Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/25/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1257 PM MST THU JUL 23 2015
.SYNOPSIS...
ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN
ARIZONA TODAY AND TOMORROW...WHILE THE REST OF THE REGION SHOULD
REMAIN DRY. SHOWERS SHOULD REMAIN CONFINED TO THE MOUNTAINS EAST OF
PHOENIX THIS WEEKEND ALTHOUGH STORM CHANCES SHOULD INCREASE AREA-WIDE
NEXT WEEK. AS FOR TEMPERATURES...EXPECT A GRADUAL RISE THROUGH THE
WEEKEND WITH DESERT HIGHS APPROACHING THE 110 DEGREE MARK IN SPOTS.
&&
.DISCUSSION...
EARLY AFTERNOON SATELLITE AND RADAR IMAGERY REVEALS A PERSISTENT AREA
OF SHOWERS ACROSS EASTERN ARIZONA. WHILE THE SMALL COMPLEX THAT WAS
ONGOING EARLIER THIS MORNING HAS SINCE DISSIPATED...NEW CONVECTION
HAS STARTED TO FORM ACROSS SOUTHEAST ARIZONA. THIS IS WITHIN AN AREA
OF 1.7-1.8 INCH PWATS THAT CREPT NORTHWARD OVERNIGHT COURTESY OF A
DECAYING SONORAN MCS. SOME MOISTURE ALSO MANAGED TO CREEP UP THE
GULF OF CALIFORNIA ALTHOUGH SOUNDINGS OUT OF YUMA INDICATE THE LAYER
WAS QUITE SHALLOW AND PWATS ARE ONLY AROUND 0.9 INCHES /NOT
SURPRISING GIVEN A QUICK GLANCE AT WV IMAGERY/. ACROSS THE CENTRAL AZ
DESERTS...SKIES REMAINED PARTLY TO MOSTLY SUNNY WITH TEMPS RIGHT
AROUND 100 DEGREES AS OF 19Z.
MODELS HAVE BEEN STRUGGLING A BIT TODAY AND DID NOT INITIALIZE THIS
MORNING`S CONVECTION WELL. THUS QUITE A FEW HI-RES MODELS INDICATE A
VERY ACTIVE DAY ACROSS PARTS OF THE AREA WHEREAS IN
REALITY...EXTENSIVE CLOUD COVER WILL LIKELY KEEP STORMS IN CHECK AND
LIMIT DAYTIME HEATING. THE PAST FEW RUNS OF THE HRRR SEEM TO HAVE
CAUGHT ONTO REALITY AND INDICATE A FEW SHOWERS TRYING TO MAKE THEIR
WAY INTO FAR SW MARICOPA...PARTS OF PINAL...AND SOUTHERN GILA
COUNTIES BEFORE FALLING APART. THE ATMOSPHERE WEST OF TUCSON APPEARS
TO BE FAVORABLE FOR STORM DEVELOPMENT /AT LEAST ACCORDING TO THE
HRRR/ AND AS THOSE CONDITIONS WILL BE ADVECTED NORTHWARD THIS
AFTERNOON...I WANT TO MAKE AT LEAST A SLIGHT MENTION /10 PERCENT/ OF
SHOWERS AND STORMS IN THE PHOENIX AREA THIS AFTERNOON. HRRR WOULD
LEAD ONE TO BELIEVE NOTHING WILL SURVIVE INTO THE LOWER DESERTS BUT
WITH A WEAK REMNANT CIRCULATION ROTATING THROUGH EASTERN
ARIZONA...DON`T WANT TO DISCOUNT STORM CHANCES ENTIRELY. AS FOR
BLOWING DUST AS A THREAT THIS AFTERNOON...STILL A POSSIBILITY SOUTH
AND EAST OF PHOENIX BUT EVEN THE HRRR ISN`T TOO ENTHUSED WITH THE
IDEA OF GUSTY OUTFLOW WINDS /LIKELY DUE TO INCREASE BL MOISTURE VS.
AN INVERTED-V PROFILE/.
LOOKING AHEAD TO FRIDAY...SIMILAR CONDITIONS WILL RESIDE ACROSS THE
AREA AND ONCE AGAIN IT MAY DEPEND ON THE PRESENCE OF ANY UPSTREAM
MCVS TO KICK ANYTHING OFF ACROSS THE AREA. INHERITED POPS INDICATED
10-20 PERCENT CHANCES FROM PHOENIX EASTWARD AND THIS STILL SEEMS
REASONABLE. NEARLY ALL HI-RES ENSEMBLES INDICATE TOMORROW WILL BE A
DOWN DAY...BUT GLOBAL GUIDANCE STILL SUGGESTS THE POSSIBILITY OF A
WEAK INVERTED TROUGH MOVING THROUGH EASTERN ARIZONA FRIDAY AFTERNOON.
WOULD PREFER TO MAINTAIN SOMETHING ALONG THE LINES OF CLIMO IN PLACE
VS. DROPPING BACK INHERITED VALUES.
GFS/NAM/EC AND ASSOCIATED ENSEMBLES INDICATE A SUBTLE DRYING TREND
THIS WEEKEND...CONSEQUENTLY TEMPERATURES WILL CLIMB SLIGHTLY AND
APPROACH THE 110 DEGREE MARK IN THE NORMALLY WARMER LOCATIONS. POPS
WERE ALREADY ORIENTED WELL NORTH/EAST OF PHOENIX THIS WEEKEND AND
THIS STILL SEEMS MORE THAN REASONABLE WITH SSW FLOW ALOFT. ONLY MINOR
CHANGES MADE TO THE FORECAST FOR THIS WEEKEND.
MONDAY THROUGH WEDNESDAY...
MODELS ARE ALSO SHOWING A PROGRESSIVE EASTERLY FLOW ACROSS MEXICO
WITH SOME EMBEDDED WAVES THAT SPILL INTO THE PACIFIC. THIS ACTIVITY
MIGHT BRING A MORE PROMISING INCREASE OF LOW LEVEL MOISTURE INTO THE
DESERT SOUTHWEST...BUT IT WILL BE DEPENDENT ON THE HOW FAR WEST THE
RIDGE OF HIGH PRESSURE EXPANDS. RIGHT NOW...MODELS SHOW THE BEST LOW
LEVEL MOISTURE ARRIVING LATE SUNDAY/MONDAY.
OVERALL...A GRADUAL UPTICK IS EXPECTED IN SHOWER AND THUNDERSTORM
ACTIVITY AS WE GO INTO EARLY NEXT WEEK... ESPECIALLY OVER EASTERN
ARIZONA AND THE RIM COUNTY. STILL...LOW GRADE MONSOON CONDITIONS ARE
EXPECTED INTO EARLY NEXT WEEK WITH MOST OF THE THUNDERSTORMS LIKELY
TO BE CONFINED TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF CENTRAL
PHOENIX.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SOLID SCT-BKN CIG SHIELD WILL REMAIN ACROSS THE FAR EASTERN PHX
METRO AND EASTERN AZ HIGHER TERRAIN THROUGH THE AFTERNOON. IT WILL
ALSO BECOME REINFORCED BY ADDITIONAL THUNDERSTORM BLOW OFF FROM
SOUTHEAST AZ. MAINLY CLEAR SKIES TO REMAIN ACROSS MUCH OF THE PHX
METRO AND WESTERN DESERTS THROUGH THE AFTN TRAFFIC PUSH. VARIABLE
SURFACE WINDS WILL EVENTUALLY TAKE UP WESTERLY HEADINGS WITH
ISOLATED GUSTINESS NEAR 20KTS. HI-RES MODELS INDICATE POTENTIAL FOR
STORM POP-UPS NEAR THE PINAL-MARICOPA-PIMA COUNTY BORDER ALONG I-8
WHICH MAY SEND S-SW OUTFLOW AND GUSTS IN FOR KPHX AND PSBLY KIWA BY
THE EARLY EVENING. WILL HOLD OFF FROM PLACING THOSE CHANGE GROUPS IN
THE TAFS UNTIL PSBL STORMS BECOME ESTABLISHED IN THAT AREA ON THE
RADAR.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
MOSTLY CLEAR SKIES AND PERSIST SE-S WINDS TO HOLD THROUGH THE AFTN
FOR THE TERMINALS. WEST SUNDOWNER WINDS TO DEVELOP INTO KIPL UP TO
12KTS OVERNIGHT BEFORE BECOMING SOUTHEASTERLY AGAIN TOWARDS FRIDAY
AM.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH THURSDAY...
LOW-GRADE MONSOON PATTERN EXPECTED INTO THE WEEKEND THROUGH NEXT WEEK
AS STORM CHANCES APPEAR TO BE FOCUSED IN THE MOUNTAINS NORTH/EAST OF
PHOENIX. THERE MAY BE AN INTRUSION OF DEEPER MOISTURE BY THE MIDDLE
OF THE WEEK WHICH WOULD RESULT IN SUBSTANTIALLY HIGHER HUMIDITIES AND
ELEVATED RAINFALL CHANCES ACROSS THE ENTIRE AREA...BUT THIS IS STILL
UP FOR DEBATE IN THE ENSEMBLES. FOR NOW I MAINTAINED CLIMO-LIKE POPS
NEXT WEEK. AS FOR HUMIDITIES...EXPECT SINGLE DIGIT AFTERNOON READINGS
ACROSS THE REGION WITH GOOD OVERNIGHT RECOVERIES. HUMIDITIES WILL
GRADUALLY CREEP UPWARD THROUGH THE WEEK. WINDS SHOULD BE LIGHT AND
MAINTAIN TYPICAL DIURNAL UPSLOPE/DOWNVALLEY PATTERNS.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION NOT EXPECTED THURSDAY BUT MAY BE POSSIBLE ON FRIDAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...LEINS
AVIATION...NOLTE
FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
933 AM MDT THU JUL 23 2015
.UPDATE...
ISSUED AT 927 AM MDT THU JUL 23 2015
SATELLITE IMAGERY CONTINUES TO SHOW CLEARING OVER LINCOLN COUNTY
AS THE REGION IS UNDER A DRIER WEATHER PATTERN. WITH DECREASED
MOISTURE AND CLEARING SKIES HAVE INCREASED TEMPERATURES OVER THE
FRONT RANGE A FEW DEGREES BUT OVERALL ON TRACK TO REACH THE MID
90S TODAY. LATEST HRRR GUIDANCE SHOWING SOME DEVELOPMENT OVER THE
SOUTHERN MOST PORTIONS OF THE REGION SOUTH OF I-70 ALONG THE
FOOTHILLS AS WELL AS DOUGLAS AND LINCOLN COUNTIES LATER THIS
AFTERNOON. THIS COINCIDES WITH SOME MOISTURE THAT WILL MAKE ITS
WAY INTO THE AREA LATER THIS AFTERNOON BUT NOT VENTURE ANY
FURTHER NORTH THAN I-70. DO NOT EXPECT MUCH OUT OF THESE STORMS
BUT SOME LIGHT TO MODERATE RAIN.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 419 AM MDT THU JUL 23 2015
A LITTLE BIT OF WARMING ALOFT SHOULD LIMIT CONVECTION
TODAY...THOUGH THERE IS STILL ENOUGH MOISTURE AROUND FOR SOME
CLOUD DEVELOPMENT AND ISOLATED STORMS. MOISTURE WILL BE BETTER IN
THE SOUTHERN PART OF THE AREA. PREVIOUS FORECAST LIMITED THE
MENTION OF POPS TO THE MOUNTAINS SOUTH OF INTERSTATE 70...AND THEN
AREAS NEAR THE FOOTHILLS FROM DENVER SOUTHWARD DURING THE EVENING.
WILL STICK WITH THIS IDEA...JUST ENDING THE THREAT BY MID EVENING.
TEMPERATURES SHOULD BE A FEW DEGREES WARMER...WHICH MEANS MOSTLY
MID 90S ON THE PLAINS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 419 AM MDT THU JUL 23 2015
AMPLIFIED WAVE PATTERN OVER THE WESTERN CONUS FIRST HALF OF THE
PERIOD WITH UPPER RIDGE OVER THE LOWER GREAT PLAINS AND TROUGH
OVER THE PACIFIC NORTHWEST FLATTENS OUT WITH FLOW ALOFT BECOME
NEARLY ZONAL LATE IN THE PERIOD. MODELS IN REASONABLY GOOD
AGREEMENT THOUGH THE GFS CONTINUES TO BE THE WETTER OF THE MEDIUM
RANGE MODELS AS IT IS RELUCTANT TO SEVER THE TIE TO THE SOUTHWEST
MONSOON. ON FRIDAY...COLORADO REMAINS SANDWICHED BETWEEN A STRONG
UPPER RIDGE AND BERMUDA SFC HIGH OVER THE SOUTHERN GREAT PLAINS
AND AN UPPER TROUGH WHICH MODELS SHOW SLIPPING SOUTH DOWN THE
PACIFIC NORTHWEST COAST. THE TWO SYSTEMS KEEP THE FORECAST AREA
UNDER SWLY FLOW ALOFT. AGAIN GFS APPEARS WETTER AS IT SHOWS A
COLUMN OF MID/HIGH LEVEL MOISTURE SPREADING OVER THE STATE DURING
THE DAY. WHEREAS THE EUROPEAN AND CANADIAN MODELS SHOW A DRIER AND
SLIGHTLY MORE WESTERLY FLOW ALOFT. AT ANY RATE...INTEGRATED
PRECIPITABLE WATER VALUES START THE DAY ON THE LOW SIDE...E.G.
AROUND A HALF INCH ALONG THE FRONT RANGE...AND THEN STEADILY RISE
THROUGH THE DAY TO AROUND AN INCH WITH THE BNDRY LAYER FLOW
TURNING E-NELY. AND YET..THE PLAINS AIRMASS APPEARS TO REMAIN
STRONGLY CAPPED WITH WARMING ALOFT. CAPE AND STEEP LAPSE RATES
REMAIN LARGELY CONFINED TO HIGHER DEWPOINT AIR ALONG THE EASTERN-
SOUTHEASTERN FRINGE OF THE FCST AREA. FOR THAT REASON WILL ASSIGN
LOW POPS IN THIS AREA...AND INCLUDE LOW POPS IN THE FOOTHILLS AND
SOUTH PARK AREAS. TEMPS ON FRIDAY REMAIN ABOVE AVERAGE WITH
LOW/MID 90S AT LOWER ELEVATIONS AND MOSTLY 70S IN THE HIGH
COUNTRY.
OVER THE WEEKEND...THE SRN PLAINS RIDGE APPEARS TO WEAKEN SLIGHTLY
AND SLIP A BIT FARTHER SOUTHEAST. THIS ALLOWS FOR MORE MONSOONAL
MOISTURE TO MAKES IT WAY UP INTO COLORADO ON SWLY FLOW. GFS
CONTINUES TO RUN WETTER THAN THE OTHER MODELS ALTHOUGH THE EUROPEAN
AND CANADIAN ALSO LOOK WETTER AT LEAST AT MID-LEVELS. PW VALUES ON
THE PLAINS START THE DAY ON A HIGH NOTE AROUND AN INCH...BUT THEN
DROP OFF DURING THE DAY WITH THE SFC-700MB FLOW BNDRY BECOMING W-
SWLY/DOWNSLOPE. HOWEVER SELY BNDRY LAYER FARTHER OUT ON THE PLAINS
KEEPS PW VALUES UP AROUND AND INCH PRODUCING 0-3KM CAPES IN THE 500-
1000 J/KG SUFFICIENT TO KEEP A LOW CHANCE OF AFTERNOON/EVENING T-
STORMS OUT THERE AS WELL AS OVER THE SRN FOOTHILLS AND SOUTH PARK.
ELSEWHERE SHOULD REMAIN STORM FREE. TEMPS ON SATURDAY 1-3DEG F COOLER
THAN FRIDAY DUE IN PART TO GREATER CLOUD COVER. ON SUNDAY...FLOW
ALOFT TURNS MORE WESTERLY LEADING TO LOWER HUMIDITY...LESS CLOUD
COVER AND SLIGHTLY HIGHER TEMPS.
MONDAY-WEDNESDAY...THE PACIFIC NORTHWEST TROUGH IS PROGGED TO
MIGRATE EASTWARD ALONG THE U.S/CANADIAN BORDER FLATTENING OUT THE
FLOW ALOFT. HOWEVER AS THE UPPER TROUGH PASSES TO OUR NORTH ON
TUESDAY...MODELS SHOW A WEAK COLD FRONT PUSHING UP AGAINST THE FRONT
RANGE AND WITH A MOIST UP SLOPE FLOW...SHOULD SEE RAIN CHANCES CREEP
UP. TEMPS ON THE PLAINS TUESDAY AS MUCH AS 4-6 DEG F COOLER. ZONAL
FLOW ON WEDNESDAY WILL DRY THINGS OUT AND LARGELY CONFINE ANY
PRECIP/T-STORMS TO THE HIGHER TERRAIN. LOOK FOR TEMPS ON WEDNESDAY
TO BE A DEG OR TWO WARMER.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 927 AM MDT THU JUL 23 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD FOR ALL AIRPORTS.
SOME MID TO HIGH LEVEL SCATTERED DECK WILL PERSIST ON AND OFF
THROUGH THE AFTERNOON WITH LIGHT TO VARIABLE WINDS FROM THE SW.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BOWEN
SHORT TERM...GIMMESTAD
LONG TERM...BAKER
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS TAUNTON MA
734 PM EDT FRI JUL 24 2015
.SYNOPSIS...
UNSETTLED WEATHER EXPECTED THROUGH EARLY NEXT WEEK...WITH MAINLY
DIURNAL SHOWERS AND THUNDERSTORMS. STRONG TO SEVERE THUNDERSTORMS
REMAIN POSSIBLE THIS EVENING...AND WILL BE POSSIBLE AGAIN SOMETIME
SUNDAY INTO MONDAY. THE NEXT MAIN WEATHER HEADLINE WILL BE A
POSSIBLE HEAT WAVE TUESDAY THROUGH THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
HIGHLIGHTS...
* STRONG TO PERHAPS A FEW SEVERE STORMS INTO EARLY EVENING
* POTENTIAL IMPACTS: HAIL/STRONG WINDS AND FREQUENT LIGHTNING
DISCUSSION...
734 PM UPDATE...
INTENSITY OF CONVECTION SHOULD START TO DIMINISH SHORTLY ACROSS
SOUTHERN NEW ENGLAND. LATEST MESOANALYSIS STILL SHOWING ABOUT
600-1200 J/KG STILL IN PLACE. LAPSE RATE TRENDS ALSO SHOW
DECREASING INSTABILITY. LATEST RUNS OF THE HRRR LOOK TO HAVE A
DECENT HANDLE ON THE TIMING AND RAINFALL POTENTIAL...ALTHOUGH IT
MAY BE A BIT TOO AGRESSIVE WITH ITS AREAL COVERAGE.
TRIED TO UPDATE THE TIMING OF THE MAIN AREAS OF SHOWERS AND
ISOLATED THUNDERSTORMS THIS EVENING. EXPECTING MOST OF THE
RAINFALL TO BE OVER ACROSS SOUTHERN NEW ENGLAND TOWARD MIDNIGHT.
PREVIOUS DISCUSSION...
COOL AIRMASS OVERSPREADS THE REGION IN THE WAKE OF THE MID LEVEL
SHORT WAVE TROUGH. AT THE SURFACE THIS WILL BE REFLECTED BY A
BACKDOOR COLD FRONT YIELDING LIGHT N-NE WINDS. COOL NIGHT WITH
WIDESPREAD 50S EXCEPT LOW TO MID 60S IN THE URBAN AREAS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SATURDAY...
MID LEVEL MEAN TROUGH OVER GEORGES BANK MOVES SEAWARD ALLOWING
HEIGHT RISES TO DEVELOP OVER NEW ENGLAND ALONG WITH FLOW BECOMING
LESS CYCLONIC AND MORE ZONAL. TYPICALLY THIS SUBSIDENCE WOULD YIELD
A DRY FORECAST. HOWEVER LEFTOVER BACKDOOR FRONT ACROSS THE REGION
MAY ACT AS A FOCUS FOR SCATTERED LOW TOP AFTERNOON SHOWERS. MOST OF
THE HI RES GUIDANCE HAS SHOWERS DEVELOPING IN THE AFTERNOON IN THE
CT RIVER VALLEY AND THEN MOVING EASTWARD INTO RI AND CENTRAL MA
LATER IN THE DAY. THIS SEEMS REASONABLE BUT WILL BE A BATTLE
BETWEEN MID LEVEL SUBSIDENCE AND LOW LEVEL CONVERGENCE. NOT
EXPECTING A WASHOUT OUT JUST A LOW RISK FOR A FEW SHOWERS.
MARITIME AIRMASS FROM BACKDOOR FRONT WILL RESULT IN A LARGE TEMP
GRADIENT ACROSS THE AREA WITH HIGHS ONLY IN THE U60S TO L70S ACROSS
EASTERN MA TO L80S IN THE CT RIVER VALLEY. MORNING SUNSHINE WILL
MIX WITH AFTERNOON CLOUDS.
SATURDAY NIGHT...
BACKDOOR FRONT LIFTS NORTH AS A WARM FRONT AND WARM ADVECTION
PATTERN BEGINS TO UNFOLD YIELDING AN INCREASED RISK FOR SHOWERS AND
T-STORMS ESPECIALLY SECOND HALF OF THE NIGHT. WARMER AND MORE HUMID
THAN PREVIOUS NIGHTS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGHLIGHTS...
* SCATTERED STRONG THUNDERSTORMS POSSIBLE SUNDAY
* HEAT WAVE POSSIBLE TUESDAY THROUGH THURSDAY
* SCATTERED STORMS POSSIBLE LATE THURSDAY
SUNDAY...STILL LOOKS LIKE IT COULD BE AN ACTIVE WEATHER DAY. 0-1
KM HELICITY VALUES REMAIN RATHER ROBUST...ALTHOUGH INSTABILITY
APPEARS TO BE LAGGING A FEW HOURS BEHIND. WITH MORNING SUNSHINE
BREAKING OUT BEHIND THE DEPARTING UPPER DISTURBANCE...RAPID
DESTABILIZATION IS EXPECTED DURING THE LATE MORNING HOURS WITH
THE GFS CONTINUING TO INDICATE SURFACE-BASED CAPES APPROACHING 3000
J/KG ACROSS MOST OF THE REGION DURING THE AFTERNOON. A WARM FRONT
WILL HAVE MOVED NORTHWARD INTO NORTH CENTRAL AND NORTHEASTERN MA
BY THE AFTERNOON.
WE ARE STILL VERY FAR AWAY AT THIS POINT...AND DO NOT WANT TO GET
TOO CARRIED AWAY. THAT SAID...WE WILL NEED TO MONITOR THE
POTENTIAL FOR MORNING CONVECTION INITIATION. EVEN IF THE WIND
SHEAR AND INSTABILITY DO NOT PHASE IN TIME AND SPACE...THERE COULD
BE ENOUGH INSTABILITY TO PRODUCE STRONG TO SEVERE THUNDERSTORMS
SUNDAY AFTERNOON. THE MAIN RISK WOULD BE ACROSS INTERIOR SOUTHERN
NEW ENGLAND.
SUNDAY NIGHT AND MONDAY...
A COLD FRONT STALLS ACROSS THE AREA. THIS IS SOMEWHAT TRICKY. THE
MAJORITY OF THE LATEST GUIDANCE DEPICTS THIS FRONT BEING SQUEEZED
BETWEEN TWO HIGH PRESSURES. AGAIN A LOT OF UNCERTAINTY AS THERE
IS A GOOD AMOUNT OF CAPE AROUND...YET THERE IS HARDLY ANY SHEAR
AS GUIDANCE SHOWS 10-20 KTS. HAVE COMPROMISED WITH SLIGHT CHANCE
POPS FOR SHOWERS OR TSTMS. HIGH TEMPERATURES FORECAST TO BE A FEW
DEGREES WARMER THAN SUNDAY...MAINLY 80 TO 85.
TUESDAY THROUGH THURSDAY...
THE COLD FRONT FINALLY GETS WASHED OUT SOMEWHERE OVER SOUTHERNMOST
NEW ENGLAND BY TUESDAY. CANNOT RULE OUT AN ISOLATED SHOWER
TUESDAY. OTHERWISE...AN UPPER LEVEL HIGH PRESSURE WILL SPREAD
FROM THE MIDWEST TOWARD NEW ENGLAND. THIS WILL TRANSLATE TO MAINLY
SUNNY CONDITIONS AND MUCH HOTTER WEATHER. IN FACT...925 MB
TEMPERATURES REACH +28C WED AND THU AFTERNOONS. WE ARE FORECASTING
NEAR 90 FOR HIGHS ON TUE AND LOWER TO MID 90S WEDNESDAY AND
THURSDAY FOR MUCH OF THE INTERIOR...COOLER AT THE COAST. IT WOULD
BE A HEAT WAVE IF WE COULD HIT 90 DEGREES FOR THREE CONSECUTIVE
DAYS.
THURSDAY EVENING INTO FRIDAY...MODELS ARE TRENDING TOWARD HAVING
A COLD FRONT MOVE THROUGH THURSDAY NIGHT INTO FRIDAY. THERE
SHOULD BE SOLID CAPPING DURING THE DAY ON THURSDAY WITH 700 MB
TEMPERATURES FORECAST TO APPROACH +10C. THIS CAP COULD ERODE
THURSDAY NIGHT INTO FRIDAY. THERE IS A CHANCE OF THUNDERSTORMS AS
THIS COLD FRONT APPROACHES.
&&
.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH SATURDAY NIGHT/...HIGH CONFIDENCE.
ANY LINGERING SHOWERS/T-STORMS DISSIPATE BY 03Z. DRY WEATHER AND
VFR PREVAIL THEREAFTER.
SATURDAY...
VFR WITH SCATTERED SHOWERS POSSIBLE ALONG A BACKDOOR FRONT ACROSS
THE INTERIOR.
SAT NIGHT...
VFR TO START BUT LOWERING TO MVFR AND LOW RISK OF IFR BY SUNDAY
MORNING IN SCATTERED SHOWERS AND FOG.
KBOS TERMINAL...ONSHORE WINDS PERSIST THRU SAT NIGHT. HIGH
CONFIDENCE ON SCT SHRA/-TSRA BUT LOWER CONFIDENCE ON SMALL AND
GUSTY WINDS. STORMS PEAK AROUND 21Z THEN DISSIPATE BY 00Z-02Z.
SCATTERED SHOWERS POSSIBLE SAT AFTN BUT THUNDER UNLIKELY.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. SHRA/TSRA SHOULD MAINLY
STAY N/E OF THE TERMINAL...BUT VCSH/VCTS IS POSSIBLE.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUNDAY INTO MONDAY...MODERATE CONFIDENCE. MVFR IN SCATTERED
SHOWERS AND THUNDERSTORMS. A FEW STRONG STORMS POSSIBLE LATE
SUNDAY MORNING THROUGH SUNDAY EVENING WITH LOCAL IFR VSBYS.
TUESDAY...MODERATE CONFIDENCE. VFR. POSSIBLE MVFR IN ISOLATED
SHOWERS OVER THE INTERIOR.
WEDNESDAY...HIGH CONFIDENCE VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...HIGH CONFIDENCE.
TONIGHT...EVENING SHOWERS AND T-STORMS...MOST NUMEROUS NEAR SHORE
WITH SMALL HAIL AND GUSTY WINDS POSSIBLE. IMPROVING CONDITIONS LATER
THIS EVENING. BACKDOOR COLD FRONT MOVES ONSHORE WITH LIGHT NORTH TO
NORTHEAST WINDS.
SATURDAY...LIGHT EAST TO SOUTHEAST WINDS. GOOD VSBY AND MAINLY DRY
WEATHER.
SAT NIGHT...SOUTHEAST WINDS WITH LOWERING VSBY IN FOG AND
SHOWERS...POSSIBLE T-STORM.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
HIGH CONFIDENCE. WINDS AND SEAS BELOW SMALL CRAFT ADVISORY LEVELS
THROUGH THIS PERIOD AS WEAK PRESSURE GRADIENT PERSISTS ACROSS
WATERS.
WARM FRONT LIFTS N ACROSS THE WATERS EARLY SUNDAY. A SLOW-MOVING
COLD FRONT APPROACHES THE WATERS MONDAY INTO TUESDAY...BUT MAY
DISSIPATE BY TUESDAY.
A FEW STRONG THUNDERSTORMS ARE POSSIBLE OVER THE WATERS SUNDAY
INTO SUNDAY EVENING.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BELK/NOCERA
NEAR TERM...BELK/NOCERA
SHORT TERM...NOCERA
LONG TERM...BELK
AVIATION...BELK/NOCERA
MARINE...BELK/NOCERA
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
122 AM EDT THU JUL 23 2015
.PREV DISCUSSION... /ISSUED 802 PM EDT WED JUL 22 2015/
UPDATE...
EVENING CONVECTION WILL CONTINUE FOR THE NEXT SEVERAL HOURS.
UPDATED POPS EARLIER TO REFLECT THE CURRENT RADAR AND HRRR TRENDS.
MAIN UPDATE IS TO REMOVE THE HEAT ADVISORY.
PREV DISCUSSION... /ISSUED 257 PM EDT WED JUL 22 2015/
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
SHORT TERM /TODAY THROUGH THURSDAY/... CURRENT RADAR LOOP SHOWS
SHOWERS WITH SOME ISOLATED THUNDERSTORMS MOVING INTO NW GA. WEAK
WEST TO NORTHWEST FLOW IS STILL EXPECTED TO BECOME A LITTLE MORE
ACTIVE OVER THE NEXT 24 HOURS. EXCEPTING TO SEE MORE AREAL COVERAGE
TODAY THAN YESTERDAY WITH THE PRECIPITATION BUT THURSDAY APPEARS TO
BE OUR MOT ACTIVE DAY. DEEPER MOISTURE OVER TN WILL CONTINUE TO SINK
SOUTH INTO GA THROUGH THU AFTERNOON BRINGING A STRONGER SHORT WAVE
AND LIKELY POPS TO THE STATE. ALSO EXPECTING INCREASED INSTABILITY
SO THE MARGINAL RISK AREA SPC HAS OVER ALMOST THE ENTIRE STATE FOR
DAY 2 STILL LOOKS GOOD. PERSISTENCE ON TEMPS ACROSS CENTRAL GA
LOOKS GOOD WITH SLIGHTLY COOLER TEMPS ACROSS NORTH GA. COOLER TEMPS
CWA WIDE ON THURSDAY DUE TO ADDITIONAL CLOUDS AND PRECIP.
01
LONG TERM /FRIDAY THROUGH WEDNESDAY/...
NOT MANY CHANGES TO THE PREVIOUS LONG TERM FORECAST. FOR FRIDAY...LARGE
SCALE SYNOPTIC PATTERN WILL BE DOMINATED BY BROAD MID-LEVEL
RIDGING OVER THE SOUTHERN PLAINS...SUPPORTING NORTHWEST FLOW
ALOFT ACROSS THE SOUTHEAST US. A WEAK DISTURBANCE WITHIN THIS
FLOW WILL INTERACT WITH A NEARLY STATIONARY SURFACE BOUNDARY TO
PROVIDE A FOCUS FOR CONVECTIVE DEVELOPMENT...PARTICULARLY ACROSS
THE CENTRAL PORTION OF THE CWA DURING THE AFTERNOON. MEANWHILE...DRIER
AIR WILL BEGIN TO FILTER INTO THE NORTHERN PORTION OF THE CWA.
SATURDAY AND SUNDAY...RELATIVELY TRANQUIL WEATHER EXPECTED AS
SURFACE HIGH PRESSURE RIDGES DOWN THE SPINE OF THE APPALACHIANS
AND H5 RIDGE BEGINS TO BUILD SLIGHTLY EAST OVER THE SOUTHEAST.
RELATIVELY DRIER AIR /PW VALUES 1-1.50INCHES/ SHOULD SUPPRESS
WIDESPREAD CONVECTION...BUT CANNOT RULE OF A FEW DIURNALLY
ENHANCED THUNDERSTORMS WITH THE CONTINUED WARM TEMPERATURES.
MONDAY THROUGH WEDNESDAY...EXPECT A GRADUAL INCREASE IN MOISTURE
DURING THIS PERIOD. POTENT TROUGH MOVING ACROSS NORTHERN ROCKIES
WILL FLATTEN THE PERSISTENT H5 RIDGE AND GENERATE MINOR
PERTURBATIONS IN THE MID LEVEL FLOW PATTERN. GFS AND ECMWF
BOTH INDICATE RIDGE WILL SUPPRESS WIDESPREAD PRECIPITATION FOR
THE MOST PART MONDAY AND TUESDAY...BUT DO EXPECT THESE
DISTURBANCES TO AFFECT THE AREA BY MID WEEK. THEREFORE...EXPECT
POPS TO INCREASE BY WEDNESDAY. WILL ALSO CONTINUE TO MONITOR THE
POTENTIAL FOR A PSUEDO-TROPICAL DISTURBANCE DEVELOPING OFF THE
EAST COAST OF FLORIDA AT THE END OF THE PERIOD...AS INDICATED BY
THE ECMWF.
KOVACIK
&&
.AVIATION...
06Z UPDATE...
VFR CONDITIONS WILL REMAIN THROUGH THE FORECAST. THE EXCEPTION
WILL BE EARLY THIS MORNING IN AHN/MCN WHERE LIGHT FOG COULD REDUCE
VSBYS TO 3-5SM. A FEW SHOWERS REMAIN POSSIBLE OVER THE FORECAST
AREA EARLY THIS MORNING BUT COVERAGE SHOULD INCREASE THIS MORNING
WITH WIDESPREAD SHRA/TSRA THIS AFTERNOON. COVERAGE SHOULD
DISSIPATE SOMEWHAT TONIGHT. WINDS WILL REMAIN WESTERLY...INCREASE
TO NEAR 10KTS BY AFTERNOON WITH A FEW GUSTS...HOWEVER GUSTS IN
TSRA COULD REACH 30 TO 35 KTS.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON TIMING OF TSRA
HIGH ON REMAINING ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 90 73 91 73 / 70 60 40 30
ATLANTA 88 73 90 75 / 70 60 30 20
BLAIRSVILLE 84 66 85 67 / 70 60 30 20
CARTERSVILLE 86 73 90 73 / 70 60 30 20
COLUMBUS 92 75 93 77 / 60 60 40 30
GAINESVILLE 89 72 88 72 / 70 60 30 20
MACON 93 75 93 75 / 60 60 40 40
ROME 88 72 91 72 / 70 60 30 20
PEACHTREE CITY 89 73 90 73 / 70 60 30 30
VIDALIA 95 76 93 75 / 60 60 50 50
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...17
LONG TERM....BDL
AVIATION...17
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
310 PM EDT THU JUL 23 2015
.SYNOPSIS...
ISSUED AT 436 AM EDT THU JUL 23 2015
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO PROVIDE TRANQUIL WEATHER
TO THE REGION THROUGH FRIDAY. CHANCES OF SHOWERS AND THUNDERSTORMS
WILL INCREASE FOR SATURDAY AND SUNDAY AS AN UPPER LEVEL
DISTURBANCE SKIRTING ACROSS THE NORTHERN TIER OF THE UNITED STATES
DRAGS A FRONTAL BOUNDARY INTO THE REGION. HIGH TEMPERATURES THIS
AFTERNOON WILL REACH INTO THE LOWER 80S WITH LOW TEMPERATURES
TONIGHT DROPPING BACK INTO THE LOWER 60S.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 309 PM EDT THU JUL 23 2015
SURFACE ANALYSIS DEPICTS HIGH PRESSURE CENTERED OVER THE SOUTHERN
GREAT LAKES/MIDWEST REGION. WATER VAPOR IMAGERY AND RAP ANALYSIS
SHOWING WEAK DISTURBANCE MOVING DOWN INTO GREAT LAKES REGION IN NW
FLOW AND VIS SAT SHOWING EXTENSIVE DIURNAL CU FIELD OVER MUCH OF
THE FORECAST AREA THIS AFTERNOON. SURFACE HIGH PRESSURE WILL
CONTINUE TO DOMINATE THE REGION RESULTING IN PLEASANT SEASONABLE
WEATHER IN THE SHORT TERM. HIGH PRESSURE CENTER WILL DRIFT SLOWLY
EASTWARD ON FRIDAY AND UPPER LEVEL RIDGING WILL ALSO PUSH INTO THE
REGION WHICH WILL TREND OUR AREA TOWARD WARMER AND MORE HUMID
CONDITIONS. EXPECT TEMPS TO BE NEAR NORMAL FOR LOWS TONIGHT AND
GOING SLIGHTLY ABOVE NORMAL FOR HIGHS ON FRIDAY.
&&
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 309 PM EDT THU JUL 23 2015
COLD FRONT...TIED TO SHORTWAVE ENERGY FLATTENING A SOUTH-CENTRAL US
RIDGE INTO THE GREAT LAKES REGION...WILL WEAKEN SSE INTO THE LOCAL
AREA ON SATURDAY. BETTER MID/UPPER LEVEL FORCING LIKELY PASSES NORTH
AND WANES BY PEAK HEATING...THOUGH FOLD OVER OF LOW LEVEL THETA-E
RIDGE AND NEAR 70F SFC DEWPOINTS SUGGEST POTENTIAL FOR MODERATE
BOUNDARY LAYER DESTABILIZATION ALONG THE MAIN FRONT OR LEADING
CONVECTIVE OUTFLOW BY MID AFTN-EARLY EVE. AS A RESULT THE POTENTIAL
DOES EXIST FOR ISOLATED TO SCATTERED THUNDERSTORMS ALONG THIS
FRONTAL ZONE...WITH AN ISOLATED STRONG STORM POSSIBLE GIVEN
EXPECTATIONS FOR 25-35 KNOTS OF 0-6 KM SHEAR ON SOUTHERN FRINGE OF
MID LEVEL JET WORKING THROUGH THE CENTRAL GREAT LAKES.
LEFTOVER BAROCLINIC ZONE/INSTABILITY GRADIENT LOOKS TO STALL JUST
SSW OF THE FORECAST AREA BY LATER SATURDAY NIGHT THROUGH MONDAY.
SEVERAL LOW AMPLITUDE/CONVECTIVELY AIDED SHORTWAVES EMBEDDED IN WEAK
WNW FLOW WILL HELP FOCUS SEVERAL CONVECTIVE CLUSTERS IN THE VICINITY
OF THIS FEATURE. THIS PLACES AREAS MAINLY ALONG/SOUTHWEST OF THE US
30 CORRIDOR IN INDIANA FOR BETTER SHOWER/STORM CHANCES INTO EARLY
NEXT WEEK.
MEDIUM RANGE MODELS REMAINED IN GOOD AGREEMENT IN UPPER RIDGE
BUILDING NE INTO THE REGION LATER MONDAY THROUGH EARLY WEDNESDAY IN
ADVANCE OF RENEWED WESTERN CONUS TROUGHING. THIS SHOULD ALLOW HIGHER
HUMIDITY/WARMER TEMPS TO BUILD IN BEFORE ANOTHER STRONGER COLD FRONT
DRIVES THROUGH BY LATER WEDNESDAY OR THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED
AT 100 PM EDT THU JUL 23 2015
VFR THRU THIS TAF CYCLE AS HIGH PRESSURE CONTINUES TO DOMINATE. SAVE
FOR A FEW DIURNAL CU WEST OF KSBN ALONG LAKE BREEZE AND STRAY ALTOCU
IN VICINITY OF KFWA EXPECT CLEAR SKIES TO PREVAIL. WILL BEGIN KSBN
WITH LIGHT NW WIND ON LAKE BREEZE...OTHERWISE LIGHT AND VARIABLE AT
BOTH SITES.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...LOGSDON
LONG TERM...STEINWEDEL
AVIATION...LOGSDON
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS TOPEKA KS
254 PM CDT THU JUL 23 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 230 PM CDT THU JUL 23 2015
QUIET AFTERNOON AND EVENING IN STORE FOR THE AREA. THE CUMULUS
FIELD WILL LIKELY DISSIPATE LATER THIS EVENING AND WINDS REMAIN
OUT OF THE EAST SOUTHEAST. CURRENT OBSERVATIONS SHOW A BOUNDARY
ACROSS WESTERN NE WITH TOWERING CUMULUS ALREADY DEVELOPING. SOME
OF THE MODELS ARE HINTING AT ISOLATED TO SCATTERED STORMS FORMING
ALONG THIS BOUNDARY AS IT GRADUALLY MOVES EASTWARD. THESE STORMS
MAY ONLY REACH NORTH CENTRAL KS AND SOUTH CENTRAL NE BEFORE
WEAKENING. ONLY THE MOST RECENT RUNS OF THE HRRR KEEP THIS
ACTIVITY GOING INTO CENTRAL KS. THERE IS A LOW LEVEL JET FORECAST
TO STRENGTHEN TONIGHT OVER CENTRAL KS THAT VEERS THROUGH OUT THE
MORNING HOURS. ISENTROPIC LIFT LOOKS TO DEVELOP OVER PORTIONS OF
EASTERN KS ALTHOUGH THE SOUNDINGS SHOW RATHER DRY AIR WHERE THE
LIFT IS MAXIMIZED. THE BETTER MOISTURE AND ISENTROPIC LIFT APPEARS
TO BE FAR SOUTHEAST KS. THIS GIVES ME LOW CONFIDENCE IN ANY
SHOWERS OR STORMS FORMING TONIGHT. HAVE GONE WITH SLIGHT POPS FOR
NOW TO ACCOUNT FOR WESTERN NE CONVECTION REACHING THE AREA AND OR
ELEVATED PRECIP FORMING DURING THE EARLY MORNING HOURS. THE
ELEVATED WARM LAYER WILL STRENGTHEN AS WELL AS 850 MB TEMPS REACH
25-30 C BY TOMORROW AFTERNOON. SURFACE WINDS GRADUALLY VEER AS THE
FRONT APPROACHES FROM THE NORTHWEST. DEW POINTS STAY IN THE MID TO
UPPER 70S WITH THE HIGHEST VALUES IN FAR EASTERN KS. THE ONLY
CONCERN IS THAT SOME OF THE MODELS SHOW DEEPER MIXING IN CENTRAL
KS THAT NOSES INTO THE WESTERN FORECAST AREA. THIS COULD CAUSE THE
DEW POINTS TO DECREASE DURING PEAK HEATING BUT WILL KEEP THE
TEMPERATURES ABOVE 100. REGARDLESS IT APPEARS THE MOST OF THE AREA
WILL SEE HEAT INDICES RANGE FROM 106-111, WHICH HAS PROMPTED A
HEAT ADVISORY FOR TOMORROW.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 230 PM CDT THU JUL 23 2015
SATURDAY AND SUNDAY...ONLY MADE SMALL ADJUSTMENTS TO PREVIOUS
PRECIP FORECAST. CONVECTION ROLLING OFF THE HIGH PLAINS SATURDAY
NIGHT MOVES EASTWARD ALONG THE FRONTAL BOUNDARY TRAILING ACROSS
THE NORTHERN PART OF THE STATE THANKS TO THE SHORTWAVE MOVING INTO
THE GREAT LAKES. LLJ FOCUSES A LITTLE BETTER TO THE WEST BEFORE
VEERING WITH TIME AND CONVERGING ACROSS THE NORTHERN COUNTIES.
WILL HAVE TO BATTLE AGAINST PERSISTENT CAP AT 700MB. WITH THIS
PATTERN WOULD ANTICIPATE STORMS TO MOVE ALONG THE PERIPHERY AND
WILL DRAW UP RAIN CHANCES AS SUCH. NAM AND GFS BRING A SECONDARY
SHORTWAVE OUT OF THE WEST LATER IN THE DAY SATURDAY...WITH A
LITTLE STRONGER LLJ INTO THE OVERNIGHT HOURS. WOULD LIKELY SEE A
BREAK IN PRECIP IN THE MID TO LATE DAY BEFORE STORMS COME IN FROM
THE WEST INTO THE OVERNIGHT HOURS...ONCE AGAIN FOCUSING BETTER TO
THE NORTH. AS THIS WAVE PASSES TO THE EAST...THE RIDGE ALOFT
AMPLIFIES IN ITS WAKE...AND WILL MOST LIKELY BRING AN END TO RAIN
CHANCES LATER IN THE DAY ON SUNDAY. HAVE DROPPED TO JUST A SLIGHT
CHANCE ON SUNDAY. CHANCES FOR RAIN AND ASSOCIATED CLOUD COVER AND
COOLER OUTFLOWS WILL HAVE PERIODIC IMPACTS ON THE HEAT...HOWEVER
FOR SATURDAY BETWEEN SYSTEMS THINK ITS A GOOD BET THAT HEAT
INDICIES WILL RISE BACK TO ADVISORY LEVELS OVER THE SOUTHERN PARTS
OF THE CWA...BUT THE NORTHERN COUNTIES COULD CATCH MORE OF A
BREAK. NOT EXTENDING THE ADVISORY PRODUCT AT THIS TIME, BUT WILL
LIKELY NEED TO BE FOR AT LEAST PART OF THE AREA FOR THE DAY ON
SATURDAY. THINK SUNDAY WILL HAVE MORE IMPACT FROM CONVECTION NEAR
THE AREA...AND DON`T CURRENTLY HAVE ADVISORY INDICES IN THE
FORECAST.
MONDAY-THURSDAY...UPPER LONGWAVE TROF MOVING INTO THE NORTHERN
ROCKIES LATE MONDAY HELPS STRENGTHEN THE RIDGE ACROSS THE PLAINS
BRINGING ANOTHER FEW HOT DAYS FOR MONDAY AND TUESDAY. NEXT FRONT
ASSOCIATED WITH THAT UPPER TROF MOVES INTO THE CENTRAL PLAINS ON
WEDNESDAY...BRINGING A SLIGHTLY BETTER CHANCE FOR RAIN FOLLOWED BY
POTENTIALLY A NICE COOL DOWN BY LATE WEDNESDAY INTO THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1232 PM CDT THU JUL 23 2015
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. THERE IS A SLIGHT
CHANCE FOR AN ISOLATED SHOWER AROUND SUNRISE TOMORROW.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM NOON TO 8 PM CDT FRIDAY FOR KSZ008>012-
020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...SANDERS
LONG TERM...67
AVIATION...SANDERS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
229 PM CDT THU JUL 23 2015
...UPDATED LONG TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 1259 PM CDT THU JUL 23 2015
AN UPPER LEVEL DISTURBANCE WILL CROSS NORTHERN KANSAS EARLY THIS
EVENING AS A SURFACE WARM FRONT LIFTS NORTH ACROSS WESTERN KANSAS.
NORTH OF THIS BOUNDARY SURFACE DEWPOINTS THIS MORNING WERE IN THE
UPPER 60S TO LOWER 70S. BASED ON THE EXPECTED LOCATION OF THIS
BOUNDARY EARLY THIS EVENING ALONG WITH WHERE THE BETTER MOISTURE
AND INSTABILITY WILL BE AROUND 00Z FRIDAY AHEAD OF THE UPPER LEVEL
DISTURBANCE WILL CONTINUE TO FAVOR KEEPING SOME ISOLATED TO WIDELY
SCATTERED THUNDERSTORMS LATE TODAY AND EARLY THIS EVENING NORTH OF
ROUGHLY HIGHWAY 96. SIMILAR TO LAST NIGHT THE BETTER CHANCES FOR
CONVECTION WILL BE AFTER SUNSET AS WARM AIR ADVECTION IMPROVES AND
BETTER 700MB TO 500MB LAPSE RATES DEVELOP AS THE UPPER LEVEL
DISTURBANCE CROSSES WESTERN KANSAS. HEAVY RAINFALL AND GUSTY WINDS
WILL BE THE MAIN HAZARD FROM ANY STORM THAT DOES CROSS NORTHERN
KANSAS EARLY TONIGHT.
850MB TEMPERATURES WARM ROUGHLY 2-3C BETWEEN 00Z FRIDAY AND 00Z
SATURDAY. BASED ON THIS WARMING TREND AND THE EXPECTED HIGHS LATER
TODAY THE PREVIOUS FORECAST STILL LOOKS ON TRACK WITH TEMPERATURES
CLIMBING TO AROUND 100 DEGREES FRIDAY AFTERNOON. THIS COMBINED
WITH AFTERNOON DEWPOINTS IN THE LOW TO MID 60S WILL YIELD HEAT
INDEX VALUES OF 100 TO AROUND 105. THE HIGHER VALUES FRIDAY
AFTERNOON WILL ROUGHLY BE ALONG AND EAST OF HIGHWAY 183. BASED ON
WHERE THESE HIGHER HEAT INDEX READINGS ARE EXPECTED WILL BE
ISSUING A HEAT ADVISORY FOR PORTIONS OF NORTH CENTRAL AND SOUTH
CENTRAL KANSAS FRIDAY AFTERNOON.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 227 PM CDT THU JUL 23 2015
A COLD FRONT/SURFACE BOUNDARY WILL DROP SOUTH ACROSS WESTERN
KANSAS LATE FRIDAY NIGHT AS ANOTHER UPPER LEVEL TROUGH CROSSES THE
CENTRAL HIGH PLAINS. GIVEN THE LOCATION OF THIS FRONTAL BOUNDARY
FRIDAY NIGHT AND THE MID LEVEL INSTABILITY AHEAD OF THIS NEXT
UPPER LEVEL SYSTEM WILL KEEP THE BETTER CHANCES FOR OVERNIGHT
CONVECTION ACROSS NORTH CENTRAL AND WEST CENTRAL KANSAS.
OVER THE WEEKEND PERIOD THE BETTER CHANCE FOR THUNDERSTORMS STILL
APPEAR TO BE LATE SATURDAY THROUGH EARLY SUNDAY AS ANOTHER,
STRONGER UPPER LEVEL TROUGH CROSSES THE CENTRAL PLAINS. AT THIS
TIME CONFIDENCE IS NOT HIGH ON TIMING OF THIS LATE SATURDAY UPPER
LEVEL FEATURE SO AM LEANING TOWARDS STAYING CLOSE TO THE PREVIOUS
FORECAST ON TIMING OF PRECIPITATION. DESPITE A COLD FRONT MOVING
INTO SOUTHWEST KANSAS OVER THE WEEKEND TEMPERATURES WILL STAY ON
THE WARM SIDE. HIGHS BOTH SATURDAY AND SUNDAY WILL BE IN THE MID
TO UPPER 90S.
EARLY NEXT WEEK THE UPPER HIGH LOCATED OVER THE SOUTHERN PLAINS
WILL BEGIN TO MOVE EAST/NORTHEAST, AND AN UPPER TROUGH WILL MOVE
ACROSS THE WESTERN UNITED STATES. SOME TROPICAL MOISTURE WILL BE
RETURNING TO THE CENTRAL HIGH PLAINS EARLY NEXT WEEK AS A
SOUTHWESTERLY FLOW IMPROVES. GIVEN THIS ALONG WITH ANY SUBTLE WAVE
EMBEDDED IN THE SOUTHWEST FLOW THERE WILL BE A CHANCE/SLIGHT
CHANCE FOR LATE DAY OR OVERNIGHT THUNDERSTORMS EARLY NEXT WEEK.
THE BETTER OPPORTUNITY WILL BE TOWARDS MID WEEK BASED ON TIMING OF
THE NEXT COLD FRONT RETURNING TO WESTERN KANSAS AND THE TRACK OF
THE UPPER LEVEL TROUGH AS IT CROSSES THE ROCKIES AND MOVES OUT
INTO THE NORTHERN AND CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1210 PM CDT THU JUL 23 2015
A WARM FRONT WILL LIFT NORTH ACROSS SOUTHWEST KANSAS TODAY AND
NORTH CENTRAL KANSAS LATE TONIGHT. AS THIS SURFACE BOUNDARY PASSES
A SOUTHEAST WIND AT 10 TO NEAR 15 KNOTS WILL SHIFT TO THE SOUTH
SOUTHWEST. BUFR SOUNDINGS AND HRRR BOTH INDICATED VFR CONDITIONS
THIS AFTERNOON AND TONIGHT. AREAS OF IFR CONDITIONS FROM STRATUS
AND MVFR VISIBILITIES FROM EARLY MORNING FOG WILL BE POSSIBLE
NORTH OF THE WARM FRONT. AT THIS TIME GIVEN WHERE THIS SURFACE
BOUNDARY IS FORECAST TO BE LOCATED AROUND 12Z FRIDAY BY SEVERAL
MODELS WILL TREND TOWARDS LOWER CEILINGS AND VISIBILITIES IN THE
HYS AREA FOR SEVERAL HOURS AROUND DAYBREAK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 73 101 73 100 / 10 10 20 40
GCK 72 101 71 98 / 10 10 20 40
EHA 70 99 70 99 / 10 20 20 30
LBL 72 100 72 100 / 10 10 10 30
HYS 74 102 74 96 / 20 20 30 40
P28 76 102 76 101 / 10 10 10 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM NOON TO 8 PM CDT FRIDAY FOR KSZ031-046-065-
066-081-090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...BURGERT
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
101 PM CDT THU JUL 23 2015
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 1259 PM CDT THU JUL 23 2015
AN UPPER LEVEL DISTURBANCE WILL CROSS NORTHERN KANSAS EARLY THIS
EVENING AS A SURFACE WARM FRONT LIFTS NORTH ACROSS WESTERN KANSAS.
NORTH OF THIS BOUNDARY SURFACE DEWPOINTS THIS MORNING WERE IN THE
UPPER 60S TO LOWER 70S. BASED ON THE EXPECTED LOCATION OF THIS
BOUNDARY EARLY THIS EVENING ALONG WITH WHERE THE BETTER MOISTURE
AND INSTABILITY WILL BE AROUND 00Z FRIDAY AHEAD OF THE UPPER LEVEL
DISTURBANCE WILL CONTINUE TO FAVOR KEEPING SOME ISOLATED TO WIDELY
SCATTERED THUNDERSTORMS LATE TODAY AND EARLY THIS EVENING NORTH OF
ROUGHLY HIGHWAY 96. SIMILAR TO LAST NIGHT THE BETTER CHANCES FOR
CONVECTION WILL BE AFTER SUNSET AS WARM AIR ADVECTION IMPROVES AND
BETTER 700MB TO 500MB LAPSE RATES DEVELOP AS THE UPPER LEVEL
DISTURBANCE CROSSES WESTERN KANSAS. HEAVY RAINFALL AND GUSTY WINDS
WILL BE THE MAIN HAZARD FROM ANY STORM THAT DOES CROSS NORTHERN
KANSAS EARLY TONIGHT.
850MB TEMPERATURES WARM ROUGHLY 2-3C BETWEEN 00Z FRIDAY AND 00Z
SATURDAY. BASED ON THIS WARMING TREND AND THE EXPECTED HIGHS LATER
TODAY THE PREVIOUS FORECAST STILL LOOKS ON TRACK WITH TEMPERATURES
CLIMBING TO AROUND 100 DEGREES FRIDAY AFTERNOON. THIS COMBINED
WITH AFTERNOON DEWPOINTS IN THE LOW TO MID 60S WILL YIELD HEAT
INDEX VALUES OF 100 TO AROUND 105. THE HIGHER VALUES FRIDAY
AFTERNOON WILL ROUGHLY BE ALONG AND EAST OF HIGHWAY 183. BASED ON
WHERE THESE HIGHER HEAT INDEX READINGS ARE EXPECTED WILL BE
ISSUING A HEAT ADVISORY FOR PORTIONS OF NORTH CENTRAL AND SOUTH
CENTRAL KANSAS FRIDAY AFTERNOON.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 248 AM CDT THU JUL 23 2015
THE UPPER LEVEL HIGH WILL CONTINUE TO SIT OVER THE SOUTHERN
PLAINS FRIDAY THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH UPPER
LEVEL SHORTWAVES MOVING UP AND OVER THIS FEATURE. THIS WILL BRING
PERIODIC BURSTS OF ENHANCED LIFT ACROSS WESTERN KANSAS. THE FIRST
SHORTWAVE PASSES OVER NEBRASKA FRIDAY NIGHT WITH CHANCES OF
THUNDERSTORMS ACROSS NORTHERN AND NORTH CENTRAL KANSAS. THE SECOND
PASSES FARTHER SOUTH ACROSS KANSAS AND NEBRASKA SATURDAY AFTERNOON
INTO SATURDAY NIGHT. THIS WILL BRING A BETTER CHANCE OF
THUNDERSTORMS ACROSS ALL OF WESTERN KANSAS. SKIES LOOK TO BE
PARTLY CLOUDY EACH DAY WITH THE EXCEPTION OF WHEN STORMS ARE
PRESENT. WINDS WILL GENERALLY BE FROM A SOUTHERLY DIRECTION FRIDAY
THROUGH SATURDAY NIGHT AS A TROUGH OF LOW PRESSURE CONTINUES
AROUND THE KS/CO BORDER. THUNDERSTORM CHANCES CONTINUE SUNDAY
THOUGH THE FIRST PART OF NEXT WEEK AS ADDITIONAL SHORTWAVES MOVE
THROUGH OR NORTH OF THE FORECAST AREA. SOUTHERLY WINDS CONTINUE
THROUGH MONDAY THEN COULD SHIFT TO MORE OF A NORTHERLY DIRECTION
MONDAY NIGHT INTO TUESDAY AS A COLD FRONT PASSES THROUGH THE AREA.
SKIES THROUGH THIS PERIOD ARE EXPECTED TO BE PARTLY CLOUDY WITH
THE EXCEPTION OF ABOVE AND AROUND THUNDERSTORM ACTIVITY.
AS FOR TEMPERATURES, HIGHS WILL REMAIN ABOVE NORMAL WITH HIGHS IN
THE 100-105 RANGE FRIDAY WITH UPPER 90S EXPECTED SATURDAY THROUGH
MONDAY. TEMPERATURES COOL SLIGHTLY TUESDAY INTO WEDNESDAY BEHIND
THE AFOREMENTIONED COLD FRONT. HIGH DEWPOINTS WILL ALSO REMAIN
ACROSS THE AREA FRIDAY AND A HEAD ADVISORY MAY BE NEED TO BE
ISSUED ACROSS CENTRAL AND SOUTH CENTRAL KANSAS FRIDAY AFTERNOON AS
HEAT INDICES LOOK TO REACH ABOVE 105 DEGREES. LOWS WILL ALSO
REMAIN ABOVE NORMAL WITH OVERNIGHT TEMPERATURES RANGING FROM THE
UPPER 60S ACROSS WEST CENTRAL KANSAS TO MID 70S ACROSS SOUTH
CENTRAL KANSAS FRIDAY NIGHT THROUGH MONDAY NIGHT. LOWS THEN
DECREASE A FEW DEGREES AS WE HEAD INTO THE MID PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1210 PM CDT THU JUL 23 2015
A WARM FRONT WILL LIFT NORTH ACROSS SOUTHWEST KANSAS TODAY AND
NORTH CENTRAL KANSAS LATE TONIGHT. AS THIS SURFACE BOUNDARY PASSES
A SOUTHEAST WIND AT 10 TO NEAR 15 KNOTS WILL SHIFT TO THE SOUTH
SOUTHWEST. BUFR SOUNDINGS AND HRRR BOTH INDICATED VFR CONDITIONS
THIS AFTERNOON AND TONIGHT. AREAS OF IFR CONDITIONS FROM STRATUS
AND MVFR VISIBILITIES FROM EARLY MORNING FOG WILL BE POSSIBLE
NORTH OF THE WARM FRONT. AT THIS TIME GIVEN WHERE THIS SURFACE
BOUNDARY IS FORECAST TO BE LOCATED AROUND 12Z FRIDAY BY SEVERAL
MODELS WILL TREND TOWARDS LOWER CEILINGS AND VISIBILITIES IN THE
HYS AREA FOR SEVERAL HOURS AROUND DAYBREAK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 73 101 73 / 20 10 10 20
GCK 99 72 101 71 / 10 10 10 20
EHA 98 70 99 70 / 10 10 20 20
LBL 100 72 100 72 / 10 10 10 10
HYS 96 74 102 74 / 20 20 20 30
P28 98 76 102 76 / 50 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 1 PM TO 8 PM CDT FRIDAY FOR KSZ031-046-065-
066-081-090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1212 PM CDT THU JUL 23 2015
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1210 PM CDT THU JUL 23 2015
AT 12Z THURSDAY AN UPPER LEVEL TROUGH EXTENDED FROM THE PACIFIC
NORTHWEST TO JUST OFF THE CENTRAL CALIFORNIA COAST. AN UPPER LEVEL
250MB JET EXTENDED FROM THE BASE OF THIS UPPER TROUGH TO NORTHERN
UTAH. FURTHER EAST AN UPPER LEVEL RIDGE AXIS WAS LOCATED OVER THE
CENTRAL AND NORTHERN PLAINS. ACROSS THE SOUTHWEST UNITED STATES
SEVERAL UPPER LEVEL DISTURBANCES WERE EVIDENT EMBEDDED IN THE
SOUTH TO SOUTHWESTERLY FLOW. ONE OF THESE UPPER WAVES AT 12Z
THURSDAY WERE LOCATED OVER EASTERN COLORADO. A 700MB BAROCLINIC
ZONE WAS LOCATED ACROSS KANSAS AND NEBRASKA THIS MORNING.
TEMPERATURES VARIED FROM +9C AT OMAHA TO +12C AT DODGE CITY AND
+13C WAS REPORTED AT NORTH PLATTE. A SURFACE WARM FRONT EXTENDED
FROM SOUTHEAST COLORADO TO WESTERN OKLAHOMA. JUST NORTH OF THIS
FRONT EARLIER THIS MORNING A SOUTHEASTERLY FLOW WAS OBSERVED
ACROSS SOUTHWESTERN KANSAS WITH DEWPOINTS IN THE UPPER 60S TO
LOWER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 248 AM CDT THU JUL 23 2015
ABOVE NORMAL TEMPERATURES AND DEWPOINTS WILL CONTINUE TODAY
THROUGH TONIGHT AS MID LEVEL TEMPERATURES REMAIN WARM. A LARGE
UPPER LEVEL HIGH SITS ABOVE THE SOUTHERN PLAINS WITH SHORTWAVES
MOVING AROUND ITS PERIPHERY. MOSTLY CLEAR SKIES ARE ANTICIPATED
THIS MORNING WITH A FEW CUMULUS CLOUDS FORMING IN THE AFTERNOON.
WINDS WILL GENERALLY BE FROM A SOUTHERLY DIRECTION TODAY AS A
TROUGH OF LOW PRESSURE CONTINUES ACROSS EASTERN COLORADO. HIGHS IN
THE UPPER 90S TO AROUND 100 DEGREES ARE ANTICIPATED BY MID
AFTERNOON WITH DEWPOINTS RANGING FROM THE UPPER 60S ACROSS WESTERN
PORTIONS OF THE CWA TO LOWER 70S ACROSS THE EASTERN PORTIONS OF
THE CWA. THE WARM TEMPERATURES IN COMBINATION OF THE HIGH
DEWPOINTS WILL CAUSE HEAT INDICES TO SHOOT AROUND OR ABOVE 100
DEGREES, ESPECIALLY ACROSS SOUTH CENTRAL KANSAS. HEAT INDICES
APPROACH HEAT ADVISORY CRITERIA ACROSS SOUTH CENTRAL KANSAS THIS
AFTERNOON BUT WILL REFRAIN FROM ISSUING AS THE HIGHEST APPARENT
TEMPERATURE VALUE DISPLAYED IS 104 DEGREES. AS FOR TONIGHT, A FEW
THUNDERSTORMS MAY BE POSSIBLE ACROSS NORTH AND NORTH CENTRAL
KANSAS, HOWEVER, I BELIEVE THAT THIS ACTIVITY SHOULD STAY OUT OF
THE FORECAST AREA. LOWS OVERNIGHT LOOK TO RANGE FROM THE UPPER 60S
ACROSS WEST CENTRAL KANSAS TO MID 70S ACROSS SOUTH CENTRAL KANSAS.
SOUTHERLY WINDS CONTINUE OVERNIGHT AS THE PERSISTENT TROUGH OF LOW
PRESSURE SITS AROUND THE KS/CO BORDER.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 248 AM CDT THU JUL 23 2015
THE UPPER LEVEL HIGH WILL CONTINUE TO SIT OVER THE SOUTHERN
PLAINS FRIDAY THROUGH AT LEAST THE MIDDLE OF NEXT WEEK WITH UPPER
LEVEL SHORTWAVES MOVING UP AND OVER THIS FEATURE. THIS WILL BRING
PERIODIC BURSTS OF ENHANCED LIFT ACROSS WESTERN KANSAS. THE FIRST
SHORTWAVE PASSES OVER NEBRASKA FRIDAY NIGHT WITH CHANCES OF
THUNDERSTORMS ACROSS NORTHERN AND NORTH CENTRAL KANSAS. THE SECOND
PASSES FARTHER SOUTH ACROSS KANSAS AND NEBRASKA SATURDAY AFTERNOON
INTO SATURDAY NIGHT. THIS WILL BRING A BETTER CHANCE OF
THUNDERSTORMS ACROSS ALL OF WESTERN KANSAS. SKIES LOOK TO BE
PARTLY CLOUDY EACH DAY WITH THE EXCEPTION OF WHEN STORMS ARE
PRESENT. WINDS WILL GENERALLY BE FROM A SOUTHERLY DIRECTION FRIDAY
THROUGH SATURDAY NIGHT AS A TROUGH OF LOW PRESSURE CONTINUES
AROUND THE KS/CO BORDER. THUNDERSTORM CHANCES CONTINUE SUNDAY
THOUGH THE FIRST PART OF NEXT WEEK AS ADDITIONAL SHORTWAVES MOVE
THROUGH OR NORTH OF THE FORECAST AREA. SOUTHERLY WINDS CONTINUE
THROUGH MONDAY THEN COULD SHIFT TO MORE OF A NORTHERLY DIRECTION
MONDAY NIGHT INTO TUESDAY AS A COLD FRONT PASSES THROUGH THE AREA.
SKIES THROUGH THIS PERIOD ARE EXPECTED TO BE PARTLY CLOUDY WITH
THE EXCEPTION OF ABOVE AND AROUND THUNDERSTORM ACTIVITY.
AS FOR TEMPERATURES, HIGHS WILL REMAIN ABOVE NORMAL WITH HIGHS IN
THE 100-105 RANGE FRIDAY WITH UPPER 90S EXPECTED SATURDAY THROUGH
MONDAY. TEMPERATURES COOL SLIGHTLY TUESDAY INTO WEDNESDAY BEHIND
THE AFOREMENTIONED COLD FRONT. HIGH DEWPOINTS WILL ALSO REMAIN
ACROSS THE AREA FRIDAY AND A HEAD ADVISORY MAY BE NEED TO BE
ISSUED ACROSS CENTRAL AND SOUTH CENTRAL KANSAS FRIDAY AFTERNOON AS
HEAT INDICES LOOK TO REACH ABOVE 105 DEGREES. LOWS WILL ALSO
REMAIN ABOVE NORMAL WITH OVERNIGHT TEMPERATURES RANGING FROM THE
UPPER 60S ACROSS WEST CENTRAL KANSAS TO MID 70S ACROSS SOUTH
CENTRAL KANSAS FRIDAY NIGHT THROUGH MONDAY NIGHT. LOWS THEN
DECREASE A FEW DEGREES AS WE HEAD INTO THE MID PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1210 PM CDT THU JUL 23 2015
A WARM FRONT WILL LIFT NORTH ACROSS SOUTHWEST KANSAS TODAY AND
NORTH CENTRAL KANSAS LATE TONIGHT. AS THIS SURFACE BOUNDARY PASSES
A SOUTHEAST WIND AT 10 TO NEAR 15 KNOTS WILL SHIFT TO THE SOUTH
SOUTHWEST. BUFR SOUNDINGS AND HRRR BOTH INDICATED VFR CONDITIONS
THIS AFTERNOON AND TONIGHT. AREAS OF IFR CONDITIONS FROM STRATUS
AND MVFR VISIBILITIES FROM EARLY MORNING FOG WILL BE POSSIBLE
NORTH OF THE WARM FRONT. AT THIS TIME GIVEN WHERE THIS SURFACE
BOUNDARY IS FORECAST TO BE LOCATED AROUND 12Z FRIDAY BY SEVERAL
MODELS WILL TREND TOWARDS LOWER CEILINGS AND VISIBILITIES IN THE
HYS AREA FOR SEVERAL HOURS AROUND DAYBREAK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 73 101 73 / 20 10 20 20
GCK 99 72 101 71 / 10 10 30 30
EHA 98 70 99 70 / 10 10 20 20
LBL 100 72 100 72 / 10 10 20 20
HYS 96 74 102 74 / 20 20 30 30
P28 98 76 102 76 / 50 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...HOVORKA_42
LONG TERM...HOVORKA_42
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS PADUCAH KY
844 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 844 PM CDT FRI JUL 24 2015
UPDATED THE FORECAST TO REMOVE ALL POPS THROUGH THE REMAINDER OF
THE NIGHT. CONVECTION OVER MISSOURI HAS PUSHED WELL WEST OF OUR
AREA...AND THE LATEST HRRR TAKES IT FARTHER TO THE SOUTH AND WEST
THROUGH THE NIGHT. THE NEAREST CONVECTION NORTHWEST OF THE REGION
IS OVER SOUTHERN NEBRASKA...AND ALL INDICATIONS ARE THAT WHAT EVER
IS LEFT OF IT WILL NOT REACH OUR REGION BY 12Z.
THE OTHER ADJUSTMENT WAS TO SHOW A SHARPER DEWPOINT GRADIENT TO
MATCH OBSERVATIONS. WITH WINDS EXPECTED TO BE CALM AND SKIES
EXPECTED TO REMAIN CLEAR THROUGH THE NIGHT...GOOD RADIATIONAL
COOLING SHOULD TAKE TEMPERATURES CLOSE TO THE CURRENT DEWPOINTS.
AS A RESULT...KNOCKED LOW TEMPERATURES DOWN A COUPLE OF DEGREES IN
THE EVANSVILLE TRI STATE REGION.
WITH CONDITIONS FORECAST TO BE CLOSE TO SATURATION BY
DAYBREAK...WILL HAVE TO MONITOR FOR FOG POTENTIAL...ESPECIALLY IN
THE SOUTHWEST HALF OF THE AREA WHERE BETTER LOW-LEVEL MOISTURE IS
PRESENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 319 PM CDT FRI JUL 24 2015
FIRST ITEM IS...WE WILL BE NEAR HEAT ADVISORY CRITERIA THIS
WEEKEND ACROSS THE OZARK FOOTHILL REGION OF SEMO. WILL LET THE
MID SHIFT ADDRESS THIS AS WE ARE BARELY AT CRITERIA. COORD WITH MEG
AND THEY DO NOT HAVE ONE OUT YET TO OUR SOUTH. HI RES MODELS KEEP
CONVECTION WEST OF SEMO REST OF TODAY. WILL KEEP IT DRY THROUGH
MIDNIGHT AND MONITOR. AFTER MIDNIGHT THE MODELS DEVELOP SOME
CONVECTION OVER SEMO (MAINLY LATE). HAVE SLIGHT CHANCE POPS IN TO
ACCOUNT FOR THIS.
WE HAVE HAVE A CONTINUED SLIM CHANCE OF CONVECTION FAR WEST
SATURDAY. QUASI MID LEVEL RIDGE SHOULD PRECLUDE EASTWARD
EXPANSION. HOWEVER BY SATURDAY NIGHT INTO SUNDAY...WE TRANSITION
BACK TO A NW FLOW ON THE EDGE OF H5 RIDGE TO OUR SW. CHANCES OF
CONVECTION INCREASE FROM THE NW AS A RESULT. HEIGHTS START TO RISE
SUNDAY NIGHT AND SHIFT BEST CONVECTIVE CHANCES TO OUR NE.
TEMPS WILL CONTINUE TO BE A BLEND OF PERSISTENCE AND MOS DURING
THE DAY...AND NEAR OR A DEGREE OR TWO ABOVE MOS AT NIGHT.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 319 PM CDT FRI JUL 24 2015
THE PAH FORECAST AREA WILL REMAIN ON THE FRINGES OF A SRN CONUS
MID/UPPER RIDGE FOR THE FIRST HALF OF THE EXTENDED FORECAST PERIOD.
MED RANGE MODELS (DETERMINISTIC AND ENSEMBLES) HAVE SHOWN SOME
VARIABILITY...BUT ARE IN GENERAL AGREEMENT ON THE OVERALL SYNOPTIC
PATTERN. IN THE LATTER HALF OF THE PERIOD...A ROBUST SHRTWV ALOFT IS
PROGGED TO SWEEP THROUGH THE NRN HALF OF THE CONUS...DRAGGING A SFC
BOUNDARY THROUGH OUR REGION. THIS WILL RESULT IN HOT HUMID
CONDITIONS AHEAD OF THE SYSTEM...AND SOMEWHAT COOLER AND DRIER
CONDITIONS BEHIND THE SYSTEM.
A QUASI-STATIONARY FRONTAL BOUNDARY MAY BE IN NRN REACHES OF THE PAH
FORECAST AREA ON MON/MON NIGHT. SUBTLE MID LEVEL SHRTWV ENERGY MAY
ACT ON THIS BOUNDARY AND THE AVAILABLE MOISTURE TO GENERATE SOME
SHOWERS AND TSTMS...BUT ONLY FOR PARTS OF SERN IL/SWRN IND/ERN
PENNYRILE REGION.
TUE/TUE NIGHT LOOKS DRY UNDER THE CAPPING INFLUENCE OF THE SRN
RIDGE...THEN HEIGHT FALLS SHOULD BEGIN TO HAPPEN BY WED...AND THIS
MAY BE ENOUGH TO TAP THE TROP`S MOISTURE AND INSTABILITY FOR THE
DEVELOPMENT OF WIDELY SCATTERED ACTIVITY JUST ABOUT ANYWHERE. AT
THIS TIME...FROPA IS SLATED TO OCCUR WED NIGHT. THE FORCING
ASSOCIATED WITH THIS FEATURE WILL INCREASE THE CHANCES OF PCPN FOR
THE ENTIRE REGION MAINLY EARLY THU. STILL...POPS WILL NOT BE HIGHER
THAN 40 PERCENT DURING THE ENTIRE EXTENDED FORECAST.
WITH DEWPOINTS INITIALLY IN THE LOWER HALF OF THE 70S...EXPECT A
ROUND OF UNCOMFORTABLE AFTERNOON HEAT INDICES THROUGH WED. READINGS
OF 105 (HEAT ADVISORY CRITERIA) MAY BE COMMON IN THE WRN HALF OF THE
REGION MON...AND ACROSS THE ENTIRE REGION BY TUE AND WED.
&&
.AVIATION...
ISSUED AT 1032 AM CDT FRI JUL 24 2015
VFR CONDITIONS FORECAST TODAY THROUGH EARLY TONIGHT. LATE TONIGHT
SOME MVFR FOG POSSIBLE KPAH AND KCGI...LESS LIKELY KEVV/KOWB
AREAS. WINDS LIGHT.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...DRS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
255 AM EDT THU JUL 23 2015
.UPDATE...
ISSUED AT 225 AM EDT THU JUL 23 2015
ADJUSTMENTS HAVE BEEN MADE TO HOURLY TEMPERATURE AND DEWPOINT
TRENDS BASED ON RECENT OBSERVATIONS. POPS WERE ADJUSTED UP
SLIGHTLY TOWARD DAWN IN THE SW PART OF THE CWA AHEAD OF AN
APPROACHING DISTURBANCE. OTHERWISE...NO CHANGES.
UPDATE ISSUED AT 1100 PM EDT WED JUL 22 2015
HAVE ONLY MADE VERY MINOR CHANGES ONCE AGAIN...BASED LATE EVENING
OBS/TRENDS.
UPDATE ISSUED AT 837 PM EDT WED JUL 22 2015
MADE ONLY MINOR ADJUSTMENTS TO THE FORECAST BASED ON LATEST OBS
AND 18Z MODEL RUNS...WITH LITTLE SUBSTANTIVE CHANGE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 310 PM EDT WED JUL 22 2015
18Z SFC ANALYSIS SHOWS HIGH PRESSURE BUILDING DEEPER INTO THE OHIO
VALLEY AND NORTHERN KENTUCKY. THIS HAS BROUGHT DRIER AIR TO THE
NORTHERN SECTIONS OF THE CWA WHERE SOME MID 50S ARE NOTED WHILE TO
THE SOUTH MIDDLE AND UPPER 60S ARE COMMON. THE HIGH ALSO HELPED TO
BREAK UP AND LIFT THE LOWER STRATUS DECK FROM THIS MORNING. ON
SATELLITE AND RADAR...A PAIR OF MCVS ARE MOVING EAST INTO AND
THROUGH THE TENNESSEE VALLEY. THE LEADING ONE OF THESE IS JUST
ABOUT TO PUSH SOME LIGHT SHOWERS INTO THE CUMBERLAND VALLEY NEAR
THE TENNESSEE BORDER. OTHERWISE...IT IS A PLEASANT ENOUGH DAY OUT
THERE UNDER PARTLY SUNNY DAYS WITH TEMPERATURES RANGING FROM NEAR
80 NORTH TO THE MID 80S SOUTH ALONG WITH LIGHT NORTHWEST WINDS.
THE MODELS ARE IN GOOD AGREEMENT WITH THE MAIN PATTERN ALOFT
THROUGH THE SHORT TERM PORTION OF THE FORECAST. THEY ALL AGREE
THAT FLAT FLOW CURRENTLY ABOVE KENTUCKY WILL BECOME MORE
NORTHWESTERLY WITH TIME AS RIDGING BUILDS OVER THE SOUTHERN
PLAINS INTO FRIDAY MORNING. DURING THIS TRANSITION...WEAK
SHORTWAVES WILL RIDE THROUGH KENTUCKY STARTING WITH THE MCVS
PASSING TO THE SOUTH THIS AFTERNOON AND TONIGHT. GIVEN THE SMALL
SCALE NATURE OF THESE FEATURES WILL FAVOR THE HIGHER RESOLUTION
NAM12 AND HRRR FOR WX DETAILS.
SENSIBLE WEATHER WILL FEATURE A SMALL CHANCE FOR SHOWERS OR A
STRAY THUNDERSTORM ACROSS THE SOUTHERN TIER THROUGH THE EVENING
AND INTO THE OVERNIGHT AS THE MINOR MID LEVEL WAVES PASS BY. THE
CLOUDS ASSOCIATED WITH THESE SHOULD KEEP THE FOG A BIT MORE
LIMITED THROUGH THE NIGHT AND INTO THURSDAY MORNING. THE THREAT OF
CONVECTION CONTINUES FOR MUCH OF THE SOUTHERN PARTS OF THE AREA
DURING THE DAY THURSDAY...BUT WITH LITTLE IN THE WAY OF SUPPORT
FOR ANYTHING BECOMING ORGANIZED OR TOO STRONG. THIS LEADS TO A
BETTER CHANCE FOR VALLEY FOG LATER THURSDAY NIGHT AS THE WAVES
PULL OUT OF KENTUCKY. TEMPERATURES WILL BE NEAR NORMAL OR A
LITTLE ON THE COOL SIDE THROUGH FRIDAY MORNING.
USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WINDS INTO
TONIGHT AND THEN THE SUPERBLEND THEREAFTER. DID MAKE SOME MINOR
ADJUSTMENTS TO THE LOWS TONIGHT AND THURSDAY NIGHT BASED ON
TERRAIN DIFFERENCES AND THE EXPECTATION OF RIDGE TO VALLEY
TEMPERATURE DIFFERENCES. AS FOR POPS...ENDED UP CLOSER TO THE
DRIER MET MOS THAN THE MAV TONIGHT AND THURSDAY WHILE WAS IN LINE
WITH THE LOW POP CONSENSUS FOR THURSDAY NIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 245 PM EDT WED JUL 22 2015
UPPER LEVEL RIDGE OF HIGH PRESSURE WILL BE ENTRENCHED OVER TEXAS AND
THE SOUTHERN PLAINS THROUGH THE PERIOD KEEPING NORTHWEST FLOW IN
PLACE ACROSS THE OHIO AND TENNESSEE VALLEYS. DRY HIGH PRESSURE WILL
BE IN PLACE AT THE SURFACE FRIDAY AND SATURDAY WITH A DRY AND
SEASONABLY WARM AND NOT SO HUMID FORECAST THE RESULT. A SHORTWAVE
WILL THEN TRAVERSE THE US/CANADIAN BORDER OVER THE WEEKEND
FLATTENING THE RIDGE AND SENDING A WEAK COLD FRONT SOUTHEASTWARD
TOWARD OUR REGION. THE FRONT IS EXPECTED TO REMAIN IN THE VICINITY
WHILE GRADUALLY WASHING OUT EARLY NEXT WEEK. THIS WILL KEEP A DAILY
CHANCE OF SHOWERS AND THUNDERSTORMS IN OUR FORECAST SUNDAY THROUGH
WEDNESDAY...WITH COVERAGE LIKELY PEAKING IN THE AFTERNOON AND EARLY
EVENING HOURS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 235 AM EDT THU JUL 23 2015
A PASSING MID LEVEL DISTURBANCE AND SFC WAVE OF LOW PRESSURE
PASSING SOUTH OF THE AREA WILL BRING INCREASING MOISTURE AND THE
THREAT FOR SHRA AND POSSIBLY EVEN TSRA ACROSS THE SOUTH. GENERALLY
VFR CIGS AND VIS ARE EXPECTED WITH THIS ALTHOUGH LOCATIONS SOUTH
OF THE TAF SITES NEAR THE VA AND TN BORDERS MAY EXPERIENCE SOME
VFR BETWEEN 12Z AND 0Z MAINLY IN ANY HEAVIER SHOWERS OR TSRA.
WINDS WILL BE LIGHT THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...ABE
AVIATION...JP
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1140 PM CDT WED JUL 22 2015
.UPDATE...
ISSUED AT 1140 PM CDT WED JUL 22 2015
UPDATED AVIATION SECTION FOR 06Z TAF PACKAGE.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 231 PM CDT WED JUL 22 2015
MINOR DISTURBANCE SEEN OVER SW MO HEADING EAST WITH SOME UPTICK IN
CONVECTION NOTED. HRRR HAS A REASONABLE HANDLE ON THIS ACTIVITY
THROUGH 00Z-03Z...MOVING THE ACTIVITY EAST. LIGHTNING PROGS OFF
THE REFRESH MODEL NOT IMPRESSIVE...AND AS PREVIOUSLY DISCUSSED...
MID LEVEL MARGINAL LAPSE RATES AND WEAK ML CAPES MEANS WE WILL
KEEP THUNDER MENTION AT ISOLATED. BETTER POPS WILL BE ACROSS SE MO
INTO WRN KY AND SRN TIP OF IL INITIALLY. SHOULD REMAIN DRY EARLY
TONIGHT UP ALONG THE I-64 CORRIDOR. SUPPOSE A SPRINKLE CANNOT BE
RULED OUT THERE. OVERNIGHT...THE CHANCE OF CONVECTION WILL
CONTINUE...WITH BEST POPS SRN 1/2 OF THE AREA. A SLIGHT NORTHWARD
EXPANSION IS FORECAST ESPECIALLY BY THE NAM EVEN UP TOWARD THE
KEVV TRI-STATE AS MOISTURE INCREASES THAT DIRECTION. WILL GUIDE
POPS INTO THAT AREA.
THURSDAY...BEST POPS WILL SHIFT SE WITH TIME COINCIDENT WITH THE
DEPARTURE OF MID LEVEL ENERGY AND BEST MOISTURE...AND AS THE MID
TROP FLOW VEERS MORE TO THE NW. THE VEERING WILL CONTINUE WITH
DRYING INCREASING EAST OF THE MISSISSIPPI INTO THURSDAY NIGHT. WE
DO CONTINUE WITH A CHANCE OF CONVECTION OVER SE MO WHERE MOISTURE
AND INSTABILITY ARE FORECAST TO EXIST. THAT CHANCE WILL CONTINUE
INTO AT LEAST THE FIRST 1/2 OF FRIDAY BEFORE HEADING SSE. FRIDAY
NIGHT DRY FOR NOW...BUT THIS IS NOT A GIVEN. WE COULD SEE AN
EASTWARD EXPANSION OF THE MOISTURE OUT OF MISSOURI WHICH COULD
LEAD TO SOME LATE NIGHT CONVECTION. THERE IS CONSIDERABLE MODEL
DISAGREEMENT WITH RESPECT TO THIS. WILL WAIT FOR A MORE CONSISTENT
SIGNAL.
TEMPERATURES ARE ESSENTIALLY A BLEND OF MOS. TRENDED AWAY FROM
GFS MOS WHEN IT WAS AT ITS WARMEST ESPECIALLY FRIDAY. IT HAS NOT
PERFORMED WELL AS OF LATE...ESPECIALLY DURING THE RECENT HEAT
EVENT (OPPRESSIVE EVAPOTRANSPIRATION EFFECTS/HIGH DEW POINT AIR)
IN WHICH AMBIENT TEMPS SEEMED TO REACH A LIMIT...JUST BELOW WHAT
GUIDANCE WOULD PROJECT FOR HIGHS.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 231 PM CDT WED JUL 22 2015
THOUGH THE FINER DETAILS ARE MORE DIFFICULT TO PIN DOWN...THE
GENERAL SCENARIO IN THE EXTENDED TIME FRAME WILL BE THE PAH FORECAST
AREA WILL BE ON THE PERIPHERY OF A MID/UPPER LEVEL RIDGE OVER MOST
OF THE SRN STATES. TWO MAIN NRN STREAM SHRTWVS ARE PROGGED BY THE
MED RANGE MODELS TO MOVE BY TO THE NORTH...ONE DURING THE WEEKEND...
AND ONE IN THE MIDDLE OF NEXT WEEK. EACH SHOULD ENHANCE SOMEWHAT THE
LIKELIHOOD OF SHOWER AND TSTM DEVELOPMENT ACROSS PARTS OF OUR REGION.
EARLY IN THE PERIOD...A NORTH-SOUTH FRONTAL BOUNDARY IS EXPECTED TO
BE IN PLACE IN FAR WRN SECTIONS OF THE PAH FORECAST AREA.
MEANWHILE...A LINGERING WEDGE OF RELATIVELY DRIER AIR WILL BE IN
PLACE OVER THE REST OF THE REGION. LOW LEVEL WINDS SHOULD EVENTUALLY
TURN AROUND TO THE SOUTH OVER THE WEEKEND...ENCOURAGING MORE
MOISTURE ADVECTION INTO THE AREA. WITH THIS SETUP...AFTERNOON TEMPS
AND DEWPOINTS SHOULD BE SEVERAL DEGREES HIGHER IN THE WEST VS. THE
EAST ESPECIALLY SAT. THUS...HEAT INDICES COULD SPIKE TO HEAT
ADVISORY CRITERIA IN THE WEST OVER THE WEEKEND. HEAT INDICES BETWEEN
100 AND 105 SHOULD BE MORE COMMON ACROSS THE ENTIRE REGION
AFTERWARDS.
THE MED RANGE MODELS GENERALLY DEPICT THE PRESENCE OF NRN STREAM
SHRTWV ENERGY ALOFT IN THE AREA BY EARLY SUNDAY. THE DESTABILIZING
EFFECT OF THIS FEATURE WILL COMBINE WITH THE INCREASINGLY UNSTABLE
AIRMASS TO GENERATE SCATTERED SHOWER AND TSTM ACTIVITY PRIMARILY
SUNDAY/SUNDAY NIGHT...WITH THE PENNYRILE REGION OF WRN KY HAVING THE
LEAST POP. IF A SEWD-MOVING SFC BOUNDARY MAKES IT INTO OUR AREA BY
SUNDAY NIGHT...IT MAY BECOME UNRECOGNIZABLE. THE MODEL BLEND SHOWS A
PERSISTENT SRLY COMPONENT TO THE SFC WINDS THROUGH SUNDAY NIGHT AND
BEYOND.
IT APPEARS A SIMILAR PATTERN WILL SET UP EARLY NEXT WEEK...AS
ANOTHER SFC BOUNDARY MAY SET UP IN THE FAR WEST...WITH ANOTHER
(POSSIBLY STRONGER) SEWD-MOVING SFC BOUNDARY APPROACHING. THIS
SHOULD MEAN SOMEWHAT DIMINISHED CHANCES OF SHOWERS/TSTMS POPPING UP
UNTIL WED...WHEN THE PARENT SHRTWV WILL BE CLOSER TO THE REGION.
SCATTERED ACTIVITY IS EXPECTED AGAIN BY THEN. RATHER WEAK FLOW ALOFT
WILL NOT NECESSARILY BE CONDUCIVE TO SEVERE WEATHER IN OUR REGION.
TEMPS/DEWPOINTS IN ANY ONE AREA ARE NOT EXPECTED TO CHANGE MUCH
DURING THE EXTENDED PERIOD...OUTSIDE OF TSTM ACTIVITY. LOWER TO
MIDDLE 90S WILL PREVAIL...WITH DEWPOINTS IN THE LOWER 70S FOR ALMOST
THE ENTIRE TIME...YIELDING THE AFOREMENTIONED HEAT INDICES.
&&
.AVIATION...
ISSUED AT 1140 PM CDT WED JUL 22 2015
ISOLATED SHOWERS ARE POSSIBLE AT MAINLY AT KCGI/KPAH THROUGH 13Z.
MVFR VSBYS ARE POSSIBLE MAINLY AT KCGI/KPAH BETWEEN 09Z-13Z. VFR
CIGS EXPECTED OVERALL AT ALL TAF SITES. WINDS OVERNIGHT WILL BE
LIGHT FROM THE NORTHEAST TO EAST, INCREASING TO AROUND 5 KTS AFTER
13Z.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...CN
LONG TERM...DB
AVIATION...RST
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1029 PM EDT FRI JUL 24 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 330 PM EDT FRI JUL 24 2015
AN APPROACHING WEAKENING COLD FRONT WILL CAUSE SCATTERED SHOWERS
AND THUNDERSTORMS TO DEVELOP VERY LATE TONIGHT THROUGH SATURDAY.
WIDESPREAD RAIN IS NOT ANTICIPATED AND MOST OF THIS TIME PERIOD
WILL BE DRY AND VERY WARM. HOT AND INCREASINGLY HUMID WEATHER WILL
DEVELOP SUNDAY THROUGH THE MIDDLE OF NEXT WEEK WITH INCREASING
POTENTIAL FOR SOME THUNDERSTORMS TOWARD THE MIDDLE OF NEXT WEEK.
&&
.UPDATE...
ISSUED AT 1029 PM EDT FRI JUL 24 2015
UPSTREAM TRENDS SUGGEST IT MAY TAKE UNTIL AFTER 5 OR 6 AM FOR
ANY SHOWERS TO GET IN HERE... AND THE THUNDER RISK LOOKS RATHER
LIMITED UNTIL AFTER 11 AM SATURDAY BASED ON LATEST RAP MU CAPE
PROGS. HAVE ADJUSTED POP/WX/SKY GRIDS TO ACCOUNT FOR LATEST
TRENDS AND SHORT RANGE GUIDANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 330 PM EDT FRI JUL 24 2015
PRIMARY SHORT TERM FCST CONCERNS INVOLVE ASSESSMENT OF CONVECTIVE
POTENTIAL VERY LATE TONIGHT THROUGH SATURDAY AFTERNOON.
A WEAKENING COLD FRONT WILL CAUSE SCATTERED SHOWERS AND A FEW
THUNDERSTORMS TO DEVELOP NEAR TO NW OF A LINE FROM KGRR TO KMOP
BETWEEN 06Z AND 12Z SATURDAY AS SUGGESTED BY 12Z NSSL WRF
GUIDANCE. THE STORMS WILL DEVELOP IN AN AXIS OF INCREASING
ELEVATED INSTABILITY AND WITH LOW LEVEL MOISTURE POOLING ALONG AND
AHEAD OF THE FRONT.
SEVERE WX IS NOT ANTICIPATED LATE TONIGHT DUE TO LACK OF DEEP LAYER
SHEAR... WEAK INSTABILITY AND WEAK FORCING FROM THE FRONT. SCATTERED
SHOWERS AND STORMS WILL REDEVELOP ALONG AND JUST AHEAD OF THE FRONT
SATURDAY AS INSTABILITY INCREASES WITH DAYTIME HEATING.
CANNOT ENTIRELY RULE OUT A FEW STRONG TO ISOLATED MARGINALLY SEVERE
STORMS MAINLY OVER OUR SE FCST AREA SATURDAY NEAR TO SE OF KGRR.
OVERALL THOUGH LACK OF STRONGER FORCING... RELATIVELY WEAK
INSTABILITY AND FAIRLY WEAK DEEP LAYER SHEAR ARE ALL MITIGATING
FACTORS. INSTABILITY WILL ALSO LIKELY BE LIMITED SOMEWHAT BY MORNING
CLOUDS AND SCATTERED SHOWERS AND STORMS.
FAIR WX WILL RETURN SATURDAY NIGHT THROUGH SUNDAY AS ANOTHER HIGH
PRESSURE RIDGE BUILDS IN. THERE IS JUST A SMALL CHANCE OF SHOWER
OR THUNDERSTORM LATE SUNDAY NIGHT OVER OUR SW FCST AREA BUT A
CONSENSUS OF SHORTER TO MEDIUM RANGE GUIDANCE SUGGESTS THAT MOST
IF NOT ALL PCPN SUNDAY NIGHT WILL STAY SW TO SOUTH OF OUR FCST AREA.
FOR THE REST OF THIS AFTERNOON AND EVENING DRY AND FAIR WX WILL
CONTINUE FOR THE VAST MAJORITY OF OUR AREA. HOWEVER AN ISOLATED
RAIN SHOWER OR TWO MAY DEVELOP FROM MID TO LATE AFTN THROUGH
EARLY EVE OVER OUR FAR EASTERN FCST AREA COINCIDENT WITH MAX
INSTABILITY FROM DAYTIME HEATING.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 PM EDT FRI JUL 24 2015
MODELS STILL ADVERTISING A STRONGER COLD FRONTAL PASSAGE FOR THE
MIDDLE OF NEXT WEEK. BASED ON THE STRENGTH OF THE DEEP LAYER SHEAR
AND INSTABILITY THAT WILL BE PRESENT WHEN THE FRONT COMES
THROUGH...AND ELEVATED RISK FOR SEVERE WEATHER EXISTS. BETTER THAN
40 KNOTS OF SHEAR ARE SHOWN. WILL CONTINUE TO HIGHLIGHT THIS PERIOD
FOR STORMS...MAINLY TUE NIGHT INTO WED NIGHT.
CONTINUES TO LOOK WELL ABOVE NORMAL FOR TEMPERATURES GOING INTO WED.
850 MB TEMPS CLIMB INTO THE UPPER TEENS TO LOW 20S SUPPORT AT LEAST
MID 80S FOR HIGHS. STRONG COLD AIR ADVECTION BEHIND THE FRONT
SUGGESTS A COOLER THAN NORMAL END OF THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 805 PM EDT FRI JUL 24 2015
THE FRONTAL BOUNDARY CURRENTLY OVER EASTERN MINNESOTA WILL MOVE
EAST TONIGHT AND SATURDAY... AND MAY BRING A PERIOD OF MVFR
CIGS/VSBYS BETWEEN ROUGHLY 10Z AND 18Z. THE BEST CHANCE OF ANY
MVFR CONDITIONS IS AT MKG AND GRR.
THE CHANCE/COVERAGE OF SHOWERS AND TSTMS LOOKS PRETTY LOW AND
WILL CARRY ONLY VCSH/VCTS REMARKS WITH THE FRONTAL PASSAGE.
BELIEVE THE BEST THREAT OF ANY THUNDER IS SATURDAY
AFTERNOON/EARLY EVENING SOUTH AND EAST OF GRR.
SOUTHWEST WINDS UNDER 10 KTS TONIGHT WILL VEER WEST AND INCREASE
TO 10-15 KNOTS SATURDAY MORNING THEN BECOME NORTHWEST LATE
SATURDAY BEHIND THE FRONT.
&&
.MARINE...
ISSUED AT 330 PM EDT FRI JUL 24 2015
WINDS AND WAVE HEIGHTS WILL BRIEFLY INCREASE LATE TONIGHT WITH
WAVE HEIGHTS POTENTIALLY REACHING 2 TO 4 FEET. HOWEVER CONDITIONS
SHOULD REMAIN BELOW SMALL CRAFT/BEACH HAZARDS CRITERIA. WAVE
HEIGHTS AND WIND SPEEDS THROUGH THE WEEKEND WILL BE LIGHT WITH
WAVE HEIGHTS MAINLY AOB 2 FT.
&&
.HYDROLOGY...
ISSUED AT 1156 AM EDT FRI JUL 24 2015
RIVER LEVELS ARE FALLING AND ARE WELL BELOW BANKFULL. WITH UNDER
AN INCH OF PRECIPITATION EXPECTED THROUGH THE WEEK... THESE
CONDITIONS SHOULD CONTINUE. LOCALLY HEAVY RAINFALL COULD LEAD TO
PONDING OF WATER... MAINLY SATURDAY OR WEDNESDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...MJS
AVIATION...MEADE
HYDROLOGY...63
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
747 PM EDT FRI JUL 24 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 419 PM EDT FRI JUL 24 2015
WV IMAGERY RAP ANALYSIS INDICATED ZONAL FLOW FROM THE PAC NW TO THE
GREAT LAKES ATOP A RIDGE OVER THE SRN AND CNTRL PLAINS. THE INITIAL
SHORTWAVE OR REMNANTS OF THE MCV FROM EARLIER TODAY THAT BROUGHT AN
AREA OF CLOUDS AND VERY LIGHT SHOWERS THROUGH UPPER MI HAS LIMITED
SFC HEATING AND KEPT MLCAPE VALUES AOB 500 J/KG. CLEARING WITH
SUBSIDENCE IN THE WAKE OF THIS FEATURE HAS ALLOWED TEMPS TO CLIMB
INTO THE LOWER 80S OVER THE WEST WITH MLCAPE VALUES INTO THE 500-
1000 J/KG RANGE OVER THE FAR WEST. A SHRTWV OVER NRN MN ALONG WITH A
COLD FRONT INTO NE MN SUPPORTED SCT SHRA WITH MORE EXTENSIVE CLOUD
COVER.
EXPECT THAT THERE STILL WILL BE ENOUGH HEATING LATE THIS AFTERNOON
OVER MUCH OF WRN UPPER MI TO BOOST MLCAPE VALUES TO AROUND 1K J/KG.
WITH THE COLD FRONT AND SHRTWV EDGING INTO UPPER MI DURING PEAK
HEATING...EXPECT SCT TSRA TO DEVELOP BTWN 21Z-00Z. 0-6KM SHEAR
VALUES IN THE 30-40 KNOT RANGE WOULD BE FAVORABLE FOR STORM
ORGANIZATION WITH THE POTENTIAL FOR ISOLD SEVERE STORMS. HOWEVER...IF
THE THICKER CLOUD COVER SPREADS BACK INTO THE AREA BEFORE THE FRONT
AND STRONGER FORCING WITH THE SHRTWV ARRIVES...TSRA COVERAGE AND
STRENGTH WILL BE SUPPRESSED. ANY REMAINING SHRA/TSRA SHOULD EXIT THE
CWA AFTER 06Z WITH CLEARING MOVING IN OVERNIGHT.
SATURDAY...HIGH PRESSURE WILL BUILD INTO THE AREA WITH MOSTLY SUNNY
SKIES EXPECTED. SUNSHINE AND MIXING WITH 850 MB TEMPS AROUND 16C
SUPPORT MAX READINGS IN THE LOW TO MID 80S INLAND AND FOR LOCATIONS
FAVORED BY NW DOWNSLOPE FLOW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 321 PM EDT FRI JUL 24 2015
NAM SHOWS A SHORTWAVE TOPPING A 500 MB RIDGE OVER THE SOUTHERN U.S.
WITH A TROUGH IN THE WESTERN U.S. AND A SHORTWAVE IN THE DAKOTAS 00Z
SUN. THIS SHORTWAVE MOVES EAST ON SUN AND HAS A SHORTWAVE RIDGE
MOVING IN FOR MON. WILL HAVE IT DRY INTO THE FORECAST INTO MONDAY
BEFORE LAKE BREEZE CONVERGENCE COULD KICK SOMETHING OFF MONDAY
AFTERNOON OVER THE WEST AND CENTRAL. OVERALL...DID NOT MAKE TOO MANY
CHANGES TO THE GOING FORECAST.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB TROUGH OVER THE
ROCKIES 12Z TUE WITH A RIDGE ACROSS THE EASTERN HALF OF THE U.S. THE
TROUGH MOVES INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES ON WED
WITH A SFC COLD FRONT MOVING THROUGH THE AREA. THE UPPER TROUGH AXIS
IS OVER THE UPPER GREAT LAKES 12Z THU WITH UPPER TROUGHING REMAINING
INTO FRI. THIS WILL BRING A COOLING TREND IN THE TEMPERATURES
STARTING OUT ABOVE NORMAL ON TUE COOLING TO BELOW NORMAL ON THU AND
FRI. WITH THE TROUGHING REMAINING OVER THE AREA...HARD TO RULE OUT
PCPN AND HAVE CHANCE POPS IN THROUGH WED AND THEN SLIGHT CHANCE POPS
ON THU AND FRI WITH INSTABILITY SHOWERS AROUND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 746 PM EDT FRI JUL 24 2015
AS A COLD FRONT AND WEAK DISTRUBANCE MOVES INTO UPPER MICHIGAN LATE
THIS AFTERNOON AND EVENING...ISOLD/SCT SHRA/TSRA AE EXPECTED TO
DEVELOP AND SPREAD FROM WEST TO EAST. ALREADY SEEING SIGNS OF THIS
IN THE VCNTY OF KIWD. CONTINUE TO CARRY VCTS AT ALL TAF SITES...BUT
WILL UPDATE IF TSRA SEEM MORE CERTAIN. AS THE COLD FRONT WORKS
THROUGH OVERNIGHT THERE MAY BE BRIEF PERIOD OF MVFR CIGS BUT EXPECT
THESE TO SCATTER OUT LATE TONIGHT WITH VFR CONDITIONS AT ALL TAF
SITES FOR SATURDAY. W-NW WINDS MAY BECOME GUSTY OVER 20 KTS AT KCMX
BY AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 PM EDT FRI JUL 24 2015
AS A COLD FRONT MOVES EAST ACROSS THE LAKE LATE TONIGHT...WINDS WILL
SHIFT WRLY 15-20KTS FOR SATURDAY. HIGH PRESSURE WILL BUILD BACK INTO
THE WESTERN GREAT LAKES SAT NIGHT AND PERSIST INTO TUE KEEPING WINDS
GENERALLY BELOW 15KTS. ANY FOG OVER LAKE IS EXPECTED TO DIMINISH
SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...JLA
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
937 PM CDT FRI JUL 24 2015
.UPDATE:
ISSUED AT 934 PM CDT FRI JUL 24 2015
WEATHER LOOKS PRETTY TRANQUIL FOR THE REMAINDER OF THE EVENING AND
INTO THE FIRST PART OF THE OVERNIGHT PERIOD. THE CLUSTER OF STORMS
WHICH REGENERATED OVER CENTRAL MO EARLY THIS EVENING HAS REMAINED
WELL TO THE WEST, TRACKING SOUTH/SOUTHWEST ALONG THE INSTABILITY
GRADIENT AND LARGELY STEERED BY NORTHERLY CLOUD LAYER FLOW. THE THREAT
OF ADDITIONAL STORMS OVERNIGHT SHOULD BE PRIMARLY AFTER 200-300
AM. THE COMBINATION OF SUBTLE WEAK MID LEVEL DISTURBANCES TRACKING
ALONG THE PERIPHERY OF THE HIGH ALOFT ALONG WITH WEAK LOW-LEVEL
WAA AND MOISTURE CONVERGENCE, SUPPORT A THREAT OF POTENTIALLY
MAINTAINING A FEW OF THE STORMS ACROSS SOUTHEAST IA/NW MO, BUT
MORE LIKELY NEW STORM DEVELOPMENT ACROSS NORTHEAST MO INTO CENTRAL
MO.
GLASS
&&
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 356 PM CDT FRI JUL 24 2015
MCS WILL CONTINUE TO WORK SOUTHWARD ALONG THE CAPE GRADIENT DURING
THE NEXT FEW HOURS. THIS IS ALSO IN THE SAME DIRECTION AS THE
FORWARD PROPAGATING CORFIDI VECTORS. THERE REMAINS THE POTENTIAL
FOR SOME SEVERE WIND GUSTS WITH THIS SYSTEM AS THE RAP FORECAST
SOUNDINGS AHEAD OF IT AT KCOU ARE SHOWING INVERTED-V PROFILES. THE
LATEST OBJECTIVE ANALYSIS WHICH SHOWS MLCAPES BETWEEN 3000-4000 J/KG
AND 0-6KM SHEAR NEAR 40KTS. HAVE INCREASE POPS EARLY THIS EVENING
OVER THE EASTERN OZARKS AS THIS SYSTEM MOVES SOUTHWARD ACROSS
EASTERN MISSOURI. HAVE ALSO KEPT CHANCES OVER NORTHEAST AND CENTRAL
MISSOURI INTO WEST CENTRAL ILLINOIS LATE THIS EVENING INTO THE
OVERNIGHT HOURS AS BOTH THE NAM AND GFS ARE SHOWING A SHORTWAVE
TROUGH MOVING EAST SOUTHEAST INTO THE AREA WHICH SHOULD PROVIDE SOME
ASCENT, AND THE RAP IS SHOWING AND INCREASE IN LOW LEVEL MOISTURE
CONVERGENCE OVER THE NORTHERN HALF OF THE CWA. GOING TEMPERATURES
LOOK GOOD FOR LOWS.
BRITT
.LONG TERM: (SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 356 PM CDT FRI JUL 24 2015
THUNDERSTORM TRENDS REMAIN THE KEY QUESTION FOR THE WEEKEND. HAVE
BASICALLY ONLY TWEAKED THE MIDNIGHT SHIFT`S POPS FOR THE WEEKEND.
THIS BREAKS DOWN TO 30-50% CHANCES FOR THE ENTIRE AREA SATURDAY
THROUGH SUNDAY. HIGHER DEWPOINT TEMPERATURES OVER WESTERN AND
CENTRAL MISSOURI SHOULD OVERSPREAD MUCH OF THE AREA PUSHING CAPE
VALUES OVER 3000 J/KG. LINGERING BOUNDARY IN THE VICINITY OF THE
MISSISSIPPI RIVER SHOULD PROVIDE ENOUGH FOCUS FOR AFTERNOON
CONVECTION TO FIRE THOUGH COVERAGE IS UNCERTAIN DUE TO A DECENT CAP.
NOT OVERLY IMPRESSED WITH THE DEEP LAYER SHEAR, BUT WITH THE HIGH
INSTABILITY THERE IS CERTAINLY ENOUGH TO BE CONCERNED WITH MULTI-
CELL CLUSTERS CAPABLE OF PRODUCING STRONG WINDS.
TEMPERATURES ON SATURDAY ARE UNCERTAIN DUE TO THE CHANCES FOR
CONVECTION. HOWEVER, IT DOES APPEAR THAT WE`LL GET WARM ENOUGH TO
REACH HEAT ADVISORY CRITERIA OVER PARTS OF CENTRAL AND SOUTHEAST
MISSOURI WHERE THUNDERSTORM COVERAGE LOOKS TO BE MORE WIDELY
SCATTERED TO ISOLATED. WILL GO AHEAD AND ISSUE AN ADVISORY FOR
THESE AREAS FOR SATURDAY FOR HEAT INDEX VALUES AROUND 105. ADVISORY
MAY NEED TO BE EXPANDED IF STORMS DO NOT DEVELOP AS EXPECTED...OR
POSSIBLY DROPPED IF THE THUNDERSTORM COVERAGE IS GREATER THAN
EXPECTED.
ANOTHER SHORTWAVE IS FORECAST TO MOVE OVERHEAD SATURDAY NIGHT
ASSOCIATED WITH A MODEST LOW LEVEL JET WILL CONTINUE THE THREAT FOR
STORMS OVER MUCH OF THE AREA SUNDAY LOOKS TO BE A REPEAT OF OF
SATURDAY WITH THE SYNOPTIC BOUNDARY CONTINUING TO BE REINFORCED BY
THUNDERSTORMS. THUNDERSTORM CHANCES SHOULD BE WANING QUICKLY THOUGH
FOR SUNDAY NIGHT INTO THE BEGINNING OF NEXT WEEK AS A STRONG UPPER
LEVEL RIDGE BUILDS ACROSS THE AREA. THINK THE VAST MAJORITY OF THE
AREA SHOULD BE DRY BY LATE SUNDAY NIGHT AND MONDAY WITH ONLY SLIGHT
CHANCE POPS MONDAY AND TUESDAY. MEDIUM RANGE MODELS HAVE A WEAK COLD
FRONT MOVING THROUGH THE AREA WEDNESDAY NIGHT INTO THURSDAY WITH
ANOTHER CHANCE FOR STORMS.
CARNEY
&&
.AVIATION: (FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 610 PM CDT FRI JUL 24 2015
MAIN QUESTION OVERNIGHT WILL BE DEVELOPMENT OF FG. CURRENT TRENDS
SHOW BEST CHANCES OF DEVELOPMENT WILL BE AT COU/SUS/CPS WHERE
WINDS WILL BE LIGHTER. ATTM, THREAT LOOKS MINIMAL BUT TRENDS WILL
BE MONITORED. OTHERWISE, THREAT FOCUS TURNS TO CHANCES FOR TSRA
LATE TONIGHT INTO SAT MORNING. MDLS CONTINUE TO SHOW A THREAT FOR
UIN AROUND SUNRISE, WHICH MAY THEN DEVELOP SWD IMPACTING SUS/CPS
AND PERHAPS COU LATE IN THE MORNING AND INTO THE AFTN HRS.
HOWEVER, CONFIDENCE IN THIS SOLN IS TOO LOW TO ADD TO TAFS ATTM.
SPECIFICS FOR KSTL: HAVE KEPT TAF VFR AND DRY THRU THE PERIOD FOR
NOW. TSRA MAY DEVELOP INTO THE REGION LATE SAT MORNING INTO THE
AFTN HRS. HOWEVER, CONFIDENCE IN THIS SOLN IS TOO LOW ATTM.
TILLY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY FROM NOON TO 7 PM CDT SATURDAY FOR BOONE MO-
CALLAWAY MO-COLE MO-CRAWFORD MO-FRANKLIN MO-GASCONADE MO-
IRON MO-MONITEAU MO-MONTGOMERY MO-OSAGE MO-REYNOLDS MO-
WARREN MO-WASHINGTON MO.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
632 PM CDT FRI JUL 24 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 356 PM CDT FRI JUL 24 2015
MCS WILL CONTINUE TO WORK SOUTHWARD ALONG THE CAPE GRADIENT DURING
THE NEXT FEW HOURS. THIS IS ALSO IN THE SAME DIRECTION AS THE
FORWARD PROPAGATING CORFIDI VECTORS. THERE REMAINS THE POTENTIAL
FOR SOME SEVERE WIND GUSTS WITH THIS SYSTEM AS THE RAP FORECAST
SOUNDINGS AHEAD OF IT AT KCOU ARE SHOWING INVERTED-V PROFILES. THE
LATEST OBJECTIVE ANALYSIS WHICH SHOWS MLCAPES BETWEEN 3000-4000 J/KG
AND 0-6KM SHEAR NEAR 40KTS. HAVE INCREASE POPS EARLY THIS EVENING
OVER THE EASTERN OZARKS AS THIS SYSTEM MOVES SOUTHWARD ACROSS
EASTERN MISSOURI. HAVE ALSO KEPT CHANCES OVER NORTHEAST AND CENTRAL
MISSOURI INTO WEST CENTRAL ILLINOIS LATE THIS EVENING INTO THE
OVERNIGHT HOURS AS BOTH THE NAM AND GFS ARE SHOWING A SHORTWAVE
TROUGH MOVING EAST SOUTHEAST INTO THE AREA WHICH SHOULD PROVIDE SOME
ASCENT, AND THE RAP IS SHOWING AND INCREASE IN LOW LEVEL MOISTURE
CONVERGENCE OVER THE NORTHERN HALF OF THE CWA. GOING TEMPERATURES
LOOK GOOD FOR LOWS.
BRITT
.LONG TERM: (SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 356 PM CDT FRI JUL 24 2015
THUNDERSTORM TRENDS REMAIN THE KEY QUESTION FOR THE WEEKEND. HAVE
BASICALLY ONLY TWEAKED THE MIDNIGHT SHIFT`S POPS FOR THE WEEKEND.
THIS BREAKS DOWN TO 30-50% CHANCES FOR THE ENTIRE AREA SATURDAY
THROUGH SUNDAY. HIGHER DEWPOINT TEMPERATURES OVER WESTERN AND
CENTRAL MISSOURI SHOULD OVERSPREAD MUCH OF THE AREA PUSHING CAPE
VALUES OVER 3000 J/KG. LINGERING BOUNDARY IN THE VICINITY OF THE
MISSISSIPPI RIVER SHOULD PROVIDE ENOUGH FOCUS FOR AFTERNOON
CONVECTION TO FIRE THOUGH COVERAGE IS UNCERTAIN DUE TO A DECENT CAP.
NOT OVERLY IMPRESSED WITH THE DEEP LAYER SHEAR, BUT WITH THE HIGH
INSTABILITY THERE IS CERTAINLY ENOUGH TO BE CONCERNED WITH MULTI-
CELL CLUSTERS CAPABLE OF PRODUCING STRONG WINDS.
TEMPERATURES ON SATURDAY ARE UNCERTAIN DUE TO THE CHANCES FOR
CONVECTION. HOWEVER, IT DOES APPEAR THAT WE`LL GET WARM ENOUGH TO
REACH HEAT ADVISORY CRITERIA OVER PARTS OF CENTRAL AND SOUTHEAST
MISSOURI WHERE THUNDERSTORM COVERAGE LOOKS TO BE MORE WIDELY
SCATTERED TO ISOLATED. WILL GO AHEAD AND ISSUE AN ADVISORY FOR
THESE AREAS FOR SATURDAY FOR HEAT INDEX VALUES AROUND 105. ADVISORY
MAY NEED TO BE EXPANDED IF STORMS DO NOT DEVELOP AS EXPECTED...OR
POSSIBLY DROPPED IF THE THUNDERSTORM COVERAGE IS GREATER THAN
EXPECTED.
ANOTHER SHORTWAVE IS FORECAST TO MOVE OVERHEAD SATURDAY NIGHT
ASSOCIATED WITH A MODEST LOW LEVEL JET WILL CONTINUE THE THREAT FOR
STORMS OVER MUCH OF THE AREA SUNDAY LOOKS TO BE A REPEAT OF OF
SATURDAY WITH THE SYNOPTIC BOUNDARY CONTINUING TO BE REINFORCED BY
THUNDERSTORMS. THUNDERSTORM CHANCES SHOULD BE WANING QUICKLY THOUGH
FOR SUNDAY NIGHT INTO THE BEGINNING OF NEXT WEEK AS A STRONG UPPER
LEVEL RIDGE BUILDS ACROSS THE AREA. THINK THE VAST MAJORITY OF THE
AREA SHOULD BE DRY BY LATE SUNDAY NIGHT AND MONDAY WITH ONLY SLIGHT
CHANCE POPS MONDAY AND TUESDAY. MEDIUM RANGE MODELS HAVE A WEAK COLD
FRONT MOVING THROUGH THE AREA WEDNESDAY NIGHT INTO THURSDAY WITH
ANOTHER CHANCE FOR STORMS.
CARNEY
&&
.AVIATION: (FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 610 PM CDT FRI JUL 24 2015
MAIN QUESTION OVERNIGHT WILL BE DEVELOPMENT OF FG. CURRENT TRENDS
SHOW BEST CHANCES OF DEVELOPMENT WILL BE AT COU/SUS/CPS WHERE
WINDS WILL BE LIGHTER. ATTM, THREAT LOOKS MINIMAL BUT TRENDS WILL
BE MONITORED. OTHERWISE, THREAT FOCUS TURNS TO CHANCES FOR TSRA
LATE TONIGHT INTO SAT MORNING. MDLS CONTINUE TO SHOW A THREAT FOR
UIN AROUND SUNRISE, WHICH MAY THEN DEVELOP SWD IMPACTING SUS/CPS
AND PERHAPS COU LATE IN THE MORNING AND INTO THE AFTN HRS.
HOWEVER, CONFIDENCE IN THIS SOLN IS TOO LOW TO ADD TO TAFS ATTM.
SPECIFICS FOR KSTL: HAVE KEPT TAF VFR AND DRY THRU THE PERIOD FOR
NOW. TSRA MAY DEVELOP INTO THE REGION LATE SAT MORNING INTO THE
AFTN HRS. HOWEVER, CONFIDENCE IN THIS SOLN IS TOO LOW ATTM.
TILLY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY FROM NOON TO 7 PM CDT SATURDAY FOR BOONE MO-
CALLAWAY MO-COLE MO-CRAWFORD MO-FRANKLIN MO-GASCONADE MO-
IRON MO-MONITEAU MO-MONTGOMERY MO-OSAGE MO-REYNOLDS MO-
WARREN MO-WASHINGTON MO.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
400 PM CDT THU JUL 23 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 354 PM CDT THU JUL 23 2015
THERE STILL MAY BE AN ISOLATED SHOWER OR THUNDERSTORM EARLY THIS
EVENING OVER THE FAR SOUTHERN PART OF THE CWA EARLY THIS EVENING
WHERE THERE ARE CURRENTLY A FEW STORMS DEVELOPING IN CLOSE TO THE
STATIONARY FRONT WITH MLCAPES NEAR 1000 J/KG. ONCE WE GET PAST
DAYTIME HEATING, THINK IT WILL BE A DRY NIGHT AS A SHORTWAVE RIDGE
AXIS MOVES IN FROM KANSAS SUPPLYING SOME SUBSIDENCE. LATEST RUNS OF
THE WRF AND RAP AREA NOT SHOWING MUCH IN THE WAY OF LOW LEVEL
FORCING OR INSTABILITY THAT WOULD SUPPORT ADDITIONAL THUNDERSTORM
DEVELOPMENT FROM MID EVENING ONWARD. MOS TEMPERATURES LOOK GOOD FOR
THE LOW TEMPERATURES.
BRITT
.LONG TERM: (FRIDAY THROUGH NEXT THURSDAY)
ISSUED AT 354 PM CDT THU JUL 23 2015
PINNING DOWN THUNDERSTORM THREAT...AND INCREASING HEAT AND HUMIDITY...
ARE THE PRIMARY FORECAST CONCERNS HEADING INTO THE WEEKEND AND
THE START OF NEXT WEEK.
UPPER LEVEL RIDGE IS FORECAST TO INTENSIFY A BIT ACROSS THE REGION
DURING THE DAY ON FRIDAY, WITH REMANTS OF WEAK LOW LEVEL BOUNDARY
EXPECTED TO REMAIN LOCKED BENEATH THE INCREASING HIGH PRESSURE
ALOFT. SCENARIO ISN`T ONE THAT FAVORS A LOT IN THE WAY OF
CONVECTION, BUT WILL MAINTAIN SOME LOW POPS OVER THE OZARKS DURING
THE AFTERNOON HOURS WHERE LOW LEVEL CONVERGENCE/OROGRAPHIC LIFT
COULD BE JUST ENOUGH TO KICK OFF A FEW ISOLATED CELLS.
CONCERN FOR CONVECTION INCREASES HEADING INTO THE WEEKEND;
FIRST AS SEVERAL WEAK DISTURBANCES BEGIN TO MIGRATE OVER THE
TOP OF THE RIDGE AND INTO THE GREAT LAKES. THIS SUGGESTS A RING
OF FIRE PATTERN FROM THE NORTHERN PLAINS INTO THE MID AND UPPER
MISSISSIPPI VALLEY, AND PRIMARY QUESTION IS HOW FAR SOUTH THIS
CONVECTION WILL GET INTO OUR FORECAST AREA.
FIRST RIPPLE IN THE FLOW AND ASSOCIATED WAA IS PROGGED TO COMMENCE
LATE FRIDAY NIGHT, AND ALL MODELS BEGIN TO HINT AT SOME PRECIP IN
OUR AREA BY 12Z SATURDAY, ALTHOUGH NAM AND ECMWF ARE MUCH FURTHER
SOUTH THAN THE GFS QPF. NAM AND ECMWF CONTINUE CONVECTION ACROSS
MUCH OF THE AREA DURING THE DAY ON SATURDAY WITH SEVERAL MORE
ROUNDS SATURDAY NIGHT AND SUNDAY, WHILE GFS IS SLOWER WITH PRECIP
PUSHING INTO OUR AREA, AND FOCUSES IT SOUTHWARD SURGE OF QPF IN
THE SATURDAY NIGHT/SUNDAY TIME FRAME.
OBVIOUSLY...THERE IS CONSIDERABLE UNCERTAINTY IN SPECIFIC POP
TRENDS OVER THE WEEKEND, WITH A MYRIAD OF ILL-DEFINED FEATURES
(EXTREMELY WEAK UPPER LEVEL DYNAMICS, SEVERAL BOUTS OF WEAK
NOCTURNAL JET FORCING, AN INCREASINGLY MOIST AND UNSTABLE AIRMASS,
OUTFLOW BOUNDARIES, AND WHAT APPEARS TO BE WEAK SYNOPTIC FRONT TO
OUR NORTH THAT WILL BE BEAT SOUTH BY SEVERAL CONVECTIVE COMPLEXES)
THAT COULD PRODUCE QUITE A BIT OF ACTIVE WEATHER ACROSS THE FA. AS
NOTED BY WFO EAX EARLIER TODAY...THIS UPCOMING PATTERN IS VERY
SIMILAR TO THAT THE CENTRAL CONUS EXPERIENCED ABOUT A WEEK AGO.
GIVEN THIS UNCERTAINTY...HAVE PRETTY MUCH MAINTAINED GOING FORECAST
TRENDS WHICH INDICATE THUNDERSTORM CHANCES RAMPING UP INTO THE
CHANCE CATEGORY OVER MUCH OF THE AREA LATE FRIDAY NIGHT AND
SATURDAY. IN TRUTH, THERE WILL PROBABLY BE PERIODS OF MUCH HIGHER
AND MUCH LOWER POPS, BUT THOSE ADJUSTMENTS WILL HAVE TO BE MADE
WHEN SHORT-TERM TRENDS BECOME A BIT MORE CLEAR.
OTHER CONCERN IS INCREASING LEVELS OF HEAT AND HUMIDITY AS GRADUAL
INCREASE IN SOUTHERLY LOW LEVEL FLOW ALLOWS DEWPOINTS TO REBOUND
INTO THE MIDDLE AND UPPER 70S. ALTHOUGH THIS INCREASE WILL BE FELT
WEST OF THE MISSISSIPPI RIVER TOMORROW, PRIMARY CONCERN WILL BE IN
THE SATURDAY-SUNDAY TIME FRAME WHEN AFTERNOON DEWPOINTS ARE
EXPECTED TO BE IN THE MID TO UPPER 70S AND TEMPERATURES SHOULD BE
WELL IN THE 90S. TEMPERATURES WILL BE THE KEY TO HOW OPPRESSIVE IT
WILL BECOME, AND THIS WILL BE TIED TO AMOUNT OF CONVECTION AND
CLOUDINESS THE AREA EXPERIENCES. IF CLOUDS AND CONVECTION ARE AT A
MINIMUM, HEAT INDICIES OF 105 WILL BE LIKELY OVER PARTS OF MID
MISSOURI. AGAIN, CONSIDERABLE UNCERTAINTY AT THIS POINT WITH THE
ABOVE PARAMETERS, SO WILL LET MID SHIFT TAKE ANOTHER LOOK BEFORE
HOISTING ANY HEADLINES.
SEASONABLY WARM TEMPS...ALONG WITH LOW THUNDERSTORM CHANCES...
REMAIN IN THE FORECAST THROUGH WEDNESDAY AS SOME REMNANTS OF LOW
LEVEL BOUNDARY AND UNSTABLE AIRMASS REMAINS LOCKED OVER THE
REGION. POPS SHOULD BE A BIT HIGHER BY MIDWEEK AS SHORTWAVE BREAKS
DOWN THE UPPER LEVEL RIDGE AND ALLOWS A FRONTAL BOUNDARY TO PUSH
INTO THE AREA.
TRUETT
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1226 PM CDT THU JUL 23 2015
EXPECT MAINLY DRY AND VFR CONDITIONS THROUGH THE PERIOD. ONLY
EXCEPTION IS THERE MAY BE SOME PATCHY MVFR FOG IN LOW LYING AREAS
INCLUDING KSUS AND KCPS LATE TONIGHT, HOWEVER UNCERTAINTY IS TOO
HIGH AT THIS POINT TO INCLUDE IN THE TAFS. WINDS WILL REMAINS
LIGHT EAST TO SOUTHEASTERLY.
SPECIFICS FOR KSTL: EXPECT DRY AND VFR CONDITIONS THROUGH THE
PERIOD.
BRITT
&&
.PRELIMINARY POINT TEMPS/POPS:
SAINT LOUIS 72 90 74 93 / 5 5 10 40
QUINCY 66 87 72 89 / 5 5 40 40
COLUMBIA 70 90 74 93 / 10 20 10 30
JEFFERSON CITY 71 91 76 93 / 10 20 10 30
SALEM 65 87 69 89 / 5 5 10 20
FARMINGTON 67 87 69 88 / 10 10 10 20
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1236 AM CDT Thu Jul 23 2015
.MESOSCALE DISCUSSION...
Issued at 1042 PM CDT WED JUL 22 2015
There appears to be a growing number of signals for localized
heavy rainfall/flooding potential from late tonight into
Thursday morning. A surface frontal boundary will remain draped
across southern Missouri and will move very little through at
least early Thursday morning. Meanwhile, a developing low level
jet stream will induce increased isentropic upglide overnight from
part of eastern Kansas across southwestern Missouri into northern
Arkansas. This is also in line with a slug of stronger 850 mb
theta-e advection and moisture transport. This should result in
scattered to possibly numerous showers and thunderstorms developing
as we get into later tonight and early Thursday morning.
What is somewhat concerning is the high moisture content of the
atmosphere. The 00Z KSGF sounding indicated about 2.00" of
precipitable water content. This along with high freezing levels
will result in very efficient rainfall rates. Additionally,
there appears to be potential for training bands of convection as
mean wind fields are fairly aligned with a low level theta-e and
overall CAPE gradient. Recent trends in models such as the 00Z NAM
and GFS as well as recent HRRR runs seem to back the potential for
locally heavy rainfall. We updated the Hazardous Weather Outlook
to cover these concerns a bit earlier this evening.
One other final note was the addition of fog to the forecast.
While we are not looking at widespread dense fog, any areas that
experience appreciable breaks in cloud cover should see at least
patchy fog. This will especially be true along and north of that
front.
&&
.SHORT TERM...(This Evening through Thursday)
Issued at 328 PM CDT WED JUL 22 2015
Scattered showers and few storms will continue to occur mainly
south of Highway 60 into this evening as weak upper level
disturbance tracks east across Kansas and a front remains stalled
near the Missouri Arkansas border. Instability has increased
across southern Missouri with the heating of the day, but with
weak deep layer shear and not very steep low level steep rates the
will keep the severe risk very low with this activity. These
storms will weaken with the loss of day time heating later this
evening.
Tonight another upper level shortwave will move out of the central
Plains and across the region and could generate additional
scattered showers and storms overnight. Deep layer shear will
increase with the shortwave, but with the loss of day time
heating and being north of the stalled front instability will be
limited and not expected much in the way of severe weather
overnight. Thursday looks mainly dry as the area will be behind the
upper level disturbance. The front will begin to lift to the north
on Thursday resulting in temperatures ranging from the middle 80s
across central Missouri to around the 90 degree mark across
southeastern Kansas Thursday afternoon.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 328 PM CDT WED JUL 22 2015
The warm front will continue to lift northeast through the region
Thursday night into early Friday. Scattered storms will be
possible along and north of the front Thursday night, mainly
across the eastern Ozarks.
An upper level ridge will begin to slide east into the area on
Friday and then over the area on Saturday. Highs in the lower to
middle 90s are expected west of Highway 65 on Friday afternoon and
then across the entire area on Saturday. Heat Index values of 100
to 108 are expected Friday and Saturday afternoons.
An upper level disturbance will push the ridge back slightly to
the west Saturday night and Sunday. Shower and thunderstorms will
be possible across the eastern Ozarks as a result but the better
chances should remain north and east of the area as the ridge does
not appear to retreat to far to the west.
The ridge will build right back over the region next Monday and
Tuesday with highs in the lower to middle 90s occurring each
afternoon.
Medium range models indicate the ridge will flatten allow a front
to approach from the north during the middle of next week, bringing
chances for showers and thunderstorms to the region.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1222 AM CDT THU JUL 23 2015
Scattered showers and thunderstorms will develop near a frontal
boundary across southern Missouri through Thursday morning. MVFR
and local IFR conditions can be expected with this activity.
Additionally, patchy areas of IFR fog will also develop. LIFR
visibilities will continue at times around KBBG. Conditions will
then improve by Thursday afternoon with VFR conditions then
expected into Thursday evening. Winds will remain light through
the period.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
MESOSCALE...Schaumann
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS HASTINGS NE
438 AM CDT THU JUL 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CDT THU JUL 23 2015
ALOFT: THE PATTERN THAT HAS BEEN IN PLACE SINCE THE BEGINNING OF
THE MONTH REMAINS LOCKED IN. SUBTROPICAL HIGH PRES WAS OVER TX
WITH TROFS OVER THE ERN AND WRN USA. THERE WILL BE NO CHANGE THRU
TONIGHT. SYNOPTIC FORCING WILL BE NIL.
SURFACE: HIGH PRES WAS OVER THE MIDWEST AND OH VALLEY AND WILL
REMAIN PARKED THERE THRU TONIGHT. LOW PRES WAS ADVANCING THRU
CNTRL CANADA THIS MORNING. ITS COOL FRONT EXTENDED SW INTO THE NRN
ROCKIES...BISECTING MT/ID. THIS FRONT WILL MOVE INTO THE NRN
PLAINS TODAY...WITH ITS TAIL END ENTERING NRN/WRN NEB TONIGHT.
A WEAK/SUBTLE SHORTWAVE TROF /BEST SEEN AT 700 MB/ APPEARS TO BE
RESPONSIBLE FOR THE FEW SHWRS/TSTMS THAT HAVE BEEN ON-GOING THRU
THE NIGHT ALONG THE SD/NEB BORDER. AN ISOLATED CELL OR TWO HAS
TRIED TO DEVELOP AT TIMES N-NW OF ODX. VARIOUS MODELS AND THE HI-
RES RAP ENSEMBLE SUGGEST THESE SHWRS/TSTMS COULD INCREASE IN
COVERAGE AND BUILD DOWN INTO AREAS E OF HWY 281.
IR SATELLITE DOES SHOW A N-S ORIENTED BAND OF CLOUDS HAS DEVELOPED
AND BVN/AUH/JYR ALL NOW HAVE CIGS AROUND 6-7K FT.
TODAY: COULD SEE AN ISOLATED SHWR/TSTM EARLY N AND E OF THE TRI-
CITIES. OTHERWISE...SUNNY. NEAR NORMAL TEMPS. ISOLATED TSTMS
SHOULD DEVELOP FROM THE SAND HILLS SW TO NEAR IML IN THE 4-6 PM
TIME FRAME. THESE COULD EVENTUALLY THREATEN AREAS FROM ODX-LXN.
TONIGHT: P-M/CLOUDY AS CLOUD DEBRIS FROM TSTMS OVERTAKES THE
AREA. INDICATIONS FROM THE 03Z SREF AND VARIOUS MODELS ARE THAT
SOME OF THE TSTM ACTIVITY THAT DEVELOPS LATE THIS AFTERNOON COULD
LINGER INTO THE NIGHT...SUSTAINED BY A 30 KT LOW-LVL JET.
THE 06Z NAM WAS NOT NEARLY AS AGGRESSIVE WITH ITS QPF AS THE 00Z
RUN.
STORMS THAT DEVELOP LATE THIS AFTERNOON WILL BE FAIRLY SLOW
MOVERS...E AROUND 20 KTS. CAN`T RULE OUT SEVERE WX. MLCAPE WILL BE
SUBSTANTIAL (3000-4000 J/KG) WITH TEMPS AROUND 90F...DWPTS IN THE
LOW 70S AND MID-LVL LAPSE RATES OF 7 DEG C/KM. THE OVERALL LACK OF
FORCING WILL KEEP STORMS FEW AND FAR BETWEEN...BUT WHATEVER DOES
DEVELOP COULD BE SEVERE FOR A TIME PROBABLY PRIOR TO 10 PM. DEEP
LAYER SHEAR 40-45 KTS. SUPERCELL STORM STRUCTURES WILL BE
POSSIBLE. SUPERCELL STORM MOTION COULD EVEN BE SLOWER.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 437 AM CDT THU JUL 23 2015
FRIDAY WILL BE THE HOTTEST DAY OF THE WEEK AND WE WILL
BE FLIRTING WITH HEAT ADVISORY CRITERIA FOR MOST LOCATIONS SOUTH AND
EAST OF THE TRI-CITIES. THE WEEKEND WILL REMAIN HOT WITH HIGHS A FEW
DEGREES ABOVE NORMAL RIGHT INTO MONDAY. WE COULD COOL BACK A COUPLE
DEGREES TO AROUND NORMAL TEMPERATURES BY TUESDAY AND WEDNESDAY.
THERE WILL BE SEVERAL CHANCES FOR THUNDERSTORMS IN THE WEEK AHEAD
WITH ONE OF THE BETTER CHANCES BEING FRIDAY NIGHT.
FRIDAY...A LARGE UPPER LEVEL RIDGE WILL BE CENTERED OVER NORTH TEXAS
AND A WEAK VORT MAX WILL BE SLIDING EAST ACROSS NEBRASKA ALONG THE
NORTHERN PERIPHERY OF THIS UPPER HIGH BY LATE IN THE DAY. THERE WILL
BE A WEAK SFC LOW/TROUGH AXIS LOCATED FROM SOUTHWEST TO NORTHEAST
ACROSS OUR FORECAST AREA BY AFTERNOON/EARLY EVENING. EXPECT A LIGHT
NORTHEAST WIND ACROSS OUR NORTHERN ZONES NORTH OF THIS BOUNDARY AND
A SOUTHERLY WIND OVER OUR KANSAS COUNTIES AND FAR SOUTHEASTERN
NEBRASKA COUNTIES SOUTH OF THIS SFC TROUGH. THERE WILL BE A LOT OF
LOW LEVEL MOISTURE POOLING ALONG THE SFC BOUNDARY...ESPECIALLY GIVEN
THE TIME OF YEAR WITH A SIGNIFICANT AMOUNT OF CORN
EVAPOTRANSPIRATION. SFC DEWPOINTS WILL LIKELY BE IN THE MID TO UPPER
70S WITH A FEW SITES POSSIBLY EVEN SEEING AN 80F DEWPOINT. THIS WILL
RESULT IN VERY HIGH INSTABILITY. WIND SHEAR IS RATHER
MARGINAL...ESPECIALLY AS YOU HEAD SOUTH INTO KANSAS CLOSER TO THE
UPPER HIGH. HOWEVER...THERE IS A PRETTY GOOD UPPER LEVEL JET FOR
THIS TIME OF YEAR AT 50 TO 55 KTS OVER SOME OF OUR NEBRASKA
COUNTIES. EXPECT THUNDERSTORMS WILL FORM ALONG THE SFC TROUGH LATE
IN THE AFTERNOON WITH MAX HEATING. THE LOW LEVEL JET WILL STRENGTHEN
AFTER SUNSET WITH THE NOSE OF THE LOW LEVEL JET SUPPORTING STRONG
THUNDERSTORMS WELL INTO THE EVENING ACROSS PORTIONS OF OUR FORECAST
AREA. SEVERE WIND AND HAIL WILL BE POSSIBLE LATE FRIDAY AFTERNOON
INTO THE EVENING HOURS.
GIVEN THE HIGH DEWPOINTS AND HIGH TEMPERATURES...HEAT INDEX VALUES
STAND A DECENT CHANCE OF REACHING OUR 105F ADVISORY THRESHOLD RIGHT
ALONG AND SOUTH OF THE TROUGH AXIS FRIDAY AFTERNOON. A HEAT ADVISORY
WILL LIKELY BE NEEDED ACROSS PORTIONS OF OUR FORECAST AREA IF THIS
TREND CONTINUES.
SATURDAY AND SUNDAY...EXPECT OLD OUTFLOW BOUNDARIES ACROSS THE
FORECAST AREA FROM FRIDAY NIGHT AND SATURDAY NIGHT THUNDERSTORMS
WILL BE A FOCUSING MECHANISM FOR NEW AFTERNOON/EVENING THUNDERSTORMS
BOTH DAYS THIS WEEKEND. THE LOW LEVEL JET WILL AGAIN BE WELL
POSITIONED FOR DEVELOPING/MAINTAINING THUNDERSTORMS DURING THE
EVENING AND OVERNIGHT HOURS BOTH FRIDAY NIGHT AND SATURDAY NIGHT.
THEREFORE...EXPECT AT LEAST SEVERAL THUNDERSTORMS IN THE AREA
PRIMARILY DURING THE LATE AFTERNOON/EVENING/OVERNIGHT HOURS.
THUNDERSTORM CHANCES WILL BE HIGHEST ON SATURDAY...BUT MAY NEED TO
INCREASE CHANCES FOR THE SUNDAY EVENING TIME FRAME BASED ON THE
LATEST 00Z RUN OF THE ECMWF. TEMPERATURES WILL REMAIN HOT ESPECIALLY
AS YOU HEAD SOUTH INTO KANSAS AND NEARER THAT BIG UPPER RIDGE THAT
WILL CONTINUE TO BE PARKED OUT OVER TEXAS.
MONDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE WHEN IT COMES TO RAIN
CHANCES IS FAIRLY LOW. FORECAST MODELS ARE ALL OVER THE PLACE ON IF
WE WILL OR WILL NOT SEE SOME RAIN DURING THIS OUTER PERIOD. GENERAL
FEELING IS THAT WE WILL CONTINUE TO SEE RAIN CHANCES ACROSS OUR
FORECAST AREA AS UPPER TROUGHS SWING THROUGH RIDING JUST NORTH OF
THE SOUTHERN PLAINS UPPER RIDGE...WHICH SHOULD PLACE THUNDERSTORMS
IN OUR GENERAL AREA. HIGH TEMPERATURES THROUGH THE PERIOD REFLECT
THE SUPERBLEND OF FORECAST MODELS...WHICH WOULD BE RIGHT AROUND
NORMAL TO A FEW DEGREES ABOVE NORMAL ON MONDAY AND THEN NEAR NORMAL
TO A FEW DEGREES BELOW NORMAL BY TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THU NIGHT)
ISSUED AT 1227 AM CDT THU JUL 23 2015
SIGNIFICANT AVIATION WX: NONE
REST OF TONIGHT: VFR AND ESSENTIALLY SKC. SE WINDS 10 KTS OR LESS.
CONFIDENCE: HIGH
THU: VFR WITH JUST A FEW PATCHES OF ALTOCU AROUND 13K FT DRIFTING
THRU. SE-S WINDS 10-15 KTS. CAN`T RULE OUT A GUST OR TWO CLOSE TO
20 KTS. CONFIDENCE: HIGH
THU THRU 06Z: VFR WITH MULTI-LAYERED CLOUDS INVADING...BLOW-OFF
FROM UPSTREAM TSTMS. THERE IS A CHANCE TSTMS COULD MOVE THRU THE
TERMINALS AFTER 06Z. SE WINDS UNDER 10 KTS. CONFIDENCE: MEDIUM
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
417 AM CDT THU JUL 23 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 417 AM CDT THU JUL 23 2015
ALOFT: THE PATTERN THAT HAS BEEN IN PLACE SINCE THE BEGINNING OF
THE MONTH REMAINS LOCKED IN. SUBTROPICAL HIGH PRES WAS OVER TX
WITH TROFS OVER THE ERN AND WRN USA. THERE WILL BE NO CHANGE THRU
TONIGHT. SYNOPTIC FORCING WILL BE NIL.
SURFACE: HIGH PRES WAS OVER THE MIDWEST AND OH VALLEY AND WILL
REMAIN PARKED THERE THRU TONIGHT. LOW PRES WAS ADVANCING THRU
CNTRL CANADA THIS MORNING. ITS COOL FRONT EXTENDED SW INTO THE NRN
ROCKIES...BISECTING MT/ID. THIS FRONT WILL MOVE INTO THE NRN
PLAINS TODAY...WITH ITS TAIL END ENTERING NRN/WRN NEB TONIGHT.
A WEAK/SUBTLE SHORTWAVE TROF /BEST SEEN AT 700 MB/ APPEARS TO BE
RESPONSIBLE FOR THE FEW SHWRS/TSTMS THAT HAVE BEEN ON-GOING THRU
THE NIGHT ALONG THE SD/NEB BORDER. AN ISOLATED CELL OR TWO HAS
TRIED TO DEVELOP AT TIMES N-NW OF ODX. VARIOUS MODELS AND THE HI-
RES RAP ENSEMBLE SUGGEST THESE SHWRS/TSTMS COULD INCREASE IN
COVERAGE AND BUILD DOWN INTO AREAS E OF HWY 281.
IR SATELLITE DOES SHOW A N-S ORIENTED BAND OF CLOUDS HAS DEVELOPED
AND BVN/AUH/JYR ALL NOW HAVE CIGS AROUND 6-7K FT.
TODAY: COULD SEE AN ISOLATED SHWR/TSTM EARLY N AND E OF THE TRI-
CITIES. OTHERWISE...SUNNY. NEAR NORMAL TEMPS. ISOLATED TSTMS
SHOULD DEVELOP FROM THE SAND HILLS SW TO NEAR IML IN THE 4-6 PM
TIME FRAME. THESE COULD EVENTUALLY THREATEN AREAS FROM ODX-LXN.
TONIGHT: P-M/CLOUDY AS CLOUD DEBRIS FROM TSTMS OVERTAKES THE
AREA. INDICATIONS FROM THE 03Z SREF AND VARIOUS MODELS ARE THAT
SOME OF THE TSTM ACTIVITY THAT DEVELOPS LATE THIS AFTERNOON COULD
LINGER INTO THE NIGHT...SUSTAINED BY A 30 KT LOW-LVL JET.
THE 06Z NAM WAS NOT NEARLY AS AGGRESSIVE WITH ITS QPF AS THE 00Z
RUN.
STORMS THAT DEVELOP LATE THIS AFTERNOON WILL BE FAIRLY SLOW
MOVERS...E AROUND 20 KTS. CAN`T RULE OUT SEVERE WX. MLCAPE WILL BE
SUBSTANTIAL (3000-4000 J/KG) WITH TEMPS AROUND 90F...DWPTS IN THE
LOW 70S AND MID-LVL LAPSE RATES OF 7 DEG C/KM. THE OVERALL LACK OF
FORCING WILL KEEP STORMS FEW AND FAR BETWEEN...BUT WHATEVER DOES
DEVELOP COULD BE SEVERE FOR A TIME PROBABLY PRIOR TO 10 PM. DEEP
LAYER SHEAR 40-45 KTS. SUPERCELL STORM STRUCTURES WILL BE
POSSIBLE. SUPERCELL STORM MOTION COULD EVEN BE SLOWER.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 417 AM CDT THU JUL 23 2015
THIS SECTION WILL UPDATE SHORTLY.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THU NIGHT)
ISSUED AT 1227 AM CDT THU JUL 23 2015
SIGNIFICANT AVIATION WX: NONE
REST OF TONIGHT: VFR AND ESSENTIALLY SKC. SE WINDS 10 KTS OR LESS.
CONFIDENCE: HIGH
THU: VFR WITH JUST A FEW PATCHES OF ALTOCU AROUND 13K FT DRIFTING
THRU. SE-S WINDS 10-15 KTS. CAN`T RULE OUT A GUST OR TWO CLOSE TO
20 KTS. CONFIDENCE: HIGH
THU THRU 06Z: VFR WITH MULTI-LAYERED CLOUDS INVADING...BLOW-OFF
FROM UPSTREAM TSTMS. THERE IS A CHANCE TSTMS COULD MOVE THRU THE
TERMINALS AFTER 06Z. SE WINDS UNDER 10 KTS. CONFIDENCE: MEDIUM
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS ELKO NV
312 PM PDT THU JUL 23 2015
.SYNOPSIS...TEMPERATURES WILL CONTINUE TO RUN SLIGHTLY BELOW
NORMAL FOR THE THIRD WEEK OF JULY. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND INTO THE EVENING. DRIER WEATHER
EXPECTED THIS WEEKEND.
&&
.SHORT TERM...TODAY THROUGH SATURDAY. KLRX CONTINUES TO BE
CONVECTIVE OVER THE EASTERN PORTION OF THE CWA. THE HRRR HAS BEEN
A TAD BIT TOO EAGER WITH THE DEVELOPMENT OF TSRA OVER THE
CWA...BUT SEEMS TO HAVE FEWER CONVECTIVE FEEDBACK ISSUES THAN BOTH
THE GFS AND THE NAM...MAKING IT THE MODEL OF CHOICE FOR TODAY. AS
TIME ELAPSES...NCEP GUIDANCE DRIES MUCH OF THE CWA...WITH ONE
CAVEAT...NORTHERN ELKO COUNTY. MORE BELOW NORMAL TEMPS
ANTICIPATED THIS FORECAST PERIOD. FOR ELKO...THE MEAN MAX TEMP FOR
JULY 24TH AND 25TH IS 92F...WENT FOR A HIGH OF 85F ON THE 24TH AND
88F ON THE 25TH. FOR WINNEMUCCA...THE MEAN MAX TEMP IS 95F FOR
BOTH THE 24TH AND 25TH OF JULY...PROGGED A HIGH OF 86F AND 88F
RESPECTIVELY.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY. TEMPS WILL BE BELOW
AVERAGE DURING THE FIRST PART OF THE WEEK...BEFORE RETURNING TO
ABOVE/NEAR AVERAGE.
SUNDAY AND MONDAY WILL FEATURE A TROUGH CLIPPING NORTHERN NEVADA.
THE MODELS HAVE TRENDED DEEPER WITH THIS SYSTEM...WHICH COULD BRING
AN UNSEASONABLY STRONG COLD FRONT TO NORTHERN NEVADA. THIS WOULD
DROP DAYTIME HIGHS TO WELL BELOW AVERAGE FOR MONDAY AND TUESDAY.
MANY LOCATIONS WILL SEE HIGHS IN THE 70S/80S. SOME OF THE HIGHER
VALLEYS ACROSS THE NORTH...COULD DIP INTO THE 60S. OVERNIGHT LOWS
WILL BE QUITE COOL AS WELL. PLACES LIKE CHARLESTON AND WILD HORSE
COULD SEE LOWER 30S FOR LOWS ON MON/TUE.
BY THE MIDDLE TO END OF NEXT WEEK...HEIGHTS WILL BEGIN TO RISE. THIS
WILL RESULT IN WARMING TEMPS AND DRIER CONDITIONS. MODELS STILL HINT
AT SOME MONSOON MOISTURE SNEAKING INTO SOUTHERN NEVADA...BUT
CONFIDENCE REMAINS FAIR AT BEST.
&&
.AVIATION...ALREADY HAD -TSRA AT KEKO TODAY. EXPECT ADDITIONAL
-SHRA/VCTS THROUGH THE REST OF THE AFTERNOON AND INTO THE EARLY
EVENING. KELY/KWMC/KTPH WILL STAY DRY.
&&
.FIRE WEATHER...MOST OF THE LIGHTNING TODAY HAS OCCURRED IN THE
NORTHERN HALF OF 469...ALTHOUGH ISOLATED CELLS HAVE POPPED UP AS FAR
WEST AS 454. EXPECTING THE DYNAMICS TO GRADUALLY SHIFT NORTH AND
EAST. EXPECT THE SHOWERS AND THUNDERSTORMS TO TAPER OFF FRIDAY.
SATURDAY AND SUNDAY EXPECTING DRY CONDITIONS. NEXT
WEEK...EXPECTING UPPER LEVEL HEIGHTS TO RISE AS RIDING MOVES INTO
THE EASTPAC...HOWEVER...THE GFS DOES NOT EVEN HINT AT H5 POSITIVE
ANOMALIES UNTIL DAY 8...AND THAT IS ONLY FOR WESTERN NV. SUFFICE
TO SAY...CLIMATE-WISE...DEFINITELY NOT A TYPICAL MONTH OF JULY.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
97/94/94/97
AREA FORECAST DISCUSSION
NWS RALEIGH NC
235 PM EDT THU JUL 23 2015
.SYNOPSIS...A WAVE OF LOW PRESSURE DEVELOPING ALONG A STALLED
FRONTAL ZONE IN UPSTATE SOUTH CAROLINA WILL TRACK SLOWLY EAST TOWARD
THE CAROLINA COAST THIS AFTERNOON INTO TONIGHT...THEN STALL OFFSHORE
THE SOUTHEAST COAST OVER THE WEEKEND AS WEAK HIGH PRESSURE EXTENDS
INTO THE REGION FROM THE NORTH.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 930 AM THURSDAY...
FORECAST LARGELY ON TRACK WITH SMALL SPATIAL/TEMPORAL MODIFICATIONS.
SEVERAL CLUSTERS OF SHOWERS/STORMS ARE PROGRESSING ESE OVER THE FAR
NRN AND NE CWA... WITHIN A BAND OF ENHANCE LOW LEVEL MOISTURE
CONVERGENCE ALONG A TIGHT THETA-E GRADIENT. PW VALUES OVER CENTRAL
NC HAVE SURGED WELL BACK UP ABOVE NORMAL IN THE LAST 12 HRS...
FACILITATING A VOLATILE ATMOSPHERE WITH SCATTERED TO NUMEROUS
SHOWERS AND STORMS FUELED BY WEAK TO MODERATE INSTABILITY...
IMPROVING DYNAMIC FORCING FOR ASCENT AS A MID LEVEL WAVE TRACKS FROM
TN ACROSS THE CAROLINAS TODAY... AND IMPROVING KINEMATICS AS WELL-
DEFINED SURFACE LOW PRESSURE PERSISTS ALONG THE FRONTAL ZONE OVER
NRN SC. THE LATEST HRRR RUNS AND THE NSSL WRF HAVE DONE A GOOD JOB
WITH CONVECTION SO FAR THIS MORNING... AND BOTH SHIFT THE GREATER
STORM COVERAGE (50-60%) FROM THE NE CWA TO THE SOUTHEAST THIS
AFTERNOON... WHERE LOW LEVEL MASS CONVERGENCE ENE OF THE LOW WILL BE
HIGHEST WITH THE BETTER POTENTIAL FOR INSTABILITY. WILL RETAIN A
TREND TO LIKELY POPS IN THIS AREA. EFFECTIVE DEEP LAYER SHEAR
REMAINS MARGINAL AT 20-30 KTS BUT STILL ENOUGH FOR A THREAT OF
ISOLATED STRONG TO DAMAGING WIND GUSTS WITH ANY CELLS. MODELS THEN
REDEVELOP SHOWERS AND ISOLATED STORMS BACK OVER THE SW CWA THIS
EVENING... AS THE MID LEVEL WAVE MOVES IN... IN CONJUNCTION WITH
FORMATION OF A NEW LEE LOW OVER UPSTATE SC. WILL KEEP THE TREND BACK
TOWARD HIGH POPS THIS EVENING IN OUR SW... SPREADING EAST
OVERNIGHT... ALTHOUGH WILL RE-EVALUATE POTENTIAL COVERAGE THIS
AFTERNOON. THE CLOUDS/PRECIP AND LIGHT NE FLOW ARE BOUND TO HOLD
TEMPS DOWN BELOW NORMAL TODAY IN THE NE. EXPECT HIGHS FROM THE LOW
80S N TO NEAR 90 SOUTH... PREDICATED ON GETTING AT LEAST SOME
ISOLATION NORTH THIS AFTERNOON BEHIND THE ONGOING CONVECTION. -GIH
PREVIOUS DISCUSSION FROM 400 AM... OVERVIEW: DIFFICULT FORECAST. 06Z
SPC MESOANALYSIS AND REMOTE SENSING DATA INDICATED NUMEROUS SMALL
AMPLITUDE WAVES TRACKING EAST/ESE ALONG THE SOUTHERN FRINGE OF THE
WESTERLIES THROUGH THE TN VALLEY THIS MORNING...DOWNSTREAM OF A
PRONOUNCED UPPER LEVEL RIDGE ANCHORED OVER THE LOWER MIDWEST. IN
RESPONSE TO DPVA ATTENDANT AN APPROACHING DISTURBANCE...A WEAK
SURFACE LOW IS DEVELOPING ALONG A STALLED FRONTAL ZONE SITUATED
ACROSS UPSTATE SC/SOUTHWEST NC (NEAR SHELBY NC) AND WEAK WARM
ADVECTION HAS COMMENCED OVER CENTRAL NC AS 925-850 MB FLOW BACKS IN
ADVANCE OF THE WAVE. WITH ADDITIONAL SMALL AMPLITUDE WAVES PRESENT
UPSTREAM AND A WIDE VARIETY OF MECHANISMS (CONVECTION /LATENT HEAT
RELEASE/ IN PARTICULAR) THAT CAN AFFECT THE EVOLUTION OF LOW-LEVEL
HEIGHT/WIND/MOISTURE FIELDS...CONFIDENCE REMAINS LOW WITH REGARD TO
CONVECTIVE COVERAGE/TIMING TODAY INTO TONIGHT. QUALITATIVELY...GIVEN
THE PATTERN ONE WOULD EXPECT INCREASED CLOUD COVER...CHANCES FOR
CONVECTION...AND AT OR BELOW NORMAL TEMPERATURES.
CONVECTION: IN RESPONSE TO WEAK LOW-LEVEL CONVERGENCE...WARM
ADVECTION... APPROACHING DPVA... AND NOCTURNAL DESTABILIZATION
(DRIVEN BY LOW-LEVEL MOISTURE ADVECTION)...ISOLATED ELEVATED
CONVECTION HAS ALREADY DEVELOPED IN VICINITY OF HWY 64. THE LATEST
RAP GUIDANCE SUGGESTS ELEVATED CONVECTION WILL INCREASE IN COVERAGE
AND INTENSITY ALONG/NORTH OF HWY 64 THROUGH 15Z AS THE EASTERN-MOST
UPPER LEVEL DISTURBANCE APPROACHES...LOW-LEVEL CONVERGENCE
STRENGTHENS /FLOW BACKS/...AND MOISTURE ADVECTION AIDS IN FURTHER
DESTABILIZATION. AS THE LEAD DISTURBANCE PROGRESSES EAST ACROSS
CENTRAL NC BY EARLY AFTERNOON...THE DEVELOPING SFC-H925 LOW IS
EXPECTED TO WEAKEN/BROADEN OVER WESTERN NC...WITH AN ATTENDANT
WEAKENING OF WARM ADVECTION AS LOW-LEVEL FLOW VEERS TO THE SOUTH AND
WEAKENS ACROSS CENTRAL NC. HOWEVER...WEAK LOW-LEVEL CONVERGENCE AND
DIURNAL DESTABILIZATION WITHIN THE WARM SECTOR SHOULD BE SUFFICIENT
FOR ANY ONGOING CONVECTION TO PERSIST DURING THE EARLY/MID
AFTERNOON...MOST LIKELY IN THE FORM OF SFC-BASED CONVECTION
PROPAGATING SOUTHEAST (ALONG OUTFLOW) THROUGH THE COASTAL PLAIN INTO
EASTERN/COASTAL NC DURING THE AFTERNOON.
SEVERE: THOUGH SFC-BASED CONVECTION WILL BECOME INCREASINGLY LIKELY
ALONG/SOUTH OF HWY 64 AS THE WARM SECTOR SLOWLY ADVANCES FROM CAPE
FEAR INTO THE SANDHILLS 08-12Z...CONVECTION SHOULD REMAIN ELEVATED
IN NATURE NORTH OF THE I-85 CORRIDOR. BY OR SHORTLY AFTER SUNRISE...
MARGINAL TO MODERATE INSTABILITY AND DEEP LAYER SHEAR ~30 KT WILL
CONTRIBUTE TO SUPERCELL COMPOSITE PARAMETER VALUES AS HIGH AS 1-3
(PRIMARILY SOUTH AND EAST OF THE TRIANGLE)...INDICATING THAT THE
ENVIRONMENT WILL BE BASICALLY SUPPORTIVE OF SEVERE WEATHER DURING
THE MORNING...PRIMARILY IN THE FORM OF WET DOWNBURSTS VIA A
COMBINATION OF MOMENTUM TRANSPORT (20-25 KT MID-LEVEL FLOW) AND
PRECIP LOADING...PARTICULARLY WITH PWAT VALUES AS HIGH AS 2.00-
2.25". WEAK LOW-LEVEL SPEED SHEAR ON THE EASTERN PERIPHERY OF THE
SFC LOW SHOULD EFFECTIVELY LIMIT 0-1 KM SRH VALUES TO NO HIGHER THAN
50-100 M2/S2 IN CENTRAL NC THIS MORNING...THOUGH VALUES AS HIGH AS
150-200 M2/S2 WILL BE POSSIBLE THIS AFTERNOON IN COASTAL NC...
PERHAPS INCLUDING PORTIONS OF THE SE COASTAL PLAIN. WITH THIS IN
MIND...AN ISOLATED TOR (BRIEF/LOW-END VARIETY)...CANNOT BE RULED OUT
WITH VIGOROUS UPDRAFTS (IF ANY) THIS AFTERNOON...PRIMARILY FAR SE
COASTAL PLAIN (I.E. SAMPSON/WAYNE/CUMBERLAND). -VINCENT
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 311 AM THURSDAY...
THE WEAK MID/UPPER LOW WILL SLOWLY DRIFT DEEP INTO THE SE STATES
FRIDAY. MOST IF NOT ALL THE SCATTERED SHOWERS AND THUNDERSTORMS
SHOULD BE IN OUR SE COUNTIES EARLY IN THE DAY... BEFORE SHIFTING ON
SOUTHWARD AND REDEVELOPING WITH DIURNAL HEATING AGAIN FRIDAY
AFTERNOON. OTHERWISE... PARTLY SUNNY WITH HIGHS IN THE MID TO UPPER
80S. PARTLY CLOUDY TO MOSTLY CLEAR SKIES EXPECTED FRIDAY NIGHT WITH
LOWS IN THE MID TO UPPER 60S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 230 PM THURSDAY...
HIGH PRESSURE WILL BUILD DOWN THE APPALACHIANS...SUPPRESSING A
SURFACE BOUNDARY ALL THE WAY DOWN TO NEAR THE GULF COAST. THIS
PATTERN WILL PERSIST THROUGH AT LEAST THE END OF THE WEEKEND...
LEADING TO MOSTLY DRY CONDITIONS. BY EARLY NEXT WEEK THE HIGH WILL
BEGIN TO SHIFT OFFSHORE...BUT EXACTLY HOW QUICKLY IS STILL
UNCERTAIN. REGARDLESS...MOISTURE AND INSTABILITY WILL GRADUALLY
INCREASE...LEADING TO AN INCREASE IN PRECIP CHANCES. IN ADDITION...
THE PERSISTENT MID/UPPER LEVEL RIDGE THAT HAS BEEN ANCHORED NEAR
TEXAS...IS PROGGED TO AMPLIFY INTO THE MID MISSISSIPPI RIVER VALLEY
WHICH WILL PLACE OUR REGION UNDER DEEP NORTHWESTERLY FLOW. THEREFORE
MUCH OF OUR CONVECTIVE COVERAGE WILL LIKELY BE DICTATED BY UPSTREAM
MCS/MCVS WHICH ARE IMPOSSIBLE TO TIME THIS FAR OUT. ALTHOUGH...
MODELS ARE KEYING IN ON A SYSTEM LATE MONDAY...BUT THIS TIMING IS
LIKELY TO CHANGE. THUS...WILL JUST SHOW NEAR NORMAL POPS (LOW END
CHANCE) FOR ALL OF NEXT WEEK. TEMPS WILL BE NEAR NORMAL FOR MUCH OF
THE PERIOD BEFORE TRENDING TO SLIGHTLY ABOVE NORMAL BY THE MIDDLE OF
NEXT WEEK.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1235 PM THURSDAY...
OF MOST IMMEDIATE AVIATION CONCERN IS THE HIGH PROBABILITY OF
BRIEFLY VERY POOR (LIFR) CONDITIONS (LOW CIGS AND VSBYS WITH
TORRENTIAL RAIN AND GUSTY WINDS WITH ISOLATED WET MICROBURSTS
POSSIBLE) IN AND NEAR STORMS IN THE NEXT HOUR OR TWO... MOST LIKELY
TO AFFECT RWI/FAY THROUGH THIS AFTERNOON. SUCH CONDITIONS RECENTLY
IMPACTED RDU... HOWEVER RDU SHOULD SEE A RELATIVE LULL IN STORMS
THROUGH THE AFTERNOON... WITH PERHAPS SOME SHOWERS AFTER NIGHTFALL.
OTHERWISE... MVFR TO IFR CIGS OVER MUCH OF CENTRAL NC (ALL BUT FAY)
WILL SLOWLY LIFT BUT ARE LIKELY TO REMAIN SUB-VFR AT INT/GSO/RDU
THROUGH MID AFTERNOON... THEN INCHING UP INTO LOW-END VFR CIGS AFTER
20Z... ALTHOUGH SCT-BKN MVFR CLOUDS MAY LINGER AT RDU AND PERHAPS
GSO. FAY IS LIKELY TO BE ADVERSELY IMPACTED BY CLUSTERS OF SUB-VFR
SHOWERS AND STORMS FOR THE MAJORITY OF THE 18Z-02Z PERIOD. AFTER
02Z... IFR STRATUS/FOG IS LIKELY AT RDU/FAY/RWI THROUGH THE
OVERNIGHT... WITH A MUCH LOWER CHANCE AT INT/GSO. SCATTERED SHOWERS
MAY AFFECT INTO/GSO/FAY OVERNIGHT... WITH A MUCH LOWER CHANCE AT
RDU/RWI. AFTER 14Z... ANY SUB-VFR CONDITIONS ARE EXPECTED TO IMPROVE
TO VFR AREAWIDE... AS HIGH PRESSURE NOSES IN FROM THE NORTH.
LOOKING BEYOND 18Z FRI... VFR CONDITIONS SHOULD DOMINATE AT ALL
CENTRAL NC TERMINALS AS HIGH PRESSURE CONTINUES TO BUILD IN FROM THE
NORTH AND NE THROUGH THE WEEKEND. STORM CHANCES RETURN LATE MON AND
ESPECIALLY MON NIGHT INTO TUE AS A DISTURBANCE DROPS IN FROM THE
NORTHWEST. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...PWB
LONG TERM...KRD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
109 PM EDT THU JUL 23 2015
.SYNOPSIS...
LOW PRESSURE OVER NORTHERN SOUTH CAROLINA WILL MOVE EAST ALONG A
STALLED FRONT TODAY AND OFF THE COAST TONIGHT. THIS LOW WILL PUSH
THE FRONT INTO GEORGIA FOR THIS WEEKEND. HIGH PRESSURE WILL BUILD
DOWN FROM THE NORTH...WITH A DRYING TREND EXPECTED THIS WEEKEND
INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 110 PM THURSDAY...UPDATED FORECAST WITH ISSUANCE OF A
SEVERE THUNDERSTORM WATCH FOR THE ENTIRE AREA...GOOD UNTIL 8 PM.
PREVIOUS DISCUSSIONS FOLLOW:
ANALYSIS OF MORNING SOUNDINGS AND LATEST GUIDANCE CONFIRM EARLIER
FORECAST OF AN ACTIVE WEATHER DAY...ESPECIALLY THIS AFTERNOON AND
EVENING...WITH THE PRIMARY THREATS BEING HEAVY RAIN AND UNUSUALLY
FREQUENT LIGHTNING. DAMAGING WIND GUSTS ARE ALSO A POSSIBILITY. NO
CHANGES NEEDED YET TO THE FORECAST. PREVIOUS DISCUSSION FOLLOWS:
LOW PRESSURE CENTERED OVER THE SC SANDHILLS WILL MOVE EASTWARD
ALONG A STATIONARY FRONT TODAY...EXITING INTO THE ATLANTIC OCEAN
TONIGHT. MODELS ARE ALMOST UNANIMOUS IN THEIR DEPICTION OF A LARGE
CLUSTER OF THUNDERSTORMS DEVELOPING WITHIN A REGION OF LOW-LEVEL
CONVERGENCE AND LARGE INSTABILITY OVER SOUTHERN NORTH CAROLINA
JUST NORTH OF THE STATIONARY FRONT LATE THIS MORNING. SURFACE CAPE
IS PREDICTED TO GROW AS LARGE AS 3000 J/KG WITH LIFTED INDICES TO
-6. 700 MB WINDS INCREASING TO 25 KT SHOULD INCREASE BULK SHEAR
VALUES JUST ENOUGH TO PRODUCE ORGANIZED MULTICELLULAR STORMS
TODAY...WITH COLD POOL EFFECTS LIKELY PUSHING THE CLUSTER
SOUTHEASTWARD ACROSS THE CAPE FEAR AREA EARLY THIS AFTERNOON AND
INTO NORTHEASTERLY SOUTH CAROLINA BY MID TO LATE AFTERNOON.
IMPACTS FROM THESE STORMS COULD BE CONSIDERABLE. COMPUTED
EQUILIBRIUM PARCEL HEIGHTS NEAR 50000 FT AND LOTS OF INSTABILITY
ABOVE THE -20C LEVEL INDICATES THESE STORMS COULD BE ENORMOUS
LIGHTNING PRODUCERS WITH PLENTY OF ICE/GRAUPEL GENERATION ALOFT.
ALTHOUGH NO DRY LAYERS ARE EVIDENT IN FORECAST SOUNDINGS
PRECIPITATION LOADING RESULTING FROM SUCH VIGOROUS CONVECTION
SHOULD PRODUCE GUSTY WINDS...PARTICULARLY AS THE STORMS ARE SHOWN
IN THE HIGH RESOLUTION WRF-NMM...WRF-ARW...AND HRRR MODELS TO FORM
A LARGE MASSED OUTFLOW PUSHING SOUTHEASTWARD TO THE COAST. WITH
THE SYNOPTIC FRONT STALLED ACROSS THE AREA AND ANTICIPATED
BOUNDARY COLLISIONS THE STORMS SHOULD ALSO BE HEAVY RAIN MAKERS
WITH LOCALIZED FLOODING POSSIBLE. FORECAST RAIN CHANCES HAVE BEEN
INCREASED TO 80 PERCENT ACROSS SE NORTH CAROLINA...FOCUSED ON THE
NOON-4 PM TIMEFRAME.
CONVECTION SHOULD TAKE SEVERAL ADDITIONAL HOURS TO PROPAGATE
SOUTHWARD AND AFFECT NE SOUTH CAROLINA WHICH WILL BE LOCATED SOUTH
OF THE STATIONARY FRONT. THIS MEANS SEVERAL ADDITIONAL HOURS OF
HOT SUNSHINE...AND TEMPERATURES HERE WILL RISE INTO THE MID TO
UPPER 90S. FORECAST HEAT INDICES ARE JUST BELOW 105-DEGREE HEAT
ADVISORY CRITERIA ACROSS GEORGETOWN...WILLIAMSBURG AND SOUTHERN
FLORENCE COUNTIES.
AN UPPER LEVEL DISTURBANCE CURRENTLY PRODUCING THUNDERSTORMS OVER
CENTRAL TENNESSEE WILL REACH THE EASTERN CAROLINAS THIS EVENING.
THIS COULD HELP CONVECTIVE ACTIVITY TO PERSIST INTO THE EVENING
HOURS EVEN AFTER THE ATMOSPHERE PRETTY MUCH OVERTURNS DURING THE
AFTERNOON. THE LOW WILL SCOOT EASTWARD ALONG THE FRONT OFFSHORE
AFTER MIDNIGHT WITH SURFACE WINDS TURNING NORTHWESTERLY...QUITE AN
ODD DIRECTION FOR THE CAROLINAS IN THE MIDDLE OF SUMMER. THIS IS
THE THIRD COLD FRONTAL PASSAGE OF JULY!
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LATEST MODELS SHOW LOW JUST OFF THE CAPE
FEAR COAST FRI MORNING. EXPECT BEST CONVECTION OVER THE COASTAL
WATERS WITH MOST AREAS SEEING A DEEP FLOW OF DRIER AIR ADVECTING
IN FROM THE NORTH. MID TO UPPER TROUGH WILL PUSH LOW PRESSURE
ALONG LINGERING BOUNDARY SOUTH AND EAST OF AREA THROUGH THE
DAY...BUT PLENTY OF RESIDUAL LOW LEVEL MOISTURE FROM PREVIOUS DAYS
CONVECTION WILL SLOW CLEARING AND COMBINE WITH CONVERGENCE
ASSOCIATED WITH LOW AND OTHER LOCALIZED BOUNDARIES SUCH AS THE SEA
BREEZE TO PRODUCE SOME SHWRS/TSTMS. LOOKS LIKE BEST CHC WILL MOVE
SOUTH THROUGH THE DAY AS HIGH PRESSURE BEGINS TO BUILD DOWN FROM
THE NORTH BUT MAY NOT BE FAST ENOUGH TO ELIMINATE POPS FROM
FORECAST. NAM SHOWS MAIN FOCUS OF CONVECTION ALONG COASTAL SOUTH
CAROLINA WHERE BEST CONVERGENCE SHOULD BE AS WE DEVELOP A N-NE
FLOW. MAY SEE ENOUGH SUBSIDENCE AND DRY AIR THROUGH THE MID TO
UPPER LEVELS BY LATE FRI TO ALLOW FOR ONLY A DECENT STRATOCU FIELD
OVER NC. PCP WATER VALUES OVER 2 INCHES EARLY FRI MORNING WILL
DROP DOWN CLOSE TO AN INCH BY SAT MORNING. LINGERING CLOUDS AND
PCP WILL KEEP TEMPS IN THE 80S MOST OF THE DAY BUT PLACES THAT SEE
SOME SUN MAKE AN APPEARANCE WILL REACH CLOSE TO 90.
BY LATE FRI INTO FRI NIGHT...PLENTY OF DRY AIR AND SUBSIDENCE
THROUGH THE MID TO UPPER LEVELS WILL REACH DOWN OVER THE FORECAST
AREA AS DRY HIGH PRESSURE AT THE SFC NOSES DOWN FROM THE NORTH.
WILL SHOW CLEARING AT THIS TIME AND WILL KEEP PCP OUT OF FORECAST
THROUGH THE REMAINDER OF THE WEEKEND. PLENTY OF BRIGHT JULY
SUNSHINE WILL DRIVE TEMPS UP NEAR NORMAL...CLOSE TO 90 BUT SFC
DEWPOINT TEMPS WILL BE RUNNING IN THE LOW TO MID 60S MOST PLACES
WHICH WILL MAKE FOR A MUCH MORE REFRESHING DAY THAN PREVIOUS ONES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 330 AM THURSDAY...CENTER OF HIGH PRESSURE NOSING DOWN FROM
THE NORTH WILL SHIFT OFF THE MID ATLANTIC COAST ALLOWING WINDS TO
COME AROUND TO A MORE ON SHORE NE TO E FLOW. WEAK HIGH PRESSURE
WILL CONTINUE TO REACH DOWN INTO THE CAROLINAS THROUGH MID WEEK AS
LEE SIDE TROUGH BECOMES MORE PRONOUNCED. RIDGING IN THE MID TO
UPPER LEVELS OVER THE MID WEST WILL BUILD EASTWARD OVER THE
WEEKEND...BUT AS IT BECOMES MORE AMPLIFIES UP THROUGH THE UPPER
MIDWEST BY TUES...A DEEPER NW FLOW ALOFT WILL ALLOW SOME CLOUDS
AND SHORTWAVE ENERGY TO SNEAK INTO AREA BUT RIDGE WILL BUILD BACK
EAST AND UP THE EAST COAST THROUGH MID WEEK AND THEREFORE MAY
INTRODUCE INCREASED CLOUDS AND SHWRS FOR TUES/WED TIME FRAME BUT
OVERALL SHWR ACTIVITY SHOULD REMAIN MORE ISOLATED HEADING INTO MID
WEEK AS RIDGE BUILDS BACK IN. THE ON SHORE FLOW DEVELOPING THROUGH
THE PERIOD WILL AID IN BRINGING DEWPOINT TEMPS BACK UP CLOSER TO
70 OR SO...HELPING TO INCREASE AFTN CU AND CHC OF SOME CONVECTIVE
DEVELOPMENT. TEMPS WILL BASICALLY REMAIN AROUND CLIMO.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
AS OF 18Z...TERMINALS ARE CURRENTLY VFR. CONVECTION HAS SO FAR
STAYED TO THE NORTH. A WEAK FRONT IS LOCATED FROM NEAR KLBT
TO KILM. THUNDERSTORMS ARE A SURE BET THIS AFTERNOON ALONG AND
EAST OF THE FRONT WITH HIGHEST CONFIDENCE OF OCCURRENCE AT KILM
AND TO A LESSER EFFECT KLBT. STORMS SHOULD PRODUCE SUFFICIENT
OUTFLOWS TO ALLOW DEVELOPMENT TO THE S-SW TOWARDS KFLO AND MORE
LIKELY KCRE/KMYR AS THE AFTERNOON PROGRESSES.
SHOWER POTENTIAL WILL PERSIST INTO THE EVENING HOURS. WINDS
BECOME LIGHT AND VARIABLE OR LIGHT NW LATE AFTERNOON AND EVENING.
THERE IS A FOG POTENTIAL MAINLY KFLO/KLBT OVERNIGHT WITH LOW TO
MODERATE POTENTIAL FOR IFR. VFR SHORTLY AFTER SUNRISE WITH N WINDS.
EXTENDED OUTLOOK...BRIEF MVFR POSSIBLE THROUGH THE PERIOD FROM
ISOLATED CONVECTION. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 110 PM THURSDAY...UPDATED FORECAST WITH ISSUANCE OF A
SEVERE THUNDERSTORM WATCH FOR THE ENTIRE AREA...GOOD UNTIL 8 PM.
PREVIOUS DISCUSSIONS FOLLOW:
LATEST OBS SHOW 2 FT SEAS WITH SSE WINDS OF 10 TO 15 KTS.
FORECAST ON TRACK WITH NO CHANGES NEEDED. PREVIOUS DISCUSSION
FOLLOWS:
LOW PRESSURE CENTERED OVER THE SOUTH CAROLINA SANDHILLS WILL MOVE
EASTWARD TODAY ALONG A WEAK STATIONARY FRONT. THIS FRONT CURRENTLY
SITS JUST NORTH OF CAPE FEAR AND IS OUTLINED BY A SHIFT IN WIND
DIRECTIONS FROM SOUTHERLY ALONG THE SC COAST TO SOUTHEASTERLY FROM
WRIGHTSVILLE BEACH AND SURF CITY TO THE OUTER BANKS.
AS INLAND AREAS HEAT UP QUICKLY THIS MORNING ATMOSPHERIC
CONDITIONS ARE STRONGLY SUPPORTIVE OF A LARGE CLUSTER OF
THUNDERSTORMS DEVELOPING ACROSS SOUTHERN NORTH CAROLINA...DROPPING
SOUTHEASTWARD AND AFFECTING THE COASTAL WATERS DURING THE
AFTERNOON. THESE STORMS WILL LIKELY CONTAIN LARGE AMOUNTS OF
LIGHTNING AND SUBSTANTIAL VISIBILITY RESTRICTIONS IN HEAVY RAIN.
SEVERAL OF THE HIGH- RESOLUTION MODELS INDICATE THE POTENTIAL FOR
A STRONG GUST FRONT AT THE LEADING EDGE OF THE STORMS WHICH MAY
PROMPT SPECIAL MARINE WARNINGS THIS AFTERNOON. MARINERS IN THE
CAPE FEAR AREA SHOULD EXPECT THE LARGEST IMPACT FROM THESE STORMS
BETWEEN 1-3 PM...WITH THE GRAND STAND AND GEORGETOWN AREAS A
COUPLE HOURS LATER.
LATE TONIGHT AS THE LOW SHIFTS EASTWARD ALONG THE FRONT AND
ENTERS THE ATLANTIC OCEAN SURFACE WINDS WILL SHIFT NORTHWESTERLY
AND MAY INCREASE TO 10-15 KT LATE. OUTSIDE OF THUNDERSTORMS SEAS
SHOULD AVERAGE 2 FEET TODAY...AND 2-3 FEET TONIGHT.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LOW PRESSURE ALONG LINGERING BOUNDARY
WILL SLIP FARTHER SOUTH THROUGH THE DAY ON FRIDAY. NORTHEAST FLOW
WILL DEVELOP BEHIND THIS BOUNDARY AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTH THROUGH THE WEEKEND. EXPECT WINDS TO REMAIN BELOW
15 KTS ACROSS MOST OF THE WATERS...BUT THERE SHOULD BE SOME
PERIODS OF HIGHER WAVES...UP CLOSER TO 20 KTS. THE WINDS WILL
BEGIN TO VEER AROUND FROM THE NE TO E. THE PERSISTENT STRONGER NE
TO E ON SHORE FLOW WILL PRODUCE SEAS UP TO 3 TO 5 FT...ESPECIALLY
THROUGH SAT NIGHT.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 330 AM...HIGH PRESSURE EXTENDING DOWN INTO THE CAROLINAS
FROM THE NORTHEAST WILL MOVE FARTHER EAST THROUGH THE
PERIOD...ALLOWING WINDS TO LIGHTEN AND VEER TO THE EAST. THE WINDS
SHOULD DECREASE TO 10 KTS OR LESS MOST OF THE TIME...BUT SEA
BREEZE EACH AFTN WILL ACT TO ENHANCE OVERALL ON SHORE FLOW. EXPECT
SEAS TO BE COMING DOWN AS WINDS LIGHTEN HEADING THROUGH LATE
SUNDAY INTO MONDAY. THEREFORE SEAS UP TO 3 TO 5 FT EARLY SUNDAY
SHOULD DROP TO 2 TO 4 FT SUN NIGHT. AS SHORTER PERIOD WINDWAVE
DIMINISHES THROUGH MONDAY AND WNA CONTINUES TO SHOW A LONGER
PERIOD UP TO 11 SEC WAVE MIXING IN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RGZ
NEAR TERM...REK/TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MRR
MARINE...REK/TRA/RGZ
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1235 PM EDT THU JUL 23 2015
.SYNOPSIS...A WAVE OF LOW PRESSURE DEVELOPING ALONG A STALLED
FRONTAL ZONE IN UPSTATE SOUTH CAROLINA WILL TRACK SLOWLY EAST TOWARD
THE CAROLINA COAST THIS AFTERNOON INTO TONIGHT...THEN STALL OFFSHORE
THE SOUTHEAST COAST OVER THE WEEKEND AS WEAK HIGH PRESSURE EXTENDS
INTO THE REGION FROM THE NORTH.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 930 AM THURSDAY...
FORECAST LARGELY ON TRACK WITH SMALL SPATIAL/TEMPORAL MODIFICATIONS.
SEVERAL CLUSTERS OF SHOWERS/STORMS ARE PROGRESSING ESE OVER THE FAR
NRN AND NE CWA... WITHIN A BAND OF ENHANCE LOW LEVEL MOISTURE
CONVERGENCE ALONG A TIGHT THETA-E GRADIENT. PW VALUES OVER CENTRAL
NC HAVE SURGED WELL BACK UP ABOVE NORMAL IN THE LAST 12 HRS...
FACILITATING A VOLATILE ATMOSPHERE WITH SCATTERED TO NUMEROUS
SHOWERS AND STORMS FUELED BY WEAK TO MODERATE INSTABILITY...
IMPROVING DYNAMIC FORCING FOR ASCENT AS A MID LEVEL WAVE TRACKS FROM
TN ACROSS THE CAROLINAS TODAY... AND IMPROVING KINEMATICS AS WELL-
DEFINED SURFACE LOW PRESSURE PERSISTS ALONG THE FRONTAL ZONE OVER
NRN SC. THE LATEST HRRR RUNS AND THE NSSL WRF HAVE DONE A GOOD JOB
WITH CONVECTION SO FAR THIS MORNING... AND BOTH SHIFT THE GREATER
STORM COVERAGE (50-60%) FROM THE NE CWA TO THE SOUTHEAST THIS
AFTERNOON... WHERE LOW LEVEL MASS CONVERGENCE ENE OF THE LOW WILL BE
HIGHEST WITH THE BETTER POTENTIAL FOR INSTABILITY. WILL RETAIN A
TREND TO LIKELY POPS IN THIS AREA. EFFECTIVE DEEP LAYER SHEAR
REMAINS MARGINAL AT 20-30 KTS BUT STILL ENOUGH FOR A THREAT OF
ISOLATED STRONG TO DAMAGING WIND GUSTS WITH ANY CELLS. MODELS THEN
REDEVELOP SHOWERS AND ISOLATED STORMS BACK OVER THE SW CWA THIS
EVENING... AS THE MID LEVEL WAVE MOVES IN... IN CONJUNCTION WITH
FORMATION OF A NEW LEE LOW OVER UPSTATE SC. WILL KEEP THE TREND BACK
TOWARD HIGH POPS THIS EVENING IN OUR SW... SPREADING EAST
OVERNIGHT... ALTHOUGH WILL RE-EVALUATE POTENTIAL COVERAGE THIS
AFTERNOON. THE CLOUDS/PRECIP AND LIGHT NE FLOW ARE BOUND TO HOLD
TEMPS DOWN BELOW NORMAL TODAY IN THE NE. EXPECT HIGHS FROM THE LOW
80S N TO NEAR 90 SOUTH... PREDICATED ON GETTING AT LEAST SOME
ISOLATION NORTH THIS AFTERNOON BEHIND THE ONGOING CONVECTION. -GIH
PREVIOUS DISCUSSION FROM 400 AM... OVERVIEW: DIFFICULT FORECAST. 06Z
SPC MESOANALYSIS AND REMOTE SENSING DATA INDICATED NUMEROUS SMALL
AMPLITUDE WAVES TRACKING EAST/ESE ALONG THE SOUTHERN FRINGE OF THE
WESTERLIES THROUGH THE TN VALLEY THIS MORNING...DOWNSTREAM OF A
PRONOUNCED UPPER LEVEL RIDGE ANCHORED OVER THE LOWER MIDWEST. IN
RESPONSE TO DPVA ATTENDANT AN APPROACHING DISTURBANCE...A WEAK
SURFACE LOW IS DEVELOPING ALONG A STALLED FRONTAL ZONE SITUATED
ACROSS UPSTATE SC/SOUTHWEST NC (NEAR SHELBY NC) AND WEAK WARM
ADVECTION HAS COMMENCED OVER CENTRAL NC AS 925-850 MB FLOW BACKS IN
ADVANCE OF THE WAVE. WITH ADDITIONAL SMALL AMPLITUDE WAVES PRESENT
UPSTREAM AND A WIDE VARIETY OF MECHANISMS (CONVECTION /LATENT HEAT
RELEASE/ IN PARTICULAR) THAT CAN AFFECT THE EVOLUTION OF LOW-LEVEL
HEIGHT/WIND/MOISTURE FIELDS...CONFIDENCE REMAINS LOW WITH REGARD TO
CONVECTIVE COVERAGE/TIMING TODAY INTO TONIGHT. QUALITATIVELY...GIVEN
THE PATTERN ONE WOULD EXPECT INCREASED CLOUD COVER...CHANCES FOR
CONVECTION...AND AT OR BELOW NORMAL TEMPERATURES.
CONVECTION: IN RESPONSE TO WEAK LOW-LEVEL CONVERGENCE...WARM
ADVECTION... APPROACHING DPVA... AND NOCTURNAL DESTABILIZATION
(DRIVEN BY LOW-LEVEL MOISTURE ADVECTION)...ISOLATED ELEVATED
CONVECTION HAS ALREADY DEVELOPED IN VICINITY OF HWY 64. THE LATEST
RAP GUIDANCE SUGGESTS ELEVATED CONVECTION WILL INCREASE IN COVERAGE
AND INTENSITY ALONG/NORTH OF HWY 64 THROUGH 15Z AS THE EASTERN-MOST
UPPER LEVEL DISTURBANCE APPROACHES...LOW-LEVEL CONVERGENCE
STRENGTHENS /FLOW BACKS/...AND MOISTURE ADVECTION AIDS IN FURTHER
DESTABILIZATION. AS THE LEAD DISTURBANCE PROGRESSES EAST ACROSS
CENTRAL NC BY EARLY AFTERNOON...THE DEVELOPING SFC-H925 LOW IS
EXPECTED TO WEAKEN/BROADEN OVER WESTERN NC...WITH AN ATTENDANT
WEAKENING OF WARM ADVECTION AS LOW-LEVEL FLOW VEERS TO THE SOUTH AND
WEAKENS ACROSS CENTRAL NC. HOWEVER...WEAK LOW-LEVEL CONVERGENCE AND
DIURNAL DESTABILIZATION WITHIN THE WARM SECTOR SHOULD BE SUFFICIENT
FOR ANY ONGOING CONVECTION TO PERSIST DURING THE EARLY/MID
AFTERNOON...MOST LIKELY IN THE FORM OF SFC-BASED CONVECTION
PROPAGATING SOUTHEAST (ALONG OUTFLOW) THROUGH THE COASTAL PLAIN INTO
EASTERN/COASTAL NC DURING THE AFTERNOON.
SEVERE: THOUGH SFC-BASED CONVECTION WILL BECOME INCREASINGLY LIKELY
ALONG/SOUTH OF HWY 64 AS THE WARM SECTOR SLOWLY ADVANCES FROM CAPE
FEAR INTO THE SANDHILLS 08-12Z...CONVECTION SHOULD REMAIN ELEVATED
IN NATURE NORTH OF THE I-85 CORRIDOR. BY OR SHORTLY AFTER SUNRISE...
MARGINAL TO MODERATE INSTABILITY AND DEEP LAYER SHEAR ~30 KT WILL
CONTRIBUTE TO SUPERCELL COMPOSITE PARAMETER VALUES AS HIGH AS 1-3
(PRIMARILY SOUTH AND EAST OF THE TRIANGLE)...INDICATING THAT THE
ENVIRONMENT WILL BE BASICALLY SUPPORTIVE OF SEVERE WEATHER DURING
THE MORNING...PRIMARILY IN THE FORM OF WET DOWNBURSTS VIA A
COMBINATION OF MOMENTUM TRANSPORT (20-25 KT MID-LEVEL FLOW) AND
PRECIP LOADING...PARTICULARLY WITH PWAT VALUES AS HIGH AS 2.00-
2.25". WEAK LOW-LEVEL SPEED SHEAR ON THE EASTERN PERIPHERY OF THE
SFC LOW SHOULD EFFECTIVELY LIMIT 0-1 KM SRH VALUES TO NO HIGHER THAN
50-100 M2/S2 IN CENTRAL NC THIS MORNING...THOUGH VALUES AS HIGH AS
150-200 M2/S2 WILL BE POSSIBLE THIS AFTERNOON IN COASTAL NC...
PERHAPS INCLUDING PORTIONS OF THE SE COASTAL PLAIN. WITH THIS IN
MIND...AN ISOLATED TOR (BRIEF/LOW-END VARIETY)...CANNOT BE RULED OUT
WITH VIGOROUS UPDRAFTS (IF ANY) THIS AFTERNOON...PRIMARILY FAR SE
COASTAL PLAIN (I.E. SAMPSON/WAYNE/CUMBERLAND). -VINCENT
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 311 AM THURSDAY...
THE WEAK MID/UPPER LOW WILL SLOWLY DRIFT DEEP INTO THE SE STATES
FRIDAY. MOST IF NOT ALL THE SCATTERED SHOWERS AND THUNDERSTORMS
SHOULD BE IN OUR SE COUNTIES EARLY IN THE DAY... BEFORE SHIFTING ON
SOUTHWARD AND REDEVELOPING WITH DIURNAL HEATING AGAIN FRIDAY
AFTERNOON. OTHERWISE... PARTLY SUNNY WITH HIGHS IN THE MID TO UPPER
80S. PARTLY CLOUDY TO MOSTLY CLEAR SKIES EXPECTED FRIDAY NIGHT WITH
LOWS IN THE MID TO UPPER 60S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 1255 AM THURSDAY...
DRY WEATHER IS STILL ANTICIPATED GIVEN THE FLOW PATTERN OVER THE
REGION SATURDAY AND SUNDAY. IT APPEARS THAT THERE WILL BE A SLOWLY
INCREASING CHANCE OF MAINLY DIURNAL SHOWERS AND THUNDERSTORMS MONDAY
THROUGH WEDNESDAY. HOWEVER... THERE CONTINUES TO BE SOME MODEL
SPREAD IN WHEN THE MOISTURE/INSTABILITY WILL INCREASE ENOUGH FOR
THIS TO OCCUR. WE WILL CONTINUE THE CURRENT LOW CHANCE POP FOR PM
THUNDERSTORMS MONDAY THROUGH WEDNESDAY. TEMPERATURES SHOULD BE NEAR
THE 30 YEAR AVERAGES FOR LATE JULY THIS WEEKEND... AND ONLY SLOWLY
RISE TO ABOVE NORMAL BY TUE-WED.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1235 PM THURSDAY...
OF MOST IMMEDIATE AVIATION CONCERN IS THE HIGH PROBABILITY OF
BRIEFLY VERY POOR (LIFR) CONDITIONS (LOW CIGS AND VSBYS WITH
TORRENTIAL RAIN AND GUSTY WINDS WITH ISOLATED WET MICROBURSTS
POSSIBLE) IN AND NEAR STORMS IN THE NEXT HOUR OR TWO... MOST LIKELY
TO AFFECT RWI/FAY THROUGH THIS AFTERNOON. SUCH CONDITIONS RECENTLY
IMPACTED RDU... HOWEVER RDU SHOULD SEE A RELATIVE LULL IN STORMS
THROUGH THE AFTERNOON... WITH PERHAPS SOME SHOWERS AFTER NIGHTFALL.
OTHERWISE... MVFR TO IFR CIGS OVER MUCH OF CENTRAL NC (ALL BUT FAY)
WILL SLOWLY LIFT BUT ARE LIKELY TO REMAIN SUB-VFR AT INT/GSO/RDU
THROUGH MID AFTERNOON... THEN INCHING UP INTO LOW-END VFR CIGS AFTER
20Z... ALTHOUGH SCT-BKN MVFR CLOUDS MAY LINGER AT RDU AND PERHAPS
GSO. FAY IS LIKELY TO BE ADVERSELY IMPACTED BY CLUSTERS OF SUB-VFR
SHOWERS AND STORMS FOR THE MAJORITY OF THE 18Z-02Z PERIOD. AFTER
02Z... IFR STRATUS/FOG IS LIKELY AT RDU/FAY/RWI THROUGH THE
OVERNIGHT... WITH A MUCH LOWER CHANCE AT INT/GSO. SCATTERED SHOWERS
MAY AFFECT INTO/GSO/FAY OVERNIGHT... WITH A MUCH LOWER CHANCE AT
RDU/RWI. AFTER 14Z... ANY SUB-VFR CONDITIONS ARE EXPECTED TO IMPROVE
TO VFR AREAWIDE... AS HIGH PRESSURE NOSES IN FROM THE NORTH.
LOOKING BEYOND 18Z FRI... VFR CONDITIONS SHOULD DOMINATE AT ALL
CENTRAL NC TERMINALS AS HIGH PRESSURE CONTINUES TO BUILD IN FROM THE
NORTH AND NE THROUGH THE WEEKEND. STORM CHANCES RETURN LATE MON AND
ESPECIALLY MON NIGHT INTO TUE AS A DISTURBANCE DROPS IN FROM THE
NORTHWEST. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...PWB
LONG TERM...PWB
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1029 AM EDT THU JUL 23 2015
.SYNOPSIS...
LOW PRESSURE OVER NORTHERN SOUTH CAROLINA WILL MOVE EAST ALONG A
STALLED FRONT TODAY AND OFF THE COAST TONIGHT. THIS LOW WILL PUSH
THE FRONT INTO GEORGIA FOR THIS WEEKEND. HIGH PRESSURE WILL BUILD
DOWN FROM THE NORTH...WITH A DRYING TREND EXPECTED THIS WEEKEND
INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM THURSDAY...ANALYSIS OF MORNING SOUNDINGS AND LATEST
GUIDANCE CONFIRM EARLIER FORECAST OF AN ACTIVE WEATHER
DAY...ESPECIALLY THIS AFTERNOON AND EVENING...WITH THE PRIMARY
THREATS BEING HEAVY RAIN AND UNUSUALLY FREQUENT LIGHTNING.
DAMAGING WIND GUSTS ARE ALSO A POSSIBILITY. NO CHANGES NEEDED YET
TO THE FORECAST. PREVIOUS DISCUSSION FOLLOWS:
LOW PRESSURE CENTERED OVER THE SC SANDHILLS WILL MOVE EASTWARD
ALONG A STATIONARY FRONT TODAY...EXITING INTO THE ATLANTIC OCEAN
TONIGHT. MODELS ARE ALMOST UNANIMOUS IN THEIR DEPICTION OF A LARGE
CLUSTER OF THUNDERSTORMS DEVELOPING WITHIN A REGION OF LOW-LEVEL
CONVERGENCE AND LARGE INSTABILITY OVER SOUTHERN NORTH CAROLINA
JUST NORTH OF THE STATIONARY FRONT LATE THIS MORNING. SURFACE CAPE
IS PREDICTED TO GROW AS LARGE AS 3000 J/KG WITH LIFTED INDICES TO
-6. 700 MB WINDS INCREASING TO 25 KT SHOULD INCREASE BULK SHEAR
VALUES JUST ENOUGH TO PRODUCE ORGANIZED MULTICELLULAR STORMS
TODAY...WITH COLD POOL EFFECTS LIKELY PUSHING THE CLUSTER
SOUTHEASTWARD ACROSS THE CAPE FEAR AREA EARLY THIS AFTERNOON AND
INTO NORTHEASTERLY SOUTH CAROLINA BY MID TO LATE AFTERNOON.
IMPACTS FROM THESE STORMS COULD BE CONSIDERABLE. COMPUTED
EQUILIBRIUM PARCEL HEIGHTS NEAR 50000 FT AND LOTS OF INSTABILITY
ABOVE THE -20C LEVEL INDICATES THESE STORMS COULD BE ENORMOUS
LIGHTNING PRODUCERS WITH PLENTY OF ICE/GRAUPEL GENERATION ALOFT.
ALTHOUGH NO DRY LAYERS ARE EVIDENT IN FORECAST SOUNDINGS
PRECIPITATION LOADING RESULTING FROM SUCH VIGOROUS CONVECTION
SHOULD PRODUCE GUSTY WINDS...PARTICULARLY AS THE STORMS ARE SHOWN
IN THE HIGH RESOLUTION WRF-NMM...WRF-ARW...AND HRRR MODELS TO FORM
A LARGE MASSED OUTFLOW PUSHING SOUTHEASTWARD TO THE COAST. WITH
THE SYNOPTIC FRONT STALLED ACROSS THE AREA AND ANTICIPATED
BOUNDARY COLLISIONS THE STORMS SHOULD ALSO BE HEAVY RAIN MAKERS
WITH LOCALIZED FLOODING POSSIBLE. FORECAST RAIN CHANCES HAVE BEEN
INCREASED TO 80 PERCENT ACROSS SE NORTH CAROLINA...FOCUSED ON THE
NOON-4 PM TIMEFRAME.
CONVECTION SHOULD TAKE SEVERAL ADDITIONAL HOURS TO PROPAGATE
SOUTHWARD AND AFFECT NE SOUTH CAROLINA WHICH WILL BE LOCATED SOUTH
OF THE STATIONARY FRONT. THIS MEANS SEVERAL ADDITIONAL HOURS OF
HOT SUNSHINE...AND TEMPERATURES HERE WILL RISE INTO THE MID TO
UPPER 90S. FORECAST HEAT INDICES ARE JUST BELOW 105-DEGREE HEAT
ADVISORY CRITERIA ACROSS GEORGETOWN...WILLIAMSBURG AND SOUTHERN
FLORENCE COUNTIES.
AN UPPER LEVEL DISTURBANCE CURRENTLY PRODUCING THUNDERSTORMS OVER
CENTRAL TENNESSEE WILL REACH THE EASTERN CAROLINAS THIS EVENING.
THIS COULD HELP CONVECTIVE ACTIVITY TO PERSIST INTO THE EVENING
HOURS EVEN AFTER THE ATMOSPHERE PRETTY MUCH OVERTURNS DURING THE
AFTERNOON. THE LOW WILL SCOOT EASTWARD ALONG THE FRONT OFFSHORE
AFTER MIDNIGHT WITH SURFACE WINDS TURNING NORTHWESTERLY...QUITE AN
ODD DIRECTION FOR THE CAROLINAS IN THE MIDDLE OF SUMMER. THIS IS
THE THIRD COLD FRONTAL PASSAGE OF JULY!
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LATEST MODELS SHOW LOW JUST OFF THE CAPE
FEAR COAST FRI MORNING. EXPECT BEST CONVECTION OVER THE COASTAL
WATERS WITH MOST AREAS SEEING A DEEP FLOW OF DRIER AIR ADVECTING
IN FROM THE NORTH. MID TO UPPER TROUGH WILL PUSH LOW PRESSURE
ALONG LINGERING BOUNDARY SOUTH AND EAST OF AREA THROUGH THE
DAY...BUT PLENTY OF RESIDUAL LOW LEVEL MOISTURE FROM PREVIOUS DAYS
CONVECTION WILL SLOW CLEARING AND COMBINE WITH CONVERGENCE
ASSOCIATED WITH LOW AND OTHER LOCALIZED BOUNDARIES SUCH AS THE SEA
BREEZE TO PRODUCE SOME SHWRS/TSTMS. LOOKS LIKE BEST CHC WILL MOVE
SOUTH THROUGH THE DAY AS HIGH PRESSURE BEGINS TO BUILD DOWN FROM
THE NORTH BUT MAY NOT BE FAST ENOUGH TO ELIMINATE POPS FROM
FORECAST. NAM SHOWS MAIN FOCUS OF CONVECTION ALONG COASTAL SOUTH
CAROLINA WHERE BEST CONVERGENCE SHOULD BE AS WE DEVELOP A N-NE
FLOW. MAY SEE ENOUGH SUBSIDENCE AND DRY AIR THROUGH THE MID TO
UPPER LEVELS BY LATE FRI TO ALLOW FOR ONLY A DECENT STRATOCU FIELD
OVER NC. PCP WATER VALUES OVER 2 INCHES EARLY FRI MORNING WILL
DROP DOWN CLOSE TO AN INCH BY SAT MORNING. LINGERING CLOUDS AND
PCP WILL KEEP TEMPS IN THE 80S MOST OF THE DAY BUT PLACES THAT SEE
SOME SUN MAKE AN APPEARANCE WILL REACH CLOSE TO 90.
BY LATE FRI INTO FRI NIGHT...PLENTY OF DRY AIR AND SUBSIDENCE
THROUGH THE MID TO UPPER LEVELS WILL REACH DOWN OVER THE FORECAST
AREA AS DRY HIGH PRESSURE AT THE SFC NOSES DOWN FROM THE NORTH.
WILL SHOW CLEARING AT THIS TIME AND WILL KEEP PCP OUT OF FORECAST
THROUGH THE REMAINDER OF THE WEEKEND. PLENTY OF BRIGHT JULY
SUNSHINE WILL DRIVE TEMPS UP NEAR NORMAL...CLOSE TO 90 BUT SFC
DEWPOINT TEMPS WILL BE RUNNING IN THE LOW TO MID 60S MOST PLACES
WHICH WILL MAKE FOR A MUCH MORE REFRESHING DAY THAN PREVIOUS ONES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 330 AM THURSDAY...CENTER OF HIGH PRESSURE NOSING DOWN FROM
THE NORTH WILL SHIFT OFF THE MID ATLANTIC COAST ALLOWING WINDS TO
COME AROUND TO A MORE ON SHORE NE TO E FLOW. WEAK HIGH PRESSURE
WILL CONTINUE TO REACH DOWN INTO THE CAROLINAS THROUGH MID WEEK AS
LEE SIDE TROUGH BECOMES MORE PRONOUNCED. RIDGING IN THE MID TO
UPPER LEVELS OVER THE MID WEST WILL BUILD EASTWARD OVER THE
WEEKEND...BUT AS IT BECOMES MORE AMPLIFIES UP THROUGH THE UPPER
MIDWEST BY TUES...A DEEPER NW FLOW ALOFT WILL ALLOW SOME CLOUDS
AND SHORTWAVE ENERGY TO SNEAK INTO AREA BUT RIDGE WILL BUILD BACK
EAST AND UP THE EAST COAST THROUGH MID WEEK AND THEREFORE MAY
INTRODUCE INCREASED CLOUDS AND SHWRS FOR TUES/WED TIME FRAME BUT
OVERALL SHWR ACTIVITY SHOULD REMAIN MORE ISOLATED HEADING INTO MID
WEEK AS RIDGE BUILDS BACK IN. THE ON SHORE FLOW DEVELOPING THROUGH
THE PERIOD WILL AID IN BRINGING DEWPOINT TEMPS BACK UP CLOSER TO
70 OR SO...HELPING TO INCREASE AFTN CU AND CHC OF SOME CONVECTIVE
DEVELOPMENT. TEMPS WILL BASICALLY REMAIN AROUND CLIMO.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
AS OF 12Z...TERMINALS ARE CURRENTLY VFR ALTHOUGH SOME MVFR VSBYS
IN BR COULD OCCUR MAINLY AT KLBT UNTIL 13Z. A WEAK FRONT IS
LOCATED FROM NEAR KFLO TO KMYR. WINDS THIS MORNING WILL BE ESE-SE
AT KILM/KLBT WITH S-SW WINDS ELSEWHERE. THUNDERSTORMS ARE A SURE
BET TODAY AND WILL EVENTUALLY AFFECT EVERY TERMINAL. CONFIDENCE IN
EXACT TIMING IS LOW BUT KLBT SHOULD BE INITIALLY AFFECTED BY LATE
MORNING THEN KILM/KFLO TOWARDS EARLY AFTERNOON. KCRE/KMYR SHOULD
BE AFFECTED MOSTLY IN THE AFTERNOON. TEMPO IFR WITH WIND GUSTS TO
35 KT POSSIBLE WITH THE STORMS.
THUNDERSTORMS SHOULD END IN THE 21-00Z TIME FRAME WITH VFR
LIKELY... BUT SHOWERS WILL POTENTIAL PERSIST INTO THE EVENING
HOURS. WINDS BECOME LIGHT AND VARIABLE OR LIGHT NW LATE AFTERNOON
AND EVENING. THERE IS A FOG POTENTIAL MAINLY KFLO/KLBT OVERNIGHT
WITH LOW TO MODERATE POTENTIAL FOR IFR.
EXTENDED OUTLOOK...BRIEF MVFR POSSIBLE THROUGH THE PERIOD FROM
ISOLATED CONVECTION. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM THURSDAY...LATEST OBS SHOW 2 FT SEAS WITH SSE WINDS
OF 10 TO 15 KTS. FORECAST ON TRACK WITH NO CHANGES NEEDED.
PREVIOUS DISCUSSION FOLLOWS:
LOW PRESSURE CENTERED OVER THE SOUTH CAROLINA SANDHILLS WILL MOVE
EASTWARD TODAY ALONG A WEAK STATIONARY FRONT. THIS FRONT CURRENTLY
SITS JUST NORTH OF CAPE FEAR AND IS OUTLINED BY A SHIFT IN WIND
DIRECTIONS FROM SOUTHERLY ALONG THE SC COAST TO SOUTHEASTERLY FROM
WRIGHTSVILLE BEACH AND SURF CITY TO THE OUTER BANKS.
AS INLAND AREAS HEAT UP QUICKLY THIS MORNING ATMOSPHERIC
CONDITIONS ARE STRONGLY SUPPORTIVE OF A LARGE CLUSTER OF
THUNDERSTORMS DEVELOPING ACROSS SOUTHERN NORTH CAROLINA...DROPPING
SOUTHEASTWARD AND AFFECTING THE COASTAL WATERS DURING THE
AFTERNOON. THESE STORMS WILL LIKELY CONTAIN LARGE AMOUNTS OF
LIGHTNING AND SUBSTANTIAL VISIBILITY RESTRICTIONS IN HEAVY RAIN.
SEVERAL OF THE HIGH- RESOLUTION MODELS INDICATE THE POTENTIAL FOR
A STRONG GUST FRONT AT THE LEADING EDGE OF THE STORMS WHICH MAY
PROMPT SPECIAL MARINE WARNINGS THIS AFTERNOON. MARINERS IN THE
CAPE FEAR AREA SHOULD EXPECT THE LARGEST IMPACT FROM THESE STORMS
BETWEEN 1-3 PM...WITH THE GRAND STAND AND GEORGETOWN AREAS A
COUPLE HOURS LATER.
LATE TONIGHT AS THE LOW SHIFTS EASTWARD ALONG THE FRONT AND
ENTERS THE ATLANTIC OCEAN SURFACE WINDS WILL SHIFT NORTHWESTERLY
AND MAY INCREASE TO 10-15 KT LATE. OUTSIDE OF THUNDERSTORMS SEAS
SHOULD AVERAGE 2 FEET TODAY...AND 2-3 FEET TONIGHT.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LOW PRESSURE ALONG LINGERING BOUNDARY
WILL SLIP FARTHER SOUTH THROUGH THE DAY ON FRIDAY. NORTHEAST FLOW
WILL DEVELOP BEHIND THIS BOUNDARY AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTH THROUGH THE WEEKEND. EXPECT WINDS TO REMAIN BELOW
15 KTS ACROSS MOST OF THE WATERS...BUT THERE SHOULD BE SOME
PERIODS OF HIGHER WAVES...UP CLOSER TO 20 KTS. THE WINDS WILL
BEGIN TO VEER AROUND FROM THE NE TO E. THE PERSISTENT STRONGER NE
TO E ON SHORE FLOW WILL PRODUCE SEAS UP TO 3 TO 5 FT...ESPECIALLY
THROUGH SAT NIGHT.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 330 AM...HIGH PRESSURE EXTENDING DOWN INTO THE CAROLINAS
FROM THE NORTHEAST WILL MOVE FARTHER EAST THROUGH THE
PERIOD...ALLOWING WINDS TO LIGHTEN AND VEER TO THE EAST. THE WINDS
SHOULD DECREASE TO 10 KTS OR LESS MOST OF THE TIME...BUT SEA
BREEZE EACH AFTN WILL ACT TO ENHANCE OVERALL ON SHORE FLOW. EXPECT
SEAS TO BE COMING DOWN AS WINDS LIGHTEN HEADING THROUGH LATE
SUNDAY INTO MONDAY. THEREFORE SEAS UP TO 3 TO 5 FT EARLY SUNDAY
SHOULD DROP TO 2 TO 4 FT SUN NIGHT. AS SHORTER PERIOD WINDWAVE
DIMINISHES THROUGH MONDAY AND WNA CONTINUES TO SHOW A LONGER
PERIOD UP TO 11 SEC WAVE MIXING IN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RGZ
NEAR TERM...REK/TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MRR
MARINE...REK/TRA/RGZ
AREA FORECAST DISCUSSION
NWS RALEIGH NC
930 AM EDT THU JUL 23 2015
.SYNOPSIS...A WAVE OF LOW PRESSURE DEVELOPING ALONG A STALLED
FRONTAL ZONE IN UPSTATE SOUTH CAROLINA WILL TRACK SLOWLY EAST TOWARD
THE CAROLINA COAST THIS AFTERNOON INTO TONIGHT...THEN STALL OFFSHORE
THE SOUTHEAST COAST OVER THE WEEKEND AS WEAK HIGH PRESSURE EXTENDS
INTO THE REGION FROM THE NORTH.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 930 AM THURSDAY...
FORECAST LARGELY ON TRACK WITH SMALL SPATIAL/TEMPORAL MODIFICATIONS.
SEVERAL CLUSTERS OF SHOWERS/STORMS ARE PROGRESSING ESE OVER THE FAR
NRN AND NE CWA... WITHIN A BAND OF ENHANCE LOW LEVEL MOISTURE
CONVERGENCE ALONG A TIGHT THETA-E GRADIENT. PW VALUES OVER CENTRAL
NC HAVE SURGED WELL BACK UP ABOVE NORMAL IN THE LAST 12 HRS...
FACILITATING A VOLATILE ATMOSPHERE WITH SCATTERED TO NUMEROUS
SHOWERS AND STORMS FUELED BY WEAK TO MODERATE INSTABILITY...
IMPROVING DYNAMIC FORCING FOR ASCENT AS A MID LEVEL WAVE TRACKS FROM
TN ACROSS THE CAROLINAS TODAY... AND IMPROVING KINEMATICS AS WELL-
DEFINED SURFACE LOW PRESSURE PERSISTS ALONG THE FRONTAL ZONE OVER
NRN SC. THE LATEST HRRR RUNS AND THE NSSL WRF HAVE DONE A GOOD JOB
WITH CONVECTION SO FAR THIS MORNING... AND BOTH SHIFT THE GREATER
STORM COVERAGE (50-60%) FROM THE NE CWA TO THE SOUTHEAST THIS
AFTERNOON... WHERE LOW LEVEL MASS CONVERGENCE ENE OF THE LOW WILL BE
HIGHEST WITH THE BETTER POTENTIAL FOR INSTABILITY. WILL RETAIN A
TREND TO LIKELY POPS IN THIS AREA. EFFECTIVE DEEP LAYER SHEAR
REMAINS MARGINAL AT 20-30 KTS BUT STILL ENOUGH FOR A THREAT OF
ISOLATED STRONG TO DAMAGING WIND GUSTS WITH ANY CELLS. MODELS THEN
REDEVELOP SHOWERS AND ISOLATED STORMS BACK OVER THE SW CWA THIS
EVENING... AS THE MID LEVEL WAVE MOVES IN... IN CONJUNCTION WITH
FORMATION OF A NEW LEE LOW OVER UPSTATE SC. WILL KEEP THE TREND BACK
TOWARD HIGH POPS THIS EVENING IN OUR SW... SPREADING EAST
OVERNIGHT... ALTHOUGH WILL RE-EVALUATE POTENTIAL COVERAGE THIS
AFTERNOON. THE CLOUDS/PRECIP AND LIGHT NE FLOW ARE BOUND TO HOLD
TEMPS DOWN BELOW NORMAL TODAY IN THE NE. EXPECT HIGHS FROM THE LOW
80S N TO NEAR 90 SOUTH... PREDICATED ON GETTING AT LEAST SOME
ISOLATION NORTH THIS AFTERNOON BEHIND THE ONGOING CONVECTION. -GIH
PREVIOUS DISCUSSION FROM 400 AM... OVERVIEW: DIFFICULT FORECAST. 06Z
SPC MESOANALYSIS AND REMOTE SENSING DATA INDICATED NUMEROUS SMALL
AMPLITUDE WAVES TRACKING EAST/ESE ALONG THE SOUTHERN FRINGE OF THE
WESTERLIES THROUGH THE TN VALLEY THIS MORNING...DOWNSTREAM OF A
PRONOUNCED UPPER LEVEL RIDGE ANCHORED OVER THE LOWER MIDWEST. IN
RESPONSE TO DPVA ATTENDANT AN APPROACHING DISTURBANCE...A WEAK
SURFACE LOW IS DEVELOPING ALONG A STALLED FRONTAL ZONE SITUATED
ACROSS UPSTATE SC/SOUTHWEST NC (NEAR SHELBY NC) AND WEAK WARM
ADVECTION HAS COMMENCED OVER CENTRAL NC AS 925-850 MB FLOW BACKS IN
ADVANCE OF THE WAVE. WITH ADDITIONAL SMALL AMPLITUDE WAVES PRESENT
UPSTREAM AND A WIDE VARIETY OF MECHANISMS (CONVECTION /LATENT HEAT
RELEASE/ IN PARTICULAR) THAT CAN AFFECT THE EVOLUTION OF LOW-LEVEL
HEIGHT/WIND/MOISTURE FIELDS...CONFIDENCE REMAINS LOW WITH REGARD TO
CONVECTIVE COVERAGE/TIMING TODAY INTO TONIGHT. QUALITATIVELY...GIVEN
THE PATTERN ONE WOULD EXPECT INCREASED CLOUD COVER...CHANCES FOR
CONVECTION...AND AT OR BELOW NORMAL TEMPERATURES.
CONVECTION: IN RESPONSE TO WEAK LOW-LEVEL CONVERGENCE...WARM
ADVECTION... APPROACHING DPVA... AND NOCTURNAL DESTABILIZATION
(DRIVEN BY LOW-LEVEL MOISTURE ADVECTION)...ISOLATED ELEVATED
CONVECTION HAS ALREADY DEVELOPED IN VICINITY OF HWY 64. THE LATEST
RAP GUIDANCE SUGGESTS ELEVATED CONVECTION WILL INCREASE IN COVERAGE
AND INTENSITY ALONG/NORTH OF HWY 64 THROUGH 15Z AS THE EASTERN-MOST
UPPER LEVEL DISTURBANCE APPROACHES...LOW-LEVEL CONVERGENCE
STRENGTHENS /FLOW BACKS/...AND MOISTURE ADVECTION AIDS IN FURTHER
DESTABILIZATION. AS THE LEAD DISTURBANCE PROGRESSES EAST ACROSS
CENTRAL NC BY EARLY AFTERNOON...THE DEVELOPING SFC-H925 LOW IS
EXPECTED TO WEAKEN/BROADEN OVER WESTERN NC...WITH AN ATTENDANT
WEAKENING OF WARM ADVECTION AS LOW-LEVEL FLOW VEERS TO THE SOUTH AND
WEAKENS ACROSS CENTRAL NC. HOWEVER...WEAK LOW-LEVEL CONVERGENCE AND
DIURNAL DESTABILIZATION WITHIN THE WARM SECTOR SHOULD BE SUFFICIENT
FOR ANY ONGOING CONVECTION TO PERSIST DURING THE EARLY/MID
AFTERNOON...MOST LIKELY IN THE FORM OF SFC-BASED CONVECTION
PROPAGATING SOUTHEAST (ALONG OUTFLOW) THROUGH THE COASTAL PLAIN INTO
EASTERN/COASTAL NC DURING THE AFTERNOON.
SEVERE: THOUGH SFC-BASED CONVECTION WILL BECOME INCREASINGLY LIKELY
ALONG/SOUTH OF HWY 64 AS THE WARM SECTOR SLOWLY ADVANCES FROM CAPE
FEAR INTO THE SANDHILLS 08-12Z...CONVECTION SHOULD REMAIN ELEVATED
IN NATURE NORTH OF THE I-85 CORRIDOR. BY OR SHORTLY AFTER SUNRISE...
MARGINAL TO MODERATE INSTABILITY AND DEEP LAYER SHEAR ~30 KT WILL
CONTRIBUTE TO SUPERCELL COMPOSITE PARAMETER VALUES AS HIGH AS 1-3
(PRIMARILY SOUTH AND EAST OF THE TRIANGLE)...INDICATING THAT THE
ENVIRONMENT WILL BE BASICALLY SUPPORTIVE OF SEVERE WEATHER DURING
THE MORNING...PRIMARILY IN THE FORM OF WET DOWNBURSTS VIA A
COMBINATION OF MOMENTUM TRANSPORT (20-25 KT MID-LEVEL FLOW) AND
PRECIP LOADING...PARTICULARLY WITH PWAT VALUES AS HIGH AS 2.00-
2.25". WEAK LOW-LEVEL SPEED SHEAR ON THE EASTERN PERIPHERY OF THE
SFC LOW SHOULD EFFECTIVELY LIMIT 0-1 KM SRH VALUES TO NO HIGHER THAN
50-100 M2/S2 IN CENTRAL NC THIS MORNING...THOUGH VALUES AS HIGH AS
150-200 M2/S2 WILL BE POSSIBLE THIS AFTERNOON IN COASTAL NC...
PERHAPS INCLUDING PORTIONS OF THE SE COASTAL PLAIN. WITH THIS IN
MIND...AN ISOLATED TOR (BRIEF/LOW-END VARIETY)...CANNOT BE RULED OUT
WITH VIGOROUS UPDRAFTS (IF ANY) THIS AFTERNOON...PRIMARILY FAR SE
COASTAL PLAIN (I.E. SAMPSON/WAYNE/CUMBERLAND). -VINCENT
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 311 AM THURSDAY...
THE WEAK MID/UPPER LOW WILL SLOWLY DRIFT DEEP INTO THE SE STATES
FRIDAY. MOST IF NOT ALL THE SCATTERED SHOWERS AND THUNDERSTORMS
SHOULD BE IN OUR SE COUNTIES EARLY IN THE DAY... BEFORE SHIFTING ON
SOUTHWARD AND REDEVELOPING WITH DIURNAL HEATING AGAIN FRIDAY
AFTERNOON. OTHERWISE... PARTLY SUNNY WITH HIGHS IN THE MID TO UPPER
80S. PARTLY CLOUDY TO MOSTLY CLEAR SKIES EXPECTED FRIDAY NIGHT WITH
LOWS IN THE MID TO UPPER 60S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 1255 AM THURSDAY...
DRY WEATHER IS STILL ANTICIPATED GIVEN THE FLOW PATTERN OVER THE
REGION SATURDAY AND SUNDAY. IT APPEARS THAT THERE WILL BE A SLOWLY
INCREASING CHANCE OF MAINLY DIURNAL SHOWERS AND THUNDERSTORMS MONDAY
THROUGH WEDNESDAY. HOWEVER... THERE CONTINUES TO BE SOME MODEL
SPREAD IN WHEN THE MOISTURE/INSTABILITY WILL INCREASE ENOUGH FOR
THIS TO OCCUR. WE WILL CONTINUE THE CURRENT LOW CHANCE POP FOR PM
THUNDERSTORMS MONDAY THROUGH WEDNESDAY. TEMPERATURES SHOULD BE NEAR
THE 30 YEAR AVERAGES FOR LATE JULY THIS WEEKEND... AND ONLY SLOWLY
RISE TO ABOVE NORMAL BY TUE-WED.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 730 AM THURSDAY...
ADVERSE AVIATION CONDITIONS ARE EXPECTED THIS MORNING IN THE FORM OF
LIFR/IFR CEILINGS AT FAY/RDU/RWI...WITH IMPROVEMENT TO VFR EXPECTED
BY NOON. EPISODIC CONVECTION IS EXPECTED THROUGH TONIGHT...LIKELY
AFFECTING ALL TERMINALS...AS A WEAK SFC LOW TRACKS EAST FROM UPSTATE
SOUTH CAROLINA TOWARD THE CAROLINA COAST. CONFIDENCE IN SPECIFIC
DETAILS (I.E. PRECISE TIMING/COVERAGE) REMAINS BELOW NORMAL. AS A
RESULT...EVEN THOUGH THUNDERSTORMS ARE LIKELY TO AFFECT ALL
TERMINALS AT SOME POINT DURING THE TAF PERIOD...EXPLICIT MENTION OF
THUNDER WILL NOT BE MENTIONED WITH THE 12Z TAF ISSUANCE. EXPECT
WINDS TO BE LIGHT/VARIABLE OR SE/ESE AT 5-10 KT THROUGH THE TAF
PERIOD.
LONG TERM: ASIDE FROM A POTENTIAL FOR LINGERING LOW CEILINGS EARLY
FRIDAY MORNING...VFR CONDITIONS WILL PREVAIL THROUGH THE WEEKEND AS
THE AFOREMENTIONED LOW PRESSURE SYSTEM MOVES OFFSHORE AND STALLS OFF
THE SE COAST. A POTENTIAL FOR ADVERSE AVIATION CONDITIONS WILL
RETURN EARLY NEXT WEEK AS THE CENTRAL CONUS RIDGE SHIFTS EASTWARD
AND A MORE AGGRESSIVE /ACTIVE/ NW FLOW ALOFT DEVELOPS OVER THE
CAROLINAS AND MID-ATLANTIC. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD/VINCENT
SHORT TERM...PWB
LONG TERM...PWB
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
736 AM EDT THU JUL 23 2015
.SYNOPSIS...
LOW PRESSURE OVER NORTHERN SOUTH CAROLINA WILL MOVE EAST ALONG A
STALLED FRONT TODAY AND OFF THE COAST TONIGHT. THIS LOW WILL PUSH
THE FRONT INTO GEORGIA FOR THIS WEEKEND. HIGH PRESSURE WILL BUILD
DOWN FROM THE NORTH...WITH A DRYING TREND EXPECTED THIS WEEKEND INTO
EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM THURSDAY...LOW PRESSURE CENTERED OVER THE SC SANDHILLS
WILL MOVE EASTWARD ALONG A STATIONARY FRONT TODAY...EXITING INTO THE
ATLANTIC OCEAN TONIGHT. MODELS ARE ALMOST UNANIMOUS IN THEIR
DEPICTION OF A LARGE CLUSTER OF THUNDERSTORMS DEVELOPING WITHIN A
REGION OF LOW-LEVEL CONVERGENCE AND LARGE INSTABILITY OVER SOUTHERN
NORTH CAROLINA JUST NORTH OF THE STATIONARY FRONT LATE THIS MORNING.
SURFACE CAPE IS PREDICTED TO GROW AS LARGE AS 3000 J/KG WITH LIFTED
INDICES TO -6. 700 MB WINDS INCREASING TO 25 KT SHOULD INCREASE BULK
SHEAR VALUES JUST ENOUGH TO PRODUCE ORGANIZED MULTICELLULAR STORMS
TODAY...WITH COLD POOL EFFECTS LIKELY PUSHING THE CLUSTER
SOUTHEASTWARD ACROSS THE CAPE FEAR AREA EARLY THIS AFTERNOON AND
INTO NORTHEASTERLY SOUTH CAROLINA BY MID TO LATE AFTERNOON.
IMPACTS FROM THESE STORMS COULD BE CONSIDERABLE. COMPUTED
EQUILIBRIUM PARCEL HEIGHTS NEAR 50000 FT AND LOTS OF INSTABILITY
ABOVE THE -20C LEVEL INDICATES THESE STORMS COULD BE ENORMOUS
LIGHTNING PRODUCERS WITH PLENTY OF ICE/GRAUPEL GENERATION ALOFT.
ALTHOUGH NO DRY LAYERS ARE EVIDENT IN FORECAST SOUNDINGS
PRECIPITATION LOADING RESULTING FROM SUCH VIGOROUS CONVECTION SHOULD
PRODUCE GUSTY WINDS...PARTICULARLY AS THE STORMS ARE SHOWN IN THE
HIGH RESOLUTION WRF-NMM...WRF-ARW...AND HRRR MODELS TO FORM A LARGE
MASSED OUTFLOW PUSHING SOUTHEASTWARD TO THE COAST. WITH THE SYNOPTIC
FRONT STALLED ACROSS THE AREA AND ANTICIPATED BOUNDARY COLLISIONS
THE STORMS SHOULD ALSO BE HEAVY RAIN MAKERS WITH LOCALIZED FLOODING
POSSIBLE. FORECAST RAIN CHANCES HAVE BEEN INCREASED TO 80 PERCENT
ACROSS SE NORTH CAROLINA...FOCUSED ON THE NOON-4 PM TIMEFRAME.
CONVECTION SHOULD TAKE SEVERAL ADDITIONAL HOURS TO PROPAGATE
SOUTHWARD AND AFFECT NE SOUTH CAROLINA WHICH WILL BE LOCATED SOUTH
OF THE STATIONARY FRONT. THIS MEANS SEVERAL ADDITIONAL HOURS OF HOT
SUNSHINE...AND TEMPERATURES HERE WILL RISE INTO THE MID TO UPPER
90S. FORECAST HEAT INDICES ARE JUST BELOW 105-DEGREE HEAT ADVISORY
CRITERIA ACROSS GEORGETOWN...WILLIAMSBURG AND SOUTHERN FLORENCE
COUNTIES.
AN UPPER LEVEL DISTURBANCE CURRENTLY PRODUCING THUNDERSTORMS OVER
CENTRAL TENNESSEE WILL REACH THE EASTERN CAROLINAS THIS EVENING.
THIS COULD HELP CONVECTIVE ACTIVITY TO PERSIST INTO THE EVENING
HOURS EVEN AFTER THE ATMOSPHERE PRETTY MUCH OVERTURNS DURING THE
AFTERNOON. THE LOW WILL SCOOT EASTWARD ALONG THE FRONT OFFSHORE
AFTER MIDNIGHT WITH SURFACE WINDS TURNING NORTHWESTERLY...QUITE AN
ODD DIRECTION FOR THE CAROLINAS IN THE MIDDLE OF SUMMER. THIS IS THE
THIRD COLD FRONTAL PASSAGE OF JULY!
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LATEST MODELS SHOW LOW JUST OFF THE CAPE
FEAR COAST FRI MORNING. EXPECT BEST CONVECTION OVER THE COASTAL
WATERS WITH MOST AREAS SEEING A DEEP FLOW OF DRIER AIR ADVECTING
IN FROM THE NORTH. MID TO UPPER TROUGH WILL PUSH LOW PRESSURE
ALONG LINGERING BOUNDARY SOUTH AND EAST OF AREA THROUGH THE
DAY...BUT PLENTY OF RESIDUAL LOW LEVEL MOISTURE FROM PREVIOUS DAYS
CONVECTION WILL SLOW CLEARING AND COMBINE WITH CONVERGENCE
ASSOCIATED WITH LOW AND OTHER LOCALIZED BOUNDARIES SUCH AS THE SEA
BREEZE TO PRODUCE SOME SHWRS/TSTMS. LOOKS LIKE BEST CHC WILL MOVE
SOUTH THROUGH THE DAY AS HIGH PRESSURE BEGINS TO BUILD DOWN FROM
THE NORTH BUT MAY NOT BE FAST ENOUGH TO ELIMINATE POPS FROM
FORECAST. NAM SHOWS MAIN FOCUS OF CONVECTION ALONG COASTAL SOUTH
CAROLINA WHERE BEST CONVERGENCE SHOULD BE AS WE DEVELOP A N-NE
FLOW. MAY SEE ENOUGH SUBSIDENCE AND DRY AIR THROUGH THE MID TO
UPPER LEVELS BY LATE FRI TO ALLOW FOR ONLY A DECENT STRATOCU
FIELD OVER NC. PCP WATER VALUES OVER 2 INCHES EARLY FRI MORNING
WILL DROP DOWN CLOSE TO AN INCH BY SAT MORNING. LINGERING CLOUDS
AND PCP WILL KEEP TEMPS IN THE 80S MOST OF THE DAY BUT PLACES THAT
SEE SOME SUN MAKE AN APPEARANCE WILL REACH CLOSE TO 90.
BY LATE FRI INTO FRI NIGHT...PLENTY OF DRY AIR AND SUBSIDENCE
THROUGH THE MID TO UPPER LEVELS WILL REACH DOWN OVER THE FORECAST
AREA AS DRY HIGH PRESSURE AT THE SFC NOSES DOWN FROM THE NORTH.
WILL SHOW CLEARING AT THIS TIME AND WILL KEEP PCP OUT OF FORECAST
THROUGH THE REMAINDER OF THE WEEKEND. PLENTY OF BRIGHT JULY
SUNSHINE WILL DRIVE TEMPS UP NEAR NORMAL...CLOSE TO 90 BUT SFC
DEWPOINT TEMPS WILL BE RUNNING IN THE LOW TO MID 60S MOST PLACES
WHICH WILL MAKE FOR A MUCH MORE REFRESHING DAY THAN PREVIOUS ONES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 330 AM THURSDAY...CENTER OF HIGH PRESSURE NOSING DOWN FROM
THE NORTH WILL SHIFT OFF THE MID ATLANTIC COAST ALLOWING WINDS TO
COME AROUND TO A MORE ON SHORE NE TO E FLOW. WEAK HIGH PRESSURE
WILL CONTINUE TO REACH DOWN INTO THE CAROLINAS THROUGH MID WEEK AS
LEE SIDE TROUGH BECOMES MORE PRONOUNCED. RIDGING IN THE MID TO
UPPER LEVELS OVER THE MID WEST WILL BUILD EASTWARD OVER THE
WEEKEND...BUT AS IT BECOMES MORE AMPLIFIES UP THROUGH THE UPPER
MIDWEST BY TUES...A DEEPER NW FLOW ALOFT WILL ALLOW SOME CLOUDS
AND SHORTWAVE ENERGY TO SNEAK INTO AREA BUT RIDGE WILL BUILD BACK
EAST AND UP THE EAST COAST THROUGH MID WEEK AND THEREFORE MAY
INTRODUCE INCREASED CLOUDS AND SHWRS FOR TUES/WED TIME FRAME BUT
OVERALL SHWR ACTIVITY SHOULD REMAIN MORE ISOLATED HEADING INTO MID
WEEK AS RIDGE BUILDS BACK IN. THE ON SHORE FLOW DEVELOPING THROUGH
THE PERIOD WILL AID IN BRINGING DEWPOINT TEMPS BACK UP CLOSER TO
70 OR SO...HELPING TO INCREASE AFTN CU AND CHC OF SOME CONVECTIVE
DEVELOPMENT. TEMPS WILL BASICALLY REMAIN AROUND CLIMO.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 12Z...TERMINALS ARE CURRENTLY VFR ALTHOUGH SOME MVFR VSBYS IN
BR COULD OCCUR MAINLY AT KLBT UNTIL 13Z. A WEAK FRONT IS LOCATED
FROM NEAR KFLO TO KMYR. WINDS THIS MORNING WILL BE ESE-SE AT
KILM/KLBT WITH S-SW WINDS ELSEWHERE. THUNDERSTORMS ARE A SURE BET
TODAY AND WILL EVENTUALLY AFFECT EVERY TERMINAL. CONFIDENCE IN EXACT
TIMING IS LOW BUT KLBT SHOULD BE INITIALLY AFFECTED BY LATE MORNING
THEN KILM/KFLO TOWARDS EARLY AFTERNOON. KCRE/KMYR SHOULD BE AFFECTED
MOSTLY IN THE AFTERNOON. TEMPO IFR WITH WIND GUSTS TO 35 KT POSSIBLE
WITH THE STORMS.
THUNDERSTORMS SHOULD END IN THE 21-00Z TIME FRAME WITH VFR LIKELY...
BUT SHOWERS WILL POTENTIAL PERSIST INTO THE EVENING HOURS. WINDS
BECOME LIGHT AND VARIABLE OR LIGHT NW LATE AFTERNOON AND EVENING.
THERE IS A FOG POTENTIAL MAINLY KFLO/KLBT OVERNIGHT WITH LOW TO
MODERATE POTENTIAL FOR IFR.
EXTENDED OUTLOOK...BRIEF MVFR POSSIBLE THROUGH THE PERIOD FROM
ISOLATED CONVECTION. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM THURSDAY...LOW PRESSURE CENTERED OVER THE SOUTH
CAROLINA SANDHILLS WILL MOVE EASTWARD TODAY ALONG A WEAK STATIONARY
FRONT. THIS FRONT CURRENTLY SITS JUST NORTH OF CAPE FEAR AND IS
OUTLINED BY A SHIFT IN WIND DIRECTIONS FROM SOUTHERLY ALONG THE SC
COAST TO SOUTHEASTERLY FROM WRIGHTSVILLE BEACH AND SURF CITY TO THE
OUTER BANKS.
AS INLAND AREAS HEAT UP QUICKLY THIS MORNING ATMOSPHERIC CONDITIONS
ARE STRONGLY SUPPORTIVE OF A LARGE CLUSTER OF THUNDERSTORMS
DEVELOPING ACROSS SOUTHERN NORTH CAROLINA...DROPPING SOUTHEASTWARD
AND AFFECTING THE COASTAL WATERS DURING THE AFTERNOON. THESE STORMS
WILL LIKELY CONTAIN LARGE AMOUNTS OF LIGHTNING AND SUBSTANTIAL
VISIBILITY RESTRICTIONS IN HEAVY RAIN. SEVERAL OF THE HIGH-
RESOLUTION MODELS INDICATE THE POTENTIAL FOR A STRONG GUST FRONT AT
THE LEADING EDGE OF THE STORMS WHICH MAY PROMPT SPECIAL MARINE
WARNINGS THIS AFTERNOON. MARINERS IN THE CAPE FEAR AREA SHOULD
EXPECT THE LARGEST IMPACT FROM THESE STORMS BETWEEN 1-3 PM...WITH
THE GRAND STAND AND GEORGETOWN AREAS A COUPLE HOURS LATER.
LATE TONIGHT AS THE LOW SHIFTS EASTWARD ALONG THE FRONT AND ENTERS
THE ATLANTIC OCEAN SURFACE WINDS WILL SHIFT NORTHWESTERLY AND MAY
INCREASE TO 10-15 KT LATE. OUTSIDE OF THUNDERSTORMS SEAS SHOULD
AVERAGE 2 FEET TODAY...AND 2-3 FEET TONIGHT.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LOW PRESSURE ALONG LINGERING BOUNDARY
WILL SLIP FARTHER SOUTH THROUGH THE DAY ON FRIDAY. NORTHEAST FLOW
WILL DEVELOP BEHIND THIS BOUNDARY AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTH THROUGH THE WEEKEND. EXPECT WINDS TO REMAIN BELOW
15 KTS ACROSS MOST OF THE WATERS...BUT THERE SHOULD BE SOME
PERIODS OF HIGHER WAVES...UP CLOSER TO 20 KTS. THE WINDS WILL
BEGIN TO VEER AROUND FROM THE NE TO E. THE PERSISTENT STRONGER NE
TO E ON SHORE FLOW WILL PRODUCE SEAS UP TO 3 TO 5 FT...ESPECIALLY
THROUGH SAT NIGHT.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 330 AM...HIGH PRESSURE EXTENDING DOWN INTO THE CAROLINAS
FROM THE NORTHEAST WILL MOVE FARTHER EAST THROUGH THE PERIOD...ALLOWING
WINDS TO LIGHTEN AND VEER TO THE EAST. THE WINDS SHOULD DECREASE TO
10 KTS OR LESS MOST OF THE TIME...BUT SEA BREEZE EACH AFTN WILL
ACT TO ENHANCE OVERALL ON SHORE FLOW. EXPECT SEAS TO BE COMING
DOWN AS WINDS LIGHTEN HEADING THROUGH LATE SUNDAY INTO MONDAY.
THEREFORE SEAS UP TO 3 TO 5 FT EARLY SUNDAY SHOULD DROP TO 2 TO 4
FT SUN NIGHT. AS SHORTER PERIOD WINDWAVE DIMINISHES THROUGH MONDAY
AND WNA CONTINUES TO SHOW A LONGER PERIOD UP TO 11 SEC WAVE MIXING
IN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
648 AM EDT THU JUL 23 2015
.SYNOPSIS...
LOW PRESSURE OVER NORTHERN SOUTH CAROLINA WILL MOVE EAST ALONG A
STALLED FRONT TODAY AND OFF THE COAST TONIGHT. THIS LOW WILL PUSH
THE FRONT INTO GEORGIA FOR THIS WEEKEND. HIGH PRESSURE WILL BUILD
DOWN FROM THE NORTH...WITH A DRYING TREND EXPECTED THIS WEEKEND INTO
EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM THURSDAY...LOW PRESSURE CENTERED OVER THE SC SANDHILLS
WILL MOVE EASTWARD ALONG A STATIONARY FRONT TODAY...EXITING INTO THE
ATLANTIC OCEAN TONIGHT. MODELS ARE ALMOST UNANIMOUS IN THEIR
DEPICTION OF A LARGE CLUSTER OF THUNDERSTORMS DEVELOPING WITHIN A
REGION OF LOW-LEVEL CONVERGENCE AND LARGE INSTABILITY OVER SOUTHERN
NORTH CAROLINA JUST NORTH OF THE STATIONARY FRONT LATE THIS MORNING.
SURFACE CAPE IS PREDICTED TO GROW AS LARGE AS 3000 J/KG WITH LIFTED
INDICES TO -6. 700 MB WINDS INCREASING TO 25 KT SHOULD INCREASE BULK
SHEAR VALUES JUST ENOUGH TO PRODUCE ORGANIZED MULTICELLULAR STORMS
TODAY...WITH COLD POOL EFFECTS LIKELY PUSHING THE CLUSTER
SOUTHEASTWARD ACROSS THE CAPE FEAR AREA EARLY THIS AFTERNOON AND
INTO NORTHEASTERLY SOUTH CAROLINA BY MID TO LATE AFTERNOON.
IMPACTS FROM THESE STORMS COULD BE CONSIDERABLE. COMPUTED
EQUILIBRIUM PARCEL HEIGHTS NEAR 50000 FT AND LOTS OF INSTABILITY
ABOVE THE -20C LEVEL INDICATES THESE STORMS COULD BE ENORMOUS
LIGHTNING PRODUCERS WITH PLENTY OF ICE/GRAUPEL GENERATION ALOFT.
ALTHOUGH NO DRY LAYERS ARE EVIDENT IN FORECAST SOUNDINGS
PRECIPITATION LOADING RESULTING FROM SUCH VIGOROUS CONVECTION SHOULD
PRODUCE GUSTY WINDS...PARTICULARLY AS THE STORMS ARE SHOWN IN THE
HIGH RESOLUTION WRF-NMM...WRF-ARW...AND HRRR MODELS TO FORM A LARGE
MASSED OUTFLOW PUSHING SOUTHEASTWARD TO THE COAST. WITH THE SYNOPTIC
FRONT STALLED ACROSS THE AREA AND ANTICIPATED BOUNDARY COLLISIONS
THE STORMS SHOULD ALSO BE HEAVY RAIN MAKERS WITH LOCALIZED FLOODING
POSSIBLE. FORECAST RAIN CHANCES HAVE BEEN INCREASED TO 80 PERCENT
ACROSS SE NORTH CAROLINA...FOCUSED ON THE NOON-4 PM TIMEFRAME.
CONVECTION SHOULD TAKE SEVERAL ADDITIONAL HOURS TO PROPAGATE
SOUTHWARD AND AFFECT NE SOUTH CAROLINA WHICH WILL BE LOCATED SOUTH
OF THE STATIONARY FRONT. THIS MEANS SEVERAL ADDITIONAL HOURS OF HOT
SUNSHINE...AND TEMPERATURES HERE WILL RISE INTO THE MID TO UPPER
90S. FORECAST HEAT INDICES ARE JUST BELOW 105-DEGREE HEAT ADVISORY
CRITERIA ACROSS GEORGETOWN...WILLIAMSBURG AND SOUTHERN FLORENCE
COUNTIES.
AN UPPER LEVEL DISTURBANCE CURRENTLY PRODUCING THUNDERSTORMS OVER
CENTRAL TENNESSEE WILL REACH THE EASTERN CAROLINAS THIS EVENING.
THIS COULD HELP CONVECTIVE ACTIVITY TO PERSIST INTO THE EVENING
HOURS EVEN AFTER THE ATMOSPHERE PRETTY MUCH OVERTURNS DURING THE
AFTERNOON. THE LOW WILL SCOOT EASTWARD ALONG THE FRONT OFFSHORE
AFTER MIDNIGHT WITH SURFACE WINDS TURNING NORTHWESTERLY...QUITE AN
ODD DIRECTION FOR THE CAROLINAS IN THE MIDDLE OF SUMMER. THIS IS THE
THIRD COLD FRONTAL PASSAGE OF JULY!
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LATEST MODELS SHOW LOW JUST OFF THE CAPE
FEAR COAST FRI MORNING. EXPECT BEST CONVECTION OVER THE COASTAL
WATERS WITH MOST AREAS SEEING A DEEP FLOW OF DRIER AIR ADVECTING
IN FROM THE NORTH. MID TO UPPER TROUGH WILL PUSH LOW PRESSURE
ALONG LINGERING BOUNDARY SOUTH AND EAST OF AREA THROUGH THE
DAY...BUT PLENTY OF RESIDUAL LOW LEVEL MOISTURE FROM PREVIOUS DAYS
CONVECTION WILL SLOW CLEARING AND COMBINE WITH CONVERGENCE
ASSOCIATED WITH LOW AND OTHER LOCALIZED BOUNDARIES SUCH AS THE SEA
BREEZE TO PRODUCE SOME SHWRS/TSTMS. LOOKS LIKE BEST CHC WILL MOVE
SOUTH THROUGH THE DAY AS HIGH PRESSURE BEGINS TO BUILD DOWN FROM
THE NORTH BUT MAY NOT BE FAST ENOUGH TO ELIMINATE POPS FROM
FORECAST. NAM SHOWS MAIN FOCUS OF CONVECTION ALONG COASTAL SOUTH
CAROLINA WHERE BEST CONVERGENCE SHOULD BE AS WE DEVELOP A N-NE
FLOW. MAY SEE ENOUGH SUBSIDENCE AND DRY AIR THROUGH THE MID TO
UPPER LEVELS BY LATE FRI TO ALLOW FOR ONLY A DECENT STRATOCU
FIELD OVER NC. PCP WATER VALUES OVER 2 INCHES EARLY FRI MORNING
WILL DROP DOWN CLOSE TO AN INCH BY SAT MORNING. LINGERING CLOUDS
AND PCP WILL KEEP TEMPS IN THE 80S MOST OF THE DAY BUT PLACES THAT
SEE SOME SUN MAKE AN APPEARANCE WILL REACH CLOSE TO 90.
BY LATE FRI INTO FRI NIGHT...PLENTY OF DRY AIR AND SUBSIDENCE
THROUGH THE MID TO UPPER LEVELS WILL REACH DOWN OVER THE FORECAST
AREA AS DRY HIGH PRESSURE AT THE SFC NOSES DOWN FROM THE NORTH.
WILL SHOW CLEARING AT THIS TIME AND WILL KEEP PCP OUT OF FORECAST
THROUGH THE REMAINDER OF THE WEEKEND. PLENTY OF BRIGHT JULY
SUNSHINE WILL DRIVE TEMPS UP NEAR NORMAL...CLOSE TO 90 BUT SFC
DEWPOINT TEMPS WILL BE RUNNING IN THE LOW TO MID 60S MOST PLACES
WHICH WILL MAKE FOR A MUCH MORE REFRESHING DAY THAN PREVIOUS ONES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 330 AM THURSDAY...CENTER OF HIGH PRESSURE NOSING DOWN FROM
THE NORTH WILL SHIFT OFF THE MID ATLANTIC COAST ALLOWING WINDS TO
COME AROUND TO A MORE ON SHORE NE TO E FLOW. WEAK HIGH PRESSURE
WILL CONTINUE TO REACH DOWN INTO THE CAROLINAS THROUGH MID WEEK AS
LEE SIDE TROUGH BECOMES MORE PRONOUNCED. RIDGING IN THE MID TO
UPPER LEVELS OVER THE MID WEST WILL BUILD EASTWARD OVER THE
WEEKEND...BUT AS IT BECOMES MORE AMPLIFIES UP THROUGH THE UPPER
MIDWEST BY TUES...A DEEPER NW FLOW ALOFT WILL ALLOW SOME CLOUDS
AND SHORTWAVE ENERGY TO SNEAK INTO AREA BUT RIDGE WILL BUILD BACK
EAST AND UP THE EAST COAST THROUGH MID WEEK AND THEREFORE MAY
INTRODUCE INCREASED CLOUDS AND SHWRS FOR TUES/WED TIME FRAME BUT
OVERALL SHWR ACTIVITY SHOULD REMAIN MORE ISOLATED HEADING INTO MID
WEEK AS RIDGE BUILDS BACK IN. THE ON SHORE FLOW DEVELOPING THROUGH
THE PERIOD WILL AID IN BRINGING DEWPOINT TEMPS BACK UP CLOSER TO
70 OR SO...HELPING TO INCREASE AFTN CU AND CHC OF SOME CONVECTIVE
DEVELOPMENT. TEMPS WILL BASICALLY REMAIN AROUND CLIMO.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...LOOKS LIKE THERE WILL BE LITTLE BEFORE SUNRISE. THE WEAK
MCS WEST OF THE AREA DID NOT MAKE IT. WITH LITTLE IN CONVECTIVE
DEBRIS...TEMPO MVFR FOG IS A GOOD BET AFTER 08Z.
THE FRONT WAVES BACK TO THE NORTH AROUND DAYBREAK WITH MOISTURE
INCREASING LATER IN THE MORNING. TIMING OF THE CONVECTION WILL BE AN
ISSUE...BUT IT IS SAFE TO SAY THAT SHOWERS AND STORMS WILL BE AROUND
TODAY...POSSIBLY NUMEROUS AS DEEP MOISTURE MOVES BACK OVER THE
REGION. LOW PRESSURE FORMING ALONG THE FRONT SHOULD ENHANCE
PRECIPITATION. THERE SHOULD BE MINIMAL CONVECTIVE INHIBITION...A
CHANGE FROM THE PREVIOUS WEEK...WITH CONVECTION EXPECTED TO BEGIN
WITH ONLY MINIMAL HEATING...BY MIDDAY. SOME BRIEF IFR CONDITIONS ARE
LIKELY IN THE HEAVIEST ACTIVITY.
EXTENDED OUTLOOK...BRIEF MVFR POSSIBLE THROUGH THE PERIOD FROM
ISOLATED CONVECTION. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM THURSDAY...LOW PRESSURE CENTERED OVER THE SOUTH
CAROLINA SANDHILLS WILL MOVE EASTWARD TODAY ALONG A WEAK STATIONARY
FRONT. THIS FRONT CURRENTLY SITS JUST NORTH OF CAPE FEAR AND IS
OUTLINED BY A SHIFT IN WIND DIRECTIONS FROM SOUTHERLY ALONG THE SC
COAST TO SOUTHEASTERLY FROM WRIGHTSVILLE BEACH AND SURF CITY TO THE
OUTER BANKS.
AS INLAND AREAS HEAT UP QUICKLY THIS MORNING ATMOSPHERIC CONDITIONS
ARE STRONGLY SUPPORTIVE OF A LARGE CLUSTER OF THUNDERSTORMS
DEVELOPING ACROSS SOUTHERN NORTH CAROLINA...DROPPING SOUTHEASTWARD
AND AFFECTING THE COASTAL WATERS DURING THE AFTERNOON. THESE STORMS
WILL LIKELY CONTAIN LARGE AMOUNTS OF LIGHTNING AND SUBSTANTIAL
VISIBILITY RESTRICTIONS IN HEAVY RAIN. SEVERAL OF THE HIGH-
RESOLUTION MODELS INDICATE THE POTENTIAL FOR A STRONG GUST FRONT AT
THE LEADING EDGE OF THE STORMS WHICH MAY PROMPT SPECIAL MARINE
WARNINGS THIS AFTERNOON. MARINERS IN THE CAPE FEAR AREA SHOULD
EXPECT THE LARGEST IMPACT FROM THESE STORMS BETWEEN 1-3 PM...WITH
THE GRAND STAND AND GEORGETOWN AREAS A COUPLE HOURS LATER.
LATE TONIGHT AS THE LOW SHIFTS EASTWARD ALONG THE FRONT AND ENTERS
THE ATLANTIC OCEAN SURFACE WINDS WILL SHIFT NORTHWESTERLY AND MAY
INCREASE TO 10-15 KT LATE. OUTSIDE OF THUNDERSTORMS SEAS SHOULD
AVERAGE 2 FEET TODAY...AND 2-3 FEET TONIGHT.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LOW PRESSURE ALONG LINGERING BOUNDARY
WILL SLIP FARTHER SOUTH THROUGH THE DAY ON FRIDAY. NORTHEAST FLOW
WILL DEVELOP BEHIND THIS BOUNDARY AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTH THROUGH THE WEEKEND. EXPECT WINDS TO REMAIN BELOW
15 KTS ACROSS MOST OF THE WATERS...BUT THERE SHOULD BE SOME
PERIODS OF HIGHER WAVES...UP CLOSER TO 20 KTS. THE WINDS WILL
BEGIN TO VEER AROUND FROM THE NE TO E. THE PERSISTENT STRONGER NE
TO E ON SHORE FLOW WILL PRODUCE SEAS UP TO 3 TO 5 FT...ESPECIALLY
THROUGH SAT NIGHT.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 330 AM...HIGH PRESSURE EXTENDING DOWN INTO THE CAROLINAS
FROM THE NORTHEAST WILL MOVE FARTHER EAST THROUGH THE PERIOD...ALLOWING
WINDS TO LIGHTEN AND VEER TO THE EAST. THE WINDS SHOULD DECREASE TO
10 KTS OR LESS MOST OF THE TIME...BUT SEA BREEZE EACH AFTN WILL
ACT TO ENHANCE OVERALL ON SHORE FLOW. EXPECT SEAS TO BE COMING
DOWN AS WINDS LIGHTEN HEADING THROUGH LATE SUNDAY INTO MONDAY.
THEREFORE SEAS UP TO 3 TO 5 FT EARLY SUNDAY SHOULD DROP TO 2 TO 4
FT SUN NIGHT. AS SHORTER PERIOD WINDWAVE DIMINISHES THROUGH MONDAY
AND WNA CONTINUES TO SHOW A LONGER PERIOD UP TO 11 SEC WAVE MIXING
IN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...TRA/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
338 AM EDT THU JUL 23 2015
.SYNOPSIS...
LOW PRESSURE OVER NORTHERN SOUTH CAROLINA WILL MOVE EAST ALONG A
STALLED FRONT TODAY AND OFF THE COAST TONIGHT. THIS LOW WILL PUSH
THE FRONT INTO GEORGIA FOR THIS WEEKEND. HIGH PRESSURE WILL BUILD
DOWN FROM THE NORTH...WITH A DRYING TREND EXPECTED THIS WEEKEND INTO
EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM THURSDAY...LOW PRESSURE CENTERED OVER THE SC SANDHILLS
WILL MOVE EASTWARD ALONG A STATIONARY FRONT TODAY...EXITING INTO THE
ATLANTIC OCEAN TONIGHT. MODELS ARE ALMOST UNANIMOUS IN THEIR
DEPICTION OF A LARGE CLUSTER OF THUNDERSTORMS DEVELOPING WITHIN A
REGION OF LOW-LEVEL CONVERGENCE AND LARGE INSTABILITY OVER SOUTHERN
NORTH CAROLINA JUST NORTH OF THE STATIONARY FRONT LATE THIS MORNING.
SURFACE CAPE IS PREDICTED TO GROW AS LARGE AS 3000 J/KG WITH LIFTED
INDICES TO -6. 700 MB WINDS INCREASING TO 25 KT SHOULD INCREASE BULK
SHEAR VALUES JUST ENOUGH TO PRODUCE ORGANIZED MULTICELLULAR STORMS
TODAY...WITH COLD POOL EFFECTS LIKELY PUSHING THE CLUSTER
SOUTHEASTWARD ACROSS THE CAPE FEAR AREA EARLY THIS AFTERNOON AND
INTO NORTHEASTERLY SOUTH CAROLINA BY MID TO LATE AFTERNOON.
IMPACTS FROM THESE STORMS COULD BE CONSIDERABLE. COMPUTED
EQUILIBRIUM PARCEL HEIGHTS NEAR 50000 FT AND LOTS OF INSTABILITY
ABOVE THE -20C LEVEL INDICATES THESE STORMS COULD BE ENORMOUS
LIGHTNING PRODUCERS WITH PLENTY OF ICE/GRAUPEL GENERATION ALOFT.
ALTHOUGH NO DRY LAYERS ARE EVIDENT IN FORECAST SOUNDINGS
PRECIPITATION LOADING RESULTING FROM SUCH VIGOROUS CONVECTION SHOULD
PRODUCE GUSTY WINDS...PARTICULARLY AS THE STORMS ARE SHOWN IN THE
HIGH RESOLUTION WRF-NMM...WRF-ARW...AND HRRR MODELS TO FORM A LARGE
MASSED OUTFLOW PUSHING SOUTHEASTWARD TO THE COAST. WITH THE SYNOPTIC
FRONT STALLED ACROSS THE AREA AND ANTICIPATED BOUNDARY COLLISIONS
THE STORMS SHOULD ALSO BE HEAVY RAIN MAKERS WITH LOCALIZED FLOODING
POSSIBLE. FORECAST RAIN CHANCES HAVE BEEN INCREASED TO 80 PERCENT
ACROSS SE NORTH CAROLINA...FOCUSED ON THE NOON-4 PM TIMEFRAME.
CONVECTION SHOULD TAKE SEVERAL ADDITIONAL HOURS TO PROPAGATE
SOUTHWARD AND AFFECT NE SOUTH CAROLINA WHICH WILL BE LOCATED SOUTH
OF THE STATIONARY FRONT. THIS MEANS SEVERAL ADDITIONAL HOURS OF HOT
SUNSHINE...AND TEMPERATURES HERE WILL RISE INTO THE MID TO UPPER
90S. FORECAST HEAT INDICES ARE JUST BELOW 105-DEGREE HEAT ADVISORY
CRITERIA ACROSS GEORGETOWN...WILLIAMSBURG AND SOUTHERN FLORENCE
COUNTIES.
AN UPPER LEVEL DISTURBANCE CURRENTLY PRODUCING THUNDERSTORMS OVER
CENTRAL TENNESSEE WILL REACH THE EASTERN CAROLINAS THIS EVENING.
THIS COULD HELP CONVECTIVE ACTIVITY TO PERSIST INTO THE EVENING
HOURS EVEN AFTER THE ATMOSPHERE PRETTY MUCH OVERTURNS DURING THE
AFTERNOON. THE LOW WILL SCOOT EASTWARD ALONG THE FRONT OFFSHORE
AFTER MIDNIGHT WITH SURFACE WINDS TURNING NORTHWESTERLY...QUITE AN
ODD DIRECTION FOR THE CAROLINAS IN THE MIDDLE OF SUMMER. THIS IS THE
THIRD COLD FRONTAL PASSAGE OF JULY!
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LATEST MODELS SHOW LOW JUST OFF THE CAPE
FEAR COAST FRI MORNING. EXPECT BEST CONVECTION OVER THE COASTAL
WATERS WITH MOST AREAS SEEING A DEEP FLOW OF DRIER AIR ADVECTING
IN FROM THE NORTH. MID TO UPPER TROUGH WILL PUSH LOW PRESSURE
ALONG LINGERING BOUNDARY SOUTH AND EAST OF AREA THROUGH THE
DAY...BUT PLENTY OF RESIDUAL LOW LEVEL MOISTURE FROM PREVIOUS DAYS
CONVECTION WILL SLOW CLEARING AND COMBINE WITH CONVERGENCE
ASSOCIATED WITH LOW AND OTHER LOCALIZED BOUNDARIES SUCH AS THE SEA
BREEZE TO PRODUCE SOME SHWRS/TSTMS. LOOKS LIKE BEST CHC WILL MOVE
SOUTH THROUGH THE DAY AS HIGH PRESSURE BEGINS TO BUILD DOWN FROM
THE NORTH BUT MAY NOT BE FAST ENOUGH TO ELIMINATE POPS FROM
FORECAST. NAM SHOWS MAIN FOCUS OF CONVECTION ALONG COASTAL SOUTH
CAROLINA WHERE BEST CONVERGENCE SHOULD BE AS WE DEVELOP A N-NE
FLOW. MAY SEE ENOUGH SUBSIDENCE AND DRY AIR THROUGH THE MID TO
UPPER LEVELS BY LATE FRI TO ALLOW FOR ONLY A DECENT STRATOCU
FIELD OVER NC. PCP WATER VALUES OVER 2 INCHES EARLY FRI MORNING
WILL DROP DOWN CLOSE TO AN INCH BY SAT MORNING. LINGERING CLOUDS
AND PCP WILL KEEP TEMPS IN THE 80S MOST OF THE DAY BUT PLACES THAT
SEE SOME SUN MAKE AN APPEARANCE WILL REACH CLOSE TO 90.
BY LATE FRI INTO FRI NIGHT...PLENTY OF DRY AIR AND SUBSIDENCE
THROUGH THE MID TO UPPER LEVELS WILL REACH DOWN OVER THE FORECAST
AREA AS DRY HIGH PRESSURE AT THE SFC NOSES DOWN FROM THE NORTH.
WILL SHOW CLEARING AT THIS TIME AND WILL KEEP PCP OUT OF FORECAST
THROUGH THE REMAINDER OF THE WEEKEND. PLENTY OF BRIGHT JULY
SUNSHINE WILL DRIVE TEMPS UP NEAR NORMAL...CLOSE TO 90 BUT SFC
DEWPOINT TEMPS WILL BE RUNNING IN THE LOW TO MID 60S MOST PLACES
WHICH WILL MAKE FOR A MUCH MORE REFRESHING DAY THAN PREVIOUS ONES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 330 AM THURSDAY...CENTER OF HIGH PRESSURE NOSING DOWN FROM
THE NORTH WILL SHIFT OFF THE MID ATLANTIC COAST ALLOWING WINDS TO
COME AROUND TO A MORE ON SHORE NE TO E FLOW. WEAK HIGH PRESSURE
WILL CONTINUE TO REACH DOWN INTO THE CAROLINAS THROUGH MID WEEK AS
LEE SIDE TROUGH BECOMES MORE PRONOUNCED. RIDGING IN THE MID TO
UPPER LEVELS OVER THE MID WEST WILL BUILD EASTWARD OVER THE
WEEKEND...BUT AS IT BECOMES MORE AMPLIFIES UP THROUGH THE UPPER
MIDWEST BY TUES...A DEEPER NW FLOW ALOFT WILL ALLOW SOME CLOUDS
AND SHORTWAVE ENERGY TO SNEAK INTO AREA BUT RIDGE WILL BUILD BACK
EAST AND UP THE EAST COAST THROUGH MID WEEK AND THEREFORE MAY
INTRODUCE INCREASED CLOUDS AND SHWRS FOR TUES/WED TIME FRAME BUT
OVERALL SHWR ACTIVITY SHOULD REMAIN MORE ISOLATED HEADING INTO MID
WEEK AS RIDGE BUILDS BACK IN. THE ON SHORE FLOW DEVELOPING THROUGH
THE PERIOD WILL AID IN BRINGING DEWPOINT TEMPS BACK UP CLOSER TO
70 OR SO...HELPING TO INCREASE AFTN CU AND CHC OF SOME CONVECTIVE
DEVELOPMENT. TEMPS WILL BASICALLY REMAIN AROUND CLIMO.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...LOOKS LIKE
THERE WILL BE LITTLE BEFORE SUNRISE. THE WEAK MCS WEST OF THE AREA
DID NOT MAKE IT. WITH LITTLE IN CONVECTIVE DEBRIS...TEMPO MVFR FOG
IS A GOOD BET AFTER 08Z.
THE FRONT WAVES BACK TO THE NORTH AROUND DAYBREAK WITH MOISTURE
INCREASING LATER IN THE MORNING. TIMING OF THE CONVECTION WILL BE AN
ISSUE...BUT IT IS SAFE TO SAY THAT SHOWERS AND STORMS WILL BE AROUND
TODAY...POSSIBLY NUMEROUS AS DEEP MOISTURE MOVES BACK OVER THE
REGION. LOW PRESSURE FORMING ALONG THE FRONT SHOULD ENHANCE
PRECIPITATION. THERE SHOULD BE MINIMAL CONVECTIVE INHIBITION...A
CHANGE FROM THE PREVIOUS WEEK...WITH CONVECTION EXPECTED TO BEGIN
WITH ONLY MINIMAL HEATING...BY MIDDAY. SOME BRIEF IFR CONDITIONS ARE
LIKELY IN THE HEAVIEST ACTIVITY.
EXTENDED OUTLOOK...BRIEF MVFR POSSIBLE THROUGH THE PERIOD FROM
ISOLATED CONVECTION. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM THURSDAY...LOW PRESSURE CENTERED OVER THE SOUTH
CAROLINA SANDHILLS WILL MOVE EASTWARD TODAY ALONG A WEAK STATIONARY
FRONT. THIS FRONT CURRENTLY SITS JUST NORTH OF CAPE FEAR AND IS
OUTLINED BY A SHIFT IN WIND DIRECTIONS FROM SOUTHERLY ALONG THE SC
COAST TO SOUTHEASTERLY FROM WRIGHTSVILLE BEACH AND SURF CITY TO THE
OUTER BANKS.
AS INLAND AREAS HEAT UP QUICKLY THIS MORNING ATMOSPHERIC CONDITIONS
ARE STRONGLY SUPPORTIVE OF A LARGE CLUSTER OF THUNDERSTORMS
DEVELOPING ACROSS SOUTHERN NORTH CAROLINA...DROPPING SOUTHEASTWARD
AND AFFECTING THE COASTAL WATERS DURING THE AFTERNOON. THESE STORMS
WILL LIKELY CONTAIN LARGE AMOUNTS OF LIGHTNING AND SUBSTANTIAL
VISIBILITY RESTRICTIONS IN HEAVY RAIN. SEVERAL OF THE HIGH-
RESOLUTION MODELS INDICATE THE POTENTIAL FOR A STRONG GUST FRONT AT
THE LEADING EDGE OF THE STORMS WHICH MAY PROMPT SPECIAL MARINE
WARNINGS THIS AFTERNOON. MARINERS IN THE CAPE FEAR AREA SHOULD
EXPECT THE LARGEST IMPACT FROM THESE STORMS BETWEEN 1-3 PM...WITH
THE GRAND STAND AND GEORGETOWN AREAS A COUPLE HOURS LATER.
LATE TONIGHT AS THE LOW SHIFTS EASTWARD ALONG THE FRONT AND ENTERS
THE ATLANTIC OCEAN SURFACE WINDS WILL SHIFT NORTHWESTERLY AND MAY
INCREASE TO 10-15 KT LATE. OUTSIDE OF THUNDERSTORMS SEAS SHOULD
AVERAGE 2 FEET TODAY...AND 2-3 FEET TONIGHT.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...LOW PRESSURE ALONG LINGERING BOUNDARY
WILL SLIP FARTHER SOUTH THROUGH THE DAY ON FRIDAY. NORTHEAST FLOW
WILL DEVELOP BEHIND THIS BOUNDARY AS HIGH PRESSURE BUILDS DOWN
FROM THE NORTH THROUGH THE WEEKEND. EXPECT WINDS TO REMAIN BELOW
15 KTS ACROSS MOST OF THE WATERS...BUT THERE SHOULD BE SOME
PERIODS OF HIGHER WAVES...UP CLOSER TO 20 KTS. THE WINDS WILL
BEGIN TO VEER AROUND FROM THE NE TO E. THE PERSISTENT STRONGER NE
TO E ON SHORE FLOW WILL PRODUCE SEAS UP TO 3 TO 5 FT...ESPECIALLY
THROUGH SAT NIGHT.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 330 AM...HIGH PRESSURE EXTENDING DOWN INTO THE CAROLINAS
FROM THE NORTHEAST WILL MOVE FARTHER EAST THROUGH THE PERIOD...ALLOWING
WINDS TO LIGHTEN AND VEER TO THE EAST. THE WINDS SHOULD DECREASE TO
10 KTS OR LESS MOST OF THE TIME...BUT SEA BREEZE EACH AFTN WILL
ACT TO ENHANCE OVERALL ON SHORE FLOW. EXPECT SEAS TO BE COMING
DOWN AS WINDS LIGHTEN HEADING THROUGH LATE SUNDAY INTO MONDAY.
THEREFORE SEAS UP TO 3 TO 5 FT EARLY SUNDAY SHOULD DROP TO 2 TO 4
FT SUN NIGHT. AS SHORTER PERIOD WINDWAVE DIMINISHES THROUGH MONDAY
AND WNA CONTINUES TO SHOW A LONGER PERIOD UP TO 11 SEC WAVE MIXING
IN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...TRA/DL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
944 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 944 PM CDT FRI JUL 24 2015
SHOWERS APPROACHING FROM THE NW ARE DISSIPATING...BUT WILL KEEP
THE 20 POPS NEAR THE INTERNATIONAL BORDER UNTIL 4Z JUST IN CASE
ONE SNEAKS INTO THE REGION. FORECAST IN GOOD SHAPE AND NO CHANGES
PLANNED.
UPDATE ISSUED AT 646 PM CDT FRI JUL 24 2015
SHOWERS ACROSS THE EASTERN FA SHOULD MOVE OUT OF THE REGION BY
01Z. THERE IS ANOTHER AREA OF SHOWERS/THUNDER APPROACHING FROM THE
NORTHWEST...AND THE HRRR INDICATES ENOUGH FORCING TO HOLD THIS
ACTIVITY TOGETHER SO THAT IT CAN REACH THE DVL BASIN 01Z-04Z..AND
DID INSERT ISOLD POPS FOR THIS TIMEFRAME.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 308 PM CDT FRI JUL 24 2015
EXPECT A WARM WEEKEND OVER THE AREA WITH HIGHS WELL INTO THE
80S AS A BROAD UPPER RIDGE WILL BE IN PLACE. THE USUAL WEAK SHORT
WAVES WILL MOVE THROUGH THE AREA...BUT MAINLY IMPACT SOUTH DAKOTA
SATURDAY NIGHT AS AN UPPER WAVE MOVES THROUGH AND INTERACTS WITH A
WEAK LOW LEVEL JET. MODELS ALL OVER THE PLACE WITH PCPN PLACEMENT.
GEM TOO FAR NORTH OVER SE ND AND NAM/GFS MORE OVER FAR NRN SD AND
THE ECMWF A BIT FARTHER SOUTH. NET RESULT WAS TO KEEP CHC POPS IN
SRN FCST AREA SAT NIGHT. UNTIL THEN DRY TONIGHT INTO MOST OF
SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 PM CDT FRI JUL 24 2015
SHORT WAVE MOVES EAST SUNDAY WITH ANY PCPN CHANCES ENDING IN
WCNTRL MN SUNDAY MORNING. SUNDAY WILL BE VERY WARM AND HUMID WITH
HIGHS CLOSE TO 90 IN IN THE SRN VALLEY. WARM AND HUMID INTO
MONDAY. THERE COULD BE AN ISOLD STORM SUN-SUN NIGHT BUT NOT A
CLEAR SIGNAL IN MODELS BUT PATTERN WOULD SUPPORT SOME AFTN HEATING
STORMS AND A LINGERING STORM OR TWO SUNDAY NIGHT. MONDAY WILL
FEATURE A BUILDING 500 MB RIDGE EAST OF A PRETTY STRONG UPPER
TROUGH OVER WRN MONTANA. WILL MAINTAIN SOME CHC POPS MONDAY BUT
MAIN FOCUS WILL BE IN ERN MT/WRN ND MONDAY.
MONDAY NIGHT TO FRIDAY...MODELS CONTINUE TO BRING A STRONG UPPER
WAVE ALONG THE INTERNATIONAL BORDER ON TUESDAY AND WEDNESDAY.
AHEAD OF THIS FEATURE A HOT AND HUMID AIRMASS WILL BE IN PLACE ON
TUESDAY MORNING...THAT WILL FUEL THUNDERSTORM DEVELOPMENT AS THE
SYSTEM ENHANCES LIFT ACROSS THE DAKOTAS TUESDAY. UNCERTAINTY
EXISTS WITH THE STRENGTH OF THE CAP AND SOUTHERN EXTENT OF PRECIP.
FROPA PASSES EAST ON WEDNESDAY WITH BEST CHANCES FOR THUNDER ALONG
THE NORTHERN TIER...WHERE COLDER TEMPS LOFT RESIDE. WEDNESDAY TO
FRIDAY WILL BE OVERALL DRY WITH TEMPS IN THE UPR 70S TO LOW
80S...AT TO SLIGHTLY BELOW END OF JULY NORMALS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 646 PM CDT FRI JUL 24 2015
VFR CONDITIONS THROUGH THE PERIOD...WITH THUNDER CHANCES VERY LOW.
WINDS WILL BE LIGHT TONIGHT AND INTO SATURDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...RIDDLE
LONG TERM...JK/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
928 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 908 PM CDT FRI JUL 24 2015
CONVECTION OVER THE NORTH CENTRAL HAS WEAKENED OVER THE PAST
HOUR...SO WILL LOWER POPS TO SLIGHT CHANCE...REMOVING AFTER AN
HOUR OR SO. NEXT ROUND OF WEAK WAVES CONTINUE TO SLOWLY APPROACH
FROM THE SOUTHWEST...SO WILL KEEP POPS IN FOR MAINLY LATE
TONIGHT/EARLY SATURDAY MORNING OVER THE SOUTHWEST. UPDATES HAVE
BEEN SENT.
UPDATE ISSUED AT 610 PM CDT FRI JUL 24 2015
A FEW THUNDERSTORMS CONTINUE OVER NORTHWEST NORTH DAKOTA...BUT
THESE SHOULD BE DIMINISHING SOON WITH LOSS OF DAYTIME HEATING.
OTHERWISE...A QUIET EVENING IS IN STORE FOR MOST LOCATIONS BEFORE
THE NEXT SHORT WAVE APPROACHES SOUTHWESTERN AREAS...BRINGING LOW
SHOWER/THUNDERSTORM CHANCES.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 256 PM CDT FRI JUL 24 2015
LATEST SURFACE ANALYSIS HAS A SURFACE HIGH PRESSURE REGION OVER
THE CENTRAL DAKOTAS WITHE A WEAK TROUGH OF LOW PRESSURE AND AN
ASSOCIATED DEWPOINT DISCONTINUITY ACROSS WESTERN NORTH DAKOTA. A
CU FIELD IS ASSOCIATED WITH THE DEWPOINT DISCONTINUITY. THE
FORECAST TRENDS IN THE HRRR PLACE SOME SCATTERED THUNDERSTORMS
ACROSS WESTERN NORTH DAKOTA THIS AFTERNOON/EVENING. THE NAM/GFS
ARE DRY. BUFKIT SOUNDINGS SHOW THE CAP ERODING BUT DONT THINK
THERE WILL BE ENOUGH FORCING FOR CONVECTIVE INITIATION TODAY.
WILL FOLLOW THE DRYER NAM SOLUTION THROUGH THIS EVENING.
OVERNIGHT AND SATURDAY NAM/ECMWF/GFS ALL BRING THE H500 RIDGE
THROUGH THE STATE. THIS POSITIONS AN H500 TROUGH OVER THE
NORTHWEST US TO BRING SOME SHORTWAVE ENERGY INTO THE REGION
SATURDAY. WILL TREND CHANCE POPS ACROSS THE WEST AND SLIGHT CHANCE
CENTRAL BY SATURDAY AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 256 PM CDT FRI JUL 24 2015
CHANCES OF THUNDERSTORMS THROUGH THE WEEKEND...WITH THE POTENTIAL
FOR STRONGER THUNDERSTORMS ON MONDAY. THEN A MAINLY DRY FORECAST BY
MID-WEEK.
ZONAL MID LEVEL FLOW SATURDAY AND INTO SATURDAY NIGHT KEEPS WEAK
WAVES PASSING THROUGH THE NORTHERN PLAINS WITH SMALL CHANCES FOR
THUNDERSTORMS. ON SATURDAY NIGHT THE MODELS INDICATE SCATTERED
THUNDERSTORMS MAINLY ACROSS SOUTHERN NORTH DAKOTA WITH UPPER LEVEL
SHORTWAVE ENERGY MOVING EASTWARD ACROSS SOUTH DAKOTA AND SOUTHERN
NORTH DAKOTA.
ON SUNDAY WEAK BROAD RIDGING DEVELOPS OVER NORTH DAKOTA AS A
LONGWAVE TROUGH MOVES INTO AND DIGS OFF THE WEST COAST...BUT UPPER
LEVEL ENERGY MOVING THROUGH THE UPPER LEVEL FLOW WILL KEEP A CHANCE
OF THUNDERSTORMS IN THE FORECAST.
BY MONDAY CHANCES FOR WIDESPREAD STORMS INCREASE AS THE UPPER LEVEL
LONG WAVE TROUGH MOVES ACROSS THE ROCKIES. SOUTHWEST FLOW ALOFT
AHEAD OF THE TROUGH...AND A GUSTY SOUTHERLY SURFACE FLOW WITH
SURFACE LOW PRESSURE IN THE FRONT RANGE...INCREASES MOISTURE AND
INSTABILITY. THE FORECAST CAPE AND SHEAR PARAMETERS WOULD BE
SUFFICIENT FOR A MENTION OF SEVERE STORMS. THE STORM PREDICTION
CENTER DOES INDICATE A SLIGHT CHANCE OF SEVERE STORMS OVER WESTERN
AND CENTRAL NORTH DAKOTA IN THEIR DAY 4 OUTLOOK (MONDAY AND MONDAY
NIGHT). WILL NOT MENTION SEVERE WORDING JUST YET...BUT LATER SHIFTS
WILL NEED TO TAKE A CLOSER LOOK AT THE SYNOPTIC SETUP.
ON TUESDAY THE MODELS LIFT THE LONGWAVE TROUGH NORTHEASTWARD ACROSS
NORTH DAKOTA AND INTO MANITOBA. THIS WILL KEEP A CHANCE OF SHOWERS
AND THUNDERSTORMS IN OUR AREA...BUT ALSO MOVES A STRONGER SURFACE
LOW AND COLD FRONT ACROSS THE DAKOTAS. GUSTY WEST WINDS ON TUESDAY
WILL USHER IN COOLER AIR TO OUR REGION. LOOKING AT HIGHS ON TUESDAY
AND WEDNESDAY IN THE 70S TO LOWER 80S.
MAINLY DRY THURSDAY AND FRIDAY WITH NORTHWEST FLOW ALOFT...AND HIGHS
IN THE 80S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 610 PM CDT FRI JUL 24 2015
ISOLD THUNDERSTORMS NORTHWEST EARLY THIS EVENING. ISOLD
THUNDERSTORMS POSSIBLE OVERNIGHT SOUTHWEST...SPREADING EAST ON
SATURDAY AND INCREASING IN COVERAGE. OTHERWISE...VFR CONDITIONS
EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...WAA
LONG TERM...JV
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
646 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 646 PM CDT FRI JUL 24 2015
SHOWERS ACROSS THE EASTERN FA SHOULD MOVE OUT OF THE REGION BY
01Z. THERE IS ANOTHER AREA OF SHOWERS/THUNDER APPROACHING FROM THE
NORTHWEST...AND THE HRRR INDICATES ENOUGH FORCING TO HOLD THIS
ACTIVITY TOGETHER SO THAT IT CAN REACH THE DVL BASIN 01Z-04Z..AND
DID INSERT ISOLD POPS FOR THIS TIMEFRAME.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 308 PM CDT FRI JUL 24 2015
EXPECT A WARM WEEKEND OVER THE AREA WITH HIGHS WELL INTO THE
80S AS A BROAD UPPER RIDGE WILL BE IN PLACE. THE USUAL WEAK SHORT
WAVES WILL MOVE THROUGH THE AREA...BUT MAINLY IMPACT SOUTH DAKOTA
SATURDAY NIGHT AS AN UPPER WAVE MOVES THROUGH AND INTERACTS WITH A
WEAK LOW LEVEL JET. MODELS ALL OVER THE PLACE WITH PCPN PLACEMENT.
GEM TOO FAR NORTH OVER SE ND AND NAM/GFS MORE OVER FAR NRN SD AND
THE ECMWF A BIT FARTHER SOUTH. NET RESULT WAS TO KEEP CHC POPS IN
SRN FCST AREA SAT NIGHT. UNTIL THEN DRY TONIGHT INTO MOST OF
SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 PM CDT FRI JUL 24 2015
SHORT WAVE MOVES EAST SUNDAY WITH ANY PCPN CHANCES ENDING IN
WCNTRL MN SUNDAY MORNING. SUNDAY WILL BE VERY WARM AND HUMID WITH
HIGHS CLOSE TO 90 IN IN THE SRN VALLEY. WARM AND HUMID INTO
MONDAY. THERE COULD BE AN ISOLD STORM SUN-SUN NIGHT BUT NOT A
CLEAR SIGNAL IN MODELS BUT PATTERN WOULD SUPPORT SOME AFTN HEATING
STORMS AND A LINGERING STORM OR TWO SUNDAY NIGHT. MONDAY WILL
FEATURE A BUILDING 500 MB RIDGE EAST OF A PRETTY STRONG UPPER
TROUGH OVER WRN MONTANA. WILL MAINTAIN SOME CHC POPS MONDAY BUT
MAIN FOCUS WILL BE IN ERN MT/WRN ND MONDAY.
MONDAY NIGHT TO FRIDAY...MODELS CONTINUE TO BRING A STRONG UPPER
WAVE ALONG THE INTERNATIONAL BORDER ON TUESDAY AND WEDNESDAY.
AHEAD OF THIS FEATURE A HOT AND HUMID AIRMASS WILL BE IN PLACE ON
TUESDAY MORNING...THAT WILL FUEL THUNDERSTORM DEVELOPMENT AS THE
SYSTEM ENHANCES LIFT ACROSS THE DAKOTAS TUESDAY. UNCERTAINTY
EXISTS WITH THE STRENGTH OF THE CAP AND SOUTHERN EXTENT OF PRECIP.
FROPA PASSES EAST ON WEDNESDAY WITH BEST CHANCES FOR THUNDER ALONG
THE NORTHERN TIER...WHERE COLDER TEMPS LOFT RESIDE. WEDNESDAY TO
FRIDAY WILL BE OVERALL DRY WITH TEMPS IN THE UPR 70S TO LOW
80S...AT TO SLIGHTLY BELOW END OF JULY NORMALS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 646 PM CDT FRI JUL 24 2015
VFR CONDITIONS THROUGH THE PERIOD...WITH THUNDER CHANCES VERY LOW.
WINDS WILL BE LIGHT TONIGHT AND INTO SATURDAY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...RIDDLE
LONG TERM...JK/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
622 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 610 PM CDT FRI JUL 24 2015
A FEW THUNDERSTORMS CONTINUE OVER NORTHWEST NORTH DAKOTA...BUT
THESE SHOULD BE DIMINISHING SOON WITH LOSS OF DAYTIME HEATING.
OTHERWISE...A QUIET EVENING IS IN STORE FOR MOST LOCATIONS BEFORE
THE NEXT SHORT WAVE APPROACHES SOUTHWESTERN AREAS...BRINGING LOW
SHOWER/THUNDERSTORM CHANCES.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 256 PM CDT FRI JUL 24 2015
LATEST SURFACE ANALYSIS HAS A SURFACE HIGH PRESSURE REGION OVER
THE CENTRAL DAKOTAS WITHE A WEAK TROUGH OF LOW PRESSURE AND AN
ASSOCIATED DEWPOINT DISCONTINUITY ACROSS WESTERN NORTH DAKOTA. A
CU FIELD IS ASSOCIATED WITH THE DEWPOINT DISCONTINUITY. THE
FORECAST TRENDS IN THE HRRR PLACE SOME SCATTERED THUNDERSTORMS
ACROSS WESTERN NORTH DAKOTA THIS AFTERNOON/EVENING. THE NAM/GFS
ARE DRY. BUFKIT SOUNDINGS SHOW THE CAP ERODING BUT DONT THINK
THERE WILL BE ENOUGH FORCING FOR CONVECTIVE INITIATION TODAY.
WILL FOLLOW THE DRYER NAM SOLUTION THROUGH THIS EVENING.
OVERNIGHT AND SATURDAY NAM/ECMWF/GFS ALL BRING THE H500 RIDGE
THROUGH THE STATE. THIS POSITIONS AN H500 TROUGH OVER THE
NORTHWEST US TO BRING SOME SHORTWAVE ENERGY INTO THE REGION
SATURDAY. WILL TREND CHANCE POPS ACROSS THE WEST AND SLIGHT CHANCE
CENTRAL BY SATURDAY AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 256 PM CDT FRI JUL 24 2015
CHANCES OF THUNDERSTORMS THROUGH THE WEEKEND...WITH THE POTENTIAL
FOR STRONGER THUNDERSTORMS ON MONDAY. THEN A MAINLY DRY FORECAST BY
MID-WEEK.
ZONAL MID LEVEL FLOW SATURDAY AND INTO SATURDAY NIGHT KEEPS WEAK
WAVES PASSING THROUGH THE NORTHERN PLAINS WITH SMALL CHANCES FOR
THUNDERSTORMS. ON SATURDAY NIGHT THE MODELS INDICATE SCATTERED
THUNDERSTORMS MAINLY ACROSS SOUTHERN NORTH DAKOTA WITH UPPER LEVEL
SHORTWAVE ENERGY MOVING EASTWARD ACROSS SOUTH DAKOTA AND SOUTHERN
NORTH DAKOTA.
ON SUNDAY WEAK BROAD RIDGING DEVELOPS OVER NORTH DAKOTA AS A
LONGWAVE TROUGH MOVES INTO AND DIGS OFF THE WEST COAST...BUT UPPER
LEVEL ENERGY MOVING THROUGH THE UPPER LEVEL FLOW WILL KEEP A CHANCE
OF THUNDERSTORMS IN THE FORECAST.
BY MONDAY CHANCES FOR WIDESPREAD STORMS INCREASE AS THE UPPER LEVEL
LONG WAVE TROUGH MOVES ACROSS THE ROCKIES. SOUTHWEST FLOW ALOFT
AHEAD OF THE TROUGH...AND A GUSTY SOUTHERLY SURFACE FLOW WITH
SURFACE LOW PRESSURE IN THE FRONT RANGE...INCREASES MOISTURE AND
INSTABILITY. THE FORECAST CAPE AND SHEAR PARAMETERS WOULD BE
SUFFICIENT FOR A MENTION OF SEVERE STORMS. THE STORM PREDICTION
CENTER DOES INDICATE A SLIGHT CHANCE OF SEVERE STORMS OVER WESTERN
AND CENTRAL NORTH DAKOTA IN THEIR DAY 4 OUTLOOK (MONDAY AND MONDAY
NIGHT). WILL NOT MENTION SEVERE WORDING JUST YET...BUT LATER SHIFTS
WILL NEED TO TAKE A CLOSER LOOK AT THE SYNOPTIC SETUP.
ON TUESDAY THE MODELS LIFT THE LONGWAVE TROUGH NORTHEASTWARD ACROSS
NORTH DAKOTA AND INTO MANITOBA. THIS WILL KEEP A CHANCE OF SHOWERS
AND THUNDERSTORMS IN OUR AREA...BUT ALSO MOVES A STRONGER SURFACE
LOW AND COLD FRONT ACROSS THE DAKOTAS. GUSTY WEST WINDS ON TUESDAY
WILL USHER IN COOLER AIR TO OUR REGION. LOOKING AT HIGHS ON TUESDAY
AND WEDNESDAY IN THE 70S TO LOWER 80S.
MAINLY DRY THURSDAY AND FRIDAY WITH NORTHWEST FLOW ALOFT...AND HIGHS
IN THE 80S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 610 PM CDT FRI JUL 24 2015
ISOLD THUNDERSTORMS NORTHWEST EARLY THIS EVENING. ISOLD
THUNDERSTORMS POSSIBLE OVERNIGHT SOUTHWEST...SPREADING EAST ON
SATURDAY AND INCREASING IN COVERAGE. OTHERWISE...VFR CONDITIONS
EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...WAA
LONG TERM...JV
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
300 PM CDT THU JUL 23 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 300 PM CDT THU JUL 23 2015
THIS EVENING AND TONIGHT SEVERE POTENTIAL...FRONT IS CURRENTLY
(20Z) LOCATED FROM NORTH OF WINNIPEG INTO NORTH CENTRAL NORTH
DAKOTA TO NEAR DICKINSON. THUNDERSTORMS HAVE ALREADY INITIATED
ALONG THIS FEATURE IN CANADA (WHERE THE MID- LEVEL CAP IS
WEAKER)...AND WOULD EXPECT THAT THE FORCING ALONG THIS FEATURE IN
NORTH DAKOTA COMBINED WITH A WEAKENING CAP WILL BE ABLE TO
INITIATE STORMS BY MID-LATE AFTERNOON ACROSS CENTRAL NORTH DAKOTA.
MLCAPE 2000-4000 J/KG EXISTS AHEAD OF THIS FEATURE (AT LEAST ALONG
AND WEST OF THE RED RIVER VALLEY). ANTICIPATE ACTIVITY THAT
DEVELOPS WEST OF THE REGION WILL ORGANIZE INTO SOME SORT OF
EASTWARD MOVING COMPLEX...CONSIDERING THAT GUIDANCE INDICATES
INCREASING DEEP LAYER SHEAR (40 KNOT 500MB JET) AND A DEVELOPING
40 KNOT 850MB JET. IN FACT...HRRR HAS BEEN CONSISTENT RUN TO RUN
SHOWING A QLCS EVENT WITH AREAS OF SEVERE WIND GUSTS ACROSS E ND
AND ADJACENT PORTIONS OF MN. SPC IN ON BOARD WITH THIS ASSESSMENT
INDICATING AN ENHANCED RISK OF SEVERE STORMS FOR DAMAGING WINDS. QLCS
TORNADO ALSO POSSIBLE...ESPECIALLY SE ND WHERE 0-3KM SHEAR WILL
BE WEST 30-40 KNOTS. BRIEF HEAVY RAIN LIKELY...BUT THE SYSTEM
APPEARS IT WILL BE MORE PROGRESSIVE TO PREVENT WIDESPREAD FLASH
FLOOD POTENTIAL. USED THE LATEST HRRR FOR TIMING OF POPS.
FRIDAY-FRIDAY NIGHT...ZONAL FLOW DEVELOPS AND ALTHOUGH
THUNDERSTORMS MAY BE POSSIBLE WITH ANY WEAK FAST MOVING
WAVE...MOST GUIDANCE INDICATES INSTABILITY (LOW LEVEL MOIST AXIS)
WILL BE EAST OF THE REGION BY 18Z FRIDAY. KEPT WITH A MOSTLY DRY
FORECAST AND COOLER (NEAR NORMAL) TEMPERATURES.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 PM CDT THU JUL 23 2015
SATURDAY-SUNDAY...ZONAL FLOW CONTINUES...WITH NO STRONG SIGNAL FOR
PRECIPITATION AMONG THE MODELS. THERE ARE SOME MODEL DIFFERENCES
SATURDAY/SATURDAY NIGHT WITH LOW LEVEL MOISTURE RETURN AND UPPER
LEVEL ENERGY. KEPT A CHANCE FOR THUNDER ACROSS THE SOUTHERN
FA...BUT CONFIDENCE NOT HIGH. TEMPERATURES AGAIN CLIMB TO ABOVE
NORMAL VALUES.
SUNDAY NIGHT-THURSDAY...UPPER RIDGING AND PERSISTENT LOW-LEVEL
SOUTHERLY FLOW WILL STILL KEEP WARM AND HUMID AIR IN PLACE FOR THE
FIRST DAY OF THE EXTENDED PERIOD...WITH HIGHS WELL UP IN THE 80S.
STRONG UPPER WAVE LIFTING FROM PAC NW TO SOUTHERN CANADA WILL
CLOSE OFF...WITH AN ANOMALOUSLY DEEP SURFACE LOW INDICATED
NORTHERN HIGH PLAINS BY MON NIGHT INTO TUESDAY. STACKED LOW WILL
BE NEARLY STATIONARY WEST OF THE FORECAST AREA WHILE SEVERAL
BOUNDARIES MOVE TO THE EAST OVER NORTHERN PLAINS AND INTO
MINNESOTA TUE/WED WITH CHC POPS PREVAILING. THE COMPLEX IS LIKELY
TO MOVE THROUGH THE REGION WED NIGHT INTO THURS ACCOMPANIED BY A
GUSTY WIND SHIFT TO NW AND A DRIER REGIME TO END THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM CDT THU JUL 23 2015
GUSTY SSE WINDS TO DIMINISH ARD SUNSET AS A LINE OF THUNDERSTORMS
PROGRESSES FROM WEST TO EAST TOWARD DEVILS LK BASIN. TEMPO FOR TSRA
INCLUDED FROM MID EVENING THROUGH OVERNIGHT FROM KDVL THROUGH VALLEY
SITES. WIND SHIFT TO NW WILL OCCUR BEHIND BOUNDARY FROM LATE NIGHT
INTO EARLY FRI MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...WJB/TG
AVIATION...WJB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1135 PM CDT WED JUL 22 2015
.UPDATE...
ISSUED AT 1135 PM CDT WED JUL 22 2015
A COUPLE OF CELLS HAVE FORMED UP AROUND KBDE BUT HAVE JUST ABOUT
MOVED OUT OF THE AREA. LATEST RAP HINTS AT SOME ACTIVITY UP IN
THIS AREA OVERNIGHT...BUT NOT CONVINCED MUCH WILL HAPPEN AT THIS
POINT. THEREFORE WILL MAINTAIN A DRY FORECAST FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 350 PM CDT WED JUL 22 2015
UPPER LEVEL RIDGE EXTENDED FROM THE HIGH PLAINS OF WY TO NORTHERN
MAN. UPPER LEVEL RIDGE WILL BUILD AND SHIFT EAST TONIGHT AND THU.
WATER VAPOR LOOP INDICATED A WEAK SHORT WAVE OVER WESTERN ND AND WAS
MOVING EAST ABOUT 30 KNOTS. MD LEVEL LAPSE RATES WERE MODEST OVER
ALL BUT THE NORTHEAST ZONES THIS AFTERNOON. LOW THREAT FOR PRECIP
OVER AREA WITH MODEST LAPSE RATES. MODEST LAPSE RATE AREA TO SHIFT
NORTHEAST OVERNIGHT AND WILL KEEP LOW POPS THERE.
CAPES FORECAST AROUND 2000-2500 J/KG AND CIN WERE UNDER 50 J/KG FOR
THU AFTERNOON/EVENING. CONVECTIVE TEMPS WERE RATHER HIGH WITH A WEAK
INVERSION AROUND 750 HPA. WARM 700 HPA TEMPS EXPECTED TO CAP
ATMOSPHERE PRE-FRONTALLY. SURFACE TROUGH TO MOVE INTO THE AREA LATE
AFTERNOON/EVENING THU SHOULD TRIGGER THUNDERSTORMS.
NEXT CHANCE FOR DIURNALLY DRIVEN THUNDERSTORMS WOULD BE SAT
AFTERNOON AND EVENING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 350 PM CDT WED JUL 22 2015
(SUNDAY-WEDNESDAY)...THERE IS A RATHER CONSISTENT SIGNAL
IN ALL EXTENDED GUIDANCE INDICATING A STRONG SYSTEM ACROSS SOUTHERN
CANADA THAT WILL SEND A COLD FRONT THROUGH THE REGION ON MONDAY.
ALTHOUGH CONFIDENCE IN DETAILS WILL REMAIN LOW...THERE DOES APPEAR A
HIGHER LIKELIHOOD FOR SEVERE THUNDERSTORMS WITH THIS FROPA. ABOVE
NORMAL TEMPERATURES TO BEGIN THE PERIOD WILL TRANSITION TO NEAR
NORMAL VALUES BY MID-WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1135 PM CDT WED JUL 22 2015
ALL TAF SITES ARE SEEING STEADY SSE WINDS NOW WITH GENERALLY
CLEAR SKIES. WARM MID LEVEL TEMPS BUILD INTO THE AREA DURING THE
DAY THU SO NOT EXPECTING MUCH OTHER THAN A BIT OF CIRRUS. COLD
FRONT EXPECTED TO MOVE INTO THE KDVL REGION AROUND 00Z FRI...WHICH
WILL START SOME TSTMS MOVING EASTWARD. THREW IN A MENTION AT
KGFK/KFAR AROUND 05Z FRI...BUT THIS IS JUST A BALLPARK TIME AT
THIS POINT. COULD BE A LITTLE SOONER OR LATER. NOT EXPECTING ANY
TSTMS AT KTVF/KBJI UNTIL AFTER THIS TAF PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GODON
SHORT TERM...HOPPES
LONG TERM...TG
AVIATION...GODON
AREA FORECAST DISCUSSION
NWS TULSA OK
908 PM CDT FRI JUL 24 2015
...UPDATE...
.DISCUSSION...
AREA OF THUNDERSTORMS OVER SOUTH CENTRAL MISSOURI WILL MAKE A
CLOSE APPROACH TO PARTS OF FAR NORTHWEST ARKANSAS...BUT WITH
RECENT RADAR TRENDS INDICATING A DISSIPATING TREND ON THE
NORTHWEST EDGE NEAR SPRINGFIELD AND ALSO WARMING CLOUD TOPS IN
SATELLITE IMAGERY...CURRENT THINKING IS THAT THE STORMS WILL MISS
THE FORECAST AREA ENTIRELY. THIS IS FAIRLY WELL DEPICTED IN THE
LATEST HRRR GUIDANCE AS WELL. FOR THESE REASONS...WILL NOT PUT ANY
MENTIONABLE POPS IN THE ONGOING FORECAST.
OVERALL...THE FORECAST LOOKS WELL IN HAND...WITH OVERNIGHT LOWS
BEING VERY NEAR LAST NIGHTS. EARLIER UPDATE ADDRESSED THE
EXPIRATION OF THE AFTERNOON HEAT HEADLINES...AND NO FURTHER UPDATE
IS PLANNED AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 600 PM CDT FRI JUL 24 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 0Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL SITES THROUGHOUT
THE 24 HOUR FORECAST PERIOD.
PREV DISCUSSION... /ISSUED 352 PM CDT FRI JUL 24 2015/
DISCUSSION...
A RIDGE OF HIGH PRESSURE REMAINS THE DOMINATE FEATURE ACROSS THE
SOUTHERN PLAINS THIS AFTERNOON. THIS HAS ALLOWED FOR SOUTH TO
SOUTHWESTERLY LOW LEVEL FLOW TO TRANSPORT HOT TEMPERATURES ON TOP
OF DEWPOINTS IN THE 70S ACROSS MUCH OF EASTERN OKLAHOMA AND
NORTHEAST ARKANSAS. THE RESULTS ARE MOSTLY SUNNY SKIES...HOT AND
HUMID CONDITIONS AND HEAT INDICES AROUND 105 DEGREES TO AROUND
112 DEGREES OVER THE CWA. THUS...WILL LET THE CURRENT HEAT
HEADLINES RIDE AS IS THROUGH MID EVENING.
THE RIDGE REMAINS INTACT OVER THE SOUTHERN PLAINS THROUGH THE
WEEKEND AND INTO THE FIRST HALF OF NEXT WEEK. THE CENTER OF THE
HIGH PRESSURE LOOKS TO OSCILLATE A BIT FROM WEST TO EAST AND BACK
THROUGH TUESDAY OF NEXT WEEK...WHICH COULD ALLOW FOR A DIFFERENCE
OF A DEGREE OR SO IN SURFACE TEMPS EACH DAY. HOWEVER...WITH 850-MB
IN THE LOW TO MID +20C RANGE...HIGH TEMPS IN THE MID 90S FOR FAR
NORTHWEST ARKANSAS TO THE UPPER 90S/NEAR 100 DEGREES WILL REMAIN
COMMON ELSEWHERE OVER THE CWA THROUGH TUESDAY. THUS...HAVE
EXTENDED THE HEAT ADVISORY INTO SATURDAY AFTERNOON FOR MOST
LOCATIONS AND WILL PROBABLY HAVE TO EXTEND AGAIN FOR SUNDAY AND
MONDAY. HEAT INDICES OF AROUND 105 TO 110 DEGREES ARE FORECAST.
IN THE EXTENDED FORECAST...THE RIDGE OF HIGH PRESSURE LOOKS TO
FINALLY SHIFT FAR ENOUGH WEST FOR THE SECOND HALF OF NEXT WEEK TO
ALLOW FOR NORTHWESTERLY FLOW TO RETURN OVER THE PLAINS. THIS COULD
ALLOW FOR A WAVE...FORECAST TO MOVE INTO THE PACIFIC NORTHWEST
THIS WEEKEND...TO DROP A FRONTAL BOUNDARY AND RAIN CHANCES INTO
THE REGION THURSDAY/FRIDAY OF NEXT WEEK. THIS COULD BRING A BRIEF
RELIEF FROM THE HOT AND HUMID CONDITIONS...THOUGH WE WILL JUST
HAVE TO WAIT AND SEE...
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY FROM NOON TO 8 PM CDT SATURDAY FOR OKZ049-053>076.
AR...HEAT ADVISORY FROM NOON TO 8 PM CDT SATURDAY FOR ARZ001-002-019-
020-029.
&&
$$
SHORT TERM...22
AREA FORECAST DISCUSSION
NWS NORMAN OK
328 PM CDT THU JUL 23 2015
.DISCUSSION...
WITH AN UPPER LEVEL RIDGE FIRMLY IN PLACE...THIS FORECAST
DISCUSSION WILL BE LEFT FAIRLY DRY.
ONLY CHALLENGE AT THE MOMENT WILL BE THE CHANCE OF A FEW SHOWERS
OR THUNDERSTORMS CLIPPING FAR NORTH CENTRAL OK LATER THIS
EVENING/OVERNIGHT AS A WEAK COMPLEX OF STORMS MAY MAINTAIN AND
SLIDE S/SE ACROSS CENTRAL KS. CONFIDENCE IS LOW AT THE MOMENT
GIVEN AS THE VAST MAJORITY OF SHORT RANGE GUIDANCE IS NOT TOO KEEN
ON DEVELOPING PRECIP. THE HRRR IS THE OUTLIER... BUT GIVEN ITS
OVER CONVECTIVE NATURE WITH OUR WEAK FORCING REGIME... DO NOT FEEL
CONFIDENT AT THE MOMENT TO PLACE ANY MENTION IN THE FORECAST.
HEAT IS THE BIG STORY GOING INTO THE WEEKEND AS TEMPERATURES NEAR
100 DEGREES AND HEAT INDICES NEAR 105 DEGREES. A HEAT ADVISORY IS
IN EFFECT FOR EASTERN PARTS OF THE CWA FOR FRIDAY...AND FUTURE
HEAT ADVISORIES MAY BE NEEDED THROUGH THE WEEKEND.
BY MID WEEK NEXT WEEK...A TROUGH TRIES TO MOVE THROUGH...WEAKENING
THE RIDGE JUST ENOUGH TO BRING IN SLIGHT CHANCE POPS AND COOL
TEMPERATURES BY A FEW DEGREES.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 76 98 75 98 / 0 0 0 0
HOBART OK 77 102 75 101 / 0 0 0 0
WICHITA FALLS TX 78 100 77 100 / 0 0 0 0
GAGE OK 74 101 73 100 / 0 10 10 10
PONCA CITY OK 77 100 77 100 / 0 0 0 0
DURANT OK 77 99 76 100 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR OKZ006>008-011>013-
017>020-024>026-029>032-042-043-047-048-051-052.
HEAT ADVISORY FROM 1 PM TO 8 PM CDT FRIDAY FOR OKZ005>008-
011>013-017>020-024>026-029>032-042-043-047-048-051-052.
TX...NONE.
&&
$$
MAD/JTK
AREA FORECAST DISCUSSION
NWS NORMAN OK
1244 PM CDT THU JUL 23 2015
.DISCUSSION...
THE 18Z TAF DISCUSSION IS BELOW.
&&
.AVIATION...
ISOLATED STORMS WILL CONTINUE TO AFFECT KPNC THROUGH ABOUT 19Z.
OTHERWISE...A RIDGE ALOFT WILL KEEP CLOUDS MINIMAL THROUGH THE TAF
PERIOD. WINDS WILL FOLLOW A NORMAL DIURNAL PATTERN.
MAHALE
&&
.PREV DISCUSSION... /ISSUED 435 AM CDT THU JUL 23 2015/
DISCUSSION...
THE STORMS THIS MORNING SHOULD BE ONE LAST HOORAH FOR CONVECTION
FOR A FEW DAYS. STORMS WILL AT LEAST PERSIST ACROSS NORTH CENTRAL
OKLAHOMA WHILE THE HRRR AND RAP SHOW THE CHANCE OF STORMS
DEVELOPING FARTHER SOUTH AS WELL. DID EXPAND THE SLIGHT CHANCE
POPS FARTHER SOUTH GIVEN THE HRRR AND RAP SIGNAL. EXPECT STORMS TO
HAVE MOVED EAST OF THE AREA AND/OR DISSIPATED BY EARLY THIS
AFTERNOON.
FOCUS REMAINS ON HEAT OVER THE NEXT FEW DAYS. GFS INITIALIZED
DEWPOINTS WAY TOO LOW THIS MORNING OVER THE AREA SO BLENDED WENT
WELL ABOVE BLENDED INITIALIZATION FOR DEWPOINTS. TEMPERATURES WILL
BE HIGH THIS AFTERNOON ALTHOUGH NOT CRAZY HIGH... BUT DEWPOINTS
EXPECTED TO REMAIN IN THE LOW TO MID 70S WILL BRING HEAT INDEX
VALUES OVER 110 IN SOME AREAS. HAVE ISSUED A HEAT ADVISORY FOR THE
NORTH CENTRAL... CENTRAL AND SOUTHEAST FOR THIS AFTERNOON. HEAT
WILL CONTINUE TO BE THE PRIMARY WEATHER STORY OVER THE NEXT FEW
DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 96 75 98 75 / 20 0 0 0
HOBART OK 100 76 102 75 / 10 10 0 0
WICHITA FALLS TX 99 77 100 77 / 10 10 0 0
GAGE OK 99 73 100 73 / 10 10 10 10
PONCA CITY OK 95 77 99 77 / 40 10 0 0
DURANT OK 98 77 99 76 / 10 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR OKZ006>008-011>013-
017>020-024>026-029>032-042-043-047-048-051-052.
TX...NONE.
&&
$$
23/04/10
AREA FORECAST DISCUSSION
NWS NORMAN OK
435 AM CDT THU JUL 23 2015
.DISCUSSION...
THE STORMS THIS MORNING SHOULD BE ONE LAST HOORAH FOR CONVECTION
FOR A FEW DAYS. STORMS WILL AT LEAST PERSIST ACROSS NORTH CENTRAL
OKLAHOMA WHILE THE HRRR AND RAP SHOW THE CHANCE OF STORMS
DEVELOPING FARTHER SOUTH AS WELL. DID EXPAND THE SLIGHT CHANCE
POPS FARTHER SOUTH GIVEN THE HRRR AND RAP SIGNAL. EXPECT STORMS TO
HAVE MOVED EAST OF THE AREA AND/OR DISSIPATED BY EARLY THIS
AFTERNOON.
FOCUS REMAINS ON HEAT OVER THE NEXT FEW DAYS. GFS INITIALIZED
DEWPOINTS WAY TOO LOW THIS MORNING OVER THE AREA SO BLENDED WENT
WELL ABOVE BLENDED INITIALIZATION FOR DEWPOINTS. TEMPERATURES WILL
BE HIGH THIS AFTERNOON ALTHOUGH NOT CRAZY HIGH... BUT DEWPOINTS
EXPECTED TO REMAIN IN THE LOW TO MID 70S WILL BRING HEAT INDEX
VALUES OVER 110 IN SOME AREAS. HAVE ISSUED A HEAT ADVISORY FOR THE
NORTH CENTRAL... CENTRAL AND SOUTHEAST FOR THIS AFTERNOON. HEAT
WILL CONTINUE TO BE THE PRIMARY WEATHER STORY OVER THE NEXT FEW
DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 96 75 98 75 / 20 0 0 0
HOBART OK 100 76 102 75 / 10 10 0 0
WICHITA FALLS TX 99 77 100 77 / 10 10 0 0
GAGE OK 99 73 100 73 / 10 10 10 10
PONCA CITY OK 95 77 99 77 / 40 10 0 0
DURANT OK 98 77 99 76 / 10 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING
FOR OKZ006>008-011>013-017>020-024>026-029>032-042-043-047-
048-051-052.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
845 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 845 PM CDT FRI JUL 24 2015
SOME ELEVATED CONVECTION ALREADY DEVELOPING OUT WEST THIS EVENING
AND MOVING EAST. EXPECT THIS DEVELOPMENT TO CONTINUE THROUGH THE
NIGHT AS SHOWN BY THE HRRR MODEL. IT SHOULD REMAIN WEST OF THE
JAMES RIVER VALLEY. ADJUSTED WEATHER AND POPS FOR THE NIGHT.
UPDATE ISSUED AT 624 PM CDT FRI JUL 24 2015
00Z AVIATION DISCUSSION UPDATED BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 247 PM CDT FRI JUL 24 2015
THERE ARE A NUMBER OF FORECAST CHALLENGES IN THE SHORT TERM
REGARDING THUNDERSTORM CHANCES AND SEVERE POTENTIAL. MODELS ARE IN
GENERAL AGREEMENT ON THE OVERALL SYNOPTIC PATTERN BUT THERE ARE SOME
SIGNIFICANT DIFFERENCES IN PLACEMENT/TIMING ON THE NEW 12Z RUNS
BETWEEN THE HI-RES CAMS AND THE GLOBAL MODELS. THE ECMWF IS ALSO
FARTHER SOUTH THAN PREVIOUS SOLUTIONS WHILE THE GFS ENHANCED THE
EASTERN H5 SHORTWAVE SAT EVENING AND THEREFORE KEEPS A RATHER ROBUST
QPF FIELD ACROSS THE EASTERN CWA.
STUCK WITH THE HI-RES SOLUTIONS THIS EVENING WHICH GENERATE SOME
STORMS WEST RIVER BY 0Z. WHILE CAPE IS UNDERWHELMING..LESS THAN 1000
J/KG ON THE RAP...UNTIL CLOSE TO 12Z SAT SHEAR IS AROUND 45 TO 55
KTS AND CIN IS MINIMAL. THESE STORMS WILL NOT MIGRATE VERY FAR EAST
UNTIL CLOSER TO MORNING. ANY LEFT OVER CLOUDINESS MAY HAMPER INITIAL
RE-DEVELOPMENT SAT AFTERNOON AS A STRONG SHORTWAVE BEGINS TO MOVE
FROM WEST TO EAST ACROSS THE SOUTHERN CWA. SHEAR IN THE BAROCLINIC
ZONE WILL BE SUFFICIENT FOR ANY STORMS THAT DO DEVELOP TO BECOME
SEVERE.
MOST OF THE DAY SUNDAY WILL BE DRY IN BETWEEN SYSTEMS. THERE IS AN
APPROACHING SFC LOW AND SOME WEAKER SHORTWAVE ENERGY SUNDAY EVENING
THAT MAY FIRE OFF A FEW STORMS BUT MODELS DIVERGE GREATLY ON
PLACEMENT WITH SOME KEEPING ANY PRECIP CHANCE OUT OF THIS CWA.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 247 PM CDT FRI JUL 24 2015
SLIGHT PRECIP CHANCES REMAIN IN THE FORECAST FOR EARLY IN THE
WORKWEEK AS AN UPPER LEVEL TROUGH MOVES OUT OF THE PACIFIC
NORTHWEST...ALTHOUGH 700 MB TEMPERATURES RANGING FROM 12 C TO 16 C
WILL KEEP A CAP ON MOST CONVECTION. NORTHWEST FLOW BEHIND THE TROUGH
WILL THEN BRING COOLER AND DRIER CONDITIONS BY MID WEEK...AS WELL AS
GUSTY WINDS. THIS WILL BE SHORT LIVED HOWEVER...AS 500 MB HEIGHTS
ARE ON THE RISE BY THE END OF THE WORKWEEK...WITH FORECAST MAX
TEMPERATURES BACK IN THE UPPER 80S AND 90S BY FRIDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 624 PM CDT FRI JUL 24 2015
VFR CONDITIONS ARE EXPECTED AT ALL LOCATIONS THROUGH TONIGHT AND
SATURDAY. A COUPLE ROUNDS OF THUNDERSTORMS ARE EXPECTED INTO
SATURDAY AFTERNOON. THE FIRST ROUND OF STORMS WERE DEVELOPING EARLY
THIS EVENING OUT WEST AND ARE EXPECTED TO MOVE INTO CENTRAL SD LATER
THIS EVENING AND OVERNIGHT. AT THIS TIME...PIR AND MAYBE MBG COULD
BE AFFECTED. THE NEXT ROUND WILL COME SATURDAY AFTERNOON AND COULD
POSSIBLY AFFECT ALL LOCATIONS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...WISE
LONG TERM...SERR
AVIATION...MOHR
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
229 PM MDT THU JUL 23 2015
.SHORT TERM...THIS EVENING THROUGH FRIDAY NIGHT
ISSUED AT 227 PM MDT THU JUL 23 2015
UPPER LEVEL ANALYSIS HAS A BROAD AREA OF HIGH PRESSURE OVER THE
SOUTHERN PLAINS WITH A SHORTWAVE TROF OVER THE PACIFIC NORTHWEST.
WATER VAPOR IMAGERY SHOWS A SHORTWAVE PUSHING INTO SOUTHERN
MONTANA WITH SOUTHWEST FLOW ACROSS THE NORTHERN PLAINS. AT THE
SURFACE...THERE IS AN AREA OF LOW PRESSURE OVER THE WESTERN DAKOTA
WITH A WEAK COLD FRONT EXTENDING THROUGH FAR NORTHWESTERN SOUTH
DAKOTA AND NORTHERN WYOMING. AHEAD OF THE COLD FRONT A TROF/DRY
LINE EXTENDS THROUGH SOUTH CENTRAL SOUTH DAKOTA INTO CENTRAL
NEBRASKA. TEMPERATURES AT 2 PM RANGED FROM THE MID 80S OVER THE
BLACK HILLS TO THE UPPER 90S IN SOUTH CENTRAL SOUTH DAKOTA.
THE DRY LINE IN SOUTH CENTRAL SOUTH DAKOTA WILL BE THE FOCUS FOR
STORMS THIS AFTERNOON INTO EARLY EVENING. AS THE DRY LINE SHIFTS
EAST...ANY STORMS THAT FORM SHOULD QUICKLY PUSH OUT OF THE FORECAST
AREA.
THE WESTERN TROF WILL BEGIN TO LIFT NORTH TONIGHT AS THE COLD FRONT
SLOWLY PUSHES THOUGH WESTERN SOUTH DAKOTA. SHEAR IS WEAK...VALUES OF
15KTS OR LESS AND CAPE IS MINIMAL. SHORT RANGE MODELS VARY WITH
RESPECT TO POPS TONIGHT WITH RAP SHOWING DRY CONDITIONS...HRRR
SHOWING SOME ISOLATED TO SCATTERED CONVECTION OVER NORTHEASTERN
WYOMING AND NORTHWESTERN SOUTH DAKOTA AND SDSMT WRF INDICATING
ISOLATED CONVECTION JUST NORTH OF THE HILLS. DUE TO THE MODEL
DIFFERENCES...HAVE DECIDED TO KEEP LOW POPS IN THE FORECAST TONIGHT.
TEMPERATURES OVERNIGHT WILL FALL INTO THE UPPER 50S BEHIND THE
FRONT...WITH 60S TO LOWER 70S AHEAD OF THE FRONT IN SOUTH CENTRAL
SOUTH DAKOTA.
ON FRIDAY...BROAD RIDGE REMAINS ANCHORED ACROSS THE SOUTHERN PLAINS
WITH WESTERLY UPPER FLOW ALOFT OVER THE NORTHERN PLAINS. SURFACE
HIGH PRESSURE WILL MOVE EASTERLY ACROSS THE DAKOTAS EARLY IN THE
DAY...WITH SOUTHERLY RETURN FLOW BY LATE AFTERNOON. A WEAK UPPER
LEVEL SHORTWAVE WILL CROSS THE AREA DURING THE AFTERNOON AND
EVENING...BRINGING A CHANCE FOR SOME SHOWERS AND THUNDERSTORMS. HIGH
TEMPERATURES WILL BE SLIGHTLY COOLER THAN TODAY...IN THE 80S TO
LOWER 90S. LOW TEMPERATURES FRIDAY NIGHT WILL BE IN THE MID 50S TO
UPPER 60S.
.LONG TERM...SATURDAY THROUGH THURSDAY
ISSUED AT 227 PM MDT THU JUL 23 2015
ZONAL FLOW IS EXPECTED THROUGH THE END OF THE WEEKEND...WITH
SUBTLE WAVES BRINGING DAILY ISOLATED STORMS TO DIFFERING PORTIONS
OF THE AREA. UPPER TROUGH IS PROGGED TO DEVELOP ACROSS THE NW PAC
COAST SUNDAY...THEN MOVE ACROSS THE NRN PLAINS/SRN CANADA MONDAY
INTO TUESDAY. GOOD AGREEMENT BETWEEN GFS/ECM SHOWING STORMS
DEVELOPING ALONG A COLD FRONT SOUTH OF THE SURFACE LOW. COOLER AND
DRIER AIR WILL PUSH IN BEHIND THE FRONT AND REMAIN FOR THE REST OF
THE LONG TERM. TEMPS WILL STILL BE NEAR TO SLIGHTLY BELOW AVERAGE.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z FRIDAY
ISSUED AT 227 PM MDT THU JUL 23 2015
A FEW STORMS COULD INITIATE ALONG A COLD FRONT IN FAR NORTHWESTERN
SD AND NORTHEASTERN WY THIS AFTERNOON. OTHERWISE, VFR CONDITIONS
SHOULD PERSIST. WINDS WILL SHIFT FROM SOUTHWEST TO NORTHWEST AND
BE GUSTY AT TIMES PRIOR TO SUNSET.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...MLS
LONG TERM...13
AVIATION...WARD
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1249 PM CDT THU JUL 23 2015
.DISCUSSION...
UPDATED FOR 18Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 1114 AM CDT THU JUL 23 2015/
UPDATE...
STALLED FRONT REMAINS DRAPED ACROSS THE AREA FROM NEAR JONESBORO
TO NEAR SAVANNAH. SHOWERS AND THUNDERSTORMS WILL REDEVELOP ALONG
THE BOUNDARY THIS AFTERNOON. LATEST HRRR SHOWS MOST OF THE
REDEVELOPMENT MAY OCCUR ALONG AND SOUTH OF A JONESBORO TO
SAVANNAH LINE MAINLY DURING THE 3 PM-7 PM CDT TIME FRAME.
MEANWHILE...ONGOING CONVECTION ACROSS NE ARKANSAS WILL PUSH EAST
INTO THE MO BOOTHEEL AND NORTHWEST TENNESSEE DURING THE EARLY
AFTERNOON HOURS WHILE CONVECTION NEAR THE TENNESSEE RIVER WILL
PUSH EAST INTO MIDDLE TENNESSEE OVER THE NEXT 1-2 HOURS. WILL
MAKE MINOR TWEAKS TO POPS...OTHERWISE REST OF FORECAST LOOKS
GOOD.
KRM
DISCUSSION... /ISSUED 319 AM CDT THU JUL 23 2015/
CURRENTLY THE MIDSOUTH WAS CLOUDY TO MOSTLY CLOUDY. SCATTERED
SHOWERS AND STORMS WERE DOTTED MAINLY NORTH OF INTERSTATE FORTY AS
OF 3 AM. TEMPERATURES WERE VERY SIMILAR TO THIS TIME LAST NIGHT
WITH WIDESPREAD LOW TO MID 70S. WINDS WERE GENERALLY CALM OVER THE
EASTERN COUNTIES...WITH SOUTH WINDS OF 3 TO 8 KTS ALONG AND WEST
OF THE MISSISSIPPI RIVER.
FOR TODAY AND TONIGHT...NOT MUCH CHANGE TAKING PLACE IN THE
ATMOSPHERE THE NEXT 24 HOURS...AND NOT MUCH CHANGE IN THE MODEL
OUTPUTS SINCE YESTERDAY. THE STORM TRACK WILL CONTINUE TO RIDE
ALONG A STALLED FRONTAL BOUNDARY WITH CURRENT WATER VAPOR IMAGERY
AND RADAR SHOWING DISTURBANCES LINED UP BACK INTO THE CENTRAL
PLAINS. THE UPPER RIDGE IS BUILDING OVER THE FRONT RANGE WHICH THE
MODELS HAVE SHOWN...AND AS A RESULT 500MB WINDS HAVE VEERED
NORTHWESTERLY ACROSS NORTHERN OKLAHOMA. ON THE SURFACE CURRENT
WEAK FRONT HAS PUSHED A LITTLE NORTH DURING THE PAST 24
HOURS...NOW RIDING ALONG THE KY/TN BORDER.
MUCH OF THE MIDSOUTH WILL SEE SCATTERED SHOWERS AND STORMS
TODAY...WITH SOME HAVING THE POTENTIAL TO BE STRONG OR SEVERE.
PLAN ON A MARGINAL RISK MENTION IN THIS MORNINGS HWO. ACTIVITY IS
EXPECTED TO BEGIN DECREASING TONIGHT OVER THE NORTH AS THE
DEVELOPING NORTHWEST GIVES THE FRONT A PUSH TO THE SOUTH. HAVE
EXTENDED THE FFA OVER NORTHEAST ARKANSAS AND THE BOOTHEEL OF
MISSOURI THROUGH EARLY THIS EVENING TO CAPTURE THIS PASSAGE.
HIGHS WILL RANGE FROM THE UPPER 80S...TO LOW 90S.
TOMORROW...THE ENTIRE REGION WILL BE BACK IN NORTHWEST FLOW ALOFT
WITH THE WEAK FRONT STALLING ACROSS THE FAR SOUTHWEST COUNTIES.
IT APPEARS THAT JUST ENOUGH STABLE AIR FROM THE OHIO VALLEY MAY
WORKS ITS WAY INTO THE FAR NORTHEAST COUNTIES...TAKING RAIN
CHANCES TO BELOW 15 PERCENT. DEWPOINTS IN THIS REGION WILL ALSO FALL
INTO 60S. ELSEWHERE THE HUMIDITY WILL STILL REMAIN HIGH FRO
ISOLATED CONVECTION...AND THE SOUTHWEST COUNTIES MAY FLIRT WITH
HEAT ADVISORY CONDITIONS.
SATURDAY THROUGH MONDAY...THE RETURN TO HIGHER HEAT IS STILL WELL
ON TRACK...WITH MINIMAL RAIN CHANCES. HIGH PRESSURE THROUGHOUT
THE COLUMN WILL YIELD LIGHT WINDS AND STRONG SUBSIDENCE. WIDESPREAD
MID AND UPPER 90 TEMPERATURES ARE ANTICIPATED WITH HEAT ADVISORIES
LIKELY.
TUESDAY AND WEDNESDAY...A STRONG SHORTWAVE WILL ENTER THE NORTHERN
ROCKIES NEXT WEEK BEFORE TRACKING INTO THE UPPER MIDWEST. THE
RIDGE WILL FLATTEN SOME OVER THE MIDSOUTH...BUT MODELS ARE NOT
REALLY SIGNALING A CHANGE IN TEMPERATURES. AN ISOLATED SHOWER
DURING THE PERIOD MAY COOL A FEW OFF OTHERWISE CONFIDENCE IS HIGH
THAT HEAT INDICES ABOVE 105F WILL CONTINUE.
JAB
&&
.AVIATION...
18Z TAF CYCLE
A WEAK FRONT REMAINS ACROSS THE AREA. SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP INVOF THIS
BOUNDARY INTO THIS EVENING. IN THE SHORT TERM...KMEM STANDS THE
BEST CHANCE OF TSRAS ON STATION OVER THE NEXT 1-2 HOURS. ELSW
WILL CONTINUE A MENTION OF VCTS THROUGH ABOUT 24/01Z AREAWIDE.
OUTSIDE OF SHRAS/TSRAS EXPECT VFR CONDS. AREAS OF FOG DEVELOPING
AFTER 24/06Z WITH MVFR CONDITIONS POSSIBLE AT KMEM...KJBR AND
KTUP...IFR CONDITIONS POSSIBLE AT KMKL. WINDS WEST THIS AFTERNOON
6-8 KTS AND LIGHT TONIGHT INTO FRIDAY MORNING.
SJM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-MISSISSIPPI-POINSETT-
RANDOLPH-ST. FRANCIS.
MO...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR DUNKLIN-
PEMISCOT.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1114 AM CDT THU JUL 23 2015
.UPDATE...
STALLED FRONT REMAINS DRAPED ACROSS THE AREA FROM NEAR JONESBORO
TO NEAR SAVANNAH. SHOWERS AND THUNDERSTORMS WILL REDEVELOP ALONG
THE BOUNDARY THIS AFTERNOON. LATEST HRRR SHOWS MOST OF THE
REDEVELOPMENT MAY OCCUR ALONG AND SOUTH OF A JONESBORO TO
SAVANNAH LINE MAINLY DURING THE 3 PM-7 PM CDT TIME FRAME.
MEANWHILE...ONGOING CONVECTION ACROSS NE ARKANSAS WILL PUSH EAST
INTO THE MO BOOTHEEL AND NORTHWEST TENNESSEE DURING THE EARLY
AFTERNOON HOURS WHILE CONVECTION NEAR THE TENNESSEE RIVER WILL
PUSH EAST INTO MIDDLE TENNESSEE OVER THE NEXT 1-2 HOURS. WILL
MAKE MINOR TWEAKS TO POPS...OTHERWISE REST OF FORECAST LOOKS
GOOD.
KRM
&&
.DISCUSSION... /ISSUED 319 AM CDT THU JUL 23 2015/
CURRENTLY THE MIDSOUTH WAS CLOUDY TO MOSTLY CLOUDY. SCATTERED
SHOWERS AND STORMS WERE DOTTED MAINLY NORTH OF INTERSTATE FORTY AS
OF 3 AM. TEMPERATURES WERE VERY SIMILAR TO THIS TIME LAST NIGHT
WITH WIDESPREAD LOW TO MID 70S. WINDS WERE GENERALLY CALM OVER THE
EASTERN COUNTIES...WITH SOUTH WINDS OF 3 TO 8 KTS ALONG AND WEST
OF THE MISSISSIPPI RIVER.
FOR TODAY AND TONIGHT...NOT MUCH CHANGE TAKING PLACE IN THE
ATMOSPHERE THE NEXT 24 HOURS...AND NOT MUCH CHANGE IN THE MODEL
OUTPUTS SINCE YESTERDAY. THE STORM TRACK WILL CONTINUE TO RIDE
ALONG A STALLED FRONTAL BOUNDARY WITH CURRENT WATER VAPOR IMAGERY
AND RADAR SHOWING DISTURBANCES LINED UP BACK INTO THE CENTRAL
PLAINS. THE UPPER RIDGE IS BUILDING OVER THE FRONT RANGE WHICH THE
MODELS HAVE SHOWN...AND AS A RESULT 500MB WINDS HAVE VEERED
NORTHWESTERLY ACROSS NORTHERN OKLAHOMA. ON THE SURFACE CURRENT
WEAK FRONT HAS PUSHED A LITTLE NORTH DURING THE PAST 24
HOURS...NOW RIDING ALONG THE KY/TN BORDER.
MUCH OF THE MIDSOUTH WILL SEE SCATTERED SHOWERS AND STORMS
TODAY...WITH SOME HAVING THE POTENTIAL TO BE STRONG OR SEVERE.
PLAN ON A MARGINAL RISK MENTION IN THIS MORNINGS HWO. ACTIVITY IS
EXPECTED TO BEGIN DECREASING TONIGHT OVER THE NORTH AS THE
DEVELOPING NORTHWEST GIVES THE FRONT A PUSH TO THE SOUTH. HAVE
EXTENDED THE FFA OVER NORTHEAST ARKANSAS AND THE BOOTHEEL OF
MISSOURI THROUGH EARLY THIS EVENING TO CAPTURE THIS PASSAGE.
HIGHS WILL RANGE FROM THE UPPER 80S...TO LOW 90S.
TOMORROW...THE ENTIRE REGION WILL BE BACK IN NORTHWEST FLOW ALOFT
WITH THE WEAK FRONT STALLING ACROSS THE FAR SOUTHWEST COUNTIES.
IT APPEARS THAT JUST ENOUGH STABLE AIR FROM THE OHIO VALLEY MAY
WORKS ITS WAY INTO THE FAR NORTHEAST COUNTIES...TAKING RAIN
CHANCES TO BELOW 15 PERCENT. DEWPOINTS IN THIS REGION WILL ALSO FALL
INTO 60S. ELSEWHERE THE HUMIDITY WILL STILL REMAIN HIGH FRO
ISOLATED CONVECTION...AND THE SOUTHWEST COUNTIES MAY FLIRT WITH
HEAT ADVISORY CONDITIONS.
SATURDAY THROUGH MONDAY...THE RETURN TO HIGHER HEAT IS STILL WELL
ON TRACK...WITH MINIMAL RAIN CHANCES. HIGH PRESSURE THROUGHOUT
THE COLUMN WILL YIELD LIGHT WINDS AND STRONG SUBSIDENCE. WIDESPREAD
MID AND UPPER 90 TEMPERATURES ARE ANTICIPATED WITH HEAT ADVISORIES
LIKELY.
TUESDAY AND WEDNESDAY...A STRONG SHORTWAVE WILL ENTER THE NORTHERN
ROCKIES NEXT WEEK BEFORE TRACKING INTO THE UPPER MIDWEST. THE
RIDGE WILL FLATTEN SOME OVER THE MIDSOUTH...BUT MODELS ARE NOT
REALLY SIGNALING A CHANGE IN TEMPERATURES. AN ISOLATED SHOWER
DURING THE PERIOD MAY COOL A FEW OFF OTHERWISE CONFIDENCE IS HIGH
THAT HEAT INDICES ABOVE 105F WILL CONTINUE.
JAB
&&
.AVIATION...
12Z TAF CYCLE (23/12Z-24/12Z)
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS
THE MIDSOUTH TODAY INTO THIS EVENING AS WEAK UPPER LEVEL
DISTURBANCES INTERACT WITH A MOIST AND UNSTABLE ATMOSPHERE. TIMING
AND PLACEMENT OF THE CONVECTION IS DIFFICULT BEYOND A FEW HOURS. VFR
CONDITIONS WILL PREVAIL OUTSIDE SHOWERS AND THUNDERSTORMS THROUGH
MUCH OF THE PERIOD. AREAS OF FOG DEVELOPING AFTER 24/06Z WITH MVFR
CONDITIONS POSSIBLE AT KMEM AND KJBR...IFR CONDITIONS POSSIBLE AT
KMKL. WINDS BECOMING WESTERLY TODAY 8-9 KTS. WINDS LIGHT TONIGHT.
JCL
&&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-MISSISSIPPI-POINSETT-
RANDOLPH-ST. FRANCIS.
MO...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR DUNKLIN-
PEMISCOT.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1202 PM CDT Thu Jul 23 2015
.AVIATION...
/18Z TAFS/
All terminals should have VFR conditions through the next 24
hours. Stratus that degraded the southern terminals to MVFR this
morning should remain south of the southern terminals tomorrow
morning. Winds will remain southerly at 5 to 15 knots at all
terminals.
&&
.PREV DISCUSSION... /ISSUED 612 AM CDT Thu Jul 23 2015/
AVIATION...
/12Z TAFS/
Patchy MVFR stratus will persist across the northwest Hill Country
this morning, potentially affecting the KJCT terminal. This
stratus will erode by mid-morning with a high based cu field
anticipated this afternoon. A few showers will occur to the west
and northwest of KSWW, but will amount to little. Otherwise, dry
weather is expected across the area through the next 24 hours with
south winds around 10 kts.
25
PREV DISCUSSION... /ISSUED 324 AM CDT Thu Jul 23 2015/
SHORT TERM...
(Today and tonight)
The development of mid-level cumuliform clouds from Midland, to
Haskell, to Albany over the past few hours implies a region of
ascent moving across West TX. The TTU WRF and HRRR are hinting at
the potential for a few showers early this morning, but anything
that develops should remain west of Sweetwater. Farther south,
low stratus over the Hill County is increasing in coverage and
advecting north. This cloud cover will likely affect the
southeast portion of the CWA through around 9 AM. Otherwise,
expect hot and dry conditions across West Central TX with
afternoon highs in the upper 90s to around 101 degrees.
Skies will be mostly clear tonight, although a few low clouds
will be possible along the I-10 corridor after 3 AM. Winds will
remain under 10 mph with overnight lows in the mid 70s.
Johnson
LONG TERM...
(Friday through Wednesday)
No relief in sight from the heat in the extended forecast.
Temperatures may even get a degree or two hotter this weekend as
the center of upper level high pressure moves back over West
Texas, with highs in the 99 to 102 range.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 77 98 77 99 77 / 0 0 5 5 5
San Angelo 76 101 76 102 76 / 0 0 5 5 5
Junction 75 97 75 99 75 / 0 0 5 5 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/99
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
612 AM CDT Thu Jul 23 2015
.AVIATION...
/12Z TAFS/
Patchy MVFR stratus will persist across the northwest Hill Country
this morning, potentially affecting the KJCT terminal. This
stratus will erode by mid-morning with a high based cu field
anticipated this afternoon. A few showers will occur to the west
and northwest of KSWW, but will amount to little. Otherwise, dry
weather is expected across the area through the next 24 hours with
south winds around 10 kts.
25
&&
.PREV DISCUSSION... /ISSUED 324 AM CDT Thu Jul 23 2015/
SHORT TERM...
(Today and tonight)
The development of mid-level cumuliform clouds from Midland, to
Haskell, to Albany over the past few hours implies a region of
ascent moving across West TX. The TTU WRF and HRRR are hinting at
the potential for a few showers early this morning, but anything
that develops should remain west of Sweetwater. Farther south,
low stratus over the Hill County is increasing in coverage and
advecting north. This cloud cover will likely affect the
southeast portion of the CWA through around 9 AM. Otherwise,
expect hot and dry conditions across West Central TX with
afternoon highs in the upper 90s to around 101 degrees.
Skies will be mostly clear tonight, although a few low clouds
will be possible along the I-10 corridor after 3 AM. Winds will
remain under 10 mph with overnight lows in the mid 70s.
Johnson
LONG TERM...
(Friday through Wednesday)
No relief in sight from the heat in the extended forecast.
Temperatures may even get a degree or two hotter this weekend as
the center of upper level high pressure moves back over West
Texas, with highs in the 99 to 102 range.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 99 77 98 77 99 / 0 0 0 5 5
San Angelo 101 76 101 76 102 / 0 0 0 5 5
Junction 99 75 97 75 99 / 0 0 0 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
25
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
324 AM CDT Thu Jul 23 2015
.SHORT TERM...
(Today and tonight)
The development of mid-level cumuliform clouds from Midland, to
Haskell, to Albany over the past few hours implies a region of
ascent moving across West TX. The TTU WRF and HRRR are hinting at
the potential for a few showers early this morning, but anything
that develops should remain west of Sweetwater. Farther south,
low stratus over the Hill County is increasing in coverage and
advecting north. This cloud cover will likely affect the
southeast portion of the CWA through around 9 AM. Otherwise,
expect hot and dry conditions across West Central TX with
afternoon highs in the upper 90s to around 101 degrees.
Skies will be mostly clear tonight, although a few low clouds
will be possible along the I-10 corridor after 3 AM. Winds will
remain under 10 mph with overnight lows in the mid 70s.
Johnson
.LONG TERM...
(Friday through Wednesday)
No relief in sight from the heat in the extended forecast.
Temperatures may even get a degree or two hotter this weekend as
the center of upper level high pressure moves back over West
Texas, with highs in the 99 to 102 range.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 99 77 98 77 99 / 0 0 0 5 5
San Angelo 101 76 101 76 102 / 0 0 0 5 5
Junction 99 75 97 75 99 / 0 0 0 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/04
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
832 PM EDT FRI JUL 24 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION TONIGHT AND WILL REMAIN
OVER THE AREA THROUGH THE WEEKEND. A BACKDOOR COLD FRONT WILL MOVE
INTO THE AREA SUNDAY NIGHT AND MONDAY...THEN STALL...AND BE A
FOCUS FOR SHOWERS AND THUNDERSTORMS INTO AT LEAST TUESDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 822 PM EDT FRIDAY...
OTHER THAN FOR A FEW SPRINKLES ALONG THE FAR SOUTHERN BLUE
RIDGE...QUIET WEATHER PREVAILS THIS EVENING AND LOOKS TO CONTINUE
OVERNIGHT UNDER HIGH PRESSURE AND VERY DRY AIR ALOFT PER EVENING
SOUNDINGS. HOWEVER STILL SOME CONCERN ABOUT SOME LOW TOPPED
SHOWERS FORMING ACROSS THE SW UNDER THE MID LEVEL INVERSION
THROUGH LATE THIS EVENING AS MIXING WEAKENS AND MOISTURE POOLS A
BIT. ALSO SEEING A DECENT LOW LEVEL THETA-E RIDGE UP ALONG THE
BLUE RIDGE WHICH THE HRRR KEEPS FOCUS ALONG AS CU SPREADS OUT
UNDER THE DRY AIR ABOVE AFTER LOSS OF HEATING. SINCE THIS SOLUTION
HAS BEEN OVERDONE WILL ONLY KEEP AN ISOLATED MENTION GOING SOUTHERN
BLUE RIDGE A FEW MORE HOURS WITH PC TO CLEAR ELSW. OTHER CONCERN
WITH POSSIBLE FORMATION OF LOW CLOUDS EASTERN SLOPES LATE...AND
EXPANSE OF FOG BY FORMATION BY DAWN ESPCLY VALLEYS AND OUT EAST
WHERE DEWPOINTS ARE HIGHER. LATEST GUIDANCE STILL SUPPORTS QUITE A
BIT OF FOG SO INCLUDED SOME AREAS OF DENSE FOG VALLEYS AND LEFT
MUCH OF THE REST OF THE CWA IN PATCHY COVERAGE. OTRW BUMPED DOWN
LOW TEMPS A LITTLE IN THE WEST WHILE RAISING SOME SE BUT OVERALL
60S WITH A FEW 50S DEEPER VALLEYS.
PREVIOUS DISCUSSION AS OF 305 PM EDT FRIDAY...
UPPER LEVEL TROUGHINESS AND LOW LEVEL MOISTURE WILL KEEP MOSTLY
CLOUDY SKIES IN THE REGION THROUGH EARLY THIS EVENING. WITH LOSE OF
HEATING...CLOUDS WILL FADE THROUGH THE REST OF THE EVENING. AN
INVERSION WILL DEVELOP OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS IN
FROM THE OHIO VALLEY. MOISTURE TRAPPED UNDER THIS INVERSION MAY
BRING A LOW STRATUS DECK OVER THE AREA AND LINGER THROUGH SATURDAY
MORNING. AREAS NOT BEING OVERCOME BY THIS STRATUS DECK WILL LIKELY
HAVE PATCHY MORNING FOG...ESPECIALLY IN MOUNTAIN VALLEYS AND LOW
LYING AREAS. THIS FOG WILL BURN OFF QUICKER THAN THE STRATUS DECK
WILL. LIKE THIS AFTERNOON...UPPER LEVEL TROUGHINESS AND LOW LEVEL
MOISTURE WILL KEEP MOSTLY CLOUDY SKIES WITH TEMPERATURES NEAR
NORMAL. THE CHANCE FOR RAIN IS SMALL BUT POSSIBLE TOWARDS THE
EASTERN SLOPES OF THE NORTHWEST NORTH CAROLINA BLUE RIDGE. IT
APPEARS SOUTHEASTERLY UPSLOPE WINDS MAY HAVE ENOUGH MOISTURE TO
PRODUCE A FEW ISOLATED SHOWERS LATE IN THE AFTERNOON.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 318 PM EDT FRIDAY...
YOU CAN EXPECT TYPICAL SUMMER WX INTO SUNDAY...WITH WEAK BACKDOOR
FRONT TRYING TO MAKE IT INTO THE AREA MONDAY...BEFORE LIFTING NE
MONDAY NIGHT. THIS BOUNDARY PLUS SOME ENERGY ALOFT MAY ALLOW FOR
SCATTERED STRONGER STORMS TO FORM MONDAY...BUT STILL MOST AREAS WILL
BE DRY. KEPT POPS IN THE LOW CHANCE RANGE...WITH LESS COVERAGE
SUNDAY.
HIGHS SUNDAY-MONDAY WILL BE CLOSE TO NORMAL FROM THE LOWER TO MID
80S WEST TO UPPER 80S-LOWER 90S EAST.
LOW TEMPS WILL BE CREEPING BACK UP WITH HUMIDITY EXPECTED TO
INCREASE. LOWS SAT NIGHT WILL BE IN THE LOWER TO MID 60S MOUNTAINS
TO UPPER 60S EAST WARMING TO THE MID 60S MTNS SUNDAY AND MONDAY
NIGHT TO AROUND 70 EAST.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 138 PM EDT FRIDAY...
A BROAD UPPER RIDGE WILL STAY SITUATED FROM THE SOUTHERN PLAINS
EASTWARD TO THE CENTRAL AND SOUTHERN APPALACHIANS THROUGH LATE
WEDNESDAY NIGHT. THIS WILL KEEP US A BIT ON THE HUMID SIDE WITH
CLOSE TO SEASONAL TEMPS...HIGHS 80S MOUNTAINS TO LOW 90S EAST...WITH
ONLY A SCATTERING OF THUNDERSTORMS MAINLY DURING THE AFTERNOON/EARLY
EVENING PERIODS.
AS WE HEAD INTO THURSDAY AND FRIDAY...CLOSED LOW OVER THE CANADIAN
PRAIRIES EARLY IN THE PERIOD OPENS UP AS IT MOVES EAST INTO ONTARIO
AND QUEBEC. MODELS ARE FAVORING HEIGHTS LOWERING OVER THE MID
ATLANTIC DURING THIS TIME FRAME WITH A FRONTAL BOUNDARY MAKING
INROADS INTO THE MOUNTAINS BY FRIDAY AFTERNOON. THIS WILL START TO
INCREASE THE THREAT OF STORMS. AT THE MOMENT WILL ONLY ADVERTISE THE
USUAL CHANCE RANGE OF 30-50 PERCENT...BUT THINK NEXT FRIDAY WOULD
START TO FAVOR HIGHER POPS. TEMPS SHOULD FALL OFF SLIGHTLY...BUT
STILL THINK WITH FRONTAL BOUNDARY TO THE NORTHWEST...WE SHOULD STILL
SEE 80S MOUNTAINS TO NEAR 90 SOUTHEAST.
LOWS DURING THE PERIOD WILL BE IN THE LOWER TO MID 60S MOUNTAINS TO
UPPER 60S AROUND 70 EAST.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 800 PM EDT FRIDAY...
SATELLITE IMAGERY INDICATES DIMINISHING CU FOR MUCH OF THE
PIEDMONT REGION...WITH SCT TO BKN CU HOLDING ACROSS THE MOUNTAINS.
CEILINGS THERE ARE ONLY OCCASIONAL...WITH BASES RANGING FROM 4KFT
TO 7KFT MOST PLACES. THERE IS ENOUGH INSTABILITY PRESENT TO
SUPPORT TOWERING CU...PARTICULARLY ACROSS THE HIGHLANDS OF NORTH
CAROLINA UP THE CHAIN INTO VIRGINIA...AND RADAR INDICATES WEAK
SHOWERS ATTEMPTING TO BUBBLE UP FROM TIME TO TIME...ALTHOUGH A MID
LEVEL INVERSION IS KEEPING CONVECTION IN CHECK.
EXPECT TO SEE A FEW SHOWERS CONTINUE TO DEVELOP INTO LATE EVENING
GIVING LINGERING INSTABILITY...ESPECIALLY AS THE INVERSION
WEAKENS. DO NOT ANTICIPATE THUNDER HOWEVER. AFTER 25/06Z...EAST
SOUTHEASTERLY WINDFLOW WILL ALLOW FOR PATCHY STRATUS TO DEVELOP
ALONG AND EAST OF THE BLUE RIDGE. WILL ALSO SEE REDEVELOPMENT OF
RIVER VALLEY FOG FOR KLWB.
HIGH PRESSURE WILL REMAIN IN CONTROL ON SATURDAY...WITH DAYTIME
HEATING ERODING ANY SUB VFR CONDITIONS QUICKLY AFTER 25/13Z. EARLY
AFTERNOON WILL BRING REDEVELOPMENT OF CU FIELD ACROSS THE AREA...
WITH PERHAPS A FEW SHOWERS/ISOLATED BRIEF THUNDERSTORMS DEVELOPING
ALONG THE RIDGES WITH HEATING.
EXTENDED AVIATION FORECAST...
HIGH PRESSURE SHOULD STAY IN CONTROL OVERHEAD...AND MAINTAIN MAINLY
VFR CONDITIONS THROUGH THE REMAINDER OF THIS WEEKEND OUTSIDE OF
EARLY MORNING VALLEY FOG. SHOWER OR THUNDERSTORM ACTIVITY MAY
BECOME MORE ENHANCED BY MONDAY AND TUESDAY...WITH A BACKDOOR COLD
FRONT APPROACHING FROM THE COAST. A RETURN OF HAZY...HOT...AND
HUMID CONDITIONS APPEARS LIKELY BY THE MIDDLE OF THE WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RCS
NEAR TERM...JH/RCS
SHORT TERM...WP
LONG TERM...WP
AVIATION...NF/PW
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
143 PM EDT THU JUL 23 2015
.SYNOPSIS...
A STALLED FRONT WILL REMAIN SOUTH OF THE REGION FRIDAY. WEAK WAVES
OF LOW PRESSURE WILL TRACK ALONG THE FRONT TODAY AND
TONIGHT...WITH LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST ON
FRIDAY. HIGH PRESSURE WILL STRENGTHEN FRIDAY THROUGH THE
WEEKEND OVER THE MID ATLANTIC REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1255 PM EDT THURSDAY...
THE FIRST WAVE OF SHOWERS HAS EXITED THE SOUTHEAST PORTION OF THE
FORECAST AREA. THE LEADING EDGE OF THE NEXT REGION OF SHOWER
ACTIVITY WILL ENTER THE SOUTHWEST PART OF THE REGION AROUND 400
PM. HOWEVER...ISOLATED CONVECTION IS POSSIBLE AHEAD OF THIS MAIN
AREA ACROSS THE SOUTHERN THIRD OF THE REGION. THE BEST CHANCE OF
ANY THUNDERSTORMS WILL BE LATER THIS AFTERNOON IN AREAS NEAR AND
SOUTH OF THE NC/VA STATE LINE. HAVE MADE SOME MINOR ADJUSTMENTS
DOWNWARD OF THE FORECAST HIGH TEMPERATURES TODAY...MAINLY IN AREAS
ALONG AND NEAR THE NC/VA BORDER EAST OF I-77. RAIN FROM EARLIER
TODAY AND RESIDUAL CLOUD COVER IS PREVENTING AS QUICK OF A CLIMB
OF TEMPERATURES THAN EARLIER FORECAST.
AS OF 955 AM EDT THURSDAY...
MORNING UPDATE WILL REFLECT A MORE DISTINCT SEPARATION IN
PRECIPITATION COVERAGE ACROSS THE REGION. CURRENTLY RAIN SHOWERS
ARE EXITING THE SOUTHEAST PART OF THE REGION TO THE EAST...WITH NO
OTHER PRECIPITATION IN THE AREA. THEREFORE..HAVE REMOVED THE
PRECIPITATION CHANCES IN THE SOUTHWEST PARTS OF THE AREA UNTIL IT
HAS A CHANCE TO MOVE INTO REGION THIS AFTERNOON FROM THE WEST.
HAVE ALSO ADJUSTED HOURLY TEMPERATURE...DEW POINT AND SKY COVER
GRIDS THROUGH THE NEXT FEW HOURS BASED UPON THE CURRENT
OBSERVATIONS AND EXPECTED TRENDS INTO THE EARLY AFTERNOON.
AS OF 650 AM EDT THURSDAY...
SHORT WAVE WAS OVER THE MID MISSISSIPPI VALLEY EARLY THIS MORNING ND
WILL TRACK INTO THE CAROLINA BY FRIDAY MORNING. THE ASSOCIATED
PRECIPITATION WAS OVER TENNESSEE AND KENTUCKY AT 08Z. MODELS
BRING THE PRECIPITATION EAST ALONG THE 850 MB FRONT. LITTLE
MOVEMENT OF THE SURFACE FRONT IS EXPECTED TODAY AND INTO THIS
EVENING. SURFACE WINDS WILL BE LIGHT AND VARIABLE UNTIL THE SHORT
WAVE MOVES TO THE EAST...THEN PREVAILING FLOW WILL BE OUT OF THE
NORTHEAST. UNTIL THEN COUNTY WARNING AREA IS IN BETWEEN THE FRONT
OVER THE CAROLINAS AND HIGH PRESSURE OVER THE OHIO VALLEY.
HAVE RAISED PROBABILITY OF PRECIPITATION TO ACCOUNT BASED ON RADAR
TRENDS. HRRR AND LOCAL WRF BRING NEXT BATCH OF PRECIPITATION IN
AFTER 15Z/10AM. MODELS SIMILAR WITH NORTHERN EXTENT OF THE BEST
PROBABILITY OF PRECIPITATION. HIGHER CONVECTIVE AVAILABLE
POTENTIAL ENERGY AND LOWER LIFTED INDEX VALUES WILL BE ALONG AND
SOUTH OF ROUTE 460. WILL KEEP HIGHEST PROBABILITY OF PRECIPITATION
IN THE SOUTHERN HALF OF THE FORECAST AREA THIS AFTERNOON AND
EVENING. THIS ALSO LINES UP WITH PRECIPITABLE WATER VALUES OF 1.5
TO 2.0 INCHES. THIS DEEPER MOISTURE BEGINS TO EXIT SOUTHEAST OUT
OF THE FORECAST AREA LATE TONIGHT. HOWEVER...NORTHEAST WINDS AND
LOW LEVEL MOISTURE WILL KEEP LOW CLOUDS AND FOG IN THE
REGION...ESPECIALLY IN THE EASTERN UPSLOPE AREA OF THE
APPALACHIANS.
DRIER AIR COMING IN THE NORTH ERN COUNTY WARNING AREA AND LESS CLOUD
COVER COMPARED TO MORE CLOUDS IN THE CENTRAL AND SOUTHERN COUNTY
WARNING AREA WILL RESULT IN A LARGE SPREAD OF MINIMUM
TEMPERATURES. DO NOT EXPECT AS MUCH OF A DROP I N HE SOUTH...WHILE
NORTHERN COUNTIES MAY LOWER INTO THE 50S. LOCAL WRF GUIDANCE
LOOKED REASONABLE FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
LOW PRESSURE JUST OFF THE NORTH CAROLINA COAST FRIDAY MORNING WILL
MOVE EAST INTO THE ATLANTIC OCEAN THROUGH THE PERIOD. MEANWHILE HIGH
PRESSURE TO OUR NORTHWEST WILL BUILD SOUTH ON FRIDAY AND MOVE ACROSS
THE MID ATLANTIC REGION INTO SATURDAY NIGHT. THE COMBINATION OF
HEATING...DESTABILIZATION...MOISTURE SFC FLOW OVER HIGHER TERRAIN
SUPPORTS THE MENTION OF ISOLATED TO WIDELY SCATTERED CONVECTION
CROSS THE SOUTHWEST. HIGH TEMPERATURES FRIDAY WILL CLIMB TO NEAR
80 DEGREES IN THE WEST TO THE UPPER 80S IN THE EAST. TAPER OFF
ISOLATED SHOWERS FRIDAY NIGHT BY MIDNIGHT AND ADDED SOME PATCHY
FOG FRIDAY NIGHT INTO SATURDAY MORNING. LOW TEMPERATURES FRIDAY
NIGHT WILL VARY FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S
IN THE PIEDMONT.
EXPECT A NICE SATURDAY WITH ONLY AN ISOLATED CHANCE OF SHOWERS
ACROSS THE MOUNTAINS. HIGH TEMPERATURES SATURDAY WILL MODERATE INTO
THE LOWER 80S IN THE MOUNTAINS TO AROUND 90 DEGREES IN THE PIEDMONT.
YOU CAN ANTICIPATE DRY WEATHER FOR SATURDAY NIGHT WITH LOW
TEMPERATURES FROM THE LOWER 60S IN THE WEST TO THE MID 60S IN THE
EAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 240 PM EDT WEDNESDAY...
GOING TO UPPER RIDGE START TO LEAN WEST TO EAST ACROSS THE SOUTHERN
PLAINS TO THE APPALACHIANS THIS PERIOD WITH GRADUALLY BUILDING
HEIGHTS. OUR REGION WILL STAY IN A NW FLOW ALOFT THIS SUNDAY THEN
MORE NORTHERLY BY TUESDAY-WEDNESDAY. MEAN SOLUTION OF MODELS SUGGEST
NOT BIG THREAT OF CONVECTION THIS PERIOD...THOUGH BEST SHOT WILL BE
PERHAPS MONDAY AS SHORTWAVE MOVES FROM OHIO TO THE MID ATLANTIC
SETTING UP SOME HEIGHT FALLS OVER VIRGINIA...AND WEAK FRONTAL
BOUNDARY PASSING ACROSS. AT THIS TIME WILL MAINTAIN IN THE CHANCE
RANGE FOR POPS.
WILL START TO SEE HUMIDITY ELEVATE ONCE AGAIN WITH BUILDING HEIGHTS
AND LIGHT SOUTHEAST TO SOUTHWEST WINDS IN THE SFC TO LOW LVLS.
HIGHS AND LOWS WILL BE CLOSE TO NORMAL FOR LATE JULY WITH MID 60S
MOUNTAINS TO AROUND 70 PIEDMONT FOR LOWS...AND HIGHS IN THE LOWER TO
MID 80S MOUNTAINS TO AROUND 90 PIEDMONT...INCLUDING ROANOKE CITY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 135 PM EDT THURSDAY...
POCKETS OF MVFR CIGS EXIST OVER PORTIONS OF NORTHWEST NORTH
CAROLINA AND NEIGHBORING SECTIONS OF SOUTHWEST VIRGINIA...AS WELL
AS...SOME ISOLATED SHOWERS. ELSEWHERE ACROSS THE REGION...VFR
SKIES PREVAILED WITH NO PRECIPITATION. THIS SCENARIO WILL BE
CHANGING.
AN UPPER LEVEL DISTURBANCE IS CURRENTLY PROGRESSING EASTWARD
THROUGH KY/TN ALONG A STALLED FRONTAL BOUNDARY. TRAJECTORIES OF
THIS SYSTEM TAKE THE BULK OF THE ASSOCIATED PRECIPITATION ACROSS
THE SOUTHWEST PORTION OF THE FORECAST AREA THIS AFTERNOON INTO
THE EVENING HOURS. ISOLATED COVERAGE REACHES NORTH CLOSE TO A
KBLF-KBCB-KROA LINE BY LATE THIS AFTERNOON. ISOLATED TO SCATTERED
THUNDERSTORMS WILL ALSO BE POSSIBLE...ESPECIALLY ACROSS THE
SOUTHWEST AND SOUTHERN PARTS OF THE REGION.
THIS SYSTEM WILL BE ALONG THE COAST LATE THIS EVENING...AND ALLOW
FOR OUR LOW LEVEL WINDS TO TAKE ON MORE OF A NORTHEAST TO EAST
TRAJECTORY. THE REGION WILL END UP WITH A NOSE OF MOISTURE WITH
ATLANTIC ORIGINS OVERSPREAD BY MUCH DRIER AIR ALOFT. THIS LOW
LEVEL MOISTURE INVERSION WILL YIELD IFR/MVFR CIGS/VSBYS OVER MUCH
OF THE REGION DURING THE OVERNIGHT HOURS...ESPECIALLY IN AREAS
ALONG AND EAST OF THE CREST OF THE BLUE RIDGE.
THE INVERSION IS EXPECTED TO BREAK BY THE MID TO LATE MORNING ON
FRIDAY AND YIELD VFR CONDITIONS TO THE ENTIRE REGION.
EXTENDED AVIATION FORECAST...
FRIDAY THROUGH EARLY NEXT WEEK...HIGH PRESSURE WILL BE THE
DOMINATE WEATHER FEATURE ACROSS THE REGION. MAINLY VFR CONDITIONS
ARE EXPECTED EXCEPT FOR THE POTENTIAL OF LATE NIGHT AND EARLY
MORNING MOUNTAIN VALLEY FOG. ISOLATED SHOWERS AND STORMS CANNOT BE
RULED OUT...BUT WILL CERTAINLY BE THE EXCEPTION TO THE RULE
A WEAK BACKDOOR FRONT MAY ENTER THE REGION LATE SUNDAY NIGHT INTO
MONDAY. THIS WOULD EXPAND SHOWER AND THUNDERSTORMS COVERAGE MONDAY
INTO TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/DS
SHORT TERM...KK
LONG TERM...WP
AVIATION...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
101 PM EDT THU JUL 23 2015
.SYNOPSIS...
A STALLED FRONT WILL REMAIN SOUTH OF THE REGION FRIDAY. WEAK WAVES
OF LOW PRESSURE WILL TRACK ALONG THE FRONT TODAY AND
TONIGHT...WITH LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST ON
FRIDAY. HIGH PRESSURE WILL STRENGTHEN FRIDAY THROUGH THE
WEEKEND OVER THE MID ATLANTIC REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1255 PM EDT THURSDAY...
THE FIRST WAVE OF SHOWERS HAS EXITED THE SOUTHEAST PORTION OF THE
FORECAST AREA. THE LEADING EDGE OF THE NEXT REGION OF SHOWER
ACTIVITY WILL ENTER THE SOUTHWEST PART OF THE REGION AROUND 400
PM. HOWEVER...ISOLATED CONVECTION IS POSSIBLE AHEAD OF THIS MAIN
AREA ACROSS THE SOUTHERN THIRD OF THE REGION. THE BEST CHANCE OF
ANY THUNDERSTORMS WILL BE LATER THIS AFTERNOON IN AREAS NEAR AND
SOUTH OF THE NC/VA STATE LINE. HAVE MADE SOME MINOR ADJUSTMENTS
DOWNWARD OF THE FORECAST HIGH TEMPERATURES TODAY...MAINLY IN AREAS
ALONG AND NEAR THE NC/VA BORDER EAST OF I-77. RAIN FROM EARLIER
TODAY AND RESIDUAL CLOUD COVER IS PREVENTING AS QUICK OF A CLIMB
OF TEMPERATURES THAN EARLIER FORECAST.
AS OF 955 AM EDT THURSDAY...
MORNING UPDATE WILL REFLECT A MORE DISTINCT SEPARATION IN
PRECIPITATION COVERAGE ACROSS THE REGION. CURRENTLY RAIN SHOWERS
ARE EXITING THE SOUTHEAST PART OF THE REGION TO THE EAST...WITH NO
OTHER PRECIPITATION IN THE AREA. THEREFORE..HAVE REMOVED THE
PRECIPITATION CHANCES IN THE SOUTHWEST PARTS OF THE AREA UNTIL IT
HAS A CHANCE TO MOVE INTO REGION THIS AFTERNOON FROM THE WEST.
HAVE ALSO ADJUSTED HOURLY TEMPERATURE...DEW POINT AND SKY COVER
GRIDS THROUGH THE NEXT FEW HOURS BASED UPON THE CURRENT
OBSERVATIONS AND EXPECTED TRENDS INTO THE EARLY AFTERNOON.
AS OF 650 AM EDT THURSDAY...
SHORT WAVE WAS OVER THE MID MISSISSIPPI VALLEY EARLY THIS MORNING ND
WILL TRACK INTO THE CAROLINA BY FRIDAY MORNING. THE ASSOCIATED
PRECIPITATION WAS OVER TENNESSEE AND KENTUCKY AT 08Z. MODELS
BRING THE PRECIPITATION EAST ALONG THE 850 MB FRONT. LITTLE
MOVEMENT OF THE SURFACE FRONT IS EXPECTED TODAY AND INTO THIS
EVENING. SURFACE WINDS WILL BE LIGHT AND VARIABLE UNTIL THE SHORT
WAVE MOVES TO THE EAST...THEN PREVAILING FLOW WILL BE OUT OF THE
NORTHEAST. UNTIL THEN COUNTY WARNING AREA IS IN BETWEEN THE FRONT
OVER THE CAROLINAS AND HIGH PRESSURE OVER THE OHIO VALLEY.
HAVE RAISED PROBABILITY OF PRECIPITATION TO ACCOUNT BASED ON RADAR
TRENDS. HRRR AND LOCAL WRF BRING NEXT BATCH OF PRECIPITATION IN
AFTER 15Z/10AM. MODELS SIMILAR WITH NORTHERN EXTENT OF THE BEST
PROBABILITY OF PRECIPITATION. HIGHER CONVECTIVE AVAILABLE
POTENTIAL ENERGY AND LOWER LIFTED INDEX VALUES WILL BE ALONG AND
SOUTH OF ROUTE 460. WILL KEEP HIGHEST PROBABILITY OF PRECIPITATION
IN THE SOUTHERN HALF OF THE FORECAST AREA THIS AFTERNOON AND
EVENING. THIS ALSO LINES UP WITH PRECIPITABLE WATER VALUES OF 1.5
TO 2.0 INCHES. THIS DEEPER MOISTURE BEGINS TO EXIT SOUTHEAST OUT
OF THE FORECAST AREA LATE TONIGHT. HOWEVER...NORTHEAST WINDS AND
LOW LEVEL MOISTURE WILL KEEP LOW CLOUDS AND FOG IN THE
REGION...ESPECIALLY IN THE EASTERN UPSLOPE AREA OF THE
APPALACHIANS.
DRIER AIR COMING IN THE NORTH ERN COUNTY WARNING AREA AND LESS CLOUD
COVER COMPARED TO MORE CLOUDS IN THE CENTRAL AND SOUTHERN COUNTY
WARNING AREA WILL RESULT IN A LARGE SPREAD OF MINIMUM
TEMPERATURES. DO NOT EXPECT AS MUCH OF A DROP I N HE SOUTH...WHILE
NORTHERN COUNTIES MAY LOWER INTO THE 50S. LOCAL WRF GUIDANCE
LOOKED REASONABLE FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
LOW PRESSURE JUST OFF THE NORTH CAROLINA COAST FRIDAY MORNING WILL
MOVE EAST INTO THE ATLANTIC OCEAN THROUGH THE PERIOD. MEANWHILE HIGH
PRESSURE TO OUR NORTHWEST WILL BUILD SOUTH ON FRIDAY AND MOVE ACROSS
THE MID ATLANTIC REGION INTO SATURDAY NIGHT. THE COMBINATION OF
HEATING...DESTABILIZATION...MOISTURE SFC FLOW OVER HIGHER TERRAIN
SUPPORTS THE MENTION OF ISOLATED TO WIDELY SCATTERED CONVECTION
CROSS THE SOUTHWEST. HIGH TEMPERATURES FRIDAY WILL CLIMB TO NEAR
80 DEGREES IN THE WEST TO THE UPPER 80S IN THE EAST. TAPER OFF
ISOLATED SHOWERS FRIDAY NIGHT BY MIDNIGHT AND ADDED SOME PATCHY
FOG FRIDAY NIGHT INTO SATURDAY MORNING. LOW TEMPERATURES FRIDAY
NIGHT WILL VARY FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S
IN THE PIEDMONT.
EXPECT A NICE SATURDAY WITH ONLY AN ISOLATED CHANCE OF SHOWERS
ACROSS THE MOUNTAINS. HIGH TEMPERATURES SATURDAY WILL MODERATE INTO
THE LOWER 80S IN THE MOUNTAINS TO AROUND 90 DEGREES IN THE PIEDMONT.
YOU CAN ANTICIPATE DRY WEATHER FOR SATURDAY NIGHT WITH LOW
TEMPERATURES FROM THE LOWER 60S IN THE WEST TO THE MID 60S IN THE
EAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 240 PM EDT WEDNESDAY...
GOING TO UPPER RIDGE START TO LEAN WEST TO EAST ACROSS THE SOUTHERN
PLAINS TO THE APPALACHIANS THIS PERIOD WITH GRADUALLY BUILDING
HEIGHTS. OUR REGION WILL STAY IN A NW FLOW ALOFT THIS SUNDAY THEN
MORE NORTHERLY BY TUESDAY-WEDNESDAY. MEAN SOLUTION OF MODELS SUGGEST
NOT BIG THREAT OF CONVECTION THIS PERIOD...THOUGH BEST SHOT WILL BE
PERHAPS MONDAY AS SHORTWAVE MOVES FROM OHIO TO THE MID ATLANTIC
SETTING UP SOME HEIGHT FALLS OVER VIRGINIA...AND WEAK FRONTAL
BOUNDARY PASSING ACROSS. AT THIS TIME WILL MAINTAIN IN THE CHANCE
RANGE FOR POPS.
WILL START TO SEE HUMIDITY ELEVATE ONCE AGAIN WITH BUILDING HEIGHTS
AND LIGHT SOUTHEAST TO SOUTHWEST WINDS IN THE SFC TO LOW LVLS.
HIGHS AND LOWS WILL BE CLOSE TO NORMAL FOR LATE JULY WITH MID 60S
MOUNTAINS TO AROUND 70 PIEDMONT FOR LOWS...AND HIGHS IN THE LOWER TO
MID 80S MOUNTAINS TO AROUND 90 PIEDMONT...INCLUDING ROANOKE CITY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 735 AM EDT THURSDAY...
BASED ON THE LATEST RADAR TRENDS AND WATER VAPOR SATELLITE LOOP...SCATTERED
SHOWERS WILL MOVE ACROSS NORTHERN NORTH CAROLINA AND EXTREME
SOUTHERN VIRGINIA THIS MORNING. HOWEVER...VISIBILITIES WILL REMAIN
VFR....EVEN WITH THE RAIN...AT KLYH AND KDAN.
A SHORT WAVE OVER MISSOURI EARLY THIS MORNING WILL TRACK INTO THE
CAROLINAS BY FRIDAY MORNING. THE ASSOCIATED SHOWERS AND
THUNDERSTORMS OVER KENTUCKY AND TENNESSEE WILL MOVE EAST BRINGING
MORE PRECIPITATION TO SOUTHERN VIRGINIA AND NORTHERN NORTH
CAROLINA BY EARLY THIS AFTERNOON. MODELS IN DECENT AGREEMENT THAT
NORTHERN EDGE OF THE PRECIPITATION CHANCE WILL STAY JUST SOUTH OF
KBLF/KROA/KLYH. KDAN HAS THE BEST CHANCE OF SHOWERS TODAY...WHICH
MAY RESULT IN BRIEF MVFR CONDITIONS. OTHERWISE CEILINGS AND
VISIBILITIES WILL BE VFR. THE FRONT AND DEEP MOISTURE PUSH SOUTH
OUT OF THE AREA TONIGHT.
SURFACE AND LOW LEVEL WINDS BECOME EAST TO NORTHEAST TONIGHT. THIS
WILL BRING MOISTURE UP AGAINST THE EAST SLOPES OF THE
APPALACHIANS. HAVE ADDED MVFR FOG AND CLOUDS IN FOR KROA/KDAN AND
KLYH AFTER MIDNIGHT. MEDIUM CONFIDENCE ON THESE CEILING
HEIGHTS...MAY END UP BEING MUCH LOWER.
EXTENDED AVIATION FORECAST...
FRIDAY THROUGH EARLY NEXT WEEK...HIGH PRESSURE WILL BE THE
DOMINATE WEATHER FEATURE ACROSS THE REGION. MAINLY VFR CONDITIONS
ARE EXPECTED EXCEPT FOR THE POTENTIAL OF LATE NIGHT AND EARLY
MORNING MOUNTAIN VALLEY FOG. ISOLATED SHOWERS AND STORMS CANNOT BE
RULED OUT...ESPECIALLY OVER THE MOUNTAINS ON SUNDAY AFTERNOON.
A WEAK BACKDOOR FRONT MAY ENTER THE REGION LATE SUNDAY NIGHT INTO
MONDAY. THIS WOULD EXPAND SHOWER AND THUNDERSTORMS COVERAGE MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/DS
SHORT TERM...KK
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1002 AM EDT THU JUL 23 2015
.SYNOPSIS...
A STALLED FRONT WILL REMAIN SOUTH OF THE REGION FRIDAY. WEAK WAVES
OF LOW PRESSURE WILL TRACK ALONG THE FRONT TODAY AND
TONIGHT...WITH LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST ON
FRIDAY. HIGH PRESSURE WILL STRENGTHEN FRIDAY THROUGH THE
WEEKEND OVER THE MID ATLANTIC REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1055 AM EDT THURSDAY...
MORNING UPDATE WILL REFLECT A MORE DISTINCT SEPARATION IN
PRECIPITATION COVERAGE ACROSS THE REGION. CURRENTLY RAIN SHOWERS
ARE EXITING THE SOUTHEAST PART OF THE REGION TO THE EAST...WITH NO
OTHER PRECIPITATION IN THE AREA. THEREFORE..HAVE REMOVED THE
PRECIPITATION CHANCES IN THE SOUTHWEST PARTS OF THE AREA UNTIL IT
HAS A CHANCE TO MOVE INTO REGION THIS AFTERNOON FROM THE WEST.
HAVE ALSO ADJUSTED HOURLY TEMPERATURE...DEW POINT AND SKY COVER
GRIDS THROUGH THE NEXT FEW HOURS BASED UPON THE CURRENT
OBSERVATIONS AND EXPECTED TRENDS INTO THE EARLY AFTERNOON.
AS OF 650 AM EDT THURSDAY...
SHORT WAVE WAS OVER THE MID MISSISSIPPI VALLEY EARLY THIS MORNING ND
WILL TRACK INTO THE CAROLINA BY FRIDAY MORNING. THE ASSOCIATED
PRECIPITATION WAS OVER TENNESSEE AND KENTUCKY AT 08Z. MODELS
BRING THE PRECIPITATION EAST ALONG THE 850 MB FRONT. LITTLE
MOVEMENT OF THE SURFACE FRONT IS EXPECTED TODAY AND INTO THIS
EVENING. SURFACE WINDS WILL BE LIGHT AND VARIABLE UNTIL THE SHORT
WAVE MOVES TO THE EAST...THEN PREVAILING FLOW WILL BE OUT OF THE
NORTHEAST. UNTIL THEN COUNTY WARNING AREA IS IN BETWEEN THE FRONT
OVER THE CAROLINAS AND HIGH PRESSURE OVER THE OHIO VALLEY.
HAVE RAISED PROBABILITY OF PRECIPITATION TO ACCOUNT BASED ON RADAR
TRENDS. HRRR AND LOCAL WRF BRING NEXT BATCH OF PRECIPITATION IN
AFTER 15Z/10AM. MODELS SIMILAR WITH NORTHERN EXTENT OF THE BEST
PROBABILITY OF PRECIPITATION. HIGHER CONVECTIVE AVAILABLE
POTENTIAL ENERGY AND LOWER LIFTED INDEX VALUES WILL BE ALONG AND
SOUTH OF ROUTE 460. WILL KEEP HIGHEST PROBABILITY OF PRECIPITATION
IN THE SOUTHERN HALF OF THE FORECAST AREA THIS AFTERNOON AND
EVENING. THIS ALSO LINES UP WITH PRECIPITABLE WATER VALUES OF 1.5
TO 2.0 INCHES. THIS DEEPER MOISTURE BEGINS TO EXIT SOUTHEAST OUT
OF THE FORECAST AREA LATE TONIGHT. HOWEVER...NORTHEAST WINDS AND
LOW LEVEL MOISTURE WILL KEEP LOW CLOUDS AND FOG IN THE
REGION...ESPECIALLY IN THE EASTERN UPSLOPE AREA OF THE
APPALACHIANS.
DRIER AIR COMING IN THE NORTH ERN COUNTY WARNING AREA AND LESS CLOUD
COVER COMPARED TO MORE CLOUDS IN THE CENTRAL AND SOUTHERN COUNTY
WARNING AREA WILL RESULT IN A LARGE SPREAD OF MINIMUM
TEMPERATURES. DO NOT EXPECT AS MUCH OF A DROP I N HE SOUTH...WHILE
NORTHERN COUNTIES MAY LOWER INTO THE 50S. LOCAL WRF GUIDANCE
LOOKED REASONABLE FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
LOW PRESSURE JUST OFF THE NORTH CAROLINA COAST FRIDAY MORNING WILL
MOVE EAST INTO THE ATLANTIC OCEAN THROUGH THE PERIOD. MEANWHILE HIGH
PRESSURE TO OUR NORTHWEST WILL BUILD SOUTH ON FRIDAY AND MOVE ACROSS
THE MID ATLANTIC REGION INTO SATURDAY NIGHT. THE COMBINATION OF
HEATING...DESTABILIZATION...MOISTURE SFC FLOW OVER HIGHER TERRAIN
SUPPORTS THE MENTION OF ISOLATED TO WIDELY SCATTERED CONVECTION
CROSS THE SOUTHWEST. HIGH TEMPERATURES FRIDAY WILL CLIMB TO NEAR
80 DEGREES IN THE WEST TO THE UPPER 80S IN THE EAST. TAPER OFF
ISOLATED SHOWERS FRIDAY NIGHT BY MIDNIGHT AND ADDED SOME PATCHY
FOG FRIDAY NIGHT INTO SATURDAY MORNING. LOW TEMPERATURES FRIDAY
NIGHT WILL VARY FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S
IN THE PIEDMONT.
EXPECT A NICE SATURDAY WITH ONLY AN ISOLATED CHANCE OF SHOWERS
ACROSS THE MOUNTAINS. HIGH TEMPERATURES SATURDAY WILL MODERATE INTO
THE LOWER 80S IN THE MOUNTAINS TO AROUND 90 DEGREES IN THE PIEDMONT.
YOU CAN ANTICIPATE DRY WEATHER FOR SATURDAY NIGHT WITH LOW
TEMPERATURES FROM THE LOWER 60S IN THE WEST TO THE MID 60S IN THE
EAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 240 PM EDT WEDNESDAY...
GOING TO UPPER RIDGE START TO LEAN WEST TO EAST ACROSS THE SOUTHERN
PLAINS TO THE APPALACHIANS THIS PERIOD WITH GRADUALLY BUILDING
HEIGHTS. OUR REGION WILL STAY IN A NW FLOW ALOFT THIS SUNDAY THEN
MORE NORTHERLY BY TUESDAY-WEDNESDAY. MEAN SOLUTION OF MODELS SUGGEST
NOT BIG THREAT OF CONVECTION THIS PERIOD...THOUGH BEST SHOT WILL BE
PERHAPS MONDAY AS SHORTWAVE MOVES FROM OHIO TO THE MID ATLANTIC
SETTING UP SOME HEIGHT FALLS OVER VIRGINIA...AND WEAK FRONTAL
BOUNDARY PASSING ACROSS. AT THIS TIME WILL MAINTAIN IN THE CHANCE
RANGE FOR POPS.
WILL START TO SEE HUMIDITY ELEVATE ONCE AGAIN WITH BUILDING HEIGHTS
AND LIGHT SOUTHEAST TO SOUTHWEST WINDS IN THE SFC TO LOW LVLS.
HIGHS AND LOWS WILL BE CLOSE TO NORMAL FOR LATE JULY WITH MID 60S
MOUNTAINS TO AROUND 70 PIEDMONT FOR LOWS...AND HIGHS IN THE LOWER TO
MID 80S MOUNTAINS TO AROUND 90 PIEDMONT...INCLUDING ROANOKE CITY.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
AS OF 735 AM EDT THURSDAY...
BASED ON THE LATEST RADAR TRENDS AND WATER VAPOR SATELLITE LOOP...SCATTERED
SHOWERS WILL MOVE ACROSS NORTHERN NORTH CAROLINA AND EXTREME
SOUTHERN VIRGINIA THIS MORNING. HOWEVER...VISIBILITIES WILL REMAIN
VFR....EVEN WITH THE RAIN...AT KLYH AND KDAN.
A SHORT WAVE OVER MISSOURI EARLY THIS MORNING WILL TRACK INTO THE
CAROLINAS BY FRIDAY MORNING. THE ASSOCIATED SHOWERS AND
THUNDERSTORMS OVER KENTUCKY AND TENNESSEE WILL MOVE EAST BRINGING
MORE PRECIPITATION TO SOUTHERN VIRGINIA AND NORTHERN NORTH
CAROLINA BY EARLY THIS AFTERNOON. MODELS IN DECENT AGREEMENT THAT
NORTHERN EDGE OF THE PRECIPITATION CHANCE WILL STAY JUST SOUTH OF
KBLF/KROA/KLYH. KDAN HAS THE BEST CHANCE OF SHOWERS TODAY...WHICH
MAY RESULT IN BRIEF MVFR CONDITIONS. OTHERWISE CEILINGS AND
VISIBILITIES WILL BE VFR. THE FRONT AND DEEP MOISTURE PUSH SOUTH
OUT OF THE AREA TONIGHT.
SURFACE AND LOW LEVEL WINDS BECOME EAST TO NORTHEAST TONIGHT. THIS
WILL BRING MOISTURE UP AGAINST THE EAST SLOPES OF THE
APPALACHIANS. HAVE ADDED MVFR FOG AND CLOUDS IN FOR KROA/KDAN AND
KLYH AFTER MIDNIGHT. MEDIUM CONFIDENCE ON THESE CEILING
HEIGHTS...MAY END UP BEING MUCH LOWER.
EXTENDED AVIATION FORECAST...
FRIDAY THROUGH EARLY NEXT WEEK...HIGH PRESSURE WILL BE THE
DOMINATE WEATHER FEATURE ACROSS THE REGION. MAINLY VFR CONDITIONS
ARE EXPECTED EXCEPT FOR THE POTENTIAL OF LATE NIGHT AND EARLY
MORNING MOUNTAIN VALLEY FOG. ISOLATED SHOWERS AND STORMS CANNOT BE
RULED OUT...ESPECIALLY OVER THE MOUNTAINS ON SUNDAY AFTERNOON.
A WEAK BACKDOOR FRONT MAY ENTER THE REGION LATE SUNDAY NIGHT INTO
MONDAY. THIS WOULD EXPAND SHOWER AND THUNDERSTORMS COVERAGE MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/DS
SHORT TERM...KK
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
737 AM EDT THU JUL 23 2015
.SYNOPSIS...
A STALLED FRONT WILL REMAIN SOUTH OF THE REGION FRIDAY. WEAK WAVES
OF LOW PRESSURE WILL TRACK ALONG THE FRONT TODAY AND
TONIGHT...WITH LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST ON
FRIDAY. HIGH PRESSURE WILL STRENGTHEN FRIDAY THROUGH THE
WEEKEND OVER THE MID ATLANTIC REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM EDT THURSDAY...
SHORT WAVE WAS OVER THE MID MISSISSIPPI VALLEY EARLY THIS MORNING ND
WILL TRACK INTO THE CAROLINA BY FRIDAY MORNING. THE ASSOCIATED
PRECIPITATION WAS OVER TENNESSEE AND KENTUCKY AT 08Z. MODELS
BRING THE PRECIPITATION EAST ALONG THE 850 MB FRONT. LITTLE
MOVEMENT OF THE SURFACE FRONT IS EXPECTED TODAY AND INTO THIS
EVENING. SURFACE WINDS WILL BE LIGHT AND VARIABLE UNTIL THE SHORT
WAVE MOVES TO THE EAST...THEN PREVAILING FLOW WILL BE OUT OF THE
NORTHEAST. UNTIL THEN COUNTY WARNING AREA IS IN BETWEEN THE FRONT
OVER THE CAROLINAS AND HIGH PRESSURE OVER THE OHIO VALLEY.
HAVE RAISED PROBABILITY OF PRECIPITATION TO ACCOUNT BASED ON RADAR
TRENDS. HRRR AND LOCAL WRF BRING NEXT BATCH OF PRECIPITATION IN
AFTER 15Z/10AM. MODELS SIMILAR WITH NORTHERN EXTENT OF THE BEST
PROBABILITY OF PRECIPITATION. HIGHER CONVECTIVE AVAILABLE
POTENTIAL ENERGY AND LOWER LIFTED INDEX VALUES WILL BE ALONG AND
SOUTH OF ROUTE 460. WILL KEEP HIGHEST PROBABILITY OF PRECIPITATION
IN THE SOUTHERN HALF OF THE FORECAST AREA THIS AFTERNOON AND
EVENING. THIS ALSO LINES UP WITH PRECIPITABLE WATER VALUES OF 1.5
TO 2.0 INCHES. THIS DEEPER MOISTURE BEGINS TO EXIT SOUTHEAST OUT
OF THE FORECAST AREA LATE TONIGHT. HOWEVER...NORTHEAST WINDS AND
LOW LEVEL MOISTURE WILL KEEP LOW CLOUDS AND FOG IN THE
REGION...ESPECIALLY IN THE EASTERN UPSLOPE AREA OF THE
APPALACHIANS.
DRIER AIR COMING IN THE NORTH ERN COUNTY WARNING AREA AND LESS CLOUD
COVER COMPARED TO MORE CLOUDS IN THE CENTRAL AND SOUTHERN COUNTY
WARNING AREA WILL RESULT IN A LARGE SPREAD OF MINIMUM
TEMPERATURES. DO NOT EXPECT AS MUCH OF A DROP I N HE SOUTH...WHILE
NORTHERN COUNTIES MAY LOWER INTO THE 50S. LOCAL WRF GUIDANCE
LOOKED REASONABLE FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
LOW PRESSURE JUST OFF THE NORTH CAROLINA COAST FRIDAY MORNING WILL
MOVE EAST INTO THE ATLANTIC OCEAN THROUGH THE PERIOD. MEANWHILE HIGH
PRESSURE TO OUR NORTHWEST WILL BUILD SOUTH ON FRIDAY AND MOVE ACROSS
THE MID ATLANTIC REGION INTO SATURDAY NIGHT. THE COMBINATION OF
HEATING...DESTABILIZATION...MOISTURE SFC FLOW OVER HIGHER TERRAIN
SUPPORTS THE MENTION OF ISOLATED TO WIDELY SCATTERED CONVECTION
CROSS THE SOUTHWEST. HIGH TEMPERATURES FRIDAY WILL CLIMB TO NEAR
80 DEGREES IN THE WEST TO THE UPPER 80S IN THE EAST. TAPER OFF
ISOLATED SHOWERS FRIDAY NIGHT BY MIDNIGHT AND ADDED SOME PATCHY
FOG FRIDAY NIGHT INTO SATURDAY MORNING. LOW TEMPERATURES FRIDAY
NIGHT WILL VARY FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S
IN THE PIEDMONT.
EXPECT A NICE SATURDAY WITH ONLY AN ISOLATED CHANCE OF SHOWERS
ACROSS THE MOUNTAINS. HIGH TEMPERATURES SATURDAY WILL MODERATE INTO
THE LOWER 80S IN THE MOUNTAINS TO AROUND 90 DEGREES IN THE PIEDMONT.
YOU CAN ANTICIPATE DRY WEATHER FOR SATURDAY NIGHT WITH LOW
TEMPERATURES FROM THE LOWER 60S IN THE WEST TO THE MID 60S IN THE
EAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 240 PM EDT WEDNESDAY...
GOING TO UPPER RIDGE START TO LEAN WEST TO EAST ACROSS THE SOUTHERN
PLAINS TO THE APPALACHIANS THIS PERIOD WITH GRADUALLY BUILDING
HEIGHTS. OUR REGION WILL STAY IN A NW FLOW ALOFT THIS SUNDAY THEN
MORE NORTHERLY BY TUESDAY-WEDNESDAY. MEAN SOLUTION OF MODELS SUGGEST
NOT BIG THREAT OF CONVECTION THIS PERIOD...THOUGH BEST SHOT WILL BE
PERHAPS MONDAY AS SHORTWAVE MOVES FROM OHIO TO THE MID ATLANTIC
SETTING UP SOME HEIGHT FALLS OVER VIRGINIA...AND WEAK FRONTAL
BOUNDARY PASSING ACROSS. AT THIS TIME WILL MAINTAIN IN THE CHANCE
RANGE FOR POPS.
WILL START TO SEE HUMIDITY ELEVATE ONCE AGAIN WITH BUILDING HEIGHTS
AND LIGHT SOUTHEAST TO SOUTHWEST WINDS IN THE SFC TO LOW LVLS.
HIGHS AND LOWS WILL BE CLOSE TO NORMAL FOR LATE JULY WITH MID 60S
MOUNTAINS TO AROUND 70 PIEDMONT FOR LOWS...AND HIGHS IN THE LOWER TO
MID 80S MOUNTAINS TO AROUND 90 PIEDMONT...INCLUDING ROANOKE CITY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 735 AM EDT THURSDAY...
BASED ON THE LATEST RADAR TRENDS AND WATER VAPOR SATELLITE LOOP...SCATTERED
SHOWERS WILL MOVE ACROSS NORTHERN NORTH CAROLINA AND EXTREME
SOUTHERN VIRGINIA THIS MORNING. HOWEVER...VISIBILITIES WILL REMAIN
VFR....EVEN WITH THE RAIN...AT KLYH AND KDAN.
A SHORT WAVE OVER MISSOURI EARLY THIS MORNING WILL TRACK INTO THE
CAROLINAS BY FRIDAY MORNING. THE ASSOCIATED SHOWERS AND
THUNDERSTORMS OVER KENTUCKY AND TENNESSEE WILL MOVE EAST BRINGING
MORE PRECIPITATION TO SOUTHERN VIRGINIA AND NORTHERN NORTH
CAROLINA BY EARLY THIS AFTERNOON. MODELS IN DECENT AGREEMENT THAT
NORTHERN EDGE OF THE PRECIPITATION CHANCE WILL STAY JUST SOUTH OF
KBLF/KROA/KLYH. KDAN HAS THE BEST CHANCE OF SHOWERS TODAY...WHICH
MAY RESULT IN BRIEF MVFR CONDITIONS. OTHERWISE CEILINGS AND
VISIBILITIES WILL BE VFR. THE FRONT AND DEEP MOISTURE PUSH SOUTH
OUT OF THE AREA TONIGHT.
SURFACE AND LOW LEVEL WINDS BECOME EAST TO NORTHEAST TONIGHT. THIS
WILL BRING MOISTURE UP AGAINST THE EAST SLOPES OF THE
APPALACHIANS. HAVE ADDED MVFR FOG AND CLOUDS IN FOR KROA/KDAN AND
KLYH AFTER MIDNIGHT. MEDIUM CONFIDENCE ON THESE CEILING
HEIGHTS...MAY END UP BEING MUCH LOWER.
EXTENDED AVIATION FORECAST...
FRIDAY THROUGH EARLY NEXT WEEK...HIGH PRESSURE WILL BE THE
DOMINATE WEATHER FEATURE ACROSS THE REGION. MAINLY VFR CONDITIONS
ARE EXPECTED EXCEPT FOR THE POTENTIAL OF LATE NIGHT AND EARLY
MORNING MOUNTAIN VALLEY FOG. ISOLATED SHOWERS AND STORMS CANNOT BE
RULED OUT...ESPECIALLY OVER THE MOUNTAINS ON SUNDAY AFTERNOON.
A WEAK BACKDOOR FRONT MAY ENTER THE REGION LATE SUNDAY NIGHT INTO
MONDAY. THIS WOULD EXPAND SHOWER AND THUNDERSTORMS COVERAGE MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
650 AM EDT THU JUL 23 2015
.SYNOPSIS...
A STALLED FRONT WILL REMAIN SOUTH OF THE REGION FRIDAY. WEAK WAVES
OF LOW PRESSURE WILL TRACK ALONG THE FRONT TODAY AND
TONIGHT...WITH LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST ON
FRIDAY. HIGH PRESSURE WILL STRENGTHEN FRIDAY THROUGH THE
WEEKEND OVER THE MID ATLANTIC REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM EDT THURSDAY...
SHORT WAVE WAS OVER THE MID MISSISSIPPI VALLEY EARLY THIS MORNING ND
WILL TRACK INTO THE CAROLINA BY FRIDAY MORNING. THE ASSOCIATED
PRECIPITATION WAS OVER TENNESSEE AND KENTUCKY AT 08Z. MODELS
BRING THE PRECIPITATION EAST ALONG THE 850 MB FRONT. LITTLE
MOVEMENT OF THE SURFACE FRONT IS EXPECTED TODAY AND INTO THIS
EVENING. SURFACE WINDS WILL BE LIGHT AND VARIABLE UNTIL THE SHORT
WAVE MOVES TO THE EAST...THEN PREVAILING FLOW WILL BE OUT OF THE
NORTHEAST. UNTIL THEN COUNTY WARNING AREA IS IN BETWEEN THE FRONT
OVER THE CAROLINAS AND HIGH PRESSURE OVER THE OHIO VALLEY.
HAVE RAISED PROBABILITY OF PRECIPITATION TO ACCOUNT BASED ON RADAR
TRENDS. HRRR AND LOCAL WRF BRING NEXT BATCH OF PRECIPITATION IN
AFTER 15Z/10AM. MODELS SIMILAR WITH NORTHERN EXTENT OF THE BEST
PROBABILITY OF PRECIPITATION. HIGHER CONVECTIVE AVAILABLE
POTENTIAL ENERGY AND LOWER LIFTED INDEX VALUES WILL BE ALONG AND
SOUTH OF ROUTE 460. WILL KEEP HIGHEST PROBABILITY OF PRECIPITATION
IN THE SOUTHERN HALF OF THE FORECAST AREA THIS AFTERNOON AND
EVENING. THIS ALSO LINES UP WITH PRECIPITABLE WATER VALUES OF 1.5
TO 2.0 INCHES. THIS DEEPER MOISTURE BEGINS TO EXIT SOUTHEAST OUT
OF THE FORECAST AREA LATE TONIGHT. HOWEVER...NORTHEAST WINDS AND
LOW LEVEL MOISTURE WILL KEEP LOW CLOUDS AND FOG IN THE
REGION...ESPECIALLY IN THE EASTERN UPSLOPE AREA OF THE
APPALACHIANS.
DRIER AIR COMING IN THE NORTH ERN COUNTY WARNING AREA AND LESS CLOUD
COVER COMPARED TO MORE CLOUDS IN THE CENTRAL AND SOUTHERN COUNTY
WARNING AREA WILL RESULT IN A LARGE SPREAD OF MINIMUM
TEMPERATURES. DO NOT EXPECT AS MUCH OF A DROP I N HE SOUTH...WHILE
NORTHERN COUNTIES MAY LOWER INTO THE 50S. LOCAL WRF GUIDANCE
LOOKED REASONABLE FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
LOW PRESSURE JUST OFF THE NORTH CAROLINA COAST FRIDAY MORNING WILL
MOVE EAST INTO THE ATLANTIC OCEAN THROUGH THE PERIOD. MEANWHILE HIGH
PRESSURE TO OUR NORTHWEST WILL BUILD SOUTH ON FRIDAY AND MOVE ACROSS
THE MID ATLANTIC REGION INTO SATURDAY NIGHT. THE COMBINATION OF
HEATING...DESTABILIZATION...MOISTURE SFC FLOW OVER HIGHER TERRAIN
SUPPORTS THE MENTION OF ISOLATED TO WIDELY SCATTERED CONVECTION
CROSS THE SOUTHWEST. HIGH TEMPERATURES FRIDAY WILL CLIMB TO NEAR
80 DEGREES IN THE WEST TO THE UPPER 80S IN THE EAST. TAPER OFF
ISOLATED SHOWERS FRIDAY NIGHT BY MIDNIGHT AND ADDED SOME PATCHY
FOG FRIDAY NIGHT INTO SATURDAY MORNING. LOW TEMPERATURES FRIDAY
NIGHT WILL VARY FROM THE MID 50S IN THE MOUNTAINS TO THE MID 60S
IN THE PIEDMONT.
EXPECT A NICE SATURDAY WITH ONLY AN ISOLATED CHANCE OF SHOWERS
ACROSS THE MOUNTAINS. HIGH TEMPERATURES SATURDAY WILL MODERATE INTO
THE LOWER 80S IN THE MOUNTAINS TO AROUND 90 DEGREES IN THE PIEDMONT.
YOU CAN ANTICIPATE DRY WEATHER FOR SATURDAY NIGHT WITH LOW
TEMPERATURES FROM THE LOWER 60S IN THE WEST TO THE MID 60S IN THE
EAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 240 PM EDT WEDNESDAY...
GOING TO UPPER RIDGE START TO LEAN WEST TO EAST ACROSS THE SOUTHERN
PLAINS TO THE APPALACHIANS THIS PERIOD WITH GRADUALLY BUILDING
HEIGHTS. OUR REGION WILL STAY IN A NW FLOW ALOFT THIS SUNDAY THEN
MORE NORTHERLY BY TUESDAY-WEDNESDAY. MEAN SOLUTION OF MODELS SUGGEST
NOT BIG THREAT OF CONVECTION THIS PERIOD...THOUGH BEST SHOT WILL BE
PERHAPS MONDAY AS SHORTWAVE MOVES FROM OHIO TO THE MID ATLANTIC
SETTING UP SOME HEIGHT FALLS OVER VIRGINIA...AND WEAK FRONTAL
BOUNDARY PASSING ACROSS. AT THIS TIME WILL MAINTAIN IN THE CHANCE
RANGE FOR POPS.
WILL START TO SEE HUMIDITY ELEVATE ONCE AGAIN WITH BUILDING HEIGHTS
AND LIGHT SOUTHEAST TO SOUTHWEST WINDS IN THE SFC TO LOW LVLS.
HIGHS AND LOWS WILL BE CLOSE TO NORMAL FOR LATE JULY WITH MID 60S
MOUNTAINS TO AROUND 70 PIEDMONT FOR LOWS...AND HIGHS IN THE LOWER TO
MID 80S MOUNTAINS TO AROUND 90 PIEDMONT...INCLUDING ROANOKE CITY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 135 AM EDT THURSDAY...
EXPECTING INCREASING MID AND HIGH CLOUDS OVER THE MID ATLANTIC
REGION THIS MORNING. UNTIL THE CLOUDS MOVE IN...IFR TO LIFR
VISIBILITIES MAY DEVELOP DUE TO THE FORMATION OF GROUND FOG IN
THE VALLEYS...INCLUDING AT KLWB.
A SHORT WAVE OVER MISSOURI EARLY THIS MORNING WILL TRACK INTO THE
CAROLINAS BY FRIDAY MORNING. THE ASSOCIATED SHOWERS AND
THUNDERSTORMS OVER KENTUCKY AND TENNESSEE WILL MOVE EAST AND REACH
SOUTHERN VIRGINIA AND NORTHERN NORTH CAROLINA BY EARLY THIS
AFTERNOON. MODELS IN DECENT AGREEMENT THAT NORTHERN EDGE OF THE
PRECIPITATION CHANCE WILL STAY JUST SOUTH OF KBLF/KROA/KLYH. KDAN
HAS THE BEST CHANCE OF SHOWERS TODAY...WHICH MAY RESULT IN BRIEF
MVFR CONDITIONS. OTHERWISE CEILINGS AND VISIBILITIES WILL BE VFR.
THE FRONT AND DEEP MOISTURE PUSH SOUTH OUT OF THE AREA TONIGHT.
LOW CONFIDENCE IN THE WINDS THIS FORECAST PACKAGE. WITH SURFACE
FRONT WAVERING CLOSE TO THE AREA...FORECAST OF WIND DIRECTION WAS
CHALLENGING.
EXTENDED AVIATION FORECAST...
AS HIGH PRESSURE BUILDS IN THURSDAY NIGHT...LOOK FOR EAST TO
NORTHEAST WINDS WHICH WILL POOL LOW LEVEL MOISTURE INTO THE
EASTERN SLOPES OF THE APPALACHIANS WITH IFR/MVFR STRATUS AND FOG.
FRIDAY THROUGH EARLY NEXT WEEK...HIGH PRESSURE WILL BE THE
DOMINATE WEATHER FEATURE ACROSS THE REGION. MAINLY VFR CONDITIONS
ARE EXPECTED EXCEPT FOR THE POTENTIAL OF LATE NIGHT AND EARLY
MORNING MOUNTAIN VALLEY FOG. ISOLATED SHOWERS AND STORMS CANNOT
BE RULED OUT...ESPECIALLY OVER THE MOUNTAINS ON SUNDAY AFTERNOON.
A WEAK BACKDOOR FRONT MAY ENTER THE REGION LATE SUNDAY NIGHT INTO
MONDAY. THIS WOULD EXPAND SHOWER AND THUNDERSTORMS COVERAGE MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KK
LONG TERM...WP
AVIATION...AMS/JH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
921 PM MDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 611 PM MDT FRI JUL 24 2015
RADAR AND SATELLITE PICS EARLY THIS EVENING SHOW A FEW VIGOROUS
SHOWERS ALONG A BOUNDARY EXTENDING FROM FAR NORTHWEST LARAMIE
COUNTY EAST INTO THE CENTRAL NEBRASKA PANHANDLE. A FEW SHOWERS ARE
ALSO DEVELOPING ALONG THE PINE RIDGE FROM CENTRAL NIOBRARA COUNTY
INTO NORTHERN SIOUX AND DAWES COUNTIES. WITH SBCAPES ANALYZED AT
GREATER THAN 1000 J/KG IN THESE AREAS...WOULDN`T BE SURPRISED IF
A FEW ISOLATED T-STORMS DEVELOPED FROM THIS ACTIVITY. MIDLEVEL
WINDS ARE PUSHING CONVECTION TO THE EAST-NORTHEAST...SO UPDATED
THE GRIDS TO REFLECT CURRENT ACTIVITY AND DOWNSTREAM TRAJECTORIES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 239 PM MDT FRI JUL 24 2015
FORECAST CHALLENGES DEAL WITH TEMPERATURES AND FIRE WEATHER
CONCERNS THROUGH MONDAY.
CURRENTLY...LATEST WATER VAPOR IMAGERY SHOWING DRY SLOT PRETTY
MUCH RIGHT OVER THE CHEYENNE CWFA THIS AFTERNOON. MONSOONAL
MOISTURE TO THE SOUTH NOT MAKING ANY PROGRESS NORTH THIS AFTERNOON
AND REMAINS OVER THE COLORADO ROCKIES. LATEST RADAR SHOWING
SHOWERS AND THUNDERSTORMS IN THIS MOISTURE...BUT FOR SOUTHEAST
WYOMING...RADAR REMAINS PPINE. HAVE A STALLED OUT BOUNDARY ALONG
THE LARAMIE RANGE THAT SEPARATE VERY DRY AIR WEST AND DEWPOINTS IN
THE UPPER 50S TO LOW 60S EAST OUT INTO THE PANHANDLE.
DO NOT THINK WE WILL SEE MUCH FROM THE MOISTURE TO THE SOUTH
TODAY/THIS EVENING. LATEST HRRR HOURLY RADAR MOSAIC SHOWS SOME
ISOLATED SHOWERS DEVELOPING HERE NEAR CHEYENNE THAT DRIFT OUT INTO
THE PANHANDLE. HAS BEEN SHOWING THIS ALL MORNING...BUT SO
FAR...NOTHING HAS HAPPENED. SO CONFIDENCE NOT ALL THAT HIGH THAT
THIS SOLUTION WILL HAPPEN. CONTINUED A PERSISTENCE FORECAST FOR
THIS AFTERNOON AND EVENING.
LOOKING AT A PRETTY WARM DAY SATURDAY AS 700MB TEMPERATURES CLIMB
TO +18C ACROSS THE WYOMING/COLORADO BORDER. LIKELY OUR WARMEST DAY
OF THE YEAR. DID GO HIGHER THAN MOST GUIDANCE ON TEMPERATURES FOR
SATURDAY AFTERNOON.
VERY SIMILAR CONDITIONS SUNDAY...WITH INCREASING 700MB WINDS OUT
WEST. BY 00Z MONDAY GFS SHOWING 700MB WINDS OUT WEST AT 20-25KTS.
BY SUNDAY EVENING...THEY INCREASE TO 25 TO 30 KTS AND THEN BY
MONDAY MORNING...30 TO 35KTS. DID GO HIGHER ON OVERNIGHT LOWS
SUNDAY NIGHT AS ATMOSPHERE WOULD STAY WELL MIXED WITH POOR
HUMIDITY RECOVERIES. THIS WILL SET THE STAGE FOR A WIDESPREAD
CRITICAL FIRE WEATHER DAY MONDAY.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 239 PM MDT FRI JUL 24 2015
ANOTHER QUITE WARM DAY ACROSS THE CWA MONDAY AHEAD OF A POTENT
UPPER TROF THAT WILL BE MOVING INTO THE NRN ROCKYS. THIS WILL
BRING A RATHER WINDY DAY TO THE WIND-FAVORED AREAS OF SE WYOMING
WITH GUSTS OVER 40 MPH MAKING FOR SOME FIRE WEATHER CONCERNS. AS
THE UPPER TROF EDGES EASTWARD INTO THE NORTHERN PLAINS MONDAY
NIGHT A COLD FRONT WILL MOVE ACROSS THE CWA LEAVING DRY AND MILDER
WEATHER IN ITS WAKE FOR TUESDAY AND WEDNESDAY WITH MAX TEMPS AT OR
A LITTLE BELOW SEASONAL AVERAGES. AFTER THAT THE UPPER FLOW TURNS
GRADUALLY NORTHWESTERLY OVER THE CWA FOR THURSDAY AND FRIDAY
KEEPING A MAINLY DRY PATTERN IN PLACE WITH A GRADUAL WARMUP IN
TEMPS. MONSOONAL FLOW APPEARS IT WILL REMAIN CUT OFF MUCH OF NEXT
WEEK BUT SOME INDICATION IT WILL RETURN NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 919 PM MDT FRI JUL 24 2015
VFR. THROUGH 12Z...MOSTLY CLEAR SKIES NORTH OF A LARAMIE TO
TORRINGTON LINE...SCATTERED TO BROKEN CLOUDS AT OR ABOVE 10000
FEET AGL SOUTH OF THIS LINE.
AFTER 12Z...SCATTERED TO BROKEN CLOUDS AT OR ABOVE 10000 FEET AGL.
WINDS GUSTING 20 TO 30 KNOTS AFTER DAYBREAK ON SATURDAY...THEN
DECREASING EARLY SATURDAY EVENING.
&&
.FIRE WEATHER...
ISSUED AT 239 PM MDT FRI JUL 24 2015
WARM...DRY AND GUSTY EACH AFTERNOON THROUGH THE WEEKEND FOR AREAS
WEST OF THE LARAMIE RANGE AS HIGH PRESSURE DOMINATES THE WEATHER
OUT WEST. EAST OF THE LARAMIE RANGE...A STALLED FRONTAL BOUNDARY
WILL KEEP WINDS EASTERLY THIS AFTERNOON ACROSS THE PANHANDLE AS
WELL AS CONVERSE/NIOBRARA COUNTIES IN EAST CENTRAL WYOMING. WARM
TEMPERATURES AND LOW HUMIDITIES WILL CONTINUE THROUGH SUNDAY WITH
NEAR CRITICAL FIRE WEATHER CONDITIONS ALONG AND WEST OF THE
LARAMIE RANGE. GUIDANCE STILL SHOWS AN UNUSUALLY STRONG LOW
PRESSURE SYSTEM MOVING INTO WESTERN MONTANA SUNDAY NIGHT INTO
MONDAY. WE ARE STILL LOOKING AT A WIDESPREAD STRONG WIND EVENT
MONDAY. POOR OVERNIGHT HUMIDITY RECOVERIES SUNDAY NIGHT/MONDAY
MORNING WILL START HUMIDITIES OFF LOW MONDAY MORNING. AS THE WINDS
INCREASE...WE COULD SEE WIDESPREAD CRITICAL FIRE WEATHER
CONDITIONS AS EARLY AS 9AM MONDAY...PERSISTING THROUGH SUNSET.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...RJM
SHORT TERM...GCC
LONG TERM...RE
AVIATION...RUBIN
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
611 PM MDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 611 PM MDT FRI JUL 24 2015
RADAR AND SATELLITE PICS EARLY THIS EVENING SHOW A FEW VIGOROUS
SHOWERS ALONG A BOUNDARY EXTENDING FROM FAR NORTHWEST LARAMIE
COUNTY EAST INTO THE CENTRAL NEBRASKA PANHANDLE. A FEW SHOWERS ARE
ALSO DEVELOPING ALONG THE PINE RIDGE FROM CENTRAL NIOBRARA COUNTY
INTO NORTHERN SIOUX AND DAWES COUNTIES. WITH SBCAPES ANALYZED AT
GREATER THAN 1000 J/KG IN THESE AREAS...WOULDN`T BE SURPRISED IF
A FEW ISOLATED T-STORMS DEVELOPED FROM THIS ACTIVITY. MIDLEVEL
WINDS ARE PUSHING CONVECTION TO THE EAST-NORTHEAST...SO UPDATED
THE GRIDS TO REFLECT CURRENT ACTIVITY AND DOWNSTREAM TRAJECTORIES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 239 PM MDT FRI JUL 24 2015
FORECAST CHALLENGES DEAL WITH TEMPERATURES AND FIRE WEATHER
CONCERNS THROUGH MONDAY.
CURRENTLY...LATEST WATER VAPOR IMAGERY SHOWING DRY SLOT PRETTY
MUCH RIGHT OVER THE CHEYENNE CWFA THIS AFTERNOON. MONSOONAL
MOISTURE TO THE SOUTH NOT MAKING ANY PROGRESS NORTH THIS AFTERNOON
AND REMAINS OVER THE COLORADO ROCKIES. LATEST RADAR SHOWING
SHOWERS AND THUNDERSTORMS IN THIS MOISTURE...BUT FOR SOUTHEAST
WYOMING...RADAR REMAINS PPINE. HAVE A STALLED OUT BOUNDARY ALONG
THE LARAMIE RANGE THAT SEPARATE VERY DRY AIR WEST AND DEWPOINTS IN
THE UPPER 50S TO LOW 60S EAST OUT INTO THE PANHANDLE.
DO NOT THINK WE WILL SEE MUCH FROM THE MOISTURE TO THE SOUTH
TODAY/THIS EVENING. LATEST HRRR HOURLY RADAR MOSAIC SHOWS SOME
ISOLATED SHOWERS DEVELOPING HERE NEAR CHEYENNE THAT DRIFT OUT INTO
THE PANHANDLE. HAS BEEN SHOWING THIS ALL MORNING...BUT SO
FAR...NOTHING HAS HAPPENED. SO CONFIDENCE NOT ALL THAT HIGH THAT
THIS SOLUTION WILL HAPPEN. CONTINUED A PERSISTENCE FORECAST FOR
THIS AFTERNOON AND EVENING.
LOOKING AT A PRETTY WARM DAY SATURDAY AS 700MB TEMPERATURES CLIMB
TO +18C ACROSS THE WYOMING/COLORADO BORDER. LIKELY OUR WARMEST DAY
OF THE YEAR. DID GO HIGHER THAN MOST GUIDANCE ON TEMPERATURES FOR
SATURDAY AFTERNOON.
VERY SIMILAR CONDITIONS SUNDAY...WITH INCREASING 700MB WINDS OUT
WEST. BY 00Z MONDAY GFS SHOWING 700MB WINDS OUT WEST AT 20-25KTS.
BY SUNDAY EVENING...THEY INCREASE TO 25 TO 30 KTS AND THEN BY
MONDAY MORNING...30 TO 35KTS. DID GO HIGHER ON OVERNIGHT LOWS
SUNDAY NIGHT AS ATMOSPHERE WOULD STAY WELL MIXED WITH POOR
HUMIDITY RECOVERIES. THIS WILL SET THE STAGE FOR A WIDESPREAD
CRITICAL FIRE WEATHER DAY MONDAY.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 239 PM MDT FRI JUL 24 2015
ANOTHER QUITE WARM DAY ACROSS THE CWA MONDAY AHEAD OF A POTENT
UPPER TROF THAT WILL BE MOVING INTO THE NRN ROCKYS. THIS WILL
BRING A RATHER WINDY DAY TO THE WIND-FAVORED AREAS OF SE WYOMING
WITH GUSTS OVER 40 MPH MAKING FOR SOME FIRE WEATHER CONCERNS. AS
THE UPPER TROF EDGES EASTWARD INTO THE NORTHERN PLAINS MONDAY
NIGHT A COLD FRONT WILL MOVE ACROSS THE CWA LEAVING DRY AND MILDER
WEATHER IN ITS WAKE FOR TUESDAY AND WEDNESDAY WITH MAX TEMPS AT OR
A LITTLE BELOW SEASONAL AVERAGES. AFTER THAT THE UPPER FLOW TURNS
GRADUALLY NORTHWESTERLY OVER THE CWA FOR THURSDAY AND FRIDAY
KEEPING A MAINLY DRY PATTERN IN PLACE WITH A GRADUAL WARMUP IN
TEMPS. MONSOONAL FLOW APPEARS IT WILL REMAIN CUT OFF MUCH OF NEXT
WEEK BUT SOME INDICATION IT WILL RETURN NEXT WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 529 PM MDT FRI JUL 24 2015
VFR. SCATTERED TO BROKEN CLOUDS AT OR ABOVE 8000 FEET AGL.
WINDS GUSTING 20 TO 30 KNOTS AFTER DAYBREAK SATURDAY.
&&
.FIRE WEATHER...
ISSUED AT 239 PM MDT FRI JUL 24 2015
WARM...DRY AND GUSTY EACH AFTERNOON THROUGH THE WEEKEND FOR AREAS
WEST OF THE LARAMIE RANGE AS HIGH PRESSURE DOMINATES THE WEATHER
OUT WEST. EAST OF THE LARAMIE RANGE...A STALLED FRONTAL BOUNDARY
WILL KEEP WINDS EASTERLY THIS AFTERNOON ACROSS THE PANHANDLE AS
WELL AS CONVERSE/NIOBRARA COUNTIES IN EAST CENTRAL WYOMING. WARM
TEMPERATURES AND LOW HUMIDITIES WILL CONTINUE THROUGH SUNDAY WITH
NEAR CRITICAL FIRE WEATHER CONDITIONS ALONG AND WEST OF THE
LARAMIE RANGE. GUIDANCE STILL SHOWS AN UNUSUALLY STRONG LOW
PRESSURE SYSTEM MOVING INTO WESTERN MONTANA SUNDAY NIGHT INTO
MONDAY. WE ARE STILL LOOKING AT A WIDESPREAD STRONG WIND EVENT
MONDAY. POOR OVERNIGHT HUMIDITY RECOVERIES SUNDAY NIGHT/MONDAY
MORNING WILL START HUMIDITIES OFF LOW MONDAY MORNING. AS THE WINDS
INCREASE...WE COULD SEE WIDESPREAD CRITICAL FIRE WEATHER
CONDITIONS AS EARLY AS 9AM MONDAY...PERSISTING THROUGH SUNSET.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...RJM
SHORT TERM...GCC
LONG TERM...RE
AVIATION...RUBIN
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
531 PM MDT FRI JUL 24 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 239 PM MDT FRI JUL 24 2015
FORECAST CHALLENGES DEAL WITH TEMPERATURES AND FIRE WEATHER
CONCERNS THROUGH MONDAY.
CURRENTLY...LATEST WATER VAPOR IMAGERY SHOWING DRY SLOT PRETTY
MUCH RIGHT OVER THE CHEYENNE CWFA THIS AFTERNOON. MONSOONAL
MOISTURE TO THE SOUTH NOT MAKING ANY PROGRESS NORTH THIS AFTERNOON
AND REMAINS OVER THE COLORADO ROCKIES. LATEST RADAR SHOWING
SHOWERS AND THUNDERSTORMS IN THIS MOISTURE...BUT FOR SOUTHEAST
WYOMING...RADAR REMAINS PPINE. HAVE A STALLED OUT BOUNDARY ALONG
THE LARAMIE RANGE THAT SEPARATE VERY DRY AIR WEST AND DEWPOINTS IN
THE UPPER 50S TO LOW 60S EAST OUT INTO THE PANHANDLE.
DO NOT THINK WE WILL SEE MUCH FROM THE MOISTURE TO THE SOUTH
TODAY/THIS EVENING. LATEST HRRR HOURLY RADAR MOSAIC SHOWS SOME
ISOLATED SHOWERS DEVELOPING HERE NEAR CHEYENNE THAT DRIFT OUT INTO
THE PANHANDLE. HAS BEEN SHOWING THIS ALL MORNING...BUT SO
FAR...NOTHING HAS HAPPENED. SO CONFIDENCE NOT ALL THAT HIGH THAT
THIS SOLUTION WILL HAPPEN. CONTINUED A PERSISTENCE FORECAST FOR
THIS AFTERNOON AND EVENING.
LOOKING AT A PRETTY WARM DAY SATURDAY AS 700MB TEMPERATURES CLIMB
TO +18C ACROSS THE WYOMING/COLORADO BORDER. LIKELY OUR WARMEST DAY
OF THE YEAR. DID GO HIGHER THAN MOST GUIDANCE ON TEMPERATURES FOR
SATURDAY AFTERNOON.
VERY SIMILAR CONDITIONS SUNDAY...WITH INCREASING 700MB WINDS OUT
WEST. BY 00Z MONDAY GFS SHOWING 700MB WINDS OUT WEST AT 20-25KTS.
BY SUNDAY EVENING...THEY INCREASE TO 25 TO 30 KTS AND THEN BY
MONDAY MORNING...30 TO 35KTS. DID GO HIGHER ON OVERNIGHT LOWS
SUNDAY NIGHT AS ATMOSPHERE WOULD STAY WELL MIXED WITH POOR
HUMIDITY RECOVERIES. THIS WILL SET THE STAGE FOR A WIDESPREAD
CRITICAL FIRE WEATHER DAY MONDAY.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 239 PM MDT FRI JUL 24 2015
ANOTHER QUITE WARM DAY ACROSS THE CWA MONDAY AHEAD OF A POTENT
UPPER TROF THAT WILL BE MOVING INTO THE NRN ROCKYS. THIS WILL
BRING A RATHER WINDY DAY TO THE WIND-FAVORED AREAS OF SE WYOMING
WITH GUSTS OVER 40 MPH MAKING FOR SOME FIRE WEATHER CONCERNS. AS
THE UPPER TROF EDGES EASTWARD INTO THE NORTHERN PLAINS MONDAY
NIGHT A COLD FRONT WILL MOVE ACROSS THE CWA LEAVING DRY AND MILDER
WEATHER IN ITS WAKE FOR TUESDAY AND WEDNESDAY WITH MAX TEMPS AT OR
A LITTLE BELOW SEASONAL AVERAGES. AFTER THAT THE UPPER FLOW TURNS
GRADUALLY NORTHWESTERLY OVER THE CWA FOR THURSDAY AND FRIDAY
KEEPING A MAINLY DRY PATTERN IN PLACE WITH A GRADUAL WARMUP IN
TEMPS. MONSOONAL FLOW APPEARS IT WILL REMAIN CUT OFF MUCH OF NEXT
WEEK BUT SOME INDICATION IT WILL RETURN NEXT WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 529 PM MDT FRI JUL 24 2015
VFR. SCATTERED TO BROKEN CLOUDS AT OR ABOVE 8000 FEET AGL.
WINDS GUSTING 20 TO 30 KNOTS AFTER DAYBREAK SATURDAY.
&&
.FIRE WEATHER...
ISSUED AT 239 PM MDT FRI JUL 24 2015
WARM...DRY AND GUSTY EACH AFTERNOON THROUGH THE WEEKEND FOR AREAS
WEST OF THE LARAMIE RANGE AS HIGH PRESSURE DOMINATES THE WEATHER
OUT WEST. EAST OF THE LARAMIE RANGE...A STALLED FRONTAL BOUNDARY
WILL KEEP WINDS EASTERLY THIS AFTERNOON ACROSS THE PANHANDLE AS
WELL AS CONVERSE/NIOBRARA COUNTIES IN EAST CENTRAL WYOMING. WARM
TEMPERATURES AND LOW HUMIDITIES WILL CONTINUE THROUGH SUNDAY WITH
NEAR CRITICAL FIRE WEATHER CONDITIONS ALONG AND WEST OF THE
LARAMIE RANGE. GUIDANCE STILL SHOWS AN UNUSUALLY STRONG LOW
PRESSURE SYSTEM MOVING INTO WESTERN MONTANA SUNDAY NIGHT INTO
MONDAY. WE ARE STILL LOOKING AT A WIDESPREAD STRONG WIND EVENT
MONDAY. POOR OVERNIGHT HUMIDITY RECOVERIES SUNDAY NIGHT/MONDAY
MORNING WILL START HUMIDITIES OFF LOW MONDAY MORNING. AS THE WINDS
INCREASE...WE COULD SEE WIDESPREAD CRITICAL FIRE WEATHER
CONDITIONS AS EARLY AS 9AM MONDAY...PERSISTING THROUGH SUNSET.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...GCC
LONG TERM...RE
AVIATION...RUBIN
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1157 PM MDT WED JUL 22 2015
.UPDATE...
ISSUED AT 906 PM MDT WED JUL 22 2015
THUNDERSTORM ACTIVITY HAS DECREASED SUBSTANTIALLY OVER THE LAST
FEW HOURS. WILL SEE ISOLATED SHOWER ACTIVITY CONTINUE THIS EVENING
BUT BY MIDNIGHT MOST ALL SHOWERS SHOULD HAVE DISSIPATED. COULD
SEE A FEW SHOWERS LINGER INTO THE NW PORTIONS OF THE FORECAST AREA
BUT NOT EXPECTING MORE THAN A FEW SPRINKLES.
UPDATE ISSUED AT 442 PM MDT WED JUL 22 2015
UPDATED THUNDERSTORM CHANCES TO INCLUDE THE NORTHERN NEBRASKA
PANHANDLE AND ALL OF EAST CENTRAL WYOMING FOR EARLY THIS EVENING.
CURRENTLY A LINE OF THUNDERSTORMS IS MAKING ITS INTO THAT AREA AND
WITH A VERY UNSTABLE AIRMASS AND INCREASING SURFACE BASED CAPE
VALUES...STORMS SHOULD CONTINUE TO PROPAGATE ACROSS THAT AREA OVER
THE NEXT SEVERAL HOURS. WITH LIMITED SHEAR SEVERE THUNDERSTORM
THREAT IS ON THE LOW SIDE BUT HIGHER CAPE VALUES DO SUPPORT SOME
STRONGER PULSE THUNDERSTORMS. MARGINAL SEVERE HAIL...HEAVY RAIN
AND WIND GUSTS TO 60 MPH CAN NOT BE RULED OUT OVER THROUGH EARLY
EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 230 PM MDT WED JUL 22 2015
LATEST WATER VAPOR DEPICTING LAST OF MONSOONAL MOISTURE ACROSS
SOUTHEAST WYOMING THIS AFTERNOON. SIGNIFICANT DRYING ON WATER
VAPOR OVER MOST OF COLORADO IS INCHING EVER SO SLOWLY NORTHWARD
TOWARDS THE SOUTHERN WYOMING BORDER. SEEING SCATTERED SHOWERS AND
THUNDERSTORMS ON AREA RADAR THIS AFTERNOON...MAINLY ALONG THE
WYOMING/COLORADO BORDER AND MOUNTAIN RANGES TO OUR WEST AND NORTH.
SURFACE BASED CAPE OFF THE MESOANALYST PAGE SHOWING RIGHT AROUND
500 J/KG WHERE THESE THUNDERSTORMS ARE FORMING...SO DO NOT EXPECT
ANY SEVERE TSTMS FROM THESE. BETTER INSTABILITY ACROSS THE
PANHANDLE WHERE CAPES ARE RUNNING 1500-2500 J/KG AT 1 PM THIS
AFTERNOON. DEWPOINTS ACROSS THE PANHANDLE NEAR 60 FOR
ALLIANCE...SCOTTSBLUFF AND SIDNEY. WILL NEED TO WATCH THUNDERSTORM
EVOLUTION AS THE AFTERNOON PROGRESSES OUT THAT WAY.
LATEST HRRR FORECAST RADAR SHOWING THE POSSIBILITY OF A FEW STRONG
STORMS MAKING IT INTO THIS MORE UNSTABLE AIR IN THE PANHANDLE THIS
AFTERNOON AROUND 00Z. CAN NOT RULE OUT ONE OR TWO SEVERE STORMS
FOR THIS EVENING OUT THAT WAY. SHEAR OUT THAT WAY ALMOST
NONEXISTENT...WITH LONG SKINNY CAPE PROFILES...SO THINK THE MORE
PROMINENT HAZARD WOULD BE HEAVY RAIN. ATTENTION TURNS TO ELEVATED
FIRE CONDITIONS THURSDAY AND FRIDAY.
GFS FORECASTING THE LOW PRESSURE SYSTEM CURRENTLY OVER SOUTHERN
BRITISH COLUMBIA...TO TRACK INTO NORTHERN MONTANA THURSDAY. THIS
IS A FAVORABLE WIND PATTERN FOR SOUTHEAST WYOMING. AS A
RESULT...WESTERLY WINDS BEGIN TO INCREASE OUT ACROSS CARBON AND
ALBANY COUNTIES. GFS 700MB WINDS OF 30-35KTS THURSDAY AFTERNOON.
LOOKS LIKE THE AREA WILL MIX UP TO AT LEAST 580MBS OUT THAT WAY.
NAM WINDS UP AROUND THAT LEVEL FORECAST AT 35-40KTS...SO CARBON
AND ALBANY COUNTIES COULD BE SEEING WINDS GUSTING TO 40MPH OR
MORE. FORTUNATELY...FUELS ARE STILL BEING REPORTED AS NOT READY
FOR MOST FIRE ZONES...SO RED FLAG WARNINGS ARE NOT EXPECTED.
WINDS EASE SOME FRIDAY AS THE LOW TRACKS EAST INTO SOUTHERN
ALBERTA CANADA AND EASTWARD. LESS CLOUD COVERAGE AND 700MB
TEMPERATURES CLIMBING TO +16C FRIDAY AND SATURDAY SHOULD LEAD TO
SOME VERY WARM TEMPERATURES. DID GO OVER GUIDANCE ON HIGHS FOR
THURSDAY AND FRIDAY.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 230 PM MDT WED JUL 22 2015
UPPER HIGH CENTERED OVER THE SOUTHERN PLAINS/HIGH PLAINS WILL
MEANDER OVER THAT GENERAL AREA THROUGH THIS PERIOD. THE CWA WILL
RESIDE ON THE NORTHERN PERIPHERY OF THE HIGH WITH WARM AND MAINLY
DRY WEATHER EXPECTED OVERALL...WITH THE WARMEST DAYS SATURDAY
THROUGH MONDAY. A COUPLE DISTURBANCES SHOULD ROTATE OVER THE HIGH
AND MAY BRING SOME CONVECTION TO PARTS OF THE CWA...MAINLY SUNDAY
AND WEDNESDAY. MONSOONAL MOISTURE LOOKS LIKE IT WILL REMAIN CUT
OFF FOR THE MOST PART. AN UPPER LOW WILL MOVE EAST ACROSS THE
SOUTHERN CANADIAN PRAIRIES MONDAY THROUGH TUESDAY AND SHOULD DRIVE
A COOL FRONT ACROSS THE CWA MONDAY NIGHT WITH TEMPS LOWERING
CLOSER TO SEASONAL AVERAGES FOR TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1153 PM MDT WED JUL 22 2015
NO AVIATION CONCERNS TONIGHT WITH LIGHT WINDS AND CLEAR SKIES FOR
MOST OF THE FORECAST AREA. A FEW SHOWERS WILL BE POSSIBLE INTO
CENTRAL PORTIONS OF WYOMING BUT WILL HAVE MINIMAL TO NO IMPACT ON
AVIATION. WEST TO SOUTHWEST WINDS WILL BECOME GUSTY ACROSS
SOUTHEAST WYOMING THURSDAY AFTERNOON. GUSTS AROUND 25 MPH INTO THE
PLAINS WITH GUSTS UP TO 35 MPH INTO SOUTH CENTRAL WYOMING.
&&
.FIRE WEATHER...
ISSUED AT 230 PM MDT WED JUL 22 2015
A DRIER AND MORE WINDY PERIOD AHEAD FOR THE REMAINDER OF THE WEEK
AFTER SHOWERS AND THUNDERSTORMS END TODAY. MONSOONAL MOISTURE
FORECAST TO BE SUPPRESSED SOUTH AND EAST BY THURSDAY. LOW PRESSURE
TRACKING THROUGH NORTHERN MONTANA THURSDAY WILL AID IN INCREASING
WESTERLY TO SOUTHWESTERLY WINDS...ESPECIALLY WEST OF THE LARAMIE
RANGE THURSDAY AND FRIDAY. ELEVATED FIRE WEATHER CONCERNS WITH
THESE WINDS AND AFTERNOON HUMIDITIES FALLING TO 15 PERCENT BOTH
AFTERNOONS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...SML
SHORT TERM...GCC
LONG TERM...RE
AVIATION...SML
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS TUCSON AZ
915 PM MST FRI JUL 24 2015
.SYNOPSIS...ISOLATED SHOWERS AND THUNDERSTORMS THIS WEEKEND MAINLY
SOUTH AND EAST OF TUCSON. PATTERN BECOME A LITTLE MORE FAVORABLE
NEXT WEEK FOR AN UPSWING IN DAILY THUNDERSTORM ACTIVITY.
&&
.DISCUSSION...MAIN ACTION THIS EVENING HAS BEEN ACROSS COCHISE
COUNTY WHERE THERE HAVE BEEN SEVERAL CLUSTER OF STRONG THUNDERSTORMS
ALONG WITH AREAS OF HEAVY RAIN. AS OF 9 PM...SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS ACROSS NORTHERN/WESTERN COCHISE AND SOUTHERN
GRAHAM COUNTIES ARE GRADUALLY MOVING TO THE NORTHWEST. THE 02Z RUN
OF THE HRRR HAS THIS ACTIVITY MOVING INTO FAR EASTERN PIMA COUNTY BY
10 PM AND THEN WEAKENING AND THEN INTO EASTERN PINAL COUNTY BY 11
PM. EARLIER THIS EVENING MADE SOME SLIGHT ADJUSTMENTS TO THE EVENING
FORECAST BASED ON ABOVE THINKING WITH LITTLE ACTIVITY MOVING INTO
THE TUCSON VALLEY BUT BETTER CHANCE IN THE RINCON/CATALINA MOUNTAINS
THRU MIDNIGHT.
AREAL COVERAGE OF THUNDERSTORMS ON SATURDAY WILL BE KINDA SIMILAR TO
TODAY WITH LESS ACTIVITY ON SUNDAY AS DRIER AIR PUSHES IN FROM THE W.
&&
.AVIATION...VALID THRU 26/03Z.
SCT-BKN CLOUDS AT 5-8K FT AGL WITH ISO-SCT SHRA/TSRA THROUGH
25/09Z...MAINLY E AND NE OF KTUS. OUTSIDE OF STORM INFLUENCE...SFC
WINDS WILL FOLLOW NORMAL DIURNAL TRENDS WITH SPEEDS MAINLY LESS THAN
12 KTS. AS DRIER AIR MOVES IN SATURDAY... COVERAGE OF ISO-SCT
SHRA/TSRA WILL MAINLY BE TO THE SOUTH AND EAST OF KTUS. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...A SLIGHT DRYING TREND THIS WEEKEND WILL LIMIT
PRECIPITATION A BIT...WITH ISOLATED TO SCATTERED ACTIVITY OCCURRING
MAINLY ACROSS SOUTHEASTERN AREAS AND IN THE WHITE MOUNTAINS. MORE
WIDESPREAD SHOWERS AND THUNDERSTORMS ARE THEN LIKELY ESPECIALLY
TUESDAY THROUGH THURSDAY IN CONJUNCTION WITH ANOTHER INFLUX OF
MOISTURE FROM THE SOUTHEAST. 20-FT WINDS WILL GENERALLY BE TERRAIN
DRIVEN AND LESS THAN 15 MPH...WITH THE EXCEPTION OF SOME AFTERNOON
GUSTINESS DUE TO DAYTIME HEATING. AREAS IN AND AROUND STRONGER
THUNDERSTORMS COULD SEE VARIABLE WIND GUSTS OF 40 TO 45 MPH.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
!--NOT SENT--!
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
445 AM EDT SAT JUL 25 2015
.DISCUSSION...
TODAY-TONIGHT...
SFC LOW OFF THE CAROLINA COAST WILL CRANK A WEAK FRONTAL TROF AXIS
OVER THE FL PANHANDLE INTO THE NRN PENINSULA THRU THE DAY. AS THE AXIS
NUDGES INTO THE AREA...WINDS ALONG AND N OF THE I-4 CORRIDOR WILL VEER
TO THE N/NW THRU MIDDAY...THEN TO THE N/NE THIS AFTN. S OF I-4...A
STEADY W/SW FLOW WILL PREVAIL. THE USAF 915HZ CAPE PROFILER SHOWING
SIGNS OF THE APPROACHING FRONT AS THE BRISK W/SW FLOW THAT PREVAILED
THRU THE H100-H70 LYR ON FRIDAY HAVE BECOME LIGHT AND VARIABLE THRU
3KFT...AND W/NW 5-10KTS THRU THE 3KFT-10KFT LYR. THE 00Z SOUNDINGS
CONTINUE TO MEASURE HI PWAT AIR BTWN 2.2" AND 2.4" OVER CENTRAL/N FL.
STATEWIDE...WHILE LATEST RAP ANALYSIS SHOWS H100-H70 MEAN RH BTWN
80-90PCT...H85-H50 RH BTWN 70-80PCT.
SEA BREEZE FORMATION ALONG THE BREVARD/VOLUSIA COUNTY COAST DUE TO THE
WEAKENING WRLY FLOW...PGRAD ALONG THE TREASURE COAST SUGGESTS ANY SEA
BREEZE WILL BE LIMITED N OF SEBASTIAN INLET. EVEN SO...STORM STRENGTH
ONCE AGAIN WILL BE LIMITED TODAY AS WARM TEMPS ALOFT CONTINUE TO LIMIT
DEEP LYR THERMODYNAMIC INSTABILITY...H70 TEMPS BTWN 8-9C AND H50
TEMPS ARND -5C ARE YIELDING LAPSE RATES ARND 5C/KM THRU THE LYR. WEAK
CAPPING ARND THE H85 LVL WILL NOT BE ABLE TO SUPPRESS CONVECTION ONCE
CONVECTIVE TEMP TRIGGERS ARE REACHED (U80S-L90S)...WHICH WILL LEAVE
LITTLE OPPORTUNITY FOR THE AIRMASS TO BUILD UP SUFFICIENT ENERGY TO
BECOME EXPLOSIVE.
PRESENCE OF THE APPROACHING TROF AXIS HAS ENHANCED THE MID LVL VORT
FIELDS ACRS CENTRAL FL...PROVIDING MID LVL DYNAMIC LIFT. UPR LVLS ARE
WEAKLY AS THE PENINSULA IS UNDER THE ASCENDING RIGHT REAR QUAD OF A
40-50KT NERLY JET STREAK OVER CUBA AND THE CENTRAL BAHAMAS. WILL GO
WITH 70/80 POPS AS THE HI PWAT VALUES AND TROF ENHANCED INSTABILITY
SUPPORTS NMRS/WDSPRD PRECIP COVERAGE...BCMG 30-40PCT CHC AFT SUNSET
CONTG THRU MIDNIGHT. THREAT FOR LCL FLOODING WILL CONTINUE AS RECENT
RAINFALL HAS PUSHED ERC VALUES BLO 20 OVER MUCH OF THE CWA...INTO THE
SINGLE DIGITS IN LAKE/ST. LUCIE/MARTIN COUNTIES.
BULK OF ANY RAINFALL EXPECTED AFT PEAK HEATING HRS...BUT INCREASING
CLOUD COVER/PRECIP COVERAGE WILL KEEP MAX TEMPS WITHIN A DEG OR TWO
OF CLIMO AVG (L90S). SFC DEWPOINTS IN THE M70S AREAWIDE SUGGEST ABV
AVG MIN TEMPS IN THE M/U70.
SUN/SUN NIGHT...
MODELS ARE LEANING TOWARDS KEEPING THE TROUGH AXIS AND ASSOCIATED
SURFACE BOUNDARY A LITTLE FURTHER SOUTH AND WEST FOR THE LATTER HALF
OF THE WEEKEND. THIS WOULD CONTINUE TO SHIFT THE DEEPEST MOISTURE
SOUTHWARD AND ALLOW THE ONSHORE COMPONENT ON THE NORTH SIDE OF THE
TROUGH/BOUNDARY TO OVERSPREAD FURTHER SOUTH...POSSIBLY TO THE SPACE
COAST. THE FURTHER SOUTH THE BOUNDARY IS ABLE TO SLIP...THE MORE DRY
AIR THE ONSHORE FLOW CAN ADVECT INTO THE REGION. FOR NOW...MODELS
SHOW BEST RAIN CHANCES ACROSS THE TREASURE COAST INTO
OKEECHOBEE/OSCEOLA. LOWEST CHANCES WILL BE ACROSS VOLUSIA/NORTHERN
LAKE WHERE ONSHORE COMPONENT WILL BE A LITTLE STRONGER AND AIRMASS
SLIGHTLY DRIER...SHIFTING BEST RAIN CHANCES FURTHER INLAND AND WEST.
SEVERE THREAT REMAINS LOW DUE TO WARM TEMPS ALOFT BUT THREAT FOR
LOCALLY HEAVY RAINFALL WILL CONTINUE.
MON-WED...
UPPER LEVEL TROUGH AND SURFACE BOUNDARY SLOWLY ELONGATE AND WEAKEN
ACROSS THE FL PENINSULA EARLY IN THE WEEK WITH THE ECMWF STILL
CONSIDERABLY STRONGER IN HOLDING ONTO LOWER HEIGHTS OVER THE
PENINSULA. OVERALL THE LOW LEVEL BOUNDARY...OR ITS REMNANTS...WILL
MEANDER OVER THE PENINSULA THROUGH MID WEEK. RAIN CHANCES ON THE
NORTH SIDE OF THE BOUNDARY..GENERALLY NORTH OF THE CAPE...WILL BE
LOWER IN STRONGER ONSHORE FLOW AND A DRIER AIRMASS. BEST RAIN
CHANCES CURRENTLY ON MONDAY WITH MOST LOCATIONS 60-70% AND THEN
LOWER COVERAGE INTO TUESDAY AND WEDNESDAY AT 40-50% AS SOME OVERALL
DRYING WORKS INTO THE AREA AND THE TROUGH FURTHER WASHES OUT.
THU-FRI...
BETTER MODEL AGREEMENT ON THE 25/00Z RUNS IN THE LATE WEEK SYNOPTIC
PATTERN THOUGH DIFFERENCES REMAINS. GFS CONTINUES TO BE MUCH FASTER
IN REBUILDING THE LOW WESTERN ATLANTIC RIDGE BACK ACROSS THE
PENINSULA WHILE ALSO SEEING RISING UPPER LEVEL HEIGHTS AS RIDING
BUILDS IN FROM THE ATLANTIC. THE ECMWF IS NOW ON A SIMILAR TRACK...
BUT HOLDS ONTO A CUT OFF LOW OVER THE STATE A DAY LONGER AND KEEP
PATTERN A LITTLE MORE UNSETTLED. OVERALL TREND LOOKS TO BE FOR POPS
TO TREND TOWARDS CLIMATOLOGICAL AVERAGES AROUND 40% BY THE END OF
THE WEEK THROUGH BRISK OFFSHORE FLOW WILL CONTINUE TO PUSH ACTIVITY
BACK TOWARDS THE EASTERN SIDE OF THE PENINSULA.
&&
.AVIATION...THRU 26/12Z
FRNTL TROF OVER N FL WILL DRIFT INTO THE VCNTY OF THE I-4 CORRIDOR
TODAY. SFC WNDS N OF KTIX-KISM BCMG LIGHT N/NW THRU MIDDAY...THEN
LIGHT TO GENTLE N/NE IN THE AFTN. W/SW WINDS WILL CONTINUE S OF KTIX-
KISM...LIGHT TO GENTLE KMLB-KVRB...GENTLE TO MODERATE KFPR-KSUA DUE
TO A TIGHTER SFC PGRAD OVER S FL. CHC MVFR SHRAS ALL SITES THRU BTWN
25/12Z-25/16Z...NMRS TO WDSPRD MVFR SHRAS/SCT IFR TSRAS ALL SITES
BTWN 24/16Z-24/24Z...SLGT CHC +TSRAS WITH SFC WND G35KTS. BTWN
25/00Z-25/04Z...CHC MVFR SHRAS/SLGT CHC IFR TSRAS ALL SITES.
&&
.MARINE...
TODAY-TONIGHT...THE COMBINATION OF LIGHT/GENTLE WINDS N OF SEBASTIAN
INLET TO THE STEADY OFFSHORE FLOW S OF THE INLET WILL KEEP SEAS AOB
2FT NEARSHORE AND 2-3FT OFFSHORE. CHOPPY WIND WAVES THRU MIDDAY DUE
TO THE OFFSHORE WINDS WITH DOMINANT PDS BTWN 4-5SECS. PDS WILL
LENGTHEN TO 6-8SEC FROM CAPE CANAVERAL NWD AFT SUNSET AS THE ONSHORE
FLOW DAMPENS OUT THE WIND CHOP. SCT/NMRS OFFSHORE MOVING SHRAS/TSRAS
WITH STRONG SFC WND GUSTS WILL BE THE PRIMARY MARINE HAZARD TODAY.
SUNDAY-MONDAY...BOUNDARY DRAPED ACROSS REGION WILL RESULT IN EAST-
NORTHEAST WINDS NORTH OF THE CAPE AND SOUTHWEST WINDS ALONG THE
TREASURE COAST SOUTH OF THE BOUNDARY...THOUGH EXACTLY WHERE WIND
FIELD SETS UP WILL DEPEND ON BOUNDARY. BOUNDARY LIFTS NORTH BY LATE
MONDAY WITH SOUTHWEST WINDS OVERSPREADING OVER ALL THE WATERS INTO
MONDAY NIGHT. SEAS 2-3FT WITH UP TO 4FT WELL OFFSHORE. MAIN BOATING
CONCERN WILL REMAIN OFFSHORE MOVING THUNDERSTORMS THROUGH THE PERIOD.
TUESDAY-WEDNESDAY...BOUNDARY MEANDERS NEAR VOLUSIA COUNTY RESULTING
IN LIGHT AND VARIABLE WINDS OVER THE ADJACENT WATERS WITH SOUTH-
SOUTHWEST WINDS AROUND 10KTS ELSEWHERE OVER THE LOCAL ATLANTIC. SEAS
CONTINUE AROUND 2-3FT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 90 77 88 76 / 70 30 50 30
MCO 90 75 92 75 / 70 30 70 30
MLB 89 76 90 75 / 70 40 60 40
VRB 90 75 90 74 / 70 40 60 40
LEE 90 76 92 76 / 70 30 60 30
SFB 91 75 91 75 / 70 30 60 30
ORL 90 76 91 76 / 70 30 70 30
FPR 90 75 90 74 / 80 40 70 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...BRAGAW
LONG TERM/IMPACT WX...MOSES
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
327 AM EDT SAT JUL 25 2015
.SYNOPSIS...
THE REGION WILL REMAIN BETWEEN WEAK HIGH PRESSURE TO THE NORTH
AND A STATIONARY FRONT AND LOW PRESSURE TO THE SOUTH. BROAD LOW
PRESSURE WILL SETTLE OVER THE REGION MID TO LATE WEEK...AND A COLD
FRONT COULD APPROACH THEN STALL OVER THE REGION LATE WEEK INTO
NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
THROUGH SUNRISE...WATCHING FOR STRATUS AND FOG DEVELOPMENT
CAREFULLY. LOCALLY DENSE FOG IS A POSSIBILITY AS WIND FIELDS
REMAIN LIGHT...GROUNDS ARE WET AND SKIES ARE CLEAR. RAP AND H3R
BOTH SHOW ISOLATED TO SCATTERED SHOWERS/TSTMS REDEVELOPING ALONG
THE GEORGIA COAST OVER THE NEXT FEW HOURS AS COASTAL WINDS
INCREASE AND LOW-LEVEL CONVERGENCE BUILDS FROM ROUGHLY HILTON HEAD
SOUTH TO THE ALTAMAHA SOUND. WILL CARRY 20-30 PERCENT POPS IN THIS
AREAS TO OVER THIS POSSIBILITY...BUT CONFIDENCE IS NOT VERY HIGH
IN THIS SOLUTION WITH THE 4KM NSSL WRF DEPICTING CONSIDERABLY LESS
COVERAGE THROUGH 8 AM.
TODAY...THE SURFACE TROUGH/REMNANT COLD FRONT IS LOCATED WELL TO
THE SOUTH AND WILL REMAIN QUASI-STATIONARY OVER NORTHERN FLORDIA
TODAY. DRIER AIR WILL ADVECT SLOWLY SOUTH THIS MORNING WITH
DEWPOINTS PROGGED TO DROP INTO THE LOWER-MID 60S ACROSS NORTH
AREAS AND DOWN TO AROUND 70 OR SO ACROSS THE FAR SOUTHERN
PORTIONS OF THE FORECAST AREA. IT WILL REMAIN SEASONABLE WARM WITH
HIGHS IN THE LOWER-MID 90S...BUT IT WILL FEEL CONSIDERABLY LESS
OPPRESSIVE WITH SUCH LOW HUMIDITY IN PLACE--A RARITY FOR SURE AT
THE END OF JULY. SHOULD SEE A SHALLOW CUMULUS FIELD DEVELOP OVER
SOUTHEAST GEORGIA AS WELL AS PARTS OF JASPER AND BEAUFORT COUNTIES
LATER THIS MORNING AS IT WILL TAKE LONGER FOR DEWPOINTS TO LOWER
THERE. THE CUMULUS FIELD SHOULD STEADILY MIX OUT AS THE AFTERNOON
PROGRESSES.
AN ISOLATED SHOWER/TSTM CAN NOT BE COMPLETELY RULED OUT ACROSS
PARTS OF LIBERTY...LONG AND MCINTOSH COUNTIES WHERE LOW-LEVEL
COASTAL SPEED CONVERGENCE INDUCED BY MODEST NORTHEAST WINDS COULD
INTERACT WITH SOME LINGERING INSTABILITY. HOWEVER...FORECAST
SOUNDINGS SHOW THE ATMOSPHERE BECOMING INCREASINGLY CAPPED MID-
LATE AFTERNOON WHICH SHOULD END THE RISK FOR ANY MEANINGFUL
CONVECTION. WILL CARRY SLIGHT CHANCE POPS IN THESE AREAS WITH DRY
CONDITIONS ELSEWHERE.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
TONIGHT...THE BOUNDARY LAYER IS POISED TO DECOUPLE AFTER SUNSET
AS HIGH PRESSURE CENTERED OFF THE MID-ATLANTIC COAST NOSES
SOUTHWEST INTO THE AREA. LIGHT WINDS...LOW DEWPOINTS AND CLEAR
SKIES WILL PROMOTE MODEST RADIATIONAL CONDITIONS SO HAVE UTILIZED
THE LOWER END OF THE GUIDANCE SPECTRUM TO CONSTRUCT THE LOW
TEMPERATURE FORECAST. LOWS WILL RANGE FROM THE UPPER 60S INLAND
TO THE LOWER 70S AT THE COAST WITH MID 70S AT THE BEACHES AND
DOWNTOWN CHARLESTON. A FEW MID 60S WILL LIKELY OCCUR WELL INLAND...
ESPECIALLY IN THE NORMALLY COLDER LOCATIONS. THE 25/00Z GFS COOP
GUIDANCE FOR ALLENDALE IS FORECASTING A LOW OF 63 DEGREES WHICH IS
HIGHLY UNUSUAL FOR LATE JULY. IT APPEARS ALL THREE CLIMATE SITES
WILL LIKELY REMAIN ABOVE THEIR RESPECTIVE RECORD LOWS FOR 26 JULY.
SUNDAY...EXPECT NEAR NORMAL HIGH TEMPERATURES IN THE LOWER TO MID
90S AWAY FROM THE COAST...BUT UNSEASONABLY LOW DEWPOINTS IN THE
LOWER TO MID 60S WILL ALSO BE COMMON. TEMPERATURES WILL REMAIN IN
THE 80S ON THE BEACHES COURTESY OF ONSHORE WINDS. CANNOT COMPLETELY
RULE OUT A COUPLE OF ISOLATED/BRIEF SHOWERS ALONG THE SEA BREEZE
SUNDAY AFTERNOON...BUT RIDGING AT THE SURFACE AND ALOFT SHOULD
PRODUCE SUBSIDENCE/CAPPING...SO ODDS FAVOR MOST/ALL AREAS REMAINING
RAIN-FREE. THUS...HELD POPS BELOW 15 PERCENT WITH NO MENTION OF
RAIN. TRANQUIL CONDITIONS WILL CONTINUE SUNDAY NIGHT WITH NEAR
NORMAL LOWS IN THE LOWER 70S INLAND TO THE MID/UPPER 70S ON THE
BEACHES.
MONDAY...AS THE UPPER RIDGE RETREATS WEST...THE UPPER FLOW WILL TURN
TOWARD THE NORTHWEST...PUSHING A SHORTWAVE AND ASSOCIATED DEEPER
MOISTURE INTO THE REGION. PER 25/00Z GUIDANCE TRENDS...ADDED SLIGHT
CHANCE POPS TO MONDAY AFTERNOON FORECASTS. HOWEVER...INSTABILITY
COULD REMAIN RATHER WEAK...AND THE POTENTIAL FOR THUNDER COULD
REMAIN LIMITED. OTHERWISE...HIGHS IN THE LOWER TO MID 90S INLAND/80S
ON THE BEACHES CAN BE EXPECTED...AND DEWPOINTS WILL CREEP UPWARD
INTO THE UPPER 60S INLAND TO LOWER/MID 70S AT THE COAST.
MONDAY NIGHT AND TUESDAY...NORTHWEST FLOW/SHORTWAVE TROUGHS ALOFT
AND THE ASSOCIATED POOL OF ENHANCED MOISTURE COULD CONTINUE TO
SUPPORT ISOLATED/DIURNAL SHOWERS/THUNDERSTORMS INTO MONDAY EVENING
AND ISOLATED/SCATTERED THUNDERSTORMS TUESDAY AFTERNOON. LOWS IN
THE 70S MONDAY NIGHT WILL BE FOLLOWED ONCE AGAIN BY HIGHS IN THE
LOWER/MID 90S INLAND AND 80S ON THE BEACHES TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
THIS PERIOD BEGINS WITH CONSIDERABLE FORECAST UNCERTAINTY. THE
25/00Z GFS AND NAM SOLUTIONS DEPICT THE POOL OF ENHANCED MOISTURE
WHICH HAD PASSED THROUGH THE REGION MONDAY-TUESDAY BEING SHUNTED TO
THE SOUTH/SOUTHWEST OF THE REGION AS SIGNIFICANTLY DRIER AIR SPREADS
INTO THE REGION FROM THE NORTHEAST...HOLDING DEEPER TROPICAL
MOISTURE WELL SOUTH/SOUTHEAST OF THE REGION. IF THIS SCENARIO
VERIFIES...EXPECT NEAR NORMAL TEMPERATURES AND BELOW NORMAL POPS
WEDNESDAY THROUGH THURSDAY. HOWEVER...THE 25/00Z EUROPEAN DEPICTS AN
EARLY TRANSITION TO BROAD LOW PRESSURE AT THE SURFACE AND ALOFT OVER
THE SOUTHEAST BY MID WEEK...PULLING TROPICAL MOISTURE INTO THE
REGION FROM THE SOUTH/SOUTHEAST AND SUPPORTING A MUCH WETTER REGIME
AND BELOW-NORMAL TEMPERATURES DURING THIS PERIOD. THE LATEST
FORECAST SEEKS THE MIDDLE GROUND BETWEEN THESE SOLUTIONS...FEATURING
NEAR NORMAL TEMPERATURES AND SEASONAL POPS WEDNESDAY THROUGH
THURSDAY. THEN...THE GFS ALSO TRANSITIONS TO A BROAD/DEEP LAYERED
CYCLONIC FLOW REGIME OVER THE SOUTHEAST...AND MODEL AGREEMENT
ACTUALLY IMPROVES REGARDING ABOVE-NORMAL POPS AND BELOW-NORMAL
TEMPERATURES LATE WEEK INTO NEXT WEEKEND. FURTHER...A WEAKENING COLD
FRONT IS PROGGED TO PUSH INTO THIS REGIME AND STALLS...PERHAPS
ENHANCING THE POTENTIAL FOR SHOWERS/THUNDERSTORMS WHICH IN TURN WILL
HOLD DOWN TEMPS.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
WATCHING FOR POSSIBLE LOW STRATUS AND FOG TO DEVELOP AT THE
TERMINALS PRIOR TO SUNRISE AS HIGH CLOUDS SCOUR OUT. BEST CHANCES
FOR IFR CIGS WILL BE AT KSAV WHERE DEWPOINTS WILL REMAIN
ELEVATED...BUT PROBABILITIES AT KCHS ARE NON-ZERO. THERE ARE
INDICATIONS THAT A BRIEF PERIOD OF LIFR CIGS COULD OCCUR AT
KSAV...POSSIBLY BELOW ALTERNATE MINIMUMS. WILL SHOW A TEMPO GROUP
FROM 09/12Z FOR BKN004...BUT HOLD OFF ON SHOWING PREVAILING
CONDITIONS THAT LOW UNTIL TRENDS BECOME ESTABLISHED. AT
KCHS...WILL ONLY SHOW MVFR VSBYS WITH SCT004 TO TREND. MAY VERY
WELL NEED LIFR OR IFR CIGS AT KCHS...BUT A DRYING UPSTREAM AIRMASS
MAY KEEP CONDITIONS FROM BOTTOMING OUT AS IT FILTERS SOUTH.
VFR FOR THE REMAINDER OF THE PERIOD.
EXTENDED AVIATION OUTLOOK...THERE ARE NO CONCERNS.
&&
.MARINE...
TODAY...A MODEST NORTHEAST WIND SURGE WILL WORK DOWN THE COAST
TODAY AS HIGH PRESSURE NOSES IN FROM THE NORTHEAST. SPEEDS LOOK TO
MAX OUT AT 15-20 KT LATER THIS MORNING...THEN SLOWLY DIMINISH
FROM NORTHEAST TO SOUTHWEST DURING THE AFTERNOON. SEAS WILL BUILD
IN THE DEVELOPING NORTHEAST FETCH AND MAXING OUT 2-4 FT NEARSHORE
WATERS AND 4-5 FT OFFSHORE WATERS. BOTH WINDS AND SEAS LOOK TO
REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS ATTM...BUT IT COULD
STILL BE NASTY AT TIMES FOR SMALL CRAFT.
TONIGHT...EAST WINDS THIS EVENING WILL TIP BACK TO THE NORTHEAST
AFTER MIDNIGHT AS THE INLAND/MARINE THERMAL GRADIENT TIGHTENS.
SPEEDS WILL REMAIN AROUND 10 KT AND SEAS WILL AVERAGE 2-3 FT
NEARSHORE WATER AND 3-5 FT OFFSHORE WATERS.
SUNDAY THROUGH WEDNESDAY...SYNOPTIC ONSHORE FLOW WILL PREVAIL
SUNDAY THROUGH WEDNESDAY...ENHANCED BY THE DAILY SEA BREEZE
CIRCULATION...AND WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL
CRAFT ADVISORY LEVELS. FORECAST UNCERTAINTY INCREASES LATE IN THIS
FORECAST PERIOD AS WINDS/SEAS WILL DEPEND ON THE RELATIVE
POSITIONS OF HIGH PRESSURE TO THE NORTH...A STATIONARY FRONT OVER
OR CLOSE TO THE WATERS AND BROAD LOW PRESSURE WHICH COULD DEVELOP
OVER THE REGION.
RIP CURRENTS...INCREASING NORTHEAST WINDS COMBINED WITH A 2 FT
10-12 SECOND GROUND SWELL WILL YIELD A MODERATE RISK FOR RIP
CURRENTS FOR ALL BEACHES TODAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/SPR
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1142 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 1142 PM CDT FRI JUL 24 2015
UPDATED AVIATION SECTION FOR 06Z TAF PACKAGE.
UPDATE ISSUED AT 844 PM CDT FRI JUL 24 2015
UPDATED THE FORECAST TO REMOVE ALL POPS THROUGH THE REMAINDER OF
THE NIGHT. CONVECTION OVER MISSOURI HAS PUSHED WELL WEST OF OUR
AREA...AND THE LATEST HRRR TAKES IT FARTHER TO THE SOUTH AND WEST
THROUGH THE NIGHT. THE NEAREST CONVECTION NORTHWEST OF THE REGION
IS OVER SOUTHERN NEBRASKA...AND ALL INDICATIONS ARE THAT WHAT EVER
IS LEFT OF IT WILL NOT REACH OUR REGION BY 12Z.
THE OTHER ADJUSTMENT WAS TO SHOW A SHARPER DEWPOINT GRADIENT TO
MATCH OBSERVATIONS. WITH WINDS EXPECTED TO BE CALM AND SKIES
EXPECTED TO REMAIN CLEAR THROUGH THE NIGHT...GOOD RADIATIONAL
COOLING SHOULD TAKE TEMPERATURES CLOSE TO THE CURRENT DEWPOINTS.
AS A RESULT...KNOCKED LOW TEMPERATURES DOWN A COUPLE OF DEGREES IN
THE EVANSVILLE TRI STATE REGION.
WITH CONDITIONS FORECAST TO BE CLOSE TO SATURATION BY
DAYBREAK...WILL HAVE TO MONITOR FOR FOG POTENTIAL...ESPECIALLY IN
THE SOUTHWEST HALF OF THE AREA WHERE BETTER LOW-LEVEL MOISTURE IS
PRESENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 319 PM CDT FRI JUL 24 2015
FIRST ITEM IS...WE WILL BE NEAR HEAT ADVISORY CRITERIA THIS
WEEKEND ACROSS THE OZARK FOOTHILL REGION OF SEMO. WILL LET THE
MID SHIFT ADDRESS THIS AS WE ARE BARELY AT CRITERIA. COORD WITH MEG
AND THEY DO NOT HAVE ONE OUT YET TO OUR SOUTH. HI RES MODELS KEEP
CONVECTION WEST OF SEMO REST OF TODAY. WILL KEEP IT DRY THROUGH
MIDNIGHT AND MONITOR. AFTER MIDNIGHT THE MODELS DEVELOP SOME
CONVECTION OVER SEMO (MAINLY LATE). HAVE SLIGHT CHANCE POPS IN TO
ACCOUNT FOR THIS.
WE HAVE HAVE A CONTINUED SLIM CHANCE OF CONVECTION FAR WEST
SATURDAY. QUASI MID LEVEL RIDGE SHOULD PRECLUDE EASTWARD
EXPANSION. HOWEVER BY SATURDAY NIGHT INTO SUNDAY...WE TRANSITION
BACK TO A NW FLOW ON THE EDGE OF H5 RIDGE TO OUR SW. CHANCES OF
CONVECTION INCREASE FROM THE NW AS A RESULT. HEIGHTS START TO RISE
SUNDAY NIGHT AND SHIFT BEST CONVECTIVE CHANCES TO OUR NE.
TEMPS WILL CONTINUE TO BE A BLEND OF PERSISTENCE AND MOS DURING
THE DAY...AND NEAR OR A DEGREE OR TWO ABOVE MOS AT NIGHT.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 319 PM CDT FRI JUL 24 2015
THE PAH FORECAST AREA WILL REMAIN ON THE FRINGES OF A SRN CONUS
MID/UPPER RIDGE FOR THE FIRST HALF OF THE EXTENDED FORECAST PERIOD.
MED RANGE MODELS (DETERMINISTIC AND ENSEMBLES) HAVE SHOWN SOME
VARIABILITY...BUT ARE IN GENERAL AGREEMENT ON THE OVERALL SYNOPTIC
PATTERN. IN THE LATTER HALF OF THE PERIOD...A ROBUST SHRTWV ALOFT IS
PROGGED TO SWEEP THROUGH THE NRN HALF OF THE CONUS...DRAGGING A SFC
BOUNDARY THROUGH OUR REGION. THIS WILL RESULT IN HOT HUMID
CONDITIONS AHEAD OF THE SYSTEM...AND SOMEWHAT COOLER AND DRIER
CONDITIONS BEHIND THE SYSTEM.
A QUASI-STATIONARY FRONTAL BOUNDARY MAY BE IN NRN REACHES OF THE PAH
FORECAST AREA ON MON/MON NIGHT. SUBTLE MID LEVEL SHRTWV ENERGY MAY
ACT ON THIS BOUNDARY AND THE AVAILABLE MOISTURE TO GENERATE SOME
SHOWERS AND TSTMS...BUT ONLY FOR PARTS OF SERN IL/SWRN IND/ERN
PENNYRILE REGION.
TUE/TUE NIGHT LOOKS DRY UNDER THE CAPPING INFLUENCE OF THE SRN
RIDGE...THEN HEIGHT FALLS SHOULD BEGIN TO HAPPEN BY WED...AND THIS
MAY BE ENOUGH TO TAP THE TROP`S MOISTURE AND INSTABILITY FOR THE
DEVELOPMENT OF WIDELY SCATTERED ACTIVITY JUST ABOUT ANYWHERE. AT
THIS TIME...FROPA IS SLATED TO OCCUR WED NIGHT. THE FORCING
ASSOCIATED WITH THIS FEATURE WILL INCREASE THE CHANCES OF PCPN FOR
THE ENTIRE REGION MAINLY EARLY THU. STILL...POPS WILL NOT BE HIGHER
THAN 40 PERCENT DURING THE ENTIRE EXTENDED FORECAST.
WITH DEWPOINTS INITIALLY IN THE LOWER HALF OF THE 70S...EXPECT A
ROUND OF UNCOMFORTABLE AFTERNOON HEAT INDICES THROUGH WED. READINGS
OF 105 (HEAT ADVISORY CRITERIA) MAY BE COMMON IN THE WRN HALF OF THE
REGION MON...AND ACROSS THE ENTIRE REGION BY TUE AND WED.
&&
.AVIATION...
ISSUED AT 1142 PM CDT FRI JUL 24 2015
MVFR FOG POSSIBLE MAINLY AT KPAH/KEVV/KOWB BETWEEN 07Z-13Z. MID-
HIGH CLOUDS EXTENDING FROM THUNDERSTORM COMPLEX OVER MISSOURI WILL
MAINLY AFFECT KCGI/KPAH OVERNIGHT. KCGI CIGS COULD BRIEFLY DIP TO
MVFR THROUGH 12Z. CALM TO LIGHT AND VARIABLE WINDS OVERNIGHT WILL
BECOME SOUTHWEST AROUND 5 KTS AFTER 13Z.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AVIATION...RST
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
330 AM EDT SAT JUL 25 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 330 AM EDT SAT JUL 25 2015
IT WILL FEEL LIKE THE DOG DAYS OF SUMMER AS WE HEAD THROUGH THE REST
OF THE WEEKEND AND INTO THE MIDDLE PART OF THE WORK WEEK. HIGHS WILL
LIKELY TOP OUT IN THE MIDDLE 80S TODAY WITH UPPER 80S IN MANY AREAS
FOR SUNDAY AND MONDAY. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE
NEXT WEEK AS WE WILL LIKELY PUSH TO OR EXCEED 90 DEGREES. A
WEAKENING COLD FRONT IS EXPECTED TO SLIDE THROUGH SOUTHWEST LOWER
MICHIGAN TODAY AND BRING WITH IT SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WIDESPREAD PRECIPITATION IS NOT EXPECTED...IN FACT MANY
AREAS WILL REMAIN DRY. FAIR AND DRY WEATHER IS ON TAP FOR SUNDAY
INTO EARLY NEXT WEEK AS HIGH PRESSURE WILL BE SITUATED OVER THE
AREA.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
CONCERNS IN THE SHORT TERM ARE RELATED TO SHOWER AND STORM CHANCES
TODAY AND THEN TWEAKING HIGH TEMPERATURES THE NEXT COUPLE DAYS AS WE
WILL BE QUITE WARM.
AS FOR CONVECTION TODAY...IT LOOKS LESS AND LESS IMPRESSIVE WITH
EACH MODEL RUN. THE HRRR GUIDANCE IS ONLY SHOWING SCATTERED STORMS
AT BEST. THE LATEST RAP GUIDANCE IS INDICATING MOST UNSTABLE CAPE
VALUES OF 1000-2000 J/KG WHICH IS MORE THAN ENOUGH...BUT OTHER
FACTORS LIMIT THE THREAT. THEY ARE NAMELY...THE MAIN SHORTWAVE IS
WELL NORTH OF THE AREA AND A WIND OFF THE LAKE WILL LIKELY TEMPER
INSTABILITY DURING THE AFTERNOON. MID LEVEL LAPSE RATES ARE NOT
STEEP EITHER...ON THE ORDER OF 5.5 C/KM. THE LLJ AND 850MB MOISTURE
TRANSPORT HAVE TRENDED DOWN AS WELL. BOTTOM LINE...LOOKING FOR
SCATTERED STORMS TO DEVELOP MIDDAY AND WORK SOUTH/EAST OUT OF THE
AREA DURING THE AFTERNOON HOURS. ANY CHANCE OF A STRONG STORM WOULD
BE DURING THE AFTERNOON TOWARDS LAN/BTL/JXN.
OTHERWISE FAIR WEATHER IS EXPECTED WITH HIGH PRESSURE BUILDING IN
BEHIND THE WEAKENING COLD FRONT. AFTER TODAY WITH CLOUDS ASSOCIATED
WITH THE FRONT...SKIES SHOULD BE MAINLY CLEAR. THINKING WE WILL PUSH
INTO THE MID 80S TODAY...CLOUD COVER IS A BIT OF A CONCERN WHICH
COULD TREND THINGS EITHER SIDE OF THOSE NUMBERS. UPPER 80S LOOK
PRETTY SOLID FOR SUNDAY AND MONDAY GIVEN 850MB TEMPS IN THE 17-19C
RANGE.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
OUR MAIN FOCUS OF THE LONG TERM IS THE FRONTAL PASSAGE THAT IS
EXPECTED DURING THE MID-WEEK TIME FRAME...AND THE CHCS OF CONVECTION
THAT WILL ACCOMPANY THE FRONT.
THE BEGINNING OF THE PERIOD IS EXPECTED TO BE HOT AND HUMID WITH
LITTLE CHCS OF RAIN INITIALLY. WE WILL HAVE A FAIRLY DECENT UPPER
RIDGE IN PLACE. THIS UPPER RIDGE WITH HIGH HEIGHTS WILL SUPPORT THE
HOT WEATHER AND WILL CAP THE ATMOSPHERE OFF FROM ANY PCPN FROM
OCCURRING. WE ARE LOOKING AT A GOOD CHANCE OF LOWER 90S ON TUE WITH
H850 TEMPS APPROACHING 20C.
THERE IS A LITTLE UNCERTAINTY WITH THE SPECIFIC TIMING OF THE
SHOWERS/STORMS WITH THE FRONT MID-WEEK. THE CONSENSUS OF THE CHC OF
SHOWERS/STORMS LOOKS TO OCCUR TUE NIGHT INTO WED. SOME MODELS ARE A
LITTLE EARLIER...AND SOME ARE A LITTLE LATER. IT DOES NOT LOOK LIKE
A STRONG FEED OF GULF MOISTURE WILL BE PRESENT. ENOUGH SHOULD BE
AROUND WITH THE STRENGTH OF THE FRONT TO BRING A DECENT CHC OF RAIN.
SEVERE CHCS ARE NOT LOOKING REAL STRONG AT THIS POINT. THERE DOES
LOOK TO BE A GOOD DEAL OF INSTABILITY PRESENT...ESPECIALLY DURING
PEAK HEATING ON WED. DEEP LAYER SHEAR IS LACKING A BIT WITH THE
BETTER WIND FIELDS LAGGING THE FRONT/STORMS A BIT. WE WILL CONTINUE
TO MONITOR THIS POTENTIAL AND THE TRENDS OVER THE NEXT FEW DAYS.
WE WILL SEE A COOL DOWN ALONG WITH DRIER CONDITIONS FOR THE THU AND
FRI TIME FRAME. WE WILL SEE A TROUGH OVER THE AREA EVENTUALLY GIVING
WAY TO A SFC RIDGE. NW FLOW ALOFT AND IN THE LOWER LEVELS WILL COOL
US OFF A BIT. IT DOES NOT LOOK TOO COLD AT THIS TIME WITH H850 TEMPS
DROPPING INTO THE LOWER TEENS C.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 146 AM EDT SAT JUL 25 2015
THE BEGINNING AND END OF THE FCST PERIOD LOOKS QUIET...WITH A
SHORT PERIOD OF A FEW SHOWERS/STORMS ALONG WITH SOME MVFR POSSIBLE
FOR A FEW HOURS IN THE MIDDLE OF THE PERIOD.
CONDITIONS ARE STARTING OUT VFR...AND WILL TREND TOWARD POSSIBLE
MVFR JUST AFTER DAYBREAK AT KMKG AS THE FRONT AND A FEW SHOWERS
WILL ARRIVE. THIS BAND OF POSSIBLE SHOWERS AND LOWER CONDITIONS WILL
PUSH SE...AND COULD BECOME A FEW STORMS SOUTH AND EAST OF KGRR
THIS AFTERNOON. THE MODELS INDICATE THAT SRN AREAS WILL SEE LESS
OF A CHC OF MVFR CIGS.
WE EXPECT THE PCPN TO MOVE OUT BY 22Z AT ALL TERMINALS WITH KJXN
SEEING IT LAST THE LONGEST. CLOUDS WILL THEN CLEAR OUT SHORTLY
AND WINDS WILL SHIFT FROM SW TO NW AS THE FRONT MOVES THROUGH.
&&
.MARINE...
ISSUED AT 330 AM EDT SAT JUL 25 2015
WAVES OF 1 TO 3 FEET ARE EXPECTED THIS MORNING FROM GRAND HAVEN
NORTHWARD IN A ZONE WHERE SOUTHWEST WINDS OF 10 TO 20 KNOTS WILL
BUILD WAVE HEIGHTS. WINDS LOOK A BIT DOWN FROM WHAT WE WERE SEEING
IN THE MODELS THE LAST COUPLE NIGHTS...SO THE MORE WIDESPREAD 2 TO 4
FOOT WAVES LOOK LESS LIKELY.
AFTER THIS MORNING...QUIET WEATHER OUT ON THE BIG LAKE THE REST OF
THE WEEKEND WITH HIGH PRESSURE IN PLACE. WAVES OF 2 FEET OR LESS AND
WINDS LESS THAN 15 KNOTS SHOULD BE COMMON PLACE.
&&
.HYDROLOGY...
ISSUED AT 1156 AM EDT FRI JUL 24 2015
RIVER LEVELS ARE FALLING AND ARE WELL BELOW BANKFULL. WITH UNDER
AN INCH OF PRECIPITATION EXPECTED THROUGH THE WEEK... THESE
CONDITIONS SHOULD CONTINUE. LOCALLY HEAVY RAINFALL COULD LEAD TO
PONDING OF WATER... MAINLY SATURDAY OR WEDNESDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...63
MARINE...DUKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
320 AM EDT SAT JUL 25 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 419 PM EDT FRI JUL 24 2015
WV IMAGERY RAP ANALYSIS INDICATED ZONAL FLOW FROM THE PAC NW TO THE
GREAT LAKES ATOP A RIDGE OVER THE SRN AND CNTRL PLAINS. THE INITIAL
SHORTWAVE OR REMNANTS OF THE MCV FROM EARLIER TODAY THAT BROUGHT AN
AREA OF CLOUDS AND VERY LIGHT SHOWERS THROUGH UPPER MI HAS LIMITED
SFC HEATING AND KEPT MLCAPE VALUES AOB 500 J/KG. CLEARING WITH
SUBSIDENCE IN THE WAKE OF THIS FEATURE HAS ALLOWED TEMPS TO CLIMB
INTO THE LOWER 80S OVER THE WEST WITH MLCAPE VALUES INTO THE 500-
1000 J/KG RANGE OVER THE FAR WEST. A SHRTWV OVER NRN MN ALONG WITH A
COLD FRONT INTO NE MN SUPPORTED SCT SHRA WITH MORE EXTENSIVE CLOUD
COVER.
EXPECT THAT THERE STILL WILL BE ENOUGH HEATING LATE THIS AFTERNOON
OVER MUCH OF WRN UPPER MI TO BOOST MLCAPE VALUES TO AROUND 1K J/KG.
WITH THE COLD FRONT AND SHRTWV EDGING INTO UPPER MI DURING PEAK
HEATING...EXPECT SCT TSRA TO DEVELOP BTWN 21Z-00Z. 0-6KM SHEAR
VALUES IN THE 30-40 KNOT RANGE WOULD BE FAVORABLE FOR STORM
ORGANIZATION WITH THE POTENTIAL FOR ISOLD SEVERE STORMS. HOWEVER...IF
THE THICKER CLOUD COVER SPREADS BACK INTO THE AREA BEFORE THE FRONT
AND STRONGER FORCING WITH THE SHRTWV ARRIVES...TSRA COVERAGE AND
STRENGTH WILL BE SUPPRESSED. ANY REMAINING SHRA/TSRA SHOULD EXIT THE
CWA AFTER 06Z WITH CLEARING MOVING IN OVERNIGHT.
SATURDAY...HIGH PRESSURE WILL BUILD INTO THE AREA WITH MOSTLY SUNNY
SKIES EXPECTED. SUNSHINE AND MIXING WITH 850 MB TEMPS AROUND 16C
SUPPORT MAX READINGS IN THE LOW TO MID 80S INLAND AND FOR LOCATIONS
FAVORED BY NW DOWNSLOPE FLOW.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 320 AM EDT SAT JUL 25 2015
SUNDAY THROUGH MONDAY NIGHT...HIGH PRESSURE ALOFT AND AT THE SURFACE
WILL PERSIST FOR THE BEGINNING OF THE EXTENDED FCST PD (SUNDAY
THROUGH MONDAY NIGHT)...KEEPING CONDITIONS GENERALLY DRY. A FEW OF
THE MODELS GENERATE UP TO 500 J/KG OF MLCAPE SUN AFTERNOON MAINLY
OVER INLAND AREAS OF THE WEST HALF BUT FCST SNDGS LOOK TOO DRY TO
SUPPORT SHRA SO WL CONTINUE TO KEEP DRY FCST. WITH STRENGTHENING
SOUTHERLY FLOW ON THE BACKSIDE OF THE SURFACE RIDGE INTO THE EARLY
PART OF THE WEEK...TEMPERATURES WILL ALSO REMAIN ABOVE NORMAL ACROSS
UPPER MI WITH 8H TEMPS OF 18-20C ACROSS THE AREA.
TUESDAY INTO WEDNESDAY...MODELS SUGGEST THE WARMEST DAY OF THE WEEK
COULD BE ON TUESDAY WHEN 8H TEMPS CLIMB TO 20-22C. HOW WARM THE HIGH
TEMPS GET WILL DEPEND ON THE AMOUNT OF CLOUD COVER SPREADING IN
AHEAD OF THE APPROACHING FRONTAL SYSTEM FROM THE PLAINS. IF WE GET
ENOUGH SUNSHINE...IT/S CERTAINLY POSSIBLE A FEW LOCATIONS OVER THE
WEST HALF OF UPPER MI COULD REACH THE LOW 90S ON TUESDAY. GFS IS
MOST AGGRESSIVE OF MODELS KICKING OFF WAA SHRA AS EARLY AS SUNDAY
NIGHT INTO TUESDAY. CONSENSUS OF MODELS DEPICT DRIER CONDITIONS
UNDER RIDGING INTO TUESDAY SUGGESTING GFS SOLN IS AN OUTLIER. MODEL
CONSENSUS INDICATES BEST CHANCE OF SHRA/TSRA NEXT WEEK WILL BE TUE
NIGHT INTO WEDNESDAY WHEN A STRONG SHORTWAVE MOVING ACROSS THE
NORTHERN PLAINS PROPELS A COLD FRONT ACROSS UPPER MI. LAYER PWATS
NEARLY TWO INCHES AHEAD OF THE FRONT ALONG WITH MLCAPES OF 800-1500
J/KG WOULD INDICATE T-STORMS WITH THE POTENTIAL FOR LOCALLY HEAVY
RAIN TUE NIGHT INTO EARLY WED. FRONT EXITING EAST OF THE REGION WILL
ALLOW LINGERING CONVECTION OVER ERN CWA TO END BY WED AFTERNOON.
LATE WED AFTERNOON INTO THURSDAY NIGHT...MODELS DEPICT SFC HIGH PRES
RIDGE BUILDING IN BEHIND THE FRONTAL BOUNDARY WED NIGHT INTO
THURSDAY WHICH SHOULD PROVIDE FOR DRIER AND COOLER CONDITIONS DURING
THIS PERIOD.
FRIDAY...ANOTHER SHORTWAVE DIVING ACROSS SCNTRL CANADA WILL PUSH
ANOTHER FRONTAL BOUNDARY ACROSS THE AREA FRIDAY AFTERNOON AND
EVENING. MOISTURE WILL DEFINITELY BE MORE LIMITED WITH THIS SYSTEM
AS MODELS SHOW ABSENCE OF GULF MOISTURE CONNECTION. 8H THERMAL RIDGE
OF 18-20C AHEAD OF THE FRONT COULD ALLOW FOR ANOTHER FAIRLY WARM DAY
PROVIDED CLOUDS DON`T MOVE IN TOO EARLY AHEAD OF THE FRONT. MLCAPES
OF GENERALLY 500-1000 J/KG AND NEGATIVE SHOWALTER INDICES WILL
WARRANT THUNDER MENTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 158 AM EDT SAT JUL 25 2015
COLD FRONT MOVING THROUGH EARLY THIS MORNING WILL CONTINUE TO
TRIGGER SCT SHRA/TSRA AT KSAW. OTHERWISE...POTENTIAL FOR SHRA/TSRA
HAS ENDED AT KIWD AND KCMX. MAY SEE A PERIOD OF MVFR STRATUS REST OF
THE NIGHT IN WAKE OF THE COLD FRONT AT ALL THE TAF SITES BUT DRY AIR
SWEEPING IN THIS MORNING WILL QUICKLY SCOUR OUT ANY LOW CLOUDS AND
RETURN CONDITIONS TO VFR. ONLY OTHER ISSUE FOR REST OF THE DAY WILL
BE GUSTY WEST WINDS POSSIBLY OVER 20 KTS AT KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 PM EDT FRI JUL 24 2015
AS A COLD FRONT MOVES EAST ACROSS THE LAKE LATE TONIGHT...WINDS WILL
SHIFT WRLY 15-20KTS FOR SATURDAY. HIGH PRESSURE WILL BUILD BACK INTO
THE WESTERN GREAT LAKES SAT NIGHT AND PERSIST INTO TUE KEEPING WINDS
GENERALLY BELOW 15KTS. ANY FOG OVER LAKE IS EXPECTED TO DIMINISH
SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...JLA
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
158 AM EDT SAT JUL 25 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 419 PM EDT FRI JUL 24 2015
WV IMAGERY RAP ANALYSIS INDICATED ZONAL FLOW FROM THE PAC NW TO THE
GREAT LAKES ATOP A RIDGE OVER THE SRN AND CNTRL PLAINS. THE INITIAL
SHORTWAVE OR REMNANTS OF THE MCV FROM EARLIER TODAY THAT BROUGHT AN
AREA OF CLOUDS AND VERY LIGHT SHOWERS THROUGH UPPER MI HAS LIMITED
SFC HEATING AND KEPT MLCAPE VALUES AOB 500 J/KG. CLEARING WITH
SUBSIDENCE IN THE WAKE OF THIS FEATURE HAS ALLOWED TEMPS TO CLIMB
INTO THE LOWER 80S OVER THE WEST WITH MLCAPE VALUES INTO THE 500-
1000 J/KG RANGE OVER THE FAR WEST. A SHRTWV OVER NRN MN ALONG WITH A
COLD FRONT INTO NE MN SUPPORTED SCT SHRA WITH MORE EXTENSIVE CLOUD
COVER.
EXPECT THAT THERE STILL WILL BE ENOUGH HEATING LATE THIS AFTERNOON
OVER MUCH OF WRN UPPER MI TO BOOST MLCAPE VALUES TO AROUND 1K J/KG.
WITH THE COLD FRONT AND SHRTWV EDGING INTO UPPER MI DURING PEAK
HEATING...EXPECT SCT TSRA TO DEVELOP BTWN 21Z-00Z. 0-6KM SHEAR
VALUES IN THE 30-40 KNOT RANGE WOULD BE FAVORABLE FOR STORM
ORGANIZATION WITH THE POTENTIAL FOR ISOLD SEVERE STORMS. HOWEVER...IF
THE THICKER CLOUD COVER SPREADS BACK INTO THE AREA BEFORE THE FRONT
AND STRONGER FORCING WITH THE SHRTWV ARRIVES...TSRA COVERAGE AND
STRENGTH WILL BE SUPPRESSED. ANY REMAINING SHRA/TSRA SHOULD EXIT THE
CWA AFTER 06Z WITH CLEARING MOVING IN OVERNIGHT.
SATURDAY...HIGH PRESSURE WILL BUILD INTO THE AREA WITH MOSTLY SUNNY
SKIES EXPECTED. SUNSHINE AND MIXING WITH 850 MB TEMPS AROUND 16C
SUPPORT MAX READINGS IN THE LOW TO MID 80S INLAND AND FOR LOCATIONS
FAVORED BY NW DOWNSLOPE FLOW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 321 PM EDT FRI JUL 24 2015
NAM SHOWS A SHORTWAVE TOPPING A 500 MB RIDGE OVER THE SOUTHERN U.S.
WITH A TROUGH IN THE WESTERN U.S. AND A SHORTWAVE IN THE DAKOTAS 00Z
SUN. THIS SHORTWAVE MOVES EAST ON SUN AND HAS A SHORTWAVE RIDGE
MOVING IN FOR MON. WILL HAVE IT DRY INTO THE FORECAST INTO MONDAY
BEFORE LAKE BREEZE CONVERGENCE COULD KICK SOMETHING OFF MONDAY
AFTERNOON OVER THE WEST AND CENTRAL. OVERALL...DID NOT MAKE TOO MANY
CHANGES TO THE GOING FORECAST.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB TROUGH OVER THE
ROCKIES 12Z TUE WITH A RIDGE ACROSS THE EASTERN HALF OF THE U.S. THE
TROUGH MOVES INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES ON WED
WITH A SFC COLD FRONT MOVING THROUGH THE AREA. THE UPPER TROUGH AXIS
IS OVER THE UPPER GREAT LAKES 12Z THU WITH UPPER TROUGHING REMAINING
INTO FRI. THIS WILL BRING A COOLING TREND IN THE TEMPERATURES
STARTING OUT ABOVE NORMAL ON TUE COOLING TO BELOW NORMAL ON THU AND
FRI. WITH THE TROUGHING REMAINING OVER THE AREA...HARD TO RULE OUT
PCPN AND HAVE CHANCE POPS IN THROUGH WED AND THEN SLIGHT CHANCE POPS
ON THU AND FRI WITH INSTABILITY SHOWERS AROUND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 158 AM EDT SAT JUL 25 2015
COLD FRONT MOVING THROUGH EARLY THIS MORNING WILL CONTINUE TO
TRIGGER SCT SHRA/TSRA AT KSAW. OTHERWISE...POTENTIAL FOR SHRA/TSRA
HAS ENDED AT KIWD AND KCMX. MAY SEE A PERIOD OF MVFR STRATUS REST OF
THE NIGHT IN WAKE OF THE COLD FRONT AT ALL THE TAF SITES BUT DRY AIR
SWEEPING IN THIS MORNING WILL QUICKLY SCOUR OUT ANY LOW CLOUDS AND
RETURN CONDITIONS TO VFR. ONLY OTHER ISSUE FOR REST OF THE DAY WILL
BE GUSTY WEST WINDS POSSIBLY OVER 20 KTS AT KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 419 PM EDT FRI JUL 24 2015
AS A COLD FRONT MOVES EAST ACROSS THE LAKE LATE TONIGHT...WINDS WILL
SHIFT WRLY 15-20KTS FOR SATURDAY. HIGH PRESSURE WILL BUILD BACK INTO
THE WESTERN GREAT LAKES SAT NIGHT AND PERSIST INTO TUE KEEPING WINDS
GENERALLY BELOW 15KTS. ANY FOG OVER LAKE IS EXPECTED TO DIMINISH
SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...JLA
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
146 AM EDT SAT JUL 25 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 PM EDT FRI JUL 24 2015
AN APPROACHING WEAKENING COLD FRONT WILL CAUSE SCATTERED SHOWERS
AND THUNDERSTORMS TO DEVELOP VERY LATE TONIGHT THROUGH SATURDAY.
WIDESPREAD RAIN IS NOT ANTICIPATED AND MOST OF THIS TIME PERIOD
WILL BE DRY AND VERY WARM. HOT AND INCREASINGLY HUMID WEATHER WILL
DEVELOP SUNDAY THROUGH THE MIDDLE OF NEXT WEEK WITH INCREASING
POTENTIAL FOR SOME THUNDERSTORMS TOWARD THE MIDDLE OF NEXT WEEK.
&&
.UPDATE...
ISSUED AT 1029 PM EDT FRI JUL 24 2015
UPSTREAM TRENDS SUGGEST IT MAY TAKE UNTIL AFTER 5 OR 6 AM FOR
ANY SHOWERS TO GET IN HERE... AND THE THUNDER RISK LOOKS RATHER
LIMITED UNTIL AFTER 11 AM SATURDAY BASED ON LATEST RAP MU CAPE
PROGS. HAVE ADJUSTED POP/WX/SKY GRIDS TO ACCOUNT FOR LATEST
TRENDS AND SHORT RANGE GUIDANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 330 PM EDT FRI JUL 24 2015
PRIMARY SHORT TERM FCST CONCERNS INVOLVE ASSESSMENT OF CONVECTIVE
POTENTIAL VERY LATE TONIGHT THROUGH SATURDAY AFTERNOON.
A WEAKENING COLD FRONT WILL CAUSE SCATTERED SHOWERS AND A FEW
THUNDERSTORMS TO DEVELOP NEAR TO NW OF A LINE FROM KGRR TO KMOP
BETWEEN 06Z AND 12Z SATURDAY AS SUGGESTED BY 12Z NSSL WRF
GUIDANCE. THE STORMS WILL DEVELOP IN AN AXIS OF INCREASING
ELEVATED INSTABILITY AND WITH LOW LEVEL MOISTURE POOLING ALONG AND
AHEAD OF THE FRONT.
SEVERE WX IS NOT ANTICIPATED LATE TONIGHT DUE TO LACK OF DEEP LAYER
SHEAR... WEAK INSTABILITY AND WEAK FORCING FROM THE FRONT. SCATTERED
SHOWERS AND STORMS WILL REDEVELOP ALONG AND JUST AHEAD OF THE FRONT
SATURDAY AS INSTABILITY INCREASES WITH DAYTIME HEATING.
CANNOT ENTIRELY RULE OUT A FEW STRONG TO ISOLATED MARGINALLY SEVERE
STORMS MAINLY OVER OUR SE FCST AREA SATURDAY NEAR TO SE OF KGRR.
OVERALL THOUGH LACK OF STRONGER FORCING... RELATIVELY WEAK
INSTABILITY AND FAIRLY WEAK DEEP LAYER SHEAR ARE ALL MITIGATING
FACTORS. INSTABILITY WILL ALSO LIKELY BE LIMITED SOMEWHAT BY MORNING
CLOUDS AND SCATTERED SHOWERS AND STORMS.
FAIR WX WILL RETURN SATURDAY NIGHT THROUGH SUNDAY AS ANOTHER HIGH
PRESSURE RIDGE BUILDS IN. THERE IS JUST A SMALL CHANCE OF SHOWER
OR THUNDERSTORM LATE SUNDAY NIGHT OVER OUR SW FCST AREA BUT A
CONSENSUS OF SHORTER TO MEDIUM RANGE GUIDANCE SUGGESTS THAT MOST
IF NOT ALL PCPN SUNDAY NIGHT WILL STAY SW TO SOUTH OF OUR FCST AREA.
FOR THE REST OF THIS AFTERNOON AND EVENING DRY AND FAIR WX WILL
CONTINUE FOR THE VAST MAJORITY OF OUR AREA. HOWEVER AN ISOLATED
RAIN SHOWER OR TWO MAY DEVELOP FROM MID TO LATE AFTN THROUGH
EARLY EVE OVER OUR FAR EASTERN FCST AREA COINCIDENT WITH MAX
INSTABILITY FROM DAYTIME HEATING.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 PM EDT FRI JUL 24 2015
MODELS STILL ADVERTISING A STRONGER COLD FRONTAL PASSAGE FOR THE
MIDDLE OF NEXT WEEK. BASED ON THE STRENGTH OF THE DEEP LAYER SHEAR
AND INSTABILITY THAT WILL BE PRESENT WHEN THE FRONT COMES
THROUGH...AND ELEVATED RISK FOR SEVERE WEATHER EXISTS. BETTER THAN
40 KNOTS OF SHEAR ARE SHOWN. WILL CONTINUE TO HIGHLIGHT THIS PERIOD
FOR STORMS...MAINLY TUE NIGHT INTO WED NIGHT.
CONTINUES TO LOOK WELL ABOVE NORMAL FOR TEMPERATURES GOING INTO WED.
850 MB TEMPS CLIMB INTO THE UPPER TEENS TO LOW 20S SUPPORT AT LEAST
MID 80S FOR HIGHS. STRONG COLD AIR ADVECTION BEHIND THE FRONT
SUGGESTS A COOLER THAN NORMAL END OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 146 AM EDT SAT JUL 25 2015
THE BEGINNING AND END OF THE FCST PERIOD LOOKS QUIET...WITH A
SHORT PERIOD OF A FEW SHOWERS/STORMS ALONG WITH SOME MVFR POSSIBLE
FOR A FEW HOURS IN THE MIDDLE OF THE PERIOD.
CONDITIONS ARE STARTING OUT VFR...AND WILL TREND TOWARD POSSIBLE
MVFR JUST AFTER DAYBREAK AT KMKG AS THE FRONT AND A FEW SHOWERS
WILL ARRIVE. THIS BAND OF POSSIBLE SHOWERS AND LOWER CONDITIONS WILL
PUSH SE...AND COULD BECOME A FEW STORMS SOUTH AND EAST OF KGRR
THIS AFTERNOON. THE MODELS INDICATE THAT SRN AREAS WILL SEE LESS
OF A CHC OF MVFR CIGS.
WE EXPECT THE PCPN TO MOVE OUT BY 22Z AT ALL TERMINALS WITH KJXN
SEEING IT LAST THE LONGEST. CLOUDS WILL THEN CLEAR OUT SHORTLY
AND WINDS WILL SHIFT FROM SW TO NW AS THE FRONT MOVES THROUGH.
&&
.MARINE...
ISSUED AT 330 PM EDT FRI JUL 24 2015
WINDS AND WAVE HEIGHTS WILL BRIEFLY INCREASE LATE TONIGHT WITH
WAVE HEIGHTS POTENTIALLY REACHING 2 TO 4 FEET. HOWEVER CONDITIONS
SHOULD REMAIN BELOW SMALL CRAFT/BEACH HAZARDS CRITERIA. WAVE
HEIGHTS AND WIND SPEEDS THROUGH THE WEEKEND WILL BE LIGHT WITH
WAVE HEIGHTS MAINLY AOB 2 FT.
&&
.HYDROLOGY...
ISSUED AT 1156 AM EDT FRI JUL 24 2015
RIVER LEVELS ARE FALLING AND ARE WELL BELOW BANKFULL. WITH UNDER
AN INCH OF PRECIPITATION EXPECTED THROUGH THE WEEK... THESE
CONDITIONS SHOULD CONTINUE. LOCALLY HEAVY RAINFALL COULD LEAD TO
PONDING OF WATER... MAINLY SATURDAY OR WEDNESDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...MJS
AVIATION...NJJ
HYDROLOGY...63
MARINE...LAURENS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1145 PM CDT FRI JUL 24 2015
.UPDATE:
ISSUED AT 934 PM CDT FRI JUL 24 2015
WEATHER LOOKS PRETTY TRANQUIL FOR THE REMAINDER OF THE EVENING AND
INTO THE FIRST PART OF THE OVERNIGHT PERIOD. THE CLUSTER OF STORMS
WHICH REGENERATED OVER CENTRAL MO EARLY THIS EVENING HAS REMAINED
WELL TO THE WEST, TRACKING SOUTH/SOUTHWEST ALONG THE INSTABILITY
GRADIENT AND LARGELY STEERED BY NORTHERLY CLOUD LAYER FLOW. THE THREAT
OF ADDITIONAL STORMS OVERNIGHT SHOULD BE PRIMARLY AFTER 200-300
AM. THE COMBINATION OF SUBTLE WEAK MID LEVEL DISTURBANCES TRACKING
ALONG THE PERIPHERY OF THE HIGH ALOFT ALONG WITH WEAK LOW-LEVEL
WAA AND MOISTURE CONVERGENCE, SUPPORT A THREAT OF POTENTIALLY
MAINTAINING A FEW OF THE STORMS ACROSS SOUTHEAST IA/NW MO, BUT
MORE LIKELY NEW STORM DEVELOPMENT ACROSS NORTHEAST MO INTO CENTRAL
MO.
GLASS
&&
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 356 PM CDT FRI JUL 24 2015
MCS WILL CONTINUE TO WORK SOUTHWARD ALONG THE CAPE GRADIENT DURING
THE NEXT FEW HOURS. THIS IS ALSO IN THE SAME DIRECTION AS THE
FORWARD PROPAGATING CORFIDI VECTORS. THERE REMAINS THE POTENTIAL
FOR SOME SEVERE WIND GUSTS WITH THIS SYSTEM AS THE RAP FORECAST
SOUNDINGS AHEAD OF IT AT KCOU ARE SHOWING INVERTED-V PROFILES. THE
LATEST OBJECTIVE ANALYSIS WHICH SHOWS MLCAPES BETWEEN 3000-4000 J/KG
AND 0-6KM SHEAR NEAR 40KTS. HAVE INCREASE POPS EARLY THIS EVENING
OVER THE EASTERN OZARKS AS THIS SYSTEM MOVES SOUTHWARD ACROSS
EASTERN MISSOURI. HAVE ALSO KEPT CHANCES OVER NORTHEAST AND CENTRAL
MISSOURI INTO WEST CENTRAL ILLINOIS LATE THIS EVENING INTO THE
OVERNIGHT HOURS AS BOTH THE NAM AND GFS ARE SHOWING A SHORTWAVE
TROUGH MOVING EAST SOUTHEAST INTO THE AREA WHICH SHOULD PROVIDE SOME
ASCENT, AND THE RAP IS SHOWING AND INCREASE IN LOW LEVEL MOISTURE
CONVERGENCE OVER THE NORTHERN HALF OF THE CWA. GOING TEMPERATURES
LOOK GOOD FOR LOWS.
BRITT
.LONG TERM: (SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 356 PM CDT FRI JUL 24 2015
THUNDERSTORM TRENDS REMAIN THE KEY QUESTION FOR THE WEEKEND. HAVE
BASICALLY ONLY TWEAKED THE MIDNIGHT SHIFT`S POPS FOR THE WEEKEND.
THIS BREAKS DOWN TO 30-50% CHANCES FOR THE ENTIRE AREA SATURDAY
THROUGH SUNDAY. HIGHER DEWPOINT TEMPERATURES OVER WESTERN AND
CENTRAL MISSOURI SHOULD OVERSPREAD MUCH OF THE AREA PUSHING CAPE
VALUES OVER 3000 J/KG. LINGERING BOUNDARY IN THE VICINITY OF THE
MISSISSIPPI RIVER SHOULD PROVIDE ENOUGH FOCUS FOR AFTERNOON
CONVECTION TO FIRE THOUGH COVERAGE IS UNCERTAIN DUE TO A DECENT CAP.
NOT OVERLY IMPRESSED WITH THE DEEP LAYER SHEAR, BUT WITH THE HIGH
INSTABILITY THERE IS CERTAINLY ENOUGH TO BE CONCERNED WITH MULTI-
CELL CLUSTERS CAPABLE OF PRODUCING STRONG WINDS.
TEMPERATURES ON SATURDAY ARE UNCERTAIN DUE TO THE CHANCES FOR
CONVECTION. HOWEVER, IT DOES APPEAR THAT WE`LL GET WARM ENOUGH TO
REACH HEAT ADVISORY CRITERIA OVER PARTS OF CENTRAL AND SOUTHEAST
MISSOURI WHERE THUNDERSTORM COVERAGE LOOKS TO BE MORE WIDELY
SCATTERED TO ISOLATED. WILL GO AHEAD AND ISSUE AN ADVISORY FOR
THESE AREAS FOR SATURDAY FOR HEAT INDEX VALUES AROUND 105. ADVISORY
MAY NEED TO BE EXPANDED IF STORMS DO NOT DEVELOP AS EXPECTED...OR
POSSIBLY DROPPED IF THE THUNDERSTORM COVERAGE IS GREATER THAN
EXPECTED.
ANOTHER SHORTWAVE IS FORECAST TO MOVE OVERHEAD SATURDAY NIGHT
ASSOCIATED WITH A MODEST LOW LEVEL JET WILL CONTINUE THE THREAT FOR
STORMS OVER MUCH OF THE AREA SUNDAY LOOKS TO BE A REPEAT OF OF
SATURDAY WITH THE SYNOPTIC BOUNDARY CONTINUING TO BE REINFORCED BY
THUNDERSTORMS. THUNDERSTORM CHANCES SHOULD BE WANING QUICKLY THOUGH
FOR SUNDAY NIGHT INTO THE BEGINNING OF NEXT WEEK AS A STRONG UPPER
LEVEL RIDGE BUILDS ACROSS THE AREA. THINK THE VAST MAJORITY OF THE
AREA SHOULD BE DRY BY LATE SUNDAY NIGHT AND MONDAY WITH ONLY SLIGHT
CHANCE POPS MONDAY AND TUESDAY. MEDIUM RANGE MODELS HAVE A WEAK COLD
FRONT MOVING THROUGH THE AREA WEDNESDAY NIGHT INTO THURSDAY WITH
ANOTHER CHANCE FOR STORMS.
CARNEY
&&
.AVIATION: (FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1130 PM CDT FRI JUL 24 2015
NOT MUCH CHANGE FROM THE PREV TAFS. HAVE ADDED MENTION OF TS AT
UIN NEAR SUNRISE AS ONGOING ACTIVITY SHUD BE NEAR THE REGION THEN.
UNCERTAINTY REMAINS WHAT COVERAGE WILL BE WHEN IT ARRIVES AND HAVE
THEREFORE KEPT ONLY VC MENTION FOR NOW. STORMS OVER NW MO IS
CURRENTLY TIMED INTO COU AREA AROUND 09Z AND HAVE ADDED TO THE
TAF. A LOT OF UNCERTAINTY REMAINS IF THESE STORMS WILL CONTINUE
FURTHER E THAN COU...OR IF THEY WILL FOR SURE EVEN MAKE IT THAT
FAR E. OTHERWISE...HAVE ADDED VC MENTION DURING THE AFTN HRS AT
SUS/CPS.
SPECIFICS FOR KSTL: HAVE KEPT TAF DRY THRU MORNING HRS.
HOWEVER...ONGOING STORMS OVER NW MO MAY CONTINUE AS FAR E AS
TERMINAL. OTHERWISE...HAVE ADDED VC MENTION DURING THE AFTERNOON
HRS AS BEST TIMES OF IMPACTING THE TERMINAL.
TILLY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY FROM NOON TO 7 PM CDT SATURDAY FOR BOONE MO-
CALLAWAY MO-COLE MO-CRAWFORD MO-FRANKLIN MO-GASCONADE MO-
IRON MO-MONITEAU MO-MONTGOMERY MO-OSAGE MO-REYNOLDS MO-
WARREN MO-WASHINGTON MO.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
251 AM CDT SAT JUL 25 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 208 AM CDT SAT JUL 25 2015
MAIN CONCERN WILL REVOLVE AROUND HOW WELL MODELS HANDLE CONVECTIVE
EVENTS TODAY AND TONIGHT...THEN TEMPERATURES AS UPPER RIDGE
REBUILDS ACROSS THE PLAINS REGION.
LAST EVENINGS CONVECTIVE COMPLEX ABOUT TO PUSH EAST OF THE CWA AT
08Z WITH STRONGEST CLUSTER OVER SOUTHWEST IOWA AND EXTREME
SOUTHEAST NEBRASKA. 06Z RAP DOWNPLAYS CONVECTION FOR THE MORNING
PERIOD COMPARED TO NAM OR GFS WITH LATTER MODELS FOCUSING ON A
COMPLEX COMING OUT OF SOUTH DAKOTA. PLAN TO FOLLOW THE RAP TREND
THIS MORNING UNLESS NEW DEVELOPMENT INTENSIFIES TO THE WEST...WITH
POPS INCREASING DURING THE AFTERNOON AND TONIGHT. SOME SMALL
CHANCE OF MAINLY OVERNIGHT CONVECTION SUNDAY NIGHT INTO EARLY
MONDAY BUT WARM MID LEVELS AND STRONGER FLOW TO THE NORTHWEST
AHEAD OF A DEEP UPPER TROUGH WILL HINDER DEVELOPMENT.
CLOUDS AND PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
HOLD TEMPERATURES DOWN TODAY. WARMER TEMPS RETURN FOR SUNDAY AND
MONDAY ALTHOUGH WITH NO SURFACE FRONT IN THE AREA WILL BE LIMITED
TO THE LOWER 90S FOR MOST AREAS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 208 AM CDT SAT JUL 25 2015
NEXT COLD FRONT EXPECTED TO COME INTO THE AREA TUESDAY INTO
TUESDAY NIGHT WITH A BETTER CHANCE OF STORMS FOR THE AREA
ASSOCIATED WITH THE FRONT. SOUTH PARTS OF THE AREA COULD SEE
HOT TEMPERATURES AGAIN IN ADVANCE OF THE FRONT ON TUESDAY.
SOME LINGERING PRECIP IN THE FAR SOUTH ON WEDNESDAY BEFORE FRONT
PUSHES FURTHER SOUTH. DEEP UPPER LOW MOVING ACROSS CANADA WILL DIG
A TROUGH IN THE EAST AND RETROGRADE UPPER HIGH CENTER BACK TO THE
SOUTHWEST PART OF THE NATION WEDNESDAY NIGHT THROUGH FRIDAY WITH
SEASONAL TEMPERATURES EXPECTED DURING THAT TIME.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1138 PM CDT FRI JUL 24 2015
LINE OF POTENTIALLY SEVERE STORMS IS JUST WEST OF KLNK...SHOULD
IMPACT THAT LOCATION 05-06Z. STORMS SHOULD REACH KOMA BY 06-07Z.
WILL FORECAST A 2 HOUR WINDOW OF STORMS...THEN LINGERING SHOWERS
THAN COULD LAST UNTIL 10-12Z. STILL THINKING THAT KOFK MAY BE TOO
FAR NORTH TO GET ANY PRECIP WITH THIS FIRST ROUND. SHOULD SEE NEW
THUNDERSTORM DEVELOPMENT LATER IN THE TAF PERIOD...18-23Z AT
KOFK...AND 20-03Z AT KLNK/KOMA.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
402 AM CDT SAT JUL 25 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
FORECAST CHALLENGE FOR THE SHORT TERM WILL BE POTENTIAL FOR
CONVECTION MAINLY ACROSS THE SOUTH AND DAYTIME HIGHS FOR WHAT
SHOULD BE A GENERALLY DRY WEEKEND. PREFER HIGHER RES MODELS FOR
PRECIP TRENDS THIS EVENING. A RIDGE AXIS IS CURRENTLY OVER THE
EASTERN CWA...BRINGING CALM WINDS TO MOST OF WEST CENTRAL
MINNESOTA WHILE WEAK RETURN FLOW HAS SET UP OVER EASTERN NORTH
DAKOTA AND THE NORTHERN VALLEY TO INCLUDE FAR NORTHWESTERN MN.
THIS MORNING...CALM WINDS...DEW POINTS AROUND 60 AND CLEAR SKIES
ARE RESULTING IN SOME PATCHY FOG ACROSS W CNTRL MN. HAVE PUT
PATCHY FOG INTO FCST THROUGH 13Z TO 14Z TIMEFRAME. MAY SEE SOME
IMPROVEMENT ADJACENT TO THE VALLEY AS WINDS PICK UP AND TURN
SOUTHERLY...BUT SHOULD HOLD OFF UNTIL MID MORNING BURN OFF IN
EASTERN ZONES.
RETURN FLOW WILL SET UP AND WESTERN ZONES SHOULD SEE SOME
INCREASED INSTABILITY...HOWEVER THE BEST INSTABILITY WILL
GENERALLY BE ACROSS WRN ND AND SD WITH WEAK SUBSIDENCE OVER OUR
AREA AS LOW AMPLITUDE UPPER RIDGE MOVES ACROSS AREA. MODELS ARE
SHOWING WEAK SHORTWAVES CONTINUING TO RIDE NORTHERN EDGE OF THE
UPPER RIDGE AND DEVELOP CONVECTION ACROSS SRN MANITOBA WILE A
STRONGER WAVE WILL MOVE ACROSS SD WHERE SPC HAS A SLIGHT RISK FOR
DAY 1. DEEP LAYER SHEAR CURRENTLY AROUND 40 KTS WILL WEAKEN
THROUGH THE DAY AS UPPER RIDGE MOVES ACROSS ND...WHILE WRN ND WILL
SEE AN INCREASE IN INSTABILITY BY LATE AFTN. THINK BEST CHANCE FOR
STORMS WILL BE ALONG SD BORDER OR WRN ZONES WHERE STORMS
DEVELOPING OVER WRN/CNTRL ND AND ADVECT INTO DVL AREA. ECMWF/GFS
APPEAR RATHER BULLISH FOR CONVECTION IN FAR WRN ND BUT MOST MODELS
IN AGREEMENT WITH CONVECTION DYING OFF OVERNIGHT. WILL KEEP LOW
CHANCE POPS IN THE FAR WEST/SOUTH WITH MAJORITY OF CWA DRY. ALSO
ADDED LOW POPS IN THE FAR NORTHEAST AS HRRR CONTINUES TO SHOW SOME
WEAK STORMS RIDING OVER THE RIDGE AND CROSS LAKE OF THE
WOODS...NORTHERN BELTRAMI COUNTIES.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
SUNDAY NIGHT INTO MONDAY...UPPER RIDGE OVER EASTERN ZONES WHILE
WE SLOWLY TRANSITION FROM A MORE ZONAL TO SOUTHWESTERLY FLOW
PATTERN IN THE WEST BY 00Z MON. SHOULD SEE PLENTY OF SUNSHINE AND
TEMPS AROUND 90 F FOR DAYTIME HIGHS BOTH DAYS. WILL SEE CONVECTION
BEGIN TO DEVELOP OVER ERN MT AND WRN ND LATE IN THE DAY...MOSTLY
DRY OVER OUR AREA. WEAK LOW PRESSURE OVER SASK/MB REGION WILL
INTERACT WITH A SERIES OF WEAK SHORT WAVES EMBEDDED IN SW
FLOW...AND BRING A CHANCE FOR TSTMS TO NW ZONES AND ALONG THE INTL
BORDER. A MORE SIGNIFICANT LOW PRESSURE SYSTEM THEN DEVELOPS MON
NIGHT OVER MT/WY AND WILL BRING A FRONT ACROSS THE AREA EARLY IN
THE NEXT WORK WEEK. HAVE CONTINUED LIKELY POPS IN THE FAR
NORTHWESTERN ZONES AS STORMS CONTINUE ACROSS SRN CANADA.
FOR TUE THROUGH FRI...THERE COULD BE SOME CONVECTION ON TUE
DEPENDING ON TIMING OF A FRONT THAT WILL MOVE THROUGH THE AREA.
THEREAFTER...TEMPS SHOULD COOL DOWN BELOW NORMAL BY WED. THERE COULD
BE SOME CONVECTION IN THE NORTH WED CLOSER TO CYCLONIC FLOW...BUT
OVERALL NOT EXPECTING TOO MUCH COVERAGE OF SHOWERS OR STORMS. FOR
THU/FRI...EXPECT TEMPS RISING TO AROUND NORMAL WITH MAINLY DRY
WEATHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1137 PM CDT FRI JUL 24 2015
VFR CONDITIONS THROUGH THE PERIOD...WITH LIGHT WINDS. THERE IS THE
POTENTIAL FOR FOG DEVELOPMENT TONIGHT CONSIDERING THE LIGHT WINDS
AND RECENT RAINFALL...BUT COVERAGE SHOULD BE LIMITED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...SPEICHER
LONG TERM...DK/SPEICHER
AVIATION...TG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1141 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 1141 PM CDT FRI JUL 24 2015
LATEST SUITE OF SATELLITE IMAGERY SHOWS SCT MID LEVEL CLOUDS
LOCATED IN THE NORTHEAST/TURTLE MOUNTAINS...ASSOCIATED WITH
DECAYING SHOWERS AND THUNDERSTORMS IN SOUTHERN MANITOBA...AND ALSO
IN SOUTHWEST NORTH DAKOTA WITH INCREASING MOISTURE ADVECTION AHEAD
OF A COUPLE MID LEVEL SHORTWAVE TROUGHS SHIFTING THROUGH MONTANA
AND WYOMING. GENERALLY A CLEAR SKY IN BETWEEN THESE AREAS. THE LATEST
REGIONAL RADAR SHOWS ISOLATED SHOWERS JUST SOUTH OF BOWMAN AND
HETTINGER MOVING EAST WITH TIME. FARTHER UPSTREAM INTO SOUTHEAST
MONTANA AND NORTHEAST WYOMING...A MORE DISTINCT AREA OF SHOWERS
AND THUNDERSTORMS WHICH ARE MOVING SLOWLY TO THE NORTHEAST.
FORECAST TRENDS IN AGREEMENT WITH LATEST RADAR AND 00Z DATA. A
GRADUAL INCREASE IN SHOWER/THUNDERSTORM THREAT OVERNIGHT...MOSTLY
IN THE SOUTHWEST...THEN EXPANDING INTO CENTRAL NORTH DAKOTA BY
SATURDAY AFTERNOON/EVENING. NO SIGNIFICANT UPDATES AT THIS TIME.
UPDATE ISSUED AT 908 PM CDT FRI JUL 24 2015
CONVECTION OVER THE NORTH CENTRAL HAS WEAKENED OVER THE PAST
HOUR...SO WILL LOWER POPS TO SLIGHT CHANCE...REMOVING AFTER AN
HOUR OR SO. NEXT ROUND OF WEAK WAVES CONTINUE TO SLOWLY APPROACH
FROM THE SOUTHWEST...SO WILL KEEP POPS IN FOR MAINLY LATE
TONIGHT/EARLY SATURDAY MORNING OVER THE SOUTHWEST. UPDATES HAVE
BEEN SENT.
UPDATE ISSUED AT 610 PM CDT FRI JUL 24 2015
A FEW THUNDERSTORMS CONTINUE OVER NORTHWEST NORTH DAKOTA...BUT
THESE SHOULD BE DIMINISHING SOON WITH LOSS OF DAYTIME HEATING.
OTHERWISE...A QUIET EVENING IS IN STORE FOR MOST LOCATIONS BEFORE
THE NEXT SHORT WAVE APPROACHES SOUTHWESTERN AREAS...BRINGING LOW
SHOWER/THUNDERSTORM CHANCES.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 256 PM CDT FRI JUL 24 2015
LATEST SURFACE ANALYSIS HAS A SURFACE HIGH PRESSURE REGION OVER
THE CENTRAL DAKOTAS WITHE A WEAK TROUGH OF LOW PRESSURE AND AN
ASSOCIATED DEWPOINT DISCONTINUITY ACROSS WESTERN NORTH DAKOTA. A
CU FIELD IS ASSOCIATED WITH THE DEWPOINT DISCONTINUITY. THE
FORECAST TRENDS IN THE HRRR PLACE SOME SCATTERED THUNDERSTORMS
ACROSS WESTERN NORTH DAKOTA THIS AFTERNOON/EVENING. THE NAM/GFS
ARE DRY. BUFKIT SOUNDINGS SHOW THE CAP ERODING BUT DONT THINK
THERE WILL BE ENOUGH FORCING FOR CONVECTIVE INITIATION TODAY.
WILL FOLLOW THE DRYER NAM SOLUTION THROUGH THIS EVENING.
OVERNIGHT AND SATURDAY NAM/ECMWF/GFS ALL BRING THE H500 RIDGE
THROUGH THE STATE. THIS POSITIONS AN H500 TROUGH OVER THE
NORTHWEST US TO BRING SOME SHORTWAVE ENERGY INTO THE REGION
SATURDAY. WILL TREND CHANCE POPS ACROSS THE WEST AND SLIGHT CHANCE
CENTRAL BY SATURDAY AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 256 PM CDT FRI JUL 24 2015
CHANCES OF THUNDERSTORMS THROUGH THE WEEKEND...WITH THE POTENTIAL
FOR STRONGER THUNDERSTORMS ON MONDAY. THEN A MAINLY DRY FORECAST BY
MID-WEEK.
ZONAL MID LEVEL FLOW SATURDAY AND INTO SATURDAY NIGHT KEEPS WEAK
WAVES PASSING THROUGH THE NORTHERN PLAINS WITH SMALL CHANCES FOR
THUNDERSTORMS. ON SATURDAY NIGHT THE MODELS INDICATE SCATTERED
THUNDERSTORMS MAINLY ACROSS SOUTHERN NORTH DAKOTA WITH UPPER LEVEL
SHORTWAVE ENERGY MOVING EASTWARD ACROSS SOUTH DAKOTA AND SOUTHERN
NORTH DAKOTA.
ON SUNDAY WEAK BROAD RIDGING DEVELOPS OVER NORTH DAKOTA AS A
LONGWAVE TROUGH MOVES INTO AND DIGS OFF THE WEST COAST...BUT UPPER
LEVEL ENERGY MOVING THROUGH THE UPPER LEVEL FLOW WILL KEEP A CHANCE
OF THUNDERSTORMS IN THE FORECAST.
BY MONDAY CHANCES FOR WIDESPREAD STORMS INCREASE AS THE UPPER LEVEL
LONG WAVE TROUGH MOVES ACROSS THE ROCKIES. SOUTHWEST FLOW ALOFT
AHEAD OF THE TROUGH...AND A GUSTY SOUTHERLY SURFACE FLOW WITH
SURFACE LOW PRESSURE IN THE FRONT RANGE...INCREASES MOISTURE AND
INSTABILITY. THE FORECAST CAPE AND SHEAR PARAMETERS WOULD BE
SUFFICIENT FOR A MENTION OF SEVERE STORMS. THE STORM PREDICTION
CENTER DOES INDICATE A SLIGHT CHANCE OF SEVERE STORMS OVER WESTERN
AND CENTRAL NORTH DAKOTA IN THEIR DAY 4 OUTLOOK (MONDAY AND MONDAY
NIGHT). WILL NOT MENTION SEVERE WORDING JUST YET...BUT LATER SHIFTS
WILL NEED TO TAKE A CLOSER LOOK AT THE SYNOPTIC SETUP.
ON TUESDAY THE MODELS LIFT THE LONGWAVE TROUGH NORTHEASTWARD ACROSS
NORTH DAKOTA AND INTO MANITOBA. THIS WILL KEEP A CHANCE OF SHOWERS
AND THUNDERSTORMS IN OUR AREA...BUT ALSO MOVES A STRONGER SURFACE
LOW AND COLD FRONT ACROSS THE DAKOTAS. GUSTY WEST WINDS ON TUESDAY
WILL USHER IN COOLER AIR TO OUR REGION. LOOKING AT HIGHS ON TUESDAY
AND WEDNESDAY IN THE 70S TO LOWER 80S.
MAINLY DRY THURSDAY AND FRIDAY WITH NORTHWEST FLOW ALOFT...AND HIGHS
IN THE 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1141 PM CDT FRI JUL 24 2015
VFR CIGS/VSBYS NEXT 24HR. HOWEVER A VCTS WILL BE CARRIED AT ALL
TERMINALS SATURDAY...WITH KDIK IN LINE WITH THE EARLIEST ONSET AND
BEST CHANCE FOR SHOWERS/THUNDERSTORMS. WILL BE LOOKING AT THE
POSSIBILITY HAVING SOME PREDOMINATE MENTION OF PRECIPIATION AT
SOME OF THE TERMINALS FOR THE 12Z TAF ISSUANCE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...WAA
LONG TERM...JV
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1137 PM CDT FRI JUL 24 2015
.UPDATE...
ISSUED AT 944 PM CDT FRI JUL 24 2015
SHOWERS APPROACHING FROM THE NW ARE DISSIPATING...BUT WILL KEEP
THE 20 POPS NEAR THE INTERNATIONAL BORDER UNTIL 4Z JUST IN CASE
ONE SNEAKS INTO THE REGION. FORECAST IN GOOD SHAPE AND NO CHANGES
PLANNED.
UPDATE ISSUED AT 646 PM CDT FRI JUL 24 2015
SHOWERS ACROSS THE EASTERN FA SHOULD MOVE OUT OF THE REGION BY
01Z. THERE IS ANOTHER AREA OF SHOWERS/THUNDER APPROACHING FROM THE
NORTHWEST...AND THE HRRR INDICATES ENOUGH FORCING TO HOLD THIS
ACTIVITY TOGETHER SO THAT IT CAN REACH THE DVL BASIN 01Z-04Z..AND
DID INSERT ISOLD POPS FOR THIS TIMEFRAME.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 308 PM CDT FRI JUL 24 2015
EXPECT A WARM WEEKEND OVER THE AREA WITH HIGHS WELL INTO THE
80S AS A BROAD UPPER RIDGE WILL BE IN PLACE. THE USUAL WEAK SHORT
WAVES WILL MOVE THROUGH THE AREA...BUT MAINLY IMPACT SOUTH DAKOTA
SATURDAY NIGHT AS AN UPPER WAVE MOVES THROUGH AND INTERACTS WITH A
WEAK LOW LEVEL JET. MODELS ALL OVER THE PLACE WITH PCPN PLACEMENT.
GEM TOO FAR NORTH OVER SE ND AND NAM/GFS MORE OVER FAR NRN SD AND
THE ECMWF A BIT FARTHER SOUTH. NET RESULT WAS TO KEEP CHC POPS IN
SRN FCST AREA SAT NIGHT. UNTIL THEN DRY TONIGHT INTO MOST OF
SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 PM CDT FRI JUL 24 2015
SHORT WAVE MOVES EAST SUNDAY WITH ANY PCPN CHANCES ENDING IN
WCNTRL MN SUNDAY MORNING. SUNDAY WILL BE VERY WARM AND HUMID WITH
HIGHS CLOSE TO 90 IN IN THE SRN VALLEY. WARM AND HUMID INTO
MONDAY. THERE COULD BE AN ISOLD STORM SUN-SUN NIGHT BUT NOT A
CLEAR SIGNAL IN MODELS BUT PATTERN WOULD SUPPORT SOME AFTN HEATING
STORMS AND A LINGERING STORM OR TWO SUNDAY NIGHT. MONDAY WILL
FEATURE A BUILDING 500 MB RIDGE EAST OF A PRETTY STRONG UPPER
TROUGH OVER WRN MONTANA. WILL MAINTAIN SOME CHC POPS MONDAY BUT
MAIN FOCUS WILL BE IN ERN MT/WRN ND MONDAY.
MONDAY NIGHT TO FRIDAY...MODELS CONTINUE TO BRING A STRONG UPPER
WAVE ALONG THE INTERNATIONAL BORDER ON TUESDAY AND WEDNESDAY.
AHEAD OF THIS FEATURE A HOT AND HUMID AIRMASS WILL BE IN PLACE ON
TUESDAY MORNING...THAT WILL FUEL THUNDERSTORM DEVELOPMENT AS THE
SYSTEM ENHANCES LIFT ACROSS THE DAKOTAS TUESDAY. UNCERTAINTY
EXISTS WITH THE STRENGTH OF THE CAP AND SOUTHERN EXTENT OF PRECIP.
FROPA PASSES EAST ON WEDNESDAY WITH BEST CHANCES FOR THUNDER ALONG
THE NORTHERN TIER...WHERE COLDER TEMPS LOFT RESIDE. WEDNESDAY TO
FRIDAY WILL BE OVERALL DRY WITH TEMPS IN THE UPR 70S TO LOW
80S...AT TO SLIGHTLY BELOW END OF JULY NORMALS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1137 PM CDT FRI JUL 24 2015
VFR CONDITIONS THROUGH THE PERIOD...WITH LIGHT WINDS. THERE IS THE
POTENTIAL FOR FOG DEVELOPMENT TONIGHT CONSIDERING THE LIGHT WINDS
AND RECENT RAINFALL...BUT COVERAGE SHOULD BE LIMITED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...RIDDLE
LONG TERM...JK/RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION
NWS TULSA OK
1149 PM CDT FRI JUL 24 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 6Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL SITES THROUGHOUT
THE 24 HOUR FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 908 PM CDT FRI JUL 24 2015/
..UPDATE...
DISCUSSION...
AREA OF THUNDERSTORMS OVER SOUTH CENTRAL MISSOURI WILL MAKE A
CLOSE APPROACH TO PARTS OF FAR NORTHWEST ARKANSAS...BUT WITH
RECENT RADAR TRENDS INDICATING A DISSIPATING TREND ON THE
NORTHWEST EDGE NEAR SPRINGFIELD AND ALSO WARMING CLOUD TOPS IN
SATELLITE IMAGERY...CURRENT THINKING IS THAT THE STORMS WILL MISS
THE FORECAST AREA ENTIRELY. THIS IS FAIRLY WELL DEPICTED IN THE
LATEST HRRR GUIDANCE AS WELL. FOR THESE REASONS...WILL NOT PUT ANY
MENTIONABLE POPS IN THE ONGOING FORECAST.
OVERALL...THE FORECAST LOOKS WELL IN HAND...WITH OVERNIGHT LOWS
BEING VERY NEAR LAST NIGHTS. EARLIER UPDATE ADDRESSED THE
EXPIRATION OF THE AFTERNOON HEAT HEADLINES...AND NO FURTHER UPDATE
IS PLANNED AT THIS TIME.
PREV DISCUSSION... /ISSUED 600 PM CDT FRI JUL 24 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 0Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL SITES THROUGHOUT
THE 24 HOUR FORECAST PERIOD.
PREV DISCUSSION... /ISSUED 352 PM CDT FRI JUL 24 2015/
DISCUSSION...
A RIDGE OF HIGH PRESSURE REMAINS THE DOMINATE FEATURE ACROSS THE
SOUTHERN PLAINS THIS AFTERNOON. THIS HAS ALLOWED FOR SOUTH TO
SOUTHWESTERLY LOW LEVEL FLOW TO TRANSPORT HOT TEMPERATURES ON TOP
OF DEWPOINTS IN THE 70S ACROSS MUCH OF EASTERN OKLAHOMA AND
NORTHEAST ARKANSAS. THE RESULTS ARE MOSTLY SUNNY SKIES...HOT AND
HUMID CONDITIONS AND HEAT INDICES AROUND 105 DEGREES TO AROUND
112 DEGREES OVER THE CWA. THUS...WILL LET THE CURRENT HEAT
HEADLINES RIDE AS IS THROUGH MID EVENING.
THE RIDGE REMAINS INTACT OVER THE SOUTHERN PLAINS THROUGH THE
WEEKEND AND INTO THE FIRST HALF OF NEXT WEEK. THE CENTER OF THE
HIGH PRESSURE LOOKS TO OSCILLATE A BIT FROM WEST TO EAST AND BACK
THROUGH TUESDAY OF NEXT WEEK...WHICH COULD ALLOW FOR A DIFFERENCE
OF A DEGREE OR SO IN SURFACE TEMPS EACH DAY. HOWEVER...WITH 850-MB
IN THE LOW TO MID +20C RANGE...HIGH TEMPS IN THE MID 90S FOR FAR
NORTHWEST ARKANSAS TO THE UPPER 90S/NEAR 100 DEGREES WILL REMAIN
COMMON ELSEWHERE OVER THE CWA THROUGH TUESDAY. THUS...HAVE
EXTENDED THE HEAT ADVISORY INTO SATURDAY AFTERNOON FOR MOST
LOCATIONS AND WILL PROBABLY HAVE TO EXTEND AGAIN FOR SUNDAY AND
MONDAY. HEAT INDICES OF AROUND 105 TO 110 DEGREES ARE FORECAST.
IN THE EXTENDED FORECAST...THE RIDGE OF HIGH PRESSURE LOOKS TO
FINALLY SHIFT FAR ENOUGH WEST FOR THE SECOND HALF OF NEXT WEEK TO
ALLOW FOR NORTHWESTERLY FLOW TO RETURN OVER THE PLAINS. THIS COULD
ALLOW FOR A WAVE...FORECAST TO MOVE INTO THE PACIFIC NORTHWEST
THIS WEEKEND...TO DROP A FRONTAL BOUNDARY AND RAIN CHANCES INTO
THE REGION THURSDAY/FRIDAY OF NEXT WEEK. THIS COULD BRING A BRIEF
RELIEF FROM THE HOT AND HUMID CONDITIONS...THOUGH WE WILL JUST
HAVE TO WAIT AND SEE...
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY FROM NOON TO 8 PM CDT SATURDAY FOR OKZ049-053>076.
AR...HEAT ADVISORY FROM NOON TO 8 PM CDT SATURDAY FOR ARZ001-002-019-
020-029.
&&
$$
AVIATION...06
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1234 AM CDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 1232 AM CDT SAT JUL 25 2015
SEE UPDATED AVIATION DISCUSSION BELOW.
UPDATE ISSUED AT 845 PM CDT FRI JUL 24 2015
SOME ELEVATED CONVECTION ALREADY DEVELOPING OUT WEST THIS EVENING
AND MOVING EAST. EXPECT THIS DEVELOPMENT TO CONTINUE THROUGH THE
NIGHT AS SHOWN BY THE HRRR MODEL. IT SHOULD REMAIN WEST OF THE
JAMES RIVER VALLEY. ADJUSTED WEATHER AND POPS FOR THE NIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 247 PM CDT FRI JUL 24 2015
THERE ARE A NUMBER OF FORECAST CHALLENGES IN THE SHORT TERM
REGARDING THUNDERSTORM CHANCES AND SEVERE POTENTIAL. MODELS ARE IN
GENERAL AGREEMENT ON THE OVERALL SYNOPTIC PATTERN BUT THERE ARE SOME
SIGNIFICANT DIFFERENCES IN PLACEMENT/TIMING ON THE NEW 12Z RUNS
BETWEEN THE HI-RES CAMS AND THE GLOBAL MODELS. THE ECMWF IS ALSO
FARTHER SOUTH THAN PREVIOUS SOLUTIONS WHILE THE GFS ENHANCED THE
EASTERN H5 SHORTWAVE SAT EVENING AND THEREFORE KEEPS A RATHER ROBUST
QPF FIELD ACROSS THE EASTERN CWA.
STUCK WITH THE HI-RES SOLUTIONS THIS EVENING WHICH GENERATE SOME
STORMS WEST RIVER BY 0Z. WHILE CAPE IS UNDERWHELMING..LESS THAN 1000
J/KG ON THE RAP...UNTIL CLOSE TO 12Z SAT SHEAR IS AROUND 45 TO 55
KTS AND CIN IS MINIMAL. THESE STORMS WILL NOT MIGRATE VERY FAR EAST
UNTIL CLOSER TO MORNING. ANY LEFT OVER CLOUDINESS MAY HAMPER INITIAL
RE-DEVELOPMENT SAT AFTERNOON AS A STRONG SHORTWAVE BEGINS TO MOVE
FROM WEST TO EAST ACROSS THE SOUTHERN CWA. SHEAR IN THE BAROCLINIC
ZONE WILL BE SUFFICIENT FOR ANY STORMS THAT DO DEVELOP TO BECOME
SEVERE.
MOST OF THE DAY SUNDAY WILL BE DRY IN BETWEEN SYSTEMS. THERE IS AN
APPROACHING SFC LOW AND SOME WEAKER SHORTWAVE ENERGY SUNDAY EVENING
THAT MAY FIRE OFF A FEW STORMS BUT MODELS DIVERGE GREATLY ON
PLACEMENT WITH SOME KEEPING ANY PRECIP CHANCE OUT OF THIS CWA.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 247 PM CDT FRI JUL 24 2015
SLIGHT PRECIP CHANCES REMAIN IN THE FORECAST FOR EARLY IN THE
WORKWEEK AS AN UPPER LEVEL TROUGH MOVES OUT OF THE PACIFIC
NORTHWEST...ALTHOUGH 700 MB TEMPERATURES RANGING FROM 12 C TO 16 C
WILL KEEP A CAP ON MOST CONVECTION. NORTHWEST FLOW BEHIND THE TROUGH
WILL THEN BRING COOLER AND DRIER CONDITIONS BY MID WEEK...AS WELL AS
GUSTY WINDS. THIS WILL BE SHORT LIVED HOWEVER...AS 500 MB HEIGHTS
ARE ON THE RISE BY THE END OF THE WORKWEEK...WITH FORECAST MAX
TEMPERATURES BACK IN THE UPPER 80S AND 90S BY FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1232 AM CDT SAT JUL 25 2015
VFR CONDITIONS ARE EXPECTED AT ALL LOCATIONS THROUGH TONIGHT AND
SATURDAY. A COUPLE ROUNDS OF THUNDERSTORMS ARE EXPECTED INTO
SATURDAY EVENING. THE FIRST ROUND OF STORMS OUT WEST COULD AFFECT
PIR AND MBG TONIGHT. THE NEXT ROUND WILL COME SATURDAY AFTERNOON
AND EVENING POSSIBLY AFFECTING ALL LOCATIONS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...WISE
LONG TERM...SERR
AVIATION...PARKIN
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
141 AM EDT SAT JUL 25 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION OVERNIGHT AND WILL
REMAIN OVER THE AREA THROUGH THE WEEKEND. A BACKDOOR COLD FRONT
WILL MOVE INTO THE AREA SUNDAY NIGHT AND MONDAY...THEN STALL...AND
BE A FOCUS FOR SHOWERS AND THUNDERSTORMS INTO AT LEAST TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 100 AM EDT SATURDAY...
MADE SOME MINOR ADJUSTMENTS TO TEMPERATURES AND CLOUD COVER FOR
EARLY THIS MORNING.
AS OF 822 PM EDT FRIDAY...
OTHER THAN FOR A FEW SPRINKLES ALONG THE FAR SOUTHERN BLUE
RIDGE...QUIET WEATHER PREVAILS THIS EVENING AND LOOKS TO CONTINUE
OVERNIGHT UNDER HIGH PRESSURE AND VERY DRY AIR ALOFT PER EVENING
SOUNDINGS. HOWEVER STILL SOME CONCERN ABOUT SOME LOW TOPPED
SHOWERS FORMING ACROSS THE SW UNDER THE MID LEVEL INVERSION
THROUGH LATE THIS EVENING AS MIXING WEAKENS AND MOISTURE POOLS A
BIT. ALSO SEEING A DECENT LOW LEVEL THETA-E RIDGE UP ALONG THE
BLUE RIDGE WHICH THE HRRR KEEPS FOCUS ALONG AS CU SPREADS OUT
UNDER THE DRY AIR ABOVE AFTER LOSS OF HEATING. SINCE THIS SOLUTION
HAS BEEN OVERDONE WILL ONLY KEEP AN ISOLATED MENTION GOING SOUTHERN
BLUE RIDGE A FEW MORE HOURS WITH PC TO CLEAR ELSW. OTHER CONCERN
WITH POSSIBLE FORMATION OF LOW CLOUDS EASTERN SLOPES LATE...AND
EXPANSE OF FOG BY FORMATION BY DAWN ESPCLY VALLEYS AND OUT EAST
WHERE DEWPOINTS ARE HIGHER. LATEST GUIDANCE STILL SUPPORTS QUITE A
BIT OF FOG SO INCLUDED SOME AREAS OF DENSE FOG VALLEYS AND LEFT
MUCH OF THE REST OF THE CWA IN PATCHY COVERAGE. OTRW BUMPED DOWN
LOW TEMPS A LITTLE IN THE WEST WHILE RAISING SOME SE BUT OVERALL
60S WITH A FEW 50S DEEPER VALLEYS.
PREVIOUS DISCUSSION AS OF 305 PM EDT FRIDAY...
UPPER LEVEL TROUGHINESS AND LOW LEVEL MOISTURE WILL KEEP MOSTLY
CLOUDY SKIES IN THE REGION THROUGH EARLY THIS EVENING. WITH LOSE OF
HEATING...CLOUDS WILL FADE THROUGH THE REST OF THE EVENING. AN
INVERSION WILL DEVELOP OVERNIGHT AS SURFACE HIGH PRESSURE BUILDS IN
FROM THE OHIO VALLEY. MOISTURE TRAPPED UNDER THIS INVERSION MAY
BRING A LOW STRATUS DECK OVER THE AREA AND LINGER THROUGH SATURDAY
MORNING. AREAS NOT BEING OVERCOME BY THIS STRATUS DECK WILL LIKELY
HAVE PATCHY MORNING FOG...ESPECIALLY IN MOUNTAIN VALLEYS AND LOW
LYING AREAS. THIS FOG WILL BURN OFF QUICKER THAN THE STRATUS DECK
WILL. LIKE THIS AFTERNOON...UPPER LEVEL TROUGHINESS AND LOW LEVEL
MOISTURE WILL KEEP MOSTLY CLOUDY SKIES WITH TEMPERATURES NEAR
NORMAL. THE CHANCE FOR RAIN IS SMALL BUT POSSIBLE TOWARDS THE
EASTERN SLOPES OF THE NORTHWEST NORTH CAROLINA BLUE RIDGE. IT
APPEARS SOUTHEASTERLY UPSLOPE WINDS MAY HAVE ENOUGH MOISTURE TO
PRODUCE A FEW ISOLATED SHOWERS LATE IN THE AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
AS OF 318 PM EDT FRIDAY...
YOU CAN EXPECT TYPICAL SUMMER WX INTO SUNDAY...WITH WEAK BACKDOOR
FRONT TRYING TO MAKE IT INTO THE AREA MONDAY...BEFORE LIFTING NE
MONDAY NIGHT. THIS BOUNDARY PLUS SOME ENERGY ALOFT MAY ALLOW FOR
SCATTERED STRONGER STORMS TO FORM MONDAY...BUT STILL MOST AREAS WILL
BE DRY. KEPT POPS IN THE LOW CHANCE RANGE...WITH LESS COVERAGE
SUNDAY.
HIGHS SUNDAY-MONDAY WILL BE CLOSE TO NORMAL FROM THE LOWER TO MID
80S WEST TO UPPER 80S-LOWER 90S EAST.
LOW TEMPS WILL BE CREEPING BACK UP WITH HUMIDITY EXPECTED TO
INCREASE. LOWS SAT NIGHT WILL BE IN THE LOWER TO MID 60S MOUNTAINS
TO UPPER 60S EAST WARMING TO THE MID 60S MTNS SUNDAY AND MONDAY
NIGHT TO AROUND 70 EAST.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 138 PM EDT FRIDAY...
A BROAD UPPER RIDGE WILL STAY SITUATED FROM THE SOUTHERN PLAINS
EASTWARD TO THE CENTRAL AND SOUTHERN APPALACHIANS THROUGH LATE
WEDNESDAY NIGHT. THIS WILL KEEP US A BIT ON THE HUMID SIDE WITH
CLOSE TO SEASONAL TEMPS...HIGHS 80S MOUNTAINS TO LOW 90S EAST...WITH
ONLY A SCATTERING OF THUNDERSTORMS MAINLY DURING THE AFTERNOON/EARLY
EVENING PERIODS.
AS WE HEAD INTO THURSDAY AND FRIDAY...CLOSED LOW OVER THE CANADIAN
PRAIRIES EARLY IN THE PERIOD OPENS UP AS IT MOVES EAST INTO ONTARIO
AND QUEBEC. MODELS ARE FAVORING HEIGHTS LOWERING OVER THE MID
ATLANTIC DURING THIS TIME FRAME WITH A FRONTAL BOUNDARY MAKING
INROADS INTO THE MOUNTAINS BY FRIDAY AFTERNOON. THIS WILL START TO
INCREASE THE THREAT OF STORMS. AT THE MOMENT WILL ONLY ADVERTISE THE
USUAL CHANCE RANGE OF 30-50 PERCENT...BUT THINK NEXT FRIDAY WOULD
START TO FAVOR HIGHER POPS. TEMPS SHOULD FALL OFF SLIGHTLY...BUT
STILL THINK WITH FRONTAL BOUNDARY TO THE NORTHWEST...WE SHOULD STILL
SEE 80S MOUNTAINS TO NEAR 90 SOUTHEAST.
LOWS DURING THE PERIOD WILL BE IN THE LOWER TO MID 60S MOUNTAINS TO
UPPER 60S AROUND 70 EAST.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 130 AM EDT SATURDAY...
EAST SOUTHEASTERLY WINDFLOW WILL GENERATE PATCHY STRATUS
ALONG AND EAST OF THE BLUE RIDGE THIS MORNING. WITH LIGHT WINDS
AND LOW LEVEL MOISTURE WILL CREATE POCKETS OF FOG THIS MORNING.
MID AND HIGH CLOUDS WILL HINDER FOG THIS MORNING. BUT...STILL
BELIEVE THAT WE WILL SEE DEVELOPMENT OF RIVER VALLEY FOG FOR
KLWB. PATCHY LIGHT FOG IS ALSO POSSIBLE AT DAN...AND BCB.
ANY MORNING FOG WILL BURN OFF QUICKLY BY LATE MORNING.
HIGH PRESSURE WILL REMAIN IN CONTROL TODAY...WITH DAYTIME HEATING
ERODING ANY SUB VFR CONDITIONS QUICKLY AFTER 25/13Z. EARLY
AFTERNOON WILL BRING REDEVELOPMENT OF CU FIELD ACROSS THE AREA...
WITH PERHAPS A FEW SHOWERS/ISOLATED BRIEF THUNDERSTORMS DEVELOPING
ALONG THE RIDGES WITH HEATING. COVERAGE WILL BE TOO LIMITED FOR
MENTION IN TAF.
HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE
TAF PERIOD.
EXTENDED AVIATION FORECAST...
HIGH PRESSURE SHOULD STAY IN CONTROL OVERHEAD...AND MAINTAIN MAINLY
VFR CONDITIONS THROUGH THE REMAINDER OF THIS WEEKEND OUTSIDE OF
EARLY MORNING VALLEY FOG. SHOWER OR THUNDERSTORM ACTIVITY MAY
BECOME MORE ENHANCED BY MONDAY AND TUESDAY...WITH A BACKDOOR COLD
FRONT APPROACHING FROM THE COAST. A RETURN OF HAZY...HOT...AND
HUMID CONDITIONS APPEARS LIKELY BY THE MIDDLE OF THE WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RCS
NEAR TERM...JH/RCS
SHORT TERM...WP
LONG TERM...WP
AVIATION...KK/NF/PW
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
432 AM CDT SAT JUL 25 2015
.TODAY...FORECAST CONFIDENCE IS MEDIUM.
EARLIER SCATTERED TO ISOLATED CONVECTION UPSTREAM OVER WEST
CENTRAL WI DIED OUT AS IT MOVED INTO INCREASING CONVECTIVE
INHIBITION OVER SOUTHERN AND EASTERN WI...REFLECTED IN CAP BETWEEN
800 MB AND 700 MB ON BLUE RIVER RAP FORECAST SOUNDING.
THE INHIBITION DOES LOWER IN A CORRIDOR COINCIDENT WITH THE
SURFACE FRONT WITH A FEW CELLS POPPING UP ALONG THE FRONT...BUT
THEY ARE WEAK AND SHORT-LIVED WITH THE CAP AND LITTLE IN THE WAY
OF UPPER SUPPORT WITH AREA UNDER THE RIGHT EXIT REGION OF A 300 MB
JET MAXIMA AND CVA WITH THE SHORT WAVE DRIVING THE CONVECTION OVER
NE WI TO NRN LAKE MICHIGAN.
WITH HI-RES/RAPID UPDATE MODELS STILL SHOWING POTENTIAL OF
SCATTERED TO ISOLATED SHOWERS WITH A STORM OR TWO AS FRONT CROSSES
FORECAST AREA WILL KEEP A COLLABORATIVE SLIGHT CHANCE ALONG THE
FRONT...EXITING TO THE SOUTHEAST BY 15Z THOUGH A DRY FRONTAL
PASSAGE IS A STRONG POSSIBILITY.
HIGH PRESSURE SETTLES OVER THE REGION BUT MODELS STILL SHOW 925
MB TEMPS A FEW DEGREES WARMER THAN FRIDAY. WILL KEEP UPPER 80S
HIGHS INLAND WITH A COOLING LAKE BREEZE DEVELOPING BY EARLY
AFTERNOON HOLDING HIGHS IN THE UPPER 70S TO LOW 80S ALONG THE
LAKE.
.TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
FRONT STALLS TO THE SOUTH...WITH MODELS DEPICTING A SHORT WAVE
APPROACHING FROM THE WEST...WITH A CONSENSUS POSITION OVER SRN
MN/NRN IA BY 12Z SUNDAY. BETTER RETURN FLOW STAYS WEST OF CWA
THROUGH 12Z SUNDAY...BUT WITH SOME OMEGA AND ELEVATED CAPE SHOWN
ON NAM DBQ FORECAST SOUNDINGS AFTER 09Z...THOUGH LITTLE OMEGA AND
CAPE ON BLUE RIVER SOUNDING... WILL HAVE SLIGHT CHANCE POPS AFTER
09Z IN THE FAR SW CWA. LOWS IN THE MID 60S.
.SHORT TERM...SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
MODELS ARE IN DECENT AGREEMENT WITH A 500 MB RIDGE AXIS BUILDING
ACROSS THE UPPER MIDWEST REGION SUNDAY AND SUNDAY NIGHT...SHIFTING
SLOWLY EASTWARD MONDAY INTO MONDAY NIGHT. MODELS SHOWING SEVERAL
WEAK VORTICITY MAXIMA MOVING THROUGH THE REGION...WITH SOME TIMING
AND PLACEMENT DIFFERENCES. HIGH PRESSURE AT THE SURFACE REMAINS
EAST OF THE AREA DURING THE SHORT TERM PERIOD.
THE NAM/CANADIAN/ECMWF MODELS KEEP MOST PRECIPITATION TO THE WEST
AND SOUTH OF THE AREA DURING THIS TIME...WITH THE INFLUENCE OF THE
HIGH. THE GFS IS THE ONLY MODEL TO PRODUCE ROUNDS OF QPF AT TIMES
DURING THIS PERIOD. GFS FORECAST SOUNDINGS APPEAR TO BE OVERDONE
SOMEWHAT WITH DEW POINTS...WHICH MAY BE LEADING TO THE QPF
FORECASTS. THINK THE GFS IS OVERDONE...AS THERE ARE NO SIGNIFICANT
FEATURES TO PRODUCE THE QPF IT IS SHOWING.
THUS...LEANED TOWARDS THE NAM/CANADIAN/ECMWF AND LOWERED POPS
DURING THE SHORT TERM PERIOD. WOULD NOT BE SURPRISED TO SEE THIS
PERIOD END UP DRY. WARM 925 MB TEMPERATURES AND SOME SUNSHINE
SHOULD RESULT IN WARM AND HUMID DAYS SUNDAY AND MONDAY...WITH
HIGHS INTO THE MIDDLE TO UPPER 80S EACH DAY. THEY COULD INCH A
DEGREE OR TWO HIGHER THAN CURRENTLY FORECAST. ONSHORE WINDS WILL
KEEP LAKESHORE AREAS SOMEWHAT COOLER.
.LONG TERM...TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF MODELS ARE IN DECENT AGREEMENT WITH WARM AND HUMID
CONDITIONS LINGERING TUESDAY INTO TUESDAY NIGHT...BEFORE A COLD
FRONT MOVES THROUGH THE REGION LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. A BROAD 500 MB TROUGH PASSES THROUGH THE REGION WEDNESDAY
AS WELL...WITH EMBEDDED VORTICITY MAXIMA. THUS...KEPT POPS GOING
FOR THE TUESDAY INTO WEDNESDAY PERIOD...HIGHEST TUESDAY NIGHT. MAY
NEED HIGHER POPS TUESDAY NIGHT/EARLY WEDNESDAY IF THEY REMAIN
CONSISTENT WITH THE FRONTAL PASSAGE TIMING.
SOMEWHAT COOLER AND LESS HUMID CONDITIONS THEN MOVE INTO THE
REGION FOR LATER WEDNESDAY INTO FRIDAY ACROSS THE REGION...AS
HIGH PRESSURE MOVES INTO THE CENTRAL PLAINS. MOST OF THIS PERIOD
LOOKS DRY AT THIS TIME.
.AVIATION/12Z TAFS/...
EXCEPT FOR A FEW BRIEF ISOLATED SHOWERS/SPRINKLES POPPING UP
ALONG THE COOL FRONT...MOST AREAS LOOK TO REMAIN DRY AS THE FRONT
MOVES THROUGH THE AREA. WILL REMOVE VICINITY THUNDER AS ANY PCPN
THAT DOES REACH A TAF SITE WILL BE A LIGHT SHOWER AT MOST. FRONT
CLEARS THE FAR SOUTHEAST CORNER BETWEEN 15Z AND 16Z ENDING ANY
PCPN CHANCES.
MAINLY VFR CLOUDS WITH FRONT...BUT SOME SCT-BKN MVFR CLOUDS RIGHT
BEHIND THE FRONT THAT COULD AFFECT TAF SITES FOR AN HOUR OR TWO
AFTER FRONTAL PASSAGE. WILL WATCH TRENDS UP TO ISSUANCE TO SEE IF
LOWER CLOUDS EXPAND IN COVERAGE.
VFR CONDITIONS FOR REMAINDER OF FORECAST WITH AN EASTERLY LAKE
BREEZE DEVELOPING EARLY THIS AFTERNOON THAT SHOULD PUSH WEST TO
KUES BY LATE AFTERNOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
SUNDAY THROUGH FRIDAY...WOOD
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
330 AM CDT SAT JUL 25 2015
.TODAY...FORECAST CONFIDENCE IS MEDIUM.
EARLIER SCATTERED TO ISOLATED CONVECTION UPSTREAM OVER WEST
CENTRAL WI DIED OUT AS IT MOVED INTO INCREASING CONVECTIVE
INHIBITION OVER SOUTHERN AND EASTERN WI...REFLECTED IN CAP BETWEEN
800 MB AND 700 MB ON BLUE RIVER RAP FORECAST SOUNDING.
THE INHIBITION DOES LOWER IN A CORRIDOR COINCIDENT WITH THE
SURFACE FRONT WITH A FEW CELLS POPPING UP ALONG THE FRONT...BUT
THEY ARE WEAK AND SHORT-LIVED WITH THE CAP AND LITTLE IN THE WAY
OF UPPER SUPPORT WITH AREA UNDER THE RIGHT EXIT REGION OF A 300 MB
JET MAXIMA AND CVA WITH THE SHORT WAVE DRIVING THE CONVECTION OVER
NE WI TO NRN LAKE MICHIGAN.
WITH HI-RES/RAPID UPDATE MODELS STILL SHOWING POTENTIAL OF
SCATTERED TO ISOLATED SHOWERS WITH A STORM OR TWO AS FRONT CROSSES
FORECAST AREA WILL KEEP A COLLABORATIVE SLIGHT CHANCE ALONG THE
FRONT...EXITING TO THE SOUTHEAST BY 15Z THOUGH A DRY FRONTAL
PASSAGE IS A STRONG POSSIBILITY.
HIGH PRESSURE SETTLES OVER THE REGION BUT MODELS STILL SHOW 925
MB TEMPS A FEW DEGREES WARMER THAN FRIDAY. WILL KEEP UPPER 80S
HIGHS INLAND WITH A COOLING LAKE BREEZE DEVELOPING BY EARLY
AFTERNOON HOLDING HIGHS IN THE UPPER 70S TO LOW 80S ALONG THE
LAKE.
.TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
FRONT STALLS TO THE SOUTH...WITH MODELS DEPICTING A SHORT WAVE
APPROACHING FROM THE WEST...WITH A CONSENSUS POSITION OVER SRN
MN/NRN IA BY 12Z SUNDAY. BETTER RETURN FLOW STAYS WEST OF CWA
THROUGH 12Z SUNDAY...BUT WITH SOME OMEGA AND ELEVATED CAPE SHOWN
ON NAM DBQ FORECAST SOUNDINGS AFTER 09Z...THOUGH LITTLE OMEGA AND
CAPE ON BLUE RIVER SOUNDING... WILL HAVE SLIGHT CHANCE POPS AFTER
09Z IN THE FAR SW CWA. LOWS IN THE MID 60S.
.SHORT TERM...SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE IS
MEDIUM.
MODELS ARE IN DECENT AGREEMENT WITH A 500 MB RIDGE AXIS BUILDING
ACROSS THE UPPER MIDWEST REGION SUNDAY AND SUNDAY NIGHT...SHIFTING
SLOWLY EASTWARD MONDAY INTO MONDAY NIGHT. MODELS SHOWING SEVERAL
WEAK VORTICITY MAXIMA MOVING THROUGH THE REGION...WITH SOME TIMING
AND PLACEMENT DIFFERENCES. HIGH PRESSURE AT THE SURFACE REMAINS
EAST OF THE AREA DURING THE SHORT TERM PERIOD.
THE NAM/CANADIAN/ECMWF MODELS KEEP MOST PRECIPITATION TO THE WEST
AND SOUTH OF THE AREA DURING THIS TIME...WITH THE INFLUENCE OF THE
HIGH. THE GFS IS THE ONLY MODEL TO PRODUCE ROUNDS OF QPF AT TIMES
DURING THIS PERIOD. GFS FORECAST SOUNDINGS APPEAR TO BE OVERDONE
SOMEWHAT WITH DEW POINTS...WHICH MAY BE LEADING TO THE QPF
FORECASTS. THINK THE GFS IS OVERDONE...AS THERE ARE NO SIGNIFICANT
FEATURES TO PRODUCE THE QPF IT IS SHOWING.
THUS...LEANED TOWARDS THE NAM/CANADIAN/ECMWF AND LOWERED POPS
DURING THE SHORT TERM PERIOD. WOULD NOT BE SURPRISED TO SEE THIS
PERIOD END UP DRY. WARM 925 MB TEMPERATURES AND SOME SUNSHINE
SHOULD RESULT IN WARM AND HUMID DAYS SUNDAY AND MONDAY...WITH
HIGHS INTO THE MIDDLE TO UPPER 80S EACH DAY. THEY COULD INCH A
DEGREE OR TWO HIGHER THAN CURRENTLY FORECAST. ONSHORE WINDS WILL
KEEP LAKESHORE AREAS SOMEWHAT COOLER.
.LONG TERM...TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF MODELS ARE IN DECENT AGREEMENT WITH WARM AND HUMID
CONDITIONS LINGERING TUESDAY INTO TUESDAY NIGHT...BEFORE A COLD
FRONT MOVES THROUGH THE REGION LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. A BROAD 500 MB TROUGH PASSES THROUGH THE REGION WEDNESDAY
AS WELL...WITH EMBEDDED VORTICITY MAXIMA. THUS...KEPT POPS GOING
FOR THE TUESDAY INTO WEDNESDAY PERIOD...HIGHEST TUESDAY NIGHT. MAY
NEED HIGHER POPS TUESDAY NIGHT/EARLY WEDNESDAY IF THEY REMAIN
CONSISTENT WITH THE FRONTAL PASSAGE TIMING.
SOMEWHAT COOLER AND LESS HUMID CONDITIONS THEN MOVE INTO THE
REGION FOR LATER WEDNESDAY INTO FRIDAY ACROSS THE REGION...AS
HIGH PRESSURE MOVES INTO THE CENTRAL PLAINS. MOST OF THIS PERIOD
LOOKS DRY AT THIS TIME.
&&
.AVIATION/12Z TAFS/...TO BE ADDED SHORTLY...
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
SUNDAY THROUGH FRIDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1140 PM CDT FRI JUL 24 2015
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 207 PM CDT FRI JUL 24 2015
IMMEDIATE CONCERN IS SEVERE CONVECTION POTENTIAL THIS EVENING WITH
COLD FROPA.
SURFACE MAP THIS AFTERNOON SHOWS THE COLD FRONT EXTENDING FROM THE
ARROWHEAD OF MN THROUGH NORTHWEST WI INTO SOUTHEAST MN INTO NORTH
CENTRAL IA. RAP PUSHES CORRIDOR OF 0-1KM MUCAPE IN THE 1500-3000J/KG
RANGE (NE-SE RESPECTIVELY) ALONG THE FRONT AS IT MOVES INTO THE AREA
BY 7PM. HOWEVER...RAP/NAM SOUNDING CONTINUE TO SHOW A STRONG 700-
800MB CAP IN PLACE TO INHIBIT SURFACE BASED CONVECTION. THE ONLY
MODEL SHOWING CONVECTIVE REFLECTIVITY OUTPUT WITH THE FROPA IS THE
NAM...BUT THIS IS WITH MUCH HIGHER PROGGED DEW POINTS IN THE 75-80
DEGREE RANGE WHICH SEEMS A BIT OVERDONE. AS A RESULT...CONVECTION
ALONG THE FRONT WILL BE VERY CONDITIONAL DUE TO THE CAP IN PLACE. IF
THE CAP DOES WEAKEN SOME...SCATTERED STRONG TO SEVERE STORMS COULD
FIRE WITH LARGE HAIL AND DAMAGING WINDS BEING THE MAIN THREAT. AS A
RESULT OF THE CONDITIONAL NATURE TO THIS SCENARIO...KEEPING POP
CATEGORY IN THE CHANCE RANGE...WITH HIGHER PROBABILITIES OVER THE
EAST WHERE CAP WILL BE WEAKEST. LOOK FOR STORM THREAT TO SUBSIDE
AFTER MIDNIGHT AS THE FRONT EXITS THE AREA.
SATURDAY LOOKS LIKE A DRIER DAY AS HIGH PRESSURE/SUBSIDENCE TAKES
CONTROL ACROSS THE AREA. PLAN ON HIGHS IN THE 80S.
SHOWER/THUNDERSTORM CHANCES RETURN LATE SATURDAY NIGHT/AFTER
MIDNIGHT AS A SHORTWAVE TROUGH ROUNDS THE TOP OF THE HEAT RIDGE IN
PLACE ACROSS THE PLAINS. NAM MOST AGGRESSIVE WITH THIS FEATURE WHILE
THE ECMWF IS MUCH WEAKER AND FARTHER SOUTH. WILL GO WITH 20-40 PPS
FOR NOW AND MAINLY WEST OF THE MISSISSIPPI RIVER.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 207 PM CDT FRI JUL 24 2015
LOOK FOR THAT MID-LEVEL TROUGH TO CONTINUE PUSHING EAST INTO/THROUGH
THE AREA SUNDAY INTO SUNDAY NIGHT FOR A CONTINUED CHANCE OF
SHOWERS/THUNDERSTORMS. THIS CONVECTION LOOKS TO BE SUB-SEVERE AT
THIS TIME WITH JUST LIGHTNING AND SOME HEAVY DOWNPOURS BEING THE
MAIN IMPACTS. OTHERWISE...LOOK FOR HIGHS IN THE LOWER TO MIDDLE 80S.
MONDAY HOLDS A LOWER-END CHANCE FOR SOME AIRMASS SHOWERS AND
THUNDERSTORMS AS THERE WILL STILL BE A SLIGHT WEAKNESS IN THE HEAT
RIDGE IN PLACE AS HIGHS TOP OFF WELL INTO THE 80S.
FOR MONDAY NIGHT THROUGH TUESDAY...THE REGION WILL BE IN AN AREA OF
WARM AIR ADVECTION/ISENTROPIC LIFT AHEAD OF LOW PRESSURE CROSSING
THE NORTHERN PLAINS. THIS WILL SPREAD MORE SHOWER/THUNDERSTORM
CHANCES INTO THE AREA. HIGHS ON TUESDAY LOOKS LIKE THEY COULD TOP
90S DEGREES AT SOME LOCATIONS. THEN FOR TUESDAY NIGHT INTO
WEDNESDAY...A COLD FRONT WILL MOVE ACROSS THE AREA FOR A CONTINUED
CHANCE OF SHOWERS AND STORMS.
THURSDAY LOOKS TO BE DRY AS A WEAK RIDGE OF HIGH PRESSURE
ESTABLISHES ITSELF OVER THE REGION. OTHERWISE...PLEASANT WITH HIGHS
IN THE UPPER 7S0 TO THE LOWER 80S.
SMALL-END SHOWER/THUNDER CHANCE RETURN ON FRIDAY AS BOTH THE
GFS/ECMWF SHOW A TROUGH/COLD FRONT MOVING ACROSS MN INTO NORTHWEST
WI. LOOK FOR TEMPERATURES AGAIN IN THE UPPER 70S/LOWER 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1140 PM CDT FRI JUL 24 2015
SOME STORMS HAVE DEVELOPED ALONG A COLD FRONT MAKING ITS WAY
EAST/SOUTHEAST ACROSS THE REGION. THE FRONT HAS ALREADY PAST
KRST...BUT KLSE STILL HAS A CHANCE FOR A THUNDERSTORM TO BRING BRIEF
HEAVY RAIN AND SOME WIND GUSTS THROUGH 07Z OR SO. WITH THE ACTIVITY
LOOKING ISOLATED...WILL CONSIDER A VCTS...OTHERWISE WILL KEEP PCPN
OUT OF FORECAST UNLESS RADAR DICTATES ITS NEEDED.
WINDS GO WEST POST FRONT...AND THEN WILL SHIFT NORTH ON SAT.
EXPECTING VFR CONDITIONS OVERNIGHT THROUGH SAT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
320 AM MDT SAT JUL 25 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 315 AM MDT SAT JUL 25 2015
WATER VAPOR IMAGERY SHOWED A STATIONARY UPPER RIDGE OVER THE
SOUTH CENTRAL CONUS WITH ACTIVE WESTERLY FLOW OVER THE NORTH
CENTRAL CONUS. SUBTROPICAL MOISTURE AND WEAK WAVES CIRCULATING
CLOCKWISE AROUND THE UPPER HIGH AIDED IN SEVERAL CLUSTERS OF
DEEP CONVECTION FROM THE CENTRAL PLAINS INTO THE LOWER/MID MS
VALLEY. A COMPLEX OF TSTORMS DEVELOPED ACROSS NORTHEAST WY
ASSOCIATED WITH THE LEFT FRONT QUADRANT OF UPPER JET STREAK.
THIS COMPLEX WILL CONTINUE TO TRACK EAST-NORTHEAST ACROSS
NORTHWEST SD OVERNIGHT. SURFACE ANALYSIS DEPICTED A WAVY FRONT
FROM A LOW IN NORTH CENTRAL IA ACROSS SOUTHERN NE...NORTHWEST KS
AND EAST CENTRAL CO THEN CURVING NORTHWEST INTO EASTERN WY. BACK
EDGE OF CIRRUS WAS MOVING THROUGH WESTERN NE LEAVING MOSTLY CLEAR
SKIES TO THE WEST.
THE LARGE SCALE PATTERN WE`VE BEEN ACCUSTOMED TO THE PAST SEVERAL
DAYS WILL CONTINUE WITH A CENTRAL CONUS RIDGE FLANKED BY TROUGHS
TO THE WEST AND EAST. ISOLATED CONVECTION DEVELOPED OVER THE
PLAINS LATE FRIDAY ALONG A INSTABILITY GRADIENT. THE GRADIENT
WILL SHIFT EAST OF THE CWA TODAY...HOWEVER JET ENERGY COMBINED
WITH LINGERING MID LEVEL MOISTURE MAY TRIGGER ISOLATED AFTERNOON
CONVECTION ACROSS THE HIGH PLAINS. THE MAJORITY OF THE MODELS
MAINTAIN DRY CONDITIONS...HOWEVER THE HRRR GENERATES A 20-30
PERCENT COVERAGE OF CONVECTION. NOT TOTALLY BUYING THE HRRR...WITH
10-15 PERCENT POPS FORECAST ATTM. 700MB TEMPERATURES PEAK NEAR 15C
TODAY WITH AFTERNOON HIGHS IN THE UPPER 80S-MID 90S FOR THE
PLAINS. IT WILL BE BREEZY WEST OF THE LARAMIE RANGE WITH SOUTHWEST
WINDS GUSTING TO NEAR 25 MPH.
HIGH TEMPERATURES SUNDAY AND MONDAY WILL BE 3-5 DEGREES WARMER
WITH 700MB TEMPERATURES PEAKING 16-17C. 90S WILL PREVAIL EAST
OF THE LARAMIE RANGE BOTH DAYS. MONDAY AFTERNOON WILL BE WARMEST
OF THE TWO DAYS...WITH A FEW LOCATIONS IN THE WESTERN NE PANHANDLE
TOPPING OUT AT 100 DEGREES. LOW LEVEL THERMAL/INSTABILITY AXIS
WILL RESIDE EAST OF THE CWA...HOWEVER WITH THE POSITION OF THE
RIGHT REAR QUADRANT OF THE UPPER JET OVERHEAD...CANNOT RULE OUT
A FEW AFTERNOON/EARLY EVENING TSTORMS FOR THE HIGH PLAINS SUNDAY
AND MONDAY. THE PRESSURE GRADIENT AND INCREASING SOUTHWEST FLOW
ALOFT AHEAD OF AN APPROACHING TROUGH AND COLD FRONT MONDAY WILL
INDUCE WINDY CONDITIONS WEST OF THE LARAMIE RANGE WITH GUSTS
POSSIBLY EXCEEDING 40 MPH.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 230 AM MDT SAT JUL 25 2015
WEATHER CONDITIONS WILL REMAIN ON THE DRIER SIDE THROUGH THE
LONGER TERM FORECAST PERIOD. MONDAY NIGHT STARTS OFF WITH AN
UPPER LEVEL TROUGH OVER THE NORTHERN ROCKIES. DEPENDING ON THE
EXACT TRACK OF THE UPPER LEVEL LOW COULD SEE A FEW THUNDERSTORMS
OVER FAR NORTHERN AND/OR EASTERN PORTIONS OF THE FORECAST AREA
MONDAY EVENING. CURRENTLY THE GFS AND ECMWF KEEP THE MAIN ENERGY
NORTH OF THE FORECAST AREA.
A REINFORCING PUSH OF COOLER AIR EXPECTED TUESDAY AS THE MAIN
UPPER LEVEL TROUGH PUSHES EAST INTO THE PLAINS. TIMING OF THE COOL
PUSH SHOULD KEEP CHANCES FOR PRECIPITATION AT A MINIMUM OVER THE
FORECAST AREA WITH THUNDERSTORM ACTIVITY LIKELY DEVELOPING WELL
EAST INTO CENTRAL NEBRASKA AND SOUTH INTO COLORADO. HIGH
TEMPERATURES TUESDAY SHOULD RANGE FROM THE LOWER 70S WEST TO
LOW-MID 80S INTO THE PLAINS.
MILD TEMPERATURES SHOULD CONTINUE WEDNESDAY WITH SOUTHEAST LOW
LEVEL FLOW IN PLACE OVER THE PLAINS. WEDNESDAY ALSO LOOKS TO BE ON
THE DRY SIDE WITH VERY MINIMAL CHANCES FOR PRECIPITATION...
ESPECIALLY WITH THE FORECAST AREA UNDER THE SUBSIDENCE SIDE OF THE
REAR UPPER LEVEL JET. ALSO LOOKING AT WESTERLY FLOW ALOFT
DEVELOPING WITH ZONAL FLOW IN PLACE OVER THE WESTERN CONUS.
WARMING TREND FOR LATTER PORTIONS OF NEXT WEEK WITH RIDGING OVER
THE WESTERN CONUS AND WEST TO NORTHWEST FLOW OVER THE FORECAST
AREA. HIGH TEMPERATURES SHOULD WARM INTO THE LOW 80S WEST TO
AROUND 90 INTO THE PLAINS THURSDAY AND SLIGHTLY WARMER FRIDAY.
EXPECTING VERY ISOLATED AFTERNOON THUNDERSTORMS ACTIVITY BUT
OVERALL CHANCES FOR WETTING RAIN WILL BE VERY LOW WITH
THUNDERSTORM COVERAGE LIKELY LESS THAN 10 PERCENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 919 PM MDT FRI JUL 24 2015
VFR. THROUGH 12Z...MOSTLY CLEAR SKIES NORTH OF A LARAMIE TO
TORRINGTON LINE...SCATTERED TO BROKEN CLOUDS AT OR ABOVE 10000
FEET AGL SOUTH OF THIS LINE.
AFTER 12Z...SCATTERED TO BROKEN CLOUDS AT OR ABOVE 10000 FEET AGL.
WINDS GUSTING 20 TO 30 KNOTS AFTER DAYBREAK ON SATURDAY...THEN
DECREASING EARLY SATURDAY EVENING.
&&
.FIRE WEATHER...
ISSUED AT 222 AM MDT SAT JUL 25 2015
WARM AND MAINLY DRY CONDITIONS WILL CONTINUE FOR THE DISTRICTS
THROUGH MONDAY BEFORE THE PASSAGE OF A COLD FRONT TUESDAY. NEAR-
CRITICAL WINDS AND HUMIDITIES FOR PORTIONS OF EAST CENTRAL AND
SOUTH CENTRAL WYOMING CAN BE EXPECTED THIS WEEKEND. THE BEST
CHANCE FOR WIDESPREAD CRITICAL FIRE WEATHER CONDITIONS WILL BEGIN
MONDAY MORNING AS WINDS ALOFT INCREASE FOLLOWING POOR OVERNIGHT
HUMIDITY RECOVERIES. SOUTHWEST WINDS MAY GUST OVER 40 MPH WEST OF
THE LARAMIE RANGE MONDAY WITH AFTERNOON HUMIDITIES FALLING INTO
THE SINGLE DIGITS TO LOW TEENS PERCENT. COOLER TEMPERATURES AND
SLIGHTLY HIGHER HUMIDITIES WILL PREVAIL TUESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...MAJ
LONG TERM...SML
AVIATION...SAR
FIRE WEATHER...MAJ
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1139 AM EDT SAT JUL 25 2015
.UPDATE...
A SURFACE COLD JUST PUSHED SOUTH OF JAX INTERNATIONAL AIRPORT
TRAILED BY A WIND SHIFT TO THE NE...GUSTS UP TO 20-25 MPH...AND
SPOTTY SHOWER ACTIVITY PRESSING SSW FROM THE GA COAST. DEEPER
CONVECTION INCLUDING ISOLATED THUNDER WAS ALONG THE SURFACE FRONT
WELL OFFSHORE OVER THE COASTAL WATERS BEYOND 50 NM IN THE VICINITY
OF A BROAD SURFACE LOW. A LOW POST-FRONTAL STRATUS DECK OVER SE GA
WAS LIFTING INTO A BROKEN CUMULUS FIELD...WITH ADDITIONAL CUMULUS
POPPING ACROSS THE EASTERN HALF OF NE FL. TEMPS WERE IN THE
LOW/MID 80S ALREADY WITH LOW/MID 70 DEW PTS.
THE HRRR HAD AN EXCELLENT HANDLE ON MORNING RAINFALL TRENDS AND
ADVERTISED ADDITIONAL BLOSSOMING OF POST-FRONTAL PRECIP ACROSS SE
GA THROUGH AND THE EASTERN HALF OF NE FL THROUGH EARLY AFTN. THE
12Z JAX RAOB SHOWED DRIER AIR BEGINNING TO INFILTRATE THE MID AND
UPPER LEVELS...WHICH WILL HELP LIMIT POST-FRONTAL TSTORM
POTENTIAL. THUS ADVERTISED ISOLATED TSTORMS FOR ALL AREAS TODAY
EXCEPT FOR OUR FL ZONES ALONG AND WEST OF THE HIGHWAY 301 CORRIDOR
WERE MORE SCATTERED TSTORMS ARE LIKELY AND FEW STRONGER CELLS WITH
GUSTY WINDS COULD FORM DURING PEAK HEATING. BRIEF LOCALLY HEAVY
RAINFALL POTENTIAL EXISTS TODAY WITH THE BEST CHANCE OF AMOUNTS
ABOVE A HALF AN INCH ACROSS PORTIONS OF GILCHRIST...ALACHUA...AND
MARION COUNTIES WHERE THE FRONT WILL COMBINED WITH DIURNAL
HEATING...SEA BREEZE CONVERGENCE AND PASSING UPPER LEVEL SHORT
WAVE ENERGY. HIGH TEMPS WILL RANGE FROM THE LOWER 90S ACROSS SE GA
TO THE UPPER 80S ACROSS MUCH OF NE FL WERE MORE CLOUD COVER AND
PRECIP IS EXPECTED. BREEZY ONSHORE WILL KEEP THE COAST COOLER WITH
HIGHS IN THE LOW/MID 80S.
&&
.AVIATION...PREVAILING MVFR TO VFR CONDITIONS EXPECTED ACROSS THE
AREA TODAY UNDER PASSING SHOWERS. ADVERTISED TEMPO TS THIS
AFTERNOON AT GNV ONLY...WITH SHOWERS ELSEWHERE. TONIGHT LOW
STRATUS AND GROUND FOG WILL BE POSSIBLE AT ALL TERMINALS AND WILL
TREND TOWARD MVFR CONDITIONS IN THE 18Z PACKAGE.
&&
.MARINE...COMBINED THE GA WATERS WITH THE FL WATERS N OF ST
AUGUSTINE WHERE NE WINDS WILL NEAR 15-20 KTS TODAY TRAILING THE
COLD FRONT AND ADVERTISED SMALL CRAFT EXERCISE CAUTION. OUR FL
WATERS FROM SGJ-FLAGLER BEACH ARE EXPECTED TO EXPERIENCE LIGHTER E
WINDS AS THE FRONTAL ZONE BEGINS TO STALL ACROSS CENTRAL FL LATER
TODAY INTO SUN AND THU NO HEADLINES EXPECTED...BUT DO EXPECT
BETTER COVERAGE OF SHOWERS AND ISOLATED TSTORMS OVER THAT LEG
THROUGH THE WEEKEND.
RIP CURRENTS: MODERATE RISK OF RIP CURRENTS TODAY.
&&
.HYDROLOGY...BLACK CREEK AT PENNY FARMS REMAINS WELL BEHAVED WITH
THE LATEST STAGE 7.86 FT WELL BELOW 10 FT ACTION STAGE. ELSEWHERE
THE OCKLAWAHA RIVER NEAR OCALA HAS RISEN TO ACTION STAGE WITH
YESTERDAYS RAINFALL. COULD SEE ADDTTIONAL RISES ACROSS THE
SUWANNEE RIVER VALLEY THROUGH EARLY NEXT WEEK WITH MORE RAINFALL
EXPECTED TODAY.
.PRELIMINARY POINT TEMPS/POPS...
AMG 93 70 95 70 / 30 0 10 10
SSI 87 76 86 77 / 50 10 10 10
JAX 89 74 90 72 / 50 20 20 20
SGJ 86 76 87 75 / 50 30 40 20
GNV 90 72 91 73 / 60 20 40 20
OCF 90 72 91 73 / 60 50 60 30
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
ENYEDI/PETERSON/COMBS
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
750 AM CDT SAT JUL 25 2015
...SOUNDING DISCUSSION...
AN ELEVATED TEMPERATURE INVERSION BEGINS AROUND 750 FEET AND GOES
UP TO 2000 FEET. 925 MB TEMPERATURE IS ALMOST 26C WITH THE 850MB
TEMPERATURE AT 19.5C...BOTH OF WHICH ARE RECORDS FOR THIS
DATE/TIME BASED OFF OF SPC SOUNDING CLIMATOLOGY. MOST OF THE
MOISTURE IN THE COLUMN IS BELOW 12000 FEET WITH A NEAR SATURATED
LAYER AROUND 9500 FEET. WHILE ABOVE THIS LAYER THERE IS NOT AS MUCH
MOISTURE...THE PRECIPITABLE WATER IN THE COLUMN IS AT 2.06 INCHES.
THE CONVECTIVE TEMPERATURE IS 94F...BUT GIVEN SUBSIDENCE OVERHEAD
WE SHOULD SEE LIMITED THUNDERSTORMS AGAIN TODAY. LATEST HRRR HAS
PROGGED WELL WITH SHOWERS OVER COASTAL MISSISSIPPI AND
THUNDERSTORMS SOUTH OF PASCAGOULA/MOBILE. IT POPS QUITE A FEW
SHOWERS AND THUNDERSTORMS AROUND MIDDAY. HOWEVER...IT`S COVERAGE
IS LIKELY OVERDONE DUE TO IT`S HIGHER FORECAST TEMPERATURES. WINDS
IN THE PROFILE ARE FROM THE NORTHWEST FROM THE SURFACE TO 17000
FEET...THEN SLOWLY ROTATE AROUND TO THE NORTH AND THEN FINALLY
NORTHEAST IN THE UPPER LEVELS. A PEAK WIND SPEED OF 28 KNOTS WAS
FOUND NEAR 1000 FEET.
12Z BALLOON INFO: THERE WERE NO ISSUES WITH THE FLIGHT THIS
MORNING. THE BALLOON REACHED A HEIGHT OF 19.6 MILES ABOVE THE
GROUND BURSTING OVER THE SOUTHWEST PART OF LAKE PONTCHARTRAIN 34
MILES DOWNRANGE FROM THE OFFICE. THE BALLOON ASCENDED FOR 100
MINUTES.
ANSORGE
&&
.PREV DISCUSSION... /ISSUED 351 AM CDT SAT JUL 25 2015/
DISCUSSION...
THE STRONG UPPER RIDGE CENTERED OVER THE SOUTHERN PLAINS THIS
MORNING WILL CONTINUE TO DOMINATE THE WEATHER ACROSS THE FORECAST
AREA FOR MUCH OF THE FORECAST PERIOD. THIS WILL MEAN THE CONTINUATION
OF HOT AND HUMID CONDITIONS WITH LIMITED CHANCES FOR CONVECTION
FOR SEVERAL MORE DAYS. THE CENTRAL GULF COAST REGION WILL BE ON
THE PERIPHERY OF THIS RIDGE THROUGH WEEKEND WITH A WEAKNESS ALOFT
SITUATED OVER NORTH FLORIDA AND THE SOUTHEAST. IMPULSES ROTATING
THE RIDGE MAY RESULT IN THE DEVELOPMENT OF SCATTERED CONVECTION...
BUT PRIMARILY ACROSS THE EASTERN THIRD OF THE FORECAST AREA. A
WEAK BACKDOOR COLD FRONT SITUATED TO THE NORTHEAST OF THE FORECAST
AREA OVER THE SOUTHEAST CONUS WILL ALSO SERVE AS A FOCUS FOR
CONVECTION. THIS BOUNDARY WILL REMAIN JUST TO THE EAST OF THE AREA
BEFORE WASHING OUT...BUT MAY BE CLOSE ENOUGH TO AID CONVECTION
CHANCES ACROSS SOUTH MISSISSIPPI. RAIN CHANCES WILL LIKELY
DECREASE AGAIN FOR THE FIRST HALF OF THE WORK WEEK AS THE
INFLUENCE OF THE UPPER RIDGE INCREASES ACROSS THE AREA AS IT
SHIFTS BACK TO THE EAST NORTHEAST AND BECOMES CENTERED OVER THE
OZARKS REGION. THE BEST CHANCES FOR ANY CONVECTION DURING THIS
PERIOD WILL REMAIN ACROSS THE COASTAL AREAS. MODELS DO INDICATE A
PATTERN CHANGE FOR THE END OF THE WEEK AND INTO NEXT WEEKEND AS
THE UPPER RIDGE RETROGRADES TO THE FOUR CORNERS REGION AS AN
UPPER TROUGH DEEPENS OVER THE EASTERN CONUS. THIS WILL ALLOW FOR A
COLD FRONT TO PUSH DEEP INTO THE SOUTH. THIS WILL RESULT IN HIGHER
RAIN CHANCES FOR THE AREA AS WELL AS SOME RELIEF IN THE
TEMPERATURE DEPARTMENT. IN THE MEANTIME HOWEVER...HIGHS MAINLY IN
THE MID 90S AND DEW POINTS IN THE 70S WILL PRODUCE HEAT INDICES PRIMARILY
IN THE 102 TO 108 DEGREE RANGE..JUST BELOW ADVISORY CRITERIA. 11
AVIATION...
CONVECTION THAT MOVED NEAR KGPT SEVERAL HOURS AGO IS WELL OUT INTO
THE GULF OF MEXICO. A NARROW BAND OF SHOWERS AND THUNDERSTORMS HAS
REDEVELOPED FROM NORTH OF KJAN TO KMOB. AT THIS POINT...IF THERE IS
A THREAT TO ANY LOCAL TERMINALS OVER THE NEXT SEVERAL HOURS...IT
WOULD LIKELY BE LIMITED TO KGPT. EXPECT GENERAL VFR CONDITIONS
THROUGH THE FORECAST PERIOD. WILL CARRY MENTION OF VCTS FOR
TERMINALS ACROSS THE SE HALF OF THE AREA INCLUDING KGPT...KASD...
KNEW...KMSY AND KHUM DURING THE AFTERNOON HOURS TODAY. ANY
THUNDERSTORMS AFFECTING A TERMINAL LIKELY TO PRODUCE MVFR CONDITIONS
FOR LESS THAN ONE HOUR. 35
MARINE...
THE WEAK NOCTURNAL COASTAL JET OVER THE NEARSHORE GULF COASTAL
WATERS EAST OF THE CHANDELEUR SOUND AND SOUTH OF THE MISSISSIPPI
SOUND APPEARS TO WEAKEN ONCE WE GET PAST THIS MORNING. FOR MUCH OF
THE REMAINDER OF THE FORECAST PERIOD...WINDS GENERALLY REMAIN 10
KNOTS OR BELOW WITH SEAS LIMITED TO 1 TO 2 FEET. 35
DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER FROM RED
RIVER LANDING TO DONALDSONVILLE.
POTENTIAL SPOT FORECAST FOR IRISH BAYOU MARSH FIRE.
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 96 76 95 76 / 20 10 20 10
BTR 96 77 96 77 / 20 10 20 10
ASD 96 78 95 77 / 30 20 20 10
MSY 96 79 96 79 / 30 20 30 10
GPT 95 79 95 78 / 40 30 20 10
PQL 95 77 95 76 / 40 30 20 10
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1137 AM EDT SAT JUL 25 2015
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 330 AM EDT SAT JUL 25 2015
IT WILL FEEL LIKE THE DOG DAYS OF SUMMER AS WE HEAD THROUGH THE REST
OF THE WEEKEND AND INTO THE MIDDLE PART OF THE WORK WEEK. HIGHS WILL
LIKELY TOP OUT IN THE MIDDLE 80S TODAY WITH UPPER 80S IN MANY AREAS
FOR SUNDAY AND MONDAY. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE
NEXT WEEK AS WE WILL LIKELY PUSH TO OR EXCEED 90 DEGREES. A
WEAKENING COLD FRONT IS EXPECTED TO SLIDE THROUGH SOUTHWEST LOWER
MICHIGAN TODAY AND BRING WITH IT SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WIDESPREAD PRECIPITATION IS NOT EXPECTED...IN FACT MANY
AREAS WILL REMAIN DRY. FAIR AND DRY WEATHER IS ON TAP FOR SUNDAY
INTO EARLY NEXT WEEK AS HIGH PRESSURE WILL BE SITUATED OVER THE
AREA.
&&
.UPDATE...
ISSUED AT 1101 AM EDT SAT JUL 25 2015
TRIMMED POPS CONSIDERABLY THIS AFTERNOON FOR THE WESTERN TWO
THIRDS OF THE FORECAST AREA. THIS IS BASED LARGELY ON THE LAST
SEVERAL RUNS OF THE HRRR. SURFACE OBSERVATIONS SHOW A CONSIDERABLE
SHIFT TO WESTERLY FLOW AT THE LAKESHORE...HERALDING THE APPROACH
OF THE STABLE MARINE LAYER OFF LAKE MICHIGAN. THIS AND
CONSIDERABLE CLOUDINESS OVER LOWER MICHIGAN SHOULD LIMIT
DESTABILIZATION OVER MOST OF SOUTHWEST LOWER MICHIGAN. CLOUDINESS
SHOULD GRADUALLY ERODE FROM WEST TO EAST. COLD FRONT CURRENTLY
EXTENDING FROM FAR NORTHERN LAKE MICHIGAN THROUGH MADISON
WISCONSIN WILL PROVIDE A FOCUS FOR DEEPER CONVECTION...MAINLY OVER
SOUTH-CENTRAL AND SOUTHEAST LOWER MICHIGAN. THE OVERALL SEVERE
THREAT REMAINS LIMITED. PLEASE SEE THE SPC DAY1 OUTLOOK FOR
FURTHER DETAILS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
CONCERNS IN THE SHORT TERM ARE RELATED TO SHOWER AND STORM CHANCES
TODAY AND THEN TWEAKING HIGH TEMPERATURES THE NEXT COUPLE DAYS AS WE
WILL BE QUITE WARM.
AS FOR CONVECTION TODAY...IT LOOKS LESS AND LESS IMPRESSIVE WITH
EACH MODEL RUN. THE HRRR GUIDANCE IS ONLY SHOWING SCATTERED STORMS
AT BEST. THE LATEST RAP GUIDANCE IS INDICATING MOST UNSTABLE CAPE
VALUES OF 1000-2000 J/KG WHICH IS MORE THAN ENOUGH...BUT OTHER
FACTORS LIMIT THE THREAT. THEY ARE NAMELY...THE MAIN SHORTWAVE IS
WELL NORTH OF THE AREA AND A WIND OFF THE LAKE WILL LIKELY TEMPER
INSTABILITY DURING THE AFTERNOON. MID LEVEL LAPSE RATES ARE NOT
STEEP EITHER...ON THE ORDER OF 5.5 C/KM. THE LLJ AND 850MB MOISTURE
TRANSPORT HAVE TRENDED DOWN AS WELL. BOTTOM LINE...LOOKING FOR
SCATTERED STORMS TO DEVELOP MIDDAY AND WORK SOUTH/EAST OUT OF THE
AREA DURING THE AFTERNOON HOURS. ANY CHANCE OF A STRONG STORM WOULD
BE DURING THE AFTERNOON TOWARDS LAN/BTL/JXN.
OTHERWISE FAIR WEATHER IS EXPECTED WITH HIGH PRESSURE BUILDING IN
BEHIND THE WEAKENING COLD FRONT. AFTER TODAY WITH CLOUDS ASSOCIATED
WITH THE FRONT...SKIES SHOULD BE MAINLY CLEAR. THINKING WE WILL PUSH
INTO THE MID 80S TODAY...CLOUD COVER IS A BIT OF A CONCERN WHICH
COULD TREND THINGS EITHER SIDE OF THOSE NUMBERS. UPPER 80S LOOK
PRETTY SOLID FOR SUNDAY AND MONDAY GIVEN 850MB TEMPS IN THE 17-19C
RANGE.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
OUR MAIN FOCUS OF THE LONG TERM IS THE FRONTAL PASSAGE THAT IS
EXPECTED DURING THE MID-WEEK TIME FRAME...AND THE CHCS OF CONVECTION
THAT WILL ACCOMPANY THE FRONT.
THE BEGINNING OF THE PERIOD IS EXPECTED TO BE HOT AND HUMID WITH
LITTLE CHCS OF RAIN INITIALLY. WE WILL HAVE A FAIRLY DECENT UPPER
RIDGE IN PLACE. THIS UPPER RIDGE WITH HIGH HEIGHTS WILL SUPPORT THE
HOT WEATHER AND WILL CAP THE ATMOSPHERE OFF FROM ANY PCPN FROM
OCCURRING. WE ARE LOOKING AT A GOOD CHANCE OF LOWER 90S ON TUE WITH
H850 TEMPS APPROACHING 20C.
THERE IS A LITTLE UNCERTAINTY WITH THE SPECIFIC TIMING OF THE
SHOWERS/STORMS WITH THE FRONT MID-WEEK. THE CONSENSUS OF THE CHC OF
SHOWERS/STORMS LOOKS TO OCCUR TUE NIGHT INTO WED. SOME MODELS ARE A
LITTLE EARLIER...AND SOME ARE A LITTLE LATER. IT DOES NOT LOOK LIKE
A STRONG FEED OF GULF MOISTURE WILL BE PRESENT. ENOUGH SHOULD BE
AROUND WITH THE STRENGTH OF THE FRONT TO BRING A DECENT CHC OF RAIN.
SEVERE CHCS ARE NOT LOOKING REAL STRONG AT THIS POINT. THERE DOES
LOOK TO BE A GOOD DEAL OF INSTABILITY PRESENT...ESPECIALLY DURING
PEAK HEATING ON WED. DEEP LAYER SHEAR IS LACKING A BIT WITH THE
BETTER WIND FIELDS LAGGING THE FRONT/STORMS A BIT. WE WILL CONTINUE
TO MONITOR THIS POTENTIAL AND THE TRENDS OVER THE NEXT FEW DAYS.
WE WILL SEE A COOL DOWN ALONG WITH DRIER CONDITIONS FOR THE THU AND
FRI TIME FRAME. WE WILL SEE A TROUGH OVER THE AREA EVENTUALLY GIVING
WAY TO A SFC RIDGE. NW FLOW ALOFT AND IN THE LOWER LEVELS WILL COOL
US OFF A BIT. IT DOES NOT LOOK TOO COLD AT THIS TIME WITH H850 TEMPS
DROPPING INTO THE LOWER TEENS C.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 753 AM EDT SAT JUL 25 2015
CUMULUS CLOUDS ARE EXPECTED TO FILL IN THIS MORNING...TAKING
CONDITIONS BROKEN AT ALL TAF SITES. CEILINGS FOR THE MOST PART
WILL BE IN THE 3500-5000FT RANGE...BUT FOR A TIME FROM
15Z-18Z...KMKG AND KGRR WILL LIKELY GO MVFR WITH CEILINGS JUST
BELOW OR NEAR 3000FT.
A WEAK COLD FRONT WILL BE SLIDING SOUTH THROUGH THE AREA TODAY AND
SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT CAN BE EXPECTED. AT
THIS POINT COVERAGE LOOKS TO BE SOMEWHAT SPARSE AND THEREFORE ONLY
HAVE VCSH WORDING IN THE TAFS.
SKIES WILL CLEAR OUT THIS EVENING AND REMAIN THAT WAY OVERNIGHT.
THERE MAY BE SOME LIGHT FOG LATE TONIGHT...BUT DECIDED TO HOLD OFF
ADDING ANOTHER FORECAST GROUP INTO THE 12Z TAFS.
&&
.MARINE...
ISSUED AT 330 AM EDT SAT JUL 25 2015
WAVES OF 1 TO 3 FEET ARE EXPECTED THIS MORNING FROM GRAND HAVEN
NORTHWARD IN A ZONE WHERE SOUTHWEST WINDS OF 10 TO 20 KNOTS WILL
BUILD WAVE HEIGHTS. WINDS LOOK A BIT DOWN FROM WHAT WE WERE SEEING
IN THE MODELS THE LAST COUPLE NIGHTS...SO THE MORE WIDESPREAD 2 TO 4
FOOT WAVES LOOK LESS LIKELY.
AFTER THIS MORNING...QUIET WEATHER OUT ON THE BIG LAKE THE REST OF
THE WEEKEND WITH HIGH PRESSURE IN PLACE. WAVES OF 2 FEET OR LESS AND
WINDS LESS THAN 15 KNOTS SHOULD BE COMMON PLACE.
&&
.HYDROLOGY...
ISSUED AT 1137 AM EDT SAT JUL 25 2015
NO FLOODING CONCERNS EXIST THROUGH THE NEXT SEVERAL DAYS.
RECENT DRY CONDTIONS AND LITTLE EXPECTED RAINFALL HAS RESULTED IN
FALLING RIVER LEVELS. A FEW SCATTERED STORMS ARE EXPECTED TODAY
WITH VERY LOCALIZED HEAVY RAINFALL POSSIBLE. HOWEVER...THIS MAY BE
BRIEF WITH THE LACK OF ANY WIDESPREAD MOISTURE.
ALL RIVERS ARE WELL WITHIN BANKS AND THE STEADY OR FALLING TREND
WILL LIKELY CONTINUE THROUGH THE NEXT FEW DAYS. WARM AND HUMID
CONDITIONS WILL LACK MUCH IN THE WAY OF RAINFALL. A MID WEEK COLD
FRONT WILL HELP TO INCREASE RAIN CHANCES...BUT EVEN THESE TOTALS
SHOULD WILL BE RELATIVELY LIGHT IN REGARDS TO ANY HIGHLIGHTING AND
HYDRO ISSUES.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...TJT
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...NJJ
AVIATION...DUKE
HYDROLOGY...JAM
MARINE...DUKE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1115 AM EDT SAT JUL 25 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 330 AM EDT SAT JUL 25 2015
IT WILL FEEL LIKE THE DOG DAYS OF SUMMER AS WE HEAD THROUGH THE REST
OF THE WEEKEND AND INTO THE MIDDLE PART OF THE WORK WEEK. HIGHS WILL
LIKELY TOP OUT IN THE MIDDLE 80S TODAY WITH UPPER 80S IN MANY AREAS
FOR SUNDAY AND MONDAY. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE
NEXT WEEK AS WE WILL LIKELY PUSH TO OR EXCEED 90 DEGREES. A
WEAKENING COLD FRONT IS EXPECTED TO SLIDE THROUGH SOUTHWEST LOWER
MICHIGAN TODAY AND BRING WITH IT SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WIDESPREAD PRECIPITATION IS NOT EXPECTED...IN FACT MANY
AREAS WILL REMAIN DRY. FAIR AND DRY WEATHER IS ON TAP FOR SUNDAY
INTO EARLY NEXT WEEK AS HIGH PRESSURE WILL BE SITUATED OVER THE
AREA.
&&
.UPDATE...
ISSUED AT 1101 AM EDT SAT JUL 25 2015
TRIMMED POPS CONSIDERABLY THIS AFTERNOON FOR THE WESTERN TWO
THIRDS OF THE FORECAST AREA. THIS IS BASED LARGELY ON THE LAST
SEVERAL RUNS OF THE HRRR. SURFACE OBSERVATIONS SHOW A CONSIDERABLE
SHIFT TO WESTERLY FLOW AT THE LAKESHORE...HERALDING THE APPROACH
OF THE STABLE MARINE LAYER OFF LAKE MICHIGAN. THIS AND
CONSIDERABLE CLOUDINESS OVER LOWER MICHIGAN SHOULD LIMIT
DESTABILIZATION OVER MOST OF SOUTHWEST LOWER MICHIGAN. CLOUDINESS
SHOULD GRADUALLY ERODE FROM WEST TO EAST. COLD FRONT CURRENTLY
EXTENDING FROM FAR NORTHERN LAKE MICHIGAN THROUGH MADISON
WISCONSIN WILL PROVIDE A FOCUS FOR DEEPER CONVECTION...MAINLY OVER
SOUTH-CENTRAL AND SOUTHEAST LOWER MICHIGAN. THE OVERALL SEVERE
THREAT REMAINS LIMITED. PLEASE SEE THE SPC DAY1 OUTLOOK FOR
FURTHER DETAILS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
CONCERNS IN THE SHORT TERM ARE RELATED TO SHOWER AND STORM CHANCES
TODAY AND THEN TWEAKING HIGH TEMPERATURES THE NEXT COUPLE DAYS AS WE
WILL BE QUITE WARM.
AS FOR CONVECTION TODAY...IT LOOKS LESS AND LESS IMPRESSIVE WITH
EACH MODEL RUN. THE HRRR GUIDANCE IS ONLY SHOWING SCATTERED STORMS
AT BEST. THE LATEST RAP GUIDANCE IS INDICATING MOST UNSTABLE CAPE
VALUES OF 1000-2000 J/KG WHICH IS MORE THAN ENOUGH...BUT OTHER
FACTORS LIMIT THE THREAT. THEY ARE NAMELY...THE MAIN SHORTWAVE IS
WELL NORTH OF THE AREA AND A WIND OFF THE LAKE WILL LIKELY TEMPER
INSTABILITY DURING THE AFTERNOON. MID LEVEL LAPSE RATES ARE NOT
STEEP EITHER...ON THE ORDER OF 5.5 C/KM. THE LLJ AND 850MB MOISTURE
TRANSPORT HAVE TRENDED DOWN AS WELL. BOTTOM LINE...LOOKING FOR
SCATTERED STORMS TO DEVELOP MIDDAY AND WORK SOUTH/EAST OUT OF THE
AREA DURING THE AFTERNOON HOURS. ANY CHANCE OF A STRONG STORM WOULD
BE DURING THE AFTERNOON TOWARDS LAN/BTL/JXN.
OTHERWISE FAIR WEATHER IS EXPECTED WITH HIGH PRESSURE BUILDING IN
BEHIND THE WEAKENING COLD FRONT. AFTER TODAY WITH CLOUDS ASSOCIATED
WITH THE FRONT...SKIES SHOULD BE MAINLY CLEAR. THINKING WE WILL PUSH
INTO THE MID 80S TODAY...CLOUD COVER IS A BIT OF A CONCERN WHICH
COULD TREND THINGS EITHER SIDE OF THOSE NUMBERS. UPPER 80S LOOK
PRETTY SOLID FOR SUNDAY AND MONDAY GIVEN 850MB TEMPS IN THE 17-19C
RANGE.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
OUR MAIN FOCUS OF THE LONG TERM IS THE FRONTAL PASSAGE THAT IS
EXPECTED DURING THE MID-WEEK TIME FRAME...AND THE CHCS OF CONVECTION
THAT WILL ACCOMPANY THE FRONT.
THE BEGINNING OF THE PERIOD IS EXPECTED TO BE HOT AND HUMID WITH
LITTLE CHCS OF RAIN INITIALLY. WE WILL HAVE A FAIRLY DECENT UPPER
RIDGE IN PLACE. THIS UPPER RIDGE WITH HIGH HEIGHTS WILL SUPPORT THE
HOT WEATHER AND WILL CAP THE ATMOSPHERE OFF FROM ANY PCPN FROM
OCCURRING. WE ARE LOOKING AT A GOOD CHANCE OF LOWER 90S ON TUE WITH
H850 TEMPS APPROACHING 20C.
THERE IS A LITTLE UNCERTAINTY WITH THE SPECIFIC TIMING OF THE
SHOWERS/STORMS WITH THE FRONT MID-WEEK. THE CONSENSUS OF THE CHC OF
SHOWERS/STORMS LOOKS TO OCCUR TUE NIGHT INTO WED. SOME MODELS ARE A
LITTLE EARLIER...AND SOME ARE A LITTLE LATER. IT DOES NOT LOOK LIKE
A STRONG FEED OF GULF MOISTURE WILL BE PRESENT. ENOUGH SHOULD BE
AROUND WITH THE STRENGTH OF THE FRONT TO BRING A DECENT CHC OF RAIN.
SEVERE CHCS ARE NOT LOOKING REAL STRONG AT THIS POINT. THERE DOES
LOOK TO BE A GOOD DEAL OF INSTABILITY PRESENT...ESPECIALLY DURING
PEAK HEATING ON WED. DEEP LAYER SHEAR IS LACKING A BIT WITH THE
BETTER WIND FIELDS LAGGING THE FRONT/STORMS A BIT. WE WILL CONTINUE
TO MONITOR THIS POTENTIAL AND THE TRENDS OVER THE NEXT FEW DAYS.
WE WILL SEE A COOL DOWN ALONG WITH DRIER CONDITIONS FOR THE THU AND
FRI TIME FRAME. WE WILL SEE A TROUGH OVER THE AREA EVENTUALLY GIVING
WAY TO A SFC RIDGE. NW FLOW ALOFT AND IN THE LOWER LEVELS WILL COOL
US OFF A BIT. IT DOES NOT LOOK TOO COLD AT THIS TIME WITH H850 TEMPS
DROPPING INTO THE LOWER TEENS C.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 753 AM EDT SAT JUL 25 2015
CUMULUS CLOUDS ARE EXPECTED TO FILL IN THIS MORNING...TAKING
CONDITIONS BROKEN AT ALL TAF SITES. CEILINGS FOR THE MOST PART
WILL BE IN THE 3500-5000FT RANGE...BUT FOR A TIME FROM
15Z-18Z...KMKG AND KGRR WILL LIKELY GO MVFR WITH CEILINGS JUST
BELOW OR NEAR 3000FT.
A WEAK COLD FRONT WILL BE SLIDING SOUTH THROUGH THE AREA TODAY AND
SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT CAN BE EXPECTED. AT
THIS POINT COVERAGE LOOKS TO BE SOMEWHAT SPARSE AND THEREFORE ONLY
HAVE VCSH WORDING IN THE TAFS.
SKIES WILL CLEAR OUT THIS EVENING AND REMAIN THAT WAY OVERNIGHT.
THERE MAY BE SOME LIGHT FOG LATE TONIGHT...BUT DECIDED TO HOLD OFF
ADDING ANOTHER FORECAST GROUP INTO THE 12Z TAFS.
&&
.MARINE...
ISSUED AT 330 AM EDT SAT JUL 25 2015
WAVES OF 1 TO 3 FEET ARE EXPECTED THIS MORNING FROM GRAND HAVEN
NORTHWARD IN A ZONE WHERE SOUTHWEST WINDS OF 10 TO 20 KNOTS WILL
BUILD WAVE HEIGHTS. WINDS LOOK A BIT DOWN FROM WHAT WE WERE SEEING
IN THE MODELS THE LAST COUPLE NIGHTS...SO THE MORE WIDESPREAD 2 TO 4
FOOT WAVES LOOK LESS LIKELY.
AFTER THIS MORNING...QUIET WEATHER OUT ON THE BIG LAKE THE REST OF
THE WEEKEND WITH HIGH PRESSURE IN PLACE. WAVES OF 2 FEET OR LESS AND
WINDS LESS THAN 15 KNOTS SHOULD BE COMMON PLACE.
&&
.HYDROLOGY...
ISSUED AT 1156 AM EDT FRI JUL 24 2015
RIVER LEVELS ARE FALLING AND ARE WELL BELOW BANKFULL. WITH UNDER
AN INCH OF PRECIPITATION EXPECTED THROUGH THE WEEK... THESE
CONDITIONS SHOULD CONTINUE. LOCALLY HEAVY RAINFALL COULD LEAD TO
PONDING OF WATER... MAINLY SATURDAY OR WEDNESDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...TJT
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...NJJ
AVIATION...DUKE
HYDROLOGY...63
MARINE...DUKE
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1033 AM EDT SAT JUL 25 2015
.UPDATE...
CURRENT FORECAST ON TRACK FOR SATURDAY AFTERNOON AND EVENING. 12Z
SOUNDING FOR DTX SUGGESTS ABOUT 1000 K/KG OF ML CAPE WITHOUT ANY
ADDITIONAL MOISTURE ADVECTION IN THE MIXED LAYER. THERE IS SOME
POOLING OF THAT MOISTURE ALONG THE FRONT GIVEN THE DEW POINTS IN
THE UPPER 60S TO AROUND 70 FOR EXTREME SE WI AND NRN IL. STILL
SOME QUESTION IF WE GET ALL OF THAT LOW LEVEL MOISTURE TO REALIZE
2000 J/KG OF ML CAPE...BUT THERE SHOULD BE ENOUGH OF AN INCREASE
TO GET IN THE 1500 J/KG NEIGHBORHOOD. WIND FIELDS MAY BE STRONGEST
THIS MORNING AND ACTUALLY WEAKEN THROUGH THE AFTERNOON. STILL MAY
BE ENOUGH FOR SOME ORGANIZATION OF THE CONVECTION AND MAYBE ONE OR
TWO STORMS TO GET CLOSE TO SEVERE LIMITS. 00Z HI RES RUNS ALL
WERE BULLISH ON MORNING CONVECTION ACROSS NRN AND WC LOWER WHICH
WOULD HAVE IMPACTS ON ITS DEPICTION OF CONVECTION FOR SE LOWER.
THE LATER HRRR AND RAP/RUC CYCLES ARE A LITTLE BETTER AND CONTINUE
THE IDEA OF 16-20Z TIMING FOR THE TRI CITIES...18-22Z FOR THUMB TO
ARB AND 20-00Z FOR METRO DETROIT.
CLOUDS WERE QUITE VARIABLE ACROSS LOWER MICHIGAN. EXPECT THAT TO
CONTINUE AS THE LOWER SC LIFTS INTO A CU FIELD WHILE AREAS OF AC
CONTINUE TO MOVE ACROSS THE REGION. END RESULT SHOULD BE ENOUGH
SUN TO REACH FORECAST HIGHS WHILE THERE WILL NOT BE TOO MUCH SUN
TO GO ANY HIGHER.
&&
.AVIATION...ISSUED 603 AM EDT SAT JUL 25 2015
A COLD FRONT WILL SWEEP THROUGH THE REGION TODAY...AROUND 16Z FOR
MBS AND 21Z FOR DTW...BRINGING A WINDOW OF LOWER CIGS AND POSSIBLE
TSTORMS. VFR CONDITIONS WILL PREVAIL BOTH BEFORE AND AFTER THIS
NARROW WINDOW OF THE FRONTAL PASSAGE IN WHICH MVFR CIGS/VSBYS MAY
OCCUR. CONFIDENCE IS LOW WITH COVERAGE OF POTENTIAL TSTORMS AS
SIGNALS ARE POINTING TO ISOLATED/SCATTERED COVERAGE. WILL INCLUDE A
BRIEF 2 HOUR TEMPO TO ACCOUNT FOR THIS NARROW WINDOW OF POTENTIAL
FOR PTK SOUTHWARD WITH JUST SHOWERS FOR FNT/MBS DUE TO EARLIER
TIMING AND LESS INSTABILITY. NORTHERLY WINDS BEHIND THE FRONT WILL
BRING DRIER AIR BACK TO THE AREA ERODING THE CLOUDS THIS EVENING
INTO THE OVERNIGHT FROM NORTH TO SOUTH. WINDS WILL BRIEFLY INCREASE
FROM THE SW AHEAD OF THE FRONT BUT WILL RELAX SOME OVERNIGHT AS
WIND SWITCH TO NORTHERLY WITH THE NEXT HIGH SETTLING IN.
FOR DTW...COLD FRONT LOOKS TO BE MOVING THROUGH DURING PEAK HEATING
OF SATURDAY...WARRANTING THE TEMPO FOR TSTORMS FROM 20-22Z. UPSTREAM
OBS AND FORECAST SOUNDINGS SUGGEST CIGS WILL HOVER NEAR THE VFR/MVFR
THRESHOLD BUT THINKING IS VFR WILL DOMINATE WITH MVFR BEING MORE
SCATTERED SO WILL FAVOR VFR WITH THE TAFS.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM FOR CIGS AOB 5KFT SATURDAY AFTERNOON AND EVENING.
* LOW FOR THUNDERSTORMS SATURDAY AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 356 AM EDT SAT JUL 25 2015
SHORT TERM...TODAY AND TONIGHT
A WEAKENING COLD FRONT WILL PASS THROUGH LOWER MI TODAY BRINGING THE
CHANCE OF SHOWERS AND THUNDERSTORMS. THE PARENT LOW FOR THE FRONT IS
LOCATED OVER NORTHERN ONTARIO AND WILL CONTINUE SLOWLY EASTWARD
THROUGH THE DAY WHILE THE FRONT PIVOTS AROUND IT AND THROUGH THE
AREA. THE TIMING OF THE FRONT PASSAGE WILL BE IN THE AFTERNOON
AROUND 18-00Z...DURING PEAK HEATING. THIS WILL OF COURSE FAVOR STORM
DEVELOPMENT AS SFC TEMPS REACH INTO THE LOW/MID 80S WITH DEWPOINTS
LOOKING TO REACH 70. WILL CONTINUE WITH CHANCE POPS FOR SHOWERS AND
THUNDERSTORMS TODAY WITH THE MAIN ADJUSTMENT COMING IN THE TIMING OF
THE PRECIP...ELIMINATING ALL POPS BEFORE 14Z AS THE LINE OF
CONVECTION IS STILL FAR TO THE WEST OVER CENTRAL WI. DETAILS OF THE
SETUP TO FOLLOW...
THE UPPER LEVEL JET MAX HAS WORKED ITS WAY ACROSS THE MS RIVER AND
WILL REACH MID MI THIS MORNING. MODELS ALL SHOW THIS TO WEAKEN
THROUGH THE DAY FROM 100 KNOTS DOWN TO AROUND 70 KNOTS. THIS WILL
ALLOW DECENT SHEAR AHEAD OF THE FRONT WITH 0-3KM VALUES AROUND 25-30
KNOTS WHICH WILL BE ENOUGH TO TRY TO ORGANIZE SOME STORMS THAT CAN
DEVELOP. THIS WILL HELP COMPENSATE SOMEWHAT FOR THE LACK OF NOTABLE
FRONTAL FORCING ANYWHERE ALONG THE FRONT. AS HAS BEEN THE CASE MUCH
OF THE CONVECTIVE SEASON...MID LEVEL LAPSE RATES LOOK TO BE VERY
WEAK ONCE AGAIN BUT LL LAPSE RATES WILL BE PRETTY GOOD AS SFC TEMPS
QUICKLY RISE INTO THE MID 80S ONCE AGAIN. CAPE WILL ALSO BE
FAVORABLE AS A CORRIDOR OF 70 DEGREE DEWPOINTS AHEAD OF THE FRONT
SLIDES THROUGH THE AREA. A FAIR VALUE LOOKS TO BE AROUND 1500-2000
J/KG AVAILABLE THIS AFTERNOON. BEST CHANCES FOR ORGANIZED...POSSIBLE
STRONG TO SEVERE...STORMS WILL BE OVER THE SOUTHERN AND EASTERN
LOCATIONS AS THEY WILL HAVE SEVERAL ADDITIONAL HOURS OF HEATING TO
WORK WITH. IN ADDITION THERE APPEARS TO BE A SECONDARY COLD FRONT OR
SHORTWAVE SLIDING IN THIS AFTERNOON WHICH MAY PROVIDE A LITTLE EXTRA
BOOST LATER IN THE DAY. FOR ANY ONE LOCATION THERE LOOKS TO BE
AROUND A 3-5 HOUR WINDOW WHERE THESE ISOLATED TO SCATTERED STORMS
COULD IMPACT THEM. MBS WILL START EARLY IN THE DAY AS THE FRONT
APPROACHES AROUND 14Z...WHICH WILL LIMIT STRENGTH OF THESE
STORMS...WITH DTW HOLD OFF TIL CLOSER TO 18-20Z FOR A START TIME.
ALL ACTIVITY LOOKS TO PASS TO THE SOUTH/EAST BY 00Z. ANY ORGANIZED
STORM WILL HAVE THE POTENTIAL TO PRODUCE 60 MPH GUSTS AND/OR LARGE
HAIL. SPC HAS SOUTHEAST LOWER MI INCLUDED IN THE MARGINAL RISK AREA
WHICH SEEMS REASONABLE FOR THE SETUP.
ONCE THE FRONT PASSES...HIGH PRESSURE WILL CLEAR OUT THE CLOUDS FOR
THE OVERNIGHT BUT TEMPS WILL REMAIN ELEVATED AS THE POST FRONTAL
AIRMASS IS SPORTING DEWPOINTS IN THE LOW 60S.
LONG TERM... SUNDAY THROUGH FRIDAY
A TEMPORARY DIP IN THE UPPER HEIGHT FIELD OVER THE NEXT 24 HOURS
WILL HELP EASE THE ATTENDANT WEAK FRONT INTO THE OHIO VALLEY BY
EARLY SUNDAY. POST-FRONTAL ENVIRONMENT SUNDAY WILL BE MORE NOTABLE
FOR A REDUCTION IN HUMIDITY RELATIVE TO TODAY...WITH NO REAL CHANGE
EXPECTED IN THE TEMPERATURES. THE DRIER AND MORE STABLE CONDITIONS
AS HIGH PRESSURE SLIDES THROUGH WILL TRANSLATE INTO A HIGH DEGREE OF
SUNSHINE. THIS INSOLATION POTENTIAL INTO A DRIER AND MODESTLY MIXED
PROFILE FAVORS A GREATER DIURNAL TEMPERATURE RESPONSE...AND WILL
NUDGE HIGHS UP A COUPLE DEGREE ACCORDINGLY FOR SUNDAY AFTERNOON.
GOING FORECAST HOLDING FIRM WITH EXPECTATIONS THAT CONVECTIVE
ACTIVITY THAT EMERGES ALONG THE FRONTAL ZONE WILL REMAIN SOUTH OF
THE BORDER SUNDAY AND SUNDAY NIGHT.
PREDOMINANT SOUTHERN CONUS UPPER RIDGING WILL UNDERGO STEADY
AMPLIFICATION INTO THE GREAT LAKES THROUGH THE EARLY WEEK PERIOD.
THE ACCOMPANYING RISE IN MEAN THICKNESSES THROUGHOUT THE COLUMN WILL
TRANSLATE INTO SEVERAL DAYS OF ABOVE NORMAL WARMTH. WARMEST
CONDITIONS CENTERED ON THE TUESDAY AND WEDNESDAY PERIODS AS THE
UPPER RIDGE AXIS PIVOTS OVERHEAD...850 MB TEMPERATURES REACHING INTO
THE 18 TO 20C RANGE DURING THIS TIME. THIS WILL SUPPORT READINGS IN
THE VICINITY OF 90 DEGREES BOTH DAYS. CONVECTIVE POTENTIAL HAMPERED
BY THE INCREASING MID LEVEL TEMPERATURES AND LACK OF SUFFICIENT
FORCING BOTH MONDAY AND TUESDAY. NEXT FRONTAL PASSAGE CENTERED
WITHIN THE WEDNESDAY AND WEDNESDAY NIGHT PERIODS...AS THE SOUTHERN
EXTENT OF HEIGHT FALLS ASSOCIATED WITH A DEEPENING WAVE LIFTING INTO
SOUTHERN CANADA ENTERS THE GREAT LAKES. THIS WILL PROVIDE THE NEXT
OPPORTUNITY FOR THUNDERSTORM DEVELOPMENT. COOLER...OR A TRANSITION
BACK TOWARD NORMAL...TEMPERATURES IN THE WAKE OF THE FRONT FOR THE
END OF THE WORK WEEK.
MARINE...
A COLD FRONT ACROSS LAKE HURON AND LOWER MICHIGAN TODAY. THIS FRONT
WILL BRING A CHANCE OF THUNDERSTORMS TO ALL MARINE AREAS. MODERATE
SOUTHWESTERLY WINDS IN ADVANCE OF THIS FRONT...SHIFTING TO NORTH
POST FRONT THROUGH EARLY TONIGHT. WEAK HIGH PRESSURE SETTLING
ACROSS THE REGION WILL BRING FAVORABLE MARINE CONDITIONS SUNDAY
THROUGH EARLY NEXT WEEK.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......RBP
AVIATION.....DRK
SHORT TERM...DRK
LONG TERM....MR
MARINE.......MR
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
753 AM EDT SAT JUL 25 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EDT SAT JUL 25 2015
IT WILL FEEL LIKE THE DOG DAYS OF SUMMER AS WE HEAD THROUGH THE REST
OF THE WEEKEND AND INTO THE MIDDLE PART OF THE WORK WEEK. HIGHS WILL
LIKELY TOP OUT IN THE MIDDLE 80S TODAY WITH UPPER 80S IN MANY AREAS
FOR SUNDAY AND MONDAY. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE
NEXT WEEK AS WE WILL LIKELY PUSH TO OR EXCEED 90 DEGREES. A
WEAKENING COLD FRONT IS EXPECTED TO SLIDE THROUGH SOUTHWEST LOWER
MICHIGAN TODAY AND BRING WITH IT SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WIDESPREAD PRECIPITATION IS NOT EXPECTED...IN FACT MANY
AREAS WILL REMAIN DRY. FAIR AND DRY WEATHER IS ON TAP FOR SUNDAY
INTO EARLY NEXT WEEK AS HIGH PRESSURE WILL BE SITUATED OVER THE
AREA.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
CONCERNS IN THE SHORT TERM ARE RELATED TO SHOWER AND STORM CHANCES
TODAY AND THEN TWEAKING HIGH TEMPERATURES THE NEXT COUPLE DAYS AS WE
WILL BE QUITE WARM.
AS FOR CONVECTION TODAY...IT LOOKS LESS AND LESS IMPRESSIVE WITH
EACH MODEL RUN. THE HRRR GUIDANCE IS ONLY SHOWING SCATTERED STORMS
AT BEST. THE LATEST RAP GUIDANCE IS INDICATING MOST UNSTABLE CAPE
VALUES OF 1000-2000 J/KG WHICH IS MORE THAN ENOUGH...BUT OTHER
FACTORS LIMIT THE THREAT. THEY ARE NAMELY...THE MAIN SHORTWAVE IS
WELL NORTH OF THE AREA AND A WIND OFF THE LAKE WILL LIKELY TEMPER
INSTABILITY DURING THE AFTERNOON. MID LEVEL LAPSE RATES ARE NOT
STEEP EITHER...ON THE ORDER OF 5.5 C/KM. THE LLJ AND 850MB MOISTURE
TRANSPORT HAVE TRENDED DOWN AS WELL. BOTTOM LINE...LOOKING FOR
SCATTERED STORMS TO DEVELOP MIDDAY AND WORK SOUTH/EAST OUT OF THE
AREA DURING THE AFTERNOON HOURS. ANY CHANCE OF A STRONG STORM WOULD
BE DURING THE AFTERNOON TOWARDS LAN/BTL/JXN.
OTHERWISE FAIR WEATHER IS EXPECTED WITH HIGH PRESSURE BUILDING IN
BEHIND THE WEAKENING COLD FRONT. AFTER TODAY WITH CLOUDS ASSOCIATED
WITH THE FRONT...SKIES SHOULD BE MAINLY CLEAR. THINKING WE WILL PUSH
INTO THE MID 80S TODAY...CLOUD COVER IS A BIT OF A CONCERN WHICH
COULD TREND THINGS EITHER SIDE OF THOSE NUMBERS. UPPER 80S LOOK
PRETTY SOLID FOR SUNDAY AND MONDAY GIVEN 850MB TEMPS IN THE 17-19C
RANGE.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
OUR MAIN FOCUS OF THE LONG TERM IS THE FRONTAL PASSAGE THAT IS
EXPECTED DURING THE MID-WEEK TIME FRAME...AND THE CHCS OF CONVECTION
THAT WILL ACCOMPANY THE FRONT.
THE BEGINNING OF THE PERIOD IS EXPECTED TO BE HOT AND HUMID WITH
LITTLE CHCS OF RAIN INITIALLY. WE WILL HAVE A FAIRLY DECENT UPPER
RIDGE IN PLACE. THIS UPPER RIDGE WITH HIGH HEIGHTS WILL SUPPORT THE
HOT WEATHER AND WILL CAP THE ATMOSPHERE OFF FROM ANY PCPN FROM
OCCURRING. WE ARE LOOKING AT A GOOD CHANCE OF LOWER 90S ON TUE WITH
H850 TEMPS APPROACHING 20C.
THERE IS A LITTLE UNCERTAINTY WITH THE SPECIFIC TIMING OF THE
SHOWERS/STORMS WITH THE FRONT MID-WEEK. THE CONSENSUS OF THE CHC OF
SHOWERS/STORMS LOOKS TO OCCUR TUE NIGHT INTO WED. SOME MODELS ARE A
LITTLE EARLIER...AND SOME ARE A LITTLE LATER. IT DOES NOT LOOK LIKE
A STRONG FEED OF GULF MOISTURE WILL BE PRESENT. ENOUGH SHOULD BE
AROUND WITH THE STRENGTH OF THE FRONT TO BRING A DECENT CHC OF RAIN.
SEVERE CHCS ARE NOT LOOKING REAL STRONG AT THIS POINT. THERE DOES
LOOK TO BE A GOOD DEAL OF INSTABILITY PRESENT...ESPECIALLY DURING
PEAK HEATING ON WED. DEEP LAYER SHEAR IS LACKING A BIT WITH THE
BETTER WIND FIELDS LAGGING THE FRONT/STORMS A BIT. WE WILL CONTINUE
TO MONITOR THIS POTENTIAL AND THE TRENDS OVER THE NEXT FEW DAYS.
WE WILL SEE A COOL DOWN ALONG WITH DRIER CONDITIONS FOR THE THU AND
FRI TIME FRAME. WE WILL SEE A TROUGH OVER THE AREA EVENTUALLY GIVING
WAY TO A SFC RIDGE. NW FLOW ALOFT AND IN THE LOWER LEVELS WILL COOL
US OFF A BIT. IT DOES NOT LOOK TOO COLD AT THIS TIME WITH H850 TEMPS
DROPPING INTO THE LOWER TEENS C.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 753 AM EDT SAT JUL 25 2015
CUMULUS CLOUDS ARE EXPECTED TO FILL IN THIS MORNING...TAKING
CONDITIONS BROKEN AT ALL TAF SITES. CEILINGS FOR THE MOST PART
WILL BE IN THE 3500-5000FT RANGE...BUT FOR A TIME FROM
15Z-18Z...KMKG AND KGRR WILL LIKELY GO MVFR WITH CEILINGS JUST
BELOW OR NEAR 3000FT.
A WEAK COLD FRONT WILL BE SLIDING SOUTH THROUGH THE AREA TODAY AND
SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT CAN BE EXPECTED. AT
THIS POINT COVERAGE LOOKS TO BE SOMEWHAT SPARSE AND THEREFORE ONLY
HAVE VCSH WORDING IN THE TAFS.
SKIES WILL CLEAR OUT THIS EVENING AND REMAIN THAT WAY OVERNIGHT.
THERE MAY BE SOME LIGHT FOG LATE TONIGHT...BUT DECIDED TO HOLD OFF
ADDING ANOTHER FORECAST GROUP INTO THE 12Z TAFS.
&&
.MARINE...
ISSUED AT 330 AM EDT SAT JUL 25 2015
WAVES OF 1 TO 3 FEET ARE EXPECTED THIS MORNING FROM GRAND HAVEN
NORTHWARD IN A ZONE WHERE SOUTHWEST WINDS OF 10 TO 20 KNOTS WILL
BUILD WAVE HEIGHTS. WINDS LOOK A BIT DOWN FROM WHAT WE WERE SEEING
IN THE MODELS THE LAST COUPLE NIGHTS...SO THE MORE WIDESPREAD 2 TO 4
FOOT WAVES LOOK LESS LIKELY.
AFTER THIS MORNING...QUIET WEATHER OUT ON THE BIG LAKE THE REST OF
THE WEEKEND WITH HIGH PRESSURE IN PLACE. WAVES OF 2 FEET OR LESS AND
WINDS LESS THAN 15 KNOTS SHOULD BE COMMON PLACE.
&&
.HYDROLOGY...
ISSUED AT 1156 AM EDT FRI JUL 24 2015
RIVER LEVELS ARE FALLING AND ARE WELL BELOW BANKFULL. WITH UNDER
AN INCH OF PRECIPITATION EXPECTED THROUGH THE WEEK... THESE
CONDITIONS SHOULD CONTINUE. LOCALLY HEAVY RAINFALL COULD LEAD TO
PONDING OF WATER... MAINLY SATURDAY OR WEDNESDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...NJJ
AVIATION...DUKE
HYDROLOGY...63
MARINE...DUKE
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
624 AM CDT SAT JUL 25 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 208 AM CDT SAT JUL 25 2015
MAIN CONCERN WILL REVOLVE AROUND HOW WELL MODELS HANDLE CONVECTIVE
EVENTS TODAY AND TONIGHT...THEN TEMPERATURES AS UPPER RIDGE
REBUILDS ACROSS THE PLAINS REGION.
LAST EVENINGS CONVECTIVE COMPLEX ABOUT TO PUSH EAST OF THE CWA AT
08Z WITH STRONGEST CLUSTER OVER SOUTHWEST IOWA AND EXTREME
SOUTHEAST NEBRASKA. 06Z RAP DOWNPLAYS CONVECTION FOR THE MORNING
PERIOD COMPARED TO NAM OR GFS WITH LATTER MODELS FOCUSING ON A
COMPLEX COMING OUT OF SOUTH DAKOTA. PLAN TO FOLLOW THE RAP TREND
THIS MORNING UNLESS NEW DEVELOPMENT INTENSIFIES TO THE WEST...WITH
POPS INCREASING DURING THE AFTERNOON AND TONIGHT. SOME SMALL
CHANCE OF MAINLY OVERNIGHT CONVECTION SUNDAY NIGHT INTO EARLY
MONDAY BUT WARM MID LEVELS AND STRONGER FLOW TO THE NORTHWEST
AHEAD OF A DEEP UPPER TROUGH WILL HINDER DEVELOPMENT.
CLOUDS AND PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
HOLD TEMPERATURES DOWN TODAY. WARMER TEMPS RETURN FOR SUNDAY AND
MONDAY ALTHOUGH WITH NO SURFACE FRONT IN THE AREA WILL BE LIMITED
TO THE LOWER 90S FOR MOST AREAS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 208 AM CDT SAT JUL 25 2015
NEXT COLD FRONT EXPECTED TO COME INTO THE AREA TUESDAY INTO
TUESDAY NIGHT WITH A BETTER CHANCE OF STORMS FOR THE AREA
ASSOCIATED WITH THE FRONT. SOUTH PARTS OF THE AREA COULD SEE
HOT TEMPERATURES AGAIN IN ADVANCE OF THE FRONT ON TUESDAY.
SOME LINGERING PRECIP IN THE FAR SOUTH ON WEDNESDAY BEFORE FRONT
PUSHES FURTHER SOUTH. DEEP UPPER LOW MOVING ACROSS CANADA WILL DIG
A TROUGH IN THE EAST AND RETROGRADE UPPER HIGH CENTER BACK TO THE
SOUTHWEST PART OF THE NATION WEDNESDAY NIGHT THROUGH FRIDAY WITH
SEASONAL TEMPERATURES EXPECTED DURING THAT TIME.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 618 AM CDT SAT JUL 25 2015
VFR CONDITIONS ARE GENERALLY EXPECTED THROUGH THE
PERIOD...ALTHOUGH MVFR CIGS/VISBY POSSIBLE IN SHRA/TSRA. TIMING
AND LOCATION OF ANY SHRA/TSRA ARE HIGHLY UNCERTAIN ATTM...THUS
HAVE LEFT PRECIP OUT OF THE TAFS. ONCE TIMING OF SHRA/TSRA
BECOMES MORE CERTAIN THIS WILL NEED TO BE ADDED. THE MOST LIKELY
SCENARIO APPEARS THAT ANY RA ACTIVITY WOULD OCCUR THIS EVNG INTO
THE OVERNIGHT HOURS. OTHERWISE WE WILL SEE A GOOD DEAL OF MID AND
HIGH LEVEL CLOUDS THROUGH THE PERIOD. WINDS SHOULD REMAIN LIGHT
OUTSIDE OF ANY TSRA.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
947 AM CDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 941 AM CDT SAT JUL 25 2015
MCS ACROSS THE ND/SD BORDER DIURNALLY TRENDING DOWN THIS MORNING
WITH THE CLOUD SHIELD DIMINISHING. SO DID SOME CLOUD AND POP
UPDATES THIS MORNING. TRIMMED POPS BACK JAMES RIVER VALLEY WEST
TO THE MISSOURI RIVER THROUGH EARLY AFTERNOON.
UPDATE ISSUED AT 559 AM CDT SAT JUL 25 2015
QUICK UPDATE TO LOWER POPS AND CONFINE ISOLATED SHOWERS AND
THUNDERSTORMS TO THE FAR SOUTH THROUGH THE MORNING HOURS. THE
RAP13 APPEARS TO HAVE A MUCH BETTER HANDLE THAN THE HRRR IN TERMS
OF MOVING/DEVELOPING AN AREA OF THUNDERSTORMS IN NORTHWESTERN
SOUTH DAKOTA. EARLIER IT APPEARED THAT THIS WOULD MOVE STEADILY
NORTHEAST BUT LATEST TRENDS SUGGEST A MORE EASTWARD MOVEMENT. THIS
WILL LIMIT POPS ACROSS SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA.
IR CLOUDS TOP TEMPS OF -54C REPRESENTS A CIRRUS SHIELD WITH HEIGHTS
BETWEEN 30KFT AND 35KFT. UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CDT SAT JUL 25 2015
THE LATEST WATER VAPOR IMAGERY SHOWS A SOUTHWEST FLOW INTO
WESTERN AND CENTRAL NORTH DAKOTA WITH A FEW EMBEDDED MID LEVEL
SHORTWAVE TROUGHS. THESE SHORTWAVE TROUGHS WERE LOCATED IN
SOUTHEAST MONTANA...NORTHERN WYOMING...AND WESTERN SOUTH DAKOTA.
REGIONAL RADAR SHOWING A GROWING AREA OF SHOWERS AND THUNDERSTORMS
OVER SOUTHEAST MONTANA INTO CENTRAL AND NORTHERN SOUTH DAKOTA.
BOWMAN RADAR ALSO DEPICTS THE LEADING EDGE OF LIGHT SHOWERS
SCOOTING OVER THE FAR SOUTHWEST. MAIN THEME TODAY WILL BE ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS OVER SOUTHWEST NORTH DAKOTA
EARLY THIS MORNING...CONTINUING DURING THE DAY...AND GRADUALLY
EXPANDING INTO CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON AND
EARLY EVENING. ALTHOUGH THE GFS/ECMWF KEEP THE MAXIMUM CAPE AND
0-6KM SHEAR DISPLACED FROM EACH OTHER...VALUES ARE STILL HIGH
ENOUGH FOR THE AFOREMENTIONED SHORTWAVES TO WORK WITH RESULTING IN
STRONG TO ISOLATED SEVERE THUNDERSTORMS TODAY...ESPECIALLY ACROSS
THE SOUTH. SPC HAS THE SLIGHT RISK AREA APPROACHING OUR SOUTHERN
BORDER TODAY WITH MARGINAL CRITERIA COVERING ALL EXCEPT THE FAR
NORTHWEST. THE SHOWERS/THUNDERSTORMS WILL MAINLY RESIDE ACROSS THE
JAMES RIVER VALLEY SATURDAY EVENING/NIGHT AS THE SHORTWAVES
MIGRATE EAST. AFTERNOON HIGHS TODAY WILL REACH WELL INTO THE
80S...WITH LOWER 90S IN THE NORTHWEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CDT SAT JUL 25 2015
ZONAL MID LEVEL FLOW IN THE SHORT TERM TRANSITIONS TO SOUTHWEST
FLOW AS THE WEST COAST TROUGH DEEPENS...AND THEN BEGINS TO PUSH
OVER THE ROCKIES MONDAY. WEAK WAVES IN THE FLOW INTO MONDAY KEEP
LOWER POPS IN THE FORECAST FOR EACH DAY. BY MONDAY...AS THE LONG
WAVE TROUGH APPROACHES...SURFACE LOW PRESSURE OVER EASTERN MONTANA
INTENSIFY WITH STRONG WARM AIR AND MOISTURE ADVECTION INTO
WESTERN NORTH DAKOTA...TEMPERATURES SOLIDLY INTO THE MID 90S...AND
WIND SPEEDS APPROACHING ADVISORY THRESHOLDS.
SEVERE WEATHER PARAMETERS BECOME MORE FAVORABLE LATER MONDAY DUE
IN PART TO THE INCREASING MOISTURE...BUT ALSO IN THE BREAK OUT OF
SUNSHINE IN A CLEAR SLOT...AND NEAR THE FRONTAL TRIPLE POINT.
VERY STRONG THERMODYNAMICS SHOULD ALSO BE PRESENT ACROSS THE
POWERFUL COLD FRONT...FURTHER ENHANCING STORMS. SEVERE STORMS
WILL BE POSSIBLE MONDAY AND MONDAY NIGHT.
FOR TUESDAY A SIGNIFICANT COOL DOWN IS PREDICTED WITH HIGHS IN THE
NORTHWEST PART OF NORTH DAKOTA ONLY REACHING AROUND 70 BEHIND THE
ANOMALOUSLY DEEP SYSTEM...FOR THE END OF JULY...MOVING THROUGH
SOUTHERN SASKATCHEWAN. EXPECT GUSTY WINDS.
DRY FOR THE MIDDLE TO LATTER PARTS OF NEXT WEEK WITH HIGHS MAINLY
IN THE 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 941 AM CDT SAT JUL 25 2015
SURFACE TROUGH ACROSS EASTERN MONTANA WILL BE THE FOCUS FOR
SCATTERED THUNDERSTORMS ACROSS WESTERN AND CENTRAL NORTH DAKOTA
THIS AFTERNOON AND EVENING. VFR CIGS/VSBYS NEXT 24HR. VCTS WILL
BE MAINTAINED FROM EARLY AFTERNOON INTO THE EARLY EVENING TIME
PERIOD AT ALL TERMINALS EXCEPT KISN.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...JPM
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
933 AM CDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 933 AM CDT SAT JUL 25 2015
A FEW SHOWERS HAVE STARTED TO GO UP IN THE NORTHERN VALLEY AS A
WEAK SHORTWAVE HAS BEEN GOING OVER THE TOP OVER THE TOP OF THE
RIDGE. BUMPED UP POPS TO SCATTERED IN THIS AREA AND HAVE IT MOVING
EASTWARD FOR THE REST OF THE DAY. SO FAR IT IS MOSTLY SHOWERS BUT
SOME LIGHTNING IS NOT OF THE QUESTION WITH 1000 J/KG OF ELEVATED
CAPE. THINK THAT THE SHOWERS AND CLOUDS WILL NOT KEEP US FROM
GETTING INTO THE UPPER 80S THIS AFTERNOON AT THIS POINT...BUT
WILL MONITOR.
UPDATE ISSUED AT 641 AM CDT SAT JUL 25 2015
CONVECTION THAT BLEW UP OVER NORTHWESTERN SD IS RESULTING IN
CIRRUS BLOW OFF SPREADING ACROSS SRN ND AND INTO SWRN ZONES. WILL
INCREASE SKY COVER FOR MORNING HOURS ACROSS THE SOUTH. ALSO PATCHY
CLOUDS OVER NORTHERN VALLEY MORE BKN THAN EXPECTED THIS
MORNING...AND WILL ADJUST SKY FOR THIS REGION AS WELL. HI RES
MODELS CONTINUE TO DIFFER WITH CONVECTION ACROSS MAINLY THE
NORTH. CONFIDENCE TOO LOW TO ADD ANY POPS OTHER THAN THE FAR
NORTHEAST...WHICH HAS BEEN A BIT MORE CONSISTENT. NO OTHER CHANGES
PLANNED THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
FORECAST CHALLENGE FOR THE SHORT TERM WILL BE POTENTIAL FOR
CONVECTION MAINLY ACROSS THE SOUTH AND DAYTIME HIGHS FOR WHAT
SHOULD BE A GENERALLY DRY WEEKEND. PREFER HIGHER RES MODELS FOR
PRECIP TRENDS THIS EVENING. A RIDGE AXIS IS CURRENTLY OVER THE
EASTERN CWA...BRINGING CALM WINDS TO MOST OF WEST CENTRAL
MINNESOTA WHILE WEAK RETURN FLOW HAS SET UP OVER EASTERN NORTH
DAKOTA AND THE NORTHERN VALLEY TO INCLUDE FAR NORTHWESTERN MN.
THIS MORNING...CALM WINDS...DEW POINTS AROUND 60 AND CLEAR SKIES
ARE RESULTING IN SOME PATCHY FOG ACROSS W CNTRL MN. HAVE PUT
PATCHY FOG INTO FCST THROUGH 13Z TO 14Z TIMEFRAME. MAY SEE SOME
IMPROVEMENT ADJACENT TO THE VALLEY AS WINDS PICK UP AND TURN
SOUTHERLY...BUT SHOULD HOLD OFF UNTIL MID MORNING BURN OFF IN
EASTERN ZONES.
RETURN FLOW WILL SET UP AND WESTERN ZONES SHOULD SEE SOME
INCREASED INSTABILITY...HOWEVER THE BEST INSTABILITY WILL
GENERALLY BE ACROSS WRN ND AND SD WITH WEAK SUBSIDENCE OVER OUR
AREA AS LOW AMPLITUDE UPPER RIDGE MOVES ACROSS AREA. MODELS ARE
SHOWING WEAK SHORTWAVES CONTINUING TO RIDE NORTHERN EDGE OF THE
UPPER RIDGE AND DEVELOP CONVECTION ACROSS SRN MANITOBA WILE A
STRONGER WAVE WILL MOVE ACROSS SD WHERE SPC HAS A SLIGHT RISK FOR
DAY 1. DEEP LAYER SHEAR CURRENTLY AROUND 40 KTS WILL WEAKEN
THROUGH THE DAY AS UPPER RIDGE MOVES ACROSS ND...WHILE WRN ND WILL
SEE AN INCREASE IN INSTABILITY BY LATE AFTN. THINK BEST CHANCE FOR
STORMS WILL BE ALONG SD BORDER OR WRN ZONES WHERE STORMS
DEVELOPING OVER WRN/CNTRL ND AND ADVECT INTO DVL AREA. ECMWF/GFS
APPEAR RATHER BULLISH FOR CONVECTION IN FAR WRN ND BUT MOST MODELS
IN AGREEMENT WITH CONVECTION DYING OFF OVERNIGHT. WILL KEEP LOW
CHANCE POPS IN THE FAR WEST/SOUTH WITH MAJORITY OF CWA DRY. ALSO
ADDED LOW POPS IN THE FAR NORTHEAST AS HRRR CONTINUES TO SHOW SOME
WEAK STORMS RIDING OVER THE RIDGE AND CROSS LAKE OF THE
WOODS...NORTHERN BELTRAMI COUNTIES.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
SUNDAY NIGHT INTO MONDAY...UPPER RIDGE OVER EASTERN ZONES WHILE
WE SLOWLY TRANSITION FROM A MORE ZONAL TO SOUTHWESTERLY FLOW
PATTERN IN THE WEST BY 00Z MON. SHOULD SEE PLENTY OF SUNSHINE AND
TEMPS AROUND 90 F FOR DAYTIME HIGHS BOTH DAYS. WILL SEE CONVECTION
BEGIN TO DEVELOP OVER ERN MT AND WRN ND LATE IN THE DAY...MOSTLY
DRY OVER OUR AREA. WEAK LOW PRESSURE OVER SASK/MB REGION WILL
INTERACT WITH A SERIES OF WEAK SHORT WAVES EMBEDDED IN SW
FLOW...AND BRING A CHANCE FOR TSTMS TO NW ZONES AND ALONG THE INTL
BORDER. A MORE SIGNIFICANT LOW PRESSURE SYSTEM THEN DEVELOPS MON
NIGHT OVER MT/WY AND WILL BRING A FRONT ACROSS THE AREA EARLY IN
THE NEXT WORK WEEK. HAVE CONTINUED LIKELY POPS IN THE FAR
NORTHWESTERN ZONES AS STORMS CONTINUE ACROSS SRN CANADA.
FOR TUE THROUGH FRI...THERE COULD BE SOME CONVECTION ON TUE
DEPENDING ON TIMING OF A FRONT THAT WILL MOVE THROUGH THE AREA.
THEREAFTER...TEMPS SHOULD COOL DOWN BELOW NORMAL BY WED. THERE COULD
BE SOME CONVECTION IN THE NORTH WED CLOSER TO CYCLONIC FLOW...BUT
OVERALL NOT EXPECTING TOO MUCH COVERAGE OF SHOWERS OR STORMS. FOR
THU/FRI...EXPECT TEMPS RISING TO AROUND NORMAL WITH MAINLY DRY
WEATHER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 641 AM CDT SAT JUL 25 2015
VFR THROUGHOUT TAF PERIOD. WILL CONTINUE TEMPO FOR EARLY MORNING
MIST AT BJI THROUGH 13Z...HOWEVER THIS HAS BEGAN TO CLEAR OUT.
WILL SEE MID CLOUD MOVE INTO DVL REGION THIS EVENING BUT NOT
ENOUGH CONFIDENCE FOR CONVECTION TO ADD AT DVL OR FAR AT THIS
TIME.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...SPEICHER
LONG TERM...DK/SPEICHER
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
641 AM CDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 641 AM CDT SAT JUL 25 2015
CONVECTION THAT BLEW UP OVER NORTHWESTERN SD IS RESULTING IN
CIRRUS BLOW OFF SPREADING ACROSS SRN ND AND INTO SWRN ZONES. WILL
INCREASE SKY COVER FOR MORNING HOURS ACROSS THE SOUTH. ALSO PATCHY
CLOUDS OVER NORTHERN VALLEY MORE BKN THAN EXPECTED THIS
MORNING...AND WILL ADJUST SKY FOR THIS REGION AS WELL. HI RES
MODELS CONTINUE TO DIFFER WITH CONVECTION ACROSS MAINLY THE
NORTH. CONFIDENCE TOO LOW TO ADD ANY POPS OTHER THAN THE FAR
NORTHEAST...WHICH HAS BEEN A BIT MORE CONSISTENT. NO OTHER CHANGES
PLANNED THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
FORECAST CHALLENGE FOR THE SHORT TERM WILL BE POTENTIAL FOR
CONVECTION MAINLY ACROSS THE SOUTH AND DAYTIME HIGHS FOR WHAT
SHOULD BE A GENERALLY DRY WEEKEND. PREFER HIGHER RES MODELS FOR
PRECIP TRENDS THIS EVENING. A RIDGE AXIS IS CURRENTLY OVER THE
EASTERN CWA...BRINGING CALM WINDS TO MOST OF WEST CENTRAL
MINNESOTA WHILE WEAK RETURN FLOW HAS SET UP OVER EASTERN NORTH
DAKOTA AND THE NORTHERN VALLEY TO INCLUDE FAR NORTHWESTERN MN.
THIS MORNING...CALM WINDS...DEW POINTS AROUND 60 AND CLEAR SKIES
ARE RESULTING IN SOME PATCHY FOG ACROSS W CNTRL MN. HAVE PUT
PATCHY FOG INTO FCST THROUGH 13Z TO 14Z TIMEFRAME. MAY SEE SOME
IMPROVEMENT ADJACENT TO THE VALLEY AS WINDS PICK UP AND TURN
SOUTHERLY...BUT SHOULD HOLD OFF UNTIL MID MORNING BURN OFF IN
EASTERN ZONES.
RETURN FLOW WILL SET UP AND WESTERN ZONES SHOULD SEE SOME
INCREASED INSTABILITY...HOWEVER THE BEST INSTABILITY WILL
GENERALLY BE ACROSS WRN ND AND SD WITH WEAK SUBSIDENCE OVER OUR
AREA AS LOW AMPLITUDE UPPER RIDGE MOVES ACROSS AREA. MODELS ARE
SHOWING WEAK SHORTWAVES CONTINUING TO RIDE NORTHERN EDGE OF THE
UPPER RIDGE AND DEVELOP CONVECTION ACROSS SRN MANITOBA WILE A
STRONGER WAVE WILL MOVE ACROSS SD WHERE SPC HAS A SLIGHT RISK FOR
DAY 1. DEEP LAYER SHEAR CURRENTLY AROUND 40 KTS WILL WEAKEN
THROUGH THE DAY AS UPPER RIDGE MOVES ACROSS ND...WHILE WRN ND WILL
SEE AN INCREASE IN INSTABILITY BY LATE AFTN. THINK BEST CHANCE FOR
STORMS WILL BE ALONG SD BORDER OR WRN ZONES WHERE STORMS
DEVELOPING OVER WRN/CNTRL ND AND ADVECT INTO DVL AREA. ECMWF/GFS
APPEAR RATHER BULLISH FOR CONVECTION IN FAR WRN ND BUT MOST MODELS
IN AGREEMENT WITH CONVECTION DYING OFF OVERNIGHT. WILL KEEP LOW
CHANCE POPS IN THE FAR WEST/SOUTH WITH MAJORITY OF CWA DRY. ALSO
ADDED LOW POPS IN THE FAR NORTHEAST AS HRRR CONTINUES TO SHOW SOME
WEAK STORMS RIDING OVER THE RIDGE AND CROSS LAKE OF THE
WOODS...NORTHERN BELTRAMI COUNTIES.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
SUNDAY NIGHT INTO MONDAY...UPPER RIDGE OVER EASTERN ZONES WHILE
WE SLOWLY TRANSITION FROM A MORE ZONAL TO SOUTHWESTERLY FLOW
PATTERN IN THE WEST BY 00Z MON. SHOULD SEE PLENTY OF SUNSHINE AND
TEMPS AROUND 90 F FOR DAYTIME HIGHS BOTH DAYS. WILL SEE CONVECTION
BEGIN TO DEVELOP OVER ERN MT AND WRN ND LATE IN THE DAY...MOSTLY
DRY OVER OUR AREA. WEAK LOW PRESSURE OVER SASK/MB REGION WILL
INTERACT WITH A SERIES OF WEAK SHORT WAVES EMBEDDED IN SW
FLOW...AND BRING A CHANCE FOR TSTMS TO NW ZONES AND ALONG THE INTL
BORDER. A MORE SIGNIFICANT LOW PRESSURE SYSTEM THEN DEVELOPS MON
NIGHT OVER MT/WY AND WILL BRING A FRONT ACROSS THE AREA EARLY IN
THE NEXT WORK WEEK. HAVE CONTINUED LIKELY POPS IN THE FAR
NORTHWESTERN ZONES AS STORMS CONTINUE ACROSS SRN CANADA.
FOR TUE THROUGH FRI...THERE COULD BE SOME CONVECTION ON TUE
DEPENDING ON TIMING OF A FRONT THAT WILL MOVE THROUGH THE AREA.
THEREAFTER...TEMPS SHOULD COOL DOWN BELOW NORMAL BY WED. THERE COULD
BE SOME CONVECTION IN THE NORTH WED CLOSER TO CYCLONIC FLOW...BUT
OVERALL NOT EXPECTING TOO MUCH COVERAGE OF SHOWERS OR STORMS. FOR
THU/FRI...EXPECT TEMPS RISING TO AROUND NORMAL WITH MAINLY DRY
WEATHER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 641 AM CDT SAT JUL 25 2015
VFR THROUGHOUT TAF PERIOD. WILL CONTINUE TEMPO FOR EARLY MORNING
MIST AT BJI THROUGH 13Z...HOWEVER THIS HAS BEGAN TO CLEAR OUT.
WILL SEE MID CLOUD MOVE INTO DVL REGION THIS EVENING BUT NOT
ENOUGH CONFIDENCE FOR CONVECTION TO ADD AT DVL OR FAR AT THIS
TIME.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...SPEICHER
LONG TERM...DK/SPEICHER
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
559 AM CDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 559 AM CDT SAT JUL 25 2015
QUICK UPDATE TO LOWER POPS AND CONFINE ISOLATED SHOWERS AND
THUNDERSTORMS TO THE FAR SOUTH THROUGH THE MORNING HOURS. THE
RAP13 APPEARS TO HAVE A MUCH BETTER HANDLE THAN THE HRRR IN TERMS
OF MOVING/DEVELOPING AN AREA OF THUNDERSTORMS IN NORTHWESTERN
SOUTH DAKOTA. EARLIER IT APPEARED THAT THIS WOULD MOVE STEADILY
NORTHEAST BUT LATEST TRENDS SUGGEST A MORE EASTWARD MOVEMENT. THIS
WILL LIMIT POPS ACROSS SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA.
IR CLOUDS TOP TEMPS OF -54C REPRESENTS A CIRRUS SHIELD WITH HEIGHTS
BETWEEN 30KFT AND 35KFT. UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CDT SAT JUL 25 2015
THE LATEST WATER VAPOR IMAGERY SHOWS A SOUTHWEST FLOW INTO
WESTERN AND CENTRAL NORTH DAKOTA WITH A FEW EMBEDDED MID LEVEL
SHORTWAVE TROUGHS. THESE SHORTWAVE TROUGHS WERE LOCATED IN
SOUTHEAST MONTANA...NORTHERN WYOMING...AND WESTERN SOUTH DAKOTA.
REGIONAL RADAR SHOWING A GROWING AREA OF SHOWERS AND THUNDERSTORMS
OVER SOUTHEAST MONTANA INTO CENTRAL AND NORTHERN SOUTH DAKOTA.
BOWMAN RADAR ALSO DEPICTS THE LEADING EDGE OF LIGHT SHOWERS
SCOOTING OVER THE FAR SOUTHWEST. MAIN THEME TODAY WILL BE ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS OVER SOUTHWEST NORTH DAKOTA
EARLY THIS MORNING...CONTINUING DURING THE DAY...AND GRADUALLY
EXPANDING INTO CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON AND
EARLY EVENING. ALTHOUGH THE GFS/ECMWF KEEP THE MAXIMUM CAPE AND
0-6KM SHEAR DISPLACED FROM EACH OTHER...VALUES ARE STILL HIGH
ENOUGH FOR THE AFOREMENTIONED SHORTWAVES TO WORK WITH RESULTING IN
STRONG TO ISOLATED SEVERE THUNDERSTORMS TODAY...ESPECIALLY ACROSS
THE SOUTH. SPC HAS THE SLIGHT RISK AREA APPROACHING OUR SOUTHERN
BORDER TODAY WITH MARGINAL CRITERIA COVERING ALL EXCEPT THE FAR
NORTHWEST. THE SHOWERS/THUNDERSTORMS WILL MAINLY RESIDE ACROSS THE
JAMES RIVER VALLEY SATURDAY EVENING/NIGHT AS THE SHORTWAVES
MIGRATE EAST. AFTERNOON HIGHS TODAY WILL REACH WELL INTO THE
80S...WITH LOWER 90S IN THE NORTHWEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CDT SAT JUL 25 2015
ZONAL MID LEVEL FLOW IN THE SHORT TERM TRANSITIONS TO SOUTHWEST
FLOW AS THE WEST COAST TROUGH DEEPENS...AND THEN BEGINS TO PUSH
OVER THE ROCKIES MONDAY. WEAK WAVES IN THE FLOW INTO MONDAY KEEP
LOWER POPS IN THE FORECAST FOR EACH DAY. BY MONDAY...AS THE LONG
WAVE TROUGH APPROACHES...SURFACE LOW PRESSURE OVER EASTERN MONTANA
INTENSIFY WITH STRONG WARM AIR AND MOISTURE ADVECTION INTO
WESTERN NORTH DAKOTA...TEMPERATURES SOLIDLY INTO THE MID 90S...AND
WIND SPEEDS APPROACHING ADVISORY THRESHOLDS.
SEVERE WEATHER PARAMETERS BECOME MORE FAVORABLE LATER MONDAY DUE
IN PART TO THE INCREASING MOISTURE...BUT ALSO IN THE BREAK OUT OF
SUNSHINE IN A CLEAR SLOT...AND NEAR THE FRONTAL TRIPLE POINT.
VERY STRONG THERMODYNAMICS SHOULD ALSO BE PRESENT ACROSS THE
POWERFUL COLD FRONT...FURTHER ENHANCING STORMS. SEVERE STORMS
WILL BE POSSIBLE MONDAY AND MONDAY NIGHT.
FOR TUESDAY A SIGNIFICANT COOL DOWN IS PREDICTED WITH HIGHS IN THE
NORTHWEST PART OF NORTH DAKOTA ONLY REACHING AROUND 70 BEHIND THE
ANOMALOUSLY DEEP SYSTEM...FOR THE END OF JULY...MOVING THROUGH
SOUTHERN SASKATCHEWAN. EXPECT GUSTY WINDS.
DRY FOR THE MIDDLE TO LATTER PARTS OF NEXT WEEK WITH HIGHS MAINLY
IN THE 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 559 AM CDT SAT JUL 25 2015
VFR CIGS/VSBYS NEXT 24HR. HOWEVER A VCTS WILL BE MAINTAINED FROM
EARLY AFTERNOON INTO THE EARLY EVENING TIME PERIOD AT ALL
TERMINALS EXCEPT KISN.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...KS
LONG TERM...JPM
AVIATION...KS
AREA FORECAST DISCUSSION
NWS TULSA OK
1017 AM CDT SAT JUL 25 2015
.DISCUSSION...
MORNING UPPER AIR DATA SUGGESTS THAT THE MID LEVEL RIDGE HAS
WEAKENED A LITTLE OVER OKLAHOMA AND ARKANSAS COMPARED TO
YESTERDAY. BOTH THE NAM AND HRRR SUGGEST AT LEAST ISOLATED STORM
DEVELOPMENT OVER ARKANSAS THIS AFTERNOON...MAINLY TO THE EAST OF
THE TULSA WFO FORECAST AREA WHERE 500MB ARE COOLER AND HEIGHTS ARE
LOWER. THERE IS ENOUGH OF A CONSISTENT SIGNAL IN THE AVAILABLE
DATA TO INSERT A SLIGHT CHANCE OF AFTERNOON STORMS EAST OF THE
I-49 CORRIDOR IN NORTHWEST ARKANSAS. NO OTHER CHANGES WERE NEEDED.
HEAT HEADLINES REMAIN INTACT.
LACY
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 99 77 99 77 / 0 0 10 0
FSM 99 77 99 77 / 10 0 0 0
MLC 97 73 97 73 / 0 0 0 0
BVO 97 73 97 73 / 0 0 10 0
FYV 94 71 94 71 / 10 0 0 0
BYV 94 72 94 72 / 10 0 10 10
MKO 95 74 95 74 / 0 0 0 0
MIO 96 74 96 74 / 0 0 10 0
F10 96 74 96 74 / 0 0 0 0
HHW 97 74 97 74 / 0 0 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR OKZ049-053-063-068-
069-073-075.
EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR
OKZ054>062-064>067-070>072-074-076.
AR...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ARZ001-002-010-011.
EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR ARZ019-
020-029.
&&
$$
SHORT TERM...30
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
959 AM CDT SAT JUL 25 2015
.UPDATE...
THERE COULD BE SOME LATE MORNING AND AFTERNOON CUMULUS DEVELOPMENT
TODAY...BUT OTHERWISE EXPECT DECREASING CLOUDS AS HIGH PRESSURE
BUILDS INTO THE AREA. STILL EXPECTING MID TO UPPER 80S UNDER 925
MB TEMPS OF 23-25 C...WITH A FEW SPOTS POSSIBLY CRACKING 90. IT
WILL BE A TAD COOLER NEAR LAKE MICHIGAN...WHERE WINDS WILL TURN
ONSHORE FOR THE AFTERNOON.
&&
.AVIATION/18Z TAFS/...
VFR CONDITIONS SHOULD PREVAIL THROUGH SUNDAY...AS HIGH PRESSURE
SLIDES EASTWARD THROUGH THE AREA. SOME FOG MAY TRY TO DEVELOP
TONIGHT AS THE HIGH BRINGS LIGHT TO CALM WINDS....BUT THERE ARE
SOME INDICATIONS OF A MID LEVEL CLOUD DECK THAT COULD DISRUPT THE
FOG POTENTIAL.
MAY SEE A FEW SHOWERS/STORMS DEVELOP IN THE FAR WEST OR SOUTHWEST
LATER SUNDAY AS THE HIGH HEADS EAST. MODELS HAVE BEEN TRENDING
DRIER THOUGH...HOLDING ONTO THE HIGH A BIT LONGER.
&&
.PREV DISCUSSION... /ISSUED 432 AM CDT SAT JUL 25 2015/
TODAY...FORECAST CONFIDENCE IS MEDIUM.
EARLIER SCATTERED TO ISOLATED CONVECTION UPSTREAM OVER WEST
CENTRAL WI DIED OUT AS IT MOVED INTO INCREASING CONVECTIVE
INHIBITION OVER SOUTHERN AND EASTERN WI...REFLECTED IN CAP BETWEEN
800 MB AND 700 MB ON BLUE RIVER RAP FORECAST SOUNDING.
THE INHIBITION DOES LOWER IN A CORRIDOR COINCIDENT WITH THE
SURFACE FRONT WITH A FEW CELLS POPPING UP ALONG THE FRONT...BUT
THEY ARE WEAK AND SHORT-LIVED WITH THE CAP AND LITTLE IN THE WAY
OF UPPER SUPPORT WITH AREA UNDER THE RIGHT EXIT REGION OF A 300 MB
JET MAXIMA AND CVA WITH THE SHORT WAVE DRIVING THE CONVECTION OVER
NE WI TO NRN LAKE MICHIGAN.
WITH HI-RES/RAPID UPDATE MODELS STILL SHOWING POTENTIAL OF
SCATTERED TO ISOLATED SHOWERS WITH A STORM OR TWO AS FRONT CROSSES
FORECAST AREA WILL KEEP A COLLABORATIVE SLIGHT CHANCE ALONG THE
FRONT...EXITING TO THE SOUTHEAST BY 15Z THOUGH A DRY FRONTAL
PASSAGE IS A STRONG POSSIBILITY.
HIGH PRESSURE SETTLES OVER THE REGION BUT MODELS STILL SHOW 925
MB TEMPS A FEW DEGREES WARMER THAN FRIDAY. WILL KEEP UPPER 80S
HIGHS INLAND WITH A COOLING LAKE BREEZE DEVELOPING BY EARLY
AFTERNOON HOLDING HIGHS IN THE UPPER 70S TO LOW 80S ALONG THE
LAKE.
TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
FRONT STALLS TO THE SOUTH...WITH MODELS DEPICTING A SHORT WAVE
APPROACHING FROM THE WEST...WITH A CONSENSUS POSITION OVER SRN
MN/NRN IA BY 12Z SUNDAY. BETTER RETURN FLOW STAYS WEST OF CWA
THROUGH 12Z SUNDAY...BUT WITH SOME OMEGA AND ELEVATED CAPE SHOWN
ON NAM DBQ FORECAST SOUNDINGS AFTER 09Z...THOUGH LITTLE OMEGA AND
CAPE ON BLUE RIVER SOUNDING... WILL HAVE SLIGHT CHANCE POPS AFTER
09Z IN THE FAR SW CWA. LOWS IN THE MID 60S.
SHORT TERM...SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
MODELS ARE IN DECENT AGREEMENT WITH A 500 MB RIDGE AXIS BUILDING
ACROSS THE UPPER MIDWEST REGION SUNDAY AND SUNDAY NIGHT...SHIFTING
SLOWLY EASTWARD MONDAY INTO MONDAY NIGHT. MODELS SHOWING SEVERAL
WEAK VORTICITY MAXIMA MOVING THROUGH THE REGION...WITH SOME TIMING
AND PLACEMENT DIFFERENCES. HIGH PRESSURE AT THE SURFACE REMAINS
EAST OF THE AREA DURING THE SHORT TERM PERIOD.
THE NAM/CANADIAN/ECMWF MODELS KEEP MOST PRECIPITATION TO THE WEST
AND SOUTH OF THE AREA DURING THIS TIME...WITH THE INFLUENCE OF THE
HIGH. THE GFS IS THE ONLY MODEL TO PRODUCE ROUNDS OF QPF AT TIMES
DURING THIS PERIOD. GFS FORECAST SOUNDINGS APPEAR TO BE OVERDONE
SOMEWHAT WITH DEW POINTS...WHICH MAY BE LEADING TO THE QPF
FORECASTS. THINK THE GFS IS OVERDONE...AS THERE ARE NO SIGNIFICANT
FEATURES TO PRODUCE THE QPF IT IS SHOWING.
THUS...LEANED TOWARDS THE NAM/CANADIAN/ECMWF AND LOWERED POPS
DURING THE SHORT TERM PERIOD. WOULD NOT BE SURPRISED TO SEE THIS
PERIOD END UP DRY. WARM 925 MB TEMPERATURES AND SOME SUNSHINE
SHOULD RESULT IN WARM AND HUMID DAYS SUNDAY AND MONDAY...WITH
HIGHS INTO THE MIDDLE TO UPPER 80S EACH DAY. THEY COULD INCH A
DEGREE OR TWO HIGHER THAN CURRENTLY FORECAST. ONSHORE WINDS WILL
KEEP LAKESHORE AREAS SOMEWHAT COOLER.
LONG TERM...TUESDAY THROUGH FRIDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF MODELS ARE IN DECENT AGREEMENT WITH WARM AND HUMID
CONDITIONS LINGERING TUESDAY INTO TUESDAY NIGHT...BEFORE A COLD
FRONT MOVES THROUGH THE REGION LATE TUESDAY NIGHT INTO WEDNESDAY
MORNING. A BROAD 500 MB TROUGH PASSES THROUGH THE REGION WEDNESDAY
AS WELL...WITH EMBEDDED VORTICITY MAXIMA. THUS...KEPT POPS GOING
FOR THE TUESDAY INTO WEDNESDAY PERIOD...HIGHEST TUESDAY NIGHT. MAY
NEED HIGHER POPS TUESDAY NIGHT/EARLY WEDNESDAY IF THEY REMAIN
CONSISTENT WITH THE FRONTAL PASSAGE TIMING.
SOMEWHAT COOLER AND LESS HUMID CONDITIONS THEN MOVE INTO THE
REGION FOR LATER WEDNESDAY INTO FRIDAY ACROSS THE REGION...AS
HIGH PRESSURE MOVES INTO THE CENTRAL PLAINS. MOST OF THIS PERIOD
LOOKS DRY AT THIS TIME.
AVIATION/12Z TAFS/...
EXCEPT FOR A FEW BRIEF ISOLATED SHOWERS/SPRINKLES POPPING UP
ALONG THE COOL FRONT...MOST AREAS LOOK TO REMAIN DRY AS THE FRONT
MOVES THROUGH THE AREA. WILL REMOVE VICINITY THUNDER AS ANY PCPN
THAT DOES REACH A TAF SITE WILL BE A LIGHT SHOWER AT MOST. FRONT
CLEARS THE FAR SOUTHEAST CORNER BETWEEN 15Z AND 16Z ENDING ANY
PCPN CHANCES.
MAINLY VFR CLOUDS WITH FRONT...BUT SOME SCT-BKN MVFR CLOUDS RIGHT
BEHIND THE FRONT THAT COULD AFFECT TAF SITES FOR AN HOUR OR TWO
AFTER FRONTAL PASSAGE. WILL WATCH TRENDS UP TO ISSUANCE TO SEE IF
LOWER CLOUDS EXPAND IN COVERAGE.
VFR CONDITIONS FOR REMAINDER OF FORECAST WITH AN EASTERLY LAKE
BREEZE DEVELOPING EARLY THIS AFTERNOON THAT SHOULD PUSH WEST TO
KUES BY LATE AFTERNOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION...REM
SUNDAY THROUGH FRIDAY...WOOD
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
545 AM MDT SAT JUL 25 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 315 AM MDT SAT JUL 25 2015
WATER VAPOR IMAGERY SHOWED A STATIONARY UPPER RIDGE OVER THE
SOUTH CENTRAL CONUS WITH ACTIVE WESTERLY FLOW OVER THE NORTH
CENTRAL CONUS. SUBTROPICAL MOISTURE AND WEAK WAVES CIRCULATING
CLOCKWISE AROUND THE UPPER HIGH AIDED IN SEVERAL CLUSTERS OF
DEEP CONVECTION FROM THE CENTRAL PLAINS INTO THE LOWER/MID MS
VALLEY. A COMPLEX OF TSTORMS DEVELOPED ACROSS NORTHEAST WY
ASSOCIATED WITH THE LEFT FRONT QUADRANT OF UPPER JET STREAK.
THIS COMPLEX WILL CONTINUE TO TRACK EAST-NORTHEAST ACROSS
NORTHWEST SD OVERNIGHT. SURFACE ANALYSIS DEPICTED A WAVY FRONT
FROM A LOW IN NORTH CENTRAL IA ACROSS SOUTHERN NE...NORTHWEST KS
AND EAST CENTRAL CO THEN CURVING NORTHWEST INTO EASTERN WY. BACK
EDGE OF CIRRUS WAS MOVING THROUGH WESTERN NE LEAVING MOSTLY CLEAR
SKIES TO THE WEST.
THE LARGE SCALE PATTERN WE`VE BEEN ACCUSTOMED TO THE PAST SEVERAL
DAYS WILL CONTINUE WITH A CENTRAL CONUS RIDGE FLANKED BY TROUGHS
TO THE WEST AND EAST. ISOLATED CONVECTION DEVELOPED OVER THE
PLAINS LATE FRIDAY ALONG A INSTABILITY GRADIENT. THE GRADIENT
WILL SHIFT EAST OF THE CWA TODAY...HOWEVER JET ENERGY COMBINED
WITH LINGERING MID LEVEL MOISTURE MAY TRIGGER ISOLATED AFTERNOON
CONVECTION ACROSS THE HIGH PLAINS. THE MAJORITY OF THE MODELS
MAINTAIN DRY CONDITIONS...HOWEVER THE HRRR GENERATES A 20-30
PERCENT COVERAGE OF CONVECTION. NOT TOTALLY BUYING THE HRRR...WITH
10-15 PERCENT POPS FORECAST ATTM. 700MB TEMPERATURES PEAK NEAR 15C
TODAY WITH AFTERNOON HIGHS IN THE UPPER 80S-MID 90S FOR THE
PLAINS. IT WILL BE BREEZY WEST OF THE LARAMIE RANGE WITH SOUTHWEST
WINDS GUSTING TO NEAR 25 MPH.
HIGH TEMPERATURES SUNDAY AND MONDAY WILL BE 3-5 DEGREES WARMER
WITH 700MB TEMPERATURES PEAKING 16-17C. 90S WILL PREVAIL EAST
OF THE LARAMIE RANGE BOTH DAYS. MONDAY AFTERNOON WILL BE WARMEST
OF THE TWO DAYS...WITH A FEW LOCATIONS IN THE WESTERN NE PANHANDLE
TOPPING OUT AT 100 DEGREES. LOW LEVEL THERMAL/INSTABILITY AXIS
WILL RESIDE EAST OF THE CWA...HOWEVER WITH THE POSITION OF THE
RIGHT REAR QUADRANT OF THE UPPER JET OVERHEAD...CANNOT RULE OUT
A FEW AFTERNOON/EARLY EVENING TSTORMS FOR THE HIGH PLAINS SUNDAY
AND MONDAY. THE PRESSURE GRADIENT AND INCREASING SOUTHWEST FLOW
ALOFT AHEAD OF AN APPROACHING TROUGH AND COLD FRONT MONDAY WILL
INDUCE WINDY CONDITIONS WEST OF THE LARAMIE RANGE WITH GUSTS
POSSIBLY EXCEEDING 40 MPH.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 230 AM MDT SAT JUL 25 2015
WEATHER CONDITIONS WILL REMAIN ON THE DRIER SIDE THROUGH THE
LONGER TERM FORECAST PERIOD. MONDAY NIGHT STARTS OFF WITH AN
UPPER LEVEL TROUGH OVER THE NORTHERN ROCKIES. DEPENDING ON THE
EXACT TRACK OF THE UPPER LEVEL LOW COULD SEE A FEW THUNDERSTORMS
OVER FAR NORTHERN AND/OR EASTERN PORTIONS OF THE FORECAST AREA
MONDAY EVENING. CURRENTLY THE GFS AND ECMWF KEEP THE MAIN ENERGY
NORTH OF THE FORECAST AREA.
A REINFORCING PUSH OF COOLER AIR EXPECTED TUESDAY AS THE MAIN
UPPER LEVEL TROUGH PUSHES EAST INTO THE PLAINS. TIMING OF THE COOL
PUSH SHOULD KEEP CHANCES FOR PRECIPITATION AT A MINIMUM OVER THE
FORECAST AREA WITH THUNDERSTORM ACTIVITY LIKELY DEVELOPING WELL
EAST INTO CENTRAL NEBRASKA AND SOUTH INTO COLORADO. HIGH
TEMPERATURES TUESDAY SHOULD RANGE FROM THE LOWER 70S WEST TO
LOW-MID 80S INTO THE PLAINS.
MILD TEMPERATURES SHOULD CONTINUE WEDNESDAY WITH SOUTHEAST LOW
LEVEL FLOW IN PLACE OVER THE PLAINS. WEDNESDAY ALSO LOOKS TO BE ON
THE DRY SIDE WITH VERY MINIMAL CHANCES FOR PRECIPITATION...
ESPECIALLY WITH THE FORECAST AREA UNDER THE SUBSIDENCE SIDE OF THE
REAR UPPER LEVEL JET. ALSO LOOKING AT WESTERLY FLOW ALOFT
DEVELOPING WITH ZONAL FLOW IN PLACE OVER THE WESTERN CONUS.
WARMING TREND FOR LATTER PORTIONS OF NEXT WEEK WITH RIDGING OVER
THE WESTERN CONUS AND WEST TO NORTHWEST FLOW OVER THE FORECAST
AREA. HIGH TEMPERATURES SHOULD WARM INTO THE LOW 80S WEST TO
AROUND 90 INTO THE PLAINS THURSDAY AND SLIGHTLY WARMER FRIDAY.
EXPECTING VERY ISOLATED AFTERNOON THUNDERSTORMS ACTIVITY BUT
OVERALL CHANCES FOR WETTING RAIN WILL BE VERY LOW WITH
THUNDERSTORM COVERAGE LIKELY LESS THAN 10 PERCENT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 540 AM MDT SAT JUL 25 2015
VFR EXPECTED ACROSS SOUTHEAST WYOMING AND THE WESTERN NEBRASKA
PANHANDLE THROUGH THE TAF PERIOD. THE ONLY EXCEPTION BEING WITH
A FEW ISOLATED THUNDERSTORMS WHICH MAY DEVELOP LATE THIS AFTERNOON
INTO THE EARLY EVENING. WINDS WILL BECOME A BIT GUSTY LATE THIS
MORNING THROUGH THE AFTERNOON WITH GUSTS TO 15 KTS ACROSS THE
PLAINS AND GUSTS TO 25 KNOTS WEST OF THE LARAMIE RANGE.
&&
.FIRE WEATHER...
ISSUED AT 222 AM MDT SAT JUL 25 2015
WARM AND MAINLY DRY CONDITIONS WILL CONTINUE FOR THE DISTRICTS
THROUGH MONDAY BEFORE THE PASSAGE OF A COLD FRONT TUESDAY. NEAR-
CRITICAL WINDS AND HUMIDITIES FOR PORTIONS OF EAST CENTRAL AND
SOUTH CENTRAL WYOMING CAN BE EXPECTED THIS WEEKEND. THE BEST
CHANCE FOR WIDESPREAD CRITICAL FIRE WEATHER CONDITIONS WILL BEGIN
MONDAY MORNING AS WINDS ALOFT INCREASE FOLLOWING POOR OVERNIGHT
HUMIDITY RECOVERIES. SOUTHWEST WINDS MAY GUST OVER 40 MPH WEST OF
THE LARAMIE RANGE MONDAY WITH AFTERNOON HUMIDITIES FALLING INTO
THE SINGLE DIGITS TO LOW TEENS PERCENT. COOLER TEMPERATURES AND
SLIGHTLY HIGHER HUMIDITIES WILL PREVAIL TUESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...MAJ
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...MAJ
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
446 PM MDT SAT JUL 25 2015
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 312 PM MDT SAT JUL 25 2015
ATYPICAL JULY AFTERNOON IN A COUPLE OF WAYS...NO CONVECTIVE STORMS
AS OF 19Z. HRRR AND RAP INDICATE THAT A STORM OR TWO WILL POP OVER
THE SAN JUANS LATER THIS AFTERNOON AND PROMPTLY MOVE EAST.
CONVECTIVE ACTIVITY HAS DOMINATED THIS JULY...SO THE LACK OF
STORMS SEEMS OUT OF PLACE. ABUNDANT SUNSHINE PREVAILS TODAY BUT
HARDLY A SCORCHER. OUTSIDE OF MONUMENT VALLEY...NO TEMP SENSOR
HAVE REACHED 90F BY 1 PM. THE DRY SOUTHWEST FLOW WITH HIGH
PRESSURE CENTERED OVER THE SRN PLAINS HAS PROVIDED OUR FORECAST
AREA WITH A COMFORTABLE AND QUIET SUMMER DAY.
MOISTURE INCREASES FROM THE SOUTH EARLY SUNDAY MORNING RESULTING
IN CLOUD COVER INCREASING ACROSS SOUTHWEST COLORADO. SHOWERS ARE
EXPECTED TO BEGIN DEVELOPING BY NOON AND INCREASE IN COVERAGE AND
INTENSITY THROUGHOUT THE DAY SUNDAY AS 500 MB VORTICITY STREAMS
SOUTHWEST TO NORTHEAST ACROSS AN AREA FAIRLY SIMILAR TO YESTERDAY
BUT THE MOISTURE SHIELD REACHING FURTHER NORTH. THIS PLUME OF
MOISTURE LOOKS TO MOVE OFF TO THE EAST AND DISSIPATE ON SUNDAY
EVENING AS DRIER AIR PROTRUDES INTO WESTERN COLORADO FROM THE
GREAT BASIN. NORTHWEST COLORADO AND NORTHEAST UTAH WILL REMAIN DRY
AND BREEZY WITH THE ACTIVITY TO THE SOUTH AND A 60 KT JET
OVERHEAD.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 312 PM MDT SAT JUL 25 2015
A BURLY PACIFIC NORTHWEST TROUGH WILL PUSH EAST ACROSS THE
INTERMOUNTAIN WEST BEGINNING ON MONDAY AND BRUSH ALONG THE
WY/UT/CO BORDER MONDAY EVENING INTO TUESDAY. WINDS AHEAD OF THE
TROUGH ON MONDAY WILL BE ENHANCED WITH VERY GUSTY WINDS ALONG THE
NORTHERN UT/CO BOUNDARIES THANKS TO THE INCREASE PRESSURE GRADIENT
AND A 60 KT JET ALOFT. ASSUMING RELATIVE HUMIDITY VALUES CAN DRY
OUT ENOUGH IN THE AFTERNOON AS FORECAST MODELS HAVE BEEN SHOWING
FOR DAYS...WINDY AND DRY CONDITIONS DO LOOK PROBABLE IN NE UTAH
AND NW COLORADO. MOISTURE ON MONDAY WILL HUG THE SAN JUANS AND
SOUTHERN COLORADO DIVIDE MOUNTAINS SO SHOWERS AND A FEW ISOLATED
TSTORMS ARE POSSIBLE IN THESE AREAS.
THE NAM IS BRINGING A SOLID ELONGATED VORT MAX TO THE WY/UT/CO
BORDER ON TUESDAY LINED UP WITH THE ULJ WHILE THE GFS AND EC ARE
KEEPING THIS ENERGY A BIT FURTHER NORTH. THIS ENERGY STAYS IN
WYOMING BUT MAY KEEP CONDITIONS BREEZY ALONG THE WY/UT/CO BORDER.
500 MB HIGH PRESSURE BEGINS TO BACK TO THE WEST OVER THE FOUR
CORNERS LATER IN THE DAY ON TUESDAY. THIS HIGH PRESSURE WILL BE
CENTERED OVER THE SOUTHWEST AND GREAT BASIN BY THURSDAY AND
THROUGH SATURDAY. 700 MB ISOBARS SHOW CENTER OF HIGH PRESSURE AT
THAT LEVEL OVER WESTERN KS...WESTERN OK...AND THE PANHANDLE OF TX
WHICH WOULD STREAM MOISTURE INTO THE FOUR CORNERS FROM THE GULF.
SIGNAL LOOKS SLIGHTLY MONSOONAL AT THE END OF NEXT WEEK AS THIS
HIGH PRESSURE PATTERN SETS UP.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 446 PM MDT SAT JUL 25 2015
VFR CONDITIONS WILL REMAIN AT THE MAJORITY OF TAF SITES WITH
MOSTLY SUNNY SKIES AND BREEZY CONDITIONS TODAY. ISOLATED
-TSRA/-SHRA ARE EXPECTED OVER THE SAN JUAN MOUNTAINS THROUGH 03Z
AND HAVE A 10 PERCENT CHANCE OF AFFECTING KTEX. MOISTURE AND
SHOWERS/STORMS INCREASE FROM THE SOUTH LATE SUNDAY MORNING INTO
THE AFTERNOON WITH AREAS MAINLY SOUTH OF I-70 BEING AFFECTED.
&&
.FIRE WEATHER...
ISSUED AT 312 PM MDT SAT JUL 25 2015
RED FLAG WARNING IN EFFECT FOR FIRE ZONE 200 NOW UNTIL 8PM DUE TO
BREEZY AND DRY CONDITIONS CONTINUING THERE TODAY. WINDS WILL ERODE
THIS EVENING.
ISSUED FIRE WEATHER WATCH FOR SUNDAY FOR FIRE ZONE 200 WITH 60 KT
UPPER LEVEL JET SUPPORT IN PLACE AND DRY AIR REMAINING OVER NE
UTAH AND NW COLORADO WHILE MAINLY STRATIFORM RAIN IS EXPECTED IN
WEST CENTRAL AND SOUTHWEST COLORADO WITH SOME CONVECTIVE ELEMENT
IN THE AFTERNOON. ALREADY GUSTY WINDS MAY BE ENHANCED BY OUTFLOW
ORIGINATING FROM WELL SOUTH OF MOFFAT COUNTY. ALSO ISSUED A WATCH
FOR MONDAY FOR FIRE ZONES 200 201 202 AND 203 AFTER GOOD RUN TO
RUN CONSISTENCIES ON FORECAST WINDS AND LOW RH FOR MONDAY AS A
TROUGH BRUSHES BY THE WY/UT/CO BORDER. ON MONDAY CERTAIN PARTS OF
THE WATCH AREA MAY POTENTIALLY BE BATTLING WITH TOO MUCH MOISTURE
FROM SUNDAYS SHOWERS BUT FORECAST MODELS HAVE BEEN CONSISTENT ON
QUITE BREEZY CONDITIONS AND THIS SHOULD DRY CONDITIONS OUT PRETTY
QUICKLY. SINCE ITS JUST A WATCH DECIDED TO ERR ON THE SIDE OF
CAUTION WITH SUCH A DEFINED FEATURE AFFECTING THE AREA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FIRE WEATHER WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING
FOR COZ200>203.
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ200.
FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING
FOR COZ200.
UT...NONE.
&&
$$
SHORT TERM...PF/JAM
LONG TERM...JAM
AVIATION...MDA
FIRE WEATHER...JAM
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND JUNCTION CO
313 PM MDT SAT JUL 25 2015
CORRECTED ERROR IN FIRE WX SECTION
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 312 PM MDT SAT JUL 25 2015
ATYPICAL JULY AFTERNOON IN A COUPLE OF WAYS...NO CONVECTIVE STORMS
AS OF 19Z. HRRR AND RAP INDICATE THAT A STORM OR TWO WILL POP OVER
THE SAN JUANS LATER THIS AFTERNOON AND PROMPTLY MOVE EAST.
CONVECTIVE ACTIVITY HAS DOMINATED THIS JULY...SO THE LACK OF
STORMS SEEMS OUT OF PLACE. ABUNDANT SUNSHINE PREVAILS TODAY BUT
HARDLY A SCORCHER. OUTSIDE OF MONUMENT VALLEY...NO TEMP SENSOR
HAVE REACHED 90F BY 1 PM. THE DRY SOUTHWEST FLOW WITH HIGH
PRESSURE CENTERED OVER THE SRN PLAINS HAS PROVIDED OUR FORECAST
AREA WITH A COMFORTABLE AND QUIET SUMMER DAY.
MOISTURE INCREASES FROM THE SOUTH EARLY SUNDAY MORNING RESULTING
IN CLOUD COVER INCREASING ACROSS SOUTHWEST COLORADO. SHOWERS ARE
EXPECTED TO BEGIN DEVELOPING BY NOON AND INCREASE IN COVERAGE AND
INTENSITY THROUGHOUT THE DAY SUNDAY AS 500 MB VORTICITY STREAMS
SOUTHWEST TO NORTHEAST ACROSS AN AREA FAIRLY SIMILAR TO YESTERDAY
BUT THE MOISTURE SHIELD REACHING FURTHER NORTH. THIS PLUME OF
MOISTURE LOOKS TO MOVE OFF TO THE EAST AND DISSIPATE ON SUNDAY
EVENING AS DRIER AIR PROTRUDES INTO WESTERN COLORADO FROM THE
GREAT BASIN. NORTHWEST COLORADO AND NORTHEAST UTAH WILL REMAIN DRY
AND BREEZY WITH THE ACTIVITY TO THE SOUTH AND A 60 KT JET
OVERHEAD.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 312 PM MDT SAT JUL 25 2015
A BURLY PACIFIC NORTHWEST TROUGH WILL PUSH EAST ACROSS THE
INTERMOUNTAIN WEST BEGINNING ON MONDAY AND BRUSH ALONG THE
WY/UT/CO BORDER MONDAY EVENING INTO TUESDAY. WINDS AHEAD OF THE
TROUGH ON MONDAY WILL BE ENHANCED WITH VERY GUSTY WINDS ALONG THE
NORTHERN UT/CO BOUNDARIES THANKS TO THE INCREASE PRESSURE GRADIENT
AND A 60 KT JET ALOFT. ASSUMING RELATIVE HUMIDITY VALUES CAN DRY
OUT ENOUGH IN THE AFTERNOON AS FORECAST MODELS HAVE BEEN SHOWING
FOR DAYS...WINDY AND DRY CONDITIONS DO LOOK PROBABLE IN NE UTAH
AND NW COLORADO. MOISTURE ON MONDAY WILL HUG THE SAN JUANS AND
SOUTHERN COLORADO DIVIDE MOUNTAINS SO SHOWERS AND A FEW ISOLATED
TSTORMS ARE POSSIBLE IN THESE AREAS.
THE NAM IS BRINGING A SOLID ELONGATED VORT MAX TO THE WY/UT/CO
BORDER ON TUESDAY LINED UP WITH THE ULJ WHILE THE GFS AND EC ARE
KEEPING THIS ENERGY A BIT FURTHER NORTH. THIS ENERGY STAYS IN
WYOMING BUT MAY KEEP CONDITIONS BREEZY ALONG THE WY/UT/CO BORDER.
500 MB HIGH PRESSURE BEGINS TO BACK TO THE WEST OVER THE FOUR
CORNERS LATER IN THE DAY ON TUESDAY. THIS HIGH PRESSURE WILL BE
CENTERED OVER THE SOUTHWEST AND GREAT BASIN BY THURSDAY AND
THROUGH SATURDAY. 700 MB ISOBARS SHOW CENTER OF HIGH PRESSURE AT
THAT LEVEL OVER WESTERN KS...WESTERN OK...AND THE PANHANDLE OF TX
WHICH WOULD STREAM MOISTURE INTO THE FOUR CORNERS FROM THE GULF.
SIGNAL LOOKS SLIGHTLY MONSOONAL AT THE END OF NEXT WEEK AS THIS
HIGH PRESSURE PATTERN SETS UP.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1125 AM MDT SAT JUL 25 2015
ISOLATED -TSRA/-SHRA WILL DEVELOP OVER THE SWRN COLORADO MOUNTAINS
THIS AFTERNOON BETWEEN 20Z-01Z. ANY STORMS WILL BE SHORT LIVED AND
MOVE EASTWARD. OTHERWISE NO WEATHER RELATED AVIATION HAZARDS ARE
EXPECTED THROUGH THE FORECAST PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 312 PM MDT SAT JUL 25 2015
RED FLAG WARNING IN EFFECT FOR FIRE ZONE 200 NOW UNTIL 8PM DUE TO
BREEZY AND DRY CONDITIONS CONTINUING THERE TODAY. WINDS WILL ERODE
THIS EVENING.
ISSUED FIRE WEATHER WATCH FOR SUNDAY FOR FIRE ZONE 200 WITH 60 KT
UPPER LEVEL JET SUPPORT IN PLACE AND DRY AIR REMAINING OVER NE
UTAH AND NW COLORADO WHILE MAINLY STRATIFORM RAIN IS EXPECTED IN
WEST CENTRAL AND SOUTHWEST COLORADO WITH SOME CONVECTIVE ELEMENT
IN THE AFTERNOON. ALREADY GUSTY WINDS MAY BE ENHANCED BY OUTFLOW
ORIGINATING FROM WELL SOUTH OF MOFFAT COUNTY. ALSO ISSUED A WATCH
FOR MONDAY FOR FIRE ZONES 200 201 202 AND 203 AFTER GOOD RUN TO
RUN CONSISTENCIES ON FORECAST WINDS AND LOW RH FOR MONDAY AS A
TROUGH BRUSHES BY THE WY/UT/CO BORDER. ON MONDAY CERTAIN PARTS OF
THE WATCH AREA MAY POTENTIALLY BE BATTLING WITH TOO MUCH MOISTURE
FROM SUNDAYS SHOWERS BUT FORECAST MODELS HAVE BEEN CONSISTENT ON
QUITE BREEZY CONDITIONS AND THIS SHOULD DRY CONDITIONS OUT PRETTY
QUICKLY. SINCE ITS JUST A WATCH DECIDED TO ERR ON THE SIDE OF
CAUTION WITH SUCH A DEFINED FEATURE AFFECTING THE AREA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FIRE WEATHER WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING
FOR COZ200>203.
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ200.
FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING
FOR COZ200.
UT...NONE.
&&
$$
SHORT TERM...PF/JAM
LONG TERM...JAM
AVIATION...PF
FIRE WEATHER...JAM
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
308 PM MDT SAT JUL 25 2015
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 308 PM MDT SAT JUL 25 2015
ATYPICAL JULY AFTERNOON IN A COUPLE OF WAYS...NO CONVECTIVE STORMS
AS OF 19Z. HRRR AND RAP INDICATE THAT A STORM OR TWO WILL POP OVER
THE SAN JUANS LATER THIS AFTERNOON AND PROMPTLY MOVE EAST.
CONVECTIVE ACTIVITY HAS DOMINATED THIS JULY...SO THE LACK OF
STORMS SEEMS OUT OF PLACE. ABUNDANT SUNSHINE PREVAILS TODAY BUT
HARDLY A SCORCHER. OUTSIDE OF MONUMENT VALLEY...NO TEMP SENSOR
HAVE REACHED 90F BY 1 PM. THE DRY SOUTHWEST FLOW WITH HIGH
PRESSURE CENTERED OVER THE SRN PLAINS HAS PROVIDED OUR FORECAST
AREA WITH A COMFORTABLE AND QUIET SUMMER DAY.
MOISTURE INCREASES FROM THE SOUTH EARLY SUNDAY MORNING RESULTING
IN CLOUD COVER INCREASING ACROSS SOUTHWEST COLORADO. SHOWERS ARE
EXPECTED TO BEGIN DEVELOPING BY THE LATE MORNING AND INCREASE IN
COVERAGE AND INTENSITY THROUGHOUT THE DAY SUNDAY AS 500 MB
VORTICITY STREAMS SOUTHWEST TO NORTHEAST ACROSS AN AREA FAIRLY
SIMILAR TO YESTERDAY BUT THE MOISTURE SHIELD IS EXPECTED TO REACH FURTHER
NORTH. THIS PLUME OF MOISTURE LOOKS TO MOVE OFF TO THE EAST AND
DISSIPATE ON SUNDAY EVENING AS DRIER AIR PROTRUDES INTO WESTERN
COLORADO FROM THE GREAT BASIN. NORTHWEST COLORADO AND NORTHEAST
UTAH WILL REMAIN DRY AND BREEZY WITH THE ACTIVITY TO THE SOUTH AND
A 60 KT JET OVERHEAD.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 PM MDT SAT JUL 25 2015
A BURLY PACIFIC NORTHWEST TROUGH WILL PUSH EAST ACROSS THE
INTERMOUNTAIN WEST BEGINNING ON MONDAY AND BRUSH ALONG THE
WY/UT/CO BORDER MONDAY EVENING INTO TUESDAY. WINDS AHEAD OF THE
TROUGH ON MONDAY WILL BE ENHANCED WITH VERY GUSTY WINDS ALONG THE
NORTHERN UT/CO BOUNDARIES THANKS TO THE INCREASE PRESSURE GRADIENT
AND A 60 KT JET ALOFT. ASSUMING RELATIVE HUMIDITY VALUES CAN DRY
OUT ENOUGH IN THE AFTERNOON AS FORECAST MODELS HAVE BEEN SHOWING
FOR DAYS...WINDY AND DRY CONDITIONS DO LOOK PROBABLE IN NE UTAH
AND NW COLORADO. MOISTURE ON MONDAY WILL HUG THE SAN JUANS AND
SOUTHERN COLORADO DIVIDE MOUNTAINS SO SHOWERS AND A FEW ISOLATED
TSTORMS ARE POSSIBLE IN THESE AREAS.
THE NAM IS BRINGING A SOLID ELONGATED VORT MAX TO THE WY/UT/CO
BORDER ON TUESDAY LINED UP WITH THE ULJ WHILE THE GFS AND EC ARE
KEEPING THIS ENERGY A BIT FURTHER NORTH. THIS ENERGY STAYS IN
WYOMING BUT MAY KEEP CONDITIONS BREEZY ALONG THE WY/UT/CO BORDER.
500 MB HIGH PRESSURE BEGINS TO BACK TO THE WEST OVER THE FOUR
CORNERS LATER IN THE DAY ON TUESDAY. THIS HIGH PRESSURE WILL BE
CENTERED OVER THE SOUTHWEST AND GREAT BASIN BY THURSDAY AND
THROUGH SATURDAY. 700 MB ISOBARS SHOW CENTER OF HIGH PRESSURE AT
THAT LEVEL OVER WESTERN KS...WESTERN OK...AND THE PANHANDLE OF TX
WHICH WOULD STREAM MOISTURE INTO THE FOUR CORNERS FROM THE GULF.
SIGNAL LOOKS SLIGHTLY MONSOONAL AT THE END OF NEXT WEEK AS THIS
HIGH PRESSURE PATTERN SETS UP AND 6 TO 8 G/KG SPECIFIC HUMIDITY
IS PROGGED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1125 AM MDT SAT JUL 25 2015
ISOLATED -TSRA/-SHRA WILL DEVELOP OVER THE SWRN COLORADO MOUNTAINS
THIS AFTERNOON BETWEEN 20Z-01Z. ANY STORMS WILL BE SHORT LIVED AND
MOVE EASTWARD. OTHERWISE NO WEATHER RELATED AVIATION HAZARDS ARE
EXPECTED THROUGH THE FORECAST PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 308 PM MDT SAT JUL 25 2015
RED FLAG WARNING IN EFFECT FOR FIRE ZONE 200 NOW UNTIL 8PM DUE TO
BREEZY AND DRY CONDITIONS CONTINUING THERE TODAY. WINDS WILL ERODE
THIS EVENING.
ISSUED AT 304 PM MDT SAT JUL 25 2015
LEVEL JET SUPPORT IN PLACE AND DRY AIR REMAINING OVER NE UTAH AND
NW COLORADO WHILE MAINLY STRATIFORM RAIN IS EXPECTED IN WEST
CENTRAL AND SOUTHWEST COLORADO WITH SOME CONVECTIVE ELEMENT IN THE
AFTERNOON. ALREADY GUSTY WINDS MAY BE ENHANCED BY OUTFLOW
ORIGINATING FROM WELL SOUTH OF MOFFAT COUNTY. ALSO ISSUED A WATCH
FOR MONDAY FOR FIRE ZONES 200 201 202 AND 203 AFTER GOOD RUN TO
RUN CONSISTENCIES ON FORECAST WINDS AND LOW RH FOR MONDAY AS A
TROUGH BRUSHES BY THE WY/UT/CO BORDER. ON MONDAY CERTAIN PARTS OF THE
WATCH AREA MAY POTENTIALLY BE BATTLING WITH TOO MUCH MOISTURE FROM
SUNDAYS SHOWERS BUT FORECAST MODELS HAVE BEEN CONSISTENT ON QUITE
BREEZY CONDITIONS AND THIS SHOULD DRY CONDITIONS OUT PRETTY
QUICKLY. SINCE ITS JUST A WATCH DECIDED TO ERR ON THE SIDE OF
CAUTION WITH SUCH A DEFINED FEATURE AFFECTING THE AREA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FIRE WEATHER WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING
FOR COZ200>203.
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ200.
FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING
FOR COZ200.
UT...NONE.
&&
$$
SHORT TERM...PF/JAM
LONG TERM...JAM
AVIATION...PF
FIRE WEATHER...JAM
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1125 AM MDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 1125 AM MDT SAT JUL 25 2015
HIGHER RESOLUTION MODELS SUCH AS THE HRRR NOT VERY EXCITED ABOUT
CONVECTIVE POTENTIAL THIS AFTERNOON. HRRR SHOWS ISOLATED ACTION
OVER THE ERN SAN JUAN MOUNTAINS...BUT QUIET ELSEWHERE. WATER VAPOR
SHOWS MOISTURE PLUME CUTS ACROSS THE SW COLORADO CORNER BUT
MOISTURE TRANSPORT IS WEAK. GOES SOUNDER SHOW STABLE LIFTED
INDICES ACROSS THE WESTERN SLOPE AND ERN UTAH...SUPPORTING THE
RAP/HRRR MODELS OF MINIMAL CONVECTIVE ACTIVITY THIS AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 418 AM MDT SAT JUL 25 2015
CONDITIONS WILL BE MUCH DRIER TODAY AS A SHORTWAVE DISTURBANCE
MOVING ACROSS THE NORTHERN GREAT BASIN AND NORTHERN ROCKIES HELPS
PUSH THE MOISTURE PLUME THAT WAS OVER PORTIONS OF SOUTHWEST AND WEST-
CENTRAL COLORADO YESTERDAY FURTHER TO THE EAST-SOUTHEAST WITH THE
FLOW SHIFTING TO MORE OF A WESTERLY DIRECTION. PRECIPITABLE WATER
(PW) VALUES ARE FORECASTED TO BE LESS THAN 0.5 INCHES ACROSS MUCH OF
THE AREA WHICH SHOULD TRANSLATE TO MUCH LESS CLOUDS AND STORMS. THE
BEST MOISTURE WILL RESIDE ACROSS SOUTHERN PORTIONS OF THE FORECAST
AREA WITH THE BEST CHANCES OF SHOWERS AND STORMS OVER THE SAN JUANS
AND MAYBE WEST ELKS. OTHERWISE A MUCH DRIER DAY. BREEZY CONDITIONS
MAY OCCUR AT TIMES WITH GUSTS OF 15 TO 25 MPH ACROSS PORTIONS OF NE
UTAH AND NW COLORADO AS THE JET REMAINS OVERHEAD WITH A VORT MAX
MOVING THROUGH LATE THIS AFTERNOON. CONDITIONS WILL BE MARGINAL FOR
RED FLAG CRITERIA AND DO NOT APPEAR TO WARRANT ANY FIRE WEATHER
HIGHLIGHTS AT THIS TIME BUT SHOULD BE MONITORED.
AN AREA OF LOW PRESSURE OVER THE PACIFIC NW WILL BEGIN TO CARVE A
TROUGH OVER THE WESTERN U.S. ON SUNDAY. THIS WILL SHIFT THE WINDS
BACK TO THE SOUTHWEST...ALLOWING MONSOONAL MOISTURE TO SURGE BACK
NORTHWARD OVER OUR CWA WITH THE HIGH PRESSURE STILL CENTERED NEAR
THE TEXAS-OKLAHOMA PANHANDLE REGION. PW VALUES INCREASE TO 0.75
INCHES AND GREATER SOUTH OF I-70 ON SUNDAY WITH NEAR AN INCH IN
SPOTS...MAINLY FOCUSED NEAR THE FOUR CORNERS AND SOUTHWEST COLORADO.
A SHORTWAVE DISTURBANCE WILL ROUND THE BASE OF THE TROUGH MOVING
THROUGH UTAH ON SUNDAY AS EVIDENT IN 5H WIND STREAMLINES AND 1.0 PVU
VORTICITY FIELDS...HELPING TO INCREASE STORM ACTIVITY. LEANED
TOWARDS THE GFS FOR THIS FORECAST AS THIS MODEL INITIALIZED MUCH
BETTER WITH YESTERDAYS PRECIPITATION THAN THE OTHER MODELS.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 418 AM MDT SAT JUL 25 2015
NOT MUCH DIFFERENCE IN THE LONGER TERM MODEL SOLUTIONS. THE BASIC
PATTERN STARTS OFF WITH HIGH PRESSURE CENTERED OVER OKLAHOMA AND
LOW PRESSURE ALONG THE PACNW AND BRITISH COLUMBIA COAST. THE LOW
OVER THE NW MOVES INLAND MONDAY AS THE HIGH PRESSURE IS PUSHED
EAST. THIS BRINGS A FAIRLY STRONG JET OVER NORTHERN NV AND UT AND
INTO SOUTHERN ID AND WESTERN WY MONDAY AFTERNOON. THE GRADIENT
TIGHTENS OVER NE UT AND THE NW AND WEST-CENTRAL CO MON AFTERNOON
AND EVENING. SURFACE WINDS MAY BECOME STRONG ENOUGH TO CAUSE FIRE
WEATHER CONCERNS. FORECAST TIME-HEIGHT GRAPHS AND FORECAST
SOUNDINGS SHOW 50-60 KTS OF SW WINDS AT 300 MB. 700 MB WINDS MONDAY
AFTERNOON ARE PREDICTED TO RANGE FROM 15-20 KTS IN THE GFS TO 25
KTS IN THE ECMWF. THE STRONGEST WINDS APPEAR TO REMAIN NW OF THE
FORECAST AREA. MONDAY WILL BE WATCHED CLOSELY FROM A FIRE WEATHER
STANDPOINT.
THE NW LOW WILL RIDE QUICKLY EAST ALONG THE CAN/U.S. BORDER AND
THE GRADIENT FLOW SHOULD DECREASE TUE. AS THE LOW REACHES THE
GREAT LAKES WED...THE HIGH SE OF THE AREA WILL SLIDE WEST OVER
THE FOUR CORNERS. BY THU THIS HIGH WILL BE CENTERED OVER SW UT AND
BUILD A LARGE RIDGE OVER THE WESTERN U.S. THIS SHOULD BE A
SIGNIFICANT PATTERN CHANGE THAT WILL REMAIN FOR SEVERAL DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1125 AM MDT SAT JUL 25 2015
ISOLATED -TSRA/-SHRA WILL DEVELOP OVER THE SWRN COLORADO MOUNTAINS
THIS AFTERNOON BETWEEN 20Z-01Z. ANY STORMS WILL BE SHORT LIVED AND
MOVE EASTWARD. OTHERWISE NO WEATHER RELATED AVIATION HAZARDS ARE
EXPECTED THROUGH THE FORECAST PERIOD.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...MDA
LONG TERM...CC
AVIATION...PF
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
406 PM EDT SAT JUL 25 2015
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THE FLORIDA PENINSULA
UNDER A SIGNIFICANT WEAKNESS IN THE UPPER LEVELS. A LARGE REGION
OF UPPER RIDGING REMAINS OFF TO OUR NORTHWEST...STILL SUPPLYING
OUR REGION WITH UPPER LEVEL NORTH TO NORTHEAST FLOW. WV IMAGERY
SHOWS A LARGE SWATH OF DRY MID/UPPER LEVEL AIR OVER THE SOUTHEAST
CONUS THAT HAS BEEN TRYING TO ADVECT SOUTHWARD WITH TIME. SOME OF
THIS AIR AS ARRIVED AS FAR SOUTH AS THE I-10 CORRIDOR...HOWEVER...
WE ARE STILL SEEING DEEP MOISTURE IN PLACE OVER CENTRAL AND
SOUTHERN PORTION OF THE FL PENINSULA. IT IS UNLIKELY THAT THIS
DEEPER MOISTURE WILL BE PUSHED MUCH FURTHER SOUTH FROM WHERE IT IS
LOCATED NOW.
CLOSER TO THE SURFACE...A QUASI-STATIONARY FRONTAL BOUNDARY CAN BE
ANALYZED ACROSS THE NORTH-CENTRAL FLORIDA PENINSULA...WHERE WINDS
SHIFT FROM A SOUTHWEST DIRECTION OVER MUCH OF THE STATE TO A
NORTHEAST DIRECTION ALONG I-10. LOOKING AT THE WIND AND SURFACE
PRESSURE OBSERVATIONS...ONE CAN IMAGINE A VERY WEAK AREA OF LOW
PRESSURE LOCATED SOMEWHERE OVER THE FLORIDA BIG BEND AREA...NEAR
CROSS CITY OR CHIEFLAND. REGIONAL RADARS SHOW THE HEAVY RAIN SEEN
OVER THE TAMPA BAY AREA/SOUTHERN NATURE COAST THROUGH MIDDAY TODAY
HAS SETTLED SOUTH ALONG THE SUNCOAST AND WEAKENED TO AN AREA OF
BROAD LIGHT/MODERATE RAIN. IN THE WAKE OF THIS EARLIER
CONVECTION...WAS ABLE TO GET SOME SUNNY BREAKS AND DECENT
INSOLATION TO THE NORTH OF I-4...AND NOW BEGINNING TO SEE MORE SCT
DIURNAL TYPE CONVECTION DEVELOPING. THIS IS NOT THE WIDESPREAD
RAINFALL SEEN IN THE PAST COUPLE DAYS...BUT ANY ADDITIONAL
DOWNPOURS WILL BE FALLING OVER SATURATED SOILS. FOR THIS REASON
WILL KEEP THE FLOOD WATCH UP ACROSS THE NORTHERN NATURE COAST
ZONES INTO THE EVENING...AND SEE HOW THESE SCT STORM EVOLVE. THE
FLOOD WATCH FROM PASCO SOUTHWARD ALONG THE COAST WILL CERTAINLY
NEED TO REMAIN UP THROUGH THE OVERNIGHT. WE CONTINUE TO GET
REPORTS OF STREET AND LOW LYING FLOODING IN FROM THESE AREAS...
EVEN THROUGH THE HEAVIER RAINFALL HAS TEMPORARILY ENDED. THERE
ARE GOOD INDICATIONS ALSO...THAT ADDITIONAL HEAVY RAINFALL WILL BE
RETURNING...ESPECIALLY ALONG THE COAST TO THE SOUTH OF TAMPA BAY
OVERNIGHT. MORE ON THIS POTENTIAL BELOW.
&&
.SHORT TERM...
WET TIMES CONTINUE ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA. AS
WE HEAD THROUGH THE OVERNIGHT...ENSEMBLE GUIDANCE IN AGREEMENT
THAT A WEAK AREA OF LOW PRESSURE OVER NORTH-CENTRAL FLORIDA WILL
SETTLE SOUTHWARD TO NEAR THE TAMPA BAY AREA...AND THEN STALL INTO
THE DAY ON SUNDAY.
SCT DIURNALLY DRIVEN SHOWERS WILL CONTINUE OVER THE NATURE COAST
ZONES THROUGH EARLY EVENING...AND THEN DIMINISH WITH THE LOSS OF
HEATING AFTER SUNSET. THE NORTHEAST FLOW ACROSS THESE NORTHERN
ZONES AROUND THE WEAK LOW CENTER SHOULD SUPPORT A MAINLY DRY
FORECAST NORTH OF I-4 THROUGH A GOOD PORTION OF THE OVERNIGHT. A
FEW WIDELY SCT SHOWERS CAN NEVER BE RULED OUT WITH THE ABUNDANT
LOW LEVEL MOISTURE/SOIL MOISTURE AND GENERAL ATMOSPHERIC
SPIN...HOWEVER SIGNIFICANT ADDITIONS TO THE ALREADY ACCUMULATED
RAIN IS NOT ANTICIPATED. THE FURTHER SOUTH FROM THE I-4 CORRIDOR
ONE TRAVELS TONIGHT...THE TRICKIER THE FORECAST GETS IN TERMS OF
HEAVY RAINFALL POTENTIAL. DEEP MOISTURE WILL REMAIN IN PLACE TO
THE SOUTH OF TAMPA BAY...AND THE SURFACE FRONT LYING ACROSS THE
EAST-CENTRAL GULF SETS UP A DECENT LOW LEVEL ZONE OF
FOCUS/CONVERGENCE OVER OUR SOUTHERN MARINE ZONES/SUNCOAST ZONES.
GENERAL MODEL CONSENSUS IS FOR ANOTHER CONVECTIVE BAND TO ORGANIZE
OVERNIGHT AND MOVE ASHORE INTO THE SUNCOAST...ALTHOUGH JUST HOW
FAR SOUTH IS A BIT IN QUESTION. RIGHT NOW...WOULD BE ADVISABLE TO
PLAN FOR HEAVY RAINFALL POTENTIAL ANYWHERE FROM MANATEE COUNTY
SOUTHWARD TO LEE COUNTY...ALTHOUGH THE BEST PROBABILITY OF
SIGNIFICANT RAINFALL WOULD LIKELY BE FROM CENTRAL SARASOTA COUNTY
DOWN ACROSS CHARLOTTE/LEE...AND MAINLY AFTER MIDNIGHT/EARLY SUNDAY
MORNING. THE NAM IS BY FAR THE MOST AGGRESSIVE WITH ITS
CONVERGENT BAND AND HAVE LEANED AWAY FROM THIS SOLUTION IN SUPPORT
OF SOMETHING CLOSER TO A SREF MEAN/ECMWF BLEND FOR THE HIGHEST
POPS AND HEAVIEST QPF TOTALS. ANYWHERE THIS BAND DOES DEVELOP
COULD EASILY SEE AN ADDITIONAL SEVERAL INCHES OF RAINFALL...
HOWEVER AREAL TOTALS WOULD MORE LIKELY BE IN THE 1-2" RANGE ALONG
THE SUNCOAST.
THE HEAVIEST AND MOST WIDESPREAD RAINFALL SUNDAY MORNING IS LIKELY
TO REMAIN OVER THE SOUTHERN THIRD OF THE FORECAST AREA...HOWEVER
WITH DIURNAL HEATING...SCT TO NUMEROUS CONVECTIVE DEVELOPMENT IS
ANTICIPATED ACROSS THE REMAINING ZONES. RAINFALL TENDS TO PROMOTE
RAINFALL...AND ADDING SATURATED SOILS AND DIURNAL HEATING
TOGETHER SHOULD PROMOTE PLENTY OF DEVELOPING SHOWERS THE SECOND
HALF OF THE DAY. CERTAINLY NOT EXPECTING THE TYPES OF RAINFALL
AMOUNTS ON SUNDAY AROUND THE TAMPA BAY AREA AND NATURE COAST THAT
HAVE BEEN SEEN RECENTLY...HOWEVER...WITH SOILS SATURATED OR NEARLY
SATURATED...EVEN LESS WIDESPREAD DOWNPOURS WILL LIKELY STILL CAUSE
FLOODING AGGRAVATION. BASED ON THE AMOUNTS OF RAINFALL SEEN
RECENTLY AROUND TAMPA BAY AND PASCO COUNTY...AND THE POTENTIAL FOR
MORE ORGANIZED HEAVY RAINFALL THROUGH SUNDAY MORNING SOUTH OF
TAMPA BAY...WILL LEAVE THE ONGOING FLOOD WATCH FROM PASCO TO LEE
COUNTY IN EFFECT THROUGH 18Z SUNDAY.
&&
.LONG TERM (SUNDAY NIGHT - FRIDAY)...
BY THE END OF THE WEEKEND...THE MID LEVEL TROUGH OVER CENTRAL
FLORIDA IS FORECAST TO BE WEAKENING SOMEWHAT...AS IT SLIPS INTO
SOUTHERN FLORIDA THROUGH THE FIRST HALF OF THE WORK WEEK. THE
SURFACE TROUGH THAT HAS BEEN HELPING TO PRODUCE THE HEAVY RAIN
DURING THE LAST COUPLE OF DAYS WILL BE WEAKER BY MONDAY...AND WILL
VERY SLOWLY SLIP SOUTH INTO SOUTHERN FLORIDA THROUGH THURSDAY WHILE
IT SLOWLY BREAKS DOWN. THIS WILL KEEP WEST/SOUTHWEST FLOW OVER THE
SOUTHERN PARTS OF THE FORECAST AREA...WITH LIGHTER NORTHEAST FLOW
OVER THE NORTHERN REGIONS. PRECIPITABLE WATER VALUES ARE FORECAST TO
STAY AROUND 2-2.25 INCHES...PARTICULARLY ALONG THE SOUTHERN EDGE OF
THE SURFACE TROUGH KEEPING CONDITIONS FAVORABLE FOR PERIODS OF HEAVY
DOWNPOURS...ALTHOUGH THE SETUP DOES NOT LOOK LIKELY TO PRODUCE THE
KIND OF FLOODING OCCURRING THIS WEEKEND. ALL TOLD...EXPECT
SCATTERED TO NUMEROUS THUNDERSTORMS EACH AFTERNOON...WITH THE
HIGHEST CHANCES GENERALLY FROM TAMPA BAY SOUTH. ON FRIDAY...THE
SURFACE SUBTROPICAL RIDGE AXIS WILL SETUP OVER THE BAHAMAS AND
INTO SOUTHERN FLORIDA...WITH ANOTHER SURFACE TROUGH PUSHING INTO
NORTH FLORIDA. AS A RESULT...SOUTHWESTERLY FLOW WILL RETURN...WITH
EARLY MORNING SHOWERS AND STORMS EXPECTED TO DEVELOP OVER THE
EASTERN GULF OF MEXICO...MOVING INTO THE COAST THROUGH THE MORNING
AND AFTERNOON.&&
.AVIATION...
THE HEAVIEST RAINFALL HAS ENDED FOR THE TIME BEING AND GENERALLY
LOOKING AT VFR CONDITIONS ACROSS THE TAF SITE FOR THE LATE
AFTERNOON AND EVENING HOURS. A FEW BRIEF PERIOD OF MVFR CIGS/VIS
ARE POSSIBLE WITH ANY CONVECTIVE ELEMENTS...BUT OTHERWISE JUST
EXPECTING LIGHTER RAINS FROM KPGD/KFMY/KRSW. LATER TONIGHT INTO
SUNDAY MORNING...ADDITIONAL POTENTIAL FOR HEAVY RAINFALL
DEVELOPS...ESPECIALLY FROM KSRQ SOUTHWARD.
&&
.MARINE...
AN AREA OF LOW PRESSURE CENTERED OFF THE CAROLINA
COASTLINE EXTENDS ACROSS NORTH FLORIDA INTO THE NORTHERN GULF.
THE ATTENDANT SURFACE BOUNDARY CONTINUES TO SLOWLY DRIFT SOUTH
HELPING TO MAINTAIN A VERY MOIST WESTERLY FLOW. NUMEROUS TO
WIDESPREAD SHOWERS WITH EMBEDDED THUNDERSTORMS EXPECTED TO
CONTINUE THROUGH THE END OF THE WEEKEND BUT WILL GRADUALLY
DIMINISH IN COVERAGE FROM NORTH TO SOUTH.
&&
.FIRE WEATHER...
A WEAK AREA OF LOW PRESSURE WILL REMAIN OVER CENTRAL OR NORTHERN
FLORIDA THROUGH THE EARLY PORTION OF THE WEEK. ABUNDANT LOW LEVEL
MOISTURE WILL KEEP RELATIVE HUMIDITY VALUES WELL ABOVE CRITICAL
LEVELS...AND NO SIGNIFICANT FIRE WEATHER CONCERNS ARE EXPECTED.
THE HEAVIEST RAINFALL POTENTIAL THROUGH SUNDAY WILL BE SOUTH OF
THE I-4 CORRIDOR...ALTHOUGH WETTING RAIN IS LIKELY OVER MUCH
OF THE FORECAST AREA.
FOG POTENTIAL...
NO SIGNIFICANT FOG OR VISIBILITY ISSUES ARE ANTICIPATED THROUGH
MONDAY.
&&
HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR PASCO...NORTHERN
HILLSBOROUGH AND PINELLAS COUNTIES UNTIL 2145Z. A FLOOD WATCH
CONTINUES TODAY FOR THE COASTAL COUNTIES OF WEST CENTRAL AND
SOUTHWEST FLORIDA UNTIL 26/00Z. AS THE FRONT SHIFTS SOUTHWARD... WE
WILL ALLOW THE FLOOD WATCH TO EXPIRE NORTH OF HERNANDO COUNTY AND
WILL KEEP THE WATCH VALID FOR THE COASTAL COUNTIES FROM PASCO COUNTY
SOUTHWARD THROUGH LEE COUNTY THROUGH SUNDAY AFTERNOON AT 26/18Z.
DEEP TROPICAL MOISTURE WILL REMAIN ACROSS THE REGION TODAY SOUTH OF
TAMPA BAY WITH PCPW VALUES IN EXCESS OF 2.00 INCHES...WITH TBW
REPORTING 2.13 INCHES ON THE 25/12Z SOUNDING. THE SURFACE TROUGH
WILL STALL ACROSS THE CENTRAL FLORIDA PENINSULA THIS AFTERNOON AND
THIS WILL PUSH THE THREAT FOR HEAVY RAIN TO THE SOUTH TONIGHT AND
SUNDAY...GENERALLY ALONG THE COAST FROM PASCO COUNTY SOUTH TO LEE
COUNTY WITH THE GREATEST THREAT FOR HEAVY RAIN OVER SOUTHWEST
FLORIDA. STRONGER DAYTIME HEATING MAY LEAD TO INCREASED CONVECTIVE
INSTABILITY ACROSS THE NATURE COAST AND PORTIONS OF WEST CENTRAL
FLORIDA SUNDAY AFTERNOON.
SOME OF THE HEAVIEST RAINFALL WAS OVER SOUTHWEST PASCO COUNTY AND
HAS CAUSED THE ANCLOTE RIVER AT ELFERS TO RISE ABOVE FLOOD STAGE.
THE RIVER IS EXPECTED TO CREST JUST BELOW 22 FEET EARLY SUNDAY
MORNING AND THEN BEGIN RECEDING AND EXPECTED TO DROP BELOW FLOOD
STAGE BY MONDAY MORNING. AS THE HEAVIEST RAINS SHIFT SOUTH...THE
MYAKKA RIVER AT MYAKKA RIVER STATE PARK AND LITTLE MANATEE RIVER AT
WIMAUMA IS EXPECTED TO GO ABOVE ACTION STAGE EARLY SUNDAY MORNING.
THESE RIVERS ARE NOT EXPECTED TO RISE ABOVE FLOOD STAGE AT THIS TIME
BUT WILL BE CLOSELY MONITORED FOR RUNOFF FROM HEAVY RAINS CAUSING
ANY FURTHER RISE IN THE WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 76 87 78 88 / 50 70 40 60
FMY 76 86 77 89 / 90 90 50 60
GIF 75 88 75 89 / 40 70 30 60
SRQ 76 86 78 88 / 60 70 60 70
BKV 74 89 75 89 / 40 70 30 60
SPG 77 87 78 88 / 50 70 50 70
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR COASTAL CITRUS-
COASTAL HERNANDO-COASTAL LEVY-INLAND CITRUS-INLAND
HERNANDO-INLAND LEVY.
HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
COASTAL CHARLOTTE-COASTAL HILLSBOROUGH-COASTAL LEE-
COASTAL MANATEE-COASTAL SARASOTA-PINELLAS.
FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR COASTAL CHARLOTTE-
COASTAL HILLSBOROUGH-COASTAL LEE-COASTAL MANATEE-
COASTAL PASCO-COASTAL SARASOTA-INLAND CHARLOTTE-
INLAND HILLSBOROUGH-INLAND LEE-INLAND MANATEE-INLAND
PASCO-INLAND SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/FIRE WEATHER...14/MROCZKA
LONG TERM/DECISION SUPPORT...FLEMING
HYDROLOGY...WYNN
MARINE...GARCIA
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
247 PM EDT SAT JUL 25 2015
...PASSING COASTAL SHOWERS AND ISOLATED TSTORMS...
.SHORT TERM...TODAY THROUGH TUE NIGHT...
TODAY THROUGH SUN...THE SURFACE COLD FRONT WAS EDGING SOUTH ACROSS
NE FL TRAILED BY NUMEROUS TINY SHOWERS BLOSSOMING ACROSS SE GA AND
NE FL...WITH THE ONLY TSTORM ACTIVITY THIS HOUR STILL WELL OFFSHORE
OF THE FL ATLANTIC COAST CLOSE TO A BROAD SURFACE LOW. BOTH THE NAM12
AND HRRR GUIDANCE HAVE INITIALIZED WELL WITH TODAYS PRECIP EVOLUTION
AS WELL AS THE STRENGTH OF THE HIGH PRESSURE WEDGE EDGING SOUTHWARD
DOWN THE SE GA COAST. THROUGH THE REMAINDER OF THE AFTERNOON NUMEROUS
SHOWERS TO CONTINUE TO PUSH WSW ACROSS THE INTERIOR WITH ISOLATED TSTORM
ACTIVITY INLAND AND OFFSHORE AS DRY AIR ALOFT WILL LIMIT DEPTH OF CONVECTION.
A FEW STRONG STORMS WILL BE CAPABLE OF WET DOWNBURSTS...WITH A CORRIDOR
OF HEAVY RAINFALL GENERALLY ALONG AND WEST OF A LAKE CITY TO
OCALA LINE WHERE BEST FOCUS OF LATE AFTN/EARLY EVENING LOW LEVEL
BOUNDARIES WILL CONVERGE. BREEZY ENE WINDS GUSTING NEAR 25 MPH AT
TIMES ALONG THE COAST WILL DECREASE THIS EVENING...WITH COASTAL
SHOWERS RESURRECTING AFTER MIDNIGHT ALONG THE FL ATLANTIC COAST.
COULD SEE SOME TRAINING CELLS WHICH COULD PRODUCE LOCALLY HEAVY
RAINFALL...BUT TOO EARLY TO TELL WHERE CONVERGENT BAND COULD
ESTABLISH THUS ADVERTISED 20-30% CHANCES AT THIS TIME. SUN MORNING
PRECIP WILL DRIFT INLAND WITH AGAIN A LOW CHANCE OF ISOLATED
TSTORMS BY EARLY AFTERNOON ACROSS INLAND NE FL. STACKED SUBSIDENCE
ACROSS SE GA SUN WILL LIMIT CONVECTIVE POTENTIAL AND ADVERTISED
POPS LESS THAN 15% WHILE TEMPS WILL RISE INTO THE LOW/MID 90S WITH
DEW PTS FALLING INTO THE MID/UPPER 60S NEAR THE ALTAMAHA RIVER
BASIN KEEPING HEAT INDICES GENERALLY BELOW 100 DEG. HIGHS ACROSS
NE FL WILL RANGE NEAR 90 TO UPPER 80S UNDER PASSING
SHOWERS/ISOLATED TSTORMS.
LOWS WILL FALL INTO THE LOWER 70S TONIGHT ACROSS SE GA TO THE MID 70S
ALONG THE COAST AND ST JOHNS RIVER BASIN. AREAS OF LATE NIGHT FOG WITH
PATCHY DENSE IS LIKELY ACROSS SE GA AND THE SUWANNEE RIVER VALLEY AFTER
MIDNIGHT WERE CLOUDS CAN CLEAR BEFORE LOW STRATUS FORMS.
SUNDAY NIGHT THROUGH TUESDAY NIGHT...FRONT WILL REMAIN STATIONARY ACROSS
CENTRAL FL WHILE A MID/UPPER RIDGE BUILDS ACROSS THE MISS VALLEY. DRIER
AIR AND NE TO E FLOW NORTH OF THE FRONT RESULTS IN LIMITED POPS ESPECIALLY
ACROSS SE GA...WHILE AREAS ACROSS THE FAR SOUTH WILL HAVE A CONTINUATION
OF MAINLY SCATTERED DIURNAL CONVECTION. TEMPS WARM TO ABOVE NORMAL ACROSS
INLAND SE GA WHERE READINGS THERE WILL BE IN THE MID 90S WITH HEAT INDICES
OF 102 TO 105 DEGREES. HIGHS ACROSS THE REST OF THE INTERIOR WILL GENERALLY
BE IN THE LOWER 90S WITH HEAT INDICES OF 100 TO 103 DEGREES. COOLEST
READINGS IN THE MID TO UPPER 80S WILL BE ALONG THE COAST DUE TO THE
ONSHORE FLOW.
.LONG TERM...WEDNESDAY THROUGH SATURDAY...
MODELS CONTINUE IN GENERAL AGREEMENT WITH THE MEAN LAYER RIDGE RETROGRADING
INTO THE WESTERN U.S. AND TROUGH REESTABLISHING ITSELF OVER THE EASTERN
CONUS. THE GFS ALSO DEVELOPS A WEAK CLOSED LOW IN THE NE GULF TOWARDS
THE END OF THE WEEK AND MOVES IT SLOWLY NORTHEAST INTO SE GA BY THE
FIRST PART OF NEXT WEEKEND. POPS...AS A RESULT...WILL BE INCREASING
AGAIN DURING THE WEEK. TEMPS WILL AVERAGE NEAR NORMAL ACROSS THE FL
PENINSULA BUT WILL REMAIN ABOVE NORMAL ACROSS INLAND SE GA.
&&
.AVIATION...MVFR CIGS ACROSS NE FL TERMINALS THIS AFTN WITH
PREVAILING VFR AT SSI. TS MOST PROBABLE AT GNV THIS AFTERNOON WITH
MVFR CIGS RAISING TO VFR ALONG THE FL COAST BY EVENING. AFTER
MIDNIGHT LOW STRATUS/SHALLOW GROUND FOG EXPECTED ACROSS INLAND
LOCATIONS AND SUGGESTED DEVELOPING MVFR CONDITIONS AT TERMINALS IN
THE 18Z PACKAGE. SHOWERS MOST LIKELY NEAR SGJ EARLY SUN MORNING
AND INCLUDED VCSH.
&&
.MARINE...A WEAK COLD FRONT WILL PUSH SOUTH OF THE WATERS TODAY THEN
STALL ACROSS CENTRAL FLORIDA THROUGH MID WEEK. THIS PATTERN WILL BRING
AN EXTENDED PERIOD OF LIGHT ONSHORE FLOW. WINDS REMAIN ELEVATED TRAILING
THE COLD FRONT OVER THE GA AND N FL LEGS THROUGH THIS EVENING AND WILL
ADVERTISED SMALL CRAFT EXERCISE CAUTION INITIALLY...DECREASING
BELOW HEADLINES AFTER MIDNIGHT.
RIP CURRENTS: MODERATE RISK TODAY AND SUNDAY DUE TO DEVELOPING
PERSISTENT EASTERLY FLOW.
&&
.HYDROLOGY...THE BLACK CREEK AT PENNY FARMS CONTINUED TO SLOWLY
RISE TO NEAR 8 FT THIS AFTERNOON AFTER YESTERDAYS 0.50" BASIN
AVERAGE RAINFALL...AND NOT MUCH QPF EXPECTED TODAY. RIVERS
INCLUDING THE OCKLAWAHA IN MARION WILL NEED TO BE MONITORED AS
THEY NEAR ACTION STAGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 70 94 70 95 / 10 10 10 20
SSI 76 86 77 86 / 10 10 10 20
JAX 74 89 72 91 / 20 20 20 20
SGJ 76 86 75 87 / 30 40 20 30
GNV 73 90 73 91 / 30 40 20 40
OCF 73 89 73 90 / 50 60 30 50
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
ENYEDI/PETERSON/WALSH
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
400 PM CDT SAT JUL 25 2015
.DISCUSSION...
TEMPS HAVE AGAIN REACHED THE UPPER 90S ACROSS ALL OF THE
REGION...WITH SHV REACHING 101 DEGREES /AS OF 2035Z/. THE LATEST
SFC ANALYSIS INDICATES THAT OUR WEAK SFC TROUGH HAS DRIFTED A TAD
S ACROSS SCNTRL AR INTO NE LA...WITH SCT CONVECTION BEGINNING TO
DEVELOP ALONG THIS BNDRY /AND ATTENDANT H850 THETA-E AXIS/ OVER SW
AND SCNTRL AR. VISIBLE SATELLITE IMAGERY ALSO INDICATES TOWERING
CU DEVELOP FARTHER SE INTO NE LA...WITH THE LATEST HRRR AND SSEO
ENSEMBLES SUGGESTING ADDITIONAL ISOLATED CONVECTION DEVELOPING
THROUGH LATE AFTERNOON/EVENING FARTHER W ACROSS NCNTRL LA.
MEANWHILE...THE WEAK STEERING WINDS ALOFT WOULD FAVOR THE
CONVECTION OVER SW AR DRIFTING SSW INTO EXTREME SE OK/SW AR...THUS
HAVE ADDED SLIGHT CHANCE POPS THIS EVENING OVER SE OK/SW AR/NCNTRL
LA. HOWEVER...THIS CONVECTION SHOULD WEAKEN LATER THIS EVENING
WITH THE LOSS OF HEATING...ALTHOUGH CAN/T RULE OUT A STRAY -SHRA
REDEVELOP LATE OVER NCNTRL LA NEAR THE SFC TROUGH AS HAS BEEN THE
CASE THE LAST COUPLE OF DAYS OVER CNTRL/ERN AR AND NCNTRL MS.
THE MAIN PLAYER THOUGH REMAINS THE DANGEROUS HEAT...WITH DEWPOINTS
FAILING TO MIX OUT MUCH AS HEAT INDICES HAVE RANGED FROM 105-110
OVER ALL OF THE CURRENT HEAT ADVISORY AREA THIS AFTERNOON. IN
FACT...INDICES AT RSN/MLU/BQP HAVE ALREADY REACHED 110 DEGREES
/THE UPPER END OF THE HEAT ADVISORY CRITERIA/. EXPECTING VERY
SIMILAR CONDITIONS SUNDAY AS TEMPS/DEWPOINTS WILL BE SIMILAR TO
WHAT WAS OBSERVED TODAY...THUS HAVE EXTENDED THE CURRENT HEAT
ADVISORY THROUGH 00Z MONDAY...WITH HIGH END CRITERIA AGAIN OVER
THE RSN/MLU AREAS ONCE AGAIN. THE CU FIELD MAY ACTUALLY REMAIN OR
REDEVELOP OVERNIGHT NEAR AND JUST W OF THE SFC TROUGH...WHICH
WOULD OFFER LITTLE RELIEF TO THE HEAT.
THE SHORT TERM PROGS DO DRIFT THE WEAK SFC TROUGH A LITTLE FARTHER
W SUNDAY INTO NCNTRL LA...WHICH WOULD FOCUS ISOLATED CONVECTION
DURING THE AFTERNOON OVER NCNTRL LA/LOWER TOLEDO BEND COUNTRY OF
DEEP E TX AROUND THE OUTER PERIPHERY OF THE UPPER RIDGE. DID
MAINTAIN MENTION OF SLIGHT CHANCE POPS SUNDAY EVENING FOR THESE
AREAS BEFORE HEATING IS LOST AFTER SUNSET. OTHERWISE...VERY HOT
AND DRY CONDITIONS LOOK TO PERSIST THROUGH MUCH OF NEXT WEEK AS
THE DEATH RIDGE BEGINS TO AMPLIFY AND SHIFT NE FROM THE SRN
PLAINS/LOWER MS VALLEY INTO THE MIDWEST MONDAY...LINGERING THROUGH
AT LEAST THURSDAY.
THE GFS HAS COME INTO BETTER AGREEMENT WITH THE ECMWF WITH A WEAK
UPPER TROUGH SLIDING SE AROUND THE RIDGE AS IT BEGINS TO
RETROGRADE W ACROSS THE RED RIVER VALLEY AND INTO THE FOUR CORNERS
REGION BY FRIDAY. THE PROGS DO MAINTAIN ISOLATED TO SCT
CONVECTION DEVELOPING THURSDAY AFTERNOON OVER MUCH OF THE
REGION...BEFORE DEEPENING NNERLY WINDS YIELD DRIER AIR ADVECTING
SSW INTO THE LOWER MS VALLEY/SRN PLAINS. THUS HAVE TAPERED SLIGHT
CHANCE POPS FROM N TO S FRIDAY...BEFORE SLIGHTLY COOLER TEMPS BUT
DRIER CONDITIONS RETURN FOR NEXT WEEKEND.
PRELIMS TO FOLLOW BELOW...
15
&&
.PREV DISCUSSION... /ISSUED 1159 AM CDT SAT JUL 25 2015/
AVIATION...
CU FIELD DEVELOPING TODAY WHERE WE WERE VOID OF CU DURING THE DAY
FRIDAY. UPPER LEVEL RIDGE CENTERED ACROSS THE TX HILL COUNTRY AND
IS FAR ENOUGH WEST THAT WE COULD SEE SOME ISOLATED TSRA ACROSS OUR
EASTERN TAF SITES LATER TODAY/THIS EVENING. STILL FEEL LIKE
COVERAGE IS NOT SIGNIFICANT ENOUGH TO WARRANT A MENTION IN THE 18Z
TAF PACKAGE HOWEVER. CONVECTION ACROSS SC AR THIS MORNING IS
ORIENTED ALONG A 700MB THETAE AXIS WHICH IS FCST TO BACKDOOR
ITSELF INTO SW AR AND N LA LATER TODAY.
OTHERWISE...VFR CONDITIONS SHOULD PREVAIL THROUGH THE NEXT 24
HOURS. WINDS WILL BE MOSTLY VARIABLE THROUGH THE TAF
PERIOD...MAINLY LESS THAN 10KTS.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 78 101 78 100 / 10 10 10 10
MLU 77 100 76 99 / 20 20 10 10
DEQ 73 98 74 99 / 20 10 10 10
TXK 76 100 77 100 / 20 10 10 10
ELD 76 99 76 99 / 20 20 10 10
TYR 78 100 78 99 / 0 0 0 10
GGG 78 101 78 100 / 0 10 0 10
LFK 75 98 75 98 / 0 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT SUNDAY FOR ARZ050-051-059>061-
070>073.
LA...HEAT ADVISORY UNTIL 7 PM CDT SUNDAY FOR LAZ001>006-010>014-
017>022.
OK...HEAT ADVISORY UNTIL 7 PM CDT SUNDAY FOR OKZ077.
TX...HEAT ADVISORY UNTIL 7 PM CDT SUNDAY FOR TXZ097-112-126-138-151.
&&
$$
15
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1239 PM CDT SAT JUL 25 2015
.UPDATE...
SURFACE DEWPOINTS ON THE MISSISSIPPI COAST AND AROUND LAKE
PONTCHARTRAIN HAVE REMAINED ELEVATED BETWEEN 75 AND
78F...RESULTING IN HEAT INDICES 105 TO 110 AT NOON. ERGO...ISSUED
A HEAT ADVISORY THROUGH 00Z. NORTHERLY FLOW ALOFT MEAN LATE
STORMS SO RELIEF WILL NOT BE PRESENT IN THE HEAT OF THE DAY.
&&
.PREV DISCUSSION... /ISSUED 750 AM CDT SAT JUL 25 2015/
..SOUNDING DISCUSSION...
AN ELEVATED TEMPERATURE INVERSION BEGINS AROUND 750 FEET AND GOES
UP TO 2000 FEET. 925 MB TEMPERATURE IS ALMOST 26C WITH THE 850MB
TEMPERATURE AT 19.5C...BOTH OF WHICH ARE RECORDS FOR THIS
DATE/TIME BASED OFF OF SPC SOUNDING CLIMATOLOGY. MOST OF THE
MOISTURE IN THE COLUMN IS BELOW 12000 FEET WITH A NEAR SATURATED
LAYER AROUND 9500 FEET. WHILE ABOVE THIS LAYER THERE IS NOT AS MUCH
MOISTURE...THE PRECIPITABLE WATER IN THE COLUMN IS AT 2.06 INCHES.
THE CONVECTIVE TEMPERATURE IS 94F...BUT GIVEN SUBSIDENCE OVERHEAD
WE SHOULD SEE LIMITED THUNDERSTORMS AGAIN TODAY. LATEST HRRR HAS
PROGGED WELL WITH SHOWERS OVER COASTAL MISSISSIPPI AND
THUNDERSTORMS SOUTH OF PASCAGOULA/MOBILE. IT POPS QUITE A FEW
SHOWERS AND THUNDERSTORMS AROUND MIDDAY. HOWEVER...IT`S COVERAGE
IS LIKELY OVERDONE DUE TO IT`S HIGHER FORECAST TEMPERATURES. WINDS
IN THE PROFILE ARE FROM THE NORTHWEST FROM THE SURFACE TO 17000
FEET...THEN SLOWLY ROTATE AROUND TO THE NORTH AND THEN FINALLY
NORTHEAST IN THE UPPER LEVELS. A PEAK WIND SPEED OF 28 KNOTS WAS
FOUND NEAR 1000 FEET.
12Z BALLOON INFO: THERE WERE NO ISSUES WITH THE FLIGHT THIS
MORNING. THE BALLOON REACHED A HEIGHT OF 19.6 MILES ABOVE THE
GROUND BURSTING OVER THE SOUTHWEST PART OF LAKE PONTCHARTRAIN 34
MILES DOWNRANGE FROM THE OFFICE. THE BALLOON ASCENDED FOR 100
MINUTES.
ANSORGE
PREV DISCUSSION... /ISSUED 351 AM CDT SAT JUL 25 2015/
DISCUSSION...
THE STRONG UPPER RIDGE CENTERED OVER THE SOUTHERN PLAINS THIS
MORNING WILL CONTINUE TO DOMINATE THE WEATHER ACROSS THE FORECAST
AREA FOR MUCH OF THE FORECAST PERIOD. THIS WILL MEAN THE CONTINUATION
OF HOT AND HUMID CONDITIONS WITH LIMITED CHANCES FOR CONVECTION
FOR SEVERAL MORE DAYS. THE CENTRAL GULF COAST REGION WILL BE ON
THE PERIPHERY OF THIS RIDGE THROUGH WEEKEND WITH A WEAKNESS ALOFT
SITUATED OVER NORTH FLORIDA AND THE SOUTHEAST. IMPULSES ROTATING
THE RIDGE MAY RESULT IN THE DEVELOPMENT OF SCATTERED CONVECTION...
BUT PRIMARILY ACROSS THE EASTERN THIRD OF THE FORECAST AREA. A
WEAK BACKDOOR COLD FRONT SITUATED TO THE NORTHEAST OF THE FORECAST
AREA OVER THE SOUTHEAST CONUS WILL ALSO SERVE AS A FOCUS FOR
CONVECTION. THIS BOUNDARY WILL REMAIN JUST TO THE EAST OF THE AREA
BEFORE WASHING OUT...BUT MAY BE CLOSE ENOUGH TO AID CONVECTION
CHANCES ACROSS SOUTH MISSISSIPPI. RAIN CHANCES WILL LIKELY
DECREASE AGAIN FOR THE FIRST HALF OF THE WORK WEEK AS THE
INFLUENCE OF THE UPPER RIDGE INCREASES ACROSS THE AREA AS IT
SHIFTS BACK TO THE EAST NORTHEAST AND BECOMES CENTERED OVER THE
OZARKS REGION. THE BEST CHANCES FOR ANY CONVECTION DURING THIS
PERIOD WILL REMAIN ACROSS THE COASTAL AREAS. MODELS DO INDICATE A
PATTERN CHANGE FOR THE END OF THE WEEK AND INTO NEXT WEEKEND AS
THE UPPER RIDGE RETROGRADES TO THE FOUR CORNERS REGION AS AN
UPPER TROUGH DEEPENS OVER THE EASTERN CONUS. THIS WILL ALLOW FOR A
COLD FRONT TO PUSH DEEP INTO THE SOUTH. THIS WILL RESULT IN HIGHER
RAIN CHANCES FOR THE AREA AS WELL AS SOME RELIEF IN THE
TEMPERATURE DEPARTMENT. IN THE MEANTIME HOWEVER...HIGHS MAINLY IN
THE MID 90S AND DEW POINTS IN THE 70S WILL PRODUCE HEAT INDICES PRIMARILY
IN THE 102 TO 108 DEGREE RANGE..JUST BELOW ADVISORY CRITERIA. 11
AVIATION...
CONVECTION THAT MOVED NEAR KGPT SEVERAL HOURS AGO IS WELL OUT INTO
THE GULF OF MEXICO. A NARROW BAND OF SHOWERS AND THUNDERSTORMS HAS
REDEVELOPED FROM NORTH OF KJAN TO KMOB. AT THIS POINT...IF THERE IS
A THREAT TO ANY LOCAL TERMINALS OVER THE NEXT SEVERAL HOURS...IT
WOULD LIKELY BE LIMITED TO KGPT. EXPECT GENERAL VFR CONDITIONS
THROUGH THE FORECAST PERIOD. WILL CARRY MENTION OF VCTS FOR
TERMINALS ACROSS THE SE HALF OF THE AREA INCLUDING KGPT...KASD...
KNEW...KMSY AND KHUM DURING THE AFTERNOON HOURS TODAY. ANY
THUNDERSTORMS AFFECTING A TERMINAL LIKELY TO PRODUCE MVFR CONDITIONS
FOR LESS THAN ONE HOUR. 35
MARINE...
THE WEAK NOCTURNAL COASTAL JET OVER THE NEARSHORE GULF COASTAL
WATERS EAST OF THE CHANDELEUR SOUND AND SOUTH OF THE MISSISSIPPI
SOUND APPEARS TO WEAKEN ONCE WE GET PAST THIS MORNING. FOR MUCH OF
THE REMAINDER OF THE FORECAST PERIOD...WINDS GENERALLY REMAIN 10
KNOTS OR BELOW WITH SEAS LIMITED TO 1 TO 2 FEET. 35
DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER FROM RED
RIVER LANDING TO DONALDSONVILLE.
POTENTIAL SPOT FORECAST FOR IRISH BAYOU MARSH FIRE.
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 96 76 95 76 / 20 10 20 10
BTR 96 77 96 77 / 20 10 20 10
ASD 96 78 95 77 / 30 20 20 10
MSY 96 79 96 79 / 30 20 30 10
GPT 95 79 95 78 / 40 30 20 10
PQL 95 77 95 76 / 40 30 20 10
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LAZ040-058-060>064-
072.
GM...NONE.
MS...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MSZ080>082.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1159 AM CDT SAT JUL 25 2015
.AVIATION...
CU FIELD DEVELOPING TODAY WHERE WE WERE VOID OF CU DURING THE DAY
FRIDAY. UPPER LEVEL RIDGE CENTERED ACROSS THE TX HILL COUNTRY AND
IS FAR ENOUGH WEST THAT WE COULD SEE SOME ISOLATED TSRA ACROSS OUR
EASTERN TAF SITES LATER TODAY/THIS EVENING. STILL FEEL LIKE
COVERAGE IS NOT SIGNIFICANT ENOUGH TO WARRANT A MENTION IN THE 18Z
TAF PACKAGE HOWEVER. CONVECTION ACROSS SC AR THIS MORNING IS
ORIENTED ALONG A 700MB THETAE AXIS WHICH IS FCST TO BACKDOOR
ITSELF INTO SW AR AND N LA LATER TODAY.
OTHERWISE...VFR CONDITIONS SHOULD PREVAIL THROUGH THE NEXT 24
HOURS. WINDS WILL BE MOSTLY VARIABLE THROUGH THE TAF
PERIOD...MAINLY LESS THAN 10KTS.
13
&&
.PREV DISCUSSION... /ISSUED 1132 AM CDT SAT JUL 25 2015/
DISCUSSION...
THE REMNANTS OF THE AC/CIRRUS SHIELD FROM THE OVERNIGHT CONVECTION
OVER NCNTRL AR HAS MOSTLY DIMINISHED THIS MORNING...WITH STRONG
HEATING ALREADY UNDERWAY WITH MOST LOCALES ALREADY IN THE LOW TO
MID 90S AS OF 16Z. AS EXPECTED...LOW LEVEL MOISTURE IS A LITTLE
DEEPER THIS MORNING COMPARED TO THE LAST COUPLE OF MORNINGS /PER
THE 12Z KSHV RAOB/...ALTHOUGH THE 850MB TEMP IS ABOUT 2 DEGREES
WARMER THAN 24 HOURS AGO. THIS HAS RESULTED IN 16Z TEMPS ABOUT 2-3
DEGREES WARMER THAN 24 HOURS AGO ACROSS MOST AREAS...WITH H850
RIDGING EXPECTED TO LINGER OVERHEAD THROUGH THE AFTERNOON. THIS
SHOULD RESULT IN AN EVEN HOTTER AFTERNOON...ALTHOUGH A COUPLE
FLIES IN THE OINTMENT PERTAIN TO THE INCREASE IN LOW LEVEL
MOISTURE AS WELL AS A WEAK SFC TROUGH THAT EXTENDS FROM WRN AND
SCNTRL AR INTO CNTRL MS/SRN AL.
ISOLATED CONVECTION HAS ALREADY FIRED OVER DALLAS COUNTY AR THIS
MORNING NEAR THIS BNDRY...WITH THE SHORT TERM PROGS DEPICTING A NW
TO SE H850 THETA-E AXIS NEAR THE SFC TROUGH OVER THESE
AREAS...WHICH MAY SAG MORE SE ACROSS EXTREME SRN AR INTO NCNTRL LA
THIS AFTERNOON. PW/S DO INCREASE TO 1.7-1.9 INCHES THIS AFTERNOON
OVER THESE AREAS...WITH STRONG HEATING AND THE DEEPENING LOW LEVEL
MOISTURE CONTRIBUTING TO A MORE UNSTABLE AIR MASS ON THE OUTER
PERIPHERY OF THE STOUT UPPER RIDGING OVER THE SRN PLAINS AND MID-
SOUTH REGION. IN FACT...THE LATEST HRRR AND SSEO RUNS DEPICT
ISOLATED CONVECTION DEVELOPING THIS AFTERNOON ACROSS THESE
AREAS...THUS HAVE ADDED SLIGHT CHANCE POPS THIS AFTERNOON.
HOWEVER...THE MAIN STORY WILL BE THE HEAT...WITH NEAR TRIPLE DIGIT
HEAT AND A LACK OF SUFFICIENT DRY AIR MIXING /AS OBSERVED THE LAST
COUPLE OF DAYS/ RESULTING IN DANGEROUS HEAT INDICES ACROSS MUCH OF
THE REGION. THE CURRENT HEAT ADVISORY STILL LOOKS GOOD FOR SE
OK/SW AR/EXTREME ERN TX/N LA...BUT DID INCREASE HEAT INDICES
SLIGHTLY ESPECIALLY OVER SW AR/N LA AS THESE AREAS SHOULD SEE HEAT
INDICES IN THE UPPER END OF THE ADVISORY CRITERIA. WILL ADDRESS A
POSSIBLE EXTENSION OF THE HEAT ADVISORY IN THE AFTERNOON
DISCUSSION AS LITTLE WILL CHANGE IN THE SHORT TERM.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 101 78 101 78 / 10 10 10 10
MLU 98 78 99 77 / 20 10 20 10
DEQ 98 73 98 75 / 10 10 10 10
TXK 100 77 99 77 / 10 10 10 10
ELD 98 76 98 76 / 20 10 20 10
TYR 99 78 100 78 / 0 0 0 0
GGG 99 77 101 78 / 0 0 10 0
LFK 98 75 98 75 / 0 0 10 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR ARZ050-051-059>061-
070>073.
LA...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LAZ001>006-010>014-
017>022.
OK...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR OKZ077.
TX...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TXZ097-112-126-138-
151.
&&
$$
15/13
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1132 AM CDT SAT JUL 25 2015
.DISCUSSION...
THE REMNANTS OF THE AC/CIRRUS SHIELD FROM THE OVERNIGHT CONVECTION
OVER NCNTRL AR HAS MOSTLY DIMINISHED THIS MORNING...WITH STRONG
HEATING ALREADY UNDERWAY WITH MOST LOCALES ALREADY IN THE LOW TO
MID 90S AS OF 16Z. AS EXPECTED...LOW LEVEL MOISTURE IS A LITTLE
DEEPER THIS MORNING COMPARED TO THE LAST COUPLE OF MORNINGS /PER
THE 12Z KSHV RAOB/...ALTHOUGH THE 850MB TEMP IS ABOUT 2 DEGREES
WARMER THAN 24 HOURS AGO. THIS HAS RESULTED IN 16Z TEMPS ABOUT 2-3
DEGREES WARMER THAN 24 HOURS AGO ACROSS MOST AREAS...WITH H850
RIDGING EXPECTED TO LINGER OVERHEAD THROUGH THE AFTERNOON. THIS
SHOULD RESULT IN AN EVEN HOTTER AFTERNOON...ALTHOUGH A COUPLE
FLIES IN THE OINTMENT PERTAIN TO THE INCREASE IN LOW LEVEL
MOISTURE AS WELL AS A WEAK SFC TROUGH THAT EXTENDS FROM WRN AND
SCNTRL AR INTO CNTRL MS/SRN AL.
ISOLATED CONVECTION HAS ALREADY FIRED OVER DALLAS COUNTY AR THIS
MORNING NEAR THIS BNDRY...WITH THE SHORT TERM PROGS DEPICTING A NW
TO SE H850 THETA-E AXIS NEAR THE SFC TROUGH OVER THESE
AREAS...WHICH MAY SAG MORE SE ACROSS EXTREME SRN AR INTO NCNTRL LA
THIS AFTERNOON. PW/S DO INCREASE TO 1.7-1.9 INCHES THIS AFTERNOON
OVER THESE AREAS...WITH STRONG HEATING AND THE DEEPENING LOW LEVEL
MOISTURE CONTRIBUTING TO A MORE UNSTABLE AIR MASS ON THE OUTER
PERIPHERY OF THE STOUT UPPER RIDGING OVER THE SRN PLAINS AND MID-
SOUTH REGION. IN FACT...THE LATEST HRRR AND SSEO RUNS DEPICT
ISOLATED CONVECTION DEVELOPING THIS AFTERNOON ACROSS THESE
AREAS...THUS HAVE ADDED SLIGHT CHANCE POPS THIS AFTERNOON.
HOWEVER...THE MAIN STORY WILL BE THE HEAT...WITH NEAR TRIPLE DIGIT
HEAT AND A LACK OF SUFFICIENT DRY AIR MIXING /AS OBSERVED THE LAST
COUPLE OF DAYS/ RESULTING IN DANGEROUS HEAT INDICES ACROSS MUCH OF
THE REGION. THE CURRENT HEAT ADVISORY STILL LOOKS GOOD FOR SE
OK/SW AR/EXTREME ERN TX/N LA...BUT DID INCREASE HEAT INDICES
SLIGHTLY ESPECIALLY OVER SW AR/N LA AS THESE AREAS SHOULD SEE HEAT
INDICES IN THE UPPER END OF THE ADVISORY CRITERIA. WILL ADDRESS A
POSSIBLE EXTENSION OF THE HEAT ADVISORY IN THE AFTERNOON
DISCUSSION AS LITTLE WILL CHANGE IN THE SHORT TERM.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 101 78 101 78 / 10 10 10 10
MLU 98 78 99 77 / 20 10 20 10
DEQ 98 73 98 75 / 10 10 10 10
TXK 100 77 99 77 / 10 10 10 10
ELD 98 76 98 76 / 20 10 20 10
TYR 99 78 100 78 / 0 0 0 0
GGG 99 77 101 78 / 0 0 10 0
LFK 98 75 98 75 / 0 0 10 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR ARZ050-051-059>061-
070>073.
LA...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LAZ001>006-010>014-
017>022.
OK...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR OKZ077.
TX...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TXZ097-112-126-138-
151.
&&
$$
15
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
323 PM EDT SAT JUL 25 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 323 PM EDT SAT JUL 25 2015
HOT AND DRY WEATHER WILL PREVAIL INTO NEXT WEEK WITH HIGHS IN THE
UPPER 80S. THE NEXT CHANCE FOR SHOWERS AND THUNDERSTORMS ARRIVES
WEDNESDAY. THIS WILL BE FOLLOWED BY A RETURN TO DRY CONDITIONS AND
SLIGHTLY COOLER TEMPERATURES WITH HIGHS IN THE LOWER 80S.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 323 PM EDT SAT JUL 25 2015
STILL EXPECT SHOWERS AND THUNDERSTORMS TO BE LIMITED TO OUR FAR
SOUTHEASTERN ZONES THIS AFTERNOON AND EVENING AS STABILIZING
MARINE AIR HAS OVERSPREAD MUCH OF THE REMAINING AREA. GIVEN
MODERATE INSTABILITY /MLCAPE 1500 J PER KG/ AND SURFACE
CONVERGENCE ALONG THE PREFRONTAL TROUGH IN THIS AREA...WILL NEED
TO MONITOR FOR STRONG STORMS.
AFTER PRECIPITATION EXITS THE AREA THIS EVENING...MAIN FORECAST
CONCERN IS MAXIMUM TEMPERATURES. WENT NEAR OR ABOVE GUIDANCE WITH
WIDESPREAD UPPER 80S EXPECTED BOTH SUNDAY AND MONDAY AFTERNOONS.
DURING THIS TIME...AN UPSTREAM UPPER RIDGE GRADUALLY AMPLIFIES AND
APPROACHES THE FORECAST AREA WHICH IS CONDUCIVE TO MID-LEVEL
SUBSIDENCE AND SURFACE ANTICYCLOGENESIS. THIS PATTERN MAKES DRY
CONDITIONS AND LIMITED CLOUDS HIGHLY PROBABLE.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 323 PM EDT SAT JUL 25 2015
THE FOCUS FOR THIS FORECAST IS CONVECTION WITH THE PASSAGE OF A
RATHER STRONG (FOR THIS TIME OF YEAR) COLD FRONT IN THE WEDNESDAY
TIME FRAME. BEYOND THAT THE THEME OF OVERALL COOL SUMMER FOR
SOUTHWEST MICHIGAN WILL CONTINUE AS A LONGWAVE TROUGH RE-
ESTABLISHES ITSELF OVER THE EASTERN CONUS AND ADJACENT SOUTHERN
CANADA.
OVERALL THE MODELS ARE IN GOOD AGREEMENT THROUGH MOST OF THIS COMING
WEEK... WELL AT LEAST THROUGH THURSDAY ANYWAY. BEYOND THAT THERE ARE
ISSUES WITH THE NEXT SHORTWAVE RIDGE/TROUGH MOVING IN FROM THE
PACIFIC INTO THE CONUS. IT SHOULD BE NOTED THAT THE OPERATIONAL GFS
IS AT ODDS WITH ITS OWN ENSEMBLE MEAN BEYOND THURSDAY. THE ENSEMBLE
MEAN OF THE GFS IS IN AGREEMENT WITH OPERATIONAL ECMWF SO I AM GOING
WITH THAT IDEA.
THE BIG PICTURE IS THE LONGWAVE RIDGE ...WHICH IS CURRENTLY OVER THE
CENTRAL CONUS RETROGRADES TO THE WESTERN CONUS BY THE MIDDLE OF NEXT
WEEK. THIS HAPPENS AS A SERIES OF STRONG PACIFIC SYSTEMS TRACK EAST
FROM THE EASTERN NORTH PACIFIC OCEAN INTO THE SOUTHERN CANADA AND
THE NORTHERN CONUS. IT IS THE LEAD SHORTWAVE..WHICH IS CURRENTLY A
CLOSED UPPER LOW AND SURFACE SYSTEM OVER THE GULF OF ALASKA. THIS
SYSTEM TRACKS OVER THE UPPER RIDGE IN THE TUESDAY TIME FRAME TO HELP
DIG THE EASTERN TROUGH ONCE AGAIN. IT IS THIS DIGGING INTO THE
EASTERN TROUGH OF THAT SYSTEM THAT BRING SOUTHWEST MICHIGAN THE
CONVECTION ON WEDNESDAY.
SO...HOW STRONG WILL THE CONVECTION BE? ONCE AGAIN... AS IT HAS BEEN
MORE TIMES THAN I WANT TO COUNT THIS SUMMER...THE JUXTAPOSITION OF
THE UPPER LEVEL JET...THE LOW LEVEL JET AND THE TIME OF DAY THIS ALL
HAPPENS IS VERY MUCH NOT OPTIMAL FOR SIGNIFICANT THUNDERSTORMS.
THE PRIMARY UPPER LEVEL JET ON BOTH THE ECMWF AND GFS GO WELL TO
THE NORTH AND WEST OF MICHIGAN AND AS A RESULT WE DO NOT GET A
GOOD LOW LEVEL JET TO AID THE CAUSE OF A SIGNIFICANT THUNDERSTORM
EVENT. LIKELY THERE WILL BE SOME THUNDERSTORMS WITH THE FRONT BUT
THIS LIKELY WILL NOT BRING RAIN TO ALL AREAS AND EVEN THOSE PLACES
THAT DO GET RAIN...LIKELY WILL NOT SEE ALL THAT MUCH (SYSTEM
MOVING THROUGH TO FAST).
BEYOND THAT THE COLD AIR MOVES BACK IN AND THERE MAY BE COLD AIR
INSTABILITY SHOWERS THURSDAY OVER OUR NORTHEAST CWA. I DID NOT PLAY
THIS TO BIG JUST YET BUT IT WILL HAVE TO BE WATCHED. ONE OTHER THING
TO NOTE... THE GFS HAS ALL SUMMER HAD A WARM BIAS ON THE
TEMPERATURES BEHIND THESE COLD FRONTS. MORE THAN LIKELY IT WILL
BE COOLER THAN WE ARE CURRENTLY FORECASTING THURSDAY AND FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 156 PM EDT SAT JUL 25 2015
GENERALLY MVFR CIGS PREVAIL AHEAD OF THE SECONDARY COLD FRONT
(WHICH IS CURRENTLY NEAR ROUTE 10) . IT IS THAT SECONDARY COLD
FRONT THAT IS BOTH THE FOCUS FOR DEVELOPING SHOWERS AND CLEARING
OF THE LOW CLOUDS BEHIND IT. ALSO THE WEST WIND LAKE SHADOW IS
CLEARING ALL CLOUDS WEST OF US-31. I USED THE HRRR LOW 925 TO 850
MB RH AS A GUIDE TO CLEAR OUT THE LOW CLOUDS AND ALSO HELP DECIDE
JUST WHERE TO HAVE THE VCSH IN THE TAFS.
FOR THE MOST PART THE MVFR CIGS SHOULD MIX OUT TO VFR CIGS BY 21Z
AT ALL TAF SITES...THAT IS JUST FROM DAY TIME MIXING AND NOT
RELATED TO THE FRONTAL PASSAGE. THE ACTUAL CLEARING OF THE CLOUDS
WILL BE BEHIND THE SECONDARY COLD FRONT THAT SHOULD OCCUR IN THE
00Z TO 03Z TIME FRAME. MKG SHOULD CLEAR SOON DUE TO THE LAKE
SHADOW MOVING INLAND.
THE CONVECTION AHEAD OF THE SECONDARY COLD FRONT WILL LARGELY STAY
EAST OF THE TAF SITES. THIS IS TYPICAL FOR WHAT HAPPENS WITH WEST
WINDS AT LOW LEVELS AT THIS TIME OF YEAR. I DID HOWEVER PUT VCSH
AT LAN AND JXN TAF SITES JUST IN CASE SHOWERS MAKE IT A TOUCH
FARTHER WEST.
BUFKIT TIME SECTIONS AND THE NAMDNG5 FORECAST DO SUGGEST THERE
COULD BE FROM FOG AT THE EASTERN TAF SITES DUE TO LIGHT WINDS
...CLEAR SKIES BUT MY CONFIDENCE WAS NOT HIGH GIVEN THERE IS
COLD ADVECTION GOING ON (HELP MIXING OUT THE FOG). LATE TAF
FORECAST MAY HAVE TO ADD FOG FOR THE EASTERN TAF SITES TONIGHT.
&&
.MARINE...
ISSUED AT 323 PM EDT SAT JUL 25 2015
NO CONCERNS IN THE SHORT TERM. VERY LIGHT WINDS OVERALL
SHOULD SHOULD BE DOMINATED BY LAKE/LAND BREEZES AT THE LAKESHORE
WITH ONSHORE WINDS DURING THE DAY AND OFFSHORE WINDS OVERNIGHT.
&&
.HYDROLOGY...
ISSUED AT 1137 AM EDT SAT JUL 25 2015
NO FLOODING CONCERNS EXIST THROUGH THE NEXT SEVERAL DAYS.
RECENT DRY CONDITIONS AND LITTLE EXPECTED RAINFALL HAS RESULTED
IN FALLING RIVER LEVELS. A FEW SCATTERED STORMS ARE EXPECTED TODAY
WITH VERY LOCALIZED HEAVY RAINFALL POSSIBLE. HOWEVER...THIS MAY BE
BRIEF WITH THE LACK OF ANY WIDESPREAD MOISTURE.
ALL RIVERS ARE WELL WITHIN BANKS AND THE STEADY OR FALLING TREND
WILL LIKELY CONTINUE THROUGH THE NEXT FEW DAYS. WARM AND HUMID
CONDITIONS WILL LACK MUCH IN THE WAY OF RAINFALL. A MID WEEK COLD
FRONT WILL HELP TO INCREASE RAIN CHANCES...BUT EVEN THESE TOTALS
SHOULD WILL BE RELATIVELY LIGHT IN REGARDS TO ANY HIGHLIGHTING AND
HYDRO ISSUES.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...WDM
AVIATION...WDM
HYDROLOGY...JAM
MARINE...TJT
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
157 PM EDT SAT JUL 25 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 330 AM EDT SAT JUL 25 2015
IT WILL FEEL LIKE THE DOG DAYS OF SUMMER AS WE HEAD THROUGH THE REST
OF THE WEEKEND AND INTO THE MIDDLE PART OF THE WORK WEEK. HIGHS WILL
LIKELY TOP OUT IN THE MIDDLE 80S TODAY WITH UPPER 80S IN MANY AREAS
FOR SUNDAY AND MONDAY. TUESDAY LOOKS TO BE THE WARMEST DAY OF THE
NEXT WEEK AS WE WILL LIKELY PUSH TO OR EXCEED 90 DEGREES. A
WEAKENING COLD FRONT IS EXPECTED TO SLIDE THROUGH SOUTHWEST LOWER
MICHIGAN TODAY AND BRING WITH IT SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WIDESPREAD PRECIPITATION IS NOT EXPECTED...IN FACT MANY
AREAS WILL REMAIN DRY. FAIR AND DRY WEATHER IS ON TAP FOR SUNDAY
INTO EARLY NEXT WEEK AS HIGH PRESSURE WILL BE SITUATED OVER THE
AREA.
&&
.UPDATE...
ISSUED AT 1101 AM EDT SAT JUL 25 2015
TRIMMED POPS CONSIDERABLY THIS AFTERNOON FOR THE WESTERN TWO
THIRDS OF THE FORECAST AREA. THIS IS BASED LARGELY ON THE LAST
SEVERAL RUNS OF THE HRRR. SURFACE OBSERVATIONS SHOW A CONSIDERABLE
SHIFT TO WESTERLY FLOW AT THE LAKESHORE...HERALDING THE APPROACH
OF THE STABLE MARINE LAYER OFF LAKE MICHIGAN. THIS AND
CONSIDERABLE CLOUDINESS OVER LOWER MICHIGAN SHOULD LIMIT
DESTABILIZATION OVER MOST OF SOUTHWEST LOWER MICHIGAN. CLOUDINESS
SHOULD GRADUALLY ERODE FROM WEST TO EAST. COLD FRONT CURRENTLY
EXTENDING FROM FAR NORTHERN LAKE MICHIGAN THROUGH MADISON
WISCONSIN WILL PROVIDE A FOCUS FOR DEEPER CONVECTION...MAINLY OVER
SOUTH-CENTRAL AND SOUTHEAST LOWER MICHIGAN. THE OVERALL SEVERE
THREAT REMAINS LIMITED. PLEASE SEE THE SPC DAY1 OUTLOOK FOR
FURTHER DETAILS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
CONCERNS IN THE SHORT TERM ARE RELATED TO SHOWER AND STORM CHANCES
TODAY AND THEN TWEAKING HIGH TEMPERATURES THE NEXT COUPLE DAYS AS WE
WILL BE QUITE WARM.
AS FOR CONVECTION TODAY...IT LOOKS LESS AND LESS IMPRESSIVE WITH
EACH MODEL RUN. THE HRRR GUIDANCE IS ONLY SHOWING SCATTERED STORMS
AT BEST. THE LATEST RAP GUIDANCE IS INDICATING MOST UNSTABLE CAPE
VALUES OF 1000-2000 J/KG WHICH IS MORE THAN ENOUGH...BUT OTHER
FACTORS LIMIT THE THREAT. THEY ARE NAMELY...THE MAIN SHORTWAVE IS
WELL NORTH OF THE AREA AND A WIND OFF THE LAKE WILL LIKELY TEMPER
INSTABILITY DURING THE AFTERNOON. MID LEVEL LAPSE RATES ARE NOT
STEEP EITHER...ON THE ORDER OF 5.5 C/KM. THE LLJ AND 850MB MOISTURE
TRANSPORT HAVE TRENDED DOWN AS WELL. BOTTOM LINE...LOOKING FOR
SCATTERED STORMS TO DEVELOP MIDDAY AND WORK SOUTH/EAST OUT OF THE
AREA DURING THE AFTERNOON HOURS. ANY CHANCE OF A STRONG STORM WOULD
BE DURING THE AFTERNOON TOWARDS LAN/BTL/JXN.
OTHERWISE FAIR WEATHER IS EXPECTED WITH HIGH PRESSURE BUILDING IN
BEHIND THE WEAKENING COLD FRONT. AFTER TODAY WITH CLOUDS ASSOCIATED
WITH THE FRONT...SKIES SHOULD BE MAINLY CLEAR. THINKING WE WILL PUSH
INTO THE MID 80S TODAY...CLOUD COVER IS A BIT OF A CONCERN WHICH
COULD TREND THINGS EITHER SIDE OF THOSE NUMBERS. UPPER 80S LOOK
PRETTY SOLID FOR SUNDAY AND MONDAY GIVEN 850MB TEMPS IN THE 17-19C
RANGE.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 330 AM EDT SAT JUL 25 2015
OUR MAIN FOCUS OF THE LONG TERM IS THE FRONTAL PASSAGE THAT IS
EXPECTED DURING THE MID-WEEK TIME FRAME...AND THE CHCS OF CONVECTION
THAT WILL ACCOMPANY THE FRONT.
THE BEGINNING OF THE PERIOD IS EXPECTED TO BE HOT AND HUMID WITH
LITTLE CHCS OF RAIN INITIALLY. WE WILL HAVE A FAIRLY DECENT UPPER
RIDGE IN PLACE. THIS UPPER RIDGE WITH HIGH HEIGHTS WILL SUPPORT THE
HOT WEATHER AND WILL CAP THE ATMOSPHERE OFF FROM ANY PCPN FROM
OCCURRING. WE ARE LOOKING AT A GOOD CHANCE OF LOWER 90S ON TUE WITH
H850 TEMPS APPROACHING 20C.
THERE IS A LITTLE UNCERTAINTY WITH THE SPECIFIC TIMING OF THE
SHOWERS/STORMS WITH THE FRONT MID-WEEK. THE CONSENSUS OF THE CHC OF
SHOWERS/STORMS LOOKS TO OCCUR TUE NIGHT INTO WED. SOME MODELS ARE A
LITTLE EARLIER...AND SOME ARE A LITTLE LATER. IT DOES NOT LOOK LIKE
A STRONG FEED OF GULF MOISTURE WILL BE PRESENT. ENOUGH SHOULD BE
AROUND WITH THE STRENGTH OF THE FRONT TO BRING A DECENT CHC OF RAIN.
SEVERE CHCS ARE NOT LOOKING REAL STRONG AT THIS POINT. THERE DOES
LOOK TO BE A GOOD DEAL OF INSTABILITY PRESENT...ESPECIALLY DURING
PEAK HEATING ON WED. DEEP LAYER SHEAR IS LACKING A BIT WITH THE
BETTER WIND FIELDS LAGGING THE FRONT/STORMS A BIT. WE WILL CONTINUE
TO MONITOR THIS POTENTIAL AND THE TRENDS OVER THE NEXT FEW DAYS.
WE WILL SEE A COOL DOWN ALONG WITH DRIER CONDITIONS FOR THE THU AND
FRI TIME FRAME. WE WILL SEE A TROUGH OVER THE AREA EVENTUALLY GIVING
WAY TO A SFC RIDGE. NW FLOW ALOFT AND IN THE LOWER LEVELS WILL COOL
US OFF A BIT. IT DOES NOT LOOK TOO COLD AT THIS TIME WITH H850 TEMPS
DROPPING INTO THE LOWER TEENS C.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 156 PM EDT SAT JUL 25 2015
GENERALLY MVFR CIGS PREVAIL AHEAD OF THE SECONDARY COLD FRONT
(WHICH IS CURRENTLY NEAR ROUTE 10) . IT IS THAT SECONDARY COLD
FRONT THAT IS BOTH THE FOCUS FOR DEVELOPING SHOWERS AND CLEARING
OF THE LOW CLOUDS BEHIND IT. ALSO THE WEST WIND LAKE SHADOW IS
CLEARING ALL CLOUDS WEST OF US-31. I USED THE HRRR LOW 925 TO 850
MB RH AS A GUIDE TO CLEAR OUT THE LOW CLOUDS AND ALSO HELP DECIDE
JUST WHERE TO HAVE THE VCSH IN THE TAFS.
FOR THE MOST PART THE MVFR CIGS SHOULD MIX OUT TO VFR CIGS BY 21Z
AT ALL TAF SITES...THAT IS JUST FROM DAY TIME MIXING AND NOT
RELATED TO THE FRONTAL PASSAGE. THE ACTUAL CLEARING OF THE CLOUDS
WILL BE BEHIND THE SECONDARY COLD FRONT THAT SHOULD OCCUR IN THE
00Z TO 03Z TIME FRAME. MKG SHOULD CLEAR SOON DUE TO THE LAKE
SHADOW MOVING INLAND.
THE CONVECTION AHEAD OF THE SECONDARY COLD FRONT WILL LARGELY STAY
EAST OF THE TAF SITES. THIS IS TYPICAL FOR WHAT HAPPENS WITH WEST
WINDS AT LOW LEVELS AT THIS TIME OF YEAR. I DID HOWEVER PUT VCSH
AT LAN AND JXN TAF SITES JUST IN CASE SHOWERS MAKE IT A TOUCH
FARTHER WEST.
BUFKIT TIME SECTIONS AND THE NAMDNG5 FORECAST DO SUGGEST THERE
COULD BE FROM FOG AT THE EASTERN TAF SITES DUE TO LIGHT WINDS
...CLEAR SKIES BUT MY CONFIDENCE WAS NOT HIGH GIVEN THERE IS
COLD ADVECTION GOING ON (HELP MIXING OUT THE FOG). LATE TAF
FORECAST MAY HAVE TO ADD FOG FOR THE EASTERN TAF SITES TONIGHT.
&&
.MARINE...
ISSUED AT 330 AM EDT SAT JUL 25 2015
WAVES OF 1 TO 3 FEET ARE EXPECTED THIS MORNING FROM GRAND HAVEN
NORTHWARD IN A ZONE WHERE SOUTHWEST WINDS OF 10 TO 20 KNOTS WILL
BUILD WAVE HEIGHTS. WINDS LOOK A BIT DOWN FROM WHAT WE WERE SEEING
IN THE MODELS THE LAST COUPLE NIGHTS...SO THE MORE WIDESPREAD 2 TO 4
FOOT WAVES LOOK LESS LIKELY.
AFTER THIS MORNING...QUIET WEATHER OUT ON THE BIG LAKE THE REST OF
THE WEEKEND WITH HIGH PRESSURE IN PLACE. WAVES OF 2 FEET OR LESS AND
WINDS LESS THAN 15 KNOTS SHOULD BE COMMON PLACE.
&&
.HYDROLOGY...
ISSUED AT 1137 AM EDT SAT JUL 25 2015
NO FLOODING CONCERNS EXIST THROUGH THE NEXT SEVERAL DAYS.
RECENT DRY CONDTIONS AND LITTLE EXPECTED RAINFALL HAS RESULTED IN
FALLING RIVER LEVELS. A FEW SCATTERED STORMS ARE EXPECTED TODAY
WITH VERY LOCALIZED HEAVY RAINFALL POSSIBLE. HOWEVER...THIS MAY BE
BRIEF WITH THE LACK OF ANY WIDESPREAD MOISTURE.
ALL RIVERS ARE WELL WITHIN BANKS AND THE STEADY OR FALLING TREND
WILL LIKELY CONTINUE THROUGH THE NEXT FEW DAYS. WARM AND HUMID
CONDITIONS WILL LACK MUCH IN THE WAY OF RAINFALL. A MID WEEK COLD
FRONT WILL HELP TO INCREASE RAIN CHANCES...BUT EVEN THESE TOTALS
SHOULD WILL BE RELATIVELY LIGHT IN REGARDS TO ANY HIGHLIGHTING AND
HYDRO ISSUES.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...TJT
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...JAM
MARINE...DUKE
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1255 PM EDT SAT JUL 25 2015
.AVIATION...
A COLD FRONT WAS LOCATED FROM OSC TO MKG AND WILL MOVE THROUGH
SOUTHEAST MICHIGAN THIS AFTERNOON AND EVENING. SHOULD GET THROUGH
MBS BY 20Z...FNT BY 21-22Z AND DTW BY 00Z THIS FRONT WILL BRING A
WINDOW OF LOWER CIGS AND POSSIBLE TSTORMS. VFR CONDITIONS WILL
PREVAIL BOTH BEFORE AND AFTER THIS NARROW WINDOW OF THE FRONTAL
PASSAGE IN WHICH MVFR CIGS/VSBYS MAY OCCUR. CONFIDENCE IS LOW WITH
COVERAGE OF POTENTIAL TSTORMS AS SIGNALS ARE POINTING TO
ISOLATED/SCATTERED COVERAGE. WILL INCLUDE A BRIEF 2 HOUR TEMPO TO
ACCOUNT FOR THIS NARROW WINDOW OF POTENTIAL FOR PTK SOUTHWARD WITH
JUST SHOWERS FOR FNT/MBS DUE TO EARLIER TIMING AND LESS INSTABILITY.
NORTHERLY WINDS BEHIND THE FRONT WILL BRING DRIER AIR BACK TO THE
AREA ERODING THE CLOUDS THIS EVENING INTO THE OVERNIGHT FROM NORTH
TO SOUTH. WINDS HAVE BRIEFLY INCREASED FROM THE SW AHEAD OF THE
FRONT BUT WILL RELAX SOME OVERNIGHT AS WIND SWITCH TO NORTHERLY WITH
THE NEXT HIGH SETTLING IN.
FOR DTW...COLD FRONT LOOKS TO BE MOVING THROUGH DURING PEAK
HEATING...WARRANTING THE TEMPO FOR TSTORMS FROM 21-23Z. UPSTREAM OBS
AND FORECAST SOUNDINGS SUGGEST CIGS WILL HOVER NEAR THE VFR/MVFR
THRESHOLD BUT THINKING IS VFR WILL DOMINATE WITH MVFR BEING MORE
SCATTERED SO WILL FAVOR VFR WITH THE TAFS.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM FOR CIGS AOB 5KFT THIS AFTERNOON AND EVENING.
* LOW FOR THUNDERSTORMS THIS AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 1033 AM EDT SAT JUL 25 2015
UPDATE...
CURRENT FORECAST ON TRACK FOR SATURDAY AFTERNOON AND EVENING. 12Z
SOUNDING FOR DTX SUGGESTS ABOUT 1000 K/KG OF ML CAPE WITHOUT ANY
ADDITIONAL MOISTURE ADVECTION IN THE MIXED LAYER. THERE IS SOME
POOLING OF THAT MOISTURE ALONG THE FRONT GIVEN THE DEW POINTS IN
THE UPPER 60S TO AROUND 70 FOR EXTREME SE WI AND NRN IL. STILL
SOME QUESTION IF WE GET ALL OF THAT LOW LEVEL MOISTURE TO REALIZE
2000 J/KG OF ML CAPE...BUT THERE SHOULD BE ENOUGH OF AN INCREASE
TO GET IN THE 1500 J/KG NEIGHBORHOOD. WIND FIELDS MAY BE STRONGEST
THIS MORNING AND ACTUALLY WEAKEN THROUGH THE AFTERNOON. STILL MAY
BE ENOUGH FOR SOME ORGANIZATION OF THE CONVECTION AND MAYBE ONE OR
TWO STORMS TO GET CLOSE TO SEVERE LIMITS. 00Z HI RES RUNS ALL
WERE BULLISH ON MORNING CONVECTION ACROSS NRN AND WC LOWER WHICH
WOULD HAVE IMPACTS ON ITS DEPICTION OF CONVECTION FOR SE LOWER.
THE LATER HRRR AND RAP/RUC CYCLES ARE A LITTLE BETTER AND CONTINUE
THE IDEA OF 16-20Z TIMING FOR THE TRI CITIES...18-22Z FOR THUMB TO
ARB AND 20-00Z FOR METRO DETROIT.
CLOUDS WERE QUITE VARIABLE ACROSS LOWER MICHIGAN. EXPECT THAT TO
CONTINUE AS THE LOWER SC LIFTS INTO A CU FIELD WHILE AREAS OF AC
CONTINUE TO MOVE ACROSS THE REGION. END RESULT SHOULD BE ENOUGH
SUN TO REACH FORECAST HIGHS WHILE THERE WILL NOT BE TOO MUCH SUN
TO GO ANY HIGHER.
PREV DISCUSSION...ISSUED 356 AM EDT SAT JUL 25 2015
SHORT TERM...TODAY AND TONIGHT
A WEAKENING COLD FRONT WILL PASS THROUGH LOWER MI TODAY BRINGING THE
CHANCE OF SHOWERS AND THUNDERSTORMS. THE PARENT LOW FOR THE FRONT IS
LOCATED OVER NORTHERN ONTARIO AND WILL CONTINUE SLOWLY EASTWARD
THROUGH THE DAY WHILE THE FRONT PIVOTS AROUND IT AND THROUGH THE
AREA. THE TIMING OF THE FRONT PASSAGE WILL BE IN THE AFTERNOON
AROUND 18-00Z...DURING PEAK HEATING. THIS WILL OF COURSE FAVOR STORM
DEVELOPMENT AS SFC TEMPS REACH INTO THE LOW/MID 80S WITH DEWPOINTS
LOOKING TO REACH 70. WILL CONTINUE WITH CHANCE POPS FOR SHOWERS AND
THUNDERSTORMS TODAY WITH THE MAIN ADJUSTMENT COMING IN THE TIMING OF
THE PRECIP...ELIMINATING ALL POPS BEFORE 14Z AS THE LINE OF
CONVECTION IS STILL FAR TO THE WEST OVER CENTRAL WI. DETAILS OF THE
SETUP TO FOLLOW...
THE UPPER LEVEL JET MAX HAS WORKED ITS WAY ACROSS THE MS RIVER AND
WILL REACH MID MI THIS MORNING. MODELS ALL SHOW THIS TO WEAKEN
THROUGH THE DAY FROM 100 KNOTS DOWN TO AROUND 70 KNOTS. THIS WILL
ALLOW DECENT SHEAR AHEAD OF THE FRONT WITH 0-3KM VALUES AROUND 25-30
KNOTS WHICH WILL BE ENOUGH TO TRY TO ORGANIZE SOME STORMS THAT CAN
DEVELOP. THIS WILL HELP COMPENSATE SOMEWHAT FOR THE LACK OF NOTABLE
FRONTAL FORCING ANYWHERE ALONG THE FRONT. AS HAS BEEN THE CASE MUCH
OF THE CONVECTIVE SEASON...MID LEVEL LAPSE RATES LOOK TO BE VERY
WEAK ONCE AGAIN BUT LL LAPSE RATES WILL BE PRETTY GOOD AS SFC TEMPS
QUICKLY RISE INTO THE MID 80S ONCE AGAIN. CAPE WILL ALSO BE
FAVORABLE AS A CORRIDOR OF 70 DEGREE DEWPOINTS AHEAD OF THE FRONT
SLIDES THROUGH THE AREA. A FAIR VALUE LOOKS TO BE AROUND 1500-2000
J/KG AVAILABLE THIS AFTERNOON. BEST CHANCES FOR ORGANIZED...POSSIBLE
STRONG TO SEVERE...STORMS WILL BE OVER THE SOUTHERN AND EASTERN
LOCATIONS AS THEY WILL HAVE SEVERAL ADDITIONAL HOURS OF HEATING TO
WORK WITH. IN ADDITION THERE APPEARS TO BE A SECONDARY COLD FRONT OR
SHORTWAVE SLIDING IN THIS AFTERNOON WHICH MAY PROVIDE A LITTLE EXTRA
BOOST LATER IN THE DAY. FOR ANY ONE LOCATION THERE LOOKS TO BE
AROUND A 3-5 HOUR WINDOW WHERE THESE ISOLATED TO SCATTERED STORMS
COULD IMPACT THEM. MBS WILL START EARLY IN THE DAY AS THE FRONT
APPROACHES AROUND 14Z...WHICH WILL LIMIT STRENGTH OF THESE
STORMS...WITH DTW HOLD OFF TIL CLOSER TO 18-20Z FOR A START TIME.
ALL ACTIVITY LOOKS TO PASS TO THE SOUTH/EAST BY 00Z. ANY ORGANIZED
STORM WILL HAVE THE POTENTIAL TO PRODUCE 60 MPH GUSTS AND/OR LARGE
HAIL. SPC HAS SOUTHEAST LOWER MI INCLUDED IN THE MARGINAL RISK AREA
WHICH SEEMS REASONABLE FOR THE SETUP.
ONCE THE FRONT PASSES...HIGH PRESSURE WILL CLEAR OUT THE CLOUDS FOR
THE OVERNIGHT BUT TEMPS WILL REMAIN ELEVATED AS THE POST FRONTAL
AIRMASS IS SPORTING DEWPOINTS IN THE LOW 60S.
LONG TERM... SUNDAY THROUGH FRIDAY
A TEMPORARY DIP IN THE UPPER HEIGHT FIELD OVER THE NEXT 24 HOURS
WILL HELP EASE THE ATTENDANT WEAK FRONT INTO THE OHIO VALLEY BY
EARLY SUNDAY. POST-FRONTAL ENVIRONMENT SUNDAY WILL BE MORE NOTABLE
FOR A REDUCTION IN HUMIDITY RELATIVE TO TODAY...WITH NO REAL CHANGE
EXPECTED IN THE TEMPERATURES. THE DRIER AND MORE STABLE CONDITIONS
AS HIGH PRESSURE SLIDES THROUGH WILL TRANSLATE INTO A HIGH DEGREE OF
SUNSHINE. THIS INSOLATION POTENTIAL INTO A DRIER AND MODESTLY MIXED
PROFILE FAVORS A GREATER DIURNAL TEMPERATURE RESPONSE...AND WILL
NUDGE HIGHS UP A COUPLE DEGREE ACCORDINGLY FOR SUNDAY AFTERNOON.
GOING FORECAST HOLDING FIRM WITH EXPECTATIONS THAT CONVECTIVE
ACTIVITY THAT EMERGES ALONG THE FRONTAL ZONE WILL REMAIN SOUTH OF
THE BORDER SUNDAY AND SUNDAY NIGHT.
PREDOMINANT SOUTHERN CONUS UPPER RIDGING WILL UNDERGO STEADY
AMPLIFICATION INTO THE GREAT LAKES THROUGH THE EARLY WEEK PERIOD.
THE ACCOMPANYING RISE IN MEAN THICKNESSES THROUGHOUT THE COLUMN WILL
TRANSLATE INTO SEVERAL DAYS OF ABOVE NORMAL WARMTH. WARMEST
CONDITIONS CENTERED ON THE TUESDAY AND WEDNESDAY PERIODS AS THE
UPPER RIDGE AXIS PIVOTS OVERHEAD...850 MB TEMPERATURES REACHING INTO
THE 18 TO 20C RANGE DURING THIS TIME. THIS WILL SUPPORT READINGS IN
THE VICINITY OF 90 DEGREES BOTH DAYS. CONVECTIVE POTENTIAL HAMPERED
BY THE INCREASING MID LEVEL TEMPERATURES AND LACK OF SUFFICIENT
FORCING BOTH MONDAY AND TUESDAY. NEXT FRONTAL PASSAGE CENTERED
WITHIN THE WEDNESDAY AND WEDNESDAY NIGHT PERIODS...AS THE SOUTHERN
EXTENT OF HEIGHT FALLS ASSOCIATED WITH A DEEPENING WAVE LIFTING INTO
SOUTHERN CANADA ENTERS THE GREAT LAKES. THIS WILL PROVIDE THE NEXT
OPPORTUNITY FOR THUNDERSTORM DEVELOPMENT. COOLER...OR A TRANSITION
BACK TOWARD NORMAL...TEMPERATURES IN THE WAKE OF THE FRONT FOR THE
END OF THE WORK WEEK.
MARINE...
A COLD FRONT ACROSS LAKE HURON AND LOWER MICHIGAN TODAY. THIS FRONT
WILL BRING A CHANCE OF THUNDERSTORMS TO ALL MARINE AREAS. MODERATE
SOUTHWESTERLY WINDS IN ADVANCE OF THIS FRONT...SHIFTING TO NORTH
POST FRONT THROUGH EARLY TONIGHT. WEAK HIGH PRESSURE SETTLING
ACROSS THE REGION WILL BRING FAVORABLE MARINE CONDITIONS SUNDAY
THROUGH EARLY NEXT WEEK.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....RBP
UPDATE.......RBP
SHORT TERM...DRK
LONG TERM....MR
MARINE.......MR
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
416 PM CDT SAT JUL 25 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 415 PM CDT SAT JUL 25 2015
A COUPLE OF MCVS FROM CONVECTION EARLIER IN THE DAY OVER SODAK ARE
NOW DRIFTING OVER MN...BUT ENCOUNTERING DRY HIGH PRESSURE AT THE SFC
AS THEY DO SO...SO THEY HAVE BEEN ABLE TO PRODUCE LITTLE MORE THAN
AN INCREASE IN MID/UPPER CLOUDS. THE AREA TO WATCH THIS AFTERNOON
THOUGH IS CENTRAL SODAK OUT BY MILLER AND CHAMBERLAIN WHERE SEVERAL
SEVERE WEATHER PARAMETERS ARE LINING UP. THIS REGION IS ALSO AT THE
EDGE OF A CAPPING EML. CURRENT EXPECTATIONS ARE THAT THUNDERSTORMS
WILL RAPIDLY DEVELOP IN THIS REGION AROUND 21/22Z AND WILL LIKELY BE
SEVERE GIVEN STRONG INSTABILITY...VERY STEEP MID LEVEL LAPSE RATES
AND DEEP LAYER SHEAR IN EXCESS OF 50 KTS. H85 THETA-E GRADIENT...H7
THERMAL FIELDS AND H85-H3 THICKNESSES ALL POINT TO THIS ACTIVITY
BUILDING SE THROUGH THE NIGHT...WORKING DOWN TO OR EVEN SW OF DES
MOINES THROUGH THE NIGHT. WHAT THIS MEANS FOR THE MPX CWA IS THAT WE
ARE LIKELY TO GET NOTHING MORE THAN A GRAZING FROM THIS
ACTIVITY...WITH THE BEST CHANCES FOR SEEING RAIN BEING SW OF THE MN
RIVER IN SW INTO SC MN. THIS IDEA IS GENERALLY SUPPORTED BY THE NSSL-
WRF AND THE HOP-WRF MEMBERS. THE HRRR SHOWS SOMETHING SIMILAR AS
WELL...THOUGH THINK IT BRINGS ACTIVITY TOO FAR NORTH THROUGH THE
NIGHT.
FOR THE MPX AREA...OUR BEST SHOT AT SEEING PRECIP TONIGHT WILL BE
WITH SOME WEAK ELEVATED THETA-E ADVECTION THAT MAY BE ABLE TO SPARK
SOME ACCUS TYPE ACTIVITY IN WRN MN...BUT WITH THE AMOUNT OF ACTIVITY
EXPECTED TO HEAD FOR IOWA...DO NOT THINK WE WILL SEE MUCH
DEVELOPMENT UP HERE.
FOR SUNDAY...CONFIDENCE IS BEGINNING TO INCREASE THAT WE WILL NOT
SEE ANY ADDITIONAL CONVECTION DURING THE AFTERNOON. THOUGH MOISTURE
AND INSTABILITY SHOULD BE PLENTIFUL WITH DEWPS INCREASING BACK INTO
THE 70S FOR THE SRN HALF OF THE MPX CWA...FORCING WILL BE DECIDEDLY
LACKING. THE BIGGEST ISSUE FOR US IS THAT IN THE WAKE OF ACTIVITY TO
OUR SOUTH OVERNIGHT INTO SUNDAY MORNING...WE WILL HAVE RISING H5
HEIGHTS ALL DAY. IN ADDITION TO THAT...ANY SORT OF WEAK/DIFFUSE WARM
FRONT WILL REMAIN DOWN IN IOWA...SO WE WILL NOT HAVE THAT TO HELP
WITH FORCING DEEP CONVECTION EITHER. IN THE END...RETAINED SOME 30
POPS OR LESS...BUT TRIMMED THAT MENTION DOWN TO ALONG AND SOUTH OF
THE MN RIVER. IN GENERAL THOUGH...SUNDAY LOOKS LIKE A GOOD...THOUGH
WARM/HUMID SUMMER DAY ACROSS THE MPX CWA.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 415 PM CDT SAT JUL 25 2015
THE EVOLUTION OF THE LARGE-SCALE PATTERN THROUGH MONDAY IS THAT OF
BUILDING HEIGHTS AND THE CONTINUATION OF A WARM AND HUMID AIR
MASS THAT SHOULD LINGER INTO TUESDAY...ALTHOUGH THE TEMPERATURE
FORECAST TUESDAY IS COMPLICATED BY THE POSSIBILITY OF CONVECTION.
THE MAIN SURFACE WARM FRONT WILL BE SOUTH AND WEST OF THE FORECAST
AREA ON MONDAY. LOCALLY MN/WI BE SITTING UNDER THE UPPER RIDGE
WITH A MOIST SOUTH-SOUTHEAST BL FLOW BUT NO PRONOUNCED TRIGGER
FOR CONVECTION. 700MB TEMPS AREN`T OVERLY WARM...SO THE CAPPING
ISN`T OVERLY STRONG...THIS IS WHY WE THINK THE GFS TRIES TO
INITIATE CONVECTION OVER THE FORECAST ARE ON MONDAY. THE NAM/ECMWF
ARE DRIER IN MID-LEVELS...SO WE THINK THE POP SHOWERS SHOULD BE
LIMITED MONDAY...ALTHOUGH NOT IMPOSSIBLE EITHER.
ON MONDAY NIGHT INTO TUESDAY MORNING A WARM FRONT LIFT NORTHEAST
INTO THE AREA. THE GUIDANCE SHOWS SCATTERED SHOWERS AND STORMS
ALONG THE FRONT AS IT LIFTS THROUGH. THIS ACTIVITY WILL LIKELY BE
ELEVATED BASED ON FORECAST SOUNDINGS...HOWEVER...PWATS THAT
APPROACH 2" - 2000 J/KG OF MLCAPE - A 13500FT WARM LAYER - AND
FAVORABLE LOW LEVEL SHEAR VECTORS...SUGGEST HEAVY RAIN AND THE
THREAT FOR FLASH FLOODING IS PROBABLY THE BIGGEST HAZARD. THE
925-700MB MOISTURE TRANSPORT LEANS OVER THE FORECAST AREA DURING
THE DAY TUESDAY WITH THE SURFACE TROUGH PASSING THROUGH.
THEREFORE...WE COULD KEEP SHOWERS/STORMS MOST OF THE DAY AND AT
THE VERY LEAST CLOUD COVER COULD MEAN HIGHS ARE CLOSER TO 80 THAN
THE UPPER 80S CURRENTLY IN THE FORECAST. THE SPEED OF THE WARM
FRONTAL PASSAGE IS STILL SOMEWHAT UNCERTAIN...BUT THE MOISTURE
TRANSPORT IS SOLID BY TUESDAY MORNING AT LEAST OFF TODAY`S MODEL
RUNS. THE PRONOUNCED UPPER TROUGH AND BEST DYNAMICS ARE NORTH OF
THE AREA. THE COLD FRONT SHOULD FINALLY CLEAR THE FORECAST AREA
TUESDAY NIGHT...BRINGING IN LESS HUMID AIR WED-FRI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 100 PM CDT SAT JUL 25 2015
UPPER WAVE MOVING IN FROM THE DAKOTAS ATOP HIGH PRESSURE CENTERED
OVER THE TWIN CITIES WILL RESULT IN NOT MUCH MORE THAN MID/UPPER
LEVEL CLOUDS ACROSS THE AREA THROUGH TONIGHT AS LIGHT WINDS
CONTINUE OUT OF THE SSE. EXPECT SEVERE TSRA DEVELOPMENT THIS
AFTERNOON OVER CENTRAL SODAK THAT WILL THEN TRACK ESE TOWARD NRN
IOWA...BUT COULD CLIP RWF...SO LEFT A VCSH MENTION OUT THERE
BETWEEN 4Z AND 10Z.
KMSP...NO POTENTIAL WEATHER CONCERNS UNTIL SUNDAY AFTERNOON...WHEN
A SMALL THREAT FOR THUNDERSTORM DEVELOPMENT EXISTS. WE WILL HAVE
PLENTY OF MOISTURE AND INSTABILITY TO WORK WITH...BUT WILL BE
LACKING FORCING WITH HEIGHTS BUILDING AND ANY SORT OF DIFFUSE WARM
FRONT REMAINING TO THE SOUTH...SO KEPT MSP PRECIP MENTION FREE
THIS TAF PERIOD.
/OUTLOOK FOR KMSP/
MON...VFR. CHC OF TSRA LATE. WINDS SE 5-10 KTS.
TUE...MAINLY VFR. CHC MVFR/IFR IN TSRA. WINDS S 10-15 KTS.
WED...VFR. WINDS W 15-20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
333 PM CDT SAT JUL 25 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 333 PM CDT SAT JUL 25 2015
NEAR TERM MODEL GUIDANCE INDICATES THE POTENTIAL OF A CONVECTIVE
CLUSTER DROPPING SOUTHEAST FROM CENTRAL SOUTH DAKOTA...IMPACTING
ADJACENT PORTIONS OF NORTH CENTRAL NEBRASKA THIS EVENING AND
TONIGHT. LATEST MESOANALYSIS WITH SUPPORT FROM THE 25.18Z NAM
CURRENTLY SUGGESTS A MODERATE TO STRONGLY UNSTABLE ATMOSPHERE...WITH
BETTER THAN 40-45KTS OF DEEP SHEAR FOR STORM ROTATION. IN
ADDITION...THE OPERATIONAL EMC RAP INDICATES ONLY A WEAK CAP
PRESENT. BUT THE MAJORITY OF THE GUIDANCE HOLDS OFF CONVECTION UNTIL
AFTER 06Z TONIGHT ACROSS NORTH CENTRAL NEBRASKA WHEN LOWER
TROPOSPHERIC WAA PROMOTES UPSCALE GROWTH OF STORMS ACROSS SOUTH
CENTRAL SD INTO A MCS. HEAVY RAINFALL MAY BE A CONCERN IF THE
SOLUTION VERIFIES AS PWATS INCREASE IN EXCESS OF 1.75" ACROSS NORTH
CENTRAL NEBRASKA. ELEVATED CAPE OVERNIGHT REMAINS MODERATE TO
STRONGLY UNSTABLE...SO HAIL AND WIND WOULD BE A CONCERN AS WELL.
THERE ARE ADDITIONAL HINTS AT CONVECTION ALONG A WEAK FRONT ACROSS
THE PANHANDLE...WHICH MAY DRIFT EAST INTO THE SANDHILLS REGION THIS
EVENING. ONCE AGAIN...SUFFICIENT CAPE AND SHEAR WOULD PROMOTE
STRONG TO SEVERE STORMS...BUT WARM TEMPERATURES ALOFT MAY CAP
ADDITIONAL DEVELOPMENT.
STORM CHANCES ARE SLIGHT FOR SUNDAY...WITH ONLY A MARGINAL RISK OF
SEVERE WEATHER ACROSS THE EASTERN PANHANDLE AND POSSIBLY WESTERN
SANDHILLS WHERE STEEP LAPSE RATES...2000-3000 J/KG OF SBCAPE AND
30KTS OF 0-6KM SHEAR IS FORECAST TO EXIST. CURRENT THINKING IS THAT
A WEAK DISTURBANCE WILL KICK OFF STORMS ACROSS THE HIGH
PLAINS...LEAVING THE EASTERN PANHANDLE MAINLY DRY THROUGH THE
AFTERNOON.
NUMERICAL GUIDANCE INDICATES A RETURN OF LOWER TO MID-90S ACROSS
MUCH OF THE FORECAST AREA ON SUNDAY...HOWEVER APPARENT TEMPERATURES
ARE NOT FORECAST TO REACH CRITERIA ACROSS OUR ZONES. WILL MONITOR.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 333 PM CDT SAT JUL 25 2015
A SURFACE TROUGH WILL REMAIN LOCATED IN THE EASTERN PANHANDLE
SUNDAY EVENING. DEEP LAYER SHEAR OF 20 TO 30 KTS WOULD BE
SUPPORTIVE OF A FEW STRONG STORMS WEST OF VTN THROUGH BBW.
DUE TO FAIR AGREEMENT BTWN THE NAM AND GFS...INCREASED POPS TO
30-40 PERCENT OVERNIGHT.
MONDAY AND MONDAY NIGHT...THE APPROACHING UPPER TROUGH WILL BRING
STEEP MID LEVEL LAPSE RATES AND A FOCUS FOR STORMS AS A SERIES OF
DISTURBANCE TRACK NORTHEAST FROM COLORADO. A COLD FRONT WILL ALSO
WORK INTO THE NWRN HALF OF THE FA AFTER MIDNIGHT. A FEW STRONG
STORMS AGAIN POSSIBLE ACROSS CNTRL AND EASTERN ZONES.
ON TUESDAY...A COLD FRONT WILL PUSH THROUGH FOR A CHANCE OF
SHOWERS AND THUNDERSTORMS ACROSS THE SERN ZONES. MODELS HAVE
TRENDED FASTER WITH THE FRONT...SO LOWER HIGHS A FEW DEGREES AND
MOVED POPS FURTHER SOUTHEAST AS WELL.
DRY CONDITIONS EXPECTED WEDNESDAY AND WEDNESDAY NIGHT WITH
SURFACE HIGH PRESSURE AND A DRIER AIRMASS IN PLACE. A RETURN OF
MOISTURE IN NW FLOW ALOFT TO BRING AT LEAST A SLIGHT CHANCE BY
THURSDAY...FRIDAY...AND SATURDAY. COVERAGE HOWEVER LOOKS ISOLATED
AT BEST.
TEMPERATURES WILL RANGE FROM 92 TO 98 MONDAY...COOLING TO LOWER
80S NW TO THE UPPER 80S SOUTHEAST ON TUESDAY...THEN MID 80S
WEDNESDAY. THE UPPER 80S ON THURSDAY WILL WARM TO THE LOWER 90S
FRIDAY AND SATURDAY AS THE UPPER RIDGE BECOMES ESTABLISHED IN THE
DESERT SOUTHWEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1221 PM CDT SAT JUL 25 2015
FOR THE 18Z TAF ISSUANCE. FORECAST CONFIDENCE IN WHERE AND WHEN
CONVECTION DEVELOPS THIS AFTERNOON IS LOWER THAN AVERAGE. THAT
BEING SAID...A FEW SHOWERS ARE DEVELOPING TO THE WEST OF
KLBF...WITH A STRONGER THUNDERSTORM OVER KONL. ATTM THE BEST
FOCUS OF ADDITIONAL STORM DEVELOPMENT LOOKS TO LIE TO THE EAST OF
BOTH KLBF AND KVTN THIS AFTERNOON. EASTERN TERMINALS SUCH AS
KANW...KONL...AND/OR KBBW MAY SEE A STRONG OR SEVERE THUNDERSTORM
THIS AFTERNOON. OTHERWISE THE LATEST GUIDANCE INDICATES A 1/4SM
FOG AT KVTN AFTER 09Z SUNDAY MORNING...THIS WAS DISCOUNTED FOR
NOW...BUT WILL BE MONITORED IN FUTURE FORECASTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JACOBS
SHORT TERM...JACOBS
LONG TERM...ROBERG
AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1215 PM CDT SAT JUL 25 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 208 AM CDT SAT JUL 25 2015
MAIN CONCERN WILL REVOLVE AROUND HOW WELL MODELS HANDLE CONVECTIVE
EVENTS TODAY AND TONIGHT...THEN TEMPERATURES AS UPPER RIDGE
REBUILDS ACROSS THE PLAINS REGION.
LAST EVENINGS CONVECTIVE COMPLEX ABOUT TO PUSH EAST OF THE CWA AT
08Z WITH STRONGEST CLUSTER OVER SOUTHWEST IOWA AND EXTREME
SOUTHEAST NEBRASKA. 06Z RAP DOWNPLAYS CONVECTION FOR THE MORNING
PERIOD COMPARED TO NAM OR GFS WITH LATTER MODELS FOCUSING ON A
COMPLEX COMING OUT OF SOUTH DAKOTA. PLAN TO FOLLOW THE RAP TREND
THIS MORNING UNLESS NEW DEVELOPMENT INTENSIFIES TO THE WEST...WITH
POPS INCREASING DURING THE AFTERNOON AND TONIGHT. SOME SMALL
CHANCE OF MAINLY OVERNIGHT CONVECTION SUNDAY NIGHT INTO EARLY
MONDAY BUT WARM MID LEVELS AND STRONGER FLOW TO THE NORTHWEST
AHEAD OF A DEEP UPPER TROUGH WILL HINDER DEVELOPMENT.
CLOUDS AND PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
HOLD TEMPERATURES DOWN TODAY. WARMER TEMPS RETURN FOR SUNDAY AND
MONDAY ALTHOUGH WITH NO SURFACE FRONT IN THE AREA WILL BE LIMITED
TO THE LOWER 90S FOR MOST AREAS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 208 AM CDT SAT JUL 25 2015
NEXT COLD FRONT EXPECTED TO COME INTO THE AREA TUESDAY INTO
TUESDAY NIGHT WITH A BETTER CHANCE OF STORMS FOR THE AREA
ASSOCIATED WITH THE FRONT. SOUTH PARTS OF THE AREA COULD SEE
HOT TEMPERATURES AGAIN IN ADVANCE OF THE FRONT ON TUESDAY.
SOME LINGERING PRECIP IN THE FAR SOUTH ON WEDNESDAY BEFORE FRONT
PUSHES FURTHER SOUTH. DEEP UPPER LOW MOVING ACROSS CANADA WILL DIG
A TROUGH IN THE EAST AND RETROGRADE UPPER HIGH CENTER BACK TO THE
SOUTHWEST PART OF THE NATION WEDNESDAY NIGHT THROUGH FRIDAY WITH
SEASONAL TEMPERATURES EXPECTED DURING THAT TIME.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1213 PM CDT SAT JUL 25 2015
A FEW MORNING SHOWERS AND THUNDERSTORMS ARE STILL MAKING THEIR WAY
THROUGH KOMA AT 18Z. CONDITIONS OUTSIDE OF PRECIP ARE EXPECTED TO
REMAIN VFR...EXCEPT FOR THE POSSIBILITY OF LIGHT FOG AT KOFK EARLY
SUNDAY MORNING. MORE SHOWERS AND THUNDERSTORMS COULD BE POSSIBLE AT
ALL SITES LATER THIS AFTERNOON AND INTO TONIGHT...WITH THE BEST
CHANCE FOR STRONG TO SEVERE STORMS NEAR KOFK. HOWEVER CONFIDENCE
REMAINS VERY LOW AS TO WHEN AND WHERE THEY WILL DEVELOP. THEREFORE
WILL CONTINUE TO MONITOR THE SITUATION AND UPDATE AS NEEDED
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...FOBERT
LONG TERM...FOBERT
AVIATION...KG
AREA FORECAST DISCUSSION
NWS BUFFALO NY
329 PM EDT SAT JUL 25 2015
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TONIGHT AND SUNDAY IN
A HUMID AIR MASS...AS AN UPPER LEVEL DISTURBANCE AND WEAK SURFACE
FRONT CROSS THE AREA. HIGH PRESSURE WILL BRING A RETURN TO DRY
WEATHER AND SEASONABLY WARM TEMPERATURES THROUGH AT LEAST THE MID-
WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
WARM FRONT CONTINUES TO EASE THROUGH CENTRAL NEW YORK THIS
AFTERNOON WITH SOME SCATTERED SHOWERS AFFECTING THE NORTH COUNTRY.
BEHIND THE WARM FRONT...INCREASING HEAT AND HUMIDITY SLOWLY
DESTABILIZING THE ATMOSPHERE WITH MIXED LAYER CAPES NUDGING 1000
J/KG. AT THIS TIME JUST SOME ISOLATED ACTIVITY ON THE NORTHERN
EDGE OF THE LAKE ERIE LAKE SHADOW ACROSS NIAGARA COUNTY. EXPECT WE
WILL SEE ADDITIONAL CONVECTIVE DEVELOPMENT EAST AND SOUTH OF THE
LAKE SHADOW THROUGH THE LATE AFTERNOON.
MORE ORGANIZED CONVECTION NOTED ACROSS SOUTHERN ONTARIO AHEAD OF
UPPER LEVEL SHORTWAVE AND ASSOCIATED WEAK COLD FRONT. THIS
ACTIVITY WILL MAINTAIN ITSELF AND PUSH INTO THE SAINT LAWRENCE
VALLEY AND NORTHERN PORTIONS OF THE NORTH COUNTRY BY LATE
AFTERNOON. THIS ACTIVITY MAY HAVE DIFFICULTY HOLDING TOGETHER
FARTHER SOUTH OVER LAKE ONTARIO.
TONIGHT...EXPECT THE MOST WIDESPREAD ACTIVITY AS THE WEAK FRONT
CROSSES THE REGION THIS EVENING WILL BE FOUND ACROSS THE NORTH
COUNTRY...CLOSEST TO THE CORE OF THE UPPER LEVEL SHORTWAVE.
FORCING WILL BECOME MORE DIFFUSE ACROSS THE REMAINDER OF THE AREA
WITH FORCING RELYING MAINLY ON WEAK SURFACE CONVERGENCE AND
MOISTURE POOLING ALONG THE FRONT. THIS HAS BEEN HINTED AT FOR
SEVERAL RUNS OF THE HRRR AND WRF.
THE ACTIVITY WILL DIMINISH FROM WEST TO EAST OVERNIGHT AS THE
WEAK FRONT PASSES AND DIURNAL INSTABILITY WANES. THERE WILL BE
LITTLE AIR MASS CHANGE BEHIND THE FRONT WITH SURFACE DEWPOINT
REMAINING IN THE 60S. THIS WILL MAINTAIN OVERNIGHT LOWS IN THE
LOWER TO MID 60S.
A TEMPORARY DIP IN THE UPPER HEIGHT FIELDS OVER THE NEXT 24 HOURS
WILL HELP EASE THE ATTENDANT WEAK FRONT INTO THE OHIO VALLEY BY
SUNDAY. POST-FRONTAL ENVIRONMENT SUNDAY WILL BE FOR A SLIGHT
REDUCTION IN HUMIDITY RELATIVE TO TODAY...WITH NO REAL CHANGE
EXPECTED IN THE TEMPERATURES. THE SLIGHTLY DRIER AND MORE STABLE
CONDITIONS AS HIGH PRESSURE SLIDES THROUGH WILL TRANSLATE INTO A
HIGH DEGREE OF SUNSHINE. THIS INSOLATION POTENTIAL INTO A DRIER
AND MODESTLY MIXED PROFILE FAVORS A GREATER DIURNAL TEMPERATURE
RESPONSE...AND WILL BRING HIGHS A COUPLE DEGREES WARMER THAN TODAY
FOR SUNDAY AFTERNOON.
CONVECTIVE ACTIVITY THAT EMERGES SHOULD FOR THE MOST PART REMAIN
SOUTH OF THE AREA CLOSER TO THE FRONTAL BOUNDARY...HOWEVER WITH
INCREASING INSTABILITY ALONG THE SOUTHERN TIER FEEL SOME SCATTERED
ACTIVITY IS NOT OUT OF THE QUESTION...ESPECIALLY SOUTH AND EAST OF
EXPECTED LAKE ERIE LAKE BREEZE.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
DURING THE FIRST HALF OF THIS PERIOD...SURFACE HIGH PRESSURE
INITIALLY ANCHORED OVER THE CENTRAL GREAT LAKES AND OHIO VALLEY
WILL SLOWLY BUILD EASTWARD INTO THE MID ATLANTIC STATES...WHILE A
BROAD NORTHWESTERLY FLOW ALOFT WILL PERSIST IN BETWEEN AN UPPER
LEVEL LOW OVER CENTRAL QUEBEC...AND AN UPPER LEVEL RIDGE AXIS
SLOWLY DRIFTING FROM THE NORTHERN PLAINS STATES INTO THE WESTERN
GREAT LAKES.
FOR THE VAST MAJORITY OF OUR AREA...THE ABOVE WILL RESULT IN
QUIET AND DRY WEATHER THROUGH MONDAY NIGHT. THE ONE POTENTIAL
EXCEPTION TO THIS WILL BE ACROSS THE NORTH COUNTRY AND SAINT
LAWRENCE VALLEY MONDAY AFTERNOON AND EVENING...WHERE THE
COMBINATION OF DAYTIME HEATING...MOISTURE POOLING NORTHEAST OF
LAKE ONTARIO...AND A WEAK SHORTWAVE DROPPING THROUGH THE
PREVAILING NORTHWESTERLY FLOW ALOFT COULD LEAD TO THE DEVELOPMENT
OF SOME ISOLATED TO WIDELY SCATTERED CONVECTION. WITH MORE OF THE
OPERATIONAL GUIDANCE SUITE LATCHING ONTO THIS IDEA OVER THE PAST
24 HOURS...HAVE UPPED POPS FOR THIS REGION/TIMEFRAME UP INTO THE
UPPER PART OF THE SLIGHT CHANCE RANGE.
OTHERWISE...TEMPERATURES WILL REMAIN ON THE WARMER SIDE OF
AVERAGE THROUGH MONDAY NIGHT...WITH SLOW WARMING OF OUR AIRMASS
SUPPORTIVE OF WIDESPREAD HIGHS IN THE MID TO UPPER 80S ON
MONDAY...AND LOWS IN THE UPPER 50S TO MID 60S SUNDAY NIGHT WARMING
A COUPLE OF DEGREES OR SO FOR MONDAY NIGHT. SUCH READINGS WILL BE
ACCOMPANIED BY MODERATELY HUMID CONDITIONS...AS SURFACE DEWPOINTS
WILL RANGE THROUGH THE LOWER HALF OF THE 60S.
AFTER THAT...THE AXIS OF THE AFOREMENTIONED SURFACE RIDGE WILL
DRIFT EASTWARD AND OFF THE ATLANTIC COASTLINE THROUGH
MIDWEEK...WHILE THE AXIS OF ITS PARENT 594 DM UPPER LEVEL RIDGE
BUILDS FROM THE UPPER GREAT LAKES INTO NEW YORK STATE...IN ADVANCE
OF A MID LEVEL TROUGH PUSHING EAST ACROSS CENTRAL CANADA. AS A
RESULT...OUR REGION WILL COME UNDER THE INFLUENCE OF A BROAD
SOUTHWESTERLY FLOW AT THE LOWER LEVELS AND BUILDING
HEIGHTS/INCREASING SUBSIDENCE ALOFT...WITH THE COMBINATION OF
THESE FACTORS LEADING TO HEAT AND HUMIDITY LEVELS STEADILY RISING
ACROSS OUR AREA TUESDAY AND WEDNESDAY.
WITH 850 MB TEMPS CLIMBING TO BETWEEN +17C AND +18C TUESDAY AND
TO THE +19C TO +21C RANGE WEDNESDAY PER A CONSENSUS OF THE
GFS/ECMWF... DAYTIME HIGHS SHOULD EASILY REACH INTO THE 85-90
RANGE AREAWIDE ON TUESDAY AND TO THE UPPER 80S TO LOWER 90S IN
MOST PLACES ON WEDNESDAY...WHEN SOME OF OUR NORMALLY WARMER SPOTS
IN THE GENESEE VALLEY AND FINGER LAKES COULD EVEN SEE MERCURY
LEVELS REACH AS HIGH AS THE MID 90S. AT THE SAME TIME...SURFACE
DEWPOINTS WILL STEADILY CLIMB INTO THE UPPER 60S BY LATER
WEDNESDAY...RESULTING IN HEAT INDICES PUSHING INTO THE LOWER TO
MID 90S AREAWIDE WEDNESDAY AFTERNOON. WHILE SUCH READINGS WOULD
REMAIN SHY OF HEAT ADVISORY CRITERIA...SUCH WARMTH AND HUMIDITY
WILL STILL EASILY MAKE FOR DOWNRIGHT OPPRESSIVE CONDITIONS.
IN TERMS OF PRECIPITATION CHANCES...WHILE A STRAY POP-UP SHOWER
OR THUNDERSTORM OR TWO CANNOT BE COMPLETELY RULED OUT WITH DAYTIME
HEATING OF OUR INCREASINGLY HOT AND HUMID AIRMASS BOTH TUESDAY AND
WEDNESDAY...AT THIS POINT IT STILL APPEARS THAT GENERAL LARGE-
SCALE SUBSIDENCE AND THE LACK OF AN APPRECIABLE TRIGGER SHOULD
KEEP OUR WEATHER MAINLY DRY THROUGH THE VAST MAJORITY OF THE DAY
ON WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
EARLY ON IN THIS PERIOD...THE MEDIUM RANGE GUIDANCE REMAINS IN
GOOD AGREEMENT ON THE NEXT MID LEVEL TROUGH SLIDING EAST ACROSS
CENTRAL CANADA...WHILE PUSHING ITS ATTENDANT COLD FRONT ACROSS OUR
REGION BETWEEN LATER WEDNESDAY NIGHT AND THURSDAY. IN THE
PROCESS...THIS FEATURE SHOULD GENERATE AT LEAST SOME SCATTERED
CONVECTION AS IT INTERACTS WITH THE HOT AND STICKY ANTECEDENT
AIRMASS THAT WILL BE IN PLACE ACROSS OUR REGION.
FOLLOWING THE PASSAGE OF THE COLD FRONT...HIGH PRESSURE AND
COOLER/DRIER AIR THEN LOOKS TO BUILD EAST ACROSS OUR REGION
BETWEEN THURSDAY AFTERNOON AND FRIDAY...WHILE USHERING IN A RETURN
TO DRY WEATHER AND MORE COMFORTABLE TEMPERATURES AND HUMIDITY
LEVELS.
FINALLY AS WE GET INTO NEXT WEEKEND...MAINLY DRY WEATHER SHOULD
CONTINUE ON SATURDAY IN ADVANCE OF THE NEXT BROAD MID LEVEL TROUGH
AND ITS ASSOCIATED WEAK COLD FRONT...ALONG WITH A LITTLE BUMP
UPWARD IN TEMPERATURES AGAIN AS SLIGHTLY WARMER AIR GETS ADVECTED
INTO OUR REGION IN ADVANCE OF THIS NEXT SYSTEM.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
SCATTERED -SHRA CONTINUE TO TRACK ESE ACROSS CNY AS A WARM FRONT
PUSHES EAST ACROSS THE AREA. ACTIVITY HAS SHIFTED TO THE EAST OF
ALL TERMINALS. VFR CONDITIONS WILL PREVAIL THROUGH THE REST OF THE
AFTERNOON.
MID-LEVEL TROUGH AXIS AND ASSOCIATED WEAK SURFACE FRONTAL
BOUNDARY WILL CROSS THE FORECAST AREA THIS EVENING. THIS FEATURE
MAY GENERATE MORE WIDESPREAD -SHRA/TSRA...PARTICULARLY ACROSS THE
NORTH COUNTRY...CLOSER TO THE STRONGER UPPER LEVEL FORCING.
ACTIVITY WILL TAPER OFF FROM W-E AFTER 06Z WITH THE PASSAGE OF THE
FRONT.
OUTLOOK...
SUNDAY...MAINLY VFR WITH A CHANCE OF AFTERNOON SHOWERS AND
THUNDERSTORMS INLAND FROM THE LAKES.
SUNDAY NIGHT...MAINLY VFR WITH A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS.
MONDAY THROUGH THURSDAY...VFR.
&&
.MARINE...
WINDS AND WAVES WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA
THROUGH SUNDAY NIGHT DESPITE THE PASSAGE OF A COLD FRONT TONIGHT.
THUNDERSTORMS ARE POSSIBLE WHILE THE COLD FRONT MOVES ACROSS OUR
NEARSHORE AREAS...BUT STRONG/SEVERE STORMS ARE NOT EXPECTED. HIGH
PRESSURE THEN RETURNS MONDAY WITH GENERALLY CALM CONDITIONS
PERSISTING INTO THE MIDDLE OF THE COMING WEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1235 PM CDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 1235 PM CDT SAT JUL 25 2015
MADE SOME FURTHER ADJUSTMENTS TO POPS AS MORE WEAK CONVECTION HAS
POSSPED UP JUST EAST OF THE RED RIVER AND STARTED TO MOVE
EASTWARD. ADDITIONAL CONVECTION HAS STARTED NEAR THE SOUTHWESTERN
COUNTIES BUT JUST WILL KEEP SOME LOW POPS IN THAT AREA FOR NOW DUE
TO UNCERTAINTY IN HOW FAR NORTHEASTWARD THE CONVECTION DEVELOPS.
LOWERED TEMPS JUST A BIT IN THE SOUTHERN AND EASTERN CWA WITH
CLOUD COVER AND POSSIBILITY OF PRECIP. THINK THAT SOME SPOTS COULD
STILL APPROACH 90 AND IT WILL CONTINUE TO BE HUMID WITH DEW POINTS
IN THE UPPER 60S.
UPDATE ISSUED AT 933 AM CDT SAT JUL 25 2015
A FEW SHOWERS HAVE STARTED TO GO UP IN THE NORTHERN VALLEY AS A
WEAK SHORTWAVE HAS BEEN GOING OVER THE TOP OVER THE TOP OF THE
RIDGE. BUMPED UP POPS TO SCATTERED IN THIS AREA AND HAVE IT MOVING
EASTWARD FOR THE REST OF THE DAY. SO FAR IT IS MOSTLY SHOWERS BUT
SOME LIGHTNING IS NOT OF THE QUESTION WITH 1000 J/KG OF ELEVATED
CAPE. THINK THAT THE SHOWERS AND CLOUDS WILL NOT KEEP US FROM
GETTING INTO THE UPPER 80S THIS AFTERNOON AT THIS POINT...BUT
WILL MONITOR.
UPDATE ISSUED AT 641 AM CDT SAT JUL 25 2015
CONVECTION THAT BLEW UP OVER NORTHWESTERN SD IS RESULTING IN
CIRRUS BLOW OFF SPREADING ACROSS SRN ND AND INTO SWRN ZONES. WILL
INCREASE SKY COVER FOR MORNING HOURS ACROSS THE SOUTH. ALSO PATCHY
CLOUDS OVER NORTHERN VALLEY MORE BKN THAN EXPECTED THIS
MORNING...AND WILL ADJUST SKY FOR THIS REGION AS WELL. HI RES
MODELS CONTINUE TO DIFFER WITH CONVECTION ACROSS MAINLY THE
NORTH. CONFIDENCE TOO LOW TO ADD ANY POPS OTHER THAN THE FAR
NORTHEAST...WHICH HAS BEEN A BIT MORE CONSISTENT. NO OTHER CHANGES
PLANNED THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
FORECAST CHALLENGE FOR THE SHORT TERM WILL BE POTENTIAL FOR
CONVECTION MAINLY ACROSS THE SOUTH AND DAYTIME HIGHS FOR WHAT
SHOULD BE A GENERALLY DRY WEEKEND. PREFER HIGHER RES MODELS FOR
PRECIP TRENDS THIS EVENING. A RIDGE AXIS IS CURRENTLY OVER THE
EASTERN CWA...BRINGING CALM WINDS TO MOST OF WEST CENTRAL
MINNESOTA WHILE WEAK RETURN FLOW HAS SET UP OVER EASTERN NORTH
DAKOTA AND THE NORTHERN VALLEY TO INCLUDE FAR NORTHWESTERN MN.
THIS MORNING...CALM WINDS...DEW POINTS AROUND 60 AND CLEAR SKIES
ARE RESULTING IN SOME PATCHY FOG ACROSS W CNTRL MN. HAVE PUT
PATCHY FOG INTO FCST THROUGH 13Z TO 14Z TIMEFRAME. MAY SEE SOME
IMPROVEMENT ADJACENT TO THE VALLEY AS WINDS PICK UP AND TURN
SOUTHERLY...BUT SHOULD HOLD OFF UNTIL MID MORNING BURN OFF IN
EASTERN ZONES.
RETURN FLOW WILL SET UP AND WESTERN ZONES SHOULD SEE SOME
INCREASED INSTABILITY...HOWEVER THE BEST INSTABILITY WILL
GENERALLY BE ACROSS WRN ND AND SD WITH WEAK SUBSIDENCE OVER OUR
AREA AS LOW AMPLITUDE UPPER RIDGE MOVES ACROSS AREA. MODELS ARE
SHOWING WEAK SHORTWAVES CONTINUING TO RIDE NORTHERN EDGE OF THE
UPPER RIDGE AND DEVELOP CONVECTION ACROSS SRN MANITOBA WILE A
STRONGER WAVE WILL MOVE ACROSS SD WHERE SPC HAS A SLIGHT RISK FOR
DAY 1. DEEP LAYER SHEAR CURRENTLY AROUND 40 KTS WILL WEAKEN
THROUGH THE DAY AS UPPER RIDGE MOVES ACROSS ND...WHILE WRN ND WILL
SEE AN INCREASE IN INSTABILITY BY LATE AFTN. THINK BEST CHANCE FOR
STORMS WILL BE ALONG SD BORDER OR WRN ZONES WHERE STORMS
DEVELOPING OVER WRN/CNTRL ND AND ADVECT INTO DVL AREA. ECMWF/GFS
APPEAR RATHER BULLISH FOR CONVECTION IN FAR WRN ND BUT MOST MODELS
IN AGREEMENT WITH CONVECTION DYING OFF OVERNIGHT. WILL KEEP LOW
CHANCE POPS IN THE FAR WEST/SOUTH WITH MAJORITY OF CWA DRY. ALSO
ADDED LOW POPS IN THE FAR NORTHEAST AS HRRR CONTINUES TO SHOW SOME
WEAK STORMS RIDING OVER THE RIDGE AND CROSS LAKE OF THE
WOODS...NORTHERN BELTRAMI COUNTIES.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 403 AM CDT SAT JUL 25 2015
SUNDAY NIGHT INTO MONDAY...UPPER RIDGE OVER EASTERN ZONES WHILE
WE SLOWLY TRANSITION FROM A MORE ZONAL TO SOUTHWESTERLY FLOW
PATTERN IN THE WEST BY 00Z MON. SHOULD SEE PLENTY OF SUNSHINE AND
TEMPS AROUND 90 F FOR DAYTIME HIGHS BOTH DAYS. WILL SEE CONVECTION
BEGIN TO DEVELOP OVER ERN MT AND WRN ND LATE IN THE DAY...MOSTLY
DRY OVER OUR AREA. WEAK LOW PRESSURE OVER SASK/MB REGION WILL
INTERACT WITH A SERIES OF WEAK SHORT WAVES EMBEDDED IN SW
FLOW...AND BRING A CHANCE FOR TSTMS TO NW ZONES AND ALONG THE INTL
BORDER. A MORE SIGNIFICANT LOW PRESSURE SYSTEM THEN DEVELOPS MON
NIGHT OVER MT/WY AND WILL BRING A FRONT ACROSS THE AREA EARLY IN
THE NEXT WORK WEEK. HAVE CONTINUED LIKELY POPS IN THE FAR
NORTHWESTERN ZONES AS STORMS CONTINUE ACROSS SRN CANADA.
FOR TUE THROUGH FRI...THERE COULD BE SOME CONVECTION ON TUE
DEPENDING ON TIMING OF A FRONT THAT WILL MOVE THROUGH THE AREA.
THEREAFTER...TEMPS SHOULD COOL DOWN BELOW NORMAL BY WED. THERE COULD
BE SOME CONVECTION IN THE NORTH WED CLOSER TO CYCLONIC FLOW...BUT
OVERALL NOT EXPECTING TOO MUCH COVERAGE OF SHOWERS OR STORMS. FOR
THU/FRI...EXPECT TEMPS RISING TO AROUND NORMAL WITH MAINLY DRY
WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1235 PM CDT SAT JUL 25 2015
SOUTHERLY WINDS CLOSE TO 10 KTS THROUGH THE EVENING AT ALL
SITES...DIMINISHING OVERNIGHT. OTHERWISE VFR CONDITIONS EXPECTED
THROUGH SUNDAY MORNING. LOW CONFIDENCE IN COVERAGE AND DURATION OF
SOME RW/TRW ACTIVITY LATER TONIGHT PRECLUDES INCLUSION IN TAFS AT
THE PRESENT TIME. ENOUGH ACTIVITY OVER NW MN PRESENTLY FOR A TEMPO
MENTION AT KBJI THIS AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...SPEICHER
LONG TERM...DK/SPEICHER
AVIATION...WJB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1201 PM CDT SAT JUL 25 2015
.UPDATE...
ISSUED AT 1150 AM CDT SAT JUL 25 2015
SHORT LINE OF THUNDERSTORMS INITIATED ALONG AN OUTFLOW BOUNDARY IN
SOUTH CENTRAL NORTH DAKOTA FROM AN OUTFLOW BOUNDARY FROM EARLIER
CONVECTION ALONG ND/SD BORDER. VERY SMALL SCALE AND DO NOT HAVE A
GOOD GRASP ON THE FUTURE TREND YET. WILL ADD THUNDERSTORMS
BETWEEN BISMARCK AND JAMESTOWN FOR THIS AFTERNOON.
UPDATE ISSUED AT 941 AM CDT SAT JUL 25 2015
MCS ACROSS THE ND/SD BORDER DIURNALLY TRENDING DOWN THIS MORNING
WITH THE CLOUD SHIELD DIMINISHING. SO DID SOME CLOUD AND POP
UPDATES THIS MORNING. TRIMMED POPS BACK JAMES RIVER VALLEY WEST
TO THE MISSOURI RIVER THROUGH EARLY AFTERNOON.
UPDATE ISSUED AT 559 AM CDT SAT JUL 25 2015
QUICK UPDATE TO LOWER POPS AND CONFINE ISOLATED SHOWERS AND
THUNDERSTORMS TO THE FAR SOUTH THROUGH THE MORNING HOURS. THE
RAP13 APPEARS TO HAVE A MUCH BETTER HANDLE THAN THE HRRR IN TERMS
OF MOVING/DEVELOPING AN AREA OF THUNDERSTORMS IN NORTHWESTERN
SOUTH DAKOTA. EARLIER IT APPEARED THAT THIS WOULD MOVE STEADILY
NORTHEAST BUT LATEST TRENDS SUGGEST A MORE EASTWARD MOVEMENT. THIS
WILL LIMIT POPS ACROSS SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA.
IR CLOUDS TOP TEMPS OF -54C REPRESENTS A CIRRUS SHIELD WITH HEIGHTS
BETWEEN 30KFT AND 35KFT. UPDATES FORTHCOMING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM CDT SAT JUL 25 2015
THE LATEST WATER VAPOR IMAGERY SHOWS A SOUTHWEST FLOW INTO
WESTERN AND CENTRAL NORTH DAKOTA WITH A FEW EMBEDDED MID LEVEL
SHORTWAVE TROUGHS. THESE SHORTWAVE TROUGHS WERE LOCATED IN
SOUTHEAST MONTANA...NORTHERN WYOMING...AND WESTERN SOUTH DAKOTA.
REGIONAL RADAR SHOWING A GROWING AREA OF SHOWERS AND THUNDERSTORMS
OVER SOUTHEAST MONTANA INTO CENTRAL AND NORTHERN SOUTH DAKOTA.
BOWMAN RADAR ALSO DEPICTS THE LEADING EDGE OF LIGHT SHOWERS
SCOOTING OVER THE FAR SOUTHWEST. MAIN THEME TODAY WILL BE ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS OVER SOUTHWEST NORTH DAKOTA
EARLY THIS MORNING...CONTINUING DURING THE DAY...AND GRADUALLY
EXPANDING INTO CENTRAL NORTH DAKOTA THROUGH THE AFTERNOON AND
EARLY EVENING. ALTHOUGH THE GFS/ECMWF KEEP THE MAXIMUM CAPE AND
0-6KM SHEAR DISPLACED FROM EACH OTHER...VALUES ARE STILL HIGH
ENOUGH FOR THE AFOREMENTIONED SHORTWAVES TO WORK WITH RESULTING IN
STRONG TO ISOLATED SEVERE THUNDERSTORMS TODAY...ESPECIALLY ACROSS
THE SOUTH. SPC HAS THE SLIGHT RISK AREA APPROACHING OUR SOUTHERN
BORDER TODAY WITH MARGINAL CRITERIA COVERING ALL EXCEPT THE FAR
NORTHWEST. THE SHOWERS/THUNDERSTORMS WILL MAINLY RESIDE ACROSS THE
JAMES RIVER VALLEY SATURDAY EVENING/NIGHT AS THE SHORTWAVES
MIGRATE EAST. AFTERNOON HIGHS TODAY WILL REACH WELL INTO THE
80S...WITH LOWER 90S IN THE NORTHWEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 415 AM CDT SAT JUL 25 2015
ZONAL MID LEVEL FLOW IN THE SHORT TERM TRANSITIONS TO SOUTHWEST
FLOW AS THE WEST COAST TROUGH DEEPENS...AND THEN BEGINS TO PUSH
OVER THE ROCKIES MONDAY. WEAK WAVES IN THE FLOW INTO MONDAY KEEP
LOWER POPS IN THE FORECAST FOR EACH DAY. BY MONDAY...AS THE LONG
WAVE TROUGH APPROACHES...SURFACE LOW PRESSURE OVER EASTERN MONTANA
INTENSIFY WITH STRONG WARM AIR AND MOISTURE ADVECTION INTO
WESTERN NORTH DAKOTA...TEMPERATURES SOLIDLY INTO THE MID 90S...AND
WIND SPEEDS APPROACHING ADVISORY THRESHOLDS.
SEVERE WEATHER PARAMETERS BECOME MORE FAVORABLE LATER MONDAY DUE
IN PART TO THE INCREASING MOISTURE...BUT ALSO IN THE BREAK OUT OF
SUNSHINE IN A CLEAR SLOT...AND NEAR THE FRONTAL TRIPLE POINT.
VERY STRONG THERMODYNAMICS SHOULD ALSO BE PRESENT ACROSS THE
POWERFUL COLD FRONT...FURTHER ENHANCING STORMS. SEVERE STORMS
WILL BE POSSIBLE MONDAY AND MONDAY NIGHT.
FOR TUESDAY A SIGNIFICANT COOL DOWN IS PREDICTED WITH HIGHS IN THE
NORTHWEST PART OF NORTH DAKOTA ONLY REACHING AROUND 70 BEHIND THE
ANOMALOUSLY DEEP SYSTEM...FOR THE END OF JULY...MOVING THROUGH
SOUTHERN SASKATCHEWAN. EXPECT GUSTY WINDS.
DRY FOR THE MIDDLE TO LATTER PARTS OF NEXT WEEK WITH HIGHS MAINLY
IN THE 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1150 AM CDT SAT JUL 25 2015
SURFACE TROUGH ACROSS EASTERN MONTANA INTO SOUTHWEST NORTH DAKOTA
SATURDAY MORNING WILL BE THE FOCUS FOR SCATTERED THUNDERSTORMS
ACROSS MOST OF WEST AND CENTRAL NORTH DAKOTA THROUGH SUNDAY
MORNING. WILL CONTINUE USING VICINITY FOR THE THUNDERSTORM
THREAT. OTHERWISE VFR AT ALL TAF SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...JPM
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
701 PM EDT SAT JUL 25 2015
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL DROP SOUTH INTO THE AREA TONIGHT
INTO SUNDAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. THE
BOUNDARY AND THUNDERSTORM CHANCES WILL SHIFT TOWARD THE SOUTH ON
MONDAY. WEAK HIGH PRESSURE AND A VERY WARM AIRMASS ARE EXPECTED
FOR TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HIGH PRESSURE REMAINS CENTERED TO THE EAST WHILE A WEAK COLD FRONT
STRETCHES FROM MICHIGAN TO ILLINOIS. LITTLE TO NO SHOWER OR
THUNDERSTORM ACTIVITY IS EVIDENT AT THIS HOUR ALONG THE FRONT.
AS THE FRONT MOVES TO THE ILN AREA TONIGHT...CONVERGENCE AND
INCREASING MOISTURE ASSOCIATED WITH THE FRONT MAY STILL RESULT IN
A FEW SHOWERS AS SUGGESTED BY THE RAP MODEL...THOUGH ANY SHOWERS
THAT DEVELOP WILL BE MOVING EAST INTO LESS FAVORABLE INSTABILITY
CLOSER TO THE HIGH CENTER. UNDER PARTLY TO MOSTLY CLOUDY SKIES IN
A HUMID AIRMASS...LOWS WILL STAY UP AROUND 70.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS THE FRONT SAGS SLOWLY SOUTHEAST ACROSS THE AREA ON
SUNDAY...SHOWERS AND THUNDERSTORMS MAY DEVELOP PRIMARILY IN THE
AFTERNOON ALIGNED ROUGHLY ALONG I-71. SEVERE THUNDERSTORMS ARE
UNLIKELY IN AN ENVIRONMENT OF MODERATE CAPE BUT WEAK WIND FIELDS.
FOR MONDAY...THE FRONT IS FORECAST TO PROGRESS TO THE VICINITY OF
THE OHIO RIVER...WHILE HIGH PRESSURE DROPS TO NORTHERN OHIO.
SHOWERS AND THUNDERSTORMS MAY FORM AGAIN MONDAY AFTERNOON...MAINLY
IN SOUTHERN LOCATIONS CLOSE TO THE FRONT. NORTHERN LOCATIONS
SHOULD BE PROTECTED FROM PRECIP BY THE DRIER AIRMASS ASSOCIATED
WITH THE HIGH PRESSURE.
NEAR NORMAL HIGHS IN THE MID AND UPPER 80S ARE EXPECTED.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
MID LEVEL RIDGING CENTERED OVER THE NATIONS MID SECTION TO BUILD
NORTHEAST INTO THE OHIO VALLEY/GREAT LAKES REGION TUESDAY.
HEIGHT/THICKNESS RISES WILL LEAD TO A WARM UP OF TEMPERATURES...WITH
HIGHS ON TUESDAY IN THE UPPER 80S TO AROUND 90 DEGREES. BEST
MOISTURE/LIFT LOOKS TO BE TO OUR SW BUT A STRAY STORM IS NOT OUT OF
THE QUESTION DURG THE AFTN. DUE TO THE LACK OF SIGNIFICANT FORCING
HAVE OPTED TO GO WITH DRY FCST.
NRN PORTION OF MID LEVEL RIDGE TO BECOME FLATTENED AS TROF MOVES
THRU SRN CANADA/NRN PLAINS INTO THE GREAT LAKES AT MID WEEK. THIS
WILL ALLOW A SFC COLD FRONT TO PUSH THRU THE REGION EARLY THURSDAY.
HAVE INCLUDED MENTION OF LOW CHANCE POPS FOR THUNDERSTORMS WED AFTN
AS MOISTURE AND MODERATE INSTBY RETURNS. WARM TEMPERATURES TO
CONTINUE WEDNESDAY AHEAD OF THE FRONT WITH HIGHS FROM THE UPPER 80S
NW TO THE LOWER 90S SE.
THUNDERSTORM CHANCES INCREASE WEDNESDAY NIGHT INTO EARLY THURSDAY AS
THE FRONT APPROACHES. AS SFC HIGH PRESSURE BEGINS TO NOSE IN
THURSDAY...DRY CONDITIONS WILL RETURN. TEMPERATURES WILL BE A LTL
COOLER WITH HIGHS FROM THE MID 80S NW TO THE UPPER 80S SE.
NORTHWEST FLOW ALOFT WITH SFC HIGH PRESSURE BUILDING ACRS THE REGION
LATE IN THE WEEK INTO NEXT WEEKEND. HAVE HELD OFF ON ANY MENTION OF
PCPN THRU SATURDAY. TEMPERATURES ON BOTH FRIDAY AND SATURDAY WILL
CLOSE TO NORMAL WITH HIGHS IN THE LOWER AND MIDDLE 80S.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A WEAK COLD FRONT STRETCHED FROM SOUTHERN ONTARIO...SOUTHWEST
TO SOUTHEAST MICHIGAN...FAR NORTHERN INDIANA AND NORTHERN
ILLINOIS THIS EVENING. THIS BOUNDARY WILL SLOWLY DRIFT SOUTHEAST
INTO THE NORTHERN SECTIONS OF THE FORECAST AREA OVERNIGHT. WITH
THE LOSS OF DAYTIME HEATING AND WEAK CONVERGENCE/UPPER LEVEL
SUPPORT...ONLY A 20 PERCENT CHANCE OF A SHOWER IS EXPECTED NEAR
THE NORTHERN TAF SITES AFTER 06Z. IN ADDITION..WINDS WILL EITHER
BE CALM OR FAIRLY LIGHT...SO SOME MIST WILL DEVELOP TOWARD MORNING
AS LOW LEVEL MOISTURE INCREASES WITH NOCTURNAL COOLING AHEAD OF
THE FRONT. THE EXCEPTION WILL BE KLUK WHERE SOME IFR VISIBILITIES
MAY OCCUR. IMPROVEMENT TO VISIBILITIES WILL OCCUR BETWEEN 12Z AND
14Z.
ON SUNDAY...FRONTAL BOUNDARY WILL SLOWLY SINK SOUTH. DIURNAL
HEATING WILL ALLOW FOR MAINLY A 30 PERCENT CHANCE OF SHOWERS AND
THUNDERSTORMS ALONG THE BOUNDARY. GIVEN THE DISORGANIZED NATURE
AND LOW PROBABILITY OF PRECIPITATION...HAVE JUST INCLUDED VCSH
DESCRIPTORS AT THE TAF SITES.
OUTLOOK...THUNDERSTORMS POSSIBLE WEDNESDAY NIGHT INTO THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO
SHORT TERM...CONIGLIO
LONG TERM...AR
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
417 PM EDT SAT JUL 25 2015
.SYNOPSIS...
A WEAK FRONTAL BOUNDARY WILL DROP SOUTH INTO THE AREA TONIGHT
INTO SUNDAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. THE
BOUNDARY AND THUNDERSTORM CHANCES WILL SHIFT TOWARD THE SOUTH ON
MONDAY. WEAK HIGH PRESSURE AND A VERY WARM AIRMASS ARE EXPECTED
FOR TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HIGH PRESSURE REMAINS CENTERED TO THE EAST WHILE A WEAK COLD FRONT
STRETCHES FROM MICHIGAN TO ILLINOIS. LITTLE TO NO SHOWER OR
THUNDERSTORM ACTIVITY IS EVIDENT AT THIS HOUR ALONG THE FRONT.
AS THE FRONT MOVES TO THE ILN AREA TONIGHT...CONVERGENCE AND
INCREASING MOISTURE ASSOCIATED WITH THE FRONT MAY STILL RESULT IN
A FEW SHOWERS AS SUGGESTED BY THE RAP MODEL...THOUGH ANY SHOWERS
THAT DEVELOP WILL BE MOVING EAST INTO LESS FAVORABLE INSTABILITY
CLOSER TO THE HIGH CENTER. UNDER PARTLY TO MOSTLY CLOUDY SKIES IN
A HUMID AIRMASS...LOWS WILL STAY UP AROUND 70.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS THE FRONT SAGS SLOWLY SOUTHEAST ACROSS THE AREA ON
SUNDAY...SHOWERS AND THUNDERSTORMS MAY DEVELOP PRIMARILY IN THE
AFTERNOON ALIGNED ROUGHLY ALONG I-71. SEVERE THUNDERSTORMS ARE
UNLIKELY IN AN ENVIRONMENT OF MODERATE CAPE BUT WEAK WIND FIELDS.
FOR MONDAY...THE FRONT IS FORECAST TO PROGRESS TO THE VICINITY OF
THE OHIO RIVER...WHILE HIGH PRESSURE DROPS TO NORTHERN OHIO.
SHOWERS AND THUNDERSTORMS MAY FORM AGAIN MONDAY AFTERNOON...MAINLY
IN SOUTHERN LOCATIONS CLOSE TO THE FRONT. NORTHERN LOCATIONS
SHOULD BE PROTECTED FROM PRECIP BY THE DRIER AIRMASS ASSOCIATED
WITH THE HIGH PRESSURE.
NEAR NORMAL HIGHS IN THE MID AND UPPER 80S ARE EXPECTED.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
MID LEVEL RIDGING CENTERED OVER THE NATIONS MID SECTION TO BUILD
NORTHEAST INTO THE OHIO VALLEY/GREAT LAKES REGION TUESDAY.
HEIGHT/THICKNESS RISES WILL LEAD TO A WARM UP OF TEMPERATURES...WITH
HIGHS ON TUESDAY IN THE UPPER 80S TO AROUND 90 DEGREES. BEST
MOISTURE/LIFT LOOKS TO BE TO OUR SW BUT A STRAY STORM IS NOT OUT OF
THE QUESTION DURG THE AFTN. DUE TO THE LACK OF SIGNIFICANT FORCING
HAVE OPTED TO GO WITH DRY FCST.
NRN PORTION OF MID LEVEL RIDGE TO BECOME FLATTENED AS TROF MOVES
THRU SRN CANADA/NRN PLAINS INTO THE GREAT LAKES AT MID WEEK. THIS
WILL ALLOW A SFC COLD FRONT TO PUSH THRU THE REGION EARLY THURSDAY.
HAVE INCLUDED MENTION OF LOW CHANCE POPS FOR THUNDERSTORMS WED AFTN
AS MOISTURE AND MODERATE INSTBY RETURNS. WARM TEMPERATURES TO
CONTINUE WEDNESDAY AHEAD OF THE FRONT WITH HIGHS FROM THE UPPER 80S
NW TO THE LOWER 90S SE.
THUNDERSTORM CHANCES INCREASE WEDNESDAY NIGHT INTO EARLY THURSDAY AS
THE FRONT APPROACHES. AS SFC HIGH PRESSURE BEGINS TO NOSE IN
THURSDAY...DRY CONDITIONS WILL RETURN. TEMPERATURES WILL BE A LTL
COOLER WITH HIGHS FROM THE MID 80S NW TO THE UPPER 80S SE.
NORTHWEST FLOW ALOFT WITH SFC HIGH PRESSURE BUILDING ACRS THE REGION
LATE IN THE WEEK INTO NEXT WEEKEND. HAVE HELD OFF ON ANY MENTION OF
PCPN THRU SATURDAY. TEMPERATURES ON BOTH FRIDAY AND SATURDAY WILL
CLOSE TO NORMAL WITH HIGHS IN THE LOWER AND MIDDLE 80S.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
A MIX OF VFR CLOUD LAYERS WILL MOVE THROUGH THE REGION
TODAY...WITH GENERALLY LIGHT SOUTHWESTERLY FLOW. A FEW SHOWERS AND
STORMS WILL LIKELY DEVELOP IN NORTHERN INDIANA AND NORTHWEST OHIO
LATE THIS AFTERNOON...BUT THIS ACTIVITY CURRENTLY APPEARS UNLIKELY
TO AFFECT ANY OF THE TAF SITES.
MVFR VISIBILITIES APPEAR LIKELY FOR ALL TAF SITES OVERNIGHT...WITH
THE POTENTIAL FOR IFR CONDITIONS AT KLUK.
ON SUNDAY...A COLD FRONT WILL SLOWLY MOVE SOUTH THROUGH THE
REGION. WINDS WILL BE LIGHT ON EITHER SIDE OF THE FRONT...BUT WILL
EVENTUALLY SHIFT TO THE NORTH AFTER THE FRONT PASSES. THERE WILL
BE A VERY SMALL CHANCE OF PRECIPITATION AT ANY TIME SUNDAY
MORNING...BUT IT IS MORE LIKELY THAT MOST OF THE EXPECTED SHOWER
AND THUNDERSTORM ACTIVITY WILL DEVELOP AFTER 17Z.
OUTLOOK...SHOWERS AND THUNDERSTORMS ARE POSSIBLE WEDNESDAY NIGHT
INTO THURSDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO
SHORT TERM...CONIGLIO
LONG TERM...AR
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS TULSA OK
1221 PM CDT SAT JUL 25 2015
.DISCUSSION...
THE 18Z TAF DISCUSSION IS INCLUDED BELOW.
&&
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR CONDITIONS WILL PREVAIL BENEATH HIGH PRESSURE ALOFT. ISOLATED
AFTERNOON TSRA OVER IN WRN AR WILL LIKELY BE EAST OF THE TERMINALS
SO NO MENTION WAS INCLUDED IN THE TAFS.
LACY
&&
.PREV DISCUSSION... /ISSUED 1017 AM CDT SAT JUL 25 2015/
DISCUSSION...
MORNING UPPER AIR DATA SUGGESTS THAT THE MID LEVEL RIDGE HAS
WEAKENED A LITTLE OVER OKLAHOMA AND ARKANSAS COMPARED TO
YESTERDAY. BOTH THE NAM AND HRRR SUGGEST AT LEAST ISOLATED STORM
DEVELOPMENT OVER ARKANSAS THIS AFTERNOON...MAINLY TO THE EAST OF
THE TULSA WFO FORECAST AREA WHERE 500MB ARE COOLER AND HEIGHTS ARE
LOWER. THERE IS ENOUGH OF A CONSISTENT SIGNAL IN THE AVAILABLE
DATA TO INSERT A SLIGHT CHANCE OF AFTERNOON STORMS EAST OF THE
I-49 CORRIDOR IN NORTHWEST ARKANSAS. NO OTHER CHANGES WERE NEEDED.
HEAT HEADLINES REMAIN INTACT.
LACY
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 99 77 99 77 / 0 0 10 0
FSM 99 77 99 77 / 10 0 0 0
MLC 97 73 97 73 / 0 0 0 0
BVO 97 73 97 73 / 0 0 10 0
FYV 94 71 94 71 / 10 0 0 0
BYV 94 72 94 72 / 20 0 10 10
MKO 95 74 95 74 / 0 0 0 0
MIO 96 74 96 74 / 10 0 10 0
F10 96 74 96 74 / 0 0 0 0
HHW 97 74 97 74 / 0 0 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR OKZ049-053-063-068-
069-073-075.
EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR
OKZ054>062-064>067-070>072-074-076.
AR...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ARZ001-002-010-011.
EXCESSIVE HEAT WARNING UNTIL 8 PM CDT THIS EVENING FOR ARZ019-
020-029.
&&
$$
AVIATION...30
AREA FORECAST DISCUSSION
NWS PORTLAND OR
905 AM PDT SAT JUL 25 2015
.SYNOPSIS...THE REMAINS OF A WEAK COLD FRONT OVER WESTERN WASHINGTON
AND NORTHWEST OREGON EARLY THIS MORNING WILL CONTINUE TO DRIFT EAST
TODAY. AN UPPER LEVEL TROUGH WILL DEEPEN SATURDAY NIGHT AND
SUNDAY...WHICH WILL INCREASE THE CHANCES OF PRECIPITATION. THERE WILL
ALSO BE A THREAT OF THUNDERSTORMS OVER THE NORTHERN INLAND AREAS
SUNDAY AFTERNOON AS THE COLD POOL ASSOCIATED WITH THE UPPER TROUGH
MOVES INTO THE AREA. THE UPPER TROUGH EXITS TO THE EAST MONDAY...
WHICH WILL MARK THE BEGINNING OF A RAPID WARMING AND DRYING TREND.
THERE IS THE POTENTIAL FOR LIGHT OFFSHORE LOW-LEVEL FLOW TO DEVELOP
TUESDAY AND WEDNESDAY...HELPING TO BOOST DAYTIME TEMPERATURES WELL
ABOVE NORMAL.
&&
.UPDATE...DOPPLER RADAR AND SURFACE OBSERVATIONS INDICATE RAIN
SHOWERS AND DRIZZLE ARE FALLING PERIODICALLY ALONG MUCH OF OUR
COAST...AS FAR SOUTH AS YACHATS SO FAR...AND IN THE NORTHERN
WILLAMETTE VALLEY AND POINTS NORTHWARD. WETTING RAINS HAVE STARTED
MAKING AN APPEARANCE ALONG THE COAST AND IN THE SOUTH WASHINGTON
CASCADES WITH EVEN A FEW LOWER COLUMBIA RIVER VALLEY AND NORTHERN
WILLAMETTE VALLEY LOCATIONS STARTING TO PUSH A COUPLE TENTHS OF AN
INCH. THE RAINFALL WINNERS SO FAR ARE ELK ROCK RAWS AT 0.44 INCHES
AND 0.37 INCHES IN ARIEL IN THE SOUTH WASHINGTON CASCADE FOOTHILLS.
MODELS AGREE THE BAND OF SHOWERS STRETCHING NORTHEASTWARD ACROSS THE
AREA WILL SLOWLY SHIFT EASTWARD TODAY...BRINGING AT LEAST A FEW
SHOWERS TO THE REST OF THE WILLAMETTE VALLEY AND CENTRAL OREGON
CASCADES LATER THIS MORNING AND AFTERNOON. THE HRRR SUGGESTS SHOWER
COVERAGE SHOULD LESSON THIS AFTERNOON...AND THIS SEEMS CONSISTENT
WITH THE LARGER SCALE GLOBAL MODELS. SIGNIFICANT ADJUSTEMENTS TO POPS
AND QPF WERE MADE TO REFLECT REALITY THIS MORNING. EXPECT ADDITIONAL
UPDATES TODAY AS TRENDS EMERGE.
A TEMPORARY LULL IN PRECIPITATION SHOULD ARRIVE THIS EVENING AND
OVERNIGHT AS WEAK SURFACE RIDGING PUSHES NORTHEASTWARD INTO THE AREA.
HOWEVER...THE MAIN TROUGH AXIS AND COLD POOL ALOFT WILL PUSH ACROSS
THE AREA LATE SUNDAY. THIS SHOULD BRING ANOTHER ROUND OF SHOWERS TO
THE REGION WITH PERHAPS A THUNDERSTORM OR TWO DEPENDING ON CLOUD
COVER. WILL LIKELY BOOST POPS FURTHER WITH THE AFTERNOON FORECAST
PACKAGE FOR THIS TIME PERIOD. THE DRYING TREND AND RETURN TO HOT
WEATHER LOOKS ON TRACK FOR NEXT WEEK. /NEUMAN
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MUCH WARMER AND DRIER
PATTERN WILL DOMINATE THE EXTENDED PERIOD. STRONG HIGH PRES ALOFT
RETURNS TUE AND IS EXPECTED TO HOLD THROUGH MUCH OF THE WEEK. ECMWF
AND GFS SUGGEST A THERMALLY-INDUCED SURFACE TROUGH WILL FORM ALONG
THE COAST TUE NIGHT. THE THERMAL TROUGH COULD HOLD ALONG THE COAST
WED...ALLOWING SOME PART OF THE N OREGON COAST TO GET INTO THE 80S
TUE. MODELS DIFFER ON THE THERMAL TROUGH DETAILS...BUT SHOW IT
SOMEWHERE OVER THE INTERIOR VALLEYS WED AND POSSIBLY THU. 850 MB
FORECAST TEMPS CLIMB TO 22-24C...DEPENDING ON THE MODEL. SHOULD THIS
OCCUR...SOME INTERIOR LOWLAND LOCATIONS MAY SEE CLOSE TO 100 DEG.
THERE MAY BE SLIGHT RELIEF FRI AS A SHORT-WAVE MOVES ACROSS BRITISH
COLUMBIA...SUPRESSING THE 500 MB HEIGHTS JUST A BIT AND ALLOWING A
LITTLE MORE ONSHORE FLOW. ECMWF HINTS AT SOUTH FLOW ALOFT SPREADING
INTO S AND CENTRAL OREGON FRI...WITH THE AFOREMENTIONED SHORT-WAVE
ABOUT 12-24 HRS SLOWER THAN THE GFS. WEISHAAR
&&
.AVIATION...A WEAK FRONT CONTINUES TO PUSH INLAND ACROSS THE
REGION...PRESENTLY SITUATED JUST EAST OF A KDLS-KEUG-KOTH LINE AS
OF 15Z. PRIMARILY MVFR CIGS BEHIND THE FRONT AND THE HEAVIEST OF
RAIN PROVIDING FOR LOCAL IFR CONDITIONS. HOWEVER...SOME
IMPROVEMENT ALREADY ALONG THE NORTH COAST WHERE VFR CIGS HAVE
RETURNED. WITH ABUNDANT MOISTURE AND ONSHORE FLOW IN THE UNSTABLE
POST-FRONTAL AIR MASS...EXPECT SLIGHT IMPROVEMENT BUT CONTINUED LOWER
VFR TO HIGH MVFR CIGS ONCE THE MAIN FRONTAL BAND PASSES. SLOW
IMPROVEMENT THIS EVENING AND TONIGHT POSSIBLE...BUT ANOTHER WEAK
FRONT MOVES ACROSS THE REGION TOMORROW FOR A VERY SIMILAR OVERALL
PATTERN.
KPDX AND APPROACHES...MVFR CIGS WITH RAIN THIS MORNING WILL
CONTINUE TO SLIDE ACROSS THE AREA. MAY STILL SEE ONE MORE BAND OF
HEAVIER RAIN BEFORE 17Z THAT COULD BRING TEMPORARY IFR CIGS/VSBYS.
SLOW IMPROVEMENT THIS AFTERNOON AND EARLY TONIGHT BUT EXPECT
HIGHER MVFR TO LOWER VFR CIGS TO LINGER. ANOTHER WEAK FRONT
ARRIVES TOMORROW FOR VERY SIMILAR CONDITIONS.CULLEN
&&
.MARINE...A WEAK FRONT IS ADVANCING ONSHORE THIS MORNING...WITH
ANOTHER FRONT FOLLOWING CLOSELY BEHIND. THIS SECOND FRONT WILL
TRAVERSE THE WATERS LATE TONIGHT/EARLY SUNDAY. WINDS REMAIN BELOW
15 KT OVER THE WATERS THROUGH THE WEEKEND WITH FAIRLY WEAK SURFACE
PRESSURE GRADIENT. WINDS WILL SHIFT TO BECOME TONIGHT SOUTHERLY
AHEAD OF THE FRONT...BEFORE AGAIN BECOMING WEST-NORTHWEST BEHIND
THE FRONT ON SUNDAY. SEAS WILL BUILD TO NEAR 7 FT TONIGHT...BEFORE
EASING BY A FOOT OR TWO ON SUNDAY.
A MORE TYPICAL LATE JULY PATTERN RETURNS NEXT WEEK...AS THERMAL
TROUGH OVER NW CALIFORNIA AND SW OREGON WILL BUILD WHILE HIGH
PRES SITS OVER NE PAC. THIS WILL BRING RETURN OF GUSTY N TO NW
WINDS...ALONG WITH SHORT PERIOD CHOPPY WIND DRIVEN SEAS...ESPECIALLY
FROM CASCADE HEAD SOUTHWARD.CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1141 AM MDT SAT JUL 25 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 315 AM MDT SAT JUL 25 2015
WATER VAPOR IMAGERY SHOWED A STATIONARY UPPER RIDGE OVER THE
SOUTH CENTRAL CONUS WITH ACTIVE WESTERLY FLOW OVER THE NORTH
CENTRAL CONUS. SUBTROPICAL MOISTURE AND WEAK WAVES CIRCULATING
CLOCKWISE AROUND THE UPPER HIGH AIDED IN SEVERAL CLUSTERS OF
DEEP CONVECTION FROM THE CENTRAL PLAINS INTO THE LOWER/MID MS
VALLEY. A COMPLEX OF TSTORMS DEVELOPED ACROSS NORTHEAST WY
ASSOCIATED WITH THE LEFT FRONT QUADRANT OF UPPER JET STREAK.
THIS COMPLEX WILL CONTINUE TO TRACK EAST-NORTHEAST ACROSS
NORTHWEST SD OVERNIGHT. SURFACE ANALYSIS DEPICTED A WAVY FRONT
FROM A LOW IN NORTH CENTRAL IA ACROSS SOUTHERN NE...NORTHWEST KS
AND EAST CENTRAL CO THEN CURVING NORTHWEST INTO EASTERN WY. BACK
EDGE OF CIRRUS WAS MOVING THROUGH WESTERN NE LEAVING MOSTLY CLEAR
SKIES TO THE WEST.
THE LARGE SCALE PATTERN WE`VE BEEN ACCUSTOMED TO THE PAST SEVERAL
DAYS WILL CONTINUE WITH A CENTRAL CONUS RIDGE FLANKED BY TROUGHS
TO THE WEST AND EAST. ISOLATED CONVECTION DEVELOPED OVER THE
PLAINS LATE FRIDAY ALONG A INSTABILITY GRADIENT. THE GRADIENT
WILL SHIFT EAST OF THE CWA TODAY...HOWEVER JET ENERGY COMBINED
WITH LINGERING MID LEVEL MOISTURE MAY TRIGGER ISOLATED AFTERNOON
CONVECTION ACROSS THE HIGH PLAINS. THE MAJORITY OF THE MODELS
MAINTAIN DRY CONDITIONS...HOWEVER THE HRRR GENERATES A 20-30
PERCENT COVERAGE OF CONVECTION. NOT TOTALLY BUYING THE HRRR...WITH
10-15 PERCENT POPS FORECAST ATTM. 700MB TEMPERATURES PEAK NEAR 15C
TODAY WITH AFTERNOON HIGHS IN THE UPPER 80S-MID 90S FOR THE
PLAINS. IT WILL BE BREEZY WEST OF THE LARAMIE RANGE WITH SOUTHWEST
WINDS GUSTING TO NEAR 25 MPH.
HIGH TEMPERATURES SUNDAY AND MONDAY WILL BE 3-5 DEGREES WARMER
WITH 700MB TEMPERATURES PEAKING 16-17C. 90S WILL PREVAIL EAST
OF THE LARAMIE RANGE BOTH DAYS. MONDAY AFTERNOON WILL BE WARMEST
OF THE TWO DAYS...WITH A FEW LOCATIONS IN THE WESTERN NE PANHANDLE
TOPPING OUT AT 100 DEGREES. LOW LEVEL THERMAL/INSTABILITY AXIS
WILL RESIDE EAST OF THE CWA...HOWEVER WITH THE POSITION OF THE
RIGHT REAR QUADRANT OF THE UPPER JET OVERHEAD...CANNOT RULE OUT
A FEW AFTERNOON/EARLY EVENING TSTORMS FOR THE HIGH PLAINS SUNDAY
AND MONDAY. THE PRESSURE GRADIENT AND INCREASING SOUTHWEST FLOW
ALOFT AHEAD OF AN APPROACHING TROUGH AND COLD FRONT MONDAY WILL
INDUCE WINDY CONDITIONS WEST OF THE LARAMIE RANGE WITH GUSTS
POSSIBLY EXCEEDING 40 MPH.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 230 AM MDT SAT JUL 25 2015
WEATHER CONDITIONS WILL REMAIN ON THE DRIER SIDE THROUGH THE
LONGER TERM FORECAST PERIOD. MONDAY NIGHT STARTS OFF WITH AN
UPPER LEVEL TROUGH OVER THE NORTHERN ROCKIES. DEPENDING ON THE
EXACT TRACK OF THE UPPER LEVEL LOW COULD SEE A FEW THUNDERSTORMS
OVER FAR NORTHERN AND/OR EASTERN PORTIONS OF THE FORECAST AREA
MONDAY EVENING. CURRENTLY THE GFS AND ECMWF KEEP THE MAIN ENERGY
NORTH OF THE FORECAST AREA.
A REINFORCING PUSH OF COOLER AIR EXPECTED TUESDAY AS THE MAIN
UPPER LEVEL TROUGH PUSHES EAST INTO THE PLAINS. TIMING OF THE COOL
PUSH SHOULD KEEP CHANCES FOR PRECIPITATION AT A MINIMUM OVER THE
FORECAST AREA WITH THUNDERSTORM ACTIVITY LIKELY DEVELOPING WELL
EAST INTO CENTRAL NEBRASKA AND SOUTH INTO COLORADO. HIGH
TEMPERATURES TUESDAY SHOULD RANGE FROM THE LOWER 70S WEST TO
LOW-MID 80S INTO THE PLAINS.
MILD TEMPERATURES SHOULD CONTINUE WEDNESDAY WITH SOUTHEAST LOW
LEVEL FLOW IN PLACE OVER THE PLAINS. WEDNESDAY ALSO LOOKS TO BE ON
THE DRY SIDE WITH VERY MINIMAL CHANCES FOR PRECIPITATION...
ESPECIALLY WITH THE FORECAST AREA UNDER THE SUBSIDENCE SIDE OF THE
REAR UPPER LEVEL JET. ALSO LOOKING AT WESTERLY FLOW ALOFT
DEVELOPING WITH ZONAL FLOW IN PLACE OVER THE WESTERN CONUS.
WARMING TREND FOR LATTER PORTIONS OF NEXT WEEK WITH RIDGING OVER
THE WESTERN CONUS AND WEST TO NORTHWEST FLOW OVER THE FORECAST
AREA. HIGH TEMPERATURES SHOULD WARM INTO THE LOW 80S WEST TO
AROUND 90 INTO THE PLAINS THURSDAY AND SLIGHTLY WARMER FRIDAY.
EXPECTING VERY ISOLATED AFTERNOON THUNDERSTORMS ACTIVITY BUT
OVERALL CHANCES FOR WETTING RAIN WILL BE VERY LOW WITH
THUNDERSTORM COVERAGE LIKELY LESS THAN 10 PERCENT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1139 AM MDT SAT JUL 25 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD. WIDESPREAD
GUSTY WINDS WILL DEVELOP ALONG AND WEST OF THE LARAMIE RANGE BY
18Z SUN.
&&
.FIRE WEATHER...
ISSUED AT 222 AM MDT SAT JUL 25 2015
WARM AND MAINLY DRY CONDITIONS WILL CONTINUE FOR THE DISTRICTS
THROUGH MONDAY BEFORE THE PASSAGE OF A COLD FRONT TUESDAY. NEAR-
CRITICAL WINDS AND HUMIDITIES FOR PORTIONS OF EAST CENTRAL AND
SOUTH CENTRAL WYOMING CAN BE EXPECTED THIS WEEKEND. THE BEST
CHANCE FOR WIDESPREAD CRITICAL FIRE WEATHER CONDITIONS WILL BEGIN
MONDAY MORNING AS WINDS ALOFT INCREASE FOLLOWING POOR OVERNIGHT
HUMIDITY RECOVERIES. SOUTHWEST WINDS MAY GUST OVER 40 MPH WEST OF
THE LARAMIE RANGE MONDAY WITH AFTERNOON HUMIDITIES FALLING INTO
THE SINGLE DIGITS TO LOW TEENS PERCENT. COOLER TEMPERATURES AND
SLIGHTLY HIGHER HUMIDITIES WILL PREVAIL TUESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...MAJ
LONG TERM...SML
AVIATION...CLH
FIRE WEATHER...MAJ