INTO NRN LOWER MI AND AN UPSTREAM SHRTWV OVER THE WRN
DAKOTAS. ISOLATED SHOWERS ASSOCIATED WITH THE COMMA HEAD OF THE MI
SHRTWV WERE EXITING THE ERN CWA. HOWEVER...EXTENSIVE LOW LEVEL
MOISTURE/LOW CLOUDS PERSISTED OVER MUCH OF UPPER MI...EXCEPT FROM
CMX/P59 TO IWD. AT THE SFC...A RIDGE EXTENDED FROM JAMES BAY AND NRN
ONTARIO INTO WRN UPPER MI AND NW WI.
TODAY...AS THE 850-700 MB MOISTURE DEPARTS THIS MORNING AND DAYTIME
HEATING/MIXING INCREASES...EXPECT THAT THE REMAINING CLOUDS OVER THE
CNTRL AND EAST WILL THIN OUT AND GIVE WAY TO SCT CU BY AFTERNOON.
WITH SUBSIDENCE LIMITING INVERSION HEIGHTS CLOSER TO 900 MB...MAX
TEMPS MAINLY IN THE MID 70S ARE IN STORE WITH SOME LOWER READINGS
NEAR THE GREAT LAKES WHERE E OR SSE WINDS PREVAIL.
TONIGHT...AS THE DAKOTAS SHORTWAVE AND ASSOCIATED SFC TROUGH
APPROACH THE REGION SRLY FLOW AND MOISTURE ADVECTION WILL INCREASE.
AS PWAT VALUES CLIMB INTO THE 1.5-2.0 INCH RANGE FROM NW WI TO NEAR
IWD AND LARGE SCALE LIFT INCREASES WITH UPPER LEVEL DIV 700-300 MB
QVECTOR CONV AHEAD OF THE MID LEVEL TROUGH...SHRA/TSRA THAT DEVELOP
OVER MN WILL SPREAD TOWARD AND INTO THE CWA...MAINLY AFT 06Z. WITH
THE INITIAL PUSH OF 850-700 MB THETA-E ADVECTION SOME ISOLD SHRA/TSRA
MAY ALSO SPREAD INTO N CNTRL UPPER MI DURING THE EVENING...BUT
CONFIDENCE INTO CNTRL UPPER MI IS LOW WITH ONLY SLIGHT CHANCE POPS
MENTIONED. THE BEST CHANCE FOR SVR STORMS IS EXPECTED TO REMAIN WEST
OF THE CWA...CLOSER TO THE GREATER INSTABILITY. HOWEVER...WITH
MUCAPE VALUES TO AT LEAST 1K J/KG AND FAVORABLE 0-1KM/0-6KM SHEAR
TO 30/40 KNOTS...SOME STRONG STORMS WILL BE POSSIBLE WITH GUSTY
WINDS AND SMALL HAIL. THE MAIN HAZARD WITH TSRA LATE TONIGHT WILL BE
LOCALLY HEAVY RAIN WITH SOME ISOLD 1-2 INCH AMOUNTS POSSIBLE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 433 AM EDT SUN AUG 31 2014
UPPER LEVELS FEATURE TROUGHING OVER THE CENTRAL CONUS TO BEGIN THE
PERIOD BUT THAT GIVES WAY TO SHALLOW RIDGING BY MID WEEK. SHORTWAVE
TROUGH MOVES FROM ROCKIES TO CENTRAL CANADA BY LATE THIS WEEK...WITH
WARM SW FLOW ALOFT STREAMING ACROSS THE GREAT LAKES. COLD FRONT MOVES
THROUGH AROUND FRIDAY WITH SFC RIDGE AND DRY/COOLER AIR SETTLING
OVER UPPER GREAT LAKES BY NEXT WEEKEND. CHANCES FOR SHRA/TSRA ON
LABOR DAY AS STRONG SHORTWAVE AND COLD FRONT CROSS UPPER GREAT
LAKES. THERE WILL BE ADDITIONAL CHANCES FOR SHRA AND TSRA AHEAD AND
ALONG THE LATE WEEK COLD FRONT AS WELL. EXPECT TEMPS FOR THE MOST
PART TO BE ABOVE NORMAL THROUGH THE WEEK. TEMPS PROBABLY WILL NOT
FALL BLO NORMAL UNTIL NEXT WEEKEND IN WAKE OF THE COLD FRONT PASSAGE
ON FRIDAY.
THUNDER CHANCES AND STRENGTH ON LABOR DAY AND AGAIN WEDNESDAY NIGHT
THROUGH FRIDAY LOOKS TO BE THE HIGHEST IMPACT WEATHER THIS WEEK.
LABOR DAY...INITIAL SHORTWAVE CURRENTLY DRIVING SHRA/TSRA OVER THE
DAKOTAS LIFTS OVER ONTARIO TO START THE DAY WHILE ANOTHER SHORTWAVE
CURRENTLY OVER OREGON/IDAHO TRACKS TOWARD WESTERN GREAT LAKES. MAIN
SFC LOW WILL BE NORTH OF LK SUPERIOR CLOSER TO LEADING SHORTWAVE. SFC
TROUGH WILL EXTEND SOUTH ACROSS UPPER GREAT LAKES REGION AND ON INTO
THE SOUTHERN PLAINS. H85-H5 Q-VECTOR CONVERGENCE MOSTLY IMPACTS CWA
IN THE MORNING. MOISTURE TRANSPORT AT H85-H7 IS MAXIMIZED AHEAD OF
THE FRONT IN THE MORNING AS WELL. THERE WILL BE SOME RISK FOR
STRONGER STORMS AS DURING THIS PERIOD OF FORCING/LIFT THERE IS A H85
JET UP TO 50 KTS FM THE SOUTHWEST/0-6KM SHEAR OVER 40 KTS AND 1-6KM
MUCAPES UP TO 500 J/KG. FREEZING LEVEL IS BTWN 12-13KFT WITH STORM
CORES HAVING TO REACH ABOVE 35 KFT FOR POTENTIAL OF ONE-INCH HAIL.
INSTABILITY WILL BE LIMITING FACTOR...BUT THERE MAY BE AT LEAST
ISOLATED STRONGER STORMS. BY AFTN...MLCAPES SPIKE UP WELL OVER 1000
J/KG ESPECIALLY CNTRL CWA...BUT SFC FRONT IS ON ITS WAY ACROSS CWA BY
THAT TIME AND LARGER SCALE SUBSIDENCE SHOULD BE DEVELOPING IN WAKE OF
SHORTWAVES MOVING THROUGH LATE TONIGHT INTO MONDAY MORNING. IF SFC
FRONT SLOWS UP...EVEN JUST SLIGHTLY...ISOLD STORMS MAY TRY TO DEVELOP
WITH THE INCREASING DAYTIME HEATING/INSTABILITY. RISK OF SEVERE STILL
THERE AS WELL WITH 0-6KM SHEAR 35-40 KTS. MAX TEMPS ON LABOR DAY
HIGHLY DEPEND ON EXTENT OF CLOUD COVER...BUT SEEMS THAT MANY AREAS
WILL SEE READINGS WELL INTO THE 70S. SOUTH WINDS MAY BE GUSTY OVER
EASTERN THIRD OF CWA...ESPECIALLY NEAR LK MICHIGAN SHORE.
FRONT CLEARS EASTERN CWA BY MONDAY EVENING WITH HIGH PRESSURE
SETTLING ACROSS FOR LATER MONDAY NIGHT INTO TUESDAY. ONSHORE WNW
WINDS WILL KEEP LK SUPERIOR SHORE COOLER ON TUESDAY IN THE MID-UPR
60S...BUT TEMPS SHOULD MAINLY BE IN THE LOWER 70S ELSEWHERE.
AS FLOW ALOFT BECOMES MORE ZONAL BY WEDNESDAY MAY START TO SEE
WEAKER SHORTWAVES WORK ACROSS UPR LAKES. GFS/GEM-NH AGGRESSIVE
WITH QPF ON WEDNESDAY BUT GFS SOUNDINGS INDICATE DEEPER MOISTURE IS
LACKING WITH ONLY WEAKER SHORTWAVES SHOWN. PREFER SLOWER ECMWF
SOLUTION SHOWING BETTER CHANCES OF SHRA/TSRA ARRIVING BY WEDNESDAY
NIGHT AS STRONGER SHORTWAVE ARRIVES. LAST FEW RUNS OF ECMWF ARE
SHOWING GREATER SIGNAL OF THIS OCCURRING. STRONG LOW-LEVEL MOISTURE
TRANSPORT AIMED INTO THE UPR LAKES ALONG WITH LARGE AREA OF ML
MUCAPES OVER 1000-1500 J/KG UPSTREAM WITH LIFT ENHANCED BY RIGHT
ENTRANCE REGION OF JET STREAK OVER ONTARIO/QUEBEC COULD RESULT IN AT
LEAST ISOLD STRONG ELEVATED STORMS WEDNESDAY NIGHT INTO THURSDAY
MORNING WITH ANOTHER ROUND OF STRONGER SFC BASED STORMS ALONG FRONTAL
BOUNDARY POSSIBLE LATER THURSDAY. LIMITING FACTOR FOR ADDITIONAL
STORMS LATER IN THE DAY WOULD BE NOT AS MUCH MOISTURE ALONG THE SFC
FRONT IN WAKE OF THE SHORTWAVE THAT MOVES THROUGH THURSDAY MORNING.
TEMPS AHEAD OF THE FRONT ON THURSDAY COULD GET QUITE WARM AS H85
TEMPS SURGE TOWARD +20C. WITH FULL SUNSHINE THIS WOULD SUPPORT HIGHS
INTO THE UPPER 80S IF NOT LOWER 90S. CURRENT FORECAST IS MORE TOWARD
CONSENSUS WITH UNCERTAINTY ON CLOUDS AND PRECIP CHANCES. WILL BE
SOMETHING THAT MAY NEED ADJUSTING IN LATER FORECASTS THOUGH.
THE FRONT...ALONG WITH SOME POTENTIAL FOR ADDITIONAL SHRA/TSRA...
SLIDES EAST AND SOUTH OF MOST CWA BY FRIDAY. HIGH PRESSURE MOVES
ACROSS FOR AT LEAST THE START OF NEXT WEEKEND WITH A MODEST COOLING
TREND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1206 PM EDT SUN AUG 31 2014
EXPECT LINGERING SC IFR CIGS AT CMX AND SAW TO DISSIPATE WITH MIXING
EARLY THIS AFTERNOON. OTHERWISE...VFR CONDITIONS WILL CONTINUE UNTIL
LATE TONIGHT INTO MON MORNING AS NEXT SYSTEM AND RAIN ARRIVES BY
THEN FOR IWD AND CMX. SAW IS A DIFFERENT STORY AS THERE IS A
POTENTIAL OF AN UPSLOPE LOW CLOUD/FOG EVENT FROM LAKE MICHIGAN WITH
SOUTH WINDS AND PUT THAT SCENARIO OF LIFR/IFR CONDITIONS WITH FOG
AND LOW CLOUDS THERE TONIGHT. ON MON MORNING...RAIN WILL HAVE
STARTED AND IFR/LIFR CONDITIONS FOR ALL SITES WILL PREVAIL. LLJ SETS
UP TONIGHT OFF THE SFC AT ALL SITES AND PUT IN LLWS TO COVER IT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 514 AM EDT SUN AUG 31 2014
WINDS WILL BE LESS THAN 20 KTS OR LESS THROUGH MOST OF THE PERIOD
EXCEPT FOR A PERIOD OF SE TO S GUSTS OF 20 TO 30 KNOTS TONIGHT AND
MONDAY MORNING. WINDS WILL THEN VEER WRLY TO 20 KNOTS MON AFTERNOON
AND MON NIGHT IN THE WAKE OF A LOW PRESSURE SYSTEM AND COLD FRONT.
WIDESPREAD FOG WILL CONTINUE THROUGH THIS MORNING AND THEN DEVELOP
AGAIN TONIGHT INTO MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
516 AM EDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 514 AM EDT SUN AUG 31 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID LEVEL RIDGE FROM THE
UPPER MS VALLEY THROUGH WRN LAKE SUPERIOR BTWN A DEPARTING SHRTWV
TROUGH INTO NRN LOWER MI AND AN UPSTREAM SHRTWV OVER THE WRN
DAKOTAS. ISOLATED SHOWERS ASSOCIATED WITH THE COMMA HEAD OF THE MI
SHRTWV WERE EXITING THE ERN CWA. HOWEVER...EXTENSIVE LOW LEVEL
MOISTURE/LOW CLOUDS PERSISTED OVER MUCH OF UPPER MI...EXCEPT FROM
CMX/P59 TO IWD. AT THE SFC...A RIDGE EXTENDED FROM JAMES BAY AND NRN
ONTARIO INTO WRN UPPER MI AND NW WI.
TODAY...AS THE 850-700 MB MOISTURE DEPARTS THIS MORNING AND DAYTIME
HEATING/MIXING INCREASES...EXPECT THAT THE REMAINING CLOUDS OVER THE
CNTRL AND EAST WILL THIN OUT AND GIVE WAY TO SCT CU BY AFTERNOON.
WITH SUBSIDENCE LIMITING INVERSION HEIGHTS CLOSER TO 900 MB...MAX
TEMPS MAINLY IN THE MID 70S ARE IN STORE WITH SOME LOWER READINGS
NEAR THE GREAT LAKES WHERE E OR SSE WINDS PREVAIL.
TONIGHT...AS THE DAKOTAS SHORTWAVE AND ASSOCIATED SFC TROUGH
APPROACH THE REGION SRLY FLOW AND MOISTURE ADVECTION WILL INCREASE.
AS PWAT VALUES CLIMB INTO THE 1.5-2.0 INCH RANGE FROM NW WI TO NEAR
IWD AND LARGE SCALE LIFT INCREASES WITH UPPER LEVEL DIV 700-300 MB
QVECTOR CONV AHEAD OF THE MID LEVEL TROUGH...SHRA/TSRA THAT DEVELOP
OVER MN WILL SPREAD TOWARD AND INTO THE CWA...MAINLY AFT 06Z. WITH
THE INITIAL PUSH OF 850-700 MB THETA-E ADVECTION SOME ISOLD SHRA/TSRA
MAY ALSO SPREAD INTO N CNTRL UPPER MI DURING THE EVENING...BUT
CONFIDENCE INTO CNTRL UPPER MI IS LOW WITH ONLY SLIGHT CHANCE POPS
MENTIONED. THE BEST CHANCE FOR SVR STORMS IS EXPECTED TO REMAIN WEST
OF THE CWA...CLOSER TO THE GREATER INSTABILITY. HOWEVER...WITH
MUCAPE VALUES TO AT LEAST 1K J/KG AND FAVORABLE 0-1KM/0-6KM SHEAR
TO 30/40 KNOTS...SOME STRONG STORMS WILL BE POSSIBLE WITH GUSTY
WINDS AND SMALL HAIL. THE MAIN HAZARD WITH TSRA LATE TONIGHT WILL BE
LOCALLY HEAVY RAIN WITH SOME ISOLD 1-2 INCH AMOUNTS POSSIBLE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 433 AM EDT SUN AUG 31 2014
UPPER LEVELS FEATURE TROUGHING OVER THE CENTRAL CONUS TO BEGIN THE
PERIOD BUT THAT GIVES WAY TO SHALLOW RIDGING BY MID WEEK. SHORTWAVE
TROUGH MOVES FROM ROCKIES TO CENTRAL CANADA BY LATE THIS WEEK...WITH
WARM SW FLOW ALOFT STREAMING ACROSS THE GREAT LAKES. COLD FRONT MOVES
THROUGH AROUND FRIDAY WITH SFC RIDGE AND DRY/COOLER AIR SETTLING
OVER UPPER GREAT LAKES BY NEXT WEEKEND. CHANCES FOR SHRA/TSRA ON
LABOR DAY AS STRONG SHORTWAVE AND COLD FRONT CROSS UPPER GREAT
LAKES. THERE WILL BE ADDITIONAL CHANCES FOR SHRA AND TSRA AHEAD AND
ALONG THE LATE WEEK COLD FRONT AS WELL. EXPECT TEMPS FOR THE MOST
PART TO BE ABOVE NORMAL THROUGH THE WEEK. TEMPS PROBABLY WILL NOT
FALL BLO NORMAL UNTIL NEXT WEEKEND IN WAKE OF THE COLD FRONT PASSAGE
ON FRIDAY.
THUNDER CHANCES AND STRENGTH ON LABOR DAY AND AGAIN WEDNESDAY NIGHT
THROUGH FRIDAY LOOKS TO BE THE HIGHEST IMPACT WEATHER THIS WEEK.
LABOR DAY...INITIAL SHORTWAVE CURRENTLY DRIVING SHRA/TSRA OVER THE
DAKOTAS LIFTS OVER ONTARIO TO START THE DAY WHILE ANOTHER SHORTWAVE
CURRENTLY OVER OREGON/IDAHO TRACKS TOWARD WESTERN GREAT LAKES. MAIN
SFC LOW WILL BE NORTH OF LK SUPERIOR CLOSER TO LEADING SHORTWAVE. SFC
TROUGH WILL EXTEND SOUTH ACROSS UPPER GREAT LAKES REGION AND ON INTO
THE SOUTHERN PLAINS. H85-H5 Q-VECTOR CONVERGENCE MOSTLY IMPACTS CWA
IN THE MORNING. MOISTURE TRANSPORT AT H85-H7 IS MAXIMIZED AHEAD OF
THE FRONT IN THE MORNING AS WELL. THERE WILL BE SOME RISK FOR
STRONGER STORMS AS DURING THIS PERIOD OF FORCING/LIFT THERE IS A H85
JET UP TO 50 KTS FM THE SOUTHWEST/0-6KM SHEAR OVER 40 KTS AND 1-6KM
MUCAPES UP TO 500 J/KG. FREEZING LEVEL IS BTWN 12-13KFT WITH STORM
CORES HAVING TO REACH ABOVE 35 KFT FOR POTENTIAL OF ONE-INCH HAIL.
INSTABILITY WILL BE LIMITING FACTOR...BUT THERE MAY BE AT LEAST
ISOLATED STRONGER STORMS. BY AFTN...MLCAPES SPIKE UP WELL OVER 1000
J/KG ESPECIALLY CNTRL CWA...BUT SFC FRONT IS ON ITS WAY ACROSS CWA BY
THAT TIME AND LARGER SCALE SUBSIDENCE SHOULD BE DEVELOPING IN WAKE OF
SHORTWAVES MOVING THROUGH LATE TONIGHT INTO MONDAY MORNING. IF SFC
FRONT SLOWS UP...EVEN JUST SLIGHTLY...ISOLD STORMS MAY TRY TO DEVELOP
WITH THE INCREASING DAYTIME HEATING/INSTABILITY. RISK OF SEVERE STILL
THERE AS WELL WITH 0-6KM SHEAR 35-40 KTS. MAX TEMPS ON LABOR DAY
HIGHLY DEPEND ON EXTENT OF CLOUD COVER...BUT SEEMS THAT MANY AREAS
WILL SEE READINGS WELL INTO THE 70S. SOUTH WINDS MAY BE GUSTY OVER
EASTERN THIRD OF CWA...ESPECIALLY NEAR LK MICHIGAN SHORE.
FRONT CLEARS EASTERN CWA BY MONDAY EVENING WITH HIGH PRESSURE
SETTLING ACROSS FOR LATER MONDAY NIGHT INTO TUESDAY. ONSHORE WNW
WINDS WILL KEEP LK SUPERIOR SHORE COOLER ON TUESDAY IN THE MID-UPR
60S...BUT TEMPS SHOULD MAINLY BE IN THE LOWER 70S ELSEWHERE.
AS FLOW ALOFT BECOMES MORE ZONAL BY WEDNESDAY MAY START TO SEE
WEAKER SHORTWAVES WORK ACROSS UPR LAKES. GFS/GEM-NH AGGRESSIVE
WITH QPF ON WEDNESDAY BUT GFS SOUNDINGS INDICATE DEEPER MOISTURE IS
LACKING WITH ONLY WEAKER SHORTWAVES SHOWN. PREFER SLOWER ECMWF
SOLUTION SHOWING BETTER CHANCES OF SHRA/TSRA ARRIVING BY WEDNESDAY
NIGHT AS STRONGER SHORTWAVE ARRIVES. LAST FEW RUNS OF ECMWF ARE
SHOWING GREATER SIGNAL OF THIS OCCURRING. STRONG LOW-LEVEL MOISTURE
TRANSPORT AIMED INTO THE UPR LAKES ALONG WITH LARGE AREA OF ML
MUCAPES OVER 1000-1500 J/KG UPSTREAM WITH LIFT ENHANCED BY RIGHT
ENTRANCE REGION OF JET STREAK OVER ONTARIO/QUEBEC COULD RESULT IN AT
LEAST ISOLD STRONG ELEVATED STORMS WEDNESDAY NIGHT INTO THURSDAY
MORNING WITH ANOTHER ROUND OF STRONGER SFC BASED STORMS ALONG FRONTAL
BOUNDARY POSSIBLE LATER THURSDAY. LIMITING FACTOR FOR ADDITIONAL
STORMS LATER IN THE DAY WOULD BE NOT AS MUCH MOISTURE ALONG THE SFC
FRONT IN WAKE OF THE SHORTWAVE THAT MOVES THROUGH THURSDAY MORNING.
TEMPS AHEAD OF THE FRONT ON THURSDAY COULD GET QUITE WARM AS H85
TEMPS SURGE TOWARD +20C. WITH FULL SUNSHINE THIS WOULD SUPPORT HIGHS
INTO THE UPPER 80S IF NOT LOWER 90S. CURRENT FORECAST IS MORE TOWARD
CONSENSUS WITH UNCERTAINTY ON CLOUDS AND PRECIP CHANCES. WILL BE
SOMETHING THAT MAY NEED ADJUSTING IN LATER FORECASTS THOUGH.
THE FRONT...ALONG WITH SOME POTENTIAL FOR ADDITIONAL SHRA/TSRA...
SLIDES EAST AND SOUTH OF MOST CWA BY FRIDAY. HIGH PRESSURE MOVES
ACROSS FOR AT LEAST THE START OF NEXT WEEKEND WITH A MODEST COOLING
TREND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 126 AM EDT SUN AUG 31 2014
EXPECT LINGERING VFR SC CIGS AT IWD AND CMX TO DISSIPATE AS HI PRES
BLDS OVER WRN UPR MI UNDER SUBSIDENCE IN THE WAKE OF DEPARTING UPR
DISTURBANCE. WITH LGT WINDS UNDER THE BLDG HI...EXPECT RADIATION FOG
TO DVLP AND DROP CONDITIONS TO LIFR AND EVEN VLIFR IN THE PRESENCE
OF NOCTURNAL COOLING/LINGERING HI SFC DEWPTS. A MORE STEADY...
UPSLOPE N WIND OFF LK SUP WL MAINTAIN IFR CONDITIONS AT SAW. THE
PRESENCE OF THESE CLDS WL LIMIT THE POTENTIAL FOR THICKER RADIATION
FOG AT SAW. WITH DAYTIME HEATING...EXPECT LINGERING FOG/LO CLDS TO
MIX OUT AND GIVE WAY TO VFR CONDITIONS. THIS PROCESS WL BE SLOWEST
AT SAW AS AN UPSLOPE NE VEERING SE WIND DVLPS ON THE WRN FLANK OF
SFC HI SHIFTING TO THE E. A STRENGTHENING SSW WIND WL OVERSPREAD THE
UPR LKS THIS EVNG BTWN THE DEPARTING SFC HI AND AN APRCHG COLD FNT.
WITH NOCTURNAL COOLING...A LLJ WL DVLP AND MAY BE SUFFICIENTLY
STRONG TO BRING MARGINAL LLWS TO AT LEAST THE WRN IWD/CMX TAF SITES.
RIGHT NOW...IT APPEARS THE INCOMING AIRMASS WL BE TOO DRY TO CAUSE
ANY LO CLDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 514 AM EDT SUN AUG 31 2014
WINDS WILL BE LESS THAN 20 KTS OR LESS THROUGH MOST OF THE PERIOD
EXCEPT FOR A PERIOD OF SE TO S GUSTS OF 20 TO 30 KNOTS TONIGHT AND
MONDAY MORNING. WINDS WILL THEN VEER WRLY TO 20 KNOTS MON AFTERNOON
AND MON NIGHT IN THE WAKE OF A LOW PRESSURE SYSTEM AND COLD FRONT.
WIDESPREAD FOG WILL CONTINUE THROUGH THIS MORNING AND THEN DEVELOP
AGAIN TONIGHT INTO MONDAY NIGHT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1207 PM CDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 245 AM CDT SUN AUG 31 2014
ALTHOUGH SUNDAY AND ITS POTENTIAL SEVERE WEATHER EVENT ARE
HERE...THE CAMS STILL LEAVE PLENTY OF QUESTIONS AS TO HOW THINGS
WILL EVOLVE LATER TODAY.
FOR THIS MORNING...INITIAL SURGE OF THE LLJ IS MOVING ACROSS THE
DAKOTAS OUT AHEAD OF SHORTWAVE THAT CAN BE SEEN ON WATER VAPOR
MOVING INTO CENTRAL SODAK. ALTHOUGH BEST FORCING AND MOST WIDESPREAD
THUNDERSTORM ACTIVITY CAN BE FOUND AT THE NOSE OF THE LLJ ACROSS
NODAK AND ON ITS WAY TO NW MN...ENOUGH THETA-E ADVECTION AND
ISENTROPIC LIFT IS PRESENT ON THE ERN FLANK OF THE LLJ TO GET SCT
CONVECTION DOWN INTO NE NEB. THE HRRR/HOPWRF/MPXWRF/NMM/ARW ALL SHOW
THIS BAND OF ISO/SCT SHOWERS WORKING ACROSS MN THROUGH THE
MORNING...SO WORKED SOME 20/30 POPS ACROSS MN THIS MORNING TO
ACCOUNT FOR THAT. EXPECT THIS ACTIVITY TO START WEAKENING AS IT
MOVES EAST ACROSS MN AND LIKELY WILL NOT MAKE IT INTO WI AS IT
ENCOUNTERS A PROGRESSIVELY DRIER AIRMASS /SEE 00Z SOUNDING FROM MPX
LAST NIGHT/.
IN THE WAKE OF THIS MORNING ACTIVITY...H85 TEMPS WILL BE INCREASING
TO AROUND 20C. LOOKING AT BUFKIT SOUNDINGS FROM ACROSS THE
AREA...THIS WILL PUT A DECENT CAP IN PLACE THAT LOOKS TO KEEP A LID
ON SURFACE BASED CONVECTION UNTIL ABOUT 00Z. WHERE WE ARE SEEING
SOME VARIABILITY THOUGH WITH THE CAMS IS WITH THE POTENTIAL FOR SOME
ELEVATED CONVECTION TO DEVELOP THIS AFTERNOON OUT AHEAD OF WHAT YOU
COULD CONSIDER THE MAIN SHOW FROM THE SEVERE WEATHER PERSPECTIVE.
THIS ELEVATED CONVECTION LOOKS TO BE TIED TO THE STRONG WAVE ON
WATER VAPOR CURRENTLY MOVING INTO WRN KS. THIS FEATURE HAS A FEW
STORMS ASSOCIATED WITH IT IN KANSAS THIS MORNING AND BY THE
AFTERNOON...THIS WAVE WILL BE NEAR THE MN/IA BORDER. THE CAMS THAT
ARE MOST BULLISH WITH THIS ACTIVITY ARE THE MPXWRF AND ARW...AND
ALTHOUGH IT ENDS AT 21Z...YOU GET A SENSE FROM THE HRRR REFLECTIVITY
FORECAST...IT MAY BE GOING THE SAME WAY IN THE NEXT COUPLE OF RUNS.
THE IMPACT OF THIS ACTIVITY ON THE FORECAST WAS TO SPREAD HIGHER
POPS A BIT FARTHER EAST LATE THIS AFTERNOON THAN THE POSITION OF THE
SFC FEATURES WOULD OTHERWISE SUGGEST.
AS FOR THE POTENTIAL SFC BASED CONVECTION...THE MAIN TREND SEEN WITH
THE CAMS AND 00Z DETERMINISTIC MODELS WAS DELAY ITS START
SOME...WHICH MAKE SENSE GIVEN THE CAPPING SEEN IN THE FORECAST
SOUNDINGS. CURRENT EXPECTATIONS ARE THAT SFC BASED CONVECTION WILL
DEVELOP AROUND 21Z NEAR OMAHA...WHERE INSTABILITY WILL BE
MAXIMIZED...WITH INITIATION ALONG THE FRONT UP IN MN COMING A BIT
CLOSER TO 00Z. GREATEST SEVERE THREAT REALLY LOOKS TO BE DOWN ACROSS
IOWA...WHERE THE COMBINATION OF AN IMPINGING WRLY MID LEVEL JET WITH
A 40-50 KT SWRLY LLJ LOOKS TO MAXIMIZE SHEAR. CAN NOT ARGUE WITH THE
DAY1 SEVERE PROBABILITIES...WHICH HAS THE GREATER SEVERE POTENTIAL
EXISTING FROM I-90 SOUTH. LOOKING AT THE 0-3/0-6 KM SHEAR OF 30-60
KTS WITH VECTORS ORIENTED MOSTLY PERPENDICULAR TO THE FRONT ACROSS
IOWA INDICATES THE POTENTIAL FOR GETTING A STRONG MCS WITH STRONG
WINDS ACROSS IOWA TONIGHT...WHICH IS WHAT THE NMM/ARW CERTAINLY SHOW
EVOLVING. STILL A GOOD DEGREE OF VARIABILITY WITH HOW THIS ACTIVITY
WILL EVOLVE ACROSS THE MPX CWA...WITH SOME SUGGESTION THAT WE MAY
SEE THE GREATEST THUNDERSTORM ACTIVITY SPLIT THE MPX CWA TO THE
NORTH AND SOUTH. CERTAINLY THE HRRR MSLP FORECAST SHOWS SOME MERIT
TO THIS POSSIBILITY...WITH TWO SFC LOWS NOTED BY 21Z. ONE UP IN NRN
MN AND THE OTHER IN WRN KS.
FOR TONIGHT...WE ARE ALSO SEEING THE NMM AND THE ARW TO A LESSER
EXTENT HANGING UP ACTIVITY BACK ACROSS THE CENTER OF THE MPX CWA AS
THEY BOTH DEVELOP A DEFORMATION BAND IN THE WAKE IN THE MAIN COLD
FRONT ACTIVITY. THIS LOOKS TO BE TIED TO THE MAIN SHORT WAVE
POSSIBLY MIXED WITH A BIT OF AN MCV MOVING ACROSS THE UPPER MS
VALLEY LATE TONIGHT. AS A RESULT...HELD ON TO CHANCE POPS A BIT
LONGER BACK ACROSS MOST OF THE MN PORTION OF THE MPX CWA IN THE WAKE
OF THE FRONT. THIS ACTIVITY WOULD NOT HAVE MUCH OF A SEVERE
THREAT...THOUGH IT WOULD SET UP MORE IN A WAY TO ALLOW FOR SOME
TRAINING OF STORMS ALONG A SW TO NE AXIS...SO IT COULD POSE MORE OF
A HYDRO THREAT IF IT MATERIALIZES.
TO SUMMARIZE...WE EXPECT A BAND OF NON-SEVERE SHOWERS/STORMS TO MOVE
ACROSS MN THIS MORNING. STILL A GOOD DEGREE OF UNCERTAINTY WITH
RESPECT THE AFTERNOON ACTIVITY...WITH THE POTENTIAL FOR A PREFRONTAL
TROUGH TO GET ELEVATED CONVECTION GOING BY EARLY AFTERNOON IN THE
EAST...WITH THE GREATEST SEVERE RISK EXISTING FROM ABOUT 6 PM TO
MIDNIGHT FROM SOUTH CENTRAL MN INTO IOWA AHEAD OF THE MAIN SFC COLD
FRONT. EVENTUALLY...A LINE OR TWO OF STORMS LOOKS TO FORM...WITH THE
MAIN SEVERE THREAT BEING DAMAGING STRAIGHT LINE WINDS.
HOWEVER...WHERE ACTIVITY INITIALLY DEVELOPS...IT WILL LIKELY BE
SUPER CELLULAR IN NATURE...WITH LARGE HAIL AND A FEW TORNADOES BEING
POSSIBLE AS WELL...BUT THIS THREAT LOOKS GREATEST FROM ERN NEB INTO
WRN IOWA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 245 AM CDT SUN AUG 31 2014
THE LONGER TERM WILL INCLUDE SOME ADDITIONAL CHANCES FOR
SHRA/TSRA AS WE SEE THE LARGE SCALE PATTERN ONCE AGAIN BECOME MORE
ZONAL BY THE MIDDLE OF THE WEEK... BEFORE ANOTHER UPPER TROUGH
MOVES INTO THE CENTER OF THE COUNTRY TOWARD THE WEEKEND. THE
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH
MIDWEEK... BUT DIVERGES A FAIR AMOUNT BY THE WEEKEND... WHICH
LEADS TO MORE UNCERTAINTY AND NECESSITATES THE INCLUSION OF CHANCE
POPS FOR SEVERAL DAYS.
SOME PCPN WILL LIKELY STILL BE ONGOING ACROSS THE EASTERN PORTION
OF THE AREA ON MONDAY AS THE FRONTAL BOUNDARY SLOWLY PUSHES EAST
INTO THE GREAT LAKES. COULD SEE A FEW SHRA/TSRA SNEAK BACK INTO
THE WESTERN AND CENTRAL PORTION OF THE AREA MONDAY NIGHT INTO
EARLY TUESDAY AS THE UPPER TROUGH/COLD POOL SWING THROUGH THE
REGION. THIS ACTIVITY WILL SHIFT NORTHEAST BY TUESDAY... WITH
RETURN FLOW BEGINNING TO SETUP BY TUESDAY NIGHT. CHANCES FOR
SHRA/TSRA LOOK TO RETURN FROM WEST TO EAST WEDNESDAY INTO THURSDAY
AS A SURFACE LOW SLOWLY TAKES SHAPE OVER THE PLAINS AHEAD OF THE
NEXT UPPER TROUGH... WITH A LONG PERIOD OF MAINLY WEAK ISENTROPIC
LIFT PROGGED ACROSS OUR AREA. THE SPEED WITH WHICH THE SURFACE LOW
MOVES THROUGH OUR AREA VARIES QUITE A BIT AMONGST THE GUIDANCE...
AND AT THIS POINT THERE IS TOO MUCH SPREAD IN THE ENSEMBLE
SOLUTIONS TO HAVE MUCH CONFIDENCE IN ANYTHING SPECIFIC. UNTIL THE
SURFACE LOW AND ASSOCIATED FRONTAL BOUNDARY MOVE THROUGH... WE/LL
CONTINUE TO HAVE A NEED FOR AT LEAST CHANCE POPS. THERE IS ALSO
UNCERTAINTY IN HOW FAR SOUTH THE BOUNDARY WILL BE DISPLACED ONCE
THE SURFACE LOW AND UPPER TROUGH MOVE EAST... WITH THE GUIDANCE
SHOWING VARYING AMPLITUDES OF THE UPPER TROUGH WHICH LEADS TO
DIFFERENCES IN HOW FAR SOUTH THE BOUNDARY IS DISPLACED AS THE
SURFACE HIGH BUILDS INTO THE AREA LATE FRIDAY INTO SATURDAY. AT
THIS POINT... KEPT SOME POPS OVER THE SOUTHERN PART OF THE AREA
INTO SATURDAY TO ACCOUNT FOR THE POSSIBILITY OF THE BOUNDARY
HANGING UP OVER NORTHERN IOWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1155 AM CDT SUN AUG 31 2014
LOW CONFIDENCE IN TSRA/SHRA DEVELOPMENT AFT 21Z WITH SHORT TERM
MODELS HAVING PROBLEMS WITH THE CONVECTION ALREADY DEVELOPING NEAR
KRWF/KFRM AS OF 17Z. WILL USE REGIONAL RADAR AND MOVEMENT TRENDS
FOR THE FIRST 3 HRS AS THIS LINE BECOMES MORE ORGANIZED AND MOVES
OFF TO THE NE. KRWF/KSTC WILL BE MOST IMPACTED IN THE SHORT TERM.
ELSEWHERE...TSRA/SHRA SHOULD HOLD OFF UNTIL AFT 21Z...WITH A
BETTER CHC AFT 00Z AS THE MAIN UPPER WAVE AND SFC FRONT MOVES
CLOSER TO THE AREA. WINDS WILL BE GUSTY THIS AFTN FROM THE
S/SW...WITH A MORE SW/WSW BY THE LATE AFTN IN WC/SW MN AND
DECREASE TO LESS THAN 10 KTS. EC MN/WC WI WILL LIKELY SEE THE
GUSTY WINDS UNTIL 00Z FROM THE S/SSW.
AM CONCERN WITH AREAS FROM SC/EC MN...EASTWARD ACROSS WC WI AFT 2Z
AS A LARGE AREA OF CONVECTION IS EXPECTED TO DEVELOP. WILL ADJUST
AS NECESSARY BUT IFR/MVFR CIGS/VSBYS FOR KRNH/KEAU LOOK MORE
LIKELY OVERNIGHT.
KMSP...
BASED ON THE LATEST REGIONAL RADAR MOST OF THE ACTIVITY SHOULD
HOLD OFF TO THE WEST UNTIL AFT 20-21Z...WITH A PERIOD OF VCTS FROM
20-23Z...BUT LOW CONFIDENCE ON AREAL EXTENT. A BETTER CHC OF
WIDESPREAD ACTIVITY IS EXPECTED AFT 2Z...WITH A PERIOD OF HEAVY
SHRA/TSRA AND LOW VSBYS. AFT 6Z...CHC/S OF SHRA/TSRA
DIMINISH...BUT MVFR CIGS AND/OR VSBYS MAY DEVELOP BEHIND THE SFC
FRONT...ESPECIALLY DURING THE TYPICAL 09-14Z TIME FRAME. IF MVFR
CIGS DEVELOP...DO NOT EXPECT VFR CONDS UNTIL AFT 16-18Z ON MONDAY.
/OUTLOOK FOR KMSP/
MON...VFR BY AFTERNOON WINDS WNW 5-10 KTS.
TUE...VFR. WINDS WSW 5-10 KTS.
WED...VFR. CHC MVFR/TSRA LATE. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
609 AM CDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 245 AM CDT SUN AUG 31 2014
ALTHOUGH SUNDAY AND ITS POTENTIAL SEVERE WEATHER EVENT ARE
HERE...THE CAMS STILL LEAVE PLENTY OF QUESTIONS AS TO HOW THINGS
WILL EVOLVE LATER TODAY.
FOR THIS MORNING...INITIAL SURGE OF THE LLJ IS MOVING ACROSS THE
DAKOTAS OUT AHEAD OF SHORTWAVE THAT CAN BE SEEN ON WATER VAPOR
MOVING INTO CENTRAL SODAK. ALTHOUGH BEST FORCING AND MOST WIDESPREAD
THUNDERSTORM ACTIVITY CAN BE FOUND AT THE NOSE OF THE LLJ ACROSS
NODAK AND ON ITS WAY TO NW MN...ENOUGH THETA-E ADVECTION AND
ISENTROPIC LIFT IS PRESENT ON THE ERN FLANK OF THE LLJ TO GET SCT
CONVECTION DOWN INTO NE NEB. THE HRRR/HOPWRF/MPXWRF/NMM/ARW ALL SHOW
THIS BAND OF ISO/SCT SHOWERS WORKING ACROSS MN THROUGH THE
MORNING...SO WORKED SOME 20/30 POPS ACROSS MN THIS MORNING TO
ACCOUNT FOR THAT. EXPECT THIS ACTIVITY TO START WEAKENING AS IT
MOVES EAST ACROSS MN AND LIKELY WILL NOT MAKE IT INTO WI AS IT
ENCOUNTERS A PROGRESSIVELY DRIER AIRMASS /SEE 00Z SOUNDING FROM MPX
LAST NIGHT/.
IN THE WAKE OF THIS MORNING ACTIVITY...H85 TEMPS WILL BE INCREASING
TO AROUND 20C. LOOKING AT BUFKIT SOUNDINGS FROM ACROSS THE
AREA...THIS WILL PUT A DECENT CAP IN PLACE THAT LOOKS TO KEEP A LID
ON SURFACE BASED CONVECTION UNTIL ABOUT 00Z. WHERE WE ARE SEEING
SOME VARIABILITY THOUGH WITH THE CAMS IS WITH THE POTENTIAL FOR SOME
ELEVATED CONVECTION TO DEVELOP THIS AFTERNOON OUT AHEAD OF WHAT YOU
COULD CONSIDER THE MAIN SHOW FROM THE SEVERE WEATHER PERSPECTIVE.
THIS ELEVATED CONVECTION LOOKS TO BE TIED TO THE STRONG WAVE ON
WATER VAPOR CURRENTLY MOVING INTO WRN KS. THIS FEATURE HAS A FEW
STORMS ASSOCIATED WITH IT IN KANSAS THIS MORNING AND BY THE
AFTERNOON...THIS WAVE WILL BE NEAR THE MN/IA BORDER. THE CAMS THAT
ARE MOST BULLISH WITH THIS ACTIVITY ARE THE MPXWRF AND ARW...AND
ALTHOUGH IT ENDS AT 21Z...YOU GET A SENSE FROM THE HRRR REFLECTIVITY
FORECAST...IT MAY BE GOING THE SAME WAY IN THE NEXT COUPLE OF RUNS.
THE IMPACT OF THIS ACTIVITY ON THE FORECAST WAS TO SPREAD HIGHER
POPS A BIT FARTHER EAST LATE THIS AFTERNOON THAN THE POSITION OF THE
SFC FEATURES WOULD OTHERWISE SUGGEST.
AS FOR THE POTENTIAL SFC BASED CONVECTION...THE MAIN TREND SEEN WITH
THE CAMS AND 00Z DETERMINISTIC MODELS WAS DELAY ITS START
SOME...WHICH MAKE SENSE GIVEN THE CAPPING SEEN IN THE FORECAST
SOUNDINGS. CURRENT EXPECTATIONS ARE THAT SFC BASED CONVECTION WILL
DEVELOP AROUND 21Z NEAR OMAHA...WHERE INSTABILITY WILL BE
MAXIMIZED...WITH INITIATION ALONG THE FRONT UP IN MN COMING A BIT
CLOSER TO 00Z. GREATEST SEVERE THREAT REALLY LOOKS TO BE DOWN ACROSS
IOWA...WHERE THE COMBINATION OF AN IMPINGING WRLY MID LEVEL JET WITH
A 40-50 KT SWRLY LLJ LOOKS TO MAXIMIZE SHEAR. CAN NOT ARGUE WITH THE
DAY1 SEVERE PROBABILITIES...WHICH HAS THE GREATER SEVERE POTENTIAL
EXISTING FROM I-90 SOUTH. LOOKING AT THE 0-3/0-6 KM SHEAR OF 30-60
KTS WITH VECTORS ORIENTED MOSTLY PERPENDICULAR TO THE FRONT ACROSS
IOWA INDICATES THE POTENTIAL FOR GETTING A STRONG MCS WITH STRONG
WINDS ACROSS IOWA TONIGHT...WHICH IS WHAT THE NMM/ARW CERTAINLY SHOW
EVOLVING. STILL A GOOD DEGREE OF VARIABILITY WITH HOW THIS ACTIVITY
WILL EVOLVE ACROSS THE MPX CWA...WITH SOME SUGGESTION THAT WE MAY
SEE THE GREATEST THUNDERSTORM ACTIVITY SPLIT THE MPX CWA TO THE
NORTH AND SOUTH. CERTAINLY THE HRRR MSLP FORECAST SHOWS SOME MERIT
TO THIS POSSIBILITY...WITH TWO SFC LOWS NOTED BY 21Z. ONE UP IN NRN
MN AND THE OTHER IN WRN KS.
FOR TONIGHT...WE ARE ALSO SEEING THE NMM AND THE ARW TO A LESSER
EXTENT HANGING UP ACTIVITY BACK ACROSS THE CENTER OF THE MPX CWA AS
THEY BOTH DEVELOP A DEFORMATION BAND IN THE WAKE IN THE MAIN COLD
FRONT ACTIVITY. THIS LOOKS TO BE TIED TO THE MAIN SHORT WAVE
POSSIBLY MIXED WITH A BIT OF AN MCV MOVING ACROSS THE UPPER MS
VALLEY LATE TONIGHT. AS A RESULT...HELD ON TO CHANCE POPS A BIT
LONGER BACK ACROSS MOST OF THE MN PORTION OF THE MPX CWA IN THE WAKE
OF THE FRONT. THIS ACTIVITY WOULD NOT HAVE MUCH OF A SEVERE
THREAT...THOUGH IT WOULD SET UP MORE IN A WAY TO ALLOW FOR SOME
TRAINING OF STORMS ALONG A SW TO NE AXIS...SO IT COULD POSE MORE OF
A HYDRO THREAT IF IT MATERIALIZES.
TO SUMMARIZE...WE EXPECT A BAND OF NON-SEVERE SHOWERS/STORMS TO MOVE
ACROSS MN THIS MORNING. STILL A GOOD DEGREE OF UNCERTAINTY WITH
RESPECT THE AFTERNOON ACTIVITY...WITH THE POTENTIAL FOR A PREFRONTAL
TROUGH TO GET ELEVATED CONVECTION GOING BY EARLY AFTERNOON IN THE
EAST...WITH THE GREATEST SEVERE RISK EXISTING FROM ABOUT 6 PM TO
MIDNIGHT FROM SOUTH CENTRAL MN INTO IOWA AHEAD OF THE MAIN SFC COLD
FRONT. EVENTUALLY...A LINE OR TWO OF STORMS LOOKS TO FORM...WITH THE
MAIN SEVERE THREAT BEING DAMAGING STRAIGHT LINE WINDS.
HOWEVER...WHERE ACTIVITY INITIALLY DEVELOPS...IT WILL LIKELY BE
SUPER CELLULAR IN NATURE...WITH LARGE HAIL AND A FEW TORNADOES BEING
POSSIBLE AS WELL...BUT THIS THREAT LOOKS GREATEST FROM ERN NEB INTO
WRN IOWA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 245 AM CDT SUN AUG 31 2014
THE LONGER TERM WILL INCLUDE SOME ADDITIONAL CHANCES FOR
SHRA/TSRA AS WE SEE THE LARGE SCALE PATTERN ONCE AGAIN BECOME MORE
ZONAL BY THE MIDDLE OF THE WEEK... BEFORE ANOTHER UPPER TROUGH
MOVES INTO THE CENTER OF THE COUNTRY TOWARD THE WEEKEND. THE
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH
MIDWEEK... BUT DIVERGES A FAIR AMOUNT BY THE WEEKEND... WHICH
LEADS TO MORE UNCERTAINTY AND NECESSITATES THE INCLUSION OF CHANCE
POPS FOR SEVERAL DAYS.
SOME PCPN WILL LIKELY STILL BE ONGOING ACROSS THE EASTERN PORTION
OF THE AREA ON MONDAY AS THE FRONTAL BOUNDARY SLOWLY PUSHES EAST
INTO THE GREAT LAKES. COULD SEE A FEW SHRA/TSRA SNEAK BACK INTO
THE WESTERN AND CENTRAL PORTION OF THE AREA MONDAY NIGHT INTO
EARLY TUESDAY AS THE UPPER TROUGH/COLD POOL SWING THROUGH THE
REGION. THIS ACTIVITY WILL SHIFT NORTHEAST BY TUESDAY... WITH
RETURN FLOW BEGINNING TO SETUP BY TUESDAY NIGHT. CHANCES FOR
SHRA/TSRA LOOK TO RETURN FROM WEST TO EAST WEDNESDAY INTO THURSDAY
AS A SURFACE LOW SLOWLY TAKES SHAPE OVER THE PLAINS AHEAD OF THE
NEXT UPPER TROUGH... WITH A LONG PERIOD OF MAINLY WEAK ISENTROPIC
LIFT PROGGED ACROSS OUR AREA. THE SPEED WITH WHICH THE SURFACE LOW
MOVES THROUGH OUR AREA VARIES QUITE A BIT AMONGST THE GUIDANCE...
AND AT THIS POINT THERE IS TOO MUCH SPREAD IN THE ENSEMBLE
SOLUTIONS TO HAVE MUCH CONFIDENCE IN ANYTHING SPECIFIC. UNTIL THE
SURFACE LOW AND ASSOCIATED FRONTAL BOUNDARY MOVE THROUGH... WE/LL
CONTINUE TO HAVE A NEED FOR AT LEAST CHANCE POPS. THERE IS ALSO
UNCERTAINTY IN HOW FAR SOUTH THE BOUNDARY WILL BE DISPLACED ONCE
THE SURFACE LOW AND UPPER TROUGH MOVE EAST... WITH THE GUIDANCE
SHOWING VARYING AMPLITUDES OF THE UPPER TROUGH WHICH LEADS TO
DIFFERENCES IN HOW FAR SOUTH THE BOUNDARY IS DISPLACED AS THE
SURFACE HIGH BUILDS INTO THE AREA LATE FRIDAY INTO SATURDAY. AT
THIS POINT... KEPT SOME POPS OVER THE SOUTHERN PART OF THE AREA
INTO SATURDAY TO ACCOUNT FOR THE POSSIBILITY OF THE BOUNDARY
HANGING UP OVER NORTHERN IOWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 558 AM CDT SUN AUG 31 2014
EXTENSIVE FOG/LOW STRATUS THAT DEVELOPED OVER WI BENEATH THE SFC
HIGH HAS MANAGED TO WORK INTO ERN MN/WRN WI ON SOUTHEAST WINDS
THIS MORNING. AS WINDS CONTINUE TO BECOME MORE SRLY AND PICK UP IN
STRENGTH...WE SHOULD SEE THESE CLOUDS MIX OUT PRETTY QUICK THIS
MORNING. SHOWERS THAT SNUCK INTO WRN MN EARLY THIS MORNING WILL
CONTINUE TO SLOWLY FALL APPART AS THEY WORK ACROSS MN AND FEEL
VCSH MENTIONS AT MN TERMINALS IS ENOUGH FOR THIS MORNING. FOR THE
AFTERNOON...BEGINNING TO FAVOR THE HRRR/ARW TREND FOR STORMS
TODAY...WITH STORMS DEVELOPING NEAR THE MN/WI BORDER AROUND 20Z ON
A LEAD TROUGH...WITH THE MAIN COLD FRONTAL ACTIVITY NOT LOOKING TO
REALLY GET GOING IN MN UNTIL AFTER 00Z. BEHIND THIS
ACTIVITY...GFSLAMP IS WANTING TO DEVELOP LOW STRATUS...BUT 925-850
RH FORECASTS FROM THE NAM/GFS INDICATE THE STRATUS BEING FAVORED
FOR NRN MN...SO KEPT CIGS VFR TONIGHT.
KMSP...CONFIDENCE IS NOT AT THE CERTAIN LEVEL FOR MSP GETTING
STORMS THIS AFTERNOON...AS SEVERAL OF THE CAMS ARE SHOWING
AFTERNOON ACTIVITY MAINLY IMPACTING WI...WHILE STRONGER STORMS
TONIGHT STAY OFF TO THE SOUTH. IT IS THIS SECONDARY ACTIVITY
THOUGH THAT LOOKS TO HAVE THE GREATEST POTENTIAL FOR IMPACTING THE
FIELD...WHICH IS WHY THE TEMPO GROUP IS STILL THERE FROM 1-4Z.
MOVED THE VCTS MENTION UP TO 21Z TO ACCOUNT FOR UNCERTAINTY FOR
WHERE STORMS WILL DEVELOP ALONG THE PREFRONTAL TROUGH THIS
AFTERNOON. GIVEN STRENGTH OF WINDS...SHOULD NOT TAKE TOO LONG TO
MIX OUT LOW STRATUS THIS MORNING...WITH THAT LOOKING TO OCCUR
BETWEEN 14Z AND 15Z.
/OUTLOOK FOR KMSP/
MON...MVFR/TSRA ENDING EARLY. VFR BY AFTERNOON WINDS WNW 5-10 KTS.
TUE...VFR. WINDS WSW 5-10 KTS.
WED...VFR. CHC MVFR/TSRA LATE. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
338 AM CDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 245 AM CDT SUN AUG 31 2014
ALTHOUGH SUNDAY AND ITS POTENTIAL SEVERE WEATHER EVENT ARE
HERE...THE CAMS STILL LEAVE PLENTY OF QUESTIONS AS TO HOW THINGS
WILL EVOLVE LATER TODAY.
FOR THIS MORNING...INITIAL SURGE OF THE LLJ IS MOVING ACROSS THE
DAKOTAS OUT AHEAD OF SHORTWAVE THAT CAN BE SEEN ON WATER VAPOR
MOVING INTO CENTRAL SODAK. ALTHOUGH BEST FORCING AND MOST WIDESPREAD
THUNDERSTORM ACTIVITY CAN BE FOUND AT THE NOSE OF THE LLJ ACROSS
NODAK AND ON ITS WAY TO NW MN...ENOUGH THETA-E ADVECTION AND
ISENTROPIC LIFT IS PRESENT ON THE ERN FLANK OF THE LLJ TO GET SCT
CONVECTION DOWN INTO NE NEB. THE HRRR/HOPWRF/MPXWRF/NMM/ARW ALL SHOW
THIS BAND OF ISO/SCT SHOWERS WORKING ACROSS MN THROUGH THE
MORNING...SO WORKED SOME 20/30 POPS ACROSS MN THIS MORNING TO
ACCOUNT FOR THAT. EXPECT THIS ACTIVITY TO START WEAKENING AS IT
MOVES EAST ACROSS MN AND LIKELY WILL NOT MAKE IT INTO WI AS IT
ENCOUNTERS A PROGRESSIVELY DRIER AIRMASS /SEE 00Z SOUNDING FROM MPX
LAST NIGHT/.
IN THE WAKE OF THIS MORNING ACTIVITY...H85 TEMPS WILL BE INCREASING
TO AROUND 20C. LOOKING AT BUFKIT SOUNDINGS FROM ACROSS THE
AREA...THIS WILL PUT A DECENT CAP IN PLACE THAT LOOKS TO KEEP A LID
ON SURFACE BASED CONVECTION UNTIL ABOUT 00Z. WHERE WE ARE SEEING
SOME VARIABILITY THOUGH WITH THE CAMS IS WITH THE POTENTIAL FOR SOME
ELEVATED CONVECTION TO DEVELOP THIS AFTERNOON OUT AHEAD OF WHAT YOU
COULD CONSIDER THE MAIN SHOW FROM THE SEVERE WEATHER PERSPECTIVE.
THIS ELEVATED CONVECTION LOOKS TO BE TIED TO THE STRONG WAVE ON
WATER VAPOR CURRENTLY MOVING INTO WRN KS. THIS FEATURE HAS A FEW
STORMS ASSOCIATED WITH IT IN KANSAS THIS MORNING AND BY THE
AFTERNOON...THIS WAVE WILL BE NEAR THE MN/IA BORDER. THE CAMS THAT
ARE MOST BULLISH WITH THIS ACTIVITY ARE THE MPXWRF AND ARW...AND
ALTHOUGH IT ENDS AT 21Z...YOU GET A SENSE FROM THE HRRR REFLECTIVITY
FORECAST...IT MAY BE GOING THE SAME WAY IN THE NEXT COUPLE OF RUNS.
THE IMPACT OF THIS ACTIVITY ON THE FORECAST WAS TO SPREAD HIGHER
POPS A BIT FARTHER EAST LATE THIS AFTERNOON THAN THE POSITION OF THE
SFC FEATURES WOULD OTHERWISE SUGGEST.
AS FOR THE POTENTIAL SFC BASED CONVECTION...THE MAIN TREND SEEN WITH
THE CAMS AND 00Z DETERMINISTIC MODELS WAS DELAY ITS START
SOME...WHICH MAKE SENSE GIVEN THE CAPPING SEEN IN THE FORECAST
SOUNDINGS. CURRENT EXPECTATIONS ARE THAT SFC BASED CONVECTION WILL
DEVELOP AROUND 21Z NEAR OMAHA...WHERE INSTABILITY WILL BE
MAXIMIZED...WITH INITIATION ALONG THE FRONT UP IN MN COMING A BIT
CLOSER TO 00Z. GREATEST SEVERE THREAT REALLY LOOKS TO BE DOWN ACROSS
IOWA...WHERE THE COMBINATION OF AN IMPINGING WRLY MID LEVEL JET WITH
A 40-50 KT SWRLY LLJ LOOKS TO MAXIMIZE SHEAR. CAN NOT ARGUE WITH THE
DAY1 SEVERE PROBABILITIES...WHICH HAS THE GREATER SEVERE POTENTIAL
EXISTING FROM I-90 SOUTH. LOOKING AT THE 0-3/0-6 KM SHEAR OF 30-60
KTS WITH VECTORS ORIENTED MOSTLY PERPENDICULAR TO THE FRONT ACROSS
IOWA INDICATES THE POTENTIAL FOR GETTING A STRONG MCS WITH STRONG
WINDS ACROSS IOWA TONIGHT...WHICH IS WHAT THE NMM/ARW CERTAINLY SHOW
EVOLVING. STILL A GOOD DEGREE OF VARIABILITY WITH HOW THIS ACTIVITY
WILL EVOLVE ACROSS THE MPX CWA...WITH SOME SUGGESTION THAT WE MAY
SEE THE GREATEST THUNDERSTORM ACTIVITY SPLIT THE MPX CWA TO THE
NORTH AND SOUTH. CERTAINLY THE HRRR MSLP FORECAST SHOWS SOME MERIT
TO THIS POSSIBILITY...WITH TWO SFC LOWS NOTED BY 21Z. ONE UP IN NRN
MN AND THE OTHER IN WRN KS.
FOR TONIGHT...WE ARE ALSO SEEING THE NMM AND THE ARW TO A LESSER
EXTENT HANGING UP ACTIVITY BACK ACROSS THE CENTER OF THE MPX CWA AS
THEY BOTH DEVELOP A DEFORMATION BAND IN THE WAKE IN THE MAIN COLD
FRONT ACTIVITY. THIS LOOKS TO BE TIED TO THE MAIN SHORT WAVE
POSSIBLY MIXED WITH A BIT OF AN MCV MOVING ACROSS THE UPPER MS
VALLEY LATE TONIGHT. AS A RESULT...HELD ON TO CHANCE POPS A BIT
LONGER BACK ACROSS MOST OF THE MN PORTION OF THE MPX CWA IN THE WAKE
OF THE FRONT. THIS ACTIVITY WOULD NOT HAVE MUCH OF A SEVERE
THREAT...THOUGH IT WOULD SET UP MORE IN A WAY TO ALLOW FOR SOME
TRAINING OF STORMS ALONG A SW TO NE AXIS...SO IT COULD POSE MORE OF
A HYDRO THREAT IF IT MATERIALIZES.
TO SUMMARIZE...WE EXPECT A BAND OF NON-SEVERE SHOWERS/STORMS TO MOVE
ACROSS MN THIS MORNING. STILL A GOOD DEGREE OF UNCERTAINTY WITH
RESPECT THE AFTERNOON ACTIVITY...WITH THE POTENTIAL FOR A PREFRONTAL
TROUGH TO GET ELEVATED CONVECTION GOING BY EARLY AFTERNOON IN THE
EAST...WITH THE GREATEST SEVERE RISK EXISTING FROM ABOUT 6 PM TO
MIDNIGHT FROM SOUTH CENTRAL MN INTO IOWA AHEAD OF THE MAIN SFC COLD
FRONT. EVENTUALLY...A LINE OR TWO OF STORMS LOOKS TO FORM...WITH THE
MAIN SEVERE THREAT BEING DAMAGING STRAIGHT LINE WINDS.
HOWEVER...WHERE ACTIVITY INITIALLY DEVELOPS...IT WILL LIKELY BE
SUPER CELLULAR IN NATURE...WITH LARGE HAIL AND A FEW TORNADOES BEING
POSSIBLE AS WELL...BUT THIS THREAT LOOKS GREATEST FROM ERN NEB INTO
WRN IOWA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 245 AM CDT SUN AUG 31 2014
THE LONGER TERM WILL INCLUDE SOME ADDITIONAL CHANCES FOR
SHRA/TSRA AS WE SEE THE LARGE SCALE PATTERN ONCE AGAIN BECOME MORE
ZONAL BY THE MIDDLE OF THE WEEK... BEFORE ANOTHER UPPER TROUGH
MOVES INTO THE CENTER OF THE COUNTRY TOWARD THE WEEKEND. THE
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH
MIDWEEK... BUT DIVERGES A FAIR AMOUNT BY THE WEEKEND... WHICH
LEADS TO MORE UNCERTAINTY AND NECESSITATES THE INCLUSION OF CHANCE
POPS FOR SEVERAL DAYS.
SOME PCPN WILL LIKELY STILL BE ONGOING ACROSS THE EASTERN PORTION
OF THE AREA ON MONDAY AS THE FRONTAL BOUNDARY SLOWLY PUSHES EAST
INTO THE GREAT LAKES. COULD SEE A FEW SHRA/TSRA SNEAK BACK INTO
THE WESTERN AND CENTRAL PORTION OF THE AREA MONDAY NIGHT INTO
EARLY TUESDAY AS THE UPPER TROUGH/COLD POOL SWING THROUGH THE
REGION. THIS ACTIVITY WILL SHIFT NORTHEAST BY TUESDAY... WITH
RETURN FLOW BEGINNING TO SETUP BY TUESDAY NIGHT. CHANCES FOR
SHRA/TSRA LOOK TO RETURN FROM WEST TO EAST WEDNESDAY INTO THURSDAY
AS A SURFACE LOW SLOWLY TAKES SHAPE OVER THE PLAINS AHEAD OF THE
NEXT UPPER TROUGH... WITH A LONG PERIOD OF MAINLY WEAK ISENTROPIC
LIFT PROGGED ACROSS OUR AREA. THE SPEED WITH WHICH THE SURFACE LOW
MOVES THROUGH OUR AREA VARIES QUITE A BIT AMONGST THE GUIDANCE...
AND AT THIS POINT THERE IS TOO MUCH SPREAD IN THE ENSEMBLE
SOLUTIONS TO HAVE MUCH CONFIDENCE IN ANYTHING SPECIFIC. UNTIL THE
SURFACE LOW AND ASSOCIATED FRONTAL BOUNDARY MOVE THROUGH... WE/LL
CONTINUE TO HAVE A NEED FOR AT LEAST CHANCE POPS. THERE IS ALSO
UNCERTAINTY IN HOW FAR SOUTH THE BOUNDARY WILL BE DISPLACED ONCE
THE SURFACE LOW AND UPPER TROUGH MOVE EAST... WITH THE GUIDANCE
SHOWING VARYING AMPLITUDES OF THE UPPER TROUGH WHICH LEADS TO
DIFFERENCES IN HOW FAR SOUTH THE BOUNDARY IS DISPLACED AS THE
SURFACE HIGH BUILDS INTO THE AREA LATE FRIDAY INTO SATURDAY. AT
THIS POINT... KEPT SOME POPS OVER THE SOUTHERN PART OF THE AREA
INTO SATURDAY TO ACCOUNT FOR THE POSSIBILITY OF THE BOUNDARY
HANGING UP OVER NORTHERN IOWA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1233 AM CDT SUN AUG 31 2014
WITH THE HRRR ALONG WITH VIRTUALLY ALL OTHER CAMS SHOWING A BAND
OF SHRA/TSRA WORKING ACROSS MN WITH INITIAL ARRIVAL OF THE
LLJ...STARTED TO INTRODUCE VCSH IN THE MORNING TO ALL MN
TERMINALS. THIS SCENARIO SEEMS VERY PLAUSIBLE GIVEN THE FACT THAT
WE ARE CURRENTLY SEEING SCT ACTIVITY CLEAR DOWN INTO NC NEB. THE
ATMO HAS ALREADY TIPPED ITS HAND WHEN IT COMES TO FOG AT EAU...SO
HAVE LEFT THEM DOWN THE REST OF THE NIGHT. WITH THAT SAID...THERE
IS STILL A FAIR AMOUNT OF CLOUD COVER IN THE 050-080 LEVEL IN ERN
MN INTO WRN WI...WHICH MAY LEAD TO A BIT OF VARIABILITY IN THE
VSBYS AT RNH/EAU AS THEY SKIP BETWEEN 050-080 CLOUDS AND CLEAR
SKIES /WHICH WILL BE ACCOMPANIED BY FOG/. STILL A GOOD DEGREE OF
VARIABILITY WITH THE 00Z CAMS IN TERMS OF AFTERNOON
CONVECTION...BUT FORECAST SOUNDINGS DO SHOW A GOOD DEGREE OF
CAPPING TO OVERCOME FIRST...SO DID DELAY AFTERNOON TS MENTION AN
HOUR OR TWO FROM WHAT THE 00Z TAF HAD. IN ADDITION...REMOVED THE
AFTERNOON TS MENTION AT AXN...WITH AXN LOOKING TO MOST LIKELY BE
WEST OF THAT ROUND OF STORMS.
KMSP...BEGINNING TO GAIN CONFIDENCE IN AT LEAST SCT SHRA/TSRA IN
THE METRO AREA THIS MORNING...SO HAVE STARTED WITH INTRODUCING A
VCSH GROUP. BY 9Z...SHOULD HAVE A BETTER FEEL FOR WHETHER OR NOT
WE WILL SEE ANYTHING...SO WILL WAIT FOR THAT AMD TO SEE IF WE NEED
ANY STRONGER SHRA/TSRA MENTION. 00Z TAF LOOKED TO HAVE GOOD TIMING
FOR POTENTIAL AFTERNOON TSRA...SO STUCK WITH THAT. IS POTENTIAL
THAT MSP COULD GET SPLIT BY ACTIVITY TODAY...WITH STRONGER
ACTIVITY REMAINING SOUTH OF THE FIELD WITH BETTER LLJ FORCING DOWN
IN IOWA AND GOING NORTH OF THE FIELD...CLOSER TO THE SFC LOW THAT
WILL BE GOING ACROSS NRN MN. STILL...GIVEN THE STRENGTH OF THE
FRONT/FORCING...ODDS LOOK BETTER THAT MSP WILL SEE SOME TSRA
ACTIVITY THAN STORMS MISSING THE AIRPORT.
/OUTLOOK FOR KMSP/
MON...MVFR/TSRA ENDING EARLY. VFR BY AFTERNOON WINDS WNW 5-10 KTS.
TUE...VFR. WINDS WSW 5-10 KTS.
WED...VFR. CHC MVFR/TSRA LATE. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1252 AM CDT SUN AUG 31 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 242 PM CDT SAT AUG 30 2014
WEAK CONVERGENCE ZONE ALONG WITH MLCAPES AROUND 500 J/KG HAD
GENERATED A FEW SHRA ACROSS SOUTHERN MN TODAY. BOUNDARY LAYER
MOISTURE REMAINS ROBUST...SO CLOUDS HAVE BEEN SLOW TO ERODE DURING
THE TYPICAL DIURNAL AFTERNOON TIME FRAME. AS WINDS REMAIN WEAK AND
CYCLONIC CONTINUES DURING THE LATE AFTERNOON/EARLY EVENING...THESE LOW
CLOUDS MAY HOLD ON UNTIL LATER TONIGHT. ONCE WINDS SHIFT TO THE
SOUTHEAST AHEAD OF A DEEPENING AREA OF LOW PRESSURE ACROSS SD
LATER TONIGHT...ANY LOW CLOUDS SHOULD QUICKLY MOVE OUT OR DISSIPATE.
SOME FOG MAY DEVELOP ACROSS WC WI AS THIS AREA WILL BE LAST TO SEE
BOUNDARY LAYER MOISTURE RETREAT ALONG WITH WEAK MIXING IN THE
BOUNDARY LAYER.
A STRONG JET STREAM MOVING INTO THE PACIFIC NW TODAY WILL SET THE
STAGE FOR A VERY ACTIVE SUNDAY AFTERNOON/EVENING ACROSS THE UPPER
MIDWEST. BOTH AMPLE MOISTURE AND INCREASING SHEAR VALUES...ALONG A
DEEPENING AREA OF LOW PRESSURE ACROSS THE NORTHERN PLAINS...SHOULD
LEAD TO WIDESPREAD THUNDERSTORMS DEVELOPMENT BY THE LATE AFTERNOON
AHEAD OF A COLD FRONT. THERE REMAINS SOME DIFFERENCES IN THE
MODELS IN TERMS OF STRENGTH OF THE LLJ ALONG WITH THE UPPER LEVEL
JET CORE TO CONCLUDE WIDESPREAD SEVERE WX ACROSS THE UPPER
MIDWEST. THE UPPER JET CORE...WHICH IS EXPECTED TO BECOME A JET
COUPLET FROM THE NORTHERN AND SOUTHERN JET STREAMS...SHOULD LEAD
TO STRONG UPPER LEVEL DIFFLUENCE BY SUNDAY EVENING. AGAIN...MODELS
HAVE SOME DIFFERENCES IN THIS JET COUPLET WHICH LEADS TO
DIFFERENCES IN TIMING AND PLACEMENT OF THE HIGHER QPF AMOUNTS. IN
ADDITION...RESIDUAL CLOUD COVER FROM DECAYING MORNING TSRA COULD LIMIT
FULL AFTERNOON ISOLATION. THE BEST AREA FOR BOTH JET STRUCTURE/HIGHER
INSTABILITY AND SHEAR VALUES REMAIN ACROSS IOWA. FAR SC/SW MN
COULD ALSO BE IN THIS AREA OF HIGHER SVR WX POTENTIAL. LATER
SHIFTS WILL NEED MONITOR STRENGTH OF THIS JET ALONG WITH TSRA
DEVELOPMENT TOWARD MORNING.
IN ADDITION TO THE SVR WX THREAT...PWATS VALUES RISE INTO THE 1.5"
RANGE. IF ANY TSRA BEGIN TO TRAIN OR BACK BUILD...FLASH FLOODING
IS POSSIBLE...ESPECIALLY ONCE THE LLJ INCREASES DURING THE EVENING
HRS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 242 PM CDT SAT AUG 30 2014
POTENT COLD FRONT WILL HAVE SHIFTED THROUGH MUCH OF THE MPX CWFA BY
DAYBREAK MON MORNING...WITH IT PROGRESSING JUST BARELY INTO WRN WI
AND SERN MN. SOME LINGERING SHOWERS/TSTMS WILL LIKELY BE ONGOING IN
FAR ERN PORTIONS OF THE CWFA AT THE START OF THIS PERIOD BUT
STRENGTH WILL BE FAIRLY WEAK...MEANING THAT ANY SEVERE POTENTIAL
WILL HAVE BEEN TAPPED BY THIS POINT. SUPPORTING THIS FACT IS THAT
THE UPPER LEVEL TROF AXIS WILL BE E OF THE CWFA AND THE FRONT WILL
BE RATHER STRETCHED OUT BETWEEN THE MAIN LOW PRES CENTER OVER WRN
ONTARIO PROVINCE AND A SECONDARY LOW PRES CENTER OVER KS. HIGH
PRES WILL THEN NUDGE IN FROM THE CENTRAL PLAINS WHILE FLOW ALOFT
IS MAINLY ZONAL WNW-ESE. A FEW BUCKLES IN THE FLOW WITHIN A
PERSISTENTLY DEEP MOIST ATMO MAY PRODUCE ISOLATED SHOWERS FROM TIME TO
TIME LATE MON THRU MUCH OF WED. THIS AREA OF HIGH PRES WILL SHIFT
E INTO THE MID-MISS RIVER VALLEY THEN OHIO VALLEY BY WED MORNING...
ALLOWING FOR A WARMER AND MORE MOIST SLY RETURN FLOW TO DEVELOP BY
MIDDAY WED.
THE ADDITIONAL MOISTURE WILL PRECEDE THE ARRIVAL OF A SLOW-MOVING
LOW PRES CENTER FROM THE NRN ROCKIES WED NIGHT. THIS LOW WILL
STALL OUT OVER THE NRN PLAINS...HELPING SET UP A SFC FRONTAL
BOUNDARY EXTENDING FROM WRN MN ACROSS THE ROCKIES. THIS BOUNDARY
WILL ACT AS A LOW-LEVEL CONFLUENT ZONE AND AID IN PRECIPITATION
DEVELOPMENT THU THROUGH SAT. NOT LOOKING FOR A LOT IN THE WAY OF
QPF NOR STORM STRENGTH...BUT FINDING SOLID DRY TIME WILL BE
DIFFICULT DUE TO SCATTERED SHOWERS FOR MUCH OF THE LATTER PORTION
OF THE WEEK. CANNOT SAY ANY DAY WILL BE A WASHOUT ATTM...BUT ALSO
HARD TO PINPOINT ONE TIMEFRAME OVER ANOTHER FOR BEST TIMING OF
PRECIPITATION.
TEMPERATURES LOOK TO GO ON A SLOW WARMING TREND THRU THE
WORKWEEK...CLIMBING THROUGH THE MID-UPR 70S INTO THE LWR 80S BY
FRI. HOWEVER...THERE WILL BE PLENTY OF CLOUD/RAIN COMPLICATIONS
WHICH ON SMALL SCALES MAY CREATE SOME VARIETY WITH MAX/MIN TEMPS.
BY SAT... THIS LOW PRES COMPLEX WILL SHIFT S AND E OF THE MPX
CWFA...ALLOWING FOR A COOLING OF TEMPERATURES FOR NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1233 AM CDT SUN AUG 31 2014
WITH THE HRRR ALONG WITH VIRTUALLY ALL OTHER CAMS SHOWING A BAND
OF SHRA/TSRA WORKING ACROSS MN WITH INITIAL ARRIVAL OF THE
LLJ...STARTED TO INTRODUCE VCSH IN THE MORNING TO ALL MN
TERMINALS. THIS SCENARIO SEEMS VERY PLAUSIBLE GIVEN THE FACT THAT
WE ARE CURRENTLY SEEING SCT ACTIVITY CLEAR DOWN INTO NC NEB. THE
ATMO HAS ALREADY TIPPED ITS HAND WHEN IT COMES TO FOG AT EAU...SO
HAVE LEFT THEM DOWN THE REST OF THE NIGHT. WITH THAT SAID...THERE
IS STILL A FAIR AMOUNT OF CLOUD COVER IN THE 050-080 LEVEL IN ERN
MN INTO WRN WI...WHICH MAY LEAD TO A BIT OF VARIABILITY IN THE
VSBYS AT RNH/EAU AS THEY SKIP BETWEEN 050-080 CLOUDS AND CLEAR
SKIES /WHICH WILL BE ACCOMPANIED BY FOG/. STILL A GOOD DEGREE OF
VARIABILITY WITH THE 00Z CAMS IN TERMS OF AFTERNOON
CONVECTION...BUT FORECAST SOUNDINGS DO SHOW A GOOD DEGREE OF
CAPPING TO OVERCOME FIRST...SO DID DELAY AFTERNOON TS MENTION AN
HOUR OR TWO FROM WHAT THE 00Z TAF HAD. IN ADDITION...REMOVED THE
AFTERNOON TS MENTION AT AXN...WITH AXN LOOKING TO MOST LIKELY BE
WEST OF THAT ROUND OF STORMS.
KMSP...BEGINNING TO GAIN CONFIDENCE IN AT LEAST SCT SHRA/TSRA IN
THE METRO AREA THIS MORNING...SO HAVE STARTED WITH INTRODUCING A
VCSH GROUP. BY 9Z...SHOULD HAVE A BETTER FEEL FOR WHETHER OR NOT
WE WILL SEE ANYTHING...SO WILL WAIT FOR THAT AMD TO SEE IF WE NEED
ANY STRONGER SHRA/TSRA MENTION. 00Z TAF LOOKED TO HAVE GOOD TIMING
FOR POTENTIAL AFTERNOON TSRA...SO STUCK WITH THAT. IS POTENTIAL
THAT MSP COULD GET SPLIT BY ACTIVITY TODAY...WITH STRONGER
ACTIVITY REMAINING SOUTH OF THE FIELD WITH BETTER LLJ FORCING DOWN
IN IOWA AND GOING NORTH OF THE FIELD...CLOSER TO THE SFC LOW THAT
WILL BE GOING ACROSS NRN MN. STILL...GIVEN THE STRENGTH OF THE
FRONT/FORCING...ODDS LOOK BETTER THAT MSP WILL SEE SOME TSRA
ACTIVITY THAN STORMS MISSING THE AIRPORT.
/OUTLOOK FOR KMSP/
MON...MVFR/TSRA ENDING EARLY. VFR BY AFTERNOON WINDS WNW 5-10 KTS.
TUE...VFR. WINDS WSW 5-10 KTS.
WED...VFR. CHC MVFR/TSRA LATE. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...JPC
AVIATION...MPG
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
850 PM CDT MON SEP 1 2014
.UPDATE...
TONIGHT WILL BE QUIET AS CONVECTION FROM EARLIER SURGE OF MOISTURE
MOVING TO THE N HAS WINDED DOWN. PWATS HAVE CLIMBED TO ~2.1-2.2
INCHES IN REGIONAL SOUNDINGS/BLENDED SATELLITE TOTALS AND SOME OF
THESE HIGHER CLOUDS COULD LINGER INTO THE EVENING. LEFT ONLY WORDING
OF SOME SHOWERS IN THE FAR SW BUT ENDING BY 02Z. EXPECTING CLOUDS TO
LINGER IN THE AREA BUT SLOWLY DISSIPATE IN THE S/SW AS THE RUC/HRRR
INDICATE SOME MID LEVEL DRYING. AREAS THAT RECEIVED RAINFALL COULD
HAVE SOME PATCHY DENSE FOG...ESPECIALLY IN THE S/SE NEAR
MCB/HBG...BUT NOT EXPECTING IT TO BE WIDESPREAD ENOUGH TO MENTION IN
WX GRIDS DUE TO WIDESPREAD CLOUDINESS. HRRR DOES INDICATES SOME LOW
STRATUS MOVING BACK IN AFTER 06Z TUESDAY AND ADJUSTED SKY GRIDS
ACCORDINGLY. ADJUSTED LOWS SLIGHTLY UPWARD ACROSS THE AREA DUE TO
LINGERING CLOUDS. TWEAKED HOURLY TEMPS/DEWPOINTS TO CURRENT TRENDS.
REST OF THE FORECAST IS ON TRACK. /DC/
&&
.AVIATION...LATE TONIGHT ANTICIPATE WIDESPREAD MVFR TO LOCALLY IFR
CONDITIONS TO DEVELOP BY DAYBREAK TUESDAY. POTENTIAL FOR LOCALLY
DENSE FOG AND/OR IFR FLIGHT CATS IS HIGHEST AT PIB/HBG AREA OF THE
PINE BELT. FLIGHT CATS WILL IMPROVE THROUGH THE MORNING
TOMORROW...AS IS TYPICAL...WITH MORE MORE SCATTERED AFTERNOON
SHOWERS AND STORMS ANTICIPATED LATER TUESDAY. /BB/EC/
&&
.PREV DISCUSSION... /ISSUED 330 PM CDT MON SEP 1 2014/
SHORT TERM...THE MORNING SOUNDINGS SHOWED DRIER AIR ALOFT OVER THE
CWA BUT THE BLENDED TOTAL PRECIPITABLE WATER PRODUCT SHOWS TWO INCH
PWS SURGING BACK NORTH OVER THE SOUTHWEST TWO THIRDS OF OUR CWA.
THIS INCREASE IN DEEP MOISTURE WAS COMBINING WITH TEMPERATURES IN
THE LOW TO MID 90S TO DEVELOP A LITTLE GREATER COVERAGE OF SHOWERS
AND THUNDERSTORMS THIS AFTERNOON. HAVE INCREASED POPS THIS AFTERNOON
ACROSS MUCH OF THE AREA ALTHOUGH ISOLATED COVERAGE IS STILL EXPECTED
IN THE NORTHEAST. CONVECTION WILL DISSIPATE EARLY THIS EVENING.
OVERNIGHT TEMPERATURES WILL AGAIN BOTTOM OUT A LITTLE ABOVE
NORMAL...IN THE MID 70S AT MOST SITES. A WEAK SURFACE RIDGE WILL
NOSE ACROSS THE OUR CWA FROM THE EAST THROUGH WEDNESDAY WHILE A
RATHER FLAT MID LEVEL RIDGE RESIDES OVERHEAD. THIS WILL RESULT IN A
PERSISTENCE FORECAST FOR THE SHORT TERM WITH WARMER THAN NORMAL
TEMPERATURES THROUGH THE PERIOD. BY TUESDAY PWS WILL BE BACK AT OR
ABOVE TWO INCHES AREAWIDE. IN THE ABSENCE OF SIGNIFICANT MORNING
CLOUDINESS...TEMPERATURES WILL WARM UP RAPIDLY. THE WARM
TEMPERATURES WILL COMBINE WITH THE MOIST AIRMASS FOR SCATTERED
COVERAGE OF AFTERNOON AND EVENING STORMS. IT WILL BE HARD TO RULE
OUT A STRONG THUNDERSTORM OR TWO BUT OVERALL...PARAMETERS DO NOT
LOOK THAT FAVORABLE FOR WET MICROBURSTS THE NEXT TWO AFTERNOONS.
/22/
LONG TERM...THURSDAY THROUGH SUNDAY...GFS/ECMWF IN AGREEMENT THIS
PERIOD IN THAT PATTERN OVER THE LOWER CONUS WILL BE DOMINATED BY
FLAT RELATIVELY WEAK DEEP LAYERED RIDGE. AS MID/UPPER RIDGE AXIS
LOOKS TO REMAIN ANCHORED OVER NORTH MS...FLOW OVER THE AREA WILL
REMAIN EASTERLY AND AFFECTED BY ANY WAVES MOVING ALONG THE GULF
COAST. LOW LEVEL FLOW WILL REMAIN SOUTHERLY AS WELL SERVING TO KEEP
MOISTURE PLENTIFUL WITH PW/S REMAINING AROUND 2 INCHES.
HARD TO FIND ANY SIGNIFICANT WAVES IN THE FLOW DURING THIS PERIOD.
WHILE THE LOWER LEVELS LOOK TO BENEFIT MOST FROM THE WARMING FROM
THE RIDGE...MID/UPPER LEVEL TEMPS REMAIN SOMEWHAT COOL (NEAR -10C AT
H5) ALLOWING FOR AFTERNOON VERTICAL TOTALS IN THE MID 20S. BELIEVE
ISOLATED/SCATTERED CONVECTION WILL DOMINATE EACH
AFTERNOON/EVENING...MOST NUMEROUS IN THE SOUTH. SEA BREEZE ACTIVITY
LOOKS TO ENHANCE CONVECTION OVER THE SOUTH...BUT WEAK ONSHORE FLOW
SHOULD LIMIT ITS NORTHWARD EXTENT EACH DAY.
A WEAK FRONTAL BOUNDARY LOOKS TO DIP INTO NORTHERN MS ON SUNDAY
SERVING TO INCREASE CONVECTIVE POTENTIAL OVER THE NORTH BY THAT
TIME./26/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 74 94 73 95 / 12 39 23 31
MERIDIAN 73 94 71 95 / 9 28 24 29
VICKSBURG 74 94 72 94 / 12 43 20 30
HATTIESBURG 74 95 75 96 / 12 33 24 33
NATCHEZ 74 92 74 93 / 13 44 22 30
GREENVILLE 75 93 73 95 / 9 41 19 30
GREENWOOD 74 94 73 95 / 7 41 24 35
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/BB/EC/22/26
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
357 PM CDT Sun Aug 31 2014
.SHORT TERM...(This Evening through Wednesday Afternoon)
Issued at 357 PM CDT SUN AUG 31 2014
Afternoon water vapor imagery showing long advertised Pacific trough
digging into the central Plains this afternoon...with strong
shortwave energy now seen entering western Nebraska. Strengthening
wind fields along the southern edge of this feature have advected
Mexican Plateau air /i.e. elevated mixed layer/ east across the
central/southern Plains as seen on the latest 7.4 micron water vapor
GOES sounder channel. Latest RUC analysis shows 7-500 mb lapse rates
approaching 9C/km across western Kansas and Nebraska...and fcst
models suggest this mid-level airmass will continue tracking east
into our region overnight. Along the surface...latest analysis shows
a developing leeside low across southeastern Colorado...with a
northward extending frontal boundary draped across the Plains which
then joins the main area of low pressure now found along the
Minnesota/Manitoba border. With time this evening...aforementioned
boundary will progress eastward as upstream troughing continues to
settle into the central and southern Plains. Airmass ahead of both
the cold front and upper wave continues to destabilize with latest
SPC meso graphics yielding as much as 3500 joules of MLCAPE between
KC and Topeka. Most importantly however...deep layered shear will
continue increasing as well as mid- level wind max moves into the
area overnight. All said...ingredients appear to be coming together
for a fairly active evening and overnight period.
Latest radar trends now showing developing cells across north-central
Kansas along the previously mentioned frontal boundary. Storms
should continue to fire this afternoon before gradually spreading east
through the early evening and overnight. As has been advertised in
recent days quite well by numerical models...isolated convection to
our west and north will likely congeal into a forward propagating MCS
this evening just before it enters northwestern Missouri. As this
occurs...deep layered shear will continue to strengthen as a low-
level jet increases to nearly 50 kts directly overhead. This poses
two potential issues for our region:
1) Maintenance of ongoing severe weather as cold pool continues to
track southeast with time into northwest Missouri/northeast Kansas
2) Increasing likelihood for developing heavy rain/possible flooding as
low-level jet ascends any convectively generated cold pools
The above said...main concerns severe-wise for our area will remain
strong damaging winds as cold pool for developing MCS tracks south
and east with time. Current thinking is damaging wind potential will
gradually decrease as storms approach the greater KC area...however
cannot rule out strong gusts in and around the metro during the late
evening hrs. Additionally...a low-end tornado threat does exist across
far northwest Missouri as strong updrafts continue to tilt horizontal
vorticity into the vertical along the leading edge of the cold pool
as it tracks south and east with time. For now...agree completely with
where SPC has the highest tornado threat /NW MO/ as further progress
to the south and east will likely result in a less favorable
environment due to nocturnal cooling/low-level stabilization effects.
In terms of hydro concerns...have elected to go with a flash flood
watch for much of northwest MO/northeast Kansas as potential exists
for training convection if an outflow boundary lays out across
central Missouri. As alluded to above...strength of developing low-
level jet is a little concerning especially when PWAT values are
expected to increase to anywhere between 2-3 standard deviations
above normal as main front approaches. HPC QPF shows a 2+ inch
bullseye directly west of KC which appears to be in favor of
developing training after midnight. Would rather play it safe hence
the current flash flood watch which runs from 2z this evening through
15z Monday morning.
Front to slowly settle south of the region during the early morning
hrs. Another round of strong to severe storms is possible on
Monday...primarly south of the the greater KC area as daytime
heating combines with still impressive wind fields aloft. For
tomorrow...more optimal timing may support isolated supercell
structures as opposed to tonight/s linear activity. Regardless...have
maintained likely pops for most areas south of I-70 during the
afternoon hrs.
Front to clear the area tomorrow night which should support a mostly
dry Tuesday. Front slowly expected to lift north as a warm front
through the day on Wednesday but minimal impacts expected as no
significant features are at play to enhance upward vertical motion.
Temps by then should begin to rise with low to mid 90s possible
Wednesday afternoon as southerly flow reinvades the area.
.LONG TERM...(Wednesday Evening through Sunday)
Issued at 357 PM CDT SUN AUG 31 2014
A little bit of everything during the extended portion of the
forecast. Storms early Wednesday, followed by a return of hot and
humid air until a cold front and more storms on Friday, then finally
some fall-like weather over the weekend.
Medium range models all on the same page with the overall pattern.
Mid-week zonal flow backs to the southwest in response to an upper
trough tracking east from the Northern Rockies through the Upper MS
Valley by Friday.
Elevated convection associated with a northward returning warm front
will affect the CWA early Wednesday followed by hot and humid air
spreading back into the region. This will likely last into Friday
when the southern extension of the Northern Plains upper trough
forces a cold front south and through the Mid MO River Valley by
Saturday morning. Moderately strong and broad area of high pressure
expanding southward will bring some much needed relief from the high
humidities.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday Morning)
Issued at 1231 PM CDT SUN AUG 31 2014
VFR conditions this afternoon will give way to increasing chances
for showers and storms by evening as a strong storm system moves
into the area. Right now...initial shwr/storm activity expected to
reach MCI as early as 4z...and STJ as early as 3z. As this moves
in...strong wind gusts may create SQ conditions before strong
convective outflow moves east of area terminals. Shwrs/storms likely
to continue through a good portion of the overnight as low-level jet
increases...and storms continuously redevelop along and north of
thunderstorm outflow. Additional showers and storms possible after
12z...however bulk of activity should be shifting south as main
frontal boundary continues to move through the area.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...FLASH FLOOD WATCH from 9 PM CDT this evening through Monday
morning FOR KSZ025-102>105.
MO...FLASH FLOOD WATCH from 9 PM CDT this evening through Monday
morning FOR MOZ001>005-011>014-020>022-028>030.
&&
$$
SHORT TERM...32
LONG TERM...MJ
AVIATION...32
AREA FORECAST DISCUSSION
NWS BILLINGS MT
901 AM MDT SUN AUG 31 2014
.UPDATE...
MINOR UPDATES TO THE FORECAST THIS MORNING...MAINLY TO SLIGHTLY
ADJUST HIGH TEMPERATURES UPWARD FOR THIS AFTERNOON. MAIN WAVE IS
TRACKING FARTHER SOUTH THAN ANTICIPATED...WHICH IS KEEPING RAIN
SHOWER ACTIVITY SUPPRESSED TO THE SOUTH ACROSS WYOMING THIS
MORNING. THUS EXPECT TEMPERATURES WILL BE ABLE TO RISE BETTER
THAN EXPECTED WITH THE LACK OF PRECIPITATION. STILL ANTICIPATE
SOME INSTABILITY SHOWERS TO DEVELOP BY THIS AFTERNOON...BUT THE
ACTIVITY WILL BE FAIRLY SCATTERED.
CHURCH
&&
.SHORT TERM...VALID FOR TDY AND MON...
BROAD CYCLONIC FLOW WILL CONTINUE TO PREVAIL OVER OUR REGION THE
NEXT COUPLE OF DAYS. WE WILL HAVE A COUPLE OF DISTURBANCES WITHIN
THE FLOW ALOFT TRACK THROUGH THE REGION PRODUCING PERIODS OF
SHOWERS AND SCATTERED THUNDERSHOWERS. A SEASONABLY COOL AIR MASS
WILL REMAIN ENTRENCHED OVER THE REGION AS WELL KEEPING HIGHS ABOUT
10 DEGREES COOLER THAN NORMAL.
AS FOR ADJUSTMENTS IN THIS PACKAGE...JET MAX ON THE FRONT END OF
BROADER TROUGH IS WEAKER THAN THE ONE ON THE BACKSIDE WHICH SHOULD
KEEP SOME OF THE ENERGY DIGGING SOUTH EARLY TODAY. THIS WILL KEEP
THE BEST LIFT GENERALLY SOUTH IN NW WYOMING. ONLY THE RAP HAS
PICKED UP ON THIS SO FAR WITH THE GFS/WRF/ECMWF ALL OVERPLAYING
THE PRECIPITATION TOO FAR NORTH. HOWEVER...WE WILL SEE
INSTABILITY SHOWERS DEVELOP AS THE COLD POOL MOVES OVER US THIS
AFTERNOON. WE MAY SEE A BETTER CHANCE OF PRECIPITATION ON THIS
SIDE OF THE STATELINE BY AFTERNOON AS JET STREAM BUCKLES NORTH
WITH EASTWARD MOVEMENT OF UPPER TROUGH AXIS. SO HAVE ADJUSTED
HIGHEST POPS SOUTHWARD THIS MORNING...AND HIT THE SE SECTION
HARDEST LATE MORNING TO THIS AFTERNOON. ANOTHER SHORT WAVE COMES
THROUGH THIS EVENING AND AFFECTS MAINLY OUR WESTERN TERRAIN BEFORE
SPREADING SHOWERS TO THE SOUTHEAST THROUGH MONDAY. TEMPERATURES
WILL REMAIN ON THE COOL SIDE WITH LITTLE CHANGE TO INHERITED
FORECASTS. BT
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
RELATIVELY MINOR CHANGES TO THE EXTENDED PERIOD THIS MORNING.
ALTHOUGH MODELS ARE IN GOOD AGREEMENT WITH REGARD TO THE OVERALL
PATTERN...TIMING REMAINS A BIT OF AN ISSUE...AND LITTLE HAS
CHANGES FROM PREVIOUS MODELS RUNS. THE TIMING PROBLEMS HAVE
NECESSITATED A MORE BROAD BRUSH APPROACH TO POPS THROUGHOUT THE
PERIOD.
THE EXTENDED FORECAST REMAINS CONSISTENT...STARTING OFF QUIET FOR
WEDNESDAY...WITH ZONAL DOWNSLOPE FLOW ACROSS THE AREA. CONDITIONS
BEGIN TO CHANGE LATE WEDNESDAY AS SYSTEM OVER WESTERN CANADA DIGS
SOUTH AND FLOW TURNS SOUTHWEST OVER MONTANA. A COLD FRONT ALSO
PUSHES INTO THE REGION WEDNESDAY INCREASING THE CHANCES FOR
AFTERNOON AND EVENING THUNDERSTORMS. HAVE EXPANDED POPS COVERAGE
WEDNESDAY EVENING/NIGHT. BROAD TROF REMAINS IN CONTROL OVER THE
REGION INTO NEXT WEEKEND...WHICH KEEPS KEEPS SLIGHT PRECIP
POTENTIAL IN PLACE THROUGHOUT THE PERIOD AS WELL. PERSISTENCE OF
TROF WILL KEEP DAYTIME TEMPS WELL BELOW SEASONAL AVERAGE
THROUGHOUT THE EXTENDED PERIOD...WITH 60S AND 70S THROUGHOUT THE
PERIOD. AAG
&&
.AVIATION...
SCATTERED SHOWERS ARE EXPECTED ACROSS MUCH OF THE REGION TODAY AS
ANOTHER DISTURBANCE CROSSES THE AREA. VFR CONDITIONS WILL PREVAIL
WITH LOCAL MVFR AND OCCASIONAL MOUNTAIN OBSCURATIONS NEAR SHOWER
ACTIVITY. CHAMBERS
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 071 051/070 050/078 054/077 050/069 049/069 050/074
3/T 32/T 00/U 12/T 22/T 22/T 22/T
LVM 068 044/070 043/079 046/077 043/068 044/069 045/076
3/T 42/T 00/U 12/T 22/T 22/T 23/T
HDN 072 051/072 050/080 053/081 051/072 051/073 050/077
2/T 32/T 00/U 12/T 22/T 22/T 22/T
MLS 074 052/074 052/079 054/080 053/071 053/072 052/075
2/T 12/T 00/U 11/U 12/T 22/T 22/T
4BQ 071 051/071 051/080 053/083 052/072 051/073 051/076
4/T 23/T 00/U 12/T 22/T 22/T 22/T
BHK 072 050/072 048/077 051/080 050/073 049/070 049/073
4/T 12/T 00/U 12/T 22/T 22/T 22/T
SHR 068 047/069 046/080 050/083 049/073 048/075 048/078
5/T 33/T 00/U 12/T 22/T 22/T 23/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
330 AM MDT SUN AUG 31 2014
.SHORT TERM...VALID FOR TDY AND MON...
BROAD CYCLONIC FLOW WILL CONTINUE TO PREVAIL OVER OUR REGION THE
NEXT COUPLE OF DAYS. WE WILL HAVE A COUPLE OF DISTURBANCES WITHIN
THE FLOW ALOFT TRACK THROUGH THE REGION PRODUCING PERIODS OF
SHOWERS AND SCATTERED THUNDERSHOWERS. A SEASONABLY COOL AIR MASS
WILL REMAIN ENTRENCHED OVER THE REGION AS WELL KEEPING HIGHS ABOUT
10 DEGREES COOLER THAN NORMAL.
AS FOR ADJUSTMENTS IN THIS PACKAGE...JET MAX ON THE FRONT END OF
BROADER TROUGH IS WEAKER THAN THE ONE ON THE BACKSIDE WHICH SHOULD
KEEP SOME OF THE ENERGY DIGGING SOUTH EARLY TODAY. THIS WILL KEEP
THE BEST LIFT GENERALLY SOUTH IN NW WYOMING. ONLY THE RAP AND HRRR HAS
PICKED UP ON THIS SO FAR WITH THE GFS/WRF/ECMWF ALL OVERPLAYING
THE PRECIPITATION TOO FAR NORTH. HOWEVER...WE WILL SEE INSTABILITY
SHOWERS DEVELOP AS THE COLD POOL MOVES OVER THE WEST THIS
AFTERNOON. WE MAY SEE A BETTER CHANCE OF PRECIPITATION ON THIS
SIDE OF THE STATELINE BY AFTERNOON AS ENERGY TURNS NORTHEAST ON
TROUGHS FRONT SIDE. SO HAVE ADJUSTED HIGHEST POPS SOUTHWARD THIS
MORNING...AND HIT THE SE SECTION HARDEST LATE MORNING TO THIS
AFTERNOON. ANOTHER SHORT WAVE COMES THROUGH THIS EVENING AND
AFFECTS MAINLY OUR WESTERN TERRAIN BEFORE SPREADING SHOWERS TO THE
SOUTHEAST THROUGH MONDAY. TEMPERATURES WILL REMAIN ON THE COOL
SIDE WITH LITTLE CHANGE TO INHERITED FORECASTS. BT
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
RELATIVELY MINOR CHANGES TO THE EXTENDED PERIOD THIS MORNING.
ALTHOUGH MODELS ARE IN GOOD AGREEMENT WITH REGARD TO THE OVERALL
PATTERN...TIMING REMAINS A BIT OF AN ISSUE...AND LITTLE HAS
CHANGES FROM PREVIOUS MODELS RUNS. THE TIMING PROBLEMS HAVE
NECESSITATED A MORE BROAD BRUSH APPROACH TO POPS THROUGHOUT THE
PERIOD.
THE EXTENDED FORECAST REMAINS CONSISTENT...STARTING OFF QUIET FOR
WEDNESDAY...WITH ZONAL DOWNSLOPE FLOW ACROSS THE AREA. CONDITIONS
BEGIN TO CHANGE LATE WEDNESDAY AS SYSTEM OVER WESTERN CANADA DIGS
SOUTH AND FLOW TURNS SOUTHWEST OVER MONTANA. A COLD FRONT ALSO
PUSHES INTO THE REGION WEDNESDAY INCREASING THE CHANCES FOR
AFTERNOON AND EVENING THUNDERSTORMS. HAVE EXPANDED POPS COVERAGE
WEDNESDAY EVENING/NIGHT. BROAD TROF REMAINS IN CONTROL OVER THE
REGION INTO NEXT WEEKEND...WHICH KEEPS KEEPS SLIGHT PRECIP
POTENTIAL IN PLACE THROUGHOUT THE PERIOD AS WELL. PERSISTENCE OF
TROF WILL KEEP DAYTIME TEMPS WELL BELOW SEASONAL AVERAGE
THROUGHOUT THE EXTENDED PERIOD...WITH 60S AND 70S THROUGHOUT THE
PERIOD. AAG
&&
.AVIATION...
SCATTERED SHOWERS ARE EXPECTED ACROSS MUCH OF THE REGION TODAY AS
ANOTHER DISTURBANCE CROSSES THE AREA. AREAS OF MVFR AND FREQUENT
MOUNTAIN OBSCURATIONS CAN BE EXPECTED THROUGHOUT THE DAY. AAG
&&
.PRELIMINARY POINT TEMP/POPS...
TDY MON TUE WED THU FRI SAT
-------------------------------------------------------
BIL 069 051/070 050/078 054/077 050/069 049/069 050/074
3/T 32/T 00/U 12/T 22/T 22/T 22/T
LVM 066 044/070 043/079 046/077 043/068 044/069 045/076
4/T 42/T 00/U 12/T 22/T 22/T 23/T
HDN 071 051/072 050/080 053/081 051/072 051/073 050/077
3/T 32/T 00/U 12/T 22/T 22/T 22/T
MLS 074 052/074 052/079 054/080 053/071 053/072 052/075
2/T 22/T 00/U 11/U 12/T 22/T 22/T
4BQ 070 051/071 051/080 053/083 052/072 051/073 051/076
4/T 23/T 00/U 12/T 22/T 22/T 22/T
BHK 072 050/072 048/077 051/080 050/073 049/070 049/073
4/T 12/T 00/U 12/T 22/T 22/T 22/T
SHR 066 047/069 046/080 050/083 049/073 048/075 048/078
5/T 33/T 00/U 12/T 22/T 22/T 23/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1206 PM EDT SUN AUG 31 2014
.SYNOPSIS...
A SLOW MOVING TROUGH OF LOW PRESSURE WILL PRODUCE SHOWERS AND A
FEW THUNDERSTORMS TODAY BEFORE SLOWLY TAPERING OFF FROM NORTHWEST
TO SOUTHEAST THIS AFTERNOON. IT WILL REMAIN MUGGY ALTHOUGH
EXTENSIVE CLOUD COVER WILL KEEP TEMPERATURES LOWER THAN YESTERDAY.
A FEW SPOTTY SHOWERS AND THUNDERSTORMS ARE POSSIBLE ON LABOR
DAY...BUT THE MAJORITY OF THE DAY SHOULD BE RAIN FREE WITH
TEMPERATURES WARMING BACK TO A LITTLE ABOVE AVERAGE.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IMAGERY LATE THIS MORNING SHOWS A SOLID AREA OF RAIN ACROSS
CENTRAL NEW YORK...JUST ABOUT TO EXIT EAST OF OUR CWA. BEHIND
THIS...BROKEN LINES OF SHOWERS WITH EMBEDDED THUNDERSTORMS HAVE
DEVELOPED AHEAD OF A WIND SHIFT BOUNDARY WHICH EXTENDS FROM SW-NE
AND IS LOCATED NEAR BUFFALO AT 1100 AM. THIS BOUNDARY WILL
CONTINUE TO MOVE EAST IN ASSOCIATION WITH A MID LEVEL TROUGH. THE
12Z BUF SOUNDING HAS AN IMPRESSIVE 1.83 INCH PWAT...SO SHOWERS AND
THUNDERSTORMS WHICH DO DEVELOP AHEAD OF THIS BOUNDARY WILL PRODUCE
BRIEF HEAVY DOWNPOURS. FOR THE MOST PART...THE PROGRESSIVE NATURE
OF THE BOUNDARY WILL MITIGATE FLOOD POTENTIAL...HOWEVER A
DEVELOPING AREA OF HEAVY RAIN SHOWERS ACROSS LAKE ERIE MAY HAVE
THE POTENTIAL TO PRODUCE LOCALIZED FLOODING IN CHAUTAUQUA COUNTY
THROUGH MID AFTERNOON.
IT IS STILL FAIRLY MOIST BEHIND THIS BOUNDARY...AND WITH A LAKE
BREEZE CONVERGENCE BOUNDARY EXPECTED TO DEVELOP NEAR THE SOUTH
SHORES OF LAKE ONTARIO THERE COULD BE A FEW SHOWERS OR
THUNDERSTORMS WHICH DEVELOP ON THIS BOUNDARY. HOWEVER...MOST
MESOSCALE GUIDANCE FROM THE HRRR TO NAM/RGEM FOCUS THE STEADIEST
SHOWERS ACROSS EAST OF EACH LAKE...OUT AHEAD OF THE BOUNDARY.
SOUTHWESTERLY WINDS WILL PICK UP ACROSS THE NIAGARA FRONTIER THIS
AFTERNOON...WHICH SHOULD PROVIDE AT LEAST A PARTIAL CLEARING BY
MIXING OUT LOW MOISTURE. TEMPERATURES ALOFT ARE STILL WARM...WITH
SURFACE TEMPERATURES LIKELY TO REACH 80 IN ANY AREAS WHICH GET
PROLONGED SUNSHINE. SOUTHERN AND EASTERN PORTIONS OF THE CWA
SHOULD STAY STUCK IN THE CLOUDS...WITH HIGHS AVERAGING IN THE MID
70S.
TONIGHT SHOWERS ACROSS THE SOUTHERN TIER AND CENTRAL NY WILL
CONTINUE TO SLOWLY DIMINISH. ENOUGH INSTABILITY MAY DEVELOP IN THE
WAKE OF THIS MAIN RAIN AREA TO ALLOW SCATTERED THUNDERSTORMS TO FORM
DURING THE LATE AFTERNOON AND EARLY EVENING ACROSS THE NIAGARA
PENINSULA. IF THEY MATERIALIZE...A FEW MAY MAKE IT INTO AREAS JUST
NORTH OF BUFFALO THIS EVENING. SCATTERED STORMS MAY ALSO FORM OVER
SOUTHEAST ONTARIO AND CROSS THE SAINT LAWRENCE INTO THE NORTH
COUNTRY THIS EVENING. OTHERWISE EXPECT SOME PARTIAL CLEARING
OVERNIGHT ON THE LAKE PLAINS. ACROSS THE HIGHER TERRAIN LOW LEVEL
MOISTURE AND WEAK UPSLOPE FLOW AND CONVERGENCE WILL LIKELY SUPPORT
EXPANDING LOW CLOUD COVER. EXPECT LOWS IN THE MID TO UPPER 60S ON
THE LAKE PLAINS AND LOWER TO MID 60S IN THE SOUTHERN TIER AND NORTH
COUNTRY.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A WARM AND STICKY AIRMASS WILL REMAIN ACROSS THE REGION ON
MONDAY...WITH MOST OF THE FORECAST AREA EXPERIENCING MAINLY DRY
CONDITIONS. HOWEVER THERE WILL BE THE CHANCE FOR SCATTERED SHOWERS
AND THUNDERSTORMS IN THE AFTERNOON AND EVENING...MAINLY ACROSS THE
INTERIOR SOUTHERN TIER WHERE THE BEST INSTABILITY WILL RESIDE. CAPE
VALUES BY LATER IN THE AFTERNOON ACROSS THIS REGION WILL RUN IN THE
1000-1500 J/KG RANGE WITH LI`S POSSIBLY AS LOW AS -4. HOWEVER WITH
WEAK 0-6KM BULK SHEAR (~20KTS) AND LACK OF A GOOD SURFACE TRIGGER
(ASIDE FROM A POSSIBLE LAKE BREEZE)...NOT EXPECTING ANY
THUNDERSTORMS TO REACH SEVERE LIMITS. INSTABILITY LOOKS LOWER ACROSS
THE REMAINDER OF THE AREA...AND THUS CONVECTIVE CHANCES LOOK MUCH
LOWER AS WELL. TEMPERATURES WILL AGAIN BE ON THE WARM SIDE WITH
HIGHS IN THE UPPER 70S TO LOWER 80S.
WITH THE LOSS OF DAYTIME HEATING MONDAY NIGHT MOST OF THE DIURNALLY
DRIVEN CONVECTION WILL DIMINISH IN COVERAGE...ALTHOUGH A FEW STORMS
MAY CONTINUE LATE INTO THE EVENING...ESPECIALLY ACROSS PORTIONS OF
THE SOUTHERN TIER. AT THE SAME TIME A COLD FRONT OVER THE UPPER
GREAT LAKES WILL BE ADVANCING TOWARD THE REGION AND BE LOCATED WEST
OF NEW YORK STATE BY TUESDAY MORNING. THAT SAID...MOST OF THE NIGHT
LOOKS TO REMAIN DRY...WITH PRECIP CHANCES STARTING TO INCREASE A BIT
ACROSS WESTERN NEW YORK TOWARD TUESDAY MORNING. ANOTHER MILD
NIGHT CAN BE EXPECTED WITH LOWS IN THE MID TO UPPER 60S FOR MOST
LOCATIONS THANKS TO DEEP SOUTHERLY FLOW OUT AHEAD OF THE APPROACHING
COLD FRONT.
LATEST GUIDANCE PACKAGE HAS THE COLD FRONT NOW MOVING A BIT SLOWER
THAN IN PREVIOUS RUNS. THIS IS MOST LIKELY DUE TO MOST OF THE MODELS
NOW COMING INTO AGREEMENT ON THE DEVELOPMENT OF LOW PRESSURE
SOMEWHERE IN THE OHIO VALLEY ALONG THE FRONT AND THEN TRACKING IT
NORTHEAST ALONG THE BOUNDARY WHICH WOULD SLOW IT DOWN A LITTLE.
THAT SAID...IT NOW APPEARS IT WILL TAKE THE BULK OF THE DAY TUESDAY
FOR THE COLD FRONT TO SWEEP ACROSS THE REGION WITH SHOWERS AN
THUNDERSTORMS LIKELY...WITH LOWER CHANCE POPS BY LATER IN THE DAY
ACROSS WESTERN NEW YORK. HIGH PRECIPITABLE WATER VALUES OF 1.7"-1.9"
TUESDAY AFTERNOON OFFER THE RISK OF HEAVY DOWNPOURS WITH ANY
THUNDERSTORM. SBCAPES OVER 1000 J/KG COMBINED WITH LIFTED INDEX
VALUES AT -4C TO -5C ALSO POINT TO THE POSSIBILITY OF STORMS. THE
MAIN DIFFERENCES FROM MONDAY ARE THAT 0-6KM BULK SHEAR VALUES LOOK
TO BE IN THE 40-45KT RANGE...AND ALSO HAVE THE SURFACE COLD FRONT
CROSSING THE FORECAST AREA WHICH WILL SERVE AS THE FOCAL POINT FOR
STORMS TO FIRE ALONG. ALL THIS SAID...LOOKS AS THOUGH THERE COULD BE
SOME STRONG STORMS...WITH A FEW STORMS POSSIBLY REACHING SEVERE
LIMITS. MAIN THREATS APPEAR TO BE GUSTY WINDS ASSOCIATED WITH BOWING
LINE SEGMENTS AND MARGINALLY SEVERE HAIL. ANOTHER WARM DAY ON TAP
WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
THE COLD FRONT WILL SLIDE SOUTH AND EAST OF THE FORECAST AREA
TUESDAY EVENING...TAKING THE SHOWERS AND STORMS WITH IT. ALTHOUGH A
FEW SHOWERS WILL STILL BE POSSIBLE DURING THE EVENING ACROSS EASTERN
AREAS...BUT EVEN HERE THINGS WILL DRY OUT LATER TUESDAY NIGHT AS
SURFACE HIGH PRESSURE STARTS TO BUILD EAST ACROSS NEW YORK STATE.
LOWS WILL BE GENERALLY IN THE UPPER 50S TO LOWER 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE WILL BUILD ACROSS THE
REGION WEDNESDAY AND THURSDAY BRINGING IN DRIER AIR AND TEMPERATURES
THAT WILL STILL AVERAGE AT OR JUST A BIT ABOVE NORMAL FOR EARLY
SEPTEMBER. HIGH PRESSURE WILL THEN SLIDE OFF THE NEW ENGLAND COAST
BY FRIDAY. THIS WILL PROVIDE MAINLY DRY CONDITIONS THROUGH
MIDWEEK...BEFORE THE NEXT FRONTAL SYSTEM APPROACHES FOR LATE IN THE
WEEK AND EARLY WEEKEND. TEMPERATURES WILL BE A BIT ABOVE SEASONAL
NORMALS WITH HIGHS IN THE UPPER 70S TO LOW 80S AND LOWS IN THE LOWER
60S.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
CONDITIONS HAVE LOWERED LATE THIS MORNING...WITH THE APPROACH OF A
SURFACE TROUGH AN IN HEAVIER RAIN SHOWERS. LOW VSBY IN RAIN
SHOWERS...AND A FEW EMBEDDED THUNDERSTORMS SHOULD BE
TEMPORARY. EXPECT A MIX OF MVFR/VFR CIGS AT BUF/IAG/ROC/ART WITH
THE SW WIND SHIFT...WHILE JHW IS LIKELY TO REMAIN IFR OR LOWER AND
THEN IMPROVE WITH THE WIND SHIFT.
TONIGHT ANY SHOWERS AND SCATTERED THUNDER ACROSS THE SOUTHERN TIER
WILL DIMINISH DURING THE EVENING. MAINLY VFR DURING THE EVENING WILL
GIVE WAY TO INCREASING AMOUNTS OF IFR IN LOW STRATUS OVERNIGHT WITH
EXTENSIVE LOW LEVEL MOISTURE FIELDS. EXPECT STRATUS TO FORM FIRST
ACROSS HIGHER TERRAIN...BUT MAY SPREAD TO THE LOWER ELEVATIONS OF
WESTERN NY AS WELL AFTER ABOUT 09Z. AREAS OF FOG AND IFR VSBY ARE
LIKELY ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER AND FINGER
LAKES AS WELL WHERE THE LOW STRATUS INTERSECTS THE HILLS.
OUTLOOK...
MONDAY...VFR/MVFR IN SCATTERED SHOWERS AND THUNDERSTORMS.
TUESDAY...SHOWERS AND THUNDERSTORMS LIKELY WITH ASSOCIATED BRIEF
MVFR/IFR. SOME STORMS MAY BE STRONG.
WEDNESDAY AND THURSDAY...VFR.
&&
.MARINE...
MODERATE SOUTHERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL CRAFT
ADVISORY CONDITIONS AT THE NORTHEAST END OF LAKE ONTARIO FROM GALLOO
ISLAND TO CAPE VINCENT THROUGH EARLY AFTERNOON BEFORE
DIMINISHING. LOW PRESSURE WILL MOVE ACROSS SOUTHERN QUEBEC TODAY
WITH WINDS BECOMING MORE SOUTHWEST ON THE LOWER LAKES. EXPECT
WINDS TO INCREASE ABRUPTLY ON LAKE ERIE THROUGH EARLY
AFTERNOON...WITH A 3 TO 6 HOUR PERIOD OF 15 TO 20 KNOT WINDS AND 3
TO 5 FOOT WAVES AS WINDS ALOFT SHIFT TO THE WSW AND MIX DOWN
AS THEY ENCOUNTER THE CHAUTAUQUA RIDGE. ALSO...THERE IS A
CONVERGENCE BOUNDARY ON LAKE ERIE WHICH HAS THE POTENTIAL TO
PRODUCE WATER SPOUTS THROUGH EARLY AFTERNOON. THIS POTENTIAL WILL
END AS THE BOUNDARY SLIDES FURTHER SOUTH AND OFF THE LAKE.
THE PRESSURE GRADIENT RELAXES ACROSS THE LOWER LAKES TONIGHT AS LOW
PRESSURE DISSIPATES OVER SOUTHEAST QUEBEC. THIS WILL ALLOW WINDS AND
WAVES TO SUBSIDE.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON
FOR LOZ045.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...APFFEL/HITCHCOCK
SHORT TERM...JM
LONG TERM...JM/WCH
AVIATION...APFFEL/HITCHCOCK
MARINE...APFFEL/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1112 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A SLOW MOVING TROUGH OF LOW PRESSURE WILL PRODUCE SHOWERS AND A
FEW THUNDERSTORMS TODAY BEFORE SLOWLY TAPERING OFF FROM NORTHWEST
TO SOUTHEAST THIS AFTERNOON. IT WILL REMAIN MUGGY ALTHOUGH
EXTENSIVE CLOUD COVER WILL KEEP TEMPERATURES LOWER THAN YESTERDAY.
A FEW SPOTTY SHOWERS AND THUNDERSTORMS ARE POSSIBLE ON LABOR
DAY...BUT THE MAJORITY OF THE DAY SHOULD BE RAIN FREE WITH
TEMPERATURES WARMING BACK TO A LITTLE ABOVE AVERAGE.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IMAGERY LATE THIS MORNING SHOWS A SOLID AREA OF RAIN ACROSS
CENTRAL NEW YORK...JUST ABOUT TO EXIT EAST OF OUR CWA. BEHIND
THIS...BROKEN LINES OF SHOWERS WITH EMBEDDED THUNDERSTORMS HAVE
DEVELOPED AHEAD OF A WIND SHIFT BOUNDARY WHICH EXTENDS FROM SW-NE
AND IS LOCATED NEAR BUFFALO AT 1100 AM. THIS BOUNDARY WILL
CONTINUE TO MOVE EAST IN ASSOCIATION WITH A MID LEVEL TROUGH. THE
12Z BUF SOUNDING HAS AN IMPRESSIVE 1.83 INCH PWAT...SO SHOWERS AND
THUNDERSTORMS WHICH DO DEVELOP AHEAD OF THIS BOUNDARY WILL PRODUCE
BRIEF HEAVY DOWNPOURS...BUT ARE LIKELY TO MOVE WITH THE BOUNDARY WHICH
SHOULD MITIGATE FLOOD POTENTIAL. IT IS STILL FAIRLY MOIST BEHIND
THIS BOUNDARY...AND WITH A LAKE BREEZE CONVERGENCE BOUNDARY
EXPECTED TO DEVELOP NEAR THE SOUTH SHORES OF LAKE ONTARIO THERE
COULD BE A FEW SHOWERS OR THUNDERSTORMS WHICH DEVELOP ON THIS
BOUNDARY. HOWEVER...MOST MESOSCALE GUIDANCE FROM THE HRRR TO
NAM/RGEM FOCUS THE STEADIEST SHOWERS ACROSS EAST OF EACH
LAKE...OUT AHEAD OF THE BOUNDARY.
SOUTHWESTERLY WINDS WILL PICK UP ACROSS THE NIAGARA FRONTIER THIS
AFTERNOON...WHICH SHOULD PROVIDE AT LEAST A PARTIAL CLEARING BY
MIXING OUT LOW MOISTURE. TEMPERATURES ALOFT ARE STILL WARM...WITH
SURFACE TEMPERATURES LIKELY TO REACH 80 IN ANY AREAS WHICH GET
PROLONGED SUNSHINE. SOUTHERN AND EASTERN PORTIONS OF THE CWA
SHOULD STAY STUCK IN THE CLOUDS...WITH HIGHS AVERAGING IN THE MID
70S.
TONIGHT SHOWERS ACROSS THE SOUTHERN TIER AND CENTRAL NY WILL
CONTINUE TO SLOWLY DIMINISH. ENOUGH INSTABILITY MAY DEVELOP IN THE
WAKE OF THIS MAIN RAIN AREA TO ALLOW SCATTERED THUNDERSTORMS TO FORM
DURING THE LATE AFTERNOON AND EARLY EVENING ACROSS THE NIAGARA
PENINSULA. IF THEY MATERIALIZE...A FEW MAY MAKE IT INTO AREAS JUST
NORTH OF BUFFALO THIS EVENING. SCATTERED STORMS MAY ALSO FORM OVER
SOUTHEAST ONTARIO AND CROSS THE SAINT LAWRENCE INTO THE NORTH
COUNTRY THIS EVENING. OTHERWISE EXPECT SOME PARTIAL CLEARING
OVERNIGHT ON THE LAKE PLAINS. ACROSS THE HIGHER TERRAIN LOW LEVEL
MOISTURE AND WEAK UPSLOPE FLOW AND CONVERGENCE WILL LIKELY SUPPORT
EXPANDING LOW CLOUD COVER. EXPECT LOWS IN THE MID TO UPPER 60S ON
THE LAKE PLAINS AND LOWER TO MID 60S IN THE SOUTHERN TIER AND NORTH
COUNTRY.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A WARM AND STICKY AIRMASS WILL REMAIN ACROSS THE REGION ON
MONDAY...WITH MOST OF THE FORECAST AREA EXPERIENCING MAINLY DRY
CONDITIONS. HOWEVER THERE WILL BE THE CHANCE FOR SCATTERED SHOWERS
AND THUNDERSTORMS IN THE AFTERNOON AND EVENING...MAINLY ACROSS THE
INTERIOR SOUTHERN TIER WHERE THE BEST INSTABILITY WILL RESIDE. CAPE
VALUES BY LATER IN THE AFTERNOON ACROSS THIS REGION WILL RUN IN THE
1000-1500 J/KG RANGE WITH LI`S POSSIBLY AS LOW AS -4. HOWEVER WITH
WEAK 0-6KM BULK SHEAR (~20KTS) AND LACK OF A GOOD SURFACE TRIGGER
(ASIDE FROM A POSSIBLE LAKE BREEZE)...NOT EXPECTING ANY
THUNDERSTORMS TO REACH SEVERE LIMITS. INSTABILITY LOOKS LOWER ACROSS
THE REMAINDER OF THE AREA...AND THUS CONVECTIVE CHANCES LOOK MUCH
LOWER AS WELL. TEMPERATURES WILL AGAIN BE ON THE WARM SIDE WITH
HIGHS IN THE UPPER 70S TO LOWER 80S.
WITH THE LOSS OF DAYTIME HEATING MONDAY NIGHT MOST OF THE DIURNALLY
DRIVEN CONVECTION WILL DIMINISH IN COVERAGE...ALTHOUGH A FEW STORMS
MAY CONTINUE LATE INTO THE EVENING...ESPECIALLY ACROSS PORTIONS OF
THE SOUTHERN TIER. AT THE SAME TIME A COLD FRONT OVER THE UPPER
GREAT LAKES WILL BE ADVANCING TOWARD THE REGION AND BE LOCATED WEST
OF NEW YORK STATE BY TUESDAY MORNING. THAT SAID...MOST OF THE NIGHT
LOOKS TO REMAIN DRY...WITH PRECIP CHANCES STARTING TO INCREASE A BIT
ACROSS WESTERN NEW YORK TOWARD TUESDAY MORNING. ANOTHER MILD
NIGHT CAN BE EXPECTED WITH LOWS IN THE MID TO UPPER 60S FOR MOST
LOCATIONS THANKS TO DEEP SOUTHERLY FLOW OUT AHEAD OF THE APPROACHING
COLD FRONT.
LATEST GUIDANCE PACKAGE HAS THE COLD FRONT NOW MOVING A BIT SLOWER
THAN IN PREVIOUS RUNS. THIS IS MOST LIKELY DUE TO MOST OF THE MODELS
NOW COMING INTO AGREEMENT ON THE DEVELOPMENT OF LOW PRESSURE
SOMEWHERE IN THE OHIO VALLEY ALONG THE FRONT AND THEN TRACKING IT
NORTHEAST ALONG THE BOUNDARY WHICH WOULD SLOW IT DOWN A LITTLE.
THAT SAID...IT NOW APPEARS IT WILL TAKE THE BULK OF THE DAY TUESDAY
FOR THE COLD FRONT TO SWEEP ACROSS THE REGION WITH SHOWERS AN
THUNDERSTORMS LIKELY...WITH LOWER CHANCE POPS BY LATER IN THE DAY
ACROSS WESTERN NEW YORK. HIGH PRECIPITABLE WATER VALUES OF 1.7"-1.9"
TUESDAY AFTERNOON OFFER THE RISK OF HEAVY DOWNPOURS WITH ANY
THUNDERSTORM. SBCAPES OVER 1000 J/KG COMBINED WITH LIFTED INDEX
VALUES AT -4C TO -5C ALSO POINT TO THE POSSIBILITY OF STORMS. THE
MAIN DIFFERENCES FROM MONDAY ARE THAT 0-6KM BULK SHEAR VALUES LOOK
TO BE IN THE 40-45KT RANGE...AND ALSO HAVE THE SURFACE COLD FRONT
CROSSING THE FORECAST AREA WHICH WILL SERVE AS THE FOCAL POINT FOR
STORMS TO FIRE ALONG. ALL THIS SAID...LOOKS AS THOUGH THERE COULD BE
SOME STRONG STORMS...WITH A FEW STORMS POSSIBLY REACHING SEVERE
LIMITS. MAIN THREATS APPEAR TO BE GUSTY WINDS ASSOCIATED WITH BOWING
LINE SEGMENTS AND MARGINALLY SEVERE HAIL. ANOTHER WARM DAY ON TAP
WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
THE COLD FRONT WILL SLIDE SOUTH AND EAST OF THE FORECAST AREA
TUESDAY EVENING...TAKING THE SHOWERS AND STORMS WITH IT. ALTHOUGH A
FEW SHOWERS WILL STILL BE POSSIBLE DURING THE EVENING ACROSS EASTERN
AREAS...BUT EVEN HERE THINGS WILL DRY OUT LATER TUESDAY NIGHT AS
SURFACE HIGH PRESSURE STARTS TO BUILD EAST ACROSS NEW YORK STATE.
LOWS WILL BE GENERALLY IN THE UPPER 50S TO LOWER 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE WILL BUILD ACROSS THE
REGION WEDNESDAY AND THURSDAY BRINGING IN DRIER AIR AND TEMPERATURES
THAT WILL STILL AVERAGE AT OR JUST A BIT ABOVE NORMAL FOR EARLY
SEPTEMBER. HIGH PRESSURE WILL THEN SLIDE OFF THE NEW ENGLAND COAST
BY FRIDAY. THIS WILL PROVIDE MAINLY DRY CONDITIONS THROUGH
MIDWEEK...BEFORE THE NEXT FRONTAL SYSTEM APPROACHES FOR LATE IN THE
WEEK AND EARLY WEEKEND. TEMPERATURES WILL BE A BIT ABOVE SEASONAL
NORMALS WITH HIGHS IN THE UPPER 70S TO LOW 80S AND LOWS IN THE LOWER
60S.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
CONDITIONS HAVE LOWERED LATE THIS MORNING...WITH THE APPROACH OF A
SURFACE TROUGH AN IN HEAVIER RAIN SHOWERS. LOW VSBY IN RAIN
SHOWERS...AND A FEW EMBEDDED THUNDERSTORMS SHOULD BE
TEMPORARY. EXPECT A MIX OF MVFR/VFR CIGS AT BUF/IAG/ROC/ART WITH
THE SW WIND SHIFT...WHILE JHW IS LIKELY TO REMAIN IFR OR LOWER AND
THEN IMPROVE WITH THE WIND SHIFT.
TONIGHT ANY SHOWERS AND SCATTERED THUNDER ACROSS THE SOUTHERN TIER
WILL DIMINISH DURING THE EVENING. MAINLY VFR DURING THE EVENING WILL
GIVE WAY TO INCREASING AMOUNTS OF IFR IN LOW STRATUS OVERNIGHT WITH
EXTENSIVE LOW LEVEL MOISTURE FIELDS. EXPECT STRATUS TO FORM FIRST
ACROSS HIGHER TERRAIN...BUT MAY SPREAD TO THE LOWER ELEVATIONS OF
WESTERN NY AS WELL AFTER ABOUT 09Z. AREAS OF FOG AND IFR VSBY ARE
LIKELY ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER AND FINGER
LAKES AS WELL WHERE THE LOW STRATUS INTERSECTS THE HILLS.
OUTLOOK...
MONDAY...VFR/MVFR IN SCATTERED SHOWERS AND THUNDERSTORMS.
TUESDAY...SHOWERS AND THUNDERSTORMS LIKELY WITH ASSOCIATED BRIEF
MVFR/IFR. SOME STORMS MAY BE STRONG.
WEDNESDAY AND THURSDAY...VFR.
&&
.MARINE...
MODERATE SOUTHERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL CRAFT
ADVISORY CONDITIONS AT THE NORTHEAST END OF LAKE ONTARIO FROM GALLOO
ISLAND TO CAPE VINCENT THROUGH EARLY AFTERNOON BEFORE
DIMINISHING. LOW PRESSURE WILL MOVE ACROSS SOUTHERN QUEBEC TODAY
WITH WINDS BECOMING MORE SOUTHWEST ON THE LOWER LAKES. EXPECT
WINDS TO INCREASE ABRUPTLY ON LAKE ERIE THROUGH EARLY
AFTERNOON...WITH A 3 TO 6 HOUR PERIOD OF 15 TO 20 KNOT WINDS AND 3
TO 5 FOOT WAVES AS WINDS ALOFT SHIFT TO THE WSW AND MIX DOWN
AS THEY ENCOUNTER THE CHAUTAUQUA RIDGE. ALSO...THERE IS A
CONVERGENCE BOUNDARY ON LAKE ERIE WHICH HAS THE POTENTIAL TO
PRODUCE WATER SPOUTS THROUGH EARLY AFTERNOON. THIS POTENTIAL WILL
END AS THE BOUNDARY SLIDES FURTHER SOUTH AND OFF THE LAKE.
THE PRESSURE GRADIENT RELAXES ACROSS THE LOWER LAKES TONIGHT AS LOW
PRESSURE DISSIPATES OVER SOUTHEAST QUEBEC. THIS WILL ALLOW WINDS AND
WAVES TO SUBSIDE.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON
FOR LOZ045.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...APFFEL/HITCHCOCK
SHORT TERM...JM
LONG TERM...JM/WCH
AVIATION...APFFEL/HITCHCOCK
MARINE...APFFEL/HITCHCOCK
AREA FORECAST DISCUSSION
NWS BUFFALO NY
751 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A SLOW MOVING TROUGH OF LOW PRESSURE WILL PRODUCE OCCASIONAL SHOWERS
AND SCATTERED THUNDERSTORMS ACROSS MUCH OF THE REGION THIS MORNING
BEFORE SLOWLY TAPERING OFF FROM NORTHWEST TO SOUTHEAST THIS
AFTERNOON. IT WILL REMAIN MUGGY ALTHOUGH EXTENSIVE CLOUD COVER WILL
KEEP TEMPERATURES LOWER THAN YESTERDAY. A FEW SPOTTY SHOWERS AND
THUNDERSTORMS ARE POSSIBLE ON LABOR DAY...BUT THE MAJORITY OF THE
DAY SHOULD BE RAIN FREE WITH TEMPERATURES WARMING BACK TO A LITTLE
ABOVE AVERAGE.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IMAGERY THIS MORNING SHOWING A SOLID AREA OF LIGHT RAIN
COVERING MUCH OF THE REGION...WITH A FEW POCKETS OF MODERATE RAIN
ACROSS THE SOUTHERN TIER AND CENTRAL NY. THE WIDESPREAD NATURE OF
THE RAIN IS LIKELY DUE TO MID LEVEL DEFORMATION AND FRONTOGENESIS
FROM A WEAK BAROCLINIC LEAF NOTED IN IR SATELLITE IMAGERY. THIS
STEADY RAIN WILL SHIFT SLOWLY EAST THROUGH THE REGION THROUGH
MIDDAY. THE BACK EDGE IS NEAR KERI-KBUF AT 1130Z...AND MUCH OF THE
NIAGARA FRONTIER WILL MISS OUT ON THE STEADIER RAIN. THAT SAID...
THE BACK EDGE MAY NOT STAY CLEAN WITH MESOSCALE MODEL GUIDANCE SUCH
AS THE HRRR SUGGESTING CONVECTIVE SHOWERS WILL DEVELOP BY LATE
MORNING ACROSS THE NIAGARA FRONTIER JUST WEST OF THE STEADIER RAIN.
FOR TODAY A MID LEVEL TROUGH WILL ADVANCE EAST ACROSS THE CENTRAL
GREAT LAKES...WITH DOWNSTREAM HEIGHT FALLS AND DPVA PRODUCED BY
CONVECTIVELY AUGMENTED VORTICITY MAXIMA AIDING IN LARGE SCALE
ASCENT. UPPER LEVEL DIVERGENCE WILL BE ENHANCED BY THE RIGHT
ENTRANCE REGION OF A 80+ KNOT UPPER LEVEL JET STRETCHING FROM LOWER
MICHIGAN TO SOUTHERN QUEBEC. A BELT OF 30-35 KNOT FLOW IN THE
900-700MB LAYER WILL AID IN ORGANIZING CONVERGENCE AND MOISTURE
TRANSPORT. AT THE SURFACE WEAK/ELONGATED LOW PRESSURE WILL MOVE INTO
SOUTHERN QUEBEC WITH A WEAK PRE-FRONTAL TROUGH EASING ACROSS THE
LOWER LAKES PROVIDING LOW LEVEL CONVERGENCE. IR SATELLITE IMAGERY
SHOWING A WEAK BAROCLINIC LEAF DEVELOPING ACROSS THE OHIO VALLEY
EARLY THIS MORNING. AS THIS FEATURE TRANSLATES NORTHEAST TODAY IT
WILL ACT TO ENHANCE MID LEVEL FRONTOGENESIS AND DEFORMATION ACROSS
OUR REGION...AIDING IN MORE WIDESPREAD SHOWERS. PWAT VALUES ARE
AROUND 1.8 INCHES ON AVERAGE WITH AMPLE MOISTURE IN PLACE.
GIVEN THE QUALITY MOISTURE AND SUFFICIENT FORCING FOR ASCENT COMING
TOGETHER...HAVE RAISED POPS TO CATEGORICAL FOR THE BULK OF THE AREA
THIS MORNING WITH THE EXCEPTION OF A FEW COUNTIES ALONG THE CANADIAN
BORDER WHERE SHOWERS SHOULD BE A LITTLE LESS FREQUENT. IN GENERAL
THE MOST PERSISTENT RAIN AND HIGHEST AMOUNTS SHOULD FOCUS FROM THE
WESTERN SOUTHERN TIER TO THE FINGER LAKES AND SOUTHERN TUG HILL
REGION WITH LESSER AMOUNTS NEAR THE INTERNATIONAL BORDER. ENOUGH
INSTABILITY WILL REMAIN TO KEEP A FEW EMBEDDED THUNDERSTORMS AS
WELL...ALTHOUGH COVERAGE WILL REMAIN WIDELY SCATTERED. A FEW STORMS
MAY PRODUCE LOCALLY HEAVY RAINFALL...BUT THIS RISK SHOULD REMAIN
VERY ISOLATED AT BEST.
THIS AFTERNOON THE AFOREMENTIONED DYNAMICS AND BAROCLINIC LEAF WILL
SHIFT SLOWLY SOUTH AND EAST AND TAKE THE STEADIER SHOWERS WITH IT.
EXPECT A DRYING TREND FOR THE AFTERNOON FROM NORTHWEST TO SOUTHEAST
WITH AREAS ALONG AND NORTH OF THE NYS THRUWAY EVENTUALLY BECOMING
MAINLY DRY WITH A FEW BREAKS OF SUNSHINE POSSIBLE LATE. SHOWERS WILL
BE SLOWER TO END ACROSS THE SOUTHERN TIER AND ACROSS THE HIGHER
TERRAIN EAST OF LAKE ONTARIO.
THE EXTENSIVE CLOUD COVER WILL KEEP TEMPERATURES LOWER TODAY
ALTHOUGH IT WILL STILL BE VERY MUGGY. EXPECT HIGHS IN THE UPPER 70S
ON THE LAKE PLAINS AND LOWER TO MID 70S ACROSS THE HIGHER TERRAIN.
THE WARM SPOT SHOULD BE THE SAINT LAWRENCE VALLEY WHERE SHOWERS AND
THICKER CLOUD COVER WILL EXIT THE EARLIEST.
TONIGHT SHOWERS ACROSS THE SOUTHERN TIER AND CENTRAL NY WILL
CONTINUE TO SLOWLY DIMINISH. ENOUGH INSTABILITY MAY DEVELOP IN THE
WAKE OF THIS MAIN RAIN AREA TO ALLOW SCATTERED THUNDERSTORMS TO FORM
DURING THE LATE AFTERNOON AND EARLY EVENING ACROSS THE NIAGARA
PENINSULA. IF THEY MATERIALIZE...A FEW MAY MAKE IT INTO AREAS JUST
NORTH OF BUFFALO THIS EVENING. SCATTERED STORMS MAY ALSO FORM OVER
SOUTHEAST ONTARIO AND CROSS THE SAINT LAWRENCE INTO THE NORTH
COUNTRY THIS EVENING. OTHERWISE EXPECT SOME PARTIAL CLEARING
OVERNIGHT ON THE LAKE PLAINS. ACROSS THE HIGHER TERRAIN LOW LEVEL
MOISTURE AND WEAK UPSLOPE FLOW AND CONVERGENCE WILL LIKELY SUPPORT
EXPANDING LOW CLOUD COVER. EXPECT LOWS IN THE MID TO UPPER 60S ON
THE LAKE PLAINS AND LOWER TO MID 60S IN THE SOUTHERN TIER AND NORTH
COUNTRY.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A WARM AND STICKY AIRMASS WILL REMAIN ACROSS THE REGION ON
MONDAY...WITH MOST OF THE FORECAST AREA EXPERIENCING MAINLY DRY
CONDITIONS. HOWEVER THERE WILL BE THE CHANCE FOR SCATTERED SHOWERS
AND THUNDERSTORMS IN THE AFTERNOON AND EVENING...MAINLY ACROSS THE
INTERIOR SOUTHERN TIER WHERE THE BEST INSTABILITY WILL RESIDE. CAPE
VALUES BY LATER IN THE AFTERNOON ACROSS THIS REGION WILL RUN IN THE
1000-1500 J/KG RANGE WITH LI`S POSSIBLY AS LOW AS -4. HOWEVER WITH
WEAK 0-6KM BULK SHEAR (~20KTS) AND LACK OF A GOOD SURFACE TRIGGER
(ASIDE FROM A POSSIBLE LAKE BREEZE)...NOT EXPECTING ANY
THUNDERSTORMS TO REACH SEVERE LIMITS. INSTABILITY LOOKS LOWER ACROSS
THE REMAINDER OF THE AREA...AND THUS CONVECTIVE CHANCES LOOK MUCH
LOWER AS WELL. TEMPERATURES WILL AGAIN BE ON THE WARM SIDE WITH
HIGHS IN THE UPPER 70S TO LOWER 80S.
WITH THE LOSS OF DAYTIME HEATING MONDAY NIGHT MOST OF THE DIURNALLY
DRIVEN CONVECTION WILL DIMINISH IN COVERAGE...ALTHOUGH A FEW STORMS
MAY CONTINUE LATE INTO THE EVENING...ESPECIALLY ACROSS PORTIONS OF
THE SOUTHERN TIER. AT THE SAME TIME A COLD FRONT OVER THE UPPER
GREAT LAKES WILL BE ADVANCING TOWARD THE REGION AND BE LOCATED WEST
OF NEW YORK STATE BY TUESDAY MORNING. THAT SAID...MOST OF THE NIGHT
LOOKS TO REMAIN DRY...WITH PRECIP CHANCES STARTING TO INCREASE A BIT
ACROSS WESTERN NEW YORK TOWARD TUESDAY MORNING. ANOTHER MILD
NIGHT CAN BE EXPECTED WITH LOWS IN THE MID TO UPPER 60S FOR MOST
LOCATIONS THANKS TO DEEP SOUTHERLY FLOW OUT AHEAD OF THE APPROACHING
COLD FRONT.
LATEST GUIDANCE PACKAGE HAS THE COLD FRONT NOW MOVING A BIT SLOWER
THAN IN PREVIOUS RUNS. THIS IS MOST LIKELY DUE TO MOST OF THE MODELS
NOW COMING INTO AGREEMENT ON THE DEVELOPMENT OF LOW PRESSURE
SOMEWHERE IN THE OHIO VALLEY ALONG THE FRONT AND THEN TRACKING IT
NORTHEAST ALONG THE BOUNDARY WHICH WOULD SLOW IT DOWN A LITTLE.
THAT SAID...IT NOW APPEARS IT WILL TAKE THE BULK OF THE DAY TUESDAY
FOR THE COLD FRONT TO SWEEP ACROSS THE REGION WITH SHOWERS AN
THUNDERSTORMS LIKELY...WITH LOWER CHANCE POPS BY LATER IN THE DAY
ACROSS WESTERN NEW YORK. HIGH PRECIPITABLE WATER VALUES OF 1.7"-1.9"
TUESDAY AFTERNOON OFFER THE RISK OF HEAVY DOWNPOURS WITH ANY
THUNDERSTORM. SBCAPES OVER 1000 J/KG COMBINED WITH LIFTED INDEX
VALUES AT -4C TO -5C ALSO POINT TO THE POSSIBILITY OF STORMS. THE
MAIN DIFFERENCES FROM MONDAY ARE THAT 0-6KM BULK SHEAR VALUES LOOK
TO BE IN THE 40-45KT RANGE...AND ALSO HAVE THE SURFACE COLD FRONT
CROSSING THE FORECAST AREA WHICH WILL SERVE AS THE FOCAL POINT FOR
STORMS TO FIRE ALONG. ALL THIS SAID...LOOKS AS THOUGH THERE COULD BE
SOME STRONG STORMS...WITH A FEW STORMS POSSIBLY REACHING SEVERE
LIMITS. MAIN THREATS APPEAR TO BE GUSTY WINDS ASSOCIATED WITH BOWING
LINE SEGMENTS AND MARGINALLY SEVERE HAIL. ANOTHER WARM DAY ON TAP
WITH HIGHS IN THE UPPER 70S TO LOWER 80S.
THE COLD FRONT WILL SLIDE SOUTH AND EAST OF THE FORECAST AREA
TUESDAY EVENING...TAKING THE SHOWERS AND STORMS WITH IT. ALTHOUGH A
FEW SHOWERS WILL STILL BE POSSIBLE DURING THE EVENING ACROSS EASTERN
AREAS...BUT EVEN HERE THINGS WILL DRY OUT LATER TUESDAY NIGHT AS
SURFACE HIGH PRESSURE STARTS TO BUILD EAST ACROSS NEW YORK STATE.
LOWS WILL BE GENERALLY IN THE UPPER 50S TO LOWER 60S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE WILL BUILD ACROSS THE
REGION WEDNESDAY AND THURSDAY BRINGING IN DRIER AIR AND TEMPERATURES
THAT WILL STILL AVERAGE AT OR JUST A BIT ABOVE NORMAL FOR EARLY
SEPTEMBER. HIGH PRESSURE WILL THEN SLIDE OFF THE NEW ENGLAND COAST
BY FRIDAY. THIS WILL PROVIDE MAINLY DRY CONDITIONS THROUGH
MIDWEEK...BEFORE THE NEXT FRONTAL SYSTEM APPROACHES FOR LATE IN THE
WEEK AND EARLY WEEKEND. TEMPERATURES WILL BE A BIT ABOVE SEASONAL
NORMALS WITH HIGHS IN THE UPPER 70S TO LOW 80S AND LOWS IN THE LOWER
60S.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A STEADY AREA OF LIGHT RAIN WILL CONTINUE TO MOVE SLOWLY EAST ACROSS
THE SOUTHERN TIER...FINGER LAKES...AND CENTRAL NY THROUGH MIDDAY.
CIGS/VSBY WILL REMAIN VFR IN MANY AREAS...ALTHOUGH A FEW POCKETS OF
MODERATE RAIN WILL PRODUCE MVFR VSBY AT TIMES. EXPECT POCKETS OF
MVFR/IFR CIGS TO ALSO BECOME A LITTLE MORE COMMON BY MID MORNING
ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER AND FINGER LAKES. THE
LOWER ELEVATIONS ON THE LAKE PLAINS SHOULD STAY MAINLY VFR DUE IN
PART TO SSW DOWNSLOPE FLOW.
THE STEADIER SHOWERS WILL DIMINISH FROM NORTHWEST TO SOUTHEAST
DURING THE LATE MORNING TO EARLY AFTERNOON. EXPECT CIGS/VSBY TO
IMPROVE TO MAINLY VFR EXCEPT IN ANY HEAVIER SHOWERS AND WIDELY
SCATTERED THUNDERSTORMS THAT DEVELOP WITH DAYTIME HEATING THIS
AFTERNOON. BY MID AFTERNOON THESE SHOULD BE CONFINED TO THE SOUTHERN
TIER AND CENTRAL NY WITH THE REMAINDER OF THE AREA DRY.
TONIGHT ANY SHOWERS AND SCATTERED THUNDER ACROSS THE SOUTHERN TIER
WILL DIMINISH DURING THE EVENING. MAINLY VFR DURING THE EVENING WILL
GIVE WAY TO INCREASING AMOUNTS OF IFR IN LOW STRATUS OVERNIGHT WITH
EXTENSIVE LOW LEVEL MOISTURE FIELDS. EXPECT STRATUS TO FORM FIRST
ACROSS HIGHER TERRAIN...BUT MAY SPREAD TO THE LOWER ELEVATIONS OF
WESTERN NY AS WELL AFTER ABOUT 09Z. AREAS OF FOG AND IFR VSBY ARE
LIKELY ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER AND FINGER
LAKES AS WELL WHERE THE LOW STRATUS INTERSECTS THE HILLS.
OUTLOOK...
MONDAY...VFR/MVFR IN SCATTERED SHOWERS AND THUNDERSTORMS.
TUESDAY...SHOWERS AND THUNDERSTORMS LIKELY WITH ASSOCIATED BRIEF
MVFR/IFR. SOME STORMS MAY BE STRONG.
WEDNESDAY AND THURSDAY...VFR.
&&
.MARINE...
MODERATE SOUTHERLIES WILL CONTINUE TO PRODUCE MARGINAL SMALL CRAFT
ADVISORY CONDITIONS AT THE NORTHEAST END OF LAKE ONTARIO FROM GALLOO
ISLAND TO CAPE VINCENT THROUGH EARLY TO MID MORNING BEFORE
DIMINISHING. LOW PRESSURE WILL MOVE ACROSS SOUTHERN QUEBEC TODAY
WITH WINDS BECOMING MORE SOUTHWEST ON THE LOWER LAKES. THIS WILL
ALLOW WINDS TO INCREASE SOMEWHAT ON LAKE ERIE...WITH MARGINAL SMALL
CRAFT ADVISORY CONDITIONS FROM MID TO LATE MORNING THROUGH MID TO
LATE AFTERNOON.
THE PRESSURE GRADIENT RELAXES ACROSS THE LOWER LAKES TONIGHT AS LOW
PRESSURE DISSIPATES OVER SOUTHEAST QUEBEC. THIS WILL ALLOW WINDS AND
WAVES TO SUBSIDE.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR
LOZ045.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...JM
LONG TERM...JM/WCH
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS RALEIGH NC
813 PM EDT MON SEP 1 2014
.SYNOPSIS...AN AREA OF HIGH PRESSURE WILL EXTEND OVER THE REGION
THROUGH TUESDAY. A WEAK SURFACE FRONT WILL SETTLE SOUTHWARD ACROSS
CENTRAL NC ON WEDNESDAY. HIGH PRESSURE WILL BUILD BACK OVER THE AREA
FOR THE REMAINDER OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 305 PM MONDAY...
LATE THIS AFTERNOON THROUGH TONIGHT... SLIGHT TO MODERATELY UNSTABLE
COVERS CENTRAL NC AT MID AFTERNOON WITH A WEAK SHEAR AXIS SLOWLY
EDGING EASTWARD ACROSS THE REGION. BEST DYNAMICS/LIFT ASSOCIATED
WITH THIS FEATURE WELL NORTH OF OUR REGION AS SHEAR AXIS IS IMPEDING
UPON A MID-UPPER LEVEL RIDGE POSITIONED OVER EASTERN NC. THE RIDGE
WILL CONTINUE TO INHIBIT MOST CONVECTIVE DEVELOPMENT BUT COULD STILL
SEE AN ISOLATED STORM OR TWO DEVELOP ACROSS THE REGION. BASED ON 18Z
MESO-ANALYSIS...ISOLATED CONVECTIVE DEVELOPMENT APPEARS TO BE
FAVORED OVER THE WESTERN PIEDMONT...AND NEAR THE VIRGINIA BORDER
COUNTIES. THIS SCENARIO HAS THE SUPPORT OF THE LATEST HRRR (WHICH
HAS BEEN TRENDING WETTER). THE CONVECTIVE ALLOWING
MODELS...THOUGH...HAVE BEEN TRENDING DRIER AND NOW SUGGEST THAT
ISOLATED CONVECTION WILL OCCUR OUTSIDE OF OUR FORECAST AREA.
WILL LIKELY SEE PATCHES OF FOG DEVELOP AFTER MIDNIGHT...MAINLY OVER
THE COASTAL PLAIN..SANDHILLS AND EASTERN PIEDMONT. HOWEVER DENSE FOG
WILL BE RARE WITH BULK OF THE VISIBILITIES AT OR ABOVE 1-2 MILES.
MIN TEMPS OVERNIGHT NEAR 70-LOWER 70S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 305 PM MONDAY...
TUESDAY AND TUESDAY NIGHT... MID-UPPER LEVEL RIDGE PROJECTED TO
SLOWLY WEAKEN THIS PERIOD. THIS MAY ALLOW A FEW MORE T-STORMS TO
DEVELOP IN THE SLIGHT-MODERATELY UNSTABLE AIR MASS TUESDAY AFTERNOON-
EVENING. IN ADDITION...A S/W RESPONSIBLE FOR TRIGGERING THE
CONVECTION ACROSS PARTS OF THE MISSOURI VALLEY/OZARKS THIS AFTERNOON-
EVENING WILL APPROACH CENTRAL NC FROM THE NW LATE IN THE DAY. THIS
FEATURE MAY TRIGGER ADDITIONAL ISOLATED-SCATTERED CONVECTION TUESDAY
EVENING ACROSS THE NW PIEDMONT...AND OVERNIGHT TUESDAY INTO EARLY
WEDNESDAY OVER THE REMAINDER OF CENTRAL NC. WHILE FORCING IS BETTER
COMPARED TO THE PAST FEW DAYS...LIFT IS STILL CONSIDERED WEAK-
MARGINAL AT BEST. THUS WILL LIMIT POPS TO NO HIGHER THAN LOW CHANCE.
ANOTHER HOT DAY IN STORE FOR THE REGION. AFTERNOON THICKNESSES WILL
REMAIN 20-25M ABOVE NORMAL...SUPPORTIVE OF HIGH TEMPS IN THE LOW-MID
90S UNDER FULL SUN CONDITIONS. WHEN THE HUMIDITY IS FACTORED
IN...HEAT INDEX VALUES NEAR 100-104 WILL BE COMMON WITH THE HIGHEST
H.I.VALUES IN THE SOUTHERN COASTAL PLAIN AND SANDHILLS. MIN TEMPS
TUESDAY NIGHT GENERALLY IN THE LOWER 70S. -WSS
FOR WED/WED NIGHT: THE WEAK SURFACE REFLECTION THAT REMAINS FROM THE
COLD FRONT APPROACHING CENTRAL NC WILL BECOME EVEN MORE WASHED OUT
AS IT SHIFTS INTO THE LEE TROUGH OVER CENTRAL NC. MODELS SHOW A VERY
WEAK VORTICITY LOBE ASSOCIATED WITH THIS FRONT PUSHING ESE THROUGH
NC EARLY WED... AND ITS APPROACH ALONG WITH LINGERING STRONG LOW
LEVEL MOISTURE TRANSPORT OVER ERN NC SHOULD SUPPORT AN AREA OF
ATYPICAL MORNING SHOWERS/STORMS OVER THE ERN AND ESPECIALLY SE CWA
WED MORNING. THE DEPARTURE AND DAMPENING OF THE MEAN MID LEVEL
TROUGH WELL TO OUR NE WILL RESULT IN MODEST RISING HEIGHTS (15-25 M)
WITHIN THE FLAT (W-E ORIENTED) MID LEVEL RIDGE ACROSS NC THROUGH WED
NIGHT. THE LATEST NAM RUN IS CONSISTENT WITH PREVIOUS RUNS IN
BRINGING LOWER PW (UNDER 1.5") INTO MUCH OF THE CWA FROM THE NW WITH
A BIT STRONGER 850-700 MB NW WIND AS COMPARED TO THE GFS... WHICH
KEEPS PW VALUES UP TO 1.7-1.9". GIVEN THE FACT THAT THE MID LEVEL
TROUGH WILL BE DAMPENING WITH LITTLE REASON TO SUPPORT A STRONG PUSH
OF DRY AIR PAST THE MOUNTAINS... THE GFS`S MORE SUBDUED TROUGH
INFLUENCE APPEARS MORE LIKELY... BASED ON THE PERSISTENCE OF THE
STRONG RIDGE. MODERATE INSTABILITY IS EXPECTED OVER ALL BUT PERHAPS
THE FAR NW... WITH THE GFS SHOWING MUCAPE PEAKING AT 1000-2500 J/KG.
WILL STAY CLOSE TO THE GFS/ECMWF SOLUTION WITH SCATTERED AFTERNOON
THROUGH EVENING STORMS... WITH BEST COVERAGE ACROSS THE SOUTHERN CWA
AND ALONG/EAST OF THE PERSISTENT LEE TROUGH... AS WELL AS ALONG THE
INLAND-TRACKING SEA BREEZE. WITH ABOVE-NORMAL PW AND WEAK MID LEVEL
FLOW... SLOW-MOVERS AND HEAVY-RAINERS ARE POSSIBLE. WITH THICKNESSES
A TAD LOWER THAN TUE BUT REMAINING 12-20 M ABOVE NORMAL... EXPECT
WARM AND STICKY HIGHS OF 91-95... DESPITE A GOOD CHANCE OF DEBRIS
CLOUD COVER THROUGH THE DAY. CONVECTION CHANCES SHOULD RECEDE WED
NIGHT BUT THE GFS INDICATES PLENTY OF ELEVATED BUOYANCY POTENTIAL
OVERNIGHT... INCLUDING MLCAPE OF 500-1000 J/KG RESULTING FROM VERY
WARM 960-920 MB TEMPS. WILL HOLD ONTO CHANCE POPS MAINLY SOUTH HALF
OVERNIGHT. MUGGY LOWS IN THE LOW-MID 70S. -GIH
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 230 PM MONDAY...
FOR THU/FRI: CONTINUED ABOVE-NORMAL WARMTH WITH ONLY MINOR CHANGES
IN AIR MASS. AT THE SURFACE... THE WEAK LEE TROUGH HOLDS THROUGH
CENTRAL NC... ALONG WITH A HUMID AND SOMEWHAT STAGNANT AIR MASS. A
POSITIVELY TILTED TROUGH SHIFTS THROUGH THE PACIFIC NORTHWEST AND SW
CANADA INTO THE DAKOTAS THU... RESULTING IN BUILDING HEIGHTS AND
GRADUAL MID LEVEL WARMING OVER THE SOUTHEAST STATES. THIS POLAR
STREAM TROUGH THEN SHIFTS INTO ERN CANADA... WHILE THE FLAT RIDGE
HOLDS ACROSS NC. WITH PLENTY OF LOW LEVEL MOISTURE POOLING...
ISOLATED TO SCATTERED STORMS FOCUSED ALONG A SEA BREEZE OR SOME
OTHER SUBTLE BOUNDARY REMAIN A GOOD BET... DESPITE THE WARMING TEMPS
ALOFT. WILL RETAIN AFTERNOON AND EVENING STORM CHANCES BOTH DAYS...
WITH TEMPS HOLDING ABOUT A CATEGORY ABOVE NORMAL AS THICKNESSES STAY
10-15 M ABOVE NORMAL.
FOR SAT THROUGH MON: A PATTERN TRANSITION IS LIKELY NEXT WEEKEND.
THE INITIAL MID LEVEL TROUGH CONTINUES HEADING EASTWARD OVER ERN
CANADA EARLY SAT... HOWEVER A SLUG OF STRONG VORTICITY EMANATING
FROM A STRONG COLD VORTEX OVER THE BEAUFORT SEA WILL PUSH EASTWARD
CLOSE ON ITS HEELS... TAKING A COLD FRONT TO NEW ENGLAND AND THE OH
VALLEY BY EARLY SAT. THE RESULTING TROUGH OVER ERN NOAM SUNDAY
SHOULD HELP PUSH THE FRONT SOUTHWARD INTO NC... AFTER WHICH TIME IT
IS APT TO LAY WEST/EAST AND STALL OVER THE CAROLINAS FOR LATE SUN
THROUGH MON. THE GFS HAS A STRONGER/FASTER TIME FRAME THAN THE
ECMWF... WITH THE FORMER MODEL SOLUTION TAKING THICKNESSES MUCH
COLDER... UP TO 25 M BELOW NORMAL AS OPPOSED TO THE ECMWF WHICH IS
BARELY 5 M BELOW NORMAL. TOUGH TO RESOLVE SUCH DIFFERENCES BUT GIVEN
THE STRENGTH OF THE SRN CONUS RIDGE... AND THE FAR-NORTH TRACK OF
THE POLAR LOW... I REMAIN SKEPTICAL ABOUT A STRONG COLD FRONTAL
PASSAGE THROUGH NC. WILL STAY ON THE CONSERVATIVE SIDE OF THE TEMP
TREND... WITH HIGHS/LOWS INITIALLY AROUND 90/AROUND 70 SAT...
SLIPPING TO LOW-MID 80S/UPPER 60S BY MON. PRECIP CHANCES AND
PATTERNS ARE LIKELY TO CHANGE LITTLE THROUGH SUN... PERHAPS
INCREASING IN COVERAGE AS THE FRONT APPROACHES WITH FALLING HEIGHTS
ALOFT... STRENGTHENING (YET STILL SOMEWHAT WEAK) MID LEVEL FLOW...
AND A PERSISTENT CONFLUENT INFLUX OF GULF AND ATLANTIC MOISTURE IN
THE LOW LEVELS. WILL MAINTAIN SCATTERED SHOWERS AND STORMS FOCUSED
ON -- BUT NOT RESTRICTED TO -- AFTERNOON AND EVENING HOURS. WILL
KEEP A CLIMO CHANCE POP ON MON... WITH LOWER THAN USUAL CONFIDENCE
AS CONVECTION WILL GREATLY DEPEND ON WHETHER THE FRONT HOLDS UP
ACROSS NC OR SHIFTS TO OUR SOUTH. -GIH
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 800 PM MONDAY...
MOSTLY VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGHOUT THE CURRENT
TAF PERIOD. THE EXCEPTION WILL A BRIEF PERIOD OF LOW STRATUS/FOG
TOWARDS DAYBREAK ON TUESDAY...MOST LIKELY ACROSS THE EASTERN HALF OF
THE FORECAST AREA AND WITH KRWI HAVING THE HIGHEST PROBABILITY (GIVEN
THE PERSISTENT AIR MASS IN PLACE). AFTER ALMOST CALM WINDS
OVERNIGHT...MOSTLY LIGHT (UNDER 10 KNOTS) SOUTHWESTERLY WINDS WILL
PREVAIL. ISOLATED STORMS ARE EXPECTED TUESDAY AFTERNOON/EVENING.
OUTLOOK...TYPICAL SUMMERTIME CONDITIONS ARE EXPECTED TO PERSIST
THROUGH THE PERIOD...FEATURING DIURNAL CONVECTION EACH
AFTERNOON/EVENING AND PATCHY FOG/LOW CLOUDS DURING THE PRE-DAWN
MORNING HOURS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...KRD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
729 AM EDT SUN AUG 31 2014
.SYNOPSIS...
STRENGTHENING BERMUDA HIGH PRESSURE OFFSHORE WILL BRING SUMMERTIME
HEAT AND HUMIDITY THROUGH THE LABOR DAY WEEKEND WITH A FEW SHOWERS
AND THUNDERSTORMS POSSIBLE. A WEAK COLD FRONT WILL APPROACH FROM THE
NORTH LATE NEXT WEEK...BUT WILL LIKELY STALL BEFORE REACHING THE
AREA. BERMUDA HIGH PRESSURE AND A PIEDMONT TROUGH WILL REMAIN THE
DOMINANT FEATURES INTO NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SUNDAY...SURFACE HIGH PRESSURE COVERS MUCH OF THE
WESTERN AND CENTRAL ATLANTIC OCEAN. THE UPPER LEVEL RIDGE IS
CENTERED JUST OFF THE CAROLINA COAST AND SHOULD KEEP ANY SYNOPTIC
IMPULSES DEFLECTED AWAY TO OUR NORTH AND WEST. 850 MB TEMPERATURES
AROUND +18C THIS AFTERNOON SHOULD RESULT IN HIGH TEMPERATURES IN THE
MID 90S FROM MARION AND FLORENCE WESTWARD INTO DARLINGTON COUNTY.
ONSHORE WINDS CLOSER TO THE COAST SHOULD KEEP TEMPERATURES A LITTLE
COOLER...GENERALLY IN THE UPPER 80S TO LOWER 90S.
ALTHOUGH THERE IS CONSIDERABLE DRY AIR ALOFT DUE TO THE UPPER RIDGE
(COLUMN PRECIP WATER VALUES ARE ONLY 1.5 INCHES) VERY RICH MOISTURE
EXISTS IN THE LOWEST LEVELS OF THE ATMOSPHERE. DEWPOINTS IN THE MID
70S THIS MORNING WILL FORTUNATELY MIX DOWN TO NEAR 70 THIS AFTERNOON
INLAND...BUT THAT WILL STILL BE ENOUGH TO PUSH HEAT INDICES TO
100-103 DEGREES ACROSS MOST OF OUR FORECAST AREA. THIS MOISTURE MAY
ALSO FUEL WIDELY SCATTERED SHOWERS NEAR THIS COAST LATER THIS
MORNING...PROBABLY BECOMING LESSER IN COVERAGE THIS AFTERNOON AS
DRIER AIR MIXES DOWNWARD. FORECAST POPS RANGE FROM 20-30 PERCENT...
VIRTUALLY ALL EAST OF I-95 AND HIGHEST IN A STRIPE ACROSS LELAND TO
BURGAW AS CONSISTENTLY INDICATED BY HOURLY HRRR MODEL RUNS THROUGH
THE NIGHT.
ANY LINGERING DAYTIME CUMULUS SHOULD QUICKLY DIE AWAY THIS
EVENING... WITH ONLY A LITTLE PATCHY FOG OR LOW STRATUS EXPECTED TO
DEVELOP OVERNIGHT. LOWS SHOULD FALL INTO THE LOWER 70S FOR MOST
LOCALES...A FEW DEGREES WARMER NEAR THE BEACHES.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND STRENGTHENING PIEDMONT TROUGH
WILL BE THE MAIN SURFACE FEATURES THROUGH THE PERIOD. ALOFT A FLAT
MID LEVEL RIDGE WILL EXTEND ACROSS MUCH OF THE SOUTHERN CONUS. DEEP
WESTERLY FLOW IN THE MID LEVELS WILL PUSH TROPICAL MOISTURE
EXPANDING NORTH FROM THE WESTERN GULF OF MEXICO OVER THE REGION MON
AND TUE. INCREASING MOISTURE ALOFT ALONG WITH LOW LEVEL MOISTURE
ADVECTION AROUND WEST SIDE OF BERMUDA HIGH WILL PUSH PRECIPITABLE
WATER VALUES OVER 2 INCHES FOR MUCH OF THE PERIOD.
FLAT MID LEVEL PATTERN MEANS LITTLE TO NO FORCING ALOFT WILL BE
PRESENT. HOWEVER THE COMBINATION OF LOW LEVEL MOISTURE AND SURFACE
HEATING WILL PUSH ML CAPE VALUES TO 1K-2K J/KG FOR MON AND OVER 2K
J/KG ON TUE. CONVECTION WILL INITIALLY BE SLOW TO DEVELOP BUT ONCE
SEA BREEZE AND PIEDMONT TROUGH TAKE SHAPE SHOWERS AND THUNDERSTORMS
SHOULD START POPPING UP. WILL MAINTAIN CHC POP FOR EACH AFTERNOON
BUT WITH SLIGHTLY HIGHER VALUES ON TUE GIVEN SLIGHTLY HIGHER CAPE
VALUES.
TEMPERATURES WILL RUN ABOVE CLIMO THROUGH THE PERIOD. HIGHS WILL
RANGE FROM UPPER 80S ALONG THE IMMEDIATE COAST TO MID 90S INLAND.
LOWS WILL BE IN THE LOW TO MID 70S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND PIEDMONT TROUGH ALONG WITH
ELONGATED MID LEVEL RIDGE WILL REMAIN THE SIGNIFICANT FEATURES
THROUGH THE PERIOD. A COUPLE COLD FRONTS WILL TRY AND MAKE A RUN TO
THE AREA DURING THE NEXT WEEK BUT THEY ARE LIKELY TO STALL AND WASH
OUT JUST NORTH OF THE FORECAST AREA. THE SURFACE AND MID LEVEL
PATTERNS ARE NOT ONES THAT GENERALLY SUPPORT FRONTS MOVING INTO AND
SOUTH OF THE CAPE FEAR REGION. PRECIPITABLE WATER VALUES WILL REMAIN
AROUND 2 INCHES THROUGH THE END OF THE WEEK. DIURNAL HEATING AND
SOUTHWEST FLOW WILL RESULT IN ML CAPE VALUES ABOVE 2K J/KG FOR MUCH
OF THE PERIOD. WEAK GRADIENT WILL ALLOW SEA BREEZE DEVELOPMENT AND
PIEDMONT TROUGH SHOULD BE WELL DEFINED. TYPICAL SUMMER PATTERN WITH
NEAR CLIMO PWATS AND TEMPERATURES NEAR TO SLIGHTLY ABOVE CLIMO
SUGGEST POP WILL BE NEAR CLIMO FOR MUCH OF THE PERIOD...30 PERCENT.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 12Z...IFR TEMPO LIFR IN BR/FG OCCURRING AT KFLO THIS
MORNING. KLBT IS VFR. TEMPO MVFR CIGS ARE OCCURRING AT KCRE/KMYR.
ISOLATED LIGHT SHOWERS ARE MOVING N ACROSS THE NEAR SHORE WATERS.
BR/FG SHOULD BURN OFF AROUND 14Z AT KFLO. VFR IS THEN EXPECTED AT
BOTH KFLO/KLBT INTO THIS EVENING. TEMPO MVFR CIGS/SHOWERS WILL
REMAIN POSSIBLE AT THE COASTAL TERMINALS UNTIL THE SEA SHIFTS
FURTHER INLAND MID-LATE MORNING. BEST CONFIDENCE OF A TEMPO SHOWER
IS AT KILM. VFR IS THEN EXPECTED AFTERWARDS AT THE COASTAL
TERMINALS INTO THIS EVENING. THIS AFTERNOON THE BEST SHOWER
POTENTIAL WILL BE BETWEEN THE INLAND AND COASTAL TERMINALS. SE-S
WINDS WILL INCREASE TO 10-20 KT AT THE COASTAL TERMINALS AND 5 TO
10 KT AT KFLO/KLBT LATER THIS MORNING.
WINDS SLOWLY DECREASE THIS EVENING...BECOMING LGT S-SW THIS
EVENING AND OVERNIGHT. BEST BR/FG POTENTIAL WILL BE THE INLAND TERMINALS
OVERNIGHT...WITH IFR VSBYS/LIFR CIGS LIKELY KFLO/KLBT BY 08Z.
EXTENDED OUTLOOK...INCREASING CHANCES FOR AFTN SHOWERS/TSTMS MONDAY
THROUGH THURSDAY WITH BRIEF AND LOCALIZED PERIODS OF MVFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SUNDAY...SURFACE HIGH PRESSURE COVERS MOST OF THE
WESTERN AND CENTRAL ATLANTIC OCEAN. THIS SHOULD PRODUCE A
SOUTH-SOUTHEAST WIND TODAY...VEERING MORE SOUTHWESTERLY TONIGHT.
SEAS CURRENTLY AROUND 2 FEET MAY OCCASIONALLY REACH 3 FEET IN A
COMBINATION OF SOUTHEASTERLY SWELL AND LOCAL WIND WAVES...WITH ANY
SCATTERED MORNING SHOWERS EXPECTED TO DISSIPATE BY EARLY AFTERNOON.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND PIEDMONT TROUGH WILL MAINTAIN
SOUTHWEST FLOW OVER THE WATERS THROUGH THE PERIOD. SPEEDS 10 KT OR
LESS WILL INCREASE TO A SOLID 15 KT EACH AFTERNOON AND EVENING AS
THE PIEDMONT TROUGH STRENGTHENS. SEAS IN THE 2 TO 3 FT RANGE.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...MINIMAL CHANGE FOR THE LONG TERM PERIOD. BERMUDA
HIGH REMAINS IN PLACE AS DOES THE PIEDMONT TROUGH. LATE IN THE
PERIOD A WEAKENING COLD FRONT WILL APPROACH FROM THE NORTH BUT IS
EXPECTED TO STALL BEFORE REACHING THE AREA. SOUTHWEST FLOW AROUND 10
KT WILL INCREASE TO A SOLID 15 KT EACH AFTERNOON AND EVENING. SEAS
WILL RUN 2 TO 3 FT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...III
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
633 AM EDT SUN AUG 31 2014
.SYNOPSIS...
STRENGTHENING BERMUDA HIGH PRESSURE OFFSHORE WILL BRING SUMMERTIME
HEAT AND HUMIDITY THROUGH THE LABOR DAY WEEKEND WITH A FEW SHOWERS
AND THUNDERSTORMS POSSIBLE. A WEAK COLD FRONT WILL APPROACH FROM THE
NORTH LATE NEXT WEEK...BUT WILL LIKELY STALL BEFORE REACHING THE
AREA. BERMUDA HIGH PRESSURE AND A PIEDMONT TROUGH WILL REMAIN THE
DOMINANT FEATURES INTO NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SUNDAY...SURFACE HIGH PRESSURE COVERS MUCH OF THE
WESTERN AND CENTRAL ATLANTIC OCEAN. THE UPPER LEVEL RIDGE IS
CENTERED JUST OFF THE CAROLINA COAST AND SHOULD KEEP ANY SYNOPTIC
IMPULSES DEFLECTED AWAY TO OUR NORTH AND WEST. 850 MB TEMPERATURES
AROUND +18C THIS AFTERNOON SHOULD RESULT IN HIGH TEMPERATURES IN THE
MID 90S FROM MARION AND FLORENCE WESTWARD INTO DARLINGTON COUNTY.
ONSHORE WINDS CLOSER TO THE COAST SHOULD KEEP TEMPERATURES A LITTLE
COOLER...GENERALLY IN THE UPPER 80S TO LOWER 90S.
ALTHOUGH THERE IS CONSIDERABLE DRY AIR ALOFT DUE TO THE UPPER RIDGE
(COLUMN PRECIP WATER VALUES ARE ONLY 1.5 INCHES) VERY RICH MOISTURE
EXISTS IN THE LOWEST LEVELS OF THE ATMOSPHERE. DEWPOINTS IN THE MID
70S THIS MORNING WILL FORTUNATELY MIX DOWN TO NEAR 70 THIS AFTERNOON
INLAND...BUT THAT WILL STILL BE ENOUGH TO PUSH HEAT INDICES TO
100-103 DEGREES ACROSS MOST OF OUR FORECAST AREA. THIS MOISTURE MAY
ALSO FUEL WIDELY SCATTERED SHOWERS NEAR THIS COAST LATER THIS
MORNING...PROBABLY BECOMING LESSER IN COVERAGE THIS AFTERNOON AS
DRIER AIR MIXES DOWNWARD. FORECAST POPS RANGE FROM 20-30 PERCENT...
VIRTUALLY ALL EAST OF I-95 AND HIGHEST IN A STRIPE ACROSS LELAND TO
BURGAW AS CONSISTENTLY INDICATED BY HOURLY HRRR MODEL RUNS THROUGH
THE NIGHT.
ANY LINGERING DAYTIME CUMULUS SHOULD QUICKLY DIE AWAY THIS
EVENING... WITH ONLY A LITTLE PATCHY FOG OR LOW STRATUS EXPECTED TO
DEVELOP OVERNIGHT. LOWS SHOULD FALL INTO THE LOWER 70S FOR MOST
LOCALES...A FEW DEGREES WARMER NEAR THE BEACHES.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND STRENGTHENING PIEDMONT TROUGH
WILL BE THE MAIN SURFACE FEATURES THROUGH THE PERIOD. ALOFT A FLAT
MID LEVEL RIDGE WILL EXTEND ACROSS MUCH OF THE SOUTHERN CONUS. DEEP
WESTERLY FLOW IN THE MID LEVELS WILL PUSH TROPICAL MOISTURE
EXPANDING NORTH FROM THE WESTERN GULF OF MEXICO OVER THE REGION MON
AND TUE. INCREASING MOISTURE ALOFT ALONG WITH LOW LEVEL MOISTURE
ADVECTION AROUND WEST SIDE OF BERMUDA HIGH WILL PUSH PRECIPITABLE
WATER VALUES OVER 2 INCHES FOR MUCH OF THE PERIOD.
FLAT MID LEVEL PATTERN MEANS LITTLE TO NO FORCING ALOFT WILL BE
PRESENT. HOWEVER THE COMBINATION OF LOW LEVEL MOISTURE AND SURFACE
HEATING WILL PUSH ML CAPE VALUES TO 1K-2K J/KG FOR MON AND OVER 2K
J/KG ON TUE. CONVECTION WILL INITIALLY BE SLOW TO DEVELOP BUT ONCE
SEA BREEZE AND PIEDMONT TROUGH TAKE SHAPE SHOWERS AND THUNDERSTORMS
SHOULD START POPPING UP. WILL MAINTAIN CHC POP FOR EACH AFTERNOON
BUT WITH SLIGHTLY HIGHER VALUES ON TUE GIVEN SLIGHTLY HIGHER CAPE
VALUES.
TEMPERATURES WILL RUN ABOVE CLIMO THROUGH THE PERIOD. HIGHS WILL
RANGE FROM UPPER 80S ALONG THE IMMEDIATE COAST TO MID 90S INLAND.
LOWS WILL BE IN THE LOW TO MID 70S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND PIEDMONT TROUGH ALONG WITH
ELONGATED MID LEVEL RIDGE WILL REMAIN THE SIGNIFICANT FEATURES
THROUGH THE PERIOD. A COUPLE COLD FRONTS WILL TRY AND MAKE A RUN TO
THE AREA DURING THE NEXT WEEK BUT THEY ARE LIKELY TO STALL AND WASH
OUT JUST NORTH OF THE FORECAST AREA. THE SURFACE AND MID LEVEL
PATTERNS ARE NOT ONES THAT GENERALLY SUPPORT FRONTS MOVING INTO AND
SOUTH OF THE CAPE FEAR REGION. PRECIPITABLE WATER VALUES WILL REMAIN
AROUND 2 INCHES THROUGH THE END OF THE WEEK. DIURNAL HEATING AND
SOUTHWEST FLOW WILL RESULT IN ML CAPE VALUES ABOVE 2K J/KG FOR MUCH
OF THE PERIOD. WEAK GRADIENT WILL ALLOW SEA BREEZE DEVELOPMENT AND
PIEDMONT TROUGH SHOULD BE WELL DEFINED. TYPICAL SUMMER PATTERN WITH
NEAR CLIMO PWATS AND TEMPERATURES NEAR TO SLIGHTLY ABOVE CLIMO
SUGGEST POP WILL BE NEAR CLIMO FOR MUCH OF THE PERIOD...30 PERCENT.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...STILL EXPECT MVFR/IFR CIGS TO DEVELOP EARLY THIS MORNING
WITH THE BEST CHANCES FOR IFR INLAND AT KLBT/KFLO. HAVE BACKED OFF
THE FOG A BIT GIVEN THE INCREASING DEBRIS CLOUDS SPREADING INTO OUR
AREA. WOULD NOT RULE OUT TEMPO IFR VSBYS INLAND...BUT MVFR SEEMS
MORE LIKELY ATTM. EXPECT PERIODS OF MVFR CIGS ALONG THE COAST
BEGINNING AROUND DAYBREAK...WITH THE POTENTIAL FOR SOME ISOLATED
SHOWERS MOVING ONSHORE AS WELL. THE HRRR MODEL SHOWS A FEW SHOWERS
SKIRTING THE COAST THIS MORNING...SO WILL MAINTAIN VCSH FOR
KILM/KCRE/KMYR. THE MVFR CIGS MAY LINGER THROUGH MUCH OF THE
MORNING...BUT CONDITIONS WILL IMPROVE TO VFR BY MIDDAY AND PERSIST
THROUGH THE REST OF THE PERIOD. WINDS WILL BE SOUTH 6-10 KT DURING
THE DAY...POSSIBLY A BIT HIGHER ALONG THE COAST. COULD SEE SOME
ISOLATED SHOWERS ALONG THE SEABREEZE FONT IN THE AFTN...BUT
CONFIDENCE IN TIMING/LOCATION IS TOO LOW TO MENTION IN THE TAFS.
EXTENDED OUTLOOK...INCREASING CHANCES FOR AFTN SHOWERS/TSTMS MONDAY
THROUGH THURSDAY WITH BRIEF AND LOCALIZED PERIODS OF MVFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM SUNDAY...SURFACE HIGH PRESSURE COVERS MOST OF THE
WESTERN AND CENTRAL ATLANTIC OCEAN. THIS SHOULD PRODUCE A
SOUTH-SOUTHEAST WIND TODAY...VEERING MORE SOUTHWESTERLY TONIGHT.
SEAS CURRENTLY AROUND 2 FEET MAY OCCASIONALLY REACH 3 FEET IN A
COMBINATION OF SOUTHEASTERLY SWELL AND LOCAL WIND WAVES...WITH ANY
SCATTERED MORNING SHOWERS EXPECTED TO DISSIPATE BY EARLY AFTERNOON.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND PIEDMONT TROUGH WILL MAINTAIN
SOUTHWEST FLOW OVER THE WATERS THROUGH THE PERIOD. SPEEDS 10 KT OR
LESS WILL INCREASE TO A SOLID 15 KT EACH AFTERNOON AND EVENING AS
THE PIEDMONT TROUGH STRENGTHENS. SEAS IN THE 2 TO 3 FT RANGE.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...MINIMAL CHANGE FOR THE LONG TERM PERIOD. BERMUDA
HIGH REMAINS IN PLACE AS DOES THE PIEDMONT TROUGH. LATE IN THE
PERIOD A WEAKENING COLD FRONT WILL APPROACH FROM THE NORTH BUT IS
EXPECTED TO STALL BEFORE REACHING THE AREA. SOUTHWEST FLOW AROUND 10
KT WILL INCREASE TO A SOLID 15 KT EACH AFTERNOON AND EVENING. SEAS
WILL RUN 2 TO 3 FT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...III
AVIATION...BJR/TRA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
311 AM EDT SUN AUG 31 2014
.SYNOPSIS...
STRENGTHENING BERMUDA HIGH PRESSURE OFFSHORE WILL BRING SUMMERTIME
HEAT AND HUMIDITY THROUGH THE LABOR DAY WEEKEND WITH A FEW SHOWERS
AND THUNDERSTORMS POSSIBLE. A WEAK COLD FRONT WILL APPROACH FROM THE
NORTH LATE NEXT WEEK...BUT WILL LIKELY STALL BEFORE REACHING THE
AREA. BERMUDA HIGH PRESSURE AND A PIEDMONT TROUGH WILL REMAIN THE
DOMINANT FEATURES INTO NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM SUNDAY...SURFACE HIGH PRESSURE COVERS MUCH OF THE WESTERN
AND CENTRAL ATLANTIC OCEAN. THE UPPER LEVEL RIDGE IS CENTERED JUST
OFF THE CAROLINA COAST AND SHOULD KEEP ANY SYNOPTIC IMPULSES
DEFLECTED AWAY TO OUR NORTH AND WEST. 850 MB TEMPERATURES AROUND
+18C THIS AFTERNOON SHOULD RESULT IN HIGH TEMPERATURES IN THE MID
90S FROM MARION AND FLORENCE WESTWARD INTO DARLINGTON COUNTY.
ONSHORE WINDS CLOSER TO THE COAST SHOULD KEEP TEMPERATURES A LITTLE
COOLER...GENERALLY IN THE UPPER 80S TO LOWER 90S.
ALTHOUGH THERE IS CONSIDERABLE DRY AIR ALOFT DUE TO THE UPPER RIDGE
(COLUMN PRECIP WATER VALUES ARE ONLY 1.5 INCHES) VERY RICH MOISTURE
EXISTS IN THE LOWEST LEVELS OF THE ATMOSPHERE. DEWPOINTS IN THE MID
70S THIS MORNING WILL FORTUNATELY MIX DOWN TO NEAR 70 THIS AFTERNOON
INLAND...BUT THAT WILL STILL BE ENOUGH TO PUSH HEAT INDICES TO
100-103 DEGREES ACROSS MOST OF OUR FORECAST AREA. THIS MOISTURE MAY
ALSO FUEL WIDELY SCATTERED SHOWERS NEAR THIS COAST LATER THIS
MORNING...PROBABLY BECOMING LESSER IN COVERAGE THIS AFTERNOON AS
DRIER AIR MIXES DOWNWARD. FORECAST POPS RANGE FROM 20-30 PERCENT...
VIRTUALLY ALL EAST OF I-95.
ANY LINGERING DAYTIME CUMULUS SHOULD QUICKLY DIE AWAY THIS
EVENING... WITH ONLY A LITTLE PATCHY FOG OR LOW STRATUS EXPECTED TO
DEVELOP OVERNIGHT. LOWS SHOULD FALL INTO THE LOWER 70S FOR MOST
LOCALES...A FEW DEGREES WARMER NEAR THE BEACHES.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND STRENGTHENING PIEDMONT TROUGH
WILL BE THE MAIN SURFACE FEATURES THROUGH THE PERIOD. ALOFT A FLAT
MID LEVEL RIDGE WILL EXTEND ACROSS MUCH OF THE SOUTHERN CONUS. DEEP
WESTERLY FLOW IN THE MID LEVELS WILL PUSH TROPICAL MOISTURE
EXPANDING NORTH FROM THE WESTERN GULF OF MEXICO OVER THE REGION MON
AND TUE. INCREASING MOISTURE ALOFT ALONG WITH LOW LEVEL MOISTURE
ADVECTION AROUND WEST SIDE OF BERMUDA HIGH WILL PUSH PRECIPITABLE
WATER VALUES OVER 2 INCHES FOR MUCH OF THE PERIOD.
FLAT MID LEVEL PATTERN MEANS LITTLE TO NO FORCING ALOFT WILL BE
PRESENT. HOWEVER THE COMBINATION OF LOW LEVEL MOISTURE AND SURFACE
HEATING WILL PUSH ML CAPE VALUES TO 1K-2K J/KG FOR MON AND OVER 2K
J/KG ON TUE. CONVECTION WILL INITIALLY BE SLOW TO DEVELOP BUT ONCE
SEA BREEZE AND PIEDMONT TROUGH TAKE SHAPE SHOWERS AND THUNDERSTORMS
SHOULD START POPPING UP. WILL MAINTAIN CHC POP FOR EACH AFTERNOON
BUT WITH SLIGHTLY HIGHER VALUES ON TUE GIVEN SLIGHTLY HIGHER CAPE
VALUES.
TEMPERATURES WILL RUN ABOVE CLIMO THROUGH THE PERIOD. HIGHS WILL
RANGE FROM UPPER 80S ALONG THE IMMEDIATE COAST TO MID 90S INLAND.
LOWS WILL BE IN THE LOW TO MID 70S.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND PIEDMONT TROUGH ALONG WITH
ELONGATED MID LEVEL RIDGE WILL REMAIN THE SIGNIFICANT FEATURES
THROUGH THE PERIOD. A COUPLE COLD FRONTS WILL TRY AND MAKE A RUN TO
THE AREA DURING THE NEXT WEEK BUT THEY ARE LIKELY TO STALL AND WASH
OUT JUST NORTH OF THE FORECAST AREA. THE SURFACE AND MID LEVEL
PATTERNS ARE NOT ONES THAT GENERALLY SUPPORT FRONTS MOVING INTO AND
SOUTH OF THE CAPE FEAR REGION. PRECIPITABLE WATER VALUES WILL REMAIN
AROUND 2 INCHES THROUGH THE END OF THE WEEK. DIURNAL HEATING AND
SOUTHWEST FLOW WILL RESULT IN ML CAPE VALUES ABOVE 2K J/KG FOR MUCH
OF THE PERIOD. WEAK GRADIENT WILL ALLOW SEA BREEZE DEVELOPMENT AND
PIEDMONT TROUGH SHOULD BE WELL DEFINED. TYPICAL SUMMER PATTERN WITH
NEAR CLIMO PWATS AND TEMPERATURES NEAR TO SLIGHTLY ABOVE CLIMO
SUGGEST POP WILL BE NEAR CLIMO FOR MUCH OF THE PERIOD...30 PERCENT.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...STILL EXPECT MVFR/IFR CIGS TO DEVELOP EARLY THIS MORNING
WITH THE BEST CHANCES FOR IFR INLAND AT KLBT/KFLO. HAVE BACKED OFF
THE FOG A BIT GIVEN THE INCREASING DEBRIS CLOUDS SPREADING INTO OUR
AREA. WOULD NOT RULE OUT TEMPO IFR VSBYS INLAND...BUT MVFR SEEMS
MORE LIKELY ATTM. EXPECT PERIODS OF MVFR CIGS ALONG THE COAST
BEGINNING AROUND DAYBREAK...WITH THE POTENTIAL FOR SOME ISOLATED
SHOWERS MOVING ONSHORE AS WELL. THE HRRR MODEL SHOWS A FEW SHOWERS
SKIRTING THE COAST THIS MORNING...SO WILL MAINTAIN VCSH FOR
KILM/KCRE/KMYR. THE MVFR CIGS MAY LINGER THROUGH MUCH OF THE
MORNING...BUT CONDITIONS WILL IMPROVE TO VFR BY MIDDAY AND PERSIST
THROUGH THE REST OF THE PERIOD. WINDS WILL BE SOUTH 6-10 KT DURING
THE DAY...POSSIBLY A BIT HIGHER ALONG THE COAST. COULD SEE SOME
ISOLATED SHOWERS ALONG THE SEABREEZE FONT IN THE AFTN...BUT
CONFIDENCE IN TIMING/LOCATION IS TOO LOW TO MENTION IN THE TAFS.
EXTENDED OUTLOOK...INCREASING CHANCES FOR AFTN SHOWERS/TSTMS MONDAY
THROUGH THURSDAY WITH BRIEF AND LOCALIZED PERIODS OF MVFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM SUNDAY...SURFACE HIGH PRESSURE COVERS MOST OF THE WESTERN
AND CENTRAL ATLANTIC OCEAN. THIS SHOULD PRODUCE A SOUTH-SOUTHEAST
WIND TODAY...VEERING MORE SOUTHWESTERLY TONIGHT. SEAS CURRENTLY
AROUND 2 FEET MAY OCCASIONALLY REACH 3 FEET IN A COMBINATION OF
SOUTHEASTERLY SWELL AND LOCAL WIND WAVES...WITH ANY SCATTERED
MORNING SHOWERS EXPECTED TO DISSIPATE BY EARLY AFTERNOON.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...BERMUDA HIGH AND PIEDMONT TROUGH WILL MAINTAIN
SOUTHWEST FLOW OVER THE WATERS THROUGH THE PERIOD. SPEEDS 10 KT OR
LESS WILL INCREASE TO A SOLID 15 KT EACH AFTERNOON AND EVENING AS
THE PIEDMONT TROUGH STRENGTHENS. SEAS IN THE 2 TO 3 FT RANGE.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...MINIMAL CHANGE FOR THE LONG TERM PERIOD. BERMUDA
HIGH REMAINS IN PLACE AS DOES THE PIEDMONT TROUGH. LATE IN THE
PERIOD A WEAKENING COLD FRONT WILL APPROACH FROM THE NORTH BUT IS
EXPECTED TO STALL BEFORE REACHING THE AREA. SOUTHWEST FLOW AROUND 10
KT WILL INCREASE TO A SOLID 15 KT EACH AFTERNOON AND EVENING. SEAS
WILL RUN 2 TO 3 FT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...III
LONG TERM...III
AVIATION...BJR/TRA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
220 AM EDT SUN AUG 31 2014
.SYNOPSIS...HIGH PRESSURE WILL EXTEND OVER THE REGION THROUGH THE
MIDDLE OF NEXT WEEK. A WEAKENING COLD FRONT WILL APPROACH THE REGION
FROM THE NORTH ON WEDNESDAY... BEFORE RETREATING THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 PM SATURDAY...
THE LATEST SURFACE ANALYSIS CONTINUED TO SHOW A SLACK GRADIENT OVER
CENTRAL NORTH CAROLINA. RADAR SHOWED EARLIER SHOWERS HAD
DIMINISHED...AS THE SEA BREEZE HAD MOVED NORTH AND WEAKENED WHILE
VERY DRY MID-LEVEL AIR MOVED EAST ACROSS CENTRAL AND EASTERN NORTH
CAROLINA ON WATER VAPOR IMAGERY. K INDICES SHOULD FALL INTO THE
TEENS AS BUFR SOUNDINGS FROM THE GFS AND NAM ALONG WITH RAP
SOUNDINGS SHOW AN OVERALL STABLE AIR MASS THEN.
SOME OF THE TEMPERATURES ACROSS CENTRAL NORTH CAROLINA FELL QUICKLY
DURING MID-EVENING...BUT WITH SOME THIN CIRRUS MOVING EAST FROM DEEP
CONVECTION WELL UPSTREAM...ALONG WITH SURFACE DEW POINTS AROUND 70
TO THE LOWER 70S IN MOST LOCATIONS...TEMPERATURES ARE NOT EXPECTED
TO CONTINUE THAT RAPID FALL. LOWS SHOULD MOSTLY BE WITHIN A DEGREE
OR TWO OF 70. SOME LOW CLOUDS REMAIN POSSIBLE LATE TONIGHT
PARTICULARLY AS NOTED ON NAM BUFR SOUNDINGS AND THE SREF
PROBABILISTIC GUIDANCE...AND ALLUDED TO MORE ON THE GFS 18Z MOS
GUIDANCE OUTPUT FROM ITS EARLIER...MORE OPTIMISTIC 12Z GUIDANCE. THE
LATEST HRRR WRF WOULD SUGGEST A BETTER POTENTIAL FOR LOW CLOUDS LATE
TONIGHT IN A NARROW AXIS ALONG AND WEST OF U.S. 1...WHERE SREF
PROBABILITIES ARE A LITTLE HIGHER RELATIVE TO THE REST OF THE AREA
AND CLOSER TO THE HIGHER 925MB WINDS. THOSE 925MB WINDS SEEM A
LITTLE HIGH FOR FOG IN MOST PLACES...TO 20KT TOWARD THE TRIAD LATE
TONIGHT...BUT THE LOWER VALUES OF 10 TO 15KT TOWARD INTERSTATE 95
ALONG WITH EXPECTED DEW POINTS IN THE LOWER 70S COULD ALLOW A LITTLE
MORE NOTICEABLE FOG IN PATCHES TOWARD THERE LATE.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 230 PM SATURDAY...
A SHORT WAVE TROUGH OVER THE MS RIVER VALLEY TO START THE DAY WILL
LIFT TO THE NORTHEAST INTO THE OH VALLEY THROUGH SUNDAY NIGHT.
HOWEVER...ITS ASSOCIATED ENERGY AND DEEP MOISTURE PLUME (EMANATING
FROM THE GULF) WILL LARGELY REMAIN WEST AND NORTH OF CENTRAL NC. IN
ADDITION...THE SUBTROPICAL RIDGE CENTERED OVER THE SOUTHEAST COAST
SHOULD ALSO HELP KEEP THE BETTER RAIN CHANCES WEST OF THE AREA.
THEREFORE...WILL CONTINUE THE FORECAST THINKING OF ONLY ISOLATED TO
WIDELY SCATTERED SHOWERS/STORMS...WITH THE BEST CHANCES ACROSS THE
WEST DUE TO THE PROXIMITY OF THE ABOVE FEATURES. TEMPS WILL CONTINUE
TO BE ABOVE NORMAL...WITH HIGHS GENERALLY IN THE LOWER 90S AND
OVERNIGHT LOWS AROUND 70 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 220 AM SUNDAY...
SUMMERTIME SUBTROPICAL RIDGING REMAINS THE MAIN THEME OF OUR
FORECAST THIS WEEK. THE UPPER RIDGE IS FORECAST TO EXPAND AND
STRENGTHEN EARLY TO MID WEEK... THEN CONTRACT LATE WEEK INTO THE
WEEKEND. HOWEVER... THE RIDGING IS EXPECTED TO REMAIN FIRMLY IN
PLACE OVER THE SOUTHERN AND SOUTHEASTERN STATES THROUGH THE WEEK.
MOISTURE... DAILY INSTABILITY... AND A LEE TROUGH/WEAKENING SURFACE
COLD FRONTS (WED-THU)... THEN AGAIN TOWARD THE WEEKEND WILL PROVIDE
SPARK FOR MAINLY AFTERNOON AND EARLY EVENING THUNDERSTORMS WED-SAT.
SENSIBLE WEATHER WILL INCLUDE AN EXTENDED PERIOD OF HOT/HUMID
WEATHER THROUGH THE WEEK. DAILY LOWS 70-75. HIGHS 90-95. THESE
READINGS WILL BE AROUND 5 DEGREES ABOVE NORMAL. 20 POP TUE... WILL
INCREASE TO 30-50 PERCENT DURING THE AFTERNOON AND EARLY EVENINGS
WED-SAT.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 751 PM SATURDAY...
VFR CONDITIONS WILL CONTINUE THROUGH THE EVENING. LOW LEVEL MOISTURE
REMAINS HIGH ACROSS THE AREA WITH LIGHT SURFACE WINDS... AND IFR
CONDITIONS WITH STRATUS... AND POSSIBLY SOME PATCHY FOG.... ARE
EXPECTED TO DEVELOP IN THE EARLY MORNING HOURS SUNDAY AT
KRDU...KRWI...AND KFAY... WHERE DEWPOINTS ARE HIGHEST. MVFR
CONDITIONS ARE POSSIBLE AT KGSO AND KINT. CONDITIONS WILL RETURN TO
VFR AFTER 12Z SUNDAY... WITH A FEW SHOWERS/THUNDERSTORMS POSSIBLE IN
THE AFTERNOON.
OUTLOOK...A SUMMERTIME PATTERN WILL PERSIST THROUGH EARLY/MID NEXT
WEEK...WITH ISOLATED TO SCATTERED AFTERNOON/EVENING CONVECTION AND A
POTENTIAL FOR EARLY MORNING FOG/STRATUS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PWB
NEAR TERM...DJF
SHORT TERM...KRD
LONG TERM...PWB
AVIATION...SEC/KRD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1259 AM EDT SUN AUG 31 2014
.SYNOPSIS...
STRENGTHENING BERMUDA HIGH PRESSURE OFFSHORE WILL BRING SUMMERTIME
HEAT AND HUMIDITY THROUGH THE LABOR DAY WEEKEND WITH A FEW SHOWERS
AND THUNDERSTORMS POSSIBLE. A WEAK COLD FRONT WILL APPROACH FROM THE
NORTH LATE NEXT WEEK...BUT WILL LIKELY STALL BEFORE REACHING THE
AREA. BERMUDA HIGH PRESSURE AND A PIEDMONT TROUGH WILL REMAIN THE
DOMINANT FEATURES INTO NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 100 AM SATURDAY...NO SIGNIFICANT CHANGES ARE NEEDED TO THE
FORECAST. PREVIOUS DISCUSSION FROM 1000 PM FOLLOWS...
MUCH LIKE THE PAST COUPLE OF NIGHTS...A FEW SHOWERS HAVE BEGUN TO
DEVELOP OFFSHORE. SOME OF THE HIGHER RESOLUTION MODELS ARE SHOWING
THESE SHOWERS FLIRTING WITH THE IMMEDIATE COAST OVERNIGHT. GIVEN THE
PREVAILING SOUTHERLY FLOW...THE HIGHEST RISK FOR SHOWERS WILL BE
ACROSS BRUNSWICK COUNTY AND THE SOUTHERN PORTIONS OF NEW HANOVER
COUNTY.
WILL INCLUDE PATCHY LATE NIGHT FOG ACROSS MOST OF THE AREA...
GREATEST COVERAGE IS EXPECTED AWAY FROM THE IMMEDIATE COAST WHERE
MIXING WILL BE LEAST. MUCH LIKE LAST NIGHT...EXPECT A FOG AND
STRATUS MIX LATE. HIGH LEVEL CONVECTIVE DEBRIS CLOUDINESS WILL
CONTINUE TO SPILL ACROSS THE FORECAST AREA. THESE CLOUDS ARE FROM
UPSTREAM CONVECTION AND WILL BE MAINLY THIN ACROSS THE EASTERN
CAROLINAS OVERNIGHT.
LIGHT TO CLAM WINDS AND ONLY A HINT OF A WEAK NOCTURNAL JET SHOULD
ALLOW FOR AT LEAST SOME RADIATIONAL COOLING. DID NOT STRAY TOO FAR
FROM THE LOWS OF SAT...WHICH WILL PUT MOST LOCATIONS IN THE LOWER TO
MID 70S OVERNIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 330 PM SATURDAY...MODELS REMAIN SIMILAR AND VIGILANT WITH
REGARD TO KEEPING RIDGING ALOFT ACROSS THE FORECAST AREA THRU-OUT
THE SHORT TERM PERIOD. SOME FLATTENING DOES OCCUR DURING LATE IN
THE SHORT TERM PERIOD AS SUCCESSIVE MID-UPPER LEVEL S/W TROFS PUSH
BASICALLY FROM WEST TO EAST ACROSS THE U.S....WITH THE BEST
DYNAMICS ASSOCIATED WITH EACH OF THEM REMAINING NORTH OF THE FA.
NEVERTHELESS...WITH TIME...THEY DO PARTIALLY ERODE THE MID-UPPER
RIDGING ACROSS THE FA BY DAYBREAK TUE.
AT THE SFC...THE STALLED E-W ORIENTED FRONTAL BOUNDARY ACROSS
CENTRAL NC...WILL SLOWLY DISSIPATE AS IT RETURNS BACK TO THE NORTH
DURING THIS PERIOD. THE RIDGE AXIS EXTENDING FROM THE 1025+ WESTERN
ATLANTIC HIGH...WILL BECOME THE DOMINATE WX FEATURE TO AFFECT THE
EASTERN CAROLINAS MONDAY THRU TUESDAY. IN ADDITION...THE PIEDMONT
TROF ACROSS THE CENTRAL CAROLINAS WILL BECOME MORE PREVALENT BY
LABOR DAY AND BEYOND.
AS FOR PCPN CHANCES...THE AFTERNOON/EVENING SEA BREEZE AND
PREVALENT PIEDMONT TROF WILL PROVIDE THE FORCING FOR DIURNALLY
DRIVEN CONVECTION BOTH DAYS. MODELS DO INDICATE A BETTER DEFINED
PIEDMONT TROF BY MONDAY AND THUS THE OVERALL POP SCHEME WILL BE
ADVERTISED WITH A SLIGHTLY HIGHER CHANCE MONDAY OVER SUNDAY. LATEST
SREF ALSO INDICATE A HIGHER POP FOR MONDAY OVER TUE. SEE NO REASON
TO GO AGAINST THIS LAYOUT OF POPS. AS FOR DAILY MAX AND MIN
TEMPS...WILL STAY CLOSER TO THE NAM MOS GUIDANCE DUE TO ITS BETTER
PERFORMANCE THE PAST 5 DAYS WHEN COMPARED TO THE OTHER AVBL MODEL
MOS GUIDANCE.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 330 PM SATURDAY...MID TO UPPER RIDGE HOLDING ON OVER
SOUTHERN CONUS WHILE SHORTWAVES RIDE BY IN NORTHERN STREAM FLOW.
THESE SHORTWAVES WILL DRIVE A FEW COLD FRONTS EAST BUT TRAILING
END SHOULD REMAIN NORTH OF LOCAL AREA. THESE BOUNDARIES MAY MOVE
CLOSE ENOUGH TO AFFECT THE WINDS OR PRODUCE SOME DRIER AIR TO MOVE
IN ALOFT. OVERALL BERMUDA HIGH PRESSURE TO THE EAST AND PIEDMONT
TROUGH TO THE WEST WILL REMAIN THE MAIN PLAYERS THROUGH THE
WEEK...MAINTAINING A WARM HUMID AIR MASS. EXPECT LOCALIZED
CONVECTION POSSIBLE EACH DAY WITH FOCUS ALONG SEA BREEZE BOUNDARY
AND PIEDMONT TROUGH INLAND. A WEAK SOUTHERLY RETURN FLOW SHOULD BE
ENHANCED BY SEA BREEZE EACH AFTERNOON. DEWPOINT TEMPS UP ABOVE 70
WILL KEEP OVERNIGHT LOWS IN 70S AND DAYTIME HIGHS WILL REACH CLOSE
TO 90 ALONG THE COAST AND INTO THE MID 90S INLAND.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...STILL EXPECT MVFR/IFR CIGS TO DEVELOP EARLY THIS MORNING
WITH THE BEST CHANCES FOR IFR INLAND AT KLBT/KFLO. HAVE BACKED OFF
THE FOG A BIT GIVEN THE INCREASING DEBRIS CLOUDS SPREADING INTO OUR
AREA. WOULD NOT RULE OUT TEMPO IFR VSBYS INLAND...BUT MVFR SEEMS
MORE LIKELY ATTM. EXPECT PERIODS OF MVFR CIGS ALONG THE COAST
BEGINNING AROUND DAYBREAK...WITH THE POTENTIAL FOR SOME ISOLATED
SHOWERS MOVING ONSHORE AS WELL. THE HRRR MODEL SHOWS A FEW SHOWERS
SKIRTING THE COAST THIS MORNING...SO WILL MAINTAIN VCSH FOR
KILM/KCRE/KMYR. THE MVFR CIGS MAY LINGER THROUGH MUCH OF THE
MORNING...BUT CONDITIONS WILL IMPROVE TO VFR BY MIDDAY AND PERSIST
THROUGH THE REST OF THE PERIOD. WINDS WILL BE SOUTH 6-10 KT DURING
THE DAY...POSSIBLY A BIT HIGHER ALONG THE COAST. COULD SEE SOME
ISOLATED SHOWERS ALONG THE SEABREEZE FONT IN THE AFTN...BUT
CONFIDENCE IN TIMING/LOCATION IS TOO LOW TO MENTION IN THE TAFS.
EXTENDED OUTLOOK...INCREASING CHANCES FOR AFTN SHOWERS/TSTMS MONDAY
THROUGH THURSDAY WITH BRIEF AND LOCALIZED PERIODS OF MVFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 100 AM SUNDAY...TWO MINOR CHANGES HAVE BEEN MADE TO THE
FORECAST WITH THIS EARLY MORNING NEAR-TERM UPDATE. THE FIRST WAS TO
TRIM BACK SEA HEIGHT FORECASTS BASED ON LATEST BUOY DATA SHOWING
NOTHING HIGHER THAN 2 FEET NEAR OR OFFSHORE. THE OTHER CHANGE WAS TO
INDICATE IN THE HIGH-RESOLUTION GRIDDED FORECAST A WEAK LANDBREEZE
DEVELOPING JUST BEFORE DAYBREAK WITH LIGHT NORTH TO NORTHWEST WINDS
NEAR THE BEACHES. PREVIOUS DISCUSSION FROM 1000 PM FOLLOWS...
HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL KEEP A SOUTHERLY FLOW
ACROSS THE WATERS OVERNIGHT...UP TO AROUND 10 KT. SEAS WILL REMAIN
NEAR 3 FT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 330 PM SATURDAY...THE SFC PRESSURE PATTERN FOR BOTH SUNDAY
AND LABOR DAY ILLUSTRATE THE RIDGE AXIS EXTENDING FROM THE WESTERN
ATLANTIC HIGH WILL REMAIN JUST SOUTH OF THE LOCAL WATERS. THIS
POSITIONING WILL RESULT WITH A SOUTH TO SOUTHWEST WIND DIRECTION
ACROSS THE WATERS...AND POSSIBLY BECOMING MORE WSW LATE IN THE
PERIOD. THE SFC PG WILL SLOWLY TIGHTEN-SOME ACROSS THE LOCAL
WATERS AS THE PIEDMONT TROF ACROSS THE EASTERN CAROLINAS BECOMES
BETTER ESTABLISHED. LOOK FOR WIND SPEEDS INITIALLY AROUND 10 KT AT
THE START...INCREASING TO 10 TO 15 KT OR POSSIBLY A SOLID 15 KT
WITH GUSTS AROUND 20 KT BY MONDAY AFTN AND NIGHT. A DECENT SEA
BREEZE CIRCULATION WILL SETUP EACH AFTN AND EVENG...AFFECTING THE
NEARSHORE WATERS WITHIN 10 NM FROM THE COAST WITH HIGHER WIND
SPEEDS.
SIGNIFICANT SEAS WILL RUN A SOLID 2 TO 3 FT...WITH 4 FOOTERS NOT
OUT OF THE QUESTION DURING THE PEAK OF THE SEA BREEZE EACH
DAY...BUT MORE-SO DURING MONDAY AFTN AND NIGHT DUE TO SOLID
SYNOPTIC WINDS AROUND 15 KT. A SOLID 2 FOOT EASTERLY GROUND SWELL
EXHIBITING 8 TO 10 SECOND PERIODS...WILL INITIALLY DOMINATE THE
SIGNIFICANT SEAS EARLY IN THE PERIOD. BUT AS SYNOPTIC AND
MESOSCALE DRIVEN WINDS INCREASE ACROSS THE AREA WATERS...LOOK FOR
AN INCREASE TO THE LOCALLY PRODUCED WIND WAVES TO COMBINE WITH THE
GROUND SWELL AND PRODUCE THOSE 4 FOOTERS BY LATE IN THIS SHORT
TERM PERIOD.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 330 PM SATURDAY...BERMUDA HIGH OFF SHORE AND PIEDMONT
TROUGH INLAND WILL MAINTAIN A PERSISTENT LIGHT SOUTHERLY RETURN
FLOW THROUGH MUCH OF THE WEEK AROUND 10 TO 15 KTS. THE FLOW WILL
BE ENHANCED BY THE SEA BREEZE EACH AFTN. THE WEAK SOUTHERLY PUSH
WILL KEEP SEAS 1 TO 3 FT WITH A SLIGHT CHOP EACH AFTN. WINDS MAY
LIGHTEN FURTHER TO LESS THAN 10 KTS BY THURS WITH A FURTHER DROP
IN SEAS DOWN TO 2 FT OR LESS
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RJD/TRA
SHORT TERM...DCH
LONG TERM...RGZ
AVIATION...BJR/TRA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1235 PM CDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 1227 PM CDT SUN AUG 31 2014
BROAD AREA OF PRECIPITATION HAS PUSHED OFF TO THE EAST. OF TO THE
WEST...SHOWERS ARE STARTING TO RE-DEVELOP WITH THE NEXT WAVE
PUSHING THROUGH BROAD CYCLONIC FLOW. WITH HIT-AND-MISS SHOWER
ACTIVITY EXPECTED...HAVE BROAD BRUSHED LOW POPS FOR LATER THIS
AFTERNOON. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 824 AM CDT SUN AUG 31 2014
SHOWER ACTIVITY WITH A FEW WEAK THUNDERSTORMS CONTINUES MAINLY
ALONG AND EAST OF A LINE FROM JAMESTOWN TO HARVEY TO BOTTINEAU.
HAVE ADJUSTED POPS ACCORDINGLY FOR THIS...AND HAVE KEPT SOME LOW
POPS IN THE FAR SOUTHWEST AS SOME WEAK SHOWERS START TO DEVELOP
AND MOVE INTO THAT AREA. HAVE ALSO EXPANDED PATCHY FOG COVERAGE
FOR THE MORNING AS VISIBILITY HAS DROPPED OVER A VARIETY OF
LOCATIONS IN WESTERN NORTH DAKOTA. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 633 AM CDT SUN AUG 31 2014
STILL GETTING SOME THUNDERSTORM REDEVELOPMENT ACROSS EAST CENTRAL
NORTH DAKOTA IN STUTSMAN COUNTY. APPEARS THIS WILL TRACK EAST FOR
THE NEXT FEW HOURS. AREAS OF FOG SPREADING ACROSS THE FAR NORTH.
THIS WILL LAST THROUGH MID MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT SUN AUG 31 2014
FOCUS IN THE SHORT TERM WILL BE ON THE EXITING RAINFALL THROUGH
THIS MORNING AND THE CHANCES FOR RAIN LATER TODAY.
THE HRRR MODEL HAS DONE A DECENT JOB OF FORECASTING PRECIPITATION
THROUGH THE NIGHT AND EARLY THIS MORNING AND POPS MIMIC THE 05 UTC
HRRR PRECIPITATION AS IT PROGRESSES NORTHEAST. MOST ALL HEAVY RAIN
HAS PUSHED EAST INTO EASTERN NORTH DAKOTA...HOWEVER A VERY THIN BAND
OF SHOWERS IS SLOWLY MOVING EAST ACROSS WESTERN NORTH DAKOTA. AS OF
0730 UTC THE BAND DROPPED HEAVY RAIN AT THE DICKINSON AIRPORT. DO
NOT EXPECT THIS BAND...AT LEAST THE HEAVY RAIN ASSOCIATED WITH
IT...TO LAST MUCH LONGER INTO THE MORNING HOURS.
LOOKING FORWARD TO THIS AFTERNOON AND TONIGHT MODELS AGREE ON A
BROAD TROUGH SETTING UP OVER THE NORTHERN PLAINS TODAY WITH A WEAK
SHORT WAVE MOVING THROUGH IN THE AFTERNOON AND NIGHT. THE 00 UTC
MODELS ARE HAVING A DIFFICULT TIME NAILING DOWN WHERE THE
PRECIPITATION WILL FALL EXACTLY...HOWEVER ONLY LIGHT TO MODERATE
SHOWERS ARE EXPECTED. AT THE MOST EXPECTING A SOME SCATTERED SHOWERS
AND A FEW RUMBLES OF THUNDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 358 AM CDT SUN AUG 31 2014
THE EXTENDED BEGINS WITH A COOL CYCLONIC FLOW ALOFT ACROSS THE
NORTHERN PLAINS MONDAY INTO TUESDAY. THIS SHOULD AT LEAST SUPPORT
SOME WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. HIGHS
MONDAY AND TUESDAY WILL BE A BIT COOL IN THE UPPER 60S TO LOWER
70S. BY WEDNESDAY THE FLOW ALOFT BECOMES MORE ZONAL AS THE
IN BETWEEN SHORTWAVE TROUGHS. BY THURSDAY THE GFS/ECMWF/GEM BRING
THE NEXT SHORTWAVE TROUGH INTO THE NORTHERN PLAINS WHICH IS
PRETTY CONSISTENT WITH THE PAST FEW MODEL RUNS. THE ECMWF/GEM ARE A
BIT MORE ROBUST IN QPF FORECAST FOR NORTH DAKOTA. LIKED THE
ALLBLEND VERSION OF POPS FOR WEDNESDAY NIGHT AT 30 POPS FOR NOW.
AFTER THURSDAY THE FLOW ALOFT BECOMES SEPARATED BETWEEN A NORTHERN
AND SOUTHERN STREAM FLOW WITH THE GFS MORE PRONOUNCED IN THE FLOW
SEPARATION AROUND A CUTOFF LOW OFF THE WEST COAST. THE BASIC
RESULT WILL BE A QUIET PERIOD FRIDAY INTO SATURDAY AS THE FLOW
MERGES ALOFT OVER THE NORTHERN PLAINS RESULTING IN WEAK SUDSIDENCE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1227 PM CDT SUN AUG 31 2014
ISOLD -SHRA/-TSRA ARE EXPECTED THROUGH MUCH OF THE FORECAST
PERIOD...THOUGH WILL REFRAIN FROM MENTIONING IN INDIVIDUAL
TERMINAL FORECASTS GIVEN THE LOW PROBABILITY OF ANY VIS/CIG
RESTRICTIONS. WILL MONITOR AND UPDATE AS NEEDED. MVFR CIGS WILL
CONTINUE TO AFFECT THE KJMS TERMINAL THROUGH EARLY AFTERNOON.
OTHERWISE...VFR CONDITIONS ARE EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...MM
LONG TERM...WAA
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
837 AM CDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 824 AM CDT SUN AUG 31 2014
SHOWER ACTIVITY WITH A FEW WEAK THUNDERSTORMS CONTINUES MAINLY
ALONG AND EAST OF A LINE FROM JAMESTOWN TO HARVEY TO BOTTINEAU.
HAVE ADJUSTED POPS ACCORDINGLY FOR THIS...AND HAVE KEPT SOME LOW
POPS IN THE FAR SOUTHWEST AS SOME WEAK SHOWERS START TO DEVELOP
AND MOVE INTO THAT AREA. HAVE ALSO EXPANDED PATCHY FOG COVERAGE
FOR THE MORNING AS VISIBILITY HAS DROPPED OVER A VARIETY OF
LOCATIONS IN WESTERN NORTH DAKOTA. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 633 AM CDT SUN AUG 31 2014
STILL GETTING SOME THUNDERSTORM REDEVELOPMENT ACROSS EAST CENTRAL
NORTH DAKOTA IN STUTSMAN COUNTY. APPEARS THIS WILL TRACK EAST FOR
THE NEXT FEW HOURS. AREAS OF FOG SPREADING ACROSS THE FAR NORTH.
THIS WILL LAST THROUGH MID MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT SUN AUG 31 2014
FOCUS IN THE SHORT TERM WILL BE ON THE EXITING RAINFALL THROUGH
THIS MORNING AND THE CHANCES FOR RAIN LATER TODAY.
THE HRRR MODEL HAS DONE A DECENT JOB OF FORECASTING PRECIPITATION
THROUGH THE NIGHT AND EARLY THIS MORNING AND POPS MIMIC THE 05 UTC
HRRR PRECIPITATION AS IT PROGRESSES NORTHEAST. MOST ALL HEAVY RAIN
HAS PUSHED EAST INTO EASTERN NORTH DAKOTA...HOWEVER A VERY THIN BAND
OF SHOWERS IS SLOWLY MOVING EAST ACROSS WESTERN NORTH DAKOTA. AS OF
0730 UTC THE BAND DROPPED HEAVY RAIN AT THE DICKINSON AIRPORT. DO
NOT EXPECT THIS BAND...AT LEAST THE HEAVY RAIN ASSOCIATED WITH
IT...TO LAST MUCH LONGER INTO THE MORNING HOURS.
LOOKING FORWARD TO THIS AFTERNOON AND TONIGHT MODELS AGREE ON A
BROAD TROUGH SETTING UP OVER THE NORTHERN PLAINS TODAY WITH A WEAK
SHORT WAVE MOVING THROUGH IN THE AFTERNOON AND NIGHT. THE 00 UTC
MODELS ARE HAVING A DIFFICULT TIME NAILING DOWN WHERE THE
PRECIPITATION WILL FALL EXACTLY...HOWEVER ONLY LIGHT TO MODERATE
SHOWERS ARE EXPECTED. AT THE MOST EXPECTING A SOME SCATTERED SHOWERS
AND A FEW RUMBLES OF THUNDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 358 AM CDT SUN AUG 31 2014
THE EXTENDED BEGINS WITH A COOL CYCLONIC FLOW ALOFT ACROSS THE
NORTHERN PLAINS MONDAY INTO TUESDAY. THIS SHOULD AT LEAST SUPPORT
SOME WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. HIGHS
MONDAY AND TUESDAY WILL BE A BIT COOL IN THE UPPER 60S TO LOWER
70S. BY WEDNESDAY THE FLOW ALOFT BECOMES MORE ZONAL AS THE
IN BETWEEN SHORTWAVE TROUGHS. BY THURSDAY THE GFS/ECMWF/GEM BRING
THE NEXT SHORTWAVE TROUGH INTO THE NORTHERN PLAINS WHICH IS
PRETTY CONSISTENT WITH THE PAST FEW MODEL RUNS. THE ECMWF/GEM ARE A
BIT MORE ROBUST IN QPF FORECAST FOR NORTH DAKOTA. LIKED THE
ALLBLEND VERSION OF POPS FOR WEDNESDAY NIGHT AT 30 POPS FOR NOW.
AFTER THURSDAY THE FLOW ALOFT BECOMES SEPARATED BETWEEN A NORTHERN
AND SOUTHERN STREAM FLOW WITH THE GFS MORE PRONOUNCED IN THE FLOW
SEPARATION AROUND A CUTOFF LOW OFF THE WEST COAST. THE BASIC
RESULT WILL BE A QUIET PERIOD FRIDAY INTO SATURDAY AS THE FLOW
MERGES ALOFT OVER THE NORTHERN PLAINS RESULTING IN WEAK SUDSIDENCE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 633 AM CDT SUN AUG 31 2014
FRONTAL BOUNDARY IS MOVING EAST ACROSS THE REGION THIS MORNING. ONLY
KJMS IS AHEAD OF THE FRONT AND BY 18Z THE FRONT SHOULD BE PAST KJMS.
LOW CLOUDS WILL STICK AROUND THROUGH THE MORNING AT KJMS...KBIS...
AND KMOT PROVIDING IFR TO MVFR CONDITIONS. EXPECT CONDITIONS TO
IMPROVE EARLY THIS AFTERNOON FROM WEST TO EAST. SHOWERS AND
THUNDERSTORMS WILL ALSO BE POSSIBLE THROUGH THE 12Z TAF
PERIOD...HOWEVER SCATTERED IN NATURE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...MM
LONG TERM...WAA
AVIATION...MM
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
710 AM CDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 705 AM CDT SUN AUG 31 2014
CONVECTION ASSOCIATED WITH MID/UPPER LEVEL CIRCULATION MOVING
NORTHEAST 30KTS...WITH REDEVELOPMENT SOUTHWEST OF THE DEVILS LAKE
BASIN UNDER 700 MB CAA. AREA HAS GRADUALLY SLOWED DURING THE PAST
SEVERAL HOURS AS UPPER CIRCULATION APPEARS TO BE INTENSIFYING.
REDEVELOPMENT APPEARS AIDED BY 850MB MOIST TRANSPORT AND 0-6KM
BULK SHEAR OF 40KTS. LATEST HRRR AND 03Z HOPWRF SUPPORT THESE
TRENDS THROUGH 18Z. HAVE TWEAKED POPS/WX/WINDS BASED ON CURRENT
CONDITIONS AND HIGH-RES MODEL FCSTS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM CDT SUN AUG 31 2014
FOR THE NEXT 6 TO 12 HOURS THE MAIN CONCERN IS THE CONVECTION AND
RISK FOR SEVERE. AS OF 08Z A LINE OF TSRA EXTENDED FROM
KDVL...KS32 TO KGWR MOVG EAST 35 KTS. THIS LINE IS MOVING INTO AN
AREA OF INCREASINGLY STABLE AIR AND APPEARS TO BE OUTRUNNING THE
LOWER LEVEL FORCING. THE NAM12 AND GFS40 HAD BEEN INCREASING THE
BULK 0-6KM SHEAR TO NEAR 50KTS IN THE DEVILS LAKE BASIN...WHICH
DOES NOT YET APPEAR TO BE THE CASE. HAVE TRIED TO TIME THE TSRA
ACROSS THE CWFA THIS FIRST 12 HOURS BLENDING INHERITED FCST AND
HRRR/NAM/WRF MODEL MOVEMENT.
THE FIRST WAVE ASSOCIATED WITH CONVECTION MOVES EAST BY
18Z...WITH SECOND FAST WAVE MOVING INTO WY AS OF 08Z. AS THE UPPER
WAVES ARE PROGRESSIVE AND THE SYNOPTIC SCALE MODELS ARE IN FAIR
AGREEMENT WITH THE HIGH-RES MODELS...HAVE TRENDED THE BULK OF THE
TSRA/RASH OVER THE EASTERN HALF CWFA BY 00Z. MAY HAVE HELD ON TO
POPS TOO LONG POST 18Z...BUT THIS IS DIFFICULT TO ASCERTAIN ATTM.
THE FCST PRESENCE OF THE LOW LEVEL BOUNDARY AND INSTABILITY 18Z-
00Z ARGUES FOR HOLDING ONTO POPS.
SECOND SHORT WAVE FORECAST TO MOVE ACROSS THE SOUTHERN HALF OF
THE FA 00Z TO 06Z MONDAY SO HAVE HELD ON TO CHC POPS THROUGH 06Z
THEN ENDED RAIN RISK FOR MONDAY. HIGH TEMPERATURES TODAY WILL BE
HIGHLY DEPENDENT ON THE CLOUD COVER...THICKNESSES ARE HIGH ENOUGH
OVER THE SOUTH TO SUPPORT UPPER 70S TO LOWER 80S. HAVE USED THE
LOCAL BIAS CORRECTED TEMPERATURE MODEL FOR TODAY - TUESDAY AS IT
SEEMS TO HAVE SUPERIOR SKILL OF LATE.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 AM CDT SUN AUG 31 2014
FLOW ALOFT TURNS FLAT WEST-NORTHWEST BEHIND SECOND WAVE BUT
HEIGHTS DO NOT FALL APPRECIABLY. THE NEXT SHORTWAVE AND ASSOCIATED
SURFACE REFLECTION IMPACTS THE SOUTHERN CWFA MONDAY NIGHT. MODELS
SUGGEST NEXT WAVE FOR TUESDAY FOCUSED MORE ALONG AND NORTH OF THE
HIGHWAY 2 CORRIDOR FOR TUESDAY AFTERNOON AND EVENING...WITH ONLY
CHC POPS.
WEDNESDAY THROUGH SATURDAY...THE NEXT UPPER TROUGH WILL MOVE INTO
THE NORTHERN ROCKIES AT THE START OF THE PERIOD...THEN MOVING OFF
INTO MANITOBA BY THURSDAY. THE SFC LOW WILL MOVE BY TO OUR SOUTH AND
WE SHOULD SEE PLENTY OF PRECIP WITH A BOUNDARY NEARBY...ALTHOUGH THE
MODELS DIFFER ON EXACT TIMING AND PLACEMENT OF THE LOW. WILL
CONTINUE TO KEEP FAIRLY HIGH POPS FOR WEDNESDAY NIGHT AND SOME
LINGERING IN THE EST INTO THURSDAY AS A COLD FRONT COMES THROUGH.
SFC HIGH PRESSURE BUILDING IN FOR THE END OF THE PERIOD WILL BRING
DRY CONDITIONS AND COOLER TEMPERATURES. THE ECMWF AND GFS START TO
DIVERGE BY SATURDAY...SO KEPT ALLBLEND POPS FOR THE TIME BEING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 636 AM CDT SUN AUG 31 2014
TYPICAL MIXTURE OF VFR/MVFR/IFR CIGS FOUND IN THE PRESENCE OF TSRA
AND SHRA AS AREA OF CONVECTION MOVES NORTHEAST 30 TO 35 KTS. SFC
LOW AND ASSOC WNDSHFT FCST TO MOVE TO KGFK...KFAR LINE 19Z TO
20Z...REACHING KBJI AROUND 010200Z. AFTER INITIAL CONVECTION MOVES
NORTHEAST TAF SITES...EXPCT VFR CIGS AND VSBY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...EWENS
SHORT TERM...EWENS
LONG TERM...JR/EWENS
AVIATION...EWENS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
639 AM CDT SUN AUG 31 2014
.UPDATE...
ISSUED AT 633 AM CDT SUN AUG 31 2014
STILL GETTING SOME THUNDERSTORM REDEVLOPMENT ACROSS EAST CENTRAL
NORTH DAKOTA IN STUTSMAN COUNTY. APPEARS THIS WILL TRACK EAST FOR
THE NEXT FEW HOURS. AREAS OF FOG SPEADING ACROSS THE FAR NORTH.
THIS WILL LAST THROUGH MID MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT SUN AUG 31 2014
FOCUS IN THE SHORT TERM WILL BE ON THE EXITING RAINFALL THROUGH
THIS MORNING AND THE CHANCES FOR RAIN LATER TODAY.
THE HRRR MODEL HAS DONE A DECENT JOB OF FORECASTING PRECIPITATION
THROUGH THE NIGHT AND EARLY THIS MORNING AND POPS MIMIC THE 05 UTC
HRRR PRECIPITATION AS IT PROGRESSES NORTHEAST. MOST ALL HEAVY RAIN
HAS PUSHED EAST INTO EASTERN NORTH DAKOTA...HOWEVER A VERY THIN BAND
OF SHOWERS IS SLOWLY MOVING EAST ACROSS WESTERN NORTH DAKOTA. AS OF
0730 UTC THE BAND DROPPED HEAVY RAIN AT THE DICKINSON AIRPORT. DO
NOT EXPECT THIS BAND...AT LEAST THE HEAVY RAIN ASSOCIATED WITH
IT...TO LAST MUCH LONGER INTO THE MORNING HOURS.
LOOKING FORWARD TO THIS AFTERNOON AND TONIGHT MODELS AGREE ON A
BROAD TROUGH SETTING UP OVER THE NORTHERN PLAINS TODAY WITH A WEAK
SHORT WAVE MOVING THROUGH IN THE AFTERNOON AND NIGHT. THE 00 UTC
MODELS ARE HAVING A DIFFICULT TIME NAILING DOWN WHERE THE
PRECIPITATION WILL FALL EXACTLY...HOWEVER ONLY LIGHT TO MODERATE
SHOWERS ARE EXPECTED. AT THE MOST EXPECTING A SOME SCATTERED SHOWERS
AND A FEW RUMBLES OF THUNDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 358 AM CDT SUN AUG 31 2014
THE EXTENDED BEGINS WITH A COOL CYCLONIC FLOW ALOFT ACROSS THE
NORTHERN PLAINS MONDAY INTO TUESDAY. THIS SHOULD AT LEAST SUPPORT
SOME WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. HIGHS
MONDAY AND TUESDAY WILL BE A BIT COOL IN THE UPPER 60S TO LOWER
70S. BY WEDNESDAY THE FLOW ALOFT BECOMES MORE ZONAL AS THE
IN BETWEEN SHORTWAVE TROUGHS. BY THURSDAY THE GFS/ECMWF/GEM BRING
THE NEXT SHORTWAVE TROUGH INTO THE NORTHERN PLAINS WHICH IS
PRETTY CONSISTENT WITH THE PAST FEW MODEL RUNS. THE ECMWF/GEM ARE A
BIT MORE ROBUST IN QPF FORECAST FOR NORTH DAKOTA. LIKED THE
ALLBLEND VERSION OF POPS FOR WEDNESDAY NIGHT AT 30 POPS FOR NOW.
AFTER THURSDAY THE FLOW ALOFT BECOMES SEPARATED BETWEEN A NORTHERN
AND SOUTHERN STREAM FLOW WITH THE GFS MORE PRONOUNCED IN THE FLOW
SEPARATION AROUND A CUTOFF LOW OFF THE WEST COAST. THE BASIC
RESULT WILL BE A QUIET PERIOD FRIDAY INTO SATURDAY AS THE FLOW
MERGES ALOFT OVER THE NORTHERN PLAINS RESULTING IN WEAK SUDSIDENCE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 633 AM CDT SUN AUG 31 2014
FRONTAL BOUNDARY IS MOVING EAST ACROSS THE REGION THIS MORNING. ONLY
KJMS IS AHEAD OF THE FRONT AND BY 18Z THE FRONT SHOULD BE PAST KJMS.
LOW CLOUDS WILL STICK AROUND THROUGH THE MORNING AT KJMS...KBIS...
AND KMOT PROVIDING IFR TO MVFR CONDITIONS. EXPECT CONDITIONS TO
IMPROVE EARLY THIS AFTERNOON FROM WEST TO EAST. SHOWERS AND
THUNDERSTORMS WILL ALSO BE POSSIBLE THROUGH THE 12Z TAF
PERIOD...HOWEVER SCATTERED IN NATURE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...MM
LONG TERM...WAA
AVIATION...MM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
359 AM CDT SUN AUG 31 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CDT SUN AUG 31 2014
FOCUS IN THE SHORT TERM WILL BE ON THE EXITING RAINFALL THROUGH
THIS MORNING AND THE CHANCES FOR RAIN LATER TODAY.
THE HRRR MODEL HAS DONE A DECENT JOB OF FORECASTING PRECIPITATION
THROUGH THE NIGHT AND EARLY THIS MORNING AND POPS MIMIC THE 05 UTC
HRRR PRECIPITATION AS IT PROGRESSES NORTHEAST. MOST ALL HEAVY RAIN
HAS PUSHED EAST INTO EASTERN NORTH DAKOTA...HOWEVER A VERY THIN BAND
OF SHOWERS IS SLOWLY MOVING EAST ACROSS WESTERN NORTH DAKOTA. AS OF
0730 UTC THE BAND DROPPED HEAVY RAIN AT THE DICKINSON AIRPORT. DO
NOT EXPECT THIS BAND...AT LEAST THE HEAVY RAIN ASSOCIATED WITH
IT...TO LAST MUCH LONGER INTO THE MORNING HOURS.
LOOKING FORWARD TO THIS AFTERNOON AND TONIGHT MODELS AGREE ON A
BROAD TROUGH SETTING UP OVER THE NORTHERN PLAINS TODAY WITH A WEAK
SHORT WAVE MOVING THROUGH IN THE AFTERNOON AND NIGHT. THE 00 UTC
MODELS ARE HAVING A DIFFICULT TIME NAILING DOWN WHERE THE
PRECIPITATION WILL FALL EXACTLY...HOWEVER ONLY LIGHT TO MODERATE
SHOWERS ARE EXPECTED. AT THE MOST EXPECTING A SOME SCATTERED SHOWERS
AND A FEW RUMBLES OF THUNDER.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 358 AM CDT SUN AUG 31 2014
THE EXTENDED BEGINS WITH A COOL CYCLONIC FLOW ALOFT ACROSS THE
NORTHERN PLAINS MONDAY INTO TUESDAY. THIS SHOULD AT LEAST SUPPORT
SOME WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS. HIGHS
MONDAY AND TUESDAY WILL BE A BIT COOL IN THE UPPER 60S TO LOWER
70S. BY WEDNESDAY THE FLOW ALOFT BECOMES MORE ZONAL AS THE
IN BETWEEN SHORTWAVE TROUGHS. BY THURSDAY THE GFS/ECMWF/GEM BRING
THE NEXT SHORTWAVE TROUGH INTO THE NORTHERN PLAINS WHICH IS
PRETTY CONSISTENT WITH THE PAST FEW MODEL RUNS. THE ECMWF/GEM ARE A
BIT MORE ROBUST IN QPF FORECAST FOR NORTH DAKOTA. LIKED THE
ALLBLEND VERSION OF POPS FOR WEDNESDAY NIGHT AT 30 POPS FOR NOW.
AFTER THURSDAY THE FLOW ALOFT BECOMES SEPARATED BETWEEN A NORTHERN
AND SOUTHERN STREAM FLOW WITH THE GFS MORE PRONOUNCED IN THE FLOW
SEPARATION AROUND A CUTOFF LOW OFF THE WEST COAST. THE BASIC
RESULT WILL BE A QUIET PERIOD FRIDAY INTO SATURDAY AS THE FLOW
MERGES ALOFT OVER THE NORTHERN PLAINS RESULTING IN WEAK SUDSIDENCE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1240 AM CDT SUN AUG 31 2014
0530Z A LINE OF THUNDERSTORMS WAS PROGRESSING EAST ALONG A FRONTAL
BOUNDARY OVER CENTRAL NORTH DAKOTA. KMOT-KBIS-KJMS WILL INITIALLY
BE IMPACTED BY THE STORMS. AFTER 08Z THE LINE WILL HAVE MOVED EAST
OF KMOT-KBIS AND THEN AFTER 10Z AT KJMS. NORTHWEST FLOW MAY BRING
IN SOME MVFR CEILINGS ESPECIALLY AFTER SUNRISE CENTRAL AND EAST.
OTHERWISE ONLY VERY ISOLATED SHOWERS DURING THE DAY SUNDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MM
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1039 PM EDT MON SEP 1 2014
.SYNOPSIS...
A COLD FRONT WILL REACH THE NORTHERN OHIO VALLEY BY DAYBREAK AND
CROSS THE REGION FROM THE NORTHWEST ON TUESDAY. HIGH PRESSURE WILL
BRIEFLY BUILD IN BEHIND THE FRONT...WITH DRY CONDITIONS EXPECTED
FOR WEDNESDAY. A RETURN TO SOUTHERLY FLOW WILL INCREASE THE THREAT
FOR SHOWERS AND STORMS AT THE END OF THE WEEK...CULMINATING ON
SATURDAY AS THE NEXT COLD FRONT CROSSES THE REGION.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
ONLY A FEW SHOWERS LINGERING IN THE FAR EASTERN ZONES AND THEY
WILL MOVE OUT BEFORE MIDNIGHT. SHOWERS AND STORMS OCCURRING IN THE
CENTRAL PLAINS WILL SPREAD EAST NORTHEAST TOWARDS THE REGION. HRRR
AND RAP MODELS SHOWING SOME TIMING DISCREPANCIES. BUT IT APPEARS
THAT ACTIVITY WILL NOT SPREAD INTO WESTERN ZONES UNTIL VERY LATE
TONIGHT. EXPECT ANY HEAVIER RAINFALL TO CLOSER TO THE END OF THE
PERIOD AND INTO TUESDAY. FORECAST LOWS LOOK REASONABLE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
BY THE TIME DAYLIGHT HOURS OF TUESDAY ROLLS AROUND...THE SYSTEM IS
EXPECTED TO SHIFT THE SW-NE AXIS MORE INTO THE CWA AND ALONG THE
I-71 CORRIDOR. AREAS THAT SAW EXCESSIVE RAINFALL ON SATURDAY MAY
BE HIT WITH ANOTHER SOAKER...BUT THE UNUSUALLY HIGH VALUES SHOULD
NOT MAKE ANOTHER APPEARANCE...AT LEAST OVER WARREN AND GREENE
COUNTIES. PRECIP DURING THE DAY OVER THE CWA WILL BE PROGRESSIVE
AND EXPAND SOUTHEAST TO COVER THE REST OF CWA BY THE AFTERNOON.
HIGH TEMPS WILL BE MUTED DUE TO THE RAINFALL...GENERALLY IN THE
LOW 80S...SOME MID 80S ARE POSSIBLE IF THE RAIN HOLDS OFF A FEW
HOURS OVER THE SOUTHEAST.
HIGH PRESSURE WILL BRIEFLY FILL IN BEHIND THE COLD FRONT AND
PROVIDE ENOUGH DOWNWARD MOTION TO HELP SCOUR OUT MOST OF THE CLOUD
COVER AND USHER IN SOME DRIER AIR. THE DRIEST AIR AND SUBSEQUENT
COOLER TEMPERATURES FOR TUESDAY NIGHT WILL BE FOUND ALONG AND
NORTH OF THE I-70 CORRIDOR...WITH THE AREA EAST OF COLUMBUS
GETTING THE BEST COOLING BOTH TUES AND WED NIGHTS. NORTH OF DAYTON
ON WED NIGHT WILL LIKELY BE INVOLVED WITH THE RETURNING WARMER AND
MORE MOIST AIR ON THE SOUTHERLY WINDS.
HIGHS ON WEDNESDAY WILL REACH THE LOW TO MID 80S ACROSS THE
REGION.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
PERIOD BEGINS WITH A WEAK WARM FRONT LIFTING UP THROUGH THE WRN OHIO
VALLEY. AS FRONT LIFTS UP ACROSS THE AREA THURSDAY...THERE WILL BE A
SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM.
BY FRIDAY...A CDFNT BEGINS TO PUSH THROUGH THE GREAT LAKES. MODELS
ARE SHOWING A RANGE ON THE FROPA TIMING. THE GFS IS THE
QUICKEST...WHILE THE ECMWF IS ON THE SLOWER END OF THE GUIDANCE.
BOTH MODELS SHOW FROPA FRIDAY NIGHT INTO SATURDAY MORNING WITH
CONTINUED PCPN CHANCES ON SATURDAY. PUT THE BEST POPS FRIDAY NIGHT
WITH 50 POP ACROSS THE REGION. REDEVELOPED THE PCPN SATURDAY MORNING
WITH 50 POPS ACROSS THE SOUTH...BUT LOWER POPS TO THE NW.
THE GFS DRIES THINGS OUT QUICKER SATURDAY NIGHT AS COMPARED TO THE
ECMWF WHICH LEAVES LINGERING PCPN CHANCES INTO SATURDAY NIGHT ACROSS
THE SOUTH. HELD ON TO 20 POPS FOR THE EVENING HOURS IN THE SOUTHEAST.
HIGH PRESSURE BUILDS ACROSS THE REGION SUNDAY INTO MONDAY.
WARM AND HUMID CONDITIONS ARE EXPECTED FOR THURSDAY AND FRIDAY.
HIGHS WILL BE IN THE UPPER 80S TO 90 WITH DEWPOINTS IN THE UPPER 60S
TO LOWER 70S. COOLER CONDITIONS SATURDAY WITH HIGHS RANGING FROM THE
MID 70S IN THE NORTH TO THE LOWER 80S IN NRN KY. BY SUNDAY AND
MONDAY...HIGHS WILL BE IN THE LOWER TO MID 70S ACROSS THE REGION.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
A MID DECK WILL SPREAD INTO THE REGION AFTER 06Z WITH SOME
SHOWERS ASSOCIATED WITH IT. MORE WIDESPREAD SHOWERS AND
THUNDERSTORMS WILL FOLLOW. THERE ARE SOME TIMING DISCREPANCIES IN
THE NEAR TERM GUIDANCE. HAVE USED A SOMEWHAT FASTER SOLUTION WHICH
WOULD BRING THE PRECIPITATION IN BEFORE 12Z. APPEARS THAT HEAVIER
RAINFALL AND THUS BETTER CHANCE OF PREVAILING MVFR CEILINGS AND
VISIBILITIES WILL BE AT KDAY. SHOWERS AND STORMS ARE EXPECTED TO
LAST INTO THE AFTERNOON BEFORE TAPERING OFF/MOVING EAST. WINDS
WILL SHIFT TO A MORE WESTERLY COMPONENT IN THE LATTER PART OF THE
TAF PERIOD.
OUTLOOK...MVFR TO IFR VISIBILITIES ARE POSSIBLE LATE TUESDAY NIGHT
INTO WEDNESDAY MORNING. THUNDERSTORMS POSSIBLE FRIDAY INTO SATURDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...
SHORT TERM...FRANKS
LONG TERM...SITES
AVIATION...
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1116 AM EDT SUN AUG 31 2014
.SYNOPSIS...
DEEP MOISTURE AND UPPER LEVEL DISTURBANCES PROVIDE ROUNDS OF
SHOWERS AND STORMS TODAY. WEAK FRONT CROSSES TUESDAY WITH SHOWERS
AND STORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
SENT A QUICK UPDATE TO ADJUST POPS ACCORDING WITH LATEST DOPPLER
RADAR AND HIGH RESOLUTION MODELS. REMOVED THUNDER AT LEAST THROUGH
18Z AS THERE IS NO SIGN OF LIGHTNING UNDER AREAS OF STRATIFORM
RAIN. EMBEDDED SHOWERS COULD BECOME THUNDERSTORMS THIS AFTERNOON
ACROSS CENTRAL WV. THE HEAVIEST RAINFALL COULD REACH 0.5 INCHES
PER HOURS. WILL KEEP MONITORING THE RAINFALL RATES THROUGH THIS
AFTERNOON.
PREVIOUS DISCUSSION BELOW...
UPDATE...
NOW HAVE EVIDENCE OF THE STRATUS DECK SHOWING UP OVER SOUTHEAST
OHIO AND THE TRI STATE AREA WITH FEW/SCT SHOWING UP IN THE OBS
BELOW 2500FT. REWORKED THE POPS GIVEN THE RADAR TRENDS...AND
CONTINUE WITH THE QUIETER PERIOD BETWEEN 12Z AND 16Z. RAINFALL
AMOUNTS OVER THE LAST 3 HOURS ARE IN THE 0.2 TO 0.3 INCH RANGE IN
THE HEAVIER AMOUNTS.
PREVIOUS DISCUSSION...
THROUGH THE EARLY AFTERNOON/18Z TIME FRAME TODAY...LEANED HEAVILY ON
THE HRRR MODEL GIVEN THAT IT HAD INITIALIZED VERY WELL. TYPICALLY
LIKE THE OUTPUT OF THIS MODEL WHEN THAT HAPPENS. ALSO...SINCE THE
NAM MATCHED UP FAIRLY WELL...DEFORMATION AND FRONTOGENESIS PROGS
PROVED VALUABLE IN THE PATTERN OF THE POP CONSTRUCTION THIS MORNING.
THIS HELPED TO ADD SOME DEFINITION TO THE PREVIOUS
FORECAST...PARTICULARLY OVER THE LOWLANDS SOUTH/EAST OF THE OHIO
RIVER.
AXIS OF DEEP MOISTURE DEPARTS TONIGHT...ALTHOUGH MAY STILL BE
HANGING ON IN THE MOUNTAINS BY 12Z MONDAY.
TEMPERATURES COME DOWN SIGNIFICANTLY FOR TODAY IN THE PERIODIC RAIN.
MAY NOT COME OUT OF THE 70S OVER SOUTHEAST OHIO. SOUTHERN MOUNTAIN
LOCATIONS IN THE EASTERN PORTION OF THE CWA COULD END UP WARMER THAN
THE OHIO RIVER SITES. THE MAV GUIDANCE HAS BEEN HANDS DOWN BETTER
THAN THE OTHERS AND LEANED ON THIS...BUT ALWAYS A LITTLE HESITANT
IN A DIFFERENT ATMOSPHERE.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
MODELS AGREE OUR AREA WILL BE BETWEEN TWO SIGNIFICANT SYSTEMS ON
MONDAY. WHILE DYNAMICS WILL BE AT A MINIMUM...A WARM AND HUMID
AIRMASS WILL CONTINUE FOR A THREAT OF SCATTERED AFTERNOON STORMS
MONDAY...AND MORE SUNSHINE WILL LEAD TO HIGH TEMPERATURES IN THE MID
TO UPPER 80S. WITH LOSS OF HEATING...ANY CONVECTION WILL DISSIPATE
QUICKLY EARLY MONDAY EVENING. IT WILL REMAIN MOSTLY PRECIP FREE
MONDAY NIGHT BEFORE THE NEXT SYSTEM IN THE FORM OF ANOTHER UPPER
TROUGH AND ASSOCIATED COOL FRONT AFFECT US TUESDAY. MODELS HAVE THE
UPPER TROUGH PROGRESSING EASTWARD ACROSS OUR AREA TUESDAY AND EARLY
TUESDAY NIGHT WITH A BAND OF SHOWERS AND STORMS. SO HIGH POPS
PROGRESSING FROM NORTHWEST TO SOUTHEAST TUESDAY INTO EARLY TUESDAY
NIGHT ARE IN ORDER. WHILE THE UPPER TROUGH EXITS TUESDAY NIGHT...THE
COOL FRONT WILL LOSE DEFINITION AS IT CROSSES THE AREA...AND
GRADUALLY BE REPLACED BY WEAK HIGH PRESSURE LATER TUESDAY NIGHT AND
WEDNESDAY. HEIGHTS RISE MODESTLY BEHIND THE UPPER TROUGH...BUT
MODELS STILL INDICATE ENOUGH MOISTURE AND INSTABILITY IN THE FAR
SOUTH FOR A SHOWER OR TWO TO CONTINUE INTO WEDNESDAY. LOOK FOR HIGH
TEMPERATURES TO STAY IN THE 80S FOR TUESDAY AND WEDNESDAY...BUT WITH
SOME DRIER AIR FILTERING INTO THE NORTH TUESDAY NIGHT AND
WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LONG TERM PERIOD CAN GENERALLY BE CHARACTERIZED BY ZONAL FLOW ALOFT.
LEANED WPC FOR THE MOST PART WITH A FEW TWEAKS HERE AND THERE. WARM
AND MUGGY CONDITIONS WILL CONTINUE THROUGH THE PERIOD...WITH NO HEAT
WAVES OR ABNORMALLY COOL SPELLS IN SIGHT. A COLD FRONT WILL PUSH
ACROSS TUE NIGHT WITH ANOTHER FRONT APPROACHING SAT NIGHT...WITH
SUBSEQUENT HIGHER POPS DURING THOSE PERIODS. IN BETWEEN...THURSDAY
AND FRIDAY LOOK MOSTLY SUNNY TO PERHAPS PARTLY CLOUDY WITH ONLY
MINIMAL CHANCES FOR PRECIP EACH DAY.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL ACROSS MOST SITES THROUGH 18Z. THE
EXCEPTION WILL BE MVFR UNDER LIGHT RAIN POSSIBLE AT HTS...TO MOVE
OVER CRW BY 18-20Z. CONVECTION WILL INCREASE IN INTENSITY ACROSS
CENTRAL WV THIS AFTERNOON.
INCLUDED TSRA FOR CRW...CKB...AND BKW...AND VCTS/CB FOR THE REST
OF SITES AFTER 18Z.
EXPECT AND EXTENSIVE LOW STRATUS DECK TO SET UP THIS EVENING AS
THE DEEPER MOISTURE PUSHES NORTHEASTWARD. AS THOSE CEILINGS COME
DOWN...FEEL THE VISIBILITIES CAN COME DOWN AS WELL WITH THE RECENT
RAIN. NO LIFR FOG DUE TO LIGHT WINDS OVERNIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING AND EXTENT OF TSRA THIS AFTERNOON MAY
VARY. EXTEND OF POST RAIN AND SUBSIDENCE OF LOW STRATUS COULD VARY
FROM SITE TO SITE.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H M M M M M M M M M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H M M
PKB CONSISTENCY M H H H H H H H M M M M
CKB CONSISTENCY M H H H H H M M M M M M
AFTER 12Z MONDAY...
IFR IN DENSE EARLY MORNING VALLEY FOG EARLY NEXT WEEK. IFR IN
SHOWERS AND STORMS POSSIBLE WITH THE COLD FRONT TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...ARJ/26
SHORT TERM...JMV
LONG TERM...50
AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
640 AM EDT SUN AUG 31 2014
.SYNOPSIS...
DEEP MOISTURE AND UPPER LEVEL DISTURBANCES PROVIDE ROUNDS OF
SHOWERS AND STORMS TODAY. WEAK FRONT CROSSES TUESDAY WITH SHOWERS
AND STORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
NOW HAVE EVIDENCE OF THE STRATUS DECK SHOWING UP OVER SOUTHEAST
OHIO AND THE TRI STATE AREA WITH FEW/SCT SHOWING UP IN THE OBS
BELOW 2500FT. REWORKED THE POPS GIVEN THE RADAR TRENDS...AND
CONTINUE WITH THE QUIETER PERIOD BETWEEN 12Z AND 16Z. RAINFALL
AMOUNTS OVER THE LAST 3 HOURS ARE IN THE 0.2 TO 0.3 INCH RANGE IN
THE HEAVIER AMOUNTS.
PREVIOUS DISCUSSION...
THROUGH THE EARLY AFTERNOON/18Z TIME FRAME TODAY...LEANED HEAVILY ON
THE HRRR MODEL GIVEN THAT IT HAD INITIALIZED VERY WELL. TYPICALLY
LIKE THE OUTPUT OF THIS MODEL WHEN THAT HAPPENS. ALSO...SINCE THE
NAM MATCHED UP FAIRLY WELL...DEFORMATION AND FRONTOGENESIS PROGS
PROVED VALUABLE IN THE PATTERN OF THE POP CONSTRUCTION THIS MORNING.
THIS HELPED TO ADD SOME DEFINITION TO THE PREVIOUS
FORECAST...PARTICULARLY OVER THE LOWLANDS SOUTH/EAST OF THE OHIO
RIVER.
AXIS OF DEEP MOISTURE DEPARTS TONIGHT...ALTHOUGH MAY STILL BE
HANGING ON IN THE MOUNTAINS BY 12Z MONDAY.
TEMPERATURES COME DOWN SIGNIFICANTLY FOR TODAY IN THE PERIODIC RAIN.
MAY NOT COME OUT OF THE 70S OVER SOUTHEAST OHIO. SOUTHERN MOUNTAIN
LOCATIONS IN THE EASTERN PORTION OF THE CWA COULD END UP WARMER THAN
THE OHIO RIVER SITES. THE MAV GUIDANCE HAS BEEN HANDS DOWN BETTER
THAN THE OTHERS AND LEANED ON THIS...BUT ALWAYS A LITTLE HESITANT
IN A DIFFERENT ATMOSPHERE.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
MODELS AGREE OUR AREA WILL BE BETWEEN TWO SIGNIFICANT SYSTEMS ON
MONDAY. WHILE DYNAMICS WILL BE AT A MINIMUM...A WARM AND HUMID
AIRMASS WILL CONTINUE FOR A THREAT OF SCATTERED AFTERNOON STORMS
MONDAY...AND MORE SUNSHINE WILL LEAD TO HIGH TEMPERATURES IN THE MID
TO UPPER 80S. WITH LOSS OF HEATING...ANY CONVECTION WILL DISSIPATE
QUICKLY EARLY MONDAY EVENING. IT WILL REMAIN MOSTLY PRECIP FREE
MONDAY NIGHT BEFORE THE NEXT SYSTEM IN THE FORM OF ANOTHER UPPER
TROUGH AND ASSOCIATED COOL FRONT AFFECT US TUESDAY. MODELS HAVE THE
UPPER TROUGH PROGRESSING EASTWARD ACROSS OUR AREA TUESDAY AND EARLY
TUESDAY NIGHT WITH A BAND OF SHOWERS AND STORMS. SO HIGH POPS
PROGRESSING FROM NORTHWEST TO SOUTHEAST TUESDAY INTO EARLY TUESDAY
NIGHT ARE IN ORDER. WHILE THE UPPER TROUGH EXITS TUESDAY NIGHT...THE
COOL FRONT WILL LOSE DEFINITION AS IT CROSSES THE AREA...AND
GRADUALLY BE REPLACED BY WEAK HIGH PRESSURE LATER TUESDAY NIGHT AND
WEDNESDAY. HEIGHTS RISE MODESTLY BEHIND THE UPPER TROUGH...BUT
MODELS STILL INDICATE ENOUGH MOISTURE AND INSTABILITY IN THE FAR
SOUTH FOR A SHOWER OR TWO TO CONTINUE INTO WEDNESDAY. LOOK FOR HIGH
TEMPERATURES TO STAY IN THE 80S FOR TUESDAY AND WEDNESDAY...BUT WITH
SOME DRIER AIR FILTERING INTO THE NORTH TUESDAY NIGHT AND
WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LONG TERM PERIOD CAN GENERALLY BE CHARACTERIZED BY ZONAL FLOW ALOFT.
LEANED WPC FOR THE MOST PART WITH A FEW TWEAKS HERE AND THERE. WARM
AND MUGGY CONDITIONS WILL CONTINUE THROUGH THE PERIOD...WITH NO HEAT
WAVES OR ABNORMALLY COOL SPELLS IN SIGHT. A COLD FRONT WILL PUSH
ACROSS TUE NIGHT WITH ANOTHER FRONT APPROACHING SAT NIGHT...WITH
SUBSEQUENT HIGHER POPS DURING THOSE PERIODS. IN BETWEEN...THURSDAY
AND FRIDAY LOOK MOSTLY SUNNY TO PERHAPS PARTLY CLOUDY WITH ONLY
MINIMAL CHANCES FOR PRECIP EACH DAY.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
NOW SEEING THE DEVELOPMENT OF THE EXPECTED MVFR/IFR STRATUS DECK
BACK IN OHIO TOWARDS THE NORTHERN PANHANDLE. WILL BE WATCHING UNI
AND THEN THE RIVER TERMINALS OF PKB AND HTS TO DO THE SAME AND
CARRY THIS IN THE TAFS THIS MORNING.
AFTER A LULL IN THE CONVECTION THIS MORNING...EXPECT IT TO PICK UP
THIS AFTERNOON. CARRYING VCTS/CB IN THE TAFS RIGHT NOW AS THE
BANDS OF SHOWERS AND STORMS PASS THROUGH THE AREA. BEST CHANCE FOR
THE CONVECTION IS WEST OF THE MOUNTAINS AND IN THE OHIO VALLEY.
THIS DOES NOT MEAN THUNDER CHANCES ARE RELEGATED TO THESE AREAS
HOWEVER.
EXPECT AND EXTENSIVE LOW STRATUS DECK TO SET UP THIS EVENING AS
THE DEEPER MOISTURE PUSHES NORTHEASTWARD. AS THOSE CEILINGS COME
DOWN...FEEL THE VISIBILITIES CAN COME DOWN AS WELL WITH THE RECENT
RAIN. NO LIFR FOG DUE TO LIGHT WINDS OVERNIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING AND EXTENT OF TSRA IS IN QUESTION.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY L L L M H H H M M M H M
HTS CONSISTENCY L L L M H M M M M M M M
BKW CONSISTENCY M M M H H H H H H H H H
EKN CONSISTENCY L L L M H H H H H H H H
PKB CONSISTENCY L L L L M M H H H H H M
CKB CONSISTENCY L L L L M M H H H M M M
AFTER 12Z MONDAY...
IFR IN DENSE EARLY MORNING VALLEY FOG EARLY NEXT WEEK. IFR IN
SHOWERS AND STORMS POSSIBLE WITH THE COLD FRONT TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...50
AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
329 AM EDT SUN AUG 31 2014
.SYNOPSIS...
DEEP MOISTURE AND UPPER LEVEL DISTURBANCES PROVIDE ROUNDS OF
SHOWERS AND STORMS TODAY. WEAK FRONT CROSSES TUESDAY WITH SHOWERS
AND STORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
THROUGH THE EARLY AFTERNOON/18Z TIME FRAME TODAY...LEANED HEAVILY ON
THE HRRR MODEL GIVEN THAT IT HAD INITIALIZED VERY WELL. TYPICALLY
LIKE THE OUTPUT OF THIS MODEL WHEN THAT HAPPENS. ALSO...SINCE THE
NAM MATCHED UP FAIRLY WELL...DEFORMATION AND FRONTOGENESIS PROGS
PROVED VALUABLE IN THE PATTERN OF THE POP CONSTRUCTION THIS MORNING.
THIS HELPED TO ADD SOME DEFINITION TO THE PREVIOUS
FORECAST...PARTICULARLY OVER THE LOWLANDS SOUTH/EAST OF THE OHIO
RIVER.
AXIS OF DEEP MOISTURE DEPARTS TONIGHT...ALTHOUGH MAY STILL BE
HANGING ON IN THE MOUNTAINS BY 12Z MONDAY.
TEMPERATURES COME DOWN SIGNIFICANTLY FOR TODAY IN THE PERIODIC RAIN.
MAY NOT COME OUT OF THE 70S OVER SOUTHEAST OHIO. SOUTHERN MOUNTAIN
LOCATIONS IN THE EASTERN PORTION OF THE CWA COULD END UP WARMER THAN
THE OHIO RIVER SITES. THE MAV GUIDANCE HAS BEEN HANDS DOWN BETTER
THAN THE OTHERS AND LEANED ON THIS...BUT ALWAYS A LITTLE HESITANT
IN A DIFFERENT ATMOSPHERE.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
MODELS AGREE OUR AREA WILL BE BETWEEN TWO SIGNIFICANT SYSTEMS ON
MONDAY. WHILE DYNAMICS WILL BE AT A MINIMUM...A WARM AND HUMID
AIRMASS WILL CONTINUE FOR A THREAT OF SCATTERED AFTERNOON STORMS
MONDAY...AND MORE SUNSHINE WILL LEAD TO HIGH TEMPERATURES IN THE MID
TO UPPER 80S. WITH LOSS OF HEATING...ANY CONVECTION WILL DISSIPATE
QUICKLY EARLY MONDAY EVENING. IT WILL REMAIN MOSTLY PRECIP FREE
MONDAY NIGHT BEFORE THE NEXT SYSTEM IN THE FORM OF ANOTHER UPPER
TROUGH AND ASSOCIATED COOL FRONT AFFECT US TUESDAY. MODELS HAVE THE
UPPER TROUGH PROGRESSING EASTWARD ACROSS OUR AREA TUESDAY AND EARLY
TUESDAY NIGHT WITH A BAND OF SHOWERS AND STORMS. SO HIGH POPS
PROGRESSING FROM NORTHWEST TO SOUTHEAST TUESDAY INTO EARLY TUESDAY
NIGHT ARE IN ORDER. WHILE THE UPPER TROUGH EXITS TUESDAY NIGHT...THE
COOL FRONT WILL LOSE DEFINITION AS IT CROSSES THE AREA...AND
GRADUALLY BE REPLACED BY WEAK HIGH PRESSURE LATER TUESDAY NIGHT AND
WEDNESDAY. HEIGHTS RISE MODESTLY BEHIND THE UPPER TROUGH...BUT
MODELS STILL INDICATE ENOUGH MOISTURE AND INSTABILITY IN THE FAR
SOUTH FOR A SHOWER OR TWO TO CONTINUE INTO WEDNESDAY. LOOK FOR HIGH
TEMPERATURES TO STAY IN THE 80S FOR TUESDAY AND WEDNESDAY...BUT WITH
SOME DRIER AIR FILTERING INTO THE NORTH TUESDAY NIGHT AND
WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LONG TERM PERIOD CAN GENERALLY BE CHARACTERIZED BY ZONAL FLOW ALOFT.
LEANED WPC FOR THE MOST PART WITH A FEW TWEAKS HERE AND THERE. WARM
AND MUGGY CONDITIONS WILL CONTINUE THROUGH THE PERIOD...WITH NO HEAT
WAVES OR ABNORMALLY COOL SPELLS IN SIGHT. A COLD FRONT WILL PUSH
ACROSS TUE NIGHT WITH ANOTHER FRONT APPROACHING SAT NIGHT...WITH
SUBSEQUENT HIGHER POPS DURING THOSE PERIODS. IN BETWEEN...THURSDAY
AND FRIDAY LOOK MOSTLY SUNNY TO PERHAPS PARTLY CLOUDY WITH ONLY
MINIMAL CHANCES FOR PRECIP EACH DAY.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
VERY COMPLEX TAFS TODAY GIVEN THE UNSETTLED SURFACE AND UPPER
LEVEL CONDITIONS BRINGING SHOWERS WITH A FEW EMBEDDED STORMS
THROUGH THE PERIOD.
TRIED TO USE AS MUCH PREVAILING SHRA AS POSSIBLE...AND ALSO TRIED
TO PEG THE BEST CHANCES FOR TSRA WITH PEAK HEATING TODAY UTILIZING
THE PROB30 WORDING IN THE TAFS. THIS TIMING HAS A LOWER CONFIDENCE
ATTACHED TO IT.
AFTER THE INITIAL WAVE OF RAIN EXITS THE OHIO VALLEY...EXPECT AN
MVFR STRATUS LAYER TO DEVELOP TOWARDS DAWN. THIS COULD LIMIT
THUNDER CHANCES UNTIL THIS LAYER DISSOLVES...AND WILL MAINLY AFFECT
PKB AND HTS.
LATER TONIGHT...AS THE CEILINGS LOWER AGAIN AFTER THE MAIN BATCH
OF RAIN MOVES INTO THE MOUNTAINS...EXPECT CEILINGS TO LOWER. AS
THIS HAPPENS THE CHANCES FOR VISIBILITIES TO LOWER INCREASE AS
WELL.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING AND EXTENT OF TSRA IS IN QUESTION.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SUN 08/31/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15
CRW CONSISTENCY M M L L L L M H H H H H
HTS CONSISTENCY M M M L L L M M M H H M
BKW CONSISTENCY M M M M M M M H H H H H
EKN CONSISTENCY L L L L L L M H H H H H
PKB CONSISTENCY M M M L L L L L L H H H
CKB CONSISTENCY M M M L L L L L L M H H
AFTER 06Z MONDAY...
IFR IN DENSE EARLY MORNING VALLEY FOG EARLY NEXT WEEK.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...50
AVIATION...26
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
158 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A WEAK COLD FRONT OVER THE GREAT LAKES WILL BECOME STATIONARY ON
SUNDAY JUST NORTH OF LAKE ERIE. AN AREA OF LOW PRESSURE OVER THE
GULF COAST STATES WILL MOVE NORTHEAST UP THE APPALACHIANS
OVERNIGHT AND SUNDAY. A STRONGER COLD FRONT WILL MOVE FROM THE
NORTHERN PLAINS AND CROSS THE AREA ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
BAND OF SHOWERS CONTINUE TO MOVE NORTHEAST ACROSS THE EASTERN
PORTIONS OF THE FORECAST AREA IN ASSOCIATION WITH UPPER LEVEL
POSITIVE VORTICITY ADVECTION. MORE ACTIVE ACTIVITY ACROSS SOUTHERN
OHIO SHOULD LIFT NORTHEAST INTO THE REGION OVERNIGHT BUT SHOULD
ALSO WEAKEN TO JUST SHOWERS. FURTHER WEST...A LINE OF SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO ADVANCE EAST WITH THE COLD FRONT.
LATEST HRRR GUIDANCE SUGGESTS LINE WILL WEAKEN BY THE TIME IT
REACHES OUR AREA. THIS SEEMS LOGICAL SINCE THERE IS A LOT OF CIN
OVER THE REGION AT THIS TIME TO OVERCOME.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
A WARM...MUGGY AND UNSETTLED AIR MASS WILL LINGER OVER THE AREA
MOST OF THE PERIOD. UNSEASONABLY WARM SURFACE DEW POINTS WILL MAKE
IT FEEL MORE LIKE JULY THAN LABOR DAY WEEKEND. MODELS CONTINUE TO
HAVE DIFFICULTY PIN POINTING PRECIP CHANCES. IT DOES APPEAR THAT
BEST CHANCES FOR PRECIP ON SUNDAY WILL BE ACROSS THE SOUTHEAST
HALF OF THE AREA. FURTHER NORTH WEAK HIGH PRESSURE WILL BRIEFLY
BUILD OVER LAKE ERIE IN THE WAKE OF THE SURFACE LOW MOVING THROUGH
NOW. BY SUNDAY EVENING THE THREAT FOR PRECIP SHOULD BE OVER ALL
AREAS. ANOTHER LOW OVER THE PLAINS WILL LIFT A WARM FRONT BACK
ACROSS THE AREA ON MONDAY. THE MODELS ARE IN A LITTLE BIT BETTER
AGREEMENT WITH THIS SYSTEM. WILL NEED ANOTHER PERIOD OF LIKELY OR
HIGHER WORDING FROM LATE MONDAY TILL A COLD FRONT CROSSES THE
REGION ON TUESDAY. PRECIP CHANCES WILL DIMINISH BY TUESDAY
EVENING. THE FRONTAL PASSAGE WON`T BE STRONG ENOUGH TO BRING A
COMPLETE AIR MASS CHANGE BUT SURFACE DEW POINTS SHOULD DIP INTO THE
LOWER 60S.
SUNDAY WILL BE THE COOLEST DAY OF THE PERIOD WITH THE PRECIP
ACROSS THE AREA. THE REMAINDER OF THE PERIOD WILL BE ABOVE NORMAL
AND HAVE USED A BLEND OF GUIDANCE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
UPPER RIDGE BUILDS IN FROM THE SOUTH BEHIND EXITING TROUGH ON
WEDNESDAY. WITH INFLUENCE OF THE RIDGE IN WEAK FLOW PATTER MOST
CONVECTION WILL BE SUPPRESSED. CAN`T COMPLETELY RULE OUT TSRA
BUT FOR NOW WILL KEEP A SMALL POP IN THROUGH FRIDAY. THE MODELS ARE
IN FAIRLY STRONG AGREEMENT THAT THE RIDGE WILL LEAD TO H850 TEMPS
18-20C FOR LATE IN THE WEEK. THIS MAKES IT DIFFICULT TO LEAN TOWARDS
THE MUCH COOLER CLIMATOLOGY (UPPER 70S) FOR THU-SAT...SO HAVE
TRENDED CLOSER TO THE MODEL GUIDANCE MID 80S. THE MOISTURE ADVECTION
IS NOT AS FAVORABLE AS IT WAS WITH THE CURRENT WEATHER PATTERN...SO
DESPITE HIGH SFC DEW POINTS THE OVERALL PRECIPITABLE WATER VALUES
FOR THE AIR COLUMN WILL BE LOWER IN THE 1.5" RANGE. THIS WILL AGAIN
SUPPORT A LOWER CHANCE FOR PRECIPITATION. THE TIMING ON THE FRONT
WHICH WILL BRING THE WARM WEATHER TO AN END IS LOOKING MORE LIKE
LATE SATURDAY WHICH SHOULD BRING BETTER CHANCES OF THUNDERSTORMS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THE FLOW IS SOUTHWEST AHEAD OF THE COLD FRONT THAT IS WELL NORTH
OF LAKE ERIE. THE FRONT WILL REMAIN WELL NORTH OF THE AREA THROUGH
THE TAF PERIOD. HOWEVER...PLENTY OF MOISTURE IN THIS FLOW WILL CAUSE
MAINLY SHOWERS AT THE TAF SITES THROUGH EARLY AFTERNOON AND THEN A
DECREASE IN SHOWERS. SOME THUNDERSTORMS ARE POSSIBLE. THE
THUNDERSTORMS OVER CENTRAL INDIANA ARE EXPECTED TO DECREASE.
VFR CONDITIONS TO START AND THEN MVFR CEILINGS WILL DEVELOP BY
DAYBREAK ALONG WITH SOME MVFR VISIBILITIES. PLENTY OF LOW LEVEL
MOISTURE SO SOME IFR CEILINGS ARE ALSO POSSIBLE MAINLY BETWEEN
DAYBREAK AND EARLY AFTERNOON. CONFIDENCE IS AROUND 60% THAT SOME
IFR CEILINGS WILL DEVELOP.
OUTLOOK...NON VFR LIKELY AT TIMES IN SHOWERS AND THUNDERSTORMS
THROUGH TUESDAY.
&&
.MARINE...
LOW LEVEL JET WILL STRENGTHEN AS AN AREA OF LOW PRESSURE ADVANCED
TOWARDS LAKE ERIE THIS EVENING. LOOK FOR WINDS AROUND 20KT WITH
GUSTS AROUND 25 KT OVERNIGHT. THE SW DIRECTION WILL KEEP THE LARGEST
WAVES OFFSHORE OR IN CANADIAN WATERS. COULD STILL SEE SOME 4 FOOTERS
IN THE NEAR SHORE. ENERGY WILL SLIDE EAST SUNDAY MORNING AND THOUGH
WINDS ARE STILL SW THE SPEEDS WILL DROP OFF NOTABLY. THE NEXT
FRONTAL BOUNDARY WILL COME THROUGH MONDAY NIGHT AT WHICH TIME THE
WINDS COULD ONCE AGAIN REACH SMALL CRAFT. HIGH PRESSURE WILL BUILD
BACK IN AND WINDS/WAVES WILL REMAIN BELOW HEADLINE CRITERIA THE REST
OF THE FORECAST PERIODS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR LEZ148-
149.
&&
$$
SYNOPSIS...KOSARIK
NEAR TERM...LOMBARDY
SHORT TERM...KUBINA
LONG TERM...JAMISON
AVIATION...KIELTYKA
MARINE...JAMISON
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1233 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A WEAK COLD FRONT OVER THE GREAT LAKES WILL BECOME STATIONARY ON
SUNDAY JUST NORTH OF LAKE ERIE. AN AREA OF LOW PRESSURE OVER THE
GULF COAST STATES WILL MOVE NORTHEAST UP THE APPALACHIANS
OVERNIGHT AND SUNDAY. A STRONGER COLD FRONT WILL MOVE FROM THE
NORTHERN PLAINS AND CROSS THE AREA ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
BAND OF SHOWERS CONTINUE TO MOVE NORTHEAST ACROSS THE EASTERN
PORTIONS OF THE FORECAST AREA IN ASSOCIATION WITH UPPER LEVEL
POSITIVE VORTICITY ADVECTION. MORE ACTIVE ACTIVITY ACROSS SOUTHERN
OHIO SHOULD LIFT NORTHEAST INTO THE REGION OVERNIGHT BUT SHOULD
ALSO WEAKEN TO JUST SHOWERS. FURTHER WEST...A LINE OF SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO ADVANCE EAST WITH THE COLD FRONT.
LATEST HRRR GUIDANCE SUGGESTS LINE WILL WEAKEN BY THE TIME IT
REACHES OUR AREA. THIS SEEMS LOGICAL SINCE THERE IS A LOT OF CIN
OVER THE REGION AT THIS TIME TO OVERCOME.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
A WARM...MUGGY AND UNSETTLED AIR MASS WILL LINGER OVER THE AREA
MOST OF THE PERIOD. UNSEASONABLY WARM SURFACE DEW POINTS WILL MAKE
IT FEEL MORE LIKE JULY THAN LABOR DAY WEEKEND. MODELS CONTINUE TO
HAVE DIFFICULTY PIN POINTING PRECIP CHANCES. IT DOES APPEAR THAT
BEST CHANCES FOR PRECIP ON SUNDAY WILL BE ACROSS THE SOUTHEAST
HALF OF THE AREA. FURTHER NORTH WEAK HIGH PRESSURE WILL BRIEFLY
BUILD OVER LAKE ERIE IN THE WAKE OF THE SURFACE LOW MOVING THROUGH
NOW. BY SUNDAY EVENING THE THREAT FOR PRECIP SHOULD BE OVER ALL
AREAS. ANOTHER LOW OVER THE PLAINS WILL LIFT A WARM FRONT BACK
ACROSS THE AREA ON MONDAY. THE MODELS ARE IN A LITTLE BIT BETTER
AGREEMENT WITH THIS SYSTEM. WILL NEED ANOTHER PERIOD OF LIKELY OR
HIGHER WORDING FROM LATE MONDAY TILL A COLD FRONT CROSSES THE
REGION ON TUESDAY. PRECIP CHANCES WILL DIMINISH BY TUESDAY
EVENING. THE FRONTAL PASSAGE WON`T BE STRONG ENOUGH TO BRING A
COMPLETE AIR MASS CHANGE BUT SURFACE DEW POINTS SHOULD DIP INTO THE
LOWER 60S.
SUNDAY WILL BE THE COOLEST DAY OF THE PERIOD WITH THE PRECIP
ACROSS THE AREA. THE REMAINDER OF THE PERIOD WILL BE ABOVE NORMAL
AND HAVE USED A BLEND OF GUIDANCE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
UPPER RIDGE BUILDS IN FROM THE SOUTH BEHIND EXITING TROUGH ON
WEDNESDAY. WITH INFLUENCE OF THE RIDGE IN WEAK FLOW PATTER MOST
CONVECTION WILL BE SUPPRESSED. CAN`T COMPLETELY RULE OUT TSRA
BUT FOR NOW WILL KEEP A SMALL POP IN THROUGH FRIDAY. THE MODELS ARE
IN FAIRLY STRONG AGREEMENT THAT THE RIDGE WILL LEAD TO H850 TEMPS
18-20C FOR LATE IN THE WEEK. THIS MAKES IT DIFFICULT TO LEAN TOWARDS
THE MUCH COOLER CLIMATOLOGY (UPPER 70S) FOR THU-SAT...SO HAVE
TRENDED CLOSER TO THE MODEL GUIDANCE MID 80S. THE MOISTURE ADVECTION
IS NOT AS FAVORABLE AS IT WAS WITH THE CURRENT WEATHER PATTERN...SO
DESPITE HIGH SFC DEW POINTS THE OVERALL PRECIPITABLE WATER VALUES
FOR THE AIR COLUMN WILL BE LOWER IN THE 1.5" RANGE. THIS WILL AGAIN
SUPPORT A LOWER CHANCE FOR PRECIPITATION. THE TIMING ON THE FRONT
WHICH WILL BRING THE WARM WEATHER TO AN END IS LOOKING MORE LIKE
LATE SATURDAY WHICH SHOULD BRING BETTER CHANCES OF THUNDERSTORMS.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
LOW PRESSURE SYSTEM OVER NORTHERN MICHIGAN WITH COLD FRONT INTO
SOUTHERN PLAINS. SWATH OF SHOWERS WITH A FEW EMBEDDED TSRA NOW
INTO SW OHIO WILL WILL MOVE ACROSS THE SOUTHERN AND EASTERN
LOCATIONS THIS EVENING. MODELS HINT AT ANOTHER WAVE OF PRECIP OVER
THE SOUTHERN AND EASTERN TERMINALS TOMORROW MORNING. FRONT WILL
APPROACH NW OHIO TONIGHT THEN BECOME DIFFUSE...SO COULD SEE SOME
TSRA NW OHIO LATER THIS EVENING. JUST WENT WITH TSVC IN TAFS.
OUTLOOK...NON VFR LIKELY IN SHOWERS AND THUNDERSTORMS THROUGH
TUESDAY AT TIMES.
&&
.MARINE...
LOW LEVEL JET WILL STRENGTHEN AS AN AREA OF LOW PRESSURE ADVANCED
TOWARDS LAKE ERIE THIS EVENING. LOOK FOR WINDS AROUND 20KT WITH
GUSTS AROUND 25 KT OVERNIGHT. THE SW DIRECTION WILL KEEP THE LARGEST
WAVES OFFSHORE OR IN CANADIAN WATERS. COULD STILL SEE SOME 4 FOOTERS
IN THE NEAR SHORE. ENERGY WILL SLIDE EAST SUNDAY MORNING AND THOUGH
WINDS ARE STILL SW THE SPEEDS WILL DROP OFF NOTABLY. THE NEXT
FRONTAL BOUNDARY WILL COME THROUGH MONDAY NIGHT AT WHICH TIME THE
WINDS COULD ONCE AGAIN REACH SMALL CRAFT. HIGH PRESSURE WILL BUILD
BACK IN AND WINDS/WAVES WILL REMAIN BELOW HEADLINE CRITERIA THE REST
OF THE FORECAST PERIODS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM EARLY THIS MORNING TO 4 PM EDT
THIS AFTERNOON FOR LEZ148-149.
&&
$$
SYNOPSIS...KOSARIK
NEAR TERM...LOMBARDY
SHORT TERM...KUBINA
LONG TERM...JAMISON
AVIATION...DJB
MARINE...JAMISON
AREA FORECAST DISCUSSION
NWS TULSA OK
618 PM CDT MON SEP 1 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 0Z TAFS... SCATTERED SHOWERS AND THUNDERSTORMS WILL
LIKELY AFFECT NORTHEAST OKLAHOMA AND NORTHWEST ARKASNAS SITES THIS
EVENING. SOME STORMS COULD BE SEVERE WITH LARGE HAIL AND HIGH
WINDS. TEMPORARY MVFR CONDITIONS COULD BE EXPERIENCED WITH ANY
THUNDERSTORM ACTIVITY.
&&
.PREV DISCUSSION... /ISSUED 329 PM CDT MON SEP 1 2014/
DISCUSSION...
A PROGRESSIVE...LOW AMPLITUDE SHORTWAVE TROUGH IS SLIDING EAST
ACROSS THE NORTH CENTRAL PART OF THE COUNTRY TODAY. A PAIR OF
EMBEDDED VORTICITY MAXIMA EXIST...ONE LIFTING QUICKLY NORTHEAST
INTO THE GREAT LAKES...AND ANOTHER MOVING ACROSS WY ATTM.
NORTHEAST OK/NORTHWEST AR LIES ON THE SOUTHERN FRINGE OF THE
DECENT WESTERLY FLOW IN THE MID LEVELS. AT THE SURFACE...A MORE
COMPLEX PATTERN EXISTS DUE TO OVERNIGHT CONVECTION THAT WAS MORE
EXTENSIVE THAN FORECAST. THE OUTFLOW BOUNDARY FROM THAT CONVECTION
HAS BEEN RETREATING NORTH DURING THE AFTERNOON AND IS
APPROACHING THE KANSAS BORDER. MEANWHILE...THE SYNOPTIC COLD FRONT
HAS BECOME NEARLY STATIONARY ACROSS CENTRAL AND SW KS. THE HRRR
HAS BEEN CONSISTENT ALL DAY IN DVLPNG STORMS BTWN 22-00Z IN THE
ZONE BTWN THE TWO BOUNDARIES. DIRECTIONAL/SPEED SHEAR SHOULD BE
GREAT ENOUGH TO SUPPORT SUPERCELLS...ESPECIALLY GIVEN AVAILABLE
CAPE. LOW LEVEL BACKED WINDS IN BTWN THE TWO BOUNDARIES
SUGGESTS...IF A SUPERCELL CAN GET GOING...THAT A LARGE HAIL/TORNADO
RISK EXISTS BEFORE CELLS GRADUALLY CONGEAL INTO CLUSTERS AND THEN
MOVE E/SE THIS EVENING...WHEN THE MAIN THREAT BECOMES DAMAGING
WINDS. MORE DEVELOPMENT IS FORECAST BY THE HRRR LATER TONIGHT
NORTH OF THE EFFECTIVE BOUNDARY. THERE WILL BE A SHARP CUTOFF AS
YOU GO SOUTH WHERE RAIN FALLS AND WHERE IT DOESN`T...GIVEN STRONG
CAP IN PLACE DUE TO EML.
I BACKED OFF SOME ON LOWS TONIGHT ACROSS THE NE OK AND NW AR GIVEN
POTENTIAL FOR CONVECTIVELY COOLED OUTFLOW...MUCH LIKE LAST NIGHT.
RAIN/STORM CHANCES WILL CONTINUE INTO TUESDAY MAINLY ACROSS NE
OK/NW AR NEAR AND NORTH OF THE EFFECTIVE BOUNDARY...WHICH WILL
BEGIN TO RETREAT AGAIN TOMORROW AND ESPECIALLY TOMORROW NIGHT. THE
BEST CHANCES FOR RAIN/STORMS TUESDAY NIGHT WILL BE NORTH AND EAST
OF TULSA IN THE WARM ADVECTION REGIME. PRECIP CHANCES COME TO AN
END WEDNESDAY AS THE BOUNDARY LIFTS NORTH OF THE REGION AND MID
LEVEL HEIGHTS RISE. GUSTY SOUTHWEST WINDS WILL PUSH TEMPS BACK
INTO THE UPPER 90S WEDNESDAY AFTERNOON ACROSS NE OK.
THE DETERMINISTIC RUNS OF THE GFS/ECMWF TODAY ARE SLOWER WITH THE
FRONT TOWARD THE END OF THE WEEK...GFS MORE SO THAN THE ECMWF.
NEVERTHELESS...POPS WILL BE CARRIED FRIDAY AND
SATURDAY...GRADUALLY TAPERING OFF SUNDAY. TEMPS WILL FALL BACK
INTO THE 80S FOR HIGHS AND 60S FOR LOWS.
THE RATHER ACTIVE PATTERN ACROSS THE NORTHERN TIER OF STATES
CONTINUES INTO NEXT WEEK...AS ANOTHER STRONG SYSTEM MOVES ACROSS
THE NORTHERN PART OF THE COUNTRY. AN EVEN STRONGER FRONT COULD BE
ON THE WAY IN ABOUT 10 DAYS...A SIGN OF THE CHANGE IN SEASONS.
LACY
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...06
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
655 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A WARM AND HUMID SOUTHWEST FLOW WILL KEEP THE CHANCES FOR RAIN IN
THE FORECAST THROUGH THE LABOR DAY HOLIDAY. A COLD FRONT WILL
BRING A BREAK IN THE HUMIDITY FOR MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE RADAR BECOMING MORE ACTIVE WITH SCATTERED SHOWERS AND
THUNDERSTORMS MOVING THROUGH WRN PA...MAKING SLOW PROGRESS TOWARD
MY FCST AREA.
THE HRRR SHOWS THE RAIN CURRENTLY FROM KENTUCKY INTO SOUTHERN OHIO
CONTINUING TO MARCH NORTHEAST THROUGH MORNING WITH MOST OF MY
WESTERN ZONES GETTING WET BY ABOUT 6-7AM...AND MUCH OF THE REST OF
MY FCST AREA COVERED WITH SHOWERS AND THUNDERSTORMS BY MID DAY.
THIS AFTERNOON WE COULD ALSO SEE A SEVERE THREAT DEVELOP FOR MY
SERN ZONES. MODELS ARE COOKING UP A FAIR AMOUNT OF CAPE OVER
EASTERN AREAS HINTING THAT THE THE CLOUDS WILL BE LESS EXTENSIVE
ALLOWING FOR MORE IN THE WAY OF SOLAR HEATING. FORECAST MID LEVEL
LAPSE RATES ARE WEAK BUT SHEAR WILL INCREASE WHICH COULD AID IN
ORGANIZING STORM DEVELOPMENT.
MODELS ALSO PROG A WEAK LOW LEVEL CONVERGENCE ZONE...PERHAPS THE
REMNANTS OF THE OLD WARM FRONT WHERE ENHANCED LOW LEVEL
SHEAR...EHI`S PROGGED 1-3(M^2/S^2) COULD HELP A STORM OR TWO TAKE
ON SOME SPIN. WITH LOW LCLS EXPECTED IN THE VERY TROPICAL
AIRMASS...HAVE TO STAY AWARE OF THE POTENTIAL FOR AN ISOLATED
TORNADO. AS IT STANDS RIGHT NOW...THE SEVERE THREAT WILL BE VERY
DEPENDENT ON GETTING THE SUN TO COME OUT AND FIRST COOK UP THE
CAPES.
WITH AN ANOMALOUSLY STRONG LOW LEVEL JET AND PURE TROPICAL
AIR...ANOTHER THREAT WILL BE LOCALLY HEAVY RAIN IN SOME OF THE
THUNDERSTORMS. IT HAS BEEN DRY SO NO HEADLINES ARE PLANNED...BUT
WILL OPT FOR SOME ENHANCED WORDING IN THE FORECAST AND HWO
PRODUCT.
HIGHS WILL NOT BE TERRIBLY HIGH...IN THE MID 70S TO MID 80S FROM
NW TO SE...BUT DEWPOINTS WELL UP IN THE 60S TO LOWER 70S WILL
BRING ONE OF THE MORE UNCOMFORTABLY HUMID DAYS WE`VE SEEN THIS
SUMMER.
IT`S HARD TO PIN DOWN WHAT WILL OCCUR OVERNIGHT WITH REGARD TO
CONVECTION. ECMWF/NAM/GFS ALL PAINT DIFFERENT SCENARIOS. THE
NAM/SREF REPRESENT THE WETTEST SOLUTIONS WITH SOME SORT OF MESO
LOW TRACKING ACROSS SOUTHERN PA. THE GFS/GEFS ARGUE FOR SMALLER
CHANCES OF RAIN WITH MOST OF THE AREA SEEING WEAK LOW LEVEL
RIDGING DEVELOP IN THE WAKE OF TODAY`S EVENTS. THE ECMWF IS THE
DRIEST OF ALL. RIGHT NOW WE HAVE LIKELY POPS OVER THE SOUTH AND
CHANCE OVER THE NORTH. UNLESS I SEE SOMETHING COMPELLING...WILL
PROBABLY NOT CHANGE IT MUCH GIVEN THE EXPECTATIONS OF LITTLE OR
NO REAL FOCUSING MECHANISM.
ANOTHER WARM MUGGY NIGHT IS IN STORE AS THE AIRMASS WILL REMAIN
VIRTUALLY UNCHANGED.
&&
.SHORT TERM /MONDAY/...
AT THIS TIME I AM HOLDING OUT HOPE OF A DRIER LABOR DAY...BUT
CANNOT DROP THE MENTION OF RAIN ALTOGETHER. SREF/GEFS BOTH SHOW
THE ANOMALOUS PWAT PLUME SLIDING EAST WITH DRYING TAKING PLACE
LOCALLY. SHORT RANGE OPERATIONAL GUIDANCE HINTS AT WEAK SHORTWAVE
RIDGING AND RISING UPPER HEIGHTS...SO I TRENDED POPS DOWN DURING
THE DAY WITH THE THINKING BEING THAT MOST AREAS WILL HAVE A DRY
AFTERNOON AND EVENING FOR THE LAST OF THE TRADITIONAL SUMMER`S
COOKOUTS.
OVERALL IT WILL NOT FEEL SIGNIFICANTLY DRIER HOWEVER AS
TEMPERATURES WILL ONCE AGAIN RISE INTO THE 70S AND 80S WITH
DEWPOINTS REMAINING TROPICAL IN THE 60S AND LOWER 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
STILL PRETTY GOOD AGREEMENT IN A COLD FRONT SWINGING THROUGH THE
STATE LATE TUESDAY. THIS SHOULD PROVIDE THE BEST CHANCE OF RAIN
IN THE EXTENDED BEFORE HIGH PRESSURE BUILDS IN FOR
MIDWEEK...BRINGING A FEW DAYS OF MILD AND DRY WEATHER. THE NEXT
CHANCE FOR RAIN LOOKS LIKE IT WILL NOT BE UNTIL LATER IN THE WEEK
WHEN A MORE HUMID FLOW WILL DEVELOP AROUND THE HIGH MOVING OFF THE
COAST. AT THIS POINT A COLD FRONT LOOKS LIKELY FOR SATURDAY
FOLLOWED BY A COOLER AIRMASS FOR NEXT WEEKEND.
THIS UPCOMING WEEK WILL BE ONE OF THE RARE EXTENDED PERIODS OF
WARMER THAN NORMAL TEMPERATURES WE HAVE SEEN THIS SUMMER. HIGH
TEMPERATURES WILL CLIMB TO ALMOST 90 ACROSS THE SOUTH AND EAST ON
TUESDAY AHEAD OF THE FRONTAL PASSAGE. THEN AN UPPER RIDGE WILL
BUILD OVER THE EASTERN US FOR THE SECOND HALF OF THE
WEEK...KEEPING HIGH TEMPERATURES AT OR SLIGHTLY ABOVE SEASONAL
NORMALS FOR EARLY SEPTEMBER.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MAIN AREAS THAT STILL HAVE CIGS IN THE 1500 RANGE IS
IPT...MDT...AND LNS. MOST OF THE LOWER CIGS OUT OF THE
UNV...AOO...AND JST. SHOWERS IN THE BFD AREA AT 12Z.
RATHER FAST MOVING BOW ECHO WILL MOVE JUST NORTH OF
UNV.
WILL ADJUST THE 12Z TAFS.
ANYWAY...THE MAIN ISSUE NOW IS THE LARGE AREA OF SHOWERS
AND THUNDERSTORMS JUST MOVING INTO OUR AREA FROM PIT.
BEEN UPDATING FCST AS NEEDED.
OUTLOOK...
MON...AM FOG POSS...ESP W MTNS. ISOLD PM TSRA IMPACTS
POSS.
TUE...SCT PM TSRA IMPACTS POSS.
WED...PATCHY AM FOG POSS.
THU...PATCHY AM FOG POSS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
556 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A WARM AND HUMID SOUTHWEST FLOW WILL KEEP THE CHANCES FOR RAIN IN
THE FORECAST THROUGH THE LABOR DAY HOLIDAY. A COLD FRONT WILL
BRING A BREAK IN THE HUMIDITY FOR MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE RADAR BECOMING MORE ACTIVE WITH SCATTERED SHOWERS AND
THUNDERSTORMS MOVING THROUGH WRN PA...MAKING SLOW PROGRESS TOWARD
MY FCST AREA.
THE HRRR SHOWS THE RAIN CURRENTLY FROM KENTUCKY INTO SOUTHERN OHIO
CONTINUING TO MARCH NORTHEAST THROUGH MORNING WITH MOST OF MY
WESTERN ZONES GETTING WET BY ABOUT 6-7AM...AND MUCH OF THE REST OF
MY FCST AREA COVERED WITH SHOWERS AND THUNDERSTORMS BY MID DAY.
THIS AFTERNOON WE COULD ALSO SEE A SEVERE THREAT DEVELOP FOR MY
SERN ZONES. MODELS ARE COOKING UP A FAIR AMOUNT OF CAPE OVER
EASTERN AREAS HINTING THAT THE THE CLOUDS WILL BE LESS EXTENSIVE
ALLOWING FOR MORE IN THE WAY OF SOLAR HEATING. FORECAST MID LEVEL
LAPSE RATES ARE WEAK BUT SHEAR WILL INCREASE WHICH COULD AID IN
ORGANIZING STORM DEVELOPMENT.
MODELS ALSO PROG A WEAK LOW LEVEL CONVERGENCE ZONE...PERHAPS THE
REMNANTS OF THE OLD WARM FRONT WHERE ENHANCED LOW LEVEL
SHEAR...EHI`S PROGGED 1-3(M^2/S^2) COULD HELP A STORM OR TWO TAKE
ON SOME SPIN. WITH LOW LCLS EXPECTED IN THE VERY TROPICAL
AIRMASS...HAVE TO STAY AWARE OF THE POTENTIAL FOR AN ISOLATED
TORNADO. AS IT STANDS RIGHT NOW...THE SEVERE THREAT WILL BE VERY
DEPENDENT ON GETTING THE SUN TO COME OUT AND FIRST COOK UP THE
CAPES.
WITH AN ANOMALOUSLY STRONG LOW LEVEL JET AND PURE TROPICAL
AIR...ANOTHER THREAT WILL BE LOCALLY HEAVY RAIN IN SOME OF THE
THUNDERSTORMS. IT HAS BEEN DRY SO NO HEADLINES ARE PLANNED...BUT
WILL OPT FOR SOME ENHANCED WORDING IN THE FORECAST AND HWO
PRODUCT.
HIGHS WILL NOT BE TERRIBLY HIGH...IN THE MID 70S TO MID 80S FROM
NW TO SE...BUT DEWPOINTS WELL UP IN THE 60S TO LOWER 70S WILL
BRING ONE OF THE MORE UNCOMFORTABLY HUMID DAYS WE`VE SEEN THIS
SUMMER.
IT`S HARD TO PIN DOWN WHAT WILL OCCUR OVERNIGHT WITH REGARD TO
CONVECTION. ECMWF/NAM/GFS ALL PAINT DIFFERENT SCENARIOS. THE
NAM/SREF REPRESENT THE WETTEST SOLUTIONS WITH SOME SORT OF MESO
LOW TRACKING ACROSS SOUTHERN PA. THE GFS/GEFS ARGUE FOR SMALLER
CHANCES OF RAIN WITH MOST OF THE AREA SEEING WEAK LOW LEVEL
RIDGING DEVELOP IN THE WAKE OF TODAY`S EVENTS. THE ECMWF IS THE
DRIEST OF ALL. RIGHT NOW WE HAVE LIKELY POPS OVER THE SOUTH AND
CHANCE OVER THE NORTH. UNLESS I SEE SOMETHING COMPELLING...WILL
PROBABLY NOT CHANGE IT MUCH GIVEN THE EXPECTATIONS OF LITTLE OR
NO REAL FOCUSING MECHANISM.
ANOTHER WARM MUGGY NIGHT IS IN STORE AS THE AIRMASS WILL REMAIN
VIRTUALLY UNCHANGED.
&&
.SHORT TERM /MONDAY/...
AT THIS TIME I AM HOLDING OUT HOPE OF A DRIER LABOR DAY...BUT
CANNOT DROP THE MENTION OF RAIN ALTOGETHER. SREF/GEFS BOTH SHOW
THE ANOMALOUS PWAT PLUME SLIDING EAST WITH DRYING TAKING PLACE
LOCALLY. SHORT RANGE OPERATIONAL GUIDANCE HINTS AT WEAK SHORTWAVE
RIDGING AND RISING UPPER HEIGHTS...SO I TRENDED POPS DOWN DURING
THE DAY WITH THE THINKING BEING THAT MOST AREAS WILL HAVE A DRY
AFTERNOON AND EVENING FOR THE LAST OF THE TRADITIONAL SUMMER`S
COOKOUTS.
OVERALL IT WILL NOT FEEL SIGNIFICANTLY DRIER HOWEVER AS
TEMPERATURES WILL ONCE AGAIN RISE INTO THE 70S AND 80S WITH
DEWPOINTS REMAINING TROPICAL IN THE 60S AND LOWER 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
STILL PRETTY GOOD AGREEMENT IN A COLD FRONT SWINGING THROUGH THE
STATE LATE TUESDAY. THIS SHOULD PROVIDE THE BEST CHANCE OF RAIN
IN THE EXTENDED BEFORE HIGH PRESSURE BUILDS IN FOR
MIDWEEK...BRINGING A FEW DAYS OF MILD AND DRY WEATHER. THE NEXT
CHANCE FOR RAIN LOOKS LIKE IT WILL NOT BE UNTIL LATER IN THE WEEK
WHEN A MORE HUMID FLOW WILL DEVELOP AROUND THE HIGH MOVING OFF THE
COAST. AT THIS POINT A COLD FRONT LOOKS LIKELY FOR SATURDAY
FOLLOWED BY A COOLER AIRMASS FOR NEXT WEEKEND.
THIS UPCOMING WEEK WILL BE ONE OF THE RARE EXTENDED PERIODS OF
WARMER THAN NORMAL TEMPERATURES WE HAVE SEEN THIS SUMMER. HIGH
TEMPERATURES WILL CLIMB TO ALMOST 90 ACROSS THE SOUTH AND EAST ON
TUESDAY AHEAD OF THE FRONTAL PASSAGE. THEN AN UPPER RIDGE WILL
BUILD OVER THE EASTERN US FOR THE SECOND HALF OF THE
WEEK...KEEPING HIGH TEMPERATURES AT OR SLIGHTLY ABOVE SEASONAL
NORMALS FOR EARLY SEPTEMBER.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
CIGS AT MANY SPOTS SUCH AS UNV AND AOO GOING BETWEEN SCT015
AMD BKN015 FOR EXAMPLE...AS BEEN THE CASE SINCE YESTERDAY.
ANYWAY...THE MAIN ISSUE NOW IS THE LARGE AREA OF SHOWERS
AND THUNDERSTORMS JUST STARTING TO MOVE INTO OUR AREA FROM
PIT.
BEEN UPDATING FCST AS NEEDED.
OUTLOOK...
MON...AM FOG POSS...ESP W MTNS. ISOLD PM TSRA IMPACTS
POSS.
TUE...SCT PM TSRA IMPACTS POSS.
WED...PATCHY AM FOG POSS.
THU...PATCHY AM FOG POSS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
444 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A WARM AND HUMID SOUTHWEST FLOW WILL KEEP THE CHANCES FOR RAIN IN
THE FORECAST THROUGH THE LABOR DAY HOLIDAY. A COLD FRONT WILL
BRING A BREAK IN THE HUMIDITY FOR MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE RADAR BECOMING MORE ACTIVE WITH SCATTERED SHOWERS AND
THUNDERSTORMS MOVING THROUGH WRN PA...MAKING SLOW PROGRESS TOWARD
MY FCST AREA.
THE HRRR SHOWS THE RAIN CURRENTLY FROM KENTUCKY INTO SOUTHERN OHIO
CONTINUING TO MARCH NORTHEAST THROUGH MORNING WITH MOST OF MY
WESTERN ZONES GETTING WET BY ABOUT 6-7AM...AND MUCH OF THE REST OF
MY FCST AREA COVERED WITH SHOWERS AND THUNDERSTORMS BY MID DAY.
THIS AFTERNOON WE COULD ALSO SEE A SEVERE THREAT DEVELOP FOR MY
SERN ZONES. MODELS ARE COOKING UP A FAIR AMOUNT OF CAPE OVER
EASTERN AREAS HINTING THAT THE THE CLOUDS WILL BE LESS EXTENSIVE
ALLOWING FOR MORE IN THE WAY OF SOLAR HEATING. FORECAST MID LEVEL
LAPSE RATES ARE WEAK BUT SHEAR WILL INCREASE WHICH COULD AID IN
ORGANIZING STORM DEVELOPMENT.
MODELS ALSO PROG A WEAK LOW LEVEL CONVERGENCE ZONE...PERHAPS THE
REMNANTS OF THE OLD WARM FRONT WHERE ENHANCED LOW LEVEL
SHEAR...EHI`S PROGGED 1-3(M^2/S^2) COULD HELP A STORM OR TWO TAKE
ON SOME SPIN. WITH LOW LCLS EXPECTED IN THE VERY TROPICAL
AIRMASS...HAVE TO STAY AWARE OF THE POTENTIAL FOR AN ISOLATED
TORNADO. AS IT STANDS RIGHT NOW...THE SEVERE THREAT WILL BE VERY
DEPENDENT ON GETTING THE SUN TO COME OUT AND FIRST COOK UP THE
CAPES.
WITH AN ANOMALOUSLY STRONG LOW LEVEL JET AND PURE TROPICAL
AIR...ANOTHER THREAT WILL BE LOCALLY HEAVY RAIN IN SOME OF THE
THUNDERSTORMS. IT HAS BEEN DRY SO NO HEADLINES ARE PLANNED...BUT
WILL OPT FOR SOME ENHANCED WORDING IN THE FORECAST AND HWO
PRODUCT.
HIGHS WILL NOT BE TERRIBLY HIGH...IN THE MID 70S TO MID 80S FROM
NW TO SE...BUT DEWPOINTS WELL UP IN THE 60S TO LOWER 70S WILL
BRING ONE OF THE MORE UNCOMFORTABLY HUMID DAYS WE`VE SEEN THIS
SUMMER.
IT`S HARD TO PIN DOWN WHAT WILL OCCUR OVERNIGHT WITH REGARD TO
CONVECTION. ECMWF/NAM/GFS ALL PAINT DIFFERENT SCENARIOS. THE
NAM/SREF REPRESENT THE WETTEST SOLUTIONS WITH SOME SORT OF MESO
LOW TRACKING ACROSS SOUTHERN PA. THE GFS/GEFS ARGUE FOR SMALLER
CHANCES OF RAIN WITH MOST OF THE AREA SEEING WEAK LOW LEVEL
RIDGING DEVELOP IN THE WAKE OF TODAY`S EVENTS. THE ECMWF IS THE
DRIEST OF ALL. RIGHT NOW WE HAVE LIKELY POPS OVER THE SOUTH AND
CHANCE OVER THE NORTH. UNLESS I SEE SOMETHING COMPELLING...WILL
PROBABLY NOT CHANGE IT MUCH GIVEN THE EXPECTATIONS OF LITTLE OR NO
REAL FOCUSING MECHANISM.
ANOTHER WARM MUGGY NIGHT IS IN STORE AS THE AIRMASS WILL REMAIN
VIRTUALLY UNCHANGED.
&&
.SHORT TERM /MONDAY/...
AT THIS TIME I AM HOLDING OUT HOPE OF A DRIER LABOR DAY...BUT
CANNOT DROP THE MENTION OF RAIN ALTOGETHER. SREF/GEFS BOTH SHOW
THE ANOMALOUS PWAT PLUME SLIDING EAST WITH DRYING TAKING PLACE
LOCALLY. SHORT RANGE OPERATIONAL GUIDANCE HINTS AT WEAK SHORTWAVE
RIDGING AND RISING UPPER HEIGHTS...SO I TRENDED POPS DOWN DURING
THE DAY WITH THE THINKING BEING THAT MOST AREAS WILL HAVE A DRY
AFTERNOON AND EVENING FOR THE LAST OF THE TRADITIONAL SUMMER`S
COOKOUTS.
OVERALL IT WILL NOT FEEL SIGNIFICANTLY DRIER HOWEVER AS
TEMPERATURES WILL ONCE AGAIN RISE INTO THE 70S AND 80S WITH
DEWPOINTS REMAINING TROPICAL IN THE 60S AND LOWER 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
STILL PRETTY GOOD AGREEMENT IN A COLD FRONT SWINGING THROUGH THE
STATE LATE TUESDAY. THIS SHOULD PROVIDE THE BEST CHANCE OF RAIN IN
THE EXTENDED BEFORE HIGH PRESSURE BUILDS IN FOR
MIDWEEK...BRINGING A FEW DAYS OF MILD AND DRY WEATHER. THE NEXT
CHANCE FOR RAIN LOOKS LIKE IT WILL NOT BE UNTIL LATER IN THE WEEK
WHEN A MORE HUMID FLOW WILL DEVELOP AROUND THE HIGH MOVING OFF THE
COAST. AT THIS POINT A COLD FRONT LOOKS LIKELY FOR SATURDAY
FOLLOWED BY A COOLER AIRMASS FOR NEXT WEEKEND.
THIS UPCOMING WEEK WILL BE ONE OF THE RARE EXTENDED PERIODS OF
WARMER THAN NORMAL TEMPERATURES WE HAVE SEEN THIS SUMMER. HIGH
TEMPERATURES WILL CLIMB TO ALMOST 90 ACROSS THE SOUTH AND EAST ON
TUESDAY AHEAD OF THE FRONTAL PASSAGE. THEN AN UPPER RIDGE WILL
BUILD OVER THE EASTERN US FOR THE SECOND HALF OF THE
WEEK...KEEPING HIGH TEMPERATURES AT OR SLIGHTLY ABOVE SEASONAL
NORMALS FOR EARLY SEPTEMBER.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THERE WERE A FEW STORMS ACROSS THE NW AT MIDNIGHT. MOST OF THESE
NE OF OUR AREA...UP IN WESTERN NY.
MAIN ISSUE OVERNIGHT WILL BE A WIDE RANGE OF CONDITIONS. LOW
CIGS WILL BE IN SOME SPOTS.
06Z TAFS SENT.
EARLIER DISCUSSION BELOW.
LATE EVENING SATL IMAGERY SHOWS STRATUS COVERING THE EASTERN HALF
OF THE STATE...THE RESULT OF MOIST SERLY FLOW OFF THE ATLANTIC
OCEAN. FURTHER WEST...WIDESPREAD VFR NOTED ACROSS THE WESTERN HALF
OF THE STATE.
ALL MDL DATA POINTS TOWARD DETERIORATING FLYING CONDS
OVERNIGHT. PLUME OF HIGH MOISTURE IS IN PLACE OVR CENTRAL PA AND
AS LOW LVLS COOL...EXPECT LOWERING STRATUS OVR MOST OF CENTRAL PA.
THE WORST CONDS IN THE FORM OF IFR CIGS ARE LIKELY TO BE AT KBFD
LATE TONIGHT...WHERE SW FLOW ASCENDS THE HIGHER TERRAIN OF NW PA.
MOS GUIDANCE INDICATING A DIP TO IFR CIGS ACROSS MUCH OF CENTRAL
PA EARLY SUN AM. HOWEVER...BASED ON LATEST SREF OUTPUT AND
EXPECTED SOUTHERLY FLOW RATHER THAN SERLY...BELIEVE MVFR CIGS ARE
MORE LIKELY FROM KAOO AND KUNV EASTWARD. THE BEST FLYING CONDS ARE
LIKELY TO BE AT KJST...WHERE SOUTH WIND DOWNSLOPING THE HIGHER
TERRAIN OF THE CENTRAL APPALACHIANS MAY KEEP CONDS VFR THERE
OVERNIGHT.
A TROUGH OF LOW PRESSURE APPROACHING FROM THE GRT LKS WILL SPREAD
A BAND OF SHRA INTO NW PA SUNDAY MORNING. SCT SHRA/TSRA WILL
DEVELOP AHEAD OF THIS FEATURE OVR THE REST OF CENTRAL PA BY SUN
AFTN. LOCALIZED VSBY REDUCTIONS ARE POSSIBLE IN ANY OF THESE
SHOWERS. HOWEVER...THE BIGGEST AVIATION CONCERN SUNDAY WILL BE THE
POSSIBLE LOW CIGS IN THE MORNING...ESP KBFD. PREDOMINANTLY VFR
CONDS ARE LIKELY BY SUNDAY AFTN.
OUTLOOK...
MON...AM FOG POSS...ESP W MTNS. ISOLD PM TSRA IMPACTS POSS.
TUE...SCT PM TSRA IMPACTS POSS.
WED...PATCHY AM FOG POSS.
THU...PATCHY AM FOG POSS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...FITZGERALD/MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
150 AM EDT SUN AUG 31 2014
.SYNOPSIS...
A BERMUDA HIGH WILL DEVELOP AND LINGER INTO EARLY NEXT WEEK...
RESULTING IN TYPICAL SUMMERTIME HEAT AND SCATTERED AFTERNOON
THUNDERSTORMS EACH DAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 145 AM EDT SUNDAY...BAND OF CONVECTION CONTINUES TO SLOWLY
PUSH EAST ACROSS NORTHEAST GA AND SOUTHWEST NC THIS MORNING.
LIGHT/MODERATE PRECIPIATION RATES HAVE BEEN OBSERVED WITH A FEW
LOCATIONS RECEIVING NEARLY AN INCH PER HOUR. AS THIS CONVECTION
CONTINUES TO MOVE EAST INTO THE WESTERN UPSTATE OF SC...EXPECTING A
WEAKENING TREND TO PREVAIL WITH DECREASING RAIN RATES LIKELY. THAT
SAID...DECIDED TO INCREASE POPS SUBSTANTIALLY FOR THESE AFFECTED
ZONES OVER THE NEXT FEW HOURS WITH POPS TRENDING DOWN NEAR
DAYBREAK. ALSO MADE QPF ADJUSTMENTS TO ACCOUNT FOR ABOVE MENTIONED
RAIN RATES WHICH DID NOT REVEAL ANY FLOODING CONCERNS AS FORWARD
PROPAGATION REMAINS SUFFICIENT. OTHERWISE...TWEAKED TEMPERATURES
AND DEWPOINTS TO REFLECT LATEST OBSERVATIONAL TRENDS WITH NO OTHER
CHANGES MADE.
PREVIOUS DISCUSSIONS...
EVENING UPDATE...MADE A NOTABLE CHANGE TO THE POP/WX/QPF GRIDS
OVERNIGHT. THE LAST FEW RUNS OF THE HRRR HAVE BEEN CONSISTENT AND
THE LATEST OP MODELS HAVE CAUGHT ONTO THE IDEA OF A LINE OF
-SHRA/TSRA ORGANIZING ACROSS THE SW/RN ZONES ARND 06Z THEN PUSHING
NE THRU 12Z BEFORE DISSIPATING. WONT ANTICIPATE STRONG WX WITH THIS
LINE AS IT MOVES UNDERNEATH STRONG RIDGING ALOFT AND INSTABILITY
WILL BE WEAK THROUGH A DEEP LAYER. OTHERWISE...A FG THREAT ACROSS
THE MTNS AND NC FTHILLS WILL BE CURTAILED WITH CONTINUED BKN/OVC
CLOUD COVER...YET PATCHY VSBYS IN THE ONE MILE OR LESS RANGE COULD
DEVELOP ACROSS THE NC MTN VALLEYS BEFORE DAYBREAK AS CLOUDS THIN
FROM THE SW AFT 09Z. MIN TEMPS WERE BUMPED UP A DEGREE OR TWO MOST
LOCALE BASED ON LATEST TRENDS AND ANTICIPATED SLOW COOLING
RATES.
AS OF 215 PM...LATEST CAM`S SHOWING A LITTLE MORE CONVECTIVE
RESPONSE THIS AFTERNOON SO HAVE NUDGED THE POPS HIGHER OVER THE
WESTERN UPSTATE AND THE MOUNTAINS. IT STILL LOOKS LIKE CONVECTIVE
COVERAGE WILL INCREASE AS THE AFTERNOON PROGRESSES OVER NE GA AND
THE SW MOUNTAINS...WITH COVERAGE THEN SPREADING NE INTO THE CENTRAL
MOUNTAINS/NORTHERN MOUNTAINS DURING THE EVENING HOURS AS A WEAK
SHORT WAVE MOVES THROUGH TN. CAN`T RULE OUT SOME SHOWERS/STORMS
AFFECTING THE ADJACENT FOOTHILLS/PIEDMONT DURING THE EVENING SO HAVE
BUMPED POPS UPWARD THERE PER LATEST CAMS. HAVE DISCOUNTED THE
SPURIOUS DEEP CONVECTION AND HEAVY QPF THAT THE NAM DEVELOPS IN THE
NC PIEDMONT OVERNIGHT. DO NOT SEE THE TRIGGERING MECHANISM FOR SUCH
A RESPONSE AND THERE IS NO SUPPORT FROM ANY OTHER MODEL.
IN REGARD TO THE BIG PICTURE...THE UPPER HIGH WILL BE GRADUALLY
SUPPRESSED TO THE SE AS A SERIES OF SHORT WAVES MOVE THROUGH THE TN
VALLEY INTO THE MID-ATLANTIC STATES. THE FIRST OF THESE SHORT WAVES
WILL MOVE BY THIS EVENING AND THEN ANOTHER ON SUNDAY. AS THE FIRST
WAVE MOVES BY TO THE WEST TONIGHT...SCT SHOWERS AND STORMS WILL
OCCUR MAINLY OVER THE MOUNTAINS...POSSIBLY CONTINUING INTO THE EARLY
MORNING HOURS OF SUNDAY. WITH MOIST PROFILES AND WEAK WIND FIELDS...
SEVERE STORMS ARE NOT EXPECTED. HOWEVER...SOME LOCALLY HEAVY IS
POSSIBLE.
ON SUNDAY...SCT SHOWERS AND STORMS ARE EXPECTED TO DEVELOP AGAIN AS
ANOTHER SHORT WAVE MOVES BY TO THE WEST COINCIDING WITH MAX HEATING.
THE MODELS HAVE BEEN TRENDING AWAY FROM SHOWING MUCH QPF RESPONSE
OUTSIDE THE MOUNTAINS ON SUNDAY. HENCE...HAVE DIALED BACK POPS TO
THE SLIGHT CHANCE/CHANCE RANGE OVER THE PIEDMONT. THE BEST COVERAGE
SHOULD BE ALONG THE SPINE OF THE MOUNTAINS WHERE NUMEROUS STORMS MAY
OCCUR.
USED OUR CONSALL BLEND TO POPULATE MOST FIELDS. TEMPS WILL CONTINUE
ABOVE CLIMO. MAX TEMPS ON SUNDAY WILL BE CLOSE TO TODAY`S
NUMBERS...THOUGH PERHAPS A COUPLE DEGREES LESS WARM IN THE MOUNTAINS
DUE TO MORE CONVECTIVE COVERAGE.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 200 PM SATURDAY...FAIRLY STANDARD LATE SUMMER WEATHER IS
EXPECTED THROUGH THE SHORT TERM...AS SUBTROPICAL/BERMUDA HIGH
PRESSURE REMAINS AS THE DOMINANT SYNOPTIC SCALE FEATURE ACROSS THE
SOUTHEAST. THIS SHOULD GENERALLY SUPPORT WARM AND HUMID CONDITIONS
THROUGH THE PERIOD...WITH CHANCES FOR DIURNAL CONVECTION GENERALLY
EXPECTED TO BE NEAR TO SLIGHTLY ABOVE CLIMO (30 PERCENT MTNS/20
PERCENT ACROSS THE LOWER TERRAIN) MON AND TUE AFTERNOONS. CONVECTIVE
CHANCES MAY INCREASE SLIGHTLY ACROSS OUR WESTERN AREAS BY TUE
EVENING...AS DEEP LAYER MOISTURE INCREASES AHEAD OF A WEAK FRONTAL
ZONE. TEMPERATURES ARE EXPECTED TO REMAIN ABOUT A CATEGORY ABOVE
NORMAL THROUGH THE PERIOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM EDT SATURDAY...THE LATEST GLOBAL MODELS INDICATE THAT
H5 HEIGHTS WILL CONTINUE TO RISE OVER THE FORECAST AREA TUE NIGHT
INTO FRI AS A BROAD UPPER RIDGING AMPLIFIES ACROSS THE SOUTHEAST AND
GULF STATES. BY SAT...WEAK UPPER NWLY FLOW WILL SET UP AS THE CENTER
OF UPPER ANTICYCLONE RETROGRADES TOWARD THE WESTERN CONUS. AT THE
SURFACE...HIGH PRESSURE WILL WEAKEN AND SLIDE SOUTH OF THE AREA TUE
NIGHT AS A WEAK COLD FRONT APPROACHES FROM THE NW. THE FRONT WILL
PUSH THRU THE AREA ON WED AND BECOMES STATIONARY JUST TO OUR SOUTH
BY THU. A BERMUDA HIGH WILL THEN BUILD BACK IN FROM THE SE BY FRI
AND REMAIN IN PLACE THRU DAY 7. AS FOR OUR SENSIBLE WEATHER...HAVE
MENTIONED 30/40 POPS WED/THU DUE TO INCREASING MOISTURE AND BUOYANCY
ALONG AND AHEAD OF THE FRONT. FRI/SAT...DIURNAL BUOYANCY AND
MOISTURE UNDER THE INFLUENCE OF BERMUDA HIGH WILL BE SUPPORTIVE OF
SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS ON EACH
DAY...MAINTAINING POPS IN THE 30/40 RANGE. TEMPERATURES WILL STAY
AROUND 2-5 DEGREES ABOVE NORMAL WED/THU BEFORE COOLING TO NEAR
NORMAL BY FRI.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AT KCLT...VFR CONDITIONS WILL PREVAIL INITIALLY AHEAD OF POSSIBLE
VISB REDUCTIONS NEAR DAYBREAK. INITIALIZED TAF VFR WITH 07KT
SOUTHERLY WINDS UNDER SCT LOW VFR STRATOCU. INTRODUCED 2HR TEMPO AT
11Z TO ACCOUNT FOR DECOUPLING PBL AND POTENTIAL MVFR LEVEL FOG
RESTRICTIONS. BY 13Z CONDITIONS WILL IMPROVE UNDER BKN/OVC LOW
LEVEL STRATUS LASTING THROUGH MUCH OF THE MORNING BEFORE LOW LEVEL
MOISTURE MIXES OUT. BY MIDDAY...SKIES WILL FEATURE SCT MID/HIGH
LEVEL CLOUDS WITH INCREASING SOUTHERLY WINDS FOR THE REMAINDER OF
THE PERIOD. AS FOR WX...CURRENT RADAR TRENDS AND LATEST CAM
GUIDANCE INDICATE BAND OF CONVECTION ACROSS NORTHEAST GA WILL NOT
SURVIVE THE TRIP EAST INTO THE NC PIEDMONT...THEREFORE NO WX MENTION
FOR THIS FEATURE. HOWEVER...AS THE PROFILE HEATS DURING THE
AFTERNOON HOURS ON SUNDAY CANNOT RULE OUT SHRA/TSRA LATE IN THE DAY
THEREFORE KEPT PREVIOUS PROB30 FOR SUCH.
ELSEWHERE...A MIXTURE OF VFR/MVFR AND POSSIBLE IFR CONDITIONS WILL
BE POSSIBLE THROUGH THE EVENING AT ALL SITES. ABOVE MENTIONED BAND
OF CONVECTION WILL SPREAD EAST AFFECTING THE SC SITES ALONG WITH
KAVL THROUGH THE OVERNIGHT. THEREFORE EACH TAF LOCATION FEATURES
PREVAILING VCTS LEADING UP TO ARRIVAL WITH A TEMPO FOR TSRA AND IFR
CIGS/VISB DURING PASSAGE. CONDITIONS WILL SLOWLY IMPROVE AFTER
DAYBREAK AT ALL SITES AS ABOVE MENTIONED SHRA/TSRA ERODES ALONG WITH
INCREASING CLOUD BASES. VFR WILL PREVAIL LATE IN THE PERIOD WITH
THE EXCEPTION OF PROB30 MENTION AT KAVL AND KHKY TO ACCOUNT FOR
AFTERNOON CONVECTION. WINDS THROUGH THE PERIOD WILL REMAIN
SOUTHERLY WITH FLOW INCREASING INTO SUNDAY AFTERNOON.
OUTLOOK...GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH EARLY NEXT
WEEK WITH THE EXCEPTION FOR RESTRICTIONS IN THE EARLY MORNING DUE TO
LOW CLOUDS AND FOG...PRIMARILY IN THE MOUNTAIN VALLEYS. DIURNAL
CONVECTION IS EXPECTED EACH AFTERNOON WITH THE MOST COVERAGE OVER
THE MOUNTAINS.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP MED 72% MED 66% HIGH 100% HIGH 100%
KAVL HIGH 84% HIGH 86% HIGH 100% HIGH 100%
KHKY MED 79% HIGH 92% HIGH 100% HIGH 100%
KGMU HIGH 81% LOW 58% HIGH 100% HIGH 100%
KAND HIGH 81% MED 68% 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/LG/SBK
SHORT TERM...JDL
LONG TERM...JOH
AVIATION...CDG
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
331 PM CDT SUN AUG 31 2014
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
POTENT SHORTWAVE EVIDENT ON WATER VAPOR OVER WYOMING. AHEAD OF
THIS WAVE...OMEGA AND UPPER JET MAX HELPING TO MAINTAIN BAND OF
RAINFALL THAT HAS TREKKED FROM SOUTH CENTRAL SD TO NORTHEAST SD
OVER THE PAST SEVERAL HOURS. HAVE BEEN ADJUSTING POPS FOR THIS
BAND OF RAIN AS IT APPEARS IT WILL SURVIVE MOST IF NOT ALL THE WAY
ACROSS THE CWA. HRRR PICKING UP ON THIS QUITE NICELY.
OVERNIGHT...EXPECTING SCATTERED SHOWERS AND STORMS TO MOVE EAST
ACROSS THE STATE BUT WITH MINIMAL SEVERE THREAT DUE TO LACK OF
INSTABILITY. ONLY QUESTION IS THE DEGREE OF AREAL COVERAGE OF
PRECIP. SOME MODELS GREATER THAN OTHERS...WITH THE HRRR
PARTICULARLY DRY AND SORT OF THE OUTLIER. MOST OTHER MODELS HAVE
ACTIVITY MOVING ACROSS AT LEAST THE SOUTHERN HALF OF SD TONIGHT.
HAVE ADJUSTED POPS ACCORDINGLY AND LINGERED THEM A BIT LONGER
THROUGH THE NIGHT AS NSSL WRF STILL SHOWS CONVECTIVE CLUSTERS OVER
SOUTHEAST SD AT 09Z TONIGHT.
A WEAKER WAVE MOVES ACROSS THE AREA MONDAY...BUT SHOULD STILL
PROVIDE FOR A FEW SCATTERED SHOWERS OR STORMS. AREAL COVERAGE DOES
NOT APPEAR IT WILL QUITE MATCH UP TO WHATS MOVING INTO WESTERN SD
RIGHT NOW...BUT WORTHY OF 20/30 POPS NONETHELESS. AGAIN A LACK OF
INSTABILITY TOMORROW SO SEVERE THREAT IS VERY LOW.
TUESDAY STILL LOOKS DRY WITH NO NOTABLE SYSTEMS IN THE AREA. 500
MB HEIGHTS RISE SLOWLY THROUGH THE DAY WITH WARM AIR ADVECTION
DEVELOPING. HIGHS WILL BUMP UP INTO THE UPPER 70S TO LOW 80S FOR
MOST AREAS.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
THE EARLY PART OF THE PERIOD STARTS OFF SOMEWHAT ACTIVE AS FAIRLY
STRONG SYSTEM MOVES ACROSS THE NORTHERN PLAINS. LATEST MODELS ARE
IN FAIR AGREEMENT ON AVAILABLE MOISTURE/INSTABILITY BUT DO SUGGEST
CAPPING MIGHT FORCE MOST ACTIVITY TO REMAIN NORTH OF THE CWA
WEDNESDAY NIGHT INTO THURSDAY AS COLD FRONT MOVES EAST. THUS POPS
NO HIGHER THAN CHC NEEDED AT THIS POINT. BEHIND THE FRONT IT
LOOKS FAIRLY DRY FROM THURSDAY THROUGH SUNDAY AS HIGH PRESSURE
PROVES DOMINANT. TEMPERATURES WILL START OFF ABOVE NORMAL AT THE
BEGINNING OF THE PERIOD THEN TREND TOWARD NORMAL OR EVEN BELOW BY
THE END OF THE WEEK.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
WHATEVER LEFTOVER MVFR CIGS ARE HANGING AROUND SHOULD DISSIPATE
THIS AFTERNOON. AN AREA OF RAIN/SHOWERS ASSOCIATED WITH AN MCV IS
LIKELY TO AFFECT KPIR/KATY/KABR THIS AFTERNOON INTO THE EARLY
EVENING HOURS. OVERALL VFR CONDITIONS ARE EXPECTED LATER THIS
AFTERNOON THROUGH TONIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...TMT
LONG TERM...TDK
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1244 PM CDT SUN AUG 31 2014
.UPDATE...
AVIATION DISCUSSION UPDATED BELOW.
SOMEWHAT DIFFICULT FORECAST SHAPING UP FOR TODAY WITH A FEW
UNCERTAINTIES. FAIRLY POTENT SHORTWAVE TROUGH CROSSING WYOMING AT
THIS TIME. SFC COLD FRONT IT MAKING ITS WAY THROUGH THE EASTERN
CWA AND IS ALMOST AT THE SD/MN BORDER. AREA OF RAIN MOVING
NORTHEAST ACROSS SOUTH CENTRAL SD. MADE A FEW CHANGES TO THE
FORECAST FOR TODAY BASED ON CURRENT MODEL AND RADAR TRENDS. FIRST
OFF...SEVERE THREAT LOOKS TO BE EAST OF THE CWA TODAY AND LATEST
DAY ONE SEVERE OUTLOOK HAS SHIFTED EAST. FRONTAL PASSAGE SPEED
LIKELY PUTS BEST SEVERE POTENTIAL FROM MINNESOTA THROUGH IOWA AND
INTO NEBRASKA. HAVING SAID THAT THOUGH...STILL EXPECTING
ADDITIONAL SHOWER AND STORM DEVELOPMENT ACROSS WESTERN/CENTRAL SD
LATER THIS AFTERNOON...THEN SPREADING EAST INTO THE EVENING.
MODELS PICKING UP ON THIS...AND HRRR ACTUALLY HAVING A GOOD
REPRESENTATION OF CURRENT CONDITIONS AND MAY BE LATCHING ONTO
SOMETHING FOR LATER TODAY. BASICALLY...IT WOULD APPEAR MUCH OF THE
CWA IS QUIET TODAY...ESPECIALLY THE NORTHEAST. BUT BY THIS
AFTERNOON AND EVENING COULD SEE AN INCREASE IN SHOWER AND STORM
COVERAGE. ADJUSTED POPS ACCORDINGLY BUT STILL SOME UNCERTAINTY
HERE. NEED TO WATCH AREA OF RAIN MOVING TOWARDS PIERRE TO SEE IF
IT HOLDS TOGETHER OR EXPANDS. CONCERNING TODAYS TEMPS...ANOTHER
GREY AREA AS ABUNDANT MID LEVEL CLOUDS STREAMING INTO THE REGION
MAY KEEP TEMPS DOWN A FEW DEGREES. ALSO DEALING WITH A STRATUS
DECK OVER THE NORTHERN CWA IN WHICH ITS RESIDENT TIME OVER THE
AREA IS QUESTIONABLE. FURTHER ADJUSTMENTS TO POPS/TEMPS LIKELY
NEEDED THROUGHOUT THE DAY.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH TUESDAY
WARM ADVECTION/LOW LEVEL JET LINE OF STORMS PUSHING RAPIDLY TO THE
EAST/NORTHEAST. THE SURFACE LOW IS POSITIONED BACK TOWARDS THE MO
RIVER...AND THE UPPER TROF AXIS IS POSITIONED BACK IN WY. WHILE
THE SURFACE LOW/TROF IS EXPECTED TO PUSH INTO THE FAR EASTERN
CWA...COOLER AIR ALOFT WILL HELP DESTABILIZE THE ATMOSPHERE ACROSS
THE REGION. THE FAR EASTERN CWA WILL CONTINUE TO SEE A FAVORABLE
SHEAR PROFILE FOR SEVERE WEATHER...AND THE REST OF THE CWA WILL
REMAIN CONVECTIVELY UNSTABLE. LOSS TO DAYTIME HEATING WILL REMOVE
THE THREAT OF STORMS...HOWEVER CLOUDS AND LIGHT SHOWERS MAY
PERSIST AS THE UPPER TROF REMAINS OVERHEAD. A SECONDARY SHORTWAVE
MOVES IN MONDAY EVENING...WITH ANOTHER ROUND OF CONVECTION.
AS FOR TEMPERATURES...LOOK FOR HIGHS IN THE 70S BOTH TODAY AND
MONDAY. TUESDAY WILL SEE WARMER READINGS UNDER A WARM ADVECTION
REGIME.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
THE MODELS AGREE WELL IN THE LONG TERM WITH KEEPING IT MAINLY DRY
ALONG WITH A COOL DOWN. THE PERIOD BEGINS WITH AN UPPER LOW PRESSURE
TROUGH DROPPING INTO THE PACIFIC NORTHWEST ON TUESDAY NIGHT. THIS
THEN TRACKS ALONG THE CANADIAN BORDER INTO THURSDAY. AT THE
SURFACE...A LOW PRESSURE AREA AND COOL FRONT SWEEP FROM NORTHWEST
TO SOUTHEAST ACROSS OUR REGION FROM TUESDAY NIGHT INTO THURSDAY.
THUS...WARMER AIR AND SUNSHINE IN ADVANCE OF THIS WILL BRING ABOVE
NORMAL TEMPERATURES TO THE CWA FOR WEDNESDAY WITH HIGHS IN THE 80S
TO AROUND 90 DEGREES IN THE SOUTHWEST CWA. AS THE SURFACE LOW PRESSURE
AREA/COOL FRONT PUSH ACROSS THE REGION FOR THURSDAY INTO FRIDAY...
TEMPERATURES WILL COOL TO MAINLY THE 70S FOR FRIDAY CONTINUING
INTO SATURDAY. SURFACE HIGH PRESSURE LOOKS TO BE IN CONTROL OF THE
WEATHER FROM THURSDAY THROUGH SATURDAY. HAVE IN A FEW CHANCES OF
SHOWERS/STORMS THROUGH THE PERIOD MAINLY EARLY WITH THE SURFACE
LOW AND COOL FRONT.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
WHATEVER LEFTOVER MVFR CIGS ARE HANGING AROUND SHOULD DISSIPATE
THIS AFTERNOON. AN AREA OF RAIN/SHOWERS ASSOCIATED WITH AN MCV IS
LIKELY TO AFFECT KPIR/KATY/KABR THIS AFTERNOON INTO THE EARLY
EVENING HOURS. OVERALL VFR CONDITIONS ARE EXPECTED LATER THIS
AFTERNOON THROUGH TONIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...TMT
SHORT TERM...CONNELLY
LONG TERM...MOHR
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1039 AM CDT SUN AUG 31 2014
.UPDATE...REST OF TODAY
SOMEWHAT DIFFICULT FORECAST SHAPING UP FOR TODAY WITH A FEW
UNCERTAINTIES. FAIRLY POTENT SHORTWAVE TROUGH CROSSING WYOMING AT
THIS TIME. SFC COLD FRONT IT MAKING ITS WAY THROUGH THE EASTERN
CWA AND IS ALMOST AT THE SD/MN BORDER. AREA OF RAIN MOVING
NORTHEAST ACROSS SOUTH CENTRAL SD. MADE A FEW CHANGES TO THE
FORECAST FOR TODAY BASED ON CURRENT MODEL AND RADAR TRENDS. FIRST
OFF...SEVERE THREAT LOOKS TO BE EAST OF THE CWA TODAY AND LATEST
DAY ONE SEVERE OUTLOOK HAS SHIFTED EAST. FRONTAL PASSAGE SPEED
LIKELY PUTS BEST SEVERE POTENTIAL FROM MINNESOTA THROUGH IOWA AND
INTO NEBRASKA. HAVING SAID THAT THOUGH...STILL EXPECTING
ADDITIONAL SHOWER AND STORM DEVELOPMENT ACROSS WESTERN/CENTRAL SD
LATER THIS AFTERNOON...THEN SPREADING EAST INTO THE EVENING.
MODELS PICKING UP ON THIS...AND HRRR ACTUALLY HAVING A GOOD
REPRESENTATION OF CURRENT CONDITIONS AND MAY BE LATCHING ONTO
SOMETHING FOR LATER TODAY. BASICALLY...IT WOULD APPEAR MUCH OF THE
CWA IS QUIET TODAY...ESPECIALLY THE NORTHEAST. BUT BY THIS
AFTERNOON AND EVENING COULD SEE AN INCREASE IN SHOWER AND STORM
COVERAGE. ADJUSTED POPS ACCORDINGLY BUT STILL SOME UNCERTAINTY
HERE. NEED TO WATCH AREA OF RAIN MOVING TOWARDS PIERRE TO SEE IF
IT HOLDS TOGETHER OR EXPANDS. CONCERNING TODAYS TEMPS...ANOTHER
GREY AREA AS ABUNDANT MID LEVEL CLOUDS STREAMING INTO THE REGION
MAY KEEP TEMPS DOWN A FEW DEGREES. ALSO DEALING WITH A STRATUS
DECK OVER THE NORTHERN CWA IN WHICH ITS RESIDENT TIME OVER THE
AREA IS QUESTIONABLE. FURTHER ADJUSTMENTS TO POPS/TEMPS LIKELY
NEEDED THROUGHOUT THE DAY.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...THROUGH TUESDAY
WARM ADVECTION/LOW LEVEL JET LINE OF STORMS PUSHING RAPIDLY TO THE
EAST/NORTHEAST. THE SURFACE LOW IS POSITIONED BACK TOWARDS THE MO
RIVER...AND THE UPPER TROF AXIS IS POSITIONED BACK IN WY. WHILE
THE SURFACE LOW/TROF IS EXPECTED TO PUSH INTO THE FAR EASTERN
CWA...COOLER AIR ALOFT WILL HELP DESTABILIZE THE ATMOSPHERE ACROSS
THE REGION. THE FAR EASTERN CWA WILL CONTINUE TO SEE A FAVORABLE
SHEAR PROFILE FOR SEVERE WEATHER...AND THE REST OF THE CWA WILL
REMAIN CONVECTIVELY UNSTABLE. LOSS TO DAYTIME HEATING WILL REMOVE
THE THREAT OF STORMS...HOWEVER CLOUDS AND LIGHT SHOWERS MAY
PERSIST AS THE UPPER TROF REMAINS OVERHEAD. A SECONDARY SHORTWAVE
MOVES IN MONDAY EVENING...WITH ANOTHER ROUND OF CONVECTION.
AS FOR TEMPERATURES...LOOK FOR HIGHS IN THE 70S BOTH TODAY AND
MONDAY. TUESDAY WILL SEE WARMER READINGS UNDER A WARM ADVECTION
REGIME.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
THE MODELS AGREE WELL IN THE LONG TERM WITH KEEPING IT MAINLY DRY
ALONG WITH A COOL DOWN. THE PERIOD BEGINS WITH AN UPPER LOW PRESSURE
TROUGH DROPPING INTO THE PACIFIC NORTHWEST ON TUESDAY NIGHT. THIS
THEN TRACKS ALONG THE CANADIAN BORDER INTO THURSDAY. AT THE
SURFACE...A LOW PRESSURE AREA AND COOL FRONT SWEEP FROM NORTHWEST
TO SOUTHEAST ACROSS OUR REGION FROM TUESDAY NIGHT INTO THURSDAY.
THUS...WARMER AIR AND SUNSHINE IN ADVANCE OF THIS WILL BRING ABOVE
NORMAL TEMPERATURES TO THE CWA FOR WEDNESDAY WITH HIGHS IN THE 80S
TO AROUND 90 DEGREES IN THE SOUTHWEST CWA. AS THE SURFACE LOW PRESSURE
AREA/COOL FRONT PUSH ACROSS THE REGION FOR THURSDAY INTO FRIDAY...
TEMPERATURES WILL COOL TO MAINLY THE 70S FOR FRIDAY CONTINUING
INTO SATURDAY. SURFACE HIGH PRESSURE LOOKS TO BE IN CONTROL OF THE
WEATHER FROM THURSDAY THROUGH SATURDAY. HAVE IN A FEW CHANCES OF
SHOWERS/STORMS THROUGH THE PERIOD MAINLY EARLY WITH THE SURFACE
LOW AND COOL FRONT.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
WINDS WILL COME AROUND TO THE SOUTHWEST AND WEST AND INCREASE THIS
MORNING BEHIND A SURFACE LOW PRESSURE AREA MOVING ACROSS NORTHEAST
SD. OTHERWISE...AN UPPER LEVEL LOW PRESSURE TROUGH OUT WEST WILL
BE MOVING INTO THE REGION TODAY. THIS WILL SPREAD IN VFR MID LEVEL
CLOUDS ALONG WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FOR
LATE THIS MORNING INTO THE EARLY EVENING. INSERTED SOME VICINITY
SHOWERS IN FOR ALL LOCATIONS AT THIS TIME. THE CLOUDS AND
PRECIPITATION WILL MOVE OFF TO THE EAST THIS EVENING WITH WINDS
BECOMING LIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...TMT
SHORT TERM...CONNELLY
LONG TERM...MOHR
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
251 PM EDT SUN AUG 31 2014
.SHORT TERM...(TONIGHT THROUGH TUESDAY)...AIR MASS WAS SLUGGISH TO
DE-STABILIZE THIS AFTERNOON DUE TO EXTENSIVE CLOUD COVER. HOWEVER
STARTING TO SEE SCATTERED CONVECTION (SOMEWHAT STRONG) DEVELOP
OVER NE AL AND SRN PLATEAU...WHERE MESO PAGE SHOWS 30 KTS OF SHEAR.
BASED ON THIS NEW ACTIVITY WENT IN LINE WITH LATEST HRRR AND RAP
MODELS. THUS...KEPT A SLIVER OF LIKELY POPS FOR LATE AFTERNOON
ACROSS SEQUATCHIE VALLEY AND NRN PLATEAU COUNTIES.
OTHERWISE...FOR THIS EVENING...CARRIED CHANCE POPS FROM W TO E
ACROSS THE FORECAST AREA WITH HIGHER CHANCES WEST. DROPPED BACK TO
MOSTLY SLIGHT CHANCE POPS AFTER MIDNIGHT AND ALLOWED FOR PATCHY FOG
AREAWIDE LATE.
RIDGING IS NOTED BRIEFLY ACROSS THE REGION FOR MONDAY AND MONDAY
NIGHT...BEFORE MODELS ADVERTISE ANOTHER APPROACHING SHORTWAVE FOR
TUESDAY. LOWERED POPS A BIT MORE FOR MONDAY AND CARRIED JUST
MINIMAL POPS IN HIGHER TERRAIN AREAS FOR MONDAY EVENING. CHANCE
POPS FOR NOW ON TUESDAY...MORE LIKELY IN THE AFTERNOON. I THINK
FOG COULD BE MORE OF AN ISSUE MONDAY NIGHT GIVEN AN APPARENT LACK
OF CONVECTIVE DEBRIS CLOUDS.
FOR TEMPS...MOS MINS CLOSE AND GENERALLY FOLLOWED. FAVORED THE
WARMER MAXES MONDAY AND STAYED A BIT BELOW THE WARMER GFS MAXES ON
TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)...A WEAK FRONTAL BOUNDARY
IS PROGGED TO DROP SOUTH ACROSS THE VIEWING AREA WEDNESDAY INTO
THURSDAY GENERATING A LITTLE BETTER CHANCE FOR SOME SHOWERS AND
THUNDERSTORMS ACROSS THE REGION. THE MODELS DON`T SHOW MUCH DRYING
AND STABILIZING BEHIND THIS WEAK FEATURE SO KEPT CHANCE POPS FOR
CONVECTION GOING AREA WIDE ON FRIDAY AND SATURDAY. ANOTHER LOW
AMPLITUDE UPPER TROUGH PASSAGE ACROSS THE NORTHEASTERN QUARTER OF
THE COUNTRY HAS BEEN MODELED FOR LATE IN THE WEEKEND SO RAISED POPS
IN THE CHANCE CATEGORY FOR SUNDAY AS A SURFACE COOL FRONTAL BOUNDARY
ACCOMPANIES THE UPPER FEATURE.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 69 93 71 92 / 30 20 10 30
KNOXVILLE MCGHEE TYSON AIRPORT, TN 69 90 69 90 / 30 10 10 30
OAK RIDGE, TN 68 91 69 90 / 40 10 10 30
TRI CITIES AIRPORT, TN 66 90 63 89 / 30 10 10 30
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
950 AM EDT SUN AUG 31 2014
.DISCUSSION...CHALLENGE FOR FORECAST THIS MORNING IS HOW FAR EAST
THE STEADY STREAM OF SHOWERS AND TSRA SPREAD...AS THE SHORTWAVE
TROUGH TO OUR NORTH TRACKS ACROSS THE GREAT LAKES AND OHIO VALLEY.
THE SHORT RANGE MODELS...MAINLY THE HRRR AND RAP...SEEM MORE
REASONABLE IN KEEPING THE BEST COVERAGE ACROSS OUR WRN COUNIES.
FORECAST GRIDS GENERALLY IN LINE WITH THIS SCENARIO...BUT WILL
MONITOR RADAR DEVELOPMENTS FOR THE REST OF THE MORNING.
EXTENSIVE CLOUD COVER COULD HINDER MAX TEMPS THIS AFTERNOON...ALTHO
MIN TEMPS WERE VERY MILD...SO REACHING 80S TO NEAR 90 DEGREES IS
QUITE POSSIBLE.
FORECAST GRIDS AND PRODUCTS LOOK GOOD WITH NO UPDATES NEEDED UNLESS
THE SHOWERS WORK FURTHER EAST OF I-75 AND I-81...WHERE SCATTERED
WORDING AND HIGH CHANCE POPS ARE FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 88 70 93 71 / 50 30 20 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 87 69 91 69 / 50 30 20 10
OAK RIDGE, TN 87 69 91 69 / 60 30 20 10
TRI CITIES AIRPORT, TN 86 66 87 63 / 50 40 20 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
111 PM CDT SUN AUG 31 2014
.DISCUSSION...
18Z AVIATION DISCUSSION.
&&
.AVIATION...
A BROAD LIGHT RAIN SHIELD WITH EMBEDDED STORMS EXTENDING FROM THE
MATAGORDA BAY REGION COUNTIES NORTHEAST ACROSS NORTHERN GALVESTON
BAY AND INTO THE PINEY WOODS...MORE DISCRETE CELLS PASSING ACROSS
KUTS AND KCLL THIS HOUR. RAIN WILL BE ENDING THROUGH THE DAY...THIS
LULL WILL PERSIST THROUGH EARLY MONDAY MORNING WHERE RETURN NEAR-
COASTAL/GULF PRECIPITATION RE-DEVELOPS AND MOVES INLAND PAST SUNRISE.
IF NOT WITHIN RAINS/STORM...VFR CEILINGS/VSBY. PERIODS OF OVERNIGHT
MVFR/IFR DECKS...OR VSBY-REDUCING HZ/FOG...OVER MORE RURAL AREAS
DUE TO A WEAK WIND AND WET GROUND. AREAL SHRA/TSRA COVERAGE MAY
NOT BE AS WIDESPREAD AS TODAY...BUT THE FORECAST IS FOR RETURN
MORE DISCRETE CELLS LATE MONDAY MORNING INTO EARLY AFTERNOON
ACTIVITY...OR AS SOUTHERN COUNTY CONVECTION ADVANCES INTO A MID-
UPPER 80F WARMED INTERIOR AIR MASS. 31
&&
.PREV DISCUSSION... /ISSUED 1014 AM CDT SUN AUG 31 2014/
UPDATE...
SEE MORNING UPDATE.
DISCUSSION...
AT 9 AM...A WEAK TROUGH OR PERHAPS AN OUTFLOW EXTENDS FROM ABOUT
LEAGUE CITY TOM PALACIOS. MOISTURE IS PLENTIFUL AT 850 MB WITH DEW
PTS AT 16-17 C. AT 700 MB...A WEAK TROUGH EXTENDED FROM ABOUT
WHARTON TO MCALLEN WITH A WELL DEFINED 700 MB TROUGH AXIS
EXTENDING FROM ABOUT ST LOUIS TO TEXARKANA TO AUSTIN. AT 250
MB...A WELL DEFINED TROUGH AXIS EXTENDS FROM SE OK INTO CENTRAL
TEXAS. THE LIFT PROVIDED BY THE MID LEVEL TROUGHS AND DEEP
MOISTURE WILL SET THE STAGE FOR ADDITIONAL SHRA/TSRA THROUGH THE
MORNING. 12Z SOUNDINGS SHOW PW VALUES BETWEEN 2.2 AND 2.3
INCHES...NO CAPPING AND CONVECTIVE TEMPS IN LOWER 80S. RADAR IS
SHOWING A SWATH OF RAINFALL MAINLY ALONG AND EAST OF US HWY 59.
1 TO 3 INCHES OF RAIN HAS FALLEN OVER PARTS OF MATAGORDA AND
BRAZORIA COUNTIES WITH A BIT MORE ON THE WAY THIS MORNING. MODELS
INITIALIZED FAIRLY WELL SO AM EXPECTING THE RAINFALL TO CONTINUE
TO MOVE EAST AND NORTH THROUGH THE MORNING WITH RAINFALL BEGINNING
TO DIMINISH BY EARLY THIS AFTN. CURRENT FCST LOOKS ON TRACK BUT
MAY TWEAK TEMPS DOWN A BIT IN THE RAIN COOLED AIR. 43
&&
PREV DISCUSSION... /ISSUED 644 AM CDT SUN AUG 31 2014/
DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION.
AVIATION...
BAND OF SHRA WITH A FEW ISOLATED TSRA EMBEDDED CONTINUES TO LIFT
SLOWLY NORTHWARD ALONG THE US 59 CORRIDOR. HI RES MODELS INDICATE
THIS ACTIVITY WILL CONTINUE TO SPREAD NORTHWARD THROUGH THE DAY
AND FILL IN FURTHER EAST. BEST COVERAGE AND TSRA CHANCES LOOK TO
REMAIN ALONG AND WEST OF INTERSTATE 45 WITH COVERAGE DIMINISHING
BY LATE AFTERNOON. LOW CLOUDS REDEVELOP AFTER MIDNIGHT WITH MVFR
CIGS POSSIBLE BY DAYBREAK ON MONDAY. 38
&&
PREV DISCUSSION... /ISSUED 439 AM CDT SUN AUG 31 2014/
DISCUSSION...
ALTHOUGH THERE WAS PLENTY OF TROPICAL MOISTURE AND LIFT FROM AN
UPPER LEVEL TROUGH AXIS...THE MAJORITY OF CONVECTION FORMED IN THE
GULF OF MEXICO AND MOVED INTO E TX AND SW LA. LAKE CHARLES ENDED
UP WITH 7.87 INCHES OF RAIN FOR YESTERDAY. THERE IS A SIMILAR
ENVIRONMENT IN PLACE TODAY WITH TROPICAL MOISTURE STILL OVER MUCH
OF SE TX AND UPPER TX COAST. THE TROUGH AXIS IS SLOWLY WEAKENING
BUT STILL COULD BE A FOCUS FOR CONVECTIVE ACTIVITY. BOTH 00Z
LCH/CRP SOUNDINGS SHOWED 2.2 INCHES OF PRECIP WATER AND GOES
SOUNDER DATA ALSO DEPICTS A SWATH OF TROPICAL MOISTURE STRETCHING
SW TO NE ACROSS THE TX COAST. BASED ON WATER VAPOR IMAGERY TROUGH
AXIS SHOULD BE MOVING OUT OF THE AREA AS UPSTREAM SHORT WAVE
TROUGH MOVES ACROSS THE ROCKIES AND INTO THE PLAINS LATER
TODAY/TONIGHT. THIS SHOULD ALSO HELP ADVECT TROPICAL MOISTURE OVER
THE REGION THIS MORNING AND AFTERNOON. HI RES MODELS WRF-
ARW/RAP/HRRR DEVELOP CONVECTION ALONG THE UPPER TX COAST AND MOVE
IT INTO THE COASTAL COUNTIES AROUND 12Z THIS MORNING. RADAR
ALREADY SHOWING SOME SHOWER ACTIVITY FROM MATAGORDA BAY AND
OFFSHORE. THIS SEEMS TO BE MATCHING THE TRENDS IN THE SHORT RANGE
HI RES MODELS. THE NAM/GFS/ECMWF ALSO SUPPORT THE IDEA OF A SWATH
OF PRECIP EMBEDDED WITHIN MAIN TROPICAL MOISTURE AXIS. DECIDED TO
KEEP MENTION OF 60 POPS. AGAIN WITH THIS MUCH MOISTURE STRONGER
STORMS WILL BE CAPABLE OF 1-2 INCHES OF RAIN AN HOUR. ACCUMULATED
PRECIP TOTALS FROM 06Z HRRR SHOW SWATH OF 2-4 INCHES OF RAIN BY
21Z THIS AFTERNOON SO ISOLATED HIGHER AMOUNTS OF RAIN WILL BE
POSSIBLE. MODELS DO INDICATE RAINFALL COMING TO AN END LATE
AFTERNOON AND EVENING SO DECREASED RAIN CHANCES FOR THE AFTERNOON.
OVERALL MOISTURE TRENDS IN NAM/GFS KEEP NEARLY 2 INCHES OF PRECIP
WATER OVER THE TX COAST THROUGH THE MIDDLE OF THE WEEK. A TROPICAL
WAVE IN THE NW CARIBBEAN SHOULD BE MOVING ACROSS THE YUCATAN TODAY
AND TOMORROW. NHC GIVES THIS WAVE A 50 PERCENT CHANCE OF BECOMING
A TROPICAL CYCLONE OVER NEXT 5 DAYS. ITS BEST CHANCE TO DO SO PER
LATEST MODEL GUIDANCE WILL NOT BE UNTIL IT EMERGES IN THE GULF.
EVEN THEN ONLY THE NAM REALLY DEVELOPS THE SYSTEM INTO A CLOSED
CIRCULATION. THE GFS/ECMWF KEEP IT AS AN OPEN WAVE WHICH HAS BEEN
WAY MORE CONSISTENT THAN THE NAM. OVERALL IMPACT TO TX WILL BE TO
KEEP A FETCH OF DEEP MOISTURE OFF THE GULF IN PLACE. THIS SHOULD
ALLOW FOR DAILY RAIN CHANCES FOR THE NEXT WEEK WITH DAY TIME
HEATING DRIVING CONVECTIVE TRENDS. COVERAGE IN CONVECTION WILL BE
THE REAL ISSUE AS GLOBAL MODELS ESTABLISH A BROAD ELONGATED UPPER
LEVEL RIDGE OVER MUCH OF THE SOUTHERN U.S. THE STRENGTH OF THE
RIDGE IS ALSO A QUESTION SO DIFFICULT TO GAGE HOW MUCH SUBSIDENCE
WILL BE OCCURRING DUE TO THE RIDGE. WITH THESE FACTORS IN MIND THE
FORECAST WILL KEEP AT LEAST SOME MENTION OF THUNDERSTORMS EACH
DAY. IT LOOKS LIKE THE HIGHER RAIN CHANCES WILL BE TUE/WED AS THIS
IS WHEN TROPICAL MOISTURE FROM THE TROPICAL WAVE MAY IMPACT THE
AREA. FORECAST WILL GO WITH 30/40 POPS FOR THESE DAYS WITH 20 POPS
FOR THE REST OF THE WEEK.
TEMPERATURES FOR THE WEEK WILL BE ABOVE NORMAL BUT STILL THE MORE
TYPICAL SUMMER TIME TEMPERATURES. MIN TEMPS IN THE MID/UPPER 70S
WILL BE EXPECTED WITH MAX TEMPS IN THE LOW/MID 90S. TEMPS WILL BE
GREATLY INFLUENCED BY CONVECTION AND RESULTING CLOUD COVER. AS IT
STANDS...WITH 100F NOT EXPECTED FOR A HIGH TEMPERATURE AT KCLL OR
KIAH TODAY...THE STREAK OF NOT REACHING 100F FOR A HIGH
TEMPERATURE CONTINUES INTO SEPTEMBER. HOPEFULLY IT STAYS THAT WAY
FOR THE REST OF THE YEAR. 39
&&
MARINE...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
MORNING ACROSS THE COASTAL WATERS AS DEEP TROPICAL MOISTURE MOVES
BACK INTO THE REGION. EXPECT ONSHORE FLOW TO PERSIST THROUGH MUCH
OF THE UPCOMING WEEK. WIND SPEEDS WILL INCREASE LATE MONDAY NIGHT
INTO TUESDAY AND CAUTION FLAGS MAY BE NEEDED FOR THE COASTAL
WATERS. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 76 95 76 95 76 / 10 20 10 20 10
HOUSTON (IAH) 77 93 77 93 77 / 10 30 20 30 10
GALVESTON (GLS) 81 89 82 89 81 / 10 30 30 40 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1014 AM CDT SUN AUG 31 2014
.UPDATE...
SEE MORNING UPDATE.
&&
.DISCUSSION...
AT 9 AM...A WEAK TROUGH OR PERHAPS AN OUTFLOW EXTENDS FROM ABOUT
LEAGUE CITY TOM PALACIOS. MOISTURE IS PLENTIFUL AT 850 MB WITH DEW
PTS AT 16-17 C. AT 700 MB...A WEAK TROUGH EXTENDED FROM ABOUT
WHARTON TO MCALLEN WITH A WELL DEFINED 700 MB TROUGH AXIS
EXTENDING FROM ABOUT ST LOUIS TO TEXARKANA TO AUSTIN. AT 250
MB...A WELL DEFINED TROUGH AXIS EXTENDS FROM SE OK INTO CENTRAL
TEXAS. THE LIFT PROVIDED BY THE MID LEVEL TROUGHS AND DEEP
MOISTURE WILL SET THE STAGE FOR ADDITIONAL SHRA/TSRA THROUGH THE
MORNING. 12Z SOUNDINGS SHOW PW VALUES BETWEEN 2.2 AND 2.3
INCHES...NO CAPPING AND CONVECTIVE TEMPS IN LOWER 80S. RADAR IS
SHOWING A SWATH OF RAINFALL MAINLY ALONG AND EAST OF US HWY 59.
1 TO 3 INCHES OF RAIN HAS FALLEN OVER PARTS OF MATAGORDA AND
BRAZORIA COUNTIES WITH A BIT MORE ON THE WAY THIS MORNING. MODELS
INITIALIZED FAIRLY WELL SO AM EXPECTING THE RAINFALL TO CONTINUE
TO MOVE EAST AND NORTH THROUGH THE MORNING WITH RAINFALL BEGINNING
TO DIMINISH BY EARLY THIS AFTN. CURRENT FCST LOOKS ON TRACK BUT
MAY TWEAK TEMPS DOWN A BIT IN THE RAIN COOLED AIR. 43
&&
.PREV DISCUSSION... /ISSUED 644 AM CDT SUN AUG 31 2014/
DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION.
AVIATION...
BAND OF SHRA WITH A FEW ISOLATED TSRA EMBEDDED CONTINUES TO LIFT
SLOWLY NORTHWARD ALONG THE US 59 CORRIDOR. HI RES MODELS INDICATE
THIS ACTIVITY WILL CONTINUE TO SPREAD NORTHWARD THROUGH THE DAY
AND FILL IN FURTHER EAST. BEST COVERAGE AND TSRA CHANCES LOOK TO
REMAIN ALONG AND WEST OF INTERSTATE 45 WITH COVERAGE DIMINISHING
BY LATE AFTERNOON. LOW CLOUDS REDEVELOP AFTER MIDNIGHT WITH MVFR
CIGS POSSIBLE BY DAYBREAK ON MONDAY. 38
PREV DISCUSSION... /ISSUED 439 AM CDT SUN AUG 31 2014/
DISCUSSION...
ALTHOUGH THERE WAS PLENTY OF TROPICAL MOISTURE AND LIFT FROM AN
UPPER LEVEL TROUGH AXIS...THE MAJORITY OF CONVECTION FORMED IN THE
GULF OF MEXICO AND MOVED INTO E TX AND SW LA. LAKE CHARLES ENDED
UP WITH 7.87 INCHES OF RAIN FOR YESTERDAY. THERE IS A SIMILAR
ENVIRONMENT IN PLACE TODAY WITH TROPICAL MOISTURE STILL OVER MUCH
OF SE TX AND UPPER TX COAST. THE TROUGH AXIS IS SLOWLY WEAKENING
BUT STILL COULD BE A FOCUS FOR CONVECTIVE ACTIVITY. BOTH 00Z
LCH/CRP SOUNDINGS SHOWED 2.2 INCHES OF PRECIP WATER AND GOES
SOUNDER DATA ALSO DEPICTS A SWATH OF TROPICAL MOISTURE STRETCHING
SW TO NE ACROSS THE TX COAST. BASED ON WATER VAPOR IMAGERY TROUGH
AXIS SHOULD BE MOVING OUT OF THE AREA AS UPSTREAM SHORT WAVE
TROUGH MOVES ACROSS THE ROCKIES AND INTO THE PLAINS LATER
TODAY/TONIGHT. THIS SHOULD ALSO HELP ADVECT TROPICAL MOISTURE OVER
THE REGION THIS MORNING AND AFTERNOON. HI RES MODELS WRF-
ARW/RAP/HRRR DEVELOP CONVECTION ALONG THE UPPER TX COAST AND MOVE
IT INTO THE COASTAL COUNTIES AROUND 12Z THIS MORNING. RADAR
ALREADY SHOWING SOME SHOWER ACTIVITY FROM MATAGORDA BAY AND
OFFSHORE. THIS SEEMS TO BE MATCHING THE TRENDS IN THE SHORT RANGE
HI RES MODELS. THE NAM/GFS/ECMWF ALSO SUPPORT THE IDEA OF A SWATH
OF PRECIP EMBEDDED WITHIN MAIN TROPICAL MOISTURE AXIS. DECIDED TO
KEEP MENTION OF 60 POPS. AGAIN WITH THIS MUCH MOISTURE STRONGER
STORMS WILL BE CAPABLE OF 1-2 INCHES OF RAIN AN HOUR. ACCUMULATED
PRECIP TOTALS FROM 06Z HRRR SHOW SWATH OF 2-4 INCHES OF RAIN BY
21Z THIS AFTERNOON SO ISOLATED HIGHER AMOUNTS OF RAIN WILL BE
POSSIBLE. MODELS DO INDICATE RAINFALL COMING TO AN END LATE
AFTERNOON AND EVENING SO DECREASED RAIN CHANCES FOR THE AFTERNOON.
OVERALL MOISTURE TRENDS IN NAM/GFS KEEP NEARLY 2 INCHES OF PRECIP
WATER OVER THE TX COAST THROUGH THE MIDDLE OF THE WEEK. A TROPICAL
WAVE IN THE NW CARIBBEAN SHOULD BE MOVING ACROSS THE YUCATAN TODAY
AND TOMORROW. NHC GIVES THIS WAVE A 50 PERCENT CHANCE OF BECOMING
A TROPICAL CYCLONE OVER NEXT 5 DAYS. ITS BEST CHANCE TO DO SO PER
LATEST MODEL GUIDANCE WILL NOT BE UNTIL IT EMERGES IN THE GULF.
EVEN THEN ONLY THE NAM REALLY DEVELOPS THE SYSTEM INTO A CLOSED
CIRCULATION. THE GFS/ECMWF KEEP IT AS AN OPEN WAVE WHICH HAS BEEN
WAY MORE CONSISTENT THAN THE NAM. OVERALL IMPACT TO TX WILL BE TO
KEEP A FETCH OF DEEP MOISTURE OFF THE GULF IN PLACE. THIS SHOULD
ALLOW FOR DAILY RAIN CHANCES FOR THE NEXT WEEK WITH DAY TIME
HEATING DRIVING CONVECTIVE TRENDS. COVERAGE IN CONVECTION WILL BE
THE REAL ISSUE AS GLOBAL MODELS ESTABLISH A BROAD ELONGATED UPPER
LEVEL RIDGE OVER MUCH OF THE SOUTHERN U.S. THE STRENGTH OF THE
RIDGE IS ALSO A QUESTION SO DIFFICULT TO GAGE HOW MUCH SUBSIDENCE
WILL BE OCCURRING DUE TO THE RIDGE. WITH THESE FACTORS IN MIND THE
FORECAST WILL KEEP AT LEAST SOME MENTION OF THUNDERSTORMS EACH
DAY. IT LOOKS LIKE THE HIGHER RAIN CHANCES WILL BE TUE/WED AS THIS
IS WHEN TROPICAL MOISTURE FROM THE TROPICAL WAVE MAY IMPACT THE
AREA. FORECAST WILL GO WITH 30/40 POPS FOR THESE DAYS WITH 20 POPS
FOR THE REST OF THE WEEK.
TEMPERATURES FOR THE WEEK WILL BE ABOVE NORMAL BUT STILL THE MORE
TYPICAL SUMMER TIME TEMPERATURES. MIN TEMPS IN THE MID/UPPER 70S
WILL BE EXPECTED WITH MAX TEMPS IN THE LOW/MID 90S. TEMPS WILL BE
GREATLY INFLUENCED BY CONVECTION AND RESULTING CLOUD COVER. AS IT
STANDS...WITH 100F NOT EXPECTED FOR A HIGH TEMPERATURE AT KCLL OR
KIAH TODAY...THE STREAK OF NOT REACHING 100F FOR A HIGH
TEMPERATURE CONTINUES INTO SEPTEMBER. HOPEFULLY IT STAYS THAT WAY
FOR THE REST OF THE YEAR.
39
MARINE...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
MORNING ACROSS THE COASTAL WATERS AS DEEP TROPICAL MOISTURE MOVES
BACK INTO THE REGION. EXPECT ONSHORE FLOW TO PERSIST THROUGH MUCH
OF THE UPCOMING WEEK. WIND SPEEDS WILL INCREASE LATE MONDAY NIGHT
INTO TUESDAY AND CAUTION FLAGS MAY BE NEEDED FOR THE COASTAL
WATERS. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 94 76 95 76 95 / 20 10 20 10 20
HOUSTON (IAH) 91 77 93 77 93 / 60 10 30 20 30
GALVESTON (GLS) 88 81 89 82 89 / 60 10 30 30 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
644 AM CDT SUN AUG 31 2014
.DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION.
&&
.AVIATION...
BAND OF SHRA WITH A FEW ISOLATED TSRA EMBEDDED CONTINUES TO LIFT
SLOWLY NORTHWARD ALONG THE US 59 CORRIDOR. HI RES MODELS INDICATE
THIS ACTIVITY WILL CONTINUE TO SPREAD NORTHWARD THROUGH THE DAY
AND FILL IN FURTHER EAST. BEST COVERAGE AND TSRA CHANCES LOOK TO
REMAIN ALONG AND WEST OF INTERSTATE 45 WITH COVERAGE DIMINISHING
BY LATE AFTERNOON. LOW CLOUDS REDEVELOP AFTER MIDNIGHT WITH MVFR
CIGS POSSIBLE BY DAYBREAK ON MONDAY. 38
&&
.PREV DISCUSSION... /ISSUED 439 AM CDT SUN AUG 31 2014/
DISCUSSION...
ALTHOUGH THERE WAS PLENTY OF TROPICAL MOISTURE AND LIFT FROM AN
UPPER LEVEL TROUGH AXIS...THE MAJORITY OF CONVECTION FORMED IN THE
GULF OF MEXICO AND MOVED INTO E TX AND SW LA. LAKE CHARLES ENDED
UP WITH 7.87 INCHES OF RAIN FOR YESTERDAY. THERE IS A SIMILAR
ENVIRONMENT IN PLACE TODAY WITH TROPICAL MOISTURE STILL OVER MUCH
OF SE TX AND UPPER TX COAST. THE TROUGH AXIS IS SLOWLY WEAKENING
BUT STILL COULD BE A FOCUS FOR CONVECTIVE ACTIVITY. BOTH 00Z
LCH/CRP SOUNDINGS SHOWED 2.2 INCHES OF PRECIP WATER AND GOES
SOUNDER DATA ALSO DEPICTS A SWATH OF TROPICAL MOISTURE STRETCHING
SW TO NE ACROSS THE TX COAST. BASED ON WATER VAPOR IMAGERY TROUGH
AXIS SHOULD BE MOVING OUT OF THE AREA AS UPSTREAM SHORT WAVE
TROUGH MOVES ACROSS THE ROCKIES AND INTO THE PLAINS LATER
TODAY/TONIGHT. THIS SHOULD ALSO HELP ADVECT TROPICAL MOISTURE OVER
THE REGION THIS MORNING AND AFTERNOON. HI RES MODELS WRF-
ARW/RAP/HRRR DEVELOP CONVECTION ALONG THE UPPER TX COAST AND MOVE
IT INTO THE COASTAL COUNTIES AROUND 12Z THIS MORNING. RADAR
ALREADY SHOWING SOME SHOWER ACTIVITY FROM MATAGORDA BAY AND
OFFSHORE. THIS SEEMS TO BE MATCHING THE TRENDS IN THE SHORT RANGE
HI RES MODELS. THE NAM/GFS/ECMWF ALSO SUPPORT THE IDEA OF A SWATH
OF PRECIP EMBEDDED WITHIN MAIN TROPICAL MOISTURE AXIS. DECIDED TO
KEEP MENTION OF 60 POPS. AGAIN WITH THIS MUCH MOISTURE STRONGER
STORMS WILL BE CAPABLE OF 1-2 INCHES OF RAIN AN HOUR. ACCUMULATED
PRECIP TOTALS FROM 06Z HRRR SHOW SWATH OF 2-4 INCHES OF RAIN BY
21Z THIS AFTERNOON SO ISOLATED HIGHER AMOUNTS OF RAIN WILL BE
POSSIBLE. MODELS DO INDICATE RAINFALL COMING TO AN END LATE
AFTERNOON AND EVENING SO DECREASED RAIN CHANCES FOR THE AFTERNOON.
OVERALL MOISTURE TRENDS IN NAM/GFS KEEP NEARLY 2 INCHES OF PRECIP
WATER OVER THE TX COAST THROUGH THE MIDDLE OF THE WEEK. A TROPICAL
WAVE IN THE NW CARIBBEAN SHOULD BE MOVING ACROSS THE YUCATAN TODAY
AND TOMORROW. NHC GIVES THIS WAVE A 50 PERCENT CHANCE OF BECOMING
A TROPICAL CYCLONE OVER NEXT 5 DAYS. ITS BEST CHANCE TO DO SO PER
LATEST MODEL GUIDANCE WILL NOT BE UNTIL IT EMERGES IN THE GULF.
EVEN THEN ONLY THE NAM REALLY DEVELOPS THE SYSTEM INTO A CLOSED
CIRCULATION. THE GFS/ECMWF KEEP IT AS AN OPEN WAVE WHICH HAS BEEN
WAY MORE CONSISTENT THAN THE NAM. OVERALL IMPACT TO TX WILL BE TO
KEEP A FETCH OF DEEP MOISTURE OFF THE GULF IN PLACE. THIS SHOULD
ALLOW FOR DAILY RAIN CHANCES FOR THE NEXT WEEK WITH DAY TIME
HEATING DRIVING CONVECTIVE TRENDS. COVERAGE IN CONVECTION WILL BE
THE REAL ISSUE AS GLOBAL MODELS ESTABLISH A BROAD ELONGATED UPPER
LEVEL RIDGE OVER MUCH OF THE SOUTHERN U.S. THE STRENGTH OF THE
RIDGE IS ALSO A QUESTION SO DIFFICULT TO GAGE HOW MUCH SUBSIDENCE
WILL BE OCCURRING DUE TO THE RIDGE. WITH THESE FACTORS IN MIND THE
FORECAST WILL KEEP AT LEAST SOME MENTION OF THUNDERSTORMS EACH
DAY. IT LOOKS LIKE THE HIGHER RAIN CHANCES WILL BE TUE/WED AS THIS
IS WHEN TROPICAL MOISTURE FROM THE TROPICAL WAVE MAY IMPACT THE
AREA. FORECAST WILL GO WITH 30/40 POPS FOR THESE DAYS WITH 20 POPS
FOR THE REST OF THE WEEK.
TEMPERATURES FOR THE WEEK WILL BE ABOVE NORMAL BUT STILL THE MORE
TYPICAL SUMMER TIME TEMPERATURES. MIN TEMPS IN THE MID/UPPER 70S
WILL BE EXPECTED WITH MAX TEMPS IN THE LOW/MID 90S. TEMPS WILL BE
GREATLY INFLUENCED BY CONVECTION AND RESULTING CLOUD COVER. AS IT
STANDS...WITH 100F NOT EXPECTED FOR A HIGH TEMPERATURE AT KCLL OR
KIAH TODAY...THE STREAK OF NOT REACHING 100F FOR A HIGH
TEMPERATURE CONTINUES INTO SEPTEMBER. HOPEFULLY IT STAYS THAT WAY
FOR THE REST OF THE YEAR.
39
MARINE...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
MORNING ACROSS THE COASTAL WATERS AS DEEP TROPICAL MOISTURE MOVES
BACK INTO THE REGION. EXPECT ONSHORE FLOW TO PERSIST THROUGH MUCH
OF THE UPCOMING WEEK. WIND SPEEDS WILL INCREASE LATE MONDAY NIGHT
INTO TUESDAY AND CAUTION FLAGS MAY BE NEEDED FOR THE COASTAL
WATERS. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 94 76 95 76 95 / 20 10 20 10 20
HOUSTON (IAH) 91 77 93 77 93 / 40 10 30 20 30
GALVESTON (GLS) 88 81 89 82 89 / 60 10 30 30 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...38
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
439 AM CDT SUN AUG 31 2014
.DISCUSSION...
ALTHOUGH THERE WAS PLENTY OF TROPICAL MOISTURE AND LIFT FROM AN
UPPER LEVEL TROUGH AXIS...THE MAJORITY OF CONVECTION FORMED IN THE
GULF OF MEXICO AND MOVED INTO E TX AND SW LA. LAKE CHARLES ENDED
UP WITH 7.87 INCHES OF RAIN FOR YESTERDAY. THERE IS A SIMILAR
ENVIRONMENT IN PLACE TODAY WITH TROPICAL MOISTURE STILL OVER MUCH
OF SE TX AND UPPER TX COAST. THE TROUGH AXIS IS SLOWLY WEAKENING
BUT STILL COULD BE A FOCUS FOR CONVECTIVE ACTIVITY. BOTH 00Z
LCH/CRP SOUNDINGS SHOWED 2.2 INCHES OF PRECIP WATER AND GOES
SOUNDER DATA ALSO DEPICTS A SWATH OF TROPICAL MOISTURE STRETCHING
SW TO NE ACROSS THE TX COAST. BASED ON WATER VAPOR IMAGERY TROUGH
AXIS SHOULD BE MOVING OUT OF THE AREA AS UPSTREAM SHORT WAVE
TROUGH MOVES ACROSS THE ROCKIES AND INTO THE PLAINS LATER
TODAY/TONIGHT. THIS SHOULD ALSO HELP ADVECT TROPICAL MOISTURE OVER
THE REGION THIS MORNING AND AFTERNOON. HI RES MODELS WRF-
ARW/RAP/HRRR DEVELOP CONVECTION ALONG THE UPPER TX COAST AND MOVE
IT INTO THE COASTAL COUNTIES AROUND 12Z THIS MORNING. RADAR
ALREADY SHOWING SOME SHOWER ACTIVITY FROM MATAGORDA BAY AND
OFFSHORE. THIS SEEMS TO BE MATCHING THE TRENDS IN THE SHORT RANGE
HI RES MODELS. THE NAM/GFS/ECMWF ALSO SUPPORT THE IDEA OF A SWATH
OF PRECIP EMBEDDED WITHIN MAIN TROPICAL MOISTURE AXIS. DECIDED TO
KEEP MENTION OF 60 POPS. AGAIN WITH THIS MUCH MOISTURE STRONGER
STORMS WILL BE CAPABLE OF 1-2 INCHES OF RAIN AN HOUR. ACCUMULATED
PRECIP TOTALS FROM 06Z HRRR SHOW SWATH OF 2-4 INCHES OF RAIN BY
21Z THIS AFTERNOON SO ISOLATED HIGHER AMOUNTS OF RAIN WILL BE
POSSIBLE. MODELS DO INDICATE RAINFALL COMING TO AN END LATE
AFTERNOON AND EVENING SO DECREASED RAIN CHANCES FOR THE AFTERNOON.
OVERALL MOISTURE TRENDS IN NAM/GFS KEEP NEARLY 2 INCHES OF PRECIP
WATER OVER THE TX COAST THROUGH THE MIDDLE OF THE WEEK. A TROPICAL
WAVE IN THE NW CARIBBEAN SHOULD BE MOVING ACROSS THE YUCATAN TODAY
AND TOMORROW. NHC GIVES THIS WAVE A 50 PERCENT CHANCE OF BECOMING
A TROPICAL CYCLONE OVER NEXT 5 DAYS. ITS BEST CHANCE TO DO SO PER
LATEST MODEL GUIDANCE WILL NOT BE UNTIL IT EMERGES IN THE GULF.
EVEN THEN ONLY THE NAM REALLY DEVELOPS THE SYSTEM INTO A CLOSED
CIRCULATION. THE GFS/ECMWF KEEP IT AS AN OPEN WAVE WHICH HAS BEEN
WAY MORE CONSISTENT THAN THE NAM. OVERALL IMPACT TO TX WILL BE TO
KEEP A FETCH OF DEEP MOISTURE OFF THE GULF IN PLACE. THIS SHOULD
ALLOW FOR DAILY RAIN CHANCES FOR THE NEXT WEEK WITH DAY TIME
HEATING DRIVING CONVECTIVE TRENDS. COVERAGE IN CONVECTION WILL BE
THE REAL ISSUE AS GLOBAL MODELS ESTABLISH A BROAD ELONGATED UPPER
LEVEL RIDGE OVER MUCH OF THE SOUTHERN U.S. THE STRENGTH OF THE
RIDGE IS ALSO A QUESTION SO DIFFICULT TO GAGE HOW MUCH SUBSIDENCE
WILL BE OCCURRING DUE TO THE RIDGE. WITH THESE FACTORS IN MIND THE
FORECAST WILL KEEP AT LEAST SOME MENTION OF THUNDERSTORMS EACH
DAY. IT LOOKS LIKE THE HIGHER RAIN CHANCES WILL BE TUE/WED AS THIS
IS WHEN TROPICAL MOISTURE FROM THE TROPICAL WAVE MAY IMPACT THE
AREA. FORECAST WILL GO WITH 30/40 POPS FOR THESE DAYS WITH 20 POPS
FOR THE REST OF THE WEEK.
TEMPERATURES FOR THE WEEK WILL BE ABOVE NORMAL BUT STILL THE MORE
TYPICAL SUMMER TIME TEMPERATURES. MIN TEMPS IN THE MID/UPPER 70S
WILL BE EXPECTED WITH MAX TEMPS IN THE LOW/MID 90S. TEMPS WILL BE
GREATLY INFLUENCED BY CONVECTION AND RESULTING CLOUD COVER. AS IT
STANDS...WITH 100F NOT EXPECTED FOR A HIGH TEMPERATURE AT KCLL OR
KIAH TODAY...THE STREAK OF NOT REACHING 100F FOR A HIGH
TEMPERATURE CONTINUES INTO SEPTEMBER. HOPEFULLY IT STAYS THAT WAY
FOR THE REST OF THE YEAR.
39
&&
.MARINE...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
MORNING ACROSS THE COASTAL WATERS AS DEEP TROPICAL MOISTURE MOVES
BACK INTO THE REGION. EXPECT ONSHORE FLOW TO PERSIST THROUGH MUCH
OF THE UPCOMING WEEK. WIND SPEEDS WILL INCREASE LATE MONDAY NIGHT
INTO TUESDAY AND CAUTION FLAGS MAY BE NEEDED FOR THE COASTAL
WATERS. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 94 76 95 76 95 / 20 10 20 10 20
HOUSTON (IAH) 91 77 93 77 93 / 40 10 30 20 30
GALVESTON (GLS) 88 81 89 82 89 / 60 10 30 30 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...38
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
937 PM EDT MON SEP 1 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL REMAIN OVER THE REGION TONIGHT INTO MUCH
OF TUESDAY. A WEAK COLD FRONT TRACKS SOUTHEAST INTO OUR AREA BY
TUESDAY EVENING...BEFORE STALLING ACROSS THE CAROLINAS AND WASHING
OUT ON WEDNESDAY. HIGH PRESSURE SETS BACK UP OVER THE EAST BY
FRIDAY WITH YET ANOTHER COLD FRONT MOVING TOWARD US THIS WEEKEND.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 850 PM EDT MONDAY...
OTHER FOR ISOLATED SHRA/TSRA PASSING ACROSS THE FAR
NORTH...CONVECTION REMAINS LIMITED THIS EVENING AS SOUNDINGS SHOW
WEAK CAPPING ALOFT WITHIN A DEEP WESTERLY FLOW REGIME. THIS ALONG
WITH LACK OF DEEP INSTABILITY SHOULD KEEP THINGS MAINLY QUIET
OVERNIGHT WITH JUST SOME PATCHY FOG IN THE VALLEYS AND PERHAPS OUT
EAST. HOWEVER WITH THE LATEST HRRR TRACKING THE CURRENT ISOLATED
COVERAGE OVER GREENBRIER EAST TOWARD THE SOUTHERN SHENANDOAH
VALLEY...WILL LEAVE IN SOME LOW POPS ACROSS THE EXTREME NORTH SINCE
HEADING INTO SOME DECENT LEFTOVER CAPE DESPITE LOSS OF HEATING.
WILL ALSO CONTINUE SOME LOW CHANCES FAR NW LATE FOR ACTIVITY
COMING IN AHEAD OF THE UPSTREAM FRONT AROUND DAYBREAK. OTRW FEW
CHANGES OTHER THAN TO INCLUDE A BIT OF FOG AND BUMP UP TEMPS IN
SPOTS GIVEN SUCH A MUGGY OVERNIGHT.
ANOTHER SHORTWAVE AHEAD OF A FRONT SHIFTING SE INTO THE OHIO VALLEY
PASSES ACROSS TUESDAY MORNING. FOR NOW IT LOOKS LIKE THE WESTERN CWA
WILL SEE A CHANCE OF SHOWERS/ISOLATED TSRA DURING THE MORNING BUT
AGAIN EAST OF THE BLUE RIDGE LOOKS FEEBLE. THERE IS GOOD SUBSIDENCE
BEHIND THIS FEATURE BY 18Z TUESDAY BUT ANOTHER WAVE AND THE FRONT
ITSELF WILL EDGE CLOSER TOWARD TUE EVENING...WHICH WILL BRING A
BETTER THREAT OF SHOWERS AND STORMS TO THE MOUNTAINS WITH ISOLATED
TO WIDELY SCATTERED COVERAGE OVER THE FOOTHILLS AND PIEDMONT.
TUESDAY WILL BE HOT...WITH ENOUGH SUN TO SEND TEMPS INTO THE LOWER
TO MID 90S EAST...AND LOWER TO MID 80S WEST.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
AS OF 224 PM EDT MONDAY...
A WEAK COLD FRONT SLIDES ACROSS THE REGION TUESDAY NIGHT...PUSHING
PRECIPITATION TO THE EAST COAST. HIGH PRESSURE BUILDS IN FROM THE
WEST THROUGH WEDNESDAY. THE ASSOCIATED DEW POINT FRONT AND DRIER AIR
IS LAGGING WAY BEHIND AND DOES NOT ENTER THE FORECAST AREA UNTIL
LATE WEDNESDAY MORNING. THIS DEW POINT FRONT MAY MAKE IT AS FAR AS
THE VA/NC BORDER WEDNESDAY AFTERNOON...THEN BEGINS TO RETREAT TO THE
NORTH WEDNESDAY NIGHT AND THURSDAY. SURFACE HIGH PRESSURE WILL KEEP
MOST OF THE AREA DRY BUT COULD SEE ISOLATED DIURNAL SHOWERS SOUTH OF
THE DEW POINT FRONT WEDNESDAY AFTERNOON/EVENING. AS THIS SURFACE
RIDGE DRIFTS OFF THE MID ATLANTIC COAST THURSDAY...SOUTHEAST FLOW
AND ATLANTIC MOISTURE WILL INCREASE THE CHANCE FOR SHOWERS FOR AREAS
ALONG AND EAST OF THE BLUE RIDGE...ESPECIALLY THE NORTH CAROLINA
HIGH COUNTY THURSDAY AFTERNOON. EVEN THOUGH FLOW IS WEAK
ALOFT...WARM SOUTHWEST FLOW WILL OVERRUN THIS RIDGE/INSITU WEDGE TO
PRODUCE A LOW STRATUS DECK AND A CHANCE FOR LIGHT RAIN/DRIZZLE FOR
AREAS EAST OF THE BLUE RIDGE OVERNIGHT THURSDAY.
TEMPERATURES WILL RANGE FROM THE UPPER 70S TO LOWER 80S ACROSS THE
MOUNTAINS AND UPPER 80S TO LOWER 90S EAST WEDNESDAY AFTERNOON.
EASTERLY FLOW THURSDAY WILL PRODUCE UNIFORM TEMPERATURES IN THE 80S.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 248 PM EDT MONDAY...
HIGH PRESSURE EXITS THE MID ATLANTIC COAST ON FRIDAY AND WILL BE
REPLACED BY A LEE TROUGH. WITH AN UPPER LEVEL RIDGE ACROSS THE GULF
STATE TO THE SOUTHEAST COAST...NEARLY ZONAL FLOW MAY BRING A SHORT
WAVE OVER THE REGION FRIDAY. THIS SHORT WAVE WILL HELP SPARK
CONVECTION THROUGH THE AFTERNOON AND EVENING HOURS. IF THIS SHORT
WAVE DOES NOT MATERIALIZE...DIURNAL CONVECTION IS STILL POSSIBLE
WITH ABUNDANT MOISTURE...AFTERNOON HEATING AND A LEE TROUGH. FOR THE
WEEKEND...A COLD FRONT IS EXPECTED TO PASS OVER THE REGION SATURDAY
(GFS) OR SUNDAY (ECM). WITH A STUBBORN UPPER LEVEL RIDGE TO THE
SOUTH...FAVORING THE SLOWER ECM RUN. PREFRONTAL OR DIURNAL
CONVECTION IS POSSIBLE SATURDAY BUT WILL KEEP THE HIGHEST POPS WITH
THE FRONTAL PASSAGE SUNDAY. NOT QUITE SURE IF THE FRONT WILL
COMPLETE CLEAR THE FORECAST AREA AS THE UPPER LEVEL RIDGE CONTINUES
TO HANG ACROSS THE SOUTHERN STATES.
TEMPERATURES WILL REMAIN WARMER THAN NORMAL UNTIL THE FRONT CLEARS
THE AREA. ONCE THE FRONT PASSES...TEMPERATURES WILL RUN COOLER THAN
NORMAL WITH HIGHS IN THE 70S.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
AS OF 640 PM EDT MONDAY...
OVERALL VFR SHOULD PREVAIL OVERNIGHT UNDER DIMINISHING WINDS AND
MOSTLY CLEAR SKIES THIS EVENING. A FEW SHOWERS MAY MAKE A RUN AT
KLWB OVER THE NEXT COUPLE OF HOURS BUT LIKELY TO DISSIPATE
CROSSING THE RIDGES SO LEAVING OUT MENTION WITH JUST A FEW MORE
CLOUDS AROUND. WELL MIXED LOW LEVELS FROM THIS AFTERNOON LIKELY TO
INHIBIT MUCH FOG DEVELOPMENT EXCEPT FOR SOME BRIEF MVFR AT
KLYH/KDAN THAT SHOULD STAY EAST OF ANY UPSTREAM MID DECK THAT MAY
ARRIVE OVER THE WEST TOWARD DAWN. CANT TOTALLY RULE OUT SOME BRIEF
VALLEY FOG AT KLWB/KBCB JUST AFTER MIDNIGHT BEFORE ANY ADDED
CLOUDS PUSH EAST. THUS WENT WITH A BRIEF MVFR TEMPO GROUP AT
KLWB/KBCB FOR FOG ALTHOUGH FORECAST FOG STABILITY VALUES SHOW ONLY
SPOTTY COVERAGE AT BEST.
UPPER TROUGH AND ITS ASSOCIATED COLD FRONT WILL APPROACH FROM THE
NORTHWEST TUESDAY WITH MOSTLY ISOLATED MOUNTAIN SHOWERS/STORMS
EXPECTED DURING THE DAY AHEAD OF THE BOUNDARY. HOWEVER MAY SEE A
MORE ORGANIZED BAND DROP IN FROM THE NW WITH THE LEADING PRE-
FRONTAL CONVERGENCE...SO INCLUDING A VCTS MENTION ACROSS THE
SOUTHEAST WEST VA SITES AROUND MID AFTERNOON AND LATE AT KBCB.
OTRW EXPECTING MOSTLY VFR AFTER EARLY MID DECK ERODES AND
SCATTERED-BROKEN CU FIELDS BETWEEN 4-6K FT TAKE SHAPE WITH
HEATING.
EXTENDED AVIATION DISCUSSION...
FRONT SETTLES CLOSER TUESDAY NIGHT INTO WEDNESDAY...WHEN BETTER
COVERAGE OF SHRA/TSRA IS EXPECTED. HOWEVER LOW CONFIDENCE ON THE
TIMING AND SOUTHWARD POSITION OF THE BOUNDARY ON WEDNESDAY AT THIS
POINT PENDING PRE-FRONTAL COVERAGE FROM TUESDAY NIGHT. FOR NOW APPEARS
MAINLY VFR OUTSIDE OF EARLY MORNING FOG WEDNESDAY...THEN PERIODS
OF MVFR WEDNESDAY AFTERNOON ESPCLY SOUTHERN SECTIONS...AND MAINLY
ACROSS THE SOUTH/SOUTHWEST THURSDAY AFTERNOON FOR MORE
ISOLATED NATURE COVERAGE. FRONT WASHES OUT TO THE SOUTH OF THE
AREA FRIDAY WITH MORE WIDELY SCATTERED DIURNAL NATURE SHOWERS AND
STORMS...THEN PERHAPS BECOMING MORE WIDESPREAD SATURDAY WITH
PERIODIC MVFR IN MORE ORGANIZED COVERAGE AHEAD OF ANOTHER COLD
FRONT ARRIVING FROM THE NORTHWEST LATE. OTRW WILL SEE A DAILY
TREND OF EARLY MVFR/IFR IN FOG...FOLLOWED BY BRIEF VFR...THEN
INCREASING AFTERNOON/EVENING CONVECTION WHEN MVFR TO LOCAL IFR
WILL BE POSSIBLE.
&&
.EQUIPMENT...
AS OF 730 AM EDT FRIDAY ...
THE VISIBILITY SENSOR AT KDAN...DANVILLE REGIONAL AIRPORT...WILL
BE OUT OF SERVICE UNTIL FURTHER NOTICE. A PART HAS BEEN BACK-ORDERED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...JH/WP
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...JH/RAB/WP
EQUIPMENT...RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
744 AM EDT SUN AUG 31 2014
.SYNOPSIS...
THE REGION WILL STAY BETWEEN A LARGE HIGH PRESSURE SYSTEM OVER
THE SOUTHEAST UNITED STATES AND WESTERN ATLANTIC AND A COMPLEX LOW
PRESSURE SYSTEM CROSSING THE GREAT LAKES. A COLD FRONT FINALLY
ARRIVES FROM THE NORTH BY THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EDT SUNDAY...
ELONGATED BAROCLINIC ZONE IS SUPPORTED BY AN UPPER JET AND AXIS OF
VORTICITY THAT EXTENDS FROM THE LOWER MISSISSIPPI VALLEY TO NEW
ENGLAND. UPPER RIDGE REMAINS PARKED OVER THE NORTH CAROLINA COAST.
BAND OF DEEPER MOISTURE SHOWN ON WATER VAPOR AND TOTAL PRECIPITABLE
WATER IMAGES WILL MAKE ONLY SLOW PROGRESS EAST INTO THE COUNTY
WARNING AREA BY MONDAY MORNING.
MODELS BRING CLUSTER OF SHOWERS AND THUNDERSTORMS OVER KENTUCKY AND
TENNESSEE ACROSS MUCH OF THE FORECAST AREA THIS MORNING. NOT SURE
HOW FAR EAST THIS PRECIPITATION WILL GET. 06Z HRRR HAD REASONABLE
TIMING MOVING THE EASTERN EDGE INTO THE FORECAST AREA THROUGH 8AM
SO WILL BE FOLLOWING THAT ALONG WITH RADAR TRENDS.
LARGER BAND OF SHOWERS WILL PIVOT ENOUGH TO REACH SOUTHEAST WEST
VIRGINIA TONIGHT...SIMILAR TO ORIENTATION OF WPC QPF FORECAST AND
THE 00Z GFS...SLIGHTLY FARTHER SOUTH THAN THE 00Z NAM.
4KM NAM AND HRRR DEVELOP THUNDERSTORMS ALONG THE BLUE RIDGE THIS
AFTERNOON...CLOSE TO THE EDGE OF THE THICKER CLOUD COVER. EXPECT
THE COVERAGE OF THUNDERSTORMS IN THE EAST TO DIMINISH AFTER SUNSET.
CLOUDS WILL LIMIT HEATING AND INSTABILITY TODAY. STAYED CLOSER TO
BIAS CORRECTED MAV GUIDANCE FOR MAXIMUM TEMPERATURES. HUMID AIR MASS
AND VERY MILD DEW POINTS WILL RESULT IN LITTLE COOLING TONIGHT. USED
WARMER MET GUIDANCE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM EDT SUNDAY...
PROGRESSIVE NORTHERN STREAM FLOW WILL PRODUCE TROUGHING ACROSS THE
NORTHEAST BY MONDAY MORNING. SEVERAL SHORTWAVES TRAVERSE ACROSS THE
MID ATLANTIC REGION. THESE UPPER DISTURBANCES WILL SHAPE THE TIMING
OF CONVECTION.
AN UPPER DISTURBANCE WILL SHIFT ACROSS THE GREAT LAKES FROM THE OHIO
RIVER VALLEY MONDAY MORNING...ENHANCING THE CHANCES OF SHOWERS IN
THE WEST-NORTHWEST. THE SUBTROPICAL BERMUDA HIGH PRESSURE WILL
REMAIN IN PLACE. A VERY MOIST SOUTHWEST FLOW WILL CONTINUE LABOR
DAY. HIGH TEMPERATURES MONDAY WILL RANGE FROM THE UPPER 70S IN THE
MOUNTAINS TO THE LOWER 90S IN THE PIEDMONT.
SCATTERED SHOWERS AND THUNDERSTORMS REDEVELOP MONDAY AFTERNOON WITH
SOLAR HEATING. SOME OF THE THUNDERSTORMS MAY CONTAIN LOCALLY HEAVY
RAINS. RAINFALL WILL DIMINISH QUICKLY AS THE SUN SETS AND SHOULD SEE
DRY...ALBEIT WARM AND MUGGY...CONDITIONS PERSIST THROUGH MONDAY
NIGHT. LOW TEMPERATURES MONDAY NIGHT WILL VARY FROM THE LOWER 60S IN
THE WEST TO THE AROUND 70 IN THE EAST.
DEEP LAYER MOISTURE INCREASES TUESDAY AS ANOTHER LOW PRESSURE SYSTEM
MOVING ACROSS EASTERN CANADA WILL DRAG A COLD FRONT SOUTH OF THE
GREAT LAKES. BETTER CHANCES FOR CONVECTION WILL BE FOUND ACROSS THE
HIGHER TERRAIN...WHERE STRONGER UPPER LEVEL SUPPORT WILL BE LOCATED.
HIGHS TUESDAY WILL CLIMB INTO THE LOWER 80S IN THE MOUNTAINS TO THE
LOWER 90S IN THE PIEDMONT.
MODEL TREND HAVE BEEN SLOWING THE TIMING OF THE FRONT AND EXPECT THE
COLD FRONT WILL STALL FURTHER NORTH TUESDAY NIGHT DUE TO THE UPPER
LEVEL RIDGING IN PLACE ACROSS THE SOUTHEAST STATES. LOWS WILL FALL
INTO THE MID 60S TO THE LOW 70S TUESDAY NIGHT.
KEPT THE HIGHEST POPS ACROSS THE SOUTH WEDNESDAY ALONG THE STALLED
FRONTAL BOUNDARY. WHILE...HIGH PRESSURE PASSING ACROSS THE GREAT
LAKES SHOULD KEEP THE NORTHERN HALF OF OUR AREA DRY. HIGHS WEDNESDAY
WILL BE FROM THE LOWER 80S IN THE WEST TO AROUND 90 DEGREES IN THE
EAST. SLOWLY DRY THINGS OUT WEDNESDAY NIGHT FROM NORTH TO SOUTH. LOW
TEMPERATURES WILL DROP INTO THE UPPER 50S IN THE NORTHWEST MOUNTAINS
TO NEAR 70 DEGREES IN THE PIEDMONT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 330 PM SATURDAY...
UPPER LEVEL RIDGING WILL SHIFT NORTHWARD FROM THE SOUTHEAST STATES
OVER THE MID ATLANTIC DURING THE SECOND HALF OF THE WEEK...RESULTING
IN BOTH WARMER TEMPERATURES AND WEAKER WINDS ALOFT. THIS WILL MAKE
FOR MORE STABLE CONDITIONS THAT WILL KEEP SHOWER AND THUNDERSTORM
ACTIVITY DISORGANIZED THROUGH THE PERIOD. ANY RAINFALL WHICH
DEVELOPS WILL BE DRIVEN MAINLY BY DAYTIME HEATING...WHICH WILL ALLOW
THIS ACTIVITY TO FIZZLE AFTER SUNSET.
HIGH PRESSURE WILL PASS OFF THE NEW ENGLAND COAST ON THURSDAY...
RESULTING IN A WEAK WEDGING PATTERN WITH EASTERLY FLOW OFF THE
ATLANTIC. THIS WILL LIKELY BE THE DRIEST DAY OF THE PERIOD.
WINDS WILL SHIFT SOUTHWESTERLY AGAIN ON FRIDAY AS ANOTHER COLD FRONT
SINKS SOUTH FROM THE GREAT LAKES. STRONGER FLOW OFF THE ATLANTIC
WILL RESULT IN INCREASED MOISTURE...AND WILL EXPECT SPOTTY SHOWER
AND THUNDERSTORM ACTIVITY DURING THE AFTERNOON AND EVENING.
EXPECT TEMPERATURES TO REMAIN SLIGHTLY ABOVE NORMAL FOR THE PERIOD.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 735 AM EDT SUNDAY...
SATELLITE PICTURES SHOWED AN AREA OF IFR CLOUDS SPREADING NORTH
OUT OF NORTH CAROLINA. THESE CLOUDS MAY BRIEFLY REACH KLYH OR KDAN
BEFORE 10AM.
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WERE MOVING NORTH-
NORTHEAST ACROSS THE CENTRAL APPALACHIANS THIS MORNING. EXPECT
RAIN AT KROA/KBCB AND KLWB THROUGH 14Z/10AM THIS MORNING. CEILINGS
AND VISIBILITIES WILL REMAIN VFR IN ALL BUT THE HEAVIEST SHOWERS.
THE PRECIPITATION WILL GRADUALLY DIMINISH THIS MORNING AS IT MOVES
EAST. THERE WILL BE A BREAK IN THE PRECIPITATION THROUGH ABOUT
1PM/17Z...THEN MORE SHOWERS AND THUNDERSTORMS WILL DEVELOP. HRRR
GUIDANCE SHOWED THE MOST LIKELY LOCATION FOR REDEVELOPMENT WILL BE
ALONG THE BLUE RIDGE. BUT THIS WILL DEPEND ON HOW MUCH HEATING AND
RESULTING INSTABILITY HAS OCCURRED. MEDIUM CONFIDENCE ON THE
LOCATION OF STORMS THIS AFTERNOON AND EVENING.
ONCE THE PRECIPITATION MOVES OUT OF THE AREA LATE TONIGHT...HIGH
AMOUNTS OF LOW LEVEL MOISTURE...ALONG WITH SOME BREAKS IN THE
CLOUD COVER WILL RESULT IN FOG FORMATION. HIGH CONFIDENCE OF MVFR
FOG ACROSS THE REGION LATE TONIGHT.
EXTENDED DISCUSSION...
IMPULSES EXIT BY MONDAY LEAVING THE REGION IN BETWEEN THIS
EXITING SYSTEM AND THE NEXT UPSTREAM COLD FRONT. THIS SHOULD ALLOW
FOR MORE IN THE WAY OF WIDESPREAD VFR ON MONDAY AFTER EARLY FOG
FADES...WITH ONLY ISOLATED CONVECTION LIKELY DURING THE AFTERNOON
INCLUDING SPOTTY MVFR CONDITIONS.
ANOTHER COLD FRONT IS EXPECTED TO PRODUCE SIMILAR CONDITIONS AS IT
APPROACHES FROM THE NW TUESDAY...THEN BETTER COVERAGE OF
SHRA/TSRA WEDNESDAY WITH THE FRONT PASSING...AND ACROSS THE SOUTH
THURSDAY WHERE THE BOUNDARY STALLS. HOWEVER LOW CONFIDENCE ON THE TIMING
AND SOUTHWARD POSITION OF THE BOUNDARY AT THIS POINT. THUS
APPEARS MAINLY VFR FOR NOW TUE-THU OUTSIDE OF AFTERNOON/EVENING
CONVECTION AND TYPICAL EARLY MORNING FOG IN THE VALLEYS AND WHERE
EARLIER HEAVY RAIN OCCURRED.
&&
.EQUIPMENT...
AS OF 730 AM EDT FRIDAY ...
THE VISIBILITY SENSOR AT KDAN...DANVILLE REGIONAL AIRPORT...WILL
BE OUT OF SERVICE UNTIL FURTHER NOTICE. A PART HAS BEEN BACK-ORDERED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...NF
AVIATION...AMS
EQUIPMENT...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
405 AM EDT SUN AUG 31 2014
.SYNOPSIS...
THE REGION WILL STAY BETWEEN A LARGE HIGH PRESSURE SYSTEM OVER
THE SOUTHEAST UNITED STATES AND WESTERN ATLANTIC AND A COMPLEX LOW
PRESSURE SYSTEM CROSSING THE GREAT LAKES. A COLD FRONT FINALLY
ARRIVES FROM THE NORTH BY THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EDT SUNDAY...
ELONGATED BAROCLINIC ZONE IS SUPPORTED BY AN UPPER JET AND AXIS OF
VORTICITY THAT EXTENDS FROM THE LOWER MISSISSIPPI VALLEY TO NEW
ENGLAND. UPPER RIDGE REMAINS PARKED OVER THE NORTH CAROLINA COAST.
BAND OF DEEPER MOISTURE SHOWN ON WATER VAPOR AND TOTAL PRECIPITABLE
WATER IMAGES WILL MAKE ONLY SLOW PROGRESS EAST INTO THE COUNTY
WARNING AREA BY MONDAY MORNING.
MODELS BRING CLUSTER OF SHOWERS AND THUNDERSTORMS OVER KENTUCKY AND
TENNESSEE ACROSS MUCH OF THE FORECAST AREA THIS MORNING. NOT SURE
HOW FAR EAST THIS PRECIPITATION WILL GET. 06Z HRRR HAD REASONABLE
TIMING MOVING THE EASTERN EDGE INTO THE FORECAST AREA THROUGH 8AM
SO WILL BE FOLLOWING THAT ALONG WITH RADAR TRENDS.
LARGER BAND OF SHOWERS WILL PIVOT ENOUGH TO REACH SOUTHEAST WEST
VIRGINIA TONIGHT...SIMILAR TO ORIENTATION OF WPC QPF FORECAST AND
THE 00Z GFS...SLIGHTLY FARTHER SOUTH THAN THE 00Z NAM.
4KM NAM AND HRRR DEVELOP THUNDERSTORMS ALONG THE BLUE RIDGE THIS
AFTERNOON...CLOSE TO THE EDGE OF THE THICKER CLOUD COVER. EXPECT
THE COVERAGE OF THUNDERSTORMS IN THE EAST TO DIMINISH AFTER SUNSET.
CLOUDS WILL LIMIT HEATING AND INSTABILITY TODAY. STAYED CLOSER TO
BIAS CORRECTED MAV GUIDANCE FOR MAXIMUM TEMPERATURES. HUMID AIR MASS
AND VERY MILD DEW POINTS WILL RESULT IN LITTLE COOLING TONIGHT. USED
WARMER MET GUIDANCE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM EDT SUNDAY...
PROGRESSIVE NORTHERN STREAM FLOW WILL PRODUCE TROUGHING ACROSS THE
NORTHEAST BY MONDAY MORNING. SEVERAL SHORTWAVES TRAVERSE ACROSS THE
MID ATLANTIC REGION. THESE UPPER DISTURBANCES WILL SHAPE THE TIMING
OF CONVECTION.
AN UPPER DISTURBANCE WILL SHIFT ACROSS THE GREAT LAKES FROM THE OHIO
RIVER VALLEY MONDAY MORNING...ENHANCING THE CHANCES OF SHOWERS IN
THE WEST-NORTHWEST. THE SUBTROPICAL BERMUDA HIGH PRESSURE WILL
REMAIN IN PLACE. A VERY MOIST SOUTHWEST FLOW WILL CONTINUE LABOR
DAY. HIGH TEMPERATURES MONDAY WILL RANGE FROM THE UPPER 70S IN THE
MOUNTAINS TO THE LOWER 90S IN THE PIEDMONT.
SCATTERED SHOWERS AND THUNDERSTORMS REDEVELOP MONDAY AFTERNOON WITH
SOLAR HEATING. SOME OF THE THUNDERSTORMS MAY CONTAIN LOCALLY HEAVY
RAINS. RAINFALL WILL DIMINISH QUICKLY AS THE SUN SETS AND SHOULD SEE
DRY...ALBEIT WARM AND MUGGY...CONDITIONS PERSIST THROUGH MONDAY
NIGHT. LOW TEMPERATURES MONDAY NIGHT WILL VARY FROM THE LOWER 60S IN
THE WEST TO THE AROUND 70 IN THE EAST.
DEEP LAYER MOISTURE INCREASES TUESDAY AS ANOTHER LOW PRESSURE SYSTEM
MOVING ACROSS EASTERN CANADA WILL DRAG A COLD FRONT SOUTH OF THE
GREAT LAKES. BETTER CHANCES FOR CONVECTION WILL BE FOUND ACROSS THE
HIGHER TERRAIN...WHERE STRONGER UPPER LEVEL SUPPORT WILL BE LOCATED.
HIGHS TUESDAY WILL CLIMB INTO THE LOWER 80S IN THE MOUNTAINS TO THE
LOWER 90S IN THE PIEDMONT.
MODEL TREND HAVE BEEN SLOWING THE TIMING OF THE FRONT AND EXPECT THE
COLD FRONT WILL STALL FURTHER NORTH TUESDAY NIGHT DUE TO THE UPPER
LEVEL RIDGING IN PLACE ACROSS THE SOUTHEAST STATES. LOWS WILL FALL
INTO THE MID 60S TO THE LOW 70S TUESDAY NIGHT.
KEPT THE HIGHEST POPS ACROSS THE SOUTH WEDNESDAY ALONG THE STALLED
FRONTAL BOUNDARY. WHILE...HIGH PRESSURE PASSING ACROSS THE GREAT
LAKES SHOULD KEEP THE NORTHERN HALF OF OUR AREA DRY. HIGHS WEDNESDAY
WILL BE FROM THE LOWER 80S IN THE WEST TO AROUND 90 DEGREES IN THE
EAST. SLOWLY DRY THINGS OUT WEDNESDAY NIGHT FROM NORTH TO SOUTH. LOW
TEMPERATURES WILL DROP INTO THE UPPER 50S IN THE NORTHWEST MOUNTAINS
TO NEAR 70 DEGREES IN THE PIEDMONT.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 330 PM SATURDAY...
UPPER LEVEL RIDGING WILL SHIFT NORTHWARD FROM THE SOUTHEAST STATES
OVER THE MID ATLANTIC DURING THE SECOND HALF OF THE WEEK...RESULTING
IN BOTH WARMER TEMPERATURES AND WEAKER WINDS ALOFT. THIS WILL MAKE
FOR MORE STABLE CONDITIONS THAT WILL KEEP SHOWER AND THUNDERSTORM
ACTIVITY DISORGANIZED THROUGH THE PERIOD. ANY RAINFALL WHICH
DEVELOPS WILL BE DRIVEN MAINLY BY DAYTIME HEATING...WHICH WILL ALLOW
THIS ACTIVITY TO FIZZLE AFTER SUNSET.
HIGH PRESSURE WILL PASS OFF THE NEW ENGLAND COAST ON THURSDAY...
RESULTING IN A WEAK WEDGING PATTERN WITH EASTERLY FLOW OFF THE
ATLANTIC. THIS WILL LIKELY BE THE DRIEST DAY OF THE PERIOD.
WINDS WILL SHIFT SOUTHWESTERLY AGAIN ON FRIDAY AS ANOTHER COLD FRONT
SINKS SOUTH FROM THE GREAT LAKES. STRONGER FLOW OFF THE ATLANTIC
WILL RESULT IN INCREASED MOISTURE...AND WILL EXPECT SPOTTY SHOWER
AND THUNDERSTORM ACTIVITY DURING THE AFTERNOON AND EVENING.
EXPECT TEMPERATURES TO REMAIN SLIGHTLY ABOVE NORMAL FOR THE PERIOD.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
AS OF 125 AM EDT SUNDAY...
SATELLITE PICTURES SHOWED AN EXPANSIVE BAND OF DEEP MOISTURE FROM
THE GULF OF MEXICO INTO THE GREAT LAKES. AXIS OF VORTICITY ALONG
THIS SAME CORRIDOR WILL GENERATE SHOWERS AND THUNDERSTORMS TODAY
AND TONIGHT. ONGOING SHOWERS AND THUNDERSTORMS OVER THE TENNESSEE
AND OHIO VALLEYS EARLY THIS MORNING WILL GRADUALLY MOVE EAST IN TO
WEST VIRGINIA AND VIRGINIA TODAY. LOWER CONFIDENCE AS TO HOW FAR
EAST THIS PRECIPITATION WILL GET BY 00Z/8PM. FOR NOW HAVE LEFT
PRECIPITATION OUT OF THE KBCB AND KROA TAFS. ALSO KEPT KLYH AND
KDAN DRY. HIGHER CONFIDENCE THAT KLWB AND KBLF WILL HAVE A
PROLONGED PERIOD OF SHOWERS OVERNIGHT.
MODELS BRING IFR CEILINGS INTO KLYH AND KDAN EARLY THIS MORNING.
EXPECT ANY STRATUS THAT DOES DEVELOP WILL LIFT TO VFR SHORTLY
AFTER SUNRISE.
EXTENDED DISCUSSION...
IMPULSES EXIT BY MONDAY LEAVING THE REGION IN BETWEEN THIS
EXITING SYSTEM AND THE NEXT UPSTREAM COLD FRONT. THIS SHOULD ALLOW
FOR MORE IN THE WAY OF WIDESPREAD VFR ON MONDAY AFTER EARLY FOG
FADES WITH ONLY ISOLATED CONVECTION LIKELY DURING THE AFTERNOON
INCLUDING SPOTTY MVFR.
ANOTHER COLD FRONT IS EXPECTED TO PRODUCE SIMILAR CONDITIONS AS IT
APPROACHES FROM THE NW TUESDAY...THEN PERHAPS BETTER COVERAGE OF
SHRA/TSRA WEDNESDAY WITH THE FRONT PASSING...AND ACROSS THE SOUTH
THURSDAY WHERE THE BOUNDARY LOOKS TO STALL. HOWEVER TIMING AND
SOUTHWARD EXTENT OF THE BOUNDARY QUITE LOW CONFIDENCE AT THIS
POINT. THUS APPEARS MAINLY VFR FOR NOW TUE-THU OUTSIDE OF
AFTERNOON/EVENING CONVECTION AND TYPICAL EARLY MORNING FOG IN THE
VALLEYS AND WHERE EARLIER HEAVY RAIN OCCURRED.
&&
.EQUIPMENT...
AS OF 730 AM EDT FRIDAY ...
THE VISIBILITY SENSOR AT KDAN...DANVILLE REGIONAL AIRPORT...WILL
BE OUT OF SERVICE UNTIL FURTHER NOTICE. A PART HAS BEEN BACK-ORDERED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...NF
AVIATION...AMS
EQUIPMENT...AMS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1050 PM CDT MON SEP 1 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 233 PM CDT MON SEP 1 2014
WARM AND RATHER HUMID WITH SHOWERS AND THUNDERSTORMS AT TIMES
THROUGH MOST OF THE HOLIDAY-SHORTENED WORK WEEK.
STG SUBTROPICAL RIDGE ACRS THE SRN CONUS WL EXPAND NWD A BIT THE
NEXT FEW DAYS AS SEASONABLY STG AND PROGRESSIVE BAND OF WESTERLIES
TO IT/S N GRADUALLY RECEDES FARTHER NWD. THE PRIMARY FRONTAL ZONE
SEPARATING WARM AND VERY MOIST TROPICAL AIR TO THE S FM COOLER AND
DRIER CANADIAN AIR TO THE N WL REMAIN STETCHED OUT W-E ALONG THE
SRN EDGE OF THE MAIN WESTERLIES...AND CLOSE TO THE FCST AREA.
THIS WL RESULT IN SEVERAL OPPORTUNITIES FOR PCPN...LIKELY RESULTING
IN ABV NORMAL AMNTS. TEMPS AND HUMIDITIES ARE EXPECTED TO REMAIN
AOA NORMAL FOR THE NEXT SEVERAL DAYS...THEN DROP BACK CLOSE TO
NORMAL BY THE WEEKEND.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 233 PM CDT MON SEP 1 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A COLD
FRONT SLICING ACROSS NORTH-CENTRAL TO SOUTHWEST WISCONSIN EARLY THIS
AFTERNOON. PRIMARY AREA OF RAIN AHEAD OF A SHORTWAVE HAS EXITED
NORTHEAST WISCONSIN...BUT ARE SEEING SCATTERED SHOWER AND ISOLATED
THUNDERSTORM DEVELOPMENT ALONG THE COLD FRONT WHERE ML CAPE VALUES
ARE AROUND 400 J/KG. THIS FRONT WILL CONTINUE TO MARCH EAST THIS
AFTERNOON AND REACH EAST-CENTRAL WISCONSIN BY AROUND 00Z. WILL HAVE
TO KEEP A SCT SHOWER/ISOLD TSTORM MENTION AHEAD OF THE FRONT UNTIL
THEN. CLEARING SKIES EXIST BEHIND THE FRONT OVER FAR WESTERN
WISCONSIN AND MINNESOTA. THEN THE NEXT SHORTWAVE IS QUICKLY MOVING
EAST OVER WESTERN SOUTH DAKOTA WHERE A FEW LIGHTNING STRIKES ARE
OCCURRING. TIMING THE END OF PRECIP TONIGHT AND POTENTIAL FOR
THUNDERSTORMS TOMORROW ARE THE MAIN FORECAST CONCERNS.
TONIGHT...THE COLD FRONT WILL BE SLIDING SOUTHEAST ACROSS
EAST-CENTRAL AND SOUTHERN WISCONSIN EARLY IN THE EVENING...AND WILL
LEAVE A SLIGHT CHANCE OF SHOWERS OVER CALUMET...KEWAUNEE...AND
MANITOWOC COUNTIES FOR THE 00-01Z PERIOD. THEN SHOULD SEE A CLEARING
PERIOD THROUGH THE REST OF THE EVENING AS DRIER MID-LEVEL AIR WORKS
IN FROM THE WEST. A MODESTLY TIGHT PRESSURE GRADIENT WILL BE IN
PLACE FOR THE EVENING...BUT SHOULD LOOSEN OVERNIGHT...AND PROBABLY
ENOUGH FOR FOG FORMATION OVER N-C WISCONSIN. NOT AS CONFIDENT ABOUT
THE REST OF THE AREA AS STATISTICAL GUIDANCE IS RATHER PESSIMISTIC
ABOUT THE THREAT OF FOG. WILL KEEP A PATCHY MENTION ALONG THE WIS
RIVER VALLEY TOO. THE NEXT SHORTWAVE WILL BE MOVING INTO THE
NORTHERN MISSISSIPPI VALLEY LATE AND SHOULD HAVE INCREASING CLOUDS
TOWARDS SUNRISE. LOWS RANGING FROM THE LOW 50S NORTH TO NEAR 60S SOUTH.
TUESDAY...THE SHORTWAVE TROUGH WILL MOVE ACROSS WISCONSIN DURING THE
MORNING BEFORE EXITING BY MID TO LATE AFTERNOON. THERE MAY BE A
SPOTTY SHOWER WITH THE WAVE EARLY IN THE MORNING...BUT WITH DAYTIME
HEATING...MODELS PROJECT STEEP LOW LEVEL LAPSE RATES DEVELOPING ALL
THE WAY UP TO 750MB. CONVECTIVE TEMPERATURES ARE ONLY PROJECTED TO
REACH THE LOWER TO THE MIDDLE 70S...WHICH ARE SLIGHTLY BELOW THE
FORECASTED MAX TEMPS FOR THE DAY. IN ADDITION...ML CAPES ARE
PROJECTED TO RANGE FROM 500-1000 J/KG BY MIDDAY TO EARLY AFTERNOON
WITH NO CAP IN PLACE. AS A RESULT...SHOULD SEE ISOLATED SHOWERS
EARLY BECOME MORE SCATTERED BY MIDDAY AS CONVECTIVE TEMPS ARE
APPROACHED. WITH THOSE CAPES...CANNOT RULE OUT THUNDERSTORMS...AND
WILL KEEP A MENTION IN THE FORECAST. LOW FREEZING LEVELS AROUND
10KFT AND 0-6KM BULK SHEARS OF 30-35 KTS SUGGEST GUSTY WINDS AND
SMALL HAIL WILL BE POSSIBLE WITHIN ANY THUNDERSTORMS. HIGHS RANGING
FROM THE LOWER 70S NORTH TO UPPER 70S SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 233 PM CDT MON SEP 1 2014
ISOLD-SCT SHRA WL PROBABLY BE GONE BY TOMORROW NGT...SO WL START
THE LONG-TERM FCST OUT DRY. WK SFC PRESSURE GRADIENT AND 10-15 KT
WLY FLOW AT 850 MB WL NOT BE IDEAL FOR FOG TOMORROW NGT. BUT
GIVEN RECENT RAINS...WL MENTION PATCHY FOG ACRS THE AREA AFTER
MIDNIGHT.
QUIET WX SHOULD AT LEAST LINGER INTO WED...AND QUITE LIKELY LAST
THE WHOLE DAY. WL JUST BRUSH SOME LOW CHC POPS ACRS THE NW PART
OF THE AREA IN THE AFTN IN CASE SOME CONVECTION FM THE W CAN MAKE
IT THAT FAR E IN THE RELATIVELY FAST/FLAT WLY FLOW ALOFT.
A 24-36 HR PERIOD OF VERY ACTIVE WX WL PROBABLY FOLLOW FOR THE
LATTER HALF OF THE ABBREVIATED WORK WEEK. STG SHRTWV IN THE MAIN
BAND OF WESTERLIES WL BE PROGRESSING EWD ALONG THE U.S./CANADIAN
BORDER WED NGT...LIKELY RESULTING IN CYCLONGENESIS ACRS THE NRN
PLAINS. STRENGTHENING LLJ WL LIKELY VEER INTO THE FCST AREA
DURING THE NGT...PROBABLY BRINGING AN MCS FROM THE NRN PLAINS EWD
INTO THE FCST AREA. THE MAIN RESERVOIR OF VERY MOIST AND UNSTABLE
AIR WL BE TO THE SW...SO THE SVR THREAT WL MOST LIKELY REMAIN TO
OUR W. BUT WL NEED TO CLOSELY MONITOR THE SITN OVER THE NEXT FEW
DAYS AS THE FCST AREA WL BE ON THE ERN EDGE OF ELEVATED MIXED
LAYER...WITH FAIRLY STEEP MIDDLE LEVEL LAPSE RATES EDGING IN FM
THE W.
AS WAS THE CASE THIS MORNING AND BACK LAST MONDAY /AUG 25/...
CONVECTIVE POTENTIAL THU WL DEPEND ON THE BEHAVIOR OF THE
DEPARTING NOCTURNAL CONVECTION. WHAT MAY BE DIFFERENT THIS TIME
IS HIGHER UPR HEIGHTS AND STRONG WLY FLOW ALOFT DRIVING ELEVATED
MIXED LAYER ACRS THE AREA...RESULTING IN VERY WARM TEMPS ALOFT AND
POSSIBLY RESULTING IN STG CAPPING. ASSUMING CONVECTION SHUTS
DOWN...TEMPS WL LIKELY SOAR WELL INTO THE 80S WITH DWPTS RISING
INTO THE LOWER TO MIDDLE 70S. IF THAT OCCURS...A VERY VOLATILE ATM
COULD BE IN PLACE AS THE COLD FRONT STARTS IT/S PUSH ACRS THE AREA
THU AFTN/EVENING.
TOO MANY IF/S TO GET TOO SPECIFIC WITH THE FCST THIS FAR OUT...
BUT GIVEN THE OVERALL LOOK OF THE LARGE SCALE SET-UP...WL BEGIN TO
OPEN THE DOOR TO SOME SVR POTENTIAL IN THE HWO.
COOLER AND DRIER AIR WL PUSH INTO THE AREA IN THE WAKE OF THE
FRONT...AND LIKELY LINGER INTO EARLY NEXT WEEK.
NO SIG CHGS NEED TO BROAD-BASED EXTENDED FCST INITIALIZATION
GRIDS.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1047 PM CDT MON SEP 1 2014
CLEARING SKIES THIS EVENING AND DIMINISHING SURFACE WINDS WILL LIKELY
LEAD TO GROUND FOG FORMATION LATE TONIGHT...THOUGH STRONGER FLOW
JUST OFF THE SURFACE SHOULD LIMIT EXTENT. WEAK DISTURBANCES MOVING
THROUGH THE FLOW WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS
BY TUESDAY MORNING. &&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......TE
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
700 PM CDT MON SEP 1 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 233 PM CDT MON SEP 1 2014
WARM AND RATHER HUMID WITH SHOWERS AND THUNDERSTORMS AT TIMES
THROUGH MOST OF THE HOLIDAY-SHORTENED WORK WEEK.
STG SUBTROPICAL RIDGE ACRS THE SRN CONUS WL EXPAND NWD A BIT THE
NEXT FEW DAYS AS SEASONABLY STG AND PROGRESSIVE BAND OF WESTERLIES
TO IT/S N GRADUALLY RECEDES FARTHER NWD. THE PRIMARY FRONTAL ZONE
SEPARATING WARM AND VERY MOIST TROPICAL AIR TO THE S FM COOLER AND
DRIER CANADIAN AIR TO THE N WL REMAIN STETCHED OUT W-E ALONG THE
SRN EDGE OF THE MAIN WESTERLIES...AND CLOSE TO THE FCST AREA.
THIS WL RESULT IN SEVERAL OPPORTUNITIES FOR PCPN...LIKELY RESULTING
IN ABV NORMAL AMNTS. TEMPS AND HUMIDITIES ARE EXPECTED TO REMAIN
AOA NORMAL FOR THE NEXT SEVERAL DAYS...THEN DROP BACK CLOSE TO
NORMAL BY THE WEEKEND.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 233 PM CDT MON SEP 1 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A COLD
FRONT SLICING ACROSS NORTH-CENTRAL TO SOUTHWEST WISCONSIN EARLY THIS
AFTERNOON. PRIMARY AREA OF RAIN AHEAD OF A SHORTWAVE HAS EXITED
NORTHEAST WISCONSIN...BUT ARE SEEING SCATTERED SHOWER AND ISOLATED
THUNDERSTORM DEVELOPMENT ALONG THE COLD FRONT WHERE ML CAPE VALUES
ARE AROUND 400 J/KG. THIS FRONT WILL CONTINUE TO MARCH EAST THIS
AFTERNOON AND REACH EAST-CENTRAL WISCONSIN BY AROUND 00Z. WILL HAVE
TO KEEP A SCT SHOWER/ISOLD TSTORM MENTION AHEAD OF THE FRONT UNTIL
THEN. CLEARING SKIES EXIST BEHIND THE FRONT OVER FAR WESTERN
WISCONSIN AND MINNESOTA. THEN THE NEXT SHORTWAVE IS QUICKLY MOVING
EAST OVER WESTERN SOUTH DAKOTA WHERE A FEW LIGHTNING STRIKES ARE
OCCURRING. TIMING THE END OF PRECIP TONIGHT AND POTENTIAL FOR
THUNDERSTORMS TOMORROW ARE THE MAIN FORECAST CONCERNS.
TONIGHT...THE COLD FRONT WILL BE SLIDING SOUTHEAST ACROSS
EAST-CENTRAL AND SOUTHERN WISCONSIN EARLY IN THE EVENING...AND WILL
LEAVE A SLIGHT CHANCE OF SHOWERS OVER CALUMET...KEWAUNEE...AND
MANITOWOC COUNTIES FOR THE 00-01Z PERIOD. THEN SHOULD SEE A CLEARING
PERIOD THROUGH THE REST OF THE EVENING AS DRIER MID-LEVEL AIR WORKS
IN FROM THE WEST. A MODESTLY TIGHT PRESSURE GRADIENT WILL BE IN
PLACE FOR THE EVENING...BUT SHOULD LOOSEN OVERNIGHT...AND PROBABLY
ENOUGH FOR FOG FORMATION OVER N-C WISCONSIN. NOT AS CONFIDENT ABOUT
THE REST OF THE AREA AS STATISTICAL GUIDANCE IS RATHER PESSIMISTIC
ABOUT THE THREAT OF FOG. WILL KEEP A PATCHY MENTION ALONG THE WIS
RIVER VALLEY TOO. THE NEXT SHORTWAVE WILL BE MOVING INTO THE
NORTHERN MISSISSIPPI VALLEY LATE AND SHOULD HAVE INCREASING CLOUDS
TOWARDS SUNRISE. LOWS RANGING FROM THE LOW 50S NORTH TO NEAR 60S SOUTH.
TUESDAY...THE SHORTWAVE TROUGH WILL MOVE ACROSS WISCONSIN DURING THE
MORNING BEFORE EXITING BY MID TO LATE AFTERNOON. THERE MAY BE A
SPOTTY SHOWER WITH THE WAVE EARLY IN THE MORNING...BUT WITH DAYTIME
HEATING...MODELS PROJECT STEEP LOW LEVEL LAPSE RATES DEVELOPING ALL
THE WAY UP TO 750MB. CONVECTIVE TEMPERATURES ARE ONLY PROJECTED TO
REACH THE LOWER TO THE MIDDLE 70S...WHICH ARE SLIGHTLY BELOW THE
FORECASTED MAX TEMPS FOR THE DAY. IN ADDITION...ML CAPES ARE
PROJECTED TO RANGE FROM 500-1000 J/KG BY MIDDAY TO EARLY AFTERNOON
WITH NO CAP IN PLACE. AS A RESULT...SHOULD SEE ISOLATED SHOWERS
EARLY BECOME MORE SCATTERED BY MIDDAY AS CONVECTIVE TEMPS ARE
APPROACHED. WITH THOSE CAPES...CANNOT RULE OUT THUNDERSTORMS...AND
WILL KEEP A MENTION IN THE FORECAST. LOW FREEZING LEVELS AROUND
10KFT AND 0-6KM BULK SHEARS OF 30-35 KTS SUGGEST GUSTY WINDS AND
SMALL HAIL WILL BE POSSIBLE WITHIN ANY THUNDERSTORMS. HIGHS RANGING
FROM THE LOWER 70S NORTH TO UPPER 70S SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 233 PM CDT MON SEP 1 2014
ISOLD-SCT SHRA WL PROBABLY BE GONE BY TOMORROW NGT...SO WL START
THE LONG-TERM FCST OUT DRY. WK SFC PRESSURE GRADIENT AND 10-15 KT
WLY FLOW AT 850 MB WL NOT BE IDEAL FOR FOG TOMORROW NGT. BUT
GIVEN RECENT RAINS...WL MENTION PATCHY FOG ACRS THE AREA AFTER
MIDNIGHT.
QUIET WX SHOULD AT LEAST LINGER INTO WED...AND QUITE LIKELY LAST
THE WHOLE DAY. WL JUST BRUSH SOME LOW CHC POPS ACRS THE NW PART
OF THE AREA IN THE AFTN IN CASE SOME CONVECTION FM THE W CAN MAKE
IT THAT FAR E IN THE RELATIVELY FAST/FLAT WLY FLOW ALOFT.
A 24-36 HR PERIOD OF VERY ACTIVE WX WL PROBABLY FOLLOW FOR THE
LATTER HALF OF THE ABBREVIATED WORK WEEK. STG SHRTWV IN THE MAIN
BAND OF WESTERLIES WL BE PROGRESSING EWD ALONG THE U.S./CANADIAN
BORDER WED NGT...LIKELY RESULTING IN CYCLONGENESIS ACRS THE NRN
PLAINS. STRENGTHENING LLJ WL LIKELY VEER INTO THE FCST AREA
DURING THE NGT...PROBABLY BRINGING AN MCS FROM THE NRN PLAINS EWD
INTO THE FCST AREA. THE MAIN RESERVOIR OF VERY MOIST AND UNSTABLE
AIR WL BE TO THE SW...SO THE SVR THREAT WL MOST LIKELY REMAIN TO
OUR W. BUT WL NEED TO CLOSELY MONITOR THE SITN OVER THE NEXT FEW
DAYS AS THE FCST AREA WL BE ON THE ERN EDGE OF ELEVATED MIXED
LAYER...WITH FAIRLY STEEP MIDDLE LEVEL LAPSE RATES EDGING IN FM
THE W.
AS WAS THE CASE THIS MORNING AND BACK LAST MONDAY /AUG 25/...
CONVECTIVE POTENTIAL THU WL DEPEND ON THE BEHAVIOR OF THE
DEPARTING NOCTURNAL CONVECTION. WHAT MAY BE DIFFERENT THIS TIME
IS HIGHER UPR HEIGHTS AND STRONG WLY FLOW ALOFT DRIVING ELEVATED
MIXED LAYER ACRS THE AREA...RESULTING IN VERY WARM TEMPS ALOFT AND
POSSIBLY RESULTING IN STG CAPPING. ASSUMING CONVECTION SHUTS
DOWN...TEMPS WL LIKELY SOAR WELL INTO THE 80S WITH DWPTS RISING
INTO THE LOWER TO MIDDLE 70S. IF THAT OCCURS...A VERY VOLATILE ATM
COULD BE IN PLACE AS THE COLD FRONT STARTS IT/S PUSH ACRS THE AREA
THU AFTN/EVENING.
TOO MANY IF/S TO GET TOO SPECIFIC WITH THE FCST THIS FAR OUT...
BUT GIVEN THE OVERALL LOOK OF THE LARGE SCALE SET-UP...WL BEGIN TO
OPEN THE DOOR TO SOME SVR POTENTIAL IN THE HWO.
COOLER AND DRIER AIR WL PUSH INTO THE AREA IN THE WAKE OF THE
FRONT...AND LIKELY LINGER INTO EARLY NEXT WEEK.
NO SIG CHGS NEED TO BROAD-BASED EXTENDED FCST INITIALIZATION
GRIDS.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 636 PM CDT MON SEP 1 2014
CLEARING SKIES THIS EVENING AND DIMINISHING WINDS WILL LIKELY
LEAD TO GROUND FOG FORMATION LATE TONIGHT OVER N-C WISCONSIN. THE
GRADIENT IS A LITTLE TIGHTER OVER CENTRAL AND EAST-CENTRAL WI SO
SHOULD NOT SEE AS THICK OF FOG AS FURTHER NORTH. A WEAK
DISTURBANCE WILL THEN ARRIVE TUESDAY MORNING AND WILL PROVIDE A
SCT SHOWER THREAT BY MIDDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......TE
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SYNOPSIS...
ISSUED AT 233 PM CDT MON SEP 1 2014
WARM AND RATHER HUMID WITH SHOWERS AND THUNDERSTORMS AT TIMES
THROUGH MOST OF THE HOLIDAY-SHORTENED WORK WEEK.
STG SUBTROPICAL RIDGE ACRS THE SRN CONUS WL EXPAND NWD A BIT THE
NEXT FEW DAYS AS SEASONABLY STG AND PROGRESSIVE BAND OF WESTERLIES
TO IT/S N GRADUALLY RECEDES FARTHER NWD. THE PRIMARY FRONTAL ZONE
SEPARATING WARM AND VERY MOIST TROPICAL AIR TO THE S FM COOLER AND
DRIER CANADIAN AIR TO THE N WL REMAIN STETCHED OUT W-E ALONG THE
SRN EDGE OF THE MAIN WESTERLIES...AND CLOSE TO THE FCST AREA.
THIS WL RESULT IN SEVERAL OPPORTUNITIES FOR PCPN...LIKELY RESULTING
IN ABV NORMAL AMNTS. TEMPS AND HUMIDITIES ARE EXPECTED TO REMAIN
AOA NORMAL FOR THE NEXT SEVERAL DAYS...THEN DROP BACK CLOSE TO
NORMAL BY THE WEEKEND.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 233 PM CDT MON SEP 1 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A COLD
FRONT SLICING ACROSS NORTH-CENTRAL TO SOUTHWEST WISCONSIN EARLY THIS
AFTERNOON. PRIMARY AREA OF RAIN AHEAD OF A SHORTWAVE HAS EXITED
NORTHEAST WISCONSIN...BUT ARE SEEING SCATTERED SHOWER AND ISOLATED
THUNDERSTORM DEVELOPMENT ALONG THE COLD FRONT WHERE ML CAPE VALUES
ARE AROUND 400 J/KG. THIS FRONT WILL CONTINUE TO MARCH EAST THIS
AFTERNOON AND REACH EAST-CENTRAL WISCONSIN BY AROUND 00Z. WILL HAVE
TO KEEP A SCT SHOWER/ISOLD TSTORM MENTION AHEAD OF THE FRONT UNTIL
THEN. CLEARING SKIES EXIST BEHIND THE FRONT OVER FAR WESTERN
WISCONSIN AND MINNESOTA. THEN THE NEXT SHORTWAVE IS QUICKLY MOVING
EAST OVER WESTERN SOUTH DAKOTA WHERE A FEW LIGHTNING STRIKES ARE
OCCURRING. TIMING THE END OF PRECIP TONIGHT AND POTENTIAL FOR
THUNDERSTORMS TOMORROW ARE THE MAIN FORECAST CONCERNS.
TONIGHT...THE COLD FRONT WILL BE SLIDING SOUTHEAST ACROSS
EAST-CENTRAL AND SOUTHERN WISCONSIN EARLY IN THE EVENING...AND WILL
LEAVE A SLIGHT CHANCE OF SHOWERS OVER CALUMET...KEWAUNEE...AND
MANITOWOC COUNTIES FOR THE 00-01Z PERIOD. THEN SHOULD SEE A CLEARING
PERIOD THROUGH THE REST OF THE EVENING AS DRIER MID-LEVEL AIR WORKS
IN FROM THE WEST. A MODESTLY TIGHT PRESSURE GRADIENT WILL BE IN
PLACE FOR THE EVENING...BUT SHOULD LOOSEN OVERNIGHT...AND PROBABLY
ENOUGH FOR FOG FORMATION OVER N-C WISCONSIN. NOT AS CONFIDENT ABOUT
THE REST OF THE AREA AS STATISTICAL GUIDANCE IS RATHER PESSIMISTIC
ABOUT THE THREAT OF FOG. WILL KEEP A PATCHY MENTION ALONG THE WIS
RIVER VALLEY TOO. THE NEXT SHORTWAVE WILL BE MOVING INTO THE
NORTHERN MISSISSIPPI VALLEY LATE AND SHOULD HAVE INCREASING CLOUDS
TOWARDS SUNRISE. LOWS RANGING FROM THE LOW 50S NORTH TO NEAR 60S SOUTH.
TUESDAY...THE SHORTWAVE TROUGH WILL MOVE ACROSS WISCONSIN DURING THE
MORNING BEFORE EXITING BY MID TO LATE AFTERNOON. THERE MAY BE A
SPOTTY SHOWER WITH THE WAVE EARLY IN THE MORNING...BUT WITH DAYTIME
HEATING...MODELS PROJECT STEEP LOW LEVEL LAPSE RATES DEVELOPING ALL
THE WAY UP TO 750MB. CONVECTIVE TEMPERATURES ARE ONLY PROJECTED TO
REACH THE LOWER TO THE MIDDLE 70S...WHICH ARE SLIGHTLY BELOW THE
FORECASTED MAX TEMPS FOR THE DAY. IN ADDITION...ML CAPES ARE
PROJECTED TO RANGE FROM 500-1000 J/KG BY MIDDAY TO EARLY AFTERNOON
WITH NO CAP IN PLACE. AS A RESULT...SHOULD SEE ISOLATED SHOWERS
EARLY BECOME MORE SCATTERED BY MIDDAY AS CONVECTIVE TEMPS ARE
APPROACHED. WITH THOSE CAPES...CANNOT RULE OUT THUNDERSTORMS...AND
WILL KEEP A MENTION IN THE FORECAST. LOW FREEZING LEVELS AROUND
10KFT AND 0-6KM BULK SHEARS OF 30-35 KTS SUGGEST GUSTY WINDS AND
SMALL HAIL WILL BE POSSIBLE WITHIN ANY THUNDERSTORMS. HIGHS RANGING
FROM THE LOWER 70S NORTH TO UPPER 70S SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 233 PM CDT MON SEP 1 2014
ISOLD-SCT SHRA WL PROBABLY BE GONE BY TOMORROW NGT...SO WL START
THE LONG-TERM FCST OUT DRY. WK SFC PRESSURE GRADIENT AND 10-15 KT
WLY FLOW AT 850 MB WL NOT BE IDEAL FOR FOG TOMORROW NGT. BUT
GIVEN RECENT RAINS...WL MENTION PATCHY FOG ACRS THE AREA AFTER
MIDNIGHT.
QUIET WX SHOULD AT LEAST LINGER INTO WED...AND QUITE LIKELY LAST
THE WHOLE DAY. WL JUST BRUSH SOME LOW CHC POPS ACRS THE NW PART
OF THE AREA IN THE AFTN IN CASE SOME CONVECTION FM THE W CAN MAKE
IT THAT FAR E IN THE RELATIVELY FAST/FLAT WLY FLOW ALOFT.
A 24-36 HR PERIOD OF VERY ACTIVE WX WL PROBABLY FOLLOW FOR THE
LATTER HALF OF THE ABBREVIATED WORK WEEK. STG SHRTWV IN THE MAIN
BAND OF WESTERLIES WL BE PROGRESSING EWD ALONG THE U.S./CANADIAN
BORDER WED NGT...LIKELY RESULTING IN CYCLONGENESIS ACRS THE NRN
PLAINS. STRENGTHENING LLJ WL LIKELY VEER INTO THE FCST AREA
DURING THE NGT...PROBABLY BRINGING AN MCS FROM THE NRN PLAINS EWD
INTO THE FCST AREA. THE MAIN RESERVOIR OF VERY MOIST AND UNSTABLE
AIR WL BE TO THE SW...SO THE SVR THREAT WL MOST LIKELY REMAIN TO
OUR W. BUT WL NEED TO CLOSELY MONITOR THE SITN OVER THE NEXT FEW
DAYS AS THE FCST AREA WL BE ON THE ERN EDGE OF ELEVATED MIXED
LAYER...WITH FAIRLY STEEP MIDDLE LEVEL LAPSE RATES EDGING IN FM
THE W.
AS WAS THE CASE THIS MORNING AND BACK LAST MONDAY /AUG 25/...
CONVECTIVE POTENTIAL THU WL DEPEND ON THE BEHAVIOR OF THE
DEPARTING NOCTURNAL CONVECTION. WHAT MAY BE DIFFERENT THIS TIME
IS HIGHER UPR HEIGHTS AND STRONG WLY FLOW ALOFT DRIVING ELEVATED
MIXED LAYER ACRS THE AREA...RESULTING IN VERY WARM TEMPS ALOFT AND
POSSIBLY RESULTING IN STG CAPPING. ASSUMING CONVECTION SHUTS
DOWN...TEMPS WL LIKELY SOAR WELL INTO THE 80S WITH DWPTS RISING
INTO THE LOWER TO MIDDLE 70S. IF THAT OCCURS...A VERY VOLATILE ATM
COULD BE IN PLACE AS THE COLD FRONT STARTS IT/S PUSH ACRS THE AREA
THU AFTN/EVENING.
TOO MANY IF/S TO GET TOO SPECIFIC WITH THE FCST THIS FAR OUT...
BUT GIVEN THE OVERALL LOOK OF THE LARGE SCALE SET-UP...WL BEGIN TO
OPEN THE DOOR TO SOME SVR POTENTIAL IN THE HWO.
COOLER AND DRIER AIR WL PUSH INTO THE AREA IN THE WAKE OF THE
FRONT...AND LIKELY LINGER INTO EARLY NEXT WEEK.
NO SIG CHGS NEED TO BROAD-BASED EXTENDED FCST INITIALIZATION
GRIDS.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1156 AM CDT MON SEP 1 2014
THE MAIN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS WILL EXIT
NORTHEAST WISCONSIN EARLY THIS AFTERNOON. SOME SPOTTY SHOWERS ALONG
THE FRONT WILL LIKELY PASS OVER CENTRAL AND NORTH-CENTRAL WISCONSIN
THIS AFTERNOON BUT NOT SURE OF COVERAGE...SO LEFT OUT OF TAF SITES
FOR NOW. MVFR CIGS WILL TAKE A LITTLE LONGER TO MOVE
OUT...HOWEVER...BUT SHOULD STILL SEE CIGS IMPROVE MID TO LATE IN THE
AFTERNOON.
CLEARING SKIES THIS EVENING AND DIMINISHING WINDS WILL LIKELY LEAD
TO GROUND FOG FORMATION LATE TONIGHT OVER N-C WISCONSIN. THE
GRADIENT IS A LITTLE TIGHTER OVER CENTRAL AND EAST-CENTRAL WI SO
SHOULD NOT SEE AS THICK OF FOG AS FURTHER NORTH. A WEAK DISTURBANCE
WILL THEN ARRIVE TUESDAY MORNING AND WILL PROVIDE A SCT SHOWER
THREAT BY MIDDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
BEACH HAZARDS STATEMENT UNTIL 9 PM CDT THIS EVENING FOR WIZ022-
040-050.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1110 PM MDT MON SEP 1 2014
.UPDATE...
ISSUED AT 558 PM MDT MON SEP 1 2014
UPDATED TO PULL POPS ACROSS THE PLAINS THIS EVENING BASED ON
RADAR AND RECENT HI-RES MODEL DATA. MOISTURE AND LOW CLOUDS
MAY BE POSSIBLE OVER THE FAR SOUTHEAST PLAINS LATE TONIGHT INTO
TUESDAY MORNING...BUT NO PRECIP IS EXPECTED AT THIS TIME. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 240 PM MDT MON SEP 1 2014
MAIN NEAR/SHORT-TERM METEOROLOGICAL ISSUES ARE
TEMPERATURES...LOCALIZED GUSTY WINDS AT TIMES AND LOCALIZED LOW-
GRADE POPS.
CWFA EXPERIENCING NEAR SEASONAL SEPTEMBER AFTERNOON TEMPERATURES IN
COMBINATION WITH GENERALLY SUNNY SKIES...ALTHOUGH SOME VARIABLE
CLOUDS NOTED OVER PRIMARILY HIGHER TERRAIN LOCATIONS.
IN ADDITION...WIND GUSTS EXCEEDING 30 MPH AT TIMES HAVE BEEN
OBSERVED OVER THE MOUNTAINS OF CHAFFEE COUNTY. RECENT RADAR RETURNS
INDICATE SHOWERS AND THUNDERSTORMS NEARING FAR NORTHEASTERN
COLORADO...WELL NORTH OF OUR CWFA.
LATEST COMPUTER SIMULATIONS...REAL-TIME DATA AND FORECAST MODEL
SOUNDINGS INDICATE THAT GENERALLY DRY CONDITIONS SHOULD CONTINUE
OVER THE MAJORITY OF THE FORECAST DISTRICT FROM LATE THIS AFTERNOON
INTO TUESDAY AFTERNOON...ALTHOUGH RECENT HRRR MODEL DATA SUGGESTS
THAT SHOWERS AND THUNDERSTORMS MAY THREATEN PORTIONS OF NORTHERN EL
PASO AND KIOWA COUNTIES AS WELL AS SECTIONS OF LAS ANIMAS AND BACA
COUNTIES FROM LATER THIS AFTERNOON INTO THIS EVENING.
FOR TUESDAY...THE HIGHEST PROBABILITY OF ISOLATED SHOWER AND
THUNDERSTORM ACTIVITY SHOULD BE NOTED OVER WESTERN HIGHER TERRAIN
LOCATIONS...PRIMARILY DURING THE AFTERNOON AND EVENING HOURS.
GUSTY...PRIMARILY HIGHER TERRAIN WINDS ARE ALSO ANTICIPATED AT TIMES
FROM LATER THIS AFTERNOON INTO TUESDAY WHILE ABOVE SEASONAL EARLY
SEPTEMBER AFTERNOON TEMPERATURES ARE PROJECTED TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 240 PM MDT MON SEP 1 2014
...HOT WITH LOW THUNDERSTORM CHANCES THROUGH EARLY THURSDAY THEN
COOLER WITH INCREASING THUNDERSTORM CHANCES...
TUESDAY EVENING INTO EARLY THURSDAY...THE AIR MASS OVER THE REGION
WILL BE QUITE WARM AND THE THUNDERSTORM CHANCES WILL BE LOW. COULD
BE SOME SPOTTY DRY THUNDERSTORMS AROUND TUESDAY EVENING...MAINLY
OVER THE MOUNTAINS. THEN...WEDNESDAY AFTERNOON...COULD BE SOME
SPOTTY DRY LINE ACTIVITY ACROSS THE FAR SOUTHEAST PLAINS. MODELS
HAVE BEEN BACK AND FORTH ON THIS SO CONFIDENCE IS A LITTLE LOW BUT
THE POSSIBILITY REMAINS ALIVE.
ON THURSDAY...THINGS START TO TRANSITION TO A COOLER...WETTER
PATTERN. MODELS HAVE BEEN PRETTY CONSISTENT ON THIS SO CONFIDENCE
IS INCREASING. IT STARTS WITH THE ARRIVAL OF A COLD FRONT THROUGH
THE EASTERN PLAINS THURSDAY AFTERNOON. THE FRONT PUSHES INTO THE
REGION AS THE RESULT OF AN UPPER DISTURBANCE MOVING THROUGH THE
NORTHERN ROCKIES AND PLAINS. AS THE FRONT MOVES IN...MOIST UPSLOPE
WINDS BEHIND THE FRONT GRADUALLY FIRE THUNDERSTORMS OVER AND NEAR
THE MOUNTAINS IN THE AFTERNOON...SOME OF WHICH WORK EAST ACROSS THE
PLAINS BY LATE IN THE DAY. WITH ADDED MOISTURE IN THE AIR AND
UPSLOPE WINDS...THE THREAT FOR STRONG STORMS WILL INCREASE THIS DAY.
FRIDAY THROUGH MONDAY...WE COULD BE DEALING WITH SOME RICH
SUBTROPICAL MOISTURE AT TIMES...JUST DEPENDING ON HOW THINGS TRACK
OVER THE NEXT FEW DAYS. RIGHT NOW...INDICATIONS ARE THAT FRIDAY AND
SATURDAY COULD BOTH BE PRETTY WET OVER THE REGION WITH CONCERNS OF
FLASH FLOODING. SUNDAY AND MONDAY STILL LOOK PRETTY WET FOR THE
MOUNTAINS...BUT THE PLAINS LOOK MORE STABLE WITH LESS ACTIVITY. ALL
OF THIS IS STILL SEVERAL DAYS AWAY AND HIGHLY SUBJECT TO
CHANGE...HOWEVER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1108 PM MDT MON SEP 1 2014
VFR CONDITIONS AT ALL THREE TERMINALS THROUGH THE NEXT 24 HOURS.
WINDS WILL BE DIURNALLY DRIVEN AND SHOULD REMAIN IN THE 10-15 KT
RANGE ON TUESDAY AFTERNOON ACROSS THE REGION. AN ISOLATED
THUNDERSTORM IS POSSIBLE ALONG THE CONTINENTAL DIVIDE TUESDAY
AFTERNOON WITH A VERY LOW PROBABILITY OF IMPACT AT KALS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
SHORT TERM...77
LONG TERM...LW
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
345 AM EDT TUE SEP 2 2014
.CURRENTLY...WEAK HIGH PRES EXISTS OVER EXTREME S GA WITH WEAK
TROUGH NEAR COASTAL GA. DEBRIS CLOUDS CONTINUE TO DISSIPATE AS LATE
NIGHT CONVECTION LINGERED LATE TONIGHT OVER INLAND AREAS. SLOW
DISSIPATION OF CLOUDS WILL ENSURE INLAND TEMPS WILL ONLY STEADILY
DECREASE TOWARD SUNRISE. ALOFT...MID LEVEL HIGH IS LOCATED OVER SRN
GA AS WELL...WITH NEARLY ZONAL FLOW OVER NE FL. SOME PATCHY FOG IS
BEING REPORTED NOW AND INCLUDED IN THE LATEST FCST BY SUNRISE. A FEW
SHOWERS ARE LOCATED AROUND 60 NM OR MORE OFFSHORE AND WILL LIKELY
PUSH A LITTLE FURTHER EWD OVER THE NEXT FEW HRS.
.SHORT TERM...
TODAY...A FAIRLY SIMILAR PATTERN TO YESTERDAY WITH MEAN LAYER HIGH
PRES CONTINUING JUST NW OF THE AREA AND MEAN FLOW FROM THE NE AND E.
MODELS GENERALLY SHOW THE E COAST SEA BREEZE FIRING SOME CONVECTION
BY LATE MORNING AND EARLY AFTN...PERHAPS A BIT EARLIER THAN PRIOR
DAYS. ISOLD TO SCT SHOWERS AND STORMS ARE FCST TO DEVELOP OVER THE
ERN ZONES BY NOON-1PM AND THEN GRADUALLY BLOSSOM AND DRIFT INLAND
AROUND 5 TO 10 MPH. THE HRRR MODEL SHOWS DEEPEST MOISTURE OVER SE GA
AND PORTIONS OF NE FL LATER TODAY AND WILL PLACE HIGH END CHANCE TO
LIKELY POPS IN THESE AREAS...MAINLY AFTER 2 PM. WARM TEMPS AT 850 MB
AROUND 18/19C STILL SUPPORT HIGHS IN THE LOWER TO MID 90S...YIELDING
HEAT INDICES UP TO 105 IN SE GA. PRECIP WILL SLOWLY FADE TONIGHT
WITH SCT COVERAGE INLAND AND MORE ISOLD TOWARD THE COAST. PATCHY FOG
WILL BE POSSIBLE FOR INLAND AREAS LATE IN THE NIGHT...USING
CONSENSUS OF GUIDANCE TOOLS.
WEDNESDAY...SOMEWHAT OF A TRANSITION DAY AS TROPICAL UPPER LEVEL
TROUGH OVER THE FL STRAITS AND BAHAMAS PUSHES WWD WHILE MID LEVEL
HIGH OVER GA LIFTS SLIGHTLY NWD. THIS SCENARIO WILL INCREASE MEAN
ELY WINDS AND ALLOW A QUICKER PUSH OF THE E COAST SEA BREEZE.
INITIALLY HIGH PWATS WILL DECREASE DURING THE LATTER HALF OF THE DAY
ACROSS OUR SERN ZONES AS A DRY SLOT MOVES NWWD OVER CENTRAL FL AND
EVENTUALLY INTO OUR SRN ZONES. OVERALL...A BIT LESS COVERAGE OF
SHOWERS AND STORMS...ESPECIALLY FOR THE COASTAL ZONES. RAIN CHANCES
PROGGED AT 20-30% COASTAL COUNTIES AND 30-40% INLAND. HIGHS AGAIN IN
THE LOWER TO MID 90S.
.LONG TERM...DEEPER MOISTURE WILL START ADVECT INTO THE REGION BY
LATE WEDNESDAY AND CONTINUE MORE EARNESTLY THROUGH THE END OF THE
WEEK. INVERTED MEAN MID LAYER INVERTED TROF AND TUTT WILL APPROACH
AND MOVE THROUGH THE REGION AND RESIDE EAST OF THE FL PENINSULA BY
EARLY THURSDAY. BEHIND THIS FEATURE ABOVE NORMAL CHANCES OF
PRECIPITATION...ESPECIALLY ACROSS NE FL WITH HIGHER END CHANCE OF
POPS THURSDAY AND FRIDAY AFTERNOON AND EARLY EVENING. GOING INTO
NEXT WEEKEND THE UPPER LEVEL RIDGE AXIS MAINTAINS THE SAME POSITION
AS THE CURRENT WX PATTERN WITH HIGH PRESSURE OVER SOUTHERN GEORGIA.
THIS MEAN HIGH PRESSURE AREA SLIDES NORTHEASTWARD OVER THE NE
SEABOARD DURING THE BEGINNING OF NEXT WEEK. THIS WILL ALLOW LIGHTER
SLY SFC WINDS TO CONTINUE EARLY NEXT WEEK WITH MERGING SEA BREEZES
IN THE AFTERNOON AND EARLY EVENING HOURS. ELECTED TO KEEP SCATTERED
SHWRS AND TSTMS NEXT WEEK WITH DEEP MOISTURE REMAINING INTACT.
TEMPERATURES WITHIN A COUPLE DEGREES OF NORMAL WILL PREVAIL.
&&
.AVIATION...PREVAILING VFR TODAY. OCNL MVFR VSBY EXPECTED AROUND GNV
AND VQQ TERMINALS 08Z-12Z. WITH POPS GENERALLY AT OR BELOW 50% WILL
MAINTAIN VCTS TSTMS EXCEPT FOR GNV WHERE PROBS ARE SUFFICIENTLY HIGH
TO GO WITH TEMPO GROUP BY 21Z.
&&
.MARINE...S/SE WINDS UNDER 15 KT WILL PREVAIL INTO THE UPCOMING
WEEKEND WITH SEAS MAINLY 2-3 FT. ISOLATED SHOWERS/TSTMS WILL PREVAIL
THROUGH MIDWEEK...WITH SOME INCREASE LATE WEEK AS A WEAK WAVE
APPROACHES THE WATERS.
RIP CURRENTS: GENERAL LOW RISK THROUGH WEDNESDAY WITH FAIRLY SMALL
SWELLS AROUND 1-2 FT AND WEAK ONSHORE EXCEPT FOR BRIEF WIND INCREASE
ASSOCD E COAST SEA BREEZE IN THE AFTERNOONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 95 73 95 73 / 60 30 40 30
SSI 89 76 88 76 / 30 10 20 10
JAX 92 73 92 73 / 40 20 30 20
SGJ 88 74 88 75 / 30 10 20 10
GNV 92 71 92 71 / 50 30 30 30
OCF 92 71 93 71 / 50 30 40 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/CORDERO
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
358 AM CDT TUE SEP 2 2014
...UPDATED SHORT TERM SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 357 AM CDT TUE SEP 2 2014
AS OF 0845 UTC, STRONG THUNDERSTORMS WERE UNDERWAY ACROSS
COMANCHE, BARBER, AND CLARK COUNTY, TIED MOST CLOSELY TO A ZONE
OF FRONTOGENESIS AT AROUND 750MB STRETCHING FROM THE OKLAHOMA
PANHANDLE EAST- NORTHEASTWARD TO FAR SOUTH-CENTRAL KANSAS. THE
HIRES CONVECTIVE- ALLOWING MODELS PICKED UP ON THIS QUITE WELL IN
THE COMPOSITE REFLECTIVITY AND QPF FIELDS. THESE MODELS SHOW THE
CONVECTION MOVING OFF INTO NORTHERN OKLAHOMA BEFORE 1200 UTC, SO
WE WILL TAPER THE POPS DOWN AROUND THIS TIME. EARLIER IN THE
SHIFT, WE ADDED SOME AREAS OF 1/2SM FOG GENERALLY ALONG/SOUTH OF
THE ARKANSAS RIVER IN A ZONE OF SATURATED SURFACE AIR NORTH OF THE
WEAK SURFACE LOW. ANY FOG WHICH DEVELOPS SHOULD ERODE NOT TOO LONG
AFTER SUNRISE, HOWEVER LOW STRATUS IS EXPECTED TO HOLD ON THROUGH
LATE MORNING NORTH OF THE 850MB LOW. THIS MAY THROW A BIT OF A
CURVE BALL IN THE TEMPERATURES TODAY, SO WE ADJUSTED THEM DOWN
(USING A MODIFIED HRRR SOLUTION) OUT ACROSS THE WESTERN HALF FOR
THE FIRST HALF OF THE DAY WITH CLOUDS KEEPING A LID IN THE WARM-
UP. ONCE THE CLOUDS ERODE COMPLETELY BY MIDDAY/EARLY AFTERNOON,
TEMPERATURES WILL WARM INTO THE MID 80S. ANY SURFACE-BASED
CONVECTION LATE THIS AFTERNOON WILL BE DOWN ALONG THE SURFACE
FRONT ACROSS NORTHWEST OKLAHOMA. BY EARLY EVENING, SOME OF THE
THUNDERSTORM ACTIVITY MAY HEAD UP INTO BARBER COUNTY AND EXPAND IN
COVERAGE SOME AS LOW LEVEL JET STRENGTHENS AFTER SUNSET. RICH LOW
LEVEL MOISTURE LEADING TO 2000-3000 J/KG MOST-UNSTABLE CAPE WILL
SUPPORT RENEWED SEVERE WEATHER RISK, EVEN WITH ELEVATED STORMS
DURING THE LATE NIGHT HOURS TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM CDT TUE SEP 2 2014
THE LONGWAVE SYNOPTIC FLOW PATTERN WILL BE SOMEWHAT PROGRESSIVE
THROUGH THIS FORECAST, AT LEAST ENOUGH TO BRING SIGNIFICANT SENSIBLE
WEATHER CHANGES TO THE AREA FOR LATE IN THE WEEK. WEDNESDAY AND
THURSDAY WILL SEE SUNNY AND VERY WARM TO HOT TEMPERATURES, AS THE
UPPER JET LIFTS NORTHWARD ACROSS THE NORTHERN TIER OF STATES
ALLOWING THE LARGE SOUTHERN ROCKIES/SOUTHERN PLAINS HIGH PROVIDE
STRONG SUBSIDENCE, FULL INSOLATION AND SOUTHERLY SURFACE WINDS.
THE ECMWF/GFS AND NAM ARE IN EXCELLENT AGREEMENT IN BREAKING DOWN
THIS PATTERN BY THURSDAY AND BRINGING A COLD FRONT THROUGH THE
NORTHERN PLAINS OF WESTERN NEBRASKA AND AS FAR SOUTH AS WEST
CENTRAL KANSAS WITH THE LEADING COOLER AIR SURGE BY THURSDAY
AFTERNOON. CONVECTION COULD OCCUR LATE THURSDAY AFTERNOON OR
EVENING AS WELL WITH THIS COLD FRONT FEATURE, BUT UPPER
SUPPORT/DYNAMICS FOR WIDESPREAD STORM DEVELOPMENT IS LACKING. THE
UPPER JET WILL SINK SOUTHWARD THROUGH THE CENTRAL PLAINS AND
CENTRAL MISSISSIPPI VALLEY, DRIVING THE COLD FRONT FARTHER SOUTH
INTO THE SOUTHERN PLAINS BY SATURDAY MORNING. THE RESULT WILL BE
ADDITONAL CHANCES FOR POSSIBLY EVEN SEVERE STORMS, BUT PERHAPS
JUST POST SURFACE FRONTAL HIGH BASED CONVECTION FROM MID LEVEL
FRONTOGENESIS FRIDAY OR FRIDAY NIGHT WITH MUCH MORE PLEASANT
TEMPERATURES IN THE 70S.
A SLOW WARMING TREND IS LIKELY THROUGH THE LATE PART OF THE WEEKEND
INTO EARLY NEXT WEEK AS RETURN SOUTHERLY FLOW BECOMES REESTABLISHED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1249 AM CDT TUE SEP 2 2014
SCATTERED SHOWERS AND THUNDERSTORMS ALONG AN ELEVATED FRONTAL
BOUNDARY ABOUT 7000 FT AGL WILL BE CLOSE ENOUGH TO GCK, DDC, AND
EVEN HYS TO JUSTIFY A VCTS GROUP FOR A FEW HOURS OVERNIGHT.
OTHERWISE, WE EXPECT SOME LOW STRATUS TO DEVELOP IN WEAK, BUT
MOIST UPSLOPE FLOW, ESPECIALLY AT GCK AND DDC, SO WE WILL INCLUDE
SOME IFR (AND BRIEFLY LIFR AT GCK) IN THE 10-14Z TIME FRAME
ROUGHLY. THE STRATUS LAYER WILL LIFT IN CEILING AFTER SUNRISE,
HOWEVER IT IS STILL SOMEWHAT UNCLEAR HOW LONG IT WILL TAKE TO
SCATTER OUT. SOME OF THIS LOW STRATUS WILL ADVECT NORTHWARD TO HYS
LATE MORNING, SO WE WILL FORECAST SOME MVFR 1000-1500 CEILING FROM
LATE MORNING UNTIL EARLY AFTERNOON UP THERE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 87 68 98 71 / 20 10 0 0
GCK 87 67 100 71 / 10 10 0 10
EHA 87 66 99 69 / 10 0 10 10
LBL 87 69 100 72 / 10 10 0 10
HYS 86 67 99 73 / 10 10 10 10
P28 90 72 98 74 / 40 30 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...RUSSELL
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1155 PM CDT Mon Sep 1 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Tuesday)
Issued at 319 PM CDT MON SEP 1 2014
Quick cyclonic upper flow remains in place with the core of last
night`s wave already in the Great Lakes and another weaker wave
coming into the High Plains per recent water vapor imagery. The cold
front`s location is hard to nail down behind outflow from the
overnight convection and weak pressure fields, but appears to be
bisecting the local area from southwest to northeast. Lower cloud
under a modest inversion has been rather prevalent today, keeping
temps in the 70s.
Modest convergence persists in east central Kansas this afternoon.
With still some CIN remaining per RAP analysis, confirmed by recent
visible satellite imagery, and the western upper wave staying well
north, storm chances don`t look great, but will maintain some
mention ahead of the front in east central Kansas, diminishing with
time as weak high pressure continues to move across northern sections
of the state. There are some breaks in the clouds to the south, and
some increase in instability is anticipated for the next few hours.
Deep layer is not very high in the weak low level wind fields, but
hard to completely rule out with mixed layer CAPE likely rising to
near 1500 J/kg. As the surface high builds in, winds should be
rather light, and depending on cloud trends particularly with
convection, a fairly good setup for radiational fog will be in place
with cloudy skies and limited mixing today and low cloud scouring
out following the recent heavy rain. Will go ahead with some patchy
fog mention at this point and let later shifts watch trends. Storm
chances continue to look like Tuesday but with the boundary again
possibly not far south, will keep a small chance near it. Better
mixing and insolation should yield highs back into the 80s.
.LONG TERM...(Tuesday Night through Monday)
Issued at 319 PM CDT MON SEP 1 2014
Models continue to show the potential for elevated thunderstorms
and large hail Tuesday night. The one wrinkle is the NAM appears to
be quite a bit stronger in magnitude for both the elevated
instability and effective shear. There is still good theta-e
advection along the nose of the low level jet as well as
isentropic upglide, so I think there should be some storms over
eastern KS. The question is whether they will be strong enough to
produce severe hail. Have continued with a chance POP through the
night and think the potential still exists for some severe storms.
It just may be more marginal than the NAM would suggest.
With the exception of some elevated precip possibly lingering
through the morning Wednesday, the forecast should quiet down as
the models keep the jet stream and synoptic scale energy north of
the forecast through Thursday morning. By Thursday night, a frontal
system is projected to begin moving into the area. There is some
uncertainty in the timing of the frontal system as most solutions
have trended faster with the front, the NAM being the fastest. For
now I`ve not made many changes from the previous forecast thinking
the front would move through mainly Friday and Friday evening with
the higher chances for precip in these periods. However if the
faster trend continues, the POPs may need to be pushed up in the
forecast as well. Have continued to trend POPs down for Saturday
and kept a dry forecast for Sunday with models showing surface
ridging and relatively dryer air over KS. By Monday, there is some
disagreement with the GFS and ECMWF in the amplification of an
upper trough across the west. Because the GFS is the more
amplified solution, it is quick to set up return flow with the
potential for shortwaves within southwesterly flow aloft to pass
near the area. Have taken a conservative approach with the
forecast at this time and have introduced only a slight chance for
precip on Monday until there is a little more agreement in
solutions.
Temps will remain quite warm Wednesday and Thursday as the models
show the thermal ridge over portions of the state. Because of this
have continued with highs in the 90s and lows from around 70 to
the mid 70s. Cold air advection is expected to increase Thursday
night as the front moves through the area. This should bring a
cool down for the weekend with highs in the 70s and lows in the
50s to around 60.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1149 PM CDT MON SEP 1 2014
Elevated thunderstorms have moved well south and east of the taf
sites. Mid and high level clouds have blanketed the area from the
convection in southern KS, but they are slowly progressing
eastward. Once the clouds clear out there maybe brief periods of
patchy especially during calm winds in the predawn hours. Although the
forecast winds just above the surface may inhibit fog development.
Therefore did not add any tempo for dense fog at this time.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...65
LONG TERM...Wolters
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS JACKSON KY
418 AM EDT TUE SEP 2 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT TUE SEP 2 2014
PRESENTLY...A SHORTWAVE TROUGH IS PUSHING INTO THE OHIO RIVER VALLEY
REGION. AN MCS DEVELOPED YESTERDAY EVENING HEAD OF THIS TROUGH AND
IS NOW MARCHING EASTWARD INTO CENTRAL/SOUTHERN INDIANA...STRETCHING
BACK TO THE SOUTHWEST ACROSS SOUTHERN ILLINOIS. IR SATELLITE HAS
SHOWN SOME WARMING WITH THE CLOUD TOPS OVER THE PAST HOUR OR
TWO...INDICATING THAT THIS MCS MAY ALREADY BE ON THE DECLINE. IN
FACT...THE HRRR SUPPORTS THE IDEA OF A DYING MCS AS IT TRIES TO PUSH
INTO CENTRAL KENTUCKY TOWARDS DAYBREAK. CANNOT RULE OUT A FEW SHOWERS
PUSHING INTO THE BLUEGRASS SHORTLY AFTER 8 AM...BUT ANTICIPATE MORE
OF THE ACTION WITH THE SHORTWAVE TROUGH WILL COME LATER THIS
AFTERNOON AS WE GENERATE SOME INSTABILITY. WITH THIS IN MIND...PLAN
TO BACK OFF THE POPS THROUGH MIDDAY WITH JUST SOME ISOLATED SHOWERS
FOR AREAS NORTH OF I-64. OUTFLOW FROM THE DYING MCS WILL BE PUSHING
ACROSS EASTERN KENTUCKY EARLY THIS AFTERNOON...AND COULD KICK START
THE CONVECTION AS IT ENCOUNTERS SOME DECENT INSTABILITY. THE FORCING
ALOFT SHOULD ALLOW FOR FAIRLY GOOD SHOWER AND THUNDERSTORM COVERAGE
BY MID TO LATE AFTERNOON. WITH BULK SHEAR VALUES OF 30-40KTS THIS
AFTERNOON...A SEVERE THREAT WOULD EXIST AS THUNDERSTORMS COULD PUT
OUT SOME DAMAGING WIND GUSTS. THE SHEAR PROFILES WEAKEN BY MID
EVENING AND THE LOSS OF DAYTIME INSTABILITY SHOULD YIELD WEAKENING
STORMS AFTER 6 PM. HOWEVER...A FEW GUSTY WINDS MAY STILL BE POSSIBLE
THROUGH 8 OR 9 PM.
THE SHORTWAVE TROUGH WILL STALL A COLD FRONT ACROSS SOUTHERN
KENTUCKY BY LATE THIS EVENING. GIVEN THE PRESENCE OF THIS
BOUNDARY...AND PLENTY OF MOISTURE...IT MAY BE POSSIBLE TO SEE
ISOLATED SHOWERS THROUGH THE NIGHT ACROSS THE SOUTHERN HALF OF
KENTUCKY. THIS BOUNDARY WILL LINGER AROUND INTO WEDNESDAY AND WITH
INSTABILITY AGAIN RAMPING UP DURING THE AFTERNOON...WE COULD BE
LOOKING AT A FEW MORE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HOWEVER...BY WEDNESDAY...VERY LITTLE SHEAR IS
PRESENT...SO WE SHOULD SEE MORE ORDINARY THUNDERSTORMS WITH NO SEVERE
THREAT.
TEMPERATURES OVER THE NEXT 2 DAYS SHOULD BE FAIRLY SIMILAR TO WHAT WE
HAVE SEEN LATELY WITH HIGHS INTO THE LOW TO MID 80S. SAME CAN BE SAID
FOR LOWS TONIGHT WITH READINGS GENERALLY AROUND 70.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 418 AM EDT TUE SEP 2 2014
THE FRONTAL BOUNDARY REFERENCED IN THE SHORT TERM WILL BE DISSOLVING
EARLY IN THE LONG TERM PERIOD...BUT THERE SHOULD STILL BE DRY AIR IN
PLACE WEDNESDAY NIGHT...ESPECIALLY ALOFT. IF ANY CONVECTIVE PRECIP
CAN DEVELOP OFF OF LOW LEVEL MOISTURE ON WEDNESDAY AFTERNOON...IT
SHOULD DIE OUT BY NIGHT AS HEATING IS LOST AND SUPPORT ALOFT WILL
LIKELY BE LACKING.
DEEPER MOISTURE WILL MAKE A COMEBACK LATE IN THE WEEK AND MAY FUEL
A RESURGENCE OF SHOWERS AND THUNDERSTORMS...BUT A SUBTROPICAL RIDGE
ALOFT OVER THE SE CONUS WILL HELP TO KEEP COVERAGE LIMITED FOR A
WHILE. THE RIDGE WILL WEAKEN AND GET SUPPRESSED BY A BROAD TROUGH
DROPPING SE INTO THE NE CONUS DURING THE WEEKEND. THIS WILL ALLOW A
COLD FRONT TO MOVE INTO OUR REGION FROM THE NW. THE SCENARIO WILL
ALLOW AN INCREASE IN PRECIP COVERAGE...WITH A PEAK EXPECTED ON
SATURDAY. EVEN THOUGH THE FRONT SHOULD PASS BY SUNDAY...THE MODELS
STILL LEAVE SOME QUESTION AS TO HOW EFFECTIVE THE FRONT WILL BE AT
BRINGING IN A DRIER AIR MASS. HAVE HELD ONTO LOW POPS IN THE
AFTERNOON AND EVENING ON SUNDAY AND MONDAY...ESPECIALLY IN OUR SE
COUNTIES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 207 AM EDT TUE SEP 2 2014
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES OVER THE NEXT 24
TO 36 HOURS. A WEAK COLD FRONT WILL DROP SOUTH INTO EASTERN KENTUCKY
TODAY AND COULD SPAWN SCATTERED TO NUMEROUS THUNDERSTORMS. PLAN TO
STICK WITH THE VCTS THIS AFTERNOON AS TIMING AND UNCERTAINTY ARE TOO
GREAT TO GO WITH A THUNDERSTORM PREVAILING GROUP. ACTIVITY SHOULD
WANE BY MID TO LATE EVENING WITH A QUIET NIGHT EXPECTED TONIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
330 AM EDT TUE SEP 2 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT TUE SEP 2 2014
PRESENTLY...A SHORTWAVE TROUGH IS PUSHING INTO THE OHIO RIVER VALLEY
REGION. AN MCS DEVELOPED YESTERDAY EVENING HEAD OF THIS TROUGH AND
IS NOW MARCHING EASTWARD INTO CENTRAL/SOUTHERN INDIANA...STRETCHING
BACK TO THE SOUTHWEST ACROSS SOUTHERN ILLINOIS. IR SATELLITE HAS
SHOWN SOME WARMING WITH THE CLOUD TOPS OVER THE PAST HOUR OR
TWO...INDICATING THAT THIS MCS MAY ALREADY BE ON THE DECLINE. IN
FACT...THE HRRR SUPPORTS THE IDEA OF A DYING MCS AS IT TRIES TO PUSH
INTO CENTRAL KENTUCKY TOWARDS DAYBREAK. CANNOT RULE OUT A FEW SHOWERS
PUSHING INTO THE BLUEGRASS SHORTLY AFTER 8 AM...BUT ANTICIPATE MORE
OF THE ACTION WITH THE SHORTWAVE TROUGH WILL COME LATER THIS
AFTERNOON AS WE GENERATE SOME INSTABILITY. WITH THIS IN MIND...PLAN
TO BACK OFF THE POPS THROUGH MIDDAY WITH JUST SOME ISOLATED SHOWERS
FOR AREAS NORTH OF I-64. OUTFLOW FROM THE DYING MCS WILL BE PUSHING
ACROSS EASTERN KENTUCKY EARLY THIS AFTERNOON...AND COULD KICK START
THE CONVECTION AS IT ENCOUNTERS SOME DECENT INSTABILITY. THE FORCING
ALOFT SHOULD ALLOW FOR FAIRLY GOOD SHOWER AND THUNDERSTORM COVERAGE
BY MID TO LATE AFTERNOON. WITH BULK SHEAR VALUES OF 30-40KTS THIS
AFTERNOON...A SEVERE THREAT WOULD EXIST AS THUNDERSTORMS COULD PUT
OUT SOME DAMAGING WIND GUSTS. THE SHEAR PROFILES WEAKEN BY MID
EVENING AND THE LOSS OF DAYTIME INSTABILITY SHOULD YIELD WEAKENING
STORMS AFTER 6 PM. HOWEVER...A FEW GUSTY WINDS MAY STILL BE POSSIBLE
THROUGH 8 OR 9 PM.
THE SHORTWAVE TROUGH WILL STALL A COLD FRONT ACROSS SOUTHERN
KENTUCKY BY LATE THIS EVENING. GIVEN THE PRESENCE OF THIS
BOUNDARY...AND PLENTY OF MOISTURE...IT MAY BE POSSIBLE TO SEE
ISOLATED SHOWERS THROUGH THE NIGHT ACROSS THE SOUTHERN HALF OF
KENTUCKY. THIS BOUNDARY WILL LINGER AROUND INTO WEDNESDAY AND WITH
INSTABILITY AGAIN RAMPING UP DURING THE AFTERNOON...WE COULD BE
LOOKING AT A FEW MORE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HOWEVER...BY WEDNESDAY...VERY LITTLE SHEAR IS
PRESENT...SO WE SHOULD SEE MORE ORDINARY THUNDERSTORMS WITH NO SEVERE
THREAT.
TEMPERATURES OVER THE NEXT 2 DAYS SHOULD BE FAIRLY SIMILAR TO WHAT WE
HAVE SEEN LATELY WITH HIGHS INTO THE LOW TO MID 80S. SAME CAN BE SAID
FOR LOWS TONIGHT WITH READINGS GENERALLY AROUND 70.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 AM EDT TUE SEP 2 2014
LONG TERM DISCUSSION WILL FOLLOW SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 207 AM EDT TUE SEP 2 2014
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES OVER THE NEXT 24
TO 36 HOURS. A WEAK COLD FRONT WILL DROP SOUTH INTO EASTERN KENTUCKY
TODAY AND COULD SPAWN SCATTERED TO NUMEROUS THUNDERSTORMS. PLAN TO
STICK WITH THE VCTS THIS AFTERNOON AS TIMING AND UNCERTAINTY ARE TOO
GREAT TO GO WITH A THUNDERSTORM PREVAILING GROUP. ACTIVITY SHOULD
WANE BY MID TO LATE EVENING WITH A QUIET NIGHT EXPECTED TONIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
207 AM EDT TUE SEP 2 2014
.UPDATE...
ISSUED AT 207 AM EDT TUE SEP 2 2014
UPDATED TO REMOVE POPS FOR MOST AREAS THROUGH THE REMAINDER OF THE
NIGHT. THE MCS TO OUR WEST WILL APPROACH THE BLUEGRASS TOWARDS 8
AM...BUT MOST AREAS SHOULD STAY DRY UNTIL THEN. THIS MCS IS EXPECTED
TO DECAY THROUGH THE MORNING HOURS AND REALLY NOT MAKE IT VERY FAR
INTO EASTERN KENTUCKY IF IT MAKES IT AT ALL. MAY NEED TO WATCH FOR
REDEVELOPMENT ALONG THE OUTFLOW FROM THIS SYSTEM LATER ON TOWARDS
MIDDAY OR THE AFTERNOON. NO OTHER CHANGES PLANNED AT THIS TIME.
UPDATE ISSUED AT 1045 PM EDT MON SEP 1 2014
ISOLATED SHOWERS CONTINUE TO AFFECT NORTHERN KY...INCLUDING THE
NORTHERN PART OF THE JACKSON FORECAST AREA. THE SHOWERS HAVE SHOWN A
DECREASING TREND...AND THE TOTAL LIGHTNING DATA INDICATES THERE IS NO
LONGER ANY LIGHTNING IN KY. CONVECTION CONTINUES TO DEVELOP ACROSS MO
AND CENTRAL IL. BASED ON CURRENT TRENDS AND THE LATEST HRRR DATA THIS
COULD IMPACT OUR AREA BEGINNING SOMETIME NEAR OF AFTER 12Z. HOURLY
NDFD DATA HAS BEEN UPDATED FOR LATEST OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 751 PM EDT MON SEP 1 2014
ISOLATED THUNDERSTORMS CONTINUE TO AFFECT THE NORTHERN THIRD OF
KY...INCLUDING THE NORTHERN PART OF THE JACKSON FORECAST AREA. WITH
LOSS OF DAYTIME HEATING EXPECT THE ISOLATED CONVECTION TO CONTINUE TO
WANE. HOWEVER A SHORT WAVE MOVING INTO MO IS RESULTING IN AN
INCREASE IN SHOWERS AND THUNDERSTORMS AHEAD OF THE SURFACE COLD FRONT
THERE...AND THE REMNANTS OF THIS CONVECTION MAY AFFECT THE NORTHERN
PARTS OF THE FORECAST AREA LATE TONIGHT OR EARLY TUESDAY MORNING. THIS
IDEA IS SUPPORTED BY THE LATEST HRRR AND THE 18Z NAM AND GFS. HAVE
UPDATED NDFD FOR LATEST OBSERVATIONAL TRENDS AND WILL BE MAKING
ADDITIONAL ADJUSTMENTS TO HOURLY WEATHER GRIDS SHORTLY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 315 PM EDT MON SEP 1 2014
A LINE OF SCATTERED SHOWERS AND THUNDERSTORMS CONTINUES TO MOVE
ACROSS EASTERN KENTUCKY. THIS LINE IS OUT AHEAD OF THE COLD FRONT IN
THE WARM AIR. THERE IS A BIT OF CURVATURE TO THE LINE OF HEAVIEST
STORMS;...SO WILL BE WATCHING FOR SOME POTENTIALLY STRONG WIND GUSTS
AS THE LINE GOES THROUGH. THE MERCER AND LINCOLN COUNTY MESONET
SITES SAW WIND GUSTS OF 30 MPH AS THE LINE WENT THROUGH AND BATH
COUNTY SAW A GUST TO 41 MPH. CURRENT THINKING IS THE MAX GUSTS STAY
AROUND 40 MPH WITH THE STRONGEST STORMS AND MOST GUSTS WILL BE IN
THE 25 TO 35 MPH RANGE AS THE STORMS CONTINUE TO MOVE ACROSS EASTERN
KENTUCKY. THESE STORMS WILL DROP BETWEEN 0.25 TO 0.75 INCHES OF RAIN
AS IT MOVES ACROSS THE AREA. HAVE A LITTLE CONCERN FOR PARTS OF
EASTERN KENTUCKY THAT GOT HAMMERED LAST NIGHT FROM THE HEAVY
RAIN...HOWEVER THESE STORMS HAVE BEEN QUITE PROGRESSIVE AND HAVE NOT
YET SEEN ANY TRAINING OF THE ECHOES. THIS LINE SHOULD CONTINUE TO
MOVE ACROSS THE AREA AND THEN THE LEADING EDGE OF THE PREFRONTAL
PRECIPITATION WILL BE MOVING INTO THE AREA LATER TONIGHT. THE FRONT
WILL BE MOVING ACROSS THE AREA TOMORROW AND BRING WIDESPREAD SHOWERS
AND THUNDERSTORMS TO THE AREA. THERE WILL BE A SLIGHT RISK OF SEVERE
THUNDERSTORMS TOMORROW. SPC CURRENTLY HAS MOST OF EASTERN KENTUCKY
IN THE SLIGHT RISK AREA. THE MAIN THREAT WILL BE WINDS WITH A VERY
WEAK THREAT FOR MARGINALLY SEVERE HAIL. MOST LIKELY...ANY HAIL WILL
STAY IN THE 0.5 TO 0.75 INCH RANGE. THE PRECIPITATION WILL DROP OFF
FAIRLY QUICKLY BEHIND THE FRONT. THE MODELS ARE IN VERY GOOD
AGREEMENT WITH THE TIMING. WENT WITH THE MODEL BLEND FOR THE
TEMPERATURES WITH JUST SOME ADJUSTMENTS DUE TO ELEVATION.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 315 PM EDT MON SEP 1 2014
THE MODELS BEGIN THE EXTENDED PERIOD IN PRETTY GOOD AGREEMENT ONCE
AGAIN...WITH A RIDGE OF HIGH PRESSURE...BOTH ALOFT AND AT THE
SURFACE...CENTERED OVER THE EASTERN GULF OF MEXICO...ALONG WITH A
WELL DEFINED TROUGH OF LOW PRESSURE ALOFT TAKING SHAPE OVER THE
NORTHERN PLAINS. THE MODELS HAVE THE RIDGE BREAKING DOWN
CONSISTENTLY TO BEGIN THE PERIOD...WITH SHOWERS AND STORMS POPPING
UP BENEATH IT ACROSS THE TENNESSEE VALLEY DOWN TO THE GULF. AS THE
TROUGH EVOLVES AND STRENGTHENS...IT WILL EJECT OUT OF THE PLAINS
WEDNESDAY NIGHT AND THURSDAY...AND PUSH ACROSS THE GREAT LAKES AND
OHIO VALLEY REGIONS. THE COLD FRONT TRAILING FROM THIS UPPER LOW
WILL END BEING OUR WEATHER MAKER FOR THE UPCOMING WEEKEND. THE FRONT
IS EXPECTED TO INTERACT WITH MOISTURE COMING OFF THE GULF OF MEXICO
ON SOUTHWESTERLY WINDS. THE FRONT WILL HAVE A DIFFICULT TIME MOVING
EASTWARD...HOWEVER...AS THE RIDGE DIGS IN A BIT JUST OFF THE
SOUTHEAST COAST AND FLOW ALOFT BECOMES MORE ZONAL. THERE WILL BE A
GOOD CHANCE OF RAIN FRIDAY MORNING THROUGH SUNDAY MORNING...AS LIFT
AND MOISTURE ALONG THE SLUGGISH FRONT SET OFF REPEATED ROUNDS OF
SHOWERS AND STORMS. THE RAIN SHOULD FINALLY MOVE OUT OF THE AREA
SUNDAY EVENING...AS THE FRONT FINALLY MOVES OUT OF THE AREA.
TEMPERATURES TO BEGIN THE PERIOD LOOK TO BE ABOVE NORMAL...WITH
HIGHS TOPPING OUT AROUND IN THE MID TO UPPER 80S WEDNESDAY THROUGH
FRIDAY. ONCE THE FRONT STALLS ACROSS THE AREA AND PRECIPITATION
BECOMES MORE WIDESPREAD...TEMPERATURES WILL LIKELY MAX OUT BELOW
NORMAL VALUES SATURDAY THROUGH MONDAY. HIGHS ON FRIDAY WILL BE
CLOSER TO NORMAL AS THE FRONT WILL STILL BE TO OUR WEST. ON SATURDAY
AND SUNDAY...THE POSITIONING OF THE FRONT WILL ALLOW FOR SOME COOLER
AND DRIER AIR TO FILTER INTO THE AREA. HIGHS ON SATURDAY SHOULD BE
CLOSE TO NORMAL...AS THE BULK OF COOL AIR SHOULD STILL BE TRAPPED
NORTH OF THE OHIO RIVER. ON SUNDAY...HOWEVER...ONCE WINDS HAVE
SHIFTED TO THE NORTH...TEMPERATURES WILL BE QUITE COOL...WITH
READINGS PEAKING IN THE MID TO UPPER 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 207 AM EDT TUE SEP 2 2014
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES OVER THE NEXT 24
TO 36 HOURS. A WEAK COLD FRONT WILL DROP SOUTH INTO EASTERN KENTUCKY
TODAY AND COULD SPAWN SCATTERED TO NUMEROUS THUNDERSTORMS. PLAN TO
STICK WITH THE VCTS THIS AFTERNOON AS TIMING AND UNCERTAINTY ARE TOO
GREAT TO GO WITH A THUNDERSTORM PREVAILING GROUP. ACTIVITY SHOULD
WANE BY MID TO LATE EVENING WITH A QUIET NIGHT EXPECTED TONIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...JJ
LONG TERM...AR
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
502 AM EDT TUE SEP 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 500 AM EDT TUE SEP 2 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD LOW AMPLITUDE
MID/UPPER LEVEL TROUGH THROUGH FROM THE NRN PLAINS INTO THE UPPER MS
VALLEY AND WRN GREAT LAKES WITH SEVERAL WEAK EMBEDDED SHORTWAVES.
ONE WAS LOCATED FROM SW MN INTO NW IA WHILE ANOTHER UPSTREAM SHRTWV
WAS MOVING THROUGH NORTH DAKOTA. AT THE SFC...WRLY FLOW PREVAILED
ACROSS UPPER MI BETWEEN A 987 MB LOW NEAR JAMES BAY AND A WEAK RIDGE
INTO THE CNTRL PLAINS.IR LOOP SHOWED MAINLY CLEAR SKIES ACROSS MOST
OF THE CWA BUT WITH INCREASING CLOUDS FROM MN INTO NW WI AND WRN
UPPER MI AHEAD OF THE SW MN SHRTWV.
TODAY...MOST OF THE FORCING ASSOCIATED WITH THE MN SHRTWV IS
EXPECTED TO REMAIN SOUTH OF UPPER MI. HOWEVER...THE COMBINATION OF
DAYTIME HEATING AND 850-600 MB LAPSE RATES TO NEAR 7.5C/KM AND LOW
LEVEL CONV ALONG LAKE BREEZE BOUNDARIES(ESPECIALLY OVER THE EAST)
WILL SUPPORT ISOLD/SCT SHRA BY THIS AFTERNOON. AS THE NORTH DAKOTA
SHRTWV NEAR BY MID TO LATE AFTERNOON SOME ADDITIONAL WEAK QVECTOR
CONV MAY ALSO CONTRIBUTE TO PCPN CHANCES. ALTHOUGH MLCAPE VALUES
INTO THE 400-800 J/KG RANGE WILL BE MARGINAL FOR TS...SOME ISOLD COULD
DEVELOP. WITH FREEZING HEIGHTS ONLY NEAR 9K-10K FT...SOME SMALL HAIL
MAY BE POSSIBLE.
TONIGHT...WITH THE LOSS OF DAYTIME HEATING AND THE SHRTWVS EXITING
TO THE EAST...ANY PCPN SHOULD QUICKLY DIMINISH. WITH THE FAST
MID/UPPER LEVEL FLOW ACROSS THE NRN CONUS...MODELS SUGGEST THAT
ANOTHER WEAK SHRTWV COULD MOVE THROUGH THE NRN LAKES AND PRODUCE
SOME LIGHT PCPN. HOWEVER...WITH VERY LIMITED MOISTURE AND LITTLE
INSTABILITY...CONFIDENCE IN ADDITIONAL PCPN DEVELOPING WAS LOW AND NO
ADDITIONAL RAIN WAS MENTIONED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 401 AM EDT TUE SEP 2 2014
THOUGH ACTIVE WEDNESDAY NIGHT INTO THURSDAY EVENING...THE REST OF
LONG TERM WILL BE QUIET AS HIGH PRESSURE DOMINATES FROM FRIDAY INTO
EARLY NEXT WEEK.
STARTING ON WEDNESDAY...WEAKER SHORTWAVES WORK THEIR WAY ACROSS
NORTHERN PLAINS AND TO UPPER GREAT LAKES BY LATE IN THE DAY IN A
ZONAL FLOW PATTERN ALOFT. LARGE SCALE LIFT IS PRESENT BUT THERE IS
NOT MUCH FOR A STRONGER SHORTWAVE AND ALSO OVERALL MOISTURE IS
LIMITED. BULK OF SHRA/TSRA LATER ON WEDNESDAY SHOULD STAY WEST OF
UPR MICHIGAN...MAINLY OVER CENTRAL AND SOUTHERN MINNESOTA CLOSER TO
SFC WARM FRONT AND BUILDING INSTABILITY. COULD SEE ISOLD SHRA/TSRA
OVER WESTERN LK SUPERIOR OR EVEN FAR WEST UPR MICHIGAN DUE TO
GENERAL H85-H7 WARM AIR ADVECTION AND MID-LEVEL MOISTURE ADVECTION.
TEMPS ON WEDNESDAY SHOULD PUSH INTO THE UPPER 70S OR LOWER 80S EVEN
WITH SCT-BKN MID CLOUDS IN THE AFTN.
POTENTIAL FOR PERIOD OF ACTIVE WEATHER WEDNESDAY NIGHT INTO THURSDAY
MORNING AS THE APPROACH OF A SFC LOW OVER THE NORTHERN PLAINS INCREASES
LOW-LEVEL JET /40 KTS AT H85/ INTO THE UPPER GREAT LAKES. SINCE THERE
IS NOT REALLY A STRONG SHORTWAVE MOVING THROUGH AT THAT TIME THOUGH...THINK
THAT THE BULK OF SHRA/TSRA WILL BE VCNTY OF WHERE LOW- LEVEL JET
INTERSECTS THE SFC-H85 WARM FRONT. BASED ON SFC WINDS AND DWPNTS...BEST
GUESS AT LOCATION OF THAT BOUNDARY IS FM CNTRL MN INTO WESTERN WI
WEDNESDAY NIGHT. MAX INSTABILITY BOTH IN TERMS OF MLCAPE AND ELEVATED
MUCAPE WILL BE MAXIMIZED OVER MUCH OF MINNESOTA AND INTO WISCONSIN
WITH INSTABILITY TRAILING OFF CONSIDERABLY INTO UPR MICHIGAN AND LK
MICHIGAN/LOWER MICHIGAN. MAJORITY OF MODELS INDICATE WIDESPREAD QPF
OVER UPR MICHIGAN WEDNESDAY NIGHT...BUT HAVE MY DOUBTS ON THIS AS
MOST OF THE HEAVY SHRA/TSRA COULD END UP FARTHER SOUTH ALONG WARM
FRONT AND ALSO BASED ON H85-H3 THICKNESSES WHICH...ALONG WITH FORWARD
PROPAGATING CORFIDI VECTORS...CAN BE USED TO DETERMINE GENERAL MOTION
OF AN MCS. SIMILAR TO EARLIER IN THE NIGHT...THERE IS STILL MID-LEVEL
MOISTURE ADVECTION FARTHER NORTH OF THE BOUNDARY THOUGH SO CANNOT
COMPLETELY RULE OUT SHRA/TSRA MAKING IT ACROSS UPR MICHIGAN. ANOTHER
FACTOR THAT COULD BUMP SHRA/TSRA FARTHER NORTH INTO THE CWA IS
INCREASING CAPPING THAT DEVELOPS IN THE H8-H7 LAYER OUT AHEAD OF THE
SFC LOW. AT THIS POINT THOUGH IT APPEARS THAT MAIN EXTENT OF CAPPING
WILL REMAIN BACK OVER THE CENTRAL PLAINS ON WEDNESDAY NIGHT.
GIVEN THE CONCERNS ABOUT TSRA OVERAGE...BACKED DOWN A BIT ON THE
HIGHER POPS WE HAD GOING BUT DID KEEP POPS HIGH CHANCE TO LOW END
LIKELY WITH BETTER CHANCES OVER THE WEST INITIALLY SHIFTING TO THE
EAST FOLLOWING THE TREND OF H7-H5 Q-VECTOR CONVERGENCE TIED TO
INITIAL WEAK SHORTWAVE AND ALSO WHERE THIS FORCING SYNCS UP WITH
GREATER MID-LEVEL MOISTURE TRANSPORT. TSRA INTENSITY SHOULD DIMINISH
INTO THE EAST BY LATE WED NIGHT INTO THURSDAY MORNING AS SHRA/TSRA
OUTRUN GREATER POOL OF INSTABILITY OVER MINNESOTA AND WISCONSIN.
FOR THURSDAY...RETAINED MUCH OF THE PREVIOUS FORECAST SHOWING TREND
TOWARD LOWER POPS BY LATE THURSDAY MORNING IN WAKE OF THE INITIAL
SHRA/TSRA MOVING EAST THEN POPS RAMPING BACK UP IN THE AFTN WITH
POSSIBLE ADDITIONAL SHRA/TSRA AHEAD OF APPROACHING COLD FRONT.
CAPPING SHOULD INCREASE MARKEDLY BY LATE MORNING/EARLY AFTN BASED
ON FORECAST SOUNDINGS SO THIS WILL IMPACT ADDITIONAL DEVELOPMENT OF
SHRA/TSRA. COULD GET QUITE WARM WITH EVEN JUST A LITTLE CLEARING.
MIXING TO H9 WITH SHARPER INVERSION AROUND THAT LEVEL SHOWN ON
SOUNDINGS MAY BE CONSERVATIVE BUT STILL RESULTS IN HIGHS AROUND 80
OVER MUCH OF CWA. NUDGED TEMPS UP INTO THE LOWER 80S AS A STARTING
POINT...BUT A MUGGY DAY /SFC DWPNTS 65-70/ WITH MID 80S IS CERTAINLY
POSSIBLE IN SOME AREAS. PRIMARY SHORTWAVE DRIVING THE COLD FRONT WILL
BE JUST NORTH OF MINNESOTA BY LATE THURSDAY AFTN. GIVEN THE WARM AND
HUMID AIRMASS...MLCAPES AHEAD OF THE FRONT OVER WEST HALF OF CWA
COULD PUSH OVER 2500J/KG...BUT MAIN QUESTIONS ARE HOW MUCH DEEPER
MOISTURE WILL BE AROUND AHEAD OF THE FRONT AND WILL CAPPING IN THE
H8-H7 LAYER BE TOO STRONG TO PROHIBIT SHRA/TSRA FROM DEVELOPING?
BASED ON CONSENSUS OF MODELS AND LATEST TRENDS...SEEMS THAT THERE IS
A RISK OF STORMS FORMING MID-LATE THURSDAY AFTN OVER THE WEST AND
AFFECTING REST OF CWA INTO THE EARLY EVENING AS BETTER MOISTURE IS
RE-INTRODUCED INTO THE AREA FM THE WEST/SOUTHWEST AND LIFT INCREASES
AND CAPPING DECREASES AS SHORTWAVE AND H5 SPEED MAX DRAW CLOSER. GIVEN
THE DEGREE OF INSTABILITY...IF STORMS FORM...SEVERE WEATHER POTENTIAL
IS ELEVATED AS 0-6KM SHEAR IS OVER 45 KTS AND 0-3KM SHEAR IS OVER 30
KTS. THE FORECASTED INSTABILITY...IF IT IS INDEED REALIZED...AND
SUCH SHEAR WOULD SUPPORT ROTATING/SUPERCELL TYPE STORMS AND ALSO
POTENTIAL FOR STORMS CONSOLIDATING INTO SEVERE WIND GUST PRODUCING
MCS ALONG THE COLD FRONT. A CONDITIONAL RISK ATTM...BUT CERTAINTLY
WORTH MONITORING AS WE GET CLOSER TO THIS TIME FRAME. SPC DAY3
OUTLOOK HIGHLIGHTS WI INTO WEST HALF OF UPR MICHIGAN WITH A 15 PCT
RISK FOR SEVERE /SLIGHT CATEGORICAL RISK/. WILL MENTION POTENTIAL
FOR SEVERE IN THE MORNING HAZARDOUS WEATHER OUTLOOK.
ONCE THE COLD FRONT SLIDES THROUGH ON THURSDAY NIGHT...ANY LINGERING
SHRA/TSRA WILL QUICKLY COME TO AN END BY THE OVERNIGHT SOUTH AND
EAST CWA. MAIN ISSUE LATE THURSDAY NIGHT INTO FRIDAY WILL BE GUSTY
NORTHWEST WINDS ON LK SUPERIOR AS IT BECOMES UNSTABLE IN THE 1000-900MB
LAYER. MIXED LAYER WINDS ARE OVER 30 KTS SO IT COULD BE GUSTY ALONG
THE LK SUPERIOR SHORE TO BEGIN THE DAY ON FRIDAY. DUE TO PRESSURE
RISES BTWN DEPARTING LOW AND APPROACHING HIGH...EVEN HIGHER WINDS
WOULD NOT BE OUT OF QUESTION. INCREASING WAVE ACTION WOULD ALSO LEAD
TO HIGH SWIM RISK ON BEACHES FROM MARQUETTE TO GRAND MARAIS.
QUIET WEATHER FOR THE WEEKEND AS IT LOOKS NOW. HIGH PRESSURE SETTLES
OVERHEAD AND STAYS IN PLACE INTO EARLY NEXT WEEK. TEMPS AT NIGHT MAY
DIP BLO 40 DEGREES IN THE INTERIOR. DAYTIME HIGHS WILL BE SEASONABLY
COOL IN THE 60S FOR MOST AREAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 122 AM EDT TUE SEP 2 2014
EXPECT VFR CONDITIONS TO PREDOMINATE THIS FCST PERIOD WITH
RELATIVELY DRY LLVL AIR SHOWN ON UPSTREAM RAOBS DOMINATING. AN
APRCHG UPR DISTURBANCE/DAYTIME HEATING AND DESTABILIZATION COULD
CAUSE SOME -SHRA AT SAW AND PERHAPS IWD THIS AFTN...BUT THE DRY LLVL
AIR SHOULD MAINTAIN PREDOMINANT VFR WX EVEN IF THE -SHRA OCCUR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 500 AM EDT TUE SEP 2 2014
WINDS WILL BE 20 KNOTS OR LESS THROUGH MOST OF THIS FORECAST PERIOD
EXCEPT FOR THU NIGHT INTO FRI WHEN WEST TO NORTHWEST WINDS BEHIND A
STRONG COLD FRONT WILL APPROACH 30 KNOTS. THIS WILL BE THE WHEN THE
STRONGEST WINDS OCCUR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1225 AM CDT TUE SEP 2 2014
.UPDATE...
ISSUED AT 1225 AM CDT TUE SEP 2 2014
ONLY MINOR TWEAKS WERE MADE TO THE ONGOING FORECAST.
CANADIAN RADAR SHOWS SCATTERED SHOWERS MOVING SOUTHEAST ACROSS THE
CANADIAN PRAIRIES. THE LATEST RUN OF THE HRRR (03 UTC) PICKS UP ON
THE CANADIAN ACTIVITY AND BRINGS A FEW ISOLATED SHOWERS ACROSS
THE NORTH THROUGH THE EARLY MORNING HOURS. UPDATED THE PRECIP
FORECAST TO REFLECT THE LATEST TRENDS.
LATEST TEMPERATURE OBSERVATIONS WERE NEARING OVERNIGHT FORECAST LOWS
ALREADY. WITH SEVERAL HOURS OF DIURNAL COOLING AHEAD...LOWERED THE
OVERNIGHT LOWS A FEW MORE DEGREES.
UPDATE ISSUED AT 938 PM CDT MON SEP 1 2014
SCATTERED/ISOLATED SHOWERS AND THUNDERSTORMS HAVE DIMINISHED OVER
THE LAST HOUR WITH THE LOSS OF DAYTIME HEATING. REMOVED EVENING
POPS FROM THE FORECAST AS A RESULT. ALSO ADJUSTED THE HOURLY
TEMP/DEWPOINT GRIDS BASED ON CURRENT OBS/TRENDS. THE UPDATED
PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 604 PM CDT MON SEP 1 2014
ISOLATED TO SCATTERED INSTABILITY SHOWERS AND THUNDERSTORMS WILL
CONTINUE TO DEVELOP THROUGH THE EARLY EVENING HOURS...MAINLY OVER
WESTERN NORTH DAKOTA. WITH VERY WEAK DEEP LAYER SHEAR IN
PLACE...THIS CONVECTION IS EXPECTED TO BE BRIEF AND SUB-SEVERE. IT
SHOULD END BY 03Z THIS EVENING...IF NOT SOONER.
AFTER MIDNIGHT...THE MESOSCALE MODELS PROG A WEAK WAVE AND
ATTENDANT LIGHT QPF TO SKIRT ACROSS THE CANADIAN BORDER COUNTIES.
AS A RESULT...WILL MAINTAIN SLIGHT CHANCE POPS ACROSS THE
EXTREME NORTHERN CWA AFTER MIDNIGHT. CONVECTION SHOULD BE BRIEF
AND REMAIN SUB-SEVERE IF IT EVEN MATERIALIZES.
OTHERWISE...JUST MADE A FEW COSMETIC ADJUSTMENTS TO THE HOURLY
SENSIBLE WEATHER GRIDS. THE UPDATED PRODUCTS WILL BE OUT SHORTLY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 247 PM CDT MON SEP 1 2014
CURRENT SURFACE ANALYSIS PLACES LOW OVER ONTARIO WITH HIGH OVER
THE PACIFIC NORTHWEST INTO THE CENTRAL ROCKIES. UPPER LEVEL
ANALYSIS PLACES BROAD TROUGH CENTERED OVER THE PLAINS WORKING
TOWARDS THE MIDWEST. MODEST SHORT WAVE WORKING THROUGH THE FLOW
NOW MAKING ITS WAY FROM EASTERN MONTANA INTO THE WESTERN DAKOTAS
STARTING TO PRODUCE SOME CONVECTION.
FOR THE REST OF THIS AFTERNOON INTO THIS EVENING...EXPECT SOME
SHOWERS AND THUNDERSTORMS TO CONTINUE TO DEVELOP THROUGH THE
AFTERNOON. EXPECT ANY ACTIVITY SHOULD REMAIN ON THE TAME SIDE WITH
WEAK INSTABILITY/SHEAR. MOST ACTIVITY SHOULD COME TO AN END THIS
EVENING WITH DIMINISHING INSOLATION...THOUGH SOME SHOWERS/STORMS
MAY LINGER THROUGH THE OVERNIGHT OVER FAR NORTHERN NORTH DAKOTA AS
ANOTHER WAVE MAKES ITS WAY THROUGH.
ON TUESDAY...A FEW SHOWERS/STORMS MAY CONTINUE OVER THE FAR NORTH
AS AFOREMENTIONED WAVE CONTINUES TO MAKE ITS WAY THROUGH. OTHERWISE
A QUIET DAY IS ON TAP AS LOW AMPLITUDE RIDGE STARTS TO WORK ITS
WAY INTO THE AREA. SLIGHTLY MILDER TEMPS ARE EXPECTED.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 247 PM CDT MON SEP 1 2014
THE EXTENDED MODEL SUITE IS IN GOOD AGREEMENT WITH A POSITIVELY
TILTED SHORTWAVE TROUGH CURRENTLY LOCATED/ELONGATED FROM 140W/60N
TO 150W/55N...TO SHIFT INLAND TUESDAY NIGHT. THIS TROUGH IS
FORECAST TO REMAIN NEUTRAL TO SLIGHTLY NEGATIVE TILTED AS IT
SLIDES ACROSS WESTERN AND CENTRAL NORTH DAKOTA WEDNESDAY
NIGHT/THURSDAY MORNING. THIS WILL BE THE TIME PERIOD WITH THE
HIGHEST POPS...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS.
HEAVIEST RAINFALL APPEARS TO OCCUR OVER NORTH CENTRAL NORTH DAKOTA
WITH AROUND 0.65 INCHES FORECAST FROM MOHALL TO STANLEY...AND FROM
MINOT TO NEAR GARRISON. NAM/GFS SOUNDINGS SHOW A STRONG CAP IN
PLACE THROUGH 00Z THURSDAY FOR KMOT/KBIS/KJMS...AND A WEAKER CAP
IN PLACE AT KISN/KDIK. HAVE CONFINED POPS TO MAINLY THE NORTHWEST
AND PORTIONS OF NORTH CENTRAL NORTH DAKOTA WEDNESDAY...WITH
SHOWERS AND THUNDERSTORMS INCREASING IN COVERAGE WEDNESDAY
EVENING AND NIGHT. A POTENT COLD FRONT SWEEPS THROUGH WEDNESDAY
NIGHT WITH THE UPPER TROUGH APPROACHING AND SLIDING THROUGH ON
THURSDAY. SPC HAS A SEE TEXT WHICH INCLUDES NORTH DAKOTA...HOWEVER
LIMITED LOW LEVEL MOISTURE PER AN EAST TO SOUTHEASTERLY FLOW MAY
INHIBIT ORGANIZED SEVERE THUNDERSTORMS FROM DEVELOPING. HOWEVER
STRONG 0-6KM SHEAR OF 55KT TO 60KT WILL BE IN PLACE AHEAD OF THE
UPPER TROUGH AND ALONG/AHEAD OF THE SURFACE COLD FRONT. THIS WILL BE
MONITORED CLOSELY.
STRONG COOLING AS THE H85 FRONT SLIDES THROUGH...WITH TEMPS COOLING
FROM AROUND +20C WEDNESDAY EVENING...TO +6C THURSDAY EVENING. EXPECT
THE GREATEST WARMTH TO OCCUR ACROSS SOUTHERN NORTH DAKOTA WEDNESDAY
AFTERNOON ALONG/AHEAD OF THE H85 THERMAL RIDGE AXIS. EXPECT HIGHS IN
THE LOWER 80S. THIS WILL BE REPLACED WITH WIDESPREAD HIGHS IN THE
60S...EXCEPT LOWER 70S IN THE FAR SOUTHERN JAMES RIVER VALLEY
THURSDAY. BREEZY NORTHWEST WINDS OF 15 TO 25 MPH WILL ALSO
MATERIALIZE BEHIND THE FRONT FOR THURSDAY. WITH THE UPPER TROUGH
SWINGING THROUGH THURSDAY...STILL EXPECT A CHANCE FOR SHOWERS AND
THUNDERSHOWERS MAINLY ACROSS THE NORTH.
THEREAFTER...FRIDAY THROUGH SUNDAY...DRY WEATHER WITH A SLOW
MODERATING TREND AS BROAD CYCLONIC NORTHWEST FLOW DOMINATES THROUGH
SATURDAY. THIS TRANSITIONS TO BROAD RIDGING SUNDAY AND HIGHS WARMING
INTO THE MID 70S. A SLIGHT CHANCE OF THUNDERSTORMS COULD RETURN BY
MONDAY BUT THE BETTER CHANCES ARRIVE TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1225 AM CDT TUE SEP 2 2014
VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGH THE TAF
PERIOD WITH PREDOMINATELY WEST SOUTHWEST WINDS AND SCATTERED HIGH
CLOUDS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...JJS
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
408 AM EDT TUE SEP 2 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE ACROSS THE AREA TODAY EXTENDING FROM LOW
PRESSURE TRACKING NORTHEAST ACROSS QUEBEC. HIGH PRESSURE WILL
EXPAND OVER THE OHIO VALLEY TONIGHT...THEN TO THE EAST COAST ON
WEDNESDAY. A WARM FRONT WILL LIFT NORTH ON THURSDAY AHEAD OF THE
NEXT LOW PRESSURE SYSTEM THAT WILL PASS NORTH OF THE GREAT LAKES
ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A SWATH OF RAIN CAN BE SEEN ON UPSTREAM RADARS SPREADING NORTHEAST
ACROSS INDIANA EARLY THIS MORNING. THIS RAIN WILL CONTINUE TO BE
PULLED NORTHEAST AHEAD OF THE SHORTWAVE ENERGY MOVING ACROSS THE
PLAINS. THE 00Z SOUNDING OUT OF ILX SHOWED QUITE A BIT OF DRY AIR IN
THE COLUMN AHEAD OF THIS DEEPER PUSH OF MOISTURE AND THIS NOW
RESIDES OVER THE FORECAST AREA EARLY THIS MORNING. THE STRONGER
MOISTURE ADVECTION IS FOCUSED NEAR 700MB AND THE DRIER LOW LEVEL AIR
MAY CAUSE SOME EVAPORATION INITIALLY. THE BETTER INSTABILITY WILL BE
LOCATED FARTHER SOUTH AND TRENDS HAVE BEEN FOR THE DEEP CONVECTION
TO RESIDE ON THE SE FLANK OF THE PRECIPITATION SHIELD. WILL CARRY A
HIGH POP FOR JUST ABOUT ALL AREAS THIS MORNING...ALTHOUGH WILL ONLY
CARRY A CHANCE OF THUNDERSTORMS(BETTER CHANCES OF THUNDERSTORMS WILL
BE LOCATED ALONG AND SOUTH OF INTERSTATE 70 IN CENTRAL OHIO).
PRECIPITATION AMOUNTS WILL GENERALLY BE A HALF INCH OR LESS.
LOW PRESSURE IS LOCATED JUST EAST OF JAMES BAY THIS MORNING WITH THE
TRAILING COLD FRONT STILL LOCATED NORTH OF LAKE ERIE. THIS WEAK
FRONT IS EXPECTED TO MOVE THROUGH TOLEDO AROUND NOON...CLEVELAND
EARLY THIS AFTERNOON AND YOUNGSTOWN BY LATE AFTERNOON. ALTHOUGH THE
INITIAL SURGE OF MOISTURE WILL EXIT TO THE EAST...THE FRONT WILL
INTERACT WITH THE LINGERING MOISTURE WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE EASTERN AREAS THIS AFTERNOON. THE STORM
PREDICTION CENTER HAS PLACED OUR SE TIER OF COUNTIES IN THE SLIGHT
RISK FOR SEVERE THUNDERSTORMS TODAY. EXPECTING A CONSIDERABLE AMOUNT
OF CLOUD COVER TO HAVE A LIMITING EFFECT ON HEATING/INSTABILITY
ALONG AND AHEAD OF THE FRONT THIS AFTERNOON. BETTER CHANCES OF
SEVERE WEATHER WILL BE LOCATED JUST SOUTH AND EAST OF THE AREA BUT
CAN NOT ENTIRELY RULE OUT A SEVERE STORM IF HEATING IS STRONGER THAN
EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
HIGH PRESSURE WILL EXPAND EASTWARD ACROSS THE OHIO VALLEY TONIGHT.
IT LOOKS LIKE A WEAK THERMAL TROUGH WILL LINGER OVER LAKE ERIE ON
THE NORTH SIDE OF THE HIGH THIS EVENING AND MAY PROVIDE ENOUGH
CONVERGENCE FOR A FEW SHOWERS TO DEVELOP OVER THE LAKE. LEFT A LOW
POP BOTH OVER THE LAKE AND ALONG THE EASTERN LAKESHORE FOR A PORTION
OF THE NIGHT. INLAND AREAS...ESPECIALLY OUR SOUTHERN COUNTIES COULD
SEE SOME FOG OR STRATUS GIVEN THE LINGERING BOUNDARY LAYER MOISTURE
COUPLED WITH CLEARING SKIES AND LIGHT WINDS. TEMPERATURES WILL
BOTTOM OUT IN THE UPPER 50S TO LOW 60S.
THE AIRMASS DOES NOT COOL MUCH WITH THE FRONTAL PASSAGE AND
TEMPERATURES ARE STILL EXPECTED TO BE A COUPLE DEGREES ABOVE NORMAL
ON WEDNESDAY. THE MAIN DIFFERENCE WILL BE FELT IN THE HUMIDITY WHICH
WILL BE LOWER AND MORE PLEASANT WITH DEWPOINTS NEAR 60 DEGREES.
MAINLY JUST SCATTERED CU ON WEDNESDAY ONCE ANY MORNING CLOUDS BURN
OFF.
HEIGHTS WILL REBOUND OVER THE AREA ON THURSDAY AND A WARM FRONT WILL
LIFT NORTH AHEAD OF THE NEXT LOW PRESSURE SYSTEM TRACKING OUT OF THE
PLAINS. THIS SYSTEM IS FORECAST TO TRACK ACROSS LAKE SUPERIOR THEN
CONTINUE NORTHEAST ACROSS ONTARIO AND QUEBEC. ENOUGH DRY AIR SHOULD
STILL BE IN PLACE ON THURSDAY FOR THE FORECAST AREA TO STAY DRY.
LEFT THE 20 POP IN THE FORECAST ON THURSDAY NIGHT AS MOISTURE DOES
START TO INCREASE ALTHOUGH THE MORE FOCUSED MOISTURE ADVECTION WILL
BE WELL TO THE NORTH. THE ASSOCIATED COLD FRONT WILL SINK SOUTH
TOWARDS THE AREA ON FRIDAY. LOWERED POPS DURING THE MORNING HOURS
AND ACROSS THE SOUTHERN COUNTIES THAT SHOULD STRUGGLE TO SEE ANY
PRECIPITATION UNTIL FRIDAY NIGHT. TEMPERATURES ON THURSDAY AND
FRIDAY WILL BE IN THE MID 80S...WITH A FEW SPOTS MAKING A RUN AT THE
UPPER 80S.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
NO BIG CHANGES TO THE MODELS FOR THE EXTENDED WITH GUIDANCE SHOWING
A COLD FRONT TO OUR SOUTH SATURDAY MORNING WITH DRIER AIR AND HIGH
MOVING IN FROM THE NORTH. DONT THINK THE DAY WILL BEGIN DRY HOWEVER
AS THE ECMWF REMAINS SLOWER THAN THE GFS IN MOVING MOISTURE OUT OF
THE AREA. WILL CONTINUE WITH CHANCE POPS THROUGH THE MORNING
SATURDAY BEFORE DROPPING TO A SLIGHT CHANCE ACROSS THE NORTH.
SATURDAY NIGHT THROUGH MONDAY LOOK DRY. TEMPS NEAR NORMAL AFTER AN
ABOVE NORMAL END TO THE WEEK.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
WEAK COLD FRONT TO OUR NORTHWEST WITH BEST GUESS POSITION FROM
CENTRAL LWR MI SW INTO MO. MCS ACROSS MO AND SRN IL WHILE A FEW
LINGERING SHOWERS ALONG WITH A LITTLE THUNDER ACROSS FAR EASTERN
ERIE COUNTY PA AND EAST INTO WRN NY. THAT ACTIVITY WILL CONTINUE
EAST OUT OF THE AREA OVER THE NEXT HOUR OR TWO. HRRR DOES SHOW
SOME REDEVELOPMENT OVER ERIE COUNTY AND WILL ACCOUNT FOR THAT IN
THE TAF. OTHERWISE MAINLY VFR ACROSS THE AREA THIS HOURS ALTHOUGH
THE HRRR DOES SHOW ACTIVITY TO OUR WEST MOVING INTO THE AREA
TOWARDS MORNING. EXPECT THE BULK OF THE CONVECTION TO REMAIN SOUTH
OF OUR AREA...TRACKING ACROSS CENTRAL AND SRN OHIO...HOWEVER SO
EXPECT SOME PRECIP TO EXTEND NORTH AND AFFECT THE AREA. BROUGHT
SHOWERS INTO KTOL/KFDY AROUND 10Z AND KCLE/KMFD 11-12Z AND KERI-
KYNG 14-15Z. ALSO INCLUDED VCTS BUT FOR NOW DID NOT INCLUDE THUNDER IN
TEMPO GROUPS. HELD ONTO MVFR CIGS THROUGH THE BALANCE OF THE
MORNING GIVEN DEEP HIGH RH ACROSS THE AREA. DRIER AIR SHOULD BEGIN
MOVING IN THROUGH THE AFTERNOON.
OUTLOOK...NON VFR LIKELY IN SHOWERS AND THUNDERSTORMS BY FRIDAY
EVENING INTO SATURDAY WITH THE NEXT COLD FRONT.
&&
.MARINE...
WILL BEGIN TODAY CLOSE TO SMALL CRAFT CRITERIA MAINLY EAST OF
CONNEAUT BUT FOR NOW WILL CONTINUE WITH A FORECAST JUST BELOW. WINDS
TODAY WILL BE FROM THE SOUTHWEST AHEAD OF A WEAK COLD FRONT DUE IN
LATE MORNING/EARLY AFTERNOON. WINDS WILL TURN WEST TO BRIEFLY
NORTHWEST BEHIND THE BOUNDARY. HIGH PRESSURE BUILDS IN TONIGHT AND
WEDNESDAY. THURSDAY THE HIGH WILL DRIFT EAST AND A LOW WILL BE
MOVING THROUGH THE NORTHERN PLAINS. THIS WILL AGAIN SETUP SOUTHWEST
FLOW ON THE LAKE THURSDAY INCREASING TO 10 TO 20 KNOTS. THE LOW WILL
MOVE THROUGH EASTERN CANADA FRIDAY DRAGGING A COLD FRONT ACROSS THE
LAKE DURING THE AFTERNOON. WINDS WILL TURN NORTHWEST FRIDAY NIGHT
AND SATURDAY BEHIND THE FRONT. ALTHOUGH CLOSE...NO NEAR TERM
HEADLINES FOR NOW. FRIDAY INTO SATURDAY WE COULD REACH SMALL CRAFT
CRITERIA AS WINDS TURN NORTHWEST.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
152 AM EDT TUE SEP 2 2014
.SYNOPSIS...
A COLD FRONT WILL REACH THE NORTHERN OHIO VALLEY BY DAYBREAK AND
CROSS THE REGION FROM THE NORTHWEST ON TUESDAY. HIGH PRESSURE WILL
BRIEFLY BUILD IN BEHIND THE FRONT...WITH DRY CONDITIONS EXPECTED
FOR WEDNESDAY. A RETURN TO SOUTHERLY FLOW WILL INCREASE THE THREAT
FOR SHOWERS AND STORMS AT THE END OF THE WEEK...CULMINATING ON
SATURDAY AS THE NEXT COLD FRONT CROSSES THE REGION.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
ONLY A FEW SHOWERS LINGERING IN THE FAR EASTERN ZONES AND THEY
WILL MOVE OUT BEFORE MIDNIGHT. SHOWERS AND STORMS OCCURRING IN THE
CENTRAL PLAINS WILL SPREAD EAST NORTHEAST TOWARDS THE REGION. HRRR
AND RAP MODELS SHOWING SOME TIMING DISCREPANCIES. BUT IT APPEARS
THAT ACTIVITY WILL NOT SPREAD INTO WESTERN ZONES UNTIL VERY LATE
TONIGHT. EXPECT ANY HEAVIER RAINFALL TO CLOSER TO THE END OF THE
PERIOD AND INTO TUESDAY. FORECAST LOWS LOOK REASONABLE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
BY THE TIME DAYLIGHT HOURS OF TUESDAY ROLLS AROUND...THE SYSTEM IS
EXPECTED TO SHIFT THE SW-NE AXIS MORE INTO THE CWA AND ALONG THE
I-71 CORRIDOR. AREAS THAT SAW EXCESSIVE RAINFALL ON SATURDAY MAY
BE HIT WITH ANOTHER SOAKER...BUT THE UNUSUALLY HIGH VALUES SHOULD
NOT MAKE ANOTHER APPEARANCE...AT LEAST OVER WARREN AND GREENE
COUNTIES. PRECIP DURING THE DAY OVER THE CWA WILL BE PROGRESSIVE
AND EXPAND SOUTHEAST TO COVER THE REST OF CWA BY THE AFTERNOON.
HIGH TEMPS WILL BE MUTED DUE TO THE RAINFALL...GENERALLY IN THE
LOW 80S...SOME MID 80S ARE POSSIBLE IF THE RAIN HOLDS OFF A FEW
HOURS OVER THE SOUTHEAST.
HIGH PRESSURE WILL BRIEFLY FILL IN BEHIND THE COLD FRONT AND
PROVIDE ENOUGH DOWNWARD MOTION TO HELP SCOUR OUT MOST OF THE CLOUD
COVER AND USHER IN SOME DRIER AIR. THE DRIEST AIR AND SUBSEQUENT
COOLER TEMPERATURES FOR TUESDAY NIGHT WILL BE FOUND ALONG AND
NORTH OF THE I-70 CORRIDOR...WITH THE AREA EAST OF COLUMBUS
GETTING THE BEST COOLING BOTH TUES AND WED NIGHTS. NORTH OF DAYTON
ON WED NIGHT WILL LIKELY BE INVOLVED WITH THE RETURNING WARMER AND
MORE MOIST AIR ON THE SOUTHERLY WINDS.
HIGHS ON WEDNESDAY WILL REACH THE LOW TO MID 80S ACROSS THE
REGION.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
PERIOD BEGINS WITH A WEAK WARM FRONT LIFTING UP THROUGH THE WRN OHIO
VALLEY. AS FRONT LIFTS UP ACROSS THE AREA THURSDAY...THERE WILL BE A
SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM.
BY FRIDAY...A CDFNT BEGINS TO PUSH THROUGH THE GREAT LAKES. MODELS
ARE SHOWING A RANGE ON THE FROPA TIMING. THE GFS IS THE
QUICKEST...WHILE THE ECMWF IS ON THE SLOWER END OF THE GUIDANCE.
BOTH MODELS SHOW FROPA FRIDAY NIGHT INTO SATURDAY MORNING WITH
CONTINUED PCPN CHANCES ON SATURDAY. PUT THE BEST POPS FRIDAY NIGHT
WITH 50 POP ACROSS THE REGION. REDEVELOPED THE PCPN SATURDAY MORNING
WITH 50 POPS ACROSS THE SOUTH...BUT LOWER POPS TO THE NW.
THE GFS DRIES THINGS OUT QUICKER SATURDAY NIGHT AS COMPARED TO THE
ECMWF WHICH LEAVES LINGERING PCPN CHANCES INTO SATURDAY NIGHT ACROSS
THE SOUTH. HELD ON TO 20 POPS FOR THE EVENING HOURS IN THE SOUTHEAST.
HIGH PRESSURE BUILDS ACROSS THE REGION SUNDAY INTO MONDAY.
WARM AND HUMID CONDITIONS ARE EXPECTED FOR THURSDAY AND FRIDAY.
HIGHS WILL BE IN THE UPPER 80S TO 90 WITH DEWPOINTS IN THE UPPER 60S
TO LOWER 70S. COOLER CONDITIONS SATURDAY WITH HIGHS RANGING FROM THE
MID 70S IN THE NORTH TO THE LOWER 80S IN NRN KY. BY SUNDAY AND
MONDAY...HIGHS WILL BE IN THE LOWER TO MID 70S ACROSS THE REGION.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SOME SPOTTY MVFR STRATUS IS STARTING TO DEVELOP ACROSS THE AREA AND
THIS COULD FILL IN A BIT MORE OVER THE NEXT HOUR OR SO. HOWEVER...THINK
THE QUICKLY THICKENING CIRRUS SHIELD SHOULD PREVENT IT FROM
BECOMING TOO WIDESPREAD. OTHERWISE...AN AREA OF SHOWERS AND
THUNDERSTORMS PROGRESSING EAST ACROSS EASTERN ILLINOIS AND WESTERN
INDIANA SHOULD APPROACH THE WESTERN TAF SITES TOWARD 09Z AND THE
EASTERN TAF SITES AROUND 11Z. PCPN IS ASSOCIATED WITH A GOOD LOW
LEVEL JET THAT IS FORECAST TO SHIFT EAST INTO OUR AREA THROUGH 12Z
BEFORE BEGINNING TO WEAKEN BETWEEN 12Z AND 15Z. THIS SHOULD ALLOW
FOR AN OVERALL WEAKENING TREND IN THE THUNDERSTORM INTENSITY/COVERAGE
THROUGH MID TO LATE MORNING AS IT PROGRESSES EAST ACROSS OUR AREA.
AS THIS INITIAL WAVE PUSHES EAST OF THE AREA...WE COULD SEE A LULL
IN THE PCPN FROM LATE MORNING INTO EARLY AFTERNOON. HOWEVER...AS
WE DESTABILIZE THROUGH THE AFTERNOON...EXPECT TO SEE SOME ISOLATED
TO SCATTERED THUNDERSTORM REDEVELOPMENT. DRIER AIR WILL PUSH IN
FROM THE NORTHWEST LATE THIS AFTERNOON INTO THIS EVENING...ALLOWING
FOR DECREASING CLOUDS THROUGH THE END OF THE TAF PERIOD.
OUTLOOK...MVFR TO IFR VISIBILITIES ARE POSSIBLE LATE TUESDAY NIGHT
INTO WEDNESDAY MORNING. THUNDERSTORMS POSSIBLE FRIDAY INTO
SATURDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...
SHORT TERM...FRANKS
LONG TERM...SITES
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
122 AM EDT TUE SEP 2 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE EAST ACROSS THE AREA ON TUESDAY. HIGH
PRESSURE WILL BUILD NORTH OUT OF THE GULF COAST STATES TUESDAY
THROUGH THURSDAY AND THEN MOVE TO THE EAST COAST. A WARM FRONT WILL
LIFT NORTH ACROSS THE REGION THURSDAY AS LOW PRESSURE MOVES EAST
ACROSS THE NORTHERN LAKES THURSDAY NIGHT. A COLD FRONT TRAILING FROM
THE LOW WILL SAG SOUTHEAST OVER THE REGION FRIDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE PREFRONTAL TROUGH
ARE LOCATED OUT OVER LAKE ERIE AND ARE MOVING WITH AN EAST-
NORTHEAST DIRECTION. THEREFORE THEY MAY CLIP ERIE COUNTY PA BEFORE
HEADING OFF TO NY. ALL OTHERS WILL BE PRIMARILY DRY ALTHOUGH
CANNOT RULE OUT A STRAY SHOWER/TS OVERNIGHT.
A COLD FRONT WAS LOCATED FAR TO THE WEST...NEAR CHICAGO. THE
BETTER CHANCE OF PRECIPITATION COMES MUCH LATER TONIGHT AS A WAVE
DEVELOPS ALONG THIS FRONT WITH SUPPORT OF AN UPPER LEVEL WAVE AND
JET MAX. A STEADIER RAIN WITH EMBEDDED THUNDER WILL BEGIN TO WORK
ITS WAY IN FROM THE FINDLAY AREA NORTHEAST TOWARD MORNING. THERE
IS SOME QUESTION AS TO HOW FAST IT CAN MOVE INTO THE AREA BEFORE 6
AM.
AREA WILL STILL BE IN THE WARM SECTOR OVERNIGHT AND EXPECT LOWS
ONLY IN THE UPPER 60S AND LOWER 70S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
MORNING SHORTWAVE WILL PULL NORTHEAST AND DIMINISH THE RAIN
CHANCES AS THE DAY GOES ON TUESDAY. THE BIGGEST QUESTION IS HOW
FAR NORTH THIS AREA OF RAIN TRACKS. HAVE TOLEDO IN THE CHANCE
CATEGORY...AND THE SOUTHEAST THIRD OF THE AREA IN CATEGORICAL
POPS. THE COLD FRONT WILL CROSS THE AREA DURING THE DAY ON
TUESDAY...WITH IMPROVEMENT FROM WEST TO EAST.
THE BROAD UPPER LEVEL TROUGH WILL BEGIN TO LIFT OUT OF THE AREA ON
TUESDAY ALLOWING FOR ZONAL FLOW TO DEVELOP FROM WEST TO EAST
THROUGH THIS PERIOD.
HIGH PRESSURE WILL BEGIN TO BUILD IN FROM THE GULF COAST STATES AND
BRING DRIER AIR TO THE REGION. THE HIGH PRESSURE WILL BECOME THE
DOMINATING WEATHER FEATURE THROUGH WEDNESDAY. A WARM FRONT WILL LIFT
NORTHEAST ALONG WITH SOME LIMITED MEAN 1000 TO 500 MB MOISTURE ON
THURSDAY AND WE COULD SEE A MINIMAL CHANCE FOR SHOWERS AND
THUNDERSTORMS BY THURSDAY NIGHT. WILL HOLD ON TO THE SLIGHT CHANCE
AT THIS POINT SINCE MOISTURE WILL BE SO LIMITED.
AIR MASS BEHIND THE COLD FRONT IS NOT THAT STRONG SO NOT EXPECTING
TOO MUCH IN THE WAY OF COLD AIR ADVECTION ON TUESDAY INTO TUESDAY
NIGHT. LOWS WILL DROP OFF HOWEVER ABOUT 10 DEGREES TUESDAY NIGHT AND
THEN BEGIN TO RECOVER WEDNESDAY AND WEDNESDAY NIGHT AS WARM AIR
ADVECTION BEGINS TO TAKE PLACE. FURTHER WARMING TAKES PLACE THURSDAY
AND THURSDAY NIGHT IN THE EARNEST WARM AIR ADVECTION. 850 MB
TEMPERATURES CLIMB FROM 16C ON TUESDAY BACK TO AROUND 20C BY
THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
MODELS IN FAIR AGREEMENT TODAY. WILL START TO SEE PRECIP CHANCES
INCREASE ON FRIDAY AS A MOIST SOUTHERLY FLOW DEVELOPS AHEAD OF A
COLD FRONT. FRIDAY NIGHT AND SATURDAY WILL BE WET AND THE LIKELY
POPS IN THE PREVIOUS FORECAST SEEM REASONABLE. THE COLD FRONT WILL
MOVE SOUTH ACROSS THE AREA SATURDAY AND PRECIP SHOULD END DURING THE
AFTERNOON. THERE WILL BE A DISTINCT AIR MASS CHANGE BEHIND THIS
FRONT WITH DEW POINTS DIPPING INTO THE 40S AND TEMPERATURES BECOMING
BELOW NORMAL. BY MONDAY...MORNING LOWS WILL BE IN THE 40S SOME AREAS
WITH HIGHS STRUGGLING TO GET TO 70. WITH HIGH PRESSURE OVERHEAD
THERE SHOULD BE A LOT OF SUNSHINE BOTH SUNDAY AND MONDAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
WEAK COLD FRONT TO OUR NORTHWEST WITH BEST GUESS POSITION FROM
CENTRAL LWR MI SW INTO MO. MCS ACROSS MO AND SRN IL WHILE A FEW
LINGERING SHOWERS ALONG WITH A LITTLE THUNDER ACROSS FAR EASTERN
ERIE COUNTY PA AND EAST INTO WRN NY. THAT ACTIVITY WILL CONTINUE
EAST OUT OF THE AREA OVER THE NEXT HOUR OR TWO. HRRR DOES SHOW
SOME REDEVELOPMENT OVER ERIE COUNTY AND WILL ACCOUNT FOR THAT IN
THE TAF. OTHERWISE MAINLY VFR ACROSS THE AREA THIS HOURS ALTHOUGH
THE HRRR DOES SHOW ACTIVITY TO OUR WEST MOVING INTO THE AREA
TOWARDS MORNING. EXPECT THE BULK OF THE CONVECTION TO REMAIN SOUTH
OF OUR AREA...TRACKING ACROSS CENTRAL AND SRN OHIO...HOWEVER SO
EXPECT SOME PRECIP TO EXTEND NORTH AND AFFECT THE AREA. BROUGHT
SHOWERS INTO KTOL/KFDY AROUND 10Z AND KCLE/KMFD 11-12Z AND KERI-
KYNG 14-15Z. ALSO INCLUDED VCTS BUT FOR NOW DID NOT INCLUDE THUNDER IN
TEMPO GROUPS. HELD ONTO MVFR CIGS THROUGH THE BALANCE OF THE
MORNING GIVEN DEEP HIGH RH ACROSS THE AREA. DRIER AIR SHOULD BEGIN
MOVING IN THROUGH THE AFTERNOON.
OUTLOOK...NON VFR LIKELY IN SHOWERS AND THUNDERSTORMS BY FRIDAY
EVENING INTO SATURDAY WITH THE NEXT COLD FRONT.
&&
.MARINE...
SOUTHWEST TO SOUTH FLOW WILL CONTINUE TILL A COLD FRONT CROSSES THE
LAKE ON TUESDAY. IT APPEARS SHOWERS AND THUNDERSTORMS WILL OCCUR ON
THE LAKE THIS EVENING AND AGAIN RIGHT AHEAD OF THE COLD FRONT EARLY
THURSDAY. SOME OF THE STORMS ON THE WEST END COULD BE STRONG THIS
EVENING. LOOKS LIKE SPEEDS AND WAVES WILL REMAIN JUST BELOW SMALL
CRAFT CRITERIA TONIGHT SO WILL HOLD OFF ON ANY ISSUANCE. THE FLOW
WILL BECOME WESTERLY BEHIND THE FRONT. HIGH PRESSURE WILL BUILD
OVER THE LAKE FOR THE MIDDLE PART OF THE WEEK RESULTING IN LIGHT AND
VARIABLE FLOW. THE SURFACE RIDGE WILL EVENTUALLY MOVE OFF TO THE
EAST ON THURSDAY ALLOWING A WEAK SOUTHERLY FLOW TO DEVELOP. S TO SW
FLOW WILL THEN GRADUALLY INCREASE TILL A COLD FRONT CROSSES THE LAKE
ON SATURDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY/OUDEMAN
SHORT TERM...LOMBARDY/OUDEMAN
LONG TERM...KUBINA
AVIATION...TK
MARINE...KUBINA
CONTINUE ON WITH THE FORECAST DISCUSSION...
IN A BASIC SENSE...THE MOVEMENT OF THUNDERSTORM SYSTEMS IS
CONTROLLED BY THE AVERAGE OF THE WINDS ALOFT...OFTEN REFERRED TO
AS THE STEERING WINDS. IN MOST CASES...THUNDERSTORMS WILL SIMPLY
MOVE IN THE DIRECTION IN WHICH THE WINDS ALOFT ARE BLOWING.
HOWEVER THE SECOND COMPONENT TO CONSIDER IS OFTEN REFERRED TO AS
THE PROPAGATION COMPONENT OF STORM MOTION. PROPAGATION INFLUENCES
STORM MOTION BY CHANGING THE DIRECTION OF MOTION OF A THUNDERSTORM
SYSTEM IN THE DIRECTION THAT NEW THUNDERSTORMS DEVELOP. THIS IS
THE MORE COMPLICATED FACTOR TO UNDERSTAND...BUT IN GENERAL...NEW
THUNDERSTORMS TEND TO DEVELOP IN THE OPPOSITE DIRECTION OF THE LOW
LEVEL JET. ON A DAY LIKE TODAY...WHERE THE STEERING WINDS ARE
SOMEWHAT LIGHT DUE TO UPPER LEVEL RIDGING OVER TEXAS...BUT THE
LOW-LEVEL JET IS RELATIVELY STRONG...THE PROPAGATION COMPONENT CAN
DOMINATE THE DIRECTION IN WHICH THE THUNDERSTORM SYSTEM MOVES. FOR
TODAY...THE STEERING WINDS ARE SOMEWHAT LIGHT AND WOULD INDICATE
AN EASTERLY STORM MOTION. THIS IS WHY THE STORMS ARE JUST SORT OF
SITTING THERE ALONG THE FRONT AS OF 3 AM. HOWEVER IF THIS RESULTS
IN A STRONG ENOUGH COLD POOL (A COLLECTION OF RAIN COOLED AIR)
THIS COLD POOL COULD START TO SURGE SOUTH...CAUSING NEW STORMS TO
DEVELOP IN THE OPPOSITE DIRECTION OF THE LOW-LEVEL JET. SINCE THE
LOW-LEVEL JET EXTENDS FROM OUR CWA TO THE FRONT...THE WHOLE
COMPLEX OF STORMS COULD START TO MOVE SOUTH DIRECTLY TOWARDS THE
RED RIVER...BUT WILL STILL MOVE AT LEAST SLIGHTLY TO THE EAST DUE
TO THE STEERING WINDS ALOFT. THIS IS A DRAMATIC SHIFT IN DIRECTION
FROM WHAT STORMS HAVE BEEN DOING OVERNIGHT...BUT IT MAKES SENSE IN
THE CONTEXT OF WHAT WAS DESCRIBED ABOVE.
THE MAIN POINT OF UNCERTAINTY THIS MORNING IS: WILL
THUNDERSTORMS BECOME ORGANIZED ENOUGH TO MOVE AS A SYSTEM?
THAT IS LARGELY UNKNOWN BECAUSE JUST LOOKING AT THE STORMS ON
RADAR IS NOT ENOUGH TO DETERMINE HOW STRONG THE COLD POOL WILL
GET...BUT THE FACT THAT THE HRRR AND THE TEXAS TECH WRF BOTH
ADVERTISE A DRAMATIC SHIFT TO THE SOUTH OF THUNDERSTORMS TOWARDS
THE RED RIVER AROUND SUNRISE GIVES CONFIDENCE IN THIS SOLUTION.
WENT AHEAD AND PLACED A VERY SMALL AREA OF 20 POPS IN THE FORECAST
FROM JUST NORTH OF SHERMAN EXTENDING TO THE SOUTHEAST INCLUDING
MUCH OF LAMAR COUNTY. IF THE STORMS DO MOVE TO THE SOUTH AS THESE
HIGH RESOLUTION MODELS INDICATE...THEY WILL BE IN THEIR
DISSIPATING STAGES BY THE TIME THEY CROSS THE RED RIVER WELL
AFTER SUNRISE THIS MORNING...SO NO STRONG OR SEVERE WEATHER IS
EXPECTED AT THIS TIME.
THIS AFTERNOON...MODELS CONTINUE TO CONSISTENTLY SHOW A SURGE OF
TROPICAL MOISTURE TO THE NORTHWEST FROM THE TX GULF COAST THIS
AFTERNOON. THIS SURGE OF MOISTURE APPEARS TO BE ASSOCIATED WITH A
SUBTLE BUT IMPORTANT MID-LEVEL WIND SHIFT ASSOCIATED WITH DOLLY
MOVING NORTHWEST TOWARDS THE NORTHERN MEXICO GULF COAST. THIS
DEEPER TROPICAL MOISTURE IS EXPECTED TO REMAIN SOUTH OF THE
INTERSTATE 20 CORRIDOR THIS AFTERNOON...SO REORIENTED POPS A BIT
TO HIGHLIGHT THE SOUTHERN HALF OF THE CWA. IN GENERAL...THERE IS
STILL NO OBVIOUS LIFT...SO THE COVERAGE OF STORMS WILL PROBABLY BE
ISOLATED IN NATURE...AND LEFT POPS AT THE 20 PERCENT LEVEL FOR NOW.
WEDNESDAY THROUGH FRIDAY...DOLLY IS EXPECTED TO MAKE LANDFALL OVER
NORTHERN MEXICO LATE THIS EVENING...AND THEN CONTINUE OFF TO THE
WEST-NORTHWEST THROUGH THE END OF THE WEEK. MODELS SEEM TO SEND
THE DEEPER MID-LEVEL TROPICAL MOISTURE PLUME TO THE WEST WITH
DOLLY...SO WENT AHEAD AND REMOVED POPS FROM THE FORECAST ON
WEDNESDAY AFTERNOON ACROSS THE SOUTHERN CWA AND LEFT THE REMAINDER
OF THE FORECAST DRY. WEAK UPPER LEVEL RIDGING IS THE DOMINANT
FEATURE DURING THIS TIME FRAME...SO EXPECT SUBSIDENCE TO WIN OUT
IN KEEPING THINGS DRY ACROSS NORTH AND CENTRAL TEXAS.
THIS WEEKEND...MODELS CONTINUE TO HINT AT A COLD FRONT MOVING
SOUTH OF THE RED RIVER SOMETIME SATURDAY AFTERNOON THROUGH SUNDAY
MORNING. MODELS STILL SEEM TO INDICATE THAT THE PRIMARY REASON
THAT THE FRONT MAKES IT SOUTH OF THE RED RIVER IS DUE TO
PERSISTENT THUNDERSTORM ACTIVITY ALONG THE FRONT LATE THIS WEEK.
IF THE FRONTAL MOTION IS REALLY DEPENDENT UPON PERSISTENT
THUNDERSTORM ACTIVITY...CONFIDENCE IN THE TIMING AND PLACEMENT OF
THE FRONT IS GOING TO REMAIN LOW UNTIL LATE THIS WEEK.
THE BIGGEST REASON FOR OPTIMISM IN THE FRONT MAKING IT THIS FAR
SOUTH IS OBSERVING WHAT HAPPENS TODAY. IF MCS ACTIVITY FROM THE
OK/KS BORDER ACTUALLY SURGES SOUTH THIS MORNING...IT BECOMES EASY
TO SEE HOW PERSISTENT STORMS TO OUR NORTH CAN SEND A STRONG
OUTFLOW BOUNDARY/FRONT ACROSS NORTH TEXAS UNDER WEAK RIDGING
ALOFT. THE FRONT IS MOST LIKELY TO BE IN PLACE OVER THE CWA ON
SUNDAY...SO LEFT POPS MAINLY ALONG AND NORTH OF INTERSTATE 20 ON
SATURDAY...AND KEPT THEM BROAD BRUSHED OVER THE ENTIRE CWA ON
SUNDAY.
EARLY NEXT WEEK...THE FRONT...ASSUMING IT MAKES IT HERE THIS
WEEKEND...WILL PROBABLY DISSIPATE BY MONDAY. BECAUSE THE FRONT
DOES NOT REPRESENT A TRUE AIRMASS REPLACEMENT...THAT IS...THERE IS
NO CANADIAN/OR SIGNIFICANTLY COOL AIR TO THE NORTH OF THIS
FRONT...IT WILL UNDERGO FRONTOLYSIS AND LOSE DEFINITION QUICKLY
UNDER RIDGING ALOFT. LEFT THE FORECAST FOR EARLY NEXT WEEK DRY AS
A RESULT.
CAVANAUGH
&&
.AVIATION...
/ISSUED 1130 PM CDT MON SEP 1 2014/
VFR CONDITIONS AREA-WIDE WILL BECOME BRIEFLY INTERRUPTED BY A
PERIOD OF MVFR DURING THE TUESDAY MORNING HOURS AS STRATUS SPREADS
NORTHWARD IN THE SOUTHERLY LOW LEVEL FLOW. WE HAVE NOW INCLUDED
MVFR CIGS INDISCRIMINATELY BASED ON THE MOST RECENT MODEL
DATA...WITH ONSET AT 08Z IN KACT AND 11-12Z IN THE METROPLEX. CIGS
SHOULD SCATTER OUT IN THE 15-17Z TIMEFRAME...OTHERWISE PERSISTENT
SOUTH TO SOUTHEAST WINDS CAN BE EXPECTED.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 97 77 96 77 96 / 5 5 5 5 0
WACO, TX 98 75 97 74 97 / 20 20 10 5 5
PARIS, TX 92 72 91 72 92 / 20 10 5 5 0
DENTON, TX 96 75 95 74 95 / 10 5 5 0 0
MCKINNEY, TX 95 74 94 74 94 / 10 5 5 5 0
DALLAS, TX 97 78 96 78 96 / 5 5 5 5 0
TERRELL, TX 96 76 96 75 96 / 10 10 5 5 0
CORSICANA, TX 97 76 96 75 96 / 20 20 10 5 5
TEMPLE, TX 98 72 97 73 97 / 20 20 10 5 5
MINERAL WELLS, TX 97 73 96 72 96 / 5 5 5 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
354 AM CDT TUE SEP 2 2014
.SHORT TERM...
(Today and Tonight)
Another mild night ongoing across West Central Texas, with south
winds remaining strong enough to keep temperatures from dropping
very much. Readings still right around 80 degrees at 3 AM (08Z).
Models do indicate that some patchy low cloudiness will develop by
sunrise and spread northward into the area, with low cloud satellite
imagery showing some of this starting to develop across portions of
Central Texas.
Another hot day in store for the area, with the upper level ridge of
high pressure in control. The 00Z NAM showed some convection across
West Central Texas this afternoon, but the GFS is dry. Both the TTU
WRF and the HRRR both show a similar pattern, scattered sea breeze
activity pushing well inland today, but dissipating at sunset across
Central Texas. Thus, will not insert PoPs into the forecast.
After readings above the 100 degree mark at San Angelo and
Abilene, models indicate a slight cooling at 850MB today as a
little cooler and more moist air mass from the Gulf of Mexico
slides into the area. Will keep afternoon highs below the 100
degree mark, but still a degree or two above guidance. Mild again
tonight as south winds keep temperatures from dropping very
quickly. Again, stayed just a little above guidance, as it has
been too cool for the last several days.
.LONG TERM...
Surface temperatures fall 2 to 3 degrees F Wednesday as 850 MB
temperatures fall another 1 to 2 degrees Celsius. Tropical Storm
Dolly in the Bay of Campeche is expected to move into Mexico
early Wednesday, and may send weak disturbances/moisture
northward to affect the I-10 corridor Thursday and Friday. This
is indicated mainly by the EC model, as the GFS model is dry and
the NAM model nearly so. Will keep rain chances out of forecast
for this time period, given the uncertainty and limited agreement
in the models.
For Saturday night into Sunday, however, both the GFS and EC
modes are still indicating a weak cold front to bring a slight
chance of showers and thunderstorms. Forecast already has rain
chances in for this time period, and will maintain them.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 100 76 96 74 95 / 5 5 5 5 5
San Angelo 98 75 95 74 94 / 5 5 10 10 10
Junction 95 77 93 74 93 / 10 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07/04
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
355 AM CDT TUE SEP 2 2014
.SHORT TERM...
3 AM TEMPS WERE STILL IN THE LOWER 80S ACROSS MUCH OF THE SOUTHERN
SOUTH PLAINS INTO THE ROLLING PLAINS...WHICH ISN/T SURPRISING GIVEN
THE RECORD-SETTING WARMTH ACROSS THE AREA ON LABOR DAY. A WEAK COLD
FRONT WAS LOCATED NEAR I-40...AND THERE WAS EVEN AN AREA OF LOW
CLOUDS DEVELOPING NORTH OF THE FRONT ACROSS THE OKLA AND NRN TX
PANHANDLES. ALOFT...A SHORTWAVE TROUGH IS MOVING FROM THE CENTRAL
PLAINS INTO THE MIDWEST...WITH ONLY A WEAK REFLECTION INTO THE SRN
HIGH PLAINS. THE FRONT IS EXPECTED TO MAKE SOME SWD PROGRESS THIS
MORNING ACROSS THE WEST BEFORE STALLING/WASHING OUT THIS
AFTERNOON...WITH A WEAK SURFACE LOW DEVELOPING ACROSS THE WESTERN
SPLNS. THIS IN TURN SHOULD PRODUCE A WEAKLY CONVERGENT ZONE FROM THE
CENTRAL SPLNS TO THE SOUTH-CENTRAL TX PANHANDLE...ALONG WITH A
DIFFUSE DRYLINE. WITH LITTLE IF ANY UPPER-LEVEL SUPPORT...WE/LL HAVE
TO RELY ON SURFACE-BASED LIFT TO GENERATE ANY MOIST CONVECTION
TODAY. KLBB FCST SOUNDING SHOWS A WEAKLY CAPPED PROFILE THIS
AFTERNOON...WITH NO CAP REMAINING FARTHER TO THE NORTH-NORTHEAST.
THERE IS NOT A WHOLE LOT OF QPF SIGNAL IN MODEL SOLUTIONS...BUT THE
06 UTC HRRR AND RAP RUNS INDICATE ISOLATED DEVELOPMENT AS WELL AS
THE SREF...WHICH SOMEWHAT BULLSEYES THE CAPROCK CANYONS AREA. WE
WILL RUN WITH A 15-20 PERCENT CHANCE OF T-STORMS...CENTERED ACROSS
BRISCOE COUNTY...AND ROUGHLY EXTENDING WEST TO I-27 AND SOUTH TO
NEAR HWY 82. SHEAR APPEARS TO BE TOO WEAK TO SUPPORT MORE THAN
PULSE-TYPE NON-SEVERE STORMS...BUT ML CAPES NEARING 2000 J/KG COULD
SUPPORT SMALL HAIL...LOCALIZED WIND GUSTS TO 50 MPH...AND A BRIEF
DOWNPOUR. STORMS SHOULD DIMINISH QUICKLY THIS EVENING WITH THE LOSS
OF SFC-BASED INSTABILITY. SKIES SHOULD BE MOSTLY CLEAR TONIGHT
ALTHOUGH SOME LOW STRATUS COULD INVADE FROM THE SOUTH EARLY WED
MORNING.
AS FOR TEMPS...FORTUNATELY WE SHOULD SEE THE HEAT OF THE PAST TWO
DAYS BACK DOWN A BIT...ALTHOUGH WE WOULDN/T BE SURPRISED TO SEE A
FEW LOCATIONS HIT 100 DEGREES IN THE LOW ROLLING PLAINS. HIGH TEMPS
MAY ONLY REACH THE LOWER 90S IN THE FAR SW TX PANHANDLE DUE TO THE
WEAK FRONT/S INFLUENCE...WITH MIDDLE TO UPPER 90S EXPECTED ELSEWHERE.
&&
.LONG TERM...
THE EXTENDED FORECAST FEATURES A WELCOME COOLING TREND EARLY ON WITH
INCREASING RAIN CHANCES BY THE WEEKEND.
INITIALLY...THE WESTERN EXTENT OF A LONGITUDINALLY BROAD UPPER RIDGE
WILL HOLD SWAY OVER WEST TEXAS MID/LATE WEEK. THIS RIDGE WILL
PROVIDE DRY AND WARM WEATHER...THOUGH DECREASING 1000-500 MB
THICKNESSES AND 850 MB TEMPERATURES PROMISE A GRADUAL COOLING TREND.
THINGS MAY EVENTUALLY BECOME MORE INTERESTING LATE WEEK INTO THE
WEEKEND THOUGH THIS WILL BE AT LEAST PARTIALLY CONTINGENT ON WHETHER
OR NOT A COLD FRONT MOVING THROUGH THE PLAINS CAN SETTLE INTO THE
SOUTH PLAINS. THE COLD FRONT WILL MAKE ITS FIRST RUN SOUTHWARD
BEHIND A POTENT SHORTWAVE TROUGH RIDING ACROSS THE NORTHERN TIER OF
THE NATION AND SOUTHERN CANADA WEDNESDAY AND THURSDAY. CURRENT NWP
HOLDS THE FRONT TO OUR NORTH ON FRIDAY...AS INCREASING AMOUNTS OF
TROPOSPHERIC MOISTURE /POTENTIALLY ENHANCED BY REMNANTS OF DOLLY
AND A TAP OFF A TROPICAL CYCLONE YET TO FORM IN THE EASTERN
PACIFIC/ ARE FUNNELED AROUND THE RIDGE INTO THE DESERT SOUTHWEST.
THE BEST RAIN CHANCES WILL LIKELY REMAIN FOCUSED TO NORTH AND WEST
FRIDAY INTO FRIDAY NIGHT...AND WE HAVE DECREASED POPS SOMEWHAT
OVER THIS PERIOD.
THE LATEST ITERATION OF THE GFS AND ECMWF NOW TEND TO KEEP THE UPPER
RIDGE CENTERED CLOSE ENOUGH THROUGH THE WEEKEND TO MAKE IT A LITTLE
MORE UNCERTAIN WHETHER WE WILL FULLY BE ABLE TO TAP THE SUB-TROPICAL
AND TROPICAL MOISTURE. EVEN SO...THE NWP SUGGESTS THE OUTFLOW
AIDED FRONT WILL SAG INTO THE SOUTH PLAINS SOMETIME OVER THE
WEEKEND /AS EARLY AS FRIDAY NIGHT WITH THE ECMWF OR NOT UNTIL
SATURDAY NIGHT IN THE GFS/. REGARDLESS...IF THE FRONT CAN MAKE IT
INTO THE CWA IT WILL BRING MORE SIGNIFICANT COOLING ALONG WITH
ENHANCED RAIN CHANCES. GIVEN THE UNKNOWNS...WE HAVE NOT MADE MANY
ADJUSTMENTS TO THE FORECAST OVER THE WEEKEND AND HAVE MAINTAINED
THE HIGHEST POPS SATURDAY NIGHT...WHEN CONFIDENCE IS HIGHEST OF
THE QUASI-STATIONARY FRONT RESIDING SOMEWHERE LOCALLY.
THE FRONT WILL THEN LIFT BACK NORTHWARD EARLY NEXT WEEK AS PRESSURES
FALL ACROSS THE HIGH PLAINS...DOWNSTREAM OF A WESTERN STORM SYSTEM.
THIS WILL RESULT IN WARMER AND DRIER WEATHER FOR WEST TEXAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 92 64 93 64 89 / 10 10 10 10 10
TULIA 95 67 94 66 90 / 20 10 10 10 0
PLAINVIEW 94 66 93 67 90 / 20 10 0 0 0
LEVELLAND 95 67 93 67 89 / 10 10 10 10 10
LUBBOCK 97 70 93 68 90 / 10 10 0 0 0
DENVER CITY 97 67 93 67 89 / 10 10 10 10 10
BROWNFIELD 97 68 93 68 90 / 10 10 0 0 10
CHILDRESS 98 72 97 73 96 / 10 10 0 0 0
SPUR 97 69 96 71 93 / 10 10 0 0 10
ASPERMONT 98 73 98 73 96 / 10 10 0 0 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33/23
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
149 AM EDT TUE SEP 2 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL REMAIN OVER THE REGION TONIGHT INTO MUCH
OF TUESDAY. A WEAK COLD FRONT TRACKS SOUTHEAST INTO OUR AREA BY
TUESDAY EVENING...BEFORE STALLING ACROSS THE CAROLINAS AND WASHING
OUT ON WEDNESDAY. HIGH PRESSURE SETS BACK UP OVER THE EAST BY
FRIDAY WITH YET ANOTHER COLD FRONT MOVING TOWARD US THIS WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 138 AM EDT TUESDAY...
MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND POPS FOR THIS
MORNING.
AS OF 850 PM EDT MONDAY...
OTHER FOR ISOLATED SHRA/TSRA PASSING ACROSS THE FAR
NORTH...CONVECTION REMAINS LIMITED THIS EVENING AS SOUNDINGS SHOW
WEAK CAPPING ALOFT WITHIN A DEEP WESTERLY FLOW REGIME. THIS ALONG
WITH LACK OF DEEP INSTABILITY SHOULD KEEP THINGS MAINLY QUIET
OVERNIGHT WITH JUST SOME PATCHY FOG IN THE VALLEYS AND PERHAPS OUT
EAST. HOWEVER WITH THE LATEST HRRR TRACKING THE CURRENT ISOLATED
COVERAGE OVER GREENBRIER EAST TOWARD THE SOUTHERN SHENANDOAH
VALLEY...WILL LEAVE IN SOME LOW POPS ACROSS THE EXTREME NORTH SINCE
HEADING INTO SOME DECENT LEFTOVER CAPE DESPITE LOSS OF HEATING.
WILL ALSO CONTINUE SOME LOW CHANCES FAR NW LATE FOR ACTIVITY
COMING IN AHEAD OF THE UPSTREAM FRONT AROUND DAYBREAK. OTRW FEW
CHANGES OTHER THAN TO INCLUDE A BIT OF FOG AND BUMP UP TEMPS IN
SPOTS GIVEN SUCH A MUGGY OVERNIGHT.
ANOTHER SHORTWAVE AHEAD OF A FRONT SHIFTING SE INTO THE OHIO VALLEY
PASSES ACROSS TUESDAY MORNING. FOR NOW IT LOOKS LIKE THE WESTERN CWA
WILL SEE A CHANCE OF SHOWERS/ISOLATED TSRA DURING THE MORNING BUT
AGAIN EAST OF THE BLUE RIDGE LOOKS FEEBLE. THERE IS GOOD SUBSIDENCE
BEHIND THIS FEATURE BY 18Z TUESDAY BUT ANOTHER WAVE AND THE FRONT
ITSELF WILL EDGE CLOSER TOWARD TUE EVENING...WHICH WILL BRING A
BETTER THREAT OF SHOWERS AND STORMS TO THE MOUNTAINS WITH ISOLATED
TO WIDELY SCATTERED COVERAGE OVER THE FOOTHILLS AND PIEDMONT.
TUESDAY WILL BE HOT...WITH ENOUGH SUN TO SEND TEMPS INTO THE LOWER
TO MID 90S EAST...AND LOWER TO MID 80S WEST.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
AS OF 224 PM EDT MONDAY...
A WEAK COLD FRONT SLIDES ACROSS THE REGION TUESDAY NIGHT...PUSHING
PRECIPITATION TO THE EAST COAST. HIGH PRESSURE BUILDS IN FROM THE
WEST THROUGH WEDNESDAY. THE ASSOCIATED DEW POINT FRONT AND DRIER AIR
IS LAGGING WAY BEHIND AND DOES NOT ENTER THE FORECAST AREA UNTIL
LATE WEDNESDAY MORNING. THIS DEW POINT FRONT MAY MAKE IT AS FAR AS
THE VA/NC BORDER WEDNESDAY AFTERNOON...THEN BEGINS TO RETREAT TO THE
NORTH WEDNESDAY NIGHT AND THURSDAY. SURFACE HIGH PRESSURE WILL KEEP
MOST OF THE AREA DRY BUT COULD SEE ISOLATED DIURNAL SHOWERS SOUTH OF
THE DEW POINT FRONT WEDNESDAY AFTERNOON/EVENING. AS THIS SURFACE
RIDGE DRIFTS OFF THE MID ATLANTIC COAST THURSDAY...SOUTHEAST FLOW
AND ATLANTIC MOISTURE WILL INCREASE THE CHANCE FOR SHOWERS FOR AREAS
ALONG AND EAST OF THE BLUE RIDGE...ESPECIALLY THE NORTH CAROLINA
HIGH COUNTY THURSDAY AFTERNOON. EVEN THOUGH FLOW IS WEAK
ALOFT...WARM SOUTHWEST FLOW WILL OVERRUN THIS RIDGE/INSITU WEDGE TO
PRODUCE A LOW STRATUS DECK AND A CHANCE FOR LIGHT RAIN/DRIZZLE FOR
AREAS EAST OF THE BLUE RIDGE OVERNIGHT THURSDAY.
TEMPERATURES WILL RANGE FROM THE UPPER 70S TO LOWER 80S ACROSS THE
MOUNTAINS AND UPPER 80S TO LOWER 90S EAST WEDNESDAY AFTERNOON.
EASTERLY FLOW THURSDAY WILL PRODUCE UNIFORM TEMPERATURES IN THE 80S.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 248 PM EDT MONDAY...
HIGH PRESSURE EXITS THE MID ATLANTIC COAST ON FRIDAY AND WILL BE
REPLACED BY A LEE TROUGH. WITH AN UPPER LEVEL RIDGE ACROSS THE GULF
STATE TO THE SOUTHEAST COAST...NEARLY ZONAL FLOW MAY BRING A SHORT
WAVE OVER THE REGION FRIDAY. THIS SHORT WAVE WILL HELP SPARK
CONVECTION THROUGH THE AFTERNOON AND EVENING HOURS. IF THIS SHORT
WAVE DOES NOT MATERIALIZE...DIURNAL CONVECTION IS STILL POSSIBLE
WITH ABUNDANT MOISTURE...AFTERNOON HEATING AND A LEE TROUGH. FOR THE
WEEKEND...A COLD FRONT IS EXPECTED TO PASS OVER THE REGION SATURDAY
(GFS) OR SUNDAY (ECM). WITH A STUBBORN UPPER LEVEL RIDGE TO THE
SOUTH...FAVORING THE SLOWER ECM RUN. PREFRONTAL OR DIURNAL
CONVECTION IS POSSIBLE SATURDAY BUT WILL KEEP THE HIGHEST POPS WITH
THE FRONTAL PASSAGE SUNDAY. NOT QUITE SURE IF THE FRONT WILL
COMPLETE CLEAR THE FORECAST AREA AS THE UPPER LEVEL RIDGE CONTINUES
TO HANG ACROSS THE SOUTHERN STATES.
TEMPERATURES WILL REMAIN WARMER THAN NORMAL UNTIL THE FRONT CLEARS
THE AREA. ONCE THE FRONT PASSES...TEMPERATURES WILL RUN COOLER THAN
NORMAL WITH HIGHS IN THE 70S.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 140 AM EDT TUESDAY...
OVERALL VFR SHOULD PREVAIL THIS MORNING AT THE TAF LOCATIONS. A
FEW SHOWERS MAY MAKE A RUN AT KLWB OVER THE NEXT COUPLE OF HOURS
BUT LIKELY TO DISSIPATE CROSSING THE RIDGES SO LEAVING OUT
MENTION. WELL MIXED LOW LEVELS WILL LIKELY INHIBIT MUCH FOG
DEVELOPMENT THIS MORNING. CANT TOTALLY RULE OUT SOME BRIEF VALLEY
FOG AT KLWB/KBCB ALTHOUGH FORECAST FOG STABILITY VALUES SHOW ONLY
SPOTTY COVERAGE AT BEST.
UPPER TROUGH AND ITS ASSOCIATED COLD FRONT WILL APPROACH FROM THE
NORTHWEST THIS AFTERNOON WITH MOSTLY ISOLATED MOUNTAIN
SHOWERS/STORMS EXPECTED DURING THE DAY AHEAD OF THE BOUNDARY.
HOWEVER MAY SEE A MORE ORGANIZED BAND DROP IN FROM THE NW WITH THE
LEADING PRE- FRONTAL CONVERGENCE...SO INCLUDING A VCTS MENTION
ACROSS THE SOUTHEAST WEST VA SITES AROUND MID AFTERNOON AND LATE
AT KBCB. OTRW EXPECTING MOSTLY VFR AFTER EARLY MID DECK ERODES AND
SCATTERED- BROKEN CU FIELDS BETWEEN 4-6K FT TAKE SHAPE WITH
HEATING. WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
THIS EVENING INTO TONIGHT.
MEDIUM TO HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS
DURING THE PERIOD.
EXTENDED AVIATION DISCUSSION...
FRONT SETTLES CLOSER TUESDAY NIGHT INTO WEDNESDAY...WHEN BETTER
COVERAGE OF SHRA/TSRA IS EXPECTED. HOWEVER LOW CONFIDENCE ON THE
TIMING AND SOUTHWARD POSITION OF THE BOUNDARY ON WEDNESDAY AT THIS
POINT PENDING PRE-FRONTAL COVERAGE FROM TUESDAY NIGHT. FOR NOW APPEARS
MAINLY VFR OUTSIDE OF EARLY MORNING FOG WEDNESDAY...THEN PERIODS
OF MVFR WEDNESDAY AFTERNOON ESPECIALLY SOUTHERN SECTIONS...AND
MAINLY ACROSS THE SOUTH/SOUTHWEST THURSDAY AFTERNOON FOR MORE
ISOLATED NATURE COVERAGE. FRONT WASHES OUT TO THE SOUTH OF THE
AREA FRIDAY WITH MORE WIDELY SCATTERED DIURNAL NATURE SHOWERS AND
STORMS...THEN PERHAPS BECOMING MORE WIDESPREAD SATURDAY WITH
PERIODIC MVFR IN MORE ORGANIZED COVERAGE AHEAD OF ANOTHER COLD
FRONT ARRIVING FROM THE NORTHWEST LATE. OTRW WILL SEE A DAILY
TREND OF EARLY MVFR/IFR IN FOG...FOLLOWED BY BRIEF VFR...THEN
INCREASING AFTERNOON/EVENING CONVECTION WHEN MVFR TO LOCAL IFR
WILL BE POSSIBLE.
&&
.EQUIPMENT...
AS OF 730 AM EDT FRIDAY ...
THE VISIBILITY SENSOR AT KDAN...DANVILLE REGIONAL AIRPORT...WILL
BE OUT OF SERVICE UNTIL FURTHER NOTICE. A PART HAS BEEN BACK-ORDERED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/WP
NEAR TERM...JH/WP
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...JH/KK
EQUIPMENT...RAB
AREA FORECAST DISCUSSION
NWS ALBANY NY
843 AM EDT TUE SEP 2 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL SUPPLY THE REGION WITH ANOTHER DAY OF A
SOUTHWEST FLOW WHICH WILL BRING VERY WARM TEMPERATURES ONCE MORE. A
COLD FRONT WILL APPROACH THE REGION LATE TODAY INTO THE EVENING
BRINGING SHOWERS AND THUNDERSTORMS...SOME OF WHICH COULD CONTAIN
HEAVY RAINFALL AND GUSTY WINDS. SLIGHTLY COOLER AND NOTICEABLY DRIER
AIR WILL FOLLOW ON WEDNESDAY. THE DRY WEATHER IS EXPECTED TO
CONTINUE THE REST OF THE WORK WEEK WITH WARMING TEMPERATURES ONCE
MORE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 841 AM EDT...QUICK UPDATE TO ACCOUNT FOR ISOLD SHOWERS AHEAD
OF A WEAK SFC TROUGH IN THE WARM SECTOR. SOME SHOWERS ARE ACROSS
THE MOHAWK VALLEY...AND MOVED THROUGH THE CAPITAL REGION...AND THE
BERKSHIRES AND SRN VT. THESE SHOWERS WITH PERHAPS A RUMBLE OF
THUNDER WILL LIMIT THE HEATING THIS MORNING. THE BETTER FORCING
FOR SOME STRONGER THUNDERSTORMS AHEAD OF THE COLD FRONT LOOK LIKE
THEY WILL NOT REACH THE WRN PERIPHERY OF THE FCST AREA UNTIL 22Z-
00Z BASED ON THE LATEST HRRR GUIDANCE. THE FOG WAS ALSO REMOVED
FROM THE GRIDS...AND THE CLOUD COVER WAS INCREASED OVER THE NRN
AND CNTRL THIRD.
THE H500 TEMP THIS MORNING IS -6C WITH KBUF -8C. THE 12Z KALB RAOB
INDICATES A STRONG LOW TO MID LEVEL CAP IS BETWEEN 750-650 HPA
WHICH WILL CURTAIL ANY STRONG TO POSSIBLY SEVERE THREAT UNTIL THE
LATE PM/EARLY EVENING.
OTHERWISE IT WILL BECOME RATHER HOT AGAIN ONCE MORE AS TEMPERATURES
CREST WELL INTO THE 80S. IN THE MID HUDSON VALLEY AND LOWER
LITCHFIELD COUNTY AMBIENT TEMPERATURES COULD TOUCH 90. COMBINE THAT
WITH DEWPOINTS AROUND 70...AND THE APPARENT TEMPERATURES WILL REACH
THE MID AND UPPER 90S...SHORT OF ADVISORY CRITERIA. HILLTOWNS
WILL HAVE APPARENT TEMPERATURES GENERALLY IN THE 85-90 RANGE.
A SOUTH TO SOUTHWEST WIND WILL AVERAGE 5 TO 15 MPH.
A COLD FRONT...CURRENTLY WORKING THROUGH THE OHIO VALLEY...IS
FORECAST TO CROSS OUR REGION LATE THIS AFTERNOON TO THE NORTH AND
WEST OF ALBANY...AND DURING THE EARLY EVENING ALBANY SOUTH AND
EAST.
THE ENTRANCE OF A POTENT UPPER LEVEL JET (NEAR 100 KTS) LOOKS TO
MOVE ACROSS THE REGION THIS EVENING. THE BEST FORCING STILL LOOKS TO
LIFT NORTHWEST OF OUR REGION BUT IT LOOKS CLOSER THAN THIS TIME
YESTERDAY.
THIS JET WILL INCREASE THE DEEP LAYER WIND SHEAR. COMBINE THAT WITH
PRETTY GOOD INSTABILITY (SBCAPES AVERAGING AROUND 1500 J/KG)...AND
IT IS A GOOD BET SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
AFTERNOON TO OUR WEST AND MOVE NORTHWEST TO SOUTHEAST.
MITIGATING FACTORS INCLUDE A MODEST MID LEVEL LAPSE RATES...ONLY
AROUND 5.5 C/KM. ALSO...THE CAP THAT WAS DISCUSSED EARLY MIGHT
PERSIST INTO THIS EVENING...WHICH COULD CONTINUE TO HINDER
CONVECTION...ALTHOUGH IT IS RATHER WEAK.
IF THUNDERSTORMS DO GET GOING...THEY WILL HAVE A HEALTHY WIND FIELD
TO WORK WITH...WHICH COULD ALLOW FOR BOWING SEGMENTS AND PERHAPS A
SQUALL LINE TO DEVELOP. THESE COULD PRODUCE STRONG TO DAMAGING WIND
GUSTS. SPC CONTINUES TO ONLY HIGHLIGHT THE SOUTHWESTERN PORTION OF
THE MOHAWK VALLEY IN "SLIGHT RISK" FOR SEVERE THUNDERSTORMS. HOWEVER
WE WILL CONTINUE TO USE POSSIBLE GUSTY WINDS AND HEAVY RAINFALL
EVERYWHERE ACROSS OUR REGION.
BY FAR...THE BIGGEST THREAT TODAY WOULD BE DAMAGING WIND...AND WITH
ONLY A VERY SMALL CHANCE FOR LARGE HAIL IN THE BIGGEST UPDRAFTS.
THUNDERSTORM ACTIVITY WILL PERSIST INTO THE EVENING HOURS...BUT AS
THE COLD FRONT MOVES BY...LINGERING SHOWERS AND WEAKENING
THUNDERSTORMS SHOULD DISSIPATE BY AROUND MIDNIGHT.
A SLIGHTLY COOLER AND DRIER AIR MASS WILL MOVE IN
OVERNIGHT...LOWERING TEMPERATURES FROM THE MID 50S NORTHWEST OF THE
CAPITAL REGION...TO THE LOWER TO MID 60S ALBANY SOUTHWARD.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
WEDNESDAY WILL FEATURE A GOOD DEAL OF SUNSHINE...A NORTHWEST BREEZE
10-15 MPH AND HIGH TEMPERATURES 80-85 IN THE VALLEYS (WARMEST NEAR
POUGHKEEPSIE) MID TO UPPER 70S OVER THE HIGHER TERRAIN. DEWPOINTS
WILL DROP INTO THE 50S.
WEDNESDAY NIGHT AS HIGH PRESSURE MOVES OVERHEAD...AND THE SKY IS
EXPECTED TO CLEAR...TEMPERATURES WILL DIP INTO THE 50S REGION WIDE
WITH MID TO UPPER 40S ACROSS THE ADIRONDACKS AND PORTIONS OF THE
SOUTHERN GREENS. IT LOOKS AS IF SOME PATCHY FOG SHOULD FORM
OVERNIGHT.
THURSDAY...HIGH PRESSURE WILL BEGIN TO DRIFT OFFSHORE...ALLOWING A
SOUTHERLY FLOW TO BEGIN TO PUMP WARMER AND SLIGHTLY MORE HUMID AIR
BACK INTO THE REGION. HIGHS WILL REACH AROUND 80 OVER THE HIGHER
TERRAIN...CLOSER TO 85 IN THE VALLEYS. DEWPOINTS WILL BE AROUND
60.
THURSDAY NIGHT WILL BE MILD WITH LOWS RANGING FROM THE UPPER 50S IN
OUTLYING AREAS...60S MOST OTHER PLACES...LOCALLY UPPER 60S IN THE
CAPITAL REGION.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE LARGE AND WARM HIGH PRESSURE SYSTEM WILL HOLD OVER THE REGION
FOR MOST OF FRIDAY WITH SLOWLY INCREASING CLOUDS EXPECTED AND HIGHS
IN THE 80S AS 850 MB TEMPS REACH +16 TO +18 DEG CELSIUS. LATE IN THE
DAY THERE IS A CHANCE OF SHOWERS OR TSTMS ACROSS THE NORTHWEST PART
OF THE FORECAST AREA AS A COLD FRONT AND UPPER LEVEL TROF APPROACH
FROM THE WEST.
FRI NIGHT INTO SATURDAY...MOST ACTIVE PORTION OF THE LONG TERM WITH
A COLD FRONT INTERACTING WITH A MOIST AND UNSTABLE AIR MASS. MODEL
TIMING OF THE BOUNDARY IS STILL VARIABLE...BUT THE MODELS ARE CLOSER
THAN THEY WERE 24 HOURS AGO. ALL THE MEDIUM RANGE MODELS NOW AGREE
THAT ANY SHOWERS ASSOCIATED WITH THIS FRONTAL BOUNDARY WILL BE OUT
OF THE REGION BEFORE SUNDAY...WITH SOME MODELS MUCH SOONER. WILL
CONTINUE TO KEEP CHANCE POPS ACROSS THE REGION FRIDAY NIGHT AND
SATURDAY...THEN LOWER POPS TO ONLY SLIGHT CHANCE BY LATE SATURDAY
NIGHT. LOWS FRIDAY NIGHT WILL BE IN THE UPPER 50S AND 60S. HIGHS
SATURDAY IN THE UPPER 60S ACROSS THE ADIRONDACKS...AND THE 70S TO
LOWER 80S ELSEWHERE. LOWS SATURDAY NIGHT IN THE UPPER 40S AND 50S AS
THE COOLER AIR BEHIND THE FRONT BEGINS TO SEEP IN.
ON SUNDAY A SPRAWLING HIGH PRESSURE SYSTEM WILL BUILD INTO THE
REGION AND CONTROL OUR WEATHER INTO EARLY NEXT WEEK. THIS HIGH
PRESSURE AREA IS OF CANADIAN ORIGIN SO IT WILL BE NOTICEABLY COOLER
SUNDAY AND MONDAY. HIGHS SUNDAY AND MONDAY WILL BE IN THE MID 60S TO
MID 70S. LOWS SUNDAY NIGHT IN THE MID 40S TO MID 50S.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
ANY LEFTOVER FOG/STRATUS AT KGFL/KPSF WILL BE GONE BY 13Z...
OTHERWISE THE TAF SITES WILL FEATURE VFR CONDITIONS UNTIL A
SHORTWAVE TROF AND COLD FRONT APPROACH FROM THE WEST LATE IN THE DAY
AND MOVE THROUGH THE TAF SITES THIS EVENING. SOME ISOLD SHOWERS
ASSOCIATED WITH A PREFRONTAL SFC TROUGH MAY GET CLOSE TO
TERMINALS...AND A VCSH GROUP WAS USED AT KALB BTWN 12Z-16Z.
BEGINNING 21Z TO 23Z HAVE FORECASTED A 4-6 HOUR WINDOW OF PROB30 FOR
MVFR CONDITIONS DUE TO THUNDERSTORMS AT ALL THE TAF SITES. THE
THREAT FOR TSTMS WILL END WHEN THE COLD FRONT MOVES THROUGH
BETWEEN 02Z AND 04Z TUESDAY NIGHT.
SURFACE WINDS WILL BECOME SOUTH OR SOUTHWEST AT 5 TO 10 KTS TODAY
INTO THIS EVENING...THEN SHIFT TO WESTERLY BEHIND THE COLD FRONT AT
4 TO 8 KTS.
OUTLOOK...
WEDNESDAY TO FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT TO SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...TSRA.
&&
.FIRE WEATHER...
HIGH PRESSURE WILL MOVE EAST OF OUR REGION TODAY ALLOWING A COLD
FRONT TO MOVE IN LATE TODAY INTO THIS EVENING. THIS FRONT WILL BRING
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS TO THE AREA...MAINLY LATE
THIS AFTERNOON INTO THE EARLY EVENING HOURS.
IT WILL BE A RATHER HOT DAY WITH PARTIAL SUNSHINE BEFORE THE SHOWERS
AND STORMS ARRIVE. RH VALUES WILL ONLY DROP TO THE 55-65 PERCENT
RANGE THIS AFTERNOON. A SOUTH TO SOUTHWEST WIND WILL AVERAGE 5-15
MPH.
RAINFALL FROM THE THUNDERSTORMS LOOK REACH AROUND A QUARTER INCH OR
BETTER IN MOST AREAS FROM ALBANY NORTHWARD...A QUARTER INCH OR LESS
SOUTH OF ALBANY. HOWEVER...ANY THUNDERSTORM COULD PRODUCE HEAVY
RAINFALL PRODUCING LOCALIZED AMOUNTS EASILY EXCEEDING AN INCH IN ANY
GIVEN SPOT.
RH VALUES TONIGHT WILL BE IN THE TYPICAL 80-100 PERCENT RANGE
ALTHOUGH A BIT OF BREEZE MIGHT PERSIST IN MANY AREAS...AS THE WIND
SHIFTS FROM SOUTHWEST TO NORTHWEST.
WEDNESDAY WILL FEATURE LOWER HUMIDITY ALONG WITH A GOOD DEAL OF
SUNSHINE. A NORTHWEST BREEZE WILL AVERAGE 10-15 MPH WITH SOME HIGHER
GUSTS INTO THE 20S...MAINLY OVER THE HIGHER TERRAIN/MOHAWK VALLEY
AND GREATER CAPITAL REGION. AFTERNOON RH VALUES WILL DROP INTO THE
35-45 PERCENT RANGE.
A FULL RECOVERY WEDNESDAY NIGHT WITH THE WIND GOING CALM...AND RH
VALUES NEAR 100 PERCENT WITH PLENTY OF DEW EXPECTED.
THE NEXT CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE LATE FRIDAY
INTO SATURDAY.
&&
.HYDROLOGY...
IT WILL BE MAINLY DRY THROUGH MIDDAY. THEN...SHOWER AND THUNDERSTORM
COVERAGE SHOULD INCREASE FROM NORTHWEST TO SOUTHEAST THROUGH THE
AFTERNOON INTO THE EARLY EVENING. AVERAGE BASIN RAINFALL WITH THESE
STORMS IS PROJECTED TO BE AROUND HALF AN INCH ACROSS NORTHERN AREAS
OF OUR HYDROLOGICAL SERVICE AREA (HSA)...NORTH OF ALBANY. LOOK FOR
AROUND HALF AN INCH IN AND AROUND THE CAPITAL REGION...AND LESSER
AMOUNTS OF A QUARTER INCH OR LESS FURTHER SOUTH.
PWATS ARE EXPECTED TO EXCEED TWO INCHES TODAY. THIS WILL ALLOW FOR
THE POTENTIAL FOR ANY THUNDERSTORM TO PRODUCE LOCALLY MUCH HEAVY
RAINFALL...POSSIBLY EXCEEDING AN INCH AND THIS RAIN COULD FALL IN A
SHORT TIME. THEREFORE THERE IS THE POTENTIAL FOR SIGNIFICANT PONDING
OF WATER ON ROADWAYS AND AREAS OF POOR DRAINAGE. WHILE THE THREAT
FOR ANY ORGANIZED FLASH FLOODING IS VERY LOW...A HIGH LOCALIZED
FLASH FLOOD CANNOT BE RULED OUT.
DRIER WEATHER RETURNS BY WEDNESDAY...LASTING THROUGH THE REMAINDER
OF THE WORKWEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/WASULA
NEAR TERM...HWJIV/WASULA
SHORT TERM...HWJIV
LONG TERM...GJM
AVIATION...GJM/WASULA
FIRE WEATHER...HWJIV/NAS
HYDROLOGY...HWJIV/NAS
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1130 AM EDT TUE SEP 2 2014
.UPDATE (REST OF TODAY AND TONIGHT)...
15Z WATER VAPOR AND H4 RAP ANALYSIS SHOW THE MAIN NORTHERN STREAM
FLOW FAR TO OUR NORTH ALONG THE CANADIAN BORDER AND OVER TOP AN
ELONGATED WEST TO EAST ORIENTED UPPER RIDGE EXTENDING ACROSS THE
SOUTHERN TIER OF THE CONUS. OUR FORECAST AREA RESIDES UNDER THIS
LARGE UPPER RIDGE...HOWEVER A TUTT FEATURE RETROGRADING WESTWARD
OVER THE BAHAMAS IS BEGINNING TO ERODE THE RIDGE TO OUR SOUTH
AND EAST...AND WILL BEGIN TO BREAK DOWN THE RIDGE OVER OUR HEADS
TONIGHT.
02/12Z SOUNDING PROFILE SHOWS THE INFLUENCE OF THE UPPER RIDGE
OVERHEAD WITH A SUBSIDENCE INVERSION SIGNATURE AROUND 750MB. ABOVE
THIS LAYER IT ON THE DRY SIDE. THE RESULTING PW IS LOW AROUND
1.7"...WHICH IS BELOW AVERAGE FOR EARLY SEPTEMBER...BUT NOT AN
EXTREME VALUE. WE HAVE SEEN A BIT OF COOLING IN THE MID-LEVELS SINCE
MONDAY...POSSIBLY THE VERY BEGINNING INFLUENCE OF THE APPROACHING
TUTT. WILL EXPECT TO SEE ANOTHER DEGREE OR 2 OF COOLING IN THE
MID-LEVELS OVER THE NEXT 24 TO 36 HOURS AS THE TUTT PASSES JUST TO
OUR SOUTH. THIS COOLING ALONG WITH OUR EVENTUAL POSITION ON THE
EASTERN PERIPHERY OF THE TUTT (FAVORED FOR UPWARD MOTION AND
CONVECTION) MAY LEAD TO ENHANCED CONVECTION LATER IN THE WEEK.
BACK TO TODAY. SOME MIXED SIGNALS REGARDING CONVECTIVE TIMING AND
EVOLUTION FOR THE AFTERNOON AND EVENING. HIRES CONVECTION ALLOWING
MODELS ARE KIND OF SPLIT...WITH A FEW MEMBERS RATHER ACTIVE ALONG
THE I-75 CORRIDOR LATER TODAY...AND A FEW MEMBERS WHO HAVE TROUBLE
GENERATING MUCH CONVECTION...AND ESPECIALLY DEEP CONVECTION. MORE
THAN LIKELY IT IS DIFFERING WAYS THE GUIDANCE IS HANDLING THE
SUBSIDENCE OF THE UPPER RIDGE RESULTING IN THE DIFFERENCES. AM
TENDING TO SIDE ON THE MORE ACTIVE CONVECTION SOLUTIONS. THE
SUBSIDENCE INVERSION IS THERE...BUT IS NOT REALLY PRONOUNCED. GIVEN
THE WEAKNESS OF THE OVERALL SUBSIDENCE AND THE EASTERLY FLOW BEING
FAVORED FOR ENHANCED CONVERGENCE/UPDRAFTS ALONG THE FLORIDA WEST
COAST WILL KEEP HIGH END CHANCE POPS IN THE FORECAST ALONG THE
ENTIRE I-75 CORRIDOR. SIMILAR TO THE PAST FEW DAYS...THE STORMS ARE
LIKELY TO BREAK OUT FIRST DURING THE EARLY/MID AFTERNOON DOWN TOWARD
FORT MYERS AND OVER THE INTERIOR SOUTH (HIGHLANDS/DESOTO/HARDEE
COUNTIES)...AND THEN MIGRATE/EVOLVE NORTH AND WEST INTO THE TAMPA
BAY AREA AND NATURE COAST DURING THE LATE AFTERNOON/EARLY EVENING.
THE EASTERLY FLOW JUST ABOVE THE SURFACE IS 8-10 KNOTS THIS
AFTERNOON WHICH WILL SLOW THE INLAND PROPAGATION OF THE
SEA-BREEZE...BUT NOT STOP IT. THEREFORE...WOULD EXPECT THE BREEZE TO
BE SET UP NEAR OR JUST INSIDE OF I-75 BY LATE AFTERNOON...AND IT
WILL BE THIS ZONE WHERE STORMS WILL IGNITE AS THE EAST COAST
SEA-BREEZE ARRIVES AND INTERACTS.
STORM MOTION WILL BE WESTWARD AFTER INITIATION...SO MARINERS SHOULD
BE AWARE OF THE WEATHER OVER LAND TO THEIR EAST AND BE PREPARED FOR
STORMS TO RAPIDLY DEVELOP AND MOVE OFFSHORE LATER TODAY. THE
ACTIVITY WILL ALL PUSH OFFSHORE WITHIN A COUPLE HOURS OF SUNSET AND
PROVIDE THE REGION WITH A MOSTLY DRY AND SEASONABLE OVERNIGHT
PERIOD.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION LATE THIS MORNING.
BEGINNING TO SEE THE FIRST OF A CU FIELD BEGIN TO DEVELOP. SCT
SHOWERS AND STORMS WILL BE MOVING EAST TO WEST ACROSS THE PENINSULA
DURING THE AFTERNOON. KFMY/KRSW/KPGD WILL BE FIRST TO SEE THE STORMS
IN THE VICINITY BY MID AFTERNOON. FURTHER NORTH AROUND THE TAMPA BAY
TERMINALS STORMS ARE LIKELY TO BE LATER IN THE AFTERNOON AND EVENING
HOURS. AWAY FROM ANY STORMS...VFR CONDITIONS WILL PREVAIL THROUGH
THE TAF PERIOD.
&&
.MARINE...
EAST SOUTHEAST WINDS LESS THAN 15 KNOTS AND SEAS 2 FEET OF LESS
WILL CONTINUE INTO NEXT WEEK AS HIGH PRESSURE OVER THE ATLANTIC
RIDGES WEST OVER THE FLORIDA PENINSULA. THE SEA BREEZE WILL SET UP
ALONG THE COASTLINE EACH DAY TURNING THE WINDS TO AN ONSHORE FLOW
OUT OF THE SOUTHWEST THROUGH NORTHWEST DIRECTION. SCATTERED SHOWERS
AND STORMS WILL BE POSSIBLE EACH DAY DEVELOPING OVER LAND AND THEN
PUSHING WESTWARD OVER THE COASTAL WATERS DURING THE EVENING HOURS.
THE ONLY EXPECTED HAZARD WILL BE GUSTY WINDS AND HIGHER SEAS IN THE
VICINITY OF THUNDERSTORMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 91 76 91 76 / 50 30 40 30
FMY 93 74 91 74 / 50 10 50 20
GIF 93 74 92 74 / 40 10 40 10
SRQ 92 75 91 73 / 50 30 50 30
BKV 93 72 93 71 / 50 20 40 30
SPG 92 79 90 78 / 50 30 40 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...MROCZKA
MARINE...WYNN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
639 AM CDT TUE SEP 2 2014
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 357 AM CDT TUE SEP 2 2014
AS OF 0845 UTC, STRONG THUNDERSTORMS WERE UNDERWAY ACROSS
COMANCHE, BARBER, AND CLARK COUNTY, TIED MOST CLOSELY TO A ZONE
OF FRONTOGENESIS AT AROUND 750MB STRETCHING FROM THE OKLAHOMA
PANHANDLE EAST- NORTHEASTWARD TO FAR SOUTH-CENTRAL KANSAS. THE
HIRES CONVECTIVE- ALLOWING MODELS PICKED UP ON THIS QUITE WELL IN
THE COMPOSITE REFLECTIVITY AND QPF FIELDS. THESE MODELS SHOW THE
CONVECTION MOVING OFF INTO NORTHERN OKLAHOMA BEFORE 1200 UTC, SO
WE WILL TAPER THE POPS DOWN AROUND THIS TIME. EARLIER IN THE
SHIFT, WE ADDED SOME AREAS OF 1/2SM FOG GENERALLY ALONG/SOUTH OF
THE ARKANSAS RIVER IN A ZONE OF SATURATED SURFACE AIR NORTH OF THE
WEAK SURFACE LOW. ANY FOG WHICH DEVELOPS SHOULD ERODE NOT TOO LONG
AFTER SUNRISE, HOWEVER LOW STRATUS IS EXPECTED TO HOLD ON THROUGH
LATE MORNING NORTH OF THE 850MB LOW. THIS MAY THROW A BIT OF A
CURVE BALL IN THE TEMPERATURES TODAY, SO WE ADJUSTED THEM DOWN
(USING A MODIFIED HRRR SOLUTION) OUT ACROSS THE WESTERN HALF FOR
THE FIRST HALF OF THE DAY WITH CLOUDS KEEPING A LID IN THE WARM-
UP. ONCE THE CLOUDS ERODE COMPLETELY BY MIDDAY/EARLY AFTERNOON,
TEMPERATURES WILL WARM INTO THE MID 80S. ANY SURFACE-BASED
CONVECTION LATE THIS AFTERNOON WILL BE DOWN ALONG THE SURFACE
FRONT ACROSS NORTHWEST OKLAHOMA. BY EARLY EVENING, SOME OF THE
THUNDERSTORM ACTIVITY MAY HEAD UP INTO BARBER COUNTY AND EXPAND IN
COVERAGE SOME AS LOW LEVEL JET STRENGTHENS AFTER SUNSET. RICH LOW
LEVEL MOISTURE LEADING TO 2000-3000 J/KG MOST-UNSTABLE CAPE WILL
SUPPORT RENEWED SEVERE WEATHER RISK, EVEN WITH ELEVATED STORMS
DURING THE LATE NIGHT HOURS TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM CDT TUE SEP 2 2014
THE LONGWAVE SYNOPTIC FLOW PATTERN WILL BE SOMEWHAT PROGRESSIVE
THROUGH THIS FORECAST, AT LEAST ENOUGH TO BRING SIGNIFICANT SENSIBLE
WEATHER CHANGES TO THE AREA FOR LATE IN THE WEEK. WEDNESDAY AND
THURSDAY WILL SEE SUNNY AND VERY WARM TO HOT TEMPERATURES, AS THE
UPPER JET LIFTS NORTHWARD ACROSS THE NORTHERN TIER OF STATES
ALLOWING THE LARGE SOUTHERN ROCKIES/SOUTHERN PLAINS HIGH PROVIDE
STRONG SUBSIDENCE, FULL INSOLATION AND SOUTHERLY SURFACE WINDS.
THE ECMWF/GFS AND NAM ARE IN EXCELLENT AGREEMENT IN BREAKING DOWN
THIS PATTERN BY THURSDAY AND BRINGING A COLD FRONT THROUGH THE
NORTHERN PLAINS OF WESTERN NEBRASKA AND AS FAR SOUTH AS WEST
CENTRAL KANSAS WITH THE LEADING COOLER AIR SURGE BY THURSDAY
AFTERNOON. CONVECTION COULD OCCUR LATE THURSDAY AFTERNOON OR
EVENING AS WELL WITH THIS COLD FRONT FEATURE, BUT UPPER
SUPPORT/DYNAMICS FOR WIDESPREAD STORM DEVELOPMENT IS LACKING. THE
UPPER JET WILL SINK SOUTHWARD THROUGH THE CENTRAL PLAINS AND
CENTRAL MISSISSIPPI VALLEY, DRIVING THE COLD FRONT FARTHER SOUTH
INTO THE SOUTHERN PLAINS BY SATURDAY MORNING. THE RESULT WILL BE
ADDITONAL CHANCES FOR POSSIBLY EVEN SEVERE STORMS, BUT PERHAPS
JUST POST SURFACE FRONTAL HIGH BASED CONVECTION FROM MID LEVEL
FRONTOGENESIS FRIDAY OR FRIDAY NIGHT WITH MUCH MORE PLEASANT
TEMPERATURES IN THE 70S.
A SLOW WARMING TREND IS LIKELY THROUGH THE LATE PART OF THE WEEKEND
INTO EARLY NEXT WEEK AS RETURN SOUTHERLY FLOW BECOMES REESTABLISHED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 637 AM CDT TUE SEP 2 2014
IFR FOG IS STILL POSSIBLE THROUGH AROUND 14 UTC BEFORE INSOLATION
BEGINS TO STRONGLY WARM THE BOUNDARY LAYER THROUGH THE CLOUD LAYER.
VISIBILITY HAS ALREADY FLUCTUATED AROUND 2 MILES AT GCK AND DDC
SINCE ABOUT 9 Z. THUNDERSTORMS SHOULD NO LONGER BE A THREAT TOT HE
TERMINALS THIS MORNING. LIGHT SOUTHEAST WINDS WILL PREVAIL THROUGH
THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 87 68 98 71 / 20 10 0 0
GCK 87 67 100 71 / 10 10 0 10
EHA 87 66 99 69 / 10 0 10 10
LBL 87 69 100 72 / 10 10 0 10
HYS 86 67 99 73 / 10 10 10 10
P28 90 72 98 74 / 40 30 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...RUSSELL
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS JACKSON KY
948 AM EDT TUE SEP 2 2014
.UPDATE...
ISSUED AT 948 AM EDT TUE SEP 2 2014
THE FORECAST FOR THIS AFTERNOON HAS BECOME COMPLICATED BY THE
REMNANTS OF AN MCS OVER THE OHIO VALLEY AND THE OUTFLOW BOUNDARY
WHICH IS CURRENTLY MOVING INTO THE BLUEGRASS. CURRENT THINKING IS
THAT THE OUTFLOW BOUNDARY WILL GENERALLY WEAKEN AS IT CONTINUES
MOVING TO THE SOUTHEAST. THIS SHOULD BE TEMPORARY AND WILL THEN BE
THE FOCUS OF DEVELOPMENT LATER IN THE AFTERNOON. SO PRETTY MUCH GOING
WITH TWO PRONGS. THE FIRST BEING REDEVELOPMENT WITH THE OUTFLOW
BOUNDARY AND THE SECOND BEING THE PREFRONTAL ACTIVITY. THE SEVERE
THREAT TODAY WILL BE EFFECTED BY HOW MUCH DEBRIS CLOUD IS ABLE TO
MOVE INTO THE AREA. THE LOW LEVEL INSTABILITY WILL BE EFFECTED BY
EFFECTED BY THE CLOUDS. THE LATEST NAM BUFFER HAS REALLY BACKED OFF
FROM YESTERDAY WITH HALF THE CAPE THAN WHAT WAS FORECAST YESTERDAY.
ALSO MISSING IS THE DRY AIR POCKETS ALOFT WHICH WOULD HAVE BEEN
HELPFUL FOR WET MICROBURSTS TO OCCUR. CAN NOT RULE OUT SEVERE
THUNDERSTORMS...HOWEVER THE CHANCES HAVE GONE DOWN. MOST LIKELY WILL
STILL SEE A COUPLE OF SEVERE STORMS WITH THIS SYSTEM. UPDATED THE
FORECAST TO REFLECT THE CURRENT CONDITIONS AND MODEL TRENDS.
UPDATE ISSUED AT 649 AM EDT TUE SEP 2 2014
NO SIGNIFICANT CHANGES MADE THIS MORNING. LINE OF SHOWERS AND STORMS
EXTENDS FROM CINCINNATI SOUTHWEST TO THE NORTHWEST SIDE OF
LOUISVILLE. THIS LINE CONTINUES TO SLOWLY WEAKEN AS IT MOVES EAST. IF
IT WERE TO HOLD TOGETHER...LOOKS LIKE IT MAY WORK INTO THE BLUEGRASS
COUNTIES AFTER 13Z. HOWEVER...GIVEN THE TREND THIS SEEMS UNLIKELY AND
AT BEST PERHAPS AN ISOLATED SHOWER CAN HOLD TOGETHER. MAIN CONCERN
CONTINUES TO BE LATER TODAY...PRIMARILY AFTER 2 PM AS OUTFLOW FROM
THIS MORNINGS CONVECTION REDEVELOPS SHOWERS AND STORMS. NOT SURE THE
COVERAGE WILL BE ALL THAT GREAT AFTER LOOKING AT THE LATEST HRRR AND
NEW 06Z MAV GUIDANCE. BOTH OF THESE MODELS HAVE BACKED OFF
SIGNIFICANTLY ON THE CHANCES OF RAIN TODAY. HOWEVER...GOING TO STAY
THE COURSE AS THE TROUGH IS STILL FAIRLY DEFINED AND OUTFLOW HAS
ALREADY DEFINED A BOUNDARY FOR NEW CONVECTION TO DEVELOP.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT TUE SEP 2 2014
PRESENTLY...A SHORTWAVE TROUGH IS PUSHING INTO THE OHIO RIVER VALLEY
REGION. AN MCS DEVELOPED YESTERDAY EVENING HEAD OF THIS TROUGH AND
IS NOW MARCHING EASTWARD INTO CENTRAL/SOUTHERN INDIANA...STRETCHING
BACK TO THE SOUTHWEST ACROSS SOUTHERN ILLINOIS. IR SATELLITE HAS
SHOWN SOME WARMING WITH THE CLOUD TOPS OVER THE PAST HOUR OR
TWO...INDICATING THAT THIS MCS MAY ALREADY BE ON THE DECLINE. IN
FACT...THE HRRR SUPPORTS THE IDEA OF A DYING MCS AS IT TRIES TO PUSH
INTO CENTRAL KENTUCKY TOWARDS DAYBREAK. CANNOT RULE OUT A FEW SHOWERS
PUSHING INTO THE BLUEGRASS SHORTLY AFTER 8 AM...BUT ANTICIPATE MORE
OF THE ACTION WITH THE SHORTWAVE TROUGH WILL COME LATER THIS
AFTERNOON AS WE GENERATE SOME INSTABILITY. WITH THIS IN MIND...PLAN
TO BACK OFF THE POPS THROUGH MIDDAY WITH JUST SOME ISOLATED SHOWERS
FOR AREAS NORTH OF I-64. OUTFLOW FROM THE DYING MCS WILL BE PUSHING
ACROSS EASTERN KENTUCKY EARLY THIS AFTERNOON...AND COULD KICK START
THE CONVECTION AS IT ENCOUNTERS SOME DECENT INSTABILITY. THE FORCING
ALOFT SHOULD ALLOW FOR FAIRLY GOOD SHOWER AND THUNDERSTORM COVERAGE
BY MID TO LATE AFTERNOON. WITH BULK SHEAR VALUES OF 30-40KTS THIS
AFTERNOON...A SEVERE THREAT WOULD EXIST AS THUNDERSTORMS COULD PUT
OUT SOME DAMAGING WIND GUSTS. THE SHEAR PROFILES WEAKEN BY MID
EVENING AND THE LOSS OF DAYTIME INSTABILITY SHOULD YIELD WEAKENING
STORMS AFTER 6 PM. HOWEVER...A FEW GUSTY WINDS MAY STILL BE POSSIBLE
THROUGH 8 OR 9 PM.
THE SHORTWAVE TROUGH WILL STALL A COLD FRONT ACROSS SOUTHERN
KENTUCKY BY LATE THIS EVENING. GIVEN THE PRESENCE OF THIS
BOUNDARY...AND PLENTY OF MOISTURE...IT MAY BE POSSIBLE TO SEE
ISOLATED SHOWERS THROUGH THE NIGHT ACROSS THE SOUTHERN HALF OF
KENTUCKY. THIS BOUNDARY WILL LINGER AROUND INTO WEDNESDAY AND WITH
INSTABILITY AGAIN RAMPING UP DURING THE AFTERNOON...WE COULD BE
LOOKING AT A FEW MORE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HOWEVER...BY WEDNESDAY...VERY LITTLE SHEAR IS
PRESENT...SO WE SHOULD SEE MORE ORDINARY THUNDERSTORMS WITH NO SEVERE
THREAT.
TEMPERATURES OVER THE NEXT 2 DAYS SHOULD BE FAIRLY SIMILAR TO WHAT WE
HAVE SEEN LATELY WITH HIGHS INTO THE LOW TO MID 80S. SAME CAN BE SAID
FOR LOWS TONIGHT WITH READINGS GENERALLY AROUND 70.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 418 AM EDT TUE SEP 2 2014
THE FRONTAL BOUNDARY REFERENCED IN THE SHORT TERM WILL BE DISSOLVING
EARLY IN THE LONG TERM PERIOD...BUT THERE SHOULD STILL BE DRY AIR IN
PLACE WEDNESDAY NIGHT...ESPECIALLY ALOFT. IF ANY CONVECTIVE PRECIP
CAN DEVELOP OFF OF LOW LEVEL MOISTURE ON WEDNESDAY AFTERNOON...IT
SHOULD DIE OUT BY NIGHT AS HEATING IS LOST AND SUPPORT ALOFT WILL
LIKELY BE LACKING.
DEEPER MOISTURE WILL MAKE A COMEBACK LATE IN THE WEEK AND MAY FUEL
A RESURGENCE OF SHOWERS AND THUNDERSTORMS...BUT A SUBTROPICAL RIDGE
ALOFT OVER THE SE CONUS WILL HELP TO KEEP COVERAGE LIMITED FOR A
WHILE. THE RIDGE WILL WEAKEN AND GET SUPPRESSED BY A BROAD TROUGH
DROPPING SE INTO THE NE CONUS DURING THE WEEKEND. THIS WILL ALLOW A
COLD FRONT TO MOVE INTO OUR REGION FROM THE NW. THE SCENARIO WILL
ALLOW AN INCREASE IN PRECIP COVERAGE...WITH A PEAK EXPECTED ON
SATURDAY. EVEN THOUGH THE FRONT SHOULD PASS BY SUNDAY...THE MODELS
STILL LEAVE SOME QUESTION AS TO HOW EFFECTIVE THE FRONT WILL BE AT
BRINGING IN A DRIER AIR MASS. HAVE HELD ONTO LOW POPS IN THE
AFTERNOON AND EVENING ON SUNDAY AND MONDAY...ESPECIALLY IN OUR SE
COUNTIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 649 AM EDT TUE SEP 2 2014
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES OVER THE NEXT 24
TO 36 HOURS. A COLD FRONT WILL DROP SOUTH INTO EASTERN KENTUCKY
TODAY AND COULD SPAWN SCATTERED TO NUMEROUS THUNDERSTORMS THIS
AFTERNOON. PLAN TO STICK WITH THE VCTS THIS AFTERNOON AS
TIMING...COVERAGE...AND UNCERTAINTY ARE TOO GREAT TO GO WITH A
THUNDERSTORM PREVAILING GROUP. ACTIVITY SHOULD WANE BY MID TO LATE
EVENING WITH A QUIET NIGHT EXPECTED TONIGHT. HOWEVER...AS SKIES CLEAR
AND CALM WINDS...WE SHOULD SET THE STAGE FOR BETTER FOG PRODUCTION
TONIGHT...ESPECIALLY IF WE GET ANY RAIN TODAY. THUS...WILL TAKE
AIRPORTS BELOW MINIMUMS LATE TONIGHT WITH THE FOG.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
649 AM EDT TUE SEP 2 2014
.UPDATE...
ISSUED AT 649 AM EDT TUE SEP 2 2014
NO SIGNIFICANT CHANGES MADE THIS MORNING. LINE OF SHOWERS AND STORMS
EXTENDS FROM CINCINNATI SOUTHWEST TO THE NORTHWEST SIDE OF
LOUISVILLE. THIS LINE CONTINUES TO SLOWLY WEAKEN AS IT MOVES EAST. IF
IT WERE TO HOLD TOGETHER...LOOKS LIKE IT MAY WORK INTO THE BLUEGRASS
COUNTIES AFTER 13Z. HOWEVER...GIVEN THE TREND THIS SEEMS UNLIKELY AND
AT BEST PERHAPS AN ISOLATED SHOWER CAN HOLD TOGETHER. MAIN CONCERN
CONTINUES TO BE LATER TODAY...PRIMARILY AFTER 2 PM AS OUTFLOW FROM
THIS MORNINGS CONVECTION REDEVELOPS SHOWERS AND STORMS. NOT SURE THE
COVERAGE WILL BE ALL THAT GREAT AFTER LOOKING AT THE LATEST HRRR AND
NEW 06Z MAV GUIDANCE. BOTH OF THESE MODELS HAVE BACKED OFF
SIGNIFICANTLY ON THE CHANCES OF RAIN TODAY. HOWEVER...GOING TO STAY
THE COURSE AS THE TROUGH IS STILL FAIRLY DEFINED AND OUTFLOW HAS
ALREADY DEFINED A BOUNDARY FOR NEW CONVECTION TO DEVELOP.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT TUE SEP 2 2014
PRESENTLY...A SHORTWAVE TROUGH IS PUSHING INTO THE OHIO RIVER VALLEY
REGION. AN MCS DEVELOPED YESTERDAY EVENING HEAD OF THIS TROUGH AND
IS NOW MARCHING EASTWARD INTO CENTRAL/SOUTHERN INDIANA...STRETCHING
BACK TO THE SOUTHWEST ACROSS SOUTHERN ILLINOIS. IR SATELLITE HAS
SHOWN SOME WARMING WITH THE CLOUD TOPS OVER THE PAST HOUR OR
TWO...INDICATING THAT THIS MCS MAY ALREADY BE ON THE DECLINE. IN
FACT...THE HRRR SUPPORTS THE IDEA OF A DYING MCS AS IT TRIES TO PUSH
INTO CENTRAL KENTUCKY TOWARDS DAYBREAK. CANNOT RULE OUT A FEW SHOWERS
PUSHING INTO THE BLUEGRASS SHORTLY AFTER 8 AM...BUT ANTICIPATE MORE
OF THE ACTION WITH THE SHORTWAVE TROUGH WILL COME LATER THIS
AFTERNOON AS WE GENERATE SOME INSTABILITY. WITH THIS IN MIND...PLAN
TO BACK OFF THE POPS THROUGH MIDDAY WITH JUST SOME ISOLATED SHOWERS
FOR AREAS NORTH OF I-64. OUTFLOW FROM THE DYING MCS WILL BE PUSHING
ACROSS EASTERN KENTUCKY EARLY THIS AFTERNOON...AND COULD KICK START
THE CONVECTION AS IT ENCOUNTERS SOME DECENT INSTABILITY. THE FORCING
ALOFT SHOULD ALLOW FOR FAIRLY GOOD SHOWER AND THUNDERSTORM COVERAGE
BY MID TO LATE AFTERNOON. WITH BULK SHEAR VALUES OF 30-40KTS THIS
AFTERNOON...A SEVERE THREAT WOULD EXIST AS THUNDERSTORMS COULD PUT
OUT SOME DAMAGING WIND GUSTS. THE SHEAR PROFILES WEAKEN BY MID
EVENING AND THE LOSS OF DAYTIME INSTABILITY SHOULD YIELD WEAKENING
STORMS AFTER 6 PM. HOWEVER...A FEW GUSTY WINDS MAY STILL BE POSSIBLE
THROUGH 8 OR 9 PM.
THE SHORTWAVE TROUGH WILL STALL A COLD FRONT ACROSS SOUTHERN
KENTUCKY BY LATE THIS EVENING. GIVEN THE PRESENCE OF THIS
BOUNDARY...AND PLENTY OF MOISTURE...IT MAY BE POSSIBLE TO SEE
ISOLATED SHOWERS THROUGH THE NIGHT ACROSS THE SOUTHERN HALF OF
KENTUCKY. THIS BOUNDARY WILL LINGER AROUND INTO WEDNESDAY AND WITH
INSTABILITY AGAIN RAMPING UP DURING THE AFTERNOON...WE COULD BE
LOOKING AT A FEW MORE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HOWEVER...BY WEDNESDAY...VERY LITTLE SHEAR IS
PRESENT...SO WE SHOULD SEE MORE ORDINARY THUNDERSTORMS WITH NO SEVERE
THREAT.
TEMPERATURES OVER THE NEXT 2 DAYS SHOULD BE FAIRLY SIMILAR TO WHAT WE
HAVE SEEN LATELY WITH HIGHS INTO THE LOW TO MID 80S. SAME CAN BE SAID
FOR LOWS TONIGHT WITH READINGS GENERALLY AROUND 70.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 418 AM EDT TUE SEP 2 2014
THE FRONTAL BOUNDARY REFERENCED IN THE SHORT TERM WILL BE DISSOLVING
EARLY IN THE LONG TERM PERIOD...BUT THERE SHOULD STILL BE DRY AIR IN
PLACE WEDNESDAY NIGHT...ESPECIALLY ALOFT. IF ANY CONVECTIVE PRECIP
CAN DEVELOP OFF OF LOW LEVEL MOISTURE ON WEDNESDAY AFTERNOON...IT
SHOULD DIE OUT BY NIGHT AS HEATING IS LOST AND SUPPORT ALOFT WILL
LIKELY BE LACKING.
DEEPER MOISTURE WILL MAKE A COMEBACK LATE IN THE WEEK AND MAY FUEL
A RESURGENCE OF SHOWERS AND THUNDERSTORMS...BUT A SUBTROPICAL RIDGE
ALOFT OVER THE SE CONUS WILL HELP TO KEEP COVERAGE LIMITED FOR A
WHILE. THE RIDGE WILL WEAKEN AND GET SUPPRESSED BY A BROAD TROUGH
DROPPING SE INTO THE NE CONUS DURING THE WEEKEND. THIS WILL ALLOW A
COLD FRONT TO MOVE INTO OUR REGION FROM THE NW. THE SCENARIO WILL
ALLOW AN INCREASE IN PRECIP COVERAGE...WITH A PEAK EXPECTED ON
SATURDAY. EVEN THOUGH THE FRONT SHOULD PASS BY SUNDAY...THE MODELS
STILL LEAVE SOME QUESTION AS TO HOW EFFECTIVE THE FRONT WILL BE AT
BRINGING IN A DRIER AIR MASS. HAVE HELD ONTO LOW POPS IN THE
AFTERNOON AND EVENING ON SUNDAY AND MONDAY...ESPECIALLY IN OUR SE
COUNTIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 649 AM EDT TUE SEP 2 2014
MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES OVER THE NEXT 24
TO 36 HOURS. A COLD FRONT WILL DROP SOUTH INTO EASTERN KENTUCKY
TODAY AND COULD SPAWN SCATTERED TO NUMEROUS THUNDERSTORMS THIS
AFTERNOON. PLAN TO STICK WITH THE VCTS THIS AFTERNOON AS
TIMING...COVERAGE...AND UNCERTAINTY ARE TOO GREAT TO GO WITH A
THUNDERSTORM PREVAILING GROUP. ACTIVITY SHOULD WANE BY MID TO LATE
EVENING WITH A QUIET NIGHT EXPECTED TONIGHT. HOWEVER...AS SKIES CLEAR
AND CALM WINDS...WE SHOULD SET THE STAGE FOR BETTER FOG PRODUCTION
TONIGHT...ESPECIALLY IF WE GET ANY RAIN TODAY. THUS...WILL TAKE
AIRPORTS BELOW MINIMUMS LATE TONIGHT WITH THE FOG.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...KAS
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1045 AM EDT TUE SEP 2 2014
.UPDATE...
ISSUED AT 1044 AM EDT TUE SEP 2 2014
LIMITED CHANGES TO THE GOING FORECAST. MAIN CHANGE WAS TO THE
THICKNESS OF THE MID-HIGH CLOUDS STREAMING NORTHEAST ACROSS THE
AREA THIS MORNING AND HAVE BUMPED THE FORECAST UP TO MOSTLY CLOUDY
OVER THE CENTRAL U.P. AS THIS MOVES THROUGH. DO HAVE SOME CONCERN ON
THE IMPACT THE CLOUDS WILL HAVE ON DIURNAL HEATING TODAY AND IN TURN
SHOWERS DEVELOPING THIS AFTERNOON. HAVE NOTICED A TREND IN THE
HIGH-RES MODELS (HRRR...NAMDNG...AND OUR LOCAL WRF-ARW) TO DEVELOP
THE SHOWERS A LITTLE FARTHER TO THE EAST (GENERALLY EASTERN
MARQUETTE/MENOMINEE COUNTIES AND EASTWARD)...AND HAVE ADJUSTED THE
POPS SLIGHTLY TOWARDS THAT IDEA. THE EASTERN U.P. STILL LOOKS TO
HAVE THE BEST CHANCES DUE TO LAKE BREEZE CONVERGENCE AND STORM
MOTION VECTORS PUSHING SHOWERS EASTWARD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 500 AM EDT TUE SEP 2 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD LOW AMPLITUDE
MID/UPPER LEVEL TROUGH THROUGH FROM THE NRN PLAINS INTO THE UPPER MS
VALLEY AND WRN GREAT LAKES WITH SEVERAL WEAK EMBEDDED SHORTWAVES.
ONE WAS LOCATED FROM SW MN INTO NW IA WHILE ANOTHER UPSTREAM SHRTWV
WAS MOVING THROUGH NORTH DAKOTA. AT THE SFC...WRLY FLOW PREVAILED
ACROSS UPPER MI BETWEEN A 987 MB LOW NEAR JAMES BAY AND A WEAK RIDGE
INTO THE CNTRL PLAINS.IR LOOP SHOWED MAINLY CLEAR SKIES ACROSS MOST
OF THE CWA BUT WITH INCREASING CLOUDS FROM MN INTO NW WI AND WRN
UPPER MI AHEAD OF THE SW MN SHRTWV.
TODAY...MOST OF THE FORCING ASSOCIATED WITH THE MN SHRTWV IS
EXPECTED TO REMAIN SOUTH OF UPPER MI. HOWEVER...THE COMBINATION OF
DAYTIME HEATING AND 850-600 MB LAPSE RATES TO NEAR 7.5C/KM AND LOW
LEVEL CONV ALONG LAKE BREEZE BOUNDARIES(ESPECIALLY OVER THE EAST)
WILL SUPPORT ISOLD/SCT SHRA BY THIS AFTERNOON. AS THE NORTH DAKOTA
SHRTWV NEAR BY MID TO LATE AFTERNOON SOME ADDITIONAL WEAK QVECTOR
CONV MAY ALSO CONTRIBUTE TO PCPN CHANCES. ALTHOUGH MLCAPE VALUES
INTO THE 400-800 J/KG RANGE WILL BE MARGINAL FOR TS...SOME ISOLD COULD
DEVELOP. WITH FREEZING HEIGHTS ONLY NEAR 9K-10K FT...SOME SMALL HAIL
MAY BE POSSIBLE.
TONIGHT...WITH THE LOSS OF DAYTIME HEATING AND THE SHRTWVS EXITING
TO THE EAST...ANY PCPN SHOULD QUICKLY DIMINISH. WITH THE FAST
MID/UPPER LEVEL FLOW ACROSS THE NRN CONUS...MODELS SUGGEST THAT
ANOTHER WEAK SHRTWV COULD MOVE THROUGH THE NRN LAKES AND PRODUCE
SOME LIGHT PCPN. HOWEVER...WITH VERY LIMITED MOISTURE AND LITTLE
INSTABILITY...CONFIDENCE IN ADDITIONAL PCPN DEVELOPING WAS LOW AND NO
ADDITIONAL RAIN WAS MENTIONED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 401 AM EDT TUE SEP 2 2014
THOUGH ACTIVE WEDNESDAY NIGHT INTO THURSDAY EVENING...THE REST OF
LONG TERM WILL BE QUIET AS HIGH PRESSURE DOMINATES FROM FRIDAY INTO
EARLY NEXT WEEK.
STARTING ON WEDNESDAY...WEAKER SHORTWAVES WORK THEIR WAY ACROSS
NORTHERN PLAINS AND TO UPPER GREAT LAKES BY LATE IN THE DAY IN A
ZONAL FLOW PATTERN ALOFT. LARGE SCALE LIFT IS PRESENT BUT THERE IS
NOT MUCH FOR A STRONGER SHORTWAVE AND ALSO OVERALL MOISTURE IS
LIMITED. BULK OF SHRA/TSRA LATER ON WEDNESDAY SHOULD STAY WEST OF
UPR MICHIGAN...MAINLY OVER CENTRAL AND SOUTHERN MINNESOTA CLOSER TO
SFC WARM FRONT AND BUILDING INSTABILITY. COULD SEE ISOLD SHRA/TSRA
OVER WESTERN LK SUPERIOR OR EVEN FAR WEST UPR MICHIGAN DUE TO
GENERAL H85-H7 WARM AIR ADVECTION AND MID-LEVEL MOISTURE ADVECTION.
TEMPS ON WEDNESDAY SHOULD PUSH INTO THE UPPER 70S OR LOWER 80S EVEN
WITH SCT-BKN MID CLOUDS IN THE AFTN.
POTENTIAL FOR PERIOD OF ACTIVE WEATHER WEDNESDAY NIGHT INTO THURSDAY
MORNING AS THE APPROACH OF A SFC LOW OVER THE NORTHERN PLAINS INCREASES
LOW-LEVEL JET /40 KTS AT H85/ INTO THE UPPER GREAT LAKES. SINCE THERE
IS NOT REALLY A STRONG SHORTWAVE MOVING THROUGH AT THAT TIME THOUGH...THINK
THAT THE BULK OF SHRA/TSRA WILL BE VCNTY OF WHERE LOW- LEVEL JET
INTERSECTS THE SFC-H85 WARM FRONT. BASED ON SFC WINDS AND DWPNTS...BEST
GUESS AT LOCATION OF THAT BOUNDARY IS FM CNTRL MN INTO WESTERN WI
WEDNESDAY NIGHT. MAX INSTABILITY BOTH IN TERMS OF MLCAPE AND ELEVATED
MUCAPE WILL BE MAXIMIZED OVER MUCH OF MINNESOTA AND INTO WISCONSIN
WITH INSTABILITY TRAILING OFF CONSIDERABLY INTO UPR MICHIGAN AND LK
MICHIGAN/LOWER MICHIGAN. MAJORITY OF MODELS INDICATE WIDESPREAD QPF
OVER UPR MICHIGAN WEDNESDAY NIGHT...BUT HAVE MY DOUBTS ON THIS AS
MOST OF THE HEAVY SHRA/TSRA COULD END UP FARTHER SOUTH ALONG WARM
FRONT AND ALSO BASED ON H85-H3 THICKNESSES WHICH...ALONG WITH FORWARD
PROPAGATING CORFIDI VECTORS...CAN BE USED TO DETERMINE GENERAL MOTION
OF AN MCS. SIMILAR TO EARLIER IN THE NIGHT...THERE IS STILL MID-LEVEL
MOISTURE ADVECTION FARTHER NORTH OF THE BOUNDARY THOUGH SO CANNOT
COMPLETELY RULE OUT SHRA/TSRA MAKING IT ACROSS UPR MICHIGAN. ANOTHER
FACTOR THAT COULD BUMP SHRA/TSRA FARTHER NORTH INTO THE CWA IS
INCREASING CAPPING THAT DEVELOPS IN THE H8-H7 LAYER OUT AHEAD OF THE
SFC LOW. AT THIS POINT THOUGH IT APPEARS THAT MAIN EXTENT OF CAPPING
WILL REMAIN BACK OVER THE CENTRAL PLAINS ON WEDNESDAY NIGHT.
GIVEN THE CONCERNS ABOUT TSRA OVERAGE...BACKED DOWN A BIT ON THE
HIGHER POPS WE HAD GOING BUT DID KEEP POPS HIGH CHANCE TO LOW END
LIKELY WITH BETTER CHANCES OVER THE WEST INITIALLY SHIFTING TO THE
EAST FOLLOWING THE TREND OF H7-H5 Q-VECTOR CONVERGENCE TIED TO
INITIAL WEAK SHORTWAVE AND ALSO WHERE THIS FORCING SYNCS UP WITH
GREATER MID-LEVEL MOISTURE TRANSPORT. TSRA INTENSITY SHOULD DIMINISH
INTO THE EAST BY LATE WED NIGHT INTO THURSDAY MORNING AS SHRA/TSRA
OUTRUN GREATER POOL OF INSTABILITY OVER MINNESOTA AND WISCONSIN.
FOR THURSDAY...RETAINED MUCH OF THE PREVIOUS FORECAST SHOWING TREND
TOWARD LOWER POPS BY LATE THURSDAY MORNING IN WAKE OF THE INITIAL
SHRA/TSRA MOVING EAST THEN POPS RAMPING BACK UP IN THE AFTN WITH
POSSIBLE ADDITIONAL SHRA/TSRA AHEAD OF APPROACHING COLD FRONT.
CAPPING SHOULD INCREASE MARKEDLY BY LATE MORNING/EARLY AFTN BASED
ON FORECAST SOUNDINGS SO THIS WILL IMPACT ADDITIONAL DEVELOPMENT OF
SHRA/TSRA. COULD GET QUITE WARM WITH EVEN JUST A LITTLE CLEARING.
MIXING TO H9 WITH SHARPER INVERSION AROUND THAT LEVEL SHOWN ON
SOUNDINGS MAY BE CONSERVATIVE BUT STILL RESULTS IN HIGHS AROUND 80
OVER MUCH OF CWA. NUDGED TEMPS UP INTO THE LOWER 80S AS A STARTING
POINT...BUT A MUGGY DAY /SFC DWPNTS 65-70/ WITH MID 80S IS CERTAINLY
POSSIBLE IN SOME AREAS. PRIMARY SHORTWAVE DRIVING THE COLD FRONT WILL
BE JUST NORTH OF MINNESOTA BY LATE THURSDAY AFTN. GIVEN THE WARM AND
HUMID AIRMASS...MLCAPES AHEAD OF THE FRONT OVER WEST HALF OF CWA
COULD PUSH OVER 2500J/KG...BUT MAIN QUESTIONS ARE HOW MUCH DEEPER
MOISTURE WILL BE AROUND AHEAD OF THE FRONT AND WILL CAPPING IN THE
H8-H7 LAYER BE TOO STRONG TO PROHIBIT SHRA/TSRA FROM DEVELOPING?
BASED ON CONSENSUS OF MODELS AND LATEST TRENDS...SEEMS THAT THERE IS
A RISK OF STORMS FORMING MID-LATE THURSDAY AFTN OVER THE WEST AND
AFFECTING REST OF CWA INTO THE EARLY EVENING AS BETTER MOISTURE IS
RE-INTRODUCED INTO THE AREA FM THE WEST/SOUTHWEST AND LIFT INCREASES
AND CAPPING DECREASES AS SHORTWAVE AND H5 SPEED MAX DRAW CLOSER. GIVEN
THE DEGREE OF INSTABILITY...IF STORMS FORM...SEVERE WEATHER POTENTIAL
IS ELEVATED AS 0-6KM SHEAR IS OVER 45 KTS AND 0-3KM SHEAR IS OVER 30
KTS. THE FORECASTED INSTABILITY...IF IT IS INDEED REALIZED...AND
SUCH SHEAR WOULD SUPPORT ROTATING/SUPERCELL TYPE STORMS AND ALSO
POTENTIAL FOR STORMS CONSOLIDATING INTO SEVERE WIND GUST PRODUCING
MCS ALONG THE COLD FRONT. A CONDITIONAL RISK ATTM...BUT CERTAINTLY
WORTH MONITORING AS WE GET CLOSER TO THIS TIME FRAME. SPC DAY3
OUTLOOK HIGHLIGHTS WI INTO WEST HALF OF UPR MICHIGAN WITH A 15 PCT
RISK FOR SEVERE /SLIGHT CATEGORICAL RISK/. WILL MENTION POTENTIAL
FOR SEVERE IN THE MORNING HAZARDOUS WEATHER OUTLOOK.
ONCE THE COLD FRONT SLIDES THROUGH ON THURSDAY NIGHT...ANY LINGERING
SHRA/TSRA WILL QUICKLY COME TO AN END BY THE OVERNIGHT SOUTH AND
EAST CWA. MAIN ISSUE LATE THURSDAY NIGHT INTO FRIDAY WILL BE GUSTY
NORTHWEST WINDS ON LK SUPERIOR AS IT BECOMES UNSTABLE IN THE 1000-900MB
LAYER. MIXED LAYER WINDS ARE OVER 30 KTS SO IT COULD BE GUSTY ALONG
THE LK SUPERIOR SHORE TO BEGIN THE DAY ON FRIDAY. DUE TO PRESSURE
RISES BTWN DEPARTING LOW AND APPROACHING HIGH...EVEN HIGHER WINDS
WOULD NOT BE OUT OF QUESTION. INCREASING WAVE ACTION WOULD ALSO LEAD
TO HIGH SWIM RISK ON BEACHES FROM MARQUETTE TO GRAND MARAIS.
QUIET WEATHER FOR THE WEEKEND AS IT LOOKS NOW. HIGH PRESSURE SETTLES
OVERHEAD AND STAYS IN PLACE INTO EARLY NEXT WEEK. TEMPS AT NIGHT MAY
DIP BLO 40 DEGREES IN THE INTERIOR. DAYTIME HIGHS WILL BE SEASONABLY
COOL IN THE 60S FOR MOST AREAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 738 AM EDT TUE SEP 2 2014
EXPECT VFR CONDITIONS TO PREVAIL THIS FCST PERIOD WITH RELATIVELY
DRY LOW LEVEL AIR DOMINATING. AN APPROACHING UPPER DISTURBANCE ALONG
WITH DAYTIME HEATING AND DESTABILIZATION COULD CAUSE SOME -SHRA AT
SAW AND PERHAPS IWD THIS AFTN...BUT THE DRY LOW LEVEL AIR SHOULD
MAINTAIN PREDOMINANT VFR WX EVEN IF THE -SHRA OCCUR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 500 AM EDT TUE SEP 2 2014
WINDS WILL BE 20 KNOTS OR LESS THROUGH MOST OF THIS FORECAST PERIOD
EXCEPT FOR THU NIGHT INTO FRI WHEN WEST TO NORTHWEST WINDS BEHIND A
STRONG COLD FRONT WILL APPROACH 30 KNOTS. THIS WILL BE THE WHEN THE
STRONGEST WINDS OCCUR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
739 AM EDT TUE SEP 2 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 500 AM EDT TUE SEP 2 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD LOW AMPLITUDE
MID/UPPER LEVEL TROUGH THROUGH FROM THE NRN PLAINS INTO THE UPPER MS
VALLEY AND WRN GREAT LAKES WITH SEVERAL WEAK EMBEDDED SHORTWAVES.
ONE WAS LOCATED FROM SW MN INTO NW IA WHILE ANOTHER UPSTREAM SHRTWV
WAS MOVING THROUGH NORTH DAKOTA. AT THE SFC...WRLY FLOW PREVAILED
ACROSS UPPER MI BETWEEN A 987 MB LOW NEAR JAMES BAY AND A WEAK RIDGE
INTO THE CNTRL PLAINS.IR LOOP SHOWED MAINLY CLEAR SKIES ACROSS MOST
OF THE CWA BUT WITH INCREASING CLOUDS FROM MN INTO NW WI AND WRN
UPPER MI AHEAD OF THE SW MN SHRTWV.
TODAY...MOST OF THE FORCING ASSOCIATED WITH THE MN SHRTWV IS
EXPECTED TO REMAIN SOUTH OF UPPER MI. HOWEVER...THE COMBINATION OF
DAYTIME HEATING AND 850-600 MB LAPSE RATES TO NEAR 7.5C/KM AND LOW
LEVEL CONV ALONG LAKE BREEZE BOUNDARIES(ESPECIALLY OVER THE EAST)
WILL SUPPORT ISOLD/SCT SHRA BY THIS AFTERNOON. AS THE NORTH DAKOTA
SHRTWV NEAR BY MID TO LATE AFTERNOON SOME ADDITIONAL WEAK QVECTOR
CONV MAY ALSO CONTRIBUTE TO PCPN CHANCES. ALTHOUGH MLCAPE VALUES
INTO THE 400-800 J/KG RANGE WILL BE MARGINAL FOR TS...SOME ISOLD COULD
DEVELOP. WITH FREEZING HEIGHTS ONLY NEAR 9K-10K FT...SOME SMALL HAIL
MAY BE POSSIBLE.
TONIGHT...WITH THE LOSS OF DAYTIME HEATING AND THE SHRTWVS EXITING
TO THE EAST...ANY PCPN SHOULD QUICKLY DIMINISH. WITH THE FAST
MID/UPPER LEVEL FLOW ACROSS THE NRN CONUS...MODELS SUGGEST THAT
ANOTHER WEAK SHRTWV COULD MOVE THROUGH THE NRN LAKES AND PRODUCE
SOME LIGHT PCPN. HOWEVER...WITH VERY LIMITED MOISTURE AND LITTLE
INSTABILITY...CONFIDENCE IN ADDITIONAL PCPN DEVELOPING WAS LOW AND NO
ADDITIONAL RAIN WAS MENTIONED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 401 AM EDT TUE SEP 2 2014
THOUGH ACTIVE WEDNESDAY NIGHT INTO THURSDAY EVENING...THE REST OF
LONG TERM WILL BE QUIET AS HIGH PRESSURE DOMINATES FROM FRIDAY INTO
EARLY NEXT WEEK.
STARTING ON WEDNESDAY...WEAKER SHORTWAVES WORK THEIR WAY ACROSS
NORTHERN PLAINS AND TO UPPER GREAT LAKES BY LATE IN THE DAY IN A
ZONAL FLOW PATTERN ALOFT. LARGE SCALE LIFT IS PRESENT BUT THERE IS
NOT MUCH FOR A STRONGER SHORTWAVE AND ALSO OVERALL MOISTURE IS
LIMITED. BULK OF SHRA/TSRA LATER ON WEDNESDAY SHOULD STAY WEST OF
UPR MICHIGAN...MAINLY OVER CENTRAL AND SOUTHERN MINNESOTA CLOSER TO
SFC WARM FRONT AND BUILDING INSTABILITY. COULD SEE ISOLD SHRA/TSRA
OVER WESTERN LK SUPERIOR OR EVEN FAR WEST UPR MICHIGAN DUE TO
GENERAL H85-H7 WARM AIR ADVECTION AND MID-LEVEL MOISTURE ADVECTION.
TEMPS ON WEDNESDAY SHOULD PUSH INTO THE UPPER 70S OR LOWER 80S EVEN
WITH SCT-BKN MID CLOUDS IN THE AFTN.
POTENTIAL FOR PERIOD OF ACTIVE WEATHER WEDNESDAY NIGHT INTO THURSDAY
MORNING AS THE APPROACH OF A SFC LOW OVER THE NORTHERN PLAINS INCREASES
LOW-LEVEL JET /40 KTS AT H85/ INTO THE UPPER GREAT LAKES. SINCE THERE
IS NOT REALLY A STRONG SHORTWAVE MOVING THROUGH AT THAT TIME THOUGH...THINK
THAT THE BULK OF SHRA/TSRA WILL BE VCNTY OF WHERE LOW- LEVEL JET
INTERSECTS THE SFC-H85 WARM FRONT. BASED ON SFC WINDS AND DWPNTS...BEST
GUESS AT LOCATION OF THAT BOUNDARY IS FM CNTRL MN INTO WESTERN WI
WEDNESDAY NIGHT. MAX INSTABILITY BOTH IN TERMS OF MLCAPE AND ELEVATED
MUCAPE WILL BE MAXIMIZED OVER MUCH OF MINNESOTA AND INTO WISCONSIN
WITH INSTABILITY TRAILING OFF CONSIDERABLY INTO UPR MICHIGAN AND LK
MICHIGAN/LOWER MICHIGAN. MAJORITY OF MODELS INDICATE WIDESPREAD QPF
OVER UPR MICHIGAN WEDNESDAY NIGHT...BUT HAVE MY DOUBTS ON THIS AS
MOST OF THE HEAVY SHRA/TSRA COULD END UP FARTHER SOUTH ALONG WARM
FRONT AND ALSO BASED ON H85-H3 THICKNESSES WHICH...ALONG WITH FORWARD
PROPAGATING CORFIDI VECTORS...CAN BE USED TO DETERMINE GENERAL MOTION
OF AN MCS. SIMILAR TO EARLIER IN THE NIGHT...THERE IS STILL MID-LEVEL
MOISTURE ADVECTION FARTHER NORTH OF THE BOUNDARY THOUGH SO CANNOT
COMPLETELY RULE OUT SHRA/TSRA MAKING IT ACROSS UPR MICHIGAN. ANOTHER
FACTOR THAT COULD BUMP SHRA/TSRA FARTHER NORTH INTO THE CWA IS
INCREASING CAPPING THAT DEVELOPS IN THE H8-H7 LAYER OUT AHEAD OF THE
SFC LOW. AT THIS POINT THOUGH IT APPEARS THAT MAIN EXTENT OF CAPPING
WILL REMAIN BACK OVER THE CENTRAL PLAINS ON WEDNESDAY NIGHT.
GIVEN THE CONCERNS ABOUT TSRA OVERAGE...BACKED DOWN A BIT ON THE
HIGHER POPS WE HAD GOING BUT DID KEEP POPS HIGH CHANCE TO LOW END
LIKELY WITH BETTER CHANCES OVER THE WEST INITIALLY SHIFTING TO THE
EAST FOLLOWING THE TREND OF H7-H5 Q-VECTOR CONVERGENCE TIED TO
INITIAL WEAK SHORTWAVE AND ALSO WHERE THIS FORCING SYNCS UP WITH
GREATER MID-LEVEL MOISTURE TRANSPORT. TSRA INTENSITY SHOULD DIMINISH
INTO THE EAST BY LATE WED NIGHT INTO THURSDAY MORNING AS SHRA/TSRA
OUTRUN GREATER POOL OF INSTABILITY OVER MINNESOTA AND WISCONSIN.
FOR THURSDAY...RETAINED MUCH OF THE PREVIOUS FORECAST SHOWING TREND
TOWARD LOWER POPS BY LATE THURSDAY MORNING IN WAKE OF THE INITIAL
SHRA/TSRA MOVING EAST THEN POPS RAMPING BACK UP IN THE AFTN WITH
POSSIBLE ADDITIONAL SHRA/TSRA AHEAD OF APPROACHING COLD FRONT.
CAPPING SHOULD INCREASE MARKEDLY BY LATE MORNING/EARLY AFTN BASED
ON FORECAST SOUNDINGS SO THIS WILL IMPACT ADDITIONAL DEVELOPMENT OF
SHRA/TSRA. COULD GET QUITE WARM WITH EVEN JUST A LITTLE CLEARING.
MIXING TO H9 WITH SHARPER INVERSION AROUND THAT LEVEL SHOWN ON
SOUNDINGS MAY BE CONSERVATIVE BUT STILL RESULTS IN HIGHS AROUND 80
OVER MUCH OF CWA. NUDGED TEMPS UP INTO THE LOWER 80S AS A STARTING
POINT...BUT A MUGGY DAY /SFC DWPNTS 65-70/ WITH MID 80S IS CERTAINLY
POSSIBLE IN SOME AREAS. PRIMARY SHORTWAVE DRIVING THE COLD FRONT WILL
BE JUST NORTH OF MINNESOTA BY LATE THURSDAY AFTN. GIVEN THE WARM AND
HUMID AIRMASS...MLCAPES AHEAD OF THE FRONT OVER WEST HALF OF CWA
COULD PUSH OVER 2500J/KG...BUT MAIN QUESTIONS ARE HOW MUCH DEEPER
MOISTURE WILL BE AROUND AHEAD OF THE FRONT AND WILL CAPPING IN THE
H8-H7 LAYER BE TOO STRONG TO PROHIBIT SHRA/TSRA FROM DEVELOPING?
BASED ON CONSENSUS OF MODELS AND LATEST TRENDS...SEEMS THAT THERE IS
A RISK OF STORMS FORMING MID-LATE THURSDAY AFTN OVER THE WEST AND
AFFECTING REST OF CWA INTO THE EARLY EVENING AS BETTER MOISTURE IS
RE-INTRODUCED INTO THE AREA FM THE WEST/SOUTHWEST AND LIFT INCREASES
AND CAPPING DECREASES AS SHORTWAVE AND H5 SPEED MAX DRAW CLOSER. GIVEN
THE DEGREE OF INSTABILITY...IF STORMS FORM...SEVERE WEATHER POTENTIAL
IS ELEVATED AS 0-6KM SHEAR IS OVER 45 KTS AND 0-3KM SHEAR IS OVER 30
KTS. THE FORECASTED INSTABILITY...IF IT IS INDEED REALIZED...AND
SUCH SHEAR WOULD SUPPORT ROTATING/SUPERCELL TYPE STORMS AND ALSO
POTENTIAL FOR STORMS CONSOLIDATING INTO SEVERE WIND GUST PRODUCING
MCS ALONG THE COLD FRONT. A CONDITIONAL RISK ATTM...BUT CERTAINTLY
WORTH MONITORING AS WE GET CLOSER TO THIS TIME FRAME. SPC DAY3
OUTLOOK HIGHLIGHTS WI INTO WEST HALF OF UPR MICHIGAN WITH A 15 PCT
RISK FOR SEVERE /SLIGHT CATEGORICAL RISK/. WILL MENTION POTENTIAL
FOR SEVERE IN THE MORNING HAZARDOUS WEATHER OUTLOOK.
ONCE THE COLD FRONT SLIDES THROUGH ON THURSDAY NIGHT...ANY LINGERING
SHRA/TSRA WILL QUICKLY COME TO AN END BY THE OVERNIGHT SOUTH AND
EAST CWA. MAIN ISSUE LATE THURSDAY NIGHT INTO FRIDAY WILL BE GUSTY
NORTHWEST WINDS ON LK SUPERIOR AS IT BECOMES UNSTABLE IN THE 1000-900MB
LAYER. MIXED LAYER WINDS ARE OVER 30 KTS SO IT COULD BE GUSTY ALONG
THE LK SUPERIOR SHORE TO BEGIN THE DAY ON FRIDAY. DUE TO PRESSURE
RISES BTWN DEPARTING LOW AND APPROACHING HIGH...EVEN HIGHER WINDS
WOULD NOT BE OUT OF QUESTION. INCREASING WAVE ACTION WOULD ALSO LEAD
TO HIGH SWIM RISK ON BEACHES FROM MARQUETTE TO GRAND MARAIS.
QUIET WEATHER FOR THE WEEKEND AS IT LOOKS NOW. HIGH PRESSURE SETTLES
OVERHEAD AND STAYS IN PLACE INTO EARLY NEXT WEEK. TEMPS AT NIGHT MAY
DIP BLO 40 DEGREES IN THE INTERIOR. DAYTIME HIGHS WILL BE SEASONABLY
COOL IN THE 60S FOR MOST AREAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 738 AM EDT TUE SEP 2 2014
EXPECT VFR CONDITIONS TO PREVAIL THIS FCST PERIOD WITH RELATIVELY
DRY LOW LEVEL AIR DOMINATING. AN APPROACHING UPPER DISTURBANCE ALONG
WITH DAYTIME HEATING AND DESTABILIZATION COULD CAUSE SOME -SHRA AT
SAW AND PERHAPS IWD THIS AFTN...BUT THE DRY LOW LEVEL AIR SHOULD
MAINTAIN PREDOMINANT VFR WX EVEN IF THE -SHRA OCCUR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 500 AM EDT TUE SEP 2 2014
WINDS WILL BE 20 KNOTS OR LESS THROUGH MOST OF THIS FORECAST PERIOD
EXCEPT FOR THU NIGHT INTO FRI WHEN WEST TO NORTHWEST WINDS BEHIND A
STRONG COLD FRONT WILL APPROACH 30 KNOTS. THIS WILL BE THE WHEN THE
STRONGEST WINDS OCCUR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS JACKSON MS
1052 AM CDT TUE SEP 2 2014
.UPDATE...
SOME ADJUSTMENTS WERE MADE TO THE POPS AND QPF FOR THIS AFTERNOON
AND EVENING...AND MINOR ADJUSTMENTS WERE MADE TO TEMPERATURES. ALL
ELSE IS GENERALLY ON TRACK.
&&
.DISCUSSION...A DIFFICULT FORECAST SCENARIO EXISTS FOR TODAY
AS CONVECTIVE OUTFLOW PUSHES SOUTH ACROSS ARKANSAS AND TOWARD
NORTHWEST PORTIONS OF THE ARKLAMISS...WHILE THE BEST LOW LEVEL
CONVERGENCE SETS UP GENERALLY ALONG THE NATCHEZ TRACE CORRIDOR. THIS
PATTERN IS RESULTING IN LOW LEVEL DRY AIR ADVECTION AHEAD OF THE
SOUTHWARD MOVING BOUNDARY AND THIS MAY LIMIT CONVECTIVE DEVELOPMENT
LATER THIS AFTERNOON OVER PORTIONS OF NORTHEAST LOUISIANA INTO
WESTERN MS. HOWEVER...BASED ON THE LATEST HRRR AND LOCAL WRF
GUIDANCE...EXPECT CONSIDERABLE SHOWER/TSTM DEVELOPMENT ALONG THE
SAID MOIST-CONVERGENCE AXIS WHERE PRECIPITABLE WATER IN EXCESS OF TWO
INCHES AND SB CAPE ~3500 J/KG WILL EXIST. LAPSE RATES WILL BE
MARGINAL FOR GETTING A FEW SEVERE STORMS.
OVERALL... HAVE ADJUSTED POPS TO BETTER REFLECT THE ABOVE SCENARIO...
INCREASED THEM EAST AND DECREASED THEM OVER PORTIONS OF THE LA/MS
DELTA REGION...BUT THIS IS NOT A HIGH CONFIDENCE FORECAST GIVEN
10-15 KTS OF LOW LEVEL FLOW AND NUMEROUS OUTFLOW BOUNDARIES LIKELY TO
EXIST. /EC/
&&
.AVIATION...CEILINGS WERE SLOWLY LIFTING ACROSS THE REGION...WITH
MVFR CONDITIONS AT MOST LOCATIONS. THROUGH NOON...LOOK FOR CEILING
TO CONTINUE TO LIFT. SHOWERS WILL REMAIN IN THE VICINITY OF JACKSON
GOING INTO THE AFTERNOON. WITH CLOUDS LINGERING OVER THE AREA...NOT
SURE HOW MUCH THUNDER WILL BE AROUND...BUT WILL CONTINUE THE VCTS
FROM 20-24Z. A BOUNDARY OFF TO NORTHWEST WAS SLOWLY MOVING IN THIS
DIRECTION...BUT MODELS SUGGEST IT WILL NOT MAKE IT THIS FAR SOUTH.
MODELS SEEM TO DISAGREE ABOUT FOG DEVELOPMENT FOR TONIGHT BUT AGREE
STRATUS SHOULD NOT DEVELOP. WILL ADD PATCHY FOG TO ALL SITES FROM
8-12Z.
&&
.PREV DISCUSSION... /ISSUED 351 AM CDT TUE SEP 2 2014/
DISCUSSION...
TODAY THROUGH WEDNESDAY
GREATER COVERAGE OF SHOWERS AND THUNDERSTORMS EXPECTED TODAY VS.
YESTERDAY WITH SOME POSSIBLY ON THE STRONG TO BRIEFLY SEVERE SIDE IN
WEST AND SOUTHWEST AREAS. TEMPERATURES WILL RISE QUICKLY THROUGH
MORNING HOURS BUT BE TEMPERED BY SHOWER COVERAGE DURING THE AFTN.
A SWIFT MOVING S/WV TROUGH ACROSS THE CENTRAL PLAINS IS SUSTAINING A
MCS IN KS/OK/MO THIS MORNING AND IS ACTING TO FLATTEN THE ALREADY
WEAK H7-H5 RIDGING OVER THE LOWER MS VALLEY. HI-RES GUIDANCE
INDICATES THE MCS WILL SHIFT INTO OK/AR THROUGH THE DAWN HOURS AND
SLOWLY WEAKEN AS IT GUSTS OUT. HOWEVER, HRRR/ARW SUGGEST A
CONVERGENT BAND DEVELOPING FROM THIS OUTFLOW IN SOUTH AR AND NORTH LA
BY LATE MORNING TO EARLY AFTN THAT COULD SERVE AS A FOCUS FOR MORE
ORGANIZED ACTIVITY INTO WEST AND SOUTHWEST MS BY MID TO LATE AFTN.
AHEAD OF THIS BOUNDARY, IT SHOULD ALSO BE NOTED THAT WITH SUCH A WARM
START THIS MORNING, CONVECTIVE TEMPERATURES WILL BE REACHED 11AM-12PM
AND ISO/SCT SHOWERS/TSTORMS WILL LIKELY DEVELOP ACROSS THE I-20 AND
HWY 82 CORRIDORS. GREATER INSTABILITY WILL EXIST IN WEST IN
CONJUNCTION WITH POSSIBLE CONVERGENCE BAND AND THIS MAY PROMOTE
BETTER UPDRAFT STRENGTH AS SUPPORTED BY SPC SSEO OUTPUT. STORMS COULD
BECOME STRONG TO BRIEFLY SEVERE WITH LOCALIZED WINDS IN THE 40-60 MPH
RANGE AND FREQUENT LIGHTNING. WILL NOT FORMALLY INTRODUCE A LIMITED
THREAT OF SEVERE JUST YET AS TO MONITOR HI-RES TRENDS AND ALLOW FOR
MORNING SOUNDING ANALYSIS.
SHOWERS/STORMS WILL DIMINISH THROUGH THE MID EVENING HOURS BUT SOME
NEW ACTIVITY MAY DEVELOP IN NORTH MS ALONG AN ELEVATED BOUNDARY
EARLY WEDNESDAY MORNING AND HAVE PLACED 20% POPS FOR FAR NORTH TIER
COUNTIES. PWATS NEAR 2" WILL CONTINUE WEDNESDAY WITH ANOTHER ROUND
OF SHOWERS/STORMS EXPECTED DURING THE AFTERNOON HOURS. THIS ACTIVITY
ALSO SHOULD DECREASE THROUGH MID EVENING HOURS WITH QUIET
CONDITIONS OVERNIGHT THURSDAY EXPECTED. /ALLEN/
THURSDAY THROUGH MONDAY...
DEEP LAYERED RIDGE LOOKS TO REMAIN ANCHORED OVER THE LOWER CONUS
THROUGH THE PERIOD. THIS SHOULD KEEP THE MOIST AND UNSTABLE AIRMASS
LOCKED IN PLACE AND A CONTINUATION OF THE SENSIBLE WEATHER WE HAVE
BEEN EXPERIENCING.
WILL PRETTY MUCH HAVE TO CONTEND WITH AFTERNOON/EVENING AIRMASS
CONVECTION EACH DAY THROUGH THE EXTENDED TIME FRAME. ALTHOUGH
CONVECTIVE COVERAGE SHOULD REMAIN SCATTERED...STORMS MAY BE SOMEWHAT
MORE NUMEROUS OVER THE SOUTH WHERE INTERACTIONS WITH THE SEA BREEZE
MAY BE ENCOUNTERED. WENT CLOSE TO GFS MOS MAXIMUMS WITH HIGHS IN THE
LOW TO MID 90S AS BELIEVE THIS LEVEL OF WARMING WILL STILL BE LIKELY
GIVEN MID AFTERNOON CONVECTIVE INITIATION TIMES.
MOVING INTO THE WEEKEND...SUBTLE MID LEVEL TROFFINESS OVER THE
EASTERN PORTIONS OF THE COUNTRY WILL ALLOW A WEAK COLD FRONT TO EASE
INTO THE REGION FROM THE NORTH SATURDAY NIGHT/SUNDAY. THE BOUNDARY
LOOKS AS THOUGH IT WILL QUICKLY STALL OVER THE NORTH AND NOT OFFER
ANYMORE THAN AN INCREASE IN CONVECTIVE COVERAGE FOR THE REMAINDER OF
THE WEEKEND AND THE FIRST PART OF NEXT WEEK. WHILE THE COOL AIR
BEHIND THE BOUNDARY SHOULD STAY TO THE NORTH OF THE AREA...INCREASED
CONVECTION SUNDAY AND MONDAY SHOULD ONLY ALLOW MAXIMUMS TO REACH
AROUND 90...BUT OVERNIGHT LOWS WILL REMAIN IN THE LOWER 70S./26/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 92 73 94 72 / 50 27 32 19
MERIDIAN 93 72 94 71 / 49 24 41 17
VICKSBURG 92 72 94 72 / 51 24 24 19
HATTIESBURG 94 75 95 73 / 52 30 50 21
NATCHEZ 90 74 92 72 / 54 30 40 23
GREENVILLE 93 73 94 73 / 50 20 19 14
GREENWOOD 92 73 94 72 / 46 20 27 14
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
718 AM EDT TUE SEP 2 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE ACROSS THE AREA TODAY EXTENDING FROM LOW
PRESSURE TRACKING NORTHEAST ACROSS QUEBEC. HIGH PRESSURE WILL
EXPAND OVER THE OHIO VALLEY TONIGHT...THEN TO THE EAST COAST ON
WEDNESDAY. A WARM FRONT WILL LIFT NORTH ON THURSDAY AHEAD OF THE
NEXT LOW PRESSURE SYSTEM THAT WILL PASS NORTH OF THE GREAT LAKES
ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A SWATH OF RAIN CAN BE SEEN ON UPSTREAM RADARS SPREADING NORTHEAST
ACROSS INDIANA EARLY THIS MORNING. THIS RAIN WILL CONTINUE TO BE
PULLED NORTHEAST AHEAD OF THE SHORTWAVE ENERGY MOVING ACROSS THE
PLAINS. THE 00Z SOUNDING OUT OF ILX SHOWED QUITE A BIT OF DRY AIR IN
THE COLUMN AHEAD OF THIS DEEPER PUSH OF MOISTURE AND THIS NOW
RESIDES OVER THE FORECAST AREA EARLY THIS MORNING. THE STRONGER
MOISTURE ADVECTION IS FOCUSED NEAR 700MB AND THE DRIER LOW LEVEL AIR
MAY CAUSE SOME EVAPORATION INITIALLY. THE BETTER INSTABILITY WILL BE
LOCATED FARTHER SOUTH AND TRENDS HAVE BEEN FOR THE DEEP CONVECTION
TO RESIDE ON THE SE FLANK OF THE PRECIPITATION SHIELD. WILL CARRY A
HIGH POP FOR JUST ABOUT ALL AREAS THIS MORNING...ALTHOUGH WILL ONLY
CARRY A CHANCE OF THUNDERSTORMS(BETTER CHANCES OF THUNDERSTORMS WILL
BE LOCATED ALONG AND SOUTH OF INTERSTATE 70 IN CENTRAL OHIO).
PRECIPITATION AMOUNTS WILL GENERALLY BE A HALF INCH OR LESS.
LOW PRESSURE IS LOCATED JUST EAST OF JAMES BAY THIS MORNING WITH THE
TRAILING COLD FRONT STILL LOCATED NORTH OF LAKE ERIE. THIS WEAK
FRONT IS EXPECTED TO MOVE THROUGH TOLEDO AROUND NOON...CLEVELAND
EARLY THIS AFTERNOON AND YOUNGSTOWN BY LATE AFTERNOON. ALTHOUGH THE
INITIAL SURGE OF MOISTURE WILL EXIT TO THE EAST...THE FRONT WILL
INTERACT WITH THE LINGERING MOISTURE WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE EASTERN AREAS THIS AFTERNOON. THE STORM
PREDICTION CENTER HAS PLACED OUR SE TIER OF COUNTIES IN THE SLIGHT
RISK FOR SEVERE THUNDERSTORMS TODAY. EXPECTING A CONSIDERABLE AMOUNT
OF CLOUD COVER TO HAVE A LIMITING EFFECT ON HEATING/INSTABILITY
ALONG AND AHEAD OF THE FRONT THIS AFTERNOON. BETTER CHANCES OF
SEVERE WEATHER WILL BE LOCATED JUST SOUTH AND EAST OF THE AREA BUT
CAN NOT ENTIRELY RULE OUT A SEVERE STORM IF HEATING IS STRONGER THAN
EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
HIGH PRESSURE WILL EXPAND EASTWARD ACROSS THE OHIO VALLEY TONIGHT.
IT LOOKS LIKE A WEAK THERMAL TROUGH WILL LINGER OVER LAKE ERIE ON
THE NORTH SIDE OF THE HIGH THIS EVENING AND MAY PROVIDE ENOUGH
CONVERGENCE FOR A FEW SHOWERS TO DEVELOP OVER THE LAKE. LEFT A LOW
POP BOTH OVER THE LAKE AND ALONG THE EASTERN LAKESHORE FOR A PORTION
OF THE NIGHT. INLAND AREAS...ESPECIALLY OUR SOUTHERN COUNTIES COULD
SEE SOME FOG OR STRATUS GIVEN THE LINGERING BOUNDARY LAYER MOISTURE
COUPLED WITH CLEARING SKIES AND LIGHT WINDS. TEMPERATURES WILL
BOTTOM OUT IN THE UPPER 50S TO LOW 60S.
THE AIRMASS DOES NOT COOL MUCH WITH THE FRONTAL PASSAGE AND
TEMPERATURES ARE STILL EXPECTED TO BE A COUPLE DEGREES ABOVE NORMAL
ON WEDNESDAY. THE MAIN DIFFERENCE WILL BE FELT IN THE HUMIDITY WHICH
WILL BE LOWER AND MORE PLEASANT WITH DEWPOINTS NEAR 60 DEGREES.
MAINLY JUST SCATTERED CU ON WEDNESDAY ONCE ANY MORNING CLOUDS BURN
OFF.
HEIGHTS WILL REBOUND OVER THE AREA ON THURSDAY AND A WARM FRONT WILL
LIFT NORTH AHEAD OF THE NEXT LOW PRESSURE SYSTEM TRACKING OUT OF THE
PLAINS. THIS SYSTEM IS FORECAST TO TRACK ACROSS LAKE SUPERIOR THEN
CONTINUE NORTHEAST ACROSS ONTARIO AND QUEBEC. ENOUGH DRY AIR SHOULD
STILL BE IN PLACE ON THURSDAY FOR THE FORECAST AREA TO STAY DRY.
LEFT THE 20 POP IN THE FORECAST ON THURSDAY NIGHT AS MOISTURE DOES
START TO INCREASE ALTHOUGH THE MORE FOCUSED MOISTURE ADVECTION WILL
BE WELL TO THE NORTH. THE ASSOCIATED COLD FRONT WILL SINK SOUTH
TOWARDS THE AREA ON FRIDAY. LOWERED POPS DURING THE MORNING HOURS
AND ACROSS THE SOUTHERN COUNTIES THAT SHOULD STRUGGLE TO SEE ANY
PRECIPITATION UNTIL FRIDAY NIGHT. TEMPERATURES ON THURSDAY AND
FRIDAY WILL BE IN THE MID 80S...WITH A FEW SPOTS MAKING A RUN AT THE
UPPER 80S.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
NO BIG CHANGES TO THE MODELS FOR THE EXTENDED WITH GUIDANCE SHOWING
A COLD FRONT TO OUR SOUTH SATURDAY MORNING WITH DRIER AIR AND HIGH
MOVING IN FROM THE NORTH. DONT THINK THE DAY WILL BEGIN DRY HOWEVER
AS THE ECMWF REMAINS SLOWER THAN THE GFS IN MOVING MOISTURE OUT OF
THE AREA. WILL CONTINUE WITH CHANCE POPS THROUGH THE MORNING
SATURDAY BEFORE DROPPING TO A SLIGHT CHANCE ACROSS THE NORTH.
SATURDAY NIGHT THROUGH MONDAY LOOK DRY. TEMPS NEAR NORMAL AFTER AN
ABOVE NORMAL END TO THE WEEK.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
WEAK COLD FRONT TO OUR NORTHWEST NR A KFNT-KSBN LINE. FROM WILL
MOVE THROUGH THE AREA DURING THE DAY. CONVECTION FROM INDIANA
TRACKING ENE ACROSS CENTRAL AND SRN OHIO. WILL LIKELY SEE THUNDER
INTO NRN OHIO BUT KEPT MENTION OUT OF THE FAR NRN TAFS. HRRR MOVES
THIS PRECIP THROUGH DURING THE MORNING AND EARLY AFTERNOON WITH
POSSIBLY A FEW LINGERING SHOWERS FOR MID AFTERNOON. EXPECT MAINLY
MVFR CONDITIONS WITH AND JUST BEHIND THE PRECIP...LIFTING TO VFR 2
TO 4 HOURS AFTER PRECIP ENDS. EXPECT THE EVENING WILL BEGIN VFR
HOWEVER WITH LOW LEVEL MOISTURE IN PLACE...DRYING ALOFT AND HIGH
PRESSURE OVER THE AREA EXPECT MVFR AND POSSIBLY IFR CIGS/FOG TO
DEVELOP OVERNIGHT.
OUTLOOK...NON VFR LIKELY IN SHOWERS AND THUNDERSTORMS BY FRIDAY
EVENING INTO SATURDAY WITH THE NEXT COLD FRONT.
&&
.MARINE...
WILL BEGIN TODAY CLOSE TO SMALL CRAFT CRITERIA MAINLY EAST OF
CONNEAUT BUT FOR NOW WILL CONTINUE WITH A FORECAST JUST BELOW. WINDS
TODAY WILL BE FROM THE SOUTHWEST AHEAD OF A WEAK COLD FRONT DUE IN
LATE MORNING/EARLY AFTERNOON. WINDS WILL TURN WEST TO BRIEFLY
NORTHWEST BEHIND THE BOUNDARY. HIGH PRESSURE BUILDS IN TONIGHT AND
WEDNESDAY. THURSDAY THE HIGH WILL DRIFT EAST AND A LOW WILL BE
MOVING THROUGH THE NORTHERN PLAINS. THIS WILL AGAIN SETUP SOUTHWEST
FLOW ON THE LAKE THURSDAY INCREASING TO 10 TO 20 KNOTS. THE LOW WILL
MOVE THROUGH EASTERN CANADA FRIDAY DRAGGING A COLD FRONT ACROSS THE
LAKE DURING THE AFTERNOON. WINDS WILL TURN NORTHWEST FRIDAY NIGHT
AND SATURDAY BEHIND THE FRONT. ALTHOUGH CLOSE...NO NEAR TERM
HEADLINES FOR NOW. FRIDAY INTO SATURDAY WE COULD REACH SMALL CRAFT
CRITERIA AS WINDS TURN NORTHWEST.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
711 AM EDT TUE SEP 2 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE ACROSS THE AREA TODAY EXTENDING FROM LOW
PRESSURE TRACKING NORTHEAST ACROSS QUEBEC. HIGH PRESSURE WILL
EXPAND OVER THE OHIO VALLEY TONIGHT...THEN TO THE EAST COAST ON
WEDNESDAY. A WARM FRONT WILL LIFT NORTH ON THURSDAY AHEAD OF THE
NEXT LOW PRESSURE SYSTEM THAT WILL PASS NORTH OF THE GREAT LAKES
ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LIGHT RAIN HAS SPREAD INTO THE TOLEDO AREA AND WILL CONTINUE TO
PUSH EASTWARD. POPS REMAIN PRETTY HIGH WITH THE MORNING UPDATE
ALTHOUGH SHOWERS WILL NOT LAST THAT LONG IN SOME AREAS. DRY AIR
CAN ALREADY BE SEEN OVER NRN INDIANA AND THE COVERAGE AND
INTENSITY OF SHOWERS HAS SHOWN A DECREASING TREND. STILL THINK
MOST AREAS WILL SEE RAIN SO POPS REMAIN HIGH AND CAN BE LOWERED
THROUGH THE DAY AS RAIN EXITS TO THE EAST.
PREVIOUS DISCUSSION...A SWATH OF RAIN CAN BE SEEN ON UPSTREAM
RADARS SPREADING NORTHEAST ACROSS INDIANA EARLY THIS MORNING. THIS
RAIN WILL CONTINUE TO BE PULLED NORTHEAST AHEAD OF THE SHORTWAVE
ENERGY MOVING ACROSS THE PLAINS. THE 00Z SOUNDING OUT OF ILX
SHOWED QUITE A BIT OF DRY AIR IN THE COLUMN AHEAD OF THIS DEEPER
PUSH OF MOISTURE AND THIS NOW RESIDES OVER THE FORECAST AREA EARLY
THIS MORNING. THE STRONGER MOISTURE ADVECTION IS FOCUSED NEAR
700MB AND THE DRIER LOW LEVEL AIR MAY CAUSE SOME EVAPORATION
INITIALLY. THE BETTER INSTABILITY WILL BE LOCATED FARTHER SOUTH
AND TRENDS HAVE BEEN FOR THE DEEP CONVECTION TO RESIDE ON THE SE
FLANK OF THE PRECIPITATION SHIELD. WILL CARRY A HIGH POP FOR JUST
ABOUT ALL AREAS THIS MORNING...ALTHOUGH WILL ONLY CARRY A CHANCE
OF THUNDERSTORMS(BETTER CHANCES OF THUNDERSTORMS WILL BE LOCATED
ALONG AND SOUTH OF INTERSTATE 70 IN CENTRAL OHIO). PRECIPITATION
AMOUNTS WILL GENERALLY BE A HALF INCH OR LESS.
LOW PRESSURE IS LOCATED JUST EAST OF JAMES BAY THIS MORNING WITH THE
TRAILING COLD FRONT STILL LOCATED NORTH OF LAKE ERIE. THIS WEAK
FRONT IS EXPECTED TO MOVE THROUGH TOLEDO AROUND NOON...CLEVELAND
EARLY THIS AFTERNOON AND YOUNGSTOWN BY LATE AFTERNOON. ALTHOUGH THE
INITIAL SURGE OF MOISTURE WILL EXIT TO THE EAST...THE FRONT WILL
INTERACT WITH THE LINGERING MOISTURE WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS IN THE EASTERN AREAS THIS AFTERNOON. THE STORM
PREDICTION CENTER HAS PLACED OUR SE TIER OF COUNTIES IN THE SLIGHT
RISK FOR SEVERE THUNDERSTORMS TODAY. EXPECTING A CONSIDERABLE AMOUNT
OF CLOUD COVER TO HAVE A LIMITING EFFECT ON HEATING/INSTABILITY
ALONG AND AHEAD OF THE FRONT THIS AFTERNOON. BETTER CHANCES OF
SEVERE WEATHER WILL BE LOCATED JUST SOUTH AND EAST OF THE AREA BUT
CAN NOT ENTIRELY RULE OUT A SEVERE STORM IF HEATING IS STRONGER THAN
EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
HIGH PRESSURE WILL EXPAND EASTWARD ACROSS THE OHIO VALLEY TONIGHT.
IT LOOKS LIKE A WEAK THERMAL TROUGH WILL LINGER OVER LAKE ERIE ON
THE NORTH SIDE OF THE HIGH THIS EVENING AND MAY PROVIDE ENOUGH
CONVERGENCE FOR A FEW SHOWERS TO DEVELOP OVER THE LAKE. LEFT A LOW
POP BOTH OVER THE LAKE AND ALONG THE EASTERN LAKESHORE FOR A PORTION
OF THE NIGHT. INLAND AREAS...ESPECIALLY OUR SOUTHERN COUNTIES COULD
SEE SOME FOG OR STRATUS GIVEN THE LINGERING BOUNDARY LAYER MOISTURE
COUPLED WITH CLEARING SKIES AND LIGHT WINDS. TEMPERATURES WILL
BOTTOM OUT IN THE UPPER 50S TO LOW 60S.
THE AIRMASS DOES NOT COOL MUCH WITH THE FRONTAL PASSAGE AND
TEMPERATURES ARE STILL EXPECTED TO BE A COUPLE DEGREES ABOVE NORMAL
ON WEDNESDAY. THE MAIN DIFFERENCE WILL BE FELT IN THE HUMIDITY WHICH
WILL BE LOWER AND MORE PLEASANT WITH DEWPOINTS NEAR 60 DEGREES.
MAINLY JUST SCATTERED CU ON WEDNESDAY ONCE ANY MORNING CLOUDS BURN
OFF.
HEIGHTS WILL REBOUND OVER THE AREA ON THURSDAY AND A WARM FRONT WILL
LIFT NORTH AHEAD OF THE NEXT LOW PRESSURE SYSTEM TRACKING OUT OF THE
PLAINS. THIS SYSTEM IS FORECAST TO TRACK ACROSS LAKE SUPERIOR THEN
CONTINUE NORTHEAST ACROSS ONTARIO AND QUEBEC. ENOUGH DRY AIR SHOULD
STILL BE IN PLACE ON THURSDAY FOR THE FORECAST AREA TO STAY DRY.
LEFT THE 20 POP IN THE FORECAST ON THURSDAY NIGHT AS MOISTURE DOES
START TO INCREASE ALTHOUGH THE MORE FOCUSED MOISTURE ADVECTION WILL
BE WELL TO THE NORTH. THE ASSOCIATED COLD FRONT WILL SINK SOUTH
TOWARDS THE AREA ON FRIDAY. LOWERED POPS DURING THE MORNING HOURS
AND ACROSS THE SOUTHERN COUNTIES THAT SHOULD STRUGGLE TO SEE ANY
PRECIPITATION UNTIL FRIDAY NIGHT. TEMPERATURES ON THURSDAY AND
FRIDAY WILL BE IN THE MID 80S...WITH A FEW SPOTS MAKING A RUN AT THE
UPPER 80S.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
NO BIG CHANGES TO THE MODELS FOR THE EXTENDED WITH GUIDANCE SHOWING
A COLD FRONT TO OUR SOUTH SATURDAY MORNING WITH DRIER AIR AND HIGH
MOVING IN FROM THE NORTH. DONT THINK THE DAY WILL BEGIN DRY HOWEVER
AS THE ECMWF REMAINS SLOWER THAN THE GFS IN MOVING MOISTURE OUT OF
THE AREA. WILL CONTINUE WITH CHANCE POPS THROUGH THE MORNING
SATURDAY BEFORE DROPPING TO A SLIGHT CHANCE ACROSS THE NORTH.
SATURDAY NIGHT THROUGH MONDAY LOOK DRY. TEMPS NEAR NORMAL AFTER AN
ABOVE NORMAL END TO THE WEEK.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
WEAK COLD FRONT TO OUR NORTHWEST WITH BEST GUESS POSITION FROM
CENTRAL LWR MI SW INTO MO. MCS ACROSS MO AND SRN IL WHILE A FEW
LINGERING SHOWERS ALONG WITH A LITTLE THUNDER ACROSS FAR EASTERN
ERIE COUNTY PA AND EAST INTO WRN NY. THAT ACTIVITY WILL CONTINUE
EAST OUT OF THE AREA OVER THE NEXT HOUR OR TWO. HRRR DOES SHOW
SOME REDEVELOPMENT OVER ERIE COUNTY AND WILL ACCOUNT FOR THAT IN
THE TAF. OTHERWISE MAINLY VFR ACROSS THE AREA THIS HOURS ALTHOUGH
THE HRRR DOES SHOW ACTIVITY TO OUR WEST MOVING INTO THE AREA
TOWARDS MORNING. EXPECT THE BULK OF THE CONVECTION TO REMAIN SOUTH
OF OUR AREA...TRACKING ACROSS CENTRAL AND SRN OHIO...HOWEVER SO
EXPECT SOME PRECIP TO EXTEND NORTH AND AFFECT THE AREA. BROUGHT
SHOWERS INTO KTOL/KFDY AROUND 10Z AND KCLE/KMFD 11-12Z AND KERI-
KYNG 14-15Z. ALSO INCLUDED VCTS BUT FOR NOW DID NOT INCLUDE THUNDER IN
TEMPO GROUPS. HELD ONTO MVFR CIGS THROUGH THE BALANCE OF THE
MORNING GIVEN DEEP HIGH RH ACROSS THE AREA. DRIER AIR SHOULD BEGIN
MOVING IN THROUGH THE AFTERNOON.
OUTLOOK...NON VFR LIKELY IN SHOWERS AND THUNDERSTORMS BY FRIDAY
EVENING INTO SATURDAY WITH THE NEXT COLD FRONT.
&&
.MARINE...
WILL BEGIN TODAY CLOSE TO SMALL CRAFT CRITERIA MAINLY EAST OF
CONNEAUT BUT FOR NOW WILL CONTINUE WITH A FORECAST JUST BELOW. WINDS
TODAY WILL BE FROM THE SOUTHWEST AHEAD OF A WEAK COLD FRONT DUE IN
LATE MORNING/EARLY AFTERNOON. WINDS WILL TURN WEST TO BRIEFLY
NORTHWEST BEHIND THE BOUNDARY. HIGH PRESSURE BUILDS IN TONIGHT AND
WEDNESDAY. THURSDAY THE HIGH WILL DRIFT EAST AND A LOW WILL BE
MOVING THROUGH THE NORTHERN PLAINS. THIS WILL AGAIN SETUP SOUTHWEST
FLOW ON THE LAKE THURSDAY INCREASING TO 10 TO 20 KNOTS. THE LOW WILL
MOVE THROUGH EASTERN CANADA FRIDAY DRAGGING A COLD FRONT ACROSS THE
LAKE DURING THE AFTERNOON. WINDS WILL TURN NORTHWEST FRIDAY NIGHT
AND SATURDAY BEHIND THE FRONT. ALTHOUGH CLOSE...NO NEAR TERM
HEADLINES FOR NOW. FRIDAY INTO SATURDAY WE COULD REACH SMALL CRAFT
CRITERIA AS WINDS TURN NORTHWEST.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1026 AM CDT TUE SEP 2 2014
.UPDATE...
SEE MORNING UPDATE.
&&
.DISCUSSION...
12Z SOUNDINGS SHOW PW VALUES BETWEEN 2.1 AND 2.2 INCHES AND THIS
IS SUPPORTED BY GPS MET DATA, CONVECTIVE TEMPS ARE BETWEEN 86 AND
88 DEGREES TODAY AND THIS THRESHOLD WILL BE MET EASILY. A WELL
DEVELOPED S/WV EXTENDS FROM CENTRAL ARKANSAS INTO CENTRAL TEXAS
WHICH SERVE AS ANOTHER FOCUS FOR SHRA/TSRA. UPPER LEVEL RIDING HAS
INCHED CLOSER TO SE TX WHICH WILL IMPART A BIT OF SUBSIDENCE. THE
RAP IS VERY AGGRESSIVE WITH RAINFALL THIS AFTN WHILE THE
HRRR/ARW-EAST REMAIN MORE BENIGN. THE RAP WAS OVERDONE YESTERDAY
AND DID NOT INITIALIZE ALL THAT WELL SO HAVE LEANED TOWARD A HRRR/WRF
BLEND. CHANCE POPS LOOK APPROPRIATE SO NO CHANGES TO THE POP/WX
GRIDS. DID BUMP MAX T GRIDS UP A FEW DEGREES TO MATCH TRENDS/OBS.
AS FOR TS DOLLY...THE STORM WILL PROBABLY MAKE LANDFALL A BIT
EARLIER...SOMETIME THIS EVENING. THE MAIN EFFECT FOR SE TX WILL BE
INCREASING SWELLS OVER THE OFFSHORE MARINE ZONES AND A 1.0-1.5
FOOT BUMP UP IN TIDE LEVELS. NEW ZONES OUT BY 1030 AM. 43
&&
.PREV DISCUSSION... /ISSUED 629 AM CDT TUE SEP 2 2014/
AVIATION...
MOSTLY SCT CLOUDS ACROSS THE AREA THIS MORNING. SHRA/TSRA MOVING TO
THE NNW OUT OF THE GULF ARE SO FAR HAVING TROUBLE MAKING IT PAST THE
COASTAL COUNTIES. ACTIVITY SHOULD SPREAD/DEVELOP FURTHER INLAND LATER
THIS MORNING AND THIS AFTERNOON DUE TO DAYTIME HEATING AND INCREASING
INSTABILITY. GOING WITH VCTS/TSRA FOR THIS MORNING NEAR THE COAST AND
INLAND THIS AFTERNOON. THINGS SHOULD QUIET DOWN THIS EVENING WITH THE
LOSS OF HEATING. MVFR CEILING DEVELOPMENT POSSIBLE LATE TONIGHT THROUGH
EARLY WEDNESDAY MORNING. 42
PREV DISCUSSION... /ISSUED 405 AM CDT TUE SEP 2 2014/
DISCUSSION...
A FEW SHOWERS ARE MOVING NORTHWARD ACROSS THE COASTAL WATERS THIS
MORNING IN ASSOCIATION WITH AN AREA OF DEEPER MOISTURE WHICH IS
APPROACHING THE UPPER TEXAS COAST. FURTHER TO THE SOUTH...TD 5 HAS
STRENGTHENED INTO TROPICAL STORM DOLLY THIS MORNING. THE CENTER OF
THE SYSTEM HAS FORMED A BIT FURTHER NORTH THAT PREVIOUSLY EXPECTED
WHICH HAS CAUSED A CORRESPONDING SHIFT IN THE FORECAST TRACK. THE
ONLY ADDITIONAL IMPACTS TO SOUTHEAST TEXAS WILL BE SOME SLIGHTLY
HIGHER SEAS OFFSHORE AS THE NEW TRACK STILL TAKES THE SYSTEM INTO
MEXICO WELL SOUTH OF THE BORDER.
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP INLAND LATER
THIS MORNING AS MOISTURE STREAMS BACK INTO THE REGION. COVERAGE
SHOULD INCREASE ACROSS OUR NORTHERN COUNTIES LATE THIS AFTERNOON
AS A PASSING SHORTWAVE BRINGS ADDITIONAL LIFT TO THE REGION. GIVEN
THE RICH MOISTURE A FEW BRIEF HEAVY DOWNPOURS WILL BE POSSIBLE
WITH THE ACTIVITY TODAY. HIGH TEMPERATURES SHOULD REMAIN IN THE
LOW TO MID 90S AREAWIDE WITH THE PRECIPITATION AND GREATER CLOUD
COVER.
ONLY SLIGHT CHANGES FOR THE MID TO EXTENDED RANGE FORECAST THIS
MORNING. THE UPPER LEVEL PATTERN OVERHEAD REMAINS RELATIVELY
UNCHANGED THROUGH THE WEEK WITH A BROAD FLAT RIDGE ACROSS THE
SOUTHERN UNITED STATES. THIS WILL ALLOW FOR CONTINUED DIURNALLY
DRIVEN SHOWERS AND THUNDERSTORMS WITH HIGH TEMPERATURES IN THE LOW
TO MID 90S...NEAR THE NORMALS FOR THE FIRST WEEK OF SEPTEMBER. 38
MARINE...
TROPICAL STORM DOLLY IS LOCATED IN THE BAY OF CAMPECHE EARLY
THIS MORNING. BASED ON THE CURRENT FORECAST...DOLLY IS EXPECTED
TO APPROACH THE COAST OF MEXICO BY TONIGHT AND MOVE INLAND BY
WEDNESDAY MORNING. BUILDING SEAS CAN BE EXPECTED ALONG THE UPPER
TEXAS COAST. CAUTION FLAGS ARE CURRENTLY IN EFFECT...AND ADVISORIES
MIGHT BE NEEDED IF SEAS BUILD HIGHER THAN ANTICIPATED. PERIODS OF
SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ACROSS OUR AREA OVER THE
NEXT COUPLE OF DAYS. TOWARD THE END OF THE WEEK...EXPECT WEAKENING
ONSHORE WINDS AND LOWERING SEAS. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 94 75 95 75 94 / 30 20 20 10 20
HOUSTON (IAH) 93 77 93 76 92 / 40 20 30 10 20
GALVESTON (GLS) 89 81 91 81 90 / 30 20 30 20 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 8 PM CDT THIS EVENING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
627 AM CDT TUE SEP 2 2014
.AVIATION...
/12Z TAFS/
VFR conditions should prevail across most West Central Texas
terminals through the period. However, we are seeing the expected
MVFR stratus developing on low cloud imagery, although remaining
pretty patchy at this point. Suspect that it will expand a little
more through sunrise, and then quickly dissipate. Even at those
locations it does effect, it will be a move in and out quickly
type of feature. Otherwise, gusty south winds through daylight
hours with just a scattered afternoon cu field developing.
&&
.PREV DISCUSSION... /ISSUED 354 AM CDT TUE SEP 2 2014/
SHORT TERM...
(Today and Tonight)
Another mild night ongoing across West Central Texas, with south
winds remaining strong enough to keep temperatures from dropping
very much. Readings still right around 80 degrees at 3 AM (08Z).
Models do indicate that some patchy low cloudiness will develop by
sunrise and spread northward into the area, with low cloud satellite
imagery showing some of this starting to develop across portions of
Central Texas.
Another hot day in store for the area, with the upper level ridge of
high pressure in control. The 00Z NAM showed some convection across
West Central Texas this afternoon, but the GFS is dry. Both the TTU
WRF and the HRRR both show a similar pattern, scattered sea breeze
activity pushing well inland today, but dissipating at sunset across
Central Texas. Thus, will not insert PoPs into the forecast.
After readings above the 100 degree mark at San Angelo and
Abilene, models indicate a slight cooling at 850MB today as a
little cooler and more moist air mass from the Gulf of Mexico
slides into the area. Will keep afternoon highs below the 100
degree mark, but still a degree or two above guidance. Mild again
tonight as south winds keep temperatures from dropping very
quickly. Again, stayed just a little above guidance, as it has
been too cool for the last several days.
LONG TERM...
Surface temperatures fall 2 to 3 degrees F Wednesday as 850 MB
temperatures fall another 1 to 2 degrees Celsius. Tropical Storm
Dolly in the Bay of Campeche is expected to move into Mexico
early Wednesday, and may send weak disturbances/moisture
northward to affect the I-10 corridor Thursday and Friday. This
is indicated mainly by the EC model, as the GFS model is dry and
the NAM model nearly so. Will keep rain chances out of forecast
for this time period, given the uncertainty and limited agreement
in the models.
For Saturday night into Sunday, however, both the GFS and EC
modes are still indicating a weak cold front to bring a slight
chance of showers and thunderstorms. Forecast already has rain
chances in for this time period, and will maintain them.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 100 76 96 74 95 / 5 5 5 5 5
San Angelo 98 75 95 74 94 / 5 5 10 10 10
Junction 95 77 93 74 93 / 10 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
CONTINUE ON WITH THE FORECAST DISCUSSION...
IN A BASIC SENSE...THE MOVEMENT OF THUNDERSTORM SYSTEMS IS
CONTROLLED BY THE AVERAGE OF THE WINDS ALOFT...OFTEN REFERRED TO
AS THE STEERING WINDS. IN MOST CASES...THUNDERSTORMS WILL SIMPLY
MOVE IN THE DIRECTION IN WHICH THE WINDS ALOFT ARE BLOWING.
HOWEVER THE SECOND COMPONENT TO CONSIDER IS OFTEN REFERRED TO AS
THE PROPAGATION COMPONENT OF STORM MOTION. PROPAGATION INFLUENCES
STORM MOTION BY CHANGING THE DIRECTION OF MOTION OF A THUNDERSTORM
SYSTEM IN THE DIRECTION THAT NEW THUNDERSTORMS DEVELOP. THIS IS
THE MORE COMPLICATED FACTOR TO UNDERSTAND...BUT IN GENERAL...NEW
THUNDERSTORMS TEND TO DEVELOP IN THE OPPOSITE DIRECTION OF THE LOW
LEVEL JET. ON A DAY LIKE TODAY...WHERE THE STEERING WINDS ARE
SOMEWHAT LIGHT DUE TO UPPER LEVEL RIDGING OVER TEXAS...BUT THE
LOW-LEVEL JET IS RELATIVELY STRONG...THE PROPAGATION COMPONENT CAN
DOMINATE THE DIRECTION IN WHICH THE THUNDERSTORM SYSTEM MOVES. FOR
TODAY...THE STEERING WINDS ARE SOMEWHAT LIGHT AND WOULD INDICATE
AN EASTERLY STORM MOTION. THIS IS WHY THE STORMS ARE JUST SORT OF
SITTING THERE ALONG THE FRONT AS OF 3 AM. HOWEVER IF THIS RESULTS
IN A STRONG ENOUGH COLD POOL (A COLLECTION OF RAIN COOLED AIR)
THIS COLD POOL COULD START TO SURGE SOUTH...CAUSING NEW STORMS TO
DEVELOP IN THE OPPOSITE DIRECTION OF THE LOW-LEVEL JET. SINCE THE
LOW-LEVEL JET EXTENDS FROM OUR CWA TO THE FRONT...THE WHOLE
COMPLEX OF STORMS COULD START TO MOVE SOUTH DIRECTLY TOWARDS THE
RED RIVER...BUT WILL STILL MOVE AT LEAST SLIGHTLY TO THE EAST DUE
TO THE STEERING WINDS ALOFT. THIS IS A DRAMATIC SHIFT IN DIRECTION
FROM WHAT STORMS HAVE BEEN DOING OVERNIGHT...BUT IT MAKES SENSE IN
THE CONTEXT OF WHAT WAS DESCRIBED ABOVE.
THE MAIN POINT OF UNCERTAINTY THIS MORNING IS: WILL
THUNDERSTORMS BECOME ORGANIZED ENOUGH TO MOVE AS A SYSTEM?
THAT IS LARGELY UNKNOWN BECAUSE JUST LOOKING AT THE STORMS ON
RADAR IS NOT ENOUGH TO DETERMINE HOW STRONG THE COLD POOL WILL
GET...BUT THE FACT THAT THE HRRR AND THE TEXAS TECH WRF BOTH
ADVERTISE A DRAMATIC SHIFT TO THE SOUTH OF THUNDERSTORMS TOWARDS
THE RED RIVER AROUND SUNRISE GIVES CONFIDENCE IN THIS SOLUTION.
WENT AHEAD AND PLACED A VERY SMALL AREA OF 20 POPS IN THE FORECAST
FROM JUST NORTH OF SHERMAN EXTENDING TO THE SOUTHEAST INCLUDING
MUCH OF LAMAR COUNTY. IF THE STORMS DO MOVE TO THE SOUTH AS THESE
HIGH RESOLUTION MODELS INDICATE...THEY WILL BE IN THEIR
DISSIPATING STAGES BY THE TIME THEY CROSS THE RED RIVER WELL
AFTER SUNRISE THIS MORNING...SO NO STRONG OR SEVERE WEATHER IS
EXPECTED AT THIS TIME.
THIS AFTERNOON...MODELS CONTINUE TO CONSISTENTLY SHOW A SURGE OF
TROPICAL MOISTURE TO THE NORTHWEST FROM THE TX GULF COAST THIS
AFTERNOON. THIS SURGE OF MOISTURE APPEARS TO BE ASSOCIATED WITH A
SUBTLE BUT IMPORTANT MID-LEVEL WIND SHIFT ASSOCIATED WITH DOLLY
MOVING NORTHWEST TOWARDS THE NORTHERN MEXICO GULF COAST. THIS
DEEPER TROPICAL MOISTURE IS EXPECTED TO REMAIN SOUTH OF THE
INTERSTATE 20 CORRIDOR THIS AFTERNOON...SO REORIENTED POPS A BIT
TO HIGHLIGHT THE SOUTHERN HALF OF THE CWA. IN GENERAL...THERE IS
STILL NO OBVIOUS LIFT...SO THE COVERAGE OF STORMS WILL PROBABLY BE
ISOLATED IN NATURE...AND LEFT POPS AT THE 20 PERCENT LEVEL FOR NOW.
WEDNESDAY THROUGH FRIDAY...DOLLY IS EXPECTED TO MAKE LANDFALL OVER
NORTHERN MEXICO LATE THIS EVENING...AND THEN CONTINUE OFF TO THE
WEST-NORTHWEST THROUGH THE END OF THE WEEK. MODELS SEEM TO SEND
THE DEEPER MID-LEVEL TROPICAL MOISTURE PLUME TO THE WEST WITH
DOLLY...SO WENT AHEAD AND REMOVED POPS FROM THE FORECAST ON
WEDNESDAY AFTERNOON ACROSS THE SOUTHERN CWA AND LEFT THE REMAINDER
OF THE FORECAST DRY. WEAK UPPER LEVEL RIDGING IS THE DOMINANT
FEATURE DURING THIS TIME FRAME...SO EXPECT SUBSIDENCE TO WIN OUT
IN KEEPING THINGS DRY ACROSS NORTH AND CENTRAL TEXAS.
THIS WEEKEND...MODELS CONTINUE TO HINT AT A COLD FRONT MOVING
SOUTH OF THE RED RIVER SOMETIME SATURDAY AFTERNOON THROUGH SUNDAY
MORNING. MODELS STILL SEEM TO INDICATE THAT THE PRIMARY REASON
THAT THE FRONT MAKES IT SOUTH OF THE RED RIVER IS DUE TO
PERSISTENT THUNDERSTORM ACTIVITY ALONG THE FRONT LATE THIS WEEK.
IF THE FRONTAL MOTION IS REALLY DEPENDENT UPON PERSISTENT
THUNDERSTORM ACTIVITY...CONFIDENCE IN THE TIMING AND PLACEMENT OF
THE FRONT IS GOING TO REMAIN LOW UNTIL LATE THIS WEEK.
THE BIGGEST REASON FOR OPTIMISM IN THE FRONT MAKING IT THIS FAR
SOUTH IS OBSERVING WHAT HAPPENS TODAY. IF MCS ACTIVITY FROM THE
OK/KS BORDER ACTUALLY SURGES SOUTH THIS MORNING...IT BECOMES EASY
TO SEE HOW PERSISTENT STORMS TO OUR NORTH CAN SEND A STRONG
OUTFLOW BOUNDARY/FRONT ACROSS NORTH TEXAS UNDER WEAK RIDGING
ALOFT. THE FRONT IS MOST LIKELY TO BE IN PLACE OVER THE CWA ON
SUNDAY...SO LEFT POPS MAINLY ALONG AND NORTH OF INTERSTATE 20 ON
SATURDAY...AND KEPT THEM BROAD BRUSHED OVER THE ENTIRE CWA ON
SUNDAY.
EARLY NEXT WEEK...THE FRONT...ASSUMING IT MAKES IT HERE THIS
WEEKEND...WILL PROBABLY DISSIPATE BY MONDAY. BECAUSE THE FRONT
DOES NOT REPRESENT A TRUE AIRMASS REPLACEMENT...THAT IS...THERE IS
NO CANADIAN/OR SIGNIFICANTLY COOL AIR TO THE NORTH OF THIS
FRONT...IT WILL UNDERGO FRONTOLYSIS AND LOSE DEFINITION QUICKLY
UNDER RIDGING ALOFT. LEFT THE FORECAST FOR EARLY NEXT WEEK DRY AS
A RESULT.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 97 77 96 77 96 / 5 5 5 5 0
WACO, TX 98 75 97 74 97 / 20 20 10 5 5
PARIS, TX 92 72 91 72 92 / 20 10 5 5 0
DENTON, TX 96 75 95 74 95 / 10 5 5 0 0
MCKINNEY, TX 95 74 94 74 94 / 10 5 5 5 0
DALLAS, TX 97 78 96 78 96 / 5 5 5 5 0
TERRELL, TX 96 76 96 75 96 / 10 10 5 5 0
CORSICANA, TX 97 76 96 75 96 / 20 20 10 5 5
TEMPLE, TX 98 72 97 73 97 / 20 20 10 5 5
MINERAL WELLS, TX 97 73 96 72 96 / 5 5 5 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/69
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
309 PM MDT TUE SEP 2 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT TUE SEP 2 2014
ALL IS QUIET ON THE WESTERN FRONT THIS AFTERNOON. A BIT OF CUMULUS
HAS DEVELOPED OVER THE HIGH COUNTRY ABOUT AS EXPECTED WHICH SHOULD
DISSIPATE WITH THE SETTING SUN. LITTLE IN THE WAY OF QUASI-
GEOSTROPHIC DYNAMICS EXPECTED THROUGH THE PERIOD. PRECIPITABLE
WATER VALUES ARE FORECAST TO BE A BIT HIGHER TOMORROW THAN IS THE
CASE TODAY BUT STILL NOTHING TO GET EXCITED ABOUT...MAYBE SOME
MORE CUMULUS THAN TODAY. THE CIRA WRF SIMULATED SATELLITE IMAGERY
DEPICTS SOME STRATUS OVER LINCOLN COUNTY AND ITS ENVIRONS AROUND
SUNRISE WEDNESDAY...SIMILAR TO TODAY...AND HAVE INCLUDED THIS IN
THE GRIDS.
THE MAIN ISSUE FOR TOMORROW IS AN INCREASE IN THE WINDS AND THE
ABOVE NORMAL HIGH TEMPERATURES DUE TO INCREASING PRESSURE
GRADIENTS AND DOWNSLOPE COMPONENT. BEASTLY 90+ READINGS ARE
EXPECTED AT LOWER ELEVATIONS WITH ABOVE NORMAL MAXIMA IN THE HIGH
COUNTRY AS WELL. OFFICIAL RECORD HIGH OF 95 AT DIA SET IN 1995
COULD BE THREATENED. LOW HUMIDITIES IN AND CLOSE TO THE MOUNTAINS
WILL COMBINE WITH THE WINDS TO ELEVATE THE FIRE DANGER ESPECIALLY
IN SOUTH PARK. NO PLANS FOR FIRE WEATHER HIGHLIGHTS AT THIS TIME.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 308 PM MDT TUE SEP 2 2014
DRY WEATHER WILL REMAIN IN PLACE THROUGH WEDNESDAY NIGHT AND MOST
OF THURSDAY. BY LATE THURSDAY...MID/UPPER LEVEL MOISTURE BEGINS
TO INCREASE IN/NEAR THE MOUNTAINS BY LATE IN THE DAY. THE LOW
LEVELS ARE QUITE STABLE SO ANY CONVECTIVE SHOWERS/STORMS THAT
DEVELOP IN THE HIGH COUNTRY WILL LIKELY DISSIPATE AS THEY ATTEMPT
TO MOVE INTO THE LOWER ELEVATIONS OF THE PLAINS. HAVE TRIMMED BACK
THE EASTERN EXTENT OF THE ALREADY LOW POPS...BUT SOME FURTHER
REFINEMENT COULD BE NECESSARY TO REMOVE THEM FROM THE I-25
CORRIDOR AS WELL. FOR NOW...HAVE KEPT LOW POPS IN CONSIDERING OUR
PROXIMITY TO THE RIGHT REAR ENTRANCE REGION OF DEPARTING UPPER
LEVEL SPEED MAX.
ON FRIDAY AND SATURDAY...SURFACE HIGH PRESSURE BUILDS OVER THE
CENTRAL PLAINS. THIS WILL KEEP A RELATIVELY COOL AND SLIGHTLY
STABLE AIRMASS ACROSS MOST OF THE COLORADO PLAINS. AT THE SAME
TIME...THERE IS A MODEST THETA-E RIDGE BUILDING ALONG THE FRONT
RANGE AND OVER THE MOUNTAINS...WHICH SHOULD BRING SCATTERED
SHOWER/STORM DEVELOPMENT EACH AFTERNOON AND EVENING. WOULD EXPECT
A FEW OF THESE TO DRIFT ONTO THE PLAINS EACH LATE
AFTERNOON/EVENING AS WELL...WITH A WEAKER CAP AND AGAIN THE CLOSE
PROXIMITY OF THE UPPER LEVEL SPEED MAX. TEMPERATURES SHOULD REMAIN
A FEW DEGREES BELOW NORMAL ON THE PLAINS WITH THE COOLER HIGH
PRESSURE AND LIGHT EASTERLY UPSLOPE FLOW ACROSS THE HIGH PLAINS.
ON SUNDAY...WEAK LEE TROUGHING WILL LIKELY DEVELOP AS CENTRAL
PLAINS HIGH PRESSURE RETREATS TO THE EAST. THIS SHOULD ALLOW
TEMPERATURES TO REBOUND TO NEAR NORMAL TEMPERATURES. CAPES MAY
ALSO INCREASE WITH SOUTHERLY LOW LEVEL FLOW AND INCREASED LOW
LEVEL MOISTURE...RESULTING IN A FEW STRONGER STORMS. OVERALL...
THE FORECAST AREA REMAINS ON THE NORTHERN EDGE OF ANY DEEPER
MONSOONAL MOISTURE SO THE THREAT OF ANY HEAVY RAINFALL IS LOW
DUE TO EXPECTED FASTER STORM MOTIONS AND LIMITED PRECIPITABLE
WATER.
BY LATE MONDAY OR TUESDAY...WE SEE SOME POTENTIAL FOR DRYING WITH
A LARGER TROUGH MOVING IN FROM THE PACIFIC NORTHWEST. THIS WOULD
SWEEP ANY DEEPER MOISTURE TO THE EAST AND LOWER THE CHANCE OF ANY
SHOWERS/STORMS. TIMING IS SOMEWHAT UNCERTAIN HERE WITH THE LATEST
12Z ECMWF SHOWING A SLOWER EASTWARD ADVANCEMENT OF THIS TROUGH.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z WEDNESDAY LATE AFTERNOON)
ISSUED AT 308 PM MDT TUE SEP 2 2014
CAVOK THROUGH WEDNESDAY. A WEAK WESTERLY PUSH SWUNG THE WINDS
AROUND TO WESTERLY AT KDEN. THE FEATURE SHOWS UP ON THE DOPPLER
VELOCITY BUT IT IS NOT CLEAR WHAT IT IS. THE HRRR HAS A HINT OF IT
BUT IT WASHES OUT LATER THIS AFTERNOON WITH EAST SOUTHEASTERLIES
REFORMING. THE OTHER TWO TERMINALS WERE LESS IMPACTED BY THIS.
DRAINAGE FLOW EXPECTED TO FORM OVERNIGHT WHICH MAY BE A ENHANCED
JUST A BIT LATE TONIGHT AS LOW PRESSURE DEVELOPS TO OUR NORTHEAST.
EXPECTING GENERALLY LIGHT FLOW TOMORROW WHICH SHOULD FAVOR A
SOUTHWESTERLY DIRECTION.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...ET
LONG TERM...BARJENBRUCH
AVIATION...ET
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
332 PM EDT TUE SEP 2 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION TONIGHT. HIGH PRESSURE WILL BUILD
INTO THE AREA FROM THE WEST AND PERSIST THROUGH FRIDAY. ANOTHER COLD
FRONT WILL CROSS THE REGION ON SATURDAY AND THEN STALL TO THE SOUTH
OF OUR AREA. HIGH PRESSURE WILL BUILD ACROSS THE GREAT LAKES REGION
AND THEN SLIDE ACROSS TO THE NORTH OF THE REGION EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
FRONT IS JUST NOW MOVING OFF THE GREAT LAKES INTO FAR WESTERN PA. DO
NOT EXPECT IT TO MAKE ITS ARRIVAL MUCH BEFORE 06Z. HIGH RES MODELS
LIKE THE HRRR HAVE BEEN CONSISTENT IN SHOWING A LINE OF CONVECTION
MOVING IN AHEAD OF THE FRONT LATE THIS EVENING. HOWEVER, BY THAT
TIME, INSTABILITY SHOULD BE WANING AND THERE COULD BE A SMALL
BOUNDARY LAYER INVERSION. THUS, THE LINE SHOULD BE DISSIPATING AS IT
MOVES THROUGH THE REGION. PWATS ARE STILL WELL ABOVE NORMAL, SO
LOCALIZED HEAVY RAIN WILL BE POSSIBLE. WHILE THE HIGHEST SHEAR
VALUES SHOULD REMAIN NW OF OUR REGION, COULD SEE A FEW STRONG WINDS
GUSTS WHEN THE FRONT INITIALLY ARRIVES IN SOUTHEAST PA BUT THAT
THREAT SHOULD BE SHORT LIVED AS WE TRANSITION FROM SURFACE BASED TO
ELEVATED INSTABILITY.
GIVEN THE VERY LATE ARRIVAL OF THE COLD FRONT, AND THE FACT THAT THE
TEMPERATURE GRADIENT ACROSS THE FRONT IS RATHER SMALL, MINS TONIGHT
SHOULD NOT BE TOO MUCH LOWER THAN THEY WERE THIS MORNING.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
AS MENTIONED PREVIOUSLY, THERE WON`T BE A LARGE DIFFERENCE IN THE
TEMPERATURES POST FRONTAL (HIGHS WILL GENERALLY BE IN THE 80S ACROSS
THE REGION). HOWEVER, WHAT THE FRONT WILL BE BRINGING IS CONSIDERABLE DRY
AIR ADVECTION. DEW POINTS INTO THE UPPER 50S AND LOWER 60S ACROSS
THE REGION BY TOMORROW AFTERNOON. THUS, WHILE HEAT INDEX VALUES HAVE
BEEN ABOUT 5 DEGREES ABOVE AIR TEMPERATURE TODAY, BY TOMORROW, HEAT
INDEX VALUES WILL BE RIGHT AT THE AIR TEMPERATURES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
WEDNESDAY NIGHT THROUGH FRIDAY...HIGH PRESSURE DOMINATES OUR WEATHER
THROUGH THE END OF THE WEEK AS IT SHIFTS JUST TO TOUR SOUTH AND EAST
LATE WEDNESDAY THROUGH FRIDAY. THIS WILL KEEP US IN A MORE SOUTH TO
SOUTHWESTERLY FLOW AND IN RETURN WE WILL CONTINUE TO SEE AN INCREASE
IN MOISTURE ACROSS THE REGION. TEMPERATURES WILL CONTINUE TO MIMIC
MORE OF MID SUMMER AS OPPOSED TO LATE SUMMER AND WE WILL SEE MAX
TEMPS REACH INTO THE UPPER 80S TO AROUND 90 ON BOTH THURSDAY AND
FRIDAY.
SATURDAY...THE HIGH SHIFTS FURTHER OFFSHORE AND WE WILL BE AWAITING
THE PASSAGE OF A COLD FRONT THROUGH THE DAY. THE FRONT APPEARS TO BE
SLOW MOVING AND MAY TAKE ALL DAY TO CROSS FROM THE NORTHWESTERN
PORTIONS OF THE AREA AND THEN THROUGH THE SOUTHERN MOST POINTS. WE
WILL LIKELY SEE A PRE-FRONTAL TROUGH DEVELOP ACROSS THE AREA AND
THIS WILL LIKELY HELP SERVE AS A FOCUS FOR ANY PRE-FRONTAL
CONVECTION AND SHOWERS. SATURDAY WILL BE THE LAST DAY OF THIS HEAT
WAVE AS COOLER AIR BEHIND THE FRONT WILL DROP TEMPS QUITE A BIT.
SUNDAY...THE FRONT IS SLOW ENOUGH THAT WE MAY NOT SEE IT CLEAR THE
DELMARVA AREA UNTIL SUNDAY MORNING. AS THE FRONT PUSHES SOUTH, THE
QUESTION WILL BE, WHERE WILL THE FRONT STALL? CURRENT MODEL GUIDANCE
INDICATES THAT THE FRONT WILL HAVE ENOUGH OF A PUSH TO GET SOUTH OF
OUR AREA, WHICH SHOULD ALLOW FOR SOME COOLER AND DRIER AIR TO
INFILTRATE OUR REGION. THE SLOW NATURE OF THE FRONT WILL ALLOW FOR
SHOWERS TO CONTINUE, ESPECIALLY FURTHER SOUTH, INTO SUNDAY. AS THE
FRONT PUSHES FURTHER SOUTH, ANY LINGERING SHOWERS SHOULD END FROM
NORTH TO SOUTH. WITH HIGH PRESSURE BUILDING INTO THE GREAT LAKES
AREA AND THE STALLED BOUNDARY TO OUR SOUTH, WE WILL BE IN A MORE
EASTERLY FLOW REGIME WITH MOSTLY CLOUDY SKIES. THIS WILL ALLOW US TO
BE COOLER ACROSS THE AREA. TEMPERATURES WILL ONLY MAKE IT INTO THE
70S THROUGH THE REGION AND IT WILL TRULY FEEL LIKE FALL OUT THERE.
MONDAY THROUGH TUESDAY...THE BOUNDARY REMAINS STALLED TO OUR SOUTH
BUT AS WE HEAD INTO MONDAY, A WAVE DEVELOPS ALONG IT AND IT STARTS
TO MOVE A BIT. IT CURRENTLY LOOKS LIKE THE WAVE HELPS MOVE THE
FRONT SLIGHTLY NORTH AND THEN TO THE EAST, KEEPING THE MAIN
BOUNDARY TO OUR SOUTH. COOLER TEMPERATURES WILL CONTINUE ON MONDAY
AND TUESDAY WITH HIGHS INTO THE MID TO UPPER 70S, WITH SOME LOWER
80S POSSIBLE AS SKIES CLEAR OUT AND WE START TO SEE MORE SUNSHINE.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
ISOLATED TSRA WILL BE POSSIBLE THROUGH 00Z THIS EVENING.
HOWEVER, THINK THE BULK OF THE THUNDERSTORM ACTIVITY SHOULD REMAIN
WEST OF THE REGION. THE COVERAGE THROUGH THIS TIME IS TOO LIMITED
TO MENTION IN MOST OF THE TAFS FOR NOW. STARTING AROUND 00Z, WE
SHOULD SEE A LINE OF SHRA AND TSRA MOVE INTO THE REGION FROM THE
WEST. HIGH RESOLUTION MODELS HAVE BEEN CONSISTENT IN SHOWING THIS
GENERAL PATTERN AND TIMING. HOWEVER, THERE IS SOME QUESTION OF THE
SOUTHERN EXTENT OF THE LINE (WHICH MAY NOT GO SOUTH OF PHL), AND IF
THE LINE WILL START TO SCT BEFORE IT REACHES THE DELAWARE RIVER
VALLEY. THEREFORE HAVE INCLUDED A TEMPO FOR THE SE PA SITES (KRDG
AND KABE) AND KTTN WHERE THERE IS HIGHER CONFIDENCE, BUT ONLY HAVE
MENTION OF VCSH FOR MOST OF THE REST OF THE SITES.
ONCE THE FRONT MOVES THROUGH AFTER 06Z, EXPECT NORTHWESTERLY WINDS
AND GENERALLY VFR CONDITIONS. THERE IS A SMALL RISK OF BR
DEVELOPMENT BUT WITH DRY AIR ADVECTION BEHIND THE FRONT, THINK THIS
IS UNLIKELY.
OUTLOOK...
WEDNESDAY NIGHT THROUGH FRIDAY... MAINLY VFR CONDITIONS EXPECTED.
SOME FOG IS POSSIBLE WHICH MAY CAUSE MVFR/IFR CONDITIONS ON THU
AND FRI MORNINGS.
SATURDAY THROUGH SUNDAY...MAINLY VFR CONDITIONS EXPECTED WITH
MVFR/IFR CONDITIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA
THROUGH TOMORROW. GUSTY WINDS WILL BE POSSIBLE IN THE VICINITY OF
ANY THUNDERSTORMS THIS AFTERNOON AND TONIGHT. AN ABRUPT WIND SHIFT
TO NORTHWESTERLY WINDS IS EXPECTED WITH A COLD FRONT THAT WILL MOVE
THROUGH LATE TONIGHT. HOWEVER, WIND GUSTS SHOULD REMAIN WELL BELOW
20KT EVEN WITH THE FRONT.
OUTLOOK...
WEDNESDAY NIGHT THROUGH SUNDAY...SUB-ADVISORY CONDITIONS ARE
EXPECTED. SOME STRONGER GUSTS AND HIGHER WAVES ARE POSSIBLE IN
SHOWERS AND THUNDERSTORMS, MAINLY IN THE SATURDAY/SUNDAY TIMEFRAME.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MEOLA
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...MEOLA
AVIATION...JOHNSON/MEOLA
MARINE...JOHNSON/MEOLA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
400 PM EDT TUE SEP 2 2014
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOW THE MAIN NORTHERN STREAM
FLOW FAR TO OUR NORTH ALONG THE CANADIAN BORDER AND OVER TOP AN
ELONGATED WEST TO EAST ORIENTED UPPER RIDGE EXTENDING ACROSS THE
SOUTHERN TIER OF THE CONUS. OUR FORECAST AREA RESIDES UNDER THIS
LARGE UPPER RIDGE...HOWEVER A TUTT FEATURE RETROGRADING WESTWARD
OVER THE BAHAMAS IS BEGINNING TO ERODE THE RIDGE TO OUR SOUTH
AND EAST...AND WILL BEGIN TO BREAK DOWN THE RIDGE OVER OUR HEADS
TONIGHT.
02/12Z SOUNDING PROFILE SHOWS THE INFLUENCE OF THE UPPER RIDGE
OVERHEAD WITH A SUBSIDENCE INVERSION SIGNATURE AROUND 750MB. ABOVE
THIS LAYER IT ON THE DRY SIDE. THE RESULTING PW IS LOW AROUND
1.7"...WHICH IS BELOW AVERAGE FOR EARLY SEPTEMBER...BUT NOT AN
EXTREME VALUE. WE HAVE SEEN A BIT OF COOLING IN THE MID-LEVELS SINCE
MONDAY...POSSIBLY THE VERY BEGINNING INFLUENCE OF THE APPROACHING
TUTT. WILL EXPECT TO SEE ANOTHER DEGREE OR 2 OF COOLING IN THE
MID-LEVELS OVER THE NEXT 24 HOURS AS THE TUTT PASSES JUST TO OUR
SOUTH. THIS COOLING ALONG WITH OUR EVENTUAL POSITION ON THE EASTERN
PERIPHERY OF THE TUTT (FAVORED FOR UPWARD MOTION AND CONVECTION) MAY
LEAD TO ENHANCED CONVECTION LATER IN THE WEEK.
SEA-BREEZE HAS MOVED INLAND TO AROUND I-75 FROM TAMPA BAY SOUTHWARD
PER OBS AND RADAR ANALYSIS...BUT APPEARS TO BE PINNED VERY NEAR THE
COAST UP ALONG THE NATURE COAST. THE 10 KNOTS OF EASTERLY FLOW JUST
ABOVE THE SURFACE WILL KEEP THE INLAND PENETRATION SLOW THE NEXT FEW
HOURS BEFORE THE EAST COAST SEA-BREEZE / CONVECTIVE OUTFLOWS COLLIDE
WITH IT DURING THE EARLY EVENING. HAVE SEEN SOME SCT STORMS ALREADY
FORM OVER THIS BOUNDARY AND DRIFT WESTWARD INTO THE POST SEA-BREEZE
ENVIRONMENT. THIS IS UNLIKE YESTERDAY WHEN VERY LITTLE OCCURRED
UNTIL THE MAIN COLLISION AND ALLOWED THE RELEASE OF ALL THE DAYS
INSTABILITY. THEREFORE...THE POTENTIAL FOR EXPLOSIVE THUNDERSTORMS
DEVELOPMENT THIS EVENING IS LOWER...BUT WILL STILL NEED TO BE
WATCHED CLOSELY. ACROSS THE FAR SOUTHERN ZONES THE SHOWERS AND
STORMS ARE FILLING IN AND RAIN CHANCES LOOKING QUITE LIKELY TO THE
SOUTH OF SARASOTA OVER THE NEXT SEVERAL HOURS.
STORM MOTION WILL BE WESTWARD AFTER INITIATION...SO MARINERS SHOULD
CONTINUE TO BE AWARE OF THE WEATHER OVER LAND TO THEIR EAST AND BE
PREPARED FOR STORMS TO RAPIDLY DEVELOP AND MOVE OFFSHORE.
&&
.SHORT TERM (TONIGHT AND WEDNESDAY)...
TONIGHT...
THE ACTIVITY WILL ALL PUSH OFFSHORE WITHIN A COUPLE HOURS OF SUNSET
AND PROVIDE THE REGION WITH A MOSTLY DRY AND SEASONABLE OVERNIGHT
PERIOD. CAN NOT RULE OUT A FEW ISOLATED SHOWERS LATER TONIGHT
ROTATING IN FROM THE EAST OVER CHARLOTTE/LEE COUNTY AS THE INFLUENCE
OF THE TUTT INCREASES...BUT IMPACT SHOULD BE MINIMAL AND WILL LEAVE
MENTION OUT OF THE FORECAST FOR NOW.
WEDNESDAY...
TUTT CELL MOVES OVER THE FLORIDA STRAITS AND SOUTH FLORIDA ENDING
THE DOMINATION OF THE UPPER RIDGE ON THE FLORIDA PENINSULA. AT THE
LOWER LEVELS THOUGH...WILL STILL BE DEALING WITH A LIGHT/MODERATE
EASTERLY FLOW REGIME. THE MORNING HOURS WILL BE GENERALLY QUIET AND
DRY IN TERMS OF WEATHER...BUT WE ARE LIKELY TO SEE CONVECTIVE
INITIATION A BIT EARLIER THAN HAS BEEN THE CASE OVER RECENT DAYS AS
THE LOSS OF LARGE SCALE SUBSIDENCE WILL PROMOTE A LOWER CONVECTIVE
TEMPERATURE. WITH THE EARLIER INITIATION...THE PATTERN OF CONVECTION
BECOME LESS EASY TO PUT DETAIL INTO AS THERE IS MORE TIME FOR
NUMEROUS OUTFLOW BOUNDARIES TO DISRUPT THE LARGE SCALE FLOW.
THEREFORE WILL KEEP HIGH END CHANCE 40-55% RAIN CHANCES IN AT MOST
LOCATIONS...BUT WITH THE EASTERLY FLOW REGIME...WILL KEEP A TENDENCY
FOR THE HIGHER RAIN CHANCES TO MIGRATE TOWARD THE WEST COAST WITH
TIME DURING THE AFTERNOON AND EARLY EVENING.
&&
.LONG TERM (WEDNESDAY NIGHT-TUESDAY)...
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH THE
LONG TERM PERIODS. AN UPPER LEVEL TROUGH AND INCREASING DEEP
LAYER MOISTURE WILL SPREAD NORTHWESTWARD ACROSS THE STATE ON
THURSDAY AND FRIDAY...WITH WEAK UPPER LEVEL RIDGING THEN BUILDING
INTO THE AREA OVER THE WEEKEND AND INTO EARLY NEXT WEEK. AT THE
SURFACE...THE SUBTROPICAL RIDGE AXIS IS EXPECTED TO REMAIN NORTH
OF THE FORECAST AREA THROUGH THE END OF THE WORK WEEK...WITH MODEL
SOLUTIONS THEN SHOWING SOME DISAGREEMENT IN POSITIONING DETAILS
OVER THE WEEKEND AND INTO EARLY NEXT WEEK. THE GFS AND CANADIAN
SHOW THE RIDGE AXIS REMAINING NORTH OF THE FORECAST AREA...BUT THE
ECMWF SHOWS IT SHIFTING SOUTHWARD INTO CENTRAL FLORIDA.
OVERALL...TYPICAL SUMMERTIME WEATHER IS EXPECTED TO PREVAIL WITH
SCATTERED TO NUMEROUS MAINLY AFTERNOON/EVENING SHOWERS AND
THUNDERSTORMS EXPECTED EACH DAY. HIGH TEMPERATURES WILL REMAIN CLOSE
TO NORMAL THROUGH THE LONG TERM PERIOD.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION LATE THIS MORNING.
BEGINNING TO SEE THE FIRST OF A CU FIELD BEGIN TO DEVELOP. SCT
SHOWERS AND STORMS WILL BE MOVING EAST TO WEST ACROSS THE PENINSULA
DURING THE AFTERNOON. KFMY/KRSW/KPGD WILL BE FIRST TO SEE THE STORMS
IN THE VICINITY BY MID AFTERNOON. FURTHER NORTH AROUND THE TAMPA BAY
TERMINALS STORMS ARE LIKELY TO BE LATER IN THE AFTERNOON AND EVENING
HOURS. AWAY FROM ANY STORMS...VFR CONDITIONS WILL PREVAIL THROUGH
THE TAF PERIOD.
&&
.MARINE...
EAST SOUTHEAST WINDS LESS THAN 15 KNOTS AND SEAS 2 FEET OF LESS
WILL CONTINUE INTO NEXT WEEK AS HIGH PRESSURE OVER THE ATLANTIC
PUSHES WEST OVER THE FLORIDA PENINSULA. THE SEA BREEZE WILL SET UP
ALONG AND NEAR THE COAST EACH DAY ALLOWING FOR AN ONSHORE FLOW FROM
THE SOUTHWEST TO NORTHWEST DIRECTION. SCATTERED SHOWERS AND STORMS
WILL BE POSSIBLE EACH DAY DEVELOPING OVER LAND AND THEN PUSHING
WESTWARD OVER THE COASTAL WATERS DURING THE EVENING HOURS. THE ONLY
EXPECTED HAZARD WILL BE GUSTY WINDS AND HIGHER SEAS IN THE VICINITY
OF THUNDERSTORMS.
&&
.FIRE WEATHER...
A RIDGE OF HIGH PRESSURE WILL REMAIN NORTH OF THE REGION FOR THE
NEXT SEVERAL DAYS. THIS WILL RESULT IN EASTERLY WINDS WITH THE
HIGHEST RAIN CHANCES ALONG THE I-75 EACH AFTERNOON. OTHER THAN THE
DAILY STORMS...NO SIGNIFICANT FIRE WEATHER CONCERNS ARE EXPECTED.
FOG POTENTIAL...PATCHY GROUND FOG COULD DEVELOP LATE EACH
NIGHT...ESPECIALLY IN LOCATIONS THAT RECEIVE RAIN DURING THE
PREVIOUS EVENING. HOWEVER...NO SIGNIFICANT FOG IS ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 76 90 76 91 / 30 50 30 60
FMY 75 92 74 91 / 10 50 10 60
GIF 74 92 74 92 / 10 50 10 50
SRQ 74 92 73 91 / 30 40 30 60
BKV 71 91 71 92 / 20 50 30 60
SPG 79 91 78 90 / 30 40 30 60
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/FIRE WX...MROCZKA
MARINE...MCKAUGHAN
LONG TERM...JELSEMA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
346 PM EDT TUE SEP 2 2014
.SYNOPSIS...
ISSUED AT 1051 AM EDT TUE SEP 2 2014
ISOLATED SHOWERS WILL CONTINUE THROUGH AFTERNOON BEFORE
DIMINISHING AS HIGH PRESSURE SETTLES OVER THE REGION. CLOUD COVER
WILL ALSO DIMINISH THROUGH THE AFTERNOON...ALLOWING HIGH
TEMPERATURES TO CLIMB INTO THE UPPER 70S AND LOW 80S. EXPECT A
QUIET NIGHT...WITH MOSTLY CLEAR SKIES AND LOWS IN THE 50S. AREAS
OF FOG WILL DEVELOP TOWARDS WEDNESDAY MORNING...BECOMING LOCALLY
DENSE AT TIMES.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 344 PM EDT TUE SEP 2 2014
INFILTRATION OF DRIER AIR INTO THE REGION HAS BEEN SLOW THIS
AFTERNOON...WITH AMPLE BOUNDARY LAYER MOISTURE AMID WASHED OUT
SURFACE BOUNDARY ACROSS THE FORECAST AREA. LOW CLOUDS HAVE BEEN SLOW
TO MIX OUT THROUGH EARLY AFTERNOON BUT LATEST SAT TRENDS SHOWING
MORE SCT LOW LVL CLOUD LAYER...ESPECIALLY NW. ISOLD SHOWERS
CURRENTLY NOTED ON RADAR ACROSS NW/NC IN...GIVEN AMPLE BOUNDARY
LAYER MOISTURE...WEAK SFC CONVERGENCE AND SFC HEATING YIELDING VERY
MODEST SB CAPES UP TO 1000 J/KG ACROSS THE REGION. HRRR AND EVEN
NAM12 HINTING AT ISOLD SHOWER ACTIVITY SPREADING EAST ACROSS THE
FORECAST AREA THROUGH SUNSET. THEREFORE HAVE KEPT AN ISOLD SHOWER
MENTION THROUGH 00Z IN THE FCST. LOW CONFIDENCE FOR THUNDER AT THIS
TIME GIVEN LACK OF FORCING AND WEAK MID LVL LAPSE RATES.
AS RIDGING BUILDS EASTWARD INTO THE OVERNIGHT HOURS...CLEARING SKIES
AND DRY CONDITIONS EXPECTED. WITH SLACKENING GRADIENT AND LOW LVL
MOISTURE...ESPECIALLY SE W/ THE PRECIP OVER THE PAST 24 HRS...FOG
DEVELOPMENT LOOKS LIKELY LATE IN THE OVERNIGHT INTO DAYBREAK
WEDNESDAY. KEPT PREVIOUS FCST IN TACT WITH AREAS OF FOG MENTION FROM
09-12Z. LOW CONFIDENCE WITH THE POSSIBILITY OF DENSE FOG AT THIS
TIME...GIVEN LOW LEVEL DRY ADVECTION AND EXTENSIVE CIRRUS SHIELD
NOTED ACROSS THE SOUTHWEST HALF OF THE FORECAST AREA THIS AFTERNOON.
IF CLOUD COVER IS QUICK TO DIMINISH TONIGHT...W/ LACK OF ANY
CONVECTIVE DEBRIS...THEN DENSE FOG CHANCES WOULD INCREASE TOWARD
TOMORROW MORNING...ESPECIALLY SE. WILL MONITOR TRENDS THROUGH THE
EVENING AND WILL UPDATE AS NECESSARY.
RIDGING BUILDS EAST OF THE AREA THROUGH THE DAY ON WEDNESDAY...WITH
MOSTLY SUNNY SKIES AND FAIR CONDITIONS. KEPT HIGH TEMPS SLIGHTLY
BELOW MAV...ALTHOUGH UPWARD ADJUSTMENT MAY BE NEEDED IN THE NEXT
FCST WITH WAA INTO THE AREA BY THE AFTERNOON HOURS ON THE WESTERN
PERIPHERY OF THE RIDGE.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 344 PM EDT TUE SEP 2 2014
THE GFS AND ECMWF HAVE APPEARED TO INITIALIZE THE UPSTREAM SHORT
WAVE WELL AND ALSO SEEM HAVE A REASONABLE TRACK WITH THIS SYSTEM
ACROSS THE CONUS THIS WEEK. THE ECMWF AND GFS HAVE ALSO SHOWN GOOD
CONSISTENCY FROM RUN TO RUN WITH THIS SYSTEM THE PAST SEVERAL RUNS.
LOW LEVEL THETA E AND MOISTURE FLUX WILL INCREASE RAPIDLY WEDNESDAY
NIGHT...ESPECIALLY NORTH AND NORTHWEST OF THE AREA. HAVE ADDED A
SMALL CHANCE FOR THUNDERSTORMS OVERNIGHT WEDNESDAY NIGHT ON THE
LEADING EDGE OF THIS THETA E ADVECTION OVER FAR NORTHWEST AREAS...
ESPECIALLY BERRIEN AND LAPORTE COUNTY. KEPT THURSDAY DRY AS THE
PRIMARY LOW LEVEL FORCING SHIFTS NORTH OF THE AREA AND AS A LOW
LEVEL INVERSION INCREASES AT THE BASE OF A WEAK TO MODERATE ELEVATED
MIXED LAYER. THE GFS MAV/MEX TEMPERATURES HAVE BEEN CONSISTENT AT
GENERALLY 5 TO 10 DEGREES ABOVE NORMAL FOR THURSDAY AND FRIDAY AND
APPEAR ON TRACK WITH 850 MB TEMPERATURES APPROACHING 20C.
THUNDERSTORM CHANCES LOOK BEST OVERNIGHT THURSDAY NIGHT THROUGH
FRIDAY NIGHT AS A COLD FRONT APPROACHES. GIVEN THE TIMING OF THE
FRONT AND SUBSTANTIAL INSTABILITY BY LATE THURSDAY AND FRIDAY
AFTERNOON/EARLY EVENING WITH CAPES AS HIGH AS 2000 TO 3000
J/KG...CONCERN FOR AN UPSTREAM CONVECTIVE COMPLEX TO DROP SOUTHEAST
OR SOUTH INTO THE FORECAST AREA AS RICH THETA E SPREADS OVER THE
AREA. EXPANDED THUNDERSTORM CHANCES THURSDAY NIGHT IN THIS REGARD.
OTHERWISE...KEPT STORM CHANCES FRIDAY AND FRIDAY NIGHT. OTHERWISE...
COOLER AND DRIER CONDITIONS CAN BE EXPECTED FOR THE WEEKEND INTO
NEXT WEEK WITH HIGHS IN THE 70S THROUGH TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 128 PM EDT TUE SEP 2 2014
DIFFUSE FRONTAL BOUNDARY PUSHING SOUTH THROUGH THE AREA AND UPPER
LEVEL SUPPORT SHIFTING NORTHEAST OF THE REGION THIS AFTERNOON
SHOULD YIELD IMPROVING CONDITIONS AT TERMINALS THROUGH THE FIRST
HALF OF THE TAF PD. LINGERING LOW LEVEL STRATUS SLOW TO MIX OUT
THROUGH MIDDAY...ESPECIALLY INVOF KFWA. BUT RECENT SATELLITE
TRENDS SUGGEST RAPID MIXING AND LIFTING/CLEARING OF ANY MVFR CIGS
THIS AFTERNOON. RIDGING BUILDS IN OVERNIGHT WITH CALMING WINDS AND
CLEARING SKIES. LEFT PREVIOUS FCST IN TACT WITH POTENTIAL FOR
MVFR/IFR FOG TOWARD DAYBREAK WEDNESDAY MORNING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MCD
SHORT TERM...NG
LONG TERM...SKIPPER
AVIATION...NG
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
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AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
401 PM CDT TUE SEP 2 2014
...UPDATED FOR LONG TERM...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 344 PM CDT TUE SEP 2 2014
THE MID TO UPPER LEVEL FLOW HAS BECOME ZONAL IN THE WAKE OF THE
MINOR SHORTWAVE TROUGH THAT TRAVERSED THE CENTRAL PLAINS MONDAY
EVENING. THE EFFECTIVE FRONTAL BOUNDARY AFTER ALL OF THE NIGHTTIME
CONVECTION WAS SITUATED ACROSS CENTRAL OKLAHOMA AND SOUTHERN
ARKANSAS. SOUTH OF THIS FRONT, TEMPERATURES WERE ABOVE 90 AS OF 2
PM, BUT ON THE COOL SIDE OF THE FRONT, MOST READINGS WERE IN THE
70S TO LOWER 80S. LEE TROUGHING WILL DEVELOP TONIGHT AND
WEDNESDAY IN RESPONSE TO THE ZONAL FLOW. LATE TONIGHT, WARMER MID
LEVEL TEMPERATURES WILL SPREAD ACROSS SOUTHWEST KANSAS, CAPPING
THE ELEVATED MOIST LAYER. THE NAM INDICATES THAT LOW LEVEL WINDS
WILL BECOME SOUTHERLY AS THE WARM FRONT SHIFTS INTO NORTHERN
KANSAS BY WEDNESDAY MORNING. HOWEVER, THE RAP SHOWS THE BOUNDARY
STILL SITUATED ALONG THE KANSAS/OKLAHOMA BORDER AT 12Z. SINCE WE
MAY MAINTAIN UPSLOPE SOUTHEASTERLY FLOW MOST OF THE NIGHT, I OPTED
TO BRING THE LOW CLOUDS AND FOG BACK IN TOWARD 09Z. A MID LEVEL
CLOUD DECK MAY DEVELOP AS THE LOW LEVEL JET DEVELOPS THIS EVENING
AND AN ELEVATED THUNDERSTORM OR TWO CAN`T BE COMPLETELY RULED OUT
OVER SOUTH CENTRAL KANSAS BEFORE THE STRONG CAPPING INVERSION
DEVELOPS.
ON WEDNESDAY, THE LEE TROUGH WILL BECOME ESTABLISHED ACROSS THE
HIGH PLAINS, WITH A WEAK SURFACE DRYLINE SITUATED ACROSS FAR
WESTERN KANSAS. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT
LATE IN THE DAY. HIGH TEMPERATURES WILL BE IN THE MID TO HIGH 90S,WITH
SOME READINGS CLOSE TO 100F.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 357 PM CDT TUE SEP 2 2014
A STRONG UPPER LEVEL SHORTWAVE TROUGH OVER THE PACIFIC NORTHWEST
WILL MOVE EASTWARD INTO THE NORTHERN PLAINS AND UPPER MIDWEST BY
FRIDAY. THIS SYSTEM WILL PUSH A COLD FRONT ACROSS WESTERN KANSAS AND
THE CENTRAL PLAINS ON THURSDAY BRINGING THE BEST CHANCES FOR SHOWERS
AND THUNDERSTORMS. THE STRONGEST MID AND UPPER LEVEL WINDS WILL BE
IN NEBRASKA, SO NOT EXPECTING LOTS OF SEVERE WITH THE FRONT. CAPE
VALUES AROUND 2000 J/KG WILL BE SUFFICIENT TO PRODUCE SOME SMALL
HAIL AND STRONG WINDS AS THE COLD FRONT SWEEPS ACROSS WESTERN KANSAS
TO NEAR DODGE CITY BY 7 PM THURSDAY AND THROUGH MEDICINE LODGE BY
AROUND MIDNIGHT.
HIGH TEMPERATURES WILL BE VERY WARM AHEAD OF THE COLD FRONT ON
THURSDAY WITH LOW TO MID AND UPPER 90S FORECAST. HIGHS THEN COOL
INTO THE 70S INTO FRIDAY WITH A CONTINUED CHANCE FOR MAINLY
AFTERNOON THUNDERSTORMS BEHIND THE FRONT IN MOIST SURFACE UPSLOPE
FLOW.
BY MONDAY HIGHS WARM BACK INTO THE 80S AS THE COOL HIGH PRESSURE
AREA MOVES EAST AND WARM SOUTHERLY WINDS INCREASE. MORE THUNDERSTORM
CHANCES CONTINUE INTO TUESDAY WITH DISTURBANCES IN SOUTHWEST FLOW
ALOFT AND UPPER JET.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM CDT TUE SEP 2 2014
ZONAL FLOW IN THE WAKE OF AN UPPER LEVEL DISTURBANCE WILL LEAD TO
RENEWED LEE TROUGHING AND A RETURN TO SOUTHERLY WINDS. AS A
RESULT, THE WARM FRONT OVER OKLAHOMA WILL ADVANCE NORTHWARD INTO
NORTHERN KANSAS TONIGHT. CIGS WILL GRADUALLY IMPROVE AT GCK/DDC TO
VFR THIS AFTERNOON WITH DAYTIME HEATING. GIVEN THE LACK OF UPSLOPE
COMPONENT TO THE WIND LATER TONIGHT, A RETURN TO LOW CIGS AND FOG
IS NOT EXPECTED.
THE RAP NOW INDICATES THAT LOW LEVEL SOUTHEAST FLOW WILL PERSIST
THROUGH 12Z, AND THUS LIFR/IFR CIGS AND VISBYS MAY DEVELOP BY 09Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 70 97 72 95 / 10 0 10 30
GCK 68 99 70 92 / 0 0 10 40
EHA 66 99 68 94 / 0 10 10 30
LBL 70 98 71 96 / 0 0 10 20
HYS 68 98 72 92 / 10 10 10 50
P28 72 97 74 97 / 30 10 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...KRUSE
AVIATION...FINCH
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
351 PM CDT TUE SEP 2 2014
...UPDATED FOR SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 344 PM CDT TUE SEP 2 2014
THE MID TO UPPER LEVEL FLOW HAS BECOME ZONAL IN THE WAKE OF THE
MINOR SHORTWAVE TROUGH THAT TRAVERSED THE CENTRAL PLAINS MONDAY
EVENING. THE EFFECTIVE FRONTAL BOUNDARY AFTER ALL OF THE NIGHTTIME
CONVECTION WAS SITUATED ACROSS CENTRAL OKLAHOMA AND SOUTHERN
ARKANSAS. SOUTH OF THIS FRONT, TEMPERATURES WERE ABOVE 90 AS OF 2
PM, BUT ON THE COOL SIDE OF THE FRONT, MOST READINGS WERE IN THE
70S TO LOWER 80S. LEE TROUGHING WLLL DEVELOP TONIGHT AND WEDNESDAY
IN RESPONSE TO THE ZONAL FLOW. LATE TONIGHT, WARMER MID LEVEL
TEMPERATURES WILL SPREAD ACROSS SOUTHWEST KANSAS, CAPPING THE
ELEVATED MOIST LAYER. THE NAM INDICATES THAT LOW LEVEL WINDS WILL
BECOME SOUTHERLY AS THE WARM FRONT SHIFTS INTO NORTHERN KANSAS BY
WEDNESDAY MORNING. HOWEVER, THE RAP SHOWS THE BOUNDARY STILL
SITUATED ALONG THE KANSAS/OKLAHOMA BORDER AT 12Z. SINCE WE MAY
MAINTAIN UPSLOPE SOUTHEASTERLY FLOW MOST OF THE NIGHT, I OPTED TO
BRING THE LOW CLOUDS AND FOG BACK IN TOWARD 09Z. A MID LEVEL
CLOUD DECK MAY DEVELOP AS THE LOW LEVEL JET DEVELOPS THIS EVENING
AND AN ELEVATED THUNDERSTORM OR TWO CAN`T BE COMPLETELY RULED OUT
OVER SOUTH CENTRAL KANSAS BEFORE THE STRONG CAPPING INVERSION
DEVELOPS.
ON WEDNESDAY, THE LEE TROUGH WILL BECOME ESTABLISHED ACROSS THE
HIGH PLAINS, WITH A WEAK SURFACE DRYLINE SITUATED ACROSS FAR
WESTERN KANSAS. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT
LATE IN THE DAY. HIGH TEMPERATURES WILL BE IN THE MID TO HIGH 90S,WITH
SOME READINGS CLOSE TO 100F.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM CDT TUE SEP 2 2014
THE LONGWAVE SYNOPTIC FLOW PATTERN WILL BE SOMEWHAT PROGRESSIVE
THROUGH THIS FORECAST, AT LEAST ENOUGH TO BRING SIGNIFICANT SENSIBLE
WEATHER CHANGES TO THE AREA FOR LATE IN THE WEEK. WEDNESDAY AND
THURSDAY WILL SEE SUNNY AND VERY WARM TO HOT TEMPERATURES, AS THE
UPPER JET LIFTS NORTHWARD ACROSS THE NORTHERN TIER OF STATES
ALLOWING THE LARGE SOUTHERN ROCKIES/SOUTHERN PLAINS HIGH PROVIDE
STRONG SUBSIDENCE, FULL INSOLATION AND SOUTHERLY SURFACE WINDS.
THE ECMWF/GFS AND NAM ARE IN EXCELLENT AGREEMENT IN BREAKING DOWN
THIS PATTERN BY THURSDAY AND BRINGING A COLD FRONT THROUGH THE
NORTHERN PLAINS OF WESTERN NEBRASKA AND AS FAR SOUTH AS WEST
CENTRAL KANSAS WITH THE LEADING COOLER AIR SURGE BY THURSDAY
AFTERNOON. CONVECTION COULD OCCUR LATE THURSDAY AFTERNOON OR
EVENING AS WELL WITH THIS COLD FRONT FEATURE, BUT UPPER
SUPPORT/DYNAMICS FOR WIDESPREAD STORM DEVELOPMENT IS LACKING. THE
UPPER JET WILL SINK SOUTHWARD THROUGH THE CENTRAL PLAINS AND
CENTRAL MISSISSIPPI VALLEY, DRIVING THE COLD FRONT FARTHER SOUTH
INTO THE SOUTHERN PLAINS BY SATURDAY MORNING. THE RESULT WILL BE
ADDITONAL CHANCES FOR POSSIBLY EVEN SEVERE STORMS, BUT PERHAPS
JUST POST SURFACE FRONTAL HIGH BASED CONVECTION FROM MID LEVEL
FRONTOGENESIS FRIDAY OR FRIDAY NIGHT WITH MUCH MORE PLEASANT
TEMPERATURES IN THE 70S.
A SLOW WARMING TREND IS LIKELY THROUGH THE LATE PART OF THE WEEKEND
INTO EARLY NEXT WEEK AS RETURN SOUTHERLY FLOW BECOMES REESTABLISHED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM CDT TUE SEP 2 2014
ZONAL FLOW IN THE WAKE OF AN UPPER LEVEL DISTURBANCE WILL LEAD TO
RENEWED LEE TROUGHING AND A RETURN TO SOUTHERLY WINDS. AS A
RESULT, THE WARM FRONT OVER OKLAHOMA WILL ADVANCE NORTHWARD INTO
NORTHERN KANSAS TONIGHT. CIGS WILL GRADUALLY IMPROVE AT GCK/DDC TO
VFR THIS AFTERNOON WITH DAYTIME HEATING.
THE RAP NOW INDICATES THAT LOW LEVEL SOUTHEAST FLOW WILL PERSIST
THROUGH 12Z, AND THUS LIFR/IFR CIGS AND VISBYS MAY DEVELOP BY 09Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 70 97 72 95 / 10 0 10 30
GCK 68 99 70 92 / 0 0 10 40
EHA 66 99 68 94 / 0 10 10 30
LBL 70 98 71 96 / 0 0 10 20
HYS 68 98 72 92 / 10 10 10 50
P28 72 97 74 97 / 30 10 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...RUSSELL
AVIATION...FINCH
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1247 PM CDT TUE SEP 2 2014
...UPDATED FOR AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 357 AM CDT TUE SEP 2 2014
AS OF 0845 UTC, STRONG THUNDERSTORMS WERE UNDERWAY ACROSS
COMANCHE, BARBER, AND CLARK COUNTY, TIED MOST CLOSELY TO A ZONE
OF FRONTOGENESIS AT AROUND 750MB STRETCHING FROM THE OKLAHOMA
PANHANDLE EAST- NORTHEASTWARD TO FAR SOUTH-CENTRAL KANSAS. THE
HIRES CONVECTIVE- ALLOWING MODELS PICKED UP ON THIS QUITE WELL IN
THE COMPOSITE REFLECTIVITY AND QPF FIELDS. THESE MODELS SHOW THE
CONVECTION MOVING OFF INTO NORTHERN OKLAHOMA BEFORE 1200 UTC, SO
WE WILL TAPER THE POPS DOWN AROUND THIS TIME. EARLIER IN THE
SHIFT, WE ADDED SOME AREAS OF 1/2SM FOG GENERALLY ALONG/SOUTH OF
THE ARKANSAS RIVER IN A ZONE OF SATURATED SURFACE AIR NORTH OF THE
WEAK SURFACE LOW. ANY FOG WHICH DEVELOPS SHOULD ERODE NOT TOO LONG
AFTER SUNRISE, HOWEVER LOW STRATUS IS EXPECTED TO HOLD ON THROUGH
LATE MORNING NORTH OF THE 850MB LOW. THIS MAY THROW A BIT OF A
CURVE BALL IN THE TEMPERATURES TODAY, SO WE ADJUSTED THEM DOWN
(USING A MODIFIED HRRR SOLUTION) OUT ACROSS THE WESTERN HALF FOR
THE FIRST HALF OF THE DAY WITH CLOUDS KEEPING A LID IN THE WARM-
UP. ONCE THE CLOUDS ERODE COMPLETELY BY MIDDAY/EARLY AFTERNOON,
TEMPERATURES WILL WARM INTO THE MID 80S. ANY SURFACE-BASED
CONVECTION LATE THIS AFTERNOON WILL BE DOWN ALONG THE SURFACE
FRONT ACROSS NORTHWEST OKLAHOMA. BY EARLY EVENING, SOME OF THE
THUNDERSTORM ACTIVITY MAY HEAD UP INTO BARBER COUNTY AND EXPAND IN
COVERAGE SOME AS LOW LEVEL JET STRENGTHENS AFTER SUNSET. RICH LOW
LEVEL MOISTURE LEADING TO 2000-3000 J/KG MOST-UNSTABLE CAPE WILL
SUPPORT RENEWED SEVERE WEATHER RISK, EVEN WITH ELEVATED STORMS
DURING THE LATE NIGHT HOURS TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 326 AM CDT TUE SEP 2 2014
THE LONGWAVE SYNOPTIC FLOW PATTERN WILL BE SOMEWHAT PROGRESSIVE
THROUGH THIS FORECAST, AT LEAST ENOUGH TO BRING SIGNIFICANT SENSIBLE
WEATHER CHANGES TO THE AREA FOR LATE IN THE WEEK. WEDNESDAY AND
THURSDAY WILL SEE SUNNY AND VERY WARM TO HOT TEMPERATURES, AS THE
UPPER JET LIFTS NORTHWARD ACROSS THE NORTHERN TIER OF STATES
ALLOWING THE LARGE SOUTHERN ROCKIES/SOUTHERN PLAINS HIGH PROVIDE
STRONG SUBSIDENCE, FULL INSOLATION AND SOUTHERLY SURFACE WINDS.
THE ECMWF/GFS AND NAM ARE IN EXCELLENT AGREEMENT IN BREAKING DOWN
THIS PATTERN BY THURSDAY AND BRINGING A COLD FRONT THROUGH THE
NORTHERN PLAINS OF WESTERN NEBRASKA AND AS FAR SOUTH AS WEST
CENTRAL KANSAS WITH THE LEADING COOLER AIR SURGE BY THURSDAY
AFTERNOON. CONVECTION COULD OCCUR LATE THURSDAY AFTERNOON OR
EVENING AS WELL WITH THIS COLD FRONT FEATURE, BUT UPPER
SUPPORT/DYNAMICS FOR WIDESPREAD STORM DEVELOPMENT IS LACKING. THE
UPPER JET WILL SINK SOUTHWARD THROUGH THE CENTRAL PLAINS AND
CENTRAL MISSISSIPPI VALLEY, DRIVING THE COLD FRONT FARTHER SOUTH
INTO THE SOUTHERN PLAINS BY SATURDAY MORNING. THE RESULT WILL BE
ADDITONAL CHANCES FOR POSSIBLY EVEN SEVERE STORMS, BUT PERHAPS
JUST POST SURFACE FRONTAL HIGH BASED CONVECTION FROM MID LEVEL
FRONTOGENESIS FRIDAY OR FRIDAY NIGHT WITH MUCH MORE PLEASANT
TEMPERATURES IN THE 70S.
A SLOW WARMING TREND IS LIKELY THROUGH THE LATE PART OF THE WEEKEND
INTO EARLY NEXT WEEK AS RETURN SOUTHERLY FLOW BECOMES REESTABLISHED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM CDT TUE SEP 2 2014
ZONAL FLOW IN THE WAKE OF AN UPPER LEVEL DISTURBANCE WILL LEAD TO
RENEWED LEE TROUGHING AND A RETURN TO SOUTHERLY WINDS. AS A
RESULT, THE WARM FRONT OVER OKLAHOMA WILL ADVANCE NORTHWARD INTO
NORTHERN KANSAS TONIGHT. CIGS WILL GRADUALLY IMPROVE AT GCK/DDC TO
VFR THIS AFTERNOON WITH DAYTIME HEATING. GIVEN THE LACK OF UPSLOPE
COMPONENT TO THE WIND LATER TONIGHT, A RETURN TO LOW CIGS AND FOG
IS NOT EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 84 68 98 71 / 10 10 0 0
GCK 82 67 100 71 / 10 0 0 10
EHA 85 66 99 69 / 0 0 10 10
LBL 86 69 100 72 / 0 10 0 10
HYS 86 67 99 73 / 0 10 10 10
P28 89 72 98 74 / 40 30 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...RUSSELL
AVIATION...FINCH
AREA FORECAST DISCUSSION
NWS JACKSON KY
345 PM EDT TUE SEP 2 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 343 PM EDT TUE SEP 2 2014
A LINE OF THUNDERSTORMS WITH HEAVY RAINS HAS FORMED ALONG AN OLD
OUTFLOW BOUNDARY ACROSS THE MID SECTION OF EASTERN KENTUCKY. SOME OF
THE STORMS HAVE BECOME NEAR SEVERE AND EXPECT SOME SEVERE STORM
WARNINGS TO BE ISSUED DURING THE NEXT FEW HOURS. THE MAIN THREAT
WILL BE WIND GUSTS. ANOTHER CONCERN IS THAT WITH UNIDIRECTIONAL FLOW
AND HIGH PRECIPITABLE WATER...FLOODING CONCERNS WILL BE A REAL ISSUE
THIS AFTERNOON AND EVENING...MAINLY IN THE SOUTHERN HALF OF EASTERN
KENTUCKY AND ESPECIALLY ALONG THE OLD OUTFLOW BOUNDARY. EXPECT THE
FRONT TO PUSH THE PRECIPITATION SOUTH OF THE AREA BY WEDNESDAY
MORNING. IN GENERAL...THE HRRR AND RAP HAVE NOT BEEN DOING TOO WELL
WITH THIS SYSTEM SO FAR. WEDNESDAY FIGURES TO BE A LITTLE MORE
COMFORTABLE AS THE HUMIDITY WILL BE A LITTLE LOWER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 301 PM EDT TUE SEP 2 2014
THE MODELS BEGIN THE EXTENDED PERIOD IN PRETTY GOOD AGREEMENT ONCE
AGAIN...WITH A RIDGE OF HIGH PRESSURE...BOTH ALOFT AND AT THE
SURFACE...CENTERED OVER THE EASTERN GULF OF MEXICO...ALONG WITH A
WELL DEFINED TROUGH OF LOW PRESSURE ALOFT TAKING SHAPE OVER THE
NORTHERN PLAINS. THE MODELS HAVE THE RIDGE STEADILY BREAKING DOWN
TO BEGIN THE PERIOD...WITH SHOWERS AND STORMS POPPING UP BENEATH IT
ACROSS THE TENNESSEE VALLEY DOWN TO THE GULF AND ACROSS PORTIONS OF
THE SOUTHEASTERN CONUS. AS THE TROUGH EVOLVES AND STRENGTHENS...IT
WILL EJECT OUT OF THE PLAINS WEDNESDAY AND THURSDAY...AND PUSH
ACROSS THE GREAT LAKES AND OHIO VALLEY REGIONS. THE COLD FRONT
TRAILING FROM THIS UPPER LOW WILL END UP BEING OUR WEATHER MAKER FOR
THE UPCOMING WEEKEND. THE FRONT IS EXPECTED TO INTERACT WITH
MOISTURE COMING OFF THE GULF OF MEXICO ON SOUTHWESTERLY WINDS. THE
FRONT WILL HAVE A DIFFICULT TIME MOVING EASTWARD...HOWEVER...AS THE
RIDGE DIGS IN A BIT JUST OFF THE SOUTHEAST COAST AND FLOW ALOFT
BECOMES MORE ZONAL. THERE WILL BE A GOOD CHANCE OF RAIN FRIDAY
MORNING THROUGH SUNDAY MORNING...AS LIFT AND MOISTURE ALONG THE
SLUGGISH FRONT SET OFF REPEATED ROUNDS OF SHOWERS AND STORMS. THE
RAIN SHOULD FINALLY MOVE OUT OF THE AREA SUNDAY EVENING...AS THE
FRONT FINALLY MOVES OUT OF THE AREA.
TEMPERATURES TO BEGIN THE PERIOD LOOK TO BE ABOVE NORMAL...WITH
HIGHS TOPPING OUT AROUND IN THE MID TO UPPER 80S THURSDAY AND
FRIDAY. ONCE THE FRONT STALLS ACROSS THE AREA AND PRECIPITATION
BECOMES MORE WIDESPREAD...TEMPERATURES WILL LIKELY MAX OUT BELOW
NORMAL VALUES SATURDAY THROUGH MONDAY. THE POSITIONING OF THE FRONT
OVER THE WEEKEND WILL ALLOW FOR SOME COOLER AND DRIER AIR TO FILTER
INTO THE AREA. HIGHS ON SATURDAY SHOULD BE JUST BELOW NORMAL...AS
THE BULK OF COOL AIR SHOULD STILL BE TRAPPED NORTH OF THE OHIO
RIVER. ON SUNDAY...HOWEVER...ONCE WINDS HAVE SHIFTED TO THE
NORTH...TEMPERATURES WILL BE QUITE COOL...WITH READINGS PEAKING IN
THE MID TO UPPER 70S FOR MOST LOCATIONS. THE NORTHERLY FLOW WILL
ONLY ALLOW FOR A SMALL WARM UP ON MONDAY...AS HIGHS THAT DAY WILL
LIKELY ONLY TOP OUT IN THE UPPER 70S AND LOWER 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 156 PM EDT TUE SEP 2 2014
EASTERN KENTUCKY IS PRIMED FOR THUNDERSTORMS AS MOIST AND UNSTABLE
CONDITIONS ARE PREVALENT ACROSS THE AREA. THERE IS AN OLD OUTFLOW
BOUNDARY BISECTING THE AREA WHICH WE ARE WATCHING AS A FOCAL POINT
FOR CONVECTIVE INITIATION AND THERE IS ALSO A FRONT WHICH IS MOVING
TOWARD THE AREA FROM THE NORTHWEST WITH LOTS OF PREFRONTAL CONVECTION
OUT AHEAD OF IT. MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES
THIS AFTERNOON AND EVENING EXCEPT FOR IN THE VICINITY OF THE
THUNDERSTORMS AND RAIN SHOWERS. PUT SOME TEMPO CONDITIONS IN THE TAF
AS THE BEST ESTIMATE AS TO WHEN THUNDERSTORMS ARE MOST LIKELY AFFECT
THEM. EXPECT SOME VLIFR TO FORM AT THE TAF STATIONS AS WELL AS THE
VALLEYS LATER THIS EVENING AS THE CONVECTION MOVES OFF TO THE SOUTH
AND EAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJ
LONG TERM...AR
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
302 PM EDT TUE SEP 2 2014
.UPDATE...
ISSUED AT 948 AM EDT TUE SEP 2 2014
THE FORECAST FOR THIS AFTERNOON HAS BECOME COMPLICATED BY THE
REMNANTS OF AN MCS OVER THE OHIO VALLEY AND THE OUTFLOW BOUNDARY
WHICH IS CURRENTLY MOVING INTO THE BLUEGRASS. CURRENT THINKING IS
THAT THE OUTFLOW BOUNDARY WILL GENERALLY WEAKEN AS IT CONTINUES
MOVING TO THE SOUTHEAST. THIS SHOULD BE TEMPORARY AND WILL THEN BE
THE FOCUS OF DEVELOPMENT LATER IN THE AFTERNOON. SO PRETTY MUCH GOING
WITH TWO PRONGS. THE FIRST BEING REDEVELOPMENT WITH THE OUTFLOW
BOUNDARY AND THE SECOND BEING THE PREFRONTAL ACTIVITY. THE SEVERE
THREAT TODAY WILL BE EFFECTED BY HOW MUCH DEBRIS CLOUD IS ABLE TO
MOVE INTO THE AREA. THE LOW LEVEL INSTABILITY WILL BE EFFECTED BY
EFFECTED BY THE CLOUDS. THE LATEST NAM BUFFER HAS REALLY BACKED OFF
FROM YESTERDAY WITH HALF THE CAPE THAN WHAT WAS FORECAST YESTERDAY.
ALSO MISSING IS THE DRY AIR POCKETS ALOFT WHICH WOULD HAVE BEEN
HELPFUL FOR WET MICROBURSTS TO OCCUR. CAN NOT RULE OUT SEVERE
THUNDERSTORMS...HOWEVER THE CHANCES HAVE GONE DOWN. MOST LIKELY WILL
STILL SEE A COUPLE OF SEVERE STORMS WITH THIS SYSTEM. UPDATED THE
FORECAST TO REFLECT THE CURRENT CONDITIONS AND MODEL TRENDS.
UPDATE ISSUED AT 649 AM EDT TUE SEP 2 2014
NO SIGNIFICANT CHANGES MADE THIS MORNING. LINE OF SHOWERS AND STORMS
EXTENDS FROM CINCINNATI SOUTHWEST TO THE NORTHWEST SIDE OF
LOUISVILLE. THIS LINE CONTINUES TO SLOWLY WEAKEN AS IT MOVES EAST. IF
IT WERE TO HOLD TOGETHER...LOOKS LIKE IT MAY WORK INTO THE BLUEGRASS
COUNTIES AFTER 13Z. HOWEVER...GIVEN THE TREND THIS SEEMS UNLIKELY AND
AT BEST PERHAPS AN ISOLATED SHOWER CAN HOLD TOGETHER. MAIN CONCERN
CONTINUES TO BE LATER TODAY...PRIMARILY AFTER 2 PM AS OUTFLOW FROM
THIS MORNINGS CONVECTION REDEVELOPS SHOWERS AND STORMS. NOT SURE THE
COVERAGE WILL BE ALL THAT GREAT AFTER LOOKING AT THE LATEST HRRR AND
NEW 06Z MAV GUIDANCE. BOTH OF THESE MODELS HAVE BACKED OFF
SIGNIFICANTLY ON THE CHANCES OF RAIN TODAY. HOWEVER...GOING TO STAY
THE COURSE AS THE TROUGH IS STILL FAIRLY DEFINED AND OUTFLOW HAS
ALREADY DEFINED A BOUNDARY FOR NEW CONVECTION TO DEVELOP.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT TUE SEP 2 2014
PRESENTLY...A SHORTWAVE TROUGH IS PUSHING INTO THE OHIO RIVER VALLEY
REGION. AN MCS DEVELOPED YESTERDAY EVENING HEAD OF THIS TROUGH AND
IS NOW MARCHING EASTWARD INTO CENTRAL/SOUTHERN INDIANA...STRETCHING
BACK TO THE SOUTHWEST ACROSS SOUTHERN ILLINOIS. IR SATELLITE HAS
SHOWN SOME WARMING WITH THE CLOUD TOPS OVER THE PAST HOUR OR
TWO...INDICATING THAT THIS MCS MAY ALREADY BE ON THE DECLINE. IN
FACT...THE HRRR SUPPORTS THE IDEA OF A DYING MCS AS IT TRIES TO PUSH
INTO CENTRAL KENTUCKY TOWARDS DAYBREAK. CANNOT RULE OUT A FEW SHOWERS
PUSHING INTO THE BLUEGRASS SHORTLY AFTER 8 AM...BUT ANTICIPATE MORE
OF THE ACTION WITH THE SHORTWAVE TROUGH WILL COME LATER THIS
AFTERNOON AS WE GENERATE SOME INSTABILITY. WITH THIS IN MIND...PLAN
TO BACK OFF THE POPS THROUGH MIDDAY WITH JUST SOME ISOLATED SHOWERS
FOR AREAS NORTH OF I-64. OUTFLOW FROM THE DYING MCS WILL BE PUSHING
ACROSS EASTERN KENTUCKY EARLY THIS AFTERNOON...AND COULD KICK START
THE CONVECTION AS IT ENCOUNTERS SOME DECENT INSTABILITY. THE FORCING
ALOFT SHOULD ALLOW FOR FAIRLY GOOD SHOWER AND THUNDERSTORM COVERAGE
BY MID TO LATE AFTERNOON. WITH BULK SHEAR VALUES OF 30-40KTS THIS
AFTERNOON...A SEVERE THREAT WOULD EXIST AS THUNDERSTORMS COULD PUT
OUT SOME DAMAGING WIND GUSTS. THE SHEAR PROFILES WEAKEN BY MID
EVENING AND THE LOSS OF DAYTIME INSTABILITY SHOULD YIELD WEAKENING
STORMS AFTER 6 PM. HOWEVER...A FEW GUSTY WINDS MAY STILL BE POSSIBLE
THROUGH 8 OR 9 PM.
THE SHORTWAVE TROUGH WILL STALL A COLD FRONT ACROSS SOUTHERN
KENTUCKY BY LATE THIS EVENING. GIVEN THE PRESENCE OF THIS
BOUNDARY...AND PLENTY OF MOISTURE...IT MAY BE POSSIBLE TO SEE
ISOLATED SHOWERS THROUGH THE NIGHT ACROSS THE SOUTHERN HALF OF
KENTUCKY. THIS BOUNDARY WILL LINGER AROUND INTO WEDNESDAY AND WITH
INSTABILITY AGAIN RAMPING UP DURING THE AFTERNOON...WE COULD BE
LOOKING AT A FEW MORE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HOWEVER...BY WEDNESDAY...VERY LITTLE SHEAR IS
PRESENT...SO WE SHOULD SEE MORE ORDINARY THUNDERSTORMS WITH NO SEVERE
THREAT.
TEMPERATURES OVER THE NEXT 2 DAYS SHOULD BE FAIRLY SIMILAR TO WHAT WE
HAVE SEEN LATELY WITH HIGHS INTO THE LOW TO MID 80S. SAME CAN BE SAID
FOR LOWS TONIGHT WITH READINGS GENERALLY AROUND 70.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 301 PM EDT TUE SEP 2 2014
THE MODELS BEGIN THE EXTENDED PERIOD IN PRETTY GOOD AGREEMENT ONCE
AGAIN...WITH A RIDGE OF HIGH PRESSURE...BOTH ALOFT AND AT THE
SURFACE...CENTERED OVER THE EASTERN GULF OF MEXICO...ALONG WITH A
WELL DEFINED TROUGH OF LOW PRESSURE ALOFT TAKING SHAPE OVER THE
NORTHERN PLAINS. THE MODELS HAVE THE RIDGE STEADILY BREAKING DOWN
TO BEGIN THE PERIOD...WITH SHOWERS AND STORMS POPPING UP BENEATH IT
ACROSS THE TENNESSEE VALLEY DOWN TO THE GULF AND ACROSS PORTIONS OF
THE SOUTHEASTERN CONUS. AS THE TROUGH EVOLVES AND STRENGTHENS...IT
WILL EJECT OUT OF THE PLAINS WEDNESDAY AND THURSDAY...AND PUSH
ACROSS THE GREAT LAKES AND OHIO VALLEY REGIONS. THE COLD FRONT
TRAILING FROM THIS UPPER LOW WILL END UP BEING OUR WEATHER MAKER FOR
THE UPCOMING WEEKEND. THE FRONT IS EXPECTED TO INTERACT WITH
MOISTURE COMING OFF THE GULF OF MEXICO ON SOUTHWESTERLY WINDS. THE
FRONT WILL HAVE A DIFFICULT TIME MOVING EASTWARD...HOWEVER...AS THE
RIDGE DIGS IN A BIT JUST OFF THE SOUTHEAST COAST AND FLOW ALOFT
BECOMES MORE ZONAL. THERE WILL BE A GOOD CHANCE OF RAIN FRIDAY
MORNING THROUGH SUNDAY MORNING...AS LIFT AND MOISTURE ALONG THE
SLUGGISH FRONT SET OFF REPEATED ROUNDS OF SHOWERS AND STORMS. THE
RAIN SHOULD FINALLY MOVE OUT OF THE AREA SUNDAY EVENING...AS THE
FRONT FINALLY MOVES OUT OF THE AREA.
TEMPERATURES TO BEGIN THE PERIOD LOOK TO BE ABOVE NORMAL...WITH
HIGHS TOPPING OUT AROUND IN THE MID TO UPPER 80S THURSDAY AND
FRIDAY. ONCE THE FRONT STALLS ACROSS THE AREA AND PRECIPITATION
BECOMES MORE WIDESPREAD...TEMPERATURES WILL LIKELY MAX OUT BELOW
NORMAL VALUES SATURDAY THROUGH MONDAY. THE POSITIONING OF THE FRONT
OVER THE WEEKEND WILL ALLOW FOR SOME COOLER AND DRIER AIR TO FILTER
INTO THE AREA. HIGHS ON SATURDAY SHOULD BE JUST BELOW NORMAL...AS
THE BULK OF COOL AIR SHOULD STILL BE TRAPPED NORTH OF THE OHIO
RIVER. ON SUNDAY...HOWEVER...ONCE WINDS HAVE SHIFTED TO THE
NORTH...TEMPERATURES WILL BE QUITE COOL...WITH READINGS PEAKING IN
THE MID TO UPPER 70S FOR MOST LOCATIONS. THE NORTHERLY FLOW WILL
ONLY ALLOW FOR A SMALL WARM UP ON MONDAY...AS HIGHS THAT DAY WILL
LIKELY ONLY TOP OUT IN THE UPPER 70S AND LOWER 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 156 PM EDT TUE SEP 2 2014
EASTERN KENTUCKY IS PRIMED FOR THUNDERSTORMS AS MOIST AND UNSTABLE
CONDITIONS ARE PREVALENT ACROSS THE AREA. THERE IS AN OLD OUTFLOW
BOUNDARY BISECTING THE AREA WHICH WE ARE WATCHING AS A FOCAL POINT
FOR CONVECTIVE INITIATION AND THERE IS ALSO A FRONT WHICH IS MOVING
TOWARD THE AREA FROM THE NORTHWEST WITH LOTS OF PREFRONTAL CONVECTION
OUT AHEAD OF IT. MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES
THIS AFTERNOON AND EVENING EXCEPT FOR IN THE VICINITY OF THE
THUNDERSTORMS AND RAIN SHOWERS. PUT SOME TEMPO CONDITIONS IN THE TAF
AS THE BEST ESTIMATE AS TO WHEN THUNDERSTORMS ARE MOST LIKELY AFFECT
THEM. EXPECT SOME VLIFR TO FORM AT THE TAF STATIONS AS WELL AS THE
VALLEYS LATER THIS EVENING AS THE CONVECTION MOVES OFF TO THE SOUTH
AND EAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...KAS
LONG TERM...AR
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
156 PM EDT TUE SEP 2 2014
.UPDATE...
ISSUED AT 948 AM EDT TUE SEP 2 2014
THE FORECAST FOR THIS AFTERNOON HAS BECOME COMPLICATED BY THE
REMNANTS OF AN MCS OVER THE OHIO VALLEY AND THE OUTFLOW BOUNDARY
WHICH IS CURRENTLY MOVING INTO THE BLUEGRASS. CURRENT THINKING IS
THAT THE OUTFLOW BOUNDARY WILL GENERALLY WEAKEN AS IT CONTINUES
MOVING TO THE SOUTHEAST. THIS SHOULD BE TEMPORARY AND WILL THEN BE
THE FOCUS OF DEVELOPMENT LATER IN THE AFTERNOON. SO PRETTY MUCH GOING
WITH TWO PRONGS. THE FIRST BEING REDEVELOPMENT WITH THE OUTFLOW
BOUNDARY AND THE SECOND BEING THE PREFRONTAL ACTIVITY. THE SEVERE
THREAT TODAY WILL BE EFFECTED BY HOW MUCH DEBRIS CLOUD IS ABLE TO
MOVE INTO THE AREA. THE LOW LEVEL INSTABILITY WILL BE EFFECTED BY
EFFECTED BY THE CLOUDS. THE LATEST NAM BUFFER HAS REALLY BACKED OFF
FROM YESTERDAY WITH HALF THE CAPE THAN WHAT WAS FORECAST YESTERDAY.
ALSO MISSING IS THE DRY AIR POCKETS ALOFT WHICH WOULD HAVE BEEN
HELPFUL FOR WET MICROBURSTS TO OCCUR. CAN NOT RULE OUT SEVERE
THUNDERSTORMS...HOWEVER THE CHANCES HAVE GONE DOWN. MOST LIKELY WILL
STILL SEE A COUPLE OF SEVERE STORMS WITH THIS SYSTEM. UPDATED THE
FORECAST TO REFLECT THE CURRENT CONDITIONS AND MODEL TRENDS.
UPDATE ISSUED AT 649 AM EDT TUE SEP 2 2014
NO SIGNIFICANT CHANGES MADE THIS MORNING. LINE OF SHOWERS AND STORMS
EXTENDS FROM CINCINNATI SOUTHWEST TO THE NORTHWEST SIDE OF
LOUISVILLE. THIS LINE CONTINUES TO SLOWLY WEAKEN AS IT MOVES EAST. IF
IT WERE TO HOLD TOGETHER...LOOKS LIKE IT MAY WORK INTO THE BLUEGRASS
COUNTIES AFTER 13Z. HOWEVER...GIVEN THE TREND THIS SEEMS UNLIKELY AND
AT BEST PERHAPS AN ISOLATED SHOWER CAN HOLD TOGETHER. MAIN CONCERN
CONTINUES TO BE LATER TODAY...PRIMARILY AFTER 2 PM AS OUTFLOW FROM
THIS MORNINGS CONVECTION REDEVELOPS SHOWERS AND STORMS. NOT SURE THE
COVERAGE WILL BE ALL THAT GREAT AFTER LOOKING AT THE LATEST HRRR AND
NEW 06Z MAV GUIDANCE. BOTH OF THESE MODELS HAVE BACKED OFF
SIGNIFICANTLY ON THE CHANCES OF RAIN TODAY. HOWEVER...GOING TO STAY
THE COURSE AS THE TROUGH IS STILL FAIRLY DEFINED AND OUTFLOW HAS
ALREADY DEFINED A BOUNDARY FOR NEW CONVECTION TO DEVELOP.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT TUE SEP 2 2014
PRESENTLY...A SHORTWAVE TROUGH IS PUSHING INTO THE OHIO RIVER VALLEY
REGION. AN MCS DEVELOPED YESTERDAY EVENING HEAD OF THIS TROUGH AND
IS NOW MARCHING EASTWARD INTO CENTRAL/SOUTHERN INDIANA...STRETCHING
BACK TO THE SOUTHWEST ACROSS SOUTHERN ILLINOIS. IR SATELLITE HAS
SHOWN SOME WARMING WITH THE CLOUD TOPS OVER THE PAST HOUR OR
TWO...INDICATING THAT THIS MCS MAY ALREADY BE ON THE DECLINE. IN
FACT...THE HRRR SUPPORTS THE IDEA OF A DYING MCS AS IT TRIES TO PUSH
INTO CENTRAL KENTUCKY TOWARDS DAYBREAK. CANNOT RULE OUT A FEW SHOWERS
PUSHING INTO THE BLUEGRASS SHORTLY AFTER 8 AM...BUT ANTICIPATE MORE
OF THE ACTION WITH THE SHORTWAVE TROUGH WILL COME LATER THIS
AFTERNOON AS WE GENERATE SOME INSTABILITY. WITH THIS IN MIND...PLAN
TO BACK OFF THE POPS THROUGH MIDDAY WITH JUST SOME ISOLATED SHOWERS
FOR AREAS NORTH OF I-64. OUTFLOW FROM THE DYING MCS WILL BE PUSHING
ACROSS EASTERN KENTUCKY EARLY THIS AFTERNOON...AND COULD KICK START
THE CONVECTION AS IT ENCOUNTERS SOME DECENT INSTABILITY. THE FORCING
ALOFT SHOULD ALLOW FOR FAIRLY GOOD SHOWER AND THUNDERSTORM COVERAGE
BY MID TO LATE AFTERNOON. WITH BULK SHEAR VALUES OF 30-40KTS THIS
AFTERNOON...A SEVERE THREAT WOULD EXIST AS THUNDERSTORMS COULD PUT
OUT SOME DAMAGING WIND GUSTS. THE SHEAR PROFILES WEAKEN BY MID
EVENING AND THE LOSS OF DAYTIME INSTABILITY SHOULD YIELD WEAKENING
STORMS AFTER 6 PM. HOWEVER...A FEW GUSTY WINDS MAY STILL BE POSSIBLE
THROUGH 8 OR 9 PM.
THE SHORTWAVE TROUGH WILL STALL A COLD FRONT ACROSS SOUTHERN
KENTUCKY BY LATE THIS EVENING. GIVEN THE PRESENCE OF THIS
BOUNDARY...AND PLENTY OF MOISTURE...IT MAY BE POSSIBLE TO SEE
ISOLATED SHOWERS THROUGH THE NIGHT ACROSS THE SOUTHERN HALF OF
KENTUCKY. THIS BOUNDARY WILL LINGER AROUND INTO WEDNESDAY AND WITH
INSTABILITY AGAIN RAMPING UP DURING THE AFTERNOON...WE COULD BE
LOOKING AT A FEW MORE ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS. HOWEVER...BY WEDNESDAY...VERY LITTLE SHEAR IS
PRESENT...SO WE SHOULD SEE MORE ORDINARY THUNDERSTORMS WITH NO SEVERE
THREAT.
TEMPERATURES OVER THE NEXT 2 DAYS SHOULD BE FAIRLY SIMILAR TO WHAT WE
HAVE SEEN LATELY WITH HIGHS INTO THE LOW TO MID 80S. SAME CAN BE SAID
FOR LOWS TONIGHT WITH READINGS GENERALLY AROUND 70.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 418 AM EDT TUE SEP 2 2014
THE FRONTAL BOUNDARY REFERENCED IN THE SHORT TERM WILL BE DISSOLVING
EARLY IN THE LONG TERM PERIOD...BUT THERE SHOULD STILL BE DRY AIR IN
PLACE WEDNESDAY NIGHT...ESPECIALLY ALOFT. IF ANY CONVECTIVE PRECIP
CAN DEVELOP OFF OF LOW LEVEL MOISTURE ON WEDNESDAY AFTERNOON...IT
SHOULD DIE OUT BY NIGHT AS HEATING IS LOST AND SUPPORT ALOFT WILL
LIKELY BE LACKING.
DEEPER MOISTURE WILL MAKE A COMEBACK LATE IN THE WEEK AND MAY FUEL
A RESURGENCE OF SHOWERS AND THUNDERSTORMS...BUT A SUBTROPICAL RIDGE
ALOFT OVER THE SE CONUS WILL HELP TO KEEP COVERAGE LIMITED FOR A
WHILE. THE RIDGE WILL WEAKEN AND GET SUPPRESSED BY A BROAD TROUGH
DROPPING SE INTO THE NE CONUS DURING THE WEEKEND. THIS WILL ALLOW A
COLD FRONT TO MOVE INTO OUR REGION FROM THE NW. THE SCENARIO WILL
ALLOW AN INCREASE IN PRECIP COVERAGE...WITH A PEAK EXPECTED ON
SATURDAY. EVEN THOUGH THE FRONT SHOULD PASS BY SUNDAY...THE MODELS
STILL LEAVE SOME QUESTION AS TO HOW EFFECTIVE THE FRONT WILL BE AT
BRINGING IN A DRIER AIR MASS. HAVE HELD ONTO LOW POPS IN THE
AFTERNOON AND EVENING ON SUNDAY AND MONDAY...ESPECIALLY IN OUR SE
COUNTIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 156 PM EDT TUE SEP 2 2014
EASTERN KENTUCKY IS PRIMED FOR THUNDERSTORMS AS MOIST AND UNSTABLE
CONDITIONS ARE PREVALENT ACROSS THE AREA. THERE IS AN OLD OUTFLOW
BOUNDARY BISECTING THE AREA WHICH WE ARE WATCHING AS A FOCAL POINT
FOR CONVECTIVE INITIATION AND THERE IS ALSO A FRONT WHICH IS MOVING
TOWARD THE AREA FROM THE NORTHWEST WITH LOTS OF PREFRONTAL CONVECTION
OUT AHEAD OF IT. MAINLY VFR CONDITIONS ARE EXPECTED AT THE TAF SITES
THIS AFTERNOON AND EVENING EXCEPT FOR IN THE VICINITY OF THE
THUNDERSTORMS AND RAIN SHOWERS. PUT SOME TEMPO CONDITIONS IN THE TAF
AS THE BEST ESTIMATE AS TO WHEN THUNDERSTORMS ARE MOST LIKELY AFFECT
THEM. EXPECT SOME VLIFR TO FORM AT THE TAF STATIONS AS WELL AS THE
VALLEYS LATER THIS EVENING AS THE CONVECTION MOVES OFF TO THE SOUTH
AND EAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...KAS
LONG TERM...HAL
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
359 PM EDT TUE SEP 2 2014
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL PUSH ACROSS THE NORTH COUNTRY
THROUGH THE EVENING HOURS AHEAD OF A COLD FRONT. EXPECT LOCALLY
HEAVY DOWNPOURS AND GUSTY WINDS WITH THE STRONGER STORMS. SUNNY,
DRY AND COOLER WEATHER WILL LAST INTO THURSDAY. WARM SUMMER WEATHER
RETURNS FRIDAY BUT WILL BE SHORT LIVED AS ANOTHER COLD FRONT SWEEPS IN
EARLY SATURDAY GIVING A TASTE OF FALL-LIKE WEATHER FOR SUNDAY AND
EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 8 AM WEDNESDAY MORNING/...
AS OF 355 PM EDT TUESDAY...WELL, THE ATMOSPHERE IS FAIRLY PRIMED.
VERY WARM AND HUMID AIRMASS IS RESULTING IN MODEST SURFACE BASED
INSTABILITY (CAPE PUSHING 2000 J/KG AND LIFTED INDEX OF -2 TO
-4C). SO FAR THE ACTIVITY HAS BEEN SPARSE ACROSS THE FORECAST
AREA, HOWEVER RADAR SHOWS THE BUILDING LINE OF SHOWERS AND
THUNDERSTORMS OUT ACROSS ONTARIO. THESE STORMS SHOULD BE CROSSING
INTO THE UNITED STATES IN THE NEXT COUPLE OF HOURS. STILL LIKE HOW
THE HRRR AND OUR LOCAL 6KM WRF ARE HANDLING THE EVOLUTION OF THE
CONVECTION. STILL LOOKS LIKE AN ETA INTO THE CHAMPLAIN VALLEY
DURING THE EVENING (LET`S GO WITH 6-8PM) AND THEN INTO EASTERN
VERMONT BY 10PM. UPPER LEVEL SHORTWAVE WHICH IS THE PRIMARY
TRIGGER FOR THE CONVECTION IS NOW OVER MICHIGAN AND STARTING TO
LIFT NORTHEAST. OUT AHEAD OF THAT SHORT WAVE THE WIND FIELDS AND
RELATED SHEAR INCREASE, BUT AT THE SAME TIME WE ARE GETTING CLOSER
TO SUNSET AND LOSS OF HEATING. SO IT`S A BATTLE BETWEEN TIMING OF
THE BEST DYNAMICS VS BEST INSTABILITY.
AT THIS POINT STILL SEE NOTHING TO CHANGE THE IDEA THAT WE`LL HAVE
AT LEAST A FEW STRONG T-STORMS AROUND, ESPECIALLY THIS EVENING AND
MAINLY WEST OF THE GREEN MOUNTAINS. HAVE MAINTAINED THE IDEA OF
GUSTY WINDS AND HEAVY RAIN AS THE PRIMARY THREATS.
THE ACTIVITY WINDS DOWN BY MID EVENING IN THE ST LAWRENCE VALLEY
TO JUST AFTER MIDNIGHT IN EASTERN VERMONT. DEPENDING ON HOW MUCH
CLEARING WE GET, WE COULD HAVE A BIT OF PATCHY FOG LATE TONIGHT.
THE COOLER AIR LAGS THE WEATHER A BIT, SO IT WILL STILL BE A MUGGY
NIGHT WITH LOWS IN THE 60S.
&&
.SHORT TERM /8 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 355 PM EDT TUESDAY...IT WILL BE A QUIET 48 HOURS. SHORT TERM
MODELS IN PRETTY GOOD AGREEMENT WITH REGARD TO RIDGING OVER THE REGION.
DAILY SPECIFICS...
WEDNESDAY: FLOW TURNS NORTHWEST DURING THE MORNING. 850MB
TEMPERATURES FALL TO 11-12C WHICH WILL SUPPORT HIGH TEMPERATURES
IN THE MID-UPPER 70S. WITH SOME WEAK COLD-AIR ADVECTION AND A GOOD
DEAL OF SUN, WE`LL HAVE SOME EXCELLENT MIXING DURING THE
AFTERNOON. WE SHOULD BE ABLE TO TAP SOME OF THE 20KT OR SO OF WIND
THAT WILL BE A FEW THOUSAND FEET UP, SO IT SHOULD GET A LITTLE
BREEZY IN THE AFTERNOON.
WEDNESDAY NIGHT: HIGH PRESSURE OVERHEAD. CLEAR AND CALM, SO PATCHY
FOG LOOKS LIKE A GOOD BET, ESPECIALLY SINCE THE GROUND WILL STILL
BE A BIT DAMP FROM THE RAIN THIS EVENING. TEMPERATURES MAINLY IN
THE 50S, THOUGH UPPER 40S POSSIBLE IN COLD SPOTS LIKE SARANAC LAKE.
THURSDAY: SHORTWAVE RIDGING AND SURFACE HIGH PRESSURE STILL NEARLY
OVERHEAD, BUT STARTING TO PUSH EAST OF THE AREA. 850MB
TEMPERATURES UP TO 12-13C, WHICH SUPPORTS UPPER 70S TO LOW 80S FOR
HIGHS. PLENTY OF SUN AS WELL.
THURSDAY NIGHT: DISCARDED THE NAM AS IT SEEMS TOO AGRESSIVE WITH
THE LEADING EDGE OF WARM AIR ADVECTION AND PRODUCES THICKENING
CLOUDS AND EVEN SOME LIGHT SHOWERS. THINK IT WILL REMAIN MOSTLY
CLEAR AND DRY PER OTHER MODELS. HOWEVER WITH SOUTHWEST FLOW
DEVELOPING, IT WON`T BE AS COLD, LOTS OF 50S AND EVEN LOW 60S FOR
LOWS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 350 PM EDT TUESDAY...EXTENDED PERIOD REMAINS PREDOMINATELY
QUIET...LARGELY DOMINATED BY HIGH PRESSURE STARTING THE LATTER
PART OF THE WEEKEND...BUT WET TO BEGIN. FOR THE START OF THE
PERIOD...RISING HEIGHTS AND WARMING TEMPERATURES CONTINUE FRIDAY
AS AN UPPER RIDGE CRESTS OVER THE NORTHEAST IN ADVANCE OF OUR NEXT
SURFACE FRONT. MEAN 925MB TEMPS OF +20-23C WILL SUPPORT HIGHS WELL
ABOVE NORMAL FOR EARLY SEPTEMBER WITH WIDESPREAD 80`S EXPECTED.
IT`LL BE MUGGY TOO WITH DEWPOINTS RANGING THROUGH THE 60S WHICH
WILL CREATE AMPLE SURFACE INSTABILITY TO SUPPORT SHOWER AND
THUNDERSTORM DEVELOPMENT ALONG/AHEAD OF THE AFOREMENTIONED FRONT
WHICH WILL SHIFT INTO THE BTV CWA LATE IN THE DAY AND THROUGH THE
EVENING. STILL LOOKS LIKE THE BEST UPPER DYNAMICS PASSES TO OUR
NORTH...WITH THE SURFACE BOUNDARY PARALLEL WITH UPPER FLOW
SUPPORTING THE IDEA OF A SLOW EASTWARD PROGRESSION WHICH IS
MAINTAINED BY THE LATEST ECMWF. GFS REMAINS A BIT FASTER PUSHING
THE BOUNDARY THROUGH THE CWA BY SATURDAY MORNING SO HAVE CONTINUED
ON WITH THE PREVIOUS FORECAST THINKING LEANING TOWARDS THE ECMWF.
BY LATE SATURDAY TREND WILL BE TOWARDS CLEARER AND DRIER WEATHER AS
THE UPPER FLOW TURNS ZONAL AND SURFACE HIGH PRESSURE BUILDS
EASTWARD OUT OF THE CENTRAL CONUS. THIS HIGH THEN SLOWLY SHIFTS EAST
THROUGH THE NORTHEAST AND OFF INTO THE CANADIAN MARITIMES BY LATE
TUESDAY OFFERING A NICE STRETCH OF LATE SUMMER WEATHER. TEMPS RETURN
TO MORE SEASONABLE LEVELS TO MAYBE SLIGHTLY BELOW NORMAL WITH
EXPECTED HIGHS SATURDAY THROUGH TUESDAY IN THE UPPER 60S TO LOW
70S...AND LOWS IN THE MID 40S TO LOW 50S.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
THROUGH 12Z WEDNESDAY...CURRENT VFR ACROSS THE AREA WILL
DETERIORATE TO VARIABLE FLIGHT CONDITIONS AS SHOWERS AND
THUNDERSTORMS DEVELOP ALONG/AHEAD OF A COLD FRONT AND MOVE ACROSS
THE AREA THIS AFTERNOON THROUGH MIDNIGHT. CIGS WILL PRIMARILY
REMAIN VFR BUT VSBY WILL BE REDUCED TO MVFR/IFR AS STORMS PASS.
AFTER 06Z...PRECIP IS EAST OF THE REGION LEAVING GENERALLY CLOUDY
SKIES. CIGS OVERNIGHT WILL GENERALLY BE VFR AT KMSS/KPBG/KBTV...BUT
MVFR AT KRUT/KSLK/KMPV WITH POSSIBLE IFR AT KRUT UNDER BLOCKED
FLOW. AFTER 12Z...ALL CIGS LIFT TO VFR WITH SCT-BKN DIURNAL
STRATOCUMULUS EXPECTED THROUGH THE DAY.
OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY...
18Z WED - 00Z SAT...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG
POSSIBLE...ESPECIALLY AT KMPV/KSLK.
00Z SAT - 00Z SUN...POSSIBLE MVFR AND BRIEF IFR IN SCATTERED SHOWERS
AND THUNDERSTORMS.
00Z SUN - 00Z MON...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG
POSSIBLE...ESPECIALLY AT KMPV/KSLK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...NASH
NEAR TERM...NASH
SHORT TERM...NASH
LONG TERM...LAHIFF
AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
133 PM EDT TUE SEP 2 2014
.SYNOPSIS...
EXPECT SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND TONIGHT ACROSS
MUCH OF THE NORTH COUNTRY AS A COLD FRONT MOVES INTO THE REGION.
SOME OF THE STORMS WILL HAVE THE POTENTIAL TO PRODUCE GUSTY WINDS,
HEAVY DOWNPOURS AND POSSIBLY SMALL HAIL. THE COLD FRONT EXITS THE
REGION TONIGHT AND SLIGHTLY COOLER AND DRIER WEATHER IS EXPECTED
FOR WEDNESDAY AND THURSDAY AS HIGH PRESSURE BUILDS INTO THE
REGION.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 130 PM EDT TUESDAY...EARLY AFTERNOON REFRESH FEATURES SLIGHT
UPWARD MODIFICATIONS IN TEMPERATURES (ALREADY 87F HERE AT BTV) AND
A SLIGHT FINE TUNING OF THE POP/WEATHER EVOLUTION FOR THE NEXT 12
HOURS. OTHERWISE THE OVERALL SCENARIO FOR A LINE OF THUNDERSTORMS
TO DEVELOP IN THE NEXT FEW HOURS AND ROLL FROM WEST TO EAST ACROSS
THE FORECAST AREA IS STILL UNCHANGED.
LAPS SHOWS DECENT AMOUNT OF SURFACE INSTABILITY WITH TEMPERATURES
WELL INTO THE 80S AND DEWPOINTS PUSHING 70F IN MANY AREAS. CAPE
VALUES UP AROUND 1500 J/KG. FROM THE LOOK OF THE CLOUDS AND
RELATIVE LACK OF DEVELOPMENT CURRENTLY ON RADAR OVER NORTHERN NY
AND MOST OF VERMONT, IT APPEARS THERE IS STILL A WEAK CAP AND DRY
AIR ALOFT (THAT SHOWED ON 12Z SOUNDINGS).
HOWEVER, LOOKING FARTHER TO THE WEST OVER ONTARIO SHOWS WHAT IS
HEADING THIS WAY.
6KM LOCAL WRF MODEL AND 15Z HRRR ARE PRETTY CLOSE IN THE OVERALL
EVOLUTION, AND BOTH SEEM REASONABLE. HAVE LEANED TOWARD THEIR
OUTPUT FOR POPULATING THE GRIDS. IF ANYTHING, THEY (AS TYPICAL)
MIGHT BE AN HOUR OR TWO TOO SLOW IN TIMING.
WE SHOULD SEE THE STORMS TO THE WEST CONTINUE TO EVOLVE INTO A
SEMI-CONTINUOUS LINE. THESE STORMS SHOULD REACH THE ST LAWRENCE
VALLEY ABOUT 20Z, THE CHAMPLAIN VALLEY ABOUT 22-23Z AND THEN INTO
EASTERN VERMONT BY 01Z. THINK PRIMARY THREAT REMAINS GUSTY WINDS
(THANKS TO MODERATE WINDS ALOFT AND THE DRY AIR AT MID LEVELS
WHICH COULD ENHANCE DOWNBURST POTENTIAL) ALONG WITH HEAVY RAIN
(GUIDANCE SUGGEST PRECIPITABLE WATER VALUES APPROACH 2". SHOULD
NOT BE AN OVER THE TOP SEVERE WEATHER DAY, BUT IT WILL BE A BIT
BUSY LATER THIS AFTERNOON INTO THE EARLY EVENING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY/...
AS OF 421 AM EDT TUESDAY...SHOWERS AND STORMS SHOULD END FROM WEST
TO EAST ACROSS THE AREA TONIGHT WITH ACTIVITY EXITING MOST OF THE
AREA AFTER MIDNIGHT. WESTERLY FLOW ALOFT THEN DEVELOPS FOR WEDNESDAY
AND THURSDAY AND HIGH PRESSURE BUILDS IN FROM THE WEST. THIS WILL
KEEP THE FORECAST DRY DURING THIS PERIOD AND WITH HIGH PRESSURE
BUILDING IN FROM THE WEST AND NOT THE NORTHWEST...COLDER AIR WILL
NOT MAKE IT INTO THE REGION. SO EVEN THOUGH CONDITIONS WILL BE
COOLER THAN THE PAST COUPLE OF DAYS...HIGH TEMPERATURES WILL BE AT
OR SLIGHTLY ABOVE SEASONAL NORMALS WITH READINGS IN THE 70S TO
AROUND 80.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 410 AM EDT TUESDAY...FORECAST AREA PREDOMINANTLY UNDER
WESTERLY UPPER LEVEL FLOW WITH EASTERN US RIDGE NOSING INTO NEW
ENGLAND EARLY IN THE EXTENDED PERIOD...FOLLOWED BY LOWERING
HEIGHTS AND BROAD TROUGH ESTABLISHED FROM THE WEEKEND ONWARD.
GENERALLY QUIET WEATHER DURING THE EXTENDED PERIOD EXPECT FOR
FRONTAL PASSAGE FOR THE WEEKEND BRINGING CHANCES FOR RAIN.
RISING HEIGHTS AND WARMING TEMPERATURES THURSDAY INTO FRIDAY AS
RIDGE BUILDS INTO THE NORTHEAST IN ADVANCE OF NEXT SURFACE FRONT.
BY FRIDAY...850 MB TEMPS HIT THE UPPER TEENS...WHICH WOULD SUPPORT
VERY WARM HIGHS IN THE MID TO UPPER 80S...A GOOD 10 DEGREES ABOVE
NORMAL. GIVEN 850 MB TEMPS...ADJUSTED MAX TEMPS ON FRIDAY UP A
DEGREE OR TWO ABOVE GUIDANCE.
500 MB TROUGH AND ASSOCIATED SURFACE FRONT MOVES ACROSS THE NORTHERN
US TIER STATES THROUGH MID WEEK...THEN LIFTS NORTH ACROSS CENTRAL
QUEBEC LATE IN THE WEEK INTO THE WEEKEND. TRAILING COLD FRONT ENTERS THE
SAINT LAWRENCE VALLEY LATE FRIDAY AND MOVES THROUGH THE FORECAST
AREA OVER THE WEEKEND. WITH BEST UPPER DYNAMICS AND SURFACE LOW
PASSING TO NORTH...SURFACE BOUNDARY SLOWS AND BECOMES ORIENTED
MORE NORTHEAST TO SOUTHWEST...PARALLEL WITH UPPER FLOW. MODEL
DIFFERENCES BECOME APPARENT LATE SATURDAY INTO SUNDAY...WITH GFS
MOVING THE SURFACE BOUNDARY AND PRECIPITATION TO THE NEW ENGLAND
COAST...WHILE ECMWF HANGS IT UP IN INTERIOR NEW ENGLAND. HEDGED
TOWARD THE ECMWF SOLUTION AND KEPT CHANCE POPS INTO SUNDAY. RIGHT
NOW SATURDAY HAS THE BEST CHANCES FOR RAIN AND THUNDER...
COINCIDING FRONTAL PASSAGE WITH MAX DAYTIME HEATING. TEMPERATURES
DO RETURN TO SEASONAL NORMALS FOR THE WEEKEND WITH FRONTAL PASSAGE
AND LOWER HEIGHTS AS THE EASTERN RIDGE IS SUPPRESSED.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THROUGH 12Z WEDNESDAY...CURRENT VFR ACROSS THE AREA WILL
DETERIORATE TO VARIABLE FLIGHT CONDITIONS AS SHOWERS AND
THUNDERSTORMS DEVELOP ALONG/AHEAD OF A COLD FRONT AND MOVE ACROSS
THE AREA THIS AFTERNOON THROUGH MIDNIGHT. CIGS WILL PRIMARILY
REMAIN VFR BUT VSBY WILL BE REDUCED TO MVFR/IFR AS STORMS PASS.
AFTER 06Z...PRECIP IS EAST OF THE REGION LEAVING GENERALLY CLOUDY
SKIES. CIGS OVERNIGHT WILL GENERALLY BE VFR AT KMSS/KPBG/KBTV...BUT
MVFR AT KRUT/KSLK/KMPV WITH POSSIBLE IFR AT KRUT UNDER BLOCKED
FLOW. AFTER 12Z...ALL CIGS LIFT TO VFR WITH SCT-BKN DIURNAL
STRATOCUMULUS EXPECTED THROUGH THE DAY.
OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY...
18Z WED - 00Z SAT...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG
POSSIBLE...ESPECIALLY AT KMPV/KSLK.
00Z SAT - 00Z SUN...POSSIBLE MVFR AND BRIEF IFR IN SCATTERED SHOWERS
AND THUNDERSTORMS.
00Z SUN - 00Z MON...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG
POSSIBLE...ESPECIALLY AT KMPV/KSLK.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...NASH
SHORT TERM...EVENSON
LONG TERM...HANSON
AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1247 PM EDT TUE SEP 2 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE ACROSS THE AREA TODAY EXTENDING FROM LOW
PRESSURE TRACKING NORTHEAST ACROSS QUEBEC. HIGH PRESSURE WILL
EXPAND OVER THE OHIO VALLEY TONIGHT...THEN TO THE EAST COAST ON
WEDNESDAY. A WARM FRONT WILL LIFT NORTH ON THURSDAY AHEAD OF THE
NEXT LOW PRESSURE SYSTEM THAT WILL PASS NORTH OF THE GREAT LAKES
ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LINE OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS PUSHING INTO
NORTHWEST OHIO AT THIS TIME WITH THE COLD FRONT. STILL EXPECTING
SOME SUN BEHIND THE FRONT ONCE IT MOVES THROUGH THE REGION.
DECIDED TO BUMP TEMPERATURES DOWN A FEW DEGREES DUE TO EXTENSIVE
CLOUD COVER AND COOL AIR ADVECTION BEHIND THE FRONT.
OTHERWISE...NO SIGNIFICANT CHANGES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
HIGH PRESSURE WILL EXPAND EASTWARD ACROSS THE OHIO VALLEY TONIGHT.
IT LOOKS LIKE A WEAK THERMAL TROUGH WILL LINGER OVER LAKE ERIE ON
THE NORTH SIDE OF THE HIGH THIS EVENING AND MAY PROVIDE ENOUGH
CONVERGENCE FOR A FEW SHOWERS TO DEVELOP OVER THE LAKE. LEFT A LOW
POP BOTH OVER THE LAKE AND ALONG THE EASTERN LAKESHORE FOR A PORTION
OF THE NIGHT. INLAND AREAS...ESPECIALLY OUR SOUTHERN COUNTIES COULD
SEE SOME FOG OR STRATUS GIVEN THE LINGERING BOUNDARY LAYER MOISTURE
COUPLED WITH CLEARING SKIES AND LIGHT WINDS. TEMPERATURES WILL
BOTTOM OUT IN THE UPPER 50S TO LOW 60S.
THE AIR MASS DOES NOT COOL MUCH WITH THE FRONTAL PASSAGE AND
TEMPERATURES ARE STILL EXPECTED TO BE A COUPLE DEGREES ABOVE NORMAL
ON WEDNESDAY. THE MAIN DIFFERENCE WILL BE FELT IN THE HUMIDITY WHICH
WILL BE LOWER AND MORE PLEASANT WITH DEW POINTS NEAR 60 DEGREES.
MAINLY JUST SCATTERED CU ON WEDNESDAY ONCE ANY MORNING CLOUDS BURN
OFF.
HEIGHTS WILL REBOUND OVER THE AREA ON THURSDAY AND A WARM FRONT WILL
LIFT NORTH AHEAD OF THE NEXT LOW PRESSURE SYSTEM TRACKING OUT OF THE
PLAINS. THIS SYSTEM IS FORECAST TO TRACK ACROSS LAKE SUPERIOR THEN
CONTINUE NORTHEAST ACROSS ONTARIO AND QUEBEC. ENOUGH DRY AIR SHOULD
STILL BE IN PLACE ON THURSDAY FOR THE FORECAST AREA TO STAY DRY.
LEFT THE 20 POP IN THE FORECAST ON THURSDAY NIGHT AS MOISTURE DOES
START TO INCREASE ALTHOUGH THE MORE FOCUSED MOISTURE ADVECTION WILL
BE WELL TO THE NORTH. THE ASSOCIATED COLD FRONT WILL SINK SOUTH
TOWARDS THE AREA ON FRIDAY. LOWERED POPS DURING THE MORNING HOURS
AND ACROSS THE SOUTHERN COUNTIES THAT SHOULD STRUGGLE TO SEE ANY
PRECIPITATION UNTIL FRIDAY NIGHT. TEMPERATURES ON THURSDAY AND
FRIDAY WILL BE IN THE MID 80S...WITH A FEW SPOTS MAKING A RUN AT THE
UPPER 80S.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
NO BIG CHANGES TO THE MODELS FOR THE EXTENDED WITH GUIDANCE SHOWING
A COLD FRONT TO OUR SOUTH SATURDAY MORNING WITH DRIER AIR AND HIGH
MOVING IN FROM THE NORTH. DONT THINK THE DAY WILL BEGIN DRY HOWEVER
AS THE ECMWF REMAINS SLOWER THAN THE GFS IN MOVING MOISTURE OUT OF
THE AREA. WILL CONTINUE WITH CHANCE POPS THROUGH THE MORNING
SATURDAY BEFORE DROPPING TO A SLIGHT CHANCE ACROSS THE NORTH.
SATURDAY NIGHT THROUGH MONDAY LOOK DRY. TEMPS NEAR NORMAL AFTER AN
ABOVE NORMAL END TO THE WEEK.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
WEAK COLD FRONT TO OUR NORTHWEST NR A KFNT-KSBN LINE. FROM WILL
MOVE THROUGH THE AREA DURING THE DAY. CONVECTION FROM INDIANA
TRACKING ENE ACROSS CENTRAL AND SRN OHIO. WILL LIKELY SEE THUNDER
INTO NRN OHIO BUT KEPT MENTION OUT OF THE FAR NRN TAFS. HRRR MOVES
THIS PRECIP THROUGH DURING THE MORNING AND EARLY AFTERNOON WITH
POSSIBLY A FEW LINGERING SHOWERS FOR MID AFTERNOON. EXPECT MAINLY
MVFR CONDITIONS WITH AND JUST BEHIND THE PRECIP...LIFTING TO VFR 2
TO 4 HOURS AFTER PRECIP ENDS. EXPECT THE EVENING WILL BEGIN VFR
HOWEVER WITH LOW LEVEL MOISTURE IN PLACE...DRYING ALOFT AND HIGH
PRESSURE OVER THE AREA EXPECT MVFR AND POSSIBLY IFR CIGS/FOG TO
DEVELOP OVERNIGHT.
OUTLOOK...NON VFR LIKELY IN SHOWERS AND THUNDERSTORMS BY FRIDAY
EVENING INTO SATURDAY WITH THE NEXT COLD FRONT.
&&
.MARINE...
WILL BEGIN TODAY CLOSE TO SMALL CRAFT CRITERIA MAINLY EAST OF
CONNEAUT BUT FOR NOW WILL CONTINUE WITH A FORECAST JUST BELOW. WINDS
TODAY WILL BE FROM THE SOUTHWEST AHEAD OF A WEAK COLD FRONT DUE IN
LATE MORNING/EARLY AFTERNOON. WINDS WILL TURN WEST TO BRIEFLY
NORTHWEST BEHIND THE BOUNDARY. HIGH PRESSURE BUILDS IN TONIGHT AND
WEDNESDAY. THURSDAY THE HIGH WILL DRIFT EAST AND A LOW WILL BE
MOVING THROUGH THE NORTHERN PLAINS. THIS WILL AGAIN SETUP SOUTHWEST
FLOW ON THE LAKE THURSDAY INCREASING TO 10 TO 20 KNOTS. THE LOW WILL
MOVE THROUGH EASTERN CANADA FRIDAY DRAGGING A COLD FRONT ACROSS THE
LAKE DURING THE AFTERNOON. WINDS WILL TURN NORTHWEST FRIDAY NIGHT
AND SATURDAY BEHIND THE FRONT. ALTHOUGH CLOSE...NO NEAR TERM
HEADLINES FOR NOW. FRIDAY INTO SATURDAY WE COULD REACH SMALL CRAFT
CRITERIA AS WINDS TURN NORTHWEST.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...LOMBARDY
SHORT TERM...KEC
LONG TERM...TK
AVIATION...TK
MARINE...TK
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
531 PM CDT TUE SEP 2 2014
.UPDATE...
THUNDERSTORMS HAVE DEVELOPED OVER THE WESTERN AND CENTRAL SOUTH
PLAINS...A BIT SOUTH OF PREVIOUS BEST-GUESS...BUT GIVE SHORT TERM
SOLUTIONS SOME CREDIT. WE HAVE UPDATED FOR LOW COVERAGE THUNDER
THROUGH EARLY THIS EVENING. 1500-2000 JOULES PER KILOGRAM OF
CONVECTIVE ENERGY BUT VERY LITTLE SHEAR CONTRIBUTING TO BRIEF
HEAVY SHOWERS AND BRIEF MOSTLY WEAK HAIL INDICATIONS AT THIS TIME.
ACTIVITY SHOULD TAKE ON BETTER NORTHERLY DRIFT...THOUGH BELIEVE
MOST ACTIVITY WILL RELENT BY DARK. RMCQUEEN
&&
.PREV DISCUSSION... /ISSUED 306 PM CDT TUE SEP 2 2014/
SHORT TERM...
FOCUS IN THE SHORT TERM IS ON SMALL CHANCE FOR ISOLATED SHOWERS
AND/OR THUNDERSTORMS LATE THIS AFTN AND THIS EVENING. RADAR IS QUIET
ATTM BUT SATELLITE SHOWING AN AREA OF CUMULUS DEVELOPMENT TO THE
EAST AND SOUTHEAST OF LUBBOCK IN AN AREA WHERE OBJECTIVE ANALYSIS
SHOWS ENHANCED INSTABILITY AND WEAKENING INHIBITION. SOME VERY
MODEST LOW LEVEL SPEED CONVERGENCE AND MOISTURE ADVECTION IN THIS
AREA MAY NOT HELP TOO MUCH BUT CERTAINLY WILL NOT HURT. A WEAK
FRONTAL BOUNDARY PULLED UP STATIONARY NEAR A MORTON TO TULIA LINE
WITH WEAK CONFLUENCE IN ITS VICINITY BUT WITH SFC DEW POINTS ABOUT 5
DEGREES LOWER THAN IN THE FORMER AREA. WOULD EXPECT THESE TWO AREAS
HAVE THE BEST CHANCE OF SEEING CONVECTIVE DEVELOPMENT. 12Z WRF-NAM
HIGHLIGHTS THE LATTER WHILE RECENT RUNS OF THE HRRR FEATURES THE
FORMER. EITHER WAY WILL LIKELY BE DIFFICULT TO GENERATE ANYTHING
OTHER THAN SMALL-SCALE AND ISOLATED SHOWERS WITH AREAL COVERAGE NOT
WARRANTING MENTION IN THE ZONE FCST ATTM.
WEDNESDAY SHOULD BE EVEN MORE DIFFICULT TO PRODUCE PRECIP WITH
STRENGTHENING HIGH PRESSURE OVERHEAD AND LOW LEVEL FLOW BECOMING
MORE UNIFORM FROM THE SOUTH. TEMPS TO REMAIN WARMER THAN NORMAL WITH
BOTH LOWS AND HIGHS NEAR WARMER MAV GUIDANCE LOOKING MORE LIKELY
ATTM.
LONG TERM...
ONLY MINOR CHANGES TO THE LONG TERM FORECAST FOR THIS ITERATION...AS
A MUTED COOLING TREND WILL BE FOLLOWED BY A POTENTIALLY WET WEEKEND
FOR PARTS OF THE REGION.
BY WEDNESDAY EVENING...A MOSTLY ZONAL UPPER FLOW REGIME WILL BE IN
PLACE ACROSS THE CONUS...WITH AN ELONGATED UPPER RIDGE IN PLACE
ACROSS MOST OF THE SOUTH...INCLUDING WEST TEXAS. WHILE THIS WILL
CONTINUE TO ENSURE MOSTLY DRY CONDITIONS THROUGH THE END OF THE WORK
WEEK...GRADUALLY DROPPING 1000-500 MB THICKNESSES WILL ALLOW
TEMPERATURES TO INCREMENTALLY FALL BACK TO A MORE REASONABLE UPPER
80S ON THE SOUTH PLAINS TO MID 90S ON THE ROLLING PLAINS.
BY LATE IN THE WEEK AND THROUGH THE WEEKEND...A BROAD UPPER TROUGH
WILL PUSH EASTWARD ACROSS THE NORTHERN CONUS...SENDING A
MODEST COLD FRONT SOUTHWARD THROUGH THE CENTRAL PLAINS AND AT LEAST
THE TEXAS PANHANDLE. MEANWHILE DEEPER MONSOONAL MOISTURE...POSSIBLY
WITH A CONNECTION TO REMNANTS OF TROPICAL STORM DOLLY...WILL BE
DRAWN NORTHWARD INTO THE SOUTHWEST AND EVENTUALLY EASTWARD AS IT
GETS CAUGHT IN THE WESTERLY UPPER FLOW ASSOCIATED WITH THE
PREVIOUSLY MENTIONED TROUGH. ALL OF THIS IS EXPECTED TO RESULT IN
INCREASING RAIN CHANCES BEGINNING AS EARLY AS LATE FRIDAY...AND
POSSIBLY LASTING THROUGH LATE SUNDAY DEPENDING ON A FEW FACTORS.
THE MOST PROMINENT OF THESE FACTORS SEEMS TO BE THE TIMING AND
STRENGTH OF THE APPROACHING COLD FRONT...AS THE GFS AND ECMWF REMAIN
ABOUT 24 HOURS APART IN THIS REGARD. THE GFS INDICATES A
SLOWER...WEAKER FRONT REACHING THE NORTHERN BORDER OF THE CWA LATE
SATURDAY AFTERNOON AND WASHING OUT ACROSS THE CWA SUNDAY.
MEANWHILE...THE ECMWF SOLUTION BRINGS THIS FRONT INTO THE AREA AS
EARLY AS LATE FRIDAY...AND PUSHES THE BOUNDARY WELL THROUGH THE CWA
BY LATE SATURDAY. THE LATTER SOLUTION NOT SURPRISINGLY DEVELOPS THE
HEAVIEST PRECIPITATION DURING THE LATE FRIDAY THROUGH SATURDAY
TIME FRAME...WHILE THE GFS SEEMS TO BE FOCUSING ON THE LATE SATURDAY
THROUGH LATE SUNDAY TIME FRAME. GIVEN THAT THE BOUNDARY WILL BE WELL
REMOVED FROM ITS PARENT TROUGH BY THE TIME IT REACHES THIS
LATITUDE...WE WILL CONTINUE TO SIDE WITH THE SLOWER GFS SOLUTION AND
HIGHLIGHT LATE SATURDAY WITH THE HIGHEST POPS. LIKEWISE...LOW END POPS
WERE ALSO EXTENDED THROUGH SUNDAY EVENING GIVEN THAT IN THIS SLOWER
SCENARIO REMNANTS OF THIS BOUNDARY AND AMPLE MOISTURE WOULD LIKELY
LINGER THROUGH THIS PERIOD. HOWEVER...UNCERTAINTIES REGARDING
FRONTAL TIMING AND STRENGTH ARE COMPOUNDED FURTHER ON SUNDAY WITH
THE POSSIBILITY OF LINGERING NOCTURNAL CONVECTION AND STABILIZING
OUTFLOWS.
BY MONDAY...THE UPPER RIDGE IS EXPECTED TO SLIGHTLY AMPLIFY ACROSS
THE SOUTHERN PLAINS WHILE THE COLUMN DRIES CONSIDERABLY. THIS
SHOULD TAPER OFF PRECIPITATION CHANCES UNTIL LATER IN THE WEEK WHEN
ANOTHER POSSIBLY STRONGER COLD FRONT MOVES THROUGH THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 92 62 90 62 / 10 0 10 10 10
TULIA 68 93 66 91 66 / 20 0 10 0 10
PLAINVIEW 68 93 66 90 66 / 20 0 0 0 10
LEVELLAND 66 92 66 90 67 / 20 0 10 10 0
LUBBOCK 72 93 68 92 67 / 20 0 0 10 0
DENVER CITY 66 91 66 89 66 / 20 0 10 10 10
BROWNFIELD 68 93 67 90 67 / 20 0 0 10 0
CHILDRESS 75 97 75 96 72 / 10 0 0 0 0
SPUR 73 97 72 94 71 / 10 0 0 10 10
ASPERMONT 76 99 74 96 73 / 0 0 0 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/99
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
306 PM CDT TUE SEP 2 2014
.SHORT TERM...
FOCUS IN THE SHORT TERM IS ON SMALL CHANCE FOR ISOLATED SHOWERS
AND/OR THUNDERSTORMS LATE THIS AFTN AND THIS EVENING. RADAR IS QUIET
ATTM BUT SATELLITE SHOWING AN AREA OF CUMULUS DEVELOPMENT TO THE
EAST AND SOUTHEAST OF LUBBOCK IN AN AREA WHERE OBJECTIVE ANALYSIS
SHOWS ENHANCED INSTABILITY AND WEAKENING INHIBITION. SOME VERY
MODEST LOW LEVEL SPEED CONVERGENCE AND MOISTURE ADVECTION IN THIS
AREA MAY NOT HELP TOO MUCH BUT CERTAINLY WILL NOT HURT. A WEAK
FRONTAL BOUNDARY PULLED UP STATIONARY NEAR A MORTON TO TULIA LINE
WITH WEAK CONFLUENCE IN ITS VICINITY BUT WITH SFC DEW POINTS ABOUT 5
DEGREES LOWER THAN IN THE FORMER AREA. WOULD EXPECT THESE TWO AREAS
HAVE THE BEST CHANCE OF SEEING CONVECTIVE DEVELOPMENT. 12Z WRF-NAM
HIGHLIGHTS THE LATTER WHILE RECENT RUNS OF THE HRRR FEATURES THE
FORMER. EITHER WAY WILL LIKELY BE DIFFICULT TO GENERATE ANYTHING
OTHER THAN SMALL-SCALE AND ISOLATED SHOWERS WITH AREAL COVERAGE NOT
WARRANTING MENTION IN THE ZONE FCST ATTM.
WEDNESDAY SHOULD BE EVEN MORE DIFFICULT TO PRODUCE PRECIP WITH
STRENGTHENING HIGH PRESSURE OVERHEAD AND LOW LEVEL FLOW BECOMING
MORE UNIFORM FROM THE SOUTH. TEMPS TO REMAIN WARMER THAN NORMAL WITH
BOTH LOWS AND HIGHS NEAR WARMER MAV GUIDANCE LOOKING MORE LIKELY
ATTM.
&&
.LONG TERM...
ONLY MINOR CHANGES TO THE LONG TERM FORECAST FOR THIS ITERATION...AS
A MUTED COOLING TREND WILL BE FOLLOWED BY A POTENTIALLY WET WEEKEND
FOR PARTS OF THE REGION.
BY WEDNESDAY EVENING...A MOSTLY ZONAL UPPER FLOW REGIME WILL BE IN
PLACE ACROSS THE CONUS...WITH AN ELONGATED UPPER RIDGE IN PLACE
ACROSS MOST OF THE SOUTH...INCLUDING WEST TEXAS. WHILE THIS WILL
CONTINUE TO ENSURE MOSTLY DRY CONDITIONS THROUGH THE END OF THE WORK
WEEK...GRADUALLY DROPPING 1000-500 MB THICKNESSES WILL ALLOW
TEMPERATURES TO INCREMENTALLY FALL BACK TO A MORE REASONABLE UPPER
80S ON THE SOUTH PLAINS TO MID 90S ON THE ROLLING PLAINS.
BY LATE IN THE WEEK AND THROUGH THE WEEKEND...A BROAD UPPER TROUGH
WILL PUSH EASTWARD ACROSS THE NORTHERN CONUS...SENDING A
MODEST COLD FRONT SOUTHWARD THROUGH THE CENTRAL PLAINS AND AT LEAST
THE TEXAS PANHANDLE. MEANWHILE DEEPER MONSOONAL MOISTURE...POSSIBLY
WITH A CONNECTION TO REMNANTS OF TROPICAL STORM DOLLY...WILL BE
DRAWN NORTHWARD INTO THE SOUTHWEST AND EVENTUALLY EASTWARD AS IT
GETS CAUGHT IN THE WESTERLY UPPER FLOW ASSOCIATED WITH THE
PREVIOUSLY MENTIONED TROUGH. ALL OF THIS IS EXPECTED TO RESULT IN
INCREASING RAIN CHANCES BEGINNING AS EARLY AS LATE FRIDAY...AND
POSSIBLY LASTING THROUGH LATE SUNDAY DEPENDING ON A FEW FACTORS.
THE MOST PROMINENT OF THESE FACTORS SEEMS TO BE THE TIMING AND
STRENGTH OF THE APPROACHING COLD FRONT...AS THE GFS AND ECMWF REMAIN
ABOUT 24 HOURS APART IN THIS REGARD. THE GFS INDICATES A
SLOWER...WEAKER FRONT REACHING THE NORTHERN BORDER OF THE CWA LATE
SATURDAY AFTERNOON AND WASHING OUT ACROSS THE CWA SUNDAY.
MEANWHILE...THE ECMWF SOLUTION BRINGS THIS FRONT INTO THE AREA AS
EARLY AS LATE FRIDAY...AND PUSHES THE BOUNDARY WELL THROUGH THE CWA
BY LATE SATURDAY. THE LATTER SOLUTION NOT SURPRISINGLY DEVELOPS THE
HEAVIEST PRECIPITATION DURING THE LATE FRIDAY THROUGH SATURDAY
TIME FRAME...WHILE THE GFS SEEMS TO BE FOCUSING ON THE LATE SATURDAY
THROUGH LATE SUNDAY TIME FRAME. GIVEN THAT THE BOUNDARY WILL BE WELL
REMOVED FROM ITS PARENT TROUGH BY THE TIME IT REACHES THIS
LATITUDE...WE WILL CONTINUE TO SIDE WITH THE SLOWER GFS SOLUTION AND
HIGHLIGHT LATE SATURDAY WITH THE HIGHEST POPS. LIKEWISE...LOW END POPS
WERE ALSO EXTENDED THROUGH SUNDAY EVENING GIVEN THAT IN THIS SLOWER
SCENARIO REMNANTS OF THIS BOUNDARY AND AMPLE MOISTURE WOULD LIKELY
LINGER THROUGH THIS PERIOD. HOWEVER...UNCERTAINTIES REGARDING
FRONTAL TIMING AND STRENGTH ARE COMPOUNDED FURTHER ON SUNDAY WITH
THE POSSIBILITY OF LINGERING NOCTURNAL CONVECTION AND STABILIZING
OUTFLOWS.
BY MONDAY...THE UPPER RIDGE IS EXPECTED TO SLIGHTLY AMPLIFY ACROSS
THE SOUTHERN PLAINS WHILE THE COLUMN DRIES CONSIDERABLY. THIS
SHOULD TAPER OFF PRECIPITATION CHANCES UNTIL LATER IN THE WEEK WHEN
ANOTHER POSSIBLY STRONGER COLD FRONT MOVES THROUGH THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 92 62 90 62 / 10 0 10 10 10
TULIA 68 93 66 91 66 / 10 0 10 0 10
PLAINVIEW 68 93 66 90 66 / 10 0 0 0 10
LEVELLAND 66 92 66 90 67 / 0 0 10 10 0
LUBBOCK 71 93 68 92 67 / 10 0 0 0 0
DENVER CITY 66 91 66 89 66 / 0 0 10 10 10
BROWNFIELD 68 93 67 90 67 / 0 0 0 10 0
CHILDRESS 75 97 75 96 72 / 10 0 0 0 0
SPUR 73 97 72 94 71 / 10 0 0 10 10
ASPERMONT 76 99 74 96 73 / 0 0 0 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07/16
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1257 PM CDT TUE SEP 2 2014
.DISCUSSION...
18Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
LITTLE REGIONAL AIR MASS CHANGE OVER THE NEXT 24-30 HOURS. THE
RESIDENT UNSTABLE AIR MASS WILL REMAIN UNSEASONABLY MOIST THROUGH
THURSDAY. ALTHOUGH MOST CONVECTIVE ACTIVITY WILL REMAIN NORTH OF
THE METRO HUBS TODAY...INCREASING CHANCES FOR MORE WIDESPREAD GULF
PRECIPITATION MOVING INLAND DURING THE EARLY AM WED HOURS WILL
PLACE MORE COASTAL TERMINALS UNDER MODERATE CHANCES FOR SPEED
CONVERGENCE SHRA OR TSRA THROUGH SUNRISE. THUS...THE THINKING IS
THAT MANY TERMINALS WILL EXPERIENCE BRIEF PERIODS OF PASSING
SHOWERS...WITH THAT EVEN SHORTER-LIVED THUNDERSTORM...PASSING
WITHIN THE VICINITY FROM LATE MORNING THROUGH MID-AFTERNOON. 31
&&
.PREV DISCUSSION... /ISSUED 1026 AM CDT TUE SEP 2 2014/
UPDATE...
SEE MORNING UPDATE.
DISCUSSION...
12Z SOUNDINGS SHOW PW VALUES BETWEEN 2.1 AND 2.2 INCHES AND THIS
IS SUPPORTED BY GPS MET DATA, CONVECTIVE TEMPS ARE BETWEEN 86 AND
88 DEGREES TODAY AND THIS THRESHOLD WILL BE MET EASILY. A WELL
DEVELOPED S/WV EXTENDS FROM CENTRAL ARKANSAS INTO CENTRAL TEXAS
WHICH SERVE AS ANOTHER FOCUS FOR SHRA/TSRA. UPPER LEVEL RIDING HAS
INCHED CLOSER TO SE TX WHICH WILL IMPART A BIT OF SUBSIDENCE. THE
RAP IS VERY AGGRESSIVE WITH RAINFALL THIS AFTN WHILE THE
HRRR/ARW-EAST REMAIN MORE BENIGN. THE RAP WAS OVERDONE YESTERDAY
AND DID NOT INITIALIZE ALL THAT WELL SO HAVE LEANED TOWARD A HRRR/WRF
BLEND. CHANCE POPS LOOK APPROPRIATE SO NO CHANGES TO THE POP/WX
GRIDS. DID BUMP MAX T GRIDS UP A FEW DEGREES TO MATCH TRENDS/OBS.
AS FOR TS DOLLY...THE STORM WILL PROBABLY MAKE LANDFALL A BIT
EARLIER...SOMETIME THIS EVENING. THE MAIN EFFECT FOR SE TX WILL BE
INCREASING SWELLS OVER THE OFFSHORE MARINE ZONES AND A 1.0-1.5
FOOT BUMP UP IN TIDE LEVELS. NEW ZONES OUT BY 1030 AM. 43
&&
PREV DISCUSSION... /ISSUED 405 AM CDT TUE SEP 2 2014/
DISCUSSION...
A FEW SHOWERS ARE MOVING NORTHWARD ACROSS THE COASTAL WATERS THIS
MORNING IN ASSOCIATION WITH AN AREA OF DEEPER MOISTURE WHICH IS
APPROACHING THE UPPER TEXAS COAST. FURTHER TO THE SOUTH...TD 5 HAS
STRENGTHENED INTO TROPICAL STORM DOLLY THIS MORNING. THE CENTER OF
THE SYSTEM HAS FORMED A BIT FURTHER NORTH THAT PREVIOUSLY EXPECTED
WHICH HAS CAUSED A CORRESPONDING SHIFT IN THE FORECAST TRACK. THE
ONLY ADDITIONAL IMPACTS TO SOUTHEAST TEXAS WILL BE SOME SLIGHTLY
HIGHER SEAS OFFSHORE AS THE NEW TRACK STILL TAKES THE SYSTEM INTO
MEXICO WELL SOUTH OF THE BORDER.
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP INLAND LATER
THIS MORNING AS MOISTURE STREAMS BACK INTO THE REGION. COVERAGE
SHOULD INCREASE ACROSS OUR NORTHERN COUNTIES LATE THIS AFTERNOON
AS A PASSING SHORTWAVE BRINGS ADDITIONAL LIFT TO THE REGION. GIVEN
THE RICH MOISTURE A FEW BRIEF HEAVY DOWNPOURS WILL BE POSSIBLE
WITH THE ACTIVITY TODAY. HIGH TEMPERATURES SHOULD REMAIN IN THE
LOW TO MID 90S AREAWIDE WITH THE PRECIPITATION AND GREATER CLOUD
COVER.
ONLY SLIGHT CHANGES FOR THE MID TO EXTENDED RANGE FORECAST THIS
MORNING. THE UPPER LEVEL PATTERN OVERHEAD REMAINS RELATIVELY
UNCHANGED THROUGH THE WEEK WITH A BROAD FLAT RIDGE ACROSS THE
SOUTHERN UNITED STATES. THIS WILL ALLOW FOR CONTINUED DIURNALLY
DRIVEN SHOWERS AND THUNDERSTORMS WITH HIGH TEMPERATURES IN THE LOW
TO MID 90S...NEAR THE NORMALS FOR THE FIRST WEEK OF SEPTEMBER. 38
&&
MARINE...
TROPICAL STORM DOLLY IS LOCATED IN THE BAY OF CAMPECHE EARLY
THIS MORNING. BASED ON THE CURRENT FORECAST...DOLLY IS EXPECTED
TO APPROACH THE COAST OF MEXICO BY TONIGHT AND MOVE INLAND BY
WEDNESDAY MORNING. BUILDING SEAS CAN BE EXPECTED ALONG THE UPPER
TEXAS COAST. CAUTION FLAGS ARE CURRENTLY IN EFFECT...AND ADVISORIES
MIGHT BE NEEDED IF SEAS BUILD HIGHER THAN ANTICIPATED. PERIODS OF
SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ACROSS OUR AREA OVER THE
NEXT COUPLE OF DAYS. TOWARD THE END OF THE WEEK...EXPECT WEAKENING
ONSHORE WINDS AND LOWERING SEAS. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 75 95 75 94 75 / 20 20 10 20 10
HOUSTON (IAH) 77 93 76 92 76 / 20 30 10 20 10
GALVESTON (GLS) 81 91 81 90 81 / 20 30 20 20 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 8 PM CDT THIS EVENING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...42
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1232 PM CDT TUE SEP 2 2014
.AVIATION...
THERE REMAINS A SMALL POSSIBILITY OF ISOLATED THUNDER DEVELOPING
NEAR A WEAK FRONTAL BOUNDARY THAT WILL PULL UPSTATIONARY SOUTH OF
A CLOVIS TO AMARILLO LINE. SUPPRESSION FROM UPPER LEVEL HIGH
PRESSURE WILL FOR THE MOST PART HELP THE CAPPING INVERSION REMAIN
STRONG...BUT MODELS STILL HAVE A WEAK SIGNAL OF SOME CONVECTION
DEVELOPING IN AN AREA OF LOW LEVEL CONVERGENCE NEAR THE BOUNDARY.
LONG STORY SHORT IS COVERAGE WILL BE VERY LIMITED...IF ANY AT
ALL...AND WILL KEEP OUT OF BOTH TAFS.
OTHER ITEM OF NOTE IS THE POSSIBILITY OF STRATUS MAKING A RUN INTO
THE FCST AREA LATE TONIGHT. WILL GET THE BALL ROLLING BY INSERTING
A TEMPO MVFR MENTION IN THE KLBB TAF.
&&
.PREV DISCUSSION... /ISSUED 639 AM CDT TUE SEP 2 2014/
AVIATION...
SOUTHERLY SURFACE WINDS AND VFR CONDITIONS SHOULD PREVAIL OVER
MOST OF THE NEXT 24 HOURS. HOWEVER...THERE IS A SMALL CHANCE OF
-TSRA IN THE VICINITY OF EITHER TERMINAL BETWEEN ABOUT 20 UTC AND
03 UTC. IN ADDITION...A WEAK FRONT COULD PRODUCE A TEMPORARY WIND
SHIFT AT KCDS AROUND 14-15 UTC...BUT CONFIDENCE IS VERY LOW.
PREV DISCUSSION... /ISSUED 355 AM CDT TUE SEP 2 2014/
SHORT TERM...
3 AM TEMPS WERE STILL IN THE LOWER 80S ACROSS MUCH OF THE SOUTHERN
SOUTH PLAINS INTO THE ROLLING PLAINS...WHICH ISN/T SURPRISING GIVEN
THE RECORD-SETTING WARMTH ACROSS THE AREA ON LABOR DAY. A WEAK COLD
FRONT WAS LOCATED NEAR I-40...AND THERE WAS EVEN AN AREA OF LOW
CLOUDS DEVELOPING NORTH OF THE FRONT ACROSS THE OKLA AND NRN TX
PANHANDLES. ALOFT...A SHORTWAVE TROUGH IS MOVING FROM THE CENTRAL
PLAINS INTO THE MIDWEST...WITH ONLY A WEAK REFLECTION INTO THE SRN
HIGH PLAINS. THE FRONT IS EXPECTED TO MAKE SOME SWD PROGRESS THIS
MORNING ACROSS THE WEST BEFORE STALLING/WASHING OUT THIS
AFTERNOON...WITH A WEAK SURFACE LOW DEVELOPING ACROSS THE WESTERN
SPLNS. THIS IN TURN SHOULD PRODUCE A WEAKLY CONVERGENT ZONE FROM THE
CENTRAL SPLNS TO THE SOUTH-CENTRAL TX PANHANDLE...ALONG WITH A
DIFFUSE DRYLINE. WITH LITTLE IF ANY UPPER-LEVEL SUPPORT...WE/LL HAVE
TO RELY ON SURFACE-BASED LIFT TO GENERATE ANY MOIST CONVECTION
TODAY. KLBB FCST SOUNDING SHOWS A WEAKLY CAPPED PROFILE THIS
AFTERNOON...WITH NO CAP REMAINING FARTHER TO THE NORTH-NORTHEAST.
THERE IS NOT A WHOLE LOT OF QPF SIGNAL IN MODEL SOLUTIONS...BUT THE
06 UTC HRRR AND RAP RUNS INDICATE ISOLATED DEVELOPMENT AS WELL AS
THE SREF...WHICH SOMEWHAT BULLSEYES THE CAPROCK CANYONS AREA. WE
WILL RUN WITH A 15-20 PERCENT CHANCE OF T-STORMS...CENTERED ACROSS
BRISCOE COUNTY...AND ROUGHLY EXTENDING WEST TO I-27 AND SOUTH TO
NEAR HWY 82. SHEAR APPEARS TO BE TOO WEAK TO SUPPORT MORE THAN
PULSE-TYPE NON-SEVERE STORMS...BUT ML CAPES NEARING 2000 J/KG COULD
SUPPORT SMALL HAIL...LOCALIZED WIND GUSTS TO 50 MPH...AND A BRIEF
DOWNPOUR. STORMS SHOULD DIMINISH QUICKLY THIS EVENING WITH THE LOSS
OF SFC-BASED INSTABILITY. SKIES SHOULD BE MOSTLY CLEAR TONIGHT
ALTHOUGH SOME LOW STRATUS COULD INVADE FROM THE SOUTH EARLY WED
MORNING.
AS FOR TEMPS...FORTUNATELY WE SHOULD SEE THE HEAT OF THE PAST TWO
DAYS BACK DOWN A BIT...ALTHOUGH WE WOULDN/T BE SURPRISED TO SEE A
FEW LOCATIONS HIT 100 DEGREES IN THE LOW ROLLING PLAINS. HIGH TEMPS
MAY ONLY REACH THE LOWER 90S IN THE FAR SW TX PANHANDLE DUE TO THE
WEAK FRONT/S INFLUENCE...WITH MIDDLE TO UPPER 90S EXPECTED ELSEWHERE.
LONG TERM...
THE EXTENDED FORECAST FEATURES A WELCOME COOLING TREND EARLY ON WITH
INCREASING RAIN CHANCES BY THE WEEKEND.
INITIALLY...THE WESTERN EXTENT OF A LONGITUDINALLY BROAD UPPER RIDGE
WILL HOLD SWAY OVER WEST TEXAS MID/LATE WEEK. THIS RIDGE WILL
PROVIDE DRY AND WARM WEATHER...THOUGH DECREASING 1000-500 MB
THICKNESSES AND 850 MB TEMPERATURES PROMISE A GRADUAL COOLING TREND.
THINGS MAY EVENTUALLY BECOME MORE INTERESTING LATE WEEK INTO THE
WEEKEND THOUGH THIS WILL BE AT LEAST PARTIALLY CONTINGENT ON WHETHER
OR NOT A COLD FRONT MOVING THROUGH THE PLAINS CAN SETTLE INTO THE
SOUTH PLAINS. THE COLD FRONT WILL MAKE ITS FIRST RUN SOUTHWARD
BEHIND A POTENT SHORTWAVE TROUGH RIDING ACROSS THE NORTHERN TIER OF
THE NATION AND SOUTHERN CANADA WEDNESDAY AND THURSDAY. CURRENT NWP
HOLDS THE FRONT TO OUR NORTH ON FRIDAY...AS INCREASING AMOUNTS OF
TROPOSPHERIC MOISTURE /POTENTIALLY ENHANCED BY REMNANTS OF DOLLY
AND A TAP OFF A TROPICAL CYCLONE YET TO FORM IN THE EASTERN
PACIFIC/ ARE FUNNELED AROUND THE RIDGE INTO THE DESERT SOUTHWEST.
THE BEST RAIN CHANCES WILL LIKELY REMAIN FOCUSED TO NORTH AND WEST
FRIDAY INTO FRIDAY NIGHT...AND WE HAVE DECREASED POPS SOMEWHAT
OVER THIS PERIOD.
THE LATEST ITERATION OF THE GFS AND ECMWF NOW TEND TO KEEP THE UPPER
RIDGE CENTERED CLOSE ENOUGH THROUGH THE WEEKEND TO MAKE IT A LITTLE
MORE UNCERTAIN WHETHER WE WILL FULLY BE ABLE TO TAP THE SUB-TROPICAL
AND TROPICAL MOISTURE. EVEN SO...THE NWP SUGGESTS THE OUTFLOW
AIDED FRONT WILL SAG INTO THE SOUTH PLAINS SOMETIME OVER THE
WEEKEND /AS EARLY AS FRIDAY NIGHT WITH THE ECMWF OR NOT UNTIL
SATURDAY NIGHT IN THE GFS/. REGARDLESS...IF THE FRONT CAN MAKE IT
INTO THE CWA IT WILL BRING MORE SIGNIFICANT COOLING ALONG WITH
ENHANCED RAIN CHANCES. GIVEN THE UNKNOWNS...WE HAVE NOT MADE MANY
ADJUSTMENTS TO THE FORECAST OVER THE WEEKEND AND HAVE MAINTAINED
THE HIGHEST POPS SATURDAY NIGHT...WHEN CONFIDENCE IS HIGHEST OF
THE QUASI-STATIONARY FRONT RESIDING SOMEWHERE LOCALLY.
THE FRONT WILL THEN LIFT BACK NORTHWARD EARLY NEXT WEEK AS PRESSURES
FALL ACROSS THE HIGH PLAINS...DOWNSTREAM OF A WESTERN STORM SYSTEM.
THIS WILL RESULT IN WARMER AND DRIER WEATHER FOR WEST TEXAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 92 64 93 64 89 / 10 10 10 10 10
TULIA 95 67 94 66 90 / 20 10 10 10 0
PLAINVIEW 94 66 93 67 90 / 20 10 0 0 0
LEVELLAND 95 67 93 67 89 / 10 10 10 10 10
LUBBOCK 97 70 93 68 90 / 10 10 0 0 0
DENVER CITY 97 67 93 67 89 / 10 10 10 10 10
BROWNFIELD 97 68 93 68 90 / 10 10 0 0 10
CHILDRESS 98 72 97 73 96 / 10 10 0 0 0
SPUR 97 69 96 71 93 / 10 10 0 0 10
ASPERMONT 98 73 98 73 96 / 10 10 0 0 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1218 PM CDT TUE SEP 2 2014
.AVIATION...
/18Z TAFS/
Expect VFR conditions through the next 12 hours with
gusty south southwest winds during the afternoon and early
evening. the return of MVFR CIGS will be likely early tomorrow
morning at KJCT, KBBD, and KSOA terminals. Low CIGS will burn off
as we approach noon tomorrow.
&&
.PREV DISCUSSION... /ISSUED 627 AM CDT TUE SEP 2 2014/
AVIATION...
/12Z TAFS/
VFR conditions should prevail across most West Central Texas
terminals through the period. However, we are seeing the expected
MVFR stratus developing on low cloud imagery, although remaining
pretty patchy at this point. Suspect that it will expand a little
more through sunrise, and then quickly dissipate. Even at those
locations it does effect, it will be a move in and out quickly
type of feature. Otherwise, gusty south winds through daylight
hours with just a scattered afternoon cu field developing.
PREV DISCUSSION... /ISSUED 354 AM CDT TUE SEP 2 2014/
SHORT TERM...
(Today and Tonight)
Another mild night ongoing across West Central Texas, with south
winds remaining strong enough to keep temperatures from dropping
very much. Readings still right around 80 degrees at 3 AM (08Z).
Models do indicate that some patchy low cloudiness will develop by
sunrise and spread northward into the area, with low cloud satellite
imagery showing some of this starting to develop across portions of
Central Texas.
Another hot day in store for the area, with the upper level ridge of
high pressure in control. The 00Z NAM showed some convection across
West Central Texas this afternoon, but the GFS is dry. Both the TTU
WRF and the HRRR both show a similar pattern, scattered sea breeze
activity pushing well inland today, but dissipating at sunset across
Central Texas. Thus, will not insert PoPs into the forecast.
After readings above the 100 degree mark at San Angelo and
Abilene, models indicate a slight cooling at 850MB today as a
little cooler and more moist air mass from the Gulf of Mexico
slides into the area. Will keep afternoon highs below the 100
degree mark, but still a degree or two above guidance. Mild again
tonight as south winds keep temperatures from dropping very
quickly. Again, stayed just a little above guidance, as it has
been too cool for the last several days.
LONG TERM...
Surface temperatures fall 2 to 3 degrees F Wednesday as 850 MB
temperatures fall another 1 to 2 degrees Celsius. Tropical Storm
Dolly in the Bay of Campeche is expected to move into Mexico
early Wednesday, and may send weak disturbances/moisture
northward to affect the I-10 corridor Thursday and Friday. This
is indicated mainly by the EC model, as the GFS model is dry and
the NAM model nearly so. Will keep rain chances out of forecast
for this time period, given the uncertainty and limited agreement
in the models.
For Saturday night into Sunday, however, both the GFS and EC
modes are still indicating a weak cold front to bring a slight
chance of showers and thunderstorms. Forecast already has rain
chances in for this time period, and will maintain them.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 100 76 96 74 95 / 5 5 5 5 5
San Angelo 98 75 95 74 94 / 5 5 10 10 10
Junction 95 77 93 74 93 / 10 10 10 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/18
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
436 PM MDT TUE SEP 2 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 420 PM MDT TUE SEP 2 2014
MAIN FORECAST CONCERN OVER THE NEXT FEW DAYS WILL BE THE
CRITICAL FIRE WEATHER CONDITIONS ACROSS THE CWA. IT TOOK A LITTLE
WHILE FOR RH VALUES TO DROP TO CRITICAL LEVELS THIS
AFTERNOON...BUT WE ARE CURRENTLY SEEING A RH OF AROUND 15 PERCENT
IN THE FOOTHILLS OF THE LARAMIE RANGE (FIRE WEATHER ZONES 309 AND
301). RH VALUES ARE GENERALLY 15-20 PERCENT TO THE WEST OF THE
LARAMIE RANGE. WITH GUSTS TO 25-30 MPH THROUGH EARLY
EVENING...THIS CONTINUES TO LOOK LIKE A MARGINAL RED FLAG EVENT
AND WILL KEEP THE WARNINGS GOING. CLOUD COVER THIS AFTERNOON IS
QUITE LIMITED WITH ONLY ISOLATED CUMULUS. SFC MOISTURE IS BETTER
IN SOUTHERLY WINDS JUST TO THE EAST OF THE CWA (DEUEL AND GARDEN
COUNTIES) BUT IT WILL BE TOUGH TO ADVECT THIS MOISTURE WESTWARD.
THE HRRR MODEL ALONG WITH THE OTHER MODELS DO NOT SHOW ANY QPF
OVER THE PANHANDLE TONIGHT SO WILL KEEP SLIGHT CHANE POPS OUT OF
THE FCST.
WEDNESDAY CONTINUES TO LOOK LIKE A MORE CRITICAL FIRE WEATHER DAY
OVER THE REGION. A SHORTWAVE MOVING FROM WASHINGTON INTO MONTANA
WILL INDUCE PRESSURE FALLS OVER WESTERN SOUTH DAKOTA WHICH
STRENGTHENS THE PRESSURE GRADIENT OVER ESPECIALLY SOUTHEAST WY.
MOS GUIDANCE SHOWS WINDS ABOUT 5 KTS HIGHER THAN THIS AFTN ALONG
WITH AN ADDITIONAL 5 DEGREES OF WARMING. THE FIRE WEATHER WATCH
FOR TOMORROW AFTN INCLUDES TWO ZONES (310 AND 306) THAT ARE NOT
INCLUDED IN TODAYS RED FLAG WARNING. THIS LOOKS GOOD SINCE BOTH
THESE ZONES WERE CLOSE TO HITTING THE CRITERIA TODAY AND
CONDITIONS WILL BE DRIER AND MORE BREEZY TOMORROW. THE DEEP
SOUTHWESTERLY FLOW WILL RESULT IN A VERY WARM DAY WITH HIGHS
RISING INTO THE UPPER 80S TO MID 90S ACROSS THE PLAINS. THIS COULD
BE ONE OF THE WARMEST DAYS FOR THE REST OF THE YEAR SINCE A COLD
FRONTAL PASSAGE IS STILL PROGGED FOR THURS MORNING. TEMPS WILL
DROP CLOSE TO 20 DEGREES ON THURS. STILL NO GOOD CHANCE OF PRECIP
THROUGH AT LEAST THURS EVENING. COULD BE ISOLATED SHOWERS
DEVELOPING BY THURS NIGHT ALTHOUGH THE MODEL TREND HAS BEEN TO
SHIFT THE MORE WIDESPREAD RAIN WELL TO THE SOUTH OVER NORTHWEST KS.
.LONG TERM...(FRIDAY THROUGH MONDAY NIGHT)
ISSUED AT 420 PM MDT TUE SEP 2 2014
MODELS ARE IN FAIR AGREEMENT WITH THE MEDIUM RANGE PERIOD SHOWING A
PERSISTENT QUASI-ZONAL PATTERN OVER THE CENTRAL CONUS. TEMPERATURES
WILL START OFF BELOW AVERAGE ON FRIDAY IN THE POST FRONTAL
AIRMASS...WITH THE SFC HIGH SLIDING TO THE SOUTHEAST ACROSS THE
CENTRAL PLAINS. SFC WINDS ACROSS THE HIGH PLAINS WILL BE OUT OF THE
SOUTHEAST AS THE SFC HIGH SLIDES SOUTHEAST...WITH CONVECTION
DEVELOPING OVER THE MOUNTAINS IN THE LATE AFTERNOON IN THIS LLVL
UPSLOPE REGIME. SHOULD STAY FAIRLY CAPPED ACROSS THE PLAINS WITHIN
THE COOLER AIRMASS...BUT CANT RULE OUT SHOWERS/WEAK TSTORMS
MAINTAINING AS THEY MOVE OFF THE MOUNTAINS AS A 70 KT JET AND
SHORTWAVE ENERGY WILL BE MOVING OVERHEAD AT THIS TIME. SATURDAY
LOOKS VERY SIMILAR ALBEIT WITH WEAKER UPSLOPE FLOW AND SLIGHTLY
WARMER TEMPS/HIGH INSTABILITY. SUNDAY AND MONDAY COULD SEE A BIT
MORE SUBTROPICAL MOISTURE ADVECT UP FROM THE SOUTHWEST AS A TROUGH
DIGS ALONG THE WEST COAST AND MOVES ACROSS THE GREAT BASIN. THE
DEEPEST MOISTURE LOOKS TO REMAIN TO OUR SOUTH...BUT CAN SEE SOME OF
THIS MOISTURE MAKING IT UP TO SOUTHERN PORTIONS OF THE CWA SO WILL
MAINTAIN AT LEAST SLIGHT CHANCE POPS FOR MUCH OF THE CWA. TEMPS WILL
INCREASE BACK TO MORE NORMAL VALUES FOR THIS TIME OF YEAR BY MONDAY
AS THE UPPER TROUGH DEEPENS AND A WARM AIR ADVECTION PATTERN
DEVELOPS OVER THE ROCKIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 1149 AM MDT TUE SEP 2 2014
VFR CONDITIONS WILL PREVAIL AT ALL SITES THROUGH THE PERIOD. GUSTY
SOUTHWEST WINDS WILL BE COMMON TODAY...WITH 20 TO 30 KTS POSSIBLE
FOR WYOMING AND 15 TO 20 KTS AT THE NEBRASKA AIRPORTS. COULD SEE
AN ISOLATED SHOWER NEAR KSNY LATE THIS AFTERNOON AND EVENING...BUT
CONFIDENCE IS LOW THAT THIS WILL MATERIALIZE SO WILL LEAVE IT OUT
OF THE TAF FOR NOW. WINDS WILL EASE THIS EVENING FOR MOST
AREAS...WITH BREEZY CONDITIONS EXPECTED TO LINGER NEAR KCDR
THROUGH THE EARLY OVERNIGHT PERIOD. GUSTY WINDS WILL RETURN ON
WEDNESDAY.
&&
.FIRE WEATHER...
ISSUED AT 420 PM MDT TUE SEP 2 2014
RELATIVE HUMIDITY VALUES HAVE DROPPED TO AROUND 15 PERCENT THIS
AFTERNOON OVER LOWER ELEVATIONS OF SOUTHEAST WYOMING. IN
ADDITION...WEST AND SOUTHWEST WINDS HAVE BEEN GUSTING TO 20-30
MPH. A RED FLAG WARNING REMAINS IN EFFECT THROUGH EARLY THIS
EVENING OVER PORTIONS OF SOUTHEAST WYOMING. TEMPERATURES WILL WARM
ON WEDNESDAY AND WINDS WILL BE MORE BREEZY DURING THE AFTERNOON
DUE TO A STRENGTHENING PRESSURE GRADIENT. THUS...EXPECT CRITICAL
FIRE WEATHER CONDITIONS TO BE MORE WIDESPREAD OVER SOUTHEAST
WYOMING AND FIRE WEATHER WATCHES ARE IN EFFECT. AN ELEVATED FIRE
WEATHER THREAT IS PREDICTED OVER THE WESTERN NEBRASKA PANHANDLE
DUE TO HUMIDITY VALUES FALLING TO 15-20 PERCENT AND WIND GUSTS OF
20-25 MPH DURING THE AFTERNOON. A COLD FRONT ON THURSDAY MORNING
WILL PUSH ACROSS THE AREA WITH MUCH COOLER TEMPERATURES FOR
THURSDAY AND INTO THE WEEKEND.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR WYZ301-302-304-306-309-310.
RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR WYZ301-302-304-
309.
NE...NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...RJM
AVIATION...RJM
FIRE WEATHER...FINCH