Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/30/15
AREA FORECAST DISCUSSION
NWS TUCSON AZ
852 PM MST WED JUL 29 2015
.SYNOPSIS...AN ELEVATED CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
SOUTHEAST ARIZONA WILL CONTINUE THIS WEEK WITH SOME STORMS PRODUCING
LOCALLY HEAVY RAIN AND STRONG WINDS. RAIN CHANCES WILL CONTINUE OVER
THE WEEKEND...BUT COVERAGE WILL DECREASE WITH A WEAKER FLOW AS HIGH
PRESSURE INCREASES ALOFT.
&&
.DISCUSSION...FAIRLY WIDESPREAD SHOWERS AND THUNDERSTORMS DEVELOPED
THIS AFTERNOON AND CONTINUE THIS EVENING...MAINLY FOCUSED FROM THE
CENTRAL PORTIONS OF THE FORECAST AREA EASTWARD. LATEST KEMX RADAR
IMAGERY SHOWS THE BULK OF THE STORMS OVER COCHISE AND SOUTHERN
GRAHAM COUNTY WITH SOME LIGHTER SHOWERS AND A FEW EMBEDDED
THUNDERSTORMS ACROSS EASTERN PIMA COUNTY. THERE WERE SOME
ISOLATED AREAS OF 1 TO 2 INCHES OF RAIN WITH THE HIGHEST TOTAL WE
RECEIVED BEING JUST UNDER 2 INCHES IN SAN MANUEL. HEADING THROUGH
THE REST OF THE EVENING AND THE OVERNIGHT...EXPECT SCATTERED
SHOWERS AND THUNDERSTORMS TO PERSIST ESPECIALLY ACROSS THE EASTERN
ZONES AS NUMEROUS RESIDUAL OUTFLOWS PERSIST. THIS IS IN GOOD
AGREEMENT WITH LATEST HRRR AS WELL WHICH GRADUALLY TAPERS
OFF CONVECTION OVERNIGHT FOR EASTERN ZONES. MEANWHILE...FOR
LOCATIONS ACROSS CENTRAL AND WESTERN PIMA COUNTY AND ADJACENT PINAL
COUNTY WE HAVE REDUCED POPS JUST A BIT AS OUTFLOWS ARE MAKING THEIR
WAY WESTWARD WITHOUT INITIATING CONVECTION. OTHERWISE...NO
SIGNIFICANT CHANGES EXCEPT MADE SOME MINOR TWEAKS TO THE FORECAST
TO ADJUST FOR LATEST TEMPERATURE TRENDS.
&&
.AVIATION...VALID THRU 31/00Z.
SCT CLOUDS AT 6-10K FT AGL...SCT-BKN CLOUDS AT 10-14K FT AGL AND BKN
CLOUDS AOA 20K FT AGL THRU 30/06Z. SLOWLY DIMINISHING CLOUDS AFT
30/06Z...WITH FEW-SCT CLOUDS AT 10-14K FT AGL AND SCT-BKN CLOUDS AOA
20K FT AGL BY 30/10Z. AFT 30/17Z...SCT-BKN CLOUDS AT 6-10K FT AGL
AND BKN-OVC CLOUDS AT 10-14K FT AGL. ISOLD-SCT SHRA/TSRA THRU
30/06Z...WITH SCT-NUMEROUS SHRA/TSRA DEVELOPING AGAIN AFT 30/17Z.
MVFR CONDITIONS AND VRB WIND GUSTS TO 40 KTS POSSIBLE IN AND AROUND
THE STRONGER TSRA. OUTSIDE OF STORM INFLUENCES...SFC WINDS WILL
GENERALLY BE LESS THAN 12 KTS WITH A FEW HIGHER GUSTS IN THE
AFTERNOON/EARLY EVENING HOURS. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.
&&
.FIRE WEATHER...A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS MUCH OF
SOUTHEAST ARIZONA INTO FRIDAY...WITH DIMINISHING PRECIPITATION
CHANCES OVER THE UPCOMING WEEKEND...ESPECIALLY FROM TUCSON NORTH AND
WEST. STRONG OUTFLOW WINDS WILL BE POSSIBLE NEAR THUNDERSTORMS...
WITH WIND GUSTS BETWEEN 40 AND 45 MPH. OTHERWISE...20-FT WINDS WILL
GENERALLY BE TERRAIN DRIVEN AND LESS THAN 15 MPH...WITH SOME
AFTERNOON AND EARLY EVENING BREEZINESS DUE TO THE STRONG DAYTIME
HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...GL
AVIATION/FIRE WEATHER...ZELL
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS RENO NV
152 PM PDT TUE JUL 28 2015
.SYNOPSIS...
CLEAR SKIES AND LIGHT NORTHEAST WINDS WILL CONTINUE THROUGH
WEDNESDAY, KEEPING SMOKE FROM WEST SLOPE WILDFIRES AWAY FROM THE
REGION. HIGH PRESSURE BUILDING OVER THE DESERT SOUTHWEST LATE WEEK
WILL TRANSPORT MOISTURE UP INTO THE REGION STARTING THURSDAY, WITH
DAILY CHANCES FOR THUNDERSTORMS THROUGH THE UPCOMING WEEKEND.
ABOVE NORMAL TEMPERATURES ARE EXPECTED THURSDAY THROUGH THE
WEEKEND.
&&
.SHORT TERM...
NO SIGNIFICANT CHANGES TO THE ONGOING FORECAST THROUGH THURSDAY.
FAIRLY STRONG PRESSURE GRADIENT OVER THE REGION LED TO NE WINDS
LAST NIGHT IN THE TAHOE/SIERRA REGION TO 30 MPH. WE SAW THE SURGES
OF NE WIND ON TAHOE WITH THE UNR SEISMO CAMERA FROM SNOW VALLEY
PEAK. THIS GRADIENT WILL REMAIN THROUGH THIS EVENING BUT THEN
START TO RELAX TOMORROW, WHICH WILL LEAD TO WARMING TEMPERATURES
EACH DAY THROUGH THURSDAY. RH RECOVERIES WILL CONTINUE TO BE POOR
TONIGHT, ESPECIALLY ON THE MID-SLOPES AND EAST OF 395. BASED ON
LATEST HRRR GUIDANCE, NE FLOW WILL KEEP SMOKE OUT OF THE EASTERN
SIERRA. THOUGH THERE COULD BE SOME HAZE NEAR MAMMOTH FROM THE
WILLOW FIRE AS A BRIEF PERIOD OF WESTERLIES KICKS IN EARLY THIS
EVENING.
LIKELY TO SEE A SCATTERING OF CUMULUS OVER THE SIERRA WEDNESDAY
AFTERNOON, BUT GFS SOUNDINGS SHOWING A STRONG CAP SO THEY WILL
HAVE LIMITED VERTICAL DEVELOPMENT. FLOW ALOFT TURNS SOUTHERLY
THURSDAY AS UPPER RIDGE BUILDS OVER THE DESERT SOUTHWEST, SLOWLY
BRINGING IN MOISTURE ABOVE 500MB. COULD SEE A FEW ISOLATED HIGH-
BASED TSTMS THURSDAY AFTERNOON ALONG THE SIERRA CREST AND WHITE
MOUNTAINS OF MONO COUNTY, BUT INSTABILITY IS QUITE UNIMPRESSIVE SO
COVERAGE WILL BE MINIMAL. FROM WHAT STORMS DO FORM - FAIRLY DRY
SUB-CLOUD LAYER WILL PROMOTE STRONG OUTFLOWS 50+ MPH, ALONG WITH
RISK OF LIGHTNING FIRE STARTS. CS
.LONG TERM...FRIDAY THROUGH MONDAY...
NO SIGNIFICANT CHANGES WERE MADE TO THE ONGOING FORECAST THIS
AFTERNOON. GENERAL SYNOPTIC PATTERN IS SHIFTING TOWARDS HIGH
PRESSURE ACROSS THE FOUR CORNERS REGION, WHICH WILL RESULT IN A
RETURN OF THUNDERSTORMS FOR MUCH OF THE SIERRA AND WESTERN NEVADA
FOR THE WEEKEND AND INTO EARLY NEXT WEEK. THERE ARE STILL SLIGHT
DIFFERENCES BETWEEN THE OPERATIONAL FORECAST MODELS, BUT
FORECASTER CONFIDENCE IS MEDIUM FOR INCREASING THUNDERSTORMS
COVERAGE THROUGH EARLY NEXT WEEK.
MOIST SOUTHERLY FLOW COMBINED WITH SUFFICIENT INSTABILITY FROM
HEATING WILL ALLOW THUNDERSTORMS TO DEVELOP EACH
AFTERNOON/EVENING. IT DOES APPEAR THAT THERE MAY BE A COUPLE OF
SHORTWAVES EMBEDDED IN THE SOUTHERLY FLOW, WHICH DEPENDING ON THE
TIMING, COULD RESULT IN THUNDERSTORMS TO CONTINUE OVERNIGHT OR
BEGIN EARLIER IN THE DAY. FORECASTER CONFIDENCE IS LOW WITH
DETAILS ON TIMING AND EXACT LOCATION OF STORMS, BUT ANYONE WITH
OUTDOOR ACTIVITIES PLANNED FOR THE WEEKEND SHOULD MONITOR THE
WEATHER FORECAST. WEISHAHN
&&
.AVIATION...
AN EASTERLY GRADIENT WILL PERSIST TODAY WITH GUSTY WINDS OVER
SIERRA RIDGES DIMINISHING IN THE AFTERNOON. THIS FLOW WILL KEEP
MOST OF THE HAZE AND SMOKE ON THE WEST SIDE OF THE CREST AND AWAY
FROM EASTERN SIERRA TERMINALS. LIGHT EASTERLY FLOW WILL PERSIST
ACROSS THE SIERRA AND WESTERN NEVADA TOMORROW. HOHMANN/WEISHAHN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1029 PM EDT WED JUL 29 2015
.SYNOPSIS...
WEAK HIGH PRESSURE WILL SLIDE OFF THE MID ATLANTIC COAST TONIGHT.
A COLD FRONT WILL APPROACH ON THURSDAY...AND MOVE ACROSS THURSDAY
NIGHT. WEAK HIGH PRESSURE WILL RETURN FRIDAY THROUGH SATURDAY. A
WEAK LOW PRESSURE TROUGH WILL MOVE THROUGH SATURDAY NIGHT INTO
EARLY SUNDAY...FOLLOWED BY ANOTHER WEAK TROUGH SUNDAY NIGHT. A
COLD FRONT WILL APPROACH MONDAY NIGHT...AND REMAIN NEARBY THROUGH
MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
FORECAST REMAINS ON TRACK. UPDATED THE NEAR TERM GRIDS TO BETTER
REFLECT TRENDS IN LATEST OBSERVATIONS AND MODEL DATA.
WARM AND MUGGY TONIGHT WITH LOWS IN THE 70S FOR MUCH OF THE
AREA ALTHOUGH A FEW SPOTS IN THE NYC METRO MAY STRUGGLE TO FALL
BELOW 80 DEGREES.
CONVECTION IN PARTS OF THE MID ATLANTIC AND CENTRAL
APPALACHIANS ASSOCIATED WITH AN APPROACHING SHORTWAVE HAS
LARGELY DISSIPATED OVER THE LAST FEW HOURS. HAVE CAPPED POPS AT
SLIGHT CHANCE AFTER MIDNIGHT NORTH AND WEST OF NYC AS NOT
EXPECTING MUCH IN THE WAY OF ACTIVITY WITH THIS SHORTWAVE...BUT AN
ISO SHOWER OR STORM CANNOT BE RULED OUT BEFORE DAYBREAK. THE LAST
SEVERAL RUNS OF THE HRRR HINT AT THIS POSSIBILITY AS WELL AS THE
NEW 00Z NAM.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
COULD STILL SEE ISO TO WDLY SCT ELEVATED CONVECTION FROM NYC
METRO NORTH/WEST IN THE MORNING AS THE LEADING SHORTWAVE MOVES
THROUGH. APPROACHING COLD FRONT SHOULD BRING SCT TO NUMEROUS TSTMS
FROM LATE AFTERNOON INTO THE EVENING AS AIR MASS
DESTABILIZES...WITH SBCAPE UP TO 1000 J/KG. THERE SHOULD BE ENOUGH
SHEAR TO SUPPORT AN ORGANIZED LINE OF STORMS OR MULTI-CELL
CLUSTERS...AND GIVEN A SW LLJ UP TO 35 KT AS FCST PER NAM...THESE
STORMS HAVE A BETTER CHANCE OF SURVIVING AS THEY MOVE PAST NYC
METRO AND THE LOWER HUDSON VALLEY INTO LONG ISLAND AND CT.
STRONGER CELLS HAVE POTENTIAL TO PRODUCE STRONG WIND GUSTS AND
DUMP LOCALLY HEAVY RAINFALL AS PW INCREASES TO JUST OVER 2 INCHES.
HIGHS ON THURSDAY SHOULD BE NOT QUITE AS WARM AS TODAY...GENERALLY
85-90...BUT WITH HIGHER DEWPOINTS MAX HEAT INDEX VALUES SHOULD
STILL BE SIMILAR TO THOSE OF TODAY...STILL REACHING THE MID 90S
EXCEPT IN THE HIGHER ELEVATIONS AND EASTERN COASTAL SECTIONS...SO
THE HEAT ADVY WILL CONTINUE FOR NYC.
THERE IS A HIGH RISK OF RIP CURRENTS AT OCEAN BEACHES ON
THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LONG WAVE UPPER LEVEL TROUGH WILL BE OVER THE NORTHEAST U.S. FOR
MUCH OF THIS TIME PERIOD. AT THE SURFACE...A COLD FRONT WILL REMAIN
JUST OFF THE EAST COAST FRIDAY...WITH WEAK HIGH PRESSURE BUILDING
IN. SUBSIDENCE FROM THIS HIGH SHOULD KEEP THE AREA DRY THROUGH MUCH
OF SATURDAY. A WEAK SURFACE TROUGH APPROACHES LATE
SATURDAY...WEAKENING AS IT DOES SO. 12Z GFS DOES SEEM MORE POTENT AS
OPPOSED TO THE 00Z ECMWF AND BRINGS THE TROUGH THROUGH LATE SATURDAY
NIGHT WITH A BRIEF PERIOD OF SHOWERS AND THUNDERSTORMS. SOME
INSTABILITY PRECEDING THE TROUGH...SO THUNDERSTORMS ARE POSSIBLE.
HOWEVER...JET DYNAMICS LOOK WEAK...THOUGH LIFT WITH THE TROUGH AT
LEAST EARLY IN THE NIGHT LOOKS DECENT ACCORDING TO THE 12Z GFS.
HOWEVER...LIFT QUICKLY WEAKENS AS THE TROUGH MOVES EAST LATE
SATURDAY NIGHT.
WEAK HIGH PRESSURE BUILDS IN FOR SUNDAY AND MONDAY WITH A COLD FRONT
APPROACHING MONDAY NIGHT. COLD FRONT SLOWS ITS APPROACH AND BECOMES
NEARLY STATIONARY IN THE VICINITY MONDAY NIGHT INTO WEDNESDAY.
AGAIN...SOME INSTABILITY OVER THE AREA AS THE FRONT MOVES
THROUGH...MAINLY FOR EASTERN SECTIONS...SO THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE. LIFTED INDICES -8 TO -2 DURING TUESDAY NIGHT...WITH
LIFT BEING PROVIDED BY THE FRONT. MOISTURE IS ALSO AVAILABLE...WITH
SURFACE DEWPOINTS IN THE 60S AND PW RANGING FROM 1.25-1.50...THOUGH
THEY ARE NOT EXCEPTIONALLY HIGH.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
A SOUTHERLY FLOW CONTINUES AROUND HIGH PRESSURE OFF THE MID
ATLANTIC COAST AS A COLD FRONT THROUGH THE GREAT LAKES AND INTO
OHIO SLOWLY APPROACHES. THE COLD FRONT AND A WEAK PRE FRONTAL TROUGH
WILL BE MOVING INTO THE TERMINALS AROUND 18Z THURSDAY AND MOVE
THROUGH THURSDAY EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL
ACCOMPANY THE FRONT WITH MVFR CONDITIONS...OR POSSIBLY IFR IN
STRONGER STORMS. THERE IS A HIGHER CHANCE OF CONVECTION FROM THE NYC
TERMINALS AND AREAS WEST. WILL CONTINUE TO INDICATE THE CHANCES WITH
A PROB GROUP.
OTHERWISE VFR UNTIL TOWARD MORNING WHEN MVFR VISIBILITIES WILL BE
POSSIBLE IN FOG AND/OR HAZE.
.OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
.THURSDAY NIGHT...SCATTERED SHOWERS AND THUNDERSTORMS ENDING IN THE
EVENING WITH MVFR CONDITIONS POSSIBLE...THEN BECOMING VFR.
.FRIDAY-MONDAY...VFR.
&&
.MARINE...
QUIET THROUGH THU MORNING. THEN AS SW FLOW INCREASES TO 15-20 KT
WITH FAVORABLE FETCH...OCEAN SEAS SHOULD BUILD TO 5-6 FT THU
AFTERNOON AND NIGHT. LOW LEVEL JET PASSING OHD SHOULD MIX TO THE
SFC...WITH GUSTS UP TO 25 KT LIKELY ON THE OCEAN AND THE BAYS OF
LONG ISLAND. SCA ISSUED FOR THESE HAZARDS. TSTMS WILL ALSO BE A
HAZARD WITH A COLD FRONTAL PASSAGE THU AFTERNOON/EVENING.
OCEAN SEAS COULD BUILD TO AROUND 5 FT SAT NIGHT INTO SUNDAY...
AND AGAIN LATE SUNDAY INTO MONDAY MORNING. THEN A MORE PROLONGED
PERIOD OF 5-FT OCEAN SEAS IS POSSIBLE FROM MON NIGHT INTO MID
WEEK.
&&
.HYDROLOGY...
BASIN AVG QPF OF 1/2 TO 3/4 INCH POSSIBLE IN THE LOWER HUDSON
VALLEY AND NE NJ...WITH UP TO 1/2 INCH ELSEWHERE. WITH PW OVER 2
INCHES THU AFTERNOON AND EVENING...LOCALLY HEAVY RAINFALL IS
POSSIBLE WITH ANY STRONGER CONVECTION. MINOR URBAN/POOR DRAINAGE
FLOODING IS THE MOST LIKELY OUTCOME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...HEAT ADVISORY UNTIL 8 PM EDT THURSDAY FOR NYZ072>075-176-178.
HIGH RIP CURRENT RISK FROM 6 AM EDT THURSDAY THROUGH THURSDAY
EVENING FOR NYZ075-080-081-178-179.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM TO 8 PM EDT THURSDAY FOR ANZ340-
345.
SMALL CRAFT ADVISORY FROM NOON THURSDAY TO MIDNIGHT EDT
THURSDAY NIGHT FOR ANZ355.
SMALL CRAFT ADVISORY FROM NOON THURSDAY TO 6 AM EDT FRIDAY FOR
ANZ350-353.
&&
$$
SYNOPSIS...GOODMAN/JP
NEAR TERM...GOODMAN/DS
SHORT TERM...GOODMAN/DS
LONG TERM...JP
AVIATION...MET
MARINE...GOODMAN/JP
HYDROLOGY...GOODMAN/JP
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
957 PM EDT WED JUL 29 2015
.UPDATE...BROAD SURFACE LOW PRESSURE WAS DRIFTING SOUTHWARD OVER
GA WITH A TROUGH AXIS MEANDERING OVER THE LOCAL FORECAST AREA
TOWARD A DEEPER SURFACE LOW OFFSHORE OF THE FL/GA ATLANTIC
WATERS. AN UPPER LEVEL RIDGE CONTINUED TO DOMINATE OVER THE MS
RIVER VALLEY WITH WEAK UPPER LEVEL IMPULSES TREKKING SSW ON THE
EASTERN PERIPHERY OF THE RIDGE ACROSS GA. DRIER AND MUCH MORE
STABLE AIR DOMINATED ACROSS OUR COASTAL ZONES AND ALONG THE ST
JOHNS RIVER BASIN TODAY ON THE WEST SIDE OF THE SURFACE LOW
OFFSHORE WHICH KEPT CONVECTION MINIMAL ACROSS THE EASTERN HALF OF
THE CWA TODAY...WHILE UPPER LEVEL FORCING AND SHALLOW BOUNDARIES
ACROSS OUR INLAND ZONES CONTINUED TO FUEL SLOW MOVING BACKBUILDING
CELLS ACROSS SE GA.
THE HRRR GUIDANCE INITIALIZED WELL WITH CONVECTION TODAY AND WAS
USED IN THE EVENING UPDATE. ADVERTISED PRECIP FADING ACROSS NE FL
THROUGH MIDNIGHT WHILE CONTINUED SCATTERED NOCTURNAL ACTIVITY
ACROSS OUR WESTERN GA ZONES THROUGH EARLY THU MORNING WITH A DRIFT
IN PRECIP TOWARD THE SSW TOWARD APALACHEE THROUGH THU MORNING.
EARLY THU MORNING PRECIP IS EXPECTED TO FADE OVER INLAND SE GA
AND FOCUS ACROSS APALACHEE BAY...THEN BEGIN TO EDGE INLAND UNDER
LOW LEVEL WSW FLOW.
MIN TEMPS WILL BE MILD WITH VALUES IN THE LOW/MID 70S INLAND TO
UPPER 70S ALONG THE ST JOHNS RIVER BASIN AND ATLANTIC COAST.
ADVERTISED PATCHY FOG IN THE GRIDS MAINLY ACROSS OUR EASTERN ZONES
WHERE SKIES WILL CLEAR MOST OVERNIGHT.
&&
.AVIATION...
VFR WILL GENERALLY PREVAIL. SOME PATCHY FOG WILL BE POSSIBLE LATE
TONIGHT BUT CHANCES ARE TOO LOW TO WARRANT INCLUSION IN THE TAFS.
SCATTERED TO NUMEROUS CONVECTION WILL BUILD TOWARDS THE EAST COAST
ON THURSDAY AND WE WILL COVER THIS WITH PROB30 AND VCTS GROUPS FOR
NOW.
&&
.MARINE...LIGHT SSW FLOW WILL DEVELOP OVERNIGHT WITH A BROAD
TROUGH AXIS LINGERING OVER THE WATERS. COMBINED SEAS WILL
GENERALLY BE 3 FT OR LESS.
RIP CURRENTS: LOW RISK THURSDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 74 94 75 93 / 30 50 30 50
SSI 76 88 78 88 / 10 30 30 40
JAX 75 92 75 90 / 20 50 30 60
SGJ 75 89 76 89 / 10 50 30 60
GNV 74 89 74 89 / 40 60 30 70
OCF 74 89 74 89 / 50 60 40 70
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
ENYEDI/SHULER/GUILLET
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
201 PM EDT TUE JUL 28 2015
.DISCUSSION...
CURRENT/REST OF TUE AFTERNOON...SHOWERS AND A STORM OR TWO WILL MOVE
NORTHEAST AT 20 MPH FROM THE FLORIDA SOUTHWEST AND WEST CENTRAL
COASTS ACROSS CENTRAL AND EAST CENTRAL FLORIDA AND INTO THE
NEARSHORE WATERS.
LATEST RUC 500MB PLOT SHOWING THE UPPER TROUGH WAS STILL JUST WEST
OF CENTRAL FLORIDA AND VERIFIED WITH USAF VERTICAL WIND PROFILERS
AT/VICINITY OF KENNEDY SPACE CENTER DETECTING SOUTHWEST WIND 20 TO
30 KNOTS THROUGH 6000 FEET. TEMPERATURES AT 500MB PER BOTH TAMPA AND
CAPE CANAVERAL 27/12Z SOUNDINGS WERE AROUND -5C. AS LONG AS CENTRAL
FLORIDA IS IN THE DEEP AND BRISK SOUTHWEST FLOW... DEEP MOISTURE AND
TEMPERATURES ALOFT WILL REMAIN WARM. THIS IS MORE CONDUCIVE FOR FAST
MOVING HEAVY SHOWERS ANY TIME. EXCEPTIONS WOULD BE MARTIN AND MOST
OF SAINT LUCIE COUNTIES WHICH ARE DOWNWIND OF LAKE OKEECHOBEE AND IN
THE LAKE SHADOW EFFECT.
TUE OVERNIGHT-THU NIGHT...NO SIGNIFICANT CHANGE TO THE ONGOING
SYNOPTIC SCALE PICTURE WITH UPPER LEVEL HIGHS TO THE WEST AND TO THE
EAST OF THE FLORIDA PENINSULA AND A TROUGH OF LOWER PRESSURE BETWEEN
THE TWO LEVEL HIGH CENTERS. QUASI STATIONARY FRONT STRETCHING FROM
AN AREA OF LOW PRESSURE IN THE NORTHEAST GULF OF MEXICO/FLORIDA BIG
BEND AREAS SLIDES UP/DOWN CENTRAL FLORIDA AS SHORT WAVES RIDING
OVERTOP OF THE MID NATION RIDGE DROP SOUTHEAST ACROSS THE SOUTHEAST
U.S. AND FLORIDA. EXACT TIMING OF WHEN THESE SHORT WAVES WILL MOVE
THE FRONT UP/DOWN HARD TO FORECAST MUCH BEYOND 12-24 HOURS. DEEP
LAYER MOISTURE/PRECIPITABLE WATER VALUES FORECAST TO REMAIN BETWEEN
2.09 AND 2.5 INCHES THROUGH THU NIGHT...AND BEYOND. GFS MAV MOS
LOOKS TO HAVE MADE A DOWNWARD ADJUSTMENT OF AROUND 20 PERCENT FROM A
50 TO A 30 POP FROM 24 HOURS AGO. STILL SCATTERED/CHANCE POP THOUGH.
THE 28/12Z GFS ATTEMPTS TO PUSH THE STATIONARY FRONT INTO CENTRAL
FLORIDA BUT FOR NOW WILL TAKE A WAIT AND SEE ATTITUDE IF THAT REALLY
HAPPENS.
FRI...THE AREA WILL CONTINUE TO RESIDE WITHIN A WEAKNESS IN THE
SUBTROPICAL RIDGE ALOFT. THERE IS NO APPARENT SUPPRESSING FORCE TO
SIGNIFICANTLY DRY OUT THE VERY MOIST AIR MASS...THOUGH THE 00Z GFS
DID SHOW MINOR DRYING IN THE NORTH WED AND IN THE SOUTH THU. THESE
SUBTLE DAY TO DAY CHANGES ARE DIFFICULT TO PRECISELY FORECAST...BUT
DID BLEND THEM INTO THE FORECAST POPS WHICH ARE CLOSE TO CONSENSUS
VALUES.
WITH WEST/SOUTHWEST FLOW PATTERN CONTINUING WE WILL HAVE AT LEAST
SCATTERED POPS EACH DAY. CAME OUT WITH LIKELY POPS IN THE NORTH HALF
ON THU AND ACROSS THE AREA FRI. THE DAILY CHANGES IN RAIN CHANCES
AND CLOUDINESS WILL DICTATE MAX TEMPS BUT DID LEAN TOWARDS SLIGHTLY
LOWER CONSENSUS VALUES.
WEEKEND-NEXT TUE...THE FLOW PATTERN ALOFT AT THESE LATITUDES WILL
LIKELY BE IN A NEAR STAND OFF AS WESTERN CONUS RIDGE IS FORECAST TO
HOLD SWAY WHILE TROUGHING OVER THE EAST KEEPS ATLANTIC RIDGE FROM
BUILDING ACROSS THE FLORIDA PENINSULA IN EARNEST. WEAKNESS IN THE
RIDGE SHOULD REMAIN NEARBY AND ONLY LIMITED DEEP LAYER DRYING IS
INDICATED. SURFACE RIDGE AXIS IS FORECAST TO NUDGE TOWARDS CENTRAL
FLORIDA BUT STEERING FLOW FROM THE SOUTH/SOUTHWEST SHOULD KEEP
SCATTERED POPS OVER THE EASTERN SIDE OF THE PENINSULA.
.AVIATION...WENT WITH PREDOMINATELY MVFR CEILINGS THROUGH 29/00Z.
TIME OF IFR CEILINGS TOO SHORT TO GO WITH TEMPO GROUP. KDAB WAS
THE ONLY TAF SITE THAT REPORT TS MONDAY AFTERNOON. WITH FAST
MOVING SHOWERS A VCTS MAY BE A BETTER CALL THAN A TEMPO GROUP. VFR
AFTER MIDNIGHT. VCSH LATE OVERNIGHT AS SHOWERS ASSOCIATED WITH THE
LOW OVER THE GULF MOVE NORTHEAST.
.MARINE...
CURRENT-TONIGHT...NOAA BUOYS RECORDING SOUTH TO SOUTHWEST WINDS 15
TO 20 KNOTS AND 2 TO 4 FOOT SEAS. THE SCRIPPS BUOYS RECORDING 1 TO 2
FOOT SEAS. WILL KEEP THE SMALL CRAFT EXERCISE CAUTION FOR WINDS ON
THE OFFSHORE WATERS.
PREVIOUS AFD
WED-THU...WEAK LOW PRESSURE SHOULD SHIFT TO NORTH FLORIDA AND SOUTH
GEORGIA AND EASE THE SOUTHWESTERLY WIND FLOW...THOUGH THE 00Z GFS
DOES NOT DO THIS UNTIL THU. A CHANCE FOR QUICK MOVING OFFSHORE
SQUALLS/STORMS SHOULD CONTINUE...ESPECIALLY ON WED SOUTH OF
CANAVERAL.
FRI-SAT...THE ATLANTIC HIGH PRESSURE RIDGE AXIS IS STILL FORECAST TO
BUILD TOWARDS SOUTH FLORIDA ON SAT. PRESSURE GRADIENT SHOULD SUPPORT
10-15 KNOT SOUTHWEST FLOW. IT LOOKS QUITE MOIST BOTH DAYS AND THE
LATEST GFS RUN INDICATES A LITTLE STRONGER STEERING FLOW OUT OF THE
SOUTHWEST ON SAT...SO BOATERS MUST REMAIN MINDFUL OF THE THREAT THAT
OFFSHORE MOVING STORMS POSE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 74 91 74 92 / 40 30 20 30
MCO 76 92 75 92 / 40 30 20 30
MLB 76 91 74 91 / 40 40 20 30
VRB 75 91 73 91 / 20 40 20 30
LEE 76 93 77 92 / 30 30 20 30
SFB 76 92 76 92 / 40 30 20 30
ORL 77 92 77 92 / 40 30 20 30
FPR 75 91 73 92 / 20 30 20 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
IMPACT WX...PENDERGRAST
FORECASTS...WIMMER
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
925 AM EDT TUE JUL 28 2015
.DISCUSSION...
CURRENT-UPDATES...BUOY OBS SHOW AN AREA OF LOW PRESSURE IN THE
NORTHEAST GULF/FLORIDA BIG BEND AREAS. TROUGHING EXTENDS TO THE
SOUTHWEST INTO THE GULF OF MEXICO AND NORTHEAST ACROSS NORTH FLORIDA
INTO THE WESTERN ATLANTIC. LATEST RUC 500MB PLOT SHOWING THE UPPER
TROUGH WAS STILL JUST WEST OF CENTRAL FLORIDA AND VERIFIED WITH USAF
VERTICAL WIND PROFILERS AT/VICINITY OF KENNEDY SPACE CENTER
DETECTING SOUTHWEST WIND THROUGH 10000 FEET. LOCAL WRF AND HRRR
COVERAGE NOT AS MUCH AS IN PREVIOUS DAYS BUT STILL SHOWING MORE
PRECIP OVER NORTHERN AREAS. TEMPERATURES AT 500MB PER BOTH TAMPA AND
CAPE CANAVERAL 27/12Z SOUNDINGS WERE AROUND -5C. AS LONG AS CENTRAL
FLORIDA IS IN THE DEEP SOUTHWEST FLOW... TEMPERATURES ALOFT SHOULD
REMAIN WARM. THIS WOULD CONDUCIVE FOR FAST MOVING HEAVY SHOWERS ANY
TIME.
THIS IS WHAT THE LOCAL FORECAST IS INDICATING. WILL UPDATE WINDS AND
ASSOCIATED GRIDS.
.AVIATION...AFTER WATCHING RADAR LOOPS WENT EARLIER WITH VCSH. TEMPO
MVFR CEILINGS THROUGH NOON PREVAILING THROUGH 29/00Z. KDAB WAS THE
ONLY TAF SITE THAT REPORT TS MONDAY AFTERNOON. WITH FAST MOVING
SHOWERS AND STORMS A VCTS MAY BE A BETTER CALL THAN A TEMPO GROUP.
.MARINE...NOAA BUOYS RECORDING SOUTH TO SOUTHWEST WINDS 15 TO 20
KNOTS AND 2 TO 4 FOOT SEAS. THE SCRIPPS BUOYS RECORDING 1 TO 2 FOOT
SEAS. WILL KEEP THE SMALL CRAFT EXERCISE CAUTION FOR WINDS ON THE
OFFSHORE WATERS.
PREVIOUS AFD
TODAY-TONIGHT...PERSISTENT QUASI-STATIONARY LOW LEVEL BOUNDARY
REMAINS ACROSS THE FLORIDA PENINSULA EARLY THIS MORNING. A WEAK
AREA OF LOW PRESSURE IN THE EASTERN GULF NEAR CEDAR KEY HAS PULLED
IT FAIRLY FAR NORTHWARDS INTO NORTH FLORIDA. WITH THE BOUNDARY
FARTHER NORTH AND THE UPPER LEVEL TROUGH CONTINUING TO STRING OUT
IN THE SAME AREA...THE WESTERN ATLANTIC RIDGE AXIS HAS BEEN ABLE
TO LIFT A LITTLE FURTHER NORTH INTO THE FL STRAITS/FAR S FLORIDA.
THIS HAS ALLOWED A LITTLE MORE DRY AIR INTO S FLORIDA AS EVIDENCED
BY LAST EVENING`S SOUNDINGS WITH PWATS AT MIAMI "ONLY" AROUND 1.8"
WHILE THE REMAINDER OF PENINSULAR FL REMAINS IN THE 2.2" RANGE.
THE SQUEEZE BETWEEN THE TWO FEATURES WILL ALSO KEEP FAIRLY BRISK
SOUTH-SOUTHWEST STEERING FLOW AT 20-25KTS.
MODELS SHOW A SPREAD IN RAIN CHANCES FROM TODAY WITH NEARLY 90% FROM
THE ORLANDO METRO NORTHWARDS AND ONLY AROUND 20% NEAR MARTIN COUNTY.
EVEN WITH A LITTLE DRYING...DONT THINK SPREAD WILL BE QUITE THAT
DRASTIC GIVEN THE OTHERWISE FAVORABLE SW FLOW. WILL KEEP 60-70% FROM
OSCEOLA-BREVARD NORTHWARDS ENHANCED BY THE BOUNDARY TAPERING OFF TO
30-40% NEAR LAKE OKEECHOBEE AND SOUTHERN MARTIN.
EXPECT A SIMILAR EVOLUTION AS YESTERDAY...WITH ONGOING SHOWERS AND
STORMS OVER THE EASTERN GULF AND W FL COAST SPREADING INLAND MID TO
LATE MORNING AND ACTIVITY GENERALLY PUSHING OFFSHORE TOWARDS LATE
AFTERNOON. CONTINUING WARM TEMPERATURES ALOFT AND WEAK LAPSE RATES
WILL LEAN MORE TOWARDS RAIN WITH A FEW EMBEDDED STORMS...WITH QUICK
STORM MOTION ABLE TO PRODUCE A FEW GUSTS TO 40-50 MPH.
WED-FRI...THE AREA WILL CONTINUE TO RESIDE WITHIN A WEAKNESS IN
THE SUBTROPICAL RIDGE ALOFT. THERE IS NO APPARENT SUPPRESSING
FORCE TO SIGNIFICANTLY DRY OUT THE VERY MOIST AIR MASS...THOUGH
THE 00Z GFS DID SHOW MINOR DRYING IN THE NORTH WED AND IN THE
SOUTH THU. THESE SUBTLE DAY TO DAY CHANGES ARE DIFFICULT TO
PRECISELY FORECAST...BUT DID BLEND THEM INTO THE FORECAST POPS
WHICH ARE CLOSE TO CONSENSUS VALUES.
WITH WEST/SOUTHWEST FLOW PATTERN CONTINUING WE WILL HAVE AT LEAST
SCATTERED POPS EACH DAY. CAME OUT WITH LIKELY POPS IN THE NORTH
HALF ON THU AND ACROSS THE AREA FRI. THE DAILY CHANGES IN RAIN
CHANCES AND CLOUDINESS WILL DICTATE MAX TEMPS BUT DID LEAN TOWARDS
SLIGHTLY LOWER CONSENSUS VALUES.
WEEKEND-NEXT TUE...THE FLOW PATTERN ALOFT AT THESE LATITUDES WILL
LIKELY BE IN A NEAR STAND OFF AS WESTERN CONUS RIDGE IS FORECAST
TO HOLD SWAY WHILE TROUGHING OVER THE EAST KEEPS ATLANTIC RIDGE
FROM BUILDING ACROSS THE FLORIDA PENINSULA IN EARNEST. WEAKNESS IN
THE RIDGE SHOULD REMAIN NEARBY AND ONLY LIMITED DEEP LAYER DRYING
IS INDICATED. SURFACE RIDGE AXIS IS FORECAST TO NUDGE TOWARDS
CENTRAL FLORIDA BUT STEERING FLOW FROM THE SOUTH/SOUTHWEST SHOULD
KEEP SCATTERED POPS OVER THE EASTERN SIDE OF THE PENINSULA.
&&
.AVIATION...MVFR/IFR CIGS NOT AS PREVALENT THIS MORNING AS THE PAST
FEW DAYS...BUT WITH SEVERAL SITES STILL REPORTING FEW-SCT020-
025...WILL KEEP THE MENTION FOR TEMPO CIGS THROUGH DAYBREAK. KLEE
CLOSER TO THE BOUNDARY HAS BEEN SEEING MORE PREVAILING IFR CIGS SO
WILL KEEP PREVAILING IN THIS AREA THROUGH DAYBREAK.
OTHERWISE ONGOING SHOWERS/STORMS MOVING INTO KTPA-KZPH AND VCNTY
WILL SPREAD EASTWARDS AFTER 11Z FIRST AFFECTING KISM. SCT-NMRS SHRA
AND A FEW TSRA PUSHING EASTWARDS NORTH OF KLAL-KMLB 13Z-22Z WITH
COVERAGE ALONG OKEECHOBEE AND TREASURE COAST A LITTLE LOWER. GUSTS
TO 35KTS MAY AFFECT A FEW SITES AS ACTIVITY PUSHES THROUGH.
&&
.MARINE...
TODAY-TONIGHT...LOW LEVEL BOUNDARY HAS LIFTED INTO N FLORIDA THIS
MORNING WITH S-SW FLOW 10-15KTS PRESENT OVER ALL THE LOCAL ATLANTIC.
LITTLE CHANGE IN THE OVERALL WIND FIELD INTO TONIGHT. SEAS 2-3FT
WITH 4FT WELL OFFSHORE IN CONTINUING SHORT PERIODS 3-5SEC DUE TO
OFFSHORE FLOW. ANOTHER ROUND OF GUSTY SHOWERS AND STORMS EXPECTED TO
MOVE OFF THE COAST FROM LATE MORNING ONWARDS.
WED-THU...WEAK LOW PRESSURE SHOULD SHIFT TO NORTH FLORIDA AND
SOUTH GEORGIA AND EASE THE SOUTHWESTERLY WIND FLOW...THOUGH THE
00Z GFS DOES NOT DO THIS UNTIL THU. A CHANCE FOR QUICK MOVING
OFFSHORE SQUALLS/STORMS SHOULD CONTINUE...ESPECIALLY ON WED SOUTH
OF CANAVERAL.
FRI-SAT...THE ATLANTIC HIGH PRESSURE RIDGE AXIS IS STILL FORECAST
TO BUILD TOWARDS SOUTH FLORIDA ON SAT. PRESSURE GRADIENT SHOULD
SUPPORT 10-15 KNOT SOUTHWEST FLOW. IT LOOKS QUITE MOIST BOTH DAYS
AND THE LATEST GFS RUN INDICATES A LITTLE STRONGER STEERING FLOW
OUT OF THE SOUTHWEST ON SAT...SO BOATERS MUST REMAIN MINDFUL OF
THE THREAT THAT OFFSHORE MOVING STORMS POSE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 88 74 92 76 / 70 30 40 20
MCO 89 75 91 76 / 70 30 50 20
MLB 92 75 89 75 / 60 20 50 20
VRB 92 75 90 73 / 50 20 50 20
LEE 89 76 93 77 / 70 30 50 20
SFB 90 75 94 77 / 70 30 50 20
ORL 89 76 93 77 / 70 30 50 20
FPR 93 75 90 74 / 50 20 50 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
IMPACT WX...PENDERGRAST
FORECASTS...WIMMER
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
648 PM EDT TUE JUL 28 2015
.SYNOPSIS...
SUFFICIENT ATMOSPHERIC MOISTURE ALONG WITH A WEAK SURFACE TROUGH
IS EXPECTED TO BRING A CHANCE OF MAINLY AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS THROUGH THURSDAY. RAIN CHANCES ARE
EXPECTED TO INCREASE FRIDAY INTO THE WEEKEND AS A FRONT AND
ENHANCED ATMOSPHERIC MOISTURE AFFECT OUR REGION.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AN AXIS OF CONVERGENCE RUNNING FROM THE CSRA INTO THE CATAWBA
REGION HAS ALLOWED SHOWERS TO DEVELOP AROUND 17Z. MODERATE
INSTABILITY AND UPPER LEVEL DISTURBANCES WILL SUPPORT FURTHER
CONVECTIVE DEVELOPMENT THIS AFTERNOON. MOISTURE APPEARS TO BE
INCREASING ACROSS THE AREA WITH PRECIPITABLE WATER AROUND 2
INCHES. STORM MOTION WILL BE WEAK WITH LITTLE WIND IN THE CLOUD
LAYER. SLOW MOVING CONVECTION WITH HIGH PWAT VALUES MAY RAISE A
FLOODING CONCERN THIS AFTERNOON.
CONVECTION SHOULD DIMINISH THIS EVENING AS DIURNAL HEATING CUTS OFF.
LIGHT WINDS AND HIGH LOW LEVEL MOISTURE MAY ALLOW FOR STRATUS TO
DEVELOP OVERNIGHT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
UPPER HIGH WILL REMAIN CENTERED TO OUR WEST WITH UPPER TROUGH
ALONG THE EAST COAST. WEAKENING UPPER LOW AND STALLED FRONT TO
REMAIN TO OUR SOUTH. AN UPPER IMPULSE OR TWO ALONG WITH A WEAK
SURFACE TROUGH...SEA BREEZE...OR OTHER BOUNDARIES AND SUFFICIENT
ATMOSPHERIC MOISTURE IS EXPECTED TO LEAD TO A CHANCE OF MAINLY
DIURNAL CONVECTION.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
MODELS CONTINUE TO INDICATE UPPER HIGH CENTER TO SHIFT WEST TO
THE FOUR CORNERS REGION...WITH DEEPENING UPPER TROUGH OVER THE E
CONUS...ALLOWING A FRONT TO SLOWLY SHIFT SE INTO OUR REGION
FRIDAY. SOME SUBTLE DIFFERENCES BETWEEN GFS AND ECMWF. GFS APPEARS
TO MOVE FRONT THROUGH FRI NT OR EARLY SATURDAY STALLING IT TO OUR
SOUTH SAT INTO MON...WHILE ECWMF APPEARS TO STALL THE FRONT A
LITTLE FARTHER NORTH OVER OUR FA. ENHANCED MOISTURE ASSOCIATED
WITH THE STALLED FRONT TO OUR SOUTH MAY BE ABLE TO GET ENTRAINED
INTO THE SYSTEM. THIS AREA WILL ALSO HAVE TO BE MONITORED FOR
POSSIBLE LOW DEVELOPMENT WITH POSSIBLE IMPACTS ON OUR REGION.
CONTINUED TO ACCEPT A BLEND OF GUIDANCE AND ONGOING
FORECAST...LEADING TO INCREASED POPS FRIDAY WITH THE FRONT...AND
INDICATING A LITTLE HIGHER POPS TO THE SOUTH SAT INTO SUN.
UNCERTAINTIES LATE IN THE FORECAST PERIOD FOR EARLY NEXT WEEK.
SOME QUESTIONS REGARDING POSITION AND STATUS OF FRONT AND ANY
SURFACE WAVES/UPPER VORTS. MODELS SUGGEST MEAN UPPER TROUGH TO
REMAIN OVERHEAD ALONG WITH INDICATIONS OF SUFFICIENT MOISTURE.
SO...CHANCE POPS APPEAR OK FOR THAT TIME FRAME.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
RESTRICTIONS POSSIBLE EARLY WEDNESDAY MORNING AT ALL TAF SITES AND
IN AREAS OF CONVECTIVE SHOWERS EARLY THIS EVENING.
SCATTERED CONVECTION CONTINUES OVER PORTIONS OF THE MIDLANDS AND
CSRA EARLY THIS EVENING. HRRR INDICATING CONVECTION WILL END LATER
THIS EVENING.
INCREASING LOW LEVEL MOISTURE ACROSS THE FA MAY PRODUCE MVFR/IFR
CONDITIONS AT ALL TAF SITES EARLY WEDNESDAY MORNING. LIGHT WINDS
FAVOR LOW STRATUS IN THE MIDLANDS AND THE EASTERN FA. THE MODELS
ARE MOST PESSIMISTIC AT OGB BRINGING IN RESTRICTIONS AROUND 09Z.
EXTENDED AVIATION OUTLOOK...INCREASING CHANCES OF RESTRICTIONS
WEDNESDAY THROUGH SATURDAY IN MAINLY SCATTERED AFTERNOON AND
EVENING THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
319 AM EDT TUE JUL 28 2015
.SYNOPSIS...
THE REGION WILL REMAIN SITUATED BETWEEN WEAK HIGH PRESSURE TO THE
NORTH AND LOW PRESSURE TO THE SOUTH UNTIL LATE THIS WEEK.
THEN...BROAD LOW PRESSURE WILL DEVELOP AND WILL PERSIST OVER THE
REGION LATE THIS WEEK INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
THROUGH SUNRISE...CONDITIONS APPEAR SIMILAR TO YESTERDAY MORNING
WHERE WIDESPREAD DENSE FOG AFFECTED MUCH OF SOUTHEAST SOUTH
CAROLINA. SATELLITE DATA SHOW HIGH CLOUDS POISED TO CLEAR
SOUTHEAST GEORGIA VERY SOON...WHILE DEBRIS CLOUDINESS ASSOCIATED
WITH ONGOING CONVECTION OVER THE SOUTHERN FOOTHILLS OF NORTH
CAROLINA IS BEGINNING TO PROPAGATE INTO THE CHARLESTON TRI-COUNTY
AREA. THE LATEST RAP AND NAM12 1000MB CONDENSATION PRESSURE
DEFICIT PROGS SUGGEST THE MOST LIKELY AREA FOR SIGNIFICANT FOG TO
FORM WILL BE OVER SOUTHEAST GEORGIA...ESPECIALLY SOUTH OF THE I-16
CORRIDOR. THIS SEEMS REASONABLE GIVEN THE LACK OF CLOUD COVER AND
THERE ARE ALREADY SIGNALS OF LOW STRATUS BEGINNING TO DEVELOP.
WHILE SOME FOG IS LIKELY ACROSS SOUTHEAST SOUTH CAROLINA...INCOMING
DEBRIS CLOUDINESS COULD TEMPER THE COVERAGE THERE SOMEWHAT. WILL
CONTINUE TO HIGHLIGHT AREAS OF FOG IN THE GRIDDED AND TEXT
FORECASTS THROUGH SUNRISE. A DENSE FOG ADVISORY MAY VERY WELL BE
NEEDED FOR PARTS OF THE AREA OVER THE COMING HOURS.
THE KCLX RADAR IS PINNING LIGHT RETURNS OFF THE SOUTHERN SOUTH
CAROLINA COAST. THIS ACTIVITY IS LIKELY MILITARY CHAFF AND NOT
HYDROMETEORS PER DUAL-POL MULTI-LAYER CORRELATION COEFFICIENT
PRODUCTS. ISOLATED SHOWERS CONTINUE TO PERCOLATE OFF THE GEORGIA
COAST NEAR WEAK LOW PRESSURE.
TODAY...THE REGION WILL REMAIN ALONG THE FAR EASTERN PERIPHERY OF
A LARGE ANTICYCLONE CENTERED OVER THE CENTRAL PLAINS WITH AN
ADJACENT MID-LEVEL TROUGH POSITIONED WELL OFFSHORE OVER THE
SOUTHWEST ATLANTIC. AS THE SURFACE...DUAL LOW PRESSURE AREAS ARE
NOTED ALONG A BROAD SURFACE TROUGH THAT EXTENDS FROM THE EASTERN
GULF OF MEXICO...THROUGH CENTRAL FLORIDA AND INTO THE GULF STREAM
OFF THE SOUTH CAROLINA/GEORGIA COASTS. THE LOW CENTERS WILL REMAIN
ILL-DEFINED TODAY AND LIKELY DISSIPATE AT SOME POINT DURING THE
NEXT 12 HOURS AS THE SURFACE TROUGH LINGERS. IT WILL BE ANOTHER
HOT AND MUGGY DAY FOR THE LOWCOUNTRY AND COASTAL EMPIRE WITH ONLY
ISOLATED SHOWERS/TSTMS EXPECTED TO DEVELOP THIS AFTERNOON. LOW-
LEVEL CONVERGENCE ALONG THE SEA BREEZE WILL BE RATHER WEAK SO ANY
CONVECTION SHOULD DEVELOP FARTHER INLAND COMPARED TO YESTERDAY
AFTERNOON. TWENTY PERCENT POPS LOOK REASONABLE IN THIS SYNOPTIC
REGIME AND MAINLY CONFINED TO AREAS WEST OF THE I-95 CORRIDOR.
HIGHS WILL RANGE FROM THE MID-UPPER 90S INLAND TO THE UPPER 80S-
LOWER 90S AT THE COAST WITH MID 80S AT THE BEACHES. HEAT INDICES
WILL APPROACH 103-106 IN A FEW LOCATIONS THIS AFTERNOON WHICH IS
BELOW THE HEAT ADVISORY CRITERIA OF 110.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
TONIGHT...CUMULUS WILL DISSIPATE QUICKLY AFTER SUNSET WITH ONLY
CIRRUS EXPECTED TO TRAVERSE THE SKY THROUGH THE NIGHT. SOME
STRATOCUMULUS WILL LIKELY LINGER OVER THE COAST WITH THE ONSHORE
FLOW. SOME FOG AND STRATUS IS LIKELY FORM AGAIN EARLY WEDNESDAY
MORNING...BUT ITS POTENTIAL SEVERITY IS A BIT UNKNOWN THIS FAR
OUT...ESPECIALLY GIVEN THE MODELS HAVE BEEN PERFORMING WELL BELOW
AVERAGE ON CAPTURE FOG TRENDS. LOWS WILL RANGE FROM THE LOWER 70S
INLAND TO THE MID 70S AT THE COAST WITH UPPER 70S/NEAR 80 AT THE
BEACHES AND DOWNTOWN CHARLESTON.
WEDNESDAY MORNING...ANY FOG/STRATUS WILL GIVE WAY TO PARTLY SUNNY
CONDITIONS. THEN...ISOLATED/SCATTERED DIURNAL THUNDERSTORMS ARE
EXPECTED TO DEVELOP DURING THE AFTERNOON AS A CHANNEL OF
VORTICITY/DEFORMATION ON THE EASTERN PERIPHERY OF AN INLAND UPPER
RIDGE INTERACTS WITH THE SEA BREEZE. POPS ARE GRADUATED FROM SLIGHT
CHANCE NEAR THE COAST TO CHANCE ALONG/WEST OF I-95 WHERE HIGHER
PWATS WILL RESIDE. OTHERWISE...EXPECT HIGH TEMPERATURES IN THE
LOWER/MID 90S INLAND AND 80S ALONG THE IMMEDIATE COAST.
WEDNESDAY NIGHT...DIURNAL CONVECTION SHOULD DISSIPATE OVER
LAND...ALTHOUGH THE GFS MAINTAINS CONVECTION NEAR THE COAST INTO THE
OVERNIGHT HOURS. MEANWHILE...MODEL SOUNDINGS AND THE 28/00Z NAM PROG
OF 1000 MB PRESSURE CONDENSATION DEFICITS SUGGESTS THAT FOG/STRATUS
COULD DEVELOP. TEMPERATURES SHOULD BOTTOM OUT IN THE LOWER TO MID
70S INLAND AND 75-80F CLOSE TO THE COAST.
EXPECT A SIMILAR REGIME THURSDAY. ANY MORNING FOG/STRATUS WILL GIVE
WAY TO PARTLY SUNNY SKIES...AND ISOLATED/SCATTERED DIURNAL
SHOWERS/THUNDERSTORMS SHOULD AGAIN DEVELOP ESPECIALLY DURING THE
AFTERNOON/EARLY EVENING. ACCOUNTING FOR THE EAST/WEST MOISTURE
GRADIENT WHICH SHOULD PERSIST ACROSS THE REGION...POPS ARE TAPERED
FROM SLIGHT CHANCE ALONG THE COAST TO CHANCE INLAND. OTHERWISE...
EXPECT HIGH TEMPS IN THE LOWER/MID 90S INLAND AND 80S ON THE
BEACHES.
THE POTENTIAL FOR STRATUS/FOG COULD DIMINISH THURSDAY NIGHT.
OTHERWISE...DIURNAL/EVENING CONVECTION SHOULD GRADUALLY DISSIPATE.
DESPITE THE 28/00Z GFS DEPICTION OF PERSISTENT CONVECTION
OVERNIGHT...LOWERED POPS BELOW 15 PERCENT WITH NO MENTION OF
PRECIPITATION OVER LAND AFTER MIDNIGHT.
PER LATEST MODEL TRENDS...FRIDAY SHOULD PROVE TO BE THE MOST
CONVECTIVELY ACTIVE DAY OF THIS FORECAST PERIOD. A TROUGH AT THE
SURFACE AND ALOFT WILL BEGIN TO TAKE SHAPE OVER THE REGION...AND A
PLUME OF DEEP MOISTURE FEATURING PWATS WELL OVER 2 INCHES/1 TO 2
STANDARD DEVIATIONS ABOVE NORMAL WILL SAG INTO THE REGION FROM THE
NORTH. THIS REGIME SHOULD READILY SUPPORT AT LEAST SCATTERED/
NUMEROUS SHOWERS/THUNDERSTORMS FRIDAY AFTERNOON. IN GENERAL...LATEST
GUIDANCE POINTS TO HIGHEST POPS ACROSS INTERIOR/NORTHERN
COUNTIES...THUS INTRODUCED LIKELY POPS THERE FRIDAY AFTERNOON.
HOWEVER...THIS SCENARIO WILL LIKELY CHANGE OVER THE NEXT FEW DAYS.
MEANWHILE...FRIDAY TEMPERATURES ARE TRICKY DUE TO UNCERTAINTY
REGARDING THE TIMING OF CONVECTION INITIATION. THUS...DID NOT MAKE
SIGNIFICANT CHANGES TO ONGOING TEMPERATURES IN THE LOWER/MID 90S
INLAND AND 80S ALONG THE COAST...BUT CONVECTION/ASSOCIATED CLOUD
COVER COULD GREATLY ALTER MIDDAY/AFTERNOON TEMPERATURES.
THE POTENTIAL FOR SEVERE WEATHER/LOCALLY HEAVY RAINFALL APPEARS
LIMITED WITHIN DIURNAL CONVECTION WEDNESDAY AND THURSDAY.
FRIDAY...THE POTENTIAL FOR SEVERE WEATHER SHOULD INCREASE...ALTHOUGH
FORECAST INSTABILITY IS NOT OVERLY IMPRESSIVE. OF GREATER
CONCERN...HIGH PWATS AND WEAK TROPOSPHERIC FLOW COULD PROMOTE
LOCALLY EXCESSIVE RAINFALL BEGINNING FRIDAY. IN PARTICULAR...
IF HEAVY RAIN FALLS ALONG THE COAST DURING ELEVATED HIGH TIDES...
THE POTENTIAL FOR LOCALIZED FLOODING COULD BE ENHANCED.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
AN UNSETTLED REGIME FEATURING ABOVE NORMAL POPS AND BELOW NORMAL
HIGH TEMPERATURES WILL PREVAIL THROUGH THIS PERIOD AS A DEEP TROUGH
OF LOW PRESSURE/AN ASSOCIATED PLUME OF ENHANCED MOISTURE/HIGH PWATS
RESIDES OVER THE REGION. SEVERAL FACTORS REDUCE CONFIDENCE REGARDING
FORECAST DETAILS...MAINLY RELATED TO THE STRENGTH OF THE BERMUDA
HIGH AND THE INTERACTION OF THE ATLANTIC RIDGE WITH THE TROUGH OVER
THE SOUTHEAST. IF THE ATLANTIC RIDGE DOES NOT STRENGTHEN...THE
TROUGH AND DEEPEST MOISTURE REMAIN OVER THE REGION OR EVEN PUSH
SLIGHTLY OFFSHORE AS DEPICTED BY THE 28/00Z OPERATIONAL EUROPEAN. ON
THE OTHER HAND...IF THE BERMUDA HIGH EXPANDS...THE TROUGH AND DEEPER
MOISTURE COULD BE SHUNTED INLAND...SUPPORTING A SUBTLE
WARMING/DRYING TREND ESPECIALLY EARLY NEXT WEEK. DUE TO UNCERTAINTY
REGARDING THE SYNOPTIC SCENARIO AND THE USUAL MESOSCALE UNCERTAINTY
REGARDING CONVECTION EVOLUTION...CONTINUED TO CAP MAXIMUM POPS
AROUND 50 PERCENT THIS WEEKEND INTO EARLY NEXT WEEK. EVENTUALLY...
PERIODS OF HIGHER POPS WILL LIKELY BE REQUIRED FOR SOME OR ALL OF
THE FORECAST AREA.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
THE PRIMARY CONCERN IS FOG/STRATUS THROUGH SUNRISE. CONDITIONS
APPEAR SIMILAR TO YESTERDAY MORNING WHERE DENSE FOG WAS FAIRLY
WIDESPREAD. LATEST HIGH RESOLUTION GUIDANCE FAVORS KSAV FOR THE
HIGHER PROBABILITIES FOR IFR OR LOWER CONDITIONS PRIOR TO
SUNRISE...ASSUMING A BATCH OF MID-LEVEL CLOUDS MOVES INTO THE KCHS
AREA AS EXPECTED. WILL GO AHEAD AND SHOW PREVAILING LOW-END MVFR
VSBYS 09-1330Z WITH TEMPO IFR FROM 10-12Z...BUT WILL NOT ESTABLISH
CIGS ATTM. AT KCHS...WILL KEEP CONDITIONS LOW-END MVFR. AMENDMENTS
WILL MOST CERTAINLY BE NEEDED THROUGHOUT THE EARLY MORNING AS
TRENDS BECOME MORE APPARENT. VFR WILL PREVAIL ONCE ANY FOG/STRATUS
MIXES OUT BY 13-14Z. ONLY ISOLATED SHOWERS AND TSTMS EXPECTED
TUESDAY AFTERNOON. COVERAGE TOO LOW TO JUSTIFY ANY MENTION IN THE
00Z TAFS.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS WILL BE POSSIBLE IN
STRATUS/FOG WEDNESDAY MORNING. A LOW PROBABILITY FOR FLIGHT
RESTRICTIONS EXISTS WITHIN AFTERNOON THUNDERSTORMS WEDNESDAY AND
THURSDAY. THE PROBABILITY FOR THUNDERSTORMS/ASSOCIATED FLIGHT
RESTRICTIONS WILL INCREASE FRIDAY AND SATURDAY.
&&
.MARINE...
TODAY...PATCHY FOG IS POSSIBLE IN THE CHARLESTON HARBOR THIS
MORNING. APPROACHING DEBRIS CLOUDINESS SHOULD KEEP THE FOG IN
CHECK...BUT TRENDS WILL BE MONITORED. A MORE UNIFORM EAST FLOW
IS EXPECTED TO DEVELOP BY THIS AFTERNOON AS THE SEA BREEZE
DEVELOPS AND WEAK LOW PRESSURE PASSES OFF TO THE EAST. WINDS LOOK
TO REMAIN 10 KT OR LESS WITH SEAS AVERAGING 2-3 FT.
TONIGHT...EAST WINDS WILL TIP BACK TO THE NORTHEAST OVERNIGHT WITH
SPEEDS AROUND 5 KT. SEAS WILL AVERAGE 2-3 FT...EXCEPT 1-2 FT OVER
THE GEORGIA NEARSHORE WATERS.
WEDNESDAY THROUGH SUNDAY...ONSHORE WINDS WILL PERSIST WEDNESDAY
THROUGH THURSDAY...WITH SOME ENHANCEMENT OCCURRING DURING
AFTERNOON SEABREEZE CIRCULATIONS. IN GENERAL...WINDS WILL REMAIN
AT OR BELOW 15 KTS WITH SEAS NO HIGHER THAN 2-4 FT...HIGHEST
BEYOND 20 NM. AFTER A TRANSITION THROUGH A WEAK PRESSURE PATTERN
THURSDAY NIGHT AND FRIDAY...WINDS SHOULD BECOME SOUTH/SOUTHWEST BY
THIS WEEKEND...PERHAPS INCREASING TO 15-20 KT IN SOME AREAS WITH
THE AFTERNOON SEABREEZE AND WITH NOCTURNAL SURGES. SEAS SHOULD
REMAIN BETWEEN 2-4 FT NEARSHORE AND 4-5 FT BEYOND 20 NM THIS
WEEKEND. THUNDERSTORMS COULD PRODUCE LOCAL HAZARDS AND COULD
GREATLY ALTER SYNOPTIC WINDS ESPECIALLY LATE WEEK THROUGH THIS
WEEKEND.
&&
.TIDES/COASTAL FLOODING...
TIDAL DEPARTURES ARE EXPECTED TO HOLD FAIRLY STEADY FOR THE NEXT
12 HOURS OR SO. CURRENT EXTRATROPICAL SURGE GUIDANCE TAKE TIDE
LEVELS VERY NEAR 7.0 FT MLLW IN THE CHARLESTON HARBOR FOR HIGH
TIDE THIS EVENING...WHICH IS THE THRESHOLD FOR SHALLOW COASTAL
FLOODING FOR THE LOWER SOUTH CAROLINA COAST. A COASTAL FLOOD
ADVISORY MAY BE NEEDED FOR PARTS OF THE LOWER SOUTH CAROLINA COAST
IF THIS TREND CONTINUES...BUT THE EVENT LOOKS MARGINAL AT BEST.
EVEN IF TIDE LEVELS DO NOT REACH 7.0 FT MLLW IN THE CHARLESTON
HARBOR...SOME VERY MINOR SALT WATER INUNDATION IS LIKELY TO OCCUR
IN SOME OF THE NORMALLY FLOOD PRONE AREAS OF DOWNTOWN CHARLESTON...
ASSUMING LEVELS SURPASS 6.8 FT MLLW. THERE ARE NO CONCERNS FOR
SHALLOW COASTAL FLOODING ALONG THE GEORGIA COAST WITH THIS
EVENING/S HIGH TIDE CYCLE.
ELEVATED HIGH TIDE LEVELS WILL PREVAIL THROUGH THIS WEEKEND/INTO
EARLY NEXT WEEK DUE TO THE UPCOMING JULY 31 FULL MOON/AUGUST 2
PERIGEE AND PERSISTENT ONSHORE WINDS. EXTRATROPICAL SURGE GUIDANCE
CONTINUES TO FORECAST A SERIES OF SHALLOW SALT WATER FLOODING
EVENTS...ESPECIALLY AROUND THE TIMES OF THE EVENING HIGH TIDES.
EVENING HIGH TIDES COULD ATTAIN COASTAL FLOOD ADVISORY LEVELS ALONG
THE SOUTH CAROLINA COAST WEDNESDAY INTO EARLY NEXT WEEK AND ALONG
THE GEORGIA COAST WEDNESDAY OR THURSDAY THROUGH AT LEAST THIS
WEEKEND. WILL CONTINUE TO HIGHLIGHT THE POTENTIAL FOR SHALLOW SALT
WATER FLOODING/COASTAL FLOOD ADVISORIES WITHIN THE HAZARDOUS WEATHER
OUTLOOK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/SPR
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1103 AM CDT TUE JUL 28 2015
.UPDATE...
ISSUED AT 1053 AM CDT TUE JUL 28 2015
A FEW ISOLATED THUNDERSTORMS OUT AHEAD OF THE COMPLEX IN EASTERN
IA THIS MORNING MOVING THROUGH NRN KNOX AND NRN PEORIA COUNTIES
ALONG AND NW OF THE IL RIVER VALLEY. OTHER THAN THAT, WEAK FRONTAL
BOUNDARY DRAPED ACROSS THE SOUTHERN TIER OF THE STATE, WITH VERY
LITTLE IN THE WAY OF AIRMASS DIFFERENTIATION IN HUMIDITY, BUT THE
TEMPS ARE A FEW DEGREES WARMER TO THE SOUTH. MOVEMENT OF THAT
WARMER AIRMASS IS NOT QUICK AS UPPER LEVELS ARE DOMINATED BY RIDGE
BUILDING AND WEAK FLOW. SHORT RANGE MODELS CONTINUE TO WEAKEN AND
ERODE THE SHOWERS TO THE NW AS THEY APPROACH ILX AND AS A RESULT,
ONLY MINOR SHIFTS TO THE SHORT TERM FORECAST ARE NECESSARY.
&&
.SHORT TERM...(TODAY)
ISSUED AT 257 AM CDT TUE JUL 28 2015
MAIN CONCERN FOR TODAY REMAINS WITH THE HEAT. NO CHANGES PLANNED
FOR THE TIMING OR ALIGNMENT OF THE HEAT ADVISORY. DEW POINTS
ALREADY IN THE MID 70S ACROSS WESTERN MISSOURI...AND THIS WILL BE
ADVECTING OUR WAY THE NEXT SEVERAL HOURS. WILL LIKELY SEE SOME
UPPER 70S DEW POINTS BY LATE AFTERNOON...ESPECIALLY ACROSS THE
SOUTHWEST CWA. THIS TRANSLATES TO HEAT INDEX OF 105-110 FROM ABOUT
GALESBURG-EFFINGHAM WESTWARD...WITH THE HIGHER READINGS TOWARD THE
ILLINOIS RIVER VALLEY NEAR HAVANA AND BEARDSTOWN.
STILL SOME CONCERN ABOUT SOME THUNDERSTORM DEVELOPMENT TODAY.
SURFACE OBSERVATIONS SHOWING A WEAK BOUNDARY PERSISTING ALONG THE
OHIO VALLEY NORTHWEST NEAR THE ILLINOIS/MISSOURI BORDER. THIS
WOULD SERVE AS ONE FOCUS FOR ANY ISOLATED DEVELOPMENT. OF MORE
CONCERN IS THE MCS CURRENTLY ROLLING ACROSS EASTERN SOUTH DAKOTA.
HIGH-RESOLUTION MODELS SUCH AS THE ARW...HRRR AND HOP-WRF ARE
DOING A RESPECTABLE JOB WITH THE SYSTEM THUS FAR...AND SHOW SOME
OF THE REMNANTS MAKING IT AS FAR AS GALESBURG BY EARLY AFTERNOON.
THE NMM MOSTLY FIZZLES IT OUT BEFORE REACHING US...WHILE THE
NAM-12 IS CASUALLY IGNORING ITS EXISTENCE ALTOGETHER. RECENT
SOUTHWARD DEVELOPMENT ALONG THE NEBRASKA/IOWA BORDER WOULD LEND
SOME CREDENCE TOWARD THE HRRR SOLUTION...ALTHOUGH THERE WILL BE
SOME WEAK CAPPING TO GET THROUGH FIRST BETWEEN HERE AND THERE.
WILL STICK WITH ISOLATED STORMS FOR NOW...AS EARLY AS MID-MORNING
ACROSS THE WESTERN CWA AND ACROSS MOST OF THE AREA DURING THE
AFTERNOON.
.LONG TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 257 AM CDT TUE JUL 28 2015
MAIN COLD FRONT STILL SCHEDULED TO CROSS THE FORECAST AREA
WEDNESDAY MORNING AND AFTERNOON. MAIN ORGANIZATION TO CONVECTIVE
CLUSTER SHOULD TAKE PLACE ACROSS CENTRAL/SOUTHERN IOWA THIS
AFTERNOON AND ROLL EAST-SOUTHEAST. WILL FOCUS HIGHER POP`S
BEGINNING MID-LATE EVENING NORTHWEST OF THE ILLINOIS RIVER...AND
SHIFTING IT AS FAR AS CHAMPAIGN AND MATTOON BY LATE NIGHT. HAVE
KEPT THE SOUTHEAST CWA LARGELY DRY UNTIL CLOSER TO SUNRISE... WITH
THE HIGHER POP`S IN THAT AREA LATER ON WEDNESDAY. SIGNIFICANTLY
DRIER AIR WILL BE PUSHING IN DURING THE AFTERNOON BEHIND THE
FRONT...BUT MID 70S DEW POINTS ARE STILL LIKELY ACROSS THE EASTERN
CWA INTO THE AFTERNOON. MAY NEED ANOTHER HEAT ADVISORY SOUTH OF
I-70 ON WEDNESDAY...BUT THIS IS BORDERLINE WITH THE INCREASE IN
CLOUDS AND CONVECTION...SO WILL NOT PUT AN EXTENSION THERE YET.
REMAINDER OF THE WEEK LOOKS DRY AND MORE COMFORTABLE...WITH A
NORTHWEST UPPER FLOW AS THE RIDGE REBUILDS ACROSS THE WEST COAST.
GFS SHOWS NO SIGNIFICANT CHANGE IN THAT PATTERN FOR SEVERAL DAYS
AND IN FACT BRINGS A LOBE OF MUCH COOLER AIR INTO THE MIDWEST
EARLY NEXT WEEK...WHILE THE ECMWF IS WARMER AS THE RIDGE ONLY
GRADUALLY FLATTENS. HAVE GONE THE WARMER SOLUTION ALTHOUGH
TEMPERATURES WILL STILL BE NEAR NORMAL...GENERALLY HIGHS IN THE
MID 80S FROM THURSDAY ONWARD. NEXT CONCERN FOR RAIN WILL BE LATE
WEEKEND...AS AN UPPER TROUGH SWINGS THROUGH THE GREAT LAKES.
WEST-EAST AXIS OF HIGH PRESSURE AT THE SURFACE WILL BE PRESENT
ACROSS THE OHIO VALLEY AT THE TIME. THE ECMWF KEEPS IT STRONG
ENOUGH TO PREVENT THE SURFACE FRONT FROM MAKING MUCH PROGRESS
SOUTH OF I-80...WHILE THE GFS GETS THE BOUNDARY THROUGH IN A
WEAKENING STATE. HAVE CAPPED POP`S AT SLIGHT CHANCES ACROSS THE
NORTH ON SUNDAY...BUT BROUGHT SOME 30% CHANCES IN FOR MONDAY AS
ANOTHER UPPER TROUGH ARRIVES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 545 AM CDT TUE JUL 28 2015
SOME MVFR VISIBILITIES OF 2-4SM OCCURRING EARLY THIS MORNING IN
THE HUMID AIR MASS...BUT SO FAR LOWER VISIBILITIES HAVE HELD OFF
LIKELY DUE TO SOME HIGH CLOUD REMNANTS FROM OVERNIGHT CONVECTION.
CONDITIONS SHOULD IMPROVE OVER THE NEXT COUPLE HOURS.
HAVE SOME CONCERNS ABOUT ISOLATED STORMS ALONG A WEAK BOUNDARY
THAT EXTENDS FROM NEAR KMLI-KSPI-KMVN. EARLIER HIGH-RESOLUTION
MODEL GUIDANCE HAD BEEN SUGGESTING SOME STORMS AS EARLY AS MID
MORNING WEST OF THE BOUNDARY...BUT HAVE EASED OFF RECENTLY. MORE
CONCERNING IS A LARGE THUNDERSTORM COMPLEX MOVING THROUGH IOWA...
WITH AN ASSOCIATED WING OF STORMS FROM KCID NORTHWEST. OVERALL
WEAKENING OF THE STORMS HAS BEEN SEEN ON INFRARED SATELLITE
RECENTLY...AND THE LEADING WING SHOULD TRACK NORTH OF THE CENTRAL
ILLINOIS TAF SITES. SO...AM PLANNING TO KEEP THE TAF SITES DRY
DURING THE DAY. THUNDER CHANCES WILL BE INCREASING FROM WEST TO
EAST TONIGHT AS A COLD FRONT APPROACHES FROM THE WEST. THE FRONT
SHOULD BE PASSING THROUGH THE TAF SITES AFTER 12Z WITH A WIND
SHIFT TO THE NORTHWEST.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ILZ027>031-036>038-
040>044-047>054-056-061>063-066>068-071>073.
&&
$$
UPDATE...HJS
SHORT TERM...GEELHART
LONG TERM...GEELHART
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
545 AM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY)
ISSUED AT 257 AM CDT TUE JUL 28 2015
MAIN CONCERN FOR TODAY REMAINS WITH THE HEAT. NO CHANGES PLANNED
FOR THE TIMING OR ALIGNMENT OF THE HEAT ADVISORY. DEW POINTS
ALREADY IN THE MID 70S ACROSS WESTERN MISSOURI...AND THIS WILL BE
ADVECTING OUR WAY THE NEXT SEVERAL HOURS. WILL LIKELY SEE SOME
UPPER 70S DEW POINTS BY LATE AFTERNOON...ESPECIALLY ACROSS THE
SOUTHWEST CWA. THIS TRANSLATES TO HEAT INDEX OF 105-110 FROM ABOUT
GALESBURG-EFFINGHAM WESTWARD...WITH THE HIGHER READINGS TOWARD THE
ILLINOIS RIVER VALLEY NEAR HAVANA AND BEARDSTOWN.
STILL SOME CONCERN ABOUT SOME THUNDERSTORM DEVELOPMENT TODAY.
SURFACE OBSERVATIONS SHOWING A WEAK BOUNDARY PERSISTING ALONG THE
OHIO VALLEY NORTHWEST NEAR THE ILLINOIS/MISSOURI BORDER. THIS
WOULD SERVE AS ONE FOCUS FOR ANY ISOLATED DEVELOPMENT. OF MORE
CONCERN IS THE MCS CURRENTLY ROLLING ACROSS EASTERN SOUTH DAKOTA.
HIGH-RESOLUTION MODELS SUCH AS THE ARW...HRRR AND HOP-WRF ARE
DOING A RESPECTABLE JOB WITH THE SYSTEM THUS FAR...AND SHOW SOME
OF THE REMNANTS MAKING IT AS FAR AS GALESBURG BY EARLY AFTERNOON.
THE NMM MOSTLY FIZZLES IT OUT BEFORE REACHING US...WHILE THE
NAM-12 IS CASUALLY IGNORING ITS EXISTENCE ALTOGETHER. RECENT
SOUTHWARD DEVELOPMENT ALONG THE NEBRASKA/IOWA BORDER WOULD LEND
SOME CREDENCE TOWARD THE HRRR SOLUTION...ALTHOUGH THERE WILL BE
SOME WEAK CAPPING TO GET THROUGH FIRST BETWEEN HERE AND THERE.
WILL STICK WITH ISOLATED STORMS FOR NOW...AS EARLY AS MID-MORNING
ACROSS THE WESTERN CWA AND ACROSS MOST OF THE AREA DURING THE
AFTERNOON.
.LONG TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 257 AM CDT TUE JUL 28 2015
MAIN COLD FRONT STILL SCHEDULED TO CROSS THE FORECAST AREA
WEDNESDAY MORNING AND AFTERNOON. MAIN ORGANIZATION TO CONVECTIVE
CLUSTER SHOULD TAKE PLACE ACROSS CENTRAL/SOUTHERN IOWA THIS
AFTERNOON AND ROLL EAST-SOUTHEAST. WILL FOCUS HIGHER POP`S
BEGINNING MID-LATE EVENING NORTHWEST OF THE ILLINOIS RIVER...AND
SHIFTING IT AS FAR AS CHAMPAIGN AND MATTOON BY LATE NIGHT. HAVE
KEPT THE SOUTHEAST CWA LARGELY DRY UNTIL CLOSER TO SUNRISE... WITH
THE HIGHER POP`S IN THAT AREA LATER ON WEDNESDAY. SIGNIFICANTLY
DRIER AIR WILL BE PUSHING IN DURING THE AFTERNOON BEHIND THE
FRONT...BUT MID 70S DEW POINTS ARE STILL LIKELY ACROSS THE EASTERN
CWA INTO THE AFTERNOON. MAY NEED ANOTHER HEAT ADVISORY SOUTH OF
I-70 ON WEDNESDAY...BUT THIS IS BORDERLINE WITH THE INCREASE IN
CLOUDS AND CONVECTION...SO WILL NOT PUT AN EXTENSION THERE YET.
REMAINDER OF THE WEEK LOOKS DRY AND MORE COMFORTABLE...WITH A
NORTHWEST UPPER FLOW AS THE RIDGE REBUILDS ACROSS THE WEST COAST.
GFS SHOWS NO SIGNIFICANT CHANGE IN THAT PATTERN FOR SEVERAL DAYS
AND IN FACT BRINGS A LOBE OF MUCH COOLER AIR INTO THE MIDWEST
EARLY NEXT WEEK...WHILE THE ECMWF IS WARMER AS THE RIDGE ONLY
GRADUALLY FLATTENS. HAVE GONE THE WARMER SOLUTION ALTHOUGH
TEMPERATURES WILL STILL BE NEAR NORMAL...GENERALLY HIGHS IN THE
MID 80S FROM THURSDAY ONWARD. NEXT CONCERN FOR RAIN WILL BE LATE
WEEKEND...AS AN UPPER TROUGH SWINGS THROUGH THE GREAT LAKES.
WEST-EAST AXIS OF HIGH PRESSURE AT THE SURFACE WILL BE PRESENT
ACROSS THE OHIO VALLEY AT THE TIME. THE ECMWF KEEPS IT STRONG
ENOUGH TO PREVENT THE SURFACE FRONT FROM MAKING MUCH PROGRESS
SOUTH OF I-80...WHILE THE GFS GETS THE BOUNDARY THROUGH IN A
WEAKENING STATE. HAVE CAPPED POP`S AT SLIGHT CHANCES ACROSS THE
NORTH ON SUNDAY...BUT BROUGHT SOME 30% CHANCES IN FOR MONDAY AS
ANOTHER UPPER TROUGH ARRIVES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 545 AM CDT TUE JUL 28 2015
SOME MVFR VISIBILITIES OF 2-4SM OCCURRING EARLY THIS MORNING IN
THE HUMID AIR MASS...BUT SO FAR LOWER VISIBILITIES HAVE HELD OFF
LIKELY DUE TO SOME HIGH CLOUD REMNANTS FROM OVERNIGHT CONVECTION.
CONDITIONS SHOULD IMPROVE OVER THE NEXT COUPLE HOURS.
HAVE SOME CONCERNS ABOUT ISOLATED STORMS ALONG A WEAK BOUNDARY
THAT EXTENDS FROM NEAR KMLI-KSPI-KMVN. EARLIER HIGH-RESOLUTION
MODEL GUIDANCE HAD BEEN SUGGESTING SOME STORMS AS EARLY AS MID
MORNING WEST OF THE BOUNDARY...BUT HAVE EASED OFF RECENTLY. MORE
CONCERNING IS A LARGE THUNDERSTORM COMPLEX MOVING THROUGH IOWA...
WITH AN ASSOCIATED WING OF STORMS FROM KCID NORTHWEST. OVERALL
WEAKENING OF THE STORMS HAS BEEN SEEN ON INFRARED SATELLITE
RECENTLY...AND THE LEADING WING SHOULD TRACK NORTH OF THE CENTRAL
ILLINOIS TAF SITES. SO...AM PLANNING TO KEEP THE TAF SITES DRY
DURING THE DAY. THUNDER CHANCES WILL BE INCREASING FROM WEST TO
EAST TONIGHT AS A COLD FRONT APPROACHES FROM THE WEST. THE FRONT
SHOULD BE PASSING THROUGH THE TAF SITES AFTER 12Z WITH A WIND
SHIFT TO THE NORTHWEST.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING
FOR ILZ027>031-036>038-040>044-047>054-056-061>063-066>068-
071>073.
&&
$$
SHORT TERM...GEELHART
LONG TERM...GEELHART
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
257 AM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY)
ISSUED AT 257 AM CDT TUE JUL 28 2015
MAIN CONCERN FOR TODAY REMAINS WITH THE HEAT. NO CHANGES PLANNED
FOR THE TIMING OR ALIGNMENT OF THE HEAT ADVISORY. DEW POINTS
ALREADY IN THE MID 70S ACROSS WESTERN MISSOURI...AND THIS WILL BE
ADVECTING OUR WAY THE NEXT SEVERAL HOURS. WILL LIKELY SEE SOME
UPPER 70S DEW POINTS BY LATE AFTERNOON...ESPECIALLY ACROSS THE
SOUTHWEST CWA. THIS TRANSLATES TO HEAT INDEX OF 105-110 FROM ABOUT
GALESBURG-EFFINGHAM WESTWARD...WITH THE HIGHER READINGS TOWARD THE
ILLINOIS RIVER VALLEY NEAR HAVANA AND BEARDSTOWN.
STILL SOME CONCERN ABOUT SOME THUNDERSTORM DEVELOPMENT TODAY.
SURFACE OBSERVATIONS SHOWING A WEAK BOUNDARY PERSISTING ALONG THE
OHIO VALLEY NORTHWEST NEAR THE ILLINOIS/MISSOURI BORDER. THIS
WOULD SERVE AS ONE FOCUS FOR ANY ISOLATED DEVELOPMENT. OF MORE
CONCERN IS THE MCS CURRENTLY ROLLING ACROSS EASTERN SOUTH DAKOTA.
HIGH-RESOLUTION MODELS SUCH AS THE ARW...HRRR AND HOP-WRF ARE
DOING A RESPECTABLE JOB WITH THE SYSTEM THUS FAR...AND SHOW SOME
OF THE REMNANTS MAKING IT AS FAR AS GALESBURG BY EARLY AFTERNOON.
THE NMM MOSTLY FIZZLES IT OUT BEFORE REACHING US...WHILE THE
NAM-12 IS CASUALLY IGNORING ITS EXISTENCE ALTOGETHER. RECENT
SOUTHWARD DEVELOPMENT ALONG THE NEBRASKA/IOWA BORDER WOULD LEND
SOME CREDENCE TOWARD THE HRRR SOLUTION...ALTHOUGH THERE WILL BE
SOME WEAK CAPPING TO GET THROUGH FIRST BETWEEN HERE AND THERE.
WILL STICK WITH ISOLATED STORMS FOR NOW...AS EARLY AS MID-MORNING
ACROSS THE WESTERN CWA AND ACROSS MOST OF THE AREA DURING THE
AFTERNOON.
&&
.LONG TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 257 AM CDT TUE JUL 28 2015
MAIN COLD FRONT STILL SCHEDULED TO CROSS THE FORECAST AREA
WEDNESDAY MORNING AND AFTERNOON. MAIN ORGANIZATION TO CONVECTIVE
CLUSTER SHOULD TAKE PLACE ACROSS CENTRAL/SOUTHERN IOWA THIS
AFTERNOON AND ROLL EAST-SOUTHEAST. WILL FOCUS HIGHER POP`S
BEGINNING MID-LATE EVENING NORTHWEST OF THE ILLINOIS RIVER...AND
SHIFTING IT AS FAR AS CHAMPAIGN AND MATTOON BY LATE NIGHT. HAVE
KEPT THE SOUTHEAST CWA LARGELY DRY UNTIL CLOSER TO SUNRISE... WITH
THE HIGHER POP`S IN THAT AREA LATER ON WEDNESDAY. SIGNIFICANTLY
DRIER AIR WILL BE PUSHING IN DURING THE AFTERNOON BEHIND THE
FRONT...BUT MID 70S DEW POINTS ARE STILL LIKELY ACROSS THE EASTERN
CWA INTO THE AFTERNOON. MAY NEED ANOTHER HEAT ADVISORY SOUTH OF
I-70 ON WEDNESDAY...BUT THIS IS BORDERLINE WITH THE INCREASE IN
CLOUDS AND CONVECTION...SO WILL NOT PUT AN EXTENSION THERE YET.
REMAINDER OF THE WEEK LOOKS DRY AND MORE COMFORTABLE...WITH A
NORTHWEST UPPER FLOW AS THE RIDGE REBUILDS ACROSS THE WEST COAST.
GFS SHOWS NO SIGNIFICANT CHANGE IN THAT PATTERN FOR SEVERAL DAYS
AND IN FACT BRINGS A LOBE OF MUCH COOLER AIR INTO THE MIDWEST
EARLY NEXT WEEK...WHILE THE ECMWF IS WARMER AS THE RIDGE ONLY
GRADUALLY FLATTENS. HAVE GONE THE WARMER SOLUTION ALTHOUGH
TEMPERATURES WILL STILL BE NEAR NORMAL...GENERALLY HIGHS IN THE
MID 80S FROM THURSDAY ONWARD. NEXT CONCERN FOR RAIN WILL BE LATE
WEEKEND...AS AN UPPER TROUGH SWINGS THROUGH THE GREAT LAKES.
WEST-EAST AXIS OF HIGH PRESSURE AT THE SURFACE WILL BE PRESENT
ACROSS THE OHIO VALLEY AT THE TIME. THE ECMWF KEEPS IT STRONG
ENOUGH TO PREVENT THE SURFACE FRONT FROM MAKING MUCH PROGRESS
SOUTH OF I-80...WHILE THE GFS GETS THE BOUNDARY THROUGH IN A
WEAKENING STATE. HAVE CAPPED POP`S AT SLIGHT CHANCES ACROSS THE
NORTH ON SUNDAY...BUT BROUGHT SOME 30% CHANCES IN FOR MONDAY AS
ANOTHER UPPER TROUGH ARRIVES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1246 AM CDT TUE JUL 28 2015
DENSE CIRRUS SHIELD LEFT BEHIND BY CONVECTION THAT DISSIPATED
THIS EVENING CONTINUES TO BLANKET CENTRAL ILLINOIS EARLY THIS
MORNING...HOWEVER IT IS BEGINNING TO CLEAR OUT NORTHWEST OF THE
ILLINOIS RIVER. MAIN SHORT-TERM AVIATION CONCERN WILL BE HOW
MUCH FOG WILL FORM BETWEEN NOW AND DAWN. WITH SKIES CLEARING FROM
WEST TO EAST AND CONTINUED VERY LIGHT E/NE WINDS...FOG WILL
DEVELOP EVERYWHERE. THINK IT WILL BE THICKEST WHERE LIGHT RAIN
OCCURRED LAST EVENING AND WHERE SKIES CLEAR EARLIEST. AS A
RESULT...HAVE HIT VSBY RESTRICTIONS HARDEST AT BOTH KPIA AND KSPI
AFTER 08Z/09Z. MODELS SUGGEST WIDELY SCATTERED CONVECTION MAY
DEVELOP ALONG THE STATIONARY FRONTAL BOUNDARY NEAR THE MISSISSIPPI
RIVER THIS MORNING. WHILE CONFIDENCE REMAINS LOW...HAVE OPTED TO
INCLUDE VCTS AT KSPI BETWEEN 12Z AND 17Z. AFTER THAT...MAINLY DRY
CONDITIONS ARE ANTICIPATED THROUGHOUT THE DAY BEFORE A COLD FRONT
APPROACHES BY MID TO LATE EVENING. HAVE INTRODUCED VCTS AT KPIA
AFTER 03Z...ALTHOUGH THE BEST FOCUS FOR THUNDER WILL LIKELY HOLD
OFF UNTIL AFTER 06Z.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING
FOR ILZ027>031-036>038-040>044-047>054-056-061>063-066>068-
071>073.
&&
$$
SHORT TERM...GEELHART
LONG TERM...GEELHART
AVIATION...BARNES
AREA FORECAST DISCUSSION
NWS DES MOINES IA
358 AM CDT TUE JUL 28 2015
.SHORT TERM /TODAY/...
ISSUED AT 358 AM CDT TUE JUL 28 2015
A VERY COMPLEX FORECAST FOR TODAY WITH MANY CONSIDERATIONS. FIRST
AND FOREMOST...OUR MESSY CONVECTIVE PATTERN CONTINUES AS WE
REMAIN WITHIN THE SAME SOUPY AIRMASS THAT HAS PERSISTED THIS
WEEKEND. REGIONAL RADAR CURRENTLY DEPICTS A LONG SQUALL LINE
STRETCHING DOWN THE EASTERN DAKOTAS AND INTO NORTHEASTERN
NEBRASKA...MOVING STEADILY EASTWARD TOWARD NORTHWESTERN IOWA.
AHEAD OF THIS LINE...SCATTERED THUNDERSTORMS ARE DEVELOPING ACROSS
ABOUT THE NORTHERN HALF OF IOWA WITHIN A BROAD WARM AIR ADVECTION
REGIME. RADAR TRENDS AND HIGH RESOLUTION MODEL FORECASTS SUPPORT A
CONTINUATION OF THESE SCATTERED STORMS UNTIL THE SQUALL LINE MOVES
ACROSS OUR NORTHERN COUNTIES LATER THIS MORNING. THERE IS LOWER
CONFIDENCE IN THE SOUTHERN HALF OR SO OF THE FORECAST AREA BEING
AFFECTED. IF THE STORMS DIVE DOWN THE INSTABILITY GRADIENT
DEPICTED BY MESOANALYSIS THEN THEY MAY REACH SOUTHERN
IOWA...HOWEVER WARMER AIR ALOFT IS WORKING IN FROM THE SOUTHWEST
AND SATELLITE IMAGERY SHOWS A DISTINCT LACK OF CONVECTIVE CLOUD
DEVELOPMENT IN THAT AREA. IT IS MORE LIKELY THAT THE SQUALL LINE
WILL AFFECT NORTHERN IOWA...LEAVING IN ITS WAKE SOME DEBRIS CLOUDS
AND REMNANT OUTFLOW BOUNDARIES AS WELL AS A GRADUALLY MODIFYING
COLD POOL BY AROUND MIDDAY.
IN THE SOUTH AND SOUTHEAST...IF CONVECTION REALLY DOES REMAIN
CONFINED TO OUR NORTH...TEMPERATURES WILL WARM INTO THE LOWER 90S
BY THIS AFTERNOON WITH DEWPOINTS IN THE MID 70S OR SO. THIS WILL
PRODUCE HEAT INDEX VALUES NEAR 105 DEGREES...AND JUSTIFIES THE
ISSUANCE OF A SMALL HEAT ADVISORY AGAINST THOSE ALREADY ISSUED BY
NEIGHBORING OFFICES AGAINST OUR SOUTHEASTERN CORNER. HOWEVER...IF
THE MORNING STORMS MAKE IT FURTHER SOUTH THAN EXPECTED THE
ADVISORY MAY NOT PAN OUT...AND CONVERSELY IF MORNING CONVECTIVE
DEBRIS REMAINS CONFINED TO NORTH OF HIGHWAY 30 THEN THE ADVISORY
MAY NEED TO BE EXPANDED NORTHWARD A BIT DURING THE DAY.
BY LATE THIS AFTERNOON AND EARLY EVENING AS WE REACH PEAK DIURNAL
HEATING TIME THE AFOREMENTIONED RESIDUAL OUTFLOW BOUNDARIES SHOULD
PROVIDE FOCI FOR ADDITIONAL THUNDERSTORM DEVELOPMENT WITHIN THE
VERY UNSTABLE AIRMASS PRECEDING OUR WELL ADVERTISED COOL FRONT
APPROACHING FROM SOUTH DAKOTA AS DISCUSSED IN THE LONG TERM
SECTION BELOW. THERE IS SOME UNCERTAINTY REGARDING LOCATION OF
THIS REDEVELOPMENT CONTINGENT ON THE PATH MORNING STORMS
TAKE...BUT ANY STORMS THAT DO DEVELOP LATE IN THE DAY WILL
CERTAINLY BE WITHIN A FAVORABLE SEVERE WEATHER ENVIRONMENT AS
OUTLINED BY SPC PRODUCTS. HAVE MAINTAINED LIKELY POPS AFTER ABOUT
22Z TO ACCOUNT FOR THIS.
.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 358 AM CDT TUE JUL 28 2015
MAIN FORECAST CONCERN WAS FOCUSED ON COLD FRONT TO SWEEP ACROSS
THE STATE TONIGHT AND THE CONVECTION IT WILL BRING TO THE FORECAST
AREA. MODELS ARE IN OKAY AGREEMENT WITH THE TIMING OF THE COLD
FRONT TONIGHT WITH THE 28.00Z NAM THE SLOWEST MODEL AND NOT
INITIALIZING WELL THIS MORNING...THUS KEPT IT AS THE OUTLIER
TONIGHT INTO TOMORROW AND LEANED TOWARD THE GFS/ECMWF.
TONIGHT THROUGH WEDNESDAY...CONVECTION WILL BE ONGOING THIS
EVENING WITH THE PROGRESSION OF THE COLD FRONT ENTERING THE
WESTERN TO NORTHWESTERN PORTION OF THE CWA. DEEP LAYER SHEAR AHEAD
OF THE FRONT IS MAINLY UNIDIRECTIONAL BUT STRONG ENOUGH TO
SUSTAIN A COLD POOL. INSTABILITY IS PLENTIFUL WITH MUCAPE VALUES
RANGING FROM 1500-3500J/KG PER GFS/ECMWF. MCS MAINTENANCE
PROBABILITY VIA THE ECMWF/GFS ARE OVER 40 PERCENT WITH GFS AS
HIGH AS 90 THIS EVENING. CONFIDENCE STORMS WILL BE MOVING ACROSS
CENTRAL DURING MUCH OF THE EVENING BEFORE CLEARING THE FORECAST
AREA B/T 06-09Z WEDNESDAY. LOWER CONFIDENCE IS WIDESPREAD SEVERE
WEATHER...BUT STILL CANNOT RULE OUT A FEW STORMS PRODUCING STRONG
WINDS/LARGE HAIL EARLY IN THE EVENING WITH THE SHEAR AND
INSTABILITY AVAILABLE. THE OTHER THREAT IS HEAVY RAIN WITH STRONG
MOISTURE TRANSPORT VECTORS AND THETA-E ADVECTION INTO THE STATE
AHEAD OF THE FRONT COMBINED WITH THE DEEP WARM LAYER CLOUD DEPTHS
AND PRECIPITABLE WATER VALUES FROM 2 TO 2.4 INCHES. ISOLATED AREAS
OF FLASH FLOODING COULD POSE AN ISSUE TONIGHT IF ANY TRAINING
OCCURS ON TOP OF THE AREAS THAT WERE HIT WITH HEAVY RAIN MONDAY
AND OVER THE WEEKEND.
COLD FRONT WILL BRING SOME MUCH NEEDED COOLER AND DRIER AIR INTO
THE STATE OVERNIGHT TONIGHT THROUGHOUT THE DAY WEDNESDAY.
WEDNESDAY LOOKS TO BE A LITTLE BREEZY...ESPECIALLY ACROSS THE
NORTH WHERE PRESSURE GRADIENT AND SLIGHTLY DEEPER MIXING IS
ANTICIPATED. HOWEVER...SUB-ADVISORY ATTM.
THURSDAY THROUGH MONDAY...SURFACE HIGH PRESSURE AND A LARGE UPPER
RIDGE BUILD INTO THE REGION THROUGH THE END OF THE WORK WEEK. SOME
MODERATING TEMPERATURES IN THE 80S TO LOWER 90S BEGIN ON FRIDAY
AND CONTINUE THROUGH THE WEEKEND. WEAK SHORTWAVE CUTS ACROSS THE
STATE FRIDAY BUT WITH LIMITED MOISTURE AND FORCING...KEPT FORECAST
DRY FOR NOW. LATE IN THE WEEKEND...THE GFS AND ECMWF HINTING ON A
DECENT COLD FRONT AND UPPER LEVEL SHORTWAVE TO MOVE ACROSS THE
REGION LATE SATURDAY NIGHT INTO SUNDAY...THEN ANOTHER SHORTWAVE
THROUGH THE FORECAST AREA BY EARLY MONDAY.
&&
.AVIATION...28/06Z
ISSUED AT 1133 PM CDT MON JUL 27 2015
WARM FRONT ALOFT/SFC JUST TO WEST OF AREA THIS EVENING. MCS OVER
THE DAKOTAS/NEBRASKA WILL BEGIN TO EXPAND EAST/SOUTHEAST BETWEEN
09-13Z WITH AREA OF LIFT ACROSS NORTH CENTRAL IOWA BY 09-10Z AND A
GRADUAL EXPANSION FROM WEST CENTRAL/NORTH CENTRAL BY 10-12Z. HAVE
DELAYED ARRIVAL IN TAFS WITH UPDATED HRRR MODEL RUNS...SOUTHERN
SITES AT KDSM/KOTM SHOULD SEE LESS DURATION OF THUNDER BETWEEN
11-15Z THAN NORTH. AS MAIN COLD FRONT MOVES INTO THE AREA...
ANOTHER ROUND OF STORMS IS EXPECTED FROM 20-00Z LINGERING AFT
29/00Z OVER THE EAST. CONFIDENCE ON TIMING IS STILL MODEST...SO
HAVE KEPT VICINITY WORDING FOR NOW./REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
APPANOOSE-DAVIS-MAHASKA-MONROE-WAPELLO-WAYNE.
&&
$$
SHORT TERM...LEE
LONG TERM...PODRAZIK
AVIATION...REV
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1133 PM CDT MON JUL 27 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 416 PM CDT MON JUL 27 2015
FORECAST CONCERNS CONTINUE TO REVOLVE AROUND PRECIPITATION TRENDS.
ONGOING CONVECTIVE SYSTEM ACROSS CENTRAL IOWA THROUGHOUT THE DAY
TODAY WILL CONTINUE TO INFLUENCE CONVECTIVE TRENDS THROUGH THE
OVERNIGHT. HAVE KEPT POPS ACROSS THE AREA AS INSTABILITY WILL ALLOW
ONGOING PRECIPITATION TO CONTINUE TO PUSH EAST AND DROP SOUTHEAST.
IN ADDITION...CONCERNS FOR THE AFTERNOON REDEVELOPMENT TO THE WEST.
EXPECT BEST CHANCE TO BE FURTHER WEST INTO EASTERN IOWA ALONG
BOUNDARY...HOWEVER...THETA-E ADVECTION IS EXPECTED TO INCREASE
ACROSS WESTERN IOWA IN THE LATE AFTERNOON HOURS WHICH MAY SPARK
ADDITIONAL THUNDERSTORMS. CURRENT MESO ANALYSIS SHOWS CAPPING ACROSS
THIS AREA...AND HAVE TRENDED PRECIPITATION IN THIS AREA
DOWN...EXPECTING CAP TO HOLD.
NEXT FOCUS WILL BE PRECIPITATION TRENDS OVERNIGHT AS WAVE PUSHES
NORTH AHEAD OF BOUNDARY IN THE DAKOTAS. MODELS CONTINUE TO BE FASTER
WITH THIS SOLUTION...AND HAVE TRENDED THIS WAY. WILL BE SOME SEVERE
POTENTIAL WITH INSTABILITY REMAINING ACROSS THE AREA...THOUGH MAIN
CONCERN WILL BE WITH HEAVY RAIN POTENTIAL. PWAT VALUES NEAR 1.8
INCHES WITH GOOD MOISTURE TRANSPORT INTO THE REGION AND WARM CLOUD
DEPTHS. GIVEN ANTICIPATED BEST FORCING FURTHER NORTH OF IOWA...AND
QUICK PROGRESSION OF SYSTEM...WILL KEEP FLASH FLOOD HEADLINES OUT
FOR NOW.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 416 PM CDT MON JUL 27 2015
WE HAVE AN ACTIVE DAY LINED UP FOR TUESDAY...FOLLOWED BY A MUCH
MORE CLIMATOLOGICAL LEANING FCST PERIOD FOR THE REST OF THE LONG
TERM. MODELS IN GOOD AGREEMENT WITH PUSHING A COLD FRONT THROUGH
THE CWA FROM NW TO SE DURING TUESDAY. THREE MAJOR CONCERNS FOR
TUESDAY ARE STRONG TO SEVERE THUNDERSTORM POTENTIAL...HEAVY
RAINFALL POTENTIAL...AND NEAR HEADLINE HEAT INDEX VALUES.
FOR TUE HEAVY RAIN POTENTIAL...PWATS IN THE 2.1 TO 2.25 INCH
RANGE...ESPECIALLY OVER OUR NE CWA...ARE AROUND +3 TO +4 STD DEV.
NAM HAS PWATS APPROACHING 2.5 INCHES. IN TERMS OF MOISTURE AND
DWPTS...NAM ON THE HIGHER END AM LEANING TOWARDS IT SINCE IT IS
INITIALIZING WELL...PLUS THE TIME OF YEAR SUPPORTS MOIST. THE GFS IS
TOO DRY PER USUAL. PLENTY OF MOISTURE TRANSPORT VIA 30 KT LLJ AND
PLENTY OF SFC MOISTURE CONV WITH COLD FROPA. MIXING RATIOS ABOVE 8
G/KG PLUS 0-6 KM MUCAPES ABOVE 1500 J/KG WILL SUPPORT UPWARD
MOISTURE FLUX. TIME OF YEAR WOULD TYPICALLY BE A HUGE NEGATIVE FOR
FLOODING/FLASH FLOODING POTENTIAL. HOWEVER...SIGNIFICANT RAINFALL
OVER THE PAST 48 HOURS IN SOME LOCATIONS MAY LEAVE SOME AREAS FAIRLY
SATURATED.
FOR TUE SVR WX POTENTIAL...MAIN FOCUS WILL BE DAMAGING WINDS AND
SLIGHT TOR THREAT. WITH PWATS EXPECTED TO BE SO HIGH...UPDRAFTS WILL
LIKELY BE WATER LOADED...MAKING SEVERE HAIL PRODUCTION DIFFICULT.
BOTH GFS AND NAM PICK UP ON A POCKET OF 200 M2/S2 0 TO 3 KM HELICITY
WITH THE BOUNDARY TO OUR NORTH. LCL HEIGHTS WELL BELOW 1000M. IN
SHORT...NOT AN OUTBREAK ENVIRONMENT...BUT WORTH WATCHING.
FOR HEAT POTENTIAL...WENT WITHOUT ANY HEADLINES FOR NOW. MORNING
PRECIP/CLOUD COVER PLUS TIMING OF BOUNDARY ARRIVAL WILL LIKELY KEEP
TEMPS DOWN VERSUS FCST IN PREVIOUS FEW DAYS. REGARDLESS OF SFC
TEMPS...WILL STILL BE HOT AND HUMID WITH SFC DWPTS IN THE MID TO
UPPER 70S. HEAT INDEX VALUES WILL LIKELY TOP OUT IN THE UPPER 90S TO
LOW TRIPLE DIGITS IN AND SE OF THE DSM METRO. OVERNIGHT SHIFT MAY
NEED TO ISSUE ADVISORY IN OUR SE.
THE FRONT AND ANY LINGERING PRECIP SHOULD BE EAST OF OUR CWA BY
SUNRISE WEDNESDAY. A SFC ANTICYCLONE WILL HELP KEEP WEDNESDAY AND
THURSDAY QUIET AND DRY. 850 MB TEMPS DROP TO THE 14C TO 18C RANGE
WHICH WILL HELP PUSH TEMPS DOWN TO THE LOW 80S FOR WEDNESDAY.
FOR THE MIDDLE TO END OF THE WEEK...WE RETURN TO ZONAL FLOW. MID
LEVEL WINDS ARE ABOUT +1 TO +2 STD DEV FROM THE WEST. GIVEN ALL OF
THIS...LEFT BROAD-BRUSHED POPS THROUGH THE WEEKEND IN
ANTICIPATION OF SHORTWAVE TRAIN EXPECTED TO START CHUGGING AGAIN.
850MB TEMPS RETURN TO THE 19C TO 22C RANGE WHICH IS NEAR NORMAL
FOR THIS TIME OF YEAR. SUBSEQUENTLY...HAVE HIGHS CLOSE TO
CLIMO...IN THE MID TO UPPER 80S.
&&
.AVIATION...28/06Z
ISSUED AT 1133 PM CDT MON JUL 27 2015
WARM FRONT ALOFT/SFC JUST TO WEST OF AREA THIS EVENING. MCS OVER
THE DAKOTAS/NEBRASKA WILL BEGIN TO EXPAND EAST/SOUTHEAST BETWEEN
09-13Z WITH AREA OF LIFT ACROSS NORTH CENTRAL IOWA BY 09-10Z AND A
GRADUAL EXPANSION FROM WEST CENTRAL/NORTH CENTRAL BY 10-12Z. HAVE
DELAYED ARRIVAL IN TAFS WITH UPDATED HRRR MODEL RUNS...SOUTHERN
SITES AT KDSM/KOTM SHOULD SEE LESS DURATION OF THUNDER BETWEEN
11-15Z THAN NORTH. AS MAIN COLD FRONT MOVES INTO THE AREA...
ANOTHER ROUND OF STORMS IS EXPECTED FROM 20-00Z LINGERING AFT
29/00Z OVER THE EAST. CONFIDENCE ON TIMING IS STILL MODEST...SO
HAVE KEPT VICINITY WORDING FOR NOW./REV
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AWB/KA
LONG TERM...KOTENBERG
AVIATION...REV
AREA FORECAST DISCUSSION
NWS GOODLAND KS
558 PM MDT WED JUL 29 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 221 PM MDT WED JUL 29 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS WEST-
NORTHWEST FLOW ACROSS NORTHERN PLAINS WITH BROAD RIDGE ACROSS THE
SOUTHERN US AND TROUGH ACROSS THE NORTHERN GREAT LAKES. AT THE
SURFACE HIGH PRESSURE EXTEND FROM THE NORTHERN PLAINS ACROSS
WESTERLY KANSAS.
THIS AFTERNOON-TONIGHT...AXIS OF FAVORABLE LAPSE RATES (AROUND
7C/KM) IS IN THE PROCESS OF SHIFTING EAST WITH WEAK SHORTWAVE
TROUGH. AS THIS SHIFTS EAST CHANCE FOR SPRINKLES/LIGHT SHOWERS
COMES TO AN END (BY EARLY EVENING). LOW TEMPS TONIGHT WILL BE VERY
SIMILAR TO LAST NIGHT WITH NEAR SEASONAL VALUES AROUND 60F...AND
SOME COOLER LOCATIONS IN THE MID-UPPER 50S.
THURSDAY...H5 RIDGE BEINGS TO AMPLIFY ACROSS WESTERN US RESULTING
IN STRENGTHENING OF LEE TROUGH AND INCREASE IN WAA ACROSS EASTERN
COLORADO/FAR WESTERN KANSAS. TEMPS WILL APPROACH SEASONAL VALUES
IN THE UPPER 80S/NEAR 90 FOR MOST PARTS OF OUR CWA. STEEP MID
LEVEL LAPSE RATES AND 400-700 J/KG CAPE AXIS BEGINS TO BUILD BACK
OVER THE WESTER CWA...WHICH COULD RESULT IN THUNDERSTORM
DEVELOPMENT POSSIBLY AS EARLY AS MID MORNING THURSDAY. BEST
SURFACE CONVERGENCE IS WEST OF CWA...SO UNTIL WEAK ENERGY TOWARDS
THE CWA FROM THE SW DURING THE AFTERNOON WE PROBABLY WONT SEE ANY
ACTIVITY. BEST LIFT IS ALSO SOUTH OF OUR CWA...SO CONFIDENCE IS
LOW ON COVERAGE AT THIS POINT. BEST SIGNAL/CHANCES WILL BE ACROSS
THE WEST ROUGHLY ALONG KS/CO STATE LINE. WITH WEAK CAPE VALUES
SEVERE POTENTIAL IS VERY LOW DESPITE INCREASING EFFECTIVE SHEER
LATE THURSDAY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 145 PM MDT WED JUL 29 2015
THE LONG TERM FORECAST PERIOD WILL BE DOMINATED BY AN UPPER LEVEL
HIGH PRESSURE SYSTEM POSITIONED OVER THE SOUTH CENTRAL CONUS...WHICH
WILL BRING THE RETURN OF NEAR NORMAL TEMPERATURES IN THE LOWER TO
MID 90S ON FRIDAY. THE UPPER LEVEL RIDGE WILL CONTINUE TO AMPLIFY
OVER THE WESTERN THIRD OF THE CONUS ON FRIDAY...WHICH WILL BRING
MOSTLY DRY CONDITIONS. HOWEVER...A FRONTAL BOUNDARY WILL BE
POSITIONED OVER THE SOUTH/SOUTHWEST CORNER OF THE FORECAST AREA
WHICH WILL BRING SOME CHANCES FOR SOME DEVELOPING SHOWERS AND
THUNDERSTORMS FOR FRIDAY THROUGH SATURDAY. SEVERE INDICATORS AT
THIS TIME LOOK MARGINAL AT BEST...SO SEVERE WEATHER IS NOT
ANTICIPATED AT THIS TIME.
AS UPPER LEVEL RIDGE AMPLIFIES OVER THE WEEKEND WITH A LACK OF A
SURFACE FORCING MECHANISM...SO EXPECTING DRY WEATHER FOR THE REST OF
THE WEEKEND SATURDAY NIGHT THROUGH SUNDAY. WARM SURFACE SOUTHERLY
FLOW WILL CONTINUE TO BRING INCREASED MOISTURE WITH DEW POINTS IN
THE MID 60S AND TEMPERATURES IN THE UPPER 80S TO LOWER 90S.
THE NEXT CHANCES FOR PRECIPITATION WILL BE TUESDAY AS AN UPPER LEVEL
SHORTWAVE TROUGH APPROACHES THE CENTRAL HIGH PLAINS REGION. MODEL
FORECASTS DIFFER AS TO THE LOCATION AND TIMING OF THE FEATURE...WITH
THE ECMWF BRINGING THE DISTURBANCE IN THE FASTEST STARTING TUESDAY.
AT THIS POINT...NOT VERY CONFIDENT THAT SHOWERS AND STORMS WILL
DEVELOP CONSIDERING GFS/CANADIAN/DGEX MODELS ALL INDICATE THE RIDGE
MAINTAINING STRENGTH OVER THE REGION. TO STAY WITHIN FORECAST
COLLABORATION THRESHOLDS...KEPT CHANCES FOR PRECIPITATION IN THE
FORECAST...ESPECIALLY CONSIDERING THAT THE ECMWF TENDS TO LATCH ON
TO FORECAST PATTERNS SOONER THAN THE OTHER MODELS IN THE LONG TERM
PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 549 PM MDT WED JUL 29 2015
VFR CONDITIONS WILL PREVAIL THROUGH MUCH OF THE FORECAST PERIOD.
A FEW SCATTERED SHOWERS OR THUNDERSTORMS COULD BE IN THE VICINITY
OF KGLD STARTING AROUND 18Z THURSDAY WITH KMCK LIKELY NOT SEEING
ANY SHOWER ACTIVITY THROUGH THE FORECAST PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...TL
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1021 PM EDT WED JUL 29 2015
.UPDATE...
ISSUED AT 1020 PM EDT WED JUL 29 2015
THE COLD POOL ASSOCIATED WITH THE LINE OF STORMS HAS CONTINUED TO
CONSOLIDATE TO THE WEST AND SOUTH OF OUR AREA. ONLY A FEW OF OUR
SOUTHWEST COUNTIES WILL SEE LIKELY RAINS OVER THE NEXT HOUR OR SO.
THE REMNANT STRATIFORM RAINFALL ACROSS CENTRAL KENTUCKY IS NOT
MOVING MUCH...AND WILL GRADUALLY WEAKEN...MAINLY IN PLACE. THE
LAST FEW RUNS OF THE HRRR HAS GENERALLY CAUGHT ON TO THE ONGOING
CONVECTIVE TRENDS. AS SUCH...IT APPEARS THAT THERE MAY NOT BE MUCH
IN THE WAY OF ACTIVITY UNTIL THE ACTUAL FRONTAL BOUNDARY MOVES
SOUTHEAST ACROSS THE AREA DEEPER INTO THE OVERNIGHT HOURS...WHEN A
SLIGHT UPTICK IN ACTIVITY MAY OCCUR. WILL THEREFORE HANG ONTO
SLIGHT TO CHANCE POPS. ALSO ADJUSTED THE LOWS UP A TOUCH...AS THE
PUSH BEHIND THE FRONT IS NOT VERY STRONG. THE BEST CHANCE OF
SEEING SOME UPPER 60 DEGREE READINGS LOOKS TO BE ALONG AND NORTH
OF I-64. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 813 PM EDT WED JUL 29 2015
THE LATEST RADAR MOSAIC SHOWS A CONVECTIVE LINE ACROSS CENTRAL
AND WESTERN KENTUCKY. NEW CELLS HAD BEEN MORE LIVELY A BIT FURTHER
NORTHEAST EARLIER...BUT SOME PRECURSORY STORMS TAPPED INTO THE
BETTER AVAILABLE AIR MASS...AND NOW THERE IS GENERALLY A WEAKENING
TREND ON THE EASTERN FLANK OF THE LINE...WITH BETTER COLD POOL AND
ASSOCIATED NEW DEVELOPMENT ALIGNING MORE TOWARDS THE SOUTH...WHERE
BETTER INSTABILITY REMAINS. STILL...THINK THAT SOME DEBRIS CELLS
WILL MAKE IT INTO THE WEST IN THE NEXT 1 TO 2 HOURS...AND HAVE
UPPED THE POPS TO HIGH CHANCE TO LIKELY FOR THOSE LOCATIONS. AS WE
LOSE HEATING...EXPECT AN OVERALL GRADUAL DIMINISHMENT...HOWEVER
WILL STILL HAVE TO KEEP AN EYE ON HEAVY RAINERS...GIVEN THE HIGH
PWATS AND THE POTENTIAL FOR TRAINING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 343 PM EDT WED JUL 29 2015
AS OF MID AFTERNOON A MID LEVEL RIDGE WAS CENTERED OVER THE
SOUTHERN PLAINS REGION...WITH A CLOSED MID LEVEL LOW OVER
NORTHWESTERN ONTARIO AND THE ASSOCIATED TROUGH SOUTH INTO THE MS
VALLEY REGION. AT THE SFC...AN AREA OF LOW PRESSURE WAS CENTERED
OVER ONTARIO WITH A COLD FRONT SOUTH INTO THE CENTRAL GREAT LAKES
AND THEN SOUTHWEST INTO THE MID MS VALLEY AND CENTRAL PLAINS.
CONVECTION HAS DEVELOPED ALONG OR IN ADVANCE OF THIS FRONT OVER OH
AND IN SOUTHWEST INTO WESTERN KY. ADDITIONAL CONVECTION HAS
DEVELOPED NEAR A MOISTURE GRADIENT EVIDENT IN PW FROM NORTHERN KY
SOUTH INTO CENTRAL KY. THIS CONVECTION HAS BEEN GENERALLY SLOW
MOVING WITH HEAVY RAINFALL RATES. AREAWIDE...A WARM AND MOIST
AIRMASS IS IN PLACE WITH TEMPERATURES IN THE MID TO UPPER 80S TO
NEAR 90 AND DEWPOINTS IN THE UPPER 60S TO MID 70S.
THE CLOSED MID LEVEL LOW WILL TRACK TO HUDSON BAY WITH THE
TRAILING SHORTWAVE TROUGH MOVING THROUGH THE GREAT LAKES AND MID
AND UPPER OH VALLEY REGION TONIGHT. THIS SHORTWAVE TROUGH WILL
MOVE INTO THE NORTHEASTERN CONUS THROUGH THURSDAY. AT THE SAME
TIME...THE MID LEVEL RIDGE WILL RETROGRADE AND AMPLIFY AND BECOME
CENTERED OVER THE SOUTHERN ROCKIES OR FOUR CORNERS REGION. THIS
WILL PUT THE REGION IN NW FLOW ALOFT LATE IN THE PERIOD. AT THE
SFC...THE COLD FRONT WILL CROSS THE REGION BY LATE TONIGHT OR
EARLY ON THURSDAY. THEN...HIGH PRESSURE WILL BUILD IN BEHIND THE
DEPARTING COLD FRONT AND USHER IN SLIGHTLY COLDER...BUT MORE
NOTICEABLY DRIER AIR INTO THE REGION.
RATHER MEAGER MID LEVEL FORCING AND NON OPTIMAL TIMING OF THE
FROPA DURING THE LATE EVENING INTO OVERNIGHT HOURS SHOULD LIMIT
CONVECTION THIS EVENING AND TONIGHT TO ISOLATED TO SCATTERED
COVERAGE. IT STILL APPEARS THAT THERE SHOULD BE A PEAK IN COVERAGE
OVER THE NEXT 3 HOURS OR SO...AND THEN MORE ORGANIZED CONVECTION
WITH A POSSIBLE BROKEN LINE OR LINE SEGMENTS OF SHOWERS AND
THUNDERSTORMS AS THE COLD FRONT MOVES THROUGH. WITH RELATIVELY
SLOW STORM MOTIONS EXPECTED DUE TO WEAK FLOW ALOFT AND A MOIST
AIRMASS IN PLACE...ANY STRONGER THUNDERSTORMS COULD PRODUCE VERY
HEAVY RAINFALL RATES AND OUTFLOW WIND GUSTS IN EXCESS OF 30 MPH
WILL BE POSSIBLE THIS EVENING SIMILAR TO A GUST OBSERVED OVER
CENTRAL KY EARLIER THIS AFTERNOON.
A SHOWER OR POSSIBLY A THUNDERSTORM COULD LINGER EARLY ON
THU...OVER THE SOUTHEASTERN CWA...PARTICULARLY NEAR THE VA BORDER.
OTHERWISE... AS DRIER AIR MOVES IN THROUGHOUT THE COLUMN SKIES
SHOULD BECOME MOSTLY SUNNY IN MOST LOCATIONS ON THU AFTERNOON.
WITH THE HIGH BUILDING IN...CLEAR SKIES AND LIGHT WINDS SHOULD SET
THE STAGE FOR VALLEY FOG FORMATION LATE IN THE PERIOD. ENOUGH
DRIER AIR SHOULD WORK IN FOR SOME OF THE NORMALLY COLDER LOCATIONS
ALONG...OR NORTH OF THE MTN PARKWAY COULD TOUCH THE UPPER 50S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 256 PM EDT WED JUL 29 2015
THE EXTENDED PERIOD LOOKS FAIRLY BENIGN AS SURFACE HIGH PRESSURE
TAKES CONTROL OF THE REGION THROUGH EARLY NEXT WEEK. THIS WILL
ALLOW FOR SLIGHTLY COOLER AND DRIER AIR TO FILTER INTO THE REGION
FOR THE WEEKEND. HIGHS FRIDAY THROUGH SUNDAY WILL BE IN THE LOW TO
MID 80S...BUT DEWPOINTS IN THE UPPER 50S AND LOW 60S WILL MAKE
THOSE READINGS FEEL MUCH MORE PLEASANT THAN THEY HAVE RECENTLY.
A WEAK AND MOISTURE STARVED FRONT APPROACHES THE REGION SATURDAY
MORNING...WITH BOTH THE GFS AND ECMWF SHOWING THE PRECIP FALLING
APART BEFORE IT REACHES THE FORECAST AREA. THIS IS LIKELY DUE TO
THE DRY AIR/RIDGING AT THE SURFACE. THERE IS SOME MID LEVEL
MOISTURE AND WEAK ENERGY WITH THE FRONT AS IT PASSES TO OUR NORTH
SO HAVE KEPT A SLIGHT CHANCE OF AN ISOLATED SHOWER IN THE FAR
NORTHERN COUNTIES. BUT DO NOT EXPECT MUCH MORE THAN AN INCREASE IN
SOME MID LEVEL CLOUDS ON SATURDAY FOR MOST AREAS.
SHOWER CHANCES RETURN TO THE REGION BY TUESDAY AS THE UPPER LEVEL
PATTERN BECOMES MORE ACTIVE. MODELS INDICATE THAT SEVERAL UPPER
LEVEL IMPULSES EMBEDDED IN THE NW FLOW WILL MOVE ACROSS EASTERN
KENTUCKY THROUGH THE END OF THE FORECAST PERIOD BRINGING INCREASED
SHOWER AND THUNDERSTORM CHANCES THROUGH THE END OF THE WORK WEEK.
TEMPERATURES (AND HUMIDITY) WILL INCREASE BACK INTO THE UPPER 80S
BY THE END OF THE PERIOD...WITH HEAT INDICES LIKELY SURPASSING THE
90 DEGREE MARK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 813 PM EDT WED JUL 29 2015
CONVECTIVE LINE WILL GRADUALLY MAKE IT IN FROM THE WEST. HAVE
SYM...LOZ AND SME SEEING THE BEST CHANCE OF SUSTAINED CONVECTION
AND MVFR CONDITIONS BETWEEN 01 AND 02Z...WITH SOME TEMPORARY IFR
CONDITIONS POSSIBLE AT SME AND LOZ BETWEEN 02 AND 03Z. HAVE
ALLOWED MORE TEMPORARY TS AND MVFR CONDITIONS AT JKL...WITH A
GENERAL VCTS AT SJS...WHERE THERE IS MORE UNCERTAINTY WHETHER MORE
ORGANIZED STORMS CAN MAKE IT THAT FAR EAST. A COLD FRONT WILL
EVENTUALLY PUSH THROUGH THE AREA OVERNIGHT...WITH WINDS SHIFTING
TO THE NORTHWEST. MVFR STRATOCU AND A FEW SHOWERS WILL LINGER
THROUGH THURSDAY MORNING...BEFORE DISSIPATING THEREAFTER WITH A
RETURN TO VFR.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JP
LONG TERM...JVM
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
545 PM EDT Tue Jul 28 2015
...Forecast Update...
Issued at 545 PM EDT Tue Jul 28 2015
Did a grid update earlier this hour to account for current radar
trends. Latest HRRR finally getting a handle on precip this
afternoon, and it shows this precip decaying with sunset. Previous
runs had the cells over central Illinois decaying immediately after
model initialization, which has not occurred yet. Latest CIMSS
NearCast does show the central part of our county warning area being
a less likely place for storm development, and despite stronger
outflows moving through that region, we only are seeing weak storms.
Latest AMDAR data from a flight into SDF confirms this thinking,
with a fairly strong cap above 600 mb that is limiting how tall the
storms near SDF are getting.
Despite that cap, the presence of these boundaries as well as a
muggy airmass should keep non-severe storms forming over the next
few hours until we can get the sun to set. Latest NAM still trying
to show a wave of decaying storms coming in to our western forecast
area toward daybreak. These would be from the cells now over Iowa as
they round the top of the ridge over the mid MS valley. Made no
changes to the daybreak period for now.
.SHORT TERM (Now through Wednesday Night)...
Issued at 325 PM EDT Tue Jul 28 2015
Scattered storms were ongoing across the area as of 19Z. Some
storms were strong with lots of lightning, torrential rainfall, and
gusty winds up to around 40 mph. Expect convection to continue
through the evening hours as an upper level shortwave dropping SE
out of IL keeps storms going or even enhances development this
evening. With ample instability in place as well as DCAPE, high
precipitable water values, and weak boundaries for storms to train
along, a strong wind threat and localized flooding threat will
continue through the evening hours. Storms should diminish through
the late evening hours with the area becoming completely dry after
midnight. Expect low temps in the low to mid 70s with some patchy
fog/haze developing after midnight as it has done the past few
mornings.
For Wednesday, we`ll start the day with a dying complex of storms
entering areas west of I-65. This morning batch should fizzle out
or become just isld showers by mid morning. Some breaks in the
clouds are expected during the morning and early afternoon hours
allowing some instability to build. A cold front will approach the
area Wed afternoon causing more convection to fire. Although
morning clouds/precip may inhibit the environment somewhat and the
front is pretty weak, we should still have enough forcing and
instability to produce strong to marginally severe storms with
strong winds, small hail, and torrential rainfall. Storms should
persist through the evening before diminishing by late evening with
the cold front passage. Highs for Wed should range through the
upper 80s to lower 90s with heat index values in the lower 100s
mainly west of I-65. The good news is any precip should provide
relief from the heat tomorrow and there is a good chance for precip
to occur 40-50%. Wed night low temps should range through upper
60s/lower 70s.
.LONG TERM (Thursday through Tuesday)...
Issued at 245 PM EDT Tue Jul 28 2015
The main forecast concern in the long term is temperatures as much
of the extended forecast looks dry across the lower Ohio Valley. The
start of the period /Thursday morning/ will feature a cold front
bisecting the forecast area. A pool of high moisture along and ahead
of the front combined with weak lift will support the chance of
showers/storms during the morning hours across south-central
Kentucky. The front then quickly drops into TN by 18z and in its
wake, much drier and more pleasant conditions will build into the
region.
Plan on low humidity and more pleasant summer conditions Thursday
afternoon through Friday as highs top out right around normal /mid
to upper 80s/ and overnight lows will be in the low to mid 60s.
Outside of scattered afternoon cumulus, skies look to be mostly
sunny to sunny.
A weak front approaches from the northwest on Saturday but will
likely wash out before making it to the Ohio River. Humidity will
slowly increase this weekend as dewpoints creep back up into the
mid/upper 60s. Look for afternoon highs to gradually warm as well,
approaching 90 degrees by Sunday.
Going into next week, will continue to advertise a dry forecast as
approaching fronts wash out or stall to the northwest. Some signals
that a stronger front may make a push through the area mid to late
week but model uncertainty is high.
&&
.AVIATION (18Z TAF Update)...
Updated 125 PM EDT Tue Jul 28 2015
Isld to scattered t-storms will continue to develop over the region
this afternoon/evening as upper level shortwaves on the NE side of
an upper ridge continue to spark convection in a moist, unstable
atmosphere. Because coverage of storms is not great and confidence
is low if one will hit a TAF site, left VCTS in the TAFs through
this evening. Will need to add a tempo if a cell develops near the
TAF sites though. We should see a break in activity tonight with
winds going calm or light and vrb. Some light br or hz is expected
at all TAF sites. Winds will be WNW mainly staying under 7kts for
tomorrow with an approaching cold front bringing another chance for
shower/storms.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........RJS
Short Term.....AMS
Long Term......ZBT
Aviation.......AMS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
936 AM EDT TUE JUL 28 2015
.SYNOPSIS...
A FRONTAL BOUNDARY WILL CROSS THE AREA TODAY. HIGH PRESSURE AND
DRIER AIR WILL BUILD IN FOR WEDNESDAY FOLLOWED BY ANOTHER FRONTAL
SYSTEM FOR THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
935 AM UPDATE...
ILL-DEFINED SFC TROF LOOKS TO BE LOCATED ALONG THE GULF OF ST.
LAWRENCE AT THIS TIME BASED ON LWR DWPTS ALONG WITH 3 HR PRESSURE
CHG GRADIENT. EXPECT THIS BNDRY WL SLIP SOUTH THRU THE COURSE OF
THE DAY LKLY ENTERING NRN MAINE BY NOON, EFFECTIVELY CUTTING OFF
ANY THREAT FOR STORMS OVR THE FAR NORTH. DEPENDING ON HOW FAR THIS
BNDRY CAN SLIP WL DETERMINE WHERE STORMS MAY DVLP.
PRIOR RUN OF HRRR SHOWED ESSENTIALLY NIL FOR CONVECTION TDA WHILE
THE LATEST RUN IS NOW SHOWING ISOLD ECHOES DVLPNG DOWNEAST AFT 17Z
THIS AFTN, WHICH THE LATEST RAP IS NOW COMING ON BOARD WITH.
LATEST MESOANALYSIS PAGE IS SHOWING 500 J ACRS CNTRL SXNS OF CWA
WITH CIN OVR THE CROWN AND ALSO DOWNEAST IN WAKE OF STORMS AND
LINGERING CLD CVR.
STILL EXPECTING MOST OF CONVECTION TO EXIST MAINLY SOUTH OF A
BANGOR-DANFORTH LINE THIS AFTN THO THIS WL DEPEND ON HOW FAST
BNDRY CAN SLIP THRU. PROGGED 0-6KM BULK SHEAR VALUES WL BE
MARGINAL FOR SVR STORMS THIS AFTN WITH CAPES APPCHG 1000 J/KG IN
DOWNEAST AREAS. TWEAKED POP, WX AND SKY GRIDS WITH THIS UPDATE
WITH JUST ADJUSTMENTS TO HRLY T/TD VALUES AT THIS TIME.
PREV DISCUSSION BLO...
A SURFACE TROUGH ACCOMPANIED BY AN UPPER LEVEL SYSTEM CURRENTLY
MOVING ACROSS THE AREA WILL CONTINUE TO MOVE TO THE EAST DURING
THE DAY TODAY. EXPECT FOCUS OF THUNDERSTORMS THIS AFTERNOON WILL
BE FROM CENTRAL SOUTHWARD TO INTERIOR DOWNEAST WITH COASTAL AREAS
REMAINING TOO STABLE. WILL INCLUDE WORDING FOR SMALL HAIL AND
GUSTY WIND IN HIGHEST PROBABILITY AREAS. WILL BLEND THE NAM AND
GFS FOR POPS... QPF AND SKY CONDITIONS. THE MAXIMUM TEMPERATURE
FROM THE BIAS CORRECTED CONSENSUS ALL. THE MINIMUM TEMPERATURE
FROM THE SUPER BLEND BASED ON LATEST VERIFICATION.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
THE MAIN FOCUS FOR THIS TERM WILL BE ON THURSDAY W/THE FRONTAL
BOUNDARY.
FOR WEDNESDAY, THE FRONTAL BOUNDARY WILL STALL RIGHT ACROSS THE
DOWNEAST REGION W/THE UPPER LOW DROPPING S ACROSS WESTERN NEW
BRUNSWICK. THIS WILL MEAN A FEW SHOWERS ACROSS EASTERN WASHINGTON
DOWN ACROSS HANCOCK COUNTIES IN THE AFTERNOON(20-30%). THE MODEL
SOUNDINGS DO SUPPORT SOME INSTABILITY W/SB CAPES AROUND 300 JOULES
AND LIS DOWN TO -2. MID LEVEL LAPSE RATES ARE FORECAST TO BE
AROUND 6.0 C/KM. NOT TOO IMPRESSIVE. DECIDED TO STAY CLOSE TO TO
THE DAYCREW`S THINKING OF POSSIBLE TSTMS RIGHT ALONG THE BOUNDARY
AS THERE WILL BE SOME LLVL CONVERGENCE AND POSSIBLE HEATING. NOT
EXPECTING ANY SEVERE TSTMS. FURTHER N AND W, MUCH DRIER AND SUNNY.
DAYTIME TEMPERATURES ARE EXPECTED TO BE AOA NORMAL READINGS FOR
LATE JULY. CLEARING TO TAKE PLACE WEDNESDAY NIGHT W/SOME FOG
DEVELOPING. OVERNIGHT LOWS FORECAST TO BE IN THE UPPER 50S NORTH
AND WEST TO AROUND 60 CENTRAL AND DOWNEAST.
FOR THURSDAY, ANOTHER FRONTAL BOUNDARY IS FORECAST TO MOVE ACROSS
THE STATE LATER THURSDAY INTO THURSDAY NIGHT. THE GFS/NAM AND
ECMWF ALL SHOW DECENT LLVL WARMING W/SOME UPPER DIFFLUENCE OUT
AHEAD OF THE SURFACE FRONT. SURFACE HEATING LOOKS TO BE A GOOD BET
AS THE FRONT IS SLATED TO ARRIVE LATER IN THE DAY. SOME OF THE
INSTABILITY PARAMETERS INCLUDING THE GFS ARE THERE FOR POSSIBLE
STRONG TO POSSIBLE SEVERE TSTMS LATER IN THE AFTERNOON INTO THE
EVENING MAINLY FOR WESTERN MAINE. THESE PARAMETERS INCLUDE:
LOW/MID LEVEL LAPSE RATES HITTING 6.5 C/KM, SB/MU CAPES 1500+
JOULES W/LIS DOWN TO AROUND -5. INCREASING HUMIDITY SURFACE
DEWPOINTS ARE PROGGED TO INCREASE INTO THE RANGE OF 65 TO 70.
FREEZING LEVELS/WBZS AROUND 11.5K FT TO SUPPORT HAIL AND SHEAR IS
THERE AS WELL TO SUPPORT WIND POTENTIAL. ATTM, IT LOOKS LIKE A SSE
WIND WILL KEEP LLVLS STABLE ACROSS CENTRAL AND EASTERN AREAS TO
ALLEVIATE A SEVERE THREAT. THE DAY 3 CONVECTIVE OUTLOOK FROM SPC
HAS THE WESTERN SECTIONS IN A MARGINAL RISK FOR SOME STORMS TO GO
SEVERE. ATTM, WILL KEEP GENERAL WORDING FOR TSTMS IN THE FORECAST
AND LET THE DAYCREW ASSESS THIS FURTHER W/THE LATEST GUIDANCE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE ACTIVE PATTERN LOOKS LIKE IT WILL CONTINUE INTO THE WEEKEND.
FOR THURSDAY NIGHT, THAT FRONTAL SYSTEM MENTIONED IN THE SHORT
TERM SECTION IS EXPECTED TO MOVE TO THE E OVERNIGHT AND INTO WESTERN
NEW BRUNSWICK BY FRIDAY MORNING. SHOWERS/TSTMS WILL MOVE TO THE E
W/THE FRONT AND WEAKEN AS THE BEST FORCING SHIFTS E AND
INSTABILITY WEAKENS. USED A CONSENSUS OF THE GFS AND ECMWF FOR
PLACEMENT OF THE FRONT AND HAVE HIGHEST CHANCES OF SHOWERS AND
TSTMS(60%) ACROSS NORTHERN AND EASTERN SECTIONS EARLY IN THE NIGHT
AND THEN DROP CHANCES DOWN TO 30-40% AS ACTIVITY WEAKENS.
AN UPPER LEVEL IMPULSE IS FORECAST TO MOVE ACROSS THE REGION ON
FRIDAY W/THE BEST SUPPORT FOR ANY PRECIP ACROSS NORTHERN AND
WESTERN MAINE. THE GFS AND ECMWF BOTH SHOW LLVLS WARMING ON
FRIDAY W/SOME SLIGHT COOLING ALOFT. THERE APPEARS TO BE SOME
INSTABILITY AND SHEAR TO SUPPORT THE MENTION OF TSTMS(ISOLATED)
ACROSS THE NORTH AND WEST FRIDAY AFTERNOON. ATTM, KEPT CHANCES AT
30% AS BEST MOISTURE RESIDES AROUND THE 850MB LEVEL. SHOWERS WILL
END FRIDAY NIGHT W/THE LOSS OF DIURNAL HEATING AND BEST FORCING
LIFTS OUT OF THE AREA.
ANOTHER FRONTAL BOUNDARY IS SLATED TO MOVE INTO THE REGION ON
SATURDAY W/AN UPPER TROF MOVING INTO THE REGION AT THE TIME OF
PEAK HEATING. ONCE AGAIN, ATMOSPHERE LOOKS LIKE IT WILL
DESTABILIZE TO SUPPORT POSSIBLE TSTMS SATURDAY AFTERNOON INTO THE
EVENING. DECIDED ON 40% POPS FOR SHOWERS/TSTMS INTO THE EVENING
AND THEN THINGS EXPECTED TO CLEAR LATER SATURDAY NIGHT INTO SUNDAY
W/A MORE SUMMER-LIKE PATTERN.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: PRIMARILY EXPECT IFR/MVFR CONDITIONS THIS MORNING
IMPROVING IN ALL AREAS TO VFR CONDITIONS THIS AFTERNOON AND
TONIGHT.
SHORT TERM: MVFR/IFR FOR KBGR AND KBHB EARLY WEDNESDAY MORNING.
OTHERWISE, VFR TO COVER IT INTO EARLY THURSDAY. THE EXCEPTION TO
THIS WILL BE KBHB AS A SSE FLOW COULD LEAD TO MVFR/IFR IN LOW CIGS
AND FOG AHEAD OF AN APPROACHING FRONTAL BOUNDARY. SHRA/TSRA
EXPECTED LATER THURSDAY AFTERNOON INTO THE EVENING LEADING TO
CONDITIONS DROPPING TO MVFR AND POSSIBLY IFR.
&&
.MARINE...
NEAR TERM: HAVE USED THE NAM12 FOR SUSTAINED WINDS. FOR WAVES:
CURRENTLY WITH WINDS UNDER 5 KNOTS PRIMARY WAVE SYSTEM IS FROM
INCOMING SOUTHEASTERLY SWELL 2 FEET/11 SECONDS. WITH WIND SPEEDS
EXPECTED TO STAY LIGHT THROUGH TONIGHT EXPECT THIS CURRENT LONG
PERIOD WAVE SYSTEM TO DOMINATE . WILL USE THE NEAR SHORE WAVE
MODEL TO POPULATE GRIDS.
SHORT TERM: NO EXPECTING ANY SCA HEADLINES THIS TERM. FOG AND
POSSIBLE TSTMS COULD HAMPER NAVIGATION ESPECIALLY EARLY WEDNESDAY
AND AGAIN THURSDAY NIGHT W/FRONTAL PASSAGES. WINDS DURING THIS
TIMEFRAME ARE FORECAST TO AVERAGE AROUND 10 KTS EXCEPT HIGHER IN
ANY TSTMS. SEAS TO AVERAGE AROUND 3 FT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FARRAR/MIGNONE
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...FARRAR/MIGNONE/HEWITT
MARINE...FARRAR/MIGNONE/HEWITT
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1000 PM EDT WED JUL 29 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA LATE THURSDAY. HIGH PRESSURE WILL
BUILD FOR THE WEEKEND AND HOLD THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
PCPN CVRG HAS BEEN MUCH SPOTTIER...AND LIGHTER...THAN THIS TIME
YDA. WARM LYR BTWN H6-4 ON 00Z LWX RAOB LKLY THE REASON WHY. RDR
TRENDS SEEM TO HV BEEN CAPTURED BY THE HRRR QUITE WELL. STORMS E
OF THE BLURDG HV DSPTD...W/ ONLY A FEW CELLS IN THE PTMC
HIGHLANDS. IF LTST CYCLE OUTPUT VERIFIES...EVEN THIS ACTIVITY WL
ERODE BEFORE MIDNGT...W/ NOT MUCH GOING ON TIL NEW CELLS APPROACH
THE APLCNS PREDAWN. HV ADAPTED GRIDS TWD THIS DIRECTION...BUT HV
HELD ONTO LOW POPS IN THE MTNS. THAT CAN BE REEVALUATED.
NOT NEARLY AS MUCH WET GRND AS PAST CPL NGTS. HWVR A FAIR AMT OF
CLR SKIES AND DEWPTS IN THE LWR-MID 70S SUGGESTS THERE WL ONCE AGN
BE POTL FOR FOG DVLPMNT. HV KEPT IT PATCHY AND NOT DENSE DUE TO
REASONS MENTIONED ABV...SITUATED ALONG/W OF BLURDG AS WELL AS
ACRS NRN MD.
CDFNT CURRENTLY MOVING THROUGH THE MIDWEST WILL ENTER THE FCST
AREA AROUND 18Z THU AND SHOULD CLEAR THE FCST AREA BY 03Z FRI.
FRONT WILL BE LOSING MUCH OF ITS PUNCH BUT IT APPEARS THERE COULD
BE A QUICK BAND OF -SHRA/TSRA RIGHT ALONG OR JUST BEHIND THE
FRONT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
12Z MODEL SUITE HAS THE COLD FRONT PLACED JUST SOUTHEAST OF THE
CWA BY 12Z FRIDAY. ANY LINGERING PCPN WITH THE FRONT SHOULD REMAIN
TO THE SOUTH AS THE FRONTAL BOUNDARY STALLS AND EVENTUALLY
DISSIPATES OVER THE WEEKEND. SFC HIGH PRESSURE BUILDS IN FROM THE
WEST IN THE WAKE. THE REGION WILL REMAIN AT THE SOUTHERN FRINGE OF
BROAD CLOSED LOW OVER CANADA...WITH THE SHORTWAVE ENERGY ROUNDING
THE LOW REMAINING WELL TO THE NORTH. AS SUCH...EXPECTING DRY WX
FRI AND FRI NIGHT. 12Z GFS SUGGESTING LIGHT PCPN OVER NORTHEASTERN
AREAS OF THE CWA SAT AFTN WITH A SHORTWAVE JUST TO THE NORTH. WILL
KEEP THINGS DRY FOR NOW THOUGH DURING THIS TIME WITH LACK OF SFC
FORCING CURRENTLY NOTED.
QUICK SHOT OF CAA IN THE WAKE OF THE FRONT ON FRIDAY DROP 850MB
TEMPS TO AROUND 15 DEGREES CELSIUS...RESULTING IN HIGHS GENERALLY IN
THE 80S. THE COOLER AIRMASS WILL BE SHORT LIVED AS THE HIGH BUILDS
IN...WITH 850MB TEMPS REBOUNDING BACK TO NEAR 20 DEGREES CELSIUS BY
SAT AFTN. LOWS FRIDAY NEAR NORMAL...WITH HIGHS NEARING 90 ON
SATURDAY. DEW PTS IN THE 60S SAT SHOULD KEEP HEAT INDICES WELL BELOW
ADVISORY LVLS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
QUIET WEATHER PATTERN FOR SUN INTO MON WITH HIGH PRESS DOMINATING
CONDITIONS BEHIND A COLD FRONT. THE FRONT LINGERS OFF THE DELMARVA
COAST AS IT WEAKENS... THEREFORE CANNOT RULE OUT SOME SHOWERS TO
THE SE AND E OF OUR CWA. SHORTWAVE TROUGH COULD BRING SOME AFTN
SHOWERS ON MON AND TUE... BUT CONFIDENCE WITH IT IS LOW ATTM... SO
HAVE KEPT LOW POPS. ANOTHER FRONT APPROACHES ON WED INCREASING THE
CHANCE OF SHOWERS AND TSTMS FOR THIS DAY. TEMPS WILL NEAR NORMAL
SUN AND GRADUALLY INCREASING INTO HE LOW 90S FOR WED.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
VFR CONDS ACRS THE TERMINALS ATTM. SETUP SEEMS FVRBL FOR FOG
DVLPMNT ONCE AGN BTWN MIDNGT-DAWN. HWVR NOT AS MUCH WET GRND AS
PAST NGTS...WHICH IS COUNTERED BY HIER DEWPTS/LLVL HUMIDITY.
UNSURE EXACTLY HOW THESE TWO FACTORS WL BALANCE EACH OTHER. HV
OPTED TO KEEP PROLONGED MVFR CONDS OVNGT AT MRB...IFR AT CHO
WHERE SHRA WAS RECVD...AND ONLY BRIEF MVFR AT SUNRISE IAD/MTN. DO
NOT HV HIGH CONFIDENCE ATTM. CUD SEE FLGT CONDS WORSE THAN FCST
BUT WAS HESITANT ON OFFERING UP PROLONGED RESTRICTIONS.
FLGT RESTRICTIONS FOR THE MRNG PUSH WL ERODE BY MID MRNG. A CDFNT
WL CROSS THE TERMINALS DURING THE AFTN...AFFECTING THAT PUSH AS
WELL. SCT-NRMS SHRA/TSRA WL BE FOUND ALONG/AHD OF THE FNT. THINK
THERE WL BE SOME DIURNAL STRENGTHENING...AND AM CARRYING VCTS FOR
DC/BALT TERMINALS AS A RESULT. WUD NOT COMPLETELY RULE OUT IMPACT
AT CHO/MRB BUT PROBABILITY IS LESS. IN THE EVENT OF A DIRECT HIT
BRIEF AOB IFR CAN BE ANTICIPATED. TIMING/SPATIAL UNCERTANTIES
PRECLUDE CARRYING ANY SPECIFIC MENTION ATTM. WSHFT NEAR 18Z AT
MRB...SPREADING EAST TO 21-22Z DCA/BWI.
VFR CONDITIONS FRIDAY AND SATURDAY. WINDS GENERALLY 10 KTS OR
LESS...SHIFTING FROM THE NW FRIDAY TO A WESTERLY FLOW SAT.
&&
.MARINE...
SLY WNDS SUSTAINED 10-15 KT ATTM. HWVR...SLY CHANNELING FCST TNGT
OVER THE MD BAY/LWR PTMC. MARGINAL WINDS /MAYBE JUST SHY OF ADVY/
FCST TO CONT THRU THE DAY THU...SPCLY AHD OF CDFNT. SCA ALREADY IN
PLACE. LOOKS SOLID TNGT...AND DO NOT HV CONFIDENCE TO REMOVE IT
FOR TMRW AT THIS JUNCTURE.
BRIEF PERIOD OF SCA GUSTS EARLY FRIDAY MORNING ON THE CHESAPEAKE
BAY...WITH ALL WATERS BCMG SUB-SCA BY FRI AFT. SUB-SCA CONDITIONS
THEN LASTING INTO THE WEEKEND.
&&
.TIDES/COASTAL FLOODING...
WATER LVLS RUNNING ABT A HALF FOOT ABV ASTRO NORMALS THIS EVENING.
HWVR...THERE IS STRONG CONSENSUS AMONGST WATER LVL MODELS THAT THE
UPCOMING HIGH TIDE WL ECLIPSE THE MINOR FLOOD THRESHOLD AT
ANNAPOLIS...WHICH HAS BEEN SUPPORTED BY LATEST RUNS. ONLY A SLGT
INCREASE IN THE CURRENT DEPARTURE WOULD BE SUFFICIENT TO BEAR THIS
OUT. HAVE OPTED TO ISSUE ADVY FOR AA COUNTY. HIGH TIDE AT APAM2
AT 5AM.
NO OTHER SITE IN JEOPARDY ATTM...ALTHO BALTIMORE CITY/COUNTY AND
WASD2 WL GET AWFULLY CLOSE. THE BALTIMORE HIGH TIDE RUNS BETWEEN
6-8 AM. AT SW DC HIGH TIDE IS APPROX 730 AM.
THE PM TIDE WILL BE THE LOWER OF THE TWO ASTRONOMICALLY. NW WINDS
THEREAFTER SUGGEST THE UPCOMING TIDE WILL BE THE ONLY ONE TO WATCH
CLOSELY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...COASTAL FLOOD ADVISORY FROM 2 AM TO 8 AM EDT THURSDAY FOR
MDZ014.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THURSDAY FOR ANZ530>534-
537-539>541-543.
&&
$$
SYNOPSIS...LFR/HTS
NEAR TERM...HTS/LFR
SHORT TERM...SEARS
LONG TERM...IMR
AVIATION...HTS/SEARS/IMR
MARINE...HTS/SEARS/IMR
TIDES/COASTAL FLOODING...HTS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
850 PM EDT WED JUL 29 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA LATE THURSDAY. HIGH PRESSURE WILL
BUILD FOR THE WEEKEND AND HOLD THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
PCPN CVRG HAS BEEN MUCH SPOTTIER...AND LIGHTER...THAN THIS TIME
YDA. WARM LYR BTWN H6-4 ON 00Z LWX RAOB LKLY THE REASON WHY. RDR
TRENDS SEEM TO HV BEEN CAPTURED BY THE HRRR QUITE WELL. STORMS E
OF THE BLURDG HV DSPTD...W/ ONLY A FEW CELLS IN THE PTMC
HIGHLANDS. IF LTST CYCLE OUTPUT VERIFIES...EVEN THIS ACTIVITY WL
ERODE BEFORE MIDNGT...W/ NOT MUCH GOING ON TIL NEW CELLS APPROACH
THE APLCNS PREDAWN. HV ADAPTED GRIDS TWD THIS DIRECTION...BUT HV
HELD ONTO LOW POPS IN THE MTNS. THAT CAN BE REEVALUATED.
NOT NEARLY AS MUCH WET GRND AS PAST CPL NGTS. HWVR A FAIR AMT OF
CLR SKIES AND DEWPTS IN THE LWR-MID 70S SUGGESTS THERE WL ONCE AGN
BE POTL FOR FOG DVLPMNT. HV KEPT IT PATCHY AND NOT DENSE DUE TO
REASONS MENTIONED ABV...SITUATED ALONG/W OF BLURDG AS WELL AS
ACRS NRN MD.
CDFNT CURRENTLY MOVING THROUGH THE MIDWEST WILL ENTER THE FCST
AREA AROUND 18Z THU AND SHOULD CLEAR THE FCST AREA BY 03Z FRI.
FRONT WILL BE LOSING MUCH OF ITS PUNCH BUT IT APPEARS THERE COULD
BE A QUICK BAND OF -SHRA/TSRA RIGHT ALONG OR JUST BEHIND THE
FRONT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
12Z MODEL SUITE HAS THE COLD FRONT PLACED JUST SOUTHEAST OF THE
CWA BY 12Z FRIDAY. ANY LINGERING PCPN WITH THE FRONT SHOULD REMAIN
TO THE SOUTH AS THE FRONTAL BOUNDARY STALLS AND EVENTUALLY
DISSIPATES OVER THE WEEKEND. SFC HIGH PRESSURE BUILDS IN FROM THE
WEST IN THE WAKE. THE REGION WILL REMAIN AT THE SOUTHERN FRINGE OF
BROAD CLOSED LOW OVER CANADA...WITH THE SHORTWAVE ENERGY ROUNDING
THE LOW REMAINING WELL TO THE NORTH. AS SUCH...EXPECTING DRY WX
FRI AND FRI NIGHT. 12Z GFS SUGGESTING LIGHT PCPN OVER NORTHEASTERN
AREAS OF THE CWA SAT AFTN WITH A SHORTWAVE JUST TO THE NORTH. WILL
KEEP THINGS DRY FOR NOW THOUGH DURING THIS TIME WITH LACK OF SFC
FORCING CURRENTLY NOTED.
QUICK SHOT OF CAA IN THE WAKE OF THE FRONT ON FRIDAY DROP 850MB
TEMPS TO AROUND 15 DEGREES CELSIUS...RESULTING IN HIGHS GENERALLY IN
THE 80S. THE COOLER AIRMASS WILL BE SHORT LIVED AS THE HIGH BUILDS
IN...WITH 850MB TEMPS REBOUNDING BACK TO NEAR 20 DEGREES CELSIUS BY
SAT AFTN. LOWS FRIDAY NEAR NORMAL...WITH HIGHS NEARING 90 ON
SATURDAY. DEW PTS IN THE 60S SAT SHOULD KEEP HEAT INDICES WELL BELOW
ADVISORY LVLS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
QUIET WEATHER PATTERN FOR SUN INTO MON WITH HIGH PRESS DOMINATING
CONDITIONS BEHIND A COLD FRONT. THE FRONT LINGERS OFF THE DELMARVA
COAST AS IT WEAKENS... THEREFORE CANNOT RULE OUT SOME SHOWERS TO
THE SE AND E OF OUR CWA. SHORTWAVE TROUGH COULD BRING SOME AFTN
SHOWERS ON MON AND TUE... BUT CONFIDENCE WITH IT IS LOW ATTM... SO
HAVE KEPT LOW POPS. ANOTHER FRONT APPROACHES ON WED INCREASING THE
CHANCE OF SHOWERS AND TSTMS FOR THIS DAY. TEMPS WILL NEAR NORMAL
SUN AND GRADUALLY INCREASING INTO HE LOW 90S FOR WED.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
VFR CONDS ACRS THE TERMINALS ATTM. SETUP SEEMS FVRBL FOR FOG
DVLPMNT ONCE AGN BTWN MIDNGT-DAWN. HWVR NOT AS MUCH WET GRND AS
PAST NGTS...WHICH IS COUNTERED BY HIER DEWPTS/LLVL HUMIDITY.
UNSURE EXACTLY HOW THESE TWO FACTORS WL BALANCE EACH OTHER. HV
OPTED TO KEEP PROLONGED MVFR CONDS OVNGT AT MRB...IFR AT CHO
WHERE SHRA WAS RECVD...AND ONLY BRIEF MVFR AT SUNRISE IAD/MTN. DO
NOT HV HIGH CONFIDENCE ATTM. CUD SEE FLGT CONDS WORSE THAN FCST
BUT WAS HESITANT ON OFFERING UP PROLONGED RESTRICTIONS.
FLGT RESTRICTIONS FOR THE MRNG PUSH WL ERODE BY MID MRNG. A CDFNT
WL CROSS THE TERMINALS DURING THE AFTN...AFFECTING THAT PUSH AS
WELL. SCT-NRMS SHRA/TSRA WL BE FOUND ALONG/AHD OF THE FNT. THINK
THERE WL BE SOME DIURNAL STRENGTHENING...AND AM CARRYING VCTS FOR
DC/BALT TERMINALS AS A RESULT. WUD NOT COMPLETELY RULE OUT IMPACT
AT CHO/MRB BUT PROBABILITY IS LESS. IN THE EVENT OF A DIRECT HIT
BRIEF AOB IFR CAN BE ANTICIPATED. TIMING/SPATIAL UNCERTANTIES
PRECLUDE CARRYING ANY SPECIFIC MENTION ATTM. WSHFT NEAR 18Z AT
MRB...SPREADING EAST TO 21-22Z DCA/BWI.
VFR CONDITIONS FRIDAY AND SATURDAY. WINDS GENERALLY 10 KTS OR
LESS...SHIFTING FROM THE NW FRIDAY TO A WESTERLY FLOW SAT.
&&
.MARINE...
SLY WNDS SUSTAINED 10-15 KT ATTM. HWVR...SLY CHANNELING FCST TNGT
OVER THE MD BAY/LWR PTMC. MARGINAL WINDS /MAYBE JUST SHY OF ADVY/
FCST TO CONT THRU THE DAY THU...SPCLY AHD OF CDFNT. SCA ALREADY IN
PLACE. LOOKS SOLID TNGT...AND DO NOT HV CONFIDENCE TO REMOVE IT
FOR TMRW AT THIS JUNCTURE.
BRIEF PERIOD OF SCA GUSTS EARLY FRIDAY MORNING ON THE CHESAPEAKE
BAY...WITH ALL WATERS BCMG SUB-SCA BY FRI AFT. SUB-SCA CONDITIONS
THEN LASTING INTO THE WEEKEND.
&&
.TIDES/COASTAL FLOODING...
WATER LVLS RUNNING ABT A HALF FOOT ABV ASTRO NORMALS THIS EVENING.
HWVR...THERE IS STRONG CONSENSUS AMONGST WATER LVL MODELS THAT THE
UPCOMING HIGH TIDE WL ECLIPSE THE MINOR FLOOD THRESHOLD AT
ANNAPOLIS. ONLY A SLGT INCREASE IN THE CURRENT DEPARTURE WOULD BE
SUFFICIENT TO BEAR THIS OUT. HIGH TIDE AT APAM2 AT 5AM. WL BE
AWAITING THE LATEST GUIDANCE. CONSISTENCY SUGGESTS THAT AN ADVY
MAY BE WARRANTED.
NO OTHER SITE IN JEOPARDY ATTM...ALTHO WASD2 WL GET AWFULLY CLOSE
FOR 730 AM HIGH TIDE.
THE PM TIDE WILL BE THE LOWER OF THE TWO ASTRONOMICALLY. NW WINDS
THEREAFTER SUGGEST THE UPCOMING TIDE WILL BE THE ONLY ONE TO WATCH
CLOSELY.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THURSDAY FOR ANZ530>534-
537-539>541-543.
&&
$$
SYNOPSIS...LFR/HTS
NEAR TERM...HTS/LFR
SHORT TERM...SEARS
LONG TERM...IMR
AVIATION...HTS/SEARS/IMR
MARINE...HTS/SEARS/IMR
TIDES/COASTAL FLOODING...HTS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
334 PM EDT TUE JUL 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 606 AM EDT TUE JUL 28 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER
THE NRN ROCKIES AND HIGH PLAINS AND A RIDGE FROM THE SRN PLAINS
THROUGH THE GREAT LAKES REGION INTO NRN ONTARIO. WITHIN BASE OF MID-
LEVEL TROUGH A STRONG SHORTWAVE AND DEVELOPING CLOSED LOW WAS
LIFTING NE FROM ERN MONTANA INTO THE WRN DAKOTAS. INSTABILITY
(MUCAPES 1000-2000 J/KG) AND LIFT AHEAD OF SHORTWAVE AND ALONG ASSOC
FRONTAL BOUNDARY HAS SUPPORTED A LARGE MCS OVER THE ERN DAKOTAS AND
WRN MN EARLY THIS MORNING. BY COMPARISION...HIGH PRESSURE OVER THE
GREAT LAKES REGION HAS RESULTED IN GENERALLY CLOUD FREE AND QUIET
CONDITIONS OVER UPPER MI...ALTHOUGH NIGHTTIME TEMPS HAVE BEEN QUITE
WARM... GENERALLY IN THE 60S.
MODELS INDICATE CLOUDS AND POSSIBLY A FEW SHRA FROM DIMINISHING
CONVECTION WITH MCS TO WEST COULD SPREAD INTO WRN UPPER MI THIS
AFTERNOON. DESPITE POSSIBLE INCREASE IN CLOUDS...EXPECT ENOUGH
SUNSHINE BY AFTERNOON TO PUSH TEMPS INTO THE UPPER 80S AND LOWER 90S
AS MOST LOCATIONS AGAIN TODAY. WITH DAYTIME MIXING EXPECT DEWPOINTS
TO LOWER INTO MID TO UPPER 50S AT MOST LOCATIONS WITH EVEN A FEW
LOWER 50S DEWPOINTS POSSIBLE OVER EASTERN SITES. COMBINATION OF HIGH
TEMPS AND LOWERING OF DEWPOINTS WILL RESULT IN INLAND MIN RH/S
DROPPING INTO THE 30S OVER MUCH OF CENTRAL UPPER MI WITH EVEN SOME
MID TO UPPER 20S RH/S OVER THE ERN THIRD OF UPPER MI. THIS WILL
INCREASE FIRE WEATHER CONCERNS TODAY INTO THIS EVENING GIVEN RECENT
STRETCH OF DRY WEATHER. FORTUNATELY SOUTHERLY WINDS AHEAD OF FRONT
SHOULDN/T INCREASE TOO MUCH THROUGH THIS EVENING (GENERALLY LESS
THAN 20 MPH FOR GUSTS). WEST WINDS HOWEVER COULD GET GUSTY IN WAKE
OF FRONT ON WEDNESDAY.
FOCUSING ON PCPN CHCS THIS AFTERNOON INTO TONIGHT AS FRONTAL SYSTEM
FROM PLAINS WORKS ITS WAY ACROSS THE REGION TONIGHT INTO EARLY
WEDNESDAY. MODELS SHOW SOME DIFFERENCES IN FRONTAL TIMING WITH THE
REGIONAL GEM PERHAPS A BIT QUICKER WITH FRONT INITIALLY THAN
NAM...GFS OR ECMWF MODELS. DESPITE MINOR DIFFERENCES MODELS
GENERALLY SHOW COLD FRONT REACHING INTO WRN UPPER MI THIS
EVENING...INTO CENTRAL UPPER MI AROUND 12Z WED AND EXITING ERN UPPER
MI AROUND 18Z WED. MODELS CONSISTENT WITH IDEA THAT BEST DYNAMICS
(MID-LVL Q-VECT CONV) ASSOC WITH FRONTAL SYSTEM WILL BE LIFTING WEST
AND NORTH OF THE UPPER GREAT LAKES TONIGHT...TIED TO MOVEMENT OF
SHORTWAVE AND ASSOC MID-LVL CLOSED LOW WHICH LIFT NE INTO SRN
MANITOBA AND NW ONTARIO TONIGHT. AT SAME TIME...MODELS AND SREF
ENSEMBLE FIELDS INDICATE BEST MOISTURE/INSTABILITY STAYING SOUTH OF
UPPER MI INTO WI BY TIME FRONT MOVES THROUGH TONIGHT WITH MUCAPES
500 TO MAYBE 1000 J/KG FAR WEST IN THE EVENING DECREASING TO ONLY A
FEW HUNDRED J/KG EAST OVERNIGHT. COMBINATION OF BEST DYNAMICS MOVING
WELL TO NORTH AND BEST MOISTURE STAYING SOUTH HAS LED MOST OF
MODELS TO DEPICT MORE A SCATTERED TO BROKEN LINE OF CONVECTION
DEVELOPING ALONG FRONT AS IT MOVES THROUGH UPPER MI TONIGHT. GIVEN
THE UNCERTAINTY WITH DEVELOPING CONVECTION ALONG FRONT HAVE
GENERALLY KEPT ONLY HIGH CHC POPS AND LIMITED LIKELY POPS IN FCST
FOR SCT SHRA/TSRA LATE THIS AFTERNOON/EARLY EVENING WEST SPREADING
ACROSS REST OF FCST TONIGHT.
ALSO DOWNPLAYED THREAT OF SEVERE STORMS IN HWO GIVEN LATER TIMING OF
FRONT TOWARD LATE EVENING OVERNIGHT AS INSTABILITY WILL BE WANING.
ALSO BEST DEEP SHEAR LOOKS TO LAG BEHIND THE FRONT AND OUT OF SYNC
WITH BETTER INSTABILITY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 333 PM EDT TUE JUL 28 2015
IMPACTS...MAIN IMPACTS WILL BE ASSOCIATED WITH GUSTY WINDS WED NIGHT
AND THU.
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH
REGIONALLY THROUGH THE LONG TERM. A LOW PRESSURE SYSTEM OVER FAR NRN
ONTARIO AT 00Z THU WILL MOVE TO HUDSON BAY BY 00Z FRI AND MEANDER
OVER THE BAY INTO THE WEEKEND. THE LOW WILL THEN BEHIND THE CYCLE
BACK TO THE W...POSSIBLY BRINGING AN UPPER TROUGH OVER THE AREA LATE
THIS WEEKEND INTO NEXT WEEK.
THE PRESSURE GRADIENT...AND THEREFOR WINDS...WILL BE TIGHTEST OVER
THE AREA WED NIGHT...AND WILL GRADUALLY WEAKEN INTO SAT. WINDS GUSTS
AT 00Z THU WILL RANGE FROM 30-35MPH OVER THE KEWEENAW TO 10-20MPH
N/NE OF LAKE MICHIGAN. A TROUGH MOVES THROUGH WED NIGHT THAT MAY
LOCALLY ENHANCE WINDS OVER/NEAR LAKE SUPERIOR...BUT WINDS WILL
GENERALLY BE STRONGEST AT 00Z THU AND GRADUALLY DIMINISHING AFTER
THAT. ANOTHER MOISTURE STARVED TROUGH OR TWO MOVES THROUGH ON
THU...BUT WILL ONLY PROVIDE SOME INCREASED CLOUD COVER.
A SHORTWAVE WITH LIMITED MOISTURE MOVES THROUGH THU NIGHT...WHICH
JUSTIFIES SLIGHT CHANCE POPS AS MODELS SHOW LIGHT QPF AMOUNTS OVER
MUCH OF THE AREA.
FRI INTO SAT LOOKS DRY...ALTHOUGH THE 12Z/28 GFS DOES BRING A PRECIP
PRODUCING SHORTWAVE INTO THE AREA FRI NIGHT. LEFT PRECIP OUT OF THE
FORECAST SINCE THE PREVIOUS GFS RUN WAS DRY AND OTHER MODELS ARE
DRY.
TEMPERATURES THU THROUGH SAT WILL BE NEAR NORMAL WITH HIGHS IN THE
70S TO LOW 80S AND LOW IN THE 50S TO LOW 60S.
MODELS SHOW A MORE SIGNIFICANT SHORTWAVE AND WIDESPREAD QPF SAT
NIGHT INTO SUN SO WILL KEEP CHANCE POPS FOR THAT TIME FRAME. COOLER
TEMPS COME IN WITH THAT UPPER TROUGH EARLY NEXT WEEK...BRINGING
BELOW NORMAL TEMPS FOR A CHANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 159 PM EDT TUE JUL 28 2015
HIGH CLOUDS WILL BEGIN TO LOWER THIS EVENING RIGHT AHEAD AND ALONG A
COLD FRONT CROSSING W TO E OVER THE AREA. WHILE THUNDERSTORMS WILL
BE POSSIBLE...THE TIMING AND OVERALL COVERAGE IS TOO SMALL TO
INCLUDE IN THE TAF RIGHT NOW. LLWS IS A CONCERN THIS EVENING INTO
THE EARLY MORNING HOURS WEDNESDAY AS WINDS JUST ABOVE THE SFC
CONTINUE AROUND 35KTS. EXPECT THE GUSTY WINDS TO MIX BETTER DURING
THE DAY...LIMITING THE NEED FOR LLWS. EXPECT SIGNIFICANT CLEARING
AND MIXING DIRECTLY BEHIND THE FRONT...WITH SOME SCT-BKN VFR CLOUDS
ENCROACHING BY MID AFTERNOON.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 159 PM EDT TUE JUL 28 2015
FOLLOWING THE PASSAGE OF A COLD FRONT LATE TONIGHT AND WED
MORNING...THE SHARPENING PRES GRADIENT OVER THE UPPER LAKES BETWEEN
HI PRES BUILDING INTO THE CENTRAL PLAINS AND LO PRES MOVING TOWARD
HUDSON BAY WILL SUPPORT WSW GALES UP TO 35 KTS THRU THE DAY ON WED
OVER THE W HALF OF THE LAKE...WHERE THE LAKE GEOGRAPHY TYPICALLY
ENHANCES THIS FLOW. MAINTAINED GOING GALE WATCH FOR THIS AREA.
ALTHOUGH THE GALES ARE EXPECTED TO DIMINISH ON WED EVENING... WINDS
UP TO 25-30 KTS WILL PERSIST THRU THU AS THE PRES GRADIENT SLOWLY
SLACKENS. LIGHTER WINDS UNDER 20 KTS WILL THEN BE THE RULE ON FRI
THRU THE WEEKEND AS A WEAKER PRES GRADIENT MORE TYPICAL OF SUMMER
DOMINATES THAT PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING FOR
LSZ162-240>247-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
200 PM EDT TUE JUL 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 606 AM EDT TUE JUL 28 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER
THE NRN ROCKIES AND HIGH PLAINS AND A RIDGE FROM THE SRN PLAINS
THROUGH THE GREAT LAKES REGION INTO NRN ONTARIO. WITHIN BASE OF MID-
LEVEL TROUGH A STRONG SHORTWAVE AND DEVELOPING CLOSED LOW WAS
LIFTING NE FROM ERN MONTANA INTO THE WRN DAKOTAS. INSTABILITY
(MUCAPES 1000-2000 J/KG) AND LIFT AHEAD OF SHORTWAVE AND ALONG ASSOC
FRONTAL BOUNDARY HAS SUPPORTED A LARGE MCS OVER THE ERN DAKOTAS AND
WRN MN EARLY THIS MORNING. BY COMPARISION...HIGH PRESSURE OVER THE
GREAT LAKES REGION HAS RESULTED IN GENERALLY CLOUD FREE AND QUIET
CONDITIONS OVER UPPER MI...ALTHOUGH NIGHTTIME TEMPS HAVE BEEN QUITE
WARM... GENERALLY IN THE 60S.
MODELS INDICATE CLOUDS AND POSSIBLY A FEW SHRA FROM DIMINISHING
CONVECTION WITH MCS TO WEST COULD SPREAD INTO WRN UPPER MI THIS
AFTERNOON. DESPITE POSSIBLE INCREASE IN CLOUDS...EXPECT ENOUGH
SUNSHINE BY AFTERNOON TO PUSH TEMPS INTO THE UPPER 80S AND LOWER 90S
AS MOST LOCATIONS AGAIN TODAY. WITH DAYTIME MIXING EXPECT DEWPOINTS
TO LOWER INTO MID TO UPPER 50S AT MOST LOCATIONS WITH EVEN A FEW
LOWER 50S DEWPOINTS POSSIBLE OVER EASTERN SITES. COMBINATION OF HIGH
TEMPS AND LOWERING OF DEWPOINTS WILL RESULT IN INLAND MIN RH/S
DROPPING INTO THE 30S OVER MUCH OF CENTRAL UPPER MI WITH EVEN SOME
MID TO UPPER 20S RH/S OVER THE ERN THIRD OF UPPER MI. THIS WILL
INCREASE FIRE WEATHER CONCERNS TODAY INTO THIS EVENING GIVEN RECENT
STRETCH OF DRY WEATHER. FORTUNATELY SOUTHERLY WINDS AHEAD OF FRONT
SHOULDN/T INCREASE TOO MUCH THROUGH THIS EVENING (GENERALLY LESS
THAN 20 MPH FOR GUSTS). WEST WINDS HOWEVER COULD GET GUSTY IN WAKE
OF FRONT ON WEDNESDAY.
FOCUSING ON PCPN CHCS THIS AFTERNOON INTO TONIGHT AS FRONTAL SYSTEM
FROM PLAINS WORKS ITS WAY ACROSS THE REGION TONIGHT INTO EARLY
WEDNESDAY. MODELS SHOW SOME DIFFERENCES IN FRONTAL TIMING WITH THE
REGIONAL GEM PERHAPS A BIT QUICKER WITH FRONT INITIALLY THAN
NAM...GFS OR ECMWF MODELS. DESPITE MINOR DIFFERENCES MODELS
GENERALLY SHOW COLD FRONT REACHING INTO WRN UPPER MI THIS
EVENING...INTO CENTRAL UPPER MI AROUND 12Z WED AND EXITING ERN UPPER
MI AROUND 18Z WED. MODELS CONSISTENT WITH IDEA THAT BEST DYNAMICS
(MID-LVL Q-VECT CONV) ASSOC WITH FRONTAL SYSTEM WILL BE LIFTING WEST
AND NORTH OF THE UPPER GREAT LAKES TONIGHT...TIED TO MOVEMENT OF
SHORTWAVE AND ASSOC MID-LVL CLOSED LOW WHICH LIFT NE INTO SRN
MANITOBA AND NW ONTARIO TONIGHT. AT SAME TIME...MODELS AND SREF
ENSEMBLE FIELDS INDICATE BEST MOISTURE/INSTABILITY STAYING SOUTH OF
UPPER MI INTO WI BY TIME FRONT MOVES THROUGH TONIGHT WITH MUCAPES
500 TO MAYBE 1000 J/KG FAR WEST IN THE EVENING DECREASING TO ONLY A
FEW HUNDRED J/KG EAST OVERNIGHT. COMBINATION OF BEST DYNAMICS MOVING
WELL TO NORTH AND BEST MOISTURE STAYING SOUTH HAS LED MOST OF
MODELS TO DEPICT MORE A SCATTERED TO BROKEN LINE OF CONVECTION
DEVELOPING ALONG FRONT AS IT MOVES THROUGH UPPER MI TONIGHT. GIVEN
THE UNCERTAINTY WITH DEVELOPING CONVECTION ALONG FRONT HAVE
GENERALLY KEPT ONLY HIGH CHC POPS AND LIMITED LIKELY POPS IN FCST
FOR SCT SHRA/TSRA LATE THIS AFTERNOON/EARLY EVENING WEST SPREADING
ACROSS REST OF FCST TONIGHT.
ALSO DOWNPLAYED THREAT OF SEVERE STORMS IN HWO GIVEN LATER TIMING OF
FRONT TOWARD LATE EVENING OVERNIGHT AS INSTABILITY WILL BE WANING.
ALSO BEST DEEP SHEAR LOOKS TO LAG BEHIND THE FRONT AND OUT OF SYNC
WITH BETTER INSTABILITY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM EDT TUE JUL 28 2015
A 991MB SURFACE LOW WILL BE LIFTING NORTHEAST ALONG THE
MANITOBA/ONTARIO BORDER AT 12Z WEDNESDAY...WITH A COLD FRONT
STRETCHING SOUTH-SOUTHEAST ACROSS CENTRAL LAKE SUPERIOR AND THROUGH
CENTRAL UPPER MICHIGAN AND SOUTH THROUGH EASTERN WISCONSIN. EXPECT
A BROKEN LINE OF SHOWERS AND THUNDERSTORMS TO BE ONGOING ALONG AND
TO THE EAST OF THE COLD FRONT. WITH INSTABILITY DECREASING THROUGH
THE NIGHT...DON/T EXPECT ANY REALLY STRONG STORMS...ALTHOUGH BRIEF
PERIODS OF HEAVY RAIN IS EXPECTED. THESE SHOWERS/THUNDERSTORMS WILL
CONTINUE TO THE EAST-NORTHEAST THROUGH THE MORNING AND SHOULD LEAVE
THE CWA BY EARLY AFTERNOON (ALONG WITH THE COLD FRONT). THAT COLD
FRONT WILL BRING TEMPERATURE/HUMIDITY RELIEF TO THE REGION ON
WEDNESDAY...AS MUCH DRIER LOW LEVEL AIR MOVES OVER THE REGION AND
HIGHS ONLY RISE INTO THE UPPER 70S WEST AND LOWER 80S EAST. AFTER
CLEARING INITIALLY BEHIND THE FRONT...EXPECT SCATTERED CLOUDS TO
MOVE EAST BACK INTO THE AREA FROM LATE MORNING OVER THE WEST TO THE
AFTERNOON OVER THE CENTRAL...TIED TO 850-700MB MOISTURE ASSOCIATED
WITH THE SOUTHERN EDGE OF THE UPPER TROUGH SWEEPING EAST THROUGH THE
AREA. THE MAIN HAZARD FOR WEDNESDAY WILL BE THE GUSTY WEST-SOUTHWEST
WINDS...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN AND
LAKE SUPERIOR. MODELS STILL SHOWING A CORE OF 30-45KT 950-900MB
WINDS MOVING OVER THE AREA ON WEDNESDAY AND ASSOCIATED WITH THE
TIGHT PRESSURE GRADIENT BEHIND THE DEPARTING LOW (TIGHTEST FROM THE
KEWEENAW PENINSULA AND NORTH). WITH THE WESTERN LAKE WARMING
UP...DON/T THINK THE MARINE LAYER WILL HAVE AS MUCH OF AN AFFECT AS
EARLIER IN THE YEAR AND FEEL PRETTY COMFORTABLE IN HAVING GUSTS TO
35-40KTS OVER LSZ263-264. THUS...WILL ISSUE A GALE WATCH FOR
WEDNESDAY FOR THE WESTERN HALF OF THE LAKE. OVER THE LAND...STILL
EXPECT THE HIGHEST GUSTS TO OCCUR OVER THE KEWEENAW PENINSULA...WITH
AFTERNOON GUSTS OF 30-40MPH AND MAYBE A FEW GUSTS UP TO 45MPH AROUND
THE BROCKWAY MOUNTAIN AREA. A SECONDARY TROUGH WILL SWEEP ACROSS THE
AREA ON WEDNESDAY EVENING...SWITCHING WINDS TO THE WEST-NORTHWEST
BUT HAVING LITTLE EFFECT ON THE LOW LEVEL WINDS. THIS WILL LIKELY
KEEP SUSTAINED WINDS UP THROUGH MUCH OF THE NIGHT AND POSSIBLY KEEP
GALES GOING OVER THE NORTHERN LAKE INTO THURSDAY MORNING. WITH
LIMITED MOISTURE ASSOCIATED WITH THE FRONTAL PASSAGE...DON/T EXPECT
ANYTHING MORE THAN A FEW TO SCATTERED CLOUDS MOVING THROUGH THE AREA
ON WEDNESDAY NIGHT.
THAT WILL BE THE STORY FOR THE NEXT SEVERAL WAVES DROPPING
SOUTHEAST ACROSS THE AREA UNDER NORTHWEST FLOW ALOFT (OCCURRING
ABOUT EVERY 8-12HOURS INTO THE WEEKEND). THESE SERIES OF WAVES WILL
OCCUR ON THE SOUTH SIDE OF A THE SURFACE AND UPPER LOW MOVING
NORTHEAST ACROSS SOUTHERN HUDSON BAY. MOST WILL BE MOISTURE STARVED
AND WILL LARGELY SHOW PASSING CLOUDS WITH THEM...AND JUST SOME
SLIGHT CHANCES FOR THE THURSDAY NIGHT INTO FRIDAY PERIOD OVER THE
NORTHEAST. WINDS WILL STILL BE GUSTY ON THURSDAY...BUT GRADUALLY
DIMINISH HEADING INTO SATURDAY AS A HIGH PRESSURE RIDGE MOVES OVER
THE AREA. TEMPERATURES WILL BE NEAR NORMAL DURING THIS PERIOD AND
IN THE UPPER 70S TO LOWER 80S. MODELS STILL INDICATING THE BEST
CHANCE FOR PRECIPITATION TO OCCUR WITH ANOTHER SHORTWAVE AND
STRONGER FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING. WILL CONTINUE
TO MENTION CHANCE POPS DURING THAT PERIOD.
MODELS DIVERGE HEADING INTO NEXT WEEK ON THE TIMING OF THE UPPER
LOW SPINNING OVER HUDSON BAY DROPPING SOUTH TOWARDS THE GREAT LAKES
REGION. WHEN THIS OCCURS...IT WILL MARK A SHIFT TO BELOW NORMAL
TEMPERATURES THAT HAS BEEN SHOWN RECENTLY ON THE CFS AND LONG RANGE
ECMWF ENSEMBLES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 159 PM EDT TUE JUL 28 2015
HIGH CLOUDS WILL BEGIN TO LOWER THIS EVENING RIGHT AHEAD AND ALONG A
COLD FRONT CROSSING W TO E OVER THE AREA. WHILE THUNDERSTORMS WILL
BE POSSIBLE...THE TIMING AND OVERALL COVERAGE IS TOO SMALL TO
INCLUDE IN THE TAF RIGHT NOW. LLWS IS A CONCERN THIS EVENING INTO
THE EARLY MORNING HOURS WEDNESDAY AS WINDS JUST ABOVE THE SFC
CONTINUE AROUND 35KTS. EXPECT THE GUSTY WINDS TO MIX BETTER DURING
THE DAY...LIMITING THE NEED FOR LLWS. EXPECT SIGNIFICANT CLEARING
AND MIXING DIRECTLY BEHIND THE FRONT...WITH SOME SCT-BKN VFR CLOUDS
ENCROACHING BY MID AFTERNOON.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 159 PM EDT TUE JUL 28 2015
FOLLOWING THE PASSAGE OF A COLD FRONT LATE TONIGHT AND WED
MORNING...THE SHARPENING PRES GRADIENT OVER THE UPPER LAKES BETWEEN
HI PRES BUILDING INTO THE CENTRAL PLAINS AND LO PRES MOVING TOWARD
HUDSON BAY WILL SUPPORT WSW GALES UP TO 35 KTS THRU THE DAY ON WED
OVER THE W HALF OF THE LAKE...WHERE THE LAKE GEOGRAPHY TYPICALLY
ENHANCES THIS FLOW. MAINTAINED GOING GALE WATCH FOR THIS AREA.
ALTHOUGH THE GALES ARE EXPECTED TO DIMINISH ON WED EVENING... WINDS
UP TO 25-30 KTS WILL PERSIST THRU THU AS THE PRES GRADIENT SLOWLY
SLACKENS. LIGHTER WINDS UNDER 20 KTS WILL THEN BE THE RULE ON FRI
THRU THE WEEKEND AS A WEAKER PRES GRADIENT MORE TYPICAL OF SUMMER
DOMINATES THAT PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING FOR
LSZ162-240>247-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
748 AM EDT TUE JUL 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 606 AM EDT TUE JUL 28 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER
THE NRN ROCKIES AND HIGH PLAINS AND A RIDGE FROM THE SRN PLAINS
THROUGH THE GREAT LAKES REGION INTO NRN ONTARIO. WITHIN BASE OF MID-
LEVEL TROUGH A STRONG SHORTWAVE AND DEVELOPING CLOSED LOW WAS
LIFTING NE FROM ERN MONTANA INTO THE WRN DAKOTAS. INSTABILITY
(MUCAPES 1000-2000 J/KG) AND LIFT AHEAD OF SHORTWAVE AND ALONG ASSOC
FRONTAL BOUNDARY HAS SUPPORTED A LARGE MCS OVER THE ERN DAKOTAS AND
WRN MN EARLY THIS MORNING. BY COMPARISION...HIGH PRESSURE OVER THE
GREAT LAKES REGION HAS RESULTED IN GENERALLY CLOUD FREE AND QUIET
CONDITIONS OVER UPPER MI...ALTHOUGH NIGHTTIME TEMPS HAVE BEEN QUITE
WARM... GENERALLY IN THE 60S.
MODELS INDICATE CLOUDS AND POSSIBLY A FEW SHRA FROM DIMINISHING
CONVECTION WITH MCS TO WEST COULD SPREAD INTO WRN UPPER MI THIS
AFTERNOON. DESPITE POSSIBLE INCREASE IN CLOUDS...EXPECT ENOUGH
SUNSHINE BY AFTERNOON TO PUSH TEMPS INTO THE UPPER 80S AND LOWER 90S
AS MOST LOCATIONS AGAIN TODAY. WITH DAYTIME MIXING EXPECT DEWPOINTS
TO LOWER INTO MID TO UPPER 50S AT MOST LOCATIONS WITH EVEN A FEW
LOWER 50S DEWPOINTS POSSIBLE OVER EASTERN SITES. COMBINATION OF HIGH
TEMPS AND LOWERING OF DEWPOINTS WILL RESULT IN INLAND MIN RH/S
DROPPING INTO THE 30S OVER MUCH OF CENTRAL UPPER MI WITH EVEN SOME
MID TO UPPER 20S RH/S OVER THE ERN THIRD OF UPPER MI. THIS WILL
INCREASE FIRE WEATHER CONCERNS TODAY INTO THIS EVENING GIVEN RECENT
STRETCH OF DRY WEATHER. FORTUNATELY SOUTHERLY WINDS AHEAD OF FRONT
SHOULDN/T INCREASE TOO MUCH THROUGH THIS EVENING (GENERALLY LESS
THAN 20 MPH FOR GUSTS). WEST WINDS HOWEVER COULD GET GUSTY IN WAKE
OF FRONT ON WEDNESDAY.
FOCUSING ON PCPN CHCS THIS AFTERNOON INTO TONIGHT AS FRONTAL SYSTEM
FROM PLAINS WORKS ITS WAY ACROSS THE REGION TONIGHT INTO EARLY
WEDNESDAY. MODELS SHOW SOME DIFFERENCES IN FRONTAL TIMING WITH THE
REGIONAL GEM PERHAPS A BIT QUICKER WITH FRONT INITIALLY THAN
NAM...GFS OR ECMWF MODELS. DESPITE MINOR DIFFERENCES MODELS
GENERALLY SHOW COLD FRONT REACHING INTO WRN UPPER MI THIS
EVENING...INTO CENTRAL UPPER MI AROUND 12Z WED AND EXITING ERN UPPER
MI AROUND 18Z WED. MODELS CONSISTENT WITH IDEA THAT BEST DYNAMICS
(MID-LVL Q-VECT CONV) ASSOC WITH FRONTAL SYSTEM WILL BE LIFTING WEST
AND NORTH OF THE UPPER GREAT LAKES TONIGHT...TIED TO MOVEMENT OF
SHORTWAVE AND ASSOC MID-LVL CLOSED LOW WHICH LIFT NE INTO SRN
MANITOBA AND NW ONTARIO TONIGHT. AT SAME TIME...MODELS AND SREF
ENSEMBLE FIELDS INDICATE BEST MOISTURE/INSTABILITY STAYING SOUTH OF
UPPER MI INTO WI BY TIME FRONT MOVES THROUGH TONIGHT WITH MUCAPES
500 TO MAYBE 1000 J/KG FAR WEST IN THE EVENING DECREASING TO ONLY A
FEW HUNDRED J/KG EAST OVERNIGHT. COMBINATION OF BEST DYNAMICS MOVING
WELL TO NORTH AND BEST MOISTURE STAYING SOUTH HAS LED MOST OF
MODELS TO DEPICT MORE A SCATTERED TO BROKEN LINE OF CONVECTION
DEVELOPING ALONG FRONT AS IT MOVES THROUGH UPPER MI TONIGHT. GIVEN
THE UNCERTAINTY WITH DEVELOPING CONVECTION ALONG FRONT HAVE
GENERALLY KEPT ONLY HIGH CHC POPS AND LIMITED LIKELY POPS IN FCST
FOR SCT SHRA/TSRA LATE THIS AFTERNOON/EARLY EVENING WEST SPREADING
ACROSS REST OF FCST TONIGHT.
ALSO DOWNPLAYED THREAT OF SEVERE STORMS IN HWO GIVEN LATER TIMING OF
FRONT TOWARD LATE EVENING OVERNIGHT AS INSTABILITY WILL BE WANING.
ALSO BEST DEEP SHEAR LOOKS TO LAG BEHIND THE FRONT AND OUT OF SYNC
WITH BETTER INSTABILITY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM EDT TUE JUL 28 2015
A 991MB SURFACE LOW WILL BE LIFTING NORTHEAST ALONG THE
MANITOBA/ONTARIO BORDER AT 12Z WEDNESDAY...WITH A COLD FRONT
STRETCHING SOUTH-SOUTHEAST ACROSS CENTRAL LAKE SUPERIOR AND THROUGH
CENTRAL UPPER MICHIGAN AND SOUTH THROUGH EASTERN WISCONSIN. EXPECT
A BROKEN LINE OF SHOWERS AND THUNDERSTORMS TO BE ONGOING ALONG AND
TO THE EAST OF THE COLD FRONT. WITH INSTABILITY DECREASING THROUGH
THE NIGHT...DON/T EXPECT ANY REALLY STRONG STORMS...ALTHOUGH BRIEF
PERIODS OF HEAVY RAIN IS EXPECTED. THESE SHOWERS/THUNDERSTORMS WILL
CONTINUE TO THE EAST-NORTHEAST THROUGH THE MORNING AND SHOULD LEAVE
THE CWA BY EARLY AFTERNOON (ALONG WITH THE COLD FRONT). THAT COLD
FRONT WILL BRING TEMPERATURE/HUMIDITY RELIEF TO THE REGION ON
WEDNESDAY...AS MUCH DRIER LOW LEVEL AIR MOVES OVER THE REGION AND
HIGHS ONLY RISE INTO THE UPPER 70S WEST AND LOWER 80S EAST. AFTER
CLEARING INITIALLY BEHIND THE FRONT...EXPECT SCATTERED CLOUDS TO
MOVE EAST BACK INTO THE AREA FROM LATE MORNING OVER THE WEST TO THE
AFTERNOON OVER THE CENTRAL...TIED TO 850-700MB MOISTURE ASSOCIATED
WITH THE SOUTHERN EDGE OF THE UPPER TROUGH SWEEPING EAST THROUGH THE
AREA. THE MAIN HAZARD FOR WEDNESDAY WILL BE THE GUSTY WEST-SOUTHWEST
WINDS...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN AND
LAKE SUPERIOR. MODELS STILL SHOWING A CORE OF 30-45KT 950-900MB
WINDS MOVING OVER THE AREA ON WEDNESDAY AND ASSOCIATED WITH THE
TIGHT PRESSURE GRADIENT BEHIND THE DEPARTING LOW (TIGHTEST FROM THE
KEWEENAW PENINSULA AND NORTH). WITH THE WESTERN LAKE WARMING
UP...DON/T THINK THE MARINE LAYER WILL HAVE AS MUCH OF AN AFFECT AS
EARLIER IN THE YEAR AND FEEL PRETTY COMFORTABLE IN HAVING GUSTS TO
35-40KTS OVER LSZ263-264. THUS...WILL ISSUE A GALE WATCH FOR
WEDNESDAY FOR THE WESTERN HALF OF THE LAKE. OVER THE LAND...STILL
EXPECT THE HIGHEST GUSTS TO OCCUR OVER THE KEWEENAW PENINSULA...WITH
AFTERNOON GUSTS OF 30-40MPH AND MAYBE A FEW GUSTS UP TO 45MPH AROUND
THE BROCKWAY MOUNTAIN AREA. A SECONDARY TROUGH WILL SWEEP ACROSS THE
AREA ON WEDNESDAY EVENING...SWITCHING WINDS TO THE WEST-NORTHWEST
BUT HAVING LITTLE EFFECT ON THE LOW LEVEL WINDS. THIS WILL LIKELY
KEEP SUSTAINED WINDS UP THROUGH MUCH OF THE NIGHT AND POSSIBLY KEEP
GALES GOING OVER THE NORTHERN LAKE INTO THURSDAY MORNING. WITH
LIMITED MOISTURE ASSOCIATED WITH THE FRONTAL PASSAGE...DON/T EXPECT
ANYTHING MORE THAN A FEW TO SCATTERED CLOUDS MOVING THROUGH THE AREA
ON WEDNESDAY NIGHT.
THAT WILL BE THE STORY FOR THE NEXT SEVERAL WAVES DROPPING
SOUTHEAST ACROSS THE AREA UNDER NORTHWEST FLOW ALOFT (OCCURRING
ABOUT EVERY 8-12HOURS INTO THE WEEKEND). THESE SERIES OF WAVES WILL
OCCUR ON THE SOUTH SIDE OF A THE SURFACE AND UPPER LOW MOVING
NORTHEAST ACROSS SOUTHERN HUDSON BAY. MOST WILL BE MOISTURE STARVED
AND WILL LARGELY SHOW PASSING CLOUDS WITH THEM...AND JUST SOME
SLIGHT CHANCES FOR THE THURSDAY NIGHT INTO FRIDAY PERIOD OVER THE
NORTHEAST. WINDS WILL STILL BE GUSTY ON THURSDAY...BUT GRADUALLY
DIMINISH HEADING INTO SATURDAY AS A HIGH PRESSURE RIDGE MOVES OVER
THE AREA. TEMPERATURES WILL BE NEAR NORMAL DURING THIS PERIOD AND
IN THE UPPER 70S TO LOWER 80S. MODELS STILL INDICATING THE BEST
CHANCE FOR PRECIPITATION TO OCCUR WITH ANOTHER SHORTWAVE AND
STRONGER FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING. WILL CONTINUE
TO MENTION CHANCE POPS DURING THAT PERIOD.
MODELS DIVERGE HEADING INTO NEXT WEEK ON THE TIMING OF THE UPPER
LOW SPINNING OVER HUDSON BAY DROPPING SOUTH TOWARDS THE GREAT LAKES
REGION. WHEN THIS OCCURS...IT WILL MARK A SHIFT TO BELOW NORMAL
TEMPERATURES THAT HAS BEEN SHOWN RECENTLY ON THE CFS AND LONG RANGE
ECMWF ENSEMBLES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 740 AM EDT TUE JUL 28 2015
HIGH PRESSURE WILL REMAIN IN CONTROL KEEPING DRY CONDITIONS AND VFR
CONDITIONS THROUGH MUCH OF THE DAY FOR THE TAF SITES. EXPECT LOWERING
CIGS FROM THE WEST THIS EVENING WITH INCREASING CHANCES FOR SHRA AND
POSSIBLY THUNDERSTORMS TONIGHT WITH THE ARRIVAL/PASSAGE OF A COLD
FRONT FROM THE PLAINS. THERE IS SOME UNCERTAINTY WITH COVERAGE OF
SHRA ALONG THE FRONT BUT IT LOOKS LIKE AT THIS TIME PREVAILING
CONDITIONS SHOULD STAY VFR. SHRA WILL END OVERNIGHT AT THE WESTERN
TAF SITES IN THE WAKE OF THE FRONTAL PASSAGE. EXPECT SOME LLWS TO
DEVELOP AT THE WESTERN TAF SITES TOWARD EVENING AS WINDS DECREASE AT
THE SFC BUT STRENGTHEN JUST OFF THE SURFACE AHEAD OF THE APPROACHING
FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 606 AM EDT TUE JUL 28 2015
DEEPENING LOW PRESSURE OVER S SASKATCHEWAN THIS MORNING WILL LIFT
ACROSS MANITOBA TONIGHT...AND ACROSS ONTARIO TO HUDSON BAY WEDNESDAY
INTO WEDNESDAY NIGHT. LOOK FOR THIS LOW TO REMAIN ACROSS HUDSON BAY
THROUGH THE WEEKEND. AS A RESULT A TROUGH WILL EXTEND DOWN THROUGH
LAKE SUPERIOR TUESDAY NIGHT AND WEDNESDAY...ALONG WITH THE RETURN OF
STRONGER WINDS. S-SW WINDS AHEAD OF THE TROUGH COULD GUST NEAR 25KTS
OVER MAINLY ERN LAKE SUPERIOR TONIGHT. EXPECT SW-W GALES 35 TO 40
KNOTS OVER MAINLY WEST AND NCNTRL LAKE SUPERIOR WEDNESDAY INTO
WEDNESDAY EVENING IN THE WAKE OF THE TROUGH. AHEAD OF THE
FRONT/TROUGH PATCHY FOG WILL LINGER OVER MAINLY NORTHERN LAKE
SUPERIOR TODAY INTO TONIGHT.
THE TROUGH WILL SHIFT TO THE NEW ENGLAND STATES THURSDAY...ALLOWING
A WEAK RIDGE TO BUILD INTO THE UPPER GREAT LAKES AS WEST WINDS
SUBSIDE TO AROUND 20 KTS. IT WILL QUICKLY BE REPLACED BY A WEAK
TROUGH THURSDAY NIGHT INTO FRIDAY...ROTATING AROUND THE HUDSON BAY
LOW AS WINDS REMAIN GENERALLY BLO 20 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING FOR
LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
607 AM EDT TUE JUL 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 606 AM EDT TUE JUL 28 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER
THE NRN ROCKIES AND HIGH PLAINS AND A RIDGE FROM THE SRN PLAINS
THROUGH THE GREAT LAKES REGION INTO NRN ONTARIO. WITHIN BASE OF MID-
LEVEL TROUGH A STRONG SHORTWAVE AND DEVELOPING CLOSED LOW WAS
LIFTING NE FROM ERN MONTANA INTO THE WRN DAKOTAS. INSTABILITY
(MUCAPES 1000-2000 J/KG) AND LIFT AHEAD OF SHORTWAVE AND ALONG ASSOC
FRONTAL BOUNDARY HAS SUPPORTED A LARGE MCS OVER THE ERN DAKOTAS AND
WRN MN EARLY THIS MORNING. BY COMPARISION...HIGH PRESSURE OVER THE
GREAT LAKES REGION HAS RESULTED IN GENERALLY CLOUD FREE AND QUIET
CONDITIONS OVER UPPER MI...ALTHOUGH NIGHTTIME TEMPS HAVE BEEN QUITE
WARM... GENERALLY IN THE 60S.
MODELS INDICATE CLOUDS AND POSSIBLY A FEW SHRA FROM DIMINISHING
CONVECTION WITH MCS TO WEST COULD SPREAD INTO WRN UPPER MI THIS
AFTERNOON. DESPITE POSSIBLE INCREASE IN CLOUDS...EXPECT ENOUGH
SUNSHINE BY AFTERNOON TO PUSH TEMPS INTO THE UPPER 80S AND LOWER 90S
AS MOST LOCATIONS AGAIN TODAY. WITH DAYTIME MIXING EXPECT DEWPOINTS
TO LOWER INTO MID TO UPPER 50S AT MOST LOCATIONS WITH EVEN A FEW
LOWER 50S DEWPOINTS POSSIBLE OVER EASTERN SITES. COMBINATION OF HIGH
TEMPS AND LOWERING OF DEWPOINTS WILL RESULT IN INLAND MIN RH/S
DROPPING INTO THE 30S OVER MUCH OF CENTRAL UPPER MI WITH EVEN SOME
MID TO UPPER 20S RH/S OVER THE ERN THIRD OF UPPER MI. THIS WILL
INCREASE FIRE WEATHER CONCERNS TODAY INTO THIS EVENING GIVEN RECENT
STRETCH OF DRY WEATHER. FORTUNATELY SOUTHERLY WINDS AHEAD OF FRONT
SHOULDN/T INCREASE TOO MUCH THROUGH THIS EVENING (GENERALLY LESS
THAN 20 MPH FOR GUSTS). WEST WINDS HOWEVER COULD GET GUSTY IN WAKE
OF FRONT ON WEDNESDAY.
FOCUSING ON PCPN CHCS THIS AFTERNOON INTO TONIGHT AS FRONTAL SYSTEM
FROM PLAINS WORKS ITS WAY ACROSS THE REGION TONIGHT INTO EARLY
WEDNESDAY. MODELS SHOW SOME DIFFERENCES IN FRONTAL TIMING WITH THE
REGIONAL GEM PERHAPS A BIT QUICKER WITH FRONT INITIALLY THAN
NAM...GFS OR ECMWF MODELS. DESPITE MINOR DIFFERENCES MODELS
GENERALLY SHOW COLD FRONT REACHING INTO WRN UPPER MI THIS
EVENING...INTO CENTRAL UPPER MI AROUND 12Z WED AND EXITING ERN UPPER
MI AROUND 18Z WED. MODELS CONSISTENT WITH IDEA THAT BEST DYNAMICS
(MID-LVL Q-VECT CONV) ASSOC WITH FRONTAL SYSTEM WILL BE LIFTING WEST
AND NORTH OF THE UPPER GREAT LAKES TONIGHT...TIED TO MOVEMENT OF
SHORTWAVE AND ASSOC MID-LVL CLOSED LOW WHICH LIFT NE INTO SRN
MANITOBA AND NW ONTARIO TONIGHT. AT SAME TIME...MODELS AND SREF
ENSEMBLE FIELDS INDICATE BEST MOISTURE/INSTABILITY STAYING SOUTH OF
UPPER MI INTO WI BY TIME FRONT MOVES THROUGH TONIGHT WITH MUCAPES
500 TO MAYBE 1000 J/KG FAR WEST IN THE EVENING DECREASING TO ONLY A
FEW HUNDRED J/KG EAST OVERNIGHT. COMBINATION OF BEST DYNAMICS MOVING
WELL TO NORTH AND BEST MOISTURE STAYING SOUTH HAS LED MOST OF
MODELS TO DEPICT MORE A SCATTERED TO BROKEN LINE OF CONVECTION
DEVELOPING ALONG FRONT AS IT MOVES THROUGH UPPER MI TONIGHT. GIVEN
THE UNCERTAINTY WITH DEVELOPING CONVECTION ALONG FRONT HAVE
GENERALLY KEPT ONLY HIGH CHC POPS AND LIMITED LIKELY POPS IN FCST
FOR SCT SHRA/TSRA LATE THIS AFTERNOON/EARLY EVENING WEST SPREADING
ACROSS REST OF FCST TONIGHT.
ALSO DOWNPLAYED THREAT OF SEVERE STORMS IN HWO GIVEN LATER TIMING OF
FRONT TOWARD LATE EVENING OVERNIGHT AS INSTABILITY WILL BE WANING.
ALSO BEST DEEP SHEAR LOOKS TO LAG BEHIND THE FRONT AND OUT OF SYNC
WITH BETTER INSTABILITY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM EDT TUE JUL 28 2015
A 991MB SURFACE LOW WILL BE LIFTING NORTHEAST ALONG THE
MANITOBA/ONTARIO BORDER AT 12Z WEDNESDAY...WITH A COLD FRONT
STRETCHING SOUTH-SOUTHEAST ACROSS CENTRAL LAKE SUPERIOR AND THROUGH
CENTRAL UPPER MICHIGAN AND SOUTH THROUGH EASTERN WISCONSIN. EXPECT
A BROKEN LINE OF SHOWERS AND THUNDERSTORMS TO BE ONGOING ALONG AND
TO THE EAST OF THE COLD FRONT. WITH INSTABILITY DECREASING THROUGH
THE NIGHT...DON/T EXPECT ANY REALLY STRONG STORMS...ALTHOUGH BRIEF
PERIODS OF HEAVY RAIN IS EXPECTED. THESE SHOWERS/THUNDERSTORMS WILL
CONTINUE TO THE EAST-NORTHEAST THROUGH THE MORNING AND SHOULD LEAVE
THE CWA BY EARLY AFTERNOON (ALONG WITH THE COLD FRONT). THAT COLD
FRONT WILL BRING TEMPERATURE/HUMIDITY RELIEF TO THE REGION ON
WEDNESDAY...AS MUCH DRIER LOW LEVEL AIR MOVES OVER THE REGION AND
HIGHS ONLY RISE INTO THE UPPER 70S WEST AND LOWER 80S EAST. AFTER
CLEARING INITIALLY BEHIND THE FRONT...EXPECT SCATTERED CLOUDS TO
MOVE EAST BACK INTO THE AREA FROM LATE MORNING OVER THE WEST TO THE
AFTERNOON OVER THE CENTRAL...TIED TO 850-700MB MOISTURE ASSOCIATED
WITH THE SOUTHERN EDGE OF THE UPPER TROUGH SWEEPING EAST THROUGH THE
AREA. THE MAIN HAZARD FOR WEDNESDAY WILL BE THE GUSTY WEST-SOUTHWEST
WINDS...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN AND
LAKE SUPERIOR. MODELS STILL SHOWING A CORE OF 30-45KT 950-900MB
WINDS MOVING OVER THE AREA ON WEDNESDAY AND ASSOCIATED WITH THE
TIGHT PRESSURE GRADIENT BEHIND THE DEPARTING LOW (TIGHTEST FROM THE
KEWEENAW PENINSULA AND NORTH). WITH THE WESTERN LAKE WARMING
UP...DON/T THINK THE MARINE LAYER WILL HAVE AS MUCH OF AN AFFECT AS
EARLIER IN THE YEAR AND FEEL PRETTY COMFORTABLE IN HAVING GUSTS TO
35-40KTS OVER LSZ263-264. THUS...WILL ISSUE A GALE WATCH FOR
WEDNESDAY FOR THE WESTERN HALF OF THE LAKE. OVER THE LAND...STILL
EXPECT THE HIGHEST GUSTS TO OCCUR OVER THE KEWEENAW PENINSULA...WITH
AFTERNOON GUSTS OF 30-40MPH AND MAYBE A FEW GUSTS UP TO 45MPH AROUND
THE BROCKWAY MOUNTAIN AREA. A SECONDARY TROUGH WILL SWEEP ACROSS THE
AREA ON WEDNESDAY EVENING...SWITCHING WINDS TO THE WEST-NORTHWEST
BUT HAVING LITTLE EFFECT ON THE LOW LEVEL WINDS. THIS WILL LIKELY
KEEP SUSTAINED WINDS UP THROUGH MUCH OF THE NIGHT AND POSSIBLY KEEP
GALES GOING OVER THE NORTHERN LAKE INTO THURSDAY MORNING. WITH
LIMITED MOISTURE ASSOCIATED WITH THE FRONTAL PASSAGE...DON/T EXPECT
ANYTHING MORE THAN A FEW TO SCATTERED CLOUDS MOVING THROUGH THE AREA
ON WEDNESDAY NIGHT.
THAT WILL BE THE STORY FOR THE NEXT SEVERAL WAVES DROPPING
SOUTHEAST ACROSS THE AREA UNDER NORTHWEST FLOW ALOFT (OCCURRING
ABOUT EVERY 8-12HOURS INTO THE WEEKEND). THESE SERIES OF WAVES WILL
OCCUR ON THE SOUTH SIDE OF A THE SURFACE AND UPPER LOW MOVING
NORTHEAST ACROSS SOUTHERN HUDSON BAY. MOST WILL BE MOISTURE STARVED
AND WILL LARGELY SHOW PASSING CLOUDS WITH THEM...AND JUST SOME
SLIGHT CHANCES FOR THE THURSDAY NIGHT INTO FRIDAY PERIOD OVER THE
NORTHEAST. WINDS WILL STILL BE GUSTY ON THURSDAY...BUT GRADUALLY
DIMINISH HEADING INTO SATURDAY AS A HIGH PRESSURE RIDGE MOVES OVER
THE AREA. TEMPERATURES WILL BE NEAR NORMAL DURING THIS PERIOD AND
IN THE UPPER 70S TO LOWER 80S. MODELS STILL INDICATING THE BEST
CHANCE FOR PRECIPITATION TO OCCUR WITH ANOTHER SHORTWAVE AND
STRONGER FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING. WILL CONTINUE
TO MENTION CHANCE POPS DURING THAT PERIOD.
MODELS DIVERGE HEADING INTO NEXT WEEK ON THE TIMING OF THE UPPER
LOW SPINNING OVER HUDSON BAY DROPPING SOUTH TOWARDS THE GREAT LAKES
REGION. WHEN THIS OCCURS...IT WILL MARK A SHIFT TO BELOW NORMAL
TEMPERATURES THAT HAS BEEN SHOWN RECENTLY ON THE CFS AND LONG RANGE
ECMWF ENSEMBLES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 429 AM EDT TUE JUL 28 2015
HIGH PRESSURE WILL REMAIN IN CONTROL WITH VFR CONDITIONS EXPECTED
FOR THE ENTIRE FORECAST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 606 AM EDT TUE JUL 28 2015
DEEPENING LOW PRESSURE OVER S SASKATCHEWAN THIS MORNING WILL LIFT
ACROSS MANITOBA TONIGHT...AND ACROSS ONTARIO TO HUDSON BAY WEDNESDAY
INTO WEDNESDAY NIGHT. LOOK FOR THIS LOW TO REMAIN ACROSS HUDSON BAY
THROUGH THE WEEKEND. AS A RESULT A TROUGH WILL EXTEND DOWN THROUGH
LAKE SUPERIOR TUESDAY NIGHT AND WEDNESDAY...ALONG WITH THE RETURN OF
STRONGER WINDS. S-SW WINDS AHEAD OF THE TROUGH COULD GUST NEAR 25KTS
OVER MAINLY ERN LAKE SUPERIOR TONIGHT. EXPECT SW-W GALES 35 TO 40
KNOTS OVER MAINLY WEST AND NCNTRL LAKE SUPERIOR WEDNESDAY INTO
WEDNESDAY EVENING IN THE WAKE OF THE TROUGH. AHEAD OF THE
FRONT/TROUGH PATCHY FOG WILL LINGER OVER MAINLY NORTHERN LAKE
SUPERIOR TODAY INTO TONIGHT.
THE TROUGH WILL SHIFT TO THE NEW ENGLAND STATES THURSDAY...ALLOWING
A WEAK RIDGE TO BUILD INTO THE UPPER GREAT LAKES AS WEST WINDS
SUBSIDE TO AROUND 20 KTS. IT WILL QUICKLY BE REPLACED BY A WEAK
TROUGH THURSDAY NIGHT INTO FRIDAY...ROTATING AROUND THE HUDSON BAY
LOW AS WINDS REMAIN GENERALLY BLO 20 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING FOR
LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...07
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
429 AM EDT TUE JUL 28 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 359 PM EDT MON JUL 27 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH INTO
THE NW CONUS AND A RIDGE FROM THE SRN PLAINS THROUGH THE WRN LAKES
INTO NRN ONTARIO. AT THE SFC...SRLY WINDS PREVAILED FROM THE DAKOTAS
INTO MN BETWEEN HIGH PRES OVER THE CNTREL GREAT LAKES AND A TROUGH
OVER ERN MT/WY. ISOLD SHOWERS THAT HAD DEVELOPED ON THE LAKE
SUPERIOR BREEZE BOUNDARY FROM NEAR SAW TO ERY HAVE DISIPATED.
OTHERWISE...MOSTLY SUNNY SKIES PREAVILED WITH TEMPS INTO THE UPER
80S INLAND AND AROUND 80 ALONG THE GREAT LAKES SHORELINES.
A MID LEVEL LOW OVER MONTANA TONIGHT IS EXPECTED TO LIFT TO THE NE
INTO THE SW CORNER OF MANITOBA BY TUE EVENING. CONVECTION IS EXPECTED
TO DEVELOP OVER THE ERN DAKOTAS INTO SRN MN TONIGHT THAT MAY GENERATE
AN MCV THAT COULD SPREAD CLOUDS AND DIMINISHING SHRA/TSRA INTO WEST
UPPER MI TUE MORNING AND POSSIBLY INTO THE AFTRNOON. EVEN THOUGH THE
CLOUDS MAY HOLD DOWN HEATING EARLY...EXPECT ENOUGH SUNSHINE BY
AFTERNOON TO PUSH TEMPS INTO THE UPPER 80S. WITH DEWPOINTS IN THE
LOWER 60S WHICH HAVE TRENDED LOWER COMPARED TO PREVIOUS FCSTS
...EXPECT CAPPING WILL REMAIN STRONG ENOUGH OVER MOST OF THE CWA TO
PREVENT ANY SHRA/TSRA FROM DEVELOPING. SINCE THERE IS LINGERING
UNCERTAINTY WITH THE IMPACT OF THE CONVECTION FROM EARLIER IN THE
DAY...CONTINUED TO MENTION LOWER END CHANCE POPS OVER THE WEST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM EDT TUE JUL 28 2015
A 991MB SURFACE LOW WILL BE LIFTING NORTHEAST ALONG THE
MANITOBA/ONTARIO BORDER AT 12Z WEDNESDAY...WITH A COLD FRONT
STRETCHING SOUTH-SOUTHEAST ACROSS CENTRAL LAKE SUPERIOR AND THROUGH
CENTRAL UPPER MICHIGAN AND SOUTH THROUGH EASTERN WISCONSIN. EXPECT
A BROKEN LINE OF SHOWERS AND THUNDERSTORMS TO BE ONGOING ALONG AND
TO THE EAST OF THE COLD FRONT. WITH INSTABILITY DECREASING THROUGH
THE NIGHT...DON/T EXPECT ANY REALLY STRONG STORMS...ALTHOUGH BRIEF
PERIODS OF HEAVY RAIN IS EXPECTED. THESE SHOWERS/THUNDERSTORMS WILL
CONTINUE TO THE EAST-NORTHEAST THROUGH THE MORNING AND SHOULD LEAVE
THE CWA BY EARLY AFTERNOON (ALONG WITH THE COLD FRONT). THAT COLD
FRONT WILL BRING TEMPERATURE/HUMIDITY RELIEF TO THE REGION ON
WEDNESDAY...AS MUCH DRIER LOW LEVEL AIR MOVES OVER THE REGION AND
HIGHS ONLY RISE INTO THE UPPER 70S WEST AND LOWER 80S EAST. AFTER
CLEARING INITIALLY BEHIND THE FRONT...EXPECT SCATTERED CLOUDS TO
MOVE EAST BACK INTO THE AREA FROM LATE MORNING OVER THE WEST TO THE
AFTERNOON OVER THE CENTRAL...TIED TO 850-700MB MOISTURE ASSOCIATED
WITH THE SOUTHERN EDGE OF THE UPPER TROUGH SWEEPING EAST THROUGH THE
AREA. THE MAIN HAZARD FOR WEDNESDAY WILL BE THE GUSTY WEST-SOUTHWEST
WINDS...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN AND
LAKE SUPERIOR. MODELS STILL SHOWING A CORE OF 30-45KT 950-900MB
WINDS MOVING OVER THE AREA ON WEDNESDAY AND ASSOCIATED WITH THE
TIGHT PRESSURE GRADIENT BEHIND THE DEPARTING LOW (TIGHTEST FROM THE
KEWEENAW PENINSULA AND NORTH). WITH THE WESTERN LAKE WARMING
UP...DON/T THINK THE MARINE LAYER WILL HAVE AS MUCH OF AN AFFECT AS
EARLIER IN THE YEAR AND FEEL PRETTY COMFORTABLE IN HAVING GUSTS TO
35-40KTS OVER LSZ263-264. THUS...WILL ISSUE A GALE WATCH FOR
WEDNESDAY FOR THE WESTERN HALF OF THE LAKE. OVER THE LAND...STILL
EXPECT THE HIGHEST GUSTS TO OCCUR OVER THE KEWEENAW PENINSULA...WITH
AFTERNOON GUSTS OF 30-40MPH AND MAYBE A FEW GUSTS UP TO 45MPH AROUND
THE BROCKWAY MOUNTAIN AREA. A SECONDARY TROUGH WILL SWEEP ACROSS THE
AREA ON WEDNESDAY EVENING...SWITCHING WINDS TO THE WEST-NORTHWEST
BUT HAVING LITTLE EFFECT ON THE LOW LEVEL WINDS. THIS WILL LIKELY
KEEP SUSTAINED WINDS UP THROUGH MUCH OF THE NIGHT AND POSSIBLY KEEP
GALES GOING OVER THE NORTHERN LAKE INTO THURSDAY MORNING. WITH
LIMITED MOISTURE ASSOCIATED WITH THE FRONTAL PASSAGE...DON/T EXPECT
ANYTHING MORE THAN A FEW TO SCATTERED CLOUDS MOVING THROUGH THE AREA
ON WEDNESDAY NIGHT.
THAT WILL BE THE STORY FOR THE NEXT SEVERAL WAVES DROPPING
SOUTHEAST ACROSS THE AREA UNDER NORTHWEST FLOW ALOFT (OCCURRING
ABOUT EVERY 8-12HOURS INTO THE WEEKEND). THESE SERIES OF WAVES WILL
OCCUR ON THE SOUTH SIDE OF A THE SURFACE AND UPPER LOW MOVING
NORTHEAST ACROSS SOUTHERN HUDSON BAY. MOST WILL BE MOISTURE STARVED
AND WILL LARGELY SHOW PASSING CLOUDS WITH THEM...AND JUST SOME
SLIGHT CHANCES FOR THE THURSDAY NIGHT INTO FRIDAY PERIOD OVER THE
NORTHEAST. WINDS WILL STILL BE GUSTY ON THURSDAY...BUT GRADUALLY
DIMINISH HEADING INTO SATURDAY AS A HIGH PRESSURE RIDGE MOVES OVER
THE AREA. TEMPERATURES WILL BE NEAR NORMAL DURING THIS PERIOD AND
IN THE UPPER 70S TO LOWER 80S. MODELS STILL INDICATING THE BEST
CHANCE FOR PRECIPITATION TO OCCUR WITH ANOTHER SHORTWAVE AND
STRONGER FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING. WILL CONTINUE
TO MENTION CHANCE POPS DURING THAT PERIOD.
MODELS DIVERGE HEADING INTO NEXT WEEK ON THE TIMING OF THE UPPER
LOW SPINNING OVER HUDSON BAY DROPPING SOUTH TOWARDS THE GREAT LAKES
REGION. WHEN THIS OCCURS...IT WILL MARK A SHIFT TO BELOW NORMAL
TEMPERATURES THAT HAS BEEN SHOWN RECENTLY ON THE CFS AND LONG RANGE
ECMWF ENSEMBLES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 429 AM EDT TUE JUL 28 2015
HIGH PRESSURE WILL REMAIN IN CONTROL WITH VFR CONDITIONS EXPECTED
FOR THE ENTIRE FORECAST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EDT MON JUL 27 2015
HIGH PRESSURE OVER LOWER MI WILL KEEP A RIDGE ACROSS LAKE
SUPERIOR THROUGH EARLY TUESDAY...ALONG WITH THE POTENTIAL FOR PATCHY
FOG. DEEPENING LOW PRESSURE OVER S SASKATCHEWAN TUESDAY MORNING WILL
RACE ACROSS MANITOBA TUESDAY NIGHT...AND ACROSS ONTARIO TO HUDSON
BAY WEDNESDAY NIGHT. LOOK FOR THIS LOW TO REMAIN ACROSS HUDSON BAY
THROUGH AT LEAST FRIDAY. THE RESULT WILL BE A TROUGH EXTENDING DOWN
THROUGH LAKE SUPERIOR TUESDAY NIGHT AND WEDNESDAY...ALONG WITH THE
RETURN OF STRONGER WINDS. S-SW WINDS AHEAD OF THE TROUGH COULD GUST
NEAR 25KTS OVER MAINLY E LAKE SUPERIOR TUE NIGHT...WITH SW-W WINDS
AROUND 30KTS WEDNESDAY INTO WEDNESDAY EVENING IN THE WAKE OF THE
TROUGH. THERE MAY BE SOME GALE FORCE GUSTS BY MIDDAY WED OVER THE
WRN LAKE.
THE TROUGH WILL SHIFT TO THE NEW ENGLAND STATES
THURSDAY...ALLOWING A WEAK RIDGE TO BUILD INTO THE UPPER GREAT LAKES
THURSDAY. IT WILL QUICKLY BE REPLACED BY A WEAK TROUGH THURSDAY
NIGHT INTO FRIDAY...ROTATING AROUND THE HUDSON BAY LOW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING FOR
LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
348 AM EDT TUE JUL 28 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 359 PM EDT MON JUL 27 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH INTO
THE NW CONUS AND A RIDGE FROM THE SRN PLAINS THROUGH THE WRN LAKES
INTO NRN ONTARIO. AT THE SFC...SRLY WINDS PREVAILED FROM THE DAKOTAS
INTO MN BETWEEN HIGH PRES OVER THE CNTREL GREAT LAKES AND A TROUGH
OVER ERN MT/WY. ISOLD SHOWERS THAT HAD DEVELOPED ON THE LAKE
SUPERIOR BREEZE BOUNDARY FROM NEAR SAW TO ERY HAVE DISIPATED.
OTHERWISE...MOSTLY SUNNY SKIES PREAVILED WITH TEMPS INTO THE UPER
80S INLAND AND AROUND 80 ALONG THE GREAT LAKES SHORELINES.
A MID LEVEL LOW OVER MONTANA TONIGHT IS EXPECTED TO LIFT TO THE NE
INTO THE SW CORNER OF MANITOBA BY TUE EVENING. CONVECTION IS EXPECTED
TO DEVELOP OVER THE ERN DAKOTAS INTO SRN MN TONIGHT THAT MAY GENERATE
AN MCV THAT COULD SPREAD CLOUDS AND DIMINISHING SHRA/TSRA INTO WEST
UPPER MI TUE MORNING AND POSSIBLY INTO THE AFTRNOON. EVEN THOUGH THE
CLOUDS MAY HOLD DOWN HEATING EARLY...EXPECT ENOUGH SUNSHINE BY
AFTERNOON TO PUSH TEMPS INTO THE UPPER 80S. WITH DEWPOINTS IN THE
LOWER 60S WHICH HAVE TRENDED LOWER COMPARED TO PREVIOUS FCSTS
...EXPECT CAPPING WILL REMAIN STRONG ENOUGH OVER MOST OF THE CWA TO
PREVENT ANY SHRA/TSRA FROM DEVELOPING. SINCE THERE IS LINGERING
UNCERTAINTY WITH THE IMPACT OF THE CONVECTION FROM EARLIER IN THE
DAY...CONTINUED TO MENTION LOWER END CHANCE POPS OVER THE WEST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM EDT TUE JUL 28 2015
A 991MB SURFACE LOW WILL BE LIFTING NORTHEAST ALONG THE
MANITOBA/ONTARIO BORDER AT 12Z WEDNESDAY...WITH A COLD FRONT
STRETCHING SOUTH-SOUTHEAST ACROSS CENTRAL LAKE SUPERIOR AND THROUGH
CENTRAL UPPER MICHIGAN AND SOUTH THROUGH EASTERN WISCONSIN. EXPECT
A BROKEN LINE OF SHOWERS AND THUNDERSTORMS TO BE ONGOING ALONG AND
TO THE EAST OF THE COLD FRONT. WITH INSTABILITY DECREASING THROUGH
THE NIGHT...DON/T EXPECT ANY REALLY STRONG STORMS...ALTHOUGH BRIEF
PERIODS OF HEAVY RAIN IS EXPECTED. THESE SHOWERS/THUNDERSTORMS WILL
CONTINUE TO THE EAST-NORTHEAST THROUGH THE MORNING AND SHOULD LEAVE
THE CWA BY EARLY AFTERNOON (ALONG WITH THE COLD FRONT). THAT COLD
FRONT WILL BRING TEMPERATURE/HUMIDITY RELIEF TO THE REGION ON
WEDNESDAY...AS MUCH DRIER LOW LEVEL AIR MOVES OVER THE REGION AND
HIGHS ONLY RISE INTO THE UPPER 70S WEST AND LOWER 80S EAST. AFTER
CLEARING INITIALLY BEHIND THE FRONT...EXPECT SCATTERED CLOUDS TO
MOVE EAST BACK INTO THE AREA FROM LATE MORNING OVER THE WEST TO THE
AFTERNOON OVER THE CENTRAL...TIED TO 850-700MB MOISTURE ASSOCIATED
WITH THE SOUTHERN EDGE OF THE UPPER TROUGH SWEEPING EAST THROUGH THE
AREA. THE MAIN HAZARD FOR WEDNESDAY WILL BE THE GUSTY WEST-SOUTHWEST
WINDS...ESPECIALLY OVER THE NORTHWEST HALF OF UPPER MICHIGAN AND
LAKE SUPERIOR. MODELS STILL SHOWING A CORE OF 30-45KT 950-900MB
WINDS MOVING OVER THE AREA ON WEDNESDAY AND ASSOCIATED WITH THE
TIGHT PRESSURE GRADIENT BEHIND THE DEPARTING LOW (TIGHTEST FROM THE
KEWEENAW PENINSULA AND NORTH). WITH THE WESTERN LAKE WARMING
UP...DON/T THINK THE MARINE LAYER WILL HAVE AS MUCH OF AN AFFECT AS
EARLIER IN THE YEAR AND FEEL PRETTY COMFORTABLE IN HAVING GUSTS TO
35-40KTS OVER LSZ263-264. THUS...WILL ISSUE A GALE WATCH FOR
WEDNESDAY FOR THE WESTERN HALF OF THE LAKE. OVER THE LAND...STILL
EXPECT THE HIGHEST GUSTS TO OCCUR OVER THE KEWEENAW PENINSULA...WITH
AFTERNOON GUSTS OF 30-40MPH AND MAYBE A FEW GUSTS UP TO 45MPH AROUND
THE BROCKWAY MOUNTAIN AREA. A SECONDARY TROUGH WILL SWEEP ACROSS THE
AREA ON WEDNESDAY EVENING...SWITCHING WINDS TO THE WEST-NORTHWEST
BUT HAVING LITTLE EFFECT ON THE LOW LEVEL WINDS. THIS WILL LIKELY
KEEP SUSTAINED WINDS UP THROUGH MUCH OF THE NIGHT AND POSSIBLY KEEP
GALES GOING OVER THE NORTHERN LAKE INTO THURSDAY MORNING. WITH
LIMITED MOISTURE ASSOCIATED WITH THE FRONTAL PASSAGE...DON/T EXPECT
ANYTHING MORE THAN A FEW TO SCATTERED CLOUDS MOVING THROUGH THE AREA
ON WEDNESDAY NIGHT.
THAT WILL BE THE STORY FOR THE NEXT SEVERAL WAVES DROPPING
SOUTHEAST ACROSS THE AREA UNDER NORTHWEST FLOW ALOFT (OCCURRING
ABOUT EVERY 8-12HOURS INTO THE WEEKEND). THESE SERIES OF WAVES WILL
OCCUR ON THE SOUTH SIDE OF A THE SURFACE AND UPPER LOW MOVING
NORTHEAST ACROSS SOUTHERN HUDSON BAY. MOST WILL BE MOISTURE STARVED
AND WILL LARGELY SHOW PASSING CLOUDS WITH THEM...AND JUST SOME
SLIGHT CHANCES FOR THE THURSDAY NIGHT INTO FRIDAY PERIOD OVER THE
NORTHEAST. WINDS WILL STILL BE GUSTY ON THURSDAY...BUT GRADUALLY
DIMINISH HEADING INTO SATURDAY AS A HIGH PRESSURE RIDGE MOVES OVER
THE AREA. TEMPERATURES WILL BE NEAR NORMAL DURING THIS PERIOD AND
IN THE UPPER 70S TO LOWER 80S. MODELS STILL INDICATING THE BEST
CHANCE FOR PRECIPITATION TO OCCUR WITH ANOTHER SHORTWAVE AND
STRONGER FRONT ON SATURDAY NIGHT INTO SUNDAY MORNING. WILL CONTINUE
TO MENTION CHANCE POPS DURING THAT PERIOD.
MODELS DIVERGE HEADING INTO NEXT WEEK ON THE TIMING OF THE UPPER
LOW SPINNING OVER HUDSON BAY DROPPING SOUTH TOWARDS THE GREAT LAKES
REGION. WHEN THIS OCCURS...IT WILL MARK A SHIFT TO BELOW NORMAL
TEMPERATURES THAT HAS BEEN SHOWN RECENTLY ON THE CFS AND LONG RANGE
ECMWF ENSEMBLES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 720 PM EDT MON JUL 27 2015
HIGH PRESSURE WILL REMAIN IN CONTROL WITH VFR CONDITIONS EXPECTED
FOR THE ENTIRE FORECAST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EDT MON JUL 27 2015
HIGH PRESSURE OVER LOWER MI WILL KEEP A RIDGE ACROSS LAKE
SUPERIOR THROUGH EARLY TUESDAY...ALONG WITH THE POTENTIAL FOR PATCHY
FOG. DEEPENING LOW PRESSURE OVER S SASKATCHEWAN TUESDAY MORNING WILL
RACE ACROSS MANITOBA TUESDAY NIGHT...AND ACROSS ONTARIO TO HUDSON
BAY WEDNESDAY NIGHT. LOOK FOR THIS LOW TO REMAIN ACROSS HUDSON BAY
THROUGH AT LEAST FRIDAY. THE RESULT WILL BE A TROUGH EXTENDING DOWN
THROUGH LAKE SUPERIOR TUESDAY NIGHT AND WEDNESDAY...ALONG WITH THE
RETURN OF STRONGER WINDS. S-SW WINDS AHEAD OF THE TROUGH COULD GUST
NEAR 25KTS OVER MAINLY E LAKE SUPERIOR TUE NIGHT...WITH SW-W WINDS
AROUND 30KTS WEDNESDAY INTO WEDNESDAY EVENING IN THE WAKE OF THE
TROUGH. THERE MAY BE SOME GALE FORCE GUSTS BY MIDDAY WED OVER THE
WRN LAKE.
THE TROUGH WILL SHIFT TO THE NEW ENGLAND STATES
THURSDAY...ALLOWING A WEAK RIDGE TO BUILD INTO THE UPPER GREAT LAKES
THURSDAY. IT WILL QUICKLY BE REPLACED BY A WEAK TROUGH THURSDAY
NIGHT INTO FRIDAY...ROTATING AROUND THE HUDSON BAY LOW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
956 PM CDT WED JUL 29 2015
.UPDATE...
ISSUED AT 947 PM CDT WED JUL 29 2015
CLOUDS AND SHOWERS CONTINUE TO DECREASE AS OF MID EVENING. THE
MOST CLOUD COVER AT THIS TIME WAS ACROSS THE FAR NORTH. ZONES AND
GRIDS APPEAR TO BE IN GOOD SHAPE...AND ONLY MINOR CHANGES HAVE
BEEN MADE FOR THE EVENING UPDATE.
UPDATE ISSUED AT 702 PM CDT WED JUL 29 2015
UPDATED FOR THE 00Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 308 PM CDT WED JUL 29 2015
AN UNUSUALLY DEEP AREA OF LOW PRESSURE OVER FAR NW ONTARIO WILL
CONTINUE TO CAUSE GUSTY WESTERLY WINDS ACROSS THE NORTHLAND
THROUGH EARLY THIS EVENING. EXPECT WIDESPREAD WIND GUSTS OF 25 TO
40 MPH. THERE COULD BE STRAY GUSTS TO 45 MPH IN NE MINNESOTA LATE
THIS AFTERNOON.
MUCH OF THE FORECAST AREA HAD BKN/OVC CLOUD COVER DUE TO THE
INSTABILITY CAUSED BY THE COOL AND RELATIVELY HUMID WESTERLY
FLOW. THIS CLOUD COVER SHOULD GRADUALLY DIMINISH THIS EVENING AND
OVERNIGHT AS HEIGHTS INCREASE AS THE LOW LIFTS INTO HUDSON BAY.
SEVERAL MODELS ARE INDICATING LOW POTENTIAL FOR PCPN ACROSS THE
NORTHERN FORECAST AREA THROUGH TONIGHT...INCLUDING THE
NAM12/GEMREG/SREF/WRF. LIGHT RAIN IS POSSIBLE ACROSS THE
BORDERLAND AND ARROWHEAD THROUGH TONIGHT...WITH CHANCES GRADUALLY
DIMINISHING OVERNIGHT. DESPITE THE OVERNIGHT CLEARING...LEANED ON
THE SLIGHTLY WARMER GUIDANCE SINCE THE OVERNIGHT WINDS SHOULD HELP
BOLSTER THE TEMPERATURES.
THE NORTHLAND WILL REMAIN IN NW FLOW ALOFT ON THURSDAY. THE DAY
SHOULD BE WARMER AND SUNNIER. THE NAM12/GFS SOUNDINGS INDICATE
THE LIKELIHOOD OF WIDESPREAD 20 TO 25 MPH WIND GUSTS DURING THE
AFTERNOON AND EARLY EVENING BASED ON THE WINDS IN THE MIXING
LAYERS IN THE SOUNDINGS. THE NAM12/GFS SOUNDINGS ALSO SUGGEST THE
CONVECTIVE TEMPERATURES SHOULD BE LOW ENOUGH TO POP SCATTERED
CUMULUS BY THE AFTERNOON. SEVERAL MODELS ARE INDICATING THE
POTENTIAL FOR AFTERNOON SHOWERS AND WEAK STORMS...INCLUDING THE
NAM12/GEMREG/GFS/WRF/SREF MODELS. THIS IS MOSTLY FOR THE FAR
NORTHERN FORECAST AREA...AND NEAR AND EAST OF HIGHWAY 13 IN NW
WISCONSIN. THE NAM12/SREF ARE INDICATING THE POTENTIAL FOR UP TO
SEVERAL HUNDRED J/KG OF MIXED LAYER CAPE...SO THERE COULD BE A
STRAY STRONGER CELL. THE MORE PROMINENT SHOWERS AND STORMS COULD
END UP PRODUCING GUSTY WINDS...POTENTIALLY UP TO 40 MPH. HIGHS
SHOULD BE IN THE UPPER 70S TO LOW 80S.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 308 PM CDT WED JUL 29 2015
A FAST NW FLOW ALOFT WILL AFFECT THE FORECAST AREA THURSDAY NIGHT
THROUGH TUESDAY. IN THIS FLOW...PIECES OF SHORT WAVE ENERGY WILL
ROTATE THROUGH THE AREA FRIDAY AND SATURDAY NIGHT THROUGH TUESDAY.
WITH THESE PIECES OF ENERGY...A FEW SHOWERS AND ISOLATED
THUNDERSTORMS WILL OCCUR OVER PARTS OF THE REGION AND HAVE POPS
ALIGNED TO ACCOUNT FOR THESE IMPULSES. BETWEEN THESE SHORT
WAVES...PERIODS OF DRY WEATHER WILL BE FOUND. TEMPERATURES DURING
THIS PERIOD WILL BE NEAR NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 702 PM CDT WED JUL 29 2015
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. GUSTY WINDS
WILL DIMINISH THIS EVENING AS THE NIGHT TIME INVERSION DEVELOPS
BETWEEN 01Z TO 03Z. A BRIEF SHOWER IS POSSIBLE AT INL BETWEEN 00Z
AND 03Z DUE TO SHOWERS IN NORTHWESTERN ONTARIO. THIS IS SHOWN WELL
BY THE LAST FEW HRRR AND HRRRX RUNS...ALONG WITH CURRENT RADAR
TRENDS.
GUSTY WINDS WILL DEVELOP AGAIN AT ALL TERMINALS BETWEEN
13Z TO 15Z. DAY TIME HEATING COUPLED WITH A SHORTWAVE MOVING INTO
FAR NORTHERN MINNESOTA WILL RESULT IN A THREAT OF SHOWERS...AND
POSSIBLY A FEW THUNDERSTORMS AT HIB AND INL LATE IN THE PERIOD.
STILL UNCERTAIN ON THE EXACT LOCATION AND COVERAGE OF THIS
ACTIVITY...SO LEFT AS VCSH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 60 80 60 78 / 0 10 10 0
INL 56 78 53 76 / 40 30 10 20
BRD 59 83 59 80 / 0 0 10 0
HYR 59 80 56 77 / 0 10 10 0
ASX 62 80 59 78 / 0 20 10 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THURSDAY FOR LSZ121-140>148.
&&
$$
UPDATE...DAP
SHORT TERM...GROCHOCINSKI
LONG TERM...GSF
AVIATION...WL
AREA FORECAST DISCUSSION
NWS DULUTH MN
702 PM CDT WED JUL 29 2015
.UPDATE...
ISSUED AT 702 PM CDT WED JUL 29 2015
UPDATED FOR THE 00Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 308 PM CDT WED JUL 29 2015
AN UNUSUALLY DEEP AREA OF LOW PRESSURE OVER FAR NW ONTARIO WILL
CONTINUE TO CAUSE GUSTY WESTERLY WINDS ACROSS THE NORTHLAND
THROUGH EARLY THIS EVENING. EXPECT WIDESPREAD WIND GUSTS OF 25 TO
40 MPH. THERE COULD BE STRAY GUSTS TO 45 MPH IN NE MINNESOTA LATE
THIS AFTERNOON.
MUCH OF THE FORECAST AREA HAD BKN/OVC CLOUD COVER DUE TO THE
INSTABILITY CAUSED BY THE COOL AND RELATIVELY HUMID WESTERLY
FLOW. THIS CLOUD COVER SHOULD GRADUALLY DIMINISH THIS EVENING AND
OVERNIGHT AS HEIGHTS INCREASE AS THE LOW LIFTS INTO HUDSON BAY.
SEVERAL MODELS ARE INDICATING LOW POTENTIAL FOR PCPN ACROSS THE
NORTHERN FORECAST AREA THROUGH TONIGHT...INCLUDING THE
NAM12/GEMREG/SREF/WRF. LIGHT RAIN IS POSSIBLE ACROSS THE
BORDERLAND AND ARROWHEAD THROUGH TONIGHT...WITH CHANCES GRADUALLY
DIMINISHING OVERNIGHT. DESPITE THE OVERNIGHT CLEARING...LEANED ON
THE SLIGHTLY WARMER GUIDANCE SINCE THE OVERNIGHT WINDS SHOULD HELP
BOLSTER THE TEMPERATURES.
THE NORTHLAND WILL REMAIN IN NW FLOW ALOFT ON THURSDAY. THE DAY
SHOULD BE WARMER AND SUNNIER. THE NAM12/GFS SOUNDINGS INDICATE
THE LIKELIHOOD OF WIDESPREAD 20 TO 25 MPH WIND GUSTS DURING THE
AFTERNOON AND EARLY EVENING BASED ON THE WINDS IN THE MIXING
LAYERS IN THE SOUNDINGS. THE NAM12/GFS SOUNDINGS ALSO SUGGEST THE
CONVECTIVE TEMPERATURES SHOULD BE LOW ENOUGH TO POP SCATTERED
CUMULUS BY THE AFTERNOON. SEVERAL MODELS ARE INDICATING THE
POTENTIAL FOR AFTERNOON SHOWERS AND WEAK STORMS...INCLUDING THE
NAM12/GEMREG/GFS/WRF/SREF MODELS. THIS IS MOSTLY FOR THE FAR
NORTHERN FORECAST AREA...AND NEAR AND EAST OF HIGHWAY 13 IN NW
WISCONSIN. THE NAM12/SREF ARE INDICATING THE POTENTIAL FOR UP TO
SEVERAL HUNDRED J/KG OF MIXED LAYER CAPE...SO THERE COULD BE A
STRAY STRONGER CELL. THE MORE PROMINENT SHOWERS AND STORMS COULD
END UP PRODUCING GUSTY WINDS...POTENTIALLY UP TO 40 MPH. HIGHS
SHOULD BE IN THE UPPER 70S TO LOW 80S.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 308 PM CDT WED JUL 29 2015
A FAST NW FLOW ALOFT WILL AFFECT THE FORECAST AREA THURSDAY NIGHT
THROUGH TUESDAY. IN THIS FLOW...PIECES OF SHORT WAVE ENERGY WILL
ROTATE THROUGH THE AREA FRIDAY AND SATURDAY NIGHT THROUGH TUESDAY.
WITH THESE PIECES OF ENERGY...A FEW SHOWERS AND ISOLATED
THUNDERSTORMS WILL OCCUR OVER PARTS OF THE REGION AND HAVE POPS
ALIGNED TO ACCOUNT FOR THESE IMPULSES. BETWEEN THESE SHORT
WAVES...PERIODS OF DRY WEATHER WILL BE FOUND. TEMPERATURES DURING
THIS PERIOD WILL BE NEAR NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 702 PM CDT WED JUL 29 2015
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. GUSTY WINDS
WILL DIMINISH THIS EVENING AS THE NIGHT TIME INVERSION DEVELOPS
BETWEEN 01Z TO 03Z. A BRIEF SHOWER IS POSSIBLE AT INL BETWEEN 00Z
AND 03Z DUE TO SHOWERS IN NORTHWESTERN ONTARIO. THIS IS SHOWN WELL
BY THE LAST FEW HRRR AND HRRRX RUNS...ALONG WITH CURRENT RADAR
TRENDS.
GUSTY WINDS WILL DEVELOP AGAIN AT ALL TERMINALS BETWEEN
13Z TO 15Z. DAY TIME HEATING COUPLED WITH A SHORTWAVE MOVING INTO
FAR NORTHERN MINNESOTA WILL RESULT IN A THREAT OF SHOWERS...AND
POSSIBLY A FEW THUNDERSTORMS AT HIB AND INL LATE IN THE PERIOD.
STILL UNCERTAIN ON THE EXACT LOCATION AND COVERAGE OF THIS
ACTIVITY...SO LEFT AS VCSH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 60 80 60 78 / 0 10 10 0
INL 56 78 53 76 / 40 30 10 20
BRD 60 83 59 80 / 0 0 10 0
HYR 59 80 56 77 / 0 10 10 0
ASX 61 80 59 78 / 0 20 10 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR WIZ001.
MN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ010>012-018>021-
025-026-033>038.
LS...GALE WARNING UNTIL 7 PM CDT THIS EVENING FOR LSZ121-140>148.
&&
$$
UPDATE...WL
SHORT TERM...GROCHOCINSKI
LONG TERM...GSF
AVIATION...WL
AREA FORECAST DISCUSSION...UPDATE
NWS JACKSON MS
853 PM CDT WED JUL 29 2015
.UPDATE... ONCE AGAIN THIS AFTERNOON THE BULK OF THE SHOWERS AND
STORMS OCCURRED ACROSS EASTERN MS WHILE MANY LOCATIONS ALONG AND
WEST OF I-55 WERE SCARCELY THREATENED BY RAIN. MORE UBIQUITOUS WAS
THE HEAT...BUT WITH THE PERSISTENCE OF THE CURRENT HEAT WAVE MANY
PEOPLE ACROSS THE REGION COULD BE SOMEWHAT ACCUSTOMED TO THAT.
THE DISTURBANCE FLOWING AROUND THE EAST SIDE OF THE DASTARDLY
UPPER RIDGE HELPED FUEL THE STORMS RUNNING AMOK THROUGH THE EASTERN
HALF OF MS TODAY...BUT MOST OF THOSE STORMS ARE NOW SHIFTING DOWN
TOWARD THE COAST. A COLD FRONT SLOWLY ADVANCING DOWN TOWARD THE
REGION IS KICKING UP SOME SCATTERED STORMS RIGHT NOW ACROSS THE TN
VALLEY...AND THE LATEST HRRR SUGGESTS POTENTIAL FOR A FAIR AMOUNT OF
THIS ACTIVITY TO PIVOT SOUTH INTO AT LEAST NORTHERN ZONES LATE
TONIGHT. HOWEVER...I THINK THIS SOLUTION IS OVERLY OPTIMISTIC GIVEN
PREDOMINATE RIDGING ALOFT...ALTHOUGH I DID LEAVE SOME 20 POPS LATE
TONIGHT IN AT LEAST EASTERN MS WHERE IT IS PLAUSIBLE FESTERING
INSTABILITY AND A VERY WEAK RIDGE-ROUNDING DISTURBANCE COULD
CATALYZE INTO A SMALL BIT OF PRECIP.
THE BETTER CHANCE FOR SHOWERS AND STORMS ASSOCIATED WITH THIS
INCOMING FRONT WILL COME TOMORROW...AND THIS IS REPRESENTED WELL
IN THE CURRENT FORECAST. /BB/
&&
.AVIATION...MOSTLY VFR CONDITIONS ARE EXPECTED TONIGHT ALTHOUGH NEAR-
DAWN BRIEF MVFR CATS OR A LATE NIGHT SHOWER CANNOT BE RULED OUT AT
GWO/CBM/GTR/NMM/MEI/PIB/HBG. TOMORROW CHANCES FOR SHOWERS AND STORMS
WILL INCREASE BY MIDDAY...ESPECIALLY ACROSS EASTERN MS AND SOUTH OF
I-20. WINDS TOMORROW WILL BE FROM THE NORTH AND PERHAPS EVEN A
LITTLE GUSTY...ESPECIALLY UP AROUND THE HIGHWAY 82 CORRIDOR. /BB/
&&
.PREV DISCUSSION... /ISSUED 332 PM CDT WED JUL 29 2015/
SHORT TERM...TONIGHT THROUGH FRIDAY...UPPER RIDGING CONTINUES TO
PREVAIL ACROSS THE ARKLAMISS WITH ANOTHER DAY OF HOT TEMPERATURES.
MOISTURE HAS INCREASED SIGNIFICANTLY WITH GREATER THAN 2.0 INCHES
ACROSS MOST OF THE AREA. WITH PLENTY OF MOISTURE ACROSS THE AREA
ALONG WITH SHORT WAVE ENERGY MOVING FROM NORTH TO SOUTH...SHOWERS AND
THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE ACROSS THE AREA TONIGHT
INTO THURSDAY MORNING.
A SURFACE BOUNDARY WILL BEGIN TO DROP SOUTH ACROSS THE AREA ON
THURSDAY AND THIS WILL BRING ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS. THIS WILL BE A WELCOME RELIEF TO THE HEAT WE HAVE BEEN
EXPERIENCING FOR QUITE SOME TIME. THE FLY IN THE OINTMENT WILL BE
THAT TEMPERATURES OUT AHEAD OF THE BOUNDARY WILL ONCE AGAIN BE
HOT...WITH HEAT INDICES CLIMBING FROM 106-110 ACROSS MUCH OF THE
AREA THURSDAY AFTERNOON. IN THE WAKE OF THE BOUNDARY SLIGHTLY COOLER
AND MUCH DRIER AIR WILL BEGIN TO SPREAD SOUTH ACROSS THE NORTHERN
PORTIONS OF THE AREA LATE THURSDAY AFTERNOON AND BUILD SOUTH THROUGH
FRIDAY. MOISTURE WILL CONTINUE TO BE PLENTIFUL ON THURSDAY WITH PWATS
UP CLOSE TO 2.0 INCHES THROUGH MOST OF THE DAY. AFTERNOON SHOWERS AND
THUNDERSTORMS WILL DEVELOP ONCE AGAIN AND WITH SUFFICIENT INSTABILITY
SOME OF THE STORMS COULD BE STRONG TO SEVERE. WILL INTRODUCE A
LIMITED AREA FOR SEVERE FOR AREAS GENERALLY SOUTH OF THE HIGHWAY 82
CORRIDOR.
THE BOUNDARY WILL WORK ITS WAY SOUTH ACROSS THE AREA THURSDAY NIGHT
..USHERING SOME DRIER AIR AND COOLER TEMPERATURES FOR THE WEEKEND.
OVERNIGHT LOWS THURSDAY NIGHT WILL FALL INTO THE UPPER 60S FOR MUCH
OF THE AREA. DRIER AIR WILL BE IN PLACE ON FRIDAY WITH PWATS
FALLING TO AROUND 1.0-1.2 INCHES ACROSS MOST OF THE AREA. A COUPLE
OF SHOWERS OR THUNDERSTORMS WILL BE POSSIBLE OVER THE SOUTHEAST
FRIDAY AFTERNOON...BUT MOST OF THE AREA WILL BE RAIN FREE.
TEMPERATURES WILL BE A LITTLE COOLER WITH HIGHS IN THE LOW TO MID
90S. /15/
LONG TERM...LONG TERM (FRIDAY THROUGH NEXT WEDNESDAY)...GLOBAL MODELS
CONTINUE TO OFFER A STEADY SOLUTION FOR THE MED RANGE/LONG TERM. BY
FRI...THE PATTERN WILL HAVE ADJUSTED SOME WITH THE LARGE UPPER RIDGE
CENTERED TO OUR WEST AND OUR CWA WILL BE SITUATED MORE ON THE EASTERN
PERIPHERY. WHAT HAS BEEN TALKED ABOUT IN THE PREV DAYS FORECASTS IS A
WEAK SFC FRONT PUSHING WELL INTO THE CWA BY FRI AND BRINGING DRIER
AIR TO THE REGION REMAINS ON TRACK. THE RESULT WILL BE LOWER HUMIDITY
FRI-MON WITH SOME COOLER OVERNIGHT LOWS (UPPER 60S FOR N HALF). THE
DEEP DRY AIR WILL LIMIT PRECIP POTENTIAL AND ONLY LOW END CHANCES
10-20% ARE BEING ADVERTISED OVER THE FAR SE. WITH RELIEF FROM THE
HUMIDITY...ONE MIGHT THINK TEMPS WILL BE COOLER. THIS WILL NOT BE THE
CASE. INITIALLY HIGHS MAY BE 2-3 LESS THAN WHAT WE HAVE BEEN
SEEING...BUT MID 90S ARE EXPECTED WITH A TREND BACK TOWARD MORE UPPER
90S FOR THE TUE-WED TIMEFRAME. FIRE WEATHER CONCERNS MAY ARISE DUE TO
THE LOWER RH VALUES...THIS IS SOMETHING THAT WILL HAVE TO BE
MONITORED. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 76 97 75 94 / 14 47 14 6
MERIDIAN 72 96 73 92 / 16 57 25 13
VICKSBURG 75 99 73 95 / 12 39 12 4
HATTIESBURG 74 97 76 94 / 15 62 41 26
NATCHEZ 76 98 74 93 / 16 46 22 12
GREENVILLE 78 96 71 93 / 14 19 7 0
GREENWOOD 76 96 70 93 / 17 21 8 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY UNTIL 7 PM CDT THURSDAY FOR MSZ034>066-072>074.
LA...HEAT ADVISORY UNTIL 7 PM CDT THURSDAY FOR LAZ007>009-015-016-
023>026.
AR...HEAT ADVISORY UNTIL 7 PM CDT THURSDAY FOR ARZ074-075.
&&
$$
BB/15/CME
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
608 PM CDT WED JUL 29 2015
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 249 PM CDT WED JUL 29 2015
FORECAST CONCERNS IN THE VERY SHORT TERM WILL BE ANY LIGHT
SPRINKLES IN SOUTHEAST NEBRASKA...THEN TEMPERATURES...AND CHANCE
OF THUNDERSTORMS FRIDAY INTO SATURDAY.
WATER VAPOR SATELLITE IMAGERY SHOWED THE MAIN SYNOPTIC FEATURE OF
INTEREST WAS THE CLOSED LOW PRESSURE CENTER OVER ONTARIO CANADA
WITH THE MID LEVEL MOISTURE PLUME FROM THE BAJA OF CALIFORNIA
THROUGH THE FOUR CORNERS REGION INTO THE CENTRAL PLAINS AND OHIO
RIVER VALLEY. OF NOTE ON THE H3 MAP WAS THE H3 JET OVER THE
NORTHERN/CENTRAL PLAINS INTO THE GREAT LAKES. AT H5...THE
STRONGEST HEIGHT FALLS WERE ASSOCIATED WITH THE CLOSED LOW IN
CANADA AND THESE TRAILED SOUTHWARD INTO THE PLAINS. MID LEVEL
MOISTURE WAS NOTED AT H5 AT KLBF ON THEIR 12Z SOUNDING. THE BETTER
H7 AND H85 MOISTURE WAS SUPPRESSED TO THE SOUTH ACROSS KANSAS.H85
DEWPOINTS OF 14-16 DEG C FROM NEW MEXICO INTO TX/OK/SOUTHERN KS.
THERE IS A POCKET OF WEAK WARM AIR ADVECTION/WEAKENING H85-H7
FRONTOGENESIS WITH PATCHY MID LEVEL CUMULUS AND A FEW
SPRINKLES. ALSO HAVE SOME WEAK RIGHT ENTRANCE JET LIFT. HAVE
ADDED SOME SPRINKLES WITH THESE FEATURES. MOST OF THE MODELS WERE
DRY...HOWEVER THE HRRR AND THE HRRRX DID HINT AT THIS IN THEIR
ASSIMILATED REFLECTIVITY FIELDS. SURFACE HIGH PRESSURE PREVAILS
FOR THE REST OF TONIGHT INTO THURSDAY. LOWS TONIGHT IN THE UPPER
50S TO LOWER 60S. HIGH THURSDAY SHOULD TOP OUT IN THE UPPER 80S TO
LOWER 90S.
DEEPER MOISTURE RETURNS THURSDAY NIGHT AND FRIDAY WITH A WEST TO
EAST INSTABILITY AXIS DEVELOPING AND MOISTURE POOLING ALONG THIS
AXIS. WE ARE IN NORTHWEST LOW ALOFT AND THE FORCING IS WEAK.
INSTABILITY DOES INCREASE TO 2000 J/KG THURSDAY NIGHT AND 4000
J/KG FRIDAY. DO MENTION ISOLATED TO SCATTERED THUNDERSTORMS
FRIDAY AND SATURDAY WITH WEAK FORCING IN THIS PATTERN. HIGH
TEMPERATURES CONTINUE IN THE MID TO UPPER 80S EACH DAY.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 249 PM CDT WED JUL 29 2015
THE UNSETTLED PATTERN CONTINUES IN THE EXTENDED AS RIDGE AMPLIFIES
TO THE WEST WITH THE MID TROPOSPHERIC TROF TO OUR EAST AND WE
REMAIN IN NORTHWEST FLOW ALOFT. THE EC TRIES TO BRING A DEEPER
WAVE ACROSS THE ROCKIES INTO THE PLAINS MONDAY NIGHT AND TUESDAY
WITH MORE ROBUST PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 554 PM CDT WED JUL 29 2015
VFR CONDITIONS EXPECTED THROUGH THE TAF CYCLE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1235 PM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 245 AM CDT TUE JUL 28 2015
LINE OF CONVECTION EXTENDED FROM EASTERN SOUTH DAKOTA INTO NORTH
CENTRAL NEBRASKA AT 07Z WITH ADDITIONAL DEVELOPMENT STARTING ALONG
THE NORTHWEST IOWA BORDER. COLD FRONT LAGGED THE CONVECTION
EXTENDING FROM CENTRAL SOUTH DAKOTA INTO WESTERN NEBRASKA.
MAIN QUESTION FOR NOW IS HOW LONG THIS COMPLEX HOLDS TOGETHER AS
IT MOVES INTO AREA OF WEAKER INSTABILITY ACROSS EASTERN NEBRASKA.
EXPECT SOME CHANCE OF THUNDERSTORMS IN ADVANCE OF THE FRONT TODAY
ALTHOUGH BECOMING MORE ISOLATED THROUGH THE MORNING AS LOW LEVEL
FLOW WEAKENS AND BECOMES SOUTHWESTERLY...BEFORE INCREASING IN
COVERAGE AGAIN IN THE AFTERNOON. LATEST RAP MOVES FRONT INTO
NORTHEAST NEBRASKA AROUND 13Z THEN REACHES FAR SOUTHEAST PART OF
THE CWA BY 23Z. RAIN COULD JUMP PARTS OF THE AREA TODAY BEFORE THE
CHANCE INCREASES AGAIN LATER THIS AFTERNOON AND TONIGHT EAST AND
SOUTH OF THE AREA WHERE BETTER INSTABILITY IN PLACE.
HOT AND HUMID TODAY IN SOUTHEAST AREAS WHERE FRONT COMES THROUGH
LATE IN THE AFTERNOON OR EARLY EVENING. COOLER AND LESS HUMID AIR
BEHIND THE FRONT TONIGHT AND WEDNESDAY BEFORE A RETURN TO WARMER
TEMPS ON THURSDAY AS SOUTHERLY FLOW RETURNS.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 AM CDT TUE JUL 28 2015
EXTENDED MODELS CONTINUE TO HOLD UPPER HIGH CENTER OVER THE
SOUTHWEST CONUS DURING THE PERIOD WITH SOME DIFFERENCE IN
AMPLITUDE OF THE PATTERN. GFS INDICATES MORE AMPLITUDE IN ITS
SOLUTION WITH EURO SHOWING A FLATTER FLOW ACROSS THE TOP OF THE
RIDGE. LATEST GUIDANCE SUGGESTS SEASONAL TEMPERATURES THROUGH THE
WEEKEND THEN SOMEWHAT COOLER FOR EARLY NEXT WEEK. BEST CHANCE OF
PRECIP COMES AROUND SUNDAY WHEN NEXT FRONT MOVES INTO THE AREA
WITH GFS SHOWING STRONGER COOLING WITH ITS MORE AMPLIFIED FLOW.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1232 PM CDT TUE JUL 28 2015
COLD FRONT IS BRINGING A WIND SHIFT TO THE TAF SITES...AS WELL AS
A CHANCE OF SHOWERS/STORMS AT KOMA/KLNK THIS AFTERNOON. FRONT IS
THROUGH KOFK...WITH NORTHWEST WINDS THAT WILL SLACKEN TONIGHT.
SHOWERS/STORMS SHOULD MOVE/EXPAND INTO THE VICINITY OF KOMA AND
KLNK LATER THIS AFTERNOON. STILL A LITTLE LOW ON CONFIDENCE OF
COVERAGE...BUT TOOK A BEST SHOT OF WHEN SHOWERS/STORMS WOULD
AFFECT EACH SITE. AS THE FRONT MOVES THROUGH...WINDS WILL TURN TO
NORTHWEST AT KOMA/KLNK AND CHANCE OF SHOWERS/STORMS WILL SHIFT TO
THE SOUTH AND AWAY FROM TAF SITES...LEAVING VFR CONDITIONS FOR THE
REST OF THE TAF CYCLE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...MAYES
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
613 AM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 245 AM CDT TUE JUL 28 2015
LINE OF CONVECTION EXTENDED FROM EASTERN SOUTH DAKOTA INTO NORTH
CENTRAL NEBRASKA AT 07Z WITH ADDITIONAL DEVELOPMENT STARTING ALONG
THE NORTHWEST IOWA BORDER. COLD FRONT LAGGED THE CONVECTION
EXTENDING FROM CENTRAL SOUTH DAKOTA INTO WESTERN NEBRASKA.
MAIN QUESTION FOR NOW IS HOW LONG THIS COMPLEX HOLDS TOGETHER AS
IT MOVES INTO AREA OF WEAKER INSTABILITY ACROSS EASTERN NEBRASKA.
EXPECT SOME CHANCE OF THUNDERSTORMS IN ADVANCE OF THE FRONT TODAY
ALTHOUGH BECOMING MORE ISOLATED THROUGH THE MORNING AS LOW LEVEL
FLOW WEAKENS AND BECOMES SOUTHWESTERLY...BEFORE INCREASING IN
COVERAGE AGAIN IN THE AFTERNOON. LATEST RAP MOVES FRONT INTO
NORTHEAST NEBRASKA AROUND 13Z THEN REACHES FAR SOUTHEAST PART OF
THE CWA BY 23Z. RAIN COULD JUMP PARTS OF THE AREA TODAY BEFORE THE
CHANCE INCREASES AGAIN LATER THIS AFTERNOON AND TONIGHT EAST AND
SOUTH OF THE AREA WHERE BETTER INSTABILITY IN PLACE.
HOT AND HUMID TODAY IN SOUTHEAST AREAS WHERE FRONT COMES THROUGH
LATE IN THE AFTERNOON OR EARLY EVENING. COOLER AND LESS HUMID AIR
BEHIND THE FRONT TONIGHT AND WEDNESDAY BEFORE A RETURN TO WARMER
TEMPS ON THURSDAY AS SOUTHERLY FLOW RETURNS.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 AM CDT TUE JUL 28 2015
EXTENDED MODELS CONTINUE TO HOLD UPPER HIGH CENTER OVER THE
SOUTHWEST CONUS DURING THE PERIOD WITH SOME DIFFERENCE IN
AMPLITUDE OF THE PATTERN. GFS INDICATES MORE AMPLITUDE IN ITS
SOLUTION WITH EURO SHOWING A FLATTER FLOW ACROSS THE TOP OF THE
RIDGE. LATEST GUIDANCE SUGGESTS SEASONAL TEMPERATURES THROUGH THE
WEEKEND THEN SOMEWHAT COOLER FOR EARLY NEXT WEEK. BEST CHANCE OF
PRECIP COMES AROUND SUNDAY WHEN NEXT FRONT MOVES INTO THE AREA
WITH GFS SHOWING STRONGER COOLING WITH ITS MORE AMPLIFIED FLOW.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 615 AM CDT TUE JUL 28 2015
SCATTERED TSRA CONTINUE MAINLY FROM NORTH OF KOMA TO NORTHWEST OF
KLNK. ACTIVITY MAY HANG AROUND INTO MID MORNING BEFORE WEAKENING
AND SOME MVFR CONDITIONS WILL BE POSSIBLE. THE QUESTION THEN
BECOMES HOW MUCH ADDITIONAL ACTIVITY WILL DEVELOP LATER AS THE
COLD FRONT APPROACHES. UNCERTAINTY IS TOO HIGH TO INCLUDE TSRA FOR
LATE AFTERNOON SO WILL JUST HAVE A PROB GROUP FOR -SHRA. FORECASTS
WILL NEED ADJUSTMENT LATER AS THINGS EVOLVE. WINDS WILL SHIFT TO
NORTHWEST AT KOFK BY AROUND MID DAY AND THEN FOR KOMA AND KLNK BY
EVENING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
300 AM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 245 AM CDT TUE JUL 28 2015
LINE OF CONVECTION EXTENDED FROM EASTERN SOUTH DAKOTA INTO NORTH
CENTRAL NEBRASKA AT 07Z WITH ADDITIONAL DEVELOPMENT STARTING ALONG
THE NORTHWEST IOWA BORDER. COLD FRONT LAGGED THE CONVECTION
EXTENDING FROM CENTRAL SOUTH DAKOTA INTO WESTERN NEBRASKA.
MAIN QUESTION FOR NOW IS HOW LONG THIS COMPLEX HOLDS TOGETHER AS
IT MOVES INTO AREA OF WEAKER INSTABILITY ACROSS EASTERN NEBRASKA.
EXPECT SOME CHANCE OF THUNDERSTORMS IN ADVANCE OF THE FRONT TODAY
ALTHOUGH BECOMING MORE ISOLATED THROUGH THE MORNING AS LOW LEVEL
FLOW WEAKENS AND BECOMES SOUTHWESTERLY...BEFORE INCREASING IN
COVERAGE AGAIN IN THE AFTERNOON. LATEST RAP MOVES FRONT INTO
NORTHEAST NEBRASKA AROUND 13Z THEN REACHES FAR SOUTHEAST PART OF
THE CWA BY 23Z. RAIN COULD JUMP PARTS OF THE AREA TODAY BEFORE THE
CHANCE INCREASES AGAIN LATER THIS AFTERNOON AND TONIGHT EAST AND
SOUTH OF THE AREA WHERE BETTER INSTABILITY IN PLACE.
HOT AND HUMID TODAY IN SOUTHEAST AREAS WHERE FRONT COMES THROUGH
LATE IN THE AFTERNOON OR EARLY EVENING. COOLER AND LESS HUMID AIR
BEHIND THE FRONT TONIGHT AND WEDNESDAY BEFORE A RETURN TO WARMER
TEMPS ON THURSDAY AS SOUTHERLY FLOW RETURNS.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 245 AM CDT TUE JUL 28 2015
EXTENDED MODELS CONTINUE TO HOLD UPPER HIGH CENTER OVER THE
SOUTHWEST CONUS DURING THE PERIOD WITH SOME DIFFERENCE IN
AMPLITUDE OF THE PATTERN. GFS INDICATES MORE AMPLITUDE IN ITS
SOLUTION WITH EURO SHOWING A FLATTER FLOW ACROSS THE TOP OF THE
RIDGE. LATEST GUIDANCE SUGGESTS SEASONAL TEMPERATURES THROUGH THE
WEEKEND THEN SOMEWHAT COOLER FOR EARLY NEXT WEEK. BEST CHANCE OF
PRECIP COMES AROUND SUNDAY WHEN NEXT FRONT MOVES INTO THE AREA
WITH GFS SHOWINFG STRONGER COOLING WITH ITS MORE AMPLIFIED FLOW.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1138 PM CDT MON JUL 27 2015
AN AREA OF THUNDERSTORMS IS EXPECTED TO DRIFT SOUTHEAST THROUGH
THE OVERNIGHT AND EARLY MORNING HOURS AFFECTING ALL TAF SITES
THROUGH THE MORNING. DID PUSH BACK THE TIMING AS ALL MODEL
GUIDANCE IS HINTING AT SLOWER PROGRESSION. THERE ARE A FEW MVFR
CIGS AROUND THE AREA BUT NOT WIDESPREAD AT ISSUANCE TIME. SURFACE
COLD FRONT DROPS THROUGH THE REGION TUESDAY MORNING/AFTERNOON
TURNING SOUTHERLY WINDS AROUND TO THE NORTHWEST. STRONG
THUNDERSTORMS COULD FORM ALONG THE COLD FRONT AFTER 20-22Z...WHICH
COULD BE IN CLOSE PROXIMITY TO KOMA AND KLNK. DID ADD A PROB30
GROUP TO ACCOUNT FOR THIS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1139 PM CDT MON JUL 27 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 330 PM CDT MON JUL 27 2015
PRIMARY FORECAST CONCERN IN THE SHORT TERM DEALS WITH CONVECTIVE
CHANCES LATE THIS AFTERNOON INTO THE OVERNIGHT. A SECONDARY CONCERN
IS THE PASSAGE OF A COLD FRONT...WHICH WILL PROVIDE FOR COOLER...AND
DRIER CONDITIONS.
FORECAST CONFIDENCE WITH THE CONVECTIVE CHANCES ARE NOT AS HIGH AS
ONE WOULD HOPE...ESPECIALLY GIVEN THE RECENT PERFORMANCE OF THE
SHORT TERM MODELS. THAT BEING SAID...THE 12Z NAM WITH SUPPORT FROM
THE LATEST RAP AND SEVERAL RUNS OF THE HRRR INDICATE TWO FAVORED
AREAS FOR DEVELOPMENT LATE THIS AFTERNOON AND EARLY EVENING. THE
FIRST IS ALONG A DRYLINE PUSH ACROSS NORTHEAST COLORADO. CURIOUS
HOWEVER AS TO WHY THE MODEL IS SO AMBITIOUS WITH THE NORTHEASTWARD
EXTEND OF INITIAL CONVECTION INTO SOUTHWEST NEBRASKA...BUT ON
FURTHER INVESTIGATION...THE MODEL SEEMS TO BE KEYING ON A SOUTHWEST
TO NORTHEAST LINE OF H7 FRONTOGENESIS EXTENDING INTO THE AREA.
REGARDLESS THE LATEST MESOSCALE ANALYSIS SHOWS AN ENHANCED AREA OF
DEEP LAYER MOISTURE CONVERGENCE ACROSS NORTHWEST KANSAS YIELDING
SUPPORT TO THE CONVECTIVE INITIATION IN THE VICINITY OF THE TRI-
STATE REGION. INSTABILITY IN THIS AREA IS SIGNIFICANT...BUT DEEP
LAYER SHEAR IS LACKING. STORMS MAY HAVE TROUBLE INITIALLY...BUT AS
A LLJ STRENGTHENS...CELLS SHOULD GROW UPSCALE INTO A EAST NORTHEAST
PROPAGATING MCS. AM CONCERNED WITH THE HEAVY RAIN THREAT AT THIS
POINT AS BUFR SOUNDINGS SHOW NEAR RECORD PWATS AT KLBF BEFORE STORM
INITIATION...AND STORM MOTIONS OF 15KTS OR SO. IF THE CONVECTIVE
COMPLEX MATERIALIZES LATE EVENING TO OVERNIGHT...VERY HEAVY RAINFALL
IS POSSIBLE ACROSS OUR SOUTH AS WARM CLOUD DEPTHS INCREASE OVER 11K
FEET.
THE SECOND AREA OF CONVECTIVE DEVELOPMENT APPEARS TO BE JUST
UNDERWAY ACROSS FAR EASTERN WYOMING AND WESTERN NEBRASKA AS THE DRY
LINE/THETA GRADIENT MIXES EAST. HOWEVER THE MODELS SEEM TO HAVE
STRUGGLED WITH THE AMOUNT OF MIXING TODAY...AND GIVEN NO OTHER
DISCERNABLE FEATURES OF LOW-LEVEL CONVERGENCE AT THIS
TIME...CONVECTIVE CHANCES ACROSS THE SANDHILLS LATE AFTERNOON ARE IN
QUESTION. THE HRRR CONTINUES TO BE FIXED ON A SOLUTION HOWEVER OF
CONVECTIVE CLUSTER/S/ SPREADING EAST WITH TIME ACROSS MUCH OF THE
SANDHILLS AND NORTHERN NEBRASKA. THE HRRR PICKED UP ON THIS
SOLUTION EARLY...AND DID WELL WITH LAST NIGHTS CONVECTION...SO WILL
HEAVILY CONSIDER THE GUIDANCE FOR THIS EVENING. EFFECTIVE BULK
SHEAR IS LACKING AS OF NOW ACROSS THE SANDHILLS...BUT SLOWLY
INCREASES OVER THE NEXT 6 HOURS...WITH SIGNIFICANT CAPE IN PLACE.
LARGE HAIL AND GUSTY WIND WILL ALSO BE POSSIBLE WITH THESE
CONVECTIVE STORMS.
COLD FRONT ARRIVES DRY ASSUMING THE CONVECTION PLAYS OUT AS
INDICATED ABOVE...STABLE AND COOLER CONDITIONS WILL FOLLOW FOR
TUESDAY. WILL NEED TO MONITOR RH VALUES DURING PEAK HEATING ON
TUESDAY ACROSS ZONES 204 AND 210...AS READINGS ARE SHOWN TO FALL
BELOW 20 PERCENT. FUELS HOWEVER ARE NOT SUSCEPTIBLE TO LARGE FIRE
GROWTH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 PM CDT MON JUL 27 2015
TUESDAY NIGHT...AS SURFACE HIGH PRESSURE BUILDS INTO WESTERN
NEBRASKA...CLEAR SKIES...LOWER SURFACE DEWPOINTS IN THE LOW TO MID
40S WILL RESULT IN A RELATIVELY COOL NIGHT. LOWS FROM THE UPPER
40S ERN PNHDL WITH LOWER TO MID 50S MUCH OF WESTERN NEBRASKA.
DRY CONDITIONS EXPECTED WEDNESDAY AND WEDNESDAY NIGHT WITH SURFACE
HIGH PRESSURE AND A DRIER AIRMASS IN PLACE. WITH DEWPOINTS
WEDNESDAY ONLY IN THE MID TO UPPER 40S AND HIGHS AROUND 85...THIS
WILL RESULT IN AFTERNOON RELATIVE HUMIDITY FALLING TO ABOUT 25
PERCENT.
MOISTURE WILL RETURN TO THE CENTRAL HIGH PLAINS INCLUDING WRN NEBR
ON THURSDAY. BY AFTERNOON...ISOLATED TSTMS ARE POSSIBLE MAINLY
WEST OF VALENTINE THROUGH NORTH PLATTE THEN LINGER INTO THURSDAY
NIGHT ACROSS THE SRN HALF OF THE FA.
ISOLATED TO SCATTERED THUNDERSTORMS POSSIBLE FRIDAY THROUGH
MONDAY WITH NWRLY FLOW PERSISTING ALOFT. LOW LEVEL MOISTURE IS
FORECAST TO RESIDE ACROSS THE AREA ONCE AGAIN.
TEMPERATURES WILL RANGE FROM NEAR 90 THURSDAY THEN UPPER 80S TO
LOWER 90S FRIDAY THROUGH MONDAY. MEDIUM RANGE MODELS AGREE ON A
HUDSON BAY LOW PERSISTING WITH AN UPPER RIDGE REMAINING ACROSS THE
DESERT SOUTHWEST. THIS WOULD BRING THE POTENTIAL FOR BELOW NORMAL
TEMPERATURES TO THE GREAT LAKES REGION...WHILE NORMAL TEMPERATURES
WOULD RESIDE ACROSS THE CENTRAL PLAINS INCLUDING WESTERN NEBRASKA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1132 PM CDT MON JUL 27 2015
A LINE OF THUNDERSTORMS IS MOVING EAST ALONG A COLD FRONT ACROSS
PORTIONS OF WESTERN AND NORTH CENTRAL NEBRASKA LATE THIS
EVENING. THESE STORMS ARE LOCATED IN BETWEEN VTN AND LBF...AND
CONFIDENCE IS LOW THAT THEY WILL IMPACT EITHER ONE OF THE TAF
SITES. SO HAVE NOT INCLUDED ANY MENTION FOR TSTMS AT THE
TERMINALS...BUT CANNOT COMPLETELY RULE OUT. OTHERWISE WINDS WILL
SHIFT TO THE NORTHWEST AS A COLD FRONT MOVES ACROSS THE
AREA...WITH LOCAL GUSTS APPROACHING 30 KTS AT SOME LOCATIONS
DURING THE DAY TUESDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JACOBS
LONG TERM...ROBERG
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
944 PM EDT WED JUL 29 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION LATE TONIGHT INTO
TOMORROW MORNING BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS
ACROSS THE REGION. FRIDAY IS EXPECTED TO BE SLIGHTLY COOLER AND
DRIER.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
940 PM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MADE MINOR
OVERNIGHT TEMPERATURE ADJUSTMENTS. SFC COLD FRONT CURRENTLY
BETWEEN DETROIT AND CLEVELAND WITH WEAK CONVECTION OVER EASTERN
OHIO. LATEST HRRR INDICATES CONVECTION ASSOCIATED WITH THIS
BOUNDARY WILL MOVE INTO THE WESTERN CWA AROUND 12Z THEN REACH THE
CENTRAL PTN OF THE FA INCLUDING BGM AROUND 15Z, THIS TIMING
MATCHES WELL WITH CURRENT POP FORECAST.
300 PM EDT UPDATE...
ANOTHER NICE SUMMER DAY IS PRESENT OVER CENTRAL NY AND NORTHEAST PA
THIS AFTERNOON. CIRRUS CLOUDS ARE OVERSPREADING THE REGION AS
MOISTURE IS ROUNDING THE OUTER EDGE OF THE UPPR RIDGE. A CU MID LVL
DECK IS DEVELOPING AS WELL DUE TO DIURNAL HEATING AND SOME LINGERING
MOISTURE. 850MB TEMPS WILL RISE TO NEAR 20 DEGREES C... WHICH SHOULD
RESULT TEMPS REACHING THE UPPR 80S TO LOW 90S WITH NO PROBLEM.
CLOUD COVERAGE WILL INCREASE OVERNIGHT WITH THE APPROACHING UPPR LVL
TROUGH AS IT ADVECTS MORE MOISTURE INTO THE REGION. THE WAA WILL
KEEP TEMPS WELL ABOVE SEASONAL AVERAGE IN THE 70S OVERNIGHT.
THE MENTIONED UPPR LVL TROUGH WILL BRING A COLD FRONT ACROSS THE
REGION STARTING LATE TONIGHT/NEAR SUNRISE TIME FRAME. THIS FRONT IS
FAIRLY WEAK AS VERY LITTLE CHANGES IN THE 1000-500MB HEIGHT
THICKNESS WILL OCCUR. PWAT VALUES WILL BE FAIRLY HEIGHT TOMORROW...
NEAR 2 INCHES. WITH THIS ENVIRONMENT... EXPECT SOME HEAVY RAIN
SHOWERS AS THIS FRONT PASSES. EMBEDDED THUNDER WILL BE POSSIBLE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
300 PM EDT UPDATE...
THE COLD FRONT IS EXPECTED TO MOVE EAST AND REACH I-81 ROUGHLY
AROUND 18Z TOMORROW... THEN BE EAST OUT OF THE REGION BY 00Z FRIDAY.
SHOWERS AND THUNDERSTORMS ARE LIKELY ALONG AND AHEAD OF THE COLD
FRONT. DEPENDING ON HOW QUICKLY THE FRONT MOVES THROUGH THE CWA WILL
DEPEND ON HOW STRONG THUNDERSTORMS MAY BECOME. THE SLOWER THE FRONT
MOVES THROUGH THE AREA THE MORE UNSTABLE THE ATMOSPHERE WILL BE ABLE
TO BECOME. SBCAPE AT BEST MAY BE AROUND 1800 J/KG... LOW LVL LAPSE
RATES WILL BE ROUGHLY 6.5 C/KM... MID LVL LAPSE RATES WILL BE ON THE
WEAK SIDE NEAR 5 C/KM... AND 0-6-KM BULK SHEAR VALUES WILL BE ON THE
LOW SIDE RANGING 15-25 KNOTS. PWAT VALUES WILL BE HIGH... AROUND 2
INCHES. FROM THE STATED PARAMETERS ABOVE... EXPECT MOSTLY HEAVY
SHOWERS AND THUNDERSTORMS TO DEVELOP TOMORROW AFTERNOON. A FEW
THUNDERSTORMS MAY BE ABLE TO PRODUCE A FEW GUSTY WINDS... BUT HEAVY
RAIN IS EXPECTED TO BE THE MAIN THREAT.
BEHIND THE FROPA EXPECT CLOUD COVERAGE TO DISSIPATE FAIRLY QUICKLY
AS DRY AIR WILL FOLLOW. EXPECT BY 03Z SKIES SHOULD BECOME MOSTLY
CLEAR... AND TEMPS WILL RETURN TO MORE OF A SEASONAL AVERAGE FOR
THIS TIME OF THE YEAR IN THE LOW TO MID 60S.
FRIDAY WILL BE FAIRLY QUIET AS WEAK HIGH PRESSURE DEVELOPS IN THE
WAKE OF THE TROUGH. THIS WILL BE SHORT LIVED AS THE NEXT SYSTEM TO
IMPACT THE REGION IS EXPECTED TO MOVE THROUGH STARTING EARLY SAT
MORNING. IT LOOKS LIKE SCATTERED SHOWERS AND THUNDERSTORMS MAY BE
POSSIBLE THROUGH THE DAY ON SAT AS A WEAK FRONT/SFC TROUGH MOVES
THROUGH.
TEMPS ARE EXPECTED TO BE AT OR SLIGHTLY ABOVE THE SEASONAL AVERAGE
THROUGH THE FORECAST PERIOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
2 PM UPDATE...
FOLLOWED LATEST WPC GUIDANCE. TEMPERATURES NEAR NORMAL. UNSETTLED
BUT ONLY LOW CHC TO SCHC POPS. MODELS DO NOT AGREE ON TIMING OF
WEAK SYSTEMS MOVING THROUGH. AT UPPER LEVELS A BROAD TROUGH. THE
BEST CHANCE LOOKS LIKE MONDAY OR TUESDAY WITH A DECENT COLD FRONT
FOR EARLY AUGUST.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE EVENING HOURS (6Z) AS
MAINLY HIGH CLOUDS ADVECT OVER ALL TAF SITES. VIS SATELLITE
IMAGERY SHOWS A BAND OF MAINLY MID CLOUDS ACRS ERN LAKES WORKING
E WITH FRONTAL BOUNDARY THAT WILL REACH KSYR BY 10Z, KRME AT
11Z...KELM/KITH AT 12Z...KBGM AT 13Z AND KAVP BY 15Z. WE EXPECT
SHRA WITH ISLD TSRA TO ACCOMPANY THIS FRNT AND BAND OF CLOUDS BUT
ITS TIMING BEING IN THE MORNING LOOKS TO KEEP THE CHC/S FOR TSRA
DOWN SO DO NOT HAVE TSRA IN TAFS. LOOKING AT OBS UPSTREAM IT
LOOKS LIKE MAINLY VFR -SHRA SO HAVE TEMPO GROUP FOR VFR -SHRA 4000
FOOT CIG AS THIS BAND OF SHRA MOVES ACRS ALL TAF SITES. THE BAND
AFFECTS KSYR/KELM 12Z-15Z, KRME/KITH 13Z-16Z, KBGM 14Z-17Z AND
KAVP 15Z-18Z. MODELS INDICATE SOME SORT OF MARINE LAYER OR JUST AN
INCREASE IN LOW-LEVEL MOISTURE AFFECTS KAVP LATE TONIGHT. SOME OF
THE GUIDC HAS IFR CONDITIONS AT KAVP AND EVEN KBGM/KELM SO THERE
IS A LOT OF UNCERTAINTY HERE SO HAVE SOME MVFR CIG/VSBY 8-12Z TO
ACCOUNT FOR AT KAVP. MODELS ARE UNCERTAIN HOW FAR N AND W THIS
LOW-LEVEL MOISTURE MAKES IT OR IF IT EVEN SATURATES OUT INTO A LO
CLD SHIELD. SO LOTS OF UNCERTAINTY FOR ESP KAVP AND EVEN KBGM/KELM
BY 12Z.
WINDS WILL BE S TO SW OVERNIGHT UNDER 10 KNOTS AND W-NW 10-12
KNOTS WITH GUSTS 15-20 KNOTS HIGHER TERRAIN SITES BY THU PM.
.OUTLOOK...
THURSDAY NGT TO MONDAY...MAINLY VFR. POSSIBLY BRIEF MVFR IN
SHOWERS. ALSO RESTRICTIONS IN MORNING VALLEY FOG AT KELM POSSIBLE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KAH
NEAR TERM...KAH/RRM
SHORT TERM...KAH
LONG TERM...TAC
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
325 PM EDT TUE JUL 28 2015
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL BE THE RULE ACROSS THE NORTH COUNTRY
RIGHT THROUGH THE END OF THE WEEK. IN FACT...SOME LOCATIONS WILL
REACH THE 90 DEGREE MARK FOR THE FIRST TIME THIS SUMMER TODAY
THROUGH THURSDAY. WITH THE HEAT WILL COME HIGHER HUMIDITY AND THE
THREAT FOR SOME THUNDERSTORMS TODAY...BUT ESPECIALLY ON THURSDAY
WHEN A COLD FRONT MOVES INTO THE REGION. THE THUNDERSTORMS ON
THURSDAY WILL BE MORE NUMEROUS AND ALSO HAVE THE POTENTIAL TO BE
STRONG OR SEVERE.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1201 PM EDT TUESDAY...FORECAST PRETTY MUCH ON TRACK.
TEMPERATURES HAVE WARMED INTO THE 80S AREA-WIDE AS OF 12
NOON...WITH SEVERAL MORE HOURS OF WARMING TO GO. WILL SHOW HIGHS
IN THE MID 80S TO LOW 90S (WARMEST IN THE SAINT LAWRENCE VALLEY
AND LOWER CONNECTICUT RIVER VALLEY). BTV MAY FALL JUST SHORT OF
ITS FIRST 90F READING OF THE SEASON (CURRENT FORECAST OF 89F).
LATEST RAP ANALYSIS SHOWING 50 KNOTS OF 0-6KM SHEAR AND 1000 J/KG
OF SBCAPE/500 J/KG MLCAPE...BUT STILL WELL CAPPED. THE CU FIELD IS
NOW FINALLY STARTING TO GET GOING OVER THE HIGHER TERRAIN.
PREVIOUS THINKING WITH REGARDS TO CONVECTIVE POTENTIAL
REMAINS...ANY THREAT IS ISOLATED AT BEST...AND INITIATION
DEPENDENT ON TERRAIN.
PREVIOUS DISCUSSION FROM 1010 AM TUESDAY...
A RIDGE OF HIGH PRESSURE TO OUR SOUTH WILL NOSE INTO THE REGION
THROUGH TODAY. THIS ALONG WITH GRADUALLY BUILDING HEIGHTS ALOFT
WILL PROVIDE FOR MOSTLY SUNNY SKIES FOR MUCH OF THE DAY. AREAS OF
MORNING FOG HAVE BURNED OFF FOR THE MOST PART...WITH THE ONLY
OTHER CURRENT CLOUD COVER BEING SOME SCATTERED HIGH CLOUDS FROM
CONVECTIVE DEBRIS OVER CANADA. OTHERWISE...WILL SEE SOME CUMULUS
CLOUDS ACROSS THE REGION THIS AFTERNOON...ESPECIALLY HIGHER
TERRAIN. TEMPERATURES WILL RISE INTO THE MID/UPPER 80S WITH SOME
LOW 90S ALSO POSSIBLE IN THE LARGER VALLEYS. THIS COMBINED WITH
DEW POINTS IN THE 60S WILL LEAD TO SOME INSTABILITY (MLCAPE AROUND
1000 J/KG OR SO) BY THE AFTERNOON. CONVECTIVE POTENTIAL WILL BE
LIMITED HOWEVER BY POOR MID LEVEL LAPSE RATES...A WEAK CAP IN
PLACE...AND LACK OF A SURFACE BOUNDARY FOR A TRIGGER. THAT BEING
SAID...A WEAK FEATURE PASSING THROUGH ALOFT AND THE HIGHER TERRAIN
OF THE GREENS/ADIRONDACKS MAY PROVIDE JUST ENOUGH LIFT FOR
CONVECTIVE INITIATION AFTER 16Z. IF A FEW ISOLATED STORMS WERE TO
DEVELOP...THERE IS POTENTIAL FOR THEM TO BECOME STRONG TO
MARGINALLY SEVERE WITH 0-6KM AVERAGE BULK SHEAR AROUND 40 KNOTS.
STORM MOVEMENT EXPECTED TO BE GENERALLY SOUTHEAST.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AS OF 312 AM EDT TUESDAY...UPPER RIDGE BUILDS IN ON WEDNESDAY AND
THIS SHOULD HELP TO CAP THE CONVECTIVE POTENTIAL. BUT WITH PLENTY
OF INSTABILITY DEVELOPING ONCE AGAIN...SOMETHING IS GOING TO TRY
AND GET GOING OVER THE MOUNTAINS. HOWEVER...AREAL COVERAGE SHOULD
BE PRETTY LIMITED. ONCE AGAIN LOOKING AT HIGHS IN THE MID 80S TO
LOWER 90S. MAIN FOCUS IN THE SHORT TERM LOOKS TO BE THURSDAY AS
SHARP COLD FRONT MOVES EASTWARD INTO THE AREA DURING THE AFTERNOON
HOURS. FOR THE THIRD STRAIGHT DAY WE WILL SEE HIGHS IN THE MID 80S
TO LOWER 90S AND DEW POINTS IN THE 60S. THIS SHOULD RESULT IN CAPE
VALUES IN THE 1000 TO 1500 J/KG RANGE FOR SUFFICIENT INSTABILITY
THAT ALLOWS CONVECTION TO DEVELOP ONCE THE COLD FRONT MOVES IN.
DEEP LAYER SHEAR WILL BE INCREASING OVER THE TOP OF THE FRONT AND
INSTABILITY TO ENHANCE THE POTENTIAL FOR ORGANIZED STORMS WHICH
COULD BECOME STRONG TO SEVERE. WE WILL CONTINUE TO KEEP AN EYE ON
THIS SCENARIO. THE OTHER ELEMENT TO WATCH IS THE POTENTIAL FOR
THREE STRAIGHT DAYS OF 90 DEGREE WEATHER AND THAT WOULD BE
CONSIDERED A HEAT WAVE.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 325 PM EDT TUESDAY...SEASONABLE TEMPS AND WEATHER THROUGH
THE EXTENDED PERIOD AS LARGE-SCALE POLAR UPPER LOW TAKES UP
RESIDENCE OVER HUDSONS BAY LEAVING THE NORTHEAST IN PERSISTENT
BROAD TROUGH WITH THE AXIS MAINLY OVER THE GREAT LAKES.
WEAK PIECES OF SHORTWAVE ENERGY WILL BE MOVING THROUGH THE FLOW
ALOFT THROUGH THE PERIOD AND MAY BE ENHANCED BY DAYTIME HEATING TO
TRIGGER SHOWERS OR A THUNDERSTORM JUST ABOUT ANY DAY IN THE
EXTENDED FORECAST. LACK OF ANY STRONG FORCING FOR PRECIPITATION
AND LIMITED MOISTURE WILL KEEP ANY RAINFALL GENERALLY BE ON THE
LIGHT SIDE. MODEL DIFFERENCES WITH TIMING AND AMPLITUDE OF THE
VARIOUS SHORT WAVE FEATURES MAKE PINPOINTING ANY PARTICULAR DAY`S
WEATHER DIFFICULT.
A WEAK SURFACE BOUNDARY MAY BRING SCATTERED SHOWERS AND/OR STORMS
ON SATURDAY, BUT THE BEST CHANCES FOR PRECIP DURING THE PERIOD
LOOK TO BE MONDAY INTO TUESDAY AS THE UPPER LOW DIGS SLIGHTLY
SOUTHWARD FROM JAMES BAY TO THE GREAT LAKES. THIS WILL ALLOW A
WEAK COLD FRONT TO APPROACH THE AREA AS A BETTER FOCUS FOR
PRECIPITATION.
850 TEMPS RUNNING 10-14C WITH A TREND TOWARD COOLER BY TUE AS THE
TROF SAGS SOUTH. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR
NORMAL...MID 70S TO LOWER 80S WITH LOWS IN THE MID 50S TO LOWER
60S. SHOULD BE FAIRLY COMFORTABLE AS WELL WITH DEW POINTS
GENERALLY IN THE 50S TO LOW 60S.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...MAINLY VFR EXPECTED THROUGH THE PERIOD.
COULD SEE A FEW ISOLATED SHOWERS/STORMS THIS AFTERNOON MAINLY OVER
THE MOUNTAINS SO LEFT IT OUT FOR NOW. LIGHT NORTHWEST OR VARIABLE
WINDS THROUGH TOMORROW MORNING. CALM AGAIN AFTER 02Z LEADING TO
LIFR FOG AT KMPV/KSLK 08-12Z WEDNESDAY. CHANCE MVFR IN MIST
ELSEWHERE. MAINLY VFR AGAIN ON WEDNESDAY.
OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY...
WED: MAINLY VFR. EARLY MORNING IFR FOG POSSIBLE KSLK/KMPV.
THU: VFR WITH BRIEF MVFR/IFR IN SHOWERS/STORMS WITH PASSAGE OF
COLD FRONT. ISOLD SEVERE TURBULENCE/WINDS/HAIL POSSIBLE.
FRI: MAINLY VFR. SLGHT CHC PM -SHRA.
SAT: MAINLY VFR. CHANCE PM SHRA/TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...MUCCILLI
SHORT TERM...EVENSON
LONG TERM...SISSON
AVIATION...SISSON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
151 PM EDT TUE JUL 28 2015
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL BE THE RULE ACROSS THE NORTH COUNTRY
RIGHT THROUGH THE END OF THE WEEK. IN FACT...SOME LOCATIONS WILL
REACH THE 90 DEGREE MARK FOR THE FIRST TIME THIS SUMMER TODAY
THROUGH THURSDAY. WITH THE HEAT WILL COME HIGHER HUMIDITY AND THE
THREAT FOR SOME THUNDERSTORMS TODAY...BUT ESPECIALLY ON THURSDAY
WHEN A COLD FRONT MOVES INTO THE REGION. THE THUNDERSTORMS ON
THURSDAY WILL BE MORE NUMEROUS AND ALSO HAVE THE POTENTIAL TO BE
STRONG OR SEVERE.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1201 PM EDT TUESDAY...FORECAST PRETTY MUCH ON TRACK.
TEMPERATURES HAVE WARMED INTO THE 80S AREA-WIDE AS OF 12
NOON...WITH SEVERAL MORE HOURS OF WARMING TO GO. WILL SHOW HIGHS
IN THE MID 80S TO LOW 90S (WARMEST IN THE SAINT LAWRENCE VALLEY
AND LOWER CONNECTICUT RIVER VALLEY). BTV MAY FALL JUST SHORT OF
ITS FIRST 90F READING OF THE SEASON (CURRENT FORECAST OF 89F).
LATEST RAP ANALYSIS SHOWING 50 KNOTS OF 0-6KM SHEAR AND 1000 J/KG
OF SBCAPE/500 J/KG MLCAPE...BUT STILL WELL CAPPED. THE CU FIELD IS
NOW FINALLY STARTING TO GET GOING OVER THE HIGHER TERRAIN.
PREVIOUS THINKING WITH REGARDS TO CONVECTIVE POTENTIAL
REMAINS...ANY THREAT IS ISOLATED AT BEST...AND INITIATION
DEPENDENT ON TERRAIN.
PREVIOUS DISCUSSION FROM 1010 AM TUESDAY...
A RIDGE OF HIGH PRESSURE TO OUR SOUTH WILL NOSE INTO THE REGION
THROUGH TODAY. THIS ALONG WITH GRADUALLY BUILDING HEIGHTS ALOFT
WILL PROVIDE FOR MOSTLY SUNNY SKIES FOR MUCH OF THE DAY. AREAS OF
MORNING FOG HAVE BURNED OFF FOR THE MOST PART...WITH THE ONLY
OTHER CURRENT CLOUD COVER BEING SOME SCATTERED HIGH CLOUDS FROM
CONVECTIVE DEBRIS OVER CANADA. OTHERWISE...WILL SEE SOME CUMULUS
CLOUDS ACROSS THE REGION THIS AFTERNOON...ESPECIALLY HIGHER
TERRAIN. TEMPERATURES WILL RISE INTO THE MID/UPPER 80S WITH SOME
LOW 90S ALSO POSSIBLE IN THE LARGER VALLEYS. THIS COMBINED WITH
DEW POINTS IN THE 60S WILL LEAD TO SOME INSTABILITY (MLCAPE AROUND
1000 J/KG OR SO) BY THE AFTERNOON. CONVECTIVE POTENTIAL WILL BE
LIMITED HOWEVER BY POOR MID LEVEL LAPSE RATES...A WEAK CAP IN
PLACE...AND LACK OF A SURFACE BOUNDARY FOR A TRIGGER. THAT BEING
SAID...A WEAK FEATURE PASSING THROUGH ALOFT AND THE HIGHER TERRAIN
OF THE GREENS/ADIRONDACKS MAY PROVIDE JUST ENOUGH LIFT FOR
CONVECTIVE INITIATION AFTER 16Z. IF A FEW ISOLATED STORMS WERE TO
DEVELOP...THERE IS POTENTIAL FOR THEM TO BECOME STRONG TO
MARGINALLY SEVERE WITH 0-6KM AVERAGE BULK SHEAR AROUND 40 KNOTS.
STORM MOVEMENT EXPECTED TO BE GENERALLY SOUTHEAST.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY/...
AS OF 312 AM EDT TUESDAY...UPPER RIDGE BUILDS IN ON WEDNESDAY AND
THIS SHOULD HELP TO CAP THE CONVECTIVE POTENTIAL. BUT WITH PLENTY
OF INSTABILITY DEVELOPING ONCE AGAIN...SOMETHING IS GOING TO TRY
AND GET GOING OVER THE MOUNTAINS. HOWEVER...AREAL COVERAGE SHOULD
BE PRETTY LIMITED. ONCE AGAIN LOOKING AT HIGHS IN THE MID 80S TO
LOWER 90S. MAIN FOCUS IN THE SHORT TERM LOOKS TO BE THURSDAY AS
SHARP COLD FRONT MOVES EASTWARD INTO THE AREA DURING THE AFTERNOON
HOURS. FOR THE THIRD STRAIGHT DAY WE WILL SEE HIGHS IN THE MID 80S
TO LOWER 90S AND DEW POINTS IN THE 60S. THIS SHOULD RESULT IN CAPE
VALUES IN THE 1000 TO 1500 J/KG RANGE FOR SUFFICIENT INSTABILITY
THAT ALLOWS CONVECTION TO DEVELOP ONCE THE COLD FRONT MOVES IN.
DEEP LAYER SHEAR WILL BE INCREASING OVER THE TOP OF THE FRONT AND
INSTABILITY TO ENHANCE THE POTENTIAL FOR ORGANIZED STORMS WHICH
COULD BECOME STRONG TO SEVERE. WE WILL CONTINUE TO KEEP AN EYE ON
THIS SCENARIO. THE OTHER ELEMENT TO WATCH IS THE POTENTIAL FOR
THREE STRAIGHT DAYS OF 90 DEGREE WEATHER AND THAT WOULD BE
CONSIDERED A HEAT WAVE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 340 AM EDT TUESDAY...OVERALL CONDITIONS REMAIN SOMEWHAT
UNSETTLED FOR THE EXTENDED PERIOD AS THE AFOREMENTIONED COLD FRONT
SHIFTS EAST OF THE REGION THURSDAY NIGHT, BUT A LARGE-SCALE POLAR
TROUGH SETS UP BEHIND IT TAKING RESIDENCE ACROSS THE GREAT LAKES
AND NORTHEAST STATES FOR DAYS 4 THROUGH 7. WITH THE CENTER OF THE
UPPER LOW WELL TO OUR NORTH, PIECES OF SHORTWAVE ENERGY MOVING
THROUGH THE FLOW ALOFT ARE RATHER WEAK ACROSS THE FORECAST AREA,
SO WITH THE LACK OF ANY STRONG FORCING CHANCES FOR PRECIPITATION
IS RATHER LOW. A WEAK SURFACE BOUNDARY MAY BRING A FEW ISOLATED TO
SCATTERED SHOWERS AND/OR STORMS ON SATURDAY, BUT THE BEST CHANCES
FOR PRECIP DURING THE PERIOD LOOK TO BE SUNDAY NIGHT INTO TUESDAY
AS THE UPPER LOW DIGS SOUTHWARD FROM JAMES BAY TO THE GREAT LAKES
ALLOWING FOR A DEEPER SOUTHWESTERLY FLOW TO DEVELOP ACROSS THE
NORTH COUNTRY. TEMPERATURES THROUGH THE PERIOD WILL BE COOLER THAN
THIS WEEK, BUT VERY SEASONAL WITH HIGHS IN THE UPPER 70S TO LOW
80S, AND LOWS IN THE MID 50S TO LOW 60S. SHOULD BE FAIRLY
COMFORTABLE AS WELL WITH DEW POINTS GENERALLY IN THE 50S TO LOW
60S.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...MAINLY VFR EXPECTED THROUGH THE PERIOD.
COULD SEE A FEW ISOLATED SHOWERS/STORMS THIS AFTERNOON MAINLY OVER
THE MOUNTAINS SO LEFT IT OUT FOR NOW. LIGHT NORTHWEST OR VARIABLE
WINDS THROUGH TOMORROW MORNING. CALM AGAIN AFTER 02Z LEADING TO
LIFR FOG AT KMPV/KSLK 08-12Z WEDNESDAY. CHANCE MVFR IN MIST
ELSEWHERE. MAINLY VFR AGAIN ON WEDNESDAY.
OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY...
WED: MAINLY VFR. EARLY MORNING IFR FOG POSSIBLE KSLK/KMPV.
THU: VFR WITH BRIEF MVFR/IFR IN SHOWERS/STORMS WITH PASSAGE OF
COLD FRONT. ISOLD SEVERE TURBULENCE/WINDS/HAIL POSSIBLE.
FRI: MAINLY VFR. SLGHT CHC PM -SHRA.
SAT: MAINLY VFR. CHANCE PM SHRA/TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...MUCCILLI
SHORT TERM...EVENSON
LONG TERM...LAHIFF
AVIATION...SISSON
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1207 PM EDT TUE JUL 28 2015
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL BE THE RULE ACROSS THE NORTH COUNTRY
RIGHT THROUGH THE END OF THE WEEK. IN FACT...SOME LOCATIONS WILL
REACH THE 90 DEGREE MARK FOR THE FIRST TIME THIS SUMMER TODAY
THROUGH THURSDAY. WITH THE HEAT WILL COME HIGHER HUMIDITY AND THE
THREAT FOR SOME THUNDERSTORMS TODAY...BUT ESPECIALLY ON THURSDAY
WHEN A COLD FRONT MOVES INTO THE REGION. THE THUNDERSTORMS ON
THURSDAY WILL BE MORE NUMEROUS AND ALSO HAVE THE POTENTIAL TO BE
STRONG OR SEVERE.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1201 PM EDT TUESDAY...FORECAST PRETTY MUCH ON TRACK.
TEMPERATURES HAVE WARMED INTO THE 80S AREA-WIDE AS OF 12
NOON...WITH SEVERAL MORE HOURS OF WARMING TO GO. WILL SHOW HIGHS
IN THE MID 80S TO LOW 90S (WARMEST IN THE SAINT LAWRENCE VALLEY
AND LOWER CONNECTICUT RIVER VALLEY). BTV MAY FALL JUST SHORT OF
ITS FIRST 90F READING OF THE SEASON (CURRENT FORECAST OF 89F).
LATEST RAP ANALYSIS SHOWING 50 KNOTS OF 0-6KM SHEAR AND 1000 J/KG
OF SBCAPE/500 J/KG MLCAPE...BUT STILL WELL CAPPED. THE CU FIELD IS
NOW FINALLY STARTING TO GET GOING OVER THE HIGHER TERRAIN.
PREVIOUS THINKING WITH REGARDS TO CONVECTIVE POTENTIAL
REMAINS...ANY THREAT IS ISOLATED AT BEST...AND INITIATION
DEPENDENT ON TERRAIN.
PREVIOUS DISCUSSION FROM 1010 AM TUESDAY...
A RIDGE OF HIGH PRESSURE TO OUR SOUTH WILL NOSE INTO THE REGION
THROUGH TODAY. THIS ALONG WITH GRADUALLY BUILDING HEIGHTS ALOFT
WILL PROVIDE FOR MOSTLY SUNNY SKIES FOR MUCH OF THE DAY. AREAS OF
MORNING FOG HAVE BURNED OFF FOR THE MOST PART...WITH THE ONLY
OTHER CURRENT CLOUD COVER BEING SOME SCATTERED HIGH CLOUDS FROM
CONVECTIVE DEBRIS OVER CANADA. OTHERWISE...WILL SEE SOME CUMULUS
CLOUDS ACROSS THE REGION THIS AFTERNOON...ESPECIALLY HIGHER
TERRAIN. TEMPERATURES WILL RISE INTO THE MID/UPPER 80S WITH SOME
LOW 90S ALSO POSSIBLE IN THE LARGER VALLEYS. THIS COMBINED WITH
DEW POINTS IN THE 60S WILL LEAD TO SOME INSTABILITY (MLCAPE AROUND
1000 J/KG OR SO) BY THE AFTERNOON. CONVECTIVE POTENTIAL WILL BE
LIMITED HOWEVER BY POOR MID LEVEL LAPSE RATES...A WEAK CAP IN
PLACE...AND LACK OF A SURFACE BOUNDARY FOR A TRIGGER. THAT BEING
SAID...A WEAK FEATURE PASSING THROUGH ALOFT AND THE HIGHER TERRAIN
OF THE GREENS/ADIRONDACKS MAY PROVIDE JUST ENOUGH LIFT FOR
CONVECTIVE INITIATION AFTER 16Z. IF A FEW ISOLATED STORMS WERE TO
DEVELOP...THERE IS POTENTIAL FOR THEM TO BECOME STRONG TO
MARGINALLY SEVERE WITH 0-6KM AVERAGE BULK SHEAR AROUND 40 KNOTS.
STORM MOVEMENT EXPECTED TO BE GENERALLY SOUTHEAST.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH THURSDAY/...
AS OF 312 AM EDT TUESDAY...UPPER RIDGE BUILDS IN ON WEDNESDAY AND
THIS SHOULD HELP TO CAP THE CONVECTIVE POTENTIAL. BUT WITH PLENTY
OF INSTABILITY DEVELOPING ONCE AGAIN...SOMETHING IS GOING TO TRY
AND GET GOING OVER THE MOUNTAINS. HOWEVER...AREAL COVERAGE SHOULD
BE PRETTY LIMITED. ONCE AGAIN LOOKING AT HIGHS IN THE MID 80S TO
LOWER 90S. MAIN FOCUS IN THE SHORT TERM LOOKS TO BE THURSDAY AS
SHARP COLD FRONT MOVES EASTWARD INTO THE AREA DURING THE AFTERNOON
HOURS. FOR THE THIRD STRAIGHT DAY WE WILL SEE HIGHS IN THE MID 80S
TO LOWER 90S AND DEW POINTS IN THE 60S. THIS SHOULD RESULT IN CAPE
VALUES IN THE 1000 TO 1500 J/KG RANGE FOR SUFFICIENT INSTABILITY
THAT ALLOWS CONVECTION TO DEVELOP ONCE THE COLD FRONT MOVES IN.
DEEP LAYER SHEAR WILL BE INCREASING OVER THE TOP OF THE FRONT AND
INSTABILITY TO ENHANCE THE POTENTIAL FOR ORGANIZED STORMS WHICH
COULD BECOME STRONG TO SEVERE. WE WILL CONTINUE TO KEEP AN EYE ON
THIS SCENARIO. THE OTHER ELEMENT TO WATCH IS THE POTENTIAL FOR
THREE STRAIGHT DAYS OF 90 DEGREE WEATHER AND THAT WOULD BE
CONSIDERED A HEAT WAVE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 340 AM EDT TUESDAY...OVERALL CONDITIONS REMAIN SOMEWHAT
UNSETTLED FOR THE EXTENDED PERIOD AS THE AFOREMENTIONED COLD FRONT
SHIFTS EAST OF THE REGION THURSDAY NIGHT, BUT A LARGE-SCALE POLAR
TROUGH SETS UP BEHIND IT TAKING RESIDENCE ACROSS THE GREAT LAKES
AND NORTHEAST STATES FOR DAYS 4 THROUGH 7. WITH THE CENTER OF THE
UPPER LOW WELL TO OUR NORTH, PIECES OF SHORTWAVE ENERGY MOVING
THROUGH THE FLOW ALOFT ARE RATHER WEAK ACROSS THE FORECAST AREA,
SO WITH THE LACK OF ANY STRONG FORCING CHANCES FOR PRECIPITATION
IS RATHER LOW. A WEAK SURFACE BOUNDARY MAY BRING A FEW ISOLATED TO
SCATTERED SHOWERS AND/OR STORMS ON SATURDAY, BUT THE BEST CHANCES
FOR PRECIP DURING THE PERIOD LOOK TO BE SUNDAY NIGHT INTO TUESDAY
AS THE UPPER LOW DIGS SOUTHWARD FROM JAMES BAY TO THE GREAT LAKES
ALLOWING FOR A DEEPER SOUTHWESTERLY FLOW TO DEVELOP ACROSS THE
NORTH COUNTRY. TEMPERATURES THROUGH THE PERIOD WILL BE COOLER THAN
THIS WEEK, BUT VERY SEASONAL WITH HIGHS IN THE UPPER 70S TO LOW
80S, AND LOWS IN THE MID 50S TO LOW 60S. SHOULD BE FAIRLY
COMFORTABLE AS WELL WITH DEW POINTS GENERALLY IN THE 50S TO LOW
60S.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
THROUGH 12Z WEDNESDAY...GENERALLY VFR CONDITIONS ARE EXPECTED
THROUGH THE PERIOD. IFR FOG AT KMPV WILL BURN OFF OVER THE NEXT 2
HOURS WITH CLEAR SKIES ELSEWHERE TRENDING TO SCATTERED CUMULUS BY
MID-DAY. COULD SEE A FEW ISOLATED SHOWERS/STORMS THIS AFTERNOON,
BUT TOO MUCH UNCERTAINTY EXISTS IN REGARDS TO AREAL COVERAGE SO
WILL LEAVE OUT FOR NOW. LIGHT NORTHWEST AT 5-10 KNOTS TODAY GO
CALM AGAIN AFTER 02Z LEADING TO IFR FOG AT KMPV/KSLK AFTER 07Z
WEDNESDAY.
OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY...
12Z WED - 12Z THU: MAINLY VFR. EARLY MORNING IFR FOG POSSIBLE.
12Z THU - 00Z FRI: VFR WITH BRIEF MVFR/IFR IN SHOWERS/STORMS WITH
PASSAGE OF COLD FRONT. STRONG TO SEVERE STORMS POSSIBLE WITH
SEVERE TURBULENCE/WINDS/HAIL POSSIBLE IN HEAVIER CORES.
00Z FRI - 00Z SUN: MAINLY VFR. EARLY MORNING IFR FOG POSSIBLE.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...MUCCILLI
SHORT TERM...EVENSON
LONG TERM...LAHIFF
AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
153 AM EDT TUE JUL 28 2015
.SYNOPSIS...A SERIES OF PERTURBATIONS ALOFT INTERACTING WITH A MOIST
AND UNSTABLE AIR MASS WILL TRIGGER SCATTERED THUNDERSTORMS...MAINLY
DURING THE AFTERNOON AND EVENING HOURS...THROUGH THE REMAINDER OF
THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 925 PM MONDAY...
DIURNALLY INDUCED CONVECTION IS BEGINNING TO DISSIPATE WITH THE
EXCEPTION OF AN AREA OF PERSISTENT RAINFALL IN THE SOUTHWEST
PIEDMONT COINCIDENT WITH TWO CONVERGING SURFACE BOUNDARIES...AIDED
BY SOME DIVERGENCE ALOFT...AS SEEN CLEARLY IN THE WATER VAPOR
IMAGERY. WHILE THIS ACTIVITY COULD PERSIST FOR A LITTLE
WHILE...GENERALLY EXPECT IT TO WEAKEN OVER THE NEXT COUPLE OF HOURS.
WHILE CENTRAL NC REMAINS ON THE BACK/FRONT SIDE OF AN UPPER LEVEL
TROUGH/RIDGE...WATER VAPOR SHOWS ANOTHER SURGE OF DRY AIR ALOFT
MAKING A SOUTHWARD PROGRESSION THROUGH VA AT THIS TIME. TO THE WEST
OF THIS HOWEVER...A STEADY STREAM OF MOISTURE SHOULD CONTINUE TO
FEED INTO THE WESTERN COUNTIES OF THE CWA. HIGH RESOLUTION MODELS
WEAKEN CONVECTION THROUGH THE OVERNIGHT HOURS BUT THE HRRR HOLDS
ONTO SOME RAINFALL IN THE SW PIEDMONT FOR LONGER THAN THE WRF
SIMULATIONS WHICH IS NOT OUT OF THE QUESTION AT THIS POINT. WILL
START TO SEE POCKETS OF FOG AND LOW STRATUS IN RAIN MOISTENED AREAS
AS WELL AS POSSIBLY IN THE EASTERN COUNTIES CLOSER TO SUNRISE. LOW
TEMPERATURES TONIGHT IN THE LOW TO MIDDLE 70S...COOLEST IN THE NE
COUNTIES WHERE UPPER LEVEL CLOUDINESS MAY CEASE ONCE/IF DRY AIR
ALOFT ARRIVES.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 325 PM MONDAY...
A WEAK SFC TROUGH WILL REMAIN STALLED IN VICINITY OF THE WESTERN
PIEDMONT. ALOFT...AN UPPER RIDGE CENTERED OVER THE SOUTHERN PLAINS
BRIEFLY AMPLIFIES INTO THE WESTERN LAKES...VEERING FLOW ALOFT OVER
CENTRAL NC TO A NWLY DIRECTION. WEAK PERTURBATIONS EMBEDDED IN THIS
FLOW ALOFT INTERACTING WITH THE STALLED SFC TROUGH AND AVAILABLE
MOISTURE/INSTABILITY SHOULD TRIGGER SCATTERED CONVECTION...MAINLY IN
THE AFTERNOON AND EVENING HOURS. PROBABILITY OF SCATTERED CONVECTION
APPEARS BEST IN VICINITY OF THE STALLED SFC TROUGH IN THE WESTERN
PIEDMONT...AND IN VICINITY WHERE THE PERTURBATIONS ALOFT TRACK
THROUGH THE REGION. THUS...POPS WILL VARY FROM SOLID
CHANCE(SCATTERED) ACROSS THE NORTHERN PIEDMONT-NORTHERN COASTAL
PLAIN TO SLIGHT CHANCE(ISOLATED)OVER THE FAR SOUTHERN COUNTIES.
BULK OF CONVECTION WILL DIMINISH WITH LOSS OF HEATING TUESDAY
EVENING THOUGH A FEW SHOWERS MAY OCCUR WELL INTO THE NIGHT DUE TO
PERTURBATIONS IN THE NW FLOW ALOFT INTERACTING WITH THE MOISTURE
RICH AIR MASS OVER OUR REGION.
WHILE A STRONG OR SEVERE STORM CANNOT BE RULED OUT TUESDAY
AFTERNOON...BULK OF CONVECTIVE PARAMETERS POINT TOWARD MOST OF THE
STORMS REMAINING BELOW SEVERE CRITERIA.
MAX TEMPS TUESDAY HIGHLY DEPENDENT ON EXTENT OF EARLY MORNING CLOUDS
AND TIMING OF AFTERNOON CONVECTION. FAVORING PARTIAL SUN TO OCCUR
FOR MOST OF THE LATE MORNING-EARLY AFTERNOON...BOOSTING TEMPS WELL
INTO THE 80S-AROUND 90. IF LOW CLOUDS LINGER PAST NOON OR CONVECTION
DEVELOP BY NOON-2 PM...THAN MAX TEMPS MAY END UP BEING 3-5 DEGREES
COOLER THAN FORECAST. MIN TEMPS TUESDAY NIGHT 70-74.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 245 PM MONDAY...
MEDIUM RANGE MODELS ARE IN GENERAL AGREEMENT IN SHOWING A MID LEVEL
RIDGE CENTERED ACROSS THE CENTRAL/SOUTHERN PLAINS AND LOWER MS RIVER
VALLEY TO START THE PERIOD (WEDNESDAY)... THEN RETROGRADING IT
WESTWARD ACROSS THE WESTERN U.S. BY LATE WEEK. THE MID LEVEL RIDGE
IS FORECAST TO BUILD NORTH/NORTHWESTWARD AS IT RETROGRADES...
HELPING TO AMPLIFY THE MID/UPPER LEVEL FLOW PATTERN ACROSS THE
CONUS. THIS SHOULD YIELD BROAD MID LEVEL TROUGHING FOR CENTRAL NC
LATE WEEK INTO EARLY NEXT WEEK... WITH A SURFACE COLD FRONT PUSHING
INTO THE AREA FROM THE NORTH AND WEST LATE THURSDAY INTO FRIDAY.
HOWEVER... THE STRONGER FLOW ALOFT WILL REMAIN TO THE NORTH OF
CENTRAL NC... YIELDING GENERALLY WEAK DEEP LAYER SHEAR. QUESTIONS
STILL REMAIN IF THE FRONT WILL PUSH THROUGH THE AREA OR SETTLE
ACROSS SOUTHEASTERN PORTIONS OF CENTRAL NC... AND RESULTANT HOW LONG
PRECIP CHANCES WILL CONTINUE ACROSS CENTRAL NC. FOR NOW WILL TO
TREND THE FORECAST TOWARDS AN UNSETTLED PATTERN FOR LATE THURSDAY
THROUGH SUNDAY... WITH THE POTENTIAL FOR HIGH MOISTURE CONTENT AIR
TO ADVECT INTO THE FROM THE NORTHEASTERN GULF OF MEXICO ALONG WITH
POTENTIALLY A FEW WEAK DISTURBANCES LIFTING NORTH-NORTHEASTWARD AND
ACROSS SOUTH/EASTERN PORTIONS OF THE FA. HOWEVER... DEPENDING ON HOW
FAR SOUTH AND EAST THE BOUNDARY MAKES IT WILL DETERMINE HOW MUCH OF
THE AREA SEE A GOOD CHANCE FOR SHOWERS AND STORMS OVER THE
WEEKEND... ALONG WITH THE POTENTIAL FOR HEAVY RAIN. THUS... WILL
LIMIT POPS TO CHANCE FOR NOW BUT RAISE THEM A BIT... WITH THE
HIGHEST POPS SOUTH/SOUTHEAST THIS WEEKEND.
HIGH TEMPS AHEAD OF THE FRONT ON WEDNESDAY AND THURSDAY ARE EXPECTED
TO BE NEAR NORMAL... GENERALLY AROUND 90 TO THE LOWER TO MID 90S.
HIGH BEHIND THE FRONT WILL GENERALLY BE IN THE MID TO UPPER 80S...
WITH A FEW LOCATIONS TOUCHING THE LOWER 90S... DEPENDING ON THE
PRECIP. LOWS AHEAD OF THE FRONT AREA EXPECTED TO BE IN THE LOWER TO
MID 70S.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 150 AM TUESDAY...
CONVECTION HAS DIMINISHED OVER CENTRAL NC AND THE ONLY REMAINING
STORMS ARE NORTH OF THE NC-VA BORDER. THE REST OF THE NIGHT SHOULD
BE QUIET WITH REGARDS TO CONVECTION...WITH STRATUS POSSIBLE IN A
FAIRLY WELL ESTABLISHED SOUTHEASTERLY RETURN FLOW. GIVEN THIS
RETURN FLOW AND LOW-LEVEL MOISTENING...ALONG WITH EARLIER CLUSTERS
OF STORMS OVER THE WESTERN PIEDMONT...STRATUS MAY END UP BEING MORE
WIDESPREAD WEST OF KRDU AND IMPACT KGSO/KINT. HOWEVER...THESE
SIGNALS ARE MIXED IN MODEL GUIDANCE...AND CONFIDENCE IS STILL LOW
GIVEN THE LACK OF DEVELOPMENT SO FAR. PATCHES OF HIGH CLOUDS WILL
ALSO CONTINUE TO STREAMING FROM THE NORTHWEST...WITH SOME MVFR/IFR
VSBYS POSSIBLE IN AREAS WHERE SKIES ARE CLEAR FOR AN EXTENDED AMOUNT
OF TIME.
WHAT STRATUS THAT FORMS WILL BURN OFF QUICKLY THIS MORNING AND
SCATTERED STORMS WILL BE POSSIBLE AGAIN THIS AFTERNOON...WITH
SLIGHTLY HIGHER CONFIDENCE IN STORMS IN THE VICINITY OF
KGSO/KINT/KRDU.
OUTLOOK: EARLY MORNING STRATUS AND/OR FOG WILL BE POSSIBLE WEDNESDAY
AND THURSDAY WITH AFTERNOON STORMS...MAINLY WEST...EACH DAY. A COLD
FRONT WILL THEN MOVE INTO THE AREA ON FRIDAY...POTENTIALLY STALLING
OVER EASTERN NC THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...22
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
108 AM EDT TUE JUL 28 2015
.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY WEAKEN THROUGH MID WEEK. A PIEDMONT
TROUGH WILL FORM AS WEAK LOW PRESSURE REMAINS OFF THE SOUTHEAST
COAST. A COLD FRONT WILL MOVE INTO THE AREA AND STALL DURING THE
WEEKEND BEFORE FINALLY DISSIPATING ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1 AM TUESDAY...AN AREA OF SLOW MOVING SHOWERS AND A FEW
RUMBLES OF THUNDER...IN ASSOCIATION WITH A MID-LEVEL SHORTWAVE
DROPPING S ACROSS THE CAROLINAS...WAS LOCATED NEAR THE NW CORNER
OF THE FORECAST AREA. WILL MAINTAIN A SMALL RISK FOR A SHOWER OR
THUNDERSTORM INTO THE OVERNIGHT...ROUGHLY ALONG AND NW OF A LBT TO
UDG LINE. THE HIGH RESOLUTION HRRR SHOWS THIS CLUSTER BASICALLY
WASHING OUT THROUGH 2-3 AM AS IT SUCCUMBS TO A STABILIZING
ENVIRONMENT. THE GROWING GROUND CLUTTER PATTERN AT KLTX SHOWS THIS
STABILIZATION ALREADY WELL UNDERWAY.
SHALLOW SHOWERS SHOULD AGAIN DEVELOP OFFSHORE OVERNIGHT AND SOME
OF THESE SHOWERS WILL MAKE A RUN FOR THE COAST IN THE LOW-LEVEL
EASTERLY FLOW. HOWEVER...IT LOOKS LIKE MOST OF THIS ACTIVITY IS
DESTINED TO REMAIN OFFSHORE.
THE LOWEST LEVELS HAVE MOISTENED CONSIDERABLY IN THE PAST 24 HOURS.
DEWPOINTS WERE IN THE LOW AND MID 70S THIS EVE. GIVEN THE EXTENT
AND THICKNESS OF THE CONVECTIVE CLOUD DEBRIS TOPPING THE RIDGE AND
MOVING ACROSS THE CAROLINAS...WILL RAISE THE MINIMUMS ABOUT A
CATEGORY...MAINLY MID AND UPPER 70S. ALSO...GIVEN THE LARGER
DEWPOINT DEPRESSIONS...DO NOT EXPECT THE FOG TO RESTRICT VISIBILITY
SIGNIFICANTLY AND I HAVE REMOVED MENTION FOR THE EARLY MORNING
HOURS. THERE COULD VERY WELL BE SOME LOW STRATUS TOWARD MORNING
HOWEVER.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...INTERESTING OVER THE MID-TERM AS TROUGHINESS
AND WEAK LOWER PRESSURE REMAINS OFF THE COAST. ALSO...A PIEDMONT
TROUGH DEVELOPS INLAND WITH AN EAST TO NORTHEAST FLOW. ALOFT
PRECIPITABLE WATERS EDGE UP TO NEAR 2 INCHES. NO LARGE SYNOPTIC
FORCING ALOFT SO 20 TO 30 PERCENT CHANCE OF DIURNAL CONVECTION IS
ANTICIPATED THROUGH THIS PERIOD.
WITH A NORTHEAST TO EAST FLOW DAILY HIGHS WILL BE IN THE UPPER
80S AT THE BEACHES AND MIDDLE 90S IN THE FAR WESTERN PORTIONS OF
THE FORECAST AREA. MIDDLE 70S WILL BE THE LOWS EACH DAY. THE
COMBINATION OF HIGH TEMPERATURES AND MOISTURE WILL BRING HEAT
INDICES TO 100 TO 104 INLAND BOTH DAYS.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...THURSDAY WILL LIKELY BE THE LAST DAY WITH A
FAIRLY `NORMAL` DISTRIBUTION OF SHOWERS AND THUNDERSTORMS AS THEY
WILL MOSTLY BE TRIGGERED BY MESOSCALE PROCESSES. THE EXCEPTION MAY
BE FAR INLAND ZONES AS A COLD FRONT WILL BE APPROACHING BUT THE
STEERING FLOW COULD PUSH THEM INTO THOSE AREAS LATE IN THE DAY.
ALL BETS ARE OFF FRIDAY AND OVER THE WEEKEND HOWEVER AS THIS
BOUNDARY DROPS INTO THE REGION AND STALLS. NOT ONLY WILL THIS
BOUNDARY BE IN THE VICINITY TO KEEP THINGS UNSETTLED BUT THERE BE
A WEAKNESS IN THE HEIGHT FIELD OVER THE REGION IN BETWEEN TWO
UPPER RIDGES, ONE OFF THE ATLANTIC COAST AND THE OTHER OVER MUCH
OF THE SOUTHWESTERN U.S. HIGH END CHANCE TO LIKELY POPS APPEAR
WARRANTED FOR MUCH OF THE PERIOD THOUGH AT THIS POINT IT`S TOUGH
TO SAY WHICH DAY WILL BE THE WETTEST. THIS IS MADE EVEN MORE TRUE
BY THE FACT THAT THERE COULD BE TROPICAL DEVELOPMENT DRAWN UP THE
COAST. THE ADDED CLOUD COVER WILL SUBTRACT FROM THE PRE-FRONTAL
WARMTH BY A FEW DEGREES BUT AT THE SAME TIME KEEP NIGHTTIME LOWS
CLOSE TO OR A LITTLE ABOVE CLIMO.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...WEAK HIGH PRESSURE IS STILL IN CONTROL OF THE REGION.
ISOLATED CONVECTION IS POSSIBLE OVER THE NORTHWEST PORTION OF THE
AREA...ASSOCIATED WITH THE LEADING EDGE OF A SHORT WAVE. THIS MAY
HINDER FOG FORMATION EARLY...BUT EXPECT FOG TO FORM AFTER 08Z
MAINLY IN THE MVFR RANGE...WITH A BRIEF ONE TO TWO HOUR PERIOD OF
NEAR IFR CONDITIONS POSSIBLE NEAR SUNRISE. EASTERLY WINDS ARE
EXPECTED ON TUESDAY. A WEAK SHORT WAVE MAY KICK OFF SCATTERED
ACTIVITY IN THE AFTERNOON...MAINLY OVER THE NORTHERN PORTION OF
THE CWA. HAVE ADDED VCTS TO THE NORTHERN TERMINALS.
EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD...WITH
ISOLATED AFTERNOON CONVECTION POSSIBLE TUESDAY THROUGH THURSDAY
WITH SCATTERED ACTIVITY FRIDAY AND SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1 AM TUESDAY...WEAK HIGH PRESSURE WILL CONTINUE TO BE THE
MAIN INFLUENCE ACROSS THE WATERS WITH AN INVERTED TROUGH POKING
NORTHWARD ALONG THE OFFSHORE CAROLINA WATERS. THE PRESSURE
GRADIENT WILL REMAIN LAX AND THIS WILL KEEP WIND SPEEDS AROUND 10
KT THROUGH THE NIGHT. THE DIRECTION WILL BE EASTERLY. SEAS WILL BE
2 TO 3 FT WITH 4 FT SEAS OUT AROUND BUOY 41013. A WEAK ESE SWELL
ON THE ORDER OF 10 TO 11 SECONDS WILL PERSIST.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...SYNOPTIC A WEAK TROUGH OF LOW PRESSURE WILL
REMAIN TO THE SOUTH AND EAST OF THE WATERS WITH THE MODELS TRYING
TO DEVELOP WEAK LOW PRESSURE ALONG THIS BOUNDARY. WINDS WILL BE
MAINLY FROM THE EAST WITH WIND SPEED AROUND 10 KNOTS. SEAS WILL
RUN FROM 1 TO 3 FEET DURING THIS TIME AS WELL.
LONG TERM /THURSDAY THROUGH SATURDAY...
AS OF 300 PM MONDAY...WINDS FINALLY ACQUIRE A MORE TYPICAL
SOUTHERLY COMPONENT ON THURSDAY AS FLOW VEERS AHEAD OF AN
APPROACHING COLD FRONT. A SOUTHEASTERLY WIND MAY BE MORE LIKELY
THAN A BERMUDA HIGH INDUCED SOUTHWESTERLY FLOW THOUGH SOME WEAK
TROUGHINESS OFF THE COAST MAKES IT TOUGH TO SAY. THIS WEAK FEATURE
OFFSHORE SHOULD HELP TO KEEP WINDS LIGHT THOUGH WITH SPEEDS LIKELY
CAPPED AT 10KT. THE APPROACH OF THE FRONT ON FRIDAY WILL BRING A
SOUTHWESTERLY WIND AND LIKELY ADD A FEW KNOTS FOR A GENERAL
10-15KT FORECAST AREA-WIDE. SATURDAY`S FORECAST WILL HINGE UPON
WHERE THIS BOUNDARY STALLS WITH IS A LITTLE UNCERTAIN AT THIS
POINT. SOUTHERN ZONES SHOULD RETAIN AN OFFSHORE FLOW BUT THERE
COULD BE VEERING OVER NORTHERN ZONES THAT MANAGE TO SEE FROPA.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RJD/8
SHORT TERM...DRH
LONG TERM...MBB
AVIATION...DL/8
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
852 AM CDT TUE JUL 28 2015
.UPDATE...
ISSUED AT 852 AM CDT TUE JUL 28 2015
DID A QUICK UPDATE TO THE FORECAST TO MATCH UP WITH CURRENT
CONDITIONS. CLOUDS ARE THINNING ALONG AND WEST OF THE RED RIVER
VALLEY ALREADY...AND CLOUDS EAST OF THE VALLEY SHOULD THIN OUT
BY LATER MORNING. THERE ARE STILL SOME SHOWERS ACROSS THE KBJI TO
KBDE AREA...BUT NO LONGER ANY LIGHTNING THERE. THESE SHOWERS
SHOULD SLOWLY PUSH EAST THIS MORNING TOO LEAVING MOST AREAS DRY
THE REST OF THE AFTERNOON. NOT SURE YET ABOUT ANY REDEVELOPMENT
OVER OUR MN COUNTIES THIS AFTERNOON. LATEST RAP KEEPS IT DRY WHILE
THE LATEST NAM12 SHOWS A SMALL BIT OF REDEVELOPMENT. EITHER WAY
NOT EXPECTING ANY SEVERE WEATHER FROM IT. MAIN ISSUE TODAY WILL BE
THE INCREASING WEST WINDS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 352 AM CDT TUE JUL 28 2015
150+M HEIGHT FALLS FORECAST OVER SOUTHERN MAN AND ONTARIO FOR TODAY
AND TONIGHT AS A STRONG MT UPPER LEVEL TROUGH MOVES ACROSS SOUTHERN
CANADA. SURFACE LOW PRESSURE OVER SOUTHEAST SASK FORECAST TO DEEPEN
SIGNIFICANTLY THROUGH 18Z THEN MOVE INTO NORTHERN ONTARIO BY 48
HOURS. PRECIPITABLE WATER AROUND AN INCH AND A HALF OVER THE AREA
AND OVER 2 INCHES OVER EASTERN SD. EAST-WEST CROSS SECTION INDICATES
DRIER AIR MOVES IN FROM THE WEST TODAY WITH THUNDERSTORMS OCCURRING
ALONG THE BOUNDARY. MOIST AIR SHIFTS EAST TODAY AS DRY SLOT MOVES
INTO THE AREA. EXPECT STRONGEST STORMS TO THE SOUTH...OVER SD OR ON
THE SOUTHERN END OF THE CURRENT LINE. MAY KEEP THE SAME TREND FOR
TODAY. LINE CONTINUED TO WEAKEN THIS MORNING.
MODEL SOUNDINGS INDICATE AN ADIABATIC LAYER THIS AFTERNOON AND
ESSENTIALLY THROUGH WED EVENING EXCEPTING 12Z WED. WINDS TO 60 KNOTS
IN THIS LAYER THIS AFTERNOON AND EVENING...ESPECIALLY THE NORTHWEST
ZONES. WILL ISSUE A WIND ADVISORY FOR ABOUT THE NORTHWEST HALF OF
THE FORECAST AREA. MAY NEED A HIGH WIND WARNING NORTHWEST
ZONES...WILL LET NEXT SHIFT DETERMINE IF NEEDED. WINDY YET WED
MORNING AND DECREASING THROUGH THE DAY.
SOME WRAP AROUND PRECIP EXPECTED OVER THE FAR NORTHERN ZONES TUE
NIGHT AND WED.
SHORT WAVE OVER THE EASTERN PACIFIC WILL MOVE INTO SOUTHERN CANADA
THU AFTER AND EVENING AND MAY PRODUCE PRECIP OVER NORTHERN ZONES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 352 AM CDT TUE JUL 28 2015
FOR FRI THROUGH MON...EXPECT MAINLY DRY WEATHER WITH TEMPS SLIGHTLY
BELOW NORMAL. THERE WILL BE SEVERAL WAVES IN NW FLOW ALOFT...WITH
THE BEST WAVE THIS WEEKEND. TIMING AND OVERALL COVERAGE OF ANY
CONVECTION WILL HINGE ON IF WAVES COME THROUGH AT MAX HEATING...SO
CONFIDENCE NOT HIGH ON WHAT DAY COULD PRODUCE SHOWERS/STORMS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 700 AM CDT TUE JUL 28 2015
MVFR CIGS WERE OVER THE EASTERN AND NORTHERN PARTS OF THE AREA. CIGS
WERE GENERALLY BETWEEN 10 HUNDRED AND 20 HUNDRED FT. SOME IFR CIGS
OF 4 TO 6 HUNDRED FT WAS IN THE SOUTHWEST ZONES. OTHERWISE VFR
CONDITIONS WERE OVER THE AREA. EXPECT MVFR CIGS TO SHIFT EAST THIS
MORNING. MVFR TO VFR CIGS BETWEEN 1 THOUSAND AND 4 THOUSAND FT WILL
MOVE INTO THE NORTHWEST ZONES THIS EVENING AND INTO THE NORTHERN RED
RIVER VALLEY LATER TONIGHT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 11 PM CDT THIS EVENING
FOR NDZ006>008-014>016-024-026>030-038-039-049-052-054.
MN...WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 11 PM CDT THIS EVENING
FOR MNZ001-004-005-007-008-013-014.
&&
$$
UPDATE...GODON
SHORT TERM...HOPPES
LONG TERM...DK
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1257 AM CDT TUE JUL 28 2015
.UPDATE...
ISSUED AT 1255 AM CDT TUE JUL 28 2015
HAVE TRIMMED OFF MOST OF THE WESTERN PORTIONS OF THE CONVECTIVE
WATCHES WHERE WIND/HAIL THREAT HAS DIMINISHED...KEEPING ONLY
PORTIONS OF NORTH CENTRAL NORTH DAKOTA INTO THE JAMES RIVER VALLEY
ALONG AND AHEAD OF THE ADVANCING LINE.
UPDATE ISSUED AT 1237 AM CDT TUE JUL 28 2015
FOR THIS UPDATE...HAVE REMOVED SOUTHWEST COUNTIES FROM SEVERE
THUNDERSTORM WATCH 457. COLD FRONT NOW THROUGH THE SOUTHWEST AND
PUSHING EAST. MAIN LINE OF THUNDERSTORMS NOW INTO THE JAMES RIVER
VALLEY. FOCUS AFTER THE FRONTAL PASSAGE WILL BE THE HIGH WIND
WATCH FOR LATER TUESDAY MORNING INTO TUESDAY EVENING.
UPDATE ISSUED AT 1050 PM CDT MON JUL 27 2015
COORDINATED WITH SPC AND SEVERE THUNDERSTORM WATCH 458 HAS BEEN
ISSUED UNTIL 5AM CDT TUESDAY. THIS COVERS ALL COUNTIES IN THE
BISMARCK COUNTY WARNING AREA THAT WERE NOT INCLUDED IN SEVERE
THUNDERSTORM WATCH 457. UPDATES FORTHCOMING.
UPDATE ISSUED AT 943 PM CDT MON JUL 27 2015
QUICK UPDATE TO ADD BURLEIGH AND EMMONS COUNTIES TO THE EXISTING
SEVERE THUNDERSTORM WATCH 457...WHICH CONTINUES UNTIL 3AM CDT
TUESDAY. UPDATED PRODUCTS SENT.
UPDATE ISSUED AT 643 PM CDT MON JUL 27 2015
UPDATED POPS WITH HRRR ENSEMBLE. TRIED TO CAPTURE THE HIGHER POPS
EXPECTED NEXT 6 HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 233 PM CDT MON JUL 27 2015
CONSIDERABLE SUNSHINE ALLOWING FULL HEATING ACROSS MUST OF WEST
AND CENTRAL NORTH DAKOTA THIS AFTERNOON. DEWPOINTS INTO THE MID
60S TO THE MID 70S. NAM BUFKIT SOUNDINGS HAVE 4000+ CAPE WITH
20-30 KTS BULK SHEAR ACROSS WEST AND CENTRAL NORTH DAKOTA. WAITING
FOR CAP TO ERODE.
HEAVY RAIN AMOUNTS IN THE THUNDERSTORM AREAS OF ONE TO NEARLY 2
INCHES MAINLY NORTH. ISOLATED MUCH HIGHER AMOUNTS CERTAINLY
POSSIBLE.
ON TUESDAY...EXPANDED THE HIGH WIND WATCH EAST THROUGH THE CWA.
MODELS DELAYED THE HIGHER WINDS ABOUT 3 TO 6 HOURS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 233 PM CDT MON JUL 27 2015
THE LONG TERM WILL START WITH WINDY CONDITIONS AND SCATTERED
SHOWERS TUESDAY NIGHT THROUGH WEDNESDAY MORNING.
THE DEPARTING LOW WILL PRODUCE WRAP AROUND SHOWERS...MAINLY ACROSS
NORTHERN NORTH DAKOTA. ADDITIONALLY WITH DOWNSLOPING WINDS AND
STRONG CAA WEDNESDAY LOOKS LIKE ANOTHER WINDY DAY...ALBEIT MUCH
LESS THAN TUESDAY.
THEREAFTER WE WILL SEE A TRANSITION TO NORTHWEST FLOW...WITH
RELATIVELY COOL AND DRY CONDITIONS THROUGH THE REST OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1237 AM CDT TUE JUL 28 2015
THUNDERSTORMS WITH STRONG WINDS STILL AFFECTING KMOT AND KJMS AT
THE BEGINNING OF THIS TAF PERIOD...WITH KISN/KDIK/KBIS RECEIVING
LIMITED SHOWERS AND THUNDERSTORMS. MAIN ISSUE FOR TUESDAY MORNING
THROUGH THE EVENING WILL BE THE VERY STRONG WEST WINDS...WITH THE
LATEST DATA SHOWING GUSTS TO AROUND 50KT AT ALL TERMINALS EXCEPT
KJMS...WHICH WILL SEE MAX GUSTS TO AROUND 40KT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM 10 AM CDT /9 AM MDT/ THIS MORNING THROUGH
THIS EVENING FOR NDZ001>003-009>011-017>021-031>035-040>046.
HIGH WIND WATCH FROM THIS AFTERNOON THROUGH THIS EVENING FOR
NDZ004-005-012-013-022-023-025-036-037-047-048-050-051.
&&
$$
UPDATE...JJS
SHORT TERM...WAA
LONG TERM...AJ
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1237 AM CDT TUE JUL 28 2015
.UPDATE...
ISSUED AT 1237 AM CDT TUE JUL 28 2015
FOR THIS UPDATE...HAVE REMOVED SOUTHWEST COUNTIES FROM SEVERE
THUNDERSTORM WATCH 457. COLD FRONT NOW THROUGH THE SOUTHWEST AND
PUSHING EAST. MAIN LINE OF THUNDERSTORMS NOW INTO THE JAMES RIVER
VALLEY. FOCUS AFTER THE FRONTAL PASSAGE WILL BE THE HIGH WIND
WATCH FOR LATER TUESDAY MORNING INTO TUESDAY EVENING.
UPDATE ISSUED AT 1050 PM CDT MON JUL 27 2015
COORDINATED WITH SPC AND SEVERE THUNDERSTORM WATCH 458 HAS BEEN
ISSUED UNTIL 5AM CDT TUESDAY. THIS COVERS ALL COUNTIES IN THE
BISMARCK COUNTY WARNING AREA THAT WERE NOT INCLUDED IN SEVERE
THUNDERSTORM WATCH 457. UPDATES FORTHCOMING.
UPDATE ISSUED AT 943 PM CDT MON JUL 27 2015
QUICK UPDATE TO ADD BURLEIGH AND EMMONS COUNTIES TO THE EXISTING
SEVERE THUNDERSTORM WATCH 457...WHICH CONTINUES UNTIL 3AM CDT
TUESDAY. UPDATED PRODUCTS SENT.
UPDATE ISSUED AT 643 PM CDT MON JUL 27 2015
UPDATED POPS WITH HRRR ENSEMBLE. TRIED TO CAPTURE THE HIGHER POPS
EXPECTED NEXT 6 HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 233 PM CDT MON JUL 27 2015
CONSIDERABLE SUNSHINE ALLOWING FULL HEATING ACROSS MUST OF WEST
AND CENTRAL NORTH DAKOTA THIS AFTERNOON. DEWPOINTS INTO THE MID
60S TO THE MID 70S. NAM BUFKIT SOUNDINGS HAVE 4000+ CAPE WITH
20-30 KTS BULK SHEAR ACROSS WEST AND CENTRAL NORTH DAKOTA. WAITING
FOR CAP TO ERODE.
HEAVY RAIN AMOUNTS IN THE THUNDERSTORM AREAS OF ONE TO NEARLY 2
INCHES MAINLY NORTH. ISOLATED MUCH HIGHER AMOUNTS CERTAINLY
POSSIBLE.
ON TUESDAY...EXPANDED THE HIGH WIND WATCH EAST THROUGH THE CWA.
MODELS DELAYED THE HIGHER WINDS ABOUT 3 TO 6 HOURS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 233 PM CDT MON JUL 27 2015
THE LONG TERM WILL START WITH WINDY CONDITIONS AND SCATTERED
SHOWERS TUESDAY NIGHT THROUGH WEDNESDAY MORNING.
THE DEPARTING LOW WILL PRODUCE WRAP AROUND SHOWERS...MAINLY ACROSS
NORTHERN NORTH DAKOTA. ADDITIONALLY WITH DOWNSLOPING WINDS AND
STRONG CAA WEDNESDAY LOOKS LIKE ANOTHER WINDY DAY...ALBEIT MUCH
LESS THAN TUESDAY.
THEREAFTER WE WILL SEE A TRANSITION TO NORTHWEST FLOW...WITH
RELATIVELY COOL AND DRY CONDITIONS THROUGH THE REST OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1237 AM CDT TUE JUL 28 2015
THUNDERSTORMS WITH STRONG WINDS STILL AFFECTING KMOT AND KJMS AT
THE BEGINNING OF THIS TAF PERIOD...WITH KISN/KDIK/KBIS RECEIVING
LIMITED SHOWERS AND THUNDERSTORMS. MAIN ISSUE FOR TUESDAY MORNING
THROUGH THE EVENING WILL BE THE VERY STRONG WEST WINDS...WITH THE
LATEST DATA SHOWING GUSTS TO AROUND 50KT AT ALL TERMINALS EXCEPT
KJMS...WHICH WILL SEE MAX GUSTS TO AROUND 40KT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM 10 AM CDT /9 AM MDT/ THIS MORNING THROUGH
THIS EVENING FOR NDZ001>003-009>011-017>021-031>035-040>046.
HIGH WIND WATCH FROM THIS AFTERNOON THROUGH THIS EVENING FOR
NDZ004-005-012-013-022-023-025-036-037-047-048-050-051.
&&
$$
UPDATE...KS
SHORT TERM...WAA
LONG TERM...AJ
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1144 PM CDT MON JUL 27 2015
.UPDATE...
ISSUED AT 1139 PM CDT MON JUL 27 2015
ADJUSTED POPS AS CONVECTION STILL WELL WEST OF THE FA. OTHERWISE
NO CHANGES AS WILL BE NOW BE MONITORING FOR SEVERE STORMS.
UPDATE ISSUED AT 925 PM CDT MON JUL 27 2015
CONVECTIVE EVOLUTION ACROSS WESTERN ND CONTINUES TO BE SLOW WITH
MAIN ACTION ACROSS W SD...E MT AND ALONG THE FAR SOUTHERN MB/SASK
BORDER AREA. A FEW STRONG STORMS HAVE MOVED INTO FAR S CENTRAL ND
BETWEEN DIK AND BIS AND JUST MOVING ACROSS THE MT/ND BORDER AREA.
STRONGEST SHEAR WITH WAVE OVER W SD AND E MT. BEST LOW LEVEL
FORCING STILL ALONG ND/MT BORDER AREA VCNTY SFC LOW AND ASSOCIATED
BOUNDARY. BASED ON CURRENT RADAR TRENDS CUT BACK ON POPS BUT
MAINTAINED SLIGHT CHANCES ACROSS THE FAR W CLOSE TO MIDNIGHT BUT
UNCERTAIN WITH THAT. HIGH RESOLUTION QUICK UPDATE MODELS DO NOT
BRING ANYTHING INTO THE WEST UNTIL JUST BEFORE DAY BREAK. SEVERE
THREAT ALSO SOMEWHAT IN QUESTION. INSTABILITY REMAINS HOWEVER
CONVERGENCE WITH MODEST LOW LEVEL JET NOT ALL THAT IMPRESSIVE.
MAINTAINED CURRENT POPS LATER TONIGHT BUT AGAIN SEVERE THREAT NOT
ALL THAT CLEAR.
UPDATE ISSUED AT 629 PM CDT MON JUL 27 2015
ONLY CHANGES WERE TO ADD SOME ISOLD TSRA CHANCES TO THE FAR SW FA
ALTHOUGH CURRENT CONVECTION WEAKENING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 318 PM CDT MON JUL 27 2015
RATHER WEAK SHORT WAVE OVER THE MID RED RIVER VALLEY AT MID AFTN.
AREA OF MID LEVEL ALTOCU WITH THIS INTO PARTS OF NW MN AS WELL
GFK-DTL REGION. STILL COUPLE OF SHOWERS IN THIS AREA AND WILL
CONTINUE MENTION THRU 23Z. OTHERWISE WARM AIR ALOFT SEEN ON VSBL
SAT PIX WITH LACK OF CU FROM BISMARCK AREA TO NEAR STANLEY ND TO
ESTEVAN SK. HRRR AND OTHER VARIOUS WRF MODELS QUITE SIMILAR IN
SHOWING ACTIVITY INCREASING 23Z-01Z IN ERN MT OR FAR WRN ND INTO
SE SASK AND THEN EVENTUALLY SPREADING EAST AND NORTHEAST..WITH
THREAT NOT INTO ERN ND TIL LIKELY AFTER 06Z. MOST SHORT RANGE
MODELS ALSO SO A SECOND AREA OF STORMS IN ECNTRL SD INTO CENTRAL
MN. ALL IN ALL BULK SHEAR IS PRETTY GOOD BUT MAIN MID LEVEL JET
AROUND THE BASE OF THE 500 MB LOW IS STILL WEST AND NORTHWEST OF
OUR AREA OVERNIGHT SO AT THIS POINT THE IDEA OF SEVERE OUTBREAK
FOR ERN ND/NW MN POINTS TOWARD ISOLATED AT BEST AS SOME CLUSTERS
OR A SQUALL LINE MOVES IN. COORD WITH VARIOUS OFFICES AND HAVE
SLOWED DOWN THE POPS A BIT MORE. SUNNIER AND LESS WINDY FOR
THURSDAY AS HIGH PRESSURE BUILDS IN.
FOR THURSDAY NIGHT THROUGH MONDAY...STILL EXPECTING A RIDGE TO
DEVELOP OVER THE WESTERN UNITED STATES WHILE LOW PRESSURE REMAINS
OVER HUDSON BAY. THIS WILL PUT THE FA IN NORTHWEST FLOW FOR THE
DURATION OF THE LONG TERM. THIS KEEPS THE FA IN A GENERALLY QUIET
PERIOD ALTHOUGH THERE MAY BE SOME LOW END PCPN CHANCES AT TIMES.
EXACTLY WHEN A TOUGH CALL AT THIS POINT WITH NO DECENT AGREEMENT
BETWEEN SOLUTIONS. TEMPS SHOULD REMAIN NEAR OR SLIGHT BELOW NORMAL
FOR LATE JULY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 318 PM CDT MON JUL 27 2015
ONGOING CONVECTION EXITING THE RRV 12Z TUES AND EXITING NW MN BY
MIDDAY. DRY SLOT COMING IN AND PRETTY STRONG 925 MB WINDS ON THE
SOUTH SIDE OF THE UPPER LOW MOVES INTO CNTRL ND TUES AFTN AND INTO
PARTS OF NE/ECNTRL ND LATE TUES AFTN/EARLY EVE. AT THIS
POINT...MAY FLIRT WITH HIGH WIND WARNING CRITERIA FOR A SHORT TIME
DVL BASIN WITH ADVISORY CONDITIONS FOR A FEW HOURS OTHER AREAS IN
ERN ND. NO HEADLINES WILL BE ISSUED THIS FCST AS IT WILL PAST 18Z
TUES AND GIVES MID SHIFT TIME TO ISSUE PRODUCTS AS NEEDED.
WRAPAROUND CLOUDS AND A FEW SHOWERS TO MOVE INTO NE ND/NW MN TUES
NIGHT..EXITING LAKE OF THE WOODS WED MORNING. BREEZY
WEDNESDAY WITH A MIX OF CLOUD/SUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1139 PM CDT MON JUL 27 2015
MAIN CHALLENGE WILL BE TIMING OF POTENTIAL T THROUGH TAF SITES
THEN INCREASING WINDS LATER TOMORROW AFTERNOON. AT THIS POINT FEEL
FAR HAS THE BEST POTENTIAL WITH UNCERTAINTY CONTINUING AT OTHER
SITES. LATER TOMORROW DVL BASIN WILL BE SEEING VERY STRONG WINDS
DEVELOPING WITH GUSTS HIGHER THAN 45KTS PSBL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...RIDDLE
LONG TERM...GODON/RIDDLE
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
737 PM EDT WED JUL 29 2015
.SYNOPSIS...
HEAT CONTINUES THIS AFTERNOON BEFORE STRONG A COLD FRONT ARRIVES
LATE TONIGHT. MAINLY DRY THROUGH THE WEEKEND EXCEPT FOR LOW
CHANCES ACROSS THE NORTH.
&&
.NEAR TERM /THROUGH THURSDAY/...
730 PM UPDATE...UPDATED POPS USING A BLEND OF HRRR AND WRF GUIDANCE.
THIS SPED UP THE HIGHEST POPS A BIT...AND ALSO TIGHTENED UP THE
GRADIENT ON THE BACK EDGE LATE TONIGHT INTO THURSDAY. OTHERWISE ONLY
MINIMAL CHANGES MADE.
PREVIOUS DISCUSSION... MODELS ARE IN REASONABLE AGREEMENT ON A WEAK
COLD FRONT MOVING ACROSS THE AREA LATER TONIGHT AND THURSDAY
MORNING. BACKING UP TO THIS AFTERNOON AND EARLY EVENING...SOME DRY
AIR ALOFT WILL CURTAIL CONVECTION OVER THE WESTERN HALF OF THE
AREA...WHILE MAINLY SCATTERED MOUNTAIN CONVECTION IN THE MORE DEEPER
MOISTURE WILL DISSIPATE WITH LOSS OF HEATING THIS EVENING. BETWEEN
THESE TWO FACTORS...MOST AREAS WILL REMAIN JUST BELOW HEAT ADVISORY
CRITERIA THIS AFTERNOON...BUT APPROACHING 100 DEGREES TO CONTINUE A
SPECIAL WEATHER STATEMENT FOR CAUTION.
FOR THE FRONT...EXPECT IT TO REACH THE OHIO RIVER BY 12Z...CKB-CRW
LINE BY 14Z AND THE MOUNTAINS BY 17Z. DESPITE THE LACK OF UPPER
SUPPORT...LOSS OF HEATING...AND WEAKNESS OF THE FRONT...THERE
WILL BE AT LEAST SCATTERED SHOWERS AND A FEW STORMS IN THE VERY
JUICY AIRMASS ALONG AND ESPECIALLY AHEAD OF THE FRONT OVERNIGHT
INTO THURSDAY MORNING. WILL GO WITH 30-40 POPS. MODELS INDICATE
MOST OF ANY CONVECTION WILL BE WITH A PREFRONTAL TROUGH WITH
LITTLE ACTIVITY ALONG THE COLD FRONT ITSELF. THUS...WILL TIME
CONVECTION MORE WITH THIS SURFACE TROUGH. MOST OF THE CONVECTION
BY MORNING WILL BE IN THE MOUNTAINS...AND EXITING EARLY
AFTERNOON...AND DO NOT REALLY EXPECT A WIDESPREAD STRATUS SHIELD
BEHIND THIS FRONT. NOTHING REALLY SHOWING UP AT THIS TIME BEHIND
THE APPROACHING FRONT.
FOR TEMPERATURES...WILL KEEP MINDS TONIGHT ON THE HIGHER SIDE OF
GUIDANCE...QUITE MUGGY. FOR THURSDAY...TOOK A BLEND OF THE MODELS
WHICH BRINGS MAX TEMPS BACK TO NORMAL...BUT ALSO DRIER AIR.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
SIG WX NIL...EXCEPT FOR A WEAK SURFACE TROUGH FRIDAY NIGHT WHICH
WILL BRING A CHANCE OF SHOWERS ALONG THE NORTHERN TIER OF COUNTIES
IN SOUTHEAST OHIO AND NORTH CENTRAL WEST VIRGINIA LATE FRIDAY
NIGHT AND EARLY SATURDAY. THIS WILL KEEP TEMPERATURES FROM
CLIMBING BACK TO THE 90 DEGREE MARK FOR THE LOWLANDS IN THE SHORT
TERM.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
DESPITE THE BROAD TROUGH ALOFT OVER THE AREA...ONLY SIGNIFICANT
WEATHER SYSTEM IS A COLD FRONT SLATED FOR THE TUESDAY AND TUESDAY
NIGHT TIME FRAME. WILL NEED TO WATCH THE OPERATIONAL MODELS TO SEE
IF THIS CREEPS IN EARLIER IN THE PERIOD. OTHERWISE...NORMAL TO
SLIGHTLY ABOVE NORMAL TEMPERATURES PREVAIL...WITH DRY CONDITIONS
OUTSIDE OF THE AFOREMENTIONED FRONT.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/... COLD FRONT APPROACHING
FROM THE WEST...WITH LINE OF SHOWERS AND THUNDERSTORMS AHEAD OF THE
FRONT. NEAR TERM MODELS TRY TO WEAKEN THIS ACTIVITY AS IT ENTERS
CWA...WHICH IS SUPPORTED BY CURRENT RADAR TRENDS. DUE TO THIS...DID
NOT INCLUDE ANY IFR OVERNIGHT...BUT INSTEAD KEPT A MORE GENERAL MVFR
IN SHOWERS WITH VCTS. MAY NEED TO UPDATE AS THE EVENING PROGRESSES.
ALSO SOMEWHAT UNCERTAIN ON FOG FORMATION. WITH PRECIPITATION AND
CLOUDS AROUND...WENT WITH MVFR VALLEY FOG... HOWEVER SHOULD SOME
BREAKS IN THE CLOUDS DEVELOP BEHIND THE PRECIP DENSER FOG WOULD BE
POSSIBLE.
COLD FRONT MOVE THROUGH THE WEST EARLY THURSDAY MORNING...AND THROUGH
THE MOUNTAINS BY MID AFTERNOON. HAVE SOME MVFR CIGS IN THE MOUNTAINS
TONIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS...TIMING AND INTENSITY SHOWERS AND STORMS LATE
TONIGHT INTO THURSDAY MAY VARY. FOG OCCURRENCE DEPENDS ON EXTENT
OF SHOWER ACTIVITY AND IF THERE ARE ENOUGH BREAKS IN THE CLOUDS
LATER TONIGHT.
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 21 22 23 00 01 02 03 04 05 06 07 08
EDT 1HRLY 17 18 19 20 21 22 23 00 01 02 03 04
CRW CONSISTENCY H H H H H H H H H H H M
HTS CONSISTENCY H H H H H H H H H H M M
BKW CONSISTENCY M H H H H H H H M M M M
EKN CONSISTENCY H H H H H H H H H H H M
PKB CONSISTENCY H H H H H H H H H H M M
CKB CONSISTENCY H H H H H H H H H H H M
AFTER 00Z FRIDAY...
RIVER VALLEY IFR FOG POSSIBLE EARLY FRIDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...JMV/MZ
SHORT TERM...26
LONG TERM...26/DTC
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
210 AM EDT TUE JUL 28 2015
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL MOVE SLOWLY SOUTH OF THE OHIO RIVER
TONIGHT THROUGH TUESDAY...WHILE HIGH PRESSURE MOVES ACROSS THE
GREAT LAKES. A COLD FRONT WILL PROVIDE THE FOCUS FOR THUNDERSTORM
DEVELOPMENT ON WEDNESDAY. HIGH PRESSURE AND A DRIER AIRMASS ARE
EXPECTED FOR THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
VERY HUMID AIRMASS ASSOCIATED WITH A FRONTAL BOUNDARY SITUATED
NEAR THE OHIO RIVER WILL CONTINUE TO ALLOW A FEW SHOWERS TO
DEVELOP AND POSSIBLY PERSIST THROUGH EARLY TONIGHT. SURFACE OBS
INDICATE DEW POINTS IN THE LOWER 70S FOR MOST OF THE AREA AND
ISOLATED SHOWERS ARE STILL DEVELOPING IN THOSE HIGHER DEW POINTS.
LATEST RAP INDICATES DISSIPATION OF SHOWERS AFTER MIDNIGHT. LOWER
DEW POINTS IN MID 60S OVER FAR NORTHERN COUNTIES CLOSER TO THE
CENTER OF HIGH PRESSURE SHOULD KEEP THEM FREE FROM PRECIP TONIGHT.
SLOW MOVING CELLS AND HEAVY RAIN IN AN AIRMASS CONTAINING ABOUT
1.8 INCHES PRECIPITABLE WATER MAY RESULT IN LOCALIZED HIGH WATER.
LOWS WILL VARY WITH RESPECT TO DEW POINTS AS WELL...WITH LOWS
RANGING FROM THE MID 60S FAR NORTH IN LOWER HUMIDITY...UP TO THE
LOWER 70S IN THE MOISTER AIRMASS SOUTH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
WEAKENING FRONTAL BOUNDARY SETTLING OVER KENTUCKY WILL PROVIDE
THE FOCUS FOR ISOLATED SHOWERS AND THUNDERSTORMS ON TUESDAY.
SOUTHERN LOCATIONS THAT WILL BE UNDER A PERSISTENTLY HUMID AIRMASS
SHOW THE BEST CHANCES FOR CONVECTION...AND NORTHERN LOCATIONS MAY
SEE NONE. CONVECTION SHOULD DISSIPATE TUESDAY NIGHT WITH LOSS OF
DAYTIME HEATING AND DECREASING FORCING.
KEPT HIGH TEMPERATURES SLIGHTLY BELOW GUIDANCE FOLLOWING RECENT
TRENDS...WITH HIGHS FORECAST TO BE IN THE UPPER 80S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
PROGRESSIVE MID LEVEL TROF/UPR LOW TO MOVE FROM THE NRN PLAINS/SRN
CANADA ACRS THE GREAT LAKES AT MID WEEK FLATTENING OUT THE NRN
PORTION OF THE RIDGE. THIS WILL ALLOW AN ASSOCIATED SFC COLD FRONT
TO PUSH THRU THE REGION LATE WED NIGHT/EARLY THURSDAY.
WILL CONTINUE MENTION OF LOW CHANCE POPS FOR THUNDERSTORMS WED AFTN
AS MOISTURE AND MODERATE INSTBY RETURNS. ON THE WARM SIDE OF THE
SYSTEM...WARM TEMPERATURES TO CONTINUE WEDNESDAY AHEAD OF THE FRONT
WITH HIGHS FROM THE UPPER 80S NW TO THE LOWER 90S SE.
WILL BUMP UP POPS TO HIGH CHANCE WED NIGHT WITH THE APPROACH AND
PASSAGE OF THE FRONT. MODEL SOLNS A LTL FASTER WITH THE COLD FRONTAL
PASSAGE. THEREFORE...WILL END ALL PCPN VERY EARLY IN THE SE.
AS SFC HIGH PRESSURE BEGINS TO NOSE IN THURSDAY...DRY CONDITIONS
WILL RETURN. TEMPERATURES WILL BE A LTL COOLER WITH HIGHS FROM THE
LOWER 80S NW TO THE UPPER 80S SE.
NORTHWEST FLOW ALOFT WITH SFC HIGH PRESSURE BUILDING ACRS THE REGION
LATE IN THE WEEK INTO NEXT WEEKEND. HIGH TEMPERATURES ON BOTH FRIDAY
AND SATURDAY WILL BE CLOSE TO NORMAL WITH HIGHS IN THE LOWER 80S
TO UPPER 80S.
MODEL SOLN DIFFERENCES EXIST REGARDING PCPN LATE NEXT WEEKEND
ASSOCIATED WITH SFC FRONT DROPPING INTO THE GREAT LAKES. WILL LIMIT
POPS TO SLIGHT CHANCE ACRS THE NORTH SUNDAY AFTN AND THEN BRING
CHANCE POPS CWA WIDE MONDAY. HIGHS SUNDAY AND MONDAY WILL BE CLOSE
TO NORMAL RANGING FROM THE LOWER 80S NORTH TO THE UPPER 80S SOUTH.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
WEAK FRONT HAS STALLED AROUND THE OHIO RIVER. HIGHER DEWPOINTS
POOLING AROUND THE FRONT WILL COMBINE WITH LIGHT WINDS TO PROVIDE
GOOD CONDITIONS FOR FOG DEVELOPMENT IN THE SRN TAFS. WENT LIFR VSBYS
AT KLUK...AND SOME IFR AT ILN AND MVFR AT CVG.
FOG WILL BURN OFF AFTER SUNRISE...BRINGING A RETURN TO VFR
CONDITIONS. H5 RIDGE BEGINS TO BUILD NE INTO THE REGION. THIS WILL
BEGIN TO INHIBIT THUNDERSTORM DEVELOPMENT. THERE SHOULD STILL BE
ENUF CONVERGENCE AROUND THE FRONT THAT THERE WILL BE SOME
ISOLATED CONVECTION OVER THE SRN TAF SITES CLOSER TO THE FRONTAL
BOUNDARY. ONLY MENTIONED A VCSH AT KCVG AND KLUK THIS AFTN. CONVECTION
SHOULD END AROUND SUNSET.
OUTLOOK...THUNDERSTORMS ARE POSSIBLE FROM WEDNESDAY INTO
THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO
SHORT TERM...CONIGLIO
LONG TERM...AR
AVIATION...SITES
AREA FORECAST DISCUSSION
NWS TULSA OK
1152 AM CDT TUE JUL 28 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. ISOLATED TSRA MAY
DEVELOP ACROSS PORTIONS OF NW AR THIS AFTERNOON THAT COULD AFFECT
FSM/FYV/XNA/ROG...BUT LOW ANTICIPATED COVERAGE MAKES THE OVERALL
CHANCE OF IMPACTS IS TOO LOW TO MENTION AT THIS TIME. A FRONT WILL
MOVE INTO THE AREA TOMORROW MORNING...WHICH SHOULD SWITCH WINDS TO
A NORTHERLY DIRECTION AT BVO AND PERHAPS TUL/RVS LATE IN THE
PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1008 AM CDT TUE JUL 28 2015/
..UPDATE...
DISCUSSION...
YET ANOTHER HOT AND HUMID AFTERNOON TODAY WITH UPPER RIDGE PRETTY
MUCH CENTERED OVER EASTERN OKLAHOMA AND WESTERN ARKANSAS. SURFACE
MOISTURE HAS BEEN LOATHE TO COMPLETELY MIX OUT ACROSS MOST OF THE
REGION THE LAST FEW DAYS...SO HAVE RAISED AFTERNOON DEW POINTS
JUST A BIT...WHICH OF COURSE LEADS TO A CORRESPONDING INCREASE IN
THE FORECAST MAXIMUM HEAT INDICES AS WELL. GOING HEAT ADVISORY
WILL BE SUFFICIENT SO NO HEADLINE CHANGES FORTHCOMING.
BOTH THE HRRR AND THE RAP SHOWING SOME POTENTIAL FOR ISOLATED
DIURNAL THUNDERSTORMS MUCH LIKE THE LAST FEW DAYS ACROSS PARTS OF
FAR EAST CENTRAL OKLAHOMA AND NORTHWEST ARKANSAS. THE LOCATION OF
THE UPPER HIGH SHOULD SERVE AS MORE OF AN ADDED DETERRENT TO
DEVELOPMENT...SO COVERAGE SHOULD BE EVEN LOWER THAN YESTERDAY/S
SCANT OFFERINGS...BUT CURRENTLY DO NOT THINK IT WILL SUPPRESS ALL
ACTIVITY. WILL INCLUDE A MENTION OF ISOLATED THUNDERSTORMS THIS
AFTERNOON PRIMARILY ACROSS NORTHWEST AND WEST CENTRAL ARKANSAS.
ANY THUNDERSTORMS WILL DIMINISH WITH THE LOSS OF AFTERNOON
HEATING.
UPDATES ALREADY OUT.
PREV DISCUSSION... /ISSUED 543 AM CDT TUE JUL 28 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR CONDITIONS THROUGH THE FORECAST PERIOD FOR ALL SITES WITH SOME
FAIR WEATHER CU 18-00Z. LEE TROUGH WILL RESULT IN SLIGHTLY STRONGER
LOW LEVEL FLOW THAN PAST FEW DAYS.
PREV DISCUSSION... /ISSUED 308 AM CDT TUE JUL 28 2015/
DISCUSSION...
UPPER LEVEL HIGH PRESSURE WILL REMAIN IN PLACE TODAY...AND
MOST OF TOMORROW. EXPECT AFTERNOON HIGH TEMPERATURES AND HEAT
INDEX VALUES TO RIVAL THOSE OBSERVED YESTERDAY...THEREFORE AREAL
OUTLINE OF HEAT ADVISORY WILL BE LEFT ALONE. MOST OF THE AREA WILL
SEE ANOTHER HOT DAY FOR WEDNESDAY...BUT WILL LET NEXT SHIFT
ASSESS POTENTIAL AREAL OUTLINE ADJUSTMENTS FOR WEDNESDAY. UPPER
RIDGE BEGINS TO BREAK DOWN SOME LATE WEDNESDAY...WITH LOW PRECIP
CHANCES ACROSS THE NORTHWEST ZONES WEDNESDAY NIGHT AS A WEAK
BOUNDARY APPROACHES. RIDGE WILL CONTINUE A MODEST
RETROGRADE...HOWEVER UPCOMING RAIN CHANCES WILL REMAIN LIMITED AS
THE OVERALL STRENGTH OF THE RIDGE DOESNT APPEAR TO BE
SIGNIFICANTLY COMPROMISED. SOME COOLER TEMPERATURES WILL WORK INTO
THE AT LEAST THE NORTHERN PART OF THE FA BY LATER IN THE
WEEK...WHICH WILL OFFER AT LEAST SOME AREAS A FEW DAYS OF RELIEF
FROM THE RECENT HEAT. TEMPS LOOK TO REBOUND A FEW DEGREES BY LATE
IN THE WEEKEND AND EARLY NEXT WEEK. MEAN RIDGE POSITIONING MAY
STAY FAR ENOUGH WEST...THUS KEEPING THE HOTTEST TEMPERATURES OUT
OF THE REGION.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR OKZ049-053>068-
070>076.
AR...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ARZ019-020-029.
&&
$$
SHORT TERM...22
LONG TERM....07
AVIATION...22
AREA FORECAST DISCUSSION
NWS TULSA OK
1008 AM CDT TUE JUL 28 2015
...UPDATE...
.DISCUSSION...
YET ANOTHER HOT AND HUMID AFTERNOON TODAY WITH UPPER RIDGE PRETTY
MUCH CENTERED OVER EASTERN OKLAHOMA AND WESTERN ARKANSAS. SURFACE
MOISTURE HAS BEEN LOATHE TO COMPLETELY MIX OUT ACROSS MOST OF THE
REGION THE LAST FEW DAYS...SO HAVE RAISED AFTERNOON DEW POINTS
JUST A BIT...WHICH OF COURSE LEADS TO A CORRESPONDING INCREASE IN
THE FORECAST MAXIMUM HEAT INDICES AS WELL. GOING HEAT ADVISORY
WILL BE SUFFICIENT SO NO HEADLINE CHANGES FORTHCOMING.
BOTH THE HRRR AND THE RAP SHOWING SOME POTENTIAL FOR ISOLATED
DIURNAL THUNDERSTORMS MUCH LIKE THE LAST FEW DAYS ACROSS PARTS OF
FAR EAST CENTRAL OKLAHOMA AND NORTHWEST ARKANSAS. THE LOCATION OF
THE UPPER HIGH SHOULD SERVE AS MORE OF AN ADDED DETERRENT TO
DEVELOPMENT...SO COVERAGE SHOULD BE EVEN LOWER THAN YESTERDAY/S
SCANT OFFERINGS...BUT CURRENTLY DO NOT THINK IT WILL SUPPRESS ALL
ACTIVITY. WILL INCLUDE A MENTION OF ISOLATED THUNDERSTORMS THIS
AFTERNOON PRIMARILY ACROSS NORTHWEST AND WEST CENTRAL ARKANSAS.
ANY THUNDERSTORMS WILL DIMINISH WITH THE LOSS OF AFTERNOON
HEATING.
UPDATES ALREADY OUT.
&&
.PREV DISCUSSION... /ISSUED 543 AM CDT TUE JUL 28 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR CONDITIONS THROUGH THE FORECAST PERIOD FOR ALL SITES WITH SOME
FAIR WEATHER CU 18-00Z. LEE TROUGH WILL RESULT IN SLIGHTLY STRONGER
LOW LEVEL FLOW THAN PAST FEW DAYS.
PREV DISCUSSION... /ISSUED 308 AM CDT TUE JUL 28 2015/
DISCUSSION...
UPPER LEVEL HIGH PRESSURE WILL REMAIN IN PLACE TODAY...AND
MOST OF TOMORROW. EXPECT AFTERNOON HIGH TEMPERATURES AND HEAT
INDEX VALUES TO RIVAL THOSE OBSERVED YESTERDAY...THEREFORE AREAL
OUTLINE OF HEAT ADVISORY WILL BE LEFT ALONE. MOST OF THE AREA WILL
SEE ANOTHER HOT DAY FOR WEDNESDAY...BUT WILL LET NEXT SHIFT
ASSESS POTENTIAL AREAL OUTLINE ADJUSTMENTS FOR WEDNESDAY. UPPER
RIDGE BEGINS TO BREAK DOWN SOME LATE WEDNESDAY...WITH LOW PRECIP
CHANCES ACROSS THE NORTHWEST ZONES WEDNESDAY NIGHT AS A WEAK
BOUNDARY APPROACHES. RIDGE WILL CONTINUE A MODEST
RETROGRADE...HOWEVER UPCOMING RAIN CHANCES WILL REMAIN LIMITED AS
THE OVERALL STRENGTH OF THE RIDGE DOESNT APPEAR TO BE
SIGNIFICANTLY COMPROMISED. SOME COOLER TEMPERATURES WILL WORK INTO
THE AT LEAST THE NORTHERN PART OF THE FA BY LATER IN THE
WEEK...WHICH WILL OFFER AT LEAST SOME AREAS A FEW DAYS OF RELIEF
FROM THE RECENT HEAT. TEMPS LOOK TO REBOUND A FEW DEGREES BY LATE
IN THE WEEKEND AND EARLY NEXT WEEK. MEAN RIDGE POSITIONING MAY
STAY FAR ENOUGH WEST...THUS KEEPING THE HOTTEST TEMPERATURES OUT
OF THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 97 77 96 73 / 0 0 10 10
FSM 98 76 99 75 / 20 0 10 10
MLC 97 75 98 76 / 0 0 10 10
BVO 96 73 92 69 / 0 10 10 10
FYV 93 72 94 70 / 20 0 10 10
BYV 92 73 94 69 / 20 0 10 10
MKO 96 74 97 74 / 0 0 10 10
MIO 95 73 93 69 / 0 0 10 10
F10 96 74 96 75 / 0 0 10 10
HHW 98 73 99 76 / 10 0 0 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR OKZ049-053>068-
070>076.
AR...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ARZ019-020-029.
&&
$$
SHORT TERM...22
LONG TERM....07
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
457 PM EDT TUE JUL 28 2015
.SYNOPSIS...
HIGH PRESSURE WILL PERSIST OVER THE REGION THROUGH WEDNESDAY...WITH
TEMPERATURES REMAINING ABOVE NORMAL. A WEAK COLD FRONT WILL APPROACH
THE AREA FROM THE NORTHWEST ON THURSDAY AND SETTLE JUST SOUTH OF THE
REGION ON FRIDAY. THE FRONT WILL LIKELY REMAIN STALLED JUST SOUTH OF
THE AREA THROUGH THE WEEKEND...WITH COOLER TEMPERATURES EXPECTED.
MOISTURE SHOULD INCREASINGLY RETURN NORTHWARD OVER THE FRONT THE
LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
2100 UTC UPDATE...POPS HAVE BEEN RAISED ALONG THE SOUTHERN
INTERSTATE 77 CORRIDOR PER RADAR TRENDS...AND LOWERED IN THE SC
INTERSTATES 85 CORRIDOR.
1940 UTC UPDATE...POPS AND QPF HAVE BEEN ADJUSTED TO FAVOR THE
INTERSTATE 85 CORRIDOR PER RADAR TRENDS. SKY COVER WAS UPDATED FROM
VISIBLE SATELLITE IMAGERY.
AS OF 230 PM...CONVECTION WILL CONTINUE TO DEVELOP AND DRIFT TOWARD
THE S-SE THIS AFTN...AS SUBTLE SHORTWAVE ENERGY ROUNDS THE EASTERN
PERIPHERY OF A LARGE UPPER LEVEL HIGH. THE LATEST HRRR AND THE 12Z
HIGH-RES WINDOWS ARE IN REALLY GOOD AGREEMENT ON THE TRENDS...SO I
THINK THE POP GRIDS ARE ON TRACK...SINCE THEY WERE BLENDED WITH
THOSE CAM POPS EARLIER. AS FOR SEVERE THREAT...WHILE THE STORMS HAVE
BEEN GETTING FAIRLY TALL...THE FREEZING LEVEL ABOVE 15 KFT...AND
LOW-MOD DCAPE OF 600-800 J/KG IS KEEPING THE MICROBURST THREAT IN
CHECK. THERE IS ALSO A HEAVY RAIN THREAT...AS PWATS ARE 1.8-2.0"
ACRS THE PIEDMONT...WITH SLOW STORM MOTIONS.
TONIGHT...WEAK LOW PRES OVER SOUTHERN GA...AND HIGH PRES TO THE
NORTH OF THE AREA WILL KEEP A LIGHT S/SE FLOW ACRS THE CWFA. THIS
MAY BE ENUF TO ALLOW FOR LINGERING SHRA AND A FEW EMBEDDED TSTMS
WELL PAST SUNSET. I HAVE POPS ON A SLOW DIMINISHING TREND FOR THE
TONIGHT PERIOD...TO SLGT CHC BY DAYBREAK WED. LOWS IN THE MID-UPR
60S IN THE MTNS AND LWR-MID 70S PIEDMONT.
ON WEDNESDAY...THE SYNOPTIC PATTERN WILL NOT CHANGE MUCH FROM
TODAY...WITH 500 MB HIGH PRES CONTINUING TO NOSE N AND E INTO THE
AREA FROM THE SOUTHERN PLAINS. HOWEVER...THE OP MODELS ALL RESOLVE
ANOTHER VORT MAX DRIFTING SOUTH AROUND THE RIDGE ACRS THE OHIO
VALLEY. THIS MAY HELP TRIGGER CONVECTION. THE LLVLS WILL BE
SIMILAR...WITH ELEVATED DEWPTS IN THE 70S ACRS THE PIEDMONT. CAPE
SHUD BE BACK ABOVE 1500 J/KG OR SO WITH VERY WEAK SHEAR. THE CAMS
THAT GO OUT THRU TOMORROW SHOW SIMILAR CONVECTIVE TRENDS AS TODAY.
SO WILL GO WITH HIGH-END CHC TO LIKELY POPS. SEVERE THREAT WILL
REMAIN LOW WITH MOIST MID LVLS. A SMALL EXCESSIVE RAIN THREAT WILL
CONTINUE. HIGHS AROUND PERSISTENCE IN THE 80S MTNS AND LWR-MID 90S
PIEDMONT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 140 PM TUESDAY...RETROGRESSION OF THE SUBTROPICAL HIGH INTO
THE SOUTHERN ROCKIES/HIGH PLAINS WILL OCCUR THROUGHOUT THE SHORT
TERM PERIOD...AS A SERIES OF SHORT WAVES CARVE OUT A LONG WAVE
TROUGH ACROSS MUCH OF EASTERN NORTH AMERICA BY THE END OF THE
PERIOD. THIS WILL INTRODUCE A (RATHER WEAK) FRONTAL BOUNDARY INTO
OUR AREA BY THURSDAY. MEANWHILE...SLIGHT COOLING OF THE MID-LEVEL
TEMPS AND CONTINUED HIGH DEWPOINT TEMPERATURES...ALONG WITH THE
APPEARANCE OF THE BOUNDARY SHOULD SUPPORT CONTINUED GOOD CHANCES OF
CONVECTION THURSDAY AFTERNOON...WITH PERHAPS A BETTER CHANCE FOR A
FEW PULSE-SEVERE STORMS WITHIN A MORE UNSTABLE ENVIRONMENT.
A DEVELOPING CONSENSUS IN SHORT TERM MODEL GUIDANCE INDICATES THE
UPPER TROUGH AXIS WILL BE EAST OF THE FORECAST AREA BY FRI
MORNING...TAKING THE FRONTAL BOUNDARY ALONG WITH IT. ALTHOUGH
THICKNESS VALUES WILL NOT SUPPORT AN APPRECIABLE COOL DOWN (REALLY
ONLY TAKING MAXES BACK TO NEAR-NORMAL LEVELS)...THERE WILL BE A
NOTICEABLE CHANGE IN RELATIVE HUMIDITY ACROSS MUCH OF THE AREA FRI
AFTERNOON...AS DEWPOINTS COULD MIX OUT INTO THE 50S. THE RESULT WILL
BE SMALL (AT BEST) CHANCES FOR CONVECTION FRI AFTERNOON. ALTHOUGH
SMALL POPS WILL BE ADVERTISED...MAINLY HIGHLIGHTING SOUTHERN AREAS
NEARER THE BOUNDARY...EVEN THESE MAY PROVE TO BE ON THE HIGH
SIDE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 210 PM TUESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SATURDAY WITH A BROAD UPPER TROF CENTERED OVER ONTARIO AND QUEBEC
AND VERY BROAD UPPER RIDGING IN PLACE OVER THE WESTERN CONUS. THIS
GENERAL PATTERN IS EXPECTED TO REMAIN IN PLACE THROUGH THE PERIOD
WITH SOME DEAMPLIFICATION OF THE UPPER TROF POSSIBLE TOWARDS THE END
OF THE PERIOD. AT THE SFC...RIDGING WILL SPREAD BACK OVER THE CWFA
FROM THE NW BY THE START OF THE PERIOD AND LINGER INTO EARLY NEXT
WEEK...GRADUALLY GETTING WEAKER. THE ECMWF STILL TRIES TO SPIN UP
SOME SORT OF SFC LOW TO OUR SOUTH BY THE END OF THE PERIOD...HOWEVER
THE GFS APPEARS LESS BULLISH ON LOW DEVELOPMENT NOW THAN IT HAS OVER
THE PAST COUPLE OF DAYS. ALSO OF NOTE...THE LONG RANGE MODEL
GUIDANCE IS NOW KEEPING THE PLUME OF DEEPER LYR MOISTURE FARTHER
SOUTH AND EAST COMPARED TO PREVIOUS GUIDANCE. THIS WILL ALLOW FOR
LOWER OVERALL POPS FOR MOST OF THE PERIOD. AS FOR THE SENSIBLE
FCST...WE CAN EXPECT MOSTLY DIURNAL CHANCES FOR SCT CONVECTION EACH
DAY/EVENING WITH THE BEST CHANCES OVER THE SE ZONES. TEMPS WILL
START OUT RIGHT AROUND NORMAL AND REMAIN NEAR NORMAL THROUGH THE
PERIOD.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
AT KCLT...CONVECTION IS DEVELOPING QUICKLY EARLY THIS AFTN ACRS THE
AREA...WITH SEVERAL SLOW-MOVING SHRA JUST EAST OF THE TERMINAL AT
TIME OF 18Z TAF ISSUANCE. SO WILL START OUT WITH A VCSH AND TEMPO
FOR TS FROM 18-21Z. FROM THERE...THE HIGH-RES MODELS KEEP ISOLATED
TO SCATTERED CONVECTION LINGERING AROUND THE AREA WELL PAST SUNSET.
FOR SIMPLICITY...WILL KEEP OUT MENTION BEYOND 23Z.
OTHERWISE...TONIGHT WILL BE SIMILAR TO LAST NIGHT...WITH PLENTY OF
MID AND HIGH CLOUDS AND LIGHT SE WIND. GUIDANCE IS MIXED ON MVFR
STRATUS POTENTIAL. WILL MENTION SCT015 FOR NOW TO SHOW THE TREND.
ELSEWHERE...THE BLUE RIDGE HAS REALLY LIT UP ON RADAR OVER THE LAST
HOUR...WITH CONVECTION DRIFTING TO THE SOUTH. KGSP AND KGMU LOOK TO
HAVE THE BEST SHOT OF DIRECT HIT BY TSRA IN THE NEXT COUPLE HOURS.
ALL SITES WILL HAVE CONVECTION AROUND...SO WILL GO WITH VCTS AND
TEMPO FOR THE 18-21Z TIME FRAME. AS WITH KCLT ABOVE...GUIDANCE KEEPS
LINGERING CONVECTION BEYOND SUNSET. HOWEVER...OVERALL COVERAGE SHUD
CONTINUE TO DECREASE THRU THE NIGHT. PLENTY OF MOISTURE IN
PLACE...SO POTENTIAL FOR PATCHY FOG AND MVFR OR LOWER STRATUS.
CONFIDENCE ON EXACT IMPACTS IS LOW...BUT WILL GO WITH SIMILAR
TIMELINE AS WHAT OCCURRED LAST NIGHT.
KAVL AND KHKY MAY SEE VLIFR TO LIFR CONDITIONS THROUGH
MID MORNING. ELSEWHERE...MVFR CEILINGS MAY LINGER AT KGSP AND
DEVELOP AT KGMU DURING THE EARLY DAYLIGHT HOURS. THE AFTERNOON
APPROACH OF A WEAK MID LEVEL DISTURBANCE SHOULD YIELD A ROUND OF
SHRA/TSRA LATE THIS AFTERNOON AND EVENING. I WILL INCLUDE A PROB30
OR TEMPO IN EACH TAF...GENERALLY BETWEEN 20Z TO 24Z. MTN MVFR
CEILINGS MAY REDEVELOP LATE TONIGHT...ESPECIALLY OVER AREAS THAT SEE
RAIN THIS AFTERNOON AND EVENING.
OUTLOOK...A MID LEVEL RIDGE WILL REMAIN ACROSS THE WESTERN CAROLINAS
THROUGH MID WEEK. A LONGWAVE TROUGH WILL AMPLIFY ACROSS THE ATLANTIC
STATE LATE IN THE WEEK...WITH THE LIKELY PASSAGE OF A COLD FRONT ON
FRIDAY. THE POTENTIAL FOR CONVECTION WILL INCREASE EACH DAY THIS
WEEK.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 80% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 86% HIGH 95%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK/JAT
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
456 PM EDT TUE JUL 28 2015
.SYNOPSIS...
HIGH PRESSURE WILL PERSIST OVER THE REGION THROUGH WEDNESDAY...WITH
TEMPERATURES REMAINING ABOVE NORMAL. A WEAK COLD FRONT WILL APPROACH
THE AREA FROM THE NORTHWEST ON THURSDAY AND SETTLE JUST SOUTH OF THE
REGION ON FRIDAY. THE FRONT WILL LIKELY REMAIN STALLED JUST SOUTH OF
THE AREA THROUGH THE WEEKEND...WITH COOLER TEMPERATURES EXPECTED.
MOISTURE SHOULD INCREASINGLY RETURN NORTHWARD OVER THE FRONT THE
LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
2100 UTC UPDATE...POPS HAVE BEEN RAISED ALONG THE SOUTHERN
INTERSTATE 77 CORRIDOR PER RADAR TRENDS...AND LOWERED IN THE SC
INTERSTATES 85 CORRDIOR.
1940 UTC UPDATE...POPS AND QPF HAVE BEEN ADJUSTED TO FAVOR THE
INTERSTATE 85 CORRIDOR PER RADAR TRENDS. SKY COVER WAS UPDATED FROM
VISIBLE SATELLITE IMAGERY.
AS OF 230 PM...CONVECTION WILL CONTINUE TO DEVELOP AND DRIFT TOWARD
THE S-SE THIS AFTN...AS SUBTLE SHORTWAVE ENERGY ROUNDS THE EASTERN
PERIPHERY OF A LARGE UPPER LEVEL HIGH. THE LATEST HRRR AND THE 12Z
HIGH-RES WINDOWS ARE IN REALLY GOOD AGREEMENT ON THE TRENDS...SO I
THINK THE POP GRIDS ARE ON TRACK...SINCE THEY WERE BLENDED WITH
THOSE CAM POPS EARLIER. AS FOR SEVERE THREAT...WHILE THE STORMS HAVE
BEEN GETTING FAIRLY TALL...THE FREEZING LEVEL ABOVE 15 KFT...AND
LOW-MOD DCAPE OF 600-800 J/KG IS KEEPING THE MICROBURST THREAT IN
CHECK. THERE IS ALSO A HEAVY RAIN THREAT...AS PWATS ARE 1.8-2.0"
ACRS THE PIEDMONT...WITH SLOW STORM MOTIONS.
TONIGHT...WEAK LOW PRES OVER SOUTHERN GA...AND HIGH PRES TO THE
NORTH OF THE AREA WILL KEEP A LIGHT S/SE FLOW ACRS THE CWFA. THIS
MAY BE ENUF TO ALLOW FOR LINGERING SHRA AND A FEW EMBEDDED TSTMS
WELL PAST SUNSET. I HAVE POPS ON A SLOW DIMINISHING TREND FOR THE
TONIGHT PERIOD...TO SLGT CHC BY DAYBREAK WED. LOWS IN THE MID-UPR
60S IN THE MTNS AND LWR-MID 70S PIEDMONT.
ON WEDNESDAY...THE SYNOPTIC PATTERN WILL NOT CHANGE MUCH FROM
TODAY...WITH 500 MB HIGH PRES CONTINUING TO NOSE N AND E INTO THE
AREA FROM THE SOUTHERN PLAINS. HOWEVER...THE OP MODELS ALL RESOLVE
ANOTHER VORT MAX DRIFTING SOUTH AROUND THE RIDGE ACRS THE OHIO
VALLEY. THIS MAY HELP TRIGGER CONVECTION. THE LLVLS WILL BE
SIMILAR...WITH ELEVATED DEWPTS IN THE 70S ACRS THE PIEDMONT. CAPE
SHUD BE BACK ABOVE 1500 J/KG OR SO WITH VERY WEAK SHEAR. THE CAMS
THAT GO OUT THRU TOMORROW SHOW SIMILAR CONVECTIVE TRENDS AS TODAY.
SO WILL GO WITH HIGH-END CHC TO LIKELY POPS. SEVERE THREAT WILL
REMAIN LOW WITH MOIST MID LVLS. A SMALL EXCESSIVE RAIN THREAT WILL
CONTINUE. HIGHS AROUND PERSISTENCE IN THE 80S MTNS AND LWR-MID 90S
PIEDMONT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 140 PM TUESDAY...RETROGRESSION OF THE SUBTROPICAL HIGH INTO
THE SOUTHERN ROCKIES/HIGH PLAINS WILL OCCUR THROUGHOUT THE SHORT
TERM PERIOD...AS A SERIES OF SHORT WAVES CARVE OUT A LONG WAVE
TROUGH ACROSS MUCH OF EASTERN NORTH AMERICA BY THE END OF THE
PERIOD. THIS WILL INTRODUCE A (RATHER WEAK) FRONTAL BOUNDARY INTO
OUR AREA BY THURSDAY. MEANWHILE...SLIGHT COOLING OF THE MID-LEVEL
TEMPS AND CONTINUED HIGH DEWPOINT TEMPERATURES...ALONG WITH THE
APPEARANCE OF THE BOUNDARY SHOULD SUPPORT CONTINUED GOOD CHANCES OF
CONVECTION THURSDAY AFTERNOON...WITH PERHAPS A BETTER CHANCE FOR A
FEW PULSE-SEVERE STORMS WITHIN A MORE UNSTABLE ENVIRONMENT.
A DEVELOPING CONSENSUS IN SHORT TERM MODEL GUIDANCE INDICATES THE
UPPER TROUGH AXIS WILL BE EAST OF THE FORECAST AREA BY FRI
MORNING...TAKING THE FRONTAL BOUNDARY ALONG WITH IT. ALTHOUGH
THICKNESS VALUES WILL NOT SUPPORT AN APPRECIABLE COOL DOWN (REALLY
ONLY TAKING MAXES BACK TO NEAR-NORMAL LEVELS)...THERE WILL BE A
NOTICEABLE CHANGE IN RELATIVE HUMIDITY ACROSS MUCH OF THE AREA FRI
AFTERNOON...AS DEWPOINTS COULD MIX OUT INTO THE 50S. THE RESULT WILL
BE SMALL (AT BEST) CHANCES FOR CONVECTION FRI AFTERNOON. ALTHOUGH
SMALL POPS WILL BE ADVERTISED...MAINLY HIGHLIGHTING SOUTHERN AREAS
NEARER THE BOUNDARY...EVEN THESE MAY PROVE TO BE ON THE HIGH
SIDE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 210 PM TUESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SATURDAY WITH A BROAD UPPER TROF CENTERED OVER ONTARIO AND QUEBEC
AND VERY BROAD UPPER RIDGING IN PLACE OVER THE WESTERN CONUS. THIS
GENERAL PATTERN IS EXPECTED TO REMAIN IN PLACE THROUGH THE PERIOD
WITH SOME DEAMPLIFICATION OF THE UPPER TROF POSSIBLE TOWARDS THE END
OF THE PERIOD. AT THE SFC...RIDGING WILL SPREAD BACK OVER THE CWFA
FROM THE NW BY THE START OF THE PERIOD AND LINGER INTO EARLY NEXT
WEEK...GRADUALLY GETTING WEAKER. THE ECMWF STILL TRIES TO SPIN UP
SOME SORT OF SFC LOW TO OUR SOUTH BY THE END OF THE PERIOD...HOWEVER
THE GFS APPEARS LESS BULLISH ON LOW DEVELOPMENT NOW THAN IT HAS OVER
THE PAST COUPLE OF DAYS. ALSO OF NOTE...THE LONG RANGE MODEL
GUIDANCE IS NOW KEEPING THE PLUME OF DEEPER LYR MOISTURE FARTHER
SOUTH AND EAST COMPARED TO PREVIOUS GUIDANCE. THIS WILL ALLOW FOR
LOWER OVERALL POPS FOR MOST OF THE PERIOD. AS FOR THE SENSIBLE
FCST...WE CAN EXPECT MOSTLY DIURNAL CHANCES FOR SCT CONVECTION EACH
DAY/EVENING WITH THE BEST CHANCES OVER THE SE ZONES. TEMPS WILL
START OUT RIGHT AROUND NORMAL AND REMAIN NEAR NORMAL THROUGH THE
PERIOD.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
AT KCLT...CONVECTION IS DEVELOPING QUICKLY EARLY THIS AFTN ACRS THE
AREA...WITH SEVERAL SLOW-MOVING SHRA JUST EAST OF THE TERMINAL AT
TIME OF 18Z TAF ISSUANCE. SO WILL START OUT WITH A VCSH AND TEMPO
FOR TS FROM 18-21Z. FROM THERE...THE HIGH-RES MODELS KEEP ISOLATED
TO SCATTERED CONVECTION LINGERING AROUND THE AREA WELL PAST SUNSET.
FOR SIMPLICITY...WILL KEEP OUT MENTION BEYOND 23Z.
OTHERWISE...TONIGHT WILL BE SIMILAR TO LAST NIGHT...WITH PLENTY OF
MID AND HIGH CLOUDS AND LIGHT SE WIND. GUIDANCE IS MIXED ON MVFR
STRATUS POTENTIAL. WILL MENTION SCT015 FOR NOW TO SHOW THE TREND.
ELSEWHERE...THE BLUE RIDGE HAS REALLY LIT UP ON RADAR OVER THE LAST
HOUR...WITH CONVECTION DRIFTING TO THE SOUTH. KGSP AND KGMU LOOK TO
HAVE THE BEST SHOT OF DIRECT HIT BY TSRA IN THE NEXT COUPLE HOURS.
ALL SITES WILL HAVE CONVECTION AROUND...SO WILL GO WITH VCTS AND
TEMPO FOR THE 18-21Z TIME FRAME. AS WITH KCLT ABOVE...GUIDANCE KEEPS
LINGERING CONVECTION BEYOND SUNSET. HOWEVER...OVERALL COVERAGE SHUD
CONTINUE TO DECREASE THRU THE NIGHT. PLENTY OF MOISTURE IN
PLACE...SO POTENTIAL FOR PATCHY FOG AND MVFR OR LOWER STRATUS.
CONFIDENCE ON EXACT IMPACTS IS LOW...BUT WILL GO WITH SIMILAR
TIMELINE AS WHAT OCCURRED LAST NIGHT.
KAVL AND KHKY MAY SEE VLIFR TO LIFR CONDITIONS THROUGH
MID MORNING. ELSEWHERE...MVFR CEILINGS MAY LINGER AT KGSP AND
DEVELOP AT KGMU DURING THE EARLY DAYLIGHT HOURS. THE AFTERNOON
APPROACH OF A WEAK MID LEVEL DISTURBANCE SHOULD YIELD A ROUND OF
SHRA/TSRA LATE THIS AFTERNOON AND EVENING. I WILL INCLUDE A PROB30
OR TEMPO IN EACH TAF...GENERALLY BETWEEN 20Z TO 24Z. MTN MVFR
CEILINGS MAY REDEVELOP LATE TONIGHT...ESPECIALLY OVER AREAS THAT SEE
RAIN THIS AFTERNOON AND EVENING.
OUTLOOK...A MID LEVEL RIDGE WILL REMAIN ACROSS THE WESTERN CAROLINAS
THROUGH MID WEEK. A LONGWAVE TROUGH WILL AMPLIFY ACROSS THE ATLANTIC
STATE LATE IN THE WEEK...WITH THE LIKELY PASSAGE OF A COLD FRONT ON
FRIDAY. THE POTENTIAL FOR CONVECTION WILL INCREASE EACH DAY THIS
WEEK.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 80% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 86% HIGH 95%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK/JAT
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
338 PM EDT TUE JUL 28 2015
.SYNOPSIS...
HIGH PRESSURE WILL PERSIST OVER THE REGION THROUGH WEDNESDAY...WITH
TEMPERATURES REMAINING ABOVE NORMAL. A WEAK COLD FRONT WILL APPROACH
THE AREA FROM THE NORTHWEST ON THURSDAY AND SETTLE JUST SOUTH OF THE
REGION ON FRIDAY. THE FRONT WILL LIKELY REMAIN STALLED JUST SOUTH OF
THE AREA THROUGH THE WEEKEND...WITH COOLER TEMPERATURES EXPECTED.
MOISTURE SHOULD INCREASINGLY RETURN NORTHWARD OVER THE FRONT THE
LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
1940 UTC UPDATE...POPS AND QPF HAVE BEEN ADJUSTED TO FAVOR THE
INTERSTATE 85 CORRIDOR PER RADAR TRENDS. SKY COVER WAS UPDATED FROM
VISIBLE SATELLITE IMAGERY.
AS OF 230 PM...CONVECTION WILL CONTINUE TO DEVELOP AND DRIFT TOWARD
THE S-SE THIS AFTN...AS SUBTLE SHORTWAVE ENERGY ROUNDS THE EASTERN
PERIPHERY OF A LARGE UPPER LEVEL HIGH. THE LATEST HRRR AND THE 12Z
HIGH-RES WINDOWS ARE IN REALLY GOOD AGREEMENT ON THE TRENDS...SO I
THINK THE POP GRIDS ARE ON TRACK...SINCE THEY WERE BLENDED WITH
THOSE CAM POPS EARLIER. AS FOR SEVERE THREAT...WHILE THE STORMS HAVE
BEEN GETTING FAIRLY TALL...THE FREEZING LEVEL ABOVE 15 KFT...AND
LOW-MOD DCAPE OF 600-800 J/KG IS KEEPING THE MICROBURST THREAT IN
CHECK. THERE IS ALSO A HEAVY RAIN THREAT...AS PWATS ARE 1.8-2.0"
ACRS THE PIEDMONT...WITH SLOW STORM MOTIONS.
TONIGHT...WEAK LOW PRES OVER SOUTHERN GA...AND HIGH PRES TO THE
NORTH OF THE AREA WILL KEEP A LIGHT S/SE FLOW ACRS THE CWFA. THIS
MAY BE ENUF TO ALLOW FOR LINGERING SHRA AND A FEW EMBEDDED TSTMS
WELL PAST SUNSET. I HAVE POPS ON A SLOW DIMINISHING TREND FOR THE
TONIGHT PERIOD...TO SLGT CHC BY DAYBREAK WED. LOWS IN THE MID-UPR
60S IN THE MTNS AND LWR-MID 70S PIEDMONT.
ON WEDNESDAY...THE SYNOPTIC PATTERN WILL NOT CHANGE MUCH FROM
TODAY...WITH 500 MB HIGH PRES CONTINUING TO NOSE N AND E INTO THE
AREA FROM THE SOUTHERN PLAINS. HOWEVER...THE OP MODELS ALL RESOLVE
ANOTHER VORT MAX DRIFTING SOUTH AROUND THE RIDGE ACRS THE OHIO
VALLEY. THIS MAY HELP TRIGGER CONVECTION. THE LLVLS WILL BE
SIMILAR...WITH ELEVATED DEWPTS IN THE 70S ACRS THE PIEDMONT. CAPE
SHUD BE BACK ABOVE 1500 J/KG OR SO WITH VERY WEAK SHEAR. THE CAMS
THAT GO OUT THRU TOMORROW SHOW SIMILAR CONVECTIVE TRENDS AS TODAY.
SO WILL GO WITH HIGH-END CHC TO LIKELY POPS. SEVERE THREAT WILL
REMAIN LOW WITH MOIST MID LVLS. A SMALL EXCESSIVE RAIN THREAT WILL
CONTINUE. HIGHS AROUND PERSISTENCE IN THE 80S MTNS AND LWR-MID 90S
PIEDMONT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 140 PM TUESDAY...RETROGRESSION OF THE SUBTROPICAL HIGH INTO
THE SOUTHERN ROCKIES/HIGH PLAINS WILL OCCUR THROUGHOUT THE SHORT
TERM PERIOD...AS A SERIES OF SHORT WAVES CARVE OUT A LONG WAVE
TROUGH ACROSS MUCH OF EASTERN NORTH AMERICA BY THE END OF THE
PERIOD. THIS WILL INTRODUCE A (RATHER WEAK) FRONTAL BOUNDARY INTO
OUR AREA BY THURSDAY. MEANWHILE...SLIGHT COOLING OF THE MID-LEVEL
TEMPS AND CONTINUED HIGH DEWPOINT TEMPERATURES...ALONG WITH THE
APPEARANCE OF THE BOUNDARY SHOULD SUPPORT CONTINUED GOOD CHANCES OF
CONVECTION THURSDAY AFTERNOON...WITH PERHAPS A BETTER CHANCE FOR A
FEW PULSE-SEVERE STORMS WITHIN A MORE UNSTABLE ENVIRONMENT.
A DEVELOPING CONSENSUS IN SHORT TERM MODEL GUIDANCE INDICATES THE
UPPER TROUGH AXIS WILL BE EAST OF THE FORECAST AREA BY FRI
MORNING...TAKING THE FRONTAL BOUNDARY ALONG WITH IT. ALTHOUGH
THICKNESS VALUES WILL NOT SUPPORT AN APPRECIABLE COOL DOWN (REALLY
ONLY TAKING MAXES BACK TO NEAR-NORMAL LEVELS)...THERE WILL BE A
NOTICEABLE CHANGE IN RELATIVE HUMIDITY ACROSS MUCH OF THE AREA FRI
AFTERNOON...AS DEWPOINTS COULD MIX OUT INTO THE 50S. THE RESULT WILL
BE SMALL (AT BEST) CHANCES FOR CONVECTION FRI AFTERNOON. ALTHOUGH
SMALL POPS WILL BE ADVERTISED...MAINLY HIGHLIGHTING SOUTHERN AREAS
NEARER THE BOUNDARY...EVEN THESE MAY PROVE TO BE ON THE HIGH
SIDE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 210 PM TUESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SATURDAY WITH A BROAD UPPER TROF CENTERED OVER ONTARIO AND QUEBEC
AND VERY BROAD UPPER RIDGING IN PLACE OVER THE WESTERN CONUS. THIS
GENERAL PATTERN IS EXPECTED TO REMAIN IN PLACE THROUGH THE PERIOD
WITH SOME DEAMPLIFICATION OF THE UPPER TROF POSSIBLE TOWARDS THE END
OF THE PERIOD. AT THE SFC...RIDGING WILL SPREAD BACK OVER THE CWFA
FROM THE NW BY THE START OF THE PERIOD AND LINGER INTO EARLY NEXT
WEEK...GRADUALLY GETTING WEAKER. THE ECMWF STILL TRIES TO SPIN UP
SOME SORT OF SFC LOW TO OUR SOUTH BY THE END OF THE PERIOD...HOWEVER
THE GFS APPEARS LESS BULLISH ON LOW DEVELOPMENT NOW THAN IT HAS OVER
THE PAST COUPLE OF DAYS. ALSO OF NOTE...THE LONG RANGE MODEL
GUIDANCE IS NOW KEEPING THE PLUME OF DEEPER LYR MOISTURE FARTHER
SOUTH AND EAST COMPARED TO PREVIOUS GUIDANCE. THIS WILL ALLOW FOR
LOWER OVERALL POPS FOR MOST OF THE PERIOD. AS FOR THE SENSIBLE
FCST...WE CAN EXPECT MOSTLY DIURNAL CHANCES FOR SCT CONVECTION EACH
DAY/EVENING WITH THE BEST CHANCES OVER THE SE ZONES. TEMPS WILL
START OUT RIGHT AROUND NORMAL AND REMAIN NEAR NORMAL THROUGH THE
PERIOD.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
AT KCLT...CONVECTION IS DEVELOPING QUICKLY EARLY THIS AFTN ACRS THE
AREA...WITH SEVERAL SLOW-MOVING SHRA JUST EAST OF THE TERMINAL AT
TIME OF 18Z TAF ISSUANCE. SO WILL START OUT WITH A VCSH AND TEMPO
FOR TS FROM 18-21Z. FROM THERE...THE HIGH-RES MODELS KEEP ISOLATED
TO SCATTERED CONVECTION LINGERING AROUND THE AREA WELL PAST SUNSET.
FOR SIMPLICITY...WILL KEEP OUT MENTION BEYOND 23Z.
OTHERWISE...TONIGHT WILL BE SIMILAR TO LAST NIGHT...WITH PLENTY OF
MID AND HIGH CLOUDS AND LIGHT SE WIND. GUIDANCE IS MIXED ON MVFR
STRATUS POTENTIAL. WILL MENTION SCT015 FOR NOW TO SHOW THE TREND.
ELSEWHERE...THE BLUE RIDGE HAS REALLY LIT UP ON RADAR OVER THE LAST
HOUR...WITH CONVECTION DRIFTING TO THE SOUTH. KGSP AND KGMU LOOK TO
HAVE THE BEST SHOT OF DIRECT HIT BY TSRA IN THE NEXT COUPLE HOURS.
ALL SITES WILL HAVE CONVECTION AROUND...SO WILL GO WITH VCTS AND
TEMPO FOR THE 18-21Z TIME FRAME. AS WITH KCLT ABOVE...GUIDANCE KEEPS
LINGERING CONVECTION BEYOND SUNSET. HOWEVER...OVERALL COVERAGE SHUD
CONTINUE TO DECREASE THRU THE NIGHT. PLENTY OF MOISTURE IN
PLACE...SO POTENTIAL FOR PATCHY FOG AND MVFR OR LOWER STRATUS.
CONFIDENCE ON EXACT IMPACTS IS LOW...BUT WILL GO WITH SIMILAR
TIMELINE AS WHAT OCCURRED LAST NIGHT.
KAVL AND KHKY MAY SEE VLIFR TO LIFR CONDITIONS THROUGH
MID MORNING. ELSEWHERE...MVFR CEILINGS MAY LINGER AT KGSP AND
DEVELOP AT KGMU DURING THE EARLY DAYLIGHT HOURS. THE AFTERNOON
APPROACH OF A WEAK MID LEVEL DISTURBANCE SHOULD YIELD A ROUND OF
SHRA/TSRA LATE THIS AFTERNOON AND EVENING. I WILL INCLUDE A PROB30
OR TEMPO IN EACH TAF...GENERALLY BETWEEN 20Z TO 24Z. MTN MVFR
CEILINGS MAY REDEVELOP LATE TONIGHT...ESPECIALLY OVER AREAS THAT SEE
RAIN THIS AFTERNOON AND EVENING.
OUTLOOK...A MID LEVEL RIDGE WILL REMAIN ACROSS THE WESTERN CAROLINAS
THROUGH MID WEEK. A LONGWAVE TROUGH WILL AMPLIFY ACROSS THE ATLANTIC
STATE LATE IN THE WEEK...WITH THE LIKELY PASSAGE OF A COLD FRONT ON
FRIDAY. THE POTENTIAL FOR CONVECTION WILL INCREASE EACH DAY THIS
WEEK.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT HIGH 100% HIGH 100% HIGH 90% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 93%
KAVL HIGH 100% HIGH 100% HIGH 88% HIGH 93%
KHKY HIGH 100% HIGH 100% HIGH 96% HIGH 96%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK/JAT
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
243 PM EDT TUE JUL 28 2015
.SYNOPSIS...
HIGH PRESSURE WILL PERSIST OVER THE REGION THROUGH WEDNESDAY...WITH
TEMPERATURES REMAINING ABOVE NORMAL. A WEAK COLD FRONT WILL APPROACH
THE AREA FROM THE NORTHWEST ON THURSDAY AND SETTLE JUST SOUTH OF THE
REGION ON FRIDAY. THE FRONT WILL LIKELY REMAIN STALLED JUST SOUTH OF
THE AREA THROUGH THE WEEKEND...WITH COOLER TEMPERATURES EXPECTED.
MOISTURE SHOULD INCREASINGLY RETURN NORTHWARD OVER THE FRONT THE
LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 230 PM...CONVECTION WILL CONTINUE TO DEVELOP AND DRIFT TOWARD
THE S-SE THIS AFTN...AS SUBTLE SHORTWAVE ENERGY ROUNDS THE EASTERN
PERIPHERY OF A LARGE UPPER LEVEL HIGH. THE LATEST HRRR AND THE 12Z
HIGH-RES WINDOWS ARE IN REALLY GOOD AGREEMENT ON THE TRENDS...SO I
THINK THE POP GRIDS ARE ON TRACK...SINCE THEY WERE BLENDED WITH
THOSE CAM POPS EARLIER. AS FOR SEVERE THREAT...WHILE THE STORMS HAVE
BEEN GETTING FAIRLY TALL...THE FREEZING LEVEL ABOVE 15 KFT...AND
LOW-MOD DCAPE OF 600-800 J/KG IS KEEPING THE MICROBURST THREAT IN
CHECK. THERE IS ALSO A HEAVY RAIN THREAT...AS PWATS ARE 1.8-2.0"
ACRS THE PIEDMONT...WITH SLOW STORM MOTIONS.
TONIGHT...WEAK LOW PRES OVER SOUTHERN GA...AND HIGH PRES TO THE
NORTH OF THE AREA WILL KEEP A LIGHT S/SE FLOW ACRS THE CWFA. THIS
MAY BE ENUF TO ALLOW FOR LINGERING SHRA AND A FEW EMBEDDED TSTMS
WELL PAST SUNSET. I HAVE POPS ON A SLOW DIMINISHING TREND FOR THE
TONIGHT PERIOD...TO SLGT CHC BY DAYBREAK WED. LOWS IN THE MID-UPR
60S IN THE MTNS AND LWR-MID 70S PIEDMONT.
ON WEDNESDAY...THE SYNOPTIC PATTERN WILL NOT CHANGE MUCH FROM
TODAY...WITH 500 MB HIGH PRES CONTINUING TO NOSE N AND E INTO THE
AREA FROM THE SOUTHERN PLAINS. HOWEVER...THE OP MODELS ALL RESOLVE
ANOTHER VORT MAX DRIFTING SOUTH AROUND THE RIDGE ACRS THE OHIO
VALLEY. THIS MAY HELP TRIGGER CONVECTION. THE LLVLS WILL BE
SIMILAR...WITH ELEVATED DEWPTS IN THE 70S ACRS THE PIEDMONT. CAPE
SHUD BE BACK ABOVE 1500 J/KG OR SO WITH VERY WEAK SHEAR. THE CAMS
THAT GO OUT THRU TOMORROW SHOW SIMILAR CONVECTIVE TRENDS AS TODAY.
SO WILL GO WITH HIGH-END CHC TO LIKELY POPS. SEVERE THREAT WILL
REMAIN LOW WITH MOIST MID LVLS. A SMALL EXCESSIVE RAIN THREAT WILL
CONTINUE. HIGHS AROUND PERSISTENCE IN THE 80S MTNS AND LWR-MID 90S
PIEDMONT.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 140 PM TUESDAY...RETROGRESSION OF THE SUBTROPICAL HIGH INTO
THE SOUTHERN ROCKIES/HIGH PLAINS WILL OCCUR THROUGHOUT THE SHORT
TERM PERIOD...AS A SERIES OF SHORT WAVES CARVE OUT A LONG WAVE
TROUGH ACROSS MUCH OF EASTERN NORTH AMERICA BY THE END OF THE
PERIOD. THIS WILL INTRODUCE A (RATHER WEAK) FRONTAL BOUNDARY INTO
OUR AREA BY THURSDAY. MEANWHILE...SLIGHT COOLING OF THE MID-LEVEL
TEMPS AND CONTINUED HIGH DEWPOINT TEMPERATURES...ALONG WITH THE
APPEARANCE OF THE BOUNDARY SHOULD SUPPORT CONTINUED GOOD CHANCES OF
CONVECTION THURSDAY AFTERNOON...WITH PERHAPS A BETTER CHANCE FOR A
FEW PULSE-SEVERE STORMS WITHIN A MORE UNSTABLE ENVIRONMENT.
A DEVELOPING CONSENSUS IN SHORT TERM MODEL GUIDANCE INDICATES THE
UPPER TROUGH AXIS WILL BE EAST OF THE FORECAST AREA BY FRI
MORNING...TAKING THE FRONTAL BOUNDARY ALONG WITH IT. ALTHOUGH
THICKNESS VALUES WILL NOT SUPPORT AN APPRECIABLE COOL DOWN (REALLY
ONLY TAKING MAXES BACK TO NEAR-NORMAL LEVELS)...THERE WILL BE A
NOTICEABLE CHANGE IN RELATIVE HUMIDITY ACROSS MUCH OF THE AREA FRI
AFTERNOON...AS DEWPOINTS COULD MIX OUT INTO THE 50S. THE RESULT WILL
BE SMALL (AT BEST) CHANCES FOR CONVECTION FRI AFTERNOON. ALTHOUGH
SMALL POPS WILL BE ADVERTISED...MAINLY HIGHLIGHTING SOUTHERN AREAS
NEARER THE BOUNDARY...EVEN THESE MAY PROVE TO BE ON THE HIGH
SIDE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 210 PM TUESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
SATURDAY WITH A BROAD UPPER TROF CENTERED OVER ONTARIO AND QUEBEC
AND VERY BROAD UPPER RIDGING IN PLACE OVER THE WESTERN CONUS. THIS
GENERAL PATTERN IS EXPECTED TO REMAIN IN PLACE THROUGH THE PERIOD
WITH SOME DEAMPLIFICATION OF THE UPPER TROF POSSIBLE TOWARDS THE END
OF THE PERIOD. AT THE SFC...RIDGING WILL SPREAD BACK OVER THE CWFA
FROM THE NW BY THE START OF THE PERIOD AND LINGER INTO EARLY NEXT
WEEK...GRADUALLY GETTING WEAKER. THE ECMWF STILL TRIES TO SPIN UP
SOME SORT OF SFC LOW TO OUR SOUTH BY THE END OF THE PERIOD...HOWEVER
THE GFS APPEARS LESS BULLISH ON LOW DEVELOPMENT NOW THAN IT HAS OVER
THE PAST COUPLE OF DAYS. ALSO OF NOTE...THE LONG RANGE MODEL
GUIDANCE IS NOW KEEPING THE PLUME OF DEEPER LYR MOISTURE FARTHER
SOUTH AND EAST COMPARED TO PREVIOUS GUIDANCE. THIS WILL ALLOW FOR
LOWER OVERALL POPS FOR MOST OF THE PERIOD. AS FOR THE SENSIBLE
FCST...WE CAN EXPECT MOSTLY DIURNAL CHANCES FOR SCT CONVECTION EACH
DAY/EVENING WITH THE BEST CHANCES OVER THE SE ZONES. TEMPS WILL
START OUT RIGHT AROUND NORMAL AND REMAIN NEAR NORMAL THROUGH THE
PERIOD.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AT KCLT...CONVECTION IS DEVELOPING QUICKLY EARLY THIS AFTN ACRS THE
AREA...WITH SEVERAL SLOW-MOVING SHRA JUST EAST OF THE TERMINAL AT
TIME OF 18Z TAF ISSUANCE. SO WILL START OUT WITH A VCSH AND TEMPO
FOR TS FROM 18-21Z. FROM THERE...THE HIGH-RES MODELS KEEP ISOLATED
TO SCATTERED CONVECTION LINGERING AROUND THE AREA WELL PAST SUNSET.
FOR SIMPLICITY...WILL KEEP OUT MENTION BEYOND 23Z.
OTHERWISE...TONIGHT WILL BE SIMILAR TO LAST NIGHT...WITH PLENTY OF
MID AND HIGH CLOUDS AND LIGHT SE WIND. GUIDANCE IS MIXED ON MVFR
STRATUS POTENTIAL. WILL MENTION SCT015 FOR NOW TO SHOW THE TREND.
ELSEWHERE...THE BLUE RIDGE HAS REALLY LIT UP ON RADAR OVER THE LAST
HOUR...WITH CONVECTION DRIFTING TO THE SOUTH. KGSP AND KGMU LOOK TO
HAVE THE BEST SHOT OF DIRECT HIT BY TSRA IN THE NEXT COUPLE HOURS.
ALL SITES WILL HAVE CONVECTION AROUND...SO WILL GO WITH VCTS AND
TEMPO FOR THE 18-21Z TIME FRAME. AS WITH KCLT ABOVE...GUIDANCE KEEPS
LINGERING CONVECTION BEYOND SUNSET. HOWEVER...OVERALL COVERAGE SHUD
CONTINUE TO DECREASE THRU THE NIGHT. PLENTY OF MOISTURE IN
PLACE...SO POTENTIAL FOR PATCHY FOG AND MVFR OR LOWER STRATUS.
CONFIDENCE ON EXACT IMPACTS IS LOW...BUT WILL GO WITH SIMILAR
TIMELINE AS WHAT OCCURRED LAST NIGHT.
KAVL AND KHKY MAY SEE VLIFR TO LIFR CONDITIONS THROUGH
MID MORNING. ELSEWHERE...MVFR CEILINGS MAY LINGER AT KGSP AND
DEVELOP AT KGMU DURING THE EARLY DAYLIGHT HOURS. THE AFTERNOON
APPROACH OF A WEAK MID LEVEL DISTURBANCE SHOULD YIELD A ROUND OF
SHRA/TSRA LATE THIS AFTERNOON AND EVENING. I WILL INCLUDE A PROB30
OR TEMPO IN EACH TAF...GENERALLY BETWEEN 20Z TO 24Z. MTN MVFR
CEILINGS MAY REDEVELOP LATE TONIGHT...ESPECIALLY OVER AREAS THAT SEE
RAIN THIS AFTERNOON AND EVENING.
OUTLOOK...A MID LEVEL RIDGE WILL REMAIN ACROSS THE WESTERN CAROLINAS
THROUGH MID WEEK. A LONGWAVE TROUGH WILL AMPLIFY ACROSS THE ATLANTIC
STATE LATE IN THE WEEK...WITH THE LIKELY PASSAGE OF A COLD FRONT ON
FRIDAY. THE POTENTIAL FOR CONVECTION WILL INCREASE EACH DAY THIS
WEEK.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 100% HIGH 100% HIGH 91% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 94%
KAVL HIGH 100% HIGH 100% HIGH 90% HIGH 87%
KHKY HIGH 100% HIGH 100% HIGH 94% HIGH 94%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1230 PM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM CDT TUE JUL 28 2015
UNSEASONABLY STRONG WAVE MOVING ALONG THE INTERNATIONAL BORDER EARLY
THIS MORNING...WITH STRONG WARM LAYER ALOFT AND LOW LEVEL JET ACROSS
THE CWA. MCS WITH ORIGINS IN WESTERN HIGH PLAINS CONTINUES TO WORK
EASTWARD ACROSS THE AREA EARLY THIS MORNING...FEATURING MAINLY SUB
SEVERE WINDS AND HEAVY RAINFALL TO THIS POINT. SUSTAINING UPPER
FORCING IS LIFTING NORTHWARD AWAY FROM THE AREA... AND SQUALL LINE
PUSHING TOWARD A BIT MORE STABLE CONDITIONS OVERALL. SEE NO REASON
THAT CONVECTIVE LINE WILL NOT CONTINUE TO MAINTAIN IN A GRADUALLY
WEAKENING STATE AS IT PUSHES EAST AT 40 MPH THROUGH THE EARLY
MORNING HOURS. LOW LEVEL SHEAR VECTORS SUGGEST MAY HAVE TO WATCH FOR
BREAKDOWN TO A FEW VORTICES...BUT HAVE BEEN UNABLE TO ESTABLISH
PERSISTENT ENOUGH UPDRAFTS ALONG THE LEADING EDGE TO THIS POINT...
AND PROSPECT FOR KEEPING FOCUSED UPDRAFTS WILL NOT GET ANY BETTER
WITH THE STATE OF THE AIRMASS. BOUNDARY WILL START TO LAY OUT A BIT
MORE THROUGH THE SOUTHERN CWA WITH TIME EARLY MORNING...AND HAVE
LINGERED SOME CHANCE LEVEL POPS INTO MID TO LATE MORNING ALONG THE
LOWER MISSOURI VALLEY. MAIN SURFACE BOUNDARY AND SHARPER DRYING BACK
WEST OF THE CWA AT 09Z...AND THIS MOISTURE DISCONTINUITY WILL
PROVIDE THE NEXT CHANCE FOR PRECIPITATION DURING THE AFTERNOON
HOURS. HOWEVER...WARM TEMPS ALOFT AND MODIFICATION OF THE AIRMASS BY
SQUALL LINE WILL PROVE DIFFICULT TO DESTABILIZATION. ALTHOUGH
SURFACE BOUNDARY HAS TRENDED JUST A TOUCH SLOWER THAN EARLIER RUN...
QUESTION WHETHER WILL BE ABLE TO REACH A RENEWED CONVECTIVE POINT
NEAR THE BOUNDARY AS IT WORKS TO CLEAR THE CWA DURING THE AFTERNOON.
ENOUGH OF A CAP INDICATED ON FAIRLY WARM RAP TO REALLY LIMIT ANY POP
MENTION TO LOWER CHANCE...AND SHOULD BE LARGELY CLEAR OF THE FAR
SOUTHEAST CWA BY 00-01Z. ANY STORMS THAT DO FORM WOULD HAVE A
CONDITIONAL SEVERE HAIL OR WIND THREAT ACROSS THE SOUTHEAST CWA
AFTER 19-20Z.
LIKELY GOING TO BE BIT SLOWER RELAXING HUMIDITY IN THE SOUTHERN AND
EASTERN AREAS WITH BOUNDARY STILL WELL BACK IN NW IA AND SW MN BY
18Z...BUT EVENTUAL PASSAGE OF FRONT WILL BRING NOTICEABLY LOWER
DEWPOINTS. STRONGER PUSH OF COOLING ALOFT WILL SETTLE IN TONIGHT AS
UPPER LOW MOVES NORTH OF THE AREA...WITH WESTERN WINDS DECOUPLING
SOME ACROSS THE SOUTH COMPARED TO NORTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 351 AM CDT TUE JUL 28 2015
WEDNESDAY AND THURSDAY BOTH LOOKING DRY AND WARM. WEDNESDAY ALSO
LOOKING A BIT WINDY...ESPECIALLY NORTH OF INTERSTATE 90 WHERE A FEW
GUSTS OF 30 TO 35 MPH ARE LIKELY. BY THURSDAY THE GRADIENT WILL
WEAKEN BUT THE LOW LEVEL AIR MASS LOOKS A BIT WARMER. HIGHS
WEDNESDAY IN THE LOWER TO MID 80S AND THURSDAY THE MID 80S TO LOWER
90S.
IN THE OUTER PERIODS(FRIDAY THROUGH MONDAY)...NORTHWEST FLOW ALOFT
IN PLACE THROUGH THE PERIOD WITH HIGHS MAINLY IN THE 80S AND LOWS
MAINLY IN THE 60S. SATURDAY STILL LOOKING LIKE THE DAY WHEN IT COULD
GET HOTTEST SO WILL KEEP SOME 90S ACROSS THE AREA. HUMIDITY WILL
ALSO BE PRETTY NORMAL FOR THIS TIME OF YEAR...MAYBE JUST A TOUCH
BELOW NORMAL...WITH DEW POINTS IN THE 60S. WILL MAINTAIN SOME SMALL
CHANCES FOR THUNDERSTORMS SATURDAY THROUGH MONDAY BUT AT THIS TIME
NOT CONFIDENT ENOUGH TO ADD ANYTHING OTHER THAN THAT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1226 PM CDT TUE JUL 28 2015
AREAS OF CEILINGS 1-3K FEET FROM BKX/FSD/SUX AND EAST WILL IMPROVE
TO VFR FROM THE WEST 18Z-23Z. ISOLATED TO SCATTERED TSRA IN
NORTHWEST IA EAST OF KSUX WILL MOVE EAST OF THE AREA BY 29/00Z.
OTHERWISE VFR THROUGH 29/18Z. A FEW SURFACE GUSTS FROM THE WEST OR
NORTHWEST MAY APPROACH 25 KNOTS OVER SOUTH DAKOTA THROUGH 29/00Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHAPMAN
LONG TERM...08
AVIATION...
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
648 AM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM CDT TUE JUL 28 2015
UNSEASONABLY STRONG WAVE MOVING ALONG THE INTERNATIONAL BORDER EARLY
THIS MORNING...WITH STRONG WARM LAYER ALOFT AND LOW LEVEL JET ACROSS
THE CWA. MCS WITH ORIGINS IN WESTERN HIGH PLAINS CONTINUES TO WORK
EASTWARD ACROSS THE AREA EARLY THIS MORNING...FEATURING MAINLY SUB
SEVERE WINDS AND HEAVY RAINFALL TO THIS POINT. SUSTAINING UPPER
FORCING IS LIFTING NORTHWARD AWAY FROM THE AREA... AND SQUALL LINE
PUSHING TOWARD A BIT MORE STABLE CONDITIONS OVERALL. SEE NO REASON
THAT CONVECTIVE LINE WILL NOT CONTINUE TO MAINTAIN IN A GRADUALLY
WEAKENING STATE AS IT PUSHES EAST AT 40 MPH THROUGH THE EARLY
MORNING HOURS. LOW LEVEL SHEAR VECTORS SUGGEST MAY HAVE TO WATCH FOR
BREAKDOWN TO A FEW VORTICES...BUT HAVE BEEN UNABLE TO ESTABLISH
PERSISTENT ENOUGH UPDRAFTS ALONG THE LEADING EDGE TO THIS POINT...
AND PROSPECT FOR KEEPING FOCUSED UPDRAFTS WILL NOT GET ANY BETTER
WITH THE STATE OF THE AIRMASS. BOUNDARY WILL START TO LAY OUT A BIT
MORE THROUGH THE SOUTHERN CWA WITH TIME EARLY MORNING...AND HAVE
LINGERED SOME CHANCE LEVEL POPS INTO MID TO LATE MORNING ALONG THE
LOWER MISSOURI VALLEY. MAIN SURFACE BOUNDARY AND SHARPER DRYING BACK
WEST OF THE CWA AT 09Z...AND THIS MOISTURE DISCONTINUITY WILL
PROVIDE THE NEXT CHANCE FOR PRECIPITATION DURING THE AFTERNOON
HOURS. HOWEVER...WARM TEMPS ALOFT AND MODIFICATION OF THE AIRMASS BY
SQUALL LINE WILL PROVE DIFFICULT TO DESTABILIZATION. ALTHOUGH
SURFACE BOUNDARY HAS TRENDED JUST A TOUCH SLOWER THAN EARLIER RUN...
QUESTION WHETHER WILL BE ABLE TO REACH A RENEWED CONVECTIVE POINT
NEAR THE BOUNDARY AS IT WORKS TO CLEAR THE CWA DURING THE AFTERNOON.
ENOUGH OF A CAP INDICATED ON FAIRLY WARM RAP TO REALLY LIMIT ANY POP
MENTION TO LOWER CHANCE...AND SHOULD BE LARGELY CLEAR OF THE FAR
SOUTHEAST CWA BY 00-01Z. ANY STORMS THAT DO FORM WOULD HAVE A
CONDITIONAL SEVERE HAIL OR WIND THREAT ACROSS THE SOUTHEAST CWA
AFTER 19-20Z.
LIKELY GOING TO BE BIT SLOWER RELAXING HUMIDITY IN THE SOUTHERN AND
EASTERN AREAS WITH BOUNDARY STILL WELL BACK IN NW IA AND SW MN BY
18Z...BUT EVENTUAL PASSAGE OF FRONT WILL BRING NOTICEABLY LOWER
DEWPOINTS. STRONGER PUSH OF COOLING ALOFT WILL SETTLE IN TONIGHT AS
UPPER LOW MOVES NORTH OF THE AREA...WITH WESTERN WINDS DECOUPLING
SOME ACROSS THE SOUTH COMPARED TO NORTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 351 AM CDT TUE JUL 28 2015
WEDNESDAY AND THURSDAY BOTH LOOKING DRY AND WARM. WEDNESDAY ALSO
LOOKING A BIT WINDY...ESPECIALLY NORTH OF INTERSTATE 90 WHERE A FEW
GUSTS OF 30 TO 35 MPH ARE LIKELY. BY THURSDAY THE GRADIENT WILL
WEAKEN BUT THE LOW LEVEL AIR MASS LOOKS A BIT WARMER. HIGHS
WEDNESDAY IN THE LOWER TO MID 80S AND THURSDAY THE MID 80S TO LOWER
90S.
IN THE OUTER PERIODS(FRIDAY THROUGH MONDAY)...NORTHWEST FLOW ALOFT
IN PLACE THROUGH THE PERIOD WITH HIGHS MAINLY IN THE 80S AND LOWS
MAINLY IN THE 60S. SATURDAY STILL LOOKING LIKE THE DAY WHEN IT COULD
GET HOTTEST SO WILL KEEP SOME 90S ACROSS THE AREA. HUMIDITY WILL
ALSO BE PRETTY NORMAL FOR THIS TIME OF YEAR...MAYBE JUST A TOUCH
BELOW NORMAL...WITH DEW POINTS IN THE 60S. WILL MAINTAIN SOME SMALL
CHANCES FOR THUNDERSTORMS SATURDAY THROUGH MONDAY BUT AT THIS TIME
NOT CONFIDENT ENOUGH TO ADD ANYTHING OTHER THAN THAT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 647 AM CDT TUE JUL 28 2015
MAIN ISSUES WITH AVIATION DEAL WITH DEPARTING CONVECTION IN
NORTHWEST IOWA...AND POTENTIAL FOR REDEVELOPMENT THIS AFTERNOON.
COULD YET SEE A COUPLE OF SHOWERS AROUND KSUX THROUGH THIS
MORNING. WAKE OF CONVECTIVE LINE BACK TO LOCATION OF THE
FRONTAL ZONE IN THE WESTERN CWA COULD SEE A BRIEF PERIOD OF MVFR
CEILINGS. OTHERWISE...WIND GUSTS OF 25 TO 30 KNOTS WILL BE
POSSIBLE AS MIXING INCREASES BEHIND BOUNDARY LATER THIS MORNING
AND AFTERNOON.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHAPMAN
LONG TERM...08
AVIATION...CHAPMAN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
351 AM CDT TUE JUL 28 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 351 AM CDT TUE JUL 28 2015
UNSEASONABLY STRONG WAVE MOVING ALONG THE INTERNATIONAL BORDER EARLY
THIS MORNING...WITH STRONG WARM LAYER ALOFT AND LOW LEVEL JET ACROSS
THE CWA. MCS WITH ORIGINS IN WESTERN HIGH PLAINS CONTINUES TO WORK
EASTWARD ACROSS THE AREA EARLY THIS MORNING...FEATURING MAINLY SUB
SEVERE WINDS AND HEAVY RAINFALL TO THIS POINT. SUSTAINING UPPER
FORCING IS LIFTING NORTHWARD AWAY FROM THE AREA... AND SQUALL LINE
PUSHING TOWARD A BIT MORE STABLE CONDITIONS OVERALL. SEE NO REASON
THAT CONVECTIVE LINE WILL NOT CONTINUE TO MAINTAIN IN A GRADUALLY
WEAKENING STATE AS IT PUSHES EAST AT 40 MPH THROUGH THE EARLY
MORNING HOURS. LOW LEVEL SHEAR VECTORS SUGGEST MAY HAVE TO WATCH FOR
BREAKDOWN TO A FEW VORTICES...BUT HAVE BEEN UNABLE TO ESTABLISH
PERSISTENT ENOUGH UPDRAFTS ALONG THE LEADING EDGE TO THIS POINT...
AND PROSPECT FOR KEEPING FOCUSED UPDRAFTS WILL NOT GET ANY BETTER
WITH THE STATE OF THE AIRMASS. BOUNDARY WILL START TO LAY OUT A BIT
MORE THROUGH THE SOUTHERN CWA WITH TIME EARLY MORNING...AND HAVE
LINGERED SOME CHANCE LEVEL POPS INTO MID TO LATE MORNING ALONG THE
LOWER MISSOURI VALLEY. MAIN SURFACE BOUNDARY AND SHARPER DRYING BACK
WEST OF THE CWA AT 09Z...AND THIS MOISTURE DISCONTINUITY WILL
PROVIDE THE NEXT CHANCE FOR PRECIPITATION DURING THE AFTERNOON
HOURS. HOWEVER...WARM TEMPS ALOFT AND MODIFICATION OF THE AIRMASS BY
SQUALL LINE WILL PROVE DIFFICULT TO DESTABILIZATION. ALTHOUGH
SURFACE BOUNDARY HAS TRENDED JUST A TOUCH SLOWER THAN EARLIER RUN...
QUESTION WHETHER WILL BE ABLE TO REACH A RENEWED CONVECTIVE POINT
NEAR THE BOUNDARY AS IT WORKS TO CLEAR THE CWA DURING THE AFTERNOON.
ENOUGH OF A CAP INDICATED ON FAIRLY WARM RAP TO REALLY LIMIT ANY POP
MENTION TO LOWER CHANCE...AND SHOULD BE LARGELY CLEAR OF THE FAR
SOUTHEAST CWA BY 00-01Z. ANY STORMS THAT DO FORM WOULD HAVE A
CONDITIONAL SEVERE HAIL OR WIND THREAT ACROSS THE SOUTHEAST CWA
AFTER 19-20Z.
LIKELY GOING TO BE BIT SLOWER RELAXING HUMIDITY IN THE SOUTHERN AND
EASTERN AREAS WITH BOUNDARY STILL WELL BACK IN NW IA AND SW MN BY
18Z...BUT EVENTUAL PASSAGE OF FRONT WILL BRING NOTICEABLY LOWER
DEWPOINTS. STRONGER PUSH OF COOLING ALOFT WILL SETTLE IN TONIGHT AS
UPPER LOW MOVES NORTH OF THE AREA...WITH WESTERN WINDS DECOUPLING
SOME ACROSS THE SOUTH COMPARED TO NORTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 351 AM CDT TUE JUL 28 2015
WEDNESDAY AND THURSDAY BOTH LOOKING DRY AND WARM. WEDNESDAY ALSO
LOOKING A BIT WINDY...ESPECIALLY NORTH OF INTERSTATE 90 WHERE A FEW
GUSTS OF 30 TO 35 MPH ARE LIKELY. BY THURSDAY THE GRADIENT WILL
WEAKEN BUT THE LOW LEVEL AIR MASS LOOKS A BIT WARMER. HIGHS
WEDNESDAY IN THE LOWER TO MID 80S AND THURSDAY THE MID 80S TO LOWER
90S.
IN THE OUTER PERIODS(FRIDAY THROUGH MONDAY)...NORTHWEST FLOW ALOFT
IN PLACE THROUGH THE PERIOD WITH HIGHS MAINLY IN THE 80S AND LOWS
MAINLY IN THE 60S. SATURDAY STILL LOOKING LIKE THE DAY WHEN IT COULD
GET HOTTEST SO WILL KEEP SOME 90S ACROSS THE AREA. HUMIDITY WILL
ALSO BE PRETTY NORMAL FOR THIS TIME OF YEAR...MAYBE JUST A TOUCH
BELOW NORMAL...WITH DEW POINTS IN THE 60S. WILL MAINTAIN SOME SMALL
CHANCES FOR THUNDERSTORMS SATURDAY THROUGH MONDAY BUT AT THIS TIME
NOT CONFIDENT ENOUGH TO ADD ANYTHING OTHER THAN THAT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 616 PM CDT MON JUL 27 2015
THUNDERSTORMS MAY DEVELOP ACROSS THE AREA OVERNIGHT...AFFECTING
KHON AROUND 05Z...THEN KFSD AND KSUX LATER AS THE SYSTEM PUSHES
TO THE EAST. WINDS WILL TRANSITION TO NORTHWESTERLY ON TUESDAY
MORNING BEHIND THE SYSTEM. SOME GUIDANCE SUGGESTING THAT THERE
COULD BE MVFR/IRF STRATUS DEVELOPMENT TOWARD TUESDAY MORNING.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHAPMAN
LONG TERM...08
AVIATION...JM
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1048 PM CDT WED JUL 29 2015
.UPDATE...
IR IMAGERY SHOWING WARMING TOPS OVER KY OVER THE LAST FEW HOURS.
ACTIVITY OVER OUR EASTERN SECTIONS CONTINUES TO WEAKEN. JUST
UPSTREAM...WEAK NW FLOW APPEARS TO BE IMPULSE FREE THROUGH THE
REMAINDER OF THE OVERNIGHT. THUS...WILL ADHERE TO THE HRRR DATA
AND REMOVE POPS FROM OUR NORTHWESTERN AREAS. WILL ALSO REDUCE POPS
SLIGHTLY ACROSS OUR EAST AND SOUTH.
CURRENT DEWPOINT SPREADS ARE RATHER LOW ACROSS OUR NORTH.
NUMERICAL DATA STILL NO INDICATING VSBYS FALLING TO 1SM OR LOWER.
LARGE AREA OF CLOUDINESS WILL SPREAD ACROSS THE AREA OVER THE NEXT
FEW HOURS AND LIKELY SLOW DOWN FOG DEVELOPMENT POTENTIAL. WILL GO
AHEAD AND INCREASE SKY GRIDS IN THE NEAR TERM. ALSO...A SLIGHT
DOWNWARD TWEAK OF TEMPS ACROSS THE FAR NORTH.
&&
.PREV DISCUSSION... /ISSUED 731 PM CDT WED JUL 29 2015/
DISCUSSION...
SYNOPTIC COMPARISONS OF 500 MB HEIGHTS REVEAL MORE OF AN ANTI
CYCLONIC FLOW OVER TN AS COMPARED TO 24 HRS AGO WHEN THE FLOW WAS
STRAIGHT. THIS ADDED EXERTIONS IS WORKING TO IMPEDE THE
CONTINUATION OF THE CONVECTION MOVING SOUTHWARD. SO...AS SFC TEMPS
COOL DOWN...THIS TREND SHOULD CONTINUE. HRRR IS IN SUPPORT OF THE
TREND.
ONLY CHANGE TO FCST WILL BE TO ADJUST POPS SLIGHTLY ACROSS THE
NORTHWEST. HEAT ADVISORY WAS ALLOWED TO EXPIRE AT 7PM.
PREV DISCUSSION... /ISSUED 724 PM CDT WED JUL 29 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
MONITORING A LINE OF SHWRS/TSTMS APPROACHING CKV AROUND 30/00Z...BUT
WEAKENING RAPIDLY. IT LOOKS LIKE AT WORST SOME BKN MVFR CB CEILINGS/VSBYS
CKV...BUT PROBABLY MORE LIKELY VFR CEILINGS...THRU 30/01Z. IF CONVECTION
HOLDS TOGETHER LONG ENOUGH...SOME VCTS MAY BE POSSIBLE AROUND BNA 30/01Z-
30/03Z. AS CONVECTION MOVES SEWD INTO MID STATE...POST BKN/OVC AC/CI
POSSIBLE THRU 30/06Z-30/07Z CKV/BNA. SFC FRONT EXPECTED TO MOVE TO
NEAR CKV BY 30/06Z AND TO PUSH E OF CSV 30/12Z-30/14Z. AS SFC FRONT
APPROACHES CSV...MVFR CEILING/FOG FORMATION EXPECTED. MVFR FOG CKV/BNA
30/08Z-30/14Z. BUILDING RIDGING INFLUENCES SFC/ALOFT SHOULD PROVIDE
VFR/SKC CONDITIONS ALL TAF SITES 30/15Z-30/24Z.
PREV DISCUSSION.../ISSUED 329 PM CDT WED JUL 29 2015/
DISCUSSION...
HOT AND HUMID CONDITIONS CONTINUE ACROSS MIDDLE TENNESSEE THIS
AFTERNOON AS THE SHOWERS AND THUNDERSTORMS THAT MOVED THROUGH THE
AREA EARLIER THIS MORNING LEFT QUITE THE SOUPY AIRMASS IN PLACE.
FOR THIS EVENING AND TONIGHT...STILL THINK A FEW ISOLATED SHOWERS
AND THUNDERSTORMS MAY DEVELOP...BUT WILL SIDE WITH THE HRRR AS MUCH
OF THE AREA WILL REMAIN DRY. A COLD FRONT WILL PUSH ACROSS MIDDLE
TENNESSEE OVERNIGHT BRINGING MUCH DRIER AIR...A VERY NICE CHANGE
IN TIME FOR THE WEEKEND.
THURSDAY THROUGH TUESDAY...A QUIET WEATHER PATTERN CAN BE
EXPECTED...ESPECIALLY FOR THE BEGINNING OF AUGUST...AS HIGH
PRESSURE BUILDS OVER THE REGION. CONDITIONS WILL NOT BE QUITE AS
HUMID ALTHOUGH HIGHS WILL STILL REACH THE LOWER 90S IN MOST
LOCATIONS. BIGGEST DIFFERENCE WILL BE FELT WITH LOW TEMPERATURES
WITH MID TO UPPER 60S EXPECTED INSTEAD OF THE LOWER TO MID 70S.
TEMPERATURES WILL SLOWLY BEGIN TO INCREASE AFTER THE
WEEKEND...ALONG WITH HUMIDITY VALUES TOO.
BY THE MIDDLE OF NEXT WEEK...UPPER LEVEL PATTERN WILL AGAIN SHIFT
TO NORTHWEST FLOW AS THE SURFACE HIGH LOSES ITS STRONGHOLD. AS A
RESULT...THUNDERSTORM CHANCES WILL INCREASE TUESDAY NIGHT AND
LIKELY REMAIN IN THE FORECAST THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 74 90 66 90 / 20 10 0 0
CLARKSVILLE 71 88 65 89 / 10 0 0 0
CROSSVILLE 72 85 64 84 / 30 20 0 0
COLUMBIA 74 90 66 90 / 20 20 0 0
LAWRENCEBURG 74 90 66 89 / 20 20 0 0
WAVERLY 72 89 67 89 / 10 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
731 PM CDT WED JUL 29 2015
.DISCUSSION...
SYNOPTIC COMPARISONS OF 500 MB HEIGHTS REVEAL MORE OF AN ANTI
CYCLONIC FLOW OVER TN AS COMPARED TO 24 HRS AGO WHEN THE FLOW WAS
STRAIGHT. THIS ADDED EXERTIONS IS WORKING TO IMPEDE THE
CONTINUATION OF THE CONVECTION MOVING SOUTHWARD. SO...AS SFC TEMPS
COOL DOWN...THIS TREND SHOULD CONTINUE. HRRR IS IN SUPPORT OF THE
TREND.
ONLY CHANGE TO FCST WILL BE TO ADJUST POPS SLIGHTLY ACROSS THE
NORTHWEST. HEAT ADVISORY WAS ALLOWED TO EXPIRE AT 7PM.
&&
.PREV DISCUSSION... /ISSUED 724 PM CDT WED JUL 29 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
MONITORING A LINE OF SHWRS/TSTMS APPROACHING CKV AROUND 30/00Z...BUT
WEAKENING RAPIDLY. IT LOOKS LIKE AT WORST SOME BKN MVFR CB CEILINGS/VSBYS
CKV...BUT PROBABLY MORE LIKELY VFR CEILINGS...THRU 30/01Z. IF CONVECTION
HOLDS TOGETHER LONG ENOUGH...SOME VCTS MAY BE POSSIBLE AROUND BNA 30/01Z-
30/03Z. AS CONVECTION MOVES SEWD INTO MID STATE...POST BKN/OVC AC/CI
POSSIBLE THRU 30/06Z-30/07Z CKV/BNA. SFC FRONT EXPECTED TO MOVE TO
NEAR CKV BY 30/06Z AND TO PUSH E OF CSV 30/12Z-30/14Z. AS SFC FRONT
APPROACHES CSV...MVFR CEILING/FOG FORMATION EXPECTED. MVFR FOG CKV/BNA
30/08Z-30/14Z. BUILDING RIDGING INFLUENCES SFC/ALOFT SHOULD PROVIDE
VFR/SKC CONDITIONS ALL TAF SITES 30/15Z-30/24Z.
PREV DISCUSSION.../ISSUED 329 PM CDT WED JUL 29 2015/
DISCUSSION...
HOT AND HUMID CONDITIONS CONTINUE ACROSS MIDDLE TENNESSEE THIS
AFTERNOON AS THE SHOWERS AND THUNDERSTORMS THAT MOVED THROUGH THE
AREA EARLIER THIS MORNING LEFT QUITE THE SOUPY AIRMASS IN PLACE.
FOR THIS EVENING AND TONIGHT...STILL THINK A FEW ISOLATED SHOWERS
AND THUNDERSTORMS MAY DEVELOP...BUT WILL SIDE WITH THE HRRR AS MUCH
OF THE AREA WILL REMAIN DRY. A COLD FRONT WILL PUSH ACROSS MIDDLE
TENNESSEE OVERNIGHT BRINGING MUCH DRIER AIR...A VERY NICE CHANGE
IN TIME FOR THE WEEKEND.
THURSDAY THROUGH TUESDAY...A QUIET WEATHER PATTERN CAN BE
EXPECTED...ESPECIALLY FOR THE BEGINNING OF AUGUST...AS HIGH
PRESSURE BUILDS OVER THE REGION. CONDITIONS WILL NOT BE QUITE AS
HUMID ALTHOUGH HIGHS WILL STILL REACH THE LOWER 90S IN MOST
LOCATIONS. BIGGEST DIFFERENCE WILL BE FELT WITH LOW TEMPERATURES
WITH MID TO UPPER 60S EXPECTED INSTEAD OF THE LOWER TO MID 70S.
TEMPERATURES WILL SLOWLY BEGIN TO INCREASE AFTER THE
WEEKEND...ALONG WITH HUMIDITY VALUES TOO.
BY THE MIDDLE OF NEXT WEEK...UPPER LEVEL PATTERN WILL AGAIN SHIFT
TO NORTHWEST FLOW AS THE SURFACE HIGH LOSES ITS STRONGHOLD. AS A
RESULT...THUNDERSTORM CHANCES WILL INCREASE TUESDAY NIGHT AND
LIKELY REMAIN IN THE FORECAST THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 75 90 66 90 / 30 10 0 0
CLARKSVILLE 71 88 65 89 / 40 0 0 0
CROSSVILLE 72 85 64 84 / 30 20 0 0
COLUMBIA 75 90 66 90 / 20 20 0 0
LAWRENCEBURG 74 90 66 89 / 20 20 0 0
WAVERLY 73 89 67 89 / 30 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
724 PM CDT WED JUL 29 2015
.UPDATE...FOR 00Z AVIATION DISCUSSION.
&&
.AVIATION UPDATE...00Z AVIATION DISCUSSION.
MONITORING A LINE OF SHWRS/TSTMS APPROACHING CKV AROUND 30/00Z...BUT
WEAKENING RAPIDLY. IT LOOKS LIKE AT WORST SOME BKN MVFR CB CEILINGS/VSBYS
CKV...BUT PROBABLY MORE LIKELY VFR CEILINGS...THRU 30/01Z. IF CONVECTION
HOLDS TOGETHER LONG ENOUGH...SOME VCTS MAY BE POSSIBLE AROUND BNA 30/01Z-
30/03Z. AS CONVECTION MOVES SEWD INTO MID STATE...POST BKN/OVC AC/CI
POSSIBLE THRU 30/06Z-30/07Z CKV/BNA. SFC FRONT EXPECTED TO MOVE TO
NEAR CKV BY 30/06Z AND TO PUSH E OF CSV 30/12Z-30/14Z. AS SFC FRONT
APPROACHES CSV...MVFR CEILING/FOG FORMATION EXPECTED. MVFR FOG CKV/BNA
30/08Z-30/14Z. BUILDING RIDGING INFLUENCES SFC/ALOFT SHOULD PROVIDE
VFR/SKC CONDITIONS ALL TAF SITES 30/15Z-30/24Z.
&&
.PREV DISCUSSION.../ISSUED 329 PM CDT WED JUL 29 2015/
DISCUSSION...
HOT AND HUMID CONDITIONS CONTINUE ACROSS MIDDLE TENNESSEE THIS
AFTERNOON AS THE SHOWERS AND THUNDERSTORMS THAT MOVED THROUGH THE
AREA EARLIER THIS MORNING LEFT QUITE THE SOUPY AIRMASS IN PLACE.
FOR THIS EVENING AND TONIGHT...STILL THINK A FEW ISOLATED SHOWERS
AND THUNDERSTORMS MAY DEVELOP...BUT WILL SIDE WITH THE HRRR AS MUCH
OF THE AREA WILL REMAIN DRY. A COLD FRONT WILL PUSH ACROSS MIDDLE
TENNESSEE OVERNIGHT BRINGING MUCH DRIER AIR...A VERY NICE CHANGE
IN TIME FOR THE WEEKEND.
THURSDAY THROUGH TUESDAY...A QUIET WEATHER PATTERN CAN BE
EXPECTED...ESPECIALLY FOR THE BEGINNING OF AUGUST...AS HIGH
PRESSURE BUILDS OVER THE REGION. CONDITIONS WILL NOT BE QUITE AS
HUMID ALTHOUGH HIGHS WILL STILL REACH THE LOWER 90S IN MOST
LOCATIONS. BIGGEST DIFFERENCE WILL BE FELT WITH LOW TEMPERATURES
WITH MID TO UPPER 60S EXPECTED INSTEAD OF THE LOWER TO MID 70S.
TEMPERATURES WILL SLOWLY BEGIN TO INCREASE AFTER THE
WEEKEND...ALONG WITH HUMIDITY VALUES TOO.
BY THE MIDDLE OF NEXT WEEK...UPPER LEVEL PATTERN WILL AGAIN SHIFT
TO NORTHWEST FLOW AS THE SURFACE HIGH LOSES ITS STRONGHOLD. AS A
RESULT...THUNDERSTORM CHANCES WILL INCREASE TUESDAY NIGHT AND
LIKELY REMAIN IN THE FORECAST THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 75 90 66 90 / 20 10 0 0
CLARKSVILLE 71 88 65 89 / 20 0 0 0
CROSSVILLE 72 85 64 84 / 30 20 0 0
COLUMBIA 75 90 66 90 / 20 20 0 0
LAWRENCEBURG 74 90 66 89 / 20 20 0 0
WAVERLY 73 89 67 89 / 20 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
509 PM CDT TUE JUL 28 2015
.UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS TO ADD A LATE AFTERNOON
ZONE GROUPING TO THE ZONE FORECAST PRODUCT TO EMPHASIZE SCT SHWR/TSTM
CONVECTION ACROSS MID STATE. ALSO ADJUSTED HRLY TEMP...DEWPOINT...
WIND DIRECTION/SPEED...AND SKY CONDITION GRIDS.
&&
.PREV DISCUSSION.../ISSUED 236 PM CDT TUE JUL 28 2015/
DISCUSSION...
UPPER RIDGE HAS A STRONGHOLD ON MUCH OF THE AREA WITH HIGH HEAT
INDICIES PROMPTING A HEAT ADVISORY FOR A GOOD PART OF THE MID
STATE UNTIL 7 PM CDT THIS EVENING. CONVECTION HAS FIRED IN THE
AFTERNOON HEAT MAINLY ACROSS EASTERN AREAS AND ALONG THE PLATEAU
WITH MORE CONVECTION DROPPING SOUTH BOUND FROM KENTUCKY. LOOKS
LIKE A VORTICITY MAX (SHORT WAVE) WORKING DOWN FRONT SIDE OF
UPPER RIDGE. VORT MAX CURRENTLY SHOWING UP IN LATEST RUC13 RUN
NOSING JUST SOUTH OF OHIO RIVER SOUTH OF LOUISVILLE...HEADED THIS
WAY. SHORT WAVE SHOULD ENHANCE CONVECTION OVER SOUTH CENTRAL
KENTUCKY THAT WILL WORK DOWN INTO MIDDLE TENNESSEE REMAINDER OF
THE AFTERNOON AND INTO THE EVENING. MODELS KEEP SOME CONVECTION
AROUND AFTER MIDNIGHT WITH WESTERN AREAS OF THE MID STATE FAVORED.
ANOTHER HOT DAY WEDNESDAY WITH AN INCREASED CHANCE OF RAIN AS FRONT
APPROACHES FROM THE NORTHWEST. SHOWER AND THUNDERSTORMS WILL RAMP
UP WEDNESDAY EVENING AND OVERNIGHT AS FRONT WORKS INTO THE MID
STATE. SHOWER AND THUNDERSTORM CHANCES CONTINUE SOUTHEAST HALF ON
THURSDAY BUT DRY THURSDAY NIGHT AND THROUGH THE UPCOMING WEEKEND.
UPPER RIDGE THAT HAS KEPT TEMPS ABOVE NORMAL AND HEAT INDICIES
AROUND TRIPLE DIGITS WILL FINALLY RETROGRADE ALLOWING UPPER TROUGH
TO DOMINATE FRIDAY THROUGH THE WEEKEND. NEXT CHANCE FOR RAIN LOOKS
TO BE ABOUT THE MIDDLE OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 76 94 75 90 / 40 30 40 30
CLARKSVILLE 75 94 72 87 / 30 30 40 10
CROSSVILLE 71 87 72 84 / 40 30 40 50
COLUMBIA 75 93 74 91 / 30 30 40 40
LAWRENCEBURG 75 90 73 90 / 30 30 40 50
WAVERLY 75 95 73 88 / 30 30 40 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TNZ005>008-023>028-
056>062-075-093>095.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
236 PM CDT TUE JUL 28 2015
.DISCUSSION...
UPPER RIDGE HAS A STRONGHOLD ON MUCH OF THE AREA WITH HIGH HEAT
INDICIES PROMPTING A HEAT ADVISORY FOR A GOOD PART OF THE MID
STATE UNTIL 7 PM CDT THIS EVENING. CONVECTION HAS FIRED IN THE
AFTERNOON HEAT MAINLY ACROSS EASTERN AREAS AND ALONG THE PLATEAU
WITH MORE CONVECTION DROPPING SOUTH BOUND FROM KENTUCKY. LOOKS
LIKE A VORTICITY MAX (SHORT WAVE) WORKING DOWN FRONT SIDE OF
UPPER RIDGE. VORT MAX CURRENTLY SHOWING UP IN LASTEST RUC13 RUN
NOSING JUST SOUTH OF OHIO RIVER SOUTH OF LOUISVILLE...HEADED THIS
WAY. SHORT WAVE SHOULD ENHANCE CONVECTION OVER SOUTH CENTRAL
KENTUCKY THAT WILL WORK DOWN INTO MIDDLE TENNESSEE REMAINDER OF
THE AFTERNOON AND INTO THE EVENING. MODELS KEEP SOME CONVECTION
AROUND AFTER MIDNIGHT WITH WESTERN AREAS OF THE MID STATE FAVORED.
ANOTHER HOT DAY WEDNESDAY WITH AN INCREASED CHANCE OF RAIN AS FRONT
APPROACHES FROM THE NORTHWEST. SHOWER AND THUNDERSTORMS WILL RAMP
UP WEDNESDAY EVENING AND OVERNIGHT AS FRONT WORKS INTO THE MID
STATE. SHOWER AND THUNDERSTORM CHANCES CONTINUE SOUTHEAST HALF ON
THURSDAY BUT DRY THURSDAY NIGHT AND THROUGH THE UPCOMING WEEKEND.
UPPER RIDGE THAT HAS KEPT TEMPS ABOVE NORMAL AND HEAT INDICIES
AROUND TRIPLE DIGITS WILL FINALLY RETROGRADE ALLOWING UPPER TROUGH
TO DOMINATE FRIDAY THROUGH THE WEEKEND. NEXT CHANCE FOR RAIN LOOKS
TO BE ABOUT THE MIDDLE OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 76 94 75 90 / 40 30 40 30
CLARKSVILLE 75 94 72 87 / 30 30 40 10
CROSSVILLE 71 87 72 84 / 40 30 40 50
COLUMBIA 75 93 74 91 / 20 30 40 40
LAWRENCEBURG 75 90 73 90 / 30 30 40 50
WAVERLY 75 95 73 88 / 30 30 40 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TNZ005>008-023>028-
056>062-075-093>095.
&&
$$
BOYD
01
AREA FORECAST DISCUSSION...UPDATED
NWS MIDLAND/ODESSA TX
926 PM CDT WED JUL 29 2015
.UPDATE...
Reduced rain chances across western zones including mountains.
Holding on to slight chances over mountains and Permian Basin.
&&
.DISCUSSION...
Showers winding down across area with loss of daytime heating. A
few stubborn showers holding on in Permian Basin aided by
converging outflow boundaries. Should see most shower activity
dissipate by midnight.
&&
.PREV DISCUSSION... /ISSUED 542 PM CDT WED JUL 29 2015/
DISCUSSION...
See 00Z Aviation Discussion below.
AVIATION...
Area radars and short-term models show another night of convection
on tap, mainly SE NM, although many boundaries abound elsewhere.
Regardless, VFR conditions will prevail next 24 hours in return
flow under persistent ridging aloft. Forecast soundings develop a
widespread cu field by late Thursday morning, w/initial bases
4.5-6 kft agl.
PREV DISCUSSION... /ISSUED 332 PM CDT WED JUL 29 2015/
UPDATE...
Updated forecast for increased chance of thunderstorms over the
northern Permian Basin, southeast New Mexico and mountain areas.
DISCUSSION...
By mid-afternoon, showers and thunderstorms were developing along
a surface boundary entering the northern Permian Basin in an area
characterized by CAPE values ranging from 500 to 1000. Continued
development along this boundary as well as any additional outflow
boundaries that might develop is possible through early evening as
the atmosphere across the region is uncapped. Though instability
is less over the Permian Basin, will need to watch boundaries for
possible foci of development. Thunderstorms will begin to
decrease this evening with a loss of heating. Though shear is
insufficient for organized thunderstorm activity, DCAPE values are
significant, in excess of 1000. Sub-cloud evaporation will be
capable of producing strong and possibly damaging downbursts.
PREV DISCUSSION... /ISSUED 224 PM CDT WED JUL 29 2015/
DISCUSSION...As of 2:15 PM CDT Wednesday...Hot and muggy weather
continues with convection starting in the usual places...the
Davis/Guadalupe Mtns and the adjacent Plains. Convection is also
forming a little further east in Western Lea and Eddy Counties
along the thetae ridge per the HRRR and RAP13 high res models.
The persistent subtropical ridge centered over the Arklatex area
will shift west over the Central Plains as a trough deepens in the
eastern US. This might actually result in no convection in the
CWA Thursday thru Friday due to increased subsidence from the
ridge center moving overhead. Temps might not be as hot as the
previous week...but will remain above normal.
Medium range models are hinting at the possibility of convection
in the CWA over the weekend as the ridge continues to shift west
to over the four corners area. This will bring a NW flow aloft
possibly bringing convection into the area out of Northern New
Mexico.
As a trough in the EastPac moves into the Pacific NW early next
week the ridge will flatten and elongate bringing a return to
drier weather...with triple digits possible once again in the
Plains by mid week.
Strobin
&&
.PRELIMINARY POINT TEMPS/POPS...
BIG SPRING TX 74 97 73 96 / 10 10 0 10
CARLSBAD NM 70 97 69 96 / 20 10 0 0
DRYDEN TX 75 100 74 99 / 10 0 0 0
FORT STOCKTON TX 72 98 73 97 / 10 0 0 0
GUADALUPE PASS TX 68 89 68 88 / 20 10 10 10
HOBBS NM 70 95 70 93 / 10 10 10 10
MARFA TX 59 90 57 88 / 10 10 0 10
MIDLAND INTL AIRPORT TX 73 98 72 97 / 20 0 0 10
ODESSA TX 73 98 74 97 / 20 0 0 0
WINK TX 75 103 73 101 / 20 0 0 0
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
99/05
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1125 PM CDT Mon Jul 27 2015
.AVIATION...
/06Z TAFS/
Skies were mostly clear across the region and the winds have
mostly diminished. Could see a few scattered clouds at KJCT and
KSOA by 12Z. Tomorrow looks like a carbon copy of today, VFR and
southeast winds of 10 to 15 kts.
&&
.PREV DISCUSSION... /ISSUED 626 PM CDT Mon Jul 27 2015/
AVIATION...
/00Z TAFS/
High based cumulus will likely dissipate shortly around sunset
along with the summer breeze. Winds will vary in both direction and
speeds. However, the wind speeds should remain below 12 knots most
of the time. VFR to continue through 00Z Tuesday as an upper level high
remains in control of the region.
PREV DISCUSSION... /ISSUED 322 PM CDT Mon Jul 27 2015/
SHORT TERM...
(Tonight and Tuesday)
A cumulus field was developing east of a Sweetwater to Junction
line early this afternoon. The HRRR model develops isolated
showers and thunderstorms in the Big Country this afternoon/early
evening, while the Texas Tech WRF model has a few storms along the
I-10 corridor. Expanded coverage of isolated showers and
thunderstorms to include the Big Country counties this
afternoon/evening, with storms ending by sunset.
Models have a slight cooling by a degree or two Tuesday as the
center of upper high pressure moves north into Oklahoma.
Unfortunately this still means highs in the upper 90s to around
102, with the warmest readings in the Concho Valley.
04
LONG TERM...
(Tuesday night through Monday)
Hot and dry conditions are anticipated across West Central Texas
for much of the work-week as the subtropical ridge remains
entrenched over the southern plains. Temperatures are expected to
moderate slightly through Thursday as mid-level temperatures
gradually drop by 1-2C. This will put max temperatures at or below
100 degrees by midweek, with overnight lows remaining in the mid
70s. We should see an afternoon cu field each afternoon, but large
scale subsidence should preclude convective initiation. Heat
indices are expected to remain below 105 degrees, precluding the
need for a Heat Advisory.
The mid/upper-level anticyclone is progged to build toward the
west late this week, eventually centering over the Four Corners
area this weekend. As the ridge builds west, the flow aloft will
become northwesterly, opening the door for weak shortwave troughs
to move across the region. A slug of enhanced moisture will move
west across the Lone Star state late in the week and is forecast
to increase precipitable water values to near 1.7" over the
southeast portion of the CWA on Friday. With temperatures
approaching 100 degrees, the cap is expected to break, allowing a
few diurnal showers and thunderstorms to develop. Slight chance
PoPs were added for areas east of a line from Sonora, to Ballinger
to Throckmorton.
This moisture will hang around through Saturday, where slight
chance PoPs continue areawide. The ridge builds back east on
Sunday, with hot and dry weather returning to the CWA. Expect
temperatures near or back above 100 degrees across much of the
area by Sunday.
Johnson
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 76 98 76 98 76 / 10 5 0 5 0
San Angelo 75 102 76 101 75 / 10 5 0 5 0
Junction 74 100 75 98 73 / 10 5 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
26/99/99
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
953 PM EDT WED JUL 29 2015
.SYNOPSIS...
UPPER RIDGE WILL STAY CENTERED OVER THE SOUTHERN U.S. TONIGHT. A
FRONT WILL SLIDE ACROSS OUR REGION THURSDAY...STALLING ALONG THE
SOUTHEAST COAST FRIDAY INTO SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 950 PM EDT WEDNESDAY...
LOCAL WRF AND SOME RUNS OF HRRR HAVE SOME PRE-FRONTAL SHOWERS AND
THUNDERSTORMS MOVING INTO THE MOUNTAINS AROUND AFTER
MIDNIGHT...AROUND 05/06Z. HAVE TRIMMED BACK PROBABILITY OF
PRECIPITATION BASED ON THE LATEST RADAR TRENDS THEN HAVE
PROBABILITY INCREASING IN THE WEST LATE TONIGHT. LITTLE TO NO
CHANGE NEEDED FRO MINIMUM TEMPERATURES.
A COLD FRONT APPROACHES TONIGHT FROM THE WEST AND SHOULD REACH
THE OHIO RIVER BY 8 AM THURSDAY MORNING. LOW LEVEL MOISTURE AND
LIGHT WINDS WILL RESULT IN AREAS OF FOG OVERNIGHT. LOWS WILL RANGE
FROM THE UPPER 60S TO LOWER 70S FOR MOST OF THE REGION.
A COLD FRONT WILL TRAVEL EAST ACROSS THE REGION THURSDAY INTO
THURSDAY EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP AHEAD AND ALONG THE FRONT. THE SWODY2 CONVECTIVE OUTLOOK
KEEPS OUR CWA IN THE GENERAL THUNDERSTORMS AND SPLITS THE MARGINAL
POTENTIAL TO OUR NORTH AND SOUTH. HIGH TEMPERATURES WILL CLIMB INTO
THE MID 70S IN THE NORTHWEST MOUNTAINS TO THE LOWER 90S IN THE
PIEDMONT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 230 PM EDT WEDNESDAY...
COLD FRONT WILL BE HEADING TO THE COAST THURSDAY EVENING FOLLOWED BY
COOLER HIGH PRESSURE THAT WILL BUILD IN FROM THE WEST THURSDAY NIGHT
INTO FRIDAY. LIKELY TO SEE A BAND OF POST FRONTAL TYPE SHALLOW
CONVECTION OVER THE PIEDMONT DURING THE EARLY EVENING GIVEN MODEST
FORECAST INSTABILITY BEFORE THE AXIS OF DEEP MOISTURE PUSHES TO THE
EAST AND OUT OF THE REGION BY MIDNIGHT. THUS LEAVING IN SOME LOW CHANCE
POPS EAST OF THE BLUE RIDGE BEFORE SEEING CLEARING AND COOLER WEATHER
ALL SECTIONS LATER THURSDAY NIGHT.
WITH 85H TEMPS FALLING TO BETWEEN +14-16C EXPECT QUITE A FEW LOW TEMPS
IN THE 50S TO AROUND 60 ACROSS THE VALLEYS WITH DRIER LOW/MID 60S OUT
EAST. A MAINLY SUNNY AND MUCH LESS HUMID FRIDAY LOOKS ON TAP UNDER GOOD
SUBSIDENCE AND LOW LEVEL NW FLOW. HOWEVER HEATING OF THE DRY AIR WILL
PUSH TEMPS BACK INTO THE LOW/MID 80S MOUNTAINS...AND STILL CLOSE TO 90
SE BUT WITH MUCH LESS HUMIDITY.
AFTER ANOTHER RATHER COOL MORNING SATURDAY...SHOULD SEE TEMPS REBOUND
SLIGHTLY SATURDAY AFTERNOON AS THICKNESS VALUES RISE A BIT AHEAD OF A
SECONDARY TYPE DRY BOUNDARY THAT WILL CROSS THE REGION LATE WITH
ANOTHER QUICK SHOT OF COOL ADVECTION INTO SATURDAY NIGHT. CANT TOTALLY
RULE OUT AN UPSLOPE SPRINKLE OVER NW SECTIONS LATE SATURDAY WHEN LOW
LEVEL NW FLOW WILL BE STRONGEST OTRW TOO DRY FOR MUCH MORE THAN SOME
CLOUDS AT BEST. THIS TO BE FOLLOWED BY YET ANOTHER COMFORTABLE
OVERNIGHT WITH TEMPS FALLING INTO THE 50S TO LOW 60S MOUNTAINS AND
LOW/MID 60S AGAIN OUT EAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 1230 PM EDT WEDNESDAY...
PREDOMINATE UPPER TROFFINESS ACROSS THE MID ATLANTIC WILL KEEP NW FLOW
ALOFT IN PLACE FROM THE WEEKEND THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. THIS SHOULD INITIALLY KEEP OVERALL DRY WEATHER IN PLACE WITH
SURFACE HIGH PRESSURE BUILDING ACROSS THE REGION FROM THE NW SUNDAY-
MONDAY...AND TO THE SOUTH AHEAD OF A REINFORCING COLD FRONT BY
WEDNESDAY. ONLY EXCEPTION TO THIS COULD BE WITH MOISTURE BEING LIFTED
BACK INTO THE SE EARLY NEXT WEEK WITH LOW PRESSURE DEVELOPING ALONG THE
RESIDUAL FRONT NEAR THE COAST. HOWEVER THE EARLIER ECMWF AND CMC ABOUT
THE ONLY SOLUTIONS THAT STILL HINT AT THIS SO BASICALLY LEAVING OUT
MOST POPS OUTSIDE OF SOMETHING ISOLATED SE SECTIONS ON MONDAY.
COLUMN WILL GRADUALLY MOISTEN ENOUGH BY MIDWEEK TO POSSIBLY SUPPORT A
BIT MORE CONVECTION AS WEAK SHORTWAVES ALOFT TRAVERSE THE NW FLOW ON
TUESDAY AHEAD OF A STRONGER UPPER LOW AND COLD FRONT TO THE NORTH
WEDNESDAY. GUIDANCE REMAINS A BIT HESITANT TO PRODUCE MUCH IN THE WAY
OF PRECIP GIVEN MAIN LIFT TO THE NORTH BUT APPEARS ENOUGH FOCUS WITH
HEATING TO SUPPORT SOME LOW POPS TUESDAY AFTERNOON. BETTER CHANCES MAY
COME WEDNESDAY AS THE FRONT SAGS TOWARD THE AREA FROM THE NORTH AND
DEWPOINTS RISE BUT EVEN THEN SUPPORT THIS FAR SOUTH LACKING SO CHANCE
POPS IN ORDER. OTRW MAINLY A PERSISTENCE FORECAST WITH HIGHS 80S TO
AROUND 90 SE AND 60S OVERNIGHT EXCEPT SOME COOLER 50S VALLEYS EARLY IN
THE WEEK AS DEWPOINTS/HUMIDITY REMAIN LOW.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
AS OF 800 PM EDT WEDNESDAY...
AREA RADARS SHOWED ISOLATED SHOWERS AND THUNDERSTORMS OVER WEST
VIRGINIA...SOUTHWEST VIRGINIA AND NORTHWEST NORTH CAROLINA THIS
EVENING. SOME OF THE RAIN WAS CLOSE TO THE LOCAL AIRPORTS...BUT
NOT CLOSE ENOUGH TO INCLUDE IN THE TAFS AT THIS TIME.
AIR MASS REMAINS VERY MOIST AT LOW LEVELS TONIGHT. HIGH CONFIDENCE
FOR THE DEVELOPMENT OF MVFR FOG BY MIDNIGHT. COVERAGE OF SHOWERS
AND THUNDERSTORMS WILL REMAIN ISOLATED UNTIL THE FRONT APPROACHES
THE APPALACHIANS AFTER 10Z/6AM. IFR TO LIFR FOG IS ALSO EXPECTED
AT KBCB AND KLWB.
MODELS...INCLUDING DIFFERENT VERSIONS OF THE HRRR SUGGESTS SOME PREFRONTAL
SHOWERS AND THUNDERSTORMS MAY MOVE INTO THE MOUNTAINS AFTER
MIDNIGHT...BUT THAT THERE WILL BE LITTLE TO PRECIPITATION ALONG
THE ACTUAL FRONT. THUNDERSTORMS MAY DEVELOP ALONG THE BOUNDARY
EAST OF THE BLUE RIDGE SO HAVE INCLUDED VC IN THE KLYH AND KDAN
TAFS FOR THURSDAY AFTERNOON.
A MUCH DRIER AIR MASS COMES INTO THE REGION BEHIND THE FRONT BY
THURSDAY NIGHT.
EXTENDED AVIATION FORECAST...
BEHIND THE FRONT THE WEATHER WILL BE DRY AND VFR FRIDAY THROUGH
SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...KK
SHORT TERM...JH
LONG TERM...JH
AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
812 PM EDT WED JUL 29 2015
.SYNOPSIS...
UPPER RIDGE WILL STAY CENTERED OVER THE SOUTHERN U.S. TONIGHT. A
FRONT WILL SLIDE ACROSS OUR REGION THURSDAY...STALLING ALONG THE
SOUTHEAST COAST FRIDAY INTO SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 333 PM EDT WEDNESDAY...
ISOLATED TO SCATTERED CONVECTION EXPECTED THIS AFTERNOON INTO
TONIGHT WITH THE COMBINATION OF DIFFERENTIAL HEATING...LEFTOVER
BOUNDARIES AND WEAK UPPER LEVEL DISTURBANCES. THE WIND FLOW REMAINS
WEAK AT 5-15 KTS...WITH PWATS AROUND 1.5 INCHES SO A FEW STORMS
COULD HAVE THE POTENTIAL FOR LOCALLY HEAVY RAINS LIKE TUESDAY.
STORMS SHOULD DIMINISH THIS EVENING AND TAPER OFF OR FADE AROUND
MIDNIGHT. A COLD FRONT APPROACHES TONIGHT FROM THE WEST AND SHOULD
REACH THE OHIO RIVER BY 8 AM THURSDAY MORNING. LOW LEVEL MOISTURE
AND LIGHT WINDS WILL RESULT IN AREAS OF FOG OVERNIGHT. LOWS WILL
RANGE FROM THE UPPER 60S TO LOWER 70S FOR MOST OF THE REGION.
A COLD FRONT WILL TRAVEL EAST ACROSS THE REGION THURSDAY INTO
THURSDAY EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP AHEAD AND ALONG THE FRONT. THE SWODY2 CONVECTIVE OUTLOOK
KEEPS OUR CWA IN THE GENERAL THUNDERSTORMS AND SPLITS THE MARGINAL
POTENTIAL TO OUR NORTH AND SOUTH. HIGH TEMPERATURES WILL CLIMB INTO
THE MID 70S IN THE NORTHWEST MOUNTAINS TO THE LOWER 90S IN THE
PIEDMONT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 230 PM EDT WEDNESDAY...
COLD FRONT WILL BE HEADING TO THE COAST THURSDAY EVENING FOLLOWED BY
COOLER HIGH PRESSURE THAT WILL BUILD IN FROM THE WEST THURSDAY NIGHT
INTO FRIDAY. LIKELY TO SEE A BAND OF POST FRONTAL TYPE SHALLOW
CONVECTION OVER THE PIEDMONT DURING THE EARLY EVENING GIVEN MODEST
FORECAST INSTABILITY BEFORE THE AXIS OF DEEP MOISTURE PUSHES TO THE
EAST AND OUT OF THE REGION BY MIDNIGHT. THUS LEAVING IN SOME LOW CHANCE
POPS EAST OF THE BLUE RIDGE BEFORE SEEING CLEARING AND COOLER WEATHER
ALL SECTIONS LATER THURSDAY NIGHT.
WITH 85H TEMPS FALLING TO BETWEEN +14-16C EXPECT QUITE A FEW LOW TEMPS
IN THE 50S TO AROUND 60 ACROSS THE VALLEYS WITH DRIER LOW/MID 60S OUT
EAST. A MAINLY SUNNY AND MUCH LESS HUMID FRIDAY LOOKS ON TAP UNDER GOOD
SUBSIDENCE AND LOW LEVEL NW FLOW. HOWEVER HEATING OF THE DRY AIR WILL
PUSH TEMPS BACK INTO THE LOW/MID 80S MOUNTAINS...AND STILL CLOSE TO 90
SE BUT WITH MUCH LESS HUMIDITY.
AFTER ANOTHER RATHER COOL MORNING SATURDAY...SHOULD SEE TEMPS REBOUND
SLIGHTLY SATURDAY AFTERNOON AS THICKNESS VALUES RISE A BIT AHEAD OF A
SECONDARY TYPE DRY BOUNDARY THAT WILL CROSS THE REGION LATE WITH
ANOTHER QUICK SHOT OF COOL ADVECTION INTO SATURDAY NIGHT. CANT TOTALLY
RULE OUT AN UPSLOPE SPRINKLE OVER NW SECTIONS LATE SATURDAY WHEN LOW
LEVEL NW FLOW WILL BE STRONGEST OTRW TOO DRY FOR MUCH MORE THAN SOME
CLOUDS AT BEST. THIS TO BE FOLLOWED BY YET ANOTHER COMFORTABLE
OVERNIGHT WITH TEMPS FALLING INTO THE 50S TO LOW 60S MOUNTAINS AND
LOW/MID 60S AGAIN OUT EAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 1230 PM EDT WEDNESDAY...
PREDOMINATE UPPER TROFFINESS ACROSS THE MID ATLANTIC WILL KEEP NW FLOW
ALOFT IN PLACE FROM THE WEEKEND THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. THIS SHOULD INITIALLY KEEP OVERALL DRY WEATHER IN PLACE WITH
SURFACE HIGH PRESSURE BUILDING ACROSS THE REGION FROM THE NW SUNDAY-
MONDAY...AND TO THE SOUTH AHEAD OF A REINFORCING COLD FRONT BY
WEDNESDAY. ONLY EXCEPTION TO THIS COULD BE WITH MOISTURE BEING LIFTED
BACK INTO THE SE EARLY NEXT WEEK WITH LOW PRESSURE DEVELOPING ALONG THE
RESIDUAL FRONT NEAR THE COAST. HOWEVER THE EARLIER ECMWF AND CMC ABOUT
THE ONLY SOLUTIONS THAT STILL HINT AT THIS SO BASICALLY LEAVING OUT
MOST POPS OUTSIDE OF SOMETHING ISOLATED SE SECTIONS ON MONDAY.
COLUMN WILL GRADUALLY MOISTEN ENOUGH BY MIDWEEK TO POSSIBLY SUPPORT A
BIT MORE CONVECTION AS WEAK SHORTWAVES ALOFT TRAVERSE THE NW FLOW ON
TUESDAY AHEAD OF A STRONGER UPPER LOW AND COLD FRONT TO THE NORTH
WEDNESDAY. GUIDANCE REMAINS A BIT HESITANT TO PRODUCE MUCH IN THE WAY
OF PRECIP GIVEN MAIN LIFT TO THE NORTH BUT APPEARS ENOUGH FOCUS WITH
HEATING TO SUPPORT SOME LOW POPS TUESDAY AFTERNOON. BETTER CHANCES MAY
COME WEDNESDAY AS THE FRONT SAGS TOWARD THE AREA FROM THE NORTH AND
DEWPOINTS RISE BUT EVEN THEN SUPPORT THIS FAR SOUTH LACKING SO CHANCE
POPS IN ORDER. OTRW MAINLY A PERSISTENCE FORECAST WITH HIGHS 80S TO
AROUND 90 SE AND 60S OVERNIGHT EXCEPT SOME COOLER 50S VALLEYS EARLY IN
THE WEEK AS DEWPOINTS/HUMIDITY REMAIN LOW.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 800 PM EDT WEDNESDAY...
AREA RADARS SHOWED ISOLATED SHOWERS AND THUNDERSTORMS OVER WEST
VIRGINIA...SOUTHWEST VIRGINIA AND NORTHWEST NORTH CAROLINA THIS
EVENING. SOME OF THE RAIN WAS CLOSE TO THE LOCAL AIRPORTS...BUT
NOT CLOSE ENOUGH TO INCLUDE IN THE TAFS AT THIS TIME.
AIR MASS REMAINS VERY MOIST AT LOW LEVELS TONIGHT. HIGH CONFIDENCE
FOR THE DEVELOPMENT OF MVFR FOG BY MIDNIGHT. COVERAGE OF SHOWERS
AND THUNDERSTORMS WILL REMAIN ISOLATED UNTIL THE FRONT APPROACHES
THE APPALACHIANS AFTER 10Z/6AM. IFR TO LIFR FOG IS ALSO EXPECTED
AT KBCB AND KLWB.
MODELS...INCLUDING DIFFERENT VERSIONS OF THE HRRR SUGGESTS SOME PREFRONTAL
SHOWERS AND THUNDERSTORMS MAY MOVE INTO THE MOUNTAINS AFTER
MIDNIGHT...BUT THAT THERE WILL BE LITTLE TO PRECIPITATION ALONG
THE ACTUAL FRONT. THUNDERSTORMS MAY DEVELOP ALONG THE BOUNDARY
EAST OF THE BLUE RIDGE SO HAVE INCLUDED VC IN THE KLYH AND KDAN
TAFS FOR THURSDAY AFTERNOON.
A MUCH DRIER AIR MASS COMES INTO THE REGION BEHIND THE FRONT BY
THURSDAY NIGHT.
EXTENDED AVIATION FORECAST...
BEHIND THE FRONT THE WEATHER WILL BE DRY AND VFR FRIDAY THROUGH
SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...KK
SHORT TERM...JH
LONG TERM...JH
AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
305 PM EDT TUE JUL 28 2015
.SYNOPSIS...
A DIFFUSE FRONTAL BOUNDARY WILL LINGER ACROSS THE REGION THROUGH
WEDNESDAY BEFORE ANOTHER STRONGER COLD FRONT ARRIVES FROM THE
NORTHWEST THURSDAY. SCATTERED SHOWERS AND THUNDERSTORMS WILL
CONTINUE IN THE FORECAST UNTIL THE SECONDARY FRONT MOVES SOUTH OF
THE REGION FRIDAY. SOMEWHAT DRIER AIR SHOULD FOLLOW THE FRONT FOR THE
WEEKEND AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 205 PM EDT TUESDAY...
CLUSTERS OF DEEPER CONVECTION CONTINUE OVER THE SE ALONG AN AXIS
OF HIGHER SURFACE BASED THETA-E/INSTABILITY AND OVER THE NW IN
ASSOCIATION WITH THE RESIDUAL FRONT AND A WEAK WAVE ALOFT. MODELS
AGAIN STRUGGLING WITH WHERE TO PAINT THE BEST CONVECTIVE COVERAGE
INTO TONIGHT GIVEN WEAK FEATURES AND DIURNAL NATURE OF MORE
OUTFLOW DRIVEN STORMS. HOWEVER SOME CONSENSUS OFF THE HRRR AND
ENSEMBLES AS WELL AS THE GFS TO HAVE BEST HEAVY RAIN PRODUCING
SHRA/TSRA OVER THE EAST AS THE WEAK SHORTWAVE TO THE NW DROPS
THROUGH THE REGION GIVEN LINGERING INSTABILITY WELL INTO THE
EVENING. THIS AREA THOUGH MAY BE TOO WORKED OVER BY THEN SO WILL
TREND WITH HIGHER POPS THERE AFTER SUNSET BUT MAINLY OF THE HIGH
CHANCE VARIETY AS ADDED PRECIP AFTER DARK MAY BE VOID OF DEEP
CONVECTION. OTRW KEEPING THE SCATTERED NATURE REGIME GOING THROUGH
ABOUT MIDNIGHT WEST...AND PERIODS OF LIKELYS OR HIGHER OUT EAST A
WHILE LONGER BEFORE CUTTING TO PC/FOG LATE. AGAIN QUITE WARM/MUGGY
WITH MANY EASTERN LOCATIONS STAY ABOVE 70 UNLESS SPOTS SEE A COOLING
SHOWER INTO THIS EVENING.
5H HEIGHTS WILL BUILD A BIT ON WEDNESDAY AS THE AREA REMAINS IN A
MOISTURE LADEN ENVIRONMENT UNDER WEAK SURFACE HIGH PRESSURE BUT WITH
LESS FOCUS GIVEN THE WASHING OUT OF THE NEARBY FRONT. GUIDANCE SHOWS
SOME CONVERGENCE ACROSS THE RIDGES DURING THE AFTERNOON ESPCLY AS THE
FLOW TURNS MORE SW ALOFT WHICH SHOULD HELP FOCUS ADDED CONVECTION ALONG
THE RIDGES. HOWEVER WITH THE NEXT UPSTREAM SHORTWAVE TROUGH WELL TO THE
NW WITH THE NEXT COLD FRONT...APPEARS LIFT WILL BE LESS BUT LIKELY
ENOUGH GIVEN STRONG INSTABILITY TO RESULT IN SCATTERED COVERAGE
MOUNTAINS AND A BIT LESS IN THE EAST. STEERING REMAINS ON THE
WEAK SIDE SO MAIN THREAT AGAIN WITH HEAVY RAINFALL. HIGH TEMPS IN
LINE WITH THE LATEST MAV/MOS MIX SO ONLY MADE SMALL TWEAKS TO BUMP
UP VALUES A LITTLE IN THE EAST WHERE SOME LOW 90S POSSIBLE. OTRW
MUGGY 80S IN STORE.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 PM EDT TUESDAY...
SCATTERED SHOWERS AND THUNDERSTORMS WILL DIMINISH WEDNESDAY EVENING
INTO WEDNESDAY NIGHT. A COLD FRONT WILL APPROACH FROM THE WEST LATE
WEDNESDAY NIGHT INTO THURSDAY MORNING. LOW TEMPERATURES WEDNESDAY
NIGHT WILL RANGE FROM THE MID 60S IN THE MOUNTAINS TO LOWER 70S IN
THE PIEDMONT.
THE COLD FRONT WILL PUSH EAST ACROSS OUR AREA THURSDAY INTO THURSDAY
NIGHT. AS HIGHLIGHTED IN SPC MARGINAL RISK...SOME STRONG TO SEVERE
THUNDERSTORMS WILL BE POSSIBLE THURSDAY AFTERNOON AND EARLY EVENING.
THE GREATEST THREAT WILL BE FOR PULSE SEVERE THUNDERSTORMS WITH
DOWNBURST/LOCALIZED WIND DAMAGE POTENTIAL AS LOW-LEVEL LAPSE RATES
STEEPEN THURSDAY AFTERNOON. THE SLIGHTLY STRONGER MID-LEVEL FLOW
SHOULD REDUCE THE FLOOD POTENTIAL. HIGH TEMPERATURES THURSDAY WILL
VARY FROM THE MID 70S IN THE NORTHWEST MOUNTAINS TO THE LOWER 90S IN
THE PIEDMONT. PLACED THE HIGHEST POPS IN THE EAST THURSDAY NIGHT.
LOW TEMPERATURES THURSDAY NIGHT WILL DROP INTO THE LOWER 60S IN THE
MOUNTAINS TO THE LOWER 70S IN THE PIEDMONT.
THE AMPLIFICATION OF THE SUBTROPICAL RIDGE INTO THE SOUTHWEST U.S.
WILL RESULT IN STRENGTHENING NORTHWEST FLOW ALOFT ACROSS THE EAST
COAST. THIS WILL PUSH THE COLD FRONT FURTHER SOUTH BEFORE STALLING
IN SOUTHEAST LATE FRIDAY. COOLER HIGHS EXPECTED FRIDAY WITH READINGS
FROM THE MID 70S IN THE NORTHWEST MOUNTAINS TO THE UPPER 80S IN THE
PIEDMONT. LOWS TEMPERATURES FRIDAY NIGHT WILL VARY FROM THE UPPER
50S IN THE WEST TO THE MID 60S IN THE EAST.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 PM EDT TUESDAY...
A GOOD WEEKEND EXPECTED WITH DRY SEASONABLE TEMPERATURES AND
HUMIDITY LEVELS...AS HIGH PRESSURE BUILD EAST OUT OF THE OHIO VALLEY.
THERE ARE SEVERAL OTHER KEY PLAYERS IN THE MEDIUM RANGE FORECAST
ESPECIALLY THE DEEPENING UPPER TROUGH AND PSEUDO-TROPICAL LOW. A
BROAD UPPER TROUGH IS PROGGED TO REMAIN ACROSS EASTERN CANADA AND
SHOULD DEEPEN INTO THE EASTERN UNITED STATES....THEN FLATTEN OUT
EARLY NEXT WEEK. ANOTHER CONCERN FOR THIS PERIOD WILL BE AN AREA OF
LOW PRESSURE WHICH DEVELOPS ACROSS FLORIDA OR IN THE GULF AND THE
INTERACTION WITH STALLED FRONTAL BOUNDARY LOCATED ACROSS THE
SOUTHEAST STATES.
WITH RESPECT TO THE PSEUDO-TROPICAL LOW DEVELOPING ACROSS THE
EASTERN GULF AND SOUTHEAST STATES...MODELS ARE IN BETTER AGREEMENT
WITH THE UPPER TROUGH. THE ECMWF REMAINS THE MOST ROBUST COMPARED
TO OTHER SOLUTIONS IN DEVELOPING A CLOSED SFC LOW...AND THEN
TRACKING IT NORTHEAST ALONG THE SOUTHEAST COAST INTO EARLY NEXT
WEEK.
QUESTIONS REMAIN IN THE FORECAST ON WHETHER A WEAK FRONTAL BOUNDARY
EARLY NEXT WEEK COULD PULL THE SOUTHEAST LOW PRESSURE CENTER AND ITS
ASSOCIATED MOISTURE FURTHER INLAND ACROSS THE PIEDMONT OR BLOCK IT
EAST OF THE AREA. IN ANY CASE...THE CHANCE FOR RAIN WILL BE
INCREASING HEADING INTO EARLY NEXT WEEK. THE LOCATIONS WITH THE
BETTER CHANCE OF RAIN WILL BE ACROSS THE PIEDMONT.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AS OF 1235 PM EDT TUESDAY...
OVERALL SHOTGUN PATTERN TO DEVELOPING CONVECTION WILL CONTINUE
THROUGH MID AFTERNOON BEFORE PERHAPS SHRA/TSRA ORGANIZES A BIT
MORE AND HEADS EAST OFF THE BLUE RIDGE. HOWEVER STILL TOO IFFY TO
INCLUDE PREVAILING CONVECTION AT ANY ONE TAF SITE PENDING RELEASE
SO KEEPING MOSTLY VCTS GOING AT MOST LOCATIONS INTO EARLY THIS
EVENING. COULD BE ENOUGH COVERAGE THIS EVENING FOR MORE OF A
PREVAILING MVFR GROUP IN SHOWERS OUT EAST BUT LOW CONFIDENCE. OTRW
EXPECT MOST SITES TO FINALLY IMPROVE TO VFR LEVELS OUTSIDE OF
CONVECTION EARLY THIS AFTERNOON WITH LOCALIZED MVFR/IFR IF A
HEAVIER SLOW MOVING SHRA/TSRA MOVES OVER OR NEAR A TAF LOCATION
DURING THE NEXT FEW HOURS.
SHOWERS MAY LINGER WELL PAST MIDNIGHT TONIGHT ESPCLY IN THE EAST
WITH A WEAK WAVE PASSING. THIS SHOULD GRADUALLY TREND TOWARD MORE
FOG IN THE VALLEYS AND WHERE HEAVIER RAINFALL OCCURRED LATE. THIS
SUPPORTS IFR/LIFR IN THE VALLEY SPOTS SUCH AS KLWB/KBCB AND
OVERALL MVFR ELSW WITH EVEN SOME FOG POSSIBLE AT KROA IF THEY SEE
AFTERNOON/EVENING RAINFALL.
WEDNESDAY WILL BE ANOTHER DAY OF MVFR TO IFR VALLEY FOG IN THE
MORNING AND SCATTERED AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS. HOWEVER COVERAGE MAY BE LESS AND MORE
OROGRAPHIC/OUTFLOW DRIVEN WEDNESDAY AFTERNOON WITH AGAIN LOCAL
SUB-VFR IN AND NEAR ANY CONVECTION.
EXTENDED AVIATION FORECAST...
MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED ON THURSDAY
AS A COLD FRONT CROSSES THROUGH REGION FROM THE NORTHWEST. THIS
FRONT SHOULD PUSH SOUTH OF THE AREA AND ALLOW FOR DRIER AND MOSTLY
VFR CONDITIONS FRIDAY THROUGH SUNDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/RAB
NEAR TERM...JH
SHORT TERM...KK
LONG TERM...KK
AVIATION...AMS/JH/MBS/RAB
AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION CAN BE SEEN AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
Area Forecast Discussion
National Weather Service Spokane WA
224 PM PDT TUE JUL 28 2015
.SYNOPSIS....
Summer conditions return to the Inland Northwest as a ridge of
high pressure takes control. Dry and increasingly hot weather
pattern will persist through the weekend across the Inland
Northwest. The only chance of precipitation in the near future
will be a small chance of showers or thunderstorms over extreme
southeast Washington and north-central Idaho during the weekend.
&&
.DISCUSSION...
Tonight through Wednesday...Not much going on during this period
as upper level jet...currently extending from the dateline into
northeast BC...buckles a little northward during the next 24-36
hours. What will this do to the weather? The main impacts will be
drying and warming trend. It will also stabilize the atmosphere so
the widespread but shallow cumulus clouds seen this afternoon on
visible satellite will begin to wane this evening and should be
far less prevalent by Wednesday afternoon. The increased sunshine
combined warming temperatures aloft should translate to high
temperatures poking back into the mid 80s and 90s for most
locations. fx
Wednesday night through Tuesday...The Inland Northwest is headed for
an extended period of hot and dry weather as a ridge of high
pressure takes up residence over the region. Temperatures will be on
an upward trend with most valley locations in the 90s to low triple
digits through at least the weekend. The only sensible weather of
note will be breezy winds down the Cascade gap valleys that will
initiate after sunset each day. Whether these winds will be strong
enough to reach critical fire weather conditions when combined with
very low minimum relative humidity is a low confidence forecast. The
other concern will be the possibility of isolated thunderstorms
developing over the northeast Blue Mts and Camas Prairie as
monsoonal moisture drifts up from the south. Right now it looks like
convection will remain south of the forecast area. A nominal area of
slight chance thunderstorms remains in the weather grids to cover
this possibility. /Kelch
&&
.AVIATION...
18Z TAFS: Building ridge will deliver VFR conditions and generally
clear skies to all forecast sites through late Wednesday morning.
Winds will be generally light and terrain driven. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 56 87 62 94 64 97 / 0 0 0 0 0 0
Coeur d`Alene 54 87 58 92 58 95 / 0 0 0 0 0 0
Pullman 49 87 55 94 56 96 / 0 0 0 0 0 0
Lewiston 58 95 65 102 68 104 / 0 0 0 0 0 0
Colville 52 90 55 95 57 99 / 0 0 0 0 0 0
Sandpoint 47 84 51 89 51 93 / 0 0 0 0 0 0
Kellogg 49 85 55 91 56 95 / 0 0 0 0 0 0
Moses Lake 58 95 61 100 63 101 / 0 0 0 0 0 0
Wenatchee 62 96 68 100 69 101 / 0 0 0 0 0 0
Omak 54 94 60 98 61 101 / 0 0 0 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Spokane WA
1051 AM PDT TUE JUL 28 2015
.SYNOPSIS....
With the exit of the storm system that brought scattered showers
and thunderstorms to the area last evening a return to summer
conditions will commence today. A dry and increasingly hot weather
pattern will persist through next weekend across the inland
northwest.
&&
.DISCUSSION...
Rest of today...Strong upper level low currently over southern
Saskatchewan will continue to eject eastward through the day.
Zonal or westerly flow will replace its presence over the region
today. This will equate to dry and warming weather for most
locations. The latest water vapor loops show a weak n-s oriented
deformation band extending from SE BC through NE Oregon. We don`t
expect to see much weather from this other than some variable high
clouds as it passes eastward through the region. With upper level
temperatures warming significantly today, we don`t expect to see
much chance of deep convection...however the HRRR continues to
paint a few sprinkles near the Canadian border by mid-afternoon.
Model soundings in that area really don`t support that notion
however the dewpoints across far northern Washington and north
Idaho are running more moist than the models suggest so we will
leave the threat in the forecast for the mid/late afternoon hours.
fx
&&
.AVIATION...
18Z TAFS: Building ridge will deliver VFR conditions and generally
clear skies to all forecast sites through late Wednesday morning.
Winds will be generally light and terrain driven. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 79 56 87 62 93 65 / 0 0 0 0 0 0
Coeur d`Alene 78 52 87 57 92 58 / 0 0 0 0 0 0
Pullman 77 53 87 54 93 56 / 0 0 0 0 0 0
Lewiston 84 56 95 64 101 68 / 0 0 0 0 0 0
Colville 81 52 90 53 95 56 / 10 0 0 0 0 0
Sandpoint 76 49 84 49 89 50 / 0 0 0 0 0 0
Kellogg 76 49 85 55 91 56 / 0 0 0 0 0 0
Moses Lake 85 56 94 60 99 63 / 0 0 0 0 0 0
Wenatchee 85 56 95 66 99 68 / 0 0 0 0 0 0
Omak 85 52 94 58 98 60 / 0 0 0 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
331 PM CDT TUE JUL 28 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT TUE JUL 28 2015
LATEST WATER VAPOR SATELLITE IMAGERY SHOWS VIGOROUS SHORTWAVE TROUGH
OVER EASTERN IOWA AND SOUTHERN WISCONSIN. LATEST MOSAIC RADAR
INDICATING SHOWERS/THUNDERSTORMS HAVE WEAKENED WITH THE SHORTWAVE
TROUGH EARLY THIS AFTERNOON. LATEST 19Z SURFACE ANALYSIS SHOWING
COLD FRONT EXTENDING FROM WESTERN MINNESOTA INTO EASTERN NEBRASKA.
MAIN FORECAST CONCERNS TONIGHT ARE PRECIPITATION CHANCES AND
POTENTIAL FOR SEVERE THUNDERSTORMS THIS EVENING. WITH THE
SHORTWAVE TROUGH AND ASSOCIATED PRECIPITATION/CLOUDS OVER THE
FORECAST AREA MUCH OF TODAY...THIS HAS ALLOWED THE ATMOSPHERE TO
BE CAPPED OVER THE FORECAST AREA. THIS IS EVIDENT WITH THE LATEST
28.18Z RAP BUFKIT SOUNDINGS INDICATING A STRONG INVERSION OVER
MUCH OF THE FORECAST AREA. IN ADDITION...THE LATEST 28.17Z
HRRR/HOPWRF SHOW VERY LITTLE CONVECTION TO DEVELOP ALONG THE COLD
FRONT...DUE TO LACK OF CONVERGENCE ALONG FRONT...AND HINT AT
POSSIBLE DEVELOPMENT OF ISOLATED SHOWER/THUNDERSTORM MAINLY EAST
OF THE MISSISSIPPI RIVER AFTER 00Z WEDNESDAY. THE HRRR/HOPWRF
INDICATE SHOWER/THUNDERSTORM DEVELOPMENT SOUTH OF FORECAST AREA IN
CENTRAL IOWA...WHERE BETTER MOISTURE CONVERGENCE AND LIFT IS ALONG
OUTFLOW BOUNDARY FROM THIS MORNINGS MCS. DUE TO THE LOSS OF
INSTABILITY/FORECAST AREA CAPPED AND LACK OF MOISTURE CONVERGENCE
ALONG FRONT...HAVE REDUCED PRECIPITATION CHANCES ACROSS THE
FORECAST AREA THIS EVENING/TONIGHT. PLUS...WITH THE BETTER
LIFT/MOISTURE CONVERGENCE AND INSTABILITY SOUTH OF THE FORECAST
AREA. SEVERE WEATHER THREAT WILL BE CONFINED TO THE FAR SOUTHERN
PART OF THE FORECAST AREA OR SOUTH OF THE FORECAST AREA.
UPPER LEVEL TROUGH DIGS INTO THE GREAT LAKES REGION AND PRESSURE
GRADIENT TIGHTENS BEHIND COLD FRONT ACROSS THE FORECAST AREA
WEDNESDAY. THE 28.12Z GFS/NAM BUFKIT SOUNDINGS SUGGEST AREA WILL
MIX UP TO AROUND 800MB AND WINDS AT THIS LEVEL INCREASE TO AROUND
30 KNOTS. HAVE INCREASED WINDS/WIND GUSTS ACROSS THE FORECAST
AREA...ESPECIALLY IN THE HIGHER TERRAIN AND OPEN AREAS WEDNESDAY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 331 PM CDT TUE JUL 28 2015
SURFACE RIDGE BUILDS INTO THE CENTRAL PLAINS THURSDAY INTO FRIDAY.
WITH SUBSIDENCE UNDERNEATH HIGH AND MAIN SHORTWAVE ENERGY OVER
LAKE SUPERIOR AND SOUTHERN CANADA...FORECAST AREA WILL REMAIN DRY
THROUGH THE END OF THE WEEK.
MAIN FORECAST CONCERNS FRIDAY NIGHT INTO TUESDAY ARE PRECIPITATION
CHANCES THROUGH THE PERIOD. THE 28.12Z GFS/ECMWF/GEM ARE IN
DECENT AGREEMENT IN DIGGING UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION THROUGH 00Z SUNDAY...THEN DIVERGE ON THE STRENGTH OF
THE UPPER LEVEL TROUGH. WHERE THE 28.12Z GFS/GEM ARE STRONGER
WITH THE UPPER LEVEL TROUGH OVER THE GREAT LAKES REGION THAN THE
ECMWF. THE 28.12Z GFS/GEM/ECMWF INDICATE DIFFERENCES IN TIMING OF
SHORTWAVE TROUGHS EMBEDDED IN THE NORTHWEST FLOW ALOFT OVER THE
GREAT LAKES REGION. THE 28.12Z GFS/GEM/ECMWF SUGGEST ENOUGH LIFT
AND MOISTURE CONVERGENCE IN ASSOCIATION WITH EACH SHORTWAVE TROUGH
TO WARRANT CHANCES OF SHOWERS/THUNDERSTORMS ACROSS MUCH OF THE
FORECAST AREA FROM SATURDAY NIGHT INTO TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1218 PM CDT TUE JUL 28 2015
VSBYS IMPROVING/GOOD AT BOTH TAF SITES FOR THE AFTERNOON AS THE
FIRST BAND OF SHRA/TSRA WEAKENS/EXITS. LOW LEVEL MOISTURE AND
OUTFLOW BEHIND THE DISSIPATING BAND OF SHRA/TSRA PRODUCING SOME MVFR
STRATO-CU ACROSS THE AREA THRU THE EARLY AFTERNOON HOURS. WITH
DIURNAL WARMING/MIXING THIS SHOULD MIX/LIFT TO A SCT VFR DECK BY MID
AFTERNOON...WITH SOME BRISK SOUTHEAST TO SOUTH WINDS. CONSIDERABLE
UNCERTAINTY REMAINS WITH THE CHANCES OF MORE SHRA/TSRA AT THE TAF
SITES THIS EVENING. TIMING OF 01-04Z AT KRST AND 03-06Z AT KLSE
APPEARS REASONABLE. HOWEVER...LOOKING LIKE THIS MAY COME ACROSS THE
AREA AS MORE OF A LINE OF SCT SHRA/TSRA AND LEFT MENTION OF IT AS
VCTS/CB IN BOTH TAFS. DRIER PUSHES IN BEHIND THE COLD FRONT LATER
THIS EVENING/OVERNIGHT...WITH GENERALLY GOOD VFR EXPECTED ONCE ANY
SHRA/TSRA IN THE LINE/NEAR THE FRONT WOULD EXIT THE AREA.
TIGHTER PRESSURE GRADIENT OVER THE AREA WED. WITH MODEL SOUNDINGS
SHOWING MIXING TO 800MB WED AFTERNOON...BRISK/GUSTY WEST TO
NORTHWEST WINDS 15-20KT G25-30KTS EXPECTED BY LATE WED MORNING AND
FOR WED AFTERNOON.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION.....RRS
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 251 PM CDT TUE JUL 28 2015
SHOWERS AND STORMS RAPIDLY DISSIPATED EARLY THIS AFTERNOON AS THEY
MOVED EAST INTO CENTRAL WISCONSIN. MEANWHILE...A COLD FRONT WAS
LOCATIONS ACROSS WESTERN MINNESOTA. SHOWERS AND STORMS ARE
EXPECTED TO DEVELOP ALONG THE FRONT LATER THIS AFTERNOON AND THIS
EVENING...AND THEN MOVE ACROSS NORTH-CENTRAL AND NORTHEAST
WISCONSIN LATER THIS EVENING AND OVERNIGHT.
THE SEVERE WEATHER POTENTIAL LOOKS VERY LOW AS BEST 0-6KM SHEAR
LAGS BEHIND THE FRONT. HOWEVER...THIS IS THE TIME OF YEAR FOR
WET MICROBURSTS...THUS WILL MENTION GUSTY WINDS AND LOCALLY
HEAVY RAINFALL IN THE HAZARDOUS WEATHER OUTLOOK. FORMAL SPOTTER
ACTIVATION IS NOT ANTICIPATED...BUT SPOTTERS ARE REQUESTED TO
REPORT RAINFALL AMOUNTS OVER AN INCH OR WIND GUSTS OVER 40 MPH.
KIND OF AN UNUSUAL EVENT FOR LATE JULY WILL TAKE PLACE ON
WEDNESDAY. STRONG LOW PRESSURE ACROSS SOUTHERN CANADA WILL MOVE
EAST TOWARDS HUDSON BAY. TIGHT PRESSURE GRADIENT AND STRONGER
WINDS ALOFT SUPPORT WIND GUSTS OF 30 TO 35 MPH POSSIBLE. MIXING
HEIGHTS ON THE BUFKIT SOUNDINGS INDICATED BETWEEN FIVE AND EIGHT
THOUSAND FEET...WHICH COULD TAP WINDS AS STRONG AS 35 KNOTS. DID
INCREASE WINDS ON WEDNESDAY TO ACCOUNT FOR DEEP MIXING AND
STRONGER WINDS ALOFT. BASED ON TEMPERATURES UPSTREAM...BELIEVE
GUIDANCE IS TOO WARM FOR HIGHS ON WEDNESDAY.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 251 PM CDT TUE JUL 28 2015
THE TIMING OF A COLD FRONT AND ASSOCIATED PCPN CHANCES OVER THE
WEEKEND IS THE MAIN FCST CONCERN.
THE REGION WILL REMAIN IN A FAST ZONAL WEST-NORTHWEST FLOW PATTERN
THROUGH MOST OF THE PERIOD...WITH A SERIES OF S/W TROFS BRUSHING
NORTHERN WI...AND FRONTAL PASSAGES EVERY COUPLE DAYS.
THERE IS GOOD MODEL AGREEMENT ON A WEAK COLD FRONT MOVING THROUGH
THE AREA THURSDAY NIGHT INTO FRIDAY. HAVE ADDED A SMALL POP OVER
NORTHERN WI LATE THU NGT...WHEN THE FRONT AND A S/W TROF MAY
COMBINE TO PRODUCE ISOLD/SCT LIGHT SHOWERS.
WEAK HIGH PRESSURE WILL PUSH ACROSS THE WESTERN GREAT LAKES ON
FRIDAY NIGHT AND SATURDAY...BRINGING DRY CONDITIONS.
FCST GETS A BIT MUDDLED OVER THE WEEKEND AND BEYOND...AS MODELS
HAVE TRENDED SLOWER WITH A COLD FRONTAL PASSAGE. THE ECMWF HAS
NOT ONLY SLOWED THE FRONT DOWN CONSIDERABLY...BUT IS ALSO SHOWING
A WEAKER FEATURE THAN YESTERDAY. WILL LEAN TOWARD THE GFS...WHICH
HAS A STRONGER AND MORE PROGRESSIVE FRONTAL PASSAGE LATE SATURDAY
NIGHT INTO SUNDAY. THERE IS ALSO CONCERN ABOUT WHERE THE FRONT
WILL RESIDE AFTER IT MOVES THROUGH...AND WHETHER IT WILL REMAIN
CLOSE ENOUGH TO GENERATE ADDITIONAL PCPN EARLY NEXT WEEK...
ESPECIALLY OVER OUR SOUTHERN AND EASTERN COUNTIES. WILL CONTINUE
TO FOCUS HIGHEST POPS ON SATURDAY NIGHT/SUNDAY PERIOD FOR NOW...
BUT THIS MAY BE SUBJECT TO CHANGE WITH SUBSEQUENT FCSTS.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1233 PM CDT TUE JUL 28 2015
VFR CONDITIONS WILL PREVAIL THIS AFTERNOON WITH SOUTH WINDS
GUSTING TO NEAR 20 KNOTS AWAY FROM THE LAKE. COLD FRONT EXPECTED
TO MOVE ACROSS THE REGION LATE THIS EVENING AND OVERNIGHT...
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. TRIED TO TIME
THE BEST CHANCES FOR STORMS IN THE 18Z TAFS...BUT NEW HRRR MODEL
EVEN A TAD BIT SLOWER. SOMEWHAT UNUSUAL EVENT EXPECTED FOR LATE
JULY. GUSTY WEST WINDS COULD GUST AS HIGH AS 30 TO 35 KNOTS IF
WE CAN MIX TO NEAR 5000 THOUSAND FEET AS SYSTEM MOVES ACROSS
CANADA. WINDS WILL GRADUALLY DECREASE LATE WEDNESDAY AFTERNOON
AND EVENING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....ECKBERG
LONG TERM......KIECKBUSCH
AVIATION.......ECKBERG
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1241 PM CDT TUE JUL 28 2015
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 315 AM CDT TUE JUL 28 2015
A SQUALL LINE ACROSS THE EASTERN DAKOTAS IS SLOWLY MAKING ITS WAY
WESTWARD TOWARDS WISCONSIN THIS MORNING. HOWEVER...AS EVIDENCED BY
THE 00Z KGRB RAOB...THESE STORMS WILL BE RUNNING INTO A WALL OF
VERY DRY AIR ACROSS CENTRAL WISCONSIN. THIS IS CAPTURED RATHER
WELL WITH THE HI-RES MODEL RUNS AS THE LINE OF THUNDERSTORMS
DISSIPATES AS IT TRACKS INTO CENTRAL AND NORTH CENTRAL WISCONSIN
THIS AFTERNOON. GIVEN THE HIGH DEGREE OF MODEL AGREEMENT WILL PUSH
BACK AND LOWER POPS SIGNIFICANTLY ACROSS THE CWA TODAY...LIMITING
POPS TO THE WEST IN CASE SOME OF THE ACTIVITY SPILLS INTO THE
WESTERN CWA. IF THIS ACTIVITY DOES MAKE IT...THERE COULD BE GUSTY
WINDS WITH THE LINE OF THUNDERSTORMS...ESPECIALLY ACROSS CENTRAL
WISCONSIN...WHICH PUTS THE AREA IN THE MARGINAL RISK ACCORDING TO
THE SPC OUTLOOK. GIVEN THE LATER ARRIVAL OF THE ACTIVITY...AND
LACK OF ACTIVITY EXPECTED ACROSS THE EASTERN CWA...WILL RAISE HIGH
TEMPERATURES SEVERAL DEGREES TOWARDS MOS GUIDANCE VALUES AS HIGHS
GET INTO THE MIDDLE TO UPPER 80S.
PRECIPITATION CHANCES TONIGHT STILL LOOK FAIRLY GOOD...IN THE
LIKELY CATEGORY...AS A COLD FRONT SWEEPS THROUGH THE WESTERN GREAT
LAKES REGION. DRY AIR WILL STILL BE IN PLACE...WITH HI-RES MODEL
RUNS INDICATING THE ACTIVITY TONIGHT COULD BE SPOTTY INSTEAD OF A
SOLID LINE OF SHOWERS AND THUNDERSTORMS. GIVEN THE DRY AIR IN
PLACE AND THE LESS THAN ENCOURAGING HI-RES MODEL RUNS WILL NOT
RAISE POPS BEYOND LIKELY WITH THIS FORECAST ISSUANCE. SOME OF
THESE STORMS COULD PRODUCE GUSTY WINDS AND SMALL HAIL AS MUCAPES
APPROACH 1000 J/KG...WHICH WILL CONTINUE THE MARGINAL THREAT FOR
SEVERE WEATHER OVERNIGHT.
CLEARING SKIES BEHIND THE COLD FRONT ARE EXPECTED ON WEDNESDAY AS
A TIGHT PRESSURE GRADIENT BRINGS GUSTY WESTERLY WINDS TO 30 MPH
ACROSS THE CWA. HIGHS ON WEDNESDAY WILL BE COOLER IN THE UPPER 70S
TO LOWER 80S AS DEW POINTS FALLING INTO THE 50S MAKE CONDITIONS
MORE COMFORTABLE THAN THE LAST FEW DAYS.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 315 AM CDT TUE JUL 28 2015
UPPER-LEVEL LOW WILL ESSENTIALLY REMAIN IN PLACE IN THE VICINITY
OF HUDSON BAY...WHILE BROAD UPPER-LEVEL RIDGING GRADUALLY TAKES
CONTROL OVER THE INTERMOUNTAIN WEST DURING THE EXTENDED PORTION OF
THE FORECAST. THIS PATTERN WILL KEEP THE WESTERN GREAT LAKES IN A
GENERAL NORTHWEST FLOW THROUGH THE UPCOMING WEEKEND. EMBEDDED
GENERALLY WEAK SHORTWAVE IMPULSES TRAVERSING THE NORTHERN CONUS
FROM TIME TO TIME WILL OFFER QUICK SHOTS AT SOME RATHER MODEST
PRECIPITATION ESPECIALLY LATER IN THE WEEKEND. TEMPERATURES SHOULD
REMAIN AT OR ABOVE NORMAL INTO THE FIRST PART OF NEXT WEEK WITH
EVIDENCE IN SOME OF THE MEDIUM RANGE GUIDANCE FOR A MORE NOTABLE
COOL DOWN THEREAFTER.
AS PRIMARY SHORTWAVE TROUGH HEADS NORTHEAST TOWARD HUDSON BAY
WEDNESDAY NIGHT...SUBSIDENCE AND A BRIEF PUSH OF SOMEWHAT COOLER
AND NOTICEABLY DRIER CANADIAN AIR SHOULD MAKE ITS WAY ACROSS THE
WESTERN GREAT LAKES. THURSDAY LOOKS LIKE A BREEZY AND SEASONABLY
WARM DAY WITH MORE COMFORTABLE DEWPOINTS IN THE 50S.
FIRST IN SERIES OF WEAK UPPER-LEVEL IMPULSES APPROACHES THE
WESTERN GREAT LAKES FRIDAY MORNING. CONSENSUS OF MODEL GUIDANCE
SUGGESTS BULK OF THE UPPER FORCING WILL PASS NORTH OF THE FORECAST
AREA AND MOISTURE ASSOCIATED WITH FROPA WILL BE QUITE LIMITED.
THUS SEE NO REASON TO DEVIATE FROM DRY FORECAST FOR FRIDAY. WEAK
SURFACE HIGH PRESSURE RIDGE WILL FOLLOW THE FROPA THUS SATURDAY
SHOULD REMAIN DRY AS PER PREVIOUS FORECAST.
MORE SUBSTANTIAL SHORTWAVE DISTURBANCE BEGINS TO IMPACT THE
FORECAST AREA LATE SATURDAY NIGHT OR SUNDAY. BOTH THE ECMWF AND
GFS WERE IN THE BALL PARK ON TIMING OF FROPA IN THE SUNDAY
MORNING TIME PERIOD. ALTHOUGH MOISTURE STILL APPEARS RATHER
LIMITED...UPPER FORCING SHOULD BE SUFFICIENT TO GENERATE AT LEAST
SCATTERED CONVECTION. BEYOND SUNDAY...ADDITIONAL WEAK DISTURBANCES
WITHIN NORTHWEST FLOW CONTINUE THUS WILL NOT DEVIATE FROM MODEL
BLEND WHICH GIVES LOW END POPS FOR THE FIRST WEEK OF AUGUST WITH
TEMPERATURES TRENDING TOWARD BELOW NORMAL FOR EARLY AUGUST. &&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1233 PM CDT TUE JUL 28 2015
VFR CONDITIONS WILL PREVAIL THIS AFTERNOON WITH SOUTH WINDS
GUSTING TO NEAR 20 KNOTS AWAY FROM THE LAKE. COLD FRONT EXPECTED
TO MOVE ACROSS THE REGION LATE THIS EVENING AND OVERNIGHT...
BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. TRIED TO TIME
THE BEST CHANCES FOR STORMS IN THE 18Z TAFS...BUT NEW HRRR MODEL
EVEN A TAD BIT SLOWER. SOMEWHAT UNUSUAL EVENT EXPECTED FOR LATE
JULY. GUSTY WEST WINDS COULD GUST AS HIGH AS 30 TO 35 KNOTS IF
WE CAN MIX TO NEAR 5000 THOUSAND FEET AS SYSTEM MOVES ACROSS
CANADA. WINDS WILL GRADUALLY DECREASE LATE WEDNESDAY AFTERNOON
AND EVENING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....KURIMSKI
LONG TERM......ESB
AVIATION.......ECKBERG
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1047 AM CDT TUE JUL 28 2015
.UPDATE...
TWO AREAS OF PRECIPITATION CONTINUE TO MOVE TOWARD THE
AREA...DRIVEN MAINLY BY 700 MB WARM AIR ADVECTION AND A PASSING
500 MB VORTICITY MAXIMUM. THE FIRST BATCH HAS SHOWN SOME WEAKENING
TRENDS IN THE PAST FEW RADAR SCANS...AND SHOULD SLOWLY WEAKEN OVER
THE NEXT HOUR OR TWO.
THE SECOND AREA HAS BECOME MORE ORGANIZED INTO A CONVECTIVE LINE
OVER EASTERN IOWA IN THE PAST HOUR. THERE IS A COLD POOL BEHIND
IT...SO THIS MAY CONTINUE EAST SOUTHEAST INTO THE AFTERNOON HOURS.
HOW FAR EAST IS THE BIG QUESTION.
THE TWO HRRR MODEL VERSIONS ARE SHOWING DIFFERING
SOLUTIONS...WITH ONE TAKING IT THROUGH MOST OF THE AREA THIS
AFTERNOON...AND THE OTHER WIPING IT OUT OVER THE NEXT FEW HOURS.
FOR NOW...INCREASED POPS QUITE A BIT IN THE FAR WESTERN COUNTIES
OVER THE NEXT FEW HOURS...AS THIS AREA SHOULD SEE SOME MEASURABLE
PRECIPITATION. KEPT LOWER POPS TO THE EAST OF THERE...GIVEN SOME
UNCERTAINTY WITH HOW FAR EAST THIS PRECIPITATION WILL GET.
MEAN LAYER CAPES ARE NOT EXPECTED TO GET VERY HIGH...AND DEEP
LAYER SHEAR IS WEAK...SO NOT EXPECTING ANY SEVERE WEATHER. COULD
SEE GUSTY WINDS TO AROUND 25 KNOTS WITH THE LINE OF STORMS...IF
THEY MAKE IT INTO THE WESTERN COUNTIES. LOCALLY HEAVY RAINFALL IS
POSSIBLE GIVEN HIGH PRECIPITABLE WATER VALUES.
THE INCREASE IN CLOUDS MAY ALSO LIMIT HIGHS THIS
AFTERNOON...THOUGH MOST OF THE AREA IS ALREADY INTO THE LOWER 80S.
STILL MAY NEED TO ADJUST TEMPERATURES DOWNWARD FOR THIS AFTERNOON.
&&
.AVIATION/18Z TAFS/...
MADISON MAY SEE SOME SHOWER ACTIVITY WITH THE FIRST BATCH OF
PRECIPITATION LATER THIS MORNING...THOUGH THIS MAY DISSIPATE
BEFORE REACHING THERE. THE SECOND LINE OF SHOWERS/STORMS MAY BRING
BRIEF GUSTY WINDS TO 25 KNOTS BY EARLY THIS AFTERNOON IF IT HOLDS
TOGETHER...BUT THERE IS UNCERTAINTY IF THIS WILL MAKE IT THERE
TOO. FOR NOW...WILL MENTION RAIN SHOWERS IN TAF BUT MAY LEAVE OUT
THUNDER. MAY SEE BRIEF MVFR VISIBILITIES AND CEILINGS WITH THE
SHOWERS AND STORMS.
BROKEN TO OVERCAST MIDDLE TO HIGH CLOUDS ASSOCIATED WITH
PRECIPITATION SHOULD LINGER ACROSS THE AREA FOR MOST OF THE REST
OF TODAY. LIGHT/MODERATE SOUTH/SOUTHEAST WINDS ARE EXPECTED.
AREA OF SHOWERS AND THUNDERSTORMS ARE LIKELY WITH THE COLD FRONTAL
PASSAGE LATER TONIGHT INTO EARLY WEDNESDAY MORNING ACROSS TAF
SITES. MAY SEE MVFR VISIBILITIES AND CEILINGS AT TIMES. WILL
CONTINUE TO MENTION PREVAILING THUNDER WEST TO EAST IN TAFS LATER
TONIGHT INTO EARLY WEDNESDAY MORNING.
GUSTY WEST WINDS ARE EXPECTED WEDNESDAY BEHIND THE FRONT...WITH
GUSTS TO AROUND 20 KNOTS POSSIBLE. VFR CONDITIONS ARE EXPECTED
WEDNESDAY AT ALL SITES.
&&
.PREV DISCUSSION... /ISSUED 310 AM CDT TUE JUL 28 2015/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
CONVECTION FROM THE OVERNIGHT QLCS COMPLEX OVER THE NORTHERN PLAINS
SHOULD BE APPROACHING OUR WESTERN FORECAST AREA BY AROUND MID DAY.
THE MESO MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THAT. BUT IT WILL
BE GOING THROUGH THE TYPICAL DIURNAL DISSIPATION...SO ANTICIPATING
JUST HOW FAR EAST IT WILL GET BEFORE WIPING OUT IS CHALLENGING. THE
AIRMASS OVER SOUTHERN WISCONSIN IS QUITE DRY AND STABLE. I/LL KEEP
IT MOSTLY WEST OF MADISON. THEN WE SHOULD BE QUIET FROM MID
AFTERNOON TO EARLY EVENING. 925MB TEMPS WILL BE IN THE 23-24C
RANGE...SO ANOTHER WARM AFTERNOON WITH HIGHS IN THE MID 80S ALONG
WITH RISING DEWPOINTS. TEMPS WILL BE TRICKY WITH CLOUD COVER
SOMEWHAT UNCERTAIN GIVEN MORNING CONVECTIVE DEBRIS.
ATTENTION WILL THEN FOCUS ON THE NEXT ROUND OF STORMS FOR TONIGHT. A
COLD FRONT WILL BE APPROACHING FROM THE NORTHWEST...EVENTUALLY
REACHING MADISON TOWARD SUNRISE WEDNESDAY. THE SEVERE POTENTIAL IS
LIMITED BY A RATHER WEAK WIND FIELD THROUGH THE COLUMN AND A LATER
ARRIVAL TIME OF THE CONVECTION. MOISTURE WILL BE INCREASING RAPIDLY
LATE THIS AFTERNOON AS PRECIPITABLE WATER VALUES INCREASE BY ABOUT
AN INCH...TO JUST OVER 2 INCHES BY THIS EVENING. HOW THE CONVECTION
DEVELOPS WILL BE INFLUENCED GREATLY BY THE OUTFLOW FROM THE MORNING
CONVECTION. THUS...THERE ARE A FEW SCENARIOS AMONG THE MODELS WITH
REGARD TO TIMING/COVERAGE OF THE OVERNIGHT PRECIP. THE MID LEVELS
SHOW THE UPPER RIDGE BEING FLATTENED BY SOME SHORT WAVE ENERGY
ALREADY THIS EVENING. THIS IS AHEAD OF A MUCH LARGER UPPER LOW OVER
SOUTH CENTRAL CANADA/NCNTRL U.S. GIVEN THAT DISTANCE...THE MID LEVEL
FLOW WILL REMAIN WEAK OVER SOUTHERN WISCONSIN. IT LOOKS LIKE THE
NEXT ROUND WILL MOSTLY STAY BACK CLOSER TO THE LOW LEVEL FRONT AS
FORCING AHEAD OF IT WILL BE ON THE WEAK SIDE. JUST CAN/T RULE OUT
SOME LEADING SHOWERS/STORMS. THERE SHOULD BE A DECENT RIBBON OF HIGH
SFC DEWPOINTS RIDING JUST AHEAD OF THE SFC FRONT AS WELL. CAPE
VALUES ARE NOTHING SPECIAL...IN THE 700-1300J/KG RANGE. HOPEFULLY...WE
CAN GET SOME WIDESPREAD RAINFALL...AS CONDITIONS HAVE DRIED OUT
QUITE A BIT LATELY.
WEDNESDAY - CONFIDENCE...MEDIUM
SURFACE FRONT EXITS ERN WI VERY EARLY IN THE DAY WITH POTENTIAL
FOR SOME LINGERING SHRA. HOWEVER WARM WESTERLY FLOW WILL KICK IN
WITH 925 TEMPS IN THE 21-23C RANGE. EXPECTING A DROPOFF IN DEW
POINTS BUT NOT SO IN THE TEMP DEPT. SHOULD SEE A GOOD DEAL OF
SUNSHINE ONCE CLOUD COVER ASSOCIATED WITH FRONT EXITS ERN WI.
THURSDAY - CONFIDENCE...MEDIUM
WNW MID LEVEL FLOW CONTINUES WITH SHORTWAVE PASSING BY ACRS NRN
WI AND INTO THE U.P. NOT MUCH IN THE WAY OF FORCING HERE WITH 925
TEMPS RISING BACK UP...ESPECIALLY ON THE GFS WHERE 925 TEMPS SURGE
AS HIGH AS 26C. SO WITH THE WESTERLY LOW LEVEL FLOW CONTINUING
EXPECT TEMPS TO BE RATHER WARM...AT LEAST WELL INTO THE 80S.
FRIDAY - CONFIDENCE...MEDIUM
850 THERMAL RIDGE EXTENDS INTO SRN WI WITH SURFACE/850 TROUGH
PROGGD TO SWING THROUGH. GFS SHOWS SPOTTY PRECIP THOUGH NOT MUCH
UPPER SUPPORT TO LATCH ONTO. SPOTTY PRECIP ON GFS IS SOUTH OF THE
AREA AND 00Z ECMWF HAS COME IN DRIER THAN THE 12Z RUN. PER COLLAB
WITH KLOT HAVE ELECTED TO REMOVE THE SMALL SUPERBLEND POPS THAT
WERE SHOWN FOR THE ERN CWA.
SATURDAY - CONFIDENCE...MEDIUM
SURFACE RIDGE AXIS SLIDES ACROSS AND TO THE SOUTH OF WI THIS
PERIOD. PRECIP CHANCES ARE LOOKING TO REMAIN TO OUR WEST WITH THE
NEXT APPROACHING TROUGH. 925 TEMPS ARE PROGGD TO STILL BE IN THE
LOWER 20S CELSIUS SO MORE 80S IN THE WORKS.
SATURDAY NIGHT THROUGH MONDAY - CONFIDENCE...MEDIUM
APPEARS THERE MAY BE A COUPLE OF DIFFERENT FRONTAL BOUNDARIES
THAT GENERATE PRECIP THIS PERIOD WITH STRONG WNW UPPER FLOW
PERSISTING.
AVIATION/12Z TAFS/...OVERNIGHT CONVECTION IN THE NORTHERN PLAINS
WILL BE APPROACHING WESTERN WISCONSIN BY LATE MORNING...BUT SHOULD
DISSIPATE BEFORE REACHING KMSN. THEREFORE LOOK FOR QUIET...VFR
CONDITIONS THROUGH ABOUT MID EVENING. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS IS EXPECTED ACROSS THE AREA TONIGHT ALONG AND AHEAD
OF AN APPROACHING COLD FRONT. THE BEST CHANCE FOR STORMS AT KMSN
WILL BE LATE THIS EVENING OR AROUND MIDNIGHT AND A FEW HOURS LATER
AT KMKE/KUES/KENW. THE STORMS SHOULD WE WEAKENING IN INTENSITY AND
COVERAGE BY THE TIME THEY REACH EASTERN WISCONSIN LATER TONIGHT.
MVFR CONDITIONS ARE POSSIBLE AS THE SHOWERS AND STORMS MOVE
THROUGH.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...WOOD
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
WEDNESDAY THROUGH MONDAY...COLLAR
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
949 PM PDT WED JUL 29 2015
.SYNOPSIS...
MONSOONAL MOISTURE AROUND STRONG HIGH PRESSURE OVER THE FOUR CORNERS
REGION WILL BRING WARM...HUMID WEATHER INTO THE REGION THROUGH
THURSDAY. SCATTERED SHOWERS AND THUNDERSTORMS ARE LIKELY OVER THE
MOUNTAINS AND DESERTS. SOME STORMS MAY DRIFT INTO THE INLAND VALLEYS
TONIGHT AND THURSDAY...AND POSSIBLY TO THE COAST AT TIMES. THE
AIRMASS DRIES OUT OVER THE WEEKEND INTO EARLY NEXT WEEK FOR LOWER
CHANCES FOR AFTERNOON THUNDERSTORMS OVER THE MOUNTAINS AND DESERTS.
THE MARINE LAYER WILL REMAIN MAINLY OVER THE COAST AND PORTIONS OF
THE VALLEYS.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
RADAR THIS EVENING SHOWS THAT THUNDERSTORM ACTIVITY HAS DIMINISHED
SUBSTANTIALLY OVER THE FORECAST AREA. HOWEVER...NOCTURNAL
THUNDERSTORM AND SHOWER ACTIVITY LOOKS POSSIBLE LATE TONIGHT THROUGH
THURSDAY MORNING AS AN EASTERLY WAVE MOVES OVER THE REGION. WITH THE
WAVE WILL ALSO BE A SECOND AND MORE SIGNIFICANT SURGE OF MOISTURE
INTO THE AREA...WITH NAM12 SHOWING PRECIPITABLE WATER INCREASING TO
2 INCHES. THE NAM12 AND GFS40 SHOW THIS WAVE WELL...AND THE GFS40
CONTINUES TO PAINT A LARGE AREA OF LIGHT PRECIPITATION OVER SOUTHERN
CALIFORNIA IN ASSOCIATION WITH THE WAVE. THE HRRR HAS BEEN FLIP-
FLOPPING WITH EACH RUN WITH HOW MUCH ACTIVITY OCCURS WITH THIS
WAVE...WITH SOME RUNS SHOWING SOME LIGHT SHOWERS MOVING THROUGH THE
REGION...AND OTHER RUNS SHOWING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ALL THE WAY TO THE COAST. HOWEVER...THERE IS A GOOD
AMOUNT OF ELEVATED INSTABILITY FROM THE COAST THROUGH THE DESERTS
INDICATED BY THE WRF AND GFS BUFKIT FORECAST SOUNDINGS FOR TONIGHT
INTO TOMORROW...SO IF THE VORT MAX ASSOCIATED WITH THE WAVE IS ABLE
TO TRIGGER ACTIVITY...IT SHOULD RESULT IN A FAIR AMOUNT OF LIGHTNING
AS WELL. THE STORMS SHOULD BE MOVING SOMEWHAT QUICKLY...AS THE 700-
500 MB FLOW IS FORECAST TO BE 15-30 KT OUT OF THE EAST.
THE WAVE LOOKS TO MOVE OFF TO THE WEST BY LATE THURSDAY
MORNING...AND THE CLEARER SKIES BEHIND IT SHOULD RESULT IN GOOD DAY-
TIME HEATING AND INSTABILITY FOR MOUNTAIN AND DESERT THUNDERSTORMS
TO DEVELOP. THE INLAND EMPIRE SHOULD HAVE A GOOD CHANCE OF SEEING
STORMS AS WELL...AS THE WRF SHOWS THE ELSINORE CONVERGENCE BOUNDARY
SETTING UP BY MID-AFTERNOON. THE 700-500 MB FLOW WILL BE A LITTLE
LIGHTER...BUT STILL 15-20 KT OUT OF THE SOUTHEAST...SO STORMS MAY
STILL MOVE AT A DECENT PACE. HOWEVER...WITH HOW HIGH THE MOISTURE
AND INSTABILITY WILL BE...EVEN BRIEF HEAVY RAINFALL MAY BE ENOUGH TO
PRODUCE FLASH FLOODING...ESPECIALLY OVER RECENT BURN SCARS. A FLASH
FLOOD WATCH GOES INTO EFFECT EARLY THURSDAY MORNING AND CONTINUES
THROUGH EARLY THURSDAY EVENING FOR THE MOUNTAINS...DESERTS AND
INLAND EMPIRE. SOME STORMS COULD MAKE IT ALL THE WAY TO THE COAST AS
WELL...ALTHOUGH THE BETTER CHANCES FOR THAT WILL BE WITH THE
AFOREMENTIONED EASTERLY WAVE MOVING THROUGH LATE TONIGHT INTO
THURSDAY MORNING.
THE REST OF THE FORECAST REMAINS ON TRACK.
THE LAST PART OF THE PREVIOUS DISCUSSION ISSUED AT 145 PM FOLLOWS...
ON THURSDAY NIGHT AND FRIDAY THE UPPER LEVEL WINDS SHIFT FROM THE
SOUTHEAST TO THE SOUTH AND MOST OF THE THUNDERSTORM ACTIVITY WILL BE
CONFINED TO THE MOUNTAINS AND DESERTS. OVER THE WEEKEND THE AIRMASS
DRIES OUT WITH PRECIPITABLE WATER LOWERING TO LESS THAN 1.00". THIS
WILL LOWER THE THUNDERSTORM THREAT OVER THE MOUNTAINS AND DESERTS
SATURDAY AND SUNDAY.
THE LONG RANGE PROGS KEEP THE SUBTROPICAL HIGH OVER THE SOUTHWEST
AND BRING IN A SMALL SURGE OF MONSOON MOISTURE BACK INTO SOUTHERN
CALIFORNIA FOR CONTINUED CHANCES OF AFTERNOON THUNDERSTORMS OVER THE
MTNS. LATE NEXT WEEK THE UPPER HIGH WILL BE SUPPRESSED SOUTHWARD BY
A TROUGH DEEPENING ALONG THE NORTHERN CALIFORNIA COAST. DRIER
SOUTHWEST FLOW WILL CURTAIL THUNDERSTORM DEVELOPMENT AS THE DEEPEST
MONSOON MOISTURE WILL BE FORCED SOUTH AND EAST OF OUR AREA.
MARINE LAYER CLOUDS CLUNG TO THE BEACHES THIS AFTERNOON AND A
SIMILAR OCCURRENCE IS POSSIBLE THURSDAY. A STRONG INVERSION WILL
REMAIN IN PLACE THROUGH FRIDAY WHICH MAY KEEP LOW CLOUDS AT THE
BEACHES INTO THE AFTERNOON.
&&
.AVIATION...
300315Z...COAST/VALLEYS...SCT CLOUDS ACROSS THE AREA FROM REMNANT
THUNDERSTORMS IN THE MOUNTAINS AND SOME REMNANT MARINE STRATUS ALONG
THE COAST WILL CONTINUE OVERNIGHT. THE BIGGER QUESTION IS WILL
NOCTURNAL THUNDERSTORMS OCCUR WITH THE WEAK UPPER LEVEL DISTURBANCE
OVER SOUTHEAST CA AND W AZ MOVING OVERHEAD? MODELS ARE LOOKING GOOD
FOR SOME DEVELOPMENT...BUT ONE RIGHT OVER A TERMINAL SITE IS THE
DIFFICULT QUESTION. IT IS LIKELY FLIGHT PATTERNS WILL NOTE SOME
CONVECTION SO VICINITY THUNDER IS IN THE FORECAST WITH GREATEST
CHANCES AFTER 300700Z TO AROUND 310200Z. MOST OF THIS WILL BE HIGH
BASES AT OR ABOVE 8000 FT MSL AND MOST OF THE AFTERNOON THUNDERSTORM
RISK...301900-310200Z... WILL BE MORE IN THE MOUNTAINS AND DESERT
WITH JUST REMNANT CLOUD ELEMENTS DRIFTING OVER THE AIRPORTS.
MTNS/DESERTS...THE SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
CONTINUE THROUGH THE NIGHT UNTIL AROUND 301500Z. A BRIEF BREAK MAY
OCCUR BEFORE THINGS START REGENERATING WITH THE HEAT OF THE DAY FROM
301900-310200Z. THERE IS A RISK OF CB WITH TOPS TO 40000 FT MSL
OVERNIGHT AND AGAIN IN THE AFTERNOON AND EVENING ON THURSDAY. BASES
WILL GENERALLY BE AT OR ABOVE 8000 FT MSL EXCEPT LOWERING NEAR
THUNDERSTORMS.
&&
.MARINE...
8 PM...THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS OVER
THE NEARBY COASTAL WATERS AND ESTUARIES OVERNIGHT THROUGH THURSDAY
AFTERNOON AS AN UPPER LEVEL DISTURBANCE MOVES OVER THE AREA.
OTHERWISE...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH SUNDAY.
&&
.BEACHES...
8 PM...ELEVATED SURF ON WEDNESDAY CAUSED A FEW PROBLEMS INCLUDING
STRONG RIP CURRENTS AT THE BEACHES OF SAN DIEGO COUNTY AND SOUTHERN
ORANGE COUNTY. THE SURF IS SUBSIDING THURSDAY...BUT THE RISK OF
LIGHTNING INCREASES OVERNIGHT THROUGH THURSDAY. LARGE RIP CURRENTS
ARE POSSIBLE AND LIGHTNING...THEREFORE THE BEACH HAZARD STATEMENT
WILL CONTINUE THROUGH THURSDAY EVENING. SURF CONDITIONS WILL IMPROVE
SLIGHTLY DURING THE DAY THURSDAY AS THE WELL DECLINES TO AROUND 2 FT
AT 14-15 SEC...BUT THE RIP CURRENT RISK WILL REMAIN HIGH. THE SLOW
DOWNWARD TREND IN THE SWELL WILL CONTINUE FOR FRIDAY THROUGH THE
WEEKEND. AGAIN...THE THUNDERSTORM POTENTIAL AND DANGEROUS CLOUD TO
BEACH/WATER LIGHTNING IS THERE OVERNIGHT TONIGHT INTO THURSDAY
EVENING.
&&
.SKYWARN...
SKYWARN ACTIVATION MAY BE REQUESTED ON THURSDAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...FLASH FLOOD WATCH FROM 3 AM PDT THURSDAY THROUGH THURSDAY
EVENING FOR APPLE AND LUCERNE VALLEYS-COACHELLA VALLEY-
RIVERSIDE COUNTY MOUNTAINS-SAN BERNARDINO COUNTY MOUNTAINS-
SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND
EMPIRE-SAN DIEGO COUNTY DESERTS-SAN DIEGO COUNTY MOUNTAINS-
SAN GORGONIO PASS NEAR BANNING.
BEACH HAZARDS STATEMENT THROUGH THURSDAY EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...NONE.
&&
$$
PUBLIC...HARRISON
AVIATION/MARINE/BEACHES...PIERCE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
346 AM MDT THU JUL 30 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 345 AM MDT THU JUL 30 2015
BROAD HIGH PRESSURE ALOFT CONTINUES ACROSS THE SOUTHERN TIER
STATES...WITH SOME BUILDING OF THE HIGH FURTHER WEST AND NORTH ACROSS
THE GREAT BASIN. THIS WILL KEEP SOME DRIER...WESTERLY FLOW ACROSS
NORTHERN COLORADO...WHILE SOUTHERN COLORADO REMAINS UNDER A
WETTER...SOUTHWEST FLOW. HIGHER POPS TODAY AGAIN WILL REMAIN OVER
SOUTHERN PORTIONS OF CWA...ESPECIALLY OVER PARK COUNTY AND
EXTENDING FURTHER EAST ACROSS THE PALMER DIVIDE. SURFACE TROF OVER
EASTERN COLORADO BECOMES ELONGATED ACROSS NORTHEAST COLORADO WHICH
RESULTS IN SOME WEAK CONVERGENCE FROM THE PALMER DIVIDE AND
STRETCHES THROUGH FAR NE PLAINS. IN ADDITION...JET STREAK ACROSS
THE MIDWEST MAY PRODUCE SOME WEAK LIFT OVER THE PLAINS AS WELL.
INDEED...THE RAP DOES SOME HAVE SOME WEAK LIFT IN THE 700MB QG
VERTICAL VELOCITY FIELD.
TEMPERATURES TODAY WILL BE A FEW DEGREES HIGHER TODAY OVER
NORTHERN SECTIONS WITH THE DRIER AND SLIGHTLY WARMER AIRMASS. MAIN
CHANGE WAS TO EXTEND POPS A BIT FURTHER NORTH ON THE FAR PLAINS
THROUGH THIS EVENING.
SATELLITE IMAGERY THIS MORNING SHOWING SOME STRATUS AND POTENTIAL
FOG DEVELOPING OVER LINCOLN COUNTY AND WILL TO TO GRIDS TO COVER
THIS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT THU JUL 30 2015
MODELS ARE STILL IN AGREEMENT AS THEY CONTINUE TO EXTEND THE
UPPER RIDGE NORTHWESTWARD ACROSS THE NORTHERN GREAT BASIN PLACING
NERN COLORADO UNDER A SOMEWHAT DRIER NWLY MID-LEVEL FLOW FRIDAY
MORNING. MEANWHILE SUBTROPICAL MOISTURE POOLING ACROSS NORTHERN
NEW MEXICO/NERN ARIZONA IS FORECAST TO FLOW NORTHWARD INTO SRN
COLORADO EARLY IN THE DAY AND UP ALONG THE NORTHERN FRONT RANGE
DURING THE AFTERNOON. DAYTIME HEATING COUPLED WITH THE INCREASE
IN PRECIPITABLE WATER SHOULD MANAGE TO PRODUCE SCATTERED T-STORMS
OVER THE FRONT RANGE MTNS DURING THE AFTERNOON AND POSSIBLY AS
EARLY AS LATE MORNING OVER THE MOSQUITO RANGE AND SOUTH PARK IN
PARK COUNTY. NWLY TRANSPORT WINDS SHOULD THEN MOVE THESE STORMS
OVER THE ADJACENT HIGH PLAINS DURING THE MID AND LATE AFTERNOON
HRS WHERE THEY SHOULD LINGER THRU MID-EVENING PRODUCING GUSTY
WINDS AND BRIEF LIGHT TO MODERATE RAINFALL. PRECIP CHANCES IN THE
30-40 PCT RANGE IN THE HIGH COUNTRY AND 10-20 PCT AT LOWER
ELEVATIONS. THE PRESENCE OF A STRONG MID-LEVEL CAP SHOULD HINDER
THE FORMATION OF DEEP UPDRAFTS AND THEREFORE STORMS SHOULD STAY
WELL BELOW SEVERE CRITERIA. HIGHS ON FRIDAY STILL BELOW AVERAGE
WITH MID/UPPER 80S WITH MAINLY 70S IN THE HIGH COUNTRY.
LOOKING AHEAD TO THE WEEKEND...THE NEGATIVELY TILTED UPPER RIDGE
OVER THE WESTERN CONUS CONTINUES TO BUILD NORTHWARD ON SATURDAY
WHICH PUSHES THE SUBTROPICAL MOISTURE PLUME SOUTHWARD RESULTING IN
DRIER AND WARMER CONDITIONS FOR THE CWA. THEREFORE SHOULD SEE LESS
STORM ACTIVITY ON SATURDAY...WITH THE BEST CHANCE FOR STORMS OVER
THE HIGHER TERRAIN SOUTH OF INTERSTATE 70. ON SUNDAY...THE UPPER
RIDGE SHIFTS EAST WITH LIGHT W-NWLY FLOW MOVING OVER THE FCST AREA.
SUBTROPICAL MOISTURE TRAPPED BENEATH THE RIDGE REVERSES ITS COURSE
AND BEGINS FLOWING NORTHWARD ACRS COLORADO. SHOULD SEE A FEW MORE T-
STORMS IN THE HIGH COUNTRY WITH ONLY A SLIGHT CHANCE ON THE NEARBY
PLAINS. HIGHS ON SUNDAY CREEP UP TO NEAR ABOVE AVERAGE.
MONDAY THROUGH WEDNESDAY...THE UPPER RIDGE IS STILL PROGGED TO
REMAIN OVER THE ROCKY MTN REGION WITH LITTLE DAY-TO-DAY CHANGE IN
WEATHER. ALTHOUGH THE ECMWF SHOWS A RATHER VIGOROUS SHORTWAVE
ROTATING ACROSS THE STATE ON MONDAY. THIS IS NEW IN THE MODEL. SO
WILL NOT BASE TOO MUCH OF THE FCST ON THIS FEATURE AT THE PRESENT
TIME. EXPECT TEMPERATURES TO RANGE FROM NEAR TO SLIGHTLY ABOVE
AVERAGE DURING THE PERIOD...WITH A CHANCE OF AFTERNOON AND EVENING T-
STORMS MAINLY IN AND NEAR THE MTNS EACH DAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 345 AM MDT THU JUL 30 2015
SURFACE WINDS BEGINNING TO TURN MORE SOUTHWEST AND WEST AT DEN/BJC
AS SURFACE LOW BEGINS TO PUSH EAST. WIND FIELDS EXPECTED MORE WEST
AND NORTHWEST THIS AM BEFORE TURNING LIGHT NORTHEAST THIS
AFTERNOON. MUCH OF THE STORMS TODAY WILL BE SOUTH OF TERMINALS BUT
WEAK CONVERGENCE MAY HELP SPARK AN ISOLATED STORM FROM APA TO BKF
VICINITY. CONVERGENCE AT THIS POINT LOOKS LOW ENOUGH STILL NOT TO
MENTION IN TERMINAL FORECASTS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS NEW YORK NY
221 AM EDT THU JUL 30 2015
.SYNOPSIS...
WEAK HIGH PRESSURE WILL SLIDE OFF THE MID ATLANTIC COAST TONIGHT.
A COLD FRONT WILL APPROACH ON THURSDAY...AND MOVE ACROSS THURSDAY
NIGHT. WEAK HIGH PRESSURE WILL RETURN FRIDAY THROUGH SATURDAY. A
WEAK LOW PRESSURE TROUGH WILL MOVE THROUGH SATURDAY NIGHT INTO
EARLY SUNDAY...FOLLOWED BY ANOTHER WEAK TROUGH SUNDAY NIGHT. A
COLD FRONT WILL APPROACH MONDAY NIGHT...AND REMAIN NEARBY THROUGH
MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FORECAST OVERNIGHT REMAINS ON TRACK. UPDATED THE NEAR TERM GRIDS
TO BETTER REFLECT TRENDS IN LATEST OBSERVATIONS AND MODEL DATA
MAINLY WITH RESPECT TO TEMPERATURES AND DEWPOINTS. ADDED IN SOME
PATCHY FOG TOWARDS DAYBREAK ACROSS EASTERN SECTIONS WHERE LOWER
TEMP AND DEWPOINT DEPRESSIONS RESIDE.
A LARGE CONSENSUS OF BOTH SYNOPTIC AND MESOSCALE MODELS POINTING
TOWARDS SOME CONVECTIVE DEVELOPMENT NEAR AND WEST OF NYC AFTER
08Z. POPS WERE LEFT AS PREVIOUSLY FORECAST.
WARM AND MUGGY TONIGHT WITH LOWS IN THE 70S FOR MUCH OF THE
AREA ALTHOUGH A FEW SPOTS IN THE NYC METRO MAY STRUGGLE TO FALL
BELOW 80 DEGREES.
CONVECTION IN PARTS OF THE MID ATLANTIC AND CENTRAL
APPALACHIANS ASSOCIATED WITH AN APPROACHING SHORTWAVE HAS
LARGELY DISSIPATED OVER THE LAST FEW HOURS. NOT EXPECTING MUCH IN
THE WAY OF CONVECTIVE ACTIVITY WITH THIS SHORTWAVE...BUT AN ISO
SHOWER OR STORM CANNOT BE RULED OUT BEFORE DAYBREAK. THE LAST
SEVERAL RUNS OF THE HRRR HINT AT THIS POSSIBILITY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
COULD STILL SEE ISO TO WDLY SCT ELEVATED CONVECTION FROM NYC
METRO NORTH/WEST IN THE MORNING AS THE LEADING SHORTWAVE MOVES
THROUGH. APPROACHING COLD FRONT SHOULD BRING SCT TO NUMEROUS TSTMS
FROM LATE AFTERNOON INTO THE EVENING AS AIR MASS
DESTABILIZES...WITH SBCAPE UP TO 1000 J/KG. THERE SHOULD BE ENOUGH
SHEAR TO SUPPORT AN ORGANIZED LINE OF STORMS OR MULTI-CELL
CLUSTERS...AND GIVEN A SW LLJ UP TO 35 KT AS FCST PER NAM...THESE
STORMS HAVE A BETTER CHANCE OF SURVIVING AS THEY MOVE PAST NYC
METRO AND THE LOWER HUDSON VALLEY INTO LONG ISLAND AND CT.
STRONGER CELLS HAVE POTENTIAL TO PRODUCE STRONG WIND GUSTS AND
DUMP LOCALLY HEAVY RAINFALL AS PW INCREASES TO JUST OVER 2 INCHES.
HIGHS ON THURSDAY SHOULD BE NOT QUITE AS WARM AS TODAY...GENERALLY
85-90...BUT WITH HIGHER DEWPOINTS MAX HEAT INDEX VALUES SHOULD
STILL BE SIMILAR TO THOSE OF TODAY...STILL REACHING THE MID 90S
EXCEPT IN THE HIGHER ELEVATIONS AND EASTERN COASTAL SECTIONS...SO
THE HEAT ADVY WILL CONTINUE FOR NYC.
THERE IS A HIGH RISK OF RIP CURRENTS AT OCEAN BEACHES ON
THURSDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
LONG WAVE UPPER LEVEL TROUGH WILL BE OVER THE NORTHEAST U.S. FOR
MUCH OF THIS TIME PERIOD. AT THE SURFACE...A COLD FRONT WILL REMAIN
JUST OFF THE EAST COAST FRIDAY...WITH WEAK HIGH PRESSURE BUILDING
IN. SUBSIDENCE FROM THIS HIGH SHOULD KEEP THE AREA DRY THROUGH MUCH
OF SATURDAY. A WEAK SURFACE TROUGH APPROACHES LATE
SATURDAY...WEAKENING AS IT DOES SO. 12Z GFS DOES SEEM MORE POTENT AS
OPPOSED TO THE 00Z ECMWF AND BRINGS THE TROUGH THROUGH LATE SATURDAY
NIGHT WITH A BRIEF PERIOD OF SHOWERS AND THUNDERSTORMS. SOME
INSTABILITY PRECEDING THE TROUGH...SO THUNDERSTORMS ARE POSSIBLE.
HOWEVER...JET DYNAMICS LOOK WEAK...THOUGH LIFT WITH THE TROUGH AT
LEAST EARLY IN THE NIGHT LOOKS DECENT ACCORDING TO THE 12Z GFS.
HOWEVER...LIFT QUICKLY WEAKENS AS THE TROUGH MOVES EAST LATE
SATURDAY NIGHT.
WEAK HIGH PRESSURE BUILDS IN FOR SUNDAY AND MONDAY WITH A COLD FRONT
APPROACHING MONDAY NIGHT. COLD FRONT SLOWS ITS APPROACH AND BECOMES
NEARLY STATIONARY IN THE VICINITY MONDAY NIGHT INTO WEDNESDAY.
AGAIN...SOME INSTABILITY OVER THE AREA AS THE FRONT MOVES
THROUGH...MAINLY FOR EASTERN SECTIONS...SO THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE. LIFTED INDICES -8 TO -2 DURING TUESDAY NIGHT...WITH
LIFT BEING PROVIDED BY THE FRONT. MOISTURE IS ALSO AVAILABLE...WITH
SURFACE DEWPOINTS IN THE 60S AND PW RANGING FROM 1.25-1.50...THOUGH
THEY ARE NOT EXCEPTIONALLY HIGH.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
A SOUTHERLY FLOW CONTINUES AROUND HIGH PRESSURE OFF THE MID
ATLANTIC COAST AS A COLD FRONT THROUGH THE GREAT LAKES AND INTO
OHIO SLOWLY APPROACHES.
GENERALLY VFR THROUGH THE MORNING...ALTHOUGH ISOLD MVFR IN
FOG/HAZE DEVELOPING. SEVERAL PIECES OF GUIDANCE INDICATING WDLY
SCT SHOWER ACTIVITY DEVELOPING OVER CENTRAL/NRN NJ BETWEEN 09Z AND
12Z AND TRACKING TO THE NE THROUGH 15Z OR SO. HAVE INCLUDED VCSH
AT MOST TERMINALS TO ACCOUNT FOR THIS...BUT WOULD LIKE TO SEE
SOMETHING ON RADAR BEFORE ADDING IT INTO PREVAILING OR TEMPO.
THE COLD FRONT AND A WEAK PRE-FRONTAL TROUGH WILL BE MOVING INTO
THE TERMINALS AROUND 18Z TODAY AND MOVE THROUGH THIS EVENING.
SCATTERED SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE FRONT WITH
MVFR CONDITIONS...OR POSSIBLY IFR IN STRONGER STORMS. THERE IS A
HIGHER CHANCE OF CONVECTION FROM THE NYC TERMINALS AND AREAS WEST.
WILL CONTINUE TO INDICATE THE CHANCES WITH A PROB GROUP.
HEAVY RAIN WILL LIKELY ACCOMPANY ANY SHOWERS THIS MORNING AND
ESPECIALLY IN TSTMS THIS AFTN/EVE. THIS WILL DROP VSBYS TO IFR OR
LOWER IN THE HEAVIEST ACTIVITY.
MODERATE TO HIGH CONFIDENCE IN WIND FORECAST...GUSTS IN THE UPPER
TEENS TO LOWER 20S POSSIBLE AT KJFK AS WELL AS OTHER COASTAL
TERMINALS.
.OUTLOOK FOR 06Z FRIDAY THROUGH MONDAY...
.THURSDAY NIGHT...MVFR CONDS IN FOG/HZ BECOMING VFR.
.FRIDAY-MONDAY...VFR.
&&
.MARINE...
QUIET THROUGH THU MORNING. THEN AS SW FLOW INCREASES TO 15-20 KT
WITH FAVORABLE FETCH...OCEAN SEAS SHOULD BUILD TO 5-6 FT THU
AFTERNOON AND NIGHT. LOW LEVEL JET PASSING OHD SHOULD MIX TO THE
SFC...WITH GUSTS UP TO 25 KT LIKELY ON THE OCEAN AND THE BAYS OF
LONG ISLAND. SCA ISSUED FOR THESE HAZARDS. TSTMS WILL ALSO BE A
HAZARD WITH A COLD FRONTAL PASSAGE THU AFTERNOON/EVENING.
OCEAN SEAS COULD BUILD TO AROUND 5 FT SAT NIGHT INTO SUNDAY...
AND AGAIN LATE SUNDAY INTO MONDAY MORNING. THEN A MORE PROLONGED
PERIOD OF 5-FT OCEAN SEAS IS POSSIBLE FROM MON NIGHT INTO MID
WEEK.
&&
.HYDROLOGY...
BASIN AVG QPF OF 1/2 TO 3/4 INCH POSSIBLE IN THE LOWER HUDSON
VALLEY AND NE NJ...WITH UP TO 1/2 INCH ELSEWHERE. WITH PW OVER 2
INCHES THU AFTERNOON AND EVENING...LOCALLY HEAVY RAINFALL IS
POSSIBLE WITH ANY STRONGER CONVECTION. MINOR URBAN/POOR DRAINAGE
FLOODING IS THE MOST LIKELY OUTCOME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NYZ072>075-176-
178.
HIGH RIP CURRENT RISK FROM 6 AM EDT THIS MORNING THROUGH THIS
EVENING FOR NYZ075-080-081-178-179.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS
EVENING FOR ANZ340-345.
SMALL CRAFT ADVISORY FROM NOON TODAY TO MIDNIGHT EDT TONIGHT
FOR ANZ355.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM EDT FRIDAY FOR
ANZ350-353.
&&
$$
SYNOPSIS...GOODMAN/JP
NEAR TERM...GOODMAN/JM/DS
SHORT TERM...GOODMAN/DS
LONG TERM...JP
AVIATION...24
MARINE...GOODMAN/JP
HYDROLOGY...GOODMAN/JP
AREA FORECAST DISCUSSION
NWS NEW YORK NY
119 AM EDT THU JUL 30 2015
.SYNOPSIS...
WEAK HIGH PRESSURE WILL SLIDE OFF THE MID ATLANTIC COAST TONIGHT.
A COLD FRONT WILL APPROACH ON THURSDAY...AND MOVE ACROSS THURSDAY
NIGHT. WEAK HIGH PRESSURE WILL RETURN FRIDAY THROUGH SATURDAY. A
WEAK LOW PRESSURE TROUGH WILL MOVE THROUGH SATURDAY NIGHT INTO
EARLY SUNDAY...FOLLOWED BY ANOTHER WEAK TROUGH SUNDAY NIGHT. A
COLD FRONT WILL APPROACH MONDAY NIGHT...AND REMAIN NEARBY THROUGH
MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FORECAST OVERNIGHT REMAINS ON TRACK. UPDATED THE NEAR TERM GRIDS
TO BETTER REFLECT TRENDS IN LATEST OBSERVATIONS AND MODEL DATA
MAINLY WITH RESPECT TO TEMPERATURES AND DEWPOINTS. ADDED IN SOME
PATCHY FOG TOWARDS DAYBREAK ACROSS EASTERN SECTIONS WHERE LOWER
TEMP AND DEWPOINT DEPRESSIONS RESIDE.
A LARGE CONSENSUS OF BOTH SYNOPTIC AND MESOSCALE MODELS POINTING
TOWARDS SOME CONVECTIVE DEVELOPMENT NEAR AND WEST OF NYC AFTER
08Z. POPS WERE LEFT AS PREVIOUSLY FORECAST.
WARM AND MUGGY TONIGHT WITH LOWS IN THE 70S FOR MUCH OF THE
AREA ALTHOUGH A FEW SPOTS IN THE NYC METRO MAY STRUGGLE TO FALL
BELOW 80 DEGREES.
CONVECTION IN PARTS OF THE MID ATLANTIC AND CENTRAL
APPALACHIANS ASSOCIATED WITH AN APPROACHING SHORTWAVE HAS
LARGELY DISSIPATED OVER THE LAST FEW HOURS. NOT EXPECTING MUCH IN
THE WAY OF CONVECTIVE ACTIVITY WITH THIS SHORTWAVE...BUT AN ISO
SHOWER OR STORM CANNOT BE RULED OUT BEFORE DAYBREAK. THE LAST
SEVERAL RUNS OF THE HRRR HINT AT THIS POSSIBILITY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
COULD STILL SEE ISO TO WDLY SCT ELEVATED CONVECTION FROM NYC
METRO NORTH/WEST IN THE MORNING AS THE LEADING SHORTWAVE MOVES
THROUGH. APPROACHING COLD FRONT SHOULD BRING SCT TO NUMEROUS TSTMS
FROM LATE AFTERNOON INTO THE EVENING AS AIR MASS
DESTABILIZES...WITH SBCAPE UP TO 1000 J/KG. THERE SHOULD BE ENOUGH
SHEAR TO SUPPORT AN ORGANIZED LINE OF STORMS OR MULTI-CELL
CLUSTERS...AND GIVEN A SW LLJ UP TO 35 KT AS FCST PER NAM...THESE
STORMS HAVE A BETTER CHANCE OF SURVIVING AS THEY MOVE PAST NYC
METRO AND THE LOWER HUDSON VALLEY INTO LONG ISLAND AND CT.
STRONGER CELLS HAVE POTENTIAL TO PRODUCE STRONG WIND GUSTS AND
DUMP LOCALLY HEAVY RAINFALL AS PW INCREASES TO JUST OVER 2 INCHES.
HIGHS ON THURSDAY SHOULD BE NOT QUITE AS WARM AS TODAY...GENERALLY
85-90...BUT WITH HIGHER DEWPOINTS MAX HEAT INDEX VALUES SHOULD
STILL BE SIMILAR TO THOSE OF TODAY...STILL REACHING THE MID 90S
EXCEPT IN THE HIGHER ELEVATIONS AND EASTERN COASTAL SECTIONS...SO
THE HEAT ADVY WILL CONTINUE FOR NYC.
THERE IS A HIGH RISK OF RIP CURRENTS AT OCEAN BEACHES ON
THURSDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
LONG WAVE UPPER LEVEL TROUGH WILL BE OVER THE NORTHEAST U.S. FOR
MUCH OF THIS TIME PERIOD. AT THE SURFACE...A COLD FRONT WILL REMAIN
JUST OFF THE EAST COAST FRIDAY...WITH WEAK HIGH PRESSURE BUILDING
IN. SUBSIDENCE FROM THIS HIGH SHOULD KEEP THE AREA DRY THROUGH MUCH
OF SATURDAY. A WEAK SURFACE TROUGH APPROACHES LATE
SATURDAY...WEAKENING AS IT DOES SO. 12Z GFS DOES SEEM MORE POTENT AS
OPPOSED TO THE 00Z ECMWF AND BRINGS THE TROUGH THROUGH LATE SATURDAY
NIGHT WITH A BRIEF PERIOD OF SHOWERS AND THUNDERSTORMS. SOME
INSTABILITY PRECEDING THE TROUGH...SO THUNDERSTORMS ARE POSSIBLE.
HOWEVER...JET DYNAMICS LOOK WEAK...THOUGH LIFT WITH THE TROUGH AT
LEAST EARLY IN THE NIGHT LOOKS DECENT ACCORDING TO THE 12Z GFS.
HOWEVER...LIFT QUICKLY WEAKENS AS THE TROUGH MOVES EAST LATE
SATURDAY NIGHT.
WEAK HIGH PRESSURE BUILDS IN FOR SUNDAY AND MONDAY WITH A COLD FRONT
APPROACHING MONDAY NIGHT. COLD FRONT SLOWS ITS APPROACH AND BECOMES
NEARLY STATIONARY IN THE VICINITY MONDAY NIGHT INTO WEDNESDAY.
AGAIN...SOME INSTABILITY OVER THE AREA AS THE FRONT MOVES
THROUGH...MAINLY FOR EASTERN SECTIONS...SO THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE. LIFTED INDICES -8 TO -2 DURING TUESDAY NIGHT...WITH
LIFT BEING PROVIDED BY THE FRONT. MOISTURE IS ALSO AVAILABLE...WITH
SURFACE DEWPOINTS IN THE 60S AND PW RANGING FROM 1.25-1.50...THOUGH
THEY ARE NOT EXCEPTIONALLY HIGH.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
A SOUTHERLY FLOW CONTINUES AROUND HIGH PRESSURE OFF THE MID
ATLANTIC COAST AS A COLD FRONT THROUGH THE GREAT LAKES AND INTO
OHIO SLOWLY APPROACHES. THE COLD FRONT AND A WEAK PRE FRONTAL TROUGH
WILL BE MOVING INTO THE TERMINALS AROUND 18Z THURSDAY AND MOVE
THROUGH THURSDAY EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL
ACCOMPANY THE FRONT WITH MVFR CONDITIONS...OR POSSIBLY IFR IN
STRONGER STORMS. THERE IS A HIGHER CHANCE OF CONVECTION FROM THE NYC
TERMINALS AND AREAS WEST. WILL CONTINUE TO INDICATE THE CHANCES WITH
A PROB GROUP.
OTHERWISE VFR UNTIL TOWARD MORNING WHEN MVFR VISIBILITIES WILL BE
POSSIBLE IN FOG AND/OR HAZE.
.OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
.THURSDAY NIGHT...SCATTERED SHOWERS AND THUNDERSTORMS ENDING IN THE
EVENING WITH MVFR CONDITIONS POSSIBLE...THEN BECOMING VFR.
.FRIDAY-MONDAY...VFR.
&&
.MARINE...
QUIET THROUGH THU MORNING. THEN AS SW FLOW INCREASES TO 15-20 KT
WITH FAVORABLE FETCH...OCEAN SEAS SHOULD BUILD TO 5-6 FT THU
AFTERNOON AND NIGHT. LOW LEVEL JET PASSING OHD SHOULD MIX TO THE
SFC...WITH GUSTS UP TO 25 KT LIKELY ON THE OCEAN AND THE BAYS OF
LONG ISLAND. SCA ISSUED FOR THESE HAZARDS. TSTMS WILL ALSO BE A
HAZARD WITH A COLD FRONTAL PASSAGE THU AFTERNOON/EVENING.
OCEAN SEAS COULD BUILD TO AROUND 5 FT SAT NIGHT INTO SUNDAY...
AND AGAIN LATE SUNDAY INTO MONDAY MORNING. THEN A MORE PROLONGED
PERIOD OF 5-FT OCEAN SEAS IS POSSIBLE FROM MON NIGHT INTO MID
WEEK.
&&
.HYDROLOGY...
BASIN AVG QPF OF 1/2 TO 3/4 INCH POSSIBLE IN THE LOWER HUDSON
VALLEY AND NE NJ...WITH UP TO 1/2 INCH ELSEWHERE. WITH PW OVER 2
INCHES THU AFTERNOON AND EVENING...LOCALLY HEAVY RAINFALL IS
POSSIBLE WITH ANY STRONGER CONVECTION. MINOR URBAN/POOR DRAINAGE
FLOODING IS THE MOST LIKELY OUTCOME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NYZ072>075-176-
178.
HIGH RIP CURRENT RISK FROM 6 AM EDT THIS MORNING THROUGH THIS
EVENING FOR NYZ075-080-081-178-179.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS
EVENING FOR ANZ340-345.
SMALL CRAFT ADVISORY FROM NOON TODAY TO MIDNIGHT EDT TONIGHT
FOR ANZ355.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM EDT FRIDAY FOR
ANZ350-353.
&&
$$
SYNOPSIS...GOODMAN/JP
NEAR TERM...GOODMAN/JM/DS
SHORT TERM...GOODMAN/DS
LONG TERM...JP
AVIATION...MET
MARINE...GOODMAN/JP
HYDROLOGY...GOODMAN/JP
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
341 AM EDT THU JUL 30 2015
.DISCUSSION...
TODAY-TONIGHT...MODELS SHOW THAT THE AREA OF LOWER PRECIPITABLE
WATER VALUES...THAT SLIPPED INTO NORTHERN AREAS YESTERDAY...
MOISTENING BACK UP ABOVE 2 INCHES. THIS SEEMS REASONABLE AS THE
PERIPHERAL DRYING FROM LOW PRESSURE SYSTEM OFFSHORE NORTH FLORIDA
LIFTS FARTHER AWAY TO THE NORTHEAST.
HAD BEEN A BIT DUBIOUS ABOUT THE 50-70 POPS ADVERTISED BY MOS
ESPECIALLY SINCE THERE WAS CONSIDERABLE DEBRIS CLOUDINESS
OVERSPREADING THE PENINSULA FROM CONVECTION OFFSHORE. RECENT
TRENDS SHOW THE CLOUDS DIMINISHING...AND AS THE LOW PULLS SLOWLY
NORTHEAST...EXPECT THIS TREND TO CONTINUE. THEREFORE MOST PLACES
SHOULD HEAT UP TO AROUND 90 OR THE LOWER 90S. THE MODELS HAVE BEEN
SHOWING TEMPS ALOFT COOLING TO AROUND MINUS 7 CELSIUS. THEREFORE
EXPECT A FEW MORE STRONG STORMS...WITH FREQUENT LIGHTNING STRIKES
BEING THE MAIN DANGER. FORECAST SOUNDINGS SHOW SOME LINGERING
DRIER AIR ALOFT...SO ISOLATED STRONG WIND GUSTS 50-60 MPH COULD
OCCUR AGAIN.
AS FAR AS DISTRIBUTION/TIMING OF THE STORMS...WOULD EXPECT A
GENERAL SCENARIO SIMILAR TO YESTERDAY WITH SHOWERS/STORMS MOVING
ACROSS SOUTHERN SECTIONS EARLIEST (WHERE THE STRONGEST/DEEPEST
WESTERLY FLOW WILL EXIST). THE LOCAL WRF AND HRRR MODELS GENERALLY
SHOW THIS OCCURRING...WITH LATER AND SLOWER MOVING STORMS EXPECTED
ACROSS THE NORTH AS BOUNDARIES INTERACT. THESE STORMS COULD BE
THE STRONGEST OF THE DAY.
MOS HAS POPS 50-60 PERCENT IN THE SOUTH TONIGHT...BUT GIVEN THE
ABOVE DISCUSSION...HAVE TRENDED BELOW THOSE UN-CLIMATOLOGICAL
VALUES.
FRI-FRI NIGHT...WEAK AREA OF LOW PRESSURE AT 500 MB LINGERS OFF OF
THE IMMEDIATE EAST FLORIDA COAST WITH MID-LEVEL HIGH PRESSURE
RIDGING EXTENDING NORTH OF THE AREA ACROSS THE GULF COAST STATES.
AT THE SURFACE HIGH PRESSURE RIDGING REMAINS SUPPRESSED ACROSS THE
SOUTHERN FL PENINSULA/FL STRAITS. A WEAK AREA OF SURFACE LOW
PRESSURE OFF OF THE CAROLINAS EARLY IN THE PERIOD WILL LIFT FAIRLY
RAPIDLY NORTHEASTWARD AWAY FROM THE AREA. DEEP LAYER MOISTURE
CONTINUES WITH PRECIPITABLE WATER VALUES IN EXCESS OF 2 INCHES
ACROSS MUCH OF THE AREA. SUBTLE IMPULSES ALOFT...DEEP MOISTURE AND
BOUNDARY INTERACTIONS THROUGH THE DAY WILL ALLOW FOR HIGH END CHANCE
POPS (50 PERCENT) NEAR I-4 CORRIDOR NORTHWARD (AFTN/EVENING) AND
LIKELY CHANCES (60-70 PERCENT) SOUTHWARD. SCHC/LOW END CHC WORDING
FOR POPS DURING THE MORNING. LOWERING RAIN CHANCES FRI NIGHT THOUGH
REALISTICALLY THERE WILL REMAIN AT LEAST A SLIGHT CHANCE ACROSS ECFL
OVERNIGHT. STORM MOVEMENT MAINLY OUT OF THE SW OR W. HIGHS IN THE
U80S TO AROUND 90 AND LOWS GENERALLY IN THE M/U 70S.
WEEKEND...SURFACE RIDGE AXIS WILL REMAIN SITUATED OVER THE SOUTHERN
FL PENINSULA AS SSW/SW FLOW CONTINUES IN THE LOW-LEVELS. ALOFT...A
GENERALLY TROUGHY PATTERN CONTINUES ALONG THE EASTERN SEABOARD TO
INCLUDE THE FLORIDA PENINSULA. WE ALSO MAINTAIN THE DEEP MOISTURE
AND RELATIVELY WARM TEMPERATURES ALOFT. THE STORM MOTION WHILE WEAK
WILL GENERALLY FAVOR A WEST TO EAST MOVEMENT. LOCALLY HEAVY
RAINFALL...GUSTY WINDS AND CLOUD TO GROUND LIGHTNING WILL REMAIN THE
MAIN CONVECTIVE THREATS. WITH THIS PERSISTENT PATTERN WILL KEEP
LOWER END SCHC/CHC POPS DURING THE MORNING AND MAINLY LIKELY (60
PERCENT) MENTION FOR THE AFTERNOON/EARLY EVENING PERIODS. HIGHS/LOWS
WILL REMAIN CONSISTENT FROM WHAT WE HAVE BEEN SEEING RECENTLY.
MON-WED...ALOFT...AS THE HIGH PRESSURE RIDGING CONTINUES TO AMPLIFY
OVER THE WESTERN U.S. THE GENERAL TROUGHINESS WILL CONTINUE ACROSS
THE EASTERN CONUS. THE SURFACE ATLANTIC RIDGE WILL BEGIN BUILDING
BACK NORTHWARD TUE-WED AS THE EASTERN CONUS LOW-LEVEL TROUGHING
SHIFTS WEST OVER THE GULF OF MEXICO. EXPECT MOISTURE TO REMAIN HIGH
AND POPS 50 PERCENT OR A LITTLE HIGHER STILL SEEM WARRANTED...EXCEPT
POSSIBLY TRENDING LOWER WED...IF THE SURFACE RIDGE DOES INDEED BUILD
BACK INTO CENTRAL FLORIDA.
&&
.AVIATION...A FEW MVFR CEILINGS WILL OCCUR UNTIL A LITTLE AFTER
SUNRISE. THERE IS A LITTLE MORE LOW LEVEL WIND THIS MORNING...BUT
LOCAL IFR COULD BRIEFLY OCCUR TOO. THEN THE MAIN FORECAST PROBLEM
BECOMES THE TIMING OF STORMS. EXPECT THAT FROM ABOUT KVRB-KSUA
THERE WILL BE A CHANCE FOR STORMS RATHER EARLY AGAIN...ABOUT
16-20Z...WITH THE REMAINING TERMINALS LIKELY HAVING THE GREATEST
CHANCE BETWEEN 18-22Z. A FEW STRONG STORMS WITH WIND FREQUENT
LIGHTNING STRIKES AND GUSTY WINDS OVER 30 KNOTS ARE EXPECTED AGAIN.
&&
.MARINE...
TODAY-TONIGHT...SOUTHWEST WIND FLOW REGIME WILL CONTINUE WITH
SPEEDS 10-15 KNOTS OFFSHORE AND 5-10 KNOTS CLOSE TO THE COAST. THE
MAIN MARINER CONCERN WILL BE OFFSHORE MOVING SHOWERS/STORMS WHICH
COULD MOVE OFFSHORE THE TREASURE COAST BY EARLY AFTERNOON.
STEERING FLOW WILL BE WEAK NORTHWARD TO THE VOLUSIA COAST...BUT A
FEW STRONG STORMS COULD AFFECT THE NEARSHORE WATERS LATE IN THE
AFTERNOON.
FRI-FRI NIGHT...SURFACE RIDGE AXIS REMAINS SUPPRESSED TO THE SOUTH.
MAINLY SSW/SW WINDS AROUND 10 KTS. SEAS GENERALLY AOB 3 FT.
WINDS/SEAS LOCALLY HIGHER INVOF OF STRONGER CONVECTION. OFFSHORE
MOVING STORM CELLS REMAIN A THREAT THROUGH THE PERIOD. COVERAGE OF
SHOWERS/STORMS LOOKS RATHER HIGH AND STORMS SHOULD START TO PRODUCE
MORE FREQUENT LIGHTNING STRIKES.
SAT-MON...SURFACE RIDGE AXIS ACROSS THE SOUTHERN PENINSULA INTO
EARLY NEXT WEEK. LITTLE CHANGE IN MOIST SSW/SW WIND FLOW REGIME.
STORM MOTION STILL OFFSHORE BUT WEAKER. BOATERS SHOULD CONTINUE TO
BE VIGILANT FOR MARINE STORMS... ESPECIALLY DURING THE AFTERNOON AND
EVENING. WIND SPEEDS AOB 15 KTS WITH SEAS 2-4 FT GENERALLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 90 74 90 74 / 60 30 50 30
MCO 91 74 90 74 / 60 30 50 30
MLB 91 73 89 74 / 60 30 60 40
VRB 90 73 89 72 / 60 30 70 40
LEE 89 76 91 76 / 60 30 50 30
SFB 92 75 91 74 / 60 30 50 30
ORL 91 76 90 75 / 60 30 50 30
FPR 90 73 89 73 / 60 30 70 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....SEDLOCK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1129 PM MDT WED JUL 29 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 221 PM MDT WED JUL 29 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS WEST-
NORTHWEST FLOW ACROSS NORTHERN PLAINS WITH BROAD RIDGE ACROSS THE
SOUTHERN US AND TROUGH ACROSS THE NORTHERN GREAT LAKES. AT THE
SURFACE HIGH PRESSURE EXTEND FROM THE NORTHERN PLAINS ACROSS
WESTERLY KANSAS.
THIS AFTERNOON-TONIGHT...AXIS OF FAVORABLE LAPSE RATES (AROUND
7C/KM) IS IN THE PROCESS OF SHIFTING EAST WITH WEAK SHORTWAVE
TROUGH. AS THIS SHIFTS EAST CHANCE FOR SPRINKLES/LIGHT SHOWERS
COMES TO AN END (BY EARLY EVENING). LOW TEMPS TONIGHT WILL BE VERY
SIMILAR TO LAST NIGHT WITH NEAR SEASONAL VALUES AROUND 60F...AND
SOME COOLER LOCATIONS IN THE MID-UPPER 50S.
THURSDAY...H5 RIDGE BEINGS TO AMPLIFY ACROSS WESTERN US RESULTING
IN STRENGTHENING OF LEE TROUGH AND INCREASE IN WAA ACROSS EASTERN
COLORADO/FAR WESTERN KANSAS. TEMPS WILL APPROACH SEASONAL VALUES
IN THE UPPER 80S/NEAR 90 FOR MOST PARTS OF OUR CWA. STEEP MID
LEVEL LAPSE RATES AND 400-700 J/KG CAPE AXIS BEGINS TO BUILD BACK
OVER THE WESTER CWA...WHICH COULD RESULT IN THUNDERSTORM
DEVELOPMENT POSSIBLY AS EARLY AS MID MORNING THURSDAY. BEST
SURFACE CONVERGENCE IS WEST OF CWA...SO UNTIL WEAK ENERGY TOWARDS
THE CWA FROM THE SW DURING THE AFTERNOON WE PROBABLY WONT SEE ANY
ACTIVITY. BEST LIFT IS ALSO SOUTH OF OUR CWA...SO CONFIDENCE IS
LOW ON COVERAGE AT THIS POINT. BEST SIGNAL/CHANCES WILL BE ACROSS
THE WEST ROUGHLY ALONG KS/CO STATE LINE. WITH WEAK CAPE VALUES
SEVERE POTENTIAL IS VERY LOW DESPITE INCREASING EFFECTIVE SHEER
LATE THURSDAY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 145 PM MDT WED JUL 29 2015
THE LONG TERM FORECAST PERIOD WILL BE DOMINATED BY AN UPPER LEVEL
HIGH PRESSURE SYSTEM POSITIONED OVER THE SOUTH CENTRAL CONUS...WHICH
WILL BRING THE RETURN OF NEAR NORMAL TEMPERATURES IN THE LOWER TO
MID 90S ON FRIDAY. THE UPPER LEVEL RIDGE WILL CONTINUE TO AMPLIFY
OVER THE WESTERN THIRD OF THE CONUS ON FRIDAY...WHICH WILL BRING
MOSTLY DRY CONDITIONS. HOWEVER...A FRONTAL BOUNDARY WILL BE
POSITIONED OVER THE SOUTH/SOUTHWEST CORNER OF THE FORECAST AREA
WHICH WILL BRING SOME CHANCES FOR SOME DEVELOPING SHOWERS AND
THUNDERSTORMS FOR FRIDAY THROUGH SATURDAY. SEVERE INDICATORS AT
THIS TIME LOOK MARGINAL AT BEST...SO SEVERE WEATHER IS NOT
ANTICIPATED AT THIS TIME.
AS UPPER LEVEL RIDGE AMPLIFIES OVER THE WEEKEND WITH A LACK OF A
SURFACE FORCING MECHANISM...SO EXPECTING DRY WEATHER FOR THE REST OF
THE WEEKEND SATURDAY NIGHT THROUGH SUNDAY. WARM SURFACE SOUTHERLY
FLOW WILL CONTINUE TO BRING INCREASED MOISTURE WITH DEW POINTS IN
THE MID 60S AND TEMPERATURES IN THE UPPER 80S TO LOWER 90S.
THE NEXT CHANCES FOR PRECIPITATION WILL BE TUESDAY AS AN UPPER LEVEL
SHORTWAVE TROUGH APPROACHES THE CENTRAL HIGH PLAINS REGION. MODEL
FORECASTS DIFFER AS TO THE LOCATION AND TIMING OF THE FEATURE...WITH
THE ECMWF BRINGING THE DISTURBANCE IN THE FASTEST STARTING TUESDAY.
AT THIS POINT...NOT VERY CONFIDENT THAT SHOWERS AND STORMS WILL
DEVELOP CONSIDERING GFS/CANADIAN/DGEX MODELS ALL INDICATE THE RIDGE
MAINTAINING STRENGTH OVER THE REGION. TO STAY WITHIN FORECAST
COLLABORATION THRESHOLDS...KEPT CHANCES FOR PRECIPITATION IN THE
FORECAST...ESPECIALLY CONSIDERING THAT THE ECMWF TENDS TO LATCH ON
TO FORECAST PATTERNS SOONER THAN THE OTHER MODELS IN THE LONG TERM
PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1127 PM MDT WED JUL 29 2015
VFR CONDITIONS EXPECTED FOR THE 6Z TAFS. LIGHT WINDS WILL CONTINUE
THROUGH THE TAF PERIOD. SOUTHERLY WINDS TONIGHT WILL GRADUALLY
TURN TO THE SOUTHEAST DURING THE AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS JACKSON KY
243 AM EDT THU JUL 30 2015
.UPDATE...
ISSUED AT 243 AM EDT THU JUL 30 2015
COLD FRONT WAS POSITIONED FROM NEAR KBNA TO NEAR KDAY. CONVECTION
HAS ALMOST DIED OUT OVER THE LOCAL AREA...BUT CAN NOT RULE OUT
SOMETHING POPPING UP YET AHEAD OF THE FRONT. HAVE LOWERED POPS TO
20 PERCENT...AND THEN DROPPING BELOW THE THRESHOLD FOR THE MENTION
OF PRECIP AFTER THE FRONT PASSES SOUTHEAST IN THE MORNING.
UPDATE ISSUED AT 1020 PM EDT WED JUL 29 2015
THE COLD POOL ASSOCIATED WITH THE LINE OF STORMS HAS CONTINUED TO
CONSOLIDATE TO THE WEST AND SOUTH OF OUR AREA. ONLY A FEW OF OUR
SOUTHWEST COUNTIES WILL SEE LIKELY RAINS OVER THE NEXT HOUR OR SO.
THE REMNANT STRATIFORM RAINFALL ACROSS CENTRAL KENTUCKY IS NOT
MOVING MUCH...AND WILL GRADUALLY WEAKEN...MAINLY IN PLACE. THE
LAST FEW RUNS OF THE HRRR HAS GENERALLY CAUGHT ON TO THE ONGOING
CONVECTIVE TRENDS. AS SUCH...IT APPEARS THAT THERE MAY NOT BE MUCH
IN THE WAY OF ACTIVITY UNTIL THE ACTUAL FRONTAL BOUNDARY MOVES
SOUTHEAST ACROSS THE AREA DEEPER INTO THE OVERNIGHT HOURS...WHEN A
SLIGHT UPTICK IN ACTIVITY MAY OCCUR. WILL THEREFORE HANG ONTO
SLIGHT TO CHANCE POPS. ALSO ADJUSTED THE LOWS UP A TOUCH...AS THE
PUSH BEHIND THE FRONT IS NOT VERY STRONG. THE BEST CHANCE OF
SEEING SOME UPPER 60 DEGREE READINGS LOOKS TO BE ALONG AND NORTH
OF I-64. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 813 PM EDT WED JUL 29 2015
THE LATEST RADAR MOSAIC SHOWS A CONVECTIVE LINE ACROSS CENTRAL
AND WESTERN KENTUCKY. NEW CELLS HAD BEEN MORE LIVELY A BIT FURTHER
NORTHEAST EARLIER...BUT SOME PRECURSORY STORMS TAPPED INTO THE
BETTER AVAILABLE AIR MASS...AND NOW THERE IS GENERALLY A WEAKENING
TREND ON THE EASTERN FLANK OF THE LINE...WITH BETTER COLD POOL AND
ASSOCIATED NEW DEVELOPMENT ALIGNING MORE TOWARDS THE SOUTH...WHERE
BETTER INSTABILITY REMAINS. STILL...THINK THAT SOME DEBRIS CELLS
WILL MAKE IT INTO THE WEST IN THE NEXT 1 TO 2 HOURS...AND HAVE
UPPED THE POPS TO HIGH CHANCE TO LIKELY FOR THOSE LOCATIONS. AS WE
LOSE HEATING...EXPECT AN OVERALL GRADUAL DIMINISHMENT...HOWEVER
WILL STILL HAVE TO KEEP AN EYE ON HEAVY RAINERS...GIVEN THE HIGH
PWATS AND THE POTENTIAL FOR TRAINING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 343 PM EDT WED JUL 29 2015
AS OF MID AFTERNOON A MID LEVEL RIDGE WAS CENTERED OVER THE
SOUTHERN PLAINS REGION...WITH A CLOSED MID LEVEL LOW OVER
NORTHWESTERN ONTARIO AND THE ASSOCIATED TROUGH SOUTH INTO THE MS
VALLEY REGION. AT THE SFC...AN AREA OF LOW PRESSURE WAS CENTERED
OVER ONTARIO WITH A COLD FRONT SOUTH INTO THE CENTRAL GREAT LAKES
AND THEN SOUTHWEST INTO THE MID MS VALLEY AND CENTRAL PLAINS.
CONVECTION HAS DEVELOPED ALONG OR IN ADVANCE OF THIS FRONT OVER OH
AND IN SOUTHWEST INTO WESTERN KY. ADDITIONAL CONVECTION HAS
DEVELOPED NEAR A MOISTURE GRADIENT EVIDENT IN PW FROM NORTHERN KY
SOUTH INTO CENTRAL KY. THIS CONVECTION HAS BEEN GENERALLY SLOW
MOVING WITH HEAVY RAINFALL RATES. AREA WIDE...A WARM AND MOIST
AIR MASS IS IN PLACE WITH TEMPERATURES IN THE MID TO UPPER 80S TO
NEAR 90 AND DEW POINTS IN THE UPPER 60S TO MID 70S.
THE CLOSED MID LEVEL LOW WILL TRACK TO HUDSON BAY WITH THE
TRAILING SHORTWAVE TROUGH MOVING THROUGH THE GREAT LAKES AND MID
AND UPPER OH VALLEY REGION TONIGHT. THIS SHORTWAVE TROUGH WILL
MOVE INTO THE NORTHEASTERN CONUS THROUGH THURSDAY. AT THE SAME
TIME...THE MID LEVEL RIDGE WILL RETROGRADE AND AMPLIFY AND BECOME
CENTERED OVER THE SOUTHERN ROCKIES OR FOUR CORNERS REGION. THIS
WILL PUT THE REGION IN NW FLOW ALOFT LATE IN THE PERIOD. AT THE
SFC...THE COLD FRONT WILL CROSS THE REGION BY LATE TONIGHT OR
EARLY ON THURSDAY. THEN...HIGH PRESSURE WILL BUILD IN BEHIND THE
DEPARTING COLD FRONT AND USHER IN SLIGHTLY COLDER...BUT MORE
NOTICEABLY DRIER AIR INTO THE REGION.
RATHER MEAGER MID LEVEL FORCING AND NON OPTIMAL TIMING OF THE
FROPA DURING THE LATE EVENING INTO OVERNIGHT HOURS SHOULD LIMIT
CONVECTION THIS EVENING AND TONIGHT TO ISOLATED TO SCATTERED
COVERAGE. IT STILL APPEARS THAT THERE SHOULD BE A PEAK IN COVERAGE
OVER THE NEXT 3 HOURS OR SO...AND THEN MORE ORGANIZED CONVECTION
WITH A POSSIBLE BROKEN LINE OR LINE SEGMENTS OF SHOWERS AND
THUNDERSTORMS AS THE COLD FRONT MOVES THROUGH. WITH RELATIVELY
SLOW STORM MOTIONS EXPECTED DUE TO WEAK FLOW ALOFT AND A MOIST
AIR MASS IN PLACE...ANY STRONGER THUNDERSTORMS COULD PRODUCE VERY
HEAVY RAINFALL RATES AND OUTFLOW WIND GUSTS IN EXCESS OF 30 MPH
WILL BE POSSIBLE THIS EVENING SIMILAR TO A GUST OBSERVED OVER
CENTRAL KY EARLIER THIS AFTERNOON.
A SHOWER OR POSSIBLY A THUNDERSTORM COULD LINGER EARLY ON
THU...OVER THE SOUTHEASTERN CWA...PARTICULARLY NEAR THE VA BORDER.
OTHERWISE... AS DRIER AIR MOVES IN THROUGHOUT THE COLUMN SKIES
SHOULD BECOME MOSTLY SUNNY IN MOST LOCATIONS ON THU AFTERNOON.
WITH THE HIGH BUILDING IN...CLEAR SKIES AND LIGHT WINDS SHOULD SET
THE STAGE FOR VALLEY FOG FORMATION LATE IN THE PERIOD. ENOUGH
DRIER AIR SHOULD WORK IN FOR SOME OF THE NORMALLY COLDER LOCATIONS
ALONG...OR NORTH OF THE MTN PARKWAY COULD TOUCH THE UPPER 50S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 256 PM EDT WED JUL 29 2015
THE EXTENDED PERIOD LOOKS FAIRLY BENIGN AS SURFACE HIGH PRESSURE
TAKES CONTROL OF THE REGION THROUGH EARLY NEXT WEEK. THIS WILL
ALLOW FOR SLIGHTLY COOLER AND DRIER AIR TO FILTER INTO THE REGION
FOR THE WEEKEND. HIGHS FRIDAY THROUGH SUNDAY WILL BE IN THE LOW TO
MID 80S...BUT DEW POINTS IN THE UPPER 50S AND LOW 60S WILL MAKE
THOSE READINGS FEEL MUCH MORE PLEASANT THAN THEY HAVE RECENTLY.
A WEAK AND MOISTURE STARVED FRONT APPROACHES THE REGION SATURDAY
MORNING...WITH BOTH THE GFS AND ECMWF SHOWING THE PRECIP FALLING
APART BEFORE IT REACHES THE FORECAST AREA. THIS IS LIKELY DUE TO
THE DRY AIR/RIDGING AT THE SURFACE. THERE IS SOME MID LEVEL
MOISTURE AND WEAK ENERGY WITH THE FRONT AS IT PASSES TO OUR NORTH
SO HAVE KEPT A SLIGHT CHANCE OF AN ISOLATED SHOWER IN THE FAR
NORTHERN COUNTIES. BUT DO NOT EXPECT MUCH MORE THAN AN INCREASE IN
SOME MID LEVEL CLOUDS ON SATURDAY FOR MOST AREAS.
SHOWER CHANCES RETURN TO THE REGION BY TUESDAY AS THE UPPER LEVEL
PATTERN BECOMES MORE ACTIVE. MODELS INDICATE THAT SEVERAL UPPER
LEVEL IMPULSES EMBEDDED IN THE NW FLOW WILL MOVE ACROSS EASTERN
KENTUCKY THROUGH THE END OF THE FORECAST PERIOD BRINGING INCREASED
SHOWER AND THUNDERSTORM CHANCES THROUGH THE END OF THE WORK WEEK.
TEMPERATURES (AND HUMIDITY) WILL INCREASE BACK INTO THE UPPER 80S
BY THE END OF THE PERIOD...WITH HEAT INDICES LIKELY SURPASSING THE
90 DEGREE MARK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 243 AM EDT THU JUL 30 2015
CONDITIONS WERE MOSTLY VFR AT THE START OF THE PERIOD. A
DETERIORATION TO IFR AND MVFR IS EXPECTED OVERNIGHT. IMPROVEMENT
BACK TO VFR SHOULD OCCUR ON THURSDAY MORNING. A SHOWER OR
THUNDERSTORM WILL BE POSSIBLE UP UNTIL A COLD FRONT MOVES THROUGH
FROM NW TO SE. THIS WILL HAPPEN BETWEEN ABOUT 09Z AND 16Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...JP
LONG TERM...JVM
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1140 PM CDT WED JUL 29 2015
.AVIATION...HRRR HAS LATE EVENING CONVECTION NEAR THE COAST AROUND
CAMERON AND THIS IS CONFIRMED BY THE CURRENT RADAR. HRRR TAKES
CONVECTION IN THE ATCHAFALAYA BASIN AND MOVES IT INTO THE ACADIANA
AIRPORTS LFT AND ARA SO ADDED VCTS FOR THE NEXT FEW HOURS. LATER
TNITE THIS ACTIVITY MOVES INTO THE LCH AREA. AFTER THE ATMOSPHERE
SETTLES IN THE MORNING, CONVECTION REGENERATES WITH AFTERNOON
HEATING SO ADDED VCTS AGAIN FOR THE TERMINALS. UPPER LEVEL
DIFLUENCE IS ACTING ON CONVECTION TNITE AND ADDITIONAL MID LEVEL MOISTURE
IS INDICATED ON THURSDAY.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 1010 PM CDT WED JUL 29 2015/
DISCUSSION...
REGIONAL 88DS SHOW A FAIR AMOUNT OF CONVECTION ONGOING MAINLY OVER
SERN LA...ALTHOUGH IT DOES SPILL OVER INTO LOWER ACADIANA/CAMERON
PARISH. LAST SEVERAL RADAR SCANS...AS WELL AS IR IMAGERY...SHOW
THIS ACTIVITY WEAKENING A BIT AS DAYTIME HEATING GRADUALLY WANES.
EVENING GRIDS/ZONES WERE ADJUSTED TO ACCOUNT. LEFT THE OVERNIGHT
GRIDS ALONE AS THE RECENT TREND FOR NOCTURNAL CONVECTION SKIRTING
THE COASTLINE SHOULD AGAIN BE THE RULE WITH RIDGING ALOFT SITUATED
OVER THE WRN GULF STATES. ELSEWHERE TWEAKS TO GRIDS/ZONES WERE
MINOR...UPDATE ALREADY SENT.
25
PREV DISCUSSION... /ISSUED 657 PM CDT WED JUL 29 2015/
AVIATION...VCTS ENDING SOON AT LCH, LFT, AND ARA. VFR WITH AGAIN
VCTS BY MID-AFTERNOON THURSDAY FOR THE SOUTHERN TERMINALS AS
MOISTURE DEEPENS ON THURSDAY INTO FRIDAY.
SWEENEY
PREV DISCUSSION... /ISSUED 320 PM CDT WED JUL 29 2015/
DISCUSSION...
WX MAP SHOWS HIGH PRESSURE RIDGE AT THE SFC ACROSS THE N GULF...WITH
HIGH PRESSURE CONTINUING OVER THE ARKLATEX. LCH WSR88D SHOWS A FEW
SHRA ALONG THE COASTAL PARISHES ...OCCASIONAL TSRA...ALONG THE
I-10 CORRIDOR ACROSS SE TX/S LA THIS AFTERNOON. TEMPS IN THE UPPER
90S ALONG AND N OF I-10...WITH A FEW 100S SPRINKLED ACROSS C LA.
BUT WITH DEWPTS RANGING FROM THE UPPER 60S/LOWER 70S INLAND...KEEPIN
THE HEAT INDEX VALUES 102-106. FOR THIS EVENING...SHRA/TSRA EXPECTED
TO DISSIPATE BY SUNSET...BUT INCREASED MOISTURE FROM THE SE MAY
KEEP ISO SHRA/TSRA ACROSS THE EASTERN COASTAL WATERS.
BY THU AND INTO THE WEEKEND...THE RIDGE ALOFT EXPECTED TO BREAK
DOWN A BIT OVER OUR REGION AND RETROGRADE WESTWARD AS A LONGWAVE
TROF DIGS SOUTH OVER THE EAST COAST. THIS SHOULD ALLOW FOR A WEAK
COOL FRONT TO MOVE FROM THE NORTH. AHEAD OF THE BOUNDARY...SUBSIDENCE
LIKELY TO BUMP UP TEMPS BACK INTO THE UPPER 90S TO NEAR 100 FOR
MOST AREAS N OF I-10. DEWPTS EXPECTED TO BE A COUPLE OF DEGREES
HIGHER IN THE LOWER/MID 70S DUE TO SLIGHTLY INCREASE LOW LEVEL
MOISTURE FROM THE EAST. THUS...HEAT INDEX VALUES LIKELY TO REACH
108-110 FOR THE AFTERNOON HOURS. HEAT ADVISORY MAY BE NEEDED FOR
THE AFTERNOON HOURS FOR THE AREAS IN THE 109-110 RANGE...WHICH
LOOKS TO BE MOST OF LOWER SE TX AND MOST OF C AND S LA.
THE OTHER ISSUE WILL BE THE INITIATION OF SHRA/TSRA AHEAD OF THE
FRONT AS LOW LEVEL MOISTURE AND INSTABILITY INCREASES FROM THE
EAST. TIMING ON THIS WILL LIKELY BE JUST AFTER THE HIGH TEMPERATURES
ARE REACHED...WITH THE BEST CHANCES AND COVERAGE OF SHRA/TSRA EXPECTED
OVER SC LA INTO THE COASTAL WATERS. THIS IS EXPECTED TO CONTINUE
THRU THE EVENING HOURS ACROSS MOST OF S LA...INTO THE COASTAL WATERS
FRI MORNING.
FOR FRI...SLIGHTLY DRIER AIR WITH DEWPTS IN THE 60S ACROSS INLAND
SE TX/C LA WILL LESSEN THE HEAT INDEX VALUES SOMEWHAT. OTHERWISE...NOT
MUCH IF ANY COOLER TEMPS EXPECTED WITH THIS FRONT. BY THE WEEKEND
INTO MON...THE UPPER RIDGE EXPECTED TO CONTINUE RETROGRADING
WESTWARD AS THE LONG WAVE TROF BROADENS OVER THE C AND E U.S. BY
TUE & WED...THE RIDGE ALOFT BUILDS BACK EASTWARD OVER TX/LA...WITH
THE WARMER THAN NORMAL TEMPS RESUMING.
DML
MARINE...
LIGHT AND VARIABLE WINDS ARE EXPECTED TONIGHT...WITH A MORE
PREVALENT WEST TO NORTHWEST FLOW DEVELOPING ON THURSDAY AS A WEAK
FRONTAL BOUNDARY SAGS INTO THE REGION. THIS FRONT...COUPLED WITH
INCREASING MOISTURE FROM THE EASTERN GULF...WILL SIGNIFICANTLY
INCREASE THE CHANCES OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT
INTO FRIDAY. THE FRONT IS EXPECTED TO STALL NEAR THE COAST...KEEPING
ELEVATED CHANCES OF SHOWERS AND THUNDERSTORMS INTO THE WEEKEND.
DML
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 77 99 75 97 / 10 20 20 20
LCH 77 98 78 96 / 20 30 30 20
LFT 77 98 77 96 / 20 40 30 30
BPT 77 98 78 97 / 20 20 20 20
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AVIATION...11
AREA FORECAST DISCUSSION
NWS CARIBOU ME
104 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA ON THURSDAY BRINGING SHOWERS AND
THUNDERSTORMS. AN UPPER DISTURBANCE WILL CROSS NORTHERN MAINE ON
FRIDAY. ANOTHER FRONT WILL PUSH THROUGH THE STATE ON SATURDAY AND
SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TODAY/...
1 AM UPDATE...ADJUSTED THE POP GRIDS TO PLAY FOR SOME LIGHT
SHOWERS(20%) MOVING ACROSS THE W AND NW BY SUNRISE W/THE WARM
FRONT. THE HRRR 3KM MODEL WAS MATCHING WELL W/THE MOSAIC RADAR
LOOP SHOWING SOME LIGHT SHOWERS IN QUEBEC. KEPT THE MENTION OF FOG
IN THE FORECAST THROUGH THE MORNING W/THE DOWNEAST COAST SEEING
THE MOST DENSE FOG DUE TO SSE FLOW.
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS EXPECTED ON
THURSDAY AS A COLD FRONT PUSHES ACROSS THE STATE. STORMS COULD BE
STRONG TO SEVERE DURING THE AFTERNOON AND EVENING. READ ON FOR
DETAILS...
FOR THURSDAY...THE AFOREMENTIONED STATIONARY FRONT WILL LIFT NORTH
DURING THE AFTERNOON AS LOW PRESSURE SLIDES EASTWARD THROUGH EASTERN
CANADA. A COLD FRONT WILL QUICKLY FOLLOW FROM WEST TO EAST, CROSSING
THE STATE DURING THE LATE AFTERNOON INTO THE EVENING HOURS. SHOWERS
AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OUT AHEAD OF THE COLD
FRONT AND ENTER NORTHWESTERN MAINE AROUND MID AFTERNOON. ALTHOUGH
THERE`S DIFFERING OPINIONS BETWEEN THE MODELS ON HOW MUCH SURFACE
CAPE WILL BE AROUND (500-1200 J/KG ON GFS VS 800-2000 J/KG ON NAM),
AT LEAST THEY AGREE THAT THE BEST INSTABILITY WILL BE ACROSS WESTERN
MAINE, ROUGHLY ALONG AND WEST OF ROUTE 11. HOWEVER, MID-LEVEL LAPSE
RATES LOOK GOOD EVERYWHERE, RUNNING AT 6-7 C/KM. SHEAR WILL INCREASE
THROUGH THE AFTERNOON AND BE 30-35 KT BY EVENING. WOULD EXPECT WINDS
TO BE THE BIGGEST THREAT AS FREEZING LEVELS WILL RISE TO 12+ KFT,
BUT CAN`T RULE OUT SOME LARGE HAIL, ESPECIALLY IN ANY STORMS THAT
MANAGE TO ROTATE. HEAVY RAIN WILL BE A CONCERN AS WELL; PWATS WILL
APPROACH 2 INCHES AS MOISTURE INCREASES IMMEDIATELY AHEAD OF THE
FRONT. CORFIDI VECTORS INDICATE THAT WE COULD SEE TRAINING CELLS
AND/OR SLOW FORWARD MOVEMENT, WHICH WOULD ENHANCE THE FLOOD THREAT.
THE SPC CONTINUES TO INCLUDE ALL OF OUR AREA EXCEPT FAR DOWNEAST IN
A MARGINAL RISK FOR SEVERE WEATHER TOMORROW. HAVE CONTINUED WITH
ENHANCED WORDING IN THE FORECAST.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
SCTD TO NUMEROUS THUNDERSTORMS WILL BE ONGOING ACROSS THE FCST
AREA AT THE BEGINNING OF THE FORECAST PERIOD. SOME OF THE STORMS
COULD PRODUCE HEAVY RAIN...ALONG WITH WITH LARGE HAIL AND DAMAGING
WINDS. ALTHOUGH BY THE EVENING HOURS...THE STORMS SHOULD BE
WEAKENING QUICKLY. A CHANCE OF SHOWERS AND STORMS WILL CONTINUE
ACROSS THE CROWN OF MAINE ON FRIDAY...THEN SPREAD FARTHER SOUTH AS
ANOTHER WEAK UPPER LEVEL SYSTEM PROPAGATES ACROSS NEW ENGLAND ON
SATURDAY. TEMPERATURES WILL REMAIN ABOVE NORMAL WITH HIGHS RANGINGFROM
THE MID 70S TO LOWER 80S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED MODELS ARE IN GOOD AGREEMENT THROUGH THE PERIOD. THE
PRIMARY WEATHER FEATURES THROUGH THE PERIOD AFFECTING LOCAL
WEATHER WILL BE A HIGH PRESSURE RIDGE TO THE SOUTH...AND A CLOSED
UPPER LEVEL LOW OVER NRN CANADA. UNSETTLED WEATHER THROUGH THE
PERIOD...WITH TROUGHS ABOUT 12 TO 18 HRS APART WILL TRANSIT
THROUGH THE AREA BRINGING SHOWERS AND POSSIBLE TSTMS TO THE AREA.
THE GFS/ECMWF SUN AND MON ARE IN GOOD AGREEMENT WITH SHWRS AND
POSSIBLE TSTMS DURING THE MRNG HRS. BY TUES THE TIMING BEGINS TO
DIFFER WITH THE GFS ABOUT 6 HRS AHEAD OF THE ECMWF.
LOADED SUPERBLEND THROUGH THE PERIOD. LOADED NAWAVE4 FOR SEAS IN
THE COASTAL WATERS...ADDED 15 PERCENT TO WNDS FOR GUSTS OVER LAND
25 PERCENT FOR GUSTS OVER THE COASTAL WATERS.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR CONDITIONS EXPECTED TO PREVAIL INTO THURSDAY
MORNING. LOCAL IFR IN FOG IS POSSIBLE TONIGHT, MAINLY ALONG THE
COAST. COASTAL OBSERVATIONS ARE NEARING 100 PERCENT RH, SO FOG
DEVELOPMENT SHOULDN`T BE TOO FAR AWAY. TOUGH CALL ON WHETHER
BANGOR WILL FOG IN. IF THEY DO, THINK THAT IT WILL HOLD OFF UNTIL
AFTER MIDNIGHT AND NOT BE TOO DENSE. A COLD FRONT WILL BRING
SHOWERS AND THUNDERSTORMS TO THE AREA THURSDAY AFTERNOON WITH
MVFR/IFR POSSIBLE WHERE THE STORMS OCCUR.
SHORT TERM: THERE IS SMALL RISK OF STRONG TO SEVERE STORMS ACROSS
THE CWA EARLY THURSDAY EVENING...WHICH COULD PRODUCE HEAVY
RAIN...LARGE HAIL AND STRONG/GUSTY WINDS. ANY STRONG/SEVERE STORMS
SHOULD WEAKEN TO BELOW SEVERE LEVELS BY MIDNIGHT. THEN SCATTERED SHOWERS
AND STORMS WILL AFFECT THE NORTHERN HALF OF MAINE FRIDAY INTO
SATURDAY. REDUCED VSBYS AND CIGS WILL PROBABLY ACCOMPANY THE
STRONGER SHOWERS AND STORMS.
&&
.MARINE...
NEAR TERM: NO HEADLINES ARE ANTICIPATED. MAIN CONCERN WILL BE
RESTRICTED VISIBILITY IN FOG TONIGHT AND THURSDAY MORNING.
SHORT TERM: THERE IS A CHANCE OF THUNDERSTORMS ACROSS THE COASTAL
MAINE ZONES THURSDAY NIGHT. OTHERWISE CONDITIONS SHOULD BE QUITE
WITH WAVES/CIGS STAYING BELOW SCA CRITERIA.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
526 AM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 526 AM EDT THU JUL 30 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS A PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA WHILE A BROAD RIDGE
REMAINS ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE
FEATURES A NW FLOW WILL DOMINATE THE GREAT LAKES REGION ALLOWING A
SERIES OF MAINLY WEAK AND MOISTURE STARVED SHORTWAVES TO PASS THRU
AREA RESULTING IN PERIODIC LIGHT PCPN. TYPICALLY...THESE WEAK
SHORTWAVES ARE POORLY RESOLVED BY MODELS WHICH WILL MAKE FOR A
TRICKY FCST IN THE LONG TERM. IT LOOKS LIKE TEMPERATURES WILL BE
NEAR NORMAL THROUGH THE WEEKEND AND THEN PERHAPS TREND BELOW NORMAL
FOR THE EARLY PART OF NEXT WEEK BEHIND AS A MORE AMPLIFIED SHORTWAVE
AND ASSOC COLD FRONT PASS THROUGH THE UPPER GREAT LAKES REGION.
FRI INTO SAT...MOST OF MODELS HINT AT A FEW WEAK SHORTWAVES MOVING
THROUGH THE AREA...ONE FRI MORNING AND ANOTHER FRI NIGHT. WITH
SEVERAL OF THE MODELS SHOWING 100-300 J/KG OF MLCAPE AHEAD OF THESE
WAVES WILL PROBABLY NEED TO MAINTAIN AT LEAST SLIGHT CHC POPS FOR
ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW EXPECT ANY PCPN
FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
SATURDAY LOOKS TO BE TRENDING DRIER AS MOST OF THE MODELS INDICATE
SHORTWAVE ENERGY PASSING EAST OF THE AREA SAT MORNING...ALTHOUGH A
POCKET OF HIGHER INSTABILITY NOTED ALONG LAKE MI COUNTIES MAY STILL
WARRANT SLIGHT CHC POPS THERE.
TEMPERATURES FRI THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS COMING INTO A LITTLE BETTER AGREEMENT ON TIMING OF STRONGER
SHORTWAVE COMING DOWN FM SCNTRL CANADA AND ASSOC COLD FROPA FOR SUN
NIGHT/MON TIME FRAME. WILL CONTINUE LOW CHC POPS 30-40 PCT AT THIS
TIME...AND GIVEN STRENGTH OF SHORTWAVE THIS MAY BE BEST OPPORTUNITY
TO SEE WIDEPSREAD ALBEIT LIGHT PCPN. MODELS ADVERTISE BELOW NORMAL
TEMPS FOR MON-WED IN THE WAKE OF THE FROPA AS LATEST 00Z ECMWF SHOWS
8H TEMPS DROPPING TO 4-6C BY MON EVENING AND THEN PERSISTING IN THAT
RANGE INTO WED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 803 PM EDT WED JUL 29 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WHILE GUSTY W TO WSW
WINDS WILL SUBSIDE THIS EVENING AT KIWD/KSAW...EXPECT GUSTS TO
AROUND 25KT TO CONTINUE THRU THE NIGHT AT THE MORE EXPOSED KCMX
SITE. AFTER SUNRISE AND ONSET OF DAYTIME HEATING...GUSTY WINDS TO 20-
25KT WILL RETURN TO KIWD/KSAW...AND GUSTS WILL INCREASE TO AROUND
30KT AT KCMX. THERE MAY BE ISOLD SHRA NEAR KIWD THU AFTN...BUT
POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE IS TOO LOW TO INCLUDE
ANY MENTION IN FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HHUDSONBAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE
WEST-NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
446 AM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 239 PM EDT WED JUL 29 2015
IMPACTS...WITH LIMITED CHANCES FOR PRECIP...WILL HAVE TO KEEP
WATCHING FIRE WEATHER.
A LOW PRESSURE SYSTEM WILL HANG OUT OVER HUDSON BAY FROM THU NIGHT
THROUGH AT LEAST THE WEEKEND...SENDING SEVERAL WAVES ACROSS THE AREA
THROUGH DURING TIME. PREDICTABILITY OF THE WAVES IS POOR AS MODELS
STRUGGLE TO CONSISTENTLY RESOLVE THE FEATURES. AVAILABLE MOISTURE IS
ALSO ON THE LOW SIDE...LIMITING PRECIP COVERAGE AND AMOUNTS. WILL
KEEP SLIGHT CHANCE POPS OVER AT LEAST PORTIONS OF THE AREA EACH
PERIOD. TEMPERATURES LOOK TO BE NEAR NORMAL.
FRI LOOKS PRETTY DRY WHEN LOOKING AT THE SFC RH DROPPING INTO THE MID
TO UPPER 30 PERCENT RANGE. WINDS WILL GUSTS TO 20-25MPH...MAKING FOR
SOMEWHAT ELEVATED FIRE WEATHER CONCERNS.
MODELS SHOW THE LOW SHIFTING TO THE SE IN THE EARLY TO MIDDLE PART
OF NEXT WEEK...BUT HOW MUCH AND HOW FAST IS UNCERTAIN. IT DOES LOOK
LIKE BETTER PRECIP CHANCES WILL RESULT FROM THE SHIFT AND SUBSEQUENT
COLD FRONTAL PASSAGE...TIMING OF THAT IS ALSO UNCERTAIN...BUT SUN
NIGHT INTO MON LOOKS LIKE BEST BET FOR NOW. WIDESPREAD PRECIP STILL
MAY NOT OCCUR ALONG THE STRONGER WAVE AND COLD FRONTAL PASSAGE.
TEMPS LOOK TO DROP TO BELOW NORMAL VALUES MON THROUGH WED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 803 PM EDT WED JUL 29 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WHILE GUSTY W TO WSW
WINDS WILL SUBSIDE THIS EVENING AT KIWD/KSAW...EXPECT GUSTS TO
AROUND 25KT TO CONTINUE THRU THE NIGHT AT THE MORE EXPOSED KCMX
SITE. AFTER SUNRISE AND ONSET OF DAYTIME HEATING...GUSTY WINDS TO 20-
25KT WILL RETURN TO KIWD/KSAW...AND GUSTS WILL INCREASE TO AROUND
30KT AT KCMX. THERE MAY BE ISOLD SHRA NEAR KIWD THU AFTN...BUT
POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE IS TOO LOW TO INCLUDE
ANY MENTION IN FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HHUDSONBAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE
WEST-NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
330 AM EDT THU JUL 30 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 330 AM EDT THU JUL 30 2015
PLEASANT SUMMER WEATHER IS IN STORE OVER THE NEXT FEW DAYS WITH
COMFORTABLE TEMPERATURES AND HUMIDITY LEVELS ALONG WITH PLENTY OF
SUNSHINE AND FRESH WESTERLY BREEZES.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SFC DEW POINTS IN THE 50S HAVE PUSHED INTO SW LWR MI SETTING THE
STAGE FOR SOME STELLAR SUMMER WEATHER THROUGH SATURDAY. HOWEVER
WINDS WILL BE GUSTY IN THE AFTERNOONS WHEN DEEP MIXING AND DRY AIR
MASS LEADS TO EFFICIENT MOMENTUM TRANSFER OF STRONGER 25-30 KTS
WINDS AT 3000-5000 FT.
OCCASIONAL FAST MOVING SHORTWAVES DIVING SOUTHEAST THROUGH THE
NORTHERN GRTLKS REGION AND ASSOCIATED WEAK SFC TROUGHS MAY SUPPORT A
SLIGHT CHANCE OF A SHOWER OR TSTM BOTH FRIDAY OR SATURDAY. HOWEVER
THE BIG LIMITING FACTOR WILL BE THE MODERATE WESTERLY FLOW OFF LK MI
SENDING STABLE AIR WELL INLAND AND PREVENTING ANY DECENT LOW LEVEL
CONVERGENCE. TYPICALLY THIS KEEPS THE BULK OF SW LWR MI DRY WITH A
LOW POTENTIAL USUALLY LIMITED TO JUST THE NORTHEAST CORNER OF
THE CWFA AROUND CLARE.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SEASONABLE TEMPERATURES ARE ANTICIPATED SATURDAY NIGHT THROUGH
SUNDAY. THERE IS A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS LATE
SATURDAY NIGHT AND SUNDAY WITH A POTENTIALLY BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE SUNDAY NIGHT OR MONDAY WITH A
STRONGER COLD FRONT AND AS THE LONGWAVE UPPER LEVEL TROUGH BECOMES
MORE AMPLIFIED OVER THE GREAT LAKES REGION.
THE EVOLUTION OF THE UPPER LEVEL PATTERN FEATURING A RIDGE OUT WEST
AND TROUGH OVER THE EAST SUGGESTS THAT TEMPS FOR THE EARLY TO MIDDLE
PORTION OF NEXT WEEK WILL LIKELY AVERAGE A LITTLE BELOW NORMAL WITH
A CONTINUED CHC FOR A FEW SHOWERS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1227 AM EDT THU JUL 30 2015
VFR CONDITIONS ARE ANTICIPATED THROUGH THE NEXT 24 HOURS WITH
MOSTLY CLEAR SKIES. WEST WINDS WILL INCREASE TO SUSTAINED AT 15
KTS WITH GUSTS TO 25 KTS FROM LATE THURSDAY MORNING THROUGH
THURSDAY AFTERNOON BEFORE SUBSIDING THURSDAY EVENING.
&&
.MARINE...
ISSUED AT 330 AM EDT THU JUL 30 2015
WE ARE STILL LOOKING AT A BORDERLINE SMALL CRAFT ADVISORY/BEACH
HAZARD STATEMENT TODAY. THE LATEST RUC WIND GUIDANCE HAS THE
STRONGEST WINDS OVER LK MI OCCURRING THIS MORNING... OUT OF THE WEST-
NORTHWEST... THEN DECREASING AFTER THAT WHILE BACKING TO THE
SOUTHWEST.
THE IDEA IS THAT ONCE THE STRONGER HEATING AND DEEPER MIXING
COMMENCES OVER THE LAND AREAS THIS AFTERNOON WE END UP SEEING A
REVERSAL IN THE LAND/LAKE PRESSURE GRADIENT AND WIND REGIME LEADING
TO A DECREASING TREND OVER THE WATER.
LATEST BUOY OBSERVATIONS SHOW SOLID 3 FOOTERS OCCURRING AT 3 AM AND
WAVE MODEL GUIDANCE SUGGESTS A BRIEF SPIKE TO AROUND 4 FEET BETWEEN
ABOUT 6 AM AND NOON. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS AND
POST HEADLINES IF BUOY WAVE HEIGHTS CONTINUE TO TREND UP.
&&
.HYDROLOGY...
ISSUED AT 1151 AM EDT WED JUL 29 2015
RIVER LEVELS ARE FALLING AND WELL BELOW BANKFULL. THE MAIN CHANCE OF
RAIN IN THE NEXT 7 DAYS WOULD BE SUNDAY INTO MONDAY NIGHT. LOCALLY
HEAVY RAIN IS POSSIBLE... BUT ONLY PONDING OF WATER IS EXPECTED AWAY
FROM THE RIVERS. RIVERS MAY SHOW RISES... BUT SHOULD NOT REACH BANK
FULL LEVELS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...LAURENS
AVIATION...LAURENS
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
315 AM CDT THU JUL 30 2015
.SHORT TERM: (THROUGH THIS AFTERNOON)
ISSUED AT 314 AM CDT THU JUL 30 2015
"COLD" FRONT IS NOW ALMOST ALL THE WAY THROUGH THE CWFA. TOUGH TO
REALLY PICK IT OUT, BUT EVEN FARMINGTON IS REPORTING NORTHWESTERLY
WINDS AT THIS HOUR. IT MIGHT BE HUNG UP OVER THE FAR SOUTHERN
PORTIONS OF IRON AND REYNOLDS THOUGH. REGARDLESS, WE`RE AT PEAK
HEATING RIGHT NOW, AND WE CAN`T SEEM TO CRACK 105 DEGREES ON THE
HEAT INDEX, SO WILL BE DROPPING THE EXCESSIVE HEAT WARNING AT 400
PM. WIDELY SCATTERED CONVECTION IS FIRING ALONG THE FRONT, BUT IN
SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS, BUT A WEAK CAP HAS
DEVELOPED OVER THE AREA ACCORDING TO RAP SOUNDINGS SO I DON`T EXPECT
ANY CONVECTION FOR THE REST OF THE DAY AND EVENING HOURS EXCEPT
POTENTIALLY IN THE VICINITY OF THE FRONT. ANY STORMS THAT DO AFFECT
OUR SOUTHERN CWFA SHOULD BE OUT OF THE AREA OR DISSIPATED BY EARLY
EVENING. SLIGHTLY COOLER, BUT SUBSTANTIALLY DRIER AIR WILL FILTER
SOUTH OVERNIGHT. STUCK CLOSE TO ENSEMBLE GUIDANCE FOR LOWS TONIGHT
WHICH ARE ACTUALLY A LITTLE WARMER THAN OPERATIONAL MET/MAV. WANTED
TO BE A LITTLE MORE CONSERVATIVE ON THE "COOL DOWN" SINCE IT IS JULY
AFTER ALL, AND THIS ISN`T EXACTLY AN ARCTIC FRONT.
TRUETT
.LONG TERM: (TONIGHT THROUGH WEDNESDAY)
ISSUED AT 314 AM CDT THU JUL 30 2015
THE SFC RIDGE BUILDING INTO THE REGION TODAY WILL ALREADY BE S OF
THE AREA BY MID-DAY FRI. THIS WILL RETURN THE REGION TO SWLY FLOW
BRIEFLY AHEAD OF THE NEXT CDFNT. HAVE TRENDED SLIGHTLY WARMER FRI
OVER TEMPS FOR TODAY BECAUSE OF THIS. FORCING ASSOCIATED WITH THIS
FNT IS RATHER WEAK WITH NWLY 850MB FLOW AHEAD OF THE FNT. THEREFORE,
DO NOT ANTICIPATE MUCH IN THE WAY OF CONVECTION WITH THIS FNT.
HOWEVER, WITH WARM TEMPS AND DEWPOINT POOLING ALONG/AHEAD OF THE
FNT, A FEW TSRA ARE POSSIBLE. PRECIP CHANCES ARE BETTER WITH THE
NEXT CDFNT SAT NIGHT INTO SUN AND POSSIBLY INTO NEXT WEEK.
WHILE MDLS ARE IN FAIRLY GOOD AGREEMENT THRU SAT, DIFFERENCES
GREATLY INCREASE IN THE EXTD. HAVE THEREFORE KEPT POPS LOWER DUE TO
THE UNCERTAINTY. KEPT TEMPS TRENDING SLIGHTLY WARMER THAN A
COMPROMISE AMONG MDL GUIDANCE.
TILLY
&&
.AVIATION: (FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 508 PM CDT WED JUL 29 2015
COLD FRONT HAS M0VED THROUGH THE AREA WITH HIGH PRESSURE SETTLING
IN FROM THE NORTHERN ROCIKES TO THE LOWER MISSOURI VALLEY. DEW
POINTS IN THE 60S WILL BE A WELCOME CHANGE. LIGHT WEST TO
NORTHWEST WIND AND VFR CONDITIONS.
SPECIFICS FOR KSTL: HIGH PRESSURE MOVING WITH DRIER AIR. LIGHT
WEST TO NORTHWEST WIND THROUGH THURSDAY. VFR.
JPK
&&
.PRELIMINARY POINT TEMPS/POPS:
SAINT LOUIS 90 69 91 69 / 0 0 10 20
QUINCY 88 65 89 64 / 0 0 20 20
COLUMBIA 89 66 90 66 / 5 0 10 20
JEFFERSON CITY 90 66 91 67 / 5 0 10 20
SALEM 88 66 89 66 / 0 0 10 20
FARMINGTON 87 63 89 67 / 5 0 5 10
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1143 PM CDT WED JUL 29 2015
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 249 PM CDT WED JUL 29 2015
FORECAST CONCERNS IN THE VERY SHORT TERM WILL BE ANY LIGHT
SPRINKLES IN SOUTHEAST NEBRASKA...THEN TEMPERATURES...AND CHANCE
OF THUNDERSTORMS FRIDAY INTO SATURDAY.
WATER VAPOR SATELLITE IMAGERY SHOWED THE MAIN SYNOPTIC FEATURE OF
INTEREST WAS THE CLOSED LOW PRESSURE CENTER OVER ONTARIO CANADA
WITH THE MID LEVEL MOISTURE PLUME FROM THE BAJA OF CALIFORNIA
THROUGH THE FOUR CORNERS REGION INTO THE CENTRAL PLAINS AND OHIO
RIVER VALLEY. OF NOTE ON THE H3 MAP WAS THE H3 JET OVER THE
NORTHERN/CENTRAL PLAINS INTO THE GREAT LAKES. AT H5...THE
STRONGEST HEIGHT FALLS WERE ASSOCIATED WITH THE CLOSED LOW IN
CANADA AND THESE TRAILED SOUTHWARD INTO THE PLAINS. MID LEVEL
MOISTURE WAS NOTED AT H5 AT KLBF ON THEIR 12Z SOUNDING. THE BETTER
H7 AND H85 MOISTURE WAS SUPPRESSED TO THE SOUTH ACROSS KANSAS.H85
DEWPOINTS OF 14-16 DEG C FROM NEW MEXICO INTO TX/OK/SOUTHERN KS.
THERE IS A POCKET OF WEAK WARM AIR ADVECTION/WEAKENING H85-H7
FRONTOGENESIS WITH PATCHY MID LEVEL CUMULUS AND A FEW
SPRINKLES. ALSO HAVE SOME WEAK RIGHT ENTRANCE JET LIFT. HAVE
ADDED SOME SPRINKLES WITH THESE FEATURES. MOST OF THE MODELS WERE
DRY...HOWEVER THE HRRR AND THE HRRRX DID HINT AT THIS IN THEIR
ASSIMILATED REFLECTIVITY FIELDS. SURFACE HIGH PRESSURE PREVAILS
FOR THE REST OF TONIGHT INTO THURSDAY. LOWS TONIGHT IN THE UPPER
50S TO LOWER 60S. HIGH THURSDAY SHOULD TOP OUT IN THE UPPER 80S TO
LOWER 90S.
DEEPER MOISTURE RETURNS THURSDAY NIGHT AND FRIDAY WITH A WEST TO
EAST INSTABILITY AXIS DEVELOPING AND MOISTURE POOLING ALONG THIS
AXIS. WE ARE IN NORTHWEST LOW ALOFT AND THE FORCING IS WEAK.
INSTABILITY DOES INCREASE TO 2000 J/KG THURSDAY NIGHT AND 4000
J/KG FRIDAY. DO MENTION ISOLATED TO SCATTERED THUNDERSTORMS
FRIDAY AND SATURDAY WITH WEAK FORCING IN THIS PATTERN. HIGH
TEMPERATURES CONTINUE IN THE MID TO UPPER 80S EACH DAY.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 249 PM CDT WED JUL 29 2015
THE UNSETTLED PATTERN CONTINUES IN THE EXTENDED AS RIDGE AMPLIFIES
TO THE WEST WITH THE MID TROPOSPHERIC TROF TO OUR EAST AND WE
REMAIN IN NORTHWEST FLOW ALOFT. THE EC TRIES TO BRING A DEEPER
WAVE ACROSS THE ROCKIES INTO THE PLAINS MONDAY NIGHT AND TUESDAY
WITH MORE ROBUST PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1142 PM CDT WED JUL 29 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD ALONG WITH
SOUTHWESTERLY SFC WINDS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
148 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION LATE TONIGHT INTO
TOMORROW MORNING BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS
ACROSS THE REGION. FRIDAY IS EXPECTED TO BE SLIGHTLY COOLER AND
DRIER.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
940 PM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MADE MINOR
OVERNIGHT TEMPERATURE ADJUSTMENTS. SFC COLD FRONT CURRENTLY
BETWEEN DETROIT AND CLEVELAND WITH WEAK CONVECTION OVER EASTERN
OHIO. LATEST HRRR INDICATES CONVECTION ASSOCIATED WITH THIS
BOUNDARY WILL MOVE INTO THE WESTERN CWA AROUND 12Z THEN REACH THE
CENTRAL PTN OF THE FA INCLUDING BGM AROUND 15Z, THIS TIMING
MATCHES WELL WITH CURRENT POP FORECAST.
300 PM EDT UPDATE...
ANOTHER NICE SUMMER DAY IS PRESENT OVER CENTRAL NY AND NORTHEAST PA
THIS AFTERNOON. CIRRUS CLOUDS ARE OVERSPREADING THE REGION AS
MOISTURE IS ROUNDING THE OUTER EDGE OF THE UPPR RIDGE. A CU MID LVL
DECK IS DEVELOPING AS WELL DUE TO DIURNAL HEATING AND SOME LINGERING
MOISTURE. 850MB TEMPS WILL RISE TO NEAR 20 DEGREES C... WHICH SHOULD
RESULT TEMPS REACHING THE UPPR 80S TO LOW 90S WITH NO PROBLEM.
CLOUD COVERAGE WILL INCREASE OVERNIGHT WITH THE APPROACHING UPPR LVL
TROUGH AS IT ADVECTS MORE MOISTURE INTO THE REGION. THE WAA WILL
KEEP TEMPS WELL ABOVE SEASONAL AVERAGE IN THE 70S OVERNIGHT.
THE MENTIONED UPPR LVL TROUGH WILL BRING A COLD FRONT ACROSS THE
REGION STARTING LATE TONIGHT/NEAR SUNRISE TIME FRAME. THIS FRONT IS
FAIRLY WEAK AS VERY LITTLE CHANGES IN THE 1000-500MB HEIGHT
THICKNESS WILL OCCUR. PWAT VALUES WILL BE FAIRLY HEIGHT TOMORROW...
NEAR 2 INCHES. WITH THIS ENVIRONMENT... EXPECT SOME HEAVY RAIN
SHOWERS AS THIS FRONT PASSES. EMBEDDED THUNDER WILL BE POSSIBLE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
300 PM EDT UPDATE...
THE COLD FRONT IS EXPECTED TO MOVE EAST AND REACH I-81 ROUGHLY
AROUND 18Z TOMORROW... THEN BE EAST OUT OF THE REGION BY 00Z FRIDAY.
SHOWERS AND THUNDERSTORMS ARE LIKELY ALONG AND AHEAD OF THE COLD
FRONT. DEPENDING ON HOW QUICKLY THE FRONT MOVES THROUGH THE CWA WILL
DEPEND ON HOW STRONG THUNDERSTORMS MAY BECOME. THE SLOWER THE FRONT
MOVES THROUGH THE AREA THE MORE UNSTABLE THE ATMOSPHERE WILL BE ABLE
TO BECOME. SBCAPE AT BEST MAY BE AROUND 1800 J/KG... LOW LVL LAPSE
RATES WILL BE ROUGHLY 6.5 C/KM... MID LVL LAPSE RATES WILL BE ON THE
WEAK SIDE NEAR 5 C/KM... AND 0-6-KM BULK SHEAR VALUES WILL BE ON THE
LOW SIDE RANGING 15-25 KNOTS. PWAT VALUES WILL BE HIGH... AROUND 2
INCHES. FROM THE STATED PARAMETERS ABOVE... EXPECT MOSTLY HEAVY
SHOWERS AND THUNDERSTORMS TO DEVELOP TOMORROW AFTERNOON. A FEW
THUNDERSTORMS MAY BE ABLE TO PRODUCE A FEW GUSTY WINDS... BUT HEAVY
RAIN IS EXPECTED TO BE THE MAIN THREAT.
BEHIND THE FROPA EXPECT CLOUD COVERAGE TO DISSIPATE FAIRLY QUICKLY
AS DRY AIR WILL FOLLOW. EXPECT BY 03Z SKIES SHOULD BECOME MOSTLY
CLEAR... AND TEMPS WILL RETURN TO MORE OF A SEASONAL AVERAGE FOR
THIS TIME OF THE YEAR IN THE LOW TO MID 60S.
FRIDAY WILL BE FAIRLY QUIET AS WEAK HIGH PRESSURE DEVELOPS IN THE
WAKE OF THE TROUGH. THIS WILL BE SHORT LIVED AS THE NEXT SYSTEM TO
IMPACT THE REGION IS EXPECTED TO MOVE THROUGH STARTING EARLY SAT
MORNING. IT LOOKS LIKE SCATTERED SHOWERS AND THUNDERSTORMS MAY BE
POSSIBLE THROUGH THE DAY ON SAT AS A WEAK FRONT/SFC TROUGH MOVES
THROUGH.
TEMPS ARE EXPECTED TO BE AT OR SLIGHTLY ABOVE THE SEASONAL AVERAGE
THROUGH THE FORECAST PERIOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
2 PM UPDATE...
FOLLOWED LATEST WPC GUIDANCE. TEMPERATURES NEAR NORMAL. UNSETTLED
BUT ONLY LOW CHC TO SCHC POPS. MODELS DO NOT AGREE ON TIMING OF
WEAK SYSTEMS MOVING THROUGH. AT UPPER LEVELS A BROAD TROUGH. THE
BEST CHANCE LOOKS LIKE MONDAY OR TUESDAY WITH A DECENT COLD FRONT
FOR EARLY AUGUST.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
SITES CURRENTLY VFR HOWEVER OVERNIGHT CLOUDS INCREASE AHEAD OF AN
APPROACHING FRONT. ALSO, AS MOISTURE IS DRAWN UP AHEAD OF THIS
FRONT IN THE LOW LEVELS WE EXPECT A STRATUS DECK TO FORM BY
MORNING AND AFFECT AVP/BGM/ELM WITH MVFR CIGS. THE ACTUAL FRONT
ITSELF WILL MOVE ACROSS THE AREA WEST TO EAST THURSDAY MORNING
BRINGING A PERIOD OF SHOWERS TO THE TAF SITES. THERE IS THE RISK
OF THUNDER AS WELL HOWEVER DUE TO THE MORNING TIMING OF THE FRONT
THE CHANCES OF THIS OCCURRING IS NOT HIGH ENOUGH TO WARRANT
INCLUSION IN TAFS. THE FRONT CLEARS ALL TAF SITES BY EARLY TO MID
AFTERNOON WITH CIGS IMPROVING TO VFR.
WINDS WILL BE S TO SW OVERNIGHT UNDER 10 KNOTS AND W-NW 10-12
KNOTS WITH GUSTS 15-20 KNOTS HIGHER TERRAIN SITES BY THU PM.
.OUTLOOK...
THURSDAY NGT TO MONDAY...MAINLY VFR. POSSIBLY BRIEF MVFR IN
SHOWERS. ALSO RESTRICTIONS IN MORNING VALLEY FOG AT KELM POSSIBLE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KAH
NEAR TERM...KAH/RRM
SHORT TERM...KAH
LONG TERM...TAC
AVIATION...PCF
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1136 PM CDT WED JUL 29 2015
.UPDATE...
ISSUED AT 1131 PM CDT WED JUL 29 2015
WEAK SHORT WAVE OVER S CENTRAL SASK GENERATING A FEW TSRA. CURRENT
SPC HRRR PROPAGATES CONVECTION ESE OVERNIGHT AND GENERALLY
DISSIPATES ANY PCPN BEFORE GETTING TOO FAR INTO THE FAR NW PORTION
OF OUR FA AROUND 12Z. KEPT FORECAST DRY THIS AREA BUT WORTH
MONITORING.
UPDATE ISSUED AT 949 PM CDT WED JUL 29 2015
NO CHANGES NECESSARY.
UPDATE ISSUED AT 639 PM CDT WED JUL 29 2015
HAVE CANCELLED WIND ADVISORY AS WINDS HAVE DROPPED BELOW ADVISORY
THRESHOLDS AND WILL CONTINUE TO DO SO THROUGH THE EVENING.
OTHERWISE NO CHANGES TO CURRENT FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 256 PM CDT WED JUL 29 2015
FORECAST CHALLENGE WILL BE HOW FAST THE GUSTY NORTHWEST WINDS DIE
OFF THIS EVENING...THEN TURNS TO THE POTENTIAL FOR ANY AFTERNOON
CONVECTION THE NEXT FEW DAYS. AS FOR THIS AFTERNOON...WINDS WERE
STILL QUITE GUSTY EVERYWHERE BUT THE STRONGEST WINDS WERE ACROSS
THE NORTHERN FA. CURRENT WIND ADVISORY SET TO EXPIRE AT 7 PM AND
WILL LET THAT RIDE AS IS. SOME CUMULUS DID FORM THIS AFTERNOON BUT
IT SHOULD THIN OUT AGAIN THIS EVENING. PATTERN IS PRETTY SIMILAR
THE NEXT THREE DAYS WITH NORTHWEST FLOW ALOFT. EACH OF THESE DAYS
THE MODELS SHOW WEAK WAVES DROPPING THRU POTENTIALLY DURING PEAK
HEATING...WHICH COULD SET OFF A FEW SHOWERS OR TSTMS. FOR THU
AFTERNOON THIS WOULD POTENTIALLY BE AROUND THE LAKE OF THE WOODS.
WENT AHEAD AND MATCHED KDLH WITH SOME ISOLATED CHANCES FOR
SHOWERS/TSTMS...ALTHOUGH CONFIDENCE IS QUITE LOW.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 256 PM CDT WED JUL 29 2015
SAME STORY GOES FOR FRI...WITH THE POTENTIAL AREA STILL BEING
AROUND THE LAKE OF THE WOODS. CONFIDENCE ALSO LOW SO DID NOT
MENTION AT THIS POINT. FOR SAT MODELS ALL OVER THE PLACE BUT
CONSISTENT IN MINIMAL IF ANY PCPN. BROADBRUSHED AN ISOLATED
MENTION BUT AGAIN CONFIDENCE LOW.
FOR SUNDAY-WEDNESDAY...MODELS IN AGREEMENT DEPICTING NORTHWEST
FLOW ALOFT. MUCH OF THIS PERIOD SHOULD BE DRY WITH SFC HIGH
PRESSURE IN CONTROL...ALTHOUGH HARD TO FORECAST WEAK WAVES WITH
THIS UPPER FLOW PATTERN. AT ANY RATE...NOT EXPECTING ANY
SIGNIFICANT WEATHER. TEMPERATURES GENERALLY NEAR NORMAL VALUES. BY
THE MIDDLE OR END OF NEXT WEEK THERE IS POTENTIAL TO GET BACK INTO
ZONAL/SW FLOW ALOFT...ALTHOUGH CONFIDENCE IN THIS POTENTIAL
PATTERN CHANGE IS STILL LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1131 PM CDT WED JUL 29 2015
MAY SEE SOME BRIEF MID LEVEL CIGS ACROSS DVL-GFK ASSOCIATED WITH
WEAKENING SHORT WAVE CURRENTLY OVER S CENTRAL SASK OTHERWISE NO
CIGS ANTICIPATED. WINDS WILL INCREASE IN THE AM BUT NOT NEAR AS
STRONG AS LAST TWO DAYS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...GODON
LONG TERM...GODON/TG
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
506 AM EDT THU JUL 30 2015
.SYNOPSIS...
SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WILL ACCOMPANY A COLD
FRONT FROM THE WESTERN ALLEGHENIES INTO THE CENTRAL RIDGE AND
VALLEY REGION EARLY TODAY...WITH ISOLATED STRONG TO SEVERE STORMS
POSSIBLE THIS AFTERNOON IN SOUTHEASTERN PENNSYLVANIA. A NOTICEABLY
DRIER AND LESS HUMID AIRMASS WILL OVERSPREAD THE AREA BEHIND THE
FRONT ON FRIDAY...WITH SEASONAL TEMPERATURES AND COMFORTABLE
HUMIDITY LEVELS TO CLOSE OUT THE MONTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR LOOP SHOWS A FRACTURED LINE/AXIS OF SHOWERS AND A FEW
EMBEDDED TSTMS MOVING INTO THE ALLEGHENIES EARLY THIS MORNING IN
ADVANCE OF SFC COLD FRONT. THE LATEST HRRR SHOWS THE FRONTAL PCPN
BAND REACHING A LINE FROM WELLSBORO TO STATE COLLEGE TO BEDFORD
BY 13Z.
A VERY MOIST AIRMASS WILL RESIDE AHEAD OF THE FRONT WITH 70+F
DEWPOINTS AND NARROW CORRIDOR OF PW VALUES AROUND 2.00 INCHES OR
+2SD ABOVE THE MEAN. THIS WILL HELP SUPPORT THE POTENTIAL FOR SOME
LOCALLY HEAVY DOWNPOURS...ESPECIALLY LATER THIS MORNING AND INTO
THE EARLY-MID AFTERNOON HOURS ACROSS PARTS OF THE ERN CWA WHERE
STRONGER INSTABILITY IS EXPECTED TO DEVELOP. THAT BEING SAID...SFC
HEATING MAY BE LIMITED AHEAD OF THE FRONT DUE TO CLOUDS/PCPN. THIS
WILL HAVE IMPLICATIONS FOR SEVERE WX POTENTIAL ACROSS ERN/SERN PA
WITH A CONDITIONAL/MARGINAL RISK TIED TO DEGREE OF DESTABILIZATION.
ALTHOUGH THE BEST LARGE-SCALE FORCING/HEIGHT FALLS AND BULK SHEAR
WILL BE DISPLACED TO THE NORTH FROM NY INTO THE NEW ENGLAND...A
FEW LOCALLY STRONG TO PERHAPS DAMAGING WIND GUSTS CANNOT BE RULED
OUT OVER THE ERN 1/3 OF THE CWA WHERE SPC HAS MAINTAINED A MRGL
RISK. SCT STORMS SHOULD PUSH EAST AND EXIT THE SE ZONES AROUND
5PM/21Z WITH A PLEASANT EVENING IN STORE FOR THE AREA.
MAX TEMPS WILL TOP OUT AROUND 90F ACROSS THE MID TO LOWER SUSQ
VALLEY...WITH HEAT INDEX VALUES APPROACHING 100F FOR A SHORT
DURATION. RELIEF FROM THE HEAT/HUMIDITY WILL ARRIVE BY TONIGHT AS
A NOTICEABLY DRIER LOW PW AIRMASS OVERSPREADS THE AREA FROM WEST
TO EAST BEHIND THE COLD FRONTAL PASSAGE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
FAIR WEATHER WITH PLENTY OF SUNSHINE...SEASONAL TEMPERATURES AND
COMFORTABLE HUMIDITY IS EXPECTED ON FRIDAY. STRONGER NW FLOW ALOFT
WILL EXTEND FROM THE NORTHERN PLAINS THROUGH THE GREAT LAKES INTO
THE WEEKEND...IN BETWEEN AN EXPANSIVE UPPER LEVEL RIDGE OVER THE
SOUTHERN ROCKIES/PLAINS AND UPPER TROUGH/CLOSED LOW INVOF HUDSON
BAY. THE FIRST...IN WHAT WILL BE A SERIES OF MOISTURE STARVED NRN
STREAM COLD FRONTS...WILL MOVE INTO THE AREA ON SATURDAY AND BRING
THE RISK OF SCT SHOWERS/ISOLATED TSTMS. MODEL CONSENSUS FAVORS NW
AND N-CENTRAL PA WITH THE HIGHEST POPS /30-40 PCT/ FOR DAY 3/SAT.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LITTLE CHANGE IS ANTICIPATED IN WHAT SHOULD BE A STABLE LARGE
SCALE FLOW PATTERN ACROSS THE CONUS DURING THE FIRST WEEK OF
AUGUST. UPPER RIDGE WILL CONTINUE TO DOMINATE OUT WEST WHILE A
BROAD UPPER TROUGH EXTENDS SWD FROM EASTERN CANADA ACROSS THE ERN
U.S. TEMPERATURES SHOULD AVG NEAR NORMAL INTO EARLY NEXT WEEK
BEFORE TRENDING COOLER LATER IN THE WEEK. CONFIDENCE IS LOW ON
TIMING OF PCPN CHANCES ASSOCD WITH NRN STREAM FRONTAL SYSTEMS.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
WIDESPREAD VFR WILL GIVE WAY TO INCREASING CLOUDS AND THE
DEVELOPMENT OF SOME HAZE/THIN FOG. MOST TERMINALS WILL SEE VIZ
SLIP TO 2-4 MILES IN THE HOURS AFTER MIDNIGHT WITH SOME LOW CLOUDS
LIKELY ADVECTING NORTH INTO SOUTH-CENTRAL AREAS IN THE VERY HUMID
TROPICAL AIRMASS.
BY MORNING...SHOWERS AND SCATTERED THUNDERSTORMS WILL BEGIN
MOVING INTO WESTERN AREAS AHEAD OF A COLD FRONT. THE FRONT WILL BE
MOVING THROUGH EASTERN PA BY EARLY TO MID AFTERNOON SO
SHOWERS/STORMS WILL NOT BE AN ALL DAY EVENT AT AREA AIRPORTS.
DRIER CONDITIONS WILL DEVELOP WEST TO EAST IN THE WAKE OF THE
FRONT.
OUTLOOK...
FRI...MAINLY VFR.
SAT...MAINLY VFR...SCATTERED SHOWERS/THUNDERSTORMS.
SUN...MAINLY VFR.
MON...MAINLY VFR...SCATTERED SHOWERS/THUNDERSTORMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
351 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
AT KCLT...THE PRIMARY FORECAST CHALLENGE WILL BE THE TIMING OF A
SWEEPING COLD FRONT AND ASSOCIATED WIND SHIFT. AT 6Z...THE COLD
FRONT WAS ANALYZED OVER THE WESTERN OHIO RIVER VALLEY. THE COLD
FRONT IS FORECAST TO SWEEP EAST TODAY...REACHING THE NC PIEDMONT
LATE THIS AFTERNOON. I WILL FORECAST LIGHT SW WINDS ACROSS THE CLT
TERMINAL THROUGH THE EARLY AFTERNOON HOURS...VEERING NW BY 22Z. A
BROKEN BAND OF SHRA/TSRA WILL LIKELY FORM AHEAD OF THE
FRONT...TRACKING SE. BASED ON THE 0Z NAM...THE MOST LIKELY TIME
WINDOW FOR CONVECTION SHOULD OCCUR BETWEEN 17Z TO 21Z...HIGHLIGHTED
WITH A PROB30.
ELSEWHERE...ALL TERMINALS RECEIVED SOME RAINFALL WEDNESDAY AFTERNOON
AND EVENING. TEMPERATURES THROUGH 6Z HAVE REMAIN VERY MILD...KEEPING
DEWPOINT DEPRESSIONS 2 DEGREES OR MORE. HOWEVER...TEMPERATURES
SHOULD CLOSE IN ON CROSSOVER VALUES BY SUNRISE...SUPPORTING A
MENTION OF FOG. I WILL INCLUDE A TEMPO GROUP FOR EACH TERMINAL FOR
DAYBREAK FOG...THICKEST AT KAVL AND KHKY. AFTER SUNRISE...THE
FORECAST CONCERN WILL SHIFT TO THE PASSAGE OF THE COLD FRONT. I WILL
USE A PROB30 FOR EACH SITE...INDICATING A EARLY TO MID AFTERNOON
BAND OF TSRA. AFTER THE CONVECTION...WINDS SHOULD VEER NNW AND
REMAIN THROUGH THE REST OF THE TAF PERIOD.
OUTLOOK...HIGH PRESSURE WITH BUILD IN BEHIND A PASSING COLD FRONT
LATE ON THURSDAY ALLOWING FOR GENERALLY DRY AND QUIET WEATHER
THROUGH THE WEEKEND. CHANCES FOR SHOWERS/THUNDERSTORMS AND THUS
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
08-14Z 14-20Z 20-02Z 02-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP MED 75% HIGH 100% HIGH 100% HIGH 100%
KAVL MED 65% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 93% MED 79% HIGH 100% HIGH 100%
KGMU HIGH 87% HIGH 100% HIGH 100% HIGH 100%
KAND MED 68% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1154 PM CDT WED JUL 29 2015
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION UPDATE...06Z AVIATION DISCUSSION.
SFC FRONT EXPECTED TO MOVE TO NEAR CKV BY 30/06Z AND TO PUSH E OF
CSV 30/12Z-30/14Z. AS SFC FRONT APPROACHES CSV...MVFR CEILING/FOG
FORMATION EXPECTED. MVFR FOG CKV/BNA 30/09Z-30/13Z. BUILDING RIDGING
INFLUENCES SFC/ALOFT SHOULD PROVIDE VFR/SKC CONDITIONS ALL TAF SITES
30/15Z-31/06Z.
&&
.PREV DISCUSSION.../ISSUED 731 PM CDT WED JUL 29 2015/
DISCUSSION...
SYNOPTIC COMPARISONS OF 500 MB HEIGHTS REVEAL MORE OF AN ANTI
CYCLONIC FLOW OVER TN AS COMPARED TO 24 HRS AGO WHEN THE FLOW WAS
STRAIGHT. THIS ADDED EXERTIONS IS WORKING TO IMPEDE THE
CONTINUATION OF THE CONVECTION MOVING SOUTHWARD. SO...AS SFC TEMPS
COOL DOWN...THIS TREND SHOULD CONTINUE. HRRR IS IN SUPPORT OF THE
TREND.
ONLY CHANGE TO FCST WILL BE TO ADJUST POPS SLIGHTLY ACROSS THE
NORTHWEST. HEAT ADVISORY WAS ALLOWED TO EXPIRE AT 7PM.
PREV DISCUSSION... /ISSUED 724 PM CDT WED JUL 29 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
MONITORING A LINE OF SHWRS/TSTMS APPROACHING CKV AROUND 30/00Z...BUT
WEAKENING RAPIDLY. IT LOOKS LIKE AT WORST SOME BKN MVFR CB CEILINGS/VSBYS
CKV...BUT PROBABLY MORE LIKELY VFR CEILINGS...THRU 30/01Z. IF CONVECTION
HOLDS TOGETHER LONG ENOUGH...SOME VCTS MAY BE POSSIBLE AROUND BNA 30/01Z-
30/03Z. AS CONVECTION MOVES SEWD INTO MID STATE...POST BKN/OVC AC/CI
POSSIBLE THRU 30/06Z-30/07Z CKV/BNA. SFC FRONT EXPECTED TO MOVE TO
NEAR CKV BY 30/06Z AND TO PUSH E OF CSV 30/12Z-30/14Z. AS SFC FRONT
APPROACHES CSV...MVFR CEILING/FOG FORMATION EXPECTED. MVFR FOG CKV/BNA
30/08Z-30/14Z. BUILDING RIDGING INFLUENCES SFC/ALOFT SHOULD PROVIDE
VFR/SKC CONDITIONS ALL TAF SITES 30/15Z-30/24Z.
PREV DISCUSSION.../ISSUED 329 PM CDT WED JUL 29 2015/
DISCUSSION...
HOT AND HUMID CONDITIONS CONTINUE ACROSS MIDDLE TENNESSEE THIS
AFTERNOON AS THE SHOWERS AND THUNDERSTORMS THAT MOVED THROUGH THE
AREA EARLIER THIS MORNING LEFT QUITE THE SOUPY AIR MASS IN PLACE.
FOR THIS EVENING AND TONIGHT...STILL THINK A FEW ISOLATED SHOWERS
AND THUNDERSTORMS MAY DEVELOP...BUT WILL SIDE WITH THE HRRR AS MUCH
OF THE AREA WILL REMAIN DRY. A COLD FRONT WILL PUSH ACROSS MIDDLE
TENNESSEE OVERNIGHT BRINGING MUCH DRIER AIR...A VERY NICE CHANGE
IN TIME FOR THE WEEKEND.
THURSDAY THROUGH TUESDAY...A QUIET WEATHER PATTERN CAN BE
EXPECTED...ESPECIALLY FOR THE BEGINNING OF AUGUST...AS HIGH
PRESSURE BUILDS OVER THE REGION. CONDITIONS WILL NOT BE QUITE AS
HUMID ALTHOUGH HIGHS WILL STILL REACH THE LOWER 90S IN MOST
LOCATIONS. BIGGEST DIFFERENCE WILL BE FELT WITH LOW TEMPERATURES
WITH MID TO UPPER 60S EXPECTED INSTEAD OF THE LOWER TO MID 70S.
TEMPERATURES WILL SLOWLY BEGIN TO INCREASE AFTER THE
WEEKEND...ALONG WITH HUMIDITY VALUES TOO.
BY THE MIDDLE OF NEXT WEEK...UPPER LEVEL PATTERN WILL AGAIN SHIFT
TO NORTHWEST FLOW AS THE SURFACE HIGH LOSES ITS STRONGHOLD. AS A
RESULT...THUNDERSTORM CHANCES WILL INCREASE TUESDAY NIGHT AND
LIKELY REMAIN IN THE FORECAST THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 75 90 66 90 / 30 10 0 0
CLARKSVILLE 71 88 65 89 / 40 0 0 0
CROSSVILLE 72 85 64 84 / 30 20 0 0
COLUMBIA 75 90 66 90 / 20 20 0 0
LAWRENCEBURG 74 90 66 89 / 20 20 0 0
WAVERLY 73 89 67 89 / 30 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS AMARILLO TX
406 AM CDT THU JUL 30 2015
.SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
.LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 85 67 85 68 86 / 20 20 20 30 40
BEAVER OK 86 68 87 69 88 / 30 30 30 20 30
BOISE CITY OK 84 64 86 66 85 / 40 40 30 30 30
BORGER TX 87 70 87 70 89 / 20 30 30 30 40
BOYS RANCH TX 83 65 83 66 85 / 20 30 20 30 30
CANYON TX 87 67 87 68 87 / 20 20 20 20 40
CLARENDON TX 90 70 88 70 88 / 20 20 20 30 30
DALHART TX 88 66 88 67 87 / 30 40 30 40 40
GUYMON OK 87 67 88 68 87 / 30 40 30 30 30
HEREFORD TX 85 67 87 67 89 / 20 20 30 30 30
LIPSCOMB TX 87 69 88 70 87 / 30 30 30 20 30
PAMPA TX 85 66 85 68 85 / 20 30 30 30 30
SHAMROCK TX 90 69 87 71 88 / 20 30 30 30 30
WELLINGTON TX 92 71 90 72 90 / 20 20 30 30 30
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
18/16
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
1254 AM CDT THU JUL 30 2015
DISCUSSION...
See 06Z Aviation Discussion below.
AVIATION...
Area radars and short-term models show convection has largely
diminished across the area. VFR conditions will prevail next 24
hours in return flow under persistent ridging aloft. Forecast
soundings develop a widespread cu field by late Thursday morning,
w/initial bases 4.5-7 kft agl.
PREV DISCUSSION... /ISSUED 332 PM CDT WED JUL 29 2015/
UPDATE...
Updated forecast for increased chance of thunderstorms over the
northern Permian Basin, southeast New Mexico and mountain areas.
DISCUSSION...
By mid-afternoon, showers and thunderstorms were developing along
a surface boundary entering the northern Permian Basin in an area
characterized by CAPE values ranging from 500 to 1000. Continued
development along this boundary as well as any additional outflow
boundaries that might develop is possible through early evening as
the atmosphere across the region is uncapped. Though instability
is less over the Permian Basin, will need to watch boundaries for
possible foci of development. Thunderstorms will begin to
decrease this evening with a loss of heating. Though shear is
insufficient for organized thunderstorm activity, DCAPE values are
significant, in excess of 1000. Sub-cloud evaporation will be
capable of producing strong and possibly damaging downbursts.
PREV DISCUSSION... /ISSUED 224 PM CDT WED JUL 29 2015/
DISCUSSION...As of 2:15 PM CDT Wednesday...Hot and muggy weather
continues with convection starting in the usual places...the
Davis/Guadalupe Mtns and the adjacent Plains. Convection is also
forming a little further east in Western Lea and Eddy Counties
along the thetae ridge per the HRRR and RAP13 high res models.
The persistent subtropical ridge centered over the Arklatex area
will shift west over the Central Plains as a trough deepens in the
eastern US. This might actually result in no convection in the
CWA Thursday thru Friday due to increased subsidence from the
ridge center moving overhead. Temps might not be as hot as the
previous week...but will remain above normal.
Medium range models are hinting at the possibility of convection
in the CWA over the weekend as the ridge continues to shift west
to over the four corners area. This will bring a NW flow aloft
possibly bringing convection into the area out of Northern New
Mexico.
As a trough in the EastPac moves into the Pacific NW early next
week the ridge will flatten and elongate bringing a return to
drier weather...with triple digits possible once again in the
Plains by mid week.
Strobin
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
44
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1139 AM EDT THU JUL 30 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE THROUGH OUR REGION TONIGHT, THEN
STALLS TO OUR SOUTH AND EAST. THE NEXT WEAK COLD FRONT SHOULD
CROSS OUR AREA LATE SATURDAY BEFORE STALLING OFFSHORE SUNDAY. A
FEW WEAK WAVES OF LOW PRESSURE MAY TRACK ALONG THE FRONT AND
POSSIBLY MOVE CLOSER TO OUR COAST MONDAY AS HIGH PRESSURE TRIES TO
ARRIVE. A STRONGER COLD FRONT IS THEN FORECAST TO ARRIVE DURING
TUESDAY, BEFORE ALSO STALLING NEARBY ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE APPROACHING COLD FRONT EXTENDED FROM THE FINGER LAKES ACROSS
CENTRAL PENNSYLVANIA DOWN INTO WEST VIRGINIA LATE THIS MORNING. A
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS WAS OUT AHEAD OF THE
FRONT AND IT WAS APPROACHING SCRANTON, HARRISBURG AND THE WESTERN
SUBURBS OF WASHINGTON. AS THE PRECIPITATION MOVES EASTWARD INTO
INCREASINGLY UNSTABLE AIR, THE THUNDERSTORMS SHOULD BECOME MORE
NUMEROUS AND THEY WILL LIKELY STRENGTHEN. MUCH OF OUR FORECAST
AREA REMAINS UNDER A MARGINAL RISK FOR SEVERE WEATHER FOR THIS
AFTERNOON INTO THIS EVENING.
THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THE TIMING OF THE
CONVECTIVE LINE. IT SHOULD BE INTO THE ALLENTOWN AND READING AREAS
BY 200 PM AND IT IS EXPECTED TO REACH THE INTERSTATE 95 CORRIDOR
IN OUR REGION AROUND OR SHORTLY AFTER 400 PM. THE SHOWERS AND
THUNDERSTORMS ARE ANTICIPATED TO BE NEARING THE COAST AT 600 PM.
MAXIMUM TEMPERATURES ARE FORECAST TO BE NEAR 90 DEGREES IN MUCH
OF OUR AREA. READINGS SHOULD NOT GET OUT OF THE 80S IN THE
ELEVATED TERRAIN UP NORTH AND ALONG THE IMMEDIATE COAST. DEW
POINT READINGS ARE EXPECTED TO BE MOSTLY IN THE LOWER 70S. WE WILL
CONTINUE THE EXCESSIVE HEAT WARNING FOR THE HIGHLY URBANIZED AREAS
ALONG THE INTERSTATE 95 CORRIDOR.
THE WIND SHOULD REMAIN FROM THE SOUTHWEST AROUND 6 TO 12 MPH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
THE AFOREMENTIONED COLD FRONT WILL CONTINUE ITS TREK TOWARD THE
COAST AND SHOULD MOVE OFFSHORE TONIGHT. THE SHOWERS AND
THUNDERSTORMS WILL CONTINUE INTO TONIGHT AND WILL END FROM
NORTHWEST TO SOUTHEAST AS THE FRONT PUSHES OFF THE COAST AND THEN
FURTHER OFFSHORE. AS THE FRONT PUSHES AWAY, WE WILL ALSO SEE SOME
CLEARING BEHIND IT AND AREAS TO THE NORTH AND WEST OF PHILLY WILL
BE ABLE TO COOL OFF A BIT AND DROP DOWN INTO THE LOWER TO MID 60S
OVERNIGHT. AREAS TO THE SOUTH AND EAST OF PHILLY WILL HOLD ONTO
THE CLOUD COVER A BIT LONGER AND WILL LIKELY REMAIN IN THE UPPER
60S TO LOWER 70S FOR OVERNIGHT LOWS. EVEN WITH THE CLEARING, LOW
LEVEL MOISTURE MAY HANG AROUND FOR A BIT AND PATCHY FOG WILL
REMAIN POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE SYNOPTIC SETUP IS COMPRISED OF AN UPPER-LEVEL TROUGH FROM THE
GREAT LAKES TO THE NORTHEAST FRIDAY WITH SOME AMPLIFICATION INTO
THE WEEKEND. DESPITE A WARM TO HOT AIRMASS IN PLACE, A SUBSTANTIAL
REDUCTION IN THE DEW POINTS IS EXPECTED FRIDAY AND EVEN FOR THE
WEEKEND OVERALL FOR THE CWA. A WEAK FRONT MOVES THROUGH LATE
SATURDAY WITH SOME POTENTIALLY TRICKY CONVECTIVE CHCS, THEN THE
NEXT ONE ARRIVES DURING TUESDAY BEFORE STALLING NEARBY WEDNESDAY.
THERE IS MORE UNCERTAINTY IN THE DETAILS ESPECIALLY NEXT WEEK AS
THE AMPLITUDE OF THE TROUGH AND THE POSITIONING OF FRONTAL
BOUNDARIES WILL IMPACT OUR SENSIBLE WEATHER. WE USED A MODEL BLEND
FRIDAY THROUGH SUNDAY, THEN WENT WITH MOSTLY A WPC/CONTINUITY
BLEND THEREAFTER.
FOR FRIDAY...AN INITIAL FRONT IS STALLED OFFSHORE AS IT BECOMES
TRAPPED BETWEEN A RIDGE IN THE WESTERN ATLANTIC AND A TROUGH FROM
THE GREAT LAKES TO THE NORTHEAST. ANY REMAINING FRONTAL FORCING AND
ASSOCIATED CONVECTION SHOULD REMAIN WELL OFFSHORE, MEANWHILE A
NOTICEABLE DRIER AIRMASS SETTLES INTO OUR AREA. DESPITE IT STILL
BEING WARM TO HOT ACROSS THE CWA, THE LOWER DEW POINTS WILL RESULT
IN A MUCH LESS HUMID FEEL /EVEN COOLER AT NIGHT/. THE AFOREMENTIONED
UPPER-LEVEL TROUGH AMPLIFIES SOME ESPECIALLY TO OUR NORTHWEST
THROUGH NORTHEAST, AND SOME UPSTREAM CONVECTION MAY TRY TO MAKE A
RUN AT OUR NORTHWEST ZONES VERY LATE AT NIGHT. OVERALL, THIS LOOKS
LIKE A VERY SMALL CHC PLUS WITH THE INITIAL DRIER AIRMASS IN PLACE
AND THEREFORE WE OPTED TO LEAVE THE NIGHT TIME FRAME DRY.
FOR SATURDAY AND SUNDAY...AN UPPER-LEVEL TROUGH REMAINS ACROSS THE
NORTHEAST ALTHOUGH IT MAY WEAKEN SOME SUNDAY AS A RIDGE IN THE
WESTERN ATLANTIC TRIES TO EXPAND NORTHWESTWARD. THIS KEEPS A STALLED
FRONTAL BOUNDARY OFFSHORE HOWEVER IT APPEARS THAT WEAK RIPPLES OF
ENERGY ALONG IT REMAINS TO OUR EAST. A SECONDARY FRONTAL ZONE IS
FORECAST TO MOVE THROUGH LATE SATURDAY INTO SUNDAY, AND THE GREATEST
LIFT AND SHEAR IS MOSTLY FROM NEAR OUR NORTHERN ZONES ON NORTHWARD
INTO NEW ENGLAND. THE DEW POINTS SHOULD START TO INCH BACK UPWARD
AGAIN LATER SATURDAY, HOWEVER ENOUGH DRYING MAY LIMIT MUCH
CONVECTIVE DEVELOPMENT. SOME GUIDANCE DOES INITIATE MORE CONVECTION
BY LATE SATURDAY FROM NORTHEASTERN PENNSYLVANIA TO NORTHERN NEW
JERSEY THEN SLIDES IT SOUTHEASTWARD. THERE MAY BE ENOUGH SHEAR WITH
INCREASING INSTABILITY TO ALLOW FOR A GUSTY THUNDERSTORM, HOWEVER
THIS IS DEPENDENT ON THE AIRMASS MOISTENING UP SUFFICIENTLY AS THE
UPPER-LEVEL TROUGH REMAINS IN PLACE. FOR NOW, WE CONTINUED SOME LOW
END CHC POPS ACROSS THE FAR NORTH SATURDAY AFTERNOON.
THE FRONT LOOKS TO STALL JUST OFFSHORE GIVEN WEAKER FLOW WITH A
SOUTHEASTERN EXTENT, HOWEVER SOME WEAK IMPULSES MAY TRACK ALONG IT.
IT APPEARS THAT ANY CONVECTION LEFTOVER WITH THE FRONT IS OFFSHORE,
THEREFORE WE HAVE A DRY SUNDAY. IT WILL CONTINUE TO BE WARM GIVEN A
SIMILAR PATTERN AND THE DEW POINTS WILL PROBABLY INCREASE A BIT
MAINLY SUNDAY NIGHT ACROSS THE SOUTHERN AND EASTERN AREAS.
FOR MONDAY AND TUESDAY...AS THE UPPER-LEVEL TROUGH RELOADS FROM THE
WEST, IT MAY SUPPORT WEAK IMPULSES TRAVERSING THE OFFSHORE FRONT. IF
THIS OCCURS AND WITH THE UPPER-LEVEL FLOW TURNING MORE SOUTHWESTERLY
FOR A TIME, THE FRONT MAY INCH BACK INTO OUR AREA TO HELP FOCUS SOME
CONVECTION MONDAY. THIS LOOKS WEAK OVERALL WITH THE MAIN FORCING
REMAINING MOSTLY ACROSS THE GREAT LAKES REGION MONDAY. TIED TO THIS
FORCING, ANOTHER COLD FRONT ARRIVES DURING TUESDAY WITH THE
POTENTIAL FOR SOME CONVECTION ALTHOUGH THE STRONGER SHEAR MAY AGAIN
SLIDE TO OUR NORTH. WE OPTED TO GO CLOSE TO THE 00Z WPC GUIDANCE
WHICH CARRIES POPS OF LOW END CHC OR LESS.
FOR WEDNESDAY...AS THE UPPER-LEVEL TROUGH STARTS TO WEAKEN IN THE
NORTHEAST, THE FRONTAL BOUNDARY FROM TUESDAY SHOULD SLOW OR EVEN
STALL IN OUR VICINITY. THIS COULD HELP FOCUS SOME CONVECTIVE
DEVELOPMENT ESPECIALLY DURING PEAK HEATING, WITH POSSIBLE
CONVECTIVELY INDUCED IMPULSES ARRIVING FROM THE WEST. THERE IS MUCH
MORE UNCERTAINTY THIS FAR OUT AS THE POSITIONING OF THE UPPER-LEVEL
TROUGH WILL GOVERN THE FRONTAL ZONE PLACEMENT AND SUBSEQUENT
CONVECTIVE CHCS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
SOME MVFR CEILINGS WERE LINGERING IN OUR REGION AROUND 1530Z. THE
CLOUDS WILL CONTINUE TO LIFT.
SHOWERS AND THUNDERSTORMS, ASSOCIATED WITH AN APPROACHING COLD
FRONT, ARE EXPECTED TO REACH KRDG AND KABE BETWEEN 17-18Z. THE
SHOWERS AND THUNDERSTORMS ARE FORECAST TO REACH KILG, KPHL, KPNE
AND KTTN AROUND 20Z. THEY SHOULD PUSH THROUGH KMIV AND KACY
BETWEEN 22-00Z. CLEARING IS EXPECTED TO OCCUR TONIGHT.
SOUTH TO SOUTHWEST WINDS AROUND 5 TO 10 ARE EXPECTED THROUGH TODAY,
BECOMING NORTHWEST BEHIND THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY...A CHANCE OF SOME FOG EARLY MAINLY AT KMIV AND KACY,
OTHERWISE VFR. NORTHWEST WINDS AROUND 10 KNOTS, THEN DIMINISHING TO
NEAR 5 KNOTS AT NIGHT AND BECOMING SOUTHWESTERLY.
SATURDAY...VFR OVERALL. A SHOWER OR THUNDERSTORM POSSIBLE IN THE
AFTERNOON AND EVENING MAINLY NORTH AND WEST OF KPHL. SOUTHWEST WINDS
5-10 KNOTS.
SUNDAY AND MONDAY...VFR IS ANTICIPATED.
&&
.MARINE...
A SOUTH TO SOUTHWEST FLOW OF AROUND 10 TO 15 KNOTS WITH GUSTS UP TO
20 KNOTS IS EXPECTED ON THE AREA WATERS THROUGH TONIGHT. SEAS WILL
REMAIN AROUND 2 TO 4 FEET.
A COLD FRONT WILL APPROACH FROM THE WEST AND REACH THE AREA
WATERS LATE TONIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
PRECEDE THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY THROUGH MONDAY...THE CONDITIONS ARE ANTICIPATED TO BE BELOW
SMALL CRAFT ADVISORY CRITERIA OVERALL. A LINGERING FRONT OFFSHORE
FRIDAY INTO SATURDAY, THEN ANOTHER FRONT MOVES THROUGH LATE SATURDAY
AND POSSIBLY STALLS NEARBY INTO MONDAY.
&&
.RIP CURRENTS...
A MODERATE RISK OF DANGEROUS RIP CURRENTS IS FORECAST FOR
TODAY, WITH INCREASING SOUTH TO SOUTHWEST FLOW AHEAD OF A COLD
FRONT AND THE FULL MOON ON FRIDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ070-
071-102-104-106.
NJ...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR NJZ015-
017>019.
DE...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...IOVINO/YAROSH
SHORT TERM...MEOLA
LONG TERM...GORSE
AVIATION...GORSE/MEOLA
MARINE...GORSE/MEOLA
RIP CURRENTS...MEOLA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
952 AM EDT THU JUL 30 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE THROUGH OUR REGION TONIGHT, THEN
STALLS TO OUR SOUTH AND EAST. THE NEXT WEAK COLD FRONT SHOULD
CROSS OUR AREA LATE SATURDAY BEFORE STALLING OFFSHORE SUNDAY. A
FEW WEAK WAVES OF LOW PRESSURE MAY TRACK ALONG THE FRONT AND
POSSIBLY MOVE CLOSER TO OUR COAST MONDAY AS HIGH PRESSURE TRIES TO
ARRIVE. A STRONGER COLD FRONT IS THEN FORECAST TO ARRIVE DURING
TUESDAY, BEFORE ALSO STALLING NEARBY ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ISOLATED SHOWERS WERE LINGERING IN PARTS OF CENTRAL AND SOUTHERN
NEW JERSEY AROUND 930 AM. THE LIGHT PRECIPITATION WILL CONTINUE TO
LIFT NORTHEASTWARD AND WEAKEN DURING THE BALANCE OF THE MORNING.
THE APPROACHING COLD FRONT EXTENDED ACROSS WESTERN NEW YORK AND
WESTERN PENNSYLVANIA DOWN INTO WEST VIRGINIA AT MID MORNING. A
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS WAS OUT AHEAD OF THE
FRONT AND IT EXTENDED THROUGH CENTRAL NEW YORK AND CENTRAL
PENNSYLVANIA. AS THE PRECIPITATION MOVES EASTWARD INTO
INCREASINGLY UNSTABLE AIR, THE THUNDERSTORMS SHOULD BECOME MORE
NUMEROUS AND THEY WILL LIKELY STRENGTHEN. MUCH OF OUR FORECAST
AREA REMAINS UNDER A MARGINAL RISK FOR SEVERE WEATHER FOR THIS
AFTERNOON INTO THIS EVENING.
THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THE TIMING OF THE
CONVECTIVE LINE. IT SHOULD BE INTO THE ALLENTOWN AND READING AREAS
BY 200 PM AND IT IS EXPECTED TO REACH THE INTERSTATE 95 CORRIDOR
IN OUR REGION AROUND OR SHORTLY AFTER 400 PM. THE SHOWERS AND
THUNDERSTORMS ARE ANTICIPATED TO BE NEARING THE COAST AT 600 PM.
MAXIMUM TEMPERATURES ARE FORECAST TO BE NEAR 90 DEGREES IN MUCH
OF OUR AREA. READINGS SHOULD NOT GET OUT OF THE 80S IN THE
ELEVATED TERRAIN UP NORTH AND ALONG THE IMMEDIATE COAST. DEW
POINT READINGS ARE EXPECTED TO BE MOSTLY IN THE LOWER 70S. WE WILL
CONTINUE THE EXCESSIVE HEAT WARNING FOR THE HIGHLY URBANIZED AREAS
ALONG THE INTERSTATE 95 CORRIDOR.
THE WIND SHOULD REMAIN FROM THE SOUTHWEST AROUND 6 TO 12 MPH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
THE AFOREMENTIONED COLD FRONT WILL CONTINUE ITS TREK TOWARD THE
COAST AND SHOULD MOVE OFFSHORE TONIGHT. THE SHOWERS AND
THUNDERSTORMS WILL CONTINUE INTO TONIGHT AND WILL END FROM
NORTHWEST TO SOUTHEAST AS THE FRONT PUSHES OFF THE COAST AND THEN
FURTHER OFFSHORE. AS THE FRONT PUSHES AWAY, WE WILL ALSO SEE SOME
CLEARING BEHIND IT AND AREAS TO THE NORTH AND WEST OF PHILLY WILL
BE ABLE TO COOL OFF A BIT AND DROP DOWN INTO THE LOWER TO MID 60S
OVERNIGHT. AREAS TO THE SOUTH AND EAST OF PHILLY WILL HOLD ONTO
THE CLOUD COVER A BIT LONGER AND WILL LIKELY REMAIN IN THE UPPER
60S TO LOWER 70S FOR OVERNIGHT LOWS. EVEN WITH THE CLEARING, LOW
LEVEL MOISTURE MAY HANG AROUND FOR A BIT AND PATCHY FOG WILL
REMAIN POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE SYNOPTIC SETUP IS COMPRISED OF AN UPPER-LEVEL TROUGH FROM THE
GREAT LAKES TO THE NORTHEAST FRIDAY WITH SOME AMPLIFICATION INTO
THE WEEKEND. DESPITE A WARM TO HOT AIRMASS IN PLACE, A SUBSTANTIAL
REDUCTION IN THE DEW POINTS IS EXPECTED FRIDAY AND EVEN FOR THE
WEEKEND OVERALL FOR THE CWA. A WEAK FRONT MOVES THROUGH LATE
SATURDAY WITH SOME POTENTIALLY TRICKY CONVECTIVE CHCS, THEN THE
NEXT ONE ARRIVES DURING TUESDAY BEFORE STALLING NEARBY WEDNESDAY.
THERE IS MORE UNCERTAINTY IN THE DETAILS ESPECIALLY NEXT WEEK AS
THE AMPLITUDE OF THE TROUGH AND THE POSITIONING OF FRONTAL
BOUNDARIES WILL IMPACT OUR SENSIBLE WEATHER. WE USED A MODEL BLEND
FRIDAY THROUGH SUNDAY, THEN WENT WITH MOSTLY A WPC/CONTINUITY
BLEND THEREAFTER.
FOR FRIDAY...AN INITIAL FRONT IS STALLED OFFSHORE AS IT BECOMES
TRAPPED BETWEEN A RIDGE IN THE WESTERN ATLANTIC AND A TROUGH FROM
THE GREAT LAKES TO THE NORTHEAST. ANY REMAINING FRONTAL FORCING AND
ASSOCIATED CONVECTION SHOULD REMAIN WELL OFFSHORE, MEANWHILE A
NOTICEABLE DRIER AIRMASS SETTLES INTO OUR AREA. DESPITE IT STILL
BEING WARM TO HOT ACROSS THE CWA, THE LOWER DEW POINTS WILL RESULT
IN A MUCH LESS HUMID FEEL /EVEN COOLER AT NIGHT/. THE AFOREMENTIONED
UPPER-LEVEL TROUGH AMPLIFIES SOME ESPECIALLY TO OUR NORTHWEST
THROUGH NORTHEAST, AND SOME UPSTREAM CONVECTION MAY TRY TO MAKE A
RUN AT OUR NORTHWEST ZONES VERY LATE AT NIGHT. OVERALL, THIS LOOKS
LIKE A VERY SMALL CHC PLUS WITH THE INITIAL DRIER AIRMASS IN PLACE
AND THEREFORE WE OPTED TO LEAVE THE NIGHT TIME FRAME DRY.
FOR SATURDAY AND SUNDAY...AN UPPER-LEVEL TROUGH REMAINS ACROSS THE
NORTHEAST ALTHOUGH IT MAY WEAKEN SOME SUNDAY AS A RIDGE IN THE
WESTERN ATLANTIC TRIES TO EXPAND NORTHWESTWARD. THIS KEEPS A STALLED
FRONTAL BOUNDARY OFFSHORE HOWEVER IT APPEARS THAT WEAK RIPPLES OF
ENERGY ALONG IT REMAINS TO OUR EAST. A SECONDARY FRONTAL ZONE IS
FORECAST TO MOVE THROUGH LATE SATURDAY INTO SUNDAY, AND THE GREATEST
LIFT AND SHEAR IS MOSTLY FROM NEAR OUR NORTHERN ZONES ON NORTHWARD
INTO NEW ENGLAND. THE DEW POINTS SHOULD START TO INCH BACK UPWARD
AGAIN LATER SATURDAY, HOWEVER ENOUGH DRYING MAY LIMIT MUCH
CONVECTIVE DEVELOPMENT. SOME GUIDANCE DOES INITIATE MORE CONVECTION
BY LATE SATURDAY FROM NORTHEASTERN PENNSYLVANIA TO NORTHERN NEW
JERSEY THEN SLIDES IT SOUTHEASTWARD. THERE MAY BE ENOUGH SHEAR WITH
INCREASING INSTABILITY TO ALLOW FOR A GUSTY THUNDERSTORM, HOWEVER
THIS IS DEPENDENT ON THE AIRMASS MOISTENING UP SUFFICIENTLY AS THE
UPPER-LEVEL TROUGH REMAINS IN PLACE. FOR NOW, WE CONTINUED SOME LOW
END CHC POPS ACROSS THE FAR NORTH SATURDAY AFTERNOON.
THE FRONT LOOKS TO STALL JUST OFFSHORE GIVEN WEAKER FLOW WITH A
SOUTHEASTERN EXTENT, HOWEVER SOME WEAK IMPULSES MAY TRACK ALONG IT.
IT APPEARS THAT ANY CONVECTION LEFTOVER WITH THE FRONT IS OFFSHORE,
THEREFORE WE HAVE A DRY SUNDAY. IT WILL CONTINUE TO BE WARM GIVEN A
SIMILAR PATTERN AND THE DEW POINTS WILL PROBABLY INCREASE A BIT
MAINLY SUNDAY NIGHT ACROSS THE SOUTHERN AND EASTERN AREAS.
FOR MONDAY AND TUESDAY...AS THE UPPER-LEVEL TROUGH RELOADS FROM THE
WEST, IT MAY SUPPORT WEAK IMPULSES TRAVERSING THE OFFSHORE FRONT. IF
THIS OCCURS AND WITH THE UPPER-LEVEL FLOW TURNING MORE SOUTHWESTERLY
FOR A TIME, THE FRONT MAY INCH BACK INTO OUR AREA TO HELP FOCUS SOME
CONVECTION MONDAY. THIS LOOKS WEAK OVERALL WITH THE MAIN FORCING
REMAINING MOSTLY ACROSS THE GREAT LAKES REGION MONDAY. TIED TO THIS
FORCING, ANOTHER COLD FRONT ARRIVES DURING TUESDAY WITH THE
POTENTIAL FOR SOME CONVECTION ALTHOUGH THE STRONGER SHEAR MAY AGAIN
SLIDE TO OUR NORTH. WE OPTED TO GO CLOSE TO THE 00Z WPC GUIDANCE
WHICH CARRIES POPS OF LOW END CHC OR LESS.
FOR WEDNESDAY...AS THE UPPER-LEVEL TROUGH STARTS TO WEAKEN IN THE
NORTHEAST, THE FRONTAL BOUNDARY FROM TUESDAY SHOULD SLOW OR EVEN
STALL IN OUR VICINITY. THIS COULD HELP FOCUS SOME CONVECTIVE
DEVELOPMENT ESPECIALLY DURING PEAK HEATING, WITH POSSIBLE
CONVECTIVELY INDUCED IMPULSES ARRIVING FROM THE WEST. THERE IS MUCH
MORE UNCERTAINTY THIS FAR OUT AS THE POSITIONING OF THE UPPER-LEVEL
TROUGH WILL GOVERN THE FRONTAL ZONE PLACEMENT AND SUBSEQUENT
CONVECTIVE CHCS.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
PATCHY MVFR CEILINGS WERE LINGERING IN OUR REGION AROUND 1330Z.
THE CLOUDS WILL CONTINUE TO LIFT. SCATTERED CLOUDS OR VFR CEILINGS
ARE ANTICIPATED FOR THE LATE MORNING AND EARLY AFTERNOON HOURS.
SHOWERS AND THUNDERSTORMS, ASSOCIATED WITH AN APPROACHING COLD
FRONT, ARE EXPECTED TO REACH KRDG AND KABE BETWEEN 17-18Z. THE
SHOWERS AND THUNDERSTORMS ARE FORECAST TO REACH KILG, KPHL, KPNE
AND KTTN AROUND 20Z. THEY SHOULD PUSH THROUGH KMIV AND KACY
BETWEEN 22-00Z. CLEARING IS EXPECTED TO OCCUR TONIGHT.
SOUTH TO SOUTHWEST WINDS AROUND 5 TO 10 ARE EXPECTED THROUGH TODAY,
BECOMING NORTHWEST BEHIND THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY...A CHANCE OF SOME FOG EARLY MAINLY AT KMIV AND KACY,
OTHERWISE VFR. NORTHWEST WINDS AROUND 10 KNOTS, THEN DIMINISHING TO
NEAR 5 KNOTS AT NIGHT AND BECOMING SOUTHWESTERLY.
SATURDAY...VFR OVERALL. A SHOWER OR THUNDERSTORM POSSIBLE IN THE
AFTERNOON AND EVENING MAINLY NORTH AND WEST OF KPHL. SOUTHWEST WINDS
5-10 KNOTS.
SUNDAY AND MONDAY...VFR IS ANTICIPATED.
&&
.MARINE...
A SOUTH TO SOUTHWEST FLOW OF AROUND 10 TO 15 KNOTS WITH GUSTS UP TO
20 KNOTS IS EXPECTED ON THE AREA WATERS THROUGH TONIGHT. SEAS WILL
REMAIN AROUND 2 TO 4 FEET.
A COLD FRONT WILL APPROACH FROM THE WEST AND REACH THE AREA
WATERS LATE TONIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
PRECEDE THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY THROUGH MONDAY...THE CONDITIONS ARE ANTICIPATED TO BE BELOW
SMALL CRAFT ADVISORY CRITERIA OVERALL. A LINGERING FRONT OFFSHORE
FRIDAY INTO SATURDAY, THEN ANOTHER FRONT MOVES THROUGH LATE SATURDAY
AND POSSIBLY STALLS NEARBY INTO MONDAY.
&&
.RIP CURRENTS...
A MODERATE RISK OF DANGEROUS RIP CURRENTS IS FORECAST FOR
TODAY, WITH INCREASING SOUTH TO SOUTHWEST FLOW AHEAD OF A COLD
FRONT AND THE FULL MOON ON FRIDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ070-
071-102-104-106.
NJ...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR NJZ015-
017>019.
DE...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...IOVINO/YAROSH
SHORT TERM...MEOLA
LONG TERM...GORSE
AVIATION...GORSE/MEOLA
MARINE...GORSE/MEOLA
RIP CURRENTS...MEOLA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
940 AM EDT THU JUL 30 2015
DISCUSSION...
LOW EAST OF GEORGIA/SOUTH CAROLINA WILL CONTINUE TO TRACK AWAY FROM
THE EAST COAST. UPPER LEVEL/500MB TROUGHING BETWEEN UPPER
LEVEL/500MB HIGHS OVER SOUTHERN PLAINS TO THE WEST AND EAST OF THE
BAHAMA ISLANDS EAST IN THE WESTERN ATLANTIC.
LATEST RAP FORECAST RUN SHOWS THE SURFACE LOW CONTINUING TO TRACK
SLOWLY EAST NORTHEAST THE NEXT 12 HOURS. THIS TRACK WILL MAINTAIN
THE OFFSHORE FLOW. LOCAL WRF MODELS SUGGESTING A SEA BREEZE
DEVELOPING FROM CAPE CANAVERAL NORTH WHERE THE OFFSHORE WINDS ARE
FORECAST TO BE LIGHTER. POTENTIAL FOR SOME STRONGER STORMS OVER THE
NORTH FORECAST AREA WHERE SLIGHTLY COOLER UPPER LEVEL TEMPERATURES
RESIDE AND AT THE COAST WHERE THERE MAYBE SEA BREEZE INTERACTING
WITH THE PREVAILING WESTERLY FLOW.
CHANGES TO MAINLY THE VARIOUS WIND GRIDS.
.AVIATION...
PREVAILING VFR THROUGH 18Z. TEMPO MVFR VCTS 19Z-21Z. VFR 31/00Z
THROUGH 31/08Z. TEMPO IFR/MVFR CEILINGS/VISIBILITY 31/08Z-31/14Z DUE
TO LOW CLOUDS/MIST/FOG.
.MARINE...
BUOY 009 WAS RECORDING SOUTHWEST WINDS AROUND 10 KNOTS AND 2 FOOT
SEAS. THE TWO SCRIPPS BUOYS AT 4NM AND 6NM OFF THE BEACH WERE
RECORDING 1 FOOT SEAS.
AFTERNOON SEA BREEZE CAPE CANAVERAL NORTH...OFFSHORE WINDS SOUTH OF
CAPE CANAVERAL AND REMAINDER OF COASTAL WATERS.
PREVIOUS AFD
TODAY-TONIGHT...MODELS SHOW THAT THE AREA OF LOWER PRECIPITABLE
WATER VALUES...THAT SLIPPED INTO NORTHERN AREAS YESTERDAY...
MOISTENING BACK UP ABOVE 2 INCHES. THIS SEEMS REASONABLE AS THE
PERIPHERAL DRYING FROM LOW PRESSURE SYSTEM OFFSHORE NORTH FLORIDA
LIFTS FARTHER AWAY TO THE NORTHEAST.
HAD BEEN A BIT DUBIOUS ABOUT THE 50-70 POPS ADVERTISED BY MOS
ESPECIALLY SINCE THERE WAS CONSIDERABLE DEBRIS CLOUDINESS
OVERSPREADING THE PENINSULA FROM CONVECTION OFFSHORE. RECENT
TRENDS SHOW THE CLOUDS DIMINISHING...AND AS THE LOW PULLS SLOWLY
NORTHEAST...EXPECT THIS TREND TO CONTINUE. THEREFORE MOST PLACES
SHOULD HEAT UP TO AROUND 90 OR THE LOWER 90S. THE MODELS HAVE BEEN
SHOWING TEMPS ALOFT COOLING TO AROUND MINUS 7 CELSIUS. THEREFORE
EXPECT A FEW MORE STRONG STORMS...WITH FREQUENT LIGHTNING STRIKES
BEING THE MAIN DANGER. FORECAST SOUNDINGS SHOW SOME LINGERING
DRIER AIR ALOFT...SO ISOLATED STRONG WIND GUSTS 50-60 MPH COULD
OCCUR AGAIN.
AS FAR AS DISTRIBUTION/TIMING OF THE STORMS...WOULD EXPECT A
GENERAL SCENARIO SIMILAR TO YESTERDAY WITH SHOWERS/STORMS MOVING
ACROSS SOUTHERN SECTIONS EARLIEST (WHERE THE STRONGEST/DEEPEST
WESTERLY FLOW WILL EXIST). THE LOCAL WRF AND HRRR MODELS GENERALLY
SHOW THIS OCCURRING...WITH LATER AND SLOWER MOVING STORMS EXPECTED
ACROSS THE NORTH AS BOUNDARIES INTERACT. THESE STORMS COULD BE
THE STRONGEST OF THE DAY.
MOS HAS POPS 50-60 PERCENT IN THE SOUTH TONIGHT...BUT GIVEN THE
ABOVE DISCUSSION...HAVE TRENDED BELOW THOSE UN-CLIMATOLOGICAL
VALUES.
FRI-FRI NIGHT...WEAK AREA OF LOW PRESSURE AT 500 MB LINGERS OFF OF
THE IMMEDIATE EAST FLORIDA COAST WITH MID-LEVEL HIGH PRESSURE
RIDGING EXTENDING NORTH OF THE AREA ACROSS THE GULF COAST STATES.
AT THE SURFACE HIGH PRESSURE RIDGING REMAINS SUPPRESSED ACROSS THE
SOUTHERN FL PENINSULA/FL STRAITS. A WEAK AREA OF SURFACE LOW
PRESSURE OFF OF THE CAROLINAS EARLY IN THE PERIOD WILL LIFT FAIRLY
RAPIDLY NORTHEASTWARD AWAY FROM THE AREA. DEEP LAYER MOISTURE
CONTINUES WITH PRECIPITABLE WATER VALUES IN EXCESS OF 2 INCHES
ACROSS MUCH OF THE AREA. SUBTLE IMPULSES ALOFT...DEEP MOISTURE AND
BOUNDARY INTERACTIONS THROUGH THE DAY WILL ALLOW FOR HIGH END CHANCE
POPS (50 PERCENT) NEAR I-4 CORRIDOR NORTHWARD (AFTN/EVENING) AND
LIKELY CHANCES (60-70 PERCENT) SOUTHWARD. SCHC/LOW END CHC WORDING
FOR POPS DURING THE MORNING. LOWERING RAIN CHANCES FRI NIGHT THOUGH
REALISTICALLY THERE WILL REMAIN AT LEAST A SLIGHT CHANCE ACROSS ECFL
OVERNIGHT. STORM MOVEMENT MAINLY OUT OF THE SW OR W. HIGHS IN THE
U80S TO AROUND 90 AND LOWS GENERALLY IN THE M/U 70S.
WEEKEND...SURFACE RIDGE AXIS WILL REMAIN SITUATED OVER THE SOUTHERN
FL PENINSULA AS SSW/SW FLOW CONTINUES IN THE LOW-LEVELS. ALOFT...A
GENERALLY TROUGHY PATTERN CONTINUES ALONG THE EASTERN SEABOARD TO
INCLUDE THE FLORIDA PENINSULA. WE ALSO MAINTAIN THE DEEP MOISTURE
AND RELATIVELY WARM TEMPERATURES ALOFT. THE STORM MOTION WHILE WEAK
WILL GENERALLY FAVOR A WEST TO EAST MOVEMENT. LOCALLY HEAVY
RAINFALL...GUSTY WINDS AND CLOUD TO GROUND LIGHTNING WILL REMAIN THE
MAIN CONVECTIVE THREATS. WITH THIS PERSISTENT PATTERN WILL KEEP
LOWER END SCHC/CHC POPS DURING THE MORNING AND MAINLY LIKELY (60
PERCENT) MENTION FOR THE AFTERNOON/EARLY EVENING PERIODS. HIGHS/LOWS
WILL REMAIN CONSISTENT FROM WHAT WE HAVE BEEN SEEING RECENTLY.
MON-WED...ALOFT...AS THE HIGH PRESSURE RIDGING CONTINUES TO AMPLIFY
OVER THE WESTERN U.S. THE GENERAL TROUGHINESS WILL CONTINUE ACROSS
THE EASTERN CONUS. THE SURFACE ATLANTIC RIDGE WILL BEGIN BUILDING
BACK NORTHWARD TUE-WED AS THE EASTERN CONUS LOW-LEVEL TROUGHING
SHIFTS WEST OVER THE GULF OF MEXICO. EXPECT MOISTURE TO REMAIN HIGH
AND POPS 50 PERCENT OR A LITTLE HIGHER STILL SEEM WARRANTED...EXCEPT
POSSIBLY TRENDING LOWER WED...IF THE SURFACE RIDGE DOES INDEED BUILD
BACK INTO CENTRAL FLORIDA.
&&
.AVIATION...A FEW MVFR CEILINGS WILL OCCUR UNTIL A LITTLE AFTER
SUNRISE. THERE IS A LITTLE MORE LOW LEVEL WIND THIS MORNING...BUT
LOCAL IFR COULD BRIEFLY OCCUR TOO. THEN THE MAIN FORECAST PROBLEM
BECOMES THE TIMING OF STORMS. EXPECT THAT FROM ABOUT KVRB-KSUA
THERE WILL BE A CHANCE FOR STORMS RATHER EARLY AGAIN...ABOUT
16-20Z...WITH THE REMAINING TERMINALS LIKELY HAVING THE GREATEST
CHANCE BETWEEN 18-22Z. A FEW STRONG STORMS WITH WIND FREQUENT
LIGHTNING STRIKES AND GUSTY WINDS OVER 30 KNOTS ARE EXPECTED AGAIN.
&&
.MARINE...
TODAY-TONIGHT...SOUTHWEST WIND FLOW REGIME WILL CONTINUE WITH
SPEEDS 10-15 KNOTS OFFSHORE AND 5-10 KNOTS CLOSE TO THE COAST. THE
MAIN MARINER CONCERN WILL BE OFFSHORE MOVING SHOWERS/STORMS WHICH
COULD MOVE OFFSHORE THE TREASURE COAST BY EARLY AFTERNOON.
STEERING FLOW WILL BE WEAK NORTHWARD TO THE VOLUSIA COAST...BUT A
FEW STRONG STORMS COULD AFFECT THE NEARSHORE WATERS LATE IN THE
AFTERNOON.
FRI-FRI NIGHT...SURFACE RIDGE AXIS REMAINS SUPPRESSED TO THE SOUTH.
MAINLY SSW/SW WINDS AROUND 10 KTS. SEAS GENERALLY AOB 3 FT.
WINDS/SEAS LOCALLY HIGHER INVOF OF STRONGER CONVECTION. OFFSHORE
MOVING STORM CELLS REMAIN A THREAT THROUGH THE PERIOD. COVERAGE OF
SHOWERS/STORMS LOOKS RATHER HIGH AND STORMS SHOULD START TO PRODUCE
MORE FREQUENT LIGHTNING STRIKES.
SAT-MON...SURFACE RIDGE AXIS ACROSS THE SOUTHERN PENINSULA INTO
EARLY NEXT WEEK. LITTLE CHANGE IN MOIST SSW/SW WIND FLOW REGIME.
STORM MOTION STILL OFFSHORE BUT WEAKER. BOATERS SHOULD CONTINUE TO
BE VIGILANT FOR MARINE STORMS... ESPECIALLY DURING THE AFTERNOON AND
EVENING. WIND SPEEDS AOB 15 KTS WITH SEAS 2-4 FT GENERALLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 90 74 90 74 / 60 30 50 30
MCO 91 74 90 74 / 60 30 50 30
MLB 91 73 89 74 / 60 30 60 40
VRB 90 73 89 72 / 60 30 70 40
LEE 89 76 91 76 / 60 30 50 30
SFB 92 75 91 74 / 60 30 50 30
ORL 91 76 90 75 / 60 30 50 30
FPR 90 73 89 73 / 60 30 70 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
IMPACT WX...CRISTALDI
FORECASTS...WIMMER
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1031 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA THIS AFTERNOON WITH
SHOWERS AND THUNDERSTORMS EXPECTED. HIGH PRESSURE BUILDS INTO THE
AREA TONIGHT AND PERSISTS INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
14Z OBS AND VIS SAT INDICATING COLD FRONT CURRENTLY BACK OVER
WESTERN PA STRETCHING INTO CENTRAL WV. REFLECTIVITY SHOWING LINE
OF SHOWERS AHEAD OF THE FRONT OVER WESTERN MD WHERE THE INVERSION
HAS WEAKEN ALREADY THIS MORNING...AND SBCAPE VALUES AROUND 1000
J/KG. 14Z HRRR CONTINUES THIS LINE EAST...WITH ANOTHER AREA
FORMING TO THE SOUTH AND WEST...EVENTUALLY CONNECTING THE TWO OVER
NORTHERN VA LATER THIS AFTN.
EXCEPTIONAL SFC MOISTURE OVER THE AREA MAKES THE GREATEST RISK TODAY
FLASH FLOODING FROM EXCESSIVE RAINFALL. ACTIVITY EXPECTED TO BE
PROGRESSIVE...SO THIS THREAT IS ISOLATED AT BEST. THERE IS A
MARGINAL SEVERE RISK EAST OF THE BLUE RIDGE WHERE DIURNAL TIMING OF
ACTIVITY IS BEST (AFTERNOON). HOWEVER...DEEP MOISTURE JUST LIKE
YESTERDAY WILL LIMIT MID LEVEL LAPSE RATES AND THE SEVERE THREAT.
JUST A LOW WET MICROBURST THREAT WITH THE STRONGEST ACTIVITY.
HOT TODAY WITH MAX TEMPS LOW 90S EAST OF THE BLUE RIDGE WHERE
THICK CLOUDS SHOULD HOLD OUT THE LONGEST. DEWPOINTS IN THE LOW TO
MID 70S WILL RESULT IN MAX HEAT INDICES AGAIN AROUND 100F (JUST
LIKE PREVIOUS TWO DAYS). NO HEAT ADVISORY...BUT IT WILL BE
UNCOMFORTABLE UNTIL THE STORMS HIT/FRONT CROSSES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
COLD FRONT CLEARS THE SERN ZONES THURSDAY EVENING WITH DRIER AIR
TRAILING. DEWPOINTS DROP INTO THE UPR 50S/LOW 60S TONIGHT. MIN
TEMPS 60S WEST OF I-95...LOW 70S EAST.
FRIDAY...H85 TEMPS 16-18 WITH MAX TEMPS AROUND 90F. DEWPOINTS WILL
BE DOWN AROUND 60F...SO NO HEAT INDEX IS EXPECTED. DRY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
WEAK HIGH PRESSURE BUILDS FRI NIGHT. A PRESSURE TROUGH
ESTABLISHES SAT WITH SOME MOISTURE RETURN AND A SLIGHT CHANCE OF
SHOWERS AND T-STORMS. SFC RIDGE BUILDS AGAIN SUN GIVING WAY TO A
HOT SUNNY DAY. WINDS TURN SWRLY AGAIN ON MON AS PRESSURE TROUGH
ESTABLISHES WITH SOME MOISTURE RETURN AND A RISK OF T-STORMS. A
CDFNT PUSHES THROUGH THE AREA TUE WITH DRY NWRLY WINDS AND A
COOLING TREND MID TO LATE NEXT WEEK AS HIGH PRES BUILDS OVER THE
REGION. IN SUMMARY...HOT WX DURING THE WEEKEND AND EARLY NEXT WEEK
THEN TURNING COOLER MID WEEK ON. PRECIP LOOKS TO BE BELOW NORMAL
NEXT 7 DAYS.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
MAINLY VFR CONDITIONS FOR THE TAF PERIOD. SCT SHOWERS AND TSTMS
WILL MOVE THRU THE TAF SITES THIS AFTN AHEAD OF AN APPROACHING
COLD FRONT. ANY STORM COULD RESULT IN GUSTY...VRB WINDS AND HEAVY
RAIN WHICH COULD REDUCE VIS TO IFR. ANY CONVECTION WILL EXIT TO
THE EAST BY 02Z THIS EVENING...WITH VFR AND DRY CONDITIONS LASTING
THRU FRIDAY.
A SLIGHT RISK OF T-STORMS SAT AND MON. REST OF THE
TIME LOOKS FINE WITH VFR CONDITIONS.
&&
.MARINE...
SCA FOR ALL WATERS STARTING AT 3PM AND CONTINUING UNTIL LATE
EVENING AS A WEAK COLD FRONT WITH HEAVY AND GUSTY THUNDERSTORMS
CROSS. SCA CONTINUES FOR MAIN BAY WATERS FOR NWLY FLOW 15 TO 20 KT
LATE TONIGHT. FLOW DECREASES TO 10 TO 15 KT FRIDAY.
POSSIBLE SCA SATURDAY AFTERNOON. OTHERWISE...WINDS SHOULD REMAIN
BELOW SCA MOST OF THE 5-DAY FCST PERIOD. A SLIGHT RISK OF T-STORMS
SAT AND MON.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM EDT
FRIDAY FOR ANZ530>533-538>541.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 10 PM EDT
THIS EVENING FOR ANZ535-536-542.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 8 AM EDT
FRIDAY FOR ANZ534-537-543.
&&
$$
SYNOPSIS...BAJ/LFR
NEAR TERM...BAJ/SEARS
SHORT TERM...BAJ
LONG TERM...LFR
AVIATION...BAJ/SEARS/LFR
MARINE...BAJ/LFR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
742 AM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 526 AM EDT THU JUL 30 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS A PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA WHILE A BROAD RIDGE
REMAINS ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE
FEATURES A NW FLOW WILL DOMINATE THE GREAT LAKES REGION ALLOWING A
SERIES OF MAINLY WEAK AND MOISTURE STARVED SHORTWAVES TO PASS THRU
AREA RESULTING IN PERIODIC LIGHT PCPN. TYPICALLY...THESE WEAK
SHORTWAVES ARE POORLY RESOLVED BY MODELS WHICH WILL MAKE FOR A
TRICKY FCST IN THE LONG TERM. IT LOOKS LIKE TEMPERATURES WILL BE
NEAR NORMAL THROUGH THE WEEKEND AND THEN PERHAPS TREND BELOW NORMAL
FOR THE EARLY PART OF NEXT WEEK BEHIND AS A MORE AMPLIFIED SHORTWAVE
AND ASSOC COLD FRONT PASS THROUGH THE UPPER GREAT LAKES REGION.
FRI INTO SAT...MOST OF MODELS HINT AT A FEW WEAK SHORTWAVES MOVING
THROUGH THE AREA...ONE FRI MORNING AND ANOTHER FRI NIGHT. WITH
SEVERAL OF THE MODELS SHOWING 100-300 J/KG OF MLCAPE AHEAD OF THESE
WAVES WILL PROBABLY NEED TO MAINTAIN AT LEAST SLIGHT CHC POPS FOR
ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW EXPECT ANY PCPN
FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
SATURDAY LOOKS TO BE TRENDING DRIER AS MOST OF THE MODELS INDICATE
SHORTWAVE ENERGY PASSING EAST OF THE AREA SAT MORNING...ALTHOUGH A
POCKET OF HIGHER INSTABILITY NOTED ALONG LAKE MI COUNTIES MAY STILL
WARRANT SLIGHT CHC POPS THERE.
TEMPERATURES FRI THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS COMING INTO A LITTLE BETTER AGREEMENT ON TIMING OF STRONGER
SHORTWAVE COMING DOWN FM SCNTRL CANADA AND ASSOC COLD FROPA FOR SUN
NIGHT/MON TIME FRAME. WILL CONTINUE LOW CHC POPS 30-40 PCT AT THIS
TIME...AND GIVEN STRENGTH OF SHORTWAVE THIS MAY BE BEST OPPORTUNITY
TO SEE WIDEPSREAD ALBEIT LIGHT PCPN. MODELS ADVERTISE BELOW NORMAL
TEMPS FOR MON-WED IN THE WAKE OF THE FROPA AS LATEST 00Z ECMWF SHOWS
8H TEMPS DROPPING TO 4-6C BY MON EVENING AND THEN PERSISTING IN THAT
RANGE INTO WED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 742 AM EDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WHILE WINDS SHOULD
REMAIN GUSTY TO 20-25KT AT THE MORE EXPOSED KCMX TERMINAL
OVERNIGHT...NOCTURNAL INVERSION WILL RESULT IN LLWS AT KIWD/KSAW.
AFTER SUNRISE AND ONSET OF DAYTIME HEATING...GUSTY WINDS TO 20-25KT
WILL RETURN TO KIWD/KSAW...AND GUSTS WILL INCREASE TO AROUND 30KT AT
KCMX. THERE MAY BE ISOLD SHRA NEAR KIWD LATE THIS AFTN...BUT
POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE IS TOO LOW TO INCLUDE
ANY MENTION IN FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HUDSON BAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE WEST-
NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND. &&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
714 AM EDT THU JUL 30 2015
LATEST UPDATE...
AVIATION/FIRE WEATHER
.SYNOPSIS...
ISSUED AT 330 AM EDT THU JUL 30 2015
PLEASANT SUMMER WEATHER IS IN STORE OVER THE NEXT FEW DAYS WITH
COMFORTABLE TEMPERATURES AND HUMIDITY LEVELS ALONG WITH PLENTY OF
SUNSHINE AND FRESH WESTERLY BREEZES.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SFC DEW POINTS IN THE 50S HAVE PUSHED INTO SW LWR MI SETTING THE
STAGE FOR SOME STELLAR SUMMER WEATHER THROUGH SATURDAY. HOWEVER
WINDS WILL BE GUSTY IN THE AFTERNOONS WHEN DEEP MIXING AND DRY AIR
MASS/STEEP LAPSE RATES LEADS TO EFFICIENT MOMENTUM TRANSFER OF
STRONGER 25-30 KTS WINDS AT 3000-5000 FT.
OCCASIONAL FAST MOVING SHORTWAVES DIVING SOUTHEAST THROUGH THE
NORTHERN GRTLKS REGION AND ASSOCIATED WEAK SFC TROUGHS MAY SUPPORT A
SLIGHT CHANCE OF A SHOWER OR TSTM BOTH FRIDAY OR SATURDAY. HOWEVER
THE BIG LIMITING FACTOR WILL BE THE MODERATE LOW LEVEL WESTERLY
FLOW OFF LK MI SENDING STABLE AIR WELL INLAND AND PREVENTING ANY
DECENT LOW LEVEL CONVERGENCE. TYPICALLY THIS KEEPS THE BULK OF SW
LWR MI DRY WITH A LOW POTENTIAL USUALLY LIMITED TO JUST THE
NORTHEAST CORNER OF THE CWFA AROUND CLARE.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SEASONABLE TEMPERATURES ARE ANTICIPATED SATURDAY NIGHT THROUGH
SUNDAY. THERE IS A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS LATE
SATURDAY NIGHT AND SUNDAY WITH A POTENTIALLY BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE SUNDAY NIGHT OR MONDAY WITH A
STRONGER COLD FRONT AND AS THE LONGWAVE UPPER LEVEL TROUGH
BECOMES MORE AMPLIFIED OVER THE GREAT LAKES REGION.
THE EVOLUTION OF THE UPPER LEVEL PATTERN FEATURING A RIDGE OUT
WEST AND TROUGH OVER THE EAST SUGGESTS THAT TEMPS FOR THE EARLY
TO MIDDLE PORTION OF NEXT WEEK WILL LIKELY AVERAGE A LITTLE BELOW
NORMAL WITH A CONTINUED CHC FOR A FEW SHOWERS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 713 AM EDT THU JUL 30 2015
THE MAIN ISSUE FOR AVIATION INTERESTS TODAY IS THE WINDS. EXPECT
WESTERLY SFC WINDS TO BE SUSTAINED AROUND 15 KNOTS BY NOON WITH
GUSTS REACHING 25 KNOTS THIS AFTERNOON. SFC WINDS WILL DIMINISH
BELOW 10 KNOTS AFTER SUNSET. CLR/VFR CONDITIONS WILL CONTINUE
TODAY AND TONIGHT AND THIS IS HIGH CONFIDENCE DUE TO THE VERY DRY
AIR MASS IN PLACE.
&&
.MARINE...
ISSUED AT 330 AM EDT THU JUL 30 2015
WE ARE STILL LOOKING AT A BORDERLINE SMALL CRAFT ADVISORY/BEACH
HAZARD STATEMENT TODAY. LACK OF COLD ADVECTION SHOULD KEEP THINGS
FROM GETTING TOO OUT OF HAND. THE LATEST RUC WIND GUIDANCE HAS
THE STRONGEST WINDS OVER LK MI OCCURRING THIS MORNING... OUT OF
THE WEST-NORTHWEST... THEN DECREASING AFTER THAT WHILE ACTUALLY
BACKING TO THE SOUTHWEST.
THE IDEA IS THAT ONCE THE STRONGER HEATING AND DEEPER MIXING
COMMENCES OVER THE LAND AREAS THIS AFTERNOON WE END UP SEEING A
REVERSAL IN THE LAND/LAKE PRESSURE AND WIND REGIME... LEADING TO
A DECREASING TREND OVER THE WATER WHILE INCREASING OVER THE LAND.
LATEST BUOY OBSERVATIONS SHOW SOLID 3 FOOTERS OCCURRING AT 3 AM AND
WAVE MODEL GUIDANCE SUGGESTS A BRIEF SPIKE TO AROUND 4 FEET BETWEEN
ABOUT 6 AM AND NOON. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS AND
POST HEADLINES IF BUOY WAVE HEIGHTS CONTINUE TO TREND UP.
&&
.FIRE WEATHER...
ISSUED AT 713 AM EDT THU JUL 30 2015
THE COMBINATION OF DRY FUELS... WARM TEMPERATURES IN THE LOWER TO
MID 80S... A DRY AIR MASS... AND GUSTY WEST WINDS WILL RESULT IN
AN ELEVATED FIRE DANGER OVER THE NEXT FEW DAYS. RAIN CHANCES ARE
EXTREMELY LOW THROUGH SATURDAY AND IT HAS BEEN PREDOMINATELY DRY
FOR THE PAST 10 DAYS.
&&
.HYDROLOGY...
ISSUED AT 1151 AM EDT WED JUL 29 2015
RIVER LEVELS ARE FALLING AND WELL BELOW BANKFULL. THE MAIN CHANCE OF
RAIN IN THE NEXT 7 DAYS WOULD BE SUNDAY INTO MONDAY NIGHT. LOCALLY
HEAVY RAIN IS POSSIBLE... BUT ONLY PONDING OF WATER IS EXPECTED AWAY
FROM THE RIVERS. RIVERS MAY SHOW RISES... BUT SHOULD NOT REACH BANK
FULL LEVELS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...LAURENS
AVIATION...MEADE
FIRE WEATHER...MEADE
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1136 AM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 1200 PM THURSDAY...
AN UPPER LEVEL RIDGE IS EXPECTED TO PERSIST OVER THE WESTERN CONUS
THROUGH THE EXTENDED PERIOD...WITH THE RIDGE UNDERGOING FURTHER
AMPLIFYING OVER THE ROCKIES BY EARLY NEXT WEEK. DOWNSTREAM IN THE
CAROLINAS AND MID-ATLANTIC...PERSISTING TROUGHING /CYCLONIC FLOW/
ALOFT WILL PREVAIL. THOUGH NUMEROUS SMALL AMPLITUDE DISTURBANCES
/SHORTWAVES/ WILL NO DOUBT BE PRESENT IN THIS AMPLIFIED PATTERN...
THE BULK OF NORTH CAROLINA IS EXPECTED TO REMAIN ALONG/WEST THE BASE
OF THE UPPER LEVEL TROUGH AXIS...WHERE MOISTURE WILL BE LESS
FAVORABLE FOR (OR PERHAPS INSUFFICIENT TO SUPPORT) DIURNAL
CONVECTION...EXCEPT IN EASTERN/COASTAL PORTIONS OF THE CAROLINAS.
WILL MAKE LITTLE CHANGE TO THE PREVIOUS FORECAST INDICATING HIGHS IN
THE LOWER TO MID 90S...LOWS IN THE LOWER 70S...AND DIURNAL PRECIP
CHANCES CONFINED PRIMARILY TO THE SE COASTAL PLAIN. IT SHOULD BE
NOTED THAT A WESTWARD SHIFT IN THE UPPER LEVEL PATTERN (RIDGE/TROUGH
AXES) OVER THE LOWER 48 WOULD RESULT IN INCREASED PRECIP CHANCES
ACROSS PORTIONS OF CENTRAL NC...PARTICULARLY ALONG/EAST OF HWY 1...
THOUGH NO SIGNIFICANT CHANGE IS APPARENT AT THIS TIME. -VINCENT
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM THURSDAY...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND CROSS THE
AREA LATE THIS EVENING AND TONIGHT. INSTABILITY IS EXPECTED TO BE
LIMITED WHEN THE FRONT ARRIVES...ESPECIALLY TONIGHT AS THE FRONT
MOVES EAST ACROSS CENTRAL NC. SCATTERED SHOWERS AND A FEW ISOLATED
STORMS WILL BE POSSIBLE ALONG THE FRONT...FIRST AROUND KINT/KGSO
AFTER 21Z AND THEN KRDU/KRWI/KFAY IN THE 00Z TO 06Z TIME FRAME.
WHILE WIDESPREAD ADVERSE AVIATION CONDITIONS ARE NOT EXPECTED...A
HEAVY DOWNPOUR AND BRIEF PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE AT
AT TAF SITE. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND THE
FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST ON
FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...VINCENT
AVIATION...22
AREA FORECAST DISCUSSION...CORRECTED
NWS RALEIGH NC
1100 AM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 405 AM THURSDAY...
THE MODELS GENERALLY AGREE THAT A RELATIVELY AMPLIFIED FLOW
PATTERN...ONE CHARACTERIZED BY A STRONG RIDGE CENTERED OVER THE
SOUTHWESTERN US AND DOWNSTREAM A BROAD TROUGH EAST OF THE
ROCKIES...WILL PERSIST THROUGH THE MEDIUM RANGE...THOUGH WITH
INDICATION FROM THE ENSEMBLE MEANS OF SOME RELAXATION OF THE
FLOW/TOWARD LESS AMPLIFIED-MORE ZONAL LATE NEXT WEEK.
DESPITE THE PRESENCE OF A TROUGH AND CYCLONIC FLOW ALOFT OVER THE
EASTERN US...UNSEASONABLY DRY AIR WILL HAVE SPREAD IN THE LEE OF THE
APPALACHIANS...BEHIND A LEAD FRONTAL ZONE FORECAST TO CROSS THE RAH
FORECAST AREA LATER TONIGHT. THIS BOUNDARY WILL EFFECTIVELY PIN RICH
MOISTURE ALONG COASTAL AREAS...WITH MUCH DRIER AIR...PARTICULARLY
WITH DIURNAL HEATING/BL MIXING WESTWARD ACROSS CENTRAL NC. THIS
DRIER AIR WILL SIGNIFICANTLY HINDER THE DEVELOPMENT OF ANY
APPRECIABLE CAPE AND PRECIPITATION CHANCES THROUGHOUT THE FORECAST
PERIOD...WITH THE RELATIVELY HIGHER CHANCES/~25 PERCENT ALONG AND
EAST OF A PIEDMONT TROUGH EACH LATE AFTERNOON-EARLY EVENING.
ANY EVEN WEAK STORM WRT REFLECTIVITY...HOWEVER...WOULD POSE A RISK OF
STRONG...EVAPORATIVELY-COOLED DOWNBURST WINDS IN AN ENVIRONMENT
CHARACTERIZED BY STEEP/NEAR DRY ADIABATIC LOW LEVEL LAPSE RATES AND
LARGE/~30-35 DEGREE SURFACE DEWPOINT DEPRESSIONS...DRIVEN BY A
COMBINATION OF THE AFOREMENTIONED MIXING OUT OF AN ALREADY
CONTINENTAL AIR MASS...AND HOT SURFACE TEMPERATURES IN THE LOWER TO
MIDDLE 90S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM THURSDAY...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND CROSS THE
AREA LATE THIS EVENING AND TONIGHT. INSTABILITY IS EXPECTED TO BE
LIMITED WHEN THE FRONT ARRIVES...ESPECIALLY TONIGHT AS THE FRONT
MOVES EAST ACROSS CENTRAL NC. SCATTERED SHOWERS AND A FEW ISOLATED
STORMS WILL BE POSSIBLE ALONG THE FRONT...FIRST AROUND KINT/KGSO
AFTER 21Z AND THEN KRDU/KRWI/KFAY IN THE 00Z TO 06Z TIME FRAME.
WHILE WIDESPREAD ADVERSE AVIATION CONDITIONS ARE NOT EXPECTED...A
HEAVY DOWNPOUR AND BRIEF PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE AT
AT TAF SITE. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND THE
FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST ON
FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
CORRECTED ISSUE TIME
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...26
AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1000 AM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 405 AM THURSDAY...
THE MODELS GENERALLY AGREE THAT A RELATIVELY AMPLIFIED FLOW
PATTERN...ONE CHARACTERIZED BY A STRONG RIDGE CENTERED OVER THE
SOUTHWESTERN US AND DOWNSTREAM A BROAD TROUGH EAST OF THE
ROCKIES...WILL PERSIST THROUGH THE MEDIUM RANGE...THOUGH WITH
INDICATION FROM THE ENSEMBLE MEANS OF SOME RELAXATION OF THE
FLOW/TOWARD LESS AMPLIFIED-MORE ZONAL LATE NEXT WEEK.
DESPITE THE PRESENCE OF A TROUGH AND CYCLONIC FLOW ALOFT OVER THE
EASTERN US...UNSEASONABLY DRY AIR WILL HAVE SPREAD IN THE LEE OF THE
APPALACHIANS...BEHIND A LEAD FRONTAL ZONE FORECAST TO CROSS THE RAH
FORECAST AREA LATER TONIGHT. THIS BOUNDARY WILL EFFECTIVELY PIN RICH
MOISTURE ALONG COASTAL AREAS...WITH MUCH DRIER AIR...PARTICULARLY
WITH DIURNAL HEATING/BL MIXING WESTWARD ACROSS CENTRAL NC. THIS
DRIER AIR WILL SIGNIFICANTLY HINDER THE DEVELOPMENT OF ANY
APPRECIABLE CAPE AND PRECIPITATION CHANCES THROUGHOUT THE FORECAST
PERIOD...WITH THE RELATIVELY HIGHER CHANCES/~25 PERCENT ALONG AND
EAST OF A PIEDMONT TROUGH EACH LATE AFTERNOON-EARLY EVENING.
ANY EVEN WEAK STORM WRT REFLECTIVITY...HOWEVER...WOULD POSE A RISK OF
STRONG...EVAPORATIVELY-COOLED DOWNBURST WINDS IN AN ENVIRONMENT
CHARACTERIZED BY STEEP/NEAR DRY ADIABATIC LOW LEVEL LAPSE RATES AND
LARGE/~30-35 DEGREE SURFACE DEWPOINT DEPRESSIONS...DRIVEN BY A
COMBINATION OF THE AFOREMENTIONED MIXING OUT OF AN ALREADY
CONTINENTAL AIR MASS...AND HOT SURFACE TEMPERATURES IN THE LOWER TO
MIDDLE 90S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM THURSDAY...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND CROSS THE
AREA LATE THIS EVENING AND TONIGHT. INSTABILITY IS EXPECTED TO BE
LIMITED WHEN THE FRONT ARRIVES...ESPECIALLY TONIGHT AS THE FRONT
MOVES EAST ACROSS CENTRAL NC. SCATTERED SHOWERS AND A FEW ISOLATED
STORMS WILL BE POSSIBLE ALONG THE FRONT...FIRST AROUND KINT/KGSO
AFTER 21Z AND THEN KRDU/KRWI/KFAY IN THE 00Z TO 06Z TIME FRAME.
WHILE WIDESPREAD ADVERSE AVIATION CONDITIONS ARE NOT EXPECTED...A
HEAVY DOWNPOUR AND BRIEF PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE AT
AT TAF SITE. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND THE
FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST ON
FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...26
AVIATION...22
AREA FORECAST DISCUSSION
NWS TULSA OK
1051 AM CDT THU JUL 30 2015
...UPDATE...
.DISCUSSION...
THUNDERSTORMS MADE A RUN AT THE NORTHWESTERN PORTION OF THE
FORECAST AREA THIS MORNING. WE RAISED POPS IN REACTION TO THIS
FROM ABOUT TULSA NORTHWESTWARD. CURRENTLY... EASTWARD PROGRESSION
OF PRECIP SEEMS TO BE COMING TO A HALT... IN AGREEMENT WITH THE
HRRR AND RUC MODELS. CLOUD TOPS ARE WARMING RAPIDLY ON THE
EASTERN SIDE OF THE PRECIP SHIELD AS WELL... CONFIRMING THAT THE
THUNDERSTORM ACTIVITY HAS JUST ABOUT REACHED ITS EASTWARD LIMIT.
THAT SAID... AN OUTFLOW BOUNDARY IS RACING EASTWARD ACROSS OSAGE
AND PAWNEE COUNTIES... WHICH MAY BE ENOUGH TO INIATE ISOLATED
CONVECTIVE ACTIVITY. THIS WILL JUSTIFY LEAVING THE HIGHER POPS IN
FOR THE NEXT FEW HOURS. UPDATED PRODUCTS HAVE BEEN SENT.
&&
.PREV DISCUSSION... /ISSUED 634 AM CDT THU JUL 30 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
MOIST AND UNSTABLE AIR MASS ACROSS THE REGION ALONG WITH A WEAK COLD
FRONT IN THE PROXIMITY WILL SUPPORT SCATTERED TSRA THROUGH TONIGHT.
ACTIVITY IN SOUTH CENTRAL KS MAY IMPACT BVO/TUL/RVS LATER THIS
MORNING. BEST CHANCES SHOULD BE AT NERN OK SITES THIS AFTERNOON AND
MLC/FSM AFTER 00Z. ALTHOUGH LAYERED CLOUDS WILL BE THE RULE FOR MUCH
OF THIS FORECAST PERIOD...VFR CONDITIONS SHOULD PREVAIL OUTSIDE OF
TSRA...WHICH WILL REDUCE VSBY TO MVFR.
PREV DISCUSSION... /ISSUED 259 AM CDT THU JUL 30 2015/
DISCUSSION...
WEAK SFC BOUNDARY HAS PUSHED WELL INTO ERN OK THIS MORNING. THIS
FEATURE WILL SERVE AS FOCUS FOR WIDELY SCATTERED TO SCATTERED
CONVECTION TOMORROW AND INTO FRIDAY...ESPECIALLY OVER ERN OK. HEAT
ADVISORY CRITERIA WILL BE FLIRTED WITH ACROSS PARTS OF EAST
CENTRAL AND SOUTHEAST OKLAHOMA. WILL FOREGO AN ADVISORY AT THIS
TIME GIVEN MARGINAL VALUES EXPECTED ALONG WITH THE SHORT DURATION.
MODELS HAVE REMAINED FAIRLY CONSISTENT IN PUSHING THE BOUNDARY
FURTHER WEST BY LATER IN THE DAY FRIDAY...WITH MOST CONVECTION
ACROSS CENTRAL AN WESTERN SECTIONS OF OKLAHOMA. UPPER HIGH TO
REMAINED POSITIONED TO THE WEST OF THE FA THROUGH THE FORECAST
PERIOD...WITH SOME HEIGHT RISES NOTED THROUGH THE WEEKEND PER THE
GFS. LATER IN THE FORECAST CYCLE...ECMWF FLATTENS THE RIDGE AS AS
WAVE TRAVERSES THE CENTRAL PLAINS...WHILE THE GFS MAINTAINS
HIGHER HEIGHTS/WEAK NW FLOW. WILL KEEP FORECAST DRY FOR NOW BEYOND
FRIDAY. TEMPERATURES WILL INCREASE SOME OVER THE WEEKEND...BUT
WILL LIKELY NOT BE AS HOT AS OBSERVED THE LAST WEEK GIVEN THE
POSITIONING OF THE UPPER RIDGE TO THE WEST.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...06
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1027 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM...THE 12Z SFC ANALYSIS SHOWED THE COLD FRONT PUSHING
INTO THE SMOKIES AND GREAT TENN VALLEY. THE FRONT WILL CONTINUE TO
PUSH ACRS THE MTNS THRU MIDDAY...THEN ACRS THE PIEDMONT THIS AFTN.
THERE IS LESS CLOUD COVER AT THIS TIME OF DAY THAN THE LAST FEW
DAYS. SO TEMPS ARE WARMING QUICKLY...DESPITE HUMID BL...WITH DEWPTS
STILL IN THE LWR-MID 70S. THIS IS RESULTING IN SBCAPE ALREADY IN THE
1500-2500 J/KG RANGE ON THE SPC MESOANALYSIS PAGE ACRS THE PIEDMONT.
I HAVE BUMPED MAX TEMPS UP A DEG OR TWO GIVEN THE TRENDS. AS FOR
POPS...ONE WOULD EXPECT DECENT COVERAGE OF SHWRS AND TSTMS...GIVEN
DECENT INSTBY AND A BOUNDARY WORKING THRU THE AREA. HOWEVER...THE
LATEST CAMS ARE A BIT MUTED. I TRIED BLENDING IN CAM POP...BUT THAT
DROPPED POP DOWN ACRS MUCH OF THE AREA. SO I PRETTY MUCH KEPT POPS
AS IS...WHICH IS IN THE 30-40 PCT RANGE. SEVERE THREAT IS STILL
MARGINAL...WITH WIND BEING THE MAIN THREAT.
AS OF 650 AM...THE FORECAST APPEARS IN GOOD SHAPE. I WILL TAYLOR
POPS TO REFLECT LIGHT RETURNS OVER THE WESTERN NC MTNS. IN
ADDITION...I WILL REDUCE FOG MENTION.
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AT KCLT...THE PRIMARY FORECAST CHALLENGE WILL BE THE TIMING OF A
SWEEPING COLD FRONT AND ASSOCIATED WIND SHIFT. AT 10Z...THE COLD
FRONT WAS ANALYZED OVER MIDDLE KY/TN. THE COLD FRONT IS FORECAST TO
SWEEP EAST TODAY...REACHING THE NC PIEDMONT LATE THIS AFTERNOON. I
WILL FORECAST LIGHT SW WINDS ACROSS THE CLT TERMINAL THROUGH THE
MORNING HOURS...VEERING WNW BY 17Z. A BROKEN BAND OF SHRA/TSRA WILL
LIKELY FORM AHEAD OF THE FRONT...TRACKING SE. BASED ON THE 6Z
NAM...THE MOST LIKELY TIME WINDOW FOR CONVECTION SHOULD OCCUR
BETWEEN 19Z TO 22Z...HIGHLIGHTED WITH A TEMPO. IN THE WAKE OF THE
FRONT...NNW WINDS SHOULD STRENGTHEN TO 5 TO 10KTS WITH VFR
OVERNIGHT CONDITIONS.
ELSEWHERE...SUNRISE TEMPERATURES HAVE CLOSED IN ON CROSSOVER VALUES
YIELDING LIGHT FOG AT KGSP AND KGMU. KAVL HAS SEEN SOME VLIFR CLOUDS
THIS MORNING...BUT LATEST OBS INDICATE THAT THESE CEILINGS HAVE
DISSIPATED. I WILL LIMIT SKY TO SCT003 IN THE INITIAL LINE OF THE
KAVL TAF...WILL MONITOR CLOSELY THIS MORNING. PRE FRONTAL CONVECTION
SHOULD FORM AHEAD OF THE COLD FRONT...WITH COVERAGE INCREASING AS IT
MOVES EAST. I WILL USE A TEMPO FOR EACH SITE EAST OF THE MTNS
INDICATING A EARLY TO MID AFTERNOON BAND OF TSRA. AFTER THE
CONVECTION...WINDS SHOULD VEER NNW AND REMAIN THROUGH THE REST OF
THE TAF PERIOD.
OUTLOOK...HIGH PRESSURE WITH BUILD IN BEHIND A PASSING COLD FRONT
LATE ON THURSDAY ALLOWING FOR GENERALLY DRY AND QUIET WEATHER
THROUGH THE WEEKEND. CHANCES FOR SHOWERS/THUNDERSTORMS AND THUS
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 98% HIGH 88% MED 67% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 88% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
655 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM...THE FORECAST APPEARS IN GOOD SHAPE. I WILL TAYLOR
POPS TO REFLECT LIGHT RETURNS OVER THE WESTERN NC MTNS. IN
ADDITION...I WILL REDUCE FOG MENTION.
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AT KCLT...THE PRIMARY FORECAST CHALLENGE WILL BE THE TIMING OF A
SWEEPING COLD FRONT AND ASSOCIATED WIND SHIFT. AT 10Z...THE COLD
FRONT WAS ANALYZED OVER MIDDLE KY/TN. THE COLD FRONT IS FORECAST TO
SWEEP EAST TODAY...REACHING THE NC PIEDMONT LATE THIS AFTERNOON. I
WILL FORECAST LIGHT SW WINDS ACROSS THE CLT TERMINAL THROUGH THE
MORNING HOURS...VEERING WNW BY 17Z. A BROKEN BAND OF SHRA/TSRA WILL
LIKELY FORM AHEAD OF THE FRONT...TRACKING SE. BASED ON THE 6Z
NAM...THE MOST LIKELY TIME WINDOW FOR CONVECTION SHOULD OCCUR
BETWEEN 19Z TO 22Z...HIGHLIGHTED WITH A TEMPO. IN THE WAKE OF THE
FRONT...NNW WINDS SHOULD STRENGTHEN TO 5 TO 10KTS WITH VFR
OVERNIGHT CONDITIONS.
ELSEWHERE...SUNRISE TEMPERATURES HAVE CLOSED IN ON CROSSOVER VALUES
YIELDING LIGHT FOG AT KGSP AND KGMU. KAVL HAS SEEN SOME VLIFR CLOUDS
THIS MORNING...BUT LATEST OBS INDICATE THAT THESE CEILINGS HAVE
DISSIPATED. I WILL LIMIT SKY TO SCT003 IN THE INITIAL LINE OF THE
KAVL TAF...WILL MONITOR CLOSELY THIS MORNING. PRE FRONTAL CONVECTION
SHOULD FORM AHEAD OF THE COLD FRONT...WITH COVERAGE INCREASING AS IT
MOVES EAST. I WILL USE A TEMPO FOR EACH SITE EAST OF THE MTNS
INDICATING A EARLY TO MID AFTERNOON BAND OF TSRA. AFTER THE
CONVECTION...WINDS SHOULD VEER NNW AND REMAIN THROUGH THE REST OF
THE TAF PERIOD.
OUTLOOK...HIGH PRESSURE WITH BUILD IN BEHIND A PASSING COLD FRONT
LATE ON THURSDAY ALLOWING FOR GENERALLY DRY AND QUIET WEATHER
THROUGH THE WEEKEND. CHANCES FOR SHOWERS/THUNDERSTORMS AND THUS
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL LOW 31% HIGH 100% HIGH 100% LOW 58%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1023 AM CDT THU JUL 30 2015
.UPDATE...
HAVE MADE UPDATES THIS MORNING TO INCREASE TEMPORAL RESOLUTION AND
ADD SPATIAL DETAIL TO POP AND WEATHER GRIDS. ALSO ADJUSTED WINDS
BASED ON CURRENT TRENDS. LATEST RADAR TRENDS SHOW AN INCREASING
CONVECTION IN THE NORTHEAST. THIS SEEMS TO BE OCCURRING DUE TO WEAK
BROAD ISENTROPIC ASCENT ATOP SHALLOW OUTFLOW FROM EARLIER CONVECTION
THAT OCCURRED IN THE NORTHWEST. SATELLITE DERIVED PWAT INDICATE
VALUES RANGING FROM AROUND 1.5 INCHES ACROSS THE NORTHERN AND CENTRAL
PORTIONS OF THE FORECAST AREA (AND THIS MATCHES UP WELL WITH 12Z KAMA
SOUNDING) TO NEARLY 2 INCHES IN THE NORTHEAST. GIVEN MOIST LOW LEVELS
AM CONCERNED ABOUT LOCALIZED AREAL FLOODING MAINLY IN THE NORTHEAST
IF MORE WIDESPREAD CONVECTION CAN PERSIST INTO THE AFTERNOON. WILL
CONTINUE TO MONITOR TRENDS.
BRB
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT THU JUL 30 2015/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
17/15
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
904 AM CDT THU JUL 30 2015
.DISCUSSION...
SEEING MORE CLOUD COVER ACROSS EASTERN AREAS THIS AM AS DEEPER
MOISTURE ADVECTS IN FROM THE EAST. QUITE A DIFFERENCE
BETWEEN THE 12Z LCH AND CRP SOUNDINGS (2.2 VS. 1.5 INCH
PRECIPITABLE WATER). GIVEN THIS DEEPER MOISTURE ACROSS EASTERN
AREAS...AND THE LATEST HRRR REFLECTIVITY FORECAST...BELIEVE THAT
THE CHC POP ACROSS THE EAST AND SLIGHT CHC POP ACROSS THE WEST IS
ON TRACK FOR THIS AFT/EVE. MAX TEMPS NEAR 100 INLAND AND LOWER TO
MID 90S COAST APPEARS ON TRACK AS WELL. NO SIGNIFICANT CHGS TO
THE ONGOING FCST. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 99 78 99 76 101 / 10 20 30 10 10
HOUSTON (IAH) 99 78 98 76 100 / 30 30 30 20 20
GALVESTON (GLS) 92 82 92 81 92 / 30 30 30 20 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...33
AREA FORECAST DISCUSSION
NWS AMARILLO TX
635 AM CDT THU JUL 30 2015
.AVIATION...
12Z TAFS... WIDESPREAD MVFR/IFR CONDITIONS THIS MORNING ACROSS THE
PANHANDLES. MEDIUM CONFIDENCE IN CIGS SLOWLY IMPROVING TO MVFR/LOW END
VFR MID TO LATE MORNING. SCATTERED CONVECTION IS POSSIBLE ACROSS THE
OKLAHOMA AND WESTERN TEXAS PANHANDLES THIS MORNING...AND DEVELOPING
AGAIN LATER THIS AFTERNOON AND EVENING ACROSS MUCH OF THE AREA. WINDS
WILL BE MOSTLY FROM THE NORTHEAST TO EAST AND BECOMING SOUTHEASTERLY
THIS AFTERNOON AT 5 TO 12KTS.
ELSENHEIMER
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT THU JUL 30 2015/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
18/14
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
919 AM EDT THU JUL 30 2015
.SYNOPSIS...
A FRONT WILL SLIDE ACROSS OUR REGION TODAY...STALLING ALONG THE
SOUTHEAST COAST FRIDAY INTO SATURDAY. THIS WILL ALLOW FOR HIGH
PRESSURE TO KEEP MOST OF THE AREA DRY THROUGH THE WEEKEND...AS IT
MOVES IN FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 919 AM EDT THURSDAY...
ADJUSTED TEMPERATURES WITH LATEST SFC OBS AND GUIDANCE THIS
MORNING INTO THIS AFTERNOON. KFCX WSR-88D SHOWED SCATTERED
CONVECTION MOVING EASTWARD ACROSS SOUTHEAST WEST VIRGINIA
SOUTHWARD INTO THE WESTERN MOUNTAINS. THIS MORNING 12Z/8AM RNK
SOUNDING INDICATED A NORTHWEST FLOW AND PWATS AROUND 1.5 INCHES.
STILL CAN NOT COMPLETELY RULE OUT LOCALLY HEAVY RAINS AND
ISOLATED THREAT FOR WIND GUSTS WITH STRONGER STORMS GIVEN HIGHER
LOW LEVEL LAPSE RATES COMBINED WITH HIGH MOISTURE CONTENT.
LEANED POPS THIS MORNING INTO THIS AFTERNOON TOWARDS HRRR WHICH
CAPTURED CURRENT RADAR IMAGES THE BEST. MORE CHANGES LATER THIS
MORNING.
AS OF 715 AM EDT THURSDAY...
AREA OF SHOWERS/EMBEDDED THUNDERSTORMS MOVING ACROSS SE WV THIS
MORNING INVOF FRONTAL BOUNDARY. THIS FRONT IS GOING TO SLIDE
SOUTHEAST THROUGH THE DAY...WITH MAIN FOCUS WORKING EAST TOWARD
THE PIEDMONT BY EARLY AFTERNOON. NO MAJOR CHANGES TO THE FORECAST
BEYOND UPDATING CHANCES THROUGH 9 AM INTO THE ALLEGHANYS.
PREVIOUS VALID DISCUSSION...
EXPECT FOG TO BE ERODE OR DISSIPATE BY 13Z.
MODELS ARE SIMILAR IN TIMING OF THE FRONT BUT EXPECT TYPICAL
DIFFERENCES ON WHERE BEST THREAT OF SHOWERS/STORMS WILL BE. GIVEN
THERE WILL BE MORE CLOUDS AROUND IN THE WEST THIS MORNING ALONG WITH
FRONT MOVING IN BY LATE MORNING...THINK THE STORM THREAT IS LOWER
OVER THE MTNS. AS WE HEAD INTO THE AFTERNOON...THE EASTERN CWA
SHOULD HAVE ENOUGH SUN TO STEEPEN THE LOW LVL LAPSE RATES. THOUGH
THE DYNAMICS ARE NOT THAT GREAT WITH THE FRONT...CANNOT RULE OUT THE
ISOLATED THREAT FOR A MICROBURST GIVEN HIGHER LOW LVL LAPSE RATES
COMBINED WITH HIGH MOISTURE CONTENT. THE STORM PREDICTION CENTER HAS
THE MARGINAL RISK OVER THE NE PIEDMONT NE OF LYH...AND TO THE SOUTH
OF YADKINVILLE NC. HOWEVER...THINK THE EASTERN CWA WILL HAVE JUST
ENOUGH OF A THREAT TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK.
HIGHS TODAY WILL DEPEND ON CLOUD COVER...THINKING THE WEST WILL ONLY
GET INTO THE UPPER 70S TO MID 80S...WHILE THE ROANOKE VALLEY EAST TO
THE PIEDMONT HIT UPPER 80S...LOWER 90S. SOME HEAT INDICES COULD
REACH 100 FROM FARMVILLE TO DANVILLE IF MORE SUNSHINE OCCURS GIVEN
DEWPOINTS IN THE LOWER 70S.
TONIGHT...THE MODELS SHOW DRIER AIR OVERSPREADING OUR WESTERN CWA
WHILE THE FRONT EAST SLOWS DOWN AND KEEPS THE HIGHER DEWPOINTS
LINGERING LONGER. THE SHOWER/STORM THREAT WILL BE MOVING OUT OF THE
PIEDMONT BY MIDNIGHT...WITH SKIES CLEARING.
THE DEWPOINTS OVER THE MTNS WILL BE DROPPING INTO THE 50S BY DAWN
FRIDAY...AND YOU WILL BE ABLE TO TELL FRIDAY MORNING THAT THE
HUMIDITY IS LOWER. LOWS WILL RANGE FROM THE MID 50S DEEPER VALLEYS
OVER SE WV/FAR SW VA...TO AROUND 60 ELSEWHERE WEST OF THE BLUE
RIDGE...TO MID 60S FROM ROANOKE EAST TO THE PIEDMONT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
FORECAST MODELS AREA IN VERY GOOD AGREEMENT THAT THE WEATHER PATTERN
FOR THIS WEEKEND WILL BE DOMINATED BY A BROAD UPPER LEVEL TROUGH
EXTENDING SOUTHWARD FROM EASTERN CANADA...WHILE HIGH PRESSURE BUILDS
EASTWARD FROM THE CENTRAL PLAINS IN THE LOW LEVELS. THE HIGH WILL
BRING WITH IT DRIER AIR...PUSHING DEWPOINTS INTO THE 50S AND LOW
60S...WHICH WILL CUT DOWN ON THE HUMIDITY FOR THE WEEKEND.
EXPECT ABUNDANT SUNSHINE FOR FRIDAY WITH VERY LOW RAIN CHANCES IN A
LIGHT NORTH NORTHWESTERLY WINDFLOW.
A REINFORCING COLD FRONT WILL APPROACH FROM THE NORTH ON SATURDAY...
POSSIBLY BRINGING A FEW SHOWERS TO THE WESTERN RIDGES. CONSIDERING
LIMITED MOISTURE IN PLACE AHEAD OF THE APPROACHING FRONT...WILL
MAINTAIN LOW RAIN CHANCES FOR NOW.
WEAK HIGH PRESSURE WILL RETURN FOR SUNDAY...MAKING FOR MOSTLY CLEAR
SKIES...ALTHOUGH CANNOT RULE OUT A FEW POP UP SHOWERS DURING
AFTERNOON/EVENING.
AFTERNOON TEMPERATURES WILL RANGE FROM THE LOW 80S/A FEW UPPER 70S
ACROSS THE MOUNTAINS...TO THE UPPER 80S/LOW 90S ACROSS THE PIEDMONT
EACH DAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 50S/LOW 60S
WEST...TO THE LOW/MID 60S EAST. WITH COOL AIR DRAINAGE...MAY SEE A
FEW OF THE DEEPER MOUNTAIN VALLEYS FALL TO NEAR 50 DEGREES IN SPOTS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 1230 PM EDT WEDNESDAY...
PREDOMINATE UPPER TROFFINESS ACROSS THE MID ATLANTIC WILL KEEP NW FLOW
ALOFT IN PLACE FROM THE WEEKEND THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. THIS SHOULD INITIALLY KEEP OVERALL DRY WEATHER IN PLACE WITH
SURFACE HIGH PRESSURE BUILDING ACROSS THE REGION FROM THE NW SUNDAY-
MONDAY...AND TO THE SOUTH AHEAD OF A REINFORCING COLD FRONT BY
WEDNESDAY. ONLY EXCEPTION TO THIS COULD BE WITH MOISTURE BEING LIFTED
BACK INTO THE SE EARLY NEXT WEEK WITH LOW PRESSURE DEVELOPING ALONG THE
RESIDUAL FRONT NEAR THE COAST. HOWEVER THE EARLIER ECMWF AND CMC ABOUT
THE ONLY SOLUTIONS THAT STILL HINT AT THIS SO BASICALLY LEAVING OUT
MOST POPS OUTSIDE OF SOMETHING ISOLATED SE SECTIONS ON MONDAY.
COLUMN WILL GRADUALLY MOISTEN ENOUGH BY MIDWEEK TO POSSIBLY SUPPORT A
BIT MORE CONVECTION AS WEAK SHORTWAVES ALOFT TRAVERSE THE NW FLOW ON
TUESDAY AHEAD OF A STRONGER UPPER LOW AND COLD FRONT TO THE NORTH
WEDNESDAY. GUIDANCE REMAINS A BIT HESITANT TO PRODUCE MUCH IN THE WAY
OF PRECIP GIVEN MAIN LIFT TO THE NORTH BUT APPEARS ENOUGH FOCUS WITH
HEATING TO SUPPORT SOME LOW POPS TUESDAY AFTERNOON. BETTER CHANCES MAY
COME WEDNESDAY AS THE FRONT SAGS TOWARD THE AREA FROM THE NORTH AND
DEWPOINTS RISE BUT EVEN THEN SUPPORT THIS FAR SOUTH LACKING SO CHANCE
POPS IN ORDER. OTRW MAINLY A PERSISTENCE FORECAST WITH HIGHS 80S TO
AROUND 90 SE AND 60S OVERNIGHT EXCEPT SOME COOLER 50S VALLEYS EARLY IN
THE WEEK AS DEWPOINTS/HUMIDITY REMAIN LOW.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
AS OF 720 AM EDT THURSDAY...
AMD NOT SKED ADDED TO LYH AS NO COMMS INTO OUR COMPUTER SYSTEM.
FAA NOTIFIED.
AS WE HEAD THROUGH THE MORNING GOING TO SEE VFR CONDITIONS FORM AS
FOG/LOW CLOUDS ERODE. SHOWERS WILL IMPACT THE LWB TERMINAL FOR
ANOTHER 1-2 HRS TIL 13-14Z...THEN SHOULD SEE SCATTERED SHOWERS
AND STORMS FURTHER EAST TODAY. KEPT VCTS AT DAN/LYH AND THINK THIS
WILL BE WHERE BETTER COVERAGE...ALBEIT SCATTERED WILL BE GIVEN
MORE SUNSHINE TO AID IN INSTABILITY AHEAD OF THE FRONT.
ONCE THIS FRONT WORKS EAST THE WINDS WILL COME AROUND TO THE
WEST-NORTHWEST AT 5 TO 12 KTS...THEN WEAKEN THIS EVENING.
WITH DRIER AIR WORKING IN THE FOG THREAT SHOULD BE
MINIMIZED...THOUGH THERE IS A SMALL CHANCE THAT LWB/BCB COULD FOG
IN GIVEN SOME SLIGHTLY COOLER AIR OVER MOIST GROUND.
EXTENDED AVIATION FORECAST...
BEHIND THE FRONT THE WEATHER WILL BE DRY AND VFR FRIDAY THROUGH
SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.EQUIPMENT...
OBSERVATIONS ARE NOT AVAILABLE FROM LYNCHBURG...AND THE FAA HAS
BEEN NOTIFIED OF THIS OUTAGE. NO ESTIMATED TIME OF RESTORATION WAS
GIVEN.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...KK/WP
SHORT TERM...NF
LONG TERM...JH
AVIATION...AMS/KK/WP
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
945 AM MST THU JUL 30 2015
.SYNOPSIS...
HIGH PRESSURE BUILDING OVER THE REGION WILL GRADUALLY REDUCE RAIN
CHANCES TODAY ONWARD INTO THE UPCOMING WEEKEND...AND INTO EARLY NEXT
WEEK WITH AT LEAST SLIGHT CHANCES TO REMAIN OVER SOUTH-CENTRAL
ARIZONA. TEMPERATURES WILL TAKE A SLIGHT DIP BELOW NORMAL TODAY DUE
TO WIDESPREAD CLOUD COVERAGE...BEFORE A SLOW WARMING TREND FRIDAY
INTO EARLY NEXT WEEK AS THE ATMOSPHERE SLOWLY DRIES OUT.
&&
.DISCUSSION...
MORE SUNSHINE TODAY THAN YESTERDAY BUT MOST OF THE 12Z SOUNDINGS
OVER ARIZONA SHOW LESS MOISTURE COMBINED WITH SOMEWHAT WARMER
TEMPERATURES ALOFT. THIS RESULTS IN EVEN LESS CAPE THAN YESTERDAY.
LATEST MODELS REFLECT THIS TO VARYING DEGREES SHOWING MUCH OF CENTRAL
AND EASTERN ARIZONA WITH RELATIVELY SPOTTY CAPE DISTRIBUTION. FURTHER
WEST...THE MOISTURE IS BETTER AND MODEL CAPE IS BETTER AS
WELL...THOUGH NOT TREMENDOUSLY. IN GENERAL...NAM IS QUITE A BIT MORE
GENEROUS THAN GFS WITH RAP IN BETWEEN. NAM LOOKS OVERDONE FOR THE
LOWER COLORADO RIVER VALLEY. WHERE THERE DOES SEEM TO BE SOME
AGREEMENT ON NOTABLE CAPE FOR OUR FORECAST AREA IS OVER RIVERSIDE
COUNTY AND PORTIONS OF LA PAZ. WILL CONTINUE TO EVALUATE THE NEED
FOR A FLASH FLOOD WATCH IN THOSE AREAS WITH JOSHUA TREE NATIONAL PARK
BEING MOST LIKLEY CANDIDATE. ELSEWHERE...WILL PLAN ON MAKING SOME
TWEAKS TO THE POPS TODAY TO DELAY ONSET FOR PHOENIX AREA AND TRIM
BACK OVER SOUTHERN GILA COUNTY.
&&
.PREVIOUS DISCUSSION ISSUED 341 AM MST/PDT...
PER 10Z IR SATELLITE IMAGERY AN MCV CONTINUES TO TRACK NORTHWARD
INTO SOUTHERN NEW MEXICO WITH DEBRIS CLOUDS EXPANDING WESTWARD ACROSS
CENTRAL ARIZONA AND SOUTHERN NEVADA. WITH THE SHORTWAVE MOVING TO THE
NORTHEAST AROUND THE HIGH PRESSURE...SOUTHEASTERLY FLOW CONTINUES TO
BRING MOISTURE /MIXING RATIOS 12-15 G/KG/ INTO SOUTHERN AND CENTRAL
ARIZONA. DEWPOINT READINGS THIS MORNING CONTINUE TO BE ELEVATED INTO
THE MID 60S. TEMPERATURES ARE RUNNING ABOUT 1-3 DEGREES COOLER THAN
THIS TIME YESTERDAY...LIKELY DUE TO LESS CLOUD COVER. THAT BEING
SAID...EXPECTING TO HAVE A BIT LONGER PERIOD OF CLEARING SKIES AND
MORE DAYTIME HEATING TODAY...AND THUS RAISED TEMPERATURES TODAY.
TODAY`S STORM CHANCES LOOK TO BE MORE DIURNALLY DRIVEN...FOCUSING ON
THE AFTERNOON AND EARLY EVENING HOURS FOR MOST OF CENTRAL AND
SOUTHWEST ARIZONA. DIFFLUENT MID TO UPPER LEVEL FLOW ASSOCIATED WITH
THE INVERTED TROUGH CIRCULATING AROUND THE HIGH WILL FOCUS THE
INSTABILITY ACROSS SOUTHEAST CALIFORNIA THIS MORNING INTO EARLY
AFTERNOON...WHERE THE BRUNT OF THE MOISTURE IS BEING HOUSED. NOTHING
OUTSTANDING WITH PWAT VALUES /1.7 - 1.8 INCH OUT OF YUMA/ NEARING
THE 90TH PERCENTILE FOR THE LOWER COLORADO RIVER VALLEY AND
SOUTHEAST CALIFORNIA. WITH DAYTIME HEATING AND INCREASED
MOISTURE...THE LACKING INGREDIENT WILL BE STRONG LIFT. MARGINAL
INSTABILITY WITH A WEAK STEERING FLOW AND DYNAMIC FEATURE DOES NOT
LOOK TOO PROMISING FOR AN OVERLY ACTIVE DAY ACROSS SOUTHEAST
CALIFORNIA...THOUGH NOT RULING OUT ALL ACTIVITY...AND THUS HAVE
DECIDED NOT TO ISSUE ANY HYDRO PRODUCT AT THIS TIME. FRIDAY`S
OUTLOOK IS MUCH OF THE SAME AS TODAY...THOUGHT WITH SLIGHTLY LESS
MOISTURE IN THE LOWER LEVELS...SO EXPECTING MOST OF THE CONVECTIVE
ACTIVITY TO REMAIN ACROSS EASTERN AND EAST CENTRAL ARIZONA.
WHILE A RIDGE OF HIGH PRESSURE REMAINS EVIDENT AND IN FAIR LOCATION
THROUGH THE WEEK AHEAD...THE WIND FLOW PATTERN SHIFTS SLIGHTLY TO A
SOUTHWESTERLY DIRECTION AND LOSES SOME OF THE PROPER MOISTURE. IN
COMPARISON TO CURRENT MIXING RATIOS OF 10-12 G/KG...BY MONDAY THE
VALUES ARE FORECAST TO DROP BELOW 8 G/KG AND A MORE CONFLUENT
LAMINAR FLOW SETTLES IN. NOTHING IN THE PATTERN AHEAD SHOWS A GREAT
DEAL OF PROMISING CONVECTIVE ACTIVITY AND LOOKS TO BE MORE OF A
PERSISTENT MILD MONSOON PATTERN...WITH MINIMALLY FLUCTUATING
TEMPERATURES AND STORM CHANCES EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SCT-BKN DEBRIS CLOUDS TO LINGER INTO A PORTION OF THE AM HOURS...
WHILE GRADUALLY THINNING AND CLEARING TOWARDS THE AFTN. EASTERLY SFC
WINDS WILL TRANSITION TO WESTERLY HEADINGS FOR THE AFTN...WITH A
WINDOW OF LIGHTER VRB HEADINGS AROUND MIDDAY. THUNDERSTORMS EXPECTED
TO DEVELOP AGAIN OVER PORTIONS OF THE HIGHER TERRAIN NORTH...EAST...
AND SOUTHEAST OF THE PHX AREA. CHANCES LOOK GOOD FOR OUTFLOW
INTRUSIONS INTO THE METRO POST 31/00Z...PSBLY FROM THE NORTH OR
SOUTHEAST. CANNOT RULE OUT A VCSH POP-UP ALONG THOSE
BOUNDARIES...SO INCLUDED VCSH MENTION FOR KIWA AND KSDL 31/03-04Z
TIME FRAME.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
CLEARING SKIES SO FAR THIS MORNING AND MOSTLY CLEAR SKIES UPSTREAM
SHOULD ALLOW FOR AMPLE DAYTIME HEATING AND PTNL FOR AT LEAST
ISOLATED THUNDERSTORMS ACROSS SOUTHEAST CA...PARTICULARLY NEAR KBLH.
INCLUDED AFTN VCTS COVERAGE FOR KBLH. SFC WINDS TO MAINTAIN SOME
SOUTHERLY ORIENTATION DURING MUCH OF THE DAY WITH SPEEDS GNLY LESS
THAN 10 KTS...WITH PTNL FOR GUSTY WINDS AND DRASTIC WIND SHIFTS FROM
NEARBY THUNDERSTORMS AND LONG-TRAVELING OUTFLOWS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
MONSOONAL MOISTURE WILL SLOWLY BEGIN TO THIN ACROSS THE AREA...FIRST
ACROSS THE WESTERN FIRE DISTRICTS AND EVENTUALLY INTO THE ENTIRE
LOWER DESERT ELEVATIONS AND REGION BY EARLY NEXT WEEK. THIS WILL
RELEGATE STORM CHANCES BACK TOWARDS THE HIGHER TERRAIN AND FURTHER
TO THE EAST ACROSS AZ. THE SLIGHTLY DRIER AIRMASS AND BUILDING UPPER
RIDGE HEIGHTS WILL LEND THEMSELVES TOWARD WARMER SFC CONDITIONS...AT
OR ABOVE SEASONAL NORMALS. WINDS WILL FOLLOW FAMILIAR WARM SEASON
PATTERNS.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...DEWEY
AVIATION...NOLTE
FIRE WEATHER...NOLTE
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
946 AM PDT THU JUL 30 2015
.SYNOPSIS...
WARM AND HUMID TODAY WITH ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS OVER THE AREA. FLASH FLOOD WATCH FOR
MOUNTAINS/DESERTS/INLAND EMPIRE THROUGH THIS EVENING. DRIER...WITH
NEAR NORMAL HIGH TEMPERATURES...THIS WEEKEND INTO EARLY NEXT WEEK
AS HIGH PRESSURE BUILDS ALOFT. NIGHT/MORNING LOW CLOUDS ALONG THE
COAST AND BREEZY WESTERLY WIND THROUGH MOUNTAIN PASSES AND ALONG
DESERT MOUNTAIN SLOPES THROUGH THE PERIOD.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
AT 9 AM PDT...WATER VAPOR SATELLITE IMAGERY DISPLAYED A BROAD
UPPER-LEVEL RIDGE STRETCHING FROM THE LOWER MISSISSIPPI VALLEY TO
CENTRAL NEVADA...AND A WEAK UPPER-LEVEL LOW AROUND 200 MILES SSW
OF SAN DIEGO. THE 30/1200 UTC KNKX SOUNDING DISPLAYED A VERY MOIST
AND UNSTABLE PROFILE...WITH A CALCULATED PRECIPITABLE WATER OF
2.02 INCHES AND MOST-UNSTABLE CAPE OF 2030 J/KG. A WEAK UPPER-
LEVEL WAVE MOVING ACROSS THE REGION WAS GENERATING LIGHT SHOWERS
OVER PORTIONS OF THE SAN BERNARDINO COUNTY MOUNTAINS AND DESERTS.
WITH DIURNAL HEATING...CONDITIONS SHOULD COME TOGETHER LATE THIS
MORNING THROUGH THIS EVENING TO GENERATE SHOWERS AND THUNDERSTORMS
OVER THE REGION...MAINLY OVER THE DESERTS...MOUNTAINS AND THE
INLAND EMPIRE. THE 30/1500 UTC HRRR SHOWS SHOWER AND THUNDERSTORM
ACTIVITY DEVELOPING OVER THE SAN DIEGO AND RIVERSIDE COUNTY
MOUNTAINS AROUND NOON...THEN DEVELOPING OVER PORTIONS OF SW SAN
BERNARDINO COUNTY LATER THIS AFTERNOON AS CLOUDS CLEAR THE AREA.
THIS WILL LIKELY BE THE CASE GIVEN MODERATE NEGATIVE VORTICITY
ADVECTION IN THE WAKE OF THE UPPER-LEVEL WAVE MOVING OUT OF THE
AREA THIS MORNING. IF ANY OF THESE STORMS BECOME STATIONARY...OR
TRAIN OVER A LOCATION...THERE IS A GOOD POTENTIAL FOR FLASH
FLOODING. HOWEVER...MOST STORMS ARE EXPECTED TO MOVE AROUND 15 MPH
GIVEN THE MID AND UPPER-LEVEL WINDS. THE FLASH FLOOD WATCH FOR THE
MOUNTAINS...DESERTS AND INLAND EMPIRE REMAINS IN EFFECT THROUGH 8
PM PDT THIS EVENING. A WEAK UPPER-LEVEL WAVE MOVING ACROSS THE
REGION TONIGHT WILL CREATE THE POSSIBILITY OF AN ISOLATED
SHOWER/THUNDERSTORM OVER THE MOUNTAINS AND DESERTS.
ON FRIDAY...FLOW WILL SHIFT FROM SE TO MORE SOUTHERLY...ADVECTING
DRIER AIR INTO THE REGION. THIS WILL CREATE LESS OF A FLASH FLOOD
THREAT AND LOWER THE COVERAGE OF AFTERNOON THUNDERSTORMS COMPARED
TO TODAY. MODELS ARE TRENDING DRIER FOR THE WEEKEND INTO EARLY
NEXT WEEK AS THE AFOREMENTIONED UPPER-LEVEL RIDGE BUILDS TO THE
SE. WILL WAIT FOR THE 12 UTC MODEL RUNS BEFORE CHANGING THE POP
FORECAST. HOWEVER...CONFIDENCE IS INCREASING FOR DRY WEATHER FOR
THE WEEKEND THROUGH NEXT TUESDAY. THE 30/0600 GFS BRINGS MOISTURE
BACK INTO THE AREA NEXT WEDNESDAY...AND GENERATES THUNDERSTORMS
OVER THE MOUNTAINS AND DESERTS NEXT WEDNESDAY AND THURSDAY.
BUILDING HEIGHTS OVER THE AREA WILL HELP RAISE HIGH TEMPERATURES
TO NEAR NORMAL...AND MAINTAIN A SHALLOW MARINE LAYER WITH PATCHY
NIGHT/MORNING LOW CLOUDS/FOG ALONG THE COAST AND COASTAL VALLEYS.
NORMAL ONSHORE PRESSURE GRADIENTS WILL CREATE BREEZY WESTERLY
WINDS THROUGH MOUNTAIN PASSES AND ALONG DESERT MOUNTAIN SLOPES IN
THE AFTERNOONS/EVENINGS THROUGH THE PERIOD.
&&
.AVIATION...
301530Z...COAST/VALLEYS...SCT-BKN LOW CLOUDS PERSIST
OVER THE COASTAL BASIN AND INLAND IN/NEAR KCRQ WITH BASES NEAR 1500
FT MSL AND TOPS 2000 FT MSL. THE LOW CLOUDS WILL ERODE THE COAST
BETWEEN 30/1500-1800Z. THERE IS A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH THIS EVENING ACROSS THE ENTIRE REGION...THOUGH
THE MOUNTAINS WILL BE FAVORED. HOWEVER...CONFIDENCE ON TIMING IS LOW
SO WILL MONITOR FOR VCTS INCLUSION IN THE TAFS. STRATUS WITH SIMILAR
BASES AND HEIGHTS AS THIS MORNING WILL PUSH BACK INLAND AFTER
31/0300Z.
MTNS/DESERTS...A CHANCE OF SHOWERS AND THUNDERSTORMS EXISTS THROUGH
THIS EVENING ACROSS THE MTS AND DESERTS. GREATEST STORM COVERAGE
WILL BE AFT 30/2000Z. THUNDERSTORM BASES WILL GENERALLY BE AOA 8000
FT MSL WITH TOPS TO 40000 FT MSL. THE MAIN THREATS FROM THESE STORMS
WILL BE BRIEF HEAVY RAIN...LOWERED VIS...AND FREQUENT CLOUD-TO-CLOUD
AND CLOUD-TO-GROUND LIGHTNING.
&&
.MARINE...
830 AM...THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS OVER
THE INNER COASTAL WATERS THROUGH THIS EVENING AS AN UPPER LEVEL
DISTURBANCE MOVES OVER THE AREA. OTHERWISE...NO HAZARDOUS MARINE
WEATHER IS EXPECTED THROUGH SUNDAY.
&&
.BEACHES...
830 AM...THE ELEVATED SURF WILL SUBSIDE TODAY AS THE
SWELL DECLINES TO AROUND 2 FT AT 14-15 SEC...BUT THE RISK OF STRONG
RIP CURRENTS AND LIGHTNING CONTINUES THROUGH THE EVENING. THEREFORE
THE BEACH HAZARDS STATEMENT WILL CONTINUE THROUGH THIS EVENING. THE
SLOW DOWNWARD TREND IN THE SWELL WILL CONTINUE THROUGH THE
WEEKEND.
&&
.SKYWARN...
SKYWARN ACTIVATION MAY BE REQUESTED LATER TODAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...FLASH FLOOD WATCH UNTIL 8 PM PDT THIS EVENING FOR APPLE AND
LUCERNE VALLEYS-COACHELLA VALLEY-RIVERSIDE COUNTY MOUNTAINS-
SAN BERNARDINO COUNTY MOUNTAINS-SAN BERNARDINO AND
RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN DIEGO COUNTY
DESERTS-SAN DIEGO COUNTY MOUNTAINS-SAN GORGONIO PASS NEAR
BANNING.
BEACH HAZARDS STATEMENT UNTIL 8 PM PDT THIS EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...NONE.
&&
$$
PUBLIC...JJT
AVIATION/MARINE/BEACHES...TS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1012 AM MDT THU JUL 30 2015
.UPDATE...
ISSUED AT 1012 AM MDT THU JUL 30 2015
NO CHANGES TO THE FORECAST NEEDED AT THIS TIME. MODELS ARE RATHER
TENTATIVE IN GENERATING MUCH QPF ACROSS NORTHEAST COLORADO THIS
AFTERNOON AND EVENING. THE AXIS OF THE UPPER RIDGE APPEARS TO
STILL BE SOUTH OF US WITH THE DEEPER MONSOONAL MOISTURE BEING HELD
SOUTH OF THAT FEATURE. FLOW ALOFT OVER OUR FORECAST AREA IS WEAK
AND NORTHWESTERLY...REMAINING DRIER AND MORE STABLE. SINCE SOME OF
THE MOISTURE HAS MADE IT INTO SOUTHERN COLORADO...WILL HOLD ON TO
THE LOW CHANCES OF AFTERNOON SHOWERS OVER PARK COUNTY AND THE
PALMER DIVIDE.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 345 AM MDT THU JUL 30 2015
BROAD HIGH PRESSURE ALOFT CONTINUES ACROSS THE SOUTHERN TIER
STATES...WITH SOME BUILDING OF THE HIGH FURTHER WEST AND NORTH ACROSS
THE GREAT BASIN. THIS WILL KEEP SOME DRIER...WESTERLY FLOW ACROSS
NORTHERN COLORADO...WHILE SOUTHERN COLORADO REMAINS UNDER A
WETTER...SOUTHWEST FLOW. HIGHER POPS TODAY AGAIN WILL REMAIN OVER
SOUTHERN PORTIONS OF CWA...ESPECIALLY OVER PARK COUNTY AND
EXTENDING FURTHER EAST ACROSS THE PALMER DIVIDE. SURFACE TROF OVER
EASTERN COLORADO BECOMES ELONGATED ACROSS NORTHEAST COLORADO WHICH
RESULTS IN SOME WEAK CONVERGENCE FROM THE PALMER DIVIDE AND
STRETCHES THROUGH FAR NE PLAINS. IN ADDITION...JET STREAK ACROSS
THE MIDWEST MAY PRODUCE SOME WEAK LIFT OVER THE PLAINS AS WELL.
INDEED...THE RAP DOES SOME HAVE SOME WEAK LIFT IN THE 700MB QG
VERTICAL VELOCITY FIELD.
TEMPERATURES TODAY WILL BE A FEW DEGREES HIGHER TODAY OVER
NORTHERN SECTIONS WITH THE DRIER AND SLIGHTLY WARMER AIRMASS. MAIN
CHANGE WAS TO EXTEND POPS A BIT FURTHER NORTH ON THE FAR PLAINS
THROUGH THIS EVENING.
SATELLITE IMAGERY THIS MORNING SHOWING SOME STRATUS AND POTENTIAL
FOG DEVELOPING OVER LINCOLN COUNTY AND WILL TO TO GRIDS TO COVER
THIS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT THU JUL 30 2015
MODELS ARE STILL IN AGREEMENT AS THEY CONTINUE TO EXTEND THE
UPPER RIDGE NORTHWESTWARD ACROSS THE NORTHERN GREAT BASIN PLACING
NERN COLORADO UNDER A SOMEWHAT DRIER NWLY MID-LEVEL FLOW FRIDAY
MORNING. MEANWHILE SUBTROPICAL MOISTURE POOLING ACROSS NORTHERN
NEW MEXICO/NERN ARIZONA IS FORECAST TO FLOW NORTHWARD INTO SRN
COLORADO EARLY IN THE DAY AND UP ALONG THE NORTHERN FRONT RANGE
DURING THE AFTERNOON. DAYTIME HEATING COUPLED WITH THE INCREASE
IN PRECIPITABLE WATER SHOULD MANAGE TO PRODUCE SCATTERED T-STORMS
OVER THE FRONT RANGE MTNS DURING THE AFTERNOON AND POSSIBLY AS
EARLY AS LATE MORNING OVER THE MOSQUITO RANGE AND SOUTH PARK IN
PARK COUNTY. NWLY TRANSPORT WINDS SHOULD THEN MOVE THESE STORMS
OVER THE ADJACENT HIGH PLAINS DURING THE MID AND LATE AFTERNOON
HRS WHERE THEY SHOULD LINGER THRU MID-EVENING PRODUCING GUSTY
WINDS AND BRIEF LIGHT TO MODERATE RAINFALL. PRECIP CHANCES IN THE
30-40 PCT RANGE IN THE HIGH COUNTRY AND 10-20 PCT AT LOWER
ELEVATIONS. THE PRESENCE OF A STRONG MID-LEVEL CAP SHOULD HINDER
THE FORMATION OF DEEP UPDRAFTS AND THEREFORE STORMS SHOULD STAY
WELL BELOW SEVERE CRITERIA. HIGHS ON FRIDAY STILL BELOW AVERAGE
WITH MID/UPPER 80S WITH MAINLY 70S IN THE HIGH COUNTRY.
LOOKING AHEAD TO THE WEEKEND...THE NEGATIVELY TILTED UPPER RIDGE
OVER THE WESTERN CONUS CONTINUES TO BUILD NORTHWARD ON SATURDAY
WHICH PUSHES THE SUBTROPICAL MOISTURE PLUME SOUTHWARD RESULTING IN
DRIER AND WARMER CONDITIONS FOR THE CWA. THEREFORE SHOULD SEE LESS
STORM ACTIVITY ON SATURDAY...WITH THE BEST CHANCE FOR STORMS OVER
THE HIGHER TERRAIN SOUTH OF INTERSTATE 70. ON SUNDAY...THE UPPER
RIDGE SHIFTS EAST WITH LIGHT W-NWLY FLOW MOVING OVER THE FCST AREA.
SUBTROPICAL MOISTURE TRAPPED BENEATH THE RIDGE REVERSES ITS COURSE
AND BEGINS FLOWING NORTHWARD ACRS COLORADO. SHOULD SEE A FEW MORE T-
STORMS IN THE HIGH COUNTRY WITH ONLY A SLIGHT CHANCE ON THE NEARBY
PLAINS. HIGHS ON SUNDAY CREEP UP TO NEAR ABOVE AVERAGE.
MONDAY THROUGH WEDNESDAY...THE UPPER RIDGE IS STILL PROGGED TO
REMAIN OVER THE ROCKY MTN REGION WITH LITTLE DAY-TO-DAY CHANGE IN
WEATHER. ALTHOUGH THE ECMWF SHOWS A RATHER VIGOROUS SHORTWAVE
ROTATING ACROSS THE STATE ON MONDAY. THIS IS NEW IN THE MODEL. SO
WILL NOT BASE TOO MUCH OF THE FCST ON THIS FEATURE AT THE PRESENT
TIME. EXPECT TEMPERATURES TO RANGE FROM NEAR TO SLIGHTLY ABOVE
AVERAGE DURING THE PERIOD...WITH A CHANCE OF AFTERNOON AND EVENING T-
STORMS MAINLY IN AND NEAR THE MTNS EACH DAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1012 AM MDT THU JUL 30 2015
MINIMAL AVIATION IMPACTS EXPECTED THROUGH THIS AFTERNOON. SHOWERS
AND THUNDERSTORMS ARE EXPECTED TO BE SOUTH OF THE DENVER
AREA...POSSIBLY OVER THE PALMER DIVIDE. SURFACE PRESSURE GRADIENTS
HAVE RELAXED OVER THE PAST 24 HOURS...LEADING TO LESS
SOUTHEASTERLY WINDS TODAY. STILL EXPECT WINDS TO BECOME MORE
EASTERLY DURING THE AFTERNOON HOURS. CHANCES OF SHOWERS OVER THE
DENVER AIRPORTS ARE SO LOW THAT THEY ARE NOT GOING TO BE MENTIONED
IN THE TAFS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DANKERS
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS ALBANY NY
423 PM EDT THU JUL 30 2015
.SYNOPSIS...
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO THE EARLY EVENING HOURS. BEHIND
THIS BOUNDARY...LESS HUMID AIR WILL MOVE INTO THE AREA FOR TONIGHT
INTO FRIDAY...ALTHOUGH TEMPERATURES WILL CONTINUE TO BE WARM ON
FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN ON
SATURDAY...WITH TEMPERATURES SLIGHTLY ABOVE NORMAL LEVELS.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 423 PM EDT...COLD FRONT IS IN THE PROCESS OF MOVING ACROSS
THE CWA. THE BOUNDARY IS ALREADY THROUGH THE WESTERN AND CENTRAL
PARTS OF THE REGION. WINDS HAVE SWITCHED TO THE W-NW BEHIND THE
BOUNDARY...INCLUDING THE CAPITAL REGION...AND DEWPOINTS ARE
SLOWING STARTING TO FALL.
MEANWHILE...ALONG AND AHEAD OF THE BOUNDARY...SOME SHOWERS AND
THUNDERSTORMS ARE STILL ONGOING. THE STEADIEST/HEAVIEST
THUNDERSTORM ACTIVITY IS SOUTH OF THE AREA OVER THE LOWER HUDSON
VALLEY...AND COASTAL AND CENTRAL CT. HOWEVER...SOME ACTIVITY
CONTINUES OVER DUTCHESS/LITCHFIELD COUNTIES...AND SOME ADDITIONAL
ISOLATED TO SCATTERED SHOWERS/THUNDERSTORMS ARE POSSIBLE ALONG THE
IMMEDIATE FRONTAL BOUNDARY OVER THE NEXT FEW HOURS...AS IT
CONTINUES TO SLOWLY SETTLE SOUTH AND EAST. THE 3KM HRRR SUGGEST
THIS WILL CONTINUE TO BE A POSSIBILITY FOR THESE FAR SOUTHEASTERN
AREAS TILL ABOUT 8 TO 10 PM...WHEN FINALLY THE FRONT WILL BE
THROUGH THE REGION.
BEHIND THE FRONT...DEWPOINTS WILL CONTINUE TO FALL OVERNIGHT WITH
DECREASING CLOUDS. SOME PATCHY FOG WILL BE POSSIBLE...ESP FOR
SOUTHERN AND EASTERN AREAS WHERE THE FRONT WILL MOVE THROUGH
LAST...AS WELL AS ACROSS AREAS THAT SAW SIGNIFICANT RAINFALL ON
THURSDAY AS WELL.
MIN TEMPS LOOK TO BE IN THE UPPER 50S TO MID 60S IN MANY
AREAS...ALTHOUGH TEMPS WILL BE SLIGHTLY COOLER OVER THE
ADIRONDACKS AND SRN GREENS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
QUIET WEATHER IS EXPECTED FOR FRIDAY AS HIGH PRESSURE OVER THE
OHIO VALLEY AND MID ATLANTIC REGION NOSES INTO THE REGION. SKIES
WILL BE PARTLY TO MOSTLY SUNNY AND TEMPS LOOK WARM IN THE 80S. IT
WILL BE NOTICEABLY LESS HUMID AS WELL WITH DEWPOINTS ONLY IN THE
50S AS WELL.
AN UPPER LEVEL DISTURBANCE WILL START APPROACHING THE AREA FOR
FRIDAY NIGHT. IT SHOULD REMAIN DRY FOR MOST AREAS...ALTHOUGH
CANNOT RULE OUT A SHOWER OVER THE ADIRONDACKS FOR LATE FRI NIGHT.
MIN TEMPS LOOK TO BE IN THE MID 50S TO MID 60S.
SHORTWAVE TROUGH WILL BE SITUATED OVER THE NORTHEAST FOR SATURDAY
WITH A SFC FRONTAL BOUNDARY MOVING ACROSS THE AREA AS WELL. THERE
WILL BE A CHANCE FOR SHOWERS AND THUNDERSTORMS DURING THE DAY WITH
THE PASSAGE OF THIS BOUNDARY...ESP FOR NORTHERN AREAS. HIGHS TEMPS
LOOK TO BE IN THE 80S...WITH SOME 70S OVER THE HIGHER ELEVATIONS.
INSTABILITY MAY BE SOMEWHAT LIMITED TO CLOUDS AROUND AND TIMING
OF THE FRONT MAY NOT BE IDEAL FOR SEVERE STORMS TO OCCUR...ALTHOUGH
WILL CONTINUE TO MONITOR MODEL TRENDS.
THE SHORTWAVE SHOULD BE MOVING AWAY FOR SAT NIGHT...SO CLEARING
LOOKS TO OCCUR WITH ANY SHOWERS/THUNDERSTORMS ENDING DURING THE
EVENING HOURS. TEMPS LOOK TO FALL IN THE MID 50S TO LOW 60S
ACROSS THE REGION.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
IT STILL LOOKS AS IF A LONG WAVE TROUGH WILL BE DEVELOPING DURING
THE EXTENDED PERIOD OVER THE EASTERN CONUS. THIS DEEPENING TROUGH
WILL COMPROMISE OF A SERIES OF SHORT WAVES...DIVING FROM CENTRAL
CANADA TO THE MID ATLANTIC REGION. THE SPECIFIC TIMING OF THESE
SHORT WAVES IS DIFFICULT AT THIS TIME.
SUNDAY...THE FIRST OF THESE SHORT WAVES AND ASSOCIATED FRONTAL
BOUNDARY WILL BRUSH OUR REGION LATE INTO THE DAY AND EARLY EVENING
(MAINLY STAYING NORTH OF FORECAST AREA). WE KEPT SLIGHT TO LOW
CHANCES FROM THE CAPITAL REGION NORTHWESTWARD...NO POPS SOUTHEAST OF
THE CAPITAL REGION.
A STRONGER DISTURBANCE AND EVENTUALLY COLD FRONT IS FORECAST TO
APPROACH ON MONDAY OR MONDAY NIGHT. THIS COULD PACK MORE OF PUNCH
WITH MORE IN THE WAY OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS
MOST AREAS BY MONDAY NIGHT.
IT LOOKS AS IF PUSH OF SIGNIFICANTLY COOLER AIR WILL INFILTRATE
BEHIND THE COLD FRONT (OR SERIES OF COLD FRONTS) LATE TUESDAY AS
H850 TEMPERATURES LOOK TO GET PUSHED FROM TYPICAL MID TEENS VALUES
OF EARLY AUGUST...TO ABOUT +6C! THIS COOLING WILL PRODUCE INCREASED
LOW LEVEL INSTABILITY WHICH COULD TRIGGER SOME ADDITIONAL SHOWERS AND
PERHAPS A THUNDERSTORM ON TUESDAY INTO TUESDAY EVENING.
WEDNESDAY WILL BE NOTICEABLY COOLER AND WITH THE COLD POOL
ALOFT...THERE STILL COULD BE ADDITIONAL INSTABILITY SHOWERS...MAINLY
ACROSS THE ADIRONDACKS.
BY THURSDAY THE 12Z ECMWF STILL INDICATED A WAVE ALONG THE FRONT
ACROSS THE MID ATLANTIC REGION...PRODUCING A BAND OF RAIN ACROSS
MAINLY OUR SOUTHERN AREAS. THIS IDEA IS NOT SUPPORTED BY THE 12Z GFS
SO FOR NOW...ONLY INCLUDED A 20 PERCENT CHANCE OF SHOWERS (SLIGHT).
HIGH TEMPERATURES WILL START OUT WITH SEASONABLE READINGS FROM THE
UPPER 70S TO MID 80S ACROSS MOST OF OUR AREA SUNDAY THROUGH TUESDAY
WITH LOWS RANGING FROM MID 50S TO MID 60S. HOWEVER...BY WEDNESDAY
AND THURSDAY...HIGH TEMPERATURES WILL ONLY RANGE FROM THE UPPER 60S
ACROSS THE ADIRONDACKS...TO 70S ACROSS MOST OF THE REMAINDER OF THE
REGION. LOWS WILL DIP INTO THE 50S...WITH SOME UPPER 40S IN THE
COOLEST SPOTS WELL AWAY FROM THE HUDSON VALLEY.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
BROAD AREA OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WAS MAKING
ITS WAY SOUTHEAST ACROSS KGFL AND KALB AT 1730Z. EXPECTING ACTIVITY
TO CLEAR OUT OF THESE TWO AIRPORTS AROUND 18Z...PUT POPCORN SHOWERS
WILL LINGER WITH WHAT LEFTOVER DAYTIME HEATING INTERACTS WITH SLOWLY-
DEPARTING MOISTURE AT THE LOW AND MID LEVELS...CARRYING JUST VCSH
FOR THIS.
AT KPSF...AND PARTICULARLY AT KPOU...THUNDERSTORMS STARTING
SHORTLY AFTER 18Z AS CELLS WITHIN RAIN AREA GAIN A LITTLE
STRENGTH...SHOULD LAST TIL 20Z. COLD FRONT LAGS BEHIND A COUPLE OF
HOURS...THEN THINGS IMPROVE MORE...ESPECIALLY AROUND
SUNSET...UNTIL MVFR/IFR FOG DEVELOPS AT THE AIRPORTS DURING THE
LATE OVERNIGHT.
WINDS WILL PICK UP BRIEFLY BEHIND THE FRONT...WITH LIGHT WINDS THEN
ALLOWING FOR THE FOG...WHICH WILL BURN OFF QUICKLY AFTER SUNRISE DUE
TO LACK OF CLOUD COVER AND EARLY MIXING. THROUGH THE COLUMN...SPEED
SHEAR IS JUST ENOUGH AT KGFL AND KALB TO INCLUDE WS FOR THE EVENING/
OVERNIGHT PERIOD.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT FEW DAYS. MANY AREAS SAW A
WETTING RAINFALL ON THURSDAY. A FEW MORE LINGERING SHOWERS OR
THUNDERSTORMS ARE POSSIBLE OVER SOUTHERN AREAS THIS
EVENING...OTHERWISE DRY WEATHER LOOKS TO RETURN FOR TONIGHT
THROUGH TOMORROW NIGHT. SOME SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
AFTER RH VALUES RETURN TO NEAR 100 PERCENT TONIGHT...THEY ARE
EXPECTED TO DROP TO 35 TO 45 PERCENT ON FRIDAY AFTERNOON WITH WEST
WINDS OF 10 TO 15 MPH. RH VALUES LOOK TO RETURN TO AROUND 100
PERCENT ON FRI NIGHT. RH VALUES WILL DROP TO 40 TO 50 PERCENT ON
SAT AFTN WITH S-SW WINDS AT 5 TO 10 MPH.
&&
.HYDROLOGY...
NO MAIN STEM RIVER FLOODING IS FORECAST THROUGH THE NEXT FIVE DAYS.
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME LINGERING
SHOWERS OR THUNDERSTORMS ARE ONGOING OVER THE MID HUDSON VALLEY
AND WESTERN NEW ENGLAND FOR THE LATE AFTN THROUGH THE EARLY
EVENING HOURS. WITH A HUMID AIR MASS IN PLACE...AND THE SHOWERS
AND THUNDERSTORMS MOVING RATHER SLOWLY...LOCALLY HEAVY DOWNPOURS
MAY ALLOW FOR SOME MINOR FLOODING OF URBAN OR POOR DRAINAGE AREAS.
ISOLATED FLASH FLOODING IS POSSIBLE OVER THE NEXT FEW HOURS...BUT
IS NOT EXPECTED TO BE WIDESPREAD...AS THE BOUNDARY SHOULD BE
CROSSING THE ENTIRE AREA SOON.
MAINLY DRY WEATHER WILL RETURN FOR TONIGHT THROUGH FRIDAY NIGHT.
SOME ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
FOR SATURDAY INTO EARLY NEXT WEEK. WIDESPREAD HEAVY RAIN ISN/T
EXPECTED...BUT ANY THUNDERSTORM IS CAPABLE OF PRODUCING LOCALLY
HEAVY DOWNPOURS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...HWJIV
AVIATION...ELH
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
353 PM EDT THU JUL 30 2015
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING WILL GIVE WAY
TO DRIER WEATHER FRIDAY...BUT IT WILL REMAIN VERY WARM. WARM AND
HUMID CONDITIONS WILL RETURN THIS WEEKEND...THEN WILL BECOME LESS
HUMID WITH TEMPERATURES CLOSER TO NORMAL NEXT WEEK. THERE IS A LOW
RISK FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THIS WEEKEND
INTO EARLY NEXT WEEK...HOWEVER MUCH OF THE TIME DRY WEATHER WILL
PREVAIL.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
355 PM UPDATE...
* LINE OF STRONG TO POSSIBLY SEVERE STORMS THRU 9 PM *
* LOCALIZED WIND DAMAGE/FLOODING AND PERHAPS AN ISOLATED TORNADO
MESOANALYSIS SHOWS 1500-2000 K/KG OF SB CAPE ACROSS SOUTHERN NEW
ENGLAND WITH 25KT OF 0-6KM SHEAR BUT MEAGER MID LEVEL LAPSE RATES.
LINE OF STORMS HAS BECOME MORE ORGANIZED FROM SW MA ACROSS CT AND
INTO NYC AREA. SO FAR HEAVY RAIN HAS BEEN MAIN THREAT BUT
OCCASIONALLY WE HAVE SEEN HIGHER CORES DEVELOP IN SOME OF THE
STORMS...SO POTENTIAL FOR LOCALIZED WIND DAMAGE AND FLOODING WILL
CONTINUE INTO THIS EVENING.
FOCUS FOR STORMS LOOKS TO BE ACROSS CT...NORTHERN RI AND CENTRAL/
EASTERN MA PER HIGH-RES MODELS. IN PARTICULAR HRRR SHOWS EVOLUTION
NICELY ALTHOUGH ITS TIMING IS A COUPLE OF HOURS TOO SLOW. LINE
SHOULD REACH PROVIDENCE/BOSTON CORRIDOR 6-7 PM.
ALTHOUGH VERY LOW PROBABILITY...STILL CANNOT RULE OUT AN ISOLATED
TORNADO PRIMARILY AS FAR E AS WORCESTER HILLS. PRESENCE OF
30-35KT WINDS AT 925 MB AND LOW LCL FROM 70+ DEWPOINTS POINTS
TOWARD THAT POTENTIAL. IF ONE DOES OCCUR... AND THAT IS A BIG
IF...IT WOULD LIKELY BE TOWARD WEAKER SIDE GIVEN STRENGTH OF WIND
FIELDS ALOFT.
ACTIVITY DIMINISHES TONIGHT WITH LOSS OF DAYTIME HEATING AND
PASSAGE OF COLD FRONT. EXPECT PATCHY FOG TO DEVELOP OVERNIGHT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRONT WILL BE OFFSHORE FRI MORNING WITH DRIER AND MORE COMFORTABLE
AIRMASS IN ITS WAKE. KEEPING FRI NIGHT DRY ALTHOUGH WE SHOULD SEE
INCREASING CLOUDS AS NEXT SHORT WAVE APPROACHES.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...
* EXPECT MORE SEASONABLE TEMPS AND LOWER HUMIDITY THROUGH MOST OF
THIS PERIOD
* CHANCE FOR A FEW SHOWERS/ISOLATED THUNDER EACH DAY BUT MUCH OF THE
TIME REMAINING DRY
SYNOPTIC OVERVIEW AND MODEL PREFERENCES...
MEDIUM RANGE FORECAST CONTINUES TO FEATURE ANOMALOUS H5 CUTOFF
VORTEX ACROSS JAMES AND HUDSON BAYS WHICH WILL ELONGATE ACROSS
QUEBEC DURING THE LONG TERM PERIOD. WILL STILL SEE LONG WAVE TROUGH
ACROSS THE EASTERN GREAT LAKES AND DOWN THE APPALACHIANS WHICH WILL
TEND TO FLATTEN...THOUGH SHORT WAVES WILL ROTATE AROUND THE BASE OF
THE CUTOFF LOW INTO THE MEAN TROUGH. THIS WILL BRING PERIODS OF
SHOWERS/THUNDERSTORMS ACROSS THE REGION FROM TIME TO TIME. NOT
EXPECTED A TOTAL WASHOUT AT ANY TIME...THOUGH MODELS LOOK LIKE THEY
MAY HAVE SOME CONTINUITY WILL BE AROUND THE LATE MON/MON NIGHT AND
TUE NIGHT TIMEFRAMES. HOWEVER...OPERATIONAL MODEL SOLUTION SPREAD
DOES WIDENS OVER TIME AS ONE WOULD EXPECT ESPECIALLY THIS TIME OF
THE YEAR...SO CONFIDENCE IN SPECIFIC TIMING OF CONVECTION AND ANY
SHORT WAVE PASSAGE LOWERS.
USED A BLEND OF AVAILABLE GUIDANCE INTO MONDAY...THEN TRANSITIONED
OVER TO THE GFS AND EC ENS MEANS WHICH GAVE A BIT MORE CONTINUITY
WITH PREVIOUS FORECASTS.
DETAILS...
SATURDAY...MODELS CONTINUE TO PAINT A WEAK H5 SHORT WAVE IN THE MEAN
UPPER FLOW FOR LATER SAT INTO SAT NIGHT. LOOKS LIKE BEST INSTABILITY
AND MOISTURE...WHAT THERE IS OF IT...WILL BE ACROSS CENTRAL AND
WESTERN AREAS. ANOTHER QUESTION WILL BE WHETHER THERE WILL BE SOME
NOCTURNAL INSTABILITY SHOWERS/TSTMS ALONG THE S COAST WHERE HIGHEST
HUMIDITIES ARE IN PLACE. HAVE LEFT OUT FOR NOW...BUT IT IS SIGNALED
ON THE GFS MODEL.
HAVE GENERALLY SLIGHT CHANCE POPS GOING...BUT MAY SEE A LINE OF SCT
SHOWERS/TSTMS ACROSS CT VALLEY INTO CENTRAL MA/NE CT POSSIBLE DURING
THE LATE AFTERNOON/EARLY EVENING. EXPECT THE SHORT WAVE TO SHIFT E
AND WEAKEN SO PRECIP SHOULD ALSO WEAKEN OVERNIGHT.
HIGHS WILL GENERALLY BE IN THE 80S. IT WILL BE COOLER WELL INLAND
LATE SAT NIGHT WITH LOWS AROUND 60...RANGING TO AROUND 70 ALONG THE
S COAST...CAPE COD AND THE ISLANDS.
SUNDAY...WEAK SURFACE RIDGE BUILDS ACROSS SO EXPECT A MAINLY DRY
DAY. H85 TEMPS WILL BE FROM +15C TO +16C...WHICH WILL TRANSLATE TO
THE 80S FOR MOST AREAS...A BIT COOLER ALONG THE S COAST WITH THE S-
SW WINDS IN PLACE.
MONDAY...SOUTHWEST WIND FLOW REMAINS IN PLACE. MODELS SIGNALING A
POSSIBLE PRE FRONTAL TROUGH APPROACHING LATE MON OR MON NIGHT
/TIMING IN QUESTION/. MAY SEE WIDELY SCT SHOWERS/ISOLD TSTMS ACROSS
CENTRAL AND WESTERN AREAS...WITH THE BEST CHANCE ACROSS W MA AND W
HARTFORD COUNTY. WITH THE MILDER S-SW FLOW IN PLACE...EXPECT HIGHS
MAINLY IN THE 80S.
TUESDAY...W-SW FLOW ALOFT AS QUEBEC VORTEX BROADENS. ANOTHER SHORT
WAVE AND ASSOCIATED COLD FRONT LOOKS TO APPROACH LATE TUE INTO TUE
EVENING. GFS MOST AGGRESSIVE IN DIGGING H5 TROUGH TO THE W WHICH
WILL KEEP WARM AND HUMID AIR IN PLACE. HAVE CARRIED CHANCE POPS
ACROSS THE REGION...THEN SHOULD PUSH OFFSHORE TUE NIGHT.
WEDNESDAY-THURSDAY...A LOT OF QUESTIONS AS TO WHETHER FRONT WILL
STALL S OF NEW ENGLAND DURING THIS TIMEFRAME AND IF WAVES WILL MOVE
ALONG THIS FRONT. FOR NOW...HAVE CHANCE POPS MOVING ACROSS WED
NIGHT/THU...BUT TIMING IS STILL VERY MUCH IN QUESTION. LOW
CONFIDENCE DURING THIS TIMEFRAME DUE TO TIMING DIFFERENCES.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
HIGH CONFIDENCE THROUGH FRI NIGHT.
LINE OF SHOWERS/TSTMS WITH MVFR/IFR ARRIVE IN W NEW ENGLAND 18Z-
20Z AND SHOULD WEAKEN BEFORE REACHING COAST 21Z- 00Z. HEAVY RAIN
MAIN THREAT BUT POTENTIAL FOR 40-50KT GUSTS IN STRONGER STORMS. SW
WINDS GUST TO 25KT ESPECIALLY NEAR S COAST.
MVFR/IFR CIGS SHOULD RETURN TO PARTS OF A COAST...CAPE COD AND
ISLANDS THIS EVENING. COULD ALSO SEE PATCHY IFR DUE TO VALLEY FOG
INLAND. VFR FRI AND FRI NIGHT WITH W/SW WINDS...MAY HAVE LOCAL
SEA BREEZES DURING AFTERNOON NEAR COAST.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. MAIN WINDOW FOR TSTMS
22Z-00Z. HEAVY RAIN/LIGHTNING MAIN HAZARDS.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. MAIN WINDOW FOR TSTMS
THRU 21Z. 40KT GUSTS POSSIBLE IN STRONGER STORMS.
OUTLOOK /SATURDAY THROUGH TUESDAY/...MODERATE CONFIDENCE.
EXPECT GENERALLY VFR MOST OF THE TIME. LOW CHANCE OF SCT SHOWERS/
ISOLD THUNDERSTORMS SAT AFTERNOON/EARLY SAT NIGHT AND AGAIN MON-TUE.
BRIEF LOCAL MVFR IN ANY PRECIP.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
HIGH CONFIDENCE THROUGH FRI NIGHT.
SCA REMAINS POSTED FOR 20-30KT GUSTS THIS AFTERNOON NEAR SHORE AS
GRADIENT TIGHTENS AHEAD OF COLD FRONT. IN ADDITION...LONG
SOUTHWEST FETCH WILL ALLOW FOR SEAS TO BUILD TO BETWEEN 3 TO 5
FEET ACROSS MOST OPEN WATERS. WINDS DIMINISH THIS EVENING...BUT
KEEPING SCA THROUGH TONIGHT FOR THE OUTER WATERS DUE TO LEFTOVER
SWELL.
HIGH PRESSURE WILL BUILD OVER REGION FRI AND FRI NIGHT WITH LIGHT
WINDS AND DIMINISHING SEAS.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY-SUNDAY...SW WINDS MAY GUST UP TO 20 KT SAT/SAT NIGHT THEN
DIMINISH. WITH LONG S-SW FETCH...SEAS FORECAST UP TO 5 FT MAINLY ON
THE SOUTHERN OUTER WATERS.
MONDAY-TUESDAY...CONTINUED SW WINDS IN PLACE...WHICH MAY GUST TO 20
KT AT TIMES. SEAS UP TO 5-7 FT ON THE SOUTHERN OUTER WATERS. MAY SEE
SCT SHOWERS/THUNDERSTORMS MON NIGHT/TUE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR
ANZ230>234-236-251.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ235-
237.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT FRIDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...EVT/JWD
NEAR TERM...JWD
SHORT TERM...JWD
LONG TERM...EVT
AVIATION...EVT/JWD
MARINE...EVT/JWD
AREA FORECAST DISCUSSION
NWS ALBANY NY
149 PM EDT THU JUL 30 2015
.SYNOPSIS...
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME
SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EARLY EVENING
HOURS. BEHIND THIS BOUNDARY...LESS HUMID AIR WILL MOVE INTO THE AREA
FOR TONIGHT INTO FRIDAY...ALTHOUGH TEMPERATURES WILL CONTINUE TO BE
WARM ON FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN
ON SATURDAY...WITH TEMPERATURES SLIGHTLY ABOVE NORMAL LEVELS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 133 PM EDT...BAND OF RAIN SHOWERS AND EMBEDDED THUNDER
EXTENDS FROM LAKE GEORGE DOWN THROUGH SARATOGA COUNTY AND INTO THE
CAPITAL REGION. FURTHER SOUTH...THE BAND IS NOT AS
CONTINUOUS...BUT SOME SHOWERS ARE IMPACTING THE EASTERN CATSKILLS
AND MID HUDSON VALLEY. ALL OF THIS ACTIVITY WILL CONTINUE TO
GRADUALLY SLIDE EASTWARD OVER THE NEXT FEW HOURS. THERE HAVE BEEN
SOME EMBEDDED HEAVIER BURSTS OF RAINFALL...ESP OVER SARATOGA
COUNTY IN THE BALLSTON SPA AND MALTA AREAS...WHERE DUAL POL RADAR
ESTIMATES AROUND UP TO AN INCH AND A HALF OF RAIN HAS FALLEN.
THE MAIN THREAT THIS AFTN LOOKS TO BE LOCALLY HEAVY RAINFALL...AS
BOTH INSTABILITY AND SHEAR PARAMETERS DON/T FAVOR MUCH IN THE WAY
OF SEVERE STORMS. SPC CONTINUES JUST A MARGINAL RISK FOR SEVERE
STORMS THROUGH THE AFTN HOURS. THE LATEST 3KM HRRR SUGGESTS THAT
THE CURRENT ACTIVITY WILL CONTINUE TO SLIDE EASTWARD INTO NEW
ENGLAND BY THE MID TO LATE AFTN HOURS.
AFTER THE MAIN BAND OF SHOWERS PASSES THROUGH...THE MAIN COLD
FRONT...NOW OVER CENTRAL NY...WILL STILL APPROACH AND MOVE
THROUGH FROM W TO E LATER THIS AFTERNOON/EARLY EVENING. IN
ADDITION...OUR REGION WILL BECOME CLOSER TO THE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET MAX TRANSLATING ACROSS THE EASTERN
GREAT LAKES/SE CANADA LATER TODAY. DEPENDING ON HOW MUCH SUNSHINE
AND LOW LEVEL HEATING OCCURS IN THE WAKE OF THE MIDDAY
SHOWERS...WILL DETERMINE IF ADDITIONAL ISOLATED TO SCATTERED
CONVECTION DEVELOPS CLOSER TO OR ALONG THE FRONT LATER THIS
AFTERNOON. THIS POTENTIAL APPEARS GREATEST FOR AREAS MAINLY S AND
E OF ALBANY...ALTHOUGH STILL REMAINS LOW OVERALL.
PWATS ARE FORECAST TO SURGE AHEAD OF THE COLD FRONT TO +2 TO +3
STDEV ACCORDING TO THE GEFS. THUS SHOWERS/STORMS WILL BE CAPABLE
OF PRODUCING TORRENTIAL DOWNPOURS IN A SHORT AMOUNT OF TIME. SOME
MAINLY MINOR URBAN/POOR DRAINAGE FLOODING WILL BE POSSIBLE...AS
WELL AS ISOLATED FLASH FLOODING.
TEMPERATURES WILL CONTINUE TO BE VERY WARM...BUT COOLER THAN
WEDNESDAY DUE TO INCREASING CLOUDS AND CHANCES FOR SHOWERS/STORMS.
HUMIDITY LEVELS WILL BE HIGHER THOUGH...MAKING IT FEEL QUICK
MUGGY. TEMPS WILL LIKELY SPIKE AHEAD OF THE MAIN BAND OF MIDDAY
SHOWERS...IN THE LOWER/MID 80S IN VALLEY AND UPPER 70S TO NEAR 80
ACROSS HIGHER TERRAIN...THEN MAY DROP INTO THE 70S FOR A FEW HOURS
BEFORE RECOVERING BACK INTO THE UPPER 70S/LOWER 80S AGAIN LATER
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT SHOULD PUSH THROUGH WESTERN NEW ENGLAND EARLY THIS
EVENING...WITH SHOWERS AND THUNDERSTORMS ENDING THERE BY SUNSET.
AREAS TO THE WEST WILL BE DRY TO START THE EVENING WITH A WEST
WIND DEVELOPING BEHIND THE COLD FRONT. AS THE FRONT PUSHES WELL
EAST OF OUR REGION BY LATE EVENING...DRYING AND CLEARING WILL
OCCUR. TEMPERATURES WILL BE COOLER AND CLOSER TO NORMAL TONIGHT
WITH MAINLY UPPER 50S TO MID 60S FOR LOWS.
FRIDAY LOOKS TO BE A QUIET AND SEASONABLE DAY ACROSS THE REGION
AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS IN FROM THE OHIO
VALLEY. JUST SOME FAIR WEATHER CU AND CIRRUS CLOUDS AROUND WITH
NOTICEABLY LESS HUMID CONDITIONS WITH DEWPOINTS IN THE 50S AND A
WESTERLY BREEZE. TEMPERATURES WILL STILL BE SLIGHTLY ABOVE NORMAL
IN MANY SPOTS BUT THE BREEZE AND LOWER HUMIDITY WILL MAKE IT FEEL
MUCH MORE COMFORTABLE.
UPPER LEVEL HEIGHTS WILL START TO GRADUALLY FALL FRIDAY
NIGHT...AS A BROAD TROUGH STARTS TO GET CARVED OUT OVER THE GREAT
LAKES. AN APPROACHING SHORT WAVE AND JET STREAK WILL BRING A LOW
CHANCE OF SHOWERS MAINLY FOR AREAS NORTH OF THE CAPITAL DISTRICT.
THIS DISTURBANCE WILL MOVE ACROSS THE REGION ON
SATURDAY...PROMOTING MAINLY SCATTERED SHOWERS AND THUNDERSTORMS.
TIMING STILL IN QUESTION REGARDING MAGNITUDE OF INSTABILITY...BUT
FOR NOW IT APPEARS AT LEAST GENERAL THUNDERSTORMS WILL OCCUR AS
CLOUDS MAY INCREASE FAIRLY QUICKLY SATURDAY MORNING INTO EARLY
AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PERIOD WILL FEATURE A GRADUALLY DEEPENING LONG WAVE
TROF OVER THE EASTERN UNITED STATES...WITH MINOR DISTURBANCES
ROTATING AROUND THE LONG WAVE TROF AND THROUGH THE ALBANY FORECAST
AREA. THIS WILL RESULT IN AN UNSETTLED PERIOD OF WEATHER WITH SLIGHT
CHANCE TO CHANCE POPS FORECAST JUST ABOUT EVERY PERIOD FOR AT LEAST
SOME PART OF THE FORECAST AREA.. THE ONLY PERIOD THAT IS FORECAST
TO BE DRY FOR THE ENTIRE AREA IS TUESDAY NIGHT...AND THE PERIOD WITH
THE HIGHEST POPS FOR THE ENTIRE AREA (30 TO 40 PERCENT) IS MONDAY
NIGHT AND TUESDAY. THE REST OF THE TIME POPS WILL RANGE FROM DRY
OVER THE SOUTHEAST PART OF THE FORECAST AREA...TO LOW CHANCE POPS
OVER THE ADIRONDACKS...WHICH WILL BE CLOSEST TO INDIVIDUAL
DISTURBANCES ROTATING AROUND THE LONG WAVE TROF. IT SHOULD BE NOTED
THAT THE GFS AND ECMWF VARY WITH THE TIMING OF THESE DISTURBANCES...
SO CONFIDENCE IN THE FORECAST FROM DAY TO DAY IS FAIRLY LOW SINCE
THE TIMING OF THESE SYSTEMS WILL LIKELY CHANGE WITH FUTURE MODEL RUNS.
TEMPERATURE WISE THE LONG TERM PERIOD WILL START OUT A LITTLE ABOVE
NORMAL...WITH A GRADUAL COOL DOWN LATER IN THE PERIOD AS THE LONG
WAVE TROF DEEPENS OVER THE REGION. SPECIFICALLY...LOWS SATURDAY NIGHT
WILL BE IN THE MID 50S TO LOWER 60S. HIGHS SUNDAY GENERALLY IN THE
MID 70S TO MID 80S. LOWS SUNDAY NIGHT IN THE MID 50S TO MID 60S.
HIGHS MONDAY IN THE UPPER 70S AND 80S. LOWS MONDAY NIGHT IN THE MID
50S TO MID 60S. HIGHS TUESDAY IN THE MID 70S TO MID 80S. LOWS
TUESDAY NIGHT IN THE 50S AND LOWER 60S. HIGHS WEDNESDAY IN THE 70S
TO MID 80S...WITH SOME UPPER 60S OVER THE ADIRONDACKS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
BROAD AREA OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WAS MAKING
ITS WAY SOUTHEAST ACROSS KGFL AND KALB AT 1730Z. EXPECTING ACTIVITY
TO CLEAR OUT OF THESE TWO AIRPORTS AROUND 18Z...PUT POPCORN SHOWERS
WILL LINGER WITH WHAT LEFTOVER DAYTIME HEATING INTERACTS WITH SLOWLY-
DEPARTING MOISTURE AT THE LOW AND MID LEVELS...CARRYING JUST VCSH
FOR THIS.
AT KPSM...AND PARTICULARLY AT KPOU...THUNDERSTORMS STARTING SHORTLY
AFTER 18Z AS CELLS WITHIN RAIN AREA GAIN A LITTLE STRENGTH...SHOULD
LAST TIL 20Z. COLD FRONT LAGS BEHIND A COUPLE OF HOURS...THEN
THINGS IMPROVE MORE...ESPECIALLY AROUND SUNSET...UNTIL MVFR/IFR FOG
DEVELOPS AT THE AIRPORTS DURING THE LATE OVERNIGHT.
WINDS WILL PICK UP BRIEFLY BEHIND THE FRONT...WITH LIGHT WINDS THEN
ALLOWING FOR THE FOG...WHICH WILL BURN OFF QUICKLY AFTER SUNRISE DUE
TO LACK OF CLOUD COVER AND EARLY MIXING. THROUGH THE COLUMN...SPEED
SHEAR IS JUST ENOUGH AT KGFL AND KALB TO INCLUDE WS FOR THE EVENING/
OVERNIGHT PERIOD.
OUTLOOK...
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
A COLD FRONT APPROACHING FROM WESTERN NEW YORK WILL RESULT IN
SHOWERS AND THUNDERSTORMS ACROSS THE REGION TODAY...AS THE FRONT
PROGRESSES EASTWARD. IT WILL REMAIN WARM AND MUGGY THROUGH MUCH OF
TODAY AHEAD OF THE COLD FRONT. BEHIND THE COLD FRONT...COOLER AND
DRIER AIR WILL FILTER INTO THE REGION TONIGHT INTO FRIDAY.
TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL INTO THE WEEKEND. CHANCES
FOR SHOWERS AND THUNDERSTORMS WILL INCREASE AGAIN ON SATURDAY...AS
AN UPPER LEVEL DISTURBANCE MOVES ACROSS THE REGION.
MINIMUM RELATIVE HUMIDITY VALUES THIS AFTERNOON ARE EXPECTED TO BE
BETWEEN 50 AND 60 PERCENT...INCREASING TO MAXIMUM VALUES OF 90 TO
100 PERCENT TONIGHT. MIN RH VALUES FRIDAY WILL DROP TO AROUND 35 TO
50 PERCENT DURING THE AFTERNOON.
WINDS TODAY WILL BE SOUTH-SOUTHWEST AROUND 5 TO 10 MPH...BECOMING
SOUTHWEST AROUND 5 MPH TONIGHT. WINDS ON FRIDAY WILL BE WESTERLY AT
5 TO 15 MPH.
&&
.HYDROLOGY...
NO MAIN STEM RIVER FLOODING IS FORECAST THROUGH THE NEXT 5 DAYS.
FAIRLY WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A
COLD FRONT CROSS THE AREA. WITH PWAT VALUES POTENTIALLY NEAR TWO
INCHES...THUNDERSTORMS WILL BE CAPABLE OF PRODUCING VERY HEAVY
RAINFALL...WHICH MAY CAUSE LOCALIZED MINOR FLOODING OF URBAN...LOW
LYING AND POOR DRAINAGE AREAS. ISOLATED FLASH FLOODING CANNOT BE
RULED OUT...BUT THE THREAT WILL NOT BE WIDESPREAD.
MAINLY DRY WEATHER WILL RETURN FOR TONIGHT THROUGH FRIDAY NIGHT.
SOME ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
MAINLY DURING THE FIRST HALF OF THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/KL/JPV
SHORT TERM...JPV
LONG TERM...GJM
AVIATION...ELH
FIRE WEATHER...JPV
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
133 PM EDT THU JUL 30 2015
.SYNOPSIS...
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME
SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EARLY EVENING
HOURS. BEHIND THIS BOUNDARY...LESS HUMID AIR WILL MOVE INTO THE AREA
FOR TONIGHT INTO FRIDAY...ALTHOUGH TEMPERATURES WILL CONTINUE TO BE
WARM ON FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN
ON SATURDAY...WITH TEMPERATURES SLIGHTLY ABOVE NORMAL LEVELS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 133 PM EDT...BAND OF RAIN SHOWERS AND EMBEDDED THUNDER
EXTENDS FROM LAKE GEORGE DOWN THROUGH SARATOGA COUNTY AND INTO THE
CAPITAL REGION. FURTHER SOUTH...THE BAND IS NOT AS
CONTINUOUS...BUT SOME SHOWERS ARE IMPACTING THE EASTERN CATSKILLS
AND MID HUDSON VALLEY. ALL OF THIS ACTIVITY WILL CONTINUE TO
GRADUALLY SLIDE EASTWARD OVER THE NEXT FEW HOURS. THERE HAVE BEEN
SOME EMBEDDED HEAVIER BURSTS OF RAINFALL...ESP OVER SARATOGA
COUNTY IN THE BALLSTON SPA AND MALTA AREAS...WHERE DUAL POL RADAR
ESTIMATES AROUND UP TO AN INCH AND A HALF OF RAIN HAS FALLEN.
THE MAIN THREAT THIS AFTN LOOKS TO BE LOCALLY HEAVY RAINFALL...AS
BOTH INSTABILITY AND SHEAR PARAMETERS DON/T FAVOR MUCH IN THE WAY
OF SEVERE STORMS. SPC CONTINUES JUST A MARGINAL RISK FOR SEVERE
STORMS THROUGH THE AFTN HOURS. THE LATEST 3KM HRRR SUGGESTS THAT
THE CURRENT ACTIVITY WILL CONTINUE TO SLIDE EASTWARD INTO NEW
ENGLAND BY THE MID TO LATE AFTN HOURS.
AFTER THE MAIN BAND OF SHOWERS PASSES THROUGH...THE MAIN COLD
FRONT...NOW OVER CENTRAL NY...WILL STILL APPROACH AND MOVE
THROUGH FROM W TO E LATER THIS AFTERNOON/EARLY EVENING. IN
ADDITION...OUR REGION WILL BECOME CLOSER TO THE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET MAX TRANSLATING ACROSS THE EASTERN
GREAT LAKES/SE CANADA LATER TODAY. DEPENDING ON HOW MUCH SUNSHINE
AND LOW LEVEL HEATING OCCURS IN THE WAKE OF THE MIDDAY
SHOWERS...WILL DETERMINE IF ADDITIONAL ISOLATED TO SCATTERED
CONVECTION DEVELOPS CLOSER TO OR ALONG THE FRONT LATER THIS
AFTERNOON. THIS POTENTIAL APPEARS GREATEST FOR AREAS MAINLY S AND
E OF ALBANY...ALTHOUGH STILL REMAINS LOW OVERALL.
PWATS ARE FORECAST TO SURGE AHEAD OF THE COLD FRONT TO +2 TO +3
STDEV ACCORDING TO THE GEFS. THUS SHOWERS/STORMS WILL BE CAPABLE
OF PRODUCING TORRENTIAL DOWNPOURS IN A SHORT AMOUNT OF TIME. SOME
MAINLY MINOR URBAN/POOR DRAINAGE FLOODING WILL BE POSSIBLE...AS
WELL AS ISOLATED FLASH FLOODING.
TEMPERATURES WILL CONTINUE TO BE VERY WARM...BUT COOLER THAN
WEDNESDAY DUE TO INCREASING CLOUDS AND CHANCES FOR SHOWERS/STORMS.
HUMIDITY LEVELS WILL BE HIGHER THOUGH...MAKING IT FEEL QUICK
MUGGY. TEMPS WILL LIKELY SPIKE AHEAD OF THE MAIN BAND OF MIDDAY
SHOWERS...IN THE LOWER/MID 80S IN VALLEY AND UPPER 70S TO NEAR 80
ACROSS HIGHER TERRAIN...THEN MAY DROP INTO THE 70S FOR A FEW HOURS
BEFORE RECOVERING BACK INTO THE UPPER 70S/LOWER 80S AGAIN LATER
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT SHOULD PUSH THROUGH WESTERN NEW ENGLAND EARLY THIS
EVENING...WITH SHOWERS AND THUNDERSTORMS ENDING THERE BY SUNSET.
AREAS TO THE WEST WILL BE DRY TO START THE EVENING WITH A WEST
WIND DEVELOPING BEHIND THE COLD FRONT. AS THE FRONT PUSHES WELL
EAST OF OUR REGION BY LATE EVENING...DRYING AND CLEARING WILL
OCCUR. TEMPERATURES WILL BE COOLER AND CLOSER TO NORMAL TONIGHT
WITH MAINLY UPPER 50S TO MID 60S FOR LOWS.
FRIDAY LOOKS TO BE A QUIET AND SEASONABLE DAY ACROSS THE REGION
AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS IN FROM THE OHIO
VALLEY. JUST SOME FAIR WEATHER CU AND CIRRUS CLOUDS AROUND WITH
NOTICEABLY LESS HUMID CONDITIONS WITH DEWPOINTS IN THE 50S AND A
WESTERLY BREEZE. TEMPERATURES WILL STILL BE SLIGHTLY ABOVE NORMAL
IN MANY SPOTS BUT THE BREEZE AND LOWER HUMIDITY WILL MAKE IT FEEL
MUCH MORE COMFORTABLE.
UPPER LEVEL HEIGHTS WILL START TO GRADUALLY FALL FRIDAY
NIGHT...AS A BROAD TROUGH STARTS TO GET CARVED OUT OVER THE GREAT
LAKES. AN APPROACHING SHORT WAVE AND JET STREAK WILL BRING A LOW
CHANCE OF SHOWERS MAINLY FOR AREAS NORTH OF THE CAPITAL DISTRICT.
THIS DISTURBANCE WILL MOVE ACROSS THE REGION ON
SATURDAY...PROMOTING MAINLY SCATTERED SHOWERS AND THUNDERSTORMS.
TIMING STILL IN QUESTION REGARDING MAGNITUDE OF INSTABILITY...BUT
FOR NOW IT APPEARS AT LEAST GENERAL THUNDERSTORMS WILL OCCUR AS
CLOUDS MAY INCREASE FAIRLY QUICKLY SATURDAY MORNING INTO EARLY
AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PERIOD WILL FEATURE A GRADUALLY DEEPENING LONG WAVE
TROF OVER THE EASTERN UNITED STATES...WITH MINOR DISTURBANCES
ROTATING AROUND THE LONG WAVE TROF AND THROUGH THE ALBANY FORECAST
AREA. THIS WILL RESULT IN AN UNSETTLED PERIOD OF WEATHER WITH SLIGHT
CHANCE TO CHANCE POPS FORECAST JUST ABOUT EVERY PERIOD FOR AT LEAST
SOME PART OF THE FORECAST AREA.. THE ONLY PERIOD THAT IS FORECAST
TO BE DRY FOR THE ENTIRE AREA IS TUESDAY NIGHT...AND THE PERIOD WITH
THE HIGHEST POPS FOR THE ENTIRE AREA (30 TO 40 PERCENT) IS MONDAY
NIGHT AND TUESDAY. THE REST OF THE TIME POPS WILL RANGE FROM DRY
OVER THE SOUTHEAST PART OF THE FORECAST AREA...TO LOW CHANCE POPS
OVER THE ADIRONDACKS...WHICH WILL BE CLOSEST TO INDIVIDUAL
DISTURBANCES ROTATING AROUND THE LONG WAVE TROF. IT SHOULD BE NOTED
THAT THE GFS AND ECMWF VARY WITH THE TIMING OF THESE DISTURBANCES...
SO CONFIDENCE IN THE FORECAST FROM DAY TO DAY IS FAIRLY LOW SINCE
THE TIMING OF THESE SYSTEMS WILL LIKELY CHANGE WITH FUTURE MODEL RUNS.
TEMPERATURE WISE THE LONG TERM PERIOD WILL START OUT A LITTLE ABOVE
NORMAL...WITH A GRADUAL COOL DOWN LATER IN THE PERIOD AS THE LONG
WAVE TROF DEEPENS OVER THE REGION. SPECIFICALLY...LOWS SATURDAY NIGHT
WILL BE IN THE MID 50S TO LOWER 60S. HIGHS SUNDAY GENERALLY IN THE
MID 70S TO MID 80S. LOWS SUNDAY NIGHT IN THE MID 50S TO MID 60S.
HIGHS MONDAY IN THE UPPER 70S AND 80S. LOWS MONDAY NIGHT IN THE MID
50S TO MID 60S. HIGHS TUESDAY IN THE MID 70S TO MID 80S. LOWS
TUESDAY NIGHT IN THE 50S AND LOWER 60S. HIGHS WEDNESDAY IN THE 70S
TO MID 80S...WITH SOME UPPER 60S OVER THE ADIRONDACKS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT WILL MOVE ACROSS THE REGION DURING THE AFTERNOON...
ACCOMPANIED BY SOME SHOWERS AND THUNDERSTORMS.
EXCEPT FOR MVFR CIGS AT KPOU...EXPECT MAINLY VFR CONDITIONS AT
THE KALB/KGFL/KPOU/KPSF TAF SITES UNTIL THE COLD FRONT APPROACHES.
THE COLD FRONT WILL MOVE ACROSS THE REGION THIS AFTERNOON...AND
HAVE GENERALLY FORECAST A 3-4 HOUR PERIOD OF SHOWERS AT ALL THE
TAF SITES. WILL ALSO INCLUDE MENTION OF VCTS...AS SOME EMBEDDED
THUNDERSTORMS WILL BE POSSIBLE. AT KGFL THE WINDOW FOR
SHOWERS/POSSIBLE TSTMS IS FROM 16Z-18Z...KALB 17Z- 19Z...KPSF AND
KPOU 19Z- 21Z.
AFTER THE COLD FRONT MOVES THROUGH AND ANY CONVECTIVE ACTIVITY
ENDS...EXPECT VFR CONDITIONS TO RETURN TO ALL THE TAF SITES...BUT
MVFR/IFR CONDITIONS POSSIBLE LATE TONIGHT DUE TO THE POSSIBILITY
OF FOG FORMATION.
SURFACE WINDS WILL BE SOUTH TO SOUTHWEST 5 TO 10 KTS EARLY TODAY.
AFTER THE FRONT MOVES THROUGH...WINDS WILL BECOME WEST TO
SOUTHWEST. AFTER SUNSET...WINDS WILL BECOME LIGHT AND VARIABLE.
WINDS WILL BE MUCH STRONGER...AND VARIABLE IN DIRECTION IN AND
NEAR ANY THUNDERSTORMS.
OUTLOOK...
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
A COLD FRONT APPROACHING FROM WESTERN NEW YORK WILL RESULT IN
SHOWERS AND THUNDERSTORMS ACROSS THE REGION TODAY...AS THE FRONT
PROGRESSES EASTWARD. IT WILL REMAIN WARM AND MUGGY THROUGH MUCH OF
TODAY AHEAD OF THE COLD FRONT. BEHIND THE COLD FRONT...COOLER AND
DRIER AIR WILL FILTER INTO THE REGION TONIGHT INTO FRIDAY.
TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL INTO THE WEEKEND. CHANCES
FOR SHOWERS AND THUNDERSTORMS WILL INCREASE AGAIN ON SATURDAY...AS
AN UPPER LEVEL DISTURBANCE MOVES ACROSS THE REGION.
MINIMUM RELATIVE HUMIDITY VALUES THIS AFTERNOON ARE EXPECTED TO BE
BETWEEN 50 AND 60 PERCENT...INCREASING TO MAXIMUM VALUES OF 90 TO
100 PERCENT TONIGHT. MIN RH VALUES FRIDAY WILL DROP TO AROUND 35 TO
50 PERCENT DURING THE AFTERNOON.
WINDS TODAY WILL BE SOUTH-SOUTHWEST AROUND 5 TO 10 MPH...BECOMING
SOUTHWEST AROUND 5 MPH TONIGHT. WINDS ON FRIDAY WILL BE WESTERLY AT
5 TO 15 MPH.
&&
.HYDROLOGY...
NO MAIN STEM RIVER FLOODING IS FORECAST THROUGH THE NEXT 5 DAYS.
FAIRLY WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A
COLD FRONT CROSS THE AREA. WITH PWAT VALUES POTENTIALLY NEAR TWO
INCHES...THUNDERSTORMS WILL BE CAPABLE OF PRODUCING VERY HEAVY
RAINFALL...WHICH MAY CAUSE LOCALIZED MINOR FLOODING OF URBAN...LOW
LYING AND POOR DRAINAGE AREAS. ISOLATED FLASH FLOODING CANNOT BE
RULED OUT...BUT THE THREAT WILL NOT BE WIDESPREAD.
MAINLY DRY WEATHER WILL RETURN FOR TONIGHT THROUGH FRIDAY NIGHT.
SOME ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
MAINLY DURING THE FIRST HALF OF THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/KL/JPV
SHORT TERM...JPV
LONG TERM...GJM
AVIATION...KL/GJM
FIRE WEATHER...JPV
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS DES MOINES IA
359 PM CDT THU JUL 30 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 357 PM CDT THU JUL 30 2015
SURFACE HIGH WILL REMAIN IN PLACE OVER FAR SOUTHERN IOWA TONIGHT
WHILE ALOFT WE WILL REMAIN IN NORTHWEST FLOW. THE NAM IS SUGGESTING
A SUBTLE SHORTWAVE CROSSING SOUTHWEST IOWA OVERNIGHT AS A WEAK COLD
FRONT SINKS INTO THE NORTHWEST QUARTER OR SO OF THE STATE. THERE IS
SOME POSSIBILITY THAT A SPRINKLE OR TWO COULD BE ASSOCIATED WITH
EITHER OF THESE FEATURES BUT INSTABILITY IS RATHER MINIMAL AND
FORCING IS TIED MORE TO THE FRONTAL BOUNDARY THAN THE SUBTLE WAVE
ACROSS THE SOUTH...WHERE THE BETTER INSTABILITY LIES. CONFIDENCE AS
TO WHERE ANY PRECIP MAY OCCUR IS VERY LOW AND AS SUCH I DO NOT HAVE
A MENTION OF POPS IN THE FORECAST. HI-RES CONVECTION ALLOWING
MODELS ARE IN POOR AGREEMENT AS WELL AS THE HRRR CURRENTLY IS
FORECASTING SHOWERS ACROSS THE NORTHERN HALF OF IOWA WHERE THERE ARE
BARELY A FEW CLOUDS. THE NAM 12 HAS SPITS OF PRECIP OVER BOTH THE
SOUTH AND NORTHWEST WHILE THE OTHER MODELS DO THIS OVER THE SOUTH.
COVERAGE WOULD BE SPARSE AND POPS MAY NEED TO BE ADJUSTED IN LATER
SHIFTS IF SOMETHING IS ABLE TO DEVELOP. AS FOR TEMPS...NORTHWEST
IOWA SHOULD BE THE COOLEST AS THE FRONT WILL BE THROUGH THEM BUT IT
IS DOUBTFUL THAT IT WILL MAKE IT TOO FAR INTO OUR FORECAST AREA BY
12Z. AS A RESULT I HAVE KEPT LOWER 60S NORTH TO MID 60S SOUTH FOR
TONIGHT`S LOWS.
.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 357 PM CDT THU JUL 30 2015
GENERAL PREMISE OF LONG TERM LOOKING SIMILAR TO YESTERDAY/S OUTPUT.
DIFFERENCE IS THAT TODAY/S RUNS ARE A LITTLE MORE AMPLIFIED AND
CONFIDENCE INCREASED IN MULTIPLE ROUND OF PRECIP OF THE NEXT SEVEN
DAYS. FROM 12Z UNTIL 18Z FRIDAY...A WEAK BOUNDARY WILL BE PASSING
THROUGH OUR CWA FROM NW TO SE. PWATS WITH THIS BOUNDARY BARELY GO
ABOVE 1 INCH AND MOISTURE CONV AT THE SFC IS MINIMAL. TIME OF DAY
ALSO TYPICALLY NOT FAVORABLE FOR CONVECTION. THEREFORE...AM
KEEPING CWA DRY WITH THIS BOUNDARY PASSAGE. EXPECT ANOTHER MAINLY
CLOUD- FREE DAY WITH 850MB TEMPS IN THE 17C TO 20C RANGE TO MIX
DOWN AND YIELD MID TO UPPER 80S.
FRIDAY EVENING INTO SATURDAY MORNING...THE AFOREMENTIONED BOUNDARY
LOOKS TO LINGER IN NORTHERN MISSOURI TO NORTHEASTERN NEBRASKA AND
WILL SERVE AS THE FOCUSING MECHANISM FOR EVENING
CONVECTION...ESPECIALLY IN NORTHEASTERN NEBRASKA. CORFIDI VECTORS
SUGGEST STORM MOVEMENT WILL BE TO THE SE...WITH ANY RIGHT-MOVERS
MOVING MORE SOUTHERLY. WITH ENOUGH INSTABILITY PRESENT IN SOUTHERN
IOWA AHEAD OF THESE STORMS...IT SEEMS PLAUSIBLE ANY OUTFLOW
BOUNDARIES WILL PROPAGATE IN A NE/E DIRECTION INTO SOUTHERN
IOWA...POSSIBLY CLIPPING OUR SW COUNTIES. THEREFORE HAVE SOME
SLIGHT POPS GOING IN OUR SOUTH WHICH CAN OBVIOUSLY BE TWEAKED IN
NEXT UPDATES.
SATURDAY LOOKS TO BE DRY...BUT THE NEXT PRECIP CHANCES FOR ARRIVE
LATE EVENING INTO THE OVERNIGHT PERIOD FOR SUNDAY MORNING. MODELS
NOW VERY CONSISTENT IN PRODUCING A SIZABLE MCS OVER SE SOUTH DAKOTA
AND PROPAGATING THIS MCS SOUTHEASTWARD THROUGH THE CENTRAL TO
WESTERN PORTIONS OF OUR CWA. GFS SEEMING TO BE A FAST OUTLIER...SO
LEANED AWAY FROM IT FOR TIMING PURPOSES. AM STARTING TO SEE HEAVY
RAINFALL SIGNATURE AS SHORT TERM MODELS PLACING A SLUG OF 2 TO 2.25
INCH PWATS WITH THIS MCS...MIXING RATIOS OVER 8 J/KG...AND 0 TO 6 MU
CAPE OVER 1500 J/KG. IN FACT THE 18Z NAM HAD PWATS OVER 2.5
INCHES...SO RECENT MODEL TRENDS CERTAINLY POINTING UPWARDS.
BEYOND SUNDAY...YESTERDAY/S LONG TERM MODELS HINTED AT A
BAROCLINIC ZONE TRYING TO ESTABLISH ITSELF OVER OUR SOUTHERN CWA
THROUGH MID WEEK. REGION TO REMAIN IN WESTERLY TO NORTHWESTERLY
FLOW ALOFT...SUGGESTING AN OVERALL PATTERN OF SHORTWAVE
PROPAGATION THROUGH IOWA. TODAY/S MODEL RUNS YIELD A SIMILAR
SETUP TO YESTERDAY/S...WITH THE MAIN DIFFERENCE BEING HIGHER PWATS
IN THE 1.5 INCH RANGE OR SO OVER MUCH OF OUR CWA. THUS...HAVE
INCREASED POPS FURTHER NORTH FROM YESTERDAY AND UPPED CONFIDENCE
SLIGHTLY. INTERESTING THAT THE GFS...WHICH OFTEN HAS A DRY
BIAS...IS PRODUCING SO MUCH MOISTURE IN IOWA. IF UPWARD TREND
CONTINUES...NEXT WEEK COULD BE WET. WITH EXPECTED CLOUD
COVER...BEGUN TO TRIM DIURNAL RANGE...SLIGHTLY LOWERING MAX TEMPS
AND INCREASING MIN TEMPS.
&&
.AVIATION...30/18Z
ISSUED AT 1210 PM CDT THU JUL 30 2015
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. WARM ADVECTION WILL
BE RESPONSIBLE FOR SOME SCT MID/HIGH LEVEL CLOUDS. AFT 03Z A WEAK
COLD FRONT WILL SINK SOUTH ACROSS THE TAF LOCATIONS. THIS WILL
BRING A SCT-BKN DECK BTWN 080-100KFT WHICH IS EXPECTED TO DIMINISH
LATE IN THE FCST PD. SFC WND WILL BECOME NW AFT 03Z WITH THE FROPA
AND MAY INCREASE AFT 13Z TO 10-15KTS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...KOTENBERG
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
436 PM MDT THU JUL 30 2015
.UPDATE...
ISSUED AT 430 PM MDT THU JUL 30 2015
ISSUED A QUICK UPDATE TO ADJUST COVERAGE AND THUNDERSTORM TIMING
MOVING INTO THE EASTERN COLORADO COUNTIES. THE WRF MODELS SEEM TO
BE HAVING THE BEST HANDLE ON THE CURRENT CONVECTIVE MODE...HOWEVER
PRECIPITATION IN THE MODELS ARE 3-6 HOURS LATE IN DEVELOPMENT.
STORMS MAY DISSIPATE EARLIER THAN ANTICIPATED DUE TO THE EARLIER
DEVELOPMENT...BUT WILL LEAVE IN PRECIPITATION CHANCES AFTER
MIDNIGHT MDT FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 200 PM MDT THU JUL 30 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE
ACROSS THE SOUTHERN PLAINS EXTENDING ACROSS THE CENTRAL ROCKIES AND
ACROSS THE GREAT BASIN. NW FLOW IS IN PLACE ACROSS THE NORTHERN
PLAINS AND GREAT LAKES REGIONS. A WEAK RIPPLE IN THE HEIGHT FIELD IS
DEPICTED OVER NW KANSAS WITH A STRONGER PV HEIGHT ANOMALY OVER NEW
MEXICO AND STRONGER SIGNAL IN WV IMAGERY. AT THE SURFACE LOW
PRESSURE HAS DEVELOPED ACROSS EASTERN COLORADO WITH A STATIONARY
FRONT EXTENDING FROM THE SW TO NE TOWARDS THE NEBRASKA PANHANDLE.
HIGH PRESSURE IS IN PLACE ACROSS THE CENTRAL PLAINS AND CENTRAL
MISSISSIPPI RIVER VALLEY.
THIS AFTERNOON-TONIGHT...CAPE VALUES IN THE 1500-2500 J/KG RANGE ARE
CURRENTLY IN PLACE WITH HIGHER TD VALUES (UPPER 50S TO MID 60S).
RAP/HRRR INDICATE CAP ALREADY WEAKENED...AND THUNDERSTORM ACTIVITY
MAY BEGIN TO DEVELOP ALONG WEAK CONVERGENCE ZONE NEAR SURFACE
TROUGH/STATIONARY FRONT IN EASTERN COLORADO. GUIDANCE GENERALLY
SHOWS BETTER PRECIP SIGNAL IN THIS AREA. VERY WEAK LIFT IS IN PLACE
AND AT THIS POINT COVERAGE LOOKS TO BE ISOLATED TO WIDELY SCATTERED
THROUGH TONIGHT. THERE WILL BE SOME WAA THROUGH THE NIGHT WHICH
COULD SUPPORT CONTINUED DEVELOPMENT...HOWEVER WITH BEST FORCING
OUTSIDE OUR CWA...NOT A LOT OF CONFIDENCE. I LIMITED POPS TO 15-24
RANGE (SLIGHT CHANCE). WITH WEAK SHEER PROFILES IN PLACE...LIMITED
FORCING...AND MID LEVEL LAPSE RATES MAINLY LESS THAN 7 C/KM
THUNDERSTORM ACTIVITY IS NOT EXPECTED TO BECOME ORGANIZED.
FRIDAY...SURFACE TROUGH SHIFTS EAST TO BE CENTERED ROUGHLY OVER OUR
CWA AND MAY ACT AS A FOCUS/INITIATION POINT FOR AFTERNOON
THUNDERSTORM ACTIVITY. BEST UPPER LEVEL SUPPORT IS IN THE MORNING
OUTSIDE OUR CWA...WITH POSSIBLY LESS UPPER LEVEL SUPPORT FRIDAY
AFTERNOON THAN TODAY. THERE SHOULD STILL BE ENOUGH
INSTABILITY/MOISTURE IN PLACE TO SUPPORT SOME THUNDERSTORM ACTIVITY
ALONG TROUGH AXIS...HOWEVER COVERAGE STILL APPEARS TO BE ISOLATED IN
NATURE. EFFECTIVE SHEER PROFILES AROUND 30KT AND CAPE VALUES 1500-
3000 J/KG COULD SUPPORT A FEW STRONGER STORMS HOWEVER LIKE TODAY
SEVERE THREAT APPEARS TO BE LOW. HIGH TEMPERATURES WILL BE SLIGHTLY
WARMER AND STILL SEASONAL WITH VALUES RANGING FROM THE UPPER 80S TO
LOWER 90S. A FEW MID 90 TEMPERATURES WILL BE POSSIBLE AT KMCK/KHLC.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 150 PM MDT THU JUL 30 2015
ABOVE NORMAL TEMPERATURES ARE ON TAP FOR THE ENTIRE TRI STATE
REGION...AS MAIN WEATHER FOCUS FOR THE EXTENDED PERIOD WILL CONCERN
AMPLIFIED H5/H7 RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...
SHIFTING EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY/THURSDAY.
EXPECTING BROAD WNW DOWNSLOPE FLOW AT 700/500 MB WITH RIDGE TO OUR
WEST...WITH RIDGE AXIS OVER THE PLAINS BY MIDWEEK NEXT WEEK. 850 MB
TEMPS DO RANGE FROM +28C UP TO +33C DURING THIS TIME...WITH WARMEST
SET TO OCCUR WED/THURS...COINCIDING WITH RIDGE AXIS SETTING UP OVER
THE AREA. WITH THESE CONDITIONS...DAYTIME HIGH TEMPERATURES WILL
RANGE IN THE LOWER TO MID 90S...AND OVERNIGHT LOWS IN THE LOW TO MID
60S.
THE AREA WILL ALSO SEE THE CHANCES FOR SHOWERS AND THUNDERSTORMS
DESPITE THE INCREASE TEMPS. SEVERAL SHORTWAVES MOVING DOWN ALONG THE
EAST SIDE OF THE MID-LEVEL RIDGE FRIDAY/FRIDAY NIGHT...NEXT MONDAY
INTO TUESDAY...AND AGAIN LATE WEDNESDAY INTO THURSDAY WHEN SURFACE
FRONT IS FOLLOWED BY TRAILING SHORTWAVE. CURRENT GFS A BIT MORE IN-
LINE WITH LATEST ECMWF...MAKING CONFIDENCE A BIT STRONGER IN KEEPING
CHANCE POPS FOR LATTER PORTION OF THE FORECAST. THE PUSH OF THE
UPPER RIDGE EASTWARD INTO THE PLAINS DOES PUT A BIT MORE EMPHASIS
FOR HIGHER POP CHANCES OVER EASTERN ZONES ON WEDNESDAY INTO
THURSDAY. AS WITH EXPECTED RAINFALL POTENTIAL...THE CLOUD COVER WITH
THESE EVENTS COULD IMPACT DAYTIME HIGHS/OVERNIGHT LOWS...ESPECIALLY
IN EASTERN ZONES AS WEEK PROGRESSES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1124 AM MDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK TERMINALS. PRIMARY AVIATION CONCERN WILL BE POTENTIAL FOR
THUNDERSTORMS AT BOTH TERMINALS THIS AFTERNOON AND EVENING. AT
THIS TIME IT APPEARS COVERAGE WILL BE ISOLATED WITH LIMITED
INSTABILITY AND FORCING. CONFIDENCE IS TOO LOW TO INCLUDE MENTION
AT EITHER TERMINAL...SO WILL NEED TO MONITOR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...MK
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
200 PM MDT THU JUL 30 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 200 PM MDT THU JUL 30 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE
ACROSS THE SOUTHERN PLAINS EXTENDING ACROSS THE CENTRAL ROCKIES AND
ACROSS THE GREAT BASIN. NW FLOW IS IN PLACE ACROSS THE NORTHERN
PLAINS AND GREAT LAKES REGIONS. A WEAK RIPPLE IN THE HEIGHT FIELD IS
DEPICTED OVER NW KANSAS WITH A STRONGER PV HEIGHT ANOMALY OVER NEW
MEXICO AND STRONGER SIGNAL IN WV IMAGERY. AT THE SURFACE LOW
PRESSURE HAS DEVELOPED ACROSS EASTERN COLORADO WITH A STATIONARY
FRONT EXTENDING FROM THE SW TO NE TOWARDS THE NEBRASKA PANHANDLE.
HIGH PRESSURE IS IN PLACE ACROSS THE CENTRAL PLAINS AND CENTRAL
MISSISSIPPI RIVER VALLEY.
THIS AFTERNOON-TONIGHT...CAPE VALUES IN THE 1500-2500 J/KG RANGE ARE
CURRENTLY IN PLACE WITH HIGHER TD VALUES (UPPER 50S TO MID 60S).
RAP/HRRR INDICATE CAP ALREADY WEAKENED...AND THUNDERSTORM ACTIVITY
MAY BEGIN TO DEVELOP ALONG WEAK CONVERGENCE ZONE NEAR SURFACE
TROUGH/STATIONARY FRONT IN EASTERN COLORADO. GUIDANCE GENERALLY
SHOWS BETTER PRECIP SIGNAL IN THIS AREA. VERY WEAK LIFT IS IN PLACE
AND AT THIS POINT COVERAGE LOOKS TO BE ISOLATED TO WIDELY SCATTERED
THROUGH TONIGHT. THERE WILL BE SOME WAA THROUGH THE NIGHT WHICH
COULD SUPPORT CONTINUED DEVELOPMENT...HOWEVER WITH BEST FORCING
OUTSIDE OUR CWA...NOT A LOT OF CONFIDENCE. I LIMITED POPS TO 15-24
RANGE (SLIGHT CHANCE). WITH WEAK SHEER PROFILES IN PLACE...LIMITED
FORCING...AND MID LEVEL LAPSE RATES MAINLY LESS THAN 7 C/KM
THUNDERSTORM ACTIVITY IS NOT EXPECTED TO BECOME ORGANIZED.
FRIDAY...SURFACE TROUGH SHIFTS EAST TO BE CENTERED ROUGHLY OVER OUR
CWA AND MAY ACT AS A FOCUS/INITIATION POINT FOR AFTERNOON
THUNDERSTORM ACTIVITY. BEST UPPER LEVEL SUPPORT IS IN THE MORNING
OUTSIDE OUR CWA...WITH POSSIBLY LESS UPPER LEVEL SUPPORT FRIDAY
AFTERNOON THAN TODAY. THERE SHOULD STILL BE ENOUGH
INSTABILITY/MOISTURE IN PLACE TO SUPPORT SOME THUNDERSTORM ACTIVITY
ALONG TROUGH AXIS...HOWEVER COVERAGE STILL APPEARS TO BE ISOLATED IN
NATURE. EFFECTIVE SHEER PROFILES AROUND 30KT AND CAPE VALUES 1500-
3000 J/KG COULD SUPPORT A FEW STRONGER STORMS HOWEVER LIKE TODAY
SEVERE THREAT APPEARS TO BE LOW. HIGH TEMPERATURES WILL BE SLIGHTLY
WARMER AND STILL SEASONAL WITH VALUES RANGING FROM THE UPPER 80S TO
LOWER 90S. A FEW MID 90 TEMPERATURES WILL BE POSSIBLE AT KMCK/KHLC.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 150 PM MDT THU JUL 30 2015
ABOVE NORMAL TEMPERATURES ARE ON TAP FOR THE ENTIRE TRI STATE
REGION...AS MAIN WEATHER FOCUS FOR THE EXTENDED PERIOD WILL CONCERN
AMPLIFIED H5/H7 RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...
SHIFTING EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY/THURSDAY.
EXPECTING BROAD WNW DOWNSLOPE FLOW AT 700/500 MB WITH RIDGE TO OUR
WEST...WITH RIDGE AXIS OVER THE PLAINS BY MIDWEEK NEXT WEEK. 850 MB
TEMPS DO RANGE FROM +28C UP TO +33C DURING THIS TIME...WITH WARMEST
SET TO OCCUR WED/THURS...COINCIDING WITH RIDGE AXIS SETTING UP OVER
THE AREA. WITH THESE CONDITIONS...DAYTIME HIGH TEMPERATURES WILL
RANGE IN THE LOWER TO MID 90S...AND OVERNIGHT LOWS IN THE LOW TO MID
60S.
THE AREA WILL ALSO SEE THE CHANCES FOR SHOWERS AND THUNDERSTORMS
DESPITE THE INCREASE TEMPS. SEVERAL SHORTWAVES MOVING DOWN ALONG THE
EAST SIDE OF THE MID-LEVEL RIDGE FRIDAY/FRIDAY NIGHT...NEXT MONDAY
INTO TUESDAY...AND AGAIN LATE WEDNESDAY INTO THURSDAY WHEN SURFACE
FRONT IS FOLLOWED BY TRAILING SHORTWAVE. CURRENT GFS A BIT MORE IN-
LINE WITH LATEST ECMWF...MAKING CONFIDENCE A BIT STRONGER IN KEEPING
CHANCE POPS FOR LATTER PORTION OF THE FORECAST. THE PUSH OF THE
UPPER RIDGE EASTWARD INTO THE PLAINS DOES PUT A BIT MORE EMPHASIS
FOR HIGHER POP CHANCES OVER EASTERN ZONES ON WEDNESDAY INTO
THURSDAY. AS WITH EXPECTED RAINFALL POTENTIAL...THE CLOUD COVER WITH
THESE EVENTS COULD IMPACT DAYTIME HIGHS/OVERNIGHT LOWS...ESPECIALLY
IN EASTERN ZONES AS WEEK PROGRESSES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1124 AM MDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK TERMINALS. PRIMARY AVIATION CONCERN WILL BE POTENTIAL FOR
THUNDERSTORMS AT BOTH TERMINALS THIS AFTERNOON AND EVENING. AT
THIS TIME IT APPEARS COVERAGE WILL BE ISOLATED WITH LIMITED
INSTABILITY AND FORCING. CONFIDENCE IS TOO LOW TO INCLUDE MENTION
AT EITHER TERMINAL...SO WILL NEED TO MONITOR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
143 PM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 526 AM EDT THU JUL 30 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS A PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA WHILE A BROAD RIDGE
REMAINS ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE
FEATURES A NW FLOW WILL DOMINATE THE GREAT LAKES REGION ALLOWING A
SERIES OF MAINLY WEAK AND MOISTURE STARVED SHORTWAVES TO PASS THRU
AREA RESULTING IN PERIODIC LIGHT PCPN. TYPICALLY...THESE WEAK
SHORTWAVES ARE POORLY RESOLVED BY MODELS WHICH WILL MAKE FOR A
TRICKY FCST IN THE LONG TERM. IT LOOKS LIKE TEMPERATURES WILL BE
NEAR NORMAL THROUGH THE WEEKEND AND THEN PERHAPS TREND BELOW NORMAL
FOR THE EARLY PART OF NEXT WEEK BEHIND AS A MORE AMPLIFIED SHORTWAVE
AND ASSOC COLD FRONT PASS THROUGH THE UPPER GREAT LAKES REGION.
FRI INTO SAT...MOST OF MODELS HINT AT A FEW WEAK SHORTWAVES MOVING
THROUGH THE AREA...ONE FRI MORNING AND ANOTHER FRI NIGHT. WITH
SEVERAL OF THE MODELS SHOWING 100-300 J/KG OF MLCAPE AHEAD OF THESE
WAVES WILL PROBABLY NEED TO MAINTAIN AT LEAST SLIGHT CHC POPS FOR
ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW EXPECT ANY PCPN
FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
SATURDAY LOOKS TO BE TRENDING DRIER AS MOST OF THE MODELS INDICATE
SHORTWAVE ENERGY PASSING EAST OF THE AREA SAT MORNING...ALTHOUGH A
POCKET OF HIGHER INSTABILITY NOTED ALONG LAKE MI COUNTIES MAY STILL
WARRANT SLIGHT CHC POPS THERE.
TEMPERATURES FRI THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS COMING INTO A LITTLE BETTER AGREEMENT ON TIMING OF STRONGER
SHORTWAVE COMING DOWN FM SCNTRL CANADA AND ASSOC COLD FROPA FOR SUN
NIGHT/MON TIME FRAME. WILL CONTINUE LOW CHC POPS 30-40 PCT AT THIS
TIME...AND GIVEN STRENGTH OF SHORTWAVE THIS MAY BE BEST OPPORTUNITY
TO SEE WIDEPSREAD ALBEIT LIGHT PCPN. MODELS ADVERTISE BELOW NORMAL
TEMPS FOR MON-WED IN THE WAKE OF THE FROPA AS LATEST 00Z ECMWF SHOWS
8H TEMPS DROPPING TO 4-6C BY MON EVENING AND THEN PERSISTING IN THAT
RANGE INTO WED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 142 PM EDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WINDS WILL DECREASE
THIS EVENING AND TONIGHT. THERE MAY BE ISOLATED SHRA NEAR KIWD LATE
THIS AFTERNOON...BUT POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE
IS LOW ENOUGH TO ONLY INCLUDE VCSH IN TAF.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HUDSON BAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE WEST-
NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...TITUS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1233 PM EDT THU JUL 30 2015
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 330 AM EDT THU JUL 30 2015
PLEASANT SUMMER WEATHER IS IN STORE OVER THE NEXT FEW DAYS WITH
COMFORTABLE TEMPERATURES AND HUMIDITY LEVELS ALONG WITH PLENTY OF
SUNSHINE AND FRESH WESTERLY BREEZES.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SFC DEW POINTS IN THE 50S HAVE PUSHED INTO SW LWR MI SETTING THE
STAGE FOR SOME STELLAR SUMMER WEATHER THROUGH SATURDAY. HOWEVER
WINDS WILL BE GUSTY IN THE AFTERNOONS WHEN DEEP MIXING AND DRY AIR
MASS/STEEP LAPSE RATES LEADS TO EFFICIENT MOMENTUM TRANSFER OF
STRONGER 25-30 KTS WINDS AT 3000-5000 FT.
OCCASIONAL FAST MOVING SHORTWAVES DIVING SOUTHEAST THROUGH THE
NORTHERN GRTLKS REGION AND ASSOCIATED WEAK SFC TROUGHS MAY SUPPORT A
SLIGHT CHANCE OF A SHOWER OR TSTM BOTH FRIDAY OR SATURDAY. HOWEVER
THE BIG LIMITING FACTOR WILL BE THE MODERATE LOW LEVEL WESTERLY
FLOW OFF LK MI SENDING STABLE AIR WELL INLAND AND PREVENTING ANY
DECENT LOW LEVEL CONVERGENCE. TYPICALLY THIS KEEPS THE BULK OF SW
LWR MI DRY WITH A LOW POTENTIAL USUALLY LIMITED TO JUST THE
NORTHEAST CORNER OF THE CWFA AROUND CLARE.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SEASONABLE TEMPERATURES ARE ANTICIPATED SATURDAY NIGHT THROUGH
SUNDAY. THERE IS A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS LATE
SATURDAY NIGHT AND SUNDAY WITH A POTENTIALLY BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE SUNDAY NIGHT OR MONDAY WITH A
STRONGER COLD FRONT AND AS THE LONGWAVE UPPER LEVEL TROUGH
BECOMES MORE AMPLIFIED OVER THE GREAT LAKES REGION.
THE EVOLUTION OF THE UPPER LEVEL PATTERN FEATURING A RIDGE OUT
WEST AND TROUGH OVER THE EAST SUGGESTS THAT TEMPS FOR THE EARLY
TO MIDDLE PORTION OF NEXT WEEK WILL LIKELY AVERAGE A LITTLE BELOW
NORMAL WITH A CONTINUED CHC FOR A FEW SHOWERS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 713 AM EDT THU JUL 30 2015
THE MAIN ISSUE FOR AVIATION INTERESTS TODAY IS THE WINDS. EXPECT
WESTERLY SFC WINDS TO BE SUSTAINED AROUND 15 KNOTS BY NOON WITH
GUSTS REACHING 25 KNOTS THIS AFTERNOON. SFC WINDS WILL DIMINISH
BELOW 10 KNOTS AFTER SUNSET. CLR/VFR CONDITIONS WILL CONTINUE
TODAY AND TONIGHT AND THIS IS HIGH CONFIDENCE DUE TO THE VERY DRY
AIR MASS IN PLACE.
&&
.MARINE...
ISSUED AT 330 AM EDT THU JUL 30 2015
WE ARE STILL LOOKING AT A BORDERLINE SMALL CRAFT ADVISORY/BEACH
HAZARD STATEMENT TODAY. LACK OF COLD ADVECTION SHOULD KEEP THINGS
FROM GETTING TOO OUT OF HAND. THE LATEST RUC WIND GUIDANCE HAS
THE STRONGEST WINDS OVER LK MI OCCURRING THIS MORNING... OUT OF
THE WEST-NORTHWEST... THEN DECREASING AFTER THAT WHILE ACTUALLY
BACKING TO THE SOUTHWEST.
THE IDEA IS THAT ONCE THE STRONGER HEATING AND DEEPER MIXING
COMMENCES OVER THE LAND AREAS THIS AFTERNOON WE END UP SEEING A
REVERSAL IN THE LAND/LAKE PRESSURE AND WIND REGIME... LEADING TO
A DECREASING TREND OVER THE WATER WHILE INCREASING OVER THE LAND.
LATEST BUOY OBSERVATIONS SHOW SOLID 3 FOOTERS OCCURRING AT 3 AM AND
WAVE MODEL GUIDANCE SUGGESTS A BRIEF SPIKE TO AROUND 4 FEET BETWEEN
ABOUT 6 AM AND NOON. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS AND
POST HEADLINES IF BUOY WAVE HEIGHTS CONTINUE TO TREND UP.
&&
.FIRE WEATHER...
ISSUED AT 713 AM EDT THU JUL 30 2015
THE COMBINATION OF DRY FUELS... WARM TEMPERATURES IN THE LOWER TO
MID 80S... A DRY AIR MASS... AND GUSTY WEST WINDS WILL RESULT IN
AN ELEVATED FIRE DANGER OVER THE NEXT FEW DAYS. RAIN CHANCES ARE
EXTREMELY LOW THROUGH SATURDAY AND IT HAS BEEN PREDOMINATELY DRY
FOR THE PAST 10 DAYS.
&&
.HYDROLOGY...
ISSUED AT 1232 PM EDT THU JUL 30 2015
RIVER LEVELS CONTINUE TO FALL AND ARE EXPECTED TO CONTINUE TO FALL
FOR AT LEAST THE NEXT WEEK AS RAINFALL AMOUNTS ARE NOT EXPECTED TO
BE ENOUGH TO CAUSE THE RIVERS TO START RISING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 4 PM EDT THIS AFTERNOON FOR MIZ037-
043-050-056-064-071.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LMZ844>849.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...LAURENS
AVIATION...MEADE
FIRE WEATHER...MEADE
HYDROLOGY...WDM
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
334 PM EDT THU JUL 30 2015
.SYNOPSIS...
LOW PRESSURE OFF THE SOUTHEAST COAST WILL SLOWLY SHIFT TO THE
NORTHEAST AWAY FROM THE AREA AS A COLD FRONT MOVES INTO THE AREA
FRIDAY. THIS FRONT WILL STALL OVER THE WEEKEND BEFORE DISSIPATING
EARLY NEXT WEEK. BERMUDA HIGH PRESSURE WILL EXPAND WESTWARD TUESDAY
THROUGH THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 330 PM THURSDAY...LOW PRESSURE IS LOCATED A LITTLE OVER 200
MILES EAST OF BEAUFORT SOUTH CAROLINA. THIS LOW HAS BEEN BATTLING
DRY AIR IMPINGING ON THE CIRCULATION FROM THE NORTH. THIS...PLUS
NORTHEASTERLY SHEAR HAS PREVENTED SIGNIFICANT DEEPENING VIA WARM
CORE/TROPICAL PROCESSES. THE 12Z GFS AND NAM APPEAR FAR TOO EAGER
TO ABSORB THE LOW AND MID LEVEL CIRCULATION WITHIN THE BROADER
WIND FIELD AROUND THE COLD FRONT APPROACHING FROM THE WEST
TONIGHT. THE 17Z RUN OF THE RUC APPEARS MUCH MORE REASONABLE AS
ITS INITIALIZED POSITION OF THE LOW IS MUCH CLOSER TO WHERE IT
APPEARS ON VISIBLE SATELLITE. COMPARED TO THE NAM AND GFS THIS
MEANS A SLOWER VEERING OF SURFACE WIND DIRECTIONS...LIGHTER
OVERALL WIND SPEEDS...AND A DELAY IN ANY PRECIPITATION CHANCES
NEAR THE COAST UNTIL AFTER MIDNIGHT.
ISOLATED SHOWERS ACROSS PENDER COUNTY SHOULD DIE A QUICK DEATH OVER
THE NEXT FEW HOURS AS DRY AIR ALOFT WINS THE GAME. FARTHER INLAND
WHERE BETTER MOISTURE EXISTS WITHIN THE 850-700 MB LAYER...SCATTERED
SHOWERS AND EVEN A FEW THUNDERSTORMS ARE POSSIBLE NEAR AND WEST OF
I-95 THROUGH THE LATE AFTERNOON. THESE SHOWERS AND STORMS WILL
BECOME MORE ISOLATED AFTER SUNSET AS THE SURFACE STABILIZES AND
CONVECTION WILL BE FORCED TO USE 850 MB AS A LIFTING LAYER...WITH
LESS INSTABILITY AND ONLY THE INCOMING FRONT AS A CONVERGENT
BOUNDARY. THE COLD FRONT ITSELF IS MAKING QUICK PROGRESS
SOUTHEASTWARD THROUGH WESTERN VIRGINIA AND NORTH CAROLINA...AND
SHOULD BE NEAR THE COAST AT SUNRISE FRIDAY.
LOWS SHOULD FALL INTO THE 72-76 RANGE OVERNIGHT...NOT AS COOL AS ONE
MIGHT THINK WITH AN INCOMING FRONT. A FEW MORE CLOUDS THAN WE SAW
THIS MORNING PLUS LOW-LEVEL MOISTURE POOLED NEAR THE BOUNDARY SHOULD
PREVENT TEMPS FROM FALLING TOO FAR.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 330 PM THURSDAY...A COLD FRONT WILL SHIFT OVER THE FORECAST
AREA ON FRIDAY AND WILL REMAIN THROUGH THE PERIOD.THE MOISTURE
WILL INCREASE BUT A VERY TIGHT GRADIENT WILL BE SEEN WITH +2 INCH
PW ALONG THE COAST TO 1.5 INCHES WEST OF INTERSTATE 95. MODELS ARE
SHOWING THE BEST CONVECTION FROM 15 UTC INTO THE OVERNIGHT HOURS
WITH A 50% CHANCE OF THUNDERSTORMS ESPECIALLY OVER THE EAST HALF
OF THE FORECAST AREA. THE CONVECTION CHANCES WILL SLOWLY BACK TO
30 PERCENT BY LATE SATURDAY NIGHT. HIGHS WILL RANGE FROM THE MID
90S INLAND UNTIL THE CLOUD COVER AND CONVECTION BEGINNING AND TO
THE UPPER 80S AT THE BEACHES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 330 PM THURSDAY...UNSETTLED WEATHER TO START THE PERIOD WILL
GIVE WAY TO WARMING TEMPERATURES THROUGH THE MIDDLE OF NEXT WEEK.
STALLED COLD/STATIONARY FRONT WILL BE IN THE VICINITY
SUNDAY...PROBABLY ALIGNED RIGHT ALONG OR JUST OFF THE COAST...BEFORE
WASHING OUT AND DISSIPATING ON MONDAY. VERY HIGH PWATS AND SOME
TROPICAL MOISTURE WILL BE LURKING JUST OFF THE COAST...SO AS THIS
FRONT LIFTS BACK NORTH MONDAY AND FALLS APART...INCREASING PRECIP
CHANCES WILL OVERSPREAD THE AREA FROM SE TO NW. HOWEVER...THE BULK
OF THIS PRECIP IS STILL EXPECTED TO REMAIN OFFSHORE. HOWEVER...WILL
CONTINUE THE MDT-CHC POP ALONG THE COAST WITH LOW-CHC INLAND FOR
SUN/MON ALONG WITH TEMPS AROUND NORMAL FOR EARLY AUGUST.
THEREAFTER...LARGE RIDGE ACROSS THE SOUTHERN TIER WILL EXPAND NE
INTO WEDNESDAY BRINGING REDUCED PRECIP CHANCES LOCALLY...BUT WITH
TEMPS RISING TO ABOVE NORMAL ONCE AGAIN. THIS HEAT MAY BE SHORT
LIVED THOUGH AS A COLD FRONT IS PROGGED TO PUSH SOUTH
THURSDAY...WITH VERY DEEP TROUGHING IN ITS WAKE ACROSS THE EASTERN
CONUS. THIS WILL BRING COOLER TEMPS AND ONCE AGAIN INCREASED PRECIP
CHANCES AT THE END OF THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/... AS OF 18Z...LFC`S
COMING DOWN NORTH OF THE REGION. MAY SEE CONVECTION IN PENDER AND
NEW HANOVER COUNTIES THIS AFTERNOON...BUT WILL STICK WITH VCSH DUE
TO COVERAGE AND INTENSITY. MAINLY AN EAST NORTHEAST WIND THIS
AFTERNOON ALONG THE COAST...LIGHT INLAND. TONIGHT...THE NAM WANTS
TO KEEP CONVECTION GOING AS THE FRONT LAYS OVER THE CWA. DUE TO
LACK OF FORCING...SHOULD SEE CONVECTION ENDING FOR DIURNAL REASONS
AFTER 02Z WITH ONLY ISOLATED ACTIVITY OVERNIGHT. FRIDAY...EXPECT
CONVECTION TO FIRE FAIRLY EARLY...MAINLY OVER THE EASTERN HALF OF
THE REGION. POST FRONTAL LIGHT NORTHERLY FLOW IS FORECAST.
EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH A
SLIGHT CHANCE AFTERNOON SHRA/TSRA. BEST CHANCE SHRA/TSRA FRIDAY AND
SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 330 PM THURSDAY...LOW PRESSURE IS LOCATED A LITTLE OVER 200
MILES EAST OF BEAUFORT SOUTH CAROLINA. THIS LOW HAS BEEN BATTLING
DRY AIR INPINGING ON THE CIRCULATION FROM THE NORTH. THE 12Z GFS
AND NAM MODELS APPEAR FAR TOO EAGER TO ABSORB THE LOW INTO THE
COLD FRONT APPROACHING FROM THE WEST TONIGHT. THE 17Z RUN OF THE
RUC MODEL APPEARS MUCH MORE REASONABLE AS ITS INITIALIZED POSITION
OF THE LOW IS MUCH CLOSER TO WHERE IT APPEARS ON VISIBLE
SATELLITE. COMPARED TO THE NAM AND GFS THIS MEANS A SLOWER VEERING
OF SURFACE WIND DIRECTIONS...LIGHTER OVERALL WIND SPEEDS...AND A
DELAY IN ANY PRECIPITATION CHANCES NEAR THE COAST UNTIL LATE
TONIGHT.
SEAS CURRENTLY RANGE FROM 2-3 FEET INSIDE 20 MILES FROM SHORE...TO
AS HIGH AS 4 FEET OUT AT THE FRYING PAN SHOALS BUOY. THE WAVE
SPECTRUM IS DOMINATED BY SWELL ENERGY AT AROUND 7-8 SECONDS PERIOD.
THIS SOUTHEASTERLY SWELL IS BEING GENERATED BY THE LOW OFF THE SOUTH
CAROLINA COAST...AND SHOULD REMAIN THE DOMINANT WAVE SET TONIGHT.
SOME OF THESE 4-FOOTERS SHOULD MAKE IT INSIDE THE COASTAL WATERS
TONIGHT...ESPECIALLY NEAR CAPE FEAR.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 PM THURSDAY...A COLD FRONT WILL STALL ALONG THE COAST
AND WINDS AREA EXPECTED TO REMAIN AT 10 KNOTS OR LESS AND
DIRECTIONS WILL BE VARIABLE OVER THE PERIOD. SEA HEIGHTS ARE
EXPECTED TO RANGE BETWEEN 2 AND 3 FEET WITH A FEW 4 FOOTERS AT 20
MILES OF THE COAST MAINLY FROM FRYING PAN SHOALS NORTHWARD.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 330 PM THURSDAY...WEAKENING COLD FRONT WILL DISSIPATE JUST
INLAND FROM THE COASTAL WATERS SUNDAY INTO MONDAY...ALLOWING FOR
BERMUDA HIGH PRESSURE TO ONCE AGAIN BECOME THE DOMINANT SYNOPTIC
FEATURE. THIS WILL CREATE SW WINDS OF 10-15 KTS...WHICH WILL BE
PERSISTENT WITH LITTLE FLUCTUATION THROUGH THE PERIOD. WAVE
AMPLITUDES WILL INCREASE...ESPECIALLY EARLY NEXT WEEK...AS A
FAIRLY SIGNIFICANT SOUTHERLY SWELL OF 5-6 FT ENTERS THE SPECTRUM
AND COMBINES WITH THE SW WIND CHOP TO PRODUCE 4-5 FT SEAS MONDAY
AND TUESDAY...AFTER BEING 3-4 FT ON SUNDAY.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 PM FRIDAY...ONSHORE WINDS ARE PRODUCING A SMALL 0.5 TO 0.6
FOOT POSITIVE TIDAL ANOMALY AT THE BEACHES. LARGE TIDAL RANGES
ASSOCIATED WITH THE FULL MOON PLUS THIS ANOMALY WILL PUSH WATER
LEVELS TO WITHIN ABOUT 4 INCHES OF MINOR COASTAL FLOODING CRITERIA
AT BOTH WRIGHTSVILLE BEACH AND MYRTLE BEACH THIS EVENING. NO COASTAL
FLOOD ADVISORY IS PLANNED...HOWEVER ALONG THE LOWER CAPE FEAR RIVER
AT DOWNTOWN WILMINGTON WHERE THE OBSERVED ANOMALY IS CLOSER TO +0.8
FEET WE SHOULD ECLIPSE MINOR FLOOD CRITERIA HERE. A COASTAL FLOOD
ADVISORY HAS BEEN ISSUED FOR LOW-LYING AREAS NEAR THE RIVER BETWEEN
8-11 PM.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY FROM 8 PM TO 11 PM EDT THIS EVENING FOR
NCZ107.MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...DRH
LONG TERM...JDW
AVIATION...HDL/TRA
TIDES/COASTAL FLOODING...TRA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
130 PM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 1200 PM THURSDAY...
AN UPPER LEVEL RIDGE IS EXPECTED TO PERSIST OVER THE WESTERN CONUS
THROUGH THE EXTENDED PERIOD...WITH THE RIDGE UNDERGOING FURTHER
AMPLIFYING OVER THE ROCKIES BY EARLY NEXT WEEK. DOWNSTREAM IN THE
CAROLINAS AND MID-ATLANTIC...PERSISTING TROUGHING /CYCLONIC FLOW/
ALOFT WILL PREVAIL. THOUGH NUMEROUS SMALL AMPLITUDE DISTURBANCES
/SHORTWAVES/ WILL NO DOUBT BE PRESENT IN THIS AMPLIFIED PATTERN...
THE BULK OF NORTH CAROLINA IS EXPECTED TO REMAIN ALONG/WEST THE BASE
OF THE UPPER LEVEL TROUGH AXIS...WHERE MOISTURE WILL BE LESS
FAVORABLE FOR (OR PERHAPS INSUFFICIENT TO SUPPORT) DIURNAL
CONVECTION...EXCEPT IN EASTERN/COASTAL PORTIONS OF THE CAROLINAS.
WILL MAKE LITTLE CHANGE TO THE PREVIOUS FORECAST INDICATING HIGHS IN
THE LOWER TO MID 90S...LOWS IN THE LOWER 70S...AND DIURNAL PRECIP
CHANCES CONFINED PRIMARILY TO THE SE COASTAL PLAIN. IT SHOULD BE
NOTED THAT A WESTWARD SHIFT IN THE UPPER LEVEL PATTERN (RIDGE/TROUGH
AXES) OVER THE LOWER 48 WOULD RESULT IN INCREASED PRECIP CHANCES
ACROSS PORTIONS OF CENTRAL NC...PARTICULARLY ALONG/EAST OF HWY 1...
THOUGH NO SIGNIFICANT CHANGE IS APPARENT AT THIS TIME. -VINCENT
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 130 PM THURSDAY...
ISOLATED PREFRONTAL SHOWERS AND A FEW TSTMS HAVE DEVELOPED ACROSS
THE WESTERN PIEDMONT...AND MAY PRESENT A BRIEF AVIATION CONCERN THIS
AFTERNOON SHOULD THEY PASS OVER ANY OF THE SITES. IMPACTS WOULD BE
BRIEF PERIOD OF IFR CIGS/VSBY...AND WIND GUSTS AS HIGH AS 30KT. THE
RISK FOR SUCH ACTIVITY WILL SHIFT EAST TOWARD OUR EASTERN TAF SITES
LATER TODAY. OTHERWISE...THE COLD FRONT IS STILL ON TRACK TO MOVE
ACROSS CENTRAL NC LATE THIS EVENING AND OVERNIGHT...SO THE RISK FOR
THE AFOREMENTIONED ISOLATED SHOWERS/TSTMS WILL CONTINUE UNTIL THE
FRONT MOVES THROUGH. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND
THE FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA OVERNIGHT. VFR
CONDITIONS ARE EXPECTED BEHIND THE FRONT LATER TONIGHT AND THROUGH
THE REST OF THE 24 HOUR TAF PERIOD.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST DURING THE
DAYTIME FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS
WEEKEND. ITS WORTH NOTING THAT ANY NORTHWARD SHIFT IN THE PATTERN
MAY RESULT IN WORSE CONDITIONS THAN ARE CURRENTLY FORECAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...VINCENT
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS NORMAN OK
1222 PM CDT THU JUL 30 2015
.UPDATE...
WE HAVE BEEN UPDATING THE FORECAST THROUGH THE MORNING WITH RADAR
AND MESOSCALE MODEL TRENDS. JUST MADE ANOTHER BIG UPDATE FOR NOT
ONLY EXPECTED AFTERNOON POPS... BUT ALSO SIGNIFICANTLY LOWER
FORECAST MAX TEMPS ACROSS NORTHERN OKLAHOMA WHERE CLOUDS AND
PRECIPITATION WILL NOT ALLOW THE POST-FRONTAL AIR TO WARM MUCH
THIS AFTERNOON. GENERALLY POPULATED WITH HOURLY RAP TEMPERATURES
ALTHOUGH DID NOT BRING TEMPS QUITE AS HOT IN THE SOUTH AS RAP.
&&
.PREV DISCUSSION... /ISSUED 609 AM CDT THU JUL 30 2015/
AVIATION...
12Z TAFS... SHOWERS/STORMS WILL BE POSSIBLE IN PARTS OF NORTHERN
OK THIS MORNING. ADDITIONAL ISOLATED TO SCATTERED SHOWERS/STORMS
WILL BE POSSIBLE THIS AFTERNOON AND TONIGHT ACROSS PARTS OF THE
AREA. CHANCES ARE TOO LOW IN SOME AREAS OR AT TIMES FOR A MENTION
IN TAFS. GUSTY VARIABLE WINDS WILL BE POSSIBLE NEAR THE STORMS.
MOSTLY MVFR AND VFR CEILINGS ARE EXPECTED THROUGH THE TAF PERIOD.
PREV DISCUSSION... /ISSUED 345 AM CDT THU JUL 30 2015/
DISCUSSION...
SCATTERED SHOWERS/STORMS ARE BEGINNING TO DEVELOP SOUTHWEST FROM A
CLUSTER OF STORMS IN S KS ACROSS THE PANHANDLES TOWARDS A LARGER
AREA OF STORMS IN EASTERN NM EARLY THIS MORNING. THIS ACTIVITY COULD
EVENTUALLY MOVE/DEVELOP INTO PORTIONS OF THE FA THIS MORNING.
ADDITIONAL ISOLATED TO SCATTERED STORMS WILL BE POSSIBLE THIS
AFTERNOON WITH THE FRONTAL BOUNDARY AND ANY LINGERING OUTFLOW
BOUNDARIES ACROSS THE FA BEING FOCI. THE BEST CHANCE MAY ACTUALLY BE
IN CENTRAL AND/OR SOUTHERN SECTIONS OF THE FA WHERE LESS CLOUD COVER
IS EXPECTED SO MORE SFC HEATING WOULD LIKELY OCCUR.
MODELS STILL SHOW THE CENTER OF THE UPPER HIGH SLOWLY MOVING WEST
WITH NW FLOW POSSIBLY DEVELOPING OVER PORTIONS OF THE FA AND MID-
LEVEL DISTURBANCES MOVING THROUGH THE FLOW. SHOWERS AND
THUNDERSTORMS WILL REMAIN POSSIBLE ACROSS PARTS OF THE FA AT LEAST
THROUGH THE WEEKEND AND POSSIBLY INTO EARLY NEXT WEEK. THE GFS SHOWS
THE UPPER HIGH TRYING TO BUILD BACK TO THE EAST INTO THE REGION THE
MIDDLE OF NEXT WEEK ALTHOUGH THE HIGH PRESSURE CENTER REMAINS TO THE
WEST AND THE RIDGE IS NOT AS STRONG AS HAS THE PAST WEEK. MEANWHILE
THE ECMWF HOLDS THE CENTER OF THE HIGH FURTHER WEST/SOUTHWEST AND
MAINTAINS SOMEWHAT OF A NW FLOW OVER THE REGION THROUGH NEXT WEEK.
IF THE GFS IS RIGHT THE CHANCES FOR RAIN WOULD BE LESSER THAN THE
ECMWF THROUGH NEXT WEEK BUT NEITHER IS ZERO FOR ANY LONG PERIOD OF
TIME AS DISTURBANCES CONTINUE TO MOVE THROUGH THE FLOW.
HOT AND HUMID CONDITIONS WILL OCCUR AGAIN TODAY ACROSS PARTS OF THE
FA. TRIPLE DIGIT HEAT INDICES WILL BE LIKELY IN SOUTHERN OKLAHOMA
AND WESTERN NORTH TEXAS. A FEW PLACES IN SE PARTS OF THE FA COULD
REACH 105 HEAT INDEX VALUES BUT THIS IS A BIT UNCERTAIN SO WILL
LEAVE FOR THE DAY SHIFT TO KEEP AND EYE ON AND NOT ISSUE A HEAT
ADVISORY AT THIS TIME. TEMPS WILL REMAIN SLIGHTLY COOLER /80S TO LOW
90S/ THROUGH THE WEEKEND BEFORE WARMING BACK INTO THE MID AND UPPER
90S NEXT WEEK. THIS WILL LIKELY LEAD TO A RETURN OF THE TRIPLE DIGIT
HEAT INDICES FOR AT LEAST PARTS OF THE FA NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 95 72 87 71 / 30 30 30 10
HOBART OK 96 72 90 71 / 40 30 30 30
WICHITA FALLS TX 100 76 95 73 / 20 20 30 20
GAGE OK 81 68 87 67 / 80 30 30 20
PONCA CITY OK 89 69 89 70 / 80 20 20 10
DURANT OK 101 75 93 73 / 20 30 30 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION...UPDATED
NWS TULSA OK
1207 PM CDT THU JUL 30 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 18Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL SITES
THROUGHOUT THE 24 HOUR FORECAST PERIOD. THUNDERSTORM CHANCES WILL
INCREASE ACROSS THE AREA THIS AFTERNOON AND OVERNIGHT. HOWEVER...
OVERALL LOW CHANCES AND EXPECTED LOW COVERAGE WILL PRECLUDE
MENTIONING IN ANY PARTICULAR TAF.
&&
.PREV DISCUSSION... /ISSUED 1051 AM CDT THU JUL 30 2015/
..UPDATE...
DISCUSSION...
THUNDERSTORMS MADE A RUN AT THE NORTHWESTERN PORTION OF THE
FORECAST AREA THIS MORNING. WE RAISED POPS IN REACTION TO THIS
FROM ABOUT TULSA NORTHWESTWARD. CURRENTLY... EASTWARD PROGRESSION
OF PRECIP SEEMS TO BE COMING TO A HALT... IN AGREEMENT WITH THE
HRRR AND RUC MODELS. CLOUD TOPS ARE WARMING RAPIDLY ON THE
EASTERN SIDE OF THE PRECIP SHIELD AS WELL... CONFIRMING THAT THE
THUNDERSTORM ACTIVITY HAS JUST ABOUT REACHED ITS EASTWARD LIMIT.
THAT SAID... AN OUTFLOW BOUNDARY IS RACING EASTWARD ACROSS OSAGE
AND PAWNEE COUNTIES... WHICH MAY BE ENOUGH TO INIATE ISOLATED
CONVECTIVE ACTIVITY. THIS WILL JUSTIFY LEAVING THE HIGHER POPS IN
FOR THE NEXT FEW HOURS. UPDATED PRODUCTS HAVE BEEN SENT.
PREV DISCUSSION... /ISSUED 634 AM CDT THU JUL 30 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
MOIST AND UNSTABLE AIR MASS ACROSS THE REGION ALONG WITH A WEAK COLD
FRONT IN THE PROXIMITY WILL SUPPORT SCATTERED TSRA THROUGH TONIGHT.
ACTIVITY IN SOUTH CENTRAL KS MAY IMPACT BVO/TUL/RVS LATER THIS
MORNING. BEST CHANCES SHOULD BE AT NERN OK SITES THIS AFTERNOON AND
MLC/FSM AFTER 00Z. ALTHOUGH LAYERED CLOUDS WILL BE THE RULE FOR MUCH
OF THIS FORECAST PERIOD...VFR CONDITIONS SHOULD PREVAIL OUTSIDE OF
TSRA...WHICH WILL REDUCE VSBY TO MVFR.
PREV DISCUSSION... /ISSUED 259 AM CDT THU JUL 30 2015/
DISCUSSION...
WEAK SFC BOUNDARY HAS PUSHED WELL INTO ERN OK THIS MORNING. THIS
FEATURE WILL SERVE AS FOCUS FOR WIDELY SCATTERED TO SCATTERED
CONVECTION TOMORROW AND INTO FRIDAY...ESPECIALLY OVER ERN OK. HEAT
ADVISORY CRITERIA WILL BE FLIRTED WITH ACROSS PARTS OF EAST
CENTRAL AND SOUTHEAST OKLAHOMA. WILL FOREGO AN ADVISORY AT THIS
TIME GIVEN MARGINAL VALUES EXPECTED ALONG WITH THE SHORT DURATION.
MODELS HAVE REMAINED FAIRLY CONSISTENT IN PUSHING THE BOUNDARY
FURTHER WEST BY LATER IN THE DAY FRIDAY...WITH MOST CONVECTION
ACROSS CENTRAL AN WESTERN SECTIONS OF OKLAHOMA. UPPER HIGH TO
REMAINED POSITIONED TO THE WEST OF THE FA THROUGH THE FORECAST
PERIOD...WITH SOME HEIGHT RISES NOTED THROUGH THE WEEKEND PER THE
GFS. LATER IN THE FORECAST CYCLE...ECMWF FLATTENS THE RIDGE AS AS
WAVE TRAVERSES THE CENTRAL PLAINS...WHILE THE GFS MAINTAINS
HIGHER HEIGHTS/WEAK NW FLOW. WILL KEEP FORECAST DRY FOR NOW BEYOND
FRIDAY. TEMPERATURES WILL INCREASE SOME OVER THE WEEKEND...BUT
WILL LIKELY NOT BE AS HOT AS OBSERVED THE LAST WEEK GIVEN THE
POSITIONING OF THE UPPER RIDGE TO THE WEST.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...06
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
136 PM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM...ISOLATED TO WIDELY SCATTERED CONVECTION HAS BEGUN TO
DEVELOP ACRS THE CWFA...IN LINE WITH THE CURRENT POP TRENDS. TEMPS
AND DEWPTS ARE ALSO ON TRACK. SO NO SIGNIFICANT CHANGES WITH THIS
UPDATE.
AS OF 1015 AM...THE 12Z SFC ANALYSIS SHOWED THE COLD FRONT PUSHING
INTO THE SMOKIES AND GREAT TENN VALLEY. THE FRONT WILL CONTINUE TO
PUSH ACRS THE MTNS THRU MIDDAY...THEN ACRS THE PIEDMONT THIS AFTN.
THERE IS LESS CLOUD COVER AT THIS TIME OF DAY THAN THE LAST FEW
DAYS. SO TEMPS ARE WARMING QUICKLY...DESPITE HUMID BL...WITH DEWPTS
STILL IN THE LWR-MID 70S. THIS IS RESULTING IN SBCAPE ALREADY IN THE
1500-2500 J/KG RANGE ON THE SPC MESOANALYSIS PAGE ACRS THE PIEDMONT.
I HAVE BUMPED MAX TEMPS UP A DEG OR TWO GIVEN THE TRENDS. AS FOR
POPS...ONE WOULD EXPECT DECENT COVERAGE OF SHWRS AND TSTMS...GIVEN
DECENT INSTBY AND A BOUNDARY WORKING THRU THE AREA. HOWEVER...THE
LATEST CAMS ARE A BIT MUTED. I TRIED BLENDING IN CAM POP...BUT THAT
DROPPED POP DOWN ACRS MUCH OF THE AREA. SO I PRETTY MUCH KEPT POPS
AS IS...WHICH IS IN THE 30-40 PCT RANGE. SEVERE THREAT IS STILL
MARGINAL...WITH WIND BEING THE MAIN THREAT.
AS OF 650 AM...THE FORECAST APPEARS IN GOOD SHAPE. I WILL TAYLOR
POPS TO REFLECT LIGHT RETURNS OVER THE WESTERN NC MTNS. IN
ADDITION...I WILL REDUCE FOG MENTION.
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AT KCLT...A RATHER WEAK AND NEBULOUS COLD FRONT WILL CROSS THE KCLT
AREA THIS EVENING. IT IS HELPING TO INITIATE CONVECTION ACRS THE
BLUE AND NC FOOTHILLS N OF KCLT...AND THAT ACTIVITY WILL DRIFT SOUTH
ACRS THE AREA BETWEEN 19-22Z. GUIDANCE HAS SOME ISOLATED CONVECTION
DEVELOPING ALONG THE TRAILING FRONT AFTER 00Z THIS EVENING ACRS THE
NC PIEDMONT. CONFIDENCE IS LOW ON THIS...AS DRY AIR WILL BEGIN TO
FILTER IN AND THE BL WILL BE STABILIZING. SO WILL NOT MENTION ANY
PRECIP BEYOND THE TEMPO. OVERNIGHT...THERE IS BETTER AGREEMENT ON
LINGERING VFR STRATOCU WELL INTO THE NIGHT...AS MOISTURE LINGERS
BELOW A DEVELOPING INVERSION AROUND 5000-7000 FT AGL. DRY AIR WILL
EVENTUALLY CLEAR THIS OUT FRIDAY MORNING. WINDS ARE ALREADY FAVORING
A N DIRECTION AHEAD OF THE FRONT...AND WILL CONTINUE TO THRU THE
PERIOD...INCREASING BEHIND THE FRONT TO AROUND 8-10 KTS BEFORE
DAYBREAK FRIDAY.
ELSEWHERE...SCATTERED CONVECTION THIS AFTN SEEMS TO WARRANT VCTS FOR
ALL SITES. CLOUD BASES WILL HOVER AROUND 4500-6000 FT...THEN LIFT TO
AROUND 7000-8000 FT BEHIND A PASSING COLD FRONT THIS EVENING. THE
NAM HAS POTENTIAL MVFR CIGS AT KAVL FOR A BRIEF TIME THIS
EVENING...SO WILL MENTION SCT FOR NOW. A N WIND WILL INCREASE
SLIGHTLY OVERNIGHT...WITH DRY AIR WORKING IN. SO NOT EXPECTING ANY
FOG OR LOW CLOUDS OUTSIDE THE LITTLE TN RIVER VALLEY. THE VFR-LVL
STRATOCU IS EXPECTED TO DISSIPATE FRIDAY MORNING.
OUTLOOK...DRY HIGH PRESSURE WITH BUILD IN ACRS THE REGION
FRIDAY...ALLOWING FOR GENERALLY DRY AND QUIET WEATHER THROUGH THE
WEEKEND. A GRADUAL INCREASE IN CHANCES FOR SHOWERS/THUNDERSTORMS AND
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% LOW 56% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
142 PM CDT THU JUL 30 2015
.SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
A VERY ISOLATED SHOT AT THUNDERSTORMS WILL BE POSSIBLE TONIGHT AS
ENERGY AND MOISTURE WILL BE MOVING IN FROM THE EAST DUE TO A COLD
FRONT PROGRESSING SOUTHWARD ACROSS THE SE CONUS. WITH THE UPPER
LEVEL STEERING WINDS BEING NORTHEAST AND EAST...SOME OF THE SHOWER
AND STORM DEVELOPMENT IN THE HI RES MODELS COULD MAKE IT AS FAR
WEST AS THE EASTERN PERIPHERY OF THE CWA. HOWEVER...AN APPRECIABLE
MOISTURE GRADIENT OVER BASICALLY THE I35 CORRIDOR SHOULD PREVENT
MUCH FROM GETTING ANY FARTHER WESTWARD. ALSO...DRY LOW LEVEL
CONDITIONS AS SEEN ON LAPS AND RUC SOUNDINGS WOULD CHALLENGE ANY
PRECIPITATION FROM REACHING THE SURFACE SO CONFIDENCE IS NOT HIGH
FOR MEASURABLE PRECIP THIS EVENING. THEREFORE LEFT THE ISOLATED
MENTION IN FOR THE EASTERNMOST AREAS OF THE CWA.
SHOULD SEE SOME SCATTERED LOW CLOUD DEVELOPMENT IN THE MORNING BUT
LESS THAN NORMAL WITH LIGHT AND VARIABLE WINDS. THE LIGHT WINDS
AND MOSTLY UNOBSTRUCTED SKY SHOULD KEEP LOWS A COUPLE DEGREES
BELOW GUIDANCE AS THEY WERE THIS MORNING.
BEST SHOT AT MEASURABLE PRECIP WILL BE IN THE AFTERNOON FRIDAY AS
THE CONTINUING WEST COLD FRONT INTERACTS WITH THE COASTAL PLAINS
SEA BREEZE. AN AREA OF ENHANCED QPF WAS NOTED IN THE NAM AND GFS
WHICH MAKES SENSE AS AN AREA OF LIFT ENOUGH TO REALIZE DECENT
INSTABILITY DURING THE AFTERNOON HOURS. STILL THINK PWATS ARE A
BIT EXAGGERATED IN THE FORECAST SOUNDINGS BUT STILL THINK A
BRIEFLY HEAVY DOWNPOUR AND GUSTY WINDS ARE STILL IN PLAY TOMORROW
AFTERNOON.
&&
.LONG TERM (SATURDAY THROUGH THURSDAY)...
MODELS ARE TRENDING A BIT DRIER OVER THE WEEKEND BUT WITH THE BEST
OPPORTUNITY FOR SOUTH CENTRAL TEXAS TO RECEIVE RAINFALL BEING
SATURDAY AS A FORECAST COMPLEX DEVELOPS IN THE PANHANDLE AND
NORTHERLY UPPER LEVEL FLOW CARRIES IT SOUTHWARD. UNSURE ABOUT HOW
FAR SOUTH THIS WILL BE ABLE TO MAKE IT BUT CONDITIONS ARE
FAVORABLE FOR A WELL SUSTAINED COLD POOL SHOULD AN ORGANIZED
SYSTEM DEVELOP. THEREFORE HIGHLIGHTED THE NORTHERN PERIPHERY OF
THE CWA ON THE PLATEAU FOR THE BEST SHOT AT RAINFALL SATURDAY.
AFTERWARDS...THE UPPER LEVEL PATTERN RETURNS TO THE SUMMER
DOLDRUMS OF HOT AND DRY THROUGH THE END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 76 100 76 100 76 / 10 30 20 20 0
AUSTIN BERGSTROM INTL AIRPORT 72 99 74 99 73 / 10 30 20 20 0
NEW BRAUNFELS MUNI AIRPORT 74 101 76 100 74 / 10 30 20 20 10
BURNET MUNI AIRPORT 74 99 75 98 74 / 10 30 20 20 -
DEL RIO INTL AIRPORT 75 101 78 101 78 / - 10 20 20 10
GEORGETOWN MUNI AIRPORT 74 100 75 98 74 / 10 30 20 20 0
HONDO MUNI AIRPORT 71 98 76 100 75 / 10 30 20 20 10
SAN MARCOS MUNI AIRPORT 75 98 76 99 75 / 10 30 20 20 10
LA GRANGE - FAYETTE REGIONAL 76 99 76 99 75 / 20 30 20 10 10
SAN ANTONIO INTL AIRPORT 76 99 78 99 77 / 10 30 20 20 10
STINSON MUNI AIRPORT 74 100 77 100 76 / 10 30 20 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...04
SYNOPTIC/GRIDS...TB3
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1248 PM CDT THU JUL 30 2015
.DISCUSSION...
PLEASE SEE 18Z AVIATION DISCUSSION...
&&
.AVIATION...
VFR CONDITIONS TO PREVAIL FOR THE NEXT 24 HOURS. A FEW ISOLATED
SHOWERS ARE POSSIBLE THIS AFTERNOON MOSTLY TO THE EAST OF HIGHWAY
59. DROPPED MENTION OF TSRA IN TAFS BECAUSE STRONG SUBSIDENCE
OVER THE AREA IS LIMITING CONVECTION. WINDS WILL BE FROM THE N-NE
AT 5 TO 10 KNOTS. 44
&&
.PREV DISCUSSION... /ISSUED 904 AM CDT THU JUL 30 2015/
DISCUSSION...
SEEING MORE CLOUD COVER ACROSS EASTERN AREAS THIS AM AS DEEPER
MOISTURE ADVECTS IN FROM THE EAST. QUITE A DIFFERENCE
BETWEEN THE 12Z LCH AND CRP SOUNDINGS (2.2 VS. 1.5 INCH
PRECIPITABLE WATER). GIVEN THIS DEEPER MOISTURE ACROSS EASTERN
AREAS...AND THE LATEST HRRR REFLECTIVITY FORECAST...BELIEVE THAT
THE CHC POP ACROSS THE EAST AND SLIGHT CHC POP ACROSS THE WEST IS
ON TRACK FOR THIS AFT/EVE. MAX TEMPS NEAR 100 INLAND AND LOWER TO
MID 90S COAST APPEARS ON TRACK AS WELL. NO SIGNIFICANT CHGS TO
THE ONGOING FCST. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 99 76 101 76 / 20 30 10 10 10
HOUSTON (IAH) 78 98 76 100 76 / 30 30 20 20 10
GALVESTON (GLS) 82 92 81 92 82 / 30 30 20 20 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...33
AVIATION/MARINE...44
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1241 PM CDT THU JUL 30 2015
.AVIATION... /FOR THE 18Z TAFS/
MVFR CEILINGS WILL LINGER FOR AT LEAST A COUPLE MORE HOURS AT
KGUY...OTHERWISE VFR CONDITIONS HAVE RETURNED AT KDHT AND KAMA.
ISOLATED TO SCATTERED THUNDERSTORMS SHOULD DEVELOP WITH DIURNAL
DESTABILIZATION BY LATE AFTERNOON OR EARLY EVENING BUT PROBABILITY OF
EITHER OF THE THREE TERMINALS BEING IMPACTED IS LOW UNTIL MORE
ORGANIZED THUNDERSTORM COMPLEX DEVELOPS LATER THIS EVENING. ALTHOUGH
SOMEWHAT CONDITIONAL...CURRENT FORECAST IS FOR A PERIOD OF
THUNDERSTORMS BEGINNING MID EVENING AND LASTING FOR A FEW HOURS
BEFORE PROBABILITIES DECREASE NECESSITATING A PROB30 GROUP THROUGH
EARLY MORNING. WINDS TOMORROW MORNING ARE ALSO CONDITIONAL ON
THUNDERSTORM COMPLEX DEVELOPMENT AND ARE MORE NORTHWESTERLY THAN
CURRENT GUIDANCE INDICATES. AMENDMENTS WILL PROBABLY BE NEEDED
THROUGH THE EVENING.
BRB
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT THU JUL 30 2015/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
17/15
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
310 PM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL SLIDE EAST ACROSS OUR REGION TONIGHT...STALLING
ALONG THE SOUTHEAST COAST FRIDAY INTO SATURDAY. THIS WILL ALLOW
FOR HIGH PRESSURE TO KEEP MOST OF THE AREA DRY THROUGH THE
WEEKEND...AS IT MOVES IN FROM THE WEST.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 310 PM EDT THURSDAY...
SCATTERED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN THE UNSTABLE
AIR AHEAD AND ALONG THE COLD FRONT THIS AFTERNOON. THE STORM
PREDICTION CENTER IN THEIR DAY 1 CONVECTIVE OUTLOOK HAS REMOVED THE
MARGINAL RISK AREAS FROM OUR COUNTY WARNING AREA...LEAVING US IN THE
GENERAL THUNDERSTORM AREA. THE COLD FRONT ALONG THE MOUNTAINS
THIS AFTERNOON WILL MOVE EAST THIS EVENING INTO TONIGHT. LOOKING
AT THE LATEST SPC MESOSCALE ANALYSIS...THE RICHEST CAPES AROUND 2K
J/KG AND SFC BASED LIS AROUND MINUS 5 WHERE EAST OF THE BLUE RIDGE
MOUNTAINS. HOWEVER...THE BEST DYNAMICS AND MOISTURE CONVERGENCE
WILL REMAIN NORTH OF OUR AREA. LEANED POPS THIS AFTERNOON INTO
TONIGHT TOWARDS THE LATEST HRRR WITH JUST A SLIGHTLY SLOWER TIMING
AND KEPT THE HIGHEST CHANCES IN THE EAST.
DRIER AIR OVERSPREADING OUR WESTERN CWA TONIGHT...WHILE THE FRONT
SLOWS DOWN IN THE EAST AND KEEPS THE HIGHER DEWPOINTS LINGERING
LONGER. SHOWERS AND THUNDERSTORMS SHOULD MOVE OUT OF THE PIEDMONT BY
MIDNIGHT...WITH SKIES CLEARING. LIGHT WINDS AND LOW LEVEL MOISTURE
MAY RESULTS IN SOME PATCHY VALLEY FOG OVERNIGHT INTO FRIDAY MORNING.
LOW TEMPERATURES TONIGHT WILL RANGE FROM THE LOWER TO MID 50S IN THE
DEEPER VALLEYS OVER SOUTHEAST WEST VIRGINIA AND FAR SOUTHWEST
VIRGINIA TO THE LOWER TO MID 60S IN THE PIEDMONT.
HIGH PRESSURE BUILDS EASTWARD FROM THE CENTRAL PLAINS FRIDAY. THE
HIGH CENTER WILL BRING WITH IT DRIER AIR...PUSHING DEWPOINTS INTO
THE 50S AND LOWER 60S. THE LOWER RELATIVE HUMIDITIES WILL BE A
WELCOME CHANGE FOR MANY. HIGH TEMPERATURES FRIDAY AFTERNOON WILL
BE IN THE MID 70S IN THE NORTHWEST MOUNTAINS TO AROUND 90 DEGREES
IN THE PIEDMONT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 215 PM EDT THURSDAY...
A QUIET AND RATHER COMFORTABLE PERIOD LOOKS IN STORE UNDER BROAD UPPER
TROFFINESS ENHANCED VIA SURFACE HIGH PRESSURE BUILDING OVERHEAD THROUGH
THE WEEKEND. THIS SHOULD RESULT IN MAINLY SUNNY WARM DAYS AND
CLEAR/PLEASANT NIGHTS GIVEN DRIER DEWPOINTS AND SUBSEQUENT LOWER
HUMIDITY THROUGH AT LEAST SUNDAY. ONLY EXCEPTIONS COULD BE WITH MORE
CLOUDS AND POSSIBLY A FEW LIGHT SHOWERS NW UNDER SLIGHTLY BETTER
UPSLOPE LATE SATURDAY...AND THEN PERHAPS OVER THE WESTERN HALF SUNDAY
EVENING WITH A PASSING MID LEVEL SHORTWAVE. HOWEVER GIVEN PROGGED
DRYNESS AND LIKELY ISOLATED NATURE TO ANY SHOWERS OPTING TO LEAVE OUT
ANY POPS OR SHOWER MENTION FOR NOW.
TEMPS LOOK TO REMAIN QUITE PERSISTENT THROUGH THE PERIOD WITH WEAK
DOWNSLOPE/HEATING OF DRY AIR ALLOWING HIGHS TO REMAIN IN THE 85-90
RANGE EAST...AND MOSTLY LOW/MID 80S MOUNTAINS DESPITE THE COOLER/DRIER
AIRMASS. BETTER IMPACT OF THE DRY AIR TO BE FELT DURING THE OVERNIGHTS
WITH LOWS IN THE 50S VALLEYS AND LOW/MID 60S ELSEWHERE. COOLEST NIGHT
AT THIS POINT LOOKS TO BE EARLY SUNDAY WITH THE PASSING OF THE 85H
TROUGH...AND HIGH PRESSURE ABOUT OVERHEAD POSSIBLY ALLOWING A FEW 40S
IN THE DEEPEST NW VALLEYS PENDING ANY RIVER FOG LATE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 1230 PM EDT THURSDAY...
MEAN 5H TROUGH TO REMAIN ACROSS THE MID ATLANTIC REGION THROUGH MUCH OF
NEXT WEEK WITH STEADY NW FLOW ALOFT BETWEEN UPPER LEVEL LOW PRESSURE
WELL TO THE NORTH AND STRONG RIDGING OVER THE SW STATES. THIS SHOULD
ALLOW FOR AN OVERALL PERSISTENCE TYPE FORECAST THROUGH THE EXTENDED
WITH TOLERANT HUMIDITY LEVELS ALONG WITH LOWS MOSTLY IN THE 60S AND
HIGHS 80S TO LOWER 90S. COVERAGE OF SHOWERS AND STORMS ALSO LIKELY
LIMITED PENDING PROGRESSION OF THE NEXT POSSIBLE COOL SURGE LATE IN THE
PERIOD. HOWEVER WILL ALSO HAVE TO WATCH LINGERING MOISTURE WITH THE
RESIDUAL FRONT NEAR THE COAST WHICH COULD BE LIFTED BACK NORTH BY
APPROACH OF WEAK IMPULSES ALOFT ESPECIALLY EARLY NEXT WEEK. THIS ALONG
WITH HEATING MAY BE ENOUGH TO SPARK ISOLATED CONVECTION MAINLY SOUTH
MONDAY...AND ALONG A PASSING SHORTWAVE TROUGH AXIS CROSSING FROM THE NW
TUESDAY...BUT LOW POPS AT BEST BOTH DAYS.
UPPER TROUGH JUST NORTH OF THE LAKES WILL DEEPEN AGAIN BY MIDWEEK AS
MORE SHORTWAVE ENERGY ROTATES THROUGH AND SLIDES AN ASSOCIATED COLD
FRONT SOUTH TOWARD/INTO THE REGION. HOWEVER MODELS DISAGREE ON THE
AMPLITUDE OF THE DIGGING TROUGH WITH THE GFS MOST AGGRESSIVE WHILE
OTHER SOLUTIONS SLOWER/WEAKER WHILE MAINTAINING MORE CONVECTION ALONG
THE BOUNDARY. FOR NOW WILL GO WITH A WEAKER/SLOWER SCENARIO BUT LEAN
TOWARD THE GFS IN DRIVING THE COOL ADVECTION IN BY THE END OF THE
PERIOD SINCE IT HAS BEEN BEST OF LATE.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
AS OF 140 PM EDT THURSDAY...
A COLD FRONT WILL CONTINUE TO MOVE EAST ACROSS THE REGION THIS
AFTERNOON INTO TONIGHT. MVFR SCT TO BKN CLOUDS WITH POCKETS OF
IFR/LIFR IN CONVECTION THIS AFTERNOON INTO THIS EVENING.
WINDS WILL BECOME NORTHWEST AT 5 TO 12 KTS THIS AFTERNOON...THEN
WEAKEN THIS EVENING INTO TONIGHT.
WITH DRIER AIR WORKING IN THE FOG THREAT SHOULD BE MINIMIZED...THOUGH
THERE IS A SMALL CHANCE THAT LWB/BCB COULD FOG IN GIVEN SOME
SLIGHTLY COOLER AIR OVER MOIST GROUND.
BEHIND THE FRONT...DRIER AIR UNDER VFR CONDITIONS EXPECTED
FRIDAY. NORTHWEST WINDS AT 5 TO 12 KTS EXPECTED FRIDAY AFTERNOON.
HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE
PERIOD.
EXTENDED AVIATION FORECAST...
UNDER HIGH PRESSURE...DRY AND VFR FRIDAY NIGHT THROUGH SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KK/WP
NEAR TERM...KK
SHORT TERM...JH
LONG TERM...JH
AVIATION...KK/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
140 PM EDT THU JUL 30 2015
.SYNOPSIS...
A FRONT WILL SLIDE ACROSS OUR REGION TODAY...STALLING ALONG THE
SOUTHEAST COAST FRIDAY INTO SATURDAY. THIS WILL ALLOW FOR HIGH
PRESSURE TO KEEP MOST OF THE AREA DRY THROUGH THE WEEKEND...AS IT
MOVES IN FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM EDT THURSDAY...
MADE SOME MINOR ADJUSTMENTS IN CLOUD COVER AND TEMPERATURES
FOR THIS AFTERNOON.
AS OF 919 AM EDT THURSDAY...
ADJUSTED TEMPERATURES WITH LATEST SFC OBS AND GUIDANCE THIS
MORNING INTO THIS AFTERNOON. KFCX WSR-88D SHOWED SCATTERED
CONVECTION MOVING EASTWARD ACROSS SOUTHEAST WEST VIRGINIA
SOUTHWARD INTO THE WESTERN MOUNTAINS. THIS MORNING 12Z/8AM RNK
SOUNDING INDICATED A NORTHWEST FLOW AND PWATS AROUND 1.5 INCHES.
STILL CAN NOT COMPLETELY RULE OUT LOCALLY HEAVY RAINS AND
ISOLATED THREAT FOR WIND GUSTS WITH STRONGER STORMS GIVEN HIGHER
LOW LEVEL LAPSE RATES COMBINED WITH HIGH MOISTURE CONTENT.
LEANED POPS THIS MORNING INTO THIS AFTERNOON TOWARDS HRRR WHICH
CAPTURED CURRENT RADAR IMAGES THE BEST. MORE CHANGES LATER THIS
MORNING.
AS OF 715 AM EDT THURSDAY...
AREA OF SHOWERS/EMBEDDED THUNDERSTORMS MOVING ACROSS SE WV THIS
MORNING INVOF FRONTAL BOUNDARY. THIS FRONT IS GOING TO SLIDE
SOUTHEAST THROUGH THE DAY...WITH MAIN FOCUS WORKING EAST TOWARD
THE PIEDMONT BY EARLY AFTERNOON. NO MAJOR CHANGES TO THE FORECAST
BEYOND UPDATING CHANCES THROUGH 9 AM INTO THE ALLEGHANYS.
PREVIOUS VALID DISCUSSION...
EXPECT FOG TO BE ERODE OR DISSIPATE BY 13Z.
MODELS ARE SIMILAR IN TIMING OF THE FRONT BUT EXPECT TYPICAL
DIFFERENCES ON WHERE BEST THREAT OF SHOWERS/STORMS WILL BE. GIVEN
THERE WILL BE MORE CLOUDS AROUND IN THE WEST THIS MORNING ALONG WITH
FRONT MOVING IN BY LATE MORNING...THINK THE STORM THREAT IS LOWER
OVER THE MTNS. AS WE HEAD INTO THE AFTERNOON...THE EASTERN CWA
SHOULD HAVE ENOUGH SUN TO STEEPEN THE LOW LVL LAPSE RATES. THOUGH
THE DYNAMICS ARE NOT THAT GREAT WITH THE FRONT...CANNOT RULE OUT THE
ISOLATED THREAT FOR A MICROBURST GIVEN HIGHER LOW LVL LAPSE RATES
COMBINED WITH HIGH MOISTURE CONTENT. THE STORM PREDICTION CENTER HAS
THE MARGINAL RISK OVER THE NE PIEDMONT NE OF LYH...AND TO THE SOUTH
OF YADKINVILLE NC. HOWEVER...THINK THE EASTERN CWA WILL HAVE JUST
ENOUGH OF A THREAT TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK.
HIGHS TODAY WILL DEPEND ON CLOUD COVER...THINKING THE WEST WILL ONLY
GET INTO THE UPPER 70S TO MID 80S...WHILE THE ROANOKE VALLEY EAST TO
THE PIEDMONT HIT UPPER 80S...LOWER 90S. SOME HEAT INDICES COULD
REACH 100 FROM FARMVILLE TO DANVILLE IF MORE SUNSHINE OCCURS GIVEN
DEWPOINTS IN THE LOWER 70S.
TONIGHT...THE MODELS SHOW DRIER AIR OVERSPREADING OUR WESTERN CWA
WHILE THE FRONT EAST SLOWS DOWN AND KEEPS THE HIGHER DEWPOINTS
LINGERING LONGER. THE SHOWER/STORM THREAT WILL BE MOVING OUT OF THE
PIEDMONT BY MIDNIGHT...WITH SKIES CLEARING.
THE DEWPOINTS OVER THE MTNS WILL BE DROPPING INTO THE 50S BY DAWN
FRIDAY...AND YOU WILL BE ABLE TO TELL FRIDAY MORNING THAT THE
HUMIDITY IS LOWER. LOWS WILL RANGE FROM THE MID 50S DEEPER VALLEYS
OVER SE WV/FAR SW VA...TO AROUND 60 ELSEWHERE WEST OF THE BLUE
RIDGE...TO MID 60S FROM ROANOKE EAST TO THE PIEDMONT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
FORECAST MODELS AREA IN VERY GOOD AGREEMENT THAT THE WEATHER PATTERN
FOR THIS WEEKEND WILL BE DOMINATED BY A BROAD UPPER LEVEL TROUGH
EXTENDING SOUTHWARD FROM EASTERN CANADA...WHILE HIGH PRESSURE BUILDS
EASTWARD FROM THE CENTRAL PLAINS IN THE LOW LEVELS. THE HIGH WILL
BRING WITH IT DRIER AIR...PUSHING DEWPOINTS INTO THE 50S AND LOW
60S...WHICH WILL CUT DOWN ON THE HUMIDITY FOR THE WEEKEND.
EXPECT ABUNDANT SUNSHINE FOR FRIDAY WITH VERY LOW RAIN CHANCES IN A
LIGHT NORTH NORTHWESTERLY WINDFLOW.
A REINFORCING COLD FRONT WILL APPROACH FROM THE NORTH ON SATURDAY...
POSSIBLY BRINGING A FEW SHOWERS TO THE WESTERN RIDGES. CONSIDERING
LIMITED MOISTURE IN PLACE AHEAD OF THE APPROACHING FRONT...WILL
MAINTAIN LOW RAIN CHANCES FOR NOW.
WEAK HIGH PRESSURE WILL RETURN FOR SUNDAY...MAKING FOR MOSTLY CLEAR
SKIES...ALTHOUGH CANNOT RULE OUT A FEW POP UP SHOWERS DURING
AFTERNOON/EVENING.
AFTERNOON TEMPERATURES WILL RANGE FROM THE LOW 80S/A FEW UPPER 70S
ACROSS THE MOUNTAINS...TO THE UPPER 80S/LOW 90S ACROSS THE PIEDMONT
EACH DAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 50S/LOW 60S
WEST...TO THE LOW/MID 60S EAST. WITH COOL AIR DRAINAGE...MAY SEE A
FEW OF THE DEEPER MOUNTAIN VALLEYS FALL TO NEAR 50 DEGREES IN SPOTS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 1230 PM EDT WEDNESDAY...
PREDOMINATE UPPER TROFFINESS ACROSS THE MID ATLANTIC WILL KEEP NW FLOW
ALOFT IN PLACE FROM THE WEEKEND THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. THIS SHOULD INITIALLY KEEP OVERALL DRY WEATHER IN PLACE WITH
SURFACE HIGH PRESSURE BUILDING ACROSS THE REGION FROM THE NW SUNDAY-
MONDAY...AND TO THE SOUTH AHEAD OF A REINFORCING COLD FRONT BY
WEDNESDAY. ONLY EXCEPTION TO THIS COULD BE WITH MOISTURE BEING LIFTED
BACK INTO THE SE EARLY NEXT WEEK WITH LOW PRESSURE DEVELOPING ALONG THE
RESIDUAL FRONT NEAR THE COAST. HOWEVER THE EARLIER ECMWF AND CMC ABOUT
THE ONLY SOLUTIONS THAT STILL HINT AT THIS SO BASICALLY LEAVING OUT
MOST POPS OUTSIDE OF SOMETHING ISOLATED SE SECTIONS ON MONDAY.
COLUMN WILL GRADUALLY MOISTEN ENOUGH BY MIDWEEK TO POSSIBLY SUPPORT A
BIT MORE CONVECTION AS WEAK SHORTWAVES ALOFT TRAVERSE THE NW FLOW ON
TUESDAY AHEAD OF A STRONGER UPPER LOW AND COLD FRONT TO THE NORTH
WEDNESDAY. GUIDANCE REMAINS A BIT HESITANT TO PRODUCE MUCH IN THE WAY
OF PRECIP GIVEN MAIN LIFT TO THE NORTH BUT APPEARS ENOUGH FOCUS WITH
HEATING TO SUPPORT SOME LOW POPS TUESDAY AFTERNOON. BETTER CHANCES MAY
COME WEDNESDAY AS THE FRONT SAGS TOWARD THE AREA FROM THE NORTH AND
DEWPOINTS RISE BUT EVEN THEN SUPPORT THIS FAR SOUTH LACKING SO CHANCE
POPS IN ORDER. OTRW MAINLY A PERSISTENCE FORECAST WITH HIGHS 80S TO
AROUND 90 SE AND 60S OVERNIGHT EXCEPT SOME COOLER 50S VALLEYS EARLY IN
THE WEEK AS DEWPOINTS/HUMIDITY REMAIN LOW.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 140 PM EDT THURSDAY...
A COLD FRONT WILL CONTINUE TO MOVE EAST ACROSS THE REGION THIS
AFTERNOON INTO TONIGHT. MVFR SCT TO BKN CLOUDS WITH POCKETS OF
IFR/LIFR IN CONVECTION THIS AFTERNOON INTO THIS EVENING.
WINDS WILL BECOME NORTHWEST AT 5 TO 12 KTS THIS AFTERNOON...THEN
WEAKEN THIS EVENING INTO TONIGHT.
WITH DRIER AIR WORKING IN THE FOG THREAT SHOULD BE MINIMIZED...THOUGH
THERE IS A SMALL CHANCE THAT LWB/BCB COULD FOG IN GIVEN SOME
SLIGHTLY COOLER AIR OVER MOIST GROUND.
BEHIND THE FRONT...DRIER AIR UNDER VFR CONDITIONS EXPECTED
FRIDAY. NORTHWEST WINDS AT 5 TO 12 KTS EXPECTED FRIDAY AFTERNOON.
HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE
PERIOD.
EXTENDED AVIATION FORECAST...
UNDER HIGH PRESSURE...DRY AND VFR FRIDAY NIGHT THROUGH SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.EQUIPMENT...
OBSERVATIONS HAVE RETURN FOR LYNCHBURG VIRGINIA AIRPORT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...KK/WP
SHORT TERM...NF
LONG TERM...JH
AVIATION...KK/WP
EQUIPMENT...
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SYNOPSIS...
ISSUED AT 227 PM CDT THU JUL 30 2015
SEASONABLY WARM TEMPERATURES EXPECTED THROUGH THE WEEKEND.
THE MAIN BAND OF WESTERLIES IS CURRENTLY ACRS SRN CANADA AND THE
NRN CONUS...HAS LIMITED AMPLITUDE...AND HAS A RIDGE OVER THE W AND
A TROF OVER THE HUDSON BAY RGN. THE MAIN CHG DURING THE FCST
PERIOD WL BE A SLOW AND GRADUAL INCREASE IN AMPLITUDE...WITH THE
UPR TROF EXPANDING SWD. THAT WL TILT THE UPR FLOW INTO THE FCST
AREA MORE NWLY WITH TIME.
TEMPERATURES WILL START OUT WARM...WITH DAYTIME HIGHS THROUGH THE
WEEKEND 4-8F DEG ABV NORMAL. BY EARLY NEXT WK THE UPR FLOW SHOULD
TILT NW ENOUGH TO BRING COOLER AIR FM CANADA INTO THE RGN...LIKELY
DROPPING TEMPS TO A LITTLE BLO NORMAL BY LATE IN THE PERIOD. PCPN
CHCS WILL BE LIMITED SINCE THE VERY HUMID AIR WL REMAIN TO OUR
S...AND THE BEST DYNAMICS WITH THE UPR TROF WL STAY N. ALTHOUGH
ALL IT TAKES AT THIS TIME OF YEAR IS ONE CONVECTIVE EVENT TO
SUPPLY A NORMAL WEEKS WORTH OF PCPN...IT SEEMS LIKELY THAT MOST
AREAS WL END UP RECEIVING BLO NORMAL PCPN FOR THE PERIOD.
&&
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 227 PM CDT THU JUL 30 2015
MILD TEMPS AND DEWPOINTS IN THE LOWER 50S MADE FOR PLEASANT
CONDITIONS ACROSS NORTHEAST WISCONSIN LATE THIS AFTERNOON.
HOWEVER...19Z WATER VAPOR SHOWED A SHORTWAVE TRACKING THROUGH NE
MINNESOTA AND HEADING FOR NORTHERN WISCONSIN. THIS FEATURE HAS
ALREADY KICKED OFF SCATTERED STORMS THAT WERE MOVING THROUGH NW
WISCONSIN. WITH SOME INSTABILITY IN NORTH CENTRAL WISCONSIN...AND
LAPSE RATES OF 6-7K/KM...THESE STORMS SHOULD MAINTAIN THEMSELVES
THIS AFTERNOON AS THE SHORTWAVE SWINGS THROUGH. NOTHING SEVERE IS
EXPECTED AS CAPES ARE ONLY 500J/KG AT BEST...BUT WITH DRY AIR
ALOFT AND RAP SOUNDINGS SHOWING INVERTED-V-LIKE SIGNATURES...GUSTY
WINDS AND BRIEF HEAVY RAIN IS POSSIBLE THROUGH EARLY THIS EVENING
TO THE NORTH.
ANY LINGERING SHOWERS AND THUNDERSTORMS THIS EVENING SHOULD
QUICKLY DISSIPATE AFTER SUNSET. CLEAR SKIES SHOULD PREVAIL UNTIL
ABOUT MIDNIGHT AS A WEAK FRONT PUSHES THROUGH AND SCATTERED CLOUD
COVER DEVELOPS...WITH BROKEN CLOUDS TO THE NORTHAS BETTER QG
FORCING GIVES SOME ADDED LIFT.WITH VERY LITTLE CHANGE TO THE
OVERALL WEATHER PATTERN...STAYED CLOSE TO LAST NIGHTS LOW
TEMPERATURES WITH A HINT OF THE BEST PERFORMING GUIDANCE THROWN
IN.
FRIDAYS SET UP LOOKS A LOT SIMILAR TO WHAT WE HAD THIS AFTERNOON.
SUNNY AND DRY TO START THE DAY...WITH SOME FAIR WEATHER CU IN THE
AFTERNOON. ANOTHER WEAK SHORTWAVE WILL BE DROPPING THROUGH THE
MEAN FLOW WHICH COULD KICK OFF A FEW SHOWERS TO THE NORTH. WITH NE
WI SITTING ON THE ANTICYCLONIC SIDE OF A BROAD UPPER LEVEL...HAVE
DOUBTS SHOWERS WILL EVEN DEVELOP. FRIDAYS SHORTWAVE WILL NOT BE AS
DEFINED TODAYS WITH LITTLE TO NO ADDED INSTABILITY. HOWEVER
HIGH-RES MODELS CONTINUE TO SHOW ISOLATED PCPN DEVELOPING IN
RESPONSE TO THE LFQ OF A STRONG 300MB JETSTREAK BRUSHING NORTHERN
WISCONSIN. KEPT SLIGHT CHC POPS FRI AFTERNOON...THOUGH CONFINED
PCPN TO ONLY THE FAR NORTH. HIGHS TOMORROW WILL BE A DEGREE OR
TWO COOLER THAN TODAY...WITH CONTINUED BREEZY WEST WINDS THROUGH
NOT AS HIGH AS WE SAW TODAY.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 227 PM CDT THU JUL 30 2015
DAYTIME TEMPS WL CONT ABV NORMAL FOR A FEW DAYS...THEN EVENTUALLY
COOL AS THE UPR FLOW TILTS NWLY. STAYED CLOSE TO A BLEND OF THE
TOP PERFORMING GUIDANCE PRODUCTS.
HARD TO GET A HANDLE ON SPECIFICS OF THE PCPN FCST GIVEN THE
PATTERN. PCPN CHCS WL BE TIED TO SML SCALE SHRTWVS ROUNDING THE
BASE OF SLOWLY STRENGTHENING LNGWV TROF. CURRENT OP MODEL SUITE
NOT VERY ENCOURAGING FOR THE PCPN WE/VE BEEN CARRYING FOR SAT
NGT...WITH MANY OF THE MODELS NOW TAKING THAT THROUGH TO THE S OF
THE FCST AREA. LATE SUN/SUN NGT LOOK BETTER FOR PCPN AT THIS
POINT. BUT THEN AGAIN IN A PATTERN LIKE THIS...THINGS COULD LOOK
TOTALLY DIFFERENT TOMORROW. STUCK WITH CHC POPS FOR MOST AREAS FOR
SAT NGT...AND AGAIN ON SUN NGT.
NO SIG CHGS MADE TO THE EXTENDED FCST INITIALIZATION GRIDS BASED
ON A BROAD BLEND OF GUIDANCE PRODUCTS.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1125 AM CDT THU JUL 30 2015
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON ACROSS NORTHERN WISCONSIN IN RESPONSE TO A
SHORTWAVE SHIFTING THROUGH THE STATE. SOME OF THE PRECIP COULD
AFFECT RHI...HOWEVER COVERAGE SHOULD BE ISOLATED AND NOT ENOUGH
CONFIDENCE TO ADD TO TAF AT THIS TIME. WILL KEEP ON EYE ON HOW
THINGS DEVELOP AND WILL ADD IF COVERAGE IS GREATER AND FARTHER
SOUTH THAN ANTICIPATE CURRENTLY.
OTHERWISE...VFR CONDITIONS WILL CONTINUE ACROSS MUCH OF NE
WISCONSIN WITH GUSTY WEST WINDS. PCPN/CIGS/WINDS WILL DIMINISH
AFTER SUNSET...WITH ONLY A FEW CLOUDS POSSIBLY SWINGING THROUGH
TONIGHT MAINLY TO THE NORTH. FRIDAY SHOULD BE MORE OF THE SAME
WITH VFR CONDITIONS THROUGH MIDDAY. WEST WINDS WILL AGAIN
INCREASE THROUGH THE MORNING...BUT SHOULD NOT BE AS GUSTY AS
TODAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....ALLEN
LONG TERM......SKOWRONSKI
AVIATION.......ALLEN