Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/11/14
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
100 AM CDT WED JUL 9 2014
.AVIATION...09/06Z TAF CYCLE
CONVECTION ACRS CNTRL AND SRN AR WL CONT TO WEAKEN THRU THE EARLY
MRNG HRS...WITH MAINLY VFR/MVFR CONDS ANTICIPATED. ASSOCD FNTL
BNDRY IS PROGGED TO MEANDER ACRS THE SRN HALF OF THE FA LATER TODAY...
WITH VCTS MENTIONED AT KPBF AND KLLQ FOR THE AFTN HRS. EXPECT VFR
CONDS TO PREVAIL ACRS NRN AR AS DRIER AIR ADVECTS INTO THAT AREA
THRU THE PD. /44/
&&
.PREV DISCUSSION... /ISSUED 834 PM CDT TUE JUL 8 2014/
UPDATE...
QUICK UPDATE TO ADJUST POPS SIGNIFICANTLY FOR THE 00Z-06Z TIME
FRAME AS WIDESPREAD CONVECTION IS SITUATED ACROSS THE MIDDLE THIRD
OF THE STATE ROUGHLY. SVR TSTORM WATCH 406 IS IN EFFECT FOR
SEVERAL COUNTIES ACROSS THE FA THROUGH 11 PM LOCAL TIME.
PREV DISCUSSION... /ISSUED 234 PM CDT TUE JUL 8 2014/
SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
SHOWER AND THUNDERSTORM ACTIVITY OCCURRED ACROSS THE NORTH EARLIER
TODAY AS A DECAYING MCS MOVED THROUGH CENTRAL MISSOURI. OTHER THAN A
STRAY SHOWER OR TWO THIS AFTERNOON...ALL PRECIPITATION FROM THIS
FEATURE IS PRETTY MUCH SAID AND DONE. ATTENTION WILL TURN BACK A
WEAK COLD FRONT THAT IS ROUGHLY LOCATED FROM NORTHEAST OKLAHOMA
THROUGH CENTRAL MISSOURI AND EXTENDING BACK INTO THE OHIO VALLEY.
MODELS REMAIN GENERALLY CONSISTENT IN THEIR HANDLING OF A LONG WAVE
TROUGH...CLEARLY VISIBLE ON MOISTURE CHANNEL IMAGERY OVER SOUTHERN
QUEBEC AT THIS TIME. A SERIES OF UPPER LEVEL IMPULSES WILL HELP TO
MOVE THE AFOREMENTIONED FRONT INTO THE STATE. THE HRRR ONCE AGAIN
DID A GOOD JOB IN THE VERY NEAR TERM AND ONCE AGAIN THE ECMWF HAS
BEEN SLIGHTLY MORE CONSISTENT VERSUS OTHER SHORT TERM MODELS AND THE
FORECAST WILL BE TRENDED THIS WAY.
AFOREMENTIONED BOUNDARY IS EXPECTED TO DROP INTO THE NORTHERN PART
OF THE STATE THIS EVENING AND SAG TO THE SOUTH...REACHING CENTRAL
SECTIONS BY MORNING. THERE ARE SOME DIFFERENCES BETWEEN THE MODELS
ON WHERE THIS FRONT EVENTUALLY ENDS UP BUT CURRENT THINKING IS IT
WILL REACH THE LOUISIANA BORDER LATE WEDNESDAY. AFTER STALLING
BRIEFLY THE BOUNDARY WILL LIFT BACK TO THE NORTH AS A WARM FRONT AS
RIDGING BEGINS TO GETS REESTABLISHED OVER THE SOUTHERN HIGH PLAINS.
PRECIPITATION WILL ACCOMPANY THE BOUNDARY AS IT ADVANCES THROUGH AND
THEN BACK OUT OF THE STATE. A WIDESPREAD HEAVY RAIN EVENT IS NOT
EXPECTED IN SPITE OF PWATS IN EXCESS OF 1.75 INCHES POOLING ALONG
THE BOUNDARY. STILL WITH THIS MUCH MOISTURE IN PLACE...LOCALIZED
AMOUNTS IN EXCESS OF AN INCH CAN NEVER BE RULED OUT. TEMPERATURES
CONTINUE TO RUN BELOW GUIDANCE AND WITH EXPECTED RAIN AND CLOUD
COVER OVER THE NEXT FEW DAYS...WOULD EXPECT THIS CONTINUE. AS
SUCH...GUIDANCE WILL BE UNDERCUT A FEW DEGREES.
LONG TERM...SATURDAY THROUGH TUESDAY...
THE INFLUENCE OF THE UPPER RIDGE WILL BEGIN LESSENING OVER THE
WEEKEND ACROSS THE NATURAL STATE AS UPPER FLOW TRANSITIONS TO A MORE
NWRLY FLOW OVER THE REGION. BEFORE THIS HAPPENS HOWEVER...TEMPS ON
SAT WILL REMAIN WELL INTO THE MID AND UPPER 90S...WITH HEAT INDEX
VALUES OVER 100 IN MANY SPOTS. EXPECT PRECIP CHANCES TO REMAIN
LOW...WITH MAYBE SOME ISOLATED AFTERNOON CONVECTION ON SAT. SUN WILL
ALSO REMAIN WARM...BUT COULD SEE A COUPLE DEGREES COOLER ACROSS THE
AREA AS HEIGHTS ALOFT BEGIN TO FALL SOME. KEEP FORECAST DRY FOR SUN
AS WELL...THOUGH THERE COULD ALSO BE SOME ISOLATED AFTERNOON
CONVECTION. BETTER RAIN CHANCES WILL COME EARLY NEXT WEEK AS A COLD
FRONT APPROACHES FROM THE NORTH. ALSO HAVE TEMPS COOLING WITH
INCREASED PRECIP CHANCES...AND EVEN FROM NRLY FLOW BEHIND THE FRONT
AT THE END OF THE FORECAST IF THE FRONT PUSHES FAR ENOUGH SOUTH BY
THAT TIME.
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
319 PM MDT WED JUL 9 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 319 PM MDT WED JUL 9 2014
ANOTHER ROUND OF TSRA OVER THE AREA TODAY...THOUGH SO FAR STORMS
HAVE BEEN WEAKER AND HIGHER BASED THAN YESTERDAY`S ACTIVITY...AS
PRECIPITABLE WATER HAS DECREASED SIGNIFICANTLY AND LOW LEVEL
MOISTURE HAS MIXED AT SOME LOCATIONS ALONG THE I-25 CORRIDOR. STILL
SOME FAIRLY STRONG INSTABILITY LEFT NEAR THE KS BORDER...WHERE
DEWPOINTS HAVE STAYED IN THE 50S...LEADING TO CAPES IN THE 1-2K J/KG
RANGE. FOR THE REST OF THE AFTERNOON AND EARLY EVENING...EXPECT SCT
TSRA TO CONTINUE OVER THE MTS...WITH A FEW STORMS DRIFTING ACROSS
THE VALLEYS AND INTERSTATE 25 CORRIDOR. LAST COUPLE RUNS OF THE HRRR
SUGGEST STORM INTENSITY WON`T BE PARTICULARLY STRONG...ESPECIALLY AS
STORMS MOVE AWAY FROM THE HIGHER TERRAIN. STILL...COULD BE A FEW
SMALL POCKETS OF BRIEF HEAVY RAIN...MAINLY NEAR THE NM BORDER WHERE
INSTABILITY IS A LITTLE BETTER. OVER THE FAR EASTERN PLAINS...WILL
HAVE TO WATCH FOR POTENTIAL STRONG/SEVERE CONVECTION DEVELOPING OVER
NERN CO BUILDING SOUTHWARD DURING THE EVENING...AS FAIRLY STRONG
SHEAR AND HEALTHY SURFACE S-SE FLOW MAY KEEP STORMS GOING PAST
SUNSET. HRRR SUPPORTS THIS IDEA WITH A FEW CELLS MOVING ACROSS
KIOWA/PROWERS COUNTIES 03Z-04Z. OVERNIGHT...MOST ACTIVITY WILL DIE
DURING THE EVENING...THOUGH WILL KEEP SOME LOW POPS GOING OVER THE
SAN JUANS WHERE MODELS SUGGEST DEEPER MOISTURE AND A FEW SHOWERS MAY
LINGER PAST MIDNIGHT.
ON THURSDAY...LITTLE CHANGE IN THE AIR MASS FROM TODAY...THOUGH WITH
SURFACE TROUGH PUSHING SLIGHTLY EAST TOWARD THE KS BORDER SUSPECT A
LITTLE BETTER MIXING WILL OCCUR ALONG AND EAST OF THE
MOUNTAINS...LEADING TO WEAKER/FEWER STORMS ON THE PLAINS/I-25
CORRIDOR. MOUNTAIN ACTIVITY LOOKS LITTLE CHANGED...WITH DEEPEST
MOISTURE ALONG THE CONTINENTAL DIVIDE ONCE AGAIN. MAX TEMPS WILL
LIKELY CREEP UP A FEW DEGREES OVER EASTERN SECTIONS WITH BETTER
MIXING...WITH READINGS NEAR OR A LITTLE OVER 100F FROM PUEBLO
EASTWARD.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM MDT WED JUL 9 2014
THE WEATHER PATTERN IS EXPECTED TO CHANGE VERY LITTLE AS A RIDGE OF
HIGH PRESSURE REMAINS OVER THE AREA THROUGH THE WEEKEND. MONSOON
MOISTURE TRAPPED UNDER THE RIDGE WILL PROVIDE THE FUEL FOR A DAILY
SHOT OF SHOWERS AND THUNDERSTORMS. CONVECTION WILL BE MAINLY
DIURNAL...BUT MAY START A BIT EARLIER OVER THE HIGHER TERRAIN DURING
THE LATE MORNING HRS...AS WELL AS LINGER INTO THE OVERNIGHT.
CONVECTION IS FORECAST TO BE SCATTERED OVER THE MTS...LIKELY OVER
THE PEAKS...AND MORE ISOLATED IN NATURE ACROSS THE PLAINS AND SAN
LUIS VALLEY.
THURSDAY NIGHT THROUGH SUNDAY...A SHORTWAVE PASSING TO THE NORTH
LATE THU WILL PUSH A COLD FRONT DOWN INTO EASTERN CO EARLY
FRI...THEN A REINFORCING BLAST OF COOLER MORE MOIST AIR COMES IN ON
SAT. THIS MEANS VERY WARM TEMPS FOR THE FORECAST AREA ON FRI...NEAR
NORMAL LEVELS ON SAT...THEN COOLER ON SUN. THIS WILL ALSO RESULT IN
SLIGHTLY HIGHER PCPN CHANCES FOR THE E PLAINS...ESPECIALLY ALONG THE
I25 CORRIDOR...FOR SAT AND SUN.
MONDAY THROUGH WEDNESDAY...LONG RANGE MODELS INTRODUCE A LARGE UPPER
LEVEL LOW PRESSURE SYSTEM THAT DROPS OUT OF CANADA AND HEADS TOWARDS
THE GREAT LAKES REGION ON MON...THEN SWEEPS IT TOWARDS THE NEW
ENGLAND STATES BY MIDWEEK. IF THIS OCCURS...IT MIGHT PUSH THE UPPER
RIDGE OVER THE ROCKIES MORE TO THE SW. FOR NOW...EXPECTED DAY TO DAY
CONVECTION CHANCES DO NOT SEEM TO CHANGE MUCH...SAVE FOR COOLER
TEMPS ON WED. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 319 PM MDT WED JUL 9 2014
SCT TSRA OVER THE MOUNTAINS WILL PERSIST INTO THE EARLY EVENING...WITH
STORMS DRIFTING ACROSS LOWER ELEVATIONS...INCLUDING ALL TAF SITES
21-02Z. IN GENERAL...WITH LESS MOISTURE TODAY TSRA SHOULD BE WEAK
AND HIGHER BASED AND ONLY VERY BRIEF MVFR CONDITIONS ARE EXPECTED
UNDER THE STRONGER STORMS. HAVE INCLUDED VCTS IN ALL TAFS FROM
20Z-02Z...THEN VFR CONDITIONS MOST LOCATIONS OVERNIGHT THROUGH THU
MORNING. VERY SIMILAR CONDITIONS AGAIN ON THURSDAY...WITH TSRA
OVER THE MOUNTAINS DRIFTING TOWARD TAF SITES AFTER 20Z.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS ALBANY NY
446 PM EDT WED JUL 9 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND
WESTERN NEW ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN
TOMORROW FROM THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER.
THE SURFACE HIGH WILL CONTINUE TO BRING COMFORTABLE HUMIDITY LEVELS
THURSDAY NIGHT INTO FRIDAY WITH SEASONABLE TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 442 PM EDT...A SEVERE THUNDERSTORM WATCH HAS BEEN POSTED
FROM SCHOHARIE...ALBANY...AND RENSSELAER COUNTIES IN NY
SOUTH...AND ACROSS ALL OF WRN NEW ENGLAND UNTIL 10 PM.
THE MAIN THREAT WILL BE DAMAGING WINDS...ALTHOUGH ISOLATED LARGE
HAIL WILL BE POSSIBLE. THE LIMITING FACTORS FOR LARGE HAIL ARE
WEAK MID LEVEL LAPSE RATES GENERALLY LESS THAN 6C/KM...AND ROBUST
INSTABILITY WITH MLCAPES GENERALLY 500-750 J/KG...AND SBCAPES OF
500-1000 J/KG...EXCEPT 1000-1500 J/KG SOUTH OF THE CAPITAL
REGION...BASED ON THE LATEST SPC MESOANALYSIS RAP DATA. THE BETTER
INSTABILITY IS SOUTH OF THE CAPITAL REGION WHERE SFC DEWPTS HAVE
RISEN INTO THE 60-65F RANGE. THE 0-6 KM EFFECTIVE BULK SHEAR IS
35-40 KTS AND THE SOUNDINGS ARE UNIDIRECTIONAL ABOVE THE BOUNDARY
LAYER TO 300 HPA. SOME CONVECTIVE LINES ARE POSSIBLE WITH BOWING
SEGMENTS FOR DAMAGING WINDS 50 KTS AND GREATER. THIS CONVECTION
FIRED A LITTLE FARTHER NORTH THAN EARLIER THINKING BUT SEEMS TO BE
FIRING WHERE THE BETTER INSTABILITY IS IN PLACE /1000-1500 J/KG/.
MULTI-CELLULAR CLUSTERS WILL LIKELY FORM INTO LINES WITH DAMAGING
WIND THREAT.
THE FRONT MOVES THROUGH EARLY THIS EVENING WITH THE SHOWERS AND
THUNDERSTORMS ENDING FROM THE CAPITAL REGION SOUTH AND EAST. THE
LATEST HIRES WRF AND HRRR LAYER COMP REF PRODUCT SHOWS THE SHOWERS
AND TSTORMS ENDING BTWN 00Z-03Z WITH CLEARING CONDITIONS IN THE
WAKE OF THE FRONTAL PASSAGE.
SOME PATCHY FOG IS POSSIBLE IN THE HUDSON RIVER VALLEY...SRN
DACKS...AND WRN NEW ENGLAND /ESPECIALLY NEAR THE CT RIVER
VALLEY/...AND JUST WEST OF THE SRN GREENS AND BERKSHIRES. THE
WINDS STAYING UP OVER THE IMMEDIATE CAPITAL DISTRICT MAY PREVENT
PATCHY FOG FORMATION.
SOME WEAK COLD ADVECTION WILL OCCUR IN THE WAKE OF THE FRONT. LOWS
WILL BE IN THE U50S TO L60S FROM THE CAPITAL REGION SOUTH AND
EAST. EXPECT MAINLY 50-55F READINGS NORTH AND WEST...WITH SOME
U40S OVER THE SRN DECKS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
TOMORROW...AT THE SFC...HIGH PRESSURE WILL GRADUALLY BE BUILDING
INTO THE NORTHEAST FROM THE GREAT LAKES REGION. THE LONGWAVE H500
POSITIVELY TILTED TROUGH AXIS REMAINS UPSTREAM ACCORDING TO THE
GFS/ECMWF/NAM. SOME SHORT-WAVE ENERGY ROUNDING THE BASE OF THE
TROUGH COUPLED WITH THE FRONTAL BOUNDARY HUNG UP NEAR SE PA/NJ AND
THE DELMARVA REGION MAY ALLOW A WEAK WAVE TO MOVE ALONG IT. THIS
DISTURBANCE DOES NOT APPEAR IT WILL BE FAR ENOUGH TO NORTH TO
IMPACT THE AREA...EXCEPT FOR SOME CLOUDS. THE SUBSIDENCE FROM THE
SFC HIGH BUILDING IN SHOULD PROMOTE PARTLY TO MOSTLY SUNNY
CONDITIONS WITH HIGHS IN THE U70S TO L80S IN THE VALLEYS...AND
U60S TO M70S OVER THE MTNS.
THURSDAY NIGHT...HIGH PRESSURE BUILDS OVER THE REGION WITH CLEAR
SKIES AND LIGHT TO CALM WINDS. SOME RADIATIONAL COOLING WILL ALLOW
TEMPS TO FALL INTO THE 50S WITH COMFORTABLE HUMIDITY LEVELS. SOME
MID AND U40S WILL BE POSSIBLE OVER THE SRN DACKS REGION.
FRI-FRI NIGHT...HIGH PRESSURE MOVES OVER NY AND NEW ENGLAND WITH A
CONTINUED STRETCH OF FAIR AND DRY WEATHER. SFC DEWPTS WILL BE
MAINLY IN THE 50S. HUMIDITY LEVELS WILL BE VERY COMFORTABLE. H850
TEMPS WILL BE IN THE 12C TO 14C RANGE WITH SEASONABLE HIGH TEMPS
IN THE U70S TO M80S IN THE VALLEYS...AND GENERALLY 70S OVER THE
MTNS. LOWS WILL GENERALLY BE IN THE 50S TO L60S WITH SOME HIGH
CLOUDS INCREASING FROM THE SOUTH AND WEST AHEAD OF A WEAK WARM
FRONT....AS THE SFC HIGH DRIFTS OFFSHORE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE FIRST HALF OF THE WEEKEND DURING THE DAY ON SATURDAY WILL
FEATURE TRANQUIL WEATHER AS A ZONAL UPPER LEVEL FLOW AND A WEAK
SURFACE HIGH PRESSURE WILL BE IN PLACE WITH HIGH TEMPERATURES
RANGING FROM THE UPPER 70S TO MID 80S.
AS WE GO FROM SUNDAY NIGHT THROUGH THE REST OF THE EXTENDED
PERIOD...WE WILL BE IN ACTIVE PATTERN AS A SERIES OF UPPER LEVEL
IMPULSES RIDING AROUND THE BASE OF AN UPPER LEVEL LOW WILL BE MOVING
THROUGH THE REGION AS THE MAIN UPPER LEVEL FEATURES SLOWLY MOVES
EAST ACROSS SOUTHERN ONTARIO NORTHEASTWARD INTO QUEBEC. A SERIES OF
BOUNDARIES AND A COLD FRONT WILL MAKES ITS WAY THROUGH THE REGION AS
WE GO THROUGH THE DAY ON TUESDAY WITH A SURFACE LOW THAT WILL
DEVELOP IN SOUTHERN CANADA. T850 WILL BE BETWEEN 8C AND 11C FROM THE
LATEST 12Z MODELS AND NUMERICAL GUIDANCE AND WITH T500 COLDER THAN
-10C IN CONJUNCTION WITH DAYTIME HEATING...SHOWERS AND THUNDERSTORMS
ARE POSSIBLE AS WE GO THROUGH EARLY NEXT WEEK. WITH TEMPERATURES
THAT COLD ALOFT...SOME THUNDERSTORMS MAY BE CAPABLE OF PRODUCING
SOME GUSTY WINDS AND HAILSTONES. WINDS WILL BE OUT OF THE SOUTHWEST
THROUGHOUT THE EXTENDED PERIOD TO MORE OF A WESTERLY FLOW AS WE GO
PAST TUESDAY AFTER A FRONTAL SYSTEM PASSES THROUGH. HIGH
TEMPERATURES ON SUNDAY THROUGH TUESDAY WILL RANGE FROM THE MID 70S
TO LOWER 80S. TEMPERATURES AFTER THE FRONTAL PASSAGE FRO THE DAY ON
WEDNESDAY WILL RANGE FROM THE UPPER 60S TO NEAR 70 IN THE
ADIRONDACKS TO UPPER 70S IN MID HUDSON VALLEY.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD ENDING AT
18Z THURSDAY. THE EXCEPTIONS WILL BE POSSIBLE CONVECTION THIS
AFTERNOON AND EVENING WHICH COULD PRODUCE BRIEF PERIODS OF MVFR TO
IFR CONDITIONS AT THE TAF SITES. THE REGION IS ALSO IN A SLIGHT RISK
FOR SEVERE TSTMS...SO THERE IS THE POTENTIAL FOR LARGE HAIL AND
STRONG WINDS...BUT DUE TO THE ISOLD TO SCT NATURE OF THE CONVECTION
THIS AFTN/EVE...WILL ONLY FORECAST A TEMPO GROUP FOR TSTMS BETWEEN
18Z AND 22Z WITH MVFR CONDITIONS. ANY CONVECTION WILL END BETWEEN
00Z AND 02Z THIS EVENING.
LATER TONIGHT MVFR/POSSIBLY IFR FOG POSSIBLE...ESPECIALLY WHERE PCPN
OCCURS THIS AFTN/EVE. THE MOST LIKELY AREA FOR MVFR/IFR FOG WILL BE
KGFL.
SURFACE WINDS WILL BE SOUTH TO SOUTHWEST MOST OF THE AFTN AT 8 TO 12
KTS WITH GUSTS OF 15 TO 20 KTS. THE WINDS WILL TEND TO BECOME MORE
WESTERLY TOWARD SUNSET WITH THE SPEEDS DECREASING. GENERALLY LIGHT
AND VARIABLE WINDS LATE TONIGHT AND EARLY THURSDAY MORNING...THEN
NORTH OR NORTHWEST AT 8 KTS OR LESS ON WEDNESDAY.
OUTLOOK...
THURSDAY TO SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. ISOLATED SHRA.
SUNDAY TO MONDAY : MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
&&
.FIRE WEATHER...
A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND WESTERN NEW
ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN TOMORROW FROM
THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER...THAT WILL LAST
INTO FRIDAY.
THE RH VALUES WILL HAVE AN EXCELLENT RECOVERY TO 85 TO 100 PERCENT
TONIGHT...THEN LOWER TO 35 TO 50 PERCENT TOMORROW AFTERNOON.
ANOTHER NEAR FULL RECOVERY IS LIKELY FRIDAY MORNING WITH DEW
FORMATION WITH THE RH VALUES INCREASING TO 85 TO 100 PERCENT.
THE WINDS WILL SHIFT FROM THE SOUTH TO SOUTHWEST EARLY THIS
EVENING TO THE WEST TO NORTHWEST AT 5 TO 15 MPH. THE WINDS WILL BE
FROM THE NORTH TO NORTHWEST AT 5 TO 10 MPH ON THURSDAY...AND
BECOME LIGHT AND VARIABLE IN DIRECTION AT 5 MPH OR LESS THURSDAY NIGHT.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS
ACROSS THE HYDRO SERVICE AREA.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING
RAINFALL AMOUNTS OF ONE TENTH...TO ONE THIRD OF AN INCH EARLY THIS
EVENING WITH LOCALL HIGHER AMOUNTS.
GENERALLY DRY CONDITIONS ARE EXPECTED FROM TONIGHT THROUGH AT
LEAST EARLY SATURDAY. ANOTHER DISTURBANCE WILL BRING SOME
SCATTERED SHOWERS AND THUNDERSTORMS FOR THE 2ND HALF OF THE
WEEKEND INTO MONDAY WITH RAINFALL AMOUNTS IN THE TENTH TO HALF
AN INCH RANGE WITH LOCALLY HIGHER AMOUNTS.
SOME VERY MINOR RISES ON AREA RIVERS OR STREAMS COULD OCCUR FROM
THE RECENT RAINFALL...OTHERWISE MAIN STEM RIVER LEVELS ARE
EXPECTED TO REMAIN STEADY...OR FALL SLIGHTLY THROUGH SATURDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...LFM
AVIATION...GJM
FIRE WEATHER...KL/WASULA
HYDROLOGY...KL/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
404 PM EDT WED JUL 9 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND
WESTERN NEW ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN
TOMORROW FROM THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER.
THE SURFACE HIGH WILL CONTINUE TO BRING COMFORTABLE HUMIDITY LEVELS
THURSDAY NIGHT INTO FRIDAY WITH SEASONABLE TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 402 PM EDT...DESPITE THE SLIGHT RISK IN PLACE THIS
AFTERNOON...THE SHOWERS AND THUNDERSTORMS THAT HAVE DEVELOPED SO
FAR HAVE REMAINED MAINLY BELOW SEVERE LIMITS. THE LIMITING
FACTORS ARE WEAK MID LEVEL LAPSE RATES GENERALLY LESS THAN
6C/KM...AND ROBUST INSTABILITY WITH MLCAPES GENERALLY 500-750
J/KG...AND SBCAPES OF 500-1000 J/KG...EXCEPT 1000-1500 J/KG SOUTH
OF THE CAPITAL REGION...BASED ON THE LATEST SPC MESOANALYSIS RAP
DATA. THE BETTER INSTABILITY IS SOUTH OF THE CAPITAL REGION WHERE
SFC DEWPTS HAVE RISEN INTO THE 60-65F RANGE. THE 0-6 KM EFFECTIVE
BULK SHEAR IS 35-40 KTS AND THE SOUNDINGS ARE UNIDIRECTIONAL ABOVE
THE BOUNDARY LAYER TO 300 HPA. SOME CONVECTIVE LINES ARE
POSSIBLE...AND THE QUESTION WILL BE WHERE ANY STRONGER WINDS MIX
TO THE SFC WITH ANY THUNDERSTORM. THE BEST CHANCE FOR SOME STRONG
TO POSSIBLY SEVERE THUNDERSTORMS EARLY THIS EVENING IS OVER THE
SOUTHEAST CATSKILLS...MID HUDSON VALLEY...AND BERKS SOUTH...MAINLY
SOUTH OF THE CAPITAL REGION.
THE FRONT MOVES THROUGH EARLY THIS EVENING WITH THE SHOWERS AND
THUNDERSTORMS ENDING FROM THE CAPITAL REGION SOUTH AND EAST. THE
LATEST HIRES WRF AND HRRR LAYER COMP REF PRODUCT SHOWS THE SHOWERS
AND TSTORMS ENDING BTWN 00Z-03Z WITH CLEARING CONDITIONS IN THE
WAKE OF THE FRONTAL PASSAGE.
SOME PATCHY FOG IS POSSIBLE IN THE HUDSON RIVER VALLEY...SRN
DACKS...AND WRN NEW ENGLAND /ESPECIALLY NEAR THE CT RIVER
VALLEY/...AND JUST WEST OF THE SRN GREENS AND BERKSHIRES. THE
WINDS STAYING UP OVER THE IMMEDIATE CAPITAL DISTRICT MAY PREVENT
PATCHY FOG FORMATION.
SOME WEAK COLD ADVECTION WILL OCCUR IN THE WAKE OF THE FRONT. LOWS
WILL BE IN THE U50S TO L60S FROM THE CAPITAL REGION SOUTH AND
EAST. EXPECT MAINLY 50-55F READINGS NORTH AND WEST...WITH SOME
U40S OVER THE SRN DECKS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
TOMORROW...AT THE SFC...HIGH PRESSURE WILL GRADUALLY BE BUILDING
INTO THE NORTHEAST FROM THE GREAT LAKES REGION. THE LONGWAVE H500
POSITIVELY TILTED TROUGH AXIS REMAINS UPSTREAM ACCORDING TO THE
GFS/ECMWF/NAM. SOME SHORT-WAVE ENERGY ROUNDING THE BASE OF THE
TROUGH COUPLED WITH THE FRONTAL BOUNDARY HUNG UP NEAR SE PA/NJ AND
THE DELMARVA REGION MAY ALLOW A WEAK WAVE TO MOVE ALONG IT. THIS
DISTURBANCE DOES NOT APPEAR IT WILL BE FAR ENOUGH TO NORTH TO
IMPACT THE AREA...EXCEPT FOR SOME CLOUDS. THE SUBSIDENCE FROM THE
SFC HIGH BUILDING IN SHOULD PROMOTE PARTLY TO MOSTLY SUNNY
CONDITIONS WITH HIGHS IN THE U70S TO L80S IN THE VALLEYS...AND
U60S TO M70S OVER THE MTNS.
THURSDAY NIGHT...HIGH PRESSURE BUILDS OVER THE REGION WITH CLEAR
SKIES AND LIGHT TO CALM WINDS. SOME RADIATIONAL COOLING WILL ALLOW
TEMPS TO FALL INTO THE 50S WITH COMFORTABLE HUMIDITY LEVELS. SOME
MID AND U40S WILL BE POSSIBLE OVER THE SRN DACKS REGION.
FRI-FRI NIGHT...HIGH PRESSURE MOVES OVER NY AND NEW ENGLAND WITH A
CONTINUED STRETCH OF FAIR AND DRY WEATHER. SFC DEWPTS WILL BE
MAINLY IN THE 50S. HUMIDITY LEVELS WILL BE VERY COMFORTABLE. H850
TEMPS WILL BE IN THE 12C TO 14C RANGE WITH SEASONABLE HIGH TEMPS
IN THE U70S TO M80S IN THE VALLEYS...AND GENERALLY 70S OVER THE
MTNS. LOWS WILL GENERALLY BE IN THE 50S TO L60S WITH SOME HIGH
CLOUDS INCREASING FROM THE SOUTH AND WEST AHEAD OF A WEAK WARM
FRONT....AS THE SFC HIGH DRIFTS OFFSHORE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
WE BEGIN THE LONG TERM WITH A TRANQUIL START TO THE WEATHER ON
SATURDAY MORNING WITH SURFACE RIDGE OVER THE REGION.
HOWEVER...UPSTREAM WARM FRONT WILL BE APPROACHING THROUGHOUT THE
DAY. NCEP MODEL AND INTERNATIONAL GLOBAL MODEL SUITES DIFFER WITH
TIMING OF THIS FEATURE AS WPC GUIDANCE OFFERS A MORE STABLE
SOLUTION. THE FORECAST WILL FAVOR A DRIER FORECAST AND NEAR
SEASONABLE TEMPERATURES.
THE REMAINDER OF THE FORECAST BECOMES INCREASINGLY MORE ACTIVE AS AN
UNSEASONABLY DEEP UPPER LOW BEGINS TO DIVE SOUTHWARD ACROSS CENTRAL
CANADA. SOUTHERN PERIPHERY OF THIS DIGGING TROUGH WILL EXPERIENCE
AN INCREASE IN WIND MAGNITUDES. THE COMBINATION OF THESE INCREASING
UPPER DYNAMICS...SURFACE CONVERGENCE ALONG COLD FRONTS...AND LIKELY
INSTABILITY TO RESULT IN THE CHANCE FOR CONVECTION BEGINNING SUNDAY
AND CONTINUING THROUGH TUESDAY. WE WILL KEEP POPS WELL INTO THE
SCATTERED CATEGORY.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD ENDING AT
18Z THURSDAY. THE EXCEPTIONS WILL BE POSSIBLE CONVECTION THIS
AFTERNOON AND EVENING WHICH COULD PRODUCE BRIEF PERIODS OF MVFR TO
IFR CONDITIONS AT THE TAF SITES. THE REGION IS ALSO IN A SLIGHT RISK
FOR SEVERE TSTMS...SO THERE IS THE POTENTIAL FOR LARGE HAIL AND
STRONG WINDS...BUT DUE TO THE ISOLD TO SCT NATURE OF THE CONVECTION
THIS AFTN/EVE...WILL ONLY FORECAST A TEMPO GROUP FOR TSTMS BETWEEN
18Z AND 22Z WITH MVFR CONDITIONS. ANY CONVECTION WILL END BETWEEN
00Z AND 02Z THIS EVENING.
LATER TONIGHT MVFR/POSSIBLY IFR FOG POSSIBLE...ESPECIALLY WHERE PCPN
OCCURS THIS AFTN/EVE. THE MOST LIKELY AREA FOR MVFR/IFR FOG WILL BE
KGFL.
SURFACE WINDS WILL BE SOUTH TO SOUTHWEST MOST OF THE AFTN AT 8 TO 12
KTS WITH GUSTS OF 15 TO 20 KTS. THE WINDS WILL TEND TO BECOME MORE
WESTERLY TOWARD SUNSET WITH THE SPEEDS DECREASING. GENERALLY LIGHT
AND VARIABLE WINDS LATE TONIGHT AND EARLY THURSDAY MORNING...THEN
NORTH OR NORTHWEST AT 8 KTS OR LESS ON WEDNESDAY.
OUTLOOK...
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
A COLD FRONT WILL MOVE ACROSS EASTERN NEW YORK AND WESTERN NEW
ENGLAND EARLY THIS EVENING WITH ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS ENDING. HIGH PRESSURE WILL BUILD IN TOMORROW FROM
THE GREAT LAKES REGION WITH FAIR AND DRIER WEATHER...THAT WILL LAST
INTO FRIDAY.
THE RH VALUES WILL HAVE AN EXCELLENT RECOVERY TO 85 TO 100 PERCENT
TONIGHT...THEN LOWER TO 35 TO 50 PERCENT TOMORROW AFTERNOON.
ANOTHER NEAR FULL RECOVERY IS LIKELY FRIDAY MORNING WITH DEW
FORMATION WITH THE RH VALUES INCREASING TO 85 TO 100 PERCENT.
THE WINDS WILL SHIFT FROM THE SOUTH TO SOUTHWEST EARLY THIS
EVENING TO THE WEST TO NORTHWEST AT 5 TO 15 MPH. THE WINDS WILL BE
FROM THE NORTH TO NORTHWEST AT 5 TO 10 MPH ON THURSDAY...AND
BECOME LIGHT AND VARIABLE IN DIRECTION AT 5 MPH OR LESS THURSDAY NIGHT.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE ANTICIPATED THE NEXT 5 DAYS
ACROSS THE HYDRO SERVICE AREA.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BRING
RAINFALL AMOUNTS OF ONE TENTH...TO ONE THIRD OF AN INCH EARLY THIS
EVENING WITH LOCALL HIGHER AMOUNTS.
GENERALLY DRY CONDITIONS ARE EXPECTED FROM TONIGHT THROUGH AT
LEAST EARLY SATURDAY. ANOTHER DISTURBANCE WILL BRING SOME
SCATTERED SHOWERS AND THUNDERSTORMS FOR THE 2ND HALF OF THE
WEEKEND INTO MONDAY WITH RAINFALL AMOUNTS IN THE TENTH TO HALF
AN INCH RANGE WITH LOCALLY HIGHER AMOUNTS.
SOME VERY MINOR RISES ON AREA RIVERS OR STREAMS COULD OCCUR FROM
THE RECENT RAINFALL...OTHERWISE MAIN STEM RIVER LEVELS ARE
EXPECTED TO REMAIN STEADY...OR FALL SLIGHTLY THROUGH SATURDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...BGM
AVIATION...GJM
FIRE WEATHER...KL/WASULA
HYDROLOGY...KL/WASULA
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1039 AM EDT WED JUL 9 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH TODAY...THEN STALL NEARBY THROUGH
THURSDAY. HIGH PRESSURE WILL BUILD IN FOR THE WEEKEND. A FRONTAL
SYSTEM WILL ARRIVE EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AREA WILL REMAIN ON THE EASTERN SIDE OF AN UPPER LEVEL LONGWAVE
TROUGH TODAY INTO THURSDAY WITH A COLD FRONT APPROACHING FROM THE
WEST. TROUGH AXIS REMAINS NEAR THE GREAT LAKES REGION. AT THE
SURFACE...COLD FRONT APPROACHES FROM THE WEST. WITH LOW LEVEL
CONVERGENCE ALONG THE FRONT...AND CAPE VALUES OF 1000-1500
J/KG...MAINLY AWAY FROM THE COAST...ISOLATED SHOWERS AND
THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON. 12Z HRRR RUN HINTS AT
DEVELOPMENT AFTR 18Z...WITH THE BEST CHC LATE AFTN INTO THE
EVENING OVER INTERIOR PORTIONS OF THE AREA.
TEMPERATURES WILL BE SLIGHTLY COOLER THAN YESTERDAY...BUT STILL
ABOVE NORMAL...MIDDLE 80S TO LOWER 90S. HUMIDITY LEVELS COME DOWN
AS DEWPOINTS WILL DROP TO THE LOWER TO MIDDLE 60S FOR THE MOST PART.
THERE IS A HIGH RISK FOR RIP CURRENT DEVELOPMENT ON ALL ATLANTIC
OCEAN BEACHES THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
COLD FRONT WILL PUSH OFFSHORE TONIGHT...AND THEN STALL JUST TO THE
SOUTH. THIS WILL BE THE FOCAL POINT FOR MORE SHOWERS AND
THUNDERSTORMS THROUGH THURSDAY...MAINLY FOR LONG ISLAND AND
SOUTHEAST CT AS THESE AREAS WILL BE CLOSER TO THE FRONT.
COVERAGE WILL ONLY BE ISOLATED HOWEVER.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE BEGINS BUILDING IN THU NIGHT INTO FRI...BUT WITH AN
UPPER TROUGH YET TO PASS THROUGH...LIKE 00Z GFS IDEA OF ISOLD
CONVECTION IN THE HIGHER ELEVATIONS VIA DIFFERENTIAL HEATING LATE
FRI AFTERNOON AND EARLY EVENING AS THE TROUGH SWINGS ACROSS.
EXPECT DRY WX TO CONTINUE THEREAFTER INTO SUNDAY MORNING AS THE HIGH
DOMINATES...AND AS ANY APPROACHING SHORTWAVES SAT NIGHT INTO SUNDAY
MORNING AS WEAK UPPER RIDGING GIVES WAY WILL HAVE INSUFFICIENT
INSTABILITY TO WORK WITH GIVEN THE ONSHORE FLOW OF MARITIME AIR
AROUND THE SOUTHERN PERIPHERY OF THE HIGH.
MEDIUM RANGE NWP MODELS STILL SUGGEST CHANCE OF CONVECTION BEGINNING
LATE DAY SUNDAY MAINLY NORTH/WEST OF NYC AS A SLOW MOVING FRONTAL
SYSTEM APPROACHES...THEN OVERSPREADING THE REGION SUNDAY NIGHT INTO
MON AND CONTINUING INTO TUE. MON COULD BE AN ACTIVE WX DAY IF THE
00Z GFS IS CORRECT...WITH AN APPROACHING SFC WARM FRONT AND MID
LEVEL SHORTWAVE IN A HIGH PW AND LOW CAPE/HIGH SHEAR ENVIRONMENT
THAT COULD BE CONDUCIVE TO FLOODING AND/OR SEVERE WX. TIMING OF ALL
THE INGREDIENTS WILL HAVE TO BE JUST RIGHT...SO GIVEN THE INHERENT
UNCERTAINTY AT THIS TIME RANGE DID NOT OUTLOOK IN HWO.
TEMPS SHOULD REMAIN CLOSE TO SEASONAL AVG.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
TERMINALS FORECASTS ON TRACK...SO NO CHANGES MADE TO THE 12Z TAFS.
OTHERWISE...A PRE-FRONTAL TROUGH SETS UP WEST OF THE TERMINALS
TODAY. BOTH THE TROUGH AND THE TRAILING COLD FRONT MOVE ACROSS THE
TERMINALS TONIGHT.
VFR. WSW-SW FLOW BACKS SSW-S THIS AFTN...WITH SEA BREEZE EAST OF
THE HUDSON. MODERATE CONFIDENCE IN SEA BREEZE DEVELOPMENT/TIMING.
ISO/SCT SHRA/TSTM LATE AFTN AND EVENING HOURS. PROBABILITY AND
CONFIDENCE TOO LOW TO INCLUDE IN TAFS.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: OCCASIONAL GUSTS 21-23 KT POSSIBLE THIS
AFTN. TIMING OF SHIFT TO S COULD BE OFF BY AN HOUR OR TWO.
KLGA FCSTER COMMENTS: TIMING OF SHIFT TO S COULD BE OFF BY AN HOUR
OR TWO.
KEWR FCSTER COMMENTS: CHANCE THAT WIND BACK CLOSER TO 200-180
MAGNETIC FOR AT LEAST A FEW HOURS AFTER AROUND 19Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: CHANCE THAT WIND BACK CLOSER TO 200-180
MAGNETIC FOR AT LEAST A FEW HOURS AFTER AROUND 19Z.
KHPN FCSTER COMMENTS: OCCASIONAL GUSTS 15-18 KT POSSIBLE THIS AFTN.
KISP FCSTER COMMENTS: TIMING OF WIND SHIFT TO S COULD BE OFF BY AN
HOUR OR TWO.
.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
.THU...MORNING SHOWERS WITH MVFR OR LOWER CONDS POSSIBLE EAST OF
THE NYC METRO TERMINALS.
.THU NIGHT-SUNDAY...MAINLY VFR.
&&
.MARINE...
SCA REMAINS IN EFFECT FOR THE OCEAN WATERS THROUGH TODAY...AND
TONIGHT ON THE CENTRAL/EASTERN OCEAN WATERS. WINDS WILL REMAIN
BELOW SCA CONDITIONS THROUGH THE SHORT TERM...BUT OCEAN SEAS
REMAIN ELEVATED AT 5-7 FT TODAY. ONCE A COLD FRONT FRONT PASSES
THROUGH AND HIGH PRESSURE BEGINS TO BUILD IN...OCEAN SEAS WILL
BEGIN TO SUBSIDE...WITH SEAS DROPPING BELOW 5 FT BY TONIGHT W OF
FIRE ISLAND INLET...AND BY THU MORNING FROM FIRE ISLAND INLET TO
MONTAUK. THEN EXPECTING SUB-SCA CONDITIONS ON ALL WATERS THROUGH
THE WEEKEND...WITH INCREASING WINDS/SEAS NEXT WEEK AHEAD OF THE
NEXT FRONT.
&&
.HYDROLOGY...
NO WIDESPREAD SIGNIFICANT QPF OF 1/2 INCH OR MORE EXPECTED THROUGH
THE WEEKEND. WILL HAVE TO KEEP AN EYE ON MON AS A POTENTIAL DAY
FOR SIGNIFICANT RAINFALL AS A WARM FRONT APPROACHES.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ355.
SMALL CRAFT ADVISORY UNTIL 9 AM EDT THURSDAY FOR ANZ350-353.
&&
$$
SYNOPSIS...GOODMAN/JP
NEAR TERM...GOODMAN/JP/SEARS
SHORT TERM...JP
LONG TERM...GOODMAN
AVIATION...MPS
MARINE...GOODMAN/JP
HYDROLOGY...GOODMAN/JP
AREA FORECAST DISCUSSION
NWS TAUNTON MA
703 AM EDT WED JUL 9 2014
.SYNOPSIS...
VERY WARM WEATHER WILL CONTINUE TODAY WITH A FEW AFTERNOON
THUNDERSTORMS POSSIBLE...BUT MAINLY DRY WEATHER WILL PREVAIL FOR
MOST OF THE REGION. MUCH LOWER HUMIDITY AND SEASONABLE WEATHER
RETURN THURSDAY INTO SATURDAY AS HIGH PRESSURE BUILDS IN BEHIND A
DEPARTING COLD FRONT. THE HIGH PRESSURE SYSTEM WILL MOVE OFF THE
COAST EARLY NEXT WEEK ALLOWING HUMIDITY TO RETURN ALONG WITH THE
RISK OF A FEW SHOWERS/ THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
7 AM UPDATE....
VERY WARM START TO THE DAY WITH TEMPS ALREADY IN THE U60S AND L70S
AT 7 AM. CLOUDS ALONG THE COAST THIS MORNING MAY YIELD A BRIEF
SHOWER OR SPRINKLE AS ADDITIONAL SHORT WAVE ENERGY PIVOTS UP THE
COASTLINE IN THE SOUTHWEST FLOW ALOFT. THIS ACTIVITY OFF THE NJ
AND LONG ISLAND COAST MAY CLIP THE SOUTH COAST BUT NOT EXPECT MUCH
MORE THAN SPRINKLES OR A BRIEF SHOWER THRU THIS MORNING.
AS FOR THIS AFTERNOON...LATEST HRRR AND RAP13 FOCUS AFTERNOON
CONVECTION ACROSS NY/NJ AND PA...POSSIBLY SPILLING INTO WESTERN
NEW ENGLAND LATE IN THE DAY. THIS IS CONSISTENT WITH GLOBAL MODELS
THAT INDICATED MID LEVEL DRY AIR ADVECTING ACROSS THE REGION TODAY
IN THE WAKE OF DEPARTING LEAD SHORT WAVE TROUGH AND ASSOCIATED
PREFRONTAL TROUGH FROM LAST NIGHT. THIS MID LEVEL DRY AIR MAY BE DEEP
ENOUGH TO INHIBIT CONVECTION THIS AFTERNOON OR AT LEAST KEEP AREAL
COVERAGE TO ISOLATED. PREVIOUS FORECAST CAPTURES THIS WELL SO NO
MAJOR CHANGES EXPECTED. EARLIER DISCUSSION BELOW.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
BULK OF THE FORECAST REMAINS ON TRACK FOR THIS MORNING. ALL IS QUIET
ON THE RADAR AT THE MOMENT. HOWEVER SEE A FEW CELL DEVELOPING SOUTH
OF NJ ALONG THE NOSE OF THE LOW LEVEL JET. BECAUSE OF THE UPPER 60S
TO LOW 70S DEWPOINTS CURRENTLY ACROSS THE REGION CANNOT RULE OUT A
FEW SCATTERED SHOWERS/THUNDER NEAR DAY BREAK ACROSS THE SOUTHERN
WATERS AND OVER THE CAPE AS LLJ INCREASES.
OTHERWISE THE FOG POTENTIAL SEEMS TO HAVE LIFTED AS GUSTY SW WINDS
CONTINUE EARLY THIS MORNING AT 20-25 MPH.
TODAY...
* HIGH RISK FOR RIP CURRENTS TODAY ACROSS THE SOUTH COAST
INCLUDING THE ISLANDS.*
ANOTHER VERY WARM TO HOT DAY ON TAP FOR THE REGION. ONCE AGAIN
HIGHS ARE EXPECTED TO REACH IN THE UPPER 80S AND LOWER 90S. HOWEVER
IT MAY NOT BE AS MUGGY AS DRY AIR WILL WORK ITS WAY INTO THE
REGION.
UPPER LEVEL TROUGH WILL CONTINUE TO SPIN OVER THE REGION TODAY
BRINGING ANOTHER SHORTWAVE AND ASSOCIATED COLD FRONT ACROSS SOUTHERN
NEW ENGLAND. AS WITH PREVIOUS DAYS...THIS FRONT WILL PROVIDE A
SOURCE OF LIFT FOR THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT.
HOWEVER INSTABILITY VALUES WILL BE LESS THAN YESTERDAY...REACHING
CLOSE TO 1000 J/KG. ALSO DEEP LAYER MOISTURE WILL BE LACKING AS A
GOOD AMOUNT OF MID TO UPPER LEVEL DRY AIR WILL BE PUSHING THROUGH
PER CROSS SECTIONS. THEREFORE IF ANY STORM DOES DEVELOP THERE
UPDRAFTS MAY STRUGGLE TO GROW AND/OR BE LOW-TOPPED. ASIDE FROM THE
LOW INSTABILITY AND LACKING MOISTURE...SHEAR VALUES WILL BE HIGH
WITH 0-6 KM SHEAR VALUES AROUND 40-50 KTS. WITH ALL THAT
SAID...GIVEN VERY HIGH SHEAR AND FRONTAL BOUNDARY SLOWLY WORKING
INTO THE REGION THINK WE WILL SEE ISOLATED STORMS BUT WITH LIMITED
AREAL COVERAGE FROM THE LACK OF MOISTURE. ANY STORM THAT IS ABLE
TO DEVELOP COULD BE STRONG TO SEVERE SO STILL NEED TO KEEP A CLOSE
EYE ON THE POTENTIAL.
FINALLY...PERSISTENT SOUTHWESTERLY FLOW WILL GENERATE MODEST TO
LARGE WAVE ACTION LEADING TO A HIGH RISK FOR DANGEROUS RIP
CURRENTS ALONG OCEAN EXPOSED BEACHES OF THE SOUTH COAST...AS WELL
AS THE ISLANDS DURING THE DAY. BEACHGOERS SHOULD USE CAUTION IF
VENTURING INTO THE WATER TODAY.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...
FRONT WILL CONTINUE TO SLOWLY WORK ITS WAY ACROSS SOUTHERN NEW
ENGLAND TONIGHT BEFORE STALLING JUST SOUTH OF THE CAPE AND ISLANDS.
AS DRY AIR WORKS IN BEHIND THE FRONT ANTICIPATE THE STORM THREAT TO
DIMINISH IN THAT REGION...HOWEVER IT MAY LINGER ACROSS THE CAPE
AND THE ISLANDS ESPECIALLY WHEN THE LLJ INCREASES OVERNIGHT.
FOG AND LOW LEVEL CLOUDS MAY ALSO PERSIST ACROSS THE CAPE AND
ISLANDS OVERNIGHT DUE TO LOW TEMP/DEWPOINT SPREAD.
TOMORROW...
FRONT WILL CONTINUE TO LINGERING SOUTH OF THE CAPE AND ISLANDS
TOMORROW ALLOWING FOR A SLIGHT CHANCE FOR SHOWERY WEATHER. OTHERWISE
DRY AIR WILL CONTINUE TO WORK INTO THE REGION ALLOWING FOR LESS
MUGGY CONDITIONS. TEMPERATURES WILL ALSO BE A TAD COOLER WITH HIGHS
REACHING ONLY IN THE LOW TO MID 80S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* DRIER/LESS HUMID WEATHER & SEASONABLE TEMPS FRI AND SAT
* BECOMING MORE HUMID ALONG WITH A RISK OF SHOWERS/T-STORMS SUN AND
ESPECIALLY EARLY NEXT WEEK
OVERVIEW AND MODEL PREFERENCES...THIS PERIOD FEATURES A RATHER
ROBUST NORTHERN STREAM PATTERN WITH A TRANSITION TOWARD A DRIER/LESS
HUMID AIRMASS BEGINNING EARLY THIS PERIOD. THEN LATER THIS WEEKEND
AND INTO EARLY NEXT WEEK A PIECE OF THE POLAR VORTEX OVER NORTHERN
CANADA DESCENDS EQUATORWARD INTO SOUTHERN ONTARIO AND QUEBEC. THIS
YIELDS AN ANOMALOUSLY COOL TROUGH OVER THIS AREA. GEFS ENSEMBLES
INDICATE 500MB HEIGHTS AND 850 TEMPS ON THE ORDER OF -2 SD BELOW
CLIMO ASSOCIATED WITH THIS TROUGH EARLY NEXT WEEK. TRANSITIONING TO
THIS PATTERN WILL YIELD A CHANCE OF SHOWER/T-STORMS ACROSS NEW
ENGLAND FROM SUNDAY INTO EARLY NEXT WEEK.
DETAILS...
THURSDAY NIGHT...COLD FRONT WILL BE MOVING OFFSHORE AS TRAILING
SHORT WAVE TROUGH KICKS OUT ANY LINGERING SHOWERS OVER CAPE COD AND
THE ISLANDS WITH DRIER/LESS HUMID AIRMASS SLOWLY OVERSPREADING THE
REGION FROM NORTHWEST TO SOUTHEAST.
FRIDAY...CORE OF COOLER/LESS HUMID AIRMASS WILL BE OVER THE REGION
DURING THIS TIME. REAL PLEASANT CONDITIONS FOR EARLY TO MID JULY
WITH LIGHT WINDS AND DEW PTS IN THE 50S. HIGH PRES OVERHEAD WHICH
WILL SUPPORT AFTERNOON SEABREEZES.
SAT...DRY/COMFORTABLE WEATHER CONTINUES WITH HIGH PRES ALONG THE NEW
ENGLAND COAST. TEMPS IN THE U50S AND L60S BEFORE SUNRISE WILL CLIMB
TO 80-85 INLAND WITH MU70S ALONG THE COAST.
SUNDAY...WARM AND SLIGHTLY MORE HUMID AS RETURN FLOW SETS UP AS HIGH
PRES MOVES FARTHER OFFSHORE.
MONDAY/TUESDAY...CHANCE OF SHOWERS/T-STORMS AS LEAD SHORT WAVE
TROUGH AND ASSOCIATED COLD FRONT AHEAD OF POLAR VORTEX SWEEPS ACROSS
NEW ENGLAND. BECOMING MORE HUMID GIVEN THE MOIST INFLOW OFF THE ATLC
INTO SOUTHERN NEW ENGLAND.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...
7 AM UPDATE...NO MAJOR CHANGES FROM PREVIOUS FORECAST. EARLIER
DISCUSSION BELOW.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TODAY AND TONIGHT...MODERATE CONFIDENCE. LOW CLOUDS AND FOG ALONG
SOUTHEAST NEW ENGLAND COAST WILL BURN OFF TEMPORARILY DURING THE
LATE MORNING AND AFTERNOON...BUT SHOULD REFORM TONIGHT. ACROSS
THE REST OF THE REGION MAINLY VFR OUTSIDE A FEW SPOT THUNDERSTORMS
THIS AFTERNOON AND EVENING.
THURSDAY...HIGH CONFIDENCE. VFR CONDITIONS EXPECT ACROSS THE CAPE
AND ISLAND WHERE LINGERING MVFR CLOUDS AND FOG WILL OCCUR.
KBOS TAF...HIGH CONFIDENCE IN TAF.
KBDL TAF...HIGH CONFIDENCE IN TAF.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...
THURSDAY NIGHT...TREND TOWARD VFR...EXCEPT MVFR POSSIBLE IN LOW
CLOUDS...SHRA/TSRA EARLY ALONG THE SOUTH COAST.
FRIDAY THROUGH SUNDAY...HIGH CONFIDENCE FOR DRY WEATHER AND VFR. THE
EXCEPTION MAY BE ACROSS THE INTERIOR SUNDAY WHEN MVFR/IFR POSSIBLE
IN SHRA/TSRA.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /TODAY THROUGH THURSDAY/...MODERATE TO HIGH
CONFIDENCE.
GUSTY SOUTHWEST WINDS WILL CONTINUE EARLY THIS MORNING ACROSS THE
NEAR SHORE WATERS...SO THESE SCA HEADLINES WILL CONTINUE INTO THE
MORNING HOURS. MEANWHILE...ACROSS THE SOUTHERN OPEN WATERS LONG
SOUTHWEST FETCH WILL ALLOW PERSISTENT 4 TO 7 FOOT SEAS INTO AT LEAST
WEDNESDAY EVENING.
IN ADDITION...AREAS OF FOG ARE EXPECTED AGAIN LATE TONIGHT INTO
THURSDAY MORNING ACROSS THE SOUTHERN WATERS. THERE ALSO IS A LOW
RISK OF A STRONG THUNDERSTORM OR TWO WITH GUSTY WINDS ACROSS THE
EASTERN WATERS THIS LATE THIS AFTERNOON INTO THE OVERNIGHT HOURS.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...
THURSDAY NIGHT...LOW RISK OF A FEW LEFTOVER SHOWERS/T-STORMS
ACROSS THE SOUTHERN WATERS DURING THE EVENING. OTHERWISE TREND
TOWARD CLEARING SKIES AS COLD FRONT MOVES OFFSHORE.
FRIDAY THROUGH SUNDAY...HIGH CONFIDENCE AS HIGH PRESSURE BUILDS INTO
THE REGION RESULTING IN LIGHT WINDS AND SEAS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR
ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ250.
SMALL CRAFT ADVISORY UNTIL NOON EDT THURSDAY FOR ANZ254>256.
&&
$$
SYNOPSIS...NOCERA/DUNTEN
NEAR TERM...NOCERA/DUNTEN
SHORT TERM...DUNTEN
LONG TERM...NOCERA
AVIATION...NOCERA/DUNTEN
MARINE...NOCERA/DUNTEN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
747 PM EDT THU JUL 10 2014
.SYNOPSIS...
A STATIONARY FRONTAL BOUNDARY WILL REMAIN OVER THE DELMARVA TONIGHT
BEFORE SLOWLY PUSHING SOUTH OF THE AREA FRIDAY. HIGH PRESSURE BUILDS
IN FROM THE NORTHEAST FRIDAY INTO SATURDAY. RETURN FLOW DEVELOPS
LATE IN THE WEEKEND AND EARLY NEXT WEEK AS HIGH PRESSURE MOVES
OFFSHORE AND AN STRONG UPPER LOW DIGS INTO THE UPPER MIDWEST. A COLD
FRONT WILL APPROACH THE EASTERN SEABOARD TUESDAY BEFORE MOVING
OFFSHORE BY WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
BACKDOOR COLD FRONT HAS CLEARED OUR CWA. BUT WITH TROFFING ALOFT,
THERE IS STILL SUFFICIENT INSTABILITY FOR SHOWERS AND
THUNDERSTORMS TO FORM. IF 7/8/14 WAS THE DAY THE HRRR AND COSPA
RAN TO THEIR AGENT AND RENEGOTIATE THEIR CONTRACTS, TODAY IS THE DAY
TO BE THANKFUL THE REVERSE CANT BE DONE. DIFFICULT MORE SUBTLE SCENARIO
WITH NONE OF THE MESOSCALE MODELS HANDLING/VERIFYING CONVECTION
WELL AND FALLING OFF TRACK RATHER QUICKLY WITHIN OUR CWA. WITH
SHORT WAVES STILL PROGGED TO PROGRESS THROUGH THE TROF, SFC BASED
INSTABILITY EXCEEDING 2K JOULES WEST, BOUNDARIES PROVIDING LIFT,
WE ARE GOING TO KEEP THE PRESENT FORECAST, WATCH, GOING UNTIL WE
SEE WHAT COMES OF THE CONVECTION EXITING THE ALLEGHENIES. ANY ESTF
UPDATES ARE GOING TO BE BASED ON ADJUSTING FOR TEMPS WHERE PCPN IS
OR JUST RECENTLY HAS OCCURRED.
A FLASH FLOOD WATCH HAS BEEN ISSUED FOR OUR DELMARVA AND SOUTHERN
NEW JERSEY COUNTIES WHERE IT HAS RAINED HEAVILY DURING THE DAY
TODAY, AND THE POTENTIAL FOR ADDITIONAL HEAVY RAIN EXISTS.
PW VALUES REMAIN HIGH WITH VALUES 1.75-2 INCHES ACROSS THE AREA.
MEANWHILE, THE MID-LEVEL TROUGH CONTINUES TO APPROACH THE AREA
FROM THE WEST AND SEVERAL VORTICITY IMPULSES WILL CONTINUE TO
SLIDE ACROSS THE AREA THROUGH THIS EVENING. ALL OF THIS COMBINED
WILL HELP ADDITIONAL SHOWERS AND THUNDERSTORMS DEVELOP. IT HAS
ALREADY RAINED ACROSS PORTIONS OF THE WATCH AREA TODAY, AND WHERE
IT HAS RAINED, IT`S BEEN VERY HEAVY WITH UP TO 3-4 INCHES IN SOME
AREAS IN AN HOUR OR TWO. WITH THE POTENTIAL FOR ADDITIONAL HEAVY
RAINFALL ACROSS THESE AREAS, WE HAVE ISSUED A FLASH FLOOD WATCH
THROUGH THIS EVENING.
THERE ARE SCATTERED SHOWERS AND THUNDERSTORMS MOVING THROUGH CENTRAL
AND NORTHEASTERN PENNSYLVANIA, THROUGH THESE HAVE BEEN MOVING AND
WILL LIKELY BE MORE DIURNAL IN NATURE AND SHOULD DISSIPATE AROUND
SUNSET; SO NO WATCH FURTHER NORTH.
WE EXPECT MUCH OF THE PRECIPITATION TO BEGIN TO DIMINISH LATER THIS
EVENING AND TOWARD MIDNIGHT AS INSATIABILITY WANES AND PW VALUES
BEGIN TO LOWER. THEREFORE THE WATCH ENDS AT LOCAL MIDNIGHT. HOWEVER,
WITH THE FRONT REMAINING NEARBY AND THE MID-LEVEL TROUGH STILL TO
OUR WEST, THERE WILL STILL BE THE POTENTIAL FOR A FEW SHOWERS AND
THUNDERSTORMS INTO FRIDAY MORNING.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
THE PESKY FRONTAL BOUNDARY IS EXPECTED TO PUSH BACK OFFSHORE ON
FRIDAY, AND STALL ACROSS THE OCEAN WATERS TO OUR EAST. PW VALUES
CONTINUE TO LOWER THROUGH THE DAY, BUT THE MID-LEVEL THROUGH WILL BE
MOVING OVERHEAD THROUGH THE DAY. THERE WILL REMAIN THE CHANCE FOR
ISOLATED-SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE AREA, WITH
THE BEST POTENTIAL ACROSS SOUTHERN NEW JERSEY AND SOUTHERN DELMARVA.
HIGHS ON FRIDAY WILL DEPEND ON HOW MUCH SUNSHINE WE GET, WITH CLOUDY
AREAS LIKELY BEING CLOSER TO THE COOLER MET GUIDANCE AND SUNNIER
AREAS CLOSER TO THE WARMER MAV GUIDANCE. FOR NOW, WE TOOK A BLEND OF
THE MAV/MET/MOSGUIDE FOR DAYTIME HIGHS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
SURFACE HIGH PRESSURE CENTERED JUST EAST OF NEW ENGLAND WILL PROVIDE
NICE WEATHER THROUGH SATURDAY. FRIDAY NIGHT WILL FEATURE CLEAR SKIES
AND COOL TEMPERATURES FOR THIS TIME OF YEAR, AND AN EASTERLY FLOW
WILL KEEP HIGHS IN THE 80S ON SATURDAY. CONDITIONS WILL BEGIN TO
DETERIORATE SOMEWHAT ON SUNDAY AS A FRONTAL BOUNDARY APPROACHES FROM
THE WEST. CLOUDS WILL BE ON THE INCREASE AND SHOWERS AND
THUNDERSTORM ACTIVITY WILL BECOME INCREASINGLY LIKELY FROM WEST TO
EAST AS THE DAY WEARS ON. THESE CLOUDS SHOULD KEEP THE HIGH
TEMPERATURES ON SUNDAY ONE OR TWO DEGREES COOLER THAN SATURDAY.
AN ANOMALOUSLY STRONG NRN STREAM CLOSED LOW IS FORECAST TO DIVE SOUTHWARD
FROM NEAR HUDSON BAY INTO THE UPPER MIDWEST EARLY NEXT WEEK, SETTING
UP A RATHER UNUSUAL PATTERN FOR THIS TIME OF YEAR. THE MID-ATLANTIC
REGION WILL BE SITUATED IN AN INCREASINGLY DIFFLUENT FLOW PATTERN
ALOFT ON THE SOUTHEASTERN PERIPHERY OF THE AMPLIFYING UPPER TROUGH
AND ON THE WESTERN PERIPHERY OF THE WESTERN ATLANTIC RIDGE. THE HEAT
AND HUMIDITY WILL RETURN MONDAY AND TUESDAY DURING THIS TIME AS
STRENGTHENING SOUTHWESTERLY FLOW AHEAD OF THE LOW BECOMES
ESTABLISHED OVER THE EASTERN CONUS. MAX TEMPS IN THE LOWER 90S
APPEAR LIKELY MONDAY AND TUESDAY. LEANED TOWARD THE SLOWER ECMWF
SOLUTION REGARDING THE ARRIVAL OF THE FROPA ON TUESDAY. RAISED MAX
TEMPS A FEW DEGREES FROM 12Z WPC GUIDANCE AS A SLOWER SOLUTION WOULD
KEEP THE PRE-FRONTAL WARM AIRMASS THAT IS CHARACTERIZED BY 850 MB
TEMPS NEAR 20C OVER THE AREA INTO TUESDAY. MAX TEMPS IN THE LOWER
90S OVER THE COASTAL MID-ATLANTIC REGION FOR ONE MORE DAY.
MONDAY AND TUESDAY BOTH LOOK TO BE A RATHER STORMY PERIOD FOR THE
AREA. THE FOCUS FOR CONVECTION APPEARS TO BE A PRE-FRONTAL/LEE
TROUGH ON MONDAY AND THE MAIN COLD FRONT FOR TUESDAY. FAVORABLE
DYNAMICS IN THE RIGHT ENTRANCE REGION OF AN UNSEASONABLY STRONG
UPPER-LEVEL JET STREAK AND AHEAD OF THE APPROACHING LONGWAVE TROUGH
ALSO LOOKS TO CONTRIBUTE TO SYNOPTIC LIFT OVER THE AREA ON TUESDAY.
THERE ARE STILL PLENTY OF DETAILS THAT NEED TO BE WORKED OUT THIS
FAR OUT, BUT THE POTENTIAL IS THERE FOR SEVERE THUNDERSTORM EVENTS
BOTH DAYS. SPC HAS DEPICTED THE AREA IN A DAY 6 SLIGHT RISK FOR
TUESDAY.
COLD FROPA LIKELY TUESDAY NIGHT OR EARLY WEDNESDAY. MUCH COOLER
AND DRIER CONDITIONS ARE FORECAST TO RETURN BEHIND THE COLD FRONT
BY WEDNESDAY. THE 12Z ECMWF INDICATES H8 TEMPS DROPPING INTO THE
SINGLE DIGITS BEHIND THE FRONT.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
00Z TAFS CARRY SOME MVFR CONDITIONS INLAND AT FOGGIER TERMINALS
AND IFR CIGS AT COASTAL TERMINALS LATER TONIGHT.
FOR THIS EVENING, CONVECTION IN THE SUSQUEHANNA VALLEY IS ONLY
SLOWLY DRIFTING EASTSOUTHEAST. SHOWERS INCLUDED AT KRDG INITIALLY,
ALTHOUGH KILG MIGHT NEED AN AMENDMENT IF THEY STAY TOGETHER
LONGER THAN ANTICIPATED. OTHERWISE NON COASTAL TERMINALS SHOULD
HAVE VFR CONDITIONS WITH MAINLY MID LEVEL CIGS OR HIGHER AND LIGHT
EAST WINDS. AT THE COAST, CONFIDENCE IS LESS THAN AVERAGE, BUT
WITH RAIN OFFSHORE AND ONSHORE WIND, WE ARE PREDICTING AN IFR CIG
TO FORM AT THE TERMINALS.
OVERNIGHT, PRIMARILY VFR CONDITIONS WITH SOME MVFR RESTRICTIONS
DUE TO FOG AT SMALLER AIRPORTS AND TERMINALS. ANY CIG SHOULD BE
VFR MID LEVEL OR HIGHER. WINDS WILL BE LIGHT. AT THE COASTAL
TERMINALS (KACY AND KMIV), WE WILL CONTINUE THE IFR CIG WITH SOME
MVFR VSBY RESTRICTIONS. CONFIDENCE LESS THAN AVERAGE.
ON FRIDAY VFR CONDITIONS EXPECTED OR WILL BE REACHED (AT THE COASTAL
TERMINALS) AT ALL AIRPORTS DURING THE MORNING. PCPN CHANCES
OVERALL ARE LESS THAN TODAY AND NO MENTION WILL BE MADE. SOME
CUMULUS CLOUDS SHOULD FORM, BUT NOT EXPECTING A VFR CIG. WINDS
WILL BE LIGHT FROM THE EAST AND A BAY AND SEA BREEZE FRONT SHOULD
FORM. NOT SURE IF A VERY SHARP DISCONTINUITY WILL FORM AS THE
GENERAL WIND FIELD SHOULD BE FROM THE EAST.
OUTLOOK...
FRIDAY NIGHT THRU SATURDAY NIGHT...POTENTIAL FOR IFR CIGS WITH
MARINE STRATUS TO IMPACT TERMINALS, PARTICULARLY ACY/MIV, FRIDAY AND
SATURDAY NIGHTS WITH ONSHORE FLOW. OTHERWISE VFR EXPECTED WITH DRY
CONDITIONS.
SUNDAY AND MONDAY...CHANCE FOR SHRA/TSRA BOTH DAYS. BETTER CHANCE
MAY BE MONDAY WITH A WELL-DEFINED SFC TROUGH DEVELOPING OVER THE
EASTERN SEABOARD. LOCAL/BRIEF RESTRICTIONS POSSIBLE.
TUESDAY...BETTER CHANCE FOR SHRA/TSRA TUESDAY AS A COLD FRONT
APPROACHES.
&&
.MARINE...
SUB-ADVISORY CONDITIONS ARE EXPECTED THROUGH TONIGHT AND FRIDAY WITH
A FRONTAL BOUNDARY DRAPED ACROSS THE WATERS. THERE REMAINS A CHANCE
FOR SHOWERS AND THUNDERSTORMS THROUGH FRIDAY; EXPECT HIGHER WINDS
AND WAVES NEAR THUNDERSTORMS.
OUTLOOK...
FRIDAY NIGHT THROUGH AND SATURDAY NIGHT...HIPRES BUILDS IN FROM THE
NORTHEAST STATES TO START THE WEEKEND. ONSHORE FLOW WILL BE LIGHT.
SUNDAY THROUGH TUESDAY...WINDS VEER, BECOMING SOUTHWESTERLY ON SUNDAY.
SOUTHWEST WINDS STRENGTHEN MONDAY BUT SHOULD REMAIN BELOW SCA
LEVELS. GUSTY SOUTHERLY WINDS AHEAD OF A COLD FRONT ON TUESDAY.
MARGINAL SCA POSSIBLE. CHANCE FOR SHRA/TSRA LATE SUNDAY. BETTER
CHANCE ON MONDAY AND TUESDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NJZ016-
021>024.
DE...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR DEZ001>004.
MD...FLASH FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR MDZ008-012-
015-019-020.
MARINE...NONE.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GIGI/ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...KLEIN/MIKETTA
AVIATION...GIGI/KLEIN
MARINE...KLEIN/ROBERTSON
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
523 AM EDT WED JUL 9 2014
.SYNOPSIS...
LOW PRESSURE WILL CONTINUE TO MOVE ACROSS EASTERN CANADA THROUGH
THURSDAY, WHICH WILL PULL ANOTHER COOL FRONT ACROSS OUR AREA LATER
TODAY. THIS FRONT WILL THEN SETTLE TO OUR SOUTH THURSDAY. HIGH
PRESSURE WILL THEN BRIEFLY BUILD ACROSS THE NORTHEAST FRIDAY INTO
SATURDAY, BEFORE IT SLIDES OFFSHORE DURING SATURDAY. THE NEXT COLD
FRONT IS SCHEDULED TO ARRIVE LATER MONDAY INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INITIAL COLD FRONT IS VERY HARD TO DISTINGUISH NOW, WHICH MAKES IT
ALL THE HARDER TO FIGURE OUT WHERE CONVECTION WILL DEVELOP TODAY.
ALTHOUGH TODAY IS NOT EXPECTED TO BE AS WARM AS YESTERDAY, THUS
SOMEWHAT LIMITING THE INSTABILITY, ML CAPE VALUES ABOVE 500 J/KG,
LI LESS THAN ZERO, AND 0-6KM BULK SHEAR BETWEEN 30 AND 40KT WILL
STILL BE ENOUGH TO SUPPORT SOME SUSTAINED UPDRAFTS, IF THERE IS
CONFLUENCE AT THE SURFACE. THE QUESTION WILL JUST BE WHERE THE
CONFLUENCE WILL BE, AS REMNANT OUTFLOW BOUNDARIES FROM LAST
NIGHT/S CONVECTION AND THE LEFT OVER TROUGH AXIS FROM YESTERDAY
ARE THE MOST LIKELY CANDIDATES TO PROVIDE LOW LEVEL CONVERGENCE,
BUT ARE POORLY DEFINED AT THIS TIME.
AS FAR AS SEVERE THREAT...AS MENTIONED BEFORE, THE INSTABILITY WILL
BE LIMITED ESPECIALLY AS COMPARED TO YESTERDAY, BUT THE HIGHER SHEAR
VALUES COULD HELP TO SUSTAIN UPDRAFTS ENOUGH TO SUPPORT SMALL HAIL.
IN ADDITION, MODEL SOUNDINGS FROM BOTH THE GFS AND RAP SHOW A DRY
LAYER BY THIS AFTERNOON AROUND 400 TO 500 MB. THIS COULD FURTHER
ENHANCE THE DOWNBURST THREAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
MUCH OF THE REGION WILL FINALLY SEE A SHIFT TO NORTHWESTERLY WINDS
TONIGHT HERALDING DRY AND COLD AIR ADVECTION. THUS, SHOULD SEE MOST
CONVECTION WIND DOWN BY MIDNIGHT, WITH THE EXCEPTION OF CLOSER TO
THE SHORE WHICH WILL SEE A LATER ARRIVAL OF THE COOLER AND DRIER
AIR. WITHIN THE WARM SECTOR, THERE WILL REMAIN AT LEAST ELEVATED
INSTABILITY FOR MUCH OF THE NIGHT.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
THE OVERALL SYNOPTIC SETUP IS COMPRISED OF AN UPPER-LEVEL TROUGH
FROM SOUTHEASTERN CANADA TO THE MID ATLANTIC REGION. THIS FEATURE IS
FORECAST TO GRADUALLY LIFT OUT THROUGH LATE FRIDAY, HOWEVER ANOTHER
TROUGH THEN AMPLIFIES ACROSS THE MIDWEST AND GREAT LAKES REGION.
THIS WILL GENERALLY KEEP OUR AREA UNDER A CYCLONIC FLOW REGIME WITH
A COLD FRONT OR TWO SETTLING SOUTHEASTWARD WITH TIME. WE USED A
MODEL BLEND THURSDAY INTO SATURDAY, THEN BLENDED THE 00Z WPC
GUIDANCE INTO CONTINUITY.
FOR THURSDAY AND FRIDAY...A COOL FRONT LOOKS TO BE DRAPED NEAR OUR
SOUTHEASTERN ZONES THURSDAY BEFORE TENDING TO DISSIPATE FRIDAY.
THERE IS THE PRESENCE OF THE UPPER-LEVEL TROUGH, THEREFORE A FEW
SHOWERS AND THUNDERSTORMS ARE POSSIBLE ESPECIALLY THURSDAY. THE
BETTER CHC APPEARS TO BE ACROSS THE SOUTHERN ZONES GIVEN THE
PROXIMITY OF THE LINGERING FRONT AND SOME DEEPER MOISTURE. HIGH
PRESSURE STARTS TO BUILD IN FRIDAY, HOWEVER IT SHOULD THEN BE
SHIFTING TO NEAR THE SOUTHERN NEW ENGLAND COAST AT NIGHT. THIS WILL
DEVELOP AN ONSHORE FLOW, HOWEVER IT IS NOT ALL THAT CERTAIN HOW MUCH
DEEPER MOISTURE REMAINS AS THIS OCCURS.
FOR SATURDAY AND SUNDAY...AS HIGH PRESSURE SLIPS OFF THE
SOUTHEASTERN NEW ENGLAND COAST SATURDAY MORNING, THE FLOW SHOULD
TURN FROM EAST-SOUTHEAST TO MORE SOUTHERLY. AS THIS OCCURS, SOME WAA
MAY ALLOW A LINGERING BOUNDARY TO OUR SOUTH TO LIFT BACK NORTH AS A
WARM FRONT. OVERALL WHILE SATURDAY LOOKS TO BE DRY, AN ISOLATED
SHOWER OR THUNDERSTORM CANNOT BE RULED OUT DURING PEAK HEATING
ESPECIALLY INLAND NORTH OF A POSSIBLE WARM FRONTAL FEATURE. AS THE
UPPER-LEVEL FLOW STARTS TO TURN MORE CYCLONIC SUNDAY, SOME SHOWERS
AND THUNDERSTORMS MAY DEVELOP ESPECIALLY INLAND IN THE AFTERNOON
PROBABLY TIED TO A LEE SIDE TROUGH. OVERALL, WE USED A 50/50 BLEND
OF CONTINUITY AND WPC GUIDANCE.
FOR MONDAY AND TUESDAY...A SIGNIFICANT UPPER-LEVEL TROUGH MAY SLIDE
ACROSS THE GREAT LAKES REGION. THIS WILL DRIVE LOW PRESSURE WELL TO
OUR NORTH, HOWEVER THE ASSOCIATED COLD FRONT WILL ARRIVE INTO OUR
AREA AROUND THE LATE MONDAY INTO TUESDAY TIME FRAME. THERE SHOULD BE
DECENT INSTABILITY AHEAD OF THIS FEATURE AS DEEPER MOISTURE ADVECTS
NORTHEASTWARD IN ADVANCE OF THE SURFACE FRONT, AND ALSO INCREASING
CYCLONIC FLOW. THIS COULD RESULT IN SOME STRONGER CONVECTIVE CELLS,
HOWEVER THE SEVERE WEATHER THREAT WILL DEPEND ON THE TIMING OF THE
LARGE SCALE FORCING AND ORGANIZATION AS WELL AS THE ACTUAL
INSTABILITY. AS OF NOW, MONDAY MAY HAVE A HIGHER CHC OF CONVECTION
ESPECIALLY ACROSS OUR WESTERN ZONES. WE KEPT CHC POPS AS A RESULT.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
MOSTLY VFR CONDITIONS ARE EXPECTED...WITH THE FOLLOWING EXCEPTIONS.
PATCHY BR RESULTING IN VISIBILITIES OF 2 TO 3 MILES IS STILL
EXPECTED TO DEVELOP THROUGH 12Z THIS MORNING. BY 18Z, COULD BEGIN TO
SEE ISOLATED TSRA DEVELOPMENT ACROSS THE REGION. THE HIGHEST CHANCES
FOR TSRA LOOK TO BE AT KABE, KRDG, KACY, AND KMIV...THOUGH EVEN AT
THESE LOCATIONS, CHANCE FOR DEVELOPMENT IS TOO LOW AND COVERAGE IS
EXPECTED TO BE TOO LIMITED TO INCLUDE IN THE TAFS AT THIS TIME.
EXPECT A WIND SHIFT TO NORTHWESTERLY WINDS AFTER 00Z TONIGHT,
BRINGING IN DRIER AIR AND DECREASING THE CHANCES FOR ANY MORE BR
DEVELOPMENT.
OUTLOOK...
THURSDAY AND FRIDAY...A FEW SHOWERS AND THUNDERSTORMS SHOULD BE
AROUND MAINLY THURSDAY WITH LOCALLY SUB-VFR CONDITIONS. OTHERWISE,
MAINLY VFR.
SATURDAY AND SUNDAY...SOME SHOWERS AND THUNDERSTORMS POSSIBLE
ESPECIALLY SUNDAY AFTERNOON AND EVENING, RESULTING IN BRIEF
SUB-VFR CONDITIONS.
&&
.MARINE...
THOUGH WINDS WILL CONTINUE TO SUBSIDE OVER THE NEXT FEW HOURS, HAVE
NOT MADE ANY CHANGES TO THE EXPIRATION TIME OF THE SCA ON THE OCEAN
WATERS AS SEAS AT BUOY 44009 REMAIN NEAR 6 FT AND WILL BE SLOW TO
DIMINISH. ONCE SEAS DO DIMINISH, EXPECT BOTH WINDS AND SEAS TO
REMAIN BELOW SCA CRITERIA THROUGH TONIGHT. HOWEVER, SOME
THUNDERSTORMS THIS AFTERNOON AND EVENING WILL BE CAPABLE OF STRONG
GUSTY WINDS.
OUTLOOK...
THURSDAY...A FRONTAL BOUNDARY LOOKS TO LINGER NEAR THE SOUTHERN
WATERS, HOWEVER SUB-ADVISORY CONDITIONS ARE ANTICIPATED.
FRIDAY AND SATURDAY...HIGH PRESSURE ARRIVES FRIDAY THEN SHIFTS OFF
THE SOUTHEASTERN NEW ENGLAND COAST FRIDAY NIGHT AND SATURDAY. THIS
MAY RESULT IN AN ONSHORE FLOW THAT STRENGTHENS SOME FOR A TIME
BEFORE TURNING MORE SOUTHERLY. IT APPEARS THOUGH THAT THE CONDITIONS
WILL REMAIN BELOW ADVISORY CRITERIA.
SUNDAY...A WARM FRONT MAY NEAR OUR SOUTHERN WATERS, HOWEVER THE FLOW
LOOKS WEAK ENOUGH TO KEEP CONDITIONS BELOW ADVISORY CRITERIA.
&&
.RIP CURRENTS...
THE THREAT FOR RIP CURRENTS ALONG THE NEW JERSEY SHORE IS MODERATE
TODAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
ANZ450>455.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...GORSE
AVIATION...GORSE/JOHNSON
MARINE...GORSE/JOHNSON
RIP CURRENTS...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
340 AM EDT WED JUL 9 2014
.SYNOPSIS...
LOW PRESSURE WILL CONTINUE TO MOVE ACROSS EASTERN CANADA THROUGH
THURSDAY, WHICH WILL PULL ANOTHER COOL FRONT ACROSS OUR AREA LATER
TODAY. THIS FRONT WILL THEN SETTLE TO OUR SOUTH THURSDAY. HIGH
PRESSURE WILL THEN BRIEFLY BUILD ACROSS THE NORTHEAST FRIDAY INTO
SATURDAY, BEFORE IT SLIDES OFFSHORE DURING SATURDAY. THE NEXT COLD
FRONT IS SCHEDULED TO ARRIVE LATER MONDAY INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INITIAL COLD FRONT IS VERY HARD TO DISTINGUISH NOW, WHICH MAKES IT
ALL THE HARDER TO FIGURE OUT WHERE CONVECTION WILL DEVELOP TODAY.
ALTHOUGH TODAY IS NOT EXPECTED TO BE AS WARM AS YESTERDAY, THUS
SOMEWHAT LIMITING THE INSTABILITY, ML CAPE VALUES ABOVE 500 J/KG,
LI LESS THAN ZERO, AND 0-6KM BULK SHEAR BETWEEN 30 AND 40KT WILL
STILL BE ENOUGH TO SUPPORT SOME SUSTAINED UPDRAFTS, IF THERE IS
CONFLUENCE AT THE SURFACE. THE QUESTION WILL JUST BE WHERE THE
CONFLUENCE WILL BE, AS REMNANT OUTFLOW BOUNDARIES FROM LAST
NIGHT/S CONVECTION AND THE LEFT OVER TROUGH AXIS FROM YESTERDAY
ARE THE MOST LIKELY CANDIDATES TO PROVIDE LOW LEVEL CONVERGENCE,
BUT ARE POORLY DEFINED AT THIS TIME.
AS FAR AS SEVERE THREAT...AS MENTIONED BEFORE, THE INSTABILITY WILL
BE LIMITED ESPECIALLY AS COMPARED TO YESTERDAY, BUT THE HIGHER SHEAR
VALUES COULD HELP TO SUSTAIN UPDRAFTS ENOUGH TO SUPPORT SMALL HAIL.
IN ADDITION, MODEL SOUNDINGS FROM BOTH THE GFS AND RAP SHOW A DRY
LAYER BY THIS AFTERNOON AROUND 400 TO 500 MB. THIS COULD FURTHER
ENHANCE THE DOWNBURST THREAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
MUCH OF THE REGION WILL FINALLY SEE A SHIFT TO NORTHWESTERLY WINDS
TONIGHT HERALDING DRY AND COLD AIR ADVECTION. THUS, SHOULD SEE MOST
CONVECTION WIND DOWN BY MIDNIGHT, WITH THE EXCEPTION OF CLOSER TO
THE SHORE WHICH WILL SEE A LATER ARRIVAL OF THE COOLER AND DRIER
AIR. WITHIN THE WARM SECTOR, THERE WILL REMAIN AT LEAST ELEVATED
INSTABILITY FOR MUCH OF THE NIGHT.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
THE OVERALL SYNOPTIC SETUP IS COMPRISED OF AN UPPER-LEVEL TROUGH
FROM SOUTHEASTERN CANADA TO THE MID ATLANTIC REGION. THIS FEATURE IS
FORECAST TO GRADUALLY LIFT OUT THROUGH LATE FRIDAY, HOWEVER ANOTHER
TROUGH THEN AMPLIFIES ACROSS THE MIDWEST AND GREAT LAKES REGION.
THIS WILL GENERALLY KEEP OUR AREA UNDER A CYCLONIC FLOW REGIME WITH
A COLD FRONT OR TWO SETTLING SOUTHEASTWARD WITH TIME. WE USED A
MODEL BLEND THURSDAY INTO SATURDAY, THEN BLENDED THE 00Z WPC
GUIDANCE INTO CONTINUITY.
FOR THURSDAY AND FRIDAY...A COOL FRONT LOOKS TO BE DRAPED NEAR OUR
SOUTHEASTERN ZONES THURSDAY BEFORE TENDING TO DISSIPATE FRIDAY.
THERE IS THE PRESENCE OF THE UPPER-LEVEL TROUGH, THEREFORE A FEW
SHOWERS AND THUNDERSTORMS ARE POSSIBLE ESPECIALLY THURSDAY. THE
BETTER CHC APPEARS TO BE ACROSS THE SOUTHERN ZONES GIVEN THE
PROXIMITY OF THE LINGERING FRONT AND SOME DEEPER MOISTURE. HIGH
PRESSURE STARTS TO BUILD IN FRIDAY, HOWEVER IT SHOULD THEN BE
SHIFTING TO NEAR THE SOUTHERN NEW ENGLAND COAST AT NIGHT. THIS WILL
DEVELOP AN ONSHORE FLOW, HOWEVER IT IS NOT ALL THAT CERTAIN HOW MUCH
DEEPER MOISTURE REMAINS AS THIS OCCURS.
FOR SATURDAY AND SUNDAY...AS HIGH PRESSURE SLIPS OFF THE
SOUTHEASTERN NEW ENGLAND COAST SATURDAY MORNING, THE FLOW SHOULD
TURN FROM EAST-SOUTHEAST TO MORE SOUTHERLY. AS THIS OCCURS, SOME WAA
MAY ALLOW A LINGERING BOUNDARY TO OUR SOUTH TO LIFT BACK NORTH AS A
WARM FRONT. OVERALL WHILE SATURDAY LOOKS TO BE DRY, AN ISOLATED
SHOWER OR THUNDERSTORM CANNOT BE RULED OUT DURING PEAK HEATING
ESPECIALLY INLAND NORTH OF A POSSIBLE WARM FRONTAL FEATURE. AS THE
UPPER-LEVEL FLOW STARTS TO TURN MORE CYCLONIC SUNDAY, SOME SHOWERS
AND THUNDERSTORMS MAY DEVELOP ESPECIALLY INLAND IN THE AFTERNOON
PROBABLY TIED TO A LEE SIDE TROUGH. OVERALL, WE USED A 50/50 BLEND
OF CONTINUITY AND WPC GUIDANCE.
FOR MONDAY AND TUESDAY...A SIGNIFICANT UPPER-LEVEL TROUGH MAY SLIDE
ACROSS THE GREAT LAKES REGION. THIS WILL DRIVE LOW PRESSURE WELL TO
OUR NORTH, HOWEVER THE ASSOCIATED COLD FRONT WILL ARRIVE INTO OUR
AREA AROUND THE LATE MONDAY INTO TUESDAY TIME FRAME. THERE SHOULD BE
DECENT INSTABILITY AHEAD OF THIS FEATURE AS DEEPER MOISTURE ADVECTS
NORTHEASTWARD IN ADVANCE OF THE SURFACE FRONT, AND ALSO INCREASING
CYCLONIC FLOW. THIS COULD RESULT IN SOME STRONGER CONVECTIVE CELLS,
HOWEVER THE SEVERE WEATHER THREAT WILL DEPEND ON THE TIMING OF THE
LARGE SCALE FORCING AND ORGANIZATION AS WELL AS THE ACTUAL
INSTABILITY. AS OF NOW, MONDAY MAY HAVE A HIGHER CHC OF CONVECTION
ESPECIALLY ACROSS OUR WESTERN ZONES. WE KEPT CHC POPS AS A RESULT.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
MOSTLY VFR CONDITIONS ARE EXPECTED...WITH THE FOLLOWING EXCEPTIONS.
PATCHY BR RESULTING IN VISIBILITIES OF 2 TO 3 MILES IS STILL
EXPECTED TO DEVELOP THROUGH 12Z THIS MORNING. BY 18Z, COULD BEGIN TO
SEE ISOLATED TSRA DEVELOPMENT ACROSS THE REGION. THE HIGHEST CHANCES
FOR TSRA LOOK TO BE AT KABE, KRDG, KACY, AND KMIV...THOUGH EVEN AT
THESE LOCATIONS, CHANCE FOR DEVELOPMENT IS TOO LOW AND COVERAGE IS
EXPECTED TO BE TOO LIMITED TO INCLUDE IN THE TAFS AT THIS TIME.
EXPECT A WIND SHIFT TO NORTHWESTERLY WINDS AFTER 00Z TONIGHT,
BRINGING IN DRIER AIR AND DECREASING THE CHANCES FOR ANY MORE BR
DEVELOPMENT.
OUTLOOK...
THURSDAY AND FRIDAY...A FEW SHOWERS AND THUNDERSTORMS SHOULD BE
AROUND MAINLY THURSDAY WITH LOCALLY SUB-VFR CONDITIONS. OTHERWISE,
MAINLY VFR.
SATURDAY AND SUNDAY...SOME SHOWERS AND THUNDERSTORMS POSSIBLE
ESPECIALLY SUNDAY AFTERNOON AND EVENING, RESULTING IN BRIEF
SUB-VFR CONDITIONS.
&&
.MARINE...
THOUGH WINDS WILL CONTINUE TO SUBSIDE OVER THE NEXT FEW HOURS, HAVE
NOT MADE ANY CHANGES TO THE EXPIRATION TIME OF THE SCA ON THE OCEAN
WATERS AS SEAS AT BUOY 44009 REMAIN NEAR 6 FT AND WILL BE SLOW TO
DIMINISH. ONCE SEAS DO DIMINISH, EXPECT BOTH WINDS AND SEAS TO
REMAIN BELOW SCA CRITERIA THROUGH TONIGHT. HOWEVER, SOME
THUNDERSTORMS THIS AFTERNOON AND EVENING WILL BE CAPABLE OF STRONG
GUSTY WINDS.
OUTLOOK...
THURSDAY...A FRONTAL BOUNDARY LOOKS TO LINGER NEAR THE SOUTHERN
WATERS, HOWEVER SUB-ADVISORY CONDITIONS ARE ANTICIPATED.
FRIDAY AND SATURDAY...HIGH PRESSURE ARRIVES FRIDAY THEN SHIFTS OFF
THE SOUTHEASTERN NEW ENGLAND COAST FRIDAY NIGHT AND SATURDAY. THIS
MAY RESULT IN AN ONSHORE FLOW THAT STRENGTHENS SOME FOR A TIME
BEFORE TURNING MORE SOUTHERLY. IT APPEARS THOUGH THAT THE CONDITIONS
WILL REMAIN BELOW ADVISORY CRITERIA.
SUNDAY...A WARM FRONT MAY NEAR OUR SOUTHERN WATERS, HOWEVER THE FLOW
LOOKS WEAK ENOUGH TO KEEP CONDITIONS BELOW ADVISORY CRITERIA.
&&
.RIP CURRENTS...
THE THREAT FOR RIP CURRENTS ALONG THE ATLANTIC COAST IS MODERATE
TODAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
ANZ450>455.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...GORSE
AVIATION...GORSE/JOHNSON
MARINE...GORSE/JOHNSON
RIP CURRENTS...
...PREVIOUS EXTENDED FORECAST DISCUSSION...
THU-TUE...WEAK MID/UPR LVL WIND PATTERN CONTINUES ACRS THE SRN TIER
STATES WITH RUC ANALYSIS SHOWING WINDS SPEED AOB 30KTS. IN
FACT...OUTSIDE OF AN 80-100KT H30-H20 LIFTING JET EXTENDING FROM THE
MIDWEST INTO SRN QUEBEC...THERE IS LITTLE IN THE WAY OF SIG JET
ENERGY ACRS THE MAJORITY OF THE CONUS OR THE EPAC. THE TEPID NATURE
OF THE CURRENT JET PATTERN WILL ENSURE THE ATLC SUBTROPICAL
RIDGE...CURRENTLY EXTENDING FROM THE NW GOMEX AND INTO THE CENTRAL
ATLC VIA THE FL STRAITS...WILL REMAIN THE DOMINANT WX FEATURE FOR
CENTRAL FL THRU MID JULY.
THIS IS A TYPICAL MID SUMMER WX PATTERN...SO NO BIG SURPRISES IN
STORE THRU THE FIRST PART OF NEXT WEEK. BROAD TROFFING PATTERN OVER
THE ERN CONUS FED BY THE AFOREMENTIONED JET MAX WILL KEEP THE RIDGE
AXIS SUPPRESSED OVER THE S HALF OF FL THRU THU...GIVING THE EAST
CENTRAL PENINSULA ONE MORE DAY OF 40-60POPS. AS THE TROF DAMPENS AND
LIFT OUT TO THE N...THE ATLC RIDGE WILL DRIFT BACK INTO THE
CENTRAL/NRN PENINSULA WHERE IT WILL REMAIN INTO EARLY NEXT WEEK.
WITH THE RIDGE AXIS BUILDING OVERHEAD...THE H85-H50 STEERING FLOW
WILL BE QUITE WEAK...GENERALLY AOB 10KTS...WHILE ANY MEANINGFUL
MID/UPR LVL IMPULSES THAT MIGHT PUSH PRECIP CHANCES ABV THE 50PCT
MARK WILL BE BLOCKED OUT. WHILE WEAK FLOW WILL ALLOW BOTH SEA
BREEZES TO MAKE GOOD INLAND PENETRATION...THE RESULTING SLOW STORM
MOTION WILL FURTHER LIMIT OVERALL COVERAGE. POPS DIMINISHING TO AOB
40PCT ON FRI...THEN AOB 30PCT THRU THE WEEKEND.
GFS/ECMWF MODELS INDICATE THE NEXT SHORT WAVE TROF DVLPG OVER THE
ERN CONUS BY EARLY NEXT WEEK. THIS WILL SUPPRESS THE ATLC RIDGE AXIS
BACK INTO THE SRN PENINSULA AND ALLOW A W/SWRLY FLOW PATTERN TO
RDVLP ACRS CENTRAL FL...SHIFTING THE CONCENTRATION OF DIURNAL
PRECIP BACK TO THE EAST.
MAX/MIN TEMPS AT OR SLIGHTLY ABV AVG THRU THE PD...BUT NOT BY MORE
THAN 2-3F. AFTN READINGS IN THE U80S/L90S...MRNG READINGS IN THE
L/M70S.
&&
.AVIATION...SEA BREEZE STORMS INTO EARLY EVENING SPREADING INTO THE
INTERIOR WITH A FEW MOVING BACK TOWARDS THE COAST...MAINLY NORTH OF
KMLB. PATCHY GROUND FOG MAY REDUCE VSBYS SOUTH OF MCO (VRB/FPR/SUA)
AGAIN OVERNIGHT/EARLY WED MORNING THROUGH 13Z DUE TO VERY MOIST LOW
LEVELS AND CALM WIND. SEA BREEZE REGIME WITH SCT AFTN STORMS AGAIN
FOR THU.
&&
.MARINE...AFTERNOON-THU...SURFACE RIDGE AXIS SITUATED NEAR THE
CENTRAL FL PENINSULA WITH MAINLY WEAK PRESSURE GRADIENT. ONSHORE
FLOW AGAIN BECOMING SW/WSW THIS EVENING AND OVERNIGHT. SEA BREEZE TO
DEVELOP AGAIN EARLY THU AFTERNOON AND WILL MOVE SLOWLY INLAND WITH
WINDS ONCE AGAIN BACKING E/ESE NEAR THE COAST. THE MAIN MARINE
WEATHER CONCERN WILL CONTINUE TO BE STORMS THAT PRODUCE LIGHTNING
STRIKES AND GUSTY WINDS. THESE SHOULD OCCUR MAINLY DURING THE NIGHT
AND MORNING OVER THE OPEN ATLANTIC. DAYTIME HEATING STORMS OVER THE
MAINLAND SHOULD CONTINUE TO AFFECT THE INTRACOASTAL AND NEAR SHORE
ATLANTIC.
...PREVIOUS EXTENDED MARINE DISCUSSION...
FRI-SUN...WEAK SFC/BNDRY LYR PGRAD THRU THE UPCOMING WEEKEND AS THE
ATLC RIDGE AXIS LIFTS NWD FROM THE FL STRAITS INTO THE FL PANHANDLE.
FAVORABLE BOATING CONDITIONS WILL RESULT WITH A PREVAILING LIGHT TO
GENTLE SERLY BREEZE KEEPING SEAS AOB 2FT NEARSHORE AND 2-3FT
OFFSHORE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 74 90 76 88 / 30 40 20 40
MCO 75 92 75 91 / 30 50 30 50
MLB 74 88 75 88 / 20 50 20 30
VRB 72 89 74 88 / 20 50 20 30
LEE 76 92 76 91 / 30 50 30 50
SFB 76 93 76 92 / 30 50 30 50
ORL 76 93 76 92 / 30 50 30 50
FPR 73 88 73 87 / 20 50 20 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...SEDLOCK
RADAR/IMPACT WEATHER....VOLKMER
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
422 AM EDT WED JUL 9 2014
.DISCUSSION...
TODAY...LARGELY A PERSISTENCE FORECAST BUT SUBTLE DIFFERENCES
WILL PRODUCE CHANGES IN THE CONVECTIVE EVOLUTION TODAY COMPARED
TO YESTERDAY. THE LOW LEVEL RIDGE AXIS REMAINS ACROSS THE SOUTHERN
HALF OF FL PENINSULA WITH A LIGHT W TO NW FLOW EXPECTED THIS
MORNING BEFORE TURNING ONSHORE IN AN EASTERLY SEA BREEZE BY EARLY
AFTN. SUFFICIENT SOLAR HEATING WILL PRODUCE HIGH TEMPS IN THE
LOWER 90S INTERIOR AND NEAR 90 COAST. FORECAST MODEL SOUNDINGS DO
SHOW A LITTLE DRIER AIR ACROSS THE NORTHERN 1/3 OF FORECAST AREA.
THIS SHOULD REDUCE STORM COVERAGE SOMEWHAT. THE MORNING SHOULD BE
MOSTLY DRY THEN THE EAST COAST SEA BREEZE SHOULD SPARK ISOLD/SCT
STORMS NEAR THE COAST ESP SOUTH OF THE CAPE THIS AFTN...SHIFTING
TO THE INTERIOR LATER IN THE DAY. BOUNDARY COLLISIONS SHOULD AGAIN
PRODUCE A FEW STRONG STORMS MAINLY INTERIOR LATE THIS AFTN AND
PERSIST INTO THE EARLY EVE. THE BEST CHANCE FOR PUSH BACK TO THE
COAST LATE IN THE DAY/EVE WILL BE NORTH OF THE CAPE.
THU-TUE...
WEAK MID/UPR LVL WIND PATTERN CONTINUES ACRS THE SRN TIER STATES
WITH RUC ANALYSIS SHOWING WINDS SPEED AOB 30KTS. IN FACT...OUTSIDE
OF AN 80-100KT H30-H20 LIFTING JET EXTENDING FROM THE MIDWEST INTO
SRN QUEBEC...THERE IS LITTLE IN THE WAY OF SIG JET ENERGY ACRS THE
MAJORITY OF THE CONUS OR THE EPAC. THE TEPID NATURE OF THE CURRENT
JET PATTERN WILL ENSURE THE ATLC SUBTROPICAL RIDGE...CURRENTLY
EXTENDING FROM THE NW GOMEX AND INTO THE CENTRAL ATLC VIA THE FL
STRAITS...WILL REMAIN THE DOMINANT WX FEATURE FOR CENTRAL FL THRU
MID JULY.
THIS IS A TYPICAL MID SUMMER WX PATTERN...SO NO BIG SURPRISES IN
STORE THRU THE FIRST PART OF NEXT WEEK. BROAD TROFFING PATTERN OVER
THE ERN CONUS FED BY THE AFOREMENTIONED JET MAX WILL KEEP THE RIDGE
AXIS SUPPRESSED OVER THE S HALF OF FL THRU THU...GIVING THE EAST
CENTRAL PENINSULA ONE MORE DAY OF 40-60POPS. AS THE TROF DAMPENS AND
LIFT OUT TO THE N...THE ATLC RIDGE WILL DRIFT BACK INTO THE
CENTRAL/NRN PENINSULA WHERE IT WILL REMAIN INTO EARLY NEXT WEEK.
WITH THE RIDGE AXIS BUILDING OVERHEAD...THE H85-H50 STEERING FLOW
WILL BE QUITE WEAK...GENERALLY AOB 10KTS...WHILE ANY MEANINGFUL
MID/UPR LVL IMPULSES THAT MIGHT PUSH PRECIP CHANCES ABV THE 50PCT
MARK WILL BE BLOCKED OUT. WHILE WEAK FLOW WILL ALLOW BOTH SEA
BREEZES TO MAKE GOOD INLAND PENETRATION...THE RESULTING SLOW STORM
MOTION WILL FURTHER LIMIT OVERALL COVERAGE. POPS DIMINISHING TO AOB
40PCT ON FRI...THEN AOB 30PCT THRU THE WEEKEND.
GFS/ECWMF MODELS INDICATE THE NEXT SHORT WAVE TROF DVLPG OVER THE
ERN CONUS BY EARLY NEXT WEEK. THIS WILL SUPPRESS THE ATLC RIDGE AXIS
BACK INTO THE SRN PENINSULA AND ALLOW A W/SWRLY FLOW PATTERN TO
RDVLP ACRS CENTRAL FL...SHIFTING THE CONCENTRATION OF DIURNAL
PRECIP BACK TO THE EAST.
MAX/MIN TEMPS AT OR SLIGHTLY ABV AVG THRU THE PD...BUT NOT BY MORE
THAN 2-3F. AFTN READINGS IN THE U80S/L90S...MRNG READINGS IN THE
L/M70S.
&&
.AVIATION...
PATCHY GROUND FOG MAY REDUCE VSBYS ACROSS SOUTHERN TERMINALS
(VRB/FPR/SUA) THROUGH 12Z IN VERY MOIST LOW LEVELS AND CALM
WIND. SEA BREEZE SHOULD SPARK ISOLD/SCT TSRA 17Z-19Z NEAR THE
COAST THEN SPREAD INLAND. HIGHEST COVERAGE LOOKS TO BE OVER THE
INTERIOR 21Z-24Z WITH SOME PUSH BACK TO THE COAST NORTH OF THE
CAPE POSSIBLE THIS EVENING.
&&
.MARINE...
TODAY...FAVORABLE BOATING CONDITIONS WILL CONTINUE WITH SURFACE
RIDGE IN THE VICINITY AND ASSOCIATED WEAK PRESSURE GRADIENT.
LIGHT OFFSHORE FLOW THIS MORNING WILL TURN ONSHORE NEAR THE COAST
NEAR 10 KNOTS BEHIND THE SEA BREEZE. OTHERWISE VARIABLE WINDS
LESS THAN 10 KTS OFFSHORE. WINDS WILL RETURN TO A SYNOPTIC S/SW
FLOW THIS EVENING/OVERNIGHT AS THE SEA BREEZE CIRCULATION
DIMINISHES. MAIN MARINE WEATHER CONCERNS CONTINUE TO BE STORMS
THAT PRODUCE LIGHTNING STRIKES AND GUSTY WINDS. THESE SHOULD OCCUR
MAINLY DURING THE NIGHT AND MORNING OVER THE OPEN ATLANTIC.
DAYTIME HEATING STORMS OVER THE MAINLAND SHOULD CONTINUE TO AFFECT
THE INTRACOASTAL AND NEAR SHORE ATLANTIC.
THU-SUN...
WEAK SFC/BNDRY LYR PGRAD THRU THE UPCOMING WEEKEND AS THE ATLC RIDGE
AXIS LIFTS NWD FROM THE FL STRAITS INTO THE FL PANHANDLE. FAVORABLE
BOATING CONDITIONS WILL RESULT WITH A PREVAILING LIGHT TO GENTLE
SERLY BREEZE KEEPING SEAS AOB 2FT NEARSHORE AND 2-3FT OFFSHORE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 91 74 92 76 / 30 30 40 20
MCO 93 75 94 75 / 50 30 40 30
MLB 89 74 90 75 / 40 20 50 20
VRB 90 72 91 74 / 40 20 50 20
LEE 93 76 94 77 / 40 30 40 30
SFB 93 76 95 77 / 40 30 40 30
ORL 93 77 95 77 / 50 30 40 30
FPR 90 73 90 73 / 40 20 50 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...KELLY
LONG TERM....BRAGAW
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
655 PM EDT WED JUL 9 2014
.UPDATE...
SCATTERED THUNDERSTORMS WILL OCCUR MAINLY OVER CENTRAL GA ALONG AND
SOUTH OF A WEAK FRONTAL BOUNDARY FROM FRANKLIN THROUGH CONYERS TO
ATHENS THIS EVENING. AN UPPER LEVEL DISTURBANCE CONTINUES TO TRIGGER
ADDITIONAL SCATTERED THUNDERSTORMS OVER EXTREME NORTH GA FROM TRENTON
TO DALTON. THE STORMS WILL GENERALLY MOVE EAST AT 15 KTS BEFORE
DISSIPATING BY MIDNIGHT. THE POPS OVER THE ATLANTA METRO AREA HAVE
BEEN LOWERED INTO THE 30-40 PERCENT RANGE AND ALL OF NORTH GA WILL
DROP TO AROUND 20 PERCENT AFTER MIDNIGHT.
16/39
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
COLD FRONT IS PUSHING INTO NORTHWEST GEORGIA AT AFD TIME...WITH A
LINE OF CONVECTION ROUGHLY FROM ATHENS TO THE SOUTH SIDE OF ATLANTA
ALONG A WEAK SURFACE CONVERGENCE ZONE AND DIFFERENTIAL HEATING
BOUNDARY /FROM MIDLEVEL CLOUDS UP NORTH/. DEEP UPPER TROUGH REMAINS
IN PLACE OVER THE EASTERN PORTION OF THE COUNTRY BUT WILL BEGIN TO
LIFT TOWARD THE END OF THE SHORT TERM...WITH THE FRONT PROGGED TO
LINGER ACROSS CENTRAL GEORGIA THROUGH THURSDAY.
CONCERN FOR THIS EVENING WILL BE MAINLY ABOUT CONVECTION...NAMELY
COVERAGE AND INTENSITY. EXPECT CHANCES TO REMAIN PRETTY HIGH AS DEEP
LAYER MOISTURE HAS INCREASED AHEAD OF THE FRONT. BUFR SOUNDINGS
REMAIN FAIRLY SATURATED THROUGH THE EVENING AND OVERNIGHT HOURS AND
WITH PLENTIFUL SBCAPE...IT IS MAINLY JUST A MATTER OF WHERE
CONVECTION WILL BE ABLE TO GET GOING. CANNOT RULE OUT ISOLATED
SEVERE STORMS WITH MARGINALLY SEVERE HAIL AS THE MAIN THREAT. DCAPE
VALUES ARE BETWEEN 1000-1300 J/KG ACROSS NORTH GEORGIA AND ALSO
ACROSS PORTIONS OF CENTRAL GEORGIA...WITH AREAS FROM METRO ATLANTA
TO ATHENS TOO LOW FOR MUCH CONCERN. NEW TRENDS IN RAP DATA KEEP THE
HIGH DCAPE VALUES IN PLACE DOWN SOUTH BUT DIMINISH THEM UP NORTH
THROUGH THE AFTERNOON...SO BEST CHANCE FOR MARGINAL SEVERE WOULD
LIKELY BE ACROSS PORTIONS OF CENTRAL GEORGIA.
WIDESPREAD CLOUD COVER AND PLENTIFUL SURFACE MOISTURE WILL KEEP HIGH
TEMPS TOMORROW A FEW DEGREES LOWER THAN NORMAL...WITH NEAR-NORMAL
LOWS.
TDP
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LONG WAVE TROUGH TO CONTINUE TO FILL OVER ERN CONUS FRI THRU SUN
WHILE E-W ORIENTED RIDGE ALOFT BUILDS OVER SRN STATES. SHOULD SEE
WARMING TEMPS AND LOWER POPS IN THIS PATTERN. ISOLD SHRA/TSRA
STILL LIKELY BUT LESS COVERAGE THAN PREVIOUS DAYS. LARGE UPPER
VORTEX AND TROUGH PROGGED BY 12Z MED RANGE MODELS TO SWING SOUTH
FROM CANADA INTO ERN CONUS AGAIN MONDAY WITH PERIPHERY OF
WESTERLIES AND WEAK FRONT DIPPING INTO GA ON TUES. EXPECT RETURN
TO HIGHER POPS AND SLIGHTLY COOLER TEMP TUES/WED. MADE ONLY
SMALL MODIFICATIONS TO POPS/WX AND TEMPS WITH MODEST ADJUSTMENTS
TOWARD HPC GUIDANCE.
SNELSON
PREV LONG TERM DISCUSSION... /ISSUED 148 PM EDT WED JUL 9 2014/
/VALID THURSDAY NIGHT THROUGH TUESDAY/...
THURSDAY AND FRIDAY....EXTENDED PERIOD BEGINS WITH EASTERN US TROF
CENTERED NEAR 85 WEST AND REMNANT FRONTAL BOUNDARY DRAPED ACROSS
CENTRAL GA. BOTH THE ECMWF AND GFS IN GOOD AGREEMENT WITH BOTH THE
LOCATION OF THE FRONT AND DEPTH OF THE EASTERN TROF. END RESULT IS
MOSTLY DIURNAL CONVECTION PARTICULARLY NEAR THE BOUNDARY ALONG AND
SOUTH OF I85 WITH BEST CHANCES ON THURSDAY. MODEL CAPE VALUES ARE
MODEST AND TYPICAL FOR SUMMERTIME PATTERN...HOWEVER PRECIPITABLE
WATER VALUES PEAK ACROSS THE AREA ON THURSDAY BETWEEN 1.8 AND 2.0
INCHES WHICH COULD RESULT IN SOME EFFICIENT RAIN PRODUCING STORMS.
DRIER AIR WORKS IN BEHIND THE FRONT ON FRIDAY SQUASHING THE BEST
RAIN CHANCES TO THE SOUTH AND EAST PORTION OF THE AREA...I.E. CSG
TO MCN AND POINTS SOUTH NEAR THE REMNANT FRONT.
WEEKEND...THE GENERAL PATTERN PERSISTS INTO THE WEEKEND ACROSS THE
EASTERN U.S. WITH THE TROF AXIS SHIFTING SLIGHTLY EAST OF GA
BY SATURDAY AND SOME MID LEVEL RIDGING TRYING TO NOSE IN FROM THE
WEST...WHILE THE REMNANT FRONT IS ALL BUT A DISTANT MEMORY. END
RESULT WILL BE NEAR TO SLIGHTLY BELOW CLIMO POP CHANCES BOTH
SATURDAY AND SUNDAY. CAVEAT HERE IS THAT PW VALUES SOAR UP TO NEAR
OR SLIGHTLY ABOVE 2.0 INCHES MAKING FOR A MUGGY WEEKEND. STILL
THINK THE GREATEST CHANCES WILL BE SOUTH AND EAST CLOSER TO WHERE
SEA BREEZE ACTIVITY HAS THE BEST INFLUENCES LATE IN THE AFTERNOON.
MONDAY AND TUESDAY...GFS AND ECMWF SLIGHTLY DIFFERENT BUT STILL
GENERALLY AGREE THAT THE LARGER SCALE TROF WILL BE REINFORCED
ACROSS THE REGION WITH ANOTHER FRONT APPROACHING. END RESULT WILL
BE INCREASED POP CHANCES ON MONDAY AND PARTICULARLY TUESDAY. MUCH
CAN HAPPEN BETWEEN NOW AND THEN SO WILL TREND HIGHER BUT NOT GO
OVERBOARD.
STELLMAN
&&
AVIATION...
18Z UPDATE...
VFR CONDITION THIS AFTERNOON WITH CONVECTION STARTING TO FIRE.
HAVE GONE PREVAILING SHRA EVERYWHERE WITH TEMPO TSRA STARTING 20Z
AND WILL REFINE AS NECESSARY. CONVECTION MAY LINGER OVERNIGHT SO
ADDED VCSH THROUGH 06Z. EXPECT MVFR CIGS TO DEVELOP OVERNIGHT...
LIFTING ON THURSDAY WITH ADDITIONAL CONVECTION POSSIBLE SO
INTRODUCED PROB30 STARTING AT 15Z. WINDS GENERALLY W THROUGH THE
PERIOD WITH LOW-END GUSTS THIS AFTERNOON.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON TIMING OF CONVECTION THIS AFTERNOON AND CIGS TONIGHT.
HIGH ON ALL OTHER ELEMENTS.
TDP
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 70 89 69 91 / 60 50 30 30
ATLANTA 71 86 71 89 / 60 40 30 20
BLAIRSVILLE 64 82 63 84 / 60 30 20 20
CARTERSVILLE 68 86 67 89 / 60 30 20 20
COLUMBUS 73 90 73 92 / 50 60 30 30
GAINESVILLE 70 85 69 88 / 60 40 30 20
MACON 71 90 70 91 / 40 60 40 30
ROME 69 87 67 90 / 60 30 20 10
PEACHTREE CITY 69 87 68 89 / 60 40 30 20
VIDALIA 73 92 73 90 / 20 60 50 60
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TDP
LONG TERM....SNELSON
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
348 PM EDT WED JUL 9 2014
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
COLD FRONT IS PUSHING INTO NORTHWEST GEORGIA AT AFD TIME...WITH A
LINE OF CONVECTION ROUGHLY FROM ATHENS TO THE SOUTH SIDE OF ATLANTA
ALONG A WEAK SURFACE CONVERGENCE ZONE AND DIFFERENTIAL HEATING
BOUNDARY /FROM MIDLEVEL CLOUDS UP NORTH/. DEEP UPPER TROUGH REMAINS
IN PLACE OVER THE EASTERN PORTION OF THE COUNTRY BUT WILL BEGIN TO
LIFT TOWARD THE END OF THE SHORT TERM...WITH THE FRONT PROGGED TO
LINGER ACROSS CENTRAL GEORGIA THROUGH THURSDAY.
CONCERN FOR THIS EVENING WILL BE MAINLY ABOUT CONVECTION...NAMELY
COVERAGE AND INTENSITY. EXPECT CHANCES TO REMAIN PRETTY HIGH AS DEEP
LAYER MOISTURE HAS INCREASED AHEAD OF THE FRONT. BUFR SOUNDINGS
REMAIN FAIRLY SATURATED THROUGH THE EVENING AND OVERNIGHT HOURS AND
WITH PLENTIFUL SBCAPE...IT IS MAINLY JUST A MATTER OF WHERE
CONVECTION WILL BE ABLE TO GET GOING. CANNOT RULE OUT ISOLATED
SEVERE STORMS WITH MARGINALLY SEVERE HAIL AS THE MAIN THREAT. DCAPE
VALUES ARE BETWEEN 1000-1300 J/KG ACROSS NORTH GEORGIA AND ALSO
ACROSS PORTIONS OF CENTRAL GEORGIA...WITH AREAS FROM METRO ATLANTA
TO ATHENS TOO LOW FOR MUCH CONCERN. NEW TRENDS IN RAP DATA KEEP THE
HIGH DCAPE VALUES IN PLACE DOWN SOUTH BUT DIMINISH THEM UP NORTH
THROUGH THE AFTERNOON...SO BEST CHANCE FOR MARGINAL SEVERE WOULD
LIKELY BE ACROSS PORTIONS OF CENTRAL GEORGIA.
WIDESPREAD CLOUD COVER AND PLENTIFUL SURFACE MOISTURE WILL KEEP HIGH
TEMPS TOMORROW A FEW DEGREES LOWER THAN NORMAL...WITH NEAR-NORMAL
LOWS.
TDP
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LONG WAVE TROUGH TO CONTINUE TO FILL OVER ERN CONUS FRI THRU SUN
WHILE E-W ORIENTED RIDGE ALOFT BUILDS OVER SRN STATES. SHOULD SEE
WARMING TEMPS AND LOWER POPS IN THIS PATTERN. ISOLD SHRA/TSRA
STILL LIKELY BUT LESS COVERAGE THAN PREVIOUS DAYS. LARGE UPPER
VORTEX AND TROUGH PROGGED BY 12Z MED RANGE MODELS TO SWING SOUTH
FROM CANADA INTO ERN CONUS AGAIN MONDAY WITH PERIPHERY OF
WESTERLIES AND WEAK FRONT DIPPING INTO GA ON TUES. EXPECT RETURN
TO HIGHER POPS AND SLIGHTLY COOLER TEMP TUES/WED. MADE ONLY
SMALL MODIFICATIONS TO POPS/WX AND TEMPS WITH MODEST ADJUSTMENTS
TOWARD HPC GUIDANCE.
SNELSON
PREV LONG TERM DISCUSSION... /ISSUED 148 PM EDT WED JUL 9 2014/
/VALID THURSDAY NIGHT THROUGH TUESDAY/...
THURSDAY AND FRIDAY....EXTENDED PERIOD BEGINS WITH EASTERN US TROF
CENTERED NEAR 85 WEST AND REMNANT FRONTAL BOUNDARY DRAPED ACROSS
CENTRAL GA. BOTH THE ECMWF AND GFS IN GOOD AGREEMENT WITH BOTH THE
LOCATION OF THE FRONT AND DEPTH OF THE EASTERN TROF. END RESULT IS
MOSTLY DIURNAL CONVECTION PARTICULARLY NEAR THE BOUNDARY ALONG AND
SOUTH OF I85 WITH BEST CHANCES ON THURSDAY. MODEL CAPE VALUES ARE
MODEST AND TYPICAL FOR SUMMERTIME PATTERN...HOWEVER PRECIPITABLE
WATER VALUES PEAK ACROSS THE AREA ON THURSDAY BETWEEN 1.8 AND 2.0
INCHES WHICH COULD RESULT IN SOME EFFICIENT RAIN PRODUCING STORMS.
DRIER AIR WORKS IN BEHIND THE FRONT ON FRIDAY SQUASHING THE BEST
RAIN CHANCES TO THE SOUTH AND EAST PORTION OF THE AREA...I.E. CSG
TO MCN AND POINTS SOUTH NEAR THE REMNANT FRONT.
WEEKEND...THE GENERAL PATTERN PERSISTS INTO THE WEEKEND ACROSS THE
EASTERN U.S. WITH THE TROF AXIS SHIFTING SLIGHTLY EAST OF GA
BY SATURDAY AND SOME MID LEVEL RIDGING TRYING TO NOSE IN FROM THE
WEST...WHILE THE REMNANT FRONT IS ALL BUT A DISTANT MEMORY. END
RESULT WILL BE NEAR TO SLIGHTLY BELOW CLIMO POP CHANCES BOTH
SATURDAY AND SUNDAY. CAVEAT HERE IS THAT PW VALUES SOAR UP TO NEAR
OR SLIGHTLY ABOVE 2.0 INCHES MAKING FOR A MUGGY WEEKEND. STILL
THINK THE GREATEST CHANCES WILL BE SOUTH AND EAST CLOSER TO WHERE
SEA BREEZE ACTIVITY HAS THE BEST INFLUENCES LATE IN THE AFTERNOON.
MONDAY AND TUESDAY...GFS AND ECMWF SLIGHTLY DIFFERENT BUT STILL
GENERALLY AGREE THAT THE LARGER SCALE TROF WILL BE REINFORCED
ACROSS THE REGION WITH ANOTHER FRONT APPROACHING. END RESULT WILL
BE INCREASED POP CHANCES ON MONDAY AND PARTICULARLY TUESDAY. MUCH
CAN HAPPEN BETWEEN NOW AND THEN SO WILL TREND HIGHER BUT NOT GO
OVERBOARD.
STELLMAN
&&
AVIATION...
18Z UPDATE...
VFR CONDITION THIS AFTERNOON WITH CONVECTION STARTING TO FIRE.
HAVE GONE PREVAILING SHRA EVERYWHERE WITH TEMPO TSRA STARTING 20Z
AND WILL REFINE AS NECESSARY. CONVECTION MAY LINGER OVERNIGHT SO
ADDED VCSH THROUGH 06Z. EXPECT MVFR CIGS TO DEVELOP OVERNIGHT...
LIFTING ON THURSDAY WITH ADDITIONAL CONVECTION POSSIBLE SO
INTRODUCED PROB30 STARTING AT 15Z. WINDS GENERALLY W THROUGH THE
PERIOD WITH LOW-END GUSTS THIS AFTERNOON.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON TIMING OF CONVECTION THIS AFTERNOON AND CIGS TONIGHT.
HIGH ON ALL OTHER ELEMENTS.
TDP
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 70 89 69 91 / 60 50 30 30
ATLANTA 71 86 71 89 / 60 40 30 20
BLAIRSVILLE 64 82 63 84 / 60 30 20 20
CARTERSVILLE 68 86 67 89 / 60 30 20 20
COLUMBUS 73 90 73 92 / 50 60 30 30
GAINESVILLE 70 85 69 88 / 60 40 30 20
MACON 71 90 70 91 / 40 60 40 30
ROME 69 87 67 90 / 60 30 20 10
PEACHTREE CITY 69 87 68 89 / 60 40 30 20
VIDALIA 73 92 73 90 / 20 60 50 60
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TDP
LONG TERM....SNELSON
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
112 PM EDT WED JUL 9 2014
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL EXTEND TOWARD THE COASTLINE FOR MUCH
OF THE PERIOD...WHILE A TROUGH OF LOW PRESSURE REMAINS INLAND. A
WEAK COLD FRONT WILL STALL OVER OR CLOSE TO THE REGION THURSDAY
AND WILL DISSIPATE BY THE WEEKEND. ANOTHER COLD FRONT COULD
APPROACH FROM THE WEST BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY THIS AFTERNOON...ONGOING FORECAST LOOKED TO BE IN GOOD SHAPE
SO ONLY MINOR TWEAKS TO THE HOURLY T/TD TRENDS WERE NEEDED.
PREVIOUS DISCUSSION FOLLOWS.
SURFACE HIGH PRESSURE WILL REMAIN CENTERED OFFSHORE TODAY...WITH
A TROUGH OF LOW PRESSURE SITUATED INLAND. 12Z KCHS RAOB SHOWED
QUITE DRY AIR THROUGHOUT THE COLUMN FOR THIS TIME OF YEAR WITH 1.3
PWATS...AS WELL AS SOME CAPPING NOTED ALOFT. GIVEN
THIS...SHOWER/THUNDERSTORM DEVELOPMENT MAY GO OFF A BIT LATER
TODAY. HI RES MODELS SUCH AS THE NSSL WRF AND HRRR INDICATE THAT
SOME ISOLATED ACTIVITY MAY FIRE OFF THE SEA BREEZE INITIALLY...THEN
LATER THIS AFTERNOON/EARLY EVENING THE FOCUS WILL SHIFT TO OUR
INLAND ZONES. MODELS HINT THAT CONVECTION WILL FIRE OFF THE INLAND
SURFACE TROUGH AND THEN WILL LIKELY BEGIN MOVE INTO OUR AREA.
COULD NOT RULE OUT A COUPLE STRONGER TO SEVERE STORMS ESPECIALLY
WHERE BOUNDARY INTERACTIONS OCCUR...HOWEVER WIDESPREAD SEVERE
WEATHER IS UNLIKELY GIVEN LACK OF DEEP LAYER SHEAR AND SIGNIFICANT
FORCING.
IT WILL BE ANOTHER HOT DAY...WITH 1000-850 MB THICKNESS VALUES
SUPPORTING HIGH TEMPS MOSTLY IN THE MID 90S AWAY FROM THE
IMMEDIATE COAST. THIS COMBINED WITH DEW POINTS IN THE LOW 70S
WILL YIELD HEAT INDICES UP TO AROUND 105 DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
ONGOING CONVECTION/ASSOCIATED OUTFLOW ORIGINATING NEAR THE INLAND
SURFACE TROUGH COULD BECOME ORGANIZED AND COULD PUSH BACK TOWARD THE
E/SE AND INTO THE FORECAST AREA THIS EVENING. FURTHER...THIS
CONVECTION COULD INTERACT WITH THE SEA BREEZE AND COULD PRODUCE
ISOLATED PULSE SEVERE WEATHER WITH DAMAGING WET MICROBURSTS MAINLY
INLAND THIS EVENING. THUS...POPS ARE ACTUALLY HIGHER AFTER 6 PM THAN
AT ANY TIME DURING THE DAY...ESPECIALLY INLAND. AFTER DARK...THE
SCENARIO BECOMES SOMEWHAT UNCERTAIN AND WILL DEPEND GREATLY ON THE
EVOLUTION OF THE EVENING CONVECTIVE REGIME. IN GENERAL...THE
FORECAST TAPERS POPS TO SLIGHT CHANCE ALL AREAS OVERNIGHT DUE TO
THE USUAL INFLUENCE OF DIURNAL STABILIZATION. EXCEPT WHERE RAIN
OCCURS...LOWS IN THE MID TO UPPER 70S WILL ONCE AGAIN PREVAIL MOST
AREAS TONIGHT.
THURSDAY AND FRIDAY...THE PATTERN AT THE SURFACE AND ALOFT WILL
BECOME MORE UNSETTLED FOR THE LATE WEEK PERIOD. DEEP LAYER RIDGING
WILL RETREAT FARTHER INTO THE ATLANTIC...AS AN AMPLIFYING UPPER
TROUGH SHIFTS OVER THE EAST COAST. SHORTWAVE ENERGY MOVING
DOWNSTREAM OF THE UPPER TROUGH AXIS WILL ALLOW THE INLAND SURFACE
TROUGH TO STRENGTHEN. A WEAK STATIONARY FRONT WILL LINGER OVER OR
JUST TO THE WEST OF THE FORECAST AREA THURSDAY...BEFORE
DISSIPATING NEAR THE COASTLINE FRIDAY. DEEP MOISTURE PROFILES WILL
DEEPEN WITHIN IMPROVED UPPER AND LOWER LEVEL FORCING...EVIDENT BY
PRECIPITABLE WATER VALUES RISING TO 2 INCHES LATE THURSDAY THROUGH
FRIDAY. HIGHER MOISTURE LEVELS AND SYNOPTIC SCALE FEATURES
ENHANCING TYPICAL SEABREEZE CONVECTION RAISES CONFIDENCE IN THE
DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS/THUNDERSTORMS. RAIN
CHANCES WILL PEAK IN THE 50 PERCENT RANGE EACH
AFTERNOON...DIMINISHING TO THE 20 TO 30 PERCENT RANGE DURING THE
OVERNIGHT HOURS WHEN BEST RAIN CHANCES TRANSITION TO THE MARINE
ZONES. HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN EARLIER IN
THE WEEK DUE TO LOWERING HEIGHTS ALOFT...THICKER CLOUDS AND BETTER
RAIN COVERAGE. EXPECT TEMPERATURES TO PEAK IN THE LOW TO MID 90S
AWAY FROM THE LOCALLY COOLER COASTLINE.
SATURDAY...UPPER RIDGING CENTERED OVER THE SOUTHERN PLAINS WILL
PRESS EASTWARD OVER THE WEEKEND...POSSIBLY DAMPENING THE EAST
COAST TROUGH. THERE IS SOME DISAGREEMENT BETWEEN MODEL SOLUTIONS
REGARDING THE EXTENT THE TROUGH LIFTS TO THE NORTH...WITH
DIFFERENCES IN CONVECTIVE POTENTIAL AS A RESULT. HOWEVER...BOTH
SOLUTIONS INDICATE THE INLAND SURFACE TROUGH PREVAILING AND
PRECIPITABLE WATER VALUES REMAINING NEAR 2 INCHES. WILL THUS LEAN
TOWARD SOLID THUNDERSTORM COVERAGE ONCE AGAIN...HIGHEST ALONG AND
INLAND OF THE SEABREEZE DURING THE AFTERNOON HOURS. HIGH
TEMPERATURES WILL REACH THE LOW TO MID 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
THE SOUTHEAST COAST WILL GENERALLY REMAIN BETWEEN A BROAD UPPER
TROUGH TO THE NORTH AND STRONG RIDGING JUST TO THE SOUTH INTO
EARLY NEXT WEEK. THE INLAND SURFACE TROUGH WILL BE FAIRLY WEAK ON
SUNDAY...THEN STEADILY STRENGTHEN MONDAY AND TUESDAY AHEAD OF AN
APPROACHING COLD FRONT FROM THE WEST ON WEDNESDAY. DEEP MOISTURE
CONTINUES TO BE QUITE HIGH THROUGH THE EXTENDED FORECAST
PERIOD...SUPPORTING AT LEAST SCATTERED THUNDERSTORM COVERAGE EACH
AFTERNOON AS TYPICAL SEABREEZE CONVECTION IS ENHANCED BY THE
SYNOPTIC SCALE FORCING. WILL ADVERTISE THUNDERSTORM CHANCES IN THE
30 TO NEAR 40 PERCENT RANGE DURING THE DAYTIME HOURS...DIMINISHING
OVER LAND AREAS EACH EVENING/NIGHT. HIGH TEMPERATURES WILL VARY
LITTLE THROUGH EARLY TO MID WEEK...REACHING THE LOW TO MID 90S
AWAY FROM THE LOCALLY COOLER COASTLINE.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
VFR IS EXPECTED TO BE THE RULE THROUGH MUCH OF THE VALID TAF
PERIOD. SHOWERS/THUNDERSTORMS WILL BE POSSIBLE THIS
AFTERNOON/EARLY EVENING...HOWEVER THE CHANCES OF A DIRECT IMPACT
AT EITHER TERMINAL IS TOO LOW TO INCLUDE MENTION IN THE TAF AT
THIS TIME. WILL CONTINUE TO MONITOR AND WILL AMEND AS NEEDED BASED
ON LATEST RADAR TRENDS. CONVECTION IS POSSIBLE AGAIN ON
THURSDAY...HOWEVER MOST ACTIVITY SHOULD BE AFTER 18Z.
EXTENDED AVIATION OUTLOOK...THERE WILL BE INCREASING CHANCES FOR
BRIEF FLIGHT RESTRICTIONS IN SHOWERS/THUNDERSTORMS BY THURSDAY
AFTERNOON...CONTINUING INTO SATURDAY...AS DEEP LAYER MOISTURE
INCREASES CONVECTIVE COVERAGE WITHIN A BROAD UPPER LEVEL TROUGH
OVER THE EASTERN UNITED STATES.
&&
.MARINE...
W/SW WINDS 10-15 KT THIS MORNING...AS HIGH AS 15-20 KT BEYOND 20 NM...
WILL GIVE WAY TO A VIGOROUS SEA BREEZE CIRCULATION PRODUCING
ONSHORE WINDS AS HIGH AS 15-20 KT ESPECIALLY WITHIN NEARSHORE
WATERS THIS AFTERNOON/EVENING. TONIGHT...S/SW WINDS AS HIGH AS
15-20 KT WILL PREVAIL. SEAS WILL AVERAGE 3-4 FT MOST AREAS. BEYOND
20 NM...SEAS AS HIGH AS 5 FT WILL OCCUR THIS MORNING AND COULD
OCCUR AGAIN TONIGHT.
THURSDAY THROUGH SUNDAY...THE ATLANTIC RIDGE WILL SHIFT FARTHER
OUT TO SEA BY THE LATE WEEK PERIOD...AS A BROAD TROUGH OF LOW
PRESSURE BUILDS OVER THE EAST AND SOUTHEAST UNITED STATES. THIS
PATTERN CHANGE WILL RESULT IN MORE SOLID SOUTHERLY WINDS AND
INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS. NOCTURNAL SURGES
UP TO 15 TO 20 KT ARE POSSIBLE EACH NIGHT...HOWEVER CONDITIONS ARE
STILL EXPECTED TO REMAIN BELOW ADVISORY CONDITIONS OUTSIDE OF
THUNDERSTORMS.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...ECT
SHORT TERM...SPR/WMS
LONG TERM...WMS
AVIATION...ECT/SPR
MARINE...ECT/WMS
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1042 AM EDT WED JUL 9 2014
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL EXTEND TOWARD THE COASTLINE FOR MUCH
OF THE PERIOD...WHILE A TROUGH OF LOW PRESSURE REMAINS INLAND. A
WEAK COLD FRONT WILL STALL OVER OR CLOSE TO THE REGION THURSDAY
AND WILL DISSIPATE BY THE WEEKEND. ANOTHER COLD FRONT COULD
APPROACH FROM THE WEST BY THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH PRESSURE WILL REMAIN CENTERED OFFSHORE TODAY...WITH A
TROUGH OF LOW PRESSURE SITUATED INLAND. 12Z KCHS RAOB SHOWED
QUITE DRY AIR THROUGHOUT THE COLUMN FOR THIS TIME OF YEAR WITH 1.3
PWATS...AS WELL AS SOME CAPPING NOTED ALOFT. GIVEN
THIS...SHOWER/THUNDERSTORM DEVELOPMENT MAY GO OFF A BIT LATER
TODAY. HI RES MODELS SUCH AS THE NSSL WRF AND HRRR INDICATE THAT
SOME ACTIVITY MAY FIRE OFF THE SEA BREEZE THIS AFTERNOON
INITIALLY...THEN LATE THIS AFTERNOON/EARLY EVENING THE FOCUS WILL
SHIFT TO OUR INLAND ZONES. MODELS HINT THAT CONVECTION WILL FIRE OFF
THE INLAND SURFACE TROUGH AND THEN WILL LIKELY BEGIN MOVE INTO OUR
AREA. COULD NOT RULE OUT A COUPLE STRONGER TO SEVERE STORMS
ESPECIALLY WHERE BOUNDARY INTERACTIONS OCCUR...HOWEVER WIDESPREAD
SEVERE WEATHER IS UNLIKELY GIVEN LACK OF DEEP LAYER SHEAR AND
SIGNIFICANT FORCING.
IT WILL BE ANOTHER HOT DAY...WITH 1000-850 MB THICKNESS VALUES
SUPPORTING HIGH TEMPS MOSTLY IN THE MID 90S AWAY FROM THE
IMMEDIATE COAST. THIS COMBINED WITH DEW POINTS IN THE LOW 70S
WILL YIELD HEAT INDICES UP TO AROUND 105 DEGREES.
OVERALL...ONGOING FORECAST WAS ON TRACK SO ONLY MINOR TWEAKS TO
THE HOURLY T/TD GRIDS WERE NEEDED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
ONGOING CONVECTION/ASSOCIATED OUTFLOW ORIGINATING NEAR THE INLAND
SURFACE TROUGH COULD BECOME ORGANIZED AND COULD PUSH BACK TOWARD THE
E/SE AND INTO THE FORECAST AREA THIS EVENING. FURTHER...THIS
CONVECTION COULD INTERACT WITH THE SEA BREEZE AND COULD PRODUCE
ISOLATED PULSE SEVERE WEATHER WITH DAMAGING WET MICROBURSTS MAINLY
INLAND THIS EVENING. THUS...POPS ARE ACTUALLY HIGHER AFTER 6 PM THAN
AT ANY TIME DURING THE DAY...ESPECIALLY INLAND. AFTER DARK...THE
SCENARIO BECOMES SOMEWHAT UNCERTAIN AND WILL DEPEND GREATLY ON THE
EVOLUTION OF THE EVENING CONVECTIVE REGIME. IN GENERAL...THE
FORECAST TAPERS POPS TO SLIGHT CHANCE ALL AREAS OVERNIGHT DUE TO
THE USUAL INFLUENCE OF DIURNAL STABILIZATION. EXCEPT WHERE RAIN
OCCURS...LOWS IN THE MID TO UPPER 70S WILL ONCE AGAIN PREVAIL MOST
AREAS TONIGHT.
THURSDAY AND FRIDAY...THE PATTERN AT THE SURFACE AND ALOFT WILL
BECOME MORE UNSETTLED FOR THE LATE WEEK PERIOD. DEEP LAYER RIDGING
WILL RETREAT FARTHER INTO THE ATLANTIC...AS AN AMPLIFYING UPPER
TROUGH SHIFTS OVER THE EAST COAST. SHORTWAVE ENERGY MOVING
DOWNSTREAM OF THE UPPER TROUGH AXIS WILL ALLOW THE INLAND SURFACE
TROUGH TO STRENGTHEN. A WEAK STATIONARY FRONT WILL LINGER OVER OR
JUST TO THE WEST OF THE FORECAST AREA THURSDAY...BEFORE
DISSIPATING NEAR THE COASTLINE FRIDAY. DEEP MOISTURE PROFILES WILL
DEEPEN WITHIN IMPROVED UPPER AND LOWER LEVEL FORCING...EVIDENT BY
PRECIPITABLE WATER VALUES RISING TO 2 INCHES LATE THURSDAY THROUGH
FRIDAY. HIGHER MOISTURE LEVELS AND SYNOPTIC SCALE FEATURES
ENHANCING TYPICAL SEABREEZE CONVECTION RAISES CONFIDENCE IN THE
DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS/THUNDERSTORMS. RAIN
CHANCES WILL PEAK IN THE 50 PERCENT RANGE EACH
AFTERNOON...DIMINISHING TO THE 20 TO 30 PERCENT RANGE DURING THE
OVERNIGHT HOURS WHEN BEST RAIN CHANCES TRANSITION TO THE MARINE
ZONES. HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN EARLIER IN
THE WEEK DUE TO LOWERING HEIGHTS ALOFT...THICKER CLOUDS AND BETTER
RAIN COVERAGE. EXPECT TEMPERATURES TO PEAK IN THE LOW TO MID 90S
AWAY FROM THE LOCALLY COOLER COASTLINE.
SATURDAY...UPPER RIDGING CENTERED OVER THE SOUTHERN PLAINS WILL
PRESS EASTWARD OVER THE WEEKEND...POSSIBLY DAMPENING THE EAST
COAST TROUGH. THERE IS SOME DISAGREEMENT BETWEEN MODEL SOLUTIONS
REGARDING THE EXTENT THE TROUGH LIFTS TO THE NORTH...WITH
DIFFERENCES IN CONVECTIVE POTENTIAL AS A RESULT. HOWEVER...BOTH
SOLUTIONS INDICATE THE INLAND SURFACE TROUGH PREVAILING AND
PRECIPITABLE WATER VALUES REMAINING NEAR 2 INCHES. WILL THUS LEAN
TOWARD SOLID THUNDERSTORM COVERAGE ONCE AGAIN...HIGHEST ALONG AND
INLAND OF THE SEABREEZE DURING THE AFTERNOON HOURS. HIGH
TEMPERATURES WILL REACH THE LOW TO MID 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
THE SOUTHEAST COAST WILL GENERALLY REMAIN BETWEEN A BROAD UPPER
TROUGH TO THE NORTH AND STRONG RIDGING JUST TO THE SOUTH INTO
EARLY NEXT WEEK. THE INLAND SURFACE TROUGH WILL BE FAIRLY WEAK ON
SUNDAY...THEN STEADILY STRENGTHEN MONDAY AND TUESDAY AHEAD OF AN
APPROACHING COLD FRONT FROM THE WEST ON WEDNESDAY. DEEP MOISTURE
CONTINUES TO BE QUITE HIGH THROUGH THE EXTENDED FORECAST
PERIOD...SUPPORTING AT LEAST SCATTERED THUNDERSTORM COVERAGE EACH
AFTERNOON AS TYPICAL SEABREEZE CONVECTION IS ENHANCED BY THE
SYNOPTIC SCALE FORCING. WILL ADVERTISE THUNDERSTORM CHANCES IN THE
30 TO NEAR 40 PERCENT RANGE DURING THE DAYTIME HOURS...DIMINISHING
OVER LAND AREAS EACH EVENING/NIGHT. HIGH TEMPERATURES WILL VARY
LITTLE THROUGH EARLY TO MID WEEK...REACHING THE LOW TO MID 90S
AWAY FROM THE LOCALLY COOLER COASTLINE.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
ODDS STILL FAVOR VFR CONDITIONS THROUGH TONIGHT. THUNDERSTORMS COULD
DEVELOP AND/OR MOVE INTO THE VICINITY OF THE TERMINALS...PERHAPS
AS THE SEA BREEZE PUSHES INLAND 18-21Z AND AGAIN AFTER 21-00Z AS INLAND
CONVECTION ATTEMPTS TO ADVANCE TOWARD THE COAST. HOWEVER...MID
LEVEL DRY AIR/CAPPING COULD PREVENT ANY CONVECTION NEAR THE
TERMINALS...THUS OPTED TO OMIT ANY MENTION OF VCTS/CBS FROM 12Z
TAFS. WILL CONTINUE TO ASSESS AND WILL AMEND AS NEEDED BASED ON
SHORT/NEAR TERM CONVECTIVE TRENDS THIS AFTERNOON AND TONIGHT.
EXTENDED AVIATION OUTLOOK...THERE WILL BE INCREASING CHANCES FOR
BRIEF FLIGHT RESTRICTIONS IN SHOWERS/THUNDERSTORMS BY THURSDAY
AFTERNOON...CONTINUING INTO SATURDAY...AS DEEP LAYER MOISTURE
INCREASES CONVECTIVE COVERAGE WITHIN A BROAD UPPER LEVEL TROUGH
OVER THE EASTERN UNITED STATES.
&&
.MARINE...
W/SW WINDS 10-15 KT THIS MORNING...AS HIGH AS 15-20 KT BEYOND 20 NM...
WILL GIVE WAY TO A VIGOROUS SEA BREEZE CIRCULATION PRODUCING
ONSHORE WINDS AS HIGH AS 15-20 KT ESPECIALLY WITHIN NEARSHORE
WATERS THIS AFTERNOON/EVENING. TONIGHT...S/SW WINDS AS HIGH AS
15-20 KT WILL PREVAIL. SEAS WILL AVERAGE 3-4 FT MOST AREAS. BEYOND
20 NM...SEAS AS HIGH AS 5 FT WILL OCCUR THIS MORNING AND COULD
OCCUR AGAIN TONIGHT.
THURSDAY THROUGH SUNDAY...THE ATLANTIC RIDGE WILL SHIFT FARTHER
OUT TO SEA BY THE LATE WEEK PERIOD...AS A BROAD TROUGH OF LOW
PRESSURE BUILDS OVER THE EAST AND SOUTHEAST UNITED STATES. THIS
PATTERN CHANGE WILL RESULT IN MORE SOLID SOUTHERLY WINDS AND
INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS. NOCTURNAL SURGES
UP TO 15 TO 20 KT ARE POSSIBLE EACH NIGHT...HOWEVER CONDITIONS ARE
STILL EXPECTED TO REMAIN BELOW ADVISORY CONDITIONS OUTSIDE OF
THUNDERSTORMS.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...ECT
SHORT TERM...SPR/WMS
LONG TERM...WMS
AVIATION...ECT/SPR
MARINE...ECT/WMS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
100 PM CDT WED JUL 9 2014
.DISCUSSION...
335 AM CDT
LOW HUMIDITY AND MILD CONDITIONS ON TAP THROUGH MUCH OF THE
REMAINDER OF THE WORK WEEK BEFORE A TRANSITION TOWARD WARMER...MORE
HUMID...AND UNSETTLED CONDITIONS JUST IN TIME FOR THE WEEKEND.
WEAK BACK DOOR FRONT IS WORKING ITS WAY DOWN THE LAKE EARLY THIS
MORNING WITH A WIND SHIFT TO NORTHEAST AND A DECENT PUSH OF MARINE
COOLING AND SOME LOW CLOUDS AND FOG NEAR THE LAKE. GIVEN THE DRIER
AIR MASS UPSTREAM...ANTICIPATE ANY LAKE CLOUDS/FOG SHOULD MIX OUT
PRETTY READILY BY MID TO LATE MORNING...THOUGH WINDS OFF THE LAKE
THROUGH THE DAY SHOULD KEEP TEMPS IN THE 60S AT THE BEACHES TODAY
WHILE INLAND TEMPS REBOUND INTO THE 70S. MINUS THE LAKE CLOUDS AND
PERHAPS BEING A COUPLE DEGREES WARMER...THURSDAY LOOKS TO BE A
CARBON COPY OF TODAY.
THE MAJORITY OF GUIDANCE HAS LARGELY SLOWED THE DEPARTURE OF THE
UPPER TROUGH AND RETURN OF BETTER MOISTURE AND INSTABILITY LATER THIS
WEEK. THIS COULD RESULT IN MOST OF FRIDAY POTENTIALLY ENDING UP
DRY...ESPECIALLY EASTERN CWA. RAIN CHANCES WILL RAMP UP FRIDAY NIGHT
AND CONTINUE AT TIMES THROUGH THE WEEKEND WITH A PERTURBED
WEST-NORTHWESTERLY FLOW ALOFT. TEMPERATURES OVER THE WEEKEND
GENERALLY LOOK WARMER WITH MORE HUMIDITY...THOUGH ILL-TIMED MCS
AND/OR DEBRIS CLOUD COVER CERTAINLY COULD PLAY A ROLE IN KEEPING
TEMPS COOLER.
GFS/ECMWF BOTH REMAIN IN GOOD AGREEMENT ON AMPLIFYING AND
UNSEASONABLY DEEP UPPER TROUGH OVER THE REGION NEXT WEEK PROVIDING
FOR A PERIOD OF UNSEASONABLY COOL TEMPERATURES. ECMWF HAS BEEN
DROPPING 850MB TEMPS INTO THE MID SINGLE DIGIT RANGE BY TUES/WED
WHICH IS GETTING TO THE LOWER BOUNDS OF WHAT WE SEE AROUND HERE IN
JULY. NOT UNCOMMON FOR MODELS TO BE A BIT TOO AGGRESSIVE WITH COLD
SNAPS IN THE DAYS 6 AND BEYOND RANGE...BUT REGARDLESS IT LOOKS LIKE
BELOW AVERAGE TEMPS NEXT WEEK ARE QUITE LIKELY.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* LAKE BREEZE TIMING...NORTHWEST WINDS SHIFTING TO THE EAST
NORTHEAST WITH SPEEDS AT OR ABOVE 10KT.
RODRIGUEZ
//DISCUSSION...UPDATED 18Z...
QUIET CONDITIONS ACROSS THE TERMINALS AT THIS TIME WITH THESE
QUIET AND VFR CONDITIONS EXPECTED TO REMAIN THROUGH THE REST OF
THE FORECAST PERIOD. THE ONLY CONCERN IS WITH THE LAKE BREEZE AND
TIMING THIS AFTERNOON. MOVEMENT OF THE LAKE BREEZE HAS BEEN
VARIABLE OVER THE LAST HOUR...WITH LOWER LEVEL SPEEDS STILL ON THE
HIGHER SIDE. EXPECT THESE STRONGER WESTERLY WINDS TO DIMINISH
EARLY THIS AFTERNOON WHILE THE CURRENT SLOW WESTWARD MOVEMENT
INCREASES. CONFIDENCE IS HIGHER WITH LAKE BREEZE TIMING FOR MDW
WITH IT RAPIDLY APPROACHING AT THIS HOUR. WILL CONTINUE TO MONITOR
TIMING FOR ORD...ESPECIALLY WITH SOME INCREASE IN THIS MOVEMENT
ANTICIPATED.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN VFR CONDITIONS.
* HIGH CONFIDENCE OF LAKE BREEZE WIND SHIFT...MEDIUM HIGH
CONFIDENCE WITH SPEEDS...MEDIUM CONFIDENCE WITH EXACT TIMING.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR
FRIDAY THROUGH SUNDAY...GENERALLY VFR WITH A CHANCE OF SHOWERS
AND THUNDERSTORMS EACH DAY.
MONDAY AND TUESDAY...VFR.
KJB
&&
.MARINE...
216 AM CDT
A COLD FRONT IS CURRENTLY SHIFTING SOUTHWARD ACROSS THE SOUTHERN END
OF THE LAKE...WITH THE WINDS SHIFTING OUT OF THE NORTH DIRECTLY IN
ITS WAKE. IN SPITE OF THIS...A BROAD AREA OF HIGH PRESSURE WILL
CONTINUE TO BUILD ACROSS THE WESTERN GREAT LAKES REGION THROUGH THE
DAY. THIS WILL RESULT IN THE DEVELOPMENT OF A LIGHT AND SOMEWHAT
VARIABLE WIND FIELD ACROSS THE LAKE TODAY INTO THURSDAY.
HOWEVER...LAKE BREEZE INFLUENCES WILL LIKELY LEAD TO AN
ONSHORE FLOW REGIME ACROSS THE NEAR SHORE WATERS DURING THE DAY TIME
HOURS WEDNESDAY AND THURSDAY.
THE SURFACE HIGH IS EXPECTED TO SHIFT EASTWARD TOWARDS THE ATLANTIC
COAST LATER IN THE WEEK. AS THIS OCCURS...IT SHOULD ALLOW THE FLOW
TO SHIFT BACK OUT OF THE SOUTH OVER THE LAKE INTO THE WEEKEND. IN
ADDITION...INCREASING MOISTURE AND ADDITIONAL WEATHER DISTURBANCES
LOOK TO INCREASE THE CHANCES FOR SHOWERS AND STORMS AGAIN FOR FRIDAY
AND INTO THE WEEKEND.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1204 PM CDT Wed Jul 9 2014
.DISCUSSION...
ISSUED 1005 AM CDT Wed Jul 9 2014
Weak surface trough located roughly along I-70 at 10 am, with some
clouds recently developing along it. These will push east of the
forecast area in the next couple hours. Remainder of the forecast
area currently clear, although visible satellite imagery showing a
large area of smoke aloft streaming southeast from the northern
Plains, which has started to brush across western Illinois.
Moisture cross-sections from the RAP model showing some lingering
clouds into early afternoon in southeast Illinois, but subsidence
will keep the remainder of the forecast area mainly sunny.
Made some minor adjustments to the hourly temperatures, which
tweaked the highs by a degree or two. Updated grids have been
sent, but the zone forecasts still appear OK.
Geelhart
&&
.AVIATION...
ISSUED 1200 PM CDT Wed Jul 9 2014
VFR conditions will prevail over the next 24 hours. Have been
seeing some diurnal cumulus developing around 5000 feet late this
morning, but this should fade with sunset. Northwest winds this
afternoon will diminish and gradually turn more northeast
overnight, as an area of high pressure drifts across Lake Michigan.
Expect scattered clouds developing again around the same time on
Thursday, although there could be some slightly thicker coverage.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Wed Jul 9 2014
SHORT TERM...Today through Sunday
00Z models are in fair agreement the rest of the work week and
show a more unsettled weather pattern taking shape from Friday
through Monday.
Quiet weather expected through Thu night across central IL with
mostly clear skies and more comfortable humidity levels with
dew points in the upper 50s and lower 60s. Lows in the upper 50s
and lower 60s tonight and Thu night. Highs in the lower 80s today
and Thu with a few upper 70s NE areas. Weak 1018 mb high pressure
over the Plains to settle into MI tonight/Thu bringing the fair
weather to IL. Scattered cumulus clouds to appear late morning and
afternoon and more prevalent in southeast IL.
High pressure strengthens as it shifts into the eastern Great
Lakes and New England Friday with a return southerly flow setting
up over IL. This to bring warmer and more humid air back into the
area especially by Saturday/Sunday. A short wave near the western
states to ridge over top of broad/flat upper level ridge over
central Plains/Rockies and move into WI/IL Friday. This to bring
next chance of showers and thunderstorms to mainly areas from I-57
west Friday and across area Friday night & Saturday. Highs Friday
in low to mid 80s and mid to upper 80s Saturday/Sunday. Dew points
elevate into the mid to upper 60s Friday afternoon (highest
western IL) and low to mid 70s Saturday/Sunday.
LONG TERM...Sunday night through Wednesday
A couple of short waves pass ESE through IL this weekend into
Monday and continue daily chances of showers and thunderstorms in
tropical air mass. Upper level trof digging southward into the
Midwest and Great Lakes region early next week to also drive a
cold front south through central IL Monday afternoon/Monday night.
Cooler temperatures expected behind it Tue/Wed with highs in the
70s and less humid air returning.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1115 AM CDT WED JUL 9 2014
.DISCUSSION...
335 AM CDT
LOW HUMIDITY AND MILD CONDITIONS ON TAP THROUGH MUCH OF THE
REMAINDER OF THE WORK WEEK BEFORE A TRANSITION TOWARD WARMER...MORE
HUMID...AND UNSETTLED CONDITIONS JUST IN TIME FOR THE WEEKEND.
WEAK BACK DOOR FRONT IS WORKING ITS WAY DOWN THE LAKE EARLY THIS
MORNING WITH A WIND SHIFT TO NORTHEAST AND A DECENT PUSH OF MARINE
COOLING AND SOME LOW CLOUDS AND FOG NEAR THE LAKE. GIVEN THE DRIER
AIR MASS UPSTREAM...ANTICIPATE ANY LAKE CLOUDS/FOG SHOULD MIX OUT
PRETTY READILY BY MID TO LATE MORNING...THOUGH WINDS OFF THE LAKE
THROUGH THE DAY SHOULD KEEP TEMPS IN THE 60S AT THE BEACHES TODAY
WHILE INLAND TEMPS REBOUND INTO THE 70S. MINUS THE LAKE CLOUDS AND
PERHAPS BEING A COUPLE DEGREES WARMER...THURSDAY LOOKS TO BE A
CARBON COPY OF TODAY.
THE MAJORITY OF GUIDANCE HAS LARGELY SLOWED THE DEPARTURE OF THE
UPPER TROUGH AND RETURN OF BETTER MOISTURE AND INSTABILITY LATER THIS
WEEK. THIS COULD RESULT IN MOST OF FRIDAY POTENTIALLY ENDING UP
DRY...ESPECIALLY EASTERN CWA. RAIN CHANCES WILL RAMP UP FRIDAY NIGHT
AND CONTINUE AT TIMES THROUGH THE WEEKEND WITH A PERTURBED
WEST-NORTHWESTERLY FLOW ALOFT. TEMPERATURES OVER THE WEEKEND
GENERALLY LOOK WARMER WITH MORE HUMIDITY...THOUGH ILL-TIMED MCS
AND/OR DEBRIS CLOUD COVER CERTAINLY COULD PLAY A ROLE IN KEEPING
TEMPS COOLER.
GFS/ECMWF BOTH REMAIN IN GOOD AGREEMENT ON AMPLIFYING AND
UNSEASONABLY DEEP UPPER TROUGH OVER THE REGION NEXT WEEK PROVIDING
FOR A PERIOD OF UNSEASONABLY COOL TEMPERATURES. ECMWF HAS BEEN
DROPPING 850MB TEMPS INTO THE MID SINGLE DIGIT RANGE BY TUES/WED
WHICH IS GETTING TO THE LOWER BOUNDS OF WHAT WE SEE AROUND HERE IN
JULY. NOT UNCOMMON FOR MODELS TO BE A BIT TOO AGGRESSIVE WITH COLD
SNAPS IN THE DAYS 6 AND BEYOND RANGE...BUT REGARDLESS IT LOOKS LIKE
BELOW AVERAGE TEMPS NEXT WEEK ARE QUITE LIKELY.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* E-NE WINDS LIKELY BY MID AFTERNOON WITH A LAKE BREEZE FOR
ORD...AND EARLY AFTERNOON FOR MDW. SPEEDS NEAR 10 KT POSSIBLE.
KJB/RODRIGUEZ
//DISCUSSION...UPDATED 12Z...
THE MAIN WEATHER CONCERNS DURING THE DAY...WILL BE THE WIND
TRENDS WITH A LAKE BREEZE LIKELY TO APPROACH THE TERMINALS BY MID
TO LATE AFTERNOON. THIS LOOKS TO LEAD TO A WIND SHIFT OUT OF THE
EAST-NORTHEAST AFTER 20 UTC. HOWEVER...WIND SPEEDS LOOK TO REMAIN
AT OR JUST UNDER 10 KT THROUGH THE DAY.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH IN E-NE WINDS AROUND 10 KT THIS AFTERNOON...BUT LOW MEDIUM
ON EXACT TIMING.
KJB/RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR
FRIDAY THROUGH SUNDAY...GENERALLY VFR WITH A CHANCE OF SHOWERS
AND THUNDERSTORMS EACH DAY.
MONDAY AND TUESDAY...VFR.
KJB
&&
.MARINE...
216 AM CDT
A COLD FRONT IS CURRENTLY SHIFTING SOUTHWARD ACROSS THE SOUTHERN END
OF THE LAKE...WITH THE WINDS SHIFTING OUT OF THE NORTH DIRECTLY IN
ITS WAKE. IN SPITE OF THIS...A BROAD AREA OF HIGH PRESSURE WILL
CONTINUE TO BUILD ACROSS THE WESTERN GREAT LAKES REGION THROUGH THE
DAY. THIS WILL RESULT IN THE DEVELOPMENT OF A LIGHT AND SOMEWHAT
VARIABLE WIND FIELD ACROSS THE LAKE TODAY INTO THURSDAY.
HOWEVER...LAKE BREEZE INFLUENCES WILL LIKELY LEAD TO AN
ONSHORE FLOW REGIME ACROSS THE NEAR SHORE WATERS DURING THE DAY TIME
HOURS WEDNESDAY AND THURSDAY.
THE SURFACE HIGH IS EXPECTED TO SHIFT EASTWARD TOWARDS THE ATLANTIC
COAST LATER IN THE WEEK. AS THIS OCCURS...IT SHOULD ALLOW THE FLOW
TO SHIFT BACK OUT OF THE SOUTH OVER THE LAKE INTO THE WEEKEND. IN
ADDITION...INCREASING MOISTURE AND ADDITIONAL WEATHER DISTURBANCES
LOOK TO INCREASE THE CHANCES FOR SHOWERS AND STORMS AGAIN FOR FRIDAY
AND INTO THE WEEKEND.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1007 AM CDT Wed Jul 9 2014
.DISCUSSION...
ISSUED 1005 AM CDT Wed Jul 9 2014
Weak surface trough located roughly along I-70 at 10 am, with some
clouds recently developing along it. These will push east of the
forecast area in the next couple hours. Remainder of the forecast
area currently clear, although visible satellite imagery showing a
large area of smoke aloft streaming southeast from the northern
Plains, which has started to brush across western Illinois.
Moisture cross-sections from the RAP model showing some lingering
clouds into early afternoon in southeast Illinois, but subsidence
will keep the remainder of the forecast area mainly sunny.
Made some minor adjustments to the hourly temperatures, which
tweaked the highs by a degree or two. Updated grids have been
sent, but the zone forecasts still appear OK.
Geelhart
&&
.AVIATION...
ISSUED 645 AM CDT Wed Jul 9 2014
Despite the passage of a weak surface trough today, VFR conditions
should prevail over the next 24 hours. A layer of moisture in the
4k ft level will develop into scattered cumulus during the heat of
the day. A couple of forecast models are indicating a few showers
could develop ahead of the trough, but better chances should
remain southeast of the terminal sites this afternoon.
Winds will start out westerly this morning, then veer to the NW
with the trough passage and increase to around 10kt. Winds will
weaken with sunset and continue veering to the N-NE overnight.
Any reductions to visibility tonight due to fog will be minor and
remain VFR.
Shimon
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Wed Jul 9 2014
SHORT TERM...Today through Sunday
00Z models are in fair agreement the rest of the work week and
show a more unsettled weather pattern taking shape from Friday
through Monday.
Quiet weather expected through Thu night across central IL with
mostly clear skies and more comfortable humidity levels with
dew points in the upper 50s and lower 60s. Lows in the upper 50s
and lower 60s tonight and Thu night. Highs in the lower 80s today
and Thu with a few upper 70s NE areas. Weak 1018 mb high pressure
over the Plains to settle into MI tonight/Thu bringing the fair
weather to IL. Scattered cumulus clouds to appear late morning and
afternoon and more prevalent in southeast IL.
High pressure strengthens as it shifts into the eastern Great
Lakes and New England Friday with a return southerly flow setting
up over IL. This to bring warmer and more humid air back into the
area especially by Saturday/Sunday. A short wave near the western
states to ridge over top of broad/flat upper level ridge over
central Plains/Rockies and move into WI/IL Friday. This to bring
next chance of showers and thunderstorms to mainly areas from I-57
west Friday and across area Friday night & Saturday. Highs Friday
in low to mid 80s and mid to upper 80s Saturday/Sunday. Dew points
elevate into the mid to upper 60s Friday afternoon (highest
western IL) and low to mid 70s Saturday/Sunday.
LONG TERM...Sunday night through Wednesday
A couple of short waves pass ESE through IL this weekend into
Monday and continue daily chances of showers and thunderstorms in
tropical air mass. Upper level trof digging southward into the
Midwest and Great Lakes region early next week to also drive a
cold front south through central IL Monday afternoon/Monday night.
Cooler temperatures expected behind it Tue/Wed with highs in the
70s and less humid air returning.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
616 PM CDT Thu Jul 10 2014
...Updated aviation discussion...
.SHORT TERM...(This evening through Friday)
ISSUED AT 334 PM CDT THU JUL 10 2014
A warm front advancing north across southwest Kansas late this
afternoon will be the focus for an isolated thunderstorm or two, and
will carry some 15 to 20 POPs along a 50-60 mile wide corridor from
roughly Lakin down to Kismet, but late afternoon 1km visible
satellite was only showing moderate cumulus, with most of it being
south of the warm front where the boundary layer was well-mixed.
Should a storm form, damaging downburst winds to 60 mph would be the
only real concern. The tight pressure gradient (by mid July
standards) will continue through the night with winds staying up in
the 15 to 20 mph much of the night. The 500mb ridge will be parked
right over southwest Kansas tomorrow with nearly calm winds at this
level of the mid troposphere. Winds will be quite a bit stronger in
the lower troposphere with the lee trough holding strong through
Friday afternoon. Surface winds 25 to 30 mph sustained should be
realized by early afternoon with some gusts 35 to 40 mph out of the
south-southwest. The low level thermal ridge will be from
east-central Colorado northeast into far southwest Nebraska, so this
is the area where 100-degree heat should be found. We will continue
to carry the warmest afternoon temperatures across the far northwest
zones as a result (mainly northwest of a Syracuse to Hays line).
Elsewhere, upper 90s will still be common. The boundary layer
convergence will be found well north of the southwest Kansas region
as well, so surface-based thunderstorms will develop up in this
area, and we will be removing POPs across far west-central and
southwest Kansas.
.LONG TERM...(Friday night through Thursday)
ISSUED AT 222 PM CDT THU JUL 10 2014
Friday Night/Saturday:
Went ahead and removed >14 pops and resultant weather for Friday Night.
The global models, as well as convective allowing models show any storms
remaining across Colorado and possibly into northwest Kansas. SW Kansas
will be capped off and firmly in the warm sector, so not expecting
thunderstorms at this time. Lows will be warm and in the 70s.
Kept the highest pops for Saturday afternoon and evening across the
northwest zones in association to closer proximity to the front. There
is a trend that the models are backing off on the convective signal,
so this may have to be cut back in future forecasts. Otherwise, a hot
day is expected with max values in the 95-101F range. Another mild night
with 70s for lows is expected heading into Sunday morning.
Sunday and beyond:
Will have to watch out for upslope/post-frontal convection Sunday across
the western zones, which the EC has been consistently showing. Maximum
temperatures will be a few degrees cooler and in the mid 90s.
The most significant item of interest is another fairly strong cold
front that moves across the region late Monday into Tuesday. Thunderstorms
will be possible along the front and then possibly later in a post-
frontal upslope flow regime. The airmass behind this front is quite
impressive for July standards (the 12Z EC solution). 850-hPa temperatures
in the lower teens C is quite the anomaly for this time of year. This
translates to surface temperatures in the 70s for highs and 50s! for
lows, which is from the raw EC output and matches pretty well with ECE
guidance. FWIW, the record low for the 16th for Dodge City is 51F.
I do have some 50s in there now for the middle portion of next week,
but don`t want to jump on the near record approaching outlier just yet.
Regardless, it will be wonderful next week temperatures-wise, with
widespread 70s rather than your typical 90s.
Allblend pops and temps were pretty much left alone since it looks
very reasonable.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 612 PM CDT THU JUL 10 2014
Warm front will slowly move northeast across western Kansas
overnight. The RAP and NAM was doing a decent job on movement of this
front based on 21z surface analysis so will follow these models
for the wind shift as this surface boundary passes. Gusty winds
will decrease after sunset to 10 to 15 knots. The Winds are
expected to shift to the south/southwest as this front passes
Dodge City and Garden City between 00z and 03z. Hays will keep a
southeast wind throughout the night. Cloud cover this evening due
to late day heating will give way to clearing skies after 02z. Cloud
bases early tonight based on model soundings will be above the
6000ft AGL. Gusty southwest winds will develop by late Friday morning
across all of western Kansas as an area of low pressure at the
surface develop near northwest Kansas and stronger boundary layer
winds mix down to the surface.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 71 98 71 98 / 10 10 10 10
GCK 70 99 70 97 / 20 10 10 10
EHA 69 97 70 96 / 10 10 10 10
LBL 70 99 71 100 / 20 10 10 10
HYS 72 99 72 96 / 10 10 10 30
P28 72 98 73 101 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Sugden
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
246 PM CDT Wed Jul 9 2014
...Update to long term...
.SHORT TERM...(This evening through Thursday)
ISSUED AT 205 PM CDT WED JUL 9 2014
The main challenge in the forecast tonight and Thursday is
precipitation chances, extent, and thunderstorm severity.
Surface-based thunderstorms are expected to develop across northeast
Colorado in vicinity of, or just downstream of Cheyenne Ridge. The
former runs (00Z) of the WRF-ARW and WRF-NMMB cores suggested a
small MCS would develop and roll southeast toward far west-central
Kansas. The latest 12Z runs of both the models, however, are less
aggressive with this idea. That being said, the HRRR (using WRF-ARW
core) late morning runs insist on northeast Colorado activity
evolving southeast through the evening across northeastern Kansas
and eventually into our far northwestern zones (Syracuse to Scott
City). We will maintain some Chance POPs in the far west-central
Kansas counties north of Hwy 50 and generally west of Hwy 283
through the evening.
Another MCS will either roll south-southeast out of Nebraska and
interact with the western MCS or remain a separate entity all
together and redevelop around 04-06Z across north central/central
Kansas along a strengthening zone of warm frontogenesis in the
850-750mb layer. We will have some 40 POPs from Hays to Pratt in the
05-12Z time frame, but these may need to be raised early this
evening if short term trends favor a more western scenario for
potential MCS. The overall severe weather threat looks fairly
minimal, despite a SLGT risk being issued by SPC. Any large hail
threat would be confined to areas of far west-central Kansas (but
more likely across northeastern Colorado and northwestern Kansas)
with strong straight-line winds to 65 mph the most likely threat
with any bowing segments during the mid to late evening hours. After
that, a very heavy rain threat will develop during the overnight
hours across central Kansas. It remains to be seen, though, how far
west the core of the nocturnal MCS will be. It seems most likely
this will stay across portions of central and south central Kansas
just east of our forecast area (east of a Hays to Pratt line).
Going in to the day Thursday, a warmer day is forecast with warmer
overall temperatures in the lower troposphere (to +29C at 850mb as
far east as the Hwy 283 corridor). This should allow surface
temperatures late afternoon reaching close to, if not 100F
(especially along/west of Hwy 83 where evapotransporation will be
less). A fairly strong gradient will yield a windier day with
south-southwest winds 20 to 23 knots sustained in the afternoon.
.LONG TERM...(Thursday night through Wednesday)
ISSUED AT 246 PM CDT WED JUL 9 2014
Thursday night/Friday:
Minimums overnight Thursday will be quite mild - 70s - as southerly
winds continue through the overnight in association with continued
surface lee troughing.
Friday will be a hot day with max values at 97-100F. There will be
a slight chance for tstms from Hugoton to Hays and points west, but
convection may remain out of the area and limited to eastern Colorado
and into southwest Nebraska. Another mild night with widespread 70s
for lows is expected heading into Saturday morning.
Saturday and beyond:
A slightly better chance of coverage of storms is expected Saturday
as a frontal boundary sinks farther to the south across Kansas. Ahead
of the front, temperatures will be quite hot with values around 100F.
A weak cool down is expected Sunday as the front heads south and slightly
cooler 850-hPa temperatures advect across the region. Will have to watch
out for convection across the western zones in this upslope flow pattern.
The EC indicates another shot for an MCS Monday, as northwesterly flow
aloft and low-level upslope flow continues across the High Plains.
The best chance for precip area-wide is expected Tuesday as a rather
cold air mass (for July standards) moves across the Plains. The EC has
been very consistent with this cool down and associated precipitation.
850-hPa temperatures by the middle portion of next decrease as low as
8-10C! Very pleasant and highly abnormal Summer weather in regards to
temperatures is possible in about a week from now with highs in the
70/80s and lows possibly in the 50s! The front could slow down, so exact
timing is in question. Stuck with the allblend temperature solution
for now.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1152 AM CDT WED JUL 9 2014
The lee trough will continue to strengthen across eastern Colorado,
increasing the pressure gradient and resulting surface winds. Wind
speeds during the afternoon hours will range from 15 to 19 knots
with gusts in the mid to upper 20s knots out of the southeast. Winds
will decrease slightly during the overnight hours. At this time,
thunderstorm activity will not be included in any three of the
terminals (DDC, GCK, HYS) given low confidence of any thunderstorm
impacts. Thunderstorms will likely make an approach to GCK late this
evening, however more than likely in a weakening state (or even
completely dissolved by the time they reach GCK). Another overnight
cluster of thunderstorms will develop across central Kansas, but HYS
appears to be on the western edge of any of this activity with a
much higher probability of thunderstorms east of HYS overnight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 97 72 98 / 10 10 0 10
GCK 66 98 71 99 / 20 10 0 20
EHA 68 98 71 97 / 20 0 0 20
LBL 68 99 71 99 / 10 0 0 10
HYS 66 95 72 99 / 40 10 10 20
P28 68 96 72 98 / 20 30 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Sugden
AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
207 PM CDT Wed Jul 9 2014
...Updated Short Term Section...
.SHORT TERM...(This evening through Thursday)
ISSUED AT 205 PM CDT WED JUL 9 2014
The main challenge in the forecast tonight and Thursday is
precipitation chances, extent, and thunderstorm severity.
Surface-based thunderstorms are expected to develop across northeast
Colorado in vicinity of, or just downstream of Cheyenne Ridge. The
former runs (00Z) of the WRF-ARW and WRF-NMMB cores suggested a
small MCS would develop and roll southeast toward far west-central
Kansas. The latest 12Z runs of both the models, however, are less
aggressive with this idea. That being said, the HRRR (using WRF-ARW
core) late morning runs insist on northeast Colorado activity
evolving southeast through the evening across northeastern Kansas
and eventually into our far northwestern zones (Syracuse to Scott
City). We will maintain some Chance POPs in the far west-central
Kansas counties north of Hwy 50 and generally west of Hwy 283
through the evening.
Another MCS will either roll south-southeast out of Nebraska and
interact with the western MCS or remain a separate entity all
together and redevelop around 04-06Z across north central/central
Kansas along a strengthening zone of warm frontogenesis in the
850-750mb layer. We will have some 40 POPs from Hays to Pratt in the
05-12Z time frame, but these may need to be raised early this
evening if short term trends favor a more western scenario for
potential MCS. The overall severe weather threat looks fairly
minimal, despite a SLGT risk being issued by SPC. Any large hail
threat would be confined to areas of far west-central Kansas (but
more likely across northeastern Colorado and northwestern Kansas)
with strong straight-line winds to 65 mph the most likely threat
with any bowing segments during the mid to late evening hours. After
that, a very heavy rain threat will develop during the overnight
hours across central Kansas. It remains to be seen, though, how far
west the core of the nocturnal MCS will be. It seems most likely
this will stay across portions of central and south central Kansas
just east of our forecast area (east of a Hays to Pratt line).
Going in to the day Thursday, a warmer day is forecast with warmer
overall temperatures in the lower troposphere (to +29C at 850mb as
far east as the Hwy 283 corridor). This should allow surface
temperatures late afternoon reaching close to, if not 100F
(especially along/west of Hwy 83 where evapotransporation will be
less). A fairly strong gradient will yield a windier day with
south-southwest winds 20 to 23 knots sustained in the afternoon.
.LONG TERM...(Thursday through Tuesday)
ISSUED AT 155 AM CDT WED JUL 9 2014
Thunderstorms are likely across portions of central Kansas early
Thursday morning as an upper level shortwave coming off the ridge
axis across the Colorado Rockies dips southeast across the Central
Plains. Increased convergence/forcing ahead of the advancing surface
trough along with ample low/mid level moisture will be enough to
support convection across central Kansas as the aforementioned
shortwave dives southeast across the region. Drier conditions
are then likely Thursday afternoon through Friday afternoon as
the upper level ridge axis shifts eastward across the Western
High Plains. Going into the weekend, medium range models indicate
the upper level ridge breaking down somewhat as it moves further
east into the Central Plains returning a southwest flow aloft to
portions of the Rocky Mountain Region. The GFS/ECMWF hint at H5
vort maxima ejecting eastward out of the Central Rockies providing
the focus for possible thunderstorms lee of the front range Friday
night into Saturday. Although the flow aloft will remain fairly
weak, forcing associated with a surface trough and enough
instability will exist to support thunderstorm development across
eastern Colorado late Friday afternoon with storms potentially
moving into western Kansas overnight through early Saturday.
Warmer temperatures are likely Thursday as a prevailing lee side
trough continues to influence a southerly flow across western
Kansas. This will enhance warm air advection into the area with
H85 temperatures climbing into the mid 20s(C) across central Kansas
to near 30C closer to the Colorado border. Highs will reach well
into the 90s(F) Thursday afternoon with similar highs expected
each day going into the weekend as upper level ridging moves out
of the Rockies across the Western High Plains.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 1152 AM CDT WED JUL 9 2014
The lee trough will continue to strengthen across eastern Colorado,
increasing the pressure gradient and resulting surface winds. Wind
speeds during the afternoon hours will range from 15 to 19 knots
with gusts in the mid to upper 20s knots out of the southeast. Winds
will decrease slightly during the overnight hours. At this time,
thunderstorm activity will not be included in any three of the
terminals (DDC, GCK, HYS) given low confidence of any thunderstorm
impacts. Thunderstorms will likely make an approach to GCK late this
evening, however more than likely in a weakening state (or even
completely dissolved by the time they reach GCK). Another overnight
cluster of thunderstorms will develop across central Kansas, but HYS
appears to be on the western edge of any of this activity with a
much higher probability of thunderstorms east of HYS overnight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 97 72 98 / 10 10 0 10
GCK 66 98 71 99 / 20 10 0 20
EHA 68 98 71 97 / 20 0 0 20
LBL 68 99 71 99 / 10 0 0 10
HYS 66 95 72 99 / 40 10 10 20
P28 68 96 72 98 / 20 30 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...JJohnson
AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS JACKSON KY
124 AM EDT WED JUL 9 2014
.UPDATE...
ISSUED AT 124 AM EDT WED JUL 9 2014
ISOLATED TO SCATTERED SHOWERS AND STORMS CONTINUE TO WORK EAST ACROSS
THE AREA. IT LOOKS LIKE THERE IS A BACK EDGE TO THE RAIN CHANCES
PUSHING INTO CENTRAL KENTUCKY. IT LOOKS LIKE THE THREAT OF SHOWERS
AND STORMS SHOULD CONTINUE OVER THE NEXT 2 TO 4 HOURS BEFORE THE
THREAT EXITS TO THE SOUTHEAST. POPS/WEATHER HAVE BEEN UPDATED TO
REFLECT THIS TREND.
UPDATE ISSUED AT 1100 PM EDT TUE JUL 8 2014
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT TRENDS. SOME ISOLATED
TO SCATTERED ACTIVITY IS EXPECTED TI MOST AREAS OVERNIGHT
THOUGH...ACTIVITY WILL BE MORE WIDESPREAD NEAR THE TN BORDER AND
PARTS OF THE VA BORDER. SOME LOCALLY HEAVIER RAIN HAS FALLEN OVER
PARTS OF BELL COUNTY BUT RAIN GAGES NEAR MIDDLESBORO SUGGEST THE
RADAR ESTIMATES ARE OVERDONE.
UPDATE ISSUED AT 830 PM EDT TUE JUL 8 2014
THE GRIDS HAVE BEEN UPDATED BASED ON OBSERVATION AND RADAR TRENDS.
EARLIER SHOWERS AND SOME STORMS HAVE STABILIZED THE ATMOSPHERE OVER
THE NORTHEAST TWO THIRDS OF THE AREA AND WARM AIR AND ASSOCIATED
RATHER STABLE LAPSE RATES BETWEEN 400 AND 500 MB CONTINUES TO BE A
LIMITING FACTOR TO CONVECTION DESPITE OTHER FAVORABLE PARAMETERS.
CONVECTION NEAR THE TN BORDER SHOULD CONTINUE TO BE RATHER WIDESPREAD
OVER THE NEXT COUPLE OF HOURS. AS THE COLD FRONT WORKS INTO THE
REGION OVERNIGHT AND THE SHORTWAVE TROUGH AXIS MOVES THROUGH SOME
ISOLATED TO SCATTERED REDEVELOPMENT MAY OCCUR...BUT THIS ACTIVITY
SHOULD BE A BENEFICIAL RAIN EVENT WHERE IT OCCURS.
UPDATE ISSUED AT 454 PM EDT TUE JUL 8 2014
STORMS CONTINUE TO HAVE A HARD TIME ORGANIZING. UPDRAFTS DO NOT
APPEAR TO BE ABLE TO MUSTER ENOUGH STRENGTH TO OVERCOME SOME WARM AIR
BETWEEN 400 AND 500 MB. MODEL SOUNDINGS DO NOT SHOW THIS WARM LAYER
GOING AWAY. AN ISOLATED SEVERE THUNDERSTORM WITH GUSTY WINDS CANNOT
BE RULED OUT INTO THE EVENING...BUT SEVERE THREAT APPEARS TO BE
DWINDLING.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 258 PM EDT TUE JUL 8 2014
STORMS HAVE BEEN A LITTLE SLOW TO DEVELOP OVER EAST KENTUCKY DUE TO
PERSISTENT CLOUD COVER...BUT BREAKS ARE DEVELOPING IN THE CLOUDS AND
STORMS SHOULD RESPOND TO THIS AND THE APPROACHING COLD FRONT AND
IGNITE OVER THE NEXT COUPLE OF HOURS. HRRR HAS BEEN ADAMANT THAT
STORMS WILL BE SCATTERED AT BEST OVER OUR AREA...BUT LATEST RAP
MAKES A LITTLE MORE SENSE CONSIDERING THE ENVIRONMENT. IT DEVELOPS
CONVECTION OVERHEAD AND THEN TO OUR NORTHWEST AND WEST WITH THE
FRONT. THIS CONVECTION THEN MOVES OVER US INTO THE EVENING...WITH
THE UPPER CUMBERLAND REGION LOOKING TO TAKE THE BRUNT OF THE
ACTIVITY. FORECAST WAS TRENDED IN THIS DIRECTION AND DID LOWER POPS
A BIT...ESPECIALLY IN THE NORTH BASED ON MODEL DATA. WILL CONTINUE
TO ADVERTISE THE SEVERE THREAT THROUGH THE EVENING.
THE FRONT WILL HANG UP OVER SOUTHEAST KENTUCKY ON WEDNESDAY. CLOUD
COVER MAY BE SLOW TO ERODE AGAIN...BUT MODELS INDICATE STEEPENING
LAPSE RATES DEVELOPING DURING THE DAY WITH ADEQUATE CAPE TO POP OFF
AN ISOLATED SHOWER OR STORM JUST ABOUT ANYWHERE AS TEMPS RISE AGAIN
INTO THE 80S. THIS THREAT WILL END QUICKLY EARLY IN THE EVENING WITH
THE LOSS OF DAYTIME HEATING AND EXPECT DECREASING CLOUDS WEDNESDAY
NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 300 PM EDT TUE JUL 8 2014
THE MODELS WERE IN PRETTY GOOD AGREEMENT IN THE EXTENDED THIS TIME
AROUND. THE 12Z RUN OF THE ECMWF WAS COMING MUCH MORE INTO LINE WITH
THE GFS MODEL...WITH A DRY START TO THE PERIOD AS HIGH PRESSURE
GRADUALLY DRIFTS OFF TO THE SOUTHEAST TOWARD THE END OF THE WEEK. THE
CONSENSUS VIEW IS NOW FOR A VIGOROUS AREA OF UPPER LEVEL LOW PRESSURE
TO MOVE ACROSS THE UPPER GREAT LAKES SOUTHERN CANADA
AREA...PARTICULARLY OVER THE UPCOMING WEEKEND. THE TROUGH LOOKS TO BE
AT ITS MOST POTENT FROM SUNDAY ONWARD...AS IT DIPS SOUTH OUT OF
CANADA AND INTO THE NORTH CENTRAL CONUS TO BEGIN THE WORK WEEK NEXT
WEEK. THE BULK OF THE EXTENDED LOOKS TO BE DRY AT THIS POINT...WITH
THE ANTICIPATED PATTERN LENDING ITSELF TO MORE MOIST AND ACTIVE
PERIOD AND RAIN CHANCES FROM SUNDAY ONWARD. TEMPERATURES THROUGHOUT
THE PERIOD SHOULD BE AT OR SLIGHTLY BELOW NORMAL...WITH THE COOLER
DAY TIME HIGHS OCCURRING SUNDAY AND MONDAY AS CLOUD COVER AND
PRECIPITATION BEGIN OVERSPREADING THE AREA. THE START OF THE PERIOD
LOOKS TO BE MORE WARM AND HUMID.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 124 AM EDT WED JUL 9 2014
ISOLATED TO SCATTERED SHOWERS AND STORMS WILL WORK SOUTHEAST OVER THE
NEXT 2 TO 4 HOURS AND WILL LIKELY IMPACT THE TAF SITES. HAVE INCLUDED
AN HOUR WINDOW OF PREVAILING SHOWERS TO ACCOUNT FOR THIS ACTIVITY.
THE THREAT WILL EXIT TO THE SOUTHEAST BY 11Z. THEN VFR CONDITIONS
WILL PREVAIL THROUGH THE REMAINDER OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...ABE
LONG TERM...AR
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1009 PM CDT THU JUL 10 2014
.DISCUSSION...
A FEW STORMS CONTINUE TO LINGER THIS EVENING ALONG A WEAK BOUNDARY
DRAPED ACROSS OUR REGION FROM NEAR BROKEN BOW OK...TO MINDEN
LA...TO ALEXANDRIA. WHILE THE OVERALL TREND IS DIMINISHING...A FEW
OF STORMS COULD HOLD ON INTO THE WEE HOURS OF THE MORNING. THUS...HAVE
CONTINUED THE 20 POPS FROM THIS EVENING ON INTO THE LATTER HALF OF
THE OVERNIGHT PD. MADE SOME MINOR ADJUSTMENTS TO THE SKY GRIDS
BASED ON CURRENT CONDITIONS...BUT THE FCST IS ON TRACK OTHERWISE.
UPDATED PRODUCTS WILL BE OUT SHORTLY. /12/
&&
.PREV DISCUSSION... /ISSUED 743 PM CDT THU JUL 10 2014/
AVIATION...
WIDELY SCATTERED CONVECTION THIS EVENING ORIENTED ALONG A WEAK
BOUNDARY THAT EXTENDS FROM SOUTHEAST OKLAHOMA INTO SW AR AND NE
LA. THIS CONVECTION APPEARS TO HAVE CLEARED THE ELD/MLU TERMINALS
BUT THERE STILL A SMALL POSSIBILITY THEY COULD RETROGRADE INTO THE
TXK TERMINAL IN THE NEXT HOUR OR TWO. ANOTHER OUTFLOW BOUNDARY
FROM NW FLOW CONVECTION ACROSS SOUTHEAST OKLAHOMA IS DIVING
SOUTHWARD ATTM BUT THE HRRR DOES NOT DO MUCH WITH IT AFTER SUNSET
THIS EVENING.
FOR THE MOST PART...OTHER THAN ISOLATED CONVECTION AT THE ABOVE
MENTIONED LOCATIONS FOR THE NEXT 2 TO 4 HOURS...EXPECTING MOSTLY
VFR CONDITIONS TO PREVAIL OVERNIGHT THROUGH THE DAY FRIDAY.
13
PREV DISCUSSION... /ISSUED 307 PM CDT THU JUL 10 2014/
DISCUSSION...
BROAD UPPER LEVEL RIDGING OVER CENTRAL TX...ALLOWING SLIGHTLY
INCREASED CONVECTION ACROSS PERIPHERY OF RIDGE AS SHORT WAVES
ROTATE THRU IT. IN ADDITION..SEA BREEZE ACTIVITY DEVELOPED EARLY
THIS AFTN..BUT NOW STILL REMAINING SOUTH OF CWA. WILL PLACE ENTIRE
AREA IN SLIGHT CHANCE FOR EARLY EVENING CONVECTION...WITH
ASSUMPTION THAT ANY SEA BREEZE ACTIVITY THAT REACHES AREA WILL
DIMINISH BEFORE SUNSET. HOWEVER...THE NW UPPER LVL FLOW ACTIVITY
OVER SW AR...SE OK...AND NORTHCENTRAL LA...MAY PERSIST THRU THE
EVE...WITH ADDITIONAL CLUSTER OF TSTMS OVER NE OK...HEADED THIS
WAY. AS UPPER RIDGE BUILDS INTO AREA AND MID LVL DRYING BEGINS
TAKING PLACE ON FRIDAY...HAVE REMOVED POPS THRU WEEKEND...EXCEPT
FOR POSSIBLE VERY LIMITED SEA BREEZE ACTIVITY SOUTH CWA. AFTN
TEMPS WILL BEGIN TO CLIMB INTO MID TO UPPER 90S...AND HEAT
ADVISORY CRITERIA MAY BE APPROACHED. MODELS HAVE BEEN CONSISTENTLY
BRINGING A WEAK COOL FRONT INTO AREA FROM THE NORTH...PUSHED SWD
BY HIGH PRESSURE SINKING INTO UPPER MIDWEST...BY TUESDAY. FOR NOW
WILL GO NEAR 30 PERCENT POPS NEAR BOUNDARY...ALTHOUGH THIS
COVERAGE MAY NEED TO BE RAISED BY LATER IN WEEKEND ONCE FRONTAL
ACTIVITY TRENDS ARE NOTED TO THE NORTH OF AREA./VII/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 74 95 73 97 75 / 10 10 10 10 10
MLU 72 92 76 96 73 / 20 20 10 10 10
DEQ 72 94 72 97 70 / 20 20 10 10 10
TXK 74 94 74 96 74 / 20 10 10 10 10
ELD 72 92 74 96 72 / 20 20 10 10 10
TYR 73 95 72 96 75 / 10 10 10 10 10
GGG 73 95 72 95 75 / 10 10 10 10 10
LFK 73 95 73 95 74 / 10 10 10 20 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
12/99
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
743 PM CDT THU JUL 10 2014
.AVIATION...
WIDELY SCATTERED CONVECTION THIS EVENING ORIENTED ALONG A WEAK
BOUNDARY THAT EXTENDS FROM SOUTHEAST OKLAHOMA INTO SW AR AND NE
LA. THIS CONVECTION APPEARS TO HAVE CLEARED THE ELD/MLU TERMINALS
BUT THERE STILL A SMALL POSSIBILITY THEY COULD RETROGRADE INTO THE
TXK TERMINAL IN THE NEXT HOUR OR TWO. ANOTHER OUTFLOW BOUNDARY
FROM NW FLOW CONVECTION ACROSS SOUTHEAST OKLAHOMA IS DIVING
SOUTHWARD ATTM BUT THE HRRR DOES NOT DO MUCH WITH IT AFTER SUNSET
THIS EVENING.
FOR THE MOST PART...OTHER THAN ISOLATED CONVECTION AT THE ABOVE
MENTIONED LOCATIONS FOR THE NEXT 2 TO 4 HOURS...EXPECTING MOSTLY
VFR CONDITIONS TO PREVAIL OVERNIGHT THROUGH THE DAY FRIDAY.
13
&&
.PREV DISCUSSION... /ISSUED 307 PM CDT THU JUL 10 2014/
DISCUSSION...
BROAD UPPER LEVEL RIDGING OVER CENTRAL TX...ALLOWING SLIGHTLY
INCREASED CONVECTION ACROSS PERIPHERY OF RIDGE AS SHORT WAVES
ROTATE THRU IT. IN ADDITION..SEA BREEZE ACTIVITY DEVELOPED EARLY
THIS AFTN..BUT NOW STILL REMAINING SOUTH OF CWA. WILL PLACE ENTIRE
AREA IN SLIGHT CHANCE FOR EARLY EVENING CONVECTION...WITH
ASSUMPTION THAT ANY SEA BREEZE ACTIVITY THAT REACHES AREA WILL
DIMINISH BEFORE SUNSET. HOWEVER...THE NW UPPER LVL FLOW ACTIVITY
OVER SW AR...SE OK...AND NORTHCENTRAL LA...MAY PERSIST THRU THE
EVE...WITH ADDITIONAL CLUSTER OF TSTMS OVER NE OK...HEADED THIS
WAY. AS UPPER RIDGE BUILDS INTO AREA AND MID LVL DRYING BEGINS
TAKING PLACE ON FRIDAY...HAVE REMOVED POPS THRU WEEKEND...EXCEPT
FOR POSSIBLE VERY LIMITED SEA BREEZE ACTIVITY SOUTH CWA. AFTN
TEMPS WILL BEGIN TO CLIMB INTO MID TO UPPER 90S...AND HEAT
ADVISORY CRITERIA MAY BE APPROACHED. MODELS HAVE BEEN CONSISTENTLY
BRINGING A WEAK COOL FRONT INTO AREA FROM THE NORTH...PUSHED SWD
BY HIGH PRESSURE SINKING INTO UPPER MIDWEST...BY TUESDAY. FOR NOW
WILL GO NEAR 30 PERCENT POPS NEAR BOUNDARY...ALTHOUGH THIS
COVERAGE MAY NEED TO BE RAISED BY LATER IN WEEKEND ONCE FRONTAL
ACTIVITY TRENDS ARE NOTED TO THE NORTH OF AREA./VII/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 74 95 73 97 75 / 20 10 10 10 10
MLU 72 92 76 96 73 / 20 20 10 10 10
DEQ 72 94 72 97 70 / 20 20 10 10 10
TXK 74 94 74 96 74 / 20 10 10 10 10
ELD 72 92 74 96 72 / 20 20 10 10 10
TYR 73 95 72 96 75 / 20 10 10 10 10
GGG 73 95 72 95 75 / 20 10 10 10 10
LFK 73 95 73 95 74 / 20 10 10 20 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
13
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1245 PM CDT WED JUL 9 2014
.DISCUSSION...
09/18Z TAF ISSUANCE.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACRS THE AREA WITH SOME SCT SHRA/TSRA
DEVELOPING NEAR THE ACADIANA TERMINALS. BEST CHANCES FOR
CONVECTION WILL REMAIN ACRS ERN PORTIONS OF THE AREA WHERE
DEEPER MOISTURE INTERACTS WITH A PASSING DISTURBANCE. AT THIS
TIME...KEPT VC MENTION IN LA TERMINALS THROUGH THIS AFTN AND
EVENING...WITH THE POTENTIAL FOR AMENDING WITH TEMPO GROUPS AS
CONVECTION BECOMES MORE CONSOLIDATED. ACTIVITY SHOULD WIND DOWN
THIS EVENING. VFR AND LT VRBL OR SWLY WINDS TO PREVAIL THROUGH
THE PERIOD. 24
&&
.PREV DISCUSSION... /ISSUED 1053 AM CDT WED JUL 9 2014/
DISCUSSION...
REGIONAL 88DS SHOW PLENTIFUL CONVECTION ASSOCIATED WITH A PASSING
DISTURBANCE ALOFT SKIRTING THE NERN ZONES ATTM. MEANWHILE A FEW
SHOWERS/STORMS HAVE POPPED UP IN AREA OF ENHANCED MOISTURE OVER
THE SERN ZONES. ALL THIS GOES ALONG WELL WITH INHERITED
GRIDS/ZONES OTHER THAN MAYBE DEVELOPING A COUPLE OF HOURS QUICKER
THAN PREVIOUSLY THOUGHT...THEREFORE SIMPLY PUSHED AFTERNOON POPS
UP A BIT TO ACCOUNT. HOWEVER WILL CONTINUE TO MONITOR RADARS IN
CASE POPS NEED TO BE INCREASED...ESPECIALLY ACROSS ACADIANA.
ELSEWHERE JUST VERY MINOR TWEAKS WERE MADE TO GRIDS/ZONES.
UPDATE OUT SHORTLY.
25
PREV DISCUSSION... /ISSUED 705 AM CDT WED JUL 9 2014/
AVIATION UPDATE...REGARDING 12Z TAF ISSUANCE. LIMITED NOCTURNAL
CONVECTIVE ACTIVITY OVER THE NEAR COASTAL WATERS AND ACADIANA THIS
MORNING COMPARED TO YESTERDAY. BEGINNING TO SEE SOME SHOWER
DEVELOPMENT OVER CENTRAL LOUISIANA ASSOCIATED WITH WEAK SHORTWAVE
ENERGY ADVANCING SOUTHEAST. THIS AHEAD OF A MORE VIGOROUS COMPLEX
OVER ARKANSAS. WITH THE EXCEPTION OF BPT...WILL CARRY ALL OTHER
TERMINALS WITH VCTS THROUGH TODAY. APPEARS THE WESTERN PORTION
OF THE AREA MAY BE TOO LIMITED FOR DEVELOPMENT. THUNDERSTORMS WILL
BE TRIGGERED BY INCOMING OUTFLOWS/DISTURBANCES FROM THE
NORTH...AND A DEVELOPING BUT WEAK SEA BREEZE. END ANY FURTHER
PRECIP WITH THE SETTING SUN. STILL ANTICIPATING VFR TO PREVAIL
AGAIN TODAY WHILE WINDS REMAIN LIGHT.
MARCOTTE
PREV DISCUSSION... /ISSUED 349 AM CDT WED JUL 9 2014/
DISCUSSION...
LOTS TO LOOK AT THIS MORNING STARTING ALOFT...LARGE CIRRUS SHIELD
ON THE IR SATELLITE THIS MORNING ADVANCING SOUTHWARD IN THE 500MB
NORTHERLY FLOW ALOFT. THIS CLOUD COVER ORIGINATED FROM CONVECTION
FIRING OFF ON A COOL FRONT WHICH WAS DRAPED ACROSS OKLAHOMA AND
ARKANSAS. WENT AHEAD AND ADDED SOME HIGH CLOUDS IN THE DIGITAL
GRIDS TO SHOW THIS ADVANCING CLOUD SHIELD WHICH SHOULD THIN OUT
LATER THIS MORNING.
ALSO THIS MORNING...LCH RADAR SHOWED CONVECTION FIRING OFF THE COASTAL
WATERS BETWEEN CAMERON AND THE LOWER ATCHAFALAYA RIVER. THIS ACTIVITY
WAS ASSOCIATED WITH DEEPER MOISTURE WITH AREA SOUNDING PROFILES UP
OVER 2 INCHES OF PRECIPITABLE WATER. MOST OF THIS ACTIVITY WAS
DISSIPATING AS IT REACHED LAND.
TODAY EXPECT HIGH CLOUDS TO SPREAD SOUTHWARD THIS MORNING AND THIN
OUT SOME AS IT MAKES IT WAY DOWN INTO THE I-10 CORRIDOR REGION. AS
LAND HEATS UP ALONG THE COASTAL AREAS....WILL LIKELY SEE SOME
CONVECTION BEGIN TO FIRE ON LAND MOSTLY ACROSS THE SOUTHEAST PART
OF OUR AREA. HOWEVER...BOTH THE WRF LOCAL MODEL AND THE HRRR SHOW
AT LEAST SOME ACTIVITY SPREADING NORTHWARD TO SOME OF THE I-10
CORRIDOR AREAS OF LOUISIANA...TO A LESSER DEGREE ACROSS SOUTHEAST
TEXAS. WILL GO WITH LOWEST POPS INLAND SOUTHEAST TEXAS...HOWEVER
MOSTLY 20 PERCENT EVERYWHERE EXCEPT ACROSS SOUTH CENTRAL LOUISIANA
WHERE HIGHER POPS WILL BE FOUND.
THE FRONTAL BOUNDARY MAY NOT GET FURTHER THAN NORTHERN LOUISIANA BEFORE
WASHING OUT OVER THE NEXT COUPLE OF DAYS. GENERALLY OUR REGION WILL
STAY IN A COL BETWEEN LOW PRESSURE NORTHEAST AND SOUTHWEST OF
US...AND HIGH PRESSURE NORTHWEST AND SOUTHEAST OF US.
IN THE MIDDLE OF THIS COL...PRETTY MUCH EXPECT DAYTIME HEATING...
SEABREEZE...AND OUTFLOW BOUNDARIES TO DISTRIBUTE THE RAINFALL
THROUGH FRIDAY. AS WE GET INTO THE WEEKEND...MAY BEGIN TO SEE HIGH
PRESSURE FROM NORTH TEXAS BUILD SOUTHEAST INTO OUR AREA. SO
EXPECT...LOWER CHANCES OF RAIN ESPECIALLY SUNDAY THROUGH TUESDAY.
FOR MOST OF US...HOT DAYS AND WARM NIGHTS WILL CONTINUE FOR THE
NEXT 7 DAYS. SOME MAY GET LUCKY ENOUGH TO GET SOME RAIN COOLED
AIR...BUT MOST WILL LIKELY JUST STAY ON THE DRIER SIDE AS WE GET
INTO THE DOG DAYS OF SUMMER.
MARINE...
HIGH PRESSURE RIDGING ACROSS THE NORTHWEST GULF OF MEXICO WILL KEEP
SOUTHERLY FLOW ON THE LOWER END OF THE SCALE THROUGH THE 5 DAY FORECAST
PERIOD. WAVE HEIGHTS WILL GENERALLY FOLLOW THIS TREND AS WELL WITH
LOWER HEIGHTS. LATE NIGHT CONVECTION 20NM TO 60 NM OFFSHORE WILL
CONTINUE BUT MOSTLY ALONG AND EAST OF CAMERON LOUISIANA.
06
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 92 74 91 74 / 30 10 30 10
KBPT 92 75 91 75 / 20 10 30 10
KAEX 94 74 93 73 / 20 10 30 10
KLFT 92 75 91 74 / 30 10 40 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1053 AM CDT WED JUL 9 2014
.DISCUSSION...
REGIONAL 88DS SHOW PLENTIFUL CONVECTION ASSOCIATED WITH A PASSING
DISTURBANCE ALOFT SKIRTING THE NERN ZONES ATTM. MEANWHILE A FEW
SHOWERS/STORMS HAVE POPPED UP IN AREA OF ENHANCED MOISTURE OVER
THE SERN ZONES. ALL THIS GOES ALONG WELL WITH INHERITED
GRIDS/ZONES OTHER THAN MAYBE DEVELOPING A COUPLE OF HOURS QUICKER
THAN PREVIOUSLY THOUGHT...THEREFORE SIMPLY PUSHED AFTERNOON POPS
UP A BIT TO ACCOUNT. HOWEVER WILL CONTINUE TO MONITOR RADARS IN
CASE POPS NEED TO BE INCREASED...ESPECIALLY ACROSS ACADIANA.
ELSEWHERE JUST VERY MINOR TWEAKS WERE MADE TO GRIDS/ZONES.
UPDATE OUT SHORTLY.
25
&&
.PREV DISCUSSION... /ISSUED 705 AM CDT WED JUL 9 2014/
AVIATION UPDATE...REGARDING 12Z TAF ISSUANCE. LIMITED NOCTURNAL
CONVECTIVE ACTIVITY OVER THE NEAR COASTAL WATERS AND ACADIANA THIS
MORNING COMPARED TO YESTERDAY. BEGINNING TO SEE SOME SHOWER
DEVELOPMENT OVER CENTRAL LOUISIANA ASSOCIATED WITH WEAK SHORTWAVE
ENERGY ADVANCING SOUTHEAST. THIS AHEAD OF A MORE VIGOROUS COMPLEX
OVER ARKANSAS. WITH THE EXCEPTION OF BPT...WILL CARRY ALL OTHER
TERMINALS WITH VCTS THROUGH TODAY. APPEARS THE WESTERN PORTION
OF THE AREA MAY BE TOO LIMITED FOR DEVELOPMENT. THUNDERSTORMS WILL
BE TRIGGERED BY INCOMING OUTFLOWS/DISTURBANCES FROM THE
NORTH...AND A DEVELOPING BUT WEAK SEA BREEZE. END ANY FURTHER
PRECIP WITH THE SETTING SUN. STILL ANTICIPATING VFR TO PREVAIL
AGAIN TODAY WHILE WINDS REMAIN LIGHT.
MARCOTTE
PREV DISCUSSION... /ISSUED 349 AM CDT WED JUL 9 2014/
DISCUSSION...
LOTS TO LOOK AT THIS MORNING STARTING ALOFT...LARGE CIRRUS SHIELD
ON THE IR SATELLITE THIS MORNING ADVANCING SOUTHWARD IN THE 500MB
NORTHERLY FLOW ALOFT. THIS CLOUD COVER ORIGINATED FROM CONVECTION
FIRING OFF ON A COOL FRONT WHICH WAS DRAPED ACROSS OKLAHOMA AND
ARKANSAS. WENT AHEAD AND ADDED SOME HIGH CLOUDS IN THE DIGITAL
GRIDS TO SHOW THIS ADVANCING CLOUD SHIELD WHICH SHOULD THIN OUT
LATER THIS MORNING.
ALSO THIS MORNING...LCH RADAR SHOWED CONVECTION FIRING OFF THE COASTAL
WATERS BETWEEN CAMERON AND THE LOWER ATCHAFALAYA RIVER. THIS ACTIVITY
WAS ASSOCIATED WITH DEEPER MOISTURE WITH AREA SOUNDING PROFILES UP
OVER 2 INCHES OF PRECIPITABLE WATER. MOST OF THIS ACTIVITY WAS
DISSIPATING AS IT REACHED LAND.
TODAY EXPECT HIGH CLOUDS TO SPREAD SOUTHWARD THIS MORNING AND THIN
OUT SOME AS IT MAKES IT WAY DOWN INTO THE I-10 CORRIDOR REGION. AS
LAND HEATS UP ALONG THE COASTAL AREAS....WILL LIKELY SEE SOME
CONVECTION BEGIN TO FIRE ON LAND MOSTLY ACROSS THE SOUTHEAST PART
OF OUR AREA. HOWEVER...BOTH THE WRF LOCAL MODEL AND THE HRRR SHOW
AT LEAST SOME ACTIVITY SPREADING NORTHWARD TO SOME OF THE I-10
CORRIDOR AREAS OF LOUISIANA...TO A LESSER DEGREE ACROSS SOUTHEAST
TEXAS. WILL GO WITH LOWEST POPS INLAND SOUTHEAST TEXAS...HOWEVER
MOSTLY 20 PERCENT EVERYWHERE EXCEPT ACROSS SOUTH CENTRAL LOUISIANA
WHERE HIGHER POPS WILL BE FOUND.
THE FRONTAL BOUNDARY MAY NOT GET FURTHER THAN NORTHERN LOUISIANA BEFORE
WASHING OUT OVER THE NEXT COUPLE OF DAYS. GENERALLY OUR REGION WILL
STAY IN A COL BETWEEN LOW PRESSURE NORTHEAST AND SOUTHWEST OF
US...AND HIGH PRESSURE NORTHWEST AND SOUTHEAST OF US.
IN THE MIDDLE OF THIS COL...PRETTY MUCH EXPECT DAYTIME HEATING...
SEABREEZE...AND OUTFLOW BOUNDARIES TO DISTRIBUTE THE RAINFALL
THROUGH FRIDAY. AS WE GET INTO THE WEEKEND...MAY BEGIN TO SEE HIGH
PRESSURE FROM NORTH TEXAS BUILD SOUTHEAST INTO OUR AREA. SO
EXPECT...LOWER CHANCES OF RAIN ESPECIALLY SUNDAY THROUGH TUESDAY.
FOR MOST OF US...HOT DAYS AND WARM NIGHTS WILL CONTINUE FOR THE
NEXT 7 DAYS. SOME MAY GET LUCKY ENOUGH TO GET SOME RAIN COOLED
AIR...BUT MOST WILL LIKELY JUST STAY ON THE DRIER SIDE AS WE GET
INTO THE DOG DAYS OF SUMMER.
MARINE...
HIGH PRESSURE RIDGING ACROSS THE NORTHWEST GULF OF MEXICO WILL KEEP
SOUTHERLY FLOW ON THE LOWER END OF THE SCALE THROUGH THE 5 DAY FORECAST
PERIOD. WAVE HEIGHTS WILL GENERALLY FOLLOW THIS TREND AS WELL WITH
LOWER HEIGHTS. LATE NIGHT CONVECTION 20NM TO 60 NM OFFSHORE WILL
CONTINUE BUT MOSTLY ALONG AND EAST OF CAMERON LOUISIANA.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 92 75 90 75 93 / 20 10 30 10 20
KBPT 92 75 91 75 92 / 20 10 30 10 20
KAEX 94 74 93 73 95 / 20 10 30 10 20
KLFT 92 74 91 74 93 / 30 10 40 10 20
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.LAKECHARLES.GOV
WWW.TWITTER.COM/NWSLAKECHARLES
WWW.YOUTUBE.COM/NWSLAKECHARLES
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
705 AM CDT WED JUL 9 2014
.AVIATION UPDATE...REGARDING 12Z TAF ISSUANCE. LIMITED NOCTURNAL
CONVECTIVE ACTIVITY OVER THE NEAR COASTAL WATERS AND ACADIANA THIS
MORNING COMPARED TO YESTERDAY. BEGINNING TO SEE SOME SHOWER
DEVELOPMENT OVER CENTRAL LOUISIANA ASSOCIATED WITH WEAK SHORTWAVE
ENERGY ADVANCING SOUTHEAST. THIS AHEAD OF A MORE VIGOROUS COMPLEX
OVER ARKANSAS. WITH THE EXCEPTION OF BPT...WILL CARRY ALL OTHER
TERMINALS WITH VCTS THROUGH TODAY. APPEARS THE WESTERN PORTION
OF THE AREA MAY BE TOO LIMITED FOR DEVELOPMENT. THUNDERSTORMS WILL
BE TRIGGERED BY INCOMING OUTFLOWS/DISTURBANCES FROM THE
NORTH...AND A DEVELOPING BUT WEAK SEA BREEZE. END ANY FURTHER
PRECIP WITH THE SETTING SUN. STILL ANTICIPATING VFR TO PREVAIL
AGAIN TODAY WHILE WINDS REMAIN LIGHT.
&&
MARCOTTE
&&
.PREV DISCUSSION... /ISSUED 349 AM CDT WED JUL 9 2014/
DISCUSSION...
LOTS TO LOOK AT THIS MORNING STARTING ALOFT...LARGE CIRRUS SHIELD
ON THE IR SATELLITE THIS MORNING ADVANCING SOUTHWARD IN THE 500MB
NORTHERLY FLOW ALOFT. THIS CLOUD COVER ORIGINATED FROM CONVECTION
FIRING OFF ON A COOL FRONT WHICH WAS DRAPED ACROSS OKLAHOMA AND
ARKANSAS. WENT AHEAD AND ADDED SOME HIGH CLOUDS IN THE DIGITAL
GRIDS TO SHOW THIS ADVANCING CLOUD SHIELD WHICH SHOULD THIN OUT
LATER THIS MORNING.
ALSO THIS MORNING...LCH RADAR SHOWED CONVECTION FIRING OFF THE COASTAL
WATERS BETWEEN CAMERON AND THE LOWER ATCHAFALAYA RIVER. THIS ACTIVITY
WAS ASSOCIATED WITH DEEPER MOISTURE WITH AREA SOUNDING PROFILES UP
OVER 2 INCHES OF PRECIPITABLE WATER. MOST OF THIS ACTIVITY WAS
DISSIPATING AS IT REACHED LAND.
TODAY EXPECT HIGH CLOUDS TO SPREAD SOUTHWARD THIS MORNING AND THIN
OUT SOME AS IT MAKES IT WAY DOWN INTO THE I-10 CORRIDOR REGION. AS
LAND HEATS UP ALONG THE COASTAL AREAS....WILL LIKELY SEE SOME
CONVECTION BEGIN TO FIRE ON LAND MOSTLY ACROSS THE SOUTHEAST PART
OF OUR AREA. HOWEVER...BOTH THE WRF LOCAL MODEL AND THE HRRR SHOW
AT LEAST SOME ACTIVITY SPREADING NORTHWARD TO SOME OF THE I-10
CORRIDOR AREAS OF LOUISIANA...TO A LESSER DEGREE ACROSS SOUTHEAST
TEXAS. WILL GO WITH LOWEST POPS INLAND SOUTHEAST TEXAS...HOWEVER
MOSTLY 20 PERCENT EVERYWHERE EXCEPT ACROSS SOUTH CENTRAL LOUISIANA
WHERE HIGHER POPS WILL BE FOUND.
THE FRONTAL BOUNDARY MAY NOT GET FURTHER THAN NORTHERN LOUISIANA BEFORE
WASHING OUT OVER THE NEXT COUPLE OF DAYS. GENERALLY OUR REGION WILL
STAY IN A COL BETWEEN LOW PRESSURE NORTHEAST AND SOUTHWEST OF
US...AND HIGH PRESSURE NORTHWEST AND SOUTHEAST OF US.
IN THE MIDDLE OF THIS COL...PRETTY MUCH EXPECT DAYTIME HEATING...
SEABREEZE...AND OUTFLOW BOUNDARIES TO DISTRIBUTE THE RAINFALL
THROUGH FRIDAY. AS WE GET INTO THE WEEKEND...MAY BEGIN TO SEE HIGH
PRESSURE FROM NORTH TEXAS BUILD SOUTHEAST INTO OUR AREA. SO
EXPECT...LOWER CHANCES OF RAIN ESPECIALLY SUNDAY THROUGH TUESDAY.
FOR MOST OF US...HOT DAYS AND WARM NIGHTS WILL CONTINUE FOR THE
NEXT 7 DAYS. SOME MAY GET LUCKY ENOUGH TO GET SOME RAIN COOLED
AIR...BUT MOST WILL LIKELY JUST STAY ON THE DRIER SIDE AS WE GET
INTO THE DOG DAYS OF SUMMER.
MARINE...
HIGH PRESSURE RIDGING ACROSS THE NORTHWEST GULF OF MEXICO WILL KEEP
SOUTHERLY FLOW ON THE LOWER END OF THE SCALE THROUGH THE 5 DAY FORECAST
PERIOD. WAVE HEIGHTS WILL GENERALLY FOLLOW THIS TREND AS WELL WITH
LOWER HEIGHTS. LATE NIGHT CONVECTION 20NM TO 60 NM OFFSHORE WILL
CONTINUE BUT MOSTLY ALONG AND EAST OF CAMERON LOUISIANA.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 92 75 90 75 93 / 20 10 30 10 20
KBPT 92 75 91 75 92 / 20 10 30 10 20
KAEX 94 74 93 73 95 / 20 10 30 10 20
KLFT 92 74 91 74 93 / 30 10 40 10 20
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
349 AM CDT WED JUL 9 2014
.DISCUSSION...
LOTS TO LOOK AT THIS MORNING STARTING ALOFT...LARGE CIRRUS SHIELD
ON THE IR SATELLITE THIS MORNING ADVANCING SOUTHWARD IN THE 500MB
NORTHERLY FLOW ALOFT. THIS CLOUD COVER ORIGINATED FROM CONVECTION
FIRING OFF ON A COOL FRONT WHICH WAS DRAPED ACROSS OKLAHOMA AND
ARKANSAS. WENT AHEAD AND ADDED SOME HIGH CLOUDS IN THE DIGITAL
GRIDS TO SHOW THIS ADVANCING CLOUD SHIELD WHICH SHOULD THIN OUT
LATER THIS MORNING.
ALSO THIS MORNING...LCH RADAR SHOWED CONVECTION FIRING OFF THE COASTAL
WATERS BETWEEN CAMERON AND THE LOWER ATCHAFALAYA RIVER. THIS ACTIVITY
WAS ASSOCIATED WITH DEEPER MOISTURE WITH AREA SOUNDING PROFILES UP
OVER 2 INCHES OF PRECIPITABLE WATER. MOST OF THIS ACTIVITY WAS
DISSIPATING AS IT REACHED LAND.
TODAY EXPECT HIGH CLOUDS TO SPREAD SOUTHWARD THIS MORNING AND THIN
OUT SOME AS IT MAKES IT WAY DOWN INTO THE I-10 CORRIDOR REGION. AS
LAND HEATS UP ALONG THE COASTAL AREAS....WILL LIKELY SEE SOME
CONVECTION BEGIN TO FIRE ON LAND MOSTLY ACROSS THE SOUTHEAST PART
OF OUR AREA. HOWEVER...BOTH THE WRF LOCAL MODEL AND THE HRRR SHOW
AT LEAST SOME ACTIVITY SPREADING NORTHWARD TO SOME OF THE I-10
CORRIDOR AREAS OF LOUISIANA...TO A LESSER DEGREE ACROSS SOUTHEAST
TEXAS. WILL GO WITH LOWEST POPS INLAND SOUTHEAST TEXAS...HOWEVER
MOSTLY 20 PERCENT EVERYWHERE EXCEPT ACROSS SOUTH CENTRAL LOUISIANA
WHERE HIGHER POPS WILL BE FOUND.
THE FRONTAL BOUNDARY MAY NOT GET FURTHER THAN NORTHERN LOUISIANA BEFORE
WASHING OUT OVER THE NEXT COUPLE OF DAYS. GENERALLY OUR REGION WILL
STAY IN A COL BETWEEN LOW PRESSURE NORTHEAST AND SOUTHWEST OF
US...AND HIGH PRESSURE NORTHWEST AND SOUTHEAST OF US.
IN THE MIDDLE OF THIS COL...PRETTY MUCH EXPECT DAYTIME HEATING...
SEABREEZE...AND OUTFLOW BOUNDARIES TO DISTRIBUTE THE RAINFALL
THROUGH FRIDAY. AS WE GET INTO THE WEEKEND...MAY BEGIN TO SEE HIGH
PRESSURE FROM NORTH TEXAS BUILD SOUTHEAST INTO OUR AREA. SO
EXPECT...LOWER CHANCES OF RAIN ESPECIALLY SUNDAY THROUGH TUESDAY.
FOR MOST OF US...HOT DAYS AND WARM NIGHTS WILL CONTINUE FOR THE
NEXT 7 DAYS. SOME MAY GET LUCKY ENOUGH TO GET SOME RAIN COOLED
AIR...BUT MOST WILL LIKELY JUST STAY ON THE DRIER SIDE AS WE GET
INTO THE DOG DAYS OF SUMMER.
&&
.MARINE...
HIGH PRESSURE RIDGING ACROSS THE NORTHWEST GULF OF MEXICO WILL KEEP
SOUTHERLY FLOW ON THE LOWER END OF THE SCALE THROUGH THE 5 DAY FORECAST
PERIOD. WAVE HEIGHTS WILL GENERALLY FOLLOW THIS TREND AS WELL WITH
LOWER HEIGHTS. LATE NIGHT CONVECTION 20NM TO 60 NM OFFSHORE WILL
CONTINUE BUT MOSTLY ALONG AND EAST OF CAMERON LOUISIANA.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 92 75 90 75 / 20 10 30 10
KBPT 92 75 91 75 / 20 10 30 10
KAEX 94 74 93 73 / 20 10 30 10
KLFT 92 74 91 74 / 30 10 40 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE...06
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1209 AM CDT WED JUL 9 2014
.AVIATION...
VFR CONDITIONS ARE EXPECTED FOR NEXT 24 HOURS EXCEPT DURING BRIEF
PERIODS OF TSRA AFTER 16Z. KHUM MAY BE IMPACTED BY SHRA/TSRA PRIOR
TO 14Z AS COASTAL CONVECTION LINGERS ALONG THE TERREBONNE PARISH
COAST. CONVECTIVE COVERAGE SHOULD WARRANT PROB30 GROUPINGS AT THIS
TIME. 24/RR
&&
.PREV DISCUSSION... /ISSUED 331 PM CDT TUE JUL 8 2014/
DISCUSSION...
AN UPPER LEVEL TROUGH IS IN THE PROCESS OF DIGGING SOUTHWARD ACROSS
THE GREAT LAKES AND OHIO RIVER VALLEY TODAY AND WILL CONTINUE TO
PROTRUDE FURTHER SOUTH AS IT PROGRESSES EAST. AT THE SAME TIME...
MOISTURE HAS BEEN BACK ON THE INCREASE IN THE MID AND UPPER LEVELS.
THIS MORNING/S AT LIX SHOWED A PRECIP WATER VALUE OF NEAR 1.5 INCHES
AND MODEL SOUNDINGS INDICATE THAT THIS VALUE COULD BE NEAR 2 INCHES
BY THE 00Z FLIGHT. SO ITS NO SURPRISE THAT QUITE A BIT OF CONVECTION
HAS DEVELOPED TODAY. THE HRRR HAS DONE A PRETTY DECENT JOB OF
INITIALIZING AND KEEPING UP WITH THE CURRENT RADAR TRENDS. ITS
DEPICTION OF DIMINISHING ACTIVITY BY SUNSET AGREES WELL WITH TYPICAL
EXPECTATIONS OF STORM DISSIPATION WITH LOSS OF DAYTIME HEATING.
A WEAK COLD FRONT ASSOCIATED WITH THIS UPPER LEVEL TROUGH WILL
GRADUALLY SAG CLOSER AND CLOSER TO THE AREA AS WE APPROACH THE
WEEKEND. IT APPEARS THAT THE BOUNDARY WILL EVENTUALLY REACH THE
CWA BUT WILL BE IN A NEARLY INDISCERNIBLE STATE. LOCAL WEATHER
CONDITIONS FROM TODAY THROUGH THE WEEKEND WILL NOT BE VERY DIFFERENT
FROM DAY TO DAY. DAYTIME POPS SHOULD GENERALLY BE AROUND 30-50
PERCENT WITH A PEAK OF 60 PERCENT ON THURSDAY. NOCTURNAL OFFSHORE
SHOWERS POSSIBLE AS WELL. TEMPERATURES THROUGH THIS PERIOD WILL BE
NEAR NORMAL.
MEFFER
AVIATION...
MOISTURE RETURN HAS TRIGGERED SCATTERED CONVECTION THAT CONTINUES TO
DEVELOP THIS AFTERNOON. WHILE MOST TERMINALS ARE VFR...CONVECTION
WILL PRODUCE BRIEF IFR CONDITIONS AS THEY AFFECT TERMINALS. CARRYING
VCTS WITH TEMPO IFR AS APPROPRIATE OVER THE NEXT 3-4 HOURS.
CONVECTION SHOULD DIMINISH AS WE APPROACH SUNSET. VFR CONDITIONS
WILL BE THE RULE OVERNIGHT...WITH CONVECTIVE DEVELOPMENT AGAIN
ANTICIPATED ON WEDNESDAY BY LATE MORNING TO EARLY AFTERNOON. 35
MARINE...
A BRIEF NOCTURNAL MAX OF 10 TO 15 KNOTS IN THE NEARSHORE WATERS OF
LA AND MS ARE EXPECTED TONIGHT AND TOMORROW NIGHT AS A WEAK SURFACE
TROUGH TO THE NORTH TIGHTENS THE PRESSURE GRADIENT. OTHERWISE...
RELATIVELY LIGHT WIND AND WAVE CONDITIONS ARE EXPECTED TO PREVAIL
THROUGH MOST OF THE UPCOMING WEEK DUE TO A RIDGE OF HIGH PRESSURE
OVER THE REGION. SCATTERED CONVECTION WILL CONTINUE TO BE A THREAT
THROUGH THE FORECAST PERIOD. 35
DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...NONE.
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 TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 71 92 72 93 / 20 60 20 40
BTR 73 92 74 93 / 10 50 20 40
ASD 74 92 75 93 / 20 60 20 40
MSY 76 91 77 92 / 10 50 20 40
GPT 77 91 76 93 / 20 50 20 40
PQL 73 91 74 93 / 30 50 20 40
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1120 PM CDT TUE JUL 8 2014
.AVIATION...
CONVECTION HAS MADE SLOW BUT DESCENT PROGRESS THROUGH CENTRAL
ARKANSAS LATE THIS EVENING AND IS NOT TOO FAR AWAY FROM EFFECTING
THE TXK/ELD TERMINALS.
DIFFICULT TERMINAL FORECAST TO SAY THE LEAST AS THE CONVECTION HAS
SHOWN A WEAKENING TREND OVER THE LAST SEVERAL HOURS AS THE COLD
POOL HAS OUT RUN THE TRUE COLD FRONT WHICH WAS STILL LOCATED
ACROSS SOUTHERN OKLAHOMA INTO NORTHERN ARKANSAS. AN EXTRAPOLATION
OF THE COLD POOL SUGGESTS THAT CONVECTION COULD BE INTO THE
TXK/ELD TERMINALS BY 08Z IF THE CONVECTION CAN SURVIVE AS IT MOVES
SOUTH AND EAST.
FEEL LIKE THE BEST OPPORTUNITY TO GET CONVECTION CLOSER TO THE
SHV/MLU TERMINALS WILL BE AFTER SUNRISE...PERHAPS A LITTLE EARLIER
AT THE MLU TERMINAL AND FOR THAT REASON...HAVE ADDED VCTS TO THE
MLU TERMINAL DURING THE MID MORNING HOURS ON WED AND KEPT MENTION
OUT OF THE SHV TERMINAL UNTIL AFTERNOON. HEATING AND REMNANT
BOUNDARIES WILL BE KEY TO SCATTERED CONVECTION DURING THE
AFTERNOON ON WED AND WOULD NOT BE SURPRISED TO SEE VCTS AT THE
TYR/GGG TERMINALS AS WELL DURING THE LATE AFTERNOON HOURS ON WED.
OTHERWISE...EXPECT VFR FLIGHT CONDITIONS OUTSIDE CONVECTION OVER
THE NEXT 24 HOURS WITH PLENTY OF MID AND HIGH CLOUD DEBRIS THROUGH
THE TAF PERIOD.
13
&&
.PREV DISCUSSION... /ISSUED 1002 PM CDT TUE JUL 8 2014/
DISCUSSION...
AS OF 0245Z...COLD FRONT WAS LOCATED FROM THE SRN TX
PANHANDLE...INTO SRN OK...AND INTO NRN AR NEWD TOWARDS THE
BOOTHEEL OF MO. CONVECTION THAT DEVELOPED AHEAD OF THE FRONT
EARLIER THIS AFTERNOON CONTINUES TO MOVE SEWD. IT IS WORTH NOTING
THAT THESE STORMS HAVE BEEN VERY EFFICIENT RAIN PRODUCERS AND HAVE
ALSO PRODUCED SPORADIC WIND DAMAGE. LATEST RADAR TRENDS AND HI-RES
MODELS SUGGEST THIS COMPLEX WILL PROBABLY BRUSH OUR MOST NRN
COUNTIES IN SE OK/SW AR...BUT SHOULD LARGELY REMAIN N OF THE CWA
THROUGH 09/06Z. LATEST HRRR INDICATES CONVECTION WILL MOVE S INTO
THE CWA DURING THE EARLY MORNING HRS MAINLY AFFECTING THE NE HALF
OF THE AREA. THIS SEEMS REASONABLE AS THE CENTER OF THE UPPER
RIDGE OVER THE ROCKIES CONTINUES TO RETROGRADE WWD WHICH SHOULD
ALLOW THE FLOW ALOFT TO BECOME MORE NLY HELPING TO PUSH THE FRONT
INTO THE AREA.
HAVE TWEAKED POPS BASED ON LATEST RADAR TRENDS AND HRRR. MINOR
OTHER MINOR CHANGES TO MOST OF THE OTHER GRIDS BASED ON LATEST
OBS. MIN TEMP FCST FOR TONIGHT WAS LEFT INTACT. UPDATED PRODUCTS
HAVE BEEN SENT. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 74 94 73 94 73 / 20 30 20 20 20
MLU 73 92 72 92 72 / 30 50 30 30 30
DEQ 70 91 71 92 70 / 30 30 30 30 20
TXK 75 91 72 93 72 / 30 30 30 30 20
ELD 73 92 71 91 71 / 40 50 30 30 30
TYR 76 94 73 93 72 / 10 20 20 10 10
GGG 74 93 72 94 72 / 10 30 20 10 10
LFK 75 94 72 92 71 / 10 20 10 20 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
13
AREA FORECAST DISCUSSION
NWS GRAY ME
1014 AM EDT WED JUL 9 2014
.SYNOPSIS...
A SECONDARY COLD FRONT WILL APPROACH FROM THE WEST TODAY AND WILL
PUSH OFFSHORE TONIGHT. HIGH PRESSURE WILL BUILD IN FROM THE WEST
THURSDAY THROUGH FRIDAY. HIGH PRESSURE WILL SHIFT OFFSHORE ON
SATURDAY. A WEAK WARM FRONT WILL APPROACH FROM THE SOUTHWEST ON
SUNDAY AND WILL STALL SOUTH OF THE REGION SUNDAY NIGHT. A COLD
FRONT WILL MOVE IN FROM THE WEST ON MONDAY AND WILL CROSS THE
REGION MONDAY NIGHT. A SECONDARY COLD FRONT WILL APPROACH FROM THE
NORTHWEST TUESDAY AND WILL CROSS THE REGION TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...A QUICK UPDATE TO LWR POPS OVER THE NEXT COUPLE OF HOURS
AND WILL UPDATE TEMPS WITH OBSERVATION. SHOULD SEE CONVECTION
FIRE LATER THIS AFTERNOON. THIS CONVECTION SOULD BEGIN OVER THE
MOUNTAINS AND FOOTHILLS OF NEW HAMPSHIRE AND MAINE AS INDICATED BY
THE HRRR AND PROGRESS TOWARD THE COAST. SPC WRF INDICATES CONVECTION
LASTING INTO THE EVENING HOURS. CAN/T RULE OUT A STRONG OR
ISOLATED SVR STORM IN TH CWA. DEWPOINTS DROPPED A 3 TO 5 DEGREES
OVERNIGHT BUT WILL REMAIN IN THE UPPER 50S TO LOWER 60S TODAY.
PREVIOUS DISC...LINGERING SHOWERS AHEAD OF A COLD FRONT WILL QUICKLY
LIFT NORTHEAST OUT OF THE FORECAST AREA THROUGH DAYBREAK AS THE
FRONT SHIFTS OFFSHORE. EXPECT SKIES TO BECOME PARTLY TO MOSTLY
SUNNY ACROSS THE FORECAST AREA BY EARLY TO MID MORNING. A
SECONDARY COLD FRONT WILL APPROACH FROM THE WEST TODAY. EXPECT
MUCH OF THE DAY TO REMAIN DRY AS DRIER AIR SHIFTS IN BEHIND THE
FIRST FRONT. MAY SEE ENOUGH INSTABILITY AND MOISTURE POOLING AHEAD
OF THE SECONDARY FRONT TO KICK OFF A LATE AFTERNOON OR EVENING
SHOWER OR THUNDERSTORM...BUT NOT LOOKING FOR ANY WIDESPREAD
ACTIVITY AND SHOULD SEE THIS ACTIVITY ENDING BEFORE MIDNIGHT. HIGH
TEMPS WILL TOP OUT IN THE MID 70S TO LOWER 80S NORTH AND MID TO
UPPER 80S SOUTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
SECONDARY FRONT WILL PUSH OFFSHORE OVERNIGHT AND HIGH PRESSURE
WILL BEGIN BUILDING IN FROM THE WEST. EXPECT CLEARING SKIES AFTER
MIDNIGHT WITH SEASONABLE TEMPS.
THURSDAY LOOKING VERY NICE AS HIGH PRESSURE BUILDS IN FROM THE
WEST WITH COOLER TEMPS AND LOWER HUMIDITY. ASIDE FROM A FEW
MOUNTAIN CLOUDS...SHOULD SEE A MOSTLY SUNNY DAY WITH HIGHS FROM
THE MID 70S TO LOWER 80S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE SETTLES OVER THE REGION THURSDAY NGT THRU FRIDAY AS A
WEAK UPPER LVL SHORT WAVE AND WEAK SFC LOW MOVE OUT TO OUR S...TOO
FAR S TO AFFECT THE FCST AREA. THE HIGH STAYS OVER THE REGION FRIDAY
NGT AND SATURDAY THEN SLIDES OFF THE COAST SATURDAY NGT. EXPECT FAIR
WX WITH THIS HIGH THURSDAY NGT THRU SATURDAY NGT. THE TREND WILL BE
TO START OUT WITH PLEASANT SUMMER TEMPS WITH LOW HUMIDITY UNTIL THE
HIGH MOVES OFFSHORE AND A RETURN FLOW OF SW WINDS BRINGS INCREASING
HEAT AND HUMIDITY...WHICH WILL START ON SUNDAY.
THIS WILL BRING AN INCREASING RISK OF SHRA/TSTM ACTIVITY AS WELL.
THE VERY WARM AND HUMID WX LASTS THRU TUESDAY. AN UPPER LVL TROF
MOVES THRU MONDAY AND MONDAY EVE WHICH WILL HELP FOCUS MORE
WIDESPREAD SHRA/TSTM ACTIVITY. ANOTHER WEAKER UPPER LEVEL SHORT
WAVE IMPULSE MOVES IN FROM THE W TUESDAY/TUESDAY EVE AS IT PINWHEELS
AROUND AN UPPER LVL CLOSED LOW LOCATED IN CANADA N OF THE GREAT
LAKES. THIS SYSTEM AGAIN WILL HELP FOCUS SHRA/TSTM ACTIVITY IN THE
VERY WARM AND HUMID AIR MASS.
USED A BLEND OF VARIOUS MODELS...HPC GUIDANCE...PREVIOUS FCST FOR
PERSISTENCE AND CLIMATOLOGY FOR THE LONG TERM FCST.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
SHORT TERM...VFR TODAY THROUGH THURSDAY.
LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...MAINLY VFR THURSDAY
NGT THRU SATURDAY NGT UNDER THE INFLUENCE OF HIGH PRESSURE. WARMER
AND MORE HUMID AIR MOVES IN SUNDAY INCREASING THE CHC OF SHRA/TSTM
ACTIVITY WHICH MAY PRODUCE LOCAL MVFR/IFR CONDITIONS.
&&
.MARINE...
SHORT TERM...CONTINUING SCA`S FOR SEAS.
LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...HIGH PRESSURE KEEPS
WINDS AND SEAS WELL BELOW SCA LEVELS THURSDAY NGT THRU SATURDAY
NGT. AS THE HIGH MOVES OFFSHORE THE S SW FLOW WILL BE ENHANCED BY
A SEA BREEZE CAUSING WINDS TO INCREASE AND SEAS TO BUILD ON SUNDAY.
HOWEVER...THE FLOW WILL LIKELY NOT INCREASE ENOUGH TO CREATE SCA
CONDITIONS ACROSS THE WATERS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 PM EDT THIS
EVENING FOR ANZ150-152-154.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 AM EDT WED JUL 9 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 425 PM EDT TUE JUL 8 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA
AND A DOWNSTREAM TROF WITH AXIS EXTENDING FROM NCNTRL CANADA INTO
THE GREAT LAKES. ONE VIGOROUS SHORTWAVE MOVING THRU THE TROF BROUGHT
SHRA AND SOME TSRA TO MUCH OF THE FCST AREA LAST NIGHT INTO THE
MORNING HRS. THAT WAVE IS NOW E OF LAKE SUPERIOR. UPSTREAM...THERE
ARE A PAIR OF SHORTWAVES...ONE NEAR LAKE WINNIPEG AND THE OTHER JUST
TO THE E IN NRN ONTARIO. NEITHER ARE AS STRONG AS THE ONE THAT
AFFECTED THE AREA EARLIER TODAY. THE WAVE NEAR LAKE WINNIPEG IS THE
STRONGER OF THE TWO AND WILL BE THE MAIN PLAYER IN THE WEATHER HERE
TONIGHT. IN THE WAKE OF THE SHORTWAVE THAT PASSED EARLIER TODAY...
CLOUDS HAVE HELD TOUGH ACROSS MUCH OF THE AREA...AND THIS HAS
RESULTED IN A VERY COOL DAY FOR EARLY JULY STANDARDS. AS OF 19Z...
READINGS WERE STILL ONLY HOVERING AROUND 50F NEAR LAKE SUPERIOR AND
AROUND 60/LWR 60S ACROSS SCNTRL UPPER MI. SO FAR...TEMP HAS ONLY
REACHED 54F HERE AT THE NWS OFFICE. RECORD LOW MAX TEMP FOR TODAY IS
60F. IF LOW STRATUS HANGS AROUND THRU SUNSET...THAT RECORD WILL
FALL. WHERE CLOUDS HAVE BROKEN TO ALLOW FOR SUNSHINE FROM NE MN INTO
NRN WI...BUILD UP OF A LITTLE INSTABILITY UNDER COOL CYCLONIC NW
FLOW COMBINED WITH A SUBTLE SHORTWAVE HAS ALLOWED -SHRA/ISOLD TSRA
TO DEVELOP. THOSE SHRA HAVE BEEN BRUSHING MENOMINEE COUNTY.
OTHERWISE...ISOLD -SHRA/PATCHY -DZ HAVE BEEN OCCURRING ACROSS THE
AREA TODAY.
ISOLD -SHRA MAY LINGER NEAR THE WI/MI BORDER INTO THE EARLY EVENING
HRS. OTHERWISE...ATTENTION TURNS TO THE NW. ALTHOUGH UPSTREAM
SHORTWAVES WILL BE PASSING ACROSS THE UPPER LAKES DURING THE NIGHT
WHEN INSTABILITY IS DIMINISHING TOWARD DIURNAL MIN...EXPECT SOME
SHRA TO PERSIST NEAR THE TRACK OF THE WAVES...PARTICULARLY NEAR THE
AFORMENTIONED STRONGER WRN WAVE. THIS SHOULD PUT BEST POTENTIAL FOR
ISOLD/SCT SHRA ROUGHLY OVER THE W HALF OF UPPER MI. SINCE SHORTWAVE
IS WEAKER THAN LAST NIGHTS WAVE...MUCAPE IS UNDER 100J/KG...
SHOWALTER INDEX IS ABOVE 0 AND NO TSRA HAVE DEVELOPED WITH WAVE SO
FAR THIS AFTN...HAVE REMOVED ANY MENTION OF THUNDER TONIGHT.
ISOLD -SHRA MAY LINGER THRU WED MORNING WITH WEAK TRAILING SHORTWAVE
ENERGY. HOWEVER...WITH SOLID HEIGHT RISES TAKING OVER DURING THE DAY
(12HR 500MB HEIGHTS RISE 70-90M) ALONG WITH COLUMN DRYING...EXPECT A
DRYING TREND WED. THERE MAY BE A FEW AFTN -SHRA OVER THE SCNTRL AS
LAKE MICHIGAN LAKE BREEZE TRIES TO MOVE INLAND...SO ISOLD -SHRA
MENTION WAS LINGERED INTO THE AFTN IN THAT AREA. AS OPPOSED TO
TODAY...EXPECT MORE SUNSHINE TO DEVELOP WED UNDER DRYING/HEIGHT
RISES. THIS WILL HELP BOOST TEMPS TOWARD 70F INLAND. WHERE WINDS ARE
ONSHORE THRU THE DAY...TEMPS ALONG LAKE SUPERIOR WILL NOT GET OUT OF
THE 50S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM EDT WED JUL 9 2014
THU/THU NIGHT WILL BE DRY AS AN UPPER RIDGE BUILDS INTO THE AREA
WHILE A SFC RIDGE SLOWLY EXITS THE CWA. PRECIP CHANCES INCREASE FRI
INTO THE WEEKEND AS A SERIES OF SHORTWAVES MOVE ACROSS THE REGION
AHEAD OF A LOW PRESSURE SYSTEM THAT WILL SETTLE ACROSS CENTRAL
CANADA.
THE LEAD SHORTWAVE LOOKS TO BE PRETTY WEAK AND SHOULD MOVE ACROSS
THE AREA FRI AFTERNOON/EVENING. MOISTURE LOOKS TO BE LIMITED ON FRI
DUE TO LIMITED MOISTURE RETURN BEHIND THE DEPARTING SFC RIDGE. BEST
CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL BE OVER THE WRN
CWA WHERE MOISTURE WILL BE A BIT BETTER...RESULTING IN GREATER
INSTABILITY. MUCAPES UP TO 400J/KG AND 30KTS OF 0-6KM BULK SHEAR MAY
ALLOW FOR SOME STRONGER STORMS...BUT NO SEVERE WEATHER IS EXPECTED.
ANOTHER SHORTWAVE IS SET TO MOVE ACROSS THE AREA FRI NIGHT INTO
EARLY SAT...AND WITH GREATER MOISTURE/MOISTURE TRANSPORT PRECIP
CHANCES ARE HIGHER THAN FRI. IF ENOUGH CLEARING CAN OCCUR BEHIND
THIS ACTIVITY...CONVECTION MAY DEVELOP /PRIMARILY OVER SCENTRAL
UPPER MI/ ALONG A WEAK COLD FRONT MOVING ACROSS THE CWA. MODELS
GENERALLY SHOW AROUND 1500J/KG OF CAPE DEVELOPING ACROSS SCENTRAL
UPPER MI WITH AROUND 40KTS OF 0-6KM BULK SHEAR. WHILE IT IS
IMPORTANT TO STATE THAT SIGNIFICANT UNCERTAINTY EXISTS...STRONG TO
SEVERE STORMS ARE A POSSIBILITY ON SAT.
YET ANOTHER SHORTWAVE MAY MOVE THROUGH ON SUNDAY...DRAGGING ANOTHER
COLD FRONT THROUGH THE AREA. EARLY INDICATIONS ARE THAT ENOUGH
INSTABILITY MAY DEVELOP...ALONG WITH 0-6KM SHEAR OF 40-50KTS...TO
SUPPORT STRONGER STORMS...BUT DETAILS ARE UNCLEAR AT THIS TIME.
THERE IS QUITE A BIT MORE UNCERTAINTY GOING INTO NEXT WEEK AS MODELS
STRUGGLE TO CONSISTENTLY HANDLE THE TRACK/STRENGTH OF THE UPPER LOW
AS IT MOVES OUT OF CENTRAL CANADA. IT DOES APPEAR THAT TEMPERATURES
WILL BE MUCH COLDER THAN NORMAL AS 850MB TEMPS FALL AS LOW AS
3C...WITH SOME RECORD LOW MAXIMUM TEMPERATURES EVEN POSSIBLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1215 AM EDT WED JUL 9 2014
ALL TERMINALS WILL STAY VFR THROUGH THE PERIOD. DISTURBANCE DROPPING
INTO THE UPPER LAKES MAY BRING SOME -SHRA TO KIWD/KCMX EARLY THIS
MORNING...BUT PROBABILITY IS TOO LOW TO PUT IN THE TAFS FOR NOW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 353 AM EDT WED JUL 9 2014
LIGHTER WINDS WILL REMAIN...WITH GUSTS GENERALLY LESS THAN 25KTS
THROUGH THE PERIOD. LOW PRESSURE ACROSS CENTRAL QUEBEC...WITH A
TROUGH EXTENDING ACROSS LAKE SUPERIOR THIS MORNING...WILL EXIT EAST
TODAY AS HIGH PRESSURE PUSHES IN FROM THE WEST. LOOK FOR THE HIGH
PRESSURE SYSTEM TO BUILD OVER THE REGION ON THURSDAY...BEFORE SLOWLY
EXITING TO THE NEW ENGLAND STATES LATE THURSDAY THROUGH FRIDAY. LOW
PRESSURE OVER NORTHERN MANITOBA THURSDAY NIGHT IS EXPECTED TO SHIFT
OVER HUDSON BAY...AND ACROSS ONTARIO ON SUNDAY. THIS WILL ALLOW A
TROUGH TO CROSS THE UPPER GREAT LAKES LATE FRIDAY NIGHT THAT SHOULD
DEEPEN ACROSS THE AREA ON SUNDAY. FOG WILL BE POSSIBLE ACROSS LAKE
SUPERIOR FRIDAY AFTERNOON THROUGH AT LEAST SATURDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...07
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
303 AM EDT WED JUL 9 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 425 PM EDT TUE JUL 8 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA
AND A DOWNSTREAM TROF WITH AXIS EXTENDING FROM NCNTRL CANADA INTO
THE GREAT LAKES. ONE VIGOROUS SHORTWAVE MOVING THRU THE TROF BROUGHT
SHRA AND SOME TSRA TO MUCH OF THE FCST AREA LAST NIGHT INTO THE
MORNING HRS. THAT WAVE IS NOW E OF LAKE SUPERIOR. UPSTREAM...THERE
ARE A PAIR OF SHORTWAVES...ONE NEAR LAKE WINNIPEG AND THE OTHER JUST
TO THE E IN NRN ONTARIO. NEITHER ARE AS STRONG AS THE ONE THAT
AFFECTED THE AREA EARLIER TODAY. THE WAVE NEAR LAKE WINNIPEG IS THE
STRONGER OF THE TWO AND WILL BE THE MAIN PLAYER IN THE WEATHER HERE
TONIGHT. IN THE WAKE OF THE SHORTWAVE THAT PASSED EARLIER TODAY...
CLOUDS HAVE HELD TOUGH ACROSS MUCH OF THE AREA...AND THIS HAS
RESULTED IN A VERY COOL DAY FOR EARLY JULY STANDARDS. AS OF 19Z...
READINGS WERE STILL ONLY HOVERING AROUND 50F NEAR LAKE SUPERIOR AND
AROUND 60/LWR 60S ACROSS SCNTRL UPPER MI. SO FAR...TEMP HAS ONLY
REACHED 54F HERE AT THE NWS OFFICE. RECORD LOW MAX TEMP FOR TODAY IS
60F. IF LOW STRATUS HANGS AROUND THRU SUNSET...THAT RECORD WILL
FALL. WHERE CLOUDS HAVE BROKEN TO ALLOW FOR SUNSHINE FROM NE MN INTO
NRN WI...BUILD UP OF A LITTLE INSTABILITY UNDER COOL CYCLONIC NW
FLOW COMBINED WITH A SUBTLE SHORTWAVE HAS ALLOWED -SHRA/ISOLD TSRA
TO DEVELOP. THOSE SHRA HAVE BEEN BRUSHING MENOMINEE COUNTY.
OTHERWISE...ISOLD -SHRA/PATCHY -DZ HAVE BEEN OCCURRING ACROSS THE
AREA TODAY.
ISOLD -SHRA MAY LINGER NEAR THE WI/MI BORDER INTO THE EARLY EVENING
HRS. OTHERWISE...ATTENTION TURNS TO THE NW. ALTHOUGH UPSTREAM
SHORTWAVES WILL BE PASSING ACROSS THE UPPER LAKES DURING THE NIGHT
WHEN INSTABILITY IS DIMINISHING TOWARD DIURNAL MIN...EXPECT SOME
SHRA TO PERSIST NEAR THE TRACK OF THE WAVES...PARTICULARLY NEAR THE
AFORMENTIONED STRONGER WRN WAVE. THIS SHOULD PUT BEST POTENTIAL FOR
ISOLD/SCT SHRA ROUGHLY OVER THE W HALF OF UPPER MI. SINCE SHORTWAVE
IS WEAKER THAN LAST NIGHTS WAVE...MUCAPE IS UNDER 100J/KG...
SHOWALTER INDEX IS ABOVE 0 AND NO TSRA HAVE DEVELOPED WITH WAVE SO
FAR THIS AFTN...HAVE REMOVED ANY MENTION OF THUNDER TONIGHT.
ISOLD -SHRA MAY LINGER THRU WED MORNING WITH WEAK TRAILING SHORTWAVE
ENERGY. HOWEVER...WITH SOLID HEIGHT RISES TAKING OVER DURING THE DAY
(12HR 500MB HEIGHTS RISE 70-90M) ALONG WITH COLUMN DRYING...EXPECT A
DRYING TREND WED. THERE MAY BE A FEW AFTN -SHRA OVER THE SCNTRL AS
LAKE MICHIGAN LAKE BREEZE TRIES TO MOVE INLAND...SO ISOLD -SHRA
MENTION WAS LINGERED INTO THE AFTN IN THAT AREA. AS OPPOSED TO
TODAY...EXPECT MORE SUNSHINE TO DEVELOP WED UNDER DRYING/HEIGHT
RISES. THIS WILL HELP BOOST TEMPS TOWARD 70F INLAND. WHERE WINDS ARE
ONSHORE THRU THE DAY...TEMPS ALONG LAKE SUPERIOR WILL NOT GET OUT OF
THE 50S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 302 AM EDT WED JUL 9 2014
THU/THU NIGHT WILL BE DRY AS AN UPPER RIDGE BUILDS INTO THE AREA
WHILE A SFC RIDGE SLOWLY EXITS THE CWA. PRECIP CHANCES INCREASE FRI
INTO THE WEEKEND AS A SERIES OF SHORTWAVES MOVE ACROSS THE REGION
AHEAD OF A LOW PRESSURE SYSTEM THAT WILL SETTLE ACROSS CENTRAL
CANADA.
THE LEAD SHORTWAVE LOOKS TO BE PRETTY WEAK AND SHOULD MOVE ACROSS
THE AREA FRI AFTERNOON/EVENING. MOISTURE LOOKS TO BE LIMITED ON FRI
DUE TO LIMITED MOISTURE RETURN BEHIND THE DEPARTING SFC RIDGE. BEST
CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL BE OVER THE WRN
CWA WHERE MOISTURE WILL BE A BIT BETTER...RESULTING IN GREATER
INSTABILITY. MUCAPES UP TO 400J/KG AND 30KTS OF 0-6KM BULK SHEAR MAY
ALLOW FOR SOME STRONGER STORMS...BUT NO SEVERE WEATHER IS EXPECTED.
ANOTHER SHORTWAVE IS SET TO MOVE ACROSS THE AREA FRI NIGHT INTO
EARLY SAT...AND WITH GREATER MOISTURE/MOISTURE TRANSPORT PRECIP
CHANCES ARE HIGHER THAN FRI. IF ENOUGH CLEARING CAN OCCUR BEHIND
THIS ACTIVITY...CONVECTION MAY DEVELOP /PRIMARILY OVER SCENTRAL
UPPER MI/ ALONG A WEAK COLD FRONT MOVING ACROSS THE CWA. MODELS
GENERALLY SHOW AROUND 1500J/KG OF CAPE DEVELOPING ACROSS SCENTRAL
UPPER MI WITH AROUND 40KTS OF 0-6KM BULK SHEAR. WHILE IT IS
IMPORTANT TO STATE THAT SIGNIFICANT UNCERTAINTY EXISTS...STRONG TO
SEVERE STORMS ARE A POSSIBILITY ON SAT.
YET ANOTHER SHORTWAVE MAY MOVE THROUGH ON SUNDAY...DRAGGING ANOTHER
COLD FRONT THROUGH THE AREA. EARLY INDICATIONS ARE THAT ENOUGH
INSTABILITY MAY DEVELOP...ALONG WITH 0-6KM SHEAR OF 40-50KTS...TO
SUPPORT STRONGER STORMS...BUT DETAILS ARE UNCLEAR AT THIS TIME.
THERE IS QUITE A BIT MORE UNCERTAINTY GOING INTO NEXT WEEK AS MODELS
STRUGGLE TO CONSISTENTLY HANDLE THE TRACK/STRENGTH OF THE UPPER LOW
AS IT MOVES OUT OF CENTRAL CANADA. IT DOES APPEAR THAT TEMPERATURES
WILL BE MUCH COLDER THAN NORMAL AS 850MB TEMPS FALL AS LOW AS
3C...WITH SOME RECORD LOW MAXIMUM TEMPERATURES EVEN POSSIBLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1215 AM EDT WED JUL 9 2014
ALL TERMINALS WILL STAY VFR THROUGH THE PERIOD. DISTURBANCE DROPPING
INTO THE UPPER LAKES MAY BRING SOME -SHRA TO KIWD/KCMX EARLY THIS
MORNING...BUT PROBABILITY IS TOO LOW TO PUT IN THE TAFS FOR NOW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 326 PM EDT TUE JUL 8 2014
WINDS ARE EXPECTED TO STAY BELOW 25 KTS THROUGH THE PERIOD OUTSIDE
OF ANY STRONGER THUNDERSTORMS. GREATEST CHANCES FOR THUNDERSTORMS
WILL BE FRIDAY NIGHT INTO SATURDAY AS A COLD FRONT GRADUALLY CROSSES
LAKE SUPERIOR. COULD SEE DENSE FOG AT TIMES FOR THE UPCOMING WEEKEND
OVER NORTHERN SECTIONS AS SOUTH WINDS TRANSPORT MORE HUMID AIR
ACROSS LK SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1216 AM EDT WED JUL 9 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 425 PM EDT TUE JUL 8 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA
AND A DOWNSTREAM TROF WITH AXIS EXTENDING FROM NCNTRL CANADA INTO
THE GREAT LAKES. ONE VIGOROUS SHORTWAVE MOVING THRU THE TROF BROUGHT
SHRA AND SOME TSRA TO MUCH OF THE FCST AREA LAST NIGHT INTO THE
MORNING HRS. THAT WAVE IS NOW E OF LAKE SUPERIOR. UPSTREAM...THERE
ARE A PAIR OF SHORTWAVES...ONE NEAR LAKE WINNIPEG AND THE OTHER JUST
TO THE E IN NRN ONTARIO. NEITHER ARE AS STRONG AS THE ONE THAT
AFFECTED THE AREA EARLIER TODAY. THE WAVE NEAR LAKE WINNIPEG IS THE
STRONGER OF THE TWO AND WILL BE THE MAIN PLAYER IN THE WEATHER HERE
TONIGHT. IN THE WAKE OF THE SHORTWAVE THAT PASSED EARLIER TODAY...
CLOUDS HAVE HELD TOUGH ACROSS MUCH OF THE AREA...AND THIS HAS
RESULTED IN A VERY COOL DAY FOR EARLY JULY STANDARDS. AS OF 19Z...
READINGS WERE STILL ONLY HOVERING AROUND 50F NEAR LAKE SUPERIOR AND
AROUND 60/LWR 60S ACROSS SCNTRL UPPER MI. SO FAR...TEMP HAS ONLY
REACHED 54F HERE AT THE NWS OFFICE. RECORD LOW MAX TEMP FOR TODAY IS
60F. IF LOW STRATUS HANGS AROUND THRU SUNSET...THAT RECORD WILL
FALL. WHERE CLOUDS HAVE BROKEN TO ALLOW FOR SUNSHINE FROM NE MN INTO
NRN WI...BUILD UP OF A LITTLE INSTABILITY UNDER COOL CYCLONIC NW
FLOW COMBINED WITH A SUBTLE SHORTWAVE HAS ALLOWED -SHRA/ISOLD TSRA
TO DEVELOP. THOSE SHRA HAVE BEEN BRUSHING MENOMINEE COUNTY.
OTHERWISE...ISOLD -SHRA/PATCHY -DZ HAVE BEEN OCCURRING ACROSS THE
AREA TODAY.
ISOLD -SHRA MAY LINGER NEAR THE WI/MI BORDER INTO THE EARLY EVENING
HRS. OTHERWISE...ATTENTION TURNS TO THE NW. ALTHOUGH UPSTREAM
SHORTWAVES WILL BE PASSING ACROSS THE UPPER LAKES DURING THE NIGHT
WHEN INSTABILITY IS DIMINISHING TOWARD DIURNAL MIN...EXPECT SOME
SHRA TO PERSIST NEAR THE TRACK OF THE WAVES...PARTICULARLY NEAR THE
AFORMENTIONED STRONGER WRN WAVE. THIS SHOULD PUT BEST POTENTIAL FOR
ISOLD/SCT SHRA ROUGHLY OVER THE W HALF OF UPPER MI. SINCE SHORTWAVE
IS WEAKER THAN LAST NIGHTS WAVE...MUCAPE IS UNDER 100J/KG...
SHOWALTER INDEX IS ABOVE 0 AND NO TSRA HAVE DEVELOPED WITH WAVE SO
FAR THIS AFTN...HAVE REMOVED ANY MENTION OF THUNDER TONIGHT.
ISOLD -SHRA MAY LINGER THRU WED MORNING WITH WEAK TRAILING SHORTWAVE
ENERGY. HOWEVER...WITH SOLID HEIGHT RISES TAKING OVER DURING THE DAY
(12HR 500MB HEIGHTS RISE 70-90M) ALONG WITH COLUMN DRYING...EXPECT A
DRYING TREND WED. THERE MAY BE A FEW AFTN -SHRA OVER THE SCNTRL AS
LAKE MICHIGAN LAKE BREEZE TRIES TO MOVE INLAND...SO ISOLD -SHRA
MENTION WAS LINGERED INTO THE AFTN IN THAT AREA. AS OPPOSED TO
TODAY...EXPECT MORE SUNSHINE TO DEVELOP WED UNDER DRYING/HEIGHT
RISES. THIS WILL HELP BOOST TEMPS TOWARD 70F INLAND. WHERE WINDS ARE
ONSHORE THRU THE DAY...TEMPS ALONG LAKE SUPERIOR WILL NOT GET OUT OF
THE 50S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 326 PM EDT TUE JUL 8 2014
LARGE SCALE PATTERN LOOKS SIMILAR TO WHAT WAS OCCURRING THIS TIME
LAST WEEK. TROUGHING TO START THE WEEK THEN RELAXING HEIGHTS MORE
ZONAL FLOW LATE WEEK INTO THE WEEKEND. SEEMS THIS PATTERN CHANGES
BACK TO TROUGHING QUICKER THOUGH WITH ECMWF/GFS/GEM-NH TRENDING BACK
TO TROUGHING BY SUNDAY AND PERSISTING INTO EARLY NEXT WEEK. PRIMARY
RAIN CHANCES OCCUR AS THE FLOW GOES ZONAL...FRIDAY INTO SATURDAY.
DECENT AGREEMENT THAT MAIN COLD FROPA OCCURS LATE FRIDAY NIGHT INTO
SATURDAY. DPROG/DT...SEEING HOW THE MODELS ARE CHANGING OVER THEIR
RECENT RUNS...INDICATES STRONG CONSISTENCY FM THE MODELS IN MASS
FIELDS /MID-LEVEL HEIGHTS AND MSLP/ THROUGH SATURDAY.
AHEAD OF THE COLD FROPA ON SATURDAY...HIGH PRESSURE AND MAINLY DRY
WEATHER IS OVER THE REGION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
LOW TEMPS COOLEST ON WED NIGHT WITH PWATS AROUND 50 PCT OF NORMAL
BENEATH THE RIDGE AXIS. FAVORED COLD SPOTS INTERIOR MAY SEE LOWS
AROUND 40 DEGREES. OTHERWISE...READINGS WILL BE IN THE 40S TO AROUND
50. WARMER NIGHT EXPECTED ON THURSDAY NIGHT AS SOUTHERLY RETURN FLOW
DEVELOPS AS RIDGE AXIS SLIDES EAST. MAX TEMPS ON THURSDAY AROUND
NORMAL IN THE MID TO UPPER 70S...WITH ONLY LOCAL COOLING NEAR IMMEDIATE
GREAT LAKES SHORES.
CLOUDS WILL INCREASE LATER THURSDAY NIGHT AS SHORTWAVES BEGIN TO
WORK ACROSS NORTHERN PLAINS AND UPPER GREAT LAKES IN A MORE WESTERLY
FLOW ALOFT. LEAD SHORTWAVE CURRENTLY OFFSHORE OF OREGON SLIDES ACROSS
ON FRIDAY. STRONGER WAVE IS FORECAST TO CROSS MANTIOBA AND NORTHWEST
ONTARIO. H85-H7 MOISTURE TRANSPORT LOOKS SPLIT IN TWO AREAS...STRONGEST
CLOSER TO THE CANADIAN TROUGH. INSTABILITY AXIS BOTH AT SFC AND ALOFT
ELEVATED LAGS BOTH WAVES SO NOT EXPECTING STRONG STORMS LATER THU
NIGHT OR FRIDAY. THETA-E ADVECTION RAMPS UP FRIDAY NIGHT INTO
SATURDAY MORNING AHEAD OF COLD FRONT WHICH WILL SUPPORT GREATER
COVERAGE OF SHRA/TSRA. INSTABILITY REMAINS ONLY MARGINAL WITH
200-400J/KG OF 1-6KM MUCAPE AS GREATEST MLCAPE AND 1-6KM MUCAPE
SETTLES MORE SOUTH INTO MIDDLE MISSISSIPPI VALLEY THAN EAST ACROSS
THE GREAT LAKES. DEEP LAYER SHEAR VALUES ARE UP TO 30 KTS FRIDAY
NIGHT...SO CANNOT COUNT OUT SOME STRONGER STORMS. SEVERE RISK DOES
APPEAR PRETTY MARGINAL.
DEEP LAYER SHEAR INCREASES TO 40+ KTS BY SATURDAY AFTN. 12Z ECMWF
INDICATES MORE MLCAPE THAN EARLIER RUNS...CENTERED OVER CNTRL UPR
MICHIGAN IN THE AFTN. LOOKS AS IF THE COLD FRONT MAY BE SLIGHTLY
SLOWER. AS LONG AS THE SHRA/TSRA FROM FRIDAY NIGHT AND ASSOCIATED
COOLING/STABILIZING AFFECTS ARE OUT OF THE WAY IN TIME...COULD SEE
ISOLD STRONG OR SEVERE STORMS OVR CNTRL UPR MICHIGAN SATURDAY AFTN
IF THERE IS ENOUGH SUNSHINE. H7 WINDS ARE MORE WESTERLY. ATTM BASED
ON EXPECTED POSITION OF COLD FRONT AND A MORE WEST TO EAST MEAN
STORM MOTION...LOOKS LIKE GREATEST RISK FOR STRONGER STORMS WOULD BE
OVER SCNTRL UPR MICHIGAN. WHATEVER SHRA/TSRA ARE AROUND SATURDAY
AFTERNOON...SHOULD DIMINISH/END LATER SATURDAY NIGHT.
MODEL CONSISTENCY BECOMES MORE JUMPY SUNDAY/MONDAY...BUT LAST COUPLE
RUNS OF EACH MODEL IS HEADING TOWARD MORE TROUGHING/COOLER WEATHER.
PRIMARY ISSUE IS POSSIBLE DEVELOPMENT OF STRONGER SFC LOW PRESSURE
ON LEADING EDGE OF MID-LEVEL TROUGH SATURDAY NIGHT INTO SUNDAY.
RECENT RUNS OF GEM-NH STILL HANGING ON TO THIS IDEA WHILE 06Z GFS
WAS THE FIRST GFS RUN SINCE JULY 7/12Z TO SHOW SIMILAR SOLN. 12Z GFS
DOES NOT HAVE IT AGAIN. ECMWF SHOWED STRONGER LOW ON THE JULY 6/12Z
RUN...BUT HAS SINCE BACKED AWAY.
BY EARLY NEXT WEEK...TREND IS CERTAINLY THERE FOR A RETURN TO
TROUGHING AND BLO NORMAL TEMPS...LIKELY OVER 20 DEGREES BLO NORMAL
FOR DAYTIME HIGHS NEAR LK SUPERIOR. CORE OF COOLEST AIR AT H85 OVER
MANITOBA AND ONTARIO BOTTOMS OUT AROUND 0C ON THE ECMWF AND AROUND
+2C ON THE GFS ON MONDAY. UPPER LOW CENTER SETTLES ACROSS GREAT
LAKES BY NEXT TUESDAY WITH H85 TEMPS STAYING BLO +5C AND PLENTY OF
H85-H7 MOISTURE. SFC LOW FORECAST TO BE EAST OF LK SUPERIOR REGION...
SO NORTH WINDS WILL KEEP UPPER GREAT LAKES VERY COOL. RECORD LOW
MAXES FOR MID JULY ARE IN THE UPPER 50S TO LOWER 60S...BUT SOME
VALUES IN JULY ARE EVEN IN THE LOWER 50S. MAY SEE SOME TEMPS EARLY
NEXT WEEK COME CLOSE TO THESE LOWER READINGS. IT IS CERTAINLY WITHIN
THE REALM OF POSSIBILITY. CHANCES OF SEEING CLOUDS AND SHOWERS IN THE
PATTERN PRETTY HIGH...SO THAT WOULD ONLY HELP KEEP TEMPS ON THE COOL
SIDE. PROBABLY GOES WITHOUT SAYING...BUT NO REAL STRETCHES OF WELL
ABOVE NORMAL TEMPS ARE SEEN ANYTIME IN THE MEDIUM RANGE TIME PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1215 AM EDT WED JUL 9 2014
ALL TERMINALS WILL STAY VFR THROUGH THE PERIOD. DISTURBANCE DROPPING
INTO THE UPPER LAKES MAY BRING SOME -SHRA TO KIWD/KCMX EARLY THIS
MORNING...BUT PROBABILITY IS TOO LOW TO PUT IN THE TAFS FOR NOW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 326 PM EDT TUE JUL 8 2014
WINDS ARE EXPECTED TO STAY BELOW 25 KTS THROUGH THE PERIOD OUTSIDE
OF ANY STRONGER THUNDERSTORMS. GREATEST CHANCES FOR THUNDERSTORMS
WILL BE FRIDAY NIGHT INTO SATURDAY AS A COLD FRONT GRADUALLY CROSSES
LAKE SUPERIOR. COULD SEE DENSE FOG AT TIMES FOR THE UPCOMING WEEKEND
OVER NORTHERN SECTIONS AS SOUTH WINDS TRANSPORT MORE HUMID AIR
ACROSS LK SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1046 PM CDT THU JUL 10 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 325 PM CDT THU JUL 10 2014
MAIN CONCERN FOR THE SHORT TERM IS TURNING OUT TO BE THE POTENTIAL
FOR HEAVY RAIN TONIGHT OVER WESTERN MN BASED ON LATEST HI-RES CAMS.
THIS AFTERNOON...SRLY LOW LEVEL WINDS HAVE BECOME WELL ESTABLISHED
AS HIGH PRESSURE HAS NOW PUSHED OFF TO MICHIGAN. THESE SRLY WINDS
HAVE FINALLY BROUGHT THE CANADIAN SMOKE PLUME THAT WAS LINGERING
JUST TO OUR SW THE PAST COUPLE OF DAYS UP INTO CENTRAL AND SRN
MN...HENCE THE MILKY COLOR IN THE SKY AND OCCASIONAL HAZE REPORTS
ACROSS THE AREA THIS AFTERNOON. BACK TO THE WEST...A SHORT WAVE CAN
BE SEEN APPROACHING WRN MN...THOUGH THIS HAS DONE NOTHING MORE THAN
CREATE MAINLY VIRGA...AND THIS IS EXPECTED TO BE THE CASE AS IT
WORKS ACROSS MN THIS EVENING. INSTEAD...THE MAIN WAVE DRIVING THE
WEATHER ACROSS THE NRN PLAINS IS THE CUT-OFF H5 LOW CURRENTLY
SPINNING FROM ALBERTA INTO SASKATCHEWAN. THIS WAVE IS WHAT IS
FORCING THE LLJ TO BE BACK MORE ACROSS CENTRAL INTO THE ERN DAKOTAS
TODAY.
FOR THIS AFTERNOON INTO TONIGHT...FAVORED THE FORECAST FOR POPS AND
QPF TOWARD THE RAP/ECMWF ALONG WITH JUST ABOUT ANY HI-RES CAM YOU
CAN FIND THAT WAS RUN AT 12Z OR LATER. ALL OF THESE MODELS SHOW
THUNDERSTORMS DEVELOPING OVER NE SODAK AROUND 21/22Z AND SLOWLY
WORKING EAST INTO WRN MN THIS EVENING. ALL HI-RES MODELS SHOW 2-4
INCHES OF RAIN FALLING IN THE GENERALLY VCNTY OF THE NE SODAK/WRN MN
BORDER. LOOKING AT THE RAP...THIS LOOKS TO BE TIED TO WHAT IS
HAPPENING IN THE 925-850MB LAYER. THE RAP HAS BEEN PRETTY CONSISTENT
WITH SHOWING MOISTURE TRANSPORT IN THIS LAYER INCREASING THIS
AFTERNOON ACROSS SE SODAK...WITH THE EDGE OF IT UP INTO NE SODAK. IN
ADDITION TO THAT...THE RAP SHOWS A STRONG FGEN SIGNAL AT THE NOSE OF
THIS LLJ. THE REASON FOR THE HEAVY PRECIP SIGNAL IS THIS LLJ AND ITS
ASSOCIATED FGEN REMAIN MORE OR LESS STATIONARY OUT NEAR THE MN/SD
BORDER THROUGH ABOUT 6Z. WITH THIS FORCING REMAINING
STATIONARY...THERE WILL BE A PERIOD THROUGH ABOUT 6Z WHERE THE
ACTIVITY CAN TRAIN OUT THERE...BEFORE EVERYTHING STARTS TO BECOME
MORE PROGRESSIVE LATE TONIGHT AS THE CANADIAN UPPER LOW MOVES TOWARD
MANITOBA. QPF GRIDS USED WERE A BLEND OF THE SHORT TERM CAMS
TEMPERED WITH THE 12Z ECMWF. THIS RESULTED IN 1-2 INCHES OF QPF
THROUGH FRI MORNING OUT IN WRN MN...WHICH MAY STILL BE CONSERVATIVE
CONSIDERING SOME OF THE HI-RES MODELS HAVE BEEN SHOWING THE
POTENTIAL FOR ISOLATED RAINFALL AMOUNTS OVER 5 INCHES TONIGHT...SO
THIS IS SOMETHING THAT CERTAINLY BEARS SOME WATCHING.
THROUGH THE REST OF THE SHORT TERM...THE LLJ AND SFC FRONT WILL
SLOWLY WORK EAST WITH TIME DURING THE MORNING ON FRIDAY...WITH BEST
RAINFALL CHANCES FOR ERN MN/WRN WI LIKELY COMING DURING THE MORNING
AS REMNANTS OF TONIGHTS ACTIVITY SHIFTS EAST. BACKED OFF SOME ON
POPS FRIDAY AFTERNOON...AS CAMS ARE FAIRLY SPARSE WITH ACTIVITY AS
WE LOOSE THE DEFINITION ON THE SFC FRONT...WHICH WILL COINCIDE WITH
A WEAKENING OF THE LLJ AS WE GET INTO SUBSIDENCE ASSOCIATED WITH THE
RIGHT ENTRANCE REGION OF THE UPPER JET WORKING ACROSS THE
INTERNATIONAL BORDER. WITH LESS ACTIVITY EXPECTED...ALSO BOOSTED
TEMPS A FEW DEGREES OUT IN WRN WI AS IT IS NOT LOOKING AS LIKELY FOR
FRIDAY TO BE DOMINATED BY CLOUDS AND RAIN AS WAS PREVIOUSLY
ANTICIPATED.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 PM CDT THU JUL 10 2014
AS WE PROGRESS THROUGH THE SATURDAY-THURSDAY PERIOD WE/LL SEE QUITE
THE EVOLUTION OF LARGE SCALE FEATURES AND WEATHER ACROSS THE AREA.
THINGS WILL START OUT WARM WITH THE UPPER JET NORTH OF THE AREA...
BUT AN UNSEASONABLY DEEP UPPER LOW WILL DROP SOUTH/EAST FROM CENTRAL
CANADA INTO THE UPPER MIDWEST AND GREAT LAKES REGION DURING THE
SUNDAY NIGHT THROUGH TUESDAY PERIOD. THIS WILL BRING VERY COOL
TEMPERATURES TO MUCH OF THE REGION... WITH THE HEART OF THE COLD AIR
TRACKING ACROSS MINNESOTA AND POINTS EAST. SOME PCPN CHANCES WILL
LOITER ACROSS THE REGION SATURDAY INTO SUNDAY PRIOR TO THE ARRIVAL
OF THE COLD FRONT AND UPPER TROUGH... WITH DIURNAL CHANCES FOR PCPN
AFTER THAT AS THE UPPER COLD POOL SWINGS ACROSS THE REGION. BEST
CHANCES FOR PCPN PRIOR TO FROPA WILL BE ACROSS THE SOUTHERN PORTIONS
OF THE AREA WHERE THE BAROCLINIC ZONE AND BEST INSTABILITY ARE
PROGGED... WITH CHANCES FOR DIURNAL SHRA FOLLOWING FROPA LOCATED
OVER EASTERN AREAS WHERE BOUNDARY LAYER CYCLONIC FLOW WILL BE MOST
PREVALENT AND LOW-MID LEVEL LAPSE RATES WILL BE STEEPEST BENEATH THE
MID-UPPER LEVEL COLD POOL. WE WILL SEE RIDGING BEGIN TO WORK INTO
THE AREA AFTER TUESDAY... WITH DRY WEATHER AND MODERATING
TEMPERATURES FOR THE LAST FEW DAYS OF THE FORECAST PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1046 PM CDT THU JUL 10 2014
SHOWERS AND ISOLATED THUNDERSTORMS ARE INCREASING LATE THIS
EVENING ACROSS CENTRAL AREAS OF MN. THIS ACTIVITY IS EXPECTED TO
EXPAND SOUTH AND TOWARD KRWF AND KSTC BY 09Z. STILL APPEARS TO BE
A FEW HOURS OF ON AND OFF SHOWERS AND THUNDERSTORMS. THE PICTURE
IS NOT AS CLEAR FOR THE TWIN CITIES AND POINTS EAST. IT MAY TAKE
UNTIL AROUND 12Z FOR ANY SUBSTANTIAL SHOWERS TO REACH KMSP AND
THROUGH 16Z ON OVER TO KEAU. CONFIDENCE HAS INCREASED ENOUGH TO
INDICATE A FEW HOURS OF MVFR CIGS (025-030) AT KAXN...KSTC AND
KRWF FRIDAY MORNING IN THE MOIST SOUTHERLY FLOW. LOWEST INDICATED
CEILINGS FOR KMSP AND POINTS EAST ON FRIDAY WAS 035. MUCH OF THE
SHRA/TSRA ACTIVITY SHOULD BE OVER BY FRIDAY AFTERNOON WITH THE
EXCEPTION OF KEAU WHERE A PROB30 GROUP WAS USED.
KMSP...ORGANIZED SHOWERS AND A FEW THUNDERSTORMS NOT EXPECTED
UNTIL AFTER 11Z. SCATTERED SHOWERS AND NEAR MVFR CEILINGS (035)
INDICATED FOR THE LATE MORNING WITH DRY CONDITIONS THEREAFTER.
/OUTLOOK FOR KMSP/
SAT...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WIND NW AT 5 KTS.
SUN...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WINDS W AT 5-10 KTS.
MON...VFR WITH MVFR CIGS/SHRA POSSIBLE. WIND NW AT 10-20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...TRH
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
649 PM CDT THU JUL 10 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 325 PM CDT THU JUL 10 2014
MAIN CONCERN FOR THE SHORT TERM IS TURNING OUT TO BE THE POTENTIAL
FOR HEAVY RAIN TONIGHT OVER WESTERN MN BASED ON LATEST HI-RES CAMS.
THIS AFTERNOON...SRLY LOW LEVEL WINDS HAVE BECOME WELL ESTABLISHED
AS HIGH PRESSURE HAS NOW PUSHED OFF TO MICHIGAN. THESE SRLY WINDS
HAVE FINALLY BROUGHT THE CANADIAN SMOKE PLUME THAT WAS LINGERING
JUST TO OUR SW THE PAST COUPLE OF DAYS UP INTO CENTRAL AND SRN
MN...HENCE THE MILKY COLOR IN THE SKY AND OCCASIONAL HAZE REPORTS
ACROSS THE AREA THIS AFTERNOON. BACK TO THE WEST...A SHORT WAVE CAN
BE SEEN APPROACHING WRN MN...THOUGH THIS HAS DONE NOTHING MORE THAN
CREATE MAINLY VIRGA...AND THIS IS EXPECTED TO BE THE CASE AS IT
WORKS ACROSS MN THIS EVENING. INSTEAD...THE MAIN WAVE DRIVING THE
WEATHER ACROSS THE NRN PLAINS IS THE CUT-OFF H5 LOW CURRENTLY
SPINNING FROM ALBERTA INTO SASKATCHEWAN. THIS WAVE IS WHAT IS
FORCING THE LLJ TO BE BACK MORE ACROSS CENTRAL INTO THE ERN DAKOTAS
TODAY.
FOR THIS AFTERNOON INTO TONIGHT...FAVORED THE FORECAST FOR POPS AND
QPF TOWARD THE RAP/ECMWF ALONG WITH JUST ABOUT ANY HI-RES CAM YOU
CAN FIND THAT WAS RUN AT 12Z OR LATER. ALL OF THESE MODELS SHOW
THUNDERSTORMS DEVELOPING OVER NE SODAK AROUND 21/22Z AND SLOWLY
WORKING EAST INTO WRN MN THIS EVENING. ALL HI-RES MODELS SHOW 2-4
INCHES OF RAIN FALLING IN THE GENERALLY VCNTY OF THE NE SODAK/WRN MN
BORDER. LOOKING AT THE RAP...THIS LOOKS TO BE TIED TO WHAT IS
HAPPENING IN THE 925-850MB LAYER. THE RAP HAS BEEN PRETTY CONSISTENT
WITH SHOWING MOISTURE TRANSPORT IN THIS LAYER INCREASING THIS
AFTERNOON ACROSS SE SODAK...WITH THE EDGE OF IT UP INTO NE SODAK. IN
ADDITION TO THAT...THE RAP SHOWS A STRONG FGEN SIGNAL AT THE NOSE OF
THIS LLJ. THE REASON FOR THE HEAVY PRECIP SIGNAL IS THIS LLJ AND ITS
ASSOCIATED FGEN REMAIN MORE OR LESS STATIONARY OUT NEAR THE MN/SD
BORDER THROUGH ABOUT 6Z. WITH THIS FORCING REMAINING
STATIONARY...THERE WILL BE A PERIOD THROUGH ABOUT 6Z WHERE THE
ACTIVITY CAN TRAIN OUT THERE...BEFORE EVERYTHING STARTS TO BECOME
MORE PROGRESSIVE LATE TONIGHT AS THE CANADIAN UPPER LOW MOVES TOWARD
MANITOBA. QPF GRIDS USED WERE A BLEND OF THE SHORT TERM CAMS
TEMPERED WITH THE 12Z ECMWF. THIS RESULTED IN 1-2 INCHES OF QPF
THROUGH FRI MORNING OUT IN WRN MN...WHICH MAY STILL BE CONSERVATIVE
CONSIDERING SOME OF THE HI-RES MODELS HAVE BEEN SHOWING THE
POTENTIAL FOR ISOLATED RAINFALL AMOUNTS OVER 5 INCHES TONIGHT...SO
THIS IS SOMETHING THAT CERTAINLY BEARS SOME WATCHING.
THROUGH THE REST OF THE SHORT TERM...THE LLJ AND SFC FRONT WILL
SLOWLY WORK EAST WITH TIME DURING THE MORNING ON FRIDAY...WITH BEST
RAINFALL CHANCES FOR ERN MN/WRN WI LIKELY COMING DURING THE MORNING
AS REMNANTS OF TONIGHTS ACTIVITY SHIFTS EAST. BACKED OFF SOME ON
POPS FRIDAY AFTERNOON...AS CAMS ARE FAIRLY SPARSE WITH ACTIVITY AS
WE LOOSE THE DEFINITION ON THE SFC FRONT...WHICH WILL COINCIDE WITH
A WEAKENING OF THE LLJ AS WE GET INTO SUBSIDENCE ASSOCIATED WITH THE
RIGHT ENTRANCE REGION OF THE UPPER JET WORKING ACROSS THE
INTERNATIONAL BORDER. WITH LESS ACTIVITY EXPECTED...ALSO BOOSTED
TEMPS A FEW DEGREES OUT IN WRN WI AS IT IS NOT LOOKING AS LIKELY FOR
FRIDAY TO BE DOMINATED BY CLOUDS AND RAIN AS WAS PREVIOUSLY
ANTICIPATED.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 325 PM CDT THU JUL 10 2014
AS WE PROGRESS THROUGH THE SATURDAY-THURSDAY PERIOD WE/LL SEE QUITE
THE EVOLUTION OF LARGE SCALE FEATURES AND WEATHER ACROSS THE AREA.
THINGS WILL START OUT WARM WITH THE UPPER JET NORTH OF THE AREA...
BUT AN UNSEASONABLY DEEP UPPER LOW WILL DROP SOUTH/EAST FROM CENTRAL
CANADA INTO THE UPPER MIDWEST AND GREAT LAKES REGION DURING THE
SUNDAY NIGHT THROUGH TUESDAY PERIOD. THIS WILL BRING VERY COOL
TEMPERATURES TO MUCH OF THE REGION... WITH THE HEART OF THE COLD AIR
TRACKING ACROSS MINNESOTA AND POINTS EAST. SOME PCPN CHANCES WILL
LOITER ACROSS THE REGION SATURDAY INTO SUNDAY PRIOR TO THE ARRIVAL
OF THE COLD FRONT AND UPPER TROUGH... WITH DIURNAL CHANCES FOR PCPN
AFTER THAT AS THE UPPER COLD POOL SWINGS ACROSS THE REGION. BEST
CHANCES FOR PCPN PRIOR TO FROPA WILL BE ACROSS THE SOUTHERN PORTIONS
OF THE AREA WHERE THE BAROCLINIC ZONE AND BEST INSTABILITY ARE
PROGGED... WITH CHANCES FOR DIURNAL SHRA FOLLOWING FROPA LOCATED
OVER EASTERN AREAS WHERE BOUNDARY LAYER CYCLONIC FLOW WILL BE MOST
PREVALENT AND LOW-MID LEVEL LAPSE RATES WILL BE STEEPEST BENEATH THE
MID-UPPER LEVEL COLD POOL. WE WILL SEE RIDGING BEGIN TO WORK INTO
THE AREA AFTER TUESDAY... WITH DRY WEATHER AND MODERATING
TEMPERATURES FOR THE LAST FEW DAYS OF THE FORECAST PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 649 PM CDT THU JUL 10 2014
INSTABILITY CONTINUES TO INCREASE ALONG AND WEST OF THE DAKOTAS/MN
BORDER EARLY THIS EVENING AS A SHORT WAVE MOVES INTO THE CENTRAL
DAKOTAS. SHOWERS ARE INCREASING IN COVERAGE AND INTENSITY OVER
EASTERN SOUTH DAKOTA. THIS SHOULD LEAD TO THUNDERSTORMS BECOMING
LIKELY EARLY THIS EVENING FOR KAXN AND DURING THE LATE EVENING FOR
KRWF. IT WILL PROBABLY BE CLOSER TO MIDNIGHT BEFORE THUNDER
REACHES KSTC. SHORT TERM GUIDANCE POINTS TO THE ACTIVITY REACHING
THE TWIN CITIES BEFORE DAYBREAK WITH WEAKENING AS IT PUSHES ACROSS
WEST CENTRAL WI. HOWEVER...MORE DEVELOPMENT IS SHOWN ACROSS EASTERN
MN LATER IN THE MORNING. AN UNSETTLED PERIOD FOR SURE. MAINLY VFR
BUT BOUTS OF MVFR OR LOWER ARE CERTAINLY LIKELY IN THE HEAVIER
STORMS. CONCERN IS ALSO INCREASING FOR MVFR CEILINGS DEVELOPING
FRIDAY AFTERNOON FROM KSTC AND KMSP ON EAST IN THE MOIST
SOUTHERLY FLOW AHEAD OF AN APPROACHING COLD FRONT IN THE EASTERN
DAKOTAS. CONFIDENCE IS NOT HIGH AT THIS TIME WITH BKN-OVC050
INSERTED. SOUTHERLY WINDS (170-210) NEAR 10 KNOTS THROUGH THE
PERIOD.
KMSP...SOME SPRINKLES ARE CERTAINLY POSSIBLE LATER THIS EVENING
WITH MORE ROBUST SHOWERS AND THUNDERSTORMS EXPECTED IN THE 08Z-12Z
TIME FRAME. SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL LIKELY
LINGER THROUGH THE MORNING. A FEW SHOWERS AND THUNDERSTORMS ARE
POSSIBLE FRIDAY EVENING AHEAD OF AN APPROACHING COLD FRONT.
/OUTLOOK FOR KMSP/
SAT...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WIND NW AT 5 KTS.
SUN...VFR WITH MVFR/SHRA/TSRA POSSIBLE. WINDS W AT 5-10 KTS.
MON...VFR WITH MVFR CIGS/SHRA POSSIBLE. WIND NW AT 10-20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...TRH
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1151 PM CDT TUE JUL 8 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 302 PM CDT TUE JUL 8 2014
LOOKS A QUIET SHORT TERM WITH COOL NORTHWEST FLOW AND BELOW NORMAL
TEMPERATURES TONIGHT AND TOMORROW. SCATTERED SHOWERS AND WEAK
THUNDERSTORMS OVER WI ARE LOCATED IN AN AREA OF STRONGER COLD
ADVECTION AND OUT AHEAD OF A SUBTLE SHORTWAVE FEATURE DROPPING SOUTH
ACROSS MN AND WI. THERE IS A SECOND PV ANOMALY IN SD WITH TALLER
CUMULUS CLOUDS IN EASTERN SD AND WESTERN MN...BUT THE SHOWER
ACTIVITY HAS REMAINED MUCH MORE SPARSE UP TO THIS POINT. VISIBLE
SATELLITE ALSO SHOWS A HEALTHY AMOUNT OF SMOKE DROPPING SOUTH ACROSS
THE DAKOTAS THIS AFTERNOON...WHICH MIGHT MAKE FOR A COLORFUL SUNSET
THIS EVENING...ESPECIALLY FOR THOSE IN WESTERN MN WHO ARE CLOSER TO
THE EDGE OF THE SMOKE. THE SMOKE IS BEING ADVECTED SOUTH FROM
WILDFIRES IN CANADA...MOST LIKELY FROM WHAT IS BURNING IN THE
NORTHWEST TERRITORIES. SATELLITE SHOWED A THICK LAYER OF SMOKE IN
ALBERTA AND SASKATCHEWAN AT THIS TIME YESTERDAY. THE ATMOSPHERIC
COLUMN CONTINUES TO DRY FROM WHAT WAS PRESENT ON SUNDAY/MONDAY...THE
LAST COUPLE MPX SOUNDINGS HAVE SHOWN PWATS OF 1.25" AND 0.90"
RESPECTIVELY AND THE EARLY AFTERNOON RAP ANALYSES ARE HOVERING RIGHT
AROUND 0.75". THERE IS AN OBVIOUS REDUCTION IN SURFACE MOISTURE
TODAY...WITH DEWPOINTS COMFORTABLY IN THE 50S. NOT MUCH ELSE GOING
ON IN THE SHORT TERM WITH A SURFACE HIGH SETTLING IN FOR TOMORROW.
WITH THE HIGH OVERHEAD...MN/WI WILL BE OUT OF THE BEST PRESSURE
GRADIENT AND WILL SEE LIGHTER WINDS TOMORROW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 302 PM CDT TUE JUL 8 2014
THE MAIN THEME THROUGH THE LATTER PORTION OF THE FORECAST WILL BE
A RE-AMPLIFICATION OF THE UPPER AIR PATTERN INTO THAT ALL TOO
FAMILIAR CONFIGURATION WE/VE SEEN FOR MUCH OF THE PAST 9 MONTHS.
FOR US THAT MEANS AFTER SOME BRIEF MODIFICATION OF TEMPERATURES
DURING THE SECOND HALF OF THIS WEEK WE/LL SEE THINGS COOL OFF
SUBSTANTIALLY AS WE MOVE TOWARD THE START OF NEXT WEEK. IN THE
DETAILS... PCPN CHANCES LOOK TO RETURN FROM WEST TO EAST THURSDAY
AND THURSDAY NIGHT AS THE SURFACE HIGH SHIFTS EAST AND WARM
ADVECTION COMMENCES OVER THE AREA. IT THEN APPEARS WE/LL NEED TO
INCLUDE CHANCE POPS FOR MUCH OF THE TIME FRAME THROUGH AT LEAST
SATURDAY AS THE BAROCLINIC ZONE LINGERS IN THE AREA AND WE SEE
PERIODIC WEAK DISTURBANCES MOVE THROUGH THE FLOW AND ACROSS OUR
AREA. MUCH COOLER TEMPERATURES LOOK TO RETURN BY SUNDAY OR MONDAY
AS THE EASTERN TROUGH SIGNIFICANTLY AMPLIFIES. THIS SHOULD BRING
DRIER AIR INTO THE REGION AS THE UPPER JET IS DISPLACED
SOUTHWARD... ALTHOUGH SUNSHINE DURING THIS TIME OF YEAR COULD
CERTAINLY LEAD TO SOME DIURNAL PCPN IF WE HAVE SUFFICIENT CYCLONIC
FLOW AND EKMAN PUMPING IN THE BOUNDARY LAYER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1138 PM CDT TUE JUL 8 2014
VFR CONDITIONS EXPECTED. THINK FOG POTENTIAL IS LOW TONIGHT DUE
TO DRIER AIR MOVING IN...BUT IT CANNOT BE COMPLETELY RULED OUT AT
EAU DUE TO THE RIVER NEARBY. BIGGEST CONCERN FOR THE PERIOD WILL
BE SMOKE INVADING THE NORTHERN PLAINS LATE THIS EVENING. THIS MAY
BRING MINOR REDUCTIONS IN SFC VISIBILITY IF MIXING CAN REACH DEEP
ENOUGH WEDNESDAY ALONG WITH MILKY SKY COVER AS THE LARGE SMOKE
PLUME FROM CANADA ADVANCES EASTWARD.
KMSP...NO MAJOR CONCERNS OTHER THAN STATED ABOVE.
/OUTLOOK FOR KMSP/
THU...VFR. MVFR POSSIBLE IN SHRA/TS LATE. SSE WIND 10 TO 15 KT.
FRI...MVFR CONDITIONS POSSIBLE WITH A CHANCE OF SHRA/TSRA. SOUTH
WIND 5 TO 10 KT.
SAT...VFR. SGT CHC OF SHRA/TSRA. NORTH WIND 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
905 PM MDT Thu Jul 10 2014
.DISCUSSION...
Update forthcoming. Lingering monsoonal moisture, along with
atmospheric instability along the southwest Montana/Idaho border, is
allowing isolated thunderstorms to continue. However, the moisture
source is beginning to decrease and convective activity should
further decrease with the loss of daytime heating. Have scaled back
the POP field through midnight, keeping POPs over extreme south and
southeast Montana. Have scaled back POPs even further after
midnight. In the north, circulation around an upper low centered
over western Saskatchewan is pushing moisture into an unstable
airmass and across the Canadian prairie. This moisture has combined
with a cold front moving south and the result is the development of
isolated thunderstorms. Satellite imagery indicates a strong
thunderstorm moving east-southeast across southern Alberta at this
time. RUC model data and HRRR analysis want to bring the core of
this storm south of the international border after 05z, affecting
areas along the Hi-Line. Have gone with low POPs across the northern
portion of the county warning area for this reason, bringing the threat
as far south as Lewistown and as far west as Great Falls per the
RUC. Temperatures look reasonable.
&&
.AVIATION...
UPDATED 2335Z.
VFR conditions will continue across north central, central, and
southwest Montana at least through the day on Friday. Skies will
remain partly cloudy across the area through at least 06Z, with only
isolated thunderstorms possible along the SW Montana/NE Idaho
border, well south of the KBZN terminal. Moisture wrapping around a
low pressure system in central Canada combined with a weak cold
front moving into the area from the north between 06Z and 18Z. This
will bring increasing mid level cloudiness with isolated
showers/thunderstorms to much of north central (KCTB KHVR) and
central (KGTF KLWT) Montana. Have only mentioned VCSH in the TAFs at
this time, as am thinking that the chance for thunderstorms is lower
than the chance for showers due to this occurring during a
climatologically less unstable timeframe. However, will monitor
shower/storm development through 06Z for further potential updates.
Clouds/showers/storms will decrease after 18Z as the system exits
the area. However, monsoonal moisture will move back into southwest
Montana (including KBZN) after 18Z, bringing a chance of
thunderstorms there.
Coulston
&&
.PREV DISCUSSION...Issued 242 PM MDT Thu Jul 10 2014
Thursday through Saturday...Hot and dry conditions will continue
as the slowly moving large scale ridge continues to be dominant
force in the weather pattern over much of the Western United States.
Will continue to remain in a transition period on the edge of the
ridge through at least the next 24 hours. This will allow for
showers to develop as moisture allows. The best chance will be
with afternoon heating over the Mountains of Southwest Montana and
across the highline Thursday Evening as a weak disturbance moves
across the northern counties. By Friday a slight increase in
available moisture will allow for more showers and thunderstorms
to develop with afternoon heating...however showers will likely be
limited to scattered at best coverage. Another round of showers
will again occur on Saturday during peak heating mainly over the
higher terrain. Suk
Saturday night through Thursday...An upper level ridge high
pressure will be over the region this weekend...then the upper level
ridge will shift westward on Monday...as a fairly strong upper level
low pressure over the Great Lakes area rotates a bit cooler air into
the region. As the upper level low over the Great Lakes begins to
move eastward on Tuesday...the upper level ridge will also start to
shift back eastward for Tuesday afternoon through Thursday. Thus
fairly warm temperatures are expected for Sunday...then seasonable
temperatures for Monday and Tuesday...with a return to slightly
above normal temperatures for Wednesday and Thursday. In terms of
precipitation...confidence is quite low on any one given day...thus
most days the chances for thunderstorms are fairly isolated. The
best time frame for any storms to occur will be late afternoon
through around Midnight...but again the thunderstorm activity should
be fairly isolated and not have significant impacts on any one given
day. Brusda
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 54 78 54 86 / 20 10 10 10
CTB 51 75 50 84 / 20 10 10 10
HLN 58 84 58 88 / 10 10 20 20
BZN 53 83 54 83 / 10 30 20 40
WEY 44 79 44 76 / 30 50 40 50
DLN 54 84 55 83 / 10 20 20 40
HVR 56 80 53 88 / 20 20 10 10
LWT 54 78 53 84 / 20 20 20 20
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
www.twitter.com/NWSGreatFalls
www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1030 PM MDT Tue Jul 8 2014
update aviation section...
.UPDATE...
Current satellite imagery and regional webcams show mix of clear
to partly cloudy skies this evening as pockets of moisture move
through the high pressure ridge covering the western states. Of
note, water vapor satellite imagery indicates that a displaced band
of the monsoonal moisture plume expected to arrive tomorrow has
already made it into east-central Idaho and produced a few light
showers near Monida Pass around 8pm. The Rapid Update Cycle (RUC)
forecast model has been the only model to pick up on this feature at
this point in time, with other models showing dry conditions from
central Idaho northward. But even the RUC paints only a minimal
chance of additional light and spotty showers along the ID/MT border
thru the overnight hours, so will continue with a dry forecast for
tonight across the region.
Main portion of the monsoonal plume currently extends from central
NV to northern OR and is beginning to show a turn to east in
response to high pressure ridge axis slowly drifting into western
MT. Forecast still on track for the main plume to move into
southwest MT tomorrow aftn and portions of central MT tomorrow
evening, bringing isolated thunderstorms with generally less than
0.1 inch of precipitation where rainfall occurs.
Waranauskas
&&
.DISCUSSION...
Tonight through Thursday...High pressure will remain over Central
Montana into Wednesday when monsoonal moisture will sneak into the
region from the southwest. This increased moisture should be
enough to allow afternoon thunderstorms to develop over Southwest
Montana Wednesday afternoon. Things look to quiet down again on
Thursday with only an isolated chance of a shower over Southwest
Montana. Temperatures will largely remain unchanged day to day
with mid to upper 80s, and some 90s, across much of the region.
Winds look to remain light overall with some breeziness across the
plains Wednesday and Thursday.
Thursday night through Tuesday...Overall an upper level ridge of
high pressure will continue to reside over the Pacific Northwest
through the period. The upper level ridge will try to flatten a bit
at times...or retrograde a bit westward...however the main impact
weather-wise for our region will be warm temperatures and the chance
for a passing thunderstorm. For precipitation...confidence is
quite low in timing and amounts of any precipitation during the
extended period...thus generally kept isolated to scattered
thunderstorms over the region. Brusda
Some temperature discrepancies arise in the Monday-Tuesday time
period between the GFS and EC. Both models indicate a highly
amplified ridge persisting over the Western U.S. and Western Canada.
The EC forecasts a deeper and larger-scale upper level low
forming in the Hudson Bay and Great Lakes region...large enough to
bring cooler air into eastern and central Montana via E/NE winds.
1000-500mb thicknesses peak around 582 dm on Sunday and Monday per
the GFS with EC values around 576 dm. 850 temps on the GFS are in
the mid to upper 20s C through Monday while the EC is approximately
5 C cooler.
By Tuesday...thickness values drop to near 573 dm on the GFS and to
567-570 on the EC. Both models show a 850 mb temp drop to near 20
C. Given the lower confidence went with a blended approach on
Tuesday with highs in the low 80s. The slight cool down will likely
be short lived with model guidance pushing the mid level ridge axis
eastward into the middle/end of next week. Uttech
&&
.AVIATION...
UPDATED 0430Z.
VFR conditions will prevail through this TAF period with relatively
light winds and mostly clear skies through 18Z on Wednesday
afternoon. A disturbance and some moisture from the southwest will
affect southwest Montana in the afternoon. This will bring more
clouds and isolated afternoon thunderstorms. Most will have high
bases and give the potential for gusty winds and localized rainfall.
MVFR conditions expected in thunderstorms, otherwise VFR to prevail.
Some wind gusts to 20kts expected in the afternoon, expecially
around KCTB. db
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 57 91 59 89 / 0 0 20 0
CTB 55 89 55 83 / 0 0 20 10
HLN 60 93 61 93 / 0 10 20 0
BZN 53 90 55 90 / 0 20 20 10
WEY 44 82 45 81 / 0 40 30 30
DLN 57 87 55 88 / 0 30 20 20
HVR 54 93 60 88 / 0 0 20 10
LWT 55 88 59 87 / 0 10 20 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
www.twitter.com/NWSGreatFalls
www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
321 PM CDT WED JUL 9 2014
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 319 PM CDT WED JUL 9 2014
MODELS IN RELATIVELY DECENT AGREEMENT LARGE SCALE FLOW OVER MOST OF
THE CONUS WILL BE NEAR ZONAL WHILE A POTENT SHORTWAVE TROF RUSHES
ACROSS CANADA. HEADING INTO THE WEEKEND THEN...PATTERN IS PROGGED TO
BEGIN AMPLIFYING WITH AN UPSTREAM RIDGE BECOMING ESTABLISHED OVER
THE WRN CONUS BY SAT AFTN. MEANWHILE...GULF MOISTURE ADVECTION WILL
BEGIN IN EARNEST LATER TONIGHT AS SFC HIGH PRESSURE SLIDES EAST AND
ALLOWS MOISTURE TO SLIDE UP ALONG THE WRN HIGH PLAINS. APPEARS THAT
MOISTURE RICH ENVIRONMENT WILL BE IN PLACE THEN THRU THE FCST PD.
CURRENT RADAR MOSAIC WAS SHOWING CLUSTER OF TSTMS FROM S-CNTRL SD
INTO N-CNTRL NEB MOVING SE WITHIN POCKET OF MID LYR ISENTROPIC
UPGLIDE. LATEST HRRR SUGGESTING AREA OF CONVECTION WILL GRADUALLY
INCREASE IN AREAL COVERAGE AND EXPAND INTO THE WRN CWA THEN EARLY
THIS EVENING AND POSSIBLY THE REST OF THE CWA OVERNIGHT.
OTHERWISE...MAIN ISSUE IS PINNING DOWN PLACEMENT/TIMING THUNDER POPS
THE NEXT COUPLE DAYS. HOWEVER...REASONABLE ASSUME ON THUR NIGHT/FRI
NIGHT...LLVL JET AND FAVORABLE FRONTOGENETIC FORCING/THETA-E CONVG
WITHIN BNDRY LYR WILL HELP INDUCE NOCTURNAL TSTM ACTIVITY. AS FOR
SVR TSTMS...NAM IS ADVERTISING POSSIBLE SVR DEVELOPMENT THUR NIGHT
OVER N-CNTRL NEB WITH MUCAPES 2000-2500 J/KG AND ADEQUATE VERTICAL
SHEAR. ALL THIS IN PART TO LEESIDE SFC LOW AND ATTENDANT THERMAL
BNDRY EXTENDING FROM ABOUT NERN CO TO NERN SD. GFS INSTABILITY/SHEAR
AT THAT TIME THOUGH IS SUBSTANTIALLY WEAKER.
NEVERTHELESS...SITUATION BEARS WATCHING.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM CDT WED JUL 9 2014
RATHER GOOD AGREEMENT BTWN CMC/ECM/GFS EARLY ON THAT AMPLIFICATION
WILL CONTINUE INTO EARLY NEXT WEEK WITH A HIGHLY ANOMALOUS UPPER
TROF OVER THE ERN CONUS AND UPSTREAM RIDGE OVER THE WRN CONUS. AT
THIS POINT DETERMINISTIC ECM/GFS AS WELL AS ECMENS/CMCENS ALL
INDICATE LARGE SCALE FLOW WILL BECOME STAGNANT AND ALLOW A RATHER
COOL AIRMASS FOR THIS TIME OF THE SEASON TO EXPAND SWD INTO THE
REGION DAY 6 AND 7. EXPECT THEN A GOOD CHUNK OF THE CNTRL PLAINS
WILL SEE WELL BELOW NORMAL AFTN TEMPS TUES AND WED. GOING POPS IN
THE EXT PDS LOOK GOOD FOR NOW SO NO MAJOR CHANGES PLANNED.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1256 PM CDT WED JUL 9 2014
VFR CONDITIONS ARE FORECAST TO CONTINUE ACROSS THE FORECAST AREA
THROUGH THE PERIOD. THE ONE AREA THAT MAY HAVE MVFR CEILINGS IS
THE KLNK AREA SHRA AND TSRA IS POSSIBLE IN KLNK AFTER 00Z AND
WOULD BE IN THE STRONGER CELLS. SMOKE PLUME FROM FIRES IN CANADA
ARE EXTENDING SOUTHWARD INTO THE MISSOURI RIVER VALLEY IN NEBRASKA
AND IOWA. ASIDE FROM SLIGHTLY HAZY SKY CONDITIONS...THIS IS NOT
EXPECTED TO HAVE AN IMPACT ON VISIBILITIES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...DEE
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
318 PM CDT WED JUL 9 2014
.SYNOPSIS...
ISSUED AT 318 PM CDT WED JUL 9 2014
H5 ANALYSIS FROM THIS MORNING HAS A CONTINUATION OF THE
RIDGE/TROUGH REGIME ACROSS THE CONUS. A TROUGH OF LOW PRESSURE
EXTENDED SOUTH FROM NORTHERN CANADA INTO THE OHIO VALLEY. RIDGING
EXTENDED NORTH FROM HIGH PRESSURE LOCATED OVER SRN UTAH INTO
NORTHERN PORTIONS OF ALBERTA AND SASKATCHEWAN. ACROSS THE CENTRAL
AND NORTHERN PLAINS...A NICE 40 TO 45 KT SPEED MAX EXTENDED FROM
WESTERN NEBRASKA NWD INTO WESTERN SD AND MT. THIS FEATURE ALONG WITH
A VERY WEAK CAP...HAS SUPPORTED CONVECTION ACROSS NORTHERN AND
EASTERN PORTIONS OF THE FORECAST AREA THIS MORNING AND THIS
AFTERNOON. SO FAR...STORMS HAVE LARGELY REMAINED BELOW SEVERE LIMITS
THROUGH THE MORNING...HOWEVER...WITH INCREASED HEATING THIS
AFTERNOON...STORMS HAVE INCREASED IN STRENGTH GIVEN THE DECENT
DEGREE OF BULK SHEAR. AS OF 3 PM CDT...UNDER PARTLY TO MOSTLY
CLOUDY SKIES...TEMPERATURES RANGED FROM 62 IN RAIN COOLED AIR AT
AINSWORTH...TO 90 AT IMPERIAL.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 318 PM CDT WED JUL 9 2014
TONIGHT AND THURSDAY...PRECIPITATION CHANCES TONIGHT
AND TOMORROW AFTERNOON ARE THE MAIN FORECAST CONCERNS. FOR
TONIGHT...THUNDERSTORM CHANCES WILL CONTINUE THROUGH LATE EVENING
AND MAY POSSIBLY CONTINUE INTO THE OVERNIGHT WITH THE PRESENCE OF A
LOW LEVEL JET ANCHORED ACROSS SOUTHERN NEBRASKA. ATTM CONFIDENCE IN
PCPN PERSISTING INTO THE OVERNIGHT IS NOT HIGH ATTM AS THE NAM SOLN
IS A TAD FARTHER EAST WITH ITS LOW LEVEL JET AND THE HRRR SOLN
PUSHES THIS ACTIVITY SOUTH OF THE AREA BY LATE EVENING. THURSDAY
MORNING WILL BE QUIET ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA...HOWEVER...BY THURSDAY AFTERNOON...SURFACE HEATING AND THE
APPROACH OF AN UPPER LEVEL DISTURBANCE...WILL STEEPEN LAPSE RATES
ACROSS THE WESTERN FORECAST AREA BY 21Z THURSDAY. H85 TO H7 LAPSE
RATES WILL APPROACH 9.5 TO 10C THURSDAY AFTERNOON. IN ADDITION...THE
CAP WILL WEAKEN INVOF A SURFACE TROUGH MID AFTERNOON THURSDAY.
ATTM...THUNDERSTORMS ARE EXPECTED TO INITIATE MID AFTERNOON IN THE
PANHANDLE AND TRACK EAST. ATTM...WILL CONFINE PRECIP CHANCES TO THE
WESTERN HALF OF THE FORECAST AREA...AS LOCATIONS IN THE EAST ARE
STRONGLY CAPPED THURSDAY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 318 PM CDT WED JUL 9 2014
THURSDAY NIGHT THROUGH SATURDAY NIGHT...THE MAIN FORECASTING
CHALLENGE CONTINUES TO BE PRECIPITATION CHANCES AS THE FORECAST AREA
REMAINS IN NORTHWESTERLY AND WEST NORTHWESTERLY FLOW ALOFT. A
FRONTAL BOUNDARY WILL PUSH SOUTH ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA THURSDAY NIGHT AND WILL BE THE FOCUS FOR SHOWER AND
THUNDERSTORM DEVELOPMENT THURSDAY NIGHT INTO FRIDAY MORNING. STRONG
STORMS WILL BE POSSIBLE INVOF THE FRONT THURSDAY EVENING...WITH 35
TO 45 KTS OF DEEP LAYER SHEAR THURSDAY EVENING. INTO THE OVERNIGHT
HOURS...A STRONG LOW LEVEL JET EXTENDING FROM SWRN NEBRASKA INTO
NERN NEBRASKA...WILL ALLOW THE THREAT FOR STORMS TO
CONTINUE...HOWEVER...THE THREAT FOR SEVERE STORMS WILL DIMINISH AS
DEEP LAYER SHEAR DECREASES TO 20 TO 30 KTS OVERNIGHT. ON
FRIDAY...THE FRONT WILL STALL EITHER IN SOUTHWESTERN KS TO SERN
NEBRASKA PER THE NAM SOLN OR FROM NWRN KS INTO SOUTH CENTRAL
NEBRASKA PER THE GFS SOLN. THE GFS GENERATES A NICE AREA OF POST
FRONTAL MID LEVEL LIFT NORTH OF THE FRONT ACROSS CENTRAL AND
NORTHERN NEBRASKA FRIDAY AFTERNOON INTO FRIDAY NIGHT...WHILE THIS IS
LARGELY ABSENT IN THE NAM SOLN. EVEN WITH A MODEL COMPROMISE AND THE
FRONT ACROSS NORTHERN KS...DECENT MID LEVEL LIFT AND WARM AIR
ADVECTION NORTH OF THE FRONT ACROSS THE FORECAST AREA PER THE GFS SOLN IS
HARD TO IGNORE. WITH THIS IN MIND...WILL CONTINUE POPS FRIDAY
AFTERNOON INTO FRIDAY NIGHT. ON SATURDAY...THE FRONT WILL WASH
OUT...ALLOWING SRLY WINDS TO SURGE NORTH INTO THE PANHANDLE. THETA E
RIDGING AND INCREASED MOISTURE WILL BUILD NORTH INTO THE PANHANDLE
AS WELL LEADING TO 1500 TO 2500 J/KG CAPES SATURDAY AFTERNOON.
THUNDERSTORMS SHOULD INITIATE QUICKLY LATE SAT AFTERNOON...WITHIN A
WEAKLY CAPPED AREA IN THE PANHANDLE AND WESTERN SANDHILLS. THIS
ACTIVITY WILL TRANSITION EAST SAT EVENING AND HAS THE POTENTIAL TO
BE SEVERE WITH FCST DEEP LAYER SHEAR OF 40 TO 50 KTS.
SUNDAY THROUGH WEDNESDAY...A STRONG UPPER LEVEL LOW OVER THE HUDSON
BAY WILL DROP SOUTH INTO WESTERN ONTARIO. THIS WILL FORCE A STRONG
NRN STREAM COLD FRONT INTO THE REGION SUNDAY AFTERNOON INTO SUNDAY
NIGHT. THUNDERSTORMS MAY DEVELOP ALONG AND BEHIND THIS FEATURE
SUNDAY AND SUNDAY NIGHT AND WILL SHIFT SOUTH BY MONDAY MORNING. HIGH
AMPLITUDE NORTHWESTERLY FLOW ALOFT WILL DEVELOP ACROSS THE HIGH
PLAINS MONDAY. ANY STORMS WHICH DO FIRE TO THE WEST UNDERNEATH THE
THETA E AXIS...SHOULD STAY MAINLY OFF TO THE WEST OF THE FORECAST
AREA GIVEN THE NWRLY STEERING WINDS. WITH THIS IN MIND...WILL KEEP
THE HIGHEST POPS IN THE PANHANDLE AND FAR SOUTHWEST. MUCH COOLER
TEMPERATURES WILL DEVELOP BEHIND THE FRONT WITH 70S FOR HIGHS
TUESDAY AND WEDNESDAY OF NEXT WEEK AND POPS GENERALLY CONFINED TO
THE HIGHER TERRAIN OF COLORADO AND SERN WYOMING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1227 PM CDT WED JUL 9 2014
THUNDERSTORMS...POSSIBLY SEVERE...ARE EXPECTED TODAY ACROSS MUCH
OF WESTERN AND NORTH CENTRAL NEBRASKA LATE THIS AFTERNOON AND
EVENING. THE CONVECTIVE ALLOWING MODELS CONTINUE TO INDICATE
FURTHER DESTABILIZATION OF THE ATMOSPHERE THIS AFTERNOON...WITH A
CONVECTIVE CLUSTER/S FORMING INVOF THE SANDHILLS REGION AND/OR SW
NEBRASKA AND MOVING SOUTHEAST THIS EVENING. LARGE HAIL AND GUSTY
ERRATIC WIND WOULD BE EXPECTED WITHIN OR NEAR ANY STORM. OTHERWISE
WERE WATCHING STORMS THAT MAY IMPACT KVTN OR KANW EARLY THIS
AFTERNOON...THESE STORMS WILL BE STRONG...WITH THE POTENTIAL OF
HAIL...BRIEF VISIBILITY RESTRICTIONS AND GUSTY WIND. CONDITIONS WILL
QUIET THIS EVENING...BUT SOUTHERLY TO SOUTHEASTERLY WINDS AOA
10KTS CAN BE EXPECTED THROUGH THE REMAINDER OF THE FORECAST
PERIOD.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...CLB
AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
146 PM CDT WED JUL 9 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 307 AM CDT WED JUL 9 2014
NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE REGION IN BETWEEN AN
UPPER RIDGE AXIS OVER THE WESTERN CONUS AND AN AMPLIFIED TROUGH
OVER THE EASTERN CONUS. SFC HIGH PRESSURE CONTINUES TO MOVE
OVERHEAD WITH WEAK RETURN FLOW PROGGED TO SET UP EARLY THIS
AFTERNOON. LIGHT WINDS AND INCREASING CLOUD COVER SHOULD LIMIT
HIGHS TO THE UPPER 70S TO AROUND 80 TODAY. YESTERDAY`S VISIBLE
SATELLITE IMAGERY SHOWED AN EXTENSIVE SMOKE PLUME STRETCHING
SOUTHEAST FROM CANADIAN FIRES INTO THE DAKOTAS. IF THICK
ENOUGH...THIS COULD LIMIT TEMPS TODAY AS WELL BUT THAT IS TOUGH TO
DETERMINE AT THIS POINT. THE RECENT RUNS OF THE HRRR AND RAP DO
INDICATE AN AREA OF PCPN DEVELOPING ACROSS THE HIGH PLAINS EARLY
THIS MORNING IN RESPONSE TO A QUICK MOVING IMPULSE DROPPING
THROUGH NORTHWEST FLOW. THIS IMPULSE IS FORECAST TO CONTINUE TO
SLIDE SOUTHEAST ACROSS CENTRAL NEBRASKA AND INTO OUR SOUTHWESTERN
CWA BY THIS AFTERNOON. INSTABILITY LOOKS WEAK THIS AFTERNOON AND
SO THINK SCATTERED SHOWERS WITH A FEW ISOLATED TSTMS COULD DEVELOP
OVER OUR WESTERN CWA AS EARLY AS MID TO LATE AFTERNOON AND
CONTINUE TO STRENGTHEN INTO THE EVENING AND OVERNIGHT HOURS AS
NOSE OF MODEST LLVL JET SHIFTS EASTWARD.
A BIT OF A BREAK IN ACTIVITY IS EXPECTED DURING THE DAY THURSDAY
WHILE STRONG THETA-E ADVECTION BRINGS JULY MOISTURE BACK INTO THE
REGION. ELONGATED SFC LOW PRESSURE WILL EXTEND ACROSS THE HIGH
PLAINS OF WYOMING AND COLORADO WITH STRONG SOUTHERLY FLOW OUT
AHEAD OF IT. BEST CHANCES FOR TSTMS WILL AGAIN BE NOCTURNAL AS THE
NOSE OF STRENGTHENING LLVL JET ADVECTS EAST. THIS COMBINED WITH
STEEPENING MID LEVEL LAPSE RATES SHOULD AID IN ELEVATED TSTMS
ACROSS THE CWA. THE SFC LOW WILL BEGIN TO SLOWLY DRIFT INTO THE
CNTRL PLAINS FRIDAY...PLACING A BOUNDARY ACROSS THE KS/NEB BORDER
BY FRIDAY NIGHT.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 307 AM CDT WED JUL 9 2014
ROUNDS OF NOCTURNAL THUNDERSTORMS ARE LIKELY THROUGH THE WEEKEND AS
A SERIES OF WEAK MID LEVEL IMPULSES DRIFT ACROSS THE CENTRAL PLAINS.
IT IS HARD TO RULE OUT ANY ONE PARTICULAR PERIOD SO HAVE LEFT SMALL
POPS IN FOR MUCH OF THE WEEKEND...ALTHOUGH WE DO NOT ANTICIPATE
CONTINUOUS ACTIVITY. A STRONG COLD FRONT IS PROGGED TO DROP INTO THE
AREA LATE MONDAY/TUESDAY BRINGING BELOW NORMAL TEMPERATURES TO THE
REGION TUESDAY AND WEDNESDAY.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1256 PM CDT WED JUL 9 2014
VFR CONDITIONS ARE FORECAST TO CONTINUE ACROSS THE FORECAST AREA
THROUGH THE PERIOD. THE ONE AREA THAT MAY HAVE MVFR CEILINGS IS
THE KLNK AREA SHRA AND TSRA IS POSSIBLE IN KLNK AFTER 00Z AND
WOULD BE IN THE STRONGER CELLS. SMOKE PLUME FROM FIRES IN CANADA
ARE EXTENDING SOUTHWARD INTO THE MISSOURI RIVER VALLEY IN NEBRASKA
AND IOWA. ASIDE FROM SLIGHTLY HAZY SKY CONDITIONS...THIS IS NOT
EXPECTED TO HAVE AN IMPACT ON VISIBILITIES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
700 AM CDT WED JUL 9 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 307 AM CDT WED JUL 9 2014
NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE REGION IN BETWEEN AN
UPPER RIDGE AXIS OVER THE WESTERN CONUS AND AN AMPLIFIED TROUGH
OVER THE EASTERN CONUS. SFC HIGH PRESSURE CONTINUES TO MOVE
OVERHEAD WITH WEAK RETURN FLOW PROGGED TO SET UP EARLY THIS
AFTERNOON. LIGHT WINDS AND INCREASING CLOUD COVER SHOULD LIMIT
HIGHS TO THE UPPER 70S TO AROUND 80 TODAY. YESTERDAY`S VISIBLE
SATELLITE IMAGERY SHOWED AN EXTENSIVE SMOKE PLUME STRETCHING
SOUTHEAST FROM CANADIAN FIRES INTO THE DAKOTAS. IF THICK
ENOUGH...THIS COULD LIMIT TEMPS TODAY AS WELL BUT THAT IS TOUGH TO
DETERMINE AT THIS POINT. THE RECENT RUNS OF THE HRRR AND RAP DO
INDICATE AN AREA OF PCPN DEVELOPING ACROSS THE HIGH PLAINS EARLY
THIS MORNING IN RESPONSE TO A QUICK MOVING IMPULSE DROPPING
THROUGH NORTHWEST FLOW. THIS IMPULSE IS FORECAST TO CONTINUE TO
SLIDE SOUTHEAST ACROSS CENTRAL NEBRASKA AND INTO OUR SOUTHWESTERN
CWA BY THIS AFTERNOON. INSTABILITY LOOKS WEAK THIS AFTERNOON AND
SO THINK SCATTERED SHOWERS WITH A FEW ISOLATED TSTMS COULD DEVELOP
OVER OUR WESTERN CWA AS EARLY AS MID TO LATE AFTERNOON AND
CONTINUE TO STRENGTHEN INTO THE EVENING AND OVERNIGHT HOURS AS
NOSE OF MODEST LLVL JET SHIFTS EASTWARD.
A BIT OF A BREAK IN ACTIVITY IS EXPECTED DURING THE DAY THURSDAY
WHILE STRONG THETA-E ADVECTION BRINGS JULY MOISTURE BACK INTO THE
REGION. ELONGATED SFC LOW PRESSURE WILL EXTEND ACROSS THE HIGH
PLAINS OF WYOMING AND COLORADO WITH STRONG SOUTHERLY FLOW OUT
AHEAD OF IT. BEST CHANCES FOR TSTMS WILL AGAIN BE NOCTURNAL AS THE
NOSE OF STRENGTHENING LLVL JET ADVECTS EAST. THIS COMBINED WITH
STEEPENING MID LEVEL LAPSE RATES SHOULD AID IN ELEVATED TSTMS
ACROSS THE CWA. THE SFC LOW WILL BEGIN TO SLOWLY DRIFT INTO THE
CNTRL PLAINS FRIDAY...PLACING A BOUNDARY ACROSS THE KS/NEB BORDER
BY FRIDAY NIGHT.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 307 AM CDT WED JUL 9 2014
ROUNDS OF NOCTURNAL THUNDERSTORMS ARE LIKELY THROUGH THE WEEKEND AS
A SERIES OF WEAK MID LEVEL IMPULSES DRIFT ACROSS THE CENTRAL PLAINS.
IT IS HARD TO RULE OUT ANY ONE PARTICULAR PERIOD SO HAVE LEFT SMALL
POPS IN FOR MUCH OF THE WEEKEND...ALTHOUGH WE DO NOT ANTICIPATE
CONTINUOUS ACTIVITY. A STRONG COLD FRONT IS PROGGED TO DROP INTO THE
AREA LATE MONDAY/TUESDAY BRINGING BELOW NORMAL TEMPERATURES TO THE
REGION TUESDAY AND WEDNESDAY.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 700 AM CDT WED JUL 9 2014
GENERALLY EXPECT VFR CONDITIONS THROUGH THE PERIOD. LATEST RUNS OF
THE HRRR AND RAP13 MODEL SHOW THAT SOME -SHRA/-TSRA COULD MAKE IT
TO NEAR KOFK AND KLNK BY MID AFTERNOON AS ELEVATED INSTABILITY AND
MOISTURE WORK THEIR WAY EAST. 06Z NAM ALSO SUGGESTS THAT COULD
OCCUR. SMALL CHANCES CONTINUE INTO THE EVENING... ESPECIALLY FOR
KLNK.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
348 AM CDT WED JUL 9 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 307 AM CDT WED JUL 9 2014
NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE REGION IN BETWEEN AN
UPPER RIDGE AXIS OVER THE WESTERN CONUS AND AN AMPLIFIED TROUGH
OVER THE EASTERN CONUS. SFC HIGH PRESSURE CONTINUES TO MOVE
OVERHEAD WITH WEAK RETURN FLOW PROGGED TO SET UP EARLY THIS
AFTERNOON. LIGHT WINDS AND INCREASING CLOUD COVER SHOULD LIMIT
HIGHS TO THE UPPER 70S TO AROUND 80 TODAY. YESTERDAY`S VISIBLE
SATELLITE IMAGERY SHOWED AN EXTENSIVE SMOKE PLUME STRETCHING
SOUTHEAST FROM CANADIAN FIRES INTO THE DAKOTAS. IF THICK
ENOUGH...THIS COULD LIMIT TEMPS TODAY AS WELL BUT THAT IS TOUGH TO
DETERMINE AT THIS POINT. THE RECENT RUNS OF THE HRRR AND RAP DO
INDICATE AN AREA OF PCPN DEVELOPING ACROSS THE HIGH PLAINS EARLY
THIS MORNING IN RESPONSE TO A QUICK MOVING IMPULSE DROPPING
THROUGH NORTHWEST FLOW. THIS IMPULSE IS FORECAST TO CONTINUE TO
SLIDE SOUTHEAST ACROSS CENTRAL NEBRASKA AND INTO OUR SOUTHWESTERN
CWA BY THIS AFTERNOON. INSTABILITY LOOKS WEAK THIS AFTERNOON AND
SO THINK SCATTERED SHOWERS WITH A FEW ISOLATED TSTMS COULD DEVELOP
OVER OUR WESTERN CWA AS EARLY AS MID TO LATE AFTERNOON AND
CONTINUE TO STRENGTHEN INTO THE EVENING AND OVERNIGHT HOURS AS
NOSE OF MODEST LLVL JET SHIFTS EASTWARD.
A BIT OF A BREAK IN ACTIVITY IS EXPECTED DURING THE DAY THURSDAY
WHILE STRONG THETA-E ADVECTION BRINGS JULY MOISTURE BACK INTO THE
REGION. ELONGATED SFC LOW PRESSURE WILL EXTEND ACROSS THE HIGH
PLAINS OF WYOMING AND COLORADO WITH STRONG SOUTHERLY FLOW OUT
AHEAD OF IT. BEST CHANCES FOR TSTMS WILL AGAIN BE NOCTURNAL AS THE
NOSE OF STRENGTHENING LLVL JET ADVECTS EAST. THIS COMBINED WITH
STEEPENING MID LEVEL LAPSE RATES SHOULD AID IN ELEVATED TSTMS
ACROSS THE CWA. THE SFC LOW WILL BEGIN TO SLOWLY DRIFT INTO THE
CNTRL PLAINS FRIDAY...PLACING A BOUNDARY ACROSS THE KS/NEB BORDER
BY FRIDAY NIGHT.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 307 AM CDT WED JUL 9 2014
ROUNDS OF NOCTURNAL THUNDERSTORMS ARE LIKELY THROUGH THE WEEKEND AS
A SERIES OF WEAK MID LEVEL IMPULSES DRIFT ACROSS THE CENTRAL PLAINS.
IT IS HARD TO RULE OUT ANY ONE PARTICULAR PERIOD SO HAVE LEFT SMALL
POPS IN FOR MUCH OF THE WEEKEND...ALTHOUGH WE DO NOT ANTICIPATE
CONTINUOUS ACTIVITY. A STRONG COLD FRONT IS PROGGED TO DROP INTO THE
AREA LATE MONDAY/TUESDAY BRINGING BELOW NORMAL TEMPERATURES TO THE
REGION TUESDAY AND WEDNESDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1133 PM CDT TUE JUL 8 2014
VFR CONDITIONS THROUGH THE PERIOD AS HIGH PRESSURE DOMINATES OVER
THE REGION. INCREASING HIGH CLOUDS AFTER 18Z ASSOCIATED WITH MID
LEVEL WARM ADVECTION MOVING INTO THE WESTERN HIGH PLAINS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1028 AM EDT WED JUL 9 2014
.SYNOPSIS...
AFTER THE SEVERE WEATHER OUTBREAK FROM THE MAIN COLD FRONT THAT
PASSED THROUGH LATE TUESDAY...A SECONDARY COLD FRONT WILL MOVE
THROUGH THE AREA THIS AFTERNOON WITH SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS. HIGH PRESSURE WILL THEN DOMINATE THE AREA
WITH QUIET WEATHER THURSDAY AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1020 AM EDT UPDATE...
FORECAST IS IN GOOD SHAPE. DIURNAL THUNDERSTORMS STILL EXPECTED TO
DEVELOP ACROSS THE CWA. EXPECT THESE TO DEVELOP DURING THE
AFTERNOON AND CONTINUE THROUGH THE EVENING. SFC WINDS WILL BE
SOUTHWESTERLY THROUGH THE MORNING HOURS AND BECOME NW AFTER A
SECONDARY COLD FRONT MOVES THROUGH.
STORM SURVEYS ARE STILL IN PROGRESS FROM YESTERDAY`S STORMS. DETAILED
INFORMATION WILL BE PROVIDED WHEN STORMS ARE FULLY INVESTIGATED. THANK
YOU FOR YOUR PATIENCE.
750 AM UPDATE...
THE RESULTS OF THE SIGNIFICANT SEVERE WEATHER OUTBREAK FROM LATE
TUESDAY ARE CONTINUING TO BE REALIZED. THREE NWS STORM SURVEY
TEAMS ARE OUT TODAY TO DETERMINE THE TYPE /TORNADO OR STRAIGHT
LINE/ AND STRENGTH OF WINDS IN THE MOST IMPACTED AREAS...AT THIS
TIME PLANNED FOR ONONDAGA...MADISON...AND ONEIDA COUNTIES IN NEW
YORK...AND BRADFORD TO SUSQUEHANNA COUNTIES IN PENNSYLVANIA. THE
SURVEYING PROCESS MAY GO BEYOND TODAY...AND MAY INCLUDE OTHER
AREAS THAT MAY BECOME APPARENT. WE MOURN THE 4 FATALITIES THAT
OCCURRED IN MADISON COUNTY.
THE SEVERE LINE OF THUNDERSTORMS PRESSED EAST LATE MONDAY EVENING
AS THE PRIMARY COLD FRONT MOVED THROUGH THE REGION. A MUCH DRIER
ATMOSPHERE IS TAKING ITS PLACE...YET STILL SOME MARGINAL INSTABILITY
IS EXPECTED ONCE DIURNAL HEATING GETS GOING TODAY. MODEL CAPE ONLY
ACHIEVE A FEW HUNDRED J/KG AS PER GFS AND RAP MODELS...BUT MORE
LIKE SEVERAL HUNDRED TO NEAR 1000 J/KG IN NAM AND ARW MODELS.
THERE IS STILL A DECENT AMOUNT OF 0-6KM SHEAR...AND WITH LESS
MOISTURE...LOWEST PORTION OF SOUNDING TAKES ON A INVERTED-V LOOK
TO IT WHICH WILL PROMOTE MIXING. HOWEVER...COVERAGE OF SHOWERS AND
THUNDER WILL BE QUITE LIMITED DUE TO MUCH LOWER PRECIPITABLE WATER
VALUES /MAINLY UNDER AN INCH- AND-A-QUARTER/...THE QUESTIONABLE
AMOUNT OF INSTABILITY AS LIFTED INDICES ONLY BARELY GET
NEGATIVE...AND THE MUCH POORER JET SUPPORT COMPARED TO YESTERDAY.
IN FACT...WE ARE NOW GETTING INTO THE LEFT ENTRANCE REGION OF THE
300MB JET INSTEAD OF THE RIGHT...UNFAVORABLE FOR DEVELOPMENT.
STILL...GIVEN SOME OF THE FACTORS ABOVE...I INCLUDED MENTION OF
GUSTY WINDS WITH THE SCATTERED SHOWERS AND THUNDERSTORMS IN THE
FORECAST THIS AFTERNOON...ESPECIALLY CENTRAL TO EASTERN ZONES.
COULD EASILY SEE A FEW GUSTS OF 30-40 MPH OR SO IN THE STRONGEST
CELLS.
WHAT ACTIVITY THAT WE GET TODAY WILL BE HEAVILY DEPENDENT ON
DIURNAL HEATING...AND AS SUCH...IT WILL QUICKLY END LATE
AFTERNOON-EARLY EVENING WITH LOSS OF THAT HEATING AND FURTHER
ENCROACHMENT OF DRY AIR MASS. DEWPOINTS...ALREADY NOTICEABLY LOWER
TODAY COMFORT-WISE...WILL CONTINUE TO CRASH THROUGH THE 50S TONIGHT AND
EVEN ACTUAL TEMPERATURES WILL DO THE SAME IN MOST OF THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
230 AM EDT UPDATE...
UPDATED TEMPS FOR THE PD TO THE LATEST BLENDED MOS GUID. HAVE LEFT
POPS OUT FOR THU DESPITE UPR TROF SWINGING THRU. LOOKS AS THOUGH
SFC HIPRES WILL BE STRONG ENUF TO SQUASH ANY DVLPG CONV ELEMENTS.
TROF MVES EWRD SLOWLY AND WILL BE CNTRD OVER ERN NY AND WRN NEW
ENG FOR FRI WITH SFC HI STILL IN PLACE. PRVS DISC BLO.
140 PM EDT UPDATE...
TONIGHT A COLD FRONT WILL MOVE THROUGH THE AREA AS THE SFC LOW
ATTENDANT WITH THE UPPER LVL TROUGH BRINGING THE POTENTIAL FOR
SEVERE WEATHER TODAY MOVES ALONG THE US/CANADIAN BORDER. COOLER
AND SLIGHTLY DRIER AIR WILL FOLLOW BEHIND THE PASSAGE. THIS MAY BE
ENOUGH TO CAUSE LINGERING SHOWERS OVER THE REGION FROM THE
AFTERNOON/EARLY EVENING ACTIVITY TO DIMINISH. SKIES WILL REMAIN MOSTLY
EARLY WED MORNING THUS TEMPS ARE EXPECTED TO REMAIN IN THE LOW 60S
ACROSS THE REGION.
WED THE UPPR LVL TROUGH AXIS WILL SHIFT SLIGHTLY EAST AND START TO
LIFT NORTH. THE MAIN SUBSIDENCE ATTENDANT WITH THE TROUGH WILL
REMAIN WELL TO THE NORTH OF THE CWA... THUS WE WILL REMAIN UNDER
CYCLONIC FLOW ALOFT THROUGH MUCH OF THE DAY ON WEDNESDAY. THE
COMBINATION FROM UPPR LVL DYNAMICS AND THE BOUNDARY LAYER HAVING
SOME INSTABILITY WED... WILL PRODUCE SHOWERS AND THUNDERSTORMS. THESE
SHOWERS WILL BE DIURNAL DRIVEN AND WHEN THE SUNSETS EXPECT SHOWERS
START TO DIMINISH. REGIONS MAY SEE SOME SUN EARLY ON... HOWEVER
EXPECT A DENSE CU DECK TO BUILD QUICKLY WED AFTERNOON. THIS WILL
KEEP TEMPS COOLER THAN YESTERDAY. WED NIGHT A SECONDARY COLD FRONT WILL
MOVE THROUGH THE REGION ENDING WHAT SHOWERS STILL LINGER.
THURSDAY HIGH PRESSURE WILL START TO BUILD INTO THE NORTHEAST FROM
THE WEST WHICH WILL ALLOW A COUPLE OF BEAUTIFUL DAYS TO RETURN
BACK INTO THE REGION. TEMPERATURES ARE EXPECTED TO REMAIN IN THE
70S AS DEW POINTS WILL BE IN THE 50S. EACH NIGHT TEMPS WILL FALL
INTO THE LOW TO MID 50S. THURS AND FRI WILL BE TRANQUIL WEATHER.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
230 AM EDT UPDATE...LTL CHG TO THE XNTDD AS A BROAD TROF SLOWLY
DVLPS THRU THE PD...GRADUALLY INCRSG THE CHANCE FOR CONV. DAYTIME
HI/S WILL AVG ABV NRML WITH WEAK WAA CONTG INTO TUE. LOWS NEAR
NRML...ESP EARLY. PRVS DISC BLO.
3 PM UPDATE... HIPRES WL BE SHIFTING OFF THE COAST IN THE EARLY
PART OF THE EXTNDD WITH RETURN FLOW BEGINNING TO KICK IN DRG THE
DAY SATURDAY. THIS MAY LEAD TO SLGT CHC THUNDER DRG THE AFTN HRS
AS FRONTAL BNDRY SETS UP TO OUR WEST SUN MRNG. AS FNT APPRCHS DRG
THE DAY ON SUNDAY POPS WL INCRS TO HICHC AND WITH MULTIPLE WVS
POSSIBLY RIDING UP ALONG BNDRY THRU EARLY IN THE WEEK THE CHC FOR
THUNDER CONTS UNTIL FROPA OCCURS BY TUE MRNG. TEMPS WL MODERATE TO
ABV NORMAL FOR THE WEEKEND BFR DROPPING OFF TO NR NORMAL FOLLOWING
FROPA. HV BASICALLY FOLLOWED WPC GUIDANCE WITH JUST A FEW TWEEKS
FOR COLLABORATION WITH SURROUNDING OFFICES.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
UPR TROF DEEPENS OVER THE LAKES AND PUSHES A SCNDRY COLD FNT THRU
THE AREA THIS AFTN. LOOKS LIKE THE BEST CHANCE FOR A BRIEF SHWR
AND MVFR CIG AND VSBY RESTRICTION WILL BE OVER THE ERN AND SRN
TAF SITES AT BGM AND AVP AFT 21Z. OTRW XPCT VFR CONDS THRU THE PD
WITH THE XCPTN OF IFR FOG LATE IN ELM. WEST WINDS TODAY AHD OF THE
SFC FNT WILL GO NW THAN BECOME LGT AFT SUNSET.
OUTLOOK...
THU-FRI-SAT...MAINLY VFR...EXCEPT PREDAWN VALLEY FOG KELM.
SUN...MAINLY VFR...POTENTIAL FOR MVFR IN SHRA AND TSRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...KAH/MDP
SHORT TERM...DGM/KAH
LONG TERM...DGM/PVN
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
751 AM EDT WED JUL 9 2014
.SYNOPSIS...
AFTER THE SEVERE WEATHER OUTBREAK FROM THE MAIN COLD FRONT THAT
PASSED THROUGH LATE TUESDAY...A SECONDARY COLD FRONT WILL MOVE
THROUGH THE AREA THIS AFTERNOON WITH SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS. HIGH PRESSURE WILL THEN DOMINATE THE AREA
WITH QUIET WEATHER THURSDAY AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
750 AM UPDATE...
THE RESULTS OF THE SIGNIFICANT SEVERE WEATHER OUTBREAK FROM LATE
TUESDAY ARE CONTINUING TO BE REALIZED. THREE NWS STORM SURVEY
TEAMS ARE OUT TODAY TO DETERMINE THE TYPE /TORNADO OR STRAIGHT
LINE/ AND STRENGTH OF WINDS IN THE MOST IMPACTED AREAS...AT THIS
TIME PLANNED FOR ONONDAGA...MADISON...AND ONEIDA COUNTIES IN NEW
YORK...AND BRADFORD TO SUSQUEHANNA COUNTIES IN PENNSYLVANIA. THE
SURVEYING PROCESS MAY GO BEYOND TODAY...AND MAY INCLUDE OTHER
AREAS THAT MAY BECOME APPARENT. WE MOURN THE 4 FATALITIES THAT
OCCURRED IN MADISON COUNTY.
THE SEVERE LINE OF THUNDERSTORMS PRESSED EAST LATE MONDAY EVENING
AS THE PRIMARY COLD FRONT MOVED THROUGH THE REGION. A MUCH DRIER
ATMOSPHERE IS TAKING ITS PLACE...YET STILL SOME MARGINAL INSTABILITY
IS EXPECTED ONCE DIURNAL HEATING GETS GOING TODAY. MODEL CAPE ONLY
ACHIEVE A FEW HUNDRED J/KG AS PER GFS AND RAP MODELS...BUT MORE
LIKE SEVERAL HUNDRED TO NEAR 1000 J/KG IN NAM AND ARW MODELS.
THERE IS STILL A DECENT AMOUNT OF 0-6KM SHEAR...AND WITH LESS
MOISTURE...LOWEST PORTION OF SOUNDING TAKES ON A INVERTED-V LOOK
TO IT WHICH WILL PROMOTE MIXING. HOWEVER...COVERAGE OF SHOWERS AND
THUNDER WILL BE QUITE LIMITED DUE TO MUCH LOWER PRECIPITABLE WATER
VALUES /MAINLY UNDER AN INCH- AND-A-QUARTER/...THE QUESTIONABLE
AMOUNT OF INSTABILITY AS LIFTED INDICES ONLY BARELY GET
NEGATIVE...AND THE MUCH POORER JET SUPPORT COMPARED TO YESTERDAY.
IN FACT...WE ARE NOW GETTING INTO THE LEFT ENTRANCE REGION OF THE
300MB JET INSTEAD OF THE RIGHT...UNFAVORABLE FOR DEVELOPMENT.
STILL...GIVEN SOME OF THE FACTORS ABOVE...I INCLUDED MENTION OF
GUSTY WINDS WITH THE SCATTERED SHOWERS AND THUNDERSTORMS IN THE
FORECAST THIS AFTERNOON...ESPECIALLY CENTRAL TO EASTERN ZONES.
COULD EASILY SEE A FEW GUSTS OF 30-40 MPH OR SO IN THE STRONGEST
CELLS.
WHAT ACTIVITY THAT WE GET TODAY WILL BE HEAVILY DEPENDENT ON
DIURNAL HEATING...AND AS SUCH...IT WILL QUICKLY END LATE
AFTERNOON-EARLY EVENING WITH LOSS OF THAT HEATING AND FURTHER
ENCROACHMENT OF DRY AIR MASS. DEWPOINTS...ALREADY NOTICEABLY LOWER
TODAY COMFORT-WISE...WILL CONTINUE TO CRASH THROUGH THE 50S TONIGHT AND
EVEN ACTUAL TEMPERATURES WILL DO THE SAME IN MOST OF THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
230 AM EDT UPDATE...
UPDATED TEMPS FOR THE PD TO THE LATEST BLENDED MOS GUID. HAVE LEFT
POPS OUT FOR THU DESPITE UPR TROF SWINGING THRU. LOOKS AS THOUGH
SFC HIPRES WILL BE STRONG ENUF TO SQUASH ANY DVLPG CONV ELEMENTS.
TROF MVES EWRD SLOWLY AND WILL BE CNTRD OVER ERN NY AND WRN NEW
ENG FOR FRI WITH SFC HI STILL IN PLACE. PRVS DISC BLO.
140 PM EDT UPDATE...
TONIGHT A COLD FRONT WILL MOVE THROUGH THE AREA AS THE SFC LOW
ATTENDANT WITH THE UPPER LVL TROUGH BRINGING THE POTENTIAL FOR
SEVERE WEATHER TODAY MOVES ALONG THE US/CANADIAN BORDER. COOLER
AND SLIGHTLY DRIER AIR WILL FOLLOW BEHIND THE PASSAGE. THIS MAY BE
ENOUGH TO CAUSE LINGERING SHOWERS OVER THE REGION FROM THE
AFTERNOON/EARLY EVENING ACTIVITY TO DIMINISH. SKIES WILL REMAIN MOSTLY
EARLY WED MORNING THUS TEMPS ARE EXPECTED TO REMAIN IN THE LOW 60S
ACROSS THE REGION.
WED THE UPPR LVL TROUGH AXIS WILL SHIFT SLIGHTLY EAST AND START TO
LIFT NORTH. THE MAIN SUBSIDENCE ATTENDANT WITH THE TROUGH WILL
REMAIN WELL TO THE NORTH OF THE CWA... THUS WE WILL REMAIN UNDER
CYCLONIC FLOW ALOFT THROUGH MUCH OF THE DAY ON WEDNESDAY. THE
COMBINATION FROM UPPR LVL DYNAMICS AND THE BOUNDARY LAYER HAVING
SOME INSTABILITY WED... WILL PRODUCE SHOWERS AND THUNDERSTORMS. THESE
SHOWERS WILL BE DIURNAL DRIVEN AND WHEN THE SUNSETS EXPECT SHOWERS
START TO DIMINISH. REGIONS MAY SEE SOME SUN EARLY ON... HOWEVER
EXPECT A DENSE CU DECK TO BUILD QUICKLY WED AFTERNOON. THIS WILL
KEEP TEMPS COOLER THAN YESTERDAY. WED NIGHT A SECONDARY COLD FRONT WILL
MOVE THROUGH THE REGION ENDING WHAT SHOWERS STILL LINGER.
THURSDAY HIGH PRESSURE WILL START TO BUILD INTO THE NORTHEAST FROM
THE WEST WHICH WILL ALLOW A COUPLE OF BEAUTIFUL DAYS TO RETURN
BACK INTO THE REGION. TEMPERATURES ARE EXPECTED TO REMAIN IN THE
70S AS DEW POINTS WILL BE IN THE 50S. EACH NIGHT TEMPS WILL FALL
INTO THE LOW TO MID 50S. THURS AND FRI WILL BE TRANQUIL WEATHER.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
230 AM EDT UPDATE...LTL CHG TO THE XNTDD AS A BROAD TROF SLOWLY
DVLPS THRU THE PD...GRADUALLY INCRSG THE CHANCE FOR CONV. DAYTIME
HI/S WILL AVG ABV NRML WITH WEAK WAA CONTG INTO TUE. LOWS NEAR
NRML...ESP EARLY. PRVS DISC BLO.
3 PM UPDATE... HIPRES WL BE SHIFTING OFF THE COAST IN THE EARLY
PART OF THE EXTNDD WITH RETURN FLOW BEGINNING TO KICK IN DRG THE
DAY SATURDAY. THIS MAY LEAD TO SLGT CHC THUNDER DRG THE AFTN HRS
AS FRONTAL BNDRY SETS UP TO OUR WEST SUN MRNG. AS FNT APPRCHS DRG
THE DAY ON SUNDAY POPS WL INCRS TO HICHC AND WITH MULTIPLE WVS
POSSIBLY RIDING UP ALONG BNDRY THRU EARLY IN THE WEEK THE CHC FOR
THUNDER CONTS UNTIL FROPA OCCURS BY TUE MRNG. TEMPS WL MODERATE TO
ABV NORMAL FOR THE WEEKEND BFR DROPPING OFF TO NR NORMAL FOLLOWING
FROPA. HV BASICALLY FOLLOWED WPC GUIDANCE WITH JUST A FEW TWEEKS
FOR COLLABORATION WITH SURROUNDING OFFICES.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
UPR TROF DEEPENS OVER THE LAKES AND PUSHES A SCNDRY COLD FNT THRU
THE AREA THIS AFTN. LOOKS LIKE THE BEST CHANCE FOR A BRIEF SHWR
AND MVFR CIG AND VSBY RESTRICTION WILL BE OVER THE ERN AND SRN
TAF SITES AT BGM AND AVP AFT 21Z. OTRW XPCT VFR CONDS THRU THE PD
WITH THE XCPTN OF IFR FOG LATE IN ELM. WEST WINDS TODAY AHD OF THE
SFC FNT WILL GO NW THAN BECOME LGT AFT SUNSET.
OUTLOOK...
THU-FRI-SAT...MAINLY VFR...EXCEPT PREDAWN VALLEY FOG KELM.
SUN...MAINLY VFR...POTENTIAL FOR MVFR IN SHRA AND TSRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DGM/KAH
LONG TERM...DGM/PVN
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
639 AM EDT WED JUL 9 2014
.SYNOPSIS...
AFTER THE SEVERE WEATHER OUTBREAK FROM THE MAIN COLD FRONT THAT
PASSED THROUGH LATE TUESDAY...A SECONDARY COLD FRONT WILL MOVE
THROUGH THE AREA TODAY WITH SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. HIGH PRESSURE WILL THEN DOMINATE THE AREA WITH
QUIET WEATHER THURSDAY AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
400 AM UPDATE...
THE RESULTS OF THE SIGNIFICANT SEVERE WEATHER OUTBREAK FROM LATE
TUESDAY ARE CONTINUING TO BE REALIZED. THREE NWS STORM SURVEY
TEAMS WILL BE OUT TODAY TO DETERMINE THE TYPE /TORNADO OR STRAIGHT
LINE/ AND STRENGTH OF WINDS IN THE MOST IMPACTED AREAS...AT THIS
TIME PLANNED FOR ONONDAGA...MADISON...AND ONEIDA COUNTIES IN NEW
YORK...AND BRADFORD TO SUSQUEHANNA COUNTIES IN PENNSYLVANIA. THE
SURVEYING PROCESS MAY GO BEYOND TODAY...AND MAY INCLUDE OTHER
AREAS THAT MAY BECOME APPARENT. WE MOURN THE 4 FATALITIES THAT
OCCURRED IN MADISON COUNTY.
THE SEVERE LINE OF THUNDERSTORMS PRESSED EAST LATE MONDAY EVENING
AS THE PRIMARY COLD FRONT MOVED THROUGH THE REGION. A MUCH DRIER
ATMOSPHERE IS TAKING ITS PLACE...YET STILL SOME MARGINAL INSTABILITY
IS EXPECTED ONCE DIURNAL HEATING GETS GOING TODAY. MODEL CAPE ONLY
ACHIEVE A FEW HUNDRED J/KG AS PER GFS AND RAP MODELS...BUT MORE
LIKE SEVERAL HUNDRED TO NEAR 1000 J/KG IN NAM AND ARW MODELS.
THERE IS STILL A DECENT AMOUNT OF 0-6KM SHEAR...AND WITH LESS
MOISTURE...LOWEST PORTION OF SOUNDING TAKES ON A INVERTED-V LOOK
TO IT WHICH WILL PROMOTE MIXING. HOWEVER...COVERAGE OF SHOWERS AND
THUNDER WILL BE QUITE LIMITED DUE TO MUCH LOWER PRECIPITABLE WATER
VALUES /MAINLY UNDER AN INCH- AND-A-QUARTER/...THE QUESTIONABLE
AMOUNT OF INSTABILITY AS LIFTED INDICES ONLY BARELY GET
NEGATIVE...AND THE MUCH POORER JET SUPPORT COMPARED TO YESTERDAY.
IN FACT...WE ARE NOW GETTING INTO THE LEFT ENTRANCE REGION OF THE
300MB JET INSTEAD OF THE RIGHT...UNFAVORABLE FOR DEVELOPMENT.
STILL...GIVEN SOME OF THE FACTORS ABOVE...I INCLUDED MENTION OF
GUSTY WINDS WITH THE SCATTERED SHOWERS AND THUNDERSTORMS IN THE
FORECAST THIS AFTERNOON...ESPECIALLY CENTRAL TO EASTERN ZONES.
COULD EASILY SEE A FEW GUSTS OF 30-40 MPH OR SO IN THE STRONGEST
CELLS.
WHAT ACTIVITY THAT WE GET TODAY WILL BE HEAVILY DEPENDENT ON
DIURNAL HEATING...AND AS SUCH...IT WILL QUICKLY END LATE
AFTERNOON-EARLY EVENING WITH LOSS OF THAT HEATING AND FURTHER
ENCROACHMENT OF DRY AIR MASS. DEWPOINTS...ALREADY NOTICEABLY LOWER
TODAY COMFORT-WISE...WILL CONTINUE TO CRASH THROUGH THE 50S TONIGHT AND
EVEN ACTUAL TEMPERATURES WILL DO THE SAME IN MOST OF THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
230 AM EDT UPDATE...
UPDATED TEMPS FOR THE PD TO THE LATEST BLENDED MOS GUID. HAVE LEFT
POPS OUT FOR THU DESPITE UPR TROF SWINGING THRU. LOOKS AS THOUGH
SFC HIPRES WILL BE STRONG ENUF TO SQUASH ANY DVLPG CONV ELEMENTS.
TROF MVES EWRD SLOWLY AND WILL BE CNTRD OVER ERN NY AND WRN NEW
ENG FOR FRI WITH SFC HI STILL IN PLACE. PRVS DISC BLO.
140 PM EDT UPDATE...
TONIGHT A COLD FRONT WILL MOVE THROUGH THE AREA AS THE SFC LOW
ATTENDANT WITH THE UPPER LVL TROUGH BRINGING THE POTENTIAL FOR
SEVERE WEATHER TODAY MOVES ALONG THE US/CANADIAN BORDER. COOLER
AND SLIGHTLY DRIER AIR WILL FOLLOW BEHIND THE PASSAGE. THIS MAY BE
ENOUGH TO CAUSE LINGERING SHOWERS OVER THE REGION FROM THE
AFTERNOON/EARLY EVENING ACTIVITY TO DIMINISH. SKIES WILL REMAIN MOSTLY
EARLY WED MORNING THUS TEMPS ARE EXPECTED TO REMAIN IN THE LOW 60S
ACROSS THE REGION.
WED THE UPPR LVL TROUGH AXIS WILL SHIFT SLIGHTLY EAST AND START TO
LIFT NORTH. THE MAIN SUBSIDENCE ATTENDANT WITH THE TROUGH WILL
REMAIN WELL TO THE NORTH OF THE CWA... THUS WE WILL REMAIN UNDER
CYCLONIC FLOW ALOFT THROUGH MUCH OF THE DAY ON WEDNESDAY. THE
COMBINATION FROM UPPR LVL DYNAMICS AND THE BOUNDARY LAYER HAVING
SOME INSTABILITY WED... WILL PRODUCE SHOWERS AND THUNDERSTORMS. THESE
SHOWERS WILL BE DIURNAL DRIVEN AND WHEN THE SUNSETS EXPECT SHOWERS
START TO DIMINISH. REGIONS MAY SEE SOME SUN EARLY ON... HOWEVER
EXPECT A DENSE CU DECK TO BUILD QUICKLY WED AFTERNOON. THIS WILL
KEEP TEMPS COOLER THAN YESTERDAY. WED NIGHT A SECONDARY COLD FRONT WILL
MOVE THROUGH THE REGION ENDING WHAT SHOWERS STILL LINGER.
THURSDAY HIGH PRESSURE WILL START TO BUILD INTO THE NORTHEAST FROM
THE WEST WHICH WILL ALLOW A COUPLE OF BEAUTIFUL DAYS TO RETURN
BACK INTO THE REGION. TEMPERATURES ARE EXPECTED TO REMAIN IN THE
70S AS DEW POINTS WILL BE IN THE 50S. EACH NIGHT TEMPS WILL FALL
INTO THE LOW TO MID 50S. THURS AND FRI WILL BE TRANQUIL WEATHER.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
230 AM EDT UPDATE...LTL CHG TO THE XNTDD AS A BROAD TROF SLOWLY
DVLPS THRU THE PD...GRADUALLY INCRSG THE CHANCE FOR CONV. DAYTIME
HI/S WILL AVG ABV NRML WITH WEAK WAA CONTG INTO TUE. LOWS NEAR
NRML...ESP EARLY. PRVS DISC BLO.
3 PM UPDATE... HIPRES WL BE SHIFTING OFF THE COAST IN THE EARLY
PART OF THE EXTNDD WITH RETURN FLOW BEGINNING TO KICK IN DRG THE
DAY SATURDAY. THIS MAY LEAD TO SLGT CHC THUNDER DRG THE AFTN HRS
AS FRONTAL BNDRY SETS UP TO OUR WEST SUN MRNG. AS FNT APPRCHS DRG
THE DAY ON SUNDAY POPS WL INCRS TO HICHC AND WITH MULTIPLE WVS
POSSIBLY RIDING UP ALONG BNDRY THRU EARLY IN THE WEEK THE CHC FOR
THUNDER CONTS UNTIL FROPA OCCURS BY TUE MRNG. TEMPS WL MODERATE TO
ABV NORMAL FOR THE WEEKEND BFR DROPPING OFF TO NR NORMAL FOLLOWING
FROPA. HV BASICALLY FOLLOWED WPC GUIDANCE WITH JUST A FEW TWEEKS
FOR COLLABORATION WITH SURROUNDING OFFICES.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
UPR TROF DEEPENS OVER THE LAKES AND PUSHES A SCNDRY COLD FNT THRU
THE AREA THIS AFTN. LOOKS LIKE THE BEST CHANCE FOR A BRIEF SHWR
AND MVFR CIG AND VSBY RESTRICTION WILL BE OVER THE ERN AND SRN
TAF SITES AT BGM AND AVP AFT 21Z. OTRW XPCT VFR CONDS THRU THE PD
WITH THE XCPTN OF IFR FOG LATE IN ELM. WEST WINDS TODAY AHD OF THE
SFC FNT WILL GO NW THAN BECOME LGT AFT SUNSET.
OUTLOOK...
THU-FRI-SAT...MAINLY VFR...EXCEPT PREDAWN VALLEY FOG KELM.
SUN...MAINLY VFR...POTENTIAL FOR MVFR IN SHRA AND TSRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DGM/KAH
LONG TERM...DGM/PVN
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
403 AM EDT WED JUL 9 2014
.SYNOPSIS...
AFTER THE SEVERE WEATHER OUTBREAK FROM THE MAIN COLD FRONT THAT
PASSED THROUGH LATE TUESDAY...A SECONDARY COLD FRONT WILL MOVE
THROUGH THE AREA TODAY WITH SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. HIGH PRESSURE WILL THEN DOMINATE THE AREA WITH
QUIET WEATHER THURSDAY AND FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
400 AM UPDATE...
THE RESULTS OF THE SIGNIFICANT SEVERE WEATHER OUTBREAK FROM LATE
TUESDAY ARE CONTINUING TO BE REALIZED. THREE NWS STORM SURVEY
TEAMS WILL BE OUT TODAY TO DETERMINE THE TYPE /TORNADO OR STRAIGHT
LINE/ AND STRENGTH OF WINDS IN THE MOST IMPACTED AREAS...AT THIS
TIME PLANNED FOR ONONDAGA...MADISON...AND ONEIDA COUNTIES IN NEW
YORK...AND BRADFORD TO SUSQUEHANNA COUNTIES IN PENNSYLVANIA. THE
SURVEYING PROCESS MAY GO BEYOND TODAY...AND MAY INCLUDE OTHER
AREAS THAT MAY BECOME APPARENT. WE MOURN THE 4 FATALITIES THAT
OCCURRED IN MADISON COUNTY.
THE SEVERE LINE OF THUNDERSTORMS PRESSED EAST LATE MONDAY EVENING
AS THE PRIMARY COLD FRONT MOVED THROUGH THE REGION. A MUCH DRIER
ATMOSPHERE IS TAKING ITS PLACE...YET STILL SOME MARGINAL INSTABILITY
IS EXPECTED ONCE DIURNAL HEATING GETS GOING TODAY. MODEL CAPE ONLY
ACHIEVE A FEW HUNDRED J/KG AS PER GFS AND RAP MODELS...BUT MORE
LIKE SEVERAL HUNDRED TO NEAR 1000 J/KG IN NAM AND ARW MODELS.
THERE IS STILL A DECENT AMOUNT OF 0-6KM SHEAR...AND WITH LESS
MOISTURE...LOWEST PORTION OF SOUNDING TAKES ON A INVERTED-V LOOK
TO IT WHICH WILL PROMOTE MIXING. HOWEVER...COVERAGE OF SHOWERS AND
THUNDER WILL BE QUITE LIMITED DUE TO MUCH LOWER PRECIPITABLE WATER
VALUES /MAINLY UNDER AN INCH- AND-A-QUARTER/...THE QUESTIONABLE
AMOUNT OF INSTABILITY AS LIFTED INDICES ONLY BARELY GET
NEGATIVE...AND THE MUCH POORER JET SUPPORT COMPARED TO YESTERDAY.
IN FACT...WE ARE NOW GETTING INTO THE LEFT ENTRANCE REGION OF THE
300MB JET INSTEAD OF THE RIGHT...UNFAVORABLE FOR DEVELOPMENT.
STILL...GIVEN SOME OF THE FACTORS ABOVE...I INCLUDED MENTION OF
GUSTY WINDS WITH THE SCATTERED SHOWERS AND THUNDERSTORMS IN THE
FORECAST THIS AFTERNOON...ESPECIALLY CENTRAL TO EASTERN ZONES.
COULD EASILY SEE A FEW GUSTS OF 30-40 MPH OR SO IN THE STRONGEST
CELLS.
WHAT ACTIVITY THAT WE GET TODAY WILL BE HEAVILY DEPENDENT ON
DIURNAL HEATING...AND AS SUCH...IT WILL QUICKLY END LATE
AFTERNOON-EARLY EVENING WITH LOSS OF THAT HEATING AND FURTHER
ENCROACHMENT OF DRY AIR MASS. DEWPOINTS...ALREADY NOTICEABLY LOWER
TODAY COMFORT-WISE...WILL CONTINUE TO CRASH THROUGH THE 50S TONIGHT AND
EVEN ACTUAL TEMPERATURES WILL DO THE SAME IN MOST OF THE AREA.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
230 AM EDT UPDATE...
UPDATED TEMPS FOR THE PD TO THE LATEST BLENDED MOS GUID. HAVE LEFT
POPS OUT FOR THU DESPITE UPR TROF SWINGING THRU. LOOKS AS THOUGH
SFC HIPRES WILL BE STRONG ENUF TO SQUASH ANY DVLPG CONV ELEMENTS.
TROF MVES EWRD SLOWLY AND WILL BE CNTRD OVER ERN NY AND WRN NEW
ENG FOR FRI WITH SFC HI STILL IN PLACE. PRVS DISC BLO.
140 PM EDT UPDATE...
TONIGHT A COLD FRONT WILL MOVE THROUGH THE AREA AS THE SFC LOW
ATTENDANT WITH THE UPPER LVL TROUGH BRINGING THE POTENTIAL FOR
SEVERE WEATHER TODAY MOVES ALONG THE US/CANADIAN BORDER. COOLER
AND SLIGHTLY DRIER AIR WILL FOLLOW BEHIND THE PASSAGE. THIS MAY BE
ENOUGH TO CAUSE LINGERING SHOWERS OVER THE REGION FROM THE
AFTERNOON/EARLY EVENING ACTIVITY TO DIMINISH. SKIES WILL REMAIN MOSTLY
EARLY WED MORNING THUS TEMPS ARE EXPECTED TO REMAIN IN THE LOW 60S
ACROSS THE REGION.
WED THE UPPR LVL TROUGH AXIS WILL SHIFT SLIGHTLY EAST AND START TO
LIFT NORTH. THE MAIN SUBSIDENCE ATTENDANT WITH THE TROUGH WILL
REMAIN WELL TO THE NORTH OF THE CWA... THUS WE WILL REMAIN UNDER
CYCLONIC FLOW ALOFT THROUGH MUCH OF THE DAY ON WEDNESDAY. THE
COMBINATION FROM UPPR LVL DYNAMICS AND THE BOUNDARY LAYER HAVING
SOME INSTABILITY WED... WILL PRODUCE SHOWERS AND THUNDERSTORMS. THESE
SHOWERS WILL BE DIURNAL DRIVEN AND WHEN THE SUNSETS EXPECT SHOWERS
START TO DIMINISH. REGIONS MAY SEE SOME SUN EARLY ON... HOWEVER
EXPECT A DENSE CU DECK TO BUILD QUICKLY WED AFTERNOON. THIS WILL
KEEP TEMPS COOLER THAN YESTERDAY. WED NIGHT A SECONDARY COLD FRONT WILL
MOVE THROUGH THE REGION ENDING WHAT SHOWERS STILL LINGER.
THURSDAY HIGH PRESSURE WILL START TO BUILD INTO THE NORTHEAST FROM
THE WEST WHICH WILL ALLOW A COUPLE OF BEAUTIFUL DAYS TO RETURN
BACK INTO THE REGION. TEMPERATURES ARE EXPECTED TO REMAIN IN THE
70S AS DEW POINTS WILL BE IN THE 50S. EACH NIGHT TEMPS WILL FALL
INTO THE LOW TO MID 50S. THURS AND FRI WILL BE TRANQUIL WEATHER.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
230 AM EDT UPDATE...LTL CHG TO THE XNTDD AS A BROAD TROF SLOWLY
DVLPS THRU THE PD...GRADUALLY INCRSG THE CHANCE FOR CONV. DAYTIME
HI/S WILL AVG ABV NRML WITH WEAK WAA CONTG INTO TUE. LOWS NEAR
NRML...ESP EARLY. PRVS DISC BLO.
3 PM UPDATE... HIPRES WL BE SHIFTING OFF THE COAST IN THE EARLY
PART OF THE EXTNDD WITH RETURN FLOW BEGINNING TO KICK IN DRG THE
DAY SATURDAY. THIS MAY LEAD TO SLGT CHC THUNDER DRG THE AFTN HRS
AS FRONTAL BNDRY SETS UP TO OUR WEST SUN MRNG. AS FNT APPRCHS DRG
THE DAY ON SUNDAY POPS WL INCRS TO HICHC AND WITH MULTIPLE WVS
POSSIBLY RIDING UP ALONG BNDRY THRU EARLY IN THE WEEK THE CHC FOR
THUNDER CONTS UNTIL FROPA OCCURS BY TUE MRNG. TEMPS WL MODERATE TO
ABV NORMAL FOR THE WEEKEND BFR DROPPING OFF TO NR NORMAL FOLLOWING
FROPA. HV BASICALLY FOLLOWED WPC GUIDANCE WITH JUST A FEW TWEEKS
FOR COLLABORATION WITH SURROUNDING OFFICES.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
COLD FNT HAS PASSED THRU THE REGION AND IS NOW FLWD BY CAA AND
DRIER AIR. SOME LGT FOG PSBLE BUT VFR SHD PREVAIL OVRNGT. AFT
SUNRISE...XPCT VFR CONDS TO CONT BUT WITH AN UPR WV AND SCNDRY FNT
PASSING THRU...SOME CONV PSBL IN THE LATE AFTN. ATTM IT LOOKS LIKE
THE BEST CHANCE WILL BE EAST OF THE TAF SITES SO WILL NOT INCLUDE
IN THE FCST FOR NOW...BUT WILL REEVALUATE FOR THE NEXT ISSUANCE.
VFR CONTS THRU THE END OF THE PD.
OUTLOOK...
THU-FRI-SAT...MAINLY VFR...EXCEPT PREDAWN VALLEY FOG KELM.
SUN...MAINLY VFR...POTENTIAL FOR MVFR IN SHRA AND TSRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...DGM/KAH
LONG TERM...DGM/PVN
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1000 PM EDT THU JUL 10 2014
.SYNOPSIS...A WEAKENING COLD FRONT WILL SHIFT THROUGH THE REGION
THROUGH TONIGHT... THEN MOVE TOWARD THE COAST FRIDAY. WEAK HIGH
PRESSURE WILL SETTLE OVER THE REGION SATURDAY INTO SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 1000 PM THURSDAY...
AFTERNOON AND EARLY EVENING CONVECTION HAS STABILIZED MOST AREAS EAST
OF US HWY 1...WHILE SPC MESOANALYSIS AND RAP SOUNDINGS SHOW AROUND
500 J/KG MLCAPE AND LESS THAN ONLY 100 J/KG MLCINH OVER THE WESTERN
PIEDMONT. THE UPPER TROUGH AND ASSOCIATED VORTICITY MAX ARE STILL
TO THE WEST...APPROACHING THE APPALACHIANS THIS EVENING. THE
PRIMARY COLD FRONT IS ALSO JUST WEST OF OR BEGINNING TO CROSS THE
MOUNTAINS...WITH A SHARP TROUGH IN THE LESS OF THE MOUNTAINS.
BLENDED TPW SHOW PW STILL WELL ABOVE 1.5 INCHES. RADAR TRENDS HAVE
BEEN DOWNWARD TO JUST A COUPLE ISOLATED SHOWERS OVER DAVIDSON AND
RANDOLPH/CHATHAM COUNTIES....AND THE HRRR SHOWS VERY LITTLE QPF
AFTER MIDNIGHT. THERE MAY STILL BE A FEW SHOWERS OR AN ISOLATED
STORM GIVEN THE AFOREMENTIONED FORCING...ESPECIALLY WITH THE UPPER
VORT MAX AND PRIMARY COLD FRONT. WILL LOWER POPS A BIT
AREAWIDE...WHILE KEEPING A SLIGHT CHANCE WEST AND CHANCE EAST. ALSO
ADDING PATCHY FOG GIVEN THE WIDESPREAD RAIN AND PARTIAL CLEARING
AHEAD OF THE FRONT. -BLS
FOR FRI/FRI NIGHT: AS THE DAMPENING SHEAR AXIS SHIFTS TO OUR SE IN
LINE WITH THE DISSIPATING SURFACE TROUGH... THE HIGHER PW VALUES
WILL ACCORDINGLY SHIFT TO THE COASTAL PLAIN... LEAVING A LIGHT NNE
LOW LEVEL FLOW AND RELATIVELY (FOR JULY) DRY COLUMN OVER THE NRN AND
WRN CWA. MODELS GENERALLY INDICATE VERY LITTLE PRECIP COVERAGE...
CONFINING AFTERNOON CONVECTION TO THE COASTAL PLAIN AND SE SANDHILLS
WHERE MODELS PROJECT MUCAPE PEAKING AT 1000-1500 J/KG. WILL RETAIN
CHANCE POPS HERE WITH ISOLATED CHANCES TO THE NW. A DIP IN
THICKNESSES TO SLIGHTLY BELOW NORMAL VALUES SUPPORTS HIGHS OF 85-90.
EXPECT LITTLE MORE THAN PATCHY SHOWERS FRI NIGHT. LOWS 66-71. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 315 PM THURSDAY...
THE MID LEVEL TROUGH AXIS (CURRENTLY MOVING TOWARDS THE AREA) WILL
PUSH OFFSHORE ON SATURDAY...WHILE THE MID LEVEL RIDGE TRIES TO BUILD
EASTWARD TOWARDS THE REGION. MODELS HAVE TRENDED DRIER FOR THE
WEEKEND...ESPECIALLY ON SATURDAY GIVEN THE DRIER AIR FILTERING INTO
THE REGION BEHIND THE DEPARTING TROUGH. IN FACT...FORECAST SOUNDINGS
INDICATE VERY LIMITED DEEP LAYER MOISTURE...WITH PWAT VALUES PROGGED
TO RANGE BETWEEN 1-1.25 INCHES (WELL BELOW NORMAL). THEREFORE...
WILL GO WITH A MOSTLY DRY FORECAST FOR SATURDAY. MOISTURE WILL START
TO RECOVER SOME ON SUNDAY AND A SURFACE TROUGH WILL SHARPEN UP OVER
THE REGION...LEADING TO A BETTER CHANCE OF MOSTLY DIURNAL TYPE
STORMS...ALTHOUGH OVERALL COVERAGE SHOULD STILL BE RATHER LOW. LOW
LEVEL THICKNESS VALUES ARE PROGGED TO BE NEAR 1420M ON SATURDAY AND
GIVEN EXPECTED LACK OF PRECIP...TEMPS SHOULD RISE INTO THE UPPER 80S
TO LOWER 90S. BY SUNDAY...LOW LEVEL THICKNESS VALUES ARE EXPECTED TO
CLIMB ANOTHER 5-10M...RESULTING HIGH TEMPS A FEW DEGREES
WARMER...GENERALLY LOW TO MID 90S (ALTHOUGH MORE CLOUDS MAY BE
AROUND WHICH WOULD TEMPER THE WARMING SOME).
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 315 PM THURSDAY...
A DEEP VORTEX IS PROGGED TO MOVE SOUTH OUT OF CANADA AND EVENTUALLY
ACROSS THE GREAT LAKES THROUGH THE MIDDLE OF NEXT WEEK. THIS WILL
RESULT IN A DEEP TROUGH DEVELOPING OVER THE EASTERN HALF OF THE
CONUS. THEREFORE...PRECIP CHANCES WILL BE ON THE INCREASE FOR NEXT
WEEK...ESPECIALLY LATE TUESDAY INTO EARLY WEDNESDAY AS A FRONT
APPROACHES THE AREA. ALSO...GIVEN THIS UNSEASONABLY STRONG TROUGH...
THE MID LEVEL FLOW IS EXPECTED TO STRENGTHEN AND THEREFORE THE
POSSIBILITY OF AN ORGANIZED SEVERE THREAT WILL EXIST AND THIS WILL BE
MONITORED OVER THE NEXT SEVERAL DAYS. THEN THERE IS STILL A GOOD BIT
OF UNCERTAINTY WITH REGARDS TO IF THIS FRONT WILL PUSH ALL THE WAY
THROUGH THE AREA...BUT FOR NOW IT LOOKS LIKE THE FRONT WILL STALL
SOMEWHERE ACROSS THE CAROLINAS. THUS...WILL SHOW A LITTLE DECREASE
IN POPS FOR THE LATTER HALF OF THE WEEK...BUT WILL KEEP A CHANCE IN
GIVEN THE UNCERTAINTY WITH REGARDS TO WHERE THE FRONT ENDS UP. HIGH
TEMPS AHEAD OF THE FRONT ARE EXPECTED TO BE IN THE LOW TO MID 90S ON
MONDAY AND POSSIBLY TUESDAY...ALTHOUGH DEPENDING ON THE TIMING OF
THE PRECIP...TEMPS COULD BE SLIGHTLY LOWER ON TUESDAY. THEN SLIGHTLY
COOLER TEMPS ARE EXPECTED WEDNESDAY AND THURSDAY GIVEN THE DEEP
TROUGHING OVER THE EAST COAST AND THE POSSIBILITY THAT THE FRONT
WILL PUSH THROUGH THE AREA.
&&
AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 806 PM THURSDAY...
SHOWERS AND THUNDERSTORMS CONTINUE TO AFFECT KRDU... KFAY... AND
KRWI... AND ARE LESS LIKELY AT KINT AND KGSO. WINDS WILL BECOME
NORTHERLY TO NORTHEASTERLY OVERNIGHT AS THE FRONT TO THE WEST OF THE
AREA SLOWLY MOVES THROUGH. THERE ARE INDICATIONS OF A PERIOD OF
STRATUS OR FOG NEAR SUNRISE BETWEEN 09 AND 12Z... AND FOG SEEMS MORE
LIKELY AT KRDU... KFAY... AND KRWI... WHERE THE MOST RAIN HAS FALLEN.
LOOKING BEYOND 18Z FRI... VFR CONDITIONS WILL AGAIN DOMINATE BUT A
FEW STORMS WITH GUSTY WINDS AND SUB-VFR CONDITIONS ARE EXPECTED AT
RDU AND PARTICULARLY RWI/FAY FRI AFTERNOON/EVENING. ARRIVAL OF A
DRIER AND MORE STABLE AIR MASS FRI NIGHT THROUGH SUN WILL LEAD TO A
HIGH CONFIDENCE IN VFR CONDITIONS OVER THE WEEKEND. A RETURN TO
SCATTERED LATE DAY SHOWERS AND STORMS IS EXPECTED MON-TUE... WITH A
CHANCE OF LIGHT SUB-VFR FOG WITHIN A FEW HOURS OF DAWN BOTH MON AND
TUE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS/HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...KRD
LONG TERM...KRD
AVIATION...SEC/HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
809 PM EDT THU JUL 10 2014
.SYNOPSIS...A WEAKENING COLD FRONT WILL SHIFT THROUGH THE REGION
THROUGH TONIGHT... THEN MOVE TOWARD THE COAST FRIDAY. WEAK HIGH
PRESSURE WILL SETTLE OVER THE REGION SATURDAY INTO SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 710 PM THURSDAY...
EARLY UPDATE... THE SEVERE THUNDERSTORM WATCH FOR THE EASTERN CWA
HAS BEEN CANCELLED. MUCH OF THE WATCH AREA HAS BEEN OVERTURNED BY
CONVECTION....SO THE THREAT OF WIDESPREAD SEVERE STORMS HAS
DIMINISHED. THERE IS STILL SUPPORT FOR ADDITIONAL STORMS WITH THE
UPPER TROUGH TO THE WEST...ESPECIALLY FOR AREAS WEST OF US HWY 1
WHICH REMAIN SLIGHTLY UNSTABLE. -BLS
PREVIOUS DISCUSSION...
THROUGH TONIGHT: FOCUS REMAINS ON THE EASTERN
HALF OF CENTRAL NC... MAINLY ALONG/EAST OF HIGHWAY 1... FOR NUMEROUS
SHOWERS AND STORMS THROUGH THIS EVENING. STORMS THUS FAR HAVE BEEN
PRIMARILY MULTICELL CLUSTERS WITH A COUPLE OF PROMINENT
SUPERCELLS... AND THIS MODE OF CONVECTION IS LIKELY TO PERSIST FOR
SEVERAL MORE HOURS. CONFLUENT SSW FLOW ALOFT AHEAD OF A MID LEVEL
SHEAR AXIS SITTING JUST TO OUR WEST WILL CONTINUE TO DRAW POCKETS OF
SRN STREAM VORTICITY ACROSS NC... ALONG AND AHEAD OF A WEAK SURFACE
TROUGH. THIS FORCING FOR ASCENT COMBINED WITH WEAK HEIGHT FALLS AND
NRN-STREAM ENERGY... ENHANCED LIFT WITHIN THE RIGHT ENTRANCE REGION
OF THE 100+ KT UPPER JET CORE CENTERED OVER THE NORTHEAST STATES...
AND ABOVE NORMAL PW (1.8-2.0 IN.) WILL ALL SUPPORT A CONTINUED
THREAT OF NUMEROUS SHOWERS AND STORMS IN THE EAST... WITH LESSER
COVERAGE IN THE WEST WITHIN LOWER PW AND SLIGHTLY MORE STABLE AIR
DUE TO THIS MORNING`S SHOWERS/CLOUDS. THIS SCENARIO IS SUPPORTED BY
THE LATEST HRRR GUIDANCE AS WELL AS THE WRF-ARW/NMM. CONCERN
PERSISTS FOR A FEW SEVERE STORMS INTO EARLY EVENING IN THE EASTERN
CWA (PARTICULARLY SOUTHEAST SECTIONS SE OF RALEIGH) WHERE MODERATE
INSTABILITY IS ALIGNED WITH DECENT DEEP LAYER EFFECTIVE SHEAR OF 25-
30 KTS... 500 MB WINDS OF 30-40 KTS... AND D-CAPE OF 800-1200 J/KG.
AS THE WEAKENING MID LEVEL SHEAR AXIS SHIFTS SLOWLY EASTWARD AND
OVERHEAD OVERNIGHT... STORM COVERAGE SHOULD SLOWLY SHRINK AS WE LOSE
HEATING... ENDING LAST OVER THE ERN COASTAL PLAIN... AS THE SURFACE
BOUNDARY SETTLES OVER SE NC. PLENTIFUL LOW LEVEL MOISTURE AND WEAK
MASS CONVERGENCE SHOULD RESULT IN POCKETS OF FOG/STRATUS AREAWIDE
OVERNIGHT. HIGH-RES GUIDANCE AND PERSISTENCE SUGGEST LOWS TONIGHT OF
67-73.
FOR FRI/FRI NIGHT: AS THE DAMPENING SHEAR AXIS SHIFTS TO OUR SE IN
LINE WITH THE DISSIPATING SURFACE TROUGH... THE HIGHER PW VALUES
WILL ACCORDINGLY SHIFT TO THE COASTAL PLAIN... LEAVING A LIGHT NNE
LOW LEVEL FLOW AND RELATIVELY (FOR JULY) DRY COLUMN OVER THE NRN AND
WRN CWA. MODELS GENERALLY INDICATE VERY LITTLE PRECIP COVERAGE...
CONFINING AFTERNOON CONVECTION TO THE COASTAL PLAIN AND SE SANDHILLS
WHERE MODELS PROJECT MUCAPE PEAKING AT 1000-1500 J/KG. WILL RETAIN
CHANCE POPS HERE WITH ISOLATED CHANCES TO THE NW. A DIP IN
THICKNESSES TO SLIGHTLY BELOW NORMAL VALUES SUPPORTS HIGHS OF 85-90.
EXPECT LITTLE MORE THAN PATCHY SHOWERS FRI NIGHT. LOWS 66-71. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 315 PM THURSDAY...
THE MID LEVEL TROUGH AXIS (CURRENTLY MOVING TOWARDS THE AREA) WILL
PUSH OFFSHORE ON SATURDAY...WHILE THE MID LEVEL RIDGE TRIES TO BUILD
EASTWARD TOWARDS THE REGION. MODELS HAVE TRENDED DRIER FOR THE
WEEKEND...ESPECIALLY ON SATURDAY GIVEN THE DRIER AIR FILTERING INTO
THE REGION BEHIND THE DEPARTING TROUGH. IN FACT...FORECAST SOUNDINGS
INDICATE VERY LIMITED DEEP LAYER MOISTURE...WITH PWAT VALUES PROGGED
TO RANGE BETWEEN 1-1.25 INCHES (WELL BELOW NORMAL). THEREFORE...
WILL GO WITH A MOSTLY DRY FORECAST FOR SATURDAY. MOISTURE WILL START
TO RECOVER SOME ON SUNDAY AND A SURFACE TROUGH WILL SHARPEN UP OVER
THE REGION...LEADING TO A BETTER CHANCE OF MOSTLY DIURNAL TYPE
STORMS...ALTHOUGH OVERALL COVERAGE SHOULD STILL BE RATHER LOW. LOW
LEVEL THICKNESS VALUES ARE PROGGED TO BE NEAR 1420M ON SATURDAY AND
GIVEN EXPECTED LACK OF PRECIP...TEMPS SHOULD RISE INTO THE UPPER 80S
TO LOWER 90S. BY SUNDAY...LOW LEVEL THICKNESS VALUES ARE EXPECTED TO
CLIMB ANOTHER 5-10M...RESULTING HIGH TEMPS A FEW DEGREES
WARMER...GENERALLY LOW TO MID 90S (ALTHOUGH MORE CLOUDS MAY BE
AROUND WHICH WOULD TEMPER THE WARMING SOME).
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 315 PM THURSDAY...
A DEEP VORTEX IS PROGGED TO MOVE SOUTH OUT OF CANADA AND EVENTUALLY
ACROSS THE GREAT LAKES THROUGH THE MIDDLE OF NEXT WEEK. THIS WILL
RESULT IN A DEEP TROUGH DEVELOPING OVER THE EASTERN HALF OF THE
CONUS. THEREFORE...PRECIP CHANCES WILL BE ON THE INCREASE FOR NEXT
WEEK...ESPECIALLY LATE TUESDAY INTO EARLY WEDNESDAY AS A FRONT
APPROACHES THE AREA. ALSO...GIVEN THIS UNSEASONABLY STRONG TROUGH...
THE MID LEVEL FLOW IS EXPECTED TO STRENGTHEN AND THEREFORE THE
POSSIBILITY OF AN ORGANIZED SEVERE THREAT WILL EXIST AND THIS WILL BE
MONITORED OVER THE NEXT SEVERAL DAYS. THEN THERE IS STILL A GOOD BIT
OF UNCERTAINTY WITH REGARDS TO IF THIS FRONT WILL PUSH ALL THE WAY
THROUGH THE AREA...BUT FOR NOW IT LOOKS LIKE THE FRONT WILL STALL
SOMEWHERE ACROSS THE CAROLINAS. THUS...WILL SHOW A LITTLE DECREASE
IN POPS FOR THE LATTER HALF OF THE WEEK...BUT WILL KEEP A CHANCE IN
GIVEN THE UNCERTAINTY WITH REGARDS TO WHERE THE FRONT ENDS UP. HIGH
TEMPS AHEAD OF THE FRONT ARE EXPECTED TO BE IN THE LOW TO MID 90S ON
MONDAY AND POSSIBLY TUESDAY...ALTHOUGH DEPENDING ON THE TIMING OF
THE PRECIP...TEMPS COULD BE SLIGHTLY LOWER ON TUESDAY. THEN SLIGHTLY
COOLER TEMPS ARE EXPECTED WEDNESDAY AND THURSDAY GIVEN THE DEEP
TROUGHING OVER THE EAST COAST AND THE POSSIBILITY THAT THE FRONT
WILL PUSH THROUGH THE AREA.
&&
AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 806 PM THURSDAY...
SHOWERS AND THUNDERSTORMS CONTINUE TO AFFECT KRDU... KFAY... AND
KRWI... AND ARE LESS LIKELY AT KINT AND KGSO. WINDS WILL BECOME
NORTHERLY TO NORTHEASTERLY OVERNIGHT AS THE FRONT TO THE WEST OF THE
AREA SLOWLY MOVES THROUGH. THERE ARE INDICATIONS OF A PERIOD OF
STRATUS OR FOG NEAR SUNRISE BETWEEN 09 AND 12Z... AND FOG SEEMS MORE
LIKELY AT KRDU... KFAY... AND KRWI... WHERE THE MOST RAIN HAS FALLEN.
LOOKING BEYOND 18Z FRI... VFR CONDITIONS WILL AGAIN DOMINATE BUT A
FEW STORMS WITH GUSTY WINDS AND SUB-VFR CONDITIONS ARE EXPECTED AT
RDU AND PARTICULARLY RWI/FAY FRI AFTERNOON/EVENING. ARRIVAL OF A
DRIER AND MORE STABLE AIR MASS FRI NIGHT THROUGH SUN WILL LEAD TO A
HIGH CONFIDENCE IN VFR CONDITIONS OVER THE WEEKEND. A RETURN TO
SCATTERED LATE DAY SHOWERS AND STORMS IS EXPECTED MON-TUE... WITH A
CHANCE OF LIGHT SUB-VFR FOG WITHIN A FEW HOURS OF DAWN BOTH MON AND
TUE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS/HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...KRD
LONG TERM...KRD
AVIATION...SEC/HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
710 PM EDT THU JUL 10 2014
.SYNOPSIS...A WEAKENING COLD FRONT WILL SHIFT THROUGH THE REGION
THROUGH TONIGHT... THEN MOVE TOWARD THE COAST FRIDAY. WEAK HIGH
PRESSURE WILL SETTLE OVER THE REGION SATURDAY INTO SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 710 PM THURSDAY...
EARLY UPDATE... THE SEVERE THUNDERSTORM WATCH FOR THE EASTERN CWA
HAS BEEN CANCELLED. MUCH OF THE WATCH AREA HAS BEEN OVERTURNED BY
CONVECTION....SO THE THREAT OF WIDESPREAD SEVERE STORMS HAS
DIMINISHED. THERE IS STILL SUPPORT FOR ADDITIONAL STORMS WITH THE
UPPER TROUGH TO THE WEST...ESPECIALLY FOR AREAS WEST OF US HWY 1
WHICH REMAIN SLIGHTLY UNSTABLE. -BLS
PREVIOUS DISCUSSION...
THROUGH TONIGHT: FOCUS REMAINS ON THE EASTERN
HALF OF CENTRAL NC... MAINLY ALONG/EAST OF HIGHWAY 1... FOR NUMEROUS
SHOWERS AND STORMS THROUGH THIS EVENING. STORMS THUS FAR HAVE BEEN
PRIMARILY MULTICELL CLUSTERS WITH A COUPLE OF PROMINENT
SUPERCELLS... AND THIS MODE OF CONVECTION IS LIKELY TO PERSIST FOR
SEVERAL MORE HOURS. CONFLUENT SSW FLOW ALOFT AHEAD OF A MID LEVEL
SHEAR AXIS SITTING JUST TO OUR WEST WILL CONTINUE TO DRAW POCKETS OF
SRN STREAM VORTICITY ACROSS NC... ALONG AND AHEAD OF A WEAK SURFACE
TROUGH. THIS FORCING FOR ASCENT COMBINED WITH WEAK HEIGHT FALLS AND
NRN-STREAM ENERGY... ENHANCED LIFT WITHIN THE RIGHT ENTRANCE REGION
OF THE 100+ KT UPPER JET CORE CENTERED OVER THE NORTHEAST STATES...
AND ABOVE NORMAL PW (1.8-2.0 IN.) WILL ALL SUPPORT A CONTINUED
THREAT OF NUMEROUS SHOWERS AND STORMS IN THE EAST... WITH LESSER
COVERAGE IN THE WEST WITHIN LOWER PW AND SLIGHTLY MORE STABLE AIR
DUE TO THIS MORNING`S SHOWERS/CLOUDS. THIS SCENARIO IS SUPPORTED BY
THE LATEST HRRR GUIDANCE AS WELL AS THE WRF-ARW/NMM. CONCERN
PERSISTS FOR A FEW SEVERE STORMS INTO EARLY EVENING IN THE EASTERN
CWA (PARTICULARLY SOUTHEAST SECTIONS SE OF RALEIGH) WHERE MODERATE
INSTABILITY IS ALIGNED WITH DECENT DEEP LAYER EFFECTIVE SHEAR OF 25-
30 KTS... 500 MB WINDS OF 30-40 KTS... AND D-CAPE OF 800-1200 J/KG.
AS THE WEAKENING MID LEVEL SHEAR AXIS SHIFTS SLOWLY EASTWARD AND
OVERHEAD OVERNIGHT... STORM COVERAGE SHOULD SLOWLY SHRINK AS WE LOSE
HEATING... ENDING LAST OVER THE ERN COASTAL PLAIN... AS THE SURFACE
BOUNDARY SETTLES OVER SE NC. PLENTIFUL LOW LEVEL MOISTURE AND WEAK
MASS CONVERGENCE SHOULD RESULT IN POCKETS OF FOG/STRATUS AREAWIDE
OVERNIGHT. HIGH-RES GUIDANCE AND PERSISTENCE SUGGEST LOWS TONIGHT OF
67-73.
FOR FRI/FRI NIGHT: AS THE DAMPENING SHEAR AXIS SHIFTS TO OUR SE IN
LINE WITH THE DISSIPATING SURFACE TROUGH... THE HIGHER PW VALUES
WILL ACCORDINGLY SHIFT TO THE COASTAL PLAIN... LEAVING A LIGHT NNE
LOW LEVEL FLOW AND RELATIVELY (FOR JULY) DRY COLUMN OVER THE NRN AND
WRN CWA. MODELS GENERALLY INDICATE VERY LITTLE PRECIP COVERAGE...
CONFINING AFTERNOON CONVECTION TO THE COASTAL PLAIN AND SE SANDHILLS
WHERE MODELS PROJECT MUCAPE PEAKING AT 1000-1500 J/KG. WILL RETAIN
CHANCE POPS HERE WITH ISOLATED CHANCES TO THE NW. A DIP IN
THICKNESSES TO SLIGHTLY BELOW NORMAL VALUES SUPPORTS HIGHS OF 85-90.
EXPECT LITTLE MORE THAN PATCHY SHOWERS FRI NIGHT. LOWS 66-71. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 315 PM THURSDAY...
THE MID LEVEL TROUGH AXIS (CURRENTLY MOVING TOWARDS THE AREA) WILL
PUSH OFFSHORE ON SATURDAY...WHILE THE MID LEVEL RIDGE TRIES TO BUILD
EASTWARD TOWARDS THE REGION. MODELS HAVE TRENDED DRIER FOR THE
WEEKEND...ESPECIALLY ON SATURDAY GIVEN THE DRIER AIR FILTERING INTO
THE REGION BEHIND THE DEPARTING TROUGH. IN FACT...FORECAST SOUNDINGS
INDICATE VERY LIMITED DEEP LAYER MOISTURE...WITH PWAT VALUES PROGGED
TO RANGE BETWEEN 1-1.25 INCHES (WELL BELOW NORMAL). THEREFORE...
WILL GO WITH A MOSTLY DRY FORECAST FOR SATURDAY. MOISTURE WILL START
TO RECOVER SOME ON SUNDAY AND A SURFACE TROUGH WILL SHARPEN UP OVER
THE REGION...LEADING TO A BETTER CHANCE OF MOSTLY DIURNAL TYPE
STORMS...ALTHOUGH OVERALL COVERAGE SHOULD STILL BE RATHER LOW. LOW
LEVEL THICKNESS VALUES ARE PROGGED TO BE NEAR 1420M ON SATURDAY AND
GIVEN EXPECTED LACK OF PRECIP...TEMPS SHOULD RISE INTO THE UPPER 80S
TO LOWER 90S. BY SUNDAY...LOW LEVEL THICKNESS VALUES ARE EXPECTED TO
CLIMB ANOTHER 5-10M...RESULTING HIGH TEMPS A FEW DEGREES
WARMER...GENERALLY LOW TO MID 90S (ALTHOUGH MORE CLOUDS MAY BE
AROUND WHICH WOULD TEMPER THE WARMING SOME).
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 315 PM THURSDAY...
A DEEP VORTEX IS PROGGED TO MOVE SOUTH OUT OF CANADA AND EVENTUALLY
ACROSS THE GREAT LAKES THROUGH THE MIDDLE OF NEXT WEEK. THIS WILL
RESULT IN A DEEP TROUGH DEVELOPING OVER THE EASTERN HALF OF THE
CONUS. THEREFORE...PRECIP CHANCES WILL BE ON THE INCREASE FOR NEXT
WEEK...ESPECIALLY LATE TUESDAY INTO EARLY WEDNESDAY AS A FRONT
APPROACHES THE AREA. ALSO...GIVEN THIS UNSEASONABLY STRONG TROUGH...
THE MID LEVEL FLOW IS EXPECTED TO STRENGTHEN AND THEREFORE THE
POSSIBILITY OF AN ORGANIZED SEVERE THREAT WILL EXIST AND THIS WILL BE
MONITORED OVER THE NEXT SEVERAL DAYS. THEN THERE IS STILL A GOOD BIT
OF UNCERTAINTY WITH REGARDS TO IF THIS FRONT WILL PUSH ALL THE WAY
THROUGH THE AREA...BUT FOR NOW IT LOOKS LIKE THE FRONT WILL STALL
SOMEWHERE ACROSS THE CAROLINAS. THUS...WILL SHOW A LITTLE DECREASE
IN POPS FOR THE LATTER HALF OF THE WEEK...BUT WILL KEEP A CHANCE IN
GIVEN THE UNCERTAINTY WITH REGARDS TO WHERE THE FRONT ENDS UP. HIGH
TEMPS AHEAD OF THE FRONT ARE EXPECTED TO BE IN THE LOW TO MID 90S ON
MONDAY AND POSSIBLY TUESDAY...ALTHOUGH DEPENDING ON THE TIMING OF
THE PRECIP...TEMPS COULD BE SLIGHTLY LOWER ON TUESDAY. THEN SLIGHTLY
COOLER TEMPS ARE EXPECTED WEDNESDAY AND THURSDAY GIVEN THE DEEP
TROUGHING OVER THE EAST COAST AND THE POSSIBILITY THAT THE FRONT
WILL PUSH THROUGH THE AREA.
&&
AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1250 PM THURSDAY...
WHILE A FEW CLOUDS BASED AT 2000-3000 FT AGL PERSIST OVER CENTRAL
NC... VFR CONDITIONS ARE EXPECTED TO DOMINATE AT CENTRAL NC TERMINAL
SITES THROUGH 04Z THIS EVENING... ALTHOUGH A SHORT PERIOD OF MVFR
CIGS AND IFR VSBYS WITH HEAVY RAIN AND STRONG/VARIABLE WIND GUSTS
ARE POSSIBLE IN/NEAR SHOWERS/STORMS. STORMS COULD AFFECT TAF SITES
AT ANY TIME THROUGH MID EVENING BUT ARE MOST LIKELY TO IMPACT
INT/GSO IN THE 18Z-21Z WINDOW... RDU IN THE 20Z-02Z WINDOW... AND
FAY/RWI IN THE 21Z-04Z WINDOW. STARTING NEAR 04Z... SHOWERS AND
ISOLATED STORMS WITH SUB-VFR CONDITIONS MAY BE ONGOING NEAR RWI/FAY
AND PERHAPS RDU... ALTHOUGH COVERAGE SHOULD STEADILY SHRINK
OVERNIGHT. WIDESPREAD MVFR TO IFR FOG AND STRATUS ARE EXPECTED TO
FORM AFTER 06Z AND PERSIST UNTIL 12Z FRI MORNING... AFTER WHICH TIME
AN IMPROVEMENT TO VFR IS EXPECTED THROUGH 14Z. AWAY FROM STORMS...
PREVAILING WINDS WILL REMAIN LIGHT... UNDER 10 KTS... MAINLY FROM
THE S AND SW (EXCEPT VARIABLE AT INT/GSO).
LOOKING BEYOND 18Z FRI... VFR CONDITIONS WILL AGAIN DOMINATE BUT A
FEW STORMS WITH GUSTY WINDS AND SUB-VFR CONDITIONS ARE EXPECTED AT
RDU AND PARTICULARLY RWI/FAY FRI AFTERNOON/EVENING. ARRIVAL OF A
DRIER AND MORE STABLE AIR MASS FRI NIGHT THROUGH SUN WILL LEAD TO A
HIGH CONFIDENCE IN VFR CONDITIONS OVER THE WEEKEND. A RETURN TO
SCATTERED LATE DAY SHOWERS AND STORMS IS EXPECTED MON-TUE... WITH A
CHANCE OF LIGHT SUB-VFR FOG WITHIN A FEW HOURS OF DAWN BOTH MON AND
TUE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS/HARTFIELD
NEAR TERM...HARTFIELD/BLS
SHORT TERM...KRD
LONG TERM...KRD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
319 PM EDT WED JUL 9 2014
.SYNOPSIS...
A COLD FRONT WILL STALL OVER THE REGION LATE THURSDAY INTO EARLY
SATURDAY...BRINGING GOOD CHANCES FOR THUNDERSTORMS. THIS FRONT
WILL DISSIPATE LATE IN THE WEEKEND WITH A RETURN TO TYPICAL
SUMMERTIME CONDITIONS BY EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM WEDNESDAY...FINE CU FIELD BUILDING RIGHT ALONG SEA
BREEZE BOUNDARY AS IT MAKES ITS WAY INLAND THROUGH THIS
AFTERNOON...LEAVING TIP OF CAPE FEAR THE SUNNIEST SPOT. HRRR MODEL
FORECAST HOLDING WELL SO FAR AS BROKEN LINE OF CONVECTION
STREAMING FROM SOUTHWEST TO NORTHEAST JUST WEST OF FORECAST AREA.
MODELS SHOWED THIS LINE DIMINISHING AS IT PUSHES EASTWARD THROUGH
EARLY THIS EVENING. WILL KEEP POPS AS IS WITH POSSIBILITY OF AN
ISOLATED SHWR ALONG SEA BREEZE AND CHC POPS OVER INLAND COUNTIES
MAINLY LATER TODAY. DEW POINT TEMPS WILL HOLD IN THE MID 60S INLAND
THROUGH THIS AFTERNOON AND CLOSER TO 70 ALONG THE COAST IN A
CONTINUED SOUTHWEST FLOW OF WARM AND MOIST AIR AT THE SURFACE
AROUND BERMUDA HIGH. OVERALL VERY WARM DAY WITH SPOTTY CU FIELD
LEAVING A GOOD DEAL OF SUNSHINE AND TEMPS INTO THE 90S MOST
PLACES.
LATEST MOISTURE PROFILES KEEP VERY DRY MID LEVELS THROUGH MUCH OF
TONIGHT AS MID TO UPPER RIDGE HOLDS ON FOR ONE LAST DAY.
CONVECTIVE PARAMETERS BECOME MORE FAVORABLE THIS EVENING BUT
SUPPORT FOR CONVECTION WILL DIMINISH THROUGH THIS EVENING AS
HEATING OF THE DAY CUTS OFF. THE MAIN FOCUS FOR CONVECTION WILL
LIE MAINLY TO OUR WEST AS PIEDMONT TROUGH AND AN APPROACHING COLD
FRONT DRIVE MUCH OF THE CONVECTIVE ACTIVITY. A DEEPENING UPPER
TROUGH OVER EASTERN CONUS WILL PUSH EAST PROVIDING MUCH GREATER
SUPPORT FOR CONVECTION AND THIS MAY REACH FAR ENOUGH INTO THE
CAROLINAS BY THIS EVENING TO TRIGGER SOME SHWRS/TSTMS WHICH MAY
REACH INTO WESTERN REACHES OF FORECAST AREA BY THIS EVENING
THIS COLD FRONT WILL PUSH EAST WITH PLENTY OF MOISTURE POOLING
AHEAD OF IT AND INCREASED UPPER LEVEL SUPPORT HEADING INTO THURS.
MAY SEE SOME SHWRS/TSTMS AROUND OVERNIGHT INTO EARLY THURS BUT
MAIN ACTIVITY WILL COME LATER IN THE DAY. ANOTHER WARM NIGHT AHEAD
WITH TEMPS DROPPING BUT REMAINING IN THE 70S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...AN UPPER LEVEL TROUGH AND SURFACE COLD
FRONT WILL BE SHIFTING INTO THE AREA. AT THE SURFACE THIS FRONT
WILL STALL AND ABOVE THE SURFACE PRECIPTABLE WATERS WILL INCREASE
TO 2 PLUS INCHES. THE FLOW ALOFT WILL PARALLEL THE FRONT AND THE
850 TO 700 MB WINDS WILL BE AT 10 TO 15 KNOTS. EVEN HIGHER THE
UPPER LEVEL FORCING FROM THE 300 MB JET WILL INCREASE SYNOPTIC
SCALE LIFT. SO THE POSSIBILITY OF HEAVY RAIN OVER THE AREA
THURSDAY AFTERNOON THROUGH FRIDAY MIDDAY CONTINUE TO BE HIGH. BY FRIDAY
MIDDAY THE SYNOPTIC SCALE VORTICITY HAS SHIFTED OFFSHORE AND IT
WILL DRAG THE DEEPER MOISTURE WITH IT. EXPECT THE CHANCES FOR THE
HEAVY RAIN TO DIMINISHED AT THIS TIME.
MAXIMUM TEMPERATURES WILL REACH THE LOWER 90S ON THURSDAY IF THE
CONVECTION HOLD OFF AND CLOUDS AND RAIN DO NOT COOL THE ATMOSPHERE
TO QUICKLY. EXPECT HIGHS TO BE EVEN LOWER WITH CLOUDS AND RAIN
KEEP THE HIGHS AT BAY AND REACHING INTO THE UPPER 80S. LOW
TEMPERATURES WILL BE IN THE MID 70S THURSDAY NIGHT AND THE LOWER
70S FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...REMAINS OF COLD FRONT STILL SHOWING UP
STALLED ACROSS THE AREA ON SATURDAY. BETWEEN SOME UNCERTAINTY AS TO
WHERE IT STALLS PAIRED WITH MODEL DISAGREEMENT REGARDING WHICH SIDE
OF THE BOUNDARY IS FAVORED FOR PRECIP WILL STICK WITH PREVIOUS
AREA-WIDE 40-ISH POP. THE BOUNDARY WASHES OUT ON SUNDAY AND A VERY
WEAK PIEDMONT TROUGH MAY BE DEVELOPING. ITS STILL HARD TO SHOW ANY
PARTICULAR FAVORED AREA FOR POPS BUT WILL SHOW A SMALL DOWNWARD
TREND DUE TO SOME MID LEVEL DRYING. MONDAY SHOULD OFFER SEASONABLE
TEMPERATURES AND A SEASONABLE DISTRIBUTION OF DIURNAL CONVECTION AS
THE AREA FINDS ITSELF BETWEEN A VERY WEAK UPPER RIDGE OVER FL AND AN
UNSEASONABLY LARGE/STRONG VORTEX DROPPING INTO THE GREAT LAKES.
TUESDAY AND WEDNESDAY FEATURE A RETURN OF THE PIEDMONT TROUGH AND A
SLIGHT VEERING OF THE MID LEVEL FLOW FROM THE AFOREMENTIONED UPPER
LOW. RAINFALL CHANCES SHOULD INCREASE JUST SLIGHTLY WHILE TEMPS
REMAIN NEAR NORMAL.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...MODELS NOT IN GREAT AGREEMENT WITH RESPECT TO CONVECTION
THIS AFTERNOON. THE NAM IS MORE AGGRESSIVE IN BRINGING IN CONVECTION
TO THE WESTERN CWA LATE THIS AFTERNOON...WHEREAS THE GFS HAS LITTLE
OR NO CONVECTION AT ALL. WILL ADD VCTS TO THE WESTERN
TERMINALS...HOWEVER CONFIDENCE IS RATHER LOW. AREAS THAT RECEIVE
PRECIP THIS AFTERNOON COULD SEE SOME LIGHT FOG TOWARD MORNING.
THURSDAY...MORE ACTIVE WITH THE CONVECTION AS THE DRY AIR IN THE MID
LEVELS HAS PUSHED OFF THE COAST AND WE ARE IN A MORE FAVORABLE
REGIME FOR CONVECTION TO FIRE. BEST CHANCE WILL BE THE
AFTERNOON...HOWEVER COULD NOT RULE OUT A MORNING SHOWER.
EXTENDED OUTLOOK...A FRONT STALLS OVER THE REGION WITH A DECENT
CHANCE FOR CONVECTION THROUGH SATURDAY...MAINLY IN THE AFTERNOON.
MORE SHOWERS AND STORMS ARE POSSIBLE MONDAY. BRIEF IFR CONDITIONS
ARE POSSIBLE IN THE HEAVIER SHOWERS AND STORMS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM WEDNESDAY...SOUTHWESTERLY FLOW WILL CONTINUE OVER THE
WATERS THROUGH TONIGHT BETWEEN HIGH PRESSURE OVER THE WESTERN
ATLANTIC AND TROUGH OF LOW PRESSURE INLAND. SEAS WILL REMAIN BETWEEN
2 AND 4 FT AS GRADIENT WEAKENS THROUGH THE NIGHT LEAVING WINDS OF 15
KTS OR LESS.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...AS A COLD FRONT APPROACHES THE COAST LATE
THURSDAY THE SOUTHWEST WINDS WILL INCREASE TO 15 KNOTS BUT THE
WINDS WILL WEAKEN AS THE FRONTAL BOUNDARY STALLS AT THE COAST AND
THE PRESSURE GRADIENT WEAKENS FRIDAY. SEAS ARE EXPECTED TO BE
AROUND 3 FEET ON THURSDAY BUT WILL SLOWLY DIMINISH TO 2 FEET BY
FRIDAY NIGHT IN RESPONSE TO THE WINDS.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 PM WEDNESDAY...LIGHT WINDS EXPECTED ON SATURDAY WITH A
WEAKENING FRONT STALLED ACROSS THE AREA. THIS BOUNDARY WILL CAST A
SMALL DEGREE OF UNCERTAINTY WITH RESPECT TO WIND DIRECTION BUT
SOUTHERLY FLOW GENERALLY EXPECTED TO BE PREDOMINANT. THIS BOUNDARY
WASHES OUT BY SUNDAY AS A WEAK PIEDMONT TROUGH DEVELOPS. THIS MAY BE
GOOD FOR ABOUT A 5KT/1FT INCREASE IN CONDITIONS. A SIMILAR OR EVEN
LARGER INCREASE IN WINDS AND SEAS MAY BE SLATED FOR MONDAY. BROAD
CYCLONIC CURVATURE AROUND A LARGE STORM NORTH OF THE GREAT LAKES
RESPONSIBLE FOR TIGHTENING THE GRADIENT LOCALLY. HEADLINES OR EVEN
AND ADVISORY APPEAR POSSIBLE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...HAWKINS
LONG TERM...MBB
AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
206 PM EDT WED JUL 9 2014
.SYNOPSIS...
VERY WARM WEATHER WILL CONTINUE TODAY AS HIGH PRESSURE HOLDS ON. AN
APPROACHING COLD FRONT WILL STALL NEAR THE AREA THURSDAY AND
FRIDAY...BRINGING GOOD CHANCES FOR THUNDERSTORMS. THIS FRONT WILL
WASH OUT DURING THE WEEKEND WITH A RETURN TO TYPICAL SUMMERTIME
CONDITIONS...CONTINUING INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM WEDNESDAY...FINE CU FIELD BUILDING RIGHT ALONG SEA
BREEZE BOUNDARY AS IT MAKES ITS WAY INLAND THROUGH THIS
AFTERNOON...LEAVING TIP OF CAPE FEAR THE SUNNIEST SPOT. HRRR MODEL
FORECAST HOLDING WELL SO FAR AS BROKEN LINE OF CONVECTION
STREAMING FROM SOUTHWEST TO NORTHEAST JUST WEST OF FORECAST AREA.
MODELS SHOWED THIS LINE DIMINISHING AS IT PUSHES EASTWARD THROUGH
EARLY THIS EVENING. WILL KEEP POPS AS IS WITH POSSIBILITY OF AN
ISOLATED SHWR ALONG SEA BREEZE AND CHC POPS OVER INLAND COUNTIES
MAINLY LATER TODAY. DEWPOINT TEMPS WILL HOLD IN THE MID 60S INLAND
THROUGH THIS AFTERNOON AND CLOSER TO 70 ALONG THE COAST IN A
CONTINUED SOUTHWEST FLOW OF WARM AND MOIST AIR AT THE SURFACE AROUND
BERMUDA HIGH. OVERALL VERY WARM DAY WITH SPOTTY CU FIELD LEAVING A
GOOD DEAL OF SUNSHINE AND TEMPS INTO THE 90S MOST PLACES.
LATEST MOISTURE PROFILES KEEP VERY DRY MID LEVELS THROUGH MUCH OF
TONIGHT AS MID TO UPPER RIDGE HOLDS ON FOR ONE LAST DAY.
CONVECTIVE PARAMETERS BECOME MORE FAVORABLE THIS EVENING BUT
SUPPORT FOR CONVECTION WILL DIMINISH THROUGH THIS EVENING AS
HEATING OF THE DAY CUTS OFF. THE MAIN FOCUS FOR CONVECTION WILL
LIE MAINLY TO OUR WEST AS PIEDMONT TROUGH AND AN APPROACHING COLD
FRONT DRIVE MUCH OF THE CONVECTIVE ACTIVITY. A DEEPENING UPPER
TROUGH OVER EASTERN CONUS WILL PUSH EAST PROVIDING MUCH GREATER
SUPPORT FOR CONVECTION AND THIS MAY REACH FAR ENOUGH INTO THE
CAROLINAS BY THIS EVENING TO TRIGGER SOME SHWRS/TSTMS WHICH MAY
REACH INTO WESTERN REACHES OF FORECAST AREA BY THIS EVENING
THISCOLD FRONT WILL PUSH EAST WITH PLENTY OF MOISTURE POOLING
AHEAD OF IT AND INCREASED UPPER LEVEL SUPPORT HEADING INTO THURS.
MAY SEE SOME SHWRS/TSTMS AROUND OVERNIGHT INTO EARLY THURS BUT
MAIN ACTIVITY WILL COME LATER IN THE DAY. ANOTHER WARM NIGHT AHEAD
WITH TEMPS DROPPING BUT REMAINING IN THE 70S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM WEDNESDAY...THE END OF THE WEEK IS SET TO FEATURE
WIDESPREAD CONVECTION...HEAVY RAINFALL...AND SEASONABLE TEMPS...AS A
COLD FRONT GETS HUNG UP IN THE VICINITY. THIS FRONT WILL APPROACH
THE AREA THURSDAY...AND THEN GET HUNG UP LOCALLY AS THE VORT ENERGY
DRIVING IT HANGS WELL BACK WEST OF THE AREA. PWATS ARE FORECAST TO
RISE UP ABOVE 2 INCHES THURSDAY...WHICH COMBINED WITH SBCAPE ABOVE
1000 J/KG...SURFACE CONVERGENCE ALONG THE BOUNDARY...AND STRONG
DIFFLUENCE WITHIN THE RFQ OF A 100KT UPPER JET...SHOULD SUPPORT
WIDESPREAD TSTMS WITH POTENTIALLY HEAVY RAINFALL. ON FRIDAY...THE
SETUP REMAINS VERY SIMILAR...UNTIL THE ASSOCIATED SHORTWAVE AND
SHEAR AXIS FINALLY SWINGS EAST...CAUSING SLOWLY DRYING MID-LEVELS ON
W/NW FLOW. THE SURFACE FRONT BECOMES WASHED OUT...AND NEVER REALLY
CROSSES FULLY OFFSHORE...AND THUS WILL CONTINUE TO SERVE AS A FOCUS
FOR WIDESPREAD CONVECTION...WITH HIGHER POP WARRANTED ACROSS EASTERN
ZONES THAN ON THURSDAY. LATE IN THE PERIOD CONVECTION WILL BEGIN TO
WANE AS MORE SIGNIFICANT DRYING OF THE MID-LEVELS OCCURS...AS
CLEARLY EVIDENT ON FORECAST PROFILES FRIDAY NIGHT.
TEMPS THURSDAY WILL RISE INTO THE LOW 90S AHEAD OF THE COLD
FRONT...BUT REMAIN COOLER THAN WEDNESDAY THANKS TO CLOUD COVER AND
RAINFALL. FRIDAY WILL BE A FEW DEGREES COOLER STILL THANKS TO MORE
SIGNIFICANT CLOUD COVER AND COOLER THICKNESSES. MINS THURSDAY NIGHT
WILL BE WELL ABOVE NORMAL...MID 70S...BEFORE FALLING TO SEASONABLE
VALUES AROUND 70 ON FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...SUBTLE RIDGING ALOFT FOR THE WEEKEND WILL
CREATE A DRYING TREND SAT/SUN WITH SEASONABLE TEMPS ACROSS THE AREA.
ALTHOUGH MID-LEVEL RIDGE BLOSSOMS FROM THE SOUTH...IT BECOMES STRUNG
OUT WEST-TO-EAST THANKS TO DEVELOPING NORTHERN STREAM
TROUGHING...AND WILL STRUGGLE TO WARM THE AREA...LEAVING TEMPS
AROUND CLIMO NORMS. AT THE SURFACE...HIGH PRESSURE CENTERED WELL OFF
THE ATLANTIC SEABOARD WILL RIDGE BACK TOWARDS THE COAST...KEEPING
WARM/MOIST RETURN FLOW FLOODING INTO THE AREA...AND THUS EVEN THOUGH
MID-LEVELS WILL BE DRY...TYPICAL DIURNAL CONVECTION IS EXPECTED EACH
DAY DURING THE WKND. THE AFOREMENTIONED TROUGH THEN DIVES INTO THE
SOUTHEAST EARLY NEXT WEEK...DRIVING A COLD FRONT AND HEIGHT FALLS
INTO THE CAROLINAS...WHICH WILL BE ACCOMPANIED BY INCREASING COLUMN
MOISTURE AND...EXPECTANTLY...INCREASING POP FOR EARLY NEXT WEEK.
HIGHS INTO NEXT WEEK WILL REMAIN AROUND OR SLIGHTLY ABOVE
CLIMO...BUT LOWS WILL BE SEVERELY TEMPERED BY RETURN FLOW AND CLOUD
COVER...REMAINING SOLIDLY ABOVE NORMAL.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...MODELS NOT IN GREAT AGREEMENT WITH RESPECT TO CONVECTION
THIS AFTERNOON. THE NAM IS MORE AGGRESSIVE IN BRINGING IN CONVECTION
TO THE WESTERN CWA LATE THIS AFTERNOON...WHEREAS THE GFS HAS LITTLE
OR NO CONVECTION AT ALL. WILL ADD VCTS TO THE WESTERN
TERMINALS...HOWEVER CONFIDENCE IS RATHER LOW. AREAS THAT RECEIVE
PRECIP THIS AFTERNOON COULD SEE SOME LIGHT FOG TOWARD MORNING.
THURSDAY...MORE ACTIVE WITH THE CONVECTION AS THE DRY AIR IN THE MID
LEVELS HAS PUSHED OFF THE COAST AND WE ARE IN A MORE FAVORABLE
REGIME FOR CONVECTION TO FIRE. BEST CHANCE WILL BE THE
AFTERNOON...HOWEVER COULD NOT RULE OUT A MORNING SHOWER.
EXTENDED OUTLOOK...A FRONT STALLS OVER THE REGION WITH A DECENT
CHANCE FOR CONVECTION THROUGH SATURDAY...MAINLY IN THE AFTERNOON.
MORE SHOWERS AND STORMS ARE POSSIBLE MONDAY. BRIEF IFR CONDITIONS
ARE POSSIBLE IN THE HEAVIER SHOWERS AND STORMS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM WEDNESDAY...SOUTHWESTERLY FLOW WILL CONTINUE OVER THE
WATERS THROUGH TONIGHT BETWEEN HIGH PRESSURE OVER THE WESTERN
ATLANTIC AND TROUGH OF LOW PRESSURE INLAND. SEAS WILL REMAIN BETWEEN
2 AND 4 FT AS GRADIENT WEAKENS THROUGH THE NIGHT LEAVING WINDS OF 15
KTS OR LESS.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM WEDNESDAY...A COLD FRONT APPROACHING FROM THE WEST WILL
STALL BEFORE REACHING THE COASTAL WATERS ON THURSDAY...AND THEN WASH
OUT ACROSS THE REGION FRIDAY. THIS CREATES A PINCHED GRADIENT
THURSDAY...WITH SW WINDS AROUND 15 KTS COMMON ON THURSDAY. THESE
WINDS WILL BACK MORE TO THE SOUTH ON FRIDAY...WHILE DECREASING IN
SPEED TO AROUND 10 KTS AS THE GRADIENT WEAKENS NEAR THE DISSIPATING
BOUNDARY. SEAS DURING THE SHORT TERM WILL BE HIGHEST THURSDAY ON THE
STRONGER WINDS...REACHING 3-4 FT WITH A SW WIND CHOP THE PRIMARY
WAVE GROUP. ON FRIDAY THESE WILL FALL TO 2-3 FT WITH A MORE
SOUTHERLY WIND WAVE DEVELOPING.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 330 AM WEDNESDAY...A FAIRLY TYPICAL SUMMERTIME PATTERN
EXPECTED FOR THE WKND AS HIGH PRESSURE CENTERED WELL OFFSHORE RIDGES
BACK TOWARDS THE COASTAL WATERS. WHILE THE SW WINDS THIS CREATES
WILL INITIALLY BE LIGHT...AROUND 10 KTS...THEY WILL RISE SLOWLY
THROUGH THE PERIOD TO 15-20 KTS LATE SUNDAY. AN INCREASING SE GROUND
SWELL AND SW WIND WAVE WILL DRIVE SEAS UPWARD THROUGH THE WKND AS
WELL...FROM 1-3 FT EARLY SATURDAY...TO 3-4 FT BY THE END OF THE
EXTENDED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...DL
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1008 AM EDT WED JUL 9 2014
.SYNOPSIS...
A SECONDARY COLD FRONT WILL MOVE ACROSS THE REGION TODAY.
HIGH PRESSURE WILL BUILD OVER THE AREA WEDNESDAY NIGHT AND
REMAIN THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLOUDS WERE EXPANDING DURING THE MID/LATE MORNING ACROSS NE OH/NW
PA AND WILL CONTINUE TO DO SO WITH THE DAY TIME HEATING AND AHEAD
OF THE WEAK COLD FRONT/TROUGH NEAR LAKE ERIE. A FEW SHOWERS AND
THUNDERSTORMS DEVELOPED OVER LAKE ERIE ALONG THE MID LAKE
CONVERGENCE ZONE. THIS LINE OF SHOWERS WILL MOVE ONSHORE AND
PROBABLY REDEVELOP INTO A WIDELY SCATTERED RAIN SHOWER PATTERN BY
THE AFTERNOON. OTHER RANDOM SHOWERS/STORMS WILL POP UP BUT WITH A
FAIR AMOUNT OF DRY AIR IN THE LOWER LAYERS THE COVERAGE WILL NOT
EVER BECOME VERY SIGNIFICANT.
PREVIOUS "TODAY" DISCUSSION...
AS THE SECONDARY COLD FRONT MOVES ACROSS THE FORECAST AREA
TODAY...WE CAN EXPECT SCATTERED SHOWERS AND THUNDERSTORMS. THE
MODELS INDICATE THE BEST INSTABILITY WILL BE OVER NE OHIO AND NW
PA THIS AFTERNOON. THE HRRR AND SREF AGREE WITH THIS SCENARIO. I
WILL KEEP A SLIGHTLY HIGHER POP FORECAST OVER THIS AREA BUT WILL
NOT RULE OUT A CHANCE OF TSTMS ANYWHERE THIS AFTERNOON. GUIDANCE
TEMPERATURES APPEAR TO BE REASONABLE AND I WILL NOT STRAY FAR FROM
THEM.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
HIGH PRESSURE WILL DOMINATE THE SHORT TERM PERIOD. A DRY
FORECAST WITH SEASONABLE TEMPERATURES IS EXPECTED THROUGH FRIDAY.
TEMPERATURES WILL BE WARMING ON FRIDAY AND SATURDAY AS A WARM FRONT
PUSHES THROUGH THE FORECAST AREA. THE CURRENT FORECAST APPEARS TO
HANDLE THE CONVECTIVE TREND WELL FOR THE WEEKEND. BOTH THE NAM AND
GFS SUGGEST SHOWERS MAY MOVE INTO NW OHIO BY 12Z SATURDAY.
SCATTERED SHOWERS SHOULD BE OVER MOST OF THE FORECAST AREA
SATURDAY AFTERNOON AND SATURDAY NIGHT AS A COLD FRONT APPROACHES
FROM THE WEST.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
A LONG WAVE TROUGH WILL REMAIN OVER THE EASTERN U.S. DURING THE
PERIOD KEEPING THE LOCAL AREA IN AN ACTIVE WEATHER PATTERN. A
FRONTAL SYSTEM WILL IMPACT THE REGION ON SUNDAY AND MONDAY. THERE
WILL BE PRETTY GOOD CHANCES FOR THUNDERSTORMS BOTH DAYS. THE FRONT
WILL FINALLY PUSH TO THE SOUTH FOR GOOD ON MONDAY NIGHT. THERE
COULD BE A FEW INSTABILITY SHOWERS MONDAY NIGHT BUT WILL TRY FOR DRY
WEATHER ON TUESDAY. TEMPERATURES WILL BE SEASONABLE BOTH SUNDAY AND
MONDAY BUT BELOW NORMAL ON TUESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THE AIR MASS OVER THE REGION IS A LITTLE DRIER THAN EXPECTED SO
SKIES HAVE CLEARED OVERNIGHT. STILL EXPECTING SCT TO BKN CU TO
DEVELOP LATER THIS MORNING. A FEW SHOWERS WILL BE POSSIBLE AS WELL
ALTHOUGH CONFIDENCE IS TOO LOW TO JUSTIFY INCLUDING IN THE TAFS.
SKIES SHOULD CLEAR TOWARD EVENING. LIGHT SW FLOW WILL BECOME W TO
NW BY MIDDAY.
OUTLOOK...NON VFR AGAIN POSSIBLE LATE FRIDAY NIGHT THROUGH SUNDAY
IN THUNDERSTORMS.
&&
.MARINE...
THE REMAINING SMALL CRAFT IS GONE AND WILL LIKELY NOT NEED ANOTHER
ONE THROUGH THE END OF THE PERIOD. A FRONT WILL CROSS THE LAKE
TODAY CAUSING THE FLOW TO BECOME NORTHWEST. SPEEDS FOR THE MOST
PART WILL BE 10 KNOTS OR LESS. EXPECT THE FLOW TO BECOME LIGHT AND
VARIABLE TONIGHT AND EVENTUALLY LIGHT NORTHEAST ON THURSDAY AS HIGH
PRESSURE MOVES TO THE NORTH OF THE LAKE. WINDS WILL EVENTUALLY TAKE
ON A SOUTHERLY COMPONENT FRIDAY NIGHT AND SATURDAY AS THE SURFACE
RIDGE FINALLY MOVES OFF TO THE EAST. A WARM FRONT WILL MOVE TOWARD
THE LAKE AT THE VERY END OF THE PERIOD CAUSING THE FLOW TO BECOME
MORE SOUTHWEST. SPEEDS THE ENTIRE PERIOD SHOULD BE UNDER 15 KNOTS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GARNET/KOSARIK
NEAR TERM...GARNET/KOSARIK
SHORT TERM...GARNET
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
731 AM EDT WED JUL 9 2014
.SYNOPSIS...
A SECONDARY COLD FRONT WILL MOVE ACROSS THE REGION TODAY.
HIGH PRESSURE WILL BUILD OVER THE AREA WEDNESDAY NIGHT AND
REMAIN THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A FEW MINOR CHANGES TO THE POP FORECAST AND THE TEMPERATURES TO
REFLECT THE CURRENT TRENDS. NO OTHER CHANGES.
PREVIOUS DISCUSSION...
SCATTERED SHOWERS AND A FEW THUNDERSTORMS CONTINUE OVER
NE OHIO AND NW PA EARLY THIS MORNING. THESE SHOWERS SHOULD
CONTINUE TO DECREASE IN COVERAGE TOWARDS DAY BREAK. AS THE
SECONDARY COLD FRONT MOVES ACROSS THE FORECAST AREA TODAY...WE CAN
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS. THE MODELS INDICATE
THE BEST INSTABILITY WILL BE OVER NE OHIO AND NW PA THIS
AFTERNOON. THE HRRR AND SREF AGREE WITH THIS SCENARIO. I WILL KEEP
A SLIGHTLY HIGHER POP FORECAST OVER THIS AREA BUT WILL NOT RULE
OUT A CHANCE OF TSTMS ANYWHERE THIS AFTERNOON. GUIDANCE
TEMPERATURES APPEAR TO BE REASONABLE AND I WILL NOT STRAY FAR FROM
THEM.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
HIGH PRESSURE WILL DOMINATE THE SHORT TERM PERIOD. A DRY
FORECAST WITH SEASONABLE TEMPERATURES IS EXPECTED THROUGH FRIDAY.
TEMPERATURES WILL BE WARMING ON FRIDAY AND SATURDAY AS A WARM FRONT
PUSHES THROUGH THE FORECAST AREA. THE CURRENT FORECAST APPEARS TO
HANDLE THE CONVECTIVE TREND WELL FOR THE WEEKEND. BOTH THE NAM AND
GFS SUGGEST SHOWERS MAY MOVE INTO NW OHIO BY 12Z SATURDAY.
SCATTERED SHOWERS SHOULD BE OVER MOST OF THE FORECAST AREA
SATURDAY AFTERNOON AND SATURDAY NIGHT AS A COLD FRONT APPROACHES
FROM THE WEST.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
A LONG WAVE TROUGH WILL REMAIN OVER THE EASTERN U.S. DURING THE
PERIOD KEEPING THE LOCAL AREA IN AN ACTIVE WEATHER PATTERN. A
FRONTAL SYSTEM WILL IMPACT THE REGION ON SUNDAY AND MONDAY. THERE
WILL BE PRETTY GOOD CHANCES FOR THUNDERSTORMS BOTH DAYS. THE FRONT
WILL FINALLY PUSH TO THE SOUTH FOR GOOD ON MONDAY NIGHT. THERE
COULD BE A FEW INSTABILITY SHOWERS MONDAY NIGHT BUT WILL TRY FOR DRY
WEATHER ON TUESDAY. TEMPERATURES WILL BE SEASONABLE BOTH SUNDAY AND
MONDAY BUT BELOW NORMAL ON TUESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THE AIRMASS OVER THE REGION IS A LITTLE DRIER THAN EXPECTED SO
SKIES HAVE CLEARED OVERNIGHT. STILL EXPECTING SCT TO BKN CU TO
DEVELOP LATER THIS MORNING. A FEW SHOWERS WILL BE POSSIBLE AS WELL
ALTHOUGH CONFIDENCE IS TOO LOW TO JUSTIFY INCLUDING IN THE TAFS.
SKIES SHOULD CLEAR TOWARD EVENING. LIGHT SW FLOW WILL BECOME W TO
NW BY MIDDAY.
OUTLOOK...NON VFR AGAIN POSSIBLE LATE FRIDAY NIGHT THROUGH SUNDAY
IN THUNDERSTORMS.
&&
.MARINE...
THE REMAINING SMALL CRAFT IS GONE AND WILL LIKELY NOT NEED ANOTHER
ONE THROUGH THE END OF THE PERIOD. A FRONT WILL CROSS THE LAKE
TODAY CAUSING THE FLOW TO BECOME NORTHWEST. SPEEDS FOR THE MOST
PART WILL BE 10 KNOTS OR LESS. EXPECT THE FLOW TO BECOME LIGHT AND
VARIABLE TONIGHT AND EVENTUALLY LIGHT NORTHEAST ON THURSDAY AS HIGH
PRESSURE MOVES TO THE NORTH OF THE LAKE. WINDS WILL EVENTUALLY TAKE
ON A SOUTHERLY COMPONENT FRIDAY NIGHT AND SATURDAY AS THE SURFACE
RIDGE FINALLY MOVES OFF TO THE EAST. A WARM FRONT WILL MOVE TOWARD
THE LAKE AT THE VERY END OF THE PERIOD CAUSING THE FLOW TO BECOME
MORE SOUTHWEST. SPEEDS THE ENTIRE PERIOD SHOULD BE UNDER 15 KNOTS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
608 AM EDT WED JUL 9 2014
.SYNOPSIS...
A SECONDARY COLD FRONT WILL MOVE ACROSS THE REGION TODAY.
HIGH PRESSURE WILL BUILD OVER THE AREA WEDNESDAY NIGHT AND
REMAIN THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A FEW MINOR CHANGES TO THE POP FORECAST AND THE TEMPERATURES TO
REFLECT THE CURRENT TRENDS. NO OTHER CHANGES.
PREVIOUS DISCUSSION...
SCATTERED SHOWERS AND A FEW THUNDERSTORMS CONTINUE OVER
NE OHIO AND NW PA EARLY THIS MORNING. THESE SHOWERS SHOULD
CONTINUE TO DECREASE IN COVERAGE TOWARDS DAY BREAK. AS THE
SECONDARY COLD FRONT MOVES ACROSS THE FORECAST AREA TODAY...WE CAN
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS. THE MODELS INDICATE
THE BEST INSTABILITY WILL BE OVER NE OHIO AND NW PA THIS
AFTERNOON. THE HRRR AND SREF AGREE WITH THIS SCENARIO. I WILL KEEP
A SLIGHTLY HIGHER POP FORECAST OVER THIS AREA BUT WILL NOT RULE
OUT A CHANCE OF TSTMS ANYWHERE THIS AFTERNOON. GUIDANCE
TEMPERATURES APPEAR TO BE REASONABLE AND I WILL NOT STRAY FAR FROM
THEM.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
HIGH PRESSURE WILL DOMINATE THE SHORT TERM PERIOD. A DRY
FORECAST WITH SEASONABLE TEMPERATURES IS EXPECTED THROUGH FRIDAY.
TEMPERATURES WILL BE WARMING ON FRIDAY AND SATURDAY AS A WARM FRONT
PUSHES THROUGH THE FORECAST AREA. THE CURRENT FORECAST APPEARS TO
HANDLE THE CONVECTIVE TREND WELL FOR THE WEEKEND. BOTH THE NAM AND
GFS SUGGEST SHOWERS MAY MOVE INTO NW OHIO BY 12Z SATURDAY.
SCATTERED SHOWERS SHOULD BE OVER MOST OF THE FORECAST AREA
SATURDAY AFTERNOON AND SATURDAY NIGHT AS A COLD FRONT APPROACHES
FROM THE WEST.
&&
.LONG TERM /SUNDAY THROUGH TUESDAY/...
A LONG WAVE TROUGH WILL REMAIN OVER THE EASTERN U.S. DURING THE
PERIOD KEEPING THE LOCAL AREA IN AN ACTIVE WEATHER PATTERN. A
FRONTAL SYSTEM WILL IMPACT THE REGION ON SUNDAY AND MONDAY. THERE
WILL BE PRETTY GOOD CHANCES FOR THUNDERSTORMS BOTH DAYS. THE FRONT
WILL FINALLY PUSH TO THE SOUTH FOR GOOD ON MONDAY NIGHT. THERE
COULD BE A FEW INSTABILITY SHOWERS MONDAY NIGHT BUT WILL TRY FOR DRY
WEATHER ON TUESDAY. TEMPERATURES WILL BE SEASONABLE BOTH SUNDAY AND
MONDAY BUT BELOW NORMAL ON TUESDAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
SHOWERS WITH EMBEDDED THUNDER CONTINUE TO MOVE ACROSS THE CENTRAL
PORTION OF THE AREA. SOME OF THESE SHOWERS MAY CLIP THE EASTERN
TAF SITES THE NEXT FEW HOURS. EXPECTING WIDESPREAD MVFR FOG TO
DEVELOP LATER TONIGHT WITH PATCHY MVFR CIGS AS WELL. MAINLY VFR
CIGS ARE EXPECTED DURING THE DAYLIGHT HOURS. SOME SCATTERED
SHOWERS ARE POSSIBLE BY LATE MORNING IN THE EAST. DRIER AIR WILL
FINALLY BEGIN TO WIN OUT DURING THE AFTERNOON WITH SKIES GOING
SCATTERED FROM WEST TO EAST BEGINNING AROUND MID AFTERNOON. SW
FLOW WILL BECOME W TO NW AFTER 12Z.
OUTLOOK...NON VFR AGAIN POSSIBLE LATE FRIDAY NIGHT THROUGH SUNDAY
IN THUNDERSTORMS.
&&
.MARINE...
THE REMAINING SMALL CRAFT IS GONE AND WILL LIKELY NOT NEED ANOTHER
ONE THROUGH THE END OF THE PERIOD. A FRONT WILL CROSS THE LAKE
TODAY CAUSING THE FLOW TO BECOME NORTHWEST. SPEEDS FOR THE MOST
PART WILL BE 10 KNOTS OR LESS. EXPECT THE FLOW TO BECOME LIGHT AND
VARIABLE TONIGHT AND EVENTUALLY LIGHT NORTHEAST ON THURSDAY AS HIGH
PRESSURE MOVES TO THE NORTH OF THE LAKE. WINDS WILL EVENTUALLY TAKE
ON A SOUTHERLY COMPONENT FRIDAY NIGHT AND SATURDAY AS THE SURFACE
RIDGE FINALLY MOVES OFF TO THE EAST. A WARM FRONT WILL MOVE TOWARD
THE LAKE AT THE VERY END OF THE PERIOD CAUSING THE FLOW TO BECOME
MORE SOUTHWEST. SPEEDS THE ENTIRE PERIOD SHOULD BE UNDER 15 KNOTS.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GARNET
NEAR TERM...GARNET
SHORT TERM...GARNET
LONG TERM...KUBINA
AVIATION...KUBINA
MARINE...KUBINA
AREA FORECAST DISCUSSION
NWS NORMAN OK
305 PM CDT WED JUL 9 2014
.DISCUSSION...
OVERNIGHT/MORNING CONVECTION HAS MAINLY DISSIPATED THIS AFTERNOON
WITH THE EXCEPTION OF A FEW SHOWERS IN SOUTH CENTRAL OKLAHOMA. NEW
CONVECTION IS DEVELOPING IN NORTH TEXAS ALONG A STALLED FRONTAL
BOUNDARY. CU FIELD EXTENDS FROM THIS DEVELOPING CONVECTION INTO THE
TEXAS PANHANDLE NEAR AMARILLO. RECENT HRRR RUNS...DEVELOP STORMS IN
THE CENTRAL TEXAS PANHANDLE AND MOVE STORMS GENERALLY EAST DURING
THE LATE AFTERNOON/EARLY EVENING. BASED ON CURRENT TRENDS...THIS
SEEM PLAUSIBLE.
OTHER STORMS ARE EXPECTED TO FORM IN WESTERN NEBRASKA/KANSAS IN
ADVANCE OF A SHORTWAVE. THIS ACTIVITY IS EXPECTED ENTER NORTHERN
OKLAHOMA DURING THE LATE EVENING/OVERNIGHT. WILL KEEP HIGHEST POPS
ACROSS NORTH CENTRAL OKLAHOMA.
OVERNIGHT CONVECTION MAY LINGER INTO THURSDAY MORNING...THEN A
BUILDING RIDGE ACROSS THE SOUTHERN PLAINS SHOULD GREATLY REDUCE
RAIN/STORM CHANCES. HOT WEATHER WILL BE THE RULE OVER THE WEEKEND.
NOT SURE IF HEAT ADVISORIES WILL BE NECESSARY AT THIS TIME.
BY TUESDAY OF NEXT WEEK...MOST MODELS PUSH A SIGNIFICANT FRONT INTO
OKLAHOMA AND NORTH TEXAS (AT LEAST BY JULY STANDARDS). THE FRONT
ALONG WITH A DECENT WAVE...MAY RESULT IN WIDESPREAD PRECIPITATION
TUESDAY NIGHT INTO WEDNESDAY.
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
542 PM EDT WED JUL 9 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL PUSH THROUGH THE AREA TONIGHT AND REMAINS IN
PLACE THURSDAY BEFORE WASHING OUT BY FRIDAY. WEAK HIGH PRESSURE WILL
RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 530 PM...A LARGE CLUSTER OF THUNDERSTORMS WAS PUSHING ACROSS
THE I-77 CORRDIOR. I WILL UPDATE THE FORECAST TO INCREASE POPS OVER
THE NEXT TWO HOURS ACROSS THE CLT METRO AREA. OUTFLOW GOVERNED
TEMPERATURES WILL REMAIN CHALLENGING THROUGH THE EVENING...I WILL
UPDATE WITH OBS.
AT 215PM...MOST THUNDERSTORM COVERAGE AT MID AFTERNOON IS ACROSS THE
SOUTHERN UPSTATE EASTWARD INTO NC. NUMEROUS STORMS DEVELOPED IN A
DIFFERENTIAL HEATING AXIS CREATED BY CLOUD COVER TO NORTH EARLIER
TODAY. PLUS THE LEE TROF HAS PROVIDED SOME LOW LEVEL CONVERGENCE. AN
UPPER SHORT WAVE DEPICTED BY THE RAP IS ALSO CROSSING THE AREA.
SHOULD SEE SOME ADDITIONAL DEVELOPMENT ACROSS THE NC
MOUNTAINS/FOOTHILLS PER CAMS SO WILL CONTINUE WITH SCT TYPE POPS
THOSE AREAS. SHOULD SEE THE COVERAGE OF CONVECTION WANE THIS EVENING
AS S/W MOVES TO THE E. HOWEVER...A COLD FRONT JUST WEST OF THE
APPALACHIANS IS FORECAST TO MOVE INTO THE NC MOUNTAINS THIS EVENING
WHICH COULD KICK OFF SOME ADDITIONAL SHOWERS/THUNDERSTORMS...SO WILL
SHOW AN UPTICK IN POPS OVER THE WEST THIS EVENING AGAIN. THE 12Z GFS
SEEMS TO HAVE SOME CONVECTIVE FEEDBACK OVER FAR WESTERN NC IN THE
00Z-06Z TIMEFRAME AND WILL NOT BUY INTO THE HIGH GFS QPF DEPICTED
THERE.
ON THU...THE FRONT IS FORECAST TO REACH THE PIEDMONT. THE MODELS
DEPICT A WEAK WAVE DEVELOPING ON THE BOUNDARY WHICH SHOULD TEND TO
ENHANCE THE COVERAGE NEAR IT. PLUS...ANOTHER WEAK SHORT WAVE IS
FORECAST TO CROSS THE AREA. HENCE...WILL STAY WITH THE IDEA OF
SCT-NUMEROUS SHOWERS/STORMS ACROSS THE PIEDMONT DURING THE
AFTERNOON...WITH LOWER POPS TO THE NORTH. SOUNDINGS LOOK MORE
SATURATED WITH LESS DCAPE...SO DO NOT EXPECT MUCH IN THE WAY OF A
SEVERE THREAT. MAX TEMPS ARE FORECAST TO BE ABOUT A CATEGORY BELOW
CLIMO.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 100 PM WEDNESDAY...THE SHORT TERM PERIOD INITIALIZES THURSDAY
EVENING WITH A QUASI STATIONARY FRONTAL BOUNDARY POSITIONED JUST
SOUTH OF INTERSTATE 85 INTO THE MIDLANDS OF SC...STRETCHING
NORTHEASTWARD INTO CENTRAL NC. SCATTERED CONVECTION WILL LIKELY BE
ONGOING AS HEATING WILL HAVE STEEPENED LAPSE RATES IN PROXIMITY TO
THE SURFACE BOUNDARY...WHICH WILL PROVIDE A FOCUS FOR SAID
CONVECTION. MEANWHILE...POSITIVELY TILTED UPPER TROF WILL BE
LIFTING TO THE NORTHEAST ALLOWING H5 HEIGHTS TO RISE. POPS WILL
TAPER DOWN DUE TO RISING HEIGHTS ALOFT AND HEATING LOSS INTO THE
OVERNIGHT HOURS OF FRIDAY MORNING. LATEST GUIDANCE INDICATES
POTENTIAL WEAK MESOLOW DEVELOPMENT ALONG THE FL PANHANDLE ON FRIDAY
MORNING ALLOWING FOR ENHANCED SOUTHEASTERLY FLOW INTO THE
CAROLINAS. THIS COMBINED WITH FLOW AROUND THE WESTERN ATLANTIC
SURFACE RIDGE WILL ALLOW THE STALLED FRONTAL BOUNDARY TO GRADUALLY
LIFT NORTHWARD TOWARDS THE CWFA INTO THE LATE AFTERNOON HOURS.
MOISTURE CONVERGENCE ALONG THIS BOUNDARY WILL PROVIDE A FOCUS FOR
CONVECTION ACROSS THE NC/SC PIEDMONT WHERE STEEPENING LAPSE RATES
AND INCREASED MOISTURE YIELD SBCAPE VALUES IN EXCESS OF 1500J/KG.
THUS WILL FAVOR LOW END CHANCE LEVEL POPS ACROSS THE PIEDMONT...AND
ALSO ALONG THE HIGH TERRAIN WHERE EAST SOUTHEAST UPSLOPE FLOW AIDS
CONVECTION. SLIGHT CHANCE POPS WILL OVERSPREAD THE REMAINDER OF THE
FORECAST AREA BEFORE DIURNAL COOLING WARRANTS TAPERED POPS ACROSS
THE ENTIRE REGION FOR THE OVERNIGHT.
SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE NORTHEAST
INTO THE WEEKEND...AND WILL EXTEND SOUTHWARD INTO THE
SOUTHERN/CENTRAL APPS. THIS COMBINED WITH RISING HEIGHTS ALOFT
WILL LIMIT CONVECTION EARLY ON SATURDAY BEFORE WEAK CIN IS OVERCOME
BY HEATING. EXPECTING INITIATION TO OCCUR ACROSS THE HIGH TERRAIN
ON SATURDAY AFTERNOON BEFORE WEAK NW FLOW ALOFT PROPAGATES SHOWERS
AND THUNDERSTORMS SOUTHEAST INTO THE FOOTHILLS/PIEDMONT REGIONS OF
NC/SC. DIURNALLY FAVORED LOW/MID LEVEL CHANCE POPS WILL HIGHLIGHT
THE FORECAST FOR SATURDAY. TEMPERATURES THROUGH THE SHORT TERM
PERIOD WILL BE AT OR JUST SLIGHTLY BELOW CLIMO.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 245 PM EDT TUE...THE LATEST GLOBAL MODELS CONTINUE TO INDICATE
THAT UPPER H5 HEIGHTS WILL FALL ACROSS THE SOUTHEAST SAT NIGHT INTO
SUN AS AN UPPER RIDGE OF HIGH AMPLIFIES OVER THE WESTERN CONUS WHILE
AN UPPER LOW PRESSURE TROUGH APPROACHES THE GREAT LAKES REGION FROM
SOUTH CENTRAL CANADA. THIS TROUGH IS EXPECTED TO SWING ACROSS THE
EASTERN STATES MON THROUGH WED.
AT THE SURFACE...BERMUDA HIGH WILL PERSIST THROUGH SUN BEFORE
SHIFTING TO THE EAST BY EARLY MON AS A COLD FRONT APPROACHES FROM
THE NW. THE FRONT IS EXPECTED TO CROSS THE AREA THROUGH MON NIGHT
FOLLOWED BY ANOTHER FRONT ON TUE. THE FRONT WILL REMAIN SOUTH OF THE
AREA WED AS A CONTINENTAL HIGH BUILDS IN FROM THE NW. AS FOR OUR
SENSIBLE WEATHER...POPS REMAIN NEAR CLIMO EACH DAY GIVEN LITTLE TO
NO CAPPING ALOFT AND SEASONABLY UNSTABLE AIRMASS DURING THE PEAK
HEATING HOURS. TEMPERATES WILL REMAIN NEAR...OR A FEW DEGREES BELOW
NORMAL THROUGH THE PERIOD.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
A CLT...MAIN CONCERN AS USUAL THIS TIME OF YEAR IS WHEN AND IF THE
AIRFIELD WILL SEE THUNDER. MOST CONVECTION AT THE MOMENT REMAINS SOUTH
OF THE AIRPORT. HOWEVER...MOST MESO MODELS BLOW UP CONVECTION OVER
CLT IN THE 20Z-00Z TIMEFRAME. HENCE...WILL CARRY A TEMPO FOR TSRA
DURING THAT TIME ALONG WITH RESTRICTIONS. CONVECTION SHOULD WANE
THIS EVENING LEAVING JUST VFR TYPE CEILINGS.
ELSEWHERE...THUNDERSTORMS COULD AFFECT ANY OF THE AIRFIELDS...BUT
BEST CHANCES APPEAR AT KAVL/KHKY AND KGMU WHERE TEMPO TSRA WILL BE
CARRIED THIS AFTERNOON. OTHERWISE VFR CIGS...EXCEPT GUIDANCE
SUGGESTS IFR CIG/VSBY DEVELOPING AT KAVL LATE TONIGHT FOR A FEW
HOURS.
.
OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH
LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE
AREA. ANY RESTRICTIONS WOULD BE CONFINED TO DIURNAL TSTMS AND
MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-21Z
KCLT HIGH 95% HIGH 100% HIGH 100% HIGH 97%
KGSP HIGH 100% HIGH 95% HIGH 80% MED 60%
KAVL HIGH 100% HIGH 93% MED 74% HIGH 87%
KHKY HIGH 100% HIGH 100% HIGH 95% MED 72%
KGMU HIGH 100% HIGH 100% HIGH 95% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 87% MED 72%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JOH
NEAR TERM...LG/NED
SHORT TERM...CDG
LONG TERM...JOH/WIMBERLEY
AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
300 PM EDT WED JUL 9 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL PUSH THROUGH THE AREA TONIGHT AND REMAINS IN
PLACE THURSDAY BEFORE WASHING OUT BY FRIDAY. WEAK HIGH PRESSURE WILL
RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
AT 215PM...MOST THUNDERSTORM COVERAGE AT MID AFTERNOON IS ACROSS THE
SOUTHERN UPSTATE EASTWARD INTO NC. NUMEROUS STORMS DEVELOPED IN A
DIFFERENTIAL HEATING AXIS CREATED BY CLOUD COVER TO NORTH EARLIER
TODAY. PLUS THE LEE TROF HAS PROVIDED SOME LOW LEVEL CONVERGENCE. AN
UPPER SHORT WAVE DEPICTED BY THE RAP IS ALSO CROSSING THE AREA.
SHOULD SEE SOME ADDITIONAL DEVELOPMENT ACROSS THE NC
MOUNTAINS/FOOTHILLS PER CAMS SO WILL CONTINUE WITH SCT TYPE POPS
THOSE AREAS. SHOULD SEE THE COVERAGE OF CONVECTION WANE THIS EVENING
AS S/W MOVES TO THE E. HOWEVER...A COLD FRONT JUST WEST OF THE
APPALACHIANS IS FORECAST TO MOVE INTO THE NC MOUNTAINS THIS EVENING
WHICH COULD KICK OFF SOME ADDITIONAL SHOWERS/THUNDERSTORMS...SO WILL
SHOW AN UPTICK IN POPS OVER THE WEST THIS EVENING AGAIN. THE 12Z GFS
SEEMS TO HAVE SOME CONVECTIVE FEEDBACK OVER FAR WESTERN NC IN THE
00Z-06Z TIMEFRAME AND WILL NOT BUY INTO THE HIGH GFS QPF DEPICTED
THERE.
ON THU...THE FRONT IS FORECAST TO REACH THE PIEDMONT. THE MODELS
DEPICT A WEAK WAVE DEVELOPING ON THE BOUNDARY WHICH SHOULD TEND TO
ENHANCE THE COVERAGE NEAR IT. PLUS...ANOTHER WEAK SHORT WAVE IS
FORECAST TO CROSS THE AREA. HENCE...WILL STAY WITH THE IDEA OF
SCT-NUMEROUS SHOWERS/STORMS ACROSS THE PIEDMONT DURING THE
AFTERNOON...WITH LOWER POPS TO THE NORTH. SOUNDINGS LOOK MORE
SATURATED WITH LESS DCAPE...SO DO NOT EXPECT MUCH IN THE WAY OF A
SEVERE THREAT. MAX TEMPS ARE FORECAST TO BE ABOUT A CATEGORY BELOW
CLIMO.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 100 PM WEDNESDAY...THE SHORT TERM PERIOD INITIALIZES THURSDAY
EVENING WITH A QUASI STATIONARY FRONTAL BOUNDARY POSITIONED JUST
SOUTH OF INTERSTATE 85 INTO THE MIDLANDS OF SC...STRETCHING
NORTHEASTWARD INTO CENTRAL NC. SCATTERED CONVECTION WILL LIKELY BE
ONGOING AS HEATING WILL HAVE STEEPENED LAPSE RATES IN PROXIMITY TO
THE SURFACE BOUNDARY...WHICH WILL PROVIDE A FOCUS FOR SAID
CONVECTION. MEANWHILE...POSITIVELY TILTED UPPER TROF WILL BE
LIFTING TO THE NORTHEAST ALLOWING H5 HEIGHTS TO RISE. POPS WILL
TAPER DOWN DUE TO RISING HEIGHTS ALOFT AND HEATING LOSS INTO THE
OVERNIGHT HOURS OF FRIDAY MORNING. LATEST GUIDANCE INDICATES
POTENTIAL WEAK MESOLOW DEVELOPMENT ALONG THE FL PANHANDLE ON FRIDAY
MORNING ALLOWING FOR ENHANCED SOUTHEASTERLY FLOW INTO THE
CAROLINAS. THIS COMBINED WITH FLOW AROUND THE WESTERN ATLANTIC
SURFACE RIDGE WILL ALLOW THE STALLED FRONTAL BOUNDARY TO GRADUALLY
LIFT NORTHWARD TOWARDS THE CWFA INTO THE LATE AFTERNOON HOURS.
MOISTURE CONVERGENCE ALONG THIS BOUNDARY WILL PROVIDE A FOCUS FOR
CONVECTION ACROSS THE NC/SC PIEDMONT WHERE STEEPENING LAPSE RATES
AND INCREASED MOISTURE YIELD SBCAPE VALUES IN EXCESS OF 1500J/KG.
THUS WILL FAVOR LOW END CHANCE LEVEL POPS ACROSS THE PIEDMONT...AND
ALSO ALONG THE HIGH TERRAIN WHERE EAST SOUTHEAST UPSLOPE FLOW AIDS
CONVECTION. SLIGHT CHANCE POPS WILL OVERSPREAD THE REMAINDER OF THE
FORECAST AREA BEFORE DIURNAL COOLING WARRANTS TAPERED POPS ACROSS
THE ENTIRE REGION FOR THE OVERNIGHT.
SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE NORTHEAST
INTO THE WEEKEND...AND WILL EXTEND SOUTHWARD INTO THE
SOUTHERN/CENTRAL APPS. THIS COMBINED WITH RISING HEIGHTS ALOFT
WILL LIMIT CONVECTION EARLY ON SATURDAY BEFORE WEAK CIN IS OVERCOME
BY HEATING. EXPECTING INITIATION TO OCCUR ACROSS THE HIGH TERRAIN
ON SATURDAY AFTERNOON BEFORE WEAK NW FLOW ALOFT PROPAGATES SHOWERS
AND THUNDERSTORMS SOUTHEAST INTO THE FOOTHILLS/PIEDMONT REGIONS OF
NC/SC. DIURNALLY FAVORED LOW/MID LEVEL CHANCE POPS WILL HIGHLIGHT
THE FORECAST FOR SATURDAY. TEMPERATURES THROUGH THE SHORT TERM
PERIOD WILL BE AT OR JUST SLIGHTLY BELOW CLIMO.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF 245 PM EDT TUE...THE LATEST GLOBAL MODELS CONTINUE TO INDICATE
THAT UPPER H5 HEIGHTS WILL FALL ACROSS THE SOUTHEAST SAT NIGHT INTO
SUN AS AN UPPER RIDGE OF HIGH AMPLIFIES OVER THE WESTERN CONUS WHILE
AN UPPER LOW PRESSURE TROUGH APPROACHES THE GREAT LAKES REGION FROM
SOUTH CENTRAL CANADA. THIS TROUGH IS EXPECTED TO SWING ACROSS THE
EASTERN STATES MON THROUGH WED.
AT THE SURFACE...BERMUDA HIGH WILL PERSIST THROUGH SUN BEFORE
SHIFTING TO THE EAST BY EARLY MON AS A COLD FRONT APPROACHES FROM
THE NW. THE FRONT IS EXPECTED TO CROSS THE AREA THROUGH MON NIGHT
FOLLOWED BY ANOTHER FRONT ON TUE. THE FRONT WILL REMAIN SOUTH OF THE
AREA WED AS A CONTINENTAL HIGH BUILDS IN FROM THE NW. AS FOR OUR
SENSIBLE WEATHER...POPS REMAIN NEAR CLIMO EACH DAY GIVEN LITTLE TO
NO CAPPING ALOFT AND SEASONABLY UNSTABLE AIRMASS DURING THE PEAK
HEATING HOURS. TEMPERATES WILL REMAIN NEAR...OR A FEW DEGREES BELOW
NORMAL THROUGH THE PERIOD.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
A CLT...MAIN CONCERN AS USUAL THIS TIME OF YEAR IS WHEN AND IF THE
AIRFIELD WILL SEE THUNDER. MOST CONVECTION AT THE MOMENT REMAINS SOUTH
OF THE AIRPORT. HOWEVER...MOST MESO MODELS BLOW UP CONVECTION OVER
CLT IN THE 20Z-00Z TIMEFRAME. HENCE...WILL CARRY A TEMPO FOR TSRA
DURING THAT TIME ALONG WITH RESTRICTIONS. CONVECTION SHOULD WANE
THIS EVENING LEAVING JUST VFR TYPE CEILINGS.
ELSEWHERE...THUNDERSTORMS COULD AFFECT ANY OF THE AIRFIELDS...BUT
BEST CHANCES APPEAR AT KAVL/KHKY AND KGMU WHERE TEMPO TSRA WILL BE
CARRIED THIS AFTERNOON. OTHERWISE VFR CIGS...EXCEPT GUIDANCE
SUGGESTS IFR CIG/VSBY DEVELOPING AT KAVL LATE TONIGHT FOR A FEW
HOURS.
.
OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH
LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE
AREA. ANY RESTRICTIONS WOULD BE CONFINED TO DIURNAL TSTMS AND
MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-19Z
KCLT HIGH 88% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 80% MED 65%
KAVL HIGH 100% HIGH 93% HIGH 83% HIGH 86%
KHKY HIGH 100% HIGH 100% HIGH 97% HIGH 80%
KGMU HIGH 100% HIGH 100% HIGH 97% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 88% MED 76%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JOH
NEAR TERM...LG
SHORT TERM...CDG
LONG TERM...JOH/WIMBERLEY
AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
104 PM EDT WED JUL 9 2014
.SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP TODAY IN
THE MOIST AIR MASS AHEAD OF A COLD FRONT ENTERING THE REGION. THAT
FRONT WILL STALL OVER THE AREA TONIGHT AND ENHANCE PRECIPITATION
CHANCES THURSDAY BEFORE WEAKENING FRIDAY. WEAK HIGH PRESSURE WILL
RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AT 1215PM...RADAR RETURNS INCREASING TO THE SOUTH AND WEST AND
EXPECT THAT AS A WEAK S/W TRAVERSES THE AREA THAT COVERAGE OF
SHOWERS/STORMS WILL CONTINUE TO INCREASE. SBCAPES HAVE INCREASED TO
OVER 2000J/KG OVER A LARGE PORTION OF THE UPSTATE AND CLT METRO
AREA. SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER THE SOUTHERN
UPSTATE APPARENTLY IN AN AREA OF DIFFERENTIAL HEATING CAUSED BY
CLOUDS TO THE N. HAVE UPDTATED POPS TO REFLECT THIS ACTIVITY.
AS OF 1015 AM...NOT MANY ECHOES ON RADAR AT MID MORNING.
HOWEVER...CAMS, 12Z NAM AND RAP ALL INDCIATE THAT COVERAGE WILL
INCREASE THIS AFTERNOON AS ATMOSPHERE DESTABLIZES WITH AFTERNOON
HEATING. RAP INDICATES A WEAK SHORT WAVE OVER EASTERN TN WHICH MOVES
THROUGH THE WESTERN CAROLINAS AND NE GA BY 00Z. THIS SHOULD
PROVIDE JUST ENOUGH UPPER FORCING TO PRODUCE SCT TO EVEN NUMEROUS
SHOWERS/THUNDERSTORMS. OUR LOCAL CAMPOP GUIDANCE SHOWS THE BEST
COVERAGE NORTH OF I-85 THIS AFTERNOON WITH THE ACTUAL HIGHEST POPS
OVER THE NC FOOTHILLS/NC PIEDMONT. HAVE ADJUSTED THE POP GRIDS TO
DEPICT THAT GENERAL SCENARIO BY BLENDING CAMPOP/CONSSHORT. CAN`T
RULE OUT A FEW STORMS THAT WILL PRODUCE SOME GUSTY WINDS/HAIL...BUT
THE OVERALL SEVERE THREAT IS ON THE LOW SIDE AS SHEAR IS
UNIMPRESSIVE. BLENDED IN THE LATEST CONSHORT DATA TO ADJUST
TEMPS/DEWPOINTS WINDS. THIS GENERALLY LOWERED MAX TEMPS BY A DEGREE
OR TWO DUE TO A BIT MORE CLOUDINESS.
PREVIOUS DISCUSSION:
THERE IS VERY LITTLE ONGOING CONVECTIVE ACTIVITY IN OR IMMEDIATELY
UPSTREAM OF THE CWA...NOT SURPRISING CONSIDERING THAT THE AREA IS
WITHIN AN INSTABILITY MINIMUM. NEVERTHELESS...THERE IS STILL SOME
WEAK BUOYANCY UPSTREAM OVER THE TENN VALLEY...AND LATEST KGSP VAD
WIND PROFILE IS CONFIRMING A STOUT 25 TO 35 KTS OF WESTERLY FLOW
ABOVE ABOUT 2 KFT. IN ADDITION...SCATTERED SHOWERS WERE DEVELOPING
AT 07Z ALONG THE WINDWARD SIDE OF THE CUMBERLAND PLATEAU...WHICH
WOULD PROBABLY ARRIVE IN THE FAR WESTERN NC MTNS BY THE START OF THE
PERIOD. WE WILL CONTINUE TO RAMP POPS UP TO HIGH CHANCE ACROSS THE
TENN BORDER COUNTIES BY SUNRISE.
OTHERWISE...THE CONVECTIVE SETUP FOR LATER TODAY LEAVES MUCH TO BE
DESIRED. THE FRONTAL ZONE...SUCH AS IT IS...IS STILL DRAPED FROM THE
OHIO VALLEY W/SW TOWARD THE ARKLATEX. IN OTHER WORDS...IT HAS A LONG
WAY TO GO TO BE A PLAYER IN CONVECTIVE CHANCES ACROSS OUR AREA THIS
AFTERNOON. IN FACT...IT MAY TURN OUT THAT THE MAIN FOCUS (OTHER THAN
THE USUAL TERRAIN/DIFFERENTIAL HEATING EFFECTS) MAY BE A LEE SIDE
TROUGH...BUT EVEN THAT MAY BE MORE OF A CONCERN FOR AREAS JUST TO
OUR EAST. ADDITIONALLY...THERE IS A FAIRLY STRONG SIGNAL IN THE
LATEST MODEL GUIDANCE...AND IN OBSERVATIONAL TRENDS...THAT PESKY
MID/HIGH LEVEL CLOUDS WILL HINDER DIURNAL DESTABILIZATION. IN
FACT...FOR THIS VERY REASON THE MAX TEMP FORECAST IS 2-4 DEGREES
LOWER THAN WHAT WE HAVE SEEN THE PAST COUPLE OF DAYS. FINALLY...
WHILE PROFILES WILL BE MOISTENING CONSIDERABLY...FORECAST PWATS ARE
ONLY 1-2 STANDARD DEVIATIONS ABOVE CLIMO. ALL THINGS CONSIDERED...
HAVE ESSENTIALLY OPTED FOR A SHOTGUNNED 40-50 POPS ACROSS THE CWA...
WITH A SMALL AREA OF LIKELY ACROSS THE SOUTHWEST MTNS...WHICH WILL
HAVE THE BENEFIT OF A CONTINUED (ALBEIT WEAKENING) W/SW UPSLOPE
FLOW. IN TERMS OF THE SEVERE THREAT...MODEST INSTABILITY/MOIST
PROFILES AND WEAKENING SHEAR SHOULD LIMIT THE POTENTIAL
CONSIDERABLY. HOWEVER...THE PIEDMONT WILL HAVE TO BE WATCHED
CLOSELY...ESPECIALLY IF INSOLATION/HEATING IS MORE SIGNIFICANT THAN
EXPECTED.
THE FRONTAL ZONE WILL FINALLY SETTLE INTO THE AREA TONIGHT...BUT BY
THAT TIME...WITH WIND PROFILES WEAKENING AND MODEST AT BEST
NOCTURNAL INSTABILITY...SUSPECT IT WILL BE DIFFICULT TO GET MUCH
MORE THAN SCATTERED CONVECTION FOR TOO LONG PAST MID-EVENING OR SO.
MIN TEMPS WILL REMAIN ABOVE CLIMO UNDER CONSIDERABLE CLOUD
COVER.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 100 PM WEDNESDAY...THE SHORT TERM PERIOD INITIALIZES THURSDAY
EVENING WITH A QUASI STATIONARY FRONTAL BOUNDARY POSITIONED JUST
SOUTH OF INTERSTATE 85 INTO THE MIDLANDS OF SC...NORTHEASTWARD INTO
CENTRAL NC. SCATTERED CONVECTION WILL LIKELY BE ONGOING AS HEATING
WILL HAVE STEEPENED LAPSE RATES IN PROXIMITY TO THE SURFACE
BOUNDARY...WHICH WILL PROVIDE A FOCUS FOR SAID CONVECTION.
MEANWHILE...POSITIVELY TILTED UPPER TROF WILL BE LIFTING TO THE
NORTHEAST ALLOWING HEIGHTS TO RISE WITH POPS TAPERING DOWN INTO
FRIDAY MORNING. LATEST GUIDANCE INDICATES WEAK MESOLOW DEVELOPMENT
ALONG THE FL PANHANDLE ON FRIDAY MORNING ALLOWING FOR ENHANCED
SOUTHEASTERLY FLOW INTO THE CAROLINAS. THIS COMBINED WITH FLOW
AROUND THE WESTERN ATLANTIC SURFACE RIDGE WILL ALLOW THE STALLED
FRONTAL BOUNDARY TO GRADUALLY LIFT NORTHWARD TOWARDS THE SOUTHERN
APPS INTO THE LATE AFTERNOON HOURS. MOISTURE CONVERGENCE ALONG THIS
BOUNDARY WILL PROVIDE A FOCUS FOR CONVECTION ACROSS THE NC/SC
PIEDMONT ON FRIDAY AFTERNOON WHERE STEEPENING LAPSE RATES AND
INCREASED MOISTURE YIELD SBCAPE VALUES IN EXCESS OF 1500J/KG. THUS
WILL FAVOR LOW END CHANCE LEVEL POPS ACROSS THE PIEDMONT...AND ALSO
ALONG THE HIGH TERRAIN WHERE EAST SOUTHEAST UPSLOPE FLOW AIDS
CONVECTION. SLIGHT CHANCE POPS WILL OVERSPREAD THE REMAINDER OF THE
FORECAST AREA.
SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE NORTHEAST
INTO THE WEEKEND...AND WILL EXTEND SOUTHWARD INTO THE
SOUTHERN/CENTRAL APPS. THIS COMBINED WITH RISING HEIGHTS ALOFT
WILL LIMIT CONVECTION EARLY ON SATURDAY BEFORE WEAK CIN IS OVERCOME
BY HEATING. EXPECTING INITIATION TO OCCUR ACROSS THE HIGH TERRAIN
ON SATURDAY AFTERNOON BEFORE WEAK NW FLOW ALOFT PROPAGATES SHOWERS
AND THUNDERSTORMS SOUTHEAST INTO THE FOOTHILLS/PIEDMONT REGIONS OF
NC/SC. DIURNALLY FAVORED LOW/MID LEVEL CHANCE POPS WILL HIGHLIGHT
THE FORECAST FOR SATURDAY. TEMPERATURES THROUGH THE SHORT TERM
PERIOD WILL BE AT OR JUST SLIGHTLY BELOW CLIMO.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 300 AM TUE...WHILE SOME VESTIGE OF A FRONTAL BOUNDARY MAY
REMAIN OVER THE COASTAL PLAIN THIS WEEKEND...THE PATTERN ACRS THE
REGION WILL BE DOMINATED BY BERMUDA HIGH AT THE SFC. THAT WILL
MAINTAIN LIGHT SOUTHERLY FLOW INTO THE FA...BUT INSTEAD OF KEEPING
US CAPPED THRU SUBSIDENCE...BROADLY CYCLONIC UPPER FLOW ABOVE IT
WILL KEEP CONDITIONS MODESTLY FAVORABLE FOR DIURNAL CONVECTION. THIS
IS THE PREVAILING SIGNAL FOR POPS DURING THE PERIOD. TEMPS WILL
TREND FROM SLIGHTLY BELOW NORMAL SATURDAY TO SLIGHTLY ABOVE NORMAL
BY TUESDAY.
A FRONT WILL DIVE THRU THE NRN PLAINS OVER THE WEEKEND AS TROUGH DIGS
ACRS ERN CANADA. A WEAK LEADING FRONT WILL PUSH THRU THE OH/TN
VALLEYS AND INTO THE AREA MONDAY...ENHANCING PRECIP COVERAGE. THE
TROUGH AMPLIFIES FURTHER IN THE MIDDLE OF THE WEEK WHICH BRINGS THE
STRONGER FRONT SWD TOWARD US. CURRENT GUIDANCE PUTS THIS ON WED
BEYOND THE END OF THE FCST.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT AND ELSEWHERE (EXCEPT KAVL)...CANNOT RULE OUT A FEW SHOWERS
POPPING UP OR MOVING OUT OF THE MTNS AT JUST ABOUT ANYTIME THIS
MORNING...BUT COVERAGE SHOULD BE VERY SPARSE UNTIL AFTERNOON.
OTHERWISE...PREVAILING VFR CONDITIONS ARE EXPECTED (OUTSIDE OF
SHOWERS/TSTORMS) THROUGH THE PERIOD. COVERAGE OF CONVECTION IS
EXPECTED TO INCREASE THIS AFTERNOON...BUT THERE IS STILL SOME
UNCERTAINTY AS TO THE DEGREE OR COVERAGE. OUR BEST EDUCATED GUESS
CONTINUES TO INDICATE COVERAGE SHOULD REMAIN SCATTERED...AND ALL
TAFS SEE A PROB30 DURING THE AFTERNOON THROUGH MID EVENING OR SO.
AT KAVL...OTHER THAN PERHAPS A STRAY SHOWER OR TWO DEVELOPING NEAR
THE TENN BORDER AND PASSING NEAR THE TERMINAL THIS MORNING...THE
BULK OF CONVECTIVE ACTIVITY SHOULD HOLD OFF UNTIL AFTERNOON...WHEN A
TEMPO IS BEING CARRIED BETWEEN 18Z AND 22Z...ALTHOUGH CONVECTIVE
CHANCES WILL CONTINUE INTO THE EVENING. WE ARE STILL WAITING FOR A
FOGGY NIGHT TO OCCUR AT KAVL...AND WHILE IT IS UNCLEAR THAT TONIGHT
WILL BE THE NIGHT...BASED UPON A CONSENSUS OF GUIDANCE...MVFR VISBY
HAS BEEN INTRODUCED TOWARD DAYBREAK.
OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH
LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE
AREA. ANY RESTRICTIONS WOULD BE CONFINED TO DIURNAL TSTMS AND
MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-17Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 95%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% MED 71% HIGH 83%
KHKY HIGH 100% HIGH 100% HIGH 91% HIGH 90%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 90%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...WIMBERLEY
NEAR TERM...LG
SHORT TERM...WIMBERLEY
LONG TERM...WIMBERLEY
AVIATION...JDL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1207 PM EDT WED JUL 9 2014
.SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP TODAY IN
THE MOIST AIR MASS AHEAD OF A COLD FRONT ENTERING THE REGION. THAT
FRONT WILL STALL OVER THE AREA TONIGHT AND ENHANCE PRECIPITATION
CHANCES THURSDAY BEFORE WEAKENING FRIDAY. WEAK HIGH PRESSURE WILL
RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AT 1205PM...NOT MUCH CHANGE IN THINKING FOR THIS UPDATE. RADAR
RETURNS INCREASING TO THE WEST AND EXPECT THAT AS A WEAK S/W
TRAVERSES THE AREA THAT COVERAGE OF SHOWERS/STORMS WILL INCREASE.
SBCAPES HAVE INCREASED TO OVER 2000J/KG OVER A LARGE PORTION OF
THE UPSTATE AND CLT METRO AREA. HOWEVER....STILL SOME LOW LEVEL
CIN INHIBITING CONVECTION SO IT WILL BE COUPLE MORE HOURS BEFORE
DEEP CONVECTION CAN GET GOING. MADE SOME MINOR ADJUSTMENTS TO GRID
FIELDS BASED ON LATEST CONSSHORT DATA...BUT NO CHANGES TO POP
TRENDS.
AS OF 1015 AM...NOT MANY ECHOES ON RADAR AT MID MORNING.
HOWEVER...CAMS, 12Z NAM AND RAP ALL INDCIATE THAT COVERAGE WILL
INCREASE THIS AFTERNOON AS ATMOSPHERE DESTABLIZES WITH AFTERNOON
HEATING. RAP INDICATES A WEAK SHORT WAVE OVER EASTERN TN WHICH MOVES
THROUGH THE WESTERN CAROLINAS AND NE GA BY 00Z. THIS SHOULD
PROVIDE JUST ENOUGH UPPER FORCING TO PRODUCE SCT TO EVEN NUMEROUS
SHOWERS/THUNDERSTORMS. OUR LOCAL CAMPOP GUIDANCE SHOWS THE BEST
COVERAGE NORTH OF I-85 THIS AFTERNOON WITH THE ACTUAL HIGHEST POPS
OVER THE NC FOOTHILLS/NC PIEDMONT. HAVE ADJUSTED THE POP GRIDS TO
DEPICT THAT GENERAL SCENARIO BY BLENDING CAMPOP/CONSSHORT. CAN`T
RULE OUT A FEW STORMS THAT WILL PRODUCE SOME GUSTY WINDS/HAIL...BUT
THE OVERALL SEVERE THREAT IS ON THE LOW SIDE AS SHEAR IS
UNIMPRESSIVE. BLENDED IN THE LATEST CONSHORT DATA TO ADJUST
TEMPS/DEWPOINTS WINDS. THIS GENERALLY LOWERED MAX TEMPS BY A DEGREE
OR TWO DUE TO A BIT MORE CLOUDINESS.
PREVIOUS DISCUSSION:
THERE IS VERY LITTLE ONGOING CONVECTIVE ACTIVITY IN OR IMMEDIATELY
UPSTREAM OF THE CWA...NOT SURPRISING CONSIDERING THAT THE AREA IS
WITHIN AN INSTABILITY MINIMUM. NEVERTHELESS...THERE IS STILL SOME
WEAK BUOYANCY UPSTREAM OVER THE TENN VALLEY...AND LATEST KGSP VAD
WIND PROFILE IS CONFIRMING A STOUT 25 TO 35 KTS OF WESTERLY FLOW
ABOVE ABOUT 2 KFT. IN ADDITION...SCATTERED SHOWERS WERE DEVELOPING
AT 07Z ALONG THE WINDWARD SIDE OF THE CUMBERLAND PLATEAU...WHICH
WOULD PROBABLY ARRIVE IN THE FAR WESTERN NC MTNS BY THE START OF THE
PERIOD. WE WILL CONTINUE TO RAMP POPS UP TO HIGH CHANCE ACROSS THE
TENN BORDER COUNTIES BY SUNRISE.
OTHERWISE...THE CONVECTIVE SETUP FOR LATER TODAY LEAVES MUCH TO BE
DESIRED. THE FRONTAL ZONE...SUCH AS IT IS...IS STILL DRAPED FROM THE
OHIO VALLEY W/SW TOWARD THE ARKLATEX. IN OTHER WORDS...IT HAS A LONG
WAY TO GO TO BE A PLAYER IN CONVECTIVE CHANCES ACROSS OUR AREA THIS
AFTERNOON. IN FACT...IT MAY TURN OUT THAT THE MAIN FOCUS (OTHER THAN
THE USUAL TERRAIN/DIFFERENTIAL HEATING EFFECTS) MAY BE A LEE SIDE
TROUGH...BUT EVEN THAT MAY BE MORE OF A CONCERN FOR AREAS JUST TO
OUR EAST. ADDITIONALLY...THERE IS A FAIRLY STRONG SIGNAL IN THE
LATEST MODEL GUIDANCE...AND IN OBSERVATIONAL TRENDS...THAT PESKY
MID/HIGH LEVEL CLOUDS WILL HINDER DIURNAL DESTABILIZATION. IN
FACT...FOR THIS VERY REASON THE MAX TEMP FORECAST IS 2-4 DEGREES
LOWER THAN WHAT WE HAVE SEEN THE PAST COUPLE OF DAYS. FINALLY...
WHILE PROFILES WILL BE MOISTENING CONSIDERABLY...FORECAST PWATS ARE
ONLY 1-2 STANDARD DEVIATIONS ABOVE CLIMO. ALL THINGS CONSIDERED...
HAVE ESSENTIALLY OPTED FOR A SHOTGUNNED 40-50 POPS ACROSS THE CWA...
WITH A SMALL AREA OF LIKELY ACROSS THE SOUTHWEST MTNS...WHICH WILL
HAVE THE BENEFIT OF A CONTINUED (ALBEIT WEAKENING) W/SW UPSLOPE
FLOW. IN TERMS OF THE SEVERE THREAT...MODEST INSTABILITY/MOIST
PROFILES AND WEAKENING SHEAR SHOULD LIMIT THE POTENTIAL
CONSIDERABLY. HOWEVER...THE PIEDMONT WILL HAVE TO BE WATCHED
CLOSELY...ESPECIALLY IF INSOLATION/HEATING IS MORE SIGNIFICANT THAN
EXPECTED.
THE FRONTAL ZONE WILL FINALLY SETTLE INTO THE AREA TONIGHT...BUT BY
THAT TIME...WITH WIND PROFILES WEAKENING AND MODEST AT BEST
NOCTURNAL INSTABILITY...SUSPECT IT WILL BE DIFFICULT TO GET MUCH
MORE THAN SCATTERED CONVECTION FOR TOO LONG PAST MID-EVENING OR SO.
MIN TEMPS WILL REMAIN ABOVE CLIMO UNDER CONSIDERABLE CLOUD
COVER.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 200 AM WED...SFC FRONT WILL SLOWLY MOVE SEWD THRU THE DEEP
SOUTH AND THE CAROLINAS FROM THURSDAY INTO EARLY SATURDAY...WHILE
BROAD HIGH PRESSURE BUILDS TOWARD THE EAST COAST AS HEIGHTS RISE
ALOFT. DEEP THICKNESSES DO NOT DROP APPRECIABLY BEHIND THE
FRONT...AND IN SOMEWHAT OF A DEPARTURE FROM PREVIOUS RUNS...LATEST
MODEL SOLUTIONS APPEAR TO WEAKEN THE FRONT AND VIRTUALLY WASH IT OUT
OVER THE PIEDMONT INSTEAD OF PUSHING IT OFF TO THE COAST AS BEFORE.
HOWEVER THIS DIFFERENCE DOES NOT IMPLY MAJOR CHANGES TO THE FCST
TRENDS SINCE THE FRONT SHOULD MAINLY JUST SERVE TO FOCUS DIURNAL
CONVECTION ACRS THE AREA. WILL CONTINUE TO ADVERTISE HIGH CHANCE POPS
THU...BUT WILL KEEP A SCHC OVER MOST AREAS THRU THU NIGHT. WHATEVER
WEAK LLVL FORCING PERSISTS LOOKS UNLIKELY TO FIRE MUCH
CONVECTION...BUT THE MERE PRESENCE OF THE BOUNDARY AND MODEST LAPSE
RATES WARRANT A LOW POP MENTION. BY FRIDAY MODEL QPF RESPONSE FAVORS
THE SC MIDLANDS AND CENTRAL NC. MOSTLY SCHC POPS ARE ADVERTISED...BUT
THESE TOO ARE SLOW TO DIMINISH FRI NIGHT.
CONSENSUS OF NAM/SREF INDICATES CAPE VALUES EACH AFTERNOON WILL BE
TYPICAL FOR THE SEASON...1000-2000 J/KG...THOUGH THE GFS IS MORE
STABLE FRIDAY WITH MORE OF THE REGION ON THE COOL SIDE OF THE FRONT.
H5 WINDS AND SHEAR PROFILES ARE UNIMPRESSIVE...AND PWAT VALUES REMAIN
NEAR CLIMO. SEVERE THREAT WITH CELLS WILL BE NONZERO BUT NOT
PARTICULARLY NOTABLE...THOUGH LOCALLY HEAVY RAIN IS LIKELY THURSDAY
BEFORE DRIER AIR MOVES IN ALOFT. TEMPS WILL REMAIN JUST BELOW NORMAL.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 AM TUE...WHILE SOME VESTIGE OF A FRONTAL BOUNDARY MAY
REMAIN OVER THE COASTAL PLAIN THIS WEEKEND...THE PATTERN ACRS THE
REGION WILL BE DOMINATED BY BERMUDA HIGH AT THE SFC. THAT WILL
MAINTAIN LIGHT SOUTHERLY FLOW INTO THE FA...BUT INSTEAD OF KEEPING
US CAPPED THRU SUBSIDENCE...BROADLY CYCLONIC UPPER FLOW ABOVE IT
WILL KEEP CONDITIONS MODESTLY FAVORABLE FOR DIURNAL CONVECTION. THIS
IS THE PREVAILING SIGNAL FOR POPS DURING THE PERIOD. TEMPS WILL
TREND FROM SLIGHTLY BELOW NORMAL SATURDAY TO SLIGHTLY ABOVE NORMAL
BY TUESDAY.
A FRONT WILL DIVE THRU THE NRN PLAINS OVER THE WEEKEND AS TROUGH DIGS
ACRS ERN CANADA. A WEAK LEADING FRONT WILL PUSH THRU THE OH/TN
VALLEYS AND INTO THE AREA MONDAY...ENHANCING PRECIP COVERAGE. THE
TROUGH AMPLIFIES FURTHER IN THE MIDDLE OF THE WEEK WHICH BRINGS THE
STRONGER FRONT SWD TOWARD US. CURRENT GUIDANCE PUTS THIS ON WED
BEYOND THE END OF THE FCST.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT AND ELSEWHERE (EXCEPT KAVL)...CANNOT RULE OUT A FEW SHOWERS
POPPING UP OR MOVING OUT OF THE MTNS AT JUST ABOUT ANYTIME THIS
MORNING...BUT COVERAGE SHOULD BE VERY SPARSE UNTIL AFTERNOON.
OTHERWISE...PREVAILING VFR CONDITIONS ARE EXPECTED (OUTSIDE OF
SHOWERS/TSTORMS) THROUGH THE PERIOD. COVERAGE OF CONVECTION IS
EXPECTED TO INCREASE THIS AFTERNOON...BUT THERE IS STILL SOME
UNCERTAINTY AS TO THE DEGREE OR COVERAGE. OUR BEST EDUCATED GUESS
CONTINUES TO INDICATE COVERAGE SHOULD REMAIN SCATTERED...AND ALL
TAFS SEE A PROB30 DURING THE AFTERNOON THROUGH MID EVENING OR SO.
AT KAVL...OTHER THAN PERHAPS A STRAY SHOWER OR TWO DEVELOPING NEAR
THE TENN BORDER AND PASSING NEAR THE TERMINAL THIS MORNING...THE
BULK OF CONVECTIVE ACTIVITY SHOULD HOLD OFF UNTIL AFTERNOON...WHEN A
TEMPO IS BEING CARRIED BETWEEN 18Z AND 22Z...ALTHOUGH CONVECTIVE
CHANCES WILL CONTINUE INTO THE EVENING. WE ARE STILL WAITING FOR A
FOGGY NIGHT TO OCCUR AT KAVL...AND WHILE IT IS UNCLEAR THAT TONIGHT
WILL BE THE NIGHT...BASED UPON A CONSENSUS OF GUIDANCE...MVFR VISBY
HAS BEEN INTRODUCED TOWARD DAYBREAK.
OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH
LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE
AREA. ANY RESTRICTIONS WOULD BE CONFINED TO DIURNAL TSTMS AND
MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
16-22Z 22-04Z 04-10Z 10-16Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 80% HIGH 80%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 87%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 87%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...WIMBERLEY
NEAR TERM...LG
SHORT TERM...WIMBERLEY
LONG TERM...WIMBERLEY
AVIATION...JDL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1032 AM EDT WED JUL 9 2014
.SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP TODAY IN
THE MOIST AIR MASS AHEAD OF A COLD FRONT ENTERING THE REGION. THAT
FRONT WILL STALL OVER THE AREA TONIGHT AND ENHANCE PRECIPITATION
CHANCES THURSDAY BEFORE WEAKENING FRIDAY. WEAK HIGH PRESSURE WILL
RETURN THROUGH THE WEEKEND BEFORE ANOTHER COLD FRONT APPROACHES THE
AREA EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM...NOT MANY ECHOES ON RADAR AT MID MORNING.
HOWEVER...CAMS, 12Z NAM AND RAP ALL INDCIATE THAT COVERAGE WILL
INCREASE THIS AFTERNOON AS ATMOSPHERE DESTABLIZES WITH AFTERNOON
HEATING. RAP INDICATES A WEAK SHORT WAVE OVER EASTERN TN WHICH MOVES
THROUGH THE WESTERN CAROLINAS AND NE GA BY 00Z. THIS SHOULD
PROVIDE JUST ENOUGH UPPER FORCING TO PRODUCE SCT TO EVEN NUMEROUS
SHOWERS/THUNDERSTORMS. OUR LOCAL CAMPOP GUIDANCE SHOWS THE BEST
COVERAGE NORTH OF I-85 THIS AFTERNOON WITH THE ACTUAL HIGHEST POPS
OVER THE NC FOOTHILLS/NC PIEDMONT. HAVE ADJUSTED THE POP GRIDS TO
DEPICT THAT GENERAL SCENARIO BY BLENDING CAMPOP/CONSSHORT. CAN`T
RULE OUT A FEW STORMS THAT WILL PRODUCE SOME GUSTY
WINDS/HAIL...BUT THE OVERALL SEVERE THREAT IS ON THE LOW SIDE AS
SHEAR IS UNIMPRESSIVE. BLENDED IN THE LATEST CONSHORT DATA TO
ADJUST TEMPS/DEWPOINTS WINDS. THIS GENERALLY LOWERED MAX TEMPS BY
A DEGREE OR TWO DUE TO A BIT MORE CLOUDINESS.
PREVIOUS DISCUSSION:
THERE IS VERY LITTLE ONGOING CONVECTIVE ACTIVITY IN OR IMMEDIATELY
UPSTREAM OF THE CWA...NOT SURPRISING CONSIDERING THAT THE AREA IS
WITHIN AN INSTABILITY MINIMUM. NEVERTHELESS...THERE IS STILL SOME
WEAK BUOYANCY UPSTREAM OVER THE TENN VALLEY...AND LATEST KGSP VAD
WIND PROFILE IS CONFIRMING A STOUT 25 TO 35 KTS OF WESTERLY FLOW
ABOVE ABOUT 2 KFT. IN ADDITION...SCATTERED SHOWERS WERE DEVELOPING
AT 07Z ALONG THE WINDWARD SIDE OF THE CUMBERLAND PLATEAU...WHICH
WOULD PROBABLY ARRIVE IN THE FAR WESTERN NC MTNS BY THE START OF THE
PERIOD. WE WILL CONTINUE TO RAMP POPS UP TO HIGH CHANCE ACROSS THE
TENN BORDER COUNTIES BY SUNRISE.
OTHERWISE...THE CONVECTIVE SETUP FOR LATER TODAY LEAVES MUCH TO BE
DESIRED. THE FRONTAL ZONE...SUCH AS IT IS...IS STILL DRAPED FROM THE
OHIO VALLEY W/SW TOWARD THE ARKLATEX. IN OTHER WORDS...IT HAS A LONG
WAY TO GO TO BE A PLAYER IN CONVECTIVE CHANCES ACROSS OUR AREA THIS
AFTERNOON. IN FACT...IT MAY TURN OUT THAT THE MAIN FOCUS (OTHER THAN
THE USUAL TERRAIN/DIFFERENTIAL HEATING EFFECTS) MAY BE A LEE SIDE
TROUGH...BUT EVEN THAT MAY BE MORE OF A CONCERN FOR AREAS JUST TO
OUR EAST. ADDITIONALLY...THERE IS A FAIRLY STRONG SIGNAL IN THE
LATEST MODEL GUIDANCE...AND IN OBSERVATIONAL TRENDS...THAT PESKY
MID/HIGH LEVEL CLOUDS WILL HINDER DIURNAL DESTABILIZATION. IN
FACT...FOR THIS VERY REASON THE MAX TEMP FORECAST IS 2-4 DEGREES
LOWER THAN WHAT WE HAVE SEEN THE PAST COUPLE OF DAYS. FINALLY...
WHILE PROFILES WILL BE MOISTENING CONSIDERABLY...FORECAST PWATS ARE
ONLY 1-2 STANDARD DEVIATIONS ABOVE CLIMO. ALL THINGS CONSIDERED...
HAVE ESSENTIALLY OPTED FOR A SHOTGUNNED 40-50 POPS ACROSS THE CWA...
WITH A SMALL AREA OF LIKELY ACROSS THE SOUTHWEST MTNS...WHICH WILL
HAVE THE BENEFIT OF A CONTINUED (ALBEIT WEAKENING) W/SW UPSLOPE
FLOW. IN TERMS OF THE SEVERE THREAT...MODEST INSTABILITY/MOIST
PROFILES AND WEAKENING SHEAR SHOULD LIMIT THE POTENTIAL
CONSIDERABLY. HOWEVER...THE PIEDMONT WILL HAVE TO BE WATCHED
CLOSELY...ESPECIALLY IF INSOLATION/HEATING IS MORE SIGNIFICANT THAN
EXPECTED.
THE FRONTAL ZONE WILL FINALLY SETTLE INTO THE AREA TONIGHT...BUT BY
THAT TIME...WITH WIND PROFILES WEAKENING AND MODEST AT BEST
NOCTURNAL INSTABILITY...SUSPECT IT WILL BE DIFFICULT TO GET MUCH
MORE THAN SCATTERED CONVECTION FOR TOO LONG PAST MID-EVENING OR SO.
MIN TEMPS WILL REMAIN ABOVE CLIMO UNDER CONSIDERABLE CLOUD
COVER.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 200 AM WED...SFC FRONT WILL SLOWLY MOVE SEWD THRU THE DEEP
SOUTH AND THE CAROLINAS FROM THURSDAY INTO EARLY SATURDAY...WHILE
BROAD HIGH PRESSURE BUILDS TOWARD THE EAST COAST AS HEIGHTS RISE
ALOFT. DEEP THICKNESSES DO NOT DROP APPRECIABLY BEHIND THE
FRONT...AND IN SOMEWHAT OF A DEPARTURE FROM PREVIOUS RUNS...LATEST
MODEL SOLUTIONS APPEAR TO WEAKEN THE FRONT AND VIRTUALLY WASH IT OUT
OVER THE PIEDMONT INSTEAD OF PUSHING IT OFF TO THE COAST AS BEFORE.
HOWEVER THIS DIFFERENCE DOES NOT IMPLY MAJOR CHANGES TO THE FCST
TRENDS SINCE THE FRONT SHOULD MAINLY JUST SERVE TO FOCUS DIURNAL
CONVECTION ACRS THE AREA. WILL CONTINUE TO ADVERTISE HIGH CHANCE POPS
THU...BUT WILL KEEP A SCHC OVER MOST AREAS THRU THU NIGHT. WHATEVER
WEAK LLVL FORCING PERSISTS LOOKS UNLIKELY TO FIRE MUCH
CONVECTION...BUT THE MERE PRESENCE OF THE BOUNDARY AND MODEST LAPSE
RATES WARRANT A LOW POP MENTION. BY FRIDAY MODEL QPF RESPONSE FAVORS
THE SC MIDLANDS AND CENTRAL NC. MOSTLY SCHC POPS ARE ADVERTISED...BUT
THESE TOO ARE SLOW TO DIMINISH FRI NIGHT.
CONSENSUS OF NAM/SREF INDICATES CAPE VALUES EACH AFTERNOON WILL BE
TYPICAL FOR THE SEASON...1000-2000 J/KG...THOUGH THE GFS IS MORE
STABLE FRIDAY WITH MORE OF THE REGION ON THE COOL SIDE OF THE FRONT.
H5 WINDS AND SHEAR PROFILES ARE UNIMPRESSIVE...AND PWAT VALUES REMAIN
NEAR CLIMO. SEVERE THREAT WITH CELLS WILL BE NONZERO BUT NOT
PARTICULARLY NOTABLE...THOUGH LOCALLY HEAVY RAIN IS LIKELY THURSDAY
BEFORE DRIER AIR MOVES IN ALOFT. TEMPS WILL REMAIN JUST BELOW NORMAL.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 300 AM TUE...WHILE SOME VESTIGE OF A FRONTAL BOUNDARY MAY
REMAIN OVER THE COASTAL PLAIN THIS WEEKEND...THE PATTERN ACRS THE
REGION WILL BE DOMINATED BY BERMUDA HIGH AT THE SFC. THAT WILL
MAINTAIN LIGHT SOUTHERLY FLOW INTO THE FA...BUT INSTEAD OF KEEPING
US CAPPED THRU SUBSIDENCE...BROADLY CYCLONIC UPPER FLOW ABOVE IT
WILL KEEP CONDITIONS MODESTLY FAVORABLE FOR DIURNAL CONVECTION. THIS
IS THE PREVAILING SIGNAL FOR POPS DURING THE PERIOD. TEMPS WILL
TREND FROM SLIGHTLY BELOW NORMAL SATURDAY TO SLIGHTLY ABOVE NORMAL
BY TUESDAY.
A FRONT WILL DIVE THRU THE NRN PLAINS OVER THE WEEKEND AS TROUGH DIGS
ACRS ERN CANADA. A WEAK LEADING FRONT WILL PUSH THRU THE OH/TN
VALLEYS AND INTO THE AREA MONDAY...ENHANCING PRECIP COVERAGE. THE
TROUGH AMPLIFIES FURTHER IN THE MIDDLE OF THE WEEK WHICH BRINGS THE
STRONGER FRONT SWD TOWARD US. CURRENT GUIDANCE PUTS THIS ON WED
BEYOND THE END OF THE FCST.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT AND ELSEWHERE (EXCEPT KAVL)...CANNOT RULE OUT A FEW SHOWERS
POPPING UP OR MOVING OUT OF THE MTNS AT JUST ABOUT ANYTIME THIS
MORNING...BUT COVERAGE SHOULD BE VERY SPARSE UNTIL AFTERNOON.
OTHERWISE...PREVAILING VFR CONDITIONS ARE EXPECTED (OUTSIDE OF
SHOWERS/TSTORMS) THROUGH THE PERIOD. COVERAGE OF CONVECTION IS
EXPECTED TO INCREASE THIS AFTERNOON...BUT THERE IS STILL SOME
UNCERTAINTY AS TO THE DEGREE OR COVERAGE. OUR BEST EDUCATED GUESS
CONTINUES TO INDICATE COVERAGE SHOULD REMAIN SCATTERED...AND ALL
TAFS SEE A PROB30 DURING THE AFTERNOON THROUGH MID EVENING OR SO.
AT KAVL...OTHER THAN PERHAPS A STRAY SHOWER OR TWO DEVELOPING NEAR
THE TENN BORDER AND PASSING NEAR THE TERMINAL THIS MORNING...THE
BULK OF CONVECTIVE ACTIVITY SHOULD HOLD OFF UNTIL AFTERNOON...WHEN A
TEMPO IS BEING CARRIED BETWEEN 18Z AND 22Z...ALTHOUGH CONVECTIVE
CHANCES WILL CONTINUE INTO THE EVENING. WE ARE STILL WAITING FOR A
FOGGY NIGHT TO OCCUR AT KAVL...AND WHILE IT IS UNCLEAR THAT TONIGHT
WILL BE THE NIGHT...BASED UPON A CONSENSUS OF GUIDANCE...MVFR VISBY
HAS BEEN INTRODUCED TOWARD DAYBREAK.
OUTLOOK...SCATTERED MAINLY AFTN THUNDERSTORMS WILL CONTINUE THROUGH
LATE WEEK INTO THE WEEKEND AS HIGH PRESSURE SLOWLY SETTLES OVER THE
AREA. ANY RESTRICTIONS WOULD BE CONFINED TO DIURNAL TSTMS AND
MORNING VALLEY FOG EACH DAY.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-14Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 87% HIGH 86%
KHKY HIGH 100% HIGH 100% HIGH 100% MED 75%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 93%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...WIMBERLEY
NEAR TERM...LG
SHORT TERM...WIMBERLEY
LONG TERM...WIMBERLEY
AVIATION...JDL
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
738 PM CDT THU JUL 10 2014
.UPDATE...
PER WATER VAPOR IMAGERY...IT APPEARS THE MAIN WAVE OF UPPER LEVEL
ENERGY HAS EXITED THE REGION. WHILE THERE MAY BE SOME WEAK
LINGERING ENERGY...ANY ENHANCEMENT OF PRECIPITATION LOOKS LIKE IT
WILL BE CLOSELY TIED TO THE LOW LEVEL JET TONIGHT. MODELS CONTINUE TO
SHOW THE LLJ INCREASING OVER THE EASTERN CWA BETWEEN 03Z-06Z TONIGHT.
THIS AREA REMAINS FAIRLY STABLE DUE TO CLOUD COVER THIS
AFTERNOON...BUT STILL CANNOT RULE OUT A STRONG STORM OR TWO. WILL
MONITOR HEAVY RAIN POTENTIAL AS WELL. THE AREA THAT SAW THE MOST
SUN AND IS MOST UNSTABLE IS OUR FAR SOUTHWEST CWA. PLENTY OF SHEAR
IN THIS REGION AS WELL...SO IF A SEVERE STORM WAS TO GO IT
PROBABLY WOULD BE IN THIS REGION...HOWEVER BEST LOW LEVEL
CONVERGENCE LOOKS TO REMAIN TO THE EAST. WILL CONTINUE TO MONITOR
AND ADJUST POP GRIDS THROUGH THE EVENING.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
SHORT WAVE TROUGH CLOUD COVER AND SCATTERED LIGHT SHOWERS HAVE
LESSENED THE BUILDUP OF INSTABILITY ACROSS THE REGION LATE THIS
AFTERNOON. THE SPC ANALYSIS SHOWED ONLY 500 TO 1500 J/KG OF MIXED
LAYER CAPE FROM NORTH TO SOUTH ACROSS THE CWA LATE THIS AFTERNOON.
ALTHOUGH...THE DEEP LAYER SHEAR WAS IMPRESSIVE UP TO OVER 50
KNOTS. EXPECT SOME MORE BUILDUP OF INSTABILITY INTO THE EVENING
ACROSS THE CWA AS CLOUDS AND LIGHT SHOWERS MOVE EAST. THE GFS AND
HI-RES MODELS STILL SHOWING NUMEROUS SHOWERS/STORMS DEVELOPING
MAINLY ACROSS THE EASTERN CWA THIS EVENING. CENTRAL SD ALSO SEEING
MORE SUNSHINE AND WARMING LATE THIS AFTERNOON. WITH AN INCREASING
85H LLJ ACROSS MAINLY THE EAST THIS EVENING...EXPECT A GOOD CHANCE
OF SHOWERS/STORMS ACROSS THIS REGION. INCREASED POPS THIS EVENING.
THE MODELS THEN SHOW A WEAK BOUNDARY DROPPING SLOWLY SOUTHEAST
TONIGHT AND FRIDAY BRINGING WINDS AROUND TO THE EAST AND NORTHEAST
ACROSS MOST OF THE CWA. AFTER THE CONVECTION TONIGHT...EXPECT MOST
OF FRIDAY TO NOW BE DRY ACROSS THE CWA. THE MODELS THEN SHOW
ANOTHER SHORT WAVE TROUGH FROM THE NORTHWEST DROPPING ACROSS THE
CWA FRIDAY NIGHT AND SATURDAY ALONG WITH A GOOD JET STREAK
DEVELOPING TO OUR NORTH AND NORTHEAST. THIS WILL PUT US IN THE
FAVORABLE RR QUADRANT. THUS...HAVE IN CHANCES OF MAINLY ELEVATED
SHOWERS/STORMS FOR FRIDAY NIGHT AND SATURDAY WITH EVERYTHING
MOVING OFF TO THE SOUTHEAST SATURDAY NIGHT. HIGHS WILL BE IN THE
80S ON FRIDAY AND A FEW DEGREES COOLER ON SATURDAY.
.LONG TERM...SUNDAY THROUGH THURSDAY
SUNDAY SHOULD PROVE TO BE THE WARMEST DAY OF THE EXTENDED
FORECAST PERIOD...WITH ANOMALOUSLY COOL AIR ADVECTING DOWN INTO
THE CWA MONDAY AND STICKING AROUND THROUGH PROBABLY WEDNESDAY...AT
LEAST. THIS SHOULD SPELL SOME MUCH BELOW NORMAL TEMPERATURES
THROUGHOUT THE PERIOD AND DRY CONDITIONS THROUGHOUT THE PERIOD.
COLD AIR INSTABILITY CU/STRATO-CU WILL LIKELY ONLY ADD INSULT TO
INJURY ON MONDAY CLOUDING THINGS UP AND KEEPING JULY INSOLATION
FROM TAKING THE EDGE OFF THE COLDNESS OF THE AIR ON MONDAY.
&&
.CLIMATOLOGICALLY...
AN ANOMALOUSLY COLD LOW PRESSURE SYSTEM WILL MOVE INTO UPPER
MIDWEST EARLY NEXT WEEK. THE COMBINATION OF A COOL CANADIAN
AIRMASS ALONG WITH INCREASING CLOUDS AND A CHANCE FOR SHOWERS
COULD RESULT IN A FEW RECORD LOW HIGH TEMPERATURES ON MONDAY.
BELOW IS A LIST OF LOCATIONS THAT COULD SEE NEAR RECORD COLD
READINGS ON MONDAY:
...LOCATION......FORECAST....RECORD LOW HIGH TEMP...
WHEATON MN 64 72 IN 1949
SISSETON 65 70 IN 1993
WATERTOWN 65 61 IN 1962
ABERDEEN 67 65 IN 1962
MOBRIDGE 69 64 IN 1962
PIERRE 72 65 IN 1989
&&
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
SCATTERED SHOWERS PERSIST ACROSS PARTS OF SOUTH CENTRAL THROUGH
NORTHEAST SOUTH DAKOTA THIS EVENING. AS A LOW LEVEL JET DEVELOPS
LATER IN THE EVENING AN INCREASE IN STORM COVERAGE AND INTENSITY
IS EXPECTED. THE BEST CHANCES FOR THUNDER REMAIN FROM SOUTH
CENTRAL SOUTH DAKOTA THROUGH NORTHEAST SOUTH DAKOTA. WILL MONITOR
SHOWER AND THUNDERSTORM ACTIVITY AND ADJUST TAFS AS NEEDED. BEYOND
REDUCED CIGS/VSBYS UNDER STRONG STORMS...MVFR/IRF CIGS ARE ALSO
LIKELY TO SETTLE IN OVER NORTHEAST SOUTH DAKOTA THROUGH THE
MORNING HOURS. A WEAK COLD FRONT IS THEN EXPECTED TO SLIDE FROM
NORTHWEST TO SOUTHEAST ACROSS THE STATE OF SOUTH DAKOTA ON FRIDAY.
ADDITIONAL SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE
BOUNDARY AND IN CONJUNCTION WITH UPPER LEVEL ENERGY FRIDAY NIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...SERR
SHORT TERM...MOHR
LONG TERM...DORN
AVIATION...SERR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
631 PM CDT THU JUL 10 2014
.UPDATE...
SEE THE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
SHORT WAVE TROUGH CLOUD COVER AND SCATTERED LIGHT SHOWERS HAVE
LESSENED THE BUILDUP OF INSTABILITY ACROSS THE REGION LATE THIS
AFTERNOON. THE SPC ANALYSIS SHOWED ONLY 500 TO 1500 J/KG OF MIXED
LAYER CAPE FROM NORTH TO SOUTH ACROSS THE CWA LATE THIS AFTERNOON.
ALTHOUGH...THE DEEP LAYER SHEAR WAS IMPRESSIVE UP TO OVER 50
KNOTS. EXPECT SOME MORE BUILDUP OF INSTABILITY INTO THE EVENING
ACROSS THE CWA AS CLOUDS AND LIGHT SHOWERS MOVE EAST. THE GFS AND
HI-RES MODELS STILL SHOWING NUMEROUS SHOWERS/STORMS DEVELOPING
MAINLY ACROSS THE EASTERN CWA THIS EVENING. CENTRAL SD ALSO SEEING
MORE SUNSHINE AND WARMING LATE THIS AFTERNOON. WITH AN INCREASING
85H LLJ ACROSS MAINLY THE EAST THIS EVENING...EXPECT A GOOD CHANCE
OF SHOWERS/STORMS ACROSS THIS REGION. INCREASED POPS THIS EVENING.
THE MODELS THEN SHOW A WEAK BOUNDARY DROPPING SLOWLY SOUTHEAST
TONIGHT AND FRIDAY BRINGING WINDS AROUND TO THE EAST AND NORTHEAST
ACROSS MOST OF THE CWA. AFTER THE CONVECTION TONIGHT...EXPECT MOST
OF FRIDAY TO NOW BE DRY ACROSS THE CWA. THE MODELS THEN SHOW
ANOTHER SHORT WAVE TROUGH FROM THE NORTHWEST DROPPING ACROSS THE
CWA FRIDAY NIGHT AND SATURDAY ALONG WITH A GOOD JET STREAK
DEVELOPING TO OUR NORTH AND NORTHEAST. THIS WILL PUT US IN THE
FAVORABLE RR QUADRANT. THUS...HAVE IN CHANCES OF MAINLY ELEVATED
SHOWERS/STORMS FOR FRIDAY NIGHT AND SATURDAY WITH EVERYTHING
MOVING OFF TO THE SOUTHEAST SATURDAY NIGHT. HIGHS WILL BE IN THE
80S ON FRIDAY AND A FEW DEGREES COOLER ON SATURDAY.
.LONG TERM...SUNDAY THROUGH THURSDAY
SUNDAY SHOULD PROVE TO BE THE WARMEST DAY OF THE EXTENDED
FORECAST PERIOD...WITH ANOMALOUSLY COOL AIR ADVECTING DOWN INTO
THE CWA MONDAY AND STICKING AROUND THROUGH PROBABLY WEDNESDAY...AT
LEAST. THIS SHOULD SPELL SOME MUCH BELOW NORMAL TEMPERATURES
THROUGHOUT THE PERIOD AND DRY CONDITIONS THROUGHOUT THE PERIOD.
COLD AIR INSTABILITY CU/STRATO-CU WILL LIKELY ONLY ADD INSULT TO
INJURY ON MONDAY CLOUDING THINGS UP AND KEEPING JULY INSOLATION
FROM TAKING THE EDGE OFF THE COLDNESS OF THE AIR ON MONDAY.
&&
.CLIMATOLOGICALLY...
AN ANOMALOUSLY COLD LOW PRESSURE SYSTEM WILL MOVE INTO UPPER
MIDWEST EARLY NEXT WEEK. THE COMBINATION OF A COOL CANADIAN
AIRMASS ALONG WITH INCREASING CLOUDS AND A CHANCE FOR SHOWERS
COULD RESULT IN A FEW RECORD LOW HIGH TEMPERATURES ON MONDAY.
BELOW IS A LIST OF LOCATIONS THAT COULD SEE NEAR RECORD COLD
READINGS ON MONDAY:
...LOCATION......FORECAST....RECORD LOW HIGH TEMP...
WHEATON MN 64 72 IN 1949
SISSETON 65 70 IN 1993
WATERTOWN 65 61 IN 1962
ABERDEEN 67 65 IN 1962
MOBRIDGE 69 64 IN 1962
PIERRE 72 65 IN 1989
&&
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
SCATTERED SHOWERS PERSIST ACROSS PARTS OF SOUTH CENTRAL THROUGH
NORTHEAST SOUTH DAKOTA THIS EVENING. AS A LOW LEVEL JET DEVELOPS
LATER IN THE EVENING AN INCREASE IN STORM COVERAGE AND INTENSITY
IS EXPECTED. THE BEST CHANCES FOR THUNDER REMAIN FROM SOUTH
CENTRAL SOUTH DAKOTA THROUGH NORTHEAST SOUTH DAKOTA. WILL MONITOR
SHOWER AND THUNDERSTORM ACTIVITY AND ADJUST TAFS AS NEEDED. BEYOND
REDUCED CIGS/VSBYS UNDER STRONG STORMS...MVFR/IRF CIGS ARE ALSO
LIKELY TO SETTLE IN OVER NORTHEAST SOUTH DAKOTA THROUGH THE
MORNING HOURS. A WEAK COLD FRONT IS THEN EXPECTED TO SLIDE FROM
NORTHWEST TO SOUTHEAST ACROSS THE STATE OF SOUTH DAKOTA ON FRIDAY.
ADDITIONAL SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE
BOUNDARY AND IN CONJUNCTION WITH UPPER LEVEL ENERGY FRIDAY NIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...SERR
SHORT TERM...MOHR
LONG TERM...DORN
AVIATION...SERR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1138 PM CDT TUE JUL 8 2014
.UPDATE...
UPDATED TO ADD 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1109 PM CDT TUE JUL 8 2014/
UPDATE...
UPDATED TO REMOVE WATCH. ADDITIONAL STRONG...BUT SUB SEVERE
THUNDERSTORMS WILL CONTINUE FOR SEVERAL MORE HOURS.
PREV DISCUSSION... /ISSUED 633 PM CDT TUE JUL 8 2014/
CURRENTLY...AN OUTFLOW BOUNDARY FROM THE EARLIER MCS KICKED OFF
ISOLD TO SCT TSTMS THAT ARE NOW MOVING OFF INTO ALABAMA. OTRW
THINGS ARE FAIRLY QUIET WITH CONVECTIVE DEBRIS CLOUDINESS ACROSS
THE REGION. THE AIRMASS HAS BEEN SLOWLY RECOVERING ACROSS THE
NORTH AS TEMPS CLIMB BACK INTO THE 80S WITH DEWPOINTS IN THE LOWER
70S. THE APPROACHING COLD FRONT IS LOCATED OVER SOUTHERN MISSOURI.
TONIGHT...THE COLD FRONT WILL PUSH INTO NORTHERN SECTIONS OF THE
MIDSOUTH THIS EVENING. THE AIRMASS WILL CONTINUE TO RECOVER OVER
THE NEXT COUPLE OF HOURS AND SHOWERS AND THUNDERSTORMS WILL
DEVELOP ACROSS NORTHERN SECTIONS OF THE MIDSOUTH AS THE FRONT
MOVES IN. THE 16Z HRRR DEPICTS THIS SCENARIO WITH CONVECTION
PUSHING SOUTHWARD WITH THE FRONT THROUGH THE NIGHT. A FEW STRONG
TO SEVERE STORMS WITH LOCALLY HEAVY RAIN ARE POSSIBLE AS THE FRONT
PUSHES THROUGH. THE BETTER CHANCE FOR SEVERE STORMS WILL BE NORTH
OF THE MS/TN BORDER WHERE MID LEVEL WINDS ARE STRONGER WHICH WILL
AID STORM ORGANIZATION. CURRENT HWO HANDLES THIS WELL. RAIN
CHANCE WILL SHIFT SOUTH AFTER MIDNIGHT AS THE FRONT MOVES INTO
NORTH MISSISSIPPI.
WEDNESDAY AND THURSDAY...THE FRONT WILL STALL OVER NORTH
MISSISSIPPI OR JUST TO THE SOUTH AND GRADUALLY WEAKEN. THERE WILL
BE SCT-NUMEROUS STORMS OVER NORTH MISSISSIPPI BY WED AFTERNOON AND
SOME OF THESE STORMS COULD BE STRONG TO SEVERE. HIGH PRESSURE
BUILDING INTO NORTHERN SECTIONS OF THE MID SOUTH WILL RESULT IN A
PLEASANT DAY WITH HIGHS IN THE 80S. RAIN CHANCES WILL DIMINISH
ACROSS NORTH MISSISSIPPI WED NIGHT INTO THURSDAY WITH DRY WEATHER
ACROSS NORTHERN SECTIONS. HIGHS IN THE UPPER 80S TO AROUND 90.
FRIDAY INTO SUNDAY...UPPER RIDGE STARTS TO BUILD INTO THE AREA
WITH WARMING TEMPS. LOW SUMMERTIME POPS. DID NOT GET AS
AGGRESSIVE AS THE MEX WITH RESPECT TO HIGH TEMPS.
MONDAY AND TUESDAY...UPPER TROF MOVING INTO THE GREAT LAKES WILL
PUSH ANOTHER FRONT ACROSS THE MIDSOUTH WITH CHANCE FOR SHOWERS AND
THUNDERSTORMS. COOLER BY TUESDAY.
SJM
&&
.AVIATION...
06Z TAF CYCLE
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A MESOSCALE CONVECTIVE
SYSTEM WILL GRADUALLY SHIFT SOUTH OVER THE NEXT FEW HOURS
AFFECTING TUP. THUS WILL CONTINUE WITH VCTS AND A TEMPO FOR AT
LEAST THE NEXT HOUR OR TWO. OTHERWISE...CONVECTIVE ACTIVITY NEAR
MEM/MKL WILL CONTINUE TO DIMINISH DURING THIS TIMEFRAME. LATEST
MODEL TRENDS INDICATE A POTENTIAL FOR RE-DEVELOPMENT OF VCTS AT
MEM/TUP WEDNESDAY AFTERNOON AS A COLD FRONT SLOWLY MOVES THROUGH
THE LOWER MISSISSIPPI VALLEY. MVFR/IFR CONDITIONS POSSIBLE
OVERNIGHT AT MKL FOR PATCHY FOG AND TUP WITHIN THUNDERSTORMS.
OTHERWISE...VFR CONDITIONS ANTICIPATED TO PREVAIL THROUGH MUCH OF
THE PERIOD.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1109 PM CDT TUE JUL 8 2014
.UPDATE...
UPDATED TO REMOVE WATCH. ADDITIONAL STRONG...BUT SUB SEVERE
THUNDERSTORMS WILL CONTINUE FOR SEVERAL MORE HOURS.
&&
.PREV DISCUSSION... /ISSUED 633 PM CDT TUE JUL 8 2014/
CURRENTLY...AN OUTFLOW BOUNDARY FROM THE EARLIER MCS KICKED OFF
ISOLD TO SCT TSTMS THAT ARE NOW MOVING OFF INTO ALABAMA. OTRW
THINGS ARE FAIRLY QUIET WITH CONVECTIVE DEBRIS CLOUDINESS ACROSS
THE REGION. THE AIRMASS HAS BEEN SLOWLY RECOVERING ACROSS THE
NORTH AS TEMPS CLIMB BACK INTO THE 80S WITH DEWPOINTS IN THE LOWER
70S. THE APPROACHING COLD FRONT IS LOCATED OVER SOUTHERN MISSOURI.
TONIGHT...THE COLD FRONT WILL PUSH INTO NORTHERN SECTIONS OF THE
MIDSOUTH THIS EVENING. THE AIRMASS WILL CONTINUE TO RECOVER OVER
THE NEXT COUPLE OF HOURS AND SHOWERS AND THUNDERSTORMS WILL
DEVELOP ACROSS NORTHERN SECTIONS OF THE MIDSOUTH AS THE FRONT
MOVES IN. THE 16Z HRRR DEPICTS THIS SCENARIO WITH CONVECTION
PUSHING SOUTHWARD WITH THE FRONT THROUGH THE NIGHT. A FEW STRONG
TO SEVERE STORMS WITH LOCALLY HEAVY RAIN ARE POSSIBLE AS THE FRONT
PUSHES THROUGH. THE BETTER CHANCE FOR SEVERE STORMS WILL BE NORTH
OF THE MS/TN BORDER WHERE MID LEVEL WINDS ARE STRONGER WHICH WILL
AID STORM ORGANIZATION. CURRENT HWO HANDLES THIS WELL. RAIN
CHANCE WILL SHIFT SOUTH AFTER MIDNIGHT AS THE FRONT MOVES INTO
NORTH MISSISSIPPI.
WEDNESDAY AND THURSDAY...THE FRONT WILL STALL OVER NORTH
MISSISSIPPI OR JUST TO THE SOUTH AND GRADUALLY WEAKEN. THERE WILL
BE SCT-NUMEROUS STORMS OVER NORTH MISSISSIPPI BY WED AFTERNOON AND
SOME OF THESE STORMS COULD BE STRONG TO SEVERE. HIGH PRESSURE
BUILDING INTO NORTHERN SECTIONS OF THE MID SOUTH WILL RESULT IN A
PLEASANT DAY WITH HIGHS IN THE 80S. RAIN CHANCES WILL DIMINISH
ACROSS NORTH MISSISSIPPI WED NIGHT INTO THURSDAY WITH DRY WEATHER
ACROSS NORTHERN SECTIONS. HIGHS IN THE UPPER 80S TO AROUND 90.
FRIDAY INTO SUNDAY...UPPER RIDGE STARTS TO BUILD INTO THE AREA
WITH WARMING TEMPS. LOW SUMMERTIME POPS. DID NOT GET AS
AGGRESSIVE AS THE MEX WITH RESPECT TO HIGH TEMPS.
MONDAY AND TUESDAY...UPPER TROF MOVING INTO THE GREAT LAKES WILL
PUSH ANOTHER FRONT ACROSS THE MIDSOUTH WITH CHANCE FOR SHOWERS AND
THUNDERSTORMS. COOLER BY TUESDAY.
SJM
&&
.AVIATION...
00Z TAF CYCLE
A COLD FRONT STRETCHING FROM SOUTHEAST MISSOURI BACK THROUGH
NORTHWEST ARKANSAS WILL MOVE SLOWLY SOUTHEAST ACROSS THE LOWER
MISSISSIPPI VALLEY FOR THE NEXT 24 HOURS. BASED ON LATEST SHORT
TERM CONVECTIVE TRENDS...HAVE ADJUSTED TIMING OF SHRA/TSRA AT TAF
SITES TO INCLUDE VCTS AND BEST CHANCES FOR TEMPOS AT JBR BETWEEN
09/01-03Z...MKL BETWEEN 09/00-02Z...MEM BETWEEN 09/01-03Z...AND
TUP BETWEEN 09/04-06Z. VFR CONDITIONS SHOULD PREVAIL THROUGH THE
PERIOD WITH OCCASIONAL REDUCTIONS TO MVFR/IFR CONDITIONS IN
THUNDERSTORMS AND PERHAPS SOME PATCHY FOG REDUCING VISIBILITIES AT
MKL BETWEEN 09/09-13Z. ADDITIONAL VCTS DEVELOPMENT POSSIBLE AT
MEM/TUP MAINLY AFTER 09/18Z. SOUTH/SOUTHWEST WINDS WILL GRADUALLY
VEER NORTHWEST/NORTH WITH PASSAGE OF COLD FRONT.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1221 PM CDT WED JUL 9 2014
.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
VFR CONDS EXPECTED FOR THE NEXT 24 HOURS WITH ONLY SOME PATCHY FOG
AT KCXO/KLBX AND POSSIBLY KSGR AROUND SUNRISE. THE HI-RES ARW...
THE HRRR AND THE RAP 13 SHOW SOME ISOLATED SHRA/TSRA DEVELOP NEAR
KSGR LATE THIS AFTN SO TOSSED IN A VCTS FOR THAT LOCATION ONLY.
CONVECTIVE TEMPS ARE AROUND 94 DEGREES. ON THURSDAY...THE NAM 12
IS MUCH MORE AGGRESSIVE WITH MOISTURE LEVELS WHILE THE GFS REMAINS
DRY. COULD GET SOME SHRA/TSRA AT KIAH AROUND 21Z THURSDAY BUT DID
NOT MENTION AT THIS TIME. 43
&&
.PREV DISCUSSION... /ISSUED 1040 AM CDT WED JUL 9 2014/
UPDATE...
SOUTHEASTERN TEXAS ENVIRONMENT IS RELATIVELY DRIER THAN IN RECENT
DAYS WITH SATELLITE-DERIVED PWATS AROUND 1.5 INCHES. LESS MORNING
CLOUD COVER WILL TRANSLATE TO A SLIGHTLY QUICKER WARM UP INTO THE
LOWER 90S BY NOON...SOUTHWEST BREEZES BACKING TO THE SOUTH THROUGH
THE DAY. DRIER PROFILES AND HIGHER CONVECTIVE TEMPERATURES IN THE
MIDDLE 90S WILL SIGNIFICANTLY LIMIT PRECIPITATION AREAL COVERAGE.
20% OR LESS PROBABILITY FOR A POP-UP MID TO LATE AFTERNOON SHOWER
/ISOLATED STORM ALONG THE LOCAL BAY-SEA BREEZE BOUNDARY. HIGHER
MOISTURE ADVECTING IN FROM THE GULF TOMORROW...WITH LOWER CONVECTIVE
TEMPERATURES...IS PROVIDING MORE FAVORABLE SOUNDINGS TO INCREASE
SOUTHERN 2/3RDS POPS TO LOW CHANCE(S). LATE WEEK AND WEEKEND POPS
WILL FALL TO NEAR NIL AS (ALL LEVEL) RIDGING BEGINS TO ASSERT A
STRONGER INFLUENCE UPON EASTERN TEXAS. 31
PREV DISCUSSION... /ISSUED 505 AM CDT WED JUL 9 2014/
DISCUSSION...
NOT A LOT ON THE RADAR SCOPE THIS MORNING OVER THE COASTAL COUNTIES/
NEARSHORE WATERS. PERHAPS IN PART TO THE MID LEVEL RIDGE TRYING TO
BUILD OVER THE AREA FROM THE GULF. THIS COULD TRANSLATE TO SLIGHTLY
LESS COVERAGE FOR THIS AFTN AS WELL. WILL HAVE TO KEEP A CLOSE EYE
ON THE LARGE SWATH OF HIGH CLOUDS MOVING IN FROM THE NE TO SEE HOW
IT COULD AFFECT MAX TEMPS FOR TODAY.
SLIGHTLY INCREASED POPS FOR TOMORROW AFTN (AS A SURGE OF MOISTURE
MOVES IN FROM THE GULF) BUT THIS MAY BE IT AS FAR AS SCT PCPN FOR
SE TX THROUGH THE END OF THE WEEK/ONTO THE WEEKEND. MODELS REMAIN
BULLISH WITH THE UPPER RIDGE BUILDING/SETTLING ATOP THE REGION BY
FRI. LESS POPS/WARMER TEMPS WILL LIKELY PREVAIL INTO NEXT WEEK. 41
MARINE...
LIGHT WIND REGIME REMAINS ACROSS THE AREA. SOUTH OR SOUTHEAST WINDS
5 TO AROUND 10 KNOTS WILL PREVAIL THROUGH FRIDAY WITH A SLIGHT
INCREASE SUNDAY AS RIDGE CENTER SHIFTS EASTWARD. 45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 75 95 75 97 / 20 10 20 10 20
HOUSTON (IAH) 94 75 94 76 95 / 20 10 30 20 30
GALVESTON (GLS) 90 80 91 81 92 / 10 10 20 20 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...31
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
331 AM EDT WED JUL 9 2014
.SYNOPSIS...
A SLOW MOVING COOL FRONT WILL SLIDE SOUTHEAST INTO THE MOUNTAINS
TODAY...BEFORE DRIFTING INTO NORTH CAROLINA OVERNIGHT. WEAK HIGH
PRESSURE WILL FOLLOW THE FRONT FOR THURSDAY INTO SATURDAY. A MUCH
STRONGER COLD FRONT WILL BE PASSING THROUGH THE REGION NEXT MONDAY
AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM EDT WEDNESDAY...
WEAK COOL FRONT ALONG THE OHIO RIVER EARLY THIS MORNING WILL SLIDE SE
INTO THE AREA THIS AFTERNOON BEFORE STALLING JUST SOUTH OF THE
AREA LATE TONIGHT. RESIDUAL AXIS OF DEEPER MOISTURE STRUNG OUT
AHEAD OF THE BOUNDARY WILL BE THE MAIN CONCERN FOR ADDED
CONVECTION ESPCLY OVER THE FAR WEST EARLY THIS MORNING...AND THEN
BLUE RIDGE AND POINTS SOUTH/EAST BY MID AFTERNOON. HOWEVER IFFY AS
TO EXACTLY WHERE THE BEST COVERAGE WILL BE THIS AFTERNOON GIVEN
CLOUDS/SHRA AROUND THIS MORNING AND THEN DRYING ALOFT PER VAPOR
LOOP FROM THE NW LATER IN THE AFTERNOON. GUIDANCE HAS THE BEST
LIFT OVER THE SOUTH/SE THIS AFTERNOON WHERE THE BETTER HEATING AND
LOW LEVEL BACKED FLOW COINCIDES WITH THE RIBBON OF LEFTOVER PRE-
FRONTAL MOISTURE. THIS LOOKS TO POSSIBLY INIT ALONG THE
CENTRAL/SOUTHERN BLUE RIDGE PER FORECAST 85H THETA-E RIDGING AND
PERHAPS ALONG THE GRADIENT OF DIFFERENTIAL HEATING FROM WESTERN
CLOUDS TO STRONGER HEATING OUT EAST. WINDS ALOFT ARE WEAKER...BUT
STILL UNIDIRECTIONAL THIS AFTERNOON AS SUPPORT ALOFT LACKING...
ALTHOUGH LAPSES GIVEN HEATING REMAIN STEEP...WHILE CAPES PUSH
1500-2000 J/KG PIEDMONT PROVIDED ENOUGH INSOLATION AHEAD OF THE
FRONT. THIS SUPPORTS INCREASING CHANCE POPS TO SOME DEGREE EASTERN
HALF THIS AFTERNOON...AND ALONG THE BLUE RIDGE WHERE OLD OUTFLOW
MAY LEAD TO MORE STORM CLUSTERS...PER LATEST HRRR/HIRES-ARW OUTPUT
EARLY BEFORE DRYING ALOFT AND LOW LEVEL WEST WINDS WIN OUT. THUS
WILL KEEP SOME SEVERE MENTION IN THE HWO FOR THIS AFTERNOON AS
POPS MAY NEED TO GO HIGHER PENDING INSTABILITY LATER ON.
HIGHS A BIT TRICKY GIVEN EXTENSIVE EARLY MORNING CLOUDS AND SLIGHT
COOLING ALOFT. HOWEVER APPEARS ENOUGH OF A WEST WIND TO HELP SCOUR
CLOUDS OUT OF THE EAST...WITH SOME BREAKS ESPCLY NW SO UPPED TEMPS A
FEW DEGREES BUT OVERALL STILL AOB MOS OUTSIDE OF THE SE.
BOUNDARY SINKS ACROSS AND JUST SOUTH OF THE REGION LATE TONIGHT BUT MAY
BE SLOWER THAN GUIDANCE GIVEN A WEAK WAVE ALONG THE FRONT. THIS SHOULD
BE ENOUGH TO KEEP A FEW SHRA/TSRA BANDS GOING OVER THE FAR SOUTH/SE
MAINLY BEFORE MIDNIGHT WITH GRADUAL DRYING TAKING PLACE OVER THE NW
THIRD WHERE EVEN DEWPOINTS SHOULD FALL A BIT. THEREFORE STAYED WITH
CHANCE POPS MAINLY SE OF A LYH TO HLX LINE THIS EVENING AND CUT TO JUST
ISOLATED MENTION FAR SOUTHERN COUNTIES LATE. OTRW PARTLY TO MOSTLY
CLOUDY WITH MORE CLEARING WORKING IN ACROSS THE NW LATE WHICH SHOULD
ALLOW A RANGE IN LOWS FROM THE SLIGHTLY COOLER UPPER 50S/LOW 60S NW TO
THE STILL MUGGY MID/UPPER 60S SE.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 310 AM EDT WEDNESDAY...
AN UPPER LEVEL TROUGH WILL REMAIN OVER THE EAST COAST THROUGH THE
PERIOD. MEANWHILE...A SURFACE HIGH PRESSURE SYSTEM WILL DRIFT EAST
FROM THE GREAT LAKES TO NEW ENGLAND. ACROSS THE SOUTHEAST...A
STALLED FRONTAL BOUNDARY IS EXPECTED TO MOVE NORTH AND
WEST...EVENTUALLY BUCKLING BACK OVER THE FORECAST AREA ON
THURSDAY...AS A SURFACE REFLECTION DEVELOPS OVER THE CAROLINAS. THIS
BOUNDARY AND ASSOCIATED SURFACE WAVES WILL BRING SHOWERS ALONG AND
EAST OF THE BLUE RIDGE...PARTICULARLY THE PIEDMONT THURSDAY...AND TO
SOUTHSIDE FRIDAY. INSTABILITIES WILL INCREASE FROM EAST TO WEST
THURSDAY AFTERNOON TO BRING A CHANCE FOR THUNDERSTORMS ACROSS THE
PIEDMONT. DESPITE THE INCREASE IN MOISTURE AND
INSTABILITIES...STORMS ARE NOT EXPECTED TO BECOME SEVERE. AREAL
COVERAGE OF SHOWERS WILL DECREASE THURSDAY EVENING WITH LOSE OF
HEATING AND THE FRONTAL BOUNDARY DRIFTING EAST. LESS ACTIVITY AND
AREAL COVERAGE OF SHOWERS FRIDAY.
BEING MOSTLY BEHIND THE FRONT AND HAVING AN EASTERLY FLOW AND
ABUNDANT CLOUD COVER WILL KEEP THURSDAY AFTERNOON TEMPERATURES BELOW
NORMAL. EASTERLY FLOW REMAINS FRIDAY BUT MORE SUN IS EXPECTED TO
HAVE TEMPERATURES APPROACHING NORMAL LEVELS ONCE AGAIN.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 310 PM EDT TUESDAY...
DAILY THREAT OF WIDELY SCATTERED TO SCATTERED DIURNALLY DRIVEN
SHOWERS/THUNDERSTORMS APPEARS TO BE IN THE OFFING DURING THE LONG
TERM PERIOD AS A SERIES OF WEAK SHORT WAVES IN RELATIVELY ZONAL FLOW
FORECAST TO MOVE EAST THROUGH THE BLACKSBURG FORECAST AREA.
FIRST WAVE EXPECTED ON SATURDAY...WITH SECOND WAVE ON SUNDAY...TO BE
FOLLOWED BY MUCH MORE SUBSTANTIAL WAVE IN MONDAY/TUESDAY TIMEFRAME
AS EASTERN CANADIAN UPPER LOW AMPLIFIES AND RETROGRESSES
SOUTHWESTWARD INTO THE UPPER GREAT LAKES AREA.
DEEPENING VERY BROAD UPPER TROF/CLOSED SYSTEM WILL SUPPORT A GOOD
PUSH OF UNUSUALLY COOL AIR INTO THE MID APPALACHIAN AND MID ATLANTIC
REGION BY THE END OF THE LONG TERM PERIOD...BUT WITH THE COOLEST
PORTION OF THE AIRMASS TO ARRIVE JUST OUTSIDE OF THIS FORECAST
PERIOD...ON WEDNESDAY.
AT LEAST THROUGH MONDAY...EXPECT RELATIVELY SEASONAL TEMPERATURES
WITH NO SIGNIFICANT DAY TO DAY CHANGES IN AIRMASS. HIGHS SHOULD
RANGE FROM THE MID 70S TO LOWER 80S ACROSS THE HIGHER ELEVATIONS TO
UPPER 80S TO LOWER 90S ACROSS THE PIEDMONT. OVERNIGHT LOWS SHOULD BE
GENERALLY IN THE 60S...BUT WITH SOME UPPER 50S POSSIBLE ACROSS THE
HIGHEST ELEVATIONS AND IN THE DEEPER MOUNTAIN VALLEYS. TEMPERATURES
SHOULD BEGIN TRENDING DOWNWARD ABOUT 5F DAILY BEGINNING TUESDAY AS
LEADING EDGE OF SUCCESSIVE WAVES OF COOLER AIR BEGIN TO IMPINGE UPON
THE AREA.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AS OF 100 AM EDT WEDNESDAY...
COMMS ISSUES REMAIN AT KDAN DESPITE AN INTERMITTENT RETURN OF
OBSERVATION DATA. AMD NOT SKED CONTINUED IN THE TAF.
LINGERING CONVECTION CONTINUES ACROSS THE FAR SW ATTM WITH SOME OF
THIS COVERAGE STARTING TO PUSH BACK INTO THE KBLF VICINITY. LATEST
SHORT TERM MODELS VARY ON HOW FAR EAST TO ADVANCE ADDED SHRA
OVERNIGHT WITH THE LATEST HRRR MOST AGGRESSIVE IN TAKING CLUSTERS
OF SHRA/TSRA EAST OF THE BLUE RIDGE THROUGH DAWN. MOST OTHER
SOLUTIONS KEEP THE MAJORITY ACROSS THE FAR WEST/SW WITH SHRA
WEAKENING UPON HEADING EAST. GIVEN TRENDS APPEARS SOME OF THIS
COVERAGE LIKELY TO REACH KBCB/KROA AND AFFECT KBLF AND PERHAPS
KLWB MUCH OF THE OVERNIGHT. THIS LIKELY TO KEEP MVFR/OCNL IFR
CONDITIONS IN THE SE WVA CORRIDOR WITH CIGS LOWERING HEADING EAST
BUT STILL MAINLY VFR ELSW DESPITE SOME SHOWERS AROUND. APPEARS
CLOUDS MAY LIMIT FOG BUT KEPT IN SPOTS WITH SHRA MOVING THROUGH AS
VSBYS MAY DROP ONCE THE RAIN PASSES A TERMINAL OVERNIGHT. HOWEVER
KEPT KLWB ABOVE LIFR FOR NOW GIVEN CURRENT CLOUDY TRENDS.
FRONT WILL BE SLOWLY MOVING INTO THE AREA WEDNESDAY WITH A MIX OF
MVFR TO VFR CIGS TO START THE MORNING BEFORE THINGS SLOWLY IMPROVE
TO VFR MOST SPOTS BY MIDDAY. BEST CHANCE FOR MVFR/IFR
THUNDERSTORMS ON WEDNESDAY WILL BE IN THE AFTERNOON IN CENTRAL AND
EASTERN VIRGINIA AND NORTH CAROLINA WHERE THE INSTABILITY WILL
COMBINE WITH OUTFLOW FROM PREVIOUS STORMS. HOWEVER CANT TOTALLY
RULE OUT SHRA/TSRA DEVELOPING BY LATE MORNING BLUE RIDGE GIVEN
MOISTURE AND ONSET OF HEATING. THUS GOING WITH A VCTS/VCSH FOR
MOST SPOTS BY WEDNESDAY AFTERNOON WITH COVERAGE MORE ISOLATED OVER
THE NW. DRY AIR ALOFT SHOULD START TO ARRIVE LATER IN THE
AFTERNOON ALLOWING FOR LESS CONVECTION NW THIRD WHERE WILL CUT OUT
PRECIP MENTION FROM KROA AND POINTS NW BY MID AFTERNOON WEDNESDAY.
WINDS SHOULD BE LIGHTER AND MORE WESTERLY ON WEDNESDAY JUST AHEAD
OF THE FRONT WITH A STEADY WEST/SW COMPONENT AT 5-15 KTS.
EXTENDED AVIATION...
THE COLD FRONT WILL FINALLY PUSH THROUGH THE REGION ON WEDNESDAY
NIGHT BEFORE STALLING JUST TO THE SOUTH. THIS BOUNDARY WILL
LINGER ACROSS SOUTHERN/EASTERN AREAS THROUGH THE END OF THE WEEK
WITH IMPULSES RIDING ALONG IT. THIS WILL KEEP UNSETTLED CONDITIONS
AT TAF SITES THROUGH THE END OF THE WEEK. EXPECT DIURNAL TRENDS
FOR AFTERNOON CONVECTIVE PRECIPITATION WITH ASSOCIATED MVFR OR
LOWER CONDITIONS... ESPECIALLY FOR KDAN/KLYH ON THURSDAY BUT
LIKELY LESS CONVECTION ACROSS THE AREA ON FRIDAY AND PERHAPS
SATURDAY AS WEAK HIGH PRESSURE SLIDES IN FROM THE NORTH. MOISTURE
AND MORE WIDESPREAD SHRA/TSRA LIKELY TO RETURN FOR THE END OF THE
WEEKEND AS THE FRONT RETURNS NORTH RESULTING IN PERIODS OF MVFR
CONDITIONS. OTRW PATCHY FOG RESULTING IN LOCAL MVFR TO IFR
CONDITIONS LIKELY DURING THE LATE NIGHTS AND EARLY MORNINGS ESPCLY
VALLEY LOCATIONS AND WHERE EARLIER AFTERNOON RAINFALL OCCURRED.
&&
.EQUIPMENT...
AS OF 330 AM EDT WEDNESDAY...
COMMUNICATIONS OUTAGE CONTINUES WITH KDAN ASOS NOT TRANSMITTING.
THE FAA IS AWARE OF THE OUTAGE AND WILL BE WORKING ON IT...BUT NO
ESTIMATED TIME OF WHEN IT WILL BE WORKING AGAIN.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/JH
NEAR TERM...JH
SHORT TERM...RCS
LONG TERM...AMS/WERT
AVIATION...AMS/JH/KK
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
119 AM EDT WED JUL 9 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL APPROACH FROM THE NORTHWEST OVERNIGHT
AND WEDNESDAY...BEFORE CROSSING THROUGH THE AREA WEDNESDAY NIGHT.
HIGH PRESSURE WILL FOLLOW THE FRONT FOR THURSDAY INTO SATURDAY. A
MUCH STRONGER COLD FRONT WILL BE PASSING THROUGH THE REGION NEXT
MONDAY AND TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 833 PM EDT TUESDAY...
KFCX 88D SHOWED COVERAGE AREA AND INTENSITY OF STORMS WEAKENING
DURING THE PAST HOUR OR SO. THERE IS STILL SOME DEVELOPING OF
CONVECTION ON THE EASTERN FRONT IN THE UNSTABLE AIR. SHAPED POPS
TOWARDS A BLEND OF HIRESWARW...RNK WRFARW AND HRRR. WILL CONTINUE
POPS IN THE WEST OVERNIGHT INTO WEDNESDAY MORNING.
EXPECTING LITTLE PROGRESS IN THE EASTWARD MOVEMENT OF THE SURFACE
COLD FRONT TONIGHT AND WEDNESDAY WITH BROAD SOUTHWEST FLOW
PARALLEL TO THE BOUNDARY AND LIMITED MOVEMENT OF THE UPPER TROF.
SHOWERS AND THUNDERSTORMS WILL DEVELOP AGAIN WEDNESDAY ALONG AND
AHEAD OF THE FRONTAL BOUNDARIES. SOME OF THE THUNDERSTORMS
WEDNESDAY COULD BE SEVERE WITH THE MAIN THREAT GUSTY WINDS.
AS OF 601 PM EDT TUESDAY...
UPDATED POPS FOR LATEST WSR-88D TRENDS FOR THUNDERSTORMS MOVING
ACROSS THE MOUNTAINS AT THIS TIME. SOME OF THE THUNDERSTORMS ARE
STRONG TO SEVERE WITH GUSTY WINDS THE MAIN THREAT.MODIFIED
TEMPERATURES AND DEW POINTS FOR LATEST OBS AND SHAPED THIS
EVENING INTO TONIGHT.
AS OF 315 PM EDT TUESDAY...
WATER VAPOR LOOP SHOWED THE FIRST OF TWO SHORT WAVES THAT WILL
DEEPEN THE NORTHEAST TROF. THE SECOND WAVE CROSSES THE GREAT LAKES
THEN INTO THE NORTHEAST WEDNESDAY NIGHT.
LAST FEW RUNS OF THE LOCAL WRF AND HRRR WERE VERY CONSISTENT WITH
THE TIMING OF A BAND OF THUNDERSTORMS MOVING IN FROM THE WEST...WHAT
WAS CURRENTLY DEVELOPING FROM AROUND PITTSBURGH TO NORTHWEST OF
CHARLESTON WV. STILL EXPECTING THIS TO REACH SOUTHEAST WEST VIRGINIA
BETWEEN 20-22Z/4-6PM.
GUSTY SOUTHWEST SURFACE WINDS AND LOW LEVEL MIXING HAS BROUGHT
SURFACE DEW POINTS DOWN INTO THE UPPER 50S TO LOWER 60S...SO CAPES
HAVE PEAKED AROUND 2000 J/KG. HOWEVER...AS INDICATED WITH A CLASSIC
INVERTED V SOUNDING...DCAPE WAS A HIGH AS 1300 J/KG IN THE FAR
SOUTHEAST COUNTY WARNING AREA. IF STORMS MANAGE TO GET INTO THIS
ENVIRONMENT AND OVERCOME THE DOWNSLOPING EAST OF THE BLUE RIDGE
THERE IS A POTENTIAL FOR STRONG TO DAMAGING WINDS.
WITH THE REMOVAL OF HEATING...INTENSITY AND COVERAGE OF
PRECIPITATION WILL DIMINISH...MAINLY AFTER 02Z/10PM. THE SOUTHERN
END OF THE LINE OF STORMS...EXTENDING ACROSS THE TENNESSEE VALLEY
MAY CONTINUE OVERNIGHT. HAVE KEPT A HIGHER PROBABILITY OF
PRECIPITATION IN THE SOUTHWEST COUNTY WARNING AREA THROUGH WEDNESDAY
MORNING.
EXPECTING LITTLE PROGRESS IN THE EASTWARD MOVEMENT OF THE SURFACE
COLD FRONT TONIGHT AND WEDNESDAY WITH BROAD SOUTHWEST FLOW PARALLEL
TO THE BOUNDARY AND LIMITED MOVEMENT OF THE UPPER TROF. BEST
PROBABILITY OF PRECIPITATION WEDNESDAY WILL BE IN THE AFTERNOON WITH
AREAS OF SURFACE BASED IN STABILITY AND CONVERGENCE...PLUS ALONG ANY
OUTFLOW PRODUCED BY THE THUNDERSTORMS THAT DEVELOP THIS AFTERNOON.
NARROWING DOWN WHERE THIS WILL BE IS THE BIGGEST CHALLENGE.
LOOKING FOR MUGGY CONDITIONS WILL DEW POINTS RISING BACK UP THROUGH
THE 60S TONIGHT...ESPECIALLY WHERE IT RAINS. AMOUNT OF CLOUDS WILL
DETERMINE HOW HOT TEMPERATURES WILL GET ON WEDNESDAY. WILL BE
DEPENDENT ON WHERE IT IS RAINING IN THE MORNING. FOR NOW STAYED
CLOSED TO THE MET GUIDANCE FOR MAXIMUM TEMPERATURES.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
AS OF 310 PM EDT TUESDAY...
WEAK COOL FRONT EXPECTED TO DRIFT SOUTHEAST THROUGH THE BLACKSBURG
FORECAST AREA WEDNESDAY NIGHT. ACTUAL SURFACE REFLECTION WILL LIKELY
BE DIFFICULT TO DEFINE CONSIDERING DIFFUSE NATURE OF FRONT...AND
CONTAMINATION FROM COOL OUTFLOW BOUNDARIES GENERATED BY CONVECTIVE
ACTIVITY PRECEDING IT. HOWEVER...UPPER TROF WILL REMAIN TO THE
WEST...AND WITH SUBTLE BACKING OF LOW LEVEL FLOW EXPECTED AHEAD OF
UPPER TROF...ALONG WITH GRADUAL COOLING ALOFT...SUPPORT FOR PRE- AND
POST-FRONTAL PRECIPITATION MAY PERSIST WELL INTO THE EVENING...AND
PERHAPS THOUGH MUCH OF THE NIGHT ACROSS SOUTHERN/SOUTHEASTERN AREAS.
NORTHWESTERN AREAS SHOULD REMAIN DRY...OTHER THAN PERHAPS A
LINGERING EARLY EVENING SHOWER.
ALTHOUGH NORTHWESTERN AREAS EXPECTED TO REMAIN DRY ON
THURSDAY...PROXIMITY OF OLD FRONTAL BOUNDARY LYING JUST TO THE SOUTH
AND EAST...AND LIMITED ADDITIONAL MOVEMENT EAST OF UPPER TROF
WARRANTS CONTINUED AT LEAST LOW THREAT FOR DIURNALLY DRIVEN SHOWERS
OR THUNDERSTORMS ACROSS THE SOUTH AND SOUTHEAST PORTION OF
THE FORECAST AREA DURING THE AFTERNOON INTO THE EVENING.
UPPER TROF FINALLY EXPECTED TO MOVE OVER AND THEN JUST TO THE EAST
OF THE FORECAST AREA ON FRIDAY...BUT PLACEMENT SUPPORTS
AMPLIFICATION OF SURFACE RIDGE JUST TO OUR NORTHEAST WHICH ALLOWS
LOW LEVEL FLOW TO VEER AROUND BY DAYS END INTO THE EAST. COMBINATION
OF COOLER AIR ALOFT...PLENTY OF INSOLATION...AND LIGHT UPSLOPING
AGAINST THE EASTERN FLANKS OF THE BLUE RIDGE MAY BE SUFFICIENT TO
OVERCOME DEVELOPING CAP TO SUPPORT ISOLATED TO WIDELY SCATTERED
CONVECTION ALONG AND EAST OF THE BLUE RIDGE BEFORE DIMINISHING WITH
LOSS OF DAYTIME HEATING FRIDAY EVENING.
POST FRONTAL TEMPERATURES WILL BE SLIGHTLY COOLER THAN THE PAST
SEVERAL DAYS...MAINLY 70S TO AROUND 80 ACROSS THE HIGHER ELEVATIONS
TO MAINLY 80S PIEDMONT...WITH 50S IN THE MOUNTAIN VALLEYS TO MAINLY
60S ACROSS THE PIEDMONT AT NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 310 PM EDT TUESDAY...
DAILY THREAT OF WIDELY SCATTERED TO SCATTERED DIURNALLY DRIVEN
SHOWERS/THUNDERSTORMS APPEARS TO BE IN THE OFFING DURING THE LONG
TERM PERIOD AS A SERIES OF WEAK SHORT WAVES IN RELATIVELY ZONAL FLOW
FORECAST TO MOVE EAST THROUGH THE BLACKSBURG FORECAST AREA.
FIRST WAVE EXPECTED ON SATURDAY...WITH SECOND WAVE ON SUNDAY...TO BE
FOLLOWED BY MUCH MORE SUBSTANTIAL WAVE IN MONDAY/TUESDAY TIMEFRAME
AS EASTERN CANADIAN UPPER LOW AMPLIFIES AND RETROGRESSES
SOUTHWESTWARD INTO THE UPPER GREAT LAKES AREA.
DEEPENING VERY BROAD UPPER TROF/CLOSED SYSTEM WILL SUPPORT A GOOD
PUSH OF UNUSUALLY COOL AIR INTO THE MID APPALACHIAN AND MID ATLANTIC
REGION BY THE END OF THE LONG TERM PERIOD...BUT WITH THE COOLEST
PORTION OF THE AIRMASS TO ARRIVE JUST OUTSIDE OF THIS FORECAST
PERIOD...ON WEDNESDAY.
AT LEAST THROUGH MONDAY...EXPECT RELATIVELY SEASONAL TEMPERATURES
WITH NO SIGNIFICANT DAY TO DAY CHANGES IN AIRMASS. HIGHS SHOULD
RANGE FROM THE MID 70S TO LOWER 80S ACROSS THE HIGHER ELEVATIONS TO
UPPER 80S TO LOWER 90S ACROSS THE PIEDMONT. OVERNIGHT LOWS SHOULD BE
GENERALLY IN THE 60S...BUT WITH SOME UPPER 50S POSSIBLE ACROSS THE
HIGHEST ELEVATIONS AND IN THE DEEPER MOUNTAIN VALLEYS. TEMPERATURES
SHOULD BEGIN TRENDING DOWNWARD ABOUT 5F DAILY BEGINNING TUESDAY AS
LEADING EDGE OF SUCCESSIVE WAVES OF COOLER AIR BEGIN TO IMPINGE UPON
THE AREA.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 100 AM EDT WEDNESDAY...
COMMS ISSUES REMAIN AT KDAN DESPITE AN INTERMITTENT RETURN OF
OBSERVATION DATA. AMD NOT SKED CONTINUED IN THE TAF.
LINGERING CONVECTION CONTINUES ACROSS THE FAR SW ATTM WITH SOME OF
THIS COVERAGE STARTING TO PUSH BACK INTO THE KBLF VICINITY. LATEST
SHORT TERM MODELS VARY ON HOW FAR EAST TO ADVANCE ADDED SHRA
OVERNIGHT WITH THE LATEST HRRR MOST AGGRESSIVE IN TAKING CLUSTERS
OF SHRA/TSRA EAST OF THE BLUE RIDGE THROUGH DAWN. MOST OTHER
SOLUTIONS KEEP THE MAJORITY ACROSS THE FAR WEST/SW WITH SHRA
WEAKENING UPON HEADING EAST. GIVEN TRENDS APPEARS SOME OF THIS
COVERAGE LIKELY TO REACH KBCB/KROA AND AFFECT KBLF AND PERHAPS
KLWB MUCH OF THE OVERNIGHT. THIS LIKELY TO KEEP MVFR/OCNL IFR
CONDITIONS IN THE SE WVA CORRIDOR WITH CIGS LOWERING HEADING EAST
BUT STILL MAINLY VFR ELSW DESPITE SOME SHOWERS AROUND. APPEARS
CLOUDS MAY LIMIT FOG BUT KEPT IN SPOTS WITH SHRA MOVING THROUGH AS
VSBYS MAY DROP ONCE THE RAIN PASSES A TERMINAL OVERNIGHT. HOWEVER
KEPT KLWB ABOVE LIFR FOR NOW GIVEN CURRENT CLOUDY TRENDS.
FRONT WILL BE SLOWLY MOVING INTO THE AREA WEDNESDAY WITH A MIX OF
MVFR TO VFR CIGS TO START THE MORNING BEFORE THINGS SLOWLY IMPROVE
TO VFR MOST SPOTS BY MIDDAY. BEST CHANCE FOR MVFR/IFR
THUNDERSTORMS ON WEDNESDAY WILL BE IN THE AFTERNOON IN CENTRAL AND
EASTERN VIRGINIA AND NORTH CAROLINA WHERE THE INSTABILITY WILL
COMBINE WITH OUTFLOW FROM PREVIOUS STORMS. HOWEVER CANT TOTALLY
RULE OUT SHRA/TSRA DEVELOPING BY LATE MORNING BLUE RIDGE GIVEN
MOISTURE AND ONSET OF HEATING. THUS GOING WITH A VCTS/VCSH FOR
MOST SPOTS BY WEDNESDAY AFTERNOON WITH COVERAGE MORE ISOLATED OVER
THE NW. DRY AIR ALOFT SHOULD START TO ARRIVE LATER IN THE
AFTERNOON ALLOWING FOR LESS CONVECTION NW THIRD WHERE WILL CUT OUT
PRECIP MENTION FROM KROA AND POINTS NW BY MID AFTERNOON WEDNESDAY.
WINDS SHOULD BE LIGHTER AND MORE WESTERLY ON WEDNESDAY JUST AHEAD
OF THE FRONT WITH A STEADY WEST/SW COMPONENT AT 5-15 KTS.
EXTENDED AVIATION...
THE COLD FRONT WILL FINALLY PUSH THROUGH THE REGION ON WEDNESDAY
NIGHT BEFORE STALLING JUST TO THE SOUTH. THIS BOUNDARY WILL
LINGER ACROSS SOUTHERN/EASTERN AREAS THROUGH THE END OF THE WEEK
WITH IMPULSES RIDING ALONG IT. THIS WILL KEEP UNSETTLED CONDITIONS
AT TAF SITES THROUGH THE END OF THE WEEK. EXPECT DIURNAL TRENDS
FOR AFTERNOON CONVECTIVE PRECIPITATION WITH ASSOCIATED MVFR OR
LOWER CONDITIONS... ESPECIALLY FOR KDAN/KLYH ON THURSDAY BUT
LIKELY LESS CONVECTION ACROSS THE AREA ON FRIDAY AND PERHAPS
SATURDAY AS WEAK HIGH PRESSURE SLIDES IN FROM THE NORTH. MOISTURE
AND MORE WIDESPREAD SHRA/TSRA LIKELY TO RETURN FOR THE END OF THE
WEEKEND AS THE FRONT RETURNS NORTH RESULTING IN PERIODS OF MVFR
CONDITIONS. OTRW PATCHY FOG RESULTING IN LOCAL MVFR TO IFR
CONDITIONS LIKELY DURING THE LATE NIGHTS AND EARLY MORNINGS ESPCLY
VALLEY LOCATIONS AND WHERE EARLIER AFTERNOON RAINFALL OCCURRED.
&&
.EQUIPMENT...
AS OF 315 PM EDT TUESDAY...
COMMUNICATIONS OUTAGE CONTINUES WITH KDAN ASOS NOT TRANSMITTING.
THE FAA IS AWARE OF THE OUTAGE AND WILL BE WORKING ON IT...BUT NO
ESTIMATED TIME OF WHEN IT WILL BE WORKING AGAIN.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...WERT
LONG TERM...AMS/WERT
AVIATION...AMS/JH/KK
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
645 AM CDT WED JUL 9 2014
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 336 AM CDT WED JUL 9 2014
ANALYSIS OF WATER VAPOR LOOP AND RAP 500MB LEVEL SHOWING AN
ANOMALOUSLY DEEP LONGWAVE TROUGH CARVED OUT OVER THE GREAT
LAKES/MISSISSIPPI VALLEY REGION WHILE RIDGING CONTINUES OVER THE
WESTERN CONUS. A SHORTWAVE TROUGH WITHIN THE MAIN LONGWAVE TROUGH
WAS ROTATING SOUTHEAST THROUGH THE U.P. AND NORTHERN WI. RADAR
SHOWING SOME WEAK SHOWER ECHOES WITH THIS FEATURE. OTHERWISE...
TEMPERATURES ACROSS THE ARX FORECAST AREA WERE IN THE MIDDLE 50S TO
LOWER 60S WITH CALM TO LIGHT NORTHWEST WINDS UNDER PARTLY CLOUDY
SKIES.
FOR TODAY...LONGWAVE TROUGH BEGINS TO PUSH EAST TODAY TAKING COLDEST
POOL OF TEMPERATURE ALOFT WITH IT MORE INTO THE GREAT LAKES REGION.
NONETHELESS...FAIRLY STEEP LOW LEVEL LAPSE RATES REMAIN OVER THE
AREA MAINLY NORTHEAST OF I-94. BUFKIT SOUNDINGS SHOWING QUITE A BIT
OF CUMULUS ACROSS THAT AREA ALONG WITH THE POSSIBILITY OF SOME
SHOWERS. WILL KEEP A 20-30 PROBABILITY FOR THAT AREA. REST OF THE
AREA SHOULD SEE SCATTERED CUMULUS. OTHERWISE...LOOK FOR HIGHS IN THE
LOWER 70S ACROSS NORTH CENTRAL WI..TO THE MIDDLE AND UPPER 70S
ELSEWHERE.
FOR TONIGHT...HIGH PRESSURE BUILDS OVERHEAD FOR MOSTLY CLEAR AND
CALM CONDITIONS. THIS WILL SET UP GOOD RADIATIONAL COOLING ACROSS
THE AREA WITH LOWS TONIGHT DIPPING INTO THE MIDDLE/UPPER 40S IN THE
SAND/CRANBERRY COUNTRY OF CENTRAL WISCONSIN...AND IN THE 50S
ELSEWHERE. ALSO...AREAS OF FOG WILL BE LIKELY ACROSS THE LOWER LYING
AREAS/RIVER VALLEYS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 336 AM CDT WED JUL 9 2014
FOR THURSDAY THROUGH FRIDAY...
HIGH PRESSURE MOVES OFF TO THE EAST...SETTING UP RETURN/SOUTHERLY
FLOW ACROSS THE REGION ON THURSDAY. UNDER MOSTLY SUNNY SKIES LOOK
FOR HIGHS REBOUNDING INTO THE UPPER 70S TO THE LOWER 80S. DEW POINTS
WILL ALSO BE ON THE RISE THROUGH THE DAY FOR A SLIGHTLY MORE HUMID
FEEL.
ATTENTION THEN TURNS TO A MID-LEVEL TROUGH DROPPING SOUTHEAST FROM
THE NORTHERN PLAINS TOWARD THE UPPER MISSISSIPPI RIVER VALLEY REGION
THURSDAY NIGHT THROUGH FRIDAY WHILE A WARM FRONT SETS UP ACROSS THE
PLAINS INTO FAR SOUTHERN IA/CENTRAL IL. THIS WILL BRING A GOOD
CHANCE/LIKELIHOOD OF SHOWERS AND THUNDERSTORMS INTO THE AREA
CENTERED ON FRIDAY. THINKING ANY SEVERE THREAT SHOULD BE WELL SOUTH
OF THE AREA CLOSER TO NOSE OF 850MB MOISTURE TRANSPORT OVER THE
PLAINS WARM FRONT.
FOR SATURDAY THROUGH SUNDAY...
WILL CONTINUE TO SEE A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
SATURDAY/SATURDAY EVENING AS A WEAK COLD FRONT MOVES IN AND STALLS
ACROSS THE AREA. GFS BUFKIT SHOWING 1000-2000J/KG OF MLCAPE ACROSS
THE AREA WITH 0-3KM BULK SHEAR IN THE 10-15KT RANGE IN THE BEST CAPE
POOL. SO...AN ISOLATED SEVERE PULSE-MODE STORM CANNOT BE RULED
OUT...BUT WIDESPREAD SEVERE NOT EXPECTED AT THIS TIME.
SHOWER/THUNDERSTORM CHANCES CONTINUE THROUGH SUNDAY AS WELL AS A MID-
LEVEL TROUGH/SURFACE TROUGH DROPS OUT OF SOUTHERN CANADA/NORTHERN
PLAINS TOWARD THE AREA. GFS A BIT FASTER WITH THIS FEATURE THAN THE
ECMWF...SO TIMING NOT SET IN STONE. GFS SHOWING MLCAPE IN THE 1000-
1500J/KG RANGE WITH A LITTLE BETTER 0-3KM SHEAR AROUND 20KT. WILL
HAVE TO KEEP AN EYE ON THE TIMING OF THIS FEATURE AND SEVERE THREAT.
FOR MONDAY INTO TUESDAY...COOLER AIR FILTERS INTO THE AREA AS AN
ANOMALOUSLY DEEP CLOSED LOW DROPS SOUTH OUT OF CANADA TOWARD THE
REGION. WILL HAVE TO KEEP A CLOSE WATCH ON THUNDERSTORM THREAT
MONDAY WITH TIMING OF INCOMING SHORTWAVE TROUGH ENERGY/LEADING EDGE
OF COLDER AIR DURING PEAK HEATING. TUESDAY LOOKING LIKE A
COOL/CLOUDY/POSSIBLY SHOWERY DAY AS DEEP CLOSED LOW/COLD POOL ALOFT
SETTLES OVER THE AREA.
TEMPERATURE-WISE...EXPECTING TEMPERATURES IN THE UPPER 70S/LOWER 80S
ON SUNDAY...THEN COOLING INTO THE UPPER 60S/LOWER 70S BY TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 645 AM CDT WED JUL 9 2014
VFR CONDITIONS THROUGH THE PERIOD ARE EXPECTED. ALTHOUGH NOT
INCLUDED IN THE KLSE FORECAST...THERE ARE SOME PROBABILITIES FOR
VALLEY FOG THURSDAY MORNING AROUND SUNRISE. CLEAR SKIES AND LIGHT
WINDS WILL CAUSE FAVORABLE RADIATIONAL COOLING CONDITIONS
OVERNIGHT. THE LIGHT WIND LAYER AT KLSE HAS BEEN DEEPENING IN THE
MODEL GUIDANCE ALLOWING FOR A BIT BETTER SCENARIO TO DEVELOP FOG
IN THE MISS RIVER VALLEY. SOME SUGGESTION OF 6-7KFT CLOUD IS ALSO
IN THE GUIDANCE...HOWEVER CONFIDENCE ON THAT OCCURRING IS LOWER.
WILL CONTINUE TO MONITOR FOR THE INCLUSION OF FOG AT KLSE IN
FUTURE TAFS FOR THURSDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 336 AM CDT WED JUL 9 2014
THE MISSISSIPPI RIVER LEVEL CONTINUES TO FALL. MCGREGOR AND
GUTTENBERG IOWA ARE THE ONLY ARX FORECAST POINTS THAT REMAIN IN
FLOOD. THESE POINTS ARE EXPECTED TO FALL BELOW FLOOD STAGE BY
THURSDAY. FOR THE CURRENT AND FORECAST RIVER LEVELS...SEE OUR
INTERNET PAGE AT WWW.WEATHER.GOV/LACROSSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...BAUMGARDT
HYDROLOGY...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
336 AM CDT WED JUL 9 2014
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 336 AM CDT WED JUL 9 2014
ANALYSIS OF WATER VAPOR LOOP AND RAP 500MB LEVEL SHOWING AN
ANOMALOUSLY DEEP LONGWAVE TROUGH CARVED OUT OVER THE GREAT
LAKES/MISSISSIPPI VALLEY REGION WHILE RIDGING CONTINUES OVER THE
WESTERN CONUS. A SHORTWAVE TROUGH WITHIN THE MAIN LONGWAVE TROUGH
WAS ROTATING SOUTHEAST THROUGH THE U.P. AND NORTHERN WI. RADAR
SHOWING SOME WEAK SHOWER ECHOES WITH THIS FEATURE. OTHERWISE...
TEMPERATURES ACROSS THE ARX FORECAST AREA WERE IN THE MIDDLE 50S TO
LOWER 60S WITH CALM TO LIGHT NORTHWEST WINDS UNDER PARTLY CLOUDY
SKIES.
FOR TODAY...LONGWAVE TROUGH BEGINS TO PUSH EAST TODAY TAKING COLDEST
POOL OF TEMPERATURE ALOFT WITH IT MORE INTO THE GREAT LAKES REGION.
NONETHELESS...FAIRLY STEEP LOW LEVEL LAPSE RATES REMAIN OVER THE
AREA MAINLY NORTHEAST OF I-94. BUFKIT SOUNDINGS SHOWING QUITE A BIT
OF CUMULUS ACROSS THAT AREA ALONG WITH THE POSSIBILITY OF SOME
SHOWERS. WILL KEEP A 20-30 PROBABILITY FOR THAT AREA. REST OF THE
AREA SHOULD SEE SCATTERED CUMULUS. OTHERWISE...LOOK FOR HIGHS IN THE
LOWER 70S ACROSS NORTH CENTRAL WI..TO THE MIDDLE AND UPPER 70S
ELSEWHERE.
FOR TONIGHT...HIGH PRESSURE BUILDS OVERHEAD FOR MOSTLY CLEAR AND
CALM CONDITIONS. THIS WILL SET UP GOOD RADIATIONAL COOLING ACROSS
THE AREA WITH LOWS TONIGHT DIPPING INTO THE MIDDLE/UPPER 40S IN THE
SAND/CRANBERRY COUNTRY OF CENTRAL WISCONSIN...AND IN THE 50S
ELSEWHERE. ALSO...AREAS OF FOG WILL BE LIKELY ACROSS THE LOWER LYING
AREAS/RIVER VALLEYS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 336 AM CDT WED JUL 9 2014
FOR THURSDAY THROUGH FRIDAY...
HIGH PRESSURE MOVES OFF TO THE EAST...SETTING UP RETURN/SOUTHERLY
FLOW ACROSS THE REGION ON THURSDAY. UNDER MOSTLY SUNNY SKIES LOOK
FOR HIGHS REBOUNDING INTO THE UPPER 70S TO THE LOWER 80S. DEW POINTS
WILL ALSO BE ON THE RISE THROUGH THE DAY FOR A SLIGHTLY MORE HUMID
FEEL.
ATTENTION THEN TURNS TO A MID-LEVEL TROUGH DROPPING SOUTHEAST FROM
THE NORTHERN PLAINS TOWARD THE UPPER MISSISSIPPI RIVER VALLEY REGION
THURSDAY NIGHT THROUGH FRIDAY WHILE A WARM FRONT SETS UP ACROSS THE
PLAINS INTO FAR SOUTHERN IA/CENTRAL IL. THIS WILL BRING A GOOD
CHANCE/LIKELIHOOD OF SHOWERS AND THUNDERSTORMS INTO THE AREA
CENTERED ON FRIDAY. THINKING ANY SEVERE THREAT SHOULD BE WELL SOUTH
OF THE AREA CLOSER TO NOSE OF 850MB MOISTURE TRANSPORT OVER THE
PLAINS WARM FRONT.
FOR SATURDAY THROUGH SUNDAY...
WILL CONTINUE TO SEE A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH
SATURDAY/SATURDAY EVENING AS A WEAK COLD FRONT MOVES IN AND STALLS
ACROSS THE AREA. GFS BUFKIT SHOWING 1000-2000J/KG OF MLCAPE ACROSS
THE AREA WITH 0-3KM BULK SHEAR IN THE 10-15KT RANGE IN THE BEST CAPE
POOL. SO...AN ISOLATED SEVERE PULSE-MODE STORM CANNOT BE RULED
OUT...BUT WIDESPREAD SEVERE NOT EXPECTED AT THIS TIME.
SHOWER/THUNDERSTORM CHANCES CONTINUE THROUGH SUNDAY AS WELL AS A MID-
LEVEL TROUGH/SURFACE TROUGH DROPS OUT OF SOUTHERN CANADA/NORTHERN
PLAINS TOWARD THE AREA. GFS A BIT FASTER WITH THIS FEATURE THAN THE
ECMWF...SO TIMING NOT SET IN STONE. GFS SHOWING MLCAPE IN THE 1000-
1500J/KG RANGE WITH A LITTLE BETTER 0-3KM SHEAR AROUND 20KT. WILL
HAVE TO KEEP AN EYE ON THE TIMING OF THIS FEATURE AND SEVERE THREAT.
FOR MONDAY INTO TUESDAY...COOLER AIR FILTERS INTO THE AREA AS AN
ANOMALOUSLY DEEP CLOSED LOW DROPS SOUTH OUT OF CANADA TOWARD THE
REGION. WILL HAVE TO KEEP A CLOSE WATCH ON THUNDERSTORM THREAT
MONDAY WITH TIMING OF INCOMING SHORTWAVE TROUGH ENERGY/LEADING EDGE
OF COLDER AIR DURING PEAK HEATING. TUESDAY LOOKING LIKE A
COOL/CLOUDY/POSSIBLY SHOWERY DAY AS DEEP CLOSED LOW/COLD POOL ALOFT
SETTLES OVER THE AREA.
TEMPERATURE-WISE...EXPECTING TEMPERATURES IN THE UPPER 70S/LOWER 80S
ON SUNDAY...THEN COOLING INTO THE UPPER 60S/LOWER 70S BY TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1144 PM CDT TUE JUL 8 2014
STILL SOME CLOUDS FLOATING AROUND OVER CENTRAL AND NORTHERN
WISCONSIN ALONG WITH NORTHWEST MINNESOTA LATE THIS EVENING.
HOWEVER...SATELLITE TRENDS SHOW THESE CONTINUE TO SLOWLY
DISSIPATE AND DO NOT THINK THEY WILL AFFECT EITHER TAF SITE
THROUGH THE REMAINDER OF THE NIGHT. THE 09.00Z NAM CONTINUES TO
SHOW SATURATION AT THE SURFACE OCCURRING LATE TONIGHT AT KLSE WITH
THE WINDS QUICKLY INCREASING ABOVE THE SURFACE AND THIS SHOULD BE
ENOUGH TO KEEP ANY FOG FROM FORMING. THE NAM ALSO STILL SHOWS SOME
WEAK PV ADVECTION IN THE 500-300 MB LAYER COMING ACROSS THE AREA
LATE WEDNESDAY AFTERNOON BUT THE LATEST BUFKIT SOUNDING FOR KLSE
SHOWS SUBSIDENCE OCCURRING. THE NAM STILL PRODUCES SOME
SHOWERS...BUT THESE ARE OVER NORTHEAST WISCONSIN IN AGREEMENT WITH
THE 08.12Z ECMWF AND 09.21Z SREF AND DO NOT PLAN TO INCLUDE ANY
SHOWERS IN EITHER TAF.
&&
.HYDROLOGY...
ISSUED AT 336 AM CDT WED JUL 9 2014
THE MISSISSIPPI RIVER LEVEL CONTINUES TO FALL. MCGREGOR AND
GUTTENBERG IOWA ARE THE ONLY ARX FORECAST POINTS THAT REMAIN IN
FLOOD. THESE POINTS ARE EXPECTED TO FALL BELOW FLOOD STAGE BY
THURSDAY. FOR THE CURRENT AND FORECAST RIVER LEVELS...SEE OUR
INTERNET PAGE AT WWW.WEATHER.GOV/LACROSSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...04
HYDROLOGY...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1144 PM CDT TUE JUL 8 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 308 PM CDT TUE JUL 8 2014
MAIN SHORT TERM FORECAST CONCERNS ARE ON SHOWER CHANCES THROUGH
WEDNESDAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE WESTERN U.S. INTO SOUTHWEST CANADA...WHILE
TROUGHING WAS IN PLACE FROM HUDSON BAY INTO THE WESTERN GREAT LAKES
REGION. TWO MAIN SHORTWAVES OF NOTE WERE OVER NORTHERN WI AND
CENTRAL MANITOBA. COOL AIR ALOFT WITH THE SHORTWAVES ARE COMBINING
WITH DAYTIME INSTABILITY TO PRODUCE SHOWERS AND A FEW THUNDERSTORMS.
THAT COOL AIR ALOFT WAS EVIDENT EVEN AT 850MB WITH 12Z SOUNDINGS AT
MPX AND GRB OF 12C AND AT INL OF 9C. THESE COOL 850MB TEMPS HAVE
HELD TEMPERATURES MOSTLY IN THE 70S TODAY. DEWPOINTS HAVE MIXED DOWN
INTO THE 50S THANKS TO A FLOW OF DRY AIR ON BREEZY NORTHWEST WINDS.
THIS DRY AIR OVER THE NORTHERN PLAINS HAD PRECIPITABLE WATER VALUES
OF 0.5-1 INCH PER 12Z SOUNDINGS...OR 50-100 PERCENT OF NORMAL.
MAIN FOCUS FOR THE SHORT TERM IS ON THE SHORTWAVE OVER CENTRAL
MANITOBA. MODELS PROG THIS SHORTWAVE TO ROUND THE TROUGH AND CROSS
NORTHERN WI BETWEEN 03-09Z. ALTHOUGH THE SHORTWAVE IS COMING ACROSS
DURING THE NOCTURNAL HOURS...CANNOT RULE OUT A FEW SHOWERS WITH IT
GIVEN THE STRENGTH OF THE WAVE. SEEMS LIKE THE TRACK OF THE WAVE
WILL KEEP THE MAJORITY OF THE SHOWER ACTIVITY NORTHEAST OF THE
FORECAST AREA...BUT JUST IN CASE DID HOLD ONTO A 20 PERCENT CHANCE
ACROSS TAYLOR IN THE EVENING HOURS.
COOLER AIR ALOFT LOOKS TO LINGER INTO WEDNESDAY FOR LOCATIONS
ALONG/NORTHEAST OF I-94...AIDED BY THE TAIL END OF THE SHORTWAVE
COMING ACROSS TONIGHT HANGING BACK. IN FACT...850MB TEMPS ARE
PROGGED ABOUT 1C COOLER ON WEDNESDAY COMPARED TO TODAY...RANGING
FROM 9-11C. THE COOL AIR ALOFT COMBINED WITH DAYTIME HEATING AND
EVAPOTRANSPORATION COULD BE ENOUGH TO SPARK A FEW MORE SHOWERS
ALONG/NORTHEAST OF I-94. THUS...HAVE MAINTAINED THE CHANCES THAT
WERE INTRODUCED LAST NIGHT.
EXPECT DRY WEATHER OUTSIDE OF THE AFOREMENTIONED PRECIPITATION
CHANCES...WITH PERSISTENT DRY ADVECTION FROM THE NORTHWEST AIDING AN
OVERALL GRADUAL FALL IN DEWPOINTS THE NEXT 24 HOURS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 308 PM CDT TUE JUL 8 2014
LONG TERM HIGHLIGHTS INCLUDE COOL WEDNESDAY NIGHT...POTENTIAL
CONVECTION THURSDAY NIGHT THROUGH THE WEEKEND...AND A MUCH BELOW
NORMAL AIRMASS FOR EARLY NEXT WEEK.
WEDNESDAY NIGHT AND THURSDAY FEATURES BUILDING UPPER RIDGING AHEAD
OF AN UPPER TROUGH CROSSING SOUTHWEST CANADA. SUBSIDENCE UNDER THIS
BUILDING RIDGE...HIGH PRESSURE MOVING IN PLACE AT THE SURFACE AND
PRECIPITABLE WATER PROGGED IN THE 0.5-1 INCH RANGE WILL RESULT IN
DRY CONDITIONS. THE CONDITIONS ALSO FAVOR GOOD RADIATIONAL COOLING
FOR WEDNESDAY NIGHT. GIVEN MOISTURE POOLING IN SMALLER VALLEY AND IN
THE CRANBERRY BOG AREAS...THE COOLER NIGHT WILL LIKELY LEAD TO SOME
FOG IN THESE LOCATIONS. THE AIR MAY BE TOO DRY TO ALLOW THE
MISSISSIPPI TO FOG. ANOTHER MONTH FROM NOW WHEN WE HAVE A LONGER
NIGHT...THIS WOULD BE A DIFFERENT STORY. TEMPERATURES SHOULD END UP
WARMER TOO ON THURSDAY AS 850MB TEMPS BEGIN TO CLIMB TO 12-14C BY
00Z.
THE WEATHER THEN GETS A BIT MORE ACTIVE THURSDAY NIGHT AND FRIDAY
DUE TO A SHORTWAVE RIDING THROUGH THE ZONAL FLOW OVER THE NORTHERN
PLAINS. MODELS HAVE HAD A CONSISTENT SIGNAL OF THIS SHORTWAVE
INDUCING A STRONG 850MB MOISTURE TRANSPORT ZONE FROM THE CENTRAL
PLAINS INTO OUR REGION. GENERAL MODEL CONSENSUS IS FOR A CONVECTIVE
COMPLEX TO FORM ON THE NOSE OF THIS MOISTURE TRANSPORT IN IOWA
THURSDAY NIGHT...WHICH CORFIDI VECTORS WOULD SUGGEST A SOUTHEAST
MOVEMENT. ALTHOUGH THIS COMPLEX MAY STAY AWAY FROM THE AREA...IT
APPEARS THERE SHOULD BE ENOUGH OF THIS MOISTURE TRANSPORT AIMING UP
AT US TO COMBINE WITH DPVA FROM THE SHORTWAVE TO GENERATE SHOWERS
AND THUNDERSTORMS FARTHER NORTH. THUS...HAVE MAINTAINED HIGH
PRECIPITATION CHANCES...50-70...CENTERED ON THE 06-18Z FRIDAY
PERIOD. THIS PRECIPITATION AND ASSOCIATED CLOUDS WILL HELP KEEP IT
COOLER ON FRIDAY TEMPERATURE WISE...DESPITE 850MB TEMPS RISING TO 14-
17C. DEWPOINTS ARE GOING TO BE ON THE RISE...THOUGH...MAKING IT FEEL
MORE MUGGY.
FOR FRIDAY NIGHT INTO THE WEEKEND...ITS A VERY UNCERTAIN FORECAST.
THERE IS VERY GOOD MODEL AGREEMENT ON UPPER TROUGHING DROPPING SOUTH
FROM CENTRAL CANADA INTO THE WESTERN GREAT LAKES REGION...BUT
DETAILS WITHIN THE TROUGH VARY FROM MODEL TO MODEL. THESE DETAILS
IMPACT FRONTAL BOUNDARIES DROPPING THROUGH THE REGION AND THUS WHERE
CONVECTION CAN FIRE. CERTAINLY APPEARS THAT WE COULD DEAL WITH A
COUPLE BOUTS OF CONVECTION...BUT FOR NOW HAVE TO BLANKET MUCH OF THE
WEEKEND WITH 20-40 PERCENT CHANCES UNTIL DETAILS CAN SORT THEMSELVES
OUT. SHOULD BE A GENERAL COOLING TREND HEADING INTO
SUNDAY...THOUGH.
THE FORECAST BECOMES MORE CERTAIN EARLY NEXT WEEK WITH THE ECMWF AND
GFS NOW IN-SYNC HAVING AN ANOMALOUSLY DEEP UPPER LOW DROP DOWN INTO
THE LAKE SUPERIOR REGION BY MONDAY EVENING. THE ECMWF AND GFS
ENSEMBLES ARE ALSO TRENDING TOWARDS THIS SCENARIO. BACKING TRACKING
THE UPPER LOW...IT ORIGINATES RIGHT NOW FROM THE ARCTIC...A
SITUATION SIMILAR TO WHAT WE SAW DURING THE WINTER. THUS...850MB
TEMPS TANK EARLY NEXT WEEK...DROPPING TO AS LOW AS +2C AT 12Z
TUESDAY. THE 08.00Z ECMWF STRUGGLES TO GET LA CROSSE UP TO 65 FOR
TUESDAY...WHICH WOULD BREAK THE RECORD MINIMUM HIGH TEMPERATURE OF
68 SET IN 1962. DID NOT GO THAT COLD YET SINCE IT IS 7 DAYS
OUT...BUT KEPT IT MUCH BELOW NORMAL WITH HIGHS OF UPPER 60S TO LOW
70S. ALSO HAVE SOME LOW CHANCES OF RAIN GIVEN THE COOL AIR
ALOFT...THOUGH ITS POSSIBLE THE AIR WILL BE DRY ENOUGH TO PREVENT
ANY PRECIPITATION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1144 PM CDT TUE JUL 8 2014
STILL SOME CLOUDS FLOATING AROUND OVER CENTRAL AND NORTHERN
WISCONSIN ALONG WITH NORTHWEST MINNESOTA LATE THIS EVENING.
HOWEVER...SATELLITE TRENDS SHOW THESE CONTINUE TO SLOWLY
DISSIPATE AND DO NOT THINK THEY WILL AFFECT EITHER TAF SITE
THROUGH THE REMAINDER OF THE NIGHT. THE 09.00Z NAM CONTINUES TO
SHOW SATURATION AT THE SURFACE OCCURRING LATE TONIGHT AT KLSE WITH
THE WINDS QUICKLY INCREASING ABOVE THE SURFACE AND THIS SHOULD BE
ENOUGH TO KEEP ANY FOG FROM FORMING. THE NAM ALSO STILL SHOWS SOME
WEAK PV ADVECTION IN THE 500-300 MB LAYER COMING ACROSS THE AREA
LATE WEDNESDAY AFTERNOON BUT THE LATEST BUFKIT SOUNDING FOR KLSE
SHOWS SUBSIDENCE OCCURRING. THE NAM STILL PRODUCES SOME
SHOWERS...BUT THESE ARE OVER NORTHEAST WISCONSIN IN AGREEMENT WITH
THE 08.12Z ECMWF AND 09.21Z SREF AND DO NOT PLAN TO INCLUDE ANY
SHOWERS IN EITHER TAF.
&&
.HYDROLOGY...
ISSUED AT 308 PM CDT TUE JUL 8 2014
WATER LEVELS CONTINUE TO FALL ON THE MISSISSIPPI RIVER. WE ARE
EXPECTING ALL THE RIVER FORECAST POINTS WITHIN THE ARX FORECAST AREA
TO FALL BELOW FLOOD STAGE BY THURSDAY FROM NORTH TO SOUTH. FOR
THE CURRENT AND FORECAST RIVER LEVELS...SEE OUR INTERNET PAGE AT
WWW.WEATHER.GOV/LACROSSE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
HYDROLOGY...DAS/AJ
AREA FORECAST DISCUSSION
NWS TUCSON AZ
900 PM MST THU JUL 10 2014
.SYNOPSIS...STORM COVERAGE AND INTENSITY SHOULD INCREASE THIS
WEEKEND AS AN UPPER LEVEL DISTURBANCE APPROACHES THE AREA FROM THE
EAST. OTHERWISE...A CHANCE OF THUNDERSTORMS WILL CONTINUE INTO NEXT
WEEK. MOST STORMS WILL OCCUR DURING THE AFTERNOON AND EVENING HOURS
BUT SOME WILL LINGER OVERNIGHT. SOME STORMS WILL PRODUCE LOCALLY
HEAVY RAINFALL AND STRONG WINDS.
&&
.DISCUSSION...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ACROSS
GREENLEE/GRAHAM/COCHISE COUNTIES WITH DRY CONDITIONS ELSEWHERE AT
THIS TIME. A LARGE MCS ENCOMPASSED NEARLY THE ERN HALF OF SONORA
MEXICO...AND THIS CONVECTIVE ACTIVITY IS ASSOCIATED WITH DIFFLUENCE
ALOFT AS PER THE 11/00Z 300 MB UPPER AIR PLOT. CLOUD TOPS WERE
GENERALLY COOLING DURING THE PAST 1-2 HOURS ACROSS NERN SONORA.
11/01Z RUC HRRR AND TO SOME EXTENT THE 11/00Z NAM DEPICT AT LEAST
ISOLATED COVERAGE OF SHOWERS/TSTMS LATER TONIGHT MOSTLY EAST AND
SOUTH OF TUCSON. HAVE NOTED THAT THE 11/01Z RUC BRINGS PRECIP ECHOES
INTO TUCSON AROUND 11Z-12Z FRIDAY. THIS SOLUTION SEEMS PLAUSIBLE
ALBEIT PERHAPS SOMEWHAT SLOW GIVEN CURRENT RADAR/SATELLITE TRENDS.
THE OFFICIAL FORECAST DEPICTS DECREASING POPS ACROSS MUCH OF THE
AREA DURING THE NEXT FEW HOURS. HOWEVER...HAVE MAINTAINED A SLIGHT
CHANCE OF SHOWERS/TSTMS LATE TONIGHT FROM TUCSON EWD/SWD.
PRECIP-FREE CONDITIONS SHOULD OCCUR ACROSS WRN PIMA COUNTY. 11/00Z
NAM SUGGESTS THAT COVERAGE OF SHOWERS/TSTMS SHOULD INCREASE FRI
VERSUS THIS AFTERNOON/EVE. THE FAVORED AREA FOR SHOWERS/TSTMS FRI
AFTERNOON WILL BE EAST AND SOUTH OF TUCSON...WITH ISOLATED
SHOWERS/TSTMS TO OCCUR WEST-TO-NORTHWEST OF TUCSON. HIGH TEMPS FRI
WILL BE NEARLY IDENTICAL TO TEMPS ACHIEVED THIS AFTERNOON.
PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 12/06Z.
ISOLATED -TSRA/-SHRA MOSTLY EAST AND SOUTH OF KTUS THE REST OF
TONIGHT. THE BULK OF THESE SHOWERS/THUNDERSTORMS SHOULD END AROUND
DAYBREAK FRIDAY. EXPECT SCATTERED TSRA/SHRA FROM KTUS EASTWARD AND
SOUTHWARD FRIDAY AFTERNOON AND FRIDAY EVENING...WITH A LESSER CHANCE
OF SHOWERS/THUNDERSTORMS NORTHWEST OF KTUS. MVFR VISIBILITIES WILL
OCCUR WITH +TSRA...AS WELL AS WIND GUSTS MOSTLY AROUND 35-40 KTS.
OTHERWISE...CLOUD DECKS WILL BE AROUND 8-15K FT AGL. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...MOISTURE WILL REMAIN SUFFICIENT TO PROVIDE SCATTERED
TO PERHAPS NUMEROUS MAINLY AFTERNOON AND EVENING THUNDERSTORMS INTO
NEXT WEEK.
&&
.PREV DISCUSSION...WE SHOULD SEE A SIMILAR THREAT FOR SHOWERS AND
THUNDERSTORMS ON FRIDAY...BUT BY THIS WEEKEND AN EASTERLY WAVE
CURRENTLY OVER THE STATE OF COAHUILA MEXICO...WHICH IS JUST SOUTH OF
SOUTHWESTERN TEXAS...WILL MAKE ITS WAY THOUGH NORTHWEST MEXICO THIS
WEEKEND AND EARLY NEXT WEEK. THIS SYSTEM IS EXPECTED TO BRING AN
ENHANCED RISK FOR SHOWERS AND THUNDERSTORMS BEGINNING SATURDAY...BUT
ESPECIALLY SUNDAY INTO MONDAY. I INCREASED THE POP FORECAST AT BIT
FOR SATURDAY THROUGH MONDAY...BUT ESPECIALLY SATURDAY NIGHT AND
SUNDAY NIGHT FOR THE FAR WESTERN DESERTS NEAR AJO AND ORGAN PIPE FOR
THE POTENTIAL OF SEEING A THREAT FOR THUNDERSTORMS WELL INTO THE
NIGHT AS EASTERLY FLOW NORTH OF THE WAVE HELPS TO PUSH STORMS THAT
DEVELOP OVER EASTERN ZONES INTO THE LOWER DESERTS. ONCE THE EASTERLY
WAVE MOVES ACROSS NORTHERN BAJA AND THE NORTHERN GULF OF
CALIFORNIA...EXPECT CONVECTIVE ACTIVITY TO DROP DOWN TO ISOLATED
OVER THE WESTERN ZONES AND SCATTERED OVER THE EAST.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
PREV DISCUSSION...MOLLERE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1012 PM MDT THU JUL 10 2014
.UPDATE...
ISSUED AT 1012 PM MDT THU JUL 10 2014
A WIDE BAND OF SHOWERS AND T-STORMS STRETCHED FROM EAGLE COUNTY
IN WRN COLORADO TO WELL UP ACRS SERN SOUTH DAKOTA THIS EVENING AND
HAS PRETTY MUCH REMAINED IN THIS POSITION FOR MOST OF THE DAY.
OUR CWA HAS BEEN ON THE SOUTHERN FRINGE OF THIS BAND. HAVE SEEN
LITTLE TO NO LIGHTNING ON THE PLAINS TODAY DUE IN LARGE PART TO
MARGINAL INSTABILITY AND MINIMAL CAPES. HIGH COUNTRY SAW THE BULK
OF THE CONVECTION/T-STORM ACTIVITY TODAY AND EVEN THIS EVENING
WITH THE NEXT WAVE OF STORMS NOW PASSING OVER THE GORE...PARK AND
TEN MILE RANGES. SWLY FLOW ALOFT IS EXPECTED TO CARRY THESE
STORMS ACRS NORTHERN AND CENTRAL PORTIONS OF THE FRONT RANGE IN
THE NEXT COUPLE OF HOURS SOME WEAKENING ALONG THE WAY. MEANWHILE
ON THE PLAINS...THE RAP AN HRRR INDICATE A RESURGENCE IN
SHOWER/STORM FORMATION ALONG THE WY/NE BORDERS AND ACRS THE NERN
CORNER OF THE STATE DURING THE LATE EVENING/ERLY MORNING HOURS.
GOOD SHEAR AND MOISTURE /LOW-MID 60F DEWPTS/ NOW IN PLACE ACRS
NERN WELD...MORGAN...WASHINGTON...LOGAN...SEDGWICK AND PHILLIPS
COUNTIES COULD LEAD TO THE DVLPMNT OF SHOWERS/T-STORMS IN THIS
AREA IN NEXT COUPLE OF HRS. AT THIS TIME...NOTHING GOING ON OUT
THERE...BUT OUTFLOW BNDYS FROM NEBRASKA STORMS AND A COLD FRONT
DROPPING IN FROM THE NORTH SHOULD PROVIDE THE NEEDED LIFT TO
GENERATE THIS CONVECTION...POSSIBLY AS FAR WEST AS THE DENVER
METRO AREA. COULD SEE THE BEST CHANCE FOR PRECIP ACRS NERN
COLORADO TONIGHT IN THE NEXT 2-4 HOURS. MADE ADJUSTMENTS TO THE
EVENING FORECAST PACKAGE TO REFLECT ALL OF THIS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 329 PM MDT THU JUL 10 2014
STORMS HAVE FORMED OVER THE HIGHER TERRAIN DURING THE EARLY
AFTERNOON HOURS. WESTERLY FLOW ALOFT WILL PUSH SOME OF THE STORMS
OFF THE HIGHER TERRAIN. AIRMASS OVER THE FRONT RANGE URBAN CORRIDOR
IS DRY WITH DEW POINTS IN THE MID 30S TO MID 40S RESULTING IN A 50+
TEMPERATURE/DEW POINT SPREAD. THIS WILL MAKE IT DIFFICULT FOR STORMS
TO MAINTAIN OFF THE HIGHER TERRAIN...THOUGH A FEW WILL. RAINFALL
WILL MAINLY BE LIGHT BECAUSE OF THE DRY AIRMASS. BRIEF HEAVY RAIN
WILL BE POSSIBLE OVER THE HIGHER TERRAIN AND EASTERN PLAINS WHERE
THERE IS MORE MOISTURE.
THREAT FOR STORMS WILL DECREASE THIS EVENING. HOWEVER A COLD FRONT
WILL PUSH SOUTH TONIGHT AND INCREASE THE MOISTURE. BECAUSE OF
THIS...WILL KEEP LOW POPS IN THE FORECAST THROUGH THE NIGHT.
A MOIST AIRMASS WILL BE IN PLACE FRIDAY WITH PRECIPITABLE WATER
VALUES OF OVER AN INCH. DEW POINTS WILL BE IN THE 50S THROUGH THE
DAY. CAPES WILL BE HIGHER FRIDAY BECAUSE OF THE INCREASED
MOISTURE...POSSIBLY UP TO 1500 J/KG IF THE HIGHER DEW POINTS ON
THE GFS MODEL OCCURS. SHEAR WILL BE MARGINAL FOR SEVERE
STORMS...BUT MAY BE ENOUGH FOR A FEW SEVERE STORMS...MAINLY EAST.
HEAVY RAIN WILL LIKELY OCCUR WITH THE STRONGER STORMS. FORTUNATELY
WINDS ALOFT WILL BE 15 TO 25 KNOTS...SO STORMS SHOULD MOVE OFF TO
THE EAST ONCE THEY FORM. IF STORMS REFORM OR TRAIN OVER THE SAME
AREA...FLASH FLOODING WILL BE POSSIBLE.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 329 PM MDT THU JUL 10 2014
THUNDERSTORMS TO CONTINUE ACROSS THE AREA FRIDAY EVENING...MAINLY
ACROSS THE PLAINS AS BACK EDGE OF MID LEVEL TROUGH MOVES OVER THE
REGION. WITH PRECIPITABLE WATER VALUES OVER AN INCH ACROSS THE
PLAINS. LOCALLY HEAVY RAIN WILL BE POSSIBLE. IN ADDITION...WITH
CAPE VALUES OF AROUND 1000 J/KG EXPECTED FAR NORTHEAST CORNER SOME
HAIL CAN BE EXPECTED. LOOKS LIKE THERE WILL BE ENOUGH STORM MOTION
TO LIMIT THE THREAT FOR FLOODING. MOST STORMS TO END AROUND
MIDNIGHT AS SUBSIDENCE INCREASES.
ON SATURDAY...RIDGE RETROGRADES WITH FLOW BECOMING WESTERLY. STILL
A GOOD FETCH OF SUBTROPICAL MOISTURE ACROSS THE STATE WITH
PRECIPITABLE WATER VALUES OVER AN INCH ACROSS THE PLAINS. MID
LEVEL SHORTWAVE LOOKS TO MOVE SOUTHEAST ACROSS THE NORTHERN PLAINS
STATES DURING THE AFTERNOON WITH SOME MID LEVEL QG ASCENT ACROSS
NORTHEAST COLORADO. COMBINATION OF LIFT AND MOISTURE TO PROVIDE A
CHANCE OF THUNDERSTORMS MOST LOCATIONS DURING THE AFTERNOON.
MODELS GENERATE QPF ACROSS MUCH OF THE AREA...WITH THE GFS SHOWING
THE MOST. WITH SUFFICIENT MOISTURE AVAILABLE...STORMS COULD
PRODUCE LOCALLY HEAVY RAIN. APPEARS THERE IS ENOUGH STORM MOTION
TO KEEP THE STORMS MOVING...LIMITING THE FLASH FLOOD THREAT.
MODELS SHOW CAPE VALUES AROUND 1000-1500 J/KG NORTHEAST
PLAINS...SO HAIL ALSO A POSSIBILITY. COOLER AIRMASS OVER THE
AREA...WITH HIGHS IN THE MIDDLE 80S ACROSS THE PLAINS. FOR
SUNDAY...NORTHWEST FLOW ALOFT CONTINUES WITH UPPER RIDGE ACROSS
THE GREAT BASIN. CENTER OF THE HIGH LOOKS TO BE OVER EASTERN
NEVADA. WESTERLY FLOW ALOFT TO BRING SLIGHTLY DRIER AIR INTO
COLORADO...SHUNTING SOME OF THE SUBTROPICAL MOISTURE FEED SOUTH
AND EAST OF THE CFWA. STILL SUFFICIENT MOISTURE FOR A CHANCE OF
AFTERNOON AND EVENING THUNDERSTORMS MOST LOCATIONS...BUT MID LEVEL
SUBSIDENCE MAY LIMIT THE COVERAGE OF STORMS. STORMS COULD STILL
PRODUCE BRIEF HEAVY RAIN. LITTLE CHANGE IN TEMPERATURES EXPECTED
FROM SATURDAY...WITH HIGHS IN THE MIDDLE 80S OVER NORTHEAST
COLORADO. ON MONDAY...THE NORTHWEST FLOW ALOFT CONTINUES. MODELS
SHOW A MID LEVEL SHORTWAVE MOVING ACROSS CENTRAL PLAINS DURING THE
AFTERNOON WITH THE TAIL END INTO NORTHEAST COLORADO. WEAK FRONT
LOOKS TO PUSH INTO NORTHEAST PLAINS WITH SLIGHTLY COOLER AIR. BOTH
ECMWF AND GFS SHOW SUBTROPICAL MOISTURE PUSHING NORTHWARD AGAIN
WITH AN INCREASE IN PRECIPITABLE WATER. SHOULD SEE A CHANCE OF
AFTERNOON AND EVENING THUNDERSTORMS MOST LOCATIONS DUE TO THE LIFT
AND MOISTURE.
FOR THE LATER DAYS...TUESDAY THROUGH THURSDAY: MODELS SHOW
DEEPENING UPPER TROUGH ACROSS THE NORTHERN AND CENTRAL PLAINS
STATES TUESDAY AND WEDNESDAY WITH A MID LEVEL SHORTWAVE TROUGH
MOVING INTO NORTHEAST COLORADO TUESDAY AFTERNOON INTO WEDNESDAY.
SURFACE FRONT LOOKS TO PUSH INTO THE NORTHEAST PLAINS DURING THE
AFTERNOON. SUFFICIENT LIFT AND MOISTURE FOR A CHANCE OF MAINLY
AFTERNOON AND EVENING THUNDERSTORMS...BEST CHANCE EAST OF THE
CONTINENTAL DIVIDE. COOLER AIR TO SPILL INTO NORTHEAST COLORADO
BEHIND THE FRONT...WITH HIGHS EXPECTED TO ONLY BE IN THE MID AND
UPPER 70S ACROSS THE PLAINS. MODELS SHOW TROUGH MOVING INTO
SOUTHEAST COLORADO THURSDAY...WITH A DECREASING CHANCE FOR
THUNDERSTORMS. TEMPERATURES WARM SLIGHTLY BUT STILL BE A BIT
BELOW AVERAGE.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1012 PM MDT THU JUL 10 2014
PARTLY CLOUDY SKIES OVER THE METRO AREA AT PRESENT TIME WILL BECOME
MOSTLY CLOUDY TO OVERCAST SOON AFTER THE PASSAGE OF A COLD FRONT/
STRONG THUNDERSTORM OUTFLOW BOUNDARY FROM THE NORTH. THIS FRONTAL
BOUNDARY NOW RACING SOUTH THROUGH CENTRAL WELD COUNTY...SHOULD
ARRIVE IN THE DENVER AREA BY 0430Z...IF NOT SOONER. EXPECT GUSTY
NORTH-NORTHEAST WINDS TO AROUND 25KTS FOR ABOUT AN HOUR OR SO
AFTER ITS PASSAGE THEN EAST-NORTHEAST WINDS OF 7-13KTS FOR THE
REST OF THE NIGHT. ALSO LOOK FOR SKIES TO FILL WITH LOW AND MID-
LEVEL CLOUDS AND A 30-40 PCT CHANCE OF SHOWERS AND ISOLATED
T-STORMS THROUGH 08Z. COULD SEE CEILINGS LOWERING TO AROUND 5000
FT ALG...PARTICULARLY AT APA AND BJC AFTER MIDNIGHT. MOSTLY CLOUDY
SKIES ARE EXPECTED TO LINGER UNTIL AROUND SUNRISE THEN SKIES WILL
PARTIALLY CLEAR.
&&
.HYDROLOGY...
ISSUED AT 329 PM MDT THU JUL 10 2014
THREAT FOR FLASHING FLOODING TODAY WILL BE VERY LOW DUE TO A
DRY AIRMASS AND STORMS MOVING AROUND 15 MPH.
THE THREAT FOR FLASH FLOODING WILL INCREASE FRIDAY. AIRMASS WILL
BECOME MOIST. THE NUMBER OF THUNDERSTORMS IS ALSO EXPECTED TO
INCREASE WITH HEAVY RAIN ACCOMPANYING THE STRONGER STORMS. STORMS
WILL BE MOVING AROUND 10 TO 20 MPH ON FRIDAY. IF STORMS REFORM OR
TRAIN OVER THE SAME AREA FLASH FLOODING WILL BE POSSIBLE.
THUNDERSTORMS WILL BE POSSIBLE SATURDAY AND SUNDAY. AIRMASS TO
REMAIN FAIRLY MOIST SATURDAY WITH SOME DRYING SUNDAY. LOCALLY
HEAVY RAIN WILL BE POSSIBLE WITH SOME OF THE STORMS SATURDAY...BUT
STORMS SHOULD BE MOVING AROUND 15 TO 20 MPH...LIMITING THE FLASH
FLOOD THREAT. &&
.BOU WATCHES/WARNINGS/ADVISORIES...
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BAKER
SHORT TERM...MEIER
LONG TERM...D-L
AVIATION...BAKER
HYDROLOGY...MEIER
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
330 AM EDT FRI JUL 11 2014
.SYNOPSIS...
07Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING AN UNIMPRESSIVE UPPER
LEVEL PATTERN ACROSS THE CONUS. RIDGING OVER THE SOUTHERN
PLAINS/SOUTHWEST DIPS SLIGHTLY DOWNSTREAM INTO AN EASTERN CONUS
TROUGH. THIS TROUGH DROPS DOWN INTO THE SOUTHEAST CONUS BUT IS
REALLY ONLY ACTING TO BRIEFLY WEAKEN THE UPPER RIDGE THAT HAS BEEN
IN PLACE. THIS WEAKNESS WILL LINGER OVER THE NORTHERN PART OF THE
STATE THROUGH SATURDAY...BUT GENERALLY HAVE LITTLE OVERALL IMPACT ON
OUR SENSIBLE WEATHER. DEEP MOISTURE IS IN PLACE ACROSS THE PENINSULA
EARLY THIS MORNING...ALTHOUGH A SWATH OF DRIER AIR CAN BE SEEN
CLEARLY IN WV IMAGERY APPROACHING THE SE FLORIDA COAST. MODELS HAVE
BEEN STRUGGLING WITH THE STRENGTH OF THE DRIER AIR THAT WILL BE
ARRIVING WITH THIS FEATURE OVER PREVIOUS DAYS...BUT SEEM TO HAVE
COME TO A CONSENSUS THAT THE IMPACT TO OUR CONVECTIVE COVERAGE WILL
BE LIMITED AT BEST AS THE SWATH ROTATES INTO THE SOUTHERN PENINSULA
TODAY. WE WILL TALK MORE ABOUT ANY IMPACT FROM THIS DRY AIR TODAY IN
THE SHORT TERM DISCUSSION BELOW.
AT THE SURFACE...THE SUBTROPICAL RIDGE AXIS REMAINS ALIGNED OVER THE
CENTRAL PORTION OF THE STATE THIS MORNING. THE GRADIENT IS REALLY
LIGHT AND OUR CURRENT FLOW IS MOSTLY CONTROLLED BY THE DIURNAL LAND
BREEZE / SEA BREEZE CYCLES. LAND BREEZE IS RECENTLY BECOMING ACTIVE
ONCE AGAIN OVER THE COASTAL WATERS...WITH MORE AND MORE CONVECTIVE
ACTIVITY SHOWING UP ON REGIONAL RADARS. GENERALLY SPEAKING THIS
ACTIVITY SHOULD REMAIN JUST OFFSHORE THROUGH THE NEXT SEVERAL HOURS
AS THE BEST CONVERGENCE REMAINS OFFSHORE. ONLY EXCEPTION MIGHT BE UP
TOWARD CEDAR KEY AND CRYSTAL RIVER WHERE THE FLOW MAY ALLOW A BETTER
CHANCE FOR STORMS TO DEVELOP AT THE COAST...OR MIGRATE TO THE COAST
BEFORE SUNRISE. ELSEWHERE OVER LAND WE ARE SEEING A DRY AND
SEASONABLE MORNING UNDER SOME AREAS OF THIN HIGHER CLOUDS LEFTOVER
FROM THE CONVECTION ON THURSDAY.
&&
.SHORT TERM (TODAY AND TONIGHT)...
TODAY...FINAL DAY OF THE WORK WEEK IS UPON US. ARE WE LOOKING FOR
ANYTHING SPECIAL IN THE FORECAST TODAY? WELL...ACTUALLY NO. A VERY
TYPICAL SUMMER PATTERN REMAIN IN PLACE...AND THE ONE FEATURE (DRY
AIR ARRIVING ALOFT OVER THE SOUTHERN PART OF THE STATE) THAT LOOKED
EARLIER LIKE IT MIGHT RESULT IN REDUCED CONVECTION...NOW DOES NOT
APPEAR TO HAVE ENOUGH INFLUENCE TO REALLY IMPACT THE OVERALL
FORECAST. THE MAJORITY OF THE FORECAST AREA TODAY WILL ACTUALLY FIND
ITSELF UNDER A MOIST COLUMN WITH MID-LEVEL THETAE VALUES ABOVE CLIMO
AND PW VALUES APPROACHING OR EXCEEDING 2" (DEPENDING ON THE SELECTED
GUIDANCE). LOOKING AT A CROSS SECTION FROM NORTH TO SOUTH ACROSS THE
FORECAST AREA FOR THIS AFTERNOON...WE SEE EVEN DOWN TOWARD FORT
MYERS THE MINIMUM THETAE VALUES IN THE COLUMN ONLY DROP TO AROUND
325-328K. THIS IS NEAR NORMAL FOR THIS TIME OF YEAR...AND THE DEPTH
OF THIS "DRIER" ZONE IS NOT GREAT. MID-LEVEL TEMPERATURES (500MB OR
SO) ARE AROUND -8C TODAY. THESE VALUES ARE ALSO NEAR CLIMO AND
ALTHOUGH THEY WILL NOT OVERLY SUPPORT NUMEROUS STRONG UPDRAFTS IN
THE HAIL GROWTH ZONE...THEY SHOULD NOT SUPPRESS UPDRAFTS EITHER.
WITH ALL THIS IN MIND...THE DEEP MOISTURE OVER MUCH OF THE AREA TIPS
THE SCALES IN FAVOR OF AN ATMOSPHERE THAT IS SUPPORTIVE OF DEEP
CONVECTION.
NOW...MUCH OF THE TIME WE ARE DIAGNOSING THE POSITION OF THE
SUBTROPICAL RIDGE AXIS TO DETERMINE THE MEAN 1000-700MB FLOW AND
WHERE THIS SYNOPTIC FLOW WILL INTERACT WITH THE SEA-BREEZE TO MOST
FOCUS LIFT FOR STORMS. TODAY THE RIDGE AXIS IS OVER THE CENTRAL TO
NORTH-CENTRAL PORTIONS OF THE PENINSULA AND IS RATHER WEAK. THIS
POSITION AND FORM LEAVES MOST OF THE AREA IN A RATHER VARIABLE FLOW
PATTERN...AND EVEN THE SOUTHEAST FLOW DOWN TOWARD FORT MYERS IS ONLY
A FEW KNOTS. THEREFORE...THE NORMAL SPATIAL AND TEMPORAL PATTERNS OF
DEFINED REGIMES GO "OUT THE WINDOW" TODAY. EVEN WHERE WE DO HAVE A
MEASURABLE DIRECTION TO THE FLOW (SYNOPTIC OR SEA-BREEZE)...IT IS
WEAK ENOUGH THAT ANY THUNDERSTORM OUTFLOW WILL EASILY OVERWHELM IT.
ON THESE TYPES OF DAYS...STORMS MAY DEVELOP NEAR THE COAST AND MOVE
INLAND...ONLY TO COME BACK TOWARD THE COAST LATER IN THE DAY WITH
THE OUTFLOW FROM SECOND/THIRD/OR FOURTH GENERATION STORMS. THEREFORE
WILL NOT GET TOO DETAILED WITH THE POP GRIDS...BUT SHOW ABOVE CLIMO
COVERAGE (50-65%) THROUGH THE AFTERNOON/EVENING. THIS IS A GOOD
"MIDDLE OF THE ROAD" RANGE FOR MOST PLACES GIVEN THE UNDEFINED
PATTERN...BUT FAVORABLE THERMODYNAMICS. CERTAINLY SOME REGIONS WILL
SEE HIGHER COVERAGE...BUT IT WOULD BE JUST A GUESS TO TRY AND
PINPOINT EXACTLY WHERE. WILL LET THE NEXT SHIFT EVALUATE THE
CONVECTIVE PATTERN EARLY IN THE PROCESS LATER THIS MORNING AND
UPDATE AS NECESSARY.
OTHERWISE...OUTSIDE THE STORMS WE SHOULD SEE A WARM AND MUGGY JULY
DAY. TEMPERATURES WHERE THE STORMS HOLD OFF LONG ENOUGH WILL GET UP
TO WITHIN A DEGREE OR 2 OF 90. WEAK OFFSHORE FLOW THIS MORNING AT
THE BEACHES WILL SHIFT TO WEAK ONSHORE AFTER 1-2 PM.
TONIGHT...
EVENING SHOWERS AND STORMS WILL TAPER OFF WITH SUNSET AND THE LOSS
OF DIURNAL HEATING. LAND BREEZE CONVERGENCE WILL THEN RAMP SCT
CONVECTION BACK UP OVER THE COASTAL WATERS DURING THE SECOND HALF OF
THE NIGHT...AND INTO EARLY SATURDAY MORNING. GENERALLY SPEAKING WILL
BE LOOKING FOR A DRY FORECAST OVER MUCH OF THE LAND MASS AFTER 10-11
PM. LOW TEMPERATURES LOOK SEASONABLE WITH LOWER 70S INLAND AND
MIDDLE TO UPPER 70S NEAR THE COAST. HAVE A GREAT FRIDAY AND ENJOY
YOUR WEEKEND!
&&
.MID TERM (SATURDAY AND SUNDAY)...
THE SOUTHERN END OF AN EASTERN CONUS UPPER LEVEL TROUGH ACROSS
NORTH FL SAT LIFTS NORTHEASTWARD SAT NIGHT AND SUN AS UPPER LEVEL
RIDGING BUILDS IN ACROSS THE STATE. ATLANTIC HIGH PRESSURE RIDGES
WEST AS IT REMAINS IN THE VICINITY OF LATITUDE 30. THERE WILL BE
ENOUGH MOISTURE FOR ISOLATED BECOMING SCATTERED THUNDERSTORMS...
WITH THE HIGHEST ODDS INLAND IN THE AFTERNOONS. HOWEVER EXPECT SOME
COASTAL SHOWERS/STORMS IN THE EVENING AND MORNING HOURS.
TEMPERATURES RUN NEAR NORMAL.
&&
.LONG TERM (MONDAY THROUGH NEXT THURSDAY)...
UPPER RIDGING INITIALLY ACROSS FL FROM THE GULF TO THE ATLANTIC
SHIFTS SOUTHWARD DURING EARLY TO MID WEEK AS A RATHER ROBUST LOW
SWINGS DOWN OUT OF WESTERN CANADA AND THROUGH THE MIDWEST AND GREAT
LAKES BEFORE LIFTING BACK INTO QUEBEC. THE SURFACE RIDGE AXIS SLOWLY
TRAVERSES DOWN THE STATE...REACHING NORTHERN CUBAN COASTAL WATERS BY
THE END OF THE PERIOD. THE ATMOSPHERE CONTINUES MOIST WITH ISOLATED
TO SCATTERED SHOWERS AND STORMS. AS THE PREVAILING FLOW BECOMES
SOUTHWEST AND WESTERLY EXPECT MORE MORNING COASTAL SHOWERS THAT
INCREASE TO SCATTERED STORMS INLAND IN THE AFTERNOON.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST FLORIDA
EARLY THIS MORNING. CONVECTION JUST OFFSHORE WILL LIKELY BE VISIBLE
FROM THE NEAR SHORE TERMINALS...BUT DO NOT EXPECT ANY OF THESE CELLS
TO MIGRATE ONSHORE TO IMPACT ANY TERMINALS UNTIL AT EARLIEST MID
MORNING. A GOOD COVERAGE OF SHOWERS AND STORMS EXPECTED FOR THE
AFTERNOON AND EARLY EVENING HOURS. WEAK FLOW WILL MAKE TIMING STORMS
FOR ANY PARTICULAR TERMINAL DIFFICULT...BUT ANTICIPATE OFF AND ON
STORMS IN THE VICINITY OF THE TERMINALS AFTER 18Z.
&&
.MARINE...
THE SUBTROPICAL RIDGE AXIS REMAIN IN PLACE ACROSS THE FLORIDA
PENINSULA AND EASTERN GULF THE NEXT SEVERAL DAYS. A LIGHT GRADIENT
PROVIDES LOW WINDS AND SEAS THROUGH THE WEEKEND...OUTSIDE OF
SCATTERED THUNDERSTORMS. THUNDERSTORMS OVER THE WATER SHOULD BE MOST
NUMEROUS DURING THE LATE NIGHT AND EARLY MORNING HOURS.
&&
.FIRE WEATHER...
NO SIGNIFICANT FIRE WEATHER CONCERNS EXPECTED THROUGH THE UPCOMING
WEEKEND AS RELATIVE HUMIDITY VALUES REMAINS WELL ABOVE CRITICAL
LEVELS. THUNDERSTORMS LOOK TO BE QUITE NUMEROUS IN NATURE LATER THIS
AFTERNOON AND EARLY EVENING WITH LOCALLY HEAVY RAINFALL POSSIBLE.
WEAK TRANSPORT WINDS THE NEXT COUPLE OF DAYS SHOULD HELP KEEP
DISPERSION LEVELS RATHER LOW AS WELL. NO SIGNIFICANT FOG IS
EXPECTED...ALTHOUGH SOME PATCHY GROUND FOG IS POSSIBLE EACH NIGHT IN
LOCALIZED SPOTS THAT RECEIVE SIGNIFICANT LATE DAY RAINFALL.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 90 76 91 77 / 60 40 40 20
FMY 92 74 93 76 / 60 20 50 20
GIF 91 74 92 75 / 60 40 40 10
SRQ 89 75 91 75 / 50 40 30 20
BKV 91 72 92 73 / 50 40 40 20
SPG 90 78 90 79 / 50 40 40 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
MID TERM/LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1100 PM MDT Thu Jul 10 2014
.DISCUSSION...
Update forthcoming. Lingering monsoonal moisture, along with
atmospheric instability along the southwest Montana/Idaho border, is
allowing isolated thunderstorms to continue. However, the moisture
source is beginning to decrease and convective activity should
further decrease with the loss of daytime heating. Have scaled back
the POP field through midnight, keeping POPs over extreme south and
southeast Montana. Have scaled back POPs even further after
midnight. In the north, circulation around an upper low centered
over western Saskatchewan is pushing moisture into an unstable
airmass and across the Canadian prairie. This moisture has combined
with a cold front moving south and the result is the development of
isolated thunderstorms. Satellite imagery indicates a strong
thunderstorm moving east-southeast across southern Alberta at this
time. RUC model data and HRRR analysis want to bring the core of
this storm south of the international border after 05z, affecting
areas along the Hi-Line. Have gone with low POPs across the northern
portion of the county warning area for this reason, bringing the
threat as far south as Lewistown and as far west as Great Falls per
the RUC. Temperatures look reasonable.
&&
.AVIATION...
UPDATED 0500Z.
VFR conditions will generally continue across the area through at
least Friday evening. Moisture wrapping around a low pressure system
in central Canada combined with a weak cold front moving south
through north central/central Montana area has caused scattered
thunderstorms to develop across north central Montana (including
KCTB KHVR). These storms will likely weaken as they spread south
into central (KGTF KLWT) Montana through, so have only mentioned
VCSH in those TAFs at this time. Clouds/showers/storms will decrease
after 15Z as the system exits the area. However, monsoonal moisture
will move back into southwest Montana (including KBZN) after 18Z,
bringing a chance of thunderstorms there.
Coulston
&&
.PREV DISCUSSION...Issued 242 PM MDT Thu Jul 10 2014
Thursday through Saturday...Hot and dry conditions will continue
as the slowly moving large scale ridge continues to be dominant
force in the weather pattern over much of the Western United States.
Will continue to remain in a transition period on the edge of the
ridge through at least the next 24 hours. This will allow for
showers to develop as moisture allows. The best chance will be
with afternoon heating over the Mountains of Southwest Montana and
across the highline Thursday Evening as a weak disturbance moves
across the northern counties. By Friday a slight increase in
available moisture will allow for more showers and thunderstorms
to develop with afternoon heating...however showers will likely be
limited to scattered at best coverage. Another round of showers
will again occur on Saturday during peak heating mainly over the
higher terrain. Suk
Saturday night through Thursday...An upper level ridge high
pressure will be over the region this weekend...then the upper level
ridge will shift westward on Monday...as a fairly strong upper level
low pressure over the Great Lakes area rotates a bit cooler air into
the region. As the upper level low over the Great Lakes begins to
move eastward on Tuesday...the upper level ridge will also start to
shift back eastward for Tuesday afternoon through Thursday. Thus
fairly warm temperatures are expected for Sunday...then seasonable
temperatures for Monday and Tuesday...with a return to slightly
above normal temperatures for Wednesday and Thursday. In terms of
precipitation...confidence is quite low on any one given day...thus
most days the chances for thunderstorms are fairly isolated. The
best time frame for any storms to occur will be late afternoon
through around Midnight...but again the thunderstorm activity should
be fairly isolated and not have significant impacts on any one given
day. Brusda
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 54 78 54 86 / 20 10 10 10
CTB 51 75 50 84 / 20 10 10 10
HLN 58 84 58 88 / 10 10 20 20
BZN 53 83 54 83 / 10 30 20 40
WEY 44 79 44 76 / 30 50 40 50
DLN 54 84 55 83 / 10 20 20 40
HVR 56 80 53 88 / 20 20 10 10
LWT 54 78 53 84 / 20 20 20 20
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
www.twitter.com/NWSGreatFalls
www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS RALEIGH NC
145 AM EDT FRI JUL 11 2014
.SYNOPSIS...A WEAKENING SURFACE BOUNDARY WILL DRIFT TOWARD THE COAST
TODAY. WEAK HIGH PRESSURE WILL SETTLE OVER THE REGION SATURDAY AND
SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 1000 PM THURSDAY...
AFTERNOON AND EARLY EVENING CONVECTION HAS STABILIZED MOST AREAS EAST
OF US HWY 1...WHILE SPC MESOANALYSIS AND RAP SOUNDINGS SHOW AROUND
500 J/KG MLCAPE AND LESS THAN ONLY 100 J/KG MLCINH OVER THE WESTERN
PIEDMONT. THE UPPER TROUGH AND ASSOCIATED VORTICITY MAX ARE STILL
TO THE WEST...APPROACHING THE APPALACHIANS THIS EVENING. THE
PRIMARY COLD FRONT IS ALSO JUST WEST OF OR BEGINNING TO CROSS THE
MOUNTAINS...WITH A SHARP TROUGH IN THE LESS OF THE MOUNTAINS.
BLENDED TPW SHOW PW STILL WELL ABOVE 1.5 INCHES. RADAR TRENDS HAVE
BEEN DOWNWARD TO JUST A COUPLE ISOLATED SHOWERS OVER DAVIDSON AND
RANDOLPH/CHATHAM COUNTIES....AND THE HRRR SHOWS VERY LITTLE QPF
AFTER MIDNIGHT. THERE MAY STILL BE A FEW SHOWERS OR AN ISOLATED
STORM GIVEN THE AFOREMENTIONED FORCING...ESPECIALLY WITH THE UPPER
VORT MAX AND PRIMARY COLD FRONT. WILL LOWER POPS A BIT
AREAWIDE...WHILE KEEPING A SLIGHT CHANCE WEST AND CHANCE EAST. ALSO
ADDING PATCHY FOG GIVEN THE WIDESPREAD RAIN AND PARTIAL CLEARING
AHEAD OF THE FRONT. -BLS
FOR FRI/FRI NIGHT: AS THE DAMPENING SHEAR AXIS SHIFTS TO OUR SE IN
LINE WITH THE DISSIPATING SURFACE TROUGH... THE HIGHER PW VALUES
WILL ACCORDINGLY SHIFT TO THE COASTAL PLAIN... LEAVING A LIGHT NNE
LOW LEVEL FLOW AND RELATIVELY (FOR JULY) DRY COLUMN OVER THE NRN AND
WRN CWA. MODELS GENERALLY INDICATE VERY LITTLE PRECIP COVERAGE...
CONFINING AFTERNOON CONVECTION TO THE COASTAL PLAIN AND SE SANDHILLS
WHERE MODELS PROJECT MUCAPE PEAKING AT 1000-1500 J/KG. WILL RETAIN
CHANCE POPS HERE WITH ISOLATED CHANCES TO THE NW. A DIP IN
THICKNESSES TO SLIGHTLY BELOW NORMAL VALUES SUPPORTS HIGHS OF 85-90.
EXPECT LITTLE MORE THAN PATCHY SHOWERS FRI NIGHT. LOWS 66-71. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 315 PM THURSDAY...
THE MID LEVEL TROUGH AXIS (CURRENTLY MOVING TOWARDS THE AREA) WILL
PUSH OFFSHORE ON SATURDAY...WHILE THE MID LEVEL RIDGE TRIES TO BUILD
EASTWARD TOWARDS THE REGION. MODELS HAVE TRENDED DRIER FOR THE
WEEKEND...ESPECIALLY ON SATURDAY GIVEN THE DRIER AIR FILTERING INTO
THE REGION BEHIND THE DEPARTING TROUGH. IN FACT...FORECAST SOUNDINGS
INDICATE VERY LIMITED DEEP LAYER MOISTURE...WITH PWAT VALUES PROGGED
TO RANGE BETWEEN 1-1.25 INCHES (WELL BELOW NORMAL). THEREFORE...
WILL GO WITH A MOSTLY DRY FORECAST FOR SATURDAY. MOISTURE WILL START
TO RECOVER SOME ON SUNDAY AND A SURFACE TROUGH WILL SHARPEN UP OVER
THE REGION...LEADING TO A BETTER CHANCE OF MOSTLY DIURNAL TYPE
STORMS...ALTHOUGH OVERALL COVERAGE SHOULD STILL BE RATHER LOW. LOW
LEVEL THICKNESS VALUES ARE PROGGED TO BE NEAR 1420M ON SATURDAY AND
GIVEN EXPECTED LACK OF PRECIP...TEMPS SHOULD RISE INTO THE UPPER 80S
TO LOWER 90S. BY SUNDAY...LOW LEVEL THICKNESS VALUES ARE EXPECTED TO
CLIMB ANOTHER 5-10M...RESULTING HIGH TEMPS A FEW DEGREES
WARMER...GENERALLY LOW TO MID 90S (ALTHOUGH MORE CLOUDS MAY BE
AROUND WHICH WOULD TEMPER THE WARMING SOME).
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 315 PM THURSDAY...
A DEEP VORTEX IS PROGGED TO MOVE SOUTH OUT OF CANADA AND EVENTUALLY
ACROSS THE GREAT LAKES THROUGH THE MIDDLE OF NEXT WEEK. THIS WILL
RESULT IN A DEEP TROUGH DEVELOPING OVER THE EASTERN HALF OF THE
CONUS. THEREFORE...PRECIP CHANCES WILL BE ON THE INCREASE FOR NEXT
WEEK...ESPECIALLY LATE TUESDAY INTO EARLY WEDNESDAY AS A FRONT
APPROACHES THE AREA. ALSO...GIVEN THIS UNSEASONABLY STRONG TROUGH...
THE MID LEVEL FLOW IS EXPECTED TO STRENGTHEN AND THEREFORE THE
POSSIBILITY OF AN ORGANIZED SEVERE THREAT WILL EXIST AND THIS WILL BE
MONITORED OVER THE NEXT SEVERAL DAYS. THEN THERE IS STILL A GOOD BIT
OF UNCERTAINTY WITH REGARDS TO IF THIS FRONT WILL PUSH ALL THE WAY
THROUGH THE AREA...BUT FOR NOW IT LOOKS LIKE THE FRONT WILL STALL
SOMEWHERE ACROSS THE CAROLINAS. THUS...WILL SHOW A LITTLE DECREASE
IN POPS FOR THE LATTER HALF OF THE WEEK...BUT WILL KEEP A CHANCE IN
GIVEN THE UNCERTAINTY WITH REGARDS TO WHERE THE FRONT ENDS UP. HIGH
TEMPS AHEAD OF THE FRONT ARE EXPECTED TO BE IN THE LOW TO MID 90S ON
MONDAY AND POSSIBLY TUESDAY...ALTHOUGH DEPENDING ON THE TIMING OF
THE PRECIP...TEMPS COULD BE SLIGHTLY LOWER ON TUESDAY. THEN SLIGHTLY
COOLER TEMPS ARE EXPECTED WEDNESDAY AND THURSDAY GIVEN THE DEEP
TROUGHING OVER THE EAST COAST AND THE POSSIBILITY THAT THE FRONT
WILL PUSH THROUGH THE AREA.
&&
AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 145 AM FRIDAY...
A NEARLY SATURATED LOW LEVEL AIR MASS WILL SUPPORT THE DEVELOPMENT
OF WIDESPREAD FOG AND LOW CLOUDS OVERNIGHT...AND INTO THE FIRST HALF
OF THIS MORNING. THIS SHOULD LEAD TO WIDESPREAD IFR/LIFR
CONDITIONS. IN ADDITION...COULD SEE A FEW SHOWERS DEVELOP ALONG A
SLOW MOVING SURFACE FRONT OVER THE SANDHILLS AND COASTAL PLAIN
OVERNIGHT INTO THE MID MORNING HOURS.
BETWEEN 14Z AND 16Z...SHOULD SEE VISIBILITIES AND CEILINGS IMPROVE
THOUGH STILL EXPECT MVFR CEILINGS TO OCCUR AT ALL TAF SITES.
AFTER 16Z...AS DRIER AIR BECOMES MORE ESTABLISHED OVER THE WESTERN
AND NORTHERN PIEDMONT...SHOULD SEE MVFR CEILINGS LIFT INTO A
SCATTERED STRATOCUMULUS FIELD WITH BASES 2000-3000FT.
ELSEWHERE...MVFR CEILINGS WILL PERSIST WITH CEILINGS 1500-2800FT
EXPECTED. IN ADDITION WILL SEE AN INCREASE IN SHOWER AND
THUNDERSTORM COVERAGE OVER THE COASTAL PLAIN THOUGH EXPECT MOST OF
THE ACTIVITY TO OCCUR TO THE EAST-SE OF KFAY AND KRWI.
FRIDAY NIGHT THROUGH SUNDAY...A WEAK AREA OF HIGH PRESSURE WILL
BUILD THEN SETTLE INTO THE REGION. THIS WEATHER SYSTEM SHOULD
MAINTAIN VFR CONDITIONS ACROSS CENTRAL NC.
THE WEATHER PATTERN WILL GRADUALLY BECOME UNSETTLED EARLY NEXT WEEK
AS A LOW PRESSURE SYSTEM APPROACHES FROM THE NORTHWEST. THIS SHOULD
LEAD TO AN INCREASE IN LOW AND MID LEVEL MOISTURE...RESULTING IN
EARLY MORNING FOG AND LOW CLOUDS. ALSO...EXPECT PERIODS OF MVFR
CEILINGS AND VISIBILITY DUE TO SHOWERS AND THUNDERSTORMS IN THE
AFTERNOON...ESPECIALLY TUESDAY AFTERNOON INTO TUESDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...HARTFIELD/BLS
SHORT TERM...KRD
LONG TERM...KRD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
437 AM EDT FRI JUL 11 2014
.SYNOPSIS...
THE UPPER AIR FLOW WILL BECOME WESTERLY THIS WEEKEND. TEMPERATURES
WILL BE SEASONABLE TODAY BUT BECOME HOTTER ON SATURDAY AND
SUNDAY. DESPITE THE INFLUENCE OF HIGH PRESSURE AT THE
SURFACE...THE AREA WILL REMAIN VULNERABLE FOR ISOLATED SHOWERS AND
THUNDERSTORMS TO POP UP EACH AFTERNOON OFF THE HIGH TERRAIN.
HIGHER CHANCES OF STORMS ARE EXPECTED MONDAY AND TUESDAY AS A
VERY STRONG TROUGH OF POLAR AIR WILL PUSH SOUTHWARD INTO THE GREAT
LAKES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOG BEGINNING TO SHOW IT/S HAND...DEVELOPING IN THE COOL SINKS
WHERE THE RAINFALL OCCURRED YESTERDAY. VISBYS WILL GRADUALLY
DECLINE IN MANY SPOTS ACROSS THE SRN HALF OF THE REGION...WHERE
THE AMBIENT MOISTURE IS HIGHEST. THE FOG WILL BURN OFF BY 9 AM AS
THE ATMOS MIXES QUICKLY UNDER OTHERWISE SUNNY SKIES. THE VERY DRY
/FOR JULY/ DEWPOINTS NEAR 50F IN THE NORTHERN TIER WILL MOST
LIKELY RISE A BIT THIS MORNING. THE PATTERN OF CONVECTIVE CLOUDS
POPPING UP LATE MORNING OVER THE HIGH TERRAIN OF THE ALLEGHENIES
WILL HAPPEN ONCE AGAIN TODAY. A SUBTLE SHORT WAVE FEATURE OVER THE
NORTHWEST THIS MORNING WILL SLIDE EAST AND WILL LIKELY CAUSE THE
SHORT CU TO GROW BIGGER AND PRODUCE ISOLD T/SHRA IN THE AFTN. IT
MAY ALSO HELP SOME SHRA GROW IN THE SERN PART OF THE AREA - AGAIN
MAINLY OFF THE ELEVATED HEATING SURFACES - AND DRIFT EASTWARD.
TEMPS WILL PROBABLY BE A LITTLE MORE HOMOGENOUS TODAY- THE DRIER
AIR OVER THE NW WILL BE HEATED EASILY BY THE JULY SUN...AND MORE
CLOUDS OVER THE SE IN MID-DAY/AFTN WILL CUT A DEG OR TWO OFF
YESTERDAY/S MAXES THERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
AFTN CONVECTION WILL WANE VERY QUICKLY AS WE WILL BE IN THE
UNFAVORABLE WAKE/HEIGHT BUMP/SUBSIDENCE OF A WEAK SHORT WAVE.
WILL CHOP THE POPS OFF AFTER SUNSET...BUT IT MAY HAPPEN EARLIER.
MINS TONIGHT WILL BE SIMILAR TO THIS MORNING. SATURDAY LOOKS LIKE
THERE COULD STILL BE A FEW SHRA AROUND. WILL KEEP ON WITH THE
IDEA OF TERRAIN INDUCED SHRA. NO BIG CHANGES TO THE AIRMASS...NOR
TO THE UPPER PATTERN/TEMPS THROUGH THE SHORT TERM. BUT THE SFC
HIGH DOES SLIDE TO THE SHORE AND ALLOW MORE SOUTHERLY WINDS.
THUS...TEMPS SHOULD GET HOTTER FOR SAT. U80S ARE EXPECTED IN THE
EASTERN VALLEYS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
STALLED FRONT ALONG THE SOUTHEAST COAST SHOULD PIVOT BACK NWD AS
WARM FRONT SAT NGT INTO EARLY SUNDAY WITH S-SWLY LLJ INC LLVL MSTR
FLUX THRU THE UPPER OH VLY INTO WRN PA IN ADVANCE OF LEAD
SHORTWAVE ENERGY AND ASSOCD SFC COLD FRONT MOVG SEWD ACRS THE GRT
LKS-MIDWEST.
AMPLIFICATION OF THE UPPER PATTERN BEGINS EARLY NEXT WEEK WITH A
MODEL CONSENSUS GENERALLY INDICATING A FRONTAL PCPN AXIS SHIFTING
SEWD THRU THE GRT LKS/OH VLY REGIONS INTO CENTRAL PA SUN-MON.
ALTHOUGH PREDICTABILITY IS TOO LOW ATTM...A SEVERE WX THREAT
SHOULD SPREAD SEWD IN TIME FROM THE UPPER MIDWEST/GRT LKS/OH VLY
INTO THE MID ATLC AND NORTHEAST STATES...ALONG SRN PERIPHERY OF
STRONGER WINDS/CYC FLOW ALOFT AND SEVERAL REINFORCING COLD
FRONTAL SURGES ASSOCIATED WITH THE AMPLIFYING SYNOPTIC UPPER
TROUGH. EACH COLD FRONTAL SURGE WILL PROVIDE AN OPPORTUNITY FOR
SHOWERS/TSTMS THROUGH AT LEAST TUESDAY.
THE HIGHLY ANOMALOUS AMPLIFICATION OF THE LARGE SCALE PATTERN IS
A VIRTUAL LOCK BY THE END OF THE PERIOD AS INDICATED BY ALL MEDIUM
RANGE GLOBAL NUMERICAL MODELS AND ENSEMBLE SYSTEMS. THIS WELL-
ADVERTISED HIGH MERIDIONAL EVENT WILL FEATURE A FULL-LATITUDE
RIDGE AND SEARING HEAT OUT WEST...NOT BE BE OUTDONE BY THE RETURN
OF THE POLAR VORTEX IN THE EAST OVER QUE/ONT AND THE UPPER GREAT
LAKES. CONSIDERING THE MAGNITUDE OF THE UPPER LEVEL TROUGH WITH
500MB STANDARDIZED ANOMALIES ON THE ORDER OF -3 TO -4SD IN BOTH
THE DETERMINISTIC GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLE
MEANS...CONFIDENCE IN A PERIOD OF BELOW AVG TEMPS /DURING WHAT IS
CLIMATOLOGICALLY THE HOTTEST TIME OF THE YEAR/ IS VERY HIGH FROM
TUE-THU OF NEXT WEEK.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
MCLEAR SKIES AND LIGHT WIND WILL PROMOTE AREAS OF FOG EARLY THIS
MORNING ACROSS SOUTHERN PA...WHERE THE GROUND REMAINS WET FROM RAIN
LAST EVENING. A COMBINATION OF 05Z DWPT DEPRESSIONS...SREF AND
LATEST RAP OUTPUT ALL SUGGEST IFR VSBYS AT KAOO AND KLNS ARE VERY
LIKELY EARLY THIS AM AND POSSIBLE AT KUNV AND KMDT. FURTHER
NORTH...CAN/T RULE OUT SOME FOG TOWARD DAYBREAK AT KBFD AND KIPT.
HOWEVER...THIS AREA MISSED THE RAINFALL FROM LAST EVENING AND
LATEST RAP SUGGESTS DRIER AIR POISED ACROSS NY STATE WILL WORK
INTO NORTHERN PA ON NORTHERLY BREEZE EARLY THIS AM...MINIMIZING
THE FOG THREAT.
ANY EARLY FOG SHOULD BURN OFF BY ARND 12Z. WITH HIGH PRESSURE
OVER THE AREA...THERE IS A HIGH CONFIDENCE IN WIDESPREAD VFR
CONDS AND LGT WIND THE REST OF TODAY.
OUTLOOK...
SAT...NO SIG WX EXPECTED.
SUN-TUE...BRIEF...MAINLY PM...THUNDERSTORM IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1229 AM CDT FRI JUL 11 2014
.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
SHORT WAVE TROUGH CLOUD COVER AND SCATTERED LIGHT SHOWERS HAVE
LESSENED THE BUILDUP OF INSTABILITY ACROSS THE REGION LATE THIS
AFTERNOON. THE SPC ANALYSIS SHOWED ONLY 500 TO 1500 J/KG OF MIXED
LAYER CAPE FROM NORTH TO SOUTH ACROSS THE CWA LATE THIS AFTERNOON.
ALTHOUGH...THE DEEP LAYER SHEAR WAS IMPRESSIVE UP TO OVER 50
KNOTS. EXPECT SOME MORE BUILDUP OF INSTABILITY INTO THE EVENING
ACROSS THE CWA AS CLOUDS AND LIGHT SHOWERS MOVE EAST. THE GFS AND
HI-RES MODELS STILL SHOWING NUMEROUS SHOWERS/STORMS DEVELOPING
MAINLY ACROSS THE EASTERN CWA THIS EVENING. CENTRAL SD ALSO SEEING
MORE SUNSHINE AND WARMING LATE THIS AFTERNOON. WITH AN INCREASING
85H LLJ ACROSS MAINLY THE EAST THIS EVENING...EXPECT A GOOD CHANCE
OF SHOWERS/STORMS ACROSS THIS REGION. INCREASED POPS THIS EVENING.
THE MODELS THEN SHOW A WEAK BOUNDARY DROPPING SLOWLY SOUTHEAST
TONIGHT AND FRIDAY BRINGING WINDS AROUND TO THE EAST AND NORTHEAST
ACROSS MOST OF THE CWA. AFTER THE CONVECTION TONIGHT...EXPECT MOST
OF FRIDAY TO NOW BE DRY ACROSS THE CWA. THE MODELS THEN SHOW
ANOTHER SHORT WAVE TROUGH FROM THE NORTHWEST DROPPING ACROSS THE
CWA FRIDAY NIGHT AND SATURDAY ALONG WITH A GOOD JET STREAK
DEVELOPING TO OUR NORTH AND NORTHEAST. THIS WILL PUT US IN THE
FAVORABLE RR QUADRANT. THUS...HAVE IN CHANCES OF MAINLY ELEVATED
SHOWERS/STORMS FOR FRIDAY NIGHT AND SATURDAY WITH EVERYTHING
MOVING OFF TO THE SOUTHEAST SATURDAY NIGHT. HIGHS WILL BE IN THE
80S ON FRIDAY AND A FEW DEGREES COOLER ON SATURDAY.
.LONG TERM...SUNDAY THROUGH THURSDAY
SUNDAY SHOULD PROVE TO BE THE WARMEST DAY OF THE EXTENDED FORECAST
PERIOD...WITH ANOMALOUSLY COOL AIR ADVECTING DOWN INTO THE CWA
MONDAY AND STICKING AROUND THROUGH PROBABLY WEDNESDAY...AT LEAST.
THIS SHOULD SPELL SOME MUCH BELOW NORMAL TEMPERATURES THROUGHOUT
THE PERIOD AND DRY CONDITIONS THROUGHOUT THE PERIOD. COLD AIR
INSTABILITY CU/STRATO-CU WILL LIKELY ONLY ADD INSULT TO INJURY ON
MONDAY CLOUDING THINGS UP AND KEEPING JULY INSOLATION FROM TAKING
THE EDGE OFF THE COLDNESS OF THE AIR ON MONDAY.
&&
.CLIMATOLOGICALLY...
AN ANOMALOUSLY COLD LOW PRESSURE SYSTEM WILL MOVE INTO UPPER
MIDWEST EARLY NEXT WEEK. THE COMBINATION OF A COOL CANADIAN
AIRMASS ALONG WITH INCREASING CLOUDS AND A CHANCE FOR SHOWERS
COULD RESULT IN A FEW RECORD LOW HIGH TEMPERATURES ON MONDAY.
BELOW IS A LIST OF LOCATIONS THAT COULD SEE NEAR RECORD COLD
READINGS ON MONDAY:
...LOCATION......FORECAST....RECORD LOW HIGH TEMP...
WHEATON MN 64 72 IN 1949
SISSETON 65 70 IN 1993
WATERTOWN 65 61 IN 1962
ABERDEEN 67 65 IN 1962
MOBRIDGE 69 64 IN 1962
PIERRE 72 65 IN 1989
&&
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
THUNDERSTORMS CONTINUE TO BE A THREAT THROUGH THE OVERNIGHT HOURS
AS A LOW LEVEL JET STRENGTHENS. THE BEST CHANCES FOR THUNDER
REMAIN FROM SOUTH CENTRAL SOUTH DAKOTA THROUGH NORTHEAST SOUTH
DAKOTA...MAINLY FORECAST TO POSSIBLY IMPACT THE KATY TAF SITE.
BEYOND BRIEF PERIODS OF REDUCED CIGS/VSBYS ASSOCIATED WITH
STRONGER STORMS...MVFR/IRF CIGS AND VSBYS ARE ALSO POSSIBLE AT THE
KATY TAF SITE. THE WARM MOIST AIRMASS IN PLACE WILL LIKELY RESULT IN
LOWER CLOUDS AND THE POTENTIAL FOR PATCHY FOG DEVELOPMENT THROUGH
THE EARLY MORNING HOURS. FRIDAY...A WEAK COLD FRONT WILL SLIDE
FROM NORTHWEST TO SOUTHEAST ACROSS THE STATE OF SOUTH DAKOTA.
WINDS WILL SWITCH AROUND TO THE EAST NORTHEAST BEHIND THE FRONT.
ADDITIONAL SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE
BOUNDARY AND IN CONJUNCTION WITH UPPER LEVEL ENERGY FRIDAY NIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...WISE
SHORT TERM...MOHR
LONG TERM...DORN
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
305 AM EDT FRI JUL 11 2014
.SHORT TERM (TODAY AND TONIGHT)...
SURFACE HIGH PRESSURE TO THE NORTH WILL PROVIDE A LOW LEVEL NE
FLOW...WITH A DRY NW FLOW THROUGH THE MID AND UPPER LEVELS. FORECAST
SOUNDINGS IN THE TN VALLEY LOOK PRETTY STABLE TODAY...SO MOST OF THE
AREA SHOULD STAY DRY. SOME CONVECTIVE DEVELOPMENT MAY OCCUR THIS
AFTERNOON IN THE HIGHER TERRAIN OF SW NC AND THE SMOKIES...AS
DEPICTED BY THE RAP AND HRRR. WILL INCLUDE A SLIGHT CHANCE POP IN
THOSE AREAS. ANYTHING THAT DEVELOPS SHOULD DISSIPATE BY 00Z. WILL
HAVE TEMPERATURES TODAY A LITTLE HIGHER THAN YESTERDAY...BUT BELOW
GFS MOS GUIDANCE WHICH SEEMS TOO WARM.
.LONG TERM (SATURDAY THROUGH THURSDAY)...
A FLAT RIDGE OF HIGH PRESSURE WILL BE OVER THE TENNESSEE VALLEY
FOR SATURDAY AND SUNDAY WITH A GRADUAL INCREASE IN
MOISTURE/INSTABILITY. ONLY FORCING FOR CONVECTION WITH BE
OROGRAPHIC..SO WILL HAVE POPS MAINLY OVER THE HIGHER ELEVATIONS.
FOR MONDAY AND TUESDAY...AN UNUSUALLY STRONG UPPER LOW WILL DROP
ACROSS THE GREAT LAKES REGION. STRONG UPPER TROUGHING WILL BE OVER
THE TENNESSEE VALLEY/SOUTHERN APPALACHIANS WITH A COLD FRONT PASSAGE
FOR LATE MONDAY NIGHT/TUESDAY. INCREASING INSTABILITY AHEAD OF THE
BOUNDARY WILL INCREASE THE COVERAGE OF STORMS FOR MONDAY/MONDAY
NIGHT AND TUESDAY. DUE TO THE STRENGTH OF THE FRONT FOR JULY AND
DECENT INSTABILITY...I AM CONCERNED FOR STRONG TO SEVERE STORMS FOR
MONDAY AFTERNOON/EVENING. MAIN CONCERN WILL BE DAMAGING WINDS.
WILL CALL FOR HIGH CHANCE/LIKELY POPS FOR MONDAY AFTERNOON THROUGH
TUESDAY. AS TIMING OF FROPA AND POTENTIAL OF PRE-FRONTAL TROUGH
BECOMES MORE CLEAR...CATEGORICAL POPS WILL LIKELY BE NEEDED.
AN UNSEASONABLY COOL AIRMASS SPILLS INTO THE AREA FOR WEDNESDAY AND
THURSDAY WITH MAINLY DRY CONDITIONS. GENERALLY WENT A DEGREE OR TWO
COOLER THAN GFS MEX HIGHS THROUGH THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 90 69 93 70 / 10 10 10 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 88 67 91 69 / 10 10 10 10
OAK RIDGE, TN 88 66 91 68 / 10 10 10 10
TRI CITIES AIRPORT, TN 88 63 88 64 / 10 10 10 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS/DH
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
355 AM CDT Fri Jul 11 2014
.SHORT TERM...
(Today and tonight)
Rain chances return to much of West Central TX today as an
upper-level cyclone that has cut off from the TUTT (tropical upper
tropospheric trough) moves west across the Mexican state of
Coahuila. A slug of deep moisture attendant to this feature is
moving northwest up the Rio Grande Valley and will increase
precipitable water values to as much as 1.70" across the southwest
half of the CWA this morning, with column moisture values dropping a
bit during the afternoon hours through vertical mixing. The HRRR and
WRF-ARW develop isolated convection through mid afternoon across
much of the area, but the best chance of precipitation will reside
southwest of a Sterling City to Junction line. Mid-level cloud cover
will keep temps in the upper 80s to lower 90s across the
southwestern zones today, with mid 90s expected once again across
the Big Country and Heartland.
I do not anticipate a nocturnal flare-up tonight over West Central
TX (like we are currently seeing to our south) given the anticipated
location of the TUTT low. However, a few showers or thunderstorms
may linger into the evening hours, dissipating shortly after sunset.
Overnight lows will again be seasonal, bottoming out in the upper
60s to mid 70s.
So what is this TUTT low? A TUTT low is a cold core cyclone,
typically located near the tropopause (near 200 mb). These features
are not uncommon during the summer and often produce precipitation
during the summer months as they drift to the west along the
southern flank of the subtropical ridge. Per Whitfield and Lyons
(1992), precipitation is favored on the eastern flank of the TUTT
low, albeit skewed to the southeast quadrant.
.LONG TERM...
(Saturday through Thursday)
TUTT will be moving west of West Central Texas Saturday, but
cloudiness in southwest zones, including Crockett county, will keep
temperatures in the lower 90s. Farther north in the Big Country,
highs in the upper 90s are expected.
Upper level high pressure will keep the region dry and warm into
Monday. However a weather pattern change is in store Tuesday on, as
a large upper low develops in the Great Lakes. This will bring West
Central Texas into northwest flow aloft. A cold front also moves in
Tuesday, becoming stationary over the region. This combination will
bring a chance of showers and thunderstorms through Thursday.
Locally heavy rainfall potential exists as precipitable waters
increase 1/2 inch...to 1.5 to 2 inches. Timing of storm complexes is
difficult this far out, so kept rain chances in the 20 to 30 percent
range. Both the EC and GFS models, however, are similar in timing of
the front and the upper pattern change, so there is increasing
confidence in shower and thunderstorm development.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 94 74 96 72 97 / 10 5 5 0 0
San Angelo 92 70 94 71 96 / 20 10 5 0 0
Junction 91 70 94 71 96 / 20 10 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Johnson/04
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
327 AM CDT FRI JUL 11 2014
.TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
SHORT TERM MODELS SHOWING A GENERAL WARM AIR ADVECTION PATTERN
ACROSS THE AREA DURING THIS TIME. 500 MB VORTICITY MAXIMUM OVER
SOUTHERN MINNESOTA HELPING GENERATE SCATTERED LIGHT SHOWERS OR
DRIZZLE ACROSS SOUTHEAST MINNESOTA INTO FAR NORTHERN IOWA. ACTIVITY
FURTHER TO THE WEST DRIVEN MAINLY BY 850 MB LOW LEVEL JET NOSE/WARM
AIR ADVECTION. THIS ACTIVITY WILL TRY TO SHIFT TOWARD THE AREA THIS
MORNING...BUT HRRR SHOWS IT HAVING A HARD TIME GETTING HERE WITH DRY
AIR IN LOW LEVELS.
MAY SEE SOME OF THIS ACTIVITY IN THE AFTERNOON ACROSS SOUTH CENTRAL
WISCONSIN...AS 700 MB MOISTURE INCREASES WITH WEAK ELEVATED CAPE.
KEPT EASTERN AREAS DRY. SHOULD SEE INCREASE IN CLOUDS TODAY...WHICH
MAY HOLD DOWN TEMPERATURES A BIT. 925 MB TEMPERATURE FIELDS SUGGEST
UPPER 70S INLAND...WITH MID 70S TURNING COOLER NEAR THE LAKE WITH
SOUTHEAST WINDS IN THE AFTERNOON.
850 MB LOW LEVEL JET NOSE AND FOCUSED WARM AIR ADVECTION REMAINS
SOUTHWEST AND SOUTH OF THE AREA TONIGHT. AREA FORECAST SOUNDINGS
SHOW ELEVATED CAPES INCREASING GRADUALLY...GETTING UP TO AROUND 700
J/KG IN THE FAR WEST. GENERAL WARM AIR ADVECTION SHOULD CONTINUE TO
BRING IN MOISTURE AT THE 700 MB LEVEL. CONTINUED TO GRADUALLY
INCREASE POPS TONIGHT...HIGHEST IN THE FAR SOUTH AND FAR SOUTHWEST
LATER TONIGHT. LOWS SHOULD REMAIN IN THE MID 60S.
.SATURDAY - CONFIDENCE...MEDIUM
MID LEVEL SHORTWAVE WILL APPROACH. 850 JET INCREASES TOWARDS SRN
WI DURG THE AFTN...ESP ON THE NAM. HOWEVER GFS AND ECMWF ARE
SHOWING A MORE GLANCING SHOT OF THE JETLET WITH THE NAM SHOWING A
MORE DEVELOPED 850 LOW ACROSS NRN WI WITH THE JET AXIS ACROSS
SRN/CNTRL WI. WARM FRONT WILL BE IN THE VCNTY OF SRN WI PER THE
GFS/ECMWF WITH SURFACE COLD FRONT ARRIVING SATURDAY NIGHT. WITH
THE MORE FAVORABLE NORTHWARD TRACK AND DEVELOPMENT SHOWN BY THE
NAM COMES WITH IT THE HIGHER CWASP NUMBERS...WHILE THE GFS AND
ECMWF SHOW LESS IMPRESSIVE NUMBERS. EVEN IN THE LATTER SCENARIO
THERE WILL BE ENOUGH FAVORABLE FACTORS IN PLACE FOR SOME DECENT
STORMS WITH 0-1KM SHEAR INCREASING TO 20 KNOTS AND 0-6KM SHEAR
35-45 KTS. FRONTOGENETICAL FORCING WILL INCREASE WITH TIME. WHILE
SOME DISAGREEMENT BETWEEN THE MODELS ON STORM SEVERITY THE
CONSISTENT MESSAGE IS SOME HEAVY RAINFALL POTENTIAL. PRECIPITABLE
WATER VALUES ON BOTH EXCEED 2 INCHES WITH A WEAKNESS IN CORFIDI
VECTORS LATER SAT AFTN INTO THE EVE HRS. SOME SVR POTENTIAL ON THE
TABLE PER SWODY1 ESP WITH NAM SOLUTION AND HIGHER CWASP BUT HEAVY
RAIN THREAT HAS SOME CONSENSUS AMONGST THE MODELS. SO AT THIS TIME
WILL OPT TO LEAVE SVR OUT OF THE GRIDS BUT MENTION SLGT RISK SVR
AND HEAVY RAIN POTENTIAL IN THE HWO.
.SUNDAY - CONFIDENCE...MEDIUM
WITH THE FRONT TO THE SOUTHEAST NW WINDS WILL USHER IN COOLER 850
TEMPS. THE NAM AND ECMWF ARE SHOWING A DRY SOLUTION WHILE THE GFS
HAS SHRA/ISOLD TSRA WITH A SECONDARY BOUNDARY. UPPER FLOW IS
BROADLY CYCLONIC WITH ANY VORT...MAINLY THE SHEAR/ELONGATED
VARIETY...ACROSS NORTHERN WI. WILL KEEP CHCY POPS FOR NOW BASED ON
COLLAB WITH SURROUNDING OFFICES.
.MONDAY - CONFIDENCE...MEDIUM
MORE PRONOUNCED INTRUSION OF VORTICITY AS LARGE UPPER LOW DRIVES
SOUTHEAST FROM CANADA INTO WISCONSIN. EXPECT BETTER COVERAGE OF
SHRA IN THIS REGIME. ALSO 850 TEMPS CONTINUE TO TAKE A TUMBLE TO
UNDER 10C.
.TUESDAY - CONFIDENCE...MEDIUM
UPPER LOW SHIFTS A BIT EAST INTO
LOWER MI. FLOW ACROSS SRN WI STILL STRONGLY CYCLONIC SO WITH THE GFS
AND ECMWF STILL SHOWING QPF IN THIS REGIME WILL KEEP SHRA POTENTIAL
IN THE FCST. A VERY COOL AIRMASS WILL BE IN PLACE FOR JULY
STANDARDS. 925 TEMPS ONLY MODIFY TO 10-13C IN THE AFTN HRS...WHICH
TRANSLATES TO HIGHS FOR MOST NOT GETTING OUT OF THE MID 60S.
.WEDNESDAY - CONFIDENCE...MEDIUM
UPPER FLOW STILL SHOWING A CYCLONIC CURVATURE THOUGH SURFACE HIGH
DRAWS CLOSER AND AIRMASS DRIES OUT. MAY NEED A SMALL CHANCE AS WE
GET CLOSER BUT FOR NOW WILL GO WITH THE DRY ALLBLEND AND COLLAB
WITH SURROUNDING OFFICES.
.THURSDAY - CONFIDENCE...MEDIUM
LINGERING CYCLONIC FLOW CONTINUES TO LOSE ITS GRIP WITH A DRY AND
WEAKER NORTHWEST FLOW EXPECTED. 925 TEMPS MODIFY A BIT DEEPER INTO
THE TEENS CELSIUS.
&&
.AVIATION/12Z TAFS/...VFR CONDITIONS ARE EXPECTED TODAY INTO MOST OF
TONIGHT. MIDDLE TO HIGH CLOUDS WILL CONTINUE TO INCREASE ACROSS THE
AREA TODAY...AS WARMER AIR MOVES INTO THE REGION. ANY RAIN SHOWER
ACTIVITY SHOULD WEAKEN AS IT MOVES EAST TOWARD MADISON THIS MORNING...
BUT MAY SEE WIDELY SCATTERED ACTIVITY THIS AFTERNOON THERE. NO MENTION
IN TAFS FOR NOW DUE TO LOW AREAL COVERAGE. SOUTH WINDS WILL BECOME
GUSTY AT TIMES AT MADISON TODAY...WITH WINDS SHIFTING SOUTHEAST AT
THE EASTERN SITES THIS AFTERNOON WITH LAKE BREEZE.
LEFT VICINITY SHOWER/THUNDERSTORM WORDING IN TAFS FOR LATER
TONIGHT...AS MORE WARM AND MOIST AIR TRIES TO PUSH INTO THE AREA.
BEST CHANCES WILL REMAIN JUST SOUTH OF THE AREA. MAY SEE LIGHT FOG
DEVELOP WITH MVFR VISIBILITIES LATER TONIGHT ACROSS TAF SITES...AS
WINDS WEAKEN SOMEWHAT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...WOOD
SATURDAY THROUGH THURSDAY...COLLAR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
255 AM CDT FRI JUL 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN SHORT TERM CONCERN IS ON PRECIPITATION CHANCES TODAY.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE CENTRAL U.S....A WEAK RIDGE OVER MICHIGAN...
A SHORTWAVE TROUGH CROSSING MN WITH THE CORE NEAR DULUTH...A WEAK
SHORTWAVE CROSSING NEBRASKA...AND A DEEP UPPER TROUGH OVER SOUTH
CENTRAL CANADA. DPVA AHEAD OF THE MN SHORTWAVE TROUGH COMBINED WITH
850MB MOISTURE TRANSPORT SEEN BY STRONGER 850MB WINDS ON RADARS FROM
EASTERN SOUTH DAKOTA INTO NORTHERN MN HAS SUPPORTED SHOWERS AND
STORMS NORTH OF MINNEAPOLIS. THE NEBRASKA SHORTWAVE AND ANOTHER NOSE
OF 850MB MOISTURE TRANSPORT HAS SUPPORTED OTHER SHORTWAVES AND
STORMS FROM NEBRASKA INTO SIOUX FALLS AREA. THE FORECAST AREA
MEANWHILE HAS ONLY SEEN A FEW LIGHT SHOWERS WEST OF THE MS RIVER
STEMMING FROM ACCAS CLOUDS ON THE EASTERN EXTENT OF THE MOISTURE
TRANSPORT ZONE. THE AIRMASS OVER THE REGION HAS CERTAINLY BECOME
WARMER AND MORE MOIST OVER THE PAST 24 HOURS. 850MB TEMPS HAVE
CLIMBED TO 12-15C ACCORDING TO 00Z SOUNDINGS WITH 20-25C READINGS IN
THE DAKOTAS. MEANWHILE...PRECIPITABLE WATER VALUES ARE UP TO 1-1.5
INCHES WITH A 2 INCH MAXIMA NEAR SIOUX FALLS PER RAP AND GOES
DERIVED.
THE FORECAST FOR TODAY IS RADICALLY DRIER THAN WHAT IT LOOKED LIKE
24 HOURS AGO. MUCH OF THIS IS A FUNCTION OF THE 850MB MOISTURE
TRANSPORT BEING INCORRECT. INSTEAD OF THE NOSE COMING RIGHT AT THE
FORECAST AREA...ITS IN NORTHERN MN AND NEAR SIOUX FALLS.
ADDITIONALLY...THE SHORTWAVE TRACKING ACROSS MN IS MOVING FASTER
THAN EARLIER PROJECTIONS.
RE-ANALYZING TODAYS FORECAST. IT APPEARS THE SHOWERS AND STORMS
TAKING PLACE NORTH OF MINNEAPOLIS WILL PROGRESS TO THE EAST THIS
MORNING WITH THE CORE OF THE SHORTWAVE TROUGH...PERHAPS CLIPPING
TAYLOR COUNTY. TO THE WEST...REGARDING THE SHOWERS AND STORMS
CROSSING NEBRASKA AND SIOUX FALLS...THESE MAY MAKE IT INTO NORTHEAST
IOWA LATE IN THE MORNING PER HRRR AND 11.00Z GFS PROGS. HOWEVER...
THE 850MB MOISTURE TRANSPORT NOSE SUPPORTING THEM IS PROGGED TO
DRAMATICALLY WEAKEN IN ALL MODELS...SO ITS POSSIBLE THEY DIE BEFORE
REACHING NORTHEAST IOWA. THIS LEAVES REALLY THE ONLY OTHER THREAT OF
PRECIPITATION FOR THE MORNING BEING THIS ACCAS WHICH COULD SHOWER
HERE AND THERE ACROSS MUCH OF THE FORECAST AREA DURING THE MORNING.
HEADING INTO THE AFTERNOON...DESPITE THE FACT THAT THE HIGHER
PRECIPITABLE WATER ZONE OVER SIOUX FALLS AREA IS PROGGED TO SHIFT
EAST INTO THE AREA...THERES NO FORCING TO DO ANYTHING WITH THAT
MOISTURE. SURFACE BOUNDARY WISE...A COLD FRONT LOOKS TO EXTEND
SOUTHWEST TO NORTHEAST ACROSS MN WHILE A WARM FRONT IS ACROSS
NEBRASKA...BOTH BEING WEST OF THE AREA. ADDITIONALLY...500MB HEIGHTS
ARE RISING IN THE WAKE OF THE SHORTWAVE TROUGH TO PROVIDE
SUBSIDENCE. 11.00Z NAM/GFS/REGIONAL CANADIAN ARE ALL DRY AND HAVE
TRENDED THE FORECAST EVEN MORE IN THAT DIRECTION. ONLY THE 11.00Z
HIRES ARW HAS SOME ISOLATED DIURNAL CONVECTION SO KEPT A 20 PERCENT
CHANCE IN CASE. WITH A DRIER FORECAST AND 850MB TEMPS BETWEEN 14-16C
TODAY...HAVE RAISED TEMPERATURES A FEW DEGREES. PLENTY OF MID CLOUD
WILL HAMPER HIGHS FROM REACHING FULL POTENTIAL...THOUGH.
FOR TONIGHT...THERE IS GOOD MODEL AGREEMENT FOR 850MB MOISTURE
TRANSPORT TO INCREASE ACROSS THE CENTRAL PLAINS INTO THE I-80
CORRIDOR ACROSS NEBRASKA AND IOWA. THE CAUSE FOR THE INCREASE IS
TIED TO A FAIRLY STRONG MONSOONAL SHORTWAVE SEEN ON WATER VAPOR
IMAGERY OVER LAS VEGAS...ROTATING UP AROUND THE CENTRAL PLAINS RIDGE
INTO SOUTH DAKOTA BY 12Z SATURDAY. GIVEN THE HIGH PRECIPITABLE WATER
AIRMASS IN PLACE...IT SEEMS ALL BUT CERTAIN SHOWERS AND
THUNDERSTORMS WILL FIRE ON THE NOSE OF THAT 850MB MOISTURE TRANSPORT
ZONE. SOME OF THESE STORMS COULD WORK INTO LOCATIONS SOUTH OF
INTERSTATE 90 AFTER MIDNIGHT...THOUGH BELIEVE THE GREATER FOCUS FOR
THEM WILL OCCUR SOUTH AND WEST OF THE AREA PRIOR TO 12Z SATURDAY.
ALSO CANNOT RULE OUT A FEW SHOWERS AND STORMS THROUGH THE NIGHT
CROSSING TAYLOR/CLARK COUNTIES FROM THE COLD FRONT OVER MN TRACKING
THROUGH THERE. WITH A HIGH PRECIPITABLE WATER AIRMASS IN PLACE AND
MID CLOUD SPREADING IN FROM THE SOUTHWEST...ANTICIPATING A WARM
NIGHT. IN FACT...HIGHER DEWPOINTS ADVECTING IN COULD RESULT IN SOME
FOG.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN LONG TERM CONCERNS ARE ON SEVERE WEATHER POTENTIAL SATURDAY
AFTERNOON/EVENING AND THE UNSEASONABLY COLD AIR MONDAY INTO TUESDAY.
SATURDAYS FOCUS IS ENTIRELY ON THE CURRENT MONSOONAL SHORTWAVE NEAR
LAS VEGAS. MODEL CONSENSUS BRINGS THIS SHORTWAVE THROUGH OUR AREA AT
ABOUT THE TIME OF PEAK HEATING. 0-6KM...0-3KM AND 0-1KM SHEAR VALUES
ALL REALLY INCREASE THROUGH THE DAY IN RESPONSE TO THE SHORTWAVE...
TOPPING OUT AT 21Z AROUND 60 KTS...45 KT AND 20-25 KT RESPECTIVELY.
THIS IS PLENTY FOR ORGANIZED SEVERE CONVECTION. THE DEEPER SHEAR IS
ALSO NICELY CYCLONICALLY CURVED. MEANWHILE...THE ATMOSPHERE IS
JUICED UP PRECIPITABLE WATER WISE WITH VALUES OF 2 INCHES GETTING
ADVECTED INTO THE AREA. ALSO GOOD MODEL CONSENSUS EXISTS FOR 750-
2000 J/KG OF MLCAPE TO BUILD UP SOUTH OF I-90...LIMITED BY PLENTIFUL
CLOUD COVER...WITH EVEN HIGHER VALUES BUILDING UP IN A CAPPED
AIRMASS NEAR I-80. THUS...SEE SOME CHANCE FOR A SEVERE WEATHER EVENT
SATURDAY AFTERNOON. HAIL THREAT IS LIMITED BY THE HIGH PRECIPITABLE
WATER AND WARM CLOUD DEPTHS AROUND 4 KM. THESE PARAMETERS INCREASE
THE HEAVY RAIN AND FLASH FLOODING CONCERN...HOWEVER...THE STRONG
SHEAR SHOULD PROMOTE PROGRESSIVE CONVECTION. ADDITIONALLY...THE
RECENT DRY PERIOD WILL ALLOW SOILS TO ABSORB MORE WATER. THE STRONG
SHEAR DEFINITELY MAKES DAMAGING WINDS A CONCERN. CANNOT RULE OUT A
TORNADO EITHER GIVEN THE 0-1KM SHEAR AND A WARM FRONT LIKELY TO SIT
NEAR/SOUTH OF US-20. REALLY THE ONLY ISSUE WITH SATURDAY AMONGST THE
MODELS IS THE PLACEMENT OF AFTERNOON CONVECTION. THE 11.00Z
NAM/REGIONAL CANADIAN ARE ALONG/NORTH OF I-90...WHICH BOTH HAVE HAD
A NORTHWARD BIAS TO SEVERE CONVECTIVE EVENTS THIS YEAR. PREFER THE
FARTHER SOUTH 11.00Z GFS/ECMWF/HIRES ARW. MUCH OF THE CONVECTION
SHOULD PUSH SOUTHEAST OF THE AREA BY 03Z WITH THE PASSAGE OF THE
SHORTWAVE...FOLLOWED BY SIGNIFICANT DRYING OF PRECIPITABLE WATER OF
NEARLY 1 INCH BY 12Z SUNDAY.
ON SUNDAY...THE DEEP UPPER TROUGH OVER SOUTH CENTRAL CANADA IS
PROGGED TO BEGIN ITS DESCENT INTO OUR REGION. A COLD FRONT AHEAD OF
THE TROUGH SHOULD DROP SOUTH THROUGH THE AREA...AGAIN AT THE TIME OF
PEAK HEATING. 0-6KM SHEAR IS RUNNING 40-50 KT WITH 0-3KM AT 25-35KT.
HOWEVER...INSTABILITY LOOKS TO BE SEVERELY LACKING RESULTING FROM THE
SIGNIFICANT DRYING OF PRECIPITABLE WATER SATURDAY NIGHT. 11.00Z GFS
HAS THE GREATEST INSTABILITY AT 500-1000 J/KG OF MLCAPE...BUT THINK
ITS DEWPOINTS IN THE LOW 60S POOLING AROUND THE BOUNDARY ARE TOO
HIGH. FOR NOW HAVE CONTINUED SOME CHANCES OF PRECIPITATION FOR THE
FRONT...BUT BELIEVE THE DRIER 11.00Z ECMWF/CANADIAN/NAM WILL COME
TRUE. MUCH COOLER AND DRIER AIR SINKS SOUTH INTO THE AREA SUNDAY
NIGHT IN THE WAKE OF THE FRONT.
MONDAY AND TUESDAY STILL LOOK LIKE A TASTE OF FALL AS A SHOT OF
MODIFIED ARCTIC AIR COMES INTO THE REGION. AN UPPER LOW WITHIN THE
DEEP UPPER TROUGH IS PROGGED TO SLIDE ACROSS NORTHERN WI MONDAY
EVENING. COOL TEMPERATURES ALOFT...DAYTIME HEATING AND DPVA AHEAD OF
THE UPPER LOW SHOULD PROMOTE SHOWER DEVELOPMENT ACROSS MUCH OF THE
REGION MONDAY. THIS WILL BE ESPECIALLY TRUE OVER NORTHERN WI. HAVE
RAISED PRECIPITATION CHANCES AND FURTHER INCREASES MAY BE NECESSARY.
PRECIPITATION CHANCES CONTINUE INTO TUESDAY AS WELL WITH THE COLD
AIR ALOFT STILL AROUND. 850MB TEMPERATURES PLUMMET TO 4-6C ON MONDAY
ON A BREEZY NORTHWEST WIND AND HOLD THERE THROUGH TUESDAY. THESE ARE
2-2.5 STANDARD DEVIATIONS BELOW NORMAL SUGGESTING RECORDS ARE
POSSIBLE. SEE CLIMATE SECTION BELOW FOR MORE DETAILS.
THE WEATHER QUIETS DOWN THEN FOR WEDNESDAY AND THROUGH THE END OF
THE WEEK AS THE DEEP UPPER TROUGH GRADUALLY EJECTS OUT. PLENTIFUL
DRY CANADIAN AIR PLUNGES SOUTH THROUGH MUCH OF THE EASTERN U.S....
RESULTING IN A DRY FORECAST FOR WEDNESDAY AND BEYOND. TEMPERATURES
WILL GRADUALLY WARM EACH DAY AS THE SUN HELPS MODIFY THE COLD AIR.
WE SHOULD BE BACK CLOSE TO NORMAL BY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1120 PM CDT THU JUL 10 2014
REGIONAL RADARS CONTINUE TO SHOW SOME LIGHT SHOWERS MOVING TOWARD
THE AREA BUT SURFACE OBSERVATIONS SHOW LITTLE IF ANYTHING IS
HITTING THE GROUND AND WHAT IS...IS NOTHING MORE THAN SHOWERS.
THESE SHOWERS ARE IN ASSOCIATION WITH A SHORT WAVE TROUGH MOVING
ACROSS NORTHERN MINNESOTA. THE 11.02Z HRRR SHOWS THE MAIN AREA OF
SHOWERS PASSING NORTH OF THE REGION WITH THE SHORT WAVE TROUGH
WITH JUST THE SPRINKLES COMING THROUGH OVERNIGHT AND WILL CONTINUE
TO SHOW A VCSH FOR THIS ACTIVITY WITH VFR CEILINGS. MORE
CONVECTION HAS FORMED OVER NEBRASKA AHEAD OF THE NEXT SHORT WAVE
TROUGH. THIS WAVE IS SHOWN BY THE 11.00Z NAM TO SLIDE SOUTH OF THE
AREA ACROSS IOWA BUT THE ACTIVITY MAY DISSIPATE AS IT APPROACHES.
BOTH THE HRRR AND NAM SHOW THIS HAPPENING AS THE ACTIVITY MOVES
OUT OF THE CAPE AXIS. WITH THIS ACTIVITY EXPECTED TO MISS THE
AREA...WILL DROP THE VCSH BY MID MORNING WHEN THE GRADIENT BECOMES
TIGHT ENOUGH AND THE MIXING GETS GOING TO PRODUCE SOME GUSTY SOUTH
WINDS. LOOK FOR THESE GUSTS TO DIMINISH EARLY FRIDAY EVENING AS
THE LOW LEVEL INVERSION DEVELOPS AND CUTS OFF THE MIXING.
&&
.CLIMATE...
ISSUED AT 255 AM CDT FRI JUL 11 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI
RIVER VALLEY. FORECAST HIGH TEMPERATURES FOR TUESDAY ARE 65 AT
ROCHESTER AND 66 AT LA CROSSE. THESE TEMPERATURES WOULD BREAK THE
RECORD LOWEST HIGH TEMPERATURES FOR JULY 15TH. THE OLD RECORDS ARE
68 AT LA CROSSE SET BACK IN 1962 AND 67 AT ROCHESTER ALSO SET
BACK IN 1962.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
CLIMATE...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1120 PM CDT THU JUL 10 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 337 PM CDT THU JUL 10 2014
A SHORTWAVE TROUGH WILL MOVE ACROSS SOUTHERN MINNESOTA/NORTHERN
IOWA THIS EVENING AND EDGE INTO WESTERN SECTIONS OF THE FORECAST
AREA AROUND 00Z. THIS WAVE WILL BRING ISOLATED SHOWERS AND MAYBE A
COUPLE OF THUNDERSTORMS TO THESE AREAS AS IT MOVES IN. THIS
ACTIVITY SHOULD APPROACH THE MISSISSIPPI RIVER LATE THIS EVENING
INTO THE OVERNIGHT HOURS AND WILL INCREASE IN COVERAGE AS 850 MB
MOISTURE TRANSPORT EDGES INTO THE FORECAST AREA. INSTABILITY IS
LIMITED SO HAVE HELD THUNDERSTORM COVERAGE TO ISOLATED UNTIL
FRIDAY MORNING. FORECAST MODELS JUST AREN/T DOING THAT GREAT OF A
JOB HANDLING THIS SHORTWAVE. MESOSCALE MODELS SEEM TO HAVE A
BETTER HANDLE ON THIS WAVE SO HAVE LEANED TOWARDS THEM FOR
PRECIPITATION CHANCES LATE TONIGHT INTO FRIDAY. STRONGER 850 MB
MOISTURE TRANSPORT MOVES INTO THE AREA LATE TOMORROW MORNING INTO
THE AFTERNOON HOURS SO THIS IS WHEN WE SHOULD SEE SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS MUCH OF THE FORECAST AREA. A WEAK
FRONTAL BOUNDARY THEN SAGS SOUTH INTO THE REGION LATE FRIDAY
AFTERNOON INTO FRIDAY NIGHT.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 337 PM CDT THU JUL 10 2014
THE BOUNDARY SETTLES IN FRIDAY NIGHT INTO EARLY SATURDAY MORNING
WITH A VERY BAGGY PRESSURE GRADIENT OVER THE FORECAST AREA. THIS
WEAK GRADIENT COMBINED WITH THE EXPECTED RAIN ON FRIDAY ALONG WITH
DEWPOINTS CLIMBING INTO THE MID TO UPPER 60S WILL SET THE STAGE
FOR FOG DEVELOPMENT. THERE IS SIGNALS IN THE SREF/ARW/NMM FOR
DENSE FOG OVER PORTIONS OF THE FORECAST AREA. IF THESE TRENDS
CONTINUE...FOG COVERAGE WILL NEED TO BE INCREASED AND THERE WOULD
BE THE POTENTIAL TO SEE DENSE FOG. WILL HAVE TO KEEP A VERY CLOSE
EYE ON THIS. THE BOUNDARY THEN EDGES SOUTH SATURDAY AFTERNOON INTO
NORTHEAST IOWA/FAR SOUTHWEST WISCONSIN. AFTERNOON 0-3 KM MUCAPE
VALUES CLIMB INTO THE 1500-1700 J/KG RANGE. 0-6 KM BULK SHEAR
ISN/T ALL THAT GREAT SATURDAY AFTERNOON...RANGING FROM 25 TO 35
KTS. HOWEVER...THERE COULD BE SLIGHTLY STRONGER SHEAR SOUTH OF
INTERSTATE 90 WHERE A SHORTWAVE COULD BE A LITTLER STRONGER THAN
WHAT FORECAST MODELS ARE SUGGESTING. THE MAIN WARM FRONT LOOKS TO
BE POSITIONED OVER CENTRAL IOWA INTO NORTHERN ILLINOIS. THIS AREA
COULD SEE BETTER SHEAR FOR SUPERCELLS AND POSSIBLY SOME TORNADOES
NEAR THE FRONT. ACROSS THE LOCAL AREA...PULSE SEVERE STORMS LOOK
TO BE THE MAIN HAZARD WITH LARGE HAIL AND POSSIBLY DAMAGING WINDS.
LOCALLY HEAVY RAINFALL MAY ALSO BE A CONCERN.
AN UNSEASONABLY DEEP TROUGH DIVES INTO THE REGION LATE SUNDAY
INTO MONDAY NIGHT. THERE IS THE POTENTIAL TO SEE SOME STRONGER TO
POSSIBLY SEVERE STORMS SUNDAY AFTERNOON WITH STRONGER SHEAR OVER
THE REGION. HOWEVER...INSTABILITY WILL BE A MAJOR LIMITING FACTOR.
THE COLDEST AIR WILL SETTLE IN FOR TUESDAY WHEN 850 MB
STANDARDIZED ANOMALIES FALL INTO THE -1.5 TO -2.0 RANGE. TUESDAY
WILL LIKELY BE A DAY FOR RECORD COLD HIGH TEMPERATURES. SEE
CLIMATE SECTION BELOW. TEMPERATURES LOOK TO MODERATE A BIT IN THE
WAKE OF THIS TROUGH WEDNESDAY INTO THURSDAY...WITH HIGHS CLIMBING
BACK INTO THE 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1120 PM CDT THU JUL 10 2014
REGIONAL RADARS CONTINUE TO SHOW SOME LIGHT SHOWERS MOVING TOWARD
THE AREA BUT SURFACE OBSERVATIONS SHOW LITTLE IF ANYTHING IS
HITTING THE GROUND AND WHAT IS...IS NOTHING MORE THAN SHOWERS.
THESE SHOWERS ARE IN ASSOCIATION WITH A SHORT WAVE TROUGH MOVING
ACROSS NORTHERN MINNESOTA. THE 11.02Z HRRR SHOWS THE MAIN AREA OF
SHOWERS PASSING NORTH OF THE REGION WITH THE SHORT WAVE TROUGH
WITH JUST THE SPRINKLES COMING THROUGH OVERNIGHT AND WILL CONTINUE
TO SHOW A VCSH FOR THIS ACTIVITY WITH VFR CEILINGS. MORE
CONVECTION HAS FORMED OVER NEBRASKA AHEAD OF THE NEXT SHORT WAVE
TROUGH. THIS WAVE IS SHOWN BY THE 11.00Z NAM TO SLIDE SOUTH OF THE
AREA ACROSS IOWA BUT THE ACTIVITY MAY DISSIPATE AS IT APPROACHES.
BOTH THE HRRR AND NAM SHOW THIS HAPPENING AS THE ACTIVITY MOVES
OUT OF THE CAPE AXIS. WITH THIS ACTIVITY EXPECTED TO MISS THE
AREA...WILL DROP THE VCSH BY MID MORNING WHEN THE GRADIENT BECOMES
TIGHT ENOUGH AND THE MIXING GETS GOING TO PRODUCE SOME GUSTY SOUTH
WINDS. LOOK FOR THESE GUSTS TO DIMINISH EARLY FRIDAY EVENING AS
THE LOW LEVEL INVERSION DEVELOPS AND CUTS OFF THE MIXING.
&&
.CLIMATE...
ISSUED AT 337 PM CDT THU JUL 10 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI
RIVER VALLEY. FORECAST HIGH TEMPERATURES FOR TUESDAY ARE 65 AT
ROCHESTER AND 66 AT LA CROSSE. THESE TEMPERATURES WOULD BREAK THE
RECORD LOWEST HIGH TEMPERATURES FOR JULY 15TH. THE OLD RECORDS ARE
68 AT LA CROSSE SET BACK IN 1962 AND 67 AT ROCHESTER ALSO SET
BACK IN 1962.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...04
CLIMATE...WETENKAMP
AREA FORECAST DISCUSSION
NWS RENO NV
620 AM PDT FRI JUL 11 2014
.UPDATE...
UPDATING TO REMOVE THUNDERSTORMS FROM THIS MORNING. INSTABILITY
HAS BEEN WEAK OVERNIGHT WITH ONLY SHOWERS ACROSS NORTHEAST
CALIFORNIA AND NORTHWEST NEVADA. EXPECT THIS TREND TO CONTINUE
THROUGH THE MORNING WITH ONLY SHOWERS. OTHERWISE, NO CHANGES AS
SOLAR HEATING SHOULD RESULT IN ISOLATED SHOWERS AND STORMS THIS
AFTERNOON FOCUSED NORTH OF I-80. WALLMANN
&&
.FIRE WEATHER...
WITH INSTABILITY WEAKER THAN EXPECTED OVERNIGHT, ONLY LIGHT
SHOWERS FORMED. LIGHTNING WAS LIMITED TO A FEW ISOLATED STRIKES
WEST OF THE CREST. WITH THIS TREND TO CONTINUE THROUGH THE
MORNING, HAVE CANCELED THE RED FLAG WARNING. ISOLATED
THUNDERSTORMS ARE EXPECTED TO FORM LATER TODAY, BUT WITH THE
MOISTURE IN PLACE EXCEPT THEM TO BE MOSTLY WET. WALLMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 311 AM PDT FRI JUL 11 2014/
SYNOPSIS...
ISOLATED TO SCATTERED THUNDERSTORMS FOR THE SIERRA AND WESTERN
NEVADA MAY CONTINUE NORTH OF SUSANVILLE AND GERLACH THIS MORNING.
ANOTHER ROUND OF STORMS IS POSSIBLE FROM NEAR INTERSTATE 80 NORTH
THIS AFTERNOON BEFORE HIGH PRESSURE STRENGTHENS OVER THE WEEKEND
FOR DRIER AND HOTTER CONDITIONS.
SHORT TERM...
EXPANDED COVERAGE OF THUNDERSTORMS SLIGHTLY FURTHER SOUTH FOR THIS
AFTERNOON AND EVENING. NO OTHER MAJOR CHANGES TO THE SHORT TERM
FORECAST.
AS OF 3 AM, WEAK ISOLATED-SCATTERED SHOWERS WERE MOVING NORTHWEST
ACROSS NORTHEASTERN CALIFORNIA AND NORTHWEST NEVADA MAINLY NORTH OF
HIGHWAY 50. WATER VAPOR IMAGERY ALSO SHOWED THE NEGATIVELY-TILTED
TROUGH JUST OFF THE CALIFORNIA COAST AND ITS ASSOCIATED JET
PUSHING INTO NORTHERN CALIFORNIA THIS MORNING. ISOLATED
THUNDERSTORMS AND LIGHTNING HAVE ALREADY BEGUN TO AFFECT AREAS
WEST OF THE CREST NEAR GRASS VALLEY AND REDDING EARLY THIS
MORNING. THUNDERSTORMS ARE EXPECTED TO BECOME MORE WIDESPREAD AS
FORCING/INSTABILITY PUSHES IN WITH THE TROUGH THROUGH THE MORNING.
FORECAST MODELS AND HIGH RESOLUTION FORECASTS (HRRR) STILL
INDICATING THAT THE BEST FORCING WILL FOCUS WEST OF THE SIERRA AND
ACROSS FAR NORTHERN CALIFORNIA AND SOUTHERN OREGON. WITH THE
POTENTIAL FOR ELEVATED CONVECTION ACROSS NORTHEASTERN CALIFORNIA
AND NORTHWEST NEVADA, DRY LIGHTNING AND POSSIBLE FIRE STARTS IS A
CONCERN. CHECK OUT THE FIRE WEATHER DISCUSSION FOR MORE DETAILS.
THE MAIN UPPER FORCING/JET NOSE SLIDES INTO EXTREME NORTHERN
NEVADA AND SOUTHEAST OREGON BETWEEN MID MORNING AND EARLY
AFTERNOON TODAY. WITH THE SLOWER TIMING OF THE INCOMING TROUGH AND
ITS UPPER LEVEL FORCING, WENT AHEAD AND SPREAD THE POTENTIAL FOR
ISOLATED THUNDERSTORMS FURTHER SOUTH FOR THIS AFTERNOON/EVENING.
THUNDERSTORMS WILL LIKELY FORM ALONG THE SIERRA AND THEN BE PUSHED
EASTWARD BY THE ZEPHYR WINDS IN THE AFTERNOON. KEPT THUNDERSTORMS
OUT OF TAHOE AND THE SIERRA FOR THIS REASON. OTHERWISE, INCREASING
SOUTHWEST FLOW ALOFT THROUGH THE DAY WILL GRADUALLY STABILIZE AND
DRY OUT THE ATMOSPHERE BY THE EVENING.
DRIER AND MORE STABLE AIR REALLY INVADES THE EASTERN SIERRA AND
WESTERN NEVADA BY SATURDAY AS THE FOUR CORNERS RIDGE BEGINS TO BUILD
WESTWARD INTO CALIFORNIA AND NEVADA. DAYTIME HIGHS ON SATURDAY WILL
BE NEAR OR SLIGHTLY ABOVE AVERAGE, BUT EXPECT TO SEE A SIGNIFICANT
WARMUP INTO NEXT WEEK. ELW
LONG TERM...MONDAY THROUGH THURSDAY...
HIGH PRESSURE REMAINS OVER NEVADA NEXT WEEK WITH A DAILY THREAT OF
THUNDERSTORMS ALONG WITH ABOVE AVERAGE TEMPERATURES. THE MODELS,
ESPECIALLY THE GFS AND EC, REMAIN IN VERY GOOD AGREEMENT ON THIS.
GFS/EC NOW IN BETTER AGREEMENT WITH SOME MID-LEVEL COOLING WITH MORE
INSTABILITY MONDAY ALONG AND JUST EAST OF THE SIERRA CREST. WITH
MOISTURE STILL IN PLACE FROM THIS WEEK`S EVENT, THUNDERSTORMS ARE
POSSIBLE IN THIS AREA. TEMPERATURES WILL REMAIN HOT AND INTO THE
TRIPLE DIGITS IN WESTERN NEVADA AND 80S TO LOW 90S SIERRA. WITH THIS
BEING THE FIRST THUNDERSTORM DAY, A MIX OF WET AND DRY ARE POSSIBLE
WITH PW AROUND 0.8 INCHES. MONDAY WOULD BE THE BIGGEST CONCERN FOR
FIRE WEATHER.
ON TUESDAY INTO WEDNESDAY, THE HIGH SHIFTS A BIT FURTHER EAST INTO
EASTERN NEVADA WITH MOISTURE STREAMING UP FROM THE MONSOON. EXPECT
COVERAGE OF STORMS TO INCREASE WITH THE BEST DAY FOR STORMS LIKELY
WEDNESDAY. DAYTIME TEMPS WILL LIKELY SEE A COOLING TREND DUE TO
INCREASED CLOUD COVER.
ON THURSDAY, IT APPEARS A WEAK TROUGH WILL BEGIN TO MOVE INTO THE
PACNW CREATING A LIGHT SW FLOW. THIS SHOULD START A DRYING TREND SO
BEGAN TO TREND THE THREAT OF STORMS DOWNWARD. WALLMANN
AVIATION...
ISOLATED THUNDERSTORMS REMAIN POSSIBLE THIS MORNING, MAINLY NORTH OF
LAKE TAHOE INTO LASSEN COUNTY. BKN-OVC CIGS TO REMAIN NEAR 10 KFT.
THIS AFTERNOON, EXPECT MORE SHOWERS AND STORMS TO BE CONCENTRATED
NORTH OF I-80 WITH SFC WND GUSTS TO 40 KTS THE PRIMARY THREAT.
AFTERNOON SW WINDS ALSO LIKELY INTO THE RENO-TAHOE TERMINALS THIS
AFTERNOON WITH PEAK GUSTS 25 KTS 22-03Z. THIS WEEKEND LOOKS DRY WITH
THE NEXT THREAT OF THUNDERSTORMS NEXT WEEK. WALLMANN
FIRE WEATHER...
THIS MORNING, GOOD INSTABILITY ALOFT, STEEP UPPER LEVEL LAPSE RATES,
AND FORCING FROM THE MID AND UPPER-LEVEL WAVE WILL CONTINUE THE
THREAT FOR ELEVATED THUNDERSTORMS. STORMS WILL BE A MIX OF
WET AND DRY, AS PRECIPITABLE WATER INCREASES TO OVER 0.80". BUT AS
THE WAVE PUSHES INLAND, THE MIDLEVEL STEERING FLOW WILL INCREASE TO
OVER 30KTS. THIS INCREASED STORM SPEED WILL ALLOW FOR LESS RAINFALL
OVERALL AND HIGHER POTENTIAL FOR DRY LIGHTNING STRIKES. RED FLAG
WARNING IS IN EFFECT THROUGH 11 AM THIS MORNING FOR AREAS NORTH OF
TAHOE IN NORTHEASTERN CALIFORNIA AND THE NORTHEAST SIERRA. IT
STILL APPEARS THE BRUNT OF THE STORMS WILL REMAIN WEST OF THE
CREST THIS MORNING. SO FAR, LIGHTNING HAS BEEN LIMITED TO AROUND
LAKE OROVILLE. LATEST HRRR SHOWS STORMS TO INCREASE A BIT MORE
AFTER SUNRISE SO WILL LEAVE FORECAST ALONE FOR NOW.
THIS AFTERNOON CONVECTION WILL AGAIN DEVELOP IN NORTHWEST NEVADA
AND NORTHEAST CA. THESE STORMS WILL BE A MIX OF WET AND DRY STORMS
AS WELL, AS MID LEVEL FLOW REMAINS STRONGER.
THE NEXT THREAT FOR THUNDERSTORMS WILL BE MONDAY UNDER THE STRONG
RIDGE AND VERY HOT TEMPERATURES. THAT WILL BE THE BEST DAY FOR DRY
LIGHTNING DUE TO THE VERY HOT TEMPERATURES. BY TUESDAY/WEDNESDAY
MOISTURE WILL INCREASE WITH THE STORMS WET AND LOCALLY HEAVY RAINS
POSSIBLE. HOON/WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
311 AM PDT FRI JUL 11 2014
.SYNOPSIS...
ISOLATED TO SCATTERED THUNDERSTORMS FOR THE SIERRA AND WESTERN
NEVADA MAY CONTINUE NORTH OF SUSANVILLE AND GERLACH THIS MORNING.
ANOTHER ROUND OF STORMS IS POSSIBLE FROM NEAR INTERSTATE 80 NORTH
THIS AFTERNOON BEFORE HIGH PRESSURE STRENGTHENS OVER THE WEEKEND
FOR DRIER AND HOTTER CONDITIONS.
&&
.SHORT TERM...
EXPANDED COVERAGE OF THUNDERSTORMS SLIGHTLY FURTHER SOUTH FOR THIS
AFTERNOON AND EVENING. NO OTHER MAJOR CHANGES TO THE SHORT TERM
FORECAST.
AS OF 3 AM, WEAK ISOLATED-SCATTERED SHOWERS WERE MOVING NORTHWEST
ACROSS NORTHEASTERN CALIFORNIA AND NORTHWEST NEVADA MAINLY NORTH OF
HIGHWAY 50. WATER VAPOR IMAGERY ALSO SHOWED THE NEGATIVELY-TILTED
TROUGH JUST OFF THE CALIFORNIA COAST AND ITS ASSOCIATED JET
PUSHING INTO NORTHERN CALIFORNIA THIS MORNING. ISOLATED
THUNDERSTORMS AND LIGHTNING HAVE ALREADY BEGUN TO AFFECT AREAS
WEST OF THE CREST NEAR GRASS VALLEY AND REDDING EARLY THIS
MORNING. THUNDERSTORMS ARE EXPECTED TO BECOME MORE WIDESPREAD AS
FORCING/INSTABILITY PUSHES IN WITH THE TROUGH THROUGH THE MORNING.
FORECAST MODELS AND HIGH RESOLUTION FORECASTS (HRRR) STILL
INDICATING THAT THE BEST FORCING WILL FOCUS WEST OF THE SIERRA AND
ACROSS FAR NORTHERN CALIFORNIA AND SOUTHERN OREGON. WITH THE
POTENTIAL FOR ELEVATED CONVECTION ACROSS NORTHEASTERN CALIFORNIA
AND NORTHWEST NEVADA, DRY LIGHTNING AND POSSIBLE FIRE STARTS IS A
CONCERN. CHECK OUT THE FIRE WEATHER DISCUSSION FOR MORE DETAILS.
THE MAIN UPPER FORCING/JET NOSE SLIDES INTO EXTREME NORTHERN
NEVADA AND SOUTHEAST OREGON BETWEEN MID MORNING AND EARLY
AFTERNOON TODAY. WITH THE SLOWER TIMING OF THE INCOMING TROUGH AND
ITS UPPER LEVEL FORCING, WENT AHEAD AND SPREAD THE POTENTIAL FOR
ISOLATED THUNDERSTORMS FURTHER SOUTH FOR THIS AFTERNOON/EVENING.
THUNDERSTORMS WILL LIKELY FORM ALONG THE SIERRA AND THEN BE PUSHED
EASTWARD BY THE ZEPHYR WINDS IN THE AFTERNOON. KEPT THUNDERSTORMS
OUT OF TAHOE AND THE SIERRA FOR THIS REASON. OTHERWISE, INCREASING
SOUTHWEST FLOW ALOFT THROUGH THE DAY WILL GRADUALLY STABILIZE AND
DRY OUT THE ATMOSPHERE BY THE EVENING.
DRIER AND MORE STABLE AIR REALLY INVADES THE EASTERN SIERRA AND
WESTERN NEVADA BY SATURDAY AS THE FOUR CORNERS RIDGE BEGINS TO BUILD
WESTWARD INTO CALIFORNIA AND NEVADA. DAYTIME HIGHS ON SATURDAY WILL
BE NEAR OR SLIGHTLY ABOVE AVERAGE, BUT EXPECT TO SEE A SIGNIFICANT
WARMUP INTO NEXT WEEK. ELW
.LONG TERM...MONDAY THROUGH THURSDAY...
HIGH PRESSURE REMAINS OVER NEVADA NEXT WEEK WITH A DAILY THREAT OF
THUNDERSTORMS ALONG WITH ABOVE AVERAGE TEMPERATURES. THE MODELS,
ESPECIALLY THE GFS AND EC, REMAIN IN VERY GOOD AGREEMENT ON THIS.
GFS/EC NOW IN BETTER AGREEMENT WITH SOME MID-LEVEL COOLING WITH MORE
INSTABILITY MONDAY ALONG AND JUST EAST OF THE SIERRA CREST. WITH
MOISTURE STILL IN PLACE FROM THIS WEEK`S EVENT, THUNDERSTORMS ARE
POSSIBLE IN THIS AREA. TEMPERATURES WILL REMAIN HOT AND INTO THE
TRIPLE DIGITS IN WESTERN NEVADA AND 80S TO LOW 90S SIERRA. WITH THIS
BEING THE FIRST THUNDERSTORM DAY, A MIX OF WET AND DRY ARE POSSIBLE
WITH PW AROUND 0.8 INCHES. MONDAY WOULD BE THE BIGGEST CONCERN FOR
FIRE WEATHER.
ON TUESDAY INTO WEDNESDAY, THE HIGH SHIFTS A BIT FURTHER EAST INTO
EASTERN NEVADA WITH MOISTURE STREAMING UP FROM THE MONSOON. EXPECT
COVERAGE OF STORMS TO INCREASE WITH THE BEST DAY FOR STORMS LIKELY
WEDNESDAY. DAYTIME TEMPS WILL LIKELY SEE A COOLING TREND DUE TO
INCREASED CLOUD COVER.
ON THURSDAY, IT APPEARS A WEAK TROUGH WILL BEGIN TO MOVE INTO THE
PACNW CREATING A LIGHT SW FLOW. THIS SHOULD START A DRYING TREND SO
BEGAN TO TREND THE THREAT OF STORMS DOWNWARD. WALLMANN
&&
.AVIATION...
ISOLATED THUNDERSTORMS REMAIN POSSIBLE THIS MORNING, MAINLY NORTH OF
LAKE TAHOE INTO LASSEN COUNTY. BKN-OVC CIGS TO REMAIN NEAR 10 KFT.
THIS AFTERNOON, EXPECT MORE SHOWERS AND STORMS TO BE CONCENTRATED
NORTH OF I-80 WITH SFC WND GUSTS TO 40 KTS THE PRIMARY THREAT.
AFTERNOON SW WINDS ALSO LIKELY INTO THE RENO-TAHOE TERMINALS THIS
AFTERNOON WITH PEAK GUSTS 25 KTS 22-03Z. THIS WEEKEND LOOKS DRY WITH
THE NEXT THREAT OF THUNDERSTORMS NEXT WEEK. WALLMANN
&&
.FIRE WEATHER...
THIS MORNING, GOOD INSTABILITY ALOFT, STEEP UPPER LEVEL LAPSE RATES,
AND FORCING FROM THE MID AND UPPER-LEVEL WAVE WILL CONTINUE THE
THREAT FOR ELEVATED THUNDERSTORMS. STORMS WILL BE A MIX OF
WET AND DRY, AS PRECIPITABLE WATER INCREASES TO OVER 0.80". BUT AS
THE WAVE PUSHES INLAND, THE MIDLEVEL STEERING FLOW WILL INCREASE TO
OVER 30KTS. THIS INCREASED STORM SPEED WILL ALLOW FOR LESS RAINFALL
OVERALL AND HIGHER POTENTIAL FOR DRY LIGHTNING STRIKES. RED FLAG
WARNING IS IN EFFECT THROUGH 11 AM THIS MORNING FOR AREAS NORTH OF
TAHOE IN NORTHEASTERN CALIFORNIA AND THE NORTHEAST SIERRA. IT
STILL APPEARS THE BRUNT OF THE STORMS WILL REMAIN WEST OF THE
CREST THIS MORNING. SO FAR, LIGHTNING HAS BEEN LIMITED TO AROUND
LAKE OROVILLE. LATEST HRRR SHOWS STORMS TO INCREASE A BIT MORE
AFTER SUNRISE SO WILL LEAVE FORECAST ALONE FOR NOW.
THIS AFTERNOON CONVECTION WILL AGAIN DEVELOP IN NORTHWEST NEVADA
AND NORTHEAST CA. THESE STORMS WILL BE A MIX OF WET AND DRY STORMS
AS WELL, AS MID LEVEL FLOW REMAINS STRONGER.
THE NEXT THREAT FOR THUNDERSTORMS WILL BE MONDAY UNDER THE STRONG
RIDGE AND VERY HOT TEMPERATURES. THAT WILL BE THE BEST DAY FOR DRY
LIGHTNING DUE TO THE VERY HOT TEMPERATURES. BY TUESDAY/WEDNESDAY
MOISTURE WILL INCREASE WITH THE STORMS WET AND LOCALLY HEAVY RAINS
POSSIBLE. HOON/WALLMANN
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...RED FLAG WARNING UNTIL 11 AM PDT THIS MORNING CAZ271-278.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS TAUNTON MA
656 AM EDT FRI JUL 11 2014
.SYNOPSIS...
TRANQUIL WEATHER TODAY AND TOMORROW AS HIGH PRESSURE SETTLES OVER
THE REGION. UNSETTLED WEATHER IN THE FORM OF SHOWERS AND
THUNDERSTORMS RETURNS LATE SUNDAY INTO EARLY NEXT WEEK. THERE IS
THE POTENTIAL FOR STRONG WINDS AND HEAVY RAINFALL.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
7 AM UPDATE....
COLD FRONT IS NOW SOUTH OF NANTUCKET WITH ALL LOCATIONS REPORTING
N TO NE WINDS. DRIER/LESS HUMID AIRMASS BEGINNING TO STREAM ACROSS
THE REGION WITH DEW PTS NOW IN THE 50S...EXCEPT STILL IN THE 60S
CLOSER TO THE FRONT ACROSS THE SOUTH COAST. MID LEVEL TROUGH
REMAINS WEST OF NEW ENGLAND AND AS A RESULT SW FLOW ALOFT PREVAILS
ACROSS THE REGION. THIS IS RESULTING IN MID AND HIGH CLOUDS MOVING
ACROSS EASTERN CT/RI AND EASTERN MA. HOWEVER BACK EDGE OF THIS
CLOUD SHIELD IS FROM AROUND HARTFORD CT NORTHEAST TO MANCHESTER NH
AND MOVING STEADILY EASTWARD. THUS EXPECT DECREASING CLOUDS AS THE
MORNING PROGRESSES. SOME OF THE GUIDANCE INCLUDING THE HRRR HINTS
AT THE POTENTIAL FOR A FEW AFTERNOON SHOWERS AS THE MID LEVEL
TROUGH MOVES THRU THE REGION. HOWEVER A CLOSER INSPECTION OF THE
GUID INDICATES MID LEVEL DRY AIR BECOMES DEEPER AS THE DAY
PROGRESSES. THIS SHOULD PRECLUDE SHOWER DEVELOPMENT AND ONLY YIELD
SOME MODERATE BUILDUPS. PREVIOUS FORECAST HANDLES THIS WELL SO NO
MAJOR CHANGES EXPECTED WITH THIS UPDATE. EARLIER DISCUSSION BELOW.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
RAIN SHIELD CONTINUES TO MOVE NORTHEASTWARD AND HAS DROPPED SOME
PRECIP ACROSS MVY EARLY THIS MORNING. BELIEVE THAT ACK WILL ALSO
GET CLIPPED WITHIN THE HOUR AS RAIN SHOWERS CONTINUE TO MOVE OVER
THE REGION. STATIONARY FRONT IS STILL STRADDLING JUST SOUTH OF THE
MAINLAND...PER SURFACE DEWPOINT OBSERVATIONS. THIS FRONT WILL
CONTINUE A VERY SLOW SOUTHWARD MOVEMENT THROUGH OUT THE DAY.
CIRRUS SHIELD HAS REALLY LIMITED ANY RADIATIONAL COOLING EARLY
THIS MORNING SO BELIEVE THAT MIN TEMPS WILL REMAIN STEADY OVER
THE NEXT FEW HOURS. OTHERWISE A PRETTY QUIET NIGHT WITH COMFORTABLE
CONDITIONS.
TODAY...
HIGH PRESSURE WILL BUILD OVER THE REGION TODAY WITH THE STALLED
FRONT STILL LINGERING TO THE SOUTH. ALTHOUGH THE LOW LEVELS WILL BE
DRY...SOME INCREASE MOISTURE IN THE MID TO UPPER LEVELS WILL PRODUCE
SOME DIURNAL CU THIS AFTERNOON. SOME OF THE MODEL GUIDANCE IS STILL
TRYING TO SQUEEZE OUT SOME QPF TODAY AS UPPER LEVEL JET MOVES OVER
THE REGION PROVIDING SOME LIFT. BECAUSE THERE IS A GOOD AMOUNT OF
DRY AIR IN THE LOW LEVELS PER SOUNDINGS...KEPT A DRY FORECAST.
TEMPERATURES WILL CONTINUE TO BE COOLER THEN THE START OF THE WORK
WEEK WITH HIGHS REACHING IN THE LOW TO MID 80S. SEA BREEZES WILL
DEVELOP ALONG BOTH COASTLINES KEEPING COASTAL AREAS IN THE 70S.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM SATURDAY/...
TONIGHT...
HIGH PRESSURE WILL CONTINUE TO DOMINATE ACROSS SOUTHERN NEW ENGLAND
TONIGHT. THIS WILL ALLOW FOR A WEAK PRESSURE GRADIENT AND WITH
MOSTLY CLEAR SKIES COULD SEE SOME RADIATIONAL COOLING. TEMPS WILL
GENERALLY BE IN THE UPPER 50S WITH LOW 60S ACROSS THE METRO REGIONS.
PATCHY FOG MAY DEVELOP ESPECIALLY ACROSS VALLEY REGIONS BUT HAVE
A LOWER CONFIDENCE.
TOMORROW...
HIGH PRESSURE WILL BEGIN TO SLIDE EASTWARD ON SATURDAY. MOISTURE
WILL SLOWLY INCREASE AS WINDS WILL SWITCH TO THE SOUTHWEST NEAR THE
END OF THE DAY. THIS WILL ALLOW FOR MORE DIURNAL CU TO DEVELOP.
STILL A PRETTY WEAK PRESSURE GRADIENT SO SEA BREEZE DEVELOPMENT
LOOKS LIKELY ALONG BOTH COASTLINES.
FULL MOON WILL OCCUR OVER THE WEEKEND ALLOWING FOR THE
ASTRONOMICAL HIGH TIDES TO OCCUR. THERE COULD BE SOME MINOR
SPLASHOVER ACROSS SCITUATE AND P-TOWN HARBOR. OTHERWISE EXPECT
VERY LITTLE IMPACT ON THE LATE SATURDAY HIGH TIDE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGHLIGHTS...
* MORE HUMID AND BREEZY SUNDAY...SHOWERS POSSIBLE LATE
* STRONG TO SEVERE THUNDERSTORMS & HEAVY RAINFALL POSSIBLE MON/TUE
* TREND TOWARD DRIER AND LESS HUMID WEATHER MID TO LATE NEXT WEEK
SYNOPTIC OVERVIEW AND MODEL PREFERENCES...
GUIDANCE CONTINUES TO SIMULATE AN EVOLVING HIGHLY ANOMALOUS
AMPLIFIED NORTHERN STREAM THIS PERIOD WITH A FULL LATITUDE RIDGE
DEVELOPING ACROSS THE WESTERN CONUS INTO CANADA. DOWNSTREAM A POTENT
CLOSED LOW ADVECTS SOUTHWARD INTO THE GREAT LAKES EARLY NEXT WEEK.
THIS YIELDS A DEEP MOIST SW FLOW ALONG THE EASTERN SEABOARD WITH AN
INFLUX OF GULF AND ATLANTIC MOISTURE INTO NEW ENGLAND. A STRONG
FRONTAL ZONE WILL ACCOMPANY THIS CLOSED LOW AND WILL BECOME THE
FOCUS FOR CONVECTION AND HEAVY RAINFALL EARLY NEXT WEEK ACROSS NEW
ENGLAND. ANOMALOUS JET DYNAMICS ASSOCIATED WITH THIS FEATURE
COMBINED WITH PEAK CLIMATOLOGICAL HEATING WILL INCREASE THE RISK FOR
STRONG TO SEVERE STORMS HERE IN SOUTHERN NEW ENGLAND. ALSO GIVEN THE
DEEP SOUTHWEST FLOW THESE STORMS WILL HAVE THE POTENTIAL OF BACK
BUILDING AND TRAINING OVER THE SAME AREA YIELDING A RISK OF FLASH
FLOODING. AS FOR MODEL GUIDANCE...BOTH THE 12Z GEFS AND ECENS
ENSEMBLES ALONG WITH THE 00Z DETERMINISTIC RUNS OF GFS AND ECMWF ARE
IN VERY GOOD AGREEMENT ON TROUGH/RIDGE AMPLITUDE AND TIMING OF
FRONTAL PASSAGE. THUS WILL BLEND ALL DATA SOURCES FOR THIS PORTION
OF THE FORECAST.
DAILY DETAILS...
SAT NIGHT...
QUIET/DRY WEATHER AS HIGH PRES LINGERS ALONG THE COAST. SEASONABLE
TEMPS WITH LOWS IN THE LOW TO MID 60S. TOLERABLE HUMIDITY WITH DEW
PTS IN THE U50S TO L60S.
SUNDAY...
BECOMING MORE HUMID AND BREEZY AS LOW LEVEL WARM AIR ADVECTION
INCREASES AS SURFACE HIGH DRIFTS OFFSHORE. NICE WEATHER LINGERS MUCH
OF THE DAY ACROSS EASTERN NEW ENGLAND PER GOOD MODEL AGREEMENT ON
WARM ADVECTION PRECIP ARRIVING AFTER 18Z ACROSS WESTERN NEW ENGLAND
AND PROBABLY NOT UNTIL AFTER 00Z OVER RI AND EASTERN MA. THUS DRY
WEATHER FOR MUCH OF THE DAYLIGHT HOURS ACROSS RI AND EASTERN MA.
EARLY NEXT WEEK...
WARM AND MUGGY CONDITIONS AHEAD OF A STRONG FRONTAL BOUNDARY
APPROACHING THE REGION FROM THE WEST. AS MID LEVEL FLOW AMPLIFIES
AND BACKS...DEEP S-SW FLOW ALOFT DEVELOPS ALONG THE EASTERN
SEABOARD. THIS RESULTS IN A SLOW MOVING FRONTAL BOUNDARY WITH AN
INFLUX OF GULF AND ATLC MSTR. STRONG JET DYNAMICS COUPLED WITH AT
LEAST MODEST INSTABILITY INCREASES THE RISK OF STRONG TO SEVERE
STORMS ALONG AND AHEAD OF THE APPROACHING FRONT MON AND TUE. IN
ADDITION THE DEEP S-SW FLOW ALOFT WILL PROVIDE AN ENVIRONMENT
FAVORABLE FOR BACK BUILDING STORMS AND TRAINING OVER THE SAME AREA.
THUS A RISK OF FLASHING FLOODING.
MID TO LATE NEXT WEEK...
ENSEMBLES AND DETERMINISTIC GUIDANCE SUGGEST A FRONTAL PASSAGE
AROUND WED ALONG WITH MID TO UPPER TROUGH DEAMPLIFYING AS IT LIFTS
NE INTO ONTARIO AND QUEBEC. THIS SUPPORTS A TREND TOWARD DRIER AND
LESS HUMID WEATHER MID TO LATE NEXT WEEK.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY/...HIGH CONFIDENCE.
7 AM UPDATE...NO MAJOR CHANGES FROM 06Z TAFS. MVFR VSBYS IN PATCHY
SHALLOW FOG OVER CAPE COD AND THE ISLANDS WILL IMPROVE TO VFR BY
15Z. EARLIER DISCUSSION BELOW.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TODAY TIL TOMORROW...VFR THROUGH THE PERIOD. SEA BREEZES ONCE
AGAIN LIKELY AT NEAR SHORE TERMINALS FOR TODAY AND TOMORROW.
LOW CONFIDENCE ON PATCHY FOG ACROSS THE SOUTH COASTLINE.
KBOS TAF...HIGH CONFIDENCE IN TAF. SEA BREEZE SHOULD START 13-15Z
TODAY.
KBDL TAF...HIGH CONFIDENCE IN TAF.
OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY...
SATURDAY NIGHT...HIGH CONFIDENCE FOR VFR AND DRY WEATHER.
SUNDAY...VFR BUT LOW RISK OF MVFR LATE IN THE DAY WESTERN NEW
ENGLAND AS SHOWERS ENTER THIS AREA. HIGH CONFIDENCE ON TRENDS BUT
LOWER CONFIDENCE ON EXACT TIMING.
SUNDAY NIGHT THROUGH TUESDAY...LOW TO MODERATE CONFIDENCE. MAINLY
VFR DURING THE DAYLIGHT HOURS BUT LOWERING TO MVFR/IFR AT NIGHT IN
AREAS OF FOG. ALSO MVFR IN SCT SHOWERS/TSTMS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /TODAY THROUGH SATURDAY/...HIGH CONFIDENCE.
A COLD FRONT WILL SLOWLY MOVE SOUTH OF THE WATERS TODAY AND
TOMORROW. A FEW ISOLATED SHOWERS MAY OCCUR TODAY BUT DRY WEATHER
SHOULD PREVAIL BY THE AFTERNOON LASTING THROUGH THE PERIOD. WINDS
AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS THROUGH
SATURDAY.
OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY...
SATURDAY NIGHT...QUIET BOATING WEATHER WITH LIGHT SSW WINDS AND DRY
WEATHER.
SUNDAY...SSW WINDS INCREASE AS FRONT APPROACHES. SHOWERS/TSTMS HOLD
OFF UNTIL SUN NIGHT.
MON AND TUE...PERSISTENT MODEST SSW WINDS 15-20 KT WITH HIGHER
GUSTS. SCT TSTMS WITH HEAVY RAIN AND STRONG WINDS POSSIBLE. PATCHY
DENSE FOG POSSIBLE ESPECIALLY AT NIGHT AND EARLY MORNING.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA/DUNTEN
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...NOCERA
AVIATION...NOCERA/DUNTEN
MARINE...NOCERA/DUNTEN
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1018 AM EDT FRI JUL 11 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD ACROSS THE NORTHEAST STATES TODAY, THEN
SHIFT OFFSHORE LATER TONIGHT AND SATURDAY. A WARM FRONT SHOULD
LIFT NORTH OF THE REGION SUNDAY, THEN A COLD FRONT IS FORECAST TO
ARRIVE LATE MONDAY NIGHT AND ESPECIALLY TUESDAY. THIS FRONT SHOULD
BE SETTLING TO OUR SOUTH AND EAST WEDNESDAY, AS HIGH PRESSURE
GRADUALLY ARRIVES FROM THE WEST DURING THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE SFC FRONTAL BOUNDARY THAT STALLED OVER THE DELMARVA YESTERDAY
HAS FINALLY MOVED SOUTH AND EAST OF THE REGION THIS MORNING. A BROAD
SFC HIPRES OVER UPSTATE NY WILL BUILD EWD INTO NEW ENGLAND TODAY.
LIGHT NELY FLOW AROUND THE HIGH THIS MORNING HAS BEEN ASSOCIATED
WITH MARINE STRATUS ALONG THE SRN NJ COAST/DELMARVA. STRATUS IS
ALREADY MIXING OUT QUICKLY DURING THE MID MORNING IN SRN NJ AND NRN
DELAWARE BUT FARTHER SOUTH, WHERE THE 925 MB COLD FRONT HAS LAGGED
BEHIND THE SFC BOUNDARY AND LLVL MOISTURE HAS POOLED, LOW CLOUDS
WILL TAKE LONGER TO ERODE FROM NORTH TO SOUTH.
SEVERAL HIRES MODELS SHOW POP UP SHOWERS AND STORMS DEVELOPING IN
EXTREME SERN PA AND OVER THE DELMARVA THIS AFTN DURING THE PEAK
HEATING HRS. THIS APPEARS TO BE WHERE THE HIGHER MOISTURE RESIDES
WITH SFC DEWPOINTS IN THE UPPER 60S VS UPPER 50S/LOWER 60S FARTHER
NORTH). LIFT WOULD BE ATTRIBUTED TO AN APPROACHING SHORTWAVE TROUGH
AXIS AND EVEN THE RUC SHOWS SFC CONVERGENCE DEVELOPING NEAR THE ERN
SHORE OF THE CHSPK BAY AROUND 18Z. THE FORCING WILL BE WEAK THOUGH,
FAVORING MINIMAL CONVECTIVE COVERAGE. INSTABILITY/SHEAR PROFILES NOT
INDICATIVE OF A SEVERE THREAT, BUT CANNOT RULE OUT AN ISO STRONG
STORM DEVELOP OVER THE DELMARVA.
MAX TEMPS TODAY IN THE LOW TO MID 80S EXCEPT 5-10F COOLER ALONG THE
COAST AND IN THE POCONOS. MAY NEED TO LOWER TEMPS A COUPLE OF
DEGREES IN THE CENTRAL DELMARVA IF LOW CLOUDS HOLD ON A BIT LONGER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE MID LEVEL TROUGH IS FORECAST TO MOVE TO OUR EAST TONIGHT. ANY
ISOLATED PRECIPITATION EARLY THIS EVENING SHOULD DISSIPATE QUICKLY
AS THE ATMOSPHERE CONTINUES TO TO STABILIZE AND AS HIGH PRESSURE
BUILDS INTO OUR REGION FROM THE NORTH.
THE SKY IS EXPECTED TO BE MOSTLY CLEAR FOR TONIGHT AND THE WIND
SHOULD BECOME LIGHT AND VARIABLE. THE COMBINATION IS ANTICIPATED TO
ALLOW TEMPERATURES TO FALL INTO THE UPPER 50S TO MIDDLE 60S IN MUCH
OF OUR REGION.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
THE OVERALL SYNOPTIC SETUP IS COMPRISED OF A POTENT UPPER-LEVEL
TROUGH THAT CLOSES OFF AS IT DIGS ACROSS THE MIDWEST AND GREAT LAKES
REGION SUNDAY AND MONDAY, THEN BEGINS TO SHIFT INTO PORTIONS OF THE
NORTHEAST TUESDAY AND WEDNESDAY. THIS FEATURE WILL DRIVE A COLD
FRONT ACROSS OUR AREA IN THE TUESDAY INTO WEDNESDAY TIME FRAME WITH
CONVECTIVE EPISODES AHEAD OF IT. THERE IS THE POTENTIAL FOR STRONG
TO SEVERE THUNDERSTORMS TO OCCUR ESPECIALLY TUESDAY AS THE MAIN
FEATURES ALOFT MOVE THROUGH. WE USED A MODEL BLEND FOR SATURDAY INTO
MONDAY, THEN MOSTLY BLENDED THE 00Z WPC GUIDANCE INTO CONTINUITY
THEREAFTER.
FOR SATURDAY AND SUNDAY...AS THE CENTER OF HIGH PRESSURE SHIFTS
FARTHER OFFSHORE SATURDAY, THE FLOW WILL TURN FROM EAST-SOUTHEAST TO
MORE SOUTHERLY. AS THIS OCCURS, SOME INCREASE IN THE WAA AHEAD OF AN
AMPLIFYING UPPER-LEVEL TROUGH INTO THE GREAT LAKES REGION SHOULD
ORGANIZE A WARM FRONT TO OUR SOUTHWEST. THIS FRONT SHOULD THEN START
MIGRATING NORTHWARD SUNDAY. OVERALL SATURDAY LOOKS TO BE DRY WITH
HIGH PRESSURE CLOSE ENOUGH TO START AND THEN OVERALL A LACK OF
ORGANIZED LIFT. IF ISOLATED CONVECTION WHERE TO FORM IN THE
AFTERNOON, IT SHOULD BE TO OUR WEST ON THE PERIPHERY OF THE SURFACE
HIGH AND CLOSER TO THE TERRAIN INFLUENCES. AS THE UPPER-LEVEL FLOW
STARTS TO TURN MORE CYCLONIC SUNDAY, SOME SHOWERS AND THUNDERSTORMS
SHOULD DEVELOP MAINLY INLAND IN THE AFTERNOON PERHAPS FOCUSED NEAR A
LEE SIDE TROUGH. THIS WOULD BREAK OUR STRING OF NICE WEATHER ON THE
WEEKENDS AT LEAST FOR A PORTION OF OUR CWA.
FOR MONDAY THROUGH WEDNESDAY...A ROBUST UPPER-LEVEL TROUGH/CLOSED
LOW FOR THIS TIME OF THE YEAR IS FORECAST TO SLIDE ACROSS THE GREAT
LAKES REGION AND TOWARD THE NORTHEAST. LOW PRESSURE TRACKING ACROSS
CANADA WILL PULL A COLD FRONT INTO THE EAST LATER TUESDAY INTO
WEDNESDAY. THE PRESENCE OF STRENGTHENING CYCLONIC FLOW IN
COMBINATION WITH AN INCREASINGLY UNSTABLE AIRMASS WILL INITIATE
SHOWERS AND THUNDERSTORMS. THIS MAY BE TIED TO AN INITIAL LEE SIDE
TROUGH MONDAY WITH MORE OF A CONVECTIVE ORGANIZATION ACROSS OUR
WESTERN ZONES, THEN MORE FOCUSED TUESDAY WITH THE COLD FRONT /ALSO A
PRE-FRONTAL TROUGH/ ALONG WITH SOME COOLING ALOFT AND STRONGER FLOW.
THE INSTABILITY SHOULD BE ENHANCED SOME AS DEEPER MOISTURE ADVECTS
NORTHEASTWARD IN ADVANCE OF THE SURFACE FRONT. IT WILL BE WARM AND
HUMID AS WELL, AND MONDAY LOOKS TO BE THE HOTTEST DAY AS THE
LOW-LEVEL WAA SHOULD PEAK. AS OF NOW, WE ARE NOT ANTICIPATING ANY
HEAT RELATED HAZARDS ACROSS THE CWA.
THE LARGE SCALE LIFT IS FORECAST TO INCREASE SUBSTANTIALLY TUESDAY
WITH THE PRESENCE OF A STRONG SHORT WAVE SLIDING ACROSS THE REGION.
THIS COULD RESULT IN SOME STRONG TO SEVERE CONVECTIVE EPISODES
MONDAY AND PARTICULARLY ON TUESDAY. WHILE THERE IS LESS CERTAINTY
WITH THE DETAILS, THE POTENTIAL IS THERE FOR SEVERE THUNDERSTORMS.
BASED ON THE FORECAST SOUNDINGS, IT APPEARS THAT LINE SEGMENTS WITH
EMBEDDED BOWING STRUCTURES WOULD BE THE MAIN STORM MODE GIVEN A MORE
UNIDIRECTIONAL FLOW THROUGH THE COLUMN. THE CONVECTION THAT OCCURS
ON MONDAY MAY HAVE AN IMPACT ON WHAT DEVELOPS ON TUESDAY. THE PW
VALUES ARE FORECAST TO INCREASE TO AROUND 2 INCHES MONDAY AND
TUESDAY, WHICH WILL ALLOW FOR LOCALLY HEAVY RAIN TO OCCUR. THIS
COULD ALSO INCREASE THE THREAT FOR WATER LOADED DOWNDRAFTS. WE WILL
MAINTAIN A MENTION IN THE HAZARDOUS WEATHER OUTLOOK.
THE COLD FRONT SHOULD BE EASING TO OUR SOUTH AND EAST DURING
WEDNESDAY, WITH DRYING ARRIVING FROM THE NORTHWEST. THERE COULD BE
SOME CONVECTION LINGERING TO START ACROSS OUR EASTERN ZONES, AND
THEREFORE MUCH OF THE REGION WAS KEPT DRY.
FOR THURSDAY...A LARGE UPPER-LEVEL TROUGH IS FORECAST TO BE IN
PLACE, HOWEVER THE CENTER OF IT LOOKS TO BE NORTH OF THE GREAT
LAKES. THIS WILL MAINTAIN CYCLONIC FLOW ACROSS OUR AREA AS SURFACE
HIGH PRESSURE GRADUALLY BUILDS IN FROM THE WEST. WE ARE ANTICIPATING
A COOLER AIRMASS TO BE IN PLACE ALONG WITH LOWER DEW POINTS. NO
MAJOR CHANGES WERE MADE TO THIS TIME FRAME.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
EARLIER LOW CLOUDS AT MIV/ACY DISSIPATED BETWEEN 12-13Z THIS MRNG.
VFR TODAY, BUT AN ISO POP UP SHRA/TSRA POSSIBLE IN SOUTHWESTERN AREA
TERMINALS. THE BEST CHANCE TO SEE THIS ACTIVITY WOULD BE ILG, BUT
COVERAGE TOO LOW TO INCLUDE IN 12Z TAFS. NE WINDS 5-10 KT TDA WILL
BECOME SELY THIS EVE AROUND 5 KT.
OUTLOOK...
SATURDAY...PERHAPS LOCAL MVFR/IFR STRATUS OR FOG TO START,
OTHERWISE VFR. SOUTHERLY WINDS MAINLY 5-10 KNOTS.
SUNDAY AND MONDAY...TIMES OF SUB-VFR WITH SOME SHOWERS AND
THUNDERSTORMS AROUND. THE BEST CHANCE APPEARS TO BE FOR THE FARTHER
INLAND TERMINALS EACH AFTERNOON AND EVENING.
TUESDAY...A BETTER CHANCE FOR ORGANIZED SHOWERS AND THUNDERSTORMS AS
A COLD FRONT ARRIVES. SOME STORMS MAY PRODUCE GUSTY SURFACE WINDS.
&&
.MARINE...
THE FRONTAL BOUNDARY WILL CONTINUE TO SINK TO OUR SOUTH TODAY,
ALLOWING HIGH PRESSURE FROM THE NORTH TO BUILD ACROSS THE COASTAL
WATERS OF NEW JERSEY AND DELAWARE FOR TONIGHT. NE WINDS AROUND
10-15 KT ARE OCCURRING OVER THE COASTAL ATLANTIC WATERS THIS MRNG.
THESE WINDS WILL DECREASE BY LATE AFTN. LIGHT AND VARIABLE WINDS
TNGT.
WIND SPEEDS AND WAVE HEIGHTS ARE ANTICIPATED TO REMAIN BELOW THE
SMALL CRAFT ADVISORY CRITERIA FOR TODAY AND TONIGHT.
OUTLOOK...
SATURDAY...HIGH PRESSURE NEAR THE NEW ENGLAND COAST WILL SHIFT
FARTHER OFFSHORE. THIS WILL RESULT IN THE FLOW TURNING MORE
SOUTHERLY WITH TIME, HOWEVER IT IS ANTICIPATED TO BE LIGHT.
SUNDAY THROUGH TUESDAY...THE FLOW BECOMES MORE SOUTHWESTERLY ON
SUNDAY. THESE WINDS STRENGTHEN MONDAY AND TUESDAY AHEAD OF A COLD
FRONT, HOWEVER THEY SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA. IF ENOUGH MIXING OCCURS ON TUESDAY, SOME MARGINAL ADVISORY
GUSTS CAN OCCUR ESPECIALLY NEARSHORE. THE SOUTHERLY FLOW WILL BUILD
THE SEAS AND AN ADVISORY MAY BE NEEDED MONDAY AND TUESDAY FOR THE
COASTAL WATER ZONES. THE WAVEWATCH GUIDANCE HOWEVER COULD BE
OVERDONE GIVEN THE SOUTHERLY FLOW WITHIN A WAA REGIME. SOME SHOWERS
AND THUNDERSTORMS ARE ANTICIPATED MONDAY AND TUESDAY, SOME WITH
POTENTIALLY GUSTY WINDS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...KLEIN
SHORT TERM...IOVINO
LONG TERM...GORSE
AVIATION...GORSE/IOVINO/KLEIN
MARINE...GORSE/IOVINO/KLEIN
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
707 AM EDT FRI JUL 11 2014
.SYNOPSIS...
A WEAK STATIONARY FRONT WILL DISSIPATE NORTH OF THE AREA THROUGH
TONIGHT. ATLANTIC HIGH PRESSURE WILL BUILD IN OVER THE WEEKEND
INTO EARLY NEXT WEEK. THEN...A COLD FRONT WILL SLOWLY MOVE
SOUTHEAST THROUGH THE REGION TUESDAY THROUGH THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY FRIDAY MORNING...SOME HIGH RESOLUTION GUIDANCE INCLUDING THE
RUC13 AND THE HRRR SUGGEST THAT THE ONSET OF DIURNAL CONVECTION
COULD BE DELAYED A COUPLE OF HOURS INTO EARLY/MID AFTERNOON. GIVEN
THE PLUME OF PWATS AROUND 2 INCHES OVER THE REGION...HIGHEST
ALONG THE COAST...STILL FEEL THAT CONVECTION WILL BEGIN TO FIRE
BY LATE MORNING/MIDDAY. PER EARLY MORNING RADAR TRENDS AND TO
ACCOUNT FOR THE SUBTLE MODEL TREND TOWARD A SLIGHTLY LATER ONSET
OF THUNDERSTORMS... ADJUSTED HOURLY POPS THIS MORNING. OTHERWISE...
OVERALL FORECAST REASONING HAS NOT CHANGED.
EXPECT AN ACTIVE CONVECTION REGIME ACROSS THE FORECAST
AREA TODAY...PERHAPS FEATURING GREATER OVERALL COVERAGE AS
COMPARED WITH THURSDAY PM.
AS THE ENVIRONMENT WARMS/DESTABILIZES BY LATE MORNING/MIDDAY
ADDITIONAL SHOWERS/THUNDERSTORMS SHOULD READILY DEVELOP ALONG VARIOUS
BOUNDARIES...INCLUDING THE SEA BREEZE NEAR THE COAST AND
OUTFLOW LEFT BY OVERNIGHT CONVECTION ACROSS INLAND COUNTIES. THEN...
CONVECTION WILL INCREASE IN COVERAGE AS A COMPLEX OUTFLOW BOUNDARY
REGIME DEVELOPS THROUGH THE AFTERNOON.
MODEL GUIDANCE DIFFERS REGARDING THE FOCUS OF GREATEST
SHOWER/THUNDERSTORM COVERAGE. SOME GUIDANCE DEPICTS HIGHEST POPS
NEAR THE COAST...WHILE OTHER GUIDANCE DEPICTS GREATEST COVERAGE
INLAND AND STILL OTHER GUIDANCE MORE OR LESS SPLITS THE
DIFFERENCE. THE EARLY FRIDAY MORNING FORECAST INDICATES MAX POPS
HIGH CHANCE TO LIKELY...HIGHEST IN A SWATH CENTERED AROUND THE
I-95 CORRIDOR THIS AFTERNOON/EARLY EVENING.
HIGH PWATS AND THE POTENTIAL FOR BOUNDARY INTERACTIONS/LOCALLY
ENHANCED UPDRAFTS SUGGESTS A CHANCE FOR THE USUAL/ISOLATED PULSE
SEVERE EPISODES FEATURING DAMAGING WET MICROBURSTS. OF GREATER
CONCERN...PWATS EXCEEDING 2 INCHES AND THE POTENTIAL FOR
ERRATIC/SLOW THUNDERSTORM PROPAGATION WILL PRESENT THE CHANCE FOR
LOCALLY EXCESSIVE RAINFALL. WILL HIGHLIGHT THE POTENTIAL FOR
LOCALLY HEAVY RAIN WITHIN THE HAZARDOUS WEATHER OUTLOOK AND WILL
MENTION HEAVY RAIN WITHIN PUBLIC PRODUCTS.
CLOUDS/PRECIPITATION SHOULD HOLD TEMPERATURES BELOW LEVELS OF THE
PAST FEW DAYS...PERHAPS FALLING SHORT OF 90F AT KCHS/KSAV IF
THUNDERSTORMS FIRE EARLY. HOWEVER...WHERE THUNDERSTORMS ARE DELAYED
OR DO NOT OCCUR...TEMPERATURES SHOULD TOP OUT IN THE LOWER 90S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
THE ACTIVE CONVECTIVE REGIME SHOULD CONTINUE INTO THIS
EVENING...ESPECIALLY ACROSS SOUTHERN/INLAND COUNTIES...THEN
DIURNAL/PRECIPITATION STABILIZATION SHOULD TRANSLATE TO DIMINISHING
SHOWER/THUNDERSTORM COVERAGE. THEN...SOME GUIDANCE DEPICTS AN UPTICK
IN CONVECTION OVERNIGHT...ESPECIALLY EAST OF I-95/ALONG THE COAST
AND OVER ADJACENT COASTAL WATERS.
IF PRECIPITATION COVERAGE IS SUFFICIENT...PERHAPS PATCHY GROUND FOG
AND EVEN SOME STRATUS WILL DEVELOP OVERNIGHT. OTHERWISE...TEMPS
SHOULD BOTTOM OUT IN THE LOWER TO MID 70S MOST AREAS.
A BROAD UPPER LEVEL RIDGE WILL EXPAND TO THE EAST ON SATURDAY WHILE
SURFACE HIGH PRESSURE BUILDS IN FROM THE NORTH. THE DRIER LOW-LEVEL
AIR LOOKS TO STAY JUST TO OUR NORTH...WHILE WE MAINTAIN 70+ SURFACE
DEWPOINTS IN PLACE WITH AN ONSHORE FLOW. A WEAK SURFACE TROUGH
ACROSS SOUTHEAST GA...COMBINED WITH A CONSIDERABLE SEA BREEZE AND
INCREASING MOISTURE CONVERGENCE SHOULD YIELD SCATTERED SHOWERS AND
THUNDERSTORMS MAINLY DURING THE AFTERNOON. SLIGHTLY WARMER MID
LEVELS AND LESS CONVERGENCE ACROSS SOUTHERN SC MAY MAKE FOR MORE
ISOLATED COVERAGE. INLAND HIGHS WILL REACH THE LOWER 90S WHILE AREAS
CLOSER TO THE COAST MAY STRUGGLE TO HIT 90 DUE TO THE PREVAILING
ONSHORE FLOW.
BROAD UPPER RIDGING PERSISTS ON SUNDAY WHILE ATLANTIC HIGH PRESSURE
REBUILDS TO OUR EAST. DEEP LAYERED FLOW BECOMES SOUTHERLY DURING THE
AFTERNOON THOUGH A WEAK SURFACE TROUGH WILL PERSIST ACROSS SOUTHEAST
GA. MODELS SHOW THE GREATEST LOW-LEVEL INSTABILITY AGAIN ACROSS
INTERIOR SOUTHEAST GA COINCIDENT WITH THE TROUGH. SCATTERED SHOWERS
AND THUNDERSTORMS EXPECTED DURING THE HOURS OF PEAK HEATING...
ESPECIALLY INTERIOR AREAS WHERE THE SEA BREEZE ENCOUNTERS MODERATE
INSTABILITY DURING THE AFTERNOON. SLIGHT INCREASE IN HEIGHTS AND A
LATER SEA BREEZE SHOULD ALLOW FOR WARM TEMPS IN THE LOWER TO MIDDLE
90S.
THE UPPER RIDGE BREAKS DOWN SLIGHTLY ON MONDAY WITH LOW AND MID
LEVEL FLOW BECOMING MORE WEST TO SOUTHWESTERLY. AS THE ATLANTIC HIGH
BUILDS THE INLAND TROUGH SHOULD DISSIPATE. ALTHOUGH WE LOSE THE
SYNOPTIC SCALE CONVERGENCE AXIS...MOISTURE ADVECTION WILL PUSH PWATS
ABOVE 2.1 INCHES DURING THE AFTERNOON AND THICKNESSES WILL ALLOW
TEMPS TO RISE INTO THE LOW TO MIDDLE 90S YET AGAIN. THUS WE STILL
EXPECT SCATTERED SHOWERS AND TSTMS TO DEVELOP MAINLY DURING THE
AFTERNOON AND EVENING...ESPECIALLY ONCE THE SEA BREEZE SETS UP.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
MUCH OF NEXT WEEK WILL BE DOMINATED BY AN UNSEASONABLY STRONG UPPER
LEVEL TROUGH ACROSS THE CENTRAL UNITED STATES. A VERY DEEP SWLY FLOW
WILL PRECEDE A SLOW-MOVING COLD FRONT EXPECTED TO DRIFT THROUGH THE
AREA TUESDAY INTO WEDNESDAY. MODELS ARE IN SURPRISINGLY GOOD
AGREEMENT THROUGH WEDNESDAY...AFTER WHICH THEY DIVERGE WITH REGARD
TO HOW FAR OFFSHORE THE COLD FRONT PROGRESSES. MODEL PWATS HOVER
AROUND 2.2 INCHES TUESDAY INTO WEDNESDAY...WHICH COUPLED WITH A
SURFACE BOUNDARY AND MODERATE SURFACE HEATING WILL RESULT IN GOOD
COVERAGE OF SHOWERS/STORMS. HEAVY RAINFALL WILL DEFINITELY BE A
CONCERN GIVEN SUCH A MOIST ENVIRONMENT AND THE SLOW-MOVING FRONT. WE
BUMPED POPS UP TO AROUND 50 PERCENT.
THURSDAY INTO FRIDAY THE GFS HANGS THE FRONT ALONG THE COAST WHILE
THE ECMWF PUSHES IT FARTHER OFFSHORE WITH DRY HIGH PRESSURE BUILDING
FROM THE WEST. WE TOOK A COMPROMISE SOLUTION AND TONED DOWN POPS
DURING THE PERIOD BUT MAINTAINED AT LEAST ISOLATED COVERAGE.
EXCEPT FOR A WARMER DAY ON TUESDAY...THE REMAINDER OF THE PERIOD
WILL FEATURE HIGH TEMPS CLOSE TO 90.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
VFR THIS MORNING. THEN...GUIDANCE POINTS TOWARD AN ACTIVE DAY FOR
SHOWERS/THUNDERSTORMS BEGINNING 15-18Z AND CONTINUING INTO THIS
EVENING. SOME THUNDERSTORMS WILL PRODUCE GUSTY WINDS AND BRIEF IFR
OR LOWER CONDITIONS IN HEAVY RAIN. 12Z TAFS WILL MAINTAIN ONGOING
VCTS ACCOMPANIED BY A 4 HOUR TEMPO PERIOD FOR DIRECT THUNDERSTORM
IMPACTS. HOWEVER...PRECISE TIMING/MAGNITUDE OF IMPACTS REMAIN
ELUSIVE...SO EXPECT AMENDMENTS AS DICTATED BY NEAR TERM CONVECTIVE
TRENDS THROUGH THE 12Z TAF PERIOD.
FLIGHT RESTRICTIONS COULD DEVELOP OVERNIGHT IF HEAVY RAIN OCCURS...
BUT FORECAST CONFIDENCE REMAINS TOO LOW TO WARRANT A MENTION
WITHIN 12Z TAFS.
EXTENDED AVIATION OUTLOOK...MAINLY VFR. BRIEF FLIGHT RESTRICTIONS
POSSIBLE DUE MAINLY TO AFTERNOON SHOWERS/THUNDERSTORMS WITH THE
GREATEST COVERAGE TUESDAY INTO WEDNESDAY.
&&
.MARINE...
A WEAK PRESSURE PATTERN AND THE PRESENCE OF BOUNDARIES...INCLUDING
THE LAND BREEZE BOUNDARY OVER COASTAL WATERS THIS MORNING...AND
OTHER FACTORS INCLUDING WATER TEMPS IN THE 80S...DEEP MOISTURE AND
LOW LCLS WILL SUPPORT THE POTENTIAL FOR ISOLATED WATERSPOUTS TODAY.
THE WEAK PRESSURE PATTERN WILL PREVAIL TODAY AND TONIGHT. AN EARLY
MORNING LAND BREEZE/OFFSHORE WINDS MAINLY 10 KT OR LESS WILL GIVE
WAY TO THE SEA BREEZE CIRCULATION/ONSHORE WINDS MAINLY 15 KT OR LESS
BY AFTERNOON. HOWEVER...EXPECTED THUNDERSTORMS/ASSOCIATED OUTFLOW
WILL GREATLY ALTER LOCAL WINDS THROUGH THE PERIOD. THUS...LOCAL
WINDS WILL OCCASIONALLY VARY SIGNIFICANTLY FROM DETERMINISTIC WIND
DIRECTION/SPEED FORECASTS PRESENTED WITHIN THE LATEST FORECAST
PACKAGE. SEAS WILL REMAIN IN THE 2-3 FT RANGE...PERHAPS AS HIGH AS
4 FT BEYOND 20 NM ESPECIALLY THIS MORNING.
SOUTHEAST FLOW ON SATURDAY BECOMES MORE SOUTHERLY SUNDAY INTO MONDAY
AS ATLANTIC HIGH PRESSURE GRADUALLY STRENGTHENS. THROUGH THE WEEKEND
THE AFTERNOON SEA BREEZE ALONG THE COAST AND WEAK NOCTURNAL SURGING
WILL BE THE MAIN FEATURES. MONDAY NIGHT THROUGH THURSDAY WE EXPECT
INCREASING SOUTH TO SOUTHWESTERLY FLOW AHEAD OF A SLOWLY ADVANCING
COLD FRONT. SUSTAINED WINDS OF 15-20 KT OVER THE COASTAL WATERS WITH
SEAS BUILDING AS HIGH AS 5 FT EXPECTED. THIS SHOULD REMAIN JUST
BELOW ADVISORY THRESHOLDS ALTHOUGH A SHORT-DURATION SMALL CRAFT
CANNOT BE COMPLETELY RULED OUT. WINDS IN CHARLESTON HARBOR WILL BE
GUSTY DURING THIS PERIOD DUE TO THE ENHANCED GRADIENT...AND A SMALL
CRAFT ADVISORY FOR A BEEFY AFTERNOON SEA BREEZE TUESDAY OR WEDNESDAY
IS NOT OUT OF THE QUESTION.
&&
.TIDES/COASTAL FLOODING...
ELEVATED TIDES COULD BRIEFLY EXCEED COASTAL FLOOD ADVISORY LEVELS
AROUND 8 PM THIS EVENING...BUT AS OF EARLY FRIDAY MORNING
DEPARTURES REMAIN SMALL. THUS...DO NOT PLAN TO ISSUE ANY
ADVISORIES THIS MORNING.
ASTRONOMICAL HIGH TIDES DUE TO THE FULL MOON/PERIGEE AND LIGHT TO
MODERATE ONSHORE WINDS COULD RESULT IN MINOR COASTAL FLOODING NEAR
THE TIMES OF HIGH TIDE DURING THE EVENING HOURS SATURDAY THROUGH EARLY
NEXT WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...SPR
SHORT TERM...JRL/SPR
LONG TERM...JRL
AVIATION...JRL/SPR
MARINE...JRL/SPR
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
900 AM CDT FRI JUL 11 2014
.DISCUSSION...
259 AM CDT
TODAY...
LARGEST FOCUS FOR THE DAY WILL BE ON THE GRADUAL DEPARTURE TO THE
SFC RIDGE...WHICH GUIDANCE HAS SLOWED SLIGHTLY. THIS SHUD ALLOW FOR
A MOSTLY DRY DAY...HOWEVER AS THE EVENING PROGRESSES AND HIGHER DEW
PTS STEADILY ADVECT NORTH ACROSS THE FORECAST AREA...PRECIP CHANCES
WILL STEADILY INCREASE. AT THIS TIME CONFIDENCE IS HIGH THAT ANY
PRECIP WILL NOW HOLD OFF UNTIL AFT 00Z...SO HAVE PUSHED THE TIMING
BACK A FEW HOURS. THE THERMAL TROUGH THAT HELPED TO KEEP TEMPS DOWN
A FEW DEGREES WILL ALSO DEPART TODAY...HOWEVER CLOUDS WILL BE
STEADILY ON THE INCREASE THROUGHOUT THE AFTERNOON. BUT EXPECT TEMPS
REBOUNDING INTO THE UPR 70S TO LOW 80S. WINDS SHUD BE GENERALLY
SOUTHERLY...THE ONLY EXCEPTION COULD BE FAR NORTHEAST IL WHERE WINDS
MAY BE SLIGHTLY TURNED FROM THE SOUTHEAST AND USHER IN SLIGHTLY
COOLER AIR INTO NORTHEAST LAKE COUNTY.
TONIGHT THROUGH SATURDAY...
AS PREVIOUSLY NOTED...HAVE PUSHED BACK THE TIMING OF THE PRECIP
UNTIL AFT 00Z. SOME WEAK DIFFLUENCE IN THE MID-LVLS IS STILL
PRESENT...ALTHOUGH STEADILY WEAKENING AS THE EVENING PROGRESSES.
WARM/MOIST AIR WILL CONTINUE TO ADVECT NORTH INTO THE FORECAST
AREA...WITH SKIES BECOMING MOSTLY CLOUDY. INSTABILITY AT THE ONSET
IS NOT SIGNIFICANT...SO EXPECT THE LEADING EDGE OF THE PRECIP TO
PERHAPS NOT HAVE MUCH CONVECTION WITH IT. THIS WILL HOWEVER CHANGE
AS THE OVERNIGHT HOURS PROGRESS INTO SAT MORNING. HI-RES LCL ARW8KM
HAS FOR A FEW CYCLES BEEN SUGGESTIVE OF A LOBE OF VORTICITY SLIDING
EAST/SOUTHEAST ACROSS IA/CENTRAL IL AFT 09Z SAT THEN TURNING
SOUTHEAST. PWAT VALUES CONTINUE TO BE PROGGED AT 3 TO 4 SIGMA...OR
HOVERING AT 2" FOR MUCH OF THE FORECAST AREA. SO ANY CONVECTION THAT
DEVELOPS COULD EASILY PRODUCE SOME BRIEF HEAVY DOWNPOURS.
SAT MORNING MAY FEATURE A BRIEF LULL IN THE ACTIVITY...DESPITE THE
HIGH DEW PTS THAT WILL CONTINUE TO ADVECT NORTH/NORTHEAST ACROSS THE
REGION. A FEW SOLUTIONS HAVE CONTINUED TO POINT TOWARDS DEW PTS
NEARING THE MID 70S BY SAT AFTN. SO A VERY HUMID ENVIRONMENT IS IN
SHAPE FOR SAT...FORTUNATELY ABUNDANT CLOUD COVER WILL KEEP TEMPS
FROM GETTING TOO OUT OF CONTROL. THUS HAVE ONLY MADE MINOR
ADJUSTMENTS TO THE AFTN HIGHS...WHICH WILL GENERALLY BE IN THE
LOW/MID 80S.
THE FOCUS FOR ADDTL CONVECTIVE DEVELOPMENT WILL BE ON THE SHORTWAVE
PROGGED TO BE LIFTING INTO THE CENTRAL PLAINS SAT AFTN. THE MAIN
TROUGH AXIS WILL BE STARTING TO DIG INTO THE NORTHERN PLAINS SAT
AFTN/EVE...WHICH WILL AID IN INCREASING THE SOUTHWEST LLVL FLOW SAT
EVE FOR THE FORECAST AREA. THIS COUPLED WITH INCREASING
SHEAR...COULD AID IN THE POTENTIAL FOR STRONG TO PERHAPS SEVERE
STORMS TO DEVELOP SAT EVE. GENERAL STORM MOTION SHOULD BE WEST-EAST.
CONFIDENCE...MEDIUM/HIGH.
SUNDAY THROUGH THURSDAY...
FOCUS FOR THE SECOND HALF OF THE WEEKEND INTO NEXT WEEK WILL BE THE
UNSEASONABLY COOL WEATHER EXPECTED FOR NEXT WEEK. ALTHOUGH PRIOR TO
THE ARRIVAL...SUN WILL FEATURE A COUPLE BOUNDARIES PUSHING EAST
ACROSS THE REGION. A WEAK BOUNDARY SHUD BE ORIENTED FROM NORTHERN MO
STRETCHING NORTHEAST THRU SOUTHERN MI...WITH A SECONDARY WAVE
APPROACHING THE REGION LATE SUN NGT/EARLY MON. THE 500MB VORT WILL
BE ARRIVING OVER THE UPPER MIDWEST LATE SUN...WITH A FEW WEAK LOBES
OF VORTICITY PIVOTING ARND THE AXIS. 850MB THERMAL TROUGH WILL ONLY
CONTINUE TO COOL AS TIME PROGRESSES...AND EXPECT BY TUE TEMPS ALOFT
TO NEAR -3 SIGMA. ENSEMBLES HAVE MAINTAINED A HIGH CONFIDENCE WITH
MINIMAL SPREAD FOR NUMEROUS CYCLES. BASED ON THE PATTERN OF A HIGH
AMPLITUDE RIDGE DEVELOPING ACROSS THE WESTERN CONUS/CANADA...THIS
WILL TRANSLATE INTO A DEEP/STRONG TROUGH FOR THE GREAT LAKES. EXPECT
TEMPS TUE TO STRUGGLE TO WARM BEYOND THE UPR 60S FOR SOME LOCATIONS
NORTH OF I-80...AND PERHAPS ARND 70 ELSEWHERE.
AS THE EXTENDED PERIODS PROGRESS...THE POTENCY OF THE TROUGH BEGINS
TO MODERATE AND TEMPS START TO WARM GENERALLY INTO THE MID 70S WITH
BROAD SFC RIDGING BUILDING IN.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* POTENTIAL FOR A LAKE BREEZE THIS AFTERNOON.
* TSRA LATER TONIGHT WITH MVFR/IFR POSSIBLE.
* MVFR CONDITIONS AFTER TSRA NEAR DAYBREAK SATURDAY.
MDB
//DISCUSSION...UPDATED 14Z...
NOT MUCH CHANGE IN FORECAST THINKING WITH REGARD TO WINDS FOR
TODAY.
MDB
FROM 12Z...
BENIGN CONDITIONS THIS MORNING ACROSS THE TERMINALS AS HIGH
PRESSURE SHIFTS EAST OF THE AREA RESULTING IN LIGHT SSE WINDS.
WINDS WILL GRADUALLY PICK UP OUT OF THE SOUTH FROM WEST TO EAST AS
THE GRADIENT INCREASES. LAKE BREEZE IS THE FIRST CHALLENGE IN THIS
TAF PACKAGE. CONCERN IS THAT THE GRADIENT WILL NOT BE STRONG
ENOUGH TO PREVENT THE LAKE BREEZE FROM MAKING IT TO MDW AND
POSSIBLY ORD. THERE IS MIXED SIGNALS IN HIGH RESOLUTION
GUIDANCE...AS THE HRRR BRINGS THE LAKE BREEZE THROUGH BOTH ORD AND
MDW...WHILE MOST OTHER GUIDANCE BRINGS IT CLOSE BEFORE LOWER LEVEL
SOUTHERLY WINDS PICK UP. WILL CONTINUE WITH CURRENT THINKING THAT
IT WILL GET TO MDW AND NOT QUITE TO ORD BUT CONFIDENCE ON THIS IS
NOT SUPER HIGH.
ONCE SOUTHERLY WINDS PICK UP AND LIMIT THE LAKE BREEZE...CONCERN
SHIFTS TO THUNDERSTORM ACTIVITY LATER TONIGHT. HAVE GONE WITH
PROB30 TSRA AS CONFIDENCE IS NOT HIGH ON THE TIMING AT THIS POINT
AND IT COULD ACTUALLY BE A LITTLE SOONER THAN IN THE CURRENT
FORECAST. IT LOOKS LIKE SHOWERS WITH EMBEDDED THUNDER AS
INSTABILITY IS NOT ALL THAT HIGH. AFTER THUNDERSTORM ACTIVITY
CLEARS...EXPECT LINGERING LOW LEVEL MOISTURE AND A LIGHT GRADIENT
WILL RESULT IN MVFR CIGS FOR A TIME.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* LOW CONFIDENCE IN LAKE BREEZE REACHING ORD TODAY...LOW TO
MEDIUM CONFIDENCE IN GETTING VERY CLOSE TO MDW.
* MEDIUM CONFIDENCE IN TSRA IMPACTING THE TERMINALS LATE
TONIGHT...BUT LOW CONFIDENCE ON TIMING.
* MEDIUM CONFIDENCE ON MVFR CIGS FOLLOWING TSRA...BUT LOW
CONFIDENCE ON TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...TSRA WITH MVFR/IFR POSSIBLE.
SUNDAY THROUGH TUESDAY...PERIODIC CHANCES FOR TSRA/SHRA. PRIMARILY VFR.
WEDNESDAY THROUGH THURSDAY...SMALL CHANCES FOR SHRA. PRIMARILY VFR.
KMD
&&
.MARINE...
332 AM CDT
HIGH PRESSURE HAS SHIFTED TO THE EASTERN GREAT LAKES EARLY THIS
MORNING...AND WINDS HAVE TURNED MORE SOUTHERLY ACROSS THE LAKE.
EXPECT SPEEDS TO INCREASE TODAY IN RESPONSE TO A STRONGER GRADIENT
CREATED BY LOW PRESSURE CENTERED IN NORTHERN MANITOBA AND INTO THE
NORTHERN PLAINS. THE STRONGER GRADIENT WILL BE OVER THE NORTHERN
HALF OF THE LAKE...WHERE SOUTH WINDS INCREASE TO 15 TO 25 KT...WHILE
THE SOUTH HALF WILL SEE S TO SE WINDS AT 10-20 KT. WINDS DIMINISH
SATURDAY AS A TROUGH OF LOW PRESSURE MOVES OVERHEAD AND BECOME
SOUTHWEST SATURDAY NIGHT.
A LOW PASSES WELL NORTH OF THE LAKE SATURDAY NIGHT AND SUNDAY AND
ITS COLD FRONT SWINGS OVER THE LAKE SUNDAY MORNING. WINDS BECOME
WEST BEHIND THE FRONT MAINLY FOR THE NORTHERN HALF...AND THEN A
SECOND FRONT PUSHES DOWN THE LAKE SUNDAY NIGHT INTO MONDAY BEFORE
FINALLY CLEARING THE LAKE MONDAY EVENING. WINDS WILL BECOME NORTH
TO NORTHWEST 10-20 KT BEHIND THE FRONT. WINDS DIMINISH LATE TUESDAY
NIGHT AND THEN HIGH PRESSURE MOVES OVER THE LAKE WEDNESDAY NIGHT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
644 AM CDT FRI JUL 11 2014
.DISCUSSION...
259 AM CDT
TODAY...
LARGEST FOCUS FOR THE DAY WILL BE ON THE GRADUAL DEPARTURE TO THE
SFC RIDGE...WHICH GUIDANCE HAS SLOWED SLIGHTLY. THIS SHUD ALLOW FOR
A MOSTLY DRY DAY...HOWEVER AS THE EVENING PROGRESSES AND HIGHER DEW
PTS STEADILY ADVECT NORTH ACROSS THE FORECAST AREA...PRECIP CHANCES
WILL STEADILY INCREASE. AT THIS TIME CONFIDENCE IS HIGH THAT ANY
PRECIP WILL NOW HOLD OFF UNTIL AFT 00Z...SO HAVE PUSHED THE TIMING
BACK A FEW HOURS. THE THERMAL TROUGH THAT HELPED TO KEEP TEMPS DOWN
A FEW DEGREES WILL ALSO DEPART TODAY...HOWEVER CLOUDS WILL BE
STEADILY ON THE INCREASE THROUGHOUT THE AFTERNOON. BUT EXPECT TEMPS
REBOUNDING INTO THE UPR 70S TO LOW 80S. WINDS SHUD BE GENERALLY
SOUTHERLY...THE ONLY EXCEPTION COULD BE FAR NORTHEAST IL WHERE WINDS
MAY BE SLIGHTLY TURNED FROM THE SOUTHEAST AND USHER IN SLIGHTLY
COOLER AIR INTO NORTHEAST LAKE COUNTY.
TONIGHT THROUGH SATURDAY...
AS PREVIOUSLY NOTED...HAVE PUSHED BACK THE TIMING OF THE PRECIP
UNTIL AFT 00Z. SOME WEAK DIFFLUENCE IN THE MID-LVLS IS STILL
PRESENT...ALTHOUGH STEADILY WEAKENING AS THE EVENING PROGRESSES.
WARM/MOIST AIR WILL CONTINUE TO ADVECT NORTH INTO THE FORECAST
AREA...WITH SKIES BECOMING MOSTLY CLOUDY. INSTABILITY AT THE ONSET
IS NOT SIGNIFICANT...SO EXPECT THE LEADING EDGE OF THE PRECIP TO
PERHAPS NOT HAVE MUCH CONVECTION WITH IT. THIS WILL HOWEVER CHANGE
AS THE OVERNIGHT HOURS PROGRESS INTO SAT MORNING. HI-RES LCL ARW8KM
HAS FOR A FEW CYCLES BEEN SUGGESTIVE OF A LOBE OF VORTICITY SLIDING
EAST/SOUTHEAST ACROSS IA/CENTRAL IL AFT 09Z SAT THEN TURNING
SOUTHEAST. PWAT VALUES CONTINUE TO BE PROGGED AT 3 TO 4 SIGMA...OR
HOVERING AT 2" FOR MUCH OF THE FORECAST AREA. SO ANY CONVECTION THAT
DEVELOPS COULD EASILY PRODUCE SOME BRIEF HEAVY DOWNPOURS.
SAT MORNING MAY FEATURE A BRIEF LULL IN THE ACTIVITY...DESPITE THE
HIGH DEW PTS THAT WILL CONTINUE TO ADVECT NORTH/NORTHEAST ACROSS THE
REGION. A FEW SOLUTIONS HAVE CONTINUED TO POINT TOWARDS DEW PTS
NEARING THE MID 70S BY SAT AFTN. SO A VERY HUMID ENVIRONMENT IS IN
SHAPE FOR SAT...FORTUNATELY ABUNDANT CLOUD COVER WILL KEEP TEMPS
FROM GETTING TOO OUT OF CONTROL. THUS HAVE ONLY MADE MINOR
ADJUSTMENTS TO THE AFTN HIGHS...WHICH WILL GENERALLY BE IN THE
LOW/MID 80S.
THE FOCUS FOR ADDTL CONVECTIVE DEVELOPMENT WILL BE ON THE SHORTWAVE
PROGGED TO BE LIFTING INTO THE CENTRAL PLAINS SAT AFTN. THE MAIN
TROUGH AXIS WILL BE STARTING TO DIG INTO THE NORTHERN PLAINS SAT
AFTN/EVE...WHICH WILL AID IN INCREASING THE SOUTHWEST LLVL FLOW SAT
EVE FOR THE FORECAST AREA. THIS COUPLED WITH INCREASING
SHEAR...COULD AID IN THE POTENTIAL FOR STRONG TO PERHAPS SEVERE
STORMS TO DEVELOP SAT EVE. GENERAL STORM MOTION SHOULD BE WEST-EAST.
CONFIDENCE...MEDIUM/HIGH.
SUNDAY THROUGH THURSDAY...
FOCUS FOR THE SECOND HALF OF THE WEEKEND INTO NEXT WEEK WILL BE THE
UNSEASONABLY COOL WEATHER EXPECTED FOR NEXT WEEK. ALTHOUGH PRIOR TO
THE ARRIVAL...SUN WILL FEATURE A COUPLE BOUNDARIES PUSHING EAST
ACROSS THE REGION. A WEAK BOUNDARY SHUD BE ORIENTED FROM NORTHERN MO
STRETCHING NORTHEAST THRU SOUTHERN MI...WITH A SECONDARY WAVE
APPROACHING THE REGION LATE SUN NGT/EARLY MON. THE 500MB VORT WILL
BE ARRIVING OVER THE UPPER MIDWEST LATE SUN...WITH A FEW WEAK LOBES
OF VORTICITY PIVOTING ARND THE AXIS. 850MB THERMAL TROUGH WILL ONLY
CONTINUE TO COOL AS TIME PROGRESSES...AND EXPECT BY TUE TEMPS ALOFT
TO NEAR -3 SIGMA. ENSEMBLES HAVE MAINTAINED A HIGH CONFIDENCE WITH
MINIMAL SPREAD FOR NUMEROUS CYCLES. BASED ON THE PATTERN OF A HIGH
AMPLITUDE RIDGE DEVELOPING ACROSS THE WESTERN CONUS/CANADA...THIS
WILL TRANSLATE INTO A DEEP/STRONG TROUGH FOR THE GREAT LAKES. EXPECT
TEMPS TUE TO STRUGGLE TO WARM BEYOND THE UPR 60S FOR SOME LOCATIONS
NORTH OF I-80...AND PERHAPS ARND 70 ELSEWHERE.
AS THE EXTENDED PERIODS PROGRESS...THE POTENCY OF THE TROUGH BEGINS
TO MODERATE AND TEMPS START TO WARM GENERALLY INTO THE MID 70S WITH
BROAD SFC RIDGING BUILDING IN.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* POTENTIAL FOR A LAKE BREEZE THIS AFTERNOON
* TSRA LATER TONIGHT WITH MVFR/IFR POSSIBLE
* MVFR CONDITIONS AFTER TSRA NEAR DAYBREAK SATURDAY
KMD
//DISCUSSION...UPDATED 12Z...
BENIGN CONDITIONS THIS MORNING ACROSS THE TERMINALS AS HIGH
PRESSURE SHIFTS EAST OF THE AREA RESULTING IN LIGHT SSE WINDS.
WINDS WILL GRADUALLY PICK UP OUT OF THE SOUTH FROM WEST TO EAST AS
THE GRADIENT INCREASES. LAKE BREEZE IS THE FIRST CHALLENGE IN THIS
TAF PACKAGE. CONCERN IS THAT THE GRADIENT WILL NOT BE STRONG
ENOUGH TO PREVENT THE LAKE BREEZE FROM MAKING IT TO MDW AND
POSSIBLY ORD. THERE IS MIXED SIGNALS IN HIGH RESOLUTION
GUIDANCE...AS THE HRRR BRINGS THE LAKE BREEZE THROUGH BOTH ORD AND
MDW...WHILE MOST OTHER GUIDANCE BRINGS IT CLOSE BEFORE LOWER LEVEL
SOUTHERLY WINDS PICK UP. WILL CONTINUE WITH CURRENT THINKING THAT
IT WILL GET TO MDW AND NOT QUITE TO ORD BUT CONFIDENCE ON THIS IS
NOT SUPER HIGH.
ONCE SOUTHERLY WINDS PICK UP AND LIMIT THE LAKE BREEZE...CONCERN
SHIFTS TO THUNDERSTORM ACTIVITY LATER TONIGHT. HAVE GONE WITH
PROB30 TSRA AS CONFIDENCE IS NOT HIGH ON THE TIMING AT THIS POINT
AND IT COULD ACTUALLY BE A LITTLE SOONER THAN IN THE CURRENT
FORECAST. IT LOOKS LIKE SHOWERS WITH EMBEDDED THUNDER AS
INSTABILITY IS NOT ALL THAT HIGH. AFTER THUNDERSTORM ACTIVITY
CLEARS...EXPECT LINGERING LOW LEVEL MOISTURE AND A LIGHT GRADIENT
WILL RESULT IN MVFR CIGS FOR A TIME.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* LOW CONFIDENCE IN LAKE BREEZE REACHING ORD FRIDAY...LOW TO
MEDIUM CONFIDENCE IN GETTING VERY CLOSE TO MDW
* MEDIUM CONFIDENCE IN TSRA IMPACTING THE TERMINALS LATE
TONIGHT...BUT LOW CONFIDENCE ON TIMING
* MEDIUM CONFIDENCE ON MVFR CIGS FOLLOWING TSRA...BUT LOW
CONFIDENCE ON TIMING
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...TSRA WITH MVFR/IFR POSSIBLE.
SUNDAY THROUGH TUESDAY...PERIODIC CHANCES FOR TSRA/SHRA. PRIMARILY VFR.
WEDNESDAY THROUGH THURSDAY...SMALL CHANCES FOR SHRA. PRIMARILY VFR.
KMD
&&
.MARINE...
332 AM CDT
HIGH PRESSURE HAS SHIFTED TO THE EASTERN GREAT LAKES EARLY THIS
MORNING...AND WINDS HAVE TURNED MORE SOUTHERLY ACROSS THE LAKE.
EXPECT SPEEDS TO INCREASE TODAY IN RESPONSE TO A STRONGER GRADIENT
CREATED BY LOW PRESSURE CENTERED IN NORTHERN MANITOBA AND INTO THE
NORTHERN PLAINS. THE STRONGER GRADIENT WILL BE OVER THE NORTHERN
HALF OF THE LAKE...WHERE SOUTH WINDS INCREASE TO 15 TO 25 KT...WHILE
THE SOUTH HALF WILL SEE S TO SE WINDS AT 10-20 KT. WINDS DIMINISH
SATURDAY AS A TROUGH OF LOW PRESSURE MOVES OVERHEAD AND BECOME
SOUTHWEST SATURDAY NIGHT.
A LOW PASSES WELL NORTH OF THE LAKE SATURDAY NIGHT AND SUNDAY AND
ITS COLD FRONT SWINGS OVER THE LAKE SUNDAY MORNING. WINDS BECOME
WEST BEHIND THE FRONT MAINLY FOR THE NORTHERN HALF...AND THEN A
SECOND FRONT PUSHES DOWN THE LAKE SUNDAY NIGHT INTO MONDAY BEFORE
FINALLY CLEARING THE LAKE MONDAY EVENING. WINDS WILL BECOME NORTH
TO NORTHWEST 10-20 KT BEHIND THE FRONT. WINDS DIMINISH LATE TUESDAY
NIGHT AND THEN HIGH PRESSURE MOVES OVER THE LAKE WEDNESDAY NIGHT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1039 AM CDT FRI JUL 11 2014
.UPDATE...
VISIBLE SATELLITE IMAGERY SHOWING CLOUDS BOILING UP ALONG THE
COASTLINE PRETTY MUCH OUTLINING THE SEA BREEZE RIGHT ALONG THE
COAST. CLOUD BUILDUP INITIALLY LOOKED BETTER NEAR SABINE LAKE
AREA...THEN POOF...GONE...TO STABLE THERE STILL. THERE IS ALSO
BUILDUP FROM EAST OF GRAND CHENIER EXTENDING EAST TO PECAN
ISLAND. RADAR ALSO SHOWING THE INITIAL BUDDINGS OF SHOWERS
DEVELOPING EAST OF PECAN ISLAND. ONE THING TO NOTE TODAY...THE UPPER
LEVEL STEERING CURRENTS LOOK VERY WEAK. THEREFORE...EXPECT
CONVECTION TO HOLD PRETTY TIGHT TO THE SEA BREEZE. OUTFLOW
BOUNDARIES WILL NEED TO BE EXCEPTIONAL TODAY TO GET BETTER
DISTRIBUTION. MY INITIAL THOUGHTS...ZONE FORECAST PACKAGE LOOKS
PRETTY GOOD. I WILL NOT MAKE ANY CHANGES TO THE CURRENT PACKAGE. I
DO SEE THAT THIS EVENING... HIGH RESOLUTION RAPID REFRESH MODEL
(HRRR) AND WEATHER RESEARCH AND FORECAST MODEL (WRF) ARE SHOWING
SOME CARRYOVER INTO THE EVENING PACKAGE FOR SOME RAIN TO CONTINUE
IN SOME AREAS MOSTLY BETWEEN THE I-10 CORRIDOR BETWEEN LAKE
CHARLES AND LAFAYETTE. WILL MONITOR AND MAKE CHANGES LATER TO
EVENING ZONES IF THIS TREND CONTINUES IN THE HRRR AND WRF MODELS.
DID I SAY IT WAS GOING TO BE HOT AND HUMID TODAY? WELL...DRINK
PLENTY OF FLUID IF YOUR GOING TO BE OUTSIDE. YOU ARE GOING TO NEED
GOOD RE-HYDRATION IF OUT TODAY. :)
&&
.PREV DISCUSSION... /ISSUED 508 AM CDT FRI JUL 11 2014/
AVIATION...
WEAK HIGH PRESSURE ACROSS CENTRAL LOUISIANA WILL PERMIT THE RETURN
OF THE SEA BREEZE ACROSS THE FORECAST AREA. PERSISTENCE BRINGS
THE SEA BREEZE ONSHORE BY MID-MORNING...BEFORE REACHING THE LAKES
REGION AND PINEY HILLS REGION BY LATE AFTERNOON.
LIFT ATTENDING UPPER LEVEL DIVERGENCE (AN ANTICYCLONIC SHEAR ZONE
ALOFT) WILL GIVE AN ADDED BOOST TO THE FRONTAL LIFT ATTENDING THE
SEA BREEZE.
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED...TAPERING OFF WITH
PASSAGE OF SEA BREEZE.
JT
PREV DISCUSSION... /ISSUED 352 AM CDT FRI JUL 11 2014/
DISCUSSION...RADAR CURRENTLY SHOWING JUST A FEW SHOWERS AND
THUNDERSTORMS OVER THE NEAR COASTAL WATERS. SATELLITE DEPICTING
CLEAR SKIES INLAND. OBS BEGINNING TO PICK UP ON SOME LIGHT FOG
DEVELOPMENT HERE AND THERE WHICH HAS BEEN THE CASE THE LAST SEVERAL
NIGHTS.
TODAY AND THE WEEKEND...WITH A WEAKNESS REMAINING ALOFT...AND LOW
LEVEL SOUTHERLIES MAINTAINING ADEQUATE MOISTURE OVER THE FORECAST AREA...
WILL CONTINUE TO SEE DAILY SHOWER AND THUNDERSTORM DEVELOPMENT.
TRIGGER FOR THIS DEVELOPMENT WILL COME FROM A WEAK SEA BREEZE AND
ACCOMPANYING CONVERGENCE SLOWLY ADVANCING NORTHWARD....AS WELL AS
CONVECTIVE OUTFLOWS. OTHERWISE EXPECT A CONTINUATION OF NEAR NORMAL
TEMPERATURES...GENERALLY SPELLING SOMEWHAT HOT AND HUMID
DAYS...AND WARM AND MUGGY NIGHTS.
REMAINDER OF FORECAST...INTENSE CYCLONE PROGGED SIMILARLY BY
MODELS TO DROP OUT OF MID-CANADA AND INTO GREAT LAKES REGION EARLY
IN THE NEW-WEEK. THIS UNLIKELY MID-JULY FEATURE WILL BE
RESPONSIBLE FOR ADVANCING A COOL FRONT INTO THE AREA
TUESDAY...POSSIBLY PUNCHING FEATURE AS FAR SOUTH AS THE NORTHERN GULF
WATERS BEFORE WASHING OUT. SCENARIO PROMPTED AN INCREASE IN POPS
FOR TUESDAY AND TUESDAY NIGHT. SOUTHERN PORTION OF COLD DOME
GLANCING THE AREA WILL BRING NO MORE THAN A SLIGHT DECREASE IN
TEMPS AND DEWPOINTS. MUCH MORE IMPRESSIVE LOWERING OF THESE
ELEMENTS WILL OCCUR FURTHER NORTH AND LIKELY WILL BE RECORD-
BREAKING. RAIN CHANCES THEN CONTINUE THROUGH THE REST OF THE
FORECAST AS STRONG SOUTHERLIES DEVELOP AND IMPULSES APPROACH
AND MOVE OVERHEAD WITHIN A RELATIVELY STRONG JULY NORTHWEST FLOW
ALOFT.
MARINE...WEAK HIGH PRESSURE WILL CONTINUE TO HOLD OVER THE GULF
WATERS MAINTAINING LIGHT WINDS AND LOWS SEAS. ISOLATED SHOWER AND
THUNDERSTORM ACTIVITY WILL GENERALLY BE THROUGH THE NIGHT-TIME
HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 93 76 93 77 / 30 10 30 10
KBPT 92 76 92 76 / 30 20 30 10
KAEX 94 75 93 75 / 20 10 20 10
KLFT 93 76 93 76 / 30 20 30 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE...06
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1015 AM CDT FRI JUL 11 2014
.UPDATE...
MORNING SURFACE ANALYSIS INDICATES FRONTAL BOUNDARY STALLED IN THE
AREA WITH DRIER AIR MOVING INTO NRN MS PER WATER VAPOR IMAGERY.
PWATS HAVE DECREASED NEAR 1.0 INCHES IN 12Z BMX SOUNDING WHILE 12Z
KJAN AND OTHER REGIONAL SOUNDINGS ALONG/W ARE CLOSER TO 1.6-2.0
INCHES. RUC/GFS/EURO INDICATES SOME OF THIS DRIER AIR WILL FILTER
INTO THE E/NE LATER TODAY. ANOTHER S/WV DISTURBANCE WILL MOVE INTO
THE WRN AREAS TODAY AS THE H5 UPPER RIDGE OVER THE CENTRAL PLAINS
MOVES TO THE SE TODAY. FLOW ALOFT HAS BECOME MORE FROM THE NW/N AND
WILL CONTINUE TO BECOME MORE FROM THE N THROUGH THE AFTERNOON. AS
SOME OF THE DRIER AIR FILTERS IN THE E/NE AND THE S/WV MOVES
IN...EXPECT THE BEST POPS TO REMAIN ALONG/W OF THE I-55 CORRIDOR
WITH DECREASING POPS IN THE E/NE. ADJUSTED POPS TO REFLECT HIGHEST
IN THE W MAINLY AFTER 17Z. LOCAL WET MICROBURST CHECKLIST REVEALS A
RISK DUE TO GOOD VERTICAL TOTALS APPROACHING 27-28 DEG C AND SBCAPES
AROUND 3000 J/KG. EXPECTING THE ACTIVITY TO REMAIN ISOLATED TO
POSSIBLY SCATTERED IN THE W BUT NOT WIDESPREAD ENOUGH TO MENTION IN
THE HWO. A STRONG TO SEVERE STORM CAN NOT BE RULED OUT BUT WOULD
REMAIN ISOLATED AT MOST. LOCALLY HEAVY RAIN IS ALSO POSSIBLE DUE TO
DEEP MOISTURE AND SLOW STORM MOVEMENT. HIGHS TODAY LOOK ON TRACK IN
THE LOWER 90S DUE TO STORMS/CLOUDS IN THE REGION. A HOT AND HUMID
AFTERNOON IS IN STORE WITH HEAT INDICES IN THE UPPER 90S TO NEAR 100
DEGREES IN W/SW. ADJUSTED HOURLY TEMPS/DEWPOINTS/SKY GRIDS TO CURRENT
TRENDS. REST OF THE FORECAST IS ON TRACK. /DC/
&&
.AVIATION...CONVECTION ALREADY DEVELOPING THIS MORNING OVER NW MS
WILL CONTINUE TO DROP S AND INCREASE IN COVERAGE THROUGH THE
AFTERNOON AS ADVERTISED BY THE HRRR MODEL. WILL CONTINUE VICINITY TS
IN W MS TAF SITES WHILE EASTERN AREAS WILL SEE SOMEWHAT LESS
COVERAGE. CONVECTION WILL WIND DOWN DURING THE EARLY EVENING WITH
MVFR VISIBILITIES IN MIST DEVELOPING AFTER 06Z IN THOSE AREAS THAT
GET RAINFALL TODAY. VFR CONDITIONS WILL RETURN BY 14Z DUE TO
INCREASED MIXING. /26/
&&
.PREV DISCUSSION... /ISSUED 355 AM CDT FRI JUL 11 2014/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...A DISTURBANCE THAT
MOVED INTO MY NORTHWEST ZONES YESTERDAY EVENING AND HAS BEEN
RESPONSIBLE FOR SHOWERS AND A FEW STORMS LINGERING OVER THE CWA
OVERNIGHT...CONTINUES ITS TREK TO THE SOUTHEAST OVER THE AREA THIS
MORNING. MEANWHILE LOOKING UPSTREAM...IT APPEARS THAT ANOTHER
DISTURBANCE IS POISED TO MOVE INTO AND THROUGH THE FORECAST AREA
FROM NORTHWEST TO SOUTHEAST YET AGAIN THROUGH THE COURSE OF TODAY.
THIS...A VERY MOIST AIRMASS AS WE REMAIN SOUTH OF A FRONT MEANDERING
ABOUT OVER NORTH MISSISSIPPI (I.E. PRECIPITABLE H2O VALUES AROUND 2
INCHES)...AND DAYTIME HEATING...WILL AGAIN LEAD TO SHOWERS AND
STORMS DEVELOPING PREDOMINATELY DURING THE AFTERNOON HOURS TODAY.
BECAUSE OF THIS MOISTURE RICH AIRMASS...LOCALLY HEAVY RAIN AGAIN
LOOKS TO BE THE BIGGEST CONCERN WITH CONVECTION TODAY...ALTHOUGH
SOME GUSTS AROUND 30 MPH CAN`T BE RULED OUT WITH THE MOST INTENSE
CONVECTION.
BEST RAIN CHANCES TODAY AGAIN APPEAR TO BE OVER AREAS GENERALLY
ALONG AND WEST OF THE HIGHWAY 49 CORRIDOR. WITH SOME SLIGHTLY DRIER
AIR FILTERING IN...PLUS THE OVERALL MID/UPPER FLOW ACROSS THE
AREA...RAIN CHANCES LOOK TO BE LESS OVER EAST CENTRAL AND NORTHEAST
MISSISSIPPI. CONVECTION WILL BEGIN TO WANE AFTER SUNSET THIS
EVENING.
FOR SATURDAY AND SATURDAY NIGHT...A DEEPER PUSH OF SLIGHTLY DRY AIR
INTO THE REGION IS CURRENTLY FORECAST. IN ADDITION TO THIS...AN
INCREASE IN MID/UPPER LEVEL RIDGING WILL ALLOW FOR LESS RAIN CHANCES
OVER THE CWA AS THEY BECOME CONFINED TO MAINLY LOCALES SOUTH OF THE
INTERSTATE 20 CORRIDOR. ONCE AGAIN...CONVECTION WILL BE CONFINED TO
MAINLY THE AFTERNOON HOURS...WITH A GRADUAL DISSIPATION IN ACTIVITY
EXPECTED AFTER SUNSET.
AS FAR AS TEMPERATURES ARE CONCERNED...I STAYED PRETTY CLOSE TO
GUIDANCE IN TERMS OF LOW TEMPERATURES. HOWEVER...BECAUSE OF MOIST
GROUND CONDITIONS AND CLOUDS...ESPECIALLY FOR THIS AFTERNOON...I DID
ADJUST HIGHS TEMPERATURES DOWN A BIT. /19/
LONG TERM...SUNDAY THROUGH FRIDAY...BROAD RIDGING WILL BE IN PLACE
OVER THE REGION AT THE START OF THE LONG TERM. THIS WILL BRING
SLIGHTLY ABOVE NORMAL TEMPERATURES TO THE REGION. GUIDANCE WAS A
LITTLE ROBUST IN HIGHS FOR SUNDAY AND FELT THAT GIVEN ENOUGH GROUND
MOISTURE PRESENT STILL FROM RECENT RAINFALL AND POTENTIAL FOR ADDITIONAL
CONVECTION...GOING SLIGHTLY CLOSER TO THE NAM/ECMWF WOULD BE A
BETTER FIT. WITH HIGHS IN THE 90S...AND PLENTY OF MOISTURE IN
PLACE(PW VALUES AROUND 1.7-1.9 INCHES)...THERE SHOULD BE SOME
AFTERNOON AND EARLY EVENING CONVECTION. ANOTHER CONCERN FOR SUNDAY
WILL BE FROM HEAT STRESS. MUGGY CONDITIONS WILL OCCUR AND THIS COULD
BRING SOME HEAT INDICES...ESPECIALLY IN THE WESTERN PORTIONS OF THE
CWA...TO AROUND 101-103 DEGREES. VALUES SHOULD STILL REMAIN BELOW
CRITERIA FOR ANY ADVISORIES BUT THIS WILL NEED TO BE MONITORED FOR
AT LEAST MAYBE SOME MENTION OF LIMITED POTENTIAL IN THE HWO.
THE MAIN STORY OF THE EXTENDED FORECAST IS IN THE PATTERN CHANGE
THAT WILL BE UNDERWAY AT THE START TO MIDDLE OF THE WORK WEEK. A
LARGE UPPER TROUGH WILL TAKE SHAPE AND SET UP OVER THE GREAT LAKES
REGION. THIS WILL SEND AN UNSEASONABLY STRONG COLD FRONT OUR WAY FOR
TUESDAY INTO WEDNESDAY. SHOWERS AND THUNDERSTORMS WILL OCCUR ALONG
AND AHEAD OF THE FRONT ON TUESDAY BUT AT THIS TIME PARAMETERS DONT
LOOK VERY IMPRESSIVE FOR SEVERE STORMS. AS THE FRONT MOVES
THROUGH...CHANCES FOR RAIN WILL CONTINUE ESPECIALLY IN THE SOUTH
WHERE DRIER AIR WILL BE SLOWER TO MOVE IN. TEMPERATURES THROUGH MID
WEEK WILL BE FAIRLY PLEASANT IN THE 80S FOR MOST ALL LOCATIONS AND
EVEN LOWER 80S IN THE NORTH. OVERNIGHT LOWS WILL BE IN THE 60S.
AS THE UPPER TROUGH REMAINS EXTENDED ACROSS THE SOUTH...SEVERAL WEAK
DISTURBANCES IN THE FLOW WILL MOVE ACROSS OUR AREA THROUGH THE END
OF THE WEEK. THESE WILL COMBINE WITH MOISTURE CHARACTERIZED BY ~1.7
INCH FORECAST PW VALUES...AND KEEP AT LEAST SOME CHANCE FOR RAIN IN
THE FORECAST. TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE END
OF THE WEEK. /28/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 93 70 94 70 / 29 11 5 9
MERIDIAN 92 69 94 69 / 13 9 7 7
VICKSBURG 93 68 93 69 / 37 12 7 10
HATTIESBURG 93 70 95 72 / 24 10 18 13
NATCHEZ 91 70 93 71 / 36 15 22 14
GREENVILLE 92 71 94 71 / 36 10 3 8
GREENWOOD 92 69 93 69 / 26 10 3 7
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/26/19/28
AREA FORECAST DISCUSSION
NWS BISMARCK ND
802 AM CDT FRI JUL 11 2014
.UPDATE...
ISSUED AT 802 AM CDT FRI JUL 11 2014
LATEST SURFACE ANALYSIS PLACES THE COLD FRONT INTO THE JAMES RIVER
VALLEY WITH 3HR PRESSURE RISES INCREASING RAPIDLY FARTHER WEST.
PATCHY FOG MAINLY ALONG AND AHEAD OF THE FRONT CONTINUES BUT
IMPROVING CONDITIONS HAVE BEGUN AS EXPECTED FROM PREVIOUS FORECAST.
AREA OF SHOWERS AND ISOLATED THUNDERSTORMS IN NORTHEAST MONTANA
ALSO WEAKENING WITH TIME AS THEY MOVE INTO NORTHWESTERN NORTH
DAKOTA. THE LATEST HRRR AND RAP13 SHOW THESE SHOWERS WANING
THROUGH THE MORNING HOURS BEFORE ENDING BETWEEN 16Z-17Z. OVERALL
THE CURRENT GRIDDED FORECAST IN ON TRACK.
UPDATE ISSUED AT 609 AM CDT FRI JUL 11 2014
AREA OF SHOWERS AND THUNDERSTORMS OVER NORTHEAST MONTANA NEAR
RIGHT ENTRANCE REGION OF UPPER JET KEEP TRYING TO PUSH EAST...BUT
STRUGGLE TO HOLD TOGETHER ONCE THEY APPROACH THE STATE LINE.
EXPECT A FEW WILL START TO HOLD TOGETHER SO WILL MAINTAIN LOW POPS
AND PUSH THE POPS EAST A LITTLE. PATCHY FOG CONTINUES OVER THE
AREA...BUT EXPECT THIS TO IMPROVE NOT LONG AFTER SUNRISE. UPDATES
HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT FRI JUL 11 2014
MAIN FORECAST HIGHLIGHT IN THE SHORT TERM PERIOD WILL BE THE
CHANCE FOR SHOWERS AND THUNDERSTORMS NOW THROUGH TONIGHT.
CURRENTLY...FRONTAL BOUNDARY CONTINUES TO MOVE SLOWLY SOUTH AND
EAST ACROSS THE STATE...NOW POSITIONED ACROSS CENTRAL NORTH
DAKOTA. THE OUTFLOW BOUNDARY WHICH EARLIER PRODUCED A FEW
STRONGER STORMS NORTH CENTRAL...CONTINUES TO GENERATE WEAK
CONVECTION AS IT MOVES SOUTH. PAST HOUR HAVE SEEN WEAK ECHOS
DEVELOP ACROSS SHERIDAN AND NORTHERN BURLEIGH COUNTIES. WILL
MAINTAIN A MENTION OF SHOWERS/THUNDERSTORMS FOR THESE AREAS AND
ACROSS MY SOUTHEAST THROUGH 12Z FOR THIS FEATURE. ADDITIONAL
SHOWERS AND THUNDERSTORMS DEVELOPED THE PAST FEW HOURS ACROSS
NORTHERN MONTANA UNDER THE RIGHT ENTRANCE REGION OF AN UPPER LEVEL
JET STREAK MOVING SLOWLY EAST ALONG THE INTERNATIONAL BORDER.
SOME OF THIS ACTIVITY MAY ENTER WESTERN NORTH DAKOTA...MAINLY AFTER
12Z.
WILL ALSO MAINTAIN PATCHY FOG WORDING THROUGH 15Z BASED ON LATEST
OBSERVATIONS.
FOR TODAY...FORCING ASSOCIATED WITH THE UPPER JET STREAK REALLY
DOES NOT MATERIALIZE ACROSS NORTH DAKOTA UNTIL TONIGHT WHEN
DIVERGENCE ALOFT INCREASES. MAY SEE SOME ELEVATED
SHOWERS/THUNDERSTORMS THIS MORNING/AFTERNOON WEST...BUT DOES APPEAR
MOST SHOWER/THUNDERSTORM ACTIVITY WILL NOT GET GOING UNTIL AFTER
00Z. WHEN IT DOES...EXPECT PRECIPITATION TO BE CONFINED TO THE
SOUTHERN ONE HALF...IF NOT SOUTHERN ONE THIRD...WITH SUBSIDENCE
ASSOCIATED WITH SURFACE HIGH PRESSURE OVER MY NORTH. THE THREAT
FOR SEVERE WEATHER SHOULD REMAIN OFF TO OUR SOUTH WITH MODELS
INDICATING A STABLE AIRMASS OVER MUCH OF THE STATE. THE FAR SOUTH
WILL SEE THE BEST CHANCE FOR A STRAY STRONGER STORM OR
TWO...MAINLY LATE THIS AFTERNOON OR EVENING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI JUL 11 2014
ON SATURDAY...DEEPENING UPPER LOW SLIDES DOWN THE WESTERN SHORES OF
HUDSON BAY WHILE A FEW WAVES CONTINUE TO SWING THROUGH CYCLONIC FLOW
ALOFT THRU THE AREA. THIS WILL KEEP CHANCES FOR SHOWERS/STORMS IN
THE FORECAST PRIMARILY OVER SOUTHERN NORTH DAKOTA.
SUNDAY INTO MONDAY...AFOREMENTIONED UPPER LOW CONTINUES ITS
SOUTHERLY SLIDE TOWARDS NORTHERN MINNESOTA/LAKE SUPERIOR. MODELS
CONTINUE TO BE IN PRETTY GOOD AGREEMENT WITH THE TRACK OF THIS
SYSTEM. COOLER AIRMASS SWINGING AROUND THE LOW WILL PUSH INTO THE
AREA...WITH THE MAIN PUSH COMING LATE SUNDAY INTO MONDAY. THIS WILL
BRING WELL BELOW AVERAGE TEMPS TO THE REGION EARLY NEXT WEEK...WITH
MOST LOCATIONS SEEING HIGHS AROUND 15 TO 20 DEGREES BELOW AVERAGE ON
MONDAY. WILL HAVE TO WATCH THE TREND WITH THIS AS TEMPS MAY NEED TO
BE LOWERED EVEN FURTHER. A FEW SHOWERS WILL BE POSSIBLE ON MONDAY AS
VARIETY OF WAVES WRAP THROUGH CYCLONIC FLOW...PARTICULARLY FROM THE
TURTLE MOUNTAINS TO THE JAMES RIVER VALLEY.
FOR THE REMAINDER OF THE EXTENDED...UPPER LOW MOVES OFF TO THE EAST
WHILE RIDGE OVER THE WESTERN CONUS KEEPS NORTHWEST FLOW OVER OUR
AREA KEEPING CONDITIONS MAINLY DRY. TEMPERATURES WILL WARM THROUGH
MID-WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 609 AM CDT FRI JUL 11 2014
LCL IFR VIS IN FG OVER WRN/CNTRL ND WILL IMPROVE BY MID-MORNING.
ISOLD SHRA/-TSRA WILL CONTINUE OVER WRN ND THIS MORN...POSSIBLY
INTO THE AFTERNOON. ISOLD/SCT SHRA/-TSRA WILL BE POSSIBLE OVER SRN
ND TONIGHT. OTHERWISE...VFR CONDITIONS ARE EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...JJS
AVIATION...JJS
AREA FORECAST DISCUSSION...CORRECTED
NWS MEDFORD OR
507 AM PDT FRI JUL 11 2014
.DISCUSSION...VERY WARM TEMPERATURES WILL CONTINUE INTO THE
WEEKEND AS THE UPPER LEVEL RIDGE WILL ONLY WEAKEN TEMPORARILY. A
LOW PRESSURE TROUGH APPROACHING NORTHERN CALIFORNIA COAST THIS
MORNING WILL SEND A BAND OF MOISTURE INTO OUR FORECAST AREA ALONG
WITH AREAS OF INSTABILITY. SO FAR THERE HAVE BEEN CLOUD TO CLOUD
LIGHTNING STRIKES JUST SOUTH OF SISKIYOU COUNTY OVERNIGHT.
MOISTURE IS EXPECTED TO SPREAD INTO EASTERN SISKIYOU COUNTY MAINLY
FROM THE CASCADES EASTWARD AROUND DAY BREAK. THE NAM12 TAKES MOST
OF THIS MOISTURE NORTH ALONG AND JUST EAST OF THE CASCADES WITH
ANOTHER BAND OF MOISTURE ROTATING BACK ACROSS SW OREGON. THE SHORT
TERM HRRR MODEL SHOWS A SIMILAR TRACK ON FORECAST RADAR RETURN BUT
SHOWS A MODERATE RETURN (30-40DBZ) EXPANDING BACK INTO NW JACKSON
COUNTY AND EASTERN DOUGLAS COUNTY INTO FIRE ZONE 617 BY THIS
AFTERNOON. THE NAM12 SHOWS MORE INSTABILITY FURTHER WEST INTO
JOSEPHINE AND JACKSON COUNTY WHERES THE GFS KEEPS NEGATIVE LIFTED
INDEX MAINLY NEAR THE CASCADES WHILE ERODING ANY CAPPING BY MID
MORNING. MY FEELING ON THIS IS THAT WE MAY SEE TWO DISTINCT BAND
OF CONVECTION, ONE TRAVELLING NORTH INTO THE KLAMATH BASIN AND THE
OTHER COMING UP THROUGH THE HAPPY CAMP DISTRICT INTO THE ILLINOIS
VALLEY AND THEN NORTHWARD INTO THE UMPQUA BASIN. CURRENT RED FLAG
WARNING COVERS THIS TREND AND WILL KEEP AREAL COVERAGE AS IS. BOTH
MODELS SHOW CLEARING ACROSS THE WEST SIDE THIS AFTERNOON AND THIS
MAY BE CONDUCIVE TO THE SECOND ROUND OF CONVECTION FROM SURFACE
HEATING.
FOR SATURDAY..THERE WILL BE MORE H7-H5 MOISTURE EAST OF THE
CASCADES AND THIS IS WHERE MOST CONVECTION WILL BE LOCATED. THE
AIR MASS WILL BE MUCH DRIER WEST OF THE CASCADES. HAVE KEPT ALL OF
THUNDERSTORMS FORECAST TO THE EAST OF THE CASCADES.
ON SUNDAY..ANOTHER ROUND OF TROUGH WILL APPROACH THE COAST AGAIN.
ONE THING THAT MAKES THIS TROUGH DIFFERENT IS THE PRESENCE OF 75KT
JETMAX MOVING INTO NW CALIFORNIA AND SW OREGON. IN ADDITION BOTH
MODELS INDICATE ENOUGH MOISTURE TO GENERATE THUNDERSTORMS. /FB
&&
.AVIATION...BASED ON THE 11/06Z TAFS...IFR CONDITIONS
ARE PRESENT ALONG THE COAST AND ARE EXPECTED TO PERSIST THROUGH
EARLY THIS MORNING...WITH CLEARING IN THE LATE FRIDAY MORNING.
ELSEWHERE...EXPECT MAINLY VFR CONDITIONS EARLY THIS MORNING THEN AS
THUNDERSTORMS DEVELOP MAY SEE LOCAL MVFR CIGS DEVELOP DURING THE DAY
WITH A RETURN TO VFR DURING THE EVENING. THUNDERSTORMS WILL HAVE
THE LARGEST IMPACT ON INLAND AREAS TODAY. THUNDERSTORMS WILL AFFECT
NORTHERN CALIFORNIA FIRST EARLY THIS MORNING...AND THEN SPREAD INTO
SOUTHERN OREGON DURING THE MORNING AND CONTINUING INTO THE
AFTERNOON. GREATEST COVERAGE OF THUNDERSTORMS EXPECTED
LATE IN THE MORNING INTO THE AFTERNOON. VERY GUSTY WINDS AND HAIL
ARE EXPECTED WITH SOME OF THESE STORMS. /CC
&&
.MARINE...UPDATED THURSDAY 11 JULY 300 AM PDT...WINDS HAVE
WEAKENED CONSIDERABLY...AND SEAS WILL GRADUALLY DIMINISH THROUGH
TODAY. SEAS ARE COMING DOWN A BIT SLOWER THAN PREVIOUSLY
FORECAST...SO HAVE EXTENDED THE SMALL CRAFT ADVISORY OUT A FEW MORE
HOURS. A WEAK LOW PRESSURE WILL MOVE THROUGH THE WATERS TODAY INTO
TOMORROW...BUT WINDS WILL REMAIN GENERALLY LIGHT UNTIL SUNDAY
AFTERNOON. THE THERMAL TROUGH PATTERN WILL REDEVELOP SUNDAY AND
STRENGTHEN MONDAY...RESULTING IN ANOTHER ROUND OF MODERATE TO
STRONG NORTH WINDS AND BUILDING SHORT PERIOD SEAS. -BPN
&&
.FIRE WEATHER...SATELLITE AND RADAR IMAGERY TO THE SOUTH SHOW SOME
CONVECTION HAS BEGUN IN ASSOCIATION WITH A SHORT WAVE AND MONSOONAL
MOISTURE THAT WILL BE MOVING INTO OUR AREA LATER THIS MORNING
THROUGH THIS AFTERNOON. SOME CLOUD-TO-CLOUD LIGHTNING HAS ALSO BEEN
DEPICTED WITH THESE BUILDUPS...SUGGESTING THAT A GOOD DEAL OF
INSTABILITY EXISTS OVER THE AREA THIS MORNING EVEN BEFORE SOLAR
HEATING BEGINS. MUCH DEPENDS ON THE TIMING OF THE SHORTWAVE AND THE
ARRIVAL OF MOISTURE...AS WELL AS WHAT AREAS RECEIVE THE MOST
HEATING...AND THE EXACT LOCATION OF JET ENERGY OVERHEAD WHICH COULD
LEND TO MORE NUMEROUS CELLS. STEERING WINDS ARE EXPECTED TO BE FROM
THE SOUTH AND SOUTHEAST WHICH IS A FAVORABLE FLOW TO GET STORMS TO
SPREAD OUT OVER THE VALLEYS WEST OF THE CASCADES. GIVEN THE DRY
FUELS AND EXPECTED NUMEROUS LIGHTNING STRIKES EXPECTED...HAVE
CONTINUED RED FLAG WARNINGS FOR NORTHERN CAL AND MOST OF OREGON
ZONES. THE EXCEPTION WILL BE THE COASTAL ZONES...WHERE THE
ATMOSPHERE SHOULD REMAIN MUCH MORE STABLE. EVEN THEN...CAN NOT RULE
OUT ISOLATED THUNDERSTORMS FOR FIRE ZONES 615 AND 618. MODELS
SUGGEST THE BULK OF THE ACTION WILL SHIFT NORTH DURING THE DAY TODAY
AND COULD BE OUT OF THE AREA BY THIS AFTERNOON...BUT AGAIN MUCH
DEPENDS ON THE TIMING. ANOTHER UPPER LOW WILL MOVE TOWARDS THE AREA
SUNDAY, BUT THE MODELS SUGGEST MOST OF THE INSTABILITY AND
THUNDERSTORM POTENTIAL WILL BE FROM AROUND CRATER LAKE NORTH. -BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR ORZ624-625.
RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR
ORZ616-617-619>623.
CA...RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR
CAZ280>282-284-285.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT THIS
MORNING FOR PZZ350-356-370-376.
$$
FJB/FJB/CC
AREA FORECAST DISCUSSION
NWS MEDFORD OR
339 AM PDT FRI JUL 11 2014
.DISCUSSION...VERY WARM TEMPERATURES WILL CONTINUE INTO THE
WEEKEND AS THE UPPER LEVEL RIDGE WILL ONLY WEAKEN BUT NOT BROKEN.
A LOW PRESSURE TROUGH APPROACHING NORTHERN CALIFORNIA COAST THIS
MORNING WILL SEND A BAND OF MOISTURE INTO OUR FORECAST AREA ALONG
WITH AREAS OF INSTABILITY. SO FAR THERE HAVE BEEN CLOUD TO CLOUD
LIGHTNING STRIKES JUST SOUTH OF SISKIYOU COUNTY OVERNIGHT.
MOISTURE IS EXPECTED TO SPREAD INTO EASTERN SISKIYOU COUNTY MAINLY
FROM THE CASCADES EASTWARD AROUND DAY BREAK. THE NAM12 TAKES MOST
OF THIS MOISTURE NORTH ALONG AND JUST EAST OF THE CASCADES WITH
ANOTHER BAND OF MOISTURE ROTATING BACK ACROSS SW OREGON. THE SHORT
TERM HRRR MODEL SHOWS A SIMILAR TRACK ON FORECAST RADAR RETURN BUT
SHOWS A MODERATE RETURN (30-40DBZ) EXPANDING BACK INTO NW JACKSON
COUNTY AND EASTERN DOUGLAS COUNTY INTO FIRE ZONE 617 BY THIS
AFTERNOON. THE NAM12 SHOWS MORE INSTABILITY FURTHER WEST INTO
JOSEPHINE AND JACKSON COUNTY WHERES THE GFS KEEPS NEGATIVE LIFTED
INDEX MAINLY NEAR THE CASCADES WHILE ERODING ANY CAPPING BY MID
MORNING. MY FEELING ON THIS IS THAT WE MAY SEE TWO DISTINCT BAND
OF CONVECTION, ONE TRAVELLING NORTH INTO THE KLAMATH BASIN AND THE
OTHER COMING UP THROUGH THE HAPPY CAMP DISTRICT INTO THE ILLINOIS
VALLEY AND THEN NORTHWARD INTO THE UMPQUA BASIN. CURRENT RED FLAG
WARNING COVERS THIS TREND AND WILL KEEP AREAL COVERAGE AS IS. BOTH
MODELS SHOW CLEARING ACROSS THE WEST SIDE THIS AFTERNOON AND THIS
MAY BE CONDUCIVE TO THE SECOND ROUND OF CONVECTION FROM SURFACE
HEATING.
FOR SATURDAY..THERE WILL BE MORE H7-H5 MOISTURE EAST OF THE
CASCADES AND THIS IS WHERE MOST CONVECTION WILL BE LOCATED. THE
AIR MASS WILL BE MUCH DRIER WEST OF THE CASCADES. HAVE KEPT ALL OF
THUNDERSTORMS FORECAST TO THE EAST OF THE CASCADES.
ON SUNDAY..ANOTHER ROUND OF TROUGH WILL APPROACH THE COAST AGAIN.
ONE THING THAT MAKES THIS TROUGH DIFFERENT IS THE PRESENCE OF 75KT
JETMAX MOVING INTO NW CALIFORNIA AND SW OREGON. IN ADDITION BOTH
MODELS INDICATE ENOUGH MOISTURE TO GENERATE THUNDERSTORMS. /FB
&&
.AVIATION...BASED ON THE 11/06Z TAFS...IFR CONDITIONS
ARE PRESENT ALONG THE COAST AND ARE EXPECTED TO PERSIST THROUGH
EARLY THIS MORNING...WITH CLEARING IN THE LATE FRIDAY MORNING.
ELSEWHERE...EXPECT MAINLY VFR CONDITIONS EARLY THIS MORNING THEN AS
THUNDERSTORMS DEVELOP MAY SEE LOCAL MVFR CIGS DEVELOP DURING THE DAY
WITH A RETURN TO VFR DURING THE EVENING. THUNDERSTORMS WILL HAVE
THE LARGEST IMPACT ON INLAND AREAS TODAY. THUNDERSTORMS WILL AFFECT
NORTHERN CALIFORNIA FIRST EARLY THIS MORNING...AND THEN SPREAD INTO
SOUTHERN OREGON DURING THE MORNING AND CONTINUING INTO THE
AFTERNOON. GREATEST COVERAGE OF THUNDERSTORMS EXPECTED
LATE IN THE MORNING INTO THE AFTERNOON. VERY GUSTY WINDS AND HAIL
ARE EXPECTED WITH SOME OF THESE STORMS. /CC
&&
.MARINE...UPDATED THURSDAY 11 JULY 300 AM PDT...WINDS HAVE
WEAKENED CONSIDERABLY...AND SEAS WILL GRADUALLY DIMINISH THROUGH
TODAY. SEAS ARE COMING DOWN A BIT SLOWER THAN PREVIOUSLY
FORECAST...SO HAVE EXTENDED THE SMALL CRAFT ADVISORY OUT A FEW MORE
HOURS. A WEAK LOW PRESSURE WILL MOVE THROUGH THE WATERS TODAY INTO
TOMORROW...BUT WINDS WILL REMAIN GENERALLY LIGHT UNTIL SUNDAY
AFTERNOON. THE THERMAL TROUGH PATTERN WILL REDEVELOP SUNDAY AND
STRENGTHEN MONDAY...RESULTING IN ANOTHER ROUND OF MODERATE TO
STRONG NORTH WINDS AND BUILDING SHORT PERIOD SEAS. -BPN
&&
.FIRE WEATHER...SATELLITE AND RADAR IMAGERY TO THE SOUTH SHOW SOME
CONVECTION HAS BEGUN IN ASSOCIATION WITH A SHORT WAVE AND MONSOONAL
MOISTURE THAT WILL BE MOVING INTO OUR AREA LATER THIS MORNING
THROUGH THIS AFTERNOON. SOME CLOUD-TO-CLOUD LIGHTNING HAS ALSO BEEN
DEPICTED WITH THESE BUILDUPS...SUGGESTING THAT A GOOD DEAL OF
INSTABILITY EXISTS OVER THE AREA THIS MORNING EVEN BEFORE SOLAR
HEATING BEGINS. MUCH DEPENDS ON THE TIMING OF THE SHORTWAVE AND THE
ARRIVAL OF MOISTURE...AS WELL AS WHAT AREAS RECEIVE THE MOST
HEATING...AND THE EXACT LOCATION OF JET ENERGY OVERHEAD WHICH COULD
LEND TO MORE NUMEROUS CELLS. STEERING WINDS ARE EXPECTED TO BE FROM
THE SOUTH AND SOUTHEAST WHICH IS A FAVORABLE FLOW TO GET STORMS TO
SPREAD OUT OVER THE VALLEYS WEST OF THE CASCADES. GIVEN THE DRY
FUELS AND EXPECTED NUMEROUS LIGHTNING STRIKES EXPECTED...HAVE
CONTINUED RED FLAG WARNINGS FOR NORTHERN CAL AND MOST OF OREGON
ZONES. THE EXCEPTION WILL BE THE COASTAL ZONES...WHERE THE
ATMOSPHERE SHOULD REMAIN MUCH MORE STABLE. EVEN THEN...CAN NOT RULE
OUT ISOLATED THUNDERSTORMS FOR FIRE ZONES 615 AND 618. MODELS
SUGGEST THE BULK OF THE ACTION WILL SHIFT NORTH DURING THE DAY TODAY
AND COULD BE OUT OF THE AREA BY THIS AFTERNOON...BUT AGAIN MUCH
DEPENDS ON THE TIMING. ANOTHER UPPER LOW WILL MOVE TOWARDS THE AREA
SUNDAY, BUT THE MODELS SUGGEST MOST OF THE INSTABILITY AND
THUNDERSTORM POTENTIAL WILL BE FROM AROUND CRATER LAKE NORTH. -BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR ORZ624-625.
RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR
ORZ616-617-619>623.
CA...RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR
CAZ280>282-284-285.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT THIS
MORNING FOR PZZ350-356-370-376.
$$
FJB/FJB/CC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
844 AM CDT FRI JUL 11 2014
.UPDATE...
ISSUED AT 844 AM CDT FRI JUL 11 2014
FORECAST HAS BEEN UPDATED TO RAISE POPS CONSIDERABLY THROUGH THE
MORNING HOURS AS THE REMNANTS OF AN OVERNIGHT CONVECTIVE SYSTEM
TRACK TO THE EAST THROUGH THE REGION...PARTICULARLY IN SOUTHEAST
MINNESOTA AND WESTERN WISCONSIN. INSTABILITY REMAINS FAIRLY
WEAK...SO ANY THUNDERSTORMS SHOULD REMAIN FAIRLY ISOLATED. NOT
SURE HOW MUCH ACTIVITY WILL REDEVELOP IN THE AFTERNOON AS THIS
FEATURE MOVES OFF TO THE EAST BY THIS AFTERNOON. TEMPERATURES WILL
REMAIN DOWN DUE TO THE CLOUD COVER AND RAIN THIS MORNING...BUT
COULD MAKE A BRIEF REBOUND IN THE LATE AFTERNOON HOURS...SO HAVE
ADJUSTED THAT PART OF THE FORECAST AS WELL. UPDATES COMING
SHORTLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN SHORT TERM CONCERN IS ON PRECIPITATION CHANCES TODAY.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE CENTRAL U.S....A WEAK RIDGE OVER MICHIGAN...
A SHORTWAVE TROUGH CROSSING MN WITH THE CORE NEAR DULUTH...A WEAK
SHORTWAVE CROSSING NEBRASKA...AND A DEEP UPPER TROUGH OVER SOUTH
CENTRAL CANADA. DPVA AHEAD OF THE MN SHORTWAVE TROUGH COMBINED WITH
850MB MOISTURE TRANSPORT SEEN BY STRONGER 850MB WINDS ON RADARS FROM
EASTERN SOUTH DAKOTA INTO NORTHERN MN HAS SUPPORTED SHOWERS AND
STORMS NORTH OF MINNEAPOLIS. THE NEBRASKA SHORTWAVE AND ANOTHER NOSE
OF 850MB MOISTURE TRANSPORT HAS SUPPORTED OTHER SHORTWAVES AND
STORMS FROM NEBRASKA INTO SIOUX FALLS AREA. THE FORECAST AREA
MEANWHILE HAS ONLY SEEN A FEW LIGHT SHOWERS WEST OF THE MS RIVER
STEMMING FROM ACCAS CLOUDS ON THE EASTERN EXTENT OF THE MOISTURE
TRANSPORT ZONE. THE AIRMASS OVER THE REGION HAS CERTAINLY BECOME
WARMER AND MORE MOIST OVER THE PAST 24 HOURS. 850MB TEMPS HAVE
CLIMBED TO 12-15C ACCORDING TO 00Z SOUNDINGS WITH 20-25C READINGS IN
THE DAKOTAS. MEANWHILE...PRECIPITABLE WATER VALUES ARE UP TO 1-1.5
INCHES WITH A 2 INCH MAXIMA NEAR SIOUX FALLS PER RAP AND GOES
DERIVED.
THE FORECAST FOR TODAY IS RADICALLY DRIER THAN WHAT IT LOOKED LIKE
24 HOURS AGO. MUCH OF THIS IS A FUNCTION OF THE 850MB MOISTURE
TRANSPORT BEING INCORRECT. INSTEAD OF THE NOSE COMING RIGHT AT THE
FORECAST AREA...ITS IN NORTHERN MN AND NEAR SIOUX FALLS.
ADDITIONALLY...THE SHORTWAVE TRACKING ACROSS MN IS MOVING FASTER
THAN EARLIER PROJECTIONS.
RE-ANALYZING TODAYS FORECAST. IT APPEARS THE SHOWERS AND STORMS
TAKING PLACE NORTH OF MINNEAPOLIS WILL PROGRESS TO THE EAST THIS
MORNING WITH THE CORE OF THE SHORTWAVE TROUGH...PERHAPS CLIPPING
TAYLOR COUNTY. TO THE WEST...REGARDING THE SHOWERS AND STORMS
CROSSING NEBRASKA AND SIOUX FALLS...THESE MAY MAKE IT INTO NORTHEAST
IOWA LATE IN THE MORNING PER HRRR AND 11.00Z GFS PROGS. HOWEVER...
THE 850MB MOISTURE TRANSPORT NOSE SUPPORTING THEM IS PROGGED TO
DRAMATICALLY WEAKEN IN ALL MODELS...SO ITS POSSIBLE THEY DIE BEFORE
REACHING NORTHEAST IOWA. THIS LEAVES REALLY THE ONLY OTHER THREAT OF
PRECIPITATION FOR THE MORNING BEING THIS ACCAS WHICH COULD SHOWER
HERE AND THERE ACROSS MUCH OF THE FORECAST AREA DURING THE MORNING.
HEADING INTO THE AFTERNOON...DESPITE THE FACT THAT THE HIGHER
PRECIPITABLE WATER ZONE OVER SIOUX FALLS AREA IS PROGGED TO SHIFT
EAST INTO THE AREA...THERES NO FORCING TO DO ANYTHING WITH THAT
MOISTURE. SURFACE BOUNDARY WISE...A COLD FRONT LOOKS TO EXTEND
SOUTHWEST TO NORTHEAST ACROSS MN WHILE A WARM FRONT IS ACROSS
NEBRASKA...BOTH BEING WEST OF THE AREA. ADDITIONALLY...500MB HEIGHTS
ARE RISING IN THE WAKE OF THE SHORTWAVE TROUGH TO PROVIDE
SUBSIDENCE. 11.00Z NAM/GFS/REGIONAL CANADIAN ARE ALL DRY AND HAVE
TRENDED THE FORECAST EVEN MORE IN THAT DIRECTION. ONLY THE 11.00Z
HIRES ARW HAS SOME ISOLATED DIURNAL CONVECTION SO KEPT A 20 PERCENT
CHANCE IN CASE. WITH A DRIER FORECAST AND 850MB TEMPS BETWEEN 14-16C
TODAY...HAVE RAISED TEMPERATURES A FEW DEGREES. PLENTY OF MID CLOUD
WILL HAMPER HIGHS FROM REACHING FULL POTENTIAL...THOUGH.
FOR TONIGHT...THERE IS GOOD MODEL AGREEMENT FOR 850MB MOISTURE
TRANSPORT TO INCREASE ACROSS THE CENTRAL PLAINS INTO THE I-80
CORRIDOR ACROSS NEBRASKA AND IOWA. THE CAUSE FOR THE INCREASE IS
TIED TO A FAIRLY STRONG MONSOONAL SHORTWAVE SEEN ON WATER VAPOR
IMAGERY OVER LAS VEGAS...ROTATING UP AROUND THE CENTRAL PLAINS RIDGE
INTO SOUTH DAKOTA BY 12Z SATURDAY. GIVEN THE HIGH PRECIPITABLE WATER
AIRMASS IN PLACE...IT SEEMS ALL BUT CERTAIN SHOWERS AND
THUNDERSTORMS WILL FIRE ON THE NOSE OF THAT 850MB MOISTURE TRANSPORT
ZONE. SOME OF THESE STORMS COULD WORK INTO LOCATIONS SOUTH OF
INTERSTATE 90 AFTER MIDNIGHT...THOUGH BELIEVE THE GREATER FOCUS FOR
THEM WILL OCCUR SOUTH AND WEST OF THE AREA PRIOR TO 12Z SATURDAY.
ALSO CANNOT RULE OUT A FEW SHOWERS AND STORMS THROUGH THE NIGHT
CROSSING TAYLOR/CLARK COUNTIES FROM THE COLD FRONT OVER MN TRACKING
THROUGH THERE. WITH A HIGH PRECIPITABLE WATER AIRMASS IN PLACE AND
MID CLOUD SPREADING IN FROM THE SOUTHWEST...ANTICIPATING A WARM
NIGHT. IN FACT...HIGHER DEWPOINTS ADVECTING IN COULD RESULT IN SOME
FOG.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN LONG TERM CONCERNS ARE ON SEVERE WEATHER POTENTIAL SATURDAY
AFTERNOON/EVENING AND THE UNSEASONABLY COLD AIR MONDAY INTO TUESDAY.
SATURDAYS FOCUS IS ENTIRELY ON THE CURRENT MONSOONAL SHORTWAVE NEAR
LAS VEGAS. MODEL CONSENSUS BRINGS THIS SHORTWAVE THROUGH OUR AREA AT
ABOUT THE TIME OF PEAK HEATING. 0-6KM...0-3KM AND 0-1KM SHEAR VALUES
ALL REALLY INCREASE THROUGH THE DAY IN RESPONSE TO THE SHORTWAVE...
TOPPING OUT AT 21Z AROUND 60 KTS...45 KT AND 20-25 KT RESPECTIVELY.
THIS IS PLENTY FOR ORGANIZED SEVERE CONVECTION. THE DEEPER SHEAR IS
ALSO NICELY CYCLONICALLY CURVED. MEANWHILE...THE ATMOSPHERE IS
JUICED UP PRECIPITABLE WATER WISE WITH VALUES OF 2 INCHES GETTING
ADVECTED INTO THE AREA. ALSO GOOD MODEL CONSENSUS EXISTS FOR 750-
2000 J/KG OF MLCAPE TO BUILD UP SOUTH OF I-90...LIMITED BY PLENTIFUL
CLOUD COVER...WITH EVEN HIGHER VALUES BUILDING UP IN A CAPPED
AIRMASS NEAR I-80. THUS...SEE SOME CHANCE FOR A SEVERE WEATHER EVENT
SATURDAY AFTERNOON. HAIL THREAT IS LIMITED BY THE HIGH PRECIPITABLE
WATER AND WARM CLOUD DEPTHS AROUND 4 KM. THESE PARAMETERS INCREASE
THE HEAVY RAIN AND FLASH FLOODING CONCERN...HOWEVER...THE STRONG
SHEAR SHOULD PROMOTE PROGRESSIVE CONVECTION. ADDITIONALLY...THE
RECENT DRY PERIOD WILL ALLOW SOILS TO ABSORB MORE WATER. THE STRONG
SHEAR DEFINITELY MAKES DAMAGING WINDS A CONCERN. CANNOT RULE OUT A
TORNADO EITHER GIVEN THE 0-1KM SHEAR AND A WARM FRONT LIKELY TO SIT
NEAR/SOUTH OF US-20. REALLY THE ONLY ISSUE WITH SATURDAY AMONGST THE
MODELS IS THE PLACEMENT OF AFTERNOON CONVECTION. THE 11.00Z
NAM/REGIONAL CANADIAN ARE ALONG/NORTH OF I-90...WHICH BOTH HAVE HAD
A NORTHWARD BIAS TO SEVERE CONVECTIVE EVENTS THIS YEAR. PREFER THE
FARTHER SOUTH 11.00Z GFS/ECMWF/HIRES ARW. MUCH OF THE CONVECTION
SHOULD PUSH SOUTHEAST OF THE AREA BY 03Z WITH THE PASSAGE OF THE
SHORTWAVE...FOLLOWED BY SIGNIFICANT DRYING OF PRECIPITABLE WATER OF
NEARLY 1 INCH BY 12Z SUNDAY.
ON SUNDAY...THE DEEP UPPER TROUGH OVER SOUTH CENTRAL CANADA IS
PROGGED TO BEGIN ITS DESCENT INTO OUR REGION. A COLD FRONT AHEAD OF
THE TROUGH SHOULD DROP SOUTH THROUGH THE AREA...AGAIN AT THE TIME OF
PEAK HEATING. 0-6KM SHEAR IS RUNNING 40-50 KT WITH 0-3KM AT 25-35KT.
HOWEVER...INSTABILITY LOOKS TO BE SEVERELY LACKING RESULTING FROM THE
SIGNIFICANT DRYING OF PRECIPITABLE WATER SATURDAY NIGHT. 11.00Z GFS
HAS THE GREATEST INSTABILITY AT 500-1000 J/KG OF MLCAPE...BUT THINK
ITS DEWPOINTS IN THE LOW 60S POOLING AROUND THE BOUNDARY ARE TOO
HIGH. FOR NOW HAVE CONTINUED SOME CHANCES OF PRECIPITATION FOR THE
FRONT...BUT BELIEVE THE DRIER 11.00Z ECMWF/CANADIAN/NAM WILL COME
TRUE. MUCH COOLER AND DRIER AIR SINKS SOUTH INTO THE AREA SUNDAY
NIGHT IN THE WAKE OF THE FRONT.
MONDAY AND TUESDAY STILL LOOK LIKE A TASTE OF FALL AS A SHOT OF
MODIFIED ARCTIC AIR COMES INTO THE REGION. AN UPPER LOW WITHIN THE
DEEP UPPER TROUGH IS PROGGED TO SLIDE ACROSS NORTHERN WI MONDAY
EVENING. COOL TEMPERATURES ALOFT...DAYTIME HEATING AND DPVA AHEAD OF
THE UPPER LOW SHOULD PROMOTE SHOWER DEVELOPMENT ACROSS MUCH OF THE
REGION MONDAY. THIS WILL BE ESPECIALLY TRUE OVER NORTHERN WI. HAVE
RAISED PRECIPITATION CHANCES AND FURTHER INCREASES MAY BE NECESSARY.
PRECIPITATION CHANCES CONTINUE INTO TUESDAY AS WELL WITH THE COLD
AIR ALOFT STILL AROUND. 850MB TEMPERATURES PLUMMET TO 4-6C ON MONDAY
ON A BREEZY NORTHWEST WIND AND HOLD THERE THROUGH TUESDAY. THESE ARE
2-2.5 STANDARD DEVIATIONS BELOW NORMAL SUGGESTING RECORDS ARE
POSSIBLE. SEE CLIMATE SECTION BELOW FOR MORE DETAILS.
THE WEATHER QUIETS DOWN THEN FOR WEDNESDAY AND THROUGH THE END OF
THE WEEK AS THE DEEP UPPER TROUGH GRADUALLY EJECTS OUT. PLENTIFUL
DRY CANADIAN AIR PLUNGES SOUTH THROUGH MUCH OF THE EASTERN U.S....
RESULTING IN A DRY FORECAST FOR WEDNESDAY AND BEYOND. TEMPERATURES
WILL GRADUALLY WARM EACH DAY AS THE SUN HELPS MODIFY THE COLD AIR.
WE SHOULD BE BACK CLOSE TO NORMAL BY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 635 AM CDT FRI JUL 11 2014
FORCING REMAINS WEAK ACROSS THE AREA TODAY AND THE BULK OF THE
MOISTURE AT AND ABOVE 850MB. SCT SHRA EXPECTED TO SPREAD ACROSS THE
TAF SITES THIS MORNING INTO EARLY THIS AFTERNOON BUT MOST VSBYS TO
REMAIN 10SM WITH VFR CIGS. GRADIENT TIGHTENS OVER THE AREA TODAY AND
WITH DIURNAL WARMING/MIXING BRISK/GUSTY SOUTH TO SOUTHWEST WINDS
EXPECTED FOR THE LATE MORNING AND AFTERNOON HOURS TODAY.
MOISTURE CONTINUES TO INCREASE TONIGHT BUT SIGNALS FOR SHRA/TSRA
OVER THE AREA QUITE VARIED. MORE OF A SIGNAL FOR CONVECTION TO FIRE
WEST AND SOUTH OF THE TAF SITES TONIGHT SO LEFT VCTS/VCSH MENTIONS
OUT OF THE KRST/KLSE TAFS FOR NOW GIVEN LOW CONFIDENCE IN ANY SHRA/
TSRA IN THE AREA LATER TONIGHT. WITH THE INCREASING MOISTURE AND
APPROACH OF A SFC FRONT/TROUGH AXIS DID INCREASE THE LOWER CLOUDS
TONIGHT. CARRIED SOME MVFR BR AT KRST AND INCLUDED 4K-5K FT CIGS AT
BOTH KRST/KLSE AFTER 06-07Z FOR NOW.
&&
.CLIMATE...
ISSUED AT 255 AM CDT FRI JUL 11 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI
RIVER VALLEY. FORECAST HIGH TEMPERATURES FOR TUESDAY ARE 65 AT
ROCHESTER AND 66 AT LA CROSSE. THESE TEMPERATURES WOULD BREAK THE
RECORD LOWEST HIGH TEMPERATURES FOR JULY 15TH. THE OLD RECORDS ARE
68 AT LA CROSSE SET BACK IN 1962 AND 67 AT ROCHESTER ALSO SET
BACK IN 1962.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
CLIMATE......AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
635 AM CDT FRI JUL 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN SHORT TERM CONCERN IS ON PRECIPITATION CHANCES TODAY.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE CENTRAL U.S....A WEAK RIDGE OVER MICHIGAN...
A SHORTWAVE TROUGH CROSSING MN WITH THE CORE NEAR DULUTH...A WEAK
SHORTWAVE CROSSING NEBRASKA...AND A DEEP UPPER TROUGH OVER SOUTH
CENTRAL CANADA. DPVA AHEAD OF THE MN SHORTWAVE TROUGH COMBINED WITH
850MB MOISTURE TRANSPORT SEEN BY STRONGER 850MB WINDS ON RADARS FROM
EASTERN SOUTH DAKOTA INTO NORTHERN MN HAS SUPPORTED SHOWERS AND
STORMS NORTH OF MINNEAPOLIS. THE NEBRASKA SHORTWAVE AND ANOTHER NOSE
OF 850MB MOISTURE TRANSPORT HAS SUPPORTED OTHER SHORTWAVES AND
STORMS FROM NEBRASKA INTO SIOUX FALLS AREA. THE FORECAST AREA
MEANWHILE HAS ONLY SEEN A FEW LIGHT SHOWERS WEST OF THE MS RIVER
STEMMING FROM ACCAS CLOUDS ON THE EASTERN EXTENT OF THE MOISTURE
TRANSPORT ZONE. THE AIRMASS OVER THE REGION HAS CERTAINLY BECOME
WARMER AND MORE MOIST OVER THE PAST 24 HOURS. 850MB TEMPS HAVE
CLIMBED TO 12-15C ACCORDING TO 00Z SOUNDINGS WITH 20-25C READINGS IN
THE DAKOTAS. MEANWHILE...PRECIPITABLE WATER VALUES ARE UP TO 1-1.5
INCHES WITH A 2 INCH MAXIMA NEAR SIOUX FALLS PER RAP AND GOES
DERIVED.
THE FORECAST FOR TODAY IS RADICALLY DRIER THAN WHAT IT LOOKED LIKE
24 HOURS AGO. MUCH OF THIS IS A FUNCTION OF THE 850MB MOISTURE
TRANSPORT BEING INCORRECT. INSTEAD OF THE NOSE COMING RIGHT AT THE
FORECAST AREA...ITS IN NORTHERN MN AND NEAR SIOUX FALLS.
ADDITIONALLY...THE SHORTWAVE TRACKING ACROSS MN IS MOVING FASTER
THAN EARLIER PROJECTIONS.
RE-ANALYZING TODAYS FORECAST. IT APPEARS THE SHOWERS AND STORMS
TAKING PLACE NORTH OF MINNEAPOLIS WILL PROGRESS TO THE EAST THIS
MORNING WITH THE CORE OF THE SHORTWAVE TROUGH...PERHAPS CLIPPING
TAYLOR COUNTY. TO THE WEST...REGARDING THE SHOWERS AND STORMS
CROSSING NEBRASKA AND SIOUX FALLS...THESE MAY MAKE IT INTO NORTHEAST
IOWA LATE IN THE MORNING PER HRRR AND 11.00Z GFS PROGS. HOWEVER...
THE 850MB MOISTURE TRANSPORT NOSE SUPPORTING THEM IS PROGGED TO
DRAMATICALLY WEAKEN IN ALL MODELS...SO ITS POSSIBLE THEY DIE BEFORE
REACHING NORTHEAST IOWA. THIS LEAVES REALLY THE ONLY OTHER THREAT OF
PRECIPITATION FOR THE MORNING BEING THIS ACCAS WHICH COULD SHOWER
HERE AND THERE ACROSS MUCH OF THE FORECAST AREA DURING THE MORNING.
HEADING INTO THE AFTERNOON...DESPITE THE FACT THAT THE HIGHER
PRECIPITABLE WATER ZONE OVER SIOUX FALLS AREA IS PROGGED TO SHIFT
EAST INTO THE AREA...THERES NO FORCING TO DO ANYTHING WITH THAT
MOISTURE. SURFACE BOUNDARY WISE...A COLD FRONT LOOKS TO EXTEND
SOUTHWEST TO NORTHEAST ACROSS MN WHILE A WARM FRONT IS ACROSS
NEBRASKA...BOTH BEING WEST OF THE AREA. ADDITIONALLY...500MB HEIGHTS
ARE RISING IN THE WAKE OF THE SHORTWAVE TROUGH TO PROVIDE
SUBSIDENCE. 11.00Z NAM/GFS/REGIONAL CANADIAN ARE ALL DRY AND HAVE
TRENDED THE FORECAST EVEN MORE IN THAT DIRECTION. ONLY THE 11.00Z
HIRES ARW HAS SOME ISOLATED DIURNAL CONVECTION SO KEPT A 20 PERCENT
CHANCE IN CASE. WITH A DRIER FORECAST AND 850MB TEMPS BETWEEN 14-16C
TODAY...HAVE RAISED TEMPERATURES A FEW DEGREES. PLENTY OF MID CLOUD
WILL HAMPER HIGHS FROM REACHING FULL POTENTIAL...THOUGH.
FOR TONIGHT...THERE IS GOOD MODEL AGREEMENT FOR 850MB MOISTURE
TRANSPORT TO INCREASE ACROSS THE CENTRAL PLAINS INTO THE I-80
CORRIDOR ACROSS NEBRASKA AND IOWA. THE CAUSE FOR THE INCREASE IS
TIED TO A FAIRLY STRONG MONSOONAL SHORTWAVE SEEN ON WATER VAPOR
IMAGERY OVER LAS VEGAS...ROTATING UP AROUND THE CENTRAL PLAINS RIDGE
INTO SOUTH DAKOTA BY 12Z SATURDAY. GIVEN THE HIGH PRECIPITABLE WATER
AIRMASS IN PLACE...IT SEEMS ALL BUT CERTAIN SHOWERS AND
THUNDERSTORMS WILL FIRE ON THE NOSE OF THAT 850MB MOISTURE TRANSPORT
ZONE. SOME OF THESE STORMS COULD WORK INTO LOCATIONS SOUTH OF
INTERSTATE 90 AFTER MIDNIGHT...THOUGH BELIEVE THE GREATER FOCUS FOR
THEM WILL OCCUR SOUTH AND WEST OF THE AREA PRIOR TO 12Z SATURDAY.
ALSO CANNOT RULE OUT A FEW SHOWERS AND STORMS THROUGH THE NIGHT
CROSSING TAYLOR/CLARK COUNTIES FROM THE COLD FRONT OVER MN TRACKING
THROUGH THERE. WITH A HIGH PRECIPITABLE WATER AIRMASS IN PLACE AND
MID CLOUD SPREADING IN FROM THE SOUTHWEST...ANTICIPATING A WARM
NIGHT. IN FACT...HIGHER DEWPOINTS ADVECTING IN COULD RESULT IN SOME
FOG.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN LONG TERM CONCERNS ARE ON SEVERE WEATHER POTENTIAL SATURDAY
AFTERNOON/EVENING AND THE UNSEASONABLY COLD AIR MONDAY INTO TUESDAY.
SATURDAYS FOCUS IS ENTIRELY ON THE CURRENT MONSOONAL SHORTWAVE NEAR
LAS VEGAS. MODEL CONSENSUS BRINGS THIS SHORTWAVE THROUGH OUR AREA AT
ABOUT THE TIME OF PEAK HEATING. 0-6KM...0-3KM AND 0-1KM SHEAR VALUES
ALL REALLY INCREASE THROUGH THE DAY IN RESPONSE TO THE SHORTWAVE...
TOPPING OUT AT 21Z AROUND 60 KTS...45 KT AND 20-25 KT RESPECTIVELY.
THIS IS PLENTY FOR ORGANIZED SEVERE CONVECTION. THE DEEPER SHEAR IS
ALSO NICELY CYCLONICALLY CURVED. MEANWHILE...THE ATMOSPHERE IS
JUICED UP PRECIPITABLE WATER WISE WITH VALUES OF 2 INCHES GETTING
ADVECTED INTO THE AREA. ALSO GOOD MODEL CONSENSUS EXISTS FOR 750-
2000 J/KG OF MLCAPE TO BUILD UP SOUTH OF I-90...LIMITED BY PLENTIFUL
CLOUD COVER...WITH EVEN HIGHER VALUES BUILDING UP IN A CAPPED
AIRMASS NEAR I-80. THUS...SEE SOME CHANCE FOR A SEVERE WEATHER EVENT
SATURDAY AFTERNOON. HAIL THREAT IS LIMITED BY THE HIGH PRECIPITABLE
WATER AND WARM CLOUD DEPTHS AROUND 4 KM. THESE PARAMETERS INCREASE
THE HEAVY RAIN AND FLASH FLOODING CONCERN...HOWEVER...THE STRONG
SHEAR SHOULD PROMOTE PROGRESSIVE CONVECTION. ADDITIONALLY...THE
RECENT DRY PERIOD WILL ALLOW SOILS TO ABSORB MORE WATER. THE STRONG
SHEAR DEFINITELY MAKES DAMAGING WINDS A CONCERN. CANNOT RULE OUT A
TORNADO EITHER GIVEN THE 0-1KM SHEAR AND A WARM FRONT LIKELY TO SIT
NEAR/SOUTH OF US-20. REALLY THE ONLY ISSUE WITH SATURDAY AMONGST THE
MODELS IS THE PLACEMENT OF AFTERNOON CONVECTION. THE 11.00Z
NAM/REGIONAL CANADIAN ARE ALONG/NORTH OF I-90...WHICH BOTH HAVE HAD
A NORTHWARD BIAS TO SEVERE CONVECTIVE EVENTS THIS YEAR. PREFER THE
FARTHER SOUTH 11.00Z GFS/ECMWF/HIRES ARW. MUCH OF THE CONVECTION
SHOULD PUSH SOUTHEAST OF THE AREA BY 03Z WITH THE PASSAGE OF THE
SHORTWAVE...FOLLOWED BY SIGNIFICANT DRYING OF PRECIPITABLE WATER OF
NEARLY 1 INCH BY 12Z SUNDAY.
ON SUNDAY...THE DEEP UPPER TROUGH OVER SOUTH CENTRAL CANADA IS
PROGGED TO BEGIN ITS DESCENT INTO OUR REGION. A COLD FRONT AHEAD OF
THE TROUGH SHOULD DROP SOUTH THROUGH THE AREA...AGAIN AT THE TIME OF
PEAK HEATING. 0-6KM SHEAR IS RUNNING 40-50 KT WITH 0-3KM AT 25-35KT.
HOWEVER...INSTABILITY LOOKS TO BE SEVERELY LACKING RESULTING FROM THE
SIGNIFICANT DRYING OF PRECIPITABLE WATER SATURDAY NIGHT. 11.00Z GFS
HAS THE GREATEST INSTABILITY AT 500-1000 J/KG OF MLCAPE...BUT THINK
ITS DEWPOINTS IN THE LOW 60S POOLING AROUND THE BOUNDARY ARE TOO
HIGH. FOR NOW HAVE CONTINUED SOME CHANCES OF PRECIPITATION FOR THE
FRONT...BUT BELIEVE THE DRIER 11.00Z ECMWF/CANADIAN/NAM WILL COME
TRUE. MUCH COOLER AND DRIER AIR SINKS SOUTH INTO THE AREA SUNDAY
NIGHT IN THE WAKE OF THE FRONT.
MONDAY AND TUESDAY STILL LOOK LIKE A TASTE OF FALL AS A SHOT OF
MODIFIED ARCTIC AIR COMES INTO THE REGION. AN UPPER LOW WITHIN THE
DEEP UPPER TROUGH IS PROGGED TO SLIDE ACROSS NORTHERN WI MONDAY
EVENING. COOL TEMPERATURES ALOFT...DAYTIME HEATING AND DPVA AHEAD OF
THE UPPER LOW SHOULD PROMOTE SHOWER DEVELOPMENT ACROSS MUCH OF THE
REGION MONDAY. THIS WILL BE ESPECIALLY TRUE OVER NORTHERN WI. HAVE
RAISED PRECIPITATION CHANCES AND FURTHER INCREASES MAY BE NECESSARY.
PRECIPITATION CHANCES CONTINUE INTO TUESDAY AS WELL WITH THE COLD
AIR ALOFT STILL AROUND. 850MB TEMPERATURES PLUMMET TO 4-6C ON MONDAY
ON A BREEZY NORTHWEST WIND AND HOLD THERE THROUGH TUESDAY. THESE ARE
2-2.5 STANDARD DEVIATIONS BELOW NORMAL SUGGESTING RECORDS ARE
POSSIBLE. SEE CLIMATE SECTION BELOW FOR MORE DETAILS.
THE WEATHER QUIETS DOWN THEN FOR WEDNESDAY AND THROUGH THE END OF
THE WEEK AS THE DEEP UPPER TROUGH GRADUALLY EJECTS OUT. PLENTIFUL
DRY CANADIAN AIR PLUNGES SOUTH THROUGH MUCH OF THE EASTERN U.S....
RESULTING IN A DRY FORECAST FOR WEDNESDAY AND BEYOND. TEMPERATURES
WILL GRADUALLY WARM EACH DAY AS THE SUN HELPS MODIFY THE COLD AIR.
WE SHOULD BE BACK CLOSE TO NORMAL BY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 635 AM CDT FRI JUL 11 2014
FORCING REMAINS WEAK ACROSS THE AREA TODAY AND THE BULK OF THE
MOISTURE AT AND ABOVE 850MB. SCT SHRA EXPECTED TO SPREAD ACROSS THE
TAF SITES THIS MORNING INTO EARLY THIS AFTERNOON BUT MOST VSBYS TO
REMAIN 10SM WITH VFR CIGS. GRADIENT TIGHTENS OVER THE AREA TODAY AND
WITH DIURNAL WARMING/MIXING BRISK/GUSTY SOUTH TO SOUTHWEST WINDS
EXPECTED FOR THE LATE MORNING AND AFTERNOON HOURS TODAY.
MOISTURE CONTINUES TO INCREASE TONIGHT BUT SIGNALS FOR SHRA/TSRA
OVER THE AREA QUITE VARIED. MORE OF A SIGNAL FOR CONVECTION TO FIRE
WEST AND SOUTH OF THE TAF SITES TONIGHT SO LEFT VCTS/VCSH MENTIONS
OUT OF THE KRST/KLSE TAFS FOR NOW GIVEN LOW CONFIDENCE IN ANY SHRA/
TSRA IN THE AREA LATER TONIGHT. WITH THE INCREASING MOISTURE AND
APPROACH OF A SFC FRONT/TROUGH AXIS DID INCREASE THE LOWER CLOUDS
TONIGHT. CARRIED SOME MVFR BR AT KRST AND INCLUDED 4K-5K FT CIGS AT
BOTH KRST/KLSE AFTER 06-07Z FOR NOW.
&&
.CLIMATE...
ISSUED AT 255 AM CDT FRI JUL 11 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI
RIVER VALLEY. FORECAST HIGH TEMPERATURES FOR TUESDAY ARE 65 AT
ROCHESTER AND 66 AT LA CROSSE. THESE TEMPERATURES WOULD BREAK THE
RECORD LOWEST HIGH TEMPERATURES FOR JULY 15TH. THE OLD RECORDS ARE
68 AT LA CROSSE SET BACK IN 1962 AND 67 AT ROCHESTER ALSO SET
BACK IN 1962.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
CLIMATE......AJ
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
909 AM PDT FRI JUL 11 2014
.UPDATE...
WE MADE A SMALL ADJUSTMENT TO INCLUDE THE RENO-CARSON VICINITY,
SUSANVILLE AND HAWTHORNE IN THE ISOLATED THUNDERSTORM AREA THIS
AFTERNOON. THIS CHANGE WILL BE MOST NOTABLE FOR THE WEB PAGE SO
THAT THESE CITY CENTERS WILL BE INCLUDED IN THE THUNDERSTORM
THREAT. MOIST AND UNSTABLE CONDITIONS ARE LIKELY TO CONTINUE
THROUGH THIS AFTERNOON WITH THE WEST WINDS LATER TODAY NOT
BRINGING MUCH DRYING. IN ADDITION, THE CAPPING INVERSION BETWEEN
400-450 MB ON THE RENO 12Z SOUNDING WHICH MAY HAVE LIMITED
LIGHTNING ACTIVITY OVERNIGHT IS PROJECTED TO ERODE BY MID
AFTERNOON.
THE 12Z NAM AND EARLY MORNING HRRR RUNS BROUGHT ISOLATED CONVECTION
EVEN FARTHER WEST TO A PORTION OF THE SIERRA ZONES, BUT CONFIDENCE
IS MARGINAL SINCE BETTER LOW LEVEL CONVERGENCE SHOULD BE EAST OF
THE TAHOE BASIN AND NORTHERN MONO COUNTY BY THE TIME WE REACH PEAK
HEATING. MJD
&&
.PREVIOUS DISCUSSION... /ISSUED 620 AM PDT FRI JUL 11 2014/
UPDATE...
UPDATING TO REMOVE THUNDERSTORMS FROM THIS MORNING. INSTABILITY
HAS BEEN WEAK OVERNIGHT WITH ONLY SHOWERS ACROSS NORTHEAST
CALIFORNIA AND NORTHWEST NEVADA. EXPECT THIS TREND TO CONTINUE
THROUGH THE MORNING WITH ONLY SHOWERS. OTHERWISE, NO CHANGES AS
SOLAR HEATING SHOULD RESULT IN ISOLATED SHOWERS AND STORMS THIS
AFTERNOON FOCUSED NORTH OF I-80. WALLMANN
FIRE WEATHER...
WITH INSTABILITY WEAKER THAN EXPECTED OVERNIGHT, ONLY LIGHT
SHOWERS FORMED. LIGHTNING WAS LIMITED TO A FEW ISOLATED STRIKES
WEST OF THE CREST. WITH THIS TREND TO CONTINUE THROUGH THE
MORNING, HAVE CANCELED THE RED FLAG WARNING. ISOLATED
THUNDERSTORMS ARE EXPECTED TO FORM LATER TODAY, BUT WITH THE
MOISTURE IN PLACE EXCEPT THEM TO BE MOSTLY WET. WALLMANN
PREVIOUS DISCUSSION... /ISSUED 311 AM PDT FRI JUL 11 2014/
SYNOPSIS...
ISOLATED TO SCATTERED THUNDERSTORMS FOR THE SIERRA AND WESTERN
NEVADA MAY CONTINUE NORTH OF SUSANVILLE AND GERLACH THIS MORNING.
ANOTHER ROUND OF STORMS IS POSSIBLE FROM NEAR INTERSTATE 80 NORTH
THIS AFTERNOON BEFORE HIGH PRESSURE STRENGTHENS OVER THE WEEKEND
FOR DRIER AND HOTTER CONDITIONS.
SHORT TERM...
EXPANDED COVERAGE OF THUNDERSTORMS SLIGHTLY FURTHER SOUTH FOR THIS
AFTERNOON AND EVENING. NO OTHER MAJOR CHANGES TO THE SHORT TERM
FORECAST.
AS OF 3 AM, WEAK ISOLATED-SCATTERED SHOWERS WERE MOVING NORTHWEST
ACROSS NORTHEASTERN CALIFORNIA AND NORTHWEST NEVADA MAINLY NORTH OF
HIGHWAY 50. WATER VAPOR IMAGERY ALSO SHOWED THE NEGATIVELY-TILTED
TROUGH JUST OFF THE CALIFORNIA COAST AND ITS ASSOCIATED JET
PUSHING INTO NORTHERN CALIFORNIA THIS MORNING. ISOLATED
THUNDERSTORMS AND LIGHTNING HAVE ALREADY BEGUN TO AFFECT AREAS
WEST OF THE CREST NEAR GRASS VALLEY AND REDDING EARLY THIS
MORNING. THUNDERSTORMS ARE EXPECTED TO BECOME MORE WIDESPREAD AS
FORCING/INSTABILITY PUSHES IN WITH THE TROUGH THROUGH THE MORNING.
FORECAST MODELS AND HIGH RESOLUTION FORECASTS (HRRR) STILL
INDICATING THAT THE BEST FORCING WILL FOCUS WEST OF THE SIERRA AND
ACROSS FAR NORTHERN CALIFORNIA AND SOUTHERN OREGON. WITH THE
POTENTIAL FOR ELEVATED CONVECTION ACROSS NORTHEASTERN CALIFORNIA
AND NORTHWEST NEVADA, DRY LIGHTNING AND POSSIBLE FIRE STARTS IS A
CONCERN. CHECK OUT THE FIRE WEATHER DISCUSSION FOR MORE DETAILS.
THE MAIN UPPER FORCING/JET NOSE SLIDES INTO EXTREME NORTHERN
NEVADA AND SOUTHEAST OREGON BETWEEN MID MORNING AND EARLY
AFTERNOON TODAY. WITH THE SLOWER TIMING OF THE INCOMING TROUGH AND
ITS UPPER LEVEL FORCING, WENT AHEAD AND SPREAD THE POTENTIAL FOR
ISOLATED THUNDERSTORMS FURTHER SOUTH FOR THIS AFTERNOON/EVENING.
THUNDERSTORMS WILL LIKELY FORM ALONG THE SIERRA AND THEN BE PUSHED
EASTWARD BY THE ZEPHYR WINDS IN THE AFTERNOON. KEPT THUNDERSTORMS
OUT OF TAHOE AND THE SIERRA FOR THIS REASON. OTHERWISE, INCREASING
SOUTHWEST FLOW ALOFT THROUGH THE DAY WILL GRADUALLY STABILIZE AND
DRY OUT THE ATMOSPHERE BY THE EVENING.
DRIER AND MORE STABLE AIR REALLY INVADES THE EASTERN SIERRA AND
WESTERN NEVADA BY SATURDAY AS THE FOUR CORNERS RIDGE BEGINS TO BUILD
WESTWARD INTO CALIFORNIA AND NEVADA. DAYTIME HIGHS ON SATURDAY WILL
BE NEAR OR SLIGHTLY ABOVE AVERAGE, BUT EXPECT TO SEE A SIGNIFICANT
WARMUP INTO NEXT WEEK. ELW
LONG TERM...MONDAY THROUGH THURSDAY...
HIGH PRESSURE REMAINS OVER NEVADA NEXT WEEK WITH A DAILY THREAT OF
THUNDERSTORMS ALONG WITH ABOVE AVERAGE TEMPERATURES. THE MODELS,
ESPECIALLY THE GFS AND EC, REMAIN IN VERY GOOD AGREEMENT ON THIS.
GFS/EC NOW IN BETTER AGREEMENT WITH SOME MID-LEVEL COOLING WITH MORE
INSTABILITY MONDAY ALONG AND JUST EAST OF THE SIERRA CREST. WITH
MOISTURE STILL IN PLACE FROM THIS WEEK`S EVENT, THUNDERSTORMS ARE
POSSIBLE IN THIS AREA. TEMPERATURES WILL REMAIN HOT AND INTO THE
TRIPLE DIGITS IN WESTERN NEVADA AND 80S TO LOW 90S SIERRA. WITH THIS
BEING THE FIRST THUNDERSTORM DAY, A MIX OF WET AND DRY ARE POSSIBLE
WITH PW AROUND 0.8 INCHES. MONDAY WOULD BE THE BIGGEST CONCERN FOR
FIRE WEATHER.
ON TUESDAY INTO WEDNESDAY, THE HIGH SHIFTS A BIT FURTHER EAST INTO
EASTERN NEVADA WITH MOISTURE STREAMING UP FROM THE MONSOON. EXPECT
COVERAGE OF STORMS TO INCREASE WITH THE BEST DAY FOR STORMS LIKELY
WEDNESDAY. DAYTIME TEMPS WILL LIKELY SEE A COOLING TREND DUE TO
INCREASED CLOUD COVER.
ON THURSDAY, IT APPEARS A WEAK TROUGH WILL BEGIN TO MOVE INTO THE
PACNW CREATING A LIGHT SW FLOW. THIS SHOULD START A DRYING TREND SO
BEGAN TO TREND THE THREAT OF STORMS DOWNWARD. WALLMANN
AVIATION...
ISOLATED THUNDERSTORMS REMAIN POSSIBLE THIS MORNING, MAINLY NORTH OF
LAKE TAHOE INTO LASSEN COUNTY. BKN-OVC CIGS TO REMAIN NEAR 10 KFT.
THIS AFTERNOON, EXPECT MORE SHOWERS AND STORMS TO BE CONCENTRATED
NORTH OF I-80 WITH SFC WND GUSTS TO 40 KTS THE PRIMARY THREAT.
AFTERNOON SW WINDS ALSO LIKELY INTO THE RENO-TAHOE TERMINALS THIS
AFTERNOON WITH PEAK GUSTS 25 KTS 22-03Z. THIS WEEKEND LOOKS DRY WITH
THE NEXT THREAT OF THUNDERSTORMS NEXT WEEK. WALLMANN
FIRE WEATHER...
THIS MORNING, GOOD INSTABILITY ALOFT, STEEP UPPER LEVEL LAPSE RATES,
AND FORCING FROM THE MID AND UPPER-LEVEL WAVE WILL CONTINUE THE
THREAT FOR ELEVATED THUNDERSTORMS. STORMS WILL BE A MIX OF
WET AND DRY, AS PRECIPITABLE WATER INCREASES TO OVER 0.80". BUT AS
THE WAVE PUSHES INLAND, THE MIDLEVEL STEERING FLOW WILL INCREASE TO
OVER 30KTS. THIS INCREASED STORM SPEED WILL ALLOW FOR LESS RAINFALL
OVERALL AND HIGHER POTENTIAL FOR DRY LIGHTNING STRIKES. RED FLAG
WARNING IS IN EFFECT THROUGH 11 AM THIS MORNING FOR AREAS NORTH OF
TAHOE IN NORTHEASTERN CALIFORNIA AND THE NORTHEAST SIERRA. IT
STILL APPEARS THE BRUNT OF THE STORMS WILL REMAIN WEST OF THE
CREST THIS MORNING. SO FAR, LIGHTNING HAS BEEN LIMITED TO AROUND
LAKE OROVILLE. LATEST HRRR SHOWS STORMS TO INCREASE A BIT MORE
AFTER SUNRISE SO WILL LEAVE FORECAST ALONE FOR NOW.
THIS AFTERNOON CONVECTION WILL AGAIN DEVELOP IN NORTHWEST NEVADA
AND NORTHEAST CA. THESE STORMS WILL BE A MIX OF WET AND DRY STORMS
AS WELL, AS MID LEVEL FLOW REMAINS STRONGER.
THE NEXT THREAT FOR THUNDERSTORMS WILL BE MONDAY UNDER THE STRONG
RIDGE AND VERY HOT TEMPERATURES. THAT WILL BE THE BEST DAY FOR DRY
LIGHTNING DUE TO THE VERY HOT TEMPERATURES. BY TUESDAY/WEDNESDAY
MOISTURE WILL INCREASE WITH THE STORMS WET AND LOCALLY HEAVY RAINS
POSSIBLE. HOON/WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1115 AM CDT FRI JUL 11 2014
.DISCUSSION...
259 AM CDT
TODAY...
LARGEST FOCUS FOR THE DAY WILL BE ON THE GRADUAL DEPARTURE TO THE
SFC RIDGE...WHICH GUIDANCE HAS SLOWED SLIGHTLY. THIS SHUD ALLOW FOR
A MOSTLY DRY DAY...HOWEVER AS THE EVENING PROGRESSES AND HIGHER DEW
PTS STEADILY ADVECT NORTH ACROSS THE FORECAST AREA...PRECIP CHANCES
WILL STEADILY INCREASE. AT THIS TIME CONFIDENCE IS HIGH THAT ANY
PRECIP WILL NOW HOLD OFF UNTIL AFT 00Z...SO HAVE PUSHED THE TIMING
BACK A FEW HOURS. THE THERMAL TROUGH THAT HELPED TO KEEP TEMPS DOWN
A FEW DEGREES WILL ALSO DEPART TODAY...HOWEVER CLOUDS WILL BE
STEADILY ON THE INCREASE THROUGHOUT THE AFTERNOON. BUT EXPECT TEMPS
REBOUNDING INTO THE UPR 70S TO LOW 80S. WINDS SHUD BE GENERALLY
SOUTHERLY...THE ONLY EXCEPTION COULD BE FAR NORTHEAST IL WHERE WINDS
MAY BE SLIGHTLY TURNED FROM THE SOUTHEAST AND USHER IN SLIGHTLY
COOLER AIR INTO NORTHEAST LAKE COUNTY.
TONIGHT THROUGH SATURDAY...
AS PREVIOUSLY NOTED...HAVE PUSHED BACK THE TIMING OF THE PRECIP
UNTIL AFT 00Z. SOME WEAK DIFFLUENCE IN THE MID-LVLS IS STILL
PRESENT...ALTHOUGH STEADILY WEAKENING AS THE EVENING PROGRESSES.
WARM/MOIST AIR WILL CONTINUE TO ADVECT NORTH INTO THE FORECAST
AREA...WITH SKIES BECOMING MOSTLY CLOUDY. INSTABILITY AT THE ONSET
IS NOT SIGNIFICANT...SO EXPECT THE LEADING EDGE OF THE PRECIP TO
PERHAPS NOT HAVE MUCH CONVECTION WITH IT. THIS WILL HOWEVER CHANGE
AS THE OVERNIGHT HOURS PROGRESS INTO SAT MORNING. HI-RES LCL ARW8KM
HAS FOR A FEW CYCLES BEEN SUGGESTIVE OF A LOBE OF VORTICITY SLIDING
EAST/SOUTHEAST ACROSS IA/CENTRAL IL AFT 09Z SAT THEN TURNING
SOUTHEAST. PWAT VALUES CONTINUE TO BE PROGGED AT 3 TO 4 SIGMA...OR
HOVERING AT 2" FOR MUCH OF THE FORECAST AREA. SO ANY CONVECTION THAT
DEVELOPS COULD EASILY PRODUCE SOME BRIEF HEAVY DOWNPOURS.
SAT MORNING MAY FEATURE A BRIEF LULL IN THE ACTIVITY...DESPITE THE
HIGH DEW PTS THAT WILL CONTINUE TO ADVECT NORTH/NORTHEAST ACROSS THE
REGION. A FEW SOLUTIONS HAVE CONTINUED TO POINT TOWARDS DEW PTS
NEARING THE MID 70S BY SAT AFTN. SO A VERY HUMID ENVIRONMENT IS IN
SHAPE FOR SAT...FORTUNATELY ABUNDANT CLOUD COVER WILL KEEP TEMPS
FROM GETTING TOO OUT OF CONTROL. THUS HAVE ONLY MADE MINOR
ADJUSTMENTS TO THE AFTN HIGHS...WHICH WILL GENERALLY BE IN THE
LOW/MID 80S.
THE FOCUS FOR ADDTL CONVECTIVE DEVELOPMENT WILL BE ON THE SHORTWAVE
PROGGED TO BE LIFTING INTO THE CENTRAL PLAINS SAT AFTN. THE MAIN
TROUGH AXIS WILL BE STARTING TO DIG INTO THE NORTHERN PLAINS SAT
AFTN/EVE...WHICH WILL AID IN INCREASING THE SOUTHWEST LLVL FLOW SAT
EVE FOR THE FORECAST AREA. THIS COUPLED WITH INCREASING
SHEAR...COULD AID IN THE POTENTIAL FOR STRONG TO PERHAPS SEVERE
STORMS TO DEVELOP SAT EVE. GENERAL STORM MOTION SHOULD BE WEST-EAST.
CONFIDENCE...MEDIUM/HIGH.
SUNDAY THROUGH THURSDAY...
FOCUS FOR THE SECOND HALF OF THE WEEKEND INTO NEXT WEEK WILL BE THE
UNSEASONABLY COOL WEATHER EXPECTED FOR NEXT WEEK. ALTHOUGH PRIOR TO
THE ARRIVAL...SUN WILL FEATURE A COUPLE BOUNDARIES PUSHING EAST
ACROSS THE REGION. A WEAK BOUNDARY SHUD BE ORIENTED FROM NORTHERN MO
STRETCHING NORTHEAST THRU SOUTHERN MI...WITH A SECONDARY WAVE
APPROACHING THE REGION LATE SUN NGT/EARLY MON. THE 500MB VORT WILL
BE ARRIVING OVER THE UPPER MIDWEST LATE SUN...WITH A FEW WEAK LOBES
OF VORTICITY PIVOTING ARND THE AXIS. 850MB THERMAL TROUGH WILL ONLY
CONTINUE TO COOL AS TIME PROGRESSES...AND EXPECT BY TUE TEMPS ALOFT
TO NEAR -3 SIGMA. ENSEMBLES HAVE MAINTAINED A HIGH CONFIDENCE WITH
MINIMAL SPREAD FOR NUMEROUS CYCLES. BASED ON THE PATTERN OF A HIGH
AMPLITUDE RIDGE DEVELOPING ACROSS THE WESTERN CONUS/CANADA...THIS
WILL TRANSLATE INTO A DEEP/STRONG TROUGH FOR THE GREAT LAKES. EXPECT
TEMPS TUE TO STRUGGLE TO WARM BEYOND THE UPR 60S FOR SOME LOCATIONS
NORTH OF I-80...AND PERHAPS ARND 70 ELSEWHERE.
AS THE EXTENDED PERIODS PROGRESS...THE POTENCY OF THE TROUGH BEGINS
TO MODERATE AND TEMPS START TO WARM GENERALLY INTO THE MID 70S WITH
BROAD SFC RIDGING BUILDING IN.
CONFIDENCE...HIGH.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* POTENTIAL FOR A LAKE BREEZE THIS AFTERNOON.
* TSRA LATER TONIGHT WITH MVFR/IFR POSSIBLE.
* MVFR CONDITIONS AFTER TSRA NEAR DAYBREAK SATURDAY.
MDB
//DISCUSSION...UPDATED 16Z...
BAND OF SPRINKLES AND MAYBE A FEW SHOWERS CONTINUES TO MOVE ACROSS
NORTHWEST AND INTO NORTH-CENTRAL ILLINOIS. THIS MAY BRING
SPRINKLES OR A LIGHT SHOWER TO RFD BY MIDDAY BUT THAT MAY BE TOO
PESSIMISTIC. OTHERWISE...WINDS ARE STARTING TO INCREASE IN SPEED
ACROSS NORTH CENTRAL ILLINOIS WITH MORE VARIABILITY ACROSS THE
CHICAGO AREA AND NW INDIANA. STILL APPEARS THE TREND FOR THESE
AREAS WILL BE TO END UP SOUTH-SOUTHEAST WITH A LAKE BREEZE STAYING
EAST OF ORD/MDW...THOUGH GYY MAY SEE MORE OF AN EASTERLY SHIFT
THAN CURRENTLY INDICATED. MID AND HIGH CLOUD COVER WILL CONTINUE
TO INCREASE.
MDB
FROM 12Z...
BENIGN CONDITIONS THIS MORNING ACROSS THE TERMINALS AS HIGH
PRESSURE SHIFTS EAST OF THE AREA RESULTING IN LIGHT SSE WINDS.
WINDS WILL GRADUALLY PICK UP OUT OF THE SOUTH FROM WEST TO EAST AS
THE GRADIENT INCREASES. LAKE BREEZE IS THE FIRST CHALLENGE IN THIS
TAF PACKAGE. CONCERN IS THAT THE GRADIENT WILL NOT BE STRONG
ENOUGH TO PREVENT THE LAKE BREEZE FROM MAKING IT TO MDW AND
POSSIBLY ORD. THERE IS MIXED SIGNALS IN HIGH RESOLUTION
GUIDANCE...AS THE HRRR BRINGS THE LAKE BREEZE THROUGH BOTH ORD AND
MDW...WHILE MOST OTHER GUIDANCE BRINGS IT CLOSE BEFORE LOWER LEVEL
SOUTHERLY WINDS PICK UP. WILL CONTINUE WITH CURRENT THINKING THAT
IT WILL GET TO MDW AND NOT QUITE TO ORD BUT CONFIDENCE ON THIS IS
NOT SUPER HIGH.
ONCE SOUTHERLY WINDS PICK UP AND LIMIT THE LAKE BREEZE...CONCERN
SHIFTS TO THUNDERSTORM ACTIVITY LATER TONIGHT. HAVE GONE WITH
PROB30 TSRA AS CONFIDENCE IS NOT HIGH ON THE TIMING AT THIS POINT
AND IT COULD ACTUALLY BE A LITTLE SOONER THAN IN THE CURRENT
FORECAST. IT LOOKS LIKE SHOWERS WITH EMBEDDED THUNDER AS
INSTABILITY IS NOT ALL THAT HIGH. AFTER THUNDERSTORM ACTIVITY
CLEARS...EXPECT LINGERING LOW LEVEL MOISTURE AND A LIGHT GRADIENT
WILL RESULT IN MVFR CIGS FOR A TIME.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* LOW CONFIDENCE IN LAKE BREEZE REACHING ORD TODAY...LOW TO
MEDIUM CONFIDENCE IN GETTING VERY CLOSE TO MDW.
* MEDIUM CONFIDENCE IN TSRA IMPACTING THE TERMINALS LATE
TONIGHT...BUT LOW CONFIDENCE ON TIMING.
* MEDIUM CONFIDENCE ON MVFR CIGS FOLLOWING TSRA...BUT LOW
CONFIDENCE ON TIMING.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...TSRA WITH MVFR/IFR POSSIBLE.
SUNDAY THROUGH TUESDAY...PERIODIC CHANCES FOR TSRA/SHRA. PRIMARILY VFR.
WEDNESDAY THROUGH THURSDAY...SMALL CHANCES FOR SHRA. PRIMARILY VFR.
KMD
&&
.MARINE...
332 AM CDT
HIGH PRESSURE HAS SHIFTED TO THE EASTERN GREAT LAKES EARLY THIS
MORNING...AND WINDS HAVE TURNED MORE SOUTHERLY ACROSS THE LAKE.
EXPECT SPEEDS TO INCREASE TODAY IN RESPONSE TO A STRONGER GRADIENT
CREATED BY LOW PRESSURE CENTERED IN NORTHERN MANITOBA AND INTO THE
NORTHERN PLAINS. THE STRONGER GRADIENT WILL BE OVER THE NORTHERN
HALF OF THE LAKE...WHERE SOUTH WINDS INCREASE TO 15 TO 25 KT...WHILE
THE SOUTH HALF WILL SEE S TO SE WINDS AT 10-20 KT. WINDS DIMINISH
SATURDAY AS A TROUGH OF LOW PRESSURE MOVES OVERHEAD AND BECOME
SOUTHWEST SATURDAY NIGHT.
A LOW PASSES WELL NORTH OF THE LAKE SATURDAY NIGHT AND SUNDAY AND
ITS COLD FRONT SWINGS OVER THE LAKE SUNDAY MORNING. WINDS BECOME
WEST BEHIND THE FRONT MAINLY FOR THE NORTHERN HALF...AND THEN A
SECOND FRONT PUSHES DOWN THE LAKE SUNDAY NIGHT INTO MONDAY BEFORE
FINALLY CLEARING THE LAKE MONDAY EVENING. WINDS WILL BECOME NORTH
TO NORTHWEST 10-20 KT BEHIND THE FRONT. WINDS DIMINISH LATE TUESDAY
NIGHT AND THEN HIGH PRESSURE MOVES OVER THE LAKE WEDNESDAY NIGHT.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1237 PM CDT FRI JUL 11 2014
.DISCUSSION...
11/18Z TAF ISSUANCE.
&&
.AVIATION...
FEW CU BEGINNING TO DEVELOP ACRS THE AREA...WITH DEEPEST CLOUDS
CONCENTRATED ALONG THE SEABREEZE NR THE COAST. SFC HIGH PRES
CNTRD OHD IS PRODUCING NR CALM OR LT VRBL WINDS...AND PER LATEST
VISBL SATELLITE TRENDS...THE SEABREEZE TRANSITIONS TO LAND BREEZE
S OF VERMILION BAY DUE A BETTER OFFSHORE WIND COMPONENT. A FEW
SMALL ISOLTD SH OR TS HAVE DEVELOPED ALONG THE BOUNDARY...WITH
LITTLE ELSEWHERE AS WEAK MID LVL RIDGING HELPS LIMIT CONVECTION.
REMOVED TEMPO GROUPS FM SRN SITES BUT KEPT VCTS AS SOME INLAND
PROGRESSION OF SEABREEZE STILL ANTICIPATED DURING THE AFTN.
OTHERWISE...VFR EXPECTED TO PREVAIL THROUGH THE PERIOD. 24
&&
.PREV DISCUSSION... /ISSUED 1039 AM CDT FRI JUL 11 2014/
UPDATE...
VISIBLE SATELLITE IMAGERY SHOWING CLOUDS BOILING UP ALONG THE
COASTLINE PRETTY MUCH OUTLINING THE SEA BREEZE RIGHT ALONG THE
COAST. CLOUD BUILDUP INITIALLY LOOKED BETTER NEAR SABINE LAKE
AREA...THEN POOF...GONE...TO STABLE THERE STILL. THERE IS ALSO
BUILDUP FROM EAST OF GRAND CHENIER EXTENDING EAST TO PECAN
ISLAND. RADAR ALSO SHOWING THE INITIAL BUDDINGS OF SHOWERS
DEVELOPING EAST OF PECAN ISLAND. ONE THING TO NOTE TODAY...THE UPPER
LEVEL STEERING CURRENTS LOOK VERY WEAK. THEREFORE...EXPECT
CONVECTION TO HOLD PRETTY TIGHT TO THE SEA BREEZE. OUTFLOW
BOUNDARIES WILL NEED TO BE EXCEPTIONAL TODAY TO GET BETTER
DISTRIBUTION. MY INITIAL THOUGHTS...ZONE FORECAST PACKAGE LOOKS
PRETTY GOOD. I WILL NOT MAKE ANY CHANGES TO THE CURRENT PACKAGE. I
DO SEE THAT THIS EVENING... HIGH RESOLUTION RAPID REFRESH MODEL
(HRRR) AND WEATHER RESEARCH AND FORECAST MODEL (WRF) ARE SHOWING
SOME CARRYOVER INTO THE EVENING PACKAGE FOR SOME RAIN TO CONTINUE
IN SOME AREAS MOSTLY BETWEEN THE I-10 CORRIDOR BETWEEN LAKE
CHARLES AND LAFAYETTE. WILL MONITOR AND MAKE CHANGES LATER TO
EVENING ZONES IF THIS TREND CONTINUES IN THE HRRR AND WRF MODELS.
DID I SAY IT WAS GOING TO BE HOT AND HUMID TODAY? WELL...DRINK
PLENTY OF FLUID IF YOUR GOING TO BE OUTSIDE. YOU ARE GOING TO NEED
GOOD RE-HYDRATION IF OUT TODAY. :)
PREV DISCUSSION... /ISSUED 508 AM CDT FRI JUL 11 2014/
AVIATION...
WEAK HIGH PRESSURE ACROSS CENTRAL LOUISIANA WILL PERMIT THE RETURN
OF THE SEA BREEZE ACROSS THE FORECAST AREA. PERSISTENCE BRINGS
THE SEA BREEZE ONSHORE BY MID-MORNING...BEFORE REACHING THE LAKES
REGION AND PINEY HILLS REGION BY LATE AFTERNOON.
LIFT ATTENDING UPPER LEVEL DIVERGENCE (AN ANTICYCLONIC SHEAR ZONE
ALOFT) WILL GIVE AN ADDED BOOST TO THE FRONTAL LIFT ATTENDING THE
SEA BREEZE.
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED...TAPERING OFF WITH
PASSAGE OF SEA BREEZE.
JT
PREV DISCUSSION... /ISSUED 352 AM CDT FRI JUL 11 2014/
DISCUSSION...RADAR CURRENTLY SHOWING JUST A FEW SHOWERS AND
THUNDERSTORMS OVER THE NEAR COASTAL WATERS. SATELLITE DEPICTING
CLEAR SKIES INLAND. OBS BEGINNING TO PICK UP ON SOME LIGHT FOG
DEVELOPMENT HERE AND THERE WHICH HAS BEEN THE CASE THE LAST SEVERAL
NIGHTS.
TODAY AND THE WEEKEND...WITH A WEAKNESS REMAINING ALOFT...AND LOW
LEVEL SOUTHERLIES MAINTAINING ADEQUATE MOISTURE OVER THE FORECAST AREA...
WILL CONTINUE TO SEE DAILY SHOWER AND THUNDERSTORM DEVELOPMENT.
TRIGGER FOR THIS DEVELOPMENT WILL COME FROM A WEAK SEA BREEZE AND
ACCOMPANYING CONVERGENCE SLOWLY ADVANCING NORTHWARD....AS WELL AS
CONVECTIVE OUTFLOWS. OTHERWISE EXPECT A CONTINUATION OF NEAR NORMAL
TEMPERATURES...GENERALLY SPELLING SOMEWHAT HOT AND HUMID
DAYS...AND WARM AND MUGGY NIGHTS.
REMAINDER OF FORECAST...INTENSE CYCLONE PROGGED SIMILARLY BY
MODELS TO DROP OUT OF MID-CANADA AND INTO GREAT LAKES REGION EARLY
IN THE NEW-WEEK. THIS UNLIKELY MID-JULY FEATURE WILL BE
RESPONSIBLE FOR ADVANCING A COOL FRONT INTO THE AREA
TUESDAY...POSSIBLY PUNCHING FEATURE AS FAR SOUTH AS THE NORTHERN GULF
WATERS BEFORE WASHING OUT. SCENARIO PROMPTED AN INCREASE IN POPS
FOR TUESDAY AND TUESDAY NIGHT. SOUTHERN PORTION OF COLD DOME
GLANCING THE AREA WILL BRING NO MORE THAN A SLIGHT DECREASE IN
TEMPS AND DEWPOINTS. MUCH MORE IMPRESSIVE LOWERING OF THESE
ELEMENTS WILL OCCUR FURTHER NORTH AND LIKELY WILL BE RECORD-
BREAKING. RAIN CHANCES THEN CONTINUE THROUGH THE REST OF THE
FORECAST AS STRONG SOUTHERLIES DEVELOP AND IMPULSES APPROACH
AND MOVE OVERHEAD WITHIN A RELATIVELY STRONG JULY NORTHWEST FLOW
ALOFT.
MARINE...WEAK HIGH PRESSURE WILL CONTINUE TO HOLD OVER THE GULF
WATERS MAINTAINING LIGHT WINDS AND LOWS SEAS. ISOLATED SHOWER AND
THUNDERSTORM ACTIVITY WILL GENERALLY BE THROUGH THE NIGHT-TIME
HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 93 75 93 75 / 30 10 30 10
KBPT 92 76 92 76 / 30 20 30 10
KAEX 94 75 93 75 / 20 10 20 10
KLFT 93 76 93 76 / 30 20 30 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
432 PM EDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 429 PM EDT FRI JUL 11 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A ZONAL PATTERN THROUGH THE
NRN CONUS BETWEEN A TROUGH OVER CNTRL CANADA AND A RIDGE OVER THE
SRN PLAINS. A WEAK SHORTWAVE TROUGH OVER LAKE SUPERIOR INTO CNTRL
UPPER MI HELPED PRODUCE SOME LIGHT SHOWERS ACROSS THE CWA TODAY.
SCT/ISOLD SHRA/TSRA FROM NEAR KINL INTO N CNTRL MN HAD DEVELOPED
ALONG A COLD FRONT/TROUGH AHEAD OF ANOTHER WEAK SHRTWV MOVING
THROUGH NORTH DAKOTA. MOSTLY CLOUDY SKIES OVER UPPER MI HAD LIMITED
TEMPS TO THE LOWER TO MID 70S AND LIMITED MLCAPE VALUES TO LESS THAN
400 J/KG.
TONIGHT...EXPECT THAT SHRA/TSRA OVER NRN MN WILL EXPAND IN COVERAGE
AND MOVE TOWARD UPPER MI. HOWEVER...WITH ONLY MARGINAL INSTABILITY
FCST OVER THE AREA...MUCAPE INTO THE 400-800 J/KG RANGE...THE
CONVECTION SHOULD WEAKEN WITH ONLY ISOLD TSRA. SCT SHRA COVERAGE
WITH CHANCE POPS WAS MENTIONED GIVEN THE WEAK FORCING ASSOCIATED
WITH THE FRONT AND SHRTWV SLIDING THROUGH THE NRN GREAT LAKES. THE
REMAINING SHOWERS ARE EXPECTED TO MOVE INTO THE ERN CWA LATE THIS
EVENING AND DIMINISH FROM WEST TO EAST OVERNIGHT.
SATURDAY...THE WEAKENING COLD FRONT THROUGH UPPER MI WILL PROVIDE A
BOUNDARY/FOCUS FOR POTENTIAL SHRA/TSRA DEVELOPMENT...ESPECIALLY WITH
ONSET OF STRONGER DAYTIME HEATING. EXPECT THE GREATEST PCPN COVERAGE
OVER THE SOUTH AND THROUGH ERN UPPER MI WHERE THE HIGHER RES MODELS
SUGGEST THE LOW LEVEL CONV WILL BE STRONGEST. MLCAPE VALUES TO NEAR
1K J/KG...PER GEM-REGIONAL AND GFS COMBINED WITH 0-6KM SHEAR VALUES
OF 35-40 KNOTS COULD SUPPORT SOME STRONG AND POSSIBLY SEVERE STORMS
IF CLOUD DEPENDENT INSTABILITY IS REALIZED. THE MODELS HAVE ALSO SHOWN A
CONSISTENT SIGNAL THAT SHRA/TSRA WILL MOVE INTO WI ASSOCIATED WITH
STRONGER SHORTWAVE TROUGH. THERE IS STILL TIMING/POSITION UNCERTAINTY
ON HOW IT WOULD AFFECT MAINLY SRN UPPER MI BY LATE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 431 PM EDT FRI JUL 11 2014
THE MAIN STORY IN THE LONG TERM CONTINUES TO BE THE SEPTEMBER-LIKE
CONDITIONS EXPECTED ACROSS THE UPPER GREAT LAKES EARLY NEXT WEEK.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...A DEEP MID-LEVEL LOW OVER FAR
SOUTHWEST HUDSON BAY WILL CONTINUE ITS TREK SOUTHWARD AT THE
BEGINNING OF THE PERIOD. CONVECTIVE POTENTIAL ACROSS THE SOUTHEAST
HALF FOR SATURDAY NIGHT WILL DEPEND HEAVILY ON BOTH THE AMOUNT OF
DIURNAL HEATING SATURDAY AND THE LOCATION OF THE DECAYING LOW-LEVEL
CONVERGENCE ZONE. WHILE MCS ACTIVITY LOOKS TO BE MOST PRONOUNCED
ALONG THE NOSE OF A DEVELOPING LOW-LEVEL JET ACROSS WI SATURDAY
AFTERNOON AND EVENING...RESIDUAL 305-315K ISENTROPIC LIFT NORTH OF
THE LOW-LEVEL BOUNDARY MAY BE ENOUGH TO TAP INTO REMAINING MUCAPE OF
AROUND 500 J/KG AS NOTED BY BOTH THE 12Z NAM AND 12Z GEM. ANY
THUNDER ACTIVITY SHOULD REMAIN WEAK THIS FAR NORTH GIVEN A STABLE
SFC LAYER AND OVERALL LIMITED INSTABILITY. HOWEVER...A FEW STRONGER
GUSTS CANNOT BE RULED OUT IN THE EARLY EVENING HOURS FAR SOUTH
CENTRAL WITH ANY STORM ROOTED ALONG THE SFC CONVERGENCE ZONE.
A MID-LEVEL TROUGH AXIS ASSOCIATED WITH THE DEEP LOW WILL CROSS THE
CWA FROM WEST TO EAST LATE SATURDAY NIGHT INTO SUNDAY. WITH LITTLE
ADDITIONAL SUPPORT AND GENERALLY DRY CONDITIONS...ONLY SOME ISOLATED
SHOWER ACTIVITY IS EXPECTED. AFTER THE TROUGH PASSAGE ON
SUNDAY...SKIES LOOK TO BECOME MOSTLY CLEAR FOR A 12-18 HOUR WINDOW.
THIS WILL ALLOW FOR INCREASED MIXING ACROSS THE WEST...WITH WESTERLY
GUSTS TO 25 MPH ACROSS THE KEWEENAW.
MONDAY AND TUESDAY...BY MONDAY MORNING...THE MID-LEVEL LOW WILL
SPLIT INTO TWO WAVES OVER ONTARIO. THE EASTERN SEGMENT OVER
SOUTHERN JAMES BAY WILL EJECT NORTHEASTWARD ACROSS QUEBEC THROUGH
MONDAY. MEANWHILE...THE WESTERN SEGMENT WILL BE TRACKING
SOUTHEASTWARD ACROSS THE BOUNDARY WATERS OF MN AROUND 12Z MONDAY.
THIS WESTERN EXTENSION WILL BECOME STACKED UPWARD FROM H7...SO
PROGRESSION OF THE SYSTEM WILL BE QUITE SLOW. THE MID/UPPER-LOW IS
PROGGED TO TRACK FROM NEAR DLH MONDAY AFTERNOON TO NEAR GRB BY
TUESDAY AFTERNOON. GIVEN THE OVERALL DYNAMICS OF THE SYSTEM...THE
ENTIRE AREA SHOULD SEE AT LEAST SOME SHOWERS DURING THE DAY. ONE
LIMITING FACTOR TO COVERAGE IS A PRESENCE OF DEEP MOISTURE. SOMEWHAT
DRY AIR ABOVE H5 SHOULD KEEP SHOWERS LESS WIDESPREAD AWAY FROM THE
LOW CENTER. SOME DIURNAL HEATING ASSISTANCE WILL ALSO ALLOW FOR
GREATER COVERAGE AWAY FROM THE GREAT LAKES. THEREFORE...THE BEST
COVERAGE IS EXPECTED ALONG THE WI BORDER...WHERE LIKELY POPS HAVE
BEEN INTRODUCED.
TEMPS WILL BE QUITE COOL FOR MID-JULY...WITH H8 TEMPS AT OR BELOW
5C. WITH CLOUDY AND SHOWERS AROUND...HIGHS WILL STRUGGLE TO GET OUT
OF THE 50S ACROSS MUCH OF THE CWA BOTH MONDAY AND TUESDAY. SOME
LOCALES ALONG LAKE SUPERIOR MAY EVEN FAIL TO REACH 50. THESE NUMBERS
ARE 25 DEGREES BELOW AVERAGE...AND WILL LIKELY SET RECORD LOW
MAXIMUM TEMPS ACROSS THE AREA.
SHOWERY ACTIVITY WILL CONTINUE INTO TUESDAY WITH THE PASSAGE OF A
DEFORMATION/FGEN REGION ON THE BACKSIDE OF THE MID/UPPER LOW. THESE
SHOWERS WILL BE SLOW TO MOVE EASTWARD AS THE LOW ONLY REACHES
NORTHERN LAKE HURON BY LATE TUESDAY NIGHT.
WEDNESDAY THROUGH FRIDAY...THE GFS ADVERTISES A MUCH QUICKER
DEPARTURE OF THE MID-LEVEL LOW THAN THE ECMWF/GEM. THIS HAS
IMPLICATIONS ON THE AMOUNT OF MOISTURE AVAILABLE FOR CONTINUED CLOUD
COVER AND HIGH TEMPS ACROSS THE AREA. OTHERWISE...THE STOUT RIDGE
ACROSS THE WESTERN STATES AND PROVINCES THAT DEVELOPED IN RESPONSE
TO THE DEEP EASTERN TROUGH WILL BEGIN TO SHIFT ACROSS THE NORTHERN
PLAINS ON THURSDAY AND THE UPPER GREAT LAKES ON FRIDAY. THIS SHOULD
BRING AN OVERALL QUIET PERIOD OF WEATHER WITH A GRADUAL WARMING
TREND INTO THE WEEKEND. TEMPS LOOK TO BE BACK TO JUST BELOW AVERAGE
BY FRIDAY. HOWEVER...A FEW DIURNAL INLAND SHOWERS COULD BE POSSIBLE
WITH RETURN MOISTURE THURSDAY AFTERNOON.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 152 PM EDT FRI JUL 11 2014
A BAND OF LIGHT SHOWERS MOVING THROUGH UPPER MICHIGAN THROUGH EARLY
AFTERNOON IS NOT EXPECTED TO BE HEAVY ENOUGH...PER RADAR TRENDS...TO
REDUCE CONDITIONS TO MVFR. THE NEXT SHOT OF SOME SHRA AND POSSIBLE
TSRA IS EXPECTED THIS EVENING AS A WEAK COLD FRONT APPROACHES FROM
MN. LOCATION AND COVERAGE OF ANY PCPN IS QUITE UNCERTAIN...SO ONLY A
VCNTY SHRA MENTION WAS INCLUDED FOR NOW. LIKE TODAY...CONDITIONS
SHOULD STAY MAINLY VFR INTO SATURDAY MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT FRI JUL 11 2014
SOUTH WINDS OF UP TO 20 KTS...POSSIBLY 25 KTS AT HIGHER PLATFORMS
ABOVE MARINE LAYER...EXPECTED INTO THIS EVENING WILL DIMINISH
OVERNIGHT WITH WINDS SHIFTING TO SW. AS SCT SHOWERS ASSOCIATED WITH A
WEAK COLD FRONT OR TROUGH MOVE THROUGH LAKE SUPERIOR...FOG WILL BE
POSSIBLE ACROSS THE ENTIRE LAKE WITH THE TROUGH PASSAGE. LIGHT WINDS
WILL CONTINUE THROUGH SUNDAY BEFORE ANOTHER TROUGH PASSES
SOUTHEASTWARD ACROSS LAKE SUPERIOR SUNDAY NIGHT. GUSTY NORTHWEST
WINDS TO 20 KNOTS EXPECTED BEHIND THIS TROUGH EARLY NEXT WEEK AS HIGH
PRESSURE BUILDS OVER THE NORTHERN PLAINS. &&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KLUBER
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
431 PM EDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 429 PM EDT FRI JUL 11 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A ZONAL PATTERN THROUGH THE
NRN CONUS BETWEEN A TROUGH OVER CNTRL CANADA AND A RIDGE OVER THE
SRN PLAINS. A WEAK SHORTWAVE TROUGH OVER LAKE SUPERIOR INTO CNTRL
UPPER MI HELPED PRODUCE SOME LIGHT SHOWERS ACROSS THE CWA TODAY.
SCT/ISOLD SHRA/TSRA FROM NEAR KINL INTO N CNTRL MN HAD DEVELOPED
ALONG A COLD FRONT/TROUGH AHEAD OF ANOTHER WEAK SHRTWV MOVING
THROUGH NORTH DAKOTA. MOSTLY CLOUDY SKIES OVER UPPER MI HAD LIMITED
TEMPS TO THE LOWER TO MID 70S AND LIMITED MLCAPE VALUES TO LESS THAN
400 J/KG.
TONIGHT...EXPECT THAT SHRA/TSRA OVER NRN MN WILL EXPAND IN COVERAGE
AND MOVE TOWARD UPPER MI. HOWEVER...WITH ONLY MARGINAL INSTABILITY
FCST OVER THE AREA...MUCAPE INTO THE 400-800 J/KG RANGE...THE
CONVECTION SHOULD WEAKEN WITH ONLY ISOLD TSRA. SCT SHRA COVERAGE
WITH CHANCE POPS WAS MENTIONED GIVEN THE WEAK FORCING ASSOCIATED
WITH THE FRONT AND SHRTWV SLIDING THROUGH THE NRN GREAT LAKES. THE
REMAINING SHOWERS ARE EXPECTED TO MOVE INTO THE ERN CWA LATE THIS
EVENING AND DIMINISH FROM WEST TO EAST OVERNIGHT.
SATURDAY...THE WEAKENING COLD FRONT THROUGH UPPER MI WILL PROVIDE A
BOUNDARY/FOCUS FOR POTENTIAL SHRA/TSRA DEVELOPMENT...ESPECIALLY WITH
ONSET OF STRONGER DAYTIME HEATING. EXPECT THE GREATEST PCPN COVERAGE
OVER THE SOUTH AND THROUGH ERN UPPER MI WHERE THE HIGHER RES MODELS
SUGGEST THE LOW LEVEL CONV WILL BE STRONGEST. MLCAPE VALUES TO NEAR
1K J/KG...PER GEM-REGIONAL AND GFS COMBINED WITH 0-6KM SHEAR VALUES
OF 35-40 KNOTS COULD SUPPORT SOME STRONG AND POSSIBLY SEVERE STORMS
IF CLOUD DEPENDENT INSTABILITY IS REALIZED. THE MODELS HAVE ALSO SHOWN A
CONSISTENT SIGNAL THAT SHRA/TSRA WILL MOVE INTO WI ASSOCIATED WITH
STRONGER SHORTWAVE TROUGH. THERE IS STILL TIMING/POSITION UNCERTAINTY
ON HOW IT WOULD AFFECT MAINLY SRN UPPER MI BY LATE AFTERNOON.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 418 AM EDT FRI JUL 11 2014
UNCERTAINTY STILL EXISTS FOR THE WEEKEND AS SUBTLE SHORTWAVES AND
CONVECTIVE COMPLEXES MAKE FORECASTING DIFFICULT.
FOR SAT...THE LOW PRESSURE SYSTEM OVER CENTRAL CANADA WILL REMAIN
STATIONARY AS A WEAK COLD FRONT MOVES INTO THE CWA. THE FRONT WILL
BE OVER NWRN UPPER MI AT 12Z SAT AND LOOKS TO WASH OUT AS IT MOVE
FARTHER INTO UPPER MI. THINK THERE COULD BE SCATTERED SHOWERS AND
THUNDERSTORMS ALONG THE FRONT OVER NWRN UPPER MI. AM MORE UNCERTAIN
WITH CONVECTIVE CHANCES OVER CENTRAL/ERN UPPER MI AS MODELS SHOW A
CONVECTIVE COMPLEX MOVING S OF THE CWA SOMETIME LATE SAT AFTERNOON
INTO EARLY SAT NIGHT. THE NAM IS THE FARTHEST N WITH SHOWING THE
COMPLEX SKIRTING THE SERN CWA. WHILE THIS CANNOT BE COMPLETELY RULED
OUT...WENT MORE WITH THE CONSENSUS APPROACH IN KEEPING THE COMPLEX
FARTHER S. DEPENDING ON THE STRENGTH/TRACK/TIMING OF THE COMPLEX /IF
IT FORMS/...CONVECTION MAY OR MAY NOT DEVELOP FARTHER N OVER THE
CENTRAL AND ERN CWA. IF CONVECTION TO THE S IS MORE
MINIMAL...CONVECTION MAY BE ABLE TO STRENGTHEN OVER THE SCENTRAL CWA
WHERE CAPE VALUES MAY EVEN RISE TO NEAR 1000J/KG WITH DEEP LAYER
SHEAR AROUND 40KTS.
A STRONGER COLD FRONT MOVES THROUGH ON SUN...WITH MODEL VARIABILITY
WITH THE TIMING OF THAT FRONT...ALTHOUGH THE MAJORITY OF MODELS HAVE
IT PASSING THROUGH MUCH OF THE AREA IN THE MORNING TO EARLY
AFTERNOON. THIS DOES NOT ALLOW MUCH TIME FOR INSTABILITY TO DEVELOP.
THINK THAT SCATTERED SHOWERS WILL DEVELOP ALONG THE FRONT OVER
MAINLY ERN UPPER MI...WHERE AT LEAST SOME HEATING WILL OCCUR BEFORE
THE FRONT...AND A WEAK SHORTWAVE RIDING ALONG THAT FRONT...PASSES
THROUGH. PRECIP CHANCES PUSH S THROUGH THE DAY ALONG WITH THE FRONT.
BY 12Z MON...THE UPPER LOW THAT WAS OVER CENTRAL CANADA WILL BE NEAR
INL. THE LOW WILL THEN SHIFT SE AND ACROSS THE GENERAL AREA INTO
TUE...AND SHOULD BE E OF THE CWA BY WED AT THE LATEST...WITH THE GFS
MOVING IT OUT FAR FASTER THAN THE ECMWF AND GEM-NH. AS THAT UPPER
LOW MOVES IN ON MON...THE COLD CORE BEING OVERHEAD OR NEARBY
COMBINED WITH THE HEIGHT FALLS AND DYNAMICS OF THE SYSTEM WILL LEAD
TO SCATTERED SHOWERS OVER MUCH OF THE AREA ON MON INTO TUE.
WITH HOW ANOMALOUSLY STRONG THE LOW WILL BE...THE BIG STORY IN THE
LONG TERM IS TEMPERATURES. 850MB TEMPS WILL BE COLDEST ON TUE AT
4-5C...RESULTING IN HIGH TEMPERATURES IN THE LOW 50S /OR POSSIBLE
NOT EVEN REACHING 50/ OVER NRN UPPER MI...WITH HIGHS IN THE LOW 60S
OVER SCENTRAL UPPER MI. RECORD LOW HIGH TEMPS FOR TUE AT NWS
MARQUETTE IS DEGREES...WHICH QUITE LIKELY WILL BE WARMER THAN WHAT
WE SEE ON TUE. IN FACT THE COLDEST HIGH TEMP FOR THE MONTH OF JULY
IS 51...AND THAT IS NOT EVEN OUT OF THE REALM OF POSSIBILITIES TO
TIE OR BREAK. ALTHOUGH TEMPS DO WARM WED AND THU...THEY SHOULD
CONTINUE TO BE BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 152 PM EDT FRI JUL 11 2014
A BAND OF LIGHT SHOWERS MOVING THROUGH UPPER MICHIGAN THROUGH EARLY
AFTERNOON IS NOT EXPECTED TO BE HEAVY ENOUGH...PER RADAR TRENDS...TO
REDUCE CONDITIONS TO MVFR. THE NEXT SHOT OF SOME SHRA AND POSSIBLE
TSRA IS EXPECTED THIS EVENING AS A WEAK COLD FRONT APPROACHES FROM
MN. LOCATION AND COVERAGE OF ANY PCPN IS QUITE UNCERTAIN...SO ONLY A
VCNTY SHRA MENTION WAS INCLUDED FOR NOW. LIKE TODAY...CONDITIONS
SHOULD STAY MAINLY VFR INTO SATURDAY MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT FRI JUL 11 2014
SOUTH WINDS OF UP TO 20 KTS...POSSIBLY 25 KTS AT HIGHER PLATFORMS
ABOVE MARINE LAYER... EXPECTED INTO THIS EVENING WILL DIMINISH
OVERNIGHT WITH WINDS SHIFTING TO SW. AS SCT SHOWERS ASSOCIATED WITH A
WEAK COLD FRONT OR TROUGH MOVE THROUGH LAKE SUPERIOR...FOG WILL BE
POSSIBLE ACROSS THE ENTIRE LAKE WITH THE TROUGH PASSAGE. LIGHT WINDS
WILL CONTINUE THROUGH SUNDAY BEFORE ANOTHER TROUGH PASSES
SOUTHEASTWARD ACROSS LAKE SUPERIOR SUNDAY NIGHT. GUSTY NORTHWEST
WINDS TO 20 KNOTS EXPECTED BEHIND THIS TROUGH EARLY NEXT WEEK AS
HIGH PRESSURE BUILDS OVER THE NORTHERN PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
241 PM CDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 241 PM CDT FRI JUL 11 2014
LATEST VISIBLE IMAGERY SHOWS AN AREA OF EXTENSIVE LOW CLOUDS NEAR
AND DOWNWIND OF THE SURFACE FRONT/TROUGH AXIS WITH A MORE HEALTHY CU
FIELD TRYING TO DEVELOP NEAR ITS BACK EDGE AND POINTS UPSTREAM.
CLOUDS HAVE MANAGED TO BREAK UP SOUTHEAST OF THERE... INCLUDING THE
SOUTHERN AND EASTERN PORTION OF THE TWIN CITIES... IN THE WAKE OF
THIS MORNING/S CONVECTION. INSTABILITY HAS INCREASE ACROSS THE
WESTERN CWFA... WITH MLCAPE VALUES AOA 500 J/KG WITH NEAR 1500 J/KG
OVER THE FAR WEST. A SUBTLE SHORTWAVE FEATURE CAN BE SEEN IN THE
WATER VAPOR IMAGERY MOVING EAST THROUGH THE ZONAL FLOW ACROSS NORTH
DAKOTA AT THE CURRENT TIME. THIS COULD WORK WITH THE WEAK
CONVERGENCE PRESENT NEAR THE SURFACE TROUGH TO GENERATE SOME
ISOLATED/SCATTERED SHRA/TSRA LATE THIS AFTERNOON INTO EARLY THIS
EVENING. THE NAM IS NOT PARTICULARLY OPTIMISTIC ABOUT ANYTHING OVER
OUR AREA... WHILE THE GFS AND ECMWF MANAGE TO SHOW SOME LIGHT PCPN.
THE CAMS ARE A MIXED BAG... WITH MANY SUCH AS THE HRRR AND A COUPLE
HOPWRF MEMBERS KEEPING THINGS GENERALLY DRY... WHILE A COUPLE HOPWRF
MEMBERS AND THE HIRES WINDOW RUNS MANAGE TO SHOW A FEW CONVECTIVE
CELLS. ALLOWED FOR CHANCE POPS OVER THE AREA FROM LATE AFTERNOON
INTO EVENING TO ACCOUNT FOR THE POSSIBILITY OF A FEW SHRA/TSRA
GETTING GOING. OTHERWISE... THE MAIN LARGE SCALE SUPPORT FOR PCPN
THROUGH TOMORROW LOOKS TO SHIFT TO THE SOUTHERN PORTION OF THE AREA
AND EVEN MORE SO PERHAPS INTO IOWA WHERE THE BAROCLINIC ZONE LOOKS
TO STALL OUT AND THE BEST FRONTOGENESIS AND THETA-E ADVECTION IS
EXPECTED. ALLOWED FOR SOME OF THIS TO SPREAD NORTH DURING THE DAY ON
SATURDAY AS THE FLOW STARTS TO AMPLIFY AND WE SEE A SOMEWHAT
HEALTHIER SHORTWAVE ARRIVE FROM THE WEST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 241 PM CDT FRI JUL 11 2014
THE LONG TERM PORTION OF THE FORECAST WILL BE GREATLY INFLUENCED BY
A HIGHLY AMPLIFIED LARGE SCALE PATTERN...WITH A DEEP TROUGH
DOMINATING EASTERN CANADA/CONUS...AND RIDGING PREVAILING OVER THE
WEST. SAID PATTERN WILL TRANSLATE TO BELOW NORMAL TEMPERATURES FOR
THE EASTERN TWO-THIRDS OF THE CONUS THROUGH MUCH OF NEXT WEEK.
SATURDAY EVENING SHOULD BRING THE EXIT OF ANY LINGERING SHOWERS
AND THUNDERSTORMS...WITH SKIES CLEARING OUT BY SUNDAY.
THUNDERSTORMS LOOK A BIT LESS LIKELY FOR SUNDAY PER THE 12Z MODEL
RUNS...WITH THE ONLY SLIM POTENTIAL APPEARING TO BE OVER FAR
SOUTHERN MN WHERE DIURNALLY-INDUCED ACTIVITY COULD DEVELOP IN THE
WANING BAROCLINIC ZONE.
MONDAY BRINGS THE ARRIVAL OF THE UPPER LOW OVERHEAD...MADE EVIDENT
BY SCATTERED SHOWERS AND TEMPERATURES NEARING 20 DEGREES BELOW
NORMAL. HIGHS IN THE LOW/MID 60S WILL COMBINE WITH BREEZY NORTHWEST
WINDS TO MAKE FOR A CHILLY DAY.
TUESDAY THE TROUGH CENTER WILL HAVE SHIFTED EAST OF THE AREA...SO
SHOWER CHANCES WILL BE MAINLY CONFINED TO WEST CENTRAL WI
COUNTIES. HIGHS WILL MODERATE A TAD...BUT WILL LIKELY STILL TOP
OUT IN THE MID/UPPER 60S.
WEDNESDAY AND THURSDAY THE LOW LIFTS INTO QUEBEC AND HEIGHTS RISE
A BIT. THIS WILL MEAN GRADUALLY MODERATING TEMPERATURES AND DRY
WEATHER...WITH HIGHS IN THE LOW/MID 70S ON WEDNESDAY...AND
MID/UPPER 70S FOR THURSDAY.
BY FRIDAY THE FLOW TRANSITIONS TO NEARLY ZONAL ACROSS THE
CONUS...AS WEAK MID LEVEL TROUGHING OVER SOUTHERN
SASKATCHEWAN/MANITOBA INDUCES HIGH PLAINS SURFACE CYCLOGENESIS.
SOUTHERLY FLOW AHEAD OF THIS FEATURE WILL AID IN FURTHER TEMPERATURE
MODERATION ON FRIDAY...WITH HIGHS IN THE UPPER 70S AND LOWER 80S.
STILL LOOKS TO BE DRY ON FRIDAY...ALTHOUGH THE AFOREMENTIONED
TROUGH SHOULD FACILITATE SHOWER AND THUNDERSTORM CHANCES AT SOME
POINT NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 156 PM CDT FRI JUL 11 2014
WILL HAVE VARIOUS ISSUES THROUGH THE PERIOD. LINGERING CEILINGS
ACROSS THE AREA SHOULD GENERALLY IMPROVE THROUGH THE AFTERNOON...
WHILE REMAINING MOST FOCUS NEAR AND DOWNSTREAM OF THE FRONT/TROUGH
WHERE SOME MVFR REMAINS. THERE IS A CHANCE FOR A FEW SHRA/TSRA
FROM 21Z THROUGH 03Z AT MOST SITES... BUT COVERAGE IS EXPECTED TO
BE LOW IF THINGS OCCUR... SO LEFT ANY MENTION OUT OF THE FORECAST
FOR NOW. LATER TONIGHT WE COULD SEE SOME FOG AT MOST SITES... AND
IT COULD BE WORSE THAN FORECAST IF WINDS DIE AND WE HAVE LESS IN
THE WAY OF MID-HIGH CLOUDS THAN EXPECTED. HINTED AT SOME LOWER
VISIBILITIES... BUT DID NOT GO AS LOW AS WHAT IS POSSIBLE GIVEN
THE UNCERTAINTY. SHRA/TSRA WILL BE POSSIBLE AGAIN ON SATURDAY...
BUT THERE REMAINS UNCERTAINTY ON HOW FAR NORTH ACROSS THE AREA IT
WILL EXTEND... SO PLAYED THINGS OPTIMISTIC FOR NOW AND DID NOT
INCLUDE TOO MUCH OF A MENTION.
KMSP...CONFIDENCE IN FORECAST SPECIFICS IS LOW GIVEN SLOWLY MOVING
FRONT/TROUGH AND LINGERING BAROCLINIC ZONE WITHOUT ANY SIGNIFICANT
FORCING FEATURE OVER THE AREA. FOG ISSUES AND PERHAPS SOME STRATUS
COULD BE WORSE THAN INDICATED LATER TONIGHT... AND PCPN COULD BE
MORE WIDESPREAD INTO THE AREA LATER TONIGHT.
/OUTLOOK FOR KMSP/
SATURDAY NIGHT...VFR. WEST WIND LESS THAN 10 KT BECOMING NORTH.
SUNDAY...VFR. NORTHWEST WIND 5 TO 15 KT.
SUNDAY NIGHT. MVFR POSSIBLE WITH A CHANCE OF SHRA/TSRA. NORTHWEST
WIND 5 TO 15 KT. MONDAY...MVFR POSSIBLE WITH A CHANCE OF
SHRA/TSRA. NORTHWEST WIND 10 TO 20 KT. MONDAY NIGHT...MVFR
POSSIBLE. NORTHWEST WIND 5 TO 10 KT. TUESDAY...VFR. NORTHWEST WIND
LESS THAN 10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...TRH
LONG TERM...LS
AVIATION...TRH
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
326 PM CDT FRI JUL 11 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 326 PM CDT FRI JUL 11 2014
A WARM FRONT EXTENDING FROM NEAR IMPERIAL IN SOUTHWEST NEBRASKA TO
OMAHA IN EASTERN NEBRASKA...WILL REMAIN NEARLY STATIONARY THROUGH
TONIGHT. A SOUTHERLY LOW LEVEL JET WILL DEVELOP ACROSS WESTERN
KANSAS THIS EVENING. THE NOSE OF THE JET WILL BE DIRECTED AT
SOUTHWEST NEBRASKA THROUGH THE EVENING HOURS...AND THEN VEER
SOUTHWEST TOWARD SOUTH CENTRAL NEBRASKA AFTER MIDNIGHT.
A COUPLE OF DIFFERENT SCENARIOS ARE POSSIBLE REGARDING CONVECTIVE
CHANCES LATE THIS AFTERNOON AND EVENING. FIRST...THUNDERSTORMS
CURRENTLY DEVELOPING NEAR THE LARAMIE RANGE ACROSS SOUTHEAST WYOMING
/AIDED BY A FAIRLY SIGNIFICANT SHORTWAVE ALOFT MOVING EASTWARD
TOWARD THAT AREA/ SHOULD PROPAGATE EAST INTO WESTERN NEBRASKA THIS
EVENING. DEEP MOISTURE AND UNSTABLE CONDITIONS RESIDE ACROSS MUCH OF
NEBRASKA TO THE NORTH OF THE AFOREMENTIONED WARM FRONT. LOW LEVEL
EASTERLY SURFACE WINDS NORTH OF FRONT WILL AID STORM-RELATIVE
INFLOW...AND THE DEVELOPING SOUTHERLY LOW LEVEL JET SHOULD FURTHER
SUPPORT INFLOW AS WELL AS CONTINUED MOISTURE ADVECTION. DUE TO THE
SEEMINGLY FAVORABLE CONDITIONS...THESE STORMS WILL LIKELY FORM INTO
A CLUSTER AND POSSIBLY AN MCS AS THEY MOVE EAST TOWARD CENTRAL/NORTH
CENTRAL NEBRASKA MID EVENING ONWARD. THE SECOND AND LESS LIKELY
SCENARIO WOULD BE FOR A FEW SURFACE BASED STORMS TO DEVELOP ACROSS
FAR SOUTHWEST NEBRASKA NEAR THE WARM FRONT LATE THIS AFTERNOON AND
EVENING. THESE WOULD LIKELY BE HIGH BASED AND ISOLATED. THE LATEST
RUN OF THE HRRR MODEL SUPPORTS THE FIRST SCENARIO...AND THE FORECAST
WILL BE TAILORED IN THAT DIRECTION.
A SHORTWAVE DISTURBANCE WILL BE CROSSING THE AREA SATURDAY
MORNING...WITH AT LEAST SCATTERED ELEVATED SHOWERS AND THUNDERSTORMS
EXPECTED TO BE ONGOING THROUGH THE MORNING HOURS. A WEAK COLD FRONT
WILL DROP SOUTH THROUGH THE AREA SATURDAY AFTERNOON. THIS FRONT WILL
MERGE WITH THE WARM FRONT ACROSS SOUTHERN NEBRASKA OR NORTHERN
KANSAS...WHERE SURFACE BASED CONVECTION IS POSSIBLE LATE IN THE
AFTERNOON. ACROSS OUR AREA...MOIST EAST/NORTHEAST UPSLOPE LOW LEVEL
FLOW WILL CONTINUE...AND THUNDERSTORMS SHOULD DEVELOP EASTWARD OFF
THE HIGHER TERRAIN INTO WESTERN NEBRASKA LATE SATURDAY AFTERNOON AND
EVENING. ACTIVITY SHOULD REMAIN SCATTERED AS FORCING IS EXPECTED TO
BE WEAK AS SHORTWAVE PUSHES EAST OF THE AREA. WILL LIMIT POPS TO 30
PERCENT FOR MOST LOCATIONS DURING THE AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 326 PM CDT FRI JUL 11 2014
THE MAIN POINTS OF THE LONG TERM FORECAST INCLUDE COOLER
TEMPERATURES AND A DECREASE IN CHANCES OF SHOWERS/THUNDERSTORMS. THE
PERIOD STARTS OFF WITH AN UPPER LEVEL DISTURBANCE PASSING THROUGH
THE NORTHERN PLAINS INTO THE GREAT LAKES REGION. A STATIONARY FRONT
WILL EXIST TO THE SOUTH IN KS SATURDAY NIGHT...WHILE A COLD FRONT
ASSOCIATED WITH THE DISTURBANCE PUSHES SOUTH ACROSS THE DAKOTAS. A
STRONGER UPPER LEVEL WAVE ROTATING AROUND THE MAIN UPPER LEVEL LOW
WILL MOVE SOUTHEAST ACROSS ND/MN/WI ON MONDAY. STRONG SURFACE HIGH
PRESSURE WILL FOLLOW THIS UPPER LOW AND HELP PUSH UNSEASONABLY COOL
TEMPERATURES INTO THE REGION ON MONDAY. THE HIGH WILL SETTLE IN OVER
THE AREA MONDAY NIGHT...MAKING FOR A COOL TUESDAY MORNING. WITH THE
HIGH SLOW TO MOVE EAST...HIGHS WILL BE IN THE 70S ON TUESDAY AND
WEDNESDAY. TEMPERATURES BEGIN TO REBOUND CLOSER TO NORMAL TOWARD THE
END OF THE WEEK UNDER UPPER LEVEL RIDGING.
STRONG THUNDERSTORMS WILL BE POSSIBLE SATURDAY NIGHT AND SUNDAY
NIGHT. MODERATE INSTABILITY AND DEEP SHEAR OF 30-40 KTS MAY LEAD TO
A FEW SEVERE STORMS SATURDAY NIGHT. INSTABILITY AND SHEAR BOTH LOOK
A LITTLE WEAKER FOR SUNDAY...LIMITING THE SEVERE RISK A BIT COMPARED
TO SATURDAY NIGHT. THERE IS ALSO MORE UNCERTAINTY REGARDING THE
LOCATION OF THE FRONT AND INSTABILITY ON SUNDAY. A FEW OTHER CHANCES
WILL EXIST ACROSS THE AREA EARLY IN THE WEEK...PRIMARILY IN THE SW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1236 PM CDT FRI JUL 11 2014
A WARM FRONT WILL EXTEND FROM NEAR KGLD TO KLXN TO KGRI LATE THIS
AFTERNOON. UNSTABLE CONDITIONS WILL BE IN PLACE TO THE NORTH OF THE
FRONT...BUT A STOUT CAPPING INVERSION ALOFT WILL KEEP THUNDERSTORM
ACTIVITY ISOLATED AT BEST THROUGH EARLY THIS EVENING. BY MID
EVENING...A LINE OF STRONG TO POSSIBLE SEVERE THUNDERSTORMS IS
EXPECTED TO MOVE EAST OUT OF NORTHEAST COLORADO AND THE NEBRASKA
PANHANDLE. THIS ACTIVITY SHOULD REMAINED CONFINED TO AREAS GENERALLY
ALONG AND ESPECIALLY NORTH OF INTERSTATE 80. STRONG WINDS WILL BE
LIKELY WITH THIS ACTIVITY. THIS COULD IMPACT BOTH THE KLBF AND KVTN
TAF SITES THROUGH THE EVENING HOURS. VFR CONDITIONS ARE EXPECTED
OVERALL...BUT LOCAL IFR CONDITIONS ARE POSSIBLE NEAR ANY
THUNDERSTORM ACTIVITY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TAYLOR
LONG TERM...KNUTSVIG
AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
328 PM MDT FRI JUL 11 2014
.SYNOPSIS...
AN ACTIVE SHOWER AND THUNDERSTORM PERIOD IS ON TAP FOR THE NEXT
WEEK. SHOWERS AND THUNDERSTORMS WILL FAVOR WESTERN AND NORTHERN
NEW MEXICO FOR THE REST OF TODAY AND SATURDAY...BEFORE THE FOCUS
SHIFTS...OR PERHAPS JUST SPREADS...INTO EASTERN NEW MEXICO SUNDAY
THROUGH MUCH OF NEXT WEEK. SEVERAL BACK DOOR COLD FRONT NEXT WEEK
WILL BE A FOCUS FOR PRECIPITATION ACROSS THE PLAINS. THIS WILL
ALSO COOL TEMPERATURES BACK BELOW NORMAL. STORMS WILL MOVE SLOWLY
ALL WEEK...THUS THE POTENTIAL FOR FLOODING EXISTS DAILY...
ESPECIALLY OVER BURN SCARS.
&&
.DISCUSSION...
WATER VAPOR AND VIS SATELLITE IMAGERY SHOWING SUBSTANTIAL DRY AIR
AND SUBSIDENCE MOVING INTO MUCH OF EASTERN AND PORTIONS OF CENTRAL
NM AHEAD OF AN EASTERLY WAVE. MONSOONAL PLUME IS CERTAINLY FOCUSED
ACROSS WESTERN NM WHERE FLASH FLOOD WATCH IS IN PLACE AND PWATS ARE
AT OR JUST ABOVE NORMAL. APPEARS LIKE THE DRY AIR HAS PUSHED FURTHER
WEST THAN MODELS SUGGESTED...BUT THE 17Z HRRR APPEARS TO BE ON TRACK
WITH SHIFTING THE FOCUS FOR PRECIPITATION TONIGHT FURTHER TO THE
NORTHWEST...WHERE THETA-E RIDGE AXIS LIES. HAVE INCREASED POPS IN
THIS AREA AS THESE LOCALES HAVE RECEIVED PLENTY OF SUNSHINE
TODAY...AND WITH GOOD INSTABILITY AND STORM MOTIONS GENERALLY TOWARD
THE WEST...IT MAKES SENSE THAT STORMS FAVOR THAT AREA TONIGHT. THERE
IS ALSO A PRECARIOUS BOUNDARY RIGHT ALONG THE NE NM/SE CO BORDER
THAT HAS RECENTLY SPARKED AN ISOLATED STORM. LOOKS LIKE THIS
BOUNDARY WILL STAY NORTH OF THE AREA...THUS HAVE KEPT POPS AT A
MINIMUM. ABQ AREA WILL BE TRICKY...AS STORMS THUS FAR HAVE STRUGGLED
THAT HAVE FORMED ON THE SANDIAS DUE TO THE DRY AIR...BUT ADDITIONAL
STORMS HAVE DEVELOPED EAST OF THE MTNS AND BASED ON STORM
MOTIONS...SHOULD ARRIVE IN ABQ PRIOR TO 6PM IF THEY HOLD TOGETHER.
THE EASTERLY WAVE SLIDES SOUTH OF THE STATE TONIGHT. THERE WILL
STILL BE SOME DRY AIR IN PLACE OVER THE EAST TOMORROW...BUT THE UPPER
HIGH THAT IS OVER THE NE NOW...WILL START TO SHIFT WNW. THIS WILL
MEAN LITTLE CHANGE FOR STORM COVERAGE AND PLACEMENT FOR SATURDAY.
MOST STORMS WILL TRAVEL WESTWARD...EXCEPT STORMS ACROSS THE NE WHICH
MAY DRIFT EASTWARD. THESE NE STORMS WILL DEVELOP ALONG A WEAK COLD
FRONT THAT WILL GENERALLY STALL ACROSS THE AREA. OUTFLOW BOUNDARIES
LATER IN THE EVENING MAY PUSH IT FURTHER SOUTH HOWEVER.
THE WEAK FRONT ACROSS THE NE LOOKS TO BE REINFORCED A BIT ON
SUNDAY...AND THIS MAY PUSH THE FRONT FURTHER SOUTH. HAVE EXPANDED
CHANCE POPS ACROSS THE NE FOR THIS REASON. OTHERWISE...THE UPPER
HIGH WILL BE CENTERED ACROSS THE GREAT BASIN...WHICH GENERALLY TILTS
THE WEAK MONSOONAL PLUME OVER INTO MORE OF THE STATE.
WITH AN EXISTING BOUNDARY IN PLAY ACROSS THE EAST...HAVE INCREASED
POPS ACROSS THE PLAINS FOR MONDAY. THEN THE STRONGER
FRONT...ASSOCIATED WITH THE STRONG UPPER LOW ACROSS THE GREAT
LAKES...WILL ARRIVE MONDAY NIGHT AND TUESDAY...PUTTING ADDITIONAL
FOCUS FOR STORMS ACROSS THE EAST. THE WEST WILL REMAIN ACTIVE
TOO...ESPECIALLY IF THE FRONT PUSHES THRU THE GAPS.
NORTHWEST FLOW WILL BE IN PLACE OVER NM MID WEEK AS THE PATTERN
BECOMES QUITE AMPLIFIED. THIS IS NOT GOOD IN TERMS OF RECEIVING
MOISTURE FROM THE SOUTH...THE TRADITIONAL MONSOON WAY...BUT REGULAR
DISTURBANCES IN THE NORTHWEST FLOW WILL CONTINUE USHER IN MOISTURE
ACROSS THE EAST BEHIND BACK DOOR FRONTS...AND ONE SUCH STRONG FRONT
LOOKS TO ARRIVE WEDNESDAY NIGHT...WHICH MAY PUSH THRU THE GAPS OF
THE CENTRAL MTN CHAIN ONCE AGAIN. THUS...AN ACTIVE PATTERN WILL
PERSIST THRU THE NEXT WEEK. MODELS ARE HINTING AT REBUILDING THE
UPPER HIGH OVER NM NEXT WEEKEND. STAY TUNED.
34
&&
.FIRE WEATHER...
AN ACTIVE MONSOON MOISTURE PLUME WILL CONTINUE WITH WETTING RAIN
OVER THE WESTERN...CENTRAL AND NORTHERN CENTRAL ZONES THIS AFTERNOON
AND SATURDAY. AN EXPANSION IN THE WETTING RAIN PATTERN WILL COMMENCE
ON SUNDAY WHEN A BACK DOOR FRONT SUPPORTS INCREASED CHANCES OF
PRECIPITATION ACROSS NORTHEASTERN ZONES. A WIDESPREAD WET PATTERN
WILL THEN BE IN PLACE FOR THE WORK WEEK WITH INCREASED CHANCES OF
BURN SCAR FLOODING.
UPPER LEVEL HIGH CURRENTLY IS CENTERED OVER EXTREME EASTERN TEXAS
WITH AN EASTERLY WAVE CENTERED JUST SOUTH OF THE BIG BEND AREA AND
SLOWLY DRIFTING TO THE NORTHWEST. A BROAD AREA OF SUBSIDENCE AHEAD
OF THE WAVE IS USHERING IN MID LEVEL DRY AIR INTO EASTERN NEW
MEXICO...THUS SHUTTING DOWN WETTING RAIN ACROSS THE EASTERN ZONES.
SURFACE MOISTURE REMAINS IN PLACE ACROSS THE EAST WHERE SOME
EXCELLENT RH RECOVERIES ARE EXPECTED TONIGHT...WITH MAINLY GOOD
VALUES ELSEWHERE.
UPCOMING PATTERN CHANGES ARE CURRENTLY DEVELOPING WELL NORTH OF NEW
MEXICO AS AN UPPER RIDGE BUILDS OVER THE WEST COAST AND AN UPPER LOW
DEEPENS OVER CENTRAL CANADA. THIS PATTERN WILL AMPLIFY STARTING
SUNDAY AS THE HIGH CONTINUES TO STRENGTHEN AS THE LOW MOVES TOWARD
THE GREAT LAKES. THE FIRST OF SEVERAL BACK DOOR FRONTS WILL EDGE
INTO THE NORTHEAST ON SUNDAY...WITH COOLER TEMPERATURES...ENHANCED
LOW LEVEL MOISTURE AND INCREASED CHANCES OF WETTING RAIN FROM THE
NORTH CENTRAL MOUNTAIN TO THE NORTHEAST PLAINS. MONSOON PLUME WILL
PERSIST ACROSS THE WEST THUS ONLY THE EXTREME EAST CENTRAL PLAINS
LOOK TO REMAIN DRY.
FOR THE WORK WEEK...THE AMPLIFIED PATTERN PERSISTS WITH HIGH
PRESSURE TO THE WEST AND REGULAR WIND SHIFTS INTO THE NORTHEAST
MAINTAINING MOIST LOW LEVEL EAST TO SOUTHEAST FLOW ACROSS THE
EASTERN PLAINS THROUGH THE WORK WEEK. EXTEND MODELS SHOW REASONABLE
AGREEMENT WITH UPPER LEVEL DISTURBANCES IN THE NORTHWEST FLOW ALOFT
ON EARLY WEDNESDAY AND AGAIN ON THURSDAY. WHILE THERE IS STILL
UNCERTAINTY IN THE TIMING OF SPECIFIC FEATURES...THE CHANCES FOR
WIDESPREAD WETTING RAIN FOR THE WORK WEEK...RESULTING IN POSSIBLE BURN
SCAR FLOODING... ARE FAIRLY CERTAIN. OVERNIGHT RH RECOVERIES LOOK TO
BE GOOD TO EXCELLENT THROUGH THE WORK WEEK. PERIODS OF POOR TO FAIR
VENTILATION CAN BE EXPECTED...ESPECIALLY ACROSS THE NORTH ON
SUNDAY...PORTIONS OF THE WEST ON MONDAY AND TUESDAY...AND THE
NORTHEAST TO EAST WEDNESDAY INTO THURSDAY.
05
&&
.AVIATION...
18Z TAF CYCLE
AMPLE MONSOON MOISTURE MOISTURE REMAINS IN PLACE ACROSS WESTERN
ZONES WHILE DRIER MID LEVEL AIR HAS MOVED OVER EASTERN ZONES.
THUNDERSTORMS WILL BE PLENTIFUL THIS AFTERNOON MAINLY ACROSS THE
NORTHERN AND WESTERN HIGHER TERRAIN. THUNDERSTORMS WILL BE NEARLY
STATIONARY OR SLOW MOVING AND CAPABLE OF MODERATE TO HEAVY
DOWNPOURS RESULTING IN LOCAL MVFR CONDITIONS AND MOUNTAIN
OBSCURATIONS. GUSTY OUTFLOWS UP TO 45 KT WILL ACCOMPANY THESE
STORMS. SHOWERS WILL LINGER DURING THE OVERNIGHT HOURS ESPECIALLY
CENTRAL VALLEYS AND WEST CENTRAL OR SOUTHWEST ZONES WITH
OCCASIONAL MVFR CONDITIONS. SURFACE MOISTURE WILL PERSIST ACROSS
THE EAST AND LOW CLOUDS ARE POSSIBLE OVER PORTIONS OF THE EASTERN
PLAINS SATURDAY MORNING...WITH BEST CHANCES AT KROW AND KCVS AND
LESSER CHANCES AT KTCC AND KLVS.
05
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 65 93 65 92 / 30 20 20 30
DULCE........................... 53 88 51 86 / 40 30 40 50
CUBA............................ 56 85 56 82 / 50 50 60 50
GALLUP.......................... 59 88 59 87 / 50 40 30 40
EL MORRO........................ 57 80 56 79 / 50 60 50 40
GRANTS.......................... 58 86 57 85 / 50 40 40 30
QUEMADO......................... 58 80 57 81 / 50 50 40 40
GLENWOOD........................ 60 87 59 88 / 40 40 40 30
CHAMA........................... 49 80 48 78 / 60 50 60 60
LOS ALAMOS...................... 61 83 61 79 / 40 40 50 40
PECOS........................... 57 79 57 76 / 40 50 40 40
CERRO/QUESTA.................... 52 80 54 76 / 50 50 50 50
RED RIVER....................... 47 74 48 69 / 50 60 60 70
ANGEL FIRE...................... 44 78 43 73 / 40 60 50 60
TAOS............................ 53 85 54 80 / 40 40 50 40
MORA............................ 54 79 54 73 / 30 50 40 50
ESPANOLA........................ 60 89 61 85 / 40 30 50 30
SANTA FE........................ 59 83 60 79 / 30 40 40 40
SANTA FE AIRPORT................ 60 88 61 85 / 30 30 40 30
ALBUQUERQUE FOOTHILLS........... 67 89 68 88 / 30 30 30 30
ALBUQUERQUE HEIGHTS............. 69 91 70 90 / 20 20 30 20
ALBUQUERQUE VALLEY.............. 67 92 67 91 / 20 20 30 20
ALBUQUERQUE WEST MESA........... 68 91 69 90 / 20 20 30 20
LOS LUNAS....................... 65 93 65 92 / 20 10 30 20
RIO RANCHO...................... 68 93 69 90 / 20 20 40 20
SOCORRO......................... 70 94 70 94 / 20 10 20 20
SANDIA PARK/CEDAR CREST......... 62 86 62 84 / 30 40 40 30
TIJERAS......................... 62 87 62 85 / 30 30 40 30
MORIARTY/ESTANCIA............... 57 84 57 83 / 20 40 30 30
CLINES CORNERS.................. 57 83 59 81 / 10 30 20 20
GRAN QUIVIRA.................... 61 84 62 83 / 20 30 20 20
CARRIZOZO....................... 64 85 64 85 / 10 20 20 20
RUIDOSO......................... 55 81 56 81 / 10 30 20 30
CAPULIN......................... 62 82 59 73 / 5 30 50 60
RATON........................... 59 86 60 78 / 5 30 40 50
SPRINGER........................ 61 88 62 81 / 5 20 20 50
LAS VEGAS....................... 55 84 56 79 / 10 20 20 30
CLAYTON......................... 64 91 65 84 / 5 5 20 50
ROY............................. 64 86 64 81 / 5 10 10 50
CONCHAS......................... 68 92 68 88 / 5 0 5 30
SANTA ROSA...................... 65 89 67 86 / 5 0 5 20
TUCUMCARI....................... 68 93 68 92 / 5 5 5 20
CLOVIS.......................... 62 88 63 89 / 5 5 5 10
PORTALES........................ 64 89 64 90 / 5 5 5 5
FORT SUMNER..................... 67 89 67 90 / 5 5 5 10
ROSWELL......................... 66 91 67 94 / 5 5 5 5
PICACHO......................... 60 85 62 86 / 5 5 5 10
ELK............................. 57 80 58 80 / 10 10 10 30
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 8 PM MDT THIS EVENING FOR THE FOLLOWING
ZONES...NMZ504-506>508-511.
&&
$$
34
AREA FORECAST DISCUSSION
NWS BISMARCK ND
116 PM CDT FRI JUL 11 2014
.UPDATE...
ISSUED AT 115 PM CDT FRI JUL 11 2014
QUICK UPDATE TO FURTHER EXPAND ISOLATED SHOWERS/THUNDERSTORMS FROM
SOUTHWEST THROUGH SOUTH CENTRAL AND INTO THE JAMES RIVER VALLEY.
OTHERWISE NO OTHER CHANGES FROM PREVIOUS FORECAST.
UPDATE ISSUED AT 1210 PM CDT FRI JUL 11 2014
LATEST LOCAL/REGIONAL RADAR SHOWS ISOLATED THUNDERSTORMS INTO
SOUTHWEST NORTH DAKOTA...PART OF THE SAME SHORTWAVE ENERGY AND JET
SUPPORT THAT WAS ACROSS THE NORTHWEST EARLIER THIS MORNING.
OBSERVATIONS OUTSIDE THE BISMARCK OFFICE SHOW A MID LEVEL CAP IS
CURRENTLY IN PLACE. HOWEVER...DECENT MID LEVEL LAPSE RATES AND
SHEAR PER SPC MESOANALYSIS IS MAINTAINING CURRENT AREA OF
PRECIPITATION AS IT CONTINUES TO ADVANCE EAST. HAVE NUDGED THE
ISOLATED PRECIPITATION AREA SLIGHTLY FARTHER EAST THIS AFTERNOON
GIVEN LATEST TRENDS. OTHERWISE THE REST OF THE FORECAST REMAINS IN
GOOD SHAPE
FOR TONIGHT...THE LATEST GFS IS MUCH DRIER FOR THE OVERNIGHT
PERIOD INTO SATURDAY MORNING...WHICH IS OPPOSITE OF THE 12Z NAM
SOLUTION. THE LATEST CANADIAN GEM MAINTAINS PRECIPITATION OVER
SOUTHWEST AND SOUTHERN NORTH DAKOTA TONIGHT INTO SATURDAY MORNING.
WILL AWAIT THE ECMWF BEFORE MAKING CHANGES AND COLLABORATE WITH
NEIGHBORING OFFICES BEFORE MAKING CHANGES.
UPDATE ISSUED AT 802 AM CDT FRI JUL 11 2014
LATEST SURFACE ANALYSIS PLACES THE COLD FRONT INTO THE JAMES RIVER
VALLEY WITH 3HR PRESSURE RISES INCREASING RAPIDLY FARTHER WEST.
PATCHY FOG MAINLY ALONG AND AHEAD OF THE FRONT CONTINUES BUT
IMPROVING CONDITIONS HAVE BEGUN AS EXPECTED FROM PREVIOUS FORECAST.
AREA OF SHOWERS AND ISOLATED THUNDERSTORMS IN NORTHEAST MONTANA
ALSO WEAKENING WITH TIME AS THEY MOVE INTO NORTHWESTERN NORTH
DAKOTA. THE LATEST HRRR AND RAP13 SHOW THESE SHOWERS WANING
THROUGH THE MORNING HOURS BEFORE ENDING BETWEEN 16Z-17Z. OVERALL
THE CURRENT GRIDDED FORECAST IN ON TRACK.
UPDATE ISSUED AT 609 AM CDT FRI JUL 11 2014
AREA OF SHOWERS AND THUNDERSTORMS OVER NORTHEAST MONTANA NEAR
RIGHT ENTRANCE REGION OF UPPER JET KEEP TRYING TO PUSH EAST...BUT
STRUGGLE TO HOLD TOGETHER ONCE THEY APPROACH THE STATE LINE.
EXPECT A FEW WILL START TO HOLD TOGETHER SO WILL MAINTAIN LOW POPS
AND PUSH THE POPS EAST A LITTLE. PATCHY FOG CONTINUES OVER THE
AREA...BUT EXPECT THIS TO IMPROVE NOT LONG AFTER SUNRISE. UPDATES
HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT FRI JUL 11 2014
MAIN FORECAST HIGHLIGHT IN THE SHORT TERM PERIOD WILL BE THE
CHANCE FOR SHOWERS AND THUNDERSTORMS NOW THROUGH TONIGHT.
CURRENTLY...FRONTAL BOUNDARY CONTINUES TO MOVE SLOWLY SOUTH AND
EAST ACROSS THE STATE...NOW POSITIONED ACROSS CENTRAL NORTH
DAKOTA. THE OUTFLOW BOUNDARY WHICH EARLIER PRODUCED A FEW
STRONGER STORMS NORTH CENTRAL...CONTINUES TO GENERATE WEAK
CONVECTION AS IT MOVES SOUTH. PAST HOUR HAVE SEEN WEAK ECHOS
DEVELOP ACROSS SHERIDAN AND NORTHERN BURLEIGH COUNTIES. WILL
MAINTAIN A MENTION OF SHOWERS/THUNDERSTORMS FOR THESE AREAS AND
ACROSS MY SOUTHEAST THROUGH 12Z FOR THIS FEATURE. ADDITIONAL
SHOWERS AND THUNDERSTORMS DEVELOPED THE PAST FEW HOURS ACROSS
NORTHERN MONTANA UNDER THE RIGHT ENTRANCE REGION OF AN UPPER LEVEL
JET STREAK MOVING SLOWLY EAST ALONG THE INTERNATIONAL BORDER.
SOME OF THIS ACTIVITY MAY ENTER WESTERN NORTH DAKOTA...MAINLY AFTER
12Z.
WILL ALSO MAINTAIN PATCHY FOG WORDING THROUGH 15Z BASED ON LATEST
OBSERVATIONS.
FOR TODAY...FORCING ASSOCIATED WITH THE UPPER JET STREAK REALLY
DOES NOT MATERIALIZE ACROSS NORTH DAKOTA UNTIL TONIGHT WHEN
DIVERGENCE ALOFT INCREASES. MAY SEE SOME ELEVATED
SHOWERS/THUNDERSTORMS THIS MORNING/AFTERNOON WEST...BUT DOES APPEAR
MOST SHOWER/THUNDERSTORM ACTIVITY WILL NOT GET GOING UNTIL AFTER
00Z. WHEN IT DOES...EXPECT PRECIPITATION TO BE CONFINED TO THE
SOUTHERN ONE HALF...IF NOT SOUTHERN ONE THIRD...WITH SUBSIDENCE
ASSOCIATED WITH SURFACE HIGH PRESSURE OVER MY NORTH. THE THREAT
FOR SEVERE WEATHER SHOULD REMAIN OFF TO OUR SOUTH WITH MODELS
INDICATING A STABLE AIRMASS OVER MUCH OF THE STATE. THE FAR SOUTH
WILL SEE THE BEST CHANCE FOR A STRAY STRONGER STORM OR
TWO...MAINLY LATE THIS AFTERNOON OR EVENING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI JUL 11 2014
ON SATURDAY...DEEPENING UPPER LOW SLIDES DOWN THE WESTERN SHORES OF
HUDSON BAY WHILE A FEW WAVES CONTINUE TO SWING THROUGH CYCLONIC FLOW
ALOFT THRU THE AREA. THIS WILL KEEP CHANCES FOR SHOWERS/STORMS IN
THE FORECAST PRIMARILY OVER SOUTHERN NORTH DAKOTA.
SUNDAY INTO MONDAY...AFOREMENTIONED UPPER LOW CONTINUES ITS
SOUTHERLY SLIDE TOWARDS NORTHERN MINNESOTA/LAKE SUPERIOR. MODELS
CONTINUE TO BE IN PRETTY GOOD AGREEMENT WITH THE TRACK OF THIS
SYSTEM. COOLER AIRMASS SWINGING AROUND THE LOW WILL PUSH INTO THE
AREA...WITH THE MAIN PUSH COMING LATE SUNDAY INTO MONDAY. THIS WILL
BRING WELL BELOW AVERAGE TEMPS TO THE REGION EARLY NEXT WEEK...WITH
MOST LOCATIONS SEEING HIGHS AROUND 15 TO 20 DEGREES BELOW AVERAGE ON
MONDAY. WILL HAVE TO WATCH THE TREND WITH THIS AS TEMPS MAY NEED TO
BE LOWERED EVEN FURTHER. A FEW SHOWERS WILL BE POSSIBLE ON MONDAY AS
VARIETY OF WAVES WRAP THROUGH CYCLONIC FLOW...PARTICULARLY FROM THE
TURTLE MOUNTAINS TO THE JAMES RIVER VALLEY.
FOR THE REMAINDER OF THE EXTENDED...UPPER LOW MOVES OFF TO THE EAST
WHILE RIDGE OVER THE WESTERN CONUS KEEPS NORTHWEST FLOW OVER OUR
AREA KEEPING CONDITIONS MAINLY DRY. TEMPERATURES WILL WARM THROUGH
MID-WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1210 PM CDT FRI JUL 11 2014
VFR CIGS/VSBYS EXPECTED THROUGH THE PERIOD. EXPECT ISOLATED SHOWERS
AND THUNDERSTORMS THROUGH 00Z SATURDAY AT KDIK. THERE WILL BE A
RENEWED THREAT FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
AT KDIK MAINLY AFTER 05Z SATURDAY. THIS MAY REACH KBIS AND HENCE A
VCSH IS IN THE OVERNIGHT PERIOD FORECAST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...JJS
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1210 PM CDT FRI JUL 11 2014
.UPDATE...
ISSUED AT 1210 PM CDT FRI JUL 11 2014
LATEST LOCAL/REGIONAL RADAR SHOWS ISOLATED THUNDERSTORMS INTO
SOUTHWEST NORTH DAKOTA...PART OF THE SAME SHORTWAVE ENERGY AND JET
SUPPORT THAT WAS ACROSS THE NORTHWEST EARLIER THIS MORNING.
OBSERVATIONS OUTSIDE THE BISMARCK OFFICE SHOW A MID LEVEL CAP IS
CURRENTLY IN PLACE. HOWEVER...DECENT MID LEVEL LAPSE RATES AND
SHEAR PER SPC MESOANALYSIS IS MAINTAINING CURRENT AREA OF
PRECIPITATION AS IT CONTINUES TO ADVANCE EAST. HAVE NUDGED THE
ISOLATED PRECIPITATION AREA SLIGHTLY FARTHER EAST THIS AFTERNOON
GIVEN LATEST TRENDS. OTHERWISE THE REST OF THE FORECAST REMAINS IN
GOOD SHAPE
FOR TONIGHT...THE LATEST GFS IS MUCH DRIER FOR THE OVERNIGHT
PERIOD INTO SATURDAY MORNING...WHICH IS OPPOSITE OF THE 12Z NAM
SOLUTION. THE LATEST CANADIAN GEM MAINTAINS PRECIPITATION OVER
SOUTHWEST AND SOUTHERN NORTH DAKOTA TONIGHT INTO SATURDAY MORNING.
WILL AWAIT THE ECMWF BEFORE MAKING CHANGES AND COLLABORATE WITH
NEIGHBORING OFFICES BEFORE MAKING CHANGES.
UPDATE ISSUED AT 802 AM CDT FRI JUL 11 2014
LATEST SURFACE ANALYSIS PLACES THE COLD FRONT INTO THE JAMES RIVER
VALLEY WITH 3HR PRESSURE RISES INCREASING RAPIDLY FARTHER WEST.
PATCHY FOG MAINLY ALONG AND AHEAD OF THE FRONT CONTINUES BUT
IMPROVING CONDITIONS HAVE BEGUN AS EXPECTED FROM PREVIOUS FORECAST.
AREA OF SHOWERS AND ISOLATED THUNDERSTORMS IN NORTHEAST MONTANA
ALSO WEAKENING WITH TIME AS THEY MOVE INTO NORTHWESTERN NORTH
DAKOTA. THE LATEST HRRR AND RAP13 SHOW THESE SHOWERS WANING
THROUGH THE MORNING HOURS BEFORE ENDING BETWEEN 16Z-17Z. OVERALL
THE CURRENT GRIDDED FORECAST IN ON TRACK.
UPDATE ISSUED AT 609 AM CDT FRI JUL 11 2014
AREA OF SHOWERS AND THUNDERSTORMS OVER NORTHEAST MONTANA NEAR
RIGHT ENTRANCE REGION OF UPPER JET KEEP TRYING TO PUSH EAST...BUT
STRUGGLE TO HOLD TOGETHER ONCE THEY APPROACH THE STATE LINE.
EXPECT A FEW WILL START TO HOLD TOGETHER SO WILL MAINTAIN LOW POPS
AND PUSH THE POPS EAST A LITTLE. PATCHY FOG CONTINUES OVER THE
AREA...BUT EXPECT THIS TO IMPROVE NOT LONG AFTER SUNRISE. UPDATES
HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 325 AM CDT FRI JUL 11 2014
MAIN FORECAST HIGHLIGHT IN THE SHORT TERM PERIOD WILL BE THE
CHANCE FOR SHOWERS AND THUNDERSTORMS NOW THROUGH TONIGHT.
CURRENTLY...FRONTAL BOUNDARY CONTINUES TO MOVE SLOWLY SOUTH AND
EAST ACROSS THE STATE...NOW POSITIONED ACROSS CENTRAL NORTH
DAKOTA. THE OUTFLOW BOUNDARY WHICH EARLIER PRODUCED A FEW
STRONGER STORMS NORTH CENTRAL...CONTINUES TO GENERATE WEAK
CONVECTION AS IT MOVES SOUTH. PAST HOUR HAVE SEEN WEAK ECHOS
DEVELOP ACROSS SHERIDAN AND NORTHERN BURLEIGH COUNTIES. WILL
MAINTAIN A MENTION OF SHOWERS/THUNDERSTORMS FOR THESE AREAS AND
ACROSS MY SOUTHEAST THROUGH 12Z FOR THIS FEATURE. ADDITIONAL
SHOWERS AND THUNDERSTORMS DEVELOPED THE PAST FEW HOURS ACROSS
NORTHERN MONTANA UNDER THE RIGHT ENTRANCE REGION OF AN UPPER LEVEL
JET STREAK MOVING SLOWLY EAST ALONG THE INTERNATIONAL BORDER.
SOME OF THIS ACTIVITY MAY ENTER WESTERN NORTH DAKOTA...MAINLY AFTER
12Z.
WILL ALSO MAINTAIN PATCHY FOG WORDING THROUGH 15Z BASED ON LATEST
OBSERVATIONS.
FOR TODAY...FORCING ASSOCIATED WITH THE UPPER JET STREAK REALLY
DOES NOT MATERIALIZE ACROSS NORTH DAKOTA UNTIL TONIGHT WHEN
DIVERGENCE ALOFT INCREASES. MAY SEE SOME ELEVATED
SHOWERS/THUNDERSTORMS THIS MORNING/AFTERNOON WEST...BUT DOES APPEAR
MOST SHOWER/THUNDERSTORM ACTIVITY WILL NOT GET GOING UNTIL AFTER
00Z. WHEN IT DOES...EXPECT PRECIPITATION TO BE CONFINED TO THE
SOUTHERN ONE HALF...IF NOT SOUTHERN ONE THIRD...WITH SUBSIDENCE
ASSOCIATED WITH SURFACE HIGH PRESSURE OVER MY NORTH. THE THREAT
FOR SEVERE WEATHER SHOULD REMAIN OFF TO OUR SOUTH WITH MODELS
INDICATING A STABLE AIRMASS OVER MUCH OF THE STATE. THE FAR SOUTH
WILL SEE THE BEST CHANCE FOR A STRAY STRONGER STORM OR
TWO...MAINLY LATE THIS AFTERNOON OR EVENING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 325 AM CDT FRI JUL 11 2014
ON SATURDAY...DEEPENING UPPER LOW SLIDES DOWN THE WESTERN SHORES OF
HUDSON BAY WHILE A FEW WAVES CONTINUE TO SWING THROUGH CYCLONIC FLOW
ALOFT THRU THE AREA. THIS WILL KEEP CHANCES FOR SHOWERS/STORMS IN
THE FORECAST PRIMARILY OVER SOUTHERN NORTH DAKOTA.
SUNDAY INTO MONDAY...AFOREMENTIONED UPPER LOW CONTINUES ITS
SOUTHERLY SLIDE TOWARDS NORTHERN MINNESOTA/LAKE SUPERIOR. MODELS
CONTINUE TO BE IN PRETTY GOOD AGREEMENT WITH THE TRACK OF THIS
SYSTEM. COOLER AIRMASS SWINGING AROUND THE LOW WILL PUSH INTO THE
AREA...WITH THE MAIN PUSH COMING LATE SUNDAY INTO MONDAY. THIS WILL
BRING WELL BELOW AVERAGE TEMPS TO THE REGION EARLY NEXT WEEK...WITH
MOST LOCATIONS SEEING HIGHS AROUND 15 TO 20 DEGREES BELOW AVERAGE ON
MONDAY. WILL HAVE TO WATCH THE TREND WITH THIS AS TEMPS MAY NEED TO
BE LOWERED EVEN FURTHER. A FEW SHOWERS WILL BE POSSIBLE ON MONDAY AS
VARIETY OF WAVES WRAP THROUGH CYCLONIC FLOW...PARTICULARLY FROM THE
TURTLE MOUNTAINS TO THE JAMES RIVER VALLEY.
FOR THE REMAINDER OF THE EXTENDED...UPPER LOW MOVES OFF TO THE EAST
WHILE RIDGE OVER THE WESTERN CONUS KEEPS NORTHWEST FLOW OVER OUR
AREA KEEPING CONDITIONS MAINLY DRY. TEMPERATURES WILL WARM THROUGH
MID-WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1210 PM CDT FRI JUL 11 2014
VFR CIGS/VSBYS EXPECTED THROUGH THE PERIOD. EXPECT ISOLATED SHOWERS
AND THUNDERSTORMS THROUGH 00Z SATURDAY AT KDIK. THERE WILL BE A
RENEWED THREAT FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS
AT KDIK MAINLY AFTER 05Z SATURDAY. THIS MAY REACH KBIS AND HENCE A
VCSH IS IN THE OVERNIGHT PERIOD FORECAST.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...NH
LONG TERM...JJS
AVIATION...KS
AREA FORECAST DISCUSSION
NWS PORTLAND OR
241 PM PDT FRI JUL 11 2014
.SYNOPSIS...MOIST AND UNSTABLE SOUTH FLOW ALOFT WILL CONTINUE TO
SPREAD INTO THE AREA TONIGHT. THIS WILL RESULT IN THE THREAT OF
THUNDERSTORMS TO THE CASCADES AND POSSIBLY AS FAR WEST AS THE COAST
RANGE BY LATE THIS EVENING. AN UPPER LOW OFF THE NORTH CALIFORNIA
COAST SATURDAY IS EXPECTED TO MOVE NORTH TO NORTHEAST AND INLAND INTO
EXTREME SW OREGON SUNDAY FOR ANOTHER THREAT OF THUNDERSTORMS...
EXTENDING FROM THE COAST RANGE...THE VALLEYS AND TO THE CASCADES.
WELL-ABOVE NORMAL DAYTIME TEMPERATURES CAN BE EXPECTED THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.SHORT TERM...TONIGHT THROUGH MONDAY...PRIMARY FORECAST CHALLENGES
REMAIN THE THUNDERSTORM POTENTIAL THROUGH TONIGHT AND AGAIN SUNDAY.
VISIBLE AND INFRA-RED SATELLITE IMAGERY SHOW MID AND HIGH-LEVEL
MOISTURE CONTINUNING TO STREAM N INTO THE AREA FROM SWRN OREGON. IR
LOOP INDICATED THE COLDEST TOPPPED CLOUDS IN DOUGLAS COUNTY AND
EXTREME SERN LANE COUNTY. LOCAL LIGHTNING DETECTION PRODUCT AS OF 20Z
NOT SHOWING ANYMORE LIGHTNING. WATER VAPOR IMAGERY SHOWS THE PRIMARY
CIRCULATION CENTER NEAR 40N 129W GRADUALLY DRIFTING NW. THERE MAY BE
A SECONDARY SUBTLE SHORT-WAVE NEAR KBOK. STILL... DEFORMATION AXIS
OVER SRN AND CENTRAL OREGON AS SEEN IN WATER VAPOR CONTINUES TO
MIGRATE NWD THIS AFTERNOON. NAM AND GFS MODEL SOUNDINGS FOR VARIOUS
LOCATIONS IN THE WILLAMETTE VALLEY NOT AT ALL IMPRESSIVE REGARDING
CONVECTION. MAIN INHIBITING FACTOR SEEMS TO BE CONVECTIVE INHIBITION
OR CIN AND THE HIGH CONVECTIVE TRIGGER TEMPS. 12Z NAM VALID 03Z SAT
SHOWED THE HIGHEST 700 MB THETA-E AIR GENEALLY S OF A FLORENCE TO
EUGENE LINE. ALSO...700 MB EAST FLOW WILL TEND TO PUSH THE BEST
DYNAMICS FURTHER AWAY FROM THE AREA. THE 18Z HRRR ALSO NOT VERY
SUPPORTIVE OF CONVECTION IN THE CWA. AT 23Z IT DEPICTS AN AREA OF
35-45 DBZ ECHOES IN CENTRAL AND WRN DOUGLAS COUNTY...BUT BY 02Z SAT
REFLECTIVITY COVERAGE QUICKLY DIMINISHES WITH JUST WEAK RETURNS OFF
THE CENTRAL COAST AND ANOTHER AREA IN ERN LANE COUNTY. WILL LEAVE
CURRENT THUNDERSTORM FORECAST FOR TONIGHT ALONE BUT WOULD NOT BE
SURPRISED IF VERY LITTLE LIGHTNING OCCURRED.
SATURDAY LOOKS TO BE AN IN-BETWEEN DAY AS A TRANSITORY 500 MB RIDGE
MOVES OVER THE AREA IN THE WAKE OF TONIGHTS SHORT-WAVE. MODEL
SOUNDINGS FOR SAT AFTERNOON...PARTICULARLY THE GFS...ARE SOMEWHAT
DRY...POSSIBLY INDICATING DECENT SUBSIDENCE BEHIND THE DEPARTING
SYSTEM...BUT MORE LIKELY THAT THE AIR MASS WILL BE SO WARM AND CAN
HOLD MUCH MORE MOISTURE THAN AN AIR MASS UNDER SEASONAL CONDITIONS.
MAIN ISSUE SATURDAY WILL BE THE RISING 850 MB TEMPS...CLIMBING TO
AROUND 22C OVER KPDX. THIS WILL BE THE START OF A MULTI-DAY HOT
SPELL. WILL ISSUE A HEAT ADVISORY FOR THIS EPISODE. HAVE KEPT ANY
THUNDERSTORM MENTION SAT TO THE CASCADES WHERE MID-LEVEL LAPSE RATES
CLOSE TO 8C/KM ARE FORECAST BY THE GFS MODEL SOUNDING.
SUNDAY LOOKS TO BE QUITE INTERESTING. ANOTHER ROUND OF MOIST SOUTH
FLOW ALOFT BEGINS TO SPREAD INTO SWRN OREGON AS EARLY AS SAT EVENING.
GFS AND ECMWF SIMILAR WITH THE OVERALL DETAILS...BUT THE 12Z NAM
APPEARS TO BE AN OUTLIER. THE 12Z ECMWF AND 12Z GFS BRING THE NEXT
LOW CENTER TO NEAR 41N 129W BY 12Z SUN. THE NAM IS A LITTLE MORE SW
WITH THE FEATURE AND MUCH SLOWER MOVING IT THROUGH THE FORECAST AREA.
UNLIKE TODAYS SYSTEM...THIS NEXT ONE IS EXPECTED TO
HAVE JET SUPPORT. GFS AND ECMWF SHOW A 60-80 KT 300 MB JET SEGMENT
MOVING INTO SWRN OREGON SUN MORNING. FORECAST AREA WILL BE IN THE
FAVORED QUADRANT OF THE JET SEGMENT FOR ADDITIONAL CONVECTIVE
SUPPORT. GFS MODEL SOUNDINGS FOR KPDX AND FOR A POINT IN THE N OREGON
CASCADES VALID SUN AFTERNOON ARE QUITE IMPRESSIVE. THE KPDX SOUNDING
VALID 00Z MON HAS A SURFACE-BASED CAPE OF NEARLY 600 J/KG...LIFTED
INDEX OF -2...TOTAL TOTALS OF 51 AND PRECIPITABLE WATER OF 1.37
INCHES. THE CASCADE SOUNDING IS EVEN MORE IMPRESSIVE WITH A CAPE OF
OVER 900 J/KG...LI OF -4...TOTAL TOTALS OF 54...0-6KM BULK SHEAR OF
NEARLY 40 KT...PRECIPITABLE WATER 1.66 INCHES...AND A SWEAT INDEX OF
311 (WE USE 250 AS THE BENCHMARK FOR POSSIBLE SEVERE). THE SREF
CALIBRATED PROBABILITY OF THUNDERSTORMS VALID 00Z-03Z MON SHOWS A 50
PERCENT BULLS-EYE OVER THE CASCADES AND THE 30 PERCENT CONTOUR TO THE
COAST. ALL IN ALL...MODELS ARE SHOWING SEVERAL INGREDIENTS COMING
TOGETHER FOR A CLASSIC PAC NW THUNDERSTORM EVENT. THUNDERSTORM
ACTIVITY SHOULD CONTINUE THROUGH SUN NIGHT...ESPECIALLY IN THE NERN
ZONES. WILL ALSO TONE DOWN SUN MAX TEMPS AS THERE SHOULD BE EXTENSIVE
CLOUD COVER DESPITE 850 MB FORECAST TEMPS OF 21-23C.
WOULD EXPECT A FLOOD OF MARINE AIR SUN NIGHT AND MON MORNING BEHIND
THE DEPARTING SHORT-WAVE. THIS WILL QUICKLY STABILIZE THINGS SUCH
THAT BY MON AFTERNOON ANY CONVECTION SHOULD BE WELL EAST OF THE AREA.
850 TEMPS 00Z TUE TO REMAIN IN THE 21-23C RANGE AND A 1000-500 MB
THICKNESS RIDGE NEAR THE OREGON COAST RANGE. WEISHAAR
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MAIN EMPHASIS WILL BE ON
THE UNSEASONABLY HOT CONDITIONS THROUGH MUCH OF THE PERIOD. 12Z ECMWF
MAINTAINS THE HOT PATTERN THROUGH AT LEAST WED. IT DOES HINT AT THE
POSSIBILITY OF A LITTLE MARINE AIR SEEPAGE BEGINNING WEDNESDAY...BUT
MORE SO ON THURSDAY. DO NOT AGREE WITH THE GFS SOLUTION OF HAVING A
DEEP UPPER LOW SWING THROUGH LATE IN THE WEEK. 12Z ECMWF KEEPS THE
AREA IN NWLY FLOW ALOFT AND ONSHORE LOW-LEVEL FLOW...KEEPING DAYTIME
TEMPERATURES SLIGHTLY ABOVE AVERAGE. A PRIMARY CONCERN WILL BE THE
HIGH DEW POINTS...RESULTING IN UNCOMFORTABLE NIGHTTIME PERIODS.
WEISHAAR
&&
.AVIATION...MARINE STRATUS REMAINS ALONG THE COASTLINE WITH IFR
AND LOCAL LIFR CIGS AND VIS THIS AFTERNOON. SOME AREAS WILL CLEAR
TO THE COASTLINE BUT EXPECT STRATUS TO MOVE BACK IN TO THE COAST
RANGE EARLY THIS EVENING WITH EXTENSIVE IFR AND LIFR TONIGHT. NOT
MUCH CHANGE FOR TOMORROW ALONG THE COAST. INLAND AREAS WILL REMAIN
VFR WITH THE MAIN THREAT BEING THE MID LEVEL MOISTURE MOVING UP FROM
THE SOUTH ASSOCIATED WITH THE DISTURBANCE ALOFT OVER SOUTHERN
OREGON. CIGS WILL BE 8000 TO 12000 FEET TONIGHT WITH SOME ISOLATED
SHOWERS MOSTLY ALOFT DURING THE EVENING IN THE SOUTH SPREADING
NORTH. THERE IS A SLIGHT CHANCE OF ELEVATED THUNDERSTORMS FROM
KSXT TO KCVO 23Z-04Z...INCLUDING THE ADJACENT COAST RANGE AND
CASCADES. THERE REMAINS A POSSIBILITY OF SOME ELEVATED
THUNDERSTORMS SPREADING NORTH KCVO-KPDX DURING THE EVENING 03Z-
09Z. SCHNEIDER
KPDX AND APPROACHES...VFR TODAY AND TONIGHT. THERE WILL BE A 15
PERCENT CHANCE OF A THUNDERSTORM AFTER 03Z AND LIKELY A LOT OF MID
LEVEL CLOUDS WITH A FEW SHOWERS MOSTLY ALOFT FROM 03Z-09Z AS DEBRIS
FROM STORMS ELSEWHERE MOVES OVER THE AREA. STRATUS IS NOT EXPECTED
TO REACH THE TERMINAL SATURDAY MORNING. SCHNEIDER
&&
.MARINE...HIGH PRES WILL REMAIN OVER THE NE PAC THROUGH THE
WEEKEND...KEEPING WINDS FROM THE N TO NW. THE GRADIENTS WILL
CONTINUE TO BE WEAK FOR LIGHTER WINDS TONIGHT THROUGH SATURDAY
NIGHT. THE OFFSHORE HIGH AND THE INLAND THERMAL LOW WILL
STRENGTHEN SUNDAY FOR INCREASING NORTHWEST WINDS BY AFTERNOON AND
LIKELY REACH SMALL CRAFT ADVISORY LEVELS...THEN REMAIN BRISK INTO
THE MIDDLE OF NEXT WEEK.
SEAS CONTINUE TO FALL TONIGHT AND SATURDAY. BY SATURDAY AFTERNOON
THE NORTHWEST FRESH SWELL ABATES UNDER LIGHT WINDS AND THE ENP
MODEL INDICATES WE WILL START TO SEE A LONG PERIOD WEST SWELL OF 2
TO 3 FT. THIS WOULD NORMALLY BE MASKED BY THE NORTHWEST WIND
SEAS. ALL IN ALL THE SEAS WILL REMAIN BELOW 5 FT UNTIL THE
NORTHWESTERLY INCREASE SUNDAY AFTERNOON. THE COLUMBIA BAR WILL
SEE A VERY STRONG EBB EARLY SATURDAY MORNING BUT WITH RELATIVELY
LIGHT INCOMING SWELL WAVES WILL REMAIN BELOW SMALL CRAFT
LEVELS...STILL MARINERS SHOULD BE CAUTIOUS CROSS THE BARS DURING
THIS VERY STRONG EBB. SCHNEIDER
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HEAT ADVISORY FROM 5 AM SATURDAY TO 2 PM PDT TUESDAY FOR
CASCADE FOOTHILLS IN LANE COUNTY-CASCADES IN LANE
COUNTY-CENTRAL COAST RANGE OF WESTERN OREGON-CENTRAL COLUMBIA
RIVER GORGE-CENTRAL WILLAMETTE VALLEY-COAST RANGE OF NORTHWEST
OREGON-GREATER PORTLAND METRO AREA-LOWER COLUMBIA-NORTHERN
OREGON CASCADE FOOTHILLS-NORTHERN OREGON CASCADES-SOUTH
WILLAMETTE VALLEY-UPPER HOOD RIVER VALLEY-WESTERN COLUMBIA
RIVER GORGE.
WA...HEAT ADVISORY FROM 5 AM SATURDAY TO 2 PM PDT TUESDAY FOR
CENTRAL COLUMBIA RIVER GORGE-GREATER VANCOUVER AREA-I-5
CORRIDOR IN COWLITZ COUNTY-SOUTH WASHINGTON CASCADE
FOOTHILLS-SOUTH WASHINGTON CASCADES-WESTERN COLUMBIA RIVER
GORGE-WILLAPA HILLS.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
942 AM PDT FRI JUL 11 2014
.SYNOPSIS...MOIST AND UNSTABLE SOUTH FLOW ALOFT WILL SPREAD INTO THE
AREA TODAY AND TONIGHT. THIS BRINGS THE THREAT OF THUNDERSTORMS TO
THE CASCADES AND POSSIBLY AS FAR WEST AS THE COAST RANGE BY LATER
THIS EVENING. AN UPPER LOW OFF THE NORTH CALIFORNIA COAST SATURDAY IS
EXPECTED TO MOVE NORTH TO NORTHEAST AND INLAND INTO EXTREME SW OREGON
SUNDAY FOR ANOTHER THREAT OF THUNDERSTORMS...EXTENDING FROM THE COAST
RANGE...THE VALLEYS AND TO THE CASCADES. WELL-ABOVE NORMAL DAYTIME
TEMPERATURES CAN BE EXPECTED FRIDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.SHORT TERM...TODAY THROUGH SUNDAY...PRIMARY FORECAST CHALLENGES WILL
BE THUNDERSTORM POTENTIAL THIS AFTERNOON THROUGH TONIGHT AND AGAIN
SUNDAY. MORNING VISIBLE SATELLITE IMAGERY SHOWS THE MARINE STRATUS
CONFINED TO THE COAST AND MAJOR COASTAL RIVER DRAINAGES AND ALONG THE
COLUMBIA RIVER TO NEAR KPDX. MID AND HIGH LEVEL CLOUDS SPREADING
NORTH INTO SRN DOUGLAS COUNTY ASSOCIATED WITH AN UPPER LEVEL
DISTURBANCE NEAR 40N 129W. WATER VAPOR IMAGERY SHOWS SELY DIFFLUENT
FLOW ALOFT INTO SWRN OREGON THIS MORNING. ALTHOUGH THE ACTUAL LOW
CENTER IS WELL OFF THE COAST...THE DIFFLUENT FLOW AND ASSOCIATED
DEFORMATION AREA HAS ALLOWED THE AIR MASS TO BECOME MORE MOIST.
MAIN CONCERN TODAY CONTINUES TO BE THE CONVECTIVE THREAT. AREAS SOUTH
OF AN ALBANY-NEWPORT LINE STAND THE BEST CHANCE OF THUNDERSTORMS.
LATEST NAM MODEL RUN SHOWS A VORTICITY LOBE ROTATING INTO THE FAR S
PART OF THE FORECAST AREA MID TO LATE AFTERNOON. HIGHEST 700 MB THETA
E AIR OFF THE NAM VALID 21Z IS CONFINED TO AREAS SOUTH OF SRN LANE
COUNTY. AM A LITTLE CONCERNED THAT THE BEST DYNAMICS WILL BE PUSHED
TO THE CENTRAL OREGON COASTLINE BY LATE AFTERNOON AND EARLY EVENING
DUE TO EAST 700 MB FLOW...THUS REDUCING THE CONVECTIVE THREAT FURTHER
NORTH. THE 10Z HRRR RUN SHOWS THE LEADING EDGE OF THE 30 DBZ
REFLECTIVITY SHIELD TO BE IN CENTRAL LANE COUNTY AT 00Z SAT. OPTED TO
MENTION SLIGHT CHANCE OF TS FURTHER WEST IN THE CENTRAL OREGON COAST
RANGE THIS AFTERNOON AND INTO ALL OF THE COAST RANGE 00Z-06Z SAT. NAM
AND NAMM MODEL SOUNDINGS FOR KEUG VIA BUFKIT NOT ALL THAT IMPRESSIVE
FOR CONVECTION. AT 02Z NAMM MODEL SOUNDING SHOWING MINIMAL
SURFACE-BASED CONVECTIVE AVAILABLE POTENTIAL ENERGY (CAPE) WITH OVER
300 J/KG CONVECTION INHIBITION (CIN) TO OVERCOME. HOWEVER...LIFTED
INDICES LOWER TO NEAR 0 WITH MODEL PRECIPITABLE WATER UP TO 1.3
INCHES. THIS SHORT-WAVE DOES NOT APPEAR TO HAVE MUCH...IF ANY...JET
SUPPORT. FEEL THAT OVERALL CONVECTIVE THREAT WILL WANE PRETTY QUICKLY
AFTER 06Z AS THE MAIN CIRCULATION CENTER CONTINUES TO DRIFT NW-N.
SATURDAY LOOKS TO BE AN IN-BETWEEN DAY AS A TRANSITORY 500 MB RIDGE
MOVES OVER THE AREA IN THE WAKE OF TONIGHTS SHORT-WAVE. MODEL
SOUNDINGS FOR SAT AFTERNOON...PARTICULARLY THE GFS...ARE SOMEWHAT
DRY...POSSIBLY INDICATING DECENT SUBSIDENCE BEHIND THE DEPARTING
SYSTEM...BUT MORE LIKELY THAT THE AIR MASS WILL BE SO WARM AND CAN
HOLD MUCH MORE MOISTURE THAN AN AIR MASS UNDER SEASONAL CONDITIONS.
MAIN ISSUE SATURDAY WILL BE THE RISING 850 MB TEMPS...CLIMBING TO
AROUND 22C OVER KPDX. THIS WILL BE THE START OF A MULTI-DAY HOT
SPELL. KEPT ANY THUNDERSTORM MENTION SAT TO THE CASCADES WHERE
MID-LEVEL LAPSE RATES CLOSE TO 8C/KM ARE FORECAST BY THE GFS MODEL
SOUNDING.
SUNDAY CONTINUES TO LOOK MORE AND MORE INTERESTING. ANOTHER ROUND OF
MOIST SOUTH FLOW ALOFT BEGINS TO SPREAD INTO SWRN OREGON AS EARLY AS
SAT EVENING. MODELS STARTING TO CONVERGE ON A GENERAL SOLUTION. THE
12Z NAM...00Z ECMWF AND 06Z GFS BRING THE NEXT LOW CENTER TO NEAR 41N
129W BY 12Z SUN. UNLIKE TODAYS SYSTEM...THIS NEXT ONE IS EXPECTED TO
HAVE JET SUPPORT. NAM AND ECMWF SHOW A 60-80 KT 300 MB JET SEGMENT
MOVING INTO SWRN OREGON SUN MORNING. FORECAST AREA WILL BE IN THE
FAVORED QUADRANT OF THE JET SEGMENT FOR ADDITIONAL CONVECTIVE
SUPPORT. NAM MODEL SOUNDINGS FOR KPDX VALID SUN AFTERNOON ARE QUITE
IMPRESSIVE. BY 23Z THE MODEL SOUNDING SHOWS OVER 1500 J/KG CAPE...LI
OF -3 AND AN EQUILIBRIUM LEVEL IN EXCESS OF 37000 FEET. STORM
PREDICTION CENTER (SPC) EVEN MENTIONS THE POSSIBILITY OF A FEW STORMS
APPROACHING SEVERE LIMITS. NAM MODEL SOUNDINGS FOR THE CASCADES ARE
EVEN MORE IMPRESSIVE...WITH TOTAL TOTALS IN EXCESS OF 50...SWEAT
INDEX OVER 250 (THE NORMAL BENCHMARK WE USE FOR POSSIBLE SEVERE
WEATHER) AND 0-6KM BULK SHEAR VALUES OF 30-35 KTS. THUNDERSTORM
ACTIVITY SHOULD CONTINUE THROUGH SUN NIGHT...ESPECIALLY IN THE NERN
ZONES. WILL ALSO TONE DOWN SUN MAX TEMPS AS THERE SHOULD BE EXTENSIVE
CLOUD COVER DESPITE 850 MB FORECAST TEMPS OF 21-23C. WEISHAAR
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...MAIN EMPHASIS WILL BE ON
THE UNSEASONABLY HOT CONDITIONS THROUGH MUCH OF THE PERIOD. LATEST
GFS HAS COME AROUND TO THE 00Z ECMWF IDEA OF A NOT SO OMINOUS HEAT
WAVE. STILL...EXPECT INLAND MAX TEMPS IN THE 90S MON THROUGH AT LEAST
WED. 00Z FRI MEX GUIDANCE GIVES KPDX A MAX OF 95 MON AND
TUE...INSTEAD OF THE 100 IT SHOWED YESTERDAY. THE BIGGER CONCERN WILL
BE THE HIGH DEW POINTS...RESULTING IN UNCOMFORTABLE NIGHTTIME
PERIODS. HOT SPELLS BEYOND 3-4 DAYS ARE RARE. WILL BE LIKELY GOING
WITH AN EXCESSIVE HEAT ADVISORY SAT-WED FOR THE AFTERNOON FORECAST
PACKAGE. THERE MAY BE SLIGHT RELIEF BEGINNING AROUND WED...BUT MAX
TEMPS WILL REMAIN SEVERAL DEGREES ABOVE NORMAL. WEISHAAR
&&
.AVIATION...MARINE INVERSION ABOUT 2000 FEET DEEP ALONG THE COAST
THIS MORNING WITH LIGHT NW FLOW KEEPING THE IFR AND LIFR STRATUS
PACKED INTO THE BASES OF THE COAST RANGE. EXPECT A LATE BREAKOUT
IN MOST COASTAL AREAS 20-23Z AND THEN IFR CONDITIONS RETURNING
AFTER ABOUT 03Z. INLAND THERE HAS BEEN STRATUS THAT MOVED DOWN THE
COLUMBIA RIVER TO KPDX THIS MORNING BUT THIS WILL DISSIPATE
RAPIDLY. A WEATHER DISTURBANCE IS ROTATING UP AROUND A LOW
OFFSHORE AND WILL MOVE ACROSS THE AREA THIS AFTERNOON AND TONIGHT.
THIS WILL RESULT IN MID AND LEVEL MOISTURE INCREASE AND SCATTERED
THUNDERSTORMS OVER THE MOUNTAINS. THE 700MB FLOW BECOMES SOUTH
THIS AFTERNOON AND THEN SOUTHEAST DURING THE EVENING AND EXPECT A
FEW THUNDERSTORMS WILL DRIFT OUT OVER THE WILLAMETTE VALLEY. THE
HIGHER THREAT IS IN THE SOUTHERN WILLAMETTE VALLEY. EXPECT
THUNDERSTORMS TO BE RELATIVELY HIGH BASED. SCHNEIDER
KPDX AND APPROACHES...VFR TODAY AND TONIGHT. THERE WILL BE A 15
PERCENT CHANCE OF A THUNDERSTORM AFTER 00Z AND LIKELY A LOT OF MID
LEVEL CLOUDS FROM 03Z-09Z AS DEBRIS FROM STORMS ELSEWHERE MOVES OVER
THE AREA. SCHNEIDER
&&
.MARINE...HIGH PRES WILL REMAIN OVER THE NE PAC THROUGH THE
WEEKEND...KEEPING WINDS FROM THE N TO NW. THE GRADIENTS WILL BE
WEAKER TODAY AND SATURDAY FOR WEAKER WINDS THAN THE LAST COUPLE OF
DAYS. THE MODELS INDICATE THE NORTH TO NORTHWEST WINDS WILL THEN
STRENGTHEN SUNDAY AND POSSIBLY REACH SMALL CRAFT ADVISORY
LEVELS...THEN REMAIN BRISK INTO THE MIDDLE OF NEXT WEEK.
SEAS ARE NOW FALLING...CURRENTLY AT AROUND 6 FT AND WILL CONTINUE
TO FALL TODAY. THIS WILL ALSO REDUCE THE WAVES ON THE COLUMBIA
RIVER BAR...BUT THERE IS A VERY STRONG EBB TOMORROW MORNING AND
THAT WILL RESULT IN BREAKERS. CONDITIONS SHOULD STAY JUST BELOW
SMALL CRAFT ADVISORY CATEGORY BUT BOATERS SHOULD REMAIN CAUTIOUS
DURING THE EBB. SEAS WILL LIKELY BUILD AGAIN IN THE INCREASING
NORTHWEST WINDS LATER SUNDAY AND MONDAY. SCHNEIDER
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS MEDFORD OR
920 AM PDT FRI JUL 11 2014
.DISCUSSION...THE FIRST ROUND OF CONVECTION IS MOVING THROUGH THE
REGION THIS MORNING AS A STRONG SHORT WAVES CYCLES THROUGH FROM THE
SOUTH. WITH THE INCREASED CLOUD COVER HAVE LOWERED HIGH TEMPERATURES
FOR TODAY. THERE ARE SEVERAL MORE SHORT WAVES THAT WILL MOVE THROUGH
AND THE BIGGEST CONCERN WILL BE HOW MUCH INSTABILITY IS MAXED OUT
WITH THE FIRST LINE OF CONVECTION AND ITS EFFECTS ON LATER
THUNDERSTORM DEVELOPMENT. WILL STICK WITH THE CURRENT FORECAST ON
THE THUNDERSTORMS AT THIS TIME. SVEN
PREVIOUS DISCUSSION...VERY WARM TEMPERATURES WILL CONTINUE INTO THE
WEEKEND AS THE UPPER LEVEL RIDGE WILL ONLY WEAKEN TEMPORARILY. A
LOW PRESSURE TROUGH APPROACHING NORTHERN CALIFORNIA COAST THIS
MORNING WILL SEND A BAND OF MOISTURE INTO OUR FORECAST AREA ALONG
WITH AREAS OF INSTABILITY. SO FAR THERE HAVE BEEN CLOUD TO CLOUD
LIGHTNING STRIKES JUST SOUTH OF SISKIYOU COUNTY OVERNIGHT.
MOISTURE IS EXPECTED TO SPREAD INTO EASTERN SISKIYOU COUNTY MAINLY
FROM THE CASCADES EASTWARD AROUND DAY BREAK. THE NAM12 TAKES MOST
OF THIS MOISTURE NORTH ALONG AND JUST EAST OF THE CASCADES WITH
ANOTHER BAND OF MOISTURE ROTATING BACK ACROSS SW OREGON. THE SHORT
TERM HRRR MODEL SHOWS A SIMILAR TRACK ON FORECAST RADAR RETURN BUT
SHOWS A MODERATE RETURN (30-40DBZ) EXPANDING BACK INTO NW JACKSON
COUNTY AND EASTERN DOUGLAS COUNTY INTO FIRE ZONE 617 BY THIS
AFTERNOON. THE NAM12 SHOWS MORE INSTABILITY FURTHER WEST INTO
JOSEPHINE AND JACKSON COUNTY WHERES THE GFS KEEPS NEGATIVE LIFTED
INDEX MAINLY NEAR THE CASCADES WHILE ERODING ANY CAPPING BY MID
MORNING. MY FEELING ON THIS IS THAT WE MAY SEE TWO DISTINCT BAND
OF CONVECTION, ONE TRAVELLING NORTH INTO THE KLAMATH BASIN AND THE
OTHER COMING UP THROUGH THE HAPPY CAMP DISTRICT INTO THE ILLINOIS
VALLEY AND THEN NORTHWARD INTO THE UMPQUA BASIN. CURRENT RED FLAG
WARNING COVERS THIS TREND AND WILL KEEP AREAL COVERAGE AS IS. BOTH
MODELS SHOW CLEARING ACROSS THE WEST SIDE THIS AFTERNOON AND THIS
MAY BE CONDUCIVE TO THE SECOND ROUND OF CONVECTION FROM SURFACE
HEATING.
FOR SATURDAY..THERE WILL BE MORE H7-H5 MOISTURE EAST OF THE
CASCADES AND THIS IS WHERE MOST CONVECTION WILL BE LOCATED. THE
AIR MASS WILL BE MUCH DRIER WEST OF THE CASCADES. HAVE KEPT ALL OF
THUNDERSTORMS FORECAST TO THE EAST OF THE CASCADES.
ON SUNDAY..ANOTHER ROUND OF TROUGH WILL APPROACH THE COAST AGAIN.
ONE THING THAT MAKES THIS TROUGH DIFFERENT IS THE PRESENCE OF 75KT
JETMAX MOVING INTO NW CALIFORNIA AND SW OREGON. IN ADDITION BOTH
MODELS INDICATE ENOUGH MOISTURE TO GENERATE THUNDERSTORMS. /FB
&&
.AVIATION...BASED ON THE 11/06Z TAFS...IFR CONDITIONS
ARE PRESENT ALONG THE COAST AND ARE EXPECTED TO PERSIST THROUGH
EARLY THIS MORNING...WITH CLEARING IN THE LATE FRIDAY MORNING.
ELSEWHERE...EXPECT MAINLY VFR CONDITIONS EARLY THIS MORNING THEN AS
THUNDERSTORMS DEVELOP MAY SEE LOCAL MVFR CIGS DEVELOP DURING THE DAY
WITH A RETURN TO VFR DURING THE EVENING. THUNDERSTORMS WILL HAVE
THE LARGEST IMPACT ON INLAND AREAS TODAY. THUNDERSTORMS WILL AFFECT
NORTHERN CALIFORNIA FIRST EARLY THIS MORNING...AND THEN SPREAD INTO
SOUTHERN OREGON DURING THE MORNING AND CONTINUING INTO THE
AFTERNOON. GREATEST COVERAGE OF THUNDERSTORMS EXPECTED
LATE IN THE MORNING INTO THE AFTERNOON. VERY GUSTY WINDS AND HAIL
ARE EXPECTED WITH SOME OF THESE STORMS. /CC
&&
.MARINE...UPDATED THURSDAY 11 JULY 300 AM PDT...WINDS HAVE
WEAKENED CONSIDERABLY...AND SEAS WILL GRADUALLY DIMINISH THROUGH
TODAY. SEAS ARE COMING DOWN A BIT SLOWER THAN PREVIOUSLY
FORECAST...SO HAVE EXTENDED THE SMALL CRAFT ADVISORY OUT A FEW MORE
HOURS. A WEAK LOW PRESSURE WILL MOVE THROUGH THE WATERS TODAY INTO
TOMORROW...BUT WINDS WILL REMAIN GENERALLY LIGHT UNTIL SUNDAY
AFTERNOON. THE THERMAL TROUGH PATTERN WILL REDEVELOP SUNDAY AND
STRENGTHEN MONDAY...RESULTING IN ANOTHER ROUND OF MODERATE TO
STRONG NORTH WINDS AND BUILDING SHORT PERIOD SEAS. -BPN
&&
.FIRE WEATHER...SATELLITE AND RADAR IMAGERY TO THE SOUTH SHOW SOME
CONVECTION HAS BEGUN IN ASSOCIATION WITH A SHORT WAVE AND MONSOONAL
MOISTURE THAT WILL BE MOVING INTO OUR AREA LATER THIS MORNING
THROUGH THIS AFTERNOON. SOME CLOUD-TO-CLOUD LIGHTNING HAS ALSO BEEN
DEPICTED WITH THESE BUILDUPS...SUGGESTING THAT A GOOD DEAL OF
INSTABILITY EXISTS OVER THE AREA THIS MORNING EVEN BEFORE SOLAR
HEATING BEGINS. MUCH DEPENDS ON THE TIMING OF THE SHORTWAVE AND THE
ARRIVAL OF MOISTURE...AS WELL AS WHAT AREAS RECEIVE THE MOST
HEATING...AND THE EXACT LOCATION OF JET ENERGY OVERHEAD WHICH COULD
LEND TO MORE NUMEROUS CELLS. STEERING WINDS ARE EXPECTED TO BE FROM
THE SOUTH AND SOUTHEAST WHICH IS A FAVORABLE FLOW TO GET STORMS TO
SPREAD OUT OVER THE VALLEYS WEST OF THE CASCADES. GIVEN THE DRY
FUELS AND EXPECTED NUMEROUS LIGHTNING STRIKES EXPECTED...HAVE
CONTINUED RED FLAG WARNINGS FOR NORTHERN CAL AND MOST OF OREGON
ZONES. THE EXCEPTION WILL BE THE COASTAL ZONES...WHERE THE
ATMOSPHERE SHOULD REMAIN MUCH MORE STABLE. EVEN THEN...CAN NOT RULE
OUT ISOLATED THUNDERSTORMS FOR FIRE ZONES 615 AND 618. MODELS
SUGGEST THE BULK OF THE ACTION WILL SHIFT NORTH DURING THE DAY TODAY
AND COULD BE OUT OF THE AREA BY THIS AFTERNOON...BUT AGAIN MUCH
DEPENDS ON THE TIMING. ANOTHER UPPER LOW WILL MOVE TOWARDS THE AREA
SUNDAY, BUT THE MODELS SUGGEST MOST OF THE INSTABILITY AND
THUNDERSTORM POTENTIAL WILL BE FROM AROUND CRATER LAKE NORTH. -BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR ORZ624-625.
RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR
ORZ616-617-619>623.
CA...RED FLAG WARNING UNTIL 6 PM PDT THIS EVENING FOR
CAZ280>282-284-285.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS
UNTIL 11 AM PDT THIS
MORNING FOR PZZ350-356-370-376.
$$
FJB/FJB/CC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1250 PM CDT FRI JUL 11 2014
.UPDATE...
ISSUED AT 844 AM CDT FRI JUL 11 2014
FORECAST HAS BEEN UPDATED TO RAISE POPS CONSIDERABLY THROUGH THE
MORNING HOURS AS THE REMNANTS OF AN OVERNIGHT CONVECTIVE SYSTEM
TRACK TO THE EAST THROUGH THE REGION...PARTICULARLY IN SOUTHEAST
MINNESOTA AND WESTERN WISCONSIN. INSTABILITY REMAINS FAIRLY
WEAK...SO ANY THUNDERSTORMS SHOULD REMAIN FAIRLY ISOLATED. NOT
SURE HOW MUCH ACTIVITY WILL REDEVELOP IN THE AFTERNOON AS THIS
FEATURE MOVES OFF TO THE EAST BY THIS AFTERNOON. TEMPERATURES WILL
REMAIN DOWN DUE TO THE CLOUD COVER AND RAIN THIS MORNING...BUT
COULD MAKE A BRIEF REBOUND IN THE LATE AFTERNOON HOURS...SO HAVE
ADJUSTED THAT PART OF THE FORECAST AS WELL. UPDATES COMING
SHORTLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN SHORT TERM CONCERN IS ON PRECIPITATION CHANCES TODAY.
CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE CENTRAL U.S....A WEAK RIDGE OVER MICHIGAN...
A SHORTWAVE TROUGH CROSSING MN WITH THE CORE NEAR DULUTH...A WEAK
SHORTWAVE CROSSING NEBRASKA...AND A DEEP UPPER TROUGH OVER SOUTH
CENTRAL CANADA. DPVA AHEAD OF THE MN SHORTWAVE TROUGH COMBINED WITH
850MB MOISTURE TRANSPORT SEEN BY STRONGER 850MB WINDS ON RADARS FROM
EASTERN SOUTH DAKOTA INTO NORTHERN MN HAS SUPPORTED SHOWERS AND
STORMS NORTH OF MINNEAPOLIS. THE NEBRASKA SHORTWAVE AND ANOTHER NOSE
OF 850MB MOISTURE TRANSPORT HAS SUPPORTED OTHER SHORTWAVES AND
STORMS FROM NEBRASKA INTO SIOUX FALLS AREA. THE FORECAST AREA
MEANWHILE HAS ONLY SEEN A FEW LIGHT SHOWERS WEST OF THE MS RIVER
STEMMING FROM ACCAS CLOUDS ON THE EASTERN EXTENT OF THE MOISTURE
TRANSPORT ZONE. THE AIRMASS OVER THE REGION HAS CERTAINLY BECOME
WARMER AND MORE MOIST OVER THE PAST 24 HOURS. 850MB TEMPS HAVE
CLIMBED TO 12-15C ACCORDING TO 00Z SOUNDINGS WITH 20-25C READINGS IN
THE DAKOTAS. MEANWHILE...PRECIPITABLE WATER VALUES ARE UP TO 1-1.5
INCHES WITH A 2 INCH MAXIMA NEAR SIOUX FALLS PER RAP AND GOES
DERIVED.
THE FORECAST FOR TODAY IS RADICALLY DRIER THAN WHAT IT LOOKED LIKE
24 HOURS AGO. MUCH OF THIS IS A FUNCTION OF THE 850MB MOISTURE
TRANSPORT BEING INCORRECT. INSTEAD OF THE NOSE COMING RIGHT AT THE
FORECAST AREA...ITS IN NORTHERN MN AND NEAR SIOUX FALLS.
ADDITIONALLY...THE SHORTWAVE TRACKING ACROSS MN IS MOVING FASTER
THAN EARLIER PROJECTIONS.
RE-ANALYZING TODAYS FORECAST. IT APPEARS THE SHOWERS AND STORMS
TAKING PLACE NORTH OF MINNEAPOLIS WILL PROGRESS TO THE EAST THIS
MORNING WITH THE CORE OF THE SHORTWAVE TROUGH...PERHAPS CLIPPING
TAYLOR COUNTY. TO THE WEST...REGARDING THE SHOWERS AND STORMS
CROSSING NEBRASKA AND SIOUX FALLS...THESE MAY MAKE IT INTO NORTHEAST
IOWA LATE IN THE MORNING PER HRRR AND 11.00Z GFS PROGS. HOWEVER...
THE 850MB MOISTURE TRANSPORT NOSE SUPPORTING THEM IS PROGGED TO
DRAMATICALLY WEAKEN IN ALL MODELS...SO ITS POSSIBLE THEY DIE BEFORE
REACHING NORTHEAST IOWA. THIS LEAVES REALLY THE ONLY OTHER THREAT OF
PRECIPITATION FOR THE MORNING BEING THIS ACCAS WHICH COULD SHOWER
HERE AND THERE ACROSS MUCH OF THE FORECAST AREA DURING THE MORNING.
HEADING INTO THE AFTERNOON...DESPITE THE FACT THAT THE HIGHER
PRECIPITABLE WATER ZONE OVER SIOUX FALLS AREA IS PROGGED TO SHIFT
EAST INTO THE AREA...THERES NO FORCING TO DO ANYTHING WITH THAT
MOISTURE. SURFACE BOUNDARY WISE...A COLD FRONT LOOKS TO EXTEND
SOUTHWEST TO NORTHEAST ACROSS MN WHILE A WARM FRONT IS ACROSS
NEBRASKA...BOTH BEING WEST OF THE AREA. ADDITIONALLY...500MB HEIGHTS
ARE RISING IN THE WAKE OF THE SHORTWAVE TROUGH TO PROVIDE
SUBSIDENCE. 11.00Z NAM/GFS/REGIONAL CANADIAN ARE ALL DRY AND HAVE
TRENDED THE FORECAST EVEN MORE IN THAT DIRECTION. ONLY THE 11.00Z
HIRES ARW HAS SOME ISOLATED DIURNAL CONVECTION SO KEPT A 20 PERCENT
CHANCE IN CASE. WITH A DRIER FORECAST AND 850MB TEMPS BETWEEN 14-16C
TODAY...HAVE RAISED TEMPERATURES A FEW DEGREES. PLENTY OF MID CLOUD
WILL HAMPER HIGHS FROM REACHING FULL POTENTIAL...THOUGH.
FOR TONIGHT...THERE IS GOOD MODEL AGREEMENT FOR 850MB MOISTURE
TRANSPORT TO INCREASE ACROSS THE CENTRAL PLAINS INTO THE I-80
CORRIDOR ACROSS NEBRASKA AND IOWA. THE CAUSE FOR THE INCREASE IS
TIED TO A FAIRLY STRONG MONSOONAL SHORTWAVE SEEN ON WATER VAPOR
IMAGERY OVER LAS VEGAS...ROTATING UP AROUND THE CENTRAL PLAINS RIDGE
INTO SOUTH DAKOTA BY 12Z SATURDAY. GIVEN THE HIGH PRECIPITABLE WATER
AIRMASS IN PLACE...IT SEEMS ALL BUT CERTAIN SHOWERS AND
THUNDERSTORMS WILL FIRE ON THE NOSE OF THAT 850MB MOISTURE TRANSPORT
ZONE. SOME OF THESE STORMS COULD WORK INTO LOCATIONS SOUTH OF
INTERSTATE 90 AFTER MIDNIGHT...THOUGH BELIEVE THE GREATER FOCUS FOR
THEM WILL OCCUR SOUTH AND WEST OF THE AREA PRIOR TO 12Z SATURDAY.
ALSO CANNOT RULE OUT A FEW SHOWERS AND STORMS THROUGH THE NIGHT
CROSSING TAYLOR/CLARK COUNTIES FROM THE COLD FRONT OVER MN TRACKING
THROUGH THERE. WITH A HIGH PRECIPITABLE WATER AIRMASS IN PLACE AND
MID CLOUD SPREADING IN FROM THE SOUTHWEST...ANTICIPATING A WARM
NIGHT. IN FACT...HIGHER DEWPOINTS ADVECTING IN COULD RESULT IN SOME
FOG.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 255 AM CDT FRI JUL 11 2014
MAIN LONG TERM CONCERNS ARE ON SEVERE WEATHER POTENTIAL SATURDAY
AFTERNOON/EVENING AND THE UNSEASONABLY COLD AIR MONDAY INTO TUESDAY.
SATURDAYS FOCUS IS ENTIRELY ON THE CURRENT MONSOONAL SHORTWAVE NEAR
LAS VEGAS. MODEL CONSENSUS BRINGS THIS SHORTWAVE THROUGH OUR AREA AT
ABOUT THE TIME OF PEAK HEATING. 0-6KM...0-3KM AND 0-1KM SHEAR VALUES
ALL REALLY INCREASE THROUGH THE DAY IN RESPONSE TO THE SHORTWAVE...
TOPPING OUT AT 21Z AROUND 60 KTS...45 KT AND 20-25 KT RESPECTIVELY.
THIS IS PLENTY FOR ORGANIZED SEVERE CONVECTION. THE DEEPER SHEAR IS
ALSO NICELY CYCLONICALLY CURVED. MEANWHILE...THE ATMOSPHERE IS
JUICED UP PRECIPITABLE WATER WISE WITH VALUES OF 2 INCHES GETTING
ADVECTED INTO THE AREA. ALSO GOOD MODEL CONSENSUS EXISTS FOR 750-
2000 J/KG OF MLCAPE TO BUILD UP SOUTH OF I-90...LIMITED BY PLENTIFUL
CLOUD COVER...WITH EVEN HIGHER VALUES BUILDING UP IN A CAPPED
AIRMASS NEAR I-80. THUS...SEE SOME CHANCE FOR A SEVERE WEATHER EVENT
SATURDAY AFTERNOON. HAIL THREAT IS LIMITED BY THE HIGH PRECIPITABLE
WATER AND WARM CLOUD DEPTHS AROUND 4 KM. THESE PARAMETERS INCREASE
THE HEAVY RAIN AND FLASH FLOODING CONCERN...HOWEVER...THE STRONG
SHEAR SHOULD PROMOTE PROGRESSIVE CONVECTION. ADDITIONALLY...THE
RECENT DRY PERIOD WILL ALLOW SOILS TO ABSORB MORE WATER. THE STRONG
SHEAR DEFINITELY MAKES DAMAGING WINDS A CONCERN. CANNOT RULE OUT A
TORNADO EITHER GIVEN THE 0-1KM SHEAR AND A WARM FRONT LIKELY TO SIT
NEAR/SOUTH OF US-20. REALLY THE ONLY ISSUE WITH SATURDAY AMONGST THE
MODELS IS THE PLACEMENT OF AFTERNOON CONVECTION. THE 11.00Z
NAM/REGIONAL CANADIAN ARE ALONG/NORTH OF I-90...WHICH BOTH HAVE HAD
A NORTHWARD BIAS TO SEVERE CONVECTIVE EVENTS THIS YEAR. PREFER THE
FARTHER SOUTH 11.00Z GFS/ECMWF/HIRES ARW. MUCH OF THE CONVECTION
SHOULD PUSH SOUTHEAST OF THE AREA BY 03Z WITH THE PASSAGE OF THE
SHORTWAVE...FOLLOWED BY SIGNIFICANT DRYING OF PRECIPITABLE WATER OF
NEARLY 1 INCH BY 12Z SUNDAY.
ON SUNDAY...THE DEEP UPPER TROUGH OVER SOUTH CENTRAL CANADA IS
PROGGED TO BEGIN ITS DESCENT INTO OUR REGION. A COLD FRONT AHEAD OF
THE TROUGH SHOULD DROP SOUTH THROUGH THE AREA...AGAIN AT THE TIME OF
PEAK HEATING. 0-6KM SHEAR IS RUNNING 40-50 KT WITH 0-3KM AT 25-35KT.
HOWEVER...INSTABILITY LOOKS TO BE SEVERELY LACKING RESULTING FROM THE
SIGNIFICANT DRYING OF PRECIPITABLE WATER SATURDAY NIGHT. 11.00Z GFS
HAS THE GREATEST INSTABILITY AT 500-1000 J/KG OF MLCAPE...BUT THINK
ITS DEWPOINTS IN THE LOW 60S POOLING AROUND THE BOUNDARY ARE TOO
HIGH. FOR NOW HAVE CONTINUED SOME CHANCES OF PRECIPITATION FOR THE
FRONT...BUT BELIEVE THE DRIER 11.00Z ECMWF/CANADIAN/NAM WILL COME
TRUE. MUCH COOLER AND DRIER AIR SINKS SOUTH INTO THE AREA SUNDAY
NIGHT IN THE WAKE OF THE FRONT.
MONDAY AND TUESDAY STILL LOOK LIKE A TASTE OF FALL AS A SHOT OF
MODIFIED ARCTIC AIR COMES INTO THE REGION. AN UPPER LOW WITHIN THE
DEEP UPPER TROUGH IS PROGGED TO SLIDE ACROSS NORTHERN WI MONDAY
EVENING. COOL TEMPERATURES ALOFT...DAYTIME HEATING AND DPVA AHEAD OF
THE UPPER LOW SHOULD PROMOTE SHOWER DEVELOPMENT ACROSS MUCH OF THE
REGION MONDAY. THIS WILL BE ESPECIALLY TRUE OVER NORTHERN WI. HAVE
RAISED PRECIPITATION CHANCES AND FURTHER INCREASES MAY BE NECESSARY.
PRECIPITATION CHANCES CONTINUE INTO TUESDAY AS WELL WITH THE COLD
AIR ALOFT STILL AROUND. 850MB TEMPERATURES PLUMMET TO 4-6C ON MONDAY
ON A BREEZY NORTHWEST WIND AND HOLD THERE THROUGH TUESDAY. THESE ARE
2-2.5 STANDARD DEVIATIONS BELOW NORMAL SUGGESTING RECORDS ARE
POSSIBLE. SEE CLIMATE SECTION BELOW FOR MORE DETAILS.
THE WEATHER QUIETS DOWN THEN FOR WEDNESDAY AND THROUGH THE END OF
THE WEEK AS THE DEEP UPPER TROUGH GRADUALLY EJECTS OUT. PLENTIFUL
DRY CANADIAN AIR PLUNGES SOUTH THROUGH MUCH OF THE EASTERN U.S....
RESULTING IN A DRY FORECAST FOR WEDNESDAY AND BEYOND. TEMPERATURES
WILL GRADUALLY WARM EACH DAY AS THE SUN HELPS MODIFY THE COLD AIR.
WE SHOULD BE BACK CLOSE TO NORMAL BY NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1250 PM CDT FRI JUL 11 2014
A BAND OF LIGHT RAIN AND A FEW THUNDERSTORMS WILL MOVE THROUGH THE
TAF REGION EARLY THIS AFTERNOON. THESE SHOWERS LOOK LIKE THEY ARE
MAINLY EAST OF RST ALREADY...SO IT WILL MAINLY BE LSE THAT IS
UNDER THE THREAT OF SEEING SOME BRIEFLY LOWER CONDITIONS TO
MVFR/IFR. AFTER A PERIOD OF VFR THIS AFTERNOON...2-3KFT CLOUD
COVER SHOULD MOVE IN THIS EVENING AHEAD OF THE COLD FRONT AND
REMAIN STUCK OVER THE REGION INTO TOMORROW MORNING. WHILE SOME
SPOTTY RAIN SHOWERS/STORMS ARE POSSIBLE LATE THIS AFTERNOON INTO
TONIGHT...THE NEXT MAIN THREAT IS NOT EXPECTED TO ARRIVE UNTIL
TOMORROW AFTERNOON.
&&
.CLIMATE...
ISSUED AT 255 AM CDT FRI JUL 11 2014
RECORD COOL HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY AS AN
UNSEASONABLY COLD AIRMASS SETTLES OVER THE UPPER MISSISSIPPI
RIVER VALLEY. FORECAST HIGH TEMPERATURES FOR TUESDAY ARE 65 AT
ROCHESTER AND 66 AT LA CROSSE. THESE TEMPERATURES WOULD BREAK THE
RECORD LOWEST HIGH TEMPERATURES FOR JULY 15TH. THE OLD RECORDS ARE
68 AT LA CROSSE SET BACK IN 1962 AND 67 AT ROCHESTER ALSO SET
BACK IN 1962.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...AJ
LONG TERM....AJ
AVIATION...HALBACH
CLIMATE......AJ