Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/31/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
338 PM MST WED JUL 29 2015
.SYNOPSIS...SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED OVER
SOUTHERN ARIZONA AND SOUTHEAST CALIFORNIA TONIGHT...INCLUDING THE
LOWER DESERTS. LOCALIZED HEAVY RAIN AND STRONG WINDS CAN BE
EXPECTED...ESPECIALLY OVER HIGHER TERRAIN. HIGH PRESSURE BUILDING
OVER THE REGION WILL THEN GRADUALLY REDUCE RAIN CHANCES FROM THURSDAY
ONWARD INTO THE UPCOMING WEEKEND...AND INTO EARLY NEXT WEEK...BUT AT
LEAST SLIGHT CHANCES WILL REMAIN OVER SOUTH-CENTRAL ARIZONA.
TEMPERATURES WILL TAKE A SLIGHT DIP BELOW NORMAL THURSDAY DUE TO
WIDESPREAD CLOUD COVERAGE...BEFORE SLOWING WARMING BACK UP FROM
FRIDAY INTO EARLY NEXT WEEK AS THE ATMOSPHERE SLOWLY DRIES OUT.
&&
.DISCUSSION...
REST OF TODAY THROUGH THURSDAY...
STORM ACTIVITY BUILDING OVER GILA...SOUTHERN YAVAPAI...AND SOUTHEAST
ARIZONA ARE ANTICIPATED TO PRODUCE OUTFLOWS WHICH WILL LEAD TO NEW
STORM DEVELOPMENT OVER THE LOWER DESERTS. RELATIVELY HIGH POPS FOR
THIS EVENING ARE PREDICATED ON THAT. OF NOTE...MODEL CAPE NOT VERY
IMPRESSIVE FOR PHOENIX AREA AND LATEST HRRR UNIMPRESSIVE WITH
PRECIP/REFLECTIVITIES THERE AS WELL. MODEL CAPE IS BETTER OVER
SOUTHEAST CALIFORNIA...LESS SO SOUTHWEST ARIZONA. OF NOTE...HRRR
CONTINUES TO SHOW A GOOD DEAL OF ACTIVITY OVER LA PAZ COUNTY...DUE TO
INFLUENCE FROM SOUTHERN YAVAPAI STORMS. THE SHORT WAVE MOVING ACROSS
THE NORTHERN GULF OF CALIFORNIA AND SOUTHERN PORTIONS OF ARIZONA AND
CALIFORNIA HAS BEEN SLOW IN AIDING STORM PRODUCTION WHICH SUGGESTS
THAT DYNAMICAL FORCING HAS NOT BEEN OVERLY STRONG. THE MCV OVER
SOUTHERN ARIZONA HAS NOT BEEN PARTICULARLY PRODUCTIVE EITHER.
HOWEVER...WITH CLOUD COVER THINNING OUT AND A FEW HOURS OF DAYLIGHT
LEFT...THE WINDOW OF OPPORTUNITY HAS NOT CLOSED YET. THE STRONGER
STORMS WILL BE CAPABLE OF LOCALIZED FLOODING AS WELL AS STRONG
ERRATIC WINDS.
THURSDAY MAY START OFF LOOKING LIKE TODAY WITH A LOT OF DEBRIS CLOUDS
AND SPOTTY SHOWERS AROUND AS MODELS INDICATE AN MCV ORIGINATING FROM
SONORA MOVING THROUGH VERY LATE TONIGHT AND THURSDAY MORNING. LATEST
SREF ACTUALLY DEPICTS MORE CAPE THURSDAY THAN TODAY. IF WE ARE ACTIVE
TONIGHT...THAT WONT BE THE CASE. CONVERSELY...IF WE STAY RELATIVELY
QUIET THEN THAT COULD VERY WELL BE THE CASE. AS USUAL THIS TIME OF
YEAR...A LOT OF UNCERTAINTY REMAINS.
FRIDAY AND BEYOND...ALTHOUGH THERE WILL STILL BE ENOUGH MONSOON
MOISTURE TO KEEP UP SOME ACTIVITY DURING THIS PERIOD...A GRADUAL
DOWNTREND IN CONVECTIVE ACTIVITY AND A SLOW WARMING TREND APPEARS TO
BE IN THE CARDS AS THE MAIN UPPER HIGH CENTER GRADUALLY BUILDS
OVERHEAD AND THE ATMOSPHERE SLOWLY DRIES OUT...WITH PWATS FALLING
INTO THE 1.30 TO 1.50 RANGE BY EARLY NEXT WEEK.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
STORMS OVER GILA AND SOUTHERN YAVAPAI COUNTIES...AS WELL AS SOUTHEAST
ARIZONA...ARE EXPECTED TO PRODUCE OUTFLOW WINDS WHICH WILL EVENTUALLY
GENERATE NEW STORMS OVER THE VALLEY FLOOR...MAINLY AFTER 00Z. ENOUGH
UNCERTAINTY REMAINS THAT VICINITY THUNDERSTORM PHRASING WAS USED IN
THE TAFS AS OPPOSED TO TEMPO OR PREVAILING TSRA. ENOUGH MOISTURE IS
AVAILABLE IN THE ATMOSPHERE THAT STORMS WILL BE CAPABLE OF PRODUCING
LOCALLY REDUCED VISIBILITY IN HEAVY RAIN. IF STRONG STORMS MANAGE TO
FORM OVER PINAL COUNTY...THEN LARGE AREAS OF DUST ARE POSSIBLE BUT
PROBABLY ANY BLOWING DUST WILL TEND TO BE PATCHY. LINGERING DEBRIS
CLOUDS AND SHOWERS ARE QUITE POSSIBLE THROUGH THE OVERNIGHT HOURS.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP BY 01Z WITH MOST OF
THE ACTIVITY FINISHED BY 07Z. HOWEVER...LINGERING DEBRIS SHOWERS AND
CLOUDS POSSIBLE OVERNIGHT. ENOUGH UNCERTAINTY REMAINS AT ANY GIVEN
TAF SITE THAT VICINITY THUNDERSTORM PHRASING WAS USED AS OPPOSED TO
TEMPO OR PREVAILING TSRA. ENOUGH MOISTURE IS AVAILABLE IN THE
ATMOSPHERE THAT STORMS WILL BE CAPABLE OF PRODUCING LOCALLY REDUCED
VISIBILITY IN HEAVY RAIN ALONG WITH STRONG WINDS. IF STRONG ENOUGH STORMS
MANAGE TO FORM...THEN LARGE AREAS OF DUST ARE POSSIBLE BUT PROBABLY
ANY BLOWING DUST WILL TEND TO BE PATCHY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...SATURDAY THROUGH WEDNESDAY...ATMOSPHERIC MOISTURE
WILL DECLINE FROM WEST TO EAST OVER THE WEEKEND. THIS WILL CONFINE
STORM CHANCES TO SOUTH-CENTRAL ARIZONA...MAINLY THE HIGHER
TERRAIN...THROUGH THE FIRST HALF OF NEXT WEEK. HUMIDITIES WILL BE A
BIT LOWER AS WELL WITH MAX TEMPERATURES A BIT ABOVE NORMAL. 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/PERCHA
AVIATION...AJ
FIRE WEATHER...AJ
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
958 AM MDT WED JUL 29 2015
.UPDATE...
ISSUED AT 958 AM MDT WED JUL 29 2015
SCATTERED RAIN SHOWERS HAVE DEVELOPED OVER LINCOLN COUNTY ON THE
NORTHERN FRINGE OF THE MONSOONAL MOISTURE MOVING OVER THE STATE
OUT OF NEW MEXICO. THE HRRR MODEL MOVES THESE SHOWERS OFF TO THE
EAST OVER THE NEXT COUPLE HOURS WITH DRY WEATHER THEN CONTINUING
THROUGH THE AFTERNOON ACROSS THE FORECAST AREA. THE LATEST RUN OF
THE NAM ALSO SHOWS THE FORECAST AREA REMAINING DRY THIS AFTENROON
AND EVENING AFTER THE THE LINCOLN COUNTY SHOWERS DISSIPATE.
CURRENT FORECAST FOR THIS AFTERNOON SHOWS LOW POPS OVER PARK
COUNTY AND THE PALMER DIVIDE...WHICH WILL REMAIN UNCHANGED TO
ACCOUNT FOR THE PRESENCE OF MOISTURE TO OUR SOUTH.
ADDING A COUPLE HOURS OF SCATTERED SHOWERS TO THE PALMER DIVIDE
THIS MORNING WILL BE THE ONLY CHANGE TO THE FORECASTS AT THIS
TIME.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 349 AM MDT WED JUL 29 2015
A WEST-SOUTHWEST FLOW ALOFT WILL PREVAIL AS AN UPPER LEVEL RIDGE
REMAINS OVER THE SOUTHERN PLAINS. A FEW SHOWERS HAVE FORMED THIS
MORNING OVER LINCOLN COUNTY AND ARE EXPECTED TO MOVE EAST OF THE
AREA. MONSOON MOISTURE WILL REMAIN OVER THE STATE...WITH THE
GREATEST MOISTURE BEING OVER THE SOUTHEAST COLORADO. PRECIPITABLE
WATER VALUES WILL BE THREE-QUARTERS OF AN INCH TO ONE INCH.
HOWEVER...AIRMASS WILL BE STABLE OVER THE PLAINS AND SLIGHTLY
UNSTABLE ALONG THE FRONT RANGE AND OVER THE HIGHER TERRAIN WHERE
CAPES WILL BE LESS THAN 500 J/KG. BEST CHANCE FOR A SHOWER OR STORM
WILL BE SOUTH AND OVER THE HIGHER TERRAIN THIS AFTERNOON AND
EVENING.
SURFACE HIGH WILL MOVE FROM THE NORTHERN ROCKIES TO CENTRAL PLAINS.
THIS WILL PRODUCE SOUTHEAST WINDS TO WITH GUSTS THIS AFTERNOON UP TO
25 MPH. HIGHS TODAY WILL BE SIMILAR TO YESTERDAY`S READINGS WITH
HIGHS IN THE 80S OVER NORTHEAST COLORADO.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 349 AM MDT WED JUL 29 2015
ON THURSDAY...A BROAD UPPER LEVEL RIDGE WILL STRETCH FROM SRN
CALIFORNIA TO THE SERN GULF STATES AND ALONG ITS NORTHERN PERIPHERY
60-80KT MID-LEVEL ZONAL FLOW. BENEATH THE WRN SECTOR OF THIS RIDGE
WILL BE A PLUME OF SUBTROPICAL MOISTURE WHICH MODELS SHOW NUDGING
NORTHWARD OVER SRN COLORADO. FROM THERE THEY SHOW THE MAIN CORE OF
THIS MOISTURE BEING SHEARED EASTWARD AWAY FROM NERN COLORADO AND THE
FRONT RANGE. HOWEVER LATE ON THURSDAY...MODELS ALSO SHOW SELY SFC-
700MB ON THE PLAINS OF COLORADO DRIVING A LOW-LEVEL MOISTURE/THETA-E
RIDGE UP INTO NERN COLORADO. BY THURSDAY EVENING...NAM INDICATES 750-
1000 J/KG OF SFC BASED CAPE ACROSS DOUGLAS...ELBERT AND LINCOLN
COUNTIES. GFS AND ECMWF CAPES ARE SPREAD OUT ACROSS THE PLAINS WITH
THE HIGHER VALUES APPROACHING A 1000 J/KGS ACROSS THE SERN CORNER OF
THE CWA. IF IT WERE NOT FOR THE WARM TEMPERATURES ALOFT AND STG CAP
UP AROUND 550 MBS...ERN SECTIONS OF THE FCST AREA COULD END UP
SEEING MORE THAN JUST A FEW LOW TOP T-STORMS PRODUCING NO MORE THAN
A RAIN SHOWER AND GUSTY WINDS. THAT SAID...HAVE SLIGHTLY RAISED
PRECIP CHANCES OVER THE FRONT RANGE AND ALONG THE PALMER DIVIDE OUT
ACRS LINCOLN COUNTY THURSDAY AFTERNOON AND EVENING. AREAS ROUGHLY
NORTH OF DENVER SHOULD ESCAPE ANY PRECIP OR STORMS AS THIS AIR
APPEARS DRIER AND TOO CAPPED. HIGHS ON THURSDAY ONLY SLIGHTLY WARMER
THAN WEDNESDAY AND SLIGHT A 1-2DEGS C BELOW AVERAGE FOR THE DATE.
FOR FRIDAY...THE UPPER RIDGE IS FORECAST TO BUILD NORTHWESTWARD UP
OVER THE GREAT BASIN PLACING NERN COLORADO MORE UNDER NWLY FLOW
ALOFT. THIS LEADS TO DRYING ALOFT BUT NOT MUCH IN THE WAY OF
COOLING. THIS AMPLIFICATION ON THE RIDGE ALLOWS FOR SOME SUBTROPICAL
MOISTURE POOLING OVER NEW MEXICO/ERN ARIZONA TO FLOW NORTHWARD ALONG
THE SPINE OF THE COLORADO ROCKIES. PW CHARTS SHOW HIGH COUNTRY
VALUES CREEPING UP THROUGH THE DAY WITH THE NAM AND GFS INDICATING
POCKETS OF LIGHT QPF OVER AND NEAR THE FRONT RANGE BY AFTERNOON.
HOWEVER THE EC AND SREF SHOW THE BULK OF THIS LIGHT PRECIP FARTHER
OUT ON THE PLAINS IN PROXIMITY OF GREATER LOW-LEVEL MOISTURE...
ELEVATED CAPE AND SHEAR VALUES. FOR NOW WILL HOLD ONTO 20-30PCT POPS
OVER THE HIGH TERRAIN...AND 10-20PCT POPS MAINLY OVER THE PALMER
DIVIDE AND ADJACENT PLAINS THRU EVENING ON FRIDAY.
LOOKING AHEAD TO THE PERIOD SATURDAY-WEDNESDAY...THE UPPER RIDGE
CONTINUES TO BULGE NORTHWESTWARD TOWARDS THE PACIFIC NORTHWEST OVER
THE WEEKEND...PLACING THE FCST AREA UNDER A DRIER AND MORE STABLE
NORTHWESTERLY MID-LEVEL FLOW. THEREFORE SHOULD SEE LESS STORM
ACTIVITY ON SATURDAY...WITH THE BETTER CHANCE OF T-STORMS WITH
STEEPER LAPSE RATES OVER THE HIGHER TERRAIN. ON SUNDAY...MODELS SHOW
THE UPPER RIDGE SHIFTING EAST WITH LIGHT W-NWLY FLOW OVER THE CWA.
SUBTROPICAL MOISTURE TRAPPED BENEATH THE RIDGE COUPLED WITH STG
DAYTIME HEATING MAY RESULT IN A BIT MORE T-STORM COVERAGE IN THE
HIGH COUNTRY. SO RAISED POPS SLIGHTLY UP THERE. DO NOT SEE MUCH
CONVECTIVE ACTIVITY ON THE PLAINS. HIGHS ON SATURDAY AND SUNDAY
CONTINUE TO CREEP UP WITH READING RETURNING TO NEAR TO SLIGHTLY
ABOVE AVERAGE. MONDAY THROUGH WEDNESDAY...THE UPPER RIDGE IS PROGGED
TO REMAIN OVER THE ROCKY MTN REGION WITH LITTLE DAY-TO-DAY CHANGE IN
WEATHER. EXPECT NEAR AVERAGE TEMPS AND A SLIGHT CHANCE OF AFTERNOON
AND EVENING T-STORMS MTNS AND PLAINS EACH DAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z THURSDAY MORNING)
ISSUED AT 958 AM MDT WED JUL 29 2015
MANAGING WIND SHIFTS AT THE AIRPORT THROUGH THIS AFTERNOON WILL BE
THE ONLY FORECAST PROBLEM OF THE DAY TODAY. SOUTHEASTERLY FLOW
ACROSS THE PLAINS IS FORECAST TO PERSIST THROUGH THE AFTERNOON
WHICH WILL PRODUCE SOUTH TO SOUTHEASTERLY WINDS AT KDEN THROUGH
THIS EVENING. THE TRANSISTION BACK TO NOCTURNAL SOUTHERLIES SHOULD
THEN OCCUR BETWEEN 02Z AND 04Z. NO OTHER AVIATION IMPACTS TODAY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DANKERS
SHORT TERM...MEIER
LONG TERM...BAKER
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1125 PM MDT TUE JUL 28 2015
.UPDATE...
ISSUED AT 1115 PM MDT TUE JUL 28 2015
VERY LITTLE IN THE WAY OF CONVECTION HAS OCCURRED THIS EVENING
OVER THE AREA...DESPITE MOST MODELS...INCLUDING NEWLY ARRIVING 00Z
RUNS...INSISTING ON -SHRA/-TSRA ALONG AND EAST OF THE MOUNTAINS
THROUGH THE NIGHT. LATEST 03Z/04Z RUNS OF THE HRRR HAVE FINALLY
CAUGHT ON TO THE DRY TREND...WITH JUST SOME VERY ISOLATED SHOWERS
ACROSS THE EASTERN MOUNTAINS AND PLAINS THROUGH THE NIGHT...BEST
CHANCES OVER BACA COUNTY AS DEEPER CONVECTION STAYS FAIRLY CLOSE
TO THE SE CORNER OF THE STATE. WILL DROP THE MENTION OF THUNDER
FROM MANY ZONES FOR THE REMAINDER OF THE NIGHT...BUT KEEP A
MENTION OF SOME ISOLATED -SHRA OVER THE ERN MTS/PLAINS AS WEAK
WARM ADVECTIVE LIFT MAY FINALLY PRODUCE SOME LIGHTER PRECIP AFTER
MIDNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 259 PM MDT TUE JUL 28 2015
...COOLER WITH INCREASED CHANCES OF STORMS...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS CONTINUES TO
INDICATE MODERATE WEST TO SOUTHWEST FLOW ALOFT ACROSS THE STATE WITH
A BROAD UPPER HIGH ACROSS THE SOUTHERN HIGH PLAINS BUILDING INTO THE
SOUTHERN ROCKIES AS STRONG UPPER TROUGH CONTINUES TO TRANSLATE EAST
ACROSS THE UPPER MIDWEST AND NORTHERN HIGH PLAINS. WATER VAPOR
IMAGERY CONTINUES TO INDICATE MONSOONAL MOISTURE PLUME ACROSS THE
DESERT SW AND SOUTHERN ROCKIES STREAMING ACROSS SOUTHERN COLORADO
AND INTO WESTERN KANSAS AT THIS TIME.
AT THE SFC...THIS MORNINGS PASSING COLD FRONT HAS MOVED INTO EAST
CENTRAL NEW MEXICO AND THE WESTERN TEXAS PANHANDLE...WITH BREEZY
EAST TO SOUTHEAST WINDS ACROSS THE EASTERN PLAINS KEEPING
TEMPERATURES SOME 10 DEGREES COOLER THAN THIS SAME TIME YESTERDAY.
FURTHER WEST...TEMPS ARE RUNNING SIMILAR TO YESTERDAY. REGIONAL
RADARS ONLY INDICATING A FEW ECHOES ACROSS THE SOUTHERN MTS WITH A
BETTER COVERAGE OF STORMS ACROSS NORTH CENTRAL AND NORTHEAST NEW
MEXICO.
TONIGHT AND WEDNESDAY...FLOW ALOFT SLOWLY BECOMES MORE WESTERLY AS
UPPER MIDWEST SYSTEM CONTINUES TO MOVE EAST AND UPPER HIGH CONTINUES
TO BUILD WEST INTO THE SOUTHERN ROCKIES...OWNING TO A SLIGHT
INCREASE IN MONSOONAL MOISTURE ACROSS THE AREA THROUGH THE DAY
TOMORROW. MODELS CONTINUE TO INDICATE CONVECTION ACROSS NORTH
CENTRAL NEW MEXICO TO CONTINUE TO LIFT NORTHEAST AND DEVELOPING INTO
AN MCS ROLLING ACROSS THE SOUTHEAST COLORADO AND NEW MEXICO BORDER
LATE TONIGHT AND INTO EARLY WEDNESDAY MORNING AND HAVE KEPT THE BEST
POPS ACROSS THIS AREA. ACROSS THE REST OF THE AREA...HAVE KEPT
ISOLATED POPS THROUGH THE EARLY EVENING. MODEL SOUNDINGS INDICATING
INCREASING MOISTURE WITHIN THE LOW LEVEL UPSLOPE ACROSS THE EASTERN
PLAINS...ALONG WITH DEVELOPING MID LEVEL WAA...TO SUPPORT ELEVATED
CONVECTION AND POSSIBLE SHOWERS AND A FEW STORMS ACROSS THE EASTERN
MTS AND ADJACENT PLAINS LATER THIS EVENING AND OVERNIGHT.
THE INCREASED AVAILABLE MOISTURE ACROSS THE AREA TOMORROW SHOULD
LEAD TO BETTER COVERAGE OF STORMS OVER ALL OF THE HIGHER TERRAIN
WITH STORMS SPREADING EAST ACROSS THE ADJACENT PLAINS THROUGH THE
AFTERNOON. THE BEST COVERAGE OF STORMS REMAINS ACROSS THE SOUTHERN
MTS AND ADJACENT PLAINS...WITH THE PROXIMITY TO THE MONSOONAL PLUME.
HIGH TEMPERATURES ARE EXPECTED TO BE NEAR TO WELL BELOW SEASONAL
AVERAGES...COOLEST ACROSS THE EASTERN PLAINS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 259 PM MDT TUE JUL 28 2015
LATEST MODEL RUNS SHOW SOUTHERLY TAP OF MONSOON MOISTURE WILL REMAIN
ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA THROUGH FRIDAY WHILE
AT THE SURFACE LOW LEVEL SOUTHEAST FLOW WILL ADVECT 50 AND LOWER 60
DEW POINTS BACK INTO SOUTHEAST CO. WEAK DISTURBANCES ROTATING
NORTHWARD OUT OF NEW MEXICO WILL GET SHUNTED EASTWARD ACROSS
SOUTHERN SECTIONS OF THE FORECAST AREA PROVIDING FORCING FOR
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS THROUGH
THURSDAY...WITH MAJORITY OF THE ACTIVITY EXPECTED DURING THE
AFTERNOON AND EVENING HOURS. HOWEVER SEVERAL OF THE SHORT AND
MEDIUM RANGE MODELS SUGGEST ACTIVITY MAY PERSIST WED NIGHT NORTH
OF THE STALLED FRONTAL BOUNDARY ACROSS EAST CENTRAL NM/TX
PANHANDLE WHICH MAY AFFECT SOUTHERN PORTIONS OF THE SOUTHEAST
PLAINS. THERE IS SUFFICIENT AGREEMENT IN THE MODELS TO KEEP AT
LEAST SOME ISOLATED TO LOW END SCATTERED POPS ACROSS THE RATON
RIDGE AND FAR SOUTHEAST CORNER WED NIGHT THROUGH THURS
MORNING...BUT HUNCH IS MORE WIDESPREAD ACTIVITY BE FARTHER SOUTH
IN CLOSER PROXIMITY TO THE FRONTAL BOUNDARY.
THURSDAY...THE UPPER HIGH BUILDS ACROSS THE GREAT BASIN AND WESTERN
US...WHICH PUTS CO UNDER A MORE NW FLOW COMPONENT ALOFT. STILL
PLENTY OF MOISTURE AVAILABLE WITH DEW POINTS REMAINING IN THE 50S
AND LOWER 60S ACROSS EASTERN SECTIONS OF THE DISTRICT...WITH 40S ACROSS
THE SOUTHWEST MTS/SAN LUIS VALLEY. BUT RISING HEIGHTS ALOFT
REALLY CUTS BACK ON CAPE VALUES...AND APPEARS TRAJECTORY FOR ANY
WEAK DISTURBANCES EMBEDDED WITHIN THE MONSOON PLUME MAY SHIFT OFF
TO THE WEST...ACROSS AZ/NM. SO THURS LOOKS LIKE ANOTHER DAY OF
NEAR TO SLIGHTLY BELOW CLIMO TEMPERATURES...WITH GREATEST POPS
ACROSS THE SE MTS...AND SRN SECTIONS OF THE DISTRICT. LOCALLY
HEAVY RAINFALL WILL BE THE PRIMARY STORM THREAT...AS SHEAR LOOKS
TOO WEAK TO SUPPORT MUCH OF A SEVERE THREAT.
FRIDAY LOOKS A TAD MORE ACTIVE NOW FOR THE SOUTHWEST MOUNTAINS AS
ANOTHER DISTURBANCE ENTERS THE 4 CORNERS REGION DURING THE
AFTERNOON. AGAIN...0-6KM SHEAR VALUES LOOK RELATIVELY WEAK...AND
CAPE REMAINS BELOW 1000 J/KG...SO MAIN THREAT WITH THUNDERSTORMS
WILL BE LOCALLY HEAVY RAINFALL.
DRIER AND WARMER WEATHER IS EXPECTED FOR THE WEEKEND AS NORTHWEST
FLOW ALOFT ADVECTS DRIER AIR INTO THE REGION ALOFT. SFC DEW POINTS
START TO FALL OFF WITH AFTERNOON MIXING ACROSS THE I-25
CORRIDOR...AND MOST THUNDERSTORMS SHOULD STAY CONFINED TO THE
MOUNTAIN AREAS. EVENTUALLY ANOTHER UPSWING IN THUNDERSTORM
CHANCES MAY SPREAD INTO WESTERN CO BY EARLY NEXT WEEK AS MONSOON
MOISTURE ENTRAINED WITHIN THE UPPER HIGH SPREADS IN FROM THE WEST.
GFS SUGGESTS ANOTHER FRONT MAY DROP THROUGH THE PLAINS FOR
TUESDAY...INCREASING POPS FOR THE EASTERN SECTIONS AS WELL. ECMWF
LOOKS A TOUCH SLOWER THAN GFS...BUT WILL START TO TREND DOWN MAX
TEMPS A FEW DEGREES FOR NEXT TUES. -KT
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1115 PM MDT TUE JUL 28 2015
HAVE DROPPED THE MENTION OF -SHRA OVERNIGHT FROM ALL TAF SITES AS
PRECIP HAS BEEN VERY SLOW TO DEVELOP. MAY SEE SOME LIGHT PRECIP
OVER THE PLAINS TOWARD 12Z AS WEAK WARM ADVECTION CONTINUES...BUT
COVERAGE LOOKS TOO LOW TO INCLUDE IN TAFS. ON WED...VFR THROUGH
THE MORNING WITH TSRA DEVELOPING OVER THE MOUNTAINS BEGINNING 18Z.
MOISTURE LEVELS AND INSTABILITY LOOK HIGHER WED
AFTERNOON/EVENING...AND EXPECT GREATER COVERAGE OF
STORMS...ESPECIALLY ALONG AND WEST OF I-25. WILL INCLUDE A VCTS
MENTION ALL TAFS FROM ABOUT 19Z-21Z THROUGH 02Z-03Z...AND EXPECT
MOST STORMS TO PRODUCE AT LEAST A BRIEF PERIOD OF MVFR CIGS/VIS
DUE TO HEAVY RAINFALL.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...PETERSEN
SHORT TERM...MW
LONG TERM...KT
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS MIAMI FL
838 PM EDT THU JUL 30 2015
.UPDATE...
ONLY ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED THROUGH THE
NIGHT ACROSS MAINLY THE LAKE OKEECHOBEE REGION AND REGIONAL WATERS
WITH STRONGER RIDGING TO THE SOUTH. HRRR CONTINUES TO DOWNPLAY
POPS THROUGH THE REMAINDER OF THE NIGHT WITH EACH SUCCESSIVE
SOLUTION. UPDATED FORECAST BASED ON LATEST TRENDING. UPDATE SENT.
&&
.PREV DISCUSSION... /ISSUED 814 PM EDT THU JUL 30 2015/
AVIATION...
VFR CONDITIONS TO PREVAIL AT ALL SITES THROUGH THE PERIOD OUTSIDE
OF ANY AFTERNOON CONVECTION. PREVAILING FLOW WILL CONTINUE TO BE
SOUTHWESTERLY WITH AN EAST COAST SEA BREEZE BY FRIDAY AFTERNOON.
THIS SHOULD ALLOW ENOUGH CONVERGENCE TO FACILITATE SHOWERS AND
THUNDERSTORMS FOCUSED MAINLY ACROSS THE INTERIOR AND ATLANTIC
COAST FRIDAY AFTERNOON.
PREV DISCUSSION... /ISSUED 434 PM EDT THU JUL 30 2015/
DISCUSSION...
A COMPLEX SYNOPTIC ENVIRONMENT IS DEVELOPING ACROSS THE
SOUTHEASTERN STATES AND ACROSS NORTHERN FLORIDA. A COLD FRONT
APPROACHING THE ATLANTIC SEA BOARD EXTENDS ACROSS THE
SOUTHEASTERN STATES WITH A SURFACE TROUGH IN THE NORTHEASTERN
GULF AND AN AREA OF LOW PRESSURE OFF THE CAROLINAS COAST. IN THE
UPPER LEVELS THERE IS A CUTOFF LOW TO THE EAST OF THE BAHAMAS WITH
A WEAK MID LEVEL TROUGH JUST EAST OF THE FLORIDA PENINSULA. ALL OF
THESE FEATURES ARE MAINTAINING DEEP TROPICAL MOISTURE AND
EXTENSIVE CLOUDINESS ACROSS THE CENTRAL AND NORTHERN GULF AND TO
THE EAST OF CENTRAL AND SOUTH FLORIDA.
RECENT SATELLITE IMAGERY INDICATES THE LOW OFF THE CAROLINAS COAST
IS SHOWING AN EXPOSED AND WEAK LOW LEVEL CIRCULATION. THE RECENT
GUIDANCE INDICATES THAT THIS LOW IS FORECAST TO DRIFT NORTHWARD
AND BEGIN TO MERGE WITH THE COLD FRONT THAT IS FORECAST TO MOVE
OFF THE NORTH CAROLINA COAST ON FRIDAY. THE BROAD AREA OF LOW
PRESSURE ACROSS THE NORTHEASTERN GULF IS FORECAST TO SPREAD INTO
THE CENTRAL AND WESTERN GULF ON FRIDAY
FOR FRIDAY...AS THE SURFACE TROUGH IN THE GULF CONTINUES TO SINK
SOUTHWARD INTO THE CENTRAL GULF THE LOW LEVEL SOUTHWESTERLY FLOW
WILL BRING IN DEEP TROPICAL MOISTURE INTO SOUTH FLORIDA WITH THE
FORECAST PWAT AROUND 1.9 INCHES. IN ADDITION THE FORECAST
SOUNDINGS INDICATE COOLER MID LEVEL TEMPERATURES AND STEEPENING
LAPSE RATES WITH THE STABILITY INDICES INDICATING INCREASED
POTENTIAL FOR CONVECTION. SCATTERED TO NUMEROUS AFTERNOON
SHOWERS/THUNDERSTORMS ARE EXPECTED ACROSS THE PENINSULA WITH
SCATTERED ACTIVITY ACROSS THE LOCAL GULF AND ATLANTIC
WATERS. SOUTH TO SOUTHWESTERLY SURFACE WINDS WILL FAVOR THE
GREATEST COVERAGE OF SHOWERS AND THUNDERSTORMS ACROSS THE EASTERN
PENINSULA WITH NUMEROUS SHOWERS/THUNDERSTORMS FORECAST ACROSS THE
LAKE REGION AND PALM BEACH COUNTY.
FOR THE WEEKEND...THE CLOSED UPPER LEVEL LOW IS FORECAST TO
RETROGRADE SLOWLY WESTWARD INTO THE WEEKEND. THE TROUGH ACROSS
THE NORTHERN AND WESTERN GULF IS FORECAST TO LINGER INTO SATURDAY
BUT START TO LIFT NORTHWARD BY SUNDAY WITH HIGH PRESSURE FORECAST
TO BUILD BACK INTO THE REGION ON SUNDAY WITH SOUTHEASTERLY SURFACE
WINDS. WEATHER WISE...DEEP MOISTURE WILL LINGER OVER THE WEEKEND
WITH REGIONAL PWAT`S AROUND 1.9 INCHES. THE MOST ACTIVE PERIOD OF
SHOWERS/THUNDERSTORMS IS FORECAST ON SATURDAY WITH COOLER MID
LEVEL TEMPERATURES AND FORECAST SOUNDINGS INDICATING A LOCALLY
UNSTABLE ATMOSPHERE. THE GREATEST COVERAGE OF CONVECTION IS
FORECAST ACROSS THE NORTHERN HALF OF THE PENINSULA. BY SUNDAY
WITH THE SURFACE RIDGE RETURNING AND WARMER MID LEVEL
TEMPERATURES...SCATTERED ACTIVITY IS FORECAST BUT THE COVERAGE
WILL BE LESS THAN SATURDAY ACROSS THE REGION.
FOR THE LONG TERM FORECAST...HIGH PRESSURE AND SOUTHEASTERLY
WINDS WILL CONTINUE INTO THE EARLY PART OF NEXT WEEK BUT
LINGERING MOISTURE WILL ALLOW FOR AFTERNOON SHOWERS/THUNDERSTORMS
TO CONTINUE ACROSS THE PENINSULA.
MARINE...
SOUTHERLY TO SOUTHWESTERLY WINDS WILL LINGER ACROSS THE REGIONAL
WATERS TONIGHT INTO FRIDAY. A TRANSITION TO SOUTHEASTERLY WINDS
IS EXPECTED OVER THE WEEKEND. REGIONAL WINDS ARE FORECAST TO BE IN
THE 10 TO 15 KNOT RANGE OR LESS LATE THIS WEEK THROUGH THE
WEEKEND WITH GULF AND ATLANTIC SEAS MAINLY IN THE 1 TO 2 FOOT
RANGE THROUGH THIS PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 75 89 77 89 / 20 60 50 60
FORT LAUDERDALE 78 90 80 89 / 20 50 30 50
MIAMI 78 91 79 90 / 20 50 30 40
NAPLES 78 88 77 90 / 30 50 30 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
9 AM EDT WED JUL 29 2015
.DISCUSSION... PER THE 29/12Z SOUNDINGS THE 500MB TROUGH AXIS LOOKS
TO HAVE PUSHED SOUTH TO THE LAKE OKEECHOBEE AREA. THE 12Z/8AM BUOY
REPORTS INDICATE THAT THE SURFACE TROUGH AXIS WAS STILL LAGGING BACK
TO AROUND THE CAPE CANAVERAL AREA. WATER VAPOR LOOP SHOWS RELATIVELY
DRIER MID/UPPER LEVEL AIR MASS TRYING TO WORK ITS WAY ACROSS NORTH
FLORIDA AND TOWARD CENTRAL FLORIDA. THE 12Z SOUNDINGS INDICATE
PRECIPITABLE WATER VALUES STILL HIGH AND RANGE FROM 1.95 AT
TALLAHASSEE TO 2.26 AT CAPE CANAVERAL. RAIN CHANCES TO REMAIN HIGH
RANGING FROM AROUND 50 PERCENT NORTH TO 30 PERCENT SOUTH. MODELS
BOTH LONGER TERM/GFS AND SHORT TERM MODELS SUCH AS THE HRRR AND
LOCAL WRF/S INDICATE THAT THE LOW OFF THE FLORIDA EAST COAST WILL
CONTINUE TO TRACK AWAY FROM FLORIDA. THE WINDS SHOULD SHIFT TO THE
NORTHWEST THROUGH NORTHEAST DURING THE DAY. PARTLY CLOUDY SKIES
NORTH AND WINDS SPEEDS LOOK LIGHT ENOUGH TO ALLOW FOR AFTERNOON SEA
BREEZES.
.AVIATION...SCATTERED TEMPO MVFR CONDITIONS DUE TO LOW CLOUDS AND
MIST/FOG UNTIL 29/1400Z. WARM TEMPERATURES ALOFT HOLD DOWN
THUNDERSTORMS PROBABILITY SO WILL KEEP VCTS FOR THE AFTERNOON.
.MARINE...BUOYS RECORDING SOUTHWEST WINDS 5 TO 10 KNOTS AT THE COAST
AND NEARSHORE...AND 15 TO 20 KNOTS AT BUOY 010 AT 12NM OFFSHORE. THE
OUTLIER WAS THE CMAN AT SAINT AUGUSTINE WHERE THE WIND WAS NORTHWEST
AT 5 TO 10 KNOTS.
WINDS FORECAST TO SHIFT TO THE NORTHWEST AND NORTH DURING THE DAY AS
LOW PRESSURE OFF NORTHEAST AND CENTRAL FLORIDA TRACKS EAST INTO THE
ATLANTIC. WINDS LOOK LIGHT ENOUGH TO ALLOW FOR AN ONSHORE WIND
DOWN TO AT LEAST SEBASTIAN INLET IN THE AFTERNOON.
PREVIOUS AFD
TODAY-TONIGHT...LOCAL WEATHER PATTERN CONTINUES TO BE DRIVEN BY THE
DIFFUSE LOW LEVEL BOUNDARY MEANDERING ACROSS THE NORTH/CENTRAL
PENINSULA. LATEST SURFACE ANALYSIS SHOWS A BROAD AND WEAK SURFACE
LOW OVER NE FLORIDA AND ADJACENT ATLANTIC WITH THE LOW LEVEL
BOUNDARY MARKED BY A SLIGHT WIND SHIFT SOMEWHERE IN NORTH FLORIDA/S
GEORGIA.
MODELS SHOW SURFACE LOW CONSOLIDATING OF TO OUR NE OVER THE NEXT 24
HOURS (THOUGH WITH LITTLE IN THE WAY OF DEEPENING)...WHICH WILL BE
ENOUGH TO DRIVE THE BOUNDARY A LITTLE FURTHER SOUTH AND MORE
SOLIDLY BACK INTO CENTRAL FLORIDA. THIS OCCURS WHILE THE UPPER
LEVEL TROUGH AXIS ALSO SHIFTS MORE SOUTHEAST THIS AFTERNOON.
THE NET RESULT IS THAT THE NARROWING DEEP MOISTURE BAND ASSOCIATED
WITH THESE FEATURES WILL BE PUSHED A LITTLE MORE SOUTHWARDS TODAY AS
THE PREVAILING LOW-MID LEVEL FLOW ALSO BECOMES MORE WEST-NORTHWEST.
MODELS SHOW SHOWER/STORM COVERAGE NOT QUITE AS HIGH AS THE PAST FEW
DAYS...THOUGH STILL NEAR TO ABOVE NORMAL AT 30-50%. PINPOINTING THE
HIGHEST RAIN COVERAGE WILL BE SOMEWHAT COMPLEX GIVEN WHERE THE
BOUNDARY ENDS UP AND HOW MUCH DRY AIR MANAGES TO WORK ITS WAY IN.
UPSTREAM 29/00Z SOUNDING AT JAX HAD A PWAT OF ONLY 1.55"...MUCH
BELOW THE 2"+ AT TAMPA AND THE CAPE...BUT INDICATES DRIER AIR IS NOT
TOO FAR AWAY. ALSO WINDS LOOK LIGHT ENOUGH FOR A SEA BREEZE TO
DEVELOP NORTH OF THE CAPE IN THE AFTERNOON...WHICH IN COMBINATION
WITH DRIER AIR WILL LIKELY SHIFT RAIN AWAY FROM THE NORTHERN COASTAL
AREAS INTO THE I-4 CORRIDOR. ATMOSPHERE REMAINS WARM ALOFT SO WILL
CONTINUE TO WORD FOR SCATTERED SHOWERS AND ISOLATED STORMS.
THU-WEEKEND...PLAINS MID/UPPER ANTICYCLONE WILL SLOWLY RETROGRADE
WHILE TROUGH GRADUALLY DIGS IN OVER THE EASTERN CONUS. WEAK CUT
OFF LOW EAST OF THE WATERS EARLY SHOULD SHEAR OUT BY SUNDAY AS THE
EASTERN TROUGH DIGS. THE MODELS DO NOT SHOW MUCH SUBSIDENCE/DRYING
ON THE BACK SIDE OF THIS LOW AND KEEP PRECIPITABLE WATER VALUES 2
INCHES OR GREATER THROUGH MOST OF THE PERIOD. ADDITIONALLY...MID
LEVEL TEMPS WILL COOL SLIGHTLY TO AROUND MINUS 7 CELSIUS. EXPECT
THIS WILL LEAD TO AN OVERALL GREATER COVERAGE OF STORMS WITH
INCREASED LIGHTNING ACTIVITY.
STEERING FLOW WILL GRADUALLY WEAKEN...BUT WITH LOW LEVEL RIDGE
SUPPRESSED TO THE SOUTH PROVIDING SOUTHWEST FLOW...SUFFICIENT
FOCUSING FOR STORMS WILL EXIST OVER THE EASTERN SIDE OF THE
PENINSULA.
MOS/CONSENSUS POPS ARE ABOUT 50-60 PERCENT THROUGH THE PERIOD AND
SEE NO REASON TO DIFFER FROM THEM.
MON-WED...THE MODELS SHOW ATLANTIC RIDGE BUILDING BACK ACROSS
THE PENINSULA WED AS THE EASTERN CONUS TROUGH LIFTS AND SOUTHERN
EXTENSION INTO FLORIDA SHIFTS WEST OVER THE GULF OF MEXICO. THIS
REPRESENTS A DELAYED TREND THOUGH...SO EXPECT MOISTURE TO REMAIN
HIGH AND POPS 50 PERCENT OR A LITTLE HIGHER SEEM WARRANTED...EXCEPT
POSSIBLY TRENDING LOWER WED...IF RIDGE DOES INDEED BUILD BACK INTO
CENTRAL FLORIDA.
&&
.AVIATION...
PATCHY MVFR AND IFR CIGS PRESENT AGAIN THIS MORNING THOUGH WITH
CONSIDERABLY LESS AREAL EXTENT THAN THE PAST FEW NIGHTS. WILL KEEP
THE MENTION OF SCT LOW CLOUDS IN SITES THAT HAVE BEEN REPORTING THE
STRATUS AND MONITOR FOR BKN-OVC CONDITIONS. OVERALL THINK ANY CIGS
WILL BE VERY SHORT LIVED.
THE BOUNDARY THAT HAS BEEN FLIRTING WITH THE REGION DROPS BACK
SOUTHWARDS THIS MORNING AND SITES FROM KMLB-KLAL NORTHWARDS WILL SEE
A NW WIND COMPONENT THROUGH MIDDAY. SPEEDS WILL BE LIGHT ENOUGH FOR
SEA BREEZE DEVELOPMENT NORTH OF KTTS...POSSIBLY REACHING AS FAR
INLAND AS KDED IN THE LATE AFTERNOON.
SCT SHRA/ISOLD TSRA DEVELOPING ACROSS THE REGION AFTER 15Z. TEMPO
IFR CIGS/VSBYS WITH ANY CONVECTION WITH A FEW GUSTS TO 35KTS.
&&
.MARINE...
TODAY-TONIGHT...WEAK FRONTAL TROUGH PUSHES SOUTHWARD INTO CENTRAL
FLORIDA WITH N/NW WINDS DEVELOPING NORTH OF THE CAPE TOWARDS
DAYBREAK THIS MORNING WITH WINDS FURTHER SOUTH REMAINING W/SW. LOCAL
OBSERVATIONS SHOW SPEEDS HAVE WEAKENED TO 10-15KTS WITH MODELS
SHOWING SPEEDS AROUND THIS LEVEL THROUGH THE REMAINDER OF THE DAY SO
WILL NOT EXTEND CAUTIONARY STATEMENT. NORTH OF THE CAPE...FLOW WILL
BE LIGHT ENOUGH TO ALLOW SEA BREEZE TO DEVELOP WITH WINDS BECOMING
VARIABLE TO EAST-NORTHEAST IN THE AFTERNOON. W/SW FLOW RE-
ESTABLISHES OVER ALL THE WATERS OVERNIGHT. SEAS WILL BE AROUND 2FT
NEARSHORE 2-3 FEET OFFSHORE.
COVERAGE OF STORMS NOT QUITE AS HIGH AS PREVIOUS FEW DAYS WITH STORM
MOTION BECOMING MORE TO THE SOUTH. HOWEVER STILL COULD SEE A FEW
STORMS PUSHING OFF THE COAST SOUTH OF THE CAPE.
THU-FRI...SURFACE RIDGE AXIS WILL REMAIN SUPPRESSED TO THE SOUTH.
THE PRESSURE GRADIENT LOOKS LIKE IT WILL SUPPORT SOUTHWEST WINDS
AROUND 10 KNOTS NEAR SHORE AND 10 TO 15 KNOTS IN THE OUTER WATERS.
MID LEVEL WIND FLOW IS FORECAST TO WEAKEN BUT WINDS IN THE LOWER
PORTION OF THE ATMOSPHERE OUT OF THE WEST LOOK SUFFICIENT TO PUSH
STORMS OFF THE PENINSULA INTO THE ATLANTIC WATERS. COVERAGE LOOKS
RATHER HIGH AND STORMS SHOULD START TO PRODUCE MORE FREQUENT
LIGHTNING STRIKES.
WEEKEND...LITTLE CHANGE IN THE MOIST SOUTHWEST WIND FLOW REGIME.
BOATERS SHOULD CONTINUE TO BE VIGILANT FOR MARINE STORMS...
ESPECIALLY DURING THE AFTERNOON AND EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 92 75 91 75 / 50 20 60 30
MCO 94 76 91 75 / 50 20 60 30
MLB 92 74 90 74 / 50 20 60 30
VRB 91 73 91 74 / 50 20 60 40
LEE 92 77 90 77 / 50 20 60 30
SFB 92 77 91 76 / 50 20 60 30
ORL 94 77 91 76 / 50 20 60 30
FPR 91 74 91 74 / 40 20 60 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
IMPACT WX...PENDERGRAST
FORECASTS...WIMMER
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
647 AM EDT WED JUL 29 2015
.SYNOPSIS...
ISSUED AT 305 AM EDT WED JUL 29 2015
A WEAK FRONT WILL PASS THROUGH THE GREAT LAKES TODAY BRINGING
THE CHANCE FOR A FEW SHOWERS AND THUNDERSTORMS...MAINLY THIS
AFTERNOON. HIGHS WILL RANGE FROM LOWER 80S NEAR LAKE MICHIGAN TO
THE UPPER 80S IN NORTHWEST OHIO.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM EDT WED JUL 29 2015
POTENT SW DISTURBANCE OVR SRN MB WILL CARRY NEWD INTO
JAMES BAY BY THU AM AS TRAILING SFC BNDRY WASHES OUT ACRS THE LAKES
THIS AFTN. DOWNSTREAM LL FLW WITHIN EWD FOLDING LL THETA-E RIDGE
HWVR REMAINS WK W/H85 WRLY WINDS OF 15KTS OR LESS. THUS IN
COMBINATION W/EWD STREAM OF CONV CLD DEBRIS THROUGH THIS MORNING AND
GENERAL POOR FNTL BASED FORCING AS ASSOCD HGT FALLS W/SW PASS WELL
NORTH. ALL THE MORE REASON TO BACK OFF ON POPS ESP WRN PORTIONS
EARLY ON EVEN IN LIGHT OF RECENT CONV CLUSTER ACRS NE IL WHICH IS
XPCD TO DECAY EWD INTO FAR NW INDIANA PRIOR TO SUNRISE. MEANWHILE
MOST AGREEABLE SHRT TERM GUIDANCE SUGGESTS SOME ISOLD-SCT STORM
DVLPMNT PLAUSIBLE AFT 18Z IN ERN AREAS...I-69 EAST AND GENERALLY
FOLLOWED.
&&
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 305 AM EDT WED JUL 29 2015
UPPER LEVEL LOW CURRENTLY MOVING NORTHEAST THROUGH THE PLAINS WILL
HEAD TOWARDS HUDSON BAY AND REMAIN IN THE GENERAL AREA THROUGH MUCH
OF THE EXTENDED PERIOD. SERIES OF WAVES WILL ROTATE THROUGH THE FLOW
AND MAKE HEADWAY TOWARDS THE GREAT LAKES EVERY FEW DAYS. BEST FOCUS
FOR CHANCES APPEARS TO BE IN THE SUNDAY TO MONDAY TIME FRAME WHEN
PLUME OF MSTR MOVES IN AHEAD OF A SLIGHTLY MORE PRONOUNCED WAVE TO
GIVE SOMEWHAT BETTER CHANCES FOR MEASURABLE RAIN. GRIDS GENERALLY
LEFT ALONE WITH MODELS CONTINUING TO FLIP FLOP ON TIMING/LOCATION OF
BEST CHANCES.
TEMPERATURES WILL REMAIN SEASONABLE IN THE LOWER TO MIDDLE 80S FOR
HIGH THROUGH MUCH OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 645 AM EDT WED JUL 29 2015
VFR CONDS XPCD THROUGH THIS PD. LTL CHANGE FM PRIOR THINKING WRT
WEAKLY FORCED FNTL BNDRY THAT WILL PUSH ACRS THE TERMINALS THIS
AFTN. HWVR BASED ON NR TERM HRRR TRENDS AND XPCD UPSTREAM DECAY OF
NE IL MCS...DELAYED MENTION AT KFWA A BIT LTR.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...T
SHORT TERM...T
LONG TERM...FISHER
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1205 AM EDT WED JUL 29 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 306 PM EDT TUE JUL 28 2015
HOT AND HUMID CONDITIONS WILL PERSIST INTO WEDNESDAY. A COLD FRONT
WILL THEN MOVE INTO CENTRAL INDIANA BRINGING SCATTERED SHOWERS AND
THUNDERSTORMS. DRIER AIR WILL THEN MOVE IN TO END THE WORK WEEK.
ANOTHER FRONT COULD BRING CHANCES FOR RAIN EARLY NEXT WEEK.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 935 PM EDT TUE JUL 28 2015
EARLIER THIS EVENING REMOVED PRECIP CHANCES FROM THE FORECAST AREA
UNTIL LATE DURING THE OVERNIGHT PERIOD AS POP UP SHOWERS AND STORMS
HAVE DISSIPATED ACROSS THE AREA. HRRR AND NAM STILL SHOW SOME STORMS
CURRENTLY OVER IOWA MOVING INTO THE AREA LATE DURING THE OVERNIGHT.
THUS MADE NO CHANGES TO POPS AFTER 6Z AND KEPT BRINGING THEM INTO
THE NORTHWEST AFTER 8Z. OVERNIGHT LOWS IN THE 70S LOOK GOOD BASED ON
DEWPOINTS RIGHT NOW IN THE LOW TO MIDDLE 70S AND NO REAL ADVECTION
GOING ON. TIME HEIGHTS AND CROSSOVER TEMPERATURES ALONG WITH SREF
PROBABILITIES ARE NOT SHOWING MUCH FOR FOG DEVELOPMENT SO WILL
CONTINUE TO LEAVE THAT OUT OF THE FORECAST DESPITE THE AMPLE LOW
LEVEL MOISTURE. PREVIOUS DISCUSSION FOLLOWS...
FOCUS TURNS TO OTHER STORMS MOVING IN LATE. SOME MODELS SHOW STORMS
SURVIVING AND MOVING IN LATE TONIGHT ALONG A PREFRONTAL FEATURE.
WITH SOME WEAK LIFT AROUND...FEEL THAT THIS THREAT LOOKS GOOD ENOUGH
TO GO SLIGHT CHANCE TO LOW END CHANCE POPS 08-12Z.
WITH A HUMID AIRMASS IN PLACE A MODEL BLEND OF TEMPERATURES IN THE
LOW TO MID 70S LOOKS GOOD FOR LOWS.
&&
.SHORT TERM.../WEDNESDAY THROUGH FRIDAY/
ISSUED AT 306 PM EDT TUE JUL 28 2015
FOCUS IS ON CHANCES FOR RAIN WEDNESDAY. MODELS ARE CLOSE ENOUGH THAT
A BLEND WAS USED.
SOME UNCERTAINTY ON HOW CONVECTION WILL DEVELOP AHEAD OF THE A COLD
FRONT ON WEDNESDAY. LINGERING MORNING CONVECTION OR ITS REMNANTS MAY
HELP INHIBIT AFTERNOON CONVECTION. HOWEVER IF IT DIES QUICKLY OR
DOES NOT MAKE IT INTO THE AREA...ATMOSPHERE WILL BE IN GOOD SHAPE
FOR DEVELOPMENT OF AFTERNOON STORMS.
GIVEN THE UNCERTAINTY DECIDED TO KEEP POPS BELOW LIKELY CATEGORY.
TRIED TO TIME HOURLY POPS SO THAT BEST CHANCE OCCURS LATE
MORNING/EARLY AFTERNOON NORTHWEST TO MID AFTERNOON SOUTHEAST WITH
THE TIMING OF THE FRONT.
STUCK WITH MODEL BLEND FOR HIGH TEMPERATURES WEDNESDAY...BUT THESE
TOO MAY DEPEND ON HOW MORNING CONVECTION PLAYS OUT. APPARENT
TEMPERATURES WILL BE NEAR HEAT ADVISORY CRITERIA SOUTHWEST...BUT
THEE CONDITIONS LOOK TO BE RELATIVELY BRIEF. THIS PLUS THE
UNCERTAINTY IN THE RAIN/CLOUD COVER LEADS TO NOT ISSUE A HEAT
ADVISORY.
KEPT SOME LOW END EVENING POPS WEDNESDAY AS THE FRONT MOVES THROUGH.
AFTERWARD...HIGH PRESSURE WILL BUILD IN AND BRING DRY CONDITIONS
INTO FRIDAY. GENERALLY STUCK WITH A MODEL BLEND FOR TEMPERATURES.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 231 PM EDT TUE JUL 28 2015
THE FORECAST FOR THIS WEEKEND IS LOOKING COMPLETELY DRY AS A
LARGE AREA OF HIGH PRESSURE REMAINS IN CONTROL OVER THE REGION.
ENSEMBLES SHOWING A WEAK COLD FRONT NOT MOVING ACROSS OUR REGION
UNTIL EARLY MONDAY...WITH A SECONDARY AND EVEN WEAKER FRONT
FOLLOWING ON TUESDAY. INCLUDED SOME LOW CHANCES FOR SHOWERS AND
STORMS DURING EARLY NEXT WORK WEEK...WITH SLIGHTLY HIGHER POPS
ACROSS THE NORTH...CLOSER TO THESE FEATURES. GENERALLY WENT WITH
SUPERBLEND INITIALIZATION AS THIS GUIDANCE APPEARS TO BE IN LINE
WITH THE CURRENT FORECAST.
&&
.AVIATION /DISCUSSION FOR THE 290600Z TAF ISSUANCE/...
ISSUED AT 1205 AM EDT WED JUL 29 2015
WITH LOWER 70S DEW POINTS...WOULD NOT RULE OUT MVFR FOG OVERNIGHT AT
THE SMALLER AIRPORTS. HOWEVER...INCREASING MID DECK AND CONVECTIVE
DEBRIS AHEAD OF A COLD FRONT...SHOULD KEEP THE VISIBILITY FROM
DROPPING TO IFR OR WORSE SAVE PERHAPS A BRIEF TIME.
RAPID REFRESH REFLECTIVITY PROGS AND RADAR TRENDS SUGGEST THE OWA
CONVECTION COULD MAKE IT IN OUR WESTERN TAF SITES AFTER 10Z AND
EASTERN ONES AFTER 12Z. THE COLD FRONT SHOULD MOVE THROUGH THE AREA
AFTER 23Z WEDNESDAY AT LAF AND HUF AND 01Z THURSDAY AT IND AND BMG.
THIS SHOULD PUT AN END TO ANY OTHER CONVECTION. WILL GO WITH A 2
HOUR MORNING MVFR THUNDERSTORM GROUP AND VCTS TO HANDLE THE
POTENTIAL FOR AFTERNOON RE-DEVELOPMENT.
WINDS WILL BE LIGHT AND VARIABLE TO CALM OVERNIGHT...SOUTHWEST AND
WEST TO LESS THAN 10 KNOTS AFTER DAYBREAK AND NORTHWEST LESS THAN 10
KNOTS THIS EVENING...BEHIND THE FRONT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50/CP
SHORT TERM...50
LONG TERM....SMF
AVIATION...MK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
702 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...31/00Z
ISSUED AT 700 PM CDT THU JUL 30 2015
EXPECT SCATTERED NEBRASKA CONVECTION TO HAVE NO IMPACT ON TAF
SITES AND DISSIPATE WITH LOSS OF HEATING. HIGH CONFIDENCE IN VFR
CONDITIONS THROUGH THE PERIOD WITH LIKELY NOTHING BEYOND SCT MID
CLOUDS AND GENERALLY LIGHT WINDS EVENTUALLY VEERING TO NWLY
DURING FRI PEAK HEATING MIXING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...KOTENBERG
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
754 PM MDT THU JUL 30 2015
.UPDATE...
ISSUED AT 743 PM MDT THU JUL 30 2015
THUNDERSTORMS IN EASTERN COLORADO ARE FOLLOWING A SOUTHWARD
TRAJECTORY WITH THE CLOUD COVER MOVING MORE TO THE EAST/SOUTHEAST.
MODELS INDICATE STORMS SHOULD HAVE ENDED...BUT STORMS CONTINUE TO
MOVE ALONG 500 MB SHORTWAVE TROUGH JUST EAST OF THE 12 C 700 MB
ISOTHERM. AT THE CURRENT SPEED...STRONGER STORMS SHOULD MOVE OUT
OF THE FORECAST AREA BY MIDNIGHT MDT. SLIGHT CHANCES FOR SOME
PRECIPITATION WILL LINGER A LITTLE AFTER MIDNIGHT MDT AS THE SMALL
SHORTWAVE MOVES THROUGH THE HIGH PLAINS.
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 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 520 PM MDT THU JUL 30 2015
A DOME OF UPPER LEVEL HIGH PRESSURE WILL BRING VFR CONDITIONS FOR
BOTH KGLD AND KMCK DURING THE TAF PERIOD. LIGHT AND VARIABLE WINDS
WILL BE EXPERIENCED...AND ANY PREVAILING DIRECTION WILL MAINLY BE
OUT OF THE SOUTHEAST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...MK
SHORT TERM...DR
LONG TERM...JN
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
521 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 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 520 PM MDT THU JUL 30 2015
A DOME OF UPPER LEVEL HIGH PRESSURE WILL BRING VFR CONDITIONS FOR
BOTH KGLD AND KMCK DURING THE TAF PERIOD. LIGHT AND VARIABLE WINDS
WILL BE EXPERIENCED...AND ANY PREVAILING DIRECTION WILL MAINLY BE
OUT OF THE SOUTHEAST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...MK
SHORT TERM...DR
LONG TERM...JN
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
221 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 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1116 AM MDT WED JUL 29 2015
VFR CONDITIONS SHOULD PREVAIL AT BOTH KGLD AND KMCK TERMINALS.
THERE IS A POSSIBILITY FOR 1500 KFT CIGS AT KGLD AROUND
12Z...HOWEVER MOST GUIDANCE IS TRENDING TOWARDS VFR...AND KGLD MAY
BE JUST TO THE NE OF BEST BL MOISTURE AXIS. LIGHT SHOWERS OR
VIRGA WILL CONTINUE TO MOVE WITHIN THE VICINITY OF BOTH KGLD AND
KMCK THIS AFTERNOON WITH GUSTS NEAR THESE SHOWERS AROUND 20KT
POSSIBLE. OTHERWISE WINDS WILL BE LESS THAN 10KT THROUGH THE TAF
PERIOD AS HIGH PRESSURE LINGERS OVER THE REGION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...DR
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
106 AM EDT Wed Jul 29 2015
...Updated Aviation Discussion...
...Forecast Update...
Issued at 830 PM EDT Tue Jul 28 2015
Issued another update to remove the pre-first period wording and to
expand fog coverage. Soupy airmass in place along with winds
expected to become light and variable soon should lead to at least
areas of fog overnight. Quite the complex has formed to our west
this evening, and the residual upper level disturbance may lead to
an enhancement of showers storms toward daybreak, mainly west of the
I-65 corridor. Thus will keep in the slight chances of storms we
have there overnight.
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 (06Z TAF Update)...
Updated 100 AM EDT Tue Jul 28 2015
Steamy conditions will persist overnight, with fog potential being
the biggest near-term question. Rainfall Tue afternoon/evening was
fairly unimpressive near the terminals, and visibilities didn`t drop
too hard in the morning anyway. Temp/dewpoint spreads remain
slightly wider than advertised by models, so it seems that MVFR
should cover the visibilities around daybreak. Best chance of any
IFR restriction seems to be in LEX, as cirrus should keep any fog at
BWG in check.
Next challenge is timing and impact of any convection as a cold
front moves in late in the day. Morning should be high and dry as
the storms over Iowa and northern Missouri struggle to organize into
any kind of MCS that could dive at us early in the day. Hi-res
models all point to mid/late afternoon for any T-storms, and there
remains a hint that some of the are could get gapped. If a storm
does directly affect an airport, there will be MVFR vis in rain, if
not briefly IFR. Will carry a PROB30 group for that into early
evening.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........RJS
Short Term.....AMS
Long Term......ZT
Aviation.......RAS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
835 PM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT MOVES THROUGH THIS EVENING...WITH HIGH PRESSURE
BUILDING IN THE WAKE. A COLD FRONT MAY MOVE THROUGH OVER THE
WEEKEND...WITH THE HIGH PRESSURE RETURNING TO START THE WEEK
BEFORE THE NEXT COLD FRONT MOVES THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
CDFNT NEAR THE BLURDG ATTM...MARKED BY A DROP IN DEWPTS MORE THAN
TEMPS /MID 70S BALT-DC CRRDR VS MID-UPR 50S MRB-HGR-CBE AS OF 00Z/.
STILL A LTL BIT OF INSTBY IN ADVC OF FNT...AS NOTED BY RECURRING
SHRA/TSRA IN CENTRAL VA. HWVR...RECENT HRRR RUNS TAKE THIS ACTIVITY
ESEWD...WHICH MEANS IT/LL BE SE OF CWFA BY 02Z. HV MADE FCST DRY
FOR THE REST OF THE NGT.
SINCE DEWPTS WL BE SLOW TO DROP ACRS CENTRAL VA AND GRND WET FM
LATE DAY RAFL...HV ENTERTAINED PATCHY FOG IN THIS AREA FOR THE
OVNGT HRS-- PRIMARILY FOUND IN SHELTERED VLYS. ELSW...THE SLOW
DROP IN DEWPTS...NOT TO MENTION A LGT /BLO 10 KT/ NWLY FLOW THRU
THE NGT...WL PRECLUDE FOG FORMATION. KEPT TEMPS CLOSE TO LAMP...
WHICH IS QUITE CLOSE TO CLIMO.
HIGH PRESSURE BUILDS IN FRI...KEEPING THE AREA DRY THEN THRU FRI
NIGHT. PLENTY OF WARMING UNDER MOSTLY SUNNY SKIES AND DOWNSLOPING
FROM WLY FLOW ON FRI COULD PUSH TEMPS INTO THE UPPER 80S...TOUCHING
90 IN THE DC AND BALTIMORE METRO AREAS. HOWEVER...WITH THE LOWER
DEW PTS...HEAT ADVISORY CRITERIA IS NOT EXPECTED TO BE REACHED.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE MID ATLANTIC REMAINS UNDER A BROAD UPPER LVL TROUGH AND ON
THE WESTERN PERIPHERY OF HIGH PRESSURE AT THE SFC BY SAT MORNING.
12 MODEL SUITE NOW SUGGESTING THAT A COLD FRONT WILL MOVE THRU
SOMETIME LATE SAT. HOWEVER...ANY UPPER LVL FORCING WITH SHORTWAVE
ENERGY LOOKS TO STILL REMAIN MAINLY NORTH OF THE AREA. WITH A
FAIRLY DRY AIR MASS IN PLACE...PWATS BELOW 1.0 INCHES...EXPECTING
THE FRONTAL PASSAGE TO BE MAINLY DRY...WITH NOTHING MORE THAN A
WIND SHIFT. HAVE KEPT THE LOW END SLIGHT CHC POPS FOR JUST THE FAR
WEST AREAS IN CASE OF TERRAIN DRIVEN CONVECTION. ANYTHING THAT
DOES FORM WILL BE GONE BY SAT EVENING.
THE HIGH PUSHES EAST SAT NIGHT THRU SUN NIGHT...BRINGING DRY AND
QUIET WX TO THE AREA. HIGHS HOVERING IN THE LOW TO UPPER 80S WITH
OVERNIGHT LOWS GENERALLY IN THE 60S.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
HIGH PRESS DOMINATES CONDITIONS SUN NIGHT INTO MONDAY. LATE MON
INTO TUE SWLY FLOW ADVECTS MOISTURE OVER OUR REGION INCREASING
THE CHANCE OF SHOWERS AND TSTMS. A CDFNT APPROACHES TUE NIGHT INTO
WED AND STALLS AROUND OUR AREA THROUGH THU... BRINGING ADDITIONAL
CHANCE OF SHOWERS AND TSTMS FOR THIS PERIOD. TEMPS WILL NEAR
NORMAL SUN AND GRADUALLY INCREASING INTO HE LOW 90S FOR WED.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
TSTMS HV PUSHED E OF THE TERMINALS. VFR CONDS SHUD PREVAIL FOR THE
TAF PERIOD. WINDS ALREADY NW AT MRB...AND SHUD VEER TO THE NW ELSW
BTWN 02-04Z AS A COLD FRONT MVS THRU. WNW FLOW WILL CONTINUE THRU
FRI.
VFR CONDITIONS FRI NIGHT INTO NEXT MONDAY.
&&
.MARINE...
OUTSIDE OF TSRA...WNDS WERE NOT REACHING SCA CRITERIA...SO HV
DROPPED ADVY FOR ALL WATERS. STORMS HV MOSTLY CLEARED THE WATERS
AS WELL...ALTHO RECENT RECURRENT ACTIVITY INVOF EZF SUGGESTS SCTD
SHRA/TSRA STILL PSBL LWR PTMC/MID BAY TIL MIDNGT OR SO.
SLY FLOW WL BECOME NWLY NEAR/AFTR MIDNGT. THERE MAY BE A BRIEF
INCR IN WSPD BHD FNT TIL ABT DAWN...BUT BASED ON MDL SNDGS DO NOT
BELIEVE THESE WINDS WL EXCEED SCA CRITERIA. HV CAPPED WINDS AT 15
KT...MAINLY IN GUSTS.
SUB-SCA CONDITIONS WILL REMAIN IN PLACE FOR THE REST OF FRI...
THRU THE WEEKEND...AND INTO MONDAY WITH HIGH PRESSURE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SEARS/HTS
NEAR TERM...HTS/SEARS
SHORT TERM...SEARS
LONG TERM...IMR
AVIATION...HTS/SEARS/IMR
MARINE...HTS/IMR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
151 AM EDT WED JUL 29 2015
.SYNOPSIS...
HIGH PRESSURE REMAINS OFFSHORE THROUGH MIDWEEK...WITH THE NEXT
COLD FRONT CROSSING THE AREA BY THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
LATEST REGIONAL RADAR MOSAIC DEPICTS AREA OF SHOWERS PERSISTING
OVER THE ERN VA PIEDMONT LATE THIS EVENING...REMAINING GENERALLY
WEST OF THE LOCAL AREA. OTHERWISE...EARLIER SHOWERS/THUNDERSTORMS
HAVE DISSIPATED OVER THE LOCAL AREA. SHORTWAVE VISIBLE ON GOES WV
PROGGED TO DROP OVER ERN VA TONIGHT IN CONCERT WITH INCREASING
WINDS ALOFT. A WARM/MOIST AIR MASS REMAINS IN PLACE OVER THE
LOCAL AREA WITH DEWPOINTS IN THE 70S AND PWATS AROUND 2 INCHES.
WILL MAINTAIN SLIGHT CHANCE-CHANCE POPS OVER THE PIEDMONT INTO
CENTRAL VA AS RAP DEPICTS AN AXIS OF DEEP MOISTURE CONVERGENCE
OVER THAT REGION. SKY AVERAGES PARTLY CLOUDY/MOSTLY CLOUDY INLAND
AND MOSTLY CLEAR NE COUNTIES. LOWS IN THE LOW 70S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
WEDNESDAY...
UPPER LEVEL RIDGING CONTINUES TO EXPAND EASTWARD FROM THE
SOUTHERN PLAINS. THIS WILL HELP TO LIMIT AFTN CONVECTION WHILE MAX
TEMPS WARM A COUPLE OF DEGREES. HAVE CHC POPS (25-30%) ALONG AND
WEST OF I-95. PARTLY SUNNY W/ HIGH TEMPS IN THE UPR 80S TO LOW
90S...WITH LOW/MID 80S AT THE BEACHES. MILD WED NIGHT W/ LOW TEMPS
IN THE LOW/MID 70S.
THURSDAY...
UPR RIDGING RETROGRADES A BIT THURSDAY AS A TROUGH MOVES ACROSS
THE GREAT LAKES AND PUSHES A COLD FRONT INTO THE MID-ATLANTIC
REGION BY LATE IN THE DAY. DUE TO THE LATE ARRIVAL OF THE
FRONT...CHC POPS (30-50%) WILL REMAIN ACROSS WESTERN AREAS DURING
THE AFTN...LOWERING TO ~20% AT THE COAST. MAX TEMPS WILL REACH
INTO THE UPR 80S TO LOW 90S...EXCEPT LOW/MID 80S AT THE IMMEDIATE
COAST.
THURSDAY NIGHT AND FRIDAY...
THE COLD FRONT MOVES ACROSS THE FA THURSDAY NIGHT BEFORE STALLING
ACROSS FAR SE VA AND THE EASTERN CAROLINAS ON FRIDAY. HAVE SOLID
CHANCE POPS (30-50%) MOST AREAS WITH THE PASSAGE OF THE FRONT
THRU MIDDAY FRI...THEN FOCUS CHC POPS ACROSS SE VA AND NE NC
FRIDAY AFTN. DRY WX SHOULD RETURN TO NW AREAS BY LATE MORNING OR
AFTERNOON. LOWS THU NIGHT IN THE 70S. HIGHS FRIDAY IN THE 80S TO
AROUND 90.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
PATTERN BEGINS WITH A MID/UPPER LEVEL RIDGE CENTERED
OVER THE SW CONUS AND AN UPPER LEVEL LOW PERSISTING ACRS HUDSON BAY
CANADA. GFS/ECMWF INTO BETTER DECENT AGREEMENT THAT AN UPPER TROUGH
AXIS WILL EXTEND SOUTH INTO THE GREAT LAKES SAT...THEN FLATTEN OUT
SUN WITH A SHORTWAVE PUSHING ACRS THE MID ATLC BY MON.
FRONT STALLS AND WEAKENS OVER FAR SRN VA/NC LATE FRI INTO THE
WEEKEND. BEST CHC FOR PRECIP LOOKS TO BE ACRS THE FAR SOUTH/MAINLY
NE NC THROUGH THE WEEKEND BUT EVEN HERE WILL ONLY GO WITH A 20-30%
POPS/PRIMARILY FOR THE AFTN/EVENING TIMEFRAME (TAPERED TO 20% FAR
SRN VA AND DRY ELSEWHERE). DID RAISE POPS A BIT FOR MON DUE TO THE
SHORTWAVE MOVING THROUGH BUT NOT A LOT OF CONFIDENCE AS THIS IS 5-6
DAYS OUT SO WILL GENLY KEEP POPS ONLY AT 30-40% SOUTH TO 20% NORTH.
KEEPING POPS AROUND 20% ALL AREAS TUE. TYPICAL SUMMERTIME
TEMPERATURES CAN BE EXPECTED WITH HIGHS MAINLY RANGING FROM THE
MID/UPPER 80S ALONG THE COAST TO THE UPPER 80S TO LOWER 90S INLAND.
LOWS GENERALLY RANGING FROM THE MID 60S NW TO THE LWR 70S SE THROUGH
THE PERIOD.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
UPR LEVEL RIDGING WILL EXPAND EWD FM THE SRN PLAINS TODAY. THIS
WILL HELP TO LIMIT AFTN TSTMS FOR THE ERN HALF OF THE AREA
(INCLUDING TAF SITES KSBY/KPHF/KORF/KECG). HOWEVER...THERE IS
JUST ENOUGH MOISTURE AND ENERGY WRAPPING ARND THE UPR RIDGE TO
KEEP VCSH AT KRIC (INCLUDING AREAS ALONG AND W OF INTERSTATE 95).
OVERALL SHEAR REMAINS VERY WEAK...THEREFORE THE MAIN THREAT WITH
AFTN/EVENING TSTMS WILL BE HEAVY RAINFALL CAUSING QUICK REDUCTIONS
TO CIGS (MVFR) AND VSBYS (IFR). A COLD FRONT WILL THEN SLOWLY PUSH
INTO AND ACRS THE MID ATLC REGION THU THRU FRI AFTN. THIS FRONT
WILL PROVIDE SCTD TSTM CHCS AT ALL TAF SITES DURING THIS PERIOD.
&&
.MARINE...
WEAK SFC HIGH PRESSURE IS CENTERED OFF THE COAST WITH
WEAK SFC TROUGHING INLAND ACRS THE PIEDMONT AND COASTAL PLAIN. S/SE
WINDS AVG 10-15 KT THIS EVENING/OVERNIGHT...AND WILL DROP OFF TO
S/SW 5-10 KT WED MORNING. MODELS SUGGEST THAT WINDS MAY BE A LITTLE
STRONGER LATE WED AFTN/WED NIGHT AS SFC/LEE TROUGH OVER VA DEEPENS
SLIGHTLY AND HELPS S/SE WINDS AVG AROUND 15 KT IN THE BAY. COULD BE
A FEW HRS WORTH OF 20 KT GUSTS IN THE BAY BUT TOO MARGINAL TO
CONSIDER ANY SCA HEADLINES FOR NOW. WAVES GENLY 1-2 FT IN THE
BAY BUT WILL PROBABLY BUILD TO 2-3 FT WED EVENING. SEAS 2-3 FT.
A WEAK COLD FRONT APPROACHES THE WATERS LATE THU...THEN STALLS SOUTH
OF THE AREA BY LATE IN THE WEEK. S/SE WINDS AVG 10-15 KT...TURNING
SSW THU NIGHT. NOT A STRONG COOL SURGE ON FRI AS WINDS SHIFT TO THE
NORTH WITH THE FRONT DISSIPATING OVER SRN VA/ERN NC SO WILL KEEP
WINDS IN THE 10-15 KT RANGE. FLOW GRADUALLY SHIFTS TO E/SE INTO THE
WEEKEND WITH WAVES 1-2 FT/SEAS 2-4 FT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JDM
NEAR TERM...JDM/SAM
SHORT TERM...JDM
LONG TERM...LKB
AVIATION...TMG
MARINE...LKB/TMG
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
242 PM EDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EDT WED JUL 29 2015
FAIRLY IMPRESSIVE SURFACE AND UPPER LOW FOR LATE JULY IS LOCATED
JUST TO THE SOUTH OF LAKE WINNIPEG EARLY THIS MORNING...AND IT IS
KEEPING MUCH OF ITS ENERGY NEAR THE LOW IN MANITOBA. THIS HAS LED TO
A FAIRLY UNEVENTFUL PASSAGE OF THE COLD FRONT DUE TO THE LACK OF ANY
UPPER LEVEL SUPPORT/SHORTWAVES MOVING THROUGH THE AREA AND THE MID-
LEVEL DRY AIR AND CAPPING SEEN ON RAP ANALYSIS SOUNDINGS. THERE WAS
A THUNDERSTORM THAT MOVED NORTHEAST OUT OF NORTHWEST WISCONSIN
EARLIER IN THE NIGHT BUT DISSIPATED OVER WESTERN LAKE SUPERIOR. HAVE
SEEN SOME LIGHT SHOWER DEVELOPMENT OVER THE WESTERN U.P. OVER THE
LAST 1-2HRS AND THEY ARE MOVING NORTHEAST WHILE THE FRONT SHIFTS
THEM TO THE EAST. THERE HASN/T BEEN ANY LIGHTNING NOTED WITH THEM
THUS FAR...LARGELY DUE TO THEM STRUGGLING TO GET ABOVE THE FREEZING
LEVEL (HAVE PEAKED AROUND 15KFT). STILL THINK SOME THUNDER IS
POSSIBLE AS THEY ALIGN WITH A THIN AREA OF 500 J/KG OF MUCAPE AHEAD
OF THE FRONT AS SEEN ON THE SPC MESOSCALE ANALYSIS PAGE. THE COLD
FRONT WILL CONTINUE TO THE EAST THIS MORNING AND EXIT THE AREA BY
NOON. WILL CONTINUE TO SHOW SLIGHT CHANCE POPS RIGHT ALONG THE FRONT
AS IT MOVES EAST THIS MORNING...BUT DON/T EXPECT ANYTHING MORE THAN
AN ISOLATED SHOWER/THUNDERSTORM. HAVE SEEN A FAIRLY SIGNIFICANT DROP
IN DEWPOINTS BEHIND THE FRONT...AS KIWD WENT FROM A 72 DEGREE
DEWPOINT AT 535Z AND QUICKLY DROPPED TO 64 AT 615Z AND IS NOW AT 57
AT 735Z.
BEHIND THE FRONT...THE DRY SLOT SEEN ON WATER VAPOR IMAGERY WILL
MOVE THROUGH THE AREA AND LEAD TO AN AREA OF MOSTLY SUNNY START TO
THE DAY OVER THE WEST. DO EXPECT THE AREA OF CLOUDS IN NORTHEAST ND
AND NORTHWEST MN TO MOVE EAST INTO THE WESTERN CWA THIS AFTERNOON
AND BE AIDED BY DIURNAL HEATING TO PRODUCE DIURNAL CU ON THE LEADING
EDGE AND AHEAD OF THE CLOUDS INTO THE CENTRAL U.P. OVER THE
EAST...AFTER A CLOUDY START TO THE DAY...EXPECT A PERIOD OF MOSTLY
SUNNY SKIES AND THEN SOME DIURNAL CU IN AFTERNOON AND LINGERING INTO
THE EVENING. HIGHS TODAY WILL BE IN THE UPPER 70S OVER THE WEST AND
THE LOW-MID 80S OVER THE CENTRAL AND EAST.
THE MAIN HAZARD BEHIND THE FRONT WILL BE THE GUSTY WEST-SOUTHWEST
WINDS. THESE WINDS WILL BE AIDED BY THE TIGHT PRESSURE GRADIENT OVER
THE NORTHWEST HALF OF THE CWA AND LARGELY OVER NORTHWESTERN LAKE
SUPERIOR. HAVE ALREADY SEEN GUSTS TO 20-25KTS IMMEDIATELY BEHIND THE
FRONT EARLIER IN THE NIGHT AND CLOSER TO THE LOW WINDS HAVE BEEN
GUSTING TO 30-35KTS IN NORTHWEST MINNESOTA. THE AMPLE SUNSHINE THIS
MORNING WILL HELP TO MIX INTO THE 25-40KT WINDS AROUND 925MB TO THE
SURFACE...WITH THE STRONGEST WINDS OVER THE KEWEENAW PENINSULA. IN
THAT AREA...WOULD EXPECT GUSTS TO AROUND 35KTS BY MID AFTERNOON AND
THERE COULD BE A BRIEF PERIOD OF GUSTS TO 40KTS BY EARLY EVENING.
DON/T THINK THERE WILL BE A LONG ENOUGH PERIOD FOR A WIND ADVISORY
FOR THE KEWEENAW PENINSULA (NEED 39KTS)...SO WILL ISSUE AN SPS FOR
KEWEENAW AND NORTHERN HOUGHTON COUNTIES TO HIGHLIGHT THE WINDY
CONDITIONS FOR TODAY. THE REST OF THE U.P. WILL SEE WIND GUSTS OF 20-
30KTS...HIGHEST OVER THE WEST.
WITH THE MUCH DRIER AIR MOVING INTO THE AREA...THINK DEWPOINTS WILL
MIX OUT INTO THE UPPER 40S TO AROUND 50 OVER THE WEST/CENTRAL TODAY.
WHILE TEMPERATURES WILL BE COOLER THAN YESTERDAY...RH VALUES WILL
STILL FALL INTO THE 30S. THAT WILL LEAD TO AN ELEVATED RISK OF
WILDFIRES ACROSS MUCH OF THE U.P. TODAY. SINCE THE RH VALUES WILL BE
ABOVE RED FLAG CRITERIA...THIS SITUATION WOULD FALL UNDER AN RFD
PRODUCT DUE TO THE FREQUENT GUSTS OVER 25 MPH. SINCE COORDINATION
NEEDS TO BE DONE WITH FIRE WX USERS BEFORE ISSUANCE...WILL PASS
ALONG TO DAY SHIFT TO COORDINATE POTENTIAL ISSUANCE.
A SECONDARY TROUGH MOVES EAST ACROSS THE AREA TONIGHT. SOME CLOUDS
ASSOCIATED WITH IT...LARGELY OVER LAKE SUPERIOR...BUT NOT EXPECTING
ANY RAIN. THERE WILL STILL BE STRONG WINDS JUST ABOVE THE SURFACE
AGAIN TONIGHT...WHICH WILL HELP TO KEEP THE WINDS FROM DECOUPLING.
HAVE KEPT UP GUSTS OVER THE KEWEENAW PENINSULA (TO 20-30KTS)
...ESPECIALLY FOR THE EXPOSED LOCATIONS. OTHERWISE...THE REST OF THE
AREA WILL SEE WINDS TURNING WESTERLY WITH GUSTS TO 10-20KTS (HIGHEST
NORTH).
.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 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 144 PM EDT WED JUL 29 2015
GUSTY WEST-SOUTHWEST WINDS ARE EXPECTED AT ALL THREE SITES
THIS AFTEROON...WITH THE HIGHEST GUSTS (TO AROUND 35KTS) EXPECTED AT
KCMX. THE WINDS WILL DIMINISH SOME AT ALL THREE SITES TONIGHT...BUT
STILL EXPECT GUSTS TO 25KTS AT KCMX. VFR CU/SC CIG IS EXPECTED
THROUGH THIS AFTERNOON AT IWD/CMX WITH FEW-SCATTERED VFR CLOUDS WITH
LINGERING INTO TONIGHT. OTHERWISE...EXPECT MAINLY JUST SCT CU AT
SAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EDT WED JUL 29 2015
A STRONG LOW PRESSURE SYSTEM FOR LATE JULY IS LOCATED NEAR LAKE
WINNIPEG EARLY THIS MORNING AND IT WILL LIFT NORTHEAST INTO FAR
NORTHERN ONTARIO TODAY. MEANWHILE...IT WILL SWEEP A COLD FRONT
CURRENTLY OVER CENTRAL LAKE SUPERIOR EAST ACROSS THE REST OF THE
LAKE THIS MORNING. BEHIND THE FRONT...SOUTHWEST WINDS WILL
INCREASE THROUGH THE MORNING OVER THE WESTERN HALF OF THE LAKE AND
PRODUCE GALES TO 35-40KTS. THERE COULD BE A FEW GUSTS IN THE 40-45KT
RANGE TOWARDS ISLE ROYALE THIS AFTERNOON. THESE WINDS WILL DECREASE
AND SHIFT TO THE WEST THIS EVENING AS THE FIRST IN A SERIES OF
TROUGHS MOVE ACROSS LAKE SUPERIOR THROUGH SUNDAY MORNING (ASSOCIATED
WITH THE SURFACE LOW SLOWLY DRIFTING OVER HUDSON BAY). THERE IS THE
POTENTIAL FOR GALES OUT OF THE WEST-NORTHWEST TONIGHT BEHIND THE
SECONDARY TROUGH AS THE PRESSURE GRADIENT REMAINS TIGHT OVER
NORTHERN LAKE SUPERIOR. BUT EXPECT THE MARINE LAYER TO BE THE
STRONGEST IN THAT AREA WITH THE WATER TEMPERATURES STILL IN THE
UPPER 30S AND LOWER 40S. WILL ADD A MENTION OF GALE FORCE GUSTS FOR
NOW. THE PRESSURE GRADIENT WILL GRADUALLY DECREASE THROUGH THE REST
OF THE WEAK AS ADDITIONAL WEAK SURFACE TROUGHS MOVE SOUTHEAST ACROSS
THE LAKE. EXPECT WINDS TO STAY BELOW 25KTS AFTER THURSDAY AND
THROUGH THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR LSZ162-
240>242-245>247-263.
GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ264.
GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR LSZ243-244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...TITUS
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
144 PM EDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EDT WED JUL 29 2015
FAIRLY IMPRESSIVE SURFACE AND UPPER LOW FOR LATE JULY IS LOCATED
JUST TO THE SOUTH OF LAKE WINNIPEG EARLY THIS MORNING...AND IT IS
KEEPING MUCH OF ITS ENERGY NEAR THE LOW IN MANITOBA. THIS HAS LED TO
A FAIRLY UNEVENTFUL PASSAGE OF THE COLD FRONT DUE TO THE LACK OF ANY
UPPER LEVEL SUPPORT/SHORTWAVES MOVING THROUGH THE AREA AND THE MID-
LEVEL DRY AIR AND CAPPING SEEN ON RAP ANALYSIS SOUNDINGS. THERE WAS
A THUNDERSTORM THAT MOVED NORTHEAST OUT OF NORTHWEST WISCONSIN
EARLIER IN THE NIGHT BUT DISSIPATED OVER WESTERN LAKE SUPERIOR. HAVE
SEEN SOME LIGHT SHOWER DEVELOPMENT OVER THE WESTERN U.P. OVER THE
LAST 1-2HRS AND THEY ARE MOVING NORTHEAST WHILE THE FRONT SHIFTS
THEM TO THE EAST. THERE HASN/T BEEN ANY LIGHTNING NOTED WITH THEM
THUS FAR...LARGELY DUE TO THEM STRUGGLING TO GET ABOVE THE FREEZING
LEVEL (HAVE PEAKED AROUND 15KFT). STILL THINK SOME THUNDER IS
POSSIBLE AS THEY ALIGN WITH A THIN AREA OF 500 J/KG OF MUCAPE AHEAD
OF THE FRONT AS SEEN ON THE SPC MESOSCALE ANALYSIS PAGE. THE COLD
FRONT WILL CONTINUE TO THE EAST THIS MORNING AND EXIT THE AREA BY
NOON. WILL CONTINUE TO SHOW SLIGHT CHANCE POPS RIGHT ALONG THE FRONT
AS IT MOVES EAST THIS MORNING...BUT DON/T EXPECT ANYTHING MORE THAN
AN ISOLATED SHOWER/THUNDERSTORM. HAVE SEEN A FAIRLY SIGNIFICANT DROP
IN DEWPOINTS BEHIND THE FRONT...AS KIWD WENT FROM A 72 DEGREE
DEWPOINT AT 535Z AND QUICKLY DROPPED TO 64 AT 615Z AND IS NOW AT 57
AT 735Z.
BEHIND THE FRONT...THE DRY SLOT SEEN ON WATER VAPOR IMAGERY WILL
MOVE THROUGH THE AREA AND LEAD TO AN AREA OF MOSTLY SUNNY START TO
THE DAY OVER THE WEST. DO EXPECT THE AREA OF CLOUDS IN NORTHEAST ND
AND NORTHWEST MN TO MOVE EAST INTO THE WESTERN CWA THIS AFTERNOON
AND BE AIDED BY DIURNAL HEATING TO PRODUCE DIURNAL CU ON THE LEADING
EDGE AND AHEAD OF THE CLOUDS INTO THE CENTRAL U.P. OVER THE
EAST...AFTER A CLOUDY START TO THE DAY...EXPECT A PERIOD OF MOSTLY
SUNNY SKIES AND THEN SOME DIURNAL CU IN AFTERNOON AND LINGERING INTO
THE EVENING. HIGHS TODAY WILL BE IN THE UPPER 70S OVER THE WEST AND
THE LOW-MID 80S OVER THE CENTRAL AND EAST.
THE MAIN HAZARD BEHIND THE FRONT WILL BE THE GUSTY WEST-SOUTHWEST
WINDS. THESE WINDS WILL BE AIDED BY THE TIGHT PRESSURE GRADIENT OVER
THE NORTHWEST HALF OF THE CWA AND LARGELY OVER NORTHWESTERN LAKE
SUPERIOR. HAVE ALREADY SEEN GUSTS TO 20-25KTS IMMEDIATELY BEHIND THE
FRONT EARLIER IN THE NIGHT AND CLOSER TO THE LOW WINDS HAVE BEEN
GUSTING TO 30-35KTS IN NORTHWEST MINNESOTA. THE AMPLE SUNSHINE THIS
MORNING WILL HELP TO MIX INTO THE 25-40KT WINDS AROUND 925MB TO THE
SURFACE...WITH THE STRONGEST WINDS OVER THE KEWEENAW PENINSULA. IN
THAT AREA...WOULD EXPECT GUSTS TO AROUND 35KTS BY MID AFTERNOON AND
THERE COULD BE A BRIEF PERIOD OF GUSTS TO 40KTS BY EARLY EVENING.
DON/T THINK THERE WILL BE A LONG ENOUGH PERIOD FOR A WIND ADVISORY
FOR THE KEWEENAW PENINSULA (NEED 39KTS)...SO WILL ISSUE AN SPS FOR
KEWEENAW AND NORTHERN HOUGHTON COUNTIES TO HIGHLIGHT THE WINDY
CONDITIONS FOR TODAY. THE REST OF THE U.P. WILL SEE WIND GUSTS OF 20-
30KTS...HIGHEST OVER THE WEST.
WITH THE MUCH DRIER AIR MOVING INTO THE AREA...THINK DEWPOINTS WILL
MIX OUT INTO THE UPPER 40S TO AROUND 50 OVER THE WEST/CENTRAL TODAY.
WHILE TEMPERATURES WILL BE COOLER THAN YESTERDAY...RH VALUES WILL
STILL FALL INTO THE 30S. THAT WILL LEAD TO AN ELEVATED RISK OF
WILDFIRES ACROSS MUCH OF THE U.P. TODAY. SINCE THE RH VALUES WILL BE
ABOVE RED FLAG CRITERIA...THIS SITUATION WOULD FALL UNDER AN RFD
PRODUCT DUE TO THE FREQUENT GUSTS OVER 25 MPH. SINCE COORDINATION
NEEDS TO BE DONE WITH FIRE WX USERS BEFORE ISSUANCE...WILL PASS
ALONG TO DAY SHIFT TO COORDINATE POTENTIAL ISSUANCE.
A SECONDARY TROUGH MOVES EAST ACROSS THE AREA TONIGHT. SOME CLOUDS
ASSOCIATED WITH IT...LARGELY OVER LAKE SUPERIOR...BUT NOT EXPECTING
ANY RAIN. THERE WILL STILL BE STRONG WINDS JUST ABOVE THE SURFACE
AGAIN TONIGHT...WHICH WILL HELP TO KEEP THE WINDS FROM DECOUPLING.
HAVE KEPT UP GUSTS OVER THE KEWEENAW PENINSULA (TO 20-30KTS)
...ESPECIALLY FOR THE EXPOSED LOCATIONS. OTHERWISE...THE REST OF THE
AREA WILL SEE WINDS TURNING WESTERLY WITH GUSTS TO 10-20KTS (HIGHEST
NORTH).
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 455 AM EDT WED JUL 29 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA AND A BROAD RIDGE IS
ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE FEATURES A NW
FLOW WILL DOMINATE THE GREAT LAKES REGION AS A SERIES OF MAINLY WEAK
SHORTWAVES PASSING THRU BRING CHCS FOR PERIODIC LIGHT SHOWERS.
TIMING OF THESE WEAK SHORTWAVES WILL LIKELY BE 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
TREND BELOW NORMAL TOWARD THE BEGINNING HALF OF NEXT WEEK AS A MID-
LVL TROUGH BEGINS TO AMPLIFY INTO THE UPPER GREAT LAKES REGION.
THU THROUGH FRI...MOST OF MODELS SHOW A WEAK SHORTWAVE MOVING
THROUGH THE AREA TOWARD THU EVENING WITH ANOTHER WEAK SHORTWAVE
MOVING THROUGH DURING THE DAY ON FRI. WITH SEVERAL OF THE MODELS
SHOWING A FEW HUNDRED J/KG OF MLCAPE EACH DAY MAINLY DURING THE
AFTERNOON/EVENING HRS WILL PROBABLY NEED TO MAINTAIN SLIGHT CHC POPS
EACH DAY FOR ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW
EXPECT ANY PCPN FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
FRI NIGHT AND SAT...ANOTHER SHORTWAVE MOVING THROUGH DURING THIS
TIME WILL WARRANT HAVING SLIGHT CHC POPS OVER MAINLY THE NW AND NE
CWA INCLUDING LAKE SUPERIOR.
TEMPERATURES THU THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS HAVE TRENDED FARTHER NORTH WITH MORE SIGNIFICANT SHORTWAVE
DUE TO MOVE IN SAT NIGHT INTO SUN SO HAVE BACKED OFF TO ONLY SLIGHT
CHANCE POPS FOR THAT TIME FRAME. BEST LIFT WITH SHORTWAVE STAYS
NORTH AND BETTER INSTABILITY AS INDICATED BY MODELS IS FARTHER
SOUTH.
TIMING OF SHORTWAVE AND ASSOC COLD FRONT FOR EARLY NEXT WEEK
DIFFERS BTWN THE 00Z GFS AND 00Z ECMWF. THE ECMWF IS QUICKER
BRINGING SYSTEM THROUGH SUN NIGHT INTO MON WHILE THE GFS DOESN/T
BRING SYSTEM THRU UNTIL LATE MON INTO MON NIGHT. THIS SYSTEM MAY
HAVE A BETTER CHC OF BRINGING MORE WIDESPREAD...ALTHOUGH LIGHT
PCPN...BUT GIVEN UNCERTAINTY IN TIMING AT THIS POINT DON/T HAVE
ANYTHING MORE THAN LOW CHC POPS. MODELS ADVERTISE TEMPS COOLING BELOW
NORMAL TEMPS BEHIND THE FRONTAL SYSTEM ESPECIALLY BY TUE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 144 PM EDT WED JUL 29 2015
GUSTY WEST-SOUTHWEST WINDS ARE EXPECTED AT ALL THREE SITES
THIS AFTEROON...WITH THE HIGHEST GUSTS (TO AROUND 35KTS) EXPECTED AT
KCMX. THE WINDS WILL DIMINISH SOME AT ALL THREE SITES TONIGHT...BUT
STILL EXPECT GUSTS TO 25KTS AT KCMX. VFR CU/SC CIG IS EXPECTED
THROUGH THIS AFTERNOON AT IWD/CMX WITH FEW-SCATTERED VFR CLOUDS WITH
LINGERING INTO TONIGHT. OTHERWISE...EXPECT MAINLY JUST SCT CU AT
SAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EDT WED JUL 29 2015
A STRONG LOW PRESSURE SYSTEM FOR LATE JULY IS LOCATED NEAR LAKE
WINNIPEG EARLY THIS MORNING AND IT WILL LIFT NORTHEAST INTO FAR
NORTHERN ONTARIO TODAY. MEANWHILE...IT WILL SWEEP A COLD FRONT
CURRENTLY OVER CENTRAL LAKE SUPERIOR EAST ACROSS THE REST OF THE
LAKE THIS MORNING. BEHIND THE FRONT...SOUTHWEST WINDS WILL
INCREASE THROUGH THE MORNING OVER THE WESTERN HALF OF THE LAKE AND
PRODUCE GALES TO 35-40KTS. THERE COULD BE A FEW GUSTS IN THE 40-45KT
RANGE TOWARDS ISLE ROYALE THIS AFTERNOON. THESE WINDS WILL DECREASE
AND SHIFT TO THE WEST THIS EVENING AS THE FIRST IN A SERIES OF
TROUGHS MOVE ACROSS LAKE SUPERIOR THROUGH SUNDAY MORNING (ASSOCIATED
WITH THE SURFACE LOW SLOWLY DRIFTING OVER HUDSON BAY). THERE IS THE
POTENTIAL FOR GALES OUT OF THE WEST-NORTHWEST TONIGHT BEHIND THE
SECONDARY TROUGH AS THE PRESSURE GRADIENT REMAINS TIGHT OVER
NORTHERN LAKE SUPERIOR. BUT EXPECT THE MARINE LAYER TO BE THE
STRONGEST IN THAT AREA WITH THE WATER TEMPERATURES STILL IN THE
UPPER 30S AND LOWER 40S. WILL ADD A MENTION OF GALE FORCE GUSTS FOR
NOW. THE PRESSURE GRADIENT WILL GRADUALLY DECREASE THROUGH THE REST
OF THE WEAK AS ADDITIONAL WEAK SURFACE TROUGHS MOVE SOUTHEAST ACROSS
THE LAKE. EXPECT WINDS TO STAY BELOW 25KTS AFTER THURSDAY AND
THROUGH THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR LSZ162-
240>242-245>247-263.
GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ264.
GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR LSZ243-244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
123 PM EDT WED JUL 29 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EDT WED JUL 29 2015
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A COLD
FRONT CROSSES THE REGION. GUSTY WESTERLY WINDS BEHIND THE FRONT WILL
USHER IN MORE COMFORTABLE LESS HUMID AIR FOR THE REMAINDER OF THE
WEEK ALTHOUGH HIGHS WILL REMAIN IN THE LOWER TO MID 80S.
&&
.UPDATE...
ISSUED AT 1044 AM EDT WED JUL 29 2015
DECREASED POPS A BIT BASED ON RADAR TRENDS. A WEAK COLD FRONT IS
MOVING ACROSS LAKE MICHIGAN ATTM AND MAY KICK OFF A STORM OR TWO
THIS AFTERNOON MAINLY ACROSS THE EASTERN CWA.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
ISOLATED SHOWERS HAVE DEVELOPED OVERNIGHT ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER AROUND TWO INCHES MOVING IN FROM THE
SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT. SUSPECT COVERAGE OF
SHOWERS WILL REMAIN RATHER LIMITED THIS MORNING ACROSS SW LWR MI AS
MORE EXPANSIVE AREA OF CONVECTION IMPACTS IOWA AND ILLINOIS.
OUR BEST PROSPECT FOR BETTER COVERAGE OF STORMS WILL BE THIS
AFTERNOON EAST OF HIGHWAY 131 WHERE SB CAPES NEAR 1500 J/KG ARE
PROGGED JUST AHEAD OF THE FRONT. RUC FCST SOUNDINGS EXHIBIT STEEP
LOW LEVEL LAPSE RATES WITH SFC TO 3 KM VALUES AROUND 8.5C NEAR
JXN. BASED ON THE HIGH PWAT VALUES OF UP TO 2.25 INCHES WE WILL
HAVE TO WATCH FOR THE POSSIBILITY OF SOME TORRENTIAL RAINFALL AND
POSSIBLY A LOCALIZED WET MICROBURST DAMAGING WIND EVENT.
CONVECTION ENDS FROM WEST TO EAST 18Z-22Z WITH THE PASSAGE OF THE
FRONT THEN DECREASING CLOUDS AND FALLING SFC DEW PTS EXPECTED.
BREEZY CONDITIONS LIKELY THURSDAY ONCE DEEPER MIXING COMMENCES.
SOME GUSTS TO 30 MPH WILL BE POSSIBLE IN THE AFTERNOON.
HAVE KEPT FRIDAY DRY FOR NOW ALTHOUGH SOME SMALL POPS MAY NEED TO
BE ADDED IN LATER FCSTS AS NEXT WEAK SFC FRONT/TROUGH DROPS SOUTH.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
THERE HAS NOT BEEN MUCH CHANGE OVER THE THE PAST FEW DAYS WITH
REGARD TO THE EXPECTED PATTERN. WE CONTINUE TO EXPECT LITTLE TO NO
RAIN THROUGH SAT...BEFORE AN UNSETTLED WEATHER PATTERN TAKES SHAPE
LATER THIS WEEKEND AND INTO NEXT WEEK.
WE HAVE CONTINUED WITH A DRY FCST FOR THE FRI NIGHT AND SAT TIME
FRAME FOR NOW. WE WILL SEE WHAT IS LEFT OF THE WEAKENING COLD FRONT
TRYING TO MOVE THROUGH ON FRI SLIP SE OF THE AREA FRI EVENING. WE
CAN NOT RULE OUT A SHOWER DEVELOPING NEAR THIS FRONT...HOWEVER THE
CHC IS LOW ENOUGH TO LEAVE OUT OF THE FCST FOR THE TIME BEING. A
LACK OF MOISTURE WITH THE FRI FRONT WILL ONLY DIMINISH BY SAT AS THE
FRONT MOVES OUT. THERE IS NOT REALLY SIGNIFICANTLY COOLER AIR BEHIND
THIS...SO WE CONTINUE TO EXPECT HIGHS AROUND 80.
THE CHCS OF RAIN DOES GO UP ON SUN...AND WILL CONTINUE THROUGH THE
END OF THE PERIOD ON TUE. THE AREA WILL BE UNDER THE INFLUENCE OF
BROAD LONG WAVE TROUGHING CENTERED WELL NORTH IN CANADA. WE WILL SEE
THE JET CORE DROP A LITTLE FURTHER SOUTH WITH A TRAIN OF SHORT WAVES
HELPING THIS CAUSE. BEING CLOSER TO THE JET...WE WILL HAVE MORE OF
AN OPPORTUNITY FOR THE SHORT WAVES TO DIRECTLY IMPACT THE AREA. WE
WILL ALSO SEE THE LOW LEVEL FLOW BECOME A LITTLE MORE FAVORABLE TO
BRING SUFFICIENT MOISTURE TO THE AREA FOR RAIN. EXACT TIMING OF THE
SHORT WAVES WILL BE PROBLEMATIC AS IS USUAL IN A PATTERN LIKE THIS.
TEMPERATURES DO NOT LOOK TO BE TOO BAD IN THIS PATTERN. THE
UNSEASONABLY COOL AIR WILL REMAIN JUST NORTH OF THE STATE...NORTH OF
THE JET CORE. WE WILL SEE AVERAGE TO JUST SLIGHTLY BELOW AVERAGE
TEMPS DURING THIS PERIOD FOR OUR AREA. THIS EQUATES TO HIGHS
GENERALLY AROUND 80 AND LOWS AROUND 60.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 122 PM EDT WED JUL 29 2015
THERE IS A NARROW BAND OF MVFR CIGS THAT TRAIL THE FRONT...THIS
WILL LAST ABOUT 2 HOURS AT ANY ONE STATION. IT HAS ALREADY CLEARED
THE MKG TAF SITE AND SHOULD BE CLEARING THE GRR...AZO AND BTL TAF
SITES BY 20Z. AHEAD OF THE FRONT CONVECTION IS STARTING TO DEVELOP
SO THE LAN AND JXN TAF SITES COULD SEE A THUNDERSTORM PRIOR TO THE
PASSAGE OF THE FRONT. THE FRONT SHOULD BE PASSING THROUGH THOSE
TAF SITES BY 21Z.
TONIGHT SKIES SHOULD BE CLEAR AND WINDS SHOULD BE SOUTHWEST UNDER
10 KNOTS. WINDS WILL INCREASE TO 10 TO 20 KNOTS AND GUSTY THURSDAY
AS COOLER AIR AT MID LEVELS MOVES IN. SKIES SHOULD REMAIN CLEAR OR
AT LEAST NEARLY SO.
&&
.MARINE...
ISSUED AT 330 AM EDT WED JUL 29 2015
CONDITIONS MAY APPROACH SMALL CRAFT ADVISORY CRITERIA LATE TONIGHT
AND EARLY THURSDAY DUE TO STRONG WESTERLY FLOW BEHIND THE COLD
FRONT. THIS WILL NEED TO BE MONITORED. THIS SITUATION COULD ALSO
SUPPORT BEACH HAZARD STATEMENTS ESPECIALLY CONSIDERING THE CURRENT
WARM WATER TEMPERATURES AND OVERALL ATTRACTIVE BEACH CONDITIONS
SUPPORTIVE OF A HIGH BEACH POPULATION.
&&
.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.
&&
$$
UPDATE...04
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1151 AM EDT WED JUL 29 2015
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 330 AM EDT WED JUL 29 2015
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A COLD
FRONT CROSSES THE REGION. GUSTY WESTERLY WINDS BEHIND THE FRONT WILL
USHER IN MORE COMFORTABLE LESS HUMID AIR FOR THE REMAINDER OF THE
WEEK ALTHOUGH HIGHS WILL REMAIN IN THE LOWER TO MID 80S.
&&
.UPDATE...
ISSUED AT 1044 AM EDT WED JUL 29 2015
DECREASED POPS A BIT BASED ON RADAR TRENDS. A WEAK COLD FRONT IS
MOVING ACROSS LAKE MICHIGAN ATTM AND MAY KICK OFF A STORM OR TWO
THIS AFTERNOON MAINLY ACROSS THE EASTERN CWA.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
ISOLATED SHOWERS HAVE DEVELOPED OVERNIGHT ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER AROUND TWO INCHES MOVING IN FROM THE
SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT. SUSPECT COVERAGE OF
SHOWERS WILL REMAIN RATHER LIMITED THIS MORNING ACROSS SW LWR MI AS
MORE EXPANSIVE AREA OF CONVECTION IMPACTS IOWA AND ILLINOIS.
OUR BEST PROSPECT FOR BETTER COVERAGE OF STORMS WILL BE THIS
AFTERNOON EAST OF HIGHWAY 131 WHERE SB CAPES NEAR 1500 J/KG ARE
PROGGED JUST AHEAD OF THE FRONT. RUC FCST SOUNDINGS EXHIBIT STEEP
LOW LEVEL LAPSE RATES WITH SFC TO 3 KM VALUES AROUND 8.5C NEAR
JXN. BASED ON THE HIGH PWAT VALUES OF UP TO 2.25 INCHES WE WILL
HAVE TO WATCH FOR THE POSSIBILITY OF SOME TORRENTIAL RAINFALL AND
POSSIBLY A LOCALIZED WET MICROBURST DAMAGING WIND EVENT.
CONVECTION ENDS FROM WEST TO EAST 18Z-22Z WITH THE PASSAGE OF THE
FRONT THEN DECREASING CLOUDS AND FALLING SFC DEW PTS EXPECTED.
BREEZY CONDITIONS LIKELY THURSDAY ONCE DEEPER MIXING COMMENCES.
SOME GUSTS TO 30 MPH WILL BE POSSIBLE IN THE AFTERNOON.
HAVE KEPT FRIDAY DRY FOR NOW ALTHOUGH SOME SMALL POPS MAY NEED TO
BE ADDED IN LATER FCSTS AS NEXT WEAK SFC FRONT/TROUGH DROPS SOUTH.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
THERE HAS NOT BEEN MUCH CHANGE OVER THE THE PAST FEW DAYS WITH
REGARD TO THE EXPECTED PATTERN. WE CONTINUE TO EXPECT LITTLE TO NO
RAIN THROUGH SAT...BEFORE AN UNSETTLED WEATHER PATTERN TAKES SHAPE
LATER THIS WEEKEND AND INTO NEXT WEEK.
WE HAVE CONTINUED WITH A DRY FCST FOR THE FRI NIGHT AND SAT TIME
FRAME FOR NOW. WE WILL SEE WHAT IS LEFT OF THE WEAKENING COLD FRONT
TRYING TO MOVE THROUGH ON FRI SLIP SE OF THE AREA FRI EVENING. WE
CAN NOT RULE OUT A SHOWER DEVELOPING NEAR THIS FRONT...HOWEVER THE
CHC IS LOW ENOUGH TO LEAVE OUT OF THE FCST FOR THE TIME BEING. A
LACK OF MOISTURE WITH THE FRI FRONT WILL ONLY DIMINISH BY SAT AS THE
FRONT MOVES OUT. THERE IS NOT REALLY SIGNIFICANTLY COOLER AIR BEHIND
THIS...SO WE CONTINUE TO EXPECT HIGHS AROUND 80.
THE CHCS OF RAIN DOES GO UP ON SUN...AND WILL CONTINUE THROUGH THE
END OF THE PERIOD ON TUE. THE AREA WILL BE UNDER THE INFLUENCE OF
BROAD LONG WAVE TROUGHING CENTERED WELL NORTH IN CANADA. WE WILL SEE
THE JET CORE DROP A LITTLE FURTHER SOUTH WITH A TRAIN OF SHORT WAVES
HELPING THIS CAUSE. BEING CLOSER TO THE JET...WE WILL HAVE MORE OF
AN OPPORTUNITY FOR THE SHORT WAVES TO DIRECTLY IMPACT THE AREA. WE
WILL ALSO SEE THE LOW LEVEL FLOW BECOME A LITTLE MORE FAVORABLE TO
BRING SUFFICIENT MOISTURE TO THE AREA FOR RAIN. EXACT TIMING OF THE
SHORT WAVES WILL BE PROBLEMATIC AS IS USUAL IN A PATTERN LIKE THIS.
TEMPERATURES DO NOT LOOK TO BE TOO BAD IN THIS PATTERN. THE
UNSEASONABLY COOL AIR WILL REMAIN JUST NORTH OF THE STATE...NORTH OF
THE JET CORE. WE WILL SEE AVERAGE TO JUST SLIGHTLY BELOW AVERAGE
TEMPS DURING THIS PERIOD FOR OUR AREA. THIS EQUATES TO HIGHS
GENERALLY AROUND 80 AND LOWS AROUND 60.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 745 AM EDT WED JUL 29 2015
IT SHOULD REMAIN VFR FOR THE MOST PART TODAY DESPITE A COLD FRONT
WITH SCATTERED SHOWERS MOVING THROUGH. HOWEVER SOME BRIEF PERIODS
OF MVFR CONDITIONS ARE POSSIBLE WHERE/WHEN THE SHOWERS ARE
OCCURRING. THE BEST CHANCE OF TSTMS WILL BE FROM ABOUT 17Z TO 22Z
EAST OF A GRR-AZO LINE.
SKIES WILL CLEAR FROM WEST TO EAST AFTER 18Z WITH WINDS
INCREASING OUT OF THE WEST TO 12-22KTS. CLR SKIES AND WEST WINDS
OF 5-10 KTS ARE EXPECTED AFTER 00Z TONIGHT.
&&
.MARINE...
ISSUED AT 330 AM EDT WED JUL 29 2015
CONDITIONS MAY APPROACH SMALL CRAFT ADVISORY CRITERIA LATE TONIGHT
AND EARLY THURSDAY DUE TO STRONG WESTERLY FLOW BEHIND THE COLD
FRONT. THIS WILL NEED TO BE MONITORED. THIS SITUATION COULD ALSO
SUPPORT BEACH HAZARD STATEMENTS ESPECIALLY CONSIDERING THE CURRENT
WARM WATER TEMPERATURES AND OVERALL ATTRACTIVE BEACH CONDITIONS
SUPPORTIVE OF A HIGH BEACH POPULATION.
&&
.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.
&&
$$
UPDATE...04
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...MEADE
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1105 AM EDT WED JUL 29 2015
.UPDATE...
ISSUED AT 1054 AM EDT WED JUL 29 2015
ONE LONE RAIN SHOWER JUST NORTH OF BELLAIRE IN ANTRIM COUNTY.
STILL BELIEVE THAT THERE IS SOME INCREASED CHANCE FOR RAIN SHOWERS
AND PERHAPS A FEW THUNDERSTORMS ACROSS NE LOWER THIS AFTERNOON.
HEATING IS UNDERWAY WITH SFC BASED TEMPS ALREADY CLIMBING INTO
THE MIDDLE 80S WITH SFC TD`S AVERAGING IN THE MIDDLE 60S...ON THE
WAY TO CAPE VALUES DISCUSSED IN PREVIOUS UPDATE.
UPDATE ISSUED AT 805 AM EDT WED JUL 29 2015
IMPACT WEATHER: SCATTERED THUNDERSTORMS DEVELOPING THROUGH THE DAY.
SYNOPTIC PATTERN AND OBSERVATIONS:
MORNING ANALYSIS...LOW PRESSURE WAS PUSHING THROUGH WESTERN ONTARIO
WHILE DRAGGING A COLD FRONT ACROSS CENTRAL LAKE SUPERIOR...EASTERN
WISCONSIN AND ILLINOIS. SFC OBS...UPPER AIR AND HI-RES THETA-E
ANALYSIS SHOWING A WARM FRONT OUT AHEAD OF THE COLD FRONT...DRAPED
FROM CENTRAL LAKE MICHIGAN TO NRN INDIANA. THIS LEAVES A RATHER
NARROW "WARM SECTOR" THAT WAS PROGRESSING INTO THE REGION...WIDEST
THOUGH ACROSS THE SRN CWA. SCATTERED SHOWERS WERE SEEN ACROSS SRN WI
AND SRN LAKE MICHIGAN...IN THE WARM SECTOR...FORCED BY SOME UPPER
DIVERGENCE IN RIGHT ENTRANCE REGION OF 100+KT JET OVER MN. ALSO IN
PLAY...WEAK VORTICITY MAXIMA IN THE SRN END OF THE BETTER SW FLOW
ALOFT ACROSS THIS REGION. THERE WAS NOTHING ON THE FRONT NORTH OF
THIS FORCING. LAPSE RATES ALOFT WERE NOT TOO GOOD AT 5.0 C/KM AND THE
RESULTING CAPE WAS MINIMAL TO NONE AT THE MOMENT. WIND FIELDS ARE
ALSO PATHETIC RIGHT NOW...BUT STRONGER WINDS AND RESULTANT 0-6KM
BULK SHEAR OF 25-30KTS WAS ACROSS SRN WISCONSIN...GETTING A LITTLE
BETTER.
THROUGH THE DAY...AFOREMENTIONED WARM/COLD FRONTS LIFT INTO NRN
MICHIGAN..WITH WIDEST WARM SECTOR...BETTER PVA/VORTICITY AND
POSSIBLE WEAK UPPER DIVERGENCE (ALTHOUGH WE ARE REALLY IN A POOR
POSITION OF THE UPPER JET) TO SPREAD ACROSS THE SRN CWA. LAPSE RATES
IMPROVE LITTLE...MAXING OUT AT 5.5 C/KM...WHILE THE FRONT MAKES IT
TO NE LOWER EARLY TO MID AFTERNOON. THE SITUATION IS NOW PLAYING OUT
FOR WARMING/DESTABILIZATION THROUGH THE DAY TO DEVELOP SHOWERS AND
SCATTERED THUNDERSTORMS ALONG THE FRONT. THE MOST INSTABILITY WE
SEEM TO BE ABLE TO GENERATE WILL BE SOMEWHERE BETWEEN 200 J/KG IN
EASTERN UPPER...TO AS MUCH AS 700-800 J/KG SOUTH. THIS IS MORE THAN
LIKELY NOT GOING TO RESULT IN ANY CHANCE OF ORGANIZED STORMS/SEVERE
WEATHER....EVEN WITH INCREASING WINDS/0-6KM BULK SHEAR THROUGH THE
DAY.
DO BELIEVE THAT SHOWERS WILL SLOWLY INCREASE THROUGH THE MORNING
WITH THE CHANCE OF THUNDERSTORMS INCREASING ALONG/AHEAD OF THE FRONT
THROUGH THE LATE MORNING/EARLY AFTERNOON.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
PERSISTENT HIGH PRESSURE HAS SHIFTED EAST OF MICHIGAN EARLY THIS
MORNING AS A COLD FRONT APPROACHES FROM THE WEST. MID AND HIGH
CLOUDS HAVE BEGUN TO INCREASE ALONG THE NE PERIPHERY OF THE
CONVECTIVE CLOUD SHIELD GENERATED FROM THE MCS CURRENTLY IMPACTING
IOWA...NRN MISSOURI AND NRN ILLINOIS. THIS CONVECTION IS FUELED BY A
STRONG INSTABILITY AXIS (CAPES OF AROUND 3000 JOULES) AND 850 MB
THETA E RIDGING PUNCHING THRU THE MISSISSIPPI VALLEY ATTM. FURTHER
NORTH...OUR UPSTREAM RADARS SHOW A FEW SHOWERS AND EMBEDDED WEAK
STORMS TRYING TO DEVELOP JUST EAST OF THE ARROWHEAD OF MINNESOTA
OVER WRN LAKE SUPERIOR JUST AHEAD OF THE APPROACHING COLD FRONT.
CONVECTION IS STRUGGLING DUE TO WEAK INSTABILITY (500 JOULES OR
LESS) AND VERY LIMITED MOISTURE.
LATEST NAM12...RAP13 AND HRRR ALL SUGGEST THE FOCUS FOR MEANINGFUL
CONVECTIVE DEVELOPMENT WILL STAY SOUTH OF OUR CWA THRU TODAY WHERE
STRONGER INSTABILITY AND MUCH BETTER MOISTURE WILL RESIDE. NORTHERN
MICHIGAN IS ONCE AGAIN LOOKING AT THE PROSPECT THAT THE MAJORITY OF
OUR CWA MAY MISS OUT ON AN OPPORTUNITY FOR SOME MUCH NEEDED RAIN
TODAY. STILL...CHANCE POPS WILL REMAIN IN ORDER THRU THE DAY...WITH
THE EXPECTATION THAT A NARROW LINE OF SCATTERED SHOWERS WITH SOME
EMBEDDED THUNDERSTORMS WILL DEVELOP ALONG AND AHEAD OF THE COLD
FRONT. WILL MAKE SOME MINOR TIMING ADJUSTMENTS TO THIS BAND OF
PRECIP AS IT SLOWLY MOVES THRU OUR CWA TODAY...BUT WILL CERTAINLY
KEEP POPS IN THE CHANCE CATEGORY. NO REAL CHANCE FOR STRONG TO
SEVERE STORMS GIVEN LIMITED INSTABILITY AND MOISTURE AND
UNIMPRESSIVE WIND FIELDS AHEAD OF THE FRONT.
EXPECT ANOTHER VERY WARM DAY FOR NORTHERN MICHIGAN...BUT NOT AS WARM
AS IT HAS BEEN THE PAST FEW DAYS. HIGH TEMPS WILL WARM WELL INTO THE
80S...BUT SHOULD REFRAIN FROM REACHING INTO THE 90S. OVERNIGHT LOWS
WILL COOL BACK INTO THE 60S.
&&
.SHORT TERM...(THURSDAY THROUGH FRIDAY NIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
(7/30)THURSDAY...WITH THE FRONTAL PASSAGE TODAY, THE TEMPERATURES
FALL BACK TO NORMAL FOR THURSDAY. THERE ARE TWO CONCERNS FOR THE DAY
AND INTO THE NIGHT. 1) CLOUD COVER, ESPECIALLY NEAR ANJ. THE 850 MB
RH IS AROUND 90%, AND WITH THE 850 MB TEMPERATURES NEAR +10C, NEAR E
UPPER, IT COULD BE CLOUDIER. WHICH LEADS TO 2) TEMPERATURES COULD
END UP COOLER IF THERE ARE MORE CLOUDS IN E UPPER AND EVEN PARTS OF
THE N LOWER IF THE CLOUDS MAKE IT DOWN FAR ENOUGH SOUTH, BUT THAT
SEEMS ONLY TO ABOUT M-32 AT THE MOST.
SOUTH OF M-32, HOWEVER, THERE IS A DIFFERENT CONCERN, FIRE WEATHER.
WILL EXPECT THAT THE HIGH TEMPERATURES WILL REMAIN OVER 75F (CIPS
ANALOG GUIDANCE SHOWS 70% AT THE TEMPERATURES>75F). WINDS WILL BE
AROUND 15MPH AT THE 20FT LEVEL (SUSTAINED), WITH THE RH AROUND 30-
35%. AND WITH THE EXTENDED DRY PERIOD, WILL BE GOING WITH THE
ELEVATED FIRE DANGER.
(7/31)FRIDAY...THE DISCUSSION FOR THURSDAY COULD VERY WELL FIT FOR
FRIDAY AS WELL, EXCEPT THAT THERE IS A WEAK SFC LOW TRYING TO MOVE
INTO THE REGION AS THE 500 MB LOW SINKS A LITTLE MORE SOUTH AND
BEGINS TO COOL THINGS DOWN A BIT. AGAIN THE COOLEST, PROBABLY
CLOUDIEST AREA WILL BE NORTH OF M-32, WITH THE SOO DROPPING INTO THE
LOWER 70S FOR HIGHS POSSIBLY. LOOKS LIKE WE ARE STILL AROUND 80S
SOUTH OF M-32, AND WINDS WILL BE AGAIN BE CLOSE TO 15 MPH AT 20FT,
SO THERE IS AN ELEVATED FIRE DANGER RISK, ALTHOUGH THE RH MAY NOT BE
AS BAD THURSDAY. HOWEVER, IT WILL STILL BE AN ISSUE.
&&
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 331 AM EDT WED JUL 29 2015
WITH THE 500 MB LOW JUST NORTH OF JAMES BAY, WE GO BACK TO THE
PATTERN THAT WE`VE HAD OVER N MICHIGAN THE LAST 2 YEARS WITH
COOLER THAN NORMAL TEMPERATURES AND POSSIBLY SHOWERY CONDITIONS,
BUT NOTHING APPRECIABLE, AT LEAST FOR THE TIME BEING. CIPS ANALOGS
FALL RIGHT IN LINE WITH THE MEX NUMBERS AS WELL AS THE ECMWF
IDEAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY)
ISSUED AT 650 AM EDT WED JUL 29 2015
OVERALL CONDITIONS WILL REMAIN VFR AT ALL NRN LWR MICHIGAN TAF
SITES THRU WEDNESDAY NIGHT. A COLD FRONT WILL SWEEP THRU THE
REGION TODAY. LIMITED MOISTURE AND ONLY WEAK INSTABILITY ALONG AND
AHEAD OF THE FRONT WILL RESTRICT POPS TO ONLY CHANCE. EXPECT A
BAND OF SCATTERED SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS WILL
SLOWLY PUSH FROM WEST TO EAST THRU NRN LWR MICHIGAN THROUGHOUT
THE DAY. WILL CONTINUE TO HANDLE WITH VCSH IN THE TAFS FOR NOW.
SOUTH WINDS UNDER 10 KTS WILL SHIFT TO THE WEST IN THE WAKE OF THE
FRONT AND WILL INCREASE TO 10 TO 15 KTS...WITH A FEW HIGHER GUSTS
POSSIBLE.
&&
.MARINE...
ISSUED AT 1054 AM EDT WED JUL 29 2015
...BECOMING BREEZY THROUGH THE AFTERNOON...
A COLD FRONT IS CROSSING INTO NRN MICHIGAN LATE THIS MORNING WITH
DEEP DRY AIR AND GUSTY WESTERLY WINDS MAKING THEIR WAY EAST ACROSS
LAKE MICHIGAN. FEEL FAIRLY CONFIDENT IN THE DEVELOPMENT OF
ADVISORY LEVEL WINDS DEVELOPING OVER MOST OF THE NEARSHORE WATERS
THROUGH TONIGHT...AS SHALLOW COOLER AIR RESULTS IN NEAR NEUTRAL
STABILITY OVER THE LAKES. COULD BE DEALING WITH SOME CONTINUED
ADVISORY LEVEL GUSTS FOR LATER PERIODS...AS WINDS REMAIN WESTERLY.
LOOKING FOR SOME SCATTERED SHOWERS AND PERHAPS SOME THUNDERSTORMS
ALONG AND AHEAD OF THE COLD FRONT...FOR THE NE LOWER NEARSHORE
WATERS FOR THE EARLY AND MID AFTERNOON.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR LHZ345>347.
LM...SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR LMZ323-341-342-
344>346.
LS...SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR LSZ322.
&&
$$
UPDATE...SMD
NEAR TERM...MLR
SHORT TERM...JSL
LONG TERM...JSL
AVIATION...MLR
MARINE...SMD
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1045 AM EDT WED JUL 29 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 330 AM EDT WED JUL 29 2015
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A COLD
FRONT CROSSES THE REGION. GUSTY WESTERLY WINDS BEHIND THE FRONT WILL
USHER IN MORE COMFORTABLE LESS HUMID AIR FOR THE REMAINDER OF THE
WEEK ALTHOUGH HIGHS WILL REMAIN IN THE LOWER TO MID 80S.
&&
.UPDATE...
ISSUED AT 1044 AM EDT WED JUL 29 2015
DECREASED POPS A BIT BASED ON RADAR TRENDS. A WEAK COLD FRONT IS
MOVING ACROSS LAKE MICHIGAN ATTM AND MAY KICK OFF A STORM OR TWO
THIS AFTERNOON MAINLY ACROSS THE EASTERN CWA.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
ISOLATED SHOWERS HAVE DEVELOPED OVERNIGHT ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER AROUND TWO INCHES MOVING IN FROM THE
SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT. SUSPECT COVERAGE OF
SHOWERS WILL REMAIN RATHER LIMITED THIS MORNING ACROSS SW LWR MI AS
MORE EXPANSIVE AREA OF CONVECTION IMPACTS IOWA AND ILLINOIS.
OUR BEST PROSPECT FOR BETTER COVERAGE OF STORMS WILL BE THIS
AFTERNOON EAST OF HIGHWAY 131 WHERE SB CAPES NEAR 1500 J/KG ARE
PROGGED JUST AHEAD OF THE FRONT. RUC FCST SOUNDINGS EXHIBIT STEEP
LOW LEVEL LAPSE RATES WITH SFC TO 3 KM VALUES AROUND 8.5C NEAR
JXN. BASED ON THE HIGH PWAT VALUES OF UP TO 2.25 INCHES WE WILL
HAVE TO WATCH FOR THE POSSIBILITY OF SOME TORRENTIAL RAINFALL AND
POSSIBLY A LOCALIZED WET MICROBURST DAMAGING WIND EVENT.
CONVECTION ENDS FROM WEST TO EAST 18Z-22Z WITH THE PASSAGE OF THE
FRONT THEN DECREASING CLOUDS AND FALLING SFC DEW PTS EXPECTED.
BREEZY CONDITIONS LIKELY THURSDAY ONCE DEEPER MIXING COMMENCES.
SOME GUSTS TO 30 MPH WILL BE POSSIBLE IN THE AFTERNOON.
HAVE KEPT FRIDAY DRY FOR NOW ALTHOUGH SOME SMALL POPS MAY NEED TO
BE ADDED IN LATER FCSTS AS NEXT WEAK SFC FRONT/TROUGH DROPS SOUTH.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
THERE HAS NOT BEEN MUCH CHANGE OVER THE THE PAST FEW DAYS WITH
REGARD TO THE EXPECTED PATTERN. WE CONTINUE TO EXPECT LITTLE TO NO
RAIN THROUGH SAT...BEFORE AN UNSETTLED WEATHER PATTERN TAKES SHAPE
LATER THIS WEEKEND AND INTO NEXT WEEK.
WE HAVE CONTINUED WITH A DRY FCST FOR THE FRI NIGHT AND SAT TIME
FRAME FOR NOW. WE WILL SEE WHAT IS LEFT OF THE WEAKENING COLD FRONT
TRYING TO MOVE THROUGH ON FRI SLIP SE OF THE AREA FRI EVENING. WE
CAN NOT RULE OUT A SHOWER DEVELOPING NEAR THIS FRONT...HOWEVER THE
CHC IS LOW ENOUGH TO LEAVE OUT OF THE FCST FOR THE TIME BEING. A
LACK OF MOISTURE WITH THE FRI FRONT WILL ONLY DIMINISH BY SAT AS THE
FRONT MOVES OUT. THERE IS NOT REALLY SIGNIFICANTLY COOLER AIR BEHIND
THIS...SO WE CONTINUE TO EXPECT HIGHS AROUND 80.
THE CHCS OF RAIN DOES GO UP ON SUN...AND WILL CONTINUE THROUGH THE
END OF THE PERIOD ON TUE. THE AREA WILL BE UNDER THE INFLUENCE OF
BROAD LONG WAVE TROUGHING CENTERED WELL NORTH IN CANADA. WE WILL SEE
THE JET CORE DROP A LITTLE FURTHER SOUTH WITH A TRAIN OF SHORT WAVES
HELPING THIS CAUSE. BEING CLOSER TO THE JET...WE WILL HAVE MORE OF
AN OPPORTUNITY FOR THE SHORT WAVES TO DIRECTLY IMPACT THE AREA. WE
WILL ALSO SEE THE LOW LEVEL FLOW BECOME A LITTLE MORE FAVORABLE TO
BRING SUFFICIENT MOISTURE TO THE AREA FOR RAIN. EXACT TIMING OF THE
SHORT WAVES WILL BE PROBLEMATIC AS IS USUAL IN A PATTERN LIKE THIS.
TEMPERATURES DO NOT LOOK TO BE TOO BAD IN THIS PATTERN. THE
UNSEASONABLY COOL AIR WILL REMAIN JUST NORTH OF THE STATE...NORTH OF
THE JET CORE. WE WILL SEE AVERAGE TO JUST SLIGHTLY BELOW AVERAGE
TEMPS DURING THIS PERIOD FOR OUR AREA. THIS EQUATES TO HIGHS
GENERALLY AROUND 80 AND LOWS AROUND 60.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 745 AM EDT WED JUL 29 2015
IT SHOULD REMAIN VFR FOR THE MOST PART TODAY DESPITE A COLD FRONT
WITH SCATTERED SHOWERS MOVING THROUGH. HOWEVER SOME BRIEF PERIODS
OF MVFR CONDITIONS ARE POSSIBLE WHERE/WHEN THE SHOWERS ARE
OCCURRING. THE BEST CHANCE OF TSTMS WILL BE FROM ABOUT 17Z TO 22Z
EAST OF A GRR-AZO LINE.
SKIES WILL CLEAR FROM WEST TO EAST AFTER 18Z WITH WINDS
INCREASING OUT OF THE WEST TO 12-22KTS. CLR SKIES AND WEST WINDS
OF 5-10 KTS ARE EXPECTED AFTER 00Z TONIGHT.
&&
.MARINE...
ISSUED AT 330 AM EDT WED JUL 29 2015
CONDITIONS MAY APPROACH SMALL CRAFT ADVISORY CRITERIA LATE TONIGHT
AND EARLY THURSDAY DUE TO STRONG WESTERLY FLOW BEHIND THE COLD
FRONT. THIS WILL NEED TO BE MONITORED. THIS SITUATION COULD ALSO
SUPPORT BEACH HAZARD STATEMENTS ESPECIALLY CONSIDERING THE CURRENT
WARM WATER TEMPERATURES AND OVERALL ATTRACTIVE BEACH CONDITIONS
SUPPORTIVE OF A HIGH BEACH POPULATION.
&&
.HYDROLOGY...
ISSUED AT 1250 PM EDT TUE JUL 28 2015
RIVER LEVELS ARE FALLING AND WELL BELOW BANKFULL. WITH UNDER A
HALF INCH OF PRECIPITATION EXPECTED INTO NEXT WEEK... THESE
CONDITIONS SHOULD CONTINUE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...04
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...MEADE
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS GAYLORD MI
806 AM EDT WED JUL 29 2015
.UPDATE...
ISSUED AT 805 AM EDT WED JUL 29 2015
IMPACT WEATHER: SCATTERED THUNDERSTORMS DEVELOPING THROUGH THE DAY.
SYNOPTIC PATTERN AND OBSERVATIONS:
MORNING ANALYSIS...LOW PRESSURE WAS PUSHING THROUGH WESTERN ONTARIO
WHILE DRAGGING A COLD FRONT ACROSS CENTRAL LAKE SUPERIOR...EASTERN
WISCONSIN AND ILLINOIS. SFC OBS...UPPER AIR AND HI-RES THETA-E
ANALYSIS SHOWING A WARM FRONT OUT AHEAD OF THE COLD FRONT...DRAPED
FROM CENTRAL LAKE MICHIGAN TO NRN INDIANA. THIS LEAVES A RATHER
NARROW "WARM SECTOR" THAT WAS PROGRESSING INTO THE REGION...WIDEST
THOUGH ACROSS THE SRN CWA. SCATTERED SHOWERS WERE SEEN ACROSS SRN WI
AND SRN LAKE MICHIGAN...IN THE WARM SECTOR...FORCED BY SOME UPPER
DIVERGENCE IN RIGHT ENTRANCE REGION OF 100+KT JET OVER MN. ALSO IN
PLAY...WEAK VORTICITY MAXIMA IN THE SRN END OF THE BETTER SW FLOW
ALOFT ACROSS THIS REGION. THERE WAS NOTHING ON THE FRONT NORTH OF
THIS FORCING. LAPSE RATES ALOFT WERE NOT TOO GOOD AT 5.0 C/KM AND THE
RESULTING CAPE WAS MINIMAL TO NONE AT THE MOMENT. WIND FIELDS ARE
ALSO PATHETIC RIGHT NOW...BUT STRONGER WINDS AND RESULTANT 0-6KM
BULK SHEAR OF 25-30KTS WAS ACROSS SRN WISCONSIN...GETTING A LITTLE
BETTER.
THROUGH THE DAY...AFOREMENTIONED WARM/COLD FRONTS LIFT INTO NRN
MICHIGAN..WITH WIDEST WARM SECTOR...BETTER PVA/VORTICITY AND
POSSIBLE WEAK UPPER DIVERGENCE (ALTHOUGH WE ARE REALLY IN A POOR
POSITION OF THE UPPER JET) TO SPREAD ACROSS THE SRN CWA. LAPSE RATES
IMPROVE LITTLE...MAXING OUT AT 5.5 C/KM...WHILE THE FRONT MAKES IT
TO NE LOWER EARLY TO MID AFTERNOON. THE SITUATION IS NOW PLAYING OUT
FOR WARMING/DESTABILIZATION THROUGH THE DAY TO DEVELOP SHOWERS AND
SCATTERED THUNDERSTORMS ALONG THE FRONT. THE MOST INSTABILITY WE
SEEM TO BE ABLE TO GENERATE WILL BE SOMEWHERE BETWEEN 200 J/KG IN
EASTERN UPPER...TO AS MUCH AS 700-800 J/KG SOUTH. THIS IS MORE THAN
LIKELY NOT GOING TO RESULT IN ANY CHANCE OF ORGANIZED STORMS/SEVERE
WEATHER....EVEN WITH INCREASING WINDS/0-6KM BULK SHEAR THROUGH THE
DAY.
DO BELIEVE THAT SHOWERS WILL SLOWLY INCREASE THROUGH THE MORNING
WITH THE CHANCE OF THUNDERSTORMS INCREASING ALONG/AHEAD OF THE FRONT
THROUGH THE LATE MORNING/EARLY AFTERNOON.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
PERSISTENT HIGH PRESSURE HAS SHIFTED EAST OF MICHIGAN EARLY THIS
MORNING AS A COLD FRONT APPROACHES FROM THE WEST. MID AND HIGH
CLOUDS HAVE BEGUN TO INCREASE ALONG THE NE PERIPHERY OF THE
CONVECTIVE CLOUD SHIELD GENERATED FROM THE MCS CURRENTLY IMPACTING
IOWA...NRN MISSOURI AND NRN ILLINOIS. THIS CONVECTION IS FUELED BY A
STRONG INSTABILITY AXIS (CAPES OF AROUND 3000 JOULES) AND 850 MB
THETA E RIDGING PUNCHING THRU THE MISSISSIPPI VALLEY ATTM. FURTHER
NORTH...OUR UPSTREAM RADARS SHOW A FEW SHOWERS AND EMBEDDED WEAK
STORMS TRYING TO DEVELOP JUST EAST OF THE ARROWHEAD OF MINNESOTA
OVER WRN LAKE SUPERIOR JUST AHEAD OF THE APPROACHING COLD FRONT.
CONVECTION IS STRUGGLING DUE TO WEAK INSTABILITY (500 JOULES OR
LESS) AND VERY LIMITED MOISTURE.
LATEST NAM12...RAP13 AND HRRR ALL SUGGEST THE FOCUS FOR MEANINGFUL
CONVECTIVE DEVELOPMENT WILL STAY SOUTH OF OUR CWA THRU TODAY WHERE
STRONGER INSTABILITY AND MUCH BETTER MOISTURE WILL RESIDE. NORTHERN
MICHIGAN IS ONCE AGAIN LOOKING AT THE PROSPECT THAT THE MAJORITY OF
OUR CWA MAY MISS OUT ON AN OPPORTUNITY FOR SOME MUCH NEEDED RAIN
TODAY. STILL...CHANCE POPS WILL REMAIN IN ORDER THRU THE DAY...WITH
THE EXPECTATION THAT A NARROW LINE OF SCATTERED SHOWERS WITH SOME
EMBEDDED THUNDERSTORMS WILL DEVELOP ALONG AND AHEAD OF THE COLD
FRONT. WILL MAKE SOME MINOR TIMING ADJUSTMENTS TO THIS BAND OF
PRECIP AS IT SLOWLY MOVES THRU OUR CWA TODAY...BUT WILL CERTAINLY
KEEP POPS IN THE CHANCE CATEGORY. NO REAL CHANCE FOR STRONG TO
SEVERE STORMS GIVEN LIMITED INSTABILITY AND MOISTURE AND
UNIMPRESSIVE WIND FIELDS AHEAD OF THE FRONT.
EXPECT ANOTHER VERY WARM DAY FOR NORTHERN MICHIGAN...BUT NOT AS WARM
AS IT HAS BEEN THE PAST FEW DAYS. HIGH TEMPS WILL WARM WELL INTO THE
80S...BUT SHOULD REFRAIN FROM REACHING INTO THE 90S. OVERNIGHT LOWS
WILL COOL BACK INTO THE 60S.
&&
.SHORT TERM...(THURSDAY THROUGH FRIDAY NIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
(7/30)THURSDAY...WITH THE FRONTAL PASSAGE TODAY, THE TEMPERATURES
FALL BACK TO NORMAL FOR THURSDAY. THERE ARE TWO CONCERNS FOR THE DAY
AND INTO THE NIGHT. 1) CLOUD COVER, ESPECIALLY NEAR ANJ. THE 850 MB
RH IS AROUND 90%, AND WITH THE 850 MB TEMPERATURES NEAR +10C, NEAR E
UPPER, IT COULD BE CLOUDIER. WHICH LEADS TO 2) TEMPERATURES COULD
END UP COOLER IF THERE ARE MORE CLOUDS IN E UPPER AND EVEN PARTS OF
THE N LOWER IF THE CLOUDS MAKE IT DOWN FAR ENOUGH SOUTH, BUT THAT
SEEMS ONLY TO ABOUT M-32 AT THE MOST.
SOUTH OF M-32, HOWEVER, THERE IS A DIFFERENT CONCERN, FIRE WEATHER.
WILL EXPECT THAT THE HIGH TEMPERATURES WILL REMAIN OVER 75F (CIPS
ANALOG GUIDANCE SHOWS 70% AT THE TEMPERATURES>75F). WINDS WILL BE
AROUND 15MPH AT THE 20FT LEVEL (SUSTAINED), WITH THE RH AROUND 30-
35%. AND WITH THE EXTENDED DRY PERIOD, WILL BE GOING WITH THE
ELEVATED FIRE DANGER.
(7/31)FRIDAY...THE DISCUSSION FOR THURSDAY COULD VERY WELL FIT FOR
FRIDAY AS WELL, EXCEPT THAT THERE IS A WEAK SFC LOW TRYING TO MOVE
INTO THE REGION AS THE 500 MB LOW SINKS A LITTLE MORE SOUTH AND
BEGINS TO COOL THINGS DOWN A BIT. AGAIN THE COOLEST, PROBABLY
CLOUDIEST AREA WILL BE NORTH OF M-32, WITH THE SOO DROPPING INTO THE
LOWER 70S FOR HIGHS POSSIBLY. LOOKS LIKE WE ARE STILL AROUND 80S
SOUTH OF M-32, AND WINDS WILL BE AGAIN BE CLOSE TO 15 MPH AT 20FT,
SO THERE IS AN ELEVATED FIRE DANGER RISK, ALTHOUGH THE RH MAY NOT BE
AS BAD THURSDAY. HOWEVER, IT WILL STILL BE AN ISSUE.
&&
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 331 AM EDT WED JUL 29 2015
WITH THE 500 MB LOW JUST NORTH OF JAMES BAY, WE GO BACK TO THE
PATTERN THAT WE`VE HAD OVER N MICHIGAN THE LAST 2 YEARS WITH
COOLER THAN NORMAL TEMPERATURES AND POSSIBLY SHOWERY CONDITIONS,
BUT NOTHING APPRECIABLE, AT LEAST FOR THE TIME BEING. CIPS ANALOGS
FALL RIGHT IN LINE WITH THE MEX NUMBERS AS WELL AS THE ECMWF
IDEAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY)
ISSUED AT 650 AM EDT WED JUL 29 2015
OVERALL CONDITIONS WILL REMAIN VFR AT ALL NRN LWR MICHIGAN TAF
SITES THRU WEDNESDAY NIGHT. A COLD FRONT WILL SWEEP THRU THE
REGION TODAY. LIMITED MOISTURE AND ONLY WEAK INSTABILITY ALONG AND
AHEAD OF THE FRONT WILL RESTRICT POPS TO ONLY CHANCE. EXPECT A
BAND OF SCATTERED SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS WILL
SLOWLY PUSH FROM WEST TO EAST THRU NRN LWR MICHIGAN THROUGHOUT
THE DAY. WILL CONTINUE TO HANDLE WITH VCSH IN THE TAFS FOR NOW.
SOUTH WINDS UNDER 10 KTS WILL SHIFT TO THE WEST IN THE WAKE OF THE
FRONT AND WILL INCREASE TO 10 TO 15 KTS...WITH A FEW HIGHER GUSTS
POSSIBLE.
&&
.MARINE...
ISSUED AT 331 AM EDT WED JUL 29 2015
CHANCES OF SHOWERS AND STORMS WILL INCREASE FROM WEST TO EAST TODAY
AS A COLD FRONT SWINGS THROUGH NORTHERN MICHIGAN. WINDS AND WAVES
WILL APPROACH SCA CRITERIA THIS AFTERNOON AND THIS EVENING AS WINDS
SHIFT TO THE WEST AND STRENGTHEN BEHIND THE COLD FRONT. AT THIS
POINT...EXPECT CONDITIONS WILL FALL JUST SHORT OF CRITERIA.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...SMD
NEAR TERM...MLR
SHORT TERM...JSL
LONG TERM...JSL
AVIATION...MLR
MARINE...MLR
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
746 AM EDT WED JUL 29 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EDT WED JUL 29 2015
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A COLD
FRONT CROSSES THE REGION. GUSTY WESTERLY WINDS BEHIND THE FRONT WILL
USHER IN MORE COMFORTABLE LESS HUMID AIR FOR THE REMAINDER OF THE
WEEK ALTHOUGH HIGHS WILL REMAIN IN THE LOWER TO MID 80S.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
ISOLATED SHOWERS HAVE DEVELOPED OVERNIGHT ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER AROUND TWO INCHES MOVING IN FROM THE
SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT. SUSPECT COVERAGE OF
SHOWERS WILL REMAIN RATHER LIMITED THIS MORNING ACROSS SW LWR MI AS
MORE EXPANSIVE AREA OF CONVECTION IMPACTS IOWA AND ILLINOIS.
OUR BEST PROSPECT FOR BETTER COVERAGE OF STORMS WILL BE THIS
AFTERNOON EAST OF HIGHWAY 131 WHERE SB CAPES NEAR 1500 J/KG ARE
PROGGED JUST AHEAD OF THE FRONT. RUC FCST SOUNDINGS EXHIBIT STEEP
LOW LEVEL LAPSE RATES WITH SFC TO 3 KM VALUES AROUND 8.5C NEAR
JXN. BASED ON THE HIGH PWAT VALUES OF UP TO 2.25 INCHES WE WILL
HAVE TO WATCH FOR THE POSSIBILITY OF SOME TORRENTIAL RAINFALL AND
POSSIBLY A LOCALIZED WET MICROBURST DAMAGING WIND EVENT.
CONVECTION ENDS FROM WEST TO EAST 18Z-22Z WITH THE PASSAGE OF THE
FRONT THEN DECREASING CLOUDS AND FALLING SFC DEW PTS EXPECTED.
BREEZY CONDITIONS LIKELY THURSDAY ONCE DEEPER MIXING COMMENCES.
SOME GUSTS TO 30 MPH WILL BE POSSIBLE IN THE AFTERNOON.
HAVE KEPT FRIDAY DRY FOR NOW ALTHOUGH SOME SMALL POPS MAY NEED TO
BE ADDED IN LATER FCSTS AS NEXT WEAK SFC FRONT/TROUGH DROPS SOUTH.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
THERE HAS NOT BEEN MUCH CHANGE OVER THE THE PAST FEW DAYS WITH
REGARD TO THE EXPECTED PATTERN. WE CONTINUE TO EXPECT LITTLE TO NO
RAIN THROUGH SAT...BEFORE AN UNSETTLED WEATHER PATTERN TAKES SHAPE
LATER THIS WEEKEND AND INTO NEXT WEEK.
WE HAVE CONTINUED WITH A DRY FCST FOR THE FRI NIGHT AND SAT TIME
FRAME FOR NOW. WE WILL SEE WHAT IS LEFT OF THE WEAKENING COLD FRONT
TRYING TO MOVE THROUGH ON FRI SLIP SE OF THE AREA FRI EVENING. WE
CAN NOT RULE OUT A SHOWER DEVELOPING NEAR THIS FRONT...HOWEVER THE
CHC IS LOW ENOUGH TO LEAVE OUT OF THE FCST FOR THE TIME BEING. A
LACK OF MOISTURE WITH THE FRI FRONT WILL ONLY DIMINISH BY SAT AS THE
FRONT MOVES OUT. THERE IS NOT REALLY SIGNIFICANTLY COOLER AIR BEHIND
THIS...SO WE CONTINUE TO EXPECT HIGHS AROUND 80.
THE CHCS OF RAIN DOES GO UP ON SUN...AND WILL CONTINUE THROUGH THE
END OF THE PERIOD ON TUE. THE AREA WILL BE UNDER THE INFLUENCE OF
BROAD LONG WAVE TROUGHING CENTERED WELL NORTH IN CANADA. WE WILL SEE
THE JET CORE DROP A LITTLE FURTHER SOUTH WITH A TRAIN OF SHORT WAVES
HELPING THIS CAUSE. BEING CLOSER TO THE JET...WE WILL HAVE MORE OF
AN OPPORTUNITY FOR THE SHORT WAVES TO DIRECTLY IMPACT THE AREA. WE
WILL ALSO SEE THE LOW LEVEL FLOW BECOME A LITTLE MORE FAVORABLE TO
BRING SUFFICIENT MOISTURE TO THE AREA FOR RAIN. EXACT TIMING OF THE
SHORT WAVES WILL BE PROBLEMATIC AS IS USUAL IN A PATTERN LIKE THIS.
TEMPERATURES DO NOT LOOK TO BE TOO BAD IN THIS PATTERN. THE
UNSEASONABLY COOL AIR WILL REMAIN JUST NORTH OF THE STATE...NORTH OF
THE JET CORE. WE WILL SEE AVERAGE TO JUST SLIGHTLY BELOW AVERAGE
TEMPS DURING THIS PERIOD FOR OUR AREA. THIS EQUATES TO HIGHS
GENERALLY AROUND 80 AND LOWS AROUND 60.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
ISOLATED SHOWERS HAVE DEVELOPED OVERNIGHT ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER AROUND TWO INCHES MOVING IN FROM THE
SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT. SUSPECT COVERAGE OF
SHOWERS WILL REMAIN RATHER LIMITED THIS MORNING ACROSS SW LWR MI AS
MORE EXPANSIVE AREA OF CONVECTION IMPACTS IOWA AND ILLINOIS.
OUR BEST PROSPECTS FOR BETTER COVERAGE OF STORMS WILL BE THIS
AFTERNOON EAST OF HIGHWAY 131 WHERE SB CAPES NEAR 1500 J/KG ARE
PROGGED JUST AHEAD OF THE FRONT. RUC FCST SNDGS EXHIBIT STEEP LOW
LEVEL LAPSE RATES WITH SFC TO 3 KM AROUND 8.5C NEAR JXN. BASED ON
THE HIGH PWAT VALUES OF UP TO 2.25 INCHES WE WILL HAVE TO WATCH OF
THE POSSIBILITY OF SOME TORRENTIAL RAINFALL AND POSSIBLY A LOCALIZED
WET MICROBURST DAMAGING WIND EVENT.
CONVECTION ENDS FROM WEST TO EAST 18Z-22Z WITH THE PASSAGE OF THE
FRONT THEN DECREASING CLOUDS AND FALLING SFC DEW PTS EXPECTED.
BREEZY CONDITIONS EXPECTED THURSDAY ONCE DEEPER MIXING COMMENCES.
SOME GUSTS TO 30 MPH WILL BE POSSIBLE IN THE AFTERNOON.
HAVE KEPT FRIDAY DRY FOR NOW ALTHOUGH SOME SMALL POPS MAY NEED TO BE
ADDED IN LATER FCSTS AS NEXT WEAK FRONT/TROUGH DROPS SOUTH.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
THERE HAS NOT BEEN MUCH CHANGE OVER THE THE PAST FEW DAYS WITH
REGARD TO THE EXPECTED PATTERN. WE CONTINUE TO EXPECT LITTLE TO NO
RAIN THROUGH SAT...BEFORE AN UNSETTLED WEATHER PATTERN TAKES SHAPE
LATER THIS WEEKEND AND INTO NEXT WEEK.
WE HAVE CONTINUED WITH A DRY FCST FOR THE FRI NIGHT AND SAT TIME
FRAME FOR NOW. WE WILL SEE WHAT IS LEFT OF THE WEAKENING COLD FRONT
TRYING TO MOVE THROUGH ON FRI SLIP SE OF THE AREA FRI EVENING. WE
CAN NOT RULE OUT A SHOWER DEVELOPING NEAR THIS FRONT...HOWEVER THE
CHC IS LOW ENOUGH TO LEAVE OUT OF THE FCST FOR THE TIME BEING. A
LACK OF MOISTURE WITH THE FRI FRONT WILL ONLY DIMINISH BY SAT AS THE
FRONT MOVES OUT. THERE IS NOT REALLY SIGNIFICANTLY COOLER AIR BEHIND
THIS...SO WE CONTINUE TO EXPECT HIGHS AROUND 80.
THE CHCS OF RAIN DOES GO UP ON SUN...AND WILL CONTINUE THROUGH THE
END OF THE PERIOD ON TUE. THE AREA WILL BE UNDER THE INFLUENCE OF
BROAD LONG WAVE TROUGHING CENTERED WELL NORTH IN CANADA. WE WILL SEE
THE JET CORE DROP A LITTLE FURTHER SOUTH WITH A TRAIN OF SHORT WAVES
HELPING THIS CAUSE. BEING CLOSER TO THE JET...WE WILL HAVE MORE OF
AN OPPORTUNITY FOR THE SHORT WAVES TO DIRECTLY IMPACT THE AREA. WE
WILL ALSO SEE THE LOW LEVEL FLOW BECOME A LITTLE MORE FAVORABLE TO
BRING SUFFICIENT MOISTURE TO THE AREA FOR RAIN. EXACT TIMING OF THE
SHORT WAVES WILL BE PROBLEMATIC AS IS USUAL IN A PATTERN LIKE THIS.
TEMPERATURES DO NOT LOOK TO BE TOO BAD IN THIS PATTERN. THE
UNSEASONABLY COOL AIR WILL REMAIN JUST NORTH OF THE STATE...NORTH OF
THE JET CORE. WE WILL SEE AVERAGE TO JUST SLIGHTLY BELOW AVERAGE
TEMPS DURING THIS PERIOD FOR OUR AREA. THIS EQUATES TO HIGHS
GENERALLY AROUND 80 AND LOWS AROUND 60.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 745 AM EDT WED JUL 29 2015
IT SHOULD REMAIN VFR FOR THE MOST PART TODAY DESPITE A COLD FRONT
WITH SCATTERED SHOWERS MOVING THROUGH. HOWEVER SOME BRIEF PERIODS
OF MVFR CONDITIONS ARE POSSIBLE WHERE/WHEN THE SHOWERS ARE
OCCURRING. THE BEST CHANCE OF TSTMS WILL BE FROM ABOUT 17Z TO 22Z
EAST OF A GRR-AZO LINE.
SKIES WILL CLEAR FROM WEST TO EAST AFTER 18Z WITH WINDS
INCREASING OUT OF THE WEST TO 12-22KTS. CLR SKIES AND WEST WINDS
OF 5-10 KTS ARE EXPECTED AFTER 00Z TONIGHT.
&&
.MARINE...
ISSUED AT 330 AM EDT WED JUL 29 2015
CONDITIONS MAY APPROACH SMALL CRAFT ADVISORY CRITERIA LATE TONIGHT
AND EARLY THURSDAY DUE TO STRONG WESTERLY FLOW BEHIND THE COLD
FRONT. THIS WILL NEED TO BE MONITORED. THIS SITUATION COULD ALSO
SUPPORT BEACH HAZARD STATEMENTS ESPECIALLY CONSIDERING THE CURRENT
WARM WATER TEMPERATURES AND OVERALL ATTRACTIVE BEACH CONDITIONS
SUPPORTIVE OF A HIGH BEACH POPULATION.
&&
.HYDROLOGY...
ISSUED AT 1250 PM EDT TUE JUL 28 2015
RIVER LEVELS ARE FALLING AND WELL BELOW BANKFULL. WITH UNDER A
HALF INCH OF PRECIPITATION EXPECTED INTO NEXT WEEK... THESE
CONDITIONS SHOULD CONTINUE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...MEADE
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
721 AM EDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EDT WED JUL 29 2015
FAIRLY IMPRESSIVE SURFACE AND UPPER LOW FOR LATE JULY IS LOCATED
JUST TO THE SOUTH OF LAKE WINNIPEG EARLY THIS MORNING...AND IT IS
KEEPING MUCH OF ITS ENERGY NEAR THE LOW IN MANITOBA. THIS HAS LED TO
A FAIRLY UNEVENTFUL PASSAGE OF THE COLD FRONT DUE TO THE LACK OF ANY
UPPER LEVEL SUPPORT/SHORTWAVES MOVING THROUGH THE AREA AND THE MID-
LEVEL DRY AIR AND CAPPING SEEN ON RAP ANALYSIS SOUNDINGS. THERE WAS
A THUNDERSTORM THAT MOVED NORTHEAST OUT OF NORTHWEST WISCONSIN
EARLIER IN THE NIGHT BUT DISSIPATED OVER WESTERN LAKE SUPERIOR. HAVE
SEEN SOME LIGHT SHOWER DEVELOPMENT OVER THE WESTERN U.P. OVER THE
LAST 1-2HRS AND THEY ARE MOVING NORTHEAST WHILE THE FRONT SHIFTS
THEM TO THE EAST. THERE HASN/T BEEN ANY LIGHTNING NOTED WITH THEM
THUS FAR...LARGELY DUE TO THEM STRUGGLING TO GET ABOVE THE FREEZING
LEVEL (HAVE PEAKED AROUND 15KFT). STILL THINK SOME THUNDER IS
POSSIBLE AS THEY ALIGN WITH A THIN AREA OF 500 J/KG OF MUCAPE AHEAD
OF THE FRONT AS SEEN ON THE SPC MESOSCALE ANALYSIS PAGE. THE COLD
FRONT WILL CONTINUE TO THE EAST THIS MORNING AND EXIT THE AREA BY
NOON. WILL CONTINUE TO SHOW SLIGHT CHANCE POPS RIGHT ALONG THE FRONT
AS IT MOVES EAST THIS MORNING...BUT DON/T EXPECT ANYTHING MORE THAN
AN ISOLATED SHOWER/THUNDERSTORM. HAVE SEEN A FAIRLY SIGNIFICANT DROP
IN DEWPOINTS BEHIND THE FRONT...AS KIWD WENT FROM A 72 DEGREE
DEWPOINT AT 535Z AND QUICKLY DROPPED TO 64 AT 615Z AND IS NOW AT 57
AT 735Z.
BEHIND THE FRONT...THE DRY SLOT SEEN ON WATER VAPOR IMAGERY WILL
MOVE THROUGH THE AREA AND LEAD TO AN AREA OF MOSTLY SUNNY START TO
THE DAY OVER THE WEST. DO EXPECT THE AREA OF CLOUDS IN NORTHEAST ND
AND NORTHWEST MN TO MOVE EAST INTO THE WESTERN CWA THIS AFTERNOON
AND BE AIDED BY DIURNAL HEATING TO PRODUCE DIURNAL CU ON THE LEADING
EDGE AND AHEAD OF THE CLOUDS INTO THE CENTRAL U.P. OVER THE
EAST...AFTER A CLOUDY START TO THE DAY...EXPECT A PERIOD OF MOSTLY
SUNNY SKIES AND THEN SOME DIURNAL CU IN AFTERNOON AND LINGERING INTO
THE EVENING. HIGHS TODAY WILL BE IN THE UPPER 70S OVER THE WEST AND
THE LOW-MID 80S OVER THE CENTRAL AND EAST.
THE MAIN HAZARD BEHIND THE FRONT WILL BE THE GUSTY WEST-SOUTHWEST
WINDS. THESE WINDS WILL BE AIDED BY THE TIGHT PRESSURE GRADIENT OVER
THE NORTHWEST HALF OF THE CWA AND LARGELY OVER NORTHWESTERN LAKE
SUPERIOR. HAVE ALREADY SEEN GUSTS TO 20-25KTS IMMEDIATELY BEHIND THE
FRONT EARLIER IN THE NIGHT AND CLOSER TO THE LOW WINDS HAVE BEEN
GUSTING TO 30-35KTS IN NORTHWEST MINNESOTA. THE AMPLE SUNSHINE THIS
MORNING WILL HELP TO MIX INTO THE 25-40KT WINDS AROUND 925MB TO THE
SURFACE...WITH THE STRONGEST WINDS OVER THE KEWEENAW PENINSULA. IN
THAT AREA...WOULD EXPECT GUSTS TO AROUND 35KTS BY MID AFTERNOON AND
THERE COULD BE A BRIEF PERIOD OF GUSTS TO 40KTS BY EARLY EVENING.
DON/T THINK THERE WILL BE A LONG ENOUGH PERIOD FOR A WIND ADVISORY
FOR THE KEWEENAW PENINSULA (NEED 39KTS)...SO WILL ISSUE AN SPS FOR
KEWEENAW AND NORTHERN HOUGHTON COUNTIES TO HIGHLIGHT THE WINDY
CONDITIONS FOR TODAY. THE REST OF THE U.P. WILL SEE WIND GUSTS OF 20-
30KTS...HIGHEST OVER THE WEST.
WITH THE MUCH DRIER AIR MOVING INTO THE AREA...THINK DEWPOINTS WILL
MIX OUT INTO THE UPPER 40S TO AROUND 50 OVER THE WEST/CENTRAL TODAY.
WHILE TEMPERATURES WILL BE COOLER THAN YESTERDAY...RH VALUES WILL
STILL FALL INTO THE 30S. THAT WILL LEAD TO AN ELEVATED RISK OF
WILDFIRES ACROSS MUCH OF THE U.P. TODAY. SINCE THE RH VALUES WILL BE
ABOVE RED FLAG CRITERIA...THIS SITUATION WOULD FALL UNDER AN RFD
PRODUCT DUE TO THE FREQUENT GUSTS OVER 25 MPH. SINCE COORDINATION
NEEDS TO BE DONE WITH FIRE WX USERS BEFORE ISSUANCE...WILL PASS
ALONG TO DAY SHIFT TO COORDINATE POTENTIAL ISSUANCE.
A SECONDARY TROUGH MOVES EAST ACROSS THE AREA TONIGHT. SOME CLOUDS
ASSOCIATED WITH IT...LARGELY OVER LAKE SUPERIOR...BUT NOT EXPECTING
ANY RAIN. THERE WILL STILL BE STRONG WINDS JUST ABOVE THE SURFACE
AGAIN TONIGHT...WHICH WILL HELP TO KEEP THE WINDS FROM DECOUPLING.
HAVE KEPT UP GUSTS OVER THE KEWEENAW PENINSULA (TO 20-30KTS)
...ESPECIALLY FOR THE EXPOSED LOCATIONS. OTHERWISE...THE REST OF THE
AREA WILL SEE WINDS TURNING WESTERLY WITH GUSTS TO 10-20KTS (HIGHEST
NORTH).
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 455 AM EDT WED JUL 29 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA AND A BROAD RIDGE IS
ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE FEATURES A NW
FLOW WILL DOMINATE THE GREAT LAKES REGION AS A SERIES OF MAINLY WEAK
SHORTWAVES PASSING THRU BRING CHCS FOR PERIODIC LIGHT SHOWERS.
TIMING OF THESE WEAK SHORTWAVES WILL LIKELY BE 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
TREND BELOW NORMAL TOWARD THE BEGINNING HALF OF NEXT WEEK AS A MID-
LVL TROUGH BEGINS TO AMPLIFY INTO THE UPPER GREAT LAKES REGION.
THU THROUGH FRI...MOST OF MODELS SHOW A WEAK SHORTWAVE MOVING
THROUGH THE AREA TOWARD THU EVENING WITH ANOTHER WEAK SHORTWAVE
MOVING THROUGH DURING THE DAY ON FRI. WITH SEVERAL OF THE MODELS
SHOWING A FEW HUNDRED J/KG OF MLCAPE EACH DAY MAINLY DURING THE
AFTERNOON/EVENING HRS WILL PROBABLY NEED TO MAINTAIN SLIGHT CHC POPS
EACH DAY FOR ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW
EXPECT ANY PCPN FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
FRI NIGHT AND SAT...ANOTHER SHORTWAVE MOVING THROUGH DURING THIS
TIME WILL WARRANT HAVING SLIGHT CHC POPS OVER MAINLY THE NW AND NE
CWA INCLUDING LAKE SUPERIOR.
TEMPERATURES THU THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS HAVE TRENDED FARTHER NORTH WITH MORE SIGNIFICANT SHORTWAVE
DUE TO MOVE IN SAT NIGHT INTO SUN SO HAVE BACKED OFF TO ONLY SLIGHT
CHANCE POPS FOR THAT TIME FRAME. BEST LIFT WITH SHORTWAVE STAYS
NORTH AND BETTER INSTABILITY AS INDICATED BY MODELS IS FARTHER
SOUTH.
TIMING OF SHORTWAVE AND ASSOC COLD FRONT FOR EARLY NEXT WEEK
DIFFERS BTWN THE 00Z GFS AND 00Z ECMWF. THE ECMWF IS QUICKER
BRINGING SYSTEM THROUGH SUN NIGHT INTO MON WHILE THE GFS DOESN/T
BRING SYSTEM THRU UNTIL LATE MON INTO MON NIGHT. THIS SYSTEM MAY
HAVE A BETTER CHC OF BRINGING MORE WIDESPREAD...ALTHOUGH LIGHT
PCPN...BUT GIVEN UNCERTAINTY IN TIMING AT THIS POINT DON/T HAVE
ANYTHING MORE THAN LOW CHC POPS. MODELS ADVERTISE TEMPS COOLING BELOW
NORMAL TEMPS BEHIND THE FRONTAL SYSTEM ESPECIALLY BY TUE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 717 AM EDT WED JUL 29 2015
A COLD FRONT HAS PASSED THROUGH ALL THREE TAF SITES EARLY THIS
MORNING. GUSTY WEST-SOUTHWEST WINDS ARE EXPECTED AT ALL THREE SITES
TODAY...WITH THE HIGHEST GUSTS (TO AROUND 35KTS) EXPECTED AT KCMX.
THE WINDS WILL DIMINISH SOME AT ALL THREE SITES TONIGHT...BUT STILL
EXPECT GUSTS TO 25KTS AT KCMX. AS FOR CLOUDS...CLEARING THIS
MORNING WILL GIVE WAY TO AN AREA OF VFR CLOUDS MOVING IN FROM
NORTHERN MINNESOTA...ALONG WITH SOME DIURNAL CU AT KSAW.
FEW-SCATTERED VFR CLOUDS WILL REMAIN INTO TONIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EDT WED JUL 29 2015
A STRONG LOW PRESSURE SYSTEM FOR LATE JULY IS LOCATED NEAR LAKE
WINNIPEG EARLY THIS MORNING AND IT WILL LIFT NORTHEAST INTO FAR
NORTHERN ONTARIO TODAY. MEANWHILE...IT WILL SWEEP A COLD FRONT
CURRENTLY OVER CENTRAL LAKE SUPERIOR EAST ACROSS THE REST OF THE
LAKE THIS MORNING. BEHIND THE FRONT...SOUTHWEST WINDS WILL
INCREASE THROUGH THE MORNING OVER THE WESTERN HALF OF THE LAKE AND
PRODUCE GALES TO 35-40KTS. THERE COULD BE A FEW GUSTS IN THE 40-45KT
RANGE TOWARDS ISLE ROYALE THIS AFTERNOON. THESE WINDS WILL DECREASE
AND SHIFT TO THE WEST THIS EVENING AS THE FIRST IN A SERIES OF
TROUGHS MOVE ACROSS LAKE SUPERIOR THROUGH SUNDAY MORNING (ASSOCIATED
WITH THE SURFACE LOW SLOWLY DRIFTING OVER HUDSON BAY). THERE IS THE
POTENTIAL FOR GALES OUT OF THE WEST-NORTHWEST TONIGHT BEHIND THE
SECONDARY TROUGH AS THE PRESSURE GRADIENT REMAINS TIGHT OVER
NORTHERN LAKE SUPERIOR. BUT EXPECT THE MARINE LAYER TO BE THE
STRONGEST IN THAT AREA WITH THE WATER TEMPERATURES STILL IN THE
UPPER 30S AND LOWER 40S. WILL ADD A MENTION OF GALE FORCE GUSTS FOR
NOW. THE PRESSURE GRADIENT WILL GRADUALLY DECREASE THROUGH THE REST
OF THE WEAK AS ADDITIONAL WEAK SURFACE TROUGHS MOVE SOUTHEAST ACROSS
THE LAKE. EXPECT WINDS TO STAY BELOW 25KTS AFTER THURSDAY AND
THROUGH THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 8 PM EDT /7 PM CDT/ THIS EVENING FOR LSZ162-
240>242-263.
GALE WARNING FROM 11 AM THIS MORNING TO 11 PM EDT THIS EVENING
FOR LSZ264.
GALE WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING
FOR LSZ245>247.
GALE WARNING FROM 11 AM THIS MORNING TO 10 PM EDT THIS EVENING
FOR LSZ243-244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
650 AM EDT WED JUL 29 2015
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
PERSISTENT HIGH PRESSURE HAS SHIFTED EAST OF MICHIGAN EARLY THIS
MORNING AS A COLD FRONT APPROACHES FROM THE WEST. MID AND HIGH
CLOUDS HAVE BEGUN TO INCREASE ALONG THE NE PERIPHERY OF THE
CONVECTIVE CLOUD SHIELD GENERATED FROM THE MCS CURRENTLY IMPACTING
IOWA...NRN MISSOURI AND NRN ILLINOIS. THIS CONVECTION IS FUELED BY A
STRONG INSTABILITY AXIS (CAPES OF AROUND 3000 JOULES) AND 850 MB
THETA E RIDGING PUNCHING THRU THE MISSISSIPPI VALLEY ATTM. FURTHER
NORTH...OUR UPSTREAM RADARS SHOW A FEW SHOWERS AND EMBEDDED WEAK
STORMS TRYING TO DEVELOP JUST EAST OF THE ARROWHEAD OF MINNESOTA
OVER WRN LAKE SUPERIOR JUST AHEAD OF THE APPROACHING COLD FRONT.
CONVECTION IS STRUGGLING DUE TO WEAK INSTABILITY (500 JOULES OR
LESS) AND VERY LIMITED MOISTURE.
LATEST NAM12...RAP13 AND HRRR ALL SUGGEST THE FOCUS FOR MEANINGFUL
CONVECTIVE DEVELOPMENT WILL STAY SOUTH OF OUR CWA THRU TODAY WHERE
STRONGER INSTABILITY AND MUCH BETTER MOISTURE WILL RESIDE. NORTHERN
MICHIGAN IS ONCE AGAIN LOOKING AT THE PROSPECT THAT THE MAJORITY OF
OUR CWA MAY MISS OUT ON AN OPPORTUNITY FOR SOME MUCH NEEDED RAIN
TODAY. STILL...CHANCE POPS WILL REMAIN IN ORDER THRU THE DAY...WITH
THE EXPECTATION THAT A NARROW LINE OF SCATTERED SHOWERS WITH SOME
EMBEDDED THUNDERSTORMS WILL DEVELOP ALONG AND AHEAD OF THE COLD
FRONT. WILL MAKE SOME MINOR TIMING ADJUSTMENTS TO THIS BAND OF
PRECIP AS IT SLOWLY MOVES THRU OUR CWA TODAY...BUT WILL CERTAINLY
KEEP POPS IN THE CHANCE CATEGORY. NO REAL CHANCE FOR STRONG TO
SEVERE STORMS GIVEN LIMITED INSTABILITY AND MOISTURE AND
UNIMPRESSIVE WIND FIELDS AHEAD OF THE FRONT.
EXPECT ANOTHER VERY WARM DAY FOR NORTHERN MICHIGAN...BUT NOT AS WARM
AS IT HAS BEEN THE PAST FEW DAYS. HIGH TEMPS WILL WARM WELL INTO THE
80S...BUT SHOULD REFRAIN FROM REACHING INTO THE 90S. OVERNIGHT LOWS
WILL COOL BACK INTO THE 60S.
&&
.SHORT TERM...(THURSDAY THROUGH FRIDAY NIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
(7/30)THURSDAY...WITH THE FRONTAL PASSAGE TODAY, THE TEMPERATURES
FALL BACK TO NORMAL FOR THURSDAY. THERE ARE TWO CONCERNS FOR THE DAY
AND INTO THE NIGHT. 1) CLOUD COVER, ESPECIALLY NEAR ANJ. THE 850 MB
RH IS AROUND 90%, AND WITH THE 850 MB TEMPERATURES NEAR +10C, NEAR E
UPPER, IT COULD BE CLOUDIER. WHICH LEADS TO 2) TEMPERATURES COULD
END UP COOLER IF THERE ARE MORE CLOUDS IN E UPPER AND EVEN PARTS OF
THE N LOWER IF THE CLOUDS MAKE IT DOWN FAR ENOUGH SOUTH, BUT THAT
SEEMS ONLY TO ABOUT M-32 AT THE MOST.
SOUTH OF M-32, HOWEVER, THERE IS A DIFFERENT CONCERN, FIRE WEATHER.
WILL EXPECT THAT THE HIGH TEMPERATURES WILL REMAIN OVER 75F (CIPS
ANALOG GUIDANCE SHOWS 70% AT THE TEMPERATURES>75F). WINDS WILL BE
AROUND 15MPH AT THE 20FT LEVEL (SUSTAINED), WITH THE RH AROUND 30-
35%. AND WITH THE EXTENDED DRY PERIOD, WILL BE GOING WITH THE
ELEVATED FIRE DANGER.
(7/31)FRIDAY...THE DISCUSSION FOR THURSDAY COULD VERY WELL FIT FOR
FRIDAY AS WELL, EXCEPT THAT THERE IS A WEAK SFC LOW TRYING TO MOVE
INTO THE REGION AS THE 500 MB LOW SINKS A LITTLE MORE SOUTH AND
BEGINS TO COOL THINGS DOWN A BIT. AGAIN THE COOLEST, PROBABLY
CLOUDIEST AREA WILL BE NORTH OF M-32, WITH THE SOO DROPPING INTO THE
LOWER 70S FOR HIGHS POSSIBLY. LOOKS LIKE WE ARE STILL AROUND 80S
SOUTH OF M-32, AND WINDS WILL BE AGAIN BE CLOSE TO 15 MPH AT 20FT,
SO THERE IS AN ELEVATED FIRE DANGER RISK, ALTHOUGH THE RH MAY NOT BE
AS BAD THURSDAY. HOWEVER, IT WILL STILL BE AN ISSUE.
&&
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 331 AM EDT WED JUL 29 2015
WITH THE 500 MB LOW JUST NORTH OF JAMES BAY, WE GO BACK TO THE
PATTERN THAT WE`VE HAD OVER N MICHIGAN THE LAST 2 YEARS WITH
COOLER THAN NORMAL TEMPERATURES AND POSSIBLY SHOWERY CONDITIONS,
BUT NOTHING APPRECIABLE, AT LEAST FOR THE TIME BEING. CIPS ANALOGS
FALL RIGHT IN LINE WITH THE MEX NUMBERS AS WELL AS THE ECMWF
IDEAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY)
ISSUED AT 650 AM EDT WED JUL 29 2015
OVERALL CONDITIONS WILL REMAIN VFR AT ALL NRN LWR MICHIGAN TAF
SITES THRU WEDNESDAY NIGHT. A COLD FRONT WILL SWEEP THRU THE
REGION TODAY. LIMITED MOISTURE AND ONLY WEAK INSTABILITY ALONG AND
AHEAD OF THE FRONT WILL RESTRICT POPS TO ONLY CHANCE. EXPECT A
BAND OF SCATTERED SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS WILL
SLOWLY PUSH FROM WEST TO EAST THRU NRN LWR MICHIGAN THROUGHOUT
THE DAY. WILL CONTINUE TO HANDLE WITH VCSH IN THE TAFS FOR NOW.
SOUTH WINDS UNDER 10 KTS WILL SHIFT TO THE WEST IN THE WAKE OF THE
FRONT AND WILL INCREASE TO 10 TO 15 KTS...WITH A FEW HIGHER GUSTS
POSSIBLE.
&&
.MARINE...
ISSUED AT 331 AM EDT WED JUL 29 2015
CHANCES OF SHOWERS AND STORMS WILL INCREASE FROM WEST TO EAST TODAY
AS A COLD FRONT SWINGS THROUGH NORTHERN MICHIGAN. WINDS AND WAVES
WILL APPROACH SCA CRITERIA THIS AFTERNOON AND THIS EVENING AS WINDS
SHIFT TO THE WEST AND STRENGTHEN BEHIND THE COLD FRONT. AT THIS
POINT...EXPECT CONDITIONS WILL FALL JUST SHORT OF CRITERIA.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
NEAR TERM...MLR
SHORT TERM...JSL
LONG TERM...JSL
AVIATION...MLR
MARINE...MLR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
456 AM EDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EDT WED JUL 29 2015
FAIRLY IMPRESSIVE SURFACE AND UPPER LOW FOR LATE JULY IS LOCATED
JUST TO THE SOUTH OF LAKE WINNIPEG EARLY THIS MORNING...AND IT IS
KEEPING MUCH OF ITS ENERGY NEAR THE LOW IN MANITOBA. THIS HAS LED TO
A FAIRLY UNEVENTFUL PASSAGE OF THE COLD FRONT DUE TO THE LACK OF ANY
UPPER LEVEL SUPPORT/SHORTWAVES MOVING THROUGH THE AREA AND THE MID-
LEVEL DRY AIR AND CAPPING SEEN ON RAP ANALYSIS SOUNDINGS. THERE WAS
A THUNDERSTORM THAT MOVED NORTHEAST OUT OF NORTHWEST WISCONSIN
EARLIER IN THE NIGHT BUT DISSIPATED OVER WESTERN LAKE SUPERIOR. HAVE
SEEN SOME LIGHT SHOWER DEVELOPMENT OVER THE WESTERN U.P. OVER THE
LAST 1-2HRS AND THEY ARE MOVING NORTHEAST WHILE THE FRONT SHIFTS
THEM TO THE EAST. THERE HASN/T BEEN ANY LIGHTNING NOTED WITH THEM
THUS FAR...LARGELY DUE TO THEM STRUGGLING TO GET ABOVE THE FREEZING
LEVEL (HAVE PEAKED AROUND 15KFT). STILL THINK SOME THUNDER IS
POSSIBLE AS THEY ALIGN WITH A THIN AREA OF 500 J/KG OF MUCAPE AHEAD
OF THE FRONT AS SEEN ON THE SPC MESOSCALE ANALYSIS PAGE. THE COLD
FRONT WILL CONTINUE TO THE EAST THIS MORNING AND EXIT THE AREA BY
NOON. WILL CONTINUE TO SHOW SLIGHT CHANCE POPS RIGHT ALONG THE FRONT
AS IT MOVES EAST THIS MORNING...BUT DON/T EXPECT ANYTHING MORE THAN
AN ISOLATED SHOWER/THUNDERSTORM. HAVE SEEN A FAIRLY SIGNIFICANT DROP
IN DEWPOINTS BEHIND THE FRONT...AS KIWD WENT FROM A 72 DEGREE
DEWPOINT AT 535Z AND QUICKLY DROPPED TO 64 AT 615Z AND IS NOW AT 57
AT 735Z.
BEHIND THE FRONT...THE DRY SLOT SEEN ON WATER VAPOR IMAGERY WILL
MOVE THROUGH THE AREA AND LEAD TO AN AREA OF MOSTLY SUNNY START TO
THE DAY OVER THE WEST. DO EXPECT THE AREA OF CLOUDS IN NORTHEAST ND
AND NORTHWEST MN TO MOVE EAST INTO THE WESTERN CWA THIS AFTERNOON
AND BE AIDED BY DIURNAL HEATING TO PRODUCE DIURNAL CU ON THE LEADING
EDGE AND AHEAD OF THE CLOUDS INTO THE CENTRAL U.P. OVER THE
EAST...AFTER A CLOUDY START TO THE DAY...EXPECT A PERIOD OF MOSTLY
SUNNY SKIES AND THEN SOME DIURNAL CU IN AFTERNOON AND LINGERING INTO
THE EVENING. HIGHS TODAY WILL BE IN THE UPPER 70S OVER THE WEST AND
THE LOW-MID 80S OVER THE CENTRAL AND EAST.
THE MAIN HAZARD BEHIND THE FRONT WILL BE THE GUSTY WEST-SOUTHWEST
WINDS. THESE WINDS WILL BE AIDED BY THE TIGHT PRESSURE GRADIENT OVER
THE NORTHWEST HALF OF THE CWA AND LARGELY OVER NORTHWESTERN LAKE
SUPERIOR. HAVE ALREADY SEEN GUSTS TO 20-25KTS IMMEDIATELY BEHIND THE
FRONT EARLIER IN THE NIGHT AND CLOSER TO THE LOW WINDS HAVE BEEN
GUSTING TO 30-35KTS IN NORTHWEST MINNESOTA. THE AMPLE SUNSHINE THIS
MORNING WILL HELP TO MIX INTO THE 25-40KT WINDS AROUND 925MB TO THE
SURFACE...WITH THE STRONGEST WINDS OVER THE KEWEENAW PENINSULA. IN
THAT AREA...WOULD EXPECT GUSTS TO AROUND 35KTS BY MID AFTERNOON AND
THERE COULD BE A BRIEF PERIOD OF GUSTS TO 40KTS BY EARLY EVENING.
DON/T THINK THERE WILL BE A LONG ENOUGH PERIOD FOR A WIND ADVISORY
FOR THE KEWEENAW PENINSULA (NEED 39KTS)...SO WILL ISSUE AN SPS FOR
KEWEENAW AND NORTHERN HOUGHTON COUNTIES TO HIGHLIGHT THE WINDY
CONDITIONS FOR TODAY. THE REST OF THE U.P. WILL SEE WIND GUSTS OF 20-
30KTS...HIGHEST OVER THE WEST.
WITH THE MUCH DRIER AIR MOVING INTO THE AREA...THINK DEWPOINTS WILL
MIX OUT INTO THE UPPER 40S TO AROUND 50 OVER THE WEST/CENTRAL TODAY.
WHILE TEMPERATURES WILL BE COOLER THAN YESTERDAY...RH VALUES WILL
STILL FALL INTO THE 30S. THAT WILL LEAD TO AN ELEVATED RISK OF
WILDFIRES ACROSS MUCH OF THE U.P. TODAY. SINCE THE RH VALUES WILL BE
ABOVE RED FLAG CRITERIA...THIS SITUATION WOULD FALL UNDER AN RFD
PRODUCT DUE TO THE FREQUENT GUSTS OVER 25 MPH. SINCE COORDINATION
NEEDS TO BE DONE WITH FIRE WX USERS BEFORE ISSUANCE...WILL PASS
ALONG TO DAY SHIFT TO COORDINATE POTENTIAL ISSUANCE.
A SECONDARY TROUGH MOVES EAST ACROSS THE AREA TONIGHT. SOME CLOUDS
ASSOCIATED WITH IT...LARGELY OVER LAKE SUPERIOR...BUT NOT EXPECTING
ANY RAIN. THERE WILL STILL BE STRONG WINDS JUST ABOVE THE SURFACE
AGAIN TONIGHT...WHICH WILL HELP TO KEEP THE WINDS FROM DECOUPLING.
HAVE KEPT UP GUSTS OVER THE KEWEENAW PENINSULA (TO 20-30KTS)
...ESPECIALLY FOR THE EXPOSED LOCATIONS. OTHERWISE...THE REST OF THE
AREA WILL SEE WINDS TURNING WESTERLY WITH GUSTS TO 10-20KTS (HIGHEST
NORTH).
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 455 AM EDT WED JUL 29 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA AND A BROAD RIDGE IS
ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE FEATURES A NW
FLOW WILL DOMINATE THE GREAT LAKES REGION AS A SERIES OF MAINLY WEAK
SHORTWAVES PASSING THRU BRING CHCS FOR PERIODIC LIGHT SHOWERS.
TIMING OF THESE WEAK SHORTWAVES WILL LIKELY BE 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
TREND BELOW NORMAL TOWARD THE BEGINNING HALF OF NEXT WEEK AS A MID-
LVL TROUGH BEGINS TO AMPLIFY INTO THE UPPER GREAT LAKES REGION.
THU THROUGH FRI...MOST OF MODELS SHOW A WEAK SHORTWAVE MOVING
THROUGH THE AREA TOWARD THU EVENING WITH ANOTHER WEAK SHORTWAVE
MOVING THROUGH DURING THE DAY ON FRI. WITH SEVERAL OF THE MODELS
SHOWING A FEW HUNDRED J/KG OF MLCAPE EACH DAY MAINLY DURING THE
AFTERNOON/EVENING HRS WILL PROBABLY NEED TO MAINTAIN SLIGHT CHC POPS
EACH DAY FOR ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW
EXPECT ANY PCPN FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
FRI NIGHT AND SAT...ANOTHER SHORTWAVE MOVING THROUGH DURING THIS
TIME WILL WARRANT HAVING SLIGHT CHC POPS OVER MAINLY THE NW AND NE
CWA INCLUDING LAKE SUPERIOR.
TEMPERATURES THU THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS HAVE TRENDED FARTHER NORTH WITH MORE SIGNIFICANT SHORTWAVE
DUE TO MOVE IN SAT NIGHT INTO SUN SO HAVE BACKED OFF TO ONLY SLIGHT
CHANCE POPS FOR THAT TIME FRAME. BEST LIFT WITH SHORTWAVE STAYS
NORTH AND BETTER INSTABILITY AS INDICATED BY MODELS IS FARTHER
SOUTH.
TIMING OF SHORTWAVE AND ASSOC COLD FRONT FOR EARLY NEXT WEEK
DIFFERS BTWN THE 00Z GFS AND 00Z ECMWF. THE ECMWF IS QUICKER
BRINGING SYSTEM THROUGH SUN NIGHT INTO MON WHILE THE GFS DOESN/T
BRING SYSTEM THRU UNTIL LATE MON INTO MON NIGHT. THIS SYSTEM MAY
HAVE A BETTER CHC OF BRINGING MORE WIDESPREAD...ALTHOUGH LIGHT
PCPN...BUT GIVEN UNCERTAINTY IN TIMING AT THIS POINT DON/T HAVE
ANYTHING MORE THAN LOW CHC POPS. MODELS ADVERTISE TEMPS COOLING BELOW
NORMAL TEMPS BEHIND THE FRONTAL SYSTEM ESPECIALLY BY TUE. &&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 129 AM EDT WED JUL 29 2015
HIGH CLOUDS WILL BEGIN TO LOWER THIS EVENING RIGHT AHEAD AND ALONG A
COLD FRONT CROSSING W TO E OVER THE AREA. THE FRONT IS CURRENTLY JUST
TO THE WEST OF KIWD AND ALTHOUGH THERE MAY BE AN ISOLATED SHOWER OR
THUNDERSTORM...CONFIDENCE WAS TOO LOW TO INCLUDE IN THE TAF. LLWS IS
A CONCERN THROUGH THE EARLY MORNING HOURS TODAY AHEAD OF THE FRONT 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.
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EDT WED JUL 29 2015
A STRONG LOW PRESSURE SYSTEM FOR LATE JULY IS LOCATED NEAR LAKE
WINNIPEG EARLY THIS MORNING AND IT WILL LIFT NORTHEAST INTO FAR
NORTHERN ONTARIO TODAY. MEANWHILE...IT WILL SWEEP A COLD FRONT
CURRENTLY OVER CENTRAL LAKE SUPERIOR EAST ACROSS THE REST OF THE
LAKE THIS MORNING. BEHIND THE FRONT...SOUTHWEST WINDS WILL
INCREASE THROUGH THE MORNING OVER THE WESTERN HALF OF THE LAKE AND
PRODUCE GALES TO 35-40KTS. THERE COULD BE A FEW GUSTS IN THE 40-45KT
RANGE TOWARDS ISLE ROYALE THIS AFTERNOON. THESE WINDS WILL DECREASE
AND SHIFT TO THE WEST THIS EVENING AS THE FIRST IN A SERIES OF
TROUGHS MOVE ACROSS LAKE SUPERIOR THROUGH SUNDAY MORNING (ASSOCIATED
WITH THE SURFACE LOW SLOWLY DRIFTING OVER HUDSON BAY). THERE IS THE
POTENTIAL FOR GALES OUT OF THE WEST-NORTHWEST TONIGHT BEHIND THE
SECONDARY TROUGH AS THE PRESSURE GRADIENT REMAINS TIGHT OVER
NORTHERN LAKE SUPERIOR. BUT EXPECT THE MARINE LAYER TO BE THE
STRONGEST IN THAT AREA WITH THE WATER TEMPERATURES STILL IN THE
UPPER 30S AND LOWER 40S. WILL ADD A MENTION OF GALE FORCE GUSTS FOR
NOW. THE PRESSURE GRADIENT WILL GRADUALLY DECREASE THROUGH THE REST
OF THE WEAK AS ADDITIONAL WEAK SURFACE TROUGHS MOVE SOUTHEAST ACROSS
THE LAKE. EXPECT WINDS TO STAY BELOW 25KTS AFTER THURSDAY AND
THROUGH THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 8 AM EDT /7 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ THIS EVENING FOR LSZ162-240>242-263.
GALE WARNING FROM 11 AM THIS MORNING TO 11 PM EDT THIS EVENING
FOR LSZ264.
GALE WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING
FOR LSZ245>247.
GALE WARNING FROM 11 AM THIS MORNING TO 10 PM EDT THIS EVENING
FOR LSZ243-244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...07/SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
418 AM EDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 418 AM EDT WED JUL 29 2015
FAIRLY IMPRESSIVE SURFACE AND UPPER LOW FOR LATE JULY IS LOCATED
JUST TO THE SOUTH OF LAKE WINNIPEG EARLY THIS MORNING...AND IT IS
KEEPING MUCH OF ITS ENERGY NEAR THE LOW IN MANITOBA. THIS HAS LED TO
A FAIRLY UNEVENTFUL PASSAGE OF THE COLD FRONT DUE TO THE LACK OF ANY
UPPER LEVEL SUPPORT/SHORTWAVES MOVING THROUGH THE AREA AND THE MID-
LEVEL DRY AIR AND CAPPING SEEN ON RAP ANALYSIS SOUNDINGS. THERE WAS
A THUNDERSTORM THAT MOVED NORTHEAST OUT OF NORTHWEST WISCONSIN
EARLIER IN THE NIGHT BUT DISSIPATED OVER WESTERN LAKE SUPERIOR. HAVE
SEEN SOME LIGHT SHOWER DEVELOPMENT OVER THE WESTERN U.P. OVER THE
LAST 1-2HRS AND THEY ARE MOVING NORTHEAST WHILE THE FRONT SHIFTS
THEM TO THE EAST. THERE HASN/T BEEN ANY LIGHTNING NOTED WITH THEM
THUS FAR...LARGELY DUE TO THEM STRUGGLING TO GET ABOVE THE FREEZING
LEVEL (HAVE PEAKED AROUND 15KFT). STILL THINK SOME THUNDER IS
POSSIBLE AS THEY ALIGN WITH A THIN AREA OF 500 J/KG OF MUCAPE AHEAD
OF THE FRONT AS SEEN ON THE SPC MESOSCALE ANALYSIS PAGE. THE COLD
FRONT WILL CONTINUE TO THE EAST THIS MORNING AND EXIT THE AREA BY
NOON. WILL CONTINUE TO SHOW SLIGHT CHANCE POPS RIGHT ALONG THE FRONT
AS IT MOVES EAST THIS MORNING...BUT DON/T EXPECT ANYTHING MORE THAN
AN ISOLATED SHOWER/THUNDERSTORM. HAVE SEEN A FAIRLY SIGNIFICANT DROP
IN DEWPOINTS BEHIND THE FRONT...AS KIWD WENT FROM A 72 DEGREE
DEWPOINT AT 535Z AND QUICKLY DROPPED TO 64 AT 615Z AND IS NOW AT 57
AT 735Z.
BEHIND THE FRONT...THE DRY SLOT SEEN ON WATER VAPOR IMAGERY WILL
MOVE THROUGH THE AREA AND LEAD TO AN AREA OF MOSTLY SUNNY START TO
THE DAY OVER THE WEST. DO EXPECT THE AREA OF CLOUDS IN NORTHEAST ND
AND NORTHWEST MN TO MOVE EAST INTO THE WESTERN CWA THIS AFTERNOON
AND BE AIDED BY DIURNAL HEATING TO PRODUCE DIURNAL CU ON THE LEADING
EDGE AND AHEAD OF THE CLOUDS INTO THE CENTRAL U.P. OVER THE
EAST...AFTER A CLOUDY START TO THE DAY...EXPECT A PERIOD OF MOSTLY
SUNNY SKIES AND THEN SOME DIURNAL CU IN AFTERNOON AND LINGERING INTO
THE EVENING. HIGHS TODAY WILL BE IN THE UPPER 70S OVER THE WEST AND
THE LOW-MID 80S OVER THE CENTRAL AND EAST.
THE MAIN HAZARD BEHIND THE FRONT WILL BE THE GUSTY WEST-SOUTHWEST
WINDS. THESE WINDS WILL BE AIDED BY THE TIGHT PRESSURE GRADIENT OVER
THE NORTHWEST HALF OF THE CWA AND LARGELY OVER NORTHWESTERN LAKE
SUPERIOR. HAVE ALREADY SEEN GUSTS TO 20-25KTS IMMEDIATELY BEHIND THE
FRONT EARLIER IN THE NIGHT AND CLOSER TO THE LOW WINDS HAVE BEEN
GUSTING TO 30-35KTS IN NORTHWEST MINNESOTA. THE AMPLE SUNSHINE THIS
MORNING WILL HELP TO MIX INTO THE 25-40KT WINDS AROUND 925MB TO THE
SURFACE...WITH THE STRONGEST WINDS OVER THE KEWEENAW PENINSULA. IN
THAT AREA...WOULD EXPECT GUSTS TO AROUND 35KTS BY MID AFTERNOON AND
THERE COULD BE A BRIEF PERIOD OF GUSTS TO 40KTS BY EARLY EVENING.
DON/T THINK THERE WILL BE A LONG ENOUGH PERIOD FOR A WIND ADVISORY
FOR THE KEWEENAW PENINSULA (NEED 39KTS)...SO WILL ISSUE AN SPS FOR
KEWEENAW AND NORTHERN HOUGHTON COUNTIES TO HIGHLIGHT THE WINDY
CONDITIONS FOR TODAY. THE REST OF THE U.P. WILL SEE WIND GUSTS OF 20-
30KTS...HIGHEST OVER THE WEST.
WITH THE MUCH DRIER AIR MOVING INTO THE AREA...THINK DEWPOINTS WILL
MIX OUT INTO THE UPPER 40S TO AROUND 50 OVER THE WEST/CENTRAL TODAY.
WHILE TEMPERATURES WILL BE COOLER THAN YESTERDAY...RH VALUES WILL
STILL FALL INTO THE 30S. THAT WILL LEAD TO AN ELEVATED RISK OF
WILDFIRES ACROSS MUCH OF THE U.P. TODAY. SINCE THE RH VALUES WILL BE
ABOVE RED FLAG CRITERIA...THIS SITUATION WOULD FALL UNDER AN RFD
PRODUCT DUE TO THE FREQUENT GUSTS OVER 25 MPH. SINCE COORDINATION
NEEDS TO BE DONE WITH FIRE WX USERS BEFORE ISSUANCE...WILL PASS
ALONG TO DAY SHIFT TO COORDINATE POTENTIAL ISSUANCE.
A SECONDARY TROUGH MOVES EAST ACROSS THE AREA TONIGHT. SOME CLOUDS
ASSOCIATED WITH IT...LARGELY OVER LAKE SUPERIOR...BUT NOT EXPECTING
ANY RAIN. THERE WILL STILL BE STRONG WINDS JUST ABOVE THE SURFACE
AGAIN TONIGHT...WHICH WILL HELP TO KEEP THE WINDS FROM DECOUPLING.
HAVE KEPT UP GUSTS OVER THE KEWEENAW PENINSULA (TO 20-30KTS)
...ESPECIALLY FOR THE EXPOSED LOCATIONS. OTHERWISE...THE REST OF THE
AREA WILL SEE WINDS TURNING WESTERLY WITH GUSTS TO 10-20KTS (HIGHEST
NORTH).
.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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 129 AM EDT WED JUL 29 2015
HIGH CLOUDS WILL BEGIN TO LOWER THIS EVENING RIGHT AHEAD AND ALONG A
COLD FRONT CROSSING W TO E OVER THE AREA. THE FRONT IS CURRENTLY JUST
TO THE WEST OF KIWD AND ALTHOUGH THERE MAY BE AN ISOLATED SHOWER OR
THUNDERSTORM...CONFIDENCE WAS TOO LOW TO INCLUDE IN THE TAF. LLWS IS
A CONCERN THROUGH THE EARLY MORNING HOURS TODAY AHEAD OF THE FRONT 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.
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 AM EDT WED JUL 29 2015
A STRONG LOW PRESSURE SYSTEM FOR LATE JULY IS LOCATED NEAR LAKE
WINNIPEG EARLY THIS MORNING AND IT WILL LIFT NORTHEAST INTO FAR
NORTHERN ONTARIO TODAY. MEANWHILE...IT WILL SWEEP A COLD FRONT
CURRENTLY OVER CENTRAL LAKE SUPERIOR EAST ACROSS THE REST OF THE
LAKE THIS MORNING. BEHIND THE FRONT...SOUTHWEST WINDS WILL
INCREASE THROUGH THE MORNING OVER THE WESTERN HALF OF THE LAKE AND
PRODUCE GALES TO 35-40KTS. THERE COULD BE A FEW GUSTS IN THE 40-45KT
RANGE TOWARDS ISLE ROYALE THIS AFTERNOON. THESE WINDS WILL DECREASE
AND SHIFT TO THE WEST THIS EVENING AS THE FIRST IN A SERIES OF
TROUGHS MOVE ACROSS LAKE SUPERIOR THROUGH SUNDAY MORNING (ASSOCIATED
WITH THE SURFACE LOW SLOWLY DRIFTING OVER HUDSON BAY). THERE IS THE
POTENTIAL FOR GALES OUT OF THE WEST-NORTHWEST TONIGHT BEHIND THE
SECONDARY TROUGH AS THE PRESSURE GRADIENT REMAINS TIGHT OVER
NORTHERN LAKE SUPERIOR. BUT EXPECT THE MARINE LAYER TO BE THE
STRONGEST IN THAT AREA WITH THE WATER TEMPERATURES STILL IN THE
UPPER 30S AND LOWER 40S. WILL ADD A MENTION OF GALE FORCE GUSTS FOR
NOW. THE PRESSURE GRADIENT WILL GRADUALLY DECREASE THROUGH THE REST
OF THE WEAK AS ADDITIONAL WEAK SURFACE TROUGHS MOVE SOUTHEAST ACROSS
THE LAKE. EXPECT WINDS TO STAY BELOW 25KTS AFTER THURSDAY AND
THROUGH THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 8 AM EDT /7 AM CDT/ THIS MORNING TO 8 PM EDT
/7 PM CDT/ THIS EVENING FOR LSZ162-240>242-263.
GALE WARNING FROM 11 AM THIS MORNING TO 11 PM EDT THIS EVENING
FOR LSZ264.
GALE WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING
FOR LSZ245>247.
GALE WARNING FROM 11 AM THIS MORNING TO 10 PM EDT THIS EVENING
FOR LSZ243-244.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...TITUS
AVIATION...07/SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
331 AM EDT WED JUL 29 2015
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
PERSISTENT HIGH PRESSURE HAS SHIFTED EAST OF MICHIGAN EARLY THIS
MORNING AS A COLD FRONT APPROACHES FROM THE WEST. MID AND HIGH
CLOUDS HAVE BEGUN TO INCREASE ALONG THE NE PERIPHERY OF THE
CONVECTIVE CLOUD SHIELD GENERATED FROM THE MCS CURRENTLY IMPACTING
IOWA...NRN MISSOURI AND NRN ILLINOIS. THIS CONVECTION IS FUELED BY A
STRONG INSTABILITY AXIS (CAPES OF AROUND 3000 JOULES) AND 850 MB
THETA E RIDGING PUNCHING THRU THE MISSISSIPPI VALLEY ATTM. FURTHER
NORTH...OUR UPSTREAM RADARS SHOW A FEW SHOWERS AND EMBEDDED WEAK
STORMS TRYING TO DEVELOP JUST EAST OF THE ARROWHEAD OF MINNESOTA
OVER WRN LAKE SUPERIOR JUST AHEAD OF THE APPROACHING COLD FRONT.
CONVECTION IS STRUGGLING DUE TO WEAK INSTABILITY (500 JOULES OR
LESS) AND VERY LIMITED MOISTURE.
LATEST NAM12...RAP13 AND HRRR ALL SUGGEST THE FOCUS FOR MEANINGFUL
CONVECTIVE DEVELOPMENT WILL STAY SOUTH OF OUR CWA THRU TODAY WHERE
STRONGER INSTABILITY AND MUCH BETTER MOISTURE WILL RESIDE. NORTHERN
MICHIGAN IS ONCE AGAIN LOOKING AT THE PROSPECT THAT THE MAJORITY OF
OUR CWA MAY MISS OUT ON AN OPPORTUNITY FOR SOME MUCH NEEDED RAIN
TODAY. STILL...CHANCE POPS WILL REMAIN IN ORDER THRU THE DAY...WITH
THE EXPECTATION THAT A NARROW LINE OF SCATTERED SHOWERS WITH SOME
EMBEDDED THUNDERSTORMS WILL DEVELOP ALONG AND AHEAD OF THE COLD
FRONT. WILL MAKE SOME MINOR TIMING ADJUSTMENTS TO THIS BAND OF
PRECIP AS IT SLOWLY MOVES THRU OUR CWA TODAY...BUT WILL CERTAINLY
KEEP POPS IN THE CHANCE CATEGORY. NO REAL CHANCE FOR STRONG TO
SEVERE STORMS GIVEN LIMITED INSTABILITY AND MOISTURE AND
UNIMPRESSIVE WIND FIELDS AHEAD OF THE FRONT.
EXPECT ANOTHER VERY WARM DAY FOR NORTHERN MICHIGAN...BUT NOT AS WARM
AS IT HAS BEEN THE PAST FEW DAYS. HIGH TEMPS WILL WARM WELL INTO THE
80S...BUT SHOULD REFRAIN FROM REACHING INTO THE 90S. OVERNIGHT LOWS
WILL COOL BACK INTO THE 60S.
&&
.SHORT TERM...(THURSDAY THROUGH FRIDAY NIGHT)
ISSUED AT 331 AM EDT WED JUL 29 2015
(7/30)THURSDAY...WITH THE FRONTAL PASSAGE TODAY, THE TEMPERATURES
FALL BACK TO NORMAL FOR THURSDAY. THERE ARE TWO CONCERNS FOR THE DAY
AND INTO THE NIGHT. 1) CLOUD COVER, ESPECIALLY NEAR ANJ. THE 850 MB
RH IS AROUND 90%, AND WITH THE 850 MB TEMPERATURES NEAR +10C, NEAR E
UPPER, IT COULD BE CLOUDIER. WHICH LEADS TO 2) TEMPERATURES COULD
END UP COOLER IF THERE ARE MORE CLOUDS IN E UPPER AND EVEN PARTS OF
THE N LOWER IF THE CLOUDS MAKE IT DOWN FAR ENOUGH SOUTH, BUT THAT
SEEMS ONLY TO ABOUT M-32 AT THE MOST.
SOUTH OF M-32, HOWEVER, THERE IS A DIFFERENT CONCERN, FIRE WEATHER.
WILL EXPECT THAT THE HIGH TEMPERATURES WILL REMAIN OVER 75F (CIPS
ANALOG GUIDANCE SHOWS 70% AT THE TEMPERATURES>75F). WINDS WILL BE
AROUND 15MPH AT THE 20FT LEVEL (SUSTAINED), WITH THE RH AROUND 30-
35%. AND WITH THE EXTENDED DRY PERIOD, WILL BE GOING WITH THE
ELEVATED FIRE DANGER.
(7/31)FRIDAY...THE DISCUSSION FOR THURSDAY COULD VERY WELL FIT FOR
FRIDAY AS WELL, EXCEPT THAT THERE IS A WEAK SFC LOW TRYING TO MOVE
INTO THE REGION AS THE 500 MB LOW SINKS A LITTLE MORE SOUTH AND
BEGINS TO COOL THINGS DOWN A BIT. AGAIN THE COOLEST, PROBABLY
CLOUDIEST AREA WILL BE NORTH OF M-32, WITH THE SOO DROPPING INTO THE
LOWER 70S FOR HIGHS POSSIBLY. LOOKS LIKE WE ARE STILL AROUND 80S
SOUTH OF M-32, AND WINDS WILL BE AGAIN BE CLOSE TO 15 MPH AT 20FT,
SO THERE IS AN ELEVATED FIRE DANGER RISK, ALTHOUGH THE RH MAY NOT BE
AS BAD THURSDAY. HOWEVER, IT WILL STILL BE AN ISSUE.
&&
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 331 AM EDT WED JUL 29 2015
WITH THE 500 MB LOW JUST NORTH OF JAMES BAY, WE GO BACK TO THE
PATTERN THAT WE`VE HAD OVER N MICHIGAN THE LAST 2 YEARS WITH
COOLER THAN NORMAL TEMPERATURES AND POSSIBLY SHOWERY CONDITIONS,
BUT NOTHING APPRECIABLE, AT LEAST FOR THE TIME BEING. CIPS ANALOGS
FALL RIGHT IN LINE WITH THE MEX NUMBERS AS WELL AS THE ECMWF
IDEAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 100 AM EDT WED JUL 29 2015
OVERALL CONDITIONS WILL REMAIN VFR AT ALL NRN LWR MICHIGAN TAF
SITES THRU WEDNESDAY NIGHT. A COLD FRONT WILL SWEEP THRU THE
REGION TODAY. LIMITED MOISTURE AND ONLY WEAK INSTABILITY ALONG AND
AHEAD OF THE FRONT WILL RESTRICT POPS TO ONLY CHANCE. EXPECT A
BAND OF SCATTERED SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS WILL
SLOWLY PUSH FROM WEST TO EAST THRU NRN LWR MICHIGAN THROUGHOUT
THE DAY. AT THIS POINT...SHORT TERM MODELS ARE LEANING TOWARD
DIMINISHED COVERAGE...THUS WILL HANDLE WITH VCSH IN THE TAFS FOR
NOW. SOUTH WINDS UNDER 10 KTS WILL SHIFT TO THE WEST IN THE WAKE
OF THE FRONT AND WILL INCREASE TO 10 TO 15 KTS...WITH A FEW HIGHER
GUSTS POSSIBLE.
&&
.MARINE...
ISSUED AT 331 AM EDT WED JUL 29 2015
CHANCES OF SHOWERS AND STORMS WILL INCREASE FROM WEST TO EAST TODAY
AS A COLD FRONT SWINGS THROUGH NORTHERN MICHIGAN. WINDS AND WAVES
WILL APPROACH SCA CRITERIA THIS AFTERNOON AND THIS EVENING AS WINDS
SHIFT TO THE WEST AND STRENGTHEN BEHIND THE COLD FRONT. AT THIS
POINT...EXPECT CONDITIONS WILL FALL JUST SHORT OF CRITERIA.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
NEAR TERM...MLR
SHORT TERM...JSL
LONG TERM...JSL
AVIATION...MLR
MARINE...MLR
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
330 AM EDT WED JUL 29 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 330 AM EDT WED JUL 29 2015
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A COLD
FRONT CROSSES THE REGION. GUSTY WESTERLY WINDS BEHIND THE FRONT WILL
USHER IN MORE COMFORTABLE LESS HUMID AIR FOR THE REMAINDER OF THE
WEEK ALTHOUGH HIGHS WILL REMAIN IN THE LOWER TO MID 80S.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
ISOLATED SHOWERS HAVE DEVELOPED OVERNIGHT ON THE LEADING EDGE OF THE
HIGHER PRECIPITABLE WATER AROUND TWO INCHES MOVING IN FROM THE
SOUTHWEST AHEAD OF THE APPROACHING COLD FRONT. SUSPECT COVERAGE OF
SHOWERS WILL REMAIN RATHER LIMITED THIS MORNING ACROSS SW LWR MI AS
MORE EXPANSIVE AREA OF CONVECTION IMPACTS IOWA AND ILLINOIS.
OUR BEST PROSPECTS FOR BETTER COVERAGE OF STORMS WILL BE THIS
AFTERNOON EAST OF HIGHWAY 131 WHERE SB CAPES NEAR 1500 J/KG ARE
PROGGED JUST AHEAD OF THE FRONT. RUC FCST SNDGS EXHIBIT STEEP LOW
LEVEL LAPSE RATES WITH SFC TO 3 KM AROUND 8.5C NEAR JXN. BASED ON
THE HIGH PWAT VALUES OF UP TO 2.25 INCHES WE WILL HAVE TO WATCH OF
THE POSSIBILITY OF SOME TORRENTIAL RAINFALL AND POSSIBLY A LOCALIZED
WET MICROBURST DAMAGING WIND EVENT.
CONVECTION ENDS FROM WEST TO EAST 18Z-22Z WITH THE PASSAGE OF THE
FRONT THEN DECREASING CLOUDS AND FALLING SFC DEW PTS EXPECTED.
BREEZY CONDITIONS EXPECTED THURSDAY ONCE DEEPER MIXING COMMENCES.
SOME GUSTS TO 30 MPH WILL BE POSSIBLE IN THE AFTERNOON.
HAVE KEPT FRIDAY DRY FOR NOW ALTHOUGH SOME SMALL POPS MAY NEED TO BE
ADDED IN LATER FCSTS AS NEXT WEAK FRONT/TROUGH DROPS SOUTH.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM EDT WED JUL 29 2015
THERE HAS NOT BEEN MUCH CHANGE OVER THE THE PAST FEW DAYS WITH
REGARD TO THE EXPECTED PATTERN. WE CONTINUE TO EXPECT LITTLE TO NO
RAIN THROUGH SAT...BEFORE AN UNSETTLED WEATHER PATTERN TAKES SHAPE
LATER THIS WEEKEND AND INTO NEXT WEEK.
WE HAVE CONTINUED WITH A DRY FCST FOR THE FRI NIGHT AND SAT TIME
FRAME FOR NOW. WE WILL SEE WHAT IS LEFT OF THE WEAKENING COLD FRONT
TRYING TO MOVE THROUGH ON FRI SLIP SE OF THE AREA FRI EVENING. WE
CAN NOT RULE OUT A SHOWER DEVELOPING NEAR THIS FRONT...HOWEVER THE
CHC IS LOW ENOUGH TO LEAVE OUT OF THE FCST FOR THE TIME BEING. A
LACK OF MOISTURE WITH THE FRI FRONT WILL ONLY DIMINISH BY SAT AS THE
FRONT MOVES OUT. THERE IS NOT REALLY SIGNIFICANTLY COOLER AIR BEHIND
THIS...SO WE CONTINUE TO EXPECT HIGHS AROUND 80.
THE CHCS OF RAIN DOES GO UP ON SUN...AND WILL CONTINUE THROUGH THE
END OF THE PERIOD ON TUE. THE AREA WILL BE UNDER THE INFLUENCE OF
BROAD LONG WAVE TROUGHING CENTERED WELL NORTH IN CANADA. WE WILL SEE
THE JET CORE DROP A LITTLE FURTHER SOUTH WITH A TRAIN OF SHORT WAVES
HELPING THIS CAUSE. BEING CLOSER TO THE JET...WE WILL HAVE MORE OF
AN OPPORTUNITY FOR THE SHORT WAVES TO DIRECTLY IMPACT THE AREA. WE
WILL ALSO SEE THE LOW LEVEL FLOW BECOME A LITTLE MORE FAVORABLE TO
BRING SUFFICIENT MOISTURE TO THE AREA FOR RAIN. EXACT TIMING OF THE
SHORT WAVES WILL BE PROBLEMATIC AS IS USUAL IN A PATTERN LIKE THIS.
TEMPERATURES DO NOT LOOK TO BE TOO BAD IN THIS PATTERN. THE
UNSEASONABLY COOL AIR WILL REMAIN JUST NORTH OF THE STATE...NORTH OF
THE JET CORE. WE WILL SEE AVERAGE TO JUST SLIGHTLY BELOW AVERAGE
TEMPS DURING THIS PERIOD FOR OUR AREA. THIS EQUATES TO HIGHS
GENERALLY AROUND 80 AND LOWS AROUND 60.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 149 AM EDT WED JUL 29 2015
OUR MAIN FOCUS WITH THE 06Z FCST IS THE POTENTIAL OF SHOWERS
AND/OR STORMS WITH A FRONT THAT WILL MOVE THROUGH TODAY.
WE HAVE ACCOUNTED FOR A COUPLE POP UP SHOWERS NEAR KMKG FOR THE
FIRST HOUR OF THE VALID FCST PERIOD. THESE WILL PRODUCE SOME LOCAL
MVFR IN RAIN ESPECIALLY SOUTH OF KMKG...BUT WILL MOVE OUT QUICKLY
AND WILL LIKELY NOT HIT THE OTHER SITES.
WE EXPECTED A SCT LINE OF SHOWERS TO FORM WEST OF THE AREA TOWARD
12Z AND THEN SHIFT EAST THROUGH THE MORNING. NOT SURE ALL OF THE
SITES WILL BE DIRECTLY HIT...SO WE HAVE USED A VCSH TO COVER THIS
POTENTIAL. IF A SITE GETS HIT BY A SHOWER...SOME MVFR OR EVEN
BRIEF IFR WILL BE POSSIBLE. SOME OF THE SHOWERS COULD BE STORMS
TOWARD KLAN AND KJXN THIS AFTERNOON BEFORE EVERYTHING MOVES OUT OF
THE AREA BY AROUND 22Z.
SOME GUSTY WINDS WILL BE POSSIBLE RIGHT BEHIND THE FRONT/SHOWERS.
THE WINDS WILL DIMINISH TOWARD SUNSET WITH CLEARING SKIES.
&&
.MARINE...
ISSUED AT 330 AM EDT WED JUL 29 2015
CONDITIONS MAY APPROACH SMALL CRAFT ADVISORY CRITERIA LATE TONIGHT
AND EARLY THURSDAY DUE TO STRONG WESTERLY FLOW BEHIND THE COLD
FRONT. THIS WILL NEED TO BE MONITORED. THIS SITUATION COULD ALSO
SUPPORT BEACH HAZARD STATEMENTS ESPECIALLY CONSIDERING THE CURRENT
WARM WATER TEMPERATURES AND OVERALL ATTRACTIVE BEACH CONDITIONS
SUPPORTIVE OF A HIGH BEACH POPULATION.
&&
.HYDROLOGY...
ISSUED AT 1250 PM EDT TUE JUL 28 2015
RIVER LEVELS ARE FALLING AND WELL BELOW BANKFULL. WITH UNDER A
HALF INCH OF PRECIPITATION EXPECTED INTO NEXT WEEK... THESE
CONDITIONS SHOULD CONTINUE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
515 PM CDT WED JUL 29 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 331 PM CDT WED JUL 29 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.
CARNEY
.LONG TERM: (THURSDAY THROUGH NEXT WEDNESDAY)
ISSUED AT 352 PM CDT WED JUL 29 2015
AIR TEMPERATURES BEHIND THE FRONT ON THURSDAY WILL NOT BE THAT MUCH
COOLER THAN TODAY. HOWEVER, SHOULD HAVE DEWPOINT TEMPERATURES AS
MUCH AS 10-15 DEGREES COOLER SO WHILE IT WILL STILL BE HOT, IT
SHOULD FEEL SIGNIFICANTLY LESS BAD. NORTHWEST FLOW ALOFT WILL BRING
ANOTHER WEAK COLD FRONT SOUTHEAST THROUGH THE BI-STATE REGION FRIDAY
NIGHT. THERE APPEARS TO BE VERY LITTLE IF ANY RETURN FLOW AHEAD OF
THE FRONT, SO UNLESS EVAPOTRANSPIRATION CAN RAISE THE DEWPOINTS
SIGNIFICANTLY AHEAD OF THE FRONT, IT MIGHT GO THROUGH DRY. HOWEVER,
NAM AND GFS ARE PRINTING OUT SOME PRECIP ALONG THE FRONT FRIDAY
AFTERNOON AND FRIDAY NIGHT OVER NORTHERN MISSOURI AND WEST CENTRAL
ILLINOIS, SO HAVE INTRODUCED SOME SLIGHT CHANCE POPS. AFTER THE
FRONT GOES THROUGH IT LOOKS LIKE A DRY AND CONTINUED WARM FORECAST
AT LEAST UNTIL MONDAY OR MONDAY NIGHT WHEN ANOTHER COLD FRONT DIPS
SOUTH ACROSS THE MIDWEST. THE STRONG HIGH NORTH OF THE FRONT MOVES
SOUTHEAST ACROSS THE GREAT LAKES INTO THE OHIO VALLEY TUESDAY NIGHT
INTO WEDNESDAY, BUT WE STAY ON THE PERIPHERY, AND CURRENT MEDIUM
RANGE SOLUTIONS KEEP THE FRONT WAVERING BETWEEN CENTRAL MISSOURI AND
THE MISSISSIPPI RIVER THROUGH EARLY THURSDAY MORNING. THIS WILL
KEEP A CHANCE OF PRECIP IN THE FORECAST INTO THE LATTER PART OF THE
WEEK.
CARNEY
&&
.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 71 91 72 91 / 5 0 0 10
QUINCY 65 89 66 89 / 0 0 0 20
COLUMBIA 67 89 67 90 / 0 0 0 10
JEFFERSON CITY 67 91 66 91 / 0 0 0 10
SALEM 67 89 67 89 / 10 0 0 10
FARMINGTON 68 89 65 89 / 10 0 0 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
352 PM CDT WED JUL 29 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 331 PM CDT WED JUL 29 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.
CARNEY
.LONG TERM: (THURSDAY THROUGH NEXT WEDNESDAY)
ISSUED AT 352 PM CDT WED JUL 29 2015
AIR TEMPERATURES BEHIND THE FRONT ON THURSDAY WILL NOT BE THAT MUCH
COOLER THAN TODAY. HOWEVER, SHOULD HAVE DEWPOINT TEMPERATURES AS
MUCH AS 10-15 DEGREES COOLER SO WHILE IT WILL STILL BE HOT, IT
SHOULD FEEL SIGNIFICANTLY LESS BAD. NORTHWEST FLOW ALOFT WILL BRING
ANOTHER WEAK COLD FRONT SOUTHEAST THROUGH THE BI-STATE REGION FRIDAY
NIGHT. THERE APPEARS TO BE VERY LITTLE IF ANY RETURN FLOW AHEAD OF
THE FRONT, SO UNLESS EVAPOTRANSPIRATION CAN RAISE THE DEWPOINTS
SIGNIFICANTLY AHEAD OF THE FRONT, IT MIGHT GO THROUGH DRY. HOWEVER,
NAM AND GFS ARE PRINTING OUT SOME PRECIP ALONG THE FRONT FRIDAY
AFTERNOON AND FRIDAY NIGHT OVER NORTHERN MISSOURI AND WEST CENTRAL
ILLINOIS, SO HAVE INTRODUCED SOME SLIGHT CHANCE POPS. AFTER THE
FRONT GOES THROUGH IT LOOKS LIKE A DRY AND CONTINUED WARM FORECAST
AT LEAST UNTIL MONDAY OR MONDAY NIGHT WHEN ANOTHER COLD FRONT DIPS
SOUTH ACROSS THE MIDWEST. THE STRONG HIGH NORTH OF THE FRONT MOVES
SOUTHEAST ACROSS THE GREAT LAKES INTO THE OHIO VALLEY TUESDAY NIGHT
INTO WEDNESDAY, BUT WE STAY ON THE PERIPHERY, AND CURRENT MEDIUM
RANGE SOLUTIONS KEEP THE FRONT WAVERING BETWEEN CENTRAL MISSOURI AND
THE MISSISSIPPI RIVER THROUGH EARLY THURSDAY MORNING. THIS WILL
KEEP A CHANCE OF PRECIP IN THE FORECAST INTO THE LATTER PART OF THE
WEEK.
CARNEY
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1248 PM CDT WED JUL 29 2015
VFR FCST AT THE TERMINALS THRU THE PRD. SFC COLD FRONT IS SOUTH
OF ALL THE TERMINAL AS OF EARLY THIS AFTN...ACROSS STHRN IL INTO
SE MO. ISLD CONVECTION IS IN THE PROCESS OF DVLPNG ALONG THE BNDRY
ACROSS STHRN IL AS OF 18Z...AND EXPECT THIS TO CONTINUE TO DVLP TO
THE SW ACROSS SE MO. THIS ACTIVITY IS DVLPNG WITHIN THE BAND OF
MVFR CIGS THAT MOVED THRU THE STL METRO TERMINALS. THE SHRAS/TSTMS
WILL CONTINUE TO PUSH SE ALONG WITH THE BNDRY. BEHIND THE
FRONT...WINDS HAVE TURNED TO THE NORTH FILTERING IN DRIER AIR.
WINDS WILL GRADUALLY BECOME W/WNW BY THU MRNG.
SPECIFICS FOR KSTL:
VFR FCST THRU THE PRD WITH N WIND THIS AFTN BCMNG W/WNW BY THRU
MRNG. THE THREAT OF PRECIP IS FCST TO REMAIN SOUTH OF THE TERMINAL
THIS AFTN.
2%
&&
.PRELIMINARY POINT TEMPS/POPS:
SAINT LOUIS 71 91 72 91 / 5 0 0 10
QUINCY 65 89 66 89 / 0 0 0 20
COLUMBIA 67 89 67 90 / 0 0 0 10
JEFFERSON CITY 67 91 66 91 / 0 0 0 10
SALEM 67 89 67 89 / 10 0 0 10
FARMINGTON 68 89 65 89 / 10 0 0 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
332 PM CDT WED JUL 29 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 331 PM CDT WED JUL 29 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.
CARNEY
.LONG TERM: (TONIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CDT WED JUL 29 2015
A TWO-DAY RESPITE FROM THE OPPRESSIVE HEAT/HUMIDITY IS EXPECTED
ON THU/FRI. TEMPERATURES SHOULD BE SEASONABLY WARM (UPPER 80S TO
LOWER 90S), BUT THE DEW POINTS WILL BE MUCH LOWER THAN THEY HAVE
BEEN RECENTLY.
THE UPPER AIR PATTERN WILL HAVE TRANSITIONED TO NORTHWEST FLOW
ALOFT BY FRIDAY DUE TO THE BUILDING RIDGE ACROSS THE WESTERN CONUS
AND A TROUGH OVER THE EASTERN CONUS. MODELS SHOW THAT THIS NW
FLOW PATTERN REMAINS UNCHANGED THROUGH EARLY NEXT WEEK. ALTHOUGH
THE MODELS CONTINUE TO SHOW HINTS OF A SHORTWAVE OR TWO WHICH
COULD SUPPORT CONVECTION (PERHAPS AS EARLY AS SATURDAY NIGHT),
CONFIDENCE IN THE TIMING AND PLACEMENT OF THESE FEATURES IS LOW.
TEMPERATURES LOOK SEASONABLY WARM IN THE UPPER 80S TO LOWER 90S
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
KANOFSKY
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1248 PM CDT WED JUL 29 2015
VFR FCST AT THE TERMINALS THRU THE PRD. SFC COLD FRONT IS SOUTH
OF ALL THE TERMINAL AS OF EARLY THIS AFTN...ACROSS STHRN IL INTO
SE MO. ISLD CONVECTION IS IN THE PROCESS OF DVLPNG ALONG THE BNDRY
ACROSS STHRN IL AS OF 18Z...AND EXPECT THIS TO CONTINUE TO DVLP TO
THE SW ACROSS SE MO. THIS ACTIVITY IS DVLPNG WITHIN THE BAND OF
MVFR CIGS THAT MOVED THRU THE STL METRO TERMINALS. THE SHRAS/TSTMS
WILL CONTINUE TO PUSH SE ALONG WITH THE BNDRY. BEHIND THE
FRONT...WINDS HAVE TURNED TO THE NORTH FILTERING IN DRIER AIR.
WINDS WILL GRADUALLY BECOME W/WNW BY THU MRNG.
SPECIFICS FOR KSTL:
VFR FCST THRU THE PRD WITH N WIND THIS AFTN BCMNG W/WNW BY THRU
MRNG. THE THREAT OF PRECIP IS FCST TO REMAIN SOUTH OF THE TERMINAL
THIS AFTN.
2%
&&
.PRELIMINARY POINT TEMPS/POPS:
SAINT LOUIS 71 91 72 91 / 5 0 0 10
QUINCY 65 89 66 89 / 0 0 0 20
COLUMBIA 67 89 67 90 / 0 0 0 10
JEFFERSON CITY 67 91 66 91 / 0 0 0 10
SALEM 67 89 67 89 / 10 0 0 10
FARMINGTON 68 89 65 89 / 10 0 0 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1211 PM CDT WED JUL 29 2015
.UPDATE:
ISSUED AT 1159 AM CDT WED JUL 29 2015
EXCESSIVE HEAT WARNING WILL BE CANCELLED SHORTLY FOR A GOOD CHUNK
OF THE AREA. CLOUDS AND AND LOWER DEWPOINTS ARE FILTERING IN
BEHIND THE FRONT AND IT LOOKS LIKE 105 HEAT INDEX VALUES WON`T BE
ACHIEVED TODAY.
CARNEY
&&
.SHORT TERM: (THROUGH LATE THIS AFTERNOON)
ISSUED AT 311 AM CDT WED JUL 29 2015
08Z SURFACE ANALYSIS REVEALS THAT THE EAGERLY-AWAITED COLD FRONT
(AND ITS NOTICEABLY LESS HUMID POST-FRONTAL AIR MASS) WAS
TANTALIZINGLY CLOSE TO THE LSX CWA EARLY THIS MORNING. AT 08Z,
THE FRONT STRETCHED FROM CENTRAL KS THROUGH EXTREME SOUTHEASTERN
NEB AND THROUGH CENTRAL IA INTO WESTERN WI. A NOCTURNAL MCS AHEAD
OF THE FRONT WAS MAKING STEADY SOUTHWARD PROGRESS BUT VERY SLOW
EASTWARD PROGRESS. ADDITIONAL THUNDERSTORMS ARE POSSIBLE WITH THE
FRONT TODAY AS IT MOVES INTO A MOIST AND UNSTABLE AIR MASS DURING
THE AFTERNOON HOURS, AND THE OUTFLOW BOUNDARY MAY ALSO SERVE AS A
TRIGGER FOR AFTN SH/TS.
UNTIL THE COLD FRONT ARRIVES, THERE WILL BE VERY LITTLE CHANGE IN
THE SOUPY AIR MASS STILL IN PLACE ACROSS THE REGION. THE TIMING
OF THE COLD FRONT IS SUCH THAT ROUGHLY THE SOUTHERN TO
SOUTHEASTERN HALF OF THE CWA SHOULD SEE ANOTHER DAY OF HOT/HUMID
CONDITIONS, ALBEIT NOT AS OPPRESSIVE AS YESTERDAY. HEAT INDEX
VALUES SHOULD BE CLOSER TO 105-109 IN THE WORST AREAS TODAY
COMPARED TO THE HEAT INDICES OF 110-117 WHICH WERE OBSERVED
YESTERDAY. DESPITE THE SLIGHTLY LOWER HEAT INDEX VALUES WHICH ARE
EXPECTED TODAY, THE EXCESSIVE HEAT WARNING STILL LOOKS APPROPRIATE
BECAUSE IT IS THE CUMULATIVE EXPOSURE TO EXCESSIVE HEAT WHICH
NEGATIVELY AFFECTS THE HUMAN BODY, AND TODAY WILL BE THE THIRD OR
FOURTH DAY OF SUCH CONDITIONS FOR SOME AREAS.
KANOFSKY
.LONG TERM: (TONIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CDT WED JUL 29 2015
A TWO-DAY RESPITE FROM THE OPPRESSIVE HEAT/HUMIDITY IS EXPECTED
ON THU/FRI. TEMPERATURES SHOULD BE SEASONABLY WARM (UPPER 80S TO
LOWER 90S), BUT THE DEW POINTS WILL BE MUCH LOWER THAN THEY HAVE
BEEN RECENTLY.
THE UPPER AIR PATTERN WILL HAVE TRANSITIONED TO NORTHWEST FLOW
ALOFT BY FRIDAY DUE TO THE BUILDING RIDGE ACROSS THE WESTERN CONUS
AND A TROUGH OVER THE EASTERN CONUS. MODELS SHOW THAT THIS NW
FLOW PATTERN REMAINS UNCHANGED THROUGH EARLY NEXT WEEK. ALTHOUGH
THE MODELS CONTINUE TO SHOW HINTS OF A SHORTWAVE OR TWO WHICH
COULD SUPPORT CONVECTION (PERHAPS AS EARLY AS SATURDAY NIGHT),
CONFIDENCE IN THE TIMING AND PLACEMENT OF THESE FEATURES IS LOW.
TEMPERATURES LOOK SEASONABLY WARM IN THE UPPER 80S TO LOWER 90S
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
KANOFSKY
&&
.AVIATION: (FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 638 AM CDT WED JUL 29 2015
LARGE CONVECTIVE COMPLEX THAT BLANKETED MOST OF S IA AND N MO LATE
YESTERDAY EVENING BECAME OUTFLOW DOMINATED SHORTLY AFTER
05Z...WITH MAIN ELEMENTS DEVELOPING/PROPAGATING SSW WHILE E EDGE
REMAINED Q-STATIONARY BETWEEN KIRK-KUIN.
IN THE SHORT TERM...E EDGE OF THIS DYING PRECIP AREA MAY CLIP
KUIN OVER THE NEXT HOUR OR SO, WHILE DRY WEATHER WILL PREVAIL
ELSEWHERE. VFR CONDITIONS ARE ANTICIPATED...WITH CLOUDS AOA 4KFT.
CURRENT SURFACE ANALYSIS AND LATEST RAP GUIDANCE SUGGESTS TWO
BOUNDARIES THAT COULD PROVIDE FOCUS FOR AFTERNOON CONVECTION...THE
FIRST IS THE OUTFLOW FROM THE EARLY MORNING CONVECTION WHICH
APPEARS TO BE PUSHING THROUGH STL AREA ATTM. THE SECOND BOUNDARY
WILL BE THE ACTUAL SYNOPTIC FRONT. ITS CURRENT LOCATION IS BEING
MASKED BY MESOSCALE IMPACTS OF OVERNIGHT CONVECTION BUT IT APPEARS
TO BE OVER S CENTRAL/SE IA...AND RAP SUGGESTS IT WILL BE WITH
FRONT NEAR THE STL METRO BY MIDDAY. CONVERGENCE WILL BE FAIRLY
WEAK BUT THERE SHOULD CERTAINLY BE ENOUGH INSTABILITY TO CARRY
CURRENT VCTS AT STL METRO TAF SITES IN THE EARLY AFTERNOON.
HOWEVER...HAVE DROPPED MENTION OF VCTS AT KCOU SINCE CONVERGENCE
ALONG SYNOPTIC FRONT SHOULD BE SOUTH OF THAT AREA. PREVAILING
CONDITIONS ACROSS THE AREA FOR THE AFTERNOON HOURS SHOULD BE SCT-
BKN CU 4-5KFT (WITH GREATEST CLOUD COVER NEAR/SOUTH OF COLD
FRONT)...WITH THIS CU FIELD QUICKLY DISSIPATING DURING THE EARLY
EVENING WITH LOSS OF HEATING AND AS THE DRIER POST-FRONTAL AIR
ADVECTS INTO THE AREA.
SPECIFICS FOR KSTL: SCATTERED CLOUDS AOA 4KFT ARE EXPECTED THIS
MORNING...WITH CU FIELD AOA 4KFT BECOMING SCT-BKN BY LATE MORNING
AND INTO THE AFTERNOON. HAVE CONTINUED VCTS IN THE 18-21 TIME
FRAME AS SYNOPTIC FRONT WILL BE PASSING AT THAT TIME. CU FIELD
SHOULD QUICKLY DISSIPATE HEADING INTO THE EARLY EVENING...WITH
A FEW CLOUDS AOA 10KFT OVERNIGHT AND INTO EARLY THURSDAY.
TRUETT
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...EXCESSIVE HEAT WARNING UNTIL 9 PM CDT THIS EVENING FOR IRON MO-
MADISON MO-REYNOLDS MO-ST. FRANCOIS MO-STE. GENEVIEVE MO.
IL...EXCESSIVE HEAT WARNING UNTIL 9 PM CDT THIS EVENING FOR MARION IL-
RANDOLPH IL-WASHINGTON IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
702 AM CDT WED JUL 29 2015
.SHORT TERM: (THROUGH LATE THIS AFTERNOON)
ISSUED AT 311 AM CDT WED JUL 29 2015
08Z SURFACE ANALYSIS REVEALS THAT THE EAGERLY-AWAITED COLD FRONT
(AND ITS NOTICEABLY LESS HUMID POST-FRONTAL AIR MASS) WAS
TANTALIZINGLY CLOSE TO THE LSX CWA EARLY THIS MORNING. AT 08Z,
THE FRONT STRETCHED FROM CENTRAL KS THROUGH EXTREME SOUTHEASTERN
NEB AND THROUGH CENTRAL IA INTO WESTERN WI. A NOCTURNAL MCS AHEAD
OF THE FRONT WAS MAKING STEADY SOUTHWARD PROGRESS BUT VERY SLOW
EASTWARD PROGRESS. ADDITIONAL THUNDERSTORMS ARE POSSIBLE WITH THE
FRONT TODAY AS IT MOVES INTO A MOIST AND UNSTABLE AIR MASS DURING
THE AFTERNOON HOURS, AND THE OUTFLOW BOUNDARY MAY ALSO SERVE AS A
TRIGGER FOR AFTN SH/TS.
UNTIL THE COLD FRONT ARRIVES, THERE WILL BE VERY LITTLE CHANGE IN
THE SOUPY AIR MASS STILL IN PLACE ACROSS THE REGION. THE TIMING
OF THE COLD FRONT IS SUCH THAT ROUGHLY THE SOUTHERN TO
SOUTHEASTERN HALF OF THE CWA SHOULD SEE ANOTHER DAY OF HOT/HUMID
CONDITIONS, ALBEIT NOT AS OPPRESSIVE AS YESTERDAY. HEAT INDEX
VALUES SHOULD BE CLOSER TO 105-109 IN THE WORST AREAS TODAY
COMPARED TO THE HEAT INDICES OF 110-117 WHICH WERE OBSERVED
YESTERDAY. DESPITE THE SLIGHTLY LOWER HEAT INDEX VALUES WHICH ARE
EXPECTED TODAY, THE EXCESSIVE HEAT WARNING STILL LOOKS APPROPRIATE
BECAUSE IT IS THE CUMULATIVE EXPOSURE TO EXCESSIVE HEAT WHICH
NEGATIVELY AFFECTS THE HUMAN BODY, AND TODAY WILL BE THE THIRD OR
FOURTH DAY OF SUCH CONDITIONS FOR SOME AREAS.
KANOFSKY
.LONG TERM: (TONIGHT THROUGH TUESDAY)
ISSUED AT 311 AM CDT WED JUL 29 2015
A TWO-DAY RESPITE FROM THE OPPRESSIVE HEAT/HUMIDITY IS EXPECTED
ON THU/FRI. TEMPERATURES SHOULD BE SEASONABLY WARM (UPPER 80S TO
LOWER 90S), BUT THE DEW POINTS WILL BE MUCH LOWER THAN THEY HAVE
BEEN RECENTLY.
THE UPPER AIR PATTERN WILL HAVE TRANSITIONED TO NORTHWEST FLOW
ALOFT BY FRIDAY DUE TO THE BUILDING RIDGE ACROSS THE WESTERN CONUS
AND A TROUGH OVER THE EASTERN CONUS. MODELS SHOW THAT THIS NW
FLOW PATTERN REMAINS UNCHANGED THROUGH EARLY NEXT WEEK. ALTHOUGH
THE MODELS CONTINUE TO SHOW HINTS OF A SHORTWAVE OR TWO WHICH
COULD SUPPORT CONVECTION (PERHAPS AS EARLY AS SATURDAY NIGHT),
CONFIDENCE IN THE TIMING AND PLACEMENT OF THESE FEATURES IS LOW.
TEMPERATURES LOOK SEASONABLY WARM IN THE UPPER 80S TO LOWER 90S
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK.
KANOFSKY
&&
.AVIATION: (FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 638 AM CDT WED JUL 29 2015
LARGE CONVECTIVE COMPLEX THAT BLANKETED MOST OF S IA AND N MO LATE
YESTERDAY EVENING BECAME OUTFLOW DOMINATED SHORTLY AFTER
05Z...WITH MAIN ELEMENTS DEVELOPING/PROPAGATING SSW WHILE E EDGE
REMAINED Q-STATIONARY BETWEEN KIRK-KUIN.
IN THE SHORT TERM...E EDGE OF THIS DYING PRECIP AREA MAY CLIP
KUIN OVER THE NEXT HOUR OR SO, WHILE DRY WEATHER WILL PREVAIL
ELSEWHERE. VFR CONDITIONS ARE ANTICIPATED...WITH CLOUDS AOA 4KFT.
CURRENT SURFACE ANALYSIS AND LATEST RAP GUIDANCE SUGGESTS TWO
BOUNDARIES THAT COULD PROVIDE FOCUS FOR AFTERNOON CONVECTION...THE
FIRST IS THE OUTFLOW FROM THE EARLY MORNING CONVECTION WHICH
APPEARS TO BE PUSHING THROUGH STL AREA ATTM. THE SECOND BOUNDARY
WILL BE THE ACTUAL SYNOPTIC FRONT. ITS CURRENT LOCATION IS BEING
MASKED BY MESOSCALE IMPACTS OF OVERNIGHT CONVECTION BUT IT APPEARS
TO BE OVER S CENTRAL/SE IA...AND RAP SUGGESTS IT WILL BE WITH
FRONT NEAR THE STL METRO BY MIDDAY. CONVERGENCE WILL BE FAIRLY
WEAK BUT THERE SHOULD CERTAINLY BE ENOUGH INSTABILITY TO CARRY
CURRENT VCTS AT STL METRO TAF SITES IN THE EARLY AFTERNOON.
HOWEVER...HAVE DROPPED MENTION OF VCTS AT KCOU SINCE CONVERGENCE
ALONG SYNOPTIC FRONT SHOULD BE SOUTH OF THAT AREA. PREVAILING
CONDITIONS ACROSS THE AREA FOR THE AFTERNOON HOURS SHOULD BE SCT-
BKN CU 4-5KFT (WITH GREATEST CLOUD COVER NEAR/SOUTH OF COLD
FRONT)...WITH THIS CU FIELD QUICKLY DISSIPATING DURING THE EARLY
EVENING WITH LOSS OF HEATING AND AS THE DRIER POST-FRONTAL AIR
ADVECTS INTO THE AREA.
SPECIFICS FOR KSTL: SCATTERED CLOUDS AOA 4KFT ARE EXPECTED THIS
MORNING...WITH CU FIELD AOA 4KFT BECOMING SCT-BKN BY LATE MORNING
AND INTO THE AFTERNOON. HAVE CONTINUED VCTS IN THE 18-21 TIME
FRAME AS SYNOPTIC FRONT WILL BE PASSING AT THAT TIME. CU FIELD
SHOULD QUICKLY DISSIPATE HEADING INTO THE EARLY EVENING...WITH
A FEW CLOUDS AOA 10KFT OVERNIGHT AND INTO EARLY THURSDAY.
TRUETT
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...EXCESSIVE HEAT WARNING UNTIL 9 PM CDT THIS EVENING FOR CRAWFORD
MO-FRANKLIN MO-IRON MO-JEFFERSON MO-MADISON MO-REYNOLDS MO-
ST. CHARLES MO-ST. FRANCOIS MO-ST. LOUIS CITY MO-ST. LOUIS
MO-STE. GENEVIEVE MO-WASHINGTON MO.
IL...EXCESSIVE HEAT WARNING UNTIL 9 PM CDT THIS EVENING FOR CLINTON
IL-MADISON IL-MARION IL-MONROE IL-RANDOLPH IL-ST. CLAIR IL-
WASHINGTON IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
353 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...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1206 PM CDT WED JUL 29 2015
A COUPLE STRONGER WIND GUSTS UP TO AROUND 15MPH COULD MIX DOWN
INTO KOFK EARLY THIS AFTERNOON...HOWEVER LEAVING GUSTS OUT OF THE
TAF FOR NOW AS IT DOES NOT SEEM OVERLY LIKELY AND SHOULD NOT
PERSIST VERY LONG. OTHERWISE VFR CONDITIONS ARE EXPECTED THROUGH
THE PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...KG
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1229 PM CDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT WED JUL 29 2015
FOR THE MAJORITY OF THE CWA (ESPECIALLY NEB ZONES)...THIS SHOULD
BE A PRETTY STRAIGHTFORWARD NEXT 24 HOURS...WITH A CONTINUED
EXPECTATION OF DRY CONDITIONS AND SEASONABLY PLEASANT
TEMPS/DEWPOINTS...ALTHOUGH IT MAY BE A SOMEWHAT CLOUDIER DAY THAN
PREVIOUSLY THOUGHT. HOWEVER...THINGS GET A BIT TRICKIER SOUTHWARD
INTO KS ZONES (ESPECIALLY OUR BOTTOM-MOST 3 COUNTIES)...AS THERE
ARE SOME MODELS (FOR EXAMPLE THE GFS) SUGGESTING THAT THIS AREA
WILL BE BRUSHED BY THE FAR NORTHERN EDGES OF SOMEWHAT BETTER
SHOWER/WEAK THUNDERSTORM POTENTIAL THAT SHOULD MAINLY FOCUS JUST
SOUTH OF THE CWA...ESPECIALLY TONIGHT. THAT BEING SAID...OTHER
MODELS INCLUDING SIMULATED REFLECTIVITY FROM 4KM WRF/ARW RUNS
(INCLUDING THE OFTEN-RELIABLE NSSL WRF) ARE MORE SUPPORTIVE OF
THESE MEASURABLE RAIN CHANCES REMAINING JUST SOUTH OF THE
CWA...ALBEIT A RATHER CLOSE CALL. TO MAKE A LONG STORY
SHORTER...CONSIDERED ADDING A FORMAL SLIGHT CHANCE OF
SHOWERS/THUNDERSTORMS TO PARTS OF OUR KS COUNTIES FOR MUCH OF THIS
TIME FRAME...BUT GIVEN THE MIXED MESSAGES IN THE MODEL WORLD...AND
ALSO CONSIDERING THAT WE HAD BEEN CONSISTENTLY ADVERTISING A "DRY"
WEDNESDAY-WEDNESDAY NIGHT FORECAST CWA-WIDE THESE PAST FEW
DAYS...OPTED TO TAKE A "MIDDLE GROUND" APPROACH FOR NOW BY SIMPLY
INSERTING A "SLIGHT CHANCE OF SPRINKLES" INTO OUR FAR SOUTHERN
AREAS. THE INTENDED MESSAGE HERE IS THAT ALTHOUGH WE CONTINUE TO
DOWNPLAY PRECIP CHANCES...THE SPRINKLE MENTION BETTER IMPLIES THAT
CHANCES ARE NOT TRULY "ZERO" EITHER. OBVIOUSLY THE NEXT FEW SHIFTS
WILL HAVE TO MONITOR THE LATEST TRENDS JUST IN CASE PRECIP CHANCES
(POPS) AND POSSIBLY THUNDERSTORM POTENTIAL MAY NEED BEEFED UP A
BIT IN THIS TRICKY SOUTHERN AREA.
TAKING A LOOK AT THE HERE AND NOW AS OF 08Z/3AM: WE ARE ALREADY
IN THE MIDST OF A "CLOSE CALL" REGARDING SHOWER/THUNDERSTORM
CHANCES IN OUR FAR SOUTHERN CWA...AS A FAIRLY CONCENTRATED AXIS OF
SHOWERS /NON-SEVERE STORMS EXTENDING FROM NORTHEAST-CENTRAL KS IS
JUST BARELY REMAINING OUTSIDE OUR CWA FOR THE MOST PART. THIS
CONVECTION IS FOCUSED SLIGHTLY NORTH OF THE SYNOPTIC SURFACE COLD
FRONT POSITIONED OVER SOUTHERN AND EAST-CENTRAL KS...AND IS
LARGELY TIED TO AN AXIS OF LOW-MID LEVEL CONVERGENCE/FRONTOGENESIS
IN THE 850-700MB LAYER. NOT SURPRISINGLY...THE NORTHERN FRINGE OF
THIS CONVECTION IS ALIGNED ALMOST PERFECTLY WITH THE NORTHERN
FRINGES OF A VERY SLOWLY SOUTHWARD-SINKING ELEVATED INSTABILITY
AXIS...WHICH CLEARED THE VAST MAJORITY OF THE CWA BEHIND THE COLD
FRONTAL PASSAGE DURING THE PAST 24 HOURS. IN THE BIGGER PICTURE OF
THE MID-UPPER LEVELS...WATER VAPOR SATELLITE AND THE LATEST MODEL
DATA DEPICT LIMITED LARGE-SCALE FORCING OVER THE CENTRAL
PLAINS...AS THE LOCAL REGION IS SANDWICHED BETWEEN ANTICYCLONIC
FLOW ASSOCIATED WITH THE SOUTHERN PLAINS SUBTROPICAL HIGH...AND
THE SOUTHERN EDGES OF STRONGER WESTERLY FLOW ASSOCIATED WITH THE
VIGOROUS CLOSED LOW PRESSURE SYSTEM SLOWLY DEPARTING NORTHEAST
ACROSS THE MANITOBA/ONTARIO BORDER AREA. HOWEVER...THERE IS
EVIDENCE OF A SUBTLE DISTURBANCE PASSING NORTHEAST THROUGH
SOUTHWEST KS ASSOCIATED WITH A CLUSTER OF CONVECTION NEAR DODGE
CITY. WHILE 11-3.9 MICRON SATELLITE IMAGERY HAS REVEALED A LARGELY
CLEAR NIGHT THUS FAR OVER MUCH OF THE CWA...AT LEAST A THIN VEIL
OF HIGH CLOUDS IS INCREASINGLY SPREADING NORTHEAST INTO THE CWA FROM
THE SOUTHWEST KS CONVECTION. AT THE SURFACE...THINGS ARE LARGELY
PLAYING OUT AS EXPECTED TONIGHT...WITH THE SOUTHEASTERN REACH OF
BROAD HIGH PRESSURE CENTERED OVER THE NORTHERN ROCKIES PROVIDING
VERY LIGHT/MAINLY NORTHERLY BREEZES TO THE LOCAL AREA. THIS HIGH
PRESSURE AXIS...COMBINED WITH THE WELCOMED PRESENCE OF NOTICEABLY
DRIER AIR MARKED BY DEWPOINTS MAINLY IN THE 50S...HAS ALLOWED
TEMPS TO FALL SLIGHTLY BELOW LATE-JULY NORMALS IN MOST
AREAS...AND ULTIMATELY EXPECT OVERNIGHT LOWS TO RANGE FROM MID 50S
NORTHWEST...NEAR 60 CENTRAL AND MID-60S SOUTH.
NOW LOOKING AHEAD FORECAST-WISE:
EARLY THIS MORNING (THROUGH 7AM): OTHER THAN A CONTINUED GRADUAL
INCREASE IN HIGH CLOUDS SPREADING IN FROM THE SOUTHWEST...LITTLE
CHANGE FROM THE CURRENT SITUATION EXPECTED. GIVEN THAT IT APPEARS
THAT THE EXTREME SOUTHERN FRINGES OF THE CWA WILL CONTINUE TO
BARELY MISS OUT ON THE CENTRAL-NORTHEAST KS CONVECTION...WILL BE
REMOVING THE PREVIOUSLY-EXISTING SLIGHT CHANCE OF SHOWERS/STORMS
IN OUR FAR SOUTH FOR THE PRE-DAWN HOURS.
TODAY (7AM-7PM): SEE THE OPENING PARAGRAPH ABOVE FOR THE BASIC
REASONING BEHIND INTRODUCING SPRINKLE POTENTIAL INTO OUR FAR
SOUTHERN CWA IN KS. HOWEVER...BARRING AN UNEXPECTED NORTHWARD
SHIFT IN THE ONGOING EARLY MORNING CONVECTION IN CENTRAL KS...PLAN
ON MAINTAINING A THUNDERSTORM-FREE FORECAST GOING FORWARD INTO THE
OFFICIAL DAYTIME FORECAST PERIOD. AGAIN...FOR THE MAJORITY OF THE
CWA (ESSENTIALLY NEB ZONES)...CONFIDENCE IS STILL HIGH ENOUGH IN A
DRY DAY TO PRECLUDE EVEN A SPRINKLE MENTION. THAT BEING SAID
THOUGH...THE LAST FEW HRRR RUNS ACTUALLY DO TRY TO DROP A FEW
SPRINKLES OUT OF AN INCREASING MID LEVEL CLOUD DECK...BUT WILL
LARGELY IGNORE THIS FOR NOW WITH VERY LITTLE SUPPORT FROM OTHER
MODELS AND GIVEN THAT THIS LIMITED MOISTURE IS LARGELY AT/ABOVE
600MB. IN THE MID-UPPER LEVELS...SEASONABLY STRONG WESTERLY FLOW
PERSISTS OVERHEAD...WITH HINTS OF A SUBTLE DISTURBANCE PASSING
THROUGH THE CWA...POSSIBLY INCLUDING THE REMNANTS OF THE
AFOREMENTIONED SOUTHWEST KS ONE. MEANWHILE...THE NORTHERN EDGES
OF THE ELEVATED INSTABILITY AXIS OVER KS SHOULD LARGELY STALL OUT
JUST SOUTH OF THE CWA IN A WEST-T0-EAST FASHION. ALTHOUGH DO NOT
HAVE A GREAT FEEL FOR CLOUD COVER TODAY...BEEFED UP SKY COVER
PERCENTAGES SOLIDLY INTO PARTLY CLOUDY TERRITORY MOST AREAS FOR
MOST OF THE DAY...AND THERE COULD EASILY BE PERIODS OF MOSTLY
CLOUDY TOO...ESPECIALLY IF THE NAM IS CORRECT IN DEPICTING A
FAIRLY WIDESPREAD COVERAGE OF MID-HIGH CLOUDS DEVELOPING IN
RESPONSE TO THE AFOREMENTIONED WEAK DISTURBANCE(S) PASSING
THROUGH. AT THE SURFACE...BROAD HIGH PRESSURE WILL PASS EASTWARD
OVER THE HEART OF THE CWA...PROMOTING NOT ONLY LIGHT BREEZES THAT
WILL LARGELY AVERAGE UNDER 10 MPH...BUT ALSO A GRADUALLY VARYING
DIRECTION AS MANY PLACES SEE A TRANSITION FROM NORTHERLY TO
EASTERLY TO SOUTHERLY BY LATE IN THE DAY. TEMP-WISE...WOULD NOT BE
SURPRISED IF INCREASING CLOUDS HOLD THINGS BACK A TOUCH AND DID
DROP SOME AREAS (INCLUDING TRI-CITIES) 1-2 DEGREES FROM PREVIOUS
FORECAST...BUT OVERALL STILL CALLING FOR MOST OF THE CWA TO TOP
OUT IN THE 82-85 RANGE...WHICH COMBINED WITH LIGHT WIND AND
DEWPOINTS LARGELY IN THE 50S SHOULD MAKE FOR A VERY COMFORTABLE
LATE JULY DAY.
TONIGHT (7PM-7AM): AGAIN...SEE OPENING PARAGRAPH FOR FURTHER
INSIGHT INTO THE DECISION TO ADD SPRINKLE POSSIBILITY INTO PARTS
OF KS ZONES. ALTHOUGH MODEL DISCREPANCY CONTINUES REGARDING
NORTHERN KS PRECIP POTENTIAL...ITS WORTH NOTING THAT THE VERY
LATEST 06Z NAM HAS BACKED OFF THE NORTHWARD EXTENT OF
SHOWER/THUNDERSTORM POTENTIAL...NOW KEEPING OVERNIGHT CONVECTION
JUST SOUTH OF THE CWA (MUCH THE SAME PLACEMENT AS THE ONGOING
ACTIVITY). IN THE MID-UPPER LEVELS TONIGHT...FLOW OVER THE CWA
STARTS TO TURN EVER-SO-SLIGHTLY NORTHWESTERLY...IN RESPONSE TO
THE SOUTHERN PLAINS RIDGE STARTING TO RETROGRADE WESTWARD A BIT.
WHILE FAIRLY SUBTLE LOW-MID LEVEL LIFT/CONVERGENCE IS EXPECTED TO
PROMOTE "SOME" COVERAGE OF SHOWERS/STORMS MAINLY JUST SOUTH OF THE
CWA...THE VAST MAJORITY OF THE LOCAL AREA SHOULD REMAIN VOID OF
EVEN SPRINKLES...WITH A LIKELY DECREASE IN MID-HIGH LEVEL CLOUDS
AS WELL FROM THE DAYTIME...THUS PROMOTING MOSTLY CLEAR SKIES
ESPECIALLY NORTH OF THE STATE LINE. AT THE SURFACE...LIGHT BREEZES
WILL CONTINUE IN THE PRESENCE OF BROAD HIGH PRESSURE...BUT LIKELY
TAKING ON MORE OF A SOUTHERLY AND/OR WESTERLY COMPONENT. ALL IN
ALL...LOW TEMPS ACROSS MOST OF THE CWA MAY END UP BEING VERY
SIMILAR TO THOSE OBSERVED THIS MORNING...BUT FOR NOW WILL AIM MOST
PLACES VERY SLIGHTLY WARMER...WITH MOST OF THE CWA BOTTOMING OUT
SOMEWHERE IN THE 58-63 RANGE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED JUL 29 2015
AFTER A VERY NICE WEDNESDAY WE WILL WARM RIGHT BACK UP INTO THE
UPPER 80S TO LOWER 90S FOR THURSDAY THROUGH THE WEEKEND AND INTO
NEXT MONDAY...BEFORE PERHAPS ANOTHER COOL DOWN NEXT TUESDAY. WE DO
HAVE SEVERAL RAIN CHANCES...BUT CONFIDENCE IN SEEING PRECIPITATION
IS NOT THAT HIGH ON ANY GIVEN DAY. MOST LOCATIONS WILL LIKELY END UP
DRY THROUGH FRIDAY...BUT WE WILL SEE AT LEAST A FEW MORE CHANCES OF
RAIN THEREAFTER.
THURSDAY AND FRIDAY...THE HUMIDITY WILL BEGIN TO WORK BACK INTO THE
REGION. DEWPOINTS WILL RISE FROM THEIR LOW POINT IN THE LOWER 50S
TODAY...TO AROUND 60 ON THURSDAY...AND INTO THE MID 60S BY FRIDAY.
THE SFC WIND WILL BE FAIRLY LIGHT...BUT IS EXPECTED TO BECOME
GENERALLY SOUTHERLY...WHICH WILL HELP TO WARM THINGS UP A COUPLE
DEGREES BACK TO AROUND NORMAL IN THE UPPER 80S TO AROUND 90. THE
UPPER RIDGE OVER THE SOUTHERN PLAINS WILL RETROGRADE BACK TO THE
WEST AND SET UP OVER THE DESERT SOUTHWEST. IN OUR AREA THERE WILL BE
AN AREA OF WEAK SFC CONVERGENCE ACROSS OUR NORTHERN AND EASTERN
ZONES FRIDAY AFTERNOON THAT COULD POP A FEW ISOLATED THUNDERSTORMS
BASED ON THE 00Z NAM AND 00Z GFS. CONFIDENCE IS LOW AND CONVECTION
WOULD LIKELY BE VERY HIT AND MISS WITH MOST FOLKS LIKELY MISSING OUT
ON IT.
SATURDAY THROUGH MONDAY...NORTHWESTERLY FLOW ALOFT WILL SEND US A
FEW SHORTWAVES AND SUBSEQUENT THUNDERSTORM CHANCES. ONE SUCH
SHORTWAVE IS EVIDENT IN THE 00Z GFS AND 00Z ECMWF SATURDAY
AFTERNOON/EVENING. THEREFORE...WILL THROW SOME CHANCE POPS IN THE
FORECAST WITH THE HIGHEST POPS BEING ACROSS NORTHERN AND EASTERN
ZONES. OVERALL...AT LEAST THE WAY IT LOOK RIGHT NOW...PRECIPITATION
CHANCES WILL STILL BE FAIRLY LOW AT LESS THAN 50/50. WE SHOULD BE IN
BETWEEN SHORTWAVES ON SUNDAY SO CONFIDENCE IN DRY WEATHER IS FAIRLY
GOOD FOR SUNDAY. THE NEXT SHORTWAVE ENTERS THE PICTURE ON MONDAY BUT
FORECAST MODELS DIFFER ON THE SPEED OF THE ASSOCIATED FRONT. GIVEN
THE EXPECTATION OF HAVING SOME UPPER LEVEL SUPPORT IN THE GENERAL
AREA FROM THIS UPPER WAVE...WILL CALL FOR CHANCE POPS. TEMPERATURES
WILL REMAIN NEAR NORMAL DURING THIS STRETCH...OR GENERALLY IN THE
UPPER 80S TO LOWER 90S.
TUESDAY...CONFIDENCE IS PRETTY LOW THIS FAR OUT GIVEN THE
NORTHWESTERLY FLOW REGIME. THEREFORE...WILL STICK WITH THE
SUPERBLEND OF ALL MODELS...WHICH GIVES US A SMALL CHANCE OF
PRECIPITATION AND SLIGHTLY COOLER TEMPERATURES WITH HIGHS IN THE MID
TO UPPER 80S.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1228 PM CDT WED JUL 29 2015
VFR CONDITIONS ARE FORECAST THROUGH THE TAF PERIOD.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM...WESELY
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
642 AM CDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT WED JUL 29 2015
FOR THE MAJORITY OF THE CWA (ESPECIALLY NEB ZONES)...THIS SHOULD
BE A PRETTY STRAIGHTFORWARD NEXT 24 HOURS...WITH A CONTINUED
EXPECTATION OF DRY CONDITIONS AND SEASONABLY PLEASANT
TEMPS/DEWPOINTS...ALTHOUGH IT MAY BE A SOMEWHAT CLOUDIER DAY THAN
PREVIOUSLY THOUGHT. HOWEVER...THINGS GET A BIT TRICKIER SOUTHWARD
INTO KS ZONES (ESPECIALLY OUR BOTTOM-MOST 3 COUNTIES)...AS THERE
ARE SOME MODELS (FOR EXAMPLE THE GFS) SUGGESTING THAT THIS AREA
WILL BE BRUSHED BY THE FAR NORTHERN EDGES OF SOMEWHAT BETTER
SHOWER/WEAK THUNDERSTORM POTENTIAL THAT SHOULD MAINLY FOCUS JUST
SOUTH OF THE CWA...ESPECIALLY TONIGHT. THAT BEING SAID...OTHER
MODELS INCLUDING SIMULATED REFLECTIVITY FROM 4KM WRF/ARW RUNS
(INCLUDING THE OFTEN-RELIABLE NSSL WRF) ARE MORE SUPPORTIVE OF
THESE MEASURABLE RAIN CHANCES REMAINING JUST SOUTH OF THE
CWA...ALBEIT A RATHER CLOSE CALL. TO MAKE A LONG STORY
SHORTER...CONSIDERED ADDING A FORMAL SLIGHT CHANCE OF
SHOWERS/THUNDERSTORMS TO PARTS OF OUR KS COUNTIES FOR MUCH OF THIS
TIME FRAME...BUT GIVEN THE MIXED MESSAGES IN THE MODEL WORLD...AND
ALSO CONSIDERING THAT WE HAD BEEN CONSISTENTLY ADVERTISING A "DRY"
WEDNESDAY-WEDNESDAY NIGHT FORECAST CWA-WIDE THESE PAST FEW
DAYS...OPTED TO TAKE A "MIDDLE GROUND" APPROACH FOR NOW BY SIMPLY
INSERTING A "SLIGHT CHANCE OF SPRINKLES" INTO OUR FAR SOUTHERN
AREAS. THE INTENDED MESSAGE HERE IS THAT ALTHOUGH WE CONTINUE TO
DOWNPLAY PRECIP CHANCES...THE SPRINKLE MENTION BETTER IMPLIES THAT
CHANCES ARE NOT TRULY "ZERO" EITHER. OBVIOUSLY THE NEXT FEW SHIFTS
WILL HAVE TO MONITOR THE LATEST TRENDS JUST IN CASE PRECIP CHANCES
(POPS) AND POSSIBLY THUNDERSTORM POTENTIAL MAY NEED BEEFED UP A
BIT IN THIS TRICKY SOUTHERN AREA.
TAKING A LOOK AT THE HERE AND NOW AS OF 08Z/3AM: WE ARE ALREADY
IN THE MIDST OF A "CLOSE CALL" REGARDING SHOWER/THUNDERSTORM
CHANCES IN OUR FAR SOUTHERN CWA...AS A FAIRLY CONCENTRATED AXIS OF
SHOWERS /NON-SEVERE STORMS EXTENDING FROM NORTHEAST-CENTRAL KS IS
JUST BARELY REMAINING OUTSIDE OUR CWA FOR THE MOST PART. THIS
CONVECTION IS FOCUSED SLIGHTLY NORTH OF THE SYNOPTIC SURFACE COLD
FRONT POSITIONED OVER SOUTHERN AND EAST-CENTRAL KS...AND IS
LARGELY TIED TO AN AXIS OF LOW-MID LEVEL CONVERGENCE/FRONTOGENESIS
IN THE 850-700MB LAYER. NOT SURPRISINGLY...THE NORTHERN FRINGE OF
THIS CONVECTION IS ALIGNED ALMOST PERFECTLY WITH THE NORTHERN
FRINGES OF A VERY SLOWLY SOUTHWARD-SINKING ELEVATED INSTABILITY
AXIS...WHICH CLEARED THE VAST MAJORITY OF THE CWA BEHIND THE COLD
FRONTAL PASSAGE DURING THE PAST 24 HOURS. IN THE BIGGER PICTURE OF
THE MID-UPPER LEVELS...WATER VAPOR SATELLITE AND THE LATEST MODEL
DATA DEPICT LIMITED LARGE-SCALE FORCING OVER THE CENTRAL
PLAINS...AS THE LOCAL REGION IS SANDWICHED BETWEEN ANTICYCLONIC
FLOW ASSOCIATED WITH THE SOUTHERN PLAINS SUBTROPICAL HIGH...AND
THE SOUTHERN EDGES OF STRONGER WESTERLY FLOW ASSOCIATED WITH THE
VIGOROUS CLOSED LOW PRESSURE SYSTEM SLOWLY DEPARTING NORTHEAST
ACROSS THE MANITOBA/ONTARIO BORDER AREA. HOWEVER...THERE IS
EVIDENCE OF A SUBTLE DISTURBANCE PASSING NORTHEAST THROUGH
SOUTHWEST KS ASSOCIATED WITH A CLUSTER OF CONVECTION NEAR DODGE
CITY. WHILE 11-3.9 MICRON SATELLITE IMAGERY HAS REVEALED A LARGELY
CLEAR NIGHT THUS FAR OVER MUCH OF THE CWA...AT LEAST A THIN VEIL
OF HIGH CLOUDS IS INCREASINGLY SPREADING NORTHEAST INTO THE CWA FROM
THE SOUTHWEST KS CONVECTION. AT THE SURFACE...THINGS ARE LARGELY
PLAYING OUT AS EXPECTED TONIGHT...WITH THE SOUTHEASTERN REACH OF
BROAD HIGH PRESSURE CENTERED OVER THE NORTHERN ROCKIES PROVIDING
VERY LIGHT/MAINLY NORTHERLY BREEZES TO THE LOCAL AREA. THIS HIGH
PRESSURE AXIS...COMBINED WITH THE WELCOMED PRESENCE OF NOTICEABLY
DRIER AIR MARKED BY DEWPOINTS MAINLY IN THE 50S...HAS ALLOWED
TEMPS TO FALL SLIGHTLY BELOW LATE-JULY NORMALS IN MOST
AREAS...AND ULTIMATELY EXPECT OVERNIGHT LOWS TO RANGE FROM MID 50S
NORTHWEST...NEAR 60 CENTRAL AND MID-60S SOUTH.
NOW LOOKING AHEAD FORECAST-WISE:
EARLY THIS MORNING (THROUGH 7AM): OTHER THAN A CONTINUED GRADUAL
INCREASE IN HIGH CLOUDS SPREADING IN FROM THE SOUTHWEST...LITTLE
CHANGE FROM THE CURRENT SITUATION EXPECTED. GIVEN THAT IT APPEARS
THAT THE EXTREME SOUTHERN FRINGES OF THE CWA WILL CONTINUE TO
BARELY MISS OUT ON THE CENTRAL-NORTHEAST KS CONVECTION...WILL BE
REMOVING THE PREVIOUSLY-EXISTING SLIGHT CHANCE OF SHOWERS/STORMS
IN OUR FAR SOUTH FOR THE PRE-DAWN HOURS.
TODAY (7AM-7PM): SEE THE OPENING PARAGRAPH ABOVE FOR THE BASIC
REASONING BEHIND INTRODUCING SPRINKLE POTENTIAL INTO OUR FAR
SOUTHERN CWA IN KS. HOWEVER...BARRING AN UNEXPECTED NORTHWARD
SHIFT IN THE ONGOING EARLY MORNING CONVECTION IN CENTRAL KS...PLAN
ON MAINTAINING A THUNDERSTORM-FREE FORECAST GOING FORWARD INTO THE
OFFICIAL DAYTIME FORECAST PERIOD. AGAIN...FOR THE MAJORITY OF THE
CWA (ESSENTIALLY NEB ZONES)...CONFIDENCE IS STILL HIGH ENOUGH IN A
DRY DAY TO PRECLUDE EVEN A SPRINKLE MENTION. THAT BEING SAID
THOUGH...THE LAST FEW HRRR RUNS ACTUALLY DO TRY TO DROP A FEW
SPRINKLES OUT OF AN INCREASING MID LEVEL CLOUD DECK...BUT WILL
LARGELY IGNORE THIS FOR NOW WITH VERY LITTLE SUPPORT FROM OTHER
MODELS AND GIVEN THAT THIS LIMITED MOISTURE IS LARGELY AT/ABOVE
600MB. IN THE MID-UPPER LEVELS...SEASONABLY STRONG WESTERLY FLOW
PERSISTS OVERHEAD...WITH HINTS OF A SUBTLE DISTURBANCE PASSING
THROUGH THE CWA...POSSIBLY INCLUDING THE REMNANTS OF THE
AFOREMENTIONED SOUTHWEST KS ONE. MEANWHILE...THE NORTHERN EDGES
OF THE ELEVATED INSTABILITY AXIS OVER KS SHOULD LARGELY STALL OUT
JUST SOUTH OF THE CWA IN A WEST-T0-EAST FASHION. ALTHOUGH DO NOT
HAVE A GREAT FEEL FOR CLOUD COVER TODAY...BEEFED UP SKY COVER
PERCENTAGES SOLIDLY INTO PARTLY CLOUDY TERRITORY MOST AREAS FOR
MOST OF THE DAY...AND THERE COULD EASILY BE PERIODS OF MOSTLY
CLOUDY TOO...ESPECIALLY IF THE NAM IS CORRECT IN DEPICTING A
FAIRLY WIDESPREAD COVERAGE OF MID-HIGH CLOUDS DEVELOPING IN
RESPONSE TO THE AFOREMENTIONED WEAK DISTURBANCE(S) PASSING
THROUGH. AT THE SURFACE...BROAD HIGH PRESSURE WILL PASS EASTWARD
OVER THE HEART OF THE CWA...PROMOTING NOT ONLY LIGHT BREEZES THAT
WILL LARGELY AVERAGE UNDER 10 MPH...BUT ALSO A GRADUALLY VARYING
DIRECTION AS MANY PLACES SEE A TRANSITION FROM NORTHERLY TO
EASTERLY TO SOUTHERLY BY LATE IN THE DAY. TEMP-WISE...WOULD NOT BE
SURPRISED IF INCREASING CLOUDS HOLD THINGS BACK A TOUCH AND DID
DROP SOME AREAS (INCLUDING TRI-CITIES) 1-2 DEGREES FROM PREVIOUS
FORECAST...BUT OVERALL STILL CALLING FOR MOST OF THE CWA TO TOP
OUT IN THE 82-85 RANGE...WHICH COMBINED WITH LIGHT WIND AND
DEWPOINTS LARGELY IN THE 50S SHOULD MAKE FOR A VERY COMFORTABLE
LATE JULY DAY.
TONIGHT (7PM-7AM): AGAIN...SEE OPENING PARAGRAPH FOR FURTHER
INSIGHT INTO THE DECISION TO ADD SPRINKLE POSSIBILITY INTO PARTS
OF KS ZONES. ALTHOUGH MODEL DISCREPANCY CONTINUES REGARDING
NORTHERN KS PRECIP POTENTIAL...ITS WORTH NOTING THAT THE VERY
LATEST 06Z NAM HAS BACKED OFF THE NORTHWARD EXTENT OF
SHOWER/THUNDERSTORM POTENTIAL...NOW KEEPING OVERNIGHT CONVECTION
JUST SOUTH OF THE CWA (MUCH THE SAME PLACEMENT AS THE ONGOING
ACTIVITY). IN THE MID-UPPER LEVELS TONIGHT...FLOW OVER THE CWA
STARTS TO TURN EVER-SO-SLIGHTLY NORTHWESTERLY...IN RESPONSE TO
THE SOUTHERN PLAINS RIDGE STARTING TO RETROGRADE WESTWARD A BIT.
WHILE FAIRLY SUBTLE LOW-MID LEVEL LIFT/CONVERGENCE IS EXPECTED TO
PROMOTE "SOME" COVERAGE OF SHOWERS/STORMS MAINLY JUST SOUTH OF THE
CWA...THE VAST MAJORITY OF THE LOCAL AREA SHOULD REMAIN VOID OF
EVEN SPRINKLES...WITH A LIKELY DECREASE IN MID-HIGH LEVEL CLOUDS
AS WELL FROM THE DAYTIME...THUS PROMOTING MOSTLY CLEAR SKIES
ESPECIALLY NORTH OF THE STATE LINE. AT THE SURFACE...LIGHT BREEZES
WILL CONTINUE IN THE PRESENCE OF BROAD HIGH PRESSURE...BUT LIKELY
TAKING ON MORE OF A SOUTHERLY AND/OR WESTERLY COMPONENT. ALL IN
ALL...LOW TEMPS ACROSS MOST OF THE CWA MAY END UP BEING VERY
SIMILAR TO THOSE OBSERVED THIS MORNING...BUT FOR NOW WILL AIM MOST
PLACES VERY SLIGHTLY WARMER...WITH MOST OF THE CWA BOTTOMING OUT
SOMEWHERE IN THE 58-63 RANGE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED JUL 29 2015
AFTER A VERY NICE WEDNESDAY WE WILL WARM RIGHT BACK UP INTO THE
UPPER 80S TO LOWER 90S FOR THURSDAY THROUGH THE WEEKEND AND INTO
NEXT MONDAY...BEFORE PERHAPS ANOTHER COOL DOWN NEXT TUESDAY. WE DO
HAVE SEVERAL RAIN CHANCES...BUT CONFIDENCE IN SEEING PRECIPITATION
IS NOT THAT HIGH ON ANY GIVEN DAY. MOST LOCATIONS WILL LIKELY END UP
DRY THROUGH FRIDAY...BUT WE WILL SEE AT LEAST A FEW MORE CHANCES OF
RAIN THEREAFTER.
THURSDAY AND FRIDAY...THE HUMIDITY WILL BEGIN TO WORK BACK INTO THE
REGION. DEWPOINTS WILL RISE FROM THEIR LOW POINT IN THE LOWER 50S
TODAY...TO AROUND 60 ON THURSDAY...AND INTO THE MID 60S BY FRIDAY.
THE SFC WIND WILL BE FAIRLY LIGHT...BUT IS EXPECTED TO BECOME
GENERALLY SOUTHERLY...WHICH WILL HELP TO WARM THINGS UP A COUPLE
DEGREES BACK TO AROUND NORMAL IN THE UPPER 80S TO AROUND 90. THE
UPPER RIDGE OVER THE SOUTHERN PLAINS WILL RETROGRADE BACK TO THE
WEST AND SET UP OVER THE DESERT SOUTHWEST. IN OUR AREA THERE WILL BE
AN AREA OF WEAK SFC CONVERGENCE ACROSS OUR NORTHERN AND EASTERN
ZONES FRIDAY AFTERNOON THAT COULD POP A FEW ISOLATED THUNDERSTORMS
BASED ON THE 00Z NAM AND 00Z GFS. CONFIDENCE IS LOW AND CONVECTION
WOULD LIKELY BE VERY HIT AND MISS WITH MOST FOLKS LIKELY MISSING OUT
ON IT.
SATURDAY THROUGH MONDAY...NORTHWESTERLY FLOW ALOFT WILL SEND US A
FEW SHORTWAVES AND SUBSEQUENT THUNDERSTORM CHANCES. ONE SUCH
SHORTWAVE IS EVIDENT IN THE 00Z GFS AND 00Z ECMWF SATURDAY
AFTERNOON/EVENING. THEREFORE...WILL THROW SOME CHANCE POPS IN THE
FORECAST WITH THE HIGHEST POPS BEING ACROSS NORTHERN AND EASTERN
ZONES. OVERALL...AT LEAST THE WAY IT LOOK RIGHT NOW...PRECIPITATION
CHANCES WILL STILL BE FAIRLY LOW AT LESS THAN 50/50. WE SHOULD BE IN
BETWEEN SHORTWAVES ON SUNDAY SO CONFIDENCE IN DRY WEATHER IS FAIRLY
GOOD FOR SUNDAY. THE NEXT SHORTWAVE ENTERS THE PICTURE ON MONDAY BUT
FORECAST MODELS DIFFER ON THE SPEED OF THE ASSOCIATED FRONT. GIVEN
THE EXPECTATION OF HAVING SOME UPPER LEVEL SUPPORT IN THE GENERAL
AREA FROM THIS UPPER WAVE...WILL CALL FOR CHANCE POPS. TEMPERATURES
WILL REMAIN NEAR NORMAL DURING THIS STRETCH...OR GENERALLY IN THE
UPPER 80S TO LOWER 90S.
TUESDAY...CONFIDENCE IS PRETTY LOW THIS FAR OUT GIVEN THE
NORTHWESTERLY FLOW REGIME. THEREFORE...WILL STICK WITH THE
SUPERBLEND OF ALL MODELS...WHICH GIVES US A SMALL CHANCE OF
PRECIPITATION AND SLIGHTLY COOLER TEMPERATURES WITH HIGHS IN THE MID
TO UPPER 80S.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 642 AM CDT WED JUL 29 2015
BARRING UNEXPECTED DEVELOPMENTS...THIS SHOULD BE A VERY QUIET 24
HOURS IN THE AVIATION DEPARTMENT. FIRST OFF...NOT ANTICIPATING ANY
PRECIPITATION/THUNDERSTORMS. CONFIDENCE IS ACTUALLY VERY HIGH IN
VFR CEILING AND VISIBILITY...ALTHOUGH MUCH OF THE DAY WILL LIKELY
FEATURE A DECENT AMOUNT OF MID-HIGH CLOUD COVER. AS FOR SURFACE
WIND...THE VAST MAJORITY OF THE PERIOD SHOULD FEATURE SPEEDS
AT/BELOW 6KT...AND WITH A HIGH PRESSURE AXIS CENTERED OVER THE
REGION...DIRECTION WILL BE RATHER VARIABLE IN NATURE TODAY BEFORE
POSSIBLY BECOMING A BIT MORE CONSISTENT FROM THE SOUTHWEST
TONIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM...WESELY
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
400 AM CDT WED JUL 29 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT WED JUL 29 2015
FOR THE MAJORITY OF THE CWA (ESPECIALLY NEB ZONES)...THIS SHOULD
BE A PRETTY STRAIGHTFORWARD NEXT 24 HOURS...WITH A CONTINUED
EXPECTATION OF DRY CONDITIONS AND SEASONABLY PLEASANT
TEMPS/DEWPOINTS...ALTHOUGH IT MAY BE A SOMEWHAT CLOUDIER DAY THAN
PREVIOUSLY THOUGHT. HOWEVER...THINGS GET A BIT TRICKIER SOUTHWARD
INTO KS ZONES (ESPECIALLY OUR BOTTOM-MOST 3 COUNTIES)...AS THERE
ARE SOME MODELS (FOR EXAMPLE THE GFS) SUGGESTING THAT THIS AREA
WILL BE BRUSHED BY THE FAR NORTHERN EDGES OF SOMEWHAT BETTER
SHOWER/WEAK THUNDERSTORM POTENTIAL THAT SHOULD MAINLY FOCUS JUST
SOUTH OF THE CWA...ESPECIALLY TONIGHT. THAT BEING SAID...OTHER
MODELS INCLUDING SIMULATED REFLECTIVITY FROM 4KM WRF/ARW RUNS
(INCLUDING THE OFTEN-RELIABLE NSSL WRF) ARE MORE SUPPORTIVE OF
THESE MEASURABLE RAIN CHANCES REMAINING JUST SOUTH OF THE
CWA...ALBEIT A RATHER CLOSE CALL. TO MAKE A LONG STORY
SHORTER...CONSIDERED ADDING A FORMAL SLIGHT CHANCE OF
SHOWERS/THUNDERSTORMS TO PARTS OF OUR KS COUNTIES FOR MUCH OF THIS
TIME FRAME...BUT GIVEN THE MIXED MESSAGES IN THE MODEL WORLD...AND
ALSO CONSIDERING THAT WE HAD BEEN CONSISTENTLY ADVERTISING A "DRY"
WEDNESDAY-WEDNESDAY NIGHT FORECAST CWA-WIDE THESE PAST FEW
DAYS...OPTED TO TAKE A "MIDDLE GROUND" APPROACH FOR NOW BY SIMPLY
INSERTING A "SLIGHT CHANCE OF SPRINKLES" INTO OUR FAR SOUTHERN
AREAS. THE INTENDED MESSAGE HERE IS THAT ALTHOUGH WE CONTINUE TO
DOWNPLAY PRECIP CHANCES...THE SPRINKLE MENTION BETTER IMPLIES THAT
CHANCES ARE NOT TRULY "ZERO" EITHER. OBVIOUSLY THE NEXT FEW SHIFTS
WILL HAVE TO MONITOR THE LATEST TRENDS JUST IN CASE PRECIP CHANCES
(POPS) AND POSSIBLY THUNDERSTORM POTENTIAL MAY NEED BEEFED UP A
BIT IN THIS TRICKY SOUTHERN AREA.
TAKING A LOOK AT THE HERE AND NOW AS OF 08Z/3AM: WE ARE ALREADY
IN THE MIDST OF A "CLOSE CALL" REGARDING SHOWER/THUNDERSTORM
CHANCES IN OUR FAR SOUTHERN CWA...AS A FAIRLY CONCENTRATED AXIS OF
SHOWERS /NON-SEVERE STORMS EXTENDING FROM NORTHEAST-CENTRAL KS IS
JUST BARELY REMAINING OUTSIDE OUR CWA FOR THE MOST PART. THIS
CONVECTION IS FOCUSED SLIGHTLY NORTH OF THE SYNOPTIC SURFACE COLD
FRONT POSITIONED OVER SOUTHERN AND EAST-CENTRAL KS...AND IS
LARGELY TIED TO AN AXIS OF LOW-MID LEVEL CONVERGENCE/FRONTOGENESIS
IN THE 850-700MB LAYER. NOT SURPRISINGLY...THE NORTHERN FRINGE OF
THIS CONVECTION IS ALIGNED ALMOST PERFECTLY WITH THE NORTHERN
FRINGES OF A VERY SLOWLY SOUTHWARD-SINKING ELEVATED INSTABILITY
AXIS...WHICH CLEARED THE VAST MAJORITY OF THE CWA BEHIND THE COLD
FRONTAL PASSAGE DURING THE PAST 24 HOURS. IN THE BIGGER PICTURE OF
THE MID-UPPER LEVELS...WATER VAPOR SATELLITE AND THE LATEST MODEL
DATA DEPICT LIMITED LARGE-SCALE FORCING OVER THE CENTRAL
PLAINS...AS THE LOCAL REGION IS SANDWICHED BETWEEN ANTICYCLONIC
FLOW ASSOCIATED WITH THE SOUTHERN PLAINS SUBTROPICAL HIGH...AND
THE SOUTHERN EDGES OF STRONGER WESTERLY FLOW ASSOCIATED WITH THE
VIGOROUS CLOSED LOW PRESSURE SYSTEM SLOWLY DEPARTING NORTHEAST
ACROSS THE MANITOBA/ONTARIO BORDER AREA. HOWEVER...THERE IS
EVIDENCE OF A SUBTLE DISTURBANCE PASSING NORTHEAST THROUGH
SOUTHWEST KS ASSOCIATED WITH A CLUSTER OF CONVECTION NEAR DODGE
CITY. WHILE 11-3.9 MICRON SATELLITE IMAGERY HAS REVEALED A LARGELY
CLEAR NIGHT THUS FAR OVER MUCH OF THE CWA...AT LEAST A THIN VEIL
OF HIGH CLOUDS IS INCREASINGLY SPREADING NORTHEAST INTO THE CWA FROM
THE SOUTHWEST KS CONVECTION. AT THE SURFACE...THINGS ARE LARGELY
PLAYING OUT AS EXPECTED TONIGHT...WITH THE SOUTHEASTERN REACH OF
BROAD HIGH PRESSURE CENTERED OVER THE NORTHERN ROCKIES PROVIDING
VERY LIGHT/MAINLY NORTHERLY BREEZES TO THE LOCAL AREA. THIS HIGH
PRESSURE AXIS...COMBINED WITH THE WELCOMED PRESENCE OF NOTICEABLY
DRIER AIR MARKED BY DEWPOINTS MAINLY IN THE 50S...HAS ALLOWED
TEMPS TO FALL SLIGHTLY BELOW LATE-JULY NORMALS IN MOST
AREAS...AND ULTIMATELY EXPECT OVERNIGHT LOWS TO RANGE FROM MID 50S
NORTHWEST...NEAR 60 CENTRAL AND MID-60S SOUTH.
NOW LOOKING AHEAD FORECAST-WISE:
EARLY THIS MORNING (THROUGH 7AM): OTHER THAN A CONTINUED GRADUAL
INCREASE IN HIGH CLOUDS SPREADING IN FROM THE SOUTHWEST...LITTLE
CHANGE FROM THE CURRENT SITUATION EXPECTED. GIVEN THAT IT APPEARS
THAT THE EXTREME SOUTHERN FRINGES OF THE CWA WILL CONTINUE TO
BARELY MISS OUT ON THE CENTRAL-NORTHEAST KS CONVECTION...WILL BE
REMOVING THE PREVIOUSLY-EXISTING SLIGHT CHANCE OF SHOWERS/STORMS
IN OUR FAR SOUTH FOR THE PRE-DAWN HOURS.
TODAY (7AM-7PM): SEE THE OPENING PARAGRAPH ABOVE FOR THE BASIC
REASONING BEHIND INTRODUCING SPRINKLE POTENTIAL INTO OUR FAR
SOUTHERN CWA IN KS. HOWEVER...BARRING AN UNEXPECTED NORTHWARD
SHIFT IN THE ONGOING EARLY MORNING CONVECTION IN CENTRAL KS...PLAN
ON MAINTAINING A THUNDERSTORM-FREE FORECAST GOING FORWARD INTO THE
OFFICIAL DAYTIME FORECAST PERIOD. AGAIN...FOR THE MAJORITY OF THE
CWA (ESSENTIALLY NEB ZONES)...CONFIDENCE IS STILL HIGH ENOUGH IN A
DRY DAY TO PRECLUDE EVEN A SPRINKLE MENTION. THAT BEING SAID
THOUGH...THE LAST FEW HRRR RUNS ACTUALLY DO TRY TO DROP A FEW
SPRINKLES OUT OF AN INCREASING MID LEVEL CLOUD DECK...BUT WILL
LARGELY IGNORE THIS FOR NOW WITH VERY LITTLE SUPPORT FROM OTHER
MODELS AND GIVEN THAT THIS LIMITED MOISTURE IS LARGELY AT/ABOVE
600MB. IN THE MID-UPPER LEVELS...SEASONABLY STRONG WESTERLY FLOW
PERSISTS OVERHEAD...WITH HINTS OF A SUBTLE DISTURBANCE PASSING
THROUGH THE CWA...POSSIBLY INCLUDING THE REMNANTS OF THE
AFOREMENTIONED SOUTHWEST KS ONE. MEANWHILE...THE NORTHERN EDGES
OF THE ELEVATED INSTABILITY AXIS OVER KS SHOULD LARGELY STALL OUT
JUST SOUTH OF THE CWA IN A WEST-T0-EAST FASHION. ALTHOUGH DO NOT
HAVE A GREAT FEEL FOR CLOUD COVER TODAY...BEEFED UP SKY COVER
PERCENTAGES SOLIDLY INTO PARTLY CLOUDY TERRITORY MOST AREAS FOR
MOST OF THE DAY...AND THERE COULD EASILY BE PERIODS OF MOSTLY
CLOUDY TOO...ESPECIALLY IF THE NAM IS CORRECT IN DEPICTING A
FAIRLY WIDESPREAD COVERAGE OF MID-HIGH CLOUDS DEVELOPING IN
RESPONSE TO THE AFOREMENTIONED WEAK DISTURBANCE(S) PASSING
THROUGH. AT THE SURFACE...BROAD HIGH PRESSURE WILL PASS EASTWARD
OVER THE HEART OF THE CWA...PROMOTING NOT ONLY LIGHT BREEZES THAT
WILL LARGELY AVERAGE UNDER 10 MPH...BUT ALSO A GRADUALLY VARYING
DIRECTION AS MANY PLACES SEE A TRANSITION FROM NORTHERLY TO
EASTERLY TO SOUTHERLY BY LATE IN THE DAY. TEMP-WISE...WOULD NOT BE
SURPRISED IF INCREASING CLOUDS HOLD THINGS BACK A TOUCH AND DID
DROP SOME AREAS (INCLUDING TRI-CITIES) 1-2 DEGREES FROM PREVIOUS
FORECAST...BUT OVERALL STILL CALLING FOR MOST OF THE CWA TO TOP
OUT IN THE 82-85 RANGE...WHICH COMBINED WITH LIGHT WIND AND
DEWPOINTS LARGELY IN THE 50S SHOULD MAKE FOR A VERY COMFORTABLE
LATE JULY DAY.
TONIGHT (7PM-7AM): AGAIN...SEE OPENING PARAGRAPH FOR FURTHER
INSIGHT INTO THE DECISION TO ADD SPRINKLE POSSIBILITY INTO PARTS
OF KS ZONES. ALTHOUGH MODEL DISCREPANCY CONTINUES REGARDING
NORTHERN KS PRECIP POTENTIAL...ITS WORTH NOTING THAT THE VERY
LATEST 06Z NAM HAS BACKED OFF THE NORTHWARD EXTENT OF
SHOWER/THUNDERSTORM POTENTIAL...NOW KEEPING OVERNIGHT CONVECTION
JUST SOUTH OF THE CWA (MUCH THE SAME PLACEMENT AS THE ONGOING
ACTIVITY). IN THE MID-UPPER LEVELS TONIGHT...FLOW OVER THE CWA
STARTS TO TURN EVER-SO-SLIGHTLY NORTHWESTERLY...IN RESPONSE TO
THE SOUTHERN PLAINS RIDGE STARTING TO RETROGRADE WESTWARD A BIT.
WHILE FAIRLY SUBTLE LOW-MID LEVEL LIFT/CONVERGENCE IS EXPECTED TO
PROMOTE "SOME" COVERAGE OF SHOWERS/STORMS MAINLY JUST SOUTH OF THE
CWA...THE VAST MAJORITY OF THE LOCAL AREA SHOULD REMAIN VOID OF
EVEN SPRINKLES...WITH A LIKELY DECREASE IN MID-HIGH LEVEL CLOUDS
AS WELL FROM THE DAYTIME...THUS PROMOTING MOSTLY CLEAR SKIES
ESPECIALLY NORTH OF THE STATE LINE. AT THE SURFACE...LIGHT BREEZES
WILL CONTINUE IN THE PRESENCE OF BROAD HIGH PRESSURE...BUT LIKELY
TAKING ON MORE OF A SOUTHERLY AND/OR WESTERLY COMPONENT. ALL IN
ALL...LOW TEMPS ACROSS MOST OF THE CWA MAY END UP BEING VERY
SIMILAR TO THOSE OBSERVED THIS MORNING...BUT FOR NOW WILL AIM MOST
PLACES VERY SLIGHTLY WARMER...WITH MOST OF THE CWA BOTTOMING OUT
SOMEWHERE IN THE 58-63 RANGE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 400 AM CDT WED JUL 29 2015
AFTER A VERY NICE WEDNESDAY WE WILL WARM RIGHT BACK UP INTO THE
UPPER 80S TO LOWER 90S FOR THURSDAY THROUGH THE WEEKEND AND INTO
NEXT MONDAY...BEFORE PERHAPS ANOTHER COOL DOWN NEXT TUESDAY. WE DO
HAVE SEVERAL RAIN CHANCES...BUT CONFIDENCE IN SEEING PRECIPITATION
IS NOT THAT HIGH ON ANY GIVEN DAY. MOST LOCATIONS WILL LIKELY END UP
DRY THROUGH FRIDAY...BUT WE WILL SEE AT LEAST A FEW MORE CHANCES OF
RAIN THEREAFTER.
THURSDAY AND FRIDAY...THE HUMIDITY WILL BEGIN TO WORK BACK INTO THE
REGION. DEWPOINTS WILL RISE FROM THEIR LOW POINT IN THE LOWER 50S
TODAY...TO AROUND 60 ON THURSDAY...AND INTO THE MID 60S BY FRIDAY.
THE SFC WIND WILL BE FAIRLY LIGHT...BUT IS EXPECTED TO BECOME
GENERALLY SOUTHERLY...WHICH WILL HELP TO WARM THINGS UP A COUPLE
DEGREES BACK TO AROUND NORMAL IN THE UPPER 80S TO AROUND 90. THE
UPPER RIDGE OVER THE SOUTHERN PLAINS WILL RETROGRADE BACK TO THE
WEST AND SET UP OVER THE DESERT SOUTHWEST. IN OUR AREA THERE WILL BE
AN AREA OF WEAK SFC CONVERGENCE ACROSS OUR NORTHERN AND EASTERN
ZONES FRIDAY AFTERNOON THAT COULD POP A FEW ISOLATED THUNDERSTORMS
BASED ON THE 00Z NAM AND 00Z GFS. CONFIDENCE IS LOW AND CONVECTION
WOULD LIKELY BE VERY HIT AND MISS WITH MOST FOLKS LIKELY MISSING OUT
ON IT.
SATURDAY THROUGH MONDAY...NORTHWESTERLY FLOW ALOFT WILL SEND US A
FEW SHORTWAVES AND SUBSEQUENT THUNDERSTORM CHANCES. ONE SUCH
SHORTWAVE IS EVIDENT IN THE 00Z GFS AND 00Z ECMWF SATURDAY
AFTERNOON/EVENING. THEREFORE...WILL THROW SOME CHANCE POPS IN THE
FORECAST WITH THE HIGHEST POPS BEING ACROSS NORTHERN AND EASTERN
ZONES. OVERALL...AT LEAST THE WAY IT LOOK RIGHT NOW...PRECIPITATION
CHANCES WILL STILL BE FAIRLY LOW AT LESS THAN 50/50. WE SHOULD BE IN
BETWEEN SHORTWAVES ON SUNDAY SO CONFIDENCE IN DRY WEATHER IS FAIRLY
GOOD FOR SUNDAY. THE NEXT SHORTWAVE ENTERS THE PICTURE ON MONDAY BUT
FORECAST MODELS DIFFER ON THE SPEED OF THE ASSOCIATED FRONT. GIVEN
THE EXPECTATION OF HAVING SOME UPPER LEVEL SUPPORT IN THE GENERAL
AREA FROM THIS UPPER WAVE...WILL CALL FOR CHANCE POPS. TEMPERATURES
WILL REMAIN NEAR NORMAL DURING THIS STRETCH...OR GENERALLY IN THE
UPPER 80S TO LOWER 90S.
TUESDAY...CONFIDENCE IS PRETTY LOW THIS FAR OUT GIVEN THE
NORTHWESTERLY FLOW REGIME. THEREFORE...WILL STICK WITH THE
SUPERBLEND OF ALL MODELS...WHICH GIVES US A SMALL CHANCE OF
PRECIPITATION AND SLIGHTLY COOLER TEMPERATURES WITH HIGHS IN THE MID
TO UPPER 80S.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1236 AM CDT WED JUL 29 2015
COMPARED TO THE PAST 24 HOURS...SHOULD BE A CONSIDERABLY MORE
"STRAIGHTFORWARD" UPCOMING 24 HOURS IN THE AVIATION DEPARTMENT.
FIRST OFF...NOT ANTICIPATING ANY PRECIPITATION/THUNDERSTORMS.
CONFIDENCE IS ACTUALLY VERY HIGH IN VFR CEILING...ALTHOUGH MUCH
OF THE LATTER HALF OF THE PERIOD COULD FEATURE SOME CONSIDERABLE
MID-LEVEL CLOUD COVER. VISIBILITY-WISE...CONFIDENCE IS ALSO
RATHER HIGH IN VFR...BUT THERE DOES APPEAR TO BE THE SLIMMEST
POSSIBILITY FOR A BRIEF PERIOD OF MVFR EARLY THIS MORNING IN
LIGHT HAZE...SO AT LEAST HINTED AT THIS WITH A "6SM BR" MENTION.
AS FOR SURFACE WIND...THE VAST MAJORITY OF THE PERIOD SHOULD
FEATURE SPEEDS AT/BELOW 6KT...AND WITH A HIGH PRESSURE AXIS
CENTERED OVER THE REGION...DIRECTION WILL BE RATHER VARIABLE IN
NATURE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM...WESELY
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
948 AM PDT WED JUL 29 2015
.SYNOPSIS...MOISTURE WILL SPREAD NORTH INTO THE AREA TODAY INTO
TOMORROW ALLOWING FOR SHOWERS AND THUNDERSTORMS TO RETURN TO SOME
AREAS MAINLY DURING THE AFTERNOON AND EVENING HOURS. THE CHANCE OF
SHOWERS AND THUNDERSTORMS WILL LINGER FROM FRIDAY INTO NEXT MONDAY
THEN BEGIN TO DECREASE IN MOST AREAS ON TUESDAY AS DRIER AIR MOVES
BACK ON IN. TEMPERATURES WILL REMAIN NEAR NORMAL THROUGH THE WEEKEND
WARMING TO SLIGHTLY ABOVE NORMAL EARLY NEXT WEEK.
&&
.UPDATE...MOISTURE POOLED OVER THE LOWER COLORADO RIVER VALLEY
YESTERDAY HAS SPREAD AS FAR NORTH AS SOUTHERN NEVADA WITH SURFACE
DEWPOINTS INTO THE LOW TO MID 50S UP TO CAL-NEV-ARI AND LAUGHLIN.
RADAR IS DETECTING WEAK RETURNS IN PARTS OF SAN BERNARDINO, SRN
CLARK AND MOHAVE COUNTIES WITH LITTLE OF THAT REACHING THE GROUND.
MADE ONLY MINOR UPDATES TO THE FORECAST TODAY BASED ON 12Z HI-RES
AND HRRR OUTPUT. EXPANDED POPS SLIGHTLY FURTHER NORTHWARD IN THE
HIGHER TERRAIN OF FAR SOUTHERN CLARK COUNTY. LEFT STORMS OUT OF LAS
VEGAS BUT HRRR DOES SHOW THE POTENTIAL FOR OUTFLOW WINDS REACHING
THE VALLEY BETWEEN 00Z AND 01Z WHICH BEARS MONITORING.
&&
.AVIATION...FOR MCCARRAN...WINDS WILL FAVOR AN EASTERLY DIRECTION
AND BE LESS THAN 8 KTS THROUGH 03Z OR SO THURSDAY THEN TRANSITION TO
THE SOUTHWEST. FEW-SCT CLOUDS ABOVE 12K FT THIS AFTERNOON INTO
TONIGHT. THERE IS A SLIGHT CHANCE OF A SHRA OR TSRA AFTER 20Z TODAY
IN THE DAGGETT AND PEACH SPRINGS APPROACH CORRIDORS THROUGH AROUND
04Z OR SO THURSDAY. LEFT STORMS OUT OF LAS VEGAS BUT HRRR MODEL DOES
SHOW THE POTENTIAL FOR OUTFLOW WINDS REACHING THE VALLEY BETWEEN 00Z
AND 01Z WHICH BEARS MONITORING.
THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...TYPICAL DIURNAL WINDS ARE EXPECTED THROUGH TONIGHT AT
ALL TERMINALS. A SLIGHT CHANCE OF THUNDERSTORMS EXISTS MAINLY OVER
THE HIGHER TERRAIN IN AREAS SOUTH OF A KDAG-KIGM LINE WITH SCT-BKN
CLOUDS AVERAGING AOA 7-12K FEET. LOWER CIGS AND GUSTY WINDS POSSIBLE
NEAR STRONGER STORMS. MOSTLY CLEAR NORTH OF A KDAG-KIGM LINE. &&
.PREV DISCUSSION...256 AM PDT WED JUL 29 2015
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
AS IS EVIDENT ON SATELLITE AND LOOKING AT OBSERVATIONS THIS MORNING
MOISTURE IS MAKING A MOVE ON NORTH. IPW SENSORS SHOW A STEADY CLIMB
IN PWAT VALUES SINCE YESTERDAY WITH VALUES MAINLY BETWEEN 0.50 INCH
AND 1.00 INCH ACROSS MUCH OF THE AREA AND AS HIGH AS 1.48 INCH AT
VIDAL JUNCTION. SURFACE DEWPOINTS HAVE SHOWN A STEADY RISE IN THE
COLORADO RIVER VALLEY AS WELL IN THIS TIME FRAME. THERE WAS AN AREA
OF CLOUDS THAT POPPED UP LATE YESTERDAY EVENING IN LA PAZ AND
SOUTHERN MOHAVE COUNTIES WHICH HAS MOVED NORTH OVERNIGHT AND EVEN
TRIGGERED SOME RETURNS ON RADAR THIS MORNING. AS A RESULT, POPS WERE
TWEAKED UP A BIT TO ACCOUNT FOR THE POTENTIAL OF A FEW SPRINKLES OR
A VERY LIGHT SHOWER REACHING THE GROUND IN SOUTHERN MOHAVE AND
SOUTHEAST SAN BERNARDINO COUNTIES.
THE FLOW ALOFT REMAINS SOUTH TO SOUTHEAST INTO TONIGHT WHICH WILL
CONTINUE TO TRANSPORT MOISTURE ON UP. PWATS WILL CONTINUE TO RISE
THROUGH THE DAY AND BE OVER AN INCH ACROSS MOST OF THE SAN
BERNARDINO COUNTY DESERTS, SOUTHERN CLARK AND CENTRAL AND SOUTHERN
MOHAVE COUNTIES. WHILE WE WILL HAVE THE MOISTURE GOING FOR US TODAY
AS WELL AS SUFFICIENT INSTABILITY AND CAPE VALUES (LI`S OF 0 TO -2
COMPUTED AT THE SURFACE AND CAPE VALUES OF 300-600 J/KG), THERE IS
REALLY NO REAL MECHANISM OTHER THAN TERRAIN AND HEATING TO DRIVE
STORMS. THE MID AND HIGHER LEVEL CLOUD COVER STREAMING NORTH THIS
MORNING IS NOT TOO THICK AT THE PRESENT BUT COULD BE ENOUGH TO TRIM
BACK ON ACTIVITY IN MOHAVE COUNTY OR DELAY THE START OF IT. NORTH OF
THIS AREA, IT WILL BE TOO DRY AND TOO STABLE TODAY TO SEE MUCH
ACTIVITY THOUGH WE MAY SEE SOME CUMULUS DEVELOP THIS AFTERNOON
ESPECIALLY OVER THE SOUTHERN SIERRA. HIGH TEMPS WERE TWEAKED UP A
FEW DEGREES BASED ON YESTERDAY`S HIGHS AS WELL AS A BLEND OF THE
LATEST STATISTICAL GUIDANCE.
ACTIVITY SHOULD DECREASE THIS EVENING WITH THE LOSS OF HEATING.
THERE IS SOME POTENTIAL THURSDAY THAT SOME SORT OF MID-LEVEL
WEAKNESS AND ASSOCIATED PV MAX HEADS NORTHWEST, HOWEVER, THIS MAY
ALSO DEPEND ON WHAT GOES ON TO OUR SOUTHEAST THIS EVENING OVER THE
CENTRAL AND SOUTHERN PARTS OF ARIZONA. OTHERWISE MOISTURE WILL
LINGER AND SPREAD FURTHER NORTH ON THURSDAY AND BE SUFFICIENT FOR
SHOWERS AND STORMS IN ANY PART OF THE AREA BY FRIDAY. AGAIN, HEATING
AND TERRAIN WILL MAINLY DRIVE STORMS. TEMPS WILL REMAIN NEAR NORMAL
FOR HIGHS.
THE MAIN THREATS IN AND NEAR STORMS WILL BE GUSTY WINDS, HAIL,
BLOWING DUST AND FLASH FLOODING IN ANY STRONGER OR SLOWER MOVING
STORMS. THE FLASH FLOOD THREAT WILL INCREASE A BIT MORE THURSDAY
INTO FRIDAY AS THE MOISTURE CONTENT OF THE AIR INCREASES.
.LONG TERM...SATURDAY THROUGH TUESDAY.
IT IS LOOKING LIKE A LOW GRADE MONSOON PATTERN FOR THIS PERIOD. HIGH
PRESSURE CENTERED NEAR THE FOUR CORNERS REGION SATURDAY WILL KEEP A
SOUTHERLY FLOW OVER THE AREA AND ENOUGH MOISTURE AND INSTABILITY FOR
AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS AREA WIDE. THE MODELS DO
NOT REALLY SHOW MUCH OF A SHIFT IN THE HIGH CENTER WITH TIME BUT
THEY ARE HINTING AT THE FLOW MAYBE BECOMING MORE SOUTHWESTERLY WITH
SOME DRYING ACROSS THE WESTERN PART OF THE FORECAST AREA WITH TIME.
SINCE THE GFS AND ECMWF ARE BOTH SHOWING THIS TREND I WENT AHEAD AND
LOWERED POPS A TOUCH IN THE WEST SUNDAY AND MONDAY AND LOWERED POPS
A BIT MORE FOR TUESDAY. IF YOU BELIEVE THE MODELS THERE MAY NOT BE
ANY THUNDERSTORMS IN THE CWA BY TUESDAY BUT AS WE HAVE MENTIONED
BEFORE...THE MODELS FREQUENTLY GET TOO AGGRESSIVE FLUSHING MOISTURE
OUT THIS TIME OF YEAR. SO I KEPT A SLIGHT CHANCE OF THUNDERSTORMS IN
TUESDAY FOR MAINLY MOHAVE AND LINCOLN COUNTIES AND THE HIGHER
TERRAIN OF CLARK COUNTY. I KEPT TEMPERATURES CLOSE TO OR JUST
SLIGHTLY ABOVE NORMAL FOR THE LONG TERM WHICH IS CLOSE TO THE GFS
MEX GUIDANCE. I AM NOT READY TO BUY THE SIGNIFICANT WARMING
INDICATED BY THE ECE GUIDANCE WHICH HAS TEMPERATURES 5 PLUS DEGREES
ABOVE NORMAL SUNDAY THROUGH TUESDAY.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT
ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING
PROCEDURES WEDNESDAY THROUGH MONDAY.
&&
$$
UPDATE...PIERCE
SHORT TERM/AVIATION...STACHELSKI
LONG TERM...HARRISON
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
906 PM MDT THU JUL 30 2015
.UPDATE...
UPDATED POP/WEATHER GROUPINGS IN THE GRIDDED FORECAST FOR REST OF
TONIGHT. ALSO UPDATED THE FLASH FLOOD WATCH BY ELIMINATING
WESTERN/CENTRAL AREAS. LATEST RADAR/SATELLITE IMAGERY AND TO A
CERTAIN DEGREE MODELING SHOWS THE MAIN THREAT FOR HEAVY RAIN
ACROSS EASTERN AREAS. THUS LEFT THE WATCH UP THERE. MODELS SEEM TO
BE OVERDOING CONDITIONS ACROSS WESTERN/CENTRAL AREAS DESPITE SOME
FOCUSING WAVE FEATURES. THE LATEST HRRR HAS BACK OFF QPF NUMBERS
ACROSS SW/WC HIGHLANDS ALTHOUGH THERE IS A WAVE POISED TO IMPACT
THOSE AREAS TONIGHT. SUSPECT THE RAINFALL WILL BE MORE STRATIFORM
WITH LESS OF A HEAVY RAIN THREAT. SIMILARLY FOR NW AREAS WHERE
THERE IS SOME ONGOING RAINFALL WITHIN A MID LEVEL DEFORMATION
AREA. VERY MOIST ENVIRONMENT SO IT DOESNT TAKE MUCH TO PRODUCE A
RAIN SHOWER.
50
&&
.PREV DISCUSSION...555 PM MDT THU JUL 30 2015...
.AVIATION...
00Z TAF CYCLE
THOUGH A LATER START...SHRA/TSRA ARE DEVELOPING NOW ACROSS MUCH OF
NM. STORM MOTIONS WILL GENERALLY BE TOWARD THE N OR NW ACROSS
WESTERN NM...WITH MORE N TO NE MOTION ELSEWHERE. OUTFLOW BOUNDARY
COLLISIONS WILL HELP DRIVE NEW DEVELOPMENT. MVFR CIGS/VSBYS WILL
BE POSSIBLE WITH THE STRONGER STORMS IN HEAVY RAIN. SHOULD STORMS
DIMINISH LATE TONIGHT...COULD SEE MVFR/IFR CIGS ACROSS PORTIONS OF
THE EASTERN PLAINS...HOWEVER...SOME MODEL GUIDANCE IS SUGGESTING
THAT A WEAK DISTURBANCE ROUNDING THE UPPER HIGH OVER NE NM WILL
KEEP CONVECTION GOING OR REDEVELOPING DURING THE OVERNIGHT HOURS.
34
&&
.PREV DISCUSSION...240 PM MDT THU JUL 30 2015...
.SYNOPSIS...
SHOWERS AND STORMS WITH LOCALLY HEAVY RAINFALL WILL CONTINUE TO
IMPACT NEW MEXICO THROUGH THE WEEKEND. THE FLASH FLOOD POTENTIAL
WILL REMAIN ELEVATED AS SLOW-MOVING STORMS DROP A QUICK 1 TO 2
INCHES OF RAIN. AREAS OF STEEP TERRAIN...BURNED FORESTS...URBAN
DRAINAGES...AND AREAS THAT PICK UP DAILY ROUNDS OF HEAVY RAIN WILL
BE THE MOST SUSCEPTIBLE. A VERY SLOW DRYING AND WARMING TREND IS
EXPECTED BEGINNING NEXT WEEK.
&&
.DISCUSSION...
THE CLIMATOLOGICAL PEAK FOR DEEP ATMOSPHERIC MOISTURE AND FLASH
FLOOD POTENTIAL IS CERTAINLY DELIVERING AS WE NEAR THE END OF JULY
2015. A REMNANT CONVECTIVE VORTEX FROM LAST NIGHT MOVING SLOWLY
NORTH ALONG THE CONT DVD IS FOCUSING REDEVELOPMENT TODAY. ANOTHER
AREA OF MOISTURE CONVERGENCE IS FIRING UP FROM LINCOLN COUNTY NORTH
INTO TORRANCE COUNTY WHERE RADAR-BASED STORM TOTAL ACCUMULATION IS
ALREADY NEAR 3 INCHES IN SOME LOCALES. THE WEAKEST STEERING FLOW
IS FOCUSED OVER NORTHERN NM WHERE DEFORMATION STRETCHES FROM WEST
TO EAST OVER THE HIGH TERRAIN. ANY ACTIVITY THERE WILL BE NEARLY
STATIONARY AND PRODUCE TORRENTIAL RAINFALL. ALL THESE AREAS ARE
UNDER THE FLASH FLOOD WATCH AND NO CHANGES WILL BE MADE. SOME
MINOR RIVER FLOODING IS ALSO POSSIBLE ALONG TRIBUTARIES TO MAIN
STEM RIVERS SUCH AS THE RIO GRANDE AND PECOS THROUGH THE WEEKEND.
EXPECT LITTLE TO NO CHANGE FRIDAY...EXCEPT PERHAPS A GREATER FOCUS
FOR HEAVY RAINFALL FARTHER NORTHWEST TOWARD THE FOUR CORNERS. THIS
WEEKEND WILL SEE ELEVATED FLASH FLOOD POTENTIAL AS THE UPPER HIGH
ESTABLISHES FIRMLY OVERHEAD. EACH AFTERNOON OF HEAVY RAINFALL IN
THE SAME AREAS WILL EXACERBATE FLASH FLOOD POTENTIAL.
A SLOW WARMING AND DRYING TREND IS STILL EXPECTED AS WE HEAD INTO
EARLY NEXT WEEK WITH NO ADDITIONAL INFLUX OF MOISTURE NOTED. THE
RECYCLING PROCESS WILL BE THE DOMINANT PLAYER...WHICH WILL BE VERY
EFFICIENT. NASA SPORT LIS SHOWS MOIST SOILS ARE EXPANDING OVER A
LARGER AREA OF NM AND TO DEEPER LAYERS. OVERALL...CONDITIONS ARE
LOOKING VERY TYPICAL OF A MATURE MONSOON PATTERN THROUGH EARLY
AUGUST.
GUYER
&&
.FIRE WEATHER...
UPPER HIGH CENTER ATTEMPTING TO BECOME ESTABLISHED OVER NEW MEXICO
THIS AFTERNOON...AND MODELS PERSIST ON IT LINGERING OVER THE STATE
FOR MUCH OF THE UPCOMING WEEK...ALTHOUGH IT/S LIKELY TO WOBBLE
AROUND A BIT. MOISTURE TO REMAIN TRAPPED UNDER THE RIDGE...BUT
SHOULD VERY SLOWLY WARM AND DRY NEXT WEEK. CELL MOTION COULD BE
SOMEWHAT ERRATIC FOR THE REST OF THIS AFTERNOON AND TONIGHT...BUT
GENERALLY NORTHWEST AND NORTH WEST OF THE RGV AND NORTH TO NORTHEAST
EAST OF THE RGV. MOVEMENT AND SPEED WILL TREND TO SLOWER AND MORE
ERRATIC FRIDAY AND INTO THE WEEKEND WITH THE HIGH CENTER OVERHEAD.
THEREFORE...LOCALLY HEAVY RAINFALL WILL BE POSSIBLE AT LEAST THROUGH
FRIDAY.
HIGH TEMPERATURES TO VARY FROM MOSTLY BELOW AVERAGE THROUGH SUNDAY
TO NEAR TO ABOVE AVERAGE NEXT MONDAY THROUGH THURSDAY. WHILE MIN RH
VALUES WILL TREND DOWNWARD NEXT WEEK...OVERNIGHT RECOVERIES FORECAST
TO REMAIN EXCELLENT.
VENT RATES OVER PORTIONS OF THE NORTH WILL BE FAIR TO POOR THROUGH
SUNDAY. POOR RATES ARE FORECAST FOR THE NORTHEAST AND SOUTHWEST
MONDAY.
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 4 AM MDT FRIDAY FOR THE FOLLOWING ZONES...
NMZ512>515-523-527>537.
&&
$$
50
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
126 PM EDT WED JUL 29 2015
.SYNOPSIS...
HOT TEMPERATURES ARE EXPECTED ONCE AGAIN ACROSS THE NORTH COUNTRY
WITH HIGHS IN THE UPPER 80S TO LOWER 90S. A FEW THUNDERSTORMS WILL
BE POSSIBLE OVER THE HIGHER TERRAIN THIS AFTERNOON...BUT A MUCH
BETTER CHANCE FOR THUNDERSTORMS WILL COME ON THURSDAY AS A COLD
FRONT MOVES ACROSS THE REGION. NUMEROUS THUNDERSTORMS ARE
EXPECTED TO DEVELOP OVER THE NORTHERN ADIRONDACKS OF NEW YORK BY
MIDDAY ON THURSDAY AND MOVE EAST THROUGH THE AFTERNOON. THESE
THUNDERSTORMS WILL ALSO HAVE THE POTENTIAL TO BE STRONG OR SEVERE
WITH STRONG AND GUSTY WINDS...HAIL...AND HEAVY DOWNPOURS. COOLER
AND DRIER WEATHER RETURNS ON FRIDAY AS THE COLD FRONT EXITS THE
AREA THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1155 AM EDT WEDNESDAY...GOING FORECAST IN GOOD SHAPE.
TEMPERATURES ARE ALREADY IN THE MID 80S WITH SEVERAL MORE HOURS OF
HEATING TO GO. LATEST RAP ANALYSIS ALSO SHOWING BETWEEN 500-1500
J/KG OF MLCAPE...BUT STILL CAPPED FOR THE TIME BEING. CU FIELD IS
STARTING TO FORM OVER THE HIGHER ELEVATIONS. AN ISOLATED
SHOWER/STORM REMAINS POSSIBLE THIS AFTERNOON.
PREVIOUS DISCUSSION FROM 958 AM WEDNESDAY...
RIDGING ALOFT AND AT THE SURFACE WILL PROVIDE FOR ANOTHER MOSTLY
SUNNY AND HOT DAY. DO HAVE SOME THIN CIRRUS SPILLING OVER THE TOP
OF THE RIDGE BUT NOT ENOUGH TO OBSCURE THE SUN. WILL ALSO HAVE A
CU-FIELD DEVELOP THIS AFTERNOON...MAINLY OVER THE TERRAIN. LOW
LEVEL THERMAL FIELDS ARE ABOUT 2C WARMER THAN YESTERDAY...WHICH
SHOULD RESULT IN TEMPERATURES ABOUT 3 DEGREES WARMER THAN
YESTERDAY. THIS WILL YIELD HIGHS IN THE UPPER 80S AND LOWER 90S
AREA-WIDE. THE HEAT COMBINED WITH DEW POINTS IN THE MID/UPPER 60S
WILL PRODUCE HEAT INDEX VALUES OF 91 TO 97 DEGREES. THE
HEAT/HUMIDITY WILL ALSO LEAD TO THE DEVELOPMENT OF BETWEEN
500-1500 J/KG OF MLCAPE. MOST OF THE REGION SHOULD REMAIN
CAPPED...BUT THE HIGHER TERRAIN MAY PRODUCE JUST ENOUGH LIFT TO
TRIGGER AN ISOLATED SHOWER OR THUNDERSTORM OR TWO. WITH ONLY
LIMITED WIND SHEAR (20-25 KNOTS 0-6KM)...A SEVERE THREAT IS NOT
ANTICIPATED.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH FRIDAY/...
AS OF 414 AM EDT WEDNESDAY...WE ARE STILL LOOKING AT THE THREAT
FOR STRONG TO SEVERE THUNDERSTORMS ON THURSDAY ACROSS MUCH OF THE
AREA. A SHARP COLD FRONT WILL MOVE INTO THE SAINT LAWRENCE VALLEY
BY MIDDAY. THE MOISTURE GRADIENT ASSOCIATED WITH THE FRONT IS
RATHER SHARP...SO THIS BOUNDARY WILL BE A GOOD SOURCE OF LIFT AS
IT MOVES EASTWARD THURSDAY AFTERNOON. THE ATMOSPHERE WILL
DESTABILIZE IN ADVANCE OF THE FRONT WITH WITH HIGHS IN THE MID
80S TO LOWER 90S AND DEW POINTS WILL INTO THE 60S. STILL EXPECTING
THIS TO RESULT IN CAPE VALUES IN THE 1000-1500 J/KG RANGE. WHAT
CONTINUES TO STAND OUT IS THE INCREASING DEEP LAYER SHEAR OVER THE
TOP OF THE COLD FRONT AND INSTABILITY AXIS TO SUPPORT THE
DEVELOPMENT OF ORGANIZED STORMS WHICH BASED ON THE STRENGTH OF THE
INSTABILITY AND SHEAR...SHOULD BECOME STRONG TO SEVERE. AT THIS
TIME...THINKING STORMS FORM OVER THE NORTHERN ADIRONDACKS AND
QUICKLY INTENSIFY WITH THE CHAMPLAIN VALLEY AND REMAINDER OF
VERMONT HAVING THE BEST CHANCE TO EXPERIENCE THE STRONG TO SEVERE
STORMS. WILL INCLUDE THE MENTION OF GUSTY WINDS...HAIL...AND HEAVY
DOWNPOURS IN THE FORECAST. NARROW BAND OF STORMS EXITS THE AREA BY
EARLY EVENING AND WITH COLD FRONT ALSO EXITING THE AREA...COOLER
AND DRIER WEATHER SHOULD MOVE IN FOR THURSDAY NIGHT AND FRIDAY
WITH HIGHS ON FRIDAY CLOSER TO SEASONAL NORMALS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 310 AM EDT WEDNESDAY...LITTLE OVERALL CHANGE FROM PREVIOUS
FORECASTER THINKING IN REGARDS TO THE UPCOMING PATTERN FOR THE
EXTENDED PERIOD WITH MEDIUM RANGE GLOBAL MODELS REMAINING IN GOOD
AGREEMENT DEPICTING A LARGE-SCALE POLAR UPPER LOW TAKING RESIDENCE
OVER HUDSONS BAY. THIS LEAVES THE NORTHEAST IN A PERSISTENT BROAD
UPPER TROUGH WITH SEVERAL PIECES OF WEAK SHORTWAVE ENERGY MOVING
THROUGH THE FLOW ALOFT. FIRST PIECE MOVES THROUGH ON SATURDAY AND
THIS ENERGY COMBINED WITH DAYTIME HEATING MAY TRIGGER A FEW
SHOWERS AND/OR THUNDERSTORMS, THOUGH WITH THE LACK OF ANY STRONG
FORCING AND LIMITED DEEP LAYER MOISTURE RAINFALL SHOULD BE SHOWERY
IN NATURE AND ON THE LIGHT SIDE. BEST CHANCES FOR SHOWERS/STORMS
DURING THE PERIOD STILL LOOK TO BE MONDAY AND ESPECIALLY TUESDAY
AS A COUPLE STRONGER SHORTWAVES SHIFT THROUGH THE REGION AS THE
UPPER LOW DIGS SLIGHTLY SOUTHWARD FROM JAMES BAY INTO THE GREAT
LAKES. THIS WILL ALLOW A WEAK COLD FRONT TO MOVE ACROSS THE AREA
AS A BETTER FOCUS FOR PRECIPITATION. TEMPERATURES THROUGH THE
PERIOD WILL BE NEAR NORMAL WITH HIGHS IN THE MID 70S TO LOWER 80S,
AND LOWS IN THE MID 50S TO LOWER 60S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD WITH SCT-BKN MID/HIGH CLOUDS DRIFTING THROUGH THE REGION.
SOUTHWEST (EXCEPT SOUTHEAST AT KPBG/KRUT) AT 5 TO 10 KNOTS
THROUGH THE DAY, GOING CALM AGAIN AFTER 00Z. WINDS JUST OFF THE
SURFACE PICK UP TONIGHT AHEAD OF AN APPROACHING COLD FRONT WHICH
SHOULD INHIBIT ANY FOG AT KSLK BUT STILL POSSIBLE AT KMPV.
SHOWERS/THUNDERSTORMS DEVELOPING ALG/AHD COLD FRONT IN NRN NY
BETWEEN 14-17Z AND AFT 17Z IN VT.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY...
18Z THU - 00Z FRI: VFR WITH BRIEF MVFR/IFR IN SHOWERS/STORMS.
ISOLATED SEVERE TURBULENCE/WINDS/HAIL POSSIBLE.
00Z FRI - 12Z SAT: MAINLY VFR. CHANCE MVFR/IFR FOG.
12Z SAT - 00Z MON: MAINLY VFR. CHANCE SHRA/TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...EVENSON/MUCCILLI
SHORT TERM...EVENSON
LONG TERM...LAHIFF
AVIATION...SLW
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1158 AM EDT WED JUL 29 2015
.SYNOPSIS...
HOT TEMPERATURES ARE EXPECTED ONCE AGAIN ACROSS THE NORTH COUNTRY
WITH HIGHS IN THE UPPER 80S TO LOWER 90S. A FEW THUNDERSTORMS WILL
BE POSSIBLE OVER THE HIGHER TERRAIN THIS AFTERNOON...BUT A MUCH
BETTER CHANCE FOR THUNDERSTORMS WILL COME ON THURSDAY AS A COLD
FRONT MOVES ACROSS THE REGION. NUMEROUS THUNDERSTORMS ARE
EXPECTED TO DEVELOP OVER THE NORTHERN ADIRONDACKS OF NEW YORK BY
MIDDAY ON THURSDAY AND MOVE EAST THROUGH THE AFTERNOON. THESE
THUNDERSTORMS WILL ALSO HAVE THE POTENTIAL TO BE STRONG OR SEVERE
WITH STRONG AND GUSTY WINDS...HAIL...AND HEAVY DOWNPOURS. COOLER
AND DRIER WEATHER RETURNS ON FRIDAY AS THE COLD FRONT EXITS THE
AREA THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 1155 AM EDT WEDNESDAY...GOING FORECAST IN GOOD SHAPE.
TEMPERATURES ARE ALREADY IN THE MID 80S WITH SEVERAL MORE HOURS OF
HEATING TO GO. LATEST RAP ANALYSIS ALSO SHOWING BETWEEN 500-1500
J/KG OF MLCAPE...BUT STILL CAPPED FOR THE TIME BEING. CU FIELD IS
STARTING TO FORM OVER THE HIGHER ELEVATIONS. AN ISOLATED
SHOWER/STORM REMAINS POSSIBLE THIS AFTERNOON.
PREVIOUS DISCUSSION FROM 958 AM WEDNESDAY...
RIDGING ALOFT AND AT THE SURFACE WILL PROVIDE FOR ANOTHER MOSTLY
SUNNY AND HOT DAY. DO HAVE SOME THIN CIRRUS SPILLING OVER THE TOP
OF THE RIDGE BUT NOT ENOUGH TO OBSCURE THE SUN. WILL ALSO HAVE A
CU-FIELD DEVELOP THIS AFTERNOON...MAINLY OVER THE TERRAIN. LOW
LEVEL THERMAL FIELDS ARE ABOUT 2C WARMER THAN YESTERDAY...WHICH
SHOULD RESULT IN TEMPERATURES ABOUT 3 DEGREES WARMER THAN
YESTERDAY. THIS WILL YIELD HIGHS IN THE UPPER 80S AND LOWER 90S
AREA-WIDE. THE HEAT COMBINED WITH DEW POINTS IN THE MID/UPPER 60S
WILL PRODUCE HEAT INDEX VALUES OF 91 TO 97 DEGREES. THE
HEAT/HUMIDITY WILL ALSO LEAD TO THE DEVELOPMENT OF BETWEEN
500-1500 J/KG OF MLCAPE. MOST OF THE REGION SHOULD REMAIN
CAPPED...BUT THE HIGHER TERRAIN MAY PRODUCE JUST ENOUGH LIFT TO
TRIGGER AN ISOLATED SHOWER OR THUNDERSTORM OR TWO. WITH ONLY
LIMITED WIND SHEAR (20-25 KNOTS 0-6KM)...A SEVERE THREAT IS NOT
ANTICIPATED.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH FRIDAY/...
AS OF 414 AM EDT WEDNESDAY...WE ARE STILL LOOKING AT THE THREAT
FOR STRONG TO SEVERE THUNDERSTORMS ON THURSDAY ACROSS MUCH OF THE
AREA. A SHARP COLD FRONT WILL MOVE INTO THE SAINT LAWRENCE VALLEY
BY MIDDAY. THE MOISTURE GRADIENT ASSOCIATED WITH THE FRONT IS
RATHER SHARP...SO THIS BOUNDARY WILL BE A GOOD SOURCE OF LIFT AS
IT MOVES EASTWARD THURSDAY AFTERNOON. THE ATMOSPHERE WILL
DESTABILIZE IN ADVANCE OF THE FRONT WITH WITH HIGHS IN THE MID
80S TO LOWER 90S AND DEW POINTS WILL INTO THE 60S. STILL EXPECTING
THIS TO RESULT IN CAPE VALUES IN THE 1000-1500 J/KG RANGE. WHAT
CONTINUES TO STAND OUT IS THE INCREASING DEEP LAYER SHEAR OVER THE
TOP OF THE COLD FRONT AND INSTABILITY AXIS TO SUPPORT THE
DEVELOPMENT OF ORGANIZED STORMS WHICH BASED ON THE STRENGTH OF THE
INSTABILITY AND SHEAR...SHOULD BECOME STRONG TO SEVERE. AT THIS
TIME...THINKING STORMS FORM OVER THE NORTHERN ADIRONDACKS AND
QUICKLY INTENSIFY WITH THE CHAMPLAIN VALLEY AND REMAINDER OF
VERMONT HAVING THE BEST CHANCE TO EXPERIENCE THE STRONG TO SEVERE
STORMS. WILL INCLUDE THE MENTION OF GUSTY WINDS...HAIL...AND HEAVY
DOWNPOURS IN THE FORECAST. NARROW BAND OF STORMS EXITS THE AREA BY
EARLY EVENING AND WITH COLD FRONT ALSO EXITING THE AREA...COOLER
AND DRIER WEATHER SHOULD MOVE IN FOR THURSDAY NIGHT AND FRIDAY
WITH HIGHS ON FRIDAY CLOSER TO SEASONAL NORMALS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 310 AM EDT WEDNESDAY...LITTLE OVERALL CHANGE FROM PREVIOUS
FORECASTER THINKING IN REGARDS TO THE UPCOMING PATTERN FOR THE
EXTENDED PERIOD WITH MEDIUM RANGE GLOBAL MODELS REMAINING IN GOOD
AGREEMENT DEPICTING A LARGE-SCALE POLAR UPPER LOW TAKING RESIDENCE
OVER HUDSONS BAY. THIS LEAVES THE NORTHEAST IN A PERSISTENT BROAD
UPPER TROUGH WITH SEVERAL PIECES OF WEAK SHORTWAVE ENERGY MOVING
THROUGH THE FLOW ALOFT. FIRST PIECE MOVES THROUGH ON SATURDAY AND
THIS ENERGY COMBINED WITH DAYTIME HEATING MAY TRIGGER A FEW
SHOWERS AND/OR THUNDERSTORMS, THOUGH WITH THE LACK OF ANY STRONG
FORCING AND LIMITED DEEP LAYER MOISTURE RAINFALL SHOULD BE SHOWERY
IN NATURE AND ON THE LIGHT SIDE. BEST CHANCES FOR SHOWERS/STORMS
DURING THE PERIOD STILL LOOK TO BE MONDAY AND ESPECIALLY TUESDAY
AS A COUPLE STRONGER SHORTWAVES SHIFT THROUGH THE REGION AS THE
UPPER LOW DIGS SLIGHTLY SOUTHWARD FROM JAMES BAY INTO THE GREAT
LAKES. THIS WILL ALLOW A WEAK COLD FRONT TO MOVE ACROSS THE AREA
AS A BETTER FOCUS FOR PRECIPITATION. TEMPERATURES THROUGH THE
PERIOD WILL BE NEAR NORMAL WITH HIGHS IN THE MID 70S TO LOWER 80S,
AND LOWS IN THE MID 50S TO LOWER 60S.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 12Z THURSDAY...VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD WITH SCT-BKN MID/HIGH CLOUDS DRIFTING THROUGH THE REGION.
LIGHT WINDS EARLY THIS MORNING BECOME WEST-SOUTHWEST (EXCEPT
SOUTHEAST AT KPBG) AT 5 TO 10 KNOTS THROUGH THE DAY, GOING CALM
AGAIN AFTER 00Z. WINDS JUST OFF THE SURFACE PICK UP TONIGHT AHEAD
OF AN APPROACHING COLD FRONT WHICH SHOULD INHIBIT ANY FOG.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY...
12Z THU - 00Z FRI: VFR WITH BRIEF MVFR/IFR IN SHOWERS/STORMS.
ISOLATED SEVERE TURBULENCE/WINDS/HAIL POSSIBLE.
00Z FRI - 12Z SAT: MAINLY VFR. CHANCE MVFR/IFR FOG.
12Z SAT - 00Z MON: MAINLY VFR. CHANCE SHRA/TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...EVENSON/MUCCILLI
SHORT TERM...EVENSON
LONG TERM...LAHIFF
AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
807 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 730 PM THURSDAY...THE LATEST SFC PRESSURE PATTERN OVERLAYED
BY RADAR 0.5 DEGREE 88D REFLECTIVITY AND VIS SAT
IMAGERY...ILLUSTRATES THE LATEST POSITIONING OF THE SFC COLD
FRONT AS IT SLOWLY SNAKES TO THE EAST. SOME INTERACTION OF THE SEA
BREEZE AND CURRENT CONVECTION ILLUSTRATE THE RATHER "HO-HUM"
NATURE OF THE CONVECTION. PART OF THIS DUE TO SUBSIDENCE AND DRIER
AIR ALOFT OFTEN PREVENTING ANY FURTHER DEVELOPMENT. WITH THE
SOURCE OF SFC LIFT IE. DYNAMICS FROM THE COLD FRONT AND THE
DECAYING SEA BREEZE...HAVE OPTED TO CONTINUE A LOW CHANCE POP THRU
THE REMAINDER OF THE EVENING AND INTO THE PRE-DAWN FRI HOURS.
DIFFICULT TO FIND ANY MID OR UPPER LEVEL DYNAMICS THAT COULD
POSSIBLY INTENSIFY OR FURTHER SUSTAIN THE CONVECTION THRUOUT THE
EVENING AND OVERNIGHT HOURS. THE CAA TO LAG BEHIND THE COLD FRONT
BUT THE DRIER AIR SHOULD ATLEAST WORK INTO THE FAR NW PORTIONS OF
THE FA BY DAYBREAK FRI.
PREVIOUS........................................................
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 /00Z FRIDAY THROUGH TUESDAY/...
AS OF 00Z...RADAR SHOWING SOME SCATTERED CONVECTION ACROSS INLAND
ZONES THAT MIGHT BE IN THE VICINITY OF KLBT AND KFLO FOR THE NEXT
1-3 HOURS SO I WILL MAKE MENTION OF THIS IN TAF. SEA BREEZE FRONT
MAKING STEADY PROGRESS TO THE WEST AND HELPING TO DISSIPATE THESE
SHOWERS WHEN THEY INTERACT. FOR THE OVERNIGHT PERIOD EXPECT VFR
CONDITIONS ACROSS THE TERMINALS WITH BEST CHANCE OF ANY
PRECIPITATION OCCURRING AFTER SUNRISE WITH CONVECTION MAINLY OVER
THE EASTERN HALF OF THE CWA. POST FRONTAL LIGHT NORTHERLY FLOW IS
FORECAST. MODERATE CONFIDENCE THAT TERMINALS WILL STAY VFR ON
FRIDAY WITH JUST A CHANCE OF CONVECTION DIRECTLY OVER A TERMINAL
THROUGHOUT THE DAY.
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 745 PM THURSDAY...LOW PRESSURE OFFSHORE FROM CAPE
FEAR...WILL BEGIN TO GET SHUNTED TO THE N BY NE LATE THIS EVENING
AND OVERNIGHT. THIS IN RESPONSE TO THE APPROACHING COLD FRONT
FROM THE MAINLAND...THAT WILL SLOW ITS FORWARD PROGRESSION BY
DAYBREAK AND LIKELY STALL JUST PRIOR TO MOVING OFF THE CAROLINAS
MAINLAND. THIS DUE TO THE LACK OF ANY MID OR UPPER LEVEL PUSH.
WINDS CIRCULATING AROUND THE LOW AND PORTIONS OF THE FA WILL GIVE
WAY TO A SYNOPTIC SW-WSW FLOW WITH SPEEDS AROUND 10 KT.
SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...OCCASIONALLY UP TO 4 FT
ESPECIALLY OFF CAPE FEAR AND CAPE ROMAINE. DOMINANT PERIODS WILL
BE AROUND 7 TO 8 SECONDS...WITH A SSE PSEUDO GROUND SWELL THE
DOMINANT PLAYER.
PREVIOUS.......................................................
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 UNTIL 11 PM EDT THIS EVENING FOR
NCZ107.
MARINE...NONE.
&&
$$
SYNOPSIS...DRH
NEAR TERM...DCH/TRA
SHORT TERM...DRH
LONG TERM...JDW
AVIATION...MAC
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
908 AM EDT WED JUL 29 2015
.SYNOPSIS...A WEAK SURFACE TROUGH WILL REMAIN OVER CENTRAL NC TODAY
AS AN UPPER LEVEL RIDGE BRIEFLY BUILDS OVERHEAD. A COLD FRONT WILL
APPROACH FROM THE NORTHWEST ON THURSDAY AND SINK SOUTH OF THE AREA
THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 900 AM WEDNESDAY...
WITH REGARD TO THE REMAINDER OF THIS MORNING...THERE WILL BE LITTLE
CHANGE IN THE FORECAST OTHER THAN TO CONFINE SHOWER CHANCES TO THE
NE COASTAL PLAIN (I.E. WARREN/HALIFAX COUNTIES) THROUGH NOON. A NEW
DISCUSSION FOR THIS AFT/EVE INTO TONIGHT WILL BE POSTED EARLY THIS
AFTERNOON. -VINCENT
PRIOR DISCUSSION: NORTHWESTERLY FLOW ALOFT WILL SHIFT TO A LITTLE
MORE NORTHERLY TODAY AS THE CENTRAL US RIDGE BUILDS EAST IN RESPONSE
TO A STRONG SHORTWAVE CROSSING THE UPPER MIDWEST. WATER VAPOR
IMAGERY AND RAP H5 VORTICITY SUGGEST A COUPLE WEAK DISTURBANCES WILL
DROP SOUTH ACROSS THE AREA...BUT NEITHER APPEARS TO BE VERY STRONG
AND THERE SHOULDN`T BE MUCH IMPACT GIVEN THAT HEIGHTS BUILD ALOFT
AND INSTABILITY WILL BE WEAK. AT THE SURFACE...A TROUGH EXTENDING
SOUTH FROM THE MID ATLANTIC STATES APPEARS TO HAVE SUNK A LITTLE
FURTHER SOUTH IN RESPONSE TO THE LAST EVENINGS CONVECTION NEAR THE
NC-VA BORDER...NOW SITUATED FROM ROUGHLY DAVIDSON COUNTY NORTHEAST
TO GRANVILLE COUNTY. THIS COULD SERVE AS AN ADDITIONAL FOCUS FROM
SOME WIDELY SCATTERED CONVECTION...IN ADDITION TO CONVECTION OVER
THE HIGHER TERRAIN...AND RECENT RUNS OF THE HRRR HINT AT DEVELOPMENT
BY MIDDAY. IF NOTHING FORMS ON THIS BOUNDARY AND/OR IT WASHES
OUT...THEN CONVECTION WILL BE FOCUS OVER THE NORTHWEST PIEDMONT AND
SHOULDN`T HAVE MUCH OPPORTUNITY TO MOVE EAST GIVEN WEAK NORTHERLY
STEERING FLOW. OVERALL...THE COVERAGE OF SHOWERS/STORMS IS EXPECTED
TO BE LESS THAN THE PAST COUPLE OF DAYS. HIGHS SHOULD BE ABLE TO
REACH THE FULL SUN POTENTIAL AS IR IMAGERY SHOWS LITTLE IN THE WAY
OF UPSTREAM CLOUD COVER TO INHIBIT HEATING. HIGHS 88-93.
CONVECTION SHOULD SEND A LITTLE SOONER THIS EVENING WITH LOSS OF
HEATING AND NO SUPPORT FROM DISTURBANCES ALOFT. THERE IS A
DISTURBANCE OVER SOUTHERN MICHIGAN THIS MORNING THAT IS FORECAST TO
DIVE SOUTH LATE TONIGHT AND EARLY THURSDAY...WHICH COULD CONCEIVABLY
CAUSE SOME REDEVELOPMENT OF SHOWERS...MAINLY WEST..BY EARLY THURSDAY
MORNING...BUT GUIDANCE DOESN`T SHOW MUCH ACTIVITY...SO WILL LEAVE THE
OVERNIGHT FORECAST DRY. LOWS WILL BE IN THE LOWER 70S.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 400 AM WEDNESDAY...
A COLD FRONT...ATTENDANT TO AN OCCLUDED LOW WAY TO THE NORTH OVER
CENTRAL CANADA...WILL APPROACH FROM THE NORTHWEST ON THURSDAY. THE
PREFRONTAL LEE TROUGH WILL SHARPEN IN RESPONSE TO THE APPROACHING
FRONT... BUT WITH INSTABILITY STILL EXPECTED TO BE RELATIVELY
WEAK...MODELS ARE SURPRISINGLY DRY DURING THE DAY ON THURSDAY. THERE
IS A DISTURBANCE FORECAST TO DIVE SOUTH INTO THE AREA EARLY
THURSDAY...AS MENTIONED IN THE NEAR TERM DISCUSSION...AND EVOLUTION
OF THIS FEATURE MAY BE WORTH WATCHING TO SEE IF/HOW IT COULD IMPACT
CONVECTION INITIATION ON THURSDAY.
THE FRONT WILL PUSH INTO THE AREA THURSDAY EVENING...BUT POOR
DIURNAL TIMING AND FORCING LIMITED TO JUST FRONTAL CONVERGENCE
SHOULD RESULT IN JUST SCATTERED CONVECTION AND NO WIDESPREAD SEVERE
WEATHER.
HIGHS THURSDAY HAVE THE POTENTIAL TO REACH THE LOW TO MID 90S ACROSS THE
ENTIRE AREA AS THE 850MB THERMAL RIDGE SHIFTS OVER THE AREA AHEAD OF
THE FRONT AND 850MB TEMPS REACH 19-20C. SOME HIGH CLOUDS ASSOCIATED
WITH THE FRONTAL ZONE WILL SPREAD ACROSS THE AREA BUT CURRENTLY DO
NOT LOOK WIDESPREAD OR THICK ENOUGH TO IMPACT HIGHS. LOWS THURSDAY
NIGHT WILL BE MOSTLY IN THE LOW TO MID 70S...ESPECIALLY INT HE
SOUTHEAST WHERE THE FRONT WILL ONLY SLOW REACH BY FRIDAY MORNING.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 410 AM WEDNESDAY...
FORECAST RATIONALE REMAINS GENERALLY UNCHANGED FROM PREVIOUS DAYS.
THE MODELS REMAIN IN GOOD AGREEMENT REGARDING THE PERSISTENCE OF AN
EASTERN CONUS TROUGH FORECAST TO DEVELOP DURING THE NEAR AND SHORT
TERM...COINCIDENT WITH THE RETROGRESSION OF A SUB-TROPICAL RIDGE
FROM THE SOUTHERN PLAINS AND MID-MS VALLEY WEST TO THE FOUR CORNERS
REGION.
MEANWHILE IN THE LOW LEVELS...THE MODELS AGREE THAT A COLD FRONT
RELATED TO A POTENT UPPER LOW OVER SOUTHERN MANITOBA THIS MORNING
WILL BE INVOF THE I-95 CORRIDOR FRI MORNING...THEN DRIFT SOUTHEAST
THROUGH THE COASTAL PLAIN THROUGH THE MIDDAY-AFTERNOON HOURS. THIS
GRADUALLY DIFFUSING BOUNDARY WILL BE THE FOCUS FOR SHOWERS AND
STORMS CENTERED OVER THE EASTERN CAROLINAS FRI-SUN...WHILE A DRIER
AIR MASS BOTH AT THE SURFACE AND ALOFT SETTLES ACROSS THE WESTERN...
AND MUCH OF THE CENTRAL PART...OF NC. AS THE PREVIOUS SHIFT
NOTED...ANY NORTHWESTWARD SHIFT IN THE FRONTAL POSITION AND
ASSOCIATED AXIS OF TROPICAL MOISTURE --CHARACTERIZED BY PRECIPITABLE
WATER VALUES AOA TWO INCHES-- WOULD RESULT IN A WETTER WEEKEND FOR
PARTICULARLY EAST-CENTRAL NC.
THOUGH MODEL SPREAD INCREASES BY THE EARLY-MIDDLE OF NEXT WEEK...THE
MODELS TO VARYING DEGREES HAVE HINTED THAT THE TROPICAL MOISTURE
MAY GET DRAWN NORTH/INCORPORATED INTO THE LONGWAVE TROUGH BY LATE
SUN-MON...AT WHICH TIME THE PROBABILITY OF SHOWERS AND STORMS ARE
MORE LIKELY TO INCREASE THROUGHOUT CENTRAL NC.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 640 AM WEDNESDAY...
DENSE FOG THIS AT KINT THIS MORNING IS VERY ISOLATED AND WILL
IMPROVE QUICKLY...WITH VFR CONDITIONS LIKELY TO RETURN BY 13Z.
ELSEWHERE...SOME SCATTERED SHOWERS HAVE DEVELOPED NORTH OF KRDU/KRWI
AND ARE DRIFTING SLOWLY TO THE EAST-NORTHEAST...GENERALLY AWAY FROM
THE TERMINALS. SOME ADDITIONAL SHOWERS MAY DEVELOP IN THE NEXT
COUPLE HOURS...BUT THE IMPACTS OF THE SHOWERS SHOULD BE LIMITED AND
VFR CONDITIONS SHOULD PREVAIL.
AN UPPER LEVEL RIDGE WILL BRIEFLY BUILD OVER THE REGION TODAY AND
MAY LIMIT STORM COVERAGE MORE SO THAN IN PRIOR DAYS. AS SUCH...WILL
NOT MENTION THUNDER IN THE CURRENT TAF...BUT CHANCES WILL BE
GREATEST AT KGSO AND KINT ONCE AGAIN. STRATUS IS POSSIBLE AGAIN
TONIGHT...AND CONFIDENCE IS A LITTLE HIGHER THAN IN PAST NIGHTS
GIVEN A SLIGHTLY STRONGER WIND JUST ABOVE THE SURFACE AND A BETTER
AGREEMENT ON AMONG MODELS...WITH THE BEST CHANCE FROM KFAY TO KRWI.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NORTHWEST ON
THURSDAY...WITH SOME PREFRONTAL CONVECTION POSSIBLE THURSDAY
AFTERNOON. THE FRONT WILL THEN PUSH THROUGH THE AREA THURSDAY NIGHT
AND SETTLE SOUTH OF THE AREA ON FRIDAY. IF THIS FRONT DOES PUSH ALL
THE WAY THROUGH THE AREA...THEN VFR CONDITIONS WILL BE MUCH MORE
LIKELY FOR THE UPCOMING WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...22
LONG TERM...26
AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
640 AM EDT WED JUL 29 2015
.SYNOPSIS...A WEAK SURFACE TROUGH WILL REMAIN OVER CENTRAL NC TODAY
AS AN UPPER LEVEL RIDGE BRIEFLY BUILDS OVERHEAD. A COLD FRONT WILL
APPROACH FROM THE NORTHWEST ON THURSDAY AND SINK SOUTH OF THE AREA
THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 350 AM WEDNESDAY...
NORTHWESTERLY FLOW ALOFT WILL SHIFT TO A LITTLE MORE NORTHERLY TODAY
AS THE CENTRAL US RIDGE BUILDS EAST IN RESPONSE TO A STRONG
SHORTWAVE CROSSING THE UPPER MIDWEST. WATER VAPOR IMAGERY AND RAP H5
VORTICITY SUGGEST A COUPLE WEAK DISTURBANCES WILL DROP SOUTH ACROSS
THE AREA...BUT NEITHER APPEARS TO BE VERY STRONG AND THERE SHOULDN`T
BE MUCH IMPACT GIVEN THAT HEIGHTS BUILD ALOFT AND INSTABILITY WILL
BE WEAK. AT THE SURFACE...A TROUGH EXTENDING SOUTH FROM THE MID
ATLANTIC STATES APPEARS TO HAVE SUNK A LITTLE FURTHER SOUTH IN
RESPONSE TO THE LAST EVENINGS CONVECTION NEAR THE NC-VA BORDER...NOW
SITUATED FROM ROUGHLY DAVIDSON COUNTY NORTHEAST TO GRANVILLE COUNTY.
THIS COULD SERVE AS AN ADDITIONAL FOCUS FROM SOME WIDELY SCATTERED
CONVECTION...IN ADDITION TO CONVECTION OVER THE HIGHER TERRAIN...AND
RECENT RUNS OF THE HRRR HINT AT DEVELOPMENT BY MIDDAY. IF NOTHING
FORMS ON THIS BOUNDARY AND/OR IT WASHES OUT...THEN CONVECTION WILL
BE FOCUS OVER THE NORTHWEST PIEDMONT AND SHOULDN`T HAVE MUCH
OPPORTUNITY TO MOVE EAST GIVEN WEAK NORTHERLY STEERING FLOW.
OVERALL...THE COVERAGE OF SHOWERS/STORMS IS EXPECTED TO BE LESS THAN
THE PAST COUPLE OF DAYS. HIGHS SHOULD BE ABLE TO REACH THE FULL SUN
POTENTIAL AS IR IMAGERY SHOWS LITTLE IN THE WAY OF UPSTREAM CLOUD
COVER TO INHIBIT HEATING. HIGHS 88-93.
CONVECTION SHOULD SEND A LITTLE SOONER THIS EVENING WITH LOSS OF
HEATING AND NO SUPPORT FROM DISTURBANCES ALOFT. THERE IS A
DISTURBANCE OVER SOUTHERN MICHIGAN THIS MORNING THAT IS FORECAST TO
DIVE SOUTH LATE TONIGHT AND EARLY THURSDAY...WHICH COULD CONCEIVABLY
CAUSE SOME REDEVELOPMENT OF SHOWERS...MAINLY WEST..BY EARLY THURSDAY
MORNING...BUT GUIDANCE DOESN`T SHOW MUCH ACTIVITY...SO WILL LEAVE THE
OVERNIGHT FORECAST DRY. LOWS WILL BE IN THE LOWER 70S.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 400 AM WEDNESDAY...
A COLD FRONT...ATTENDANT TO AN OCCLUDED LOW WAY TO THE NORTH OVER
CENTRAL CANADA...WILL APPROACH FROM THE NORTHWEST ON THURSDAY. THE
PREFRONTAL LEE TROUGH WILL SHARPEN IN RESPONSE TO THE APPROACHING
FRONT... BUT WITH INSTABILITY STILL EXPECTED TO BE RELATIVELY
WEAK...MODELS ARE SURPRISINGLY DRY DURING THE DAY ON THURSDAY. THERE
IS A DISTURBANCE FORECAST TO DIVE SOUTH INTO THE AREA EARLY
THURSDAY...AS MENTIONED IN THE NEAR TERM DISCUSSION...AND EVOLUTION
OF THIS FEATURE MAY BE WORTH WATCHING TO SEE IF/HOW IT COULD IMPACT
CONVECTION INITIATION ON THURSDAY.
THE FRONT WILL PUSH INTO THE AREA THURSDAY EVENING...BUT POOR
DIURNAL TIMING AND FORCING LIMITED TO JUST FRONTAL CONVERGENCE
SHOULD RESULT IN JUST SCATTERED CONVECTION AND NO WIDESPREAD SEVERE
WEATHER.
HIGHS THURSDAY HAVE THE POTENTIAL TO REACH THE LOW TO MID 90S ACROSS THE
ENTIRE AREA AS THE 850MB THERMAL RIDGE SHIFTS OVER THE AREA AHEAD OF
THE FRONT AND 850MB TEMPS REACH 19-20C. SOME HIGH CLOUDS ASSOCIATED
WITH THE FRONTAL ZONE WILL SPREAD ACROSS THE AREA BUT CURRENTLY DO
NOT LOOK WIDESPREAD OR THICK ENOUGH TO IMPACT HIGHS. LOWS THURSDAY
NIGHT WILL BE MOSTLY IN THE LOW TO MID 70S...ESPECIALLY INT HE
SOUTHEAST WHERE THE FRONT WILL ONLY SLOW REACH BY FRIDAY MORNING.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 410 AM WEDNESDAY...
FORECAST RATIONALE REMAINS GENERALLY UNCHANGED FROM PREVIOUS DAYS.
THE MODELS REMAIN IN GOOD AGREEMENT REGARDING THE PERSISTENCE OF AN
EASTERN CONUS TROUGH FORECAST TO DEVELOP DURING THE NEAR AND SHORT
TERM...COINCIDENT WITH THE RETROGRESSION OF A SUB-TROPICAL RIDGE
FROM THE SOUTHERN PLAINS AND MID-MS VALLEY WEST TO THE FOUR CORNERS
REGION.
MEANWHILE IN THE LOW LEVELS...THE MODELS AGREE THAT A COLD FRONT
RELATED TO A POTENT UPPER LOW OVER SOUTHERN MANITOBA THIS MORNING
WILL BE INVOF THE I-95 CORRIDOR FRI MORNING...THEN DRIFT SOUTHEAST
THROUGH THE COASTAL PLAIN THROUGH THE MIDDAY-AFTERNOON HOURS. THIS
GRADUALLY DIFFUSING BOUNDARY WILL BE THE FOCUS FOR SHOWERS AND
STORMS CENTERED OVER THE EASTERN CAROLINAS FRI-SUN...WHILE A DRIER
AIR MASS BOTH AT THE SURFACE AND ALOFT SETTLES ACROSS THE WESTERN...
AND MUCH OF THE CENTRAL PART...OF NC. AS THE PREVIOUS SHIFT
NOTED...ANY NORTHWESTWARD SHIFT IN THE FRONTAL POSITION AND
ASSOCIATED AXIS OF TROPICAL MOISTURE --CHARACTERIZED BY PRECIPITABLE
WATER VALUES AOA TWO INCHES-- WOULD RESULT IN A WETTER WEEKEND FOR
PARTICULARLY EAST-CENTRAL NC.
THOUGH MODEL SPREAD INCREASES BY THE EARLY-MIDDLE OF NEXT WEEK...THE
MODELS TO VARYING DEGREES HAVE HINTED THAT THE TROPICAL MOISTURE
MAY GET DRAWN NORTH/INCORPORATED INTO THE LONGWAVE TROUGH BY LATE
SUN-MON...AT WHICH TIME THE PROBABILITY OF SHOWERS AND STORMS ARE
MORE LIKELY TO INCREASE THROUGHOUT CENTRAL NC.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 640 AM WEDNESDAY...
DENSE FOG THIS AT KINT THIS MORNING IS VERY ISOLATED AND WILL
IMPROVE QUICKLY...WITH VFR CONDITIONS LIKELY TO RETURN BY 13Z.
ELSEWHERE...SOME SCATTERED SHOWERS HAVE DEVELOPED NORTH OF KRDU/KRWI
AND ARE DRIFTING SLOWLY TO THE EAST-NORTHEAST...GENERALLY AWAY FROM
THE TERMINALS. SOME ADDITIONAL SHOWERS MAY DEVELOP IN THE NEXT
COUPLE HOURS...BUT THE IMPACTS OF THE SHOWERS SHOULD BE LIMITED AND
VFR CONDITIONS SHOULD PREVAIL.
AN UPPER LEVEL RIDGE WILL BRIEFLY BUILD OVER THE REGION TODAY AND
MAY LIMIT STORM COVERAGE MORE SO THAN IN PRIOR DAYS. AS SUCH...WILL
NOT MENTION THUNDER IN THE CURRENT TAF...BUT CHANCES WILL BE
GREATEST AT KGSO AND KINT ONCE AGAIN. STRATUS IS POSSIBLE AGAIN
TONIGHT...AND CONFIDENCE IS A LITTLE HIGHER THAN IN PAST NIGHTS
GIVEN A SLIGHTLY STRONGER WIND JUST ABOVE THE SURFACE AND A BETTER
AGREEMENT ON AMONG MODELS...WITH THE BEST CHANCE FROM KFAY TO KRWI.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NORTHWEST ON
THURSDAY...WITH SOME PREFRONTAL CONVECTION POSSIBLE THURSDAY
AFTERNOON. THE FRONT WILL THEN PUSH THROUGH THE AREA THURSDAY NIGHT
AND SETTLE SOUTH OF THE AREA ON FRIDAY. IF THIS FRONT DOES PUSH ALL
THE WAY THROUGH THE AREA...THEN VFR CONDITIONS WILL BE MUCH MORE
LIKELY FOR THE UPCOMING WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...22
LONG TERM...26
AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
413 AM EDT WED JUL 29 2015
.SYNOPSIS...A WEAK SURFACE TROUGH WILL REMAIN OVER CENTRAL NC TODAY
AS AN UPPER LEVEL RIDGE BRIEFLY BUILDS OVERHEAD. A COLD FRONT WILL
APPROACH FROM THE NORTHWEST ON THURSDAY AND SINK SOUTH OF THE AREA
THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 350 AM WEDNESDAY...
NORTHWESTERLY FLOW ALOFT WILL SHIFT TO A LITTLE MORE NORTHERLY TODAY
AS THE CENTRAL US RIDGE BUILDS EAST IN RESPONSE TO A STRONG
SHORTWAVE CROSSING THE UPPER MIDWEST. WATER VAPOR IMAGERY AND RAP H5
VORTICITY SUGGEST A COUPLE WEAK DISTURBANCES WILL DROP SOUTH ACROSS
THE AREA...BUT NEITHER APPEARS TO BE VERY STRONG AND THERE SHOULDN`T
BE MUCH IMPACT GIVEN THAT HEIGHTS BUILD ALOFT AND INSTABILITY WILL
BE WEAK. AT THE SURFACE...A TROUGH EXTENDING SOUTH FROM THE MID
ATLANTIC STATES APPEARS TO HAVE SUNK A LITTLE FURTHER SOUTH IN
RESPONSE TO THE LAST EVENINGS CONVECTION NEAR THE NC-VA BORDER...NOW
SITUATED FROM ROUGHLY DAVIDSON COUNTY NORTHEAST TO GRANVILLE COUNTY.
THIS COULD SERVE AS AN ADDITIONAL FOCUS FROM SOME WIDELY SCATTERED
CONVECTION...IN ADDITION TO CONVECTION OVER THE HIGHER TERRAIN...AND
RECENT RUNS OF THE HRRR HINT AT DEVELOPMENT BY MIDDAY. IF NOTHING
FORMS ON THIS BOUNDARY AND/OR IT WASHES OUT...THEN CONVECTION WILL
BE FOCUS OVER THE NORTHWEST PIEDMONT AND SHOULDN`T HAVE MUCH
OPPORTUNITY TO MOVE EAST GIVEN WEAK NORTHERLY STEERING FLOW.
OVERALL...THE COVERAGE OF SHOWERS/STORMS IS EXPECTED TO BE LESS THAN
THE PAST COUPLE OF DAYS. HIGHS SHOULD BE ABLE TO REACH THE FULL SUN
POTENTIAL AS IR IMAGERY SHOWS LITTLE IN THE WAY OF UPSTREAM CLOUD
COVER TO INHIBIT HEATING. HIGHS 88-93.
CONVECTION SHOULD SEND A LITTLE SOONER THIS EVENING WITH LOSS OF
HEATING AND NO SUPPORT FROM DISTURBANCES ALOFT. THERE IS A
DISTURBANCE OVER SOUTHERN MICHIGAN THIS MORNING THAT IS FORECAST TO
DIVE SOUTH LATE TONIGHT AND EARLY THURSDAY...WHICH COULD CONCEIVABLY
CAUSE SOME REDEVELOPMENT OF SHOWERS...MAINLY WEST..BY EARLY THURSDAY
MORNING...BUT GUIDANCE DOESN`T SHOW MUCH ACTIVITY...SO WILL LEAVE THE
OVERNIGHT FORECAST DRY. LOWS WILL BE IN THE LOWER 70S.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 400 AM WEDNESDAY...
A COLD FRONT...ATTENDANT TO AN OCCLUDED LOW WAY TO THE NORTH OVER
CENTRAL CANADA...WILL APPROACH FROM THE NORTHWEST ON THURSDAY. THE
PREFRONTAL LEE TROUGH WILL SHARPEN IN RESPONSE TO THE APPROACHING
FRONT... BUT WITH INSTABILITY STILL EXPECTED TO BE RELATIVELY
WEAK...MODELS ARE SURPRISINGLY DRY DURING THE DAY ON THURSDAY. THERE
IS A DISTURBANCE FORECAST TO DIVE SOUTH INTO THE AREA EARLY
THURSDAY...AS MENTIONED IN THE NEAR TERM DISCUSSION...AND EVOLUTION
OF THIS FEATURE MAY BE WORTH WATCHING TO SEE IF/HOW IT COULD IMPACT
CONVECTION INITIATION ON THURSDAY.
THE FRONT WILL PUSH INTO THE AREA THURSDAY EVENING...BUT POOR
DIURNAL TIMING AND FORCING LIMITED TO JUST FRONTAL CONVERGENCE
SHOULD RESULT IN JUST SCATTERED CONVECTION AND NO WIDESPREAD SEVERE
WEATHER.
HIGHS THURSDAY HAVE THE POTENTIAL TO REACH THE LOW TO MID 90S ACROSS THE
ENTIRE AREA AS THE 850MB THERMAL RIDGE SHIFTS OVER THE AREA AHEAD OF
THE FRONT AND 850MB TEMPS REACH 19-20C. SOME HIGH CLOUDS ASSOCIATED
WITH THE FRONTAL ZONE WILL SPREAD ACROSS THE AREA BUT CURRENTLY DO
NOT LOOK WIDESPREAD OR THICK ENOUGH TO IMPACT HIGHS. LOWS THURSDAY
NIGHT WILL BE MOSTLY IN THE LOW TO MID 70S...ESPECIALLY INT HE
SOUTHEAST WHERE THE FRONT WILL ONLY SLOW REACH BY FRIDAY MORNING.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 410 AM WEDNESDAY...
FORECAST RATIONALE REMAINS GENERALLY UNCHANGED FROM PREVIOUS DAYS.
THE MODELS REMAIN IN GOOD AGREEMENT REGARDING THE PERSISTENCE OF AN
EASTERN CONUS TROUGH FORECAST TO DEVELOP DURING THE NEAR AND SHORT
TERM...COINCIDENT WITH THE RETROGRESSION OF A SUB-TROPICAL RIDGE
FROM THE SOUTHERN PLAINS AND MID-MS VALLEY WEST TO THE FOUR CORNERS
REGION.
MEANWHILE IN THE LOW LEVELS...THE MODELS AGREE THAT A COLD FRONT
RELATED TO A POTENT UPPER LOW OVER SOUTHERN MANITOBA THIS MORNING
WILL BE INVOF THE I-95 CORRIDOR FRI MORNING...THEN DRIFT SOUTHEAST
THROUGH THE COASTAL PLAIN THROUGH THE MIDDAY-AFTERNOON HOURS. THIS
GRADUALLY DIFFUSING BOUNDARY WILL BE THE FOCUS FOR SHOWERS AND
STORMS CENTERED OVER THE EASTERN CAROLINAS FRI-SUN...WHILE A DRIER
AIR MASS BOTH AT THE SURFACE AND ALOFT SETTLES ACROSS THE WESTERN...
AND MUCH OF THE CENTRAL PART...OF NC. AS THE PREVIOUS SHIFT
NOTED...ANY NORTHWESTWARD SHIFT IN THE FRONTAL POSITION AND
ASSOCIATED AXIS OF TROPICAL MOISTURE --CHARACTERIZED BY PRECIPITABLE
WATER VALUES AOA TWO INCHES-- WOULD RESULT IN A WETTER WEEKEND FOR
PARTICULARLY EAST-CENTRAL NC.
THOUGH MODEL SPREAD INCREASES BY THE EARLY-MIDDLE OF NEXT WEEK...THE
MODELS TO VARYING DEGREES HAVE HINTED THAT THE TROPICAL MOISTURE
MAY GET DRAWN NORTH/INCORPORATED INTO THE LONGWAVE TROUGH BY LATE
SUN-MON...AT WHICH TIME THE PROBABILITY OF SHOWERS AND STORMS ARE
MORE LIKELY TO INCREASE THROUGHOUT CENTRAL NC.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 145 AM WEDNESDAY...
CONVECTION FROM LAST EVENING DIMINISHED A FEW HOURS AGO...LEAVING
JUST CONVECTIVE DEBRIS CLOUDS AT OR ABOVE 6K FT DRIFTING SOUTHEAST
ACROSS THE AREA. THE CRUX OF THE CLOUD COVER APPEARS TO BE MOVING
SOUTH OF THE AREA AND SOME DRIER AIR ALOFT IS MOVING IN FROM
UPSTREAM...WHICH SHOULD ALLOW SOME AREAS OF SUB-VFR VSBY TO DEVELOP.
BASED ON EARLIER RAINFALL...KINT AND KGSO SHOULD RUN THE BEST
CHANCE OF IFR OR LIFR VSBYS...AND KGSO HAS ALREADY REPORTED A PERIOD
OF 1/2SM VSBY WITH PARTIAL CLEARING. CONFIDENCE IS ONLY MEDIUM AT
THE MOMENT...BUT THERE IS SOME SUPPORT FROM THE HRRR MODEL. EXPECT
MAINLY MVFR VSBYS AT OTHER SITES...THOUGH THE OFTEN FOG PRONE KRWI
MAY SEE LOWER VSBYS AS WELL.
AN UPPER LEVEL RIDGE WILL BRIEFLY BUILD OVER THE REGION TODAY AND
MAY LIMIT STORM COVERAGE MORE SO THAN IN PRIOR DAYS. AS SUCH...WILL
NOT MENTION THUNDER IN THE CURRENT TAF...BUT CHANCES WILL BE
GREATEST AT KGSO AND KINT ONCE AGAIN.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NORTHWEST ON
THURSDAY...WITH SOME PREFRONTAL CONVECTION POSSIBLE THURSDAY
AFTERNOON. THE FRONT WILL THEN PUSH THROUGH THE AREA THURSDAY NIGHT
AND SETTLE SOUTH OF THE AREA ON FRIDAY. IF THIS FRONT DOES PUSH ALL
THE WAY THROUGH THE AREA...THEN VFR CONDITIONS WILL BE MUCH MORE
LIKELY FOR THE UPCOMING WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...22
LONG TERM...26
AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
400 AM EDT WED JUL 29 2015
.SYNOPSIS...A WEAK SURFACE TROUGH WILL REMAIN OVER CENTRAL NC TODAY
AS AN UPPER LEVEL RIDGE BRIEFLY BUILDS OVERHEAD. A COLD FRONT WILL
APPROACH FROM THE NORTHWEST ON THURSDAY AND SINK SOUTH OF THE AREA
THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 350 AM WEDNESDAY...
NORTHWESTERLY FLOW ALOFT WILL SHIFT TO A LITTLE MORE NORTHERLY TODAY
AS THE CENTRAL US RIDGE BUILDS EAST IN RESPONSE TO A STRONG
SHORTWAVE CROSSING THE UPPER MIDWEST. WATER VAPOR IMAGERY AND RAP H5
VORTICITY SUGGEST A COUPLE WEAK DISTURBANCES WILL DROP SOUTH ACROSS
THE AREA...BUT NEITHER APPEARS TO BE VERY STRONG AND THERE SHOULDN`T
BE MUCH IMPACT GIVEN THAT HEIGHTS BUILD ALOFT AND INSTABILITY WILL
BE WEAK. AT THE SURFACE...A TROUGH EXTENDING SOUTH FROM THE MID
ATLANTIC STATES APPEARS TO HAVE SUNK A LITTLE FURTHER SOUTH IN
RESPONSE TO THE LAST EVENINGS CONVECTION NEAR THE NC-VA BORDER...NOW
SITUATED FROM ROUGHLY DAVIDSON COUNTY NORTHEAST TO GRANVILLE COUNTY.
THIS COULD SERVE AS AN ADDITIONAL FOCUS FROM SOME WIDELY SCATTERED
CONVECTION...IN ADDITION TO CONVECTION OVER THE HIGHER TERRAIN...AND
RECENT RUNS OF THE HRRR HINT AT DEVELOPMENT BY MIDDAY. IF NOTHING
FORMS ON THIS BOUNDARY AND/OR IT WASHES OUT...THEN CONVECTION WILL
BE FOCUS OVER THE NORTHWEST PIEDMONT AND SHOULDN`T HAVE MUCH
OPPORTUNITY TO MOVE EAST GIVEN WEAK NORTHERLY STEERING FLOW.
OVERALL...THE COVERAGE OF SHOWERS/STORMS IS EXPECTED TO BE LESS THAN
THE PAST COUPLE OF DAYS. HIGHS SHOULD BE ABLE TO REACH THE FULL SUN
POTENTIAL AS IR IMAGERY SHOWS LITTLE IN THE WAY OF UPSTREAM CLOUD
COVER TO INHIBIT HEATING. HIGHS 88-93.
CONVECTION SHOULD SEND A LITTLE SOONER THIS EVENING WITH LOSS OF
HEATING AND NO SUPPORT FROM DISTURBANCES ALOFT. THERE IS A
DISTURBANCE OVER SOUTHERN MICHIGAN THIS MORNING THAT IS FORECAST TO
DIVE SOUTH LATE TONIGHT AND EARLY THURSDAY...WHICH COULD CONCEIVABLY
CAUSE SOME REDEVELOPMENT OF SHOWERS...MAINLY WEST..BY EARLY THURSDAY
MORNING...BUT GUIDANCE DOESN`T SHOW MUCH ACTIVITY...SO WILL LEAVE THE
OVERNIGHT FORECAST DRY. LOWS WILL BE IN THE LOWER 70S.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 400 AM WEDNESDAY...
A COLD FRONT...ATTENDANT TO AN OCCLUDED LOW WAY TO THE NORTH OVER
CENTRAL CANADA...WILL APPROACH FROM THE NORTHWEST ON THURSDAY. THE
PREFRONTAL LEE TROUGH WILL SHARPEN IN RESPONSE TO THE APPROACHING
FRONT... BUT WITH INSTABILITY STILL EXPECTED TO BE RELATIVELY
WEAK...MODELS ARE SURPRISINGLY DRY DURING THE DAY ON THURSDAY. THERE
IS A DISTURBANCE FORECAST TO DIVE SOUTH INTO THE AREA EARLY
THURSDAY...AS MENTIONED IN THE NEAR TERM DISCUSSION...AND EVOLUTION
OF THIS FEATURE MAY BE WORTH WATCHING TO SEE IF/HOW IT COULD IMPACT
CONVECTION INITIATION ON THURSDAY.
THE FRONT WILL PUSH INTO THE AREA THURSDAY EVENING...BUT POOR
DIURNAL TIMING AND FORCING LIMITED TO JUST FRONTAL CONVERGENCE
SHOULD RESULT IN JUST SCATTERED CONVECTION AND NO WIDESPREAD SEVERE
WEATHER.
HIGHS THURSDAY HAVE THE POTENTIAL TO REACH THE LOW TO MID 90S ACROSS THE
ENTIRE AREA AS THE 850MB THERMAL RIDGE SHIFTS OVER THE AREA AHEAD OF
THE FRONT AND 850MB TEMPS REACH 19-20C. SOME HIGH CLOUDS ASSOCIATED
WITH THE FRONTAL ZONE WILL SPREAD ACROSS THE AREA BUT CURRENTLY DO
NOT LOOK WIDESPREAD OR THICK ENOUGH TO IMPACT HIGHS. LOWS THURSDAY
NIGHT WILL BE MOSTLY IN THE LOW TO MID 70S...ESPECIALLY INT HE
SOUTHEAST WHERE THE FRONT WILL ONLY SLOW REACH BY FRIDAY MORNING.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM TUESDAY...
THE MAIN FEATURE FOR OUR AREA DURING THE LONG TERM PERIOD WILL BE
THE DEEPENING LONG WAVE TROUGH OVER THE EAST. IT WILL BEGIN LATE
THURSDAY AS THE TROUGH BEGINS DEEPENING OVER THE OHIO VALLEY AND MID
ATLANTIC REGION...AND IN DOING SO WILL PUSH A COLD FRONT ACROSS OUR
AREA THURSDAY NIGHT. WILL HAVE TO BEGIN RAMPING POPS UP ACROSS OUR
WESTERN ZONES DURING THE AFTERNOON THURSDAY...BUT MOST OF DAYTIME
THURSDAY SHOULD REMAIN DRY. THE BEST CHANCE FOR RAIN WILL BE
THURSDAY NIGHT INTO FRIDAY MORNING...THEN RAIN CHANCES ENDING FROM W-
E DURING THE AFTERNOON FRIDAY. TEMPS DURING THIS TIME NEAR NORMAL.
FAIR WEATHER THEN APPEARS TO BE IN STORE FOR CENTRAL NC OVER THE
WEEKEND WITH HIGH PRESSURE BUILDING TO OUR NORTH AND MUCH DRIER AIR
OVER OUR REGION. THE PROGGED LOW LEVEL AIRMASS STILL APPEARS TO
SUPPORT HIGHS AS WARM AS THE LOW 90S...SO LITTLE IF ANY RELIEF
TEMPERATURE-WISE DESPITE HIGH PRESSURE BUILDING TO OUR NORTH.
POPS EXPECTED TO REBOUND CLOSER TO DAILY CLIMO VALUES AS WE HEAD
THROUGH EARLY NEXT WEEK AND PWAT SLOWLY RECOVERS. HOWEVER...
COVERAGE SHOULD BE ISOLATED AT BEST GIVEN THE BETTER SYNOP FEATURES
REMAINING BOTH TO OUR NORTH AND TO OUR SOUTH.
IT`S WORTH NOTING THAT GIVEN THE LINGERING BOUNDARY AND LOW PRESSURE
TO OUR SOUTH DURING THIS TIME...ANY SLIGHT NORTHWARD SHIFT IN THE
PATTERN COULD MEAN HIGHER RAIN CHANCES FOR US DURING THE WEEKEND AND
EARLY NEXT WEEK...ESP ACROSS OUR SOUTHERN ZONES. SO GIVEN OUR
PROXIMITY TO THESE FEATURES...OUR CONFIDENCE IN THIS PART OF THE
FORECAST ISN`T PARTICULARLY HIGH.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 145 AM WEDNESDAY...
CONVECTION FROM LAST EVENING DIMINISHED A FEW HOURS AGO...LEAVING
JUST CONVECTIVE DEBRIS CLOUDS AT OR ABOVE 6K FT DRIFTING SOUTHEAST
ACROSS THE AREA. THE CRUX OF THE CLOUD COVER APPEARS TO BE MOVING
SOUTH OF THE AREA AND SOME DRIER AIR ALOFT IS MOVING IN FROM
UPSTREAM...WHICH SHOULD ALLOW SOME AREAS OF SUB-VFR VSBY TO DEVELOP.
BASED ON EARLIER RAINFALL...KINT AND KGSO SHOULD RUN THE BEST
CHANCE OF IFR OR LIFR VSBYS...AND KGSO HAS ALREADY REPORTED A PERIOD
OF 1/2SM VSBY WITH PARTIAL CLEARING. CONFIDENCE IS ONLY MEDIUM AT
THE MOMENT...BUT THERE IS SOME SUPPORT FROM THE HRRR MODEL. EXPECT
MAINLY MVFR VSBYS AT OTHER SITES...THOUGH THE OFTEN FOG PRONE KRWI
MAY SEE LOWER VSBYS AS WELL.
AN UPPER LEVEL RIDGE WILL BRIEFLY BUILD OVER THE REGION TODAY AND
MAY LIMIT STORM COVERAGE MORE SO THAN IN PRIOR DAYS. AS SUCH...WILL
NOT MENTION THUNDER IN THE CURRENT TAF...BUT CHANCES WILL BE
GREATEST AT KGSO AND KINT ONCE AGAIN.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NORTHWEST ON
THURSDAY...WITH SOME PREFRONTAL CONVECTION POSSIBLE THURSDAY
AFTERNOON. THE FRONT WILL THEN PUSH THROUGH THE AREA THURSDAY NIGHT
AND SETTLE SOUTH OF THE AREA ON FRIDAY. IF THIS FRONT DOES PUSH ALL
THE WAY THROUGH THE AREA...THEN VFR CONDITIONS WILL BE MUCH MORE
LIKELY FOR THE UPCOMING WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...22
LONG TERM...RAH
AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
145 AM EDT WED JUL 29 2015
.SYNOPSIS...A WEAK SURFACE TROUGH WILL REMAIN OVER CENTRAL NC TODAY
AS AN UPPER LEVEL RIDGE BRIEFLY BUILDS OVERHEAD. A COLD FRONT WILL
APPROACH FROM THE NORTHWEST ON THURSDAY AND SINK SOUTH OF THE AREA
THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1050 PM TUESDAY...
THE 00Z WEDNESDAY UPPER AIR ANALYSES CONTINUE TO SHOW THE UPPER
LEVEL RIDGE CENTERED TO THE WEST-SOUTHWEST...WITH GENERALLY NW FLOW
ALOFT OVER CENTRAL NC. ASIDE FROM A FEW LINGERING SHOWERS IN VA...
THE CONVECTION FROM EARLY THIS EVENING HAS ENDED. A FEW OF THE HI-
RES CAMS TRY TO GENERATE SOME ADDITIONAL SHOWER ACTIVITY IN THE NW
OVERNIGHT. ALTHOUGH CONFIDENCE IS NOT TERRIBLY HIGH AT THIS
TIME...WILL FORECAST A SLIGHT CHANCE FOR SHOWERS IN THE NW TONIGHT.
OTHERWISE...EXPECT LOWS IN THE LOW TO MID 70S OVERNIGHT.
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 335 PM TUESDAY...
UPPER RIDGE CENTERED OVER THE SOUTHERN PLAINS TEMPORARILY
AMPLIFIES/EXTENDS EASTWARD INTO THE CAROLINAS WEDNESDAY IN RESPONSE
TO A S/W TRAVERSING THE NORTHERN PLAINS. THIS BUILDING OF HEIGHTS
ALOFT WILL INDUCE A MID LEVEL CAP ON THE ATMOSPHERE...INHIBITING
CONVECTIVE DEVELOPMENT OVER MOST OF THE AREA. THE EXCEPTION WILL BE
THE FAR WEST AND NORTH SECTIONS OF THE CWA WHERE THE PERSISTENT
LEESIDE TROUGH AND A STALLED WEAK SFC BOUNDARY WILL PROVIDE A FOCUS
FOR IS ATTRIBUTED TO PATCHY FOG AND/OR LOW CLOUDS. THIS OCCURRENCE
APPEARS MORE LIKELY AT KRWI AND POSSIBLY KFAY.OLATED-SCATTERED
CONVECTION INT EH AFTERNOON-EARLY EVENING.
MAX TEMPS WEDNEDAY SHOULD BE COMPARABLE TO HIGH TEMPS RECORDED TODAY
(NEAR 90-LOWER 90S). POTENTIAL TO SEE A SPOT OR TWO IN THE SOUTHERN
PIEDMONT/SANDHILLS FLIRT WITH MID 90S. MIN TEMPS NEAR 70-LOWER 70S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM TUESDAY...
THE MAIN FEATURE FOR OUR AREA DURING THE LONG TERM PERIOD WILL BE
THE DEEPENING LONG WAVE TROUGH OVER THE EAST. IT WILL BEGIN LATE
THURSDAY AS THE TROUGH BEGINS DEEPENING OVER THE OHIO VALLEY AND MID
ATLANTIC REGION...AND IN DOING SO WILL PUSH A COLD FRONT ACROSS OUR
AREA THURSDAY NIGHT. WILL HAVE TO BEGIN RAMPING POPS UP ACROSS OUR
WESTERN ZONES DURING THE AFTERNOON THURSDAY...BUT MOST OF DAYTIME
THURSDAY SHOULD REMAIN DRY. THE BEST CHANCE FOR RAIN WILL BE
THURSDAY NIGHT INTO FRIDAY MORNING...THEN RAIN CHANCES ENDING FROM W-
E DURING THE AFTERNOON FRIDAY. TEMPS DURING THIS TIME NEAR NORMAL.
FAIR WEATHER THEN APPEARS TO BE IN STORE FOR CENTRAL NC OVER THE
WEEKEND WITH HIGH PRESSURE BUILDING TO OUR NORTH AND MUCH DRIER AIR
OVER OUR REGION. THE PROGGED LOW LEVEL AIRMASS STILL APPEARS TO
SUPPORT HIGHS AS WARM AS THE LOW 90S...SO LITTLE IF ANY RELIEF
TEMPERATURE-WISE DESPITE HIGH PRESSURE BUILDING TO OUR NORTH.
POPS EXPECTED TO REBOUND CLOSER TO DAILY CLIMO VALUES AS WE HEAD
THROUGH EARLY NEXT WEEK AND PWAT SLOWLY RECOVERS. HOWEVER...
COVERAGE SHOULD BE ISOLATED AT BEST GIVEN THE BETTER SYNOP FEATURES
REMAINING BOTH TO OUR NORTH AND TO OUR SOUTH.
IT`S WORTH NOTING THAT GIVEN THE LINGERING BOUNDARY AND LOW PRESSURE
TO OUR SOUTH DURING THIS TIME...ANY SLIGHT NORTHWARD SHIFT IN THE
PATTERN COULD MEAN HIGHER RAIN CHANCES FOR US DURING THE WEEKEND AND
EARLY NEXT WEEK...ESP ACROSS OUR SOUTHERN ZONES. SO GIVEN OUR
PROXIMITY TO THESE FEATURES...OUR CONFIDENCE IN THIS PART OF THE
FORECAST ISN`T PARTICULARLY HIGH.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 145 AM WEDNESDAY...
CONVECTION FROM LAST EVENING DIMINISHED A FEW HOURS AGO...LEAVING
JUST CONVECTIVE DEBRIS CLOUDS AT OR ABOVE 6K FT DRIFTING SOUTHEAST
ACROSS THE AREA. THE CRUX OF THE CLOUD COVER APPEARS TO BE MOVING
SOUTH OF THE AREA AND SOME DRIER AIR ALOFT IS MOVING IN FROM
UPSTREAM...WHICH SHOULD ALLOW SOME AREAS OF SUB-VFR VSBY TO DEVELOP.
BASED ON EARLIER RAINFALL...KINT AND KGSO SHOULD RUN THE BEST
CHANCE OF IFR OR LIFR VSBYS...AND KGSO HAS ALREADY REPORTED A PERIOD
OF 1/2SM VSBY WITH PARTIAL CLEARING. CONFIDENCE IS ONLY MEDIUM AT
THE MOMENT...BUT THERE IS SOME SUPPORT FROM THE HRRR MODEL. EXPECT
MAINLY MVFR VSBYS AT OTHER SITES...THOUGH THE OFTEN FOG PRONE KRWI
MAY SEE LOWER VSBYS AS WELL.
AN UPPER LEVEL RIDGE WILL BRIEFLY BUILD OVER THE REGION TODAY AND
MAY LIMIT STORM COVERAGE MORE SO THAN IN PRIOR DAYS. AS SUCH...WILL
NOT MENTION THUNDER IN THE CURRENT TAF...BUT CHANCES WILL BE
GREATEST AT KGSO AND KINT ONCE AGAIN.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE NORTHWEST ON
THURSDAY...WITH SOME PREFRONTAL CONVECTION POSSIBLE THURSDAY
AFTERNOON. THE FRONT WILL THEN PUSH THROUGH THE AREA THURSDAY NIGHT
AND SETTLE SOUTH OF THE AREA ON FRIDAY. IF THIS FRONT DOES PUSH ALL
THE WAY THROUGH THE AREA...THEN VFR CONDITIONS WILL BE MUCH MORE
LIKELY FOR THE UPCOMING WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...10
SHORT TERM...WSS
LONG TERM...RAH
AVIATION...22
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1131 AM EDT WED JUL 29 2015
.SYNOPSIS...
SUMMERTIME HEAT AND HUMIDITY WILL BE THE MAIN WEATHER STORY TODAY
ACROSS CENTRAL PENNSYLVANIA. A COLD FRONT WILL MOVE THROUGH THE
KEYSTONE STATE ON THURSDAY...WITH ISOLATED SEVERE THUNDERSTORMS
POSSIBLE NEAR THE LOWER SUSQUEHANNA VALLEY. FRIDAY WILL BE
SEASONABLY WARM AND DRY WITH MUCH LOWER HUMIDITY TO CLOSE OUT JULY
2015.
&&
.NEAR TERM /THROUGH TONIGHT/...
PATCHY FOG NEARLY COMPLETELY BURNED OFF THIS MORNING. FORECAST ON
TRACK WITH A HAZY HOT AND HUMID AFTERNOON ACROSS THE AREA. PRETTY
DECENT CHANCE THAT STATE COLLEGE WILL HAVE ITS FIRST 90 DEGREE DAY
IN 2 YEARS. HRRR SHOWS WIDELY SCATTERED CONVECTION FIRING OFF ON
SOUTHERN CWA RIDGES AND DRIFTING SLOWLY EASTWARD. MID LEVEL TEMPS
STILL WARM AND THIS WILL LIMIT WIDESPREAD CONVECTION.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
SHORT TERM MODEL DATA OVER THE LAST TWO CYCLES ARE A TAD FASTER
WITH THE EWD MVMT OF THE SFC COLD FRONT FCST TO SWEEP ACROSS SERN
CANADA AND THE NORTHEAST/MID ATLANTIC STATES ON D2/THURSDAY. WEAK
HEIGHT FALLS ARE STILL EXPECTED TO OVERSPREAD CENTRAL PA ON THE
SRN PERIPHERY OF STRONG UPPER TROUGH AMPLIFYING OVER ERN CANADA.
EARLY-DAY CLOUD COVER W/ISOLD SHOWERS ALONG EWD-ADVANCING COLD
FRONT SHOULD EXTEND FURTHER INTO THE INTERIOR CENTRAL ZONES.
WHILE THE BEST LARGE SCALE FORCING FOR ASCENT/0-6KM SHEAR AND
MID-LEVEL LAPSE RATES WILL BE DISPLACED FURTHER TO THE NORTH OVER
THE NEW ENGLAND STATES...STILL THINK THAT THE SERN 1/3 TO 1/4 OF
THE CWA STANDS AT BETTER THAN 50/50 ODDS TO SEE A SCT TSTMS AHEAD
OF THE COLD FRONT...A FEW OF WHICH MAY BE STRONG TO MARGINALLY
SEVERE WITH LOCALIZED WIND DAMAGE POTENTIAL GIVEN STEEP LOW-LEVEL
LAPSE RATES AND DCAPE VALUES IN EXCESS OF 1000 J/KG. PREVIOUS SPC
D3 MRGL RISK HAS BEEN SHIFTED SOUTH/EAST NOW COVERING ONLY PORTIONS
OF THE LWR SUSQ VLY. DRIER LOW PWAT AIR QUICKLY SPREADS INTO THE
AREA BEHIND THE FROPA AND ENDS THE PCPN RISK IN THE FAR SE
COUNTIES BY LATE THURSDAY EVE/00Z FRI.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
LITTLE CHANGE IS ANTICIPATED IN THE LARGE SCALE FLOW PATTERN
ACROSS THE EASTERN U.S. THROUGH THE MEDIUM RANGE PERIOD...WITH A
MEAN RIDGE IN THE WEST AND BROAD TROUGH EXTENDING SWD FROM HUDSON
BAY VORTEX AND EAST OF THE CONTINENTAL DIVIDE. CONVECTIVE PCPN
SHOULD BE RATHER SPARSE AND FOCUSED ALONG WEAKENING NRN STREAM
FRONTAL SYSTEMS PROGRESSING SEWD FROM THE GREAT LAKES ABOUT EVERY
1-2 DAYS STARTING ON SATURDAY. CONFIDENCE IN TIMING IS LOW
ESPECIALLY INTO EARLY NEXT WEEK GIVEN INCREASING MODEL SPREAD.
TEMPERATURES SHOULD COOL BACK TO SEASONAL AVERAGES INTO THE
BEGINNING OF AUGUST.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
FOG DISSIPATED AND VFR CONDITIONS THIS AFTERNOON UNDER HIGH
PRESSURE. CLOUDS WILL START TO ADVANCE TONIGHT AHEAD OF A COLD
FRONT APPROACHING FROM THE WEST. MVFR CIGS AND VSBYS ARE POSSIBLE
BEGINNING IN THE SOUTHWEST AND THEN SPREADING EASTWARD AS SHOWERS
IN ADVANCE OF THE FRONT MAY NUDGE INTO BFD BEFORE SUNRISE
THURSDAY.
THE FRONT SHOULD PASS THURSDAY BRINGING DRIER CONDITIONS AND A
DECREASE IN THE COVERAGE OF SHOWERS AND THUNDERSTORMS LATE
THURSDAY INTO FRIDAY.
OUTLOOK...
FRI...MAINLY VFR.
SAT...MAINLY VFR...PM TSRA POSS W.
SUN...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...ROSS
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...ROSS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1100 AM EDT WED JUL 29 2015
.SYNOPSIS...
SUMMERTIME HEAT AND HUMIDITY WILL BE THE MAIN WEATHER STORY TODAY
ACROSS CENTRAL PENNSYLVANIA. A COLD FRONT WILL MOVE THROUGH THE
KEYSTONE STATE ON THURSDAY...WITH ISOLATED SEVERE THUNDERSTORMS
POSSIBLE NEAR THE LOWER SUSQUEHANNA VALLEY. FRIDAY WILL BE
SEASONABLY WARM AND DRY WITH MUCH LOWER HUMIDITY TO CLOSE OUT JULY
2015.
&&
.NEAR TERM /THROUGH TONIGHT/...
PATCHY FOG NEARLY COMPLETELY BURNED OFF THIS MORNING. FORECAST ON
TRACK WITH A HAZY HOT AND HUMID AFTERNOON ACROSS THE AREA. PRETTY
DECENT CHANCE THAT STATE COLLEGE WILL HAVE ITS FIRST 90 DEGREE DAY
IN 2 YEARS. HRRR SHOWS WIDELY SCATTERED CONVECTION FIRING OFF ON
SOUTHERN CWA RIDGES AND DRIFTING SLOWLY EASTWARD. MID LEVEL TEMPS
STILL WARM AND THIS WILL LIMIT WIDESPREAD CONVECTION.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
SHORT TERM MODEL DATA OVER THE LAST TWO CYCLES ARE A TAD FASTER
WITH THE EWD MVMT OF THE SFC COLD FRONT FCST TO SWEEP ACROSS SERN
CANADA AND THE NORTHEAST/MID ATLANTIC STATES ON D2/THURSDAY. WEAK
HEIGHT FALLS ARE STILL EXPECTED TO OVERSPREAD CENTRAL PA ON THE
SRN PERIPHERY OF STRONG UPPER TROUGH AMPLIFYING OVER ERN CANADA.
EARLY-DAY CLOUD COVER W/ISOLD SHOWERS ALONG EWD-ADVANCING COLD
FRONT SHOULD EXTEND FURTHER INTO THE INTERIOR CENTRAL ZONES.
WHILE THE BEST LARGE SCALE FORCING FOR ASCENT/0-6KM SHEAR AND
MID-LEVEL LAPSE RATES WILL BE DISPLACED FURTHER TO THE NORTH OVER
THE NEW ENGLAND STATES...STILL THINK THAT THE SERN 1/3 TO 1/4 OF
THE CWA STANDS AT BETTER THAN 50/50 ODDS TO SEE A SCT TSTMS AHEAD
OF THE COLD FRONT...A FEW OF WHICH MAY BE STRONG TO MARGINALLY
SEVERE WITH LOCALIZED WIND DAMAGE POTENTIAL GIVEN STEEP LOW-LEVEL
LAPSE RATES AND DCAPE VALUES IN EXCESS OF 1000 J/KG. PREVIOUS SPC
D3 MRGL RISK HAS BEEN SHIFTED SOUTH/EAST NOW COVERING ONLY PORTIONS
OF THE LWR SUSQ VLY. DRIER LOW PWAT AIR QUICKLY SPREADS INTO THE
AREA BEHIND THE FROPA AND ENDS THE PCPN RISK IN THE FAR SE
COUNTIES BY LATE THURSDAY EVE/00Z FRI.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
LITTLE CHANGE IS ANTICIPATED IN THE LARGE SCALE FLOW PATTERN
ACROSS THE EASTERN U.S. THROUGH THE MEDIUM RANGE PERIOD...WITH A
MEAN RIDGE IN THE WEST AND BROAD TROUGH EXTENDING SWD FROM HUDSON
BAY VORTEX AND EAST OF THE CONTINENTAL DIVIDE. CONVECTIVE PCPN
SHOULD BE RATHER SPARSE AND FOCUSED ALONG WEAKENING NRN STREAM
FRONTAL SYSTEMS PROGRESSING SEWD FROM THE GREAT LAKES ABOUT EVERY
1-2 DAYS STARTING ON SATURDAY. CONFIDENCE IN TIMING IS LOW
ESPECIALLY INTO EARLY NEXT WEEK GIVEN INCREASING MODEL SPREAD.
TEMPERATURES SHOULD COOL BACK TO SEASONAL AVERAGES INTO THE
BEGINNING OF AUGUST.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
PATCHY FOG CONTINUES TO LINGER AT LNS AND UNV AND WILL SLOWLY
DISSIPATE BETWEEN 12Z AND 14Z. AFTER 14Z VFR CONDITIONS WILL
DOMINATE THE REST OF THE DAY UNDER HIGH PRESSURE. CLOUDS WILL
START TO ADVANCE TONIGHT AHEAD OF A COLD FRONT APPROACHING FROM
THE WEST. MVFR CIGS AND VSBYS ARE POSSIBLE BEGINNING IN THE
SOUTHWEST AND THEN SPREADING EASTWARD AS SHOWERS IN ADVANCE OF
THE FRONT MAY NUDGE INTO BFD BEFORE SUNRISE THURSDAY.
THE FRONT SHOULD PASS THURSDAY BRINGING DRIER CONDITIONS AND A
DECREASE IN THE COVERAGE OF SHOWERS AND THUNDERSTORMS LATE
THURSDAY INTO FRIDAY.
OUTLOOK...
FRI...MAINLY VFR.
SAT...MAINLY VFR...PM TSRA POSS W.
SUN...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...ROSS
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
210 AM EDT WED JUL 29 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 TODAY/...
AS OF 2 AM...I WILL RECONFIGURE THE FOG MENTION TO LATEST GUIDANCE
AND OBSERVATIONS. OTHERWISE...THE CURRENT FORECAST REMAINS ON TRACK.
AS OF 1215 AM...LATEST REGIONAL RADAR COMPOSITE INDICATES THAT
SHOWERS HAVE DISSIPATED ACROSS THE CWA. LATEST GUIDANCE SHOWS LITTLE
POTENTIAL FOR SHOWERS TO DEVELOP THROUGH THE REST OF THE NIGHT. I
WILL UPDATE THE FORECAST TO REDUCE POPS BELOW SCHC AND DELAY MENTION
OF FOG.
0200 UTC UPDATE...POPS HAVE BEEN REDUCED OVER MOST OF THE AREA PER
RADAR TRENDS...WITH THE EXCEPTION OF THE NW NC PIEDMONT WHERE
ACTIVITY IS MOST PRONOUNCED. ONLY MINOR CHANGES WERE MADE TO
TEMPERATURES AND DEW POINTS OVERNIGHT. SKY COVER WAS UPDATED FROM
INFRARED SATELLITE IMAGERY.
0000 UTC UPDATE...POPS HAVE BEEN ADJUSTED TO ACCOUNT FOR MORE
CONVECTION MOVING TOWARD THE NW NC PIEDMONT...AND ACTIVITY OVER THE
SC PIEDMONT. QPF WAS ADJUSTED ACCORDINGLY.
2315 UTC UPDATE...POPS HAVE BEEN INCREASED IN THE NW NC
PIEDMONT...THE SOUTHERN INTERSTATE 77 CORRIDOR...AND THE SW NC
MOUNTAINS PER RADAR TRENDS. QPF HAS BEEN ADJUSTED ACCORDINGLY. SKY
COVER WAS UPDATED FROM VISIBLE SATELLITE IMAGERY...WITH INCREASES IN
THE PIEDMONT AND MOUNTAINS...AND DECREASES IN BETWEEN.
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 /TONIGHT 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 /06Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...WET GROUND AND HUMID BL CONDITIONS ARE WIDESPREAD ACROSS
THE NC PIEDMONT THIS MORNING. BASED ON LATEST MOS GUIDANCE AND
FORECAST SOUNDING...IT APPEARS CONDITIONS WILL BECOME SUPPORTIVE FOR
MVFR FOG DURING THE PRE DAWN HOURS. THE TAF WILL INCLUDE A TEMPO FOR
8Z TO 12Z FOR 5SM BR. SIMILAR TO TUESDAY...EARLY MORNING HEATING
MAY SUPPORT MVFR CEILINGS THROUGH MID MORNING. A SWEEPING MID LEVEL
SHORTWAVE WILL APPROACH THE REGION THIS AFTERNOON...LIKELY
TRIGGERING CLUSTERS OF TSRA. USING THE EXAMPLE FROM TUESDAY...I WILL
INCLUDE A PROB30 FOR TSRA FROM 19Z THROUGH 23Z. WINDS SHOULD FAVOR A
SOUTH DIRECTION...LIKELY REMAINING LESS THAN 5 KTS.
ELSEWHERE...OVERALL CONDITIONS SHOULD FOLLOW THE TIMING OF CLT. KAVL
AND KHKY SHOULD SEE THE GREATEST POTENTIAL FOR FOG AND LOW CLOUDS
EARLY THIS MORNING. OTHERWISE...THE ENVIRONMENT SHOULD YIELD MORNING
MVFR STRATUS...MIXING TO VFR CU BY MID DAY. A SWEEPING MID LEVEL
SHORTWAVE WILL APPROACH THE REGION THIS AFTERNOON...LIKELY
TRIGGERING CLUSTERS OF TSRA. USING THE EXAMPLE FROM TUESDAY...I WILL
INCLUDE A PROB30 FOR TSRA FROM 19Z THROUGH 23Z.
OUTLOOK...AN UPPER LEVEL TROUGH WILL AMPLIFY ACROSS THE ATLANTIC
STATES LATE IN THE WEEK...WITH THE LIKELY PASSAGE OF A COLD FRONT ON
FRIDAY. THE POTENTIAL FOR CONVECTION WILL INCREASE THROUGH
FRIDAY...THEN DECREASE BEHIND THE FRONT ON SATURDAY.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 93% MED 67% HIGH 100% HIGH 100%
KGSP LOW 56% MED 65% HIGH 100% HIGH 100%
KAVL MED 75% MED 70% HIGH 100% HIGH 100%
KHKY MED 74% MED 76% HIGH 100% HIGH 100%
KGMU MED 74% MED 63% HIGH 100% HIGH 100%
KAND HIGH 81% MED 63% 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...NED
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...NED
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1219 AM EDT WED JUL 29 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 TODAY/...
AS OF 1215 AM...LATEST REGIONAL RADAR COMPOSITE INDICATES THAT
SHOWERS HAVE DISSIPATED ACROSS THE CWA. LATEST GUIDANCE SHOWS LITTLE
POTENTIAL FOR SHOWERS TO DEVELOP THROUGH THE REST OF THE NIGHT. I
WILL UPDATE THE FORECAST TO REDUCE POPS BELOW SCHC AND DELAY MENTION
OF FOG.
0200 UTC UPDATE...POPS HAVE BEEN REDUCED OVER MOST OF THE AREA PER
RADAR TRENDS...WITH THE EXCEPTION OF THE NW NC PIEDMONT WHERE
ACTIVITY IS MOST PRONOUNCED. ONLY MINOR CHANGES WERE MADE TO
TEMPERATURES AND DEW POINTS OVERNIGHT. SKY COVER WAS UPDATED FROM
INFRARED SATELLITE IMAGERY.
0000 UTC UPDATE...POPS HAVE BEEN ADJUSTED TO ACCOUNT FOR MORE
CONVECTION MOVING TOWARD THE NW NC PIEDMONT...AND ACTIVITY OVER THE
SC PIEDMONT. QPF WAS ADJUSTED ACCORDINGLY.
2315 UTC UPDATE...POPS HAVE BEEN INCREASED IN THE NW NC
PIEDMONT...THE SOUTHERN INTERSTATE 77 CORRIDOR...AND THE SW NC
MOUNTAINS PER RADAR TRENDS. QPF HAS BEEN ADJUSTED ACCORDINGLY. SKY
COVER WAS UPDATED FROM VISIBLE SATELLITE IMAGERY...WITH INCREASES IN
THE PIEDMONT AND MOUNTAINS...AND DECREASES IN BETWEEN.
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 /TONIGHT 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 /04Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...CONVECTION AND ASSOCIATED RESTRICTIONS WILL REMAIN POSSIBLE
THIS EVENING. WITH RAIN HAVING ALREADY OCCURRED...AND MORE
POSSIBLE...DAYBREAK MVFR FOG SEEMS LIKELY. MODEL TIME HEIGHTS
SUPPORT A CIG AT AROUND 6000 FT FOR MUCH OF THE FORECAST...BUT SHOW
SUBSTANTIAL MOISTURE MUCH LOWER...AND DAYBREAK FOG MAY BE
ACCOMPANIED BY AN MVFR CIG...AND PERHAPS EVEN LOWER. ANOTHER ROUND
OF CONVECTION IS EXPECTED WEDNESDAY AFTERNOON AS THE PATTERN CHANGES
LITTLE. LIGHT WINDS WILL GENERALLY FAVOR THE S.
ELSEWHERE...CONVECTION AND ASSOCIATED RESTRICTIONS CANNOT BE RULED OUT
THIS EVENING...ALTHOUGH THE BEST COVERAGE OS EAST OF THE FOOTHILLS.
DAYBREAK FOG IS LIKELY...AS MANY SITES HAD RAIN OR MAY RECEIVE
SOME THIS EVENING...AND GUIDANCE IS LEANING IN THAT DIRECTION. THE
WORST RESTRICTIONS WOULD BE AT KAVL AND KHKY. MODEL TIME HEIGHTS
FAVOR LOW VFR CIGS AT AROUND 4500 TO 6000 FEET...BUT ENOUGH LOW
LEVEL MOISTURE IS PRESENT TO ALLOW FOR DAYBREAK MVFR CIGS WHERE FOG
OCCURS...AND POSSIBLE EVEN LOWER CIGS. YET ANOTHER AROUND OF
CONVECTION IS EXPECTED WEDNESDAY AFTERNOON IN A PERSISTENT UPPER
LEVEL PATTERN. LIGHT WINDS WILL FAVOR THE S.
OUTLOOK...AN UPPER LEVEL TROUGH WILL AMPLIFY ACROSS THE ATLANTIC
STATES LATE IN THE WEEK...WITH THE LIKELY PASSAGE OF A COLD FRONT ON
FRIDAY. THE POTENTIAL FOR CONVECTION WILL INCREASE THROUGH
FRIDAY...THEN DECREASE BEHIND THE FRONT ON SATURDAY.
CONFIDENCE TABLE...
04-10Z 10-16Z 16-22Z 22-00Z
KCLT HIGH 100% HIGH 97% HIGH 87% HIGH 100%
KGSP HIGH 100% HIGH 100% MED 78% HIGH 100%
KAVL HIGH 100% MED 63% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 83% HIGH 81% HIGH 100%
KGMU HIGH 100% HIGH 100% MED 78% 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.
&&
$$
SYNOPSIS...JPT
NEAR TERM...NED
SHORT TERM...JDL
LONG TERM...JPT
AVIATION...JAT
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
329 PM CDT WED JUL 29 2015
.DISCUSSION...
HOT AND HUMID CONDITIONS CONTINUE ACROSS MIDDLE TENNESSEE THIS
AFTERNOON AS THE SHOWERS AND THUNDERSTORMS THAT MOVED THROUGH THE
AREA EARLIER THIS MORNING LEFT QUITE THE SOUPY AIRMASS IN PLACE.
FOR THIS EVENING AND TONIGHT...STILL THINK A FEW ISOLATED SHOWERS
AND THUNDERSTORMS MAY DEVELOP...BUT WILL SIDE WITH THE HRRR AS MUCH
OF THE AREA WILL REMAIN DRY. A COLD FRONT WILL PUSH ACROSS MIDDLE
TENNESSEE OVERNIGHT BRINGING MUCH DRIER AIR...A VERY NICE CHANGE
IN TIME FOR THE WEEKEND.
THURSDAY THROUGH TUESDAY...A QUIET WEATHER PATTERN CAN BE
EXPECTED...ESPECIALLY FOR THE BEGINNING OF AUGUST...AS HIGH
PRESSURE BUILDS OVER THE REGION. CONDITIONS WILL NOT BE QUITE AS
HUMID ALTHOUGH HIGHS WILL STILL REACH THE LOWER 90S IN MOST
LOCATIONS. BIGGEST DIFFERENCE WILL BE FELT WITH LOW TEMPERATURES
WITH MID TO UPPER 60S EXPECTED INSTEAD OF THE LOWER TO MID 70S.
TEMPERATURES WILL SLOWLY BEGIN TO INCREASE AFTER THE
WEEKEND...ALONG WITH HUMIDITY VALUES TOO.
BY THE MIDDLE OF NEXT WEEK...UPPER LEVEL PATTERN WILL AGAIN SHIFT
TO NORTHWEST FLOW AS THE SURFACE HIGH LOSES ITS STRONGHOLD. AS A
RESULT...THUNDERSTORM CHANCES WILL INCREASE TUESDAY NIGHT AND
LIKELY REMAIN IN THE FORECAST THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 75 90 66 90 / 20 10 0 0
CLARKSVILLE 71 88 65 89 / 20 0 0 0
CROSSVILLE 72 85 64 84 / 30 20 0 0
COLUMBIA 75 90 66 90 / 20 20 0 0
LAWRENCEBURG 74 90 66 89 / 20 20 0 0
WAVERLY 73 89 67 89 / 20 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TNZ005>007-023>027-
056>061-093>095.
&&
$$
HURLEY
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1232 PM CDT WED JUL 29 2015
.DISCUSSION...
UPDATED FOR AVIATION DISCUSSION FOR 18Z TAFS
&&
.PREV DISCUSSION... /ISSUED 1026 AM CDT WED JUL 29 2015/
UPDATE...
BROKEN/OVERCAST MIDLEVEL ALTOCUMULUS DECK WAS SLOWLY DRIFTING
SOUTH THROUGH SOUTHWEST TN AND PORTIONS OF NORTH MS. EVEN WHERE
SKIES WERE CLOUDY...HEAT INDICES WERE NEAR 100 AT 10 AM CDT.
FOR THE MORNING UPDATE...HAVE TRIMMED RAIN CHANCES BACK TO BELOW
MENTIONABLE LEVELS UNDER THE UPPER RIDGE/WEST OF THE TN RIVER
VALLEY. HRRR WAS OVERDONE WITH RESPECT TO MORNING STORMS OVER
NORTHEAST MS... BUT EVEN IT WAS PREDOMINATELY DRY WEST OF THE MS
RIVER THIS AFTERNOON. THE 12Z NAM AND 06Z SHOWED NO QPF OVER ANY
OF THE MIDSOUTH TODAY. GIVEN 700MB TEMPS OF 12C TO 13C...THIS
SCENARIO ISN/T OUT OF THE QUESTION.
TEMPERATURE AND HEAT INDEX FORECAST APPEAR ON TRACK...WITH NO
ADJUSTMENTS NEEDED AT MIDMORNING.
PWB
PREV DISCUSSION... /ISSUED 341 AM CDT WED JUL 29 2015/
DISCUSSION...
ONE MORE DAY OF DANGEROUS HEAT AND HUMIDITY IS EXPECTED ON
WEDNESDAY WITH RELIEF COMING IN THE FORM OF A COLD FRONT MOVING
THROUGH THE MID-SOUTH LATE WEDNESDAY NIGHT/THURSDAY MORNING...
CURRENTLY...A VERY WARM NIGHT WAS ONGOING ACROSS THE MID-SOUTH
WITH TEMPERATURES NEAR 80 DEGREES AND DEWPOINTS IN THE MID TO
UPPER 70S. ALOFT...AN UPPER LEVEL RIDGE WAS ANCHORED ACROSS MUCH
OF THE SOUTHERN US. AT THE SURFACE...HIGH PRESSURE WAS IN PLACE
ACROSS MUCH OF THE SOUTHEASTERN US WITH A COLD FRONT ORIENTED SW
TO NE FROM THE TX PANHANDLE THROUGH NORTHERN MO/SRN WI. EARLIER IN
THE EVENING...A SUBSTANTIAL COMPLEX OF THUNDERSTORMS DEVELOPED
ACROSS PORTIONS OF MIDDLE TENNESSEE WHICH EXPELLED AN OUTFLOW
BOUNDARY SOUTHWEST INTO PORTIONS OF THE TENNESSEE RIVER VALLEY.
WHILE SURFACE WINDS ARE VARIABLE...THAT BOUNDARY IS LIKELY STILL
PRESENT THROUGH THE REGION BUT BECOMING MORE DIFFUSE WITH TIME.
FOR WEDNESDAY...EXCESSIVE HEAT IS STILL FORECAST...HOWEVER THERE
ARE A FEW COMPLICATING FACTORS. HI-RES MEMBERS INCLUDING THE NSSL
WRF AND THE HRRR DEVELOP THUNDERSTORMS EARLY IN THE DAY AS A WEAK
DISTURBANCE DIVES SOUTHEAST AROUND THE PERIPHERY OF THE SURFACE
RIDGE. THE AFOREMENTIONED OUTFLOW BOUNDARY MAY SERVE AS A FOCUS
FOR THIS DEVELOPMENT BUT THIS SOLUTION IS EXTREMELY UNCERTAIN AT
THIS POINT. IF IT WERE TO UNFOLD AS SUCH...PORTIONS OF WEST
TENNESSEE ALONG THE TN RIVER MAY NOT REACH HEAT ADVISORY CRITERIA
OWING TO CLOUD COVER/PRECIP. AT THIS POINT...DID NOT ADJUST THE
ADVISORY GIVEN THE AFOREMENTIONED UNCERTAINTY. BELIEVE THE HI-RES
SOLUTIONS TO BE MUCH TOO AGGRESSIVE WITH PRECIP DEVELOPMENT...BUT
IT IS WORTH MENTIONING.
FURTHER WEST TOWARD THE MS RIVER...EXCESSIVE HEAT WARNINGS REMAIN
IN EFFECT ACROSS E AND NE AR/NW MS/W TN WITH HIGH CONFIDENCE IN
DANGEROUS HEAT INDICES DEVELOPING FROM MIDDAY THROUGH EARLY
EVENING. MANY LOCATIONS WILL EXPERIENCE SEVERAL HOURS OF HEAT
INDICES BETWEEN 111 AND 114 DEGREES GIVEN THE EXTREMELY MOIST
BOUNDARY LAYER IN PLACE WITH DEWPOINTS IN THE MID AND UPPER 70S
AND TEMPERATURES IN THE UPPER 90S. PRECIPITATION IS NOT EXPECTED
TO HINDER SOLAR HEATING AND SHOULD HOLD OFF UNTIL THE EVENING
HOURS.
WEDNESDAY NIGHT...THE FRONTAL BOUNDARY APPROACHES FROM THE NORTH
BUT CONSIDERABLE UNCERTAINTY EXISTS WITH RESPECT TO COVERAGE OF
SHOWERS AND THUNDERSTORMS. THERE WILL LIKELY BE ISOLATED
DEVELOPMENT AFTER 00Z THURSDAY ALONG THE FRONT BUT PLACING THIS
DEVELOPMENT IS DIFFICULT AT THIS TIME. FOR NOW...SLIGHT CHANCE TO
CHANCE POPS WERE MAINTAINED TO ACCOUNT FOR THIS.
BY THURSDAY...THE FRONTAL BOUNDARY WILL CONTINUE TO PUSH SOUTH
WITH DRIER AIR ADVECTING INTO THE REGION. NORTHERN MISSISSIPPI MAY
STILL NEAR HEAT ADVISORY CRITERIA EARLIER IN THE DAY BUT EVEN THIS
SHOULD BE SHORT-LIVED AS CLOUD COVER AND SHOWERS/TSTORMS SHOULD
PROVIDE RELIEF DURING THE MID TO LATE AFTERNOON HOURS. BY THURSDAY
NIGHT...THE FRONT WILL HAVE CLEARED THE REGION LEAVING A MUCH MORE
PLEASANT AIRMASS IN PLACE WITH DEWPOINTS IN THE LOW TO MID 60S AND
TEMPERATURES IN THE UPPER 60S TO NEAR 70 THURSDAY NIGHT.
THROUGH THE WEEKEND...A SLOW WARMUP IS EXPECTED BUT SEVERAL DAYS
OF BEARABLE TEMPERATURES ARE FORECAST WITH LOWER HUMIDITY. THIS
PERIOD SHOULD ALSO BE DRY FOR THE ENTIRE REGION.
IN THE LONG-TERM...UPPER LEVEL RIDGING STRENGTHENS ACROSS THE
DESERT SOUTHWEST WITH A PERSISTENT AREA OF UPPER LEVEL LOW
PRESSURE ACROSS THE EAST-CENTRAL CANADIAN PROVINCES. THE MID-SOUTH
WILL FALL SOMEWHERE BETWEEN THESE TWO FEATURES WITH WARMING
TEMPERATURES ONCE AGAIN. A SLOW INCREASE IN HEIGHTS SUGGESTS THAT
ANOTHER WARM TO HOT PERIOD MAY DEVELOP BUT IT IS TOO SOON TO TELL
HOW HOT...BUT IT IS WORTH WATCHING.
TVT
&&
.AVIATION...
18Z TAF CYCLE
VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD. THERE CLOUD BE
A FEW THUNDERSTORMS ACROSS WEST TENNESSEE AND NORTHEAST
MISSISSIPPI THIS AFTERNOON. INCLUDED VCTS AT BOTH KMKL AND KTUP
TO ACCOUNT FOR THIS. WINDS SHOULD BE LIGHT THROUGHOUT THE PERIOD.
TLSJR
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR CLAY-
CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-
MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DUNKLIN-
PEMISCOT.
MS...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR COAHOMA-
DESOTO-MARSHALL-PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-ITAWAMBA-LAFAYETTE-LEE MS-MONROE-PONTOTOC-
PRENTISS-TIPPAH-TISHOMINGO-UNION-YALOBUSHA.
TN...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DYER-
FAYETTE-LAKE-LAUDERDALE-OBION-SHELBY-TIPTON.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR BENTON TN-CARROLL-
CHESTER-CROCKETT-DECATUR-GIBSON-HARDEMAN-HARDIN-HAYWOOD-
HENDERSON-HENRY-MADISON-MCNAIRY-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1026 AM CDT WED JUL 29 2015
.UPDATE...
BROKEN/OVERCAST MIDLEVEL ALTOCUMULUS DECK WAS SLOWLY DRIFTING
SOUTH THROUGH SOUTHWEST TN AND PORTIONS OF NORTH MS. EVEN WHERE
SKIES WERE CLOUDY...HEAT INDICES WERE NEAR 100 AT 10 AM CDT.
FOR THE MORNING UPDATE...HAVE TRIMMED RAIN CHANCES BACK TO BELOW
MENTIONABLE LEVELS UNDER THE UPPER RIDGE/WEST OF THE TN RIVER
VALLEY. HRRR WAS OVERDONE WITH RESPECT TO MORNING STORMS OVER
NORTHEAST MS... BUT EVEN IT WAS PREDOMINATELY DRY WEST OF THE MS
RIVER THIS AFTERNOON. THE 12Z NAM AND 06Z SHOWED NO QPF OVER ANY
OF THE MIDSOUTH TODAY. GIVEN 700MB TEMPS OF 12C TO 13C...THIS
SCENARIO ISN/T OUT OF THE QUESTION.
TEMPERATURE AND HEAT INDEX FORECAST APPEAR ON TRACK...WITH NO
ADJUSTMENTS NEEDED AT MIDMORNING.
PWB
&&
.PREV DISCUSSION... /ISSUED 711 AM CDT WED JUL 29 2015/
UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 341 AM CDT WED JUL 29 2015/
DISCUSSION...
ONE MORE DAY OF DANGEROUS HEAT AND HUMIDITY IS EXPECTED ON
WEDNESDAY WITH RELIEF COMING IN THE FORM OF A COLD FRONT MOVING
THROUGH THE MID-SOUTH LATE WEDNESDAY NIGHT/THURSDAY MORNING...
CURRENTLY...A VERY WARM NIGHT WAS ONGOING ACROSS THE MID-SOUTH
WITH TEMPERATURES NEAR 80 DEGREES AND DEWPOINTS IN THE MID TO
UPPER 70S. ALOFT...AN UPPER LEVEL RIDGE WAS ANCHORED ACROSS MUCH
OF THE SOUTHERN US. AT THE SURFACE...HIGH PRESSURE WAS IN PLACE
ACROSS MUCH OF THE SOUTHEASTERN US WITH A COLD FRONT ORIENTED SW
TO NE FROM THE TX PANHANDLE THROUGH NORTHERN MO/SRN WI. EARLIER IN
THE EVENING...A SUBSTANTIAL COMPLEX OF THUNDERSTORMS DEVELOPED
ACROSS PORTIONS OF MIDDLE TENNESSEE WHICH EXPELLED AN OUTFLOW
BOUNDARY SOUTHWEST INTO PORTIONS OF THE TENNESSEE RIVER VALLEY.
WHILE SURFACE WINDS ARE VARIABLE...THAT BOUNDARY IS LIKELY STILL
PRESENT THROUGH THE REGION BUT BECOMING MORE DIFFUSE WITH TIME.
FOR WEDNESDAY...EXCESSIVE HEAT IS STILL FORECAST...HOWEVER THERE
ARE A FEW COMPLICATING FACTORS. HI-RES MEMBERS INCLUDING THE NSSL
WRF AND THE HRRR DEVELOP THUNDERSTORMS EARLY IN THE DAY AS A WEAK
DISTURBANCE DIVES SOUTHEAST AROUND THE PERIPHERY OF THE SURFACE
RIDGE. THE AFOREMENTIONED OUTFLOW BOUNDARY MAY SERVE AS A FOCUS
FOR THIS DEVELOPMENT BUT THIS SOLUTION IS EXTREMELY UNCERTAIN AT
THIS POINT. IF IT WERE TO UNFOLD AS SUCH...PORTIONS OF WEST
TENNESSEE ALONG THE TN RIVER MAY NOT REACH HEAT ADVISORY CRITERIA
OWING TO CLOUD COVER/PRECIP. AT THIS POINT...DID NOT ADJUST THE
ADVISORY GIVEN THE AFOREMENTIONED UNCERTAINTY. BELIEVE THE HI-RES
SOLUTIONS TO BE MUCH TOO AGGRESSIVE WITH PRECIP DEVELOPMENT...BUT
IT IS WORTH MENTIONING.
FURTHER WEST TOWARD THE MS RIVER...EXCESSIVE HEAT WARNINGS REMAIN
IN EFFECT ACROSS E AND NE AR/NW MS/W TN WITH HIGH CONFIDENCE IN
DANGEROUS HEAT INDICES DEVELOPING FROM MIDDAY THROUGH EARLY
EVENING. MANY LOCATIONS WILL EXPERIENCE SEVERAL HOURS OF HEAT
INDICES BETWEEN 111 AND 114 DEGREES GIVEN THE EXTREMELY MOIST
BOUNDARY LAYER IN PLACE WITH DEWPOINTS IN THE MID AND UPPER 70S
AND TEMPERATURES IN THE UPPER 90S. PRECIPITATION IS NOT EXPECTED
TO HINDER SOLAR HEATING AND SHOULD HOLD OFF UNTIL THE EVENING
HOURS.
WEDNESDAY NIGHT...THE FRONTAL BOUNDARY APPROACHES FROM THE NORTH
BUT CONSIDERABLE UNCERTAINTY EXISTS WITH RESPECT TO COVERAGE OF
SHOWERS AND THUNDERSTORMS. THERE WILL LIKELY BE ISOLATED
DEVELOPMENT AFTER 00Z THURSDAY ALONG THE FRONT BUT PLACING THIS
DEVELOPMENT IS DIFFICULT AT THIS TIME. FOR NOW...SLIGHT CHANCE TO
CHANCE POPS WERE MAINTAINED TO ACCOUNT FOR THIS.
BY THURSDAY...THE FRONTAL BOUNDARY WILL CONTINUE TO PUSH SOUTH
WITH DRIER AIR ADVECTING INTO THE REGION. NORTHERN MISSISSIPPI MAY
STILL NEAR HEAT ADVISORY CRITERIA EARLIER IN THE DAY BUT EVEN THIS
SHOULD BE SHORT-LIVED AS CLOUD COVER AND SHOWERS/TSTORMS SHOULD
PROVIDE RELIEF DURING THE MID TO LATE AFTERNOON HOURS. BY THURSDAY
NIGHT...THE FRONT WILL HAVE CLEARED THE REGION LEAVING A MUCH MORE
PLEASANT AIRMASS IN PLACE WITH DEWPOINTS IN THE LOW TO MID 60S AND
TEMPERATURES IN THE UPPER 60S TO NEAR 70 THURSDAY NIGHT.
THROUGH THE WEEKEND...A SLOW WARMUP IS EXPECTED BUT SEVERAL DAYS
OF BEARABLE TEMPERATURES ARE FORECAST WITH LOWER HUMIDITY. THIS
PERIOD SHOULD ALSO BE DRY FOR THE ENTIRE REGION.
IN THE LONG-TERM...UPPER LEVEL RIDGING STRENGTHENS ACROSS THE
DESERT SOUTHWEST WITH A PERSISTENT AREA OF UPPER LEVEL LOW
PRESSURE ACROSS THE EAST-CENTRAL CANADIAN PROVINCES. THE MID-SOUTH
WILL FALL SOMEWHERE BETWEEN THESE TWO FEATURES WITH WARMING
TEMPERATURES ONCE AGAIN. A SLOW INCREASE IN HEIGHTS SUGGESTS THAT
ANOTHER WARM TO HOT PERIOD MAY DEVELOP BUT IT IS TOO SOON TO TELL
HOW HOT...BUT IT IS WORTH WATCHING.
TVT
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD. THERE SHOULD BE
A FEW SHOWERS AND THUNDERSTORMS ACROSS WEST TENNESSEE AND
NORTHEAST MISSISSIPPI LATER TODAY. VCTS HAS BEEN INCLUDED FOR BOTH
KMKL AND KTUP WITH THIS IN MIND. ALL CONVECTION SHOULD DIMINISH OR
COVERAGE SHOULD BECOME TOO LOW TO KEEP ANY MENTION IN TAFS
TONIGHT. WINDS SHOULD BE LIGHT WESTERLY AT 7 KTS OR LESS BECOMING
LIGHT NORTHEASTERLY BEHIND A FRONTAL PASSAGE TONIGHT.
JLH
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR CLAY-
CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-
MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DUNKLIN-
PEMISCOT.
MS...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR COAHOMA-
DESOTO-MARSHALL-PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-ITAWAMBA-LAFAYETTE-LEE MS-MONROE-PONTOTOC-
PRENTISS-TIPPAH-TISHOMINGO-UNION-YALOBUSHA.
TN...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DYER-
FAYETTE-LAKE-LAUDERDALE-OBION-SHELBY-TIPTON.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR BENTON TN-CARROLL-
CHESTER-CROCKETT-DECATUR-GIBSON-HARDEMAN-HARDIN-HAYWOOD-
HENDERSON-HENRY-MADISON-MCNAIRY-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
711 AM CDT WED JUL 29 2015
.UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 341 AM CDT WED JUL 29 2015/
DISCUSSION...
ONE MORE DAY OF DANGEROUS HEAT AND HUMIDITY IS EXPECTED ON
WEDNESDAY WITH RELIEF COMING IN THE FORM OF A COLD FRONT MOVING
THROUGH THE MID-SOUTH LATE WEDNESDAY NIGHT/THURSDAY MORNING...
CURRENTLY...A VERY WARM NIGHT WAS ONGOING ACROSS THE MID-SOUTH
WITH TEMPERATURES NEAR 80 DEGREES AND DEWPOINTS IN THE MID TO
UPPER 70S. ALOFT...AN UPPER LEVEL RIDGE WAS ANCHORED ACROSS MUCH
OF THE SOUTHERN US. AT THE SURFACE...HIGH PRESSURE WAS IN PLACE
ACROSS MUCH OF THE SOUTHEASTERN US WITH A COLD FRONT ORIENTED SW
TO NE FROM THE TX PANHANDLE THROUGH NORTHERN MO/SRN WI. EARLIER IN
THE EVENING...A SUBSTANTIAL COMPLEX OF THUNDERSTORMS DEVELOPED
ACROSS PORTIONS OF MIDDLE TENNESSEE WHICH EXPELLED AN OUTFLOW
BOUNDARY SOUTHWEST INTO PORTIONS OF THE TENNESSEE RIVER VALLEY.
WHILE SURFACE WINDS ARE VARIABLE...THAT BOUNDARY IS LIKELY STILL
PRESENT THROUGH THE REGION BUT BECOMING MORE DIFFUSE WITH TIME.
FOR WEDNESDAY...EXCESSIVE HEAT IS STILL FORECAST...HOWEVER THERE
ARE A FEW COMPLICATING FACTORS. HI-RES MEMBERS INCLUDING THE NSSL
WRF AND THE HRRR DEVELOP THUNDERSTORMS EARLY IN THE DAY AS A WEAK
DISTURBANCE DIVES SOUTHEAST AROUND THE PERIPHERY OF THE SURFACE
RIDGE. THE AFOREMENTIONED OUTFLOW BOUNDARY MAY SERVE AS A FOCUS
FOR THIS DEVELOPMENT BUT THIS SOLUTION IS EXTREMELY UNCERTAIN AT
THIS POINT. IF IT WERE TO UNFOLD AS SUCH...PORTIONS OF WEST
TENNESSEE ALONG THE TN RIVER MAY NOT REACH HEAT ADVISORY CRITERIA
OWING TO CLOUD COVER/PRECIP. AT THIS POINT...DID NOT ADJUST THE
ADVISORY GIVEN THE AFOREMENTIONED UNCERTAINTY. BELIEVE THE HI-RES
SOLUTIONS TO BE MUCH TOO AGGRESSIVE WITH PRECIP DEVELOPMENT...BUT
IT IS WORTH MENTIONING.
FURTHER WEST TOWARD THE MS RIVER...EXCESSIVE HEAT WARNINGS REMAIN
IN EFFECT ACROSS E AND NE AR/NW MS/W TN WITH HIGH CONFIDENCE IN
DANGEROUS HEAT INDICES DEVELOPING FROM MIDDAY THROUGH EARLY
EVENING. MANY LOCATIONS WILL EXPERIENCE SEVERAL HOURS OF HEAT
INDICES BETWEEN 111 AND 114 DEGREES GIVEN THE EXTREMELY MOIST
BOUNDARY LAYER IN PLACE WITH DEWPOINTS IN THE MID AND UPPER 70S
AND TEMPERATURES IN THE UPPER 90S. PRECIPITATION IS NOT EXPECTED
TO HINDER SOLAR HEATING AND SHOULD HOLD OFF UNTIL THE EVENING
HOURS.
WEDNESDAY NIGHT...THE FRONTAL BOUNDARY APPROACHES FROM THE NORTH
BUT CONSIDERABLE UNCERTAINTY EXISTS WITH RESPECT TO COVERAGE OF
SHOWERS AND THUNDERSTORMS. THERE WILL LIKELY BE ISOLATED
DEVELOPMENT AFTER 00Z THURSDAY ALONG THE FRONT BUT PLACING THIS
DEVELOPMENT IS DIFFICULT AT THIS TIME. FOR NOW...SLIGHT CHANCE TO
CHANCE POPS WERE MAINTAINED TO ACCOUNT FOR THIS.
BY THURSDAY...THE FRONTAL BOUNDARY WILL CONTINUE TO PUSH SOUTH
WITH DRIER AIR ADVECTING INTO THE REGION. NORTHERN MISSISSIPPI MAY
STILL NEAR HEAT ADVISORY CRITERIA EARLIER IN THE DAY BUT EVEN THIS
SHOULD BE SHORT-LIVED AS CLOUD COVER AND SHOWERS/TSTORMS SHOULD
PROVIDE RELIEF DURING THE MID TO LATE AFTERNOON HOURS. BY THURSDAY
NIGHT...THE FRONT WILL HAVE CLEARED THE REGION LEAVING A MUCH MORE
PLEASANT AIRMASS IN PLACE WITH DEWPOINTS IN THE LOW TO MID 60S AND
TEMPERATURES IN THE UPPER 60S TO NEAR 70 THURSDAY NIGHT.
THROUGH THE WEEKEND...A SLOW WARMUP IS EXPECTED BUT SEVERAL DAYS
OF BEARABLE TEMPERATURES ARE FORECAST WITH LOWER HUMIDITY. THIS
PERIOD SHOULD ALSO BE DRY FOR THE ENTIRE REGION.
IN THE LONG-TERM...UPPER LEVEL RIDGING STRENGTHENS ACROSS THE
DESERT SOUTHWEST WITH A PERSISTENT AREA OF UPPER LEVEL LOW
PRESSURE ACROSS THE EAST-CENTRAL CANADIAN PROVINCES. THE MID-SOUTH
WILL FALL SOMEWHERE BETWEEN THESE TWO FEATURES WITH WARMING
TEMPERATURES ONCE AGAIN. A SLOW INCREASE IN HEIGHTS SUGGESTS THAT
ANOTHER WARM TO HOT PERIOD MAY DEVELOP BUT IT IS TOO SOON TO TELL
HOW HOT...BUT IT IS WORTH WATCHING.
TVT
&&
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD. THERE SHOULD BE
A FEW SHOWERS AND THUNDERSTORMS ACROSS WEST TENNESSEE AND
NORTHEAST MISSISSIPPI LATER TODAY. VCTS HAS BEEN INCLUDED FOR BOTH
KMKL AND KTUP WITH THIS IN MIND. ALL CONVECTION SHOULD DIMINISH OR
COVERAGE SHOULD BECOME TOO LOW TO KEEP ANY MENTION IN TAFS
TONIGHT. WINDS SHOULD BE LIGHT WESTERLY AT 7 KTS OR LESS BECOMING
LIGHT NORTHEASTERLY BEHIND A FRONTAL PASSAGE TONIGHT.
JLH
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR CLAY-
CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-
MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DUNKLIN-
PEMISCOT.
MS...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR COAHOMA-
DESOTO-MARSHALL-PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-ITAWAMBA-LAFAYETTE-LEE MS-MONROE-PONTOTOC-
PRENTISS-TIPPAH-TISHOMINGO-UNION-YALOBUSHA.
TN...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DYER-
FAYETTE-LAKE-LAUDERDALE-OBION-SHELBY-TIPTON.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR BENTON TN-CARROLL-
CHESTER-CROCKETT-DECATUR-GIBSON-HARDEMAN-HARDIN-HAYWOOD-
HENDERSON-HENRY-MADISON-MCNAIRY-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
341 AM CDT WED JUL 29 2015
.DISCUSSION...
ONE MORE DAY OF DANGEROUS HEAT AND HUMIDITY IS EXPECTED ON
WEDNESDAY WITH RELIEF COMING IN THE FORM OF A COLD FRONT MOVING
THROUGH THE MID-SOUTH LATE WEDNESDAY NIGHT/THURSDAY MORNING...
CURRENTLY...A VERY WARM NIGHT WAS ONGOING ACROSS THE MID-SOUTH
WITH TEMPERATURES NEAR 80 DEGREES AND DEWPOINTS IN THE MID TO
UPPER 70S. ALOFT...AN UPPER LEVEL RIDGE WAS ANCHORED ACROSS MUCH
OF THE SOUTHERN US. AT THE SURFACE...HIGH PRESSURE WAS IN PLACE
ACROSS MUCH OF THE SOUTHEASTERN US WITH A COLD FRONT ORIENTED SW
TO NE FROM THE TX PANHANDLE THROUGH NORTHERN MO/SRN WI. EARLIER IN
THE EVENING...A SUBSTANTIAL COMPLEX OF THUNDERSTORMS DEVELOPED
ACROSS PORTIONS OF MIDDLE TENNESSEE WHICH EXPELLED AN OUTFLOW
BOUNDARY SOUTHWEST INTO PORTIONS OF THE TENNESSEE RIVER VALLEY.
WHILE SURFACE WINDS ARE VARIABLE...THAT BOUNDARY IS LIKELY STILL
PRESENT THROUGH THE REGION BUT BECOMING MORE DIFFUSE WITH TIME.
FOR WEDNESDAY...EXCESSIVE HEAT IS STILL FORECAST...HOWEVER THERE
ARE A FEW COMPLICATING FACTORS. HI-RES MEMBERS INCLUDING THE NSSL
WRF AND THE HRRR DEVELOP THUNDERSTORMS EARLY IN THE DAY AS A WEAK
DISTURBANCE DIVES SOUTHEAST AROUND THE PERIPHERY OF THE SURFACE
RIDGE. THE AFOREMENTIONED OUTFLOW BOUNDARY MAY SERVE AS A FOCUS
FOR THIS DEVELOPMENT BUT THIS SOLUTION IS EXTREMELY UNCERTAIN AT
THIS POINT. IF IT WERE TO UNFOLD AS SUCH...PORTIONS OF WEST
TENNESSEE ALONG THE TN RIVER MAY NOT REACH HEAT ADVISORY CRITERIA
OWING TO CLOUD COVER/PRECIP. AT THIS POINT...DID NOT ADJUST THE
ADVISORY GIVEN THE AFOREMENTIONED UNCERTAINTY. BELIEVE THE HI-RES
SOLUTIONS TO BE MUCH TOO AGGRESSIVE WITH PRECIP DEVELOPMENT...BUT
IT IS WORTH MENTIONING.
FURTHER WEST TOWARD THE MS RIVER...EXCESSIVE HEAT WARNINGS REMAIN
IN EFFECT ACROSS E AND NE AR/NW MS/W TN WITH HIGH CONFIDENCE IN
DANGEROUS HEAT INDICES DEVELOPING FROM MIDDAY THROUGH EARLY
EVENING. MANY LOCATIONS WILL EXPERIENCE SEVERAL HOURS OF HEAT
INDICES BETWEEN 111 AND 114 DEGREES GIVEN THE EXTREMELY MOIST
BOUNDARY LAYER IN PLACE WITH DEWPOINTS IN THE MID AND UPPER 70S
AND TEMPERATURES IN THE UPPER 90S. PRECIPITATION IS NOT EXPECTED
TO HINDER SOLAR HEATING AND SHOULD HOLD OFF UNTIL THE EVENING
HOURS.
WEDNESDAY NIGHT...THE FRONTAL BOUNDARY APPROACHES FROM THE NORTH
BUT CONSIDERABLE UNCERTAINTY EXISTS WITH RESPECT TO COVERAGE OF
SHOWERS AND THUNDERSTORMS. THERE WILL LIKELY BE ISOLATED
DEVELOPMENT AFTER 00Z THURSDAY ALONG THE FRONT BUT PLACING THIS
DEVELOPMENT IS DIFFICULT AT THIS TIME. FOR NOW...SLIGHT CHANCE TO
CHANCE POPS WERE MAINTAINED TO ACCOUNT FOR THIS.
BY THURSDAY...THE FRONTAL BOUNDARY WILL CONTINUE TO PUSH SOUTH
WITH DRIER AIR ADVECTING INTO THE REGION. NORTHERN MISSISSIPPI MAY
STILL NEAR HEAT ADVISORY CRITERIA EARLIER IN THE DAY BUT EVEN THIS
SHOULD BE SHORT-LIVED AS CLOUD COVER AND SHOWERS/TSTORMS SHOULD
PROVIDE RELIEF DURING THE MID TO LATE AFTERNOON HOURS. BY THURSDAY
NIGHT...THE FRONT WILL HAVE CLEARED THE REGION LEAVING A MUCH MORE
PLEASANT AIRMASS IN PLACE WITH DEWPOINTS IN THE LOW TO MID 60S AND
TEMPERATURES IN THE UPPER 60S TO NEAR 70 THURSDAY NIGHT.
THROUGH THE WEEKEND...A SLOW WARMUP IS EXPECTED BUT SEVERAL DAYS
OF BEARABLE TEMPERATURES ARE FORECAST WITH LOWER HUMIDITY. THIS
PERIOD SHOULD ALSO BE DRY FOR THE ENTIRE REGION.
IN THE LONG-TERM...UPPER LEVEL RIDGING STRENGTHENS ACROSS THE
DESERT SOUTHWEST WITH A PERSISTENT AREA OF UPPER LEVEL LOW
PRESSURE ACROSS THE EAST-CENTRAL CANADIAN PROVINCES. THE MID-SOUTH
WILL FALL SOMEWHERE BETWEEN THESE TWO FEATURES WITH WARMING
TEMPERATURES ONCE AGAIN. A SLOW INCREASE IN HEIGHTS SUGGESTS THAT
ANOTHER WARM TO HOT PERIOD MAY DEVELOP BUT IT IS TOO SOON TO TELL
HOW HOT...BUT IT IS WORTH WATCHING.
TVT
&&
.AVIATION...
06Z TAF CYCLE
PATCHY FOG MAY DEVELOP LATE TONIGHT PRODUCING TEMPORARY MVFR/IFR
CONDITIONS AT MKL AND MVFR CONDITIONS AT TUP. OTHERWISE...VFR
CONDITIONS EXPECTED TO PREVAIL AT SITES FOR MOST OF THE PERIOD.
VCTS POSSIBLE AT SITES AFTER 29/12Z AND AT LEAST THROUGH 30/02Z AS
AN UPPER LEVEL RIDGE BEGINS TO WEAKEN SLIGHTLY AND A WEAK COLD
FRONT ENTERS THE LOWER MISSISSIPPI VALLEY.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR CLAY-
CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-
MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DUNKLIN-
PEMISCOT.
MS...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR COAHOMA-
DESOTO-MARSHALL-PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-ITAWAMBA-LAFAYETTE-LEE MS-MONROE-PONTOTOC-
PRENTISS-TIPPAH-TISHOMINGO-UNION-YALOBUSHA.
TN...EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR DYER-
FAYETTE-LAKE-LAUDERDALE-OBION-SHELBY-TIPTON.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR BENTON TN-CARROLL-
CHESTER-CROCKETT-DECATUR-GIBSON-HARDEMAN-HARDIN-HAYWOOD-
HENDERSON-HENRY-MADISON-MCNAIRY-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1144 PM CDT TUE JUL 28 2015
.AVIATION 06Z DISCUSSION...
CURRENT DEWPOINT SPREADS ARE RATHER LOW AND RANGE BETWEEN 1F AND
3F ACROSS MUCH OF THE AREA. BROKEN DECK...MOSTLY MID LEVEL WILL
PERSIST THROUGH MUCH OF THE NIGHT. HOWEVER...FOG MAY RED VSBYS
DOWN TO 3SM AT TIMES TOWARD 12Z.
CAPE/CAP RATIO TO BECOME QUITE FAVORABLE ONCE AGAIN ON WED AFT.
CATALYTIC IMPULSES MAY BE HARDER TO COME BY...HOWEVER...AS THE
UPPER HIGH IS IN CLOSER PROXIMITY. STILL THOUGH...ISOL TO SCT ACTIVITY
WILL LIKELY DEVELOP AFT 18Z. WILL INCLUDE PROB 30S FOR CKV AND
BNA. SOME STORMS MAY BE STRONG WITH GUSTY WINDS POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 906 PM CDT TUE JUL 28 2015/
UPDATE...
BEST INSTABILITY CONTINUING TO REMAIN ACROSS LOCATIONS APPROACHING
THE TN RIVER VALLEY REGION. ALTHOUGH CONVECTION IS WEAKENING...
WITH A BROAD AREA OF SHWRS...WITH SOME EMBEDDED TSTMS...REACHING
AS FAR E AS THE I-65 CORRIDOR AROUND 02Z...AND THE LATEST HRRR
MODEL INITIALIZING THIS OVERALL WX PATTERN BETTER...WILL GO AHEAD
WITH INCREASING SHWR/TSTM CHANCES ACROSS THESE AREAS THRU AT LEAST
MIDNIGHT...WITH NUMEROUS SHWRS/TSTMS POSSIBLE AS ONE APPROACHES
THE TN RIVER VALLEY REGION. BELIEVE THRU THE FIRST PART OF THE
EARLY MORNING HRS THAT AT LEAST SCT SHWRS...WITH SOME ISO
TSTMS...AROUND UPPER LEVEL RIDGE PERIPHERY...WILL BE POSSIBLE...
AND THUS WILL MENTION ALSO. WHILE MAKING THESE CHANGES...TWEAKED
HRLY TEMP...DEWPOINT...SKY CONDITION...AND WIND SPEED/DIRECTION GRIDS.
PREV DISCUSSION.../ISSUED 750 PM CDT TUE JUL 28 2015/
UPDATE...
HAVE UPDATED THE SUITE OF FORECAST PRODUCTS TO REMOVE MENTION OF
LATE AFTERNOON ZONE GROUPING IN ZONE FORECAST PRODUCT AND ALL
REFERENCES TO HEAT ADVISORY THAT EXPIRED AT 7 PM THIS EVENING.
WILL ALSO UPDATE THE HAZARDOUS WEATHER OUTLOOK PRODUCT TO DO
THE SAME. PER REGIONAL RADAR TRENDS...WITH SHWRS/TSTMS MOVING IN
FROM THE NW INTO LOCATIONS N OF I-40 AND W OF 1-65...AROUND
PERIPHERY OF UPPER LEVEL RIDGING DYNAMICS...WILL KEEP CHANCE POPS
ACROSS THIS REGION THRU THE MID EVENING HRS...BUT WITH DIURNAL
INFLUENCES GRADUALLY WEAKENING...DUE EXPECT AN OVERALL TREND OF
WEAKENING SHWRS/TSTMS THRU THE MID EVENING HRS ALONG WITH A
DECREASING TREND IN AREAL COVERAGE. THIS REASONING SUPPORTED BY
CONSENSUS OF SHORT RANGE MODEL SOLUTIONS. WILL KEEP A SLIGHT
CHANCE OF SHWRS/TSTMS ACROSS THE REST OF THE MID STATE THRU THE
EVENING HRS. EVEN THOUGH THERE IS SOME INDICATION IN SHORT RANGE
MODELS FOR A PREFERENCE FOR SHWR/TSTM ACTIVITY ACROSS WRN PORTIONS
OF THE MID STATE AFTER MIDNIGHT...ONLY EXPECTING ISO SHWRS/TSTMS
AT BEST...AND WILL THUS ADDRESS ALL AREAS ACROSS THE MID STATE
EXPERIENCING A SLIGHT CHANCE OF SHWRS/TSTMS AFTER MIDNIGHT. ALSO
TWEAKED HRLY TEMP...DEWPOINT...SKY CONDITION...AND WIND SPEED/DIRECTION
GRIDS. CURRENT TEMPS TRENDS SEEM IN LINE WITH FORECASTED LOW VALUES
EXPECTED OVERNIGHT AND THUS NO CHANGES NEEDED.
PREV DISCUSSION.../ISSUED 615 PM CDT TUE JUL 28 2015/
AVIATION 00Z DISCUSSION...
IMPULSE MOVING SOUTHWARD THROUGH THE MID STATE THIS EVENING. NVA
SHOULD MOVE IN AFT 03Z AND END THE OVERNIGHT CONVECTION. HRRR
CONCURS WITH RAIN FREE CONDITIONS BY 5Z. WILL OPT TO BE A LITTLE
MORE BULLISH WITH THE FOG POTENTIAL AND LOWER THE TEMPORARY VSBY
REDUCTIONS. MUCH OF THE AREA IS RAIN COOLED AND DEWPOINT SPREADS
ARE RATHER LOW.
UPPER HIGH MAY BE IN CLOSER PROXIMITY FOR TOMORROW. HOWEVER...CAPE
TO CAP RATIOS WILL BECOME FAVORABLE ONCE AGAIN IN THE AFT. WILL
INCLUDE VCNTY/CONVECTION IN TAFS AFT 18Z.
PREV DISCUSSION.../ISSUED 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 / 60 30 40 10
CROSSVILLE 71 87 72 84 / 20 30 40 50
COLUMBIA 75 93 74 91 / 60 30 40 40
LAWRENCEBURG 75 90 73 90 / 60 30 40 50
WAVERLY 75 95 73 88 / 60 30 40 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
937 PM CDT THU JUL 30 2015
.UPDATE...LEADING EDGE OF THE MOISTURE PLUME FROM THE EAST HAS
ARRIVED INTO THE FAR EASTERN CWA THIS EVENING. HOWEVER...A GRADUAL
DOWNWARD TREND IN CONVECTIVE ACTIVITY WILL TAKE PLACE THROUGH THE
REMAINDER OF THE LATE EVENING WITH LOSS OF HEATING. VERY MINOR
EDITS MADE TO HOURLY T/TD/APPARENT T GRIDS BASED ON TRENDS. NO
OTHER UPDATES PLANNED THIS EVENING. DEEPER MOISTURE CONTINUES TO
MOVE WEST AND SOUTHWEST INTO THE CWA OVERNIGHT AND FRIDAY. WITH
DE-STABILIZATION TOMORROW AFTERNOON EXPECT ISOLATED TO WIDELY
SCATTERED SHOWERS AND THUNDERSTORMS OVER THE REGION. A FEW STORMS
COULD PRODUCE STRONGER DOWNDRAFTS AND WIND GUSTS GIVEN MODEL
FORECAST SOUNDINGS...AND MENTIONED IN HWO.
&&
.PREV DISCUSSION... /ISSUED 625 PM CDT THU JUL 30 2015/
AVIATION...
/00Z TAFS/
VFR CONDITIONS ARE EXPECTED ACROSS AREA SITES THROUGH FRIDAY
AFTERNOON. WINDS WILL BE FROM THE EAST AND SOUTHEAST 5 TO 10 KNOTS
THIS EVENING...BECOMING LIGHT AND VARIABLE OVERNIGHT AND PICKING
BACK UP TO 10 KNOTS FRIDAY AFTERNOON WITH HIGHER GUSTS MAINLY
ACROSS THE RIO GRANDE PLAINS. A SURGE OF LOW TO MID LEVEL MOISTURE
IS FORECAST TO PUSH ACROSS THE EASTERN HALF OF SOUTH CENTRAL TEXAS
FRIDAY AFTERNOON AND EVENING. A FEW SHOWERS AND EVEN AN ISOLATED
THUNDERSTORM COULD POP ALONG THE I-35 SITES MID/LATE FRIDAY
AFTERNOON. THIS ACTIVITY SHOULD COME TO AN END SHORTLY AFTER
SUNSET.
PREV DISCUSSION... /ISSUED 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...17
SYNOPTIC/GRIDS...RUNYEN
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
912 PM CDT THU JUL 30 2015
.DISCUSSION...
SHOWERS AND THUNDERSTORMS STILL DRIFTING DOWN INTO NE ZONES AT
THIS HOUR. ANOTHER IMPORTANT FEATURE...RADAR SHOWING OUTFLOW FROM
LOUISIANA CONVECTION MOVING IN FROM THE EAST. THIS OUTFLOW TO
BRING SOME GUSTY EAST AND NORTHEAST WINDS SHORTLY TO GALVESTON BAY
AND EASTERN COASTAL GULF WATERS. WIND GUSTS WERE AS HIGH AS 40
KNOTS OVER COASTAL LOUISIANA...LIKELY 30 KNOTS OR SO FOR SOME
AREAS NOW. HAVE ISSUED A MARINE WEATHER STATEMENT TO GIVE A HEADS
UP FOR THIS FEATURE AND ADJUSTED WIND GRIDS AS WELL.
OVENRIGHT...EXPECT A CONTINUED SLOW WEAKENING TREND IN SHOWER AND
THUNDERSTORM ACTIVITY OVER LAND...BUT CANT RULE OUT AN ISOLATED
SHOWER OR THUNDERSTORM ANYWHERE GIVEN THE AIRMASS CATEGORIZED BY
DEEPER MOISTURE. FOR COASTAL AREAS WILL LIKELY SEE SQUALL LINE
BRUSH AT LEAST OUTER WATERS...BUT OUTFLOW WILL MOVE FROM NE TO SW
ALONG THE COAST WITH SOME ADDITIONAL DEVELOPMENT POSSIBLE. HAVE
BUMPED UP POPS FOR COASTAL WATERS TO COVER THIS. HIGH RESOLUTION
RAPID REFRESH SUPPORTS THIS SCENARIO. 46
&&
.PREV DISCUSSION... /ISSUED 623 PM CDT THU JUL 30 2015/
DISCUSSION...
SEE 00Z AVIATION DISCUSSION.
AVIATION...
SHRA/TSRA APPROACHING KCXO/KIAH AND WILL LIKELY IMPACT THESE TAF
SITS FOR THE NEXT HOUR OR SO. COULD GET SOME BRIEF GUSTY WINDS
WITH THESE STORMS. FELT THE RAP HAS VERIFIED BEST FROM YESTERDAY
AND WILL LEAN TOWARD THE RAP/GFS FOR TONIGHT AND FRIDAY. FEEL
SHRA/TSRA WILL END BETWEEN 02-03Z WITH ONLY ISOLATED SHRA
THEREAFTER. THE RAP BEGINS TO BRINGS THINGS BACK UP AROUND 12Z SO
WILL RESTART VCSH BETWEEN 11-13Z AREAWIDE. DRY AIR WILL FILTER
INTO THE AREA FROM THE NE ON FRIDAY AND WILL END PRECIP FROM NE TO
SW DURING THE AFTN. NUMEROUS OUTFLOW BOUNDARIES AND A WEAK
PRESSURE GRADIENT MAKES FCSTING WIND DIRECTION DIFFICULT. 43
PREV DISCUSSION... /ISSUED 304 PM CDT THU JUL 30 2015/
DISCUSSION...
SCT CONVECTION IS OCCURRING ACROSS NORTHERN AND EASTERN AREAS THIS
AFTERNOON. THIS ACTIVITY IS MOVING SOUTHWEST...SO CENTRAL AREAS
WILL LIKELY SEE SCT CONVECTION AS WELL LATER THIS AFTERNOON AND
EVENING. NORTHERN AND EASTERN AREAS ARE MOIST AND UNSTABLE...SO
ISOLATED STRONG STORMS ARE POSSIBLE. MAX TEMPS ARE AROUND 100
ACROSS FAR INLAND AREAS...UPPER 90S CENTRAL AREAS...AND LOWER TO
MID 90S COAST. HEAT INDICES REMAIN IN THE 100 TO 107 DEGREE RANGE
THIS AFTERNOON.
THE FRONTAL BOUNDARY IS NEAR THE RED RIVER AND IN SW ARK. THIS
BOUNDARY WILL MOVE SOUTHWEST INTO NE PORTIONS OF SE TEXAS LATE
TONIGHT/EARLY FRIDAY MORNING. BEHIND THE BOUNDARY WE WILL SEE A
DRIER AIRMASS ADVECT INTO THE REGION. THE LOCATION OF BOUNDARY WILL
DETERMINE WHERE THE BEST RAIN CHCS ARE TOMORROW. SOUTH OF THE
BOUNDARY EXPECT SCT CONVECTION AGAIN WHERE PW VALUES ARE JUST
OVER 2 INCHES. WILL TAPER POPS UPWARD FROM THE NE TO SW AREAS OF
SE TX....BASED ON THE PRECIPITABLE WATER GRADIENT EXPECTATIONS
ON FRI. BY SAT MORNING THE DEEP MOISTURE WILL BE OFFSHORE AND SW
OF SE TX...SO RAIN CHCS WILL BE VERY SMALL AGAIN FROM SAT
THROUGH MID-WEEK.
NOT MUCH CHG EXPECTED IN MAX TEMPS...SOME VARIATIONS THE NEXT
COUPLE OF DAYS DUE TO DIFFERENCES IN LAYER MOISTURE LEVELS. FAR
INLAND AREAS ON SAT COULD SEE WIDESPREAD TEMPS OVR 100 DUE TO THE
VERY DRY AIRMASS THAT WILL BE IN PLACE.
MARINE...A WEAK BACKDOOR FRONT NORTH OF THE AREA WILL EFFECT THE
COAST LATE THURSDAY INTO FRIDAY. HOWEVER...THE WINDS ASSOCIATED
WITH THE FRONT SHOULD BE LIGHT ENOUGH TO BE INFLUENCED BY THE SEA
BREEZE ON FRIDAY THROUGH THE WEEKEND.
AN OFFSHORE FLOW DURING THE EARLY MORNING HOURS WILL RELAX AND
BECOME ONSHORE DURING PEAK HEATING IN THE AFTERNOON BEFORE BECOMING
SOUTHWESTERLY IN THE EVENING. RAIN CHANCES WILL BE ON THE INCREASE
TONIGHT AND FRIDAY AS POOL OF MOISTURE OVER LA AND GULF SLIDES
WESTWARD INTO THE UPPER TEXAS COASTAL WATERS.
FORECAST MODELS BUILD THE HIGH PRESSURE RIDGE BACK OVER THE COASTAL
WATERS LATE IN THE WEEKEND AND EARLY NEXT WEEK. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 99 75 101 76 / 20 30 20 10 10
HOUSTON (IAH) 79 99 77 100 76 / 30 30 10 10 10
GALVESTON (GLS) 82 92 82 94 82 / 30 30 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...99
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
625 PM CDT THU JUL 30 2015
.AVIATION...
/00Z TAFS/
VFR CONDITIONS ARE EXPECTED ACROSS AREA SITES THROUGH FRIDAY
AFTERNOON. WINDS WILL BE FROM THE EAST AND SOUTHEAST 5 TO 10 KNOTS
THIS EVENING...BECOMING LIGHT AND VARIABLE OVERNIGHT AND PICKING
BACK UP TO 10 KNOTS FRIDAY AFTERNOON WITH HIGHER GUSTS MAINLY
ACROSS THE RIO GRANDE PLAINS. A SURGE OF LOW TO MID LEVEL MOISTURE
IS FORECAST TO PUSH ACROSS THE EASTERN HALF OF SOUTH CENTRAL TEXAS
FRIDAY AFTERNOON AND EVENING. A FEW SHOWERS AND EVEN AN ISOLATED
THUNDERSTORM COULD POP ALONG THE I-35 SITES MID/LATE FRIDAY
AFTERNOON. THIS ACTIVITY SHOULD COME TO AN END SHORTLY AFTER
SUNSET.
&&
.PREV DISCUSSION... /ISSUED 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...17
SYNOPTIC/GRIDS...RUNYEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
623 PM CDT THU JUL 30 2015
.DISCUSSION...
SEE 00Z AVIATION DISCUSSION.
&&
.AVIATION...
SHRA/TSRA APPROACHING KCXO/KIAH AND WILL LIKELY IMPACT THESE TAF
SITS FOR THE NEXT HOUR OR SO. COULD GET SOME BRIEF GUSTY WINDS
WITH THESE STORMS. FELT THE RAP HAS VERIFIED BEST FROM YESTERDAY
AND WILL LEAN TOWARD THE RAP/GFS FOR TONIGHT AND FRIDAY. FEEL
SHRA/TSRA WILL END BETWEEN 02-03Z WITH ONLY ISOLATED SHRA
THEREAFTER. THE RAP BEGINS TO BRINGS THINGS BACK UP AROUND 12Z SO
WILL RESTART VCSH BETWEEN 11-13Z AREAWIDE. DRY AIR WILL FILTER
INTO THE AREA FROM THE NE ON FRIDAY AND WILL END PRECIP FROM NE TO
SW DURING THE AFTN. NUMEROUS OUTFLOW BOUNDARIES AND A WEAK
PRESSURE GRADIENT MAKES FCSTING WIND DIRECTION DIFFICULT. 43
&&
.PREV DISCUSSION... /ISSUED 304 PM CDT THU JUL 30 2015/
DISCUSSION...
SCT CONVECTION IS OCCURRING ACROSS NORTHERN AND EASTERN AREAS THIS
AFTERNOON. THIS ACTIVITY IS MOVING SOUTHWEST...SO CENTRAL AREAS
WILL LIKELY SEE SCT CONVECTION AS WELL LATER THIS AFTERNOON AND
EVENING. NORTHERN AND EASTERN AREAS ARE MOIST AND UNSTABLE...SO
ISOLATED STRONG STORMS ARE POSSIBLE. MAX TEMPS ARE AROUND 100
ACROSS FAR INLAND AREAS...UPPER 90S CENTRAL AREAS...AND LOWER TO
MID 90S COAST. HEAT INDICES REMAIN IN THE 100 TO 107 DEGREE RANGE
THIS AFTERNOON.
THE FRONTAL BOUNDARY IS NEAR THE RED RIVER AND IN SW ARK. THIS
BOUNDARY WILL MOVE SOUTHWEST INTO NE PORTIONS OF SE TEXAS LATE
TONIGHT/EARLY FRIDAY MORNING. BEHIND THE BOUNDARY WE WILL SEE A
DRIER AIRMASS ADVECT INTO THE REGION. THE LOCATION OF BOUNDARY WILL
DETERMINE WHERE THE BEST RAIN CHCS ARE TOMORROW. SOUTH OF THE
BOUNDARY EXPECT SCT CONVECTION AGAIN WHERE PW VALUES ARE JUST
OVER 2 INCHES. WILL TAPER POPS UPWARD FROM THE NE TO SW AREAS OF
SE TX....BASED ON THE PRECIPITABLE WATER GRADIENT EXPECTATIONS
ON FRI. BY SAT MORNING THE DEEP MOISTURE WILL BE OFFSHORE AND SW
OF SE TX...SO RAIN CHCS WILL BE VERY SMALL AGAIN FROM SAT
THROUGH MID-WEEK.
NOT MUCH CHG EXPECTED IN MAX TEMPS...SOME VARIATIONS THE NEXT
COUPLE OF DAYS DUE TO DIFFERENCES IN LAYER MOISTURE LEVELS. FAR
INLAND AREAS ON SAT COULD SEE WIDESPREAD TEMPS OVR 100 DUE TO THE
VERY DRY AIRMASS THAT WILL BE IN PLACE.
MARINE...A WEAK BACKDOOR FRONT NORTH OF THE AREA WILL EFFECT THE
COAST LATE THURSDAY INTO FRIDAY. HOWEVER...THE WINDS ASSOCIATED
WITH THE FRONT SHOULD BE LIGHT ENOUGH TO BE INFLUENCED BY THE SEA
BREEZE ON FRIDAY THROUGH THE WEEKEND.
AN OFFSHORE FLOW DURING THE EARLY MORNING HOURS WILL RELAX AND
BECOME ONSHORE DURING PEAK HEATING IN THE AFTERNOON BEFORE BECOMING
SOUTHWESTERLY IN THE EVENING. RAIN CHANCES WILL BE ON THE INCREASE
TONIGHT AND FRIDAY AS POOL OF MOISTURE OVER LA AND GULF SLIDES
WESTWARD INTO THE UPPER TEXAS COASTAL WATERS.
FORECAST MODELS BUILD THE HIGH PRESSURE RIDGE BACK OVER THE COASTAL
WATERS LATE IN THE WEEKEND AND EARLY NEXT WEEK. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 99 75 101 76 / 20 30 20 10 10
HOUSTON (IAH) 79 99 77 100 76 / 40 30 10 10 10
GALVESTON (GLS) 82 92 82 94 82 / 20 30 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...46
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
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
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
44
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
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 / 0 10 0 10
CARLSBAD NM 70 97 69 96 / 10 10 0 0
DRYDEN TX 75 100 74 99 / 0 0 0 0
FORT STOCKTON TX 72 98 73 97 / 0 0 0 0
GUADALUPE PASS TX 68 89 68 88 / 20 10 10 10
HOBBS NM 70 95 70 93 / 0 10 10 10
MARFA TX 59 90 57 88 / 20 10 0 10
MIDLAND INTL AIRPORT TX 73 98 72 97 / 0 0 0 10
ODESSA TX 73 98 74 97 / 0 0 0 0
WINK TX 75 103 73 101 / 0 0 0 0
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
80/33
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
743 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 /00Z FRIDAY THROUGH TUESDAY/...
AS OF 740 PM EDT THURSDAY...
A COLD FRONT WILL CONTINUE TO MOVE EAST ACROSS THE REGION THIS
EVENING. ISOLATED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ALONG
THE FRONT. RADAR SHOWED A STORM UPSTREAM OF KDAN AND AT CURRENT
SPEED AND DIRECTION...THIS FEATURE WILL REACH THE AIRPORT AROUND
01Z. NO CHANCE OF SHOWERS AND THUNDERSTORMS FOR THE OTHER LOCAL
TAF SITES...WHICH WERE BEHIND THE FRONT.
WITH DRIER AIR WORKING IN TONIGHT AND SURFACE DEW POINTS LOWERING
INTO THE LOWER 50S TO LOWER 60S...THE FOG THREAT SHOULD BE
MINIMIZED...THOUGH THERE IS A SMALL CHANCE THAT LWB/BCB COULD FOG
IN GIVEN SOME SLIGHTLY COOLER AIR OVER THE NEW AND GREENBRIER
RIVERS.
VFR CONDITIONS EXPECTED FRIDAY. 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...AMS/KK
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
659 PM CDT THU JUL 30 2015
UPDATED AVIATION PORTION FOR 00Z TAF 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 00Z TAF ISSUANCE
ISSUED AT 659 PM CDT THU JUL 30 2015
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS...ASSOCIATED WITH AN
UPPER LEVEL SHORT WAVE MOVING ACROSS NORTHERN WISCONSIN...WERE
DIMINISHING AS SUNSET APPROACHED. ACTIVITY SHOULD DIE OFF OR EXIT
THE AREA BY 01Z TO 02Z. WINDS WILL DECREASE WITH LOSS OF DAYTIME
HEATING AND VFR CONDITIONS SHOULD PREVAIL THROUGHOUT THE NIGHT.
BUFKIT OVERVIEW OF THE 18Z NAM AND 18Z GFS SHOWED MOISTURE IN A
LAYER FROM ABOUT 4000FT TO 6000FT...SO HAVE SOME SCATTERED TO
BROKEN CLOUDS FORECAST IN THAT HEIGHT RANGE DURING THE DAY.
SHOWERS CANNOT BE COMPLETELY RULED OUT BUT ODDS OF THEM IMPACTING
ANY PARTICULAR TAF SITE APPEAR LOW AT THIS TIME.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....ALLEN
LONG TERM......SKOWRONSKI
AVIATION.......MG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1137 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 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1137 PM CDT TUE JUL 28 2015
THE FRONT HAS ALREADY PASSED THROUGH KRST THIS EVENING AND WILL
HAVE GONE THROUGH KLSE BY 06Z. SHOWERS COMING NORTHEAST OUT OF
CENTRAL IOWA SHOULD CONTINUE TO MOVE NORTHEAST WITH THE 29.02Z
HRRR-CR SHOWING THESE MISSING KLSE WELL TO THE SOUTHEAST...SO DO
NOT PLAN TO INCLUDE ANY MENTION OF SHOWERS OR STORMS IN EITHER
TAF. STILL EXPECTING A BREEZY DAY WEDNESDAY ONCE THE INVERSION
MIXES OUT WITH WEST WINDS GUSTING INTO THE 25 TO 30 KNOT RANGE
FOR THE LATE MORNING THROUGH THE AFTERNOON. LOOKS LIKE THESE WINDS
SHOULD SETTLE DOWN EARLY WEDNESDAY EVENING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
246 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 245 AM MDT FRI JUL 31 2015
THE BROAD UPPER HIGH WILL CONTINUE TO SHIFT FURTHER WEST AND
NORTH ACROSS THE GREAT BASIN TODAY. THIS WILL ALLOW SOME
ADDITIONAL MOISTURE TO ALSO SEEP INTO COLORADO WHERE INTEGRATED PW
VALUES HAVE ALREADY INCREASED AROUND A THIRD OF AN INCH IN THE
PAST 12 HOURS OVER THE FRONT RANGE. STILL THOUGH MID LEVEL
INVERSION AROUND 500MB WILL LIMIT CONVECTION THROUGH THIS
AFTERNOON. NAM SEEMS THE MOST BULLISH ON MOISTURE AND STORM
POTENTIAL WHILE THE THE RAP IS THE DRIEST. EXPECT MAJORITY OF
STORMS WILL BE OVER EAST SLOPES AND HIGHER TERRAIN. SOME OF THIS
MAY SPILL OUT OVER THE ADJACENT PLAINS BY LATER THIS AFTERNOON.
NOT MUCH HELP UPSTAIRS AS QG FIELDS SHOWING SOME SUBSIDENCE IN THE
700MB LAYERS AND NEUTRAL FORCING ALOFT. ISOLATED POPS ON THE
PLAINS WITH HIGHER SCATTERED CHANCES IN THE MOUNTAINS SHOULD
SUFFICE. EXPECT TEMPERATURES WILL BE SIMILAR TO THURSDAY READINGS.
CONVECTION WILL DIMINISH DURING THE EVENING HOURS WITH LACK OF ANY
UPPER AIR SUPPORT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 207 AM MDT FRI JUL 31 2015
BY SATURDAY MORNING...A NEGATIVELY TILTED UPPER RIDGE IS STILL OVER
THE WRN CONUS WITH THE 500MB HIGH OVER SERN NEW MEX. AT THE SFC...
BROAD CLOCKWISE CIRCULATION AROUND A STG HIGH IN NWRN ARKANSAS
CONTINUES TO ADVECT INCREASING AMOUNTS OF LOW-LEVEL MOISTURE
NORTHWARD ALONG THE COLORADO/KANSAS BORDER. MEANWHILE THE MID-LEVEL
NWLY FLOW CONTINUES TO DRY ON THE SOUTH SIDE OF AN 80-90KT JET
SEGMENT. BY LATE AFTERNOON...MODELS SHOW A NEARLY NEUTRAL TILT UPPER
RIDGE MIGRATING EASTWARD OVER ERN UTAH/COLORADO CAUSING THE MID-
LEVEL FLOW OVER THE FCST AREA TO BECOME N-NWLY. AT THE SAME TIME
SELY BNDRY LAYER FLOW EAST OF THE MTNS CONTINUES TO TRANSPORT LOW
LEVEL MOISTURE UP INTO THE FCST AREA. MODELS SHOW MEAN LAYER PW
VALUES PUSHING AN INCH ACRS SERN SECTIONS OF THE CWA BY EVENING.
HOWEVER...MOISTURE APPEARS RELATIVELY SHALLOW...CAPPED BY A MUCH
DRIER N-NWLY FLOW ABOVE 650 MBS. OVERNIGHT SELY SFC WINDS ON THE
PLAINS TURN SWLY WHICH FLUSHES OUT SOME OF THE MOISTURE UP ALONG
THE FRONT RANGE.
DRY OUT IS SHORT-LIVED AS THE GFS...SREF AND NAM SHOW A RETURN TO A
MOIST SELY FLOW DURING THE DAY SUNDAY. MODELS SHOW MEAN LAYER PW
VALUES APPROACH 1.25 INCH OVER NRN PORTIONS OF THE I-25 URBAN
CORRIDOR BY LATE AFTERNOON. THIS TIME THE MOISTURE LAYER APPEARS
DEEPER AND WITH LIGHT/VARIABLE TRANSPORT WINDS SLOW STORM MOTIONS
WOULD CONCEIVABLY RESULT IN LOCALLY HEAVY RAINFALL. ALTHOUGH QPF
FIELDS DO NOT INDICATE ANYTHING LIKE THAT HAPPENING APPARENTLY DUE
TO A LACK OF CAPE AND SOME KIND OF FORCING MECHANISM SUCH AS A
FRONTAL BNDRY OR DEEP UPSLOPE FLOW. HOWEVER MODELS INDICATE CAPES IN
THE 1000-1500 J/KG RANGE...AND ON THE NAM AS HIGH AS 2000 J/KG...AND
DECENT LOW-LEVEL CONVERGENCE/SHEAR ALONG THE PALMER DIVIDE. ITS MORE
LIKELY HERE THAT A FEW SUPERCELLS CAPABLE OF HEAVY RAINFALL...HAIL
AND STG GUSTY WINDS WILL FORM AND TRACK EAST-SOUTHEAST ALONG THE
DIVIDE DURING THE LATE AFTERNOON AND EVENING HRS ON SUN. THE SRN
FRONT RANGE FOOTHILLS AND SOUTH PARK IS ANOTHER AREA WHERE THERE`S
AN ELEVATED POTENTIAL FOR T-STORMS AT THIS TIME DUE TO THIS MOIST
AND UNSTABLE SELY FLOW. ACTUALLY THERE`S A GREATER POTENTIAL FOR
STORMS PRODUCING HEAVY RAINFALL IN PARK COUNTY WITH THIS SET UP.
BY SUNDAY NIGHT...THE NAM...GFS AND ECMWF ALL NOW SHOW A MID-LEVEL
SHORTWAVE TROUGH LIFTING NEWRD ACRS THE STATE WITH THE UPPER RIDGE
COLLAPSING AS IT CONTINUES TO SHIFT EAST. WAVE IS FCST TO REACH THE
FRONT RANGE URBAN CORRIDOR BY EARLY MONDAY MORNING. ITS PASSAGE
COULD ENHANCE OR EXTEND SHOWER/T-STORM DEVELOPMENT IN THE HIGH
COUNTRY THROUGH THE LATE EVENING HRS. NOT SURE THIS DISTURBANCE WILL
HAVE MUCH OF AN IMPACT ON AREAS EAST OF THE MTNS OVERNIGHT.
ON MONDAY...MOISTURE...INSTABILITY AND MODEST QG LIFT ASSOCIATED
WITH THE PASSING SHORTWAVE EXPECTED TO PRODUCE MORE CLOUD COVER AND
A SLIGHTLY GREATER CHANCE OF SHOWERS/T-STORMS FOR THE ENTIRE FCST
AREA. MOST MODELS SHOW THIS FEATURE EXITING THE STATE BY EVENING
WITH DRYING AND STABILIZATION IN ITS WAKE AS THE UPPER RIDGE AXIS
MOVES OVERHEAD OVERNIGHT.
TUESDAY SHOULD BE A DRIER AND SLIGHTLY WARMER DAY WITH ANY STORM
DEVELOPMENT RELEGATED TO THE HIGH COUNTRY. ON WEDNESDAY... TEMPS
CONTINUE TO WARM BOTH SFC AND ALOFT...AND HUMIDITIES LOWER WITH
THE UPPER RIDGE AMPLIFYING OVER THE CENTRAL ROCKIES. HOWEVER STILL
CANNOT RULE OUT A FEW LATE DAY GUSTY T-STORMS IN THE HIGH COUNTRY.
BY THURSDAY...MEDIUM RANGE MODELS SHOW THE UPPER RIDGE MOVING OVER
THE GREAT PLAINS PLACING COLORADO UNDER SWLY FLOW ALOFT. COULD SEE
SUBTROPICAL MOISTURE CARRIED NORTH BY THIS FLOW IN TANDEM WITH A
SHORTWAVE TROUGH THAT MODELS SHOW SWINGING OUT OF THE 4-CORNERS
REGION LATE IN THE DAY. AS A RESULT COULD SEE A MODEST INCREASE IN T-
STORM CHANCES MAINLY FOR THE HIGH COUNTRY. OTHERWISE THURSDAY TEMPS
LITTLE CHANGED FROM THE DAY BEFORE.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 207 AM MDT FRI JUL 31 2015
SURFACE TROF OVER DENVER WITH HEALTHY S-SW WINDS OVER DEN/APA AND
NW WINDS AT BJC. WINDS EXPECTED TO TURN SOUTHEAST OVER ENTIRE AREA
THIS AFTERNOON. MOISTURE LEVELS A BIT HIGHER TODAY AND EXPECT
ISOLATED COVERAGE OF STORMS BY LATER THIS AFTERNOON. HOWEVER AREAL
COVERAGE TOO LOW TO MENTION IN TERMINAL FORECASTS FOR NOW. EXPECT
BRIEF RAIN AND GUSTY WINDS WITH ANY POTENTIAL SHOWERS IN THE
AREA.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1129 PM CDT THU JUL 30 2015
.UPDATE...
ISSUED AT 1126 PM CDT THU JUL 30 2015
HAVE ADDED ISOLATED STORM WORDING FAR SW SECTIONS EARLY FRI
MORNING FOR A FEW HOURS. CONVECTION CONTINUES TO CYCLE ACROSS ERN
NE AND JUST WILL NOT GO AWAY. LATEST SPC MESOANALYSIS SHOWS 1-2K
J/KG MUCAPES WITH LESS THAN 50 J/KG CINHS IN ZONE OF INCREASING
H85/H7 THETA-E ADVECTION. SEEMS TO BE SOME KINEMATIC CONTRIBUTION
AS WELL DUE TO LIFT WELL AHEAD OF FAR NRN ND/MN SHORT WAVE NOTED
IN WATER VAPOR IMAGERY. STORMS COULD JUST TOUCH STRONG LIMITS AT
TIMES WITH 30KTS OF EFFECTIVE SHEAR AND DECENT DCAPES.
&&
.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...31/06Z
ISSUED AT 1126 PM CDT THU JUL 30 2015
UNLESS CONDITIONS CHANGE SOON...EXPECT VFR CONDITIONS ACROSS TAFS
AND NO THUNDER WITH ERN NE CONVECTION STAYING SW OF SITES.
CONVECTION SEEMS TO HAVE CYCLED DOWN AND THEN BACK OUT OF NOWHERE
RECENTLY HOWEVER...SO CONFIDENCE IN THAT HAS DECREASED SOMEWHAT.
OTHERWISE EXPECT NOTHING MORE THAN SCT MID CLOUDS AND GENERALLY
LIGHT WINDS EVENTUALLY VEERING TO NWLY DURING FRI PEAK HEATING
MIXING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...FAB
LONG TERM...KOTENBERG
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
235 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
UPPER RIDGE OVER THE GREAT BASIN WILL GRADUALLY BUILD OVER THE
CENTRAL ROCKIES AND BE THE DOMINANT FEATURE OF THE SHORT TERM
PERIOD. AS A RESULT...PRECIPITATION CHANCES WILL BE RATHER LOW AND
TEMPERATURES WILL BE WARMING. THAT BEING SAID...MAY SEE AN ISOLATED
STORM OR TWO THIS AFTERNOON IN NORTHEAST COLORADO AS HINTED AT BY
THE HRRR NEAR A WEAK SURFACE CONVERGENCE LINE. ENVIRONMENT WILL
BE SIMILAR TO YESTERDAY SO CANT TOTALLY RULE OUT A SEVERE STORM
CAPABLE OF PRODUCING STRONG WINDS...BUT THINK COVERAGE WILL BE
VERY LIMITED DUE TO LACK OF UPPER SUPPORT. SOME OF THE HIRES NAM
MEMBERS PAINT A SIMILAR SCENARIO SATURDAY AFTERNOON IN NORTHEAST
COLORADO SO CARRIED SOME LOW POPS. ONCE AGAIN SEVERE PARAMETERS
ARE FAIRLY DECENT SHOULD SOMETHING DEVELOP. PERHAPS THE NEXT BEST
CHANCE FOR THUNDERSTORMS WILL BE SUNDAY AFTERNOON AND EVENING WITH
SOMEWHAT BETTER LOOKING TROUGH COMING OUT OF COLORADO AND TOPPING
THE RIDGE AXIS IN THE CENTRAL PLAINS. HOWEVER NOT ENOUGH
CONFIDENCE AT THIS POINT WITH THE STRONG RIDGE IN PLACE THAT IT
WILL ACTUALLY PLAY OUT THAT WAY SO WILL ONLY CARRY SILENT 10 POPS
OR LESS.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM MDT THU JUL 30 2015
VFR CONDITIONS ARE EXPECTED FOR BOTH TERMINALS THROUGH THE
DURATION OF THE TAF PERIOD. AN UPPER LEVEL HIGH PRESSURE SYSTEM
WILL BRING DRY CONDITIONS WITH LIMITED CLOUD COVER...AS WELL AS
LIGHT SOUTHERLY WINDS TO BOTH KGLD AND KMCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...024
LONG TERM...JBH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1125 PM MDT THU JUL 30 2015
.UPDATE...
ISSUED AT 743 PM MDT THU JUL 30 2015
THUNDERSTORMS IN EASTERN COLORADO ARE FOLLOWING A SOUTHWARD
TRAJECTORY WITH THE CLOUD COVER MOVING MORE TO THE EAST/SOUTHEAST.
MODELS INDICATE STORMS SHOULD HAVE ENDED...BUT STORMS CONTINUE TO
MOVE ALONG 500 MB SHORTWAVE TROUGH JUST EAST OF THE 12 C 700 MB
ISOTHERM. AT THE CURRENT SPEED...STRONGER STORMS SHOULD MOVE OUT
OF THE FORECAST AREA BY MIDNIGHT MDT. SLIGHT CHANCES FOR SOME
PRECIPITATION WILL LINGER A LITTLE AFTER MIDNIGHT MDT AS THE SMALL
SHORTWAVE MOVES THROUGH THE HIGH PLAINS.
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 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM MDT THU JUL 30 2015
VFR CONDITIONS ARE EXPECTED FOR BOTH TERMINALS THROUGH THE
DURATION OF THE TAF PERIOD. AN UPPER LEVEL HIGH PRESSURE SYSTEM
WILL BRING DRY CONDITIONS WITH LIMITED CLOUD COVER...AS WELL AS
LIGHT SOUTHERLY WINDS TO BOTH KGLD AND KMCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...MK
SHORT TERM...DR
LONG TERM...JN
AVIATION...MK
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1143 PM MDT THU JUL 30 2015
.AVIATION...
06Z TAF CYCLE
SHRA/TSRA CONTINUE ACROSS MUCH OF THE EASTERN PLAINS AND PORTIONS
OF NW NM. THE FORMER IS MOVING TOWARD THE N AND NE AND THE LATTER
IS MOVING TOWARD THE W AND NW. THE ACTIVITY ACROSS THE NW SHOULD
CONTINUE FOR ANOTHER COUPLE OF HOURS...BUT LIKE LAST NIGHT...THE
ACTIVITY ACROSS THE EAST MAY PERSIST THROUGH SUNRISE. MVFR
CIGS/VSBYS WILL BE POSSIBLE WITH THE STRONGEST ACTIVITY. SHOULD
STORMS DIMINISH EARLIER...COULD SEE MVFR/IFR CIGS ACROSS PORTIONS
OF THE NE PLAINS. ANOTHER ROUND OF SHRA/TSRA IS EXPECTED ON
FRIDAY FAVORING THE HIGH TERRAIN AND PORTIONS OF NE NM. STEERING
FLOW WILL BE LIGHT...PERHAPS LIGHTER THAN TODAY AS THE UPPER HIGH
REMAINS OVERHEAD. MVFR CIGS AND BRIEF MT OBSCURATIONS WILL BE
POSSIBLE FRI AFTN.
34
&&
.PREV DISCUSSION...906 PM MDT THU JUL 30 2015...
.UPDATE...
UPDATED POP/WEATHER GROUPINGS IN THE GRIDDED FORECAST FOR REST OF
TONIGHT. ALSO UPDATED THE FLASH FLOOD WATCH BY ELIMINATING
WESTERN/CENTRAL AREAS. LATEST RADAR/SATELLITE IMAGERY AND TO A
CERTAIN DEGREE MODELING SHOWS THE MAIN THREAT FOR HEAVY RAIN
ACROSS EASTERN AREAS. THUS LEFT THE WATCH UP THERE. MODELS SEEM TO
BE OVERDOING CONDITIONS ACROSS WESTERN/CENTRAL AREAS DESPITE SOME
FOCUSING WAVE FEATURES. THE LATEST HRRR HAS BACK OFF QPF NUMBERS
ACROSS SW/WC HIGHLANDS ALTHOUGH THERE IS A WAVE POISED TO IMPACT
THOSE AREAS TONIGHT. SUSPECT THE RAINFALL WILL BE MORE STRATIFORM
WITH LESS OF A HEAVY RAIN THREAT. SIMILARLY FOR NW AREAS WHERE
THERE IS SOME ONGOING RAINFALL WITHIN A MID LEVEL DEFORMATION
AREA. VERY MOIST ENVIRONMENT SO IT DOESNT TAKE MUCH TO PRODUCE A
RAIN SHOWER.
50
&&
.PREV DISCUSSION...240 PM MDT THU JUL 30 2015...
.SYNOPSIS...
SHOWERS AND STORMS WITH LOCALLY HEAVY RAINFALL WILL CONTINUE TO
IMPACT NEW MEXICO THROUGH THE WEEKEND. THE FLASH FLOOD POTENTIAL
WILL REMAIN ELEVATED AS SLOW-MOVING STORMS DROP A QUICK 1 TO 2
INCHES OF RAIN. AREAS OF STEEP TERRAIN...BURNED FORESTS...URBAN
DRAINAGES...AND AREAS THAT PICK UP DAILY ROUNDS OF HEAVY RAIN WILL
BE THE MOST SUSCEPTIBLE. A VERY SLOW DRYING AND WARMING TREND IS
EXPECTED BEGINNING NEXT WEEK.
&&
.DISCUSSION...
THE CLIMATOLOGICAL PEAK FOR DEEP ATMOSPHERIC MOISTURE AND FLASH
FLOOD POTENTIAL IS CERTAINLY DELIVERING AS WE NEAR THE END OF JULY
2015. A REMNANT CONVECTIVE VORTEX FROM LAST NIGHT MOVING SLOWLY
NORTH ALONG THE CONT DVD IS FOCUSING REDEVELOPMENT TODAY. ANOTHER
AREA OF MOISTURE CONVERGENCE IS FIRING UP FROM LINCOLN COUNTY NORTH
INTO TORRANCE COUNTY WHERE RADAR-BASED STORM TOTAL ACCUMULATION IS
ALREADY NEAR 3 INCHES IN SOME LOCALES. THE WEAKEST STEERING FLOW
IS FOCUSED OVER NORTHERN NM WHERE DEFORMATION STRETCHES FROM WEST
TO EAST OVER THE HIGH TERRAIN. ANY ACTIVITY THERE WILL BE NEARLY
STATIONARY AND PRODUCE TORRENTIAL RAINFALL. ALL THESE AREAS ARE
UNDER THE FLASH FLOOD WATCH AND NO CHANGES WILL BE MADE. SOME
MINOR RIVER FLOODING IS ALSO POSSIBLE ALONG TRIBUTARIES TO MAIN
STEM RIVERS SUCH AS THE RIO GRANDE AND PECOS THROUGH THE WEEKEND.
EXPECT LITTLE TO NO CHANGE FRIDAY...EXCEPT PERHAPS A GREATER FOCUS
FOR HEAVY RAINFALL FARTHER NORTHWEST TOWARD THE FOUR CORNERS. THIS
WEEKEND WILL SEE ELEVATED FLASH FLOOD POTENTIAL AS THE UPPER HIGH
ESTABLISHES FIRMLY OVERHEAD. EACH AFTERNOON OF HEAVY RAINFALL IN
THE SAME AREAS WILL EXACERBATE FLASH FLOOD POTENTIAL.
A SLOW WARMING AND DRYING TREND IS STILL EXPECTED AS WE HEAD INTO
EARLY NEXT WEEK WITH NO ADDITIONAL INFLUX OF MOISTURE NOTED. THE
RECYCLING PROCESS WILL BE THE DOMINANT PLAYER...WHICH WILL BE VERY
EFFICIENT. NASA SPORT LIS SHOWS MOIST SOILS ARE EXPANDING OVER A
LARGER AREA OF NM AND TO DEEPER LAYERS. OVERALL...CONDITIONS ARE
LOOKING VERY TYPICAL OF A MATURE MONSOON PATTERN THROUGH EARLY
AUGUST.
GUYER
&&
.FIRE WEATHER...
UPPER HIGH CENTER ATTEMPTING TO BECOME ESTABLISHED OVER NEW MEXICO
THIS AFTERNOON...AND MODELS PERSIST ON IT LINGERING OVER THE STATE
FOR MUCH OF THE UPCOMING WEEK...ALTHOUGH IT/S LIKELY TO WOBBLE
AROUND A BIT. MOISTURE TO REMAIN TRAPPED UNDER THE RIDGE...BUT
SHOULD VERY SLOWLY WARM AND DRY NEXT WEEK. CELL MOTION COULD BE
SOMEWHAT ERRATIC FOR THE REST OF THIS AFTERNOON AND TONIGHT...BUT
GENERALLY NORTHWEST AND NORTH WEST OF THE RGV AND NORTH TO NORTHEAST
EAST OF THE RGV. MOVEMENT AND SPEED WILL TREND TO SLOWER AND MORE
ERRATIC FRIDAY AND INTO THE WEEKEND WITH THE HIGH CENTER OVERHEAD.
THEREFORE...LOCALLY HEAVY RAINFALL WILL BE POSSIBLE AT LEAST THROUGH
FRIDAY.
HIGH TEMPERATURES TO VARY FROM MOSTLY BELOW AVERAGE THROUGH SUNDAY
TO NEAR TO ABOVE AVERAGE NEXT MONDAY THROUGH THURSDAY. WHILE MIN RH
VALUES WILL TREND DOWNWARD NEXT WEEK...OVERNIGHT RECOVERIES FORECAST
TO REMAIN EXCELLENT.
VENT RATES OVER PORTIONS OF THE NORTH WILL BE FAIR TO POOR THROUGH
SUNDAY. POOR RATES ARE FORECAST FOR THE NORTHEAST AND SOUTHWEST
MONDAY.
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 4 AM MDT FRIDAY FOR THE FOLLOWING ZONES...
NMZ512>515-523-527>537.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
309 AM CDT FRI JUL 31 2015
.DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 71 91 71 / 20 10 10 20
HOBART OK 94 71 89 70 / 20 30 30 20
WICHITA FALLS TX 96 74 96 73 / 20 20 20 20
GAGE OK 88 68 86 67 / 20 20 20 30
PONCA CITY OK 91 71 91 72 / 20 10 10 20
DURANT OK 96 73 97 73 / 20 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
84/17
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1249 AM CDT FRI JUL 31 2015
.AVIATION...
VFR CONDITIONS SHOULD PREVAIL FOR MOST OF THE PERIOD. DEEP
MOISTURE IS ON THE INCREASE AS A WEAK DISTURBANCE MOVES IN FROM
THE EAST. THIS FEATURE WILL BRING SCATTERED SHOWERS AND
THUNDERSTORMS TO THE AREA THIS AFTERNOON. WILL INCLUDE THE MENTION
OF VCTS FOR THE I-35 TAF SITES. CHANCES ARE MUCH TOO LOW FOR KDRT
FOR ANY MENTION. SOME OF THE THUNDERSTORMS COULD BE HEAVY...WHICH
MAY CAUSE VISIBILITIES TO DROP TO MVFR CATEGORIES OR LOWER. GUSTY
WINDS WILL ALSO BE POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 937 PM CDT THU JUL 30 2015/
UPDATE...LEADING EDGE OF THE MOISTURE PLUME FROM THE EAST HAS
ARRIVED INTO THE FAR EASTERN CWA THIS EVENING. HOWEVER...A GRADUAL
DOWNWARD TREND IN CONVECTIVE ACTIVITY WILL TAKE PLACE THROUGH THE
REMAINDER OF THE LATE EVENING WITH LOSS OF HEATING. VERY MINOR
EDITS MADE TO HOURLY T/TD/APPARENT T GRIDS BASED ON TRENDS. NO
OTHER UPDATES PLANNED THIS EVENING. DEEPER MOISTURE CONTINUES TO
MOVE WEST AND SOUTHWEST INTO THE CWA OVERNIGHT AND FRIDAY. WITH
DE-STABILIZATION TOMORROW AFTERNOON EXPECT ISOLATED TO WIDELY
SCATTERED SHOWERS AND THUNDERSTORMS OVER THE REGION. A FEW STORMS
COULD PRODUCE STRONGER DOWNDRAFTS AND WIND GUSTS GIVEN MODEL
FORECAST SOUNDINGS...AND MENTIONED IN HWO.
PREV DISCUSSION... /ISSUED 625 PM CDT THU JUL 30 2015/
AVIATION...
/00Z TAFS/
VFR CONDITIONS ARE EXPECTED ACROSS AREA SITES THROUGH FRIDAY
AFTERNOON. WINDS WILL BE FROM THE EAST AND SOUTHEAST 5 TO 10 KNOTS
THIS EVENING...BECOMING LIGHT AND VARIABLE OVERNIGHT AND PICKING
BACK UP TO 10 KNOTS FRIDAY AFTERNOON WITH HIGHER GUSTS MAINLY
ACROSS THE RIO GRANDE PLAINS. A SURGE OF LOW TO MID LEVEL MOISTURE
IS FORECAST TO PUSH ACROSS THE EASTERN HALF OF SOUTH CENTRAL TEXAS
FRIDAY AFTERNOON AND EVENING. A FEW SHOWERS AND EVEN AN ISOLATED
THUNDERSTORM COULD POP ALONG THE I-35 SITES MID/LATE FRIDAY
AFTERNOON. THIS ACTIVITY SHOULD COME TO AN END SHORTLY AFTER
SUNSET.
PREV DISCUSSION... /ISSUED 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 99 76 / 20 20 0 10 0
AUSTIN BERGSTROM INTL AIRPORT 74 99 73 98 75 / 20 20 0 - 0
NEW BRAUNFELS MUNI AIRPORT 76 100 74 100 75 / 20 20 10 10 0
BURNET MUNI AIRPORT 75 98 74 97 75 / 20 20 - 20 -
DEL RIO INTL AIRPORT 78 101 78 101 78 / 20 20 10 10 0
GEORGETOWN MUNI AIRPORT 75 98 74 98 76 / 20 20 0 10 0
HONDO MUNI AIRPORT 76 100 75 99 74 / 20 20 10 10 0
SAN MARCOS MUNI AIRPORT 76 99 75 98 75 / 20 20 10 10 0
LA GRANGE - FAYETTE REGIONAL 76 99 75 99 76 / 20 10 10 - 0
SAN ANTONIO INTL AIRPORT 78 99 77 99 77 / 20 20 10 10 0
STINSON MUNI AIRPORT 77 100 76 100 76 / 20 20 10 - 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...HAMPSHIRE
SYNOPTIC/GRIDS...OAKS
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1134 PM CDT THU JUL 30 2015
.DISCUSSION...
SEE 06Z AVIATION DISCUSSION.
&&
.AVIATION...
PRECIPITATION LASTED A BIT LONGER THAN EXPECTED BUT IS IN THE
PROCESS OF DISSIPATING. AN ISOLATED SHOWER CAN NOT BE RULED OUT AT
ANY TIME OVERNIGHT AS PW VALUES REMAIN ABOVE 2.00 INCHES. NAM12
AND THE GFS DIFFER WITH PW VALUES ON FRIDAY WITH THE NAM MORE
AGGRESSIVE WITH MOISTURE. THE RAP HAS BACKED OFF SIGNIFICANTLY
WITH MORNING PRECIP AND IS NOW WAITING ON HEATING TO TRIGGER
SHRA/TSRA. WILL LEAN TOWARD A RAP/HRRR/GFS BLEND WHICH FOCUSES
MUCH OF THE PRECIP ON FRI OVER THE SW HALF OF THE CWA. WILL CARRY
VCSH FOR KLBX...KSGR...KHOU AND KGLS. DRY AIR WILL FILTER INTO
THE AREA FROM THE NE LATE FRIDAY AFTN AND WILL END PRECIP FROM NE
TO SW TOWARD EVENING. NUMEROUS OUTFLOW BOUNDARIES AND A WEAK
PRESSURE GRADIENT MAKES FCSTING WIND DIRECTION DIFFICULT. 43
&&
.PREV DISCUSSION... /ISSUED 912 PM CDT THU JUL 30 2015/
DISCUSSION...
SHOWERS AND THUNDERSTORMS STILL DRIFTING DOWN INTO NE ZONES AT
THIS HOUR. ANOTHER IMPORTANT FEATURE...RADAR SHOWING OUTFLOW FROM
LOUISIANA CONVECTION MOVING IN FROM THE EAST. THIS OUTFLOW TO
BRING SOME GUSTY EAST AND NORTHEAST WINDS SHORTLY TO GALVESTON BAY
AND EASTERN COASTAL GULF WATERS. WIND GUSTS WERE AS HIGH AS 40
KNOTS OVER COASTAL LOUISIANA...LIKELY 30 KNOTS OR SO FOR SOME
AREAS NOW. HAVE ISSUED A MARINE WEATHER STATEMENT TO GIVE A HEADS
UP FOR THIS FEATURE AND ADJUSTED WIND GRIDS AS WELL.
OVERNIGHT...EXPECT A CONTINUED SLOW WEAKENING TREND IN SHOWER AND
THUNDERSTORM ACTIVITY OVER LAND...BUT CANT RULE OUT AN ISOLATED
SHOWER OR THUNDERSTORM ANYWHERE GIVEN THE AIRMASS CATEGORIZED BY
DEEPER MOISTURE. FOR COASTAL AREAS WILL LIKELY SEE SQUALL LINE
BRUSH AT LEAST OUTER WATERS...BUT OUTFLOW WILL MOVE FROM NE TO SW
ALONG THE COAST WITH SOME ADDITIONAL DEVELOPMENT POSSIBLE. HAVE
BUMPED UP POPS FOR COASTAL WATERS TO COVER THIS. HIGH RESOLUTION
RAPID REFRESH SUPPORTS THIS SCENARIO. 46
PREV DISCUSSION... /ISSUED 304 PM CDT THU JUL 30 2015/
DISCUSSION...
SCT CONVECTION IS OCCURRING ACROSS NORTHERN AND EASTERN AREAS THIS
AFTERNOON. THIS ACTIVITY IS MOVING SOUTHWEST...SO CENTRAL AREAS
WILL LIKELY SEE SCT CONVECTION AS WELL LATER THIS AFTERNOON AND
EVENING. NORTHERN AND EASTERN AREAS ARE MOIST AND UNSTABLE...SO
ISOLATED STRONG STORMS ARE POSSIBLE. MAX TEMPS ARE AROUND 100
ACROSS FAR INLAND AREAS...UPPER 90S CENTRAL AREAS...AND LOWER TO
MID 90S COAST. HEAT INDICES REMAIN IN THE 100 TO 107 DEGREE RANGE
THIS AFTERNOON.
THE FRONTAL BOUNDARY IS NEAR THE RED RIVER AND IN SW ARK. THIS
BOUNDARY WILL MOVE SOUTHWEST INTO NE PORTIONS OF SE TEXAS LATE
TONIGHT/EARLY FRIDAY MORNING. BEHIND THE BOUNDARY WE WILL SEE A
DRIER AIRMASS ADVECT INTO THE REGION. THE LOCATION OF BOUNDARY WILL
DETERMINE WHERE THE BEST RAIN CHCS ARE TOMORROW. SOUTH OF THE
BOUNDARY EXPECT SCT CONVECTION AGAIN WHERE PW VALUES ARE JUST
OVER 2 INCHES. WILL TAPER POPS UPWARD FROM THE NE TO SW AREAS OF
SE TX....BASED ON THE PRECIPITABLE WATER GRADIENT EXPECTATIONS
ON FRI. BY SAT MORNING THE DEEP MOISTURE WILL BE OFFSHORE AND SW
OF SE TX...SO RAIN CHCS WILL BE VERY SMALL AGAIN FROM SAT
THROUGH MID-WEEK.
NOT MUCH CHG EXPECTED IN MAX TEMPS...SOME VARIATIONS THE NEXT
COUPLE OF DAYS DUE TO DIFFERENCES IN LAYER MOISTURE LEVELS. FAR
INLAND AREAS ON SAT COULD SEE WIDESPREAD TEMPS OVR 100 DUE TO THE
VERY DRY AIRMASS THAT WILL BE IN PLACE.
MARINE...A WEAK BACKDOOR FRONT NORTH OF THE AREA WILL EFFECT THE
COAST LATE THURSDAY INTO FRIDAY. HOWEVER...THE WINDS ASSOCIATED
WITH THE FRONT SHOULD BE LIGHT ENOUGH TO BE INFLUENCED BY THE SEA
BREEZE ON FRIDAY THROUGH THE WEEKEND.
AN OFFSHORE FLOW DURING THE EARLY MORNING HOURS WILL RELAX AND
BECOME ONSHORE DURING PEAK HEATING IN THE AFTERNOON BEFORE BECOMING
SOUTHWESTERLY IN THE EVENING. RAIN CHANCES WILL BE ON THE INCREASE
TONIGHT AND FRIDAY AS POOL OF MOISTURE OVER LA AND GULF SLIDES
WESTWARD INTO THE UPPER TEXAS COASTAL WATERS.
FORECAST MODELS BUILD THE HIGH PRESSURE RIDGE BACK OVER THE COASTAL
WATERS LATE IN THE WEEKEND AND EARLY NEXT WEEK. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 99 75 101 76 / 20 30 20 10 10
HOUSTON (IAH) 79 99 77 100 76 / 30 30 10 10 10
GALVESTON (GLS) 82 92 82 94 82 / 30 30 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...46
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1140 PM CDT THU JUL 30 2015
UPDATED AVIATION PORTION FOR 06Z TAF 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 06Z TAF ISSUANCE
ISSUED AT 1139 PM CDT THU JUL 30 2015
EXPECT MOSTLY VFR CONDITIONS THROUGH FRIDAY EVENING. SCATTERED
SHOWERS IN CYCLONIC FLOW ACROSS NORTHEAST MINNESOTA AND WESTERN
ONTARIO COULD IMPACT FAR NORTHERN WISCONSIN BUT THINK THAT THERE
WILL BE LITTLE OR NOTHING ON THE WISCONSIN SIDE OF THE BORDER.
VFR CIGS WILL PROBABLY DEVELOP ACROSS NORTHERN WISCONSIN ALONG
WITH ISOLATED/SCATTERED SHOWERS...BUT THE ODDS OF ANY OF THE
SHOWERS IMPACTING THE TAF SITES SEEM LOW ENOUGH TO LEAVE THEM OUT
OF THE TAFS. SHOWERS AND CLOUDS SHOULD DIMINISH AROUND SUNSET ONCE
AGAIN.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....ALLEN
LONG TERM......SKOWRONSKI
AVIATION.......MG
AREA FORECAST DISCUSSION
NWS RENO NV
304 AM PDT FRI JUL 31 2015
.SYNOPSIS...
MOISTURE WILL SPREAD NORTH ACROSS THE REGION TODAY AND BRING A
CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY NEAR THE SIERRA AND IN
WESTERN NEVADA SOUTH OF HIGHWAY 50, WITH GUSTY OUTFLOW WINDS AND
LIGHTNING INDUCED FIRE STARTS POSSIBLE. THE BEST OVERALL SHOWER
AND THUNDERSTORM POTENTIAL IS EXPECTED FOR THIS WEEKEND, WITH
LOCALLY HEAVY RAINFALL AND FLOODING BECOMING THE MAIN THREATS.
&&
.SHORT TERM...
MID AND HIGH LEVEL MOISTURE CONTINUES TO SPREAD NORTH ACROSS
CALIFORNIA AND NEVADA THROUGH THE EARLY MORNING. ANOTHER WEAK
IMPULSE FARTHER SOUTH ACROSS INYO AND NYE COUNTIES IS BEING
PICKED UP BY THE LATEST NAM AND HRRR GUIDANCE, WHICH SPREAD SOME
SHOWERS ACROSS MONO, ALPINE AND SOUTHERN MINERAL COUNTIES DURING
THE EARLY AND MID MORNING.
FOR THE REMAINDER OF TODAY, FAVORED AREAS FOR AFTERNOON CONVECTION
APPEAR TO BE LIMITED TO AREAS NEAR THE SIERRA FROM MONO COUNTY
NORTHWARD TO WESTERN LASSEN COUNTY, AND IN WESTERN NV SOUTH OF
HIGHWAY 50. ELSEWHERE, THICKER CLOUD COVER SPREADING ACROSS
WESTERN NV AND NORTHEAST CA DURING THE DAY COMBINED WITH DRY EAST
FLOW NEAR THE SURFACE MAY PRODUCE CONDITIONS TOO STABLE FOR
FORMING OR SUSTAINING CONVECTION THAT MOVES NORTH OF HIGHWAY 50.
HOWEVER, OUTFLOWS FROM CELLS THAT DEVELOP NEAR THE SIERRA COULD
PUSH ACROSS WESTERN NV AND BRING A SHORT PERIOD OF STRONGER WIND
GUSTS BY LATE AFTERNOON OR EARLY EVENING. MOST ACTIVITY WILL
DIMINISH TONIGHT, ALTHOUGH A FEW BRIEF CELLS CAN`T BE RULED OUT
MAINLY SOUTH OF HIGHWAY 50 AS MOISTURE CONTINUES TO INCREASE
OVERNIGHT.
THE MAIN CONVECTIVE POTENTIAL IS EXPECTED THIS WEEKEND AS MOISTURE
CONTINUES TO SURGE NORTHWARD. WHILE CLOUD COVER COULD STILL DISRUPT
CONVECTIVE DEVELOPMENT, THERE APPEARS TO BE A LARGER WINDOW OF
HEATING ON SATURDAY, ALONG WITH RISING DEW POINTS CONTRIBUTING TO
MORE INSTABILITY. A STRONGER UPPER LEVEL DISTURBANCE IS ALSO
PROJECTED TO MOVE NORTH ACROSS THE SIERRA WITH ANOTHER DISTURBANCE
TRACKING NORTHWARD ACROSS CENTRAL NV. THESE FEATURES WOULD PROVIDE
ADDITIONAL FORCING AND INCREASE SHOWER AND THUNDERSTORM COVERAGE
WHICH MAY HOLD TOGETHER THROUGH SATURDAY NIGHT. THE CURRENT
SHORTWAVE TRACKS ARE FAVORING SOME OVERNIGHT PRECIP ACROSS THE
TAHOE BASIN AND THE RENO-CARSON CITY VICINITY, ALTHOUGH THIS COULD
VARY SINCE THE TRACK OF THESE DISTURBANCES ARE LIKELY TO CHANGE
WITH UPCOMING MODEL RUNS.
FOR SUNDAY, ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS PROBABLE
WITH VERY MOIST AND UNSTABLE CONDITIONS REMAINING. IF FULL
INSTABILITY IS REALIZED, THEN SOME STRONG STORMS WITH HEAVY RAIN
WOULD DEVELOP. HOWEVER, THERE COULD BE TOO MUCH LEFTOVER CLOUD
COVER FROM SATURDAY NIGHT`S ACTIVITY WHICH LIMITS HEATING AND
CELL STRENGTH ON SUNDAY. THIS LIMITING FACTOR IS MORE PRONOUNCED
ON THE GFS WHICH IS HOLDING MAX TEMPS DOWN TO THE MID-UPPER 80S
ACROSS WESTERN NV. WE DIDN`T MAKE MUCH CHANGE TO THE CURRENT
SUNDAY FORECAST WITH CHANCE POPS KEPT OVER MOST AREAS, SINCE
THERE IS A LOT OF UNCERTAINTY WITH THE DETAILS OF WHERE CONVECTION
EVENTUALLY OCCURS. MJD
.LONG TERM...MONDAY THROUGH THURSDAY...
THE OVERALL IDEA FOR NEXT WEEK`S FORECAST HAS NOT CHANGED, BUT DID
MAKE SOME CHANGES TO THE DETAILS. DRIER SOUTHWEST FLOW IS EXPECTED
TO BEGIN MONDAY AND CONTINUE THROUGH THE WEEK. SOME MOISTURE WILL BE
LEFT OVER MONDAY FOR SOME SHOWERS AND THUNDERSTORMS. HOWEVER, PUSHED
THE BEST CHANCES TO MONO/MINERAL WHERE THE SOUTHWEST FLOW WILL BE
WEAKEST. WHILE IT WON`T DRY OUT QUICKLY, THE ZEPHYR ACTS TO LIMIT
THUNDERSTORM DEVELOPMENT BEHIND ITS LEADING EDGE. I WOULD NOT BE
SURPRISED IF THE TAHOE BASIN IS COMPLETELY DRY AS EARLY AS MONDAY
AND POSSIBLY THE SIERRA FRONT OUTSIDE THE PINE NUTS.
TUESDAY THROUGH THURSDAY, DRY SOUTHWEST FLOW WILL CONTINUE. ONE
THING TO NOTE IS THAT THERE IS ANOTHER WAVE EMBEDDED IN THE FLOW FOR
TUESDAY THAT COULD BACK THE FLOW TO THE SOUTH OVER MONO/MINERAL AND
KEEP THUNDERSTORMS POSSIBLE THERE. THE EC IS SHOWING THIS IDEA,
WHILE THE GFS IS DRY. WILL KEEP TUESDAY DRY FOR NOW UNTIL THERE IS
MORE CONSISTENCY.
AS FOR THE WINDS, THEY LOOK TO BE FAIRLY TYPICAL FOR MIDSUMMER WITH
AN AFTERNOON/EVENING ZEPHYR EACH DAY AND GUSTS 25-30 MPH.
TEMPERATURES WILL ALSO COOL BACK CLOSER TO AVERAGE IF NOT A LITTLE
BELOW. WALLMANN
&&
.AVIATION...
VFR CONDITIONS AS MONSOONAL MOISTURE STREAMS NORTH TODAY WITH
BROKEN MID AND HIGH CLOUDS. A FEW LIGHT SHOWERS POSSIBLE THIS
MORNING WITH ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON
ALONG AND JUST EAST OF THE SIERRA. COVERAGE MAY BE MORE OVER MONO
COUNTY INCLUDING KMMH, BUT THIS WILL BE DEPENDENT ON CLOUD COVER
THIS MORNING. MAIN THREAT WILL BE GUSTY OUTFLOW WINDS 40+ KTS AND
ASSOCIATED WIND SHEAR.
MORE CLOUDS TONIGHT BEFORE A POTENTIAL REPEAT ON SATURDAY. MOISTURE
INCREASES, BUT THE STORM COVERAGE WILL BE DEPENDENT ON CLOUD COVER.
WALLMANN
&&
.FIRE WEATHER...
MAIN CONCERN WILL BE LIGHTNING TODAY WITH STORMS AS MOISTURE
CONTINUES TO INCREASE. CLOUD COVER IS FAIRLY EXTENSIVE THIS
MORNING SO COVERAGE IS LIKELY TO REMAIN ISOLATED. STORMS WILL
START DRY AND BECOME WET/DRY HYBRIDS AS THE DAY PROGRESSES. AS WE
MOVE INTO SATURDAY, MOISTURE WILL CONTINUE TO INCREASE AND EXPECT
HYBRID STORMS THAT DAY. GIVEN THE DRYNESS AND HEAT PRECEDING, IT
COULD BE A POTENTIALLY ACTIVE DAY. HOWEVER, CLOUD COVER LOOKS LIKE
IT MIGHT BE EXTENSIVE THAT WOULD REDUCE THE INSTABILITY AND
COVERAGE OF STORMS. GIVEN THE UNCERTAINTY, WILL NOT ISSUE A FIRE
WEATHER WATCH FOR DRY LIGHTNING.
AS WE MOVE INTO SUNDAY, MORE MOISTURE WILL BE PRESENT AND STORMS
WILL BE SLOW MOVING. AT THAT POINT, HEAVY RAIN WILL BE THE BIGGER
CONCERN ALTHOUGH A FEW STARTS OUTSIDE THE CORES WILL REMAIN
POSSIBLE. HUMIDITY WILL ALSO BE HIGHER TOO WITH MINIMUMS LIKELY TO
REMAIN ABOVE 20% IN WESTERN NV AND 30% IN THE SIERRA. DRY SOUTHWEST
FLOW IS EXPECTED NEXT WEEK WITH A FEW STORMS POSSIBLE MONDAY. WINDS
NEXT WEEK LOOK TO BE TYPICAL ZEPHYRS WITH GUSTS 25-30 MPH. WALLMANN
&&
.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 GOODLAND KS
518 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
UPPER RIDGE OVER THE GREAT BASIN WILL GRADUALLY BUILD OVER THE
CENTRAL ROCKIES AND BE THE DOMINANT FEATURE OF THE SHORT TERM
PERIOD. AS A RESULT...PRECIPITATION CHANCES WILL BE RATHER LOW AND
TEMPERATURES WILL BE WARMING. THAT BEING SAID...MAY SEE AN ISOLATED
STORM OR TWO THIS AFTERNOON IN NORTHEAST COLORADO AS HINTED AT BY
THE HRRR NEAR A WEAK SURFACE CONVERGENCE LINE. ENVIRONMENT WILL
BE SIMILAR TO YESTERDAY SO CANT TOTALLY RULE OUT A SEVERE STORM
CAPABLE OF PRODUCING STRONG WINDS...BUT THINK COVERAGE WILL BE
VERY LIMITED DUE TO LACK OF UPPER SUPPORT. SOME OF THE HIRES NAM
MEMBERS PAINT A SIMILAR SCENARIO SATURDAY AFTERNOON IN NORTHEAST
COLORADO SO CARRIED SOME LOW POPS. ONCE AGAIN SEVERE PARAMETERS
ARE FAIRLY DECENT SHOULD SOMETHING DEVELOP. PERHAPS THE NEXT BEST
CHANCE FOR THUNDERSTORMS WILL BE SUNDAY AFTERNOON AND EVENING WITH
SOMEWHAT BETTER LOOKING TROUGH COMING OUT OF COLORADO AND TOPPING
THE RIDGE AXIS IN THE CENTRAL PLAINS. HOWEVER NOT ENOUGH
CONFIDENCE AT THIS POINT WITH THE STRONG RIDGE IN PLACE THAT IT
WILL ACTUALLY PLAY OUT THAT WAY SO WILL ONLY CARRY SILENT 10 POPS
OR LESS.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 516 AM MDT FRI JUL 31 2015
PATCHY DENSE FOG WILL IMPACT KGLD THROUGH ABOUT 14Z BEFORE
CLEARING. VISIBILITIES HAVE BEEN HIGHLY VARIABLE BUT AS LOW AS
1/4SM AT TIMES. OTHERWISE...VFR EXPECTED AT BOTH KGLD AND KMCK
THROUGH THE REMAINDER OF THE TAF PERIOD WITH RIDGING ALOFT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...024
LONG TERM...JBH
AVIATION...024
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
937 AM EDT FRI JUL 31 2015
.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE OHIO VALLEY WITH A TROUGH
OVER EASTERN CANADA. A WEAK FRONT WILL SINK SOUTH ACROSS THE AREA
THIS EVENING. HIGH PRESSURE WILL EXPAND OVER THE LOWER LAKES REGION
ON SATURDAY...SHIFTING TO THE EAST ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST HRRR MODEL APPEARS TO BE BACKING OFF ON CHANCES FOR
PRECIPITATION LATER THIS AFTERNOON. WILL KEEP THE MENTION OF A
SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS AS SURFACE TROUGH
SLIPS EAST ACROSS THE REGION. OTHERWISE...NO MAJOR CHANGES TO THIS
UPDATE.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
ALTHOUGH THE FRONT WILL BE EAST OF THE AREA BY SATURDAY
MORNING...A WEAK THERMAL TROUGH IN THE VICINITY OF EASTERN LAKE
ERIE COULD RESULT IN SOME CLOUDS AND MOISTURE LINGERING IN THE NE
COUNTIES. WILL HOLD ONTO A SLIGHT CHANCE POP ON SATURDAY MORNING
IN NW PA...EXPANDING TO NORTHWEST OHIO BY AFTERNOON AHEAD OF
ANOTHER SHORTWAVE. TEMPERATURES ON SATURDAY WILL BE A LITTLE
COOLER IN THE UPPER 70S/LOW 80S.
SURFACE HIGH PRESSURE EXPANDS EASTWARD ON SATURDAY NIGHT AND SUNDAY
AHEAD OF THE NEXT TROUGH TO APPROACH FROM THE NORTHWEST. THIS
FEATURE DEVELOPS AHEAD OF A SLIGHTLY STRONGER UPPER LEVEL WAVE
DROPPING SOUTH ACROSS CANADA. BETTER MOISTURE ADVECTION IS EXPECTED
AHEAD OF THIS NEXT TROUGH WITH CHANCES OF SHOWERS AND THUNDERSTORMS
DEVELOPING SUNDAY AFTERNOON IN THE NORTH...AND EXPANDING TO ALL
AREAS FOR SUNDAY NIGHT AND MONDAY. SEASONAL TEMPERATURES WILL
CONTINUE.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
THE MODELS LOOK SIMILAR THROUGH MID WEEK WITH THE FRONT
INITIALLY STALLING SOMEWHERE NEAR THE OHIO VALLEY. THIS MAKES FOR A
CHANCE FOR SOME OVER RUNNING SHOWERS...MAINLY ACROSS THE SOUTHERN
PORTION OF THE FORECAST AREA. STILL NOT A LOT OF CONFIDENCE ON THE
THREAT OF RAIN BUT WILL INCLUDE A SMALL CHANCE IN THE SOUTH. 850 MB
TEMPERATURES MAY GET COLD ENOUGH FOR LAKE EFFECT RAIN SHOWERS
ALTHOUGH THERE MAY BE ENOUGH SUBSIDENCE AND SHEAR THAT NOTHING
MATERIALIZES. IT IS WORTH A MENTION BY TUESDAY NIGHT INTO
WEDNESDAY.
THE MODELS REMAIN FAR APART BY NEXT THURSDAY WITH THE GFS
CONTINUING TO DRIVE THE FRONT WELL SOUTH OF THE AREA AND THE ECMWF
DEVELOPING ANOTHER OVER RUNNING WAVE THAT COULD AT LEAST CATCH THE
SOUTHERN PART OF THE FORECAST AREA. WILL CONTINUE TO FAVOR THE DRY
FORECAST...ONE WOULD EXPECT THE SURFACE HIGH TO BUILD SOUTH AT
SOME POINT GIVEN THE DEEPENING TROUGH ALOFT.
SHAVED OFF A DEGREE OR TWO ON FORECAST HIGH TEMPERATURES MID WEEK
GIVEN THE THREAT FOR CLOUDS AND SHOWERS AND THE COOL FLOW. TEMPS
COULD BE COOLER THAN FORECAST...ESPECIALLY IF IT WAS TO BE CLOUDY
AND RAINY BUT WITH THE DAYS SO LONG AND WARM IN EARLY AUGUST WILL
STAY WITHIN 10 DEGREES OF NORMAL FOR NOW.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A CHUNK OF HIGH PRESSURE AT THE SURFACE WAS OVER THE OHIO VALLEY
SLIDING EAST. A WEAK COLD FRONT/TROUGH OVER THE NORTHERN GREAT
LAKES WILL DROP ACROSS THE AREA LATE THIS AFTERNOON AND EVENING.
WEST WINDS WILL GET A BIT GUSTY THIS AFTERNOON AHEAD OF THE
TROUGH. MOISTURE IS VERY LIMITED BUT THERE SHOULD BE SOME CAPE
DEVELOP IN THE HEATING OF THE DAY. AN INCREASE IN SHEAR IS
PROGGED. A FEW THUNDERSTORMS COULD POP UP. COVERAGE WILL LIKELY BE
SMALL BUT THE THREAT IS MENTIONED IN THE CURRENT TAF FORECASTS AS
"VICINITY" AND WILL CONTINUE WITH THAT FORECAST LATE THIS
AFTERNOON INTO TONIGHT.
OUTLOOK...NON VFR POSSIBLE SUNDAY AFTERNOON AND MONDAY IN
SHRA/TSRA.
&&
.MARINE...
WITH A RELATIVELY FAST FLOW ALOFT...EACH WEAK FRONT/TROUGH WILL
PRODUCE THE POSSIBILITY OF SMALL CRAFT ADVISORY CONDITIONS ON LAKE
ERIE...MAINLY THE EAST HALF OF THE LAKE SINCE THE FLOW IS WEST
SOUTHWEST. A WEAK TROUGH IS EXPECTED THIS EVENING AND WILL POST A
SMALL CRAFT ADVISORY FOR THE ERIE COUNTY PA LAKESHORE FROM EARLY
AFTERNOON INTO TONIGHT. THE MAJORITY OF THE WIND WILL BE OVER THE
EAST THIRD OF THE LAKE BUT 4 FOOT WAVES ARE CERTAINLY POSSIBLE
AT ERIE PA LATER TODAY INTO TONIGHT.
THE NEXT WEAK FRONT/TROUGH WILL BE LATER SUNDAY WITH A STRONGER COLD
FRONT ON MONDAY. BOTH OF THOSE SYSTEMS MAY WELL REQUIRE A SMALL
CRAFT ADVISORY...ESPECIALLY FOR THE EAST LAKESHORE.
HIGH PRESSURE WILL BUILD ACROSS THE NORTHERN LAKES NEXT WEEK AND THE
FLOW WILL LIKELY VEER MORE FROM THE NORTH BY MID WEEK.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...BEACH HAZARDS STATEMENT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT FOR PAZ001.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 2 AM EDT
SATURDAY FOR LEZ149.
&&
$$
SYNOPSIS...KEC
NEAR TERM...LOMBARDY
SHORT TERM...KEC
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS NORMAN OK
614 AM CDT FRI JUL 31 2015
.DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
&&
.AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED.
SOME MVFR...PERHAPS IFR...CONDITIONS MAY AFFECT KWWR AND KGAG
THROUGH 16Z.
ISO-SCT SHRA/TSRA WILL BE OVER THE AREA FOR THE NEXT 24 HOURS.
ONLY INCLUDED VCTS AND VCSH NEAR KOKC AND KOUN THROUGH 16-17Z
WHERE CONFIDENCE OF OCCURRENCE IS HIGHER. PINPOINTING WHERE AND
WHEN SHRA/TSRA OCCUR REMAINS VERY TRICKY AND CHALLENGING...SO DID
NOT MENTION IN MANY TAFS AS COVERAGE SHOULD BE LOW. BRIEF MVFR OR
LOWER CONDITIONS AND VARIABLE GUSTY WINDS ARE POSSIBLE WITH
SHRA/TSRA.
MBS
&&
.PREV DISCUSSION... /ISSUED 309 AM CDT FRI JUL 31 2015/
DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 71 91 71 / 20 10 10 20
HOBART OK 94 71 89 70 / 20 30 30 20
WICHITA FALLS TX 96 74 96 73 / 20 20 20 20
GAGE OK 88 68 86 67 / 20 20 20 30
PONCA CITY OK 91 71 91 72 / 20 10 10 20
DURANT OK 96 73 97 73 / 20 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
84/17/17
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1044 AM EDT FRI JUL 31 2015
.SYNOPSIS...
DRY HIGH PRESSURE WILL BUILD IN BEHIND A DEPARTING COLD FRONT TODAY
AND REMAIN IN PLACE THROUGH THE WEEKEND. LOW LEVEL MOISTURE WILL
GRADUALLY RETURN THROUGH NEXT WEEK AS ANOTHER COLD FRONT APPROACHES
FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM EDT FRIDAY...FORECAST RUNNING PRETTY MUCH ON TRACK
WITH NOT MUCH IN THE WAY OF SENSIBLE WEATHER TO WRITE HOME ABOUT.
DESPITE THE HEAT...A FAIRLY NICE DAY WITH DEWPOINTS LOWER IN THE
WAKE OF THE WEAK FRONTAL PASSAGE. VERY LITTLE CHANGES MADE TO THE
GRIDS THIS MORNING...HAVE UPDATED TEMPS AND DEWPOINTS BASED ON
TRENDS AND IT IS POSSIBLE THAT HIGHS MIGHT BE JUST A TOUCH LOWER
THAN FORECAST BUT WILL CONTINUE TO MONITOR. POPS LOOK GOOD FOR
NOW...SPC DAY1 OUTLOOK DOES INCLUDE EXTREME SOUTHEAST PORTIONS OF
THE CWA IN GENERAL THUNDER BUT LOOKING AT THE HRRR AND OTHER CAMS
SEEMS WE WILL BE PRETTY HARD-PRESSED TO SEE CONVECTION TODAY. CLOUDS
WILL CONTINUE TO SCATTER OUT OVER THE NEXT COUPLE OF HOURS.
1045 UTC UPDATE...SKY COVER WAS UPDATED FORM INFRARED SATELLITE
IMAGERY...RESULTING IN A DECREASE. POPS WERE ADJUSTED DOWN PER
TRENDS.
AT 300 AM EDT FRIDAY...AN UPPER RIDGE WILL SLOWLY RETROGRESS TODAY AND
TONIGHT FROM THE SOUTHERN PLAINS TO THE SOUTHERN ROCKIES...WHILE AN
UPPER TROUGH AMPLIFIES OVER THE EASTERN USA. A COLD FRONT WILL MOVE
SLOWLY SOUTH AND OUT OF OUR AREA...STALLING NEAR THE COAST OF THE
CAROLINAS AND GA. MOISTURE ASSOCIATED WITH THIS BOUNDARY APPEARS TO
GENERALLY REMAIN JUST SE OF OUR AREA...OFFERING LITTLE SUPPORT FOR
CONVECTION. TEMPERATURES WILL RUN NEAR NORMAL TODAY AND TONIGHT AS
WEAK COOL ADVECTION IS OFFSET BY LIMITED DOWNSLOPE WARMING FLOW IN
LIGHT NORTHERLY WINDS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 150 AM FRIDAY...QUIET WEATHER EXPECTED THRU THE SHORT RANGE.
AN UPPER TROF REMAINS ACROSS MUCH OF THE ERN CONUS WITH NO
SIGNIFICANT SHORT WAVE ENERGY MOVING THRU THE TROF. AT THE SFC...
DRY HIGH PRESSURE BUILDS IN ACROSS THE AREA SAT AND SUN. GUIDANCE
BLEND SHOWS DEW POINTS MIXING OUT INTO THE 50S ACROSS THE AREA BOTH
DAYS. THIS COMBINED WITH RELATIVELY WARM MID LEVEL AIR WILL LEAD TO
LITTLE TO NO CAPE EACH AFTERNOON...RESULTING IN VERY LOW POTENTIAL
FOR DEEP MOIST CONVECTION. A REMNANT COLD FRONT BOUNDARY WILL BE
CLOSE BUT SOUTH OF THE AREA PROVIDING LITTLE TO NO LOW LEVEL
CONVERGENCE FOR THE AREA. THEREFORE...HAVE GONE WITH A DRY FCST.
EXPECT TEMPS TO BE NEAR TO A LITTLE ABOVE NORMAL THRU THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 255 AM FRIDAY...GUIDANCE IS IN DECENT AGREEMENT THRU THE
PERIOD. EAST COAST TROF FLATTENS THRU THE PERIOD WITH WLY FLOW
DEVELOPING ACROSS THE AREA AS HEIGHTS RISE. THIS ALLOWS A SERIES OF
SHORT WAVES TO MOVE ACROSS OR NEAR THE AREA. THE DRY HIGH PRESSURE
OVER THE AREA SLOWLY MODERATES THEN DISSIPATES AS A COLD FRONT DROPS
SOUTH TOWARD THE AREA. THE COLD FRONT INITIALLY STALLS...THEN MOVES
INTO THE AREA THU AS A LOW PRESSURE AREA TRACKS FROM THE OH VALLEY
OFF THE MID ATLANTIC COAST. THE RESULT IS AN INCREASE IN LOW LEVEL
MOISTURE AND INSTABILITY THRU THE PERIOD. THE BEST FORCING...AND
RESULTANT CONVECTION...WILL BE WED AND THU...WITH A DRY FCST MON AND
ONLY ISOLATED CONVECTION TUE ACROSS THE MTNS. WITH THE RISING
HEIGHTS AND LINGERING HIGH PRESSURE MON AND TUE...TEMPS WILL BE
ABOVE NORMAL. TEMPS SLOWLY FALL WED AND THU...BUT REMAIN ABOVE
NORMAL.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AT KCLT...VFR. GUIDANCE DOES NOT FAVOR VSBY OR CIG RESTRICTIONS.
WINDS WILL GENERALLY FAVOR THE N OR NE...WITH LIMITED GUST
POTENTIAL. CONVECTION IS NOT EXPECTED TODAY IN DRIER AIR BEHIND A
DEPARTING COLD FRONT.
ELSEWHERE...RESTRICTIONS ARE NOT FAVORED AT TAF SITES BY MODEL
GUIDANCE...AS DRIER AIR MOVES IN BEHIND A DEPARTING COLD FRONT.
WINDS WILL GENERALLY FAVOR THE N...WITH ONLY LIMITED GUSTS.
CONVECTION IS NOT EXPECTED AT TAF SITES THIS AFTERNOON.
OUTLOOK...EXPECTING GENERALLY DRY AND QUIET WEATHER THROUGH THE
WEEKEND WITH A GRADUAL INCREASE IN CHANCES FOR SHOWERS/THUNDERSTORMS
AND RESTRICTIONS 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 100% HIGH 100% HIGH 100% HIGH 95%
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...RWH
NEAR TERM...TDP
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JAT/TDP
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1050 AM CDT FRI JUL 31 2015
.UPDATE...
ONE NOTE...AFTER CHECKING THROUGH THE TEMPERATURES DECIDED TO UP
THE HIGHS FOR TODAY A BIT TO BE MORE IN LINE WITH THE MAV
GUIDANCE. DRIER AIR FILTERING IN FROM THE NORTHEAST WILL LIKELY
AID IN A BIT HIGHER NUMBERS.
40
&&
.PREV DISCUSSION... /ISSUED 1036 AM CDT FRI JUL 31 2015/
DISCUSSION...
A COLD FRONT WAS ENTERING INTO THE NORTHEASTERN COUNTIES OF THE
FORECAST AREA AT MID MORNING...WITH A PREFRONTAL TROUGH ACROSS
GALVESTON BAY THROUGH METRO HOUSTON AND INTO THE CLL AREA. ANOTHER
TROUGH WAS OUT IN THE OPEN WATERS OF THE GULF. ISOLATED SHOWERS
HAVE ENDEAVORED TO DEVELOP OVER THE INLAND AREAS SOUTH OF THE
PREFRONTAL TROUGH WHILE SCATTERED LARGER SHOWERS WERE OVER THE
OPEN WATERS OF THE GULF EAST OF THAT SURFACE TROUGH.
THE HIGH RES SHORT RANGE MODELS LOOKED FAIRLY SIMILAR FOR THE
OUTLOOK TODAY. LIKED THE HRRR WHICH HAS ISOLATED CONVECTION ALONG
AND SOUTHWEST OF A LINE FROM ABOUT CLL TO HOUSTON TO GALVESTON
LATE THIS MORNING THROUGH THE EARLY AFTERNOON. AS THE FRONT
CONTINUES MOVING SOUTHWESTWARD...THE RAIN CHANCES WILL PUSH MORE
OVER THE SOUTHWESTERN COUNTIES DURING THE LATE AFTERNOON AND EARLY
EVENING.
THE OTHER ISSUE OF NOTE WILL BE THE HEAT INDEX. VALUES ARE STILL
FORECAST TO REACH ADVISORY CRITERIA OVER THE COAST DURING THE LATE
AFTERNOON PERIOD. THE DRIER AIR BEHIND THE FRONT WILL LIKELY HAVE
AN IMPACT OVER CHAMBERS AND MAYBE GALVESTON COUNTY. SINCE THE
TIMING IS UNCERTAIN AT THIS TIME...WILL KEEP THE HEAT ADVISORY UP
FOR THE IMMEDIATE COASTAL COUNTIES BUT WILL DROP COUNTIES LATER
TODAY IF NEEDED.
TWEAKED THE POPS AND WEATHER A BIT TO ACCOUNT FOR THE LATEST RADAR
AND MODEL TRENDS.
40
PREV DISCUSSION... /ISSUED 414 AM CDT FRI JUL 31 2015/
DISCUSSION...
OVERNIGHT CONVECTION OVER THE BRAZOS VALLEY CONTINUES TO DIMINISH
AS IT EXITS THE FORECAST AREA...WITH VERY WARM TEMPERATURES
PERSISTING ACROSS SOUTHEAST TEXAS EARLY THIS MORNING. SURFACE
ANALYSIS AT 05Z SHOWED A PLUME OF 75+ DEGREE DEW POINTS DRAPED
ALONG THE TEXAS COAST AND EXTENDING INTO NORTHEAST LOUISIANA.
THIS... COMBINED WITH LEFTOVER CLOUDS FROM LAST NIGHT/S STORMS...
WAS CONTRIBUTING TO HEAT INDICES IN THE LOW TO MID 90S AS OF 3 AM
CDT AT A FEW SITES. A WEAK FRONTAL BOUNDARY WAS ALSO ANALYZED ON
THIS MAP STRETCHING NORTH TEXAS AND ON INTO NORTHERN LOUISIANA.
THIS FRONT WILL PLAY A MAJOR ROLE IN HOW THE WEATHER EVOLVES TODAY
FOR THE REGION... BOTH IN TERMS OF THUNDERSTORM CHANCES AS WELL AS
CONCERNS ABOUT HEAT.
THE 00Z LAKE CHARLES SOUNDING REPORTED A PRECIPITABLE WATER VALUE
OF 2.26 INCHES... WITH OVERNIGHT GPS-MET MEASUREMENTS ACROSS THE
REGION SHOWING A SIMILARLY MOIST AIRMASS /2.1 TO 2.3 INCHES AROUND
THE HOUSTON METRO AND ALONG THE COAST/. HIGH RESOLUTION GUIDANCE
IS FAIRLY CONSISTENT WITH DEVELOPING SCATTERED SHOWERS AND
THUNDERSTORMS ALONG THE FRONT AS IT SLOWLY DROPS SOUTHWESTWARD
TODAY... BUT AGREEMENT IS POOR IN THE ACTUAL TIMING OF THIS
FEATURE AND CONSEQUENTLY THE LOCATION OF THE GREATEST AREAL
COVERAGE.
THE GFS APPEARS TO BE BY FAR THE MOST AGGRESSIVE AND SWEEPS
MOISTURE AWAY FROM THE INTERSTATE 45 CORRIDOR AND POINTS EAST BY
18Z. COMPARISON OF SURFACE THETA-E FIELDS HOWEVER /WHICH REPRESENT
MOISTURE AND INSTABILITY PRESENT/ REVEAL STABILIZATION FOR THE
EASTERN HALF OF THE REGION CLOSER TO 00Z... WITH RELATIVELY GOOD
AGREEMENT BETWEEN BOTH HIGHER RESOLUTION AND SYNOPTIC MODELS ON
THIS SOLUTION. BASED ON THIS... HIGHLIGHTING HIGHEST RAIN CHANCES
WEST OF THE INTERSTATE 45 CORRIDOR TODAY ALONG AND AHEAD OF THE
ANTICIPATED FRONTAL POSITION. ADDITIONALLY... A DRY SUB-CLOUD
LAYER AND DCAPE VALUES 1100-1300 J/KG THIS AFTERNOON RAISES
CONCERNS FOR AT LEAST AN ISOLATED GUSTY WIND THREAT FROM STRONGER
THUNDERSTORM ACTIVITY.
A LATER FRONTAL PASSAGE ALSO MEANS THAT STIFLING CONDITIONS WILL
PERSIST AHEAD OF THE FRONT TODAY AND HAVE GONE AHEAD AND ISSUED A
HEAT ADVISORY FOR THE COASTAL COUNTIES OF MATAGORDA... BRAZORIA...
GALVESTON... AND CHAMBERS. HEAT INDICES IN THESE AREAS REACHED 109
TO 111 DEGREES YESTERDAY. WITH THE ANTICIPATED SLOW PROGRESSION
OF THE FRONT TODAY COMBINED WITH NAEFS ANOMALIES HIGHLIGHTING
ANOMALOUS TEMPERATURES AGAIN ALONG THE COAST /A RETURN INTERVAL
OF APPROXIMATELY ONCE EVERY 10 YEARS/... WANTED TO HIGHLIGHT THE
INCREASED POTENTIAL FOR HEALTH IMPACTS. IF THE FRONT MOVES THROUGH
FASTER THAN ANTICIPATED HOWEVER... DRIER AIR FILTERING IN BEHIND
THE FRONT WILL ACTUALLY HELP LOWER HEAT INDEX VALUES AND ADVISORY
CRITERIA MAY NOT BE MET.
FOR THE REMAINDER OF THE SHORT TERM... THE FRONT IS EXPECTED TO
PUSH OFF THE COAST TONIGHT. DRIER AIR FILTERING IN BEHIND THE
FRONT WILL HELP LIMIT RAIN CHANCES OVER ALL BUT THE COASTAL WATERS
ON SATURDAY. THIS SLIGHTLY DRIER AIR MAY ALSO ALLOW FOR SOME
OVERNIGHT LOWS IN THE UPPER 60S IN THE PINEY WOODS REGION... WITH
LOW 70S TO NEAR 80 POSSIBLE ELSEWHERE. HIGH TEMPERATURES ARE NOT
EXPECTED TO DIFFER MUCH FROM TODAY ON SATURDAY BUT A DRIER AIRMASS
IN PLACE WILL HELP MITIGATE AGAINST HIGHER HEAT INDEX VALUES.
THE REGION WILL REMAIN ON THE EASTERN PERIPHERY OF THE UPPER RIDGE
ON SUNDAY AND THROUGH THE REST OF THE FORECAST PERIOD... WITH THE
CENTER OF THIS FEATURE SHIFTING A BIT AROUND THE SOUTHERN PLAINS
DURING THIS TIME. LOW THUNDERSTORM CHANCES WILL CONTINUE IN THE
VICINITY OF THE STALLED FRONTAL BOUNDARY WITH DRY CONDITIONS AND
ABOVE NORMAL TEMPERATURES INLAND PERSISTING INTO THE MIDDLE OF
NEXT WEEK.
HUFFMAN
MARINE...
STORMS HAVE DEPARTED THE WATERS BUT MORE COULD COMING LATE THIS
MORNING THROUGH EVENING. WINDS WILL GENERALLY BE VARIABLE NORTHERLY
TO EASTERLY ACROSS THE UPPER TEXAS COASTAL WATERS WITH AN AFTERNOON
SEABREEZE FORMING. EVENTUALLY A DIFFUSE COLD FRONT SAGS OUT INTO THE
GULF WATERS LATE TONIGHT AND WINDS INCREASE SLIGHTLY. 850MB FRONT
APPEARS TO STALL WELL OFFSHORE AND SHOULD BECOME A FOCUS FOR
REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS BUT PROBABLY JUST SE OF THE
UPPER TEXAS COASTAL WATERS. WILL NEED TO KEEP AN EYE ON THE REMAINS
OF THE BOUNDARY SATURDAY AFTERNOON-SUNDAY AS THE GULF IS PLENTY WARM
ENOUGH AND SHEAR RELAXES. MOISTURE SURGES BACK INTO THE AREA LATE
SUNDAY AND SOUTH TO SOUTHEASTERLY FLOW RETURNS AND CONTINUES THROUGH
FRIDAY.
45
AVIATION...
VFR FOR NOW BUT MAY GET A FEW SPOTS WITH MIFG AROUND SUNRISE MAINLY
THE MORE RURAL SITES CXO NORTHWARD. CHALLENGING FORECAST FOR TODAY.
DRY AIR SHOULD INTRUDE INTO THE REGION FROM THE NORTHEAST BUT A FEW
OF THE MODELS APPEAR TOO QUICK TO DRY THINGS OUT. L/V WINDS WILL BE
THE NORTH UNTIL THE DIFFUSE FROPA. AM THINKING THAT CLL-HOU-SGR-LBX
MAY SEE SOME THUNDER CLOSE BY THIS AFTERNOON AND WILL LIKELY ADD
THIS IN THE 12Z PACKAGE IF NOT SOONER. IAH MAY BE ON THE NORTHERN
FRINGE OF WHERE POOLED MOISTURE AND SAGGING BOUNDARY INTERACT SO FOR
NOW WILL PROBABLY LEAVE VCTS OUT BUT IT WILL BE CLOSE. DEEP MIXING
AGAIN TODAY WITH LIGHT WINDS IN THE PROFILE SO STORMS SHOULD BE SLOW
MOVING. DRYING NORTHEASTERLY TO EASTERLY FLOW SHOULD OVERSPREAD
IAH/HOU BY LATE AFTERNOON/EARLY EVENING LEADING TO CLEAR SKIES.
45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 99 73 98 74 99 / 30 10 10 10 10
HOUSTON (IAH) 100 74 98 75 99 / 20 10 10 10 10
GALVESTON (GLS) 95 80 94 81 92 / 30 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: BRAZORIA...CHAMBERS...GALVESTON...MATAGORDA.
GM...NONE.
&&
$$
DISCUSSION...40
AVIATION/MARINE...33
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1036 AM CDT FRI JUL 31 2015
.DISCUSSION...
A COLD FRONT WAS ENTERING INTO THE NORTHEASTERN COUNTIES OF THE
FORECAST AREA AT MID MORNING...WITH A PREFRONTAL TROUGH ACROSS
GALVESTON BAY THROUGH METRO HOUSTON AND INTO THE CLL AREA. ANOTHER
TROUGH WAS OUT IN THE OPEN WATERS OF THE GULF. ISOLATED SHOWERS
HAVE ENDEAVORED TO DEVELOP OVER THE INLAND AREAS SOUTH OF THE
PREFRONTAL TROUGH WHILE SCATTERED LARGER SHOWERS WERE OVER THE
OPEN WATERS OF THE GULF EAST OF THAT SURFACE TROUGH.
THE HIGH RES SHORT RANGE MODELS LOOKED FAIRLY SIMILAR FOR THE
OUTLOOK TODAY. LIKED THE HRRR WHICH HAS ISOLATED CONVECTION ALONG
AND SOUTHWEST OF A LINE FROM ABOUT CLL TO HOUSTON TO GALVESTON
LATE THIS MORNING THROUGH THE EARLY AFTERNOON. AS THE FRONT
CONTINUES MOVING SOUTHWESTWARD...THE RAIN CHANCES WILL PUSH MORE
OVER THE SOUTHWESTERN COUNTIES DURING THE LATE AFTERNOON AND EARLY
EVENING.
THE OTHER ISSUE OF NOTE WILL BE THE HEAT INDEX. VALUES ARE STILL
FORECAST TO REACH ADVISORY CRITERIA OVER THE COAST DURING THE LATE
AFTERNOON PERIOD. THE DRIER AIR BEHIND THE FRONT WILL LIKELY HAVE
AN IMPACT OVER CHAMBERS AND MAYBE GALVESTON COUNTY. SINCE THE
TIMING IS UNCERTAIN AT THIS TIME...WILL KEEP THE HEAT ADVISORY UP
FOR THE IMMEDIATE COASTAL COUNTIES BUT WILL DROP COUNTIES LATER
TODAY IF NEEDED.
TWEAKED THE POPS AND WEATHER A BIT TO ACCOUNT FOR THE LATEST RADAR
AND MODEL TRENDS.
40
&&
.PREV DISCUSSION... /ISSUED 414 AM CDT FRI JUL 31 2015/
DISCUSSION...
OVERNIGHT CONVECTION OVER THE BRAZOS VALLEY CONTINUES TO DIMINISH
AS IT EXITS THE FORECAST AREA...WITH VERY WARM TEMPERATURES
PERSISTING ACROSS SOUTHEAST TEXAS EARLY THIS MORNING. SURFACE
ANALYSIS AT 05Z SHOWED A PLUME OF 75+ DEGREE DEW POINTS DRAPED
ALONG THE TEXAS COAST AND EXTENDING INTO NORTHEAST LOUISIANA.
THIS... COMBINED WITH LEFTOVER CLOUDS FROM LAST NIGHT/S STORMS...
WAS CONTRIBUTING TO HEAT INDICES IN THE LOW TO MID 90S AS OF 3 AM
CDT AT A FEW SITES. A WEAK FRONTAL BOUNDARY WAS ALSO ANALYZED ON
THIS MAP STRETCHING NORTH TEXAS AND ON INTO NORTHERN LOUISIANA.
THIS FRONT WILL PLAY A MAJOR ROLE IN HOW THE WEATHER EVOLVES TODAY
FOR THE REGION... BOTH IN TERMS OF THUNDERSTORM CHANCES AS WELL AS
CONCERNS ABOUT HEAT.
THE 00Z LAKE CHARLES SOUNDING REPORTED A PRECIPITABLE WATER VALUE
OF 2.26 INCHES... WITH OVERNIGHT GPS-MET MEASUREMENTS ACROSS THE
REGION SHOWING A SIMILARLY MOIST AIRMASS /2.1 TO 2.3 INCHES AROUND
THE HOUSTON METRO AND ALONG THE COAST/. HIGH RESOLUTION GUIDANCE
IS FAIRLY CONSISTENT WITH DEVELOPING SCATTERED SHOWERS AND
THUNDERSTORMS ALONG THE FRONT AS IT SLOWLY DROPS SOUTHWESTWARD
TODAY... BUT AGREEMENT IS POOR IN THE ACTUAL TIMING OF THIS
FEATURE AND CONSEQUENTLY THE LOCATION OF THE GREATEST AREAL
COVERAGE.
THE GFS APPEARS TO BE BY FAR THE MOST AGGRESSIVE AND SWEEPS
MOISTURE AWAY FROM THE INTERSTATE 45 CORRIDOR AND POINTS EAST BY
18Z. COMPARISON OF SURFACE THETA-E FIELDS HOWEVER /WHICH REPRESENT
MOISTURE AND INSTABILITY PRESENT/ REVEAL STABILIZATION FOR THE
EASTERN HALF OF THE REGION CLOSER TO 00Z... WITH RELATIVELY GOOD
AGREEMENT BETWEEN BOTH HIGHER RESOLUTION AND SYNOPTIC MODELS ON
THIS SOLUTION. BASED ON THIS... HIGHLIGHTING HIGHEST RAIN CHANCES
WEST OF THE INTERSTATE 45 CORRIDOR TODAY ALONG AND AHEAD OF THE
ANTICIPATED FRONTAL POSITION. ADDITIONALLY... A DRY SUB-CLOUD
LAYER AND DCAPE VALUES 1100-1300 J/KG THIS AFTERNOON RAISES
CONCERNS FOR AT LEAST AN ISOLATED GUSTY WIND THREAT FROM STRONGER
THUNDERSTORM ACTIVITY.
A LATER FRONTAL PASSAGE ALSO MEANS THAT STIFLING CONDITIONS WILL
PERSIST AHEAD OF THE FRONT TODAY AND HAVE GONE AHEAD AND ISSUED A
HEAT ADVISORY FOR THE COASTAL COUNTIES OF MATAGORDA... BRAZORIA...
GALVESTON... AND CHAMBERS. HEAT INDICES IN THESE AREAS REACHED 109
TO 111 DEGREES YESTERDAY. WITH THE ANTICIPATED SLOW PROGRESSION
OF THE FRONT TODAY COMBINED WITH NAEFS ANOMALIES HIGHLIGHTING
ANOMALOUS TEMPERATURES AGAIN ALONG THE COAST /A RETURN INTERVAL
OF APPROXIMATELY ONCE EVERY 10 YEARS/... WANTED TO HIGHLIGHT THE
INCREASED POTENTIAL FOR HEALTH IMPACTS. IF THE FRONT MOVES THROUGH
FASTER THAN ANTICIPATED HOWEVER... DRIER AIR FILTERING IN BEHIND
THE FRONT WILL ACTUALLY HELP LOWER HEAT INDEX VALUES AND ADVISORY
CRITERIA MAY NOT BE MET.
FOR THE REMAINDER OF THE SHORT TERM... THE FRONT IS EXPECTED TO
PUSH OFF THE COAST TONIGHT. DRIER AIR FILTERING IN BEHIND THE
FRONT WILL HELP LIMIT RAIN CHANCES OVER ALL BUT THE COASTAL WATERS
ON SATURDAY. THIS SLIGHTLY DRIER AIR MAY ALSO ALLOW FOR SOME
OVERNIGHT LOWS IN THE UPPER 60S IN THE PINEY WOODS REGION... WITH
LOW 70S TO NEAR 80 POSSIBLE ELSEWHERE. HIGH TEMPERATURES ARE NOT
EXPECTED TO DIFFER MUCH FROM TODAY ON SATURDAY BUT A DRIER AIRMASS
IN PLACE WILL HELP MITIGATE AGAINST HIGHER HEAT INDEX VALUES.
THE REGION WILL REMAIN ON THE EASTERN PERIPHERY OF THE UPPER RIDGE
ON SUNDAY AND THROUGH THE REST OF THE FORECAST PERIOD... WITH THE
CENTER OF THIS FEATURE SHIFTING A BIT AROUND THE SOUTHERN PLAINS
DURING THIS TIME. LOW THUNDERSTORM CHANCES WILL CONTINUE IN THE
VICINITY OF THE STALLED FRONTAL BOUNDARY WITH DRY CONDITIONS AND
ABOVE NORMAL TEMPERATURES INLAND PERSISTING INTO THE MIDDLE OF
NEXT WEEK.
HUFFMAN
MARINE...
STORMS HAVE DEPARTED THE WATERS BUT MORE COULD COMING LATE THIS
MORNING THROUGH EVENING. WINDS WILL GENERALLY BE VARIABLE NORTHERLY
TO EASTERLY ACROSS THE UPPER TEXAS COASTAL WATERS WITH AN AFTERNOON
SEABREEZE FORMING. EVENTUALLY A DIFFUSE COLD FRONT SAGS OUT INTO THE
GULF WATERS LATE TONIGHT AND WINDS INCREASE SLIGHTLY. 850MB FRONT
APPEARS TO STALL WELL OFFSHORE AND SHOULD BECOME A FOCUS FOR
REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS BUT PROBABLY JUST SE OF THE
UPPER TEXAS COASTAL WATERS. WILL NEED TO KEEP AN EYE ON THE REMAINS
OF THE BOUNDARY SATURDAY AFTERNOON-SUNDAY AS THE GULF IS PLENTY WARM
ENOUGH AND SHEAR RELAXES. MOISTURE SURGES BACK INTO THE AREA LATE
SUNDAY AND SOUTH TO SOUTHEASTERLY FLOW RETURNS AND CONTINUES THROUGH
FRIDAY.
45
AVIATION...
VFR FOR NOW BUT MAY GET A FEW SPOTS WITH MIFG AROUND SUNRISE MAINLY
THE MORE RURAL SITES CXO NORTHWARD. CHALLENGING FORECAST FOR TODAY.
DRY AIR SHOULD INTRUDE INTO THE REGION FROM THE NORTHEAST BUT A FEW
OF THE MODELS APPEAR TOO QUICK TO DRY THINGS OUT. L/V WINDS WILL BE
THE NORTH UNTIL THE DIFFUSE FROPA. AM THINKING THAT CLL-HOU-SGR-LBX
MAY SEE SOME THUNDER CLOSE BY THIS AFTERNOON AND WILL LIKELY ADD
THIS IN THE 12Z PACKAGE IF NOT SOONER. IAH MAY BE ON THE NORTHERN
FRINGE OF WHERE POOLED MOISTURE AND SAGGING BOUNDARY INTERACT SO FOR
NOW WILL PROBABLY LEAVE VCTS OUT BUT IT WILL BE CLOSE. DEEP MIXING
AGAIN TODAY WITH LIGHT WINDS IN THE PROFILE SO STORMS SHOULD BE SLOW
MOVING. DRYING NORTHEASTERLY TO EASTERLY FLOW SHOULD OVERSPREAD
IAH/HOU BY LATE AFTERNOON/EARLY EVENING LEADING TO CLEAR SKIES.
45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 98 73 98 74 99 / 30 10 10 10 10
HOUSTON (IAH) 98 74 98 75 99 / 20 10 10 10 10
GALVESTON (GLS) 95 80 94 81 92 / 30 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: BRAZORIA...CHAMBERS...GALVESTON...MATAGORDA.
GM...NONE.
&&
$$
DISCUSSION...40
AVIATION/MARINE...33
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1021 AM CDT FRI JUL 31 2015
.AVIATION/18Z TAFS/...WNW WINDS WILL CONTINUE TO RAMP UP WITH
DECENT MIXING BUT EXPECT SOME DROPOFF THIS EVENING WITH LOSS OF
HEATING. NAM/LATEST HRRR WANT TO GENERATE SOME LIGHT PRECIP INTO
SC WI LATE TNGT BUT WILL LEAVE MENTION OUT OF TAF AT THIS TIME.
WITH SURFACE/850 RIDGE DRAWING CLOSER ON SATURDAY EXPECT AN
OVERALL LIGHTER WIND REGIME.
PC
&&
.PREV DISCUSSION... /ISSUED 312 AM CDT FRI JUL 31 2015/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
IN THE VERY EARLY TERM...AROUND OR JUST BEFORE 7 AM THIS
MORNING...THERE IS A WEAK SURFACE TROF PASSING THROUGH COUPLED WITH
A MID LEVEL TROF UP ABOVE. HIGHER DEWPOINTS ARE SNEAKING UP JUST
AHEAD OF THE FRONT AND SOME OF THE HI RES MODELS QUICKLY GENERATE A
FEW SHOWERS ACROSS SOUTH CENTRAL AREAS...THEN JUST AS QUICKLY WIPE
THEM OUT AS THEY MOVE SOUTHEAST. THERE ISN/T MUCH ON SATELLITE RIGHT
NOW...JUST A FEW CLOUDS OVER SOUTHEAST MN. SO CONFIDENCE THIS IS
GOING TO HAPPEN IS VERY LOW. WILL BE KEEPING AN EYE ON IT THOUGH.
OTHERWISE...LOOK FOR A VERY SIMILAR DAY TO THE LAST COUPLE. PLENTY
OF SUNSHINE WITH VERY STEEP LOW LEVEL LAPSE RATES WITH DEEP MIXING.
TEMPS WILL BE A FEW DEGREES COOLER THAN YESTERDAY...BUT STILL WARM.
DEW POINTS WILL MIX OUT ONCE AGAIN...PRODUCING LOW HUMIDITY.
QUIET AND PLEASANTLY COOL TONIGHT.
SATURDAY AND SUNDAY...FORECAST CONFIDENCE...MEDIUM
HIGH PRESSURE WILL SLIDE SOUTHWARD ON SATURDAY...BUT SHOULD HAVE
ENOUGH OF A REMAINING INFLUENCE TO KEEP IT DRY THROUGH THE DAYTIME
HOURS. SHOULD SEE A GOOD AMOUNT OF SUNSHINE...WITH HIGHS IN THE 80S
ONCE AGAIN.
LOOKS LIKE A DECENT CHANCE FOR STORMS AT TIMES SATURDAY NIGHT
THROUGH SUNDAY NIGHT. FIRST ROUND SATURDAY EVENING AND OVERNIGHT IS
EXPECTED TO COME AS LOW LEVEL JET STRENGTHENS AND MOVES OVERHEAD
AHEAD OF AN APPROACHING SHORTWAVE. SPC IS HIGHLIGHTING THE SOUTHWEST
HALF OF THE FORECAST ARE WITH A MARGINAL TO SLIGHT RISK OF SEVERE
STORMS. NOT SURPRISING GIVEN BEST FORECAST INSTABILITY IN THE
SOUTHWEST...WITH 30-40 KNOTS OF BULK SHEAR ACROSS THE FORECAST AREA.
THINKING THUNDERSTORM COMPLEX WILL DEVELOP UPSTREAM AND THEN ROLL
INTO THE FORECAST AREA.
SUNDAY IS A BIT OF A QUESTION MARK WITH PRECIP CHANCES. MODELS
SHOWING A WEAK WAVE DURING THE DAY WHICH COULD TRIGGER
STORMS...DEPENDING ON HOW QUICKLY THINGS RECOVER AFTER THE OVERNIGHT
ROUND OF STORMS. CURRENTLY...MODELS SHOWING QUITE A BIT OF CAPE
BY AFTERNOON. BETTER CHANCE WILL PROBABLY BE IN THE EVENING HOURS
AS A COLD FRONT ADVANCES INTO THE AREA. GIVEN
SHEAR...INSTABILITY...AND CURRENT TIMING OF FRONT...THINKING SOME
STRONG TO SEVERE STORMS POSSIBLE ONCE AGAIN.
TEMPS FOR SUNDAY ARE A HEADACHE...WITH MODELS ALL OVER THE PLACE.
WILL DEPEND ON TIMING OF SHORTWAVES AND PRECIP...AND RESULTANT CLOUD
COVER DURING THE DAY. PRETTY GOOD SPREAD IN TEMPS ALOFT BETWEEN
REALLY WARM NAM/GFS SOLUTIONS VS SOMEWHAT COOLER ECMWF. STUCK CLOSE
TO CONSENSUS BLEND OF SOLUTIONS GIVEN UNCERTAINTY.
MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE...MEDIUM
COULD SEE A LINGERING SHOWER OR TWO MONDAY MORNING...BUT OTHERWISE
IT LOOKS DRY AS HIGH PRESSURE BEGINS TO BUILD IN FROM THE
NORTHWEST. SHOULD BE DRY THEN TUESDAY UNDER THE HIGH...WITH A
COUPLE SHOWERS POSSIBLY CLIPPING THE SOUTHWEST WEDNESDAY AS A WEAK
WAVE SLIDES THROUGH. HAVE LOW POPS IN FOR THURSDAY AS ANOTHER WAVE
TRAVERSES THE AREA.
HIGH TEMPS MON/TUE LOOK TO BE WITHIN A COUPLE DEGREES OF
NORMAL...COOLING A FEW DEGREES FOR WED/THU UNDER PERSISTENT
NORTHWEST FLOW ALOFT.
AVIATION/12Z TAFS/...
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THERE IS A VERY
SMALL CHANCE OF A SHOWER AT KMSN BEFORE 12Z THIS MORNING...
ASSOCIATED WITH THE PASSING OF A WEAK SURFACE TROUGH. WINDS WILL
AGAIN BE GUSTY OUT OF THE WEST TO NORTHWEST FROM LATE MORNING
THROUGH THE AFTERNOON...DIMINISHING QUICKLY BY EARLY EVENING.
MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT FROM LATE MORNING THROUGH THE
AFTERNOON DUE TO GUSTY WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS.
WINDS WILL DIMINISH QUICKLY EARLY THIS EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
SATURDAY THROUGH THURSDAY...DDV
AREA FORECAST DISCUSSION
NWS TUCSON AZ
225 PM MST FRI JUL 31 2015
.SYNOPSIS...A MORE ACTIVE THUNDERSTORM DAY ACROSS SOUTHEAST ARIZONA
TODAY. ALTHOUGH SOME DRIER AIR WILL MOVE ACROSS THE AREA THIS
WEEKEND INTO NEXT WEEK...THERE WILL BE ENOUGH MOISTURE AROUND FOR A
CHANCE OF SHOWERS AND THUNDERSTORMS...MAINLY ALONG THE INTERNATIONAL
BORDER AS WELL AS THE MOUNTAIN TOPS.
&&
.DISCUSSION...WATER VAPOR IMAGERY AND 31/12Z UPPER-AIR PLOTS SHOW
THE CENTER OF HIGH PRESSURE IN THE GENERAL VICINITY OF THE TEXAS
PANHANDLE...WITH A PACIFIC LOW PRESSURE SYSTEM WELL OFF THE SOUTHERN
CALIFORNIA AND NORTHERN BAJA COASTS.
WHAT A DIFFERENCE 12 HOURS CAN MAKE. YESTERDAYS 31/00Z KTWC SOUNDING
REVEALED A PW OF 1.10 INCHES AND THE 31/12Z KTWC SOUNDING CAME IN
WITH A PW OF 1.68 INCHES. THIS MORNINGS SOUNDING PARAMETERS SHOWED A
MU CAPE OF AROUND 2200 J/KG AND A LIFTED INDEX OF MINUS 6. THE MOST
RECENT RADAR MOSAIC SHOWS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS CONTINUING TO PROGRESS WESTWARD WEST OF AJO AND ORGAN
PIPE. ELSEWHERE ACROSS SOUTHEAST ARIZONA...ISOLATED TO SCATTERED
THUNDERSTORMS HAVE BEEN DEVELOPING DURING THE PAST HOUR OR TWO...
WITH CELLS EXTENDING FROM EAST OF ELOY TO PICTURE ROCKS AND TOWARD
ARIVACA. WEAK SHOWERS HAVE ALSO DEVELOPED OVER PARTS OF THE TUCSON
METRO AS WELL. ADDITIONAL CELLS ARE OCCURRING OVER THE HIGHER
TERRAIN OF GRAHAM...GREENLEE AND SANTA CRUZ COUNTIES...WITH ACTIVITY
MOVING WEST OR WEST NORTHWEST AT 5 TO 10 MPH.
U OF A 12Z WRF/NAM & GFS...AS WELL AS HRRR ALL SUGGEST THAT STORMS
WILL CONTINUE TO BLOSSOM OVER CENTRAL AND WESTERN PORTIONS OF THE
FORECAST AREA THIS AFTERNOON AND PUSH TO THE WEST OR WEST NORTHWEST
EARLY THIS EVENING. ACTIVITY NOT AS WIDESPREAD BETWEEN TUCSON AND
THE NEW MEXICO BORDER...WITH THE EXCEPTION OF THE MOUNTAIN TOPS.
KEPT A MENTION OF BLOWING DUST OVER PARTS OF PIMA AND PINAL COUNTIES
LATE THIS AFTERNOON AND EARLY THIS EVENING AS STORMS EXPECTED TO
FIRE OFF AND MOVE IN THAT GENERAL DIRECTION. THIS ALSO MESHES WELL
WITH THE FORECAST FROM THE PHOENIX OFFICE.
MODELS INDICATE THAT A WEAK DISTURBANCE COMING UP FROM THE SOUTH
WILL MOVE ACROSS SOUTH CENTRAL ARIZONA THIS EVENING AND THEN OVER
SOUTHWEST ARIZONA EARLY SATURDAY AND WESTERN ARIZONA MIDDAY
SATURDAY. AS THIS OCCURS...THIS SYSTEM WILL HELP TO ENHANCE ACTIVITY
THIS AFTERNOON AND EVENING...BUT BY SATURDAY WE SHOULD SEE LESS
THUNDERSTORM ACTIVITY AS THIS SYSTEM WILL BE OVER SRN NEVADA LATE IN
THE AFTERNOON AND MOISTURE IS EXPECTED TO DECREASE A BIT LATE IN THE
AFTERNOON OR INTO THE EVENING.
BY SUNDAY AND CONTINUING THROUGH AROUND WEDNESDAY THE HIGH IS
EXPECTED TO RECONSOLIDATE IN A WEST TO EAST ORIENTATION ACROSS
NORTHERN MEXICO AND THEN MOVE NORTH OVER THE DESERT SOUTHWEST BY
TUESDAY. AS A RESULT...DRIER SOUTHWEST TO WEST FLOW WILL REDUCE RAIN
CHANCES A BIT AND KEEP THE BEST THREAT FOR SHOWERS AND
THUNDERSTORMS...MAINLY BETWEEN NOGALES AND DOUGLAS AS WELL AS THE
WHITE MOUNTAINS. THIS WILL ALSO RESULT IN WARMER DAYTIME TEMPS
MONDAY THROUGH WEDNESDAY.
FOR LATE WEEK THE HIGH WILL SHIFT TOWARD THE EAST AND RESULT IN A
RETURN FLOW FROM THE SOUTH TO SOUTHEAST AND PULL IN MORE MOISTURE
AND INCREASING THUNDERSTORM CHANCES...BUT STILL JUST ISOLATED TO
SCATTERED IN NATURE.
FOR TUCSON...HIGHS WILL BE NEAR NORMAL SATURDAY...THEN 4 TO 7 DEGS
ABOVE NORMAL EACH DAY THROUGH FRIDAY. HOWEVER...THE WARMEST DAY WILL
LIKELY OCCUR TUESDAY. LOWS WILL RANGE FROM 2 TO 4 DEGS ABOVE NORMAL
EACH MORNING. HOWEVER...THE COOLEST MORNINGS WILL LIKELY OCCUR
MONDAY AND TUESDAY.
&&
.AVIATION...VALID THRU 02/00Z.
SCT TO BKN CLOUDS 7-10K FT AGL WITH SCT-NMRS SHRA/TSRA GENERALLY
BEFORE 01/04Z...AND MAINLY WEST OF A LINE FROM KOLS TO KSAD AND IN
THE WHITE MOUNTAINS. BRIEF MVFR CONDITIONS WITH ERRATIC WIND GUSTS
TO 45 KTS POSSIBLE IN AND AROUND THE STRONGER TSRA. AREAS OF BLDU
PSBL W AND NW OF KTUS AFT 31/22Z. OUTSIDE OF STORM INFLUENCES SFC
WINDS WILL GENERALLY BE LESS THAN 12 KTS WITH A FEW HIGHER GUSTS IN
THE AFTERNOON/EARLY EVENING HOURS. SHRA/TSRA WILL OCCUR AGAIN
SATURDAY AFTERNOON...ALTHOUGH WITH LESS COVERAGE THAN TODAY.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
TODAY WITH STRONG OUTFLOW WINDS LIKELY...ESPECIALLY FROM TUCSON
WEST. SATURDAY WILL SEE SLIGHTLY LESS CONVECTION. INCREASING SW
WINDS ALOFT ON SUNDAY WILL BRING DRIER AIR INTO THE REGION FOR
ISOLATED TO SCATTERED THUNDERSTORM COVERAGE TO BEGIN NEXT
WEEK...WITH A FOCUS MAINLY SOUTH AND EAST OF TUCSON. OUTSIDE OF
THUNDERSTORM WIND GUSTS...20-FT WINDS WILL GENERALLY BE TERRAIN
DRIVEN AND LESS THAN 15 MPH. HOWEVER SOME AFTERNOON AND EARLY
EVENING BREEZINESS IS LIKELY DUE TO DAYTIME HEATING...ESPECIALLY
THROUGH THE GILA VALLEY NEAR SAFFORD.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...MOLLERE
AVIATION/FIRE WEATHER...FRENCH
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1234 PM MST FRI JUL 31 2015
.UPDATE...UPDATED AVIATION DISCUSSION...
&&
.SYNOPSIS...
ISOLATED TO SCATTERED STORM ACTIVITY IS ANTICIPATED OVER ARIZONA AND
SOUTHEAST CALIFORNIA AGAIN TODAY. A NOTABLE DOWNTREND IN MOISTURE
FROM WEST TO EAST IS EXPECTED OVER THE WEEKEND. THIS WILL KEEP STORM
CHANCES LIMITED TO SOUTH- CENTRAL ARIZONA WELL INTO NEXT WEEK.
TEMPERATURES WILL NOT CHANGE MUCH DAY TO DAY REMAINING AT OR ABOVE
SEASONABLE AVERAGE.
&&
.DISCUSSION...
ISOLATED STORM ACTIVITY ALREADY GOING THIS MORNING ALONG OUR
BOUNDARY WITH TWC CWA AND ADDITIONAL SHOWERS FURTHER SOUTH. THESE
APPEAR TO BE INFLUENCED BY REMNANTS OF A COUPLE OF OVERNIGHT MCS/S.
THERE ALSO LOOKS TO BE A BACKDOOR FRONT THAT HAS PUSHED THROUGH MUCH
OF NEW MEXICO. SO THERE COULD BE A COUPLE OF MCV/S AFFECTING THE AREA
TODAY...AND SOME OF THE HIGH RES MODELS DEPICT THAT. UNFORTUNATELY
NONE OF THE HIGH RES MODELS HAVE CAPTURED THIS MORNING/S ACTIVITY
VERY WELL...EVEN THE ONES THAT DID HANDLE THE EARLIER MCS/S FAIRLY
WELL. THE HRRR RUNS THIS MORNING HAVE BEEN INDICATING DEVELOPMENT
OVER SOUTH-CENTRAL ARIZONA...INCLUDING THE LOWER DESERTS...EARLIER
IN THE DAY THAN IS TYPICAL. OVERALL...NOT A LOT OF GOOD AGREEMENT
AMONGST THE MODELS ON THE SPATIAL COVERAGE OF STORMS. ONE SIMILARITY
IS THAT THERE SHOULD BE MORE STORMS OVER SOUTH-CENTRAL ARIZONA TODAY
THAN YESTERDAY. WILL MAKE SOME ADDITIONAL UPWARD ADJUSTMENTS TO POPS.
MORE LATER.
&&
.PREVIOUS DISCUSSION 334 AM MST/PDT...
LOOKING AT 00Z SOUNDINGS FROM BOTH TUCSON AND PHOENIX...SOMEWHAT
DRIER COMPARED TO 12Z ON THURSDAY...HOWEVER STILL FAIRLY AVERAGE FOR
THIS TIME OF YEAR FOR PWAT VALUES. AFTER AN ACTIVE EVENING ACROSS
SOUTHEAST ARIZONA AND SOUTHEAST CALIFORNIA...PER LATEST IR SATELLITE
IMAGERY A NICE MCS HAS MADE AN APPEARANCE OVER SONORA AND IS TRACKING
WESTWARD BUT STILL DELIVERING A VAST AMOUNT OF CLOUD COVER AND
ISOLATED LIGHTNING THIS SIDE OF THE BORDER. THE STRUGGLE TODAY WILL
BE CLOUD COVER AND IF IT WILL HINDER CONVECTION OPPORTUNITIES INTO
THE CENTRAL DESERTS.
STILL UNDER THE INFLUENCE OF SOUTH-SOUTHEASTERLY FLOW ON THE BACKSIDE
OF THE HIGH...THE SHORTWAVE FEATURE THAT IS PROVIDING THE LIFT AND
DYNAMICS CONTINUES TO MOVE NORTHWARD INTO THE FOUR CORNERS REGION.
PRECIPITABLE WATER READINGS ARE FORECAST TO REACH 1.65-1.7 INCH
THROUGH SATURDAY EVENING...WHICH AGAIN IS ABOUT PAR FOR THE COURSE
THIS TIME OF YEAR. TWO OUT OF THREE KEY INGREDIENTS FOR STORM
INITIATION ARE PRESENT AND THE THIRD REALLY HINGES ON DAYTIME
HEATING. AS WE SAW A FEW DAYS AGO THE CLOUDS PLAY A LARGE PART IN
WHETHER STORMS WILL INITIATE OR NOT. BOUNDARY LAYER AND OUTFLOW
INTERACTION ALWAYS AIDE WITH DEVELOPMENT. LOCAL MESOSCALE CONVECTIVE
MODELS ALLUDE TO CLOUDS CLEARING BY MID MORNING FOR CENTRAL ARIZONA
AS WELL AS ELEVATED INSTABILITY BY MID-DAY /CLOSE TO 800 J/KG OF
CAPE/ WHICH WOULD LATER BE REALIZED WITH DAYTIME HEATING. ALL THIS
SAID...TODAY COULD PLAY OUT EITHER WITH STABLE CONDITIONS PERSISTING
DUE TO NO CLEARING OR MID TO LATE AFTERNOON CONVECTION WILL INITIATE
SOUTHEAST OF PHOENIX AND PROPAGATE NORTHWARD. I AM TENDING TO LEAN ON
THE CLEARING OUT OPTION.
FORECAST SOUNDINGS INDICATE A DRY BOUNDARY LAYER /7-8 G/KG MIXING
RATIO/ WITH SUFFICIENT HEATING CREATING AN INVERTED-V TYPE SOUNDING
WITH WARMER MAX TEMPS THIS AFTERNOON. INSTABILITY IN PLACE AND
CONVECTION DEVELOPING SOUTHEAST OF PHOENIX WITH A SOUTHEASTERLY
FLOW...SIGNS POINT TO BLOWING DUST. ALL HIGH-RES MODELS TEND TO AGREE
ON A RATHER ACTIVE EVENING ACROSS THE LOWER DESERTS. WHILE NOT A
SLAM-DUNK FLOOD SCENARIO...CAN`T RULE OUT LOCALIZED FLOODING...AS
WELL AS GUSTY WINDS WITH THE STRONGER STORMS.
AFTER TODAY DRIER AIR BEGINS TO FILTER IN WITH A SOUTHWESTERLY FLOW
STARTING TO TAKE SHAPE. SATURDAY HAS LESS THAN IDEAL CONDITIONS FOR
MONSOONAL ACTIVITY ACROSS THE LOWER AND CENTRAL DESERTS WITH MORE OF
A CONFLUENT FLOW. MOUNTAIN LOCATIONS OF EASTERN ARIZONA WILL STILL
SEE A SLIGHT OR BETTER CHANCE FOR AFTERNOON AND EVENING CONVECTION
FOR THE NEXT SEVERAL DAYS...GRADUALLY TRENDING DOWNWARD. SLIGHT
WARMING WILL ALSO TAKE PLACE WITH TEMPERATURES RANGING 102 TO 108
EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
AN ACTIVE START TO THE AFTERNOON WITH QUITE A BIT OF STORM ACTIVITY
ALREADY FIRING OVER THE MOUNTAINS TO THE NORTH AND EAST OF PHOENIX.
EVENTUALLY EXPECTING SOME STORM OUTFLOWS TO ALLOW FOR MORE STORM
DEVELOPMENT OVER THE LOWER DESERTS BY LATE AFTERNOON. CONFIDENCE IN
TIMING FOR STORMS IN THE LOWER DESERTS IS STILL SOMEWHAT LOW...BUT
WE MAY SEE SOME OUTFLOWS INTO THE PHOENIX TERMINALS AS SOON AS 22-
00Z AND THEN A SHOT AT SOME THUNDERSTORMS DURING THE EVENING HOURS.
WIND FORECASTS THROUGH MIDNIGHT ARE RATHER TRICKY DUE TO THE STRONG
LIKELIHOOD OF STORM OUTFLOWS AFFECTING THE AREA. THERE IS POTENTIAL
FOR SOME STRONG WIND GUSTS WITH THESE OUTFLOWS AND VISIBILITY
RESTRICTIONS IN DUST OR RAIN.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
WEST WINDS TO HOLD MOSTLY FOR KIPL THROUGHOUT THE DAY WHILE
SOUTHERLY HEADINGS ARE IN STORE FOR KBLH. SLIGHT CHANCE FOR ISOLATED
THUNDERSTORM DEVELOPMENT INTO THE AFTN ALONG THE CO RIVER
VALLEY...SO AT LEAST VCSH MENTION IS BACK IN THE KBLH TAF FOR THE
AFTN/EVENING HOURS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
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. MINIMUM RH VALUES WILL BEGIN TO SETTLE INTO
THE TEENS WHILE MAKING MOSTLY MODEST TO FAIR OVERNIGHT RECOVERIES.
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. BY MIDWEEK
A SUBTLE RETURN OF GULF MOISTURE MAY BOOST AREA HUMIDITIES...BUT NOT
LINGER MUCH THROUGH THE END OF THE WEEK.
&&
.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...KUHLMAN
FIRE WEATHER...NOLTE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
941 AM MST FRI JUL 31 2015
.SYNOPSIS...
ISOLATED TO SCATTERED STORM ACTIVITY IS ANTICIPATED OVER ARIZONA AND
SOUTHEAST CALIFORNIA AGAIN TODAY. A NOTABLE DOWNTREND IN MOISTURE
FROM WEST TO EAST IS EXPECTED OVER THE WEEKEND. THIS WILL KEEP STORM
CHANCES LIMITED TO SOUTH- CENTRAL ARIZONA WELL INTO NEXT WEEK.
TEMPERATURES WILL NOT CHANGE MUCH DAY TO DAY REMAINING AT OR ABOVE
SEASONABLE AVERAGE.
&&
.DISCUSSION...
ISOLATED STORM ACTIVITY ALREADY GOING THIS MORNING ALONG OUR
BOUNDARY WITH TWC CWA AND ADDITIONAL SHOWERS FURTHER SOUTH. THESE
APPEAR TO BE INFLUENCED BY REMNANTS OF A COUPLE OF OVERNIGHT MCS/S.
THERE ALSO LOOKS TO BE A BACKDOOR FRONT THAT HAS PUSHED THROUGH MUCH
OF NEW MEXICO. SO THERE COULD BE A COUPLE OF MCV/S AFFECTING THE AREA
TODAY...AND SOME OF THE HIGH RES MODELS DEPICT THAT. UNFORTUNATELY
NONE OF THE HIGH RES MODELS HAVE CAPTURED THIS MORNING/S ACTIVITY
VERY WELL...EVEN THE ONES THAT DID HANDLE THE EARLIER MCS/S FAIRLY
WELL. THE HRRR RUNS THIS MORNING HAVE BEEN INDICATING DEVELOPMENT
OVER SOUTH-CENTRAL ARIZONA...INCLUDING THE LOWER DESERTS...EARLIER
IN THE DAY THAN IS TYPICAL. OVERALL...NOT A LOT OF GOOD AGREEMENT
AMONGST THE MODELS ON THE SPATIAL COVERAGE OF STORMS. ONE SIMILARITY
IS THAT THERE SHOULD BE MORE STORMS OVER SOUTH-CENTRAL ARIZONA TODAY
THAN YESTERDAY. WILL MAKE SOME ADDITIONAL UPWARD ADJUSTMENTS TO POPS.
MORE LATER.
&&
.PREVIOUS DISCUSSION 334 AM MST/PDT...
LOOKING AT 00Z SOUNDINGS FROM BOTH TUCSON AND PHOENIX...SOMEWHAT
DRIER COMPARED TO 12Z ON THURSDAY...HOWEVER STILL FAIRLY AVERAGE FOR
THIS TIME OF YEAR FOR PWAT VALUES. AFTER AN ACTIVE EVENING ACROSS
SOUTHEAST ARIZONA AND SOUTHEAST CALIFORNIA...PER LATEST IR SATELLITE
IMAGERY A NICE MCS HAS MADE AN APPEARANCE OVER SONORA AND IS TRACKING
WESTWARD BUT STILL DELIVERING A VAST AMOUNT OF CLOUD COVER AND
ISOLATED LIGHTNING THIS SIDE OF THE BORDER. THE STRUGGLE TODAY WILL
BE CLOUD COVER AND IF IT WILL HINDER CONVECTION OPPORTUNITIES INTO
THE CENTRAL DESERTS.
STILL UNDER THE INFLUENCE OF SOUTH-SOUTHEASTERLY FLOW ON THE BACKSIDE
OF THE HIGH...THE SHORTWAVE FEATURE THAT IS PROVIDING THE LIFT AND
DYNAMICS CONTINUES TO MOVE NORTHWARD INTO THE FOUR CORNERS REGION.
PRECIPITABLE WATER READINGS ARE FORECAST TO REACH 1.65-1.7 INCH
THROUGH SATURDAY EVENING...WHICH AGAIN IS ABOUT PAR FOR THE COURSE
THIS TIME OF YEAR. TWO OUT OF THREE KEY INGREDIENTS FOR STORM
INITIATION ARE PRESENT AND THE THIRD REALLY HINGES ON DAYTIME
HEATING. AS WE SAW A FEW DAYS AGO THE CLOUDS PLAY A LARGE PART IN
WHETHER STORMS WILL INITIATE OR NOT. BOUNDARY LAYER AND OUTFLOW
INTERACTION ALWAYS AIDE WITH DEVELOPMENT. LOCAL MESOSCALE CONVECTIVE
MODELS ALLUDE TO CLOUDS CLEARING BY MID MORNING FOR CENTRAL ARIZONA
AS WELL AS ELEVATED INSTABILITY BY MID-DAY /CLOSE TO 800 J/KG OF
CAPE/ WHICH WOULD LATER BE REALIZED WITH DAYTIME HEATING. ALL THIS
SAID...TODAY COULD PLAY OUT EITHER WITH STABLE CONDITIONS PERSISTING
DUE TO NO CLEARING OR MID TO LATE AFTERNOON CONVECTION WILL INITIATE
SOUTHEAST OF PHOENIX AND PROPAGATE NORTHWARD. I AM TENDING TO LEAN ON
THE CLEARING OUT OPTION.
FORECAST SOUNDINGS INDICATE A DRY BOUNDARY LAYER /7-8 G/KG MIXING
RATIO/ WITH SUFFICIENT HEATING CREATING AN INVERTED-V TYPE SOUNDING
WITH WARMER MAX TEMPS THIS AFTERNOON. INSTABILITY IN PLACE AND
CONVECTION DEVELOPING SOUTHEAST OF PHOENIX WITH A SOUTHEASTERLY
FLOW...SIGNS POINT TO BLOWING DUST. ALL HIGH-RES MODELS TEND TO AGREE
ON A RATHER ACTIVE EVENING ACROSS THE LOWER DESERTS. WHILE NOT A
SLAM-DUNK FLOOD SCENARIO...CAN`T RULE OUT LOCALIZED FLOODING...AS
WELL AS GUSTY WINDS WITH THE STRONGER STORMS.
AFTER TODAY DRIER AIR BEGINS TO FILTER IN WITH A SOUTHWESTERLY FLOW
STARTING TO TAKE SHAPE. SATURDAY HAS LESS THAN IDEAL CONDITIONS FOR
MONSOONAL ACTIVITY ACROSS THE LOWER AND CENTRAL DESERTS WITH MORE OF
A CONFLUENT FLOW. MOUNTAIN LOCATIONS OF EASTERN ARIZONA WILL STILL
SEE A SLIGHT OR BETTER CHANCE FOR AFTERNOON AND EVENING CONVECTION
FOR THE NEXT SEVERAL DAYS...GRADUALLY TRENDING DOWNWARD. SLIGHT
WARMING WILL ALSO TAKE PLACE WITH TEMPERATURES RANGING 102 TO 108
EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
BKN-OVC MID AND HIGH LEVEL CIGS WILL CONTINUE TO DRIFT ACROSS THE
AREA THIS AM FROM DECAYING STORM COMPLEXES SOUTH OF THE BORDER AND
ACROSS SE AZ. HOW FAST AND TO WHAT EXTENT THESE CLEAR TODAY WILL
EITHER HELP OR HURT THE PHX METRO IN TERMS OF STORM CHANCES
IMPACTING THE TERMINALS LATER INTO THE EVENING. GNLY LIGHT AM SFC
WINDS NOTED AT SITES AROUND THE METRO WITH SUBTLE WEST FLOW VIA TPHX
AND KIWA VELOCITIES...SO ELECTED TO GO WITH VRB IN FOR PHX. SPEEDS
SHOULD BE LIGHT AND MANAGEABLE UNTIL MORE PROMINENT WESTERLY FLOW
SETTLES INTO THE AREA AFTER MIDDAY.
IF SKIES CLEAR AND WE ARE ABLE TO DECENTLY WARM THE DESERTS...STORMS
ARE FCST TO BEGIN FIRING OVER THE HIGHER TERRAIN AND FOOTHILLS EAST
AND SOUTH OF PHOENIX. STORM INITIATION AND/OR SURVIVAL INTO THE PHX
METRO WILL LIKELY DEPEND ON STORM OUTFLOWS AND THEIR INTERACTION.
FOLLOWING HOW CONDITIONS HAVE MATERIALIZED SO FAR THIS
SUMMER...THESE OUTFLOW PASSAGES TEND BE POST 00Z...SO DID INCLUDE
VCTS MENTION 01/02Z FOR KSDL AND KIWA AND 01/04Z FOR KPHX.
CONFIDENCE IS MODERATE ON STORM DEVELOPMENT THIS EVENING...HOPING
THAT DAYTIME CLOUD COVER CLEARS ENOUGH TO NOT DAMPEN/SHUT DOWN STORM
CHANCES LATER INTO THE EVENING.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
SCT-BKN MID LEVEL CLOUDS WILL CONTINUE TO STREAM OVER THE TERMINALS
FROM THE SOUTH THROUGH THE AM...OTHERWISE SKIES WILL MAINTAIN FEW-
SCT CLOUD COVERAGE. WEST WINDS TO HOLD MOSTLY FOR KIPL THROUGHOUT
THE DAY WHILE SOUTHERLY HEADINGS ARE IN STORE FOR KBLH. SLIGHT
CHANCE FOR ISOLATED THUNDERSTORM DEVELOPMENT INTO THE AFTN ALONG THE
CO RIVER VALLEY...SO AT LEAST VCSH MENTION IS BACK IN THE KBLH TAF
FOR THE AFTN/EVENING HOURS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
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. MINIMUM RH VALUES WILL BEGIN TO SETTLE INTO
THE TEENS WHILE MAKING MOSTLY MODEST TO FAIR OVERNIGHT RECOVERIES.
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. BY MIDWEEK
A SUBTLE RETURN OF GULF MOISTURE MAY BOOST AREA HUMIDITIES...BUT NOT
LINGER MUCH THROUGH THE END OF THE WEEK.
&&
.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 RENO NV
1007 AM PDT FRI JUL 31 2015
.UPDATE...
MADE A QUICK UPDATE THIS MORNING TO DECREASE COVERAGE OF EXPECTED
THUNDERSTORMS TODAY IN MONO COUNTY TO ISOLATED, INSTEAD OF
SCATTERED. ABUNDANT CLOUD COVER WILL KEEP INSTABILITY MARGINALIZED
THROUGH THE DAY, RESULTING IN LESS THUNDERSTORM POTENTIAL. STILL,
ANY STORMS THAT DO HAPPEN TO FORM WILL HAVE TO OVERCOME A VERY DRY
BOUNDARY LAYER, SO LITTLE RAINFALL IS EXPECTED OVERALL WITH VIRGA
SHOWERS COMMON TODAY. HOON
&&
.PREVIOUS DISCUSSION... /ISSUED 304 AM PDT FRI JUL 31 2015/
SYNOPSIS...
MOISTURE WILL SPREAD NORTH ACROSS THE REGION TODAY AND BRING A
CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY NEAR THE SIERRA AND IN
WESTERN NEVADA SOUTH OF HIGHWAY 50, WITH GUSTY OUTFLOW WINDS AND
LIGHTNING INDUCED FIRE STARTS POSSIBLE. THE BEST OVERALL SHOWER
AND THUNDERSTORM POTENTIAL IS EXPECTED FOR THIS WEEKEND, WITH
LOCALLY HEAVY RAINFALL AND FLOODING BECOMING THE MAIN THREATS.
SHORT TERM...
MID AND HIGH LEVEL MOISTURE CONTINUES TO SPREAD NORTH ACROSS
CALIFORNIA AND NEVADA THROUGH THE EARLY MORNING. ANOTHER WEAK
IMPULSE FARTHER SOUTH ACROSS INYO AND NYE COUNTIES IS BEING
PICKED UP BY THE LATEST NAM AND HRRR GUIDANCE, WHICH SPREAD SOME
SHOWERS ACROSS MONO, ALPINE AND SOUTHERN MINERAL COUNTIES DURING
THE EARLY AND MID MORNING.
FOR THE REMAINDER OF TODAY, FAVORED AREAS FOR AFTERNOON CONVECTION
APPEAR TO BE LIMITED TO AREAS NEAR THE SIERRA FROM MONO COUNTY
NORTHWARD TO WESTERN LASSEN COUNTY, AND IN WESTERN NV SOUTH OF
HIGHWAY 50. ELSEWHERE, THICKER CLOUD COVER SPREADING ACROSS
WESTERN NV AND NORTHEAST CA DURING THE DAY COMBINED WITH DRY EAST
FLOW NEAR THE SURFACE MAY PRODUCE CONDITIONS TOO STABLE FOR
FORMING OR SUSTAINING CONVECTION THAT MOVES NORTH OF HIGHWAY 50.
HOWEVER, OUTFLOWS FROM CELLS THAT DEVELOP NEAR THE SIERRA COULD
PUSH ACROSS WESTERN NV AND BRING A SHORT PERIOD OF STRONGER WIND
GUSTS BY LATE AFTERNOON OR EARLY EVENING. MOST ACTIVITY WILL
DIMINISH TONIGHT, ALTHOUGH A FEW BRIEF CELLS CAN`T BE RULED OUT
MAINLY SOUTH OF HIGHWAY 50 AS MOISTURE CONTINUES TO INCREASE
OVERNIGHT.
THE MAIN CONVECTIVE POTENTIAL IS EXPECTED THIS WEEKEND AS MOISTURE
CONTINUES TO SURGE NORTHWARD. WHILE CLOUD COVER COULD STILL DISRUPT
CONVECTIVE DEVELOPMENT, THERE APPEARS TO BE A LARGER WINDOW OF
HEATING ON SATURDAY, ALONG WITH RISING DEW POINTS CONTRIBUTING TO
MORE INSTABILITY. A STRONGER UPPER LEVEL DISTURBANCE IS ALSO
PROJECTED TO MOVE NORTH ACROSS THE SIERRA WITH ANOTHER DISTURBANCE
TRACKING NORTHWARD ACROSS CENTRAL NV. THESE FEATURES WOULD PROVIDE
ADDITIONAL FORCING AND INCREASE SHOWER AND THUNDERSTORM COVERAGE
WHICH MAY HOLD TOGETHER THROUGH SATURDAY NIGHT. THE CURRENT
SHORTWAVE TRACKS ARE FAVORING SOME OVERNIGHT PRECIP ACROSS THE
TAHOE BASIN AND THE RENO-CARSON CITY VICINITY, ALTHOUGH THIS COULD
VARY SINCE THE TRACK OF THESE DISTURBANCES ARE LIKELY TO CHANGE
WITH UPCOMING MODEL RUNS.
FOR SUNDAY, ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS PROBABLE
WITH VERY MOIST AND UNSTABLE CONDITIONS REMAINING. IF FULL
INSTABILITY IS REALIZED, THEN SOME STRONG STORMS WITH HEAVY RAIN
WOULD DEVELOP. HOWEVER, THERE COULD BE TOO MUCH LEFTOVER CLOUD
COVER FROM SATURDAY NIGHT`S ACTIVITY WHICH LIMITS HEATING AND
CELL STRENGTH ON SUNDAY. THIS LIMITING FACTOR IS MORE PRONOUNCED
ON THE GFS WHICH IS HOLDING MAX TEMPS DOWN TO THE MID-UPPER 80S
ACROSS WESTERN NV. WE DIDN`T MAKE MUCH CHANGE TO THE CURRENT
SUNDAY FORECAST WITH CHANCE POPS KEPT OVER MOST AREAS, SINCE
THERE IS A LOT OF UNCERTAINTY WITH THE DETAILS OF WHERE CONVECTION
EVENTUALLY OCCURS. MJD
LONG TERM...MONDAY THROUGH THURSDAY...
THE OVERALL IDEA FOR NEXT WEEK`S FORECAST HAS NOT CHANGED, BUT DID
MAKE SOME CHANGES TO THE DETAILS. DRIER SOUTHWEST FLOW IS EXPECTED
TO BEGIN MONDAY AND CONTINUE THROUGH THE WEEK. SOME MOISTURE WILL BE
LEFT OVER MONDAY FOR SOME SHOWERS AND THUNDERSTORMS. HOWEVER, PUSHED
THE BEST CHANCES TO MONO/MINERAL WHERE THE SOUTHWEST FLOW WILL BE
WEAKEST. WHILE IT WON`T DRY OUT QUICKLY, THE ZEPHYR ACTS TO LIMIT
THUNDERSTORM DEVELOPMENT BEHIND ITS LEADING EDGE. I WOULD NOT BE
SURPRISED IF THE TAHOE BASIN IS COMPLETELY DRY AS EARLY AS MONDAY
AND POSSIBLY THE SIERRA FRONT OUTSIDE THE PINE NUTS.
TUESDAY THROUGH THURSDAY, DRY SOUTHWEST FLOW WILL CONTINUE. ONE
THING TO NOTE IS THAT THERE IS ANOTHER WAVE EMBEDDED IN THE FLOW FOR
TUESDAY THAT COULD BACK THE FLOW TO THE SOUTH OVER MONO/MINERAL AND
KEEP THUNDERSTORMS POSSIBLE THERE. THE EC IS SHOWING THIS IDEA,
WHILE THE GFS IS DRY. WILL KEEP TUESDAY DRY FOR NOW UNTIL THERE IS
MORE CONSISTENCY.
AS FOR THE WINDS, THEY LOOK TO BE FAIRLY TYPICAL FOR MIDSUMMER WITH
AN AFTERNOON/EVENING ZEPHYR EACH DAY AND GUSTS 25-30 MPH.
TEMPERATURES WILL ALSO COOL BACK CLOSER TO AVERAGE IF NOT A LITTLE
BELOW. WALLMANN
AVIATION...
VFR CONDITIONS AS MONSOONAL MOISTURE STREAMS NORTH TODAY WITH
BROKEN MID AND HIGH CLOUDS. A FEW LIGHT SHOWERS POSSIBLE THIS
MORNING WITH ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON
ALONG AND JUST EAST OF THE SIERRA. COVERAGE MAY BE MORE OVER MONO
COUNTY INCLUDING KMMH, BUT THIS WILL BE DEPENDENT ON CLOUD COVER
THIS MORNING. MAIN THREAT WILL BE GUSTY OUTFLOW WINDS 40+ KTS AND
ASSOCIATED WIND SHEAR.
MORE CLOUDS TONIGHT BEFORE A POTENTIAL REPEAT ON SATURDAY. MOISTURE
INCREASES, BUT THE STORM COVERAGE WILL BE DEPENDENT ON CLOUD COVER.
WALLMANN
FIRE WEATHER...
MAIN CONCERN WILL BE LIGHTNING TODAY WITH STORMS AS MOISTURE
CONTINUES TO INCREASE. CLOUD COVER IS FAIRLY EXTENSIVE THIS
MORNING SO COVERAGE IS LIKELY TO REMAIN ISOLATED. STORMS WILL
START DRY AND BECOME WET/DRY HYBRIDS AS THE DAY PROGRESSES. AS WE
MOVE INTO SATURDAY, MOISTURE WILL CONTINUE TO INCREASE AND EXPECT
HYBRID STORMS THAT DAY. GIVEN THE DRYNESS AND HEAT PRECEDING, IT
COULD BE A POTENTIALLY ACTIVE DAY. HOWEVER, CLOUD COVER LOOKS LIKE
IT MIGHT BE EXTENSIVE THAT WOULD REDUCE THE INSTABILITY AND
COVERAGE OF STORMS. GIVEN THE UNCERTAINTY, WILL NOT ISSUE A FIRE
WEATHER WATCH FOR DRY LIGHTNING.
AS WE MOVE INTO SUNDAY, MORE MOISTURE WILL BE PRESENT AND STORMS
WILL BE SLOW MOVING. AT THAT POINT, HEAVY RAIN WILL BE THE BIGGER
CONCERN ALTHOUGH A FEW STARTS OUTSIDE THE CORES WILL REMAIN
POSSIBLE. HUMIDITY WILL ALSO BE HIGHER TOO WITH MINIMUMS LIKELY TO
REMAIN ABOVE 20% IN WESTERN NV AND 30% IN THE SIERRA. DRY SOUTHWEST
FLOW IS EXPECTED NEXT WEEK WITH A FEW STORMS POSSIBLE MONDAY. WINDS
NEXT WEEK LOOK TO BE TYPICAL ZEPHYRS WITH GUSTS 25-30 MPH. WALLMANN
&&
.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 DENVER/BOULDER CO
1019 AM MDT FRI JUL 31 2015
.UPDATE...
ISSUED AT 1013 AM MDT FRI JUL 31 2015
SATELLITE IMAGERY SHOWING SOME CU START TO DEVELOP OVER THE HIGHER
TERRAIN. HRRR AND RAP CONTINUING TO SHOW STORM DEVELOPMENT OVER
THE DIVIDE THROUGH THE AFTERNOON. SOME OF THE STORMS MAY MOVE OFF
THE MOUNTAINS OVER THE FOOTHILLS OF PARK...JEFFERSON AND DOUGLAS
COUNTIES BY THE EARLY EVENING. BIGGEST THREATS WILL BE BRIEF
MODERATE TO HEAVY RAIN WITH THE POSSIBILITY OF SOME SMALL HAIL AND
WIND GUSTS UP TO 45 MPH WITH THE STRONGER STORMS. TEMPERATURES ARE
STILL ON TRACK TO REACH THE UPPER 80S TO LOWER 90S FOR THE PLAINS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 245 AM MDT FRI JUL 31 2015
THE BROAD UPPER HIGH WILL CONTINUE TO SHIFT FURTHER WEST AND
NORTH ACROSS THE GREAT BASIN TODAY. THIS WILL ALLOW SOME
ADDITIONAL MOISTURE TO ALSO SEEP INTO COLORADO WHERE INTEGRATED PW
VALUES HAVE ALREADY INCREASED AROUND A THIRD OF AN INCH IN THE
PAST 12 HOURS OVER THE FRONT RANGE. STILL THOUGH MID LEVEL
INVERSION AROUND 500MB WILL LIMIT CONVECTION THROUGH THIS
AFTERNOON. NAM SEEMS THE MOST BULLISH ON MOISTURE AND STORM
POTENTIAL WHILE THE THE RAP IS THE DRIEST. EXPECT MAJORITY OF
STORMS WILL BE OVER EAST SLOPES AND HIGHER TERRAIN. SOME OF THIS
MAY SPILL OUT OVER THE ADJACENT PLAINS BY LATER THIS AFTERNOON.
NOT MUCH HELP UPSTAIRS AS QG FIELDS SHOWING SOME SUBSIDENCE IN THE
700MB LAYERS AND NEUTRAL FORCING ALOFT. ISOLATED POPS ON THE
PLAINS WITH HIGHER SCATTERED CHANCES IN THE MOUNTAINS SHOULD
SUFFICE. EXPECT TEMPERATURES WILL BE SIMILAR TO THURSDAY READINGS.
CONVECTION WILL DIMINISH DURING THE EVENING HOURS WITH LACK OF ANY
UPPER AIR SUPPORT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 207 AM MDT FRI JUL 31 2015
BY SATURDAY MORNING...A NEGATIVELY TILTED UPPER RIDGE IS STILL OVER
THE WRN CONUS WITH THE 500MB HIGH OVER SERN NEW MEX. AT THE SFC...
BROAD CLOCKWISE CIRCULATION AROUND A STG HIGH IN NWRN ARKANSAS
CONTINUES TO ADVECT INCREASING AMOUNTS OF LOW-LEVEL MOISTURE
NORTHWARD ALONG THE COLORADO/KANSAS BORDER. MEANWHILE THE MID-LEVEL
NWLY FLOW CONTINUES TO DRY ON THE SOUTH SIDE OF AN 80-90KT JET
SEGMENT. BY LATE AFTERNOON...MODELS SHOW A NEARLY NEUTRAL TILT UPPER
RIDGE MIGRATING EASTWARD OVER ERN UTAH/COLORADO CAUSING THE MID-
LEVEL FLOW OVER THE FCST AREA TO BECOME N-NWLY. AT THE SAME TIME
SELY BNDRY LAYER FLOW EAST OF THE MTNS CONTINUES TO TRANSPORT LOW
LEVEL MOISTURE UP INTO THE FCST AREA. MODELS SHOW MEAN LAYER PW
VALUES PUSHING AN INCH ACRS SERN SECTIONS OF THE CWA BY EVENING.
HOWEVER...MOISTURE APPEARS RELATIVELY SHALLOW...CAPPED BY A MUCH
DRIER N-NWLY FLOW ABOVE 650 MBS. OVERNIGHT SELY SFC WINDS ON THE
PLAINS TURN SWLY WHICH FLUSHES OUT SOME OF THE MOISTURE UP ALONG
THE FRONT RANGE.
DRY OUT IS SHORT-LIVED AS THE GFS...SREF AND NAM SHOW A RETURN TO A
MOIST SELY FLOW DURING THE DAY SUNDAY. MODELS SHOW MEAN LAYER PW
VALUES APPROACH 1.25 INCH OVER NRN PORTIONS OF THE I-25 URBAN
CORRIDOR BY LATE AFTERNOON. THIS TIME THE MOISTURE LAYER APPEARS
DEEPER AND WITH LIGHT/VARIABLE TRANSPORT WINDS SLOW STORM MOTIONS
WOULD CONCEIVABLY RESULT IN LOCALLY HEAVY RAINFALL. ALTHOUGH QPF
FIELDS DO NOT INDICATE ANYTHING LIKE THAT HAPPENING APPARENTLY DUE
TO A LACK OF CAPE AND SOME KIND OF FORCING MECHANISM SUCH AS A
FRONTAL BNDRY OR DEEP UPSLOPE FLOW. HOWEVER MODELS INDICATE CAPES IN
THE 1000-1500 J/KG RANGE...AND ON THE NAM AS HIGH AS 2000 J/KG...AND
DECENT LOW-LEVEL CONVERGENCE/SHEAR ALONG THE PALMER DIVIDE. ITS MORE
LIKELY HERE THAT A FEW SUPERCELLS CAPABLE OF HEAVY RAINFALL...HAIL
AND STG GUSTY WINDS WILL FORM AND TRACK EAST-SOUTHEAST ALONG THE
DIVIDE DURING THE LATE AFTERNOON AND EVENING HRS ON SUN. THE SRN
FRONT RANGE FOOTHILLS AND SOUTH PARK IS ANOTHER AREA WHERE THERE`S
AN ELEVATED POTENTIAL FOR T-STORMS AT THIS TIME DUE TO THIS MOIST
AND UNSTABLE SELY FLOW. ACTUALLY THERE`S A GREATER POTENTIAL FOR
STORMS PRODUCING HEAVY RAINFALL IN PARK COUNTY WITH THIS SET UP.
BY SUNDAY NIGHT...THE NAM...GFS AND ECMWF ALL NOW SHOW A MID-LEVEL
SHORTWAVE TROUGH LIFTING NEWRD ACRS THE STATE WITH THE UPPER RIDGE
COLLAPSING AS IT CONTINUES TO SHIFT EAST. WAVE IS FCST TO REACH THE
FRONT RANGE URBAN CORRIDOR BY EARLY MONDAY MORNING. ITS PASSAGE
COULD ENHANCE OR EXTEND SHOWER/T-STORM DEVELOPMENT IN THE HIGH
COUNTRY THROUGH THE LATE EVENING HRS. NOT SURE THIS DISTURBANCE WILL
HAVE MUCH OF AN IMPACT ON AREAS EAST OF THE MTNS OVERNIGHT.
ON MONDAY...MOISTURE...INSTABILITY AND MODEST QG LIFT ASSOCIATED
WITH THE PASSING SHORTWAVE EXPECTED TO PRODUCE MORE CLOUD COVER AND
A SLIGHTLY GREATER CHANCE OF SHOWERS/T-STORMS FOR THE ENTIRE FCST
AREA. MOST MODELS SHOW THIS FEATURE EXITING THE STATE BY EVENING
WITH DRYING AND STABILIZATION IN ITS WAKE AS THE UPPER RIDGE AXIS
MOVES OVERHEAD OVERNIGHT.
TUESDAY SHOULD BE A DRIER AND SLIGHTLY WARMER DAY WITH ANY STORM
DEVELOPMENT RELEGATED TO THE HIGH COUNTRY. ON WEDNESDAY... TEMPS
CONTINUE TO WARM BOTH SFC AND ALOFT...AND HUMIDITIES LOWER WITH
THE UPPER RIDGE AMPLIFYING OVER THE CENTRAL ROCKIES. HOWEVER STILL
CANNOT RULE OUT A FEW LATE DAY GUSTY T-STORMS IN THE HIGH COUNTRY.
BY THURSDAY...MEDIUM RANGE MODELS SHOW THE UPPER RIDGE MOVING OVER
THE GREAT PLAINS PLACING COLORADO UNDER SWLY FLOW ALOFT. COULD SEE
SUBTROPICAL MOISTURE CARRIED NORTH BY THIS FLOW IN TANDEM WITH A
SHORTWAVE TROUGH THAT MODELS SHOW SWINGING OUT OF THE 4-CORNERS
REGION LATE IN THE DAY. AS A RESULT COULD SEE A MODEST INCREASE IN T-
STORM CHANCES MAINLY FOR THE HIGH COUNTRY. OTHERWISE THURSDAY TEMPS
LITTLE CHANGED FROM THE DAY BEFORE.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SATURDAY MORNING)
ISSUED AT 1013 AM MDT FRI JUL 31 2015
VFR EXPECTED FOR THE NEXT 24 HOURS FOR ALL AIRPORTS. A MID LEVEL
BKN DECK WILL FORM WITH INCREASED MOISTURE IN THE AFTERNOON WITH
SOME SHOWERS IN THE VICINITY. WINDS WILL SLOWLY MAKE THEIR WAY TO
THE SE THEN TRANSITION TO DRAINAGE BY THE EVENING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BOWEN
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
227 PM EDT FRI JUL 31 2015
.NEAR TERM.../TODAY THROUGH SATURDAY/...
SLOW MOVING COLD FRONT OVER CENTRAL GA HAS SE GA/NE FL IN A MOIST
LOW-MID LEVEL SW FLOW. SCATTERED SHOWERS HAVE FORMED OVER NE FL
EARLY THIS AFTERNOON WITH ACTIVITY EXPECTED TO INCREASE OVER SE GA
BY LATE AFTERNOON/EARLY EVENING AS HRRR MODEL INDICATES. SW WINDS
WILL KEEP EAST COAST SEABREEZE NEAR THE COAST TODAY WITH STORMS
EXPECTED TO STRENGTHEN UPON BOUNDARY COLLISIONS. EXPECT A SIMILAR
SCENARIO ON SATURDAY WITH SCATTERED CONVECTION BECOMING NUMEROUS
LATE AFTERNOON/EVENING NEAR THE EAST COAST. TEMPERATURES WILL BE
NEAR AVERAGE LEVELS THIS WEEKEND.
&&
.SHORT TERM.../SATURDAY NIGHT THROUGH TUESDAY/...
TROUGHING WILL PERSIST ACROSS THE REGION THROUGH MONDAY...PROVIDING
AN ACTIVE WEATHER PATTERN WITH DAILY ROUNDS OF AFTERNOON AND EVENING
SHOWERS AND STORMS. THESE STORMS WILL BE INITIATED BY THE
COMBINATION OF CONVERGENCE ALONG THE TROUGH AND DIURNAL INSTABILITY.
WITH THE INCREASED CLOUD AND RAIN COVERAGE TEMPERATURES WILL BE
A LITTLE BELOW NORMAL THROUGH MONDAY.
THE TROUGH WEAKENS...WITH SLIGHT RIDGING FOR TUESDAY. PRECIPITATION
CHANCES WILL BE A LITTLE LESS AS A RESULT...WITH MAIN INITIATION
SOURCES FOR CONVECTION BEING DIURNAL HEATING AND SEA BREEZE
CONVERGENCE. TEMPERATURES WILL RETURN TO NEAR NORMAL READINGS
FOR TUESDAY.
&&
.LONG TERM.../TUESDAY NIGHT THROUGH FRIDAY/...
WEAK RIDGING WILL PERSIST INTO WEDNESDAY. A TROUGH WILL SETTLE
INTO THE SOUTHEASTERN US ONCE AGAIN THURSDAY...WITH PRECIPITATION
CHANCES INCREASING TOWARD WEEKS END.
TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE NORMAL FOR THIS
PERIOD.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL TODAY WITH TEMPO IFR
CONDITIONS IN SHRA/TSRA UNTIL AROUND 00Z. IFR CONDITIONS AGAIN
POSSIBLE LATE TONIGHT AND EARLY SATURDAY MORNING AS LOW CLOUDS
FORM MAINLY BETWEEN 08Z-13Z.
&&
.MARINE...
SW WINDS WILL DOMINATE INTO EARLY NEXT WEEK AS COLD
FRONT STALLS JUST NORTH OF THE AREA. EXCEPTION WILL BE AFTERNOON
SEABREEZES NEAR THE COAST EACH DAY. NOCTURAL WINDS SURGES WILL
LIKELY PRODUCE SCEC CONDITIONS.
RIP CURRENTS: LOW RISK THROUGH THE WEEKEND WITH OFFSHORE WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 73 92 73 91 / 40 70 50 40
SSI 75 86 76 89 / 30 60 50 50
JAX 74 88 74 88 / 30 60 50 60
SGJ 73 86 74 86 / 40 60 50 60
GNV 72 87 73 86 / 40 50 50 60
OCF 72 87 73 87 / 40 50 60 60
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
STRUBLE/ZIBURA
AREA FORECAST DISCUSSION
NWS LINCOLN IL
317 PM CDT FRI JUL 31 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 315 PM CDT FRI JUL 31 2015
19Z/2PM SURFACE ANALYSIS SHOWS WEAK COLD FRONT SETTLING INTO CENTRAL
ILLINOIS...EXTENDING FROM NEAR RANTOUL TO JUST SOUTH OF QUINCY.
MINIMAL CONVERGENCE ALONG THE FRONT AND AN OVERALL LACK OF DEEP
LAYER MOISTURE HAS LARGELY PREVENTED CONVECTION. THE EXCEPTION HAS
BEEN FURTHER NORTHEAST ACROSS NORTHERN INDIANA WHERE A FEW CLUSTERS
OF THUNDERSTORMS HAVE DEVELOPED. HRRR CONTINUES TO OVER-EMPHASIZE
DEWPOINT POOLING ALONG THE FRONT AND PRODUCES NUMEROUS THUNDERSTORMS
WITH ITS 1 AND 2-HOUR FORECAST. MEANWHILE...THE RAPID REFRESH HAS
CONSISTENTLY PRESENTED A MORE REALISTIC SCENARIO...SUGGESTING ONLY
ISOLATED STORMS MAINLY ACROSS THE E/NE KILX CWA OVER THE NEXT 2-4
HOURS. GIVEN THIS IS THE LOCATION WHERE CU-FIELD IS CURRENTLY MOST
PRONOUNCED...WILL CONTINUE TO FOLLOW THIS SOLUTION CLOSELY. AS A
RESULT...WILL CARRY SLIGHT CHANCE POPS ALONG/NORTHEAST OF A
CHAMPAIGN TO MARSHALL LINE THROUGH THE AFTERNOON. ANY ISOLATED
CONVECTION THAT DEVELOPS WILL QUICKLY DISSIPATE TOWARD
SUNSET...FOLLOWED BY MOSTLY CLEAR AND DRY CONDITIONS TONIGHT.
SLIGHTLY DRIER AIRMASS WILL TRICKLE IN FROM THE NORTHWEST ONCE THE
FRONT PASSES...WITH OVERNIGHT LOW TEMPERATURES DROPPING INTO THE
LOWER TO MIDDLE 60S.
&&
.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 315 PM CDT FRI JUL 31 2015
OVERALL A FAIRLY PERSISTENT WNW FLOW PATTERN WILL REMAIN ACROSS IL
AND MUCH OF THE MIDWEST THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK. QUITE A BIT OF MODEL UNCERTAINTY REGARDING A BREAKDOWN OF THE
WESTERN RIDGE AND DEEPENING OF THE EASTERN TROUGH FOR THE MIDDLE OF
NEXT WEEK.
IN THE NEAR TERM...VERY WARM AND INCREASINGLY HUMID CONDITIONS WILL
BE ON TAP FOR CENTRAL AND EASTERN IL SATURDAY. AN ADVANCING WARM
FRONT AND A CLUSTER OF CONVECTION FROM IOWA/NEBRASKA IS EXPECTED TO
APPROACH AREAS WEST OF THE IL RIVER VALLEY LATE SATURDAY NIGHT AND
INTO SUNDAY MORNING. THE REMNANTS OF THE EARLY MORNING T-STORMS ARE
THEN EXPECTED TO SPREAD ACROSS MOST OF CENTRAL AND EASTERN IL SUNDAY
MORNING AND EARLY AFTERNOON. RESIDUAL BOUNDARIES FROM THIS
CONVECTION SHOULD RESULT IN REDEVELOPMENT OF T-STORMS SUNDAY
AFTERNOON AND INTO THE EVENING...ESPECIALLY ALONG AND NORTH OF I-74.
SOME OF THE STORMS LATER IN THE DAY SUNDAY COULD BE STRONG...MAINLY
DUE TO MODERATE LEVELS OF WIND SHEAR AND INSTABILITY.
MOST OF THE FORECAST AREA WILL BE IN THE WARM SECTOR OF AN ADVANCING
FRONTAL BOUNDARY...YIELDING VERY WARM AND SOMEWHAT HUMID CONDITIONS
MONDAY. THE AFOREMENTIONED FRONT IS EXPECTED TO SLOWLY MOVE INTO
CENTRAL ILLINOIS MONDAY NIGHT AND THEN REMAIN NEARLY STATIONARY FOR
MUCH OF THE WEEK. THIS SHOULD RESULT IN A RATHER UNSETTLED WEATHER
PATTERN WITH THE POTENTIAL FOR SEVERAL PERIODS OF RAIN FROM LATE
MONDAY...ON AND OFF...THROUGH THE END OF THE WEEK.
THE UNCERTAINTY IN THE MODELS REVOLVES AROUND THE DETAILS OF
POSSIBLE SHORTWAVE ENERGY BREAKING THROUGH THE WESTERN U.S. RIDGE
AND INTERACTING WITH THE FRONT. THE GFS IS A BIT MORE AGGRESSIVE WITH
THIS THAN THE EUROPEAN MODEL. HOWEVER...THE EUROPEAN NOT ONLY
UNDERPLAYS THE AFFECTS OF THIS BUT KEEPS THE SURFACE FRONT FARTHER
NORTH. UNTIL THE DETAILS ARE WORKED OUT IT IS HARD TO PIN DOWN
WHERE A THREAT OF PERSISTENT...POSSIBLY HEAVY RAIN MAY SET UP THE
MIDDLE OF NEXT WEEK. THUS...WILL NOT MAKE TOO MANY MAJOR CHANGES
TO THE FORECAST AND KEEP CHANCE POPS FOR THUNDERSTORMS ACROSS A
LARGE PART OF THE FORECAST AREA.
THE ONE THING THE MODELS DO AGREE ON IS THAT WITH THE PERIODS OF
CONVECTION AND RESIDUAL CLOUD COVER...TEMPERATURES SHOULD BE BELOW
SEASONAL NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1255 PM CDT FRI JUL 31 2015
WEAK COLD FRONT CONTINUES TO SAG SOUTHWARD INTO NORTH-CENTRAL
ILLINOIS EARLY THIS AFTERNOON. CU-FIELD REMAINS LARGELY ABSENT
ALONG THE BOUNDARY THUS FAR...EXCEPT ACROSS NORTHERN INDIANA INTO
NORTHEAST ILLINOIS. THIS CLOUD TREND FITS VERY WELL WITH THE RAPID
REFRESH...WHICH SHOWS WIDELY SCATTERED CONVECTION DEVELOPING
ACROSS THIS AREA OVER THE NEXT COUPLE OF HOURS...WHILE KEEPING THE
REMAINDER OF THE FRONTAL BOUNDARY TOTALLY DRY. AS A RESULT...WILL
ONLY MENTION VCTS AT KCMI BETWEEN 18Z AND 22Z. FEW-SCT DIURNAL
CLOUDS ALONG/AHEAD OF THE FRONT WILL QUICKLY DISSIPATE TOWARD
SUNSET...WITH CLEAR SKIES EXPECTED TONIGHT THROUGH SATURDAY
MORNING. WINDS WILL INITIALLY BE FROM THE NORTHWEST GUSTING TO
BETWEEN 15 AND 18KT THIS AFTERNOON...THEN WILL BECOME WESTERLY AT
LESS THAN 5KT TONIGHT.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARNES
LONG TERM...MILLER
AVIATION...BARNES
AREA FORECAST DISCUSSION
NWS TOPEKA KS
558 PM CDT FRI JUL 31 2015
...UPDATE TO NEAR TERM CONVECTIVE FORECAST...
.UPDATE...
ISSUED AT 551 PM CDT FRI JUL 31 2015
MADE VERY LITTLE CHANGE TO THE ONGOING FORECAST. WHILE
THUNDERSTORMS ARE ONGOING IN NEBRASKA WITH A STRONG SOUTHERLY
COMPONENT TO THE MOTION, INSTABILITY DECREASES SHARPLY WITH
APPROACH TOWARD THE KANSAS BORDER. THE MAIN INSTABILITY AXIS SEEMS
TO RUN FROM SOUTHEAST NEBRASKA INTO NORTHWEST MISSOURI SO COULD
SEE SOME THUNDERSTORM ACTIVITY CLIP NORTHERN AND PARTICULARLY
NORTHEAST PARTS OF THE FORECAST AREA THIS EVENING. THE HRRR IS
VERY AGGRESSIVE WITH THUNDERSTORM COVERAGE (AS IT CAN BE AT TIMES
OF WEAK FORCING) AND BELIEVE IT IS LIKELY OVERDONE WITH THE
OVERALL COVERAGE AND PERSISTENCE OF THE STORM ACTIVITY INTO
KANSAS. AT THE SAME TIME...A STRONG COLD POOL HAS DEVELOPED FROM
NORTHERN STORMS AND WILL LIKELY WEAKEN AS IT MOVES INTO NORTHERN
KS...POSSIBLY STRONG ENOUGH TO KICK OFF ANOTHER STORM OR TWO.
BOTTOM LINE...STORM CHANCES THIS EVENING REMAIN LOW AND FOCUSED
OVER NORTHERN AND PERHAPS NORTHEAST KANSAS. IF ANYTHING DEVELOPS
INTO THE AREA THERE IS A VERY SMALL CHANCE FOR IT TO PRODUCE
MARGINALLY SEVERE HAIL OR LOCALLY DAMAGING WINDS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 335 PM CDT FRI JUL 31 2015
THUNDERSTORMS WERE DEVELOPING IN THE MOISTURE AND INSTABILITY AXIS
ALONG AN OLD OUTFLOW BOUNDARY IN NORTHERN AND EASTERN NEBRASKA THIS
AFTERNOON AT 20Z. FORECAST SHEAR THIS EVENING ACROSS NORTHEAST
KANSAS IS MARGINAL IN THE 25 TO 30 KT RANGE WITH MLCAPE FORECAST IN
THE 1000-2000 J/KG RANGE. CONVECTION IN NEBRASKA IF IT HOLDS
TOGETHER WOULD TRACK SOUTHEAST INTO NORTHEAST KANSAS THIS EVENING.
WITH LACK OF UPPER FORCING AND THE FOCUS FOR INSTABILITY AND
MOISTURE NORTH IN NEBRASKA WILL KEEP SMALL CHANCES OF PRECIPITATION
ACROSS THE NORTHERN COUNTIES FOR THE EVENING HOURS. LOWS SHOULD FALL
INTO THE UPPER 60S TO LOW 70S.
SATURDAY...MODELS DEVELOP SCATTERED SHOWERS AND THUNDERSTORMS DURING
THE LATE AFTERNOON ACROSS NEBRASKA AND THEN SOUTHEAST INTO SOUTHWEST
IOWA, NORTHWEST MISSOURI AND FAR NORTHEAST KANSAS AHEAD OF A WEAK
SHORTWAVE TROUGH. WILL KEEP A SMALL CHANCE OF THUNDERSTORMS NEAR THE
NEBRASKA BORDER IN THE LATE AFTERNOON HOURS. HIGHS A LITTLE WARMER
IN THE LOW TO MID 90S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 PM CDT FRI JUL 31 2015
SATURDAY NIGHT T0 MONDAY...
ANOTHER WAVE IS FCST TO SLIDE SE ACROSS THE REGION SAT NIGHT WHICH
SHOULD BRING ANOTHER ROUND OF STORMS TO PARTS OF NE/IA/MO AND
PERHAPS CLIPPING FAR NORTHEAST KS WITHIN THE LOW LEVEL WAA REGIME.
STRONGEST FORCING SHOULD REMAIN NE OF THE AREA SO WILL ONLY KEEP
LOWER CHC POPS FOR SAT NIGHT. BY SUNDAY SFC LOW PRESSURE WILL SLIDE
INTO WI WITH A COLD FRONT FCST TO SAG INTO THE STATE BY PEAK
HEATING. WILL LEAVE SLIGHT CHCS IN THE FCST FOR THE NORTHERN HALF
NEAR THE FRONT ON SUNDAY FOR RISK OF ISOLATED THUNDER IN THE
EVENING. BETTER CHANCES FOR STORMS WOULD APPEAR TO ARRIVE BY MONDAY
NIGHT AND BEYOND AS MID/UPPER WAVES MOVE ACROSS THE ROCKIES INTO THE
PLAINS AND INTERACT WITH A FRONTAL BOUNDARY IN THE VICINITY.
MONDAY NIGHT TO FRIDAY...
UPPER LEVEL NORTHWEST FLOW CONTINUES AS A SHORTWAVE MOVES OVER
NORTHERN KANSAS MONDAY NIGHT TO TUESDAY MORNING. THIS SHORTWAVE IS
PROGGED TO EXIT THE AREA BY TUESDAY AFTERNOON, BEFORE ANOTHER CHANCE
FOR PRECIPITATION IS SEEN TUESDAY TO WEDNESDAY MORNING ASSOCIATED
WITH ANOTHER PASSING SHORTWAVE. WITH NORTHWEST FLOW CONTINUING
THROUGH THE END OF THE PERIOD, SLIGHT CHANCES FOR STORMS REMAIN
UNTIL FRIDAY. HIGHS REMAIN IN THE LOW TO MID 90S THROUGH THURSDAY,
WITH A SLIGHT COOL DOWN FRIDAY DUE TO A SURFACE FRONTAL PASSAGE.
LOWS STAY MILD IN THE UPPER 60S/LOW 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1240 PM CDT FRI JUL 31 2015
VFR TO CONTINUE THROUGH THE PERIOD. SHOULD BE MIXED ENOUGH TO
PREVENT VISIBILITY RESTRICTIONS LATE TONIGHT. CONVECTION IS
EXPECTED TO REMAIN TO THE NORTH AND EAST OF THE TERMINALS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...53
LONG TERM...HELLER/OMITT
AVIATION...53
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
339 PM CDT FRI JUL 31 2015
...UPDATED LONG TERM SECTION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
THE SUMMER SUBTROPICAL RIDGE WAS CENTERED OVER ITS CLIMATOLOGICAL
POSITION FROM THE SOUTHERN ROCKIES INTO TEXAS TODAY. IN THE UPPER
TROPOSPHERE, WEST NORTHWEST FLOW EXTENDED FROM THE NORTHERN ROCKIES
THROUGH THE UPPER MISSISSIPPI VALLEY. WESTERN KANSAS WAS ON THE
SOUTH EDGE OF THE WESTERLIES AT 250MB. THE MESOSCALE CONVECTIVE
SYSTEM (MCS) THAT AFFECTED EXTREME SOUTHWEST KANSAS OVERNIGHT AND
THIS MORNING WAS DECREASING IN AREAL EXTENT AND MOVING VERY SLOWLY
TO THE EAST-SOUTHEAST...FOLLOWING ROUGHLY THE 3-8KM AGL MEAN FLOW
VECTOR (JUST NORTH OF THE CENTER OF THE MEAN ANTICYCLONE IN THIS
LAYER OVER WEST TEXAS). A COUPLE OF MESOSCALE CONVECTIVE VORTICITY
MAXIMAS COULD BE IDENTIFIED THROUGH VISIBLE SATELLITE AND EVEN THE
HOURLY RAP ANALYSIS FROM NEAR TUCUMCARI NEW MEXICO TO NEAR
SPRINGFIELD COLORADO. IT WOULD APPEAR AS OF THESE MESOSCALE FEATURES
WERE ACTUALLY HELPING TO MAINTAIN THE SMALL MCS THROUGH THE EARLY
AFTERNOON HOURS AS THE LEADING EDGE OF IT WAS MOVING INTO THE FAR
EASTERN OK-TX PANHANDLES. THE VERY NORTHERN EXTENT OF THIS MCS
EXTENDED INTO MORTON AND SEWARD COUNTIES, WHICH WAS HAVING AN IMPACT
ON SURFACE TEMPERATURES (COOLER THAN FORECAST IN THIS AREA). WE HAVE
ADJUSTED THE DAYTIME TEMPERATURES DOWNWARD ACROSS FAR SOUTHWEST
KANSAS AS A RESULT. ELSEWHERE...ESPECIALLY ACROSS WEST CENTRAL AND
CENTRAL KANSAS NORTH OF HIGHWAY 96, TEMPERATURES SHOULD TOP OUT IN
THE LOWER TO MID 90S.
AS WE GO IN TO TONIGHT...ANOTHER SMALL MCS SHOULD EVOLVE THROUGH THE
LATE NIGHT HOURS FROM CONVECTION ACROSS THE HIGHER TERRAIN OF THE
RATON MESA REGION. THIS CONVECTION SHOULD FOLLOW THE SAME GENERAL
TRACK AS THIS MORNINGS MCS, SO WE WILL KEEP THE BEST POPS ACROSS FAR
SOUTHWEST KANSAS AGAIN IN THE 40-50 PERCENT RANGE. THE BULK OF LATE
TONIGHT/TOMORROWS MCS SHOULD REMAIN ACROSS THE PANHANDLES REGION. IT
SHOULD BE CLOSE TO A RINSE AND REPEAT TYPE OF DEAL TOMORROW WITH A
SLOWLY DECAYING MCS SOMEWHERE JUST SOUTH OF OUR FORECAST AREA (OR
PERHAPS CLIPPING MORTON-SEWARD-MEADE) WITH WARMEST TEMPERATURES UP
NORTH ALONG I-70 (MID 90S) AND COOLEST TEMPERATURES ALONG THE OK
BORDER (LOWER-MID 80S, IF EVEN THAT WARM).
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 PM CDT FRI JUL 31 2015
THE BEST CHANCE FOR THE NEXT ORGANIZED PRECIPITATION EVENT WILL BE
MONDAY NIGHT INTO TUESDAY. THE GLOBAL SPECTRAL MODELS CONTINUE TO
SHOW AN INTERACTION BETWEEN MONSOON PERTURBATIONS MOVING NORTHWARD
THROUGH THE DESERT SOUTHWEST...AND AN INCOMING SUBTROPICAL PACIFIC
JET MOVING INTO THE INTERMOUNTAIN WEST REGION. THIS WILL ACT TO
SHIFT THE MONSOON CIRCULATION NORTHEASTWARD SOME...ENHANCING THE
PRECIPITATION POTENTIAL FOR SOUTHWEST KANSAS. IT VERY WELL COULD BE
JUST ONE BIG MCS WE SEE OUT OF THIS EVENT, IN WHICH CASE IF THE
ECMWF HAS A HANDLE ON THINGS, WOULD BE MONDAY NIGHT. THIS IS WHEN
THE HIGHEST POPS ARE IN THE GRIDS FOR THE ENTIRE REGION. ONCE THAT
WAVE EXITS THE CENTRAL PLAINS...THE SUMMER SUBTROPICAL RIDGE WILL
BUILD BACK IN, HOWEVER DEEP TROPOSPHERIC MONSOON MOISTURE WILL BE
FAIRLY SCANT AND IT WILL NEED TO BE RECHARGED AGAIN BY WAY OF LATE
DAY HIGH TERRAIN THUNDERSTORMS. THE LATEST ECMWF FAVORS RIDGE-
BUILDING INTO THE NORTHERN PLAINS WHICH WOULD RESULT IN A WARMING OF
THE LOWER TROPOSPHERE AND SURFACE TEMPERATURES REACHING OR EXCEEDING
THE UPPER 90S BY MID TO LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
FAIRLY QUIET AVIATION WEATHER IS EXPECTED THROUGH TONIGHT AND EARLY
SATURDAY WITH A WEAK PRESSURE GRADIENT RESULTING IN THE CONTINUATION
OF WINDS BELOW 12 KNOTS FOR THE MOST PART. CONVECTIVE ACTIVITY IS
EXPECTED TO REMAIN SOUTH OF THE GCK AND DDC TERMINALS, SO WE WILL
NOT BE FORECASTING ANY THUNDERSTORMS AT THIS TIME. VFR CONDITIONS
ARE EXPECTED TO PREVAIL, HOWEVER THERE COULD BE A BRIEF PERIOD OF
MVFR CEILINGS IN THE EARLY MORNING HOURS AT GCK AND DDC AS
THUNDERSTORM ACTIVITY TO THE SOUTH COULD HAVE SOME IMPACT SIMILAR TO
WHAT WE SAW EARLIER THIS MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 87 67 93 / 10 10 10 10
GCK 67 87 67 92 / 10 10 10 10
EHA 66 85 67 92 / 20 40 20 10
LBL 68 83 68 92 / 20 30 20 10
HYS 67 93 67 95 / 10 10 10 10
P28 71 90 70 94 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...UMSCHEID
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS GOODLAND KS
200 PM MDT FRI JUL 31 2015
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 141 PM MDT FRI JUL 31 2015
PERSISTENT UPPER LEVEL RIDGE CONTINUES TO DOMINATE PATTERN ACROSS
WESTERN US THROUGH THE SOUTHERN PLAINS...WITH NW FLOW ACROSS THE
NORTHERN PLAINS. WV IMAGERY SHOWS MONSOONAL MOISTURE PLUME EXTENDING
FROM THE BAJA PENINSULA ACROSS THE FOUR CORNER AND INTO THE HIGH
PLAINS WITH SEVERAL WEAK SHORTWAVE TROUGHS ROTATING AROUND RIDGE
INTO THE SOUTHERN PLAINS AND THROUGH THE NW FLOW ALONG THE MISSOURI
RIVER VALLEY. AT THE SURFACE...MEAN SURFACE TROUGH EXTENDS ACROSS
NORTHERN COLORADO INTO CENTRAL NEBRASKA...WITH WEAK FLOW AND A
SECONDARY WEAK TROUGH AXIS/SURFACE CONVERGENT ZONE ALONG THE KS CO
BORDER EXTENDING SOUTH INTO SOUTH CENTRAL KS.
MODELS CONTINUE TO UNDERESTIMATE TDS WITH 60-70F TD VALUES REPORTED
MOST OF THE DAY...FINALLY BEGINNING TO FALL IN OUR NW. RESULT IS
MUCH HIGHER CAPE VALUES THAN PREVIOUSLY ADVERTISED WITH RAP ANALYSIS
SHOWS A SHARP GRADIENT OF SB CAPE FROM 250 J/KG IN NORTHEAST
COLORADO TO 3000 J/KG OVER OUR SOUTHERN CWA. CONSIDERING THE MOIST
BL LAYER AND FAVORABLE CAPE PROFILES OVER MOST OF THE AREA IT WON`T
TAKE MUCH FOR THUNDERSTORMS TO DEVELOP. WITH ONLY WEAK HEIGHT FALLS
THIS AFTERNOON/TONIGHT AND MODELS SHOWING ALMOST NO ACTIVITY
INITIATING OVER OUR CA (DESPITE LOW CINH)...I AM FAVORING ISOLATED
THUNDERSTORM MENTION FOR NOW. AS WITH LAST NIGHT...VERY LITTLE STORM
MOTION (0-6KM 0-5KT ACROSS MUCH OF THE AREA) WILL RESULT IN
POTENTIAL FOR FLASH FLOODING. IF CELL MERGERS OCCUR AND ARE ABLE TO
DEVELOP A COLD POOL OR OUTFLOW WE COULD SEE BETTER COVERAGE. LOW
CONFIDENCE AT THIS POINT.
SATURDAY...PATTERN WILL BE VERY SIMILAR AS TODAY WITH SEASONAL HIGHS
(UPPER 80S-MID 90S). GUIDANCE ACTUALLY INDICATING SUBSIDENCE WILL BE
IN PLACE...SO WHILE HIGH CAPE VALUES/DECENT MOISTURE PROFILES WILL
LIKELY SET UP OVER THE CWA ONCE AGAIN CONFIDENCE IN ANY INITIATION
IS EVEN LOWER THAN TODAY. I DECIDED TO KEEP THUNDERSTORM MENTION
OUT FOR NOW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 200 PM MDT FRI JUL 31 2015
FOR THE EXTENDED PERIOD...THE LATTER PORTION OF THE WEEKEND RIGHT
THROUGH MUCH OF NEXT WEEK...THE ENTIRE TRI STATE REGION WILL SEE
ABOVE NORMAL TEMPERATURES BROUGHT ABOUT BY A STRONG AMPLIFIED
500/700 MB RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...THAT
SHIFTS EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY. LATEST
MODEL RUNS STILL SHOW 850 MB TEMPS RANGING FROM +29C TO ALMOST
+35C...UNDER WNW UPPER FLOW. THIS IS GOING TO GIVE THE AREA DAYTIME
HIGHS WELL INTO THE 90S...WARMEST ON WEDNESDAY WHEN UPPER RIDGE AXIS
SETTLES OVER THE REGION AND COULD GIVE MID TO UPPER 90S TO THE AREA.
COOLER AIR COULD ARRIVE DURING THE DAY FRIDAY WITH SURFACE RIDGE
BUILDING SOUTH THRU THE PLAINS AFTER FRONTAL PASSAGE LATE THURSDAY
NIGHT.
DESPITE STRONG RIDGING OVER THE REGION OVER THE NEXT WEEK...SEVERAL
SHORTWAVES ARE EXPECTED TO TRAVERSE OVER THE NORTHERN HALF OF THE
RIDGE...BRINGING THE CHANCE FOR SHOWERS/THUNDERSTORMS. THIS ACTIVITY
THOUGH WILL SPARE THE FORECAST AREA FOR THIS UPCOMING WEEKEND...ONLY
TO BEGIN WITH A STRONG TROUGH LATE MONDAY INTO TUESDAY AND THEN
SUBSEQUENT SYSTEMS. BEST CHANCES FOR PRECIP THOUGH AS WEEK
PROGRESSES WILL BEGIN TO SHIFT MORE EASTWARD OVER THE CWA...DUE TO
MOVEMENT OF UPPER RIDGE WHICH WILL AFFECT PLACEMENT OF EACH LATTER
SHORTWAVE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1119 AM MDT FRI JUL 31 2015
VFR CONDITIONS CURRENTLY FORECAST THROUGH THE TAF PERIOD AT BOTH
KGLD AND KMCK. LOW CONFIDENCE OVERALL IN AVIATION FORECAST AS A
RESULT OF POOR MODEL PERFORMANCE REGARDING LOW LEVEL MOISTURE
OVER BOTH TERMINALS. I COULD SEE PATCHY FOG DEVELOPING AGAIN BY
SUNRISE SATURDAY IF HIGHER DEWPOINTS CONTINUE TO LINGER...HOWEVER
AT THIS POINT THERE IS NO MODEL SUPPORT SO I LEFT MENTION OUT.
OTHER AVIATION CONCERN WILL BE POTENTIAL FOR THUNDERSTORMS.
CURRENTLY ACTIVITY IS EXPECTED TO BE ISOLATED WITH BETTER CHANCES
IN EASTERN COLORADO...SO WILL LEAVE OUT OF TAFS DURING THIS
UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
141 PM MDT FRI JUL 31 2015
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 141 PM MDT FRI JUL 31 2015
PERSISTENT UPPER LEVEL RIDGE CONTINUES TO DOMINATE PATTERN ACROSS
WESTERN US THROUGH THE SOUTHERN PLAINS...WITH NW FLOW ACROSS THE
NORTHERN PLAINS. WV IMAGERY SHOWS MONSOONAL MOISTURE PLUME EXTENDING
FROM THE BAJA PENINSULA ACROSS THE FOUR CORNER AND INTO THE HIGH
PLAINS WITH SEVERAL WEAK SHORTWAVE TROUGHS ROTATING AROUND RIDGE
INTO THE SOUTHERN PLAINS AND THROUGH THE NW FLOW ALONG THE MISSOURI
RIVER VALLEY. AT THE SURFACE...MEAN SURFACE TROUGH EXTENDS ACROSS
NORTHERN COLORADO INTO CENTRAL NEBRASKA...WITH WEAK FLOW AND A
SECONDARY WEAK TROUGH AXIS/SURFACE CONVERGENT ZONE ALONG THE KS CO
BORDER EXTENDING SOUTH INTO SOUTH CENTRAL KS.
MODELS CONTINUE TO UNDERESTIMATE TDS WITH 60-70F TD VALUES REPORTED
MOST OF THE DAY...FINALLY BEGINNING TO FALL IN OUR NW. RESULT IS
MUCH HIGHER CAPE VALUES THAN PREVIOUSLY ADVERTISED WITH RAP ANALYSIS
SHOWS A SHARP GRADIENT OF SB CAPE FROM 250 J/KG IN NORTHEAST
COLORADO TO 3000 J/KG OVER OUR SOUTHERN CWA. CONSIDERING THE MOIST
BL LAYER AND FAVORABLE CAPE PROFILES OVER MOST OF THE AREA IT WON`T
TAKE MUCH FOR THUNDERSTORMS TO DEVELOP. WITH ONLY WEAK HEIGHT FALLS
THIS AFTERNOON/TONIGHT AND MODELS SHOWING ALMOST NO ACTIVITY
INITIATING OVER OUR CA (DESPITE LOW CINH)...I AM FAVORING ISOLATED
THUNDERSTORM MENTION FOR NOW. AS WITH LAST NIGHT...VERY LITTLE STORM
MOTION (0-6KM 0-5KT ACROSS MUCH OF THE AREA) WILL RESULT IN
POTENTIAL FOR FLASH FLOODING. IF CELL MERGERS OCCUR AND ARE ABLE TO
DEVELOP A COLD POOL OR OUTFLOW WE COULD SEE BETTER COVERAGE. LOW
CONFIDENCE AT THIS POINT.
SATURDAY...PATTERN WILL BE VERY SIMILAR AS TODAY WITH SEASONAL HIGHS
(UPPER 80S-MID 90S). GUIDANCE ACTUALLY INDICATING SUBSIDENCE WILL BE
IN PLACE...SO WHILE HIGH CAPE VALUES/DECENT MOISTURE PROFILES WILL
LIKELY SET UP OVER THE CWA ONCE AGAIN CONFIDENCE IN ANY INITIATION
IS EVEN LOWER THAN TODAY. I DECIDED TO KEEP THUNDERSTORM MENTION
OUT FOR NOW.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1119 AM MDT FRI JUL 31 2015
VFR CONDITIONS CURRENTLY FORECAST THROUGH THE TAF PERIOD AT BOTH
KGLD AND KMCK. LOW CONFIDENCE OVERALL IN AVIATION FORECAST AS A
RESULT OF POOR MODEL PERFORMANCE REGARDING LOW LEVEL MOISTURE
OVER BOTH TERMINALS. I COULD SEE PATCHY FOG DEVELOPING AGAIN BY
SUNRISE SATURDAY IF HIGHER DEWPOINTS CONTINUE TO LINGER...HOWEVER
AT THIS POINT THERE IS NO MODEL SUPPORT SO I LEFT MENTION OUT.
OTHER AVIATION CONCERN WILL BE POTENTIAL FOR THUNDERSTORMS.
CURRENTLY ACTIVITY IS EXPECTED TO BE ISOLATED WITH BETTER CHANCES
IN EASTERN COLORADO...SO WILL LEAVE OUT OF TAFS DURING THIS
UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1228 PM CDT FRI JUL 31 2015
...UPDATED SHORT TERM AND AVIATION SECTIONS...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
THE SUMMER SUBTROPICAL RIDGE WAS CENTERED OVER ITS CLIMATOLOGICAL
POSITION FROM THE SOUTHERN ROCKIES INTO TEXAS TODAY. IN THE UPPER
TROPOSPHERE, WEST NORTHWEST FLOW EXTENDED FROM THE NORTHERN ROCKIES
THROUGH THE UPPER MISSISSIPPI VALLEY. WESTERN KANSAS WAS ON THE
SOUTH EDGE OF THE WESTERLIES AT 250MB. THE MESOSCALE CONVECTIVE
SYSTEM (MCS) THAT AFFECTED EXTREME SOUTHWEST KANSAS OVERNIGHT AND
THIS MORNING WAS DECREASING IN AREAL EXTENT AND MOVING VERY SLOWLY
TO THE EAST-SOUTHEAST...FOLLOWING ROUGHLY THE 3-8KM AGL MEAN FLOW
VECTOR (JUST NORTH OF THE CENTER OF THE MEAN ANTICYCLONE IN THIS
LAYER OVER WEST TEXAS). A COUPLE OF MESOSCALE CONVECTIVE VORTICITY
MAXIMAS COULD BE IDENTIFIED THROUGH VISIBLE SATELLITE AND EVEN THE
HOURLY RAP ANALYSIS FROM NEAR TUCUMCARI NEW MEXICO TO NEAR
SPRINGFIELD COLORADO. IT WOULD APPEAR AS OF THESE MESOSCALE FEATURES
WERE ACTUALLY HELPING TO MAINTAIN THE SMALL MCS THROUGH THE EARLY
AFTERNOON HOURS AS THE LEADING EDGE OF IT WAS MOVING INTO THE FAR
EASTERN OK-TX PANHANDLES. THE VERY NORTHERN EXTENT OF THIS MCS
EXTENDED INTO MORTON AND SEWARD COUNTIES, WHICH WAS HAVING AN IMPACT
ON SURFACE TEMPERATURES (COOLER THAN FORECAST IN THIS AREA). WE HAVE
ADJUSTED THE DAYTIME TEMPERATURES DOWNWARD ACROSS FAR SOUTHWEST
KANSAS AS A RESULT. ELSEWHERE...ESPECIALLY ACROSS WEST CENTRAL AND
CENTRAL KANSAS NORTH OF HIGHWAY 96, TEMPERATURES SHOULD TOP OUT IN
THE LOWER TO MID 90S.
AS WE GO IN TO TONIGHT...ANOTHER SMALL MCS SHOULD EVOLVE THROUGH THE
LATE NIGHT HOURS FROM CONVECTION ACROSS THE HIGHER TERRAIN OF THE
RATON MESA REGION. THIS CONVECTION SHOULD FOLLOW THE SAME GENERAL
TRACK AS THIS MORNINGS MCS, SO WE WILL KEEP THE BEST POPS ACROSS FAR
SOUTHWEST KANSAS AGAIN IN THE 40-50 PERCENT RANGE. THE BULK OF LATE
TONIGHT/TOMORROWS MCS SHOULD REMAIN ACROSS THE PANHANDLES REGION. IT
SHOULD BE CLOSE TO A RINSE AND REPEAT TYPE OF DEAL TOMORROW WITH A
SLOWLY DECAYING MCS SOMEWHERE JUST SOUTH OF OUR FORECAST AREA (OR
PERHAPS CLIPPING MORTON-SEWARD-MEADE) WITH WARMEST TEMPERATURES UP
NORTH ALONG I-70 (MID 90S) AND COOLEST TEMPERATURES ALONG THE OK
BORDER (LOWER-MID 80S, IF EVEN THAT WARM).
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 200 AM CDT FRI JUL 31 2015
SATURDAY WILL BE SOMEWHAT INTERESTING. SYNOPTICALLY THERE ISN`T MUCH
FOCUS FOR THUNDERSTORM DEVELOPMENT. ARW AND NMM ARE PRECIPITATION FREE.
THE ECMWF, INTERESTINGLY ENOUGH, IS WETTER AS IT HAS STRONGER LOW LEVEL
LIFT. AT THIS POINT, WILL KEEP THE FORECAST DRY AND LET FUTURE SHIFTS
ADJUST AS NEEDED. IF THERE IS CONVECTION, THEN HIGH TEMPERATURES COULD
BE TRICKY AS SOME COOLER AREAS WILL RESULT. SUNDAY SHOULD BE FAIRLY
DRY AS SHORTWAVE RIDGING STARTS TO NOSE IN FROM THE WEST. HIGHS WILL
MODERATE A FEW DEGREES AND WILL BE AROUND 90F. FOR THE REST, STUCK WITH
SUPERBLEND POPS AND TEMPS AS THE GRIDS LOOK REASONABLE. THERE WILL BE
A CHANCE FOR STORMS AGAIN AS A FEW SYNOPTIC WAVES MOVE ACROSS THE GREAT
PLAINS NEXT WEEK. HIGHS WILL STILL BE ON THE WARM SIDE WITH MILD LOWS...
SUMMER CONTINUES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
FAIRLY QUIET AVIATION WEATHER IS EXPECTED THROUGH TONIGHT AND EARLY
SATURDAY WITH A WEAK PRESSURE GRADIENT RESULTING IN THE CONTINUATION
OF WINDS BELOW 12 KNOTS FOR THE MOST PART. CONVECTIVE ACTIVITY IS
EXPECTED TO REMAIN SOUTH OF THE GCK AND DDC TERMINALS, SO WE WILL
NOT BE FORECASTING ANY THUNDERSTORMS AT THIS TIME. VFR CONDITIONS
ARE EXPECTED TO PREVAIL, HOWEVER THERE COULD BE A BRIEF PERIOD OF
MVFR CEILINGS IN THE EARLY MORNING HOURS AT GCK AND DDC AS
THUNDERSTORM ACTIVITY TO THE SOUTH COULD HAVE SOME IMPACT SIMILAR TO
WHAT WE SAW EARLIER THIS MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 88 68 85 66 / 10 10 10 10
GCK 86 67 86 65 / 10 10 10 10
EHA 78 66 86 64 / 80 40 10 10
LBL 81 68 85 65 / 20 20 10 10
HYS 94 67 89 67 / 10 10 10 10
P28 85 71 84 68 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1119 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
UPPER RIDGE OVER THE GREAT BASIN WILL GRADUALLY BUILD OVER THE
CENTRAL ROCKIES AND BE THE DOMINANT FEATURE OF THE SHORT TERM
PERIOD. AS A RESULT...PRECIPITATION CHANCES WILL BE RATHER LOW AND
TEMPERATURES WILL BE WARMING. THAT BEING SAID...MAY SEE AN ISOLATED
STORM OR TWO THIS AFTERNOON IN NORTHEAST COLORADO AS HINTED AT BY
THE HRRR NEAR A WEAK SURFACE CONVERGENCE LINE. ENVIRONMENT WILL
BE SIMILAR TO YESTERDAY SO CANT TOTALLY RULE OUT A SEVERE STORM
CAPABLE OF PRODUCING STRONG WINDS...BUT THINK COVERAGE WILL BE
VERY LIMITED DUE TO LACK OF UPPER SUPPORT. SOME OF THE HIRES NAM
MEMBERS PAINT A SIMILAR SCENARIO SATURDAY AFTERNOON IN NORTHEAST
COLORADO SO CARRIED SOME LOW POPS. ONCE AGAIN SEVERE PARAMETERS
ARE FAIRLY DECENT SHOULD SOMETHING DEVELOP. PERHAPS THE NEXT BEST
CHANCE FOR THUNDERSTORMS WILL BE SUNDAY AFTERNOON AND EVENING WITH
SOMEWHAT BETTER LOOKING TROUGH COMING OUT OF COLORADO AND TOPPING
THE RIDGE AXIS IN THE CENTRAL PLAINS. HOWEVER NOT ENOUGH
CONFIDENCE AT THIS POINT WITH THE STRONG RIDGE IN PLACE THAT IT
WILL ACTUALLY PLAY OUT THAT WAY SO WILL ONLY CARRY SILENT 10 POPS
OR LESS.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1119 AM MDT FRI JUL 31 2015
VFR CONDITIONS CURRENTLY FORECAST THROUGH THE TAF PERIOD AT BOTH
KGLD AND KMCK. LOW CONFIDENCE OVERALL IN AVIATION FORECAST AS A
RESULT OF POOR MODEL PERFORMANCE REGARDING LOW LEVEL MOISTURE
OVER BOTH TERMINALS. I COULD SEE PATCHY FOG DEVELOPING AGAIN BY
SUNRISE SATURDAY IF HIGHER DEWPOINTS CONTINUE TO LINGER...HOWEVER
AT THIS POINT THERE IS NO MODEL SUPPORT SO I LEFT MENTION OUT.
OTHER AVIATION CONCERN WILL BE POTENTIAL FOR THUNDERSTORMS.
CURRENTLY ACTIVITY IS EXPECTED TO BE ISOLATED WITH BETTER CHANCES
IN EASTERN COLORADO...SO WILL LEAVE OUT OF TAFS DURING THIS
UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...024
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1216 PM CDT FRI JUL 31 2015
.UPDATE...
UPDATED FORECAST AND GRIDS TO LOWER RAIN CHANCES ACROSS SOUTHERN
HALF OF AREA TO 20 PERCENT...AND HRRR WOULD INDICATE THAT MAY BE A
LITTLE HIGH. ADJUSTED HOURLY TEMPERATURES AND DEW POINTS TO FIT
CURRENT TRENDS.
&&
.PREV DISCUSSION... /ISSUED 415 AM CDT FRI JUL 31 2015/
SHORT TERM...
THE HEAT WILL BE ON FOR A SHORT TIME TODAY. BUT A COLD FRONT JUST
TO THE NORTH OF THE AREA WILL SLOWLY MOVE THROUGH TODAY. DEW PTS
WILL BEGIN TO LOWER IN MCB BY SUNRISE AND SHOULD REACH ABOUT 63
DEGREES BY AFTERNOON. DP TEMPS WILL LOWER IN SLIDELL AROUND NOON
AND TO THE SOUTH SHORE SHORTLY AFTER. THIS CONTRAST TO THE DP
TEMPS THAT WE HAVE BEEN UNDER LATELY WILL BE FELT. THIS WILL ALSO
DO TWO THINGS. ONE WILL BE TO KEEP TEMPS NEAR WHAT THEY HAVE BEEN
OR EVEN SLIGHTLY HIGHER. THE SECOND THING WILL BE TO KEEP THE HEAT
INDEX VALUES DOWN. TIMING OF SH/TS HAVE BEEN OFF THE LAST FEW DAYS
AND THAT ALWAYS HAS A MAJOR IMPACT ON TEMPS AND THEREFORE HEAT
INDEX VALUES. BUT TODAY SHOULD NOT BE A TIMING ISSUE AS DRY AIR
WILL BE THE CAUSE OF LOWER HEAT INDICES. THE FRONT WILL MOVE BACK
TO THE NORTH BY SAT NIGHT BRINGING BACK THE MOISTURE AND HIGHER
HEAT INDEX VALUES. THE FRONT SHOULD ALSO KEEP ALL SH/TS ACTIVITY
ALONG AND SOUTH OF IT SO POP GRADIENTS HAVE BEEN SET ACCORDINGLY.
LONG TERM...
SH/TS WILL ONCE AGAIN BE BACK TO THE AREA ONCE THE COLD FRONT
LIFTS NORTH OVER THE WEEKEND. AFTER THE WEEKEND...MOST SH/TS WILL
BE ACTIVATED BY C-BRZ AND OUTFLOW BOUNDARIES.
AVIATION...
VFR CONDITIONS ARE EXPECTED WITH THE MAIN EXCEPTION AT KHUM WHERE
SOME TEMPO MVFR WILL CONTINUE THIS MORNING DUE TO LIGHT FOG.
MAINTAIN VCTS THIS AFTERNOON FOR THE AIRPORTS CLOSER TO THE COAST
WHERE THERE IS A BETTER CHANCE OF CONVECTION. 18
MARINE...
A COLD FRONT IS EXPECTED TO PUSH SOUTH ACROSS THE TIDAL
AND EXTREME NEAR SHORE WATERS TODAY AND STALL. A SLIGHT DECREASE IN
THICKNESS 1000-700MB SHOW A 10 TO 15 METER DROP TODAY. NORTH WINDS
WILL KICK UP TO 10 TO 15 KNOTS ACROSS NEAR SHORE WATERS THIS MORNING
AND AGAIN SATURDAY MORNING. THE STALLED COLD FRONT OVER THE COASTAL
WATERS WILL BEGIN TO LOSE ITS IDENTITY OVER THE WEEKEND. HIGH
PRESSURE WILL BUILD OVER THE EAST GULF AND YIELD A WESTERLY FLOW
OVER THE NORTH CENTRAL GULF EARLY NEXT WEEK. 18
DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER FROM RED
RIVER LANDING TO DONALDSONVILLE.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY
ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 95 68 94 69 / 10 0 0 0
BTR 96 70 95 70 / 10 10 0 0
ASD 92 72 94 70 / 10 10 10 10
MSY 93 78 93 79 / 20 10 10 20
GPT 93 74 92 71 / 10 20 20 20
PQL 94 75 91 70 / 20 20 20 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
138 PM EDT FRI JUL 31 2015
.SYNOPSIS...
A COLD FRONT WILL STALL ALONG THE COAST THROUGH THE WEEKEND. THE
FRONT WEAKENS EARLY NEXT WEEK AS HIGH PRESSURE BUILDS INTO THE
AREA FROM THE ATLANTIC...AND AN INLAND TROUGH DEVELOPS TO THE
WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1235 PM FRIDAY...FRONTAL BOUNDARY REMAINS JUST SOUTH OF THE
NC COAST. HIGH-RESOLUTION MODELS SUCH AS THE HRRR AND RUC INDICATE
A RATHER PROUNOUNCED SEA BREEZE WILL DEVELOP DURING THE LATE
AFTERNOON HOURS. IN CONCERT WITH A DIGGING MID-LEVEL
TROUGH...EXPECT A GOOD COVERAGE OF SHOWERS/THUNDERSTORMS PRIMARY
OVER THE SOUTHERN HALF OF THE AREA AND MAINLY NEAR THE COAST THIS
AFTERNOON INTO THIS EVENING. MODERATE INSTABILITY IS FORECAST
WITH CAPES 1500-2000 J/KG AND LI`S -3 TO -5...BUT A COL IN THE
MID-LEVEL FLOW WILL LEAD TO VERY SLOW MOVEMENT OF ANY ACTIVITY
THAT DEVELOPS WITH POSSIBLE LOCALIZED HEAVY RAINFALL...GIVEN
PRECIPITABLE WATER VALUES OF AROUND 2 INCHES FROM THE 12Z MHX
SOUNDING. ONLY MINOR CHANGES MADE TO CURRENT FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 3 AM FRIDAY...THE STALLED FRONT WILL CONT TO PROVIDE THE
FOCUS FOR SCT CONVECTION ALONG THE SRN TIER TONIGHT WITH MORE
ISOLD PRECIP TO THE N. SLIGHTLY COOLER TEMPS FOR INLAND AREAS
TONIGHT WITH LOWS IN THE UPR 60S TO NEAR 70 COASTAL PLAINS AND
THE LOWER AND MID 70S FOR COASTAL AREAS WITH PARTLY CLOUDY SKIES N
AND MOSTLY CLOUDY SKIES FOR SOUTHERN SXNS WITH BTR PRECIP CHCS.
&&
.LONG TERM /SATURDAY THROUGH FRIDAY/...
AS OF 330 AM FRI...WEAK COLD FRONT WILL STALL NEAT THE COAST
THROUGH THE WEEKEND WHILE BROAD TROUGHING DOMINATES ALOFT.
ATLANTIC HIGH PRESSURE WILL BUILD BACK IN EARLY TO MID NEXT WEEK.
SATURDAY AND SUNDAY...MODELS COMING INTO BETTER AGREEMENT WITH
RESPECT TO SHOWER/STORM CHANCES THIS WEEKEND. THE 31/00Z ECM HAS
CONTINUED TO TREND TOWARDS THE DRIER GFS SOLN. WILL FOLLOW
TRENDS OF DECREASING POPS TO LESS THAN 20 PERCENT FOR THE NORTHERN
AREAS AND 20-30 PERCENT ON THE COAST THROUGH THE WEEKEND. ANY
STORMS THAT DEVELOP COULD PRODUCE HEAVY RAIN PER HIGH LAYER MIX
RATIOS AND COLUMN PWATS AOA 2 INCHES ALONG THE COAST THROUGH THE
WEEKEND. TEMPS WILL BE TYPICALLY HOT WITH HIGHS IN THE LOW 90S
INLAND TO 80S COAST...WITH LOWS IN THE LOW/MID 70S INLAND TO UPR
70S COAST.
MONDAY...SIMILAR SCENARIO TO THE WEEKEND WITH BROAD TROUGHING AND
WASHED OUT FRONTAL BOUNDARY NEAR THE AREA. BEST SHOWER CHANCES
WILL AGAIN BE NEAR OR JUST OFFSHORE EARLY MONDAY...THEN SEA BREEZE
CONVERGENCE DURING THE AFTERNOON MAY PROMOTE SCT/ISO THUNDERSTORMS
FOR THE SECOND HALF OF THE DAY INLAND. STILL HOT AND MUGGY WITH
HIGHS IN THE LOW 90S INLAND TO 80S COAST.
TUESDAY THROUGH THURSDAY...WARMING TEMPS AS THICKNESSES AND TEMPS
BUILD WITH HIGHS CLIMBING INTO THE MID 90S (80S COAST). SOME MODEL
DIFFERENCES CONTINUE MID WEEK AS 31/00Z GFS CONTINUES TROUGHING
ALONG THE EAST COAST AND PUSHES A FRONT THROUGH THE AREA LATE
WED/THU WITH A WAVE DEVELOPING ALONG IT... WHILE THE ECMWF HAS
BERMUDA HIGH AS MAIN FEATURE AND THERMAL TROUGHING INLAND. WILL
TREND WITH WPC/ECMWF AND PREVIOUS FORECAST WITH HIGH OFFSHORE AND
PRED S/SW FLOW ACROSS THE AREA. WILL CONTINUE SC POPS...THINKING
PRIMARILY DIURNALLY DRIVEN AT THIS TIME AND MAINLY AWAY FROM THE
COAST.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 18Z SATURDAY/...
AS OF 130 PM FRIDAY...VFR CONDITIONS THROUGH MUCH OF THE TAF PERIOD.
SHOWERS AND THUNDERSTORMS SHOULD START TO DEVELOP LATER THIS
AFTERNOON ALONG THE SEA BREEZE/STALLED FRONT. THIS ACTIVITY SHOULD
STAY PRIMARILY EAST OF THE TAF SITES. BUT CAN NOT RULE OUT
PRECIPITATION MIGRATING CLOSER TO OAJ/EWN. PRECIPITATION SHOULD
DIMINISH THROUGH THE EVENING HOURS WITH CLOUDS ALSO ERODING THROUGH
THE OVERNIGHT...LINGERING MAINLY ALONG THE COAST. THEREFORE...THIS
MAY PROVIDE A BRIEF OPPORTUNITY FOR FOG TO DEVELOP ESPECIALLY
ACROSS OAJ/ISO DURING THE EARLY MORNING HOURS. FEEL EWN MAY HAVE
TOO MUCH CLOUD COVER STILL IN PLACE TO OBSERVE MUCH FOG. DEW
POINT DEPRESSIONS ACROSS THE NW MIGHT ALSO BE A BIT HIGH.
THEREFORE...HAVE EWN/PGV WITH A BIT HIGHER VSBYS AS COMPARED TO
OAJ/ISO. ANY LOW LEVEL MOISTURE SHOULD MIX OUT BY MID-MORNING
WITH MOSTLY CLEAR SKIES FOR MUCH OF SATURDAY. LIGHT AND VARIABLE
WINDS THROUGH THE TAF PERIOD.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...PRED VFR CONDITIONS EXPECTED THROUGH THE
PERIOD. A FRONT WILL STALL NEAR THE COAST OR JUST OFFSHORE THROUGH
THE WEEKEND. ISOLATED TO SCT SHOWERS/TSTMS SAT THROUGH EARLY NEXT
WEEK...WITH BEST CHANCES AT EWN/OAJ. PATCHY FOG/STRATUS POSSIBLE
EACH NIGHT WITH LIGHT WINDS ESP FOR AREAS THAT RECEIVE RAINFALL.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 1240 PM FRIDAY...STILL GENERALLY NORTHERLY WINDS OVER THE
COASTAL WATERS AND SOUNDS...ALTHOUGH SEEING WINDS VEER TO MORE
SOUTHEAST OVER THE FAR SOUTHERN WATERS. SPEEDS REMAIN LESS THAN
15 KNOTS WITH SEAS OF 3 TO 4 FEET. WILL SEE SOUTHWEST WINDS
DEVELOP WITH A FAIRLY PRONOUNCED SEA BREEZE THIS AFTERNOON OVER
SOUTHERN SECTIONS...WITH LIGHT NORTH WINDS CONTINUING NORTH OF
OCRACOKE. WINDS GRADUALLY BECOME SE TO S TONIGHT 10 KT OR LESS.
WINDS BECOME SW THROUGHOUT TOWARD SAT MORN HIGHEST SRN COASTAL
WATERS. SEAS WILL RANGE 2-4 FT TONIGHT.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...THE COLD FRONT WILL WASH OUT BY SAT WITH
SOUTHERLY FLOW ONCE AGAIN DEVELOPING. GRADIENT TIGHTENS THROUGH
THE DAY SAT WITH INCREASING SSW WINDS 10-15KT CONT INTO SUN. A
PERIOD OF MARGINAL SCA CONDITIONS LIKELY TO DEVELOP SUN
NIGHT...MAINLY SOUTH OF OREGON INLET...WITH WINDS INCREASING TO
15-25KT AND SEAS BUILDING TO 4-7FT. GUSTY SW WINDS EXPECTED TO
CONTINUE INTO TUE...WITH LINGERING 6FT SEAS POSSIBLE INTO TUE
NIGHT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JAC
NEAR TERM...CTC
SHORT TERM...JAC
LONG TERM...CQD/TL
AVIATION...TL/LEP
MARINE...CTC/TL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1239 PM EDT FRI JUL 31 2015
.SYNOPSIS...
A COLD FRONT WILL STALL ALONG THE COAST THROUGH THE WEEKEND. THE
FRONT WEAKENS EARLY NEXT WEEK AS HIGH PRESSURE BUILDS INTO THE
AREA FROM THE ATLANTIC...AND AN INLAND TROUGH DEVELOPS TO THE
WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1235 PM FRIDAY...FRONTAL BOUNDARY REMAINS JUST SOUTH OF THE
NC COAST. HIGH-RESOLUTION MODELS SUCH AS THE HRRR AND RUC INDICATE
A RATHER PROUNOUNCED SEA BREEZE WILL DEVELOP DURING THE LATE
AFTERNOON HOURS. IN CONCERT WITH A DIGGING MID-LEVEL
TROUGH...EXPECT A GOOD COVERAGE OF SHOWERS/THUNDERSTORMS PRIMARY
OVER THE SOUTHERN HALF OF THE AREA AND MAINLY NEAR THE COAST THIS
AFTERNOON INTO THIS EVENING. MODERATE INSTABILITY IS FORECAST
WITH CAPES 1500-2000 J/KG AND LI`S -3 TO -5...BUT A COL IN THE
MID-LEVEL FLOW WILL LEAD TO VERY SLOW MOVEMENT OF ANY ACTIVITY
THAT DEVELOPS WITH POSSIBLE LOCALIZED HEAVY RAINFALL...GIVEN
PRECIPITABLE WATER VALUES OF AROUND 2 INCHES FROM THE 12Z MHX
SOUNDING. ONLY MINOR CHANGES MADE TO CURRENT FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 3 AM FRIDAY...THE STALLED FRONT WILL CONT TO PROVIDE THE
FOCUS FOR SCT CONVECTION ALONG THE SRN TIER TONIGHT WITH MORE
ISOLD PRECIP TO THE N. SLIGHTLY COOLER TEMPS FOR INLAND AREAS
TONIGHT WITH LOWS IN THE UPR 60S TO NEAR 70 COASTAL PLAINS AND
THE LOWER AND MID 70S FOR COASTAL AREAS WITH PARTLY CLOUDY SKIES N
AND MOSTLY CLOUDY SKIES FOR SOUTHERN SXNS WITH BTR PRECIP CHCS.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 330 AM FRI...WEAK COLD FRONT WILL STALL NEAT THE COAST
THROUGH THE WEEKEND WHILE BROAD TROUGHING DOMINATES ALOFT.
ATLANTIC HIGH PRESSURE WILL BUILD BACK IN EARLY TO MID NEXT WEEK.
SATURDAY AND SUNDAY...MODELS COMING INTO BETTER AGREEMENT WITH
RESPECT TO SHOWER/STORM CHANCES THIS WEEKEND. THE 31/00Z ECM HAS
CONTINUED TO TREND TOWARDS THE DRIER GFS SOLN. WILL FOLLOW
TRENDS OF DECREASING POPS TO LESS THAN 20 PERCENT FOR THE NORTHERN
AREAS AND 20-30 PERCENT ON THE COAST THROUGH THE WEEKEND. ANY
STORMS THAT DEVELOP COULD PRODUCE HEAVY RAIN PER HIGH LAYER MIX
RATIOS AND COLUMN PWATS AOA 2 INCHES ALONG THE COAST THROUGH THE
WEEKEND. TEMPS WILL BE TYPICALLY HOT WITH HIGHS IN THE LOW 90S
INLAND TO 80S COAST...WITH LOWS IN THE LOW/MID 70S INLAND TO UPR
70S COAST.
MONDAY...SIMILAR SCENARIO TO THE WEEKEND WITH BROAD TROUGHING AND
WASHED OUT FRONTAL BOUNDARY NEAR THE AREA. BEST SHOWER CHANCES
WILL AGAIN BE NEAR OR JUST OFFSHORE EARLY MONDAY...THEN SEA BREEZE
CONVERGENCE DURING THE AFTERNOON MAY PROMOTE SCT/ISO THUNDERSTORMS
FOR THE SECOND HALF OF THE DAY INLAND. STILL HOT AND MUGGY WITH
HIGHS IN THE LOW 90S INLAND TO 80S COAST.
TUESDAY THROUGH THURSDAY...WARMING TEMPS AS THICKNESSES AND TEMPS
BUILD WITH HIGHS CLIMBING INTO THE MID 90S (80S COAST). SOME MODEL
DIFFERENCES CONTINUE MID WEEK AS 31/00Z GFS CONTINUES TROUGHING
ALONG THE EAST COAST AND PUSHES A FRONT THROUGH THE AREA LATE
WED/THU WITH A WAVE DEVELOPING ALONG IT... WHILE THE ECMWF HAS
BERMUDA HIGH AS MAIN FEATURE AND THERMAL TROUGHING INLAND. WILL
TREND WITH WPC/ECMWF AND PREVIOUS FORECAST WITH HIGH OFFSHORE AND
PRED S/SW FLOW ACROSS THE AREA. WILL CONTINUE SC POPS...THINKING
PRIMARILY DIURNALLY DRIVEN AT THIS TIME AND MAINLY AWAY FROM THE
COAST.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 12Z SATURDAY/...
AS OF 3 AM FRI...FOG/LOW CLOUD DEVELOPMENT WITH MVFR/IFR
CONDITIONS PSBLE INTO THE EARLY MORN HOURS IN ADVANCE OF THE
FRONT. FRONT WILL HANG UP ALONG THE COAST TODAY WITH SUB VFR
CONDITIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS...MAINLY IN THE
AFTERNOON FOR SOUTHERN AREAS POSSIBLY AFFECTING OAJ AND EWN. WILL
HAVE VCTS FOR THE AFTN AFT 18Z AND VCSH AFT 00Z TNGT FOR THESE TAF
SITES.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...PRED VFR CONDITIONS EXPECTED THROUGH THE
PERIOD. A FRONT WILL STALL NEAR THE COAST OR JUST OFFSHORE THROUGH
THE WEEKEND. ISOLATED TO SCT SHOWERS/TSTMS SAT THROUGH EARLY NEXT
WEEK...WITH BEST CHANCES AT EWN/OAJ. PATCHY FOG/STRATUS POSSIBLE
EACH NIGHT WITH LIGHT WINDS ESP FOR AREAS THAT RECEIVE RAINFALL.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 1240 PM FRIDAY...STILL GENERALLY NORTHERLY WINDS OVER THE
COASTAL WATERS AND SOUNDS...ALTHOUGH SEEING WINDS VEER TO MORE
SOUTHEAST OVER THE FAR SOUTHERN WATERS. SPEEDS REMAIN LESS THAN
15 KNOTS WITH SEAS OF 3 TO 4 FEET. WILL SEE SOUTHWEST WINDS
DEVELOP WITH A FAIRLY PRONOUNCED SEA BREEZE THIS AFTERNOON OVER
SOUTHERN SECTIONS...WITH LIGHT NORTH WINDS CONTINUING NORTH OF
OCRACOKE. WINDS GRADUALLY BECOME SE TO S TONIGHT 10 KT OR LESS.
WINDS BECOME SW THROUGHOUT TOWARD SAT MORN HIGHEST SRN COASTAL
WATERS. SEAS WILL RANGE 2-4 FT TONIGHT.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...THE COLD FRONT WILL WASH OUT BY SAT WITH
SOUTHERLY FLOW ONCE AGAIN DEVELOPING. GRADIENT TIGHTENS THROUGH
THE DAY SAT WITH INCREASING SSW WINDS 10-15KT CONT INTO SUN. A
PERIOD OF MARGINAL SCA CONDITIONS LIKELY TO DEVELOP SUN
NIGHT...MAINLY SOUTH OF OREGON INLET...WITH WINDS INCREASING TO
15-25KT AND SEAS BUILDING TO 4-7FT. GUSTY SW WINDS EXPECTED TO
CONTINUE INTO TUE...WITH LINGERING 6FT SEAS POSSIBLE INTO TUE
NIGHT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JAC
NEAR TERM...CTC
SHORT TERM...JAC
LONG TERM...CQD/TL
AVIATION...CTC/TL
MARINE...CTC/TL
AREA FORECAST DISCUSSION
NWS NORMAN OK
1220 PM CDT FRI JUL 31 2015
.UPDATE...
UPDATE TO PRECIP/WX...
&&
.DISCUSSION...
SCATTERED SHOWERS AND ISOLATED THUNDER ACROSS CENTRAL OK CONTINUES
TO WEAKEN... BUT REMAIN PERSISTENT. MUCH... IF NOT ALL OF THIS
ACTIVITY IS LIKELY TIED TO MODEST LOW LEVEL ASCENT ASSOCIATED WITH
A WEAK 850MB TROUGH AND VARIOUS WEAKENING OUTFLOW BOUNDARIES
ASSOCIATED WITH EARLIER CONVECTION. FOR THIS AFTN... PRIMARY FOCUS
IS ON CONTINUOUS ACTIVITY ACROSS THE TX PH... AS NEW UPDRAFTS HAVE
STARTED TO DEVELOP ON OR JUST WEST OF THE OK/TXPH BORDER.
DIFFICULT TO PINPOINT EXACT FORCING FOR ASCENT... BUT IT APPEARS
TIED TO SFC/LL CONVERGENCE. LATEST HRRR RUN HAS MOST OF THIS
ACTIVITY DISSIPATING THROUGH EARLY/MID AFTN AS UPPER LVL SUPPORT
FROM THE WEAK H500 SHORT WAVE EMBEDDED IN THE LARGER RIDGE EXITS
TO THE EAST. INITIAL STORMS IN WRN OK WILL RESIDE IN A REGION OF
MODEST INSTABILITY... SUPPORTIVE OF GUSTY WINDS AND LOCALLY HEAVY
RAINFALL. NOT EXPECTING ANY ORGANIZED SEVERE STORMS THROUGH THIS
AFTN.
JTK
&&
.PREV DISCUSSION... /ISSUED 614 AM CDT FRI JUL 31 2015/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED.
SOME MVFR...PERHAPS IFR...CONDITIONS MAY AFFECT KWWR AND KGAG
THROUGH 16Z.
ISO-SCT SHRA/TSRA WILL BE OVER THE AREA FOR THE NEXT 24 HOURS.
ONLY INCLUDED VCTS AND VCSH NEAR KOKC AND KOUN THROUGH 16-17Z
WHERE CONFIDENCE OF OCCURRENCE IS HIGHER. PINPOINTING WHERE AND
WHEN SHRA/TSRA OCCUR REMAINS VERY TRICKY AND CHALLENGING...SO DID
NOT MENTION IN MANY TAFS AS COVERAGE SHOULD BE LOW. BRIEF MVFR OR
LOWER CONDITIONS AND VARIABLE GUSTY WINDS ARE POSSIBLE WITH
SHRA/TSRA.
MBS
PREV DISCUSSION... /ISSUED 309 AM CDT FRI JUL 31 2015/
DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 71 91 71 91 / 10 10 20 10
HOBART OK 71 89 70 93 / 30 30 20 10
WICHITA FALLS TX 74 96 73 95 / 20 20 20 10
GAGE OK 68 86 67 92 / 20 20 30 10
PONCA CITY OK 71 91 72 92 / 10 10 20 10
DURANT OK 73 97 73 95 / 10 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS NORMAN OK
1213 PM CDT FRI JUL 31 2015
.AVIATION...
ISOLATED TO SCATTERED SHOWERS AND STORMS WILL CONTINUE THROUGH
THE AFTERNOON AND OVERNIGHT...BUT DID NOT MENTION IN TAFS BECAUSE
CONFIDENCE IN STORMS IMPACTING ANY PARTICULAR LOCATION IS LOW.
EXPECT MID CLOUDINESS TO PERSIST...THOUGH CONDITIONS SHOULD
REMAIN GENERALLY VFR. LIGHT EAST WINDS WILL GRADUALLY SHIFT TO
THE SOUTH OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 614 AM CDT FRI JUL 31 2015/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED.
SOME MVFR...PERHAPS IFR...CONDITIONS MAY AFFECT KWWR AND KGAG
THROUGH 16Z.
ISO-SCT SHRA/TSRA WILL BE OVER THE AREA FOR THE NEXT 24 HOURS.
ONLY INCLUDED VCTS AND VCSH NEAR KOKC AND KOUN THROUGH 16-17Z
WHERE CONFIDENCE OF OCCURRENCE IS HIGHER. PINPOINTING WHERE AND
WHEN SHRA/TSRA OCCUR REMAINS VERY TRICKY AND CHALLENGING...SO DID
NOT MENTION IN MANY TAFS AS COVERAGE SHOULD BE LOW. BRIEF MVFR OR
LOWER CONDITIONS AND VARIABLE GUSTY WINDS ARE POSSIBLE WITH
SHRA/TSRA.
MBS
PREV DISCUSSION... /ISSUED 309 AM CDT FRI JUL 31 2015/
DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 71 91 71 / 30 10 10 20
HOBART OK 94 71 89 70 / 20 30 30 20
WICHITA FALLS TX 96 74 96 73 / 20 20 20 20
GAGE OK 88 68 86 67 / 30 20 20 30
PONCA CITY OK 91 71 91 72 / 20 10 10 20
DURANT OK 96 73 97 73 / 20 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/14/14
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
143 PM EDT FRI JUL 31 2015
.SYNOPSIS...
DRY HIGH PRESSURE WILL BUILD IN BEHIND A DEPARTING COLD FRONT TODAY
AND REMAIN IN PLACE THROUGH THE WEEKEND. LOW LEVEL MOISTURE WILL
GRADUALLY RETURN THROUGH NEXT WEEK AS ANOTHER COLD FRONT APPROACHES
FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM EDT FRIDAY...FORECAST RUNNING PRETTY MUCH ON TRACK
WITH NOT MUCH IN THE WAY OF SENSIBLE WEATHER TO WRITE HOME ABOUT.
DESPITE THE HEAT...A FAIRLY NICE DAY WITH DEWPOINTS LOWER IN THE
WAKE OF THE WEAK FRONTAL PASSAGE. VERY LITTLE CHANGES MADE TO THE
GRIDS THIS MORNING...HAVE UPDATED TEMPS AND DEWPOINTS BASED ON
TRENDS AND IT IS POSSIBLE THAT HIGHS MIGHT BE JUST A TOUCH LOWER
THAN FORECAST BUT WILL CONTINUE TO MONITOR. POPS LOOK GOOD FOR
NOW...SPC DAY1 OUTLOOK DOES INCLUDE EXTREME SOUTHEAST PORTIONS OF
THE CWA IN GENERAL THUNDER BUT LOOKING AT THE HRRR AND OTHER CAMS
SEEMS WE WILL BE PRETTY HARD-PRESSED TO SEE CONVECTION TODAY. CLOUDS
WILL CONTINUE TO SCATTER OUT OVER THE NEXT COUPLE OF HOURS.
1045 UTC UPDATE...SKY COVER WAS UPDATED FORM INFRARED SATELLITE
IMAGERY...RESULTING IN A DECREASE. POPS WERE ADJUSTED DOWN PER
TRENDS.
AT 300 AM EDT FRIDAY...AN UPPER RIDGE WILL SLOWLY RETROGRESS TODAY AND
TONIGHT FROM THE SOUTHERN PLAINS TO THE SOUTHERN ROCKIES...WHILE AN
UPPER TROUGH AMPLIFIES OVER THE EASTERN USA. A COLD FRONT WILL MOVE
SLOWLY SOUTH AND OUT OF OUR AREA...STALLING NEAR THE COAST OF THE
CAROLINAS AND GA. MOISTURE ASSOCIATED WITH THIS BOUNDARY APPEARS TO
GENERALLY REMAIN JUST SE OF OUR AREA...OFFERING LITTLE SUPPORT FOR
CONVECTION. TEMPERATURES WILL RUN NEAR NORMAL TODAY AND TONIGHT AS
WEAK COOL ADVECTION IS OFFSET BY LIMITED DOWNSLOPE WARMING FLOW IN
LIGHT NORTHERLY WINDS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 150 AM FRIDAY...QUIET WEATHER EXPECTED THRU THE SHORT RANGE.
AN UPPER TROF REMAINS ACROSS MUCH OF THE ERN CONUS WITH NO
SIGNIFICANT SHORT WAVE ENERGY MOVING THRU THE TROF. AT THE SFC...
DRY HIGH PRESSURE BUILDS IN ACROSS THE AREA SAT AND SUN. GUIDANCE
BLEND SHOWS DEW POINTS MIXING OUT INTO THE 50S ACROSS THE AREA BOTH
DAYS. THIS COMBINED WITH RELATIVELY WARM MID LEVEL AIR WILL LEAD TO
LITTLE TO NO CAPE EACH AFTERNOON...RESULTING IN VERY LOW POTENTIAL
FOR DEEP MOIST CONVECTION. A REMNANT COLD FRONT BOUNDARY WILL BE
CLOSE BUT SOUTH OF THE AREA PROVIDING LITTLE TO NO LOW LEVEL
CONVERGENCE FOR THE AREA. THEREFORE...HAVE GONE WITH A DRY FCST.
EXPECT TEMPS TO BE NEAR TO A LITTLE ABOVE NORMAL THRU THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 255 AM FRIDAY...GUIDANCE IS IN DECENT AGREEMENT THRU THE
PERIOD. EAST COAST TROF FLATTENS THRU THE PERIOD WITH WLY FLOW
DEVELOPING ACROSS THE AREA AS HEIGHTS RISE. THIS ALLOWS A SERIES OF
SHORT WAVES TO MOVE ACROSS OR NEAR THE AREA. THE DRY HIGH PRESSURE
OVER THE AREA SLOWLY MODERATES THEN DISSIPATES AS A COLD FRONT DROPS
SOUTH TOWARD THE AREA. THE COLD FRONT INITIALLY STALLS...THEN MOVES
INTO THE AREA THU AS A LOW PRESSURE AREA TRACKS FROM THE OH VALLEY
OFF THE MID ATLANTIC COAST. THE RESULT IS AN INCREASE IN LOW LEVEL
MOISTURE AND INSTABILITY THRU THE PERIOD. THE BEST FORCING...AND
RESULTANT CONVECTION...WILL BE WED AND THU...WITH A DRY FCST MON AND
ONLY ISOLATED CONVECTION TUE ACROSS THE MTNS. WITH THE RISING
HEIGHTS AND LINGERING HIGH PRESSURE MON AND TUE...TEMPS WILL BE
ABOVE NORMAL. TEMPS SLOWLY FALL WED AND THU...BUT REMAIN ABOVE
NORMAL.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...VFR...WITH THE POSSIBLE EXCEPTION OF BRIEF
MVFR FOG AT KHKY BETWEEN 06-12Z SATURDAY BUT CHANCE NOT HIGH ENOUGH
TO INCLUDE IN TAF AT THIS TIME. VERY LITTLE MOISTURE TO WORK WITH IN
THE WAKE OF THE FRONT THIS MORNING SO EXPECT AT BEST FEW TO SCT
CLOUDS AROUND 5-6KFT FOR THIS AFTERNOON...WITH POSSIBLY ANOTHER
ROUND SATURDAY AFTERNOON...BUT MOISTURE IS EVEN MORE LIMITED BY THAT
POINT. COULD SEE PASSING CIRRUS OFF AND ON AS WELL. DO NOT EXPECT
ANY CONVECTION THROUGH THE PERIOD AT THE TAF SITES. WINDS SHOULD
REMAIN GENERALLY N TO NE WITH ONLY BRIEF SWINGS TOWARD E...BUT
REMAINING ON THE N SIDE. COULD SEE SOME OFF-AND-ON LOW-END GUSTS
THROUGH THIS AFTERNOON BUT WINDS SHOULD DIE OFF LATER THIS EVENING
AND OVERNIGHT TO GENERALLY 5KT OR BELOW EVERYWHERE.
OUTLOOK...EXPECTING GENERALLY DRY AND QUIET WEATHER THROUGH THE
WEEKEND WITH A GRADUAL INCREASE IN CHANCES FOR SHOWERS/THUNDERSTORMS
AND RESTRICTIONS 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% HIGH 100% 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...RWH
NEAR TERM...TDP
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
309 PM CDT FRI JUL 31 2015
.SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)...HAVE FINALLY
DEVELOPED SOME ISOLATED TO SCATTERED SHOWERS AND A FEW
THUNDERSTORMS ACROSS THE AREA THIS AFTERNOON. HRRR MODEL HANDLING
THIS REASONABLY WELL...ENDS MOST OF THE ACTIVITY BY ABOUT 02Z. HAVE
20 POPS AREA WIDE FOR THE EVENING...WITH 10S AND 20S AFTER
MIDNIGHT. GLOBAL MODELS CONTINUE TO STRUGGLE WITH QPF...GFS
DEFINITELY STILL TOO AGGRESSIVE. SOMETHING OF A MIX BETWEEN NAM
AND ECMWF APPEARS THE BEST. THAT SAID...BOTH OF THOSE MODELS ARE
QUIET ON SATURDAY...EXCEPT IN MARINE AREA. HAVE CUT POPS FOR
INLAND AREAS IN THE MORNING...BUT WILL LEAVE A 20 POP AREA WIDE
FOR THE AFTERNOON AS HIGH MOISTURE AIR WILL STILL BE IN PLACE AND
COULD GET SOME SHOWERS TO POP UP ONCE AGAIN.
WITH NO MAJOR PATTERN CHANCE...EXPECT TEMPERATURES TOMORROW TO
APPROACH THE SAME VALUES WE/RE SEEING TODAY AS WE SHOULD KEEP A
LIGHT AND VARIABLE WIND...NOT THE ONSHORE FLOW WE ARE USED TO THIS
TIME OF YEAR. HAVE HIGHS MAINLY IN THE UPPER 90S TO AROUND 100
ACROSS THE AREA. HEAT INDEX VALUES WILL BE AT LEAST BETWEEN 100
AND 105...BUT COULD BE 105 TO 109 IF WE DON`T MIX OUT THE NEAR
SURFACE MOISTURE.
&&
.LONG TERM (SUNDAY THROUGH FRIDAY)...EXTENDED FORECAST LOOKS
RELATIVELY STRAIGHTFORWARD WITH UPPER RIDGE AXIS REPOSITIONING
ITSELF OVER THE SOUTHERN PLAINS AND SURFACE LEE DEVELOPMENT
GENERATING TYPICAL ONSHORE FLOW REGIME ACROSS THE COASTAL BEND. ANY
LINGERING PRECIPITATION CHANCES WITH A DECAYING BOUNDARY ON SUNDAY
SHOULD BE CONFINED TO OFFSHORE ZONES...THEN A DRY FORECAST THROUGH
THE WEEK.
TEMPERATURES WILL REMAIN A CATEGORY OR SO ABOVE NORMAL THROUGH THE
PERIOD. HEAT INDEX LEVELS WILL FLIRT WITH SPS CRITERIA ON A DAILY
BASIS...THOUGH ACTUAL ADVISORY CRITERIA HEAT APPEARS UNLIKELY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 76 98 76 96 77 / 20 20 10 10 10
VICTORIA 74 100 74 98 75 / 20 20 10 10 10
LAREDO 78 103 78 103 78 / 20 20 10 10 0
ALICE 75 100 75 98 75 / 20 20 10 10 10
ROCKPORT 76 95 79 91 80 / 20 20 10 10 10
COTULLA 77 102 75 103 76 / 20 20 10 0 0
KINGSVILLE 75 99 76 98 76 / 20 20 10 10 10
NAVY CORPUS 78 92 79 90 80 / 20 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
PZ/83...SHORT TERM
JV/71...LONG TERM
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
343 PM CDT FRI JUL 31 2015
.SHORT TERM...TONIGHT THROUGH MONDAY.
TONIGHT AND SATURDAY - CONFIDENCE...MEDIUM
STRONG NW MID LEVEL FLOW PERSISTS WITH PRIMARY SHORTWAVE OF NOTE
TRAVERSING THROUGH LAKE SUPERIOR INTO LWR MI REGION TONIGHT.
NAM/ARW/NMM/HRRR ALL SHOWING SOME LIGHT PRECIP DEVELOPING LATER IN
THE NIGHT DUE TO LOW LEVEL CONVERGENCE ASSOCIATED WITH SURFACE/850
TROUGH. NOT MUCH SHOWING ON THIS UPSTREAM AND WITH OVERALL DRY AIRMASS
AND POOR TIMING THERMODYNAMICALLY CONFIDENCE NOT GREAT IN MUCH IF
ANYTHING EVOLVING. RAP SOUNDINGS ARE ALL VERY DRY WITH LITTLE IN THE
WAY OF ELEVATED CAPE. HOWEVER NAM/GFS AND HRRR SOUNDINGS SHOW A LITTLE
BETTER MID LEVEL MOISTENING WITH SOME ELEVATED CAPE. CONSENSUS OF MOS
POPS ARE IN THE SINGLE DIGITS. WILL CARRY A A SMALL AREA OF SLGT POPS
FROM LATE TONIGHT INTO EARLY SATURDAY ACROSS PORTIONS OF WRN AND SRN
CWA. FROM LATER IN THE MORNING INTO THE AFTERNOON SURFACE/850 RIDGING
WILL TAKE HOLD WITH A MORE RELAXED PRESSURE GRADIENT IN PLACE TO
SUPPORT A LIGHTER WIND REGIME. 925 TEMPS AVERAGE 22-23C SO EXPECTING
HIGHS BACK INTO THE 80S.
SATURDAY NIGHT...FORECAST CONFIDENCE MEDIUM
WEAK SHORT WAVE APPROACHES SATURDAY NIGHT...CENTERED OVER CWA AT 12Z
SUNDAY...MOVING EAST OF AREA BY 18Z....WITH STRONGER SHORT WAVE
TROUGH MOVING INTO NORTH DAKOTA BY 12Z SUNDAY. LOW-LEVEL THETA-E
ADVECTION MAX CROSSES CWA BETWEEN 03Z AND 06Z SUNDAY...HOWEVER
STRONGER OMEGA TIED WITH STRONGEST FRONTOGENETIC RESPONSE OVER NE WI
TO FOCUSED WARM AIR ADVECTION WITH THE 35-40 KT LOW-LEVEL JET MAX
AHEAD OF STRONG WAVE TO THE NORTHWEST. THIS BETTER FORCING ON THE
NOSE OF THE LLJ SHIFTS EAST AS THE AXIS OF THE LLJ DROPS SOUTH
THROUGH THE STATE OVERNIGHT...BRUSHING THE EASTERN CWA. WILL KEEP
HIGH CHANCE POPS GOING FOR AFTER MIDNIGHT...WITH LATER SHIFTS
POSSIBLY ABLE TO RAISE WITH BETTER CLARITY FROM LATER MODEL RUNS.
SUNDAY...FORECAST CONFIDENCE MEDIUM
PERSISTENT LOW-LEVEL FLOW CONTINUES OVER AREA AHEAD OF SECOND...
STRONGER SHORT WAVE AND ASSOCIATED SURFACE LOW AND COLD FRONT
DIPPING INTO NRN WI BY 00Z MONDAY. PLENTY OF FORCING ALONG/AHEAD OF
850 MB TROUGH AXIS AND SURFACE FRONT BUT STRONG AND DEEP CAPPING
NOTED ON FORECAST SOUNDINGS ESPECIALLY OVER THE WESTERN CWA WITH
PERSISTENT WARM AIR ADVECTION. LESS OF A CAP OVER EASTERN AREAS WITH
HIGHER PW/S. WILL HAVE LOWER CHANCE POPS IN THE MORNING FOR
DEPARTING WARM-AIR ADVECTION FORCING...AND KEEP THEM IN THE
AFTERNOON FOR INSTABILITY AND APPROACHING LOW-LEVEL FORCING WITH THE
LOW.
SUNDAY NIGHT...FORECAST CONFIDENCE MEDIUM
SECOND STRONGER SHORT WAVE DROPS IN SUNDAY NIGHT PUSHING LOW AND
COLD FRONT THROUGH THE SOUTHERN HALF OF THE STATE. BETTER CHANCES
FOR SHOWERS AND STORMS IN THE EVENING BEFORE FRONT DROPS SOUTH IN BY
06Z...WITH CAP ERODING AS MID-LEVELS COOL. KEPT A COLLABORATIVE
SLIGHT CHANCE AFTER 06Z...BUT LOOKS AS IF PCPN WILL BE SOUTH OF AREA
BY 06Z.
MONDAY...FORECAST CONFIDENCE HIGH
DRY WEATHER WITH HIGH PRESSURE BUILDING IN WITH SLIGHTLY COOLER
TEMPERATURES...BUT WITH DEW POINTS FALLING INTO THE 50S WITH DEEP
MIXING.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE LOW
MODELS DIFFER WITH LOCATION OF STATIONARY FRONT TO THE SOUTH AND HOW
FAR NORTH PRECIPITATION SHIELD WILL REACH AS WAVE MOVES ALONG
STALLED BOUNDARY TUESDAY AND WEDNESDAY. MOST MODELS KEEP PCPN SOUTH
OF STATE TUESDAY AND SPLIT ON HOW FAR NORTH TO BRING COVERAGE
WEDNESDAY. WITH DRY BROAD HIGH IN PLACE OVER WESTERN GREAT LAKES
WILL GO WITH CONSERVATIVE CONSENSUS SLIGHT CHANCE POPS FOR
WEDNESDAY...WITH CHANCE POPS LIMITED TO THE IL BORDER. MORE
PROGRESSIVE GFS BRINGS A STRONGER LOW ACROSS OR THURSDAY
AFTERNOON/NIGHT WITH ECMWF KEEPING AREA DRY INTO FRIDAY NIGHT.
RESULTING BLEND BRINGS SLIGHT/LOW CHANCES FOR SHOWERS/STORMS FOR THE
END OF THE EXTENDED...THOUGH NOT EVERY PERIOD WILL EVENTUALLY HAVE
PRECIPITATION. AFTER HIGHS IN THE LOW 80S TUESDAY...TEMPERATURES
WILL COOL INTO THE 70S FOR THE REST OF THE EXTENDED...WITH LOWS
MAINLY IN THE 50S.
&&
.AVIATION/00Z TAFS/...WNW WINDS EXPECTED TO EASE A BIT THIS EVENING
WITH LOSS OF HEATING. NAM/LATEST HRRR/ARW/NMM WANT TO GENERATE SOME
LIGHT PRECIP INTO SC WI LATE TNGT/ERLY SAT BUT WILL LEAVE MENTION
OUT OF TAF AT THIS TIME. WITH SURFACE/850 RIDGE DRAWING CLOSER ON
SATURDAY EXPECT AN OVERALL LIGHTER WIND REGIME.
&&
.MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH THE AFTERNOON
DUE TO GUSTY WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS. A FEW GUSTS
MAY REACH 30 KNOTS AT TIMES. WINDS WILL DIMINISH EARLY THIS
EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
TONIGHT/SATURDAY AND AVIATION/MARINE...COLLAR
SATURDAY NIGHT THROUGH FRIDAY...REM