Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/06/15


AREA FORECAST DISCUSSION
NWS TUCSON AZ
900 AM MST TUE AUG 4 2015 .SYNOPSIS...DRIER AND HOTTER CONDITIONS WILL CONTINUE ACROSS SOUTHEAST ARIZONA INTO MID WEEK...WITH LITTLE OR NO THUNDERSTORM ACTIVITY. AS HIGH PRESSURE SHIFTS BACK EAST OF THE AREA...INCREASING MOISTURE WILL BRING AN INCREASING THUNDERSTORM TREND LATER IN THE WEEK INTO THE COMING WEEKEND. AS THIS HAPPENS TEMPERATURES WILL FALL BACK CLOSER TO SEASONAL AVERAGES. && .DISCUSSION...THE 12Z KTWC SOUNDING SHOWS A HAPPY ATMOSPHERE WITH LITTLE INCLINATION TOWARD A NEED TO CORRECT THINGS WITH STRONG CONVECTION. BELOW AVERAGE MOISTURE WITH 1 INCH PRECIPITABLE WATER AND PLENTY OF CONVECTIVE INHIBITION. CURRENT DRY AND HOT FORECAST LOOKS SOLID. AN EXTREMELY UNFAVORABLE RIDGE POSITION AND ORIENTATION OVERHEAD WITH DECLINING MOISTURE TRENDS NOTED ON CIRA LAYERED PRECIPITABLE WATER IMAGERY EVEN ACROSS NORTHERN SONORA AND NORTHWEST CHIHUAHUA. HOWEVER...A MORE FAVORABLE MONSOON PATTERN WILL GRADUALLY RETURN OVER THE NEXT SEVERAL DAYS. PLEASE SEE THE PREVIOUS DISCUSSION BELOW FOR ADDITIONAL DETAILS. && .AVIATION...VALID THRU 05/12Z. MOSTLY CLEAR SKIES THRU 04/18Z...THEN FEW-SCT CLOUDS AT 8-12K FT AGL...MAINLY EAST OF KTUS THRU 05/05Z. MOSTLY CLEAR SKIES AGAIN AFT 05/05Z. SFC WINDS GENERALLY LESS THAN 12 KTS WITH A FEW HIGHER GUSTS DURING THE AFTERNOON/EARLY EVENING HOURS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...DRY CONDITIONS ARE EXPECTED ACROSS MOST OF SOUTHEAST ARIZONA TODAY...ALONG WITH ABOVE NORMAL TEMPERATURES...AND DAYTIME MINIMUM RELATIVE HUMIDITY VALUES FALLING INTO THE 10 TO 20 PCT RANGE. INCREASING PRECIPITATION CHANCES ARE THEN EXPECTED INTO THE UPCOMING WEEKEND AS HIGH PRESSURE SHIFTS FROM NEARLY OVERHEAD... EASTWARD INTO THE SOUTHERN PLAINS. OUTSIDE OF ANY THUNDERSTORM WIND GUSTS...20-FT WINDS WILL GENERALLY BE TERRAIN DRIVEN AND LESS THAN 15 MPH. HOWEVER...THERE WILL BE SOME AFTERNOON AND EARLY EVENING BREEZINESS...ESPECIALLY IN THE GILA VALLEY RIVER VALLEY NEAR SAFFORD. && .CLIMATE...STRONG HIGH PRESSURE WILL BUILD OVER THE AREA TODAY INTO WEDNESDAY...BRINGING HOT EARLY AUGUST TEMPERATURES TO THE AREA...WITH A FEW SPOTS APPROACHING OR TYING RECORD HIGHS. NOT ALL LOCATIONS IN SE AZ WILL GET INTO THE NEAR RECORD HEAT. BELOW ARE THE SITES THAT WILL BE AT OR WITHIN THREE DEGREES TODAY AND WEDNESDAY. DATE AUG 04 AUG 05 FCST RCD/YEAR FCST RCD/YEAR TUCSON INTL AIRPORT 107 109/1994 108 108/2009 FORT THOMAS 105 107/1995 106 109/2009 SAFFORD AG STATION 104 106/2009 105 108/1995 WITH A FORECAST HIGH OF 107 AT TUCSON AIRPORT TODAY...THIS WILL MARK THE 7TH TIME SINCE 1895 THAT AUGUST HIT 105 OR HOTTER WHEN IT DIDN`T OCCUR IN JULY. THE PREVIOUS SIX OCCURRENCES WERE IN 1914/1919/1945/1962/1975 AND 1977. && .PREV DISCUSSION...CLEAR TO MOSTLY CLEAR SKIES PREVAIL ACROSS ALL OF THE CWA EARLY THIS MORNING THANKS IN PART TO THE GRADUAL TOP-DOWN DRYING THAT WE STARTED BACK ON SUNDAY. A LOOK AT THE UPPER-LEVELS SHOWS AN UNUSUAL PATTERN FOR EARLY AUGUST WITH A SW-NE ELONGATED 500 MB RIDGE CENTERED SOMEWHERE JUST WEST OF BAJA CALIFORNIA AND A 300 MB HIGH OVER WEST-CENTRAL CHIHUAHUA MEXICO. THE RESULTING UPPER- LEVEL SWLY FLOW CONTINUES TO REINFORCE HIGH LEVEL DRY AIR...WHICH IS FURTHER BEING AUGMENTED BY WLY/NWLY MID-LEVEL FLOW. THE END RESULT WAS A PWAT VALUE OF 0.93 INCH ON THE 00Z KTWC SOUNDING WITH SIGNS OF CONTINUED SCOURING OF MOISTURE FROM THE COLUMN ALL THE WAY TO THE INTERNATIONAL BORDER PER THE CIRA LAYERED PW PRODUCTS. BASED ON TRENDS ALONE...WE SHOULD SEE EVEN LESS CONVECTIVE ACTIVITY THAN YESTERDAY. AT THIS POINT...AM DISCOUNTING THE RECENT HRRR RUNS WHICH HAVE INSISTED ON DEVELOPING PRECIP IN THE WHITES ALL MORNING LONG AND SUBSEQUENTLY INITIATING CONVECTION THIS AFTERNOON AS FAR NW AS PINAL COUNTY. THAT SAID...DECIDED TO REINTRODUCE LOW-END SLIGHT PRECIP CHANCES IN THE WHITE MOUNTAINS AND THE HIGH TERRAIN OF EXTREME EASTERN COCHISE COUNTY WHERE WE MAY HOLD ONTO JUST ENOUGH MOISTURE TO INITIATE A STORM OR TWO TODAY. THIS IDEA IS SUPPORTED BY THE UNIV. OF AZ WRF RUNS AND THE EXPERIMENTAL HRRR (HRRRX) WHICH HAS...AT LEAST QUALITATIVELY...BEEN OUTPERFORMING THE OPERATIONAL HRRR RECENTLY. WEDNESDAY WILL BE A TRANSITION DAY AS THE MID-LEVEL HIGH BEGINS TO MOVE INTO NM. AS THIS OCCURS...A SMALL INCREASE IN MOISTURE MAY BE ENOUGH TO SET OFF A FEW AFTERNOON/EVENING STORMS NEAR THE INTERNATIONAL BORDER. THIS WILL STILL ONLY BE ISOLATED ACTIVITY. THE BIGGER STORY DURING THE MIDDLE OF THE WEEK WILL BE VERY WARM TEMPERATURES...SOME 8 TO 11 DEGREES ABOVE NORMAL ON TUESDAY AND WEDNESDAY. OUR RECORD HIGH OF 108 (2009) MAY BE IN JEOPARDY ON WEDNESDAY. FOR MORE ON THE POTENTIAL RECORD HEAT PLEASE SEE THE CLIMATE SECTION BELOW. ON THURSDAY AND FRIDAY WE SHOULD SEE A NOTICEABLE UPSWING IN CONVECTIVE COVERAGE AS OUR MID-LEVEL HIGH ROTATES INTO EASTERN NM AND THE SOUTHERN GREAT PLAINS. THE ENSUING SLY/SELY FLOW WILL DRIVE MOISTURE BACK TO ABOVE-CLIMATOLOGICAL LEVELS ACROSS SE AZ. AT THIS TIME...IT APPEARS AS IF WE`LL SEE THE HIGHEST PRECIPITATION COVERAGE ON FRIDAY BUT THIS DOES PARTLY HINGE--AS WE SAW LAST TUESDAY/WEDNESDAY--ON HOW ACTIVE THURSDAY IS. THAT SAID...NUDGED POPS UP A BIT FOR CENTRAL AND EASTERN ZONES. ON SATURDAY AND SUNDAY...NWP SOLUTIONS ARE CONSISTENT IN MOVING A SHORTWAVE TROUGH INTO THE GREAT BASIN WHICH WILL KICK THE HIGH A BIT FARTHER TO THE SOUTH AND EAST. THIS WILL DRIVE THE BEST CHANCES OF PRECIPITATION INTO EASTERN ZONES ON SATURDAY. SOME MOISTURE MAY SLOSH FAR ENOUGH WEST ON SUNDAY TO BRING BETTER CHANCES BACK TO CENTRAL AREAS. THE 04/00Z GFS/ECMWF STILL SHOW AN INVERTED TROUGH POTENTIALLY IMPACTING THE REGION EARLY NEXT WEEK AS MENTIONED BY THE PREVIOUS FORECAST SHIFT. TIMING THESE SUBTLE FEATURES AND THEIR IMPACTS ON OUR WEATHER IS NOTORIOUSLY DIFFICULT--EVEN AT SHORT RANGES. AS SUCH...FOR NOW MAINTAIN NEAR CLIMATOLOGICAL POPS THROUGH THE END OF THE FORECAST PERIOD. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ MEYER PREV DISCUSSION...CARLAW AVIATION/FIRE WEATHER...ZELL CLIMATE...GLUECK VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TUCSON AZ
253 AM MST TUE AUG 4 2015 .SYNOPSIS...DRIER AIR WILL CONTINUE TO BRING LITTLE IF ANY THUNDERSTORM ACTIVITY TO THE REGION ALONG WITH ABOVE NORMAL TEMPERATURES THROUGH THE MIDDLE OF THE WEEK. INCREASING MOISTURE WILL THEN BRING SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS THURSDAY INTO THE UPCOMING WEEKEND ALONG WITH A SLIGHT COOLING TREND. && .DISCUSSION...CLEAR TO MOSTLY CLEAR SKIES PREVAIL ACROSS ALL OF THE CWA EARLY THIS MORNING THANKS IN PART TO THE GRADUAL TOP-DOWN DRYING THAT WE STARTED BACK ON SUNDAY. A LOOK AT THE UPPER-LEVELS SHOWS AN UNUSUAL PATTERN FOR EARLY AUGUST WITH A SW-NE ELONGATED 500 MB RIDGE CENTERED SOMEWHERE JUST WEST OF BAJA CALIFORNIA AND A 300 MB HIGH OVER WEST-CENTRAL CHIHUAHUA MEXICO. THE RESULTING UPPER-LEVEL SWLY FLOW CONTINUES TO REINFORCE HIGH LEVEL DRY AIR...WHICH IS FURTHER BEING AUGMENTED BY WLY/NWLY MID-LEVEL FLOW. THE END RESULT WAS A PWAT VALUE OF 0.93 INCH ON THE 00Z KTWC SOUNDING WITH SIGNS OF CONTINUED SCOURING OF MOISTURE FROM THE COLUMN ALL THE WAY TO THE INTERNATIONAL BORDER PER THE CIRA LAYERED PW PRODUCTS. BASED ON TRENDS ALONE...WE SHOULD SEE EVEN LESS CONVECTIVE ACTIVITY THAN YESTERDAY. AT THIS POINT...AM DISCOUNTING THE RECENT HRRR RUNS WHICH HAVE INSISTED ON DEVELOPING PRECIP IN THE WHITES ALL MORNING LONG AND SUBSEQUENTLY INITIATING CONVECTION THIS AFTERNOON AS FAR NW AS PINAL COUNTY. THAT SAID...DECIDED TO REINTRODUCE LOW-END SLIGHT PRECIP CHANCES IN THE WHITE MOUNTAINS AND THE HIGH TERRAIN OF EXTREME EASTERN COCHISE COUNTY WHERE WE MAY HOLD ONTO JUST ENOUGH MOISTURE TO INITIATE A STORM OR TWO TODAY. THIS IDEA IS SUPPORTED BY THE UNIV. OF AZ WRF RUNS AND THE EXPERIMENTAL HRRR (HRRRX) WHICH HAS...AT LEAST QUALITATIVELY...BEEN OUTPERFORMING THE OPERATIONAL HRRR RECENTLY. WEDNESDAY WILL BE A TRANSITION DAY AS THE MID-LEVEL HIGH BEGINS TO MOVE INTO NM. AS THIS OCCURS...A SMALL INCREASE IN MOISTURE MAY BE ENOUGH TO SET OFF A FEW AFTERNOON/EVENING STORMS NEAR THE INTERNATIONAL BORDER. THIS WILL STILL ONLY BE ISOLATED ACTIVITY. THE BIGGER STORY DURING THE MIDDLE OF THE WEEK WILL BE VERY WARM TEMPERATURES...SOME 8 TO 11 DEGREES ABOVE NORMAL ON TUESDAY AND WEDNESDAY. OUR RECORD HIGH OF 108 (2009) MAY BE IN JEOPARDY ON WEDNESDAY. FOR MORE ON THE POTENTIAL RECORD HEAT PLEASE SEE THE CLIMATE SECTION BELOW. ON THURSDAY AND FRIDAY WE SHOULD SEE A NOTICEABLE UPSWING IN CONVECTIVE COVERAGE AS OUR MID-LEVEL HIGH ROTATES INTO EASTERN NM AND THE SOUTHERN GREAT PLAINS. THE ENSUING SLY/SELY FLOW WILL DRIVE MOISTURE BACK TO ABOVE-CLIMATOLOGICAL LEVELS ACROSS SE AZ. AT THIS TIME...IT APPEARS AS IF WE`LL SEE THE HIGHEST PRECIPITATION COVERAGE ON FRIDAY BUT THIS DOES PARTLY HINGE--AS WE SAW LAST TUESDAY/WEDNESDAY--ON HOW ACTIVE THURSDAY IS. THAT SAID...NUDGED POPS UP A BIT FOR CENTRAL AND EASTERN ZONES. ON SATURDAY AND SUNDAY...NWP SOLUTIONS ARE CONSISTENT IN MOVING A SHORTWAVE TROUGH INTO THE GREAT BASIN WHICH WILL KICK THE HIGH A BIT FARTHER TO THE SOUTH AND EAST. THIS WILL DRIVE THE BEST CHANCES OF PRECIPITATION INTO EASTERN ZONES ON SATURDAY. SOME MOISTURE MAY SLOSH FAR ENOUGH WEST ON SUNDAY TO BRING BETTER CHANCES BACK TO CENTRAL AREAS. THE 04/00Z GFS/ECMWF STILL SHOW AN INVERTED TROUGH POTENTIALLY IMPACTING THE REGION EARLY NEXT WEEK AS MENTIONED BY THE PREVIOUS FORECAST SHIFT. TIMING THESE SUBTLE FEATURES AND THEIR IMPACTS ON OUR WEATHER IS NOTORIOUSLY DIFFICULT--EVEN AT SHORT RANGES. AS SUCH...FOR NOW MAINTAIN NEAR CLIMATOLOGICAL POPS THROUGH THE END OF THE FORECAST PERIOD. && .AVIATION...VALID THRU 05/12Z. MOSTLY CLEAR SKIES THRU 04/16Z...THEN FEW-SCT CLOUDS AT 8-12K FT AGL...MAINLY EAST OF KTUS THRU 05/05Z. MOSTLY CLEAR SKIES AGAIN AFT 05/05Z. SFC WINDS GENERALLY LESS THAN 12 KTS WITH A FEW HIGHER GUSTS DURING THE AFTERNOON/EARLY EVENING HOURS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...DRY CONDITIONS ARE EXPECTED ACROSS MOST OF SOUTHEAST ARIZONA TODAY...ALONG WITH ABOVE NORMAL TEMPERATURES...AND DAYTIME MINIMUM RELATIVE HUMIDITY VALUES FALLING INTO THE 10 TO 20 PCT RANGE. INCREASING PRECIPITATION CHANCES ARE THEN EXPECTED INTO THE UPCOMING WEEKEND AS HIGH PRESSURE SHIFTS FROM NEARLY OVERHEAD... EASTWARD INTO THE SOUTHERN PLAINS. OUTSIDE OF ANY THUNDERSTORM WIND GUSTS...20-FT WINDS WILL GENERALLY BE TERRAIN DRIVEN AND LESS THAN 15 MPH. HOWEVER...THERE WILL BE SOME AFTERNOON AND EARLY EVENING BREEZINESS...ESPECIALLY IN THE GILA VALLEY RIVER VALLEY NEAR SAFFORD. && .CLIMATE...STRONG HIGH PRESSURE WILL BUILD OVER THE AREA TODAY INTO WEDNESDAY...BRINGING HOT EARLY AUGUST TEMPERATURES TO THE AREA...WITH A FEW SPOTS APPROACHING OR TYING RECORD HIGHS. NOT ALL LOCATIONS IN SE AZ WILL GET INTO THE NEAR RECORD HEAT. BELOW ARE THE SITES THAT WILL BE AT OR WITHIN THREE DEGREES TODAY AND WEDNESDAY. DATE AUG 04 AUG 05 FCST RCD/YEAR FCST RCD/YEAR TUCSON INTL AIRPORT 107 109/1994 108 108/2009 FORT THOMAS 105 107/1995 106 109/2009 SAFFORD AG STATION 104 106/2009 105 108/1995 WITH A FORECAST HIGH OF 107 AT TUCSON AIRPORT TODAY...THIS WILL MARK THE 7TH TIME SINCE 1895 THAT AUGUST HIT 105 OR HOTTER WHEN IT DIDN`T OCCUR IN JULY. THE PREVIOUS SIX OCCURRENCES WERE IN 1914/1919/1945/1962/1975 AND 1977. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...CARLAW AVIATION/FIRE WEATHER...ZELL CLIMATE...GLUECK VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS RENO NV
240 PM PDT TUE AUG 4 2015 .SYNOPSIS... LOW PRESSURE MOVING INTO NORTHERN CALIFORNIA WILL BRING LOW CHANCES FOR THUNDERSTORMS THIS EVENING WELL NORTH OF INTERSTATE 80. DRIER WEST FLOW RETURNS FOR MID WEEK, THEN AN INCREASED CHANCE FOR SHOWERS AND THUNDERSTORMS RETURNS THURSDAY NIGHT AND FRIDAY AS LOW PRESSURE APPROACHES THE SIERRA AND WESTERN NEVADA. FOR THIS WEEKEND, DRY WEATHER RETURNS WITH TEMPERATURES SLIGHTLY BELOW NORMAL. && .SHORT TERM... THE BLM REPORTED THAT THE DODGE FIRE IN A REMOTE AREA OF NORTHEAST LASSEN COUNTY HAD BURNED 3,500 ACRES AS OF NOON TODAY. ZEPHYR WIND GUSTS THIS EVENING AND AGAIN WEDNESDAY WITH PEAK GUSTS UP TO 30 MPH SHOULD INCREASE SMOKE OUTPUT FROM THE DODGE FIRE DURING THE LATE AFTERNOON AND EVENING PERIODS. SMOKE AND HAZE FROM THIS FIRE MAY REACH THE SURPRISE VALLEY AND NORTHERN WASHOE COUNTY THROUGH THIS EVENING AS WEST WINDS PREVAIL. AS WINDS SHIFT TO THE NORTHWEST OVERNIGHT, SMOKE MAY SPREAD ACROSS GERLACH AND POSSIBLY AS FAR SOUTH AS LOVELOCK AND PYRAMID LAKE. CURRENT SATELLITE IMAGERY SHOWS A WEATHER IMPULSE WHICH WILL TRACK ACROSS NORTHEAST CA AND NORTHERN NV THIS EVENING AND OVERNIGHT. HRRR MODEL FORECAST INDICATES SHOWERS AS FAR SOUTH AS MONO/MINERAL COUNTIES WITH THIS FEATURE. HOWEVER, TRENDS AND OPERATIONAL MODELS SHOW MORE ENERGY AND INSTABILITY NEAR THE OREGON BORDER. THE GFS SOLUTION IS PREFERRED WITH ISOLATED THUNDERSTORMS ROUGHLY NORTH OF A SUSANVILLE-LOVELOCK LINE AND VIRGA/SPRINKLES ALONG THE SIERRA FROM THE TAHOE BASIN SOUTH TO MONO COUNTY. THE EASTERN SIERRA AND WESTERN NV ARE BETWEEN SYSTEMS WEDNESDAY THROUGH THURSDAY WITH TYPICAL AFTERNOON ZEPHYR WIND GUSTS UP TO 30 MPH EXPECTED. A SIGNIFICANT WEATHER SYSTEM IS EXPECTED TO ARRIVE THURSDAY NIGHT. THERE IS POTENTIAL FOR ELEVATED, QUICK MOVING NOCTURNAL THUNDERSTORMS THURSDAY NIGHT ACROSS THE SIERRA. THE MAIN CONCERN WITH THESE STORMS THURSDAY NIGHT IS THE THREAT FOR NEW FIRE STARTS. CURRENT GUIDANCE SHOWS THE UPPER JET CROSSING THE SIERRA OVER THE TAHOE BASIN THURSDAY EVENING, WHICH WOULD PROVIDE THE BEST CHANCES FOR THESE NOCTURNAL STORMS FROM THE TAHOE BASIN NORTH ACROSS PLUMAS AND LASSEN COUNTIES. FORECAST CONFIDENCE IS MEDIUM AND ABOVE AVERAGE REGARDING THE TRACK OF THIS LOW AND ITS ASSOCIATED MOISTURE PLUME. HOWEVER, SUBTLE CHANGES TO THE FORECAST TIMING AND TRACK MAY CHANGE THE LOCATION, INTENSITY AND COVERAGE OF THE STORM THREAT THURSDAY NIGHT (SO PLEASE STAY TUNED TO THE FORECAST). JCM .LONG TERM...FRIDAY THROUGH MONDAY... FOR FRIDAY, WE HAVE CONTINUED TO TREND UPWARD WITH THUNDERSTORM CHANCES, AS MEDIUM RANGE GUIDANCE CONTINUES TO MOVE A POTENT UPPER LOW ACROSS THE SIERRA AND WESTERN NV. THE MINOR TIMING DIFFERENCES BETWEEN GUIDANCE DATA MAY AFFECT THE AMOUNT AND LOCATION OF CONVECTION FRIDAY MORNING, BUT OVERALL IT APPEARS THAT MUCH OF THE REGION CAN EXPECT AT LEAST SCATTERED THUNDERSTORM COVERAGE FRIDAY AFTERNOON AND EVENING. THERE ARE SOME FIRE WEATHER CONCERNS WITH POSSIBLE NEW FIRE STARTS DUE TO FAST CELL MOTION AND LIGHTNING STRIKES OUTSIDE MAIN PRECIP CORES. HOWEVER, LOW LEVEL MOISTURE IS MORE LIKELY TO INCREASE RATHER QUICKLY AS STRONGER STORMS DEVELOP. THE AMOUNT OF INSTABILITY AND FORCING ASSOCIATED WITH THIS LOW WILL BRING AN ELEVATED THREAT FOR SEVERE STORMS PRODUCING HAIL, STRONG OUTFLOW WINDS AND LOCALLY HEAVY RAINFALL. WITH WIDESPREAD OUTDOOR EVENTS TAKING PLACE ACROSS MUCH OF THE REGION FRIDAY, PARTICIPANTS ARE STRONGLY ENCOURAGED TO PLAN AHEAD AND ENSURE A QUICK ACCESS TO SAFE SHELTER BEFORE DANGEROUS STORMS ARRIVE. FOR FRIDAY NIGHT, THIS LOW IS PROJECTED TO EXIT TO THE NORTHEAST WITH CONVECTION WINDING DOWN. FOR SATURDAY, THERE MAY BE A FEW AFTERNOON CELLS IN FAR NORTHEAST CA AND NORTHWEST NV NEAR THE OREGON BORDER, BUT OVERALL A DRIER AND MORE STABLE AIR MASS WILL SPREAD ACROSS THE REGION AS FLOW ALOFT BECOMES WEST. MAX TEMPS ON SATURDAY ARE EXPECTED TO BE A FEW DEGREES BELOW NORMAL, GENERALLY IN THE MID- UPPER 80S FOR MOST LOWER ELEVATIONS. FOR SUNDAY THROUGH NEXT TUESDAY, TROUGH DEVELOPING IN THE PACIFIC NORTHWEST IS EXPECTED TO KEEP DRY SOUTHWEST FLOW ALOFT OVER THE SIERRA AND WESTERN NV. SCATTERED CIRRUS AND SOME FLAT AFTERNOON CUMULUS ARE POSSIBLE EACH DAY, BUT THUNDERSTORMS ARE UNLIKELY. TEMPS WILL REBOUND SLIGHTLY TO NEAR SEASONAL NORMALS AROUND 90 DEGREES IN LOWER ELEVATIONS BY SUNDAY, AND SHOULD HOLD NEARLY STEADY THROUGH TUESDAY. AFTERNOON ZEPHYR-TYPE BREEZES WITH GUSTS 25-30 MPH ARE FORECAST EACH DAY, WHICH COULD LEAD TO EMERGENCE AND SPREAD OF ANY HOLDOVER LIGHTNING FIRES RESULTING FROM FRIDAY`S THUNDERSTORM EVENT. MJD && .AVIATION... VFR CONDITIONS EXPECTED AT THE MAIN TERMINALS THRU WEDNESDAY, ALTHOUGH WIDESPREAD MID-HIGH LEVEL CLOUD COVER WILL PREVAIL WITH POSSIBLE BRIEF LIGHT SHOWERS THROUGH THIS EVENING. THE PROBABILITY FOR MEASURABLE RAINFALL AT ANY OF THE MAIN TERMINALS IS LESS THAN 20 PERCENT. ISOLATED THUNDERSTORMS ARE POSSIBLE NORTH OF SUSANVILLE AND GERLACH THROUGH TONIGHT. ALSO, AREAS OF SMOKE AND HAZE FROM THE DODGE FIRE MAY SPREAD ACROSS NORTHWEST NV AND PRODUCE SOME REDUCED VISIBILITY FROM GERLACH NORTHWARD TO THE OREGON BORDER. ADDITIONAL SMOKE COULD SPREAD SOUTH TO NEAR PYRAMID LAKE BY WEDNESDAY AFTERNOON. CLOUD COVER LIKELY TO LIMIT WIND SPEEDS THIS AFTERNOON, BUT SOME GUSTS 20-25 KT ARE POSSIBLE THIS EVENING AS SHORTWAVE PASSES THROUGH. FOR WEDNESDAY, TYPICAL W-NW ZEPHYR TYPE BREEZES EXPECTED AT AREA TERMINALS WITH PEAK GUSTS UP TO 25 KT MAINLY BETWEEN 21Z-04Z. MJD && .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 SACRAMENTO CA
1015 AM PDT TUE AUG 4 2015 .SYNOPSIS... COOLER WEATHER EARLY THIS WEEK WITH TEMPERATURES BELOW AVERAGE FOR EARLY AUGUST THROUGH WEDNESDAY. SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS TODAY WITH A BETTER CHANCE THURSDAY NIGHT INTO FRIDAY. && .DISCUSSION... A SHORT-WAVE WILL MOVE ACROSS NORCAL TODAY. LATEST HRRR & NAM MODELS SHOW FORECAST RADAR REFLECTIVITY ACROSS OUR CWA THIS AFTERNOON. HOWEVER, THE REFLECTIVITY DOESN`T LOOK LIKE IT WILL PRODUCE MUCH RAIN (GENERALLY LESS THAN 30 DBZ)...PERHAPS SOME SPRINKLES IN THE VALLEY WITH SOME ISOLATED MOUNTAIN THUNDERSTORMS...MAINLY ALONG THE COASTAL RANGE. HAVE MADE A SLIGHT MODIFICATION TO THIS MORNING`S FORECAST PACKAGE TO REMOVE MENTION OF THUNDERSTORMS IN THE VALLEY AND CHANGE IT TO SPRINKLES, BUT WILL KEEP SLIGHT CHANCE OF THUNDERSTORMS IN THE MOUNTAIN AREAS. OTHERWISE, EXPECT DAYTIME HIGHS TO BE ABOUT 5-10 DEGREES BELOW NORMAL WITH MUCH OF THE VALLEY IN THE 80S. THE WAVE SHIFTS EAST ALLOWING SHORT-WAVE RIDGING TO BRING WARMER AND DRIER WEATHER WEDNESDAY AND THURSDAY. ANOTHER LOW APPROACHES THURSDAY EVENING THROUGH FRIDAY AND WILL BRING A RETURN OF SHOWER AND THUNDERSTORM CHANCES ALONG WITH COOLER TEMPS. THIS LOW IS BETTER ORGANIZED THAN TODAY`S SHORT-WAVE SO THUNDERSTORM CHANCES WILL BE MORE WIDESPREAD ACROSS THE MOUNTAINS AND COULD ALSO IMPACT THE VALLEY. JBB && .EXTENDED DISCUSSION (SATURDAY THROUGH TUESDAY) THE UPPER TROUGH EXITS ON SATURDAY WITH SOME LINGERING SHOWER AND THUNDERSTORM ACTIVITY IN THE MOUNTAINS. BY LATE AFTERNOON, MUCH OF THIS SHOULD BE SHIFTING OUT OF THE AREA WITH FLAT RIDGING DEVELOPING AND MAINLY DRY WEATHER. TEMPERATURES ON SATURDAY SHOULD BE BELOW NORMAL. RIDGING DEVELOPS TO THE EAST ON SUNDAY, WITH DRIER, MORE STABLE SOUTHWEST FLOW OVER THE AREA. THERE IS A SMALL POSSIBILITY OF SOME PRECIPITATION OVER FAR NORTHERN SHASTA COUNTY SUNDAY AFTERNOON AND EVENING AS A LOW FROM THE GULF OF ALASKA SLOWLY DROPS DOWN THE COAST, BUT THE BULK OF IT SHOULD STAY WELL TO THE NORTH. WHERE THIS LOW ENDS UP WILL DETERMINE THE POTENTIAL FOR RAIN NEXT WEEK. THE ECMWF SPLITS OF PART OF THE TROUGH AND SENDS IT SOUTHWARD AS A LOW SITTING OFF THE CENTRAL CALIFORNIA COAST...WHILE THE GFS GRADUALLY BRINGS AN UPPER LOW INTO THE PACIFIC NORTHWEST. WILL GO WITH A DRY FORECAST FOR NOW, WITH EITHER POSSIBILITY LIKELY DELAYING PRECIPITATION INTO MID WEEK. EK && .AVIATION... DRY WEATHER WITH VFR THIS MORNING. SW WINDS IN THE DELTA HAVE DECREASED, BUT WILL STREGTHEN AGAIN THIS EVENING AND OVERNIGHT WITH PEAK GUSTS UP TO 25-30 KTS. SOME SMOKE NEAR WILDFIRES MAY LIMIT VISIBILITY. AFTERNOON AND EVENING THUNDERSTORMS ARE POSSIBLE OVER THE MOUNTAINS. GUSTY, ERRATIC WINDS ARE THE MAIN CONCERN WITH ANY STORMS THAT FORM. EK/JBB && .STO WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1119 PM MDT MON AUG 3 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 238 PM MDT MON AUG 3 2015 AN UPR TROF WL CONTINUE WORKING ITS WAY NORTHEASTWARD OVR CO THRU THIS EVENING...AND WL CONTINUE PRODUCING SHOWERS AND TSTMS DURING THIS TIME OVR NRN AND ERN CO. SATELLITE IMAGES SHOW DRIER AIR WORKING ITS WAY EASTWARD BEHIND THIS UPR TROF. OVR THE FORECAST AREA...MUCH OF THE MORE WIDESPREAD AND HEAVIER PCPN ASSOCIATED WITH THE UPR TROF WL LIKELY BE WORKING ITS WAY NORTH AND EAST OF THE AREA BY LATE AFTERNOON OR EARLY EVENING...BUT THE HRRR IS SHOWING ANOTHER ROUND OF CONVECTION MOVING EASTWARD OFF THE ERN MTNS AFTER ABOUT 01Z. WITH SUFFICIENT CAPE AND MARGINAL SHEAR...THERE IS THE POSSIBILITY OF ONE OR TWO STORMS BECOMING SVR OR MARGINALLY SVR THRU EARLY THIS EVENING OVR THE ERN PLAINS. BY MIDNIGHT MUCH OF THE CONVECTION SHOULD HAVE ENDED...ALTHOUGH SOME LINGERING ACTIVITY COULD CONTINUE OVR THE FAR SERN PLAINS A BIT LONGER. AN UPR RIDGE WL THEN BE BUILDING OVR THE AREA THRU TUE. ALTHOUGH THERE WL BE DRIER AIR OVR THE AREA ON TUE...THERE WL STILL BE ENOUGH MSTR AROUND FOR SOME ISOLD MAINLY AFTERNOON SHOWERS AND TSTMS...MAINLY OVR AND NR THE HYR TRRN. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 238 PM MDT MON AUG 3 2015 ...MONSOON RETURNS FOR THE WEEKEND... HIGH PRESSURE WILL BUILD STRONGLY FROM THE SOUTH FOR THE MID-WEEK PERIOD...AS THE H5 CENTER SHIFTS OVER CENTRAL NM. A WEAK SHORTWAVE WILL CROSS THROUGH WY WED NIGHT...BUT MOST OF THE IMPACT WILL BE NORTH OF OUR CWA. THIS DISTURBANCE COULD SPARK SOME ISOLD TO CT STORMS OVER THE MTS LATE WED...BUT OTHERWISE IT WILL BE DRY...AND THE WEAK ZONAL FLOW WILL BRING THE UPPER 90S BACK TO MOST OF SE CO...ALONG WITH 80S FOR THE HIGHER ELEVATIONS. THURSDAY LOOKS EVEN MORE HOT AND DRY...WITH TEMPS POSSIBLY AROUND 100 DEGREES FOR THE HOT SPOTS ALONG THE LOWER ARKANSAS VALLEY. ANOTHER WEAK DISTURBANCE WILL MOVE THROUGH THE RIDGE LATE IN THE DAY...BUT TS COVERAGE SHOULD BE ISOLD AT BEST. FRIDAY WILL CONTINUE TO BE WARM AS THE UPPER HIGH SHIFTS BACK EWD INTO TX...AND SW FLOW ESTABLISHES ITSELF OVER CO. THE MONSOONAL PLUME WILL BEGIN WORKING ITS WAY BACK INTO WRN CO AS A TROUGH MOVES ASHORE OVER NRN CA...AND THEN TRANSLATES NEWD INTO THE INTER-MOUNTAIN REGION ON SATURDAY. EXPECT WIDESPREAD STORMS OVER THE MTS THROUGH SAT NIGHT AS THE DEPARTING TROUGH STRENGTHENS MONSOONAL FLOW INTO SW CO. THE ERN ZONES MAY NOT SEE AS MUCH WIDESPREAD PRECIP COVERAGE...BUT STILL SHOULD SEE AT LEAST ISOLD-SCT AFTERNOON AND EVENING STORMS. BEYOND SATURDAY...THE FORECAST BECOMES A BIT MORE UNCERTAIN. MODEL CONSENSUS SUGGESTS THAT THE UPPER HIGH WILL GRADUALLY SHIFT BACK TO THE WEST...BRINGING OUR AREA BACK TO A DRY AND HOT SUMMER PATTERN. BUT HOW FAST THIS WILL OCCUR IS DEBATABLE. THE GFS RETURNS US TO THIS DRY AND HOT PATTERN AS SOON AS SUNDAY...WHILE THE ECMWF HOLDS OFF TIL LATER NEXT WEEK. THE ENSEMBLES MAKE IT CLEAR THAT THERE WILL BE A TROUGH SOMEWHERE OVER THE PACNW...AND A RIDGE SOMEWHERE OVER THE SOUTHERN PLAINS...BUT SUBTLE SHIFTS IN THE OVERALL PATTERN WILL DETERMINE DAILY POPS AND TEMPS. SO...PERSISTENCE SEEMS TO BE THE BEST BET AT THIS POINT...WITH NO SIGNIFICANT PRECIP AND TEMPS AT OR SLIGHTLY ABOVE AVERAGE FOR THIS PERIOD. ROSE && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1117 PM MDT MON AUG 3 2015 VFR CONDITIONS ARE ANTICIPATED DURING THE NEXT 24H AT ALL 3 TAF SITES...KPUB...KALS AND KCOS. WINDS WILL BE LIGHT AND DIURNALLY DRIVEN. DRIER AIR IS MOVING INTO THE REGION TONIGHT. ALTHOUGH I CANNOT RULE OUT AN ISOLD TSRA TOMOROW AFTERNOON AT ANY OF THE 3 TAF SITES...THE PROBABILITY OF IT OCCURRING IS QUITE LOW AT THIS TIME. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...ROSE AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS ALBANY NY
725 PM EDT WED AUG 5 2015 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE OVER QUEBEC WILL CONTINUE TO ALLOW FOR A STRAY SHOWER THIS EVENING...ESPECIALLY FOR NORTHERN AREAS. OTHERWISE...SKIES WILL BE PARTLY TO MOSTLY CLEAR WITH COOL TEMPERATURES TONIGHT. DRY AND QUIET WEATHER IS EXPECTED INTO THE UPCOMING WEEKEND WITH TEMPERATURES SLIGHTLY BELOW NORMAL...ALONG WITH COMFORTABLE LEVELS OF HUMIDITY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 725 PM EDT...A LARGE CLOSED OFF LOW AT 500 HPA IS SITUATED DIRECTLY NORTH OF THE REGION OVER NORTH CENTRAL QUEBEC. THE TROUGH AXIS CONTINUES TO MOVE EASTWARD ACROSS OUR REGION EARLY THIS EVENING...WITH SOME BRIEF ISOLATED RAIN SHOWERS ACROSS NORTHERN AREA. A FEW ADDITIONAL RAIN SHOWERS ARE POSSIBLE THROUGH THE EARLY EVENING HOURS...WITH THE BEST CHANCE ACROSS THE HIGH TERRAIN OF SOUTHERN VERMONT AND SOUTHERN/WESTERN ADIRONDACKS. WILL REMOVE ANY MENTION OF THUNDER FOR THE REST OF THE EVENING DUE TO STABILIZATION OCCURRING. THE 3KM HRRR CONTINUES TO SHOW SHOWER ACTIVITY OVER THE TUG HILL AND ST LAWRENCE VALLEY WILL WORK TOWARDS THE WESTERN ADIRONDACKS...BUT WILL START TO DIMINISH LATER THIS EVENING WITH THE LOSS OF DAYTIME HEATING...AND THE BEST FORCING SHIFTING NORTH AND EAST OF THE REGION. AS A RESULT...WILL ALLOW POPS TO DROP OFF BY MIDNIGHT FOR THE WHOLE AREA. CLOUDS WILL DIMINISH OVER MOST OF THE AREA FOR THE OVERNIGHT HOURS WITH SKIES BECOMING MOSTLY CLEAR FOR A GOOD MAJORITY OF THE REGION. TEMPS LOOK COMFORTABLE AND COOL...WITH LOWS MAINLY IN THE 50S. SOME UPPER 40S WILL BE POSSIBLE FOR THE HIGHEST ELEVATIONS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... DRY AND QUIET WEATHER IS ANTICIPATED FOR MUCH OF THE SHORT TERM PERIOD. THE UPPER LEVEL LOW OVER QUEBEC WILL SHIFT TOWARDS ATLANTIC CANADA ON THURSDAY. HEIGHTS WILL GRADUALLY START TO RISE AT 500 HPA...ALTHOUGH A CONTINUED WEST TO NORTHWEST FLOW WILL KEEP TEMPS SOMEWHAT ON THE COOLER SIDE. A WEAK WAVE OVER THE TENNESSEE VALLEY WILL SHIFT TOWARDS THE MID ATLANTIC COAST FOR THURSDAY NIGHT INTO FRIDAY. MODEL GUIDANCE IS PRETTY CONSISTENT ON KEEPING THIS FEATURE SOUTH OF OUR AREA FOR FRIDAY INTO FRIDAY NIGHT...SO WILL KEEP THE FORECAST DRY THROUGH THIS TIME. SKY COVER GENERALLY LOOK PARTLY TO MOSTLY CLEAR. HIGH TEMPS ON THURSDAY AND FRIDAY WILL MAINLY BE IN THE 70S...WITH A FEW SPOTS NEAR 80 IN THE MID HUDSON VALLEY. OVERNIGHT LOWS LOOK TO BE IN THE 50S...WITH SOME COOLER 40S FOR THE HIGH TERRAIN...ESP OVER THE CENTRAL ADIRONDACKS. DEWPOINTS WILL BE VERY COMFORTABLE EACH DAY...MAINLY IN THE 50S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE LONG TERM PERIOD WILL START OUT RELATIVELY QUIET AS A COASTAL STORM PASSES TO THE EAST OF THE REGION...BUT THEN BECOME INCREASINGLY UNSETTLED HEADING INTO EARLY NEXT WEEK AS A FRONTAL BOUNDARY IMPACTS THE REGION. AT THE START OF THE LONG TERM PERIOD...THE FIRST HALF OF THE WEEKEND LOOKS TO START ON AN EXCELLENT NOTE...WITH DRY WEATHER AND MOSTLY SUNNY/PARTLY CLOUDY SKIES SATURDAY. MEANWHILE...A COASTAL STORM WILL BE TAKING SHAPE OFF THE CAROLINA COAST...AND BEGIN TO TRACK NORTHEAST UP THE EASTERN SEABOARD LATE SATURDAY INTO SATURDAY NIGHT. BASED ON THE LATEST LONG RANGE GUIDANCE...THE OVERALL CONSENSUS IS FOR THIS COASTAL STORM...WHICH LOOKS TO BECOME QUITE IMPRESSIVE FOR EARLY AUGUST STANDARDS...IS THAT IT WILL TRACK FAR ENOUGH EAST OFF THE COAST TO HAVE LIMITED IMPACTS ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND. REGARDLESS...THE 12Z ECMWF DOES HINT AT A SLIGHTLY MORE WESTWARD TRACK...WHICH WOULD BRING THE WESTERN EDGE OF RAIN SHOWERS INTO WESTERN NEW ENGLAND AND MAYBE FAR EASTERN NEW YORK. HAVE GONE WITH SLIGHT CHANCE POPS TO TAKE A BLENDED APPROACH SATURDAY NIGHT THROUGH SUNDAY AS THERE STILL REMAINS UNCERTAINTY REGARDING THE EXACT TRACK THAT THE COASTAL STORM WILL TAKE. REGARDLESS OF THE EVENTUAL TRACK...THERE IS FAIRLY HIGH CONFIDENCE THAT THE BULK OF THE PRECIPITATION ASSOCIATED WITH THE COASTAL STORM WILL REMAIN EAST OF THE REGION AS IT TAKES A MILLER TYPE A TRACK/SOUTHERN STREAM DOMINATED SYSTEM/EAST OF CAPE COD. AS THE COASTAL STORM MOVES NORTHEAST INTO THE GULF OF MAINE SUNDAY NIGHT THE REGION WILL BE SANDWICHED BETWEEN THE DEPARTING SYSTEM AND AN APPROACHING FRONTAL BOUNDARY FROM THE GREAT LAKES REGION. IT APPEARS THAT SUNDAY NIGHT...AND PERHAPS MOST OF MONDAY...WILL BE DRY BEFORE THE WEATHER TURNS FOR THE WORSE MONDAY NIGHT. HAVE GONE WITH CHANCE POPS MONDAY NIGHT THROUGH WEDNESDAY WITH THE BEST CHANCE FOR PRECIPITATION TUESDAY INTO TUESDAY NIGHT AS THE FRONTAL BOUNDARY MOVES ACROSS THE REGION. IN ITS WAKE LINGERING SHOWERS WILL BE AROUND WITH A DEEPENING UPPER-LEVEL TROUGH ALOFT. THE 12Z ECMWF STALLS THE FRONT JUST EAST OF THE REGION AND DEVELOPS A WAVE OF LOW PRESSURE THAT WOULD BRING A SOAKING RAINFALL TO THE REGION...WITH THE 12Z GFS HAVING A DRY SCENARIO. IT IS STILL TOO EARLY TO TELL EXACTLY WHAT WILL HAPPEN BUT THERE IS HIGH CONFIDENCE FOR UNSETTLED WEATHER FOR THE START OF NEXT WEEK. HIGH TEMPERATURES THROUGHOUT THE LONG TERM PERIOD WILL GENERALLY RANGE FROM THE LOW 70S TO LOW 80S...WITH A FEW UPPER 60S ACROSS THE HIGH PEAKS OF THE SOUTHERN ADIRONDACKS AND SOUTHERN VERMONT. LOW TEMPERATURES WILL GENERALLY RANGE FROM THE MID 50S TO LOW 60S. && .AVIATION /23Z WEDNESDAY THROUGH MONDAY/... MAINLY VFR CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE 24 HOUR TAF PERIOD ENDING 00Z FRIDAY. THE ONLY EXCEPTION WILL BE FOR A NARROW TIME WINDOW BETWEEN AROUND 08Z-12Z WHEN SOME OCCASIONAL MVFR VSBY WILL BE POSSIBLE AT KGFL/KPSF WITH BR. THICKER FOG FORMATION IS NOT ANTICIPATED DUE TO THE AIR MASS IN THE LOW LEVELS BEING TOO DRY TO SUPPORT FOG. ALSO THERE SHOULD BE JUST ENOUGH MIXING IN THE BOUNDARY LAYER TO PREVENT FOG. FAIR WEATHER IS FORECAST FOR THURSDAY...WITH JUST FEW-SCT MID LEVEL CUMULUS CLOUDS DEVELOPING BY LATE MORNING. WINDS WILL BE WESTERLY AROUND 5 KTS OR LESS TONIGHT AFTER DARK...BECOMING NORTHWEST AROUND 5-10 KTS ON THURSDAY. OUTLOOK... THURSDAY NIGHT TO SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. && .FIRE WEATHER... ASIDE FROM A STRAY SHOWER THIS EVENING...IT LOOKS DRY OVERNIGHT. RH VALUES WILL BE 85 TO 100 PERCENT TONIGHT WITH SOME PATCHY FOG AND DEW FORMATION. WINDS WILL BECOME LIGHT AND VARIABLE. RH VALUES WILL DROP TO 35 TO 55 PERCENT ON BOTH THURSDAY AND FRIDAY AFTERNOONS. THE LOWEST VALUES WILL BE ACROSS THE MID HUDSON VALLEY AND NW CT. WEST TO NORTHWEST WINDS WILL BE AT 5 TO 10 MPH ON THURSDAY...AND NORTH TO NORTHEAST AROUND 5 MPH ON FRIDAY. && .HYDROLOGY... NO HYDROLOGIC PROBLEMS ARE ANTICIPATED OVER THE NEXT FEW DAYS. JUST A STRAY LOCALIZED SHOWER IS POSSIBLE THIS EVENING...MAINLY FOR NORTHERN AREAS. OTHERWISE...DRY WEATHER IS EXPECTED TONIGHT AS AN UPPER LEVEL DISTURBANCE MOVES AWAY FROM THE AREA. DRY WEATHER WILL CONTINUE FOR THURSDAY INTO FRIDAY. JUST A STRAY LIGHT RAIN SHOWER IS POSSIBLE OVER THE WEEKEND...WITH MOST AREAS STAYING COMPLETELY DRY. THIS WILL ALLOW RIVER LEVELS TO REMAIN STEADY OR SLOWLY FALL OVER THE NEXT FIVE DAYS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS/JPV SHORT TERM...FRUGIS LONG TERM...IRL AVIATION...JPV FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
648 PM EDT TUE AUG 4 2015 .SYNOPSIS... THUNDERSTORMS CONTINUING INTO THE EVENING HOURS MAINLY PUSHING E. CONTINUED STRONG TO SEVERE THREATS. DRY...WARM AND LESS HUMID WEATHER ARRIVES THURSDAY. A PERIOD OF UNSETTLED WEATHER IS POSSIBLE FRIDAY INTO THIS WEEKEND...BUT CONFIDENCE REMAINS LOW REGARDING THE TIMING AND COVERAGE OF ANY POTENTIAL WET WEATHER. && .NEAR TERM /THROUGH WEDNESDAY/... INTO THIS EVENING... STRETCHED MID-LEVEL IMPULSES THRU THE BROADER CYCLONIC FLOW KICKING OFF SCATTERED SHOWERS AND THUNDERSTORMS IN A LINGERING DECENT ENVIRONMENT OF STEEP LAPSE RATES AND MARGINAL INSTABILITY. NOT THINKING AS MUCH UMPF AS EARLIER STORMS...ENVIRONMENT HAS BEEN WORKED OVER TO SOME DEGREE AND WEAKER/STRETCHED MID-LEVEL IMPULSES THROUGH A MORE ZONAL FLOW NOT INVOKING MORE VIGOROUS FORCING AS THE WAVE EARLIER TODAY. STILL EFFECTIVE SHEAR IN EXCESS OF 50 KTS WITH MUCAPES/INSTABILITY ON THE ORDER OF 1K J/KG. WHILE A DOWNWARD TREND IS EVIDENT...STILL CAN NOT RULE OUT A STORM HERE OR THERE KICKING OFF BUT REMAINING SUB-SEVERE. THINK THE HRRR HAS THE RIGHT IDEA...FOCUS ALONG THE MA/RI/CT BORDER WHERE MID-LEVEL ENERGY IS BEING STRETCHED AND ALONG THE N-PERIPHERY OF DRIER AIR DISCERNED PER WATER VAPOR IMAGERY. THUS LIKELY POPS FOR THOSE LOCALES...CHANCE TO SLIGHT CHANCE POPS FOR S/CENTRAL CT AND RI AS WELL AS SE MA INCLUDING THE CAPE/ISLANDS...WELCOMING AS THEY TOOK THE BRUNT EARLIER THIS MORNING. TONIGHT... MID-LEVEL IMPULSE AND ACCOMPANYING TROUGH PUSH E SUBSEQUENTLY EASING THE SURFACE FRONTAL BOUNDARY OFFSHORE ALONG WITH DEEPER MOISTURE AND HIGHER THETA-E AIR. WILL SEE SHOWERS / THUNDERSTORMS PUSH OUT TO SEA WITH SOME OF THE STORMS STRONG TO SEVERE LINGERING LONGEST OVER THE CAPE AND ISLANDS WITHIN A LOW-LEVEL CONVERGENT ENVIRONMENT OF HIGHER THETA-E AIR. ANTICIPATED CONCLUSION SHORTLY AFTER MIDNIGHT OF WET- WEATHER. LIGHT W-WINDS PREVAILING AND DRIER AIR WORKING IN. EXPECT IT TO CLEAR OUT W TO E ACCORDINGLY. LOWS DROPPING IN AND AROUND THE LOW-60S WITH SPOTS N/W INTO THE UPPER-50S AS THERE IS AN OPPORTUNITY FOR RADIATIONAL COOLING TO PROCEED. WITH THAT THERE IS THE POTENTIAL FOR PATCHY DENSE FOG...ESPECIALLY THOSE AREAS WHICH OBSERVED RAIN DURING THE DAY. && .SHORT TERM /WEDNESDAY NIGHT/... WEDNESDAY... MID-LEVEL IMPULSE SWEEPS THRU THE BROAD CYCLONIC FLOW FOLLOWED BY THE MID-LEVEL TROUGH. ROBUST FORCING OF AN ENVIRONMENT SLIGHTLY DRIER BUT COOLER ALOFT. ENOUGH MOISTURE PRESENT. WHILE LESSER INSTABILITY...FREEZING LEVEL HEIGHTS WILL BE LOWER. THE MID-LEVEL ASCENT THROUGH THE COLUMN UPON A BOUNDARY LAYER WHICH IS LIKELY TO BECOME WELL-MIXED WITH DAYTIME HEATING AS INITIAL CONDITIONS WILL BE MOSTLY CLEAR IS LIKELY TO LEAD TO SCATTERED SHOWER ACTIVITY... SOME THUNDERSTORMS...STORMS IN WHICH COULD PRODUCE SMALL HAIL. PERHAPS EVEN A GUSTY WIND THREAT WITH INVERTED-V SOUNDINGS BUT HAVE LOW CONFIDENCE AS MOISTURE IS LIMITED. WILL GO WITH CHANCE POPS AS IT IS DIFFICULT TO PIN DOWN EXACTLY WHERE WEATHER WILL MAKE AN IMPACT. CERTAIN THOUGH THERE IS A THREAT ACROSS THE INTERIOR AWAY FROM THE COAST. A TAD COOLER. HIGHS AROUND THE LOW 80S. SEASONABLE. WEDNESDAY NIGHT... BEHIND THE TROUGH IT LOOKS TO REMAIN A BIT BREEZY W. CAN NOT RULE OUT A FEW LOCALES EXPERIENCING LIGHT WINDS OVERNIGHT. SHOULD SEE QUIET WEATHER AND CLEAR CONDITIONS. ALL FACTORS COMBINED...THERE IS SOME POTENTIAL FOR RADIATIONAL COOLING AND HIGHEST CONFIDENCE IS TO THE N/W WITHIN SHELTERED VALLEY REGIMES. LOWS DOWN INTO THE MID- TO UPPER-50S WHILE LOW-60S ALONG THE COAST. DEWPOINTS IN THE LOW-50S. AN END TO THE HEAT AND HUMIDITY AND QUITE REFRESHING. && .LONG TERM /THURSDAY THROUGH TUESDAY/... HIGHLIGHTS... * UNSETTLED WEATHER REMAINS POSSIBLE FRIDAY INTO THE WEEKEND * TEMPERATURES TRENDING BELOW NORMAL THROUGH MOST IF NOT THE ENTIRE PERIOD OVERVIEW AND MODEL PREFERENCES... NOTING FAIRLY GOOD AGREEMENT WITH 12Z OPERATIONAL MODELS RUNS INTO FRIDAY...THEN EACH GOES ON THEIR MERRY OWN WAY WHICH LENDS TO LOW CONFIDENCE BEYOND FRIDAY. ONE BIG QUESTION WILL BE HOW THE H5 CUTOFF LOW ACROSS QUEBEC AND MARITIMES FLATTENS OUT...WHICH ALSO FLATTENS OUT THE FLOW ACROSS MOST OF THE NORTHERN STREAM. DEPENDING UPON WHETHER THIS UPPER LEVEL SYSTEM FLATTENS OUT WILL DETERMINE HOW FAR S THE LARGE HIGH PRES RIDGE BUILDS OUT OF CENTRAL CANADA. ALSO NOTING A STALLED FRONT S OF THE REGION WHICH HAS A SHORT WAVE MOVING ALONG IT...WHICH COULD PUSH SOME MOISTURE INTO PORTIONS OF SOUTHERN NEW ENGLAND. ANOTHER FLY IN THE OINTMENT IS THE POSSIBLE AMPLIFICATION OF LONG WAVE TROUGH ACROSS THE MID ATLC REGION THIS WEEKEND. NEEDLESS TO SAY...LOW CONFIDENCE FORECAST BEYOND FRIDAY DUE TO THE WIDE VARIANCE OF OP MODEL RUN SOLUTIONS. WENT ALONG WITH MOST AVAILABLE GUIDANCE /EXCEPT GFS/ THROUGH FRIDAY...THEN TRANSITIONED OVER TO AN ENSEMBLE MODEL BLEND SIMILAR TO WPC GUIDANCE FROM SATURDAY ONWARD. DETAILS... THURSDAY...HIGH PRESSURE BUILDS OUT OF CENTRAL CANADA INTO UPSTATE NY. WEAK SHORT WAVE MOVES ACROSS NORTHERN NEW ENGLAND AND...WITH LACK OF AVAILABLE MOISTURE IN THE GENERAL W-NW FLOW...EXPECT DRY CONDITIONS. HIGHS LOOK TO RUN AROUND 80 DEGREES...SLIGHTLY BELOW SEASONAL NORMS. THURSDAY NIGHT THROUGH SATURDAY...SHORT WAVE MOVING ALONG STALLED FRONT FROM THE OHIO VALLEY. COULD START TO SEE SOME MOISTURE MOVING NE INTO N CT/RI/SE MA OVERNIGHT THU NIGHT THEN PUSH FURTHER N DURING FRI. STILL A LOT OF QUESTION ON HOW FAR THIS RAIN WILL PUSH INTO THE REGION...IF AT ALL. FOR NOW...KEPT CONTINUITY GOING FROM THE PREVIOUS FORECAST WITH MAINLY CHANCE POPS...THOUGH LOW LIKELY IN PLACE ACROSS S COASTAL AREAS FRI INTO FRI NIGHT. HAVE LOWERED POPS TO CHANCE FOR EARLY SATURDAY THEN SHOULD PUSH E DURING THE AFTERNOON INTO SAT EVENING. SUNDAY THROUGH WEDNESDAY...MUCH OF THIS FORECAST CONTINUES TO DEPEND UPON THE FRI-SAT PATTERN SETS UP. AT THIS POINT...LOOKS LIKE IT SHOULD BE MAINLY DRY BUT COOL ON SUNDAY. MODELS SIGNALING ANOTHER H5 LONG WAVE TROUGH DIGGING ACROSS EASTERN GREAT LAKES AS H5 LOW TRYING TO CUT OFF AGAIN ACROSS HUDSON BAY. MAY SEE PERIODS OF WIDELY SCT SHOWERS FROM TIME TO TIME DURING THIS TIMEFRAME...BUT LOW CONFIDENCE ON TIMING AND PLACEMENT. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM /THROUGH WEDNESDAY NIGHT/... INTO THIS EVENING...HIGH CONFIDENCE. SCT SHRA/TSRA AROUND THE MA-CT-RI BORDER. SUB-SEVERE. TEMPO MVFR WITH +RA. SHOULD SEE THIS ACTIVITY DISSIPATE...BEGIN TO REFOCUS SE OFFSHORE AROUND NANTUCKET INTO THE OVERNIGHT HOURS ALONG AND AHEAD OF AN OUTFLOW PUSHING S. WINDS SHIFTING SW TO N WITH PASSAGE. TONIGHT...MODERATE CONFIDENCE. SHRA/TSRA LINGER OVER THE FAR SE TERMINALS TILL AROUND 6-9Z. TEMPO MVFR-IFR CONDITIONS FOCUSED TOWARDS THE CAPE / ISLANDS. OTHERWISE LIGHT WINDS AND VFR...THOUGH TERMINALS WHICH EXPERIENCED RAIN DURING THE DAY MAY SEE MVFR-LIFR PATCHY DENSE FOG. WEDNESDAY...HIGH CONFIDENCE. SCT SHRA WITH LOWER POSSIBILITY OF TSRA. LOW RISK OF SMALL HAIL. BREEZY W-WINDS WITH GUSTS UPWARDS OF 20 KTS. SCT-BKN LOW-END VFR CIGS. WEDNESDAY NIGHT...HIGH CONFIDENCE. W-WINDS DIMINISHING. VFR. SKC. LOW CONFIDENCE PATCHY DENSE FOG. KBOS TERMINAL...MODERATE CONFIDENCE. ENOUGH CONFIDENCE THAT STORMS WILL IMPACT THE TERMINAL WITH SIGNIFICANT IMPACT...BUT UNCERTAIN ON THE EXACT TIMING. KBDL TERMINAL...MODERATE CONFIDENCE. WATCHING CLOSELY FOR STORM IMPACT. STORMS COULD POTENTIALLY HOLD OFF TO THE N. OUTLOOK /THURSDAY THROUGH SUNDAY/... THURSDAY...HIGH CONFIDENCE. VFR. THURSDAY NIGHT THROUGH SATURDAY...LOW CONFIDENCE ON TIMING...HIGHER CONFIDENCE ON TRENDS. MVFR-IFR CONDITIONS IN AREAS OF RAIN SOMETIME DURING THIS PERIOD. VFR BEFORE AND AFTER PERIODS OF RAIN. SUNDAY...LOW CONFIDENCE MAINLY FOR TIMING. MAY SEE LEFTOVER SHOWERS WITH BRIEF MVFR CONDITIONS EARLY...THEN VFR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM /THROUGH TUESDAY NIGHT/... TONIGHT...MODERATE CONFIDENCE. SHOWERS AND THUNDERSTORMS LINGER OVER THE SE WATERS ALONG WITH BREEZY SW-WINDS. SUBSEQUENT 5-6 FOOT SEAS BEGINNING TO DIMINISH INTO MORNING AS THE WET-WEATHER AHEAD OF A FRONTAL BOUNDARY PUSHES OUT TO SEA BEHIND WHICH WINDS BACK W. WEDNESDAY...HIGH CONFIDENCE. W-WINDS CONTINUING PERHAPS BREEZY WITH GUSTS UPWARDS OF 20 KTS. SEAS WILL GRADUALLY DIMINISH THROUGH THE PERIOD. THERE IS THE POSSIBILITY OF SOME RENEWED SHOWER ACTIVITY THOUGH LIKELY CLOSER TO THE SHORE. WEDNESDAY NIGHT...HIGH CONFIDENCE. W-WINDS DIMINISHING ALLOWING SEAS TO RELAX. SHOULD SEE QUIET BOATING WEATHER. OUTLOOK /THURSDAY THROUGH SUNDAY/... THURSDAY-THURSDAY NIGHT...HIGH CONFIDENCE. WINDS AND SEAS BELOW SMALL CRAFT CRITERIA. LOCALLY REDUCED VSBYS IN LIGHT RAIN THU NIGHT. FRIDAY THROUGH SUNDAY...MODERATE CONFIDENCE. EASTERLY WINDS GUSTING UP TO 20 KT. WITH ONSHORE WINDS...SEAS LOOK TO BUILD UP TO 5-6 FT HIGHEST ACROSS THE EASTERN OUTER WATERS. RAIN LIKELY FRIDAY NIGHT THROUGH SATURDAY NIGHT...LIMITING VISIBILITIES AT TIMES...THEN SHOULD IMPROVE DURING SUNDAY. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ230>234-236-250-251. SMALL CRAFT ADVISORY UNTIL 8 AM EDT WEDNESDAY FOR ANZ235-237- 254>256. && $$ SYNOPSIS...SIPPRELL/EVT NEAR TERM...SIPPRELL SHORT TERM...SIPPRELL LONG TERM...EVT AVIATION...SIPPRELL/EVT MARINE...SIPPRELL/EVT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1103 AM EDT TUE AUG 4 2015 .SYNOPSIS... A SLOW MOVING COLD FRONT WILL APPROACH AND STALL ACROSS THE AREA THIS AFTERNOON. THE COLD FRONT MOVES OFFSHORE WEDNESDAY AS WEAK HIGH PRESSURE BUILDS INTO THE AREA. WEAK HIGH PRESSURE BUILDS INTO THE AREA ON THURSDAY. SEVERAL WAVES OF LOW PRESSURE MAY IMPACT THE AREA FRIDAY INTO SATURDAY. HIGH PRESSURE RETURNS FOR THE SECOND HALF OF THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... PNS IS FORTHCOMING WRT SVR TSTMS EARLY THIS MRNG. OTHERWISE...FCST REMAINS ON TRACK AS OF 11AM. STILL EXPECTING A MOSTLY DRY DAY...THOUGH POP UP CONVECTION IS EXPECTED THIS AFTERNOON. ISOLATED TSTMS DEVELOP IN RESPONSE TO HEATING THIS AFTERNOON AND THE FRONT BEING IN THE AREA. NCAR ENSEMBLE SUPPORTS ISOLATED CONVECTION AT BEST WITH FOCUS IN THE HUDSON VALLEY. HAVE KEPT POPS AT ISOLATED ALL LOCATIONS AS HRRR POPS SOME CONVECTION SOUTH OF THE ISLAND...THE CANADIAN HAS SOME OVER NYC AND NCEP HIRES ARW HAS SOME OVER LONG ISLAND. BLENDED MOS USED FOR TEMPS. HEAT INDICES GET INTO THE LOWER 90S IN THE NY/NJ METRO. THERE IS A HIGH RISK FOR THE DEVELOPMENT OF RIP CURRENTS AT THE OCEAN BEACHES TODAY. A RIP CURRENT STATEMENT IS IN EFFECT. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... FRONT MOVES SOUTH OF LONG ISLAND OVERNIGHT. DRY...LESS HUMID AND NEAR NORMAL FOR WEDNESDAY. BLENDED MOS USED FOR TEMPS. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... UPPER LEVEL TROUGH OVER THE REGION WEDNESDAY NIGHT LIFTS INTO SOUTHEAST CANADA ON THURSDAY WITH WEAK RIDGING AT THE SURFACE AND ALOFT. UPPER LEVEL VORTICITY/ENERGY CURRENTLY OVER THE ROCKIES WILL SLOWLY SLIDE EAST INTO THE OHIO VALLEY BY THURSDAY. THE STRENGTH OF THIS ENERGY WILL BE KEY TO THE DEVELOPMENT AND TRACK OF LOW PRESSURE ACROSS THE MID-ATLANTIC AND NORTHEAST THURSDAY NIGHT INTO SATURDAY. THE LATEST 00Z MODELS OFFER SLIGHTLY MORE CONFIDENCE THAT THERE WILL BE LOW PRESSURE IMPACTING THE AREA SOMETIME ON FRIDAY INTO AT LEAST THE FIRST PORTION OF SATURDAY. THE DETAILS ARE STILL VERY MUCH IN QUESTION...BUT A WIDESPREAD SIGNIFICANT RAINFALL IS POSSIBLE FRIDAY INTO SATURDAY MORNING. THE 00Z GFS IS THE FLATEST AND SLOWEST AS IT DOES NOT REALLY DEVELOP THE LOW UNTIL FRIDAY NIGHT AS A SECOND PIECE OF ENERGY AMPLIFIES BEHIND THE MAIN ONE. THE 00Z ECMWF IS THE STRONGEST WITH THIS ENERGY AND DEVELOPS THE LOW ACROSS THE MID ATLANTIC ON FRIDAY AND MOVES IT JUST SOUTH AND EAST OF LONG ISLAND INTO SATURDAY MORNING. THE 00Z GEFS ARE A BIT FASTER...WITH THE MEAN LOW TRACK AND TIMING SIMILAR TO THE 00Z ECMWF. HAVE CONTINUED WITH LIKELY POPS ON FRIDAY...AND HAVE INCREASED POPS TO LIKELY FRIDAY NIGHT. POPS THEN DECREASE TO CHANCE DURING THE DAY ON SATURDAY. AS TIMING BECOMES CLEARER...EXPECT ADJUSTMENTS TO THE TIMING OF POPS. THE LOW LIFTS NORTHEAST OF THE AREA SATURDAY NIGHT INTO SUNDAY MORNING WITH WEAK HIGH PRESSURE RETURNING ON SUNDAY WITH DRY CONDITIONS. TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW SEASONABLE LEVELS DURING THE PERIOD. FRIDAY AND SATURDAY WILL LIKELY BE THE COOLEST AS TEMPERATURES STRUGGLE TO GET OUT OF THE 70S. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... A COLD FRONT WILL MOVE EAST ACROSS THE AREA TONIGHT FOLLOWED BY HIGH PRESSURE ON WEDNESDAY. VFR WEATHER CONDITIONS WILL PREVAIL THROUGH WEDNESDAY. CHANCE OF ISOLATED TSTMS WITH STRONG WIND GUSTS...MAINLY EAST OF NYC THROUGH SUNSET. SEA BREEZES WILL INCREASE SW WINDS ARND 15 KT WITH GUSTS TO 25 KT FM 1 PM UNTIL SUNSET ACROSS ATLANTIC COASTAL TERMINALS INCLUDING KJFK. WINDS BECOME LIGHT AFT SUNSET THEN SHIFT FROM THE W ARND 10 KT ON WED. 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: TIMING OF WIND GUSTS MAY BE OFF BY +/- 1 HOUR. AMENDMENTS MAY BE NEEDED FOR ISOLATED CONVECTION THIS AFTERNOON. KLGA FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY +/- 1 HOUR. AMENDMENTS MAY BE NEEDED FOR ISOLATED CONVECTION THIS AFTERNOON. KEWR FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY +/- 1 HOUR. AMENDMENTS MAY BE NEEDED FOR ISOLATED CONVECTION THIS AFTERNOON. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY +/- 1 HOUR. AMENDMENTS MAY BE NEEDED FOR ISOLATED CONVECTION THIS AFTERNOON. KHPN FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY +/- 1 HOUR. AMENDMENTS MAY BE NEEDED FOR ISOLATED CONVECTION THIS AFTERNOON. KISP FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY +/- 1 HOUR. AMENDMENTS MAY BE NEEDED FOR ISOLATED CONVECTION THIS AFTERNOON. .OUTLOOK FOR 12Z WED THROUGH SAT... .WED-THU...VFR. GENERALLY W FLOW. .FRI...MVFR OR LOWER IN RAIN. WINDS BECOMING NE. .SAT...MVFR OR LOWER POSSIBLE IN RAIN. NE WINDS. && .MARINE... A SMALL CRAFT ADVISORY REMAINS IN EFFECT ON THE OCEAN WATERS THROUGH EARLY THIS EVENING DUE TO ELEVATED SEAS AND WINDS INCREASING THIS AFTERNOON. OCEAN SEAS WILL BE SUBSIDING TONIGHT...BUT 5 FT SEAS MAY LINGER ON THE EASTERN OCEAN UNTIL WEDNESDAY MORNING. WEAK HIGH PRESSURE PASSES OVER THE WATERS ON WEDNESDAY WITH SUB SCA CONDITIONS EXPECTED. SEVERAL WAVES OF LOW PRESSURE MAY PASS OVER THE WATERS FOR THE END OF THE WEEK. OCCASIONAL SCA CONDITIONS ARE POSSIBLE ON FRIDAY...ESPECIALLY ON THE OCEAN. WEAK HIGH PRESSURE WILL MOVE OVER THE WATERS ON THURSDAY WITH LOW PRESSURE ON FRIDAY INTO SATURDAY. SUB SCA CONDITIONS ARE EXPECTED THURSDAY INTO FRIDAY...WITH SEAS BUILDING TO AROUND 5 FT ON SATURDAY ON THE OCEAN. && .HYDROLOGY... ORGANIZED SIGNIFICANT RAINFALL IS NOT EXPECTED THROUGH THURSDAY. A WIDESPREAD SIGNIFICANT RAINFALL IS POSSIBLE FRIDAY INTO SATURDAY. HOWEVER...UNCERTAINTY EXISTS IN WHERE AND WHEN THE HEAVIEST OF THE RAIN WILL FALL. ANTECEDENT DRY CONDITIONS SHOULD LIMIT FLOODING POTENTIAL. HOWEVER...ANY HEAVIER RAINFALL THAT DO DEVELOPS WOULD HAVE THE POTENTIAL FOR LOCALIZED FLOODING. && .EQUIPMENT... TEWR TERMINAL DOPPLER RADAR REMAINS UNAVAILABLE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH RIP CURRENT RISK UNTIL 9 PM EDT THIS EVENING FOR NYZ075- 080-081-178-179. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ350- 353-355. && $$ SYNOPSIS...TONGUE NEAR TERM...TONGUE/JMC SHORT TERM...TONGUE LONG TERM...DS AVIATION...GC MARINE...TONGUE HYDROLOGY...TONGUE EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
745 AM EDT TUE AUG 4 2015 .SYNOPSIS... A SLOW MOVING COLD FRONT WILL APPROACH AND STALL ACROSS THE AREA THIS AFTERNOON. THE COLD FRONT MOVES OFFSHORE WEDNESDAY AS WEAK HIGH PRESSURE BUILDS INTO THE AREA. WEAK HIGH PRESSURE BUILDS INTO THE AREA ON THURSDAY. SEVERAL WAVES OF LOW PRESSURE MAY IMPACT THE AREA FRIDAY INTO SATURDAY. HIGH PRESSURE RETURNS FOR THE SECOND HALF OF THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... EXPECTING A MOSTLY DRY DAY...THOUGH POP UP CONVECTION IS EXPECTED THIS AFTERNOON. ISOLATED TSTMS DEVELOP IN RESPONSE TO HEATING THIS AFTERNOON AND THE FRONT BEING IN THE AREA. NCAR ENSEMBLE SUPPORTS ISOLATED CONVECTION AT BEST WITH FOCUS IN THE HUDSON VALLEY. HAVE KEPT POPS AT ISOLATED ALL LOCATIONS AS HRRR POPS SOME CONVECTION SOUTH OF THE ISLAND...THE CANADIAN HAS SOME OVER NYC AND NCEP HIRES ARW HAS SOME OVER LONG ISLAND. BLENDED MOS USED FOR TEMPS. HEAT INDICES GET INTO THE LOWER 90S IN THE NY/NJ METRO. THERE IS A HIGH RISK FOR THE DEVELOPMENT OF RIP CURRENTS AT THE OCEAN BEACHES TODAY. A RIP CURRENT STATEMENT IS IN EFFECT. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... FRONT MOVES SOUTH OF LONG ISLAND OVERNIGHT. DRY...LESS HUMID AND NEAR NORMAL FOR WEDNESDAY. BLENDED MOS USED FOR TEMPS. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... UPPER LEVEL TROUGH OVER THE REGION WEDNESDAY NIGHT LIFTS INTO SOUTHEAST CANADA ON THURSDAY WITH WEAK RIDGING AT THE SURFACE AND ALOFT. UPPER LEVEL VORTICITY/ENERGY CURRENTLY OVER THE ROCKIES WILL SLOWLY SLIDE EAST INTO THE OHIO VALLEY BY THURSDAY. THE STRENGTH OF THIS ENERGY WILL BE KEY TO THE DEVELOPMENT AND TRACK OF LOW PRESSURE ACROSS THE MID-ATLANTIC AND NORTHEAST THURSDAY NIGHT INTO SATURDAY. THE LATEST 00Z MODELS OFFER SLIGHTLY MORE CONFIDENCE THAT THERE WILL BE LOW PRESSURE IMPACTING THE AREA SOMETIME ON FRIDAY INTO AT LEAST THE FIRST PORTION OF SATURDAY. THE DETAILS ARE STILL VERY MUCH IN QUESTION...BUT A WIDESPREAD SIGNIFICANT RAINFALL IS POSSIBLE FRIDAY INTO SATURDAY MORNING. THE 00Z GFS IS THE FLATEST AND SLOWEST AS IT DOES NOT REALLY DEVELOP THE LOW UNTIL FRIDAY NIGHT AS A SECOND PIECE OF ENERGY AMPLIFIES BEHIND THE MAIN ONE. THE 00Z ECMWF IS THE STRONGEST WITH THIS ENERGY AND DEVELOPS THE LOW ACROSS THE MID ATLANTIC ON FRIDAY AND MOVES IT JUST SOUTH AND EAST OF LONG ISLAND INTO SATURDAY MORNING. THE 00Z GEFS ARE A BIT FASTER...WITH THE MEAN LOW TRACK AND TIMING SIMILAR TO THE 00Z ECMWF. HAVE CONTINUED WITH LIKELY POPS ON FRIDAY...AND HAVE INCREASED POPS TO LIKELY FRIDAY NIGHT. POPS THEN DECREASE TO CHANCE DURING THE DAY ON SATURDAY. AS TIMING BECOMES CLEARER...EXPECT ADJUSTMENTS TO THE TIMING OF POPS. THE LOW LIFTS NORTHEAST OF THE AREA SATURDAY NIGHT INTO SUNDAY MORNING WITH WEAK HIGH PRESSURE RETURNING ON SUNDAY WITH DRY CONDITIONS. TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW SEASONABLE LEVELS DURING THE PERIOD. FRIDAY AND SATURDAY WILL LIKELY BE THE COOLEST AS TEMPERATURES STRUGGLE TO GET OUT OF THE 70S. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... A COLD FRONT CONTINUES TO SLOWLY APPROACH FROM THE WEST. MOST OF THE SHOWERS AND THUNDERSTORMS HAVE NOW COME TO AN END ACROSS THE REGION. GENERALLY EXPECTING VFR CONDITIONS THROUGH THE TAF PERIOD. ADDITIONAL ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE LATE IN THE AFTERNOON...MAINLY AFTER 18Z...BUT WILL LEAVE OUT OF THE TAF FOR NOW WITH LOW CONFIDENCE OF COVERAGE AND TIMING. SOUTHWEST WINDS OF 5-10 KT INCREASE TO 8-12 KT. THE GRADIENT TIGHTENS THIS AFTERNOON...WITH LOCAL SEA BREEZES AT COASTAL TERMINALS. EXPECT GUSTS INTO THE LOWER AND MIDDLE 20 KT RANGE. WINDS DIMINISH THIS EVENING TO 10 KT OR LESS. TERMINALS OUTSIDE OF NYC...MAY BECOME LIGHT AND VARIABLE. 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: AFTERNOON SEABREEZES LIKELY TODAY. TIMING OF GUSTS MAY BE OFF BY +/- 1 HOUR TODAY. AMENDMENTS MAY BE NEEDED FOR ANY ISOLATED CONVECTION THIS AFTERNOON. KLGA FCSTER COMMENTS: TIMING OF GUSTS MAY BE OFF BY +/- 1 HOUR TODAY. AMENDMENTS MAY BE NEEDED FOR ANY ISOLATED CONVECTION THIS AFTERNOON. KEWR FCSTER COMMENTS: TIMING OF GUSTS MAY BE OFF BY +/- 1 HOUR TODAY. AMENDMENTS MAY BE NEEDED FOR ANY ISOLATED CONVECTION THIS AFTERNOON. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: TIMING OF GUSTS MAY BE OFF BY +/- 1 HOUR TODAY. AMENDMENTS MAY BE NEEDED FOR ANY ISOLATED CONVECTION THIS AFTERNOON. KHPN FCSTER COMMENTS: TIMING OF GUSTS MAY BE OFF BY +/- 1 HOUR TODAY. AMENDMENTS MAY BE NEEDED FOR ANY ISOLATED CONVECTION THIS AFTERNOON. KISP FCSTER COMMENTS: AFTERNOON SEABREEZES LIKELY TODAY. TIMING OF GUSTS MAY BE OFF BY +/- 1 HOUR TODAY. AMENDMENTS MAY BE NEEDED FOR ANY ISOLATED CONVECTION THIS AFTERNOON. .OUTLOOK FOR 12Z WED THROUGH SAT... .WED-THU...VFR. GENERALLY W FLOW. .FRI...MVFR OR LOWER IN RAIN. WINDS BECOMING NE. .SAT...MVFR OR LOWER POSSIBLE IN RAIN. NE WINDS. && .MARINE... A SMALL CRAFT ADVISORY REMAINS IN EFFECT ON THE OCEAN WATERS THROUGH EARLY THIS EVENING DUE TO ELEVATED SEAS AND WINDS INCREASING THIS AFTERNOON. OCEAN SEAS WILL BE SUBSIDING TONIGHT...BUT 5 FT SEAS MAY LINGER ON THE EASTERN OCEAN UNTIL WEDNESDAY MORNING. WEAK HIGH PRESSURE PASSES OVER THE WATERS ON WEDNESDAY WITH SUB SCA CONDITIONS EXPECTED. SEVERAL WAVES OF LOW PRESSURE MAY PASS OVER THE WATERS FOR THE END OF THE WEEK. OCCASIONAL SCA CONDITIONS ARE POSSIBLE ON FRIDAY...ESPECIALLY ON THE OCEAN. WEAK HIGH PRESSURE WILL MOVE OVER THE WATERS ON THURSDAY WITH LOW PRESSURE ON FRIDAY INTO SATURDAY. SUB SCA CONDITIONS ARE EXPECTED THURSDAY INTO FRIDAY...WITH SEAS BUILDING TO AROUND 5 FT ON SATURDAY ON THE OCEAN. && .HYDROLOGY... ORGANIZED SIGNIFICANT RAINFALL IS NOT EXPECTED THROUGH THURSDAY. A WIDESPREAD SIGNIFICANT RAINFALL IS POSSIBLE FRIDAY INTO SATURDAY. HOWEVER...UNCERTAINTY EXISTS IN WHERE AND WHEN THE HEAVIEST OF THE RAIN WILL FALL. ANTECEDENT DRY CONDITIONS SHOULD LIMIT FLOODING POTENTIAL. HOWEVER...ANY HEAVIER RAINFALL THAT DO DEVELOPS WOULD HAVE THE POTENTIAL FOR LOCALIZED FLOODING. && .EQUIPMENT... TEWR TERMINAL DOPPLER RADAR REMAINS UNAVAILABLE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR NYZ075-080-081- 178-179. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ350- 353-355. && $$ SYNOPSIS...TONGUE NEAR TERM...TONGUE SHORT TERM...TONGUE LONG TERM...DS AVIATION...BC MARINE...TONGUE HYDROLOGY...TONGUE EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
310 AM EDT TUE AUG 4 2015 .SYNOPSIS... A SLOW MOVING COLD FRONT WILL APPROACH OVERNIGHT THEN STALL ACROSS THE AREA TODAY. THE COLD FRONT MOVES OFFSHORE WEDNESDAY AS WEAK HIGH PRESSURE BUILDS INTO THE AREA. SEVERAL WAVES OF LOW PRESSURE MAY IMPACT THE AREA FOR THE END OF THE WEEK. HIGH PRESSURE BUILDS BACK IN FOR THE WEEKEND. && .NEAR TERM /UNTIL 9 AM THIS MORNING/... TWO RATHER DIFFUSE FRONTS APPROACHING FROM THE NW. THE FIRST FRONT IS FORCING CONVECTION AHEAD OF IT IS BEING MAINTAINED BY BOTH THERMODYNAMICS IN THE FORM OF HIGH CAPE AND DYNAMICS IN THE FORM OF A PRONOUNCED JET STREAK. INSTABILITY IS RATHER IMPRESSIVE. COMPARING LATEST KEWR ACARS SOUNDING WITH RAP SUPPORTS LI`S ON -2 C AND THE 60KT JET ENTRANCE WINDS. RAP SOUNDINGS INDICATES CONTINUED DESTABILIZATION THE NEXT FEW HOURS WITH AREAS TO THE EAST (CT AND LONG ISLAND) BECOMING VERY UNSTABLE. FOR EXAMPLE...KISP HAS 3000 J/KG OF CAPE AND -6 C ON THE LI`S. THUS AM FCSTING THE LINE THAT`S FORMING ALONG THE DELAWARE TO CONTINUE AND GROW. HAVE ADDED GUSTY WINDS AND HEAVY RAIN TO THE TSTM DESCRIPTORS. WILL HAVE TO WATCH THIS CLOSELY SEVERE AND QUICK SPIN UPS. HAVE INCREASED POPS FOR CT AND LONG ISLAND. EXPECT THE ACTIVITY IS EAST OF CT AND LONG ISLAND BY 930 AM. IT LOOKS LIKE MUCH OF THE ACTIVITY BEHIND THE EASTERN PA CLUSTER WILL WEAKEN - BUT CONFIDENCE IN THIS OCCURRING REMAINS LOW. && .SHORT TERM /9 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... THE FRONT STALLS ACROSS THE AREA TODAY WITH A SLIGHT CHANCE OF AFTERNOON SHOWERS AND THUNDERSTORMS. VERY LITTLE APPRECIABLE DIFFERENCE WILL BE FELT WITH TEMPERATURES REMAINING ABOVE NORMAL AND SIMILAR HUMIDITY AS MONDAY. LATE TONIGHT THE UPPER TROUGH BUILDS FARTHER SOUTH AND EAST...FORCING THE ATTENDANT SURFACE FRONT FARTHER OFFSHORE WITH LOWER DEW POINTS ADVECTING INTO THE REGION. A SUBSEQUENT DECREASE IN HUMIDITY WILL BE FELT AS THIS OCCURS. THERE IS A HIGH RISK FOR THE DEVELOPMENT OF RIP CURRENTS AT THE OCEAN BEACHES TODAY. A RIP CURRENT STATEMENT IS IN EFFECT. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... COLD FRONT CONTINUES TO SLOWLY MOVE OFFSHORE WITH HIGH PRESSURE BUILDING INTO THE AREA ON WEDNESDAY. UPPER LEVEL TROUGH REMAINS OVER THE AREA INTO THURSDAY. UPPER LEVEL TROUGH DEPARTS THE AREA WEDNESDAY NIGHT INTO THURSDAY. MODELS HAVE COME INTO BETTER AGREEMENT WITH SURFACE LOW OVER THE MID- WEST TREKKING EAST WEDNESDAY NIGHT AND AFFECTING THE AREA MAINLY FROM THURSDAY NIGHT THROUGH AT LEAST FRIDAY NIGHT. HOWEVER...THERE IS STILL UNCERTAINTY ON WHERE IT TRACKS AND THEREFORE HOW MUCH RAIN WE DO RECEIVE. HOWEVER...IT DOES APPEAR MORE CERTAIN THAT A WIDESPREAD HEAVY RAIN EVENT IS IN STORE FOR THIS TIME PERIOD. ISENTROPIC LIFT OUT AHEAD OF THE APPROACHING LOW NOTED IN BOTH THE 12Z GFS AND 12Z ECMWF...MAINLY LATE THURSDAY NIGHT...SO THINKING THIS WILL BE MORE STRATIFORM RAIN. SURFACE LOW CONTINUES ITS APPROACH FRIDAY MORNING. MODELS DIFFER IN THE PLACEMENT OF THE LOW. THE 12Z ECMWF AND 12Z GFS AGREE WITH THE LOW BEING OVER THE NORTHERN MID-ATLANTIC STATES BY 06Z SATURDAY. THEREAFTER...MODELS DIFFER QUITE A BIT IN THEIR SOLUTIONS. 12Z ECMWF TREKS THE LOW NORTHEAST IN SIDE THE 40/70 BENCHMARK THROUGH THE DAY SATURDAY WHILE IT SLOWLY STRENGTHENS WHILE THE GFS WEAKENS THE LOW OVER THE OLD FRONTAL BOUNDARY OFFSHORE AND WEAKER WAVES OF LOW PRESSURE RIDING ALONG IT...WHILE THE 12Z CANADIAN IS AN OUTLIER BEING MORE PROGRESSIVE THAN THE OTHER MODELS. THEREFORE...SIDED MORE ALONG THE LINES OF THE GFS AND ECMWF AND KEEP CHANCE POPS IN THE AREA THROUGH THE DAY SATURDAY LOW PRESSURE PUSHES AWAY FROM THE AREA LATE SATURDAY NIGHT INTO SUNDAY AS WEAK HIGH PRESSURE BUILDS BACK INTO THE REGION FOR THE SECOND HALF OF THE WEEKEND WITH A RETURN TO DRY CONDITIONS. OUTSIDE OF FRIDAY...TEMPERATURES SHOULD BE SEASONABLE FOR THIS TIME OF YEAR. RAIN AND CLOUDS WILL KEEP TEMPERATURES DOWN ON FRIDAY...NOT MAKING IT OUT OF THE 70S REGION-WIDE. IN FACT...TEMPERATURES MAY PROVE TO BE A BIT LOWER THAN WHAT IS CURRENTLY FORECAST. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... A COLD FRONT CONTINUES TO SLOWLY APPROACH FROM THE WEST. ARE WATCHING AREAS OF CONVECTION OFF TO THE WEST. THESE STORMS SHOULD APPROACH THE NYC METRO AROUND 09Z. WILL CONTINUE TO KEEP TEMPOS IN TO ACCOUNT FOR THIS. HAVE LEFT OUT OF TERMINALS EAST OF NYC WITH LOWER CONFIDENCE OF ANY THUNDER REACHING THOSE TERMINALS. AMENDMENTS ARE LIKELY THIS MORNING TO ACCOUNT FOR CONVECTION TIMING. EXPECT S-SW WINDS OF 5-10 KT AT KNYC TERMINALS AND 5 KT OR LESS INLAND OVERNIGHT ALONG WITH MAINLY VFR CONDITIONS. SOME IFR CIGS ARE LIKELY FROM KISP AND POINTS EAST FOR LOW STRATUS. AFTER FRONTAL PASSAGE...WINDS SHIFT TO THE W-SW AND INCREASE TO 8-12 KT. GRADIENT TIGHTENS THIS AFTERNOON. LOCAL SEA BREEZES POSSIBLE AT COASTAL TERMINALS. SCT SHRA/TSRA POSSIBLE LATE IN THE AFTERNOON. .OUTLOOK FOR 06Z WED THROUGH SAT... .TUE NIGHT...SLGT CHC FOR TSTMS MAINLY CSTL TERMINALS IN THE EVENING. BECOMING VFR OVERNIGHT. SW FLOW BECOMING NW OVERNIGHT. .WED-THU...VFR. GENERALLY W FLOW. .FRI...MVFR OR LOWER IN RAIN. WINDS BECOMING NE. .SAT...MVFR OR LOWER POSSIBLE IN RAIN. NE WINDS. && .MARINE... FORECAST ON TRACK...NO UPDATES AT THIS TIME. WINDS OUT AHEAD OF THE FRONT WILL REMAIN STRONG INTO LATE TONIGHT BEFORE LIGHTENING WITH THE APPROACH OF THE FRONT. OCEAN SEAS BUILD DUE TO THE INCREASE IN THESE WINDS. A SMALL CRAFT ADVISORY REMAINS IN EFFECT ON THE OCEAN WATERS THROUGH EARLY TUESDAY EVENING. OCEAN SEAS WILL BE SUBSIDING TUESDAY NIGHT...BUT 5 FT SEAS MAY LINGER ON THE EASTERN OCEAN UNTIL WEDNESDAY MORNING. WEAK HIGH PRESSURE PASSES OVER THE WATERS ON WEDNESDAY WITH SUB SCA CONDITIONS EXPECTED. SEVERAL WAVES OF LOW PRESSURE MAY PASS OVER THE WATERS FOR THE END OF THE WEEK. OCCASIONAL SCA CONDITIONS ARE POSSIBLE ON FRIDAY...ESPECIALLY ON THE OCEAN. WEAK HIGH PRESSURE PASSES OVER THE WATERS ON WEDNESDAY WITH SUB SCA CONDITIONS EXPECTED. LOW PRESSURE MAY PASS OVER OR NEAR THE WATERS FOR THE END OF THE WEEK INTO THE FIRST HALF OF THE WEEKEND. OCCASIONAL SCA CONDITIONS ARE POSSIBLE ON SATURDAY...ESPECIALLY ON THE OCEAN. && .HYDROLOGY... A TENTH TO A QUARTER INCH OF BASIN AVERAGE RAINFALL THIS MORNING. LOCALLY HIGHER AMOUNTS ARE POSSIBLE IN ANY HEAVIER THUNDERSTORMS. A WIDESPREAD SIGNIFICANT RAINFALL IS POSSIBLE LATE THURSDAY INTO FRIDAY. HOWEVER...UNCERTAINTY EXISTS IN WHERE AND WHEN THE HEAVIEST OF THE RAIN WILL FALL. ANTECEDENT DRY CONDITIONS SHOULD LIMIT FLOODING POTENTIAL. HOWEVER...ANY THUNDERSTORMS THAT DO DEVELOP WOULD HAVE THE POTENTIAL FOR LOCALIZED FLOODING. && .EQUIPMENT... TEWR TERMINAL DOPPLER RADAR REMAINS UNAVAILABLE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH RIP CURRENT RISK FROM 6 AM EDT THIS MORNING THROUGH THIS EVENING FOR NYZ075-080-081-178-179. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ350- 353-355. && $$ SYNOPSIS...TONGUE NEAR TERM...TONGUE SHORT TERM...TONGUE LONG TERM...JP AVIATION...BC MARINE...TONGUE HYDROLOGY...TONGUE EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
201 AM EDT TUE AUG 4 2015 .SYNOPSIS... A SLOW MOVING COLD FRONT WILL APPROACH OVERNIGHT THEN STALL ACROSS THE AREA TODAY. THE COLD FRONT MOVES OFFSHORE WEDNESDAY AS WEAK HIGH PRESSURE BUILDS INTO THE AREA. SEVERAL WAVES OF LOW PRESSURE MAY IMPACT THE AREA FOR THE END OF THE WEEK. HIGH PRESSURE BUILDS BACK IN FOR THE WEEKEND. && .NEAR TERM /UNTIL 9 AM THIS MORNING/... IT APPEARS TO ME LIKE WE HAVE TWO FRONTS...BOTH RATHER DIFFUSE. THE FIRST FRONT IS FORCING CONVECTION AHEAD OF IT. THIS CONVECTION WILL LIKELY REACH THE NY METRO BEFORE SUNRISE. HAVE RAISED POPS TO LIKELY THERE. THE QUESTION IS WHAT HAPPENS WITH THE ACTIVITY BEHIND THE INITIAL CLUSTER AND WILL THE INITIAL CLUSTER SURVIVE INTO CT? RAP AND HRRR DO NOT HAVE A GOOD HANDLE ON THIS DEVELOPING PCPN. NARRE-TL SEEMS TO HAVE A BETTER COMPOSITE OF THE TREND THAT SUGGESTS THE ACTIVITY CONTINUES AND INCREASES AS IT MOVES INTO CT FOR THE EARLY MORNING RUSH. KEEPING THE SCT COVERAGE FOR THIS BETWEEN 6 AND 9 AM LOCAL. IT LOOKS LIKE MUCH OF THE ACTIVITY BEHIND THE EASTERN PA CLUSTER WILL WEAKEN - BUT CONFIDENCE IN THIS OCCURRING REMAINS LOW. EXPECT ADDITIONAL REVISIONS AS THE CONVECTION EVOLVE EARLY THIS MORNING. && .SHORT TERM /9 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... THE FRONT STALLS ACROSS THE AREA TODAY WITH A SLIGHT CHANCE OF AFTERNOON SHOWERS AND THUNDERSTORMS. VERY LITTLE APPRECIABLE DIFFERENCE WILL BE FELT WITH TEMPERATURES REMAINING ABOVE NORMAL AND SIMILAR HUMIDITY AS MONDAY. LATE TONIGHT THE UPPER TROUGH BUILDS FARTHER SOUTH AND EAST...FORCING THE ATTENDANT SURFACE FRONT FARTHER OFFSHORE WITH LOWER DEW POINTS ADVECTING INTO THE REGION. A SUBSEQUENT DECREASE IN HUMIDITY WILL BE FELT AS THIS OCCURS. THERE IS A HIGH RISK FOR THE DEVELOPMENT OF RIP CURRENTS AT THE OCEAN BEACHES TODAY. A RIP CURRENT STATEMENT IS IN EFFECT. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... COLD FRONT CONTINUES TO SLOWLY MOVE OFFSHORE WITH HIGH PRESSURE BUILDING INTO THE AREA ON WEDNESDAY. UPPER LEVEL TROUGH REMAINS OVER THE AREA INTO THURSDAY. UPPER LEVEL TROUGH DEPARTS THE AREA WEDNESDAY NIGHT INTO THURSDAY. MODELS HAVE COME INTO BETTER AGREEMENT WITH SURFACE LOW OVER THE MID- WEST TREKKING EAST WEDNESDAY NIGHT AND AFFECTING THE AREA MAINLY FROM THURSDAY NIGHT THROUGH AT LEAST FRIDAY NIGHT. HOWEVER...THERE IS STILL UNCERTAINTY ON WHERE IT TRACKS AND THEREFORE HOW MUCH RAIN WE DO RECEIVE. HOWEVER...IT DOES APPEAR MORE CERTAIN THAT A WIDESPREAD HEAVY RAIN EVENT IS IN STORE FOR THIS TIME PERIOD. ISENTROPIC LIFT OUT AHEAD OF THE APPROACHING LOW NOTED IN BOTH THE 12Z GFS AND 12Z ECMWF...MAINLY LATE THURSDAY NIGHT...SO THINKING THIS WILL BE MORE STRATIFORM RAIN. SURFACE LOW CONTINUES ITS APPROACH FRIDAY MORNING. MODELS DIFFER IN THE PLACEMENT OF THE LOW. THE 12Z ECMWF AND 12Z GFS AGREE WITH THE LOW BEING OVER THE NORTHERN MID-ATLANTIC STATES BY 06Z SATURDAY. THEREAFTER...MODELS DIFFER QUITE A BIT IN THEIR SOLUTIONS. 12Z ECMWF TREKS THE LOW NORTHEAST IN SIDE THE 40/70 BENCHMARK THROUGH THE DAY SATURDAY WHILE IT SLOWLY STRENGTHENS WHILE THE GFS WEAKENS THE LOW OVER THE OLD FRONTAL BOUNDARY OFFSHORE AND WEAKER WAVES OF LOW PRESSURE RIDING ALONG IT...WHILE THE 12Z CANADIAN IS AN OUTLIER BEING MORE PROGRESSIVE THAN THE OTHER MODELS. THEREFORE...SIDED MORE ALONG THE LINES OF THE GFS AND ECMWF AND KEEP CHANCE POPS IN THE AREA THROUGH THE DAY SATURDAY LOW PRESSURE PUSHES AWAY FROM THE AREA LATE SATURDAY NIGHT INTO SUNDAY AS WEAK HIGH PRESSURE BUILDS BACK INTO THE REGION FOR THE SECOND HALF OF THE WEEKEND WITH A RETURN TO DRY CONDITIONS. OUTSIDE OF FRIDAY...TEMPERATURES SHOULD BE SEASONABLE FOR THIS TIME OF YEAR. RAIN AND CLOUDS WILL KEEP TEMPERATURES DOWN ON FRIDAY...NOT MAKING IT OUT OF THE 70S REGION-WIDE. IN FACT...TEMPERATURES MAY PROVE TO BE A BIT LOWER THAN WHAT IS CURRENTLY FORECAST. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... A COLD FRONT CONTINUES TO SLOWLY APPROACH FROM THE WEST. ARE WATCHING AREAS OF CONVECTION OFF TO THE WEST. THESE STORMS SHOULD APPROACH THE NYC METRO AROUND 09Z. WILL CONTINUE TO KEEP TEMPOS IN TO ACCOUNT FOR THIS. HAVE LEFT OUT OF TERMINALS EAST OF NYC WITH LOWER CONFIDENCE OF ANY THUNDER REACHING THOSE TERMINALS. AMENDMENTS ARE LIKELY THIS MORNING TO ACCOUNT FOR CONVECTION TIMING. EXPECT S-SW WINDS OF 5-10 KT AT KNYC TERMINALS AND 5 KT OR LESS INLAND OVERNIGHT ALONG WITH MAINLY VFR CONDITIONS. SOME IFR CIGS ARE LIKELY FROM KISP AND POINTS EAST FOR LOW STRATUS. AFTER FRONTAL PASSAGE...WINDS SHIFT TO THE W-SW AND INCREASE TO 8-12 KT. GRADIENT TIGHTENS THIS AFTERNOON. LOCAL SEA BREEZES POSSIBLE AT COASTAL TERMINALS. SCT SHRA/TSRA POSSIBLE LATE IN THE AFTERNOON. .OUTLOOK FOR 06Z WED THROUGH SAT... .TUE NIGHT...SLGT CHC FOR TSTMS MAINLY CSTL TERMINALS IN THE EVENING. BECOMING VFR OVERNIGHT. SW FLOW BECOMING NW OVERNIGHT. .WED-THU...VFR. GENERALLY W FLOW. .FRI...MVFR OR LOWER IN RAIN. WINDS BECOMING NE. .SAT...MVFR OR LOWER POSSIBLE IN RAIN. NE WINDS. && .MARINE... FORECAST ON TRACK...NO UPDATES AT THIS TIME. WINDS OUT AHEAD OF THE FRONT WILL REMAIN STRONG INTO LATE TONIGHT BEFORE LIGHTENING WITH THE APPROACH OF THE FRONT. OCEAN SEAS BUILD DUE TO THE INCREASE IN THESE WINDS. A SMALL CRAFT ADVISORY REMAINS IN EFFECT ON THE OCEAN WATERS THROUGH EARLY TUESDAY EVENING. OCEAN SEAS WILL BE SUBSIDING TUESDAY NIGHT...BUT 5 FT SEAS MAY LINGER ON THE EASTERN OCEAN UNTIL WEDNESDAY MORNING. WEAK HIGH PRESSURE PASSES OVER THE WATERS ON WEDNESDAY WITH SUB SCA CONDITIONS EXPECTED. SEVERAL WAVES OF LOW PRESSURE MAY PASS OVER THE WATERS FOR THE END OF THE WEEK. OCCASIONAL SCA CONDITIONS ARE POSSIBLE ON FRIDAY...ESPECIALLY ON THE OCEAN. WEAK HIGH PRESSURE PASSES OVER THE WATERS ON WEDNESDAY WITH SUB SCA CONDITIONS EXPECTED. LOW PRESSURE MAY PASS OVER OR NEAR THE WATERS FOR THE END OF THE WEEK INTO THE FIRST HALF OF THE WEEKEND. OCCASIONAL SCA CONDITIONS ARE POSSIBLE ON SATURDAY...ESPECIALLY ON THE OCEAN. && .HYDROLOGY... A TENTH TO A QUARTER INCH OF BASIN AVERAGE RAINFALL THIS MORNING. LOCALLY HIGHER AMOUNTS ARE POSSIBLE IN ANY HEAVIER THUNDERSTORMS. A WIDESPREAD SIGNIFICANT RAINFALL IS POSSIBLE LATE THURSDAY INTO FRIDAY. HOWEVER...UNCERTAINTY EXISTS IN WHERE AND WHEN THE HEAVIEST OF THE RAIN WILL FALL. ANTECEDENT DRY CONDITIONS SHOULD LIMIT FLOODING POTENTIAL. HOWEVER...ANY THUNDERSTORMS THAT DO DEVELOP WOULD HAVE THE POTENTIAL FOR LOCALIZED FLOODING. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH RIP CURRENT RISK FROM 6 AM EDT THIS MORNING THROUGH THIS EVENING FOR NYZ075-080-081-178-179. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ350- 353-355. && $$ SYNOPSIS...MD/JP NEAR TERM...MET/TONGUE SHORT TERM...MD LONG TERM...JP AVIATION...BC/MPS MARINE...MET HYDROLOGY...MD/JP
AREA FORECAST DISCUSSION
NWS LINCOLN IL
600 PM CDT TUE AUG 4 2015 .SHORT TERM...(TONIGHT) ISSUED AT 303 PM CDT TUE AUG 4 2015 A STATIONARY FRONTAL BOUNDARY WILL LINGER ACROSS SOUTHERN IL TONIGHT, WHERE BETTER CHANCES OF SHOWERS AND STORMS SHOULD START OUT THE EVENING. NORTH OF THE BOUNDARY INTO OUR SOUTHERN COUNTIES, WEAK ISENTROPIC LIFT AND MID LEVEL CONVERGENCE WILL WORK TO TRIGGER SHOWERS AND A FEW STORMS TOWARD SPRINGFIELD TO MATTOON TONIGHT. THIS AFTERNOON, SHOWERS/STORMS DEVELOPED WELL NORTH OF WHERE THE HRRR AND RAP MODELS INDICATED, SO THE FACT THAT THEY CONTINUE TO SHOW DRY CONDITIONS OVERNIGHT FOR OUR COUNTIES DOES NOT PRECLUDE THAT SHOWERS REACH AS FAR NORTH AS LINCOLN TO MATTOON AGAIN OVERNIGHT. ONGOING SHOWERS/STORMS LATE THIS AFTERNOON FROM SPRINGFIELD TO SHELBYVILLE ARE EXPECTED TO DISSIPATE AS THEY PROGRESS EASTWARD. THEREFORE WILL START OUT THE EVENING GRIDS WILL MAINLY SLIGHT CHANCE IN OUR SOUTHERN COUNTIES, BUT MAY ADJUST POPS UP AS LATE AFTERNOON CONDITIONS WARRANT. DESPITE THE DRY HIGH RESOLUTION MODELS TONIGHT, THE CONSENSUS OF THE GFS, NAM, ECMWF AND CANADIAN INDICATES ENOUGH FORCING FOR PRECIP REDEVELOPING ACROSS OUR SOUTHERN COUNTIES. THEREFORE, HAVE NOT STRAYED FAR FROM THE CURRENT FORECAST OF CHANCE POPS EXPANDING NORTH TO AREAS SOUTHWEST OF A LINE FROM CANTON TO LINCOLN TO MATTOON. LOW TEMPS TONIGHT WILL VARY BASED ON THE AMOUNT OF CLEARING THAT DEVELOPS UNDER LIGHT ENE FLOW. AFTERNOON DEWPOINTS HAVE POINTED TOWARD LOWS TONIGHT GENERALLY IN THE LOWER 60S NORTH OF I-74, WITH UPPER 60S IN SOUTH OF I-70, WHERE CLOUDS MAY BE MORE PREVALENT LATER TONIGHT. .LONG TERM...(WEDNESDAY THROUGH TUESDAY) ISSUED AT 303 PM CDT TUE AUG 4 2015 WEDNESDAY COULD START OUT WILL A LULL IN THE SHOWERS AS THE ENERGY FROM THE OVERNIGHT CONVECTION SHIFTS EAST INTO INDIANA. THE NEXT WAVE OF PRECIP LOOKS TO BE TIED TO THE ADVANCEMENT OF A LOW PRESSURE SYSTEM FROM THE CENTRAL PLAINS ACROSS SOUTH CENTRAL IL. THE 12Z MODELS HAVE CONTINUED WITH THE SOUTHWARD TREND OF TRACKING THE LOW ACROSS IL WEDNESDAY NIGHT INTO THURSDAY. HOWEVER, THEY ALSO CONTINUE TO PROJECT OVERRUNNING SHOWERS/STORMS DEVELOPING AHEAD OF THE LOW WED AFTERNOON ACROSS OUR SOUTHERN COUNTIES. WEDNESDAY NIGHT, PRECIP CHANCES ALONG AND SOUTH OF I-72 WILL RAMP UP TO LIKELY, WITH CATEGORICAL POPS SOUTH OF I-70 AS THE LOW PASSES JUST SOUTH OF STATE HWY 50. HEAVY PRECIP REMAINS POSSIBLE WED NIGHT INTO THURSDAY MORNING SOUTH OF I-70, AS PRECIPITABLE WATER VALUES CLIMB TO 1.8". WILL MONITOR FOR POSSIBLE FLASH FLOOD WATCH, BUT DRY CONDITIONS RECENTLY MAY HELP PREVENT FLASH FLOODING. ALSO, A DRIER TREND IN THE 12Z MODELS HAS LOWERED CONFIDENCE IN VERY HEAVY RAINFALL IN OUR SOUTHERN COUNTIES. THURSDAY SHOULD SEE DRY CONDITIONS RETURN BY AFTERNOON AS THE LOW PULLS AWAY TO THE EAST AND HIGH PRESSURE GAINS CONTROL OF THE LOCAL WEATHER. RIDGING ALOFT WILL REACH WESTERN IL, WITH HEIGHT RISES HELPING HIGHS REACH THE LOW 80S. LOW PRESSURE TRACKING FROM THE DAKOTAS THURSDAY AFTERNOON TO EASTERN LAKE SUPERIOR SATURDAY MORNING COULD DRAG A WEAKENING COLD FRONT INTO NORTHERN IL LATE FRIDAY INTO FRI EVENING. WE ONLY ACKNOWLEDGED THAT FEATURE WITH SLIGHT CHANCE POPS WEST OF I-55 FOR NOW. THERE ARE INDICATIONS IN THE EXTENDED MODELS THAT AN MCS COULD DEVELOP IN NEBRASKA ON SATURDAY, THEN PROGRESS EASTWARD INTO CENTRAL IL SAT NIGHT-SUNDAY. THE CANADIAN IS THE NORTHERN OUTLIER WITH THE TRACK OF THE SYSTEM, KEEPING IT GENERALLY NORTH OF OUR COUNTIES, WHILE THE GFS/ECMWF BOTH PUSH THE WAVE INTO CENTRAL IL. WILL KEEP CHANCE POPS FOR THE ENTIRE FORECAST AREA SUNDAY INTO SUNDAY NIGHT, WITH DECREASING CHANCES FROM WEST TO EAST ON MONDAY. DRY CONDITIONS ARE EXPECTED FOR TUESDAY AS AN UPPER TROUGH BUILDS INTO THE AREA. HEAT AND HUMIDITY ARE PROJECTED TO INCREASE SATURDAY AND CONTINUE INTO MONDAY, WITH HIGHS IN THE MID 80S AND HEAT INDICES IN THE LOWER 90S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 600 PM CDT TUE AUG 4 2015 VFR CONDITIONS ARE EXPECTED THRU THIS FORECAST PERIOD. FRONTAL BOUNDARY OVER FAR SOUTHERN IL WILL BE THE FOCUS FOR PERIODS OF SHOWERS AND STORMS OVER THE NEXT 12 TO 24 HOURS WITH MOST OF THE ACTIVITY EXPECTED TO REMAIN JUST TO THE SOUTH OF SPI AND DEC THRU ABOUT 13Z WITH THE THREAT SLOWLY SHIFTING NORTHEAST DURING THE MORNING AS AN AREA OF LOW PRESSURE APPROACHES FROM THE WEST. ONCE AGAIN...SURFACE WINDS WILL HAVE VERY LITTLE IF ANY IMPACT ON OPERATIONS THIS FORECAST PERIOD WITH WINDS NEARLY CALM TONIGHT AND TRENDING INTO A LIGHT EASTERLY FLOW ON WED WITH SPEEDS AVERAGING LESS THAN 10 KTS. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...SHIMON LONG TERM...SHIMON AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS LINCOLN IL
308 PM CDT TUE AUG 4 2015 .SHORT TERM...(TONIGHT) ISSUED AT 303 PM CDT TUE AUG 4 2015 A STATIONARY FRONTAL BOUNDARY WILL LINGER ACROSS SOUTHERN IL TONIGHT, WHERE BETTER CHANCES OF SHOWERS AND STORMS SHOULD START OUT THE EVENING. NORTH OF THE BOUNDARY INTO OUR SOUTHERN COUNTIES, WEAK ISENTROPIC LIFT AND MID LEVEL CONVERGENCE WILL WORK TO TRIGGER SHOWERS AND A FEW STORMS TOWARD SPRINGFIELD TO MATTOON TONIGHT. THIS AFTERNOON, SHOWERS/STORMS DEVELOPED WELL NORTH OF WHERE THE HRRR AND RAP MODELS INDICATED, SO THE FACT THAT THEY CONTINUE TO SHOW DRY CONDITIONS OVERNIGHT FOR OUR COUNTIES DOES NOT PRECLUDE THAT SHOWERS REACH AS FAR NORTH AS LINCOLN TO MATTOON AGAIN OVERNIGHT. ONGOING SHOWERS/STORMS LATE THIS AFTERNOON FROM SPRINGFIELD TO SHELBYVILLE ARE EXPECTED TO DISSIPATE AS THEY PROGRESS EASTWARD. THEREFORE WILL START OUT THE EVENING GRIDS WILL MAINLY SLIGHT CHANCE IN OUR SOUTHERN COUNTIES, BUT MAY ADJUST POPS UP AS LATE AFTERNOON CONDITIONS WARRANT. DESPITE THE DRY HIGH RESOLUTION MODELS TONIGHT, THE CONSENSUS OF THE GFS, NAM, ECMWF AND CANADIAN INDICATES ENOUGH FORCING FOR PRECIP REDEVELOPING ACROSS OUR SOUTHERN COUNTIES. THEREFORE, HAVE NOT STRAYED FAR FROM THE CURRENT FORECAST OF CHANCE POPS EXPANDING NORTH TO AREAS SOUTHWEST OF A LINE FROM CANTON TO LINCOLN TO MATTOON. LOW TEMPS TONIGHT WILL VARY BASED ON THE AMOUNT OF CLEARING THAT DEVELOPS UNDER LIGHT ENE FLOW. AFTERNOON DEWPOINTS HAVE POINTED TOWARD LOWS TONIGHT GENERALLY IN THE LOWER 60S NORTH OF I-74, WITH UPPER 60S IN SOUTH OF I-70, WHERE CLOUDS MAY BE MORE PREVALENT LATER TONIGHT. && .LONG TERM...(WEDNESDAY THROUGH TUESDAY) ISSUED AT 303 PM CDT TUE AUG 4 2015 WEDNESDAY COULD START OUT WILL A LULL IN THE SHOWERS AS THE ENERGY FROM THE OVERNIGHT CONVECTION SHIFTS EAST INTO INDIANA. THE NEXT WAVE OF PRECIP LOOKS TO BE TIED TO THE ADVANCEMENT OF A LOW PRESSURE SYSTEM FROM THE CENTRAL PLAINS ACROSS SOUTH CENTRAL IL. THE 12Z MODELS HAVE CONTINUED WITH THE SOUTHWARD TREND OF TRACKING THE LOW ACROSS IL WEDNESDAY NIGHT INTO THURSDAY. HOWEVER, THEY ALSO CONTINUE TO PROJECT OVERRUNNING SHOWERS/STORMS DEVELOPING AHEAD OF THE LOW WED AFTERNOON ACROSS OUR SOUTHERN COUNTIES. WEDNESDAY NIGHT, PRECIP CHANCES ALONG AND SOUTH OF I-72 WILL RAMP UP TO LIKELY, WITH CATEGORICAL POPS SOUTH OF I-70 AS THE LOW PASSES JUST SOUTH OF STATE HWY 50. HEAVY PRECIP REMAINS POSSIBLE WED NIGHT INTO THURSDAY MORNING SOUTH OF I-70, AS PRECIPITABLE WATER VALUES CLIMB TO 1.8". WILL MONITOR FOR POSSIBLE FLASH FLOOD WATCH, BUT DRY CONDITIONS RECENTLY MAY HELP PREVENT FLASH FLOODING. ALSO, A DRIER TREND IN THE 12Z MODELS HAS LOWERED CONFIDENCE IN VERY HEAVY RAINFALL IN OUR SOUTHERN COUNTIES. THURSDAY SHOULD SEE DRY CONDITIONS RETURN BY AFTERNOON AS THE LOW PULLS AWAY TO THE EAST AND HIGH PRESSURE GAINS CONTROL OF THE LOCAL WEATHER. RIDGING ALOFT WILL REACH WESTERN IL, WITH HEIGHT RISES HELPING HIGHS REACH THE LOW 80S. LOW PRESSURE TRACKING FROM THE DAKOTAS THURSDAY AFTERNOON TO EASTERN LAKE SUPERIOR SATURDAY MORNING COULD DRAG A WEAKENING COLD FRONT INTO NORTHERN IL LATE FRIDAY INTO FRI EVENING. WE ONLY ACKNOWLEDGED THAT FEATURE WITH SLIGHT CHANCE POPS WEST OF I-55 FOR NOW. THERE ARE INDICATIONS IN THE EXTENDED MODELS THAT AN MCS COULD DEVELOP IN NEBRASKA ON SATURDAY, THEN PROGRESS EASTWARD INTO CENTRAL IL SAT NIGHT-SUNDAY. THE CANADIAN IS THE NORTHERN OUTLIER WITH THE TRACK OF THE SYSTEM, KEEPING IT GENERALLY NORTH OF OUR COUNTIES, WHILE THE GFS/ECMWF BOTH PUSH THE WAVE INTO CENTRAL IL. WILL KEEP CHANCE POPS FOR THE ENTIRE FORECAST AREA SUNDAY INTO SUNDAY NIGHT, WITH DECREASING CHANCES FROM WEST TO EAST ON MONDAY. DRY CONDITIONS ARE EXPECTED FOR TUESDAY AS AN UPPER TROUGH BUILDS INTO THE AREA. HEAT AND HUMIDITY ARE PROJECTED TO INCREASE SATURDAY AND CONTINUE INTO MONDAY, WITH HIGHS IN THE MID 80S AND HEAT INDICES IN THE LOWER 90S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1240 PM CDT TUE AUG 4 2015 STALLED BOUNDARY TO THE SW AND REGION MAINLY DOMINATED BY CIRRUS BLOW OFF FROM OVERNIGHT AND CURRENT CONVECTION TO THE WEST AND SOUTHWEST...SOME MID LEVEL IN SPI AND DEC CLOSER TO THE BOUNDARY. LIGHT AND VARIABLE WINDS AS THE WEAK BOUNDARY DRIFTS SLIGHTLY. WAVE MOVING INTO THE WEST LIKELY TO IMPACT SPI IN THE SHORT TERM AND HAVE A TEMPO FOR TS. MAY NEED AN UPDATE FOR DEC SHOULD THE STORMS HOLD TOGETHER. HOWEVER, MODELS HAVE BEEN CONSISTENTLY ERODING THE STORMS WITH EASTERN PROGRESSION. MODELS VARYING ENOUGH WITH FUTURE PRECIP TOMORROW MORNING THAT IT IS LEFT OUT OF THE TAF ALTOGETHER. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...SHIMON LONG TERM...SHIMON AVIATION...HJS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
550 PM MDT WED AUG 5 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 238 PM MDT WED AUG 5 2015 FORECAST CONCERNS WILL BE LOW CHANCE OF THUNDERSTORMS IN THE NORTHWEST CORNER THROUGH THE MIDDLE OF THE NIGHT...THE EXTENT OF THE FOG LATER TONIGHT INTO TOMORROW MORNING...AND ANOTHER CHANCE OF THUNDERSTORMS ON THURSDAY. SATELLITE SHOWING MODELS INITIALLY WELL AT MID AND UPPER LEVELS. THE SREF WAS DOING A LITTLE BETTER THAN THE GFS AND RAP ON THE SURFACE WIND AND PRESSURE FIELD. THE GFS AND CANADIAN WERE DOING A LITTLE BETTER THAN THE SREF AND NAM ON THE LOW LEVEL THERMAL FIELD. TONIGHT...A SURFACE BOUNDARY HAS SET UP ALONG THE WESTERN END OF THE AREA WITH SOME CUMULUS DEVELOPMENT. THAT DEVELOPMENT SHOULD CONTINUE WITH LITTLE TO NO CAP. HOWEVER...THERE IS MUCH AT MID TO UPPER LEVELS UNTIL THE MID EVENING INTO THE OVERNIGHT. A SHORTWAVE TROUGH STARTS MOVING THROUGH IN THE LATER HALF OF THE NIGHT AND THERE ALSO LOOKS TO BE SOME WEAK JET LIFT AFFECTING THE NORTHWEST CORNER THROUGH THE MIDDLE OF TONIGHT. INITIALLY THE NAM IS THE MOST AGGRESSIVE IN PRODUCING THUNDERSTORMS LATER THIS AFTERNOON INTO THE OVERNIGHT HOURS. NOW THE RAP AND HRRR ARE SUPPORTING SOME ISOLATED DEVELOPMENT IN THE AREA OF CONVERGENCE THAT IS GOING ON RIGHT NOW. THIS AREA THEN SHIFTS TO THE NORTH AND EAST THROUGH THE NIGHT. LIFT AND WARM AIR ADVECTION ALOFT INCREASE A GREAT DEAL IN THE EASTERN PORTION OF THE AREA DURING THE LAST HALF OF THE NIGHT. MODELS WOULD INDICATE A STRONG CAP ALOFT BUT MORE THAN ONE PIECE OF GUIDANCE IS INDICATING SOME LIGHT QPF. AM A LITTLE CONCERNED ABOUT THIS ACTIVITY. IF THE LIFT BREAKS THE CAP...THE INSTABILITY AND PWS ARE RATHER IMPRESSIVE. WOULD NOT BE SURPRISED TO HAVE SOME STRONG STORMS WITH SOME HEAVY RAINFALL. THURSDAY...THE NAM AND OTHER HIGH RESOLUTION GUIDANCE DEVELOPS PRECIPITATION OVER THE CENTRAL AND EASTERN PORTION OF THE AREA EARLY IN THE DAY. THIS MATCHES WELL WITH THE INSTABILITY AND SHORTWAVE TROUGH MOVING THROUGH SO WILL CONTINUE THE SLIGHT CHANCE POPS THROUGH THE MORNING. WILL BE POTENTIAL FOR STRONG STORMS AND HEAVY RAINFALL. SOME FOG AND ESPECIALLY STRATUS WILL BE AROUND THROUGH THE MORNING. THIS WILL BE IN ADVANCE OF A BOUNDARY MOVING THROUGH. MODELS BRING THIS BOUNDARY THROUGH DURING THE LATE MORNING AND AFTERNOON. MOST OF THE MODEL OUTPUT WOULD INDICATE THAT NOT MUCH COOLING WILL OCCUR WITH THIS SURFACE TROUGH/WEAK FRONT. THIS DOES MAKE SENSE CONSIDERING THE WESTERLY FLOW ALOFT AND STRONG RIDGE TO OUR SOUTH. SO THE HIGH TEMPERATURE FORECAST WILL BE A LITTLE TRICKY DUE TO THE VARIABLE NATURE OF THE CLOUD COVER...SOME PRECIPITATION POSSIBLE...AND THE BOUNDARY TIMING. SO WENT COOLER IN THE EAST WHERE THE CLOUD COVER LASTS LONGER AND THE 850 MB TEMPERATURES ARE THE COOLEST. HOTTER TEMPERATURES WILL BE IN THE SOUTH AND WEST IT DOES APPEAR. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 116 PM MDT WED AUG 5 2015 RIDGE AXIS BUILDS OVER THE HIGH PLAINS THURSDAY NIGHT RESULTING IN DRY CONDITIONS. NEXT SHORTWAVE TROUGH WILL TOP THE RIDGE FRIDAY AFTERNOON AND EVENING BRINGING A GOOD CHANCE FOR THUNDERSTORMS. WHILE SHEAR/INSTABILITY PARAMETERS ARE NOT OVERWHELMING...THEY ARE PROBABLY SUFFICIENT FOR ANOTHER ROUND OF SEVERE WEATHER WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. NAM PRECIPITABLE WATER VALUES INCREASE TO 1-1.5 INCHES BY 00Z/SAT AND STORM MOTIONS WILL BE NORTHEAST AT AROUND 20KTS...NEITHER PARAMETER REALLY SUGGESTING WIDESPREAD HEAVY RAINFALL THOUGH THERE WILL CERTAINLY BE SOME LOCAL DELUGES...ESPECIALLY NEAR RIGHT MOVING SUPERCELLS WHERE STORM MOTIONS WILL BE MUCH SLOWER. THE PATTERN DOESNT CHANGE MUCH ON SATURDAY WITH A BROAD SOUTHWESTERLY FLOW ALOFT AND EMBEDDED WEAK SHORTWAVE TROUGH BRINGING ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME SEVERE WITH SUFFICIENT SHEAR/INSTABILITY FORECAST ONCE AGAIN. WILD CARD WILL BE LOCATION OF SURFACE BOUNDARIES WHICH MAY BE INFLUENCED BY PREVIOUS DAYS CONVECTION AND WILL BE HARD TO PIN DOWN AT THIS TIME...BUT MAY PROVE TO BE PIVOTAL FOR CONVECTIVE INITIATION. SUNDAY THROUGH WEDNESDAY THE RIDGE IS FORECAST TO BUILD SHARPLY NORTHWARD WITH THE RIDGE AXIS BY WEDNESDAY CENTERED OVER THE HIGH PLAINS FROM CANADA TO THE TEXAS PANHANDLE. FOR THIS REASON AM SOMEWHAT SKEPTICAL OF PRECIPITATION CHANCES IN THE GLOBAL MODELS AND THE DERIVED BLENDS USED TO INITIATE THE EXTENDED THE PERIODS. NONETHELESS...SURFACE PROGS SHOW A CONSISTENT MOIST SOUTHEASTERLY FLOW INTO THE REGION WITH RESULTANT INSTABILITY EACH DAY. SO THE ATMOSPHERE WILL BE PRIMED FOR LIFT AND ANY MINOR DISTURBANCE WHICH MAY MAKES ITS WAY THROUGH THE RIDGE MAY BE ENOUGH FOR CONVECTION TO DEVELOP. HOWEVER DEEP LAYER SHEAR WILL BE RATHER LOW UNDER THE RIDGE SO SEVERE THREAT SHOULD BE LIMITED. TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 543 PM MDT WED AUG 5 2015 A FEW THUNDERSTORMS POSSIBLE ACROSS NORTHWEST PORTIONS OF THE AREA BUT DO NOT ANTICIPATE MUCH OF AN IMPACT ON TERMINAL FORECASTS BUT MAY HAVE A STORM OR TWO NEAR MCK VICINITY LATER TONIGHT. FOG POTENTIAL AGAIN A CONCERN AND THINK MOST LIKELY AREA WILL BE EAST OF A TO TRIBUNE LINE WITH HIGHEST CHANCES AT MCK. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...024 AVIATION...JRM
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1030 PM CDT WED AUG 5 2015 .UPDATE... ISSUED AT 1030 PM CDT WED AUG 5 2015 MINOR UPDATE TO ADDRESS MOVEMENT OF WEAKENED MCV/OPEN SHORTWAVE CIRCULATION TO THE NORTH AND THE GRADIENT LIFT ALONG AND SOUTH OF THE IMPRESSED STATIONARY FRONTAL BOUNDARY ALONG THE SOUTHERN BORDER OF THE WFO PAH FORECAST AREA. THE HRRR SUGGESTS THAT THE MEAN LIFT AND ROTATION AROUND THE CIRCULATION IN SOUTHERN ILLINOIS IS A LITTLE FURTHER SOUTH THAN ADVERTISED BY THE 12KM NAM-WRF. HOWEVER...AS THE NEXT WAVE ROTATES INTO SOUTHEAST MISSOURI AFTER MIDNIGHT, ENOUGH FORCING WILL BE IN PLACE TO LIFT AND CONDENSE MOISTURE NORTHEAST ACROSS THE STATIONARY BOUNDARY INTO WEST KENTUCKY...WHILE MAINTAINING LIFT ALONG AND NORTHEAST OF THE MAIN CIRCULATION CENTER IN SOUTHERN ILLINOIS. WITH THAT SCENARIO IN PLACE...WILL LEAVE FLASH FLOOD WATCH IN PLACE FOR THE WFO PAH FORECAST AREA AT THIS TIME. THERE MAY BE AN OPPORTUNITY AFTER MIDNIGHT TO DROP NORTHERN SECTIONS OF SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS BEFORE 7 AM CDT...AS THE EVOLUTION OF THE LAST MINOR IMPULSE OVER SOUTHEAST MISSOURI TAKES PLACE ALONG AND SHORTLY AFTER MIDNIGHT. OTHERWISE...ONLY MINOR ADJUSTMENTS MADE TO REFLECT SHORT TERM PRECIPITATION AND SENSIBLE WEATHER ELEMENTS VARIATIONS. UPDATE ISSUED AT 635 PM CDT WED AUG 5 2015 UPDATED THE AVIATION DISCUSSION FOR THE 00Z TAF ISSUANCE. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 312 PM CDT WED AUG 5 2015 LINE OF CONVECTION MOVING INTO SOUTHEAST MISSOURI WILL PUSH THROUGH MUCH OF SOUTHEAST MISSOURI LATE THIS AFTERNOON AND THEN LIKELY PIVOT TO MORE OF A NORTHWEST TO SOUTHEAST BAND OVER SOUTHERN ILLINOIS AND WEST KENTUCKY THIS EVENING. NOTICING NEW SCATTERED CONVECTION TO THE NORTHEAST AND SOUTHWEST OF KSTL AS THE PRIMARY CIRCULATION TAKES SHAPE OVER CENTRAL MISSOURI. THIS MAY BE THE BEGINNING OF A DEFORMATION ZONE ABOUT THE CIRCULATION. THE DISTURBANCE WILL BE SLOW TO PUSH EAST THROUGH THE REGION TONIGHT...SO FIGURE THERE WILL STILL BE SIGNIFICANT RAINFALL...ESPECIALLY EAST OF THE MISSISSIPPI RIVER. SO WILL KEEP THE FLASH FLOOD WATCH GOING FOR THE ENTIRE ARE AT THIS TIME...BUT IT MAY BE MORE OF AN AREAL FLOOD EVENT...AND NOT SO MUCH OF A FLASH FLOOD EVENT. PLAN ON CANCELING AT LEAST THE WESTERN 4 COUNTIES IN MISSOURI ONCE THE LINE HAS PASSED THERE IN AN HOUR OR TWO. FIGURE THAT THE PRECIPITATION WILL MOSTLY BE DONE BEFORE 18Z THURSDAY IN THE EAST...BUT WILL KEEP A CHANCE IN THE SOUTHEAST THROUGH THE AFTERNOON JUST TO GIVE IT A WIDE BERTH. STILL HAVE A CHANCE OF CONVECTION MAINLY OVER SOUTHEAST MISSOURI LATE THURSDAY NIGHT AND FRIDAY...AS ANOTHER DISTURBANCE PUSHES SOUTHEAST THROUGH THE AREA. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 312 PM CDT WED AUG 5 2015 UNLIKE MOST LATE SUMMER SITUATION...THE NORMALLY DOMINANT SOUTHEAST U.S. RIDGE IS NOTICEABLY ABSENT THIS SUMMER. ALTHOUGH CPC SUGGESTS CURRENT EL NINO REGIME IMPACT IS MINIMAL ACROSS THE U.S. ...WE CONTINUE TO BE LOCKED INTO A MEAN NORTHWEST FLOW PATTERN WITH THE MEAN CENTER OF THE BROAD 500 MB HIGH PRESSURE CENTER WAFFLING BETWEEN TEXAS AND THE FOUR CORNERS AREA OF THE DESERT SOUTHWEST. MODEL INITIALIZATION...FROM A SATELLITE PERSPECTIVE...GIVES CREDENCE TO THE DETERMINISTIC AND ENSEMBLE GFS SOLUTIONS FOR THE MEDIUM RANGE TIME PERIOD. FROM OTHER SENSIBLE WEATHER PERSPECTIVES THE DETERMINISTIC ECMWF HAS A SLIGHT EDGE OVER ITS GFS COUNTERPART. STARTING FROM A BLENDED MEDIUM RANGE MODEL INITIALIZATION...UTILIZED A VARIABLE WEIGHTING OF THE GFS/NAM/GEM/ECMWF...DEPENDING ON THE WEATHER ELEMENT IN QUESTION. THE EXTENDED FORECAST PERIOD STARTS (ON SATURDAY) WITH THE MEAN RIDGE AXIS DOMINATING THE AREA...SUPPRESSING ANY CONVECTION THROUGH AT LEAST EARLY SUNDAY. LOW PRESSURE CENTERS ROTATING NORTHEAST FROM THE NORTHWEST PACIFIC COAST INTERACT WITHE SEMIPERMANENT LOW WOBBLING ALONG ACROSS THE CANADIAN PROVINCES OF MANITOBA AND ONTARIO. AS THESE LOWS ARE PHASED INTO THE MEAN WEST- NORTHWEST BAROCLINIC ZONE BETWEEN THE CANADIAN LOW AND THE SOUTHER U.S. RIDGE SUNDAY NIGHT THROUGH TUESDAY...RAINFALL CHANCES ARE EXPECTED GENERATE A NORTH TO SOUTH GRADIENT OF POPS/WEATHER (HIGHEST NORTH NEAR INTERSTATE 64) DURING THIS TIME PERIOD. CONFIDENCE IS ABOUT 50/50 ON THE RANGE OF POPS/WEATHER...MAINLY DUE THE UNCERTAINTY ON ANY MESOSCALE PERTURBATIONS IN THE SAME FLOW...WHICH CAN ENHANCE/DIMINISH POPS FROM ONE PERIOD TO ANOTHER. THE RIDGE DOES NOT MOVE INTO THE AREA UNTIL WEDNESDAY...WHEN RELATIVELY DRY WEATHER RETURNS FOR THE END OF THE FORECAST PERIOD. MAXIMUM TEMPERATURES SHOULD REMAIN IN THE 80S DURING THE PERIOD...WITH LOWS IN THE UPPER 60S AND LOWER 70S...STILL BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION... ISSUED AT 635 PM CDT WED AUG 5 2015 WITH THE APPROACH AND PASSAGE OF A FRONTAL BOUNDARY AND UPPER LEVEL TROUGH...VFR CONDITIONS WILL BECOME MVFR/IFR...ESPECIALLY IN SHRA/TSRA...BY 05-06Z AND CONTINUE THROUGH THE END OF THE PERIOD. SOUTH TO SOUTHWEST WINDS GENERALLY AOB 6 KNOTS WILL VEER AROUND TO THE NORTHWEST WITH THE FRONTAL PASSAGE. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR ILZ076>078-082- 083-086-087-089>094. FLASH FLOOD WATCH UNTIL 7 AM CDT THURSDAY FOR ILZ075-080-081-084- 085-088. MO...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR MOZ108>112-114. FLASH FLOOD WATCH UNTIL 7 AM CDT THURSDAY FOR MOZ076-086-087-100- 107. IN...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR INZ081-082- 085>088. KY...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR KYZ001>022. && $$ UPDATE...SMITH SHORT TERM...DRS LONG TERM...SMITH AVIATION...JP
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
206 PM CDT TUE AUG 4 2015 .AVIATION... EXPECTING VFR FLIGHT CATEGORIES TO PREVAIL THROUGH THE TERMINAL FORECAST PERIOD ENDING 05/18Z WITH THE SMALL EXCEPTION OF AREAS NEAR AND UNDER ISOLATED THUNDERSTORMS THIS AFTERNOON AND EARLY EVENING THAT ARE ABLE TO DEVELOP...ALSO EARLY WEDNESDAY MORNING AROUND 05/12-05/14Z OVER PARTS OF DEEP EAST TEXAS WHERE SOME CLOUDS AROUND 2 KFT ARE POSSIBLE. SURFACE WINDS WILL BE LIGHT AND VARIABLE TO SOUTH 5-10 KNOTS. /06/ && .PREV DISCUSSION... /ISSUED 1103 AM CDT TUE AUG 4 2015/ DISCUSSION... TEMPS ARE WARMING QUICKLY THIS MORNING BUT INCREASING CLOUD COVER THROUGH THE DAY SHOULD SLOW THE RATE OF WARMING JUST A BIT. HOWEVER...HIGH TEMPS IN THE UPPER 90S TO NEAR 100 DEGREES F STILL LOOK LIKELY. BAND OF LIGHT TO MODERATE RAIN CONTINUES TO MOVE INTO ERN OK AND PORTIONS OF N TX JUST SOUTH OF THE RED RIVER. EASTWARD PROGRESS IS A COUPLE OF HRS FASTER THAN PROGGED BY THE HIGHER RESOLUTION MODELS SO WILL MAINTAIN SLIGHT CHANCE POPS THIS AFTERNOON ACROSS SE OK/SW AR NORTH OF I-30. ONLY A FEW MINOR TWEAKS TO MADE PRIMARILY TO POPS GRIDS BUT THE OVERALL INTEGRITY OF THE FCST WAS LEFT INTACT. UPDATED TEXT PRODUCTS HAVE BEEN SENT. /09/ PREV DISCUSSION... /ISSUED 706 AM CDT TUE AUG 4 2015/ AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE 04/12Z TAF PERIOD. PERIODS OF CIRRUS WILL CONTINUE TO SPREAD SE INTO THE REGION TODAY BUT SHOULD THIN IN TIME...WITH AREAS OF AC LINGERING THROUGH AT LEAST MID-MORNING OVER PORTIONS OF EXTREME NE TX/SW AR/SE OK. CAN/T RULE OUT A WEAK STRATOCU FIELD DEVELOPING AFTER 13Z OVER SE TX...WHICH MAY AFFECT THE LFK TERMINAL BRIEFLY. OTHERWISE...SHOULD SEE A SCT CU FIELD DEVELOP AREAWIDE BY MIDDAY...WITH ISOLATED CONVECTION POSSIBLE THIS AFTERNOON OVER SE OK/SW AR AND EVEN NCNTRL LA...NEAR A WEAK SHORTWAVE ROUNDING THE ERN PERIPHERY OF THE UPPER RIDGE CENTERED OVER W TX AND THE DESERT SW. ANY ISOLATED CONVECTION THAT DEVELOPS SHOULD DIMINISH BY EARLY EVENING...BUT SHOULD SEE MORE IN THE WAY OF CIRRUS/AC SPREAD ESE INTO THE REGION THIS EVENING. ANY STRATOCU SHOULD WAIT UNTIL AFTER 12Z WEDNESDAY BEFORE AFFECTING PORTIONS OF E TX/NCNTRL LA. S WINDS 4-7KTS TODAY WILL BECOME LIGHT S/LT AND VRB AFTER 00Z. /15/ PREV DISCUSSION... /ISSUED 444 AM CDT TUE AUG 4 2015/ DISCUSSION... A RANGE OF 70S THIS MORNING WITH A DECENT DEW POINT SPREAD STILL IN PLACE AT THIS HOUR. DEW POINTS WILL SPIKE A BIT AROUND MID MORNING...BUT SHOULD MIX OUT ENOUGH TO KEEP THE HEAT INDEX IN THE LOW END OF THE TRIPLE DIGIT...FEELS LIKE TEMPERATURES...NEARLY ALL OF TODAY. HOWEVER...A BIT OF AN INCREASE CAN BE EXPECTED BY TOMORROW WITH AREA WIDE LOW TO MID ONE HUNDRED DEGREE...FEELS LIKE NUMBERS...INTO AND BEYOND MIDWEEK. FOR NOW ANOTHER DAY BELOW CRITERIA FOR THE ADVISORY. OTHERWISE...A FEW CLOUDS ARE DRAPED OVER THE NORTH WITH A SHORT WAVE PULSE PUSHING OFF THE FRONT RANGE INTO THE PLAINS OVER THE TX/OK PANHANDLE AND MUCH OF KN WITH SCATTERED TO NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS. WE COULD SEE A CHANCE FOR CONVECTION LATER TODAY OVER THE NORTH AS THIS ENERGY WORKS EASTWARD OVER AR. MOST MODELS ARE DRY...BUT THE OVERDONE NAM WAS ACTUALLY A STARTING POINT. THE HRRR FLARES IN A BIT OF DEVELOPMENT EARLY TO MID AFTERNOON OVER A GOOD BIT OF REAL ESTATE. SPC HAS ALL BUT EAST TX IN A GENERAL THREAT AND WPC DOES HAVE A BIT OF QPF NORTH. THERE IS A LITTLE CONFIDENCE IN THE SLIGHT POPS SOUTH...BUT HAVE LEFT IN FORECAST FOR TODAY OVER OUR SOUTHERN TIER OF CO/PA. IN THE WAKE OF THIS SHORT WAVE LOOK FOR THE UPPER RIDGE TO LIFT BACK FROM THE SOUTH OVER US AGAIN BY THE WEEKEND WITH CLIMBING AFTERNOON NUMBERS LIKELY. THE GOOD NEWS IS THAT THE MODELS ARE A LITTLE DRIER AND THIS SHOULD KEEP JUST AN ADVISORY CRITERIA GOING AS THE SCHOOL YEAR BEGINS EARLY NEXT WEEK. RAIN WILL CONTINUE TO BE VERY HARD TO COME BY WITH HIGH BASED CU NOT VERY GENEROUS. LAST NIGHTS SOUNDING LEFT US WITH MOISTURE IN THE LOWEST LEVEL AROUND 7.3KFT. THE CIRRUS AND SOME MID DECK WILL HELP TO KEEP SOME MIDDLE 90S ALONG THE I-30 CORRIDOR OF MAINLY AR. EXPECT THE SLIGHT CHANCE FOR RAIN TO LINGER UNDER LOWER HEIGHTS ALOFT FOR A COUPLE OR FEW DAYS AND THEN DISAPPEAR AGAIN AS THE RIDGE EXPANDS BACK NORTHWARD. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 100 78 100 79 / 10 10 20 20 MLU 99 77 98 76 / 10 10 20 20 DEQ 96 74 98 76 / 20 20 20 20 TXK 98 78 100 79 / 10 20 20 20 ELD 98 76 97 76 / 10 20 20 20 TYR 99 78 100 78 / 10 10 10 10 GGG 100 77 100 78 / 10 10 20 20 LFK 97 76 99 76 / 20 10 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 06
AREA FORECAST DISCUSSION...UPDATED
NWS SHREVEPORT LA
1103 AM CDT TUE AUG 4 2015 .DISCUSSION... TEMPS ARE WARMING QUICKLY THIS MORNING BUT INCREASING CLOUD COVER THROUGH THE DAY SHOULD SLOW THE RATE OF WARMING JUST A BIT. HOWEVER...HIGH TEMPS IN THE UPPER 90S TO NEAR 100 DEGREES F STILL LOOK LIKELY. BAND OF LIGHT TO MODERATE RAIN CONTINUES TO MOVE INTO ERN OK AND PORTIONS OF N TX JUST SOUTH OF THE RED RIVER. EASTWARD PROGRESS IS A COUPLE OF HRS FASTER THAN PROGGED BY THE HIGHER RESOLUTION MODELS SO WILL MAINTAIN SLIGHT CHANCE POPS THIS AFTERNOON ACROSS SE OK/SW AR NORTH OF I-30. ONLY A FEW MINOR TWEAKS TO MADE PRIMARILY TO POPS GRIDS BUT THE OVERALL INTEGRITY OF THE FCST WAS LEFT INTACT. UPDATED TEXT PRODUCTS HAVE BEEN SENT. /09/ && .PREV DISCUSSION... /ISSUED 706 AM CDT TUE AUG 4 2015/ AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE 04/12Z TAF PERIOD. PERIODS OF CIRRUS WILL CONTINUE TO SPREAD SE INTO THE REGION TODAY BUT SHOULD THIN IN TIME...WITH AREAS OF AC LINGERING THROUGH AT LEAST MID-MORNING OVER PORTIONS OF EXTREME NE TX/SW AR/SE OK. CAN/T RULE OUT A WEAK STRATOCU FIELD DEVELOPING AFTER 13Z OVER SE TX...WHICH MAY AFFECT THE LFK TERMINAL BRIEFLY. OTHERWISE...SHOULD SEE A SCT CU FIELD DEVELOP AREAWIDE BY MIDDAY...WITH ISOLATED CONVECTION POSSIBLE THIS AFTERNOON OVER SE OK/SW AR AND EVEN NCNTRL LA...NEAR A WEAK SHORTWAVE ROUNDING THE ERN PERIPHERY OF THE UPPER RIDGE CENTERED OVER W TX AND THE DESERT SW. ANY ISOLATED CONVECTION THAT DEVELOPS SHOULD DIMINISH BY EARLY EVENING...BUT SHOULD SEE MORE IN THE WAY OF CIRRUS/AC SPREAD ESE INTO THE REGION THIS EVENING. ANY STRATOCU SHOULD WAIT UNTIL AFTER 12Z WEDNESDAY BEFORE AFFECTING PORTIONS OF E TX/NCNTRL LA. S WINDS 4-7KTS TODAY WILL BECOME LIGHT S/LT AND VRB AFTER 00Z. /15/ PREV DISCUSSION... /ISSUED 444 AM CDT TUE AUG 4 2015/ DISCUSSION... A RANGE OF 70S THIS MORNING WITH A DECENT DEW POINT SPREAD STILL IN PLACE AT THIS HOUR. DEW POINTS WILL SPIKE A BIT AROUND MID MORNING...BUT SHOULD MIX OUT ENOUGH TO KEEP THE HEAT INDEX IN THE LOW END OF THE TRIPLE DIGIT...FEELS LIKE TEMPERATURES...NEARLY ALL OF TODAY. HOWEVER...A BIT OF AN INCREASE CAN BE EXPECTED BY TOMORROW WITH AREA WIDE LOW TO MID ONE HUNDRED DEGREE...FEELS LIKE NUMBERS...INTO AND BEYOND MIDWEEK. FOR NOW ANOTHER DAY BELOW CRITERIA FOR THE ADVISORY. OTHERWISE...A FEW CLOUDS ARE DRAPED OVER THE NORTH WITH A SHORT WAVE PULSE PUSHING OFF THE FRONT RANGE INTO THE PLAINS OVER THE TX/OK PANHANDLE AND MUCH OF KN WITH SCATTERED TO NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS. WE COULD SEE A CHANCE FOR CONVECTION LATER TODAY OVER THE NORTH AS THIS ENERGY WORKS EASTWARD OVER AR. MOST MODELS ARE DRY...BUT THE OVERDONE NAM WAS ACTUALLY A STARTING POINT. THE HRRR FLARES IN A BIT OF DEVELOPMENT EARLY TO MID AFTERNOON OVER A GOOD BIT OF REAL ESTATE. SPC HAS ALL BUT EAST TX IN A GENERAL THREAT AND WPC DOES HAVE A BIT OF QPF NORTH. THERE IS A LITTLE CONFIDENCE IN THE SLIGHT POPS SOUTH...BUT HAVE LEFT IN FORECAST FOR TODAY OVER OUR SOUTHERN TIER OF CO/PA. IN THE WAKE OF THIS SHORT WAVE LOOK FOR THE UPPER RIDGE TO LIFT BACK FROM THE SOUTH OVER US AGAIN BY THE WEEKEND WITH CLIMBING AFTERNOON NUMBERS LIKELY. THE GOOD NEWS IS THAT THE MODELS ARE A LITTLE DRIER AND THIS SHOULD KEEP JUST AN ADVISORY CRITERIA GOING AS THE SCHOOL YEAR BEGINS EARLY NEXT WEEK. RAIN WILL CONTINUE TO BE VERY HARD TO COME BY WITH HIGH BASED CU NOT VERY GENEROUS. LAST NIGHTS SOUNDING LEFT US WITH MOISTURE IN THE LOWEST LEVEL AROUND 7.3KFT. THE CIRRUS AND SOME MID DECK WILL HELP TO KEEP SOME MIDDLE 90S ALONG THE I-30 CORRIDOR OF MAINLY AR. EXPECT THE SLIGHT CHANCE FOR RAIN TO LINGER UNDER LOWER HEIGHTS ALOFT FOR A COUPLE OR FEW DAYS AND THEN DISAPPEAR AGAIN AS THE RIDGE EXPANDS BACK NORTHWARD. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 100 78 100 79 / 10 10 20 20 MLU 99 77 98 76 / 10 10 20 20 DEQ 96 74 98 76 / 20 20 20 20 TXK 98 78 100 79 / 10 20 20 20 ELD 98 76 97 76 / 10 20 20 20 TYR 99 78 100 78 / 10 10 10 10 GGG 100 77 100 78 / 10 10 20 20 LFK 97 76 99 76 / 20 10 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 09
AREA FORECAST DISCUSSION...UPDATED
NWS SHREVEPORT LA
706 AM CDT TUE AUG 4 2015 .AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE 04/12Z TAF PERIOD. PERIODS OF CIRRUS WILL CONTINUE TO SPREAD SE INTO THE REGION TODAY BUT SHOULD THIN IN TIME...WITH AREAS OF AC LINGERING THROUGH AT LEAST MIDMORNING OVER PORTIONS OF EXTREME NE TX/SW AR/SE OK. CAN/T RULE OUT A WEAK STRATOCU FIELD DEVELOPING AFTER 13Z OVER SE TX...WHICH MAY AFFECT THE LFK TERMINAL BRIEFLY. OTHERWISE...SHOULD SEE A SCT CU FIELD DEVELOP AREAWIDE BY MIDDAY...WITH ISOLATED CONVECTION POSSIBLE THIS AFTERNOON OVER SE OK/SW AR AND EVEN NCNTRL LA...NEAR A WEAK SHORTWAVE ROUNDING THE ERN PERIPHERY OF THE UPPER RIDGE CENTERED OVER W TX AND THE DESERT SW. ANY ISOLATED CONVECTION THAT DEVELOPS SHOULD DIMINISH BY EARLY EVENING...BUT SHOULD SEE MORE IN THE WAY OF CIRRUS/AC SPREAD ESE INTO THE REGION THIS EVENING. ANY STRATOCU SHOULD WAIT UNTIL AFTER 12Z WEDNESDAY BEFORE AFFECTING PORTIONS OF E TX/NCNTRL LA. S WINDS 4-7KTS TODAY WILL BECOME LIGHT S/LT AND VRB AFTER 00Z. /15/ && .PREV DISCUSSION... /ISSUED 444 AM CDT TUE AUG 4 2015/ DISCUSSION... A RANGE OF 70S THIS MORNING WITH A DECENT DEW POINT SPREAD STILL IN PLACE AT THIS HOUR. DEW POINTS WILL SPIKE A BIT AROUND MID MORNING...BUT SHOULD MIX OUT ENOUGH TO KEEP THE HEAT INDEX IN THE LOW END OF THE TRIPLE DIGIT...FEELS LIKE TEMPERATURES...NEARLY ALL OF TODAY. HOWEVER...A BIT OF AN INCREASE CAN BE EXPECTED BY TOMORROW WITH AREA WIDE LOW TO MID ONE HUNDRED DEGREE...FEELS LIKE NUMBERS...INTO AND BEYOND MIDWEEK. FOR NOW ANOTHER DAY BELOW CRITERIA FOR THE ADVISORY. OTHERWISE...A FEW CLOUDS ARE DRAPED OVER THE NORTH WITH A SHORT WAVE PULSE PUSHING OFF THE FRONT RANGE INTO THE PLAINS OVER THE TX/OK PANHANDLE AND MUCH OF KN WITH SCATTERED TO NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS. WE COULD SEE A CHANCE FOR CONVECTION LATER TODAY OVER THE NORTH AS THIS ENERGY WORKS EASTWARD OVER AR. MOST MODELS ARE DRY...BUT THE OVERDONE NAM WAS ACTUALLY A STARTING POINT. THE HRRR FLARES IN A BIT OF DEVELOPMENT EARLY TO MID AFTERNOON OVER A GOOD BIT OF REAL ESTATE. SPC HAS ALL BUT EAST TX IN A GENERAL THREAT AND WPC DOES HAVE A BIT OF QPF NORTH. THERE IS A LITTLE CONFIDENCE IN THE SLIGHT POPS SOUTH...BUT HAVE LEFT IN FORECAST FOR TODAY OVER OUR SOUTHERN TIER OF CO/PA. IN THE WAKE OF THIS SHORT WAVE LOOK FOR THE UPPER RIDGE TO LIFT BACK FROM THE SOUTH OVER US AGAIN BY THE WEEKEND WITH CLIMBING AFTERNOON NUMBERS LIKELY. THE GOOD NEWS IS THAT THE MODELS ARE A LITTLE DRIER AND THIS SHOULD KEEP JUST AN ADVISORY CRITERIA GOING AS THE SCHOOL YEAR BEGINS EARLY NEXT WEEK. RAIN WILL CONTINUE TO BE VERY HARD TO COME BY WITH HIGH BASED CU NOT VERY GENEROUS. LAST NIGHTS SOUNDING LEFT US WITH MOISTURE IN THE LOWEST LEVEL AROUND 7.3KFT. THE CIRRUS AND SOME MID DECK WILL HELP TO KEEP SOME MIDDLE 90S ALONG THE I-30 CORRIDOR OF MAINLY AR. EXPECT THE SLIGHT CHANCE FOR RAIN TO LINGER UNDER LOWER HEIGHTS ALOFT FOR A COUPLE OR FEW DAYS AND THEN DISAPPEAR AGAIN AS THE RIDGE EXPANDS BACK NORTHWARD. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 100 78 100 79 / 10 10 20 20 MLU 99 77 98 76 / 10 10 20 20 DEQ 96 74 98 76 / 20 20 20 20 TXK 98 78 100 79 / 10 20 20 20 ELD 98 76 97 76 / 10 20 20 20 TYR 99 78 100 78 / 10 10 10 10 GGG 100 77 100 78 / 10 10 20 20 LFK 97 76 99 76 / 20 10 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 15
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
444 AM CDT TUE AUG 4 2015 .DISCUSSION... A RANGE OF 70S THIS MORNING WITH A DECENT DEW POINT SPREAD STILL IN PLACE AT THIS HOUR. DEW POINTS WILL SPIKE A BIT AROUND MID MORNING...BUT SHOULD MIX OUT ENOUGH TO KEEP THE HEAT INDEX IN THE LOW END OF THE TRIPLE DIGIT...FEELS LIKE TEMPERATURES...NEARLY ALL OF TODAY. HOWEVER...A BIT OF AN INCREASE CAN BE EXPECTED BY TOMORROW WITH AREA WIDE LOW TO MID ONE HUNDRED DEGREE...FEELS LIKE NUMBERS...INTO AND BEYOND MIDWEEK. FOR NOW ANOTHER DAY BELOW CRITERIA FOR THE ADVISORY. OTHERWISE...A FEW CLOUDS ARE DRAPED OVER THE NORTH WITH A SHORT WAVE PULSE PUSHING OFF THE FRONT RANGE INTO THE PLAINS OVER THE TX/OK PANHANDLE AND MUCH OF KN WITH SCATTERED TO NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS. WE COULD SEE A CHANCE FOR CONVECTION LATER TODAY OVER THE NORTH AS THIS ENERGY WORKS EASTWARD OVER AR. MOST MODELS ARE DRY...BUT THE OVERDONE NAM WAS ACTUALLY A STARTING POINT. THE HRRR FLARES IN A BIT OF DEVELOPMENT EARLY TO MID AFTERNOON OVER A GOOD BIT OF REAL ESTATE. SPC HAS ALL BUT EAST TX IN A GENERAL THREAT AND WPC DOES HAVE A BIT OF QPF NORTH. THERE IS A LITTLE CONFIDENCE IN THE SLIGHT POPS SOUTH...BUT HAVE LEFT IN FORECAST FOR TODAY OVER OUR SOUTHERN TIER OF CO/PA. IN THE WAKE OF THIS SHORT WAVE LOOK FOR THE UPPER RIDGE TO LIFT BACK FROM THE SOUTH OVER US AGAIN BY THE WEEKEND WITH CLIMBING AFTERNOON NUMBERS LIKELY. THE GOOD NEWS IS THAT THE MODELS ARE A LITTLE DRIER AND THIS SHOULD KEEP JUST AN ADVISORY CRITERIA GOING AS THE SCHOOL YEAR BEGINS EARLY NEXT WEEK. RAIN WILL CONTINUE TO BE VERY HARD TO COME BY WITH HIGH BASED CU NOT VERY GENEROUS. LAST NIGHTS SOUNDING LEFT US WITH MOISTURE IN THE LOWEST LEVEL AROUND 7.3KFT. THE CIRRUS AND SOME MID DECK WILL HELP TO KEEP SOME MIDDLE 90S ALONG THE I-30 CORRIDOR OF MAINLY AR. EXPECT THE SLIGHT CHANCE FOR RAIN TO LINGER UNDER LOWER HEIGHTS ALOFT FOR A COUPLE OR FEW DAYS AND THEN DISAPPEAR AGAIN AS THE RIDGE EXPANDS BACK NORTHWARD. && .PRELIMINARY POINT TEMPS/POPS... SHV 100 78 100 79 / 10 10 20 20 MLU 99 77 98 76 / 10 10 20 20 DEQ 96 74 98 76 / 20 20 20 20 TXK 98 78 100 79 / 10 20 20 20 ELD 98 76 97 76 / 10 20 20 20 TYR 99 78 100 78 / 10 10 10 10 GGG 100 77 100 78 / 10 10 20 20 LFK 97 76 99 76 / 20 10 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 24/99
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1128 PM CDT MON AUG 3 2015 .DISCUSSION... FOR THE 04/06Z TAF ISSUANCE. && .AVIATION... CLEAR SKIES AND LIGHT WINDS ARE EXPECTED FOR THE REMAINDER OF THE OVERNIGHT...WITH VFR CONDITIONS. ON TUESDAY...BETTER MOISTURE IS EXPECTED ACROSS THE FORECAST AREA. THIS MAY ALLOW FOR SOME MORE CU DEVELOPMENT...ALONG WITH A FEW MORE SHOWERS OR STORMS AS THE SEA BREEZE DEVELOPS IN THE AFTERNOON. FOR NOW...THE LOCATION THAT IS PROGGED TO HAVE A LITTLE BETTER SEA BREEZE CONVERGENCE AND THE BEST CHANCE OF SEEING CONVECTION IS LOWER ACADIANA. THEREFORE...WILL PLACE VCTS AFTER 04/18Z FOR KARA AND AFTER 04/19Z FOR KLFT. RUA && .PREV DISCUSSION... /ISSUED 953 PM CDT MON AUG 3 2015/ DISCUSSION... SEA BREEZE BOUNDARY LIFTED NORTH ABOUT MIDWAY ACRS THE CWA BEFORE DISSIPATING EARLIER THIS EVENING. THE BOUNDARY DIDN`T BRING MORE THAN AN ISLTD SHOWER OR TWO SOUTH OF I-10 BUT WAS FAIRLY EVIDENT ON THE SFC DEWPOINT ANALYSIS...SEPARATING LOWER/MIDDLE 70S SOUTH OF THE BOUNDARY FROM LOWER TO MIDDLE 60S NORTH. HERE AT KLCH THE DEWPOINT CLIMBED FROM 62 DEGREES TO 72 DEGREES BETWEEN 23-00Z. THE END RESULT IS A RETURN OF WARM AND MUGGY CONDITIONS...AND THIS WILL BE THE RULE THROUGH THE REMAINDER OF THE WEEK AS SLY FLOW PREVAILS WITH SFC HIGH PRES TO THE EAST. OVERALL...FEW CHANGES TO THE FCST THIS EVENING. FINE TUNED POPS/WX SLIGHTLY...INCORPORATING A BLEND OF RECENT HRRR RUNS AND ARW GUIDANCE...TO REDUCE POPS OVER THE COASTAL WATERS ZONES BEFORE MIDNIGHT FOLLOWED BY SLT CHC AFTER. SINCE ADJUSTMENTS ONLY AFFECT THE COASTAL WATERS ZONES...WILL NOT UPDATE ZFP AS INLAND FCST REMAINS ON TRACK. 24 PREV DISCUSSION... /ISSUED 443 PM CDT MON AUG 3 2015/ DISCUSSION...SATELLITE IMAGERY DEPICTING SCATTERED CU ABOUT THE INLAND AREA. RADAR SHOWING SCATTERED SHOWER AND THUNDERSTORM ACTIVITY WELL OFFSHORE. SURFACE ANALYSIS SUGGESTING OLD DEWPOINT BOUNDARY NOW EDGING INLAND. ACCORDINGLY...A STRONG MOISTURE GRADIENT IN PLACE OVER THE FORECAST AREA WITH DEWPOINTS RANGING FROM THE MID 70S OVER ACADIANA...INTO THE UPPER 50S TO LOW 60S INTO CENTRAL LOUISIANA AND INTERIOR SOUTHEAST TEXAS. LATEST HRRR INDICATING BOUNDARY WILL PUNCH THROUGH THE REGION DURING THE EVENING HOURS. HENCE...HOT AND HUMID WORDING WILL BE RETURNING TO THE VOCABULARY FOR DAYTIME HIGHS...WARM AND MUGGY FOR THE OVERNIGHT. OVERALL... MOISTURE PROFILES MAINTAIN CONSIDERABLE DRY MID AND UPPER LEVELS THROUGH THE WEEK. THIS AS A NORTHERLY FLOW CONTINUES IN THIS REGION BETWEEN AMPLIFYING WEST CONUS RIDGE...AND PERSISTENT EAST CONUS TROF. THUS MAINTAINING NO MORE THAN LOW END POPS AREA-WIDE. MARINE...A WEAK ONSHORE FLOW AND LOW SEAS CAN BE EXPECTED THROUGH THE WEEK AS HIGH PRESSURE BECOMES REESTABLISHED OVER THE NORTHWEST GULF. 23 && .PRELIMINARY POINT TEMPS/POPS... AEX 73 96 75 95 / 10 20 10 20 LCH 76 94 78 94 / 10 20 10 20 LFT 76 94 77 94 / 10 30 10 30 BPT 75 95 77 94 / 10 20 10 20 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && $$ AVIATION...07
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
919 PM EDT WED AUG 5 2015 .SYNOPSIS... A COLD FRONT LINGERS ACROSS NORTH CAROLINA OVERNIGHT AS HIGH PRESSURE MOVES EAST FROM THE GREAT LAKES. THE FRONT LIFTS BACK NORTH AS A WARM FRONT LATE TONIGHT THROUGH THURSDAY WITH LOW PRESSURE MOVING EAST ALONG IT THURSDAY NIGHT AND FRIDAY. HIGH PRESSURE SLOWLY RETURNS OVER THE WEEKEND. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... QUIET WX THIS EVE ACRS FA W/ WK SFC HI PRES INVOF THE RGN. WATCHING AREA OF CONVECTION SPREADING SLOLY ENE THROUGH SW VA/NW NC. CURRENT FCST APRS IN GOOD SHAPE ATTM...W/ POPS INCRS TO SLGT CHC-CHC ACRS MNLY HALF OF THE FA OVRNGT. ADDED ISOLD TSTMS UNTIL ABT 08-09Z. 23Z/05 RUC GENLY WEAKENS AREA OF CONVECTION AS IT SPREAD TWD/INTO THE FA. HOLDING ONTO SLGT CHC-CHC POPS LT. OTRW...PARTLY CLOUDY N...INCRSG CLDNS S...W/ LO TEMPS FM THE U60S/ARND 70F N TO THE M/U70S FAR SE. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... THE WARM FRONT LIFTS N INTO THE AKQ CWA THURSDAY. THE LOW-LEVEL THETA-E GRADIENT ACTUALLY SHARPENS AS HIGH PRESSURE REMAINS N OF THE REGION. MODELS HAVE COME INTO BETTER AGREEMENT AMONGST THE 12Z SOLUTIONS...ALTHOUGH SOME UNCERTAINTY REMAINS DUE TO THE CONVECTIVE NATURE OF THE ONSET OF THE EVENT. LIKELY POPS HAVE BEEN MAINTAINED ACROSS WRN/CENTRAL PORTIONS...AND LIKELIES HAVE BEEN ADDED TO NE NC/SE VA...AS MODELS SUGGEST AFTERNOON CONVECTION ACROSS THE COASTAL PLAIN OF ERN NC AND SE VA. OVERALL THE PRIMARY THREAT WILL BE LOCALLY HEAVY RAINFALL. HOWEVER...THERE DOES APPEAR TO BE A CORRIDOR FROM NE NC INTO SE VA WHERE A BELT OF STRONGER (30-35KT) 0-6KM BULK SHEAR INTERACTS WITH STRONGER INSTABILITY...WHICH COULD PRODUCE A LOCALIZED SEVERE THREAT. FORECAST HIGHS RANGE FROM THE UPPER 70S NE...TO AROUND 90 SE. LIKELY POPS ARE FORECAST FOR ALL AREAS THURSDAY NIGHT AS LOW PRESSURE DEEPENS ALONG THE SLOWLY ADVANCING WARM FRONT. THE COMBINATION OF A SLOW MOVING SYSTEM...AND ANOMALOUSLY HIGH PW VALUES WILL SUPPORT QPF AMOUNTS OF 1-2 INCHES WITH LOCALLY MUCH HIGHER AMOUNTS POSSIBLE FROM THURSDAY AFTERNOON THROUGH EARLY FRIDAY. HEAVY RAIN POTENTIAL WILL BE MAINTAINED IN THE HWO. LOWS SHOULD BE IN THE UPPER 60S TO LOWS 70S. MODELS BEGIN TO DIVERGE FRIDAY WITH RESPECT TO HOW FAST THE SYSTEM PULLS OFFSHORE. THE 12Z GFS SEEMS TO BE A REASONABLE COMPROMISE OF THE QUICKER NAM AND SLOWER ECMWF. LIKELY POPS WILL BE MAINTAINED GIVEN THE AMPLIFICATION OF THE OVERALL PATTERN...ALTHOUGH PCPN COULD TAPER OFF FROM THE W DURING THE AFTERNOON. CONTINUED LOW-LEVEL NE FLOW SHOULD RESULT IN PERSISTENT CLOUD COVER AND BELOW NORMAL HIGH TEMPERATURES. THIS WILL KEEP HIGHS BELOW NORMAL RANGING FROM THE MID 70S NW...TO THE LOW 80S SE. HIGH PRESSURE GRADUALLY BUILD IN FROM THE N FRIDAY NIGHT INTO SATURDAY. BY SATURDAY...THE SKY SHOULD BECOME PARTLY SUNNY W...AND REMAIN MOSTLY CLOUDY ALONG THE COAST WITH A 20-30% POP. LOWS RANGE FROM THE MID 60S TO LOW 70S FRIDAY NIGHT...WITH HIGHS IN THE LOW 80S SATURDAY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... STRENGTHENING SURFACE LOW PRESSURE MOVES OFF THE MID-ATLANTIC COAST SAT NIGHT...PULLING CLOUDS AND PRECIP OUT TO SEA WITH IT. WEAK HIGH PRESSURE MOVES OVER THE AREA SUN AND MON WITH INCREASING MID LEVEL DYNAMIC FORCING ON MONDAY. INCREASING POPS MONDAY THROUGH WED AS WEAK SURFACE TROUGH ON TUE AHEAD OF AN APPROACHING COLD FRONT HELPING TO INITIATE SCATTERED PRECIPITATION. FAIRLY GOOD MODEL AGREEMENT WITH THE TIMING OF THE UPPER WAVE AND SURFACE FRONT MOVING THROUGH THE AREA ON WEDNESDAY WITH WIDESPREAD PRECIP POSSIBLE. MODELS DEPICT AN OMEGA LIKE BLOCK FOR THE END OF THE EXTENDED FORECAST...KEEPING UPPER LEVEL LOW OVER THE AREA WHICH WILL HELP MAINTAIN CLOUDS AND ISOLATED SHOWERS IN THE FORECAST. TEMPS UPPER 80S MON AND TUES AHEAD OF THE FRONT WED MODERATING INTO THE LOW TO MID 80S ON THURS. && .AVIATION /01Z THURSDAY THROUGH MONDAY/... AT 00Z...VFR CONDS PREVAIL ACROSS THE REGION WITH NO CONVECTION AFFECTIING THE CWA. A WEAK STATIONARY FRONT CONTS TO LIE JUST SOUTH OF THE VA BORDER WITH A WEAK WAVE MOVG ALONG THE FRONT OVER N CENTRAL NC. ANOTHER WAVE ON THE BNDRY IS MOVG THRU THE TN VALLEY AND WILL BRING SHOWERS/TSTMS TO THE AREA BY THU MORNING/AFTN. INCREASING MID-UPR LEVEL CLOUDS ARE EXPECTED TO STREAM INTO THE AREA DURING THE OVERNIGHT AND EARLY MORNING. LWR CIGS AND VSBYS LIKELY AT ALL TAF SITES BY LATE THU INTO FRI. HI PRES WILL BUILD INTO AND OVR THE AREA FOR SAT AFTN THRU SUN. && .MARINE... AN AREA OF LOW PRESSURE PROGGED TO DEVELOP ALONG A STALLED FRONTAL BOUNDARY THURSDAY AS HIGH PRESSURE BUILDS INTO NEW ENGLAND. THE RESULT WILL BE ONSHORE FLOW THURS AOB 15 KT. GRADIENT STRENGTHENS THURS NIGHT AS THE LOW DEEPENS IN THE VICINITY OF EASTERN NC. MODELS COMING INTO BETTER AGREEMENT WITH RESPECT TO THE LOW PLACEMENT AND RESULTANT FRONTAL LOCATION. CONFIDENCE CONTINUES TO INCREASE FOR STRONG SCA CONDITIONS FRIDAY INTO SATURDAY DUE TO STRENGTH OF THE PRESSURE GRADIENT AND NE FLOW. SEAS RESPOND...BUILDING TO 4 T0 6+ FT FRI NIGHT THOUGH SAT. LOW PROGGED TO LIFT AWAY FROM THE COAST SAT NIGHT INTO SUN...ALLOWING THE GRADIENT TO RELAX AND WINDS/SEAS TO SLOWLY DIMINISH/SUBSIDE. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...AJZ/ALB/LKB NEAR TERM...AJZ/ALB SHORT TERM...AJZ/LKB LONG TERM...DAP AVIATION...TMG/JEF MARINE...MAS/DAP
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
121 AM EDT TUE AUG 4 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 346 PM EDT MON AUG 3 2015 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW CYC NW FLOW ARND CLOSED LO OVER FAR NRN ONTARIO DOMINATING THE UPR LKS. UPSTREAM 12Z RAOBS AT INL/YPL SHOW SOME FAIRLY DEEP MSTR...WITH H85-7 DEWPT DEPRESSIONS NO MORE THAN A FEW DEGREES C. WITH LARGER SCALE CYC FLOW AND H85 CAA /12Z H85 TEMPS WERE 11C AT GRB/APX BUT ONLY 3C AT YPL/...BKN LO CLDS ARE PRESENT OVER THE CWA. THERE HAVE BEEN A FEW SHOWERS MAINLY OVER THE INTERIOR AS WELL WITH SOME DIURNAL HEATING AND IN ASSOCIATION WITH SHRTWV NOTED ON WV IMAGERY PASSING OVER NE LK SUP/ACCOMPANYING DPVA AND DEEP LYR QVECTOR CNVGC...BUT INTENSITY/ COVERAGE OF THESE HAS BEEN LIMITED BY SOME CAPPING AOA H7 AS SHOWN ON THE 12Z YPL RAOB AND RUC ANALYSIS SNDGS FOR SITES IN THE CWA. THE CAA AND CLD COVER HAVE KEPT TEMPS BLO NORMAL. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON CLD TRENDS AND POPS. TNGT...EXPECT ANY ONGOING SHOWERS EARLY TO TEND TO DIMINISH IN THE EVNG WITH NOCTURNAL COOLING/ARRIVAL OF DNVA/LARGER SCALE SUBSIDENCE IN THE WAKE OF PASSING SHRTWV TO THE NE. SOME OF THE MODELS INDICATE ANOTHER SHRTWV NOW SLIDING SEWD THRU MANITOBA WL ARRIVE DURING THE NGT AND RESULT IN MORE ISOLD SHOWERS. LINGERING CYC FLOW AND CONTINUED MOIST...CYC NW H85 FLOW WL MAINTAIN A GOOD DEAL OF CLD COVER THAT WL LIMIT THE DIURNAL TEMP FALL. BUT TEMPS SHOULD STILL FALL INTO THE UPR 40S AT MANY INTERIOR LOCATIONS AS H85 TEMPS DIP TO ARND 6C. TUE...ALTHOUGH MOIST CYC H85 FLOW WL PERSIST...MODELS SHOW ARRIVAL OF DNVA/FAIRLY SHARP DEEP LYR QVECTOR DVGC/SUBSIDENCE IN THE WAKE OF PASSING SHRTWV DOMINATING...WITH SFC HI PRES BLDG INTO THE AREA DURING THE AFTN. SO ANY MRNG SHOWERS SHOULD DIMINISH WITH TIME DESPITE THE DIURNAL HEATING THAT WOULD NORMALLY ENHANCE PCPN CHCS. EXPECT ANOTHER RELATIVELY COOL DAY WITH LINGERING LO CLDS AND H85 TEMPS IN THE 6-8C RANGE THAT WL SUPPORT MAX TEMPS INTO THE LO 70S OVER THE SCENTRAL...WITH MAINLY 60S CLOSER TO LK SUP. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 341 PM EDT MON AUG 3 2015 BELOW AVERAGE TEMPERATUES AND A FEW SMALL CHANCES OF RAIN WILL BE THE RULE ACROSS UPPER MI INTO THIS WEEKEND. TUESDAY NIGHT...A MID-LEVEL LOW CENTERED OVER JAMES BAY WILL BEGIN A SLOW PUSH EASTWARD TUESDAY NIGHT. ANY SHOWER ACTIVITY THAT OCCURS DURING THE DAY TUESDAY AS AN ASSOCIATED TROUGH AXIS CROSSES UPPER MI SHOULD END BY TUESDAY EVENING UNDER INCREASED DRYING AND DEEP SUBSIDENCE. THE SFC GRADIENT WINDS WILL BECOME LIGHT/CALM AS A SFC RIDGE BUILDS FROM SOUTH CENTRAL CANADA TO THE WESTERN CWA. WHILE PWAT VALUES OF AROUND 0.75 INCHES WILL BE FAR FROM IDEAL FOR SUBSTANTIAL COOLING...INLAND LOCATIONS SHOULD DROP WELL INTO THE 40S GIVEN THE OVERALL COOL AIR MASS IN PLACE. UPPER 30S FOR THE TYPICAL COLDEST SPOTS WILL NOT BE OUT OF THE QUESTION FOR THE INTERIOR WEST. HAVE STEERED CLEAR OF THE COLDEST GUIDANCE FOR NOW AS ANOTHER WEAK MID-LEVEL TROUGH CROSSING THE AREA OVERNIGHT MAY BE ENOUGH TO PRODUCE SOME SCATTERED CLOUDS. BY WEDNESDAY...THE MORNING LOOKS TO BE MOSTLY SUNNY...BUT YET ANOTHER SUBLTE TROUGH LOOKS TO REACH THE WESTERN CWA LATE IN THE AFTERNOON. A SHALLOW LAYER OF MOISTURE BETWEEN 800 AND 850 HPA COMBINED WITH WEAK FORCING FROM THE TROUGH MAY BE ENOUGH TO PRODUCE LIGHT SHOWERS. IF THIS OCCURS...THE FOCUS WILL BE ON A WEAK LAKE SUPERIOR LAKE BREEZE...AND A LAKE MI/GREEN BAY LAKE BREEZE THAT SHOULD PUSH WELL INLAND ON LIGHT EASTERLY WINDS. HAVE OPTED TO ADD A SLIGHT CHANCE OF AFTERNOON SHOWERS FOR THE CENTRAL CWA AWAY FROM THE GREAT LAKES AT THIS TIME. THURSDAY...A SHORTWAVE TROUGH ERODING A RIDGE OVER THE NORTHERN PLAINS TUESDAY NIGHT IN CONJUNCTION WITH THE RIGHT ENTRANCE OF AN UPPER JET WILL INDUCE MULTIPLE AREAS OF CONVECTION ACROSS THE NORTHERN PLAINS INTO THE MID/UPPER MS VALLEY WED. LATEST GUIDANCE IS SPLIT ON THE INTENSITY OF THE NORTHERN SECTION OF THE CONVECTION...WITH THE ECMWF BEING MOST AGRESSIVE. IT APPEARS ANY NORTHERN CONVECTION WILL STRUGGLE TO TRACK WELL EAST ACROSS THE CWA AS IT ENCOUNTERS AN INCREASINGLY DRIER AIR MASS ACROSS NORTHERN WI AND WESTERN LAKE SUPERIOR. WIDELY ISOLATED SHOWERS/SPRINKLES COULD OCCUR AS THE TROUGH AXIS PASSES THURSDAY MORNING...BUT CONFIDENCE IS MUCH TOO LOW TO INTRODUCE ANY MENTION AT THIS TIME. FRIDAY THROUGH MONDAY...THE EVOLUTION OF THE SYNOPTIC PATTERN BECOMES MORE COMPLICATED BEGINNING LATE THIS WEEK. SIMPLY PUT...THE LONG TERM MODELS ARE IN LITTLE AGREEMENT. IN FACT...THE 12Z RUN OF THE GFS SHOWS A STACKED SHORTWAVE RIDGE OVER THE CWA AT 12Z SAT...WHILE THE ECMWF HAS A MID-LEVEL TROUGH LAGGING BEGIND A SFC TROUGH JUST EAST OF UPPER MI. MEANWHILE...THE CANADIAN GEM CANNOT CHOSE WHICH OF THE OTHER TWO TO FOLLOW...WITH IT MORE IN LINE WITH THE ECMWF THU INTO FRI...AND THE GFS SAT INTO SUN. MOST OF THIS IS A RESULT OF THE ECWMF LEAVING BEHIND THE SW EXTENT OF THURSDAYS TROUGH IN RESPONSE TO CONVECTIVE FEEDBACK ACROSS THE NORTHERN PLAINS. WILL STILL HEDGE TOWARD A DRIER SOLUTION FOR MOST DAYS UNTIL THINGS WORK THEMSELVES OUT IN THE GUIDANCE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 121 AM EDT TUE AUG 4 2015 EXPECT QUITE A BIT OF LOW CLOUDS TO LINGER THRU THE MORNING AS THE UPPER GREAT LAKES WILL BE DOMINATED BY A MOIST CYCLONIC NW FLOW AROUND LOW PRES NEAR HUDSON BAY. ALTHOUGH VFR CONDITIONS SHOULD BE THE RULE FOR THE MOST PART AT KIWD/KCMX/KSAW...CIGS MAY DROP INTO THE HIGH END MVFR RANGE AROUND SUNRISE GIVEN CURRENT OBS UPSTREAM TO THE NW OF LAKE SUPERIOR. EVEN IF CIGS DROP INTO THE MVFR CATEGORY... DAYTIME HEATING AND LOW-LEVEL DRYING WILL ALLOW A RETURN OF VFR CONDITIONS AT ALL TERMINALS BY LATE MORNING. UNDER DEEPER DRYING DURING THE AFTN...EXPECT CLOUDS TO SCATTER OUT AT ALL TERMINALS. WHILE ISOLD -SHRA AND/OR SPRINKLES ARE EXPECTED AT TIMES INTO THE MORNING HRS...VFR VIS SHOULD PREVAIL. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 346 PM EDT MON AUG 3 2015 EXPECT WNW WINDS UP TO 20 KTS INTO MID WEEK AROUND DEEP LOW PRESSURE NEAR HUDSON BAY. A WEAK PRES GRADIENT WILL DOMINATE DURING THE LATE WEEK...RESULTING IN WINDS UNDER 20 KTS. NO GALES SEEN ANYTIME SOON. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...KLUBER AVIATION...ROLFSON MARINE...KC
AREA FORECAST DISCUSSION
NWS DULUTH MN
847 PM CDT WED AUG 5 2015 .UPDATE... ISSUED AT 847 PM CDT WED AUG 5 2015 LATEST HRRR RUNS INDICATE A SLOWER ONSET OF SHOWERS AND STORMS TO THE WESTERN EDGE OF THE FORECAST AREA UNTIL 12Z. DRY AIR FROM HIGH PRESSURE OVER LAKE SUPERIOR WILL WIN OUT OVER THE RAIN AND ADJUSTED ACCORDINGLY. UPDATE ISSUED AT 657 PM CDT WED AUG 5 2015 LATEST SHORT TERM HIRES MODELS INCLUDING THE NMM/ARW DELAY THE ONSET OF SHOWERS AND STORMS TO AFTER 09Z. HAVE MADE SOME ADJUSTMENTS TO ACCOUNT FOR THAT TREND. REFLECTIVITY SHOWING UP ON KDLH 88D ATTM ARE CLOUDS WITH A MINIMUM 12K FT BASE. REST OF THE FORECAST ON TRACK. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 313 PM CDT WED AUG 5 2015 A WARM AIR ADVECTION REGIME RETURNS TO THE FORECAST AREA OVERNIGHT AS WARM FRONT LIFTS NORTH INTO CANADA...AND A VORT MAX/H85 LOW TRANSLATES EAST ACROSS NORTH DAKOTA/SOUTHERN MANITOBA...REACHING THE NW CORNER OF MN BY DAYBREAK THURSDAY. THE VORT MAX THEN DIMINISHES/STALLS OVER NW MINNESOTA MONDAY MORNING WHILE BECOMING ABSORBED BY ANOTHER FAST APPROACHING WAVE IN THE DAKOTAS. THIS RAPIDLY DEEPENING WAVE...IN A REGION OF STRONG UPPER LVL DIVERGENCE...BECOMES A CLOSED LOW AND PUSHES INTO WESTERN MINNESOTA BY THURSDAY EVENING. THE NORTHLAND WILL BE POSITIONED IN A SOUTHERLY FLOW WITH INCREASING MOISTURE AND INSTABILITY AHEAD OF THE LOW THROUGH THE DAY THURSDAY. PWATS INCREASE TO NEAR 2 INCHES THURSDAY WHILE DEW POINTS SURGE INTO THE 60S OVER NORTH CENTRAL MN. A FEW STORMS COULD BE STRONG TO LOW-END SEVERE THURSDAY...MAINLY OVER NORTH-CENTRAL MN WHERE THE LATEST NAM IS SHOWING AROUND 2000 J/KG OF CAPE DEVELOPING IN THE AFTERNOON. HOWEVER..THE MAIN THREAT WITH ANY STORMS THURSDAY LOOKS TO BE PERIOD OF VERY HEAVY RAINFALL AND LOCALIZED FLOODING. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 313 PM CDT WED AUG 5 2015 THE MAIN CONCERN IN THE LONG TERM WILL BE AN APPROACHING LOW PRESSURE SYSTEM THURSDAY NIGHT WITH ASSOCIATED FRONTAL BOUNDARY. MODELS ARE IN AGREEMENT AS FAR AS THE OVERALL PATTERN IS CONCERN FRIDAY AND SATURDAY... INCREASING DEWPOINTS TO THE 60S... SOLID WARM AIR ADVECTION AND A GENERAL LIKELIHOOD OF SHOWERS AND STORMS. HOWEVER MODELS DIVERGE ON THE EVENTUAL PATH OF THE LOW AND WHERE THE BULLS- EYE OF THE QPF WILL BE. 12Z NAM12 HAS THE LOW TAKING A NOSE DIVE TO SOUTHERN MINNESOTA AND IOWA WITH A LINE OF PRECIP BREAKING APART ACROSS THE NORTHLAND... THE GFS40 STALLING BUT ALSO MARCHING THROUGH SOUTHERN MINNESOTA... AND THE ECMWF STICKING TO A MORE NORTHERN SOLUTION ACROSS CENTRAL PARTS OF THE STATE AND NORTHERN WISCONSIN. OVERALL DELAYED THE ONSET OF INITIAL FRIDAY PRECIP ALONG THE WARM FRONT IN COLLABORATION WITH NEIGHBORING OFFICES. EXPECT ANOTHER CHANCE OF SHOWERS AND STORMS TO MOVE THROUGH SATURDAY WITH THE SECOND BOUNDARY... BUT QPF WILL LIKELY BE HIGHEST ON FRIDAY. DEWPOINTS WILL DROP BACK INTO THE MORE COMFORTABLE 50S FOR MOST OF THE CWA BY MONDAY AS A HIGH PRESSURE RIDGE BUILDS BACK IN ACROSS THE UPPER MIDWEST... THOUGH EXPECT THE SUMMER WARMTH TO REMAIN... WITH MID TO UPPER 70 HIGHS IN THE FORECAST NEXT WORK WEEK. AFTER A SHORTWAVE BRINGS A SHOT OF SHOWERS ACROSS OUR SOUTH MONDAY... THE REST OF THE WEEK LOOKS MOSTLY DRY AND PARTLY CLOUDY TO SUNNY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 632 PM CDT WED AUG 5 2015 MODELS CONTINUE TO DELAY THE ONSET OF PCPN AND HAVE MADE THOSE ADJUSTMENTS TO THE FORECAST. STORMS SHOULD REACH INL FIRST AND SLOWLY SPREAD OVER THE REST OF THE TERMINALS...EXCEPT HYR WHICH WILL NOT SEE STORMS THROUGH THE FORECAST PERIOD. VFR IS EXPECTED. && .PRELIMINARY POINT TEMPS/POPS... DLH 54 72 61 71 / 0 30 60 50 INL 54 76 59 72 / 10 50 50 40 BRD 60 76 62 77 / 10 60 80 50 HYR 53 79 62 73 / 0 30 60 60 ASX 55 76 60 74 / 0 10 40 60 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...NONE. && $$ UPDATE...GSF SHORT TERM...GRANING LONG TERM...MCLOVIN AVIATION...GSF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
907 PM CDT WED AUG 5 2015 .UPDATE... OVERALL SOMEWHAT QUIET BUT WARMER NIGHT TONIGHT. EXPECT THE LINGERING STORMS THAT HAVE CLIPPED THE GOLDEN TRIANGLE AREA TO MOVE OUT IN THE NEXT HOUR OR SO WHILE THE REST OF THE AREA SHOULD REMAIN DRY FOR THE MOST PART TONIGHT. WATER VAPOR IMAGERY INDICATES S/WV SPARKING CONVECTION IN NW AR THAT COULD CLIP SOME OF THE NW AREAS BEFORE 12Z. HI-RES ARW/NMM INDICATE THIS ACTIVITY WILL WEAKEN OVER THE NEXT FEW HOURS AS IT APPROACHES OUR NW WHILE HRRR INDICATES SOME COULD SNEAK IN BUT MUCH WEAKER. DECIDED TO REMOVE POPS FOR NW UNTIL AFTER 12Z WHEN BETTER LIFT WILL MOVE IN FROM THE QUICK UPPER DISTURBANCE MOVING IN THE NW FLOW ALOFT THROUGH THE MID/LOWER MS VALLEY. 00Z REGIONAL SOUNDINGS INDICATE BETTER LOW LEVEL MOISTURE AND PWATS IN THE 1.6 TO 2 INCH RANGE...WHICH WILL AID IN ANOTHER DAY OF GOOD RAIN/STORM CHANCES TOMORROW. OVERALL SLIGHTLY ADJUSTED LOWS UPWARD OVERNIGHT DUE TO CURRENT TRENDS OF LOW LEVEL MOISTURE/CLOUDS. REST OF THE FORECAST IS ON TRACK. /DC/ && .AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. ISOLATED TO SCATTERED TSRA/VCTS ARE POSSIBLE THURS AFTERNOON AFTER 15-16Z, WHICH MAY BRING BRIEF CATEGORY REDUCTIONS AND GUSTY WINDS. /DC/26/ && .PREV DISCUSSION... /ISSUED 401 PM CDT WED AUG 5 2015/ DISCUSSION... THROUGH THURSDAY NIGHT... MOISTURE CONTINUES TO INCREASE AND THIS IS RESULTING IN INCREASED HEAT STRESS AS WE GO INTO THURSDAY. HEAT INDEX VALUES WILL BE HIGH ENOUGH TOMORROW TO WARRANT THE ISSUANCE OF A HEAT ADVISORY FOR THE DELTA REGION. MOISTURE WILL CONTINUE TO BE ON THE INCREASE THURSDAY AS A STRONG SHORT WAVE MOVES ACROSS THE REGION. THIS ALONG WITH PWATS AROUND 2.0 INCHES SHOULD ALLOW FOR DECENT CHANCES FOR SHOWERS AND STORMS ACROSS MAINLY EASTERN ZONES. SOME STORMS COULD REACH SEVERE LIMITS TOMORROW AFTERNOON AND EVENING. AS THE SHORT WAVE MOVES SOUTH EXPECT THE SHOWER AND THUNDERSTORM ACTIVITY TO DIMINISH BY THE EVENING HOURS. MID/UPPER LEVEL HEIGHTS WILL INCREASE ACROSS THE AREA THURSDAY NIGHT INTO FRIDAY WITH VERY WARM OVERNIGHT LOWS IN THE MID 70S. /15/27/ FRIDAY THROUGH TUESDAY...THE MAIN FOCUS THROUGH THE LONG TERM REMAINS THE NEAR RECORD HEAT BUILDING THROUGH THE WEEKEND COMBINED WITH ENOUGH HUMIDITY TO RESULT IN DANGEROUS HEAT INDEX VALUES. FRIDAY A SUBTLE SHORTWAVE WILL ROUND THE EASTERN PERIPHERY OF A BROAD HIGH CENTERED OVER THE SOUTHERN PLAINS. THIS FEATURE ALONG WITH DAYTIME HEATING AND OUR MOIST AIR MASS WILL LEAD TO AT LEAST ISOLATED COVERAGE OF STORMS OVER THE EASTERN HALF OF OUR CWA. A FEW OF THE STORMS WILL BE STRONG AND CAPABLE OF WIND GUSTS TO 50 MPH. THE ASSOCIATED CLOUD COVER SHOULD HOLD AFTERNOON HIGHS IN THE MID 90S OVER OUR EAST BUT WARMER TEMPERATURES AND LOWER CHANCES FOR RAIN ARE EXPECTED OVER OUR WEST. MAXIMUM HEAT INDEX VALUES ARE EXPECTED BETWEEN 106 AND 110 WITH HIGHEST VALUES OVER THE DELTA. SATURDAY THE LARGE MID LEVEL HIGH WILL BEGIN SHIFTING EAST WHILE STRENGTHENING OVER OUR CWA. ISOLATED AFTERNOON AND EARLY EVENING STORMS WILL BE HARD TO RULE OUT OVER OUR EASTERN ZONES BUT GENERALLY HOTTER AND DRIER CONDITIONS ARE EXPECTED FOR OUR CWA. AFTERNOON HIGHS OVER MUCH OF OUR WEST WILL BE AROUND 100F WITH UPPER 90S EXPECTED ELSEWHERE. THESE TEMPERATURES WILL COMBINE WITH LOWER 70 DEW POINTS TO RESULT IN HEAT INDEX VALUES BETWEEN 106 AND 110 AREAWIDE. THE TWO HOTTEST DAYS OF THE LONG TERM PERIOD ARE STILL EXPECTED TO BE SUNDAY AND MONDAY WHERE NEAR RECORD AFTERNOON HIGHS CAN BE EXPECTED FOR MUCH OF THE AREA. RECORD HIGHS RUN IN THE LOWER 100S AT MOST LOCATIONS SUNDAY AND MONDAY AND THE LIKELIHOOD OF REACHING AND EXCEEDING 100F EACH DAY IS INCREASING ESPECIALLY OVER OUR DELTA REGION. BOTH THE ECMWF AND GFS CONTINUE TO SHOW AN INTENSE LOW LEVEL THERMAL RIDGE DEVELOPING OVER THE ARKLAMISS WITH H850 TEMPS IN THE 24-27 DEG C RANGE. A FEW LOCATIONS MAY SEE SURFACE TEMPERATURES REACH THE 104 TO 107 DEG MARK...ESPECIALLY OVER THE DELTA REGION. AS THE HEAT PEAKS EACH AFTERNOON DRIER AIR MAY MIX DOWN AND HELP OFFSET THE HIGH HUMIDITY BUT...HEAT INDEX VALUES WILL LIKELY EXCEED 105 SUNDAY AND MONDAY. A HEAT ADVISORY WILL LIKELY BE NEEDED THIS WEEKEND FOR MUCH OF THE AREA AND AN EXCESSIVE HEAT WARNING MAY BE NEEDED IF HIGHER AFTERNOON HUMIDITY CAN BE MAINTAINED. BOTH THE GFS AND ECMWF SHOW A MORE SUBSTANTIAL SHORTWAVE DROPPING AROUND THE EASTERN PERIPHERY OF THE SUBTROPICAL HIGH TUESDAY. THIS SHORTWAVE WILL SUPPORT A SURFACE LOW WELL TO OUR NORTHEAST BUT A WEAK ASSOCIATED COLD FRONT LOOKS TO SAG INTO OUR CWA TUESDAY. NEITHER MODEL DEPICTS MUCH QPF WITH THE FRONT BUT SLIGHTLY LESS OPPRESSIVE HEAT IS EXPECTED TUESDAY. /22/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 76 96 76 99 / 11 23 23 21 MERIDIAN 73 93 74 97 / 11 34 33 31 VICKSBURG 76 98 76 99 / 10 16 17 9 HATTIESBURG 77 96 76 98 / 11 27 23 29 NATCHEZ 77 95 76 96 / 9 11 13 9 GREENVILLE 79 97 76 99 / 11 25 23 16 GREENWOOD 76 94 75 97 / 11 37 30 22 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...HEAT ADVISORY FROM 11 AM TO 7 PM CDT THURSDAY FOR MSZ018-019- 025>027-034>036-040>042-047. LA...HEAT ADVISORY FROM 11 AM TO 7 PM CDT THURSDAY FOR LAZ007>009-015- 016-023>026. AR...HEAT ADVISORY FROM 11 AM TO 7 PM CDT THURSDAY FOR ARZ074-075. && $$ DC/26/15/22
AREA FORECAST DISCUSSION
NWS JACKSON MS
1038 AM CDT TUE AUG 4 2015 .UPDATE... MIXING IS NOT AS STRONG AS IN RECENT DAYS AND BOUNDARY LAYER MOISTURE IS ON THE INCREASE. DEEP LAYER MOISTURE IS STILL UNSEASONABLY LOW AT KJAN WITH THE OBSERVED PRECIPITABLE WATER VALUE AT 1.36 INCHES THIS MORNING. KLIX CAME IN AT 1.61 INCHES...BUT THAT IS MOSTLY IN RESPONSE TO INCREASED LOW LEVEL MOISTURE WITH MID LEVELS STILL LOOKING RATHER HARSH FOR DEEP CONVECTIVE DEVELOPMENT. NONETHELESS...WITH A DISTURBANCE OVER SE LA AND INCREASING COASTAL MOISTURE CONVERGENCE...WILL BUY INTO THE HRRR GUIDANCE INDICATION OF SHOWER DEVELOPMENT THIS AFTERNOON ALONG THE HWY 98 CORRIDOR AND INTRODUCE MENTION OF ISOLATED SHOWER/TSTM ACTIVITY. OTHERWISE...ANOTHER HOT DAY IS IN STORE. TEMPS/DEWPOINTS ARE PRETTY MUCH ON TRACK FOR TODAY AND NO SIGNIFICANT ADJUSTMENTS ARE NECESSARY. ONE THING TO NOTE REGARDING THE HEAT FOR THE WEEKEND...MOST RECENT GLOBAL GUIDANCE IS SUGGESTING H850 TEMPS WILL EXCEED 26 DEG C AT SOME POINT SAT/SUN. IF THESE VALUES VERIFY...WOULD EXPECT DRY BULB TEMPERATURE READINGS TO EXCEED 105 DEG F IN A FEW LOCATIONS. /EC/ && .AVIATION...EXPECT VFR CONDITIONS TO CONTINUE THROUGH THE PERIOD AT ALL TAF SITES. THE WINDS WILL GENERALLY BE LIGHT AND VARIABLE./15/17/ && .PREV DISCUSSION... /ISSUED 419 AM CDT TUE AUG 4 2015/ SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...TODAY WILL BE ANOTHER HOT DAY ACROSS THE ARKLAMISS WITH HIGHS CLIMBING CLOSE TO 100 DEGREES ONCE AGAIN. MOISTURE WILL BEGIN TO INCREASE ACROSS THE WEST AND SOUTH THIS AFTERNOON AND WITH THE INCREASE IN THE RH`S...HEAT INDICES WILL CLIMB CLOSE TO 105 IN THE WEST. WITH THE INCREASE IN HUMIDITY...OVERNIGHT LOWS WILL ONLY FALL INTO THE LOW TO MID 70S AS OPPOSED TO THE MID/UPPER 60S WE HAVE BEEN SEEING. MOISTURE WILL CONTINUE TO INCREASE ON WEDNESDAY WITH PWATS CLIMBING ABOVE 1.8 INCHES OVER MOST OF THE AREA. WITH THE INCREASE IN MOISTURE COMBINING WITH AFTERNOON HEATING AND A WEAK SHORT...THUNDERSTORM CHANCES WILL ALSO INCREASE DURING THE AFTERNOON AND EVENING HOURS OVER MUCH OF THE AREA. THE HEAT INDICES WILL CLIMB ABOVE 105 MAINLY ALONG AND WEST OF THE RIVER...SO A HEAT ADVISORY MAY BE NEEDED FOR THESE AREAS. WITH SHORT WAVE ENERGY CONTINUING ACROSS THE AREA THROUGH THE NIGHT...THE THUNDERSTORM CHANCES WILL CONTINUE WEDNESDAY NIGHT INTO THURSDAY MORNING./15/ LONG TERM...THURSDAY THROUGH MONDAY...MODELS ARE IN GOOD AGREEMENT THAT THURSDAY WILL BE THE COOLEST DAY WITH THE GREATEST CHANCE FOR RAIN OF THE LONG TERM PERIOD. SUNDAY AND MONDAY WILL BE THE TWO HOTTEST DAYS OF THE LONG TERM. THURSDAY OUR CWA WILL BE DOWNSTREAM OF A LARGE 594DAM HIGH CENTERED OVER THE DESERT SOUTHWEST. A SHORTWAVE TOPPING THIS RIDGE WILL MOVE FROM THE MID MISSISSIPPI VALLEY ACROSS THE TENNESSEE VALLEY BY THURSDAY EVENING. CONVECTION ASSOCIATED WITH THIS SHORTWAVE WILL SPREAD SOUTH OVER OUR CWA DURING THE HEAT OF THE DAY. THE GREATEST POPS WL BE CARRIED OVER THE NORTHEAST HALF OF THE AREA THROUGH THURSDAY WITH LOWEST POPS OVER OUR WEST. WL HAVE A MOIST AIR MASS BACK OVER OUR CWA WITH PWATS BETWEEN 1.75-2.0 INCHES AND SURFACE DEW POINTS IN THE LOW TO MID 70S. OTHER ENVIRONMENTAL PARAMETERS SUGGEST A FEW STRONG STORMS WITH WIND GUSTS OF 40 TO 50 MPH WL BE POSSIBLE THURSDAY AFTERNOON AND EVENING. THE SHORTWAVE WILL SHIFT EAST OF OUR REGION THURSDAY NIGHT BUT THE WEAK SURFACE LOW ASSOCIATED WITH THE SHORTWAVE WILL TRACK EAST AS WELL AND TRY TO DROP A WEAK COLD FRONT INTO OUR CWA. THIS WILL HELP PROLONG LOW CHANCES FOR RAIN OVER OUR NORTHERN ZONES THURSDAY NIGHT. THE STALLED FRONT IS EXPECTED TO BE JUST NORTH OF HIGHWAY 82 FRIDAY AND SERVE AS A FOCUS FOR CONVECTION BEFORE DISSIPATING BY FRIDAY EVENING. MID LEVEL RIDGING WILL CONTINUE TO LIMIT COVERAGE TO ISOLATED IN THE WEST WITH SCATTERED COVERAGE IN THE EAST. SATURDAY THE LARGE MID LEVEL HIGH WILL BEGIN BUILDING EAST OVER OUR CWA WHILE THE SURFACE RIDGE SHIFTS FROM THE GULF COAST TO THE CENTRAL GULF. THIS WILL RESULT IN HOTTER AND DRIER CONDITIONS OVER OUR CWA THROUGH THE WEEKEND INTO THE START OF THE WORK WEEK. HIGHS SATURDAY WILL TOP OUT IN THE MID TO UPPER 90S. HIGHS WILL REACH OR EXCEED 100F AT SEVERAL LOCATIONS SUNDAY AND MONDAY. THE HEAT WILL COMBINE WITH HIGH HUMIDITY TO RESULT IN HEAT INDEX VALUES EXCEEDING 105 SATURDAY. EVEN HIGHER HEAT INDEX VALUES ARE EXPECTED SUNDAY AND MONDAY. A HEAT ADVISORY WILL LIKELY BE NEEDED THIS WEEKEND FOR MUCH OF THE AREA. /22/ && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1014 AM MDT TUE AUG 4 2015 .UPDATE... NEGATIVELY TILTED UPPER TROF SLOWLY DRIFTING NORTHEAST OVER NORTHERN WYOMING IS CREATING A VERY FAVORABLE HEAVY RAIN PATTERN FOR SOUTHERN MONTANA AND NORTHERN WYOMING TODAY. PRECIPITABLE WATER VALUES OVER 1.25 INCHES AND SLOW STORM MOVEMENT COMBINED WITH PERSISTENT DIVERGENCE ALOFT WILL BRING THE POTENTIAL FOR LOCALLY HEAVY RAIN WITH ANY STORMS TODAY...ESPECIALLY FROM BILLINGS EAST WHERE FLASH FLOODING CONCERNS ARE INCREASING. ALREADY HAVE A FLASH FLOOD WARNING OUT FOR BIG HORN COUNTY WITH A PERSISTENT LINE OF STRONG THUNDERSTORMS THERE. AS A MID LEVEL IMPULSE WORKS IN FROM THE WEST THIS AFTERNOON WILL SEE A LINE OF SHOWERS AND STORMS WORK ACROSS THE AREA FROM WEST TO EAST INTO THE LATE EVENING. WIDESPREAD PRECIPITATION VALUES OF .2 TO .5 INCHES CAN BE EXPECTED TODAY...WITH LOCALLY 1 TO 2 INCHES WITH STRONGER STORMS. SMALL HAIL IS POSSIBLE WITH STRONGER STORMS TODAY ALONG WITH WIND GUSTS OF 40 TO 50 MPH...BUT THE MAIN THREAT WILL BE THE HEAVY RAINFALL AND INTENSE LIGHTNING. ADDED MENTION OF HEAVY RAIN WEST TO INCLUDE BILLINGS AND ROUNDUP. INCREASED PRECIPITATION CHANCES THIS MORNING WITH AN EARLY START TO CONVECTION. NO CHANGE TO GOING FLASH FLOOD WATCH AS IT IS LOCATED IN THE MOST FAVORABLE POSITION FOR STRONG SLOW MOVING STORMS...HOWEVER AS WE HAVE SEEN ALREADY IN BIG HORN COUNTY WE CAN`T RULE OUT LOCALIZED FLASH FLOODING FURTHER WEST INCLUDING THE BILLINGS AREA TODAY. CHAMBERS && .SHORT TERM...VALID FOR TDY AND WED... THE PATTERN HAS TURNED FROM HOT AND DRY TO COOLER AND MORE UNSETTLED. THE HOT UPPER RIDGE OF THE LAST SEVERAL DAYS HAS BEEN PUSHED EAST BY AN ADVANCING UPPER TROUGH MOVING IN FROM THE WEST. THIS TROUGH WILL PUSH ACROSS WESTERN ZONES THIS MORNING...CENTRAL ZONES EARLY THIS AFTERNOON...AND THE EAST THIS AFTERNOON AND EVENING. THE STRONGEST ENERGY WILL SLIDE ACROSS WYOMING...BUT THE NORTHERN EXTENT OF THE TROUGH STRETCHED TO SOUTHERN CANADA...SO THERE WILL BE ADEQUATE FORCING AND MOISTURE FOR CONVECTION. AS FAR AS MOISTURE IS CONCERNED...PWATS WERE ADVERTISED AT 1.5 INCHES OVER THE EAST. THIS IS 3 STANDARD DEVIATIONS ABOVE NORMAL. PERSISTENT SOUTHEAST WINDS HAVE BROUGHT DEWPOINTS UP INTO THE 50S OVER THE EAST. STORMS WILL FORM THIS MORNING OVER WESTERN ZONES...SPREAD IN CENTRAL ZONES LATE MORNING INTO EARLY AFTERNOON...THEN FORM OVER THE EAST THIS AFTERNOON AND EVENING. SHEAR WILL BE WEAK...LESS THAN 30KTS...SO SEVERE NOT A HUGE CONCERN...OTHER THAN MICROBURST WINDS WITH COLLAPSING CELLS. WEAK SHEAR AND STEERING WINDS WILL LEAD TO SLOW MOVING PULSING CELLS THAT WILL HAVE HIGH INTENSITY RAINFALL RATES OVER THE EAST. THE VERY HEAVY RAIN STORMS MAY EVEN BE AS FAR WEST AS BIG HORN AND EASTERN YELLOWSTONE COUNTY WITH PWATS AROUND AN INCH. HRRR HAS CELLS GOING UP OVER NORTHERN SHERIDAN COUNTY AND SOUTHERN BIG HORN COUNTY AROUND NOON AND THEN DEVELOPS UNORGANIZED CONVECTION FARTHER EAST THIS AFTERNOON. WILL LEAVE FLASH FLOOD WATCH IN EFFECT. HIGH TEMPERATURES WILL BE COOLER OVER WESTERN AND CENTRAL ZONES WITH EARLIER CONVECTION DEVELOPMENT. THE EAST WILL HAVE ENOUGH CLOUD BREAKS TO WARM BACK UP TO THE UPPER 80S. THE STORMS ARE PROJECTED TO EXIT THE EAST OVERNIGHT. WEDNESDAY COULD POTENTIALLY BE ANOTHER ACTIVE DAY AS A SHORTWAVE OFF THE CALIFORNIA COAST GETS DRIVEN ACROSS THE NORTHERN ROCKIES. THIS SYSTEM WILL HAVE ACCESS TO A TROPICAL LINK AS EVIDENCED BY WATER VAPOR...SO THERE WILL BE JUICE FOR CONVECTION. THE DEEPEST MOISTURE LOOKS TO SLIDE TO THE SOUTH. SHEAR WILL BE STRONGER...AROUND 40KTS...AND CAPES RISE TO AROUND 800J/KG. CERTAINLY LOOKS LIKE ANOTHER GOOD CHANCE OF THUNDERSTORMS...WITH A SEVERE STORM OR TWO A DEFINITE POSSIBILITY. STORMS WILL BE HEAVY RAINERS...WITH THE TROPICAL CONNECTION AND PWATS ADVERTISED AT AROUND AN INCH. TWH .LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON... A FEW CHANGES WERE MADE TO THE EXTENDED FORECAST PERIOD THIS MORNING...MAINLY CENTERED AROUND TIMING OF THE WEDNESDAY SYSTEM EXITING THE REGION ON THURSDAY. FOLLOWING THE EXIT OF THE SYSTEM ON THURSDAY...THE RETURN OF UPPER LEVEL RIDGING WILL KEEP THE PATTERN DRY THROUGH SATURDAY EVENING...WHEN THE NEXT PACIFIC TROF PUSHES INTO THE REGION. THIS IS PROGGED TO BE ANOTHER WET SYSTEM...BRINGING PACIFIC MOISTURE...AND TAPPING INTO MONSOONAL FLOW AS WELL. THE WAVE HOWEVER DOES NOT SEEM TO BE HOLDING TOGETHER VERY WELL...GENERALLY LOSING ORGANIZATION AND ENERGY AS IT APPROACHES. THEREFORE HAVE KEPT POPS FAIRLY LOW...EVEN THOUGH IT HAS BEEN QUITE CONSISTENT FROM RUN TO RUN. THIS WAVE...IF IT CONTINUES TO HOLD TOGETHER...WILL CROSS THE REGION THROUGH SUNDAY...BRINGING SHOWER AND THUNDERSTORM POTENTIAL ACROSS THE REGION ONCE AGAIN. TIMING ALSO SHOULD LEAD TO COOLER TEMPS FOR SUNDAY...BUT STILL IN LOW 80S AT THIS POINT. AT THIS POINT MODELS DIVERGE A BIT...BUT DO AGREE ON SOME DEGREE OF SOUTHWEST FLOW INTO THE WESTERN MOUNTAINS...AND UPPER LEVEL RIDGING BRINGING TEMPS APPROACHING 90 DEGREES ACROSS THE REGION AGAIN. AAG && .AVIATION... NUMEROUS SHOWERS AND THUNDERSTORMS EXPECTED ACROSS THE AREA TODAY. EMBEDDED STORMS WILL MAKE DIFFICULT FLIGHT CONDITIONS AT TIMES INTO THIS EVENING. VERY HEAVY RAINFALL WILL CREATE MVFR TO LOCAL IFR CONDITIONS NEAR SHOWERS AND STORMS. A COLD FRONT WILL PUSH THIS ACTIVITY EAST THIS EVENING WITH VFR CONDITIONS PREVAILING ACROSS THE AREA OVERNIGHT. CHAMBERS && .PRELIMINARY POINT TEMP/POPS... TDY WED THU FRI SAT SUN MON ------------------------------------------------------- BIL 079 059/084 058/085 056/083 057/085 058/083 059/089 6/T 34/T 52/T 11/U 13/T 32/T 21/B LVM 077 053/080 050/081 049/083 051/081 052/080 052/086 6/T 35/T 52/T 11/B 13/T 44/T 32/T HDN 084 056/087 057/087 054/085 055/088 057/085 057/091 7/T 43/T 52/T 11/B 12/T 22/T 21/U MLS 089 059/088 061/086 058/084 057/086 060/083 059/090 7/T 82/T 54/T 11/B 13/T 33/T 31/B 4BQ 088 058/088 059/085 057/083 057/085 059/084 058/089 7/T 72/T 52/T 21/U 12/T 33/T 31/B BHK 088 058/086 059/082 056/081 054/083 057/080 056/085 4/T 82/T 44/T 22/W 12/T 44/T 32/T SHR 079 052/086 054/083 052/083 054/085 055/082 054/088 6/T 43/T 52/T 11/U 13/T 32/T 21/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...FLASH FLOOD WATCH IN EFFECT THROUGH THIS EVENING FOR ZONES 31>33-36-37-58. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
348 AM MDT TUE AUG 4 2015 .SHORT TERM...VALID FOR TDY AND WED... THE PATTERN HAS TURNED FROM HOT AND DRY TO COOLER AND MORE UNSETTLED. THE HOT UPPER RIDGE OF THE LAST SEVERAL DAYS HAS BEEN PUSHED EAST BY AN ADVANCING UPPER TROUGH MOVING IN FROM THE WEST. THIS TROUGH WILL PUSH ACROSS WESTERN ZONES THIS MORING...CENTRAL ZONES EARLY THIS AFTERNOON...AND THE EAST THIS AFTERNOON AND EVENING. THE STRONGEST ENERGY WILL SLIDE ACROSS WYOMING...BUT THE NORTHERN EXTENT OF THE TROUGH STRETCHED TO SOUTHERN CANADA...SO THERE WILL BE ADEQUATE FORCING AND MOISTURE FOR CONVECTION. AS FAR AS MOISTURE IS CONCERNED...PWATS WERE ADVERTISED AT 1.5 INCHES OVER THE EAST. THIS IS 3 STANDARD DEVIATIONS ABOVE NORMAL. PERSISTENT SOUTHEAST WINDS HAVE BROUGHT DEWPOINTS UP INTO THE 50S OVER THE EAST. STORMS WILL FORM THIS MORNING OVER WESTERN ZONES...SPREAD IN CENTRAL ZONES LATE MORNING INTO EARLY AFTERNOON...THEN FORM OVER THE EAST THIS AFTERNOON AND EVENING. SHEAR WILL BE WEAK...LESS THAN 30KTS...SO SEVERE NOT A HUGE CONCERN...OTHER THAN MICROBURST WINDS WITH COLLAPSING CELLS. WEAK SHEAR AND STEERING WINDS WILL LEAD TO SLOW MOVING PULSING CELLS THAT WILL HAVE HIGH INTENSITY RAINFALL RATES OVER THE EAST. THE VERY HEAVY RAIN STORMS MAY EVEN BE AS FAR WEST AS BIG HORN AND EASTERN YELLOWSTONE COUNTY WITH PWATS AROUND AN INCH. HRRR HAS CELLS GOING UP OVER NORTHERN SHERIDAN COUNTY AND SOUTHERN BIG HORN COUNTY AROUND NOON AND THEN DEVELOPS UNORGANIZED CONVECTION FARTHER EAST THIS AFTERNOON. WILL LEAVE FLASH FLOOD WATCH IN EFFECT. HIGH TEMPERATURES WILL BE COOLER OVER WESTERN AND CENTRAL ZONES WITH EARLIER CONVECTION DEVELOPMENT. THE EAST WILL HAVE ENOUGH CLOUD BREAKS TO WARM BACK UP TO THE UPPER 80S. THE STORMS ARE PROJECTED TO EXIT THE EAST OVERNIGHT. WEDNESDAY COULD POTENTIALLY BE ANOTHER ACTIVE DAY AS A SHORTWAVE OFF THE CALIFORNIA COAST GETS DRIVEN ACROSS THE NORTHERN ROCKIES. THIS SYSTEM WILL HAVE ACCESS TO A TROPICAL LINK AS EVIDENCED BY WATER VAPOR...SO THERE WILL BE JUICE FOR CONVECTION. THE DEEPEST MOISTURE LOOKS TO SLIDE TO THE SOUTH. SHEAR WILL BE STRONGER...AROUND 40KTS...AND CAPES RISE TO AROUND 800J/KG. CERTAINLY LOOKS LIKE ANOTHER GOOD CHANCE OF THUNDERSTORMS...WITH A SEVERE STORM OR TWO A DEFINITE POSSIBILITY. STORMS WILL BE HEAVY RAINERS...WITH THE TROPICAL CONNECTION AND PWATS ADVERTISED AT AROUND AN INCH. TWH .LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON... A FEW CHANGES WERE MADE TO THE EXTENDED FORECAST PERIOD THIS MORNING...MAINLY CENTERED AROUND TIMING OF THE WEDNESDAY SYSTEM EXITING THE REGION ON THURSDAY. FOLLOWING THE EXIT OF THE SYSTEM ON THURSDAY...THE RETURN OF UPPER LEVEL RIDGING WILL KEEP THE PATTERN DRY THROUGH SATURDAY EVENING...WHEN THE NEXT PACIFIC TROF PUSHES INTO THE REGION. THIS IS PROGGED TO BE ANOTHER WET SYSTEM...BRINGING PACIFIC MOISTURE...AND TAPPING INTO MONSOONAL FLOW AS WELL. THE WAVE HOWEVER DOES NOT SEEM TO BE HOLDING TOGETHER VERY WELL...GENERALLY LOSING ORGANIZATION AND ENERGY AS IT APPROACHES. THEREFORE HAVE KEPT POPS FAIRLY LOW...EVEN THOUGH IT HAS BEEN QUITE CONSISTENT FROM RUN TO RUN. THIS WAVE...IF IT CONTINUES TO HOLD TOGETHER...WILL CROSS THE REGION THROUGH SUNDAY...BRINGING SHOWER AND THUNDERSTORM POTENTIAL ACROSS THE REGION ONCE AGAIN. TIMING ALSO SHOULD LEAD TO COOLER TEMPS FOR SUNDAY...BUT STILL IN LOW 80S AT THIS POINT. AT THIS POINT MODELS DIVERGE A BIT...BUT DO AGREE ON SOME DEGREE OF SOUTHWEST FLOW INTO THE WESTERN MOUNTAINS...AND UPPER LEVEL RIDGING BRINGING TEMPS APPROACHING 90 DEGREES ACROSS THE REGION AGAIN. AAG && .AVIATION... SHOWERS AND THUNDERSTORMS OVERSPREAD THE ENTIRE REGION TODAY...WITH LOCAL MVFR CONDITIONS AND FREQUENT MOUNTAIN OBSCURATIONS. WINDS WILL SHIFT FROM EASTERLY TO WEST- NORTHWEST...WITH GUSTS OF 15-25 KNOTS...AS DISTURBANCE CROSSES THE REGION TODAY. AAG && .PRELIMINARY POINT TEMP/POPS... TDY WED THU FRI SAT SUN MON ------------------------------------------------------- BIL 079 059/084 058/085 056/083 057/085 058/083 059/089 6/T 34/T 52/T 11/U 13/T 32/T 21/B LVM 082 053/080 050/081 049/083 051/081 052/080 052/086 6/T 35/T 52/T 11/B 13/T 44/T 32/T HDN 084 056/087 057/087 054/085 055/088 057/085 057/091 7/T 43/T 52/T 11/B 12/T 22/T 21/U MLS 090 059/088 061/086 058/084 057/086 060/083 059/090 7/T 82/T 54/T 11/B 13/T 33/T 31/B 4BQ 088 058/088 059/085 057/083 057/085 059/084 058/089 7/T 72/T 52/T 21/U 12/T 33/T 31/B BHK 088 058/086 059/082 056/081 054/083 057/080 056/085 4/T 82/T 44/T 22/W 12/T 44/T 32/T SHR 079 052/086 054/083 052/083 054/085 055/082 054/088 6/T 43/T 52/T 11/U 13/T 32/T 21/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...FLASH FLOOD WATCH IN EFFECT FROM NOON MDT TODAY THROUGH THIS EVENING FOR ZONES 31>33-36-37-58. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
704 PM CDT WED AUG 5 2015 .SHORT TERM...(TONIGHT THROUGH THURSDAY) ISSUED AT 406 PM CDT WED AUG 5 2015 MAP ANALYSIS INDICATES UPPER TROPOSPHERIC RIDGING OVER THE WESTERN TWO-THIRDS OF THE CONUS...AND A TROUGH OVER THE EAST. AN UPPER TROPOSPHERIC SHORT WAVE IS ALSO NOTED MOVING ACROSS PORTIONS OF THE CENTRAL PLAINS AND MISSOURI RIVER VALLEY. AT THE SURFACE A WEAK RIDGE OF HIGH BAROMETRIC PRESSURE IS NOTED ACROSS PORTIONS OF THE CENTRAL PLAINS AND MISSOURI RIVER VALLEY AND AS A RESULT...THE BOUNDARY-LAYER WIND FIELD ACROSS THE AREA REMAINS FAIRLY WEAK AND AT TIMES VARIABLE. GUIDANCE SUGGESTS THE UPPER TROPOSPHERIC SHORT WAVE...CURRENTLY CLEARING THE AREA...WILL CONTINUE MOVING EAST/SOUTHEAST THROUGH THE NEXT 24 HOURS...LIKELY CLEARING THE MISSOURI RIVER VALLEY LATER TONIGHT. QUASI-ZONAL UPPER TROPOSPHERIC FLOW IS THEN EXPECTED TO OVERTAKE THE AREA THROUGH THURSDAY...ALTHOUGH THERE ARE INDICATIONS OF ANOTHER UPPER TROPOSPHERIC SHORT WAVE CLEARING THE AREA THURSDAY INTO THURSDAY EVENING. AN OVERALL LACK IN OMEGA WOULD OTHERWISE KEEP THE AREA DRY THROUGH TONIGHT...BUT SOMEWHAT ENHANCED UPPER TROPOSPHERIC LAPSE RATES IN ASSOCIATION WITH THE PASSING SHORT WAVE TROUGH AXIS COULD BE ENOUGH TO PROMOTE WEAK SHOWER AND/OR THUNDERSTORM DEVELOPMENT ACROSS THE SOUTH/SOUTHEASTERN TWO-THIRDS OF THE CWA. THIS IS A SOLUTION SUPPORTED BY QPF FIELDS FROM THE NAM AND OPERATIONAL GFS...AND TO A LESSER EXTEND THE EC. THIS IS ALSO SUPPORTED BY SIMULATED REFLECTIVITY FROM THE HRRR AND 4KM WRF-NMM. GIVEN ALL THIS...OPTED TO GO AHEAD WITH ~20% POPS ACROSS THE SOUTH/SOUTHEASTERN TWO-THIRDS OF THE CWA UNTIL 00Z. DRY CONDITIONS ARE THEN FORECAST THROUGH THE OVERNIGHT HOURS AS DIABATIC HEATING IS LOST. GUIDANCE THEN SUGGESTS YET ANOTHER CHANCE FOR PRECIPITATION COULD BE REALIZED THURSDAY INTO THURSDAY EVENING AS THE SECOND UPPER TROPOSPHERIC SHORT WAVE CLEARS THE AREA. GIVEN THIS...WENT AHEAD WITH 20-40% POPS ACROSS MUCH OF THE CWA THURSDAY INTO THURSDAY EVENING. DESPITE FAIRLY RICH BOUNDARY-LAYER MOISTURE ACROSS THE REGION...LAPSE RATES REALLY SHOULD NOT BE ANYTHING TO WRITE HOME ABOUT AND IN FACT...GUIDANCE SUGGESTS NO MORE THAN ~500J/KG OF POTENTIAL ENERGY WILL BE AVAILABLE FOR UPDRAFT PRODUCTION THROUGH THIS EVENING. GIVEN THIS...WILL NOT INTRODUCE STRONG/SEVERE THUNDERSTORM WORDING IN THE HWO. LAPSE RATES ARE SOMEWHAT MORE RESPECTABLE THURSDAY AFTERNOON AND EVENING AND GUIDANCE RESPONDS BY PROVIDING POTENTIAL ENERGY VALUES MORE IN THE 1000-2000J/KG RANGE. IN ADDITION...DEEP-LAYER BULK SHEAR OF ~40KTS IS ALSO EXPECTED THURSDAY AFTERNOON AND EVENING AND GIVEN ALL THIS...FELT IT PRUDENT TO AT LEAST GO WITH STRONG THUNDERSTORM WORDING IN THE HWO. FINALLY...A CONTINUED WEAK BOUNDARY-LAYER WIND FIELD THROUGH THE OVERNIGHT HOURS...WORKING IN CONCERT WITH A NEAR-ZERO DEW POINT DEPRESSIONS...COULD PROMOTE AT LEAST PATCHY FOG DEVELOPMENT ACROSS MUCH OF THE AREA TONIGHT. GIVEN THIS...WENT AHEAD WITH PATCHY FOG IN THE GRIDS 06-14Z THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 406 PM CDT WED AUG 5 2015 GUIDANCE SUGGESTS QUASI-ZONAL UPPER TROPOSPHERIC FLOW WILL BE NOTED ACROSS THE REGION THROUGH MUCH OF THE LONG-TERM FORECAST PERIOD...WITH THE ONLY EXCEPTION BEING EARLY NEXT WEEK AS AN UPPER TROPOSPHERIC SHORT WAVE CLEARS THE AREA AND RIDGING STRENGTHENS OVER THE WESTERN CONUS. MULTIPLE UPPER TROPOSPHERIC PERTURBATIONS ARE ALSO EXPECTED TO CLEAR THE AREA AND AS A RESULT...POPS...GENERALLY IN THE 20-40% RANGE...REMAIN INTACT ACROSS VARIOUS PORTIONS OF THE CWA THROUGH EARLY NEXT WEEK. STRONG AND/OR SEVERE CONVECTION CERTAINLY CANNOT BE RULED OUT LATE THIS WEEK INTO EARLY NEXT WEEK...BUT AT THIS TIME IT REMAINS TOO EARLY TO TRY AND PIN DOWN TIMING OR PLACEMENT OF SUCH ACTIVITY. LITTLE CHANGE IN THE BOUNDARY-LAYER AIR MASS SHOULD PROVIDE SIMILAR TEMPERATURE READINGS FROM DAY TO DAY DURING THE LONG-TERM FORECAST PERIOD...WITH HIGHS GENERALLY IN THE 80S AND LOWS IN THE 60S. && .AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 658 PM CDT WED AUG 5 2015 VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH MOST OF THE PERIOD. PATCHY MVFR VSBY POSSIBLE TOWARD MORNING AS LIGHT WINDS DEVELOP OVERNIGHT WITH ABUNDANT BOUNDARY LAYER MOISTURE ACROSS THE AREA. CLOUDS INCREASE AFTER 12Z AS A SURFACE TROUGH APPROACHES CENTRAL NEBRASKA WITH UPPER LEVEL WAVE MOVING INTO THE NORTHERN PLAINS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...BRYANT LONG TERM...BRYANT AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
359 PM CDT TUE AUG 4 2015 .SYNOPSIS... ISSUED AT 359 PM CDT TUE AUG 4 2015 AT 20Z THE SYNOPTIC PATTERN WAS HIGHLIGHTED BY UPPER LEVEL LOWS CENTERED OVER JAMES BAY IN SOUTHEAST CANADA AND ALONG WEST COAST OF BRITISH COLUMBIA. AN UPPER LEVEL RIDGE WAS ESTABLISHED IN BETWEEN THESE TWO FEATURES. A ROBUST MID-LEVEL SHORTWAVE SLOWLY TRACKING BENEATH THE RIDGE THROUGH CENTRAL WYOMING HAS BEEN THE MAIN PLAYER IMPACTING THE SENSIBLE WEATHER OVER THE CWA FOR MUCH OF THE DAY. AT THE SURFACE...AN AREA OF LOW PRESSURE WAS CENTERED IN THE EASTERN NEBRASKA PANHANDLE...WITH A DRYLINE EXTENDING SOUTH INTO EASTERN CO...A STATIONARY TROUGH EXTENDING NORTHWARD TOWARD THE BLACK HILLS...AND A WARM FRONT DRAPED SOUTHEAST ACROSS FAR SOUTHWEST NEB INTO NORTHERN KANSAS. NORTH OF THE WARM FRONT SURFACE WINDS HAVE HAD AN EASTERLY UPSLOPE COMPONENT FOR MOST OF THE DAY...ADVECTING RICH LOW LEVEL MOISTURE INTO WESTERN NEBRASKA WITH DEWPOINTS IN THE MID TO UPPER 60S. SHOWER AND THUNDERSTORM ACTIVITY HAS BEEN ONGOING NORTH OF THE FRONT FOR MUCH OF THE DAY...MAINLY IN SOUTHWEST NEBRASKA. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 359 PM CDT TUE AUG 4 2015 DEEP CONVECTION AND CLOUD COVER THROUGH THE DAY HAS MUDDLED THE FORECAST PICTURE. HI-RES MODELS THIS MORNING ADVERTISED A NORTHERLY PROGRESSION OF THE WARM FRONT TOWARD I-80. HOWEVER CLOUD COVER AND COLD OUTFLOW FROM PERSISTENT THUNDERSTORM ACTIVITY IN SOUTHWEST NEBRASKA HAS HAMPERED THIS NORTHWARD ADVANCEMENT OF THE FRONT...AND IT HAS REMAINED STALLED NEAR THE KANSAS BORDER FOR MOST OF THE DAY. THIS WILL KEEP THE BEST INSTABILITY AND THE MAIN THREAT AREA FOR SEVERE WEATHER GENERALLY SOUTH OF THE CWA THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING. WARM AIR ADVECTION ASSOCIATED WITH A STRONG LOW VEERING WIND PROFILE NORTH OF THE SURFACE WARM FRONT WILL KEEP SCATTERED TO WIDESPREAD THUNDERSTORM CHANCES GOING ACROSS THE CWA INTO THE EVENING HOURS...WITH THE BEST CHANCES FROM SOUTHWEST INTO CENTRAL NEBRASKA. ADDITIONAL DEVELOPMENT IS POSSIBLE LATER THIS AFTERNOON IN THE VICINITY OF AN OUTFLOW BOUNDARY STALLED OVER NORTH CENTRAL NEBRASKA WHERE MESOANALYSIS INDICATES INCREASING MOISTURE LOW LEVEL CONVERGENCE...WITH THE HRRR MODEL RECENTLY PICKING UP ON THIS IDEA AS WELL. STEERING FLOW ALOFT IS RATHER WEAK...SO SLOW STORM MOTIONS WILL PROMOTE A THREAT FOR LOCALLY HEAVY RAINFALL GIVEN PWATS AOA 1.5". PRECIP CHANCES BEGIN TO END FROM WEST TO EAST OVERNIGHT AS MID- LEVEL SHORTWAVE TROUGH SLOWLY KICKS EAST AND THE INSTABILITY WANES WITH THE WEAKENING WAA REGIME JUST OFF THE SURFACE. LOW LEVEL MOISTURE HANGS AROUND AS MAIN AREA OF LOW PRESSURE REMAINS JUST OFF TO OUR WEST...WHICH KEEP LIGHT SOUTHEASTERLY WINDS AND DEWPOINTS IN THE MID TO UPPER 60S IN PLACE. BOTH THE NAM/GFS SHOW THE DEVELOPMENT OF FOG/STRATUS IN SOUTHWEST NEBRASKA LATE IN THE OVERNIGHT INTO WEDNESDAY MORNING. POPS PUSH EAST OF THE AREA BY NOON WEDNESDAY AND CLEARING SKIES PROGRESS EASTWARD. THIS WILL LEAD TO HIGH TEMPERATURES RANGING FROM THE MID 80S IN NORTH CENTRAL NEBRASKA WHERE SOME CLOUD COVER WILL HANG AROUND INTO THE AFTERNOON HOURS...TO THE LOW 90S IN SOUTHWEST NEBRASKA WHERE MORE SUNSHINE IS EXPECTED. LATEST NAM/EC GUIDANCE HAVE TRENDED COOLER FOR TOMORROW AND KEEPS MORE CLOUD COVER AROUND...SO THIS TREND WILL NEED TO MONITORED INTO TONIGHT. HAVE BEEN HESITANT TO MAKE LARGE ADJUSTMENTS TO THE FORECAST GIVEN THE AMOUNT OF CONVECTION THAT NEEDS TO PLAY OUT IN THE NEAR TERM. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 359 PM CDT TUE AUG 4 2015 A TROUGH WILL MOVE ACROSS SOUTHWESTERN CANADA WED NIGHT AND SUPPRESS THE RIDGE TO THE SOUTHERN ROCKIES. AS A RESULT THE FLOW ACROSS THE HIGH PLAINS WILL BECOME MORE ZONAL. THE TROUGH MOVES ACROSS SOUTH CENTRAL CANADA TO END THE WEEK. AS THE TROUGH SLIDES EAST THE SOUTHERN RIDGE WILL BUILD SLIGHTLY INTO THE CENTRAL ROCKIES. OVER THE WEEKEND INTO NEXT WEEK AN UPPER LEVEL LOW WILL SLOWLY PUSH TOWARDS THE PACIFIC NORTHWEST. THIS WILL CAUSE THE RIDGE TO AMPLIFLY OVER THE ROCKIES. LITTLE CHANGE TO THE ACTIVE WEATHER PATTERN. AS WE SHIFT FROM NORTHWEST FLOW TO MORE ZONAL AND BACK...THE TRAIN OF SHORT WAVES WILL CONTINUE TO PUSH ACROSS THE PLAINS. THUS THE FORECAST WILL CONTINUE TO HAVE POPS IN NEARLY EVERY PERIOD...HOWEVER DO NOT EXPECT A WASH OF A FORECAST. AS THE WAVES MOVE ACROSS A CHANCE FOR STORMS WILL EXIST...ESPECIALLY FOR THE AFTERNOON NOON INTO THE LATE EVENING HOURS. AS FOR TEMPERATURES...SEASONAL IS THE BEST WAY TO EXPLAIN. IF SHOWERS ARE OCCURING DURING THE PEAK HEAT...TEMPS MAY HOLD IN THE LOWER TO MID 80S...OTHERWISE MID 80S TO LOWER 90S WILL BE COMMON. LOWS GENERALLY IN THE 60S WITH A FEW LOCALLY COMMON COOL SPOTS TO SEE A FEW LOWS DIP INTO THE UPPER 50S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1234 PM CDT TUE AUG 4 2015 PRIMARY CONCERNS THROUGH THE CURRENT TAF PERIOD FOCUS ON TSRA ACROSS WESTERN NEBRASKA TODAY AND THIS EVENING...THEN THE POTENTIAL FOR IFR OR LOWER CIGS/VISBYS OVERNIGHT AND INTO EARLY WEDNESDAY MORNING. AS OF 1730Z THE MOST WIDESPREAD THUNDERSTORM ACTIVITY RESIDES IN SOUTHWEST NEBRASKA...WHERE LOCALIZED HEAVY RAINFALL MAY REDUCE VISBYS TO LESS THAN 3SM AT TIMES. OCCASIONAL THUNDERSTORMS WILL CONTINUE ACROSS SOUTHWEST NEBRASKA...INCLUDING THE KLBF TERMINAL...THROUGH THE AFTERNOON AND INTO THE EVENING. GUSTY ERRATIC WINDS AND HAIL WILL BE POSSIBLE WITH THE MORE INTENSE STORMS. FURTHER NORTH...LESS WIDESPREAD TSRA ACTIVITY IS EXPECTED. HAVE INCLUDED A TEMPO GROUP IN THE KVTN TAF TO HIGHLIGHT THE MOST LIKELY TIMING....GENERALLY LATE AFTERNOON/EARLY EVENING. ATTENTION TONIGHT TURNS TO THE POTENTIAL FOR LOW CIGS/VISBYS. FORECASTER CONFIDENCE IS HIGHEST ACROSS SOUTHWEST NEBRASKA...AND IFR CIGS/VISBYS HAVE BEEN INTRODUCED INTO THE TAF AT KLBF. CONDITIONS SHOULD BEGIN TO IMPROVE BY MID-MORNING WEDNESDAY. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MARTIN SHORT TERM...MARTIN LONG TERM...MASEK AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
352 AM CDT TUE AUG 4 2015 .SYNOPSIS... ISSUED AT 348 AM CDT TUE AUG 4 2015 LARGE UPPER LOWS OVER BRITISH COLUMBIA AND HUDSON BAY WITH RIDGE THROUGH NORTHERN ROCKIES INTO CANADA. VERY PRONOUNCED NEGATIVELY TILTED UPPER WAVE MOVING ACROSS WESTERN WYOMING AS SEEN IN IR... MOVING UNDER THE RIDGE. BROAD TROUGH OVER THE EASTERN CONUS FROM HUDSON BAY LOW INTO THE SOUTHEAST CONUS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 348 AM CDT TUE AUG 4 2015 MAIN PLAYER TODAY WILL BE UPPER LEVEL WAVE OVER WYOMING AND COLORADO. ONGOING CONVECTION OVER NORTH CENTRAL ZONES WILL CONTINUE THROUGH THE DAY TODAY. AS THE UPPER LOW CONTINUES TO MOVE SLOWLY EAST NORTHEAST TODAY CONVECTION WILL BEGIN OVER SOUTHWEST NEBRASKA AND THE SOUTHEAST NEBRASKA PANHANDLE ALONG STATIONARY BOUNDARY. PWATS ABOVE AN INCH OVER THE CENTRAL AND NORTHERN PLAINS ABOUT 125% OF NORMAL. AS LOW MOVES CLOSER AND HEATING OF THE DAY. FAVORABLE WIND PROFILES FOR DEVELOPMENT OF OGRANIZED CONVECTION ALONG THE STATIONARY FRONT LATE MORNING EARLY AFTERNOON. SYSTEM CLOSES OFF AND NEGATIVE TILT OF SYSTEM WILL BRING PROLONGED SLOW MOVING SYSTEM. HIGHS TODAY IN THE MID 80S. ONGOING PRICIPITATION OVER THE EAST TONIGHT WITH TEMPERATURES FALLING INTO THE UPPER 50S WEST AND LOWER 60S EAST. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 348 AM CDT TUE AUG 4 2015 SHORTWAVE RIDGING ALOFT WILL OVERSPREAD THE REGION WEDNESDAY IN THE WAKE OF TUESDAY/TUESDAY NIGHTS UPPER LEVEL DISTURBANCE. WITH THE RISING HEIGHTS ALOFT AND LITTLE FOCUS FOR CONVECTION AT THE SURFACE...WILL GO WITH A DRY DAY AFTER ANY EARLY MORNING LINGERING SHOWERS/TSTMS FROM DEPARTING UPPER LEVEL DISTURBANCE. WEDNESDAY NIGHT INTO THURSDAY...THE NEXT WAVE ALOFT MOVES ACROSS THE DAKOTAS. APPEARS TO BE JUST ENOUGH UPPER LEVEL FORCING ASSOCIATED WITH THE WAVE TO CONTINUE THE MENTION OF A FEW TSTMS ACROSS NORTH CENTRAL NEBRASKA WEDNESDAY NIGHT. THE UPPER WAVE WILL DRIVE A COLD FRONT SOUTHEAST THROUGH THE AREA THURSDAY. THE GFS AND NAM ARE IN GOOD AGREEMENT AND HAVE THE FRONT FROM ALONG A LINE FROM ROUGHLY EWING TO BURWELL TO BROKEN BOW BY AROUND 4PM OR PEAK HEATING. VERY UNSTABLE AHEAD OF THE BOUNDARY WITH SFC BASED CAPE NEAR 4500 J/KG AND 30 TO 40 KTS OF 0 TO 6 KM BULK SHEAR. IF STORMS DEVELOP SEVERE WILL BE QUITE POSSIBLE. IT DOES APPEAR STORMS WILL DEVELOP AS TEMPERATURES COOL ALOFT DURING THE AFTERNOON AND FORCING INCREASES. FRIDAY INTO THE WEEKEND...OVERALL UPPER PATTERN REMAINS LARGELY UNCHANGED WITH UPPER LEVEL HIGH TO REMAIN ANCHORED ACROSS THE SOUTHERN PLAINS. SEVERAL DISTURBANCES ALOFT WILL ROTATE EAST ACROSS THE REGION ON THE NORTHERN PERIPHERY OF THE RIDGE...WITH ISOLATED TO SCATTERED MAINLY AFTERNOON AND NIGHTIME TSTMS. TEMPERATURES WILL CONTINUE TO AVERAGE NEAR NORMAL WITH HIGHS MID TO UPPER 80S AND LOWS IN THE 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1131 PM CDT MON AUG 3 2015 THE SATELLITE AND THE RAP SUGGEST A DISTURBANCE ACROSS NCNTL COLO COULD BEGIN AFFECTING SWRN NEB TUESDAY MORNING. SCATTERED SHOWERS AND THUNDERSTORMS COULD BE UNDERWAY BY 15Z. THIS ACTIVITY SHOULD SPREAD SLOWLY EAST AND NORTHEAST THROUGHOUT THE AFTN AND EVENING. MEANWHILE...STRATUS IS BEGINNING TO DEVELOP IN CUSTER COUNTY. THE SREF INDICATES MVFR/IFR CIGS SHOULD DEVELOP BY 09Z ACROSS NCNTL NEB AND THE CNTL SANDHILLS...AND BECOME MORE NUMEROUS BY 12Z BEFORE LIFTING TO VFR AROUND 15Z TUESDAY MORNING. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...POWER SHORT TERM...POWER LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1132 PM CDT MON AUG 3 2015 .SYNOPSIS... ISSUED AT 345 PM CDT MON AUG 3 2015 STALLED SFC BOUNDARY NEAR THE NEB/KS BORDER THEN NW ALONG THE FRONT RANGE HAS STARTED TO LIFT TO THE NORTH AS A WARM FRONT. MEANWHILE UPPER LEVEL RIDGE ACROSS THE WESTERN CONUS. A MID LEVEL TROUGH IS MOVING ACROSS THE CENTRAL ROCKIES PRODUCING NUMEROUS THUNDERSTORMS ACROSS THE ROCKIES. FRONT HAS BEEN SLOW TO MOVE NORTH LEAVING TEMPERATURES SO FAR IN THE 80S ACROSS THE CWA. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 345 PM CDT MON AUG 3 2015 WARM FRONT SHOULD CONTINUE TO SLOWLY LIFT NORTHWARD AS THE MID LEVEL DISTURBANCE RIDES FROM THE CENTRAL ROCKIES ONTO THE HIGH PLAINS...INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS. SEVERE WEATHER STILL AN UNCERTAINTY. SHEAR IS MARGINAL HOWEVER INSTABILITY /CAPE/ IS GOOD. THE LAST FEW DAYS WITH STORMS A FEW HAVE BECOME STRONG AND EVEN SOME SEVERE STORMS HAVE MATERIALIZED WITH SIMILAR CONDITIONS. THE ONLY MAIN DIFFERENCE TODAY HAS BEEN TEMPS...WHICH ARE COOLER DUE TO THE HIGH CLOUDS. THUS CONFIDENCE IS HIGH FOR STORMS BUT UNSURE ON THE SEVERE POTENTIAL...BUT AGREE WITH THE MARGINAL OUTLOOK FOR SEVERE FOR NOW. CLOUDS/SHOWERS SHOULD KEEP TEMPS FOR MOST AREAS IN THE LOWER 60S. TOMORROW THE FRONT STALLS ACROSS THE AREA AND WILL BE THE FOCUS FOR CONTINUED CHANCES FOR STORMS. CLOUDS AND SHOWERS SHOULD KEEP TEMPS DOWN...IN THE LOWER TO MID 80S...HOWEVER WHEN SHOWERS ARE ONGOING TEMPS MAY FALL INTO THE 70S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 345 PM CDT MON AUG 3 2015 SCATTERED THUNDERSTORMS WILL MOVE OUT OF CENTRAL NEBRASKA BY 12Z WEDNESDAY...BUT NORTHWEST FLOW ALOFT CONTINUES AS DOES THE QUASI- STATIONARY BOUNDARY. THOUGH WARM AIR CONTINUES OVER NEBRASKA... PERSISTENT CLOUDS SHOULD HOLD THE HIGH TEMPERATURES AROUND 90. WITH THE PERSISTENT NORTHWEST FLOW ALOFT...THE PATTERN WILL REMAIN FAIRLY ACTIVE. SOUTH FLOW ON THE HIGH PLAINS BRINGS A RETURN OF SOME MOISTURE TO WESTERN NEBRASKA. CONVERGENCE IN THE THETA-E GRADIENT IS LIKELY TO INITIATE SOME CONVECTION AGAIN. THE STORMS WILL THEN SPREAD INTO THE WESTERN SANDHILLS AND CONTINUE INTO THURSDAY MORNING. THURSDAY AFTERNOON AND EVENING...THE DRY LINE (INDICATED IN THE THETA-E GRADIENT)SURGES EASTWARD INTO THE SANDHILLS. THE AVAILABLE ENERGY IS EXPECTED TO BE LESS THAN 1000J/KG WITH 35-45KT DEEP SHEAR...SO IT WILL BE DIFFICULT TO SUSTAIN THE UPDRAFTS AND THE RISK OF SEVERE THUNDERSTORMS WILL BE LOW. IT IS NOT UNTIL SATURDAY THAT THE AVAILABLE ENERGY AND THE SHEAR BECOME FAVORABLE FOR SEVERE THUNDERSTORMS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1131 PM CDT MON AUG 3 2015 THE SATELLITE AND THE RAP SUGGEST A DISTURBANCE ACROSS NCNTL COLO COULD BEGIN AFFECTING SWRN NEB TUESDAY MORNING. SCATTERED SHOWERS AND THUNDERSTORMS COULD BE UNDERWAY BY 15Z. THIS ACTIVITY SHOULD SPREAD SLOWLY EAST AND NORTHEAST THROUGHOUT THE AFTN AND EVENING. MEANWHILE...STRATUS IS BEGINNING TO DEVELOP IN CUSTER COUNTY. THE SREF INDICATES MVFR/IFR CIGS SHOULD DEVELOP BY 09Z ACROSS NCNTL NEB AND THE CNTL SANDHILLS...AND BECOME MORE NUMEROUS BY 12Z BEFORE LIFTING TO VFR AROUND 15Z TUESDAY MORNING. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MASEK SHORT TERM...MASEK LONG TERM...SPRINGER AVIATION...CDC
AREA FORECAST DISCUSSION
NWS ELKO NV
747 AM PDT TUE AUG 4 2015 .SYNOPSIS...SCATTERED THUNDERSTORMS WILL DEVELOP OVER NORTHEAST NEVADA THIS AFTERNOON...MAINLY OVER ELKO COUNTY. A PASSING DISTURBANCE WILL BRING STRONG GUSTY WEST WINDS ON WEDNESDAY. AN APPROACHING LOW PRESSURE SYSTEM FROM THE PACIFIC WILL INCREASE WINDS AND THUNDERSTORM COVERAGE FRIDAY AND SATURDAY. && .UPDATE...UPDATED ALL GRIDS THROUGH THIS EVENING, TO ALIGN WITH 12Z NAM/HRRR/06Z GFS SOLUTIONS DEPICTING CONVECTION OVER MAINLY ELKO COUNTY THIS AFTERNOON AND EVENING. HIGHEST COVERAGE EXPECTED ON/NEAR THE RUBY, INDEPENDENCE, AND JARBIDGE MTNS, BUT EXPANDED ISOLATED THUNDERSTORM WORDING ACROSS MOST OF NORTHERN NEVADA. BAT && .PREV DISCUSSION... /ISSUED AT 308 AM / SYNOPSIS...EXPECT A DRYING TREND THIS WEEK. MONSOON MOISTURE IS PUSHED OFF TO THE EAST...AND A BATCH OF PACIFIC MOISTURE IS EXPECTED LATER THIS WEEK. TEMPERATURES WILL BE NEAR NORMAL. SHORT TERM...TODAY THROUGH WEDNESDAY. THE PWS ARE BEGINNING TO DRY UP...ALTHOUGH THERE WILL BE ENOUGH REMNANT MOISTURE TO SUSTAIN CONVECTION. THE HRRR PLACES THE BULK OF THE QPF OVER NORTHERN AND EASTERN WHITE PINE...AND SOUTHERN ELKO COUNTIES...WHICH IS SECONDED BY THE NAM. AFTER TODAY...EXPECT THE UPPER LEVEL HEIGHTS TO BUILD...AND THE SURFACE TEMPERATURES TO GET NUDGED UPWARD. BY WEDNESDAY...A SLICE OF PACIFIC ENERGY WILL MOVE INTO NORTHERN CA ...ERODING THE HEIGHTS OVER THE LKN CWA...AND USHERING IN THE NEXT WAVE OF UNSTABLE CONDITIONS. LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY. THE PERIOD WILL START WITH HIGH PRESSURE EXPANDING OVER THE GREAT BASIN TO BRING A BRIEF DRY SPELL. HOWEVER A PACIFIC LOW PRESSURE SYSTEM WILL MOVE THROUGH CENTRAL CALIFORNIA AND NEVADA OVER THE WEEKEND TO INTRODUCE SOME MORE SHOWERY WEATHER TO NORTHERN AND CENTRAL NEVADA. WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. THIS WILL BE A DRY PERIOD FOR THE MOST PART AS HIGH PRESSURE CENTERED SOUTHEAST OF THE 4 CORNERS AREA OF THE COUNTRY MAINTAINS CONTROL OVER GREAT BASIN WEATHER. THE GFS MODEL IS THE OUTLIER...ADVANCING LEADING EDGE MOISTURE QUICKER...HINTING AT SOME PRECIPITATION SPREADING OUT AHEAD OF THE PACIFIC LOW STILL OFFSHORE AT THIS JUNCTURE. FRIDAY THROUGH SATURDAY NIGHT. THIS WILL BE AN UNSETTLED PERIOD. THE UPPER LOW WILL MOVE FROM THE CALIFORNIA COAST ON FRIDAY MORNING...THROUGH NEVADA...THEN EXIT NORTHWEST NEVADA SATURDAY EVENING. AS THE SOUTHWEST FLOW STRENGTHENS...BREEZY CONDITIONS ARE EXPECTED ACROSS CENTRAL NEVADA FRIDAY AFTERNOON AND EVENING. WIND GUSTS ACROSS HIGH ELEVATIONS COULD EXCEED 50 MPH...PERHAPS EVEN ALONG SOME OF THE HIGHER PASSES. THERE COULD BE SOME FIRE WEATHER CONCERNS FRIDAY AFTERNOON SOUTH OF HIGHWAY 50 AS THE WINDS INCREASE AND THE HUMIDITY LEVELS DROP BEFORE ANY MOISTURE HITS THE GROUND. SHOWERS AND THUNDERSTORMS CAN BE EXPECTED MOST EVERYWHERE FRIDAY THROUGH FRIDAY EVENING...THEN FOCUS MORE TOWARD THE NORTH AS THE LOW SKIPS THROUGH THE STATE SATURDAY AS AN OPEN WAVE. STABILIZATION SHOULD OCCUR RATHER RAPIDLY SATURDAY EVENING...ALTHOUGH A FEW SHOWERS MAY LINGER PAST MIDNIGHT NEAR THE IDAHO AND OREGON BORDERS. SUNDAY THROUGH MONDAY. HIGH PRESSURE WILL ONCE AGAIN REBUILD...CENTERED SOUTHEAST OF THE 4 CORNERS AREA TO PROVIDE ANOTHER DRY SPELL. AVIATION...THUNDERSTORMS WILL REDEVELOP ACROSS NORTHERN NEVADA TODAY...POSSIBLY AFFECTING KWMC AND KEKO. LIGHT SHOWER ACTIVITY IS EXPECTED TO LINGER ACROSS NORTHERN NEVADA THROUGH THE NIGHT. HOWEVER VFR CONDITIONS CAN BE EXPECTED FOR KWMC KEKO KELY AND KTPH THROUGH WEDNESDAY MORNING. FIRE WEATHER...REMNANTS OF MONSOON MOISTURE WILL INFLUENCE THE THUNDERSTORM ACTIVITY TODAY. AND THEN A PACIFIC SYSTEM WILL IMPACT THE WESTERN GREAT BASIN WEDNESDAY AFTERNOON. A DIALOG HAS BEGUN ABOUT THE EVOLVING SITUATION FOR FRIDAY...WHEN THERE APPEARS TO BE A GLIMMER OF A RED FLAG EVENT. DID NOT ISSUE A WATCH THIS PACKAGE...MAINLY DUE TO THE VAGARIES OF THE MODELS THE PAST SEVERAL DAYS. THE NCEP RMOP IS NOT IN CONFIDENT TERRITORY THE NEXT 96 HRS...SO THE MODELING ISSUES ARE VERY PRESENT. && .LKN WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99
AREA FORECAST DISCUSSION
NWS ELKO NV
308 AM PDT TUE AUG 4 2015 .SYNOPSIS...EXPECT A DRYING TREND THIS WEEK. MONSOON MOISTURE IS PUSHED OFF TO THE EAST...AND A BATCH OF PACIFIC MOISTURE IS EXPECTED LATER THIS WEEK. TEMPERATURES WILL BE NEAR NORMAL. && .SHORT TERM...TODAY THROUGH WEDNESDAY. THE PWS ARE BEGINNING TO DRY UP...ALTHOUGH THERE WILL BE ENOUGH REMNANT MOISTURE TO SUSTAIN CONVECTION. THE HRRR PLACES THE BULK OF THE QPF OVER NORTHERN AND EASTERN WHITE PINE...AND SOUTHERN ELKO COUNTIES...WHICH IS SECONDED BY THE NAM. AFTER TODAY...EXPECT THE UPPER LEVEL HEIGHTS TO BUILD...AND THE SURFACE TEMPERATURES TO GET NUDGED UPWARD. BY WEDNESDAY...A SLICE OF PACIFIC ENERGY WILL MOVE INTO NORTHERN CA ...ERODING THE HEIGHTS OVER THE LKN CWA...AND USHERING IN THE NEXT WAVE OF UNSTABLE CONDITIONS. .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY. THE PERIOD WILL START WITH HIGH PRESSURE EXPANDING OVER THE GREAT BASIN TO BRING A BRIEF DRY SPELL. HOWEVER A PACIFIC LOW PRESSURE SYSTEM WILL MOVE THROUGH CENTRAL CALIFORNIA AND NEVADA OVER THE WEEKEND TO INTRODUCE SOME MORE SHOWERY WEATHER TO NORTHERN AND CENTRAL NEVADA. WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. THIS WILL BE A DRY PERIOD FOR THE MOST PART AS HIGH PRESSURE CENTERED SOUTHEAST OF THE 4 CORNERS AREA OF THE COUNTRY MAINTAINS CONTROL OVER GREAT BASIN WEATHER. THE GFS MODEL IS THE OUTLIER...ADVANCING LEADING EDGE MOISTURE QUICKER...HINTING AT SOME PRECIPITATION SPREADING OUT AHEAD OF THE PACIFIC LOW STILL OFFSHORE AT THIS JUNCTURE. FRIDAY THROUGH SATURDAY NIGHT. THIS WILL BE AN UNSETTLED PERIOD. THE UPPER LOW WILL MOVE FROM THE CALIFORNIA COAST ON FRIDAY MORNING...THROUGH NEVADA...THEN EXIT NORTHWEST NEVADA SATURDAY EVENING. AS THE SOUTHWEST FLOW STRENGTHENS...BREEZY CONDITIONS ARE EXPECTED ACROSS CENTRAL NEVADA FRIDAY AFTERNOON AND EVENING. WIND GUSTS ACROSS HIGH ELEVATIONS COULD EXCEED 50 MPH...PERHAPS EVEN ALONG SOME OF THE HIGHER PASSES. THERE COULD BE SOME FIRE WEATHER CONCERNS FRIDAY AFTERNOON SOUTH OF HIGHWAY 50 AS THE WINDS INCREASE AND THE HUMIDITY LEVELS DROP BEFORE ANY MOISTURE HITS THE GROUND. SHOWERS AND THUNDERSTORMS CAN BE EXPECTED MOST EVERYWHERE FRIDAY THROUGH FRIDAY EVENING...THEN FOCUS MORE TOWARD THE NORTH AS THE LOW SKIPS THROUGH THE STATE SATURDAY AS AN OPEN WAVE. STABILIZATION SHOULD OCCUR RATHER RAPIDLY SATURDAY EVENING...ALTHOUGH A FEW SHOWERS MAY LINGER PAST MIDNIGHT NEAR THE IDAHO AND OREGON BORDERS. SUNDAY THROUGH MONDAY. HIGH PRESSURE WILL ONCE AGAIN REBUILD...CENTERED SOUTHEAST OF THE 4 CORNERS AREA TO PROVIDE ANOTHER DRY SPELL. && .AVIATION...THUNDERSTORMS WILL REDEVELOP ACROSS NORTHERN NEVADA TODAY...POSSIBLY AFFECTING KWMC AND KEKO. LIGHT SHOWER ACTIVITY IS EXPECTED TO LINGER ACROSS NORTHERN NEVADA THROUGH THE NIGHT. HOWEVER VFR CONDITIONS CAN BE EXPECTED FOR KWMC KEKO KELY AND KTPH THROUGH WEDNESDAY MORNING. && .FIRE WEATHER...REMNANTS OF MONSOON MOISTURE WILL INFLUENCE THE THUNDERSTORM ACTIVITY TODAY. AND THEN A PACIFIC SYSTEM WILL IMPACT THE WESTERN GREAT BASIN WEDNESDAY AFTERNOON. A DIALOG HAS BEGUN ABOUT THE EVOLVING SITUATION FOR FRIDAY...WHEN THERE APPEARS TO BE A GLIMMER OF A RED FLAG EVENT. DID NOT ISSUE A WATCH THIS PACKAGE...MAINLY DUE TO THE VAGARIES OF THE MODELS THE PAST SEVERAL DAYS. THE NCEP RMOP IS NOT IN CONFIDENT TERRITORY THE NEXT 96 HRS...SO THE MODELING ISSUES ARE VERY PRESENT. && .LKN WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 97/92/92/97
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1152 PM MDT MON AUG 3 2015 .AVIATION... 06Z TAF CYCLE MESOSCALE MODELS TRACK THE CLUSTER OF TS OVER NE NM GRADUALLY SEWD INTO THE TX PANHANDLE BY 10Z OR SO. WATCH FOR GUSTY OUTFLOW WINDS TO IMPACT KTCC AND POSSIBLY KLVS OUT OF THE N OR NE UNTIL 9 OR 10Z. DRY AIR WILL BE ENTRENCHED OVER THE FORECAST AREA ON TUESDAY...BUT A TROUGH PASSING N OF NM SHOULD ENHANCE INSTABILITY ENOUGH FOR ISOLD AFTN -TS/-SHRA OVER THE MTS AND ESPECIALLY THE N MTS. SOME OF THESE MAY TRACK SEWD OVER KSAF AND KLVS IN THE AFTN...THEN FARTHER SE ONTO THE NE PLAINS DURING THE EVENING. AN FAA ADAS PROBLEM HAS RESULTED IN A LONG DURATION METAR OUTAGE AT KLVS...SO NO AMENDMENTS THERE. 44 && .PREV DISCUSSION...1001 PM MDT MON AUG 3 2015... .UPDATE... MADE A QUICK UPDATE TO THE GRIDDED POP/WEATHER AND SKY COVER FORECAST FOR THE OVERNIGHT PERIOD. CHANCES WILL SIGNIFICANTLY BE DIMINISHING SHORTLY AFTER MIDNIGHT AS THE MAIN CONVECTION TRENDS EAST ACROSS THE NE PLAINS. WATCHING A PACIFIC PLUME OF MOISTURE WITH SOME BROKEN HIGHER CLOUDS OVER NORTHERN AZ. IR SATELLITE SHOWING A LITTLE MORE CLOUDS ACROSS SE ARIZONA AND SHOULD MOVE OVER THE FOUR CORNERS AREA AFTER MIDNIGHT. DECIDED TO PUT IN A CHICKEN 10 POP FOR THAT AREA. THE LATEST HRRR SUPPORTS SOME LIGHT SHOWER CHANCES THERE. OTHERWISE...THE MAIN ACTION WOULD BE ACROSS THE FAR EAST. SIGNIFICANT MID LEVEL DRY INTRUSION FOUND OVER THE AREA. THE 0Z ABQ SOUNDING SHOWED A SIGNIFICANT DRY WEDGE STARTING AROUND 10000 FEET MSL. PRETTY IMPRESSIVE. RELOOKED AT TEMPS BUT SURFACE DEWPOINTS HAVE BEEN SLOW TO DROP. THUS CURRENT MIN T FORECAST LOOKS PRETTY SOLID. WAS ORIGINALLY THINKING SOME OF THE HIGH MTN BASINS COULD DROP INTO THE UPPER 30S. DEWPOINTS WOULD NEED TO DROP A BIT MORE FOR THAT. PERHAPS TUE NIGHT. 50 && .PREV DISCUSSION...320 PM MDT MON AUG 3 2015... .SYNOPSIS... DRY AIR WILL CONTINUE TO MOVE INTO MUCH OF CENTRAL AND NORTHERN NEW MEXICO FROM THE WEST TONIGHT AND TUESDAY. THIS DRY AIR WILL KEEP AFTERNOON AND EARLY EVENING THUNDERSTORMS CONFINED TO THE SOUTH-CENTRAL MOUNTAINS AND FAR NORTHEAST HIGHLANDS AND PLAINS TUESDAY AND WEDNESDAY. MONSOON MOISTURE WILL SLOWLY RETURN FROM THE SOUTH ON THURSDAY. AS THE MOISTURE PLUME DEEPENS FRIDAY...SCATTERED TO NUMEROUS AFTERNOON AND EVENING THUNDERSTORMS WILL RETURN TO MOST AREAS FRIDAY AND CONTINUE THROUGH THE WEEKEND. && .DISCUSSION... SINGLE DIGIT RH VALUES AT/NEAR 500 MB MAKING IT VERY DIFFICULT FOR BUILDING CUMULUS TO SURVIVE OVER THE NORTHWEST HALF OF THE AREA THIS AFTERNOON. SHOWERS AND THUNDERSTORMS HAVE BEEN CONFINED TO THE SOUTHERN MOUNTAINS AND FAR NE HIGHLANDS AND PLAINS. BOTH NAM AND GFS KEEP THE NORTHEAST AND FAR EASTERN PLAINS ACTIVE THROUGH THE EVENING HOURS BEFORE THE DRY AIR TAKES OVER. TUESDAY LOOKS LIKE THE DRIEST DAY OF THE WEEK WITH THE UPPER LEVEL DRY SLOT AND UPPER HIGH NEARLY OVERHEAD. MODELS HINTING THAT UPPER LEVEL MOISTURE ASSOCIATED WITH TROPICAL STORM GUILLERMO WILL MOVE THROUGH THE AREA WEDNESDAY...RESULTING IN MORE CLOUDS AND PERHAPS A THUNDERSTORM TO TWO MORE THAN TUESDAY. MODELS IN GOOD AGREEMENT THAT THE UPPER HIGH GETS FORCED EWD SOMEWHAT THURSDAY BY A CLOSED LOW APPROACHING CENTRAL CALIFORNIA...ALLOWING MOISTURE TO BEGIN SEEPING BACK TO THE SW MTNS. THE UPPER HIGH SHIFTS FARTHER EAST OVER THE TX PANHANDLE FRIDAY. THIS SHIFT APPEARS TO RESULT IN A FULL FLEDGED SLY MONSOON PLUME AND ABOVE AVG PWATS. SCATTERED TO PERHAPS NUMEROUS AFTERNOON AND EVENING THUNDERSTORMS RETURN TO MOST AREAS FRIDAY AND SATURDAY. GFS AND ECMWF BEGIN TO DIFFER FOR SUNDAY. GFS ELONGATES THE UPPER HIGH WWD...ALLOWING SOUTHWEST WINDS TO BRING IN DRIER AIR TO THE NORTHWEST THIRD OF THE STATE. ECMWF ON THE OTHER HAND AMPLIFIES AND SHIFTS THE HIGHER FARTHER EWD OVER THE RED RIVER VALLEY OF OK/TX...RESULTING IN A VERY CLASSIC LOOKING DEEP MONSOON PLUME SMACK DAB OVER NM. SPLIT THE DIFFERENCE BTWN THE TWO OPERATIONAL SOLUTIONS AND TOWARD THE GFS ENSEMBLE CONSENSUS. 33 && .FIRE WEATHER... DRYING OUT AND HEATING UP THROUGH THURSDAY BEFORE THUNDERSTORM COVERAGE RAMPS UP FRIDAY INTO THE WEEKEND. IMPRESSIVE DRY SLOT DOMINATING NORTHWEST NEW MEXICO WILL CONTINUE TO SLOWLY ADVANCE EASTWARD. THE LEADING EDGE OF SIGNIFICANTLY DRIER MID- LEVEL AIR EXTENDED FROM TRINIDAD CO TO ALBUQUERQUE TO SILVER CITY. WEST OF THIS LINE...SHALLOW CUMULUS CLOUDS ABOUT THE EXTENT OF CONVECTIVE DEVELOPMENT...BUT WE CANNOT COMPLETELY RULE OUT A VERY ISOLATED STORM INTO THE EARLY EVENING MAINLY NEAR NAVAJO RESERVOIR AND THE WEST-CENTRAL HIGHLANDS. MORE IMPORTANTLY...DEEPER MIXING HAS ALLOWED WEST AND NORTHWEST WINDS UP TO 20MPH TO SURFACE...ESPECIALLY THE DIVIDE REGION. DEW POINTS ALREADY TRENDING DOWNWARD AS MUCH AS 10 TO 12 DEGREES AS COMPARED TO 24 HOURS AGO. FARTHER EAST...EXPECT SOME THUNDERSTORMS TO DEVELOP ACROSS PARTS OF THE EASTERN PLAINS MAINLY NORTHEAST. A FEW OF THESE COULD BRIEFLY REACH SEVERE LEVELS. OTHERWISE...RELATIVELY QUIET FOR THE FIRST TIME IN MANY DAYS. AS PREVIOUSLY MENTIONED...NUMERICAL GUIDANCE LIKELY A BIT TOO AGGRESSIVE LOWERING DEW POINTS IN THE COMING DAYS PARTICULARLY BEFORE AND JUST AFTER PEAK MIXING PERIODS. AS WE OBSERVED DURING THE LAST DRYING EPISODE...EXPECT DEW POINTS TO RAPIDLY LOWER FOR 1-3 HOURS AROUND PEAK MIXING BEFORE REBOUNDING NEARLY AS RAPIDLY AS THE BOUNDARY LAYER DECOUPLES. EITHER WAY...MIN RH VALUES WILL TREND DOWNWARD ANOTHER 5 TO 15 PERCENT OVER TODAY AND A BIT FURTHER STILL FOR WEDNESDAY. EVAPOTRANSPIRATION EFFECTS HAVE BEEN AND WILL CONTINUE TO BE FACTORED INTO THE GRIDDED DEW POINT FORECASTS. WIDENING DIURNAL TEMPERATURE RANGES THROUGH THURSDAY OWING TO THE DRIER AIR MASS. COOLER NIGHTTIME LOWS...AND MUCH WARMER/HOTTER DAYTIME TEMPERATURES THAT WILL BE AS MUCH AS 10-12 DEGREES ABOVE NORMAL. UPPER HIGH SQUARELY OVER THE AREA MID-WEEK WILL BEGIN TO SHIFT EASTWARD BY FRIDAY. THIS WILL ALLOW MOISTURE TO RETURN IN THE DEVELOPING SOUTHERLY FLOW AND RESULT IN AN UPTICK IN STORM COVERAGE INITIALLY WC/SW PORTIONS OF THE AREA...THEN MORE OF THE REGION BY THE WEEKEND. EQUALLY IMPORTANT...DIURNAL TEMP SWINGS NARROW WITH LESS HEAT TO END THE WEEK. MODERATE HAINES VALUES TO EXPAND AREAWIDE TUESDAY...AND PREDOMINATE WEDNESDAY. HAINES INDEX VALUES OF 6 WILL DEVELOP OVER A GOOD CHUNK OF CENTRAL AND NORTHERN NEW MEXICO BY THURSDAY. VERY GOOD OR BETTER VENTILATION FOR TUESDAY...BUT VENT RATES LOWER ON WEDNESDAY FOR CENTRAL/WESTERN NEW MEXICO AS TRANSPORT WINDS WEAKEN THOUGH STILL GOOD OR BETTER FOR MAJORITY OF LOCALES. KJ && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1001 PM MDT MON AUG 3 2015 .UPDATE... MADE A QUICK UPDATE TO THE GRIDDED POP/WEATHER AND SKY COVER FORECAST FOR THE OVERNIGHT PERIOD. CHANCES WILL SIGNIFICANTLY BE DIMINISHING SHORTLY AFTER MIDNIGHT AS THE MAIN CONVECTION TRENDS EAST ACROSS THE NE PLAINS. WATCHING A PACIFIC PLUME OF MOISTURE WITH SOME BROKEN HIGHER CLOUDS OVER NORTHERN AZ. IR SATELLITE SHOWING A LITTLE MORE CLOUDS ACROSS SE ARIZONA AND SHOULD MOVE OVER THE FOUR CORNERS AREA AFTER MIDNIGHT. DECIDED TO PUT IN A CHICKEN 10 POP FOR THAT AREA. THE LATEST HRRR SUPPORTS SOME LIGHT SHOWER CHANCES THERE. OTHERWISE...THE MAIN ACTION WOULD BE ACROSS THE FAR EAST. SIGNIFICANT MID LEVEL DRY INTRUSION FOUND OVER THE AREA. THE 0Z ABQ SOUNDING SHOWED A SIGNIFICANT DRY WEDGE STARTING AROUND 10000 FEET MSL. PRETTY IMPRESSIVE. RELOOKED AT TEMPS BUT SURFACE DEWPOINTS HAVE BEEN SLOW TO DROP. THUS CURRENT MIN T FORECAST LOOKS PRETTY SOLID. WAS ORIGINALLY THINKING SOME OF THE HIGH MTN BASINS COULD DROP INTO THE UPPER 30S. DEWPOINTS WOULD NEED TO DROP A BIT MORE FOR THAT. PERHAPS TUE NIGHT. 50 && .PREV DISCUSSION...602 PM MDT MON AUG 3 2015... .AVIATION... 00Z TAF CYCLE ANY LINGERING SHOWERS AND THUNDERSTORMS THIS EVENING SHOULD BE ISOLD AND FAVOR N CENTRAL...NE AND E CENTRAL NM. AN EXCEPTION WILL BE ACROSS THE FAR NE PLAINS WHERE A LINE OF SEVERE STORMS SHOULD CONTINUE TRACKING SLOWLY SSE AND EVENTUALLY EXIT INTO THE TX PANHANDLE. DRY AIR WILL BE ENTRENCHED OVER THE FORECAST AREA ON TUESDAY...BUT A TROUGH PASSING N OF NM COULD ENHANCE INSTABILITY ENOUGH FOR A FEW ISOLD AFTN STORMS OVER THE MTS. SOME OF THESE MAY TRACK SEWD OVER THE NE PLAINS DURING THE EVENING. 44 && .PREV DISCUSSION...320 PM MDT MON AUG 3 2015... .SYNOPSIS... DRY AIR WILL CONTINUE TO MOVE INTO MUCH OF CENTRAL AND NORTHERN NEW MEXICO FROM THE WEST TONIGHT AND TUESDAY. THIS DRY AIR WILL KEEP AFTERNOON AND EARLY EVENING THUNDERSTORMS CONFINED TO THE SOUTH-CENTRAL MOUNTAINS AND FAR NORTHEAST HIGHLANDS AND PLAINS TUESDAY AND WEDNESDAY. MONSOON MOISTURE WILL SLOWLY RETURN FROM THE SOUTH ON THURSDAY. AS THE MOISTURE PLUME DEEPENS FRIDAY...SCATTERED TO NUMEROUS AFTERNOON AND EVENING THUNDERSTORMS WILL RETURN TO MOST AREAS FRIDAY AND CONTINUE THROUGH THE WEEKEND. && .DISCUSSION... SINGLE DIGIT RH VALUES AT/NEAR 500 MB MAKING IT VERY DIFFICULT FOR BUILDING CUMULUS TO SURVIVE OVER THE NORTHWEST HALF OF THE AREA THIS AFTERNOON. SHOWERS AND THUNDERSTORMS HAVE BEEN CONFINED TO THE SOUTHERN MOUNTAINS AND FAR NE HIGHLANDS AND PLAINS. BOTH NAM AND GFS KEEP THE NORTHEAST AND FAR EASTERN PLAINS ACTIVE THROUGH THE EVENING HOURS BEFORE THE DRY AIR TAKES OVER. TUESDAY LOOKS LIKE THE DRIEST DAY OF THE WEEK WITH THE UPPER LEVEL DRY SLOT AND UPPER HIGH NEARLY OVERHEAD. MODELS HINTING THAT UPPER LEVEL MOISTURE ASSOCIATED WITH TROPICAL STORM GUILLERMO WILL MOVE THROUGH THE AREA WEDNESDAY...RESULTING IN MORE CLOUDS AND PERHAPS A THUNDERSTORM TO TWO MORE THAN TUESDAY. MODELS IN GOOD AGREEMENT THAT THE UPPER HIGH GETS FORCED EWD SOMEWHAT THURSDAY BY A CLOSED LOW APPROACHING CENTRAL CALIFORNIA...ALLOWING MOISTURE TO BEGIN SEEPING BACK TO THE SW MTNS. THE UPPER HIGH SHIFTS FARTHER EAST OVER THE TX PANHANDLE FRIDAY. THIS SHIFT APPEARS TO RESULT IN A FULL FLEDGED SLY MONSOON PLUME AND ABOVE AVG PWATS. SCATTERED TO PERHAPS NUMEROUS AFTERNOON AND EVENING THUNDERSTORMS RETURN TO MOST AREAS FRIDAY AND SATURDAY. GFS AND ECMWF BEGIN TO DIFFER FOR SUNDAY. GFS ELONGATES THE UPPER HIGH WWD...ALLOWING SOUTHWEST WINDS TO BRING IN DRIER AIR TO THE NORTHWEST THIRD OF THE STATE. ECMWF ON THE OTHER HAND AMPLIFIES AND SHIFTS THE HIGHER FARTHER EWD OVER THE RED RIVER VALLEY OF OK/TX...RESULTING IN A VERY CLASSIC LOOKING DEEP MONSOON PLUME SMACK DAB OVER NM. SPLIT THE DIFFERENCE BTWN THE TWO OPERATIONAL SOLUTIONS AND TOWARD THE GFS ENSEMBLE CONSENSUS. 33 && .FIRE WEATHER... DRYING OUT AND HEATING UP THROUGH THURSDAY BEFORE THUNDERSTORM COVERAGE RAMPS UP FRIDAY INTO THE WEEKEND. IMPRESSIVE DRY SLOT DOMINATING NORTHWEST NEW MEXICO WILL CONTINUE TO SLOWLY ADVANCE EASTWARD. THE LEADING EDGE OF SIGNIFICANTLY DRIER MID- LEVEL AIR EXTENDED FROM TRINIDAD CO TO ALBUQUERQUE TO SILVER CITY. WEST OF THIS LINE...SHALLOW CUMULUS CLOUDS ABOUT THE EXTENT OF CONVECTIVE DEVELOPMENT...BUT WE CANNOT COMPLETELY RULE OUT A VERY ISOLATED STORM INTO THE EARLY EVENING MAINLY NEAR NAVAJO RESERVOIR AND THE WEST-CENTRAL HIGHLANDS. MORE IMPORTANTLY...DEEPER MIXING HAS ALLOWED WEST AND NORTHWEST WINDS UP TO 20MPH TO SURFACE...ESPECIALLY THE DIVIDE REGION. DEW POINTS ALREADY TRENDING DOWNWARD AS MUCH AS 10 TO 12 DEGREES AS COMPARED TO 24 HOURS AGO. FARTHER EAST...EXPECT SOME THUNDERSTORMS TO DEVELOP ACROSS PARTS OF THE EASTERN PLAINS MAINLY NORTHEAST. A FEW OF THESE COULD BRIEFLY REACH SEVERE LEVELS. OTHERWISE...RELATIVELY QUIET FOR THE FIRST TIME IN MANY DAYS. AS PREVIOUSLY MENTIONED...NUMERICAL GUIDANCE LIKELY A BIT TOO AGGRESSIVE LOWERING DEW POINTS IN THE COMING DAYS PARTICULARLY BEFORE AND JUST AFTER PEAK MIXING PERIODS. AS WE OBSERVED DURING THE LAST DRYING EPISODE...EXPECT DEW POINTS TO RAPIDLY LOWER FOR 1-3 HOURS AROUND PEAK MIXING BEFORE REBOUNDING NEARLY AS RAPIDLY AS THE BOUNDARY LAYER DECOUPLES. EITHER WAY...MIN RH VALUES WILL TREND DOWNWARD ANOTHER 5 TO 15 PERCENT OVER TODAY AND A BIT FURTHER STILL FOR WEDNESDAY. EVAPOTRANSPIRATION EFFECTS HAVE BEEN AND WILL CONTINUE TO BE FACTORED INTO THE GRIDDED DEW POINT FORECASTS. WIDENING DIURNAL TEMPERATURE RANGES THROUGH THURSDAY OWING TO THE DRIER AIR MASS. COOLER NIGHTTIME LOWS...AND MUCH WARMER/HOTTER DAYTIME TEMPERATURES THAT WILL BE AS MUCH AS 10-12 DEGREES ABOVE NORMAL. UPPER HIGH SQUARELY OVER THE AREA MID-WEEK WILL BEGIN TO SHIFT EASTWARD BY FRIDAY. THIS WILL ALLOW MOISTURE TO RETURN IN THE DEVELOPING SOUTHERLY FLOW AND RESULT IN AN UPTICK IN STORM COVERAGE INITIALLY WC/SW PORTIONS OF THE AREA...THEN MORE OF THE REGION BY THE WEEKEND. EQUALLY IMPORTANT...DIURNAL TEMP SWINGS NARROW WITH LESS HEAT TO END THE WEEK. MODERATE HAINES VALUES TO EXPAND AREAWIDE TUESDAY...AND PREDOMINATE WEDNESDAY. HAINES INDEX VALUES OF 6 WILL DEVELOP OVER A GOOD CHUNK OF CENTRAL AND NORTHERN NEW MEXICO BY THURSDAY. VERY GOOD OR BETTER VENTILATION FOR TUESDAY...BUT VENT RATES LOWER ON WEDNESDAY FOR CENTRAL/WESTERN NEW MEXICO AS TRANSPORT WINDS WEAKEN THOUGH STILL GOOD OR BETTER FOR MAJORITY OF LOCALES. KJ && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 50
AREA FORECAST DISCUSSION
NWS BUFFALO NY
215 AM EDT TUE AUG 4 2015 .SYNOPSIS... SOMEWHAT UNSETTLED WEATHER WILL BE FOUND ACROSS THE REGION TUESDAY AND TUESDAY EVENING IN ADVANCE OF A SECONDARY COLD FRONT THAT WILL CROSS THE REGION TUESDAY NIGHT. FOLLOWING THE PASSAGE OF THIS SECOND COLD FRONT...SOME SCATTERED SHOWERS WILL LINGER ACROSS THE NORTH COUNTRY THROUGH WEDNESDAY...OTHERWISE IT WILL TURN DRIER AND COOLER FOR THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /THROUGH TODAY/... FOR THE BALANCE OF THE NIGHT...OUR REGION SHOULD EXPERIENCE MAINLY DRY WEATHER SAVE FOR A FEW SHOWERS PASSING ACROSS LAKE ONTARIO AND INTO THE NORTH COUNTRY OUT AHEAD OF A WEAK SURFACE TROUGH... AND A LINGERING SHOWER OR TWO ACROSS INTERIOR PORTIONS OF THE SOUTHERN TIER. SOME PARTIAL CLEARING MAY ALSO ALLOW SOME PATCHY FOG TO DEVELOP...ESPECIALLY IN THE VALLEYS OF THE SOUTHERN TIER AND SOUTHEAST OF LAKE ONTARIO WHERE THE STEADIEST SHOWERS FELL ON MONDAY. OTHERWISE...TEMPERATURES WILL BE COOLER WITH OVERNIGHT LOWS RANGING FROM THE MID 50S TO LOWER 60S. A MORE SUBTLE SECONDARY BOUNDARY WILL GRADUALLY PUSH INTO THE REGION ON TUESDAY. THIS COMBINED WITH THE UPPER LEVEL TROUGH SHOULD BE ENOUGH FOR SOME SHOWERS AND POSSIBLY THUNDERSTORMS TO DEVELOP. 00Z NAM AND THE LATEST HRRR GUIDANCE SUGGEST THE MOST WIDESPREAD SHOWERS WILL BE EAST OF LAKE ONTARIO AS A SUBTLE WAVE CROSSES WITH THE FRONT. THIS WAVE WILL EXIT...BUT AS THE FRONT SAGS SOUTH AND WITH DAYTIME HEATING EXPECT ANOTHER BATCH OF STEADIER SHOWERS TO DEVELOP SOUTH OF LAKE ONTARIO ALONG THE SURFACE CONVERGENCE BOUNDARY. THIS SAID...WITH A CYCLONIC FLOW ALOFT DUE TO THE UPPER LEVEL TROUGH...IT IS DIFFICULT TO RULE OUT AT LEAST A CHANCE FOR SHOWERS AT ANY LOCATION. HIGHS WILL BE NOTABLY COOLER...ONLY IN THE LOWER TO MID 70S IN MOST AREAS. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... EVENING UPDATE...A LOBE OF UNSEASONABLY COOL -1SD TO -2SD 850MB AIR WILL SWING ACROSS THE EASTERN GREAT LAKES TUESDAY NIGHT AND WEDNESDAY. THIS WILL INCREASE LAKE INDUCED INSTABILITY LEVELS OVER LAKES ERIE AND ONTARIO WITH THE POTENTIAL FOR LAKE ENHANCED RAIN SHOWERS EMBEDDED WITHIN MORE WIDESPREAD CHANCES OF SHOWERS AHEAD OF A 500MB VORT MAX. PREVIOUS DISCUSSION...THE LONGWAVE TROUGH AXIS WILL BE CENTERED ACROSS THE LOWER GREAT LAKES AS WE MOVE INTO THE MIDWEEK...RESULTING IN A COOL AND UNSETTLED START TO THE PERIOD. THE COMBINATION OF DPVA AND COLDER AIR ALOFT ASSOCIATED WITH THE TROUGH WILL MAKE TUESDAY NIGHT AND WEDNESDAY MORNING THE MOST UNSETTLED PART OF THE PERIOD. IN FACT...WITH 850MB TEMPS FALLING TO +8C TO +10C AND CYCLONIC WESTERLY FLOW IN PLACE ACROSS THE AREA...IT IS QUITE POSSIBLE THAT WE COULD SEE THE DEVELOPMENT OF LAKE EFFECT RAIN SHOWERS DOWNSTREAM OF LAKE ERIE...AND TO A GREATER EXTENT EAST OF OF LAKE ONTARIO WHERE LONGER FETCH SHOULD COMPENSATE FOR THE LACK OF DEEP MOISTURE. AS ELUDED TO ABOVE...AREAS DOWNWIND OF LAKE ERIE WILL BE ON THE SOUTHERN FRINGE OF THE DEEPER SYNOPTIC MOISTURE...HENCE THE LOWER POPS ACROSS WESTERN NY. HOWEVER IT IS WORTH NOTING THAT A STRONG VORT MAX IS PROGGED TO BE CROSSING THE FORECAST AREA OVERNIGHT...AND THIS WILL YIELD AT LEAST A CHANCE OF SHOWERS ELSEWHERE. NONETHELESS...EVEN WHERE WE DON`T SEE LAKE EFFECT SHOWERS...WE WILL LIKELY SEE AN ABUNDANCE OF CLOUD COVER. THE COOL AIR ASSOCIATED WITH THE TROUGH WILL YIELD LOWS IN THE 50S EXCEPT FOR IMMEDIATELY ALONG THE LAKE WHERE TEMPS WILL BOTTOM OUT AROUND 60. ANY LINGERING SHOWERS SHOULD TAPER OFF WEDNESDAY MORNING AS THE MAIN VORT MAX MOVES INTO EASTERN NEW YORK AND DIURNAL HEATING DISRUPTS ANY LINGERING LAKE EFFECT SHOWERS. HOWEVER WE MAY SEE A RESURGENCE OF SHOWER ACTIVITY EAST OF LAKE ONTARIO BY WEDNESDAY AFTERNOON AS THE CORE OF THE UPPER LEVEL TROUGH WILL STILL BE OVERHEAD THE NORTH COUNTRY AND EASTERN NEW YORK WITH A DECENT AMOUNT OF DIURNAL CLOUDINESS ELSEWHERE ACROSS THE FORECAST AREA ALONG WITH SEASONABLY COOL TEMPERATURES FEATURING HIGHS IN THE LOWER 70S. THE CORE OF THE COLD AIR ALOFT WILL MOVE ACROSS THE REGION WEDNESDAY NIGHT...CAUSING TEMPERATURES TO RUN A COUPLE OF DEGREES COOLER WITH LOWS IN THE LOW TO MID 50S EXCEPT IMMEDIATELY ALONG THE LAKESHORES WHERE LOWS RUN CLOSE TO THE 60 DEGREE MARK. UNLIKE TUESDAY NIGHT...LAKE EFFECT SHOWERS ARE NOT EXPECTED TO BE AN ISSUE OWING TO INCREASINGLY DRY AIR ALOFT AND NOMINALLY STRONGER SHEAR. HOWEVER...WE MAY SEE A FEW AREAS OF LAKE-INDUCED CLOUDINESS LINGER EAST OF LAKE ONTARIO AS THE BACK EDGE OF THE TROUGH MOVES THROUGH THE AREA. CONDITIONS WILL REMAIN DRY THURSDAY AND THURSDAY NIGHT AS THE UPPER LEVEL TROUGH GIVES WAY TO ZONAL FLOW ALOFT. THE QUESTION MARK IS A STORM SYSTEM PROGGED TO CROSS THE OHIO VALLEY AND CENTRAL APPALACHIANS THURSDAY AND THURSDAY NIGHT. THIS SYSTEM MAY BRING A FEW SHOWERS TO THE SOUTHERN TIER DEPENDING ON HOW FAR NORTH IT DRIFTS...HOWEVER FOR NOW WILL MAINTAIN LOW CHANCE POPS FOR THE TIME BEING. WITH NO SIGNIFICANT TEMPERATURE ADVECTION GOING ON...TEMPERATURES WILL RUN CLOSE TO WEDNESDAY/WEDNESDAY NIGHT`S READINGS WITH HIGHS IN THE LOWER 70S AND LOWS IN THE 50S. && .LONG TERM /FRIDAY THROUGH MONDAY/... THE LONGWAVE TROUGH WILL MAINTAIN ITS POSITION OVER EASTERN CANADA THROUGH THE WEEKEND AS A SERIES OF SHORTWAVES MOVING ALONG THE U.S. CANADIAN BORDER WILL LIKELY RE-AMPLIFY THE TROUGH ACROSS THE GREAT LAKES. WHILE THERE ARE CONSIDERABLE DIFFERENCES ON THE DETAILS IN THE EVOLUTION OF THIS SCENARIO...THIS GENERAL TREND SUGGESTS THAT WE WILL SEE AT LEAST A CHANCE OF SHOWERS THIS WEEKEND WITH TEMPERATURES THAT WILL CONTINUE TO RUN ON THE COOLER SIDE OF AVERAGE. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... FOR THE REST OF THE NIGHTTIME HOURS...VFR CONDITIONS WILL CONTINUE TO PREVAIL WITH JUST A FEW LIGHT SHOWERS EXITING INTERIOR PORTIONS OF THE WESTERN SOUTHERN TIER...AND ALSO PUSHING ACROSS LAKE ONTARIO INTO THE NORTH COUNTRY. DUE TO THE LIGHT NATURE OF THE SHOWERS... THESE WILL BE UNLIKELY TO PRODUCE REDUCTIONS IN VSBY. OF MORE CONCERN WILL BE THE POTENTIAL FOR PATCHY FOG DEVELOPMENT WITHIN THE INTERIOR VALLEYS OF THE SOUTHERN TIER AND FROM PORTIONS OF THE FINGER LAKES NORTHEASTWARD INTO OSWEGO COUNTY...WHERE SOME IFR/MVFR RESTRICTIONS IN VSBY WILL BE POSSIBLE. ANY SUCH FOG THAT DEVELOPS SHOULD THEN MIX OUT FAIRLY QUICKLY EARLY TUESDAY MORNING...LEAVING BEHIND GENERAL VFR CONDITIONS THROUGH LATE MORNING/MIDDAY. AFTER THAT TIME...THE COMBINATION OF AN APPROACHING SECONDARY COLD FRONT AND DIURNAL HEATING WILL LEAD TO INCREASING CLOUD COVER AND THE DEVELOPMENT OF SCATTERED TO NUMEROUS SHOWERS AND POSSIBLE THUNDERSTORMS TUESDAY AFTERNOON AND EVENING... ANY OF WHICH COULD PRODUCE RESTRICTIONS TO IFR/MVFR. THE FRONT ITSELF WILL CROSS THE REGION TUESDAY NIGHT...WITH DRYING AND SUBSIDENCE IN ITS WAKE LEADING TO A RETURN TO DRIER WEATHER/VFR CONDITIONS IN MOST LOCATIONS OVERNIGHT...THOUGH THE SHOWERS WILL LIKELY LINGER THROUGH THE NIGHT EAST OF LAKE ONTARIO OWING TO A COMBINATION OF UPSLOPE FLOW AND INCREASING LAKE INFLUENCES. OUTLOOK... WEDNESDAY...SCATTERED SHOWERS/POSSIBLE MVFR ACROSS THE NORTH COUNTRY AND SAINT LAWRENCE VALLEY...OTHERWISE VFR. THURSDAY THROUGH MONDAY...VFR. && .MARINE... A FALL LIKE AIRMASS IN THE WAKE OF A SECOND COLD FRONT COULD SET THE STAGE FOR WATERSPOUTS ON LAKE ONTARIO TUESDAY NIGHT AND WEDNESDAY. BUFKIT SOUNDINGS SHOW STEEP CONVECTIVE CLOUD DEPTHS AND LAKE-850 DELTA-TS OF AROUND 15C WHICH FIT THE SZILAGYI WATERSPOUT NOMOGRAM POTENTIAL FOR UPPER LOW WATERSPOUTS. A SLIGHT CHANCE HAS BEEN ADDED INTO THE FORECAST OVER THE LAKES. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...JJR NEAR TERM...APFFEL/JJR SHORT TERM...SMITH/WOOD LONG TERM...WOOD AVIATION...JJR MARINE...APFFEL/JJR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
729 PM EDT WED AUG 5 2015 .SYNOPSIS...A COLD FRONT WILL SETTLE SOUTHWARD THEN STALL OUT OVER NORTH CAROLINA TONIGHT THROUGH THURSDAY. A WAVE OF LOW PRESSURE WILL TRACK EASTWARD ALONG THE FRONT LATE THURSDAY THROUGH FRIDAY... SHIFTING OFF THE COAST FRIDAY NIGHT AS THE FRONT PUSHES TO OUR SOUTH. && .NEAR TERM /THROUGH TONIGHT/... AS OF 310 PM WEDNESDAY... STILL APPEARS THAT THE VAST MAJORITY OF CENTRAL NC WILL STAY DRY THROUGH TONIGHT. THE EXCEPTIONS WILL BE ACROSS THE FAR NORTH... AND IN THE FAR SOUTHERN CWA THROUGH EARLY EVENING. THE SURFACE FRONTAL ZONE TO OUR NORTH HAS MOVED LITTLE IN RECENT HOURS... STILL STRETCHING ACROSS SRN VA INTO SE KY (ALTHOUGH PASSAGE OF NUMEROUS CONVECTIVE OUTFLOWS FURTHER WEST INTO THE MID MISS VALLEY HAS PROPELLED THE SYNOPTIC FRONT SOUTHWARD THERE). SURFACE HIGH PRESSURE CENTERED WELL TO THE NW OVER THE NRN GREAT LAKES REGION INTO WRN ONTARIO WILL SHIFT EASTWARD TONIGHT... AND THIS MORE DENSE AIR MAY BE JUST ENOUGH TO NUDGE THE FRONT SOUTHWARD INTO NRN NC... HOWEVER IT`S DIFFICULT TO DETERMINE HOW FAR SOUTH IT WILL GET. OUTSIDE OF THE FAR NRN CWA... IT`S MORE LIKELY THAT WE`LL SEE A WIND SHIFT BUT RELATIVELY LITTLE DROP IN THICKNESSES OVER MOST OF THE CWA OVERNIGHT. WEAK MID LEVEL MCV/S NOW OVER WRN KY/TN WILL CONTINUE TO MOVE EASTWARD TOWARD WRN VA/WRN NC TONIGHT... HOWEVER THESE MAY UNDERGO DEAMPLIFICATION DUE TO THE STRENGTH/INFLUENCE OF THE MID LEVEL TROUGH AXIS STRETCHING FROM SE NEB INTO NRN ARK AS IT SHIFTS TO THE ESE... EFFECTIVELY REINFORCING THE WEAK MID LEVEL RIDGING NOW OVER OUR REGION AND REDUCING OR ELIMINATING ANY TANGIBLE DYNAMIC FORCING FOR ASCENT. THE LATEST HI-RES NMM/ARW AND RECENT HRRR RUNS SUPPORT EARLIER OUTPUT FROM THE NCAR ENSEMBLE AND NSSL WRF SHOWING ISOLATED CELLS IN THE FAR SRN CWA INTO SC (AS IS OCCURRING) WITHIN THE HIGHER LOW-LEVEL LAPSE RATE NEAR A LOW LEVEL THERMAL / MOISTURE GRADIENT (NOTED IN SFC-925-850 MB RAP ANALYSES) THROUGH EARLY EVENING... AND OVER THE FAR NRN CWA NEAR THE FRONTAL ZONE... WHERE RECOVERING PW (EXPECTED TO INCH UP CLOSER TO 1.5" TONIGHT)... WEAK LOW LEVEL MASS CONVERGENCE... AND STEEPER MID LEVEL LAPSE RATES WILL PROMPT ISOLATED TO SCATTERED CONVECTION... LASTING UNTIL THE 05Z-07Z TIME FRAME... AFTER LOSS OF HEATING. WILL MAINTAIN THIS POP CONFIGURATION THROUGH TONIGHT... WITH NO MORE THAN A LOW-END CHANCE POP ANYWHERE GIVEN THE WEAK LIFT AND FOCUS. SHOULD SEE A FAIR AMOUNT OF CONVECTIVE DEBRIS CLOUDS DRIFTING OVERHEAD ESPECIALLY LATER TONIGHT... YIELDING A GENERALLY PARTLY CLOUDY SKY. LOWS FROM AROUND 68 NORTH TO 74 SOUTH. -GIH && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 320 PM WEDNESDAY... CONFIDENCE IS FAIRLY HIGH IN A TREND TO UNSETTLED WEATHER FOR THIS TIME PERIOD. THE AFOREMENTIONED SHORTWAVE TROUGH WILL CONTINUE HEADING ESE... LIKELY PRECEDED BY SEVERAL OUTFLOWS AND WEAKER WAVES THAT WILL HELP FURTHER MOISTEN THE COLUMN... STARTING WITH THE MID AND UPPER LEVELS AND EXPANDING GROUNDWARD HEADING INTO THU EVENING. MODEL CONSENSUS IS FOR INCREASING CHANCES FOR SHOWERS AND STORMS THU AFTERNOON REMAINING ELEVATED THROUGH THU NIGHT... ALTHOUGH VARIATIONS IN THE DETAILS PERSIST WITH THE NAM/SREF MEAN/ECMWF MUCH FASTER (BY ROUGHLY 6 HRS) TO SPREAD PRECIP EASTWARD ACROSS NC THAN THE GFS. GIVEN THE OVERALL STRENGTHENING OF UPPER DIVERGENCE OVER THE REGION BY 18Z-00Z AND WIDESPREAD 30-40 M HEIGHT FALLS... TEND TO FAVOR THE FASTER ARRIVAL OF HIGHER CONVECTION COVERAGE. WILL KEEP THE TREND UP TOWARD CHANCE POPS ARRIVING IN THE NW FIRST DURING THE EARLY TO MID AFTERNOON... SPREADING QUICKLY EASTWARD WITH RISING POPS TOWARD LIKELY FROM MID AFTERNOON ONWARD... KEEPING HIGH POPS THROUGH THE NIGHT AS THE MID LEVEL SHORTWAVE TROUGH AND ACCOMPANYING POTENT SURFACE LOW TRAVERSE THE AREA WITH ADDED LOW LEVEL MASS CONVERGENCE ESPECIALLY ACROSS THE NORTH. WHILE A FEW STRONGER STORMS APPEAR POSSIBLE GIVEN THE ADDED DYNAMIC FORCING FOR ASCENT AND STRENGTHENING MID LEVEL FLOW (BOTH MORE THAN WE TYPICALLY SEE IN YOUR AVERAGE EARLY AUGUST TIME PERIOD)... AN EARLIER ONSET AND CONSIDERABLE CLOUDS OUT AHEAD OF THE WAVE SHOULD SUPPRESS CAPE VALUES A BIT... KEEPING INSTABILITY MARGINAL AT MOST ESPECIALLY IN THE NORTHWEST. EXPECT HIGHS OF 87-95 (A TAD LOWER THAN GUIDANCE IN THE NW GIVEN THE LIMITED HEATING AND CLOSER TO GUIDANCE IN THE SE). LOWS 67-74. -GIH && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... AS OF 245 PM WEDNESDAY... OVERALL THE SYNOPTIC PATTERN THROUGHOUT THE LONG TERM PERIOD WILL FEATURE RIDGING OVER THE SOUTH-CENTRAL/SOUTHWEST CONUS AND TROUGHING OVER THE EAST. TO BEGIN THE LONG TERM PERIOD...MODELS HAVE SLOW THE PROGRESSION OF A SHORT WAVE TROUGH ACROSS THE AREA EARLY FRIDAY AND A SECONDARY `KICKER` WAVE LATE FRIDAY INTO SATURDAY. AS A RESULT... PRECIP CHANCES WILL BE SLOWER TO EXIT THE REGION...WITH MUCH OF THE DAY ON FRIDAY LOOKING TO HAVE DECENT PRECIP CHANCES. PRECIP CHANCES WILL DECREASE FROM WEST TO EAST DURING THE AFTERNOON/EVENING HOURS AS THE LOW FINALLY LIFTS TO THE NORTHEAST THE SURFACE FRONT IS PUSHED FURTHER TO THE SOUTH/EAST. FOR THE WEEKEND...MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE FRONT BEING PUSHED TO OUR SOUTH/EAST...AND BECOMING NEARLY STATIONARY THERE. HIGH PRESSURE WILL BUILD IN AND THIS SHOULD RESULT IN A MOSTLY DRY FORECAST...WITH ONLY SOME ISOLATED DIURNAL TYPE ACTIVITY...MOSTLY ACROSS THE SOUTH/EAST IN CLOSER PROXIMITY TO THE BOUNDARY AND MAYBE IN THE WESTERN PIEDMONT BY SUNDAY AS ACTIVITY DEVELOPING IN THE HIGHER TERRAIN MAY DRIFT INTO THAT AREA. THE HIGH WILL BEGIN TO SHIFT OFFSHORE EARLY NEXT WEEK AND THEREFORE MOISTURE/PRECIP CHANCES WILL SLOWLY BEGIN TO INCREASE. OUR NEXT FRONT IS PROGGED TO APPROACH FROM THE WEST ON TUESDAY OR WEDNESDAY BRINGING BETTER CHANCES OF PRECIP TO THE AREA ONCE AGAIN. TEMPS WILL BE BELOW NORMAL FRIDAY AND SATURDAY...BEFORE GRADUALLY MODERATING BACK UP TO NEAR/SLIGHTLY ABOVE NORMAL BY NEXT WEEK. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... AS OF 729 PM WEDNESDAY... 24-HOUR TAF PERIOD: THERE ARE CURRENTLY SOME SHOWERS AND STORMS MOVING TOWARD KINT AND KGSO...AS WELL AS A SECOND AREA NEAR KFAY. FOR NOW ALL STORMS ARE OUTSIDE THE VICINITY...HOWEVER THE TRIAD TERMINALS WILL LIKELY SEE AT LEAST SHOWERS NEAR THE TERMINALS IF NOT THUNDERSTORMS...DURING THE NEXT FEW HOURS. OTHERWISE...CIGS AND VISBYS SHOULD REMAIN VFR THROUGH TONIGHT...WITH WINDS BECOMING LIGHT AND VEERING FROM SW TO NW BEHIND THE FRONT. THE FRONT WILL LIKELY STALL OVER THE AREA OVERNIGHT...MOVING THROUGH THURSDAY AFT THROUGH FRIDAY...BRINGING WITH IT THE CHANCE FOR MORE SHOWERS AND STORMS ACROSS THE EASTERN HALF OF THE AREA (KFAY...KRDU...AND KRWI). -RAH LOOKING AHEAD: THE CHANCE FOR SUB-VFR CONDITIONS WILL CONTINUE THURSDAY NIGHT THROUGH MUCH OF FRIDAY...AS A WAVE OF LOW PRESSURE AND UPPER LEVEL DISTURBANCE TRACK ALONG THE FRONT ACROSS THE REGION...BRINGING SCATTERED TO NUMEROUS SHOWERS/STORMS. SHOWER/STORM CHANCES WILL DIMINISH FRIDAY NIGHT AS THE FRONT SETTLES SOUTH OF THE AREA...BUT SUB-VFR CIGS/VSBYS ARE LIKELY TO LINGER UNTIL SATURDAY MORNING...WHEN A HIGH PRESSURE RIDGE WILL BUILD IN FROM THE NORTH...AND PERSIST INTO MONDAY WITH MAINLY VFR CONDITIONS MID MORNING SATURDAY THROUGH MONDAY. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...KRD AVIATION...RAH/HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
100 PM EDT TUE AUG 4 2015 .SYNOPSIS...AN AREA OF LOW PRESSURE WILL TRACK FROM NEAR MYRTLE BEACH NORTHEASTWARD ALONG THE SOUTHERN OUTER BANKS OF NORTH CAROLINA THROUGH TONIGHT. MEANWHILE... A COLD FRONT WILL APPROACH FROM THE NORTHWEST AND SETTLE INTO NORTH CAROLINA ON WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 955 AM TUESDAY... FORECAST IS IN GOOD SHAPE. LATEST SURFACE ANALYSIS SHOWS SURFACE LOW PRESSURE OFF THE NRN SC COAST POISED TO MOVE TO THE NORTHEAST TODAY NEAR THE SRN NC COAST AND SRN OUTER BANKS. A RATHER IMPRESSIVE SHIELD OF CONVECTION ACCOMPANIES THIS LOW... AND SOME OF THESE ELEMENTS HAVE SPREAD NORTHWESTWARD INTO THE SE CWA. THIS BEHAVIOR IS EXPECTED TO PERSIST THROUGH TODAY... RESULTING IN SCATTERED SHOWERS AND STORMS OVER THE SOUTHEAST COASTAL PLAIN EAST OF I-95. THIS IS IN LINE WITH NEARLY ALL COARSE AND HI-RES GUIDANCE INCLUDING THE SPC SSEO... NSSL WRF... AND NCAR ENSEMBLE OUTPUT. SUBSIDENCE ON THE WEST SIDE OF THIS FORMIDABLE LOW SHOULD HELP TEMPER MUCH OF THE CONVECTION MORE INLAND (NW OF A FAY-WILSON LINE)... HOWEVER FARTHER NW OVER THE NW AND FAR NRN PIEDMONT... SHEARED VORTICITY SPREADING ESE FROM NE/IA/MO CONVECTION INTO THE BROAD BASE OF THE MEAN LONGWAVE TROUGH WILL SPREAD INTO ERN KY/TN AND WRN VA/NC LATER THIS AFTERNOON THROUGH EVENING... LIKELY INSTIGATING ISOLATED TO SCATTERED CONVECTION ALONG EITHER AN OLD OUTFLOW AND/OR THE BAGGY PIEDMONT TROUGH... ALTHOUGH AS WAS THE CASE YESTERDAY... ENTRAINMENT OF DRY AIR WITHIN THE BELOW-NORMAL-PW ENVIRONMENT PERSISTING OVER THE WRN PIEDMONT OF NC WILL LIMIT COVERAGE/STRENGTH/LIFETIME OF ANY SUCH CONVECTION. THE HRRR AND NCAR ENSEMBLE PROBABILITIES BRING THIS CONVECTION INTO OUR NW CWA AROUND MID AFTERNOON... WITH A SLOW SOUTHEASTWARD DRIFT AND EVENTUAL DISSIPATION BY MID EVENING... IN LINE WITH THE CURRENT FORECAST WITH ONLY MINOR TWEAKS NEEDED. AFOREMENTIONED SUBSIDENCE SHOULD PROMPT GOOD HEATING PARTICULARLY OVER THE SRN AND ERN PIEDMONT AND WRN SANDHILLS (AWAY FROM THE COASTAL CLOUD SHIELD)... AND HIGHS IN THE MID-UPPER 90S APPEAR ATTAINABLE THERE... WITH LOW-MID 90S ELSEWHERE... COOLEST IN THE EXTREME ESE CWA. -GIH PREVIOUS DISCUSSION FROM 335 AM: A 1011 MB SURFACE LOW CENTERED JUST SOUTH OF KCHS IS FORECAST TO TRACK NORTHEASTWARD GENERALLY ALONG THE COAST OF THE CAROLINAS THROUGH TONIGHT. DEEP CONVECTION HAS BLOSSOMED DURING THE PAST COUPLE OF HOURS IN ASSOCIATION WITH THE LOW...AND EXTRAPOLATION OF THIS ACTIVITY (AND THE TRACK OF THE SURFACE LOW) SUGGESTS IT SHOULD REMAIN CONFINED FROM SAMPSON AND WAYNE COUNTIES AND ESPECIALLY POINTS EASTWARD...IN AXIS OF FOCUSED 925-850 MB MOISTURE TRANSPORT TO THE EAST OF AN INVERTED TROUGH AXIS FROM THE LOW CENTER. OTHERWISE...A PIEDMONT TROUGH WILL SHARPEN THIS AFTERNOON...AHEAD OF A COLD FRONT THAT WAS ANALYZED THIS MORNING FROM THE LOWER GREAT LAKES TO THE LOWER OH VALLEY. THE MODELS INDICATE THE COLD FRONT WILL SETTLE SOUTH ACROSS VA TONIGHT...TO NEAR THE NC BORDER BY WED MORNING. WILL RETAIN A 20-30 PERCENT CHANCE OF A LATE AFTERNOON AND EVENING STORM FROM ACTIVITY THAT COULD EITHER DEVELOP IN-SITU INVOF A PIEDMONT SURFACE TROUGH AND/OR THAT IS MORE LIKELY TO INITIATE UPSTREAM OVER THE NC/SW VA MOUNTAINS AND INVOF THE AFOREMENTIONED FRONT...WHICH WOULD THEN PROPAGATE AWAY FROM THOSE FORCING MECHANISMS AND INTO THE NC PIEDMONT LATE THIS AFTERNOON AND EVENING. STRONG DIURNAL HEATING OF A DEEPLY MIXED BOUNDARY LAYER...AND ASSOCIATED STEEP LOW LEVEL LAPSE RATES AND 25-30 C DEWPOINT DEPRESSIONS...WOULD SUPPORT A CONDITIONAL RISK OF STRONG TO DAMAGING DOWNBURST WIND GUSTS IF CONVECTION INDEED DEVELOPS OVER OR PROPAGATES INTO...CENTRAL NC. HOWEVER...MID LEVEL FLOW AT THIS LATITUDE/OVER CENTRAL NC WILL REMAIN ONLY MODEST TO THE SOUTH OF THE MAIN BELT OF WESTERLIES AT THE BASE OF A BROAD TROUGH CENTERED NEAR JAMES BAY...SO ANY SEVERE OCCURRENCE SHOULD BE ISOLATED. HIGH TEMPERATURES NEAR OR SLIGHTLY ABOVE THOSE OF MON GIVEN A SLIGHT UPTICK IN FORECAST LOW LEVEL THICKNESS VALUES - UPPER 80S/AROUND 90 WHERE CLOUDS SHOULD BE MOST PREVALENT FROM KCTZ AND KGSB AND POINTS EASTWARD...TO 90-98 DEGREES ELSEWHERE...HOTTEST FROM AFP TO FAY. LOWS GENERALLY 70 TO 75...AFTER ANY CONVECTION THAT DOES OCCUR MOVES EAST AND/OR DISSIPATES BY LATE EVENING. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 350 AM TUESDAY... WHILE THE COLD FRONT WILL SETTLE SOUTH ACROSS CENTRAL NC AND SERVE AS A POSSIBLE TRIGGER FOR CONVECTION AGAIN WED AFTERNOON AND EVENING...GENERALLY WESTERLY FLOW ALOFT -INCLUDING A SIGNIFICANT DOWNSLOPE COMPONENT AT 850 MB- AND VEERED SURFACE FLOW INTO A PRE- FRONTAL TROUGH THAT THE MODELS INDICATE WILL HAVE DRIFTED INTO THE COASTAL PLAIN...SHOULD GENERALLY LIMIT COVERAGE. ANY SCATTERED OR WIDELY SO STORMS THAT DO FORM...HOWEVER...WOULD AGAIN POSE A RISK OF STRONG EVAPORATIVELY-ENHANCED WIND GUSTS. WEAK CAA NORTH OF THE BOUNDARY WILL TAKE THE EDGE OFF OF THE HEAT ACROSS THE NORTHERN PIEDMONT...WHERE LOWER 90S ARE EXPECTED...VERSUS MIDDLE TO UPPER 90S ONCE AGAIN OVER THE SOUTHERN PIEDMONT AND SANDHILLS. SLIGHTLY COOLER AND LESS HUMID AS THE FRONT SETTLES TO THE NEAR THE SC BORDER BY MORNING...WITH LOWS IN THE UPPER 60S TO AROUND 70 DEGREES. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 410 AM TUESDAY... THE COLD FRONT FORECAST TO BE NEAR THE NC-SC BORDER THURSDAY MORNING WILL MEANDER BACK TO THE NORTH ON THURSDAY...AS A WAVE OF LOW PRESSURE TRACKS FROM THE MID-MISSISSIPPI RIVER VALLEY REGION TOWARD THE OHIO VALLEY REGION IN RESPONSE TO A SHORTWAVE MOVING EAST FROM THE CENTRAL ROCKIES. THERE ARE STILL SIGNIFICANT MODEL DIFFERENCES IN THE AMPLITUDE/TIMING THE SYSTEM THAT RESULT IN BELOW AVERAGE FORECAST CONFIDENCE FOR LATE WEEK. THE NAM AND ECMWF SEEM TO BE MORE CONSISTENT IN SHOWING A DEEPER DISTURBANCE AND AND NOTICEABLY STRONGER SURFACE LOW THAT TRACKS JUST NORTH OF CENTRAL NC LATE THURSDAY INTO EARLY FRIDAY...WHILE THE GFS SHOWS A VARIETY OF DISTURBANCES IN WEST-NORTHWESTERLY FLOW ALOFT THAT EVENTUALLY EVOLVE INTO A DEEPER SHORTWAVE TROUGH CROSSING OUR REGION LATE FRIDAY. WILL CONTINUE BEST CHANCE POPS THURSDAY EVENING THROUGH FRIDAY AFTERNOON GIVEN THE AFOREMENTIONED CONSISTENCIES IN THE ECMWF AND NAM...THOUGH THE BEST COVERAGE MAY ULTIMATELY END UP TO OUR NORTH WITH THE RETREATING FRONTAL ZONE. WHILE THE STRONGEST MID-LEVEL WESTERLIES WILL RESIDE TO OUR NORTH DURING THIS PERIOD...THE AMPLITUDE OF THE DISTURBANCE DEPICTED IN THE ECMWF (ALBEIT IMPACTING THE AREA AT A POOR TIME DIURNALLY) AND THE PRESENCE OF THE FRONTAL ZONE SUGGEST A SEVERE THREAT ISN`T OUT OF THE QUESTION. THE TRAILING COLD FRONT WILL THEN CROSS THE AREA BY FRIDAY EVENING...USHERING IN SOME DRIER AIR AND LEAVING MOST OF THE CWA DRY AS THE FOCUS MOVES TOWARD THE COASTAL AREA FOR THE WEEKEND THE COMBINATION OF CLOUD COVER AND PERIODS OF SHOWERS/STORMS SHOULD LEAD TO HIGHS A BELOW NORMAL BY FRIDAY....REMAINING AT OR JUST BELOW NORMAL SATURDAY BEFORE SLOWLY TRENDING WARMER EARLY NEXT WEEK BENEATH RENEWED NORTHWESTERLY FLOW ALOFT. && .AVIATION /18Z TUESDAY THROUGH SATURDAY/... AS OF 100 PM TUESDAY... OF MOST IMMEDIATE CONCERN TO AVIATION INTERESTS ARE THE BANDS OF SCATTERED SHOWERS AND ISOLATED STORMS OVER THE COASTAL PLAIN OF NC... AN OUTWARD EXPANSION OF THE RAIN SHIELD ASSOCIATED WITH POTENT LOW PRESSURE NOW JUST OFF THE NRN SC COAST NEAR MYR. AS THIS LOW TRACKS TO THE NE JUST OFF THE SRN NC COAST AND SRN OUTER BANKS THROUGH EARLY EVENING... WE SHOULD CONTINUE TO SEE ISOLATED CELLS NEAR RWI/FAY AND PERHAPS NEARING RDU AS WELL. BRIEF MVFR TO HIGH-END IFR CONDITIONS ARE EXPECTED IN THESE SHOWERS. ELSEWHERE... ISOLATED TO SCATTERED STORMS MAY IMPACT INT/GSO LATE AFTERNOON... PERHAPS REACHING RDU BY EARLY EVENING BEFORE FIZZLING OUT BY MID EVENING AS THEY PROGRESS TO THE EAST. LOCALIZED WIND GUSTS OVER 40 MPH AND MVFR CONDITIONS ARE POSSIBLE IN/NEAR THESE SHOWERS/STORMS. VFR CONDITIONS SHOULD THEN DOMINATE INTO THE EARLY OVERNIGHT HOURS... BUT MVFR FOG IS POSSIBLE AT RWI/FAY AFTER 06Z TONIGHT... LIFTING/DISSIPATING BY 14Z WED MORNING. LOOKING BEYOND 18Z WED... MUCH OF WED SHOULD BE DRY WITH VFR CONDITIONS THROUGH EARLY EVENING... THEN THE WEATHER BECOMES MORE ACTIVE AS A STRONG UPPER LEVEL DISTURBANCE APPROACHES FROM THE WNW AND MOVES THROUGH THE REGION WED EVENING THROUGH EARLY FRI MORNING. WHILE VFR CONDITIONS WILL BE OBSERVED THROUGH THE MAJORITY OF THIS PERIOD... SCATTERED TO NUMEROUS SHOWERS AND STORMS ARE EXPECTED AT ANY TIME... ESPECIALLY LATE THU AFTERNOON INTO EARLY FRI MORNING... AND SUB-VFR CONDITIONS WILL BE POSSIBLE IN/NEAR ANY OF THESE SHOWERS AND STORMS... WITH POSSIBLE SUB-VFR STRATUS AND FOG BETWEEN BOUTS OF RAIN. IMPROVING CONDITIONS TO MAINLY VFR IS EXPECTED FRI AFTERNOON THROUGH SAT AS HIGH PRESSURE BUILDS IN. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...26/HARTFIELD NEAR TERM...HARTFIELD/26 SHORT TERM...26 LONG TERM...22 AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1039 AM EDT TUE AUG 4 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL SLOWLY SLIDE UP THE COAST TODAY BRINGING PERIODS OF SHOWERS AND THUNDERSTORMS. THIS MAY LEAD TO PERIODS OF HEAVY RAINFALL ALONG THE COAST. MORE TYPICAL SUMMERTIME CONDITIONS WILL DEVELOP WEDNESDAY THROUGH FRIDAY. A COLD FRONT MOVING CLOSER TO THE AREA WILL INCREASE THE CHANCE OF SHOWERS AND THUNDERSTORMS ONCE AGAIN THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM TUESDAY...WEAK LOW JUST OFF THE COAST EAST OF GEORGETOWN SOUTH CAROLINA CONTINUES TO CAUSE SHOWERS AND THUNDERSTORMS ACROSS THE AREA THIS MORNING. CONVECTION OVER LAND HAS INCREASED IN THE LAST FEW HOURS DUE TO AN INCREASE IN LOW LEVEL CONVERGENCE AND MOISTURE. DID NOT MAKE WHOLESALE CHANGES TO THE PREVIOUS FORECAST BUT DID TRIM/TWEAK POP GRADIENT AND VALUES BASED ON RECENT RADAR TRENDS. THIS RESULTED IN A SLIGHT LOWERING OF POP/QPF ALONG THE COAST AS WELL AS AN INCREASE IN POP/QPF ACROSS PORTIONS OF INLAND NC. CANNOT RULE OUT SOME LIGHT PRECIP ACROSS PORTIONS OF SC THIS AM AS THE LOW LIFTS NORTHEAST BUT CHANCES ARE RAPIDLY DIMINISHING. THE NORTH TO NORTHWEST FLOW AT THE LOW LEVELS AND WEAK SURFACE DIVERGENCE MAKE SIGNIFICANT CONVECTION DURING THE NEXT FEW HOURS UNLIKELY. CONVECTION MAY REDEVELOP THIS AFTERNOON IF THE LOW DEPARTS QUICKLY AND HEATING RESULTS IN SURFACE BASED INSTABILITY. THERE IS HOWEVER A FAIR AMOUNT OF DRY AIR ALOFT AROUND THE PERIPHERY OF THE MOISTURE PLUM WHICH WILL BE WORKING ITS WAY OVER THE AREA. PREVIOUS DISCUSSION FROM 630 AM FOLLOWS: ANOTHER WET DAY FOR THE COASTAL CAROLINAS AS SFC LOW PRESSURE CREEPS N-NE ALONG THE IMMEDIATE SOUTHEAST U.S. COAST...REACHING THE ILM SC CWA THIS AFTERNOON...AND THE ILM NC CWA THIS EVENING AND OVERNIGHT. THE LOW WILL BE ACCOMPANIED BY UPPER SUPPORT THAT WILL AID IN DRAWING IN THE RICH MOISTURE...PWS IN EXCESS OF 2 INCHES...FROM OFF THE ATLANTIC AS SEEN VIA LATEST KLTX VWP IN THE LOW TO MID LEVELS. AT THIS POINT...MODELS INDICATE THE BULK OF THE HEAVIEST RAIN AND UPPER DYNAMICS TO REMAIN JUST OVER THE ADJACENT ATLANTIC WATERS AS IT PASSES BY THE ILM CWA. POPS WILL BE ORIENTED LOWEST INLAND...ALONG AND WEST OF THE I-95 CORRIDOR...TO HIGHEST ALONG THE IMMEDIATE CAROLINA COASTS. THE GROUNDS HAVE BEEN ABSORBING THE RECENT RAINS LIKE A SPONGE OF LATE...AND WILL CONTINUE TO DO SO TODAY. EVENTHOUGH FFG VALUES ACROSS THE COASTAL COUNTIES HAVE DECREASED SOME...ITS JUST NOT LOW ENOUGH TO WARRANT A FLOOD WATCH AT THIS TIME GIVEN THE CURRENT QPF FORECAST FOR THE COASTAL CAROLINAS AT ONE HALF TO 1 INCH. WITH PWS PROGGED AT 2+ INCH AMOUNTS...THE FA STILL COULD EXPERIENCE ISOLATED HIGHER AMOUNTS FROM THE STRONGER AND MORE EFFICIENT CONVECTION. OVERALL...WILL LIKELY OBSERVE NUISANCE TYPE FLOODING OR PONDING OF WATER ACROSS THOSE NORMALLY PRONE AND VULNERABLE LOCATIONS. HAVE HIGHLIGHTED THIS FLOOD POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK. MAX TEMPS TO REACH THE 90S WELL INLAND...AND IN THE LOW TO MID 80S ALONG THE COAST. MIN TEMPS TO RANGE AROUND 70 INLAND TO THE UPPER 70S TO NEAR 80 AT THE COAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...HOT SUMMER WEATHER FOR THE SHORT TERM AS BERMUDA HIGH PRESSURE COMBINES WITH MID-LEVEL RIDGING...CREATING MORE TYPICAL SUMMERTIME WEATHER. WEDNESDAY LOOKS TO BE A VERY HOT DAY WITH WIDESPREAD MID AND UPR 90S ACROSS THE AREA. THIS IS DUE TO VERY WARM 850MB TEMPS ADVECTING EAST INTO THE CAROLINAS...AND COMBINING WITH A WARM/DRY DOWNSLOPE FLOW...SO EVEN COASTAL SECTIONS WILL RISE WELL INTO THE 90S AS THE SEA BREEZE GETS PINNED. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE WEDNESDAY...BUT DRIER AIR BEHIND THE DEPARTING LOW FROM TUESDAY WILL PREVENT ANYTHING BEYOND JUST A FEW STORMS. LOWS WEDNESDAY NIGHT WILL BE QUITE WARM...MID AND UPR 70S...POSSIBLY NEAR 80 ON THE BRUNSWICK COUNTY COAST. SIMILAR WEATHER FOR THURSDAY ALTHOUGH NOT QUITE AS HOT AS THE THICKNESSES BEGIN TO DECREASE AND MID-LEVEL FLOW BECOMES MORE SWLY. TEMPS ARE STILL EXPECTED TO BE ABOVE NORMAL...LOW 90S AT THE COAST AND MID 90S INLAND...BUT LIKE A FEW DEGREES COOLER THAN WEDNESDAY. STORM COVERAGE WILL BE SLIGHTLY HIGHER TOO THANKS TO GREATER INSTABILITY ON HIGHER DEWPOINTS AND STEEPER LAPSE RATES...BUT ONLY LOW-CHC POP IN A TYPICAL SUMMERTIME REGIME IS WARRANTED. ANOTHER WARM NIGHT EXPECTED THURSDAY NIGHT WITH LOWS REMAINING AT LEAST 5 DEGREES ABOVE CLIMO...MID 70S ACROSS THE AREA. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY...PATTERN CHANGE BEGINS FRIDAY AS TROUGHING ACROSS THE EASTERN CONUS RE-AMPLIFIES IN RESPONSE TO RIDGING EXPANDING ACROSS THE GREAT PLAINS. THIS WILL BE LED BY A POTENT VORT DRIVING A COLD FRONT INTO THE AREA ON FRIDAY...ALTHOUGH GUIDANCE HAS NOW DIVERGED ON THE TIMING AND PROGRESSION OF THIS SURFACE FEATURE. FOLLOWING WPC PROGS AS A REASONABLE SOLUTION...THE FRONT WILL APPROACH FRIDAY AND THEN LIKELY STALL THROUGH THE WKND...SIMILAR TO WHAT WE JUST EXPERIENCED THIS PAST WKND. HOWEVER...THE LONGWAVE TROUGH SHOULD BE A BIT DEEPER AND THUS THE FRONT HAS A BETTER CHANCE OF MOVING OFFSHORE SATURDAY...SO WILL OPTIMISTICALLY SHOW AT LEAST SOMEWHAT DRIER AIR SUNDAY AND MONDAY WITH TEMPS ACTUALLY BELOW CLIMO...AFTER SEASONABLE BUT WITH GOOD CHANCES FOR SHOWERS/TSTMS FRIDAY AND SATURDAY. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... AS OF 12Z...LOW PRESSURE TRACKING STEADILY UP THE COAST THIS MORNING. THE HRRR MODEL DISPLAYS THIS FEATURE FAIRLY WELL...WITH CONVECTION ALONG THE COAST THROUGH THE MORNING HOURS. WINDS COULD GUST TO NEAR 30 KTS IN THE STRONGEST CONVECTION...WITH INTERMITTENT IFR VISIBILITIES. THE INLAND TERMINALS WILL NOT SEE MUCH IN THE WAY OF CONVECTION...AS MOST OF THE MOISTURE RESIDES ON THE EAST SIDE OF THE LOW. GIVEN ENOUGH HEATING THIS AFTERNOON HOWEVER COULD TRIGGER SOME MAINLY ISOLATED SHOWERS INLAND. MOST OF THE ACTIVITY WILL END BY MID TO LATE AFTERNOON AS THE LOW TRACKS OUT OF THE REGION. EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH DIURNALLY DRIVEN SHRA/TSRA. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM TUESDAY...SLOW MOVING WEAK LOW IS RESULTING IN SOUTHWEST FLOW AROUND 20 KT ACROSS MUCH OF THE NEAR SHORE WATERS. THIS HAS PUSHED SEAS CLOSE TO 8 FT IN SOME AREAS AND THE SCA CONTINUES FOR ALL ZONES. SURFACE ANALYSIS IS SHOWING PINCHED GRADIENT JUST AHEAD OF THE LOW...RIGHT WHERE BUOYS ARE REPORTING THE HIGHEST WINDS/SEAS. THIS AREA OF ENHANCED WINDS SHOULD SLIDE OFF TO THE NORTHEAST AS THE LOW SLOWLY LIFTS NORTH-NORTHEAST TODAY. ONLY MINOR ADJUSTMENTS NEEDED TO PREVIOUS FORECAST. PREVIOUS DISCUSSION FROM 630 AM FOLLOWS: HAVE POSTED A SMALL CRAFT ADVISORY FOR ALL WATERS FOR TODAY THROUGH THE MAJORITY OF TONIGHT. THIS IN RESPONSE TO A SFC LOW MOVING N BY NE...MOVING ACROSS THE IMMEDIATE SC AND NC COASTS THIS AFTERNOON AND EVENING RESPECTIVELY. ENOUGH OF A TIGHTENED SFC PG DEVELOPS TO PRODUCE S-SW WINDS IN THE 15 TO 25 KT SPEEDS. GUSTS OVER 30 KT REMAINS POSSIBLE ESPECIALLY IF ANY MIXING FROM ALOFT DOWN TO THE OCEAN SFC OCCURS. LATEST MODELS AND THE KLTX VWP INDICATE 25 TO 35 KT WINDS JUST OFF THE OCEAN SFC. THE LOW WILL MOVE AWAY FROM THE AREA WATERS AFTER MIDNIGHT... LEAVING A SW-WSW 10-20 KT WIND IN ITS WAKE. SIGNIFICANT SEAS WILL BUILD TO 4 TO 7 FT..WITH THE 7 FOOTERS RESERVED FOR THE LOCAL WATERS OFF CAPE FEAR. THIS MAY BE A CONSERVATIVE SEAS FORECAST CONSIDERING THE 1 TO 3 FOOT UNDERLYING SE GROUND SWELL AT 10-11 SECOND PERIODS. OVERALL...DOMINANT PERIODS WILL RUN 7 SECONDS...INDICATIVE OF WIND DRIVEN WAVES DOMINATING THE SEAS. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...BERMUDA HIGH PRESSURE WILL BE THE DOMINANT FEATURE THIS PERIOD CREATING SW WINDS ACROSS THE WATERS. WIND SPEEDS WILL BE 10-15 KTS MOST OF THE PERIOD...BUT A SHARPENING PIEDMONT TROUGH EACH EVENING WILL HELP WINDS ACROSS THE WATERS RISE UP TOWARDS 20 KTS BRIEFLY WED AND THU EVE...BEFORE FALLING BACK AGAIN EACH NIGHT. THESE WINDS WILL BE THE PREDOMINANT DRIVER OF SEAS...WITH A 5 SEC SW WIND CHOP CREATING 3-4 FT SEAS...UP TO 5 FT AT TIMES DURING THE STRONGEST WINDS EACH EVENING. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 300 AM TUESDAY...TYPICAL BERMUDA HIGH PRESSURE REMAINS RIDGED ACROSS THE WATERS FRIDAY...AHEAD OF A COLD FRONT WHICH WILL APPROACH FROM THE NW AND THEN DROP ACROSS THE WATERS LATE SATURDAY. THIS COLD FRONTAL PASSAGE WILL DRIVE A WIND SHIFT TO THE NW LATE. SEAS WILL BE DRIVEN PREDOMINANTLY BY THE WINDS...WITH 3-4 FT SEAS EXPECTED FRIDAY...FALLING TO 2-3 FT SATURDAY AS THE SPEEDS EASE WITH THE FRONTAL PASSAGE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EDT WEDNESDAY FOR AMZ254-256. SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR AMZ250-252. && $$ NEAR TERM...III SHORT TERM...JDW LONG TERM...JDW AVIATION...43
AREA FORECAST DISCUSSION
NWS RALEIGH NC
955 AM EDT TUE AUG 4 2015 .SYNOPSIS...AN AREA OF LOW PRESSURE WILL TRACK FROM NEAR MYRTLE BEACH NORTHEASTWARD ALONG THE SOUTHERN OUTER BANKS OF NORTH CAROLINA THROUGH TONIGHT. MEANWHILE... A COLD FRONT WILL APPROACH FROM THE NORTHWEST AND SETTLE INTO NORTH CAROLINA ON WEDNESDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 955 AM TUESDAY... FORECAST IS IN GOOD SHAPE. LATEST SURFACE ANALYSIS SHOWS SURFACE LOW PRESSURE OFF THE NRN SC COAST POISED TO MOVE TO THE NORTHEAST TODAY NEAR THE SRN NC COAST AND SRN OUTER BANKS. A RATHER IMPRESSIVE SHIELD OF CONVECTION ACCOMPANIES THIS LOW... AND SOME OF THESE ELEMENTS HAVE SPREAD NORTHWESTWARD INTO THE SE CWA. THIS BEHAVIOR IS EXPECTED TO PERSIST THROUGH TODAY... RESULTING IN SCATTERED SHOWERS AND STORMS OVER THE SOUTHEAST COASTAL PLAIN EAST OF I-95. THIS IS IN LINE WITH NEARLY ALL COARSE AND HI-RES GUIDANCE INCLUDING THE SPC SSEO... NSSL WRF... AND NCAR ENSEMBLE OUTPUT. SUBSIDENCE ON THE WEST SIDE OF THIS FORMIDABLE LOW SHOULD HELP TEMPER MUCH OF THE CONVECTION MORE INLAND (NW OF A FAY-WILSON LINE)... HOWEVER FARTHER NW OVER THE NW AND FAR NRN PIEDMONT... SHEARED VORTICITY SPREADING ESE FROM NE/IA/MO CONVECTION INTO THE BROAD BASE OF THE MEAN LONGWAVE TROUGH WILL SPREAD INTO ERN KY/TN AND WRN VA/NC LATER THIS AFTERNOON THROUGH EVENING... LIKELY INSTIGATING ISOLATED TO SCATTERED CONVECTION ALONG EITHER AN OLD OUTFLOW AND/OR THE BAGGY PIEDMONT TROUGH... ALTHOUGH AS WAS THE CASE YESTERDAY... ENTRAINMENT OF DRY AIR WITHIN THE BELOW-NORMAL-PW ENVIRONMENT PERSISTING OVER THE WRN PIEDMONT OF NC WILL LIMIT COVERAGE/STRENGTH/LIFETIME OF ANY SUCH CONVECTION. THE HRRR AND NCAR ENSEMBLE PROBABILITIES BRING THIS CONVECTION INTO OUR NW CWA AROUND MID AFTERNOON... WITH A SLOW SOUTHEASTWARD DRIFT AND EVENTUAL DISSIPATION BY MID EVENING... IN LINE WITH THE CURRENT FORECAST WITH ONLY MINOR TWEAKS NEEDED. AFOREMENTIONED SUBSIDENCE SHOULD PROMPT GOOD HEATING PARTICULARLY OVER THE SRN AND ERN PIEDMONT AND WRN SANDHILLS (AWAY FROM THE COASTAL CLOUD SHIELD)... AND HIGHS IN THE MID-UPPER 90S APPEAR ATTAINABLE THERE... WITH LOW-MID 90S ELSEWHERE... COOLEST IN THE EXTREME ESE CWA. -GIH PREVIOUS DISCUSSION FROM 335 AM: A 1011 MB SURFACE LOW CENTERED JUST SOUTH OF KCHS IS FORECAST TO TRACK NORTHEASTWARD GENERALLY ALONG THE COAST OF THE CAROLINAS THROUGH TONIGHT. DEEP CONVECTION HAS BLOSSOMED DURING THE PAST COUPLE OF HOURS IN ASSOCIATION WITH THE LOW...AND EXTRAPOLATION OF THIS ACTIVITY (AND THE TRACK OF THE SURFACE LOW) SUGGESTS IT SHOULD REMAIN CONFINED FROM SAMPSON AND WAYNE COUNTIES AND ESPECIALLY POINTS EASTWARD...IN AXIS OF FOCUSED 925-850 MB MOISTURE TRANSPORT TO THE EAST OF AN INVERTED TROUGH AXIS FROM THE LOW CENTER. OTHERWISE...A PIEDMONT TROUGH WILL SHARPEN THIS AFTERNOON...AHEAD OF A COLD FRONT THAT WAS ANALYZED THIS MORNING FROM THE LOWER GREAT LAKES TO THE LOWER OH VALLEY. THE MODELS INDICATE THE COLD FRONT WILL SETTLE SOUTH ACROSS VA TONIGHT...TO NEAR THE NC BORDER BY WED MORNING. WILL RETAIN A 20-30 PERCENT CHANCE OF A LATE AFTERNOON AND EVENING STORM FROM ACTIVITY THAT COULD EITHER DEVELOP IN-SITU INVOF A PIEDMONT SURFACE TROUGH AND/OR THAT IS MORE LIKELY TO INITIATE UPSTREAM OVER THE NC/SW VA MOUNTAINS AND INVOF THE AFOREMENTIONED FRONT...WHICH WOULD THEN PROPAGATE AWAY FROM THOSE FORCING MECHANISMS AND INTO THE NC PIEDMONT LATE THIS AFTERNOON AND EVENING. STRONG DIURNAL HEATING OF A DEEPLY MIXED BOUNDARY LAYER...AND ASSOCIATED STEEP LOW LEVEL LAPSE RATES AND 25-30 C DEWPOINT DEPRESSIONS...WOULD SUPPORT A CONDITIONAL RISK OF STRONG TO DAMAGING DOWNBURST WIND GUSTS IF CONVECTION INDEED DEVELOPS OVER OR PROPAGATES INTO...CENTRAL NC. HOWEVER...MID LEVEL FLOW AT THIS LATITUDE/OVER CENTRAL NC WILL REMAIN ONLY MODEST TO THE SOUTH OF THE MAIN BELT OF WESTERLIES AT THE BASE OF A BROAD TROUGH CENTERED NEAR JAMES BAY...SO ANY SEVERE OCCURRENCE SHOULD BE ISOLATED. HIGH TEMPERATURES NEAR OR SLIGHTLY ABOVE THOSE OF MON GIVEN A SLIGHT UPTICK IN FORECAST LOW LEVEL THICKNESS VALUES - UPPER 80S/AROUND 90 WHERE CLOUDS SHOULD BE MOST PREVALENT FROM KCTZ AND KGSB AND POINTS EASTWARD...TO 90-98 DEGREES ELSEWHERE...HOTTEST FROM AFP TO FAY. LOWS GENERALLY 70 TO 75...AFTER ANY CONVECTION THAT DOES OCCUR MOVES EAST AND/OR DISSIPATES BY LATE EVENING. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 350 AM TUESDAY... WHILE THE COLD FRONT WILL SETTLE SOUTH ACROSS CENTRAL NC AND SERVE AS A POSSIBLE TRIGGER FOR CONVECTION AGAIN WED AFTERNOON AND EVENING...GENERALLY WESTERLY FLOW ALOFT -INCLUDING A SIGNIFICANT DOWNSLOPE COMPONENT AT 850 MB- AND VEERED SURFACE FLOW INTO A PRE- FRONTAL TROUGH THAT THE MODELS INDICATE WILL HAVE DRIFTED INTO THE COASTAL PLAIN...SHOULD GENERALLY LIMIT COVERAGE. ANY SCATTERED OR WIDELY SO STORMS THAT DO FORM...HOWEVER...WOULD AGAIN POSE A RISK OF STRONG EVAPORATIVELY-ENHANCED WIND GUSTS. WEAK CAA NORTH OF THE BOUNDARY WILL TAKE THE EDGE OFF OF THE HEAT ACROSS THE NORTHERN PIEDMONT...WHERE LOWER 90S ARE EXPECTED...VERSUS MIDDLE TO UPPER 90S ONCE AGAIN OVER THE SOUTHERN PIEDMONT AND SANDHILLS. SLIGHTLY COOLER AND LESS HUMID AS THE FRONT SETTLES TO THE NEAR THE SC BORDER BY MORNING...WITH LOWS IN THE UPPER 60S TO AROUND 70 DEGREES. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 410 AM TUESDAY... THE COLD FRONT FORECAST TO BE NEAR THE NC-SC BORDER THURSDAY MORNING WILL MEANDER BACK TO THE NORTH ON THURSDAY...AS A WAVE OF LOW PRESSURE TRACKS FROM THE MID-MISSISSIPPI RIVER VALLEY REGION TOWARD THE OHIO VALLEY REGION IN RESPONSE TO A SHORTWAVE MOVING EAST FROM THE CENTRAL ROCKIES. THERE ARE STILL SIGNIFICANT MODEL DIFFERENCES IN THE AMPLITUDE/TIMING THE SYSTEM THAT RESULT IN BELOW AVERAGE FORECAST CONFIDENCE FOR LATE WEEK. THE NAM AND ECMWF SEEM TO BE MORE CONSISTENT IN SHOWING A DEEPER DISTURBANCE AND AND NOTICEABLY STRONGER SURFACE LOW THAT TRACKS JUST NORTH OF CENTRAL NC LATE THURSDAY INTO EARLY FRIDAY...WHILE THE GFS SHOWS A VARIETY OF DISTURBANCES IN WEST-NORTHWESTERLY FLOW ALOFT THAT EVENTUALLY EVOLVE INTO A DEEPER SHORTWAVE TROUGH CROSSING OUR REGION LATE FRIDAY. WILL CONTINUE BEST CHANCE POPS THURSDAY EVENING THROUGH FRIDAY AFTERNOON GIVEN THE AFOREMENTIONED CONSISTENCIES IN THE ECMWF AND NAM...THOUGH THE BEST COVERAGE MAY ULTIMATELY END UP TO OUR NORTH WITH THE RETREATING FRONTAL ZONE. WHILE THE STRONGEST MID-LEVEL WESTERLIES WILL RESIDE TO OUR NORTH DURING THIS PERIOD...THE AMPLITUDE OF THE DISTURBANCE DEPICTED IN THE ECMWF (ALBEIT IMPACTING THE AREA AT A POOR TIME DIURNALLY) AND THE PRESENCE OF THE FRONTAL ZONE SUGGEST A SEVERE THREAT ISN`T OUT OF THE QUESTION. THE TRAILING COLD FRONT WILL THEN CROSS THE AREA BY FRIDAY EVENING...USHERING IN SOME DRIER AIR AND LEAVING MOST OF THE CWA DRY AS THE FOCUS MOVES TOWARD THE COASTAL AREA FOR THE WEEKEND THE COMBINATION OF CLOUD COVER AND PERIODS OF SHOWERS/STORMS SHOULD LEAD TO HIGHS A BELOW NORMAL BY FRIDAY....REMAINING AT OR JUST BELOW NORMAL SATURDAY BEFORE SLOWLY TRENDING WARMER EARLY NEXT WEEK BENEATH RENEWED NORTHWESTERLY FLOW ALOFT. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 800 AM TUESDAY... MOIST SOUTHERLY LOW LEVEL FLOW ON THE NNE PERIPHERY OF AN AREA OF LOW PRESSURE NEAR THE CENTRAL SC COAST THIS MORNING WILL MAINTAIN SCATTERED TO BROKEN IFR-MVFR RANGE CLOUDS AT RDU/FAY/RWI...WHICH WILL LIFT AND SCATTER TO VFR BETWEEN 13-16Z. WHILE AN ISOLATED TO WIDELY SCATTERED STORM WILL BE POSSIBLE AT ALL SITES IN ADVANCE OF AN APPROACHING COLD FRONT LATE THIS AFTERNOON AND EVENING... PARTICULARLY FROM INT/GSO TO RDU...AN AXIS OF MORE NUMEROUS SHOWERS AND STORMS WILL DEVELOP AND AFFECT THE EASTERN CAROLINAS...INCLUDING FAY AND VICINITY...BEGINNING AS EARLY AS THIS MORNING...BEFORE DIMINISHING BY THIS EVENING AS THE LOW PASSES BY TO THE EAST. ASIDE FROM A SMALL CHANCE OF A SHOWER/STORM WED-WED NIGHT... GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH MID-WEEK. A FRONTAL SYSTEM WILL CROSS THE MIDDLE ATLANTIC REGION AND RESULT IN A PEAK IN THE PROBABILITY OF SHOWERS AND STORMS...AND SUB-VFR CONDITIONS...NC LATE THU-FRI. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...26/HARTFIELD NEAR TERM...HARTFIELD/26 SHORT TERM...26 LONG TERM...22 AVIATION...26
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
651 AM EDT TUE AUG 4 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL SLOWLY SLIDE UP THE COAST TODAY BRINGING PERIODS OF SHOWERS AND THUNDERSTORMS. THIS WILL CREATE PERIODS OF HEAVY RAINFALL...ESPECIALLY ALONG THE COAST. MORE TYPICAL SUMMERTIME CONDITIONS WILL DEVELOP WEDNESDAY THROUGH FRIDAY. A COLD FRONT MOVING CLOSER TO THE AREA WILL INCREASE THE CHANCE OF SHOWERS AND THUNDERSTORMS ONCE AGAIN THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM TUESDAY...ANOTHER WET DAY FOR THE COASTAL CAROLINAS ...AS SFC LOW PRESSURE CREEPS N-NE ALONG THE IMMEDIATE SOUTHEAST U.S. COAST...REACHING THE ILM SC CWA THIS AFTERNOON...AND THE ILM NC CWA THIS EVENING AND OVERNIGHT. THE LOW WILL BE ACCOMPANIED BY UPPER SUPPORT THAT WILL AID IN DRAWING IN THE RICH MOISTURE...PWS IN EXCESS OF 2 INCHES...FROM OFF THE ATLANTIC AS SEEN VIA LATEST KLTX VWP IN THE LOW TO MID LEVELS. AT THIS POINT...MODELS INDICATE THE BULK OF THE HEAVIEST RAIN AND UPPER DYNAMICS TO REMAIN JUST OVER THE ADJACENT ATLANTIC WATERS AS IT PASSES BY THE ILM CWA. POPS WILL BE ORIENTED LOWEST INLAND...ALONG AND WEST OF THE I-95 CORRIDOR...TO HIGHEST ALONG THE IMMEDIATE CAROLINA COASTS. THE GROUNDS HAVE BEEN ABSORBING THE RECENT RAINS LIKE A SPONGE OF LATE...AND WILL CONTINUE TO DO SO TODAY. EVENTHOUGH FFG VALUES ACROSS THE COASTAL COUNTIES HAVE DECREASED SOME...ITS JUST NOT LOW ENOUGH TO WARRANT A FLOOD WATCH AT THIS TIME GIVEN THE CURRENT QPF FORECAST FOR THE COASTAL CAROLINAS AT ONE HALF TO 1 INCH. WITH PWS PROGGED AT 2+ INCH AMOUNTS...THE FA STILL COULD EXPERIENCE ISOLATED HIGHER AMOUNTS FROM THE STRONGER AND MORE EFFICIENT CONVECTION. OVERALL...WILL LIKELY OBSERVE NUISANCE TYPE FLOODING OR PONDING OF WATER ACROSS THOSE NORMALLY PRONE AND VULNERABLE LOCATIONS. HAVE HIGHLIGHTED THIS FLOOD POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK. MAX TEMPS TO REACH THE 90S WELL INLAND...AND IN THE LOW TO MID 80S ALONG THE COAST. MIN TEMPS TO RANGE AROUND 70 INLAND TO THE UPPER 70S TO NEAR 80 AT THE COAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...HOT SUMMER WEATHER FOR THE SHORT TERM AS BERMUDA HIGH PRESSURE COMBINES WITH MID-LEVEL RIDGING...CREATING MORE TYPICAL SUMMERTIME WEATHER. WEDNESDAY LOOKS TO BE A VERY HOT DAY WITH WIDESPREAD MID AND UPR 90S ACROSS THE AREA. THIS IS DUE TO VERY WARM 850MB TEMPS ADVECTING EAST INTO THE CAROLINAS...AND COMBINING WITH A WARM/DRY DOWNSLOPE FLOW...SO EVEN COASTAL SECTIONS WILL RISE WELL INTO THE 90S AS THE SEA BREEZE GETS PINNED. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE WEDNESDAY...BUT DRIER AIR BEHIND THE DEPARTING LOW FROM TUESDAY WILL PREVENT ANYTHING BEYOND JUST A FEW STORMS. LOWS WEDNESDAY NIGHT WILL BE QUITE WARM...MID AND UPR 70S...POSSIBLY NEAR 80 ON THE BRUNSWICK COUNTY COAST. SIMILAR WEATHER FOR THURSDAY ALTHOUGH NOT QUITE AS HOT AS THE THICKNESSES BEGIN TO DECREASE AND MID-LEVEL FLOW BECOMES MORE SWLY. TEMPS ARE STILL EXPECTED TO BE ABOVE NORMAL...LOW 90S AT THE COAST AND MID 90S INLAND...BUT LIKE A FEW DEGREES COOLER THAN WEDNESDAY. STORM COVERAGE WILL BE SLIGHTLY HIGHER TOO THANKS TO GREATER INSTABILITY ON HIGHER DEWPOINTS AND STEEPER LAPSE RATES...BUT ONLY LOW-CHC POP IN A TYPICAL SUMMERTIME REGIME IS WARRANTED. ANOTHER WARM NIGHT EXPECTED THURSDAY NIGHT WITH LOWS REMAINING AT LEAST 5 DEGREES ABOVE CLIMO...MID 70S ACROSS THE AREA. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY...PATTERN CHANGE BEGINS FRIDAY AS TROUGHING ACROSS THE EASTERN CONUS RE-AMPLIFIES IN RESPONSE TO RIDGING EXPANDING ACROSS THE GREAT PLAINS. THIS WILL BE LED BY A POTENT VORT DRIVING A COLD FRONT INTO THE AREA ON FRIDAY...ALTHOUGH GUIDANCE HAS NOW DIVERGED ON THE TIMING AND PROGRESSION OF THIS SURFACE FEATURE. FOLLOWING WPC PROGS AS A REASONABLE SOLUTION...THE FRONT WILL APPROACH FRIDAY AND THEN LIKELY STALL THROUGH THE WKND...SIMILAR TO WHAT WE JUST EXPERIENCED THIS PAST WKND. HOWEVER...THE LONGWAVE TROUGH SHOULD BE A BIT DEEPER AND THUS THE FRONT HAS A BETTER CHANCE OF MOVING OFFSHORE SATURDAY...SO WILL OPTIMISTICALLY SHOW AT LEAST SOMEWHAT DRIER AIR SUNDAY AND MONDAY WITH TEMPS ACTUALLY BELOW CLIMO...AFTER SEASONABLE BUT WITH GOOD CHANCES FOR SHOWERS/TSTMS FRIDAY AND SATURDAY. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 12Z...LOW PRESSURE TRACKING STEADILY UP THE COAST THIS MORNING. THE HRRR MODEL DISPLAYS THIS FEATURE FAIRLY WELL...WITH CONVECTION ALONG THE COAST THROUGH THE MORNING HOURS. WINDS COULD GUST TO NEAR 30 KTS IN THE STRONGEST CONVECTION...WITH INTERMITTENT IFR VISIBILITIES. THE INLAND TERMINALS WILL NOT SEE MUCH IN THE WAY OF CONVECTION...AS MOST OF THE MOISTURE RESIDES ON THE EAST SIDE OF THE LOW. GIVEN ENOUGH HEATING THIS AFTERNOON HOWEVER COULD TRIGGER SOME MAINLY ISOLATED SHOWERS INLAND. MOST OF THE ACTIVITY WILL END BY MID TO LATE AFTERNOON AS THE LOW TRACKS OUT OF THE REGION. EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH DIURNALLY DRIVEN SHRA/TSRA. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM TUESDAY...HAVE POSTED A SMALL CRAFT ADVISORY FOR ALL WATERS FOR TODAY THROUGH THE MAJORITY OF TONIGHT. THIS IN RESPONSE TO A SFC LOW MOVING N BY NE...MOVING ACROSS THE IMMEDIATE SC AND NC COASTS THIS AFTERNOON AND EVENING RESPECTIVELY. ENOUGH OF A TIGHTENED SFC PG DEVELOPS TO PRODUCE S-SW WINDS IN THE 15 TO 25 KT SPEEDS. GUSTS OVER 30 KT REMAINS POSSIBLE ESPECIALLY IF ANY MIXING FROM ALOFT DOWN TO THE OCEAN SFC OCCURS. LATEST MODELS AND THE KLTX VWP INDICATE 25 TO 35 KT WINDS JUST OFF THE OCEAN SFC. THE LOW WILL MOVE AWAY FROM THE AREA WATERS AFTER MIDNIGHT... LEAVING A SW-WSW 10-20 KT WIND IN ITS WAKE. SIGNIFICANT SEAS WILL BUILD TO 4 TO 7 FT..WITH THE 7 FOOTERS RESERVED FOR THE LOCAL WATERS OFF CAPE FEAR. THIS MAY BE A CONSERVATIVE SEAS FORECAST CONSIDERING THE 1 TO 3 FOOT UNDERLYING SE GROUND SWELL AT 10-11 SECOND PERIODS. OVERALL...DOMINANT PERIODS WILL RUN 7 SECONDS...INDICATIVE OF WIND DRIVEN WAVES DOMINATING THE SEAS. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...BERMUDA HIGH PRESSURE WILL BE THE DOMINANT FEATURE THIS PERIOD CREATING SW WINDS ACROSS THE WATERS. WIND SPEEDS WILL BE 10-15 KTS MOST OF THE PERIOD...BUT A SHARPENING PIEDMONT TROUGH EACH EVENING WILL HELP WINDS ACROSS THE WATERS RISE UP TOWARDS 20 KTS BRIEFLY WED AND THU EVE...BEFORE FALLING BACK AGAIN EACH NIGHT. THESE WINDS WILL BE THE PREDOMINANT DRIVER OF SEAS...WITH A 5 SEC SW WIND CHOP CREATING 3-4 FT SEAS...UP TO 5 FT AT TIMES DURING THE STRONGEST WINDS EACH EVENING. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 300 AM TUESDAY...TYPICAL BERMUDA HIGH PRESSURE REMAINS RIDGED ACROSS THE WATERS FRIDAY...AHEAD OF A COLD FRONT WHICH WILL APPROACH FROM THE NW AND THEN DROP ACROSS THE WATERS LATE SATURDAY. THIS COLD FRONTAL PASSAGE WILL DRIVE A WIND SHIFT TO THE NW LATE. SEAS WILL BE DRIVEN PREDOMINANTLY BY THE WINDS...WITH 3-4 FT SEAS EXPECTED FRIDAY...FALLING TO 2-3 FT SATURDAY AS THE SPEEDS EASE WITH THE FRONTAL PASSAGE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EDT WEDNESDAY FOR AMZ254-256. SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR AMZ250-252. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...JDW LONG TERM...JDW AVIATION...DCH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
626 AM EDT TUE AUG 4 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL SLOWLY SLIDE UP THE COAST TODAY BRINGING PERIODS OF SHOWERS AND THUNDERSTORMS. THIS WILL CREATE PERIODS OF HEAVY RAINFALL...ESPECIALLY ALONG THE COAST. MORE TYPICAL SUMMERTIME CONDITIONS WILL DEVELOP WEDNESDAY THROUGH FRIDAY. A COLD FRONT MOVING CLOSER TO THE AREA WILL INCREASE THE CHANCE OF SHOWERS AND THUNDERSTORMS ONCE AGAIN THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 345 AM TUESDAY...LOOKS LIKE ANOTHER WET DAY FOR THE COASTAL CAROLINAS...AS SFC LOW PRESSURE CREEPS N-NE ALONG THE IMMEDIATE SOUTHEAST U.S. COAST...REACHING THE ILM SC CWA THIS AFTERNOON...AND THE ILM NC CWA THIS EVENING AND OVERNIGHT. THE LOW WILL BE ACCOMPANIED BY UPPER SUPPORT THAT WILL AID IN DRAWING IN THE MOISTURE FROM OFF THE ATLANTIC AS SEEN VIA LATEST KLTX VWP. AT THIS POINT...MODELS INDICATE THE BULK OF THE HEAVIEST RAIN TO REMAIN OVER THE ADJACENT ATLANTIC WATERS. POPS WILL BE ORIENTED LOWEST INLAND...ALONG AND WEST OF THE I-95 CORRIDOR...TO HIGHEST ALONG THE IMMEDIATE CAROLINA COASTS. THE GROUNDS HAVE BEEN ABSORBING THE RECENT RAINS LIKE A SPONGE OF LATE...AND WILL CONTINUE TO DO SO TODAY. EVENTHOUGH FFG VALUES ACROSS THE COASTAL COUNTIES HAVE DECREASED SOME...ITS JUST NOT LOW ENOUGH TO WARRANT A FLOOD WATCH AT THIS TIME GIVEN THE CURRENT QPF FORECAST FOR THE COASTAL CAROLINAS AT ONE HALF TO 1 INCH. WITH PWS PROGGED AT 2+ INCH AMOUNTS...THE FA STILL COULD EXPERIENCE ISOLATED HIGHER AMOUNTS FROM THE STRONGER AND MORE EFFICIENT CONVECTION. OVERALL...WILL LIKELY OBSERVE NUISANCE TYPE FLOODING OR PONDING OF WATER ACROSS THOSE NORMALLY PRONE AND VULNERABLE LOCATIONS. HAVE HIGHLIGHTED THIS FLOOD POTENTIAL IN THE HAZARDOUS WEATHER OUTLOOK. MAX TEMPS TO REACH THE 90S WELL INLAND...AND IN THE LOW TO MID 80S ALONG THE COAST. MIN TEMPS TO RANGE AROUND 70 INLAND TO THE UPPER 70S TO NEAR 80 AT THE COAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...HOT SUMMER WEATHER FOR THE SHORT TERM AS BERMUDA HIGH PRESSURE COMBINES WITH MID-LEVEL RIDGING...CREATING MORE TYPICAL SUMMERTIME WEATHER. WEDNESDAY LOOKS TO BE A VERY HOT DAY WITH WIDESPREAD MID AND UPR 90S ACROSS THE AREA. THIS IS DUE TO VERY WARM 850MB TEMPS ADVECTING EAST INTO THE CAROLINAS...AND COMBINING WITH A WARM/DRY DOWNSLOPE FLOW...SO EVEN COASTAL SECTIONS WILL RISE WELL INTO THE 90S AS THE SEA BREEZE GETS PINNED. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE WEDNESDAY...BUT DRIER AIR BEHIND THE DEPARTING LOW FROM TUESDAY WILL PREVENT ANYTHING BEYOND JUST A FEW STORMS. LOWS WEDNESDAY NIGHT WILL BE QUITE WARM...MID AND UPR 70S...POSSIBLY NEAR 80 ON THE BRUNSWICK COUNTY COAST. SIMILAR WEATHER FOR THURSDAY ALTHOUGH NOT QUITE AS HOT AS THE THICKNESSES BEGIN TO DECREASE AND MID-LEVEL FLOW BECOMES MORE SWLY. TEMPS ARE STILL EXPECTED TO BE ABOVE NORMAL...LOW 90S AT THE COAST AND MID 90S INLAND...BUT LIKE A FEW DEGREES COOLER THAN WEDNESDAY. STORM COVERAGE WILL BE SLIGHTLY HIGHER TOO THANKS TO GREATER INSTABILITY ON HIGHER DEWPOINTS AND STEEPER LAPSE RATES...BUT ONLY LOW-CHC POP IN A TYPICAL SUMMERTIME REGIME IS WARRANTED. ANOTHER WARM NIGHT EXPECTED THURSDAY NIGHT WITH LOWS REMAINING AT LEAST 5 DEGREES ABOVE CLIMO...MID 70S ACROSS THE AREA. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY...PATTERN CHANGE BEGINS FRIDAY AS TROUGHING ACROSS THE EASTERN CONUS RE-AMPLIFIES IN RESPONSE TO RIDGING EXPANDING ACROSS THE GREAT PLAINS. THIS WILL BE LED BY A POTENT VORT DRIVING A COLD FRONT INTO THE AREA ON FRIDAY...ALTHOUGH GUIDANCE HAS NOW DIVERGED ON THE TIMING AND PROGRESSION OF THIS SURFACE FEATURE. FOLLOWING WPC PROGS AS A REASONABLE SOLUTION...THE FRONT WILL APPROACH FRIDAY AND THEN LIKELY STALL THROUGH THE WKND...SIMILAR TO WHAT WE JUST EXPERIENCED THIS PAST WKND. HOWEVER...THE LONGWAVE TROUGH SHOULD BE A BIT DEEPER AND THUS THE FRONT HAS A BETTER CHANCE OF MOVING OFFSHORE SATURDAY...SO WILL OPTIMISTICALLY SHOW AT LEAST SOMEWHAT DRIER AIR SUNDAY AND MONDAY WITH TEMPS ACTUALLY BELOW CLIMO...AFTER SEASONABLE BUT WITH GOOD CHANCES FOR SHOWERS/TSTMS FRIDAY AND SATURDAY. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 12Z...LOW PRESSURE TRACKING STEADILY UP THE COAST THIS MORNING. THE HRRR MODEL DISPLAYS THIS FEATURE FAIRLY WELL...WITH CONVECTION ALONG THE COAST THROUGH THE MORNING HOURS. WINDS COULD GUST TO NEAR 30 KTS IN THE STRONGEST CONVECTION...WITH INTERMITTENT IFR VISIBILITIES. THE INLAND TERMINALS WILL NOT SEE MUCH IN THE WAY OF CONVECTION...AS MOST OF THE MOISTURE RESIDES ON THE EAST SIDE OF THE LOW. GIVEN ENOUGH HEATING THIS AFTERNOON HOWEVER COULD TRIGGER SOME MAINLY ISOLATED SHOWERS INLAND. MOST OF THE ACTIVITY WILL END BY MID TO LATE AFTERNOON AS THE LOW TRACKS OUT OF THE REGION. EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH DIURNALLY DRIVEN SHRA/TSRA. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 415 AM TUESDAY...HAVE POSTED A SMALL CRAFT ADVISORY FOR ALL WATERS FOR TODAY THROUGH THE MAJORITY OF TONIGHT. THIS IN RESPONSE TO A SFC LOW MOVING N BY NE AND MOVING ACROSS THE IMMEDIATE SC AND NC COASTS THIS AFTERNOON AND EVENING RESPECTIVELY. ENOUGH OF A TIGHTENED SFC PG DEVELOPS TO PRODUCE S-SW WINDS IN THE 15 TO 25 KT SPEEDS. GUSTS OVER 30 KT REMAINS POSSIBLE ESPECIALLY WITH ANY MIXING FROM ALOFT DOWN TO THE OCEAN SFC OCCURS. LATEST MODELS AND THE KLTX VWP INDICATE 25 TO 35 KT WINDS JUST OFF THE OCEAN SFC. THE LOW WILL MOVE AWAY FROM THE AREA WATERS AFTER MIDNIGHT... LEAVING A SW-WSW 10-20 KT WIND IN ITS WAKE ACROSS THE LOCAL WATERS. SIGNIFICANT SEAS WILL BUILD TO 4 TO 7 FT..WITH THE 7 FOOTERS RESERVED FOR THE LOCAL WATERS OFF CAPE FEAR. THIS MAY BE A CONSERVATIVE SEAS FORECAST CONSIDERING THE 1 TO 3 FOOT UNDERLYING SE GROUND SWELL AT 10-11 SECOND PERIODS. OVERALL...DOMINANT PERIODS WILL RUN 7 SECONDS...INDICATIVE OF WIND DRIVEN WAVES DOMINATING THE SIGNIFICANT SEAS. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 AM TUESDAY...BERMUDA HIGH PRESSURE WILL BE THE DOMINANT FEATURE THIS PERIOD CREATING SW WINDS ACROSS THE WATERS. WIND SPEEDS WILL BE 10-15 KTS MOST OF THE PERIOD...BUT A SHARPENING PIEDMONT TROUGH EACH EVENING WILL HELP WINDS ACROSS THE WATERS RISE UP TOWARDS 20 KTS BRIEFLY WED AND THU EVE...BEFORE FALLING BACK AGAIN EACH NIGHT. THESE WINDS WILL BE THE PREDOMINANT DRIVER OF SEAS...WITH A 5 SEC SW WIND CHOP CREATING 3-4 FT SEAS...UP TO 5 FT AT TIMES DURING THE STRONGEST WINDS EACH EVENING. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 300 AM TUESDAY...TYPICAL BERMUDA HIGH PRESSURE REMAINS RIDGED ACROSS THE WATERS FRIDAY...AHEAD OF A COLD FRONT WHICH WILL APPROACH FROM THE NW AND THEN DROP ACROSS THE WATERS LATE SATURDAY. THIS COLD FRONTAL PASSAGE WILL DRIVE A WIND SHIFT TO THE NW LATE. SEAS WILL BE DRIVEN PREDOMINANTLY BY THE WINDS...WITH 3-4 FT SEAS EXPECTED FRIDAY...FALLING TO 2-3 FT SATURDAY AS THE SPEEDS EASE WITH THE FRONTAL PASSAGE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 3 AM EDT WEDNESDAY FOR AMZ254-256. SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR AMZ250-252. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...JDW LONG TERM...JDW AVIATION...43
AREA FORECAST DISCUSSION
NWS BISMARCK ND
928 PM CDT WED AUG 5 2015 .UPDATE... ISSUED AT 921 PM CDT WED AUG 5 2015 VERY ISOLATED THUNDERSTORMS CONTINUE EAST OF THE MISSOURI RIVER. AN AREA OF THUNDERSTORMS WILL BE MOVING INTO THE SOUTHWEST AFTER 10 PM CDT. UPDATED POPS FOR CURRENT TRENDS. WATER VAPOR IMAGERY SHOWS SHORTWAVE TROUGH MOVING THROUGH NORTH CENTRAL WYOMING. THIS WILL LIFT INTO SOUTHWEST NORTH DAKOTA OVERNIGHT. CURRENT FORECAST TRENDING OK. UPDATE ISSUED AT 638 PM CDT WED AUG 5 2015 WARM FRONT ACROSS CENTRAL NORTH DAKOTA WILL BE THE FOCUS FOR SCATTERED TO ISOLATED THUNDERSTORMS ACROSS CENTRAL AND EASTERN NORTH DAKOTA THIS EVENING. A COLD FRONT ACROSS SOUTHEAST SASKATCHEWAN WILL MOVE SOUTHEAST AND BE THE FOCUS FOR NUMEROUS THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA AFTER MIDNIGHT. HRRR MODEL CONTINUES TO SPREAD THUNDERSTORMS SOUTHWEST TO NORTHEAST ACROSS THE STATE LATE TONIGHT WITH A MID LEVEL SHORTWAVE TROUGH CURRENTLY OVER EASTERN IDAHO. THIS STILL LOOKS REASONABLE. MAIN UPDATES TO FORECAST WERE CURRENT CONDITIONS AND TIMING OF POPS WEST. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 302 PM CDT WED AUG 5 2015 HIGHLIGHTS OF THE SHORT TERM IS CONVECTIVE POTENTIAL THIS AFTERNOON AND HEAVY RAINFALL ON THURSDAY. FOR THE REMAINDER OF THE AFTERNOON...EXPECTING ISOLATED TO SCATTERED SURFACE BASED CONVECTIVE DEVELOPMENT EAST OF THE WARM FRONT NEAR US HIGHWAY 85. 18 UTC RAP ANALYSIS DEPICTS 1500-2000 J/KG OF ML CAPE AND DEEP LAYER SHEAR OF 30-40 KTS AHEAD OF THE BOUNDARY. THUS...A FEW STRONG TO POSSIBLY SEVERE STORMS ARE POSSIBLE...IN LINE WITH THE 18-19 UTC HRRR ITERATIONS AND SPC DAY 1 OUTLOOK. A STRONG SHORTWAVE IS FORECAST TO PROPAGATE OUT OF THE INTERMOUNTAIN WEST AND ONTO THE NORTHERN PLAINS LATE THIS EVENING AND TONIGHT...AND STRENGTHEN THROUGH THE DAY ON THURSDAY. EXPECTING WIDESPREAD THUNDERSTORMS SOUTH OF US HIGHWAY 2 ENTERING THE SOUTHWEST TONIGHT...AND FOCUSING CENTRAL THROUGH THURSDAY AFTERNOON. PWATS OF 1.50 TO 1.75 INCHES WITH TALL...SKINNY CAPE PROFILES...AND WEAK WINDS THROUGHOUT THE TROPOSPHERE SUPPORTING SLOW STORM MOTIONS ALL POINT TO A HEAVY RAINFALL THREAT. AREAS THAT WILL RESIDE IN THIS ENVIRONMENT THE LONGEST IS THE SOUTH CENTRAL AND JAMES RIVER VALLEY LATE THURSDAY MORNING THROUGH THE EVENING. THIS IS SUPPORTED BY 00 UTC GEFS QPF MODEL CLIMATE IN THE MAXIMUM PERCENTILES FOR THESE AREAS THURSDAY AFTERNOON...WHICH HAS BEEN NOTED AS A FLASH FLOOD SIGNAL IN PREVIOUS EVENTS ACROSS THE CONUS. THUS...HAVE ISSUED A FLASH FLOOD WATCH FOR THE SOUTH CENTRAL AND JAMES RIVER VALLEY FOR THURSDAY. ALTHOUGH SOME OF THESE AREAS HAVE BEEN RELATIVELY DRY OVER THE RECENT WEEKS...POTENTIAL EXCESSIVE RAINFALL RATES MAY STILL LEAD TO FLASH FLOODING EVEN WITH DRY SOILS. FLASH FLOODING OF URBAN AREAS...INCLUDING MANDAN...BISMARCK AND JAMESTOWN ARE ALSO POSSIBLE WITH THESE SLOW MOVING...HEAVY RAINFALL PRODUCING STORMS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 302 PM CDT WED AUG 5 2015 SHORTWAVE TROUGH WILL BE EXITING THE JAMES RIVER VALLEY THURSDAY NIGHT/06-12 FRIDAY AS LIKELY POPS DWINDLE AND THE PRECIPITATION COMES TO AN END. UPPER LOW WILL MOVE ACROSS SOUTHERN CANADA FRIDAY THROUGH SATURDAY DRAGGING TWO SURFACE COLD FRONTS THROUGH...ONE FRIDAY NIGHT AND A SECONDARY COLD FRONT SATURDAY. FRIDAY LOOKS DRY WITH THE INITIAL FRONT. HOWEVER FRIDAY NIGHT AND SATURDAY...ASSOCIATED WITH THE SECOND FRONT WILL BE THE RIGHT ENTRANCE REGION OF A 70KT-80KT JET STREAK SLIDING THROUGH CENTRAL NORTH DAKOTA ATOP OF A SURFACE LOW PRESSURE SCOOTING ACROSS NORTHERN SOUTH DAKOTA. AN AREA OF PRECIPITATION DEVELOPS OVER OR NEAR SOUTHERN NORTH DAKOTA SATURDAY IN RESPONSE TO THE LOW LEVEL CONVERGENCE AND THE UPPER LEVEL DIVERGENCE AREA ASSOCIATED WITH THE JET. ALTHOUGH WEAK NORTHWEST FLOW ENSUES SATURDAY NIGHT INTO SUNDAY...THERE IS SOME QUESTION AS TO WHETHER OR NOT THE FRONT STALLS ALONG/NEAR OR SOUTH OF THE SOUTHERN BORDER SUNDAY FOR CONTINUED PRECIPITATION CHANCES. AS OF NOW IT APPEARS THAT CHANCES FOR PRECIPITATION BEGIN ALONG INTERSTATE 94 AND INCREASE SOUTH TOWARDS THE BORDER SUNDAY. THEREAFTER A CENTRAL CONUS UPPER LEVEL RIDGE DEVELOPS WITH A TROUGH SETTLING INTO THE WEST FOR DRY AND WARM CONDITIONS MONDAY AND TUESDAY. THERE MAY BE POTENTIAL SHORTWAVES TRYING TO BREAK DOWN THE RIDGE BY MID WEEK OR SIGNS OF THE RIDGE SHIFTING EAST A BIT FOR POSSIBLE SHOWERS AND THUNDERSTORMS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 921 PM CDT WED AUG 5 2015 MAIN HAZARDS TO AVIATION WILL BE THUNDERSTORMS AND POSSIBLE MVFR TO IFR CONDITIONS IN THE THUNDERSTORM VCNTY. AT 9 PM CDT...A WARM FRONT EXTENDED ACROSS CENTRAL NORTH DAKOTA IN THE VICINITY OF HIGHWAY 83. A COLD FRONT EXTENDED ACROSS SOUTHERN SASKATCHEWAN. THE COLD FRONT WILL MOVE SOUTHEAST AND WILL BECOME THE FOCUS FOR NUMEROUS THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA AFTER 06Z. CONDITIONS MAY BECOME MVFR TO IFR IN THE AREAS OF THUNDERSTORMS KDIK-KBIS AFT 14Z. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR NDZ019>023-025-034>037-042-045>048-050-051. && $$ UPDATE...WAA SHORT TERM...AYD LONG TERM...KS AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
652 PM CDT WED AUG 5 2015 .UPDATE... ISSUED AT 638 PM CDT WED AUG 5 2015 WARM FRONT ACROSS CENTRAL NORTH DAKOTA WILL BE THE FOCUS FOR SCATTERED TO ISOLATED THUNDERSTORMS ACROSS CENTRAL AND EASTERN NORTH DAKOTA THIS EVENING. A COLD FRONT ACROSS SOUTHEAST SASKATCHEWAN WILL MOVE SOUTHEAST AND BE THE FOCUS FOR NUMEROUS THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA AFTER MIDNIGHT. HRRR MODEL CONTINUES TO SPREAD THUNDERSTORMS SOUTHWEST TO NORTHEAST ACROSS THE STATE LATE TONIGHT WITH A MID LEVEL SHORTWAVE TROUGH CURRENTLY OVER EASTERN IDAHO. THIS STILL LOOKS REASONABLE. MAIN UPDATES TO FORECAST WERE CURRENT CONDITIONS AND TIMING OF POPS WEST. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 302 PM CDT WED AUG 5 2015 HIGHLIGHTS OF THE SHORT TERM IS CONVECTIVE POTENTIAL THIS AFTERNOON AND HEAVY RAINFALL ON THURSDAY. FOR THE REMAINDER OF THE AFTERNOON...EXPECTING ISOLATED TO SCATTERED SURFACE BASED CONVECTIVE DEVELOPMENT EAST OF THE WARM FRONT NEAR US HIGHWAY 85. 18 UTC RAP ANALYSIS DEPICTS 1500-2000 J/KG OF ML CAPE AND DEEP LAYER SHEAR OF 30-40 KTS AHEAD OF THE BOUNDARY. THUS...A FEW STRONG TO POSSIBLY SEVERE STORMS ARE POSSIBLE...IN LINE WITH THE 18-19 UTC HRRR ITERATIONS AND SPC DAY 1 OUTLOOK. A STRONG SHORTWAVE IS FORECAST TO PROPAGATE OUT OF THE INTERMOUNTAIN WEST AND ONTO THE NORTHERN PLAINS LATE THIS EVENING AND TONIGHT...AND STRENGTHEN THROUGH THE DAY ON THURSDAY. EXPECTING WIDESPREAD THUNDERSTORMS SOUTH OF US HIGHWAY 2 ENTERING THE SOUTHWEST TONIGHT...AND FOCUSING CENTRAL THROUGH THURSDAY AFTERNOON. PWATS OF 1.50 TO 1.75 INCHES WITH TALL...SKINNY CAPE PROFILES...AND WEAK WINDS THROUGHOUT THE TROPOSPHERE SUPPORTING SLOW STORM MOTIONS ALL POINT TO A HEAVY RAINFALL THREAT. AREAS THAT WILL RESIDE IN THIS ENVIRONMENT THE LONGEST IS THE SOUTH CENTRAL AND JAMES RIVER VALLEY LATE THURSDAY MORNING THROUGH THE EVENING. THIS IS SUPPORTED BY 00 UTC GEFS QPF MODEL CLIMATE IN THE MAXIMUM PERCENTILES FOR THESE AREAS THURSDAY AFTERNOON...WHICH HAS BEEN NOTED AS A FLASH FLOOD SIGNAL IN PREVIOUS EVENTS ACROSS THE CONUS. THUS...HAVE ISSUED A FLASH FLOOD WATCH FOR THE SOUTH CENTRAL AND JAMES RIVER VALLEY FOR THURSDAY. ALTHOUGH SOME OF THESE AREAS HAVE BEEN RELATIVELY DRY OVER THE RECENT WEEKS...POTENTIAL EXCESSIVE RAINFALL RATES MAY STILL LEAD TO FLASH FLOODING EVEN WITH DRY SOILS. FLASH FLOODING OF URBAN AREAS...INCLUDING MANDAN...BISMARCK AND JAMESTOWN ARE ALSO POSSIBLE WITH THESE SLOW MOVING...HEAVY RAINFALL PRODUCING STORMS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 302 PM CDT WED AUG 5 2015 SHORTWAVE TROUGH WILL BE EXITING THE JAMES RIVER VALLEY THURSDAY NIGHT/06-12 FRIDAY AS LIKELY POPS DWINDLE AND THE PRECIPITATION COMES TO AN END. UPPER LOW WILL MOVE ACROSS SOUTHERN CANADA FRIDAY THROUGH SATURDAY DRAGGING TWO SURFACE COLD FRONTS THROUGH...ONE FRIDAY NIGHT AND A SECONDARY COLD FRONT SATURDAY. FRIDAY LOOKS DRY WITH THE INITIAL FRONT. HOWEVER FRIDAY NIGHT AND SATURDAY...ASSOCIATED WITH THE SECOND FRONT WILL BE THE RIGHT ENTRANCE REGION OF A 70KT-80KT JET STREAK SLIDING THROUGH CENTRAL NORTH DAKOTA ATOP OF A SURFACE LOW PRESSURE SCOOTING ACROSS NORTHERN SOUTH DAKOTA. AN AREA OF PRECIPITATION DEVELOPS OVER OR NEAR SOUTHERN NORTH DAKOTA SATURDAY IN RESPONSE TO THE LOW LEVEL CONVERGENCE AND THE UPPER LEVEL DIVERGENCE AREA ASSOCIATED WITH THE JET. ALTHOUGH WEAK NORTHWEST FLOW ENSUES SATURDAY NIGHT INTO SUNDAY...THERE IS SOME QUESTION AS TO WHETHER OR NOT THE FRONT STALLS ALONG/NEAR OR SOUTH OF THE SOUTHERN BORDER SUNDAY FOR CONTINUED PRECIPITATION CHANCES. AS OF NOW IT APPEARS THAT CHANCES FOR PRECIPITATION BEGIN ALONG INTERSTATE 94 AND INCREASE SOUTH TOWARDS THE BORDER SUNDAY. THEREAFTER A CENTRAL CONUS UPPER LEVEL RIDGE DEVELOPS WITH A TROUGH SETTLING INTO THE WEST FOR DRY AND WARM CONDITIONS MONDAY AND TUESDAY. THERE MAY BE POTENTIAL SHORTWAVES TRYING TO BREAK DOWN THE RIDGE BY MID WEEK OR SIGNS OF THE RIDGE SHIFTING EAST A BIT FOR POSSIBLE SHOWERS AND THUNDERSTORMS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 638 PM CDT WED AUG 5 2015 MAIN HAZARDS TO AVIATION WILL BE THUNDERSTORMS AND POSSIBLE MVFR TO IFR CONDITIONS IN THE VCNTY. AT 6 PM CDT...A WARM FRONT EXTENDEDACROSS CENTRAL NORTH DAKOTA IN THE VICINITY OF HIGHWAY 83. A COLD FRONT EXTENDED ACROSS SOUTHERN SASKATCHEWAN. THE COLD FRONT WILL MOVE SOUTHEAST AND WILL BECOME THE FOCUS FOR NUMEROUS THUNDE4RSTORMAS ACROSS WEST AND CENTRAL NORTH DAKOTA AFTER 06Z. CONDITIONS MAY BECOME MVFR TO IFR IN THE AREAS OF THUNDERSTORMS KDIK-KBIS AFT 14Z. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR NDZ019>023-025-034>037-042-045>048-050-051. && $$ UPDATE...WAA SHORT TERM...AYD LONG TERM...KS AVIATION...WAA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
642 PM EDT TUE AUG 4 2015 .SYNOPSIS... A WEAKENING COLD FRONT WILL DROP ACROSS THE AREA OVERNIGHT. THE FRONT WILL DISSIPATE WEDNESDAY AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES AND OHIO VALLEY. THURSDAY LOW PRESSURE WILL MOVE INTO THE LOWER OHIO VALLEY AS THE HIGH MOVES EAST TO NEW ENGLAND. FRIDAY HIGH PRESSURE WILL BUILD BACK TOWARD OHIO AS THE LOW MOVES TO THE EAST COAST. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... JUST MINOR CHANGES. BACKED OFF ON PRECIP CHANCES FOR THIS EVENING. PREVIOUS...FOR THIS EVENING AND TONIGHT THE UPPER LOW REMAINS IN QUEBEC NEAR HUDSON BAY WITH THE UPPER TROUGH SOUTHWEST ACROSS THE GREAT LAKES AND NORTHERN OHIO VALLEY. WATER VAPOR IMAGERY SHOWS A WEAK IMPULSE MOVING THROUGH THE WESTERN LAKES THIS AFTERNOON WITH MODELS SHOWING THE SHORT WAVE ROTATING THROUGH THE BASE OF THE TROUGH ACROSS NRN OHIO BUT MOSTLY NWRN PA. AT THE SURFACE A WEAKENING COLD FRONT WILL DROP ACROSS THE LAKE AND REACH INTO THE AREA BEFORE DISSIPATING WEDNESDAY. THE HRRR SHOWS SCATTERED CONVECTION DEVELOPING TO OUR NORTH LATE AFTERNOON INTO EVENING MAINLY DUE TO HEATING. OVERNIGHT HOWEVER AM CONCERNED THAT A FEW SHOWERS DEVELOP IN RESPONSE TO THE SHORT WAVE THAT MOVE INTO NERN OHIO OR NWRN PA. IN ADDITION...850MB TEMPS CONTINUE TO DROP OVERNIGHT REACHING +9 TO +10C BY 12Z VC +13C TODAY. NOT A BIG CHANGE BUT BUFKIT DOES SHOW CONDITIONAL INSTABILITY TO THE LAKE. WILL HAVE A CHANCE POP THIS EVENING FAR NERN OHIO AND NWRN PA DROPPING TO A SLIGHT CHANCE OVERNIGHT. LOWS FROM THE MID 50S TO NEAR 60. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/... HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES AND OHIO VALLEY AGAIN ON WEDNESDAY. CONCERNED ABOUT ANY ONGOING SHOWER OR TWO ALONG THE LAKESHORE EAST OF KCLE AT FIRST BUT THAT SHOULD DISSIPATE QUICKLY THROUGH THE MORNING AS THE AIRMASS MIXES. OTHERWISE EXPECT PARTLY CLOUDY SKIES FOR THE DAY. THE HIGH WILL MOVE EAST AND NORTH OVER THE LAKES AFTER MIDNIGHT WEDNESDAY NIGHT AS LOW PRESSURE MOVES FROM THE CENTRAL PLAINS TO SOUTHERN IL. MODELS A LITTLE CLOSER WITH THE SOLUTION VS YDAY WITH MORE OF A CONSENSUS OF MOST OF THE PRECIP ACROSS SOUTHERN AND CENTRAL OHIO. WILL BRING A CHANCE POP INTO THE FAR SOUTH FOR THURSDAY AND THURSDAY EVENING BUT THIS COULD END UP TOO HIGH GIVEN TRENDS. FRIDAY HIGH PRESSURE BUILDS BACK IN FROM THE NORTH. AFTERNOON TEMPS MOSTLY IN THE 70S WED- THURS AND CLOSER TO 80 FRIDAY. LOWS IN THE 50S TO NEAR 60. && .LONG TERM /SATURDAY THROUGH TUESDAY/... THE BROAD RIDGE OVER THE PLAINS WILL START TO BUILD EASTWARD INTO THE OHIO VALLEY BEFORE THE TROUGH DEEPENS AGAIN EARLY NEXT WEEK. SHORTWAVE ENERGY MOVING AROUND THE RIDGE WILL TAKE A WEAK AREA OF LOW PRESSURE NORTH OF LAKE ERIE ON SATURDAY WHILE HIGH PRESSURE GENERALLY REMAINS IN CONTROL ACROSS THE OHIO VALLEY. WESTERLY FLOW AND WEAK WARM ADVECTION WILL SET UP BEHIND THIS FEATURE WITH HIGHS IN THE LOW 80S ON SUNDAY. MOISTURE INCREASES FROM SUNDAY TO MONDAY AS A SERIES OF ACTIVE WAVES MOVES AROUND THE RIDGE ACROSS THE LOWER GREAT LAKES REGION AHEAD OF THE DEEPENING TROUGH TO THE NORTH. WILL CARRY A CHANCE OF SHOWERS AND THUNDERSTORMS FROM SUNDAY NIGHT ON AS MOISTURE INCREASES. KEPT HIGHS CLOSE TO 80 GIVEN THE POTENTIAL FOR CLOUDS AND SHOWERS. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE TAF CYCLE. SCT CLOUDS NEAR 5K FEET WILL BECOME BROKEN AT SEVERAL SITES THIS EVENING AS A TROUGH MOVES THROUGH. AN ISOLATED SHOWER IS POSSIBLE AT ERI THIS EVENING BUT CHANCES ARE LOW ENOUGH THAT WILL NOT INCLUDE IN TAF AT THIS TIME. WESTERLY WINDS NEAR 10 KNOTS MAY OCCASIONALLY GUST TO 18 KNOTS THIS AFTERNOON BEFORE DROPPING TO 6 KNOTS OR LESS TONIGHT. WINDS WILL GRADUALLY SHIFT FROM SOUTHWEST TONIGHT TO NORTHWEST EARLY TUESDAY MORNING. OUTLOOK...NON VFR WEATHER POSSIBLE LATE WEDNESDAY THROUGH FRIDAY. && .MARINE... WEST WINDS OF 10 TO 20 KNOTS WILL WEAKEN AS THEY VEER TO NORTHWEST OVERNIGHT WITH THE PASSAGE OF A WEAK TROUGH. HIGH PRESSURE OVER THE UPPER MIDWEST WILL BUILD OVER THE GREAT LAKES ON WEDNESDAY WITH NORTHEAST TO EAST WINDS DEVELOPING. EAST TO NORTHEAST WINDS OF 10-15 KNOTS WILL CONTINUE THURSDAY AS A WEAK AREA OF LOW PRESSURE MOVES THROUGH THE OHIO VALLEY. WINDS WILL GENERALLY BE 15 KNOTS OR LESS THROUGH AT LEAST THE FIRST HALF OF THE WEEKEND AS HIGH PRESSURE EXPANDS OVER THE EASTERN GREAT LAKES. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK/KUBINA SHORT TERM...TK LONG TERM...KEC AVIATION...KUBINA MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
351 PM EDT TUE AUG 4 2015 .SYNOPSIS... A WEAKENING COLD FRONT WILL DROP ACROSS THE AREA OVERNIGHT. THE FRONT WILL DISSIPATE WEDNESDAY AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES AND OHIO VALLEY. THURSDAY LOW PRESSURE WILL MOVE INTO THE LOWER OHIO VALLEY AS THE HIGH MOVES EAST TO NEW ENGLAND. FRIDAY HIGH PRESSURE WILL BUILD BACK TOWARD OHIO AS THE LOW MOVES TO THE EAST COAST. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... FOR THIS EVENING AND TONIGHT THE UPPER LOW REMAINS IN QUEBEC NEAR HUDSON BAY WITH THE UPPER TROUGH SOUTHWEST ACROSS THE GREAT LAKES AND NORTHERN OHIO VALLEY. WATER VAPOR IMAGERY SHOWS A WEAK IMPULSE MOVING THROUGH THE WESTERN LAKES THIS AFTERNOON WITH MODELS SHOWING THE SHORT WAVE ROTATING THROUGH THE BASE OF THE TROUGH ACROSS NRN OHIO BUT MOSTLY NWRN PA. AT THE SURFACE A WEAKENING COLD FRONT WILL DROP ACROSS THE LAKE AND REACH INTO THE AREA BEFORE DISSIPATING WEDNESDAY. THE HRRR SHOWS SCATTERED CONVECTION DEVELOPING TO OUR NORTH LATE AFTERNOON INTO EVENING MAINLY DUE TO HEATING. OVERNIGHT HOWEVER AM CONCERNED THAT A FEW SHOWERS DEVELOP IN RESPONSE TO THE SHORT WAVE THAT MOVE INTO NERN OHIO OR NWRN PA. IN ADDITION...850MB TEMPS CONTINUE TO DROP OVERNIGHT REACHING +9 TO +10C BY 12Z VC +13C TODAY. NOT A BIG CHANGE BUT BUFKIT DOES SHOW CONDITIONAL INSTABILITY TO THE LAKE. WILL HAVE A CHANCE POP THIS EVENING FAR NERN OHIO AND NWRN PA DROPPING TO A SLIGHT CHANCE OVERNIGHT. LOWS FROM THE MID 50S TO NEAR 60. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/... HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES AND OHIO VALLEY AGAIN ON WEDNESDAY. CONCERNED ABOUT ANY ONGOING SHOWER OR TWO ALONG THE LAKESHORE EAST OF KCLE AT FIRST BUT THAT SHOULD DISSIPATE QUICKLY THROUGH THE MORNING AS THE AIRMASS MIXES. OTHERWISE EXPECT PARTLY CLOUDY SKIES FOR THE DAY. THE HIGH WILL MOVE EAST AND NORTH OVER THE LAKES AFTER MIDNIGHT WEDNESDAY NIGHT AS LOW PRESSURE MOVES FROM THE CENTRAL PLAINS TO SOUTHERN IL. MODELS A LITTLE CLOSER WITH THE SOLUTION VS YDAY WITH MORE OF A CONSENSUS OF MOST OF THE PRECIP ACROSS SOUTHERN AND CENTRAL OHIO. WILL BRING A CHANCE POP INTO THE FAR SOUTH FOR THURSDAY AND THURSDAY EVENING BUT THIS COULD END UP TOO HIGH GIVEN TRENDS. FRIDAY HIGH PRESSURE BUILDS BACK IN FROM THE NORTH. AFTERNOON TEMPS MOSTLY IN THE 70S WED- THURS AND CLOSER TO 80 FRIDAY. LOWS IN THE 50S TO NEAR 60. && .LONG TERM /SATURDAY THROUGH TUESDAY/... THE BROAD RIDGE OVER THE PLAINS WILL START TO BUILD EASTWARD INTO THE OHIO VALLEY BEFORE THE TROUGH DEEPENS AGAIN EARLY NEXT WEEK. SHORTWAVE ENERGY MOVING AROUND THE RIDGE WILL TAKE A WEAK AREA OF LOW PRESSURE NORTH OF LAKE ERIE ON SATURDAY WHILE HIGH PRESSURE GENERALLY REMAINS IN CONTROL ACROSS THE OHIO VALLEY. WESTERLY FLOW AND WEAK WARM ADVECTION WILL SET UP BEHIND THIS FEATURE WITH HIGHS IN THE LOW 80S ON SUNDAY. MOISTURE INCREASES FROM SUNDAY TO MONDAY AS A SERIES OF ACTIVE WAVES MOVES AROUND THE RIDGE ACROSS THE LOWER GREAT LAKES REGION AHEAD OF THE DEEPENING TROUGH TO THE NORTH. WILL CARRY A CHANCE OF SHOWERS AND THUNDERSTORMS FROM SUNDAY NIGHT ON AS MOISTURE INCREASES. KEPT HIGHS CLOSE TO 80 GIVEN THE POTENTIAL FOR CLOUDS AND SHOWERS. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... VFR CONDITIONS WILL CONTINUE THROUGH THE TAF CYCLE. SCT CLOUDS NEAR 5K FEET WILL BECOME BROKEN AT SEVERAL SITES THIS EVENING AS A TROUGH MOVES THROUGH. AN ISOLATED SHOWER IS POSSIBLE AT ERI THIS EVENING BUT CHANCES ARE LOW ENOUGH THAT WILL NOT INCLUDE IN TAF AT THIS TIME. WESTERLY WINDS NEAR 10 KNOTS MAY OCCASIONALLY GUST TO 18 KNOTS THIS AFTERNOON BEFORE DROPPING TO 6 KNOTS OR LESS TONIGHT. WINDS WILL GRADUALLY SHIFT FROM SOUTHWEST TONIGHT TO NORTHWEST EARLY TUESDAY MORNING. OUTLOOK...NON VFR WEATHER POSSIBLE LATE WEDNESDAY THROUGH FRIDAY. && .MARINE... WEST WINDS OF 10 TO 20 KNOTS WILL WEAKEN AS THEY VEER TO NORTHWEST OVERNIGHT WITH THE PASSAGE OF A WEAK TROUGH. HIGH PRESSURE OVER THE UPPER MIDWEST WILL BUILD OVER THE GREAT LAKES ON WEDNESDAY WITH NORTHEAST TO EAST WINDS DEVELOPING. EAST TO NORTHEAST WINDS OF 10-15 KNOTS WILL CONTINUE THURSDAY AS A WEAK AREA OF LOW PRESSURE MOVES THROUGH THE OHIO VALLEY. WINDS WILL GENERALLY BE 15 KNOTS OR LESS THROUGH AT LEAST THE FIRST HALF OF THE WEEKEND AS HIGH PRESSURE EXPANDS OVER THE EASTERN GREAT LAKES. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...TK NEAR TERM...TK SHORT TERM...TK LONG TERM...KEC AVIATION...KEC MARINE...KEC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
334 AM EDT TUE AUG 4 2015 .SYNOPSIS... A COLD FRONT WILL PUSH SOUTHEAST AND THROUGH THE STATE EARLY THIS MORNING. HIGH PRESSURE WILL DOMINATE THE MIDWEEK BEFORE UNSETTLED CONDITIONS RETURN FOR THURSDAY AND FRIDAY AS A SLOW MOVING FRONT MOVES BACK INTO THE REGION. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... SHORTWAVE AND ASSOC SFC COLD FRONT PRODUCING SOME STRONG TSRA EARLY THIS AM ACROSS PARTS OF SOUTH CENTRAL PA. SFC ANALYSIS INDICATES COLD FRONT IS ONLY JUST ENTERING THE NW MTNS AT 07Z AND NEAR TERM MDLS SUGGEST IT MAY TAKE UNTIL LATE AM TO CLEAR LANCASTER CO. HOWEVER...MID LVL SHORTWAVE AND ASSOC LG SCALE FORCING WILL SWEEP EAST OF THE REGION BY DAWN. THUS...EXPECT BACK EDGE OF SCT CONVECTION TO RAPIDLY EXIT THE EASTERN COUNTIES BTWN 08Z-10Z...AS THE LATEST HRRR DEPICTS. CLEARING SKIES...LGT WIND AND WET GROUND IS ALREADY PROMOTING PATCHY DENSE FOG ACROSS THE NW MTNS AS OF 07Z AND EXPECT PATCHY FOG TO DEVELOP ACROSS THE REST OF CENTRAL PA ARND DAWN...AS CLEARING SPREADS EAST. TEMPS ON TRACK TO BOTTOM OUT FROM THE U50S ACROSS THE NW MTNS...TO NR 70F OVR THE LOWER SUSQ VALLEY. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... UPPER TROUGH AND ASSOC CHILLY MID LVL TEMPS SHOULD SUPPORT SCT DIURNAL CONVECTION ACROSS THE N MTNS THIS AFTN. A SHOT OF ANOMALOUSLY DRY AIR...AS SEEN IN LOOP OF SATL-DERIVED PWATS...WILL SLIDE FROM THE MIDWEST INTO SOUTHERN PA TODAY...LIKELY RESULTING IN MSUNNY AND DRY WX OVER THAT PART OF THE STATE. MDL 8H TEMPS RANGING FROM 13C-16C SHOULD TRANSLATE TO MAX TEMPS FROM THE M70S OVR THE NW MTNS...TO THE U80S ACROSS THE LOWER SUSQ VALLEY. HAVE INCREASED AFTN WGUSTS TO 15-20KTS BASED ON AMT OF MIXING EXPECTED AND MDL 850 WIND FIELDS. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... THE UPPER LOW OVER NORTHERN QUEBEC SHOULD CONTINUE TO DRIFT TO THE NORTHEAST AND ZONAL TO SLIGHTLY NORTHWEST FLOW IS EXPECTED TO FOLLOW AS A QUASI-STATIONARY BOUNDARY HANGS OUT JUST TO THE SOUTH OF THE STATE. UNCERTAINTY REMAINS IN THE PLACEMENT OF THE BOUNDARY SO WILL KEEP SOME POP IN THE SRN PART OF THE STATE...BUT MOST LOCATIONS WILL BE DRY UNTIL THURSDAY INTO THURSDAY NIGHT. THEN A STACKED LOW WILL SLIDE EASTWARD FROM THE MID MISSISSIPPI VALLEY AND MAY MAKE A MORE-OR- LESS CONSTANT RAIN INSTEAD OF SHOWERY/CONVECTIVE PRECIP. THE UPPER LEVEL LOW WILL FINALLY MOVE OFF LATE NEXT WEEKEND WHICH WILL BE A HERALD FOR QUIETER WEATHER. TEMPERATURES SHOULD TREND COOLER LATER IN THE WEEK BEFORE WARMING UP INTO NEXT WEEK. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... SCATTERED SHOWERS AND TSTMS WILL CONTINUE TO MOVE WEST TO EAST ACROSS THE AIRSPACE THROUGH INTO THE PREDAWN HOURS. RADAR TRENDS ARE STILL FAVORING THE SRN 1/2 OF THE AIRSPACE WITH THE GREATEST COVERAGE AND RISK OF TSTM IMPACTS. THE LATEST HRRR/COSPA SUGGESTS STORMS DO NOT EXIT THE ERN AIRSPACE IN ZNY SECTOR UNTIL 08-10Z. WHILE THE OVERALL CONVECTIVE COVERAGE HAS INCREASED SINCE 00Z...SUSTAINED TERMINAL IMPACTS/SUB-VFR SHOULD BE LIMITED AS THE STORMS ARE PROGRESSING STEADILY EWD. THE OTHER POTENTIAL AVN CONCERN IS IFR FOG OR LOW CIGS DEVELOPING DURING THE PREDAWN HOURS AS SKIES CLEAR. GUIDANCE SEEMS TO FAVOR THE WRN TAFS GIVEN COMBO OF WLY UPSLOPE FLOW AND NARROWING DEWPT DEPRESSIONS. CONFIDENCE REMAINS LOW AND THE 06Z SCHEDULED ISSUANCE CAN FURTHER ADDRESS THIS IF NEEDED. FOR TUESDAY...LOOK FOR VFR CONDS WITH SCT-BKN CIGS 050 AND SFC WIND GUSTS 15-20KTS 15-22Z. OUTLOOK... WED...VFR. NO SIG WX. THU-FRI...VFR/MVFR WITH RAIN LKLY AS LOW PRES TRACKS SOUTH OF CENTRAL PA. SAT...VFR WITH A LOW CHC OF MVFR IN ISOLATED P.M SHRA/TSTMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...FITZGERALD/LA CORTE NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD/LAMBERT LONG TERM...DANGELO/CERU AVIATION...STEINBUGL
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
824 PM MDT WED AUG 5 2015 .UPDATE... ISSUED AT 821 PM MDT WED AUG 5 2015 00Z KUNR SOUNDING SHOWED DECENT SUPPORT FOR WIND...WHICH DID OCCUR WITH CONVECTION WEST OF RAPID CITY. WATER VAPOUR SHOWED RESPONSIBLE SHORTWAVE PLOWING NORTHEAST FROM WY INTO THE DAKOTAS. SECONDARY WAVE NOTED ACROSS NORTHWEST WY...WHICH THE 00Z GUIDANCE PICKS UP ON AND MOVES NORTHEAST INTO ND OVERNIGHT. TAIL END OF WAVE MAY PRODUCE ANOTHER ROUND OF -SHRA/-TSRA ACROSS THE CWA LATER THIS EVENING BEHIND INITIAL WAVE WHICH IS MOVING ONTO THE SD PLAINS. STRENGTH OF MUCAPE SLOWLY WANES OVERNIGHT. FORECAST TWEAKED FOR TIMING...BUT LARGELY IN GOOD SHAPE. && .SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT ISSUED AT 218 PM MDT WED AUG 5 2015 UPPER WAVE CONTINUES TO APPROACH THE REGION...AS UPPER LOW CIRCULATES OVER SOUTHWEST CANADA. WEAK SHOWERS ACROSS NORTHEAST WYOMING HAVE BEEN DISSIPATING AS THEY MOVE EASTWARD...WITH JUST SOME CLOUDS PUSHING INTO THE CWA. WITH LIGHT AND VARIABLE WINDS...TEMPS ARE GENERALLY IN THE 80S. SHOWERS AND THUNDERSTORMS STILL EXPECTED TO DEVELOP ALONG A LINE OF FRONTOGENESIS/Q-VECTOR CONVERGENCE ACROSS THE WESTERN CWA AND EXPAND EASTWARD. MODELS ARE HINTING AT AN INITIAL WAVE WITH BEST FORCING JUST NORTHWEST OF THE CWA BRINGING A BAND OF STORMS THROUGH THE NORTHERN HILLS AND NORTHWESTERN SD...WITH A SECONDARY WAVE IMMEDIATELY FOLLOWING WITH SCATTERED SHOWERS/STORMS. HRRR THIS MORNING WAS PRETTY CONSISTENT WITH A SQUALL LINE MOVING ACROSS THE NORTHERN HILLS AND NORTHWEST SD EARLY THIS EVENING...BUT LATER RUNS ARE SHOWING A MORE SCATTERED FORM. MLCAPE IS UNIMPRESSIVE AROUND 750 J/KG ON THE PLAINS WITH 1500 J/KG OVER THE HILLS...BUT SHEAR IS 35-45 KTS SO WOULD NOT RULE OUT A STRONG TO SEVERE STORM. MAIN THREAT WILL BE STRONG WINDS. SURFACE LOW WILL MOVE ACROSS SD THURSDAY. A TIGHT PRESSURE GRADIENT BEHIND THE LOW WILL CREATE SOME BREEZY NORTHWEST WINDS ACROSS THE SD PLAINS AND ALSO BRING IN SOME COOLER AIR TO NORTHWESTERN SD. SHOWERS/THUNDERSTORMS WILL CONTINUE ACROSS NORTHWESTERN/CENTRAL SD DURING THE DAY UNTIL THE WAVE FINALLY TRANSITIONS EASTWARD OUT OF THE REGION. DRY WEATHER IS THEN EXPECTED FOR THURSDAY NIGHT. HIGHS THURSDAY WILL BE IN THE 80S...70S IN THE BLACK HILLS. .LONG TERM...FRIDAY THROUGH WEDNESDAY ISSUED AT 218 PM MDT WED AUG 5 2015 PROGRESSIVE FLOW WILL CONTINUE THROUGH THE WEEKEND WITH A STRONGER UPPER LEVEL TROUGH ON TRACK FOR SAT-SUN. HOWEVER...STRONG INDICATIONS ARE IN PLACE FOR SIG LONG WAVE RIDGING OVER CENTRAL NOAM EARLY NEXT WEEK WHICH WOULD SUPPORT A MUCH WARMER PERIOD FOR THE REGION BY THE MIDDLE OF NEXT WEEK. HIGHEST POPS IN THE PERIOD ARE IN THE SAT-SUN PERIOD AS THE CURRENT UPPER LOW OFF THE COAST OF CA EJECTS NE ACROSS THE ROCKIES AND INTO THE REGION. PLENTY OF LL MOISTURE WILL BE IN PLACE WITH INCREASING LARGE SCALE ASCENT AND MONSOON MOISTURE TO SUPPORT SCT SHRA/TS IN THIS PERIOD ESP ACROSS THE NORTHERN ZONES. LINGERING CHANCES FOR PRECIP SUNDAY NIGHT WITH DRY WEATHER EXPECTED EARLY NEXT WEEK...PERHAPS A SLIGHT CHANCE OF A TS OVER THE BLACK HILLS TUES WHEN BETTER MOISTURE RETURNS TO THE AREA AHEAD OF A LEE TROUGH. SOME SEVERE THREAT WILL BE IN PLACE SAT/SUN WITH INCREASING FLOW SUPPORTING DECENT BULK SHEAR /0-6KM/ NUMBERS ABOVE 35 KNOTS...WITH 1-2 KJ/KG OF CAPE OVER THE SE FA. HOWEVER...STILL MUCH UNCERTAINTY PER SYSTEM TRACK/SPEED TO ASCERTAIN A BETTER GRASP ON SEVERE PROBS. AFTER A SEASONAL DAY FRIDAY...COOLER TEMPS ARE ON TRACK FOR THE WEEKEND...WITH A MODEST COOL DOWN EXPECTED SUNDAY.. MUCH WARMER WEATHER ON TRACK FOR TUE AND BEYOND WITH 90S EXPECTED. A FEW 100/S A CERTAINLY NOT OUT OF THE QUESTION...ESP ON THE SD PLAINS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 551 PM MDT WED AUG 5 2015 SCATTERED TSRA WITH GUSTY WINDS WILL MOVE ACROSS THE AREA TONIGHT WITH LOCAL IFR CONDITIONS. ACTIVITY WILL MOVE EAST OF THE AREA BY THURSDAY MORNING. OUTSIDE OF STORMS...VFR CONDITIONS WILL PREVAIL. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...HELGESON SHORT TERM...POJORLIE LONG TERM...JC AVIATION...HELGESON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
553 PM MDT WED AUG 5 2015 .SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT ISSUED AT 218 PM MDT WED AUG 5 2015 UPPER WAVE CONTINUES TO APPROACH THE REGION...AS UPPER LOW CIRCULATES OVER SOUTHWEST CANADA. WEAK SHOWERS ACROSS NORTHEAST WYOMING HAVE BEEN DISSIPATING AS THEY MOVE EASTWARD...WITH JUST SOME CLOUDS PUSHING INTO THE CWA. WITH LIGHT AND VARIABLE WINDS...TEMPS ARE GENERALLY IN THE 80S. SHOWERS AND THUNDERSTORMS STILL EXPECTED TO DEVELOP ALONG A LINE OF FRONTOGENESIS/Q-VECTOR CONVERGENCE ACROSS THE WESTERN CWA AND EXPAND EASTWARD. MODELS ARE HINTING AT AN INITIAL WAVE WITH BEST FORCING JUST NORTHWEST OF THE CWA BRINGING A BAND OF STORMS THROUGH THE NORTHERN HILLS AND NORTHWESTERN SD...WITH A SECONDARY WAVE IMMEDIATELY FOLLOWING WITH SCATTERED SHOWERS/STORMS. HRRR THIS MORNING WAS PRETTY CONSISTENT WITH A SQUALL LINE MOVING ACROSS THE NORTHERN HILLS AND NORTHWEST SD EARLY THIS EVENING...BUT LATER RUNS ARE SHOWING A MORE SCATTERED FORM. MLCAPE IS UNIMPRESSIVE AROUND 750 J/KG ON THE PLAINS WITH 1500 J/KG OVER THE HILLS...BUT SHEAR IS 35-45 KTS SO WOULD NOT RULE OUT A STRONG TO SEVERE STORM. MAIN THREAT WILL BE STRONG WINDS. SURFACE LOW WILL MOVE ACROSS SD THURSDAY. A TIGHT PRESSURE GRADIENT BEHIND THE LOW WILL CREATE SOME BREEZY NORTHWEST WINDS ACROSS THE SD PLAINS AND ALSO BRING IN SOME COOLER AIR TO NORTHWESTERN SD. SHOWERS/THUNDERSTORMS WILL CONTINUE ACROSS NORTHWESTERN/CENTRAL SD DURING THE DAY UNTIL THE WAVE FINALLY TRANSITIONS EASTWARD OUT OF THE REGION. DRY WEATHER IS THEN EXPECTED FOR THURSDAY NIGHT. HIGHS THURSDAY WILL BE IN THE 80S...70S IN THE BLACK HILLS. .LONG TERM...FRIDAY THROUGH WEDNESDAY ISSUED AT 218 PM MDT WED AUG 5 2015 PROGRESSIVE FLOW WILL CONTINUE THROUGH THE WEEKEND WITH A STRONGER UPPER LEVEL TROUGH ON TRACK FOR SAT-SUN. HOWEVER...STRONG INDICATIONS ARE IN PLACE FOR SIG LONG WAVE RIDGING OVER CENTRAL NOAM EARLY NEXT WEEK WHICH WOULD SUPPORT A MUCH WARMER PERIOD FOR THE REGION BY THE MIDDLE OF NEXT WEEK. HIGHEST POPS IN THE PERIOD ARE IN THE SAT-SUN PERIOD AS THE CURRENT UPPER LOW OFF THE COAST OF CA EJECTS NE ACROSS THE ROCKIES AND INTO THE REGION. PLENTY OF LL MOISTURE WILL BE IN PLACE WITH INCREASING LARGE SCALE ASCENT AND MONSOON MOISTURE TO SUPPORT SCT SHRA/TS IN THIS PERIOD ESP ACROSS THE NORTHERN ZONES. LINGERING CHANCES FOR PRECIP SUNDAY NIGHT WITH DRY WEATHER EXPECTED EARLY NEXT WEEK...PERHAPS A SLIGHT CHANCE OF A TS OVER THE BLACK HILLS TUES WHEN BETTER MOISTURE RETURNS TO THE AREA AHEAD OF A LEE TROUGH. SOME SEVERE THREAT WILL BE IN PLACE SAT/SUN WITH INCREASING FLOW SUPPORTING DECENT BULK SHEAR /0-6KM/ NUMBERS ABOVE 35 KNOTS...WITH 1-2 KJ/KG OF CAPE OVER THE SE FA. HOWEVER...STILL MUCH UNCERTAINTY PER SYSTEM TRACK/SPEED TO ASCERTAIN A BETTER GRASP ON SEVERE PROBS. AFTER A SEASONAL DAY FRIDAY...COOLER TEMPS ARE ON TRACK FOR THE WEEKEND...WITH A MODEST COOL DOWN EXPECTED SUNDAY.. MUCH WARMER WEATHER ON TRACK FOR TUE AND BEYOND WITH 90S EXPECTED. A FEW 100/S A CERTAINLY NOT OUT OF THE QUESTION...ESP ON THE SD PLAINS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 551 PM MDT WED AUG 5 2015 SCATTERED TSRA WITH GUSTY WINDS WILL MOVE ACROSS THE AREA TONIGHT WITH LOCAL IFR CONDITIONS. ACTIVITY WILL MOVE EAST OF THE AREA BY THURSDAY MORNING. OUTSIDE OF STORMS...VFR CONDITIONS WILL PREVAIL. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...POJORLIE LONG TERM...JC AVIATION...HELGESON
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
326 PM CDT TUE AUG 4 2015 .DISCUSSION... LOOKS LIKE 1 LAST DAY OF LITTLE OR NO CONVECTION. MODELS DID A GOOD JOB WITH THE MOISTURE ENHANCEMENT TO OUR NORTH WHERE THE STATIONARY BOUNDARY RESIDES. CURRENTLY WE ARE SEEING ISOL TO SCT CONVECTION ACROSS KY. GOING FORWARD...MODELS HINGING ON AN AREA OF MOISTURE ACROSS EASTERN OK. GFS AND HRRR SOLUTIONS CARRY THIS SYSTEM OUR WAY AND ACTUALLY BRING IN SOME CONVECTION ACROSS OUR NW NEAR 12Z. NAM IS DELAYING THE ONSET OF MOISTURE UNTIL TOMORROW NIGHT. FOR THE FCST...WILL LEAN TOWARD A BLEND AND INCLUDE DESCENT POPS FOR WED THROUGH THU. AN APPROACHING SHORTWAVE WILL INTERACT WITH THE SFC TROUGH TO OUR SOUTH...WHICH WILL BE WORKING SLOWLY NORTHWARD THROUGH THU. TOTAL QPF AMOUNTS THROUGH THU NT LOOK AS THOUGH THEY WILL RANGE FROM 1 TO 1 1/2 INCHES NW TO AROUND 1/2 INCH SE. AS FOR CONVECTIVE STRENGTH...THE NAM MODEL LOOKS RATHER POTENT ON THU AS A FRONTAL BOUNDARY IS POSITIONED TO OUR NORTH AND LINEAR OMEGA FIELDS MATCH UP WITH A 40 KT LLJ AND RESPECTABLE CAPES. THE GFS HOWEVER IS FURTHER SOUTH WITH THE BOUNDARY AND THE SITUATION LOOKS UNSTABLE. FUTURE MODELS WILL HOPEFULLY SORT THIS OUT. FOR THE NEAR TERM TEMPS...ITS BEEN QUITE HOT TODAY...HIGHS HAVE REACHED WELL INTO THE 90S. QUITE THE DISCREPANCY WITH THE HIGH TEMP GUIDANCE FOR WEDNESDAY. MET SUGGESTS 92F FOR BNA AND THE MAV SUGGESTS 80F. THIS WILL LARGELY HINGE ON THE DEGREE OF MOISTURE THAT ARRIVES TOMORROW. WILL OPT TO BLEND BUT TREND TOWARD THE GFS AND GO WITH A HIGH OF 84F. THU WILL AGAIN FEATURE BELOW NORMAL HIGH TEMPS AS THE SHORTWAVE MOVES THROUGH. IN THE EXT FCST...THE AFOREMENTIONED SHORTWAVE WILL EXIT AND THE TYPICAL NW FLOW REGIME WILL RESUME. DISTURBANCES WITHIN THE FLOW LOOK HIT/MISS. NO OVERLY APPRECIABLE MOISTURE LEVELS ARE INDICATED. THEREFORE...WILL CONTINUE THE THEME OF LOW POPS FOR THE EXTENDED PERIOD. FOR THE EXT TEMPS...VALUES WILL RETURN INTO THE LOWER 90S FOR HIGHS. LOW LEVEL SOUTHERLY FETCH WILL KEEP HUMID CONDITIONS IN PLACE AND THUS...LOW TEMPS GENERALLY IN THE LOWER 70S. .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 74 84 70 85 / 10 40 60 70 CLARKSVILLE 72 83 69 83 / 20 50 70 70 CROSSVILLE 70 84 67 80 / 10 40 60 80 COLUMBIA 73 87 70 87 / 10 30 60 70 LAWRENCEBURG 72 87 69 87 / 10 40 60 70 WAVERLY 73 84 69 84 / 20 50 70 70 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
338 PM CDT TUE AUG 4 2015 .DISCUSSION... A VERY WEAK FRONTAL BOUNDARY AND A SEA BREEZE MOVED INLAND EARLIER TODAY. A MORE MOIST AIRMASS WAS REFLECTED BY PW/S UP TO AROUND 2.0 INCHES AS SEEN ON THE SPC RAP OUTPUT. IN ADDITION TO THE SURFACE BOUNDARIES...THE NAM12 AND RAP13 BOTH SHOWED WEAK VORTICITY ADVECTION MOVING OVERHEAD OF THE FORECAST AREA. THIS COMBINATION HAS GENERATED ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. AM EXPECTING THE ACTIVITY TO DIMINISH AROUND SUNSET. REGARDING RAIN CHANCES FOR WEDNESDAY...THE MID AND UPPER LEVEL RIDGE IS FORECAST BY THE MODELS TO CONTINUE BUILDING OVERHEAD. EVEN SO...THE NAM12 AND HIGH RESOLUTION MODELS SHOW ISOLATED RAIN CHANCES DURING THE AFTERNOON. SINCE THE MODELS HAVE BEEN CONSISTENT OVER THE PAST COUPLE OF DAYS...DECIDED TO GO WITH A 15 PERCENT RAIN CHANCE AND MENTION ISOLATED SHOWERS AND THUNDERSTORMS POSSIBLE DURING THE AFTERNOON ASSOCIATED WITH THE SEA BREEZE. RAIN CHANCES WILL DIMINISH FOR THE REST OF THIS WEEK AND INTO MONDAY OF NEXT WEEK AS THE UPPER LEVEL RIDGE BUILDS OVER THE STATE. THE MAIN ISSUE THROUGH THE UPCOMING WEEKEND WILL BE THE BUILDING HOT AND HUMID AIRMASS. THE GUIDANCE AND RAW MODEL OUTPUT WERE FORECASTING ACTUAL DAYTIME HIGH TEMPERATURES OVER THE INLAND COUNTIES AS HIGH AS 99 TO 102 IN SOME PLACES WELL INLAND THROUGH SATURDAY. THE HEAT INDEX MAY REACH 103 TO 108 OVER SOME LOCATIONS ON WEDNESDAY AND FRIDAY...AND THEN MAY POSSIBLY EXCEED 108 FRIDAY AND SATURDAY. WILL CONTINUE TO MONITOR THE MODEL TRENDS AS THE WEEK PROGRESSES. 40 && .AVIATION... KEPT MENTION OF PCPN FOR MOST SITES FOR THE REST OF THIS AFTN GIVEN THE TRENDS. MODELS INDICATING THAT THESE HIGH PWS (JUST OVER 2") TO PERSIST THRU TOMORROW AFTN SO WE COULD SEE A REPEAT OF TODAY. BRIEF MVFR CIGS NOTED FOR SOME SITES THIS MORNING. 41 && .MARINE... NOT A LOT OF CHANGES WITH AFTN FCST PACKAGE FOR THE MARINE ZONES AS THE CURRENT WX PATTERN REMAINS IN PLACE. THE LIGHT/MODERATE ONSHORE WINDS WILL PERSIST WITH DIURNAL VARIATIONS. ISO/WIDELY SCT POSSIBLE EARLY TOMORROW GIVEN THE LINGERING DEEPER MOISTURE. 41 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 77 99 77 100 77 / 10 10 10 10 10 HOUSTON (IAH) 78 97 79 98 79 / 10 20 10 10 10 GALVESTON (GLS) 83 92 83 91 83 / 10 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...41
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
123 PM CDT TUE AUG 4 2015 .UPDATE... ANOTHER UPDATE TO TWEAK RAIN CHANCES. SPC WRF WAS ANALYZING 1.8 TO 2 INCH PW/S ACROSS THE I-10 AND SOUTHWARD CORRIDOR. BRIEF HEAVY DOWNPOURS WERE ACCOMPANYING THE SHOWERS AND ISOLATED THUNDERSTORMS. 40 && .PREV DISCUSSION... /ISSUED 1134 AM CDT TUE AUG 4 2015/ UPDATE... ADJUSTED POPS FURTHER NORTHWARD. RADAR AT 1130 AM SHOWED SCATTERED SHOWERS DEVELOPING WEST AND NORTHWEST OF METRO HOUSTON. 40 PREV DISCUSSION... /ISSUED 1016 AM CDT TUE AUG 4 2015/ DISCUSSION... A SURFACE TROUGH EXTENDED ACROSS THE NORTHWESTERN GULF TO NEAR GALVESTON THIS MORNING. RADAR SHOWED THAT SHOWERS WERE TRYING TO DEVELOP ALONG AND SOUTH OF A LINE FROM NEAR WHARTON TO GALVESTON...HOWEVER SUBSIDENCE DUE TO THE UPPER LEVEL RIDGE WAS APPEARING TO KEEP THE COVERAGE VERY ISOLATED. MODEL GUIDANCE VARIED FOR COVERAGE THIS AFTERNOON...FROM ONLY AN ISOLATED SHOWER OR STORM TO MORE SCATTERED COVERAGE. THE 12Z NAM12 CONTINUED ITS TREND OF BRING ISOLATED TO SCATTERED COVERAGE CLOSE TO THE NORTHERN COUNTIES LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS LOOKED TO BE DUE TO THE MODEL SHOWING A STRONGER SHORTWAVE TROUGH ON THE NORTHERN SIDE OF THE RIDGE. FOR NOW...THE CURRENT FORECAST LOOKS ON TRACK. WILL WATCH TRENDS AND UPDATE LATER THIS MORNING OR INTO THE EARLY AFTERNOON IF NECESSARY. 40 PREV DISCUSSION... /ISSUED 558 AM CDT TUE AUG 4 2015/ DISCUSSION... SEE 12Z AVIATION DISCUSSION. AVIATION... MODELS (NAM12/GFS) SENDING A BIT OF A MIXED MESSAGE THIS MORNING AS FCST SOUNDINGS SHOW PW VALUES EXCEEDING 2.10 INCHES AT KIAH THIS AFTN BUT MODEL MASS FIELDS REMAIN BARE. THOUGHT THE RAP INITIALIZED WELL AND HAVE LEANED TOWARD THE RAP TODAY. FEEL SHRA WILL GENERALLY STAY OVER THE SOUTHERN TAF SITES AND IMPACT KGLS...KLBX AND KHOU. VFR CONDS ARE EXPECTED TODAY AND MOST OF TONIGHT WITH SOME BRIEF MVFR CIGS TOWARD SUNRISE WEDNESDAY. 43 PREV DISCUSSION... /ISSUED 408 AM CDT TUE AUG 4 2015/ DISCUSSION... EARLY MORNING WATER VAPOR IMAGERY AND EVENING UPPER AIR ANALYSIS SHOWED A FLATTENED UPPER RIDGE STRETCHING ACROSS THE SOUTHWESTERN CONUS INTO TEXAS... WITH A COMPACT SHORTWAVE TROUGH MOVING ACROSS CO/WY AND AN UPPER LOW OVER THE PACIFIC SPINNING ABOUT 800 MILES OFF THE COAST OF NORTHERN CA. A PLUME OF VERY MOIST AIR /PRECIPITABLE WATER VALUES OF 2.3 TO 2.5 INCHES/ WAS LOCATED OVER WHARTON... JACKSON... AND MATAGORDA COUNTIES PER GOES SOUNDER IMAGERY. A FEW EARLY MORNING SHOWERS HAD ALREADY BEGUN TO DEVELOP AROUND MATAGORDA BAY WITHIN THIS MORE MOIST AIRMASS AND AT LEAST ISOLATED SHOWERS WILL BE POSSIBLE SOUTH OF INTERSTATE 10 THROUGH THE REMAINDER OF THE MORNING. AS SOUTHERLY WINDS INCREASE TODAY... THIS MORE MOIST AIRMASS WILL PUSH FARTHER INLAND. THIS... COMBINED WITH DAYTIME HEATING AND THE SEA BREEZE... WILL KEEP THE CHANCE FOR ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST THIS AFTERNOON AND EVENING MAINLY ALONG AND SOUTH OF A COLUMBUS TO CLEVELAND LINE. CANNOT RULE OUT AN ISOLATED STRONGER WIND GUST WITH THIS ACTIVITY AS DCAPE VALUES APPROACH 1000 J/KG THIS AFTERNOON... BUT BRIEF HEAVY DOWNPOURS APPEAR TO BE THE MOST LIKELY HAZARD GIVEN THE EXTREMELY MOIST ENVIRONMENT. HIGH TEMPERATURES THIS AFTERNOON ARE EXPECTED TO TOP OUT IN THE LOW 90S ALONG THE COAST... WITH MID TO UPPER 90S FARTHER INLAND. HEAT INDEX VALUES MAY APPROACH OR SLIGHTLY EXCEED 105 DEGREES THIS AFTERNOON... BUT WILL CONTINUE TO INCREASE DURING THE WEEK AS AFTERNOON TEMPERATURES RISE. ELEVATED LOW LEVEL MOISTURE WILL PROMOTE A LIMITED COOLDOWN OVERNIGHT AS TEMPERATURES ONLY FALL INTO THE MID 70S TO NEAR 80. THE UPPER RIDGE WILL SHIFT EAST WEDNESDAY AS THE LOW OVER THE PACIFIC APPROACHES THE WEST COAST. HIGH RESOLUTION GUIDANCE BREAKS OUT A FEW SHOWERS FROM COASTAL CONVERGENCE ALONG THE COAST WEDNESDAY MORNING AND AGAIN WEDNESDAY AFTERNOON ALONG THE SEA BREEZE BUT ONLY HIGHLIGHTING THIS ACTIVITY WITH SILENT 10 POPS FOR NOW DUE TO ANTICIPATED LOW COVERAGE. OTHERWISE... ANOTHER HOT DAY EXPECTED WEDNESDAY WITH TEMPERATURES SIMILAR TO TODAY. HEAT INDEX VALUES ARE EXPECTED TO REMAIN BELOW HEAT ADVISORY CRITERIA AGAIN ON WEDNESDAY... BUT HEAT ADVISORY CRITERIA MAY BE MET AS EARLY AS THURSDAY FOR PARTS OF THE AREA. FOR THE REMAINDER OF THE FORECAST... HOT AND DRY IS PROBABLY THE BEST WAY TO DESCRIBE THE SENSIBLE WEATHER PATTERN. THE UPPER RIDGE BUILDING FARTHER EAST WILL ALLOW TEMPERATURES TO RISE INTO THE LOW 100S BY THE BEGINNING OF THE WEEKEND. MEDIUM RANGE GUIDANCE BUILDS THE CENTER OF THE UPPER RIDGE OVER NORTH TEXAS AND INTO THE ARKLATEX BY SATURDAY... WITH THIS FEATURE MAINTAINING CONTROL OVER THE SOUTHERN PLAINS WELL INTO NEXT WEEK. HUFFMAN MARINE... HIGH PRESSURE OVER THE EASTERN GULF WILL PRODUCE A SW-S WIND TODAY. A WEAK BOUNDARY OVER THE GULF WILL SERVE AS A FOCUS FOR SHOWERS AND ISOLATED THUNDERSTORMS OVER THE MARINE ZONES TODAY. THE GRADIENT WILL BEGIN TO TIGHTEN WEDNESDAY AND WEDNESDAY NIGHT AS LOW PRESSURE DEEPENS OVER THE SOUTHERN PLAINS. A LIGHT TO OCCASIONALLY MODERATE ONSHORE FLOW WILL PERSIST THROUGH NEXT WEEKEND. 43 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 99 77 99 77 99 / 20 10 10 10 10 HOUSTON (IAH) 97 78 97 79 98 / 40 10 10 10 10 GALVESTON (GLS) 92 82 92 82 91 / 20 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...41
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1134 AM CDT TUE AUG 4 2015 .UPDATE... ADJUSTED POPS FURTHER NORTHWARD. RADAR AT 1130 AM SHOWED SCATTERED SHOWERS DEVELOPING WEST AND NORTHWEST OF METRO HOUSTON. 40 && .PREV DISCUSSION... /ISSUED 1016 AM CDT TUE AUG 4 2015/ DISCUSSION... A SURFACE TROUGH EXTENDED ACROSS THE NORTHWESTERN GULF TO NEAR GALVESTON THIS MORNING. RADAR SHOWED THAT SHOWERS WERE TRYING TO DEVELOP ALONG AND SOUTH OF A LINE FROM NEAR WHARTON TO GALVESTON...HOWEVER SUBSIDENCE DUE TO THE UPPER LEVEL RIDGE WAS APPEARING TO KEEP THE COVERAGE VERY ISOLATED. MODEL GUIDANCE VARIED FOR COVERAGE THIS AFTERNOON...FROM ONLY AN ISOLATED SHOWER OR STORM TO MORE SCATTERED COVERAGE. THE 12Z NAM12 CONTINUED ITS TREND OF BRING ISOLATED TO SCATTERED COVERAGE CLOSE TO THE NORTHERN COUNTIES LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS LOOKED TO BE DUE TO THE MODEL SHOWING A STRONGER SHORTWAVE TROUGH ON THE NORTHERN SIDE OF THE RIDGE. FOR NOW...THE CURRENT FORECAST LOOKS ON TRACK. WILL WATCH TRENDS AND UPDATE LATER THIS MORNING OR INTO THE EARLY AFTERNOON IF NECESSARY. 40 PREV DISCUSSION... /ISSUED 558 AM CDT TUE AUG 4 2015/ DISCUSSION... SEE 12Z AVIATION DISCUSSION. AVIATION... MODELS (NAM12/GFS) SENDING A BIT OF A MIXED MESSAGE THIS MORNING AS FCST SOUNDINGS SHOW PW VALUES EXCEEDING 2.10 INCHES AT KIAH THIS AFTN BUT MODEL MASS FIELDS REMAIN BARE. THOUGHT THE RAP INITIALIZED WELL AND HAVE LEANED TOWARD THE RAP TODAY. FEEL SHRA WILL GENERALLY STAY OVER THE SOUTHERN TAF SITES AND IMPACT KGLS...KLBX AND KHOU. VFR CONDS ARE EXPECTED TODAY AND MOST OF TONIGHT WITH SOME BRIEF MVFR CIGS TOWARD SUNRISE WEDNESDAY. 43 PREV DISCUSSION... /ISSUED 408 AM CDT TUE AUG 4 2015/ DISCUSSION... EARLY MORNING WATER VAPOR IMAGERY AND EVENING UPPER AIR ANALYSIS SHOWED A FLATTENED UPPER RIDGE STRETCHING ACROSS THE SOUTHWESTERN CONUS INTO TEXAS... WITH A COMPACT SHORTWAVE TROUGH MOVING ACROSS CO/WY AND AN UPPER LOW OVER THE PACIFIC SPINNING ABOUT 800 MILES OFF THE COAST OF NORTHERN CA. A PLUME OF VERY MOIST AIR /PRECIPITABLE WATER VALUES OF 2.3 TO 2.5 INCHES/ WAS LOCATED OVER WHARTON... JACKSON... AND MATAGORDA COUNTIES PER GOES SOUNDER IMAGERY. A FEW EARLY MORNING SHOWERS HAD ALREADY BEGUN TO DEVELOP AROUND MATAGORDA BAY WITHIN THIS MORE MOIST AIRMASS AND AT LEAST ISOLATED SHOWERS WILL BE POSSIBLE SOUTH OF INTERSTATE 10 THROUGH THE REMAINDER OF THE MORNING. AS SOUTHERLY WINDS INCREASE TODAY... THIS MORE MOIST AIRMASS WILL PUSH FARTHER INLAND. THIS... COMBINED WITH DAYTIME HEATING AND THE SEA BREEZE... WILL KEEP THE CHANCE FOR ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST THIS AFTERNOON AND EVENING MAINLY ALONG AND SOUTH OF A COLUMBUS TO CLEVELAND LINE. CANNOT RULE OUT AN ISOLATED STRONGER WIND GUST WITH THIS ACTIVITY AS DCAPE VALUES APPROACH 1000 J/KG THIS AFTERNOON... BUT BRIEF HEAVY DOWNPOURS APPEAR TO BE THE MOST LIKELY HAZARD GIVEN THE EXTREMELY MOIST ENVIRONMENT. HIGH TEMPERATURES THIS AFTERNOON ARE EXPECTED TO TOP OUT IN THE LOW 90S ALONG THE COAST... WITH MID TO UPPER 90S FARTHER INLAND. HEAT INDEX VALUES MAY APPROACH OR SLIGHTLY EXCEED 105 DEGREES THIS AFTERNOON... BUT WILL CONTINUE TO INCREASE DURING THE WEEK AS AFTERNOON TEMPERATURES RISE. ELEVATED LOW LEVEL MOISTURE WILL PROMOTE A LIMITED COOLDOWN OVERNIGHT AS TEMPERATURES ONLY FALL INTO THE MID 70S TO NEAR 80. THE UPPER RIDGE WILL SHIFT EAST WEDNESDAY AS THE LOW OVER THE PACIFIC APPROACHES THE WEST COAST. HIGH RESOLUTION GUIDANCE BREAKS OUT A FEW SHOWERS FROM COASTAL CONVERGENCE ALONG THE COAST WEDNESDAY MORNING AND AGAIN WEDNESDAY AFTERNOON ALONG THE SEA BREEZE BUT ONLY HIGHLIGHTING THIS ACTIVITY WITH SILENT 10 POPS FOR NOW DUE TO ANTICIPATED LOW COVERAGE. OTHERWISE... ANOTHER HOT DAY EXPECTED WEDNESDAY WITH TEMPERATURES SIMILAR TO TODAY. HEAT INDEX VALUES ARE EXPECTED TO REMAIN BELOW HEAT ADVISORY CRITERIA AGAIN ON WEDNESDAY... BUT HEAT ADVISORY CRITERIA MAY BE MET AS EARLY AS THURSDAY FOR PARTS OF THE AREA. FOR THE REMAINDER OF THE FORECAST... HOT AND DRY IS PROBABLY THE BEST WAY TO DESCRIBE THE SENSIBLE WEATHER PATTERN. THE UPPER RIDGE BUILDING FARTHER EAST WILL ALLOW TEMPERATURES TO RISE INTO THE LOW 100S BY THE BEGINNING OF THE WEEKEND. MEDIUM RANGE GUIDANCE BUILDS THE CENTER OF THE UPPER RIDGE OVER NORTH TEXAS AND INTO THE ARKLATEX BY SATURDAY... WITH THIS FEATURE MAINTAINING CONTROL OVER THE SOUTHERN PLAINS WELL INTO NEXT WEEK. HUFFMAN MARINE... HIGH PRESSURE OVER THE EASTERN GULF WILL PRODUCE A SW-S WIND TODAY. A WEAK BOUNDARY OVER THE GULF WILL SERVE AS A FOCUS FOR SHOWERS AND ISOLATED THUNDERSTORMS OVER THE MARINE ZONES TODAY. THE GRADIENT WILL BEGIN TO TIGHTEN WEDNESDAY AND WEDNESDAY NIGHT AS LOW PRESSURE DEEPENS OVER THE SOUTHERN PLAINS. A LIGHT TO OCCASIONALLY MODERATE ONSHORE FLOW WILL PERSIST THROUGH NEXT WEEKEND. 43 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 99 77 99 77 99 / 20 10 10 10 10 HOUSTON (IAH) 97 78 97 79 98 / 40 10 10 10 10 GALVESTON (GLS) 92 82 92 82 91 / 20 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...41
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1016 AM CDT TUE AUG 4 2015 .DISCUSSION... A SURFACE TROUGH EXTENDED ACROSS THE NORTHWESTERN GULF TO NEAR GALVESTON THIS MORNING. RADAR SHOWED THAT SHOWERS WERE TRYING TO DEVELOP ALONG AND SOUTH OF A LINE FROM NEAR WHARTON TO GALVESTON...HOWEVER SUBSIDENCE DUE TO THE UPPER LEVEL RIDGE WAS APPEARING TO KEEP THE COVERAGE VERY ISOLATED. MODEL GUIDANCE VARIED FOR COVERAGE THIS AFTERNOON...FROM ONLY AN ISOLATED SHOWER OR STORM TO MORE SCATTERED COVERAGE. THE 12Z NAM12 CONTINUED ITS TREND OF BRING ISOLATED TO SCATTERED COVERAGE CLOSE TO THE NORTHERN COUNTIES LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS LOOKED TO BE DUE TO THE MODEL SHOWING A STRONGER SHORTWAVE TROUGH ON THE NORTHERN SIDE OF THE RIDGE. FOR NOW...THE CURRENT FORECAST LOOKS ON TRACK. WILL WATCH TRENDS AND UPDATE LATER THIS MORNING OR INTO THE EARLY AFTERNOON IF NECESSARY. 40 && .PREV DISCUSSION... /ISSUED 558 AM CDT TUE AUG 4 2015/ DISCUSSION... SEE 12Z AVIATION DISCUSSION. AVIATION... MODELS (NAM12/GFS) SENDING A BIT OF A MIXED MESSAGE THIS MORNING AS FCST SOUNDINGS SHOW PW VALUES EXCEEDING 2.10 INCHES AT KIAH THIS AFTN BUT MODEL MASS FIELDS REMAIN BARE. THOUGHT THE RAP INITIALIZED WELL AND HAVE LEANED TOWARD THE RAP TODAY. FEEL SHRA WILL GENERALLY STAY OVER THE SOUTHERN TAF SITES AND IMPACT KGLS...KLBX AND KHOU. VFR CONDS ARE EXPECTED TODAY AND MOST OF TONIGHT WITH SOME BRIEF MVFR CIGS TOWARD SUNRISE WEDNESDAY. 43 PREV DISCUSSION... /ISSUED 408 AM CDT TUE AUG 4 2015/ DISCUSSION... EARLY MORNING WATER VAPOR IMAGERY AND EVENING UPPER AIR ANALYSIS SHOWED A FLATTENED UPPER RIDGE STRETCHING ACROSS THE SOUTHWESTERN CONUS INTO TEXAS... WITH A COMPACT SHORTWAVE TROUGH MOVING ACROSS CO/WY AND AN UPPER LOW OVER THE PACIFIC SPINNING ABOUT 800 MILES OFF THE COAST OF NORTHERN CA. A PLUME OF VERY MOIST AIR /PRECIPITABLE WATER VALUES OF 2.3 TO 2.5 INCHES/ WAS LOCATED OVER WHARTON... JACKSON... AND MATAGORDA COUNTIES PER GOES SOUNDER IMAGERY. A FEW EARLY MORNING SHOWERS HAD ALREADY BEGUN TO DEVELOP AROUND MATAGORDA BAY WITHIN THIS MORE MOIST AIRMASS AND AT LEAST ISOLATED SHOWERS WILL BE POSSIBLE SOUTH OF INTERSTATE 10 THROUGH THE REMAINDER OF THE MORNING. AS SOUTHERLY WINDS INCREASE TODAY... THIS MORE MOIST AIRMASS WILL PUSH FARTHER INLAND. THIS... COMBINED WITH DAYTIME HEATING AND THE SEA BREEZE... WILL KEEP THE CHANCE FOR ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST THIS AFTERNOON AND EVENING MAINLY ALONG AND SOUTH OF A COLUMBUS TO CLEVELAND LINE. CANNOT RULE OUT AN ISOLATED STRONGER WIND GUST WITH THIS ACTIVITY AS DCAPE VALUES APPROACH 1000 J/KG THIS AFTERNOON... BUT BRIEF HEAVY DOWNPOURS APPEAR TO BE THE MOST LIKELY HAZARD GIVEN THE EXTREMELY MOIST ENVIRONMENT. HIGH TEMPERATURES THIS AFTERNOON ARE EXPECTED TO TOP OUT IN THE LOW 90S ALONG THE COAST... WITH MID TO UPPER 90S FARTHER INLAND. HEAT INDEX VALUES MAY APPROACH OR SLIGHTLY EXCEED 105 DEGREES THIS AFTERNOON... BUT WILL CONTINUE TO INCREASE DURING THE WEEK AS AFTERNOON TEMPERATURES RISE. ELEVATED LOW LEVEL MOISTURE WILL PROMOTE A LIMITED COOLDOWN OVERNIGHT AS TEMPERATURES ONLY FALL INTO THE MID 70S TO NEAR 80. THE UPPER RIDGE WILL SHIFT EAST WEDNESDAY AS THE LOW OVER THE PACIFIC APPROACHES THE WEST COAST. HIGH RESOLUTION GUIDANCE BREAKS OUT A FEW SHOWERS FROM COASTAL CONVERGENCE ALONG THE COAST WEDNESDAY MORNING AND AGAIN WEDNESDAY AFTERNOON ALONG THE SEA BREEZE BUT ONLY HIGHLIGHTING THIS ACTIVITY WITH SILENT 10 POPS FOR NOW DUE TO ANTICIPATED LOW COVERAGE. OTHERWISE... ANOTHER HOT DAY EXPECTED WEDNESDAY WITH TEMPERATURES SIMILAR TO TODAY. HEAT INDEX VALUES ARE EXPECTED TO REMAIN BELOW HEAT ADVISORY CRITERIA AGAIN ON WEDNESDAY... BUT HEAT ADVISORY CRITERIA MAY BE MET AS EARLY AS THURSDAY FOR PARTS OF THE AREA. FOR THE REMAINDER OF THE FORECAST... HOT AND DRY IS PROBABLY THE BEST WAY TO DESCRIBE THE SENSIBLE WEATHER PATTERN. THE UPPER RIDGE BUILDING FARTHER EAST WILL ALLOW TEMPERATURES TO RISE INTO THE LOW 100S BY THE BEGINNING OF THE WEEKEND. MEDIUM RANGE GUIDANCE BUILDS THE CENTER OF THE UPPER RIDGE OVER NORTH TEXAS AND INTO THE ARKLATEX BY SATURDAY... WITH THIS FEATURE MAINTAINING CONTROL OVER THE SOUTHERN PLAINS WELL INTO NEXT WEEK. HUFFMAN MARINE... HIGH PRESSURE OVER THE EASTERN GULF WILL PRODUCE A SW-S WIND TODAY. A WEAK BOUNDARY OVER THE GULF WILL SERVE AS A FOCUS FOR SHOWERS AND ISOLATED THUNDERSTORMS OVER THE MARINE ZONES TODAY. THE GRADIENT WILL BEGIN TO TIGHTEN WEDNESDAY AND WEDNESDAY NIGHT AS LOW PRESSURE DEEPENS OVER THE SOUTHERN PLAINS. A LIGHT TO OCCASIONALLY MODERATE ONSHORE FLOW WILL PERSIST THROUGH NEXT WEEKEND. 43 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 99 77 99 77 99 / 10 10 10 10 10 HOUSTON (IAH) 97 78 97 79 98 / 20 10 10 10 10 GALVESTON (GLS) 92 82 92 82 91 / 20 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...41
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
558 AM CDT TUE AUG 4 2015 .DISCUSSION... SEE 12Z AVIATION DISCUSSION. && .AVIATION... MODELS (NAM12/GFS) SENDING A BIT OF A MIXED MESSAGE THIS MORNING AS FCST SOUNDINGS SHOW PW VALUES EXCEEDING 2.10 INCHES AT KIAH THIS AFTN BUT MODEL MASS FIELDS REMAIN BARE. THOUGHT THE RAP INITIALIZED WELL AND HAVE LEANED TOWARD THE RAP TODAY. FEEL SHRA WILL GENERALLY STAY OVER THE SOUTHERN TAF SITES AND IMPACT KGLS...KLBX AND KHOU. VFR CONDS ARE EXPECTED TODAY AND MOST OF TONIGHT WITH SOME BRIEF MVFR CIGS TOWARD SUNRISE WEDNESDAY. 43 && .PREV DISCUSSION... /ISSUED 408 AM CDT TUE AUG 4 2015/ DISCUSSION... EARLY MORNING WATER VAPOR IMAGERY AND EVENING UPPER AIR ANALYSIS SHOWED A FLATTENED UPPER RIDGE STRETCHING ACROSS THE SOUTHWESTERN CONUS INTO TEXAS... WITH A COMPACT SHORTWAVE TROUGH MOVING ACROSS CO/WY AND AN UPPER LOW OVER THE PACIFIC SPINNING ABOUT 800 MILES OFF THE COAST OF NORTHERN CA. A PLUME OF VERY MOIST AIR /PRECIPITABLE WATER VALUES OF 2.3 TO 2.5 INCHES/ WAS LOCATED OVER WHARTON... JACKSON... AND MATAGORDA COUNTIES PER GOES SOUNDER IMAGERY. A FEW EARLY MORNING SHOWERS HAD ALREADY BEGUN TO DEVELOP AROUND MATAGORDA BAY WITHIN THIS MORE MOIST AIRMASS AND AT LEAST ISOLATED SHOWERS WILL BE POSSIBLE SOUTH OF INTERSTATE 10 THROUGH THE REMAINDER OF THE MORNING. AS SOUTHERLY WINDS INCREASE TODAY... THIS MORE MOIST AIRMASS WILL PUSH FARTHER INLAND. THIS... COMBINED WITH DAYTIME HEATING AND THE SEA BREEZE... WILL KEEP THE CHANCE FOR ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST THIS AFTERNOON AND EVENING MAINLY ALONG AND SOUTH OF A COLUMBUS TO CLEVELAND LINE. CANNOT RULE OUT AN ISOLATED STRONGER WIND GUST WITH THIS ACTIVITY AS DCAPE VALUES APPROACH 1000 J/KG THIS AFTERNOON... BUT BRIEF HEAVY DOWNPOURS APPEAR TO BE THE MOST LIKELY HAZARD GIVEN THE EXTREMELY MOIST ENVIRONMENT. HIGH TEMPERATURES THIS AFTERNOON ARE EXPECTED TO TOP OUT IN THE LOW 90S ALONG THE COAST... WITH MID TO UPPER 90S FARTHER INLAND. HEAT INDEX VALUES MAY APPROACH OR SLIGHTLY EXCEED 105 DEGREES THIS AFTERNOON... BUT WILL CONTINUE TO INCREASE DURING THE WEEK AS AFTERNOON TEMPERATURES RISE. ELEVATED LOW LEVEL MOISTURE WILL PROMOTE A LIMITED COOLDOWN OVERNIGHT AS TEMPERATURES ONLY FALL INTO THE MID 70S TO NEAR 80. THE UPPER RIDGE WILL SHIFT EAST WEDNESDAY AS THE LOW OVER THE PACIFIC APPROACHES THE WEST COAST. HIGH RESOLUTION GUIDANCE BREAKS OUT A FEW SHOWERS FROM COASTAL CONVERGENCE ALONG THE COAST WEDNESDAY MORNING AND AGAIN WEDNESDAY AFTERNOON ALONG THE SEA BREEZE BUT ONLY HIGHLIGHTING THIS ACTIVITY WITH SILENT 10 POPS FOR NOW DUE TO ANTICIPATED LOW COVERAGE. OTHERWISE... ANOTHER HOT DAY EXPECTED WEDNESDAY WITH TEMPERATURES SIMILAR TO TODAY. HEAT INDEX VALUES ARE EXPECTED TO REMAIN BELOW HEAT ADVISORY CRITERIA AGAIN ON WEDNESDAY... BUT HEAT ADVISORY CRITERIA MAY BE MET AS EARLY AS THURSDAY FOR PARTS OF THE AREA. FOR THE REMAINDER OF THE FORECAST... HOT AND DRY IS PROBABLY THE BEST WAY TO DESCRIBE THE SENSIBLE WEATHER PATTERN. THE UPPER RIDGE BUILDING FARTHER EAST WILL ALLOW TEMPERATURES TO RISE INTO THE LOW 100S BY THE BEGINNING OF THE WEEKEND. MEDIUM RANGE GUIDANCE BUILDS THE CENTER OF THE UPPER RIDGE OVER NORTH TEXAS AND INTO THE ARKLATEX BY SATURDAY... WITH THIS FEATURE MAINTAINING CONTROL OVER THE SOUTHERN PLAINS WELL INTO NEXT WEEK. HUFFMAN MARINE... HIGH PRESSURE OVER THE EASTERN GULF WILL PRODUCE A SW-S WIND TODAY. A WEAK BOUNDARY OVER THE GULF WILL SERVE AS A FOCUS FOR SHOWERS AND ISOLATED THUNDERSTORMS OVER THE MARINE ZONES TODAY. THE GRADIENT WILL BEGIN TO TIGHTEN WEDNESDAY AND WEDNESDAY NIGHT AS LOW PRESSURE DEEPENS OVER THE SOUTHERN PLAINS. A LIGHT TO OCCASIONALLY MODERATE ONSHORE FLOW WILL PERSIST THROUGH NEXT WEEKEND. 43 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 99 77 99 77 99 / 10 10 10 10 10 HOUSTON (IAH) 97 78 97 79 98 / 20 10 10 10 10 GALVESTON (GLS) 92 82 92 82 91 / 20 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1153 AM MDT TUE AUG 4 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT TUE AUG 4 2015 WATER VAPOR IMAGERY SHOWING MONSOON PLUME BEING ADVECTED EAST INTO THE EASTERN CWFA THIS MORNING AHEAD OF AN UPPER LOW CURRENTLY TRACKING INTO SOUTHERN WYOMING NEAR RAWLINS. DRY SLOT MOVING INTO CARBON COUNTY AT THIS TIME. STILL SEEING SOME SHOWERS OVER THE LARAMIE RANGE AT 2 AM THIS MORNING. LATEST MESOWEST OBSERVATIONS SHOWING THAT FAIRLY WIDESPREAD ACCUMULATING RAIN DID FALL ACROSS CARBON AND ALBANY COUNTIES YESTERDAY UNDER THE MOISTURE PLUME. AREAS EAST OF THE LARAMIE RANGE SHOULD SEE THIS PLUME TODAY. DO BELIEVE MOST SEVERE THUNDERSTORM ACTIVITY WILL BE EAST OF THE PANHANDLE TODAY...THOUGH LATEST HRRR SIMULATED RADAR DOES SHOW SOME EARLY DEVELOPMENT LATER THIS MORNING. LATEST NAM SOUNDINGS SHOWING LITTLE TO NO SHEAR AND CAPE VALUES OF 1000-1300J/KG OUT IN THE NORTHERN PANHANDLE THIS AFTERNOON. PRECIPITABLE WATER VALUES NEAR 1.3 INCHES THIS AFTERNOON OUT IN THE PANHANDLE MAKES ME THINK THAT HEAVY RAIN WOULD BE THE PRIMARY HAZARD ASSOCIATED WITH ANY THUNDERSTORMS TODAY. DID INCLUDE HEAVY RAINFALL IN THE NORTHERN PANHANDLE ZONES AND NIOBRARA/NORTHERN GOSHEN COUNTIES IN SOUTHEAST WYOMING. WEAK STEERING FLOW COULD CREATE SLOW MOVING STORMS...SO DAY CREW WOULD NEED TO BE ON THE LOOKOUT FOR POSSIBLE FLASH FLOODING FOR SOME AREAS. UPPER LOW MOVES EAST INTO CENTRAL NEBRASKA AFTER 06Z THIS EVENING WITH MOST SHOWERS AND THUNDERSTORMS COMING TO AN END AFTER THAT TIME. UPPER RIDGE BUILDS BACK OVER THE AREA FOR WEDNESDAY WITH MAINLY DRY CONDITIONS ACROSS THE CWFA. WINDS ON THE INCREASE WEDNESDAY NIGHT INTO THURSDAY AS AN UPPER LOW TRACKS ACROSS NORTHERN MONTANA. GFS 700MB WINDS BEGIN TO INCREASE AFTER 00Z THURSDAY...SETTING THE STAGE FOR POSSIBLE ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS THURSDAY. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 151 AM MDT TUE AUG 4 2015 THE MAIN CONCERN WITH THIS PORTION OF THE FORECAST IS THE POTENTIAL FOR GUSTY WINDS AND WARMER TEMPERATURES AS WE HEAD INTO THURSDAY INTO FRIDAY. THURSDAY-FRIDAY: THE MODELS APPEAR TO BE IN FAIRLY GOOD AGREEMENT IN SHOWING AN UPPER LEVEL WAVE MOVING THROUGH BRITISH COLUMBIA...SASKATCHEWAN AND ALBERTA THURSDAY INTO FRIDAY. THIS WILL FAVOR OUR REGION IN A MORE ZONAL FLOW REGIME WHICH MAY YIELD TO SOME ANOMALOUS 700MB FLOW(~30-35KTS). IF THINGS REALLY MIX OUT ON THURSDAY WE COULD END WITH A GOOD SHOT AT SEEING CRITICAL FIRE WEATHER CONDITIONS. SEE THE FIRE WEATHER DISCUSSION BELOW. IN ADDITION...TEMPERATURES COULD BE QUITE WARM ESPECIALLY IN AREAS EAST OF THE LARAMIE RANGE WHERE DOWNSLOPE FLOW WILL AID. WE DID BUMP UP TEMPERATURES A COUPLE OF DEGREES FROM THE BLENDS TO REFLECT THIS POTENTIAL. THE WIND SPEEDS DO BACK OFF QUITE A BIT ON FRIDAY AS THE UPPER LEVEL RIDGE TRIES TO MAKE A QUICK RETURN. AS A RESULT...TEMPERATURES MAY BE A TAD COOLER WITH POSSIBLY SLIGHTLY HIGHER DEWPOINTS. SATURDAY-MONDAY: THE MODELS ARE IN PRETTY GOOD AGREEMENT IN SHOWING THE SOUTHWEST FLOW DEVELOPING OVER OUR REGION WHICH MAY BRING BACK THE MONSOONAL MOISTURE IN AREAS ALONG AND EAST OF THE LARAMIE RANGE. THE MAIN QUESTION DURING THIS TIMEFRAME WILL BE THE POSITION OF THE UPPER LEVEL TROF IN THE PACIFIC NORTHWEST. IF THE HEIGHT FALLS STAY FOCUSED IN THE PACIFIC NORTHWEST THE MONSOONAL FETCH MAY NOT BE AS GREAT WHICH MAY TEND TO SUPPRESS THE BULK OF THE MOISTURE ACROSS COLORADO AND NEW MEXICO. HOWEVER...IF THE UPPER LEVEL TROF CAN SHIFT A LITTLE FURTHER EAST WE MAY SEE A STRONGER FETCH OF MONSOONAL MOISTURE INTO AREAS EAST OF THE LARAMIE RANGE. FOR NOW...WE WILL PLAY THINGS CONSERVATIVE UNTIL THE PICTURE BECOMES A BIT CLEARER. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1142 AM MDT TUE AUG 4 2015 BRIEF MVFR CONDITIONS ARE POSSIBLE DUE TO THUNDERSTORMS MAINLY IN THE NORTHERN NE PANHANDLE THIS AFTERNOON INTO THE EVENING HOURS. SCATTERED SHOWERS MAY DEVELOP ELSEWHERE WITH MINIMAL IMPACTS TO AVIATION. AFTER 06Z... FOG MAY DEVELOP INTO THE WESTERN NE PANHANDLE ESPECIALLY IN THE PLATTE RIVER VALLEY. THE FOG IS EXPECTED TO LIFT AROUND 15Z. && .FIRE WEATHER... ISSUED AT 300 AM MDT TUE AUG 4 2015 WIDESPREAD WETTING RAINS EXPECTED TODAY AS A LOW PRESSURE SYSTEM TRACKS ACROSS NORTHERN COLORADO. THIS WILL BE ESPECIALLY TRUE FOR FIRE WEATHER ZONES NORTH AND EAST OF THE LARAMIE RANGE TODAY. BEST CHANCES WILL BE 301...302 AND 311 WHERE HEAVY RAINS COULD OCCUR THIS AFTERNOON. A DRIER DAY FOR WEDNESDAY AS THE LOW PRESSURE SYSTEM TRACKS INTO EASTERN NEBRASKA. NEXT CHANCE FOR ELEVATED TO CRITICAL FIRE WEATHER WILL BE WEDNESDAY NIGHT INTO THURSDAY AS LOW PRESSURE TRACKS ACROSS NORTHERN MONTANA AND SOUTHERN ALBERTA CANADA. THIS WILL CREATE STRONG WINDS ACROSS WYOMING WHERE AREAS WEST OF THE LARAMIE RANGE COULD SEE WIND GUSTS IN EXCESS OF 40 MPH AND AFTERNOON HUMIDITIES NEAR CRITICAL. GUSTY AFTERNOON WINDS AND HUMIDITIES NEAR CRITICAL EACH DAY THROUGH FRIDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...GCC LONG TERM...REC AVIATION...CLH/KC FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
546 AM MDT TUE AUG 4 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT TUE AUG 4 2015 WATER VAPOR IMAGERY SHOWING MONSOON PLUME BEING ADVECTED EAST INTO THE EASTERN CWFA THIS MORNING AHEAD OF AN UPPER LOW CURRENTLY TRACKING INTO SOUTHERN WYOMING NEAR RAWLINS. DRY SLOT MOVING INTO CARBON COUNTY AT THIS TIME. STILL SEEING SOME SHOWERS OVER THE LARAMIE RANGE AT 2 AM THIS MORNING. LATEST MESOWEST OBSERVATIONS SHOWING THAT FAIRLY WIDESPREAD ACCUMULATING RAIN DID FALL ACROSS CARBON AND ALBANY COUNTIES YESTERDAY UNDER THE MOISTURE PLUME. AREAS EAST OF THE LARAMIE RANGE SHOULD SEE THIS PLUME TODAY. DO BELIEVE MOST SEVERE THUNDERSTORM ACTIVITY WILL BE EAST OF THE PANHANDLE TODAY...THOUGH LATEST HRRR SIMULATED RADAR DOES SHOW SOME EARLY DEVELOPMENT LATER THIS MORNING. LATEST NAM SOUNDINGS SHOWING LITTLE TO NO SHEAR AND CAPE VALUES OF 1000-1300J/KG OUT IN THE NORTHERN PANHANDLE THIS AFTERNOON. PRECIPITABLE WATER VALUES NEAR 1.3 INCHES THIS AFTERNOON OUT IN THE PANHANDLE MAKES ME THINK THAT HEAVY RAIN WOULD BE THE PRIMARY HAZARD ASSOCIATED WITH ANY THUNDERSTORMS TODAY. DID INCLUDE HEAVY RAINFALL IN THE NORTHERN PANHANDLE ZONES AND NIOBRARA/NORTHERN GOSHEN COUNTIES IN SOUTHEAST WYOMING. WEAK STEERING FLOW COULD CREATE SLOW MOVING STORMS...SO DAY CREW WOULD NEED TO BE ON THE LOOKOUT FOR POSSIBLE FLASH FLOODING FOR SOME AREAS. UPPER LOW MOVES EAST INTO CENTRAL NEBRASKA AFTER 06Z THIS EVENING WITH MOST SHOWERS AND THUNDERSTORMS COMING TO AN END AFTER THAT TIME. UPPER RIDGE BUILDS BACK OVER THE AREA FOR WEDNESDAY WITH MAINLY DRY CONDITIONS ACROSS THE CWFA. WINDS ON THE INCREASE WEDNESDAY NIGHT INTO THURSDAY AS AN UPPER LOW TRACKS ACROSS NORTHERN MONTANA. GFS 700MB WINDS BEGIN TO INCREASE AFTER 00Z THURSDAY...SETTING THE STAGE FOR POSSIBLE ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS THURSDAY. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 151 AM MDT TUE AUG 4 2015 THE MAIN CONCERN WITH THIS PORTION OF THE FORECAST IS THE POTENTIAL FOR GUSTY WINDS AND WARMER TEMPERATURES AS WE HEAD INTO THURSDAY INTO FRIDAY. THURSDAY-FRIDAY: THE MODELS APPEAR TO BE IN FAIRLY GOOD AGREEMENT IN SHOWING AN UPPER LEVEL WAVE MOVING THROUGH BRITISH COLUMBIA...SASKATCHEWAN AND ALBERTA THURSDAY INTO FRIDAY. THIS WILL FAVOR OUR REGION IN A MORE ZONAL FLOW REGIME WHICH MAY YIELD TO SOME ANOMALOUS 700MB FLOW(~30-35KTS). IF THINGS REALLY MIX OUT ON THURSDAY WE COULD END WITH A GOOD SHOT AT SEEING CRITICAL FIRE WEATHER CONDITIONS. SEE THE FIRE WEATHER DISCUSSION BELOW. IN ADDITION...TEMPERATURES COULD BE QUITE WARM ESPECIALLY IN AREAS EAST OF THE LARAMIE RANGE WHERE DOWNSLOPE FLOW WILL AID. WE DID BUMP UP TEMPERATURES A COUPLE OF DEGREES FROM THE BLENDS TO REFLECT THIS POTENTIAL. THE WIND SPEEDS DO BACK OFF QUITE A BIT ON FRIDAY AS THE UPPER LEVEL RIDGE TRIES TO MAKE A QUICK RETURN. AS A RESULT...TEMPERATURES MAY BE A TAD COOLER WITH POSSIBLY SLIGHTLY HIGHER DEWPOINTS. SATURDAY-MONDAY: THE MODELS ARE IN PRETTY GOOD AGREEMENT IN SHOWING THE SOUTHWEST FLOW DEVELOPING OVER OUR REGION WHICH MAY BRING BACK THE MONSOONAL MOISTURE IN AREAS ALONG AND EAST OF THE LARAMIE RANGE. THE MAIN QUESTION DURING THIS TIMEFRAME WILL BE THE POSITION OF THE UPPER LEVEL TROF IN THE PACIFIC NORTHWEST. IF THE HEIGHT FALLS STAY FOCUSED IN THE PACIFIC NORTHWEST THE MONSOONAL FETCH MAY NOT BE AS GREAT WHICH MAY TEND TO SUPPRESS THE BULK OF THE MOISTURE ACROSS COLORADO AND NEW MEXICO. HOWEVER...IF THE UPPER LEVEL TROF CAN SHIFT A LITTLE FURTHER EAST WE MAY SEE A STRONGER FETCH OF MONSOONAL MOISTURE INTO AREAS EAST OF THE LARAMIE RANGE. FOR NOW...WE WILL PLAY THINGS CONSERVATIVE UNTIL THE PICTURE BECOMES A BIT CLEARER. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 531 AM MDT TUE AUG 4 2015 LATEST WATER VAPOR LOOP WAS SHOWING THE CLOSED UPPER LEVEL LOW SPINNING OVER NORTHWEST CARBON COUNTY AND GRADUALLY SHIFTING EAST. THIS FEATURE IS PROGGED TO CONTINUE MOVING SLOWLY EAST TODAY. AHEAD OF THIS WAVE...SOME SCATTERED THUNDERSTORMS MAY DEVELOP OVER AREAS MAINLY NORTH OF INTERSTATE 80. ANY STORMS THAT DO DEVELOP WILL BE SLOW MOVERS. ALONG AND SOUTH OF INTERSTATE 80 GUSTY WEST WINDS ARE EXPECTED WITH GUSTS APPROACHING 35 KTS. OTHERWISE...MVFR CONDITIONS ARE STILL POSSIBLE AT THE KRWL TAF SITE THROUGH MID MORNING UNTIL THE WESTERLY FLOW INCREASES AND HELPS SCOUR OUT THE LOW LEVEL MOISTURE. && .FIRE WEATHER... ISSUED AT 300 AM MDT TUE AUG 4 2015 WIDESPREAD WETTING RAINS EXPECTED TODAY AS A LOW PRESSURE SYSTEM TRACKS ACROSS NORTHERN COLORADO. THIS WILL BE ESPECIALLY TRUE FOR FIRE WEATHER ZONES NORTH AND EAST OF THE LARAMIE RANGE TODAY. BEST CHANCES WILL BE 301...302 AND 311 WHERE HEAVY RAINS COULD OCCUR THIS AFTERNOON. A DRIER DAY FOR WEDNESDAY AS THE LOW PRESSURE SYSTEM TRACKS INTO EASTERN NEBRASKA. NEXT CHANCE FOR ELEVATED TO CRITICAL FIRE WEATHER WILL BE WEDNESDAY NIGHT INTO THURSDAY AS LOW PRESSURE TRACKS ACROSS NORTHERN MONTANA AND SOUTHERN ALBERTA CANADA. THIS WILL CREATE STRONG WINDS ACROSS WYOMING WHERE AREAS WEST OF THE LARAMIE RANGE COULD SEE WIND GUSTS IN EXCESS OF 40 MPH AND AFTERNOON HUMIDITIES NEAR CRITICAL. GUSTY AFTERNOON WINDS AND HUMIDITIES NEAR CRITICAL EACH DAY THROUGH FRIDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...GCC LONG TERM...REC AVIATION...REC FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
300 AM MDT TUE AUG 4 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 300 AM MDT TUE AUG 4 2015 WATER VAPOR IMAGERY SHOWING MONSOON PLUME BEING ADVECTED EAST INTO THE EASTERN CWFA THIS MORNING AHEAD OF AN UPPER LOW CURRENTLY TRACKING INTO SOUTHERN WYOMING NEAR RAWLINS. DRY SLOT MOVING INTO CARBON COUNTY AT THIS TIME. STILL SEEING SOME SHOWERS OVER THE LARAMIE RANGE AT 2 AM THIS MORNING. LATEST MESOWEST OBSERVATIONS SHOWING THAT FAIRLY WIDESPREAD ACCUMULATING RAIN DID FALL ACROSS CARBON AND ALBANY COUNTIES YESTERDAY UNDER THE MOISTURE PLUME. AREAS EAST OF THE LARAMIE RANGE SHOULD SEE THIS PLUME TODAY. DO BELIEVE MOST SEVERE THUNDERSTORM ACTIVITY WILL BE EAST OF THE PANHANDLE TODAY...THOUGH LATEST HRRR SIMULATED RADAR DOES SHOW SOME EARLY DEVELOPMENT LATER THIS MORNING. LATEST NAM SOUNDINGS SHOWING LITTLE TO NO SHEAR AND CAPE VALUES OF 1000-1300J/KG OUT IN THE NORTHERN PANHANDLE THIS AFTERNOON. PRECIPITABLE WATER VALUES NEAR 1.3 INCHES THIS AFTERNOON OUT IN THE PANHANDLE MAKES ME THINK THAT HEAVY RAIN WOULD BE THE PRIMARY HAZARD ASSOCIATED WITH ANY THUNDERSTORMS TODAY. DID INCLUDE HEAVY RAINFALL IN THE NORTHERN PANHANDLE ZONES AND NIOBRARA/NORTHERN GOSHEN COUNTIES IN SOUTHEAST WYOMING. WEAK STEERING FLOW COULD CREATE SLOW MOVING STORMS...SO DAY CREW WOULD NEED TO BE ON THE LOOKOUT FOR POSSIBLE FLASH FLOODING FOR SOME AREAS. UPPER LOW MOVES EAST INTO CENTRAL NEBRASKA AFTER 06Z THIS EVENING WITH MOST SHOWERS AND THUNDERSTORMS COMING TO AN END AFTER THAT TIME. UPPER RIDGE BUILDS BACK OVER THE AREA FOR WEDNESDAY WITH MAINLY DRY CONDITIONS ACROSS THE CWFA. WINDS ON THE INCREASE WEDNESDAY NIGHT INTO THURSDAY AS AN UPPER LOW TRACKS ACROSS NORTHERN MONTANA. GFS 700MB WINDS BEGIN TO INCREASE AFTER 00Z THURSDAY...SETTING THE STAGE FOR POSSIBLE ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS THURSDAY. .LONG TERM...(THURSDAY THROUGH MONDAY) ISSUED AT 151 AM MDT TUE AUG 4 2015 THE MAIN CONCERN WITH THIS PORTION OF THE FORECAST IS THE POTENTIAL FOR GUSTY WINDS AND WARMER TEMPERATURES AS WE HEAD INTO THURSDAY INTO FRIDAY. THURSDAY-FRIDAY: THE MODELS APPEAR TO BE IN FAIRLY GOOD AGREEMENT IN SHOWING AN UPPER LEVEL WAVE MOVING THROUGH BRITISH COLUMBIA...SASKATCHEWAN AND ALBERTA THURSDAY INTO FRIDAY. THIS WILL FAVOR OUR REGION IN A MORE ZONAL FLOW REGIME WHICH MAY YIELD TO SOME ANOMALOUS 700MB FLOW(~30-35KTS). IF THINGS REALLY MIX OUT ON THURSDAY WE COULD END WITH A GOOD SHOT AT SEEING CRITICAL FIRE WEATHER CONDITIONS. SEE THE FIRE WEATHER DISCUSSION BELOW. IN ADDITION...TEMPERATURES COULD BE QUITE WARM ESPECIALLY IN AREAS EAST OF THE LARAMIE RANGE WHERE DOWNSLOPE FLOW WILL AID. WE DID BUMP UP TEMPERATURES A COUPLE OF DEGREES FROM THE BLENDS TO REFLECT THIS POTENTIAL. THE WIND SPEEDS DO BACK OFF QUITE A BIT ON FRIDAY AS THE UPPER LEVEL RIDGE TRIES TO MAKE A QUICK RETURN. AS A RESULT...TEMPERATURES MAY BE A TAD COOLER WITH POSSIBLY SLIGHTLY HIGHER DEWPOINTS. SATURDAY-MONDAY: THE MODELS ARE IN PRETTY GOOD AGREEMENT IN SHOWING THE SOUTHWEST FLOW DEVELOPING OVER OUR REGION WHICH MAY BRING BACK THE MONSOONAL MOISTURE IN AREAS ALONG AND EAST OF THE LARAMIE RANGE. THE MAIN QUESTION DURING THIS TIMEFRAME WILL BE THE POSITION OF THE UPPER LEVEL TROF IN THE PACIFIC NORTHWEST. IF THE HEIGHT FALLS STAY FOCUSED IN THE PACIFIC NORTHWEST THE MONSOONAL FETCH MAY NOT BE AS GREAT WHICH MAY TEND TO SUPPRESS THE BULK OF THE MOISTURE ACROSS COLORADO AND NEW MEXICO. HOWEVER...IF THE UPPER LEVEL TROF CAN SHIFT A LITTLE FURTHER EAST WE MAY SEE A STRONGER FETCH OF MONSOONAL MOISTURE INTO AREAS EAST OF THE LARAMIE RANGE. FOR NOW...WE WILL PLAY THINGS CONSERVATIVE UNTIL THE PICTURE BECOMES A BIT CLEARER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1137 PM MDT MON AUG 3 2015 THE MAIN CONCERN WITH THIS PORTION OF THE FORECAST IS THE TIMING OF WHEN THE CLOSED LOW WILL SHIFT EAST OF THE REGION. LATEST RADAR LOOP WAS SHOWING THE SHOWERS ROTATING THROUGH CENTRAL WYOMING. THIS SHOULD PERSIST THROUGH MUCH OF THE NIGHT AND MAY AFFECT THE RWL TAF SITE. THE REMAINDER OF THE TAF SITES MAY SEE SOME A FEW SPRINKLES...BUT THINGS SHOULD REMAIN MOSTLY DRY. VFR CONDITIONS SHOULD BE THE RULE...BUT THERE IS A SMALL CHANCE THAT MVFR CONDITIONS COULD BRIEFLY AFFECT RWL. AS THIS UPPER LEVEL LOW SHIFTS EAST TODAY...GUSTY WEST WINDS MAY KICK IN ACROSS THE SOUTHERN END OF THE STATE WITH RWL...LAR AND CYS POSSIBLY RECEIVING GUSTS UP TO 35KTS. && .FIRE WEATHER... ISSUED AT 300 AM MDT TUE AUG 4 2015 WIDESPREAD WETTING RAINS EXPECTED TODAY AS A LOW PRESSURE SYSTEM TRACKS ACROSS NORTHERN COLORADO. THIS WILL BE ESPECIALLY TRUE FOR FIRE WEATHER ZONES NORTH AND EAST OF THE LARAMIE RANGE TODAY. BEST CHANCES WILL BE 301...302 AND 311 WHERE HEAVY RAINS COULD OCCUR THIS AFTERNOON. A DRIER DAY FOR WEDNESDAY AS THE LOW PRESSURE SYSTEM TRACKS INTO EASTERN NEBRASKA. NEXT CHANCE FOR ELEVATED TO CRITICAL FIRE WEATHER WILL BE WEDNESDAY NIGHT INTO THURSDAY AS LOW PRESSURE TRACKS ACROSS NORTHERN MONTANA AND SOUTHERN ALBERTA CANADA. THIS WILL CREATE STRONG WINDS ACROSS WYOMING WHERE AREAS WEST OF THE LARAMIE RANGE COULD SEE WIND GUSTS IN EXCESS OF 40 MPH AND AFTERNOON HUMIDITIES NEAR CRITICAL. GUSTY AFTERNOON WINDS AND HUMIDITIES NEAR CRITICAL EACH DAY THROUGH FRIDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...GCC LONG TERM...REC AVIATION...REC FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS LINCOLN IL
330 AM CDT THU AUG 6 2015 .SHORT TERM...(TODAY) ISSUED AT 330 AM CDT THU AUG 6 2015 RAIN WILL BE SOUTHEAST OF I-72 THIS MORNING AND CONTINUE TO MOVE EAST THROUGH THE DAY. MOST OF THE AREA SHOULD BE RAIN-FREE BY AFTERNOON...THOUGH PCPN COULD LINGER IN THE EXTREME SOUTHEAST EARLY AFTERNOON. SATELLITE LOOP SHOWS RELATIVELY COLD TOPS OVER PARTS OF ILLINOIS SO WILL KEEP A CHANCE OF ISOLATED THUNDERSTORMS IN THE FORECAST FOR TODAY. RIDGING SHOULD MOVE INTO THE AREA FROM THE NORTHWEST THIS AFTERNOON...WHICH SHOULD REDUCE SOME OF THE CLOUDS IN THAT AREA. HOWEVER...MOST OF THE AREA SHOULD BE CLOUDY THROUGH THE DAY. WINDS SHOULD BE NORTHEAST THROUGH THE PERIOD WITH THE STRONGEST WINDS BEING IN THE EAST AT AROUND 10MPH. HIGH TEMPS WILL BE SIMILAR TO WEDNESDAY...BUT THE COOLEST TEMPS WILL BE IN THE EAST AND SOUTHEAST WHERE THE PCPN AND CLOUDS LINGER THE LONGEST. LOOKING FOR HIGHS IN THE UPPER 70S IN THE EAST AND SOUTHEAST...WITH LOWER 80S IN THE WEST/NORTHWEST. && .LONG TERM...(TONIGHT THROUGH WEDNESDAY) ISSUED AT 330 AM CDT THU AUG 6 2015 DRY CONDITIONS GENERALLY EXPECTED ACROSS CENTRAL AND SOUTHEAST IL TONIGHT THROUGH SATURDAY. THE EXCEPTION WILL BE SLIGHT CHANCES FROM GALESBURG NW FRIDAY MORNING AND NW OF THE IL RIVER SATURDAY. WEAK SURFACE HIGH PRESSURE RIDGE SETTLES EAST OVER IL TONIGHT BRINGING MOSTLY CLEAR TO PARTLY CLOUDY SKIES. COULD BE SOME PATCHY SHALLOW GROUND FOG LATE TONIGHT BUT KEPT OUT OF FORECAST FOR NOW SINCE FEEL THIS WILL BE FAIRLY ISOLATED IS IT OCCURS. LOWS TONIGHT IN THE LOWER 60S WITH SOME UPPER 50S FROM CHAMPAIGN NE. LOW PRESSURE OVER THE WESTERN DAKOTAS AND EASTERN MT TO TRACK EASTWARD INTO MN BY 18Z/FRI AND HAVE SOME SHORT WAVES AHEAD OF IT INTO WI AND NORTHERN HALF OF IL. THIS COULD BRING ISOLATED CONVECTION TO FAR NORTHERN CWA FRIDAY MORNING WITH BETTER CHANCES NORTH OF I-80 ON FRIDAY. HIGHS FRIDAY MOSTLY 82-84F WITH DEWPOINTS IN THE 60S. 00Z MODELS SHOW A STRONGER MCS TO MOVE OUT OF NE/IA INTO CENTRAL/NORTHERN IL LATE SAT AND MORE LIKELY SAT NIGHT. HAVE SLIGHT CHANCES OF SHOWERS/THUNDERSTORMS NW OF IL RIVER SAT AND THEN LIKELY POPS SAT NIGHT NW OF IL RIVER WHILE SLIGHT POPS FAR SE IL LATE SAT NIGHT. SPC HAS MARGINAL RISK OF SEVERE STORMS LATE SAT AFTERNOON AND SAT NIGHT OVER CENTRAL IL. HIGHS SAT 83-85 WITH DEWPOINTS IN UPPER 60S TO NEAR 70F. HAVE 40-50% CHANCE OF CONVECTION SUNDAY ESPECIALLY IN THE MORNING FROM LINGERING MCS ACTIVITY. HIGHS SUNDAY IN THE LOW TO MID 80S WITH DEWPOINTS 68-73F. A COLD FRONT TO PUSH SOUTHWARD ACROSS CENTRAL IL MONDAY AFTERNOON AND INTO SOUTHEAST IL MONDAY NIGHT. GFS IS SLOWER WITH FRONTAL PASSAGE THAN ECMWF MODEL...BUT BOTH MODELS HAVE TRENDED SLOWER WITH FRONT FROM THEIR RUNS 24 HOURS AGO. CARRIED CHANCE OF SHOWERS/THUDNERSTORMS MONDAY AND 20-30% CHANCES MONDAY NIGHT ESPECIALLY DURING MONDAY EVENING. HIGHS MONDAY IN LOW TO MID 80S WITH WARMEST READINGS SE OF I-70 WHERE UPPER 80S POSSIBLE. EXTENDED MODELS SHOW A STRONG UPPER LEVEL LOW OVER NORTHEAST U.S. BY MIDDLE OF NEXT WEEK WHILE LARGE UPPER LEVEL RIDGE OVER TEXAS INTO CO. SURFACE RIDGE DRIFTING SE ACROSS MIDWEST TUE-THU AND BRINGING DRY AND LESS HUMID AIR INTO IL WITH DEWPOINTS IN THE 60S TUE AND UPPER 50S/LOWER 60S WED/THU. HIGHS GENERALLY IN THE UPPER 70S AND LOWER 80S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1105 PM CDT WED AUG 5 2015 FORECAST CONCERN CONTINUES TO REVOLVE AROUND COVERAGE OF SHOWERS OVERNIGHT AND THE AFFECT ON CIGS. BAND OF RAIN SHOWERS CONTINUES TO ROTATE NORTH-NORTHWEST AROUND A WEAK SURFACE WAVE ACROSS SE MISSOURI INTO FAR SOUTHWEST ILLINOIS. MOST SHORT TERM MODELS HAVE COME AROUND WITH THE IDEA OF THE PRECIP SHIFTING TO OR JUST SOUTH OF A RUSHVILLE TO BLOOMINGTON LINE LATER TONIGHT INTO THURSDAY MORNING. HRRR MODEL INDICATING A BAND OF MVFR AND LOCAL IFR CIGS TO APPROACH A SPI TO CMI LINE AFTER 07Z WITH FORECAST SOUNDINGS SUGGESTING MUCH MORE MOISTURE BELOW 850 MB THAN WHAT WE SAW EARLIER THIS EVENING. THE SURFACE WAVE WILL SHIFT OFF TO OUR EAST BY 18Z TAKING ANY RAIN THREAT AWAY FROM THE TAF SITES. MAY SEE SOME LOWER VFR CIGS LINGER INTO THE EARLY AFTERNOON ACROSS KDEC AND KCMI AS THE SYSTEM DEPARTS BUT IT APPEARS WE SHOULD SEE A DECREASE IN CLOUD COVER FROM NORTHWEST TO SOUTHEAST DURING THE AFTERNOON IN THE WAKE OF THE WEAK STORM SYSTEM. SURFACE WINDS WILL BE EAST TO NORTHEAST AT 7 TO 12 KTS TONIGHT AND NORTHEAST WINDS WILL INCREASE TO BETWEEN 12 AND 17 KTS ON THUR...ESPECIALLY AT KDEC...KBMI AND KCMI. WE MAY EVEN SEE A FEW GUSTS TO AROUND 22 KTS AT TIMES THRU MID AFTERNOON BEFORE WINDS START TO DIMINISH TOWARDS SUNSET. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...AUTEN LONG TERM...07 AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1110 PM CDT WED AUG 5 2015 .UPDATE... ISSUED AT 835 PM CDT WED AUG 5 2015 FRONTAL BOUNDARY STRETCHING FROM SOUTHEAST MISSOURI THROUGH SOUTHERN ILLINOIS CONTINUES TO BE THE FOCUS FOR SHOWERS AND THUNDERSTORMS THIS EVENING AS AN MCV FROM AFTERNOON CONVECTION WAS EDGING SLOWLY EAST ACROSS SOUTHEAST MISSOURI. THIS FEATURE IS EXPECTED TO PUSH OVER SOUTHERN IL LATE TONIGHT INTO THURSDAY MORNING BRINGING MORE WIDESPREAD RAIN AND THUNDERSTORMS TO ROUGHLY AREAS ALONG AND SOUTH OF A SPRINGFIELD TO CHAMPAIGN LINE WITH THE MORE CONCENTRATED QPF/HEAVIER RAINFALL OVER FAR SOUTHEAST IL. THE SMALL BAND OF SHOWERS AND ISOLATED STORMS THAT MOVED MAINLY ALONG AND SOUTH OF A JACKSONVILLE TO SPRINGFIELD LINE DUMPED SOME FAIRLY SIGNIFICANT RAINFALL IN A NARROW BAND FROM WAVERLY WEST TO JUST SOUTH OF WINCHESTER WHERE 1 TO 2 INCHES WAS ESTIMATED FROM LATE THIS AFTERNOON INTO EARLY THIS EVENING. AS THE MCV EDGES SLOWLY INTO SOUTHERN IL WE SHOULD SEE A BETTER SURFACE REFLECTION DEVELOP LATER TONIGHT WHICH SHOULD ENHANCE THE LOW LEVEL CONVERGENCE ALONG AND TO THE NORTHEAST OF THE SURFACE LOW TRACK. THE LAST SEVERAL RUNS OF THE RAPID REFRESH MODEL HAS BEEN SUGGESTING THE PRECIP SHOULD START TO REORGANIZE FURTHER SOUTH CLOSER TO THE SURFACE WAVE AND MCV. SPC MESOANALYSIS SHOWING PRECIPITABLE WATER VALUES OF 2.1 INCHES OVER OUR FAR SOUTH/SE COUNTIES WITH FORECAST SOUNDINGS IN THESE AREAS SHOWING VERY LITTLE WIND FLOW ALOFT SO ANY SHOWERS THAT ORGANIZE CLOSE TO THE SURFACE WAVE AND STALLED FRONTAL BOUNDARY WILL BE VERY EFFICIENT RAIN PRODUCERS WITH SOME OF THE DETERMINISTIC MODELS SUGGESTING 1 TO 2 INCHES POSSIBLE OVER PARTS OF SOUTHEAST IL BY THURSDAY MORNING. WITH SUCH WEAK STEERING WINDS FORECAST INTO THURSDAY MORNING...IT APPEARS THE SLOWER SOLUTION WITH RESPECT TO THE SYSTEM EXITING OUR SOUTHEAST COUNTIES IS LOOKING MORE REASONABLE. HIGHEST POPS WILL BE SOUTH OF I-72 TONIGHT WITH PROGRESSIVELY LOWER POPS AS YOU HEAD NORTH. HAVE ALREADY SENT OUT AN UPDATED SET OF ZONE FORECASTS TO BETTER REFLECT THE ONGONG RAIN ACROSS THE WEST EARLY THIS EVENING AND THE SHOWERS ASSOCIATED WITH THE SLOW MOVING MCV AND SURFACE WAVE OVER SOUTHEAST ILLINOIS OVERNIGHT. NO ADDITIONAL UPDATES ARE NEEDED AT THIS TIME...BUT WILL BE WATCHING FOR THIS SECONDARY DEVELOPMENT OF SHOWERS OVER SOUTHEAST AND SOUTH CENTRAL ILLINOIS THIS EVENING TO SEE IF WE NEED TO ADJUST OUR POPS FURTHER NORTH. LATEST IR SATELLITE INDICATES SOME COOLING CLOUD TOPS STARTING TO DEVELOP JUST AHEAD OF THE MCV BUT AT THE SAME TIME WE HAVE NOTICED AN INCREASE IN DEEP CONVECTION ALONG AN OUTFLOW BOUNDARY FROM EARLIER CONVECTION STARTING TO FLARE UP FROM CENTRAL OKLAHOMA EAST THROUGH NORTHEAST ARKANSAS. IF THAT AREA BECOMES BETTER ORGANIZED...IT MAY EFFECTIVELY KEEP THE BETTER MOISTURE TRANSPORT FURTHER SOUTH...RESULTING IN THE HIGHER QPF VALUES STAYING JUST SOUTH OF OUR AREA. && .SHORT TERM...(TONIGHT) ISSUED AT 255 PM CDT WED AUG 5 2015 RATHER DIFFUSE WEATHER PATTERN OVER MUCH OF THE MIDWEST. HIGH PRESSURE RIDGE IS OVER THE WESTERN HALF OF THE COUNTRY...WITH AN MCS MAKING ITS WAY ACROSS THE MID MISSISSIPPI RIVER VALLEY. GENERAL CONSENSUS OF THE MODELS HAVE BEEN TRENDING PRECIP ALONG A QUASI BOUNDARY ACROSS THE SOUTHERN TIER OF THE STATE...ALTHOUGH THERE HAS BEEN SOME QUESTION AS TO WHERE THIS PARTICULAR FEATURE WILL SET UP. SHORT TERM MODELS HAVE BEEN ENHANCING THAT ACTIVITY AS THE MCV FROM THE ACTIVITY IN CENTRAL MO MAKES ITS WAY TO THE EAST. WITH THE MODELS TRENDING FURTHER SOUTH, HAVE SOME CONCERNS AS TO GOING TOO FAR NORTH WITH THE HIGHER PRECIPITATION CHANCES. WITH PRECIPITATION ABSENT IN THE NORTHERN HALF OF THE CWA, AND POTENTIALLY FURTHER SOUTH, THE MODELS HAVE OVERDONE SOME OF THE BOUNDARY LAYER MOISTURE. HAVE DROPPED THE DEWPOINTS A FEW DEGREES TO COUNTER THIS NORTH OF I- 72. .LONG TERM...(THURSDAY THROUGH WEDNESDAY) ISSUED AT 255 PM CDT WED AUG 5 2015 SHOWER/STORM CHANCES MAY LINGER TO START THE DAY, MAINLY ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA, UNTIL A WAVE MOVING OUT OF THE CENTRAL PLAINS PUSHES EAST OF THE AREA. HOWEVER, AT THIS POINT, THE BULK OF THE UPSTREAM PRECIPITATION IS TIED TO A MCV MOVING ACROSS MISSOURI. IF THIS TREND CONTINUES, MOST OF THURSDAY WILL WIND UP BEING DRY. BEHIND THIS INITIAL SYSTEM, DRY WEATHER HAD BEEN ANTICIPATED UNTIL AT LEAST SATURDAY NIGHT/SUNDAY AS UPPER LEVEL RIDGING WAS PROGGED TO BUILD INTO THE AREA. HOWEVER, MODELS ARE SUGGESTING THAT A STRONGER WAVE MAY TRACK DOWN THE BACK SIDE OF THE RIDGE THURSDAY NIGHT INTO FRIDAY NIGHT, POSSIBLY WITH AN ACCOMPANYING RISK OF SHOWERS/STORMS. THE BEST CHANCES WITH THIS FEATURE APPEAR TO BE THURSDAY NIGHT UPSTREAM ACROSS THE MIDWEST WITH A DECENT LOW LEVEL JET FOCUSED INTO THE AREA. THE DIURNAL WEAKENING OF THIS JET, COUPLED WITH THE SHEARING OUT OF THE WAVE, SHOULD KEEP RAIN CHANCES ON THE LOW SIDE LOCALLY. UPSTREAM MCS DEVELOPMENT MAY OCCUR SATURDAY NIGHT, ALTHOUGH GUIDANCE IS FAR FROM UNANIMOUS IN THE DEVELOPMENT OR WHERE IT MAY TRACK, POSSIBLY PUSHING ACROSS THE FORECAST AREA LATER SATURDAY NIGHT INTO SUNDAY. THEN, BEHIND THIS POTENTIAL MCS, THE NEXT MAJOR WAVE/FRONTAL BOUNDARY AND CHANCE FOR ORGANIZED CONVECTION IS EXPECTED FOR SUNDAY NIGHT INTO MONDAY. DRY WEATHER IS LIKELY BEHIND THIS SYSTEM TO FINISH OUT THE FORECAST PERIOD. NEAR NORMAL TEMPERATURES ARE EXPECTED THROUGH THE PERIOD, WITH HIGHS IN THE 80S AND LOWS IN THE 60S. THERE WILL BE A GRADUAL INCREASE IN HUMIDITY AHEAD OF THE SUNDAY NIGHT/MONDAY FRONT, WITH LESS HUMID CONDITIONS LIKELY IN ITS WAKE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1105 PM CDT WED AUG 5 2015 FORECAST CONCERN CONTINUES TO REVOLVE AROUND COVERAGE OF SHOWERS OVERNIGHT AND THE AFFECT ON CIGS. BAND OF RAIN SHOWERS CONTINUES TO ROTATE NORTH-NORTHWEST AROUND A WEAK SURFACE WAVE ACROSS SE MISSOURI INTO FAR SOUTHWEST ILLINOIS. MOST SHORT TERM MODELS HAVE COME AROUND WITH THE IDEA OF THE PRECIP SHIFTING TO OR JUST SOUTH OF A RUSHVILLE TO BLOOMINGTON LINE LATER TONIGHT INTO THURSDAY MORNING. HRRR MODEL INDICATING A BAND OF MVFR AND LOCAL IFR CIGS TO APPROACH A SPI TO CMI LINE AFTER 07Z WITH FORECAST SOUNDINGS SUGGESTING MUCH MORE MOISTURE BELOW 850 MB THAN WHAT WE SAW EARLIER THIS EVENING. THE SURFACE WAVE WILL SHIFT OFF TO OUR EAST BY 18Z TAKING ANY RAIN THREAT AWAY FROM THE TAF SITES. MAY SEE SOME LOWER VFR CIGS LINGER INTO THE EARLY AFTERNOON ACROSS KDEC AND KCMI AS THE SYSTEM DEPARTS BUT IT APPEARS WE SHOULD SEE A DECREASE IN CLOUD COVER FROM NORTHWEST TO SOUTHEAST DURING THE AFTERNOON IN THE WAKE OF THE WEAK STORM SYSTEM. SURFACE WINDS WILL BE EAST TO NORTHEAST AT 7 TO 12 KTS TONIGHT AND NORTHEAST WINDS WILL INCREASE TO BETWEEN 12 AND 17 KTS ON THUR...ESPECIALLY AT KDEC...KBMI AND KCMI. WE MAY EVEN SEE A FEW GUSTS TO AROUND 22 KTS AT TIMES THRU MID AFTERNOON BEFORE WINDS START TO DIMINISH TOWARDS SUNSET. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SMITH SHORT TERM...HJS LONG TERM...BAK AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
214 AM MDT THU AUG 6 2015 .UPDATE... ISSUED AT 1006 PM MDT WED AUG 5 2015 SMALL THREAT FOR OVERNIGHT CONVECTION WILL CONTINUE ALONG H7 THERMAL RIDGE AS PERSISTENT WAA AND WEAK INSTABILITY PRESENT THROUGH THE EARLY MORNING HOURS. FAIRLY LARGE T-TD SPREADS IN THIS LAYER KEEP CONFIDENCE IN POTENTIAL INSTABILITY BEING REALIZED LOW. OTHERWISE WITH DRYLINE HAVING RETREATED TO THE WEST OF THE AREA HUMID AIRMASS BACK IN PLACE ACROSS THE ENTIRE CWA. STILL A LARGE DEGREE OF SPREAD WITH POTENTIAL FOG FORECASTS WITH ENSEMBLE GUIDANCE REMAINING FAIRLY LOW ON POTENTIAL FOR LOW VISIBILITIES. THAT BEING SAID...WITH CONVERGENCE ALONG SFC-H85 TROUGH SLOWLY ADVANCING TO THE EAST OVERNIGHT AND AFOREMENTIONED NEARLY SATURATED LOW LEVEL AIRMASS EXPECT AREA OF STRATUS TO DEVELOP ACROSS CWA AND SLOWLY ADVANCE TO THE EAST. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 238 PM MDT WED AUG 5 2015 FORECAST CONCERNS WILL BE LOW CHANCE OF THUNDERSTORMS IN THE NORTHWEST CORNER THROUGH THE MIDDLE OF THE NIGHT...THE EXTENT OF THE FOG LATER TONIGHT INTO TOMORROW MORNING...AND ANOTHER CHANCE OF THUNDERSTORMS ON THURSDAY. SATELLITE SHOWING MODELS INITIALLY WELL AT MID AND UPPER LEVELS. THE SREF WAS DOING A LITTLE BETTER THAN THE GFS AND RAP ON THE SURFACE WIND AND PRESSURE FIELD. THE GFS AND CANADIAN WERE DOING A LITTLE BETTER THAN THE SREF AND NAM ON THE LOW LEVEL THERMAL FIELD. TONIGHT...A SURFACE BOUNDARY HAS SET UP ALONG THE WESTERN END OF THE AREA WITH SOME CUMULUS DEVELOPMENT. THAT DEVELOPMENT SHOULD CONTINUE WITH LITTLE TO NO CAP. HOWEVER...THERE IS MUCH AT MID TO UPPER LEVELS UNTIL THE MID EVENING INTO THE OVERNIGHT. A SHORTWAVE TROUGH STARTS MOVING THROUGH IN THE LATER HALF OF THE NIGHT AND THERE ALSO LOOKS TO BE SOME WEAK JET LIFT AFFECTING THE NORTHWEST CORNER THROUGH THE MIDDLE OF TONIGHT. INITIALLY THE NAM IS THE MOST AGGRESSIVE IN PRODUCING THUNDERSTORMS LATER THIS AFTERNOON INTO THE OVERNIGHT HOURS. NOW THE RAP AND HRRR ARE SUPPORTING SOME ISOLATED DEVELOPMENT IN THE AREA OF CONVERGENCE THAT IS GOING ON RIGHT NOW. THIS AREA THEN SHIFTS TO THE NORTH AND EAST THROUGH THE NIGHT. LIFT AND WARM AIR ADVECTION ALOFT INCREASE A GREAT DEAL IN THE EASTERN PORTION OF THE AREA DURING THE LAST HALF OF THE NIGHT. MODELS WOULD INDICATE A STRONG CAP ALOFT BUT MORE THAN ONE PIECE OF GUIDANCE IS INDICATING SOME LIGHT QPF. AM A LITTLE CONCERNED ABOUT THIS ACTIVITY. IF THE LIFT BREAKS THE CAP...THE INSTABILITY AND PWS ARE RATHER IMPRESSIVE. WOULD NOT BE SURPRISED TO HAVE SOME STRONG STORMS WITH SOME HEAVY RAINFALL. THURSDAY...THE NAM AND OTHER HIGH RESOLUTION GUIDANCE DEVELOPS PRECIPITATION OVER THE CENTRAL AND EASTERN PORTION OF THE AREA EARLY IN THE DAY. THIS MATCHES WELL WITH THE INSTABILITY AND SHORTWAVE TROUGH MOVING THROUGH SO WILL CONTINUE THE SLIGHT CHANCE POPS THROUGH THE MORNING. WILL BE POTENTIAL FOR STRONG STORMS AND HEAVY RAINFALL. SOME FOG AND ESPECIALLY STRATUS WILL BE AROUND THROUGH THE MORNING. THIS WILL BE IN ADVANCE OF A BOUNDARY MOVING THROUGH. MODELS BRING THIS BOUNDARY THROUGH DURING THE LATE MORNING AND AFTERNOON. MOST OF THE MODEL OUTPUT WOULD INDICATE THAT NOT MUCH COOLING WILL OCCUR WITH THIS SURFACE TROUGH/WEAK FRONT. THIS DOES MAKE SENSE CONSIDERING THE WESTERLY FLOW ALOFT AND STRONG RIDGE TO OUR SOUTH. SO THE HIGH TEMPERATURE FORECAST WILL BE A LITTLE TRICKY DUE TO THE VARIABLE NATURE OF THE CLOUD COVER...SOME PRECIPITATION POSSIBLE...AND THE BOUNDARY TIMING. SO WENT COOLER IN THE EAST WHERE THE CLOUD COVER LASTS LONGER AND THE 850 MB TEMPERATURES ARE THE COOLEST. HOTTER TEMPERATURES WILL BE IN THE SOUTH AND WEST IT DOES APPEAR. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 213 AM MDT THU AUG 6 2015 THE LONG TERM FORECAST PERIOD WILL ONCE AGAIN BE DOMINATED BY AN UPPER LEVEL RIDGE THAT SETS UP OVER THE SOUTH CENTRAL PORTION OF THE CONUS STARTING SUNDAY. THE RIDGE WILL RETROGRADE WESTWARD AND BECOME A HIGH AMPLITUDE MERIDIONAL PATTERN MONDAY AND WILL LAST FOR THE REST OF THE FORECAST PERIOD. MOST OF THE JET STREAM ACTIVITY AND VORTICITY AREAS WILL REMAIN WELL OUTSIDE OF THE HIGH PLAINS REGION. AT THE SURFACE...ECMWF AND GFS MODELS INDICATE A STATIONARY FRONTAL BOUNDARY IN PLACE JUST TO THE SOUTH OF THE TRI STATE AREA ON SUNDAY. BECAUSE OF THE SURFACE BOUNDARY WILL BE IN THE VICINITY OF THE ENTIRE FORECAST AREA...THERE WILL BE SOME CHANCES FOR RAIN SHOWERS AND THUNDERSTORMS SUNDAY AND MONDAY. AS OF RIGHT NOW THOUGH...IT WOULD NOT BE SURPRISING IF MOST OF THE STORM ACTIVITY REMAINED TO THE SOUTH ALONG THE BEST AREAS OF SURFACE WIND CONVERGENCE. IF THE BOUNDARY REMAINS TO THE SOUTH...HIGH TEMPERATURES WILL BE SOMEWHAT COOLER THAN AVERAGE IN THE MID TO UPPER 80S WITH NORTH TO NORTHEASTERLY WINDS. IF THE BOUNDARY ENDS UP SHIFTING NORTHWARD...SOUTHERLY WINDS WILL BRING MOIST DEW POINTS IN THE UPPER 50S TO MIDDLE 60S AND BETTER STORM CHANCES. REGARDLESS OF THE FRONTAL POSITION...ECMWF AND GFS MODEL SOUNDINGS SHOW PLENTY OF MOISTURE AVAILABLE THROUGHOUT THE PROFILE WITH PRECIPITABLE WATER VALUES BETWEEN 1 AND 1.5 INCHES...WHICH IS BETWEEN THE 75TH AND 99TH PERCENTILE FOR AUGUST. WITH CAPE PRESENT IN THE PROFILES BETWEEN 1000 AND 2000 J/KG AND A LACK OF GOOD BULK SHEAR VALUES...EXPECTING ANY POSSIBILITY OF THUNDERSTORMS TO BE MARGINALLY STRONG TO SEVERE WITH THE MAIN POTENTIAL BEING HEAVY RAINFALL FOR SUNDAY AND MONDAY. ONCE THE RIDGE ALOFT AMPLIFIES FOR TUESDAY AND WEDNESDAY...THE UPPER LEVEL HIGH WILL BE VERY NEARLY POSITIONED RIGHT OVER NORTHWEST KANSAS. AS A RESULT...NOT EXPECTING MUCH FOR PRECIPITATION OR CLOUD COVER. CONSENSUS FORECAST WAS INDICATING SOME CHANCES FOR PRECIPITATION...BUT DECIDED TO REMOVE PRECIPITATION CHANCES DUE TO THE SYNOPTIC SET UP. TEMPERATURES WILL WARM BACK TO NEAR NORMAL IN THE UPPER 80S TO LOWER 90S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1135 PM MDT WED AUG 5 2015 CONFIDENCE IN A LOW STRATUS SET UP OVER FOG HAS INCREASED WITH 2-5 HOUR PERIOD OF MFVR/IFR CONDITIONS EXPECTED AT GLD AROUND 12Z. POTENTIAL FOR FOG REMAINS AT MCK...WITH STRATUS EXPECTED LATER IN THE MORNING AND LIKELY WITH HEIGHTS A BIT HIGHER THAN AT GLD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JRM SHORT TERM...BULLER LONG TERM...MK AVIATION...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1136 PM MDT WED AUG 5 2015 .UPDATE... ISSUED AT 1006 PM MDT WED AUG 5 2015 SMALL THREAT FOR OVERNIGHT CONVECTION WILL CONTINUE ALONG H7 THERMAL RIDGE AS PERSISTENT WAA AND WEAK INSTABILITY PRESENT THROUGH THE EARLY MORNING HOURS. FAIRLY LARGE T-TD SPREADS IN THIS LAYER KEEP CONFIDENCE IN POTENTIAL INSTABILITY BEING REALIZED LOW. OTHERWISE WITH DRYLINE HAVING RETREATED TO THE WEST OF THE AREA HUMID AIRMASS BACK IN PLACE ACROSS THE ENTIRE CWA. STILL A LARGE DEGREE OF SPREAD WITH POTENTIAL FOG FORECASTS WITH ENSEMBLE GUIDANCE REMAINING FAIRLY LOW ON POTENTIAL FOR LOW VISIBILITIES. THAT BEING SAID...WITH CONVERGENCE ALONG SFC-H85 TROUGH SLOWLY ADVANCING TO THE EAST OVERNIGHT AND AFOREMENTIONED NEARLY SATURATED LOW LEVEL AIRMASS EXPECT AREA OF STRATUS TO DEVELOP ACROSS CWA AND SLOWLY ADVANCE TO THE EAST. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 238 PM MDT WED AUG 5 2015 FORECAST CONCERNS WILL BE LOW CHANCE OF THUNDERSTORMS IN THE NORTHWEST CORNER THROUGH THE MIDDLE OF THE NIGHT...THE EXTENT OF THE FOG LATER TONIGHT INTO TOMORROW MORNING...AND ANOTHER CHANCE OF THUNDERSTORMS ON THURSDAY. SATELLITE SHOWING MODELS INITIALLY WELL AT MID AND UPPER LEVELS. THE SREF WAS DOING A LITTLE BETTER THAN THE GFS AND RAP ON THE SURFACE WIND AND PRESSURE FIELD. THE GFS AND CANADIAN WERE DOING A LITTLE BETTER THAN THE SREF AND NAM ON THE LOW LEVEL THERMAL FIELD. TONIGHT...A SURFACE BOUNDARY HAS SET UP ALONG THE WESTERN END OF THE AREA WITH SOME CUMULUS DEVELOPMENT. THAT DEVELOPMENT SHOULD CONTINUE WITH LITTLE TO NO CAP. HOWEVER...THERE IS MUCH AT MID TO UPPER LEVELS UNTIL THE MID EVENING INTO THE OVERNIGHT. A SHORTWAVE TROUGH STARTS MOVING THROUGH IN THE LATER HALF OF THE NIGHT AND THERE ALSO LOOKS TO BE SOME WEAK JET LIFT AFFECTING THE NORTHWEST CORNER THROUGH THE MIDDLE OF TONIGHT. INITIALLY THE NAM IS THE MOST AGGRESSIVE IN PRODUCING THUNDERSTORMS LATER THIS AFTERNOON INTO THE OVERNIGHT HOURS. NOW THE RAP AND HRRR ARE SUPPORTING SOME ISOLATED DEVELOPMENT IN THE AREA OF CONVERGENCE THAT IS GOING ON RIGHT NOW. THIS AREA THEN SHIFTS TO THE NORTH AND EAST THROUGH THE NIGHT. LIFT AND WARM AIR ADVECTION ALOFT INCREASE A GREAT DEAL IN THE EASTERN PORTION OF THE AREA DURING THE LAST HALF OF THE NIGHT. MODELS WOULD INDICATE A STRONG CAP ALOFT BUT MORE THAN ONE PIECE OF GUIDANCE IS INDICATING SOME LIGHT QPF. AM A LITTLE CONCERNED ABOUT THIS ACTIVITY. IF THE LIFT BREAKS THE CAP...THE INSTABILITY AND PWS ARE RATHER IMPRESSIVE. WOULD NOT BE SURPRISED TO HAVE SOME STRONG STORMS WITH SOME HEAVY RAINFALL. THURSDAY...THE NAM AND OTHER HIGH RESOLUTION GUIDANCE DEVELOPS PRECIPITATION OVER THE CENTRAL AND EASTERN PORTION OF THE AREA EARLY IN THE DAY. THIS MATCHES WELL WITH THE INSTABILITY AND SHORTWAVE TROUGH MOVING THROUGH SO WILL CONTINUE THE SLIGHT CHANCE POPS THROUGH THE MORNING. WILL BE POTENTIAL FOR STRONG STORMS AND HEAVY RAINFALL. SOME FOG AND ESPECIALLY STRATUS WILL BE AROUND THROUGH THE MORNING. THIS WILL BE IN ADVANCE OF A BOUNDARY MOVING THROUGH. MODELS BRING THIS BOUNDARY THROUGH DURING THE LATE MORNING AND AFTERNOON. MOST OF THE MODEL OUTPUT WOULD INDICATE THAT NOT MUCH COOLING WILL OCCUR WITH THIS SURFACE TROUGH/WEAK FRONT. THIS DOES MAKE SENSE CONSIDERING THE WESTERLY FLOW ALOFT AND STRONG RIDGE TO OUR SOUTH. SO THE HIGH TEMPERATURE FORECAST WILL BE A LITTLE TRICKY DUE TO THE VARIABLE NATURE OF THE CLOUD COVER...SOME PRECIPITATION POSSIBLE...AND THE BOUNDARY TIMING. SO WENT COOLER IN THE EAST WHERE THE CLOUD COVER LASTS LONGER AND THE 850 MB TEMPERATURES ARE THE COOLEST. HOTTER TEMPERATURES WILL BE IN THE SOUTH AND WEST IT DOES APPEAR. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 116 PM MDT WED AUG 5 2015 RIDGE AXIS BUILDS OVER THE HIGH PLAINS THURSDAY NIGHT RESULTING IN DRY CONDITIONS. NEXT SHORTWAVE TROUGH WILL TOP THE RIDGE FRIDAY AFTERNOON AND EVENING BRINGING A GOOD CHANCE FOR THUNDERSTORMS. WHILE SHEAR/INSTABILITY PARAMETERS ARE NOT OVERWHELMING...THEY ARE PROBABLY SUFFICIENT FOR ANOTHER ROUND OF SEVERE WEATHER WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. NAM PRECIPITABLE WATER VALUES INCREASE TO 1-1.5 INCHES BY 00Z/SAT AND STORM MOTIONS WILL BE NORTHEAST AT AROUND 20KTS...NEITHER PARAMETER REALLY SUGGESTING WIDESPREAD HEAVY RAINFALL THOUGH THERE WILL CERTAINLY BE SOME LOCAL DELUGES...ESPECIALLY NEAR RIGHT MOVING SUPERCELLS WHERE STORM MOTIONS WILL BE MUCH SLOWER. THE PATTERN DOESN`T CHANGE MUCH ON SATURDAY WITH A BROAD SOUTHWESTERLY FLOW ALOFT AND EMBEDDED WEAK SHORTWAVE TROUGH BRINGING ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME SEVERE WITH SUFFICIENT SHEAR/INSTABILITY FORECAST ONCE AGAIN. WILD CARD WILL BE LOCATION OF SURFACE BOUNDARIES WHICH MAY BE INFLUENCED BY PREVIOUS DAYS CONVECTION AND WILL BE HARD TO PIN DOWN AT THIS TIME...BUT MAY PROVE TO BE PIVOTAL FOR CONVECTIVE INITIATION. SUNDAY THROUGH WEDNESDAY THE RIDGE IS FORECAST TO BUILD SHARPLY NORTHWARD WITH THE RIDGE AXIS BY WEDNESDAY CENTERED OVER THE HIGH PLAINS FROM CANADA TO THE TEXAS PANHANDLE. FOR THIS REASON AM SOMEWHAT SKEPTICAL OF PRECIPITATION CHANCES IN THE GLOBAL MODELS AND THE DERIVED BLENDS USED TO INITIATE THE EXTENDED THE PERIODS. NONETHELESS...SURFACE PROGS SHOW A CONSISTENT MOIST SOUTHEASTERLY FLOW INTO THE REGION WITH RESULTANT INSTABILITY EACH DAY. SO THE ATMOSPHERE WILL BE PRIMED FOR LIFT AND ANY MINOR DISTURBANCE WHICH MAY MAKES ITS WAY THROUGH THE RIDGE MAY BE ENOUGH FOR CONVECTION TO DEVELOP. HOWEVER DEEP LAYER SHEAR WILL BE RATHER LOW UNDER THE RIDGE SO SEVERE THREAT SHOULD BE LIMITED. TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1135 PM MDT WED AUG 5 2015 CONFIDENCE IN A LOW STRATUS SET UP OVER FOG HAS INCREASED WITH 2-5 HOUR PERIOD OF MFVR/IFR CONDITIONS EXPECTED AT GLD AROUND 12Z. POTENTIAL FOR FOG REMAINS AT MCK...WITH STRATUS EXPECTED LATER IN THE MORNING AND LIKELY WITH HEIGHTS A BIT HIGHER THAN AT GLD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JRM SHORT TERM...BULLER LONG TERM...024 AVIATION...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1026 PM MDT WED AUG 5 2015 .UPDATE... ISSUED AT 1006 PM MDT WED AUG 5 2015 SMALL THREAT FOR OVERNIGHT CONVECTION WILL CONTINUE ALONG H7 THERMAL RIDGE AS PERSISTENT WAA AND WEAK INSTABILITY PRESENT THROUGH THE EARLY MORNING HOURS. FAIRLY LARGE T-TD SPREADS IN THIS LAYER KEEP CONFIDENCE IN POTENTIAL INSTABILITY BEING REALIZED LOW. OTHERWISE WITH DRYLINE HAVING RETREATED TO THE WEST OF THE AREA HUMID AIRMASS BACK IN PLACE ACROSS THE ENTIRE CWA. STILL A LARGE DEGREE OF SPREAD WITH POTENTIAL FOG FORECASTS WITH ENSEMBLE GUIDANCE REMAINING FAIRLY LOW ON POTENTIAL FOR LOW VISIBILITIES. THAT BEING SAID...WITH CONVERGENCE ALONG SFC-H85 TROUGH SLOWLY ADVANCING TO THE EAST OVERNIGHT AND AFOREMENTIONED NEARLY SATURATED LOW LEVEL AIRMASS EXPECT AREA OF STRATUS TO DEVELOP ACROSS CWA AND SLOWLY ADVANCE TO THE EAST. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 238 PM MDT WED AUG 5 2015 FORECAST CONCERNS WILL BE LOW CHANCE OF THUNDERSTORMS IN THE NORTHWEST CORNER THROUGH THE MIDDLE OF THE NIGHT...THE EXTENT OF THE FOG LATER TONIGHT INTO TOMORROW MORNING...AND ANOTHER CHANCE OF THUNDERSTORMS ON THURSDAY. SATELLITE SHOWING MODELS INITIALLY WELL AT MID AND UPPER LEVELS. THE SREF WAS DOING A LITTLE BETTER THAN THE GFS AND RAP ON THE SURFACE WIND AND PRESSURE FIELD. THE GFS AND CANADIAN WERE DOING A LITTLE BETTER THAN THE SREF AND NAM ON THE LOW LEVEL THERMAL FIELD. TONIGHT...A SURFACE BOUNDARY HAS SET UP ALONG THE WESTERN END OF THE AREA WITH SOME CUMULUS DEVELOPMENT. THAT DEVELOPMENT SHOULD CONTINUE WITH LITTLE TO NO CAP. HOWEVER...THERE IS MUCH AT MID TO UPPER LEVELS UNTIL THE MID EVENING INTO THE OVERNIGHT. A SHORTWAVE TROUGH STARTS MOVING THROUGH IN THE LATER HALF OF THE NIGHT AND THERE ALSO LOOKS TO BE SOME WEAK JET LIFT AFFECTING THE NORTHWEST CORNER THROUGH THE MIDDLE OF TONIGHT. INITIALLY THE NAM IS THE MOST AGGRESSIVE IN PRODUCING THUNDERSTORMS LATER THIS AFTERNOON INTO THE OVERNIGHT HOURS. NOW THE RAP AND HRRR ARE SUPPORTING SOME ISOLATED DEVELOPMENT IN THE AREA OF CONVERGENCE THAT IS GOING ON RIGHT NOW. THIS AREA THEN SHIFTS TO THE NORTH AND EAST THROUGH THE NIGHT. LIFT AND WARM AIR ADVECTION ALOFT INCREASE A GREAT DEAL IN THE EASTERN PORTION OF THE AREA DURING THE LAST HALF OF THE NIGHT. MODELS WOULD INDICATE A STRONG CAP ALOFT BUT MORE THAN ONE PIECE OF GUIDANCE IS INDICATING SOME LIGHT QPF. AM A LITTLE CONCERNED ABOUT THIS ACTIVITY. IF THE LIFT BREAKS THE CAP...THE INSTABILITY AND PWS ARE RATHER IMPRESSIVE. WOULD NOT BE SURPRISED TO HAVE SOME STRONG STORMS WITH SOME HEAVY RAINFALL. THURSDAY...THE NAM AND OTHER HIGH RESOLUTION GUIDANCE DEVELOPS PRECIPITATION OVER THE CENTRAL AND EASTERN PORTION OF THE AREA EARLY IN THE DAY. THIS MATCHES WELL WITH THE INSTABILITY AND SHORTWAVE TROUGH MOVING THROUGH SO WILL CONTINUE THE SLIGHT CHANCE POPS THROUGH THE MORNING. WILL BE POTENTIAL FOR STRONG STORMS AND HEAVY RAINFALL. SOME FOG AND ESPECIALLY STRATUS WILL BE AROUND THROUGH THE MORNING. THIS WILL BE IN ADVANCE OF A BOUNDARY MOVING THROUGH. MODELS BRING THIS BOUNDARY THROUGH DURING THE LATE MORNING AND AFTERNOON. MOST OF THE MODEL OUTPUT WOULD INDICATE THAT NOT MUCH COOLING WILL OCCUR WITH THIS SURFACE TROUGH/WEAK FRONT. THIS DOES MAKE SENSE CONSIDERING THE WESTERLY FLOW ALOFT AND STRONG RIDGE TO OUR SOUTH. SO THE HIGH TEMPERATURE FORECAST WILL BE A LITTLE TRICKY DUE TO THE VARIABLE NATURE OF THE CLOUD COVER...SOME PRECIPITATION POSSIBLE...AND THE BOUNDARY TIMING. SO WENT COOLER IN THE EAST WHERE THE CLOUD COVER LASTS LONGER AND THE 850 MB TEMPERATURES ARE THE COOLEST. HOTTER TEMPERATURES WILL BE IN THE SOUTH AND WEST IT DOES APPEAR. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 116 PM MDT WED AUG 5 2015 RIDGE AXIS BUILDS OVER THE HIGH PLAINS THURSDAY NIGHT RESULTING IN DRY CONDITIONS. NEXT SHORTWAVE TROUGH WILL TOP THE RIDGE FRIDAY AFTERNOON AND EVENING BRINGING A GOOD CHANCE FOR THUNDERSTORMS. WHILE SHEAR/INSTABILITY PARAMETERS ARE NOT OVERWHELMING...THEY ARE PROBABLY SUFFICIENT FOR ANOTHER ROUND OF SEVERE WEATHER WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. NAM PRECIPITABLE WATER VALUES INCREASE TO 1-1.5 INCHES BY 00Z/SAT AND STORM MOTIONS WILL BE NORTHEAST AT AROUND 20KTS...NEITHER PARAMETER REALLY SUGGESTING WIDESPREAD HEAVY RAINFALL THOUGH THERE WILL CERTAINLY BE SOME LOCAL DELUGES...ESPECIALLY NEAR RIGHT MOVING SUPERCELLS WHERE STORM MOTIONS WILL BE MUCH SLOWER. THE PATTERN DOESN`T CHANGE MUCH ON SATURDAY WITH A BROAD SOUTHWESTERLY FLOW ALOFT AND EMBEDDED WEAK SHORTWAVE TROUGH BRINGING ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME SEVERE WITH SUFFICIENT SHEAR/INSTABILITY FORECAST ONCE AGAIN. WILD CARD WILL BE LOCATION OF SURFACE BOUNDARIES WHICH MAY BE INFLUENCED BY PREVIOUS DAYS CONVECTION AND WILL BE HARD TO PIN DOWN AT THIS TIME...BUT MAY PROVE TO BE PIVOTAL FOR CONVECTIVE INITIATION. SUNDAY THROUGH WEDNESDAY THE RIDGE IS FORECAST TO BUILD SHARPLY NORTHWARD WITH THE RIDGE AXIS BY WEDNESDAY CENTERED OVER THE HIGH PLAINS FROM CANADA TO THE TEXAS PANHANDLE. FOR THIS REASON AM SOMEWHAT SKEPTICAL OF PRECIPITATION CHANCES IN THE GLOBAL MODELS AND THE DERIVED BLENDS USED TO INITIATE THE EXTENDED THE PERIODS. NONETHELESS...SURFACE PROGS SHOW A CONSISTENT MOIST SOUTHEASTERLY FLOW INTO THE REGION WITH RESULTANT INSTABILITY EACH DAY. SO THE ATMOSPHERE WILL BE PRIMED FOR LIFT AND ANY MINOR DISTURBANCE WHICH MAY MAKES ITS WAY THROUGH THE RIDGE MAY BE ENOUGH FOR CONVECTION TO DEVELOP. HOWEVER DEEP LAYER SHEAR WILL BE RATHER LOW UNDER THE RIDGE SO SEVERE THREAT SHOULD BE LIMITED. TEMPERATURES WILL BE NEAR NORMAL THROUGH THE PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 543 PM MDT WED AUG 5 2015 UPDATED AT 1020 PM MDT... CONFIDENCE IN A LOW STRATUS SET UP OVER FOG HAS INCREASED WITH 2-5 HOUR PERIOD OF MFVR/IFR CONDITIONS EXPECTED AT GLD AROUND 12Z. POTENTIAL FOR FOG REMAINS AT MCK...WITH STRATUS EXPECTED LATER IN THE MORNING AND LIKELY WITH HEIGHTS A BIT HIGHER THAN AT GLD. PREVIOUS DISCUSSION... A FEW THUNDERSTORMS ARE POSSIBLE ACROSS NORTHWEST PORTIONS OF THE AREA BUT DO NOT ANTICIPATE MUCH OF AN IMPACT ON TERMINAL FORECASTS BUT MAY HAVE A STORM OR TWO NEAR MCK VICINITY LATER TONIGHT. FOG POTENTIAL AGAIN A CONCERN AND THINK MOST LIKELY AREA WILL BE EAST OF A TO TRIBUNE LINE WITH HIGHEST CHANCES AT MCK. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JRM SHORT TERM...BULLER LONG TERM...024 AVIATION...JRM
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1158 PM CDT WED AUG 5 2015 .UPDATE... ISSUED AT 1158 PM CDT WED AUG 5 2015 UPDATED THE AVIATION DISCUSSION FOR THE 06Z TAF ISSUANCE. && UPDATE ISSUED AT 1030 PM CDT WED AUG 5 2015 MINOR UPDATE TO ADDRESS MOVEMENT OF WEAKENED MCV/OPEN SHORTWAVE CIRCULATION TO THE NORTH AND THE GRADIENT LIFT ALONG AND SOUTH OF THE IMPRESSED STATIONARY FRONTAL BOUNDARY ALONG THE SOUTHERN BORDER OF THE WFO PAH FORECAST AREA. THE HRRR SUGGESTS THAT THE MEAN LIFT AND ROTATION AROUND THE CIRCULATION IN SOUTHERN ILLINOIS IS A LITTLE FURTHER SOUTH THAN ADVERTISED BY THE 12KM NAM-WRF. HOWEVER...AS THE NEXT WAVE ROTATES INTO SOUTHEAST MISSOURI AFTER MIDNIGHT, ENOUGH FORCING WILL BE IN PLACE TO LIFT AND CONDENSE MOISTURE NORTHEAST ACROSS THE STATIONARY BOUNDARY INTO WEST KENTUCKY...WHILE MAINTAINING LIFT ALONG AND NORTHEAST OF THE MAIN CIRCULATION CENTER IN SOUTHERN ILLINOIS. WITH THAT SCENARIO IN PLACE...WILL LEAVE FLASH FLOOD WATCH IN PLACE FOR THE WFO PAH FORECAST AREA AT THIS TIME. THERE MAY BE AN OPPORTUNITY AFTER MIDNIGHT TO DROP NORTHERN SECTIONS OF SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS BEFORE 7 AM CDT...AS THE EVOLUTION OF THE LAST MINOR IMPULSE OVER SOUTHEAST MISSOURI TAKES PLACE ALONG AND SHORTLY AFTER MIDNIGHT. OTHERWISE...ONLY MINOR ADJUSTMENTS MADE TO REFLECT SHORT TERM PRECIPITATION AND SENSIBLE WEATHER ELEMENTS VARIATIONS. UPDATE ISSUED AT 635 PM CDT WED AUG 5 2015 && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 312 PM CDT WED AUG 5 2015 LINE OF CONVECTION MOVING INTO SOUTHEAST MISSOURI WILL PUSH THROUGH MUCH OF SOUTHEAST MISSOURI LATE THIS AFTERNOON AND THEN LIKELY PIVOT TO MORE OF A NORTHWEST TO SOUTHEAST BAND OVER SOUTHERN ILLINOIS AND WEST KENTUCKY THIS EVENING. NOTICING NEW SCATTERED CONVECTION TO THE NORTHEAST AND SOUTHWEST OF KSTL AS THE PRIMARY CIRCULATION TAKES SHAPE OVER CENTRAL MISSOURI. THIS MAY BE THE BEGINNING OF A DEFORMATION ZONE ABOUT THE CIRCULATION. THE DISTURBANCE WILL BE SLOW TO PUSH EAST THROUGH THE REGION TONIGHT...SO FIGURE THERE WILL STILL BE SIGNIFICANT RAINFALL...ESPECIALLY EAST OF THE MISSISSIPPI RIVER. SO WILL KEEP THE FLASH FLOOD WATCH GOING FOR THE ENTIRE ARE AT THIS TIME...BUT IT MAY BE MORE OF AN AREAL FLOOD EVENT...AND NOT SO MUCH OF A FLASH FLOOD EVENT. PLAN ON CANCELING AT LEAST THE WESTERN 4 COUNTIES IN MISSOURI ONCE THE LINE HAS PASSED THERE IN AN HOUR OR TWO. FIGURE THAT THE PRECIPITATION WILL MOSTLY BE DONE BEFORE 18Z THURSDAY IN THE EAST...BUT WILL KEEP A CHANCE IN THE SOUTHEAST THROUGH THE AFTERNOON JUST TO GIVE IT A WIDE BERTH. STILL HAVE A CHANCE OF CONVECTION MAINLY OVER SOUTHEAST MISSOURI LATE THURSDAY NIGHT AND FRIDAY...AS ANOTHER DISTURBANCE PUSHES SOUTHEAST THROUGH THE AREA. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 312 PM CDT WED AUG 5 2015 UNLIKE MOST LATE SUMMER SITUATION...THE NORMALLY DOMINANT SOUTHEAST U.S. RIDGE IS NOTICEABLY ABSENT THIS SUMMER. ALTHOUGH CPC SUGGESTS CURRENT EL NINO REGIME IMPACT IS MINIMAL ACROSS THE U.S. ...WE CONTINUE TO BE LOCKED INTO A MEAN NORTHWEST FLOW PATTERN WITH THE MEAN CENTER OF THE BROAD 500 MB HIGH PRESSURE CENTER WAFFLING BETWEEN TEXAS AND THE FOUR CORNERS AREA OF THE DESERT SOUTHWEST. MODEL INITIALIZATION...FROM A SATELLITE PERSPECTIVE...GIVES CREDENCE TO THE DETERMINISTIC AND ENSEMBLE GFS SOLUTIONS FOR THE MEDIUM RANGE TIME PERIOD. FROM OTHER SENSIBLE WEATHER PERSPECTIVES THE DETERMINISTIC ECMWF HAS A SLIGHT EDGE OVER ITS GFS COUNTERPART. STARTING FROM A BLENDED MEDIUM RANGE MODEL INITIALIZATION...UTILIZED A VARIABLE WEIGHTING OF THE GFS/NAM/GEM/ECMWF...DEPENDING ON THE WEATHER ELEMENT IN QUESTION. THE EXTENDED FORECAST PERIOD STARTS (ON SATURDAY) WITH THE MEAN RIDGE AXIS DOMINATING THE AREA...SUPPRESSING ANY CONVECTION THROUGH AT LEAST EARLY SUNDAY. LOW PRESSURE CENTERS ROTATING NORTHEAST FROM THE NORTHWEST PACIFIC COAST INTERACT WITHE SEMIPERMANENT LOW WOBBLING ALONG ACROSS THE CANADIAN PROVINCES OF MANITOBA AND ONTARIO. AS THESE LOWS ARE PHASED INTO THE MEAN WEST- NORTHWEST BAROCLINIC ZONE BETWEEN THE CANADIAN LOW AND THE SOUTHER U.S. RIDGE SUNDAY NIGHT THROUGH TUESDAY...RAINFALL CHANCES ARE EXPECTED GENERATE A NORTH TO SOUTH GRADIENT OF POPS/WEATHER (HIGHEST NORTH NEAR INTERSTATE 64) DURING THIS TIME PERIOD. CONFIDENCE IS ABOUT 50/50 ON THE RANGE OF POPS/WEATHER...MAINLY DUE THE UNCERTAINTY ON ANY MESOSCALE PERTURBATIONS IN THE SAME FLOW...WHICH CAN ENHANCE/DIMINISH POPS FROM ONE PERIOD TO ANOTHER. THE RIDGE DOES NOT MOVE INTO THE AREA UNTIL WEDNESDAY...WHEN RELATIVELY DRY WEATHER RETURNS FOR THE END OF THE FORECAST PERIOD. MAXIMUM TEMPERATURES SHOULD REMAIN IN THE 80S DURING THE PERIOD...WITH LOWS IN THE UPPER 60S AND LOWER 70S...STILL BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION... ISSUED AT 1158 PM CDT WED AUG 5 2015 WITH THE APPROACH AND PASSAGE OF A FRONTAL BOUNDARY AND UPPER LEVEL TROUGH...VFR CONDITIONS WILL BECOME MVFR/IFR EARLY...ESPECIALLY IN SHRA/TSRA. MAY SEE VFR CONDITIONS AT KCGI/KPAH BY THE END OF THE PERIOD. SOUTH TO SOUTHWEST WINDS GENERALLY AOB 6 KNOTS WILL VEER AROUND TO THE NORTHWEST AND INCREASE TO AOB 10 KNOTS WITH THE FRONTAL PASSAGE. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR ILZ076>078-082- 083-086-087-089>094. FLASH FLOOD WATCH UNTIL 7 AM CDT THURSDAY FOR ILZ075-080-081-084- 085-088. MO...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR MOZ108>112-114. FLASH FLOOD WATCH UNTIL 7 AM CDT THURSDAY FOR MOZ076-086-087-100- 107. IN...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR INZ081-082- 085>088. KY...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR KYZ001>022. && $$ SHORT TERM...DRS LONG TERM...SMITH AVIATION...JP
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
216 AM EDT THU AUG 6 2015 .SYNOPSIS... A COLD FRONT LINGERS ACROSS NORTH CAROLINA OVERNIGHT AS HIGH PRESSURE MOVES EAST FROM THE GREAT LAKES. THE FRONT LIFTS BACK NORTH AS A WARM FRONT LATE TONIGHT THROUGH THURSDAY WITH LOW PRESSURE MOVING EAST ALONG IT THURSDAY NIGHT AND FRIDAY. HIGH PRESSURE SLOWLY RETURNS OVER THE WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... QUIET WX THIS EVE ACRS FA W/ WK SFC HI PRES INVOF THE RGN. WATCHING AREA OF CONVECTION SPREADING SLOLY ENE THROUGH SW VA/NW NC. CURRENT FCST APRS IN GOOD SHAPE ATTM...W/ POPS INCRS TO SLGT CHC-CHC ACRS MNLY HALF OF THE FA OVRNGT. ADDED ISOLD TSTMS UNTIL ABT 08-09Z. 23Z/05 RUC GENLY WEAKENS AREA OF CONVECTION AS IT SPREAD TWD/INTO THE FA. HOLDING ONTO SLGT CHC-CHC POPS LT. OTRW...PARTLY CLOUDY N...INCRSG CLDNS S...W/ LO TEMPS FM THE U60S/ARND 70F N TO THE M/U70S FAR SE. && .SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/... THE WARM FRONT LIFTS N INTO THE AKQ CWA THURSDAY. THE LOW-LEVEL THETA-E GRADIENT ACTUALLY SHARPENS AS HIGH PRESSURE REMAINS N OF THE REGION. MODELS HAVE COME INTO BETTER AGREEMENT AMONGST THE 12Z SOLUTIONS...ALTHOUGH SOME UNCERTAINTY REMAINS DUE TO THE CONVECTIVE NATURE OF THE ONSET OF THE EVENT. LIKELY POPS HAVE BEEN MAINTAINED ACROSS WRN/CENTRAL PORTIONS...AND LIKELIES HAVE BEEN ADDED TO NE NC/SE VA...AS MODELS SUGGEST AFTERNOON CONVECTION ACROSS THE COASTAL PLAIN OF ERN NC AND SE VA. OVERALL THE PRIMARY THREAT WILL BE LOCALLY HEAVY RAINFALL. HOWEVER...THERE DOES APPEAR TO BE A CORRIDOR FROM NE NC INTO SE VA WHERE A BELT OF STRONGER (30-35KT) 0-6KM BULK SHEAR INTERACTS WITH STRONGER INSTABILITY...WHICH COULD PRODUCE A LOCALIZED SEVERE THREAT. FORECAST HIGHS RANGE FROM THE UPPER 70S NE...TO AROUND 90 SE. LIKELY POPS ARE FORECAST FOR ALL AREAS THURSDAY NIGHT AS LOW PRESSURE DEEPENS ALONG THE SLOWLY ADVANCING WARM FRONT. THE COMBINATION OF A SLOW MOVING SYSTEM...AND ANOMALOUSLY HIGH PW VALUES WILL SUPPORT QPF AMOUNTS OF 1-2 INCHES WITH LOCALLY MUCH HIGHER AMOUNTS POSSIBLE FROM THURSDAY AFTERNOON THROUGH EARLY FRIDAY. HEAVY RAIN POTENTIAL WILL BE MAINTAINED IN THE HWO. LOWS SHOULD BE IN THE UPPER 60S TO LOWS 70S. MODELS BEGIN TO DIVERGE FRIDAY WITH RESPECT TO HOW FAST THE SYSTEM PULLS OFFSHORE. THE 12Z GFS SEEMS TO BE A REASONABLE COMPROMISE OF THE QUICKER NAM AND SLOWER ECMWF. LIKELY POPS WILL BE MAINTAINED GIVEN THE AMPLIFICATION OF THE OVERALL PATTERN...ALTHOUGH PCPN COULD TAPER OFF FROM THE W DURING THE AFTERNOON. CONTINUED LOW-LEVEL NE FLOW SHOULD RESULT IN PERSISTENT CLOUD COVER AND BELOW NORMAL HIGH TEMPERATURES. THIS WILL KEEP HIGHS BELOW NORMAL RANGING FROM THE MID 70S NW...TO THE LOW 80S SE. HIGH PRESSURE GRADUALLY BUILD IN FROM THE N FRIDAY NIGHT INTO SATURDAY. BY SATURDAY...THE SKY SHOULD BECOME PARTLY SUNNY W...AND REMAIN MOSTLY CLOUDY ALONG THE COAST WITH A 20-30% POP. LOWS RANGE FROM THE MID 60S TO LOW 70S FRIDAY NIGHT...WITH HIGHS IN THE LOW 80S SATURDAY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... STRENGTHENING SURFACE LOW PRESSURE MOVES OFF THE MID-ATLANTIC COAST SAT NIGHT...PULLING CLOUDS AND PRECIP OUT TO SEA WITH IT. WEAK HIGH PRESSURE MOVES OVER THE AREA SUN AND MON WITH INCREASING MID LEVEL DYNAMIC FORCING ON MONDAY. INCREASING POPS MONDAY THROUGH WED AS WEAK SURFACE TROUGH ON TUE AHEAD OF AN APPROACHING COLD FRONT HELPING TO INITIATE SCATTERED PRECIPITATION. FAIRLY GOOD MODEL AGREEMENT WITH THE TIMING OF THE UPPER WAVE AND SURFACE FRONT MOVING THROUGH THE AREA ON WEDNESDAY WITH WIDESPREAD PRECIP POSSIBLE. MODELS DEPICT AN OMEGA LIKE BLOCK FOR THE END OF THE EXTENDED FORECAST...KEEPING UPPER LEVEL LOW OVER THE AREA WHICH WILL HELP MAINTAIN CLOUDS AND ISOLATED SHOWERS IN THE FORECAST. TEMPS UPPER 80S MON AND TUES AHEAD OF THE FRONT WED MODERATING INTO THE LOW TO MID 80S ON THURS. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... LATEST REGIONAL RADAR MOSAIC DEPICTS AN AREA OF SHOWERS/THUNDERSTORMS LIFTING ALONG A QUASI STATIONARY BOUNDARY EARLY THIS MORNING. THESE SHOWERS/THUNDERSTORMS WILL CONTINUE TO LIFT NEWD INTO CENTRAL VA...IMPACTING KRIC DURING THE FIRST FEW HOURS OF THE 06Z TAF ISSUANCE. BRIEF HEAVY RAINFALL...GUSTY WINDS AND OCCASIONAL LIGHTNING IS EXPECTED WITH THESE STORMS. ISOLATED SHOWERS/THUNDERSTORMS ALSO DEVELOPING OVER THE MD ERN SHORE. WILL MAINTAIN DRY FORECAST FOR KSBY...BUT WILL NEED TO MONITOR. ELSEWHERE...VFR CONDITIONS PREVAIL THIS MORNING WITH BKN HIGH CLOUDS AOA 20K FT AGL AND WINDS AOB 10 KT. WARM DEWPOINTS AND ONLY HIGH CLOUDS OVER NE NC WILL LIKELY PRODUCE SOME PATCHY GROUND FOG THIS MORNING. HAVE INCLUDED IFR VISIBILITIES FOR KECG EARLY THIS MORNING. FOR TODAY...LOW PRESSURE PROGGED TO DEVELOP ALONG THE FRONT OVER ERN NC AS ANOTHER AREA OF LOW PRESSURE APPROACHES FROM THE WEST. MID-HIGH CLOUDS THIS MORNING WILL LOWER TO BKN-OVC SKIES WITH DECKS 4-6K FT AGL THIS AFTERNOON. A BRIEF BREAK IN THE PRECIP EXPECTED THIS MORNING...BEFORE SHOWERS/THUNDERSTORMS SPREAD IN FROM THE WEST THIS AFTERNOON. WIDESPREAD SHOWERS/THUNDERSTORMS ARE FORECAST WITH MODERATE TO LOCALLY HEAVY RAINFALL EXPECTED TO PERSIST INTO THE EVENING...BEYOND THE 06Z TAF ISSUANCE. IFR CONDITIONS ARE POSSIBLE IN THE STRONGEST STORMS/HEAVIEST SHOWERS. SCATTERED TO NUMEROUS SHOWERS/THUNDERSTORMS PERSIST TONIGHT AS LOW PRESSURE REORGANIZES OVER THE CAROLINAS. UNSETTLED CONDITIONS CONTINUE INTO THE WEEKEND AS THE LOW SLOWLY PUSHES OFF THE NC COAST. HIGH PRESSURE BUILDS IN FROM THE WEST THRU THE WEEKEND. && .MARINE... AN AREA OF LOW PRESSURE PROGGED TO DEVELOP ALONG A STALLED FRONTAL BOUNDARY THURSDAY AS HIGH PRESSURE BUILDS INTO NEW ENGLAND. THE RESULT WILL BE ONSHORE FLOW THURS AOB 15 KT. GRADIENT STRENGTHENS THURS NIGHT AS THE LOW DEEPENS IN THE VICINITY OF EASTERN NC. MODELS COMING INTO BETTER AGREEMENT WITH RESPECT TO THE LOW PLACEMENT AND RESULTANT FRONTAL LOCATION. CONFIDENCE CONTINUES TO INCREASE FOR STRONG SCA CONDITIONS FRIDAY INTO SATURDAY DUE TO STRENGTH OF THE PRESSURE GRADIENT AND NE FLOW. SEAS RESPOND...BUILDING TO 4 T0 6+ FT FRI NIGHT THOUGH SAT. LOW PROGGED TO LIFT AWAY FROM THE COAST SAT NIGHT INTO SUN...ALLOWING THE GRADIENT TO RELAX AND WINDS/SEAS TO SLOWLY DIMINISH/SUBSIDE. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...AJZ/ALB/LKB NEAR TERM...AJZ/ALB SHORT TERM...AJZ/LKB LONG TERM...DAP AVIATION...SAM MARINE...MAS/DAP
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
438 AM EDT THU AUG 6 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 435 AM EDT THU AUG 6 2015 UPPER GREAT LAKES IS WITHIN WESTERLY FLOW ALOFT BETWEEN LARGE UPPER LOW OVER EASTERN CANADA AND UPPER TROUGH OVER FAR WESTERN CANADA. COUPLE OF MAIN SHORTWAVES ARE UPSTREAM OF UPPER GREAT LAKES. THE LEAD WAVE IS OVER SOUTHERN MANITOBA AND IS GENERATING CLUSTER OF SHRA/TSRA SOUTHERN MANITOBA INTO NORTHWEST MINNESOTA. WARM AIR ADVECTION MAINLY IN THE MID LEVELS IS SUPPORTING ARC OF LGT SHRA TOWARD ISLE ROYALE AND NORTHERN LK SUPERIOR. BASED ON HRRR AND RAP AND CURRENT RADAR TRENDS...COULD SEE ISOLD SHR OR SPRINKLES CLIP TIP OF KEWEENAW PENINSULA THIS MORNING. OTHERWISE...MAIN EFFECT FM THIS SHORTWAVE WILL BE A LOT OF MID CLOUDS OVER AT LEAST NORTHERN CWA MOST OF TODAY. SINCE THERE ARE ALREADY A WIDESPREAD AREA OF 5-10KFT BKN CIGS UPSTREAM IN MINNESOTA...BUMPED UP CLOUD COVER TODAY. SOUTHERN CWA SHOULD STAY IN AT LEAST INTERVALS OF SUN AND CLOUDS SO WENT WARMEST THERE WITH MID 70S NEAR WI BORDER. COOLEST READINGS IN THE UPR 60S TO NEAR 70 DEGREES WILL BE CLOSER TO LK SUPERIOR WITH MORE CLOUD COVER AND EAST-SOUTHEAST ONSHORE GRADIENT WINDS. FOR TONIGHT...ATTN TURNS TO SHORTWAVE CURRENTLY OVER WY AND SD. THIS SHORTWAVE MOVES ACROSS NORTHERN PLAINS AND ARRIVES OVER CNTRL MN AND WESTERN WI BY LATE TONIGHT. BULK OF STRONGER Q-VECTOR CONVERGENCE STAYS OUT AHEAD OF THAT SHORTWAVE...BUT AS ASSOCIATED SFC LOW WITH THE WAVE MOVES OVER MN...STRONG MOISTURE ADVECTION AT H85 ALONG WITH ISENTROPIC LIFT 300-305K /H9-H7/ SHOULD SUPPORT INCREASING SHOWERS INTO WESTERN UPR MICHIGAN AFTER MIDNIGHT. POPS RAMP UP TO HIGHER CHANCE AT KIWD AFTER MIDNIGHT WITH SLIGHT CHANCES AS FAR EAST AS ISHPEMING AND IRON MOUNTAIN. MUCAPE IN LOWEST 3KM OR APPROX SFC-H7 STAYS MAINLY SOUTHWEST OF CWA. ISOLD TSRA COULD SNEAK INTO FAR WEST AS MODEST LOW-LEVEL JET MAY COULD ADVECT SMALL PORTION OF INSTABILITY INTO CWA...BUT WILL KEEP TSRA OUT OF CWA THROUGH 12Z FRIDAY. MIN TEMPS MUCH WARMER THAN LAST COUPLE NIGHTS MID 50S TO LOW 60S DUE TO PLENTY OF CLOUD COVER AND STEADY SOUTH WINDS AHEAD OF THE SFC LOW IN MN. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 347 AM EDT THU AUG 6 2015 NAM SHOWS A SHORTWAVE OVER THE NORTHERN PLAINS 12Z FRI WITH ANOTHER ENTERING INTO THE UPPER GREAT LAKES THEN. THIS SHORTWAVE MOVES THROUGH ON FRI AND THE OTHER SHORTWAVE MOVES SLOWLY EAST AND AFFECTS THE AREA ON SAT. NAM SHOWS SOME 850-500 MB Q-VECTOR CONVERGENCE AND MOISTURE MOVING THROUGH ON FRI AND BOTH MOVE OUT SAT AFTERNOON BEFORE RETURNING SAT NIGHT. CONFIDENCE IS LOW WITH THIS FORECAST AS GFS...ECMWF AND NAM ALL HAVE DIFFERENT IDEAS FOR HOW THIS WEATHER SCENARIO IS GOING TO PLAY OUT. ECMWF IS DRIER AND FURTHER SOUTH WITH IT PCPN. GFS IS QUICKER MOVING PCPN THROUGH. WENT WITH A BLEND OF THE SOLUTIONS WHICH SEEMED TO KEEP SOME CONTINUITY TO THE FORECAST. LOOKS LIKE THERE WILL BE A BREAK IN PCPN FOR LATE FRI NIGHT INTO SAT MORNING AND THEN ANOTHER WAVE COMES IN AND TRIED TO REFLECT THIS IN THE FORECAST WITH A BREAK IN THE PCPN. BEST CHANCE FOR PCPN APPEARS TO BE FRI INTO FRI EVENING...THEN HAVE LOW CHANCE POPS AND LOW CONFIDENCE FOR SAT AND SAT NIGHT. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE OVER THE SOUTHERN AND CENTRAL PLAINS 12Z SUN WITH A TROUGH ACROSS CENTRAL CANADA AND A SHORTWAVE IN THE NORTHERN PLAINS. THIS SHORTWAVE HEADS EAST INTO THE UPPER GREAT LAKES SUN NIGHT INTO MON. THIS SHORTWAVE HEADS OVER THE TOP OF THE RIDGE ON MON AND PUSHES IT BACK INTO THE NORTHERN ROCKIES. THE UPPER FLOW BECOMES MORE AMPLIFIED ON TUE WITH THE RIDGE BUILDING INTO THE CANADIAN ROCKIES AND THE TROUGH DIGGING INTO THE ERN U.S. THE RIDGE BUILDS INTO THE NORTHERN PLAINS 12Z WED. SFC RIDGING MOVES INTO THE UPPER GREAT LAKES TUE AND REMAINS INTO WED. TEMPERATURES WILL CONTINUE TO BE SLIGHTLY BELOW NORMAL FOR THIS FORECAST PERIOD. AS THE SFC HIGH BUILDS IN FOR MONDAY...WENT DRY FOR MON NIGHT THROUGH WED AND REMOVED POPS FOR THAT TIME PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 138 AM EDT THU AUG 6 2015 VFR CEILING AND VIS ARE EXPECTED THROUGH THE PERIOD WITH DIURNAL WINDS AND AFTERNOON LAKE BREEZES OFF LAKE SUPERIOR. THERE IS A SMALL POTENTIAL FOR EARLY MORNING FOG OVER THE INTERIOR W HALF OF UPPER MI BUT NOT EXPECTING IT TO IMPACT TAF SITES. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 435 AM EDT THU AUG 6 2015 A COUPLE OF WEAK TROUGHS OR LOW PRESSURE SYSTEMS WILL MOVE THROUGH THE UPPER GREAT LAKES REGION THROUGH THIS WEEKEND...BUT WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...07 AVIATION...VOSS MARINE...SRF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1250 AM CDT THU AUG 6 2015 .UPDATE... ISSUED AT 1244 AM CDT THU AUG 6 2015 UPDATED 06Z AVIATION DISCUSSION BELOW... UPDATE ISSUED AT 847 PM CDT WED AUG 5 2015 LATEST HRRR RUNS INDICATE A SLOWER ONSET OF SHOWERS AND STORMS TO THE WESTERN EDGE OF THE FORECAST AREA UNTIL 12Z. DRY AIR FROM HIGH PRESSURE OVER LAKE SUPERIOR WILL WIN OUT OVER THE RAIN AND ADJUSTED ACCORDINGLY. UPDATE ISSUED AT 657 PM CDT WED AUG 5 2015 LATEST SHORT TERM HIRES MODELS INCLUDING THE NMM/ARW DELAY THE ONSET OF SHOWERS AND STORMS TO AFTER 09Z. HAVE MADE SOME ADJUSTMENTS TO ACCOUNT FOR THAT TREND. REFLECTIVITY SHOWING UP ON KDLH 88D ATTM ARE CLOUDS WITH A MINIMUM 12K FT BASE. REST OF THE FORECAST ON TRACK. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 313 PM CDT WED AUG 5 2015 A WARM AIR ADVECTION REGIME RETURNS TO THE FORECAST AREA OVERNIGHT AS WARM FRONT LIFTS NORTH INTO CANADA...AND A VORT MAX/H85 LOW TRANSLATES EAST ACROSS NORTH DAKOTA/SOUTHERN MANITOBA...REACHING THE NW CORNER OF MN BY DAYBREAK THURSDAY. THE VORT MAX THEN DIMINISHES/STALLS OVER NW MINNESOTA MONDAY MORNING WHILE BECOMING ABSORBED BY ANOTHER FAST APPROACHING WAVE IN THE DAKOTAS. THIS RAPIDLY DEEPENING WAVE...IN A REGION OF STRONG UPPER LVL DIVERGENCE...BECOMES A CLOSED LOW AND PUSHES INTO WESTERN MINNESOTA BY THURSDAY EVENING. THE NORTHLAND WILL BE POSITIONED IN A SOUTHERLY FLOW WITH INCREASING MOISTURE AND INSTABILITY AHEAD OF THE LOW THROUGH THE DAY THURSDAY. PWATS INCREASE TO NEAR 2 INCHES THURSDAY WHILE DEW POINTS SURGE INTO THE 60S OVER NORTH CENTRAL MN. A FEW STORMS COULD BE STRONG TO LOW-END SEVERE THURSDAY...MAINLY OVER NORTH-CENTRAL MN WHERE THE LATEST NAM IS SHOWING AROUND 2000 J/KG OF CAPE DEVELOPING IN THE AFTERNOON. HOWEVER..THE MAIN THREAT WITH ANY STORMS THURSDAY LOOKS TO BE PERIOD OF VERY HEAVY RAINFALL AND LOCALIZED FLOODING. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 313 PM CDT WED AUG 5 2015 THE MAIN CONCERN IN THE LONG TERM WILL BE AN APPROACHING LOW PRESSURE SYSTEM THURSDAY NIGHT WITH ASSOCIATED FRONTAL BOUNDARY. MODELS ARE IN AGREEMENT AS FAR AS THE OVERALL PATTERN IS CONCERN FRIDAY AND SATURDAY... INCREASING DEWPOINTS TO THE 60S... SOLID WARM AIR ADVECTION AND A GENERAL LIKELIHOOD OF SHOWERS AND STORMS. HOWEVER MODELS DIVERGE ON THE EVENTUAL PATH OF THE LOW AND WHERE THE BULLS- EYE OF THE QPF WILL BE. 12Z NAM12 HAS THE LOW TAKING A NOSE DIVE TO SOUTHERN MINNESOTA AND IOWA WITH A LINE OF PRECIP BREAKING APART ACROSS THE NORTHLAND... THE GFS40 STALLING BUT ALSO MARCHING THROUGH SOUTHERN MINNESOTA... AND THE ECMWF STICKING TO A MORE NORTHERN SOLUTION ACROSS CENTRAL PARTS OF THE STATE AND NORTHERN WISCONSIN. OVERALL DELAYED THE ONSET OF INITIAL FRIDAY PRECIP ALONG THE WARM FRONT IN COLLABORATION WITH NEIGHBORING OFFICES. EXPECT ANOTHER CHANCE OF SHOWERS AND STORMS TO MOVE THROUGH SATURDAY WITH THE SECOND BOUNDARY... BUT QPF WILL LIKELY BE HIGHEST ON FRIDAY. DEWPOINTS WILL DROP BACK INTO THE MORE COMFORTABLE 50S FOR MOST OF THE CWA BY MONDAY AS A HIGH PRESSURE RIDGE BUILDS BACK IN ACROSS THE UPPER MIDWEST... THOUGH EXPECT THE SUMMER WARMTH TO REMAIN... WITH MID TO UPPER 70 HIGHS IN THE FORECAST NEXT WORK WEEK. AFTER A SHORTWAVE BRINGS A SHOT OF SHOWERS ACROSS OUR SOUTH MONDAY... THE REST OF THE WEEK LOOKS MOSTLY DRY AND PARTLY CLOUDY TO SUNNY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1244 AM CDT THU AUG 6 2015 MAINLY VFR CIGS/VSBYS FOR THIS TAF PERIOD...EXCEPT FOR A FEW HOURS BEFORE SUNRISE WHERE MVFR VSBYS ARE EXPECTED AT HYR/BRD IF SKIES REMAIN CLEAR. APPROACHING LOW PRESSURE FROM THE PLAINS WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS LATER TODAY/EARLY TONIGHT. A FEW STRAY SHOWERS MAY ARRIVE AT BRD EARLIER THAN OTHER SITES. OPTED FOR VCSH/VCTS FOR PRECIPITATION CHANCES AS CONFIDENCE IN TIMING PREVAILING CONDITIONS WAS TOO LOW THIS MORNING. WHEN THUNDERSTORMS MOVE OVER TERMINALS...EXPECT TEMPORARY VSBYS REDUCTIONS INTO MVFR/IFR CATEGORIES FOR A PERIOD. AGAIN...TIMING CONCERNS DIDN`T WARRANT INCLUSION AS TEMPO GROUPS FOR LOWER VIS...WILL LET LATER UPDATES HANDLE TIMING. THUNDERSTORM POTENTIAL SHOULD DIMINISH QUICKLY TOMORROW EVENING WITH RAIN SHOWERS LINGERING THROUGH REMAINDER OF TAF PERIOD. && .PRELIMINARY POINT TEMPS/POPS... DLH 61 71 60 78 / 60 50 30 20 INL 59 72 56 78 / 50 40 30 40 BRD 62 77 59 80 / 80 50 10 30 HYR 62 73 57 80 / 60 60 30 20 ASX 60 74 57 78 / 40 60 30 20 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...NONE. && $$ UPDATE...GSF SHORT TERM...GRANING LONG TERM...MCLOVIN AVIATION...HUYCK
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1130 PM CDT WED AUG 5 2015 .SHORT TERM...(TONIGHT THROUGH THURSDAY) ISSUED AT 406 PM CDT WED AUG 5 2015 MAP ANALYSIS INDICATES UPPER TROPOSPHERIC RIDGING OVER THE WESTERN TWO-THIRDS OF THE CONUS...AND A TROUGH OVER THE EAST. AN UPPER TROPOSPHERIC SHORT WAVE IS ALSO NOTED MOVING ACROSS PORTIONS OF THE CENTRAL PLAINS AND MISSOURI RIVER VALLEY. AT THE SURFACE A WEAK RIDGE OF HIGH BAROMETRIC PRESSURE IS NOTED ACROSS PORTIONS OF THE CENTRAL PLAINS AND MISSOURI RIVER VALLEY AND AS A RESULT...THE BOUNDARY-LAYER WIND FIELD ACROSS THE AREA REMAINS FAIRLY WEAK AND AT TIMES VARIABLE. GUIDANCE SUGGESTS THE UPPER TROPOSPHERIC SHORT WAVE...CURRENTLY CLEARING THE AREA...WILL CONTINUE MOVING EAST/SOUTHEAST THROUGH THE NEXT 24 HOURS...LIKELY CLEARING THE MISSOURI RIVER VALLEY LATER TONIGHT. QUASI-ZONAL UPPER TROPOSPHERIC FLOW IS THEN EXPECTED TO OVERTAKE THE AREA THROUGH THURSDAY...ALTHOUGH THERE ARE INDICATIONS OF ANOTHER UPPER TROPOSPHERIC SHORT WAVE CLEARING THE AREA THURSDAY INTO THURSDAY EVENING. AN OVERALL LACK IN OMEGA WOULD OTHERWISE KEEP THE AREA DRY THROUGH TONIGHT...BUT SOMEWHAT ENHANCED UPPER TROPOSPHERIC LAPSE RATES IN ASSOCIATION WITH THE PASSING SHORT WAVE TROUGH AXIS COULD BE ENOUGH TO PROMOTE WEAK SHOWER AND/OR THUNDERSTORM DEVELOPMENT ACROSS THE SOUTH/SOUTHEASTERN TWO-THIRDS OF THE CWA. THIS IS A SOLUTION SUPPORTED BY QPF FIELDS FROM THE NAM AND OPERATIONAL GFS...AND TO A LESSER EXTEND THE EC. THIS IS ALSO SUPPORTED BY SIMULATED REFLECTIVITY FROM THE HRRR AND 4KM WRF-NMM. GIVEN ALL THIS...OPTED TO GO AHEAD WITH ~20% POPS ACROSS THE SOUTH/SOUTHEASTERN TWO-THIRDS OF THE CWA UNTIL 00Z. DRY CONDITIONS ARE THEN FORECAST THROUGH THE OVERNIGHT HOURS AS DIABATIC HEATING IS LOST. GUIDANCE THEN SUGGESTS YET ANOTHER CHANCE FOR PRECIPITATION COULD BE REALIZED THURSDAY INTO THURSDAY EVENING AS THE SECOND UPPER TROPOSPHERIC SHORT WAVE CLEARS THE AREA. GIVEN THIS...WENT AHEAD WITH 20-40% POPS ACROSS MUCH OF THE CWA THURSDAY INTO THURSDAY EVENING. DESPITE FAIRLY RICH BOUNDARY-LAYER MOISTURE ACROSS THE REGION...LAPSE RATES REALLY SHOULD NOT BE ANYTHING TO WRITE HOME ABOUT AND IN FACT...GUIDANCE SUGGESTS NO MORE THAN ~500J/KG OF POTENTIAL ENERGY WILL BE AVAILABLE FOR UPDRAFT PRODUCTION THROUGH THIS EVENING. GIVEN THIS...WILL NOT INTRODUCE STRONG/SEVERE THUNDERSTORM WORDING IN THE HWO. LAPSE RATES ARE SOMEWHAT MORE RESPECTABLE THURSDAY AFTERNOON AND EVENING AND GUIDANCE RESPONDS BY PROVIDING POTENTIAL ENERGY VALUES MORE IN THE 1000-2000J/KG RANGE. IN ADDITION...DEEP-LAYER BULK SHEAR OF ~40KTS IS ALSO EXPECTED THURSDAY AFTERNOON AND EVENING AND GIVEN ALL THIS...FELT IT PRUDENT TO AT LEAST GO WITH STRONG THUNDERSTORM WORDING IN THE HWO. FINALLY...A CONTINUED WEAK BOUNDARY-LAYER WIND FIELD THROUGH THE OVERNIGHT HOURS...WORKING IN CONCERT WITH A NEAR-ZERO DEW POINT DEPRESSIONS...COULD PROMOTE AT LEAST PATCHY FOG DEVELOPMENT ACROSS MUCH OF THE AREA TONIGHT. GIVEN THIS...WENT AHEAD WITH PATCHY FOG IN THE GRIDS 06-14Z THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 406 PM CDT WED AUG 5 2015 GUIDANCE SUGGESTS QUASI-ZONAL UPPER TROPOSPHERIC FLOW WILL BE NOTED ACROSS THE REGION THROUGH MUCH OF THE LONG-TERM FORECAST PERIOD...WITH THE ONLY EXCEPTION BEING EARLY NEXT WEEK AS AN UPPER TROPOSPHERIC SHORT WAVE CLEARS THE AREA AND RIDGING STRENGTHENS OVER THE WESTERN CONUS. MULTIPLE UPPER TROPOSPHERIC PERTURBATIONS ARE ALSO EXPECTED TO CLEAR THE AREA AND AS A RESULT...POPS...GENERALLY IN THE 20-40% RANGE...REMAIN INTACT ACROSS VARIOUS PORTIONS OF THE CWA THROUGH EARLY NEXT WEEK. STRONG AND/OR SEVERE CONVECTION CERTAINLY CANNOT BE RULED OUT LATE THIS WEEK INTO EARLY NEXT WEEK...BUT AT THIS TIME IT REMAINS TOO EARLY TO TRY AND PIN DOWN TIMING OR PLACEMENT OF SUCH ACTIVITY. LITTLE CHANGE IN THE BOUNDARY-LAYER AIR MASS SHOULD PROVIDE SIMILAR TEMPERATURE READINGS FROM DAY TO DAY DURING THE LONG-TERM FORECAST PERIOD...WITH HIGHS GENERALLY IN THE 80S AND LOWS IN THE 60S. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1130 PM CDT WED AUG 5 2015 VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE PERIOD. MVFR VSBY POSSIBLE FOR A SHORT TIME PRIOR TO AND AFTER SUNRISE...OTHERWISE HIGH LEVEL CLOUDS WILL PREDOMINATE. SOUTH WINDS INCREASING AFTER 17Z AT KOFK WITH GUSTS TO 25 KTS IN ADVANCE OF APPROACHING SURFACE TROUGH. WINDS DIMINISH TO LESS THAN 10 KTS AFTER 00Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...BRYANT LONG TERM...BRYANT AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1255 AM CDT THU AUG 6 2015 .UPDATE... ISSUED AT 1255 AM CDT THU AUG 6 2015 A SMALL AREA OF THUNDERSTORMS ALONG THE ND/SD BORDER CONTINUED IN THE MCINTOSH/DICKEY COUNTY AREA...LIKELY ASSOCIATED WITH LIFT FROM THE ESTABLISHED LOW LEVEL JET IN PLACE OVER THE EASTERN DAKOTAS. MEANWHILE THE WESTERN SHORTWAVE AND ASSOCIATED UPPER LEVEL ENERGY IMPULSES WILL CONTINUE MOVING EAST/NORTHEAST FROM MONTANA/WYOMING AND MOVING INTO THE DAKOTAS THIS MORNING. ADJUSTED PRECIP CHANCES ACCORDING TO CURRENT RADAR OBSERVATIONS AND LATEST ITERATIONS OF THE HRRR MODEL RUN. OTHERWISE OTHER FORECAST ELEMENTS ON TRACK. UPDATE ISSUED AT 921 PM CDT WED AUG 5 2015 VERY ISOLATED THUNDERSTORMS CONTINUE EAST OF THE MISSOURI RIVER. AN AREA OF THUNDERSTORMS WILL BE MOVING INTO THE SOUTHWEST AFTER 10 PM CDT. UPDATED POPS FOR CURRENT TRENDS. WATER VAPOR IMAGERY SHOWS SHORTWAVE TROUGH MOVING THROUGH NORTH CENTRAL WYOMING. THIS WILL LIFT INTO SOUTHWEST NORTH DAKOTA OVERNIGHT. CURRENT FORECAST TRENDING OK. UPDATE ISSUED AT 638 PM CDT WED AUG 5 2015 WARM FRONT ACROSS CENTRAL NORTH DAKOTA WILL BE THE FOCUS FOR SCATTERED TO ISOLATED THUNDERSTORMS ACROSS CENTRAL AND EASTERN NORTH DAKOTA THIS EVENING. A COLD FRONT ACROSS SOUTHEAST SASKATCHEWAN WILL MOVE SOUTHEAST AND BE THE FOCUS FOR NUMEROUS THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA AFTER MIDNIGHT. HRRR MODEL CONTINUES TO SPREAD THUNDERSTORMS SOUTHWEST TO NORTHEAST ACROSS THE STATE LATE TONIGHT WITH A MID LEVEL SHORTWAVE TROUGH CURRENTLY OVER EASTERN IDAHO. THIS STILL LOOKS REASONABLE. MAIN UPDATES TO FORECAST WERE CURRENT CONDITIONS AND TIMING OF POPS WEST. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 302 PM CDT WED AUG 5 2015 HIGHLIGHTS OF THE SHORT TERM IS CONVECTIVE POTENTIAL THIS AFTERNOON AND HEAVY RAINFALL ON THURSDAY. FOR THE REMAINDER OF THE AFTERNOON...EXPECTING ISOLATED TO SCATTERED SURFACE BASED CONVECTIVE DEVELOPMENT EAST OF THE WARM FRONT NEAR US HIGHWAY 85. 18 UTC RAP ANALYSIS DEPICTS 1500-2000 J/KG OF ML CAPE AND DEEP LAYER SHEAR OF 30-40 KTS AHEAD OF THE BOUNDARY. THUS...A FEW STRONG TO POSSIBLY SEVERE STORMS ARE POSSIBLE...IN LINE WITH THE 18-19 UTC HRRR ITERATIONS AND SPC DAY 1 OUTLOOK. A STRONG SHORTWAVE IS FORECAST TO PROPAGATE OUT OF THE INTERMOUNTAIN WEST AND ONTO THE NORTHERN PLAINS LATE THIS EVENING AND TONIGHT...AND STRENGTHEN THROUGH THE DAY ON THURSDAY. EXPECTING WIDESPREAD THUNDERSTORMS SOUTH OF US HIGHWAY 2 ENTERING THE SOUTHWEST TONIGHT...AND FOCUSING CENTRAL THROUGH THURSDAY AFTERNOON. PWATS OF 1.50 TO 1.75 INCHES WITH TALL...SKINNY CAPE PROFILES...AND WEAK WINDS THROUGHOUT THE TROPOSPHERE SUPPORTING SLOW STORM MOTIONS ALL POINT TO A HEAVY RAINFALL THREAT. AREAS THAT WILL RESIDE IN THIS ENVIRONMENT THE LONGEST IS THE SOUTH CENTRAL AND JAMES RIVER VALLEY LATE THURSDAY MORNING THROUGH THE EVENING. THIS IS SUPPORTED BY 00 UTC GEFS QPF MODEL CLIMATE IN THE MAXIMUM PERCENTILES FOR THESE AREAS THURSDAY AFTERNOON...WHICH HAS BEEN NOTED AS A FLASH FLOOD SIGNAL IN PREVIOUS EVENTS ACROSS THE CONUS. THUS...HAVE ISSUED A FLASH FLOOD WATCH FOR THE SOUTH CENTRAL AND JAMES RIVER VALLEY FOR THURSDAY. ALTHOUGH SOME OF THESE AREAS HAVE BEEN RELATIVELY DRY OVER THE RECENT WEEKS...POTENTIAL EXCESSIVE RAINFALL RATES MAY STILL LEAD TO FLASH FLOODING EVEN WITH DRY SOILS. FLASH FLOODING OF URBAN AREAS...INCLUDING MANDAN...BISMARCK AND JAMESTOWN ARE ALSO POSSIBLE WITH THESE SLOW MOVING...HEAVY RAINFALL PRODUCING STORMS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 302 PM CDT WED AUG 5 2015 SHORTWAVE TROUGH WILL BE EXITING THE JAMES RIVER VALLEY THURSDAY NIGHT/06-12 FRIDAY AS LIKELY POPS DWINDLE AND THE PRECIPITATION COMES TO AN END. UPPER LOW WILL MOVE ACROSS SOUTHERN CANADA FRIDAY THROUGH SATURDAY DRAGGING TWO SURFACE COLD FRONTS THROUGH...ONE FRIDAY NIGHT AND A SECONDARY COLD FRONT SATURDAY. FRIDAY LOOKS DRY WITH THE INITIAL FRONT. HOWEVER FRIDAY NIGHT AND SATURDAY...ASSOCIATED WITH THE SECOND FRONT WILL BE THE RIGHT ENTRANCE REGION OF A 70KT-80KT JET STREAK SLIDING THROUGH CENTRAL NORTH DAKOTA ATOP OF A SURFACE LOW PRESSURE SCOOTING ACROSS NORTHERN SOUTH DAKOTA. AN AREA OF PRECIPITATION DEVELOPS OVER OR NEAR SOUTHERN NORTH DAKOTA SATURDAY IN RESPONSE TO THE LOW LEVEL CONVERGENCE AND THE UPPER LEVEL DIVERGENCE AREA ASSOCIATED WITH THE JET. ALTHOUGH WEAK NORTHWEST FLOW ENSUES SATURDAY NIGHT INTO SUNDAY...THERE IS SOME QUESTION AS TO WHETHER OR NOT THE FRONT STALLS ALONG/NEAR OR SOUTH OF THE SOUTHERN BORDER SUNDAY FOR CONTINUED PRECIPITATION CHANCES. AS OF NOW IT APPEARS THAT CHANCES FOR PRECIPITATION BEGIN ALONG INTERSTATE 94 AND INCREASE SOUTH TOWARDS THE BORDER SUNDAY. THEREAFTER A CENTRAL CONUS UPPER LEVEL RIDGE DEVELOPS WITH A TROUGH SETTLING INTO THE WEST FOR DRY AND WARM CONDITIONS MONDAY AND TUESDAY. THERE MAY BE POTENTIAL SHORTWAVES TRYING TO BREAK DOWN THE RIDGE BY MID WEEK OR SIGNS OF THE RIDGE SHIFTING EAST A BIT FOR POSSIBLE SHOWERS AND THUNDERSTORMS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1255 AM CDT THU AUG 6 2015 MAIN HAZARDS TO AVIATION WILL BE THUNDERSTORMS AND POSSIBLE MVFR TO IFR CONDITIONS IN THE THUNDERSTORM VCNTY. AT MIDNIGHT CDT...A WARM FRONT EXTENDED ACROSS CENTRAL NORTH DAKOTA IN THE VICINITY OF HIGHWAY 83. A COLD FRONT EXTENDED ACROSS THE BORDER OF MONTANA AND SOUTHERN SASKATCHEWAN. THE COLD FRONT WILL MOVE SOUTHEAST AND...WITH VIGOROUS UPPER LEVEL SHORTWAVE ENERGY...WILL BECOME THE FOCUS FOR NUMEROUS THUNDERSTORMS ACROSS WEST AND CENTRAL NORTH DAKOTA THIS MORNING AND THROUGH MUCH OF THE DAY ON THURSDAY. CONDITIONS MAY BECOME MVFR TO IFR IN THE AREAS OF THUNDERSTORMS KMOT AFT 01Z. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH FROM 10 AM CDT /9 AM MDT/ THIS MORNING THROUGH THIS EVENING FOR NDZ019>023-025-034>037-042-045>048-050-051. && $$ UPDATE...JV SHORT TERM...AYD LONG TERM...KS AVIATION...JV
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
526 AM EDT THU AUG 6 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK TO THE SOUTH OF PENNSYLVANIA THROUGH THE END OF THE WEEK AND MOVE OFFSHORE THIS WEEKEND. HIGH PRESSURE WILL MOVE INTO THE AREA BEHIND THE DEPARTING LOW. RAIN IS LIKELY NEAR THE MASON DIXON LINE THIS AFTERNOON INTO TONIGHT BEFORE CONDITIONS DRY OUT FOR THE MOST PART ON FRIDAY. && .NEAR TERM /UNTIL NOON TODAY/... PATCHY FOG ACROSS THE NORTHERN TIER WILL DISSIPATE AROUND 12Z. HIGH-TO-MID CLOUDS WILL INCREASE FROM SW TO NE THROUGH MID DAY IN ADVANCE OF WELL DEFINED MID/UPPER LEVEL SYSTEM /FOR THIS TIME OF YEAR/ AND DEVELOPING SFC LOW OVER THE MID MS/LOWER OH VALLEY. SFC HIGH EXTENDING SEWD FROM THE UPPER GREAT LAKES AND LOW PW AIR WILL KEEP DRY WX INTACT THIS MORNING. && .SHORT TERM /NOON TODAY THROUGH 6 AM FRIDAY/... SHORT TERM MODELS ARE IN GOOD AGREEMENT IN TAKING THE H5 HEIGHT FALL CENTER AND SFC REFLECTION TO THE SOUTH OF CENTRAL PA THROUGH THE PERIOD...FROM KY EWD ACROSS THE CENTRAL APPALACHIANS AND INTO THE SRN MID ATLC. HOWEVER...THERE CONTINUES TO BE SOME UNCERTAINTY WITH RESPECT TO THE QPF DISTRIBUTIONS/WARM SEASON OVERRUNNING SCENARIO TO THE NORTH OF THE SFC WAVE. FOR THIS REASON STAYED PRETTY CLOSE TO A BLENDED SOLUTION WITH WPC QPF...WHICH LEANED TOWARD THE HI RES MODELS. THE FINAL NDFD FCST WILL SHOW AN INCREASE IN POPS OVER THE FAR SRN TIER ZONES FROM THE PA TURNPIKE SWD TO THE MASON DIXON LINE. THE LATEST HRRR AND 00Z SSEO ARE STRADDLING THE PA/MD LINE WITH SHOWER ACTIVITY THRU 18-21Z TIME FRAME. THERE SHOULD BE A FAIRLY SHARP GRADIENT TO THE NRN EDGE OF THE RAIN AND MODELS MAY BE TOO BULLISH ON WAA/OVERRUNNING COMPONENT IN LIEU OF CONVECTION FARTHER TO THE SOUTH. LATER SHIFTS MAY NEED TO MAKE N-S ADJUSTMENTS IN P0PS/QPF AS THE PCPN PATTERN EVOLVES THROUGH EARLY TONIGHT. POPS WILL TREND LOWER FROM NW TO SE INTO EARLY FRIDAY WITH M/CLR SKIES/PATCHY FOG OVER THE NW MTNS BY FRIDAY MORNING. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... A FEW LINGERING SHRA MAY AFFECT THE SE COUNTIES INTO PART OF FRIDAY...AS SFC LOW PUSHES OFF THE COAST NR THE SOUTHERN DELMARVA. MDL SOUNDINGS IMPLY PERSISTENT CLOUDINESS THRU MUCH OF FRIDAY ACROSS THE SOUTHERN COUNTIES...WHERE MOIST EASTERLY FLOW WILL LINGER. ACROSS NORTHERN PA...A MUCH BRIGHTER DAY EXPECTED. GEFS MEAN 925/850 TEMPS SUPPORT MAX TEMPS BTWN 75-80F. GENERALLY FAIR AND SEASONABLE WX EXPECTED THIS WEEKEND...AS CENTRAL PA WILL BE IN REGION OF LG SCALE SUBSIDENCE ON EAST SIDE OF UPPER RIDGE OVR THE MISS VALLEY. WILL PAINT A SLIGHT CHC OF PM SHRA/TSRA SUNDAY TO ACCOUNT FOR PASSAGE OF WEAK SHORTWAVE RIDING N PERIPHERY OF MISS VALLEY UPPER RIDGE. GEFS PLUMES INDICATE A GRADUAL WARMING TREND INTO THE WEEKEND...WITH READINGS CLOSE TO AVERAGE FOR EARLY AUGUST. SOME TIMING DIFFS HAVE ARISEN WITH ANTICIPATED COLD FRONT EARLY NEXT WEEK. HAVE SIDED WITH THE GEFS/ECENS AND OPER CANADIAN...ALL OF WHICH INDICATE A FROPA LATE MONDAY/EARLY TUE...AS OPPOSED TO THE OPER ECMWF...WHICH IS 12-24HRS SLOWER AND IMPLIES A DRY MONDAY. HAVE INCREASED CHC OF SHRA/TSRA MON PM...AS HGTS FALL AHEAD OF APPROACHING TROF AND A SURGE OF HIGHER PWATS WORK INTO THE REGION ON SW FLOW. DEEPENING TROUGH AND SLOWING COLD FRONT WILL LKLY RESULT IN LINGERING SHRA/TSRA INTO TUESDAY. GEFS AND EC BOTH CURRENTLY INDICATE THE POSSIBILITY OF HVY RAINFALL ACROSS EASTERN PA ASSOC WITH THIS SLOWING FRONT. COOLER/DRIER WX IS LIKELY BY MIDWEEK. HOWEVER...UPPER TROF/COOL MID LVL TEMPS OVR THE REGION COULD PROMOTE PM SHOWERS...ESP OVR THE MTNS. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... M/CLR SKIES WITH HIGH CI INCR FROM W TO E. IFR FOG PSBL AT BFD BUT CONFIDENCE IN SUSTAINED IFR IS LOW THEREFORE CUT BACK TO TEMPO 3SM BR SCT001. LOW PRESSURE WILL TRACK EWD FROM THE MID MS/LOWER OH VALLEYS INTO THE SRN MID ATLC STATES ON FRIDAY AND OFF THE EAST COAST ON SAT. HIGH PRESSURE/VFR WILL MOVE INTO THE AIRSPACE BEHIND THE DEPARTING SFC LOW. THE GREATEST RISK FOR RAIN/SUB-VFR CIGS WILL BE ACROSS THE SRN 1/3 OF THE AIRSPACE TONIGHT INTO EARLY FRIDAY. CONFIDENCE IS LOW AND THEREFORE KEPT CIGS AOA 050. OUTLOOK... SAT-SUN...PATCHY A.M. FOG/VFR. MON...VFR WITH CHC OF TSTMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...FITZGERALD/STEINBUGL SHORT TERM...STEINBUGL LONG TERM...FITZGERALD AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
419 AM EDT THU AUG 6 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK TO THE SOUTH OF PENNSYLVANIA THROUGH THE END OF THE WEEK AND MOVE OFFSHORE THIS WEEKEND. HIGH PRESSURE WILL MOVE INTO THE AREA BEHIND THE DEPARTING LOW. RAIN IS LIKELY NEAR THE MASON DIXON LINE THIS AFTERNOON INTO TONIGHT BEFORE CONDITIONS DRY OUT FOR THE MOST PART ON FRIDAY. && .NEAR TERM /UNTIL NOON TODAY/... PATCHY FOG ACROSS THE NORTHERN TIER WILL DISSIPATE AROUND 12Z. HIGH-TO-MID CLOUDS WILL INCREASE FROM SW TO NE THROUGH MID DAY IN ADVANCE OF WELL DEFINED MID/UPPER LEVEL SYSTEM /FOR THIS TIME OF YEAR/ AND DEVELOPING SFC LOW OVER THE MID MS/LOWER OH VALLEY. SFC HIGH EXTENDING SEWD FROM THE UPPER GREAT LAKES AND LOW PW AIR WILL KEEP DRY WX INTACT THIS MORNING. && .SHORT TERM /NOON TODAY THROUGH 6 AM FRIDAY/... SHORT TERM MODELS ARE IN GOOD AGREEMENT IN TAKING THE H5 HEIGHT FALL CENTER AND SFC REFLECTION TO THE SOUTH OF CENTRAL PA THROUGH THE PERIOD...FROM KY EWD ACROSS THE CENTRAL APPALACHIANS AND INTO THE SRN MID ATLC. HOWEVER...THERE CONTINUES TO BE SOME UNCERTAINTY WITH RESPECT TO THE QPF DISTRIBUTIONS/WARM SEASON OVERRUNNING SCENARIO TO THE NORTH OF THE SFC WAVE. FOR THIS REASON STAYED PRETTY CLOSE TO A BLENDED SOLUTION WITH WPC QPF...WHICH LEANED TOWARD THE HI RES MODELS. THE FINAL NDFD FCST WILL SHOW AN INCREASE IN POPS OVER THE FAR SRN TIER ZONES FROM THE PA TURNPIKE SWD TO THE MASON DIXON LINE. THE LATEST HRRR AND 00Z SSEO ARE STRADDLING THE PA/MD LINE WITH SHOWER ACTIVITY THRU 18-21Z TIME FRAME. THERE SHOULD BE A FAIRLY SHARP GRADIENT TO THE NRN EDGE OF THE RAIN AND MODELS MAY BE TOO BULLISH ON WAA/OVERRUNNING COMPONENT IN LIEU OF CONVECTION FARTHER TO THE SOUTH. LATER SHIFTS MAY NEED TO MAKE N-S ADJUSTMENTS IN P0PS/QPF AS THE PCPN PATTERN EVOLVES THROUGH EARLY TONIGHT. POPS WILL TREND LOWER FROM NW TO SE INTO EARLY FRIDAY WITH M/CLR SKIES/PATCHY FOG OVER THE NW MTNS BY FRIDAY MORNING. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... SEVERAL SUCCESSIVE LOWS MOVING THROUGH CANADA WILL DOMINATE THE WEATHER PATTERN THROUGH THE MID TO LONG TERM. MINOR DIFFERENCES REMAIN REGARDING EXACT TRACK OF SFC LOW PASSING SOUTH OF PA THURSDAY NIGHT INTO EARLY FRIDAY. LOOKS LIKE THE SOUTHERN TIER COUNTIES WILL BE ON NORTHERN PERIPHERY OF THE PRECIP..SO WILL MENTION CHC/SCHC OF SHOWERS ACROSS THE SOUTHERN THIRD OF THE STATE THRU FRIDAY AM. BEHIND THIS SYSTEM...ODDS NOW APPEAR TO FAVOR FAIR AND SEASONABLE WX THIS WEEKEND...AS CENTRAL PA WILL BE IN REGION OF LG SCALE SUBSIDENCE ON EAST SIDE OF UPPER RIDGE OVR THE MISS VALLEY. GEFS TEMP PLUMES INDICATE A GRADUAL WARMING TREND INTO THE WEEKEND...AS HGTS RISE ACROSS PA. MED RANGE GUIDANCE EXHIBITING RELATIVELY LITTLE SPREAD WITH MASS FIELDS INTO NEXT WEEK...LENDING CONFIDENCE IN A COLD FRONTAL PASSAGE AND ROUND OF SHRA/TSRA ARND NEXT TUESDAY. && .AVIATION /08Z THURSDAY THROUGH MONDAY/... M/CLR SKIES WITH HIGH CI INCR FROM W TO E. IFR FOG PSBL AT BFD BUT CONFIDENCE IN SUSTAINED IFR IS LOW THEREFORE CUT BACK TO TEMPO 3SM BR SCT001. LOW PRESSURE WILL TRACK EWD FROM THE MID MS/LOWER OH VALLEYS INTO THE SRN MID ATLC STATES ON FRIDAY AND OFF THE EAST COAST ON SAT. HIGH PRESSURE/VFR WILL MOVE INTO THE AIRSPACE BEHIND THE DEPARTING SFC LOW. THE GREATEST RISK FOR RAIN/SUB-VFR CIGS WILL BE ACROSS THE SRN 1/3 OF THE AIRSPACE TONIGHT INTO EARLY FRIDAY. CONFIDENCE IS LOW AND THEREFORE KEPT CIGS AOA 050. OUTLOOK... SAT-SUN...PATCHY A.M. FOG/VFR. MON...VFR WITH CHC OF TSTMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...FITZGERALD/STEINBUGL SHORT TERM...STEINBUGL LONG TERM...FITZGERALD/CERU AVIATION...STEINBUGL
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1120 PM MDT WED AUG 5 2015 .UPDATE... ISSUED AT 821 PM MDT WED AUG 5 2015 00Z KUNR SOUNDING SHOWED DECENT SUPPORT FOR WIND...WHICH DID OCCUR WITH CONVECTION WEST OF RAPID CITY. WATER VAPOUR SHOWED RESPONSIBLE SHORTWAVE PLOWING NORTHEAST FROM WY INTO THE DAKOTAS. SECONDARY WAVE NOTED ACROSS NORTHWEST WY...WHICH THE 00Z GUIDANCE PICKS UP ON AND MOVES NORTHEAST INTO ND OVERNIGHT. TAIL END OF WAVE MAY PRODUCE ANOTHER ROUND OF -SHRA/-TSRA ACROSS THE CWA LATER THIS EVENING BEHIND INITIAL WAVE WHICH IS MOVING ONTO THE SD PLAINS. STRENGTH OF MUCAPE SLOWLY WANES OVERNIGHT. FORECAST TWEAKED FOR TIMING...BUT LARGELY IN GOOD SHAPE. && .SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT ISSUED AT 218 PM MDT WED AUG 5 2015 UPPER WAVE CONTINUES TO APPROACH THE REGION...AS UPPER LOW CIRCULATES OVER SOUTHWEST CANADA. WEAK SHOWERS ACROSS NORTHEAST WYOMING HAVE BEEN DISSIPATING AS THEY MOVE EASTWARD...WITH JUST SOME CLOUDS PUSHING INTO THE CWA. WITH LIGHT AND VARIABLE WINDS...TEMPS ARE GENERALLY IN THE 80S. SHOWERS AND THUNDERSTORMS STILL EXPECTED TO DEVELOP ALONG A LINE OF FRONTOGENESIS/Q-VECTOR CONVERGENCE ACROSS THE WESTERN CWA AND EXPAND EASTWARD. MODELS ARE HINTING AT AN INITIAL WAVE WITH BEST FORCING JUST NORTHWEST OF THE CWA BRINGING A BAND OF STORMS THROUGH THE NORTHERN HILLS AND NORTHWESTERN SD...WITH A SECONDARY WAVE IMMEDIATELY FOLLOWING WITH SCATTERED SHOWERS/STORMS. HRRR THIS MORNING WAS PRETTY CONSISTENT WITH A SQUALL LINE MOVING ACROSS THE NORTHERN HILLS AND NORTHWEST SD EARLY THIS EVENING...BUT LATER RUNS ARE SHOWING A MORE SCATTERED FORM. MLCAPE IS UNIMPRESSIVE AROUND 750 J/KG ON THE PLAINS WITH 1500 J/KG OVER THE HILLS...BUT SHEAR IS 35-45 KTS SO WOULD NOT RULE OUT A STRONG TO SEVERE STORM. MAIN THREAT WILL BE STRONG WINDS. SURFACE LOW WILL MOVE ACROSS SD THURSDAY. A TIGHT PRESSURE GRADIENT BEHIND THE LOW WILL CREATE SOME BREEZY NORTHWEST WINDS ACROSS THE SD PLAINS AND ALSO BRING IN SOME COOLER AIR TO NORTHWESTERN SD. SHOWERS/THUNDERSTORMS WILL CONTINUE ACROSS NORTHWESTERN/CENTRAL SD DURING THE DAY UNTIL THE WAVE FINALLY TRANSITIONS EASTWARD OUT OF THE REGION. DRY WEATHER IS THEN EXPECTED FOR THURSDAY NIGHT. HIGHS THURSDAY WILL BE IN THE 80S...70S IN THE BLACK HILLS. .LONG TERM...FRIDAY THROUGH WEDNESDAY ISSUED AT 218 PM MDT WED AUG 5 2015 PROGRESSIVE FLOW WILL CONTINUE THROUGH THE WEEKEND WITH A STRONGER UPPER LEVEL TROUGH ON TRACK FOR SAT-SUN. HOWEVER...STRONG INDICATIONS ARE IN PLACE FOR SIG LONG WAVE RIDGING OVER CENTRAL NOAM EARLY NEXT WEEK WHICH WOULD SUPPORT A MUCH WARMER PERIOD FOR THE REGION BY THE MIDDLE OF NEXT WEEK. HIGHEST POPS IN THE PERIOD ARE IN THE SAT-SUN PERIOD AS THE CURRENT UPPER LOW OFF THE COAST OF CA EJECTS NE ACROSS THE ROCKIES AND INTO THE REGION. PLENTY OF LL MOISTURE WILL BE IN PLACE WITH INCREASING LARGE SCALE ASCENT AND MONSOON MOISTURE TO SUPPORT SCT SHRA/TS IN THIS PERIOD ESP ACROSS THE NORTHERN ZONES. LINGERING CHANCES FOR PRECIP SUNDAY NIGHT WITH DRY WEATHER EXPECTED EARLY NEXT WEEK...PERHAPS A SLIGHT CHANCE OF A TS OVER THE BLACK HILLS TUES WHEN BETTER MOISTURE RETURNS TO THE AREA AHEAD OF A LEE TROUGH. SOME SEVERE THREAT WILL BE IN PLACE SAT/SUN WITH INCREASING FLOW SUPPORTING DECENT BULK SHEAR /0-6KM/ NUMBERS ABOVE 35 KNOTS...WITH 1-2 KJ/KG OF CAPE OVER THE SE FA. HOWEVER...STILL MUCH UNCERTAINTY PER SYSTEM TRACK/SPEED TO ASCERTAIN A BETTER GRASP ON SEVERE PROBS. AFTER A SEASONAL DAY FRIDAY...COOLER TEMPS ARE ON TRACK FOR THE WEEKEND...WITH A MODEST COOL DOWN EXPECTED SUNDAY.. MUCH WARMER WEATHER ON TRACK FOR TUE AND BEYOND WITH 90S EXPECTED. A FEW 100/S A CERTAINLY NOT OUT OF THE QUESTION...ESP ON THE SD PLAINS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1119 PM MDT WED AUG 5 2015 SCATTERED TSRA WILL MOVE ACROSS THE AREA TONIGHT...CLEARING OUT FROM WEST TO EAST EARLY THURSDAY MORNING AS A FRONTAL BOUNDARY MOVES THROUGH. GUSTY WEST/NORTHWEST WINDS EXPECTED ON THE PLAINS BEHIND THE BOUNDARY TOMORROW. LOCAL IFR CONDITIONS EXPECTED WITH THE STORMS...BUT VFR CONDITIONS OTHERWISE WILL PREVAIL. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...HELGESON SHORT TERM...POJORLIE LONG TERM...JC AVIATION...HELGESON
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
357 AM CDT THU AUG 6 2015 .SHORT TERM... UPPER LEVEL HIGH PRESSURE WILL CONTINUE TO EXPAND ACROSS THE AREA TODAY AND TONIGHT. THIS WILL LEAD TO BETTER SURFACE WARMING WITH HIGHS TODAY A DEGREE OR MAYBE TWO WARMER FOR MOST OF THE AREA...AND SHOULD BE THE HOTTEST DAY OF SUMMER SO FAR. SURFACE MOISTURE STILL ELEVATED THOUGH WILL TREND DOWNWARDS DURING THE PEAK MIXING PERIOD THIS AFTERNOON...SO WILL ALSO LIMIT HEAT INDEX VALUES SOMEWHAT. WE REMAIN A BIT UNCERTAIN IF MODELS ARE CORRECTLY FORECASTING SURFACE DEWPOINT VALUES...AND IF UNDERPLAYED BY ONLY 2 OR 3 DEGREES MAY REQUIRE CONSIDERATION OF A HEAT ADVISORY IN THE SOUTHEAST CORNER OF OUR AREA. BUT FOR NOW WE SIDE WITH THE BULK OF OUR GUIDANCE WHICH COMES UP JUST SHORT OF HEAT ADVISORY LEVELS. WHILE THE UPPER RIDGE WILL CONTINUE TO EXPAND...CAPPING STILL LOOKS MARGINAL AND ACTUALLY FORECAST TO WEAKEN DURING PEAK DEEP MIXING ACROSS THE NORTHWEST CORNER OF OUR AREA. A SHORT WAVE PASSING BY TO THE NORTH WILL DRAG ANOTHER BATCH OF LIMITED MID LEVEL MOISTURE ACROSS THIS AREA THIS AFTERNOON AND EARLY EVENING. A SURFACE TROUGH ALSO WILL PROVIDE WEAK CONVERGENCE IN OUR NORTHWEST. SHORT RANGE SOLUTIONS OF RAP AND HRRR HAVE ONCE AGAIN BEEN INSISTENT TONIGHT ON ISOLATED TO WIDELY SCATTERED COVERAGE OF HIGH-BASED THUNDERSTORMS LATE THIS AFTERNOON INTO THE EARLY EVENING...ALTHOUGH LESS COVERAGE THAN EXPERIENCED YESTERDAY. SURFACE BASED CAPES APPEAR MOSTLY UNDER 1000 JOULES PER KILOGRAM LATER TODAY SO STORMS MAY HAVE A LITTLE LESS OOMPH AS WELL. EVEN SO...WE WILL INCLUDE A SLIGHT CHANCE FOR THUNDERSTORMS FOR LATER THIS AFTERNOON AND EARLY THIS EVENING IN OUR NORTHWEST CORNER. ANY STORMS SHOULD QUICKLY DISSIPATE WITH LOSS OF SURFACE HEATING EARLY THIS EVENING AND ANOTHER QUIET AND MILD NIGHT WILL FOLLOW. RMCQUEEN .LONG TERM... FRIDAY AND INTO THE WEEKEND WILL REMAIN HOT...ALTHOUGH A COUPLE OF DEGREES COOLER THAN TODAY AS THE UPPER HIGH IS NUDGED EAST AHEAD OF A DISTURBANCE PUSHING ONSHORE CENTRAL CALIFORNIA. HIGH TEMPERATURES WILL REMAIN MOSTLY IN THE MID 90S TO NEAR THE CENTURY MARK ON THE CAPROCK WHILE LOCALES IN THE ROLLING PLAINS AND FAR SOUTHEAST PANHANDLE RESIDE IN THE UPPER 90S TO AROUND 104-105 DEGREES. LATE SUNDAY CONTINUES TO BEAR WATCHING IN TERMS OF ISOLATED THUNDERSTORM POTENTIAL NEAR THE FAR SOUTHWEST PANHANDLE INTO THE NORTHERN SOUTH PLAINS. ENERGY FROM THE PREVIOUSLY MENTIONED DISTURBANCE...AT THIS TIME ROTATING THROUGH THE NORTHERN PLAINS INTO THE UPPER MIDWEST...WILL SEND A FRONTAL BOUNDARY SOUTHWARD THROUGH THE PLAINS. AT THE SAME TIME...A SUBTROPICAL MOISTURE PLUME WILL ATTEMPT TO BEND EASTWARD ACROSS THE TEXAS/NEW MEXICO BORDER. WHETHER THIS ENHANCED MID-UPPER MOISTURE MAKES IT INTO THE LONE STAR STATE WILL DEPEND ON PLACEMENT OF THE UPPER HIGH AS LATER SUNDAY LOOKS TO BE THE TIME AT WHICH THIS FEATURE BEGINS RETROGRADING WESTWARD. BELIEVE ENOUGH CONSISTENCY HAS BEEN SHOWN AT THIS TIME TO WARRANT SLIGHT CHANCE MENTION ACROSS PARMER COUNTY...BUT WILL CONTINUE TO MONITOR SAID UNCERTAINTIES GOING FORWARD. HEADING INTO NEXT WEEK...UPPER HIGH STILL LOOKS TO BUILD WEST AND NORTHWEST WHILE AMPLIFYING...THUS SHIFTING THE H85 THERMAL RIDGE AXIS IN THE SAME DIRECTION AND KEEPING TEMPERATURES MAINLY IN THE 90S LOCALLY. CYCLONIC FLOW FROM EASTERN CANADA BACK INTO THE OHIO VALLEY LOOKS TO KEEP SOME SEMBLANCE OF A FRONTAL BOUNDARY IN PLACE AHEAD OF A SURFACE RIDGE PUSHING SOUTH THROUGH THE MISSISSIPPI VALLEY. NWP NOW SUGGESTING THAT A PERIOD OF CONTINUED UPSLOPE FLOW MAY THEREFORE BE IN THE OFFING FOR A PERIOD NEXT WEEK ALONG WITH CONTINUED ENHANCED MOISTURE TRAPPED UNDERNEATH THE UPPER HIGH. HAVE KEPT CONDITIONS DRY FOR NOW AFTER SUNDAY EVENING GIVEN THE UNCERTAINTY IN THE DETAILED SYNOPTIC EVOLUTION AND EXTENT/AMOUNT OF MOISTURE THAT WILL BE AVAILABLE. THUNDERSTORM CHANCES AND COOLER TEMPERATURES WOULD BE THE SENSIBLE WEATHER RESULTS IF THIS SCENARIO DOES INDEED PLAY OUT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 99 69 97 67 / 10 0 0 0 TULIA 99 70 98 69 / 10 10 0 0 PLAINVIEW 100 71 98 70 / 10 10 0 0 LEVELLAND 101 71 99 70 / 10 0 0 0 LUBBOCK 100 74 100 72 / 0 0 0 0 DENVER CITY 102 70 99 70 / 0 0 0 0 BROWNFIELD 101 71 99 71 / 0 0 0 0 CHILDRESS 104 76 104 75 / 0 0 0 0 SPUR 103 75 102 73 / 0 0 0 0 ASPERMONT 106 78 104 77 / 0 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/31
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
940 AM EDT THU AUG 6 2015 .DISCUSSION... TODAY...EARLY MORNING BUOY REPORTS AT 41009 AND 41010 SHOWED SOUTHWEST WINDS WHILE SPGF1 REPORTED A SOUTHEAST WIND. THIS DEPICTS A NARROW SURFACE RIDGE OVER OUR SOUTHERN SECTIONS. THE RIDGE WILL NUDGE SOUTH THOUGH AS A FRONTAL TROUGH SAGS INTO THE SOUTHEAST STATES. THE RESULTANT SOUTHWEST FLOW LOOKS LIGHT ENOUGH FOR A SEA BREEZE EXCEPT NORTH OF THE CAPE. MORNING SOUNDINGS INDICATED RATHER AVERAGE LOOKING LAPSE RATES FOR THIS TIME OF THE YEAR WITH 500 MB TEMPS AROUND MINUS 6 DEGREES CELSIUS. PRECIPITABLE WATER WAS 1.8 TO 1.9 INCHES ACROSS CENTRAL FLORIDA BUT MIAMI AND KEY WEST SHOWED A SUBSIDENCE INVERSION NEAR 850MB WITH DRYING ABOVE. THE LOCAL FORECAST OFFICES THERE HAVE NOTED THIS DRY LAYER IS DUE TO AN INTRUSION OF SAHARAN AIR. GPS PRECIPITABLE WATER DATA SUGGESTS THAT SOME OF THIS DRIER AND MORE STABLE AIR COULD AFFECT OUR SOUTHERN SECTIONS AND THE RAP FORECAST SOUNDINGS CONFIRM A DRY LAYER FROM ABOUT VRB SOUTHWARD. WITH THIS IN MIND AND ALSO THAT THE LAKE OKEECHOBEE SHADOW WILL SHIFT CLOCKWISE TO AFFECT THE TREASURE COAST TODAY...WILL PLAN ON TWEAKING POPS DOWN A LITTLE OVER THE SOUTH COAST. INTERESTINGLY... THE 12Z LOCAL WRF AND HRRR MODELS SUGGEST THAT THE NORTH OKEECHOBEE BOUNDARY WILL PROVIDE INITIAL FOCUS FOR CONVECTION THIS AFTERNOON... WITH ST LUCIE AND MARTIN COUNTIES MUCH LESS ACTIVE. THE MESOSCALE MODELS DO NOT GENERATE VERY MUCH CONVECTION ACROSS THE NORTH...BUT CONFIDENCE IS NOT HIGH ENOUGH AT THIS TIME TO MAKE ANY CHANGES TO THE 40 PERCENT POPS THERE. && .AVIATION...VFR THIS MORNING (WITH A LITTLE HAZE ALOFT NOTED AT SOUTHERN TERMINALS AROUND KSUA). MAIN CHALLENGE WILL BE COVERAGE AND TIMING OF AFTERNOON STORMS. THE RIDGE AXIS POSITION SHIFTING SOUTH OF OKEECHOBEE WILL PLACE MOST OF EAST CENTRAL FLORIDA IN A MORE FAVORED MOISTURE CONVERGENCE ZONE. BUT PRESENTLY...THE LIMITED DEEP CONVECTION IN THE GULF AND ATLANTIC...SUGGESTS THAT COVERAGE WILL BE SCATTERED. THIS LOOKS REASONABLE GIVEN THE RATHER AVERAGE LOOKING LAPSE RATES (THAT ARE TYPICAL FOR THIS TIME OF THE YEAR) AND THE FACT THAT MOISTURE...WHILE RUNNING A LITTLE ABOVE CLIMO IN MOST AREAS...IS NOT "SOUPY" BY ANY MEANS. && .MARINE... TODAY...SURFACE RIDGE AXIS SHOULD NUDGE INTO SOUTH FLORIDA BUT PRESSURE GRADIENT LOOKS TO ONLY SUPPORT 10 KNOT SOUTHWEST WINDS... WHICH WILL BE LIGHT ENOUGH FOR A SEA BREEZE FROM ABOUT THE CAPE SOUTHWARD. THE MAIN MARINER CONCERN WILL BE SCATTERED AFTERNOON STORMS OVER THE MAINLAND THAT PUSH ACROSS THE COAST AS STEERING LEVEL WINDS HAVE INCREASED. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM...LASCODY IMPACT WX....SEDLOCK
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
922 AM CDT THU AUG 6 2015 ...UPDATE TO SYNOPSIS... .SYNOPSIS... ISSUED AT 920 AM CDT THU AUG 6 2015 WV Imagery and 12Z upper air analysis indicate a weak upper level ridge of high pressure situated across the Desert Southwest. Meanwhile, an upper level trough of low pressure is moving eastward across the Northern Rockies. Near the surface, a near stationary frontal boundary extends east from the Texas panhandle into western Oklahoma. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 328 AM CDT THU AUG 6 2015 A weak shortwave trough was approaching the northern plains today. Surface troughing will develop ahead of this feature across the northern plains. A plume of warm air at 700mb will be shunted eastward across the plains. Meanwhile, a weak surface low, partially thermal in nature, will develop over the Oklahoma Panhandle. A warm front will extend eastward from this low near the Oklahoma/Kansas border. Low level upslope flow north of this front will result in very humid conditions today except for the extreme southwest corner where veered surface winds will allow the lower levels to dry out. Temperatures will be held down by the moist upslope flow across most of southwest Kansas, with highs in the upper 80s to mid 90s. However, temperatures may exceed 100F in Elkhart. There is a very small chance of an isolated thunderstorm near a weak wind shift line from Hugoton northward to Scott City as surface based CAPE values may exceed 4000 j/kg. However, given the strong capping ahead of the surface trough, any storm that attempts to develop out in far western Kansas would quickly move into a strongly capped environment given a 30 mph storm motion to the southeast. Bottom line is that thunderstorms probably will not develop. Temperatures may reach close to heat advisory criteria near the Oklahoma state line this afternoon. .LONG TERM...(Friday THROUGH Wednesday) ISSUED AT 328 AM CDT THU AUG 6 2015 A minor shortwave trough will pass across the central plains on Friday as the aforementioned surface front edges northward into northern Kansas. Thunderstorms are possible across western Kansas in the late afternoon and evening but could stay north of Interstate 70. Another minor shortwave trough will approach western Kansas late Saturday with additional small chances for thunderstorms in the late afternoon and evening. High temperatures ought to warm into the mid to upper 90s Friday and Saturday in the warm sector, particularly from Garden City and Dodge City southward to the Oklahoma state line Saturday and across all of western Kansas on Sunday. A shortwave trough traversing the northern plains on Sunday will push a cold front into western Kansas late in the day. There is a chance of thunderstorms along this front. Cooler weather can be expected Monday and Tuesday in the wake of the front, but there is still a small chance of thunderstorms on the cool but moist side of the front. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Friday MORNING) ISSUED AT 603 AM CDT THU AUG 6 2015 Latest satellite and surface observations indicating IFR/LIFR stratus increasing across western Kansas early this morning. The latest RAP and HRRR also appears to have a decent handle with this stratus based on 11z Thursday verification. will therefore follow the general trend of the HRRR and RAP and begin the 12z tafs with IFR/LIFR conditions at DDC, GCK, and HYS. This stratus to linger through 15z and then begin to dissipate. VFR conditions are expected at all three taf sites by 18z. The winds will be southeasterly at 10 knots or less. && .PRELIMINARY POINT TEMPS/POPS... DDC 92 70 97 72 / 0 0 0 10 GCK 92 68 97 71 / 10 0 0 20 EHA 101 68 100 71 / 0 0 0 20 LBL 100 70 98 73 / 0 0 0 10 HYS 91 68 95 71 / 0 0 0 30 P28 93 73 98 75 / 0 0 0 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JJohnson SHORT TERM...Finch LONG TERM...Finch AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
604 AM CDT THU AUG 6 2015 ...Updated aviation discussion... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 328 AM CDT THU AUG 6 2015 A weak shortwave trough was approaching the northern plains today. Surface troughing will develop ahead of this feature across the northern plains. A plume of warm air at 700mb will be shunted eastward across the plains. Meanwhile, a weak surface low, partially thermal in nature, will develop over the Oklahoma Panhandle. A warm front will extend eastward from this low near the Oklahoma/Kansas border. Low level upslope flow north of this front will result in very humid conditions today except for the extreme southwest corner where veered surface winds will allow the lower levels to dry out. Temperatures will be held down by the moist upslope flow across most of southwest Kansas, with highs in the upper 80s to mid 90s. However, temperatures may exceed 100F in Elkhart. There is a very small chance of an isolated thunderstorm near a weak wind shift line from Hugoton northward to Scott City as surface based CAPE values may exceed 4000 j/kg. However, given the strong capping ahead of the surface trough, any storm that attempts to develop out in far western Kansas would quickly move into a strongly capped environment given a 30 mph storm motion to the southeast. Bottom line is that thunderstorms probably will not develop. Temperatures may reach close to heat advisory criteria near the Oklahoma state line this afternoon. .LONG TERM...(Friday THROUGH Wednesday) ISSUED AT 328 AM CDT THU AUG 6 2015 A minor shortwave trough will pass across the central plains on Friday as the aforementioned surface front edges northward into northern Kansas. Thunderstorms are possible across western Kansas in the late afternoon and evening but could stay north of Interstate 70. Another minor shortwave trough will approach western Kansas late Saturday with additional small chances for thunderstorms in the late afternoon and evening. High temperatures ought to warm into the mid to upper 90s Friday and Saturday in the warm sector, particularly from Garden City and Dodge City southward to the Oklahoma state line Saturday and across all of western Kansas on Sunday. A shortwave trough traversing the northern plains on Sunday will push a cold front into western Kansas late in the day. There is a chance of thunderstorms along this front. Cooler weather can be expected Monday and Tuesday in the wake of the front, but there is still a small chance of thunderstorms on the cool but moist side of the front. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Friday MORNING) ISSUED AT 603 AM CDT THU AUG 6 2015 Latest satellite and surface observations indicating IFR/LIFR stratus increasing across western Kansas early this morning. The latest RAP and HRRR also appears to have a decent handle with this stratus based on 11z Thursday verification. will therefore follow the general trend of the HRRR and RAP and begin the 12z tafs with IFR/LIFR conditions at DDC, GCK, and HYS. This stratus to linger through 15z and then begin to dissipate. VFR conditions are expected at all three taf sites by 18z. The winds will be southeasterly at 10 knots or less. && .PRELIMINARY POINT TEMPS/POPS... DDC 92 70 96 72 / 0 0 10 10 GCK 92 69 96 71 / 10 10 10 20 EHA 101 69 99 71 / 0 10 20 20 LBL 100 70 97 73 / 0 0 10 10 HYS 91 68 94 71 / 0 10 10 30 P28 93 73 97 75 / 0 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Finch LONG TERM...Finch AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
649 AM EDT THU AUG 6 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 435 AM EDT THU AUG 6 2015 UPPER GREAT LAKES IS WITHIN WESTERLY FLOW ALOFT BETWEEN LARGE UPPER LOW OVER EASTERN CANADA AND UPPER TROUGH OVER FAR WESTERN CANADA. COUPLE OF MAIN SHORTWAVES ARE UPSTREAM OF UPPER GREAT LAKES. THE LEAD WAVE IS OVER SOUTHERN MANITOBA AND IS GENERATING CLUSTER OF SHRA/TSRA SOUTHERN MANITOBA INTO NORTHWEST MINNESOTA. WARM AIR ADVECTION MAINLY IN THE MID LEVELS IS SUPPORTING ARC OF LGT SHRA TOWARD ISLE ROYALE AND NORTHERN LK SUPERIOR. BASED ON HRRR AND RAP AND CURRENT RADAR TRENDS...COULD SEE ISOLD SHR OR SPRINKLES CLIP TIP OF KEWEENAW PENINSULA THIS MORNING. OTHERWISE...MAIN EFFECT FM THIS SHORTWAVE WILL BE A LOT OF MID CLOUDS OVER AT LEAST NORTHERN CWA MOST OF TODAY. SINCE THERE ARE ALREADY A WIDESPREAD AREA OF 5-10KFT BKN CIGS UPSTREAM IN MINNESOTA...BUMPED UP CLOUD COVER TODAY. SOUTHERN CWA SHOULD STAY IN AT LEAST INTERVALS OF SUN AND CLOUDS SO WENT WARMEST THERE WITH MID 70S NEAR WI BORDER. COOLEST READINGS IN THE UPR 60S TO NEAR 70 DEGREES WILL BE CLOSER TO LK SUPERIOR WITH MORE CLOUD COVER AND EAST-SOUTHEAST ONSHORE GRADIENT WINDS. FOR TONIGHT...ATTN TURNS TO SHORTWAVE CURRENTLY OVER WY AND SD. THIS SHORTWAVE MOVES ACROSS NORTHERN PLAINS AND ARRIVES OVER CNTRL MN AND WESTERN WI BY LATE TONIGHT. BULK OF STRONGER Q-VECTOR CONVERGENCE STAYS OUT AHEAD OF THAT SHORTWAVE...BUT AS ASSOCIATED SFC LOW WITH THE WAVE MOVES OVER MN...STRONG MOISTURE ADVECTION AT H85 ALONG WITH ISENTROPIC LIFT 300-305K /H9-H7/ SHOULD SUPPORT INCREASING SHOWERS INTO WESTERN UPR MICHIGAN AFTER MIDNIGHT. POPS RAMP UP TO HIGHER CHANCE AT KIWD AFTER MIDNIGHT WITH SLIGHT CHANCES AS FAR EAST AS ISHPEMING AND IRON MOUNTAIN. MUCAPE IN LOWEST 3KM OR APPROX SFC-H7 STAYS MAINLY SOUTHWEST OF CWA. ISOLD TSRA COULD SNEAK INTO FAR WEST AS MODEST LOW-LEVEL JET MAY COULD ADVECT SMALL PORTION OF INSTABILITY INTO CWA...BUT WILL KEEP TSRA OUT OF CWA THROUGH 12Z FRIDAY. MIN TEMPS MUCH WARMER THAN LAST COUPLE NIGHTS MID 50S TO LOW 60S DUE TO PLENTY OF CLOUD COVER AND STEADY SOUTH WINDS AHEAD OF THE SFC LOW IN MN. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 347 AM EDT THU AUG 6 2015 NAM SHOWS A SHORTWAVE OVER THE NORTHERN PLAINS 12Z FRI WITH ANOTHER ENTERING INTO THE UPPER GREAT LAKES THEN. THIS SHORTWAVE MOVES THROUGH ON FRI AND THE OTHER SHORTWAVE MOVES SLOWLY EAST AND AFFECTS THE AREA ON SAT. NAM SHOWS SOME 850-500 MB Q-VECTOR CONVERGENCE AND MOISTURE MOVING THROUGH ON FRI AND BOTH MOVE OUT SAT AFTERNOON BEFORE RETURNING SAT NIGHT. CONFIDENCE IS LOW WITH THIS FORECAST AS GFS...ECMWF AND NAM ALL HAVE DIFFERENT IDEAS FOR HOW THIS WEATHER SCENARIO IS GOING TO PLAY OUT. ECMWF IS DRIER AND FURTHER SOUTH WITH IT PCPN. GFS IS QUICKER MOVING PCPN THROUGH. WENT WITH A BLEND OF THE SOLUTIONS WHICH SEEMED TO KEEP SOME CONTINUITY TO THE FORECAST. LOOKS LIKE THERE WILL BE A BREAK IN PCPN FOR LATE FRI NIGHT INTO SAT MORNING AND THEN ANOTHER WAVE COMES IN AND TRIED TO REFLECT THIS IN THE FORECAST WITH A BREAK IN THE PCPN. BEST CHANCE FOR PCPN APPEARS TO BE FRI INTO FRI EVENING...THEN HAVE LOW CHANCE POPS AND LOW CONFIDENCE FOR SAT AND SAT NIGHT. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE OVER THE SOUTHERN AND CENTRAL PLAINS 12Z SUN WITH A TROUGH ACROSS CENTRAL CANADA AND A SHORTWAVE IN THE NORTHERN PLAINS. THIS SHORTWAVE HEADS EAST INTO THE UPPER GREAT LAKES SUN NIGHT INTO MON. THIS SHORTWAVE HEADS OVER THE TOP OF THE RIDGE ON MON AND PUSHES IT BACK INTO THE NORTHERN ROCKIES. THE UPPER FLOW BECOMES MORE AMPLIFIED ON TUE WITH THE RIDGE BUILDING INTO THE CANADIAN ROCKIES AND THE TROUGH DIGGING INTO THE ERN U.S. THE RIDGE BUILDS INTO THE NORTHERN PLAINS 12Z WED. SFC RIDGING MOVES INTO THE UPPER GREAT LAKES TUE AND REMAINS INTO WED. TEMPERATURES WILL CONTINUE TO BE SLIGHTLY BELOW NORMAL FOR THIS FORECAST PERIOD. AS THE SFC HIGH BUILDS IN FOR MONDAY...WENT DRY FOR MON NIGHT THROUGH WED AND REMOVED POPS FOR THAT TIME PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 647 AM EDT THU AUG 6 2015 LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE TONIGHT. COULD SEE SHOWERS TOWARD DAYBREAK FRIDAY AT KIWD...BUT WEATHER SHOULD STAY MAINLY DRY AT KCMX AND KSAW. THOUGH A LOT OF MID CLOUDS ARE EXPECTED INTO TONIGHT...CONDITIONS WILL REMAIN VFR. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 435 AM EDT THU AUG 6 2015 A COUPLE OF WEAK TROUGHS OR LOW PRESSURE SYSTEMS WILL MOVE THROUGH THE UPPER GREAT LAKES REGION THROUGH THIS WEEKEND...BUT WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...07 AVIATION...JLA MARINE...SRF
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
850 AM PDT THU AUG 6 2015 .SYNOPSIS...MONSOON MOISTURE WILL PUSH NORTH INTO THE REGION TODAY AND FRIDAY BRINGING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS. THUNDERSTORM ACTIVITY WILL DECREASE RAPIDLY FROM WEST TO EAST FRIDAY AS DRIER AIR PUSHES INTO THE REGION FOR THE WEEKEND. ANOTHER ROUND OF MOISTURE MAY BE ON TAP FOR THE MIDDLE OF NEXT WEEK. && .UPDATE...TWEAKED THE GRIDS THIS MORNING TO ACCOUNT FOR CURRENT CLOUD COVER TRENDS AND NUDGE POPS UPWARDS ALONG THE LOWER COLORADO RIVER VALLEY WHERE LATEST FEW HRRR RUNS BREAK OUT SUBSTANCIAL CONVECTION THIS AFTERNOON. FORECAST SOUNDINGS INDICATE A WELL DEVELOPED INVERTED V PROFILE WHICH WOULD FAVOR LOCALLY STRONG DOWNBURST WINDS WITH ANY SHOWERS AND THUNDERSTORMS WHICH DEVELOP...SO THIS WILL BE WATCHED FOR CLOSELY AS STORMS DEVELOP LATER TODAY. OTHERWISE THE FORECAST IS IN GOOD SHAPE AND NO UPDATES ARE PLANNED. -OUTLER- && .SHORT TERM...TODAY THROUGH FRIDAY NIGHT. LOTS TO MULL OVER WITH THE SHORT TERM FORECAST THIS MORNING. MODELS ARE IN RELATIVELY GOOD AGREEMENT ON THE OVERALL PATTERN EVOLUTION LEADING TO MODERATE-HIGH CONFIDENCE OVERALL. HOWEVER...DIFFERENCES REMAIN IN PRECIPITATION FIELDS...LEADING TO SLIGHTLY LOWER CONFIDENCE IN SHOWER/THUNDERSTORM COVERAGE TODAY AND FRIDAY. TODAY [THROUGH 00Z (5PM)]...TWO MAIN AREAS OF CONCERN EXIST. THE FIRST OVER THE CENTRAL/SOUTHERN MOHAVE COUNTY...EASTERN SAN BERNARDINO COUNTY AND EXTREME SOUTHERN CLARK COUNTY WHERE INCREASING DEEP-LAYER MOISTURE ADVECTION IS EXPECTED TO PERSIST THROUGH THE DAY. BY 00Z PRECIPITABLE WATER VALUES WILL RANGE FROM 1-1.5 INCHES ACROSS THIS AREA. WITH A LACK OF SIGNIFICANT FORCING BEFORE 00Z AND WEAK CAPPING I EXPECT MAINLY TERRAIN-DRIVEN STORMS OVER THIS AREA. STORM MOTION IS EXPECTED TO BE MODEST AT 10-15 KTS TOWARDS THE NORTH- NORTHEAST...HOWEVER TRAINING STORMS (ESPECIALLY OVER THE TERRAIN) ARE A CONCERN WITH CORFIDI VECTORS NEAR ZERO. THE MAIN THREATS WITH THESE STORMS WILL BE DAMAGING WIND GUSTS AND FLASH FLOODING (WHERE STORMS TRAIN). THE OTHER AREA OF CONCERN WILL BE ACROSS THE WESTERN PORTIONS OF SAN BERNARDINO COUNTY WHERE SOME MID-LEVEL MOISTURE AND WEAK MUCAPE COULD LEAD TO ELEVATED CONVECTION DURING THE LATE MORNING INTO THE EARLY AFTERNOON. WITH DRY NEAR-SURFACE CONDITIONS I DON`T EXPECT MUCH RAIN ACCUMULATION...HOWEVER DAMAGING WIND GUSTS AND DRY LIGHTNING ARE A POSSIBILITY. WIDESPREAD OUTFLOW WINDS COULD LEAD TO AREAS OF BLOWING DUST AND LOWERED VISIBILITY. SIMILAR CONDITIONS COULD DEVELOP ACROSS THE HIGHER TERRAIN OF INYO COUNTY LATER IN THE DAY. TONIGHT [00Z (5PM) THROUGH 12Z (5AM)]...MOISTURE ADVECTION WILL CONTINUE...PRIMARILY ACROSS THE EASTERN HALF OF THE FORECAST AREA. A WEAK VORTICITY LOBE IS EXPECTED TO PUSH NORTH-NORTHEAST UP THE COLORADO RIVER VALLEY INTO UTAH OVERNIGHT. THIS WILL COMBINE WITH DIFLUENT FLOW AHEAD OF AN UPPER LEVEL LOW TO TOSS IN SOME ADDITIONAL DYNAMICS INTO A WEAK-MODERATELY UNSTABLE ATMOSPHERE OVERNIGHT AND LIKELY KEEP SOME FORM OF CONVECTION GOING THROUGH THE OVERNIGHT HOURS. PRECIPITABLE WATER VALUES WILL LIKELY REMAIN IN THE 1-1.5 INCH RANGE. STORM MOTION IS EXPECTED TO INCREASE TO 20-25 KTS TOWARDS THE NORTH-NORTHEAST...AND THUS ANY FLOODING CONCERNS WILL BE LARGELY CONFINED TO TRAINING STORMS. DAMAGING WINDS WILL REMAIN POSSIBLE OVERNIGHT...AND HAIL WILL ALSO BECOME A POSSIBILITY...ESPECIALLY ALONG/NORTH OF THE I-15 CORRIDOR WHERE 0-6KM SHEAR WILL EXCEED 30-35 KTS AND COOLER SUB-CLOUD LAYERS EXIST. ADDITIONALLY...SHOWERS WILL BE POSSIBLE ACROSS THE SIERRA AND PERHAPS THE LOWER ELEVATIONS OF INYO AND ESMERALDA COUNTIES ASSOCIATED WITH THE PRIMARY LOW CIRCULATION...HOWEVER WITH LIMITED MOISTURE IMPACTS SHOULD MAINLY BE WIND-RELATED IF ANYTHING. FRIDAY [12Z (5AM) THROUGH 06Z (11PM)]...THE APPROACHING UPPER LEVEL LOW WILL BRING STIFF SOUTHWESTERLY FLOW TO THE REGION FRIDAY. THIS WILL ACT TO TIGHTEN THE NORTH-SOUTH MOISTURE GRADIENT ACROSS THE FORECAST AREA. MODELS ARE IN BETTER AGREEMENT TODAY THAT THIS BOUNDARY WILL EXTEND ALONG THE WESTERN BORDERS OF LINCOLN AND CLARK COUNTIES SOUTH THROUGH EASTERN SAN BERNARDINO COUNTY BY 12Z (5AM) FRIDAY...THEN QUICKLY PUSH EAST TO NEAR THE COLORADO RIVER BY 18Z (11 AM) AND CENTRAL MOHAVE COUNTY BY 00Z (5PM). SHOWERS AND THUNDERSTORMS WILL BE A CONCERN MAINLY TO THE EAST OF THIS FEATURE...MEANING THAT CHANCES IN LAS VEGAS WILL END BEFORE NOON FRIDAY. STORM MOTION WILL INCREASE ONCE AGAIN TO 25-30 KTS TOWARDS THE NORTHEAST AND SHEAR VALUES WILL REMAIN ELEVATED. THUS ONCE AGAIN...THE PRIMARY CONCERN WILL BE DAMAGING WIND GUSTS AND POSSIBLY SOME HAIL. CHANCES FOR FLASH FLOODING WITH REMAIN POSSIBLE WITH TRAINING STORMS. BEHIND THIS BOUNDARY BREEZY TO LOCALLY WINDY CONDITIONS ARE EXPECTED. HOWEVER...THE LATEST HIGH-RES GUIDANCE HAS BACKED OFF A BIT ON THE MAGNITUDE. AT THIS TIME IT APPEARS THAT WINDS WILL REMAIN BELOW ADVISORY LEVELS AND BORDERLINE FOR RED FLAG CONDITIONS. INSTEAD OF REMOVING ANY HIGHLIGHTS THIS MORNING I`VE OPTED TO KEEP THE PRODUCTS IN PLACE AND LET THE DAY SHIFT TAKE ONE MORE LOOK AT THEM. .LONG TERM...SATURDAY THROUGH THURSDAY. NOT MUCH CHANGE FROM 24 HOURS AGO. A DRY SOUTHWEST FLOW WILL BE OVER THE ENTIRE FORECAST AREA SATURDAY THROUGH MONDAY. HIGH PRESSURE OVER TEXAS WILL EXPAND WEST TOWARD NEW MEXICO WHILE A TROUGH OF LOW PRESSURE STRETCHES GENERALLY NORTH-SOUTH ALONG THE WEST COAST STARTING LATE MONDAY. THIS COMBINATION WILL ALLOW SOUTHERLY FLOW TO DEVELOP WITH MOISTURE TRACKING NORTHWARD MAINLY INTO MOHAVE COUNTY. WILL CONTINUE THE SHOWER AND THUNDERSTORM CHANCES FOR THIS AREA TUESDAY. SOUTHERLY FLOW APPEARS TO STICK AROUND THROUGH THURSDAY, WITH MOISTURE SLIGHTLY EDGING WEST WEDNESDAY AND PERHAPS LINGERING INTO THURSDAY. THERE REMAINS UNCERTAINTY IN JUST HOW MUCH MOISTURE WILL ARRIVE AND HOW FAR WEST IT MAY TRACK. AS FOR TEMPERATURES, MONDAY APPEARS TO BE THE WARMEST DAY WITH TEMPS A DEGREE OR TWO ABOVE NORMAL. OTHERWISE NEAR TO SLIGHTLY BELOW NORMAL TEMPS ARE EXPECTED THROUGHOUT THE LONG-TERM PERIOD. BREEZY SOUTH TO SOUTHWEST WINDS WILL BE COMMON EACH AFTERNOON AND EARLY EVENING. && .AVIATION...FOR MCCARRAN...TYPICAL SOUTH-SOUTHWESTERLY WIND THROUGH MID MORNING BEFORE LIGHT EASTERLY WINDS DEVELOP BETWEEN 15Z AND 20Z. WINDS WILL RETURN TO A SOUTHWESTERLY DIRECTION AND INCREASE AFTER 20Z. GUSTS DURING THE AFTERNOON OF 15-25 KTS CAN BE EXPECTED. MAINLY SCT-BKN CLOUDS AOA 10K FEET THROUGH THE PERIOD. THERE IS THE SLIGHT CHANCE OF SHRA/TSRA AND TEMPORARILY LOWERED CIGS/VIS AND GUSTY WINDS TO IMPACT THE AIRPORT COMPLEX AS WELL AS THE APPROACH CORRIDORS BETWEEN ROUGHLY 00Z-18Z FRIDAY. STRONGER WINDS WITH GUSTS 25-30 KTS WILL BE POSSIBLE BY FRIDAY AFTERNOON. FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...BREEZY SOUTH TO SOUTHWEST WINDS ARE EXPECTED AGAIN TODAY WITH GUSTS GENERALLY 15-25 KTS DURING THE AFTERNOON. ISOLATED TO SCATTERED SHRA/TSRA POSSIBLE BEFORE 00Z...PRIMARILY SOUTH OF THE INTERSTATE 15 CORRIDOR. PRECIPITATION CHANCES WILL SPREAD NORTH INTO THE SOUTHERN GREAT BASIN THIS EVENING...THEN END RAPIDLY FROM WEST TO EAST THROUGH THE DAY FRIDAY. STORMS WILL HAVE THE POTENTIAL TO PRODUCE ERRATIC WIND GUSTS IN EXCESS OF 45 KTS. CIGS ARE GENERALLY EXPECTED TO REMAIN AOA 10K FEET EXCEPT NEAR SHRA/TSRA WHERE THEY COULD LOWER TO 6-8K FEET. && .SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. && $$ SHORT TERM/AVIATION...WOLCOTT LONG TERM.............PADDOCK FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE: HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1105 AM EDT THU AUG 6 2015 .SYNOPSIS... TEMPERATURES WILL RUN ABOVE NORMAL TODAY. THUNDERSTORMS WILL INCREASE IN COVERAGE THIS AFTERNOON AND EVENING AS MORE MOISTURE IS BROUGHT INTO THE REGION. AN AREA OF LOW PRESSURE AND ITS COLD FRONT WILL APPROACH FROM THE WEST AND MOVE ACROSS THE AREA LATE TONIGHT AND FRIDAY...BRINGING A CHANCE OF RAINFALL. A DRYING TREND IS EXPECTED INTO THE WEEKEND...AS HIGH PRESSURE CROSSES THE AREA SATURDAY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 11 AM THURSDAY...ISOLATED MORNING CONVECTION HAS ALL BUT DIMINISHED BUT AN INCREASE IN ACTIVITY IS EXPECTED THIS AFTERNOON. INCREASING SOUTHWEST FLOW AHEAD OF SLOW MOVING COLD FRONT WILL PUMP PLENTY OF GULF MOISTURE OVER THE REGION. DIURNAL HEATING WILL PUSH MLCAPE VALUES CLOSE TO 3000J/KG BY EARLY AFTERNOON. MID LEVEL CAPPING IS NOT AS STRONG AS IT WAS YESTERDAY SO EXPECT AN INCREASE IN COVERAGE FROM WEDNESDAY AFTERNOON. HOWEVER THERE IS MORE MOISTURE PRESENT...AT NEARLY ALL LEVELS...WHICH HAS LESSENED THE DOWNDRAFT CAPE SO WHILE COVERAGE OF STORMS MAY INCREASE THE AMOUNT OF STRONG TO SEVERE STORMS MAY BE SIMILAR TO YESTERDAY. HOWEVER WET MICROBURSTS WILL REMAIN A CONCERN. LOW LEVEL JET WILL BE PRESENT...SLOWLY GAINING STRENGTH THROUGH THE AFTERNOON AND EVENING HOURS...ADDING TO THE DAMAGING WIND POTENTIAL. CONVECTION WILL BE DELAYED UNTIL PEAK HEATING AS INITIALLY SURFACE HEATING AND CONVERGENCE ALONG THE SEA BREEZE/PIEDMONT TROUGH WILL BE THE ONLY SOURCE OF LIFT. LATER TODAY AND OVERNIGHT DYNAMICAL FORCING WILL START TO PLAY A LARGER ROLE IN MAINTAINING STORMS. HIGHS REMAIN ON TRACK FOR LOW TO MID 90S WITH HEAT INDEX VALUES STILL PROGGED TO END UP JUST SHORT OF HEAT ADVISORY CRITERIA. DISCUSSION FROM 630 AM THURSDAY FOLLOWS: LOOK FOR INCREASING CHANCES FOR CONVECTION THRUOUT THIS NEAR TERM PERIOD. THE MAIN CULPRIT AIDING THIS PCPN OUTBREAK COMES FROM A RATHER POTENT MID- LEVEL S/W TROF THAT MOVES FROM THE MID- MISSISSIPPI VALLEY EARLY THIS MORNING TO THE CAROLINAS BY DAYBREAK FRI. THIS SYSTEM WILL HAVE PLENTY OF MOISTURE TO WORK WITH EVENTHOUGH ITS MOVING WITHIN W TO NW FLOW ALOFT. MOISTURE ACCOMPANYING THIS S/W TROF AS WELL AS AN INFLUX IN THE LOWER LEVELS IE...FROM OFF THE ATLANTIC. LOOK FOR POPS IN THE MODEST TO GOOD CHANCE TODAY...POSSIBLY REACHING LIKELY LATE TODAY THRU TONIGHT. SEVERE TSTORM PARAMETERS POINT TOWARDS DAMAGING WIND GUSTS AS THE PRIMARY THREAT...WITH SPC INDICATING WET MICROBURSTS A POSSIBILITY. THE SPC OUTLINE FOR SVR WX ONLY CLIPS OUR WESTERN CWA BUT GIVEN THE DYNAMICS ACCOMPANYING THIS SYSTEM AND ITS INCREASING FORWARD PROGRESSION AFTER CROSSING THE APPALACHIANS...WILL GO AHEAD AND INDICATE A SEVERE THREAT FOR THE ENTIRE ILM CWA WITHIN THE HAZARDOUS WX OUTLOOK. TODAYS INSOLATION MAY AID ANY AFTN RENEGADE CONVECTION TO STRONG OR SEVERE LIMITS...WELL AHEAD OF THE APPROACHING MID-LEVEL S/W TROF. FOR MAX/MIN TEMPS...BASICALLY COMPROMISED AMONGST THE AVAILABLE MODEL MOS GUIDANCE...WITH LOW TO MID 90S FOR HIGHS...AND MID TO UPPER 70S...TO AROUND 80 AT THE COAST...FOR MINS. SFC DEWPOINTS ARE PROGGED AGAIN TO BE IN THE LOW TO MID 70S WITH A FEW UPPER 70S ALONG THE IMMEDIATE COAST. THIS WILL BRING HEAT INDEX VALUES JUST SHY OF HEAT ADVISORY THRESHOLDS OF GREATER THAN OR EQUAL TO 105 DEGREES. A FEW LOCATIONS MAY BRIEFLY TOUCH 105 THIS AFTN...WITH SFC DEWPOINTS THE DECIDING FACTOR RATHER THAN TEMPS. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY... ENERGY ALOFT CONTINUES TO STREAM ACROSS THE REGION ON FRIDAY WHILE THE COLD FRONT IS STILL SLOW TO MAKE PROGRESS THROUGH THE AREA...NOW TAKING UNTIL EVENING TO CLEAR. EXPECT AN ACTIVE DAY OF SHOWERS AND THUNDERSTORMS THOUGH THE CLOUD COVER TEMPERING OF AFTERNOON HEAT SHOULD MITIGATE SEVERE WEATHER THREAT. FRIDAY NIGHT INTO SATURDAY THE MID LEVELS WILL DRY OUT QUITE A BIT BUT UPPER LEVEL PVA REMAINS AS DOES SOME LOW LEVEL MOISTURE. MOST PLACES WILL STAY RAIN-FREE WITH JUST A FEW ISOLATED SHOWERS POSSIBLE. THE STEADIER COASTAL RAINFALL DEPICTED IN THE GFS APPEARS OVERDONE. TEMPERATURES WILL BE FAIRLY CLOSE TO SEASONABLE THROUGH THE PERIOD. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 3 AM THURSDAY... UPPER TROUGHINESS FLATTENS OUT SUNDAY AND MONDAY LEAVING VERY WEAK FLOW ALOFT LOCALLY. SIMILARLY THE FRONT OF THE SHORT TERM WILL HAVE WASHED OUT LEAVING BEHIND A POORLY DEFINED GRADIENT. MOISTURE ASSOCIATED WITH THE OLD FRONT MAY STILL LINGER JUST OFFSHORE BUT UNLESS THE SEA BREEZE MANAGES TO ADVECT ENOUGH OF IT ONSHORE MOST PLACES WILL STAY RAIN-FREE. THE EXCEPTION IS OVER INLAND ZONES MONDAY AFTERNOON WHEN SOME MID LEVEL PVA MAY GET UNDERWAY AHEAD OF THE MAIN TROUGH DEVELOPING OVER THE GREAT LAKES. THIS NEXT SYSTEM WILL EVENTUALLY TAKE ON AN IMPRESSIVE AMPLITUDE AND DRIVE A FRONT INT OUR AREA TUESDAY NIGHT OR WEDNESDAY. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... AS OF 12Z...SOME DENSE FOG AT FLO WILL HANG AROUND FOR AN HOUR OR SO...AND SHOULD MIX OUT BY 14Z. INCREASING CLOUDS LATER TODAY AS A FRONTAL SYSTEM APPROACHES FROM THE WEST. THE HRRR MODEL HAS INSTABILITY SHOWERS THIS AFTERNOON...LOOKS REASONABLE. THE MAIN PRECIP LOAD WILL COME TONIGHT AS THE DEEP MOISTURE INCREASES ALONG WITH DEEPENING LOW PRESSURE. CONVECTION SHOULD BREAK OUT OVERNIGHT WITH SOME HEAVY RAIN POSSIBLE. EXTENDED OUTLOOK...INCREASED CHANCES FOR CONVECTION THROUGH FRIDAY WITH THE APPROACH OF A COLD FRONT. HIGH PRESSURE WILL NOSE IN FROM THE NORTH SATURDAY AND SUNDAY. CHANCE FOR STORMS MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 11 AM THURSDAY...SOUTHWEST FLOW OF 10 TO 15 KT THIS MORNING WILL INCREASE TO 15 TO 20 KT THIS AFTERNOON AND EVENING AS GRADIENT TIGHTENS AHEAD OF AN APPROACHING COLD FRONT. SEAS CURRENTLY 2 TO 4 FT WILL BUILD TO 3 TO 5 FT THIS AFTERNOON AND EVENING. AT THIS POINT DO NOT PLAN TO RAISE SCEC HEADLINE BUT WILL CONTINUE TO MONITOR FOR POSSIBLE ISSUANCE WITH THE MIDDAY OR AFTERNOON UPDATES. DISCUSSION FROM 630 AM THURSDAY FOLLOWS: MODELS INDICATE A PINCHED SFC PRESSURE GRADIENT WILL DEVELOP THIS AFTERNOON AND PERSIST THROUGH TONIGHT. THIS A RESULT OF A RATHER POTENT MID-LEVEL S/W TROF OVER THE MID- MISSISSIPPI VALLEY THIS MORNING...THAT MOVES ESE...REACHING THE CAROLINAS OVERNIGHT. A DOUBLE BARREL SFC LOW WILL DEVELOP/EXIST ACROSS THE VA-NC BORDER BY LATE TONIGHT. LOOK FOR SSW-WSW WINDS TO INCREASE TO 15 TO 20 KT BY LATE THIS AFTN AND CONTINUING THRU TONIGHT. SIGNIFICANT SEAS WILL RESPOND TO THE INCREASING WINDS AND BUILD TO 3 TO 5 FT...POSSIBLY UP TO 6 FT OFF CAPE FEAR. MAY NEED A SCEC OR POSSIBLY A SHORT TERM SCA FOR LATE IN THIS PERIOD AND SUBSEQUENT ONES. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY... AUGUST ISN`T REALLY THE TIME OF YEAR FOR COLD FRONTAL PASSAGES BUT THIS SUMMER HAS LARGELY PROVEN EXCEPTION. A FAIRLY HEALTHY BOUNDARY WILL BE BEARING DOWN ON THE REGION ON FRIDAY SLATED FOR A FRIDAY NIGHT PASSAGE. IN THE COOLER SEASON FRONTS OFTEN RAMP WINDS AND/OR SEAS UP TO ADVISORY REALM BUT THIS IS OFTEN TOUGHER IN THE WARM SEASON AS THE FLOW ALOFT IS WEAKER. THIS SHOULD BE THE CASE WITH THIS SETUP AS BOTH REMAIN BELOW EVEN SCEC THRESHOLDS. VEERING FRIDAY NIGHT INTO SATURDAY WILL EVENTUALLY BRING ABOUT A NORTHERLY FLOW THAT WILL ABATE IN SPEED FAIRLY RAPIDLY. LONG TERM /SUNDAY THROUGH MONDAY/... AS OF 3 AM THURSDAY... AS THE FRONT FROM THE SHORT TERM WASHES OUT FAIRLY RAPIDLY TO OUR SOUTH OVER THE PERIOD THE LOCAL WINDS AND SEAS WILL BE MINIMAL. THE FLOW WILL VEER TO ONSHORE WHILE STAYING CAPPED AT 10 KNOTS ON SUNDAY AND THEN PERHAPS ANOTHER COMPASS POINT MONDAY. SEAS 2 OR PERHAPS 2 TO 3 FT AT MOST. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...III SHORT TERM...MBB LONG TERM...MBB AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
635 AM EDT THU AUG 6 2015 .SYNOPSIS... TEMPERATURES ARE EXPECTED TO REMAIN ABOVE NORMAL THROUGH THURSDAY. THUNDERSTORMS WILL INCREASE IN COVERAGE THURSDAY AS MORE MOISTURE IS BROUGHT INTO THE REGION. AN AREA OF LOW PRESSURE AND ITS COLD FRONT WILL APPROACH FROM THE WEST AND MOVE ACROSS THE AREA FRIDAY AND FRIDAY NIGHT...BRINGING A CHANCE OF RAINFALL. A DRYING TREND IS EXPECTED INTO THE WEEKEND...AS HIGH PRESSURE CROSSES THE AREA SATURDAY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM THURSDAY...LOOK FOR INCREASING CHANCES FOR CONVECTION THRUOUT THIS NEAR TERM PERIOD. THE MAIN CULPRIT AIDING THIS PCPN OUTBREAK COMES FROM A RATHER POTENT MID-LEVEL S/W TROF THAT MOVES FROM THE MID-MISSISSIPPI VALLEY EARLY THIS MORNING TO THE CAROLINAS BY DAYBREAK FRI. THIS SYSTEM WILL HAVE PLENTY OF MOISTURE TO WORK WITH EVENTHOUGH ITS MOVING WITHIN W TO NW FLOW ALOFT. MOISTURE ACCOMPANYING THIS S/W TROF AS WELL AS AN INFLUX IN THE LOWER LEVELS IE...FROM OFF THE ATLANTIC. LOOK FOR POPS IN THE MODEST TO GOOD CHANCE TODAY...POSSIBLY REACHING LIKELY LATE TODAY THRU TONIGHT. SEVERE TSTORM PARAMETERS POINT TOWARDS DAMAGING WIND GUSTS AS THE PRIMARY THREAT...WITH SPC INDICATING WET MICROBURSTS A POSSIBILITY. THE SPC OUTLINE FOR SVR WX ONLY CLIPS OUR WESTERN CWA BUT GIVEN THE DYNAMICS ACCOMPANYING THIS SYSTEM AND ITS INCREASING FORWARD PROGRESSION AFTER CROSSING THE APPALACHIANS...WILL GO AHEAD AND INDICATE A SEVERE THREAT FOR THE ENTIRE ILM CWA WITHIN THE HAZARDOUS WX OUTLOOK. TODAYS INSOLATION MAY AID ANY AFTN RENEGADE CONVECTION TO STRONG OR SEVERE LIMITS...WELL AHEAD OF THE APPROACHING MID-LEVEL S/W TROF. FOR MAX/MIN TEMPS...BASICALLY COMPROMISED AMONGST THE AVAILABLE MODEL MOS GUIDANCE...WITH LOW TO MID 90S FOR HIGHS...AND MID TO UPPER 70S...TO AROUND 80 AT THE COAST...FOR MINS. SFC DEWPOINTS ARE PROGGED AGAIN TO BE IN THE LOW TO MID 70S WITH A FEW UPPER 70S ALONG THE IMMEDIATE COAST. THIS WILL BRING HEAT INDEX VALUES JUST SHY OF HEAT ADVISORY THRESHOLDS OF GREATER THAN OR EQUAL TO 105 DEGREES. A FEW LOCATIONS MAY BRIEFLY TOUCH 105 THIS AFTN...WITH SFC DEWPOINTS THE DECIDING FACTOR RATHER THAN TEMPS. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY... ENERGY ALOFT CONTINUES TO STREAM ACROSS THE REGION ON FRIDAY WHILE THE COLD FRONT IS STILL SLOW TO MAKE PROGRESS THROUGH THE AREA...NOW TAKING UNTIL EVENING TO CLEAR. EXPECT AN ACTIVE DAY OF SHOWERS AND THUNDERSTORMS THOUGH THE CLOUD COVER TEMPERING OF AFTERNOON HEAT SHOULD MITIGATE SEVERE WEATHER THREAT. FRIDAY NIGHT INTO SATURDAY THE MID LEVELS WILL DRY OUT QUITE A BIT BUT UPPER LEVEL PVA REMAINS AS DOES SOME LOW LEVEL MOISTURE. MOST PLACES WILL STAY RAIN-FREE WITH JUST A FEW ISOLATED SHOWERS POSSIBLE. THE STEADIER COASTAL RAINFALL DEPICTED IN THE GFS APPEARS OVERDONE. TEMPERATURES WILL BE FAIRLY CLOSE TO SEASONABLE THROUGH THE PERIOD. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 3 AM THURSDAY... UPPER TROUGHINESS FLATTENS OUT SUNDAY AND MONDAY LEAVING VERY WEAK FLOW ALOFT LOCALLY. SIMILARLY THE FRONT OF THE SHORT TERM WILL HAVE WASHED OUT LEAVING BEHIND A POORLY DEFINED GRADIENT. MOISTURE ASSOCIATED WITH THE OLD FRONT MAY STILL LINGER JUST OFFSHORE BUT UNLESS THE SEA BREEZE MANAGES TO ADVECT ENOUGH OF IT ONSHORE MOST PLACES WILL STAY RAIN-FREE. THE EXCEPTION IS OVER INLAND ZONES MONDAY AFTERNOON WHEN SOME MID LEVEL PVA MAY GET UNDERWAY AHEAD OF THE MAIN TROUGH DEVELOPING OVER THE GREAT LAKES. THIS NEXT SYSTEM WILL EVENTUALLY TAKE ON AN IMPRESSIVE AMPLITUDE AND DRIVE A FRONT INT OUR AREA TUESDAY NIGHT OR WEDNESDAY. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 12Z...SOME DENSE FOG AT FLO WILL HANG AROUND FOR AN HOUR OR SO...AND SHOULD MIX OUT BY 14Z. INCREASING CLOUDS LATER TODAY AS A FRONTAL SYSTEM APPROACHES FROM THE WEST. THE HRRR MODEL HAS INSTABILITY SHOWERS THIS AFTERNOON...LOOKS REASONABLE. THE MAIN PRECIP LOAD WILL COME TONIGHT AS THE DEEP MOISTURE INCREASES ALONG WITH DEEPENING LOW PRESSURE. CONVECTION SHOULD BREAK OUT OVERNIGHT WITH SOME HEAVY RAIN POSSIBLE. EXTENDED OUTLOOK...INCREASED CHANCES FOR CONVECTION THROUGH FRIDAY WITH THE APPROACH OF A COLD FRONT. HIGH PRESSURE WILL NOSE IN FROM THE NORTH SATURDAY AND SUNDAY. CHANCE FOR STORMS MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM THURSDAY...MODELS INDICATE A PINCHED SFC PRESSURE GRADIENT WILL DEVELOP THIS AFTERNOON AND PERSIST THROUGH TONIGHT. THIS A RESULT OF A RATHER POTENT MID-LEVEL S/W TROF OVER THE MID- MISSISSIPPI VALLEY THIS MORNING...THAT MOVES ESE...REACHING THE CAROLINAS OVERNIGHT. A DOUBLE BARREL SFC LOW WILL DEVELOP/EXIST ACROSS THE VA-NC BORDER BY LATE TONIGHT. LOOK FOR SSW-WSW WINDS TO INCREASE TO 15 TO 20 KT BY LATE THIS AFTN AND CONTINUING THRU TONIGHT. SIGNIFICANT SEAS WILL RESPOND TO THE INCREASING WINDS AND BUILD TO 3 TO 5 FT...POSSIBLY UP TO 6 FT OFF CAPE FEAR. MAY NEED A SCEC OR POSSIBLY A SHORT TERM SCA FOR LATE IN THIS PERIOD AND SUBSEQUENT ONES. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY... AUGUST ISN`T REALLY THE TIME OF YEAR FOR COLD FRONTAL PASSAGES BUT THIS SUMMER HAS LARGELY PROVEN EXCEPTION. A FAIRLY HEALTHY BOUNDARY WILL BE BEARING DOWN ON THE REGION ON FRIDAY SLATED FOR A FRIDAY NIGHT PASSAGE. IN THE COOLER SEASON FRONTS OFTEN RAMP WINDS AND/OR SEAS UP TO ADVISORY REALM BUT THIS IS OFTEN TOUGHER IN THE WARM SEASON AS THE FLOW ALOFT IS WEAKER. THIS SHOULD BE THE CASE WITH THIS SETUP AS BOTH REMAIN BELOW EVEN SCEC THRESHOLDS. VEERING FRIDAY NIGHT INTO SATURDAY WILL EVENTUALLY BRING ABOUT A NORTHERLY FLOW THAT WILL ABATE IN SPEED FAIRLY RAPIDLY. LONG TERM /SUNDAY THROUGH MONDAY/... AS OF 3 AM THURSDAY... AS THE FRONT FROM THE SHORT TERM WASHES OUT FAIRLY RAPIDLY TO OUR SOUTH OVER THE PERIOD THE LOCAL WINDS AND SEAS WILL BE MINIMAL. THE FLOW WILL VEER TO ONSHORE WHILE STAYING CAPPED AT 10 KNOTS ON SUNDAY AND THEN PERHAPS ANOTHER COMPASS POINT MONDAY. SEAS 2 OR PERHAPS 2 TO 3 FT AT MOST. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...MBB NEAR TERM...DCH SHORT TERM...MBB LONG TERM...MBB AVIATION...DCH/SGL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
623 AM EDT THU AUG 6 2015 .SYNOPSIS... TEMPERATURES ARE EXPECTED TO REMAIN ABOVE NORMAL THROUGH THURSDAY. THUNDERSTORMS WILL INCREASE IN COVERAGE THURSDAY AS MORE MOISTURE IS BROUGHT INTO THE REGION. AN AREA OF LOW PRESSURE AND ITS COLD FRONT WILL APPROACH FROM THE WEST AND MOVE ACROSS THE AREA FRIDAY AND FRIDAY NIGHT...BRINGING A CHANCE OF RAINFALL. A DRYING TREND IS EXPECTED INTO THE WEEKEND...AS HIGH PRESSURE CROSSES THE AREA SATURDAY THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 345 AM THURSDAY...LOOK FOR INCREASING CHANCES FOR CONVECTION THRUOUT THIS NEAR TERM PERIOD. THE MAIN CULPRIT AIDING THIS PCPN OUTBREAK COMES FROM A RATHER POTENT MID-LEVEL S/W TROF THAT MOVES FROM THE MID-MISSISSIPPI VALLEY THIS MORNING TO THE CAROLINAS DURING THE PRE-DAWN FRI HOURS. THIS SYSTEM WILL HAVE PLENTY OF MOISTURE TO WORK WITH EVENTHOUGH ITS MOVING WITHIN W TO NW FLOW ALOFT. MOISTURE ACCOMPANYING THIS S/W TROF AS WELL AS AN INFLUX IN THE LOWER LEVELS IE...FROM OFF THE ATLANTIC. LOOK FOR POPS IN THE MODEST TO GOOD CHANCE TODAY...POSSIBLY REACHING LIKELY LATE TODAY THRU TONIGHT. SEVERE TSTORM PARAMETERS POINT TOWARDS DAMAGING WIND GUSTS AS THE PRIMARY THREAT...WITH SPC INDICATING WET MICROBURSTS A POSSIBILITY. THE SPC OUTLINE FOR SVR WX ONLY CLIPS OUR WESTERN CWA BUT GIVEN THE DYNAMICS ACCOMPANYING THIS SYSTEM AND ITS INCREASING FORWARD PROGRESSION AFTER CROSSING THE APPALACHIANS...WILL GO AHEAD AND INDICATE A SEVERE THREAT FOR THE ENTIRE ILM CWA WITHIN THE HAZARDOUS WX OUTLOOK AND INCLUDE THE TONIGHT PERIOD. TODAYS INSOLATION MAY AID ANY AFTN RENEGADE CONVECTION TO STRONG OR SEVERE LIMITS...WELL AHEAD OF THE APPROACHING MID-LEVEL S/W TROF. FOR MAX/MIN TEMPS...BASICALLY COMPROMISED AMONGST THE AVAILABLE MODEL MOS GUIDANCE...WITH LOW TO MID 90S FOR HIGHS...AND MID TO UPPER 70S...TO AROUND 80 AT THE COAST...FOR MINS. SFC DEWPOINTS ARE PROGGED AGAIN TO BE IN THE LOW TO MID 70S WITH A FEW UPPER 70S ALONG THE IMMEDIATE COAST. THIS WILL BRING HEAT INDEX VALUES JUST SHY OF HEAT ADVISORY THRESHOLDS OF GREATER THAN OR EQUAL TO 105 DEGREES. A FEW LOCATIONS MAY BRIEFLY TOUCH 105 THIS AFTN...WITH SFC DEWPOINTS THE DECIDING FACTOR RATHER THAN TEMPS. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY... ENERGY ALOFT CONTINUES TO STREAM ACROSS THE REGION ON FRIDAY WHILE THE COLD FRONT IS STILL SLOW TO MAKE PROGRESS THROUGH THE AREA...NOW TAKING UNTIL EVENING TO CLEAR. EXPECT AN ACTIVE DAY OF SHOWERS AND THUNDERSTORMS THOUGH THE CLOUD COVER TEMPERING OF AFTERNOON HEAT SHOULD MITIGATE SEVERE WEATHER THREAT. FRIDAY NIGHT INTO SATURDAY THE MID LEVELS WILL DRY OUT QUITE A BIT BUT UPPER LEVEL PVA REMAINS AS DOES SOME LOW LEVEL MOISTURE. MOST PLACES WILL STAY RAIN-FREE WITH JUST A FEW ISOLATED SHOWERS POSSIBLE. THE STEADIER COASTAL RAINFALL DEPICTED IN THE GFS APPEARS OVERDONE. TEMPERATURES WILL BE FAIRLY CLOSE TO SEASONABLE THROUGH THE PERIOD. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 3 AM THURSDAY... UPPER TROUGHINESS FLATTENS OUT SUNDAY AND MONDAY LEAVING VERY WEAK FLOW ALOFT LOCALLY. SIMILARLY THE FRONT OF THE SHORT TERM WILL HAVE WASHED OUT LEAVING BEHIND A POORLY DEFINED GRADIENT. MOISTURE ASSOCIATED WITH THE OLD FRONT MAY STILL LINGER JUST OFFSHORE BUT UNLESS THE SEA BREEZE MANAGES TO ADVECT ENOUGH OF IT ONSHORE MOST PLACES WILL STAY RAIN-FREE. THE EXCEPTION IS OVER INLAND ZONES MONDAY AFTERNOON WHEN SOME MID LEVEL PVA MAY GET UNDERWAY AHEAD OF THE MAIN TROUGH DEVELOPING OVER THE GREAT LAKES. THIS NEXT SYSTEM WILL EVENTUALLY TAKE ON AN IMPRESSIVE AMPLITUDE AND DRIVE A FRONT INT OUR AREA TUESDAY NIGHT OR WEDNESDAY. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 12Z...SOME DENSE FOG AT FLO WILL HANG AROUND FOR AN HOUR OR SO...AND SHOULD MIX OUT BY 14Z. INCREASING CLOUDS LATER TODAY AS A FRONTAL SYSTEM APPROACHES FROM THE WEST. THE HRRR MODEL HAS INSTABILITY SHOWERS THIS AFTERNOON...LOOKS REASONABLE. THE MAIN PRECIP LOAD WILL COME TONIGHT AS THE DEEP MOISTURE INCREASES ALONG WITH DEEPENING LOW PRESSURE. CONVECTION SHOULD BREAK OUT OVERNIGHT WITH SOME HEAVY RAIN POSSIBLE. EXTENDED OUTLOOK...INCREASED CHANCES FOR CONVECTION THROUGH FRIDAY WITH THE APPROACH OF A COLD FRONT. HIGH PRESSURE WILL NOSE IN FROM THE NORTH SATURDAY AND SUNDAY. CHANCE FOR STORMS MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 345 AM THURSDAY...MODELS INDICATE A PINCHED SFC PRESSURE GRADIENT WILL DEVELOP THIS AFTERNOON AND PERSIST THROUGH TONIGHT. THIS A RESULT OF A RATHER POTENT MID-LEVEL S/W TROF OVER THE MID- MISSISSIPPI VALLEY THIS MORNING MOVING ESE...AND REACHING THE CAROLINAS OVERNIGHT. A DOUBLE BARREL LOW WILL DEVELOP/EXIST ACROSS THE VA-NC BORDER BY LATE TONIGHT. LOOK FOR SSW-WSW WINDS TO INCREASE TO 15 TO 20 KT WITH GUSTS UP TO 25 KT BY LATE THIS AFTN AND CONTINUING THRU TONIGHT. SIGNIFICANT SEAS WILL RESPOND TO THE INCREASING WINDS AND BUILD TO 3 TO 5 FT...POSSIBLY UP TO 6 FT OFF CAPE FEAR. WILL LIKELY POST A SCEC OR POSSIBLY A SHORT TERM SCA AT THE NEXT UPDATE IF THE 06Z MODEL RUNS CONTINUE THIS TREND. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY... AUGUST ISN`T REALLY THE TIME OF YEAR FOR COLD FRONTAL PASSAGES BUT THIS SUMMER HAS LARGELY PROVEN EXCEPTION. A FAIRLY HEALTHY BOUNDARY WILL BE BEARING DOWN ON THE REGION ON FRIDAY SLATED FOR A FRIDAY NIGHT PASSAGE. IN THE COOLER SEASON FRONTS OFTEN RAMP WINDS AND/OR SEAS UP TO ADVISORY REALM BUT THIS IS OFTEN TOUGHER IN THE WARM SEASON AS THE FLOW ALOFT IS WEAKER. THIS SHOULD BE THE CASE WITH THIS SETUP AS BOTH REMAIN BELOW EVEN SCEC THRESHOLDS. VEERING FRIDAY NIGHT INTO SATURDAY WILL EVENTUALLY BRING ABOUT A NORTHERLY FLOW THAT WILL ABATE IN SPEED FAIRLY RAPIDLY. LONG TERM /SUNDAY THROUGH MONDAY/... AS OF 3 AM THURSDAY... AS THE FRONT FROM THE SHORT TERM WASHES OUT FAIRLY RAPIDLY TO OUR SOUTH OVER THE PERIOD THE LOCAL WINDS AND SEAS WILL BE MINIMAL. THE FLOW WILL VEER TO ONSHORE WHILE STAYING CAPPED AT 10 KNOTS ON SUNDAY AND THEN PERHAPS ANOTHER COMPASS POINT MONDAY. SEAS 2 OR PERHAPS 2 TO 3 FT AT MOST. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...MBB NEAR TERM...DCH SHORT TERM...MBB LONG TERM...MBB AVIATION...43 MARINE...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
735 AM EDT THU AUG 6 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK TO THE SOUTH OF PENNSYLVANIA THROUGH THE END OF THE WEEK AND MOVE OFFSHORE THIS WEEKEND. HIGH PRESSURE WILL MOVE INTO THE AREA BEHIND THE DEPARTING LOW. RAIN IS LIKELY NEAR THE MASON DIXON LINE THIS AFTERNOON INTO TONIGHT BEFORE CONDITIONS DRY OUT FOR THE MOST PART ON FRIDAY. && .NEAR TERM /UNTIL NOON TODAY/... COOL NORTHERN TIER VALLEYS ARE SOCKED IN WITH THICK FOG EARLY THIS MORNING. EXPECT THIS TO DISSIPATE SHORTLY PAST 12Z. MID TO HIGH CLOUDS WILL BE INCREASING FROM SW TO NE THROUGH MID DAY IN ADVANCE OF WELL DEFINED MID/UPPER LEVEL SYSTEM /FOR THIS TIME OF YEAR/ AND DEVELOPING SFC LOW OVER THE MID MS/LOWER OH VALLEY. SFC HIGH EXTENDING SEWD FROM THE UPPER GREAT LAKES AND LOW PW AIR WILL KEEP DRY WX INTACT THIS MORNING. && .SHORT TERM /NOON TODAY THROUGH 6 AM FRIDAY/... SHORT TERM MODELS ARE IN GOOD AGREEMENT IN TAKING THE H5 HEIGHT FALL CENTER AND SFC REFLECTION TO THE SOUTH OF CENTRAL PA THROUGH THE PERIOD...FROM KY EWD ACROSS THE CENTRAL APPALACHIANS AND INTO THE SRN MID ATLC. HOWEVER...THERE CONTINUES TO BE SOME UNCERTAINTY WITH RESPECT TO THE QPF DISTRIBUTIONS/WARM SEASON OVERRUNNING SCENARIO TO THE NORTH OF THE SFC WAVE. FOR THIS REASON STAYED PRETTY CLOSE TO A BLENDED SOLUTION WITH WPC QPF...WHICH LEANED TOWARD THE HI RES MODELS. THE FINAL NDFD FCST WILL SHOW AN INCREASE IN POPS OVER THE FAR SRN TIER ZONES FROM THE PA TURNPIKE SWD TO THE MASON DIXON LINE. THE LATEST HRRR AND 00Z SSEO ARE STRADDLING THE PA/MD LINE WITH SHOWER ACTIVITY THRU 18-21Z TIME FRAME. THERE SHOULD BE A FAIRLY SHARP GRADIENT TO THE NRN EDGE OF THE RAIN AND MODELS MAY BE TOO BULLISH ON WAA/OVERRUNNING COMPONENT IN LIEU OF CONVECTION FARTHER TO THE SOUTH. LATER SHIFTS MAY NEED TO MAKE N-S ADJUSTMENTS IN P0PS/QPF AS THE PCPN PATTERN EVOLVES THROUGH EARLY TONIGHT. POPS WILL TREND LOWER FROM NW TO SE INTO EARLY FRIDAY WITH M/CLR SKIES/PATCHY FOG OVER THE NW MTNS BY FRIDAY MORNING. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... A FEW LINGERING SHRA MAY AFFECT THE SE COUNTIES INTO PART OF FRIDAY...AS SFC LOW PUSHES OFF THE COAST NR THE SOUTHERN DELMARVA. MDL SOUNDINGS IMPLY PERSISTENT CLOUDINESS THRU MUCH OF FRIDAY ACROSS THE SOUTHERN COUNTIES...WHERE MOIST EASTERLY FLOW WILL LINGER. ACROSS NORTHERN PA...A MUCH BRIGHTER DAY EXPECTED. GEFS MEAN 925/850 TEMPS SUPPORT MAX TEMPS BTWN 75-80F. GENERALLY FAIR AND SEASONABLE WX EXPECTED THIS WEEKEND...AS CENTRAL PA WILL BE IN REGION OF LG SCALE SUBSIDENCE ON EAST SIDE OF UPPER RIDGE OVR THE MISS VALLEY. WILL PAINT A SLIGHT CHC OF PM SHRA/TSRA SUNDAY TO ACCOUNT FOR PASSAGE OF WEAK SHORTWAVE RIDING N PERIPHERY OF MISS VALLEY UPPER RIDGE. GEFS PLUMES INDICATE A GRADUAL WARMING TREND INTO THE WEEKEND...WITH READINGS CLOSE TO AVERAGE FOR EARLY AUGUST. SOME TIMING DIFFS HAVE ARISEN WITH ANTICIPATED COLD FRONT EARLY NEXT WEEK. HAVE SIDED WITH THE GEFS/ECENS AND OPER CANADIAN...ALL OF WHICH INDICATE A FROPA LATE MONDAY/EARLY TUE...AS OPPOSED TO THE OPER ECMWF...WHICH IS 12-24HRS SLOWER AND IMPLIES A DRY MONDAY. HAVE INCREASED CHC OF SHRA/TSRA MON PM...AS HGTS FALL AHEAD OF APPROACHING TROF AND A SURGE OF HIGHER PWATS WORK INTO THE REGION ON SW FLOW. DEEPENING TROUGH AND SLOWING COLD FRONT WILL LKLY RESULT IN LINGERING SHRA/TSRA INTO TUESDAY. GEFS AND EC BOTH CURRENTLY INDICATE THE POSSIBILITY OF HVY RAINFALL ACROSS EASTERN PA ASSOC WITH THIS SLOWING FRONT. COOLER/DRIER WX IS LIKELY BY MIDWEEK. HOWEVER...UPPER TROF/COOL MID LVL TEMPS OVR THE REGION COULD PROMOTE PM SHOWERS...ESP OVR THE MTNS. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... BRIEF VLIFR FOG/ST AT BFD HAS DISSIPATED. LOOK FOR VFR TO PREVAIL TODAY WITH LGT/VRB WINDS AND EXPANSIVE SHIELD OF LYRD MID AND HIGH CLOUDS OVERSPREADING THE AIRSPACE FROM SW TO NE THRU THE AFTERNOON. LOW PRESSURE WILL TRACK EWD FROM THE MID MS/LOWER OH VALLEYS INTO THE SRN MID ATLC STATES ON FRIDAY AND OFF THE EAST COAST ON SAT. HIGH PRESSURE/VFR WILL MOVE INTO THE AIRSPACE BEHIND THE DEPARTING SFC LOW. THE GREATEST RISK FOR RAIN/SUB-VFR CIGS WILL BE ACROSS THE SRN 1/3 OF THE AIRSPACE TONIGHT INTO EARLY FRIDAY. CONFIDENCE IS LOW AND THEREFORE KEPT CIGS AOA 050. OUTLOOK... SAT-SUN...PATCHY A.M. FOG/VFR. MON...VFR WITH CHC OF TSTMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...DEVOIR/FITZGERALD/STEINBUGL SHORT TERM...STEINBUGL LONG TERM...FITZGERALD AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
721 AM EDT THU AUG 6 2015 .SYNOPSIS... LOW PRESSURE WILL TRACK TO THE SOUTH OF PENNSYLVANIA THROUGH THE END OF THE WEEK AND MOVE OFFSHORE THIS WEEKEND. HIGH PRESSURE WILL MOVE INTO THE AREA BEHIND THE DEPARTING LOW. RAIN IS LIKELY NEAR THE MASON DIXON LINE THIS AFTERNOON INTO TONIGHT BEFORE CONDITIONS DRY OUT FOR THE MOST PART ON FRIDAY. && .NEAR TERM /UNTIL NOON TODAY/... COOL NORTHERN TIER VALLEYS ARE SOCKED IN WITH THICK FOG EARLY THIS MORNING. EXPECT THIS TO DISSIPATE SHORTLY PAST 12Z. MID TO HIGH CLOUDS WILL BE INCREASING FROM SW TO NE THROUGH MID DAY IN ADVANCE OF WELL DEFINED MID/UPPER LEVEL SYSTEM /FOR THIS TIME OF YEAR/ AND DEVELOPING SFC LOW OVER THE MID MS/LOWER OH VALLEY. SFC HIGH EXTENDING SEWD FROM THE UPPER GREAT LAKES AND LOW PW AIR WILL KEEP DRY WX INTACT THIS MORNING. && .SHORT TERM /NOON TODAY THROUGH 6 AM FRIDAY/... SHORT TERM MODELS ARE IN GOOD AGREEMENT IN TAKING THE H5 HEIGHT FALL CENTER AND SFC REFLECTION TO THE SOUTH OF CENTRAL PA THROUGH THE PERIOD...FROM KY EWD ACROSS THE CENTRAL APPALACHIANS AND INTO THE SRN MID ATLC. HOWEVER...THERE CONTINUES TO BE SOME UNCERTAINTY WITH RESPECT TO THE QPF DISTRIBUTIONS/WARM SEASON OVERRUNNING SCENARIO TO THE NORTH OF THE SFC WAVE. FOR THIS REASON STAYED PRETTY CLOSE TO A BLENDED SOLUTION WITH WPC QPF...WHICH LEANED TOWARD THE HI RES MODELS. THE FINAL NDFD FCST WILL SHOW AN INCREASE IN POPS OVER THE FAR SRN TIER ZONES FROM THE PA TURNPIKE SWD TO THE MASON DIXON LINE. THE LATEST HRRR AND 00Z SSEO ARE STRADDLING THE PA/MD LINE WITH SHOWER ACTIVITY THRU 18-21Z TIME FRAME. THERE SHOULD BE A FAIRLY SHARP GRADIENT TO THE NRN EDGE OF THE RAIN AND MODELS MAY BE TOO BULLISH ON WAA/OVERRUNNING COMPONENT IN LIEU OF CONVECTION FARTHER TO THE SOUTH. LATER SHIFTS MAY NEED TO MAKE N-S ADJUSTMENTS IN P0PS/QPF AS THE PCPN PATTERN EVOLVES THROUGH EARLY TONIGHT. POPS WILL TREND LOWER FROM NW TO SE INTO EARLY FRIDAY WITH M/CLR SKIES/PATCHY FOG OVER THE NW MTNS BY FRIDAY MORNING. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... A FEW LINGERING SHRA MAY AFFECT THE SE COUNTIES INTO PART OF FRIDAY...AS SFC LOW PUSHES OFF THE COAST NR THE SOUTHERN DELMARVA. MDL SOUNDINGS IMPLY PERSISTENT CLOUDINESS THRU MUCH OF FRIDAY ACROSS THE SOUTHERN COUNTIES...WHERE MOIST EASTERLY FLOW WILL LINGER. ACROSS NORTHERN PA...A MUCH BRIGHTER DAY EXPECTED. GEFS MEAN 925/850 TEMPS SUPPORT MAX TEMPS BTWN 75-80F. GENERALLY FAIR AND SEASONABLE WX EXPECTED THIS WEEKEND...AS CENTRAL PA WILL BE IN REGION OF LG SCALE SUBSIDENCE ON EAST SIDE OF UPPER RIDGE OVR THE MISS VALLEY. WILL PAINT A SLIGHT CHC OF PM SHRA/TSRA SUNDAY TO ACCOUNT FOR PASSAGE OF WEAK SHORTWAVE RIDING N PERIPHERY OF MISS VALLEY UPPER RIDGE. GEFS PLUMES INDICATE A GRADUAL WARMING TREND INTO THE WEEKEND...WITH READINGS CLOSE TO AVERAGE FOR EARLY AUGUST. SOME TIMING DIFFS HAVE ARISEN WITH ANTICIPATED COLD FRONT EARLY NEXT WEEK. HAVE SIDED WITH THE GEFS/ECENS AND OPER CANADIAN...ALL OF WHICH INDICATE A FROPA LATE MONDAY/EARLY TUE...AS OPPOSED TO THE OPER ECMWF...WHICH IS 12-24HRS SLOWER AND IMPLIES A DRY MONDAY. HAVE INCREASED CHC OF SHRA/TSRA MON PM...AS HGTS FALL AHEAD OF APPROACHING TROF AND A SURGE OF HIGHER PWATS WORK INTO THE REGION ON SW FLOW. DEEPENING TROUGH AND SLOWING COLD FRONT WILL LKLY RESULT IN LINGERING SHRA/TSRA INTO TUESDAY. GEFS AND EC BOTH CURRENTLY INDICATE THE POSSIBILITY OF HVY RAINFALL ACROSS EASTERN PA ASSOC WITH THIS SLOWING FRONT. COOLER/DRIER WX IS LIKELY BY MIDWEEK. HOWEVER...UPPER TROF/COOL MID LVL TEMPS OVR THE REGION COULD PROMOTE PM SHOWERS...ESP OVR THE MTNS. && .AVIATION /11Z THURSDAY THROUGH MONDAY/... M/CLR SKIES WITH HIGH CI INCR FROM W TO E. IFR FOG PSBL AT BFD BUT CONFIDENCE IN SUSTAINED IFR IS LOW THEREFORE CUT BACK TO TEMPO 3SM BR SCT001. LOW PRESSURE WILL TRACK EWD FROM THE MID MS/LOWER OH VALLEYS INTO THE SRN MID ATLC STATES ON FRIDAY AND OFF THE EAST COAST ON SAT. HIGH PRESSURE/VFR WILL MOVE INTO THE AIRSPACE BEHIND THE DEPARTING SFC LOW. THE GREATEST RISK FOR RAIN/SUB-VFR CIGS WILL BE ACROSS THE SRN 1/3 OF THE AIRSPACE TONIGHT INTO EARLY FRIDAY. CONFIDENCE IS LOW AND THEREFORE KEPT CIGS AOA 050. OUTLOOK... SAT-SUN...PATCHY A.M. FOG/VFR. MON...VFR WITH CHC OF TSTMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...DEVOIR/FITZGERALD SHORT TERM...STEINBUGL LONG TERM...FITZGERALD AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
939 AM CDT THU AUG 6 2015 .UPDATE... FOR MORNING UPDATE. && .DISCUSSION... MORNING UPDATE INCLUDES BACKING OFF POPS JUST A LITTLE BASED ON CURRENT RADAR TRENDS...ESPECIALLY ACROSS THE WEST. ALSO...REDUCED THE COVERAGE OF THUNDER. LATEST GUIDANCE SUGGESTS THE POTENTIAL CONTINUES FOR ADDITIONAL DEVELOPMENT EAST OF I-65 THIS AFTERNOON. NOT TOO CRAZY ABOUT THIS BUT WILL KEEP SOME POPS IN THROUGH THE LATE AFTERNOON BEFORE BACKING OFF OVERNIGHT. CLOUD COVER WILL LIKELY HAMPER HIGHS TODAY. MIGHT BE A LITTLE WARM WITH CURRENT FORECAST BUT WILL MONITOR AND UPDATE IF NEEDED. UPDATES ALREADY OUT. UNGER && .AVIATION... 12Z TAF DISCUSSION. LEANED HEAVILY ON HRRR MODEL FOR TIMING OF IMPACTS. -SHRA/-TSRA TO CONTINUE SPREADING ACROSS AREA AIRPORTS THROUGH 16Z AT CKV/BNA AND 22Z AT CSV. VCSH AFTER THAT TIME AT AIRPORTS WITH MVFR/IFR CIGS/VIS DEVELOPING THURSDAY EVENING/NIGHT. SHAMBURGER && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
652 AM CDT THU AUG 6 2015 .UPDATE... 12Z TAF DISCUSSION. && .AVIATION UPDATE... LEANED HEAVILY ON HRRR MODEL FOR TIMING OF IMPACTS. -SHRA/-TSRA TO CONTINUE SPREADING ACROSS AREA AIRPORTS THROUGH 16Z AT CKV/BNA AND 22Z AT CSV. VCSH AFTER THAT TIME AT AIRPORTS WITH MVFR/IFR CIGS/VIS DEVELOPING THURSDAY EVENING/NIGHT. SHAMBURGER && .PREV DISCUSSION... /ISSUED 346 AM CDT THU AUG 6 2015/ DISCUSSION... SHOWERS AND THUNDERSTORMS CONTINUE TO MOVE ACROSS THE FORECAST AREA THIS EARLY MORNING WITH THE HEAVIEST RAIN CONCENTRATED OVER SOUTHERN MIDDLE TENNESSEE AS WELL AS NORTHEAST MISSISSIPPI AND NORTHWEST ALABAMA. FOR TODAY...IT WILL BE A SOMEWHAT COMPLEX FORECAST SITUATION AS THE ONGOING STORMS ARE A FEW HOURS EARLY IN ARRIVAL AND WILL IMPACT WHAT HAPPENS LATER TODAY. SHORT RANGE MODELS ARE HINTING AT REDEVELOPMENT THIS AFTERNOON ESPECIALLY NEAR AND EAST OF INTERSTATE 65. IF STORMS CAN GET GOING THIS AFTERNOON...THESE WOULD HAVE THE POTENTIAL TO BE STRONG TO MAYBE EVEN SEVERE WITH WIND GUSTS BEING THE MAIN THREATS. REGARDLESS OF WHETHER STORMS REDEVELOP OR NOT...CLOUD COVER AND LIGHT SHOWERS WILL GENERALLY REMAIN OVER THE AREA FOR MUCH OF THE DAY IMPACTING HIGH TEMPERATURES. AS LONG AS THE AREA DOES NOT BREAK OUT INTO FULL ON SUNSHINE TODAY...LOW TO MID 80S SEEM REASONABLE WITH ALL MOS GUIDANCE AGREEING WITH THIS SOLUTION TOO. ONE CONCERN IS ACROSS NORTHWEST MIDDLE TENNESSEE WHERE CONFIDENCE IS NOT QUITE AS HIGH THAT CONVECTION WILL REMAIN OVER THIS AREA ALL DAY...SO SOMETHING TO DEFINITELY WATCH WITH THE MORNING UPDATE. RAIN WILL QUICKLY END FROM WEST TO EAST THIS EVENING WITH MOST OF THE RAIN OUT OF THE AREA BY MIDNIGHT. MOSTLY DRY CONDITIONS CAN BE EXPECTED ON FRIDAY ALTHOUGH SOME RESIDUAL CLOUD COVER WILL REMAIN KEEPING A LID ON TEMPERATURES FROM REACHING THE 90 DEGREE MARK WITH LOCATIONS REMAINING IN THE MID TO UPPER 80S. BY THE WEEKEND...RAIN CHANCES NOW LOOK MINIMAL AT BEST WITH THE UPPER RIDGE SITUATED OVER TEXAS BUILDING OVER THE AREA. IN FACT...THIS WILL SPELL A NOTICEABLE INCREASE IN HIGHS WITH LOW TO MID 90S EXPECTED BOTH DAYS WITH LITTLE RELIEF EXPECTED. BY SUNDAY NIGHT...THE EASTERN FRINGES OF THIS RIDGE BEGIN TO BREAK DOWN AND SHOWERS AND THUNDERSTORMS DEVELOP AHEAD OF A COLD FRONT EXPECTED MONDAY NIGHT INTO TUESDAY. THE GOOD NEWS IS THAT THIS COLD FRONT IS STILL IN ALL OF THE MEDIUM RANGE MODELS AND STILL FORECAST TO MOVE ACROSS MIDDLE TENNESSEE WITH VERY PLEASANT WEATHER FOR EARLY AUGUST EXPECTED AS MUCH DRIER AIR FILTERS INTO THE REGION. HIGHS TUESDAY THROUGH THURSDAY LOOK TO BE IN THE MID TO UPPER 80S WITH MARKEDLY LOWER HUMIDITY UNDER SUNNY SKIES...NOT A BAD SCENARIO AT ALL. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 83 69 86 68 / 100 20 10 10 CLARKSVILLE 84 67 85 67 / 70 20 10 0 CROSSVILLE 79 67 79 65 / 100 60 10 10 COLUMBIA 84 69 86 68 / 100 20 10 10 LAWRENCEBURG 84 69 87 69 / 90 20 10 10 WAVERLY 84 67 85 69 / 80 20 10 0 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 55
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
659 AM CDT THU AUG 6 2015 .AVIATION... UPPER LEVEL HIGH PRESSURE RIDGE WILL EXPAND FURTHER ACROSS THE SOUTHERN PLAINS REGION TODAY AND TONIGHT LEADING TO HOT AND MOSTLY DRY CONDITIONS. LINGERING MID LEVEL MOISTURE AND WEAK CONVERGENCE WITHIN A SURFACE TROUGH COULD LEAD TO ISOLATED HIGH-BASED THUNDERSTORMS LATER THIS AFTERNOON UNTIL EARLY THIS EVENING NORTH- NORTHWEST OF KLBB BUT POSSIBLY NEAR KPVW. COVERAGE EXPECTED TO BE TOO SPARSE FOR INCLUSION WITHIN THE KPVW TAF FOR NOW. RMCQUEEN && .PREV DISCUSSION... /ISSUED 357 AM CDT THU AUG 6 2015/ SHORT TERM... UPPER LEVEL HIGH PRESSURE WILL CONTINUE TO EXPAND ACROSS THE AREA TODAY AND TONIGHT. THIS WILL LEAD TO BETTER SURFACE WARMING WITH HIGHS TODAY A DEGREE OR MAYBE TWO WARMER FOR MOST OF THE AREA...AND SHOULD BE THE HOTTEST DAY OF SUMMER SO FAR. SURFACE MOISTURE STILL ELEVATED THOUGH WILL TREND DOWNWARDS DURING THE PEAK MIXING PERIOD THIS AFTERNOON...SO WILL ALSO LIMIT HEAT INDEX VALUES SOMEWHAT. WE REMAIN A BIT UNCERTAIN IF MODELS ARE CORRECTLY FORECASTING SURFACE DEWPOINT VALUES...AND IF UNDERPLAYED BY ONLY 2 OR 3 DEGREES MAY REQUIRE CONSIDERATION OF A HEAT ADVISORY IN THE SOUTHEAST CORNER OF OUR AREA. BUT FOR NOW WE SIDE WITH THE BULK OF OUR GUIDANCE WHICH COMES UP JUST SHORT OF HEAT ADVISORY LEVELS. WHILE THE UPPER RIDGE WILL CONTINUE TO EXPAND...CAPPING STILL LOOKS MARGINAL AND ACTUALLY FORECAST TO WEAKEN DURING PEAK DEEP MIXING ACROSS THE NORTHWEST CORNER OF OUR AREA. A SHORT WAVE PASSING BY TO THE NORTH WILL DRAG ANOTHER BATCH OF LIMITED MID LEVEL MOISTURE ACROSS THIS AREA THIS AFTERNOON AND EARLY EVENING. A SURFACE TROUGH ALSO WILL PROVIDE WEAK CONVERGENCE IN OUR NORTHWEST. SHORT RANGE SOLUTIONS OF RAP AND HRRR HAVE ONCE AGAIN BEEN INSISTENT TONIGHT ON ISOLATED TO WIDELY SCATTERED COVERAGE OF HIGH-BASED THUNDERSTORMS LATE THIS AFTERNOON INTO THE EARLY EVENING...ALTHOUGH LESS COVERAGE THAN EXPERIENCED YESTERDAY. SURFACE BASED CAPES APPEAR MOSTLY UNDER 1000 JOULES PER KILOGRAM LATER TODAY SO STORMS MAY HAVE A LITTLE LESS OOMPH AS WELL. EVEN SO...WE WILL INCLUDE A SLIGHT CHANCE FOR THUNDERSTORMS FOR LATER THIS AFTERNOON AND EARLY THIS EVENING IN OUR NORTHWEST CORNER. ANY STORMS SHOULD QUICKLY DISSIPATE WITH LOSS OF SURFACE HEATING EARLY THIS EVENING AND ANOTHER QUIET AND MILD NIGHT WILL FOLLOW. RMCQUEEN LONG TERM... FRIDAY AND INTO THE WEEKEND WILL REMAIN HOT...ALTHOUGH A COUPLE OF DEGREES COOLER THAN TODAY AS THE UPPER HIGH IS NUDGED EAST AHEAD OF A DISTURBANCE PUSHING ONSHORE CENTRAL CALIFORNIA. HIGH TEMPERATURES WILL REMAIN MOSTLY IN THE MID 90S TO NEAR THE CENTURY MARK ON THE CAPROCK WHILE LOCALES IN THE ROLLING PLAINS AND FAR SOUTHEAST PANHANDLE RESIDE IN THE UPPER 90S TO AROUND 104-105 DEGREES. LATE SUNDAY CONTINUES TO BEAR WATCHING IN TERMS OF ISOLATED THUNDERSTORM POTENTIAL NEAR THE FAR SOUTHWEST PANHANDLE INTO THE NORTHERN SOUTH PLAINS. ENERGY FROM THE PREVIOUSLY MENTIONED DISTURBANCE...AT THIS TIME ROTATING THROUGH THE NORTHERN PLAINS INTO THE UPPER MIDWEST...WILL SEND A FRONTAL BOUNDARY SOUTHWARD THROUGH THE PLAINS. AT THE SAME TIME...A SUBTROPICAL MOISTURE PLUME WILL ATTEMPT TO BEND EASTWARD ACROSS THE TEXAS/NEW MEXICO BORDER. WHETHER THIS ENHANCED MID-UPPER MOISTURE MAKES IT INTO THE LONE STAR STATE WILL DEPEND ON PLACEMENT OF THE UPPER HIGH AS LATER SUNDAY LOOKS TO BE THE TIME AT WHICH THIS FEATURE BEGINS RETROGRADING WESTWARD. BELIEVE ENOUGH CONSISTENCY HAS BEEN SHOWN AT THIS TIME TO WARRANT SLIGHT CHANCE MENTION ACROSS PARMER COUNTY...BUT WILL CONTINUE TO MONITOR SAID UNCERTAINTIES GOING FORWARD. HEADING INTO NEXT WEEK...UPPER HIGH STILL LOOKS TO BUILD WEST AND NORTHWEST WHILE AMPLIFYING...THUS SHIFTING THE H85 THERMAL RIDGE AXIS IN THE SAME DIRECTION AND KEEPING TEMPERATURES MAINLY IN THE 90S LOCALLY. CYCLONIC FLOW FROM EASTERN CANADA BACK INTO THE OHIO VALLEY LOOKS TO KEEP SOME SEMBLANCE OF A FRONTAL BOUNDARY IN PLACE AHEAD OF A SURFACE RIDGE PUSHING SOUTH THROUGH THE MISSISSIPPI VALLEY. NWP NOW SUGGESTING THAT A PERIOD OF CONTINUED UPSLOPE FLOW MAY THEREFORE BE IN THE OFFING FOR A PERIOD NEXT WEEK ALONG WITH CONTINUED ENHANCED MOISTURE TRAPPED UNDERNEATH THE UPPER HIGH. HAVE KEPT CONDITIONS DRY FOR NOW AFTER SUNDAY EVENING GIVEN THE UNCERTAINTY IN THE DETAILED SYNOPTIC EVOLUTION AND EXTENT/AMOUNT OF MOISTURE THAT WILL BE AVAILABLE. THUNDERSTORM CHANCES AND COOLER TEMPERATURES WOULD BE THE SENSIBLE WEATHER RESULTS IF THIS SCENARIO DOES INDEED PLAY OUT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 99 69 97 67 / 10 0 0 0 TULIA 99 70 98 69 / 10 10 0 0 PLAINVIEW 100 71 98 70 / 10 10 0 0 LEVELLAND 101 71 99 70 / 10 0 0 0 LUBBOCK 100 74 100 72 / 0 0 0 0 DENVER CITY 102 70 99 70 / 0 0 0 0 BROWNFIELD 101 71 99 71 / 0 0 0 0 CHILDRESS 104 76 104 75 / 0 0 0 0 SPUR 103 75 102 73 / 0 0 0 0 ASPERMONT 106 78 104 77 / 0 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/05
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
651 AM CDT THU AUG 6 2015 .AVIATION... INTERMITTENT MVFR CIGS FOR THE I-35 TAF SITES SHOULD LIFT TO VFR BY 13Z AT AUS AND 14Z AT SAT/SSF. TIMING IS BASED ON THE LAST FEW DAYS AND THE HRRR WHICH HANDLED THE ONSET OF MVFR CIGS BEST THIS MORNING DESPITE SIMULATING LOWER IFR CLOUD DECKS. THE MAIN FORECAST ISSUE PAST THE NEXT FEW HOURS WILL BE GUSTY SOUTHERLY WINDS UP TO 25 KTS FOR THE I-35 TAF SITES BETWEEN 2-6Z TONIGHT UNTIL LLJ DECOUPLES FROM THE SURFACE. MODEL GUIDANCE IS TRENDING TOWARDS MVFR CIGS DEVELOPING AGAIN AT SAT/SSF BRIEFLY TOMORROW MORNING...BUT LOW LEVEL MOISTURE AND ONSHORE FLOW SHOULD BE LESS THAN TODAY SO CONFIDENCE WAS TOO LOW TO INCLUDE AT THIS TIME. && .PREV DISCUSSION... /ISSUED 322 AM CDT THU AUG 6 2015/ SHORT TERM (TODAY THROUGH FRIDAY)... FOCUS FOR THE SHORT TERM...AND LIKELY THE NEXT FEW DAYS IS ON THE MAX TEMPS AND DEWPOINT TEMPERATURES RESULTING IN APPARENT TEMPS BRIEFLY REACHING OR EXCEEDING HEAT ADVISORY CRITERIA. THE COMPLICATION FOR TODAY IS WHILE CONFIDENCE IS FAIRLY HIGH THAT A FEW OBSERVATIONS WILL REACH THE REQUIRED 108 DEGREE HEAT INDEX CRITERION...THIS MAY ONLY BE BRIEF AS DEWPOINTS SHOULD DECREASE THROUGH THE AFTERNOON. THUS CONFIDENCE IN COUNTY WIDE...PERSISTENT ADVISORY LEVEL INDICES IS LOWER. MODEL VERIFICATION HAS BEEN IN THE 98-99 PERCENT RANGE ON BOTH MAX T AND MIN RH AND HAVE NOT DEVIATED WITH THIS PACKAGE. THE TIME AND SPATIAL EXTENT CONFIDENCE ISSUES...AS WELL AS INTEROFFICE COLLABORATION...LED TO THE DECISION TO CONTINUE WITH HANDLING THIS AFTERNOON WITH SPS AND HWO MENTIONS AND INCLUDING AREA SPECIFICITY. WILL ALSO BRIEF NEXT SHIFT ON THE POSSIBLE POTENTIAL FOR A SHORT FUSE ADVISORY SHOULD THE FORECAST NOT GO AS PLANNED. LONG TERM (FRIDAY NIGHT THROUGH WEDNESDAY)... THE SAME FORECAST QUESTIONS WILL COME INTO PLAY FOR THE NEXT FEW DAYS WITH INCREASING CONFIDENCE IN THE CHANCE FOR ADVISORIES TO BE ISSUED THIS WEEKEND. AGAIN...AS IN PREVIOUS FORECASTS...THE DAY THAT APPEARS THE HOTTEST OVER THE NEXT 5 DAYS IS SATURDAY. SOME SLIGHTLY LOWER SURFACE MOISTURE SUNDAY AND MONDAY MAY RESULT IN A DEGREE OR TWO OF...FOR LACK OF A BETTER WORD...RELIEF BUT ADVISORIES MAY STILL BE NEEDED REGARDLESS SINCE MAX TEMPS ALONE WILL FLIRT WITH CRITERIA. BY THE MIDDLE OF NEXT WEEK...A VERY SIMILAR SET UP TO LAST WEEKS BOUNDARY PASSAGE THAT RESULTED IN ISOLATED TO SCATTERED STORM DEVELOPMENT ACROSS THE CWA WILL DEVELOP. A SOUTHWARD COLD FRONT GENERATED BY TROUGHING OVER THE MS RIVER VALLEY WILL SPREAD WESTWARD AND POTENTIALLY IMPACT THE CWA FROM THE NORTHEAST WEDNESDAY AFTERNOON. WITH FORECAST SOUNDINGS SHOWING DRY ADIABATIC LAPSE RATES UP TO ABOUT 700 MB AND A VERY DRY LOW LEVEL ATMOSPHERE...THINK BOUNDARY INDUCED COMPRESSIONAL WARMING MAY RESULT IN RECORD HIGHS BEING REALIZED WEDNESDAY AFTERNOON...ESPECIALLY FOR THE AUSTIN AREA. AS FAR AS POPS GO...PWATS ARE IN THE 1.7-1.8 RANGE EVEN WITH THE VERY DRY LOW LEVEL ATMOSPHERE. INSTABILITY WILL BE MEAGER WITH THE DRY SURFACE AIR AND THE ECMWF KEEPS THE AREA DRY...BUT GFS ON THE OTHER HAND IS QUITE A BIT MORE BULLISH ON QPF DEVELOPMENT. BELIEVE THE BEST CHANCE FOR POPS WILL BE IF THE BOUNDARY CAN INTERACT WITH THE SEA BREEZE AND GENERATE ENOUGH LIFT FOR A FEW SHOWERS ACROSS THE EASTERNMOST ZONES AND COASTAL PLAINS. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 101 77 101 77 103 / 0 0 0 0 0 AUSTIN BERGSTROM INTL AIRPORT 100 75 100 75 102 / 0 0 0 0 0 NEW BRAUNFELS MUNI AIRPORT 101 75 101 76 103 / 0 0 0 0 0 BURNET MUNI AIRPORT 100 76 101 75 102 / 0 0 0 0 0 DEL RIO INTL AIRPORT 103 79 103 80 104 / 0 0 0 0 0 GEORGETOWN MUNI AIRPORT 100 77 101 76 103 / 0 0 0 0 0 HONDO MUNI AIRPORT 100 75 100 75 102 / 0 0 0 0 0 SAN MARCOS MUNI AIRPORT 100 76 100 76 102 / 0 0 0 0 0 LA GRANGE - FAYETTE REGIONAL 100 77 100 78 102 / 0 0 0 0 0 SAN ANTONIO INTL AIRPORT 100 78 100 77 102 / 0 0 0 0 0 STINSON MUNI AIRPORT 101 77 101 77 103 / 0 0 0 0 0 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...LH SYNOPTIC/GRIDS...TB3
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
258 PM CDT THU AUG 6 2015 .SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT HOT AND HUMID CONDITIONS HAVE CONTINUED AROUND THE NATURAL STATE TODAY WITH SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS PORTIONS OF CENTRAL ARKANSAS DURING THE DAY TODAY AND CONTINUING TO PUSH TO THE SOUTHEAST THROUGH THE AFTERNOON. THERE ARE SOME SLIGHT CHANCES THAT ADDITIONAL SHOWERS AND THUNDERSTORMS COULD DEVELOP THIS AFTERNOON...GENERALLY SOUTH OF THE INTERSTATE 40 CORRIDOR. HRRR AND WRF...HAVE CONTINUALLY SHOWED CHANCES FOR DEVELOPMENT THIS AFTERNOON...BUT BASED ON CURRENT SATELLITE TRENDS...COULD NOT JUSTIFY MORE THAN SLIGHT CHANCE POPS. TONIGHT...EXPECT SHOWERS AND THUNDERSTORMS TO ONCE AGAIN DEVELOP ACROSS NORTHWEST ARKANSAS IN RESPONSE TO AN UPPER LEVEL SHORTWAVE THAT WILL PUSH SOUTHEAST...WITH BEST CHANCES NORTH OF THE INTERSTATE 40 WEST OF LITTLE ROCK TO NORTH OF INTERSTATE 530. THIS WILL ONCE AGAIN KEEP TEMPERATURES SOMEWHAT LIMITED ACROSS NORTHERN ARKANSAS AGAIN ON FRIDAY. HOWEVER...TEMPERATURES WILL WARM ALONG THE ARKANSAS RIVER VALLEY AND TO THE SOUTHWEST ON FRIDAY WITH HEAT INDICES LIKELY TOPPING 110 DEGREES. AS A RESULT...HAVE GONE AND ISSUED AN EXCESSIVE HEAT WARNING ALONG THE ARKANSAS RIVER VALLEY. UPPER LEVEL RIDGE WILL BUILD INTO THE REGION FOR THE WEEKEND AND BRING EVEN HOTTER TEMPERATURES TO THE NATURAL STATE...WITH NO PRECIPITATION EXPECTED. AT THIS POINT...FELT CONFIDENT IN EXTENDING THE HEAT ADVISORY THROUGH SATURDAY...HOWEVER DID NOT EXTEND THE EXCESSIVE HEAT WARNING. WILL LET FUTURE SHIFTS MONITOR THE THREAT. && .LONG TERM...MONDAY THROUGH THURSDAY UPPER AIR PATTERNS ACROSS NORTH AMERICA ARE EXPECTED TO UNDERGO SUBTANTIAL AMPLIFICATION EARLY IN THIS PERIOD. A COLD FRONT WILL MOVE SOUTH THROUGH THE MID SOUTH EARLY IN THIS PERIOD. AT THIS TIME...PRECIPITATION AMOUNT SHOULD BE LIGHT. MAIN EFFECT OF THIS FEATURE WILL BE TO BRING AN AIR MASS WITH NEAR NORMAL TEMPERATURES. && .PRELIMINARY POINT TEMPS/POPS... BATESVILLE AR 71 89 74 92 / 50 20 20 10 CAMDEN AR 78 100 79 101 / 20 10 10 10 HARRISON AR 70 92 73 95 / 50 20 20 10 HOT SPRINGS AR 78 100 79 101 / 20 10 10 10 LITTLE ROCK AR 76 98 78 99 / 40 20 20 10 MONTICELLO AR 78 100 78 100 / 20 20 20 10 MOUNT IDA AR 75 100 75 100 / 10 10 10 10 MOUNTAIN HOME AR 70 90 74 94 / 50 20 20 10 NEWPORT AR 71 88 73 92 / 40 20 20 10 PINE BLUFF AR 76 98 76 99 / 30 20 20 10 RUSSELLVILLE AR 76 99 76 101 / 40 20 10 10 SEARCY AR 72 93 76 97 / 50 20 20 10 STUTTGART AR 75 95 76 96 / 40 20 20 10 && .LZK WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM CDT SATURDAY FOR BAXTER-BOONE- INDEPENDENCE-JACKSON-MARION-NEWTON-SEARCY-STONE. EXCESSIVE HEAT WARNING FROM NOON TO 7 PM CDT FRIDAY FOR BRADLEY- CALHOUN-CLARK-CLEVELAND-CONWAY-DALLAS-DESHA-DREW-FAULKNER- GARLAND-GRANT-HOT SPRING-JEFFERSON-JOHNSON-LINCOLN-LOGAN-LONOKE- OUACHITA-PERRY-POPE-PULASKI-SALINE-YELL. HEAT ADVISORY FROM NOON FRIDAY TO 7 PM CDT SATURDAY FOR ARKANSAS- CLEBURNE-CONWAY-DESHA-FAULKNER-JEFFERSON-JOHNSON-LINCOLN-LOGAN- LONOKE-MONROE-PERRY-POPE-PRAIRIE-PULASKI-SALINE-VAN BUREN-WHITE- WOODRUFF-YELL. HEAT ADVISORY UNTIL 7 PM CDT SATURDAY FOR BRADLEY-CALHOUN-CLARK- CLEVELAND-DALLAS-DREW-GARLAND-GRANT-HOT SPRING-MONTGOMERY- OUACHITA-PIKE-POLK-SCOTT. && $$ SHORT TERM...65 / LONG TERM...55
AREA FORECAST DISCUSSION
NWS TUCSON AZ
915 AM MST THU AUG 6 2015 .SYNOPSIS...HIGH PRESSURE WILL BEGIN TO SHIFT EAST OF THE AREA TODAY...BRINGING MOISTURE AND AN INCREASING THUNDERSTORM TREND BACK TO THE REGION THROUGH FRIDAY. AS THIS HAPPENS TEMPERATURES WILL FALL BACK CLOSER TO SEASONAL AVERAGES. WE WILL THEN KEEP ENOUGH MOISTURE FOR A FEW STORMS OVER THE WEEKEND WITH AN INCREASE EXPECTED AGAIN EARLY NEXT WEEK. && .DISCUSSION...THE COMPLEX AND OVERNIGHT DEVELOPMENT WE WERE EXPECTING LINGERED DEEPER INTO MORNING HOURS WITH A MORE ACTIVE DEBRIS FIELD THAN WE ANTICIPATED. THE REMNANT MCV FROM THE COMPLEX SOUTH OF THE BORDER CAN BE SEEN SWIRLING ALONG JUST SOUTHWEST OF TUCSON AT 9 AM. THE PERIPHERY OF THIS FEATURE WILL REMAIN ACTIVE AS IT CONTINUES NORTHWARD JUST WEST OF THE CITY. OTHERWISE...THE GULF SURGE AND DEEP CONVECTIVE OUTFLOW WE WERE EXPECTING IS HERE. THE 12Z KTWC SOUNDING IS VERY CONDUCIVE TO SHOWER AND THUNDERSTORM DEVELOPMENT WITH MODIFIED ML CAPE OVER 1K J/KG AND SOLID WIND PROFILE FOR STORM DEVELOPMENT. PRECIPITABLE WATER BACK OVER 1.5 INCHES. CIRA LPW SHOWS THE INCREASING MOISTURE TREND AT THE H7 TO H5 LAYER CONTINUED OVERNIGHT PUSHING DEEP INTO SOUTHERN ARIZONA WITH TOTALS RANGING FROM 1.2 TO 1.6 ACROSS THE AREA. THE QUESTION IS WILL WE BE ABLE TO TAKE ADVANTAGE OF THIS LATER TODAY? THE MORNING DEBRIS THROWS A WRENCH IN THE NORMAL DIURNAL DEVELOPMENT OF STORMS. LATEST HRRR AND UOFA WRF-NAM TRENDS VERY REASONABLY ARGUE FOR INHIBITED DEVELOPMENT FOR AREAS AFFECTED BY THIS MORNING`S ACTIVITY (INCLUDING THE TUCSON METRO). WE WILL LOOK SOUTH AND SOUTHEAST TO AREAS THAT SHOULD SEE BETTER SUNSHINE TODAY. AFTER STRONG REDEVELOPMENT ACROSS PORTIONS OF SANTA CRUZ AND SOUTHERN COCHISE COUNTY...WE WILL THEN SEE WHAT WE CAN PUSH NORTH AND NORTHWEST BACK TOWARD THE REST OF OUR CWA DURING THE LATE AFTERNOON AND EVENING HOURS. PLEASE SEE THE PREVIOUS DISCUSSION BELOW FOR ADDITIONAL DETAILS. && .AVIATION...VALID THRU 07/18Z. SCT-BKN CLOUDS AT 8-12K FT AGL AND BKN-OVC CLOUDS AOA 12K FT AGL WITH SCT SHRA AND ISOLD TSRA FROM TUCSON SOUTH AND WEST THRU 06/19Z. AFT 06/19Z SHRA/TSRA BECOMING MORE NUMEROUS STILL WITH A FOCUS ACROSS SOUTHERN AND WESTERN AREAS. BRIEF MVFR CONDITIONS AND ERRATIC WIND GUSTS TO 40 KTS PSBL IN AND NEAR STRONGER TSRA. SHRA/TSRA WILL DISSIPATE AFTER 06/05Z. OUTSIDE OF STORM INFLUENCES...SFC WINDS WILL GENERALLY BE LESS THAN 12 KTS WITH A FEW HIGHER GUSTS DURING THE AFTERNOON/EARLY EVENING HOURS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...INCREASING MOISTURE ARRIVING A BIT EARLIER THAN EXPECTED WILL RESULT IN AN UPSWING IN SHOWER AND THUNDERSTORM ACTIVITY TODAY AND FRIDAY. THE STRONGEST STORMS WILL BE CAPABLE OF A SHORT PERIOD OF INTENSE RAIN AND WIND GUSTS IN EXCESS OF 40 MPH. DECREASING PRECIPITATION CHANCES ARE THEN EXPECTED OVER THE WEEKEND...WITH MOST OF THE ACTIVITY ALONG THE INTERNATIONAL BORDER FROM NOGALES EASTWARD...AND ALONG THE NEW MEXICO BORDER. INCREASING COVERAGE WILL THEN BE ON TAP ACROSS THE FORECAST AREA NEXT WEEK. OUTSIDE OF THUNDERSTORM WIND GUSTS...20-FT WINDS WILL GENERALLY BE LESS THAN 15 MPH. HOWEVER...THERE WILL STILL BE SOME AFTERNOON AND EARLY EVENING BREEZINESS. && .PREV DISCUSSION...WHILE WE`RE CERTAINLY BEGINNING TO SEE A BETTER MOISTURE SIGNAL TO OUR SOUTH AND WEST...THERE ARE A COUPLE ISSUES TO CONTEND WITH FOR TODAY`S FORECAST AS THE MID-LEVEL HIGH SWINGS INTO NM. THE FIRST REVOLVES AROUND THE LEVEL OF CLEARING WE SEE OUT WEST. WHILE NAM/GFS SOUNDINGS SW OF TUCSON SHOW DECENT MUCAPE...IT`S ALL LOCKED UP ABOVE A STOUT NOSE OF +25C AIR AROUND 850 MB WHICH WILL REQUIRE SOLID DIABATIC HEATING TO TAP INTO TODAY. THE SECOND ISSUE...POSSIBLY A BIT LESS IMPORTANT...IS THE FLOW WHICH IS GENERALLY LIGHT AND PRETTY ILL-DEFINED BELOW 500 MB. HOWEVER...ALL NWP SOLUTIONS SHOW SOME KIND OF SUBTLE IMPULSE EMBEDDED IN THE MID- LEVEL FLOW WHICH MAY AUGMENT THE FLOW A TOUCH TODAY. BASED ON SATELLITE...RADAR TRENDS...AND HIRES NWP SOLUTIONS...FEEL WE WILL SEE ENOUGH CLEARING TODAY TO SET THE STAGE FOR GOOD CONVECTIVE COVERAGE SOUTH AND WEST OF TUCSON. IN ADDITION...OPTED TO CONTINUE PATCHY BLOWING DUST WORDING OVER PARTS OF CENTRAL/WESTERN PIMA COUNTY THIS AFTERNOON/EVENING WHERE THE LAND INFORMATION SYSTEM INDICATES RELATIVE SOIL MOISTURE VALUES DOWN NEAR 30-35 PCT. THESE VALUES ARE LIKELY TOO `MOIST` FOR WIDESPREAD AREAS OF DUST...BUT LOW ENOUGH TO CAUSE LOCAL VISIBILITY RESTRICTIONS ESPECIALLY GIVEN INDICATIONS OF POTENTIALLY STRONG GUSTY OUTFLOWS IN ANY STORMS THAT DO MANAGE TO FORM. NO BIG CHANGES FRIDAY AND INTO THE WEEKEND AS OUR POP VALUES ARE TRENDING VERY NICELY. COVERAGE SHOULD SHIFT EAST A TOUCH TOMORROW AND AGAIN SATURDAY AS THE MID-LEVEL HIGH MOVES INTO THE ARKLATEX REGION. AT THIS TIME...THE BEST SHOT AT STORMS FOR THE TUCSON AREA APPEARS TO BE ON FRIDAY...JUST AS THE MAIN SLUG OF MOISTURE BEGINS TO MOVE EAST OF AZ. THEN EARLY NEXT WEEK...MOISTURE WILL SLOSH BACK WEST AGAIN AS THE HIGH AMPLIFIES AND MOVES BACK TOWARDS THE NM/TX BORDER. BY WEDNESDAY AND THURSDAY...THE HIGH CENTER MAY GET CLOSE ENOUGH TO BEGIN SHUTTING ACTIVITY DOWN A TOUCH ONCE AGAIN. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...MEYER AVIATION/FIRE WEATHER...CERNIGLIA PREV DISCUSSION...CARLAW VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS RENO NV
127 PM PDT THU AUG 6 2015 .SYNOPSIS... NUMEROUS RAIN SHOWERS AND CHANCES FOR THUNDERSTORMS WILL DEVELOP TONIGHT THROUGH FRIDAY. THERE COULD ALSO BE A FEW LIGHTER SHOWERS OR THUNDERSTORMS SATURDAY AFTERNOON. DRY WEATHER RETURNS FOR THE START OF NEXT WEEK WITH AFTERNOON TEMPERATURES SLIGHTLY BELOW NORMAL. && .SHORT TERM... SATELLITE IMAGERY SHOWS A LOW-PRESSURE SYSTEM CURRENTLY SPINNING JUST OFFSHORE OF THE NORTHERN CALIFORNIA COAST. MODEL FORECASTS HAVE TRENDED A BIT LOWER WITH THE AMOUNT OF MOISTURE THAT REACHES THE SIERRA/WESTERN NV TONIGHT, BUT SATELLITE ESTIMATES STILL INDICATE A STREAM OF 1+ INCH ATMOSPHERIC MOISTURE (PW) VALUES ASSOCIATED WITH THIS SYSTEM. THE MAIN FORECAST CHALLENGE CONTINUES TO BE INSTABILITY, ESPECIALLY REGARDING THE POTENTIAL FOR THUNDERSTORMS AND LOCALLY HEAVIER RAIN. FAIRLY STABLE LAPSE RATES ARE EXPECTED TONIGHT OVERALL, BUT WITH STRONG FORCING OVER THE SIERRA WE CAN`T RULE OUT THE RISK OF THUNDERSTORMS WITH LITTLE RAIN ESPECIALLY ALONG THE NORTHERN FRINGE OF DEEPER MOISTURE. AS SUCH, A FIRE WEATHER WATCH IS IN EFFECT ROUGHLY FOR A REGION ALONG THE SIERRA FROM MARKLEEVILLE TO TAHOE TO PLUMAS COUNTY. SEE THE FIRE WEATHER DISCUSSION BELOW FOR DETAILS. FOR FRIDAY AFTERNOON, THE THREAT FOR STRONG TO SEVERE THUNDERSTORMS HAS DECREASED COMPARED TO YESTERDAY. THE STRONGEST FORCING AND VERTICAL WIND SHEAR SHOULD SHIFT EAST OF MINERAL/PERSHING/CHURCHILL COUNTIES BY AFTERNOON. AS SUCH, THE MOST LIKELY SCENARIO FOR FRIDAY IS NUMEROUS SHOWERS WITH ISOLATED EMBEDDED THUNDERSTORMS. THERE IS STILL A GOOD CHANCE FOR MANY LOCATIONS TO RECEIVE AT LEAST 0.10 INCH RAIN, BUT WITH A FAIRLY STABLE AIR MASS THE CHANCES FOR RECEIVING GREATER THAN 0.50 INCHES ARE LIMITED. HOWEVER, THE RISK FOR FLASH FLOODS AND SEVERE STORMS IS LOW BUT NOT ZERO, ESPECIALLY IF THERE ARE ANY CLOUD BREAKS. FOR SATURDAY, THERE ARE SLIGHT CHANCES FOR THUNDER NORTH OF PORTOLA-PYRAMID LAKE-FALLON AS A WEAK UPPER WAVE COULD TRIGGER A FEW GARDEN VARIETY THUNDERSTORMS. JCM .LONG TERM...SUNDAY THROUGH THURSDAY... NO SIGNIFICANT CHANGES TO THE LONG TERM FORECAST TODAY. BY SUNDAY LOW PRESSURE DROPPING SOUTH OUT OF THE GULF OF ALASKA WILL BE CENTERED OFF THE COAST OF BRITISH COLUMBIA AS HIGH PRESSURE BUILDS OVER THE ROCKIES. GENERALLY EXPECTING NEAR NORMAL TEMPERATURES NEXT WEEK WITH DRY SOUTHWEST FLOW AND TYPICAL AFTERNOON ZEPHYR WINDS. STRONGER ZEPHYR WILL BE POSSIBLE STARTING ON TUESDAY, BUT MORE LIKELY ON WEDNESDAY OR THURSDAY. COMBINED WITH LOW RH, FIRE WEATHER COULD BECOME A CONCERN LATER IN THE WEEK, ESPECIALLY IF CONSIDERABLE LIGHTNING STRIKES TONIGHT CREATE THE POSSIBILITY OF HOLD OVER FIRES. CONFIDENCE IS LOW RIGHT NOW FOR WHICH DAY NEXT WEEK WOULD HAVE THE STRONGEST WINDS AS MODELS DIVERGE CONSIDERABLY GOING INTO NEXT WEEK ON THE STRENGTH AND POSITION OF THE LOW PRESSURE. TOLBY && .AVIATION... VFR CONDITIONS TODAY WITH WSW WINDS GUSTING TO 20KTS AND REDUCED SLANTWISE VISIBILITY DUE TO SMOKE AND HAZE FROM THE DODGE FIRE IN THE NORTHERN SIERRA. HAZE IS CURRENTLY EVIDENT FROM THE OREGON BORDER DOWN TO THE RENO/CARSON CITY AREA AND OUT PAST FALLON. EXPECT HAZE TO BEGIN MIXING OUT WITH THE AFTERNOON WESTERLIES AFTER 00Z. THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON ALONG THE SIERRA CREST IN MONO COUNTY AFTER 00Z. THE THREAT OF THUNDERSTORMS MOVES INTO THE CENTRAL SIERRA STARTING AROUND 05Z AND INTO CENTRAL WESTERN NEVADA BY 09Z. HOWEVER, CONFIDENCE IS LOW IN THE AMOUNT OF THUNDERSTORM ACTIVITY OVERNIGHT. AN ALTERNATE SCENARIO WOULD BE WIDESPREAD STRATIFORM RAIN SHOWERS WITH ONLY A FEW ISOLATED STORMS EMBEDDED. TOLBY && .FIRE WEATHER... THIS REMAINS A LOW-MEDIUM CONFIDENCE SITUATION WITH RESPECT TO DRY THUNDERSTORM POTENTIAL THIS EVENING AND TONIGHT. CONFLICTING SIGNALS IN LATEST GFS GUIDANCE (SHEAR/LIFT VS INSTABILITY ALOFT VS PRECIP WATER), AND HRRR SHOWING MAINLY JUST SHOWERS DEVELOPING WITH APPROACHING UPPER WAVE. CLOUD COVER IS RATHER THICK, EXTENDING OFF THE CA COASTLINE, WHICH IS LIMITING HEATING TODAY AND LAPSE RATES ALOFT. WE FEEL THERE IS STILL SUFFICIENT RISK OF A FEW DRY STORMS THIS EVE AND TONIGHT IN THE SIERRA FROM ROUGHLY SONORA PASS TO SUSANVILLE TO CONTINUE THE FIRE WEATHER WATCH. OUR CONFIDENCE IS NOWHERE NEAR SUFFICIENT HOWEVER TO UPGRADE TO A RED FLAG WARNING. STORMS COULD TURN WET QUITE QUICKLY AS UPPER LOW APPROACHES AFTER MIDNIGHT BUT FREQUENT LIGHTNING CAN RESULT IN NEW FIRE STARTS OUTSIDE RAIN CORES. A TRANSITION TO WIDESPREAD SHOWERS AND ISOLATED THUNDER IS ANTICIPATED AREAWIDE AFTER 9-12Z/FRI SO THE WATCH WILL END THEN. HEADS UP FOR NEXT WEEK, WHERE PATTERN BECOMES DRY WITH BREEZIER SW FLOW AS UPPER LOW LOOKS TO PARK OFF THE CA/OR COASTLINE. IF WE HAVE APPRECIABLE LIGHTNING TONIGHT OR TOMORROW, THESE CONDITIONS NEXT WEEK COULD PROMOTE THE DEVELOPMENT OF HOLDOVER FIRES. CS && .REV WATCHES/WARNINGS/ADVISORIES... NV...CA...FIRE WEATHER WATCH FROM 6 PM PDT THIS EVENING THROUGH LATE TONIGHT CAZ271>273. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
331 PM EDT THU AUG 6 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL DEVELOP ALONG A STALLED FRONT TO OUR SOUTH, THEN SLOWLY MOVE THE COAST OF THE NORTH CAROLINA COAST LATE FRIDAY INTO SATURDAY. THE LOW IS THEN FORECAST TO MOVE NORTHWARD OVER THE WESTERN ATLANTIC, WHILE HIGH PRESSURE BUILDS IN FOR THE WEEKEND. ANOTHER COLD FRONT IS EXPECTED TO CROSS THE AREA EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... LOW PRESSURE ACROSS KENTUCKY WILL CONTINUE TO MOVE EAST INTO VIRGINIA TONIGHT ALONG A FRONT. CLOUDS WILL CONTINUE TO INCREASE FROM SOUTHWEST TO NORTHEAST ACROSS THE REGION. MOISTURE WILL CONTINUE TO ADVECT NORTH OF THE FRONTAL BOUNDARY AS WELL ALLOWING THE AREA OF SHOWERS LOCATED IN THE OHIO VALLEY TO MOVE EAST OVERNIGHT. HOWEVER, HIGH PRESSURE OVER SOUTHEAST CANADA AND NEW ENGLAND HAS FACTORED INTO THE TRACK OF THE LOW PRESSURE TRENDING FURTHER SOUTH WITH RECENT MODEL RUNS. THIS PUSHES THE RAIN/ NO RAIN CUTOFF TO ABOUT PHILADELPHIA, WITH THE HIGHEST COVERAGE OF SHOWERS IN DELMARVA. IN TERMS OF TIMING, THE HRRR AND RAP MODELS KEEP THE BEST CHANCE AROUND OR JUST AFTER MIDNIGHT. HOWEVER, A FEW SHOWERS COULD BE AROUND THE WHOLE NIGHT. STAYED CLOSE TO STAT GUIDANCE TONIGHT. LOWS WILL BE WARMER WITH THE THICKER CLOUDS IN DELMARVA IN THE LOW 70`S WITH 60`S AND EVEN SOME 50`S FURTHER NORTHWEST. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/... THE LOW PRESSURE SYSTEM WILL MOVE OFFSHORE ON FRIDAY. CLOUDS AND SHOWERS ARE STILL LIKELY IN DELMARVA. WITH LITTLE PRECIPITATION FROM PHILADELPHIA TO THE NORTHWEST. TOTAL QPF HAS ALSO DECREASED WITH THE SOUTHERN TRENDS ON ALL THE OPERATIONAL MODEL RUNS. WENT WITH THE DRIER SREF GIVEN THE 12Z MODELS TODAY, WHICH HAS TOP RAINFALL TOTALS AROUND A HALF INCH IN SOUTHERN DELAWARE. HIGH TEMPERATURES IN SUNNY AREAS AWAY FROM THE SOUTHERN JERSEY SHORE AND DELMARVA WILL WARM INTO THE 80`S. FURTHER SOUTHEAST, WHERE CLOUDS AND SHOWERS OCCUR, THE FORECAST IS LOWER THAN THE MET/MAV GUIDANCE SETS WITH HIGHS IN THE 70`S. SOME UNCERTAINTY STILL REMAINS OVER THE EXACT RAIN/NO RAIN LINE TONIGHT AND FRIDAY. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... AN AREA OF LOW PRES WILL BE MOVG TO OUR S AT THE START OF THE PD. LTST MDL RUNS HAVE ALL TRENDED S THIS CYCLE. FOR NRN AREAS, THERE WILL BE NO PRECIP, CENTRAL AREAS, LITTLE, IF ANY AND FOR SRN AREAS, QPF HAS DECREASED. GUIDANCE HAS ALSO SPED THE ENDING OF THE PRECIP UP WITH THE RAIN BEING OVER MOST EVERYWHERE DURG SAT NIGHT. THE ONLY EXCEPTION IS ALG THE DELMARVA AND PSBLY EXTREME SERN NJ, WHERE THERE CUD BE SOME PRECIP LINGERING INTO THE DAY ON SAT. THE LOW PRES WILL MOV NE WELL OUT TO SEA AS WEAK HIGH PRES BUILDS IN FOR SUN, BRINGING WHAT SHUD BE A NICE DAY. THEN, BY MON THERE ARE SOME TIMING DIFFS WRT TO SOME PRECIP IN ADVANCE OF A FRONT APPROACHING FROM THE W. THE GFS IS ESSENTIALLY DRY ON MON. THE CMC BRING A CDFNT TO THE WRN AREAS DURG THE DAY. THE ECMWF KEEPS THE CDFNT TO THE W BUT BRINGS SOME PREFRONTAL PRECIP DURG THE DAY, SO FOR NOW WILL JUST GO WITH SOME LOW POPS. MON NIGHT LOOKS TO BE MAINLY DRY, THEN BOTH THE GFS AND ECMWF BRING THE CFP ON TUE, WHICH, BASED ON CURRENT TIMING, WOULD BE THE WETTEST PD...MOST LIKELY TUE AFTN/EVE. BEHIND THE FRONT, SFC HIGH PRES AND YET ANOTHER H5 RIDGE MOVE OVER THE REGION. TEMPS LOOK TO BE RIGHT AROUND TO SLIGHTLY BELOW NRML THRU THE PD, WITH GENLY PLEASANT HUMIDITY VALUES. && .AVIATION /19Z THURSDAY THROUGH TUESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR THROUGHOUT THE WHOLE PERIOD WITH SOME TEMPORARY MVFR CONDITIONS POSSIBLE FOR KACY, KMIV AND KILG. CLOUDS WILL CONTINUE TO GRADUALLY THICKEN AND LOWER TONIGHT TO AROUND 5,000 FEET IN MOST SPOTS. SOME SPOTTY SHOWERS ARE POSSIBLE AT TIMES FROM KILG AND SITES SOUTHEAST. THE BEST CHANCE FOR ANY BRIEF CEILING OR VISIBILITY RESTRICTION WILL BE AT KACY WHERE MVFR CONDITIONS ARE FORECASTED FOR A TIME OVERNIGHT. ON FRIDAY, AWAY FROM KACY CEILINGS SHOULD BEGIN TO LIFT AND BREAK UP. WINDS ARE EXPECTED TO BE UNDER 10 KNOTS AND VARIABLE TONIGHT BECOMING STRONGER OUT OF THE EAST-NORTHEAST WITH GUSTS TO 20 KNOTS IN THE AFTERNOON HOURS ON FRIDAY. OUTLOOK... FRI NIGHT...MVFR/IFR CONDITIONS PSBL ERLY, ESPECIALLY SE. OTRW, VFR EXPECTED. IMPROVING CONDS WITH TIME. SOUTHERN AREAS WITH RAIN POSSIBLE. GENERALLY VFR ACROSS THE NORTH. NE WIND 10 TO 20 KTS PSBL SERN AREAS. LOW TO MDT CONFIDENCE. SAT-SUN...VFR. NE WIND 15 TO 25 KTS, ESPECIALLY ALONG THE COAST DURING THE DAY. MDT CONFIDENCE MON...VFR. SOME MVFR/IFR PSBL IN MAINLY DIURNAL SHRA/TSRA. NE WIND 10 TO 20 KTS. LOW TO MDT CONFIDENCE. && .MARINE... AFTER A MAINLY TRANQUIL NIGHT, SEAS WILL INCREASE ON FRIDAY. THEY WILL LIKELY RISE TO AROUND FOUR FEET LATE IN THE DAY. SOME EAST- NORTHEAST WIND GUSTS MAY APPROACH 25 KNOTS AS WELL BY SUNSET AS A DEVELOPING LOW PRESSURE SYSTEM FORMS TO OUR SOUTHEAST. OUTLOOK... FRI NIGHT...WINDS AND SEAS WILL INCREASE AND AN SCA WILL BE NEEDED BY FRI NIGHT, IF NOT SOONER. SAT-SUN...WINDS AND SEAS EXPECTED TO REMAIN ABOVE SCA CRITERIA. SUN NIGHT-MON...SEAS ARE EXPECTED TO REMAIN AROUND 5 FT, WHILE WIND DROPS BELOW ADVISORY CRITERIA ON MONDAY. && .TIDES/COASTAL FLOODING... THE LATEST MODEL GUIDANCE SUGGESTS THE LOW PRESSURE SYSTEM FROM THE LOWER OHIO RIVER VALLEY WILL EXHIBIT A SLIGHTLY MORE SOUTHERN TRACK, WHICH WOULD RESULT IN JUST SPOTTY TO MINOR TIDAL FLOODING. THIS GUIDANCE ALSO SUGGESTS THE AREAS MOST SUSCEPTIBLE SO SUCH FLOODING WOULD BE DELAWARE AND SOUTHERN NEW JERSEY DURING THE SATURDAY AFTERNOON TIDAL CYCLE. && .RIP CURRENTS... BUILDING SEAS FRIDAY TO AROUND FOUR FEET AND INCREASING WINDS TO AROUND 20 KNOTS MAY LEAD TO INCREASING RIPS IN THE MODERATE CATEGORY BY FRIDAY AFTERNOON. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...NIERENBERG NEAR TERM...GAINES SHORT TERM...GAINES LONG TERM...NIERENBERG AVIATION...GAINES/NIERENBERG MARINE...GAINES/NIERENBERG TIDES/COASTAL FLOODING...MIKETTA RIP CURRENTS...GAINES
AREA FORECAST DISCUSSION
NWS JACKSON KY
1208 PM EDT THU AUG 6 2015 .UPDATE... ISSUED AT 1207 AM EDT THU AUG 6 2015 NEEDED TO MAKE A FEW ADJUSTMENTS TO THE FORECAST FOR THE REST OF TODAY. CURRENT RADAR TRENDS HAVE BEEN SHOWING A STEADY DECREASE IN AREAL COVERAGE OF SHOWERS AND STORMS THAT PAST FEW HOURS. IT APPEARS THAT A COMPLEX OF THUNDERSTORMS CURRENTLY MOVING ACROSS TENNESSEE MAY BE SAPPING ENERGY FROM THE PRECIPITATION THAT IS ONGOING ACROSS EASTERN KENTUCKY. UPSTREAM RADAR OBS ALSO SHOWING THIS SAY DECREASE IN PRECIP. THE HRRR MODEL SEEMS TO HAVE A DECENT ON THIS SITUATION...ESPECIALLY COMPARED TO THE NAM12 WHICH HAS PRETTY MUCH 100 PERCENT COVERAGE OF PRECIP ACROSS ALL OF EASTERN KENTUCKY FOR THE REST OF THE DAY. THE UPDATED FORECAST GRIDS AND ZONE FORECAST TEXT PRODUCT WERE UPDATED TO REFLECT CURRENT TRENDS. THE OTHER CHANGE MADE WAS TO CONTINUE TO SHOW AN INCREASE IN PRECIPCOVERAGE LATE THIS AFTERNOON AND EVENING...AS A SHORT WAVE ALOFT AND AN AREA OF SURFACE LOW PRESSURE BOTH MOVE ACROSS THE OHIO AND TENNESSEE VALLEY AREAS. EVEN THOUGH WE ARE EXPERIENCING A LULL IN THE ACTION...THE MODELS ALL ARE IN GOOD AGREEMENT THAT AN UPTICK IN SHOWER AND STORM ACTIVITY WILL OCCUR LATER THIS AFTERNOON. THE OTHER CHANGE MADE WAS TO DECREASE THE COVERAGE OF THUNDERSTORMS OVERALL...AS INSTABILITY IS A BIT LACKING DUE TO THE COOLER TEMPERATURES AND LACK OF SUN. THAT ALL BEING SAID...WENT WITH A GENERAL 80 PERCENT CHANCE OF RAIN THROUGH 0Z THIS EVENING...AS OPPOSED TO THE PREVIOUS 90 TO 100 POP...TO REFLECT THE CURRENT DOWNWARD TREND IN PRECIP AND THE LATEST HRRR MODEL OUTPUT. THEREFORE...THE QPF...POP...POP12...AND WEATHER TYPE GRIDS WERE ALL UPDATED TO REFLECT THE LATEST THINKING. SOME MINOR ADJUSTMENTS WERE ALSO MADE TO THE HOURLY TEMPERATURES...DEWPOINTS...AND HUMIDITY GRIDS...BUT NOTHING THAT WARRANTED UPDATING IN THE TEXT FORECAST PRODUCT. THE NEW ZONES HAVE ALREADY BEEN ISSUED. UPDATE ISSUED AT 813 AM EDT THU AUG 6 2015 PRECIPITATION IS FILLING IN AS SCHEDULED ACROSS THE AREA. SO FAR...THUNDERSTORMS HAVE BEEN MORE ISOLATED...HOWEVER THESE SHOULD BECOME MORE NUMEROUS THROUGH THE MIDDLE OF THE DAY AS BETTER FORCING ARRIVES FROM THE WEST. FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS...AND POPS TO ALIGN WITH THE CURRENT OBSERVATIONS AND RADAR TRENDS. && .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 352 AM EDT THU AUG 6 2015 LATEST SURFACE MAP FEATURES LOW PRESSURE NEAR THE IL/MO BORDER...WITH A FRONT WARM FRONT DRAPED TO THE EAST ACROSS KENTUCKY. ALOFT...A SHORT WAVE TROUGH IS ROTATING ACROSS THE OHIO VALLEY. CONVECTION OVERNIGHT HAS MAINLY BEEN CONFINED TO OUR WEST...WHERE A MODEST 850 MB LOW JET IS POISED. A LARGER COMPLEX OF STORMS ALSO DEVELOPED ACROSS ARKANSAS AND PUSHED EAST AND SOUTHEAST WHILE WEAKENING. THE MODELS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM...GRADUALLY BRINGING THE SHORT WAVE TROUGH AND REFLECTIVE SURFACE LOW ACROSS KENTUCKY THROUGH TONIGHT. EXPECT PRECIPITATION COVERAGE TO INCREASE AND INTENSIFY THROUGH THE DAY. LOWER INSTABILITY AND HIGHER MOISTURE CONTENT WILL ALLOW FOR EFFICIENT RAINERS TODAY INTO TONIGHT...AND FLASH FLOODING WILL CONTINUE TO BE A CONCERN...ESPECIALLY WHERE STORMS CAN TRAIN ACROSS THE SAME LOCATIONS. AS LOW PRESSURE PIVOTS AWAY LATER TONIGHT...PRECIPITATION WILL BE DIMINISHING FROM WEST TO EAST. A FEW SHOWERS MAY LINGER IN THE EAST ON FRIDAY...WITH UPPER LEVEL RIDGING GRADUALLY WORKING IN FROM THE SOUTHWEST LATER IN THE DAY. HIGHS WILL AVERAGE BELOW NORMAL OVER THE NEXT FEW DAYS...WITH MOST LOCATIONS LIKELY REMAINING IN THE 70S TODAY GIVEN THE PRECIPITATION AND CLOUD COVER AROUND. ON FRIDAY...READINGS WILL RECOVER A BIT MORE...WITH MOST PLACES SEEING AROUND THE 80 DEGREE MARK. .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 352 AM EDT THU AUG 6 2015 THE EXTENDED PORTION OF THE FORECAST BEGINS ON FRIDAY NIGHT WITH AN ACTIVE UPPER LEVEL PATTERN IN PLACE. THIS FEATURES A SET UP WITH A RIDGE OVER THE WESTERN CONUS WITH THE AXIS MEANDERING JUST WEST OF THE FRONT RANGE OF THE ROCKIES AND A TROUGH OVER THE EAST. OVERALL THE MODELS HAVE BEEN IN GOOD AGREEMENT WITH THE BROAD LONGWAVE PATTERN. THE UPPER LEVEL TROUGH SHIFTS EASTWARDS A BIT AS A SHORTWAVE SLIDES JUST NORTHEAST OF EASTERN KENTUCKY TO START THE PERIOD ON SATURDAY BUT AS THE TROUGH BEGINS TO DEEPEN AGAIN ANOTHER WAVE TAKES A MORE DIRECT TRACK OVER ALL OF KENTUCKY ON SUNDAY AS IT TRAVELS THE RIDGE AND INTO THE REGION. DURING THE MONDAY AFTERNOON AND INTO MONDAY NIGHT TIME FRAME...A MUCH MORE POTENT WAVE TRACKS OVER THE RIDGE AND THE NORTHERN PLAINS AND EVENTUALLY INTO THE OH VALLEY LATE MONDAY NIGHT INTO TUESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 813 AM EDT THU AUG 6 2015 LIFR OR WORSE FOG WILL MIX OUT AS SHOWERS AND SCATTERED THUNDERSTORMS MOVE IN FROM THE WEST. MAINLY MVFR CONDITIONS WILL BE SEEN THROUGH THE MORNING...BEFORE LIKELY DROPPING TO IFR IN THE AFTERNOON AS MORE SUSTAINED CONVECTION ARRIVES FROM THE WEST OUT AHEAD OF AN AREA OF LOW PRESSURE MOVES ACROSS THE OHIO VALLEY. CEILINGS WILL REMAIN LOW END MVFR WITH VISIBILITIES IN THE IFR RANGE AT TIMES. ONCE CONVECTION BEGINS TO DIMINISH FROM WEST TO EAST THIS EVENING...IFR STRATUS LOOKS TO FILL IN BEHIND DEPARTING LOW PRESSURE. IN GENERAL...WINDS WILL REMAIN AT AROUND 5 KTS OR LESS THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ044-050>052- 058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...AR SHORT TERM...GEOGERIAN LONG TERM...SHALLENBERGER AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
329 PM EDT THU AUG 6 2015 .SYNOPSIS... WHILE HIGH PRESSURE REMAINS OVER THE GREAT LAKES...A LOW PRESSURE SYSTEM IN THE OHIO VALLEY WILL TRAVEL EAST ALONG A STATIONARY FRONT TO OUR SOUTH TONIGHT AND FRIDAY. THE LOW WILL SLOWLY MOVE OFF THE CAROLINA COAST SATURDAY. WEAK HIGH PRESSURE WILL BUILD SOUTHWARD SUNDAY AND MONDAY BEFORE A COLD FRONT MOVES IN FROM THE NORTHWEST ON TUESDAY. && .NEAR TERM /THROUGH FRIDAY/... SFC LOW AND COMPACT UPPER DISTURBANCE CONTINUE TO TRACK SLOWLY EASTWARD THROUGH THE MID OHIO VALLEY THIS AFTERNOON. LIGHT TO MODERATE SHOWERS ARE SPREADING AHEAD OF THIS SYSTEM AND HAVE SPREAD INTO THE WESTERN CWA. HAVE RELIED ON THE HRRR AND RAP IN TERMS OF EVOLUTION AS THE SYNOPTIC MODELS DO NOT SEEM TO HAVE A GOOD HANDLE ON THE NORTHWARD EXTENT OF THIS RAIN. NEVERTHELESS...THE EVENT AS A WHOLE APPEARS LIGHTER AND MORE SOUTHWARD IN TERMS OF QPF DISTRIBUTION COMPARED TO PREVIOUS FORECASTS. INSTBY IS LIMITED TO FAR SOUTHERN MD...AND HEAVIER SHOWERS MOVING INTO THE LOWER BAY ARE INDICATIVE OF THIS ENVIRONMENT. OUTSIDE OF THIS AREA...POSSIBLY EXTENDING SOUTHWESTWARD TO NELSON COUNTY...THUNDER IS NOT EXPECTED. EXPECT THE SHIELD OF RAIN TO CONTINUE TO MOVE EASTWARD THROUGH THE EVENING AND OVERNIGHT. MOST AREAS WILL SEE RAIN AT SOME POINT...ALTHOUGH THE NORTHERN EDGE MAY GRADUALLY ERODE AND LEAVE LOCATIONS NEAR THE MASON-DIXON LINE DRY AT SOME POINT...ALTHOUGH THIS IS OF LOWER CONFIDENCE. PWATS WILL BE HIGH ENOUGH (NEAR TWO INCHES SOUTH OF I-66) TO PRODUCE A SOAKING RAIN...ESPECIALLY FOR SOUTHERN AREAS. HOWEVER DO NOT THINK THERE WILL BE THE CONVECTIVE ELEMENTS NEEDED NOR THE STRONG SYNOPTIC FORCING TO PRODUCE SHORT TERM RUNOFF ISSUES. THERE ARE INDICATIONS LATE TONIGHT AS THE LOW BEGINS TO STRENGTHEN AND SOME UPPER ENERGY APPROACHES...THAT THERE COULD BE SOME ENHANCED RAINFALL IN CENTRAL VA. WILL LEAVE A MENTION OF LOCALIZED FLOODING IN THE HWO. LOWS TONIGHT IN 60S WITH PERHAPS SOME LOWER 70S. SPECIFIC DETAILS ARE STILL NOT OF THE HIGHEST CONFIDENCE HEADING INTO FRIDAY AS MODEL DIFFERENCES REMAIN AS THE LOW REACHES A PIVOT POINT IN THE EASTERN CAROLINAS. CONFIDENCE HIGHEST IN RAINFALL...AND PERHAPS AN ISOLATED STORM...SOUTH AND EAST OF DC. HOWEVER A CHANCE OF SHOWERS COULD EXTEND BACK TOWARD THE SOUTHERN SHENANDOAH VALLEY. THERE SHOULD BE A GRADUAL DRYING TREND FROM THE NORTHWEST THROUGH THE DAY THOUGH. HIGH TEMPERATURES WILL BE BELOW NORMAL...GENERALLY IN THE 70S TO LOWER 80S...BUT WILL LIKELY DEPEND ON THE DURATION OF RAIN. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... EXPECT MOST PRECIP TO BE MOVING OUT OF CWA BY LATE EVENING FRIDAY...THE ONLY EXCEPTION WOULD BE FAR SOUTHERN MARYLAND WHERE SHOWERY ACTIVITY COULD LINGER INTO THE OVERNIGHT FOR A FEW HOURS. SFC LOW MOVES TO OUR EAST FOR THE WEEKEND...KEEPING US DRY AND FAIRLY MILD FOR EARLY AUGUST. TEMPS EXPECTED TO REMAIN A FEW DEGREES BELOW NORMAL...WITH DEWPOINTS IN L60S. OVERALL...IT SHOULD BE A RATHER BENIGN WEATHER WEEKEND. THE ONLY FLY IN THE OINTMENT WOULD BE THE LOW CHANCE OF A MOUNTAIN SHOWER OR T-STORM LATE SUNDAY RESULTING FROM TERRAIN CIRCULATIONS...THOUGH OVERALL COVERAGE SHOULD BE MINIMAL. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... BY MONDAY THE NEXT SYSTEM WILL BEGIN TO APPROACH FROM THE WEST...WHICH IS DEPICTED BY THE GFS...GGEM...AND ECMWF...BUT MUCH FASTER ON THE GGEM AND GFS. EXISTING FORECAST HAD WIDESPREAD CHANCE POPS...WHICH DESPITE THE SLOWER SOLUTION THE ECMWF FAVORS ANYWAY. BOTTOM LINE...WE MAINTAINED THIS. ON TUESDAY THE ECMWF ALMOST CATCHES UP WITH THE GFS WITH THE NEXT SYSTEM...WITH THE GFS SLOWING DOWN WITH IT. GGEM ON THE OTHER HAND KEEPS GOING FAST AND SENDS THE SYSTEM OFF THE COAST ALREADY. FORECAST ON THIS DAY HAS MOST CONFIDENCE AT PRESENT GIVEN THE SYSTEM TIMING IS AT LEAST A BIT CLOSER...BUT GIVEN DISCONTINUITIES EARLIER IN THE PERIOD UNCERTAINTY IS STILL RATHER LARGE. BY WEDNESDAY THE GFS PUSHES THE SYSTEM OFF THE COAST...WHILE THE SLOWER ECMWF GENERATES A COASTAL LOW OF RATHER IMPRESSIVE STRENGTH FOR AUGUST. AGAIN...STAYED FAIRLY CLOSE TO CONTINUITY WITH A DRYING FORECAST...BUT CONFIDENCE IS QUITE LOW. && .AVIATION /19Z THURSDAY THROUGH TUESDAY/... LOW PRESSURE WILL TRACK SOUTH OF THE AREA TONIGHT INTO FRIDAY. RAIN IS SPREADING INTO THE AREA FROM THE WEST. LIGHT SHOWERS WILL OVERSPREAD THE TERMINALS THROUGH LATE AFTERNOON...WITH A PERIOD OF MODERATE RAINFALL POSSIBLE OVERNIGHT. THE DURATION IS SOMEWHAT IN QUESTION...AS WELL AS HOW FAR NORTH THE HEAVIEST RAIN AND AVIATION IMPACTS REACH. MVFR CONDITIONS WILL BE POSSIBLE AT ALL TERMINALS...WITH THE CHANCE OF IFR GENERAL LIMITED TO NEAR OR SOUTH OF DC. RAIN MAY LINGER INTO THE MORNING AND AT THIS TIME IT IS UNCERTAIN HOW QUICKLY IT WILL EXIT ON FRIDAY. HOWEVER THERE IS A PRETTY GOOD CHANCE VFR WILL RETURN BY AFTERNOON. WINDS WILL REMAIN UNDER 10 KT THROUGH THE TAF PERIOD. VFR EXPECTED AT ALL TERMINALS BY FRIDAY NIGHT...AS PRECIP ASSOCIATED WITH LOW PRESSURE MOVES TO OUR EAST. VFR CONDS THEN EXPECTED THROUGH SUNDAY UNDER HIGH PRESSURE. NEXT CHANCE FOR SUB-VFR ARRIVES MONDAY AS A COLD FRONT APPROACHES MONDAY/TUESDAY ALONG WITH INCREASED RISK OF SHRA/TSRA. && .MARINE... LOW PRESSURE WILL PASS SOUTH OF THE AREA TONIGHT INTO FRIDAY. WHILE THERE COULD BE A THUNDERSTORM OVER SOUTHERN PORTIONS OF THE WATERS THIS AFTERNOON OR EVENING...AND AGAIN FRIDAY AFTERNOON...EXPECT FOR THE MOST PART JUST A GENERAL RAINFALL. WINDS WILL BE FROM THE NE OR E THROUGH TONIGHT WITH GRADUAL STRENGTHENING. HAVE CAPPED THE WINDS AT 15 KT THROUGH TONIGHT...ALTHOUGH THIS WILL NEED TO BE MONITORED FOR POSSIBLE SCA CONDITIONS. THE SCA NOW GOES INTO EFFECT AT 6 AM FOR THE BAY AND LOWER POTOMAC AND WILL LAST THROUGH FRIDAY INTO FRIDAY NIGHT WITH STRONG EASTERLY WINDS. THE SCA MAY NEED TO BE EXTENDED FURTHER INTO SAT MORNING WITH LOW PRESSURE REMAINING NEAR OUR AREA. EXPECT WINDS TO SUBSIDE BELOW SCA BY SAT AFTERNOON AS LOW PULLS AWAY FROM AREA. SUB-SCA WINDS SUN THROUGH MIDDAY MONDAY UNDER HIGH PRESSURE. NEXT CHANCE FOR SUB-SCA COMES MONDAY AFTERNOON AND TUESDAY AS NEXT SYSTEM APPROACHES OUR AREA. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO 6 AM EDT SATURDAY FOR ANZ531>534-537>543. SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO 2 AM EDT SATURDAY FOR ANZ530. && $$ SYNOPSIS...ADS NEAR TERM...ADS SHORT TERM...MSE LONG TERM...RCM/MSE AVIATION...ADS/MSE MARINE...ADS/MSE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
335 PM EDT THU AUG 6 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 435 AM EDT THU AUG 6 2015 UPPER GREAT LAKES IS WITHIN WESTERLY FLOW ALOFT BETWEEN LARGE UPPER LOW OVER EASTERN CANADA AND UPPER TROUGH OVER FAR WESTERN CANADA. COUPLE OF MAIN SHORTWAVES ARE UPSTREAM OF UPPER GREAT LAKES. THE LEAD WAVE IS OVER SOUTHERN MANITOBA AND IS GENERATING CLUSTER OF SHRA/TSRA SOUTHERN MANITOBA INTO NORTHWEST MINNESOTA. WARM AIR ADVECTION MAINLY IN THE MID LEVELS IS SUPPORTING ARC OF LGT SHRA TOWARD ISLE ROYALE AND NORTHERN LK SUPERIOR. BASED ON HRRR AND RAP AND CURRENT RADAR TRENDS...COULD SEE ISOLD SHR OR SPRINKLES CLIP TIP OF KEWEENAW PENINSULA THIS MORNING. OTHERWISE...MAIN EFFECT FM THIS SHORTWAVE WILL BE A LOT OF MID CLOUDS OVER AT LEAST NORTHERN CWA MOST OF TODAY. SINCE THERE ARE ALREADY A WIDESPREAD AREA OF 5-10KFT BKN CIGS UPSTREAM IN MINNESOTA...BUMPED UP CLOUD COVER TODAY. SOUTHERN CWA SHOULD STAY IN AT LEAST INTERVALS OF SUN AND CLOUDS SO WENT WARMEST THERE WITH MID 70S NEAR WI BORDER. COOLEST READINGS IN THE UPR 60S TO NEAR 70 DEGREES WILL BE CLOSER TO LK SUPERIOR WITH MORE CLOUD COVER AND EAST-SOUTHEAST ONSHORE GRADIENT WINDS. FOR TONIGHT...ATTN TURNS TO SHORTWAVE CURRENTLY OVER WY AND SD. THIS SHORTWAVE MOVES ACROSS NORTHERN PLAINS AND ARRIVES OVER CNTRL MN AND WESTERN WI BY LATE TONIGHT. BULK OF STRONGER Q-VECTOR CONVERGENCE STAYS OUT AHEAD OF THAT SHORTWAVE...BUT AS ASSOCIATED SFC LOW WITH THE WAVE MOVES OVER MN...STRONG MOISTURE ADVECTION AT H85 ALONG WITH ISENTROPIC LIFT 300-305K /H9-H7/ SHOULD SUPPORT INCREASING SHOWERS INTO WESTERN UPR MICHIGAN AFTER MIDNIGHT. POPS RAMP UP TO HIGHER CHANCE AT KIWD AFTER MIDNIGHT WITH SLIGHT CHANCES AS FAR EAST AS ISHPEMING AND IRON MOUNTAIN. MUCAPE IN LOWEST 3KM OR APPROX SFC-H7 STAYS MAINLY SOUTHWEST OF CWA. ISOLD TSRA COULD SNEAK INTO FAR WEST AS MODEST LOW-LEVEL JET MAY COULD ADVECT SMALL PORTION OF INSTABILITY INTO CWA...BUT WILL KEEP TSRA OUT OF CWA THROUGH 12Z FRIDAY. MIN TEMPS MUCH WARMER THAN LAST COUPLE NIGHTS MID 50S TO LOW 60S DUE TO PLENTY OF CLOUD COVER AND STEADY SOUTH WINDS AHEAD OF THE SFC LOW IN MN. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 334 PM EDT THU AUG 6 2015 IN THE MEDIUM/EXTENDED RANGE...SLOW MOVING...FAIRLY STRONG SHRTWV OVER THE NRN ROCKIES/SW CANADA IS FCST TO MOVE SLOWLY TO THE ENE AND INTO FAR NW ONTARIO THIS WEEKEND WHILE UPR TROF OVER QUEBEC IS FCST TO WEAKEN AND MOVE ONLY SLOWLY TO THE E. FCST CHALLENGES WL FOCUS ON TIMING/POPS RELATED TO LARGER SCALE WAA IN ADVANCE OF THE WRN SHRTWV AND OTHER DISTURBANCES TRACKING AHEAD OF IT NEAR THE CNDN BORDER AS WELL AS IMPACT OF PERSISTENT HUDSON BAY HI PRES RDG/DRIER AIR HELD NEARLY IN PLACE UNDER CONFLUENT FLOW ALOFT ON THE WRN FLANK OF SLOW MOVING QUEBEC TROF. UNFORTUNATELY...SHARP MODEL DIFFERENCES ARE APRNT AS EARLY AS FRI NGT ON THE MSLP/PCPN EVOLUTION. SO CONFIDENCE REMAINS LO ON THE FCST THRU THE WEEKEND. FRI NGT...SHRTWV STREAKING THRU THE UPR MIDWEST WELL IN ADVANCE OF STRONGER DISTURBANCE MOVING NEAR THE CNDN BORDER IS FCST BY MANY MODELS...ESPECIALLY THE 12Z GFS...TO SHEAR OUT AND SLIDE SE THRU WI ON WRN FLANK OF HUDSON BAY HI PRES RDG. ALTHOUGH THE 12Z NAM ALSO SHOWS THE DIGGING SHRTWV AS WELL...THAT MODEL INDICATES BAND OF MODEST WAA/ ISENTROPIC ASCENT BEST DEPICTED ON THE 305-310K SFCS /ABOUT H775-675/ BTWN STRONGER DISTURBANCE AND HUDSON BAY HI PRES RDG AND SOME UPR DVGC IN LEFT EXIT OF 80-90KT H3 JET MAX WL ALLOW A BAND OF SHOWERS TO DRIFT E ACROSS UPR MI. WHEREAS THE NAM DROPS 0.50 TO 1.00 INCH OF RA OVER MUCH OF THE NRN CWA...THE GFS QPF IS NEAR ZERO AS HUDSON BAY HI PRES BUILDS BACK INTO THE CWA ON FRI EVNG. SINCE THE BULK OF THE OTHER MODELS APPEAR TO SUPPORT THE NAM AND THE 12Z GFS IS VERY DIFFERENT FM THE 06Z RUN /WHICH LOOKED A LOT LIKE THE 12Z NAM FOR QPF/...WL FOLLOW A FCST CLOSER TO THAT MODEL. AS BAND OF STRONGEST WAA SHIFTS TO THE E THRU THE NGT AND LARGER SCALE QVECTOR DVGC/ SUBSIDENCE MOVE IN OVERNGT...EXPECT THE HIER POPS TO DIMINISH W-E. SAT...AFTER ANY LINGERING SHOWERS END OVER THE E EARLY IN THE DAY... RISING HGTS/DEEP LYR QVECTOR DVGC/SUBSIDENCE/MORE LLVL ACYC FLOW OVER THE UPR LKS WELL TO THE S OF SHRTWV LIFTING SLOWLY TO THE NE THRU FAR NW ONTARIO SHOULD BRING GENERALLY DRY WX TO THE CWA. COMBINATION OF AT LEAST PARTIAL SUNSHINE AND H85 TEMPS RISING AS HI AS 16C OVER THE W LATE IN THE DAY WL SUPPORT MAX TEMPS REACHING AOA 80 ACRS THE W HALF OF THE CWA. MORE LINGERING CLDS AND LOWER H85 TEMPS OVER THE E WL HOLD TEMPS THERE IN THE 70S. SOME OF THE MODELS INDICATE SOME SHOWERS/TS IN ADVANCE OF COLD FNT ATTENDANT TO ONTARIO SHRTWV/SFC LO MAY REACH THE W LATE IN THE DAY...BUT WL FCST NO HIER THAN LO CHC POPS TO ACCOUNT FOR MODEL TIMING DIFFERENCES/DRIER GUIDANCE WITH MORE PERSISTENT HUDSON BAY HI PRES RDG. SAT NGT THRU MON...SHRTWV IN FAR NW ONTARIO IS PROGGED TO SLIDE SLOWLY TO THE ESE THRU NRN ONTARIO TO THE E OF BLDG UPR RDG IN THE PLAINS. ALTHOUGH THERE IS GENERAL AGREEMENT THE COLD FNT ATTENDANT TO THIS DISTURBANCE AS WELL AS A TRAILING LO PRES TROF WL DROP SE THRU THE UPR LKS...TIMING DIFFERENCES ARE APRNT AMONG THE GUIDANCE AS DISAGREEMENT ON THE PERSISTENCE OF HUDSON BAY HI PRES RDG/AXIS OF DRIER AIR REMAIN. WITH LO CONFIDENCE...WL THUS HOLD NEAR THE CONSENSUS FCST. TEMPS IN ADVANCE OF THE COLD FNT WL RUN AOA NORMAL WITH H85 TEMPS WITHIN A FEW DEGREES OF 14C. EXTENDED...AS UPR RDG IN THE PLAINS AMPLIFIES NEXT WEEK AND AN UPR TROF DEEPENS IN SE CANADA/THE ERN CONSU...THE FLOW ALOFT WL TURN TO THE NNW OVER THE GREAT LKS. CNDN HI PRES SHOULD BRING PREDOMINATELY DRIER...COOLER WX TO THE CWA FOR TUE INTO THU. A SHRTWV RIDING OVER THE PLAINS RDG DIGGING SEWD THRU THE NW FLOW ALF TOWARD THE UPR LKS MAY BRING SOME SHOWERS LATE IN THE DAY NEXT THU...BUT CONFIDENCE THIS FAR OUT ON THE TIMING OF THIS DISTURBANCE IS TOO LO TO VARY FM CONSENSUS LO CHC POPS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 231 PM EDT THU AUG 6 2015 LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE TONIGHT. COULD SEE SHOWERS TOWARD DAYBREAK AT KIWD...BUT WEATHER SHOULD STAY MAINLY DRY AT KCMX AND KSAW UNTIL 14-17Z. CEILING MAY NEAR MVFR BY 18Z FRIDAY AT IWD. OTHERWISE...WINDS SHOULD REMAIN AROUND 10KTS OR LESS THROUGH THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 334 PM EDT THU AUG 6 2015 A COUPLE OF WEAK LO PRES TROFS WILL MOVE ACROSS THE UPPER GREAT LAKES REGION INTO EARLY NEXT WEEK...BUT RELATIVELY FLAT PRES GRADIENT WILL MAINTAIN WINDS UNDER 20KTS THRU THE PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...KC AVIATION...KF MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
234 PM EDT THU AUG 6 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 435 AM EDT THU AUG 6 2015 UPPER GREAT LAKES IS WITHIN WESTERLY FLOW ALOFT BETWEEN LARGE UPPER LOW OVER EASTERN CANADA AND UPPER TROUGH OVER FAR WESTERN CANADA. COUPLE OF MAIN SHORTWAVES ARE UPSTREAM OF UPPER GREAT LAKES. THE LEAD WAVE IS OVER SOUTHERN MANITOBA AND IS GENERATING CLUSTER OF SHRA/TSRA SOUTHERN MANITOBA INTO NORTHWEST MINNESOTA. WARM AIR ADVECTION MAINLY IN THE MID LEVELS IS SUPPORTING ARC OF LGT SHRA TOWARD ISLE ROYALE AND NORTHERN LK SUPERIOR. BASED ON HRRR AND RAP AND CURRENT RADAR TRENDS...COULD SEE ISOLD SHR OR SPRINKLES CLIP TIP OF KEWEENAW PENINSULA THIS MORNING. OTHERWISE...MAIN EFFECT FM THIS SHORTWAVE WILL BE A LOT OF MID CLOUDS OVER AT LEAST NORTHERN CWA MOST OF TODAY. SINCE THERE ARE ALREADY A WIDESPREAD AREA OF 5-10KFT BKN CIGS UPSTREAM IN MINNESOTA...BUMPED UP CLOUD COVER TODAY. SOUTHERN CWA SHOULD STAY IN AT LEAST INTERVALS OF SUN AND CLOUDS SO WENT WARMEST THERE WITH MID 70S NEAR WI BORDER. COOLEST READINGS IN THE UPR 60S TO NEAR 70 DEGREES WILL BE CLOSER TO LK SUPERIOR WITH MORE CLOUD COVER AND EAST-SOUTHEAST ONSHORE GRADIENT WINDS. FOR TONIGHT...ATTN TURNS TO SHORTWAVE CURRENTLY OVER WY AND SD. THIS SHORTWAVE MOVES ACROSS NORTHERN PLAINS AND ARRIVES OVER CNTRL MN AND WESTERN WI BY LATE TONIGHT. BULK OF STRONGER Q-VECTOR CONVERGENCE STAYS OUT AHEAD OF THAT SHORTWAVE...BUT AS ASSOCIATED SFC LOW WITH THE WAVE MOVES OVER MN...STRONG MOISTURE ADVECTION AT H85 ALONG WITH ISENTROPIC LIFT 300-305K /H9-H7/ SHOULD SUPPORT INCREASING SHOWERS INTO WESTERN UPR MICHIGAN AFTER MIDNIGHT. POPS RAMP UP TO HIGHER CHANCE AT KIWD AFTER MIDNIGHT WITH SLIGHT CHANCES AS FAR EAST AS ISHPEMING AND IRON MOUNTAIN. MUCAPE IN LOWEST 3KM OR APPROX SFC-H7 STAYS MAINLY SOUTHWEST OF CWA. ISOLD TSRA COULD SNEAK INTO FAR WEST AS MODEST LOW-LEVEL JET MAY COULD ADVECT SMALL PORTION OF INSTABILITY INTO CWA...BUT WILL KEEP TSRA OUT OF CWA THROUGH 12Z FRIDAY. MIN TEMPS MUCH WARMER THAN LAST COUPLE NIGHTS MID 50S TO LOW 60S DUE TO PLENTY OF CLOUD COVER AND STEADY SOUTH WINDS AHEAD OF THE SFC LOW IN MN. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 347 AM EDT THU AUG 6 2015 NAM SHOWS A SHORTWAVE OVER THE NORTHERN PLAINS 12Z FRI WITH ANOTHER ENTERING INTO THE UPPER GREAT LAKES THEN. THIS SHORTWAVE MOVES THROUGH ON FRI AND THE OTHER SHORTWAVE MOVES SLOWLY EAST AND AFFECTS THE AREA ON SAT. NAM SHOWS SOME 850-500 MB Q-VECTOR CONVERGENCE AND MOISTURE MOVING THROUGH ON FRI AND BOTH MOVE OUT SAT AFTERNOON BEFORE RETURNING SAT NIGHT. CONFIDENCE IS LOW WITH THIS FORECAST AS GFS...ECMWF AND NAM ALL HAVE DIFFERENT IDEAS FOR HOW THIS WEATHER SCENARIO IS GOING TO PLAY OUT. ECMWF IS DRIER AND FURTHER SOUTH WITH IT PCPN. GFS IS QUICKER MOVING PCPN THROUGH. WENT WITH A BLEND OF THE SOLUTIONS WHICH SEEMED TO KEEP SOME CONTINUITY TO THE FORECAST. LOOKS LIKE THERE WILL BE A BREAK IN PCPN FOR LATE FRI NIGHT INTO SAT MORNING AND THEN ANOTHER WAVE COMES IN AND TRIED TO REFLECT THIS IN THE FORECAST WITH A BREAK IN THE PCPN. BEST CHANCE FOR PCPN APPEARS TO BE FRI INTO FRI EVENING...THEN HAVE LOW CHANCE POPS AND LOW CONFIDENCE FOR SAT AND SAT NIGHT. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES. IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE OVER THE SOUTHERN AND CENTRAL PLAINS 12Z SUN WITH A TROUGH ACROSS CENTRAL CANADA AND A SHORTWAVE IN THE NORTHERN PLAINS. THIS SHORTWAVE HEADS EAST INTO THE UPPER GREAT LAKES SUN NIGHT INTO MON. THIS SHORTWAVE HEADS OVER THE TOP OF THE RIDGE ON MON AND PUSHES IT BACK INTO THE NORTHERN ROCKIES. THE UPPER FLOW BECOMES MORE AMPLIFIED ON TUE WITH THE RIDGE BUILDING INTO THE CANADIAN ROCKIES AND THE TROUGH DIGGING INTO THE ERN U.S. THE RIDGE BUILDS INTO THE NORTHERN PLAINS 12Z WED. SFC RIDGING MOVES INTO THE UPPER GREAT LAKES TUE AND REMAINS INTO WED. TEMPERATURES WILL CONTINUE TO BE SLIGHTLY BELOW NORMAL FOR THIS FORECAST PERIOD. AS THE SFC HIGH BUILDS IN FOR MONDAY...WENT DRY FOR MON NIGHT THROUGH WED AND REMOVED POPS FOR THAT TIME PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 231 PM EDT THU AUG 6 2015 LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE TONIGHT. COULD SEE SHOWERS TOWARD DAYBREAK AT KIWD...BUT WEATHER SHOULD STAY MAINLY DRY AT KCMX AND KSAW UNTIL 14-17Z. CEILING MAY NEAR MVFR BY 18Z FRIDAY AT IWD. OTHERWISE...WINDS SHOULD REMAIN AROUND 10KTS OR LESS THROUGH THE PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 435 AM EDT THU AUG 6 2015 A COUPLE OF WEAK TROUGHS OR LOW PRESSURE SYSTEMS WILL MOVE THROUGH THE UPPER GREAT LAKES REGION THROUGH THIS WEEKEND...BUT WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...07 AVIATION...KF MARINE...SRF
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1228 PM CDT THU AUG 6 2015 .UPDATE... ISSUED AT 1230 PM CDT THU AUG 6 2015 SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUED TO SPREAD EAST/SOUTHEAST OVER THE AREA EARLY THIS AFTERNOON. BELIEVE THIS WILL WEAKEN THE NEXT SEVERAL HOURS. RECENT HRRR MODEL RUNS SEEMREASONABLE IN DEVELOPING NEW CONVECTION ACROSS PARTS OF SERN SD AND NERN NE IN THE LATE AFTERNOON/EVENING. THERE APPEARS TO BE SOME RISK OVER SEVERE STORMS IN THOSE AREAS. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 357 AM CDT THU AUG 6 2015 AN ANALYSIS OF THE 850MB 00Z CHART DEPICTED A RIDGE OF HIGH PRESSURE OFF TO OUR EAST...WITH A DEVELOPING AREA OF LOW PRESSURE OVER WYOMING. RELATIVELY WEAK FLOW WAS IN PLACE HOWEVER PLENTY OF DEEP LOW LEVEL MOISTURE WAS SURGING INTO THE CENTRAL PLAINS. THE 500 MB CHART ALSO DEPICTED A RIDGE OF HIGH PRESSURE OVER THE NATIONS MID SECTION...AS WELL AS AN AREA OF HEIGHT FALLS AROUND A DEEPENING TROUGH NEAR THE PACIFIC NORTHWEST. A SURFACE COLD FRONT ASSOCIATED WITH THE 850 MB LOW WILL BRING SHOWERS AND THUNDERSTORMS TO THE AREA LATER TODAY AND INTO TONIGHT. AROUND 3000 J/KG OF MAX CAPE WILL BE PRESENT ACROSS THE NORTHERN HALF OF THE CWA WITH LAPSE RATES AROUND 7 C/KM. 40 KTS OF BULK SHEAR WILL ALSO BE PRESENT AND NORMAL TO THE SURFACE BOUNDARY...PROVIDING AN OPPORTUNITY FOR DISCRETE SUPERCELL DEVELOPMENT. THEREFORE THE NORTHERN HALF OF THE CWA HAS BEEN PLACED IN A SLIGHT RISK FOR SEVERE STORMS...WITH THE REST OF THE AREA IN A MARGINAL RISK. EXPECT LARGE HAIL AND STRONG WINDS WILL BE THE MAIN THREATS IF STORMS DEVELOP...HOWEVER THE CHANCE FOR AN ISOLATED TORNADO OR TWO CANNOT BE ENTIRELY RULED OUT. DRY CONDITIONS ARE EXPECTED ON FRIDAY BEFORE ANOTHER SHORTWAVE SWINGS THROUGH THE REGION PRODUCING SHOWERS AND THUNDERSTORMS FRIDAY NIGHT INTO SATURDAY AS AN MCS PROPAGATES ACROSS THE STATE. TEMPERATURES TODAY WILL REMAIN FAIRLY PLEASANT IN THE LOW TO MID 80S. ALTHOUGH WARMER AIR WILL ADVECT IN ON FRIDAY WITH HIGHS CLOSER TO 90 DEGREES. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 357 AM CDT THU AUG 6 2015 SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE AS THE RESULT OF WEAK DISTURBANCES THROUGH THE WEEKEND. HOWEVER HIGH PRESSURE IS STILL PROGGED TO BUILD INTO THE COUNTRIES MID SECTION EARLY NEXT WEEK. POTENTIALLY PROVIDING US WITH A PERIOD OF DRIER WEATHER AND HIGHS IN THE LOW 80S MONDAY THROUGH WEDNESDAY. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1230 PM CDT THU AUG 6 2015 MAINLY VFR CONDITIONS EXPECTED...BUT COULD HAVE MVFR VSBYS AND POSSIBLY MVFR CIGS WITH PCPN INTO MID AFTERNOON AT KOMA AND KLNK. STORMS COULD AFFECT KOFK LATER THIS AFTN BUT CONFIDENCE NOT HIGH ENOUGH TO PUT IN A TEMPO GROUP AT THIS TIME. ACTIVITY WOULD LIKELY BE ISOLD AND WILL WATCH AND AMEND IF NEEDED. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...MILLER SHORT TERM...KG LONG TERM...KG AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
205 PM PDT THU AUG 6 2015 .SYNOPSIS...MONSOON MOISTURE CREEPING INTO THE AREA WILL BRING INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE REGION TODAY. THUNDERSTORM ACTIVITY WILL DECREASE RAPIDLY FROM WEST TO EAST FRIDAY AS DRIER AIR PUSHES INTO THE REGION FOR THE WEEKEND. ANOTHER ROUND OF MOISTURE MAY BE ON TAP FOR THE MIDDLE OF NEXT WEEK. && .SHORT TERM...TODAY THROUGH FRIDAY NIGHT. CONVECTION THUS FAR THIS AFTERNOON HAS BEEN CONFINED TO MAINLY WESTERN SAN BERNARDINO COUNTY WHERE SOME MID LEVEL INSTABILITY IS FUELING FAST MOVING STORMS ALONG THE LEADING EDGE OF A STRONG UPPER LEVEL JET. SUBCLOUD LAYERS IN THIS AREA ARE QUITE DRY WITH SURFACE DEWPOINTS MAINLY IN THE 30S...SO GUSTY DOWNBURST WINDS ARE A CONCERN BUT STORMS WILL STRUGGLE TO PRODUCE ANY MEASURABLE RAINFALL. WHILE THE STORMS HAVE STRUGGLED TO DEPOSIT RAINFALL....THEY HAVE BEEN VERY EFFICIENT LIGHTNING PRODUCERS WITH OVER 250 CLOUD TO GROUND LIGHTNING STRIKES SINCE THE NOON HOUR IN WESTERN SAN BERNARDINO COUNTY. WITH THIS ACTIVITY MOVING NORTHWARD...A RED FLAG WARNING HAS BEEN POSTED FOR DRY LIGHTNING FOR MUCH OF SAN BERNARDINO COUNTY AND THE EASTERN HALF OF INYO COUNTY THROUGH LATE TONIGHT. STILL EXPECTING ATTENTION TO SHIFT FURTHER EAST THIS AFTERNOON AS MORE ROBUST CONVECTION DEVELOPS ACROSS THE LOWER COLORADO RIVER VALLEY. CURRENT MESOANALYSIS SHOWS SURFACE BASED INSTABILITY BUILDING ACROSS THIS AREA WITH CAPE VALUES EXCEEDING 1000 J/KG WITH LIMITED CAPPING. SEVERAL CONSECUTIVE HRRR RUNS HAVE INSISTED ON BREAKING THIS AREA OUT IN THE NEXT FEW HOURS. THE POTENTIAL FOR STRONG AND POTENTIALLY DAMAGING DOWNBURST WINDS IS QUITE HIGH ALONG THE COLORADO RIVER ROUGHLY FROM BULLHEAD CITY SOUTHWARD TO LAKE HAVASU...SO THIS AREA WILL BE WATCHED CLOSELY FOR THE POSSIBILITY OF SEVERE STORMS. TONIGHT...ACTIVITY ACROSS MOHAVE AND EASTERN SAN BERNARDINO COUNTIES WILL DRIFT NORTHWARD INTO SOUTHERN NEVADA WHILE ADDITIONAL ACTIVITY IS LIKELY TO BREAK OUT ACROSS OUR SOUTHERN GREAT BASIN ZONES. WITH INCREASING SOUTHWESTERLY SHEAR AS A PACIFIC TROUGH APPROACHES...A FEW BANDS OF PERSISTENT CONVECTION MAY DEVELOP OVERNIGHT WHICH WILL BE OUR PRIMARY CONCERN FOR ANY FLASH FLOODING. INDIVIDUAL STORM MOTION WILL BE RATHER SWIFT...BUT TRAINING STORMS WILL POSE A FLOOD RISK WITH THE HIGH PRECIPITABLE WATER IN PLACE...SO MAINTAINED THE FLASH FLOOD WATCH TO ACCOUNT FOR THIS FOR MOHAVE AND LINCOLN COUNTIES. STRONG AND POTENTIALLY DAMAGING WINDS WILL REMAIN POSSIBLE OVERNIGHT DUE TO STRENGTHENING DEEP LAYER WIND SHEAR AS WELL AS THE POSSIBILITY OF HAIL WITH THE STRONGER STORMS. FRIDAY...PACIFIC TROUGH WILL SWEEP EASTWARD ON FRIDAY DRAGGING THE DEEPER MOISTURE AND INSTABILITY WITH IT. ANTICIPATE ONGOING CONVECTION AND CLOUD COVER TO BE CONFINED MAINLY TO SOUTHERN NEVADA AND NORTHWEST ARIZONA IN THE MORNING WHILE SHIFTING EASTWARD THROUGH THE DAY. BY 5 PM...ANY REMAINING THUNDERSTORM ACTIVITY WILL BE PRIMARILY CONFINED TO EASTERN MOHAVE COUNTY AND FAR EASTERN AND NORTHERN LINCOLN COUNTIES. FLASH FLOODING WILL REMAIN A CONCERN WITH TRAINING STORMS...BUT THE THREAT WILL BE TRANSLATING EASTWARD THROUGH THE DAY. WITH STRONG SHEAR IN PLACE...SEVERE STORMS WILL BE A POSSIBILITY AS WELL DEPENDING ON THE DEGREE OF CLOUD COVER AND HOW MUCH IT INHIBITS DAYTIME HEATING. BY FRIDAY EVENING MOSTLY DRY AND CLEAR CONDITIONS WILL OVERSPREAD THE ENTIRE REGION. .LONG TERM...SATURDAY THROUGH THURSDAY. A DRY SOUTHWEST FLOW WILL BE OVER THE ENTIRE FORECAST AREA SATURDAY THROUGH MONDAY. HIGH PRESSURE OVER TEXAS WILL EXPAND WEST TOWARD NEW MEXICO WHILE A TROUGH OF LOW PRESSURE STRETCHES GENERALLY NORTH- SOUTH ALONG THE WEST COAST STARTING LATE MONDAY. THIS COMBINATION WILL ALLOW SOUTHERLY FLOW TO DEVELOP WITH MOISTURE TRACKING NORTHWARD MAINLY INTO MOHAVE COUNTY. WILL CONTINUE THE SHOWER AND THUNDERSTORM CHANCES FOR THIS AREA TUESDAY. SOUTHERLY FLOW APPEARS TO STICK AROUND THROUGH THURSDAY, WITH MOISTURE SLIGHTLY EDGING WEST WEDNESDAY AND PERHAPS LINGERING INTO THURSDAY. THERE REMAINS UNCERTAINTY IN JUST HOW MUCH MOISTURE WILL ARRIVE AND HOW FAR WEST IT MAY TRACK. OTHERWISE NEAR NORMAL TEMPS ARE EXPECTED THROUGHOUT THE LONG-TERM PERIOD. BREEZY SOUTH TO SOUTHWEST WINDS WILL BE COMMON EACH AFTERNOON AND EARLY EVENING. && .FIRE WEATHER...THUNDERSTORMS HAVE DEVELOPED ACROSS NORTHWESTERN SAN BERNARDINO AND SOUTHERN INYO COUNTY, HOWEVER, WITH DRY LOW-LEVELS, VERY LITTLE PRECIPITATION WAS REACHING THE GROUND AND AREA RADARS SHOWED WEAK TO NO RETURNS ON THE LOWEST ELEVATION SCANS. THUS, THIS HAS CREATED A SIGNIFICANT POTENTIAL FOR DRY LIGHTNING IN NORTHWEST SAN BERNARDINO COUNTY AND DEATH VALLEY NATIONAL PARK THIS AFTERNOON INTO TONIGHT. A RED FLAG WARNING WAS ISSUED FOR DRY LIGHTNING FOR CALIFORNIA ZONES 227 AND 228 AS A RESULT. WE WILL NEED TO KEEP AN EYE ON THE REST OF INYO, ESMERALDA, SOUTHERN AND CENTRAL NYE AS WELL AS WESTERN CLARK AS A SMALL RISK FOR DRY LIGHTNING ALSO EXISTS IN THESE AREAS THROUGH TONIGHT, HOWEVER, CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE ANY HEADLINES. HOWEVER, BASED ON THE GENERAL TRENDS THE THREAT INTO ESMERALDA AND NORTHWESTERN INYO COUNTY LOOKS VERY LOW AND THAT MOST ACTIVITY THERE SHOULD BE JUST SHOWERS. ACROSS MOHAVE, LINCOLN AND MOST OF CLARK COUNTIES STORMS ARE EXPECTED TO GENERALLY BE WET IN NATURE DUE TO THE HIGH MOISTURE CONTENT OF THE ATMOSPHERE. AS DRIER AIR SWEEPS IN FROM THE SOUTHWEST THURSDAY NIGHT INTO FRIDAY, THIS WILL HELP TO END THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS FROM WEST TO EAST. HOWEVER, THIS WILL ALSO HELP TO INCREASE WINDS FROM THE SOUTH TO SOUTHWEST. RELATIVE HUMIDITY VALUES AT OR BELOW 15 PERCENT, WIND GUSTS OF 35 MPH OR GREATER AS WELL AS FUELS BEING DRIED OUT ENOUGH LOOK TO BE MET IN NEVADA ZONE 462 AND THE FIRE WEATHER WATCH WAS UPGRADED TO A RED FLAG WARNING HERE. ELSEWHERE, ONLY ONE OR TWO OF THESE CRITERIA LOOK TO BE MET SO NO HEADLINES WERE ISSUED. && .AVIATION...FOR MCCARRAN...SOUTH TO SOUTHWEST WINDS IN THE 9-12KT RANGE WITH GUSTS TO 20KTS EXPECTED THROUGH THE EVENING. SHOWERS AND THUNDERSTORMS EXPECTED TO BREAK OUT SOMETIME BETWEEN 01Z-05Z AND CONTINUING MUCH OF NIGHT. BIGGEST CONCERN WILL BE GUSTY AND ERRATIC OUTFLOW WINDS...WHICH COULD EXCEED 35KTS IF ANY ROBUST STORMS DEVELOP IN THE VALLEY. OTHERWISE...CIGS IN THE 9-12K RANGE WITH DISRUPTIONS TO APPROACH CORRIDORS LIKELY AT TIMES. SHOWERS AND THUNDERSTORMS REMAIN POSSIBLE THROUGH 21Z FRIDAY BEFORE IMPROVING CONDITIONS MOVE IN WITH DECREASING CLOUD COVER. SOUTHWEST WINDS OF 10-15KTS WITH GUSTS TO 25KTS EXPECTED FRIDAY AFTERNOON. FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...ISOLATED TO SCATTERED SHRA/TSRA POSSIBLE BEFORE 00Z...PRIMARILY SOUTH OF THE INTERSTATE 15 CORRIDOR. PRECIPITATION CHANCES WILL SPREAD NORTH INTO THE SOUTHERN GREAT BASIN THIS EVENING...THEN END RAPIDLY FROM WEST TO EAST THROUGH THE DAY FRIDAY. STORMS WILL HAVE THE POTENTIAL TO PRODUCE ERRATIC WIND GUSTS IN EXCESS OF 45 KTS. CIGS ARE GENERALLY EXPECTED TO REMAIN AOA 10K FEET EXCEPT NEAR SHRA/TSRA WHERE THEY COULD LOWER TO 6-8K FEET. GUSTY WINDS OF 15-20KTS WITH GUSTS TO 30KTS EXPECTED FRIDAY AFTERNOON ACROSS THE WESTERN MOJAVE DESERT AND SOUTHERN GREAT BASIN. && .SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. && $$ SHORT TERM/AVIATION...OUTLER LONG TERM.............PADDOCK FIRE WEATHER...STACHELSKI FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE: HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
534 PM CDT THU AUG 6 2015 .UPDATE... ISSUED AT 534 PM CDT THU AUG 6 2015 CANCELED THE FLASH FLOOD WATCH FOR ALL BUT THE JAMES RIVER VALLEY. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 250 PM CDT THU AUG 6 2015 HEAVY RAINFALL POTENTIAL THROUGH EARLY THIS EVENING SOUTH CENTRAL AND INTO THE JAMES RIVER VALLEY HIGHLIGHTS THE SHORT TERM FORECAST. THE FLASH FLOOD WATCH FOR THE SOUTH CENTRAL AND JAMES RIVER VALLEY REMAINS IN EFFECT UNTIL 10 PM CDT THIS EVENING. RADAR TRENDS THROUGH 20 UTC DEPICT NUMEROUS SLOWING MOVING...WARM RAIN PROCESS DOMINATED STORMS ACROSS THE AFOREMENTIONED AREAS. GIVEN TRENDS IN THE 17-19 UTC HRRR ITERATIONS WHICH HAVE OVERALL HANDLED THE EVENT WELL...EXPECT ACTIVITY TO BEGIN TO WANE/PROPAGATE EAST INTO THE RED RIVER VALLEY BY 23-00 UTC. FURTHER WEST NEAR THE OCCLUDED FRONTAL BOUNDARY FROM NORTHEAST MONTANA THROUGH LAKE OAHE...DIURNALLY DRIVEN ISOLATED CONVECTION IS EXPECTED. HOWEVER...SEVERE WEATHER IS NOT ANTICIPATED. GIVEN GOOD AGREEMENT ON THE 12 UTC DETERMINISTIC SUITE...A DRY COLD FRONTAL PASSAGE IS EXPECTED ON FRIDAY...WITH SEASONABLE TEMPERATURES AND MOSTLY SUNNY SKIES. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 250 PM CDT THU AUG 6 2015 A POTENTIAL WARM UP NEXT WEEK HIGHLIGHTS THE EXTENDED FORECAST. THE 12 UTC GUIDANCE SUITE IS IN AGREEMENT ON QUASI-ZONAL THIS WEEKEND AMPLIFYING EARLY NEXT WEEK AS AN INTERMOUNTAIN WEST/CENTRAL CONUS UPPER LEVEL RIDGE BUILDS. THIS SUPPORTS A POSSIBLE TRANSITION FROM NEAR NORMAL TEMPERATURES THIS WEEKEND...WARMING THROUGH NEXT WEEK. GIVEN WEAK WAVES EMBEDDED IN THE FAST QUASI-ZONAL FLOW THIS WEEKEND...DAILY CHANCES FOR THUNDERSTORMS ARE FORECAST SATURDAY AND SUNDAY GENERALLY SOUTH OF ND HIGHWAY 200. SEVERE THUNDERSTORMS ARE NOT EXPECTED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 250 PM CDT THU AUG 6 2015 THUNDERSTORMS ARE LIKELY TO IMPACT KJMS THIS AFTERNOON INTO THE EARLY EVENING WITH IFR CONDITIONS POSSIBLE. VFR CONDITIONS ARE FORECAST ELSEWHERE WITH ONLY ISOLATED SHOWERS AND THUNDERSTORMS ACROSS NORTHWEST AND CENTRAL NORTH DAKOTA THAT WILL FADE WITH SUNSET. VFR CONDITIONS ARE FORECAST FRIDAY AS A DRY COLD FRONT MOVES THROUGH THE AREA. NORTHWEST WIND GUSTS TO 25 KTS ARE POSSIBLE AT KISN AND KMOT FRIDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 10 PM CDT THIS EVENING FOR NDZ025-037- 048-051. && $$ UPDATE...WAA SHORT TERM...AYD LONG TERM...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
316 PM CDT THU AUG 6 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 250 PM CDT THU AUG 6 2015 HEAVY RAINFALL POTENTIAL THROUGH EARLY THIS EVENING SOUTH CENTRAL AND INTO THE JAMES RIVER VALLEY HIGHLIGHTS THE SHORT TERM FORECAST. THE FLASH FLOOD WATCH FOR THE SOUTH CENTRAL AND JAMES RIVER VALLEY REMAINS IN EFFECT UNTIL 10 PM CDT THIS EVENING. RADAR TRENDS THROUGH 20 UTC DEPICT NUMEROUS SLOWING MOVING...WARM RAIN PROCESS DOMINATED STORMS ACROSS THE AFOREMENTIONED AREAS. GIVEN TRENDS IN THE 17-19 UTC HRRR ITERATIONS WHICH HAVE OVERALL HANDLED THE EVENT WELL...EXPECT ACTIVITY TO BEGIN TO WANE/PROPAGATE EAST INTO THE RED RIVER VALLEY BY 23-00 UTC. FURTHER WEST NEAR THE OCCLUDED FRONTAL BOUNDARY FROM NORTHEAST MONTANA THROUGH LAKE OAHE...DIURNALLY DRIVEN ISOLATED CONVECTION IS EXPECTED. HOWEVER...SEVERE WEATHER IS NOT ANTICIPATED. GIVEN GOOD AGREEMENT ON THE 12 UTC DETERMINISTIC SUITE...A DRY COLD FRONTAL PASSAGE IS EXPECTED ON FRIDAY...WITH SEASONABLE TEMPERATURES AND MOSTLY SUNNY SKIES. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 250 PM CDT THU AUG 6 2015 A POTENTIAL WARM UP NEXT WEEK HIGHLIGHTS THE EXTENDED FORECAST. THE 12 UTC GUIDANCE SUITE IS IN AGREEMENT ON QUASI-ZONAL THIS WEEKEND AMPLIFYING EARLY NEXT WEEK AS AN INTERMOUNTAIN WEST/CENTRAL CONUS UPPER LEVEL RIDGE BUILDS. THIS SUPPORTS A POSSIBLE TRANSITION FROM NEAR NORMAL TEMPERATURES THIS WEEKEND...WARMING THROUGH NEXT WEEK. GIVEN WEAK WAVES EMBEDDED IN THE FAST QUASI-ZONAL FLOW THIS WEEKEND...DAILY CHANCES FOR THUNDERSTORMS ARE FORECAST SATURDAY AND SUNDAY GENERALLY SOUTH OF ND HIGHWAY 200. SEVERE THUNDERSTORMS ARE NOT EXPECTED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 250 PM CDT THU AUG 6 2015 THUNDERSTORMS ARE LIKELY TO IMPACT KJMS THIS AFTERNOON INTO THE EARLY EVENING WITH IFR CONDITIONS POSSIBLE. VFR CONDITIONS ARE FORECAST ELSEWHERE WITH ONLY ISOLATED SHOWERS AND THUNDERSTORMS ACROSS NORTHWEST AND CENTRAL NORTH DAKOTA THAT WILL FADE WITH SUNSET. VFR CONDITIONS ARE FORECAST FRIDAY AS A DRY COLD FRONT MOVES THROUGH THE AREA. NORTHWEST WIND GUSTS TO 25 KTS ARE POSSIBLE AT KISN AND KMOT FRIDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 10 PM CDT THIS EVENING FOR NDZ022-023- 025-035>037-046>048-050-051. && $$ SHORT TERM...AYD LONG TERM...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1223 PM CDT THU AUG 6 2015 .UPDATE... ISSUED AT 1219 PM CDT THU AUG 6 2015 QUICK UPDATE TO CANCEL THE FLASH FLOOD WATCH WEST OF THE MISSOURI RIVER AS MORNING CONVECTION AND TEMPERATURES IN THE 60S HAVE DIMINISHED THE CHANCES FOR DEEP CONVECTION AND ASSOCIATED POTENTIAL FLASH FLOODING. OTHERWISE...CONVECTIVE COVERAGE AND INTENSITY CONTINUES TO SLOWLY INCREASE EAST OF THE MISSOURI RIVER AND SOUTH OF NORTH DAKOTA HIGHWAY 200...AND THE WATCH REMAINS IN EFFECT FOR THESE AREAS. UPDATE ISSUED AT 1059 AM CDT THU AUG 6 2015 NO SIGNIFICANT CHANGES AT THIS TIME TO THE ONGOING FORECAST. THE QUESTION FOR THE AFTERNOON IS HOW MUCH INSTABILITY AND RESULT STORM COVERAGE AND INTENSITY CAN BE REALIZED GIVEN CURRENT CLOUD COVER ACROSS SOUTH CENTRAL NORTH DAKOTA AND INTO THE JAMES RIVER VALLEY. GIVEN RADAR TRENDS THROUGH 16 UTC...MAY BE ABLE TO TRIM A FEW COUNTIES OFF OF THE WESTERN PORTION OF THE FLASH FLOOD WATCH WHERE ONGOING WEAKER CONVECTION WILL PREVENT INSTABILITY BUILD UP NEEDED FOR DEEPER CONVECTION AND A FLASH FLOOD THREAT. THE 12-14 UTC HRRR ITERATIONS AND 12 UTC GLOBAL SUITE STILL SUGGEST STORM COVERAGE AND INTENSITY INCREASING THROUGH THE AFTERNOON SOUTH CENTRAL AND INTO SOUTHEAST NORTH DAKOTA. AS STATED ABOVE...CLOUD COVER DOES ADD UNCERTAINTY TO THIS SOLUTION...HOWEVER...THE STRONG SHORTWAVE STILL REMAINS TO THE WEST OF THESE AREAS WHICH MAY PROVIDE ENOUGH FORCING TO OVERCOME THIS ISSUE. UPDATE ISSUED AT 832 AM CDT THU AUG 6 2015 SHOWERS/STORMS CONTINUE TO LIFT TO THE NORTHEAST VERY SLOWLY...WITH SOME AREAS OF PRECIPITATION REMAINING NEARLY STATIONARY OVER PORTIONS OF THE SOUTHERN JAMES RIVER VALLEY. LATEST HIGH REST GUIDANCE CONTINUES TO INDICATE SLOW STORM MOTION THROUGH THE REST OF THE DAY...THEREFORE THE FLOODING THREAT WILL CONTINUE...PARTICULARLY OVER SOUTH CENTRAL INTO THE JAMES RIVER VALLEY WHERE CURRENT FLASH FLOOD WATCH REMAINS IN EFFECT. UPDATE ISSUED AT 636 AM CDT THU AUG 6 2015 TIMING OF PRECIPITATION PROPAGATION NORTHEASTWARD WAS SLOWED BASED ON THE LATEST RADAR OBSERVATIONS. THE MAIN THREAT CONTINUES TO BE THE POTENTIAL FOR FLASH FLOODING ACROSS THE SOUTH CENTRAL/SOUTHEAST COUNTIES WHERE ECHO TRAINING HAS BEEN ONGOING FOR MUCH OF THE MORNING. INSTANTANEOUS RAIN RATES...SURFACE REPORTS OF RAINFALL...AND THE PRESENCE OF FREQUENT LIGHTENING SUGGESTS AN ABSENCE OF WARM RAIN PROCESSES. THUS...HELD OFF ON ISSUING ANY FLOOD ADVISORIES OR FLASH FLOOD WARNINGS IN DICKEY COUNTY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 340 AM CDT THU AUG 6 2015 HIGHLIGHTS OF THE SHORT TERM IS TIMING AND AREAL COVERAGE OF CONVECTION...AND THREAT OF HEAVY RAINFALL. CURRENTLY...AN UPPER LEVEL LOW/TROUGH WAS OVER THE ROCKIES...WITH A SERIES OF STRONG UPSTREAM SHORTWAVE ENERGY IMPULSES MOVING NORTHEAST FROM THE INTERMOUNTAIN WEST INTO THE NORTHERN PLAINS. AHEAD OF THE SYSTEM...AN ESTABLISHED SOUTHERLY LOW LEVEL JET OVER THE EASTERN DAKOTAS WAS ASSOCIATED WITH A SMALL CLUSTER OF THUNDERSTORMS OVER THE JAMES RIVER BASIN FROM MCINTOSH AND DICKEY COUNTIES IN NORTH DAKOTA SOUTHWARD TOWARDS ABERDEEN IN SOUTH DAKOTA. MEANWHILE OUT WEST...THE AFOREMENTIONED UPPER LEVEL TROUGH WAS ASSOCIATED WITH SCATTERED SHOWERS AND THUNDERSTORMS FROM SASKATCHEWAN TO EASTERN MONTANA TO THE DAKOTAS. THE LATEST NAM/HRRR AND HIGH RESOLUTION SHORT TERM MODELS INDICATE THAT MORE WIDESPREAD CONVECTION FROM EASTERN MONTANA AND WESTERN SOUTH DAKOTA WILL LIFT NORTHEASTWARD INTO NORTH DAKOTA THIS MORNING...WITH NUMEROUS SHOWERS AND THUNDERSTORMS OCCURRING FROM NORTHWEST TO SOUTHEASTERN NORTH DAKOTA THROUGH THE DAY...AS PER THE ARCING ORIENTATION OF THE UPPER LEVEL IMPULSES LIFTING NORTHEAST ACROSS THE STATE TODAY. ALONG WITH THUNDERSTORMS ASSOCIATED WITH THE LOW LEVEL JET PLAGUING THE JAMES RIVER BASIN...MORE CONVECTION IS EXPECTED LATER TODAY AS THE MAIN UPPER LEVEL IMPULSE SHORTWAVE MOVES ACROSS THE STATE...REACHING THE JAMES VALLEY THIS AFTERNOON. PWATS OF 1.50 WITH WARM RAIN PROCESSES IN PLAY WILL KEEP THE THREAT OF HEAVY RAINFALL OVER THE SOUTH CENTRAL. MAY NEED TO WATCH FOR FARTHER NORTH AND WEST FOR PERSISTENT RAINS LEADING TO SOME HEAVY RAINS. CONFIDENCE IS NOT HIGH ENOUGH TO EXPAND THE FLASH FLOOD WATCH. THE SYSTEM BEGINS MOVING EASTWARD OUT OF OUR AREA DURING THE EVENING. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 340 AM CDT THU AUG 6 2015 IN THE WAKE OF THE NORTHWESTERN U.S. TROUGH PROGRESSION INTO SOUTHEAST CANADA THIS WEEKEND...THE MAIN FORECAST FOCUS SHIFTS TO THE RETURN TO STRONG RIDGING OVER THE GREAT PLAINS AS A WEST COAST TROUGH BECOMES REESTABLISHED. RESULTANT DOWNSTREAM RIDGING ALOFT SHOULD REDUCE PRECIPITATION CHANCES AT LEAST DURING THE EARLY PART OF NEXT WEEK. BY WEDNESDAY NIGHT...THOUGH...THERE IS GOOD AGREEMENT AMONG THE 00 UTC ECMWF/GFS/GEFS THAT MID LEVEL SHORTWAVES WILL BEGIN TO EJECT INTO MONTANA...AND PERHAPS NORTH DAKOTA. CONSEQUENTLY...PRECIPITATION CHANCES RETURN WEDNESDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1219 PM CDT THU AUG 6 2015 WIDESPREAD IFR CONDITIONS IN STRATUS ACROSS CENTRAL AND NORTHWEST NORTH DAKOTA WILL SLOWLY LIFT INTO THE AFTERNOON. WIDESPREAD SHOWERS AND THUNDERSTORMS ARE ALSO EXPECTED FOR THESE AREAS THROUGH THE AFTERNOON...INCLUDING KISN/KMOT/KBIS/KJMS. KDIK LOOKS TO REMAIN WEST OF PRECIPITATION ACTIVITY FOR THE REMAINDER OF THE DAY. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 10 PM CDT THIS EVENING FOR NDZ022-023- 025-035>037-046>048-050-051. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...SCHECK AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1117 AM CDT THU AUG 6 2015 .UPDATE... ISSUED AT 1059 AM CDT THU AUG 6 2015 NO SIGNIFICANT CHANGES AT THIS TIME TO THE ONGOING FORECAST. THE QUESTION FOR THE AFTERNOON IS HOW MUCH INSTABILITY AND RESULT STORM COVERAGE AND INTENSITY CAN BE REALIZED GIVEN CURRENT CLOUD COVER ACROSS SOUTH CENTRAL NORTH DAKOTA AND INTO THE JAMES RIVER VALLEY. GIVEN RADAR TRENDS THROUGH 16 UTC...MAY BE ABLE TO TRIM A FEW COUNTIES OFF OF THE WESTERN PORTION OF THE FLASH FLOOD WATCH WHERE ONGOING WEAKER CONVECTION WILL PREVENT INSTABILITY BUILD UP NEEDED FOR DEEPER CONVECTION AND A FLASH FLOOD THREAT. THE 12-14 UTC HRRR ITERATIONS AND 12 UTC GLOBAL SUITE STILL SUGGEST STORM COVERAGE AND INTENSITY INCREASING THROUGH THE AFTERNOON SOUTH CENTRAL AND INTO SOUTHEAST NORTH DAKOTA. AS STATED ABOVE...CLOUD COVER DOES ADD UNCERTAINTY TO THIS SOLUTION...HOWEVER...THE STRONG SHORTWAVE STILL REMAINS TO THE WEST OF THESE AREAS WHICH MAY PROVIDE ENOUGH FORCING TO OVERCOME THIS ISSUE. UPDATE ISSUED AT 832 AM CDT THU AUG 6 2015 SHOWERS/STORMS CONTINUE TO LIFT TO THE NORTHEAST VERY SLOWLY...WITH SOME AREAS OF PRECIPITATION REMAINING NEARLY STATIONARY OVER PORTIONS OF THE SOUTHERN JAMES RIVER VALLEY. LATEST HIGH REST GUIDANCE CONTINUES TO INDICATE SLOW STORM MOTION THROUGH THE REST OF THE DAY...THEREFORE THE FLOODING THREAT WILL CONTINUE...PARTICULARLY OVER SOUTH CENTRAL INTO THE JAMES RIVER VALLEY WHERE CURRENT FLASH FLOOD WATCH REMAINS IN EFFECT. UPDATE ISSUED AT 636 AM CDT THU AUG 6 2015 TIMING OF PRECIPITATION PROPAGATION NORTHEASTWARD WAS SLOWED BASED ON THE LATEST RADAR OBSERVATIONS. THE MAIN THREAT CONTINUES TO BE THE POTENTIAL FOR FLASH FLOODING ACROSS THE SOUTH CENTRAL/SOUTHEAST COUNTIES WHERE ECHO TRAINING HAS BEEN ONGOING FOR MUCH OF THE MORNING. INSTANTANEOUS RAIN RATES...SURFACE REPORTS OF RAINFALL...AND THE PRESENCE OF FREQUENT LIGHTENING SUGGESTS AN ABSENCE OF WARM RAIN PROCESSES. THUS...HELD OFF ON ISSUING ANY FLOOD ADVISORIES OR FLASH FLOOD WARNINGS IN DICKEY COUNTY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 340 AM CDT THU AUG 6 2015 HIGHLIGHTS OF THE SHORT TERM IS TIMING AND AREAL COVERAGE OF CONVECTION...AND THREAT OF HEAVY RAINFALL. CURRENTLY...AN UPPER LEVEL LOW/TROUGH WAS OVER THE ROCKIES...WITH A SERIES OF STRONG UPSTREAM SHORTWAVE ENERGY IMPULSES MOVING NORTHEAST FROM THE INTERMOUNTAIN WEST INTO THE NORTHERN PLAINS. AHEAD OF THE SYSTEM...AN ESTABLISHED SOUTHERLY LOW LEVEL JET OVER THE EASTERN DAKOTAS WAS ASSOCIATED WITH A SMALL CLUSTER OF THUNDERSTORMS OVER THE JAMES RIVER BASIN FROM MCINTOSH AND DICKEY COUNTIES IN NORTH DAKOTA SOUTHWARD TOWARDS ABERDEEN IN SOUTH DAKOTA. MEANWHILE OUT WEST...THE AFOREMENTIONED UPPER LEVEL TROUGH WAS ASSOCIATED WITH SCATTERED SHOWERS AND THUNDERSTORMS FROM SASKATCHEWAN TO EASTERN MONTANA TO THE DAKOTAS. THE LATEST NAM/HRRR AND HIGH RESOLUTION SHORT TERM MODELS INDICATE THAT MORE WIDESPREAD CONVECTION FROM EASTERN MONTANA AND WESTERN SOUTH DAKOTA WILL LIFT NORTHEASTWARD INTO NORTH DAKOTA THIS MORNING...WITH NUMEROUS SHOWERS AND THUNDERSTORMS OCCURRING FROM NORTHWEST TO SOUTHEASTERN NORTH DAKOTA THROUGH THE DAY...AS PER THE ARCING ORIENTATION OF THE UPPER LEVEL IMPULSES LIFTING NORTHEAST ACROSS THE STATE TODAY. ALONG WITH THUNDERSTORMS ASSOCIATED WITH THE LOW LEVEL JET PLAGUING THE JAMES RIVER BASIN...MORE CONVECTION IS EXPECTED LATER TODAY AS THE MAIN UPPER LEVEL IMPULSE SHORTWAVE MOVES ACROSS THE STATE...REACHING THE JAMES VALLEY THIS AFTERNOON. PWATS OF 1.50 WITH WARM RAIN PROCESSES IN PLAY WILL KEEP THE THREAT OF HEAVY RAINFALL OVER THE SOUTH CENTRAL. MAY NEED TO WATCH FOR FARTHER NORTH AND WEST FOR PERSISTENT RAINS LEADING TO SOME HEAVY RAINS. CONFIDENCE IS NOT HIGH ENOUGH TO EXPAND THE FLASH FLOOD WATCH. THE SYSTEM BEGINS MOVING EASTWARD OUT OF OUR AREA DURING THE EVENING. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 340 AM CDT THU AUG 6 2015 IN THE WAKE OF THE NORTHWESTERN U.S. TROUGH PROGRESSION INTO SOUTHEAST CANADA THIS WEEKEND...THE MAIN FORECAST FOCUS SHIFTS TO THE RETURN TO STRONG RIDGING OVER THE GREAT PLAINS AS A WEST COAST TROUGH BECOMES REESTABLISHED. RESULTANT DOWNSTREAM RIDGING ALOFT SHOULD REDUCE PRECIPITATION CHANCES AT LEAST DURING THE EARLY PART OF NEXT WEEK. BY WEDNESDAY NIGHT...THOUGH...THERE IS GOOD AGREEMENT AMONG THE 00 UTC ECMWF/GFS/GEFS THAT MID LEVEL SHORTWAVES WILL BEGIN TO EJECT INTO MONTANA...AND PERHAPS NORTH DAKOTA. CONSEQUENTLY...PRECIPITATION CHANCES RETURN WEDNESDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1059 AM CDT THU AUG 6 2015 WIDESPREAD IFR CONDITIONS IN STRATUS ACROSS CENTRAL AND NORTHWEST NORTH DAKOTA WILL SLOWLY LIFT INTO THE AFTERNOON. WIDESPREAD SHOWERS AND THUNDERSTORMS ARE ALSO EXPECTED FOR THESE AREAS THROUGH THE AFTERNOON...INCLUDING KISN/KMOT/KBIS/KJMS. KDIK LOOKS TO REMAIN WEST OF PRECIPITATION ACTIVITY FOR THE REMAINDER OF THE DAY. && .BIS WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 10 PM CDT /9 PM MDT/ THIS EVENING FOR NDZ019>023-025-034>037-042-045>048-050-051. && $$ UPDATE...AYD SHORT TERM...JV LONG TERM...SCHECK AVIATION...AYD
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
105 PM CDT THU AUG 6 2015 .AVIATION... THERE IS A SLIM...ABOUT 10 PERCENT...CHANCE OF A HIGH-BASED T-STORM IN THE VICINITY OF KPVW BETWEEN 21 UTC AND 02 UTC. OTHERWISE...VFR CONDITIONS WILL PREVAIL WITH SURFACE WINDS REMAINING MAINLY SOUTH TO SOUTHWEST AND BECOMING A BIT GUSTY IN THE AFTERNOON HOURS. && .PREV DISCUSSION... /ISSUED 659 AM CDT THU AUG 6 2015/ AVIATION... UPPER LEVEL HIGH PRESSURE RIDGE WILL EXPAND FURTHER ACROSS THE SOUTHERN PLAINS REGION TODAY AND TONIGHT LEADING TO HOT AND MOSTLY DRY CONDITIONS. LINGERING MID LEVEL MOISTURE AND WEAK CONVERGENCE WITHIN A SURFACE TROUGH COULD LEAD TO ISOLATED HIGH-BASED THUNDERSTORMS LATER THIS AFTERNOON UNTIL EARLY THIS EVENING NORTH- NORTHWEST OF KLBB BUT POSSIBLY NEAR KPVW. COVERAGE EXPECTED TO BE TOO SPARSE FOR INCLUSION WITHIN THE KPVW TAF FOR NOW. RMCQUEEN PREV DISCUSSION... /ISSUED 357 AM CDT THU AUG 6 2015/ SHORT TERM... UPPER LEVEL HIGH PRESSURE WILL CONTINUE TO EXPAND ACROSS THE AREA TODAY AND TONIGHT. THIS WILL LEAD TO BETTER SURFACE WARMING WITH HIGHS TODAY A DEGREE OR MAYBE TWO WARMER FOR MOST OF THE AREA...AND SHOULD BE THE HOTTEST DAY OF SUMMER SO FAR. SURFACE MOISTURE STILL ELEVATED THOUGH WILL TREND DOWNWARDS DURING THE PEAK MIXING PERIOD THIS AFTERNOON...SO WILL ALSO LIMIT HEAT INDEX VALUES SOMEWHAT. WE REMAIN A BIT UNCERTAIN IF MODELS ARE CORRECTLY FORECASTING SURFACE DEWPOINT VALUES...AND IF UNDERPLAYED BY ONLY 2 OR 3 DEGREES MAY REQUIRE CONSIDERATION OF A HEAT ADVISORY IN THE SOUTHEAST CORNER OF OUR AREA. BUT FOR NOW WE SIDE WITH THE BULK OF OUR GUIDANCE WHICH COMES UP JUST SHORT OF HEAT ADVISORY LEVELS. WHILE THE UPPER RIDGE WILL CONTINUE TO EXPAND...CAPPING STILL LOOKS MARGINAL AND ACTUALLY FORECAST TO WEAKEN DURING PEAK DEEP MIXING ACROSS THE NORTHWEST CORNER OF OUR AREA. A SHORT WAVE PASSING BY TO THE NORTH WILL DRAG ANOTHER BATCH OF LIMITED MID LEVEL MOISTURE ACROSS THIS AREA THIS AFTERNOON AND EARLY EVENING. A SURFACE TROUGH ALSO WILL PROVIDE WEAK CONVERGENCE IN OUR NORTHWEST. SHORT RANGE SOLUTIONS OF RAP AND HRRR HAVE ONCE AGAIN BEEN INSISTENT TONIGHT ON ISOLATED TO WIDELY SCATTERED COVERAGE OF HIGH-BASED THUNDERSTORMS LATE THIS AFTERNOON INTO THE EARLY EVENING...ALTHOUGH LESS COVERAGE THAN EXPERIENCED YESTERDAY. SURFACE BASED CAPES APPEAR MOSTLY UNDER 1000 JOULES PER KILOGRAM LATER TODAY SO STORMS MAY HAVE A LITTLE LESS OOMPH AS WELL. EVEN SO...WE WILL INCLUDE A SLIGHT CHANCE FOR THUNDERSTORMS FOR LATER THIS AFTERNOON AND EARLY THIS EVENING IN OUR NORTHWEST CORNER. ANY STORMS SHOULD QUICKLY DISSIPATE WITH LOSS OF SURFACE HEATING EARLY THIS EVENING AND ANOTHER QUIET AND MILD NIGHT WILL FOLLOW. RMCQUEEN LONG TERM... FRIDAY AND INTO THE WEEKEND WILL REMAIN HOT...ALTHOUGH A COUPLE OF DEGREES COOLER THAN TODAY AS THE UPPER HIGH IS NUDGED EAST AHEAD OF A DISTURBANCE PUSHING ONSHORE CENTRAL CALIFORNIA. HIGH TEMPERATURES WILL REMAIN MOSTLY IN THE MID 90S TO NEAR THE CENTURY MARK ON THE CAPROCK WHILE LOCALES IN THE ROLLING PLAINS AND FAR SOUTHEAST PANHANDLE RESIDE IN THE UPPER 90S TO AROUND 104-105 DEGREES. LATE SUNDAY CONTINUES TO BEAR WATCHING IN TERMS OF ISOLATED THUNDERSTORM POTENTIAL NEAR THE FAR SOUTHWEST PANHANDLE INTO THE NORTHERN SOUTH PLAINS. ENERGY FROM THE PREVIOUSLY MENTIONED DISTURBANCE...AT THIS TIME ROTATING THROUGH THE NORTHERN PLAINS INTO THE UPPER MIDWEST...WILL SEND A FRONTAL BOUNDARY SOUTHWARD THROUGH THE PLAINS. AT THE SAME TIME...A SUBTROPICAL MOISTURE PLUME WILL ATTEMPT TO BEND EASTWARD ACROSS THE TEXAS/NEW MEXICO BORDER. WHETHER THIS ENHANCED MID-UPPER MOISTURE MAKES IT INTO THE LONE STAR STATE WILL DEPEND ON PLACEMENT OF THE UPPER HIGH AS LATER SUNDAY LOOKS TO BE THE TIME AT WHICH THIS FEATURE BEGINS RETROGRADING WESTWARD. BELIEVE ENOUGH CONSISTENCY HAS BEEN SHOWN AT THIS TIME TO WARRANT SLIGHT CHANCE MENTION ACROSS PARMER COUNTY...BUT WILL CONTINUE TO MONITOR SAID UNCERTAINTIES GOING FORWARD. HEADING INTO NEXT WEEK...UPPER HIGH STILL LOOKS TO BUILD WEST AND NORTHWEST WHILE AMPLIFYING...THUS SHIFTING THE H85 THERMAL RIDGE AXIS IN THE SAME DIRECTION AND KEEPING TEMPERATURES MAINLY IN THE 90S LOCALLY. CYCLONIC FLOW FROM EASTERN CANADA BACK INTO THE OHIO VALLEY LOOKS TO KEEP SOME SEMBLANCE OF A FRONTAL BOUNDARY IN PLACE AHEAD OF A SURFACE RIDGE PUSHING SOUTH THROUGH THE MISSISSIPPI VALLEY. NWP NOW SUGGESTING THAT A PERIOD OF CONTINUED UPSLOPE FLOW MAY THEREFORE BE IN THE OFFING FOR A PERIOD NEXT WEEK ALONG WITH CONTINUED ENHANCED MOISTURE TRAPPED UNDERNEATH THE UPPER HIGH. HAVE KEPT CONDITIONS DRY FOR NOW AFTER SUNDAY EVENING GIVEN THE UNCERTAINTY IN THE DETAILED SYNOPTIC EVOLUTION AND EXTENT/AMOUNT OF MOISTURE THAT WILL BE AVAILABLE. THUNDERSTORM CHANCES AND COOLER TEMPERATURES WOULD BE THE SENSIBLE WEATHER RESULTS IF THIS SCENARIO DOES INDEED PLAY OUT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 69 97 67 97 / 0 0 0 0 TULIA 70 98 69 98 / 10 0 0 0 PLAINVIEW 71 98 70 97 / 10 0 0 0 LEVELLAND 71 99 70 98 / 0 0 0 0 LUBBOCK 74 100 72 98 / 0 0 0 0 DENVER CITY 70 99 70 98 / 0 0 0 0 BROWNFIELD 71 99 71 98 / 0 0 0 0 CHILDRESS 76 104 75 103 / 0 0 0 0 SPUR 75 102 73 101 / 0 0 0 0 ASPERMONT 78 104 77 104 / 0 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 33