Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/26/15


AREA FORECAST DISCUSSION
NWS TUCSON AZ
900 PM MST SAT APR 25 2015 .SYNOPSIS...EXPECT SCATTERED TO NUMEROUS SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS INTO SUNDAY AS A STRONG LOW PRESSURE SYSTEM MOVES ACROSS THE FOUR CORNERS REGION. COOLER TEMPERATURES WILL ALSO OCCUR SUNDAY. A FEW SHOWERS MAY OCCUR ACROSS THE WHITE MOUNTAINS MONDAY AND TUESDAY. THEREAFTER...DRY CONDITIONS WITH WELL ABOVE NORMAL DAYTIME TEMPERATURES WILL PREVAIL WEDNESDAY THROUGH SATURDAY. && .DISCUSSION...KEMX WSR-88D DETECTED ISOLATED 35-45 DBZ ECHOES ACROSS FAR WRN PIMA COUNTY NE OF AJO AT 0355Z. SCATTERED MOSTLY LESS THAN 30 DBZ ECHOES EXTENDED FROM TUCSON NWD ACROSS SERN PINAL/FAR WRN GRAHAM COUNTIES. CELL MOVEMENT WAS GENERALLY TO THE NORTHEAST AROUND 20 KTS. A DEEPENING UPPER TROUGH EXTENDED FROM THE SWRN CONUS INTO THE PACIFIC NW THIS EVENING. A 554 DM LOW PRESSURE CENTER IS PROGGED VIA THE 26/00Z NAM AND 26/18Z GFS TO BE OVER NERN ARIZONA AROUND DAYBREAK SUN. HAVE NOTED THAT THE 26/00Z NAM INCREASED POPS FAIRLY SUBSTANTIALLY FOR THE REST OF TONIGHT...ESPECIALLY FROM TUCSON NWD... VERSUS PREVIOUS SOLUTIONS. HAVE ALSO NOTED THAT SEVERAL RUC HRRR SOLUTIONS HAVE GENERALLY TRENDED HIGHER WITH PROGGED LIQUID RAIN AMOUNTS THRU 12Z-15Z SUNDAY. ACCORDING TO THE 26/02Z HRRR...THE TIMING FOR THE BEST CHANCE OF MEASURABLE RAINFALL FOR THE TUCSON METRO AREA WILL OCCUR FROM 05Z-12Z SUNDAY OR SO. BASED ON RADAR TRENDS AS WELL AS THE MOST RECENT RUC/NAM SOLUTIONS... HAVE INCREASED POPS FOR THE REST OF TONIGHT...PARTICULARLY FROM TUCSON NWD ACROSS SERN PINAL/WRN GRAHAM COUNTIES. HAVE ALSO ADDED A SLIGHT CHANCE OF THUNDERSTORMS ACROSS MUCH OF THE AREA THE REST OF TONIGHT. THE BULK OF THE PRECIPITATION SUNDAY SHOULD OCCUR NE OF TUCSON...OR ACROSS NRN GREENLEE/GRAHAM COUNTIES. HAVE ALSO ADDED A SLIGHT CHANCE OF THUNDERSTORMS ACROSS MUCH OF THE AREA SUNDAY MORNING. AT THIS TIME...APPEARS THAT SNOW LEVELS BY MIDDAY SUN WILL BE AROUND 7000 FEET ACROSS THE WHITE MOUNTAINS TO AROUND 8000 FEET ACROSS THE CATALINA/RINCON MOUNTAINS NEAR TUCSON. SEVERAL INCHES OF SNOW IS POSSIBLE BY SUNDAY EVENING ACROSS THE WHITE MOUNTAINS ABOVE 7000 FEET...WITH 2 TO 4 INCHES OF SNOW ABOVE 7000 FEET ACROSS THE CATALINA/RINCON MOUNTAINS AS WELL AS THE GALIURO/PINALENO MOUNTAINS IN GRAHAM COUNTY. GUSTY WEST TO SOUTHWEST WINDS WILL CONTINUE FOR MOST LOCATIONS THE REST OF TONIGHT FOLLOWED BY GUSTY WEST TO NORTHWEST WINDS SUNDAY. COOLER TEMPS WILL OCCUR SUN AS THE UPPER LOW BECOMES QUASI-STATIONARY OVER NRN NEW MEXICO. PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL. && .AVIATION...VALID THRU 27/06Z. EXPECT SCATTERED TO NUMEROUS -SHRA ALONG WITH ISOLATED -TSRA THRU SUNDAY AFTERNOON. THE BEST CHANCE FOR PRECIPITATION WILL BE NORTH OF A SAN SIMON-KTUS-SELLS LINE. MVFR CONDITIONS MAY OCCUR ESPECIALLY NEAR THE HIGHER TERRAIN NE OF KTUS TO THE WHITE MOUNTAINS. ISOLATED TO SCATTERED -SHRA SUNDAY EVENING SHOULD BE CONFINED FROM VICINITY OF KSAD TO THE WHITE MOUNTAINS. OTHERWISE...CLOUD DECKS INTO MIDDAY SUNDAY WILL GENERALLY BE AT 6-10K FT AGL. GRADUALLY CLEARING SKIES WILL THEN OCCUR FROM WEST-TO- EAST ACROSS SOUTHEAST ARIZONA SUNDAY AFTERNOON AND SUNDAY EVENING. SURFACE WIND THE REST OF TONIGHT WILL MAINLY BE WLY/SWLY AT 10-20 KTS WITH GUSTS TO AROUND 25 KTS. SURFACE WIND SUNDAY WILL BE WLY/NWLY AT 12-25 KTS WITH GUSTS OF 30-40 KTS. THE STRONGEST WIND IS EXPECTED TO OCCUR NEAR THE NEW MEXICO BORDER. SURFACE WIND WILL DIMINISH TO AROUND 10 KTS MOST SECTIONS TOWARD THE END OF THE PERIOD...OR 27/06Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...A STRONG LOW PRESSURE SYSTEM MOVING NORTH OF THE AREA WILL BRING A GOOD CHANCE OF SHOWERS AND PERHAPS A FEW THUNDERSTORMS INTO SUNDAY. THE BEST CHANCE FOR PRECIPITATION IS NORTH OF TUCSON. A FEW SHOWERS MAY OCCUR ACROSS THE WHITE MOUNTAINS MONDAY AND TUESDAY. THEREAFTER...DRY CONDITIONS WITH WELL ABOVE NORMAL DAYTIME TEMPERATURES WILL PREVAIL WEDNESDAY THROUGH SATURDAY. EXPECT GUSTY WEST TO NORTHWEST WINDS SUNDAY ASSOCIATED WITH THE LOW PRESSURE SYSTEM. GUSTY EAST WINDS SHOULD OCCUR TUESDAY. && .PREV DISCUSSION...THE SYSTEM WILL CONTINUE TO EXIT TO THE EAST INTO THE CENTRAL AND SOUTHERN PLAINS MONDAY BUT THE TAIL END OF THIS SYSTEM WILL LINGER BACK ACROSS PARTS OF THE DESERT SOUTHWEST. A SHARP MOISTURE GRADIENT IS ADVERTISED BY THE MODELS TO BE RIGHT ALONG THE AZ/NM BORDER MONDAY INTO TUESDAY RESULTING IN LINGERING ISOLATED SHOWERS...MAINLY OVER THE WHITE MOUNTAINS...BUT DRY ELSEWHERE. BEHIND THIS SYSTEM RIDGING WILL NOSE IN ACROSS SOUTHERN CALIFORNIA AND THE GREAT BASIN LATE TUESDAY AND OVER ARIZONA ON WEDNESDAY AND CONTINUING INTO THURSDAY. BEYOND THURSDAY MODELS SHOW SIGNIFICANT DISCREPANCIES...SO DID NOT MAKE ANY CHANGES TO THE FORECAST... ALTHOUGH AT THIS TIME IT LOOKS LIKE A DRY FORECAST IS IN STORE REGARDLESS OF THE UNCERTAINTY AMONG THE MODELS. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON FRANCIS PREVIOUS DISCUSSION...MOLLERE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1000 AM MST FRI APR 24 2015 .SYNOPSIS... A SERIES OF PACIFIC WEATHER DISTURBANCES WILL SLOWLY MOVE THROUGH THE REGION TODAY AND THIS WEEKEND...PROVIDING COOLER TEMPERATURES AND MORE HUMID CONDITIONS. A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS IS FORECAST OVER THE SOUTH CENTRAL ARIZONA MOUNTAINS TODAY...WITH A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS SATURDAY NIGHT IN SOUTHWEST AND SOUTH CENTRAL ARIZONA. A STRONG COLD FRONT IS FORECAST TO MOVE INTO CENTRAL ARIZONA SATURDAY NIGHT. CLEARING SKIES ARE EXPECTED BY LATER SUNDAY WITH DRY AND MUCH WARMER WEATHER NEXT WEEK. && .DISCUSSION... UPPER TROUGH AXIS IS OVER ARIZONA THIS MORNING EXTENDING SOUTHWESTWARD ACROSS NORTHERN BAJA MEXICO. THE MAIN VORT MAX WITHIN THE TROUGH IS ALREADY OVER NEW MEXICO. A WEAKER TRAILING VORT MAX HAS BEEN HELPING TO PRODUCE ISOLATED TO SCATTERED SHOWERS OVER MARICOPA...PINAL...AND GILA COUNTIES. CAPE LOOKS QUITE MODEST BUT JUST ENOUGH TO GET SOME STRAY SHOWERS THAT HAVE HEAVIER SHOWERS WITH THEM THAN THE OTHERS. COULD POSSIBLY GET A DEEP ENOUGH SHOWER TO GET A RUMBLE OF THUNDER. EVEN IN THAT SCENARIO...NOT LOOKING AT ANY FLOODING ISSUES AS IT WOULD BE VERY LOCALIZED AND BRIEF. HRRR KEEPS ISOLATED SHOWER ACTIVITY GOING INTO THE AFTERNOON WHILE OTHER HI RES MODELS TREND THINGS DOWN QUICKLY AFTER MIDDAY. WILL MAKE SOME MINOR ADJUSTMENTS TO KEEP POPS GOING PAST 18Z TODAY. NEXT SYSTEM BEGINS ENTERING OUR FORECAST AREA SATURDAY AFTERNOON WITH THE MAIN DYNAMICAL PUSH HAPPENING BETWEEN 00Z-18Z SUNDAY. MORE LATER. && .PREVIOUS DISCUSSION ISSUED 305 AM MST/PDT... TODAY... A BROAD COOL LOW PRESSURE SYSTEM WAS SLOWLY MOVING THROUGH CENTRAL ARIZONA EARLY THIS MORNING FROM THE WEST. 00Z PLOT DATA... 5PM LAST EVENING DETECTED A CONSIDERABLE AMOUNT OF BOUNDARY LAYER MOISTURE 7000 FEET DEEP SPREADING ACROSS THE COLORADO RIVER FROM SOUTHERN CA. THIS IS A SIGNIFICANT AMOUNT OF MOISTURE RELATIVE TO TEMPS ALOFT...AND WILL SPREAD EAST ACROSS AZ TODAY. AS THE UPPER LOW SLOWLY MOVED INTO AZ OVERNIGHT...SHOWERS AND THUNDERSTORMS WERE NOTED IN FAR SOUTHEAST AZ JUST BEFORE MIDNIGHT... WITH ISOLATED SHOWERS AND THUNDERSTORMS IN MARICOPA COUNTY JUST NORTH OF PHOENIX AT 2 AM. CURRENT FORECASTS HANG ON TO A SLIGHT CHANCE OF SHOWERS THROUGH THE FRIDAY MORNING HOURS...WITH THE SHOWER THREAT ENDING IN ALL BUT SOUTHERN GILA COUNTY ZONE 24 BY EARLY AFTERNOON. TONIGHT AND SATURDAY... ALTHOUGH CONSIDERABLE BOUNDARY LAYER MOISTURE WILL RESIDE OVER THE FORECAST AREA...SOUTHEAST CA TO SOUTH CENTRAL AZ...THE ATMOSPHERE WILL BE TOO STABLE TO GENERATE ANY SHOWER ACTIVITY. THEREFORE PARTLY CLOUDY SKIES WITH BELOW NORMAL TEMPERATURES ARE FORECAST AREA-WIDE. SATURDAY NIGHT AND SUNDAY... A POWERFUL NEGATIVE TILT TROF IS STILL FORECAST TO RAPIDLY DEEPEN INTO CENTRAL AZ SATURDAY NIGHT. IN FACT... THE STRONGEST VERTICAL MOTION FIELD...REPLETE WITH POSSIBLE HEAVY SHOWERS AND THUNDERSTORMS WILL BECOME FOCUSED BETWEEN PRESCOTT AND QUARTZSITE BY 9 PM SATURDAY...OR IN LA PAZ AND NORTHWEST MARICOPA COUNTIES...THEN SPREAD EAST ACROSS THE PHOENIX AREA BY 2 AM SATURDAY NIGHT. SINCE BOUNDARY LAYER MOISTURE WILL BE RELATIVELY DEEP...THIS CLASSIC FAST MOVING COLD FRONT MAY RESULT IN A LINE OF SHWRS/TSTMS WITH POTENTIAL FOR BRIEF HEAVY RAIN AND STRONG WIND. PORTIONS OF SOUTHEAST CA IN RIVERSIDE COUNTY MAY SEE A FEW SHOWERS/SLIGHT CHANCE OF THUNDERSTORMS EARLY SATURDAY EVENING...BUT MOST OF THE ACTIVITY WILL BE CONFINED TO ARIZONA. THE COLD FRONT BY 7 AM SUNDAY SHOULD HAVE MOVED TO THE EASTERN AZ BORDER RESULTING IN LINGERING SHOWERS OR UNSETTLED CONDITIONS OVER SOUTH CENTRAL ARIZONA SUNDAY AFTERNOON...MAINLY PHOENIX EASTWARD. CLEARING SUNDAY NIGHT. MONDAY THROUGH THURSDAY... DRY NORTHERLY FLOW WILL DEVELOP MONDAY AND TUESDAY FOLLOWED BY A BUILDING RIDGE OVER THE REGION WEDNESDAY AND THURSDAY. MUCH WARMER TEMPERATURES ARE FORECAST WEDNESDAY WITH NEAR 100 DEGREE HEAT ON THE WARMEST DESERTS. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL... SCATTERED SHOWERS CONTINUE ACROSS THE AREA THIS MORNING AND WILL PERSIST INTO THE EARLY AFTERNOON HOURS. KIWA/KSDL THE MOST LIKELY TO SEE SHOWERS AT THE AIRFIELD WHILE KPHX MAY ONLY SEE VCSH BASED ON RADAR TRENDS. WIDESPREAD CIGS AROUND 6KFT WILL BE COMMON THROUGH LATE AFTERNOON. OTHERWISE EXPECT CONDITIONS TO IMPROVE LATE THIS AFTERNOON/EVENING. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... FEW-SCT HIGH CLOUDS FROM FRIDAY MORNING ONWARD. PASSING UPPER LEVEL TROUGH WILL CONTINUE ELEVATED WINDS...WITH GUSTS INTO TO 20KT RANGE PSBL THROUGHOUT THE DAY. STRONGER WINDS IN THE FORECAST FOR SATURDAY...WITH GUSTS PUSHING 35KTS PARTICULARLY ACROSS IMPERIAL COUNTY AND KIPL. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... SUNDAY THROUGH THURSDAY... FINAL PIECE OF A POTENT UPPER LEVEL TROUGH WILL SWIFTLY MOVE THROUGH THE REGION SUNDAY...SUPPORTING ADDITIONAL BREEZY TO LOCALLY WINDY CONDITIONS. DEWPOINTS WILL SLOWLY DRY IN THE WAKE OF A PASSING COOL FRONT...BUT CRITICALLY LOW HUMIDITIES WILL GENERALLY BE OFFSET OF THE STRONGEST WINDS AND EVEN THEN ONLY DRY INTO THE 20 PERCENT RANGE OR SO ON SUNDAY. THE MAIN TROUGH FEATURE WILL CLEAR THE AREA SUNDAY NIGHT/MONDAY...WITH RESIDUAL WEAK TROUGH HEIGHTS LINGERING OVER THE SOUTHWEST. DRY AIR WILL CONTINUE TO SETTLE INTO THE REGION WHILE TEMPERATURES WARM TO MORE SEASONAL...AND EVEN ABOVE SEASONAL...READINGS. THIS WILL RESULT IN SINGLE DIGIT AFTERNOON HUMIDITIES WITH FAIR OVERNIGHT RECOVERIES. WINDS FROM MONDAY ONWARD WILL GENERALLY BE LIGHT AND WILL FOLLOW TYPICAL DIURNAL TRENDS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...WIND ADVISORY FROM 1 PM TO 9 PM PDT SATURDAY FOR CAZ030>033. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...AJ PREVIOUS DISCUSSION...VASQUEZ AVIATION...LEINS FIRE WEATHER...NOLTE/LEINS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
850 AM MST FRI APR 24 2015 .SYNOPSIS...A WEAK AREA OF LOW PRESSURE WILL MOVE ACROSS THE STATE TODAY...RESULTING IN A CHANCE OF SHOWERS AND THUNDERSTORMS MAINLY FROM TUCSON WEST AND NORTH. DRY CONDITIONS WILL PREVAIL AREA-WIDE ON SATURDAY. A STRONG LOW PRESSURE SYSTEM WILL THEN MOVE INTO THE REGION SATURDAY NIGHT AND SUNDAY. THIS SYSTEM WILL BRING GUSTY WINDS...COOLER TEMPERATURES AND A GOOD CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS TO THE EASTERN HALF OF SOUTHERN ARIZONA SATURDAY NIGHT AND SUNDAY. DRY CONDITIONS WILL RETURN TO START THE WORK WEEK...ALONG WITH A STRONG WARMING TREND TUESDAY THROUGH THURSDAY. && .DISCUSSION...ISOLATED SHOWERS HAVE DEVELOPED THIS MORNING AS UPPER LEVEL TROF MOVES ACROSS THE AREA. LATEST HRRR RUNS INDICATE THAT ISOLATED SHOWERS WILL BE AROUND MAINLY FROM TUCSON WEST AND NORTH INTO THE AFTERNOON HOURS. HAVE UPDATED THE FORECAST FOR THIS MORNING TIME FRAME TO ADD ISOLATED SHOWERS...MAINLY FROM TUCSON WEST AND NORTH...AND WILL CONTINUE TO LOOK AT NEW MODEL DATA FOR THE AFTERNOON PART OF THE TODAYS FORECAST SHORTLY. && .AVIATION...VALID THRU 25/18Z. SCT-BKN CLOUD DECKS 5-8 KFT AGL PRIMARILY NW OF KFHU-KCLT LINE WITH ISOLATED -SHRA/TS THROUGH 25/03Z. LIGHT WINDS LESS THAN 10 KTS...THEN SWLY TO WLY WINDS OF 12- 20 KTS WITH OCCASIONAL GUSTS TO 30 KTS THIS AFTERNOON WITH THE HIGHEST WIND SPEEDS SOUTH AND EAST OF KTUS. CLEARING SKIES ALONG WITH TYPICAL DIURNAL WINDS DEVELOPING AFTER 25/03Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...ISOLATED SHOWERS...POSSIBLY A THUNDERSTORM...FROM TUCSON WEST AND NORTH TODAY. IN ADDITION...BREEZY WEST TO SOUTHWEST WINDS OF 15 TO 20 MPH WITH AN OCCASIONAL GUST TO 35 MPH WILL DEVELOP AGAIN THIS AFTERNOON. THE STRONGEST WINDS WILL OCCUR SOUTH AND EAST OF TUCSON. ANY SHOWERS OR STORMS WILL BE CAPABLE OF PRODUCING BRIEF GUSTY AND ERRATIC WINDS. DRY CONDITIONS ARE EXPECTED TONIGHT AND SATURDAY. THEREAFTER...ANOTHER STORM SYSTEM WILL APPROACH THE REGION WHICH WILL BRING ANOTHER ROUND OF ELEVATED WINDS AND A CHANCE OF SHOWERS AND THUNDERSTORMS SATURDAY NIGHT THROUGH SUNDAY. THIS AREA OF DISTURBED WEATHER WILL QUICKLY EXIT THE AREA RESULTING IN DRY CONDITIONS RETURNING SUNDAY NIGHT THROUGH THE END OF NEXT WEEK. A SUBSTANTIAL WARMING TREND IS ANTICIPATED STARTING MONDAY...WITH CURRENT INDICATIONS POINTING TO HIGH TEMPERATURES INCREASING TO 6-12 DEGREES ABOVE NORMAL BY THE END OF THE WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1025 PM PDT THU APR 23 2015 .UPDATE... A QUICK FORECAST UPDATE WILL BE SENT SHORTLY TO INCREASE POPS NORTH OF I-80, AND EXTEND THUNDER INTO PARTS OF NORTHERN CA LATER INTO THE NIGHT. CLUSTER OF THUNDERSTORMS WITH IMPRESSIVE LIGHTNING OUTPUT WHICH DEVELOPED OVER THE NORTHERN SACRAMENTO VALLEY EARLIER THIS EVENING CONTINUE TO MARCH EAST, WITH STEADY PRECIP SPREADING MAINLY FROM CENTRAL PLUMAS COUNTY SOUTH TO THE TAHOE BASIN. ALTHOUGH THE LIGHTNING ACTIVITY SHOULD GRADUALLY DIMINISH OVERNIGHT, IT APPEARS THAT SOME STRIKES SHOULD SPREAD ACROSS EASTERN PLUMAS AND SIERRA COUNTIES SOUTHWARD TO THE NORTH AND WEST SHORES OF THE TAHOE BASIN. IN THESE AREAS WE EXTENDED MENTION OF THUNDER THRU 2 AM. SEVERAL RUNS OF THE HRRR HAVE SPREAD RAIN FROM THIS CONVECTIVE CLUSTER INTO WESTERN NV MAINLY NORTH OF I-80 THRU THE OVERNIGHT HOURS. IN THESE AREAS WE INCREASED SHOWER COVERAGE AND QPF VALUES, WITH AMOUNTS RANGING FROM 0.10 TO 0.25 INCH OVERNIGHT. THE HEAVIEST RAIN TOTALS ARE LIKELY ALONG AND WEST OF HIGHWAY 89 NORTH OF TRUCKEE, WHERE LOCAL AMOUNTS UP TO 0.50 INCH ARE POSSIBLE. MJD && .PREVIOUS DISCUSSION... /ISSUED 215 PM PDT THU APR 23 2015/ SYNOPSIS... LOW PRESSURE WILL DOMINATE THROUGH SATURDAY WITH CHANCES FOR RAIN AND HIGH ELEVATION SNOW ALONG WITH BREEZY CONDITIONS. THE BEST CHANCE OF RAIN AND SNOW WILL ARRIVE LATE FRIDAY NIGHT INTO SATURDAY MORNING WITH POTENTIAL TRAVEL PROBLEMS IN THE SIERRA AND NORTHEAST CALIFORNIA. HIGH PRESSURE WILL BUILD EARLY NEXT WEEK WITH DRY AND WARMER WEATHER. SHORT TERM... LATEST SATELLITE TRENDS AND SURFACE OBSERVATIONS/WEB CAMS INDICATE THAT CONVECTIVE DEVELOPMENT HAS BEEN RATHER FLAT THIS AFTERNOON. MUCH OF THE SHOWER ACTIVITY SO FAR HAS DEVELOPED WEST OF THE CREST WITH RADAR INDICATING ISOLATED SHOWERS EAST OF THE SIERRA. MODELS CONTINUE TO SHOW BEST OPPORTUNITY FOR SHOWERS AND ISOLATED THUNDER SOUTH OF HIGHWAY 50 LATE THIS AFTERNOON INTO THE EVENING. OTHERWISE ATTENTION TURNS TO DEVELOPING TROUGH ALONG THE WEST COAST FRI-SAT AS MODELS HAVE TRENDED SIGNIFICANTLY MORE AMPLIFIED. 12Z MODEL RUNS CONTINUED THE TREND OF THE PREVIOUS FEW RUNS IN DROPPING TROUGH SOUTHWARD WITH AXIS FARTHER WEST WHICH WOULD PUT THE SIERRA AND WESTERN NV IN A BETTER POSITION FOR AN ACTIVE WEATHER PATTERN. A LEAD SHORTWAVE WILL PUSH SOUTHEASTWARD ACROSS THE INTERMOUNTAIN WEST TONIGHT AND EARLY FRIDAY, WHICH WILL PUSH A COLD FRONT SOUTHWARD INTO NORTHERN CA-NORTHERN NV WHERE IT WILL STALL AND WEAKEN DURING THE DAY FRIDAY. MOISTURE AND DYNAMICS SHOULD BE SUFFICIENT LATE TONIGHT INTO FRIDAY MORNING FOR A BAND OF SHOWERS TO WORK ACROSS NORTHERN AREAS, MAINLY NORTH OF I-80 WITH SOME QPF AMOUNTS APPROACHING A COUPLE TENTHS NEAR THE OREGON BORDER VICINITY OF FRONT. OTHERWISE, SHOWERS WILL BE MORE ISOLATED WITH BREEZY CONDITIONS DEVELOPING BY FRIDAY AFTERNOON. LOCAL GUSTS TO 40 MPH ARE POSSIBLE AND AREA LAKE WATERS WILL BE CHOPPY. THE BREEZY WEST GRADIENT IS USUALLY UNFAVORABLE FOR DEEP CONVECTION AND THUS WE REMOVED THUNDERSTORM WORDING DESPITE MODEL SOUNDING INSTABILITY. THE MAIN TROUGH DROPS SOUTHWARD FRI NIGHT AND PUSHES SOUTHEASTWARD THROUGH THE AREA SATURDAY WITH A BETTER CHANCE OF MOUNTAIN SNOW AND VALLEY RAIN ALONG WITH ANOTHER BREEZY DAY SATURDAY. THE BIG QUESTION WILL BE QPF AND SNOW AMOUNTS AS MODELS STILL SHOW SOME VARIATION IN THE AMPLITUDE AND RESULTANT SPEED OF SYSTEM AS IT TRACKS THROUGH CA-NV. THE GFS/NAM ARE SLOWER OVERALL AND SHOW 1-1.5 INCHES OF QPF ALONG THE SIERRA WHICH WOULD AMOUNT TO 12-18 INCHES OF SNOW FOR THE HIGH SIERRA FROM THE TAHOE BASIN SOUTH INTO MONO COUNTY, WITH SEVERAL INCHES OF SNOW AT LAKE LEVEL AND FOR PASSES IN NORTHEAST CA. ON THE OTHER END OF THE SPECTRUM IS THE ECMWF WHICH STILL SHOWS A SIMILAR STORM TRACK ALTHOUGH FASTER AND WITH QPF ON THE ORDER OF HALF AN INCH. ALL THREE MODELS CONTINUE TO PICK UP ON A PWAT PLUME OF 1+ INCH WHICH GETS INGESTED INTO THE SYSTEM AS IT WORKS SOUTHWARD ALONG THE SIERRA. THIS WOULD TEND TO FAVOR THE WETTER SOLUTIONS. DUE TO MEDIUM CONFIDENCE IN QPF, WE HAVE INTRODUCED A FORECAST IN THE MIDDLE OF THE ROAD WHICH PUTS 6 TO 12 INCHES OF SNOW ALONG THE CREST AND A FEW INCHES DOWN TO ABOUT 5500 FEET. TRAVEL IMPACTS ARE MOST LIKELY LATE FRIDAY NIGHT AND SATURDAY MORNING. DIMINISHING SNOW RATES AND HIGH SUN ANGLE SHOULD HELP MITIGATE ROAD IMPACTS DURING THE AFTERNOON. FOR LOWER ELEVATIONS, SPILLOVER SHOULD BE DECENT BUT WILL DEPEND ON SPEED OF SYSTEM. A COOL AND DRIER NORTHERLY FLOW WILL FOLLOW SAT NIGHT INTO SUNDAY WITH TEMPERATURES THIS WEEKEND ACTUALLY STAYING BELOW NORMAL. HOHMANN LONG TERM...MONDAY THROUGH THURSDAY... MODELS STILL IN GOOD AGREEMENT WITH A MODERATE TO STRONG AMPLITUDE RIDGE BUILDING IN EARLY NEXT WEEK BRINGING DRY CONDITIONS, MOSTLY CLEAR SKIES AND AFTERNOON TEMPERATURES WARMING TO WELL ABOVE AVERAGE BY TUESDAY. HIGHS EXPECTED TO BE IN THE UPPER 70S TO MID 80S FOR WESTERN NEVADA VALLEYS AND THE UPPER 60S TO MID 70S FOR THE SIERRA VALLEYS TUESDAY AND WEDNESDAY. THE RIDGE LOOKS TO FLATTEN SOMEWHAT WEDNESDAY AND THURSDAY AS ENERGY MOVES THROUGH THE PACIFIC NORTHWEST. THIS WILL BRING SOME INCREASE IN AFTERNOON AND EVENING ZEPHYR-LIKE BREEZES ALONG WITH A SLIGHT COOL DOWN BY THURSDAY (ALTHOUGH HIGHS WILL REMAIN CONSIDERABLY ABOVE AVERAGE). SNYDER AVIATION... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED INTO THIS EVENING, FOCUSED SOUTH OF HIGHWAY 50. LOCAL HIGHER TERRAIN OBSCURATION IN HEAVIER SHOWERS AS WELL AS THUNDERSTORMS, WITH SMALL HAIL AND OUTFLOW GUSTS TO 30 KTS POSSIBLE IN ALL STORMS. NORTH OF I-80, DRIER AIR HAS WORKED IN WITH ONLY ISOLATED SHOWERS EXPECTED. FOR TONIGHT SOME SHOWERS TO REDEVELOP AFTER 11 PM (06Z FRIDAY) WITH OCCASIONAL MVFR CIGS POSSIBLE, MAINLY NORTH OF I-80. A WETTER LATE FRIDAY NIGHT AND SATURDAY MORNING IS STILL ON TRACK. WIDESPREAD TERRAIN OBSCURATION FOR SIERRA AND NORTHEAST CALIFORNIA CAN BE EXPECTED, WITH SUB-LANDING MINIMUMS POSSIBLE FOR KTRK AND LIKELY FOR KTVL THROUGH SATURDAY MORNING. ALSO, MINOR ACCUMULATIONS POSSIBLE ON RUNWAYS FOR KTRK/KTVL. OUT INTO WESTERN NEVADA, RAIN IS EXPECTED FOR LOWER VALLEY TERMINALS WITH THE MAIN IMPACTS BEING HIGHER TERRAIN OBSCURATION, PERIODIC MVFR CIGS AND LEE OF THE SIERRA TURBULENCE. SNYDER && .REV WATCHES/WARNINGS/ADVISORIES... NV...LAKE WIND ADVISORY FROM 11 AM TO 8 PM PDT FRIDAY FOR PYRAMID LAKE IN NVZ004. LAKE WIND ADVISORY FROM 11 AM TO 8 PM PDT FRIDAY FOR LAKE TAHOE IN NVZ002. CA...LAKE WIND ADVISORY FROM 11 AM TO 8 PM PDT FRIDAY FOR LAKE TAHOE IN CAZ072. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
939 PM MDT SAT APR 25 2015 .UPDATE... ISSUED AT 556 PM MDT SAT APR 25 2015 FEW ADJUSTMENTS TO POP GRIDS AS SHOWERS CONTINUE TO EXPAND IN COVERAGE ACROSS THE WEST SLOPE. EXPECT THE SHOWERS AND THUNDERSTORMS TO CONTINUE THROUGH ABOUT 2 AM...BEFORE DIMINISHING IN AREAL COVERAGE AS WE PUSH TOWARD SUNRISE. HRRR AND NAM BOTH LEANING TOWARD THIS SOLUTION. HOWEVER...ANOTHER ROUND STILL IN STORE FOR MOST OF THE FORECAST AREA LATER SUNDAY AS THE LOW PASSES TO OUR SOUTH AND HEADS EAST TO ALBUQUERQUE SUNDAY AFTERNOON. && .SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT) ISSUED AT 343 PM MDT SAT APR 25 2015 DAYTIME HEATING COMBINED WITH 500 TO 1000J OF CAPE THIS AFTERNOON IS PRODUCING THUNDERSTORMS IN EASTERN UTAH AND WESTERN COLORADO IN PARTLY CLOUDY SKIES AHEAD OF THE NEXT CLOUD SHIELD CURRENTLY OVER UTAH. PERIODS OF MODERATE TO HEAVY RAIN ARE EXPECTED WITH THESE THUNDERSTORMS...AS WELL AS SMALL HAIL...FREQUENT LIGHTNING...AND GUSTY WINDS. THE APPROACHING TROUGH AND COLD FRONT WILL INCREASE SOUTHWESTERLY WINDS AND PRECIPITATION THIS EVENING. BY MIDNIGHT TONIGHT THE FRONT WILL BE REACHING CENTRAL UTAH AND THEN EASTERN UTAH BY THE EARLY MORNING HOURS. EXPECT PERIODS OF SHOWERS AND THUNDERSTORMS THROUGHOUT THE NIGHT. SOUTHERN PORTION OF THE SPLITTING TROUGH FORMS A CLOSED LOW JUST SOUTH OF THE FOUR CORNERS BY MIDDAY SUNDAY WITH PRECIPITATION EXPECTED TO BE WIDESPREAD ACROSS THE FORECAST AREA. SOUTHERLY FLOW AT MOUNTAINTOP LEVEL SUNDAY MORNING BECOMES EAST TO NORTHEAST SUNDAY AFTERNOON AS THE 700 MB LOW CONSOLIDATES ALONG THE CO/NM BORDER. AREA OF UPPER DIVERGENCE DEVELOPS OVER THE CENTRAL AREAS AS THE WRAPAROUND FLOW NORTH OF THE LOW ENCOUNTERS THE SPLIT TROUGH AXIS PUSHING IN FROM UT. THIS COUPLET OF UPPER DIVERGENCE AND LOW LEVEL MOISTURE CONVERGENCE SHOULD AID PRECIPITATION. Q-G FIELDS SHOW INCREASING SUBSIDENCE SUNDAY NIGHT BUT MOIST LOW LEVEL NORTH TO NORTHEAST FLOW SHOULD KEEP SOME SNOW GOING ON FAVORED SLOPES SUNDAY NIGHT. UPGRADED THE WINTER STORM WATCH TO A LATE-SEASON IMPACTED-BASED WINTER STORM WARNING FOR ELEVATIONS ABOVE 9000 FT BEGINNING AT MIDNIGHT TONIGHT FOR 5-10 INCHES OF SNOW. MOUNTAIN PASSES THE MOST AFFECTED. ADDED THE ABAJO/LA SAL MTNS IN SE UT TO THE WARNING FOR 4-8 INCHES. ALSO PUT THE FLAT TOPS AND GORE/ELK MTNS IN A WINTER ADVISORY ABOVE 9000 FEET. LIKELY TO SEE SNOW BELOW 9000 FEET AT TIMES BUT ACCUMULATIONS AND IMPACT WILL BE LESS. COOLER AIR COULD PUSH LOW TEMPS DOWN NEAR FREEZING IN THE CORTEZ AND DURANGO AREAS LATE SUNDAY NIGHT FOR A CONCERN TO ORCHARD AND VINEYARDS IN THOSE AREAS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 343 PM MDT SAT APR 25 2015 MODELS ARE CONSISTENT MOVING THE CLOSED SOUTHWEST LOW ACROSS NRN TX AND OKLA MONDAY AND MONDAY NIGHT. MOISTURE IN THE NORTHEAST FLOW WRAPPING BACK AROUND THE LOW WILL KEEP A CHANCE OF SHOWERS MAINLY OVER THE WRN CO MTNS MONDAY AS DRIER AIR SLOWLY WORKS IN FROM THE WEST. A POSITIVE-TILTED UPPER RIDGE PUSHES INTO THE GREAT BASIN TUE AND OVERHEAD ON WED. THIS RIDGE THEN BECOMES THE DOMINANT WEATHER FEATURE UNTIL FRI...WHEN A DEVELOPING WEST COAST TROUGH SHIFTS THE RIDGE EASTWARD. A WARMING TREND WILL PUSH DAYTIME TEMPS ABOVE NORMAL WED-FRI. AS THE RIDGE SHIFTS EAST...SOUTHWEST WINDS SHOULD PICK UP THU AND FRI IN THE FAVORED AREAS OF ERN UT AND NW CO. LINGERING MOISTURE AND AFTERNOON HEATING WILL KEEP A LOW CHANCE OF SHOWERS OVER THE MTNS TUE-THU...BUT MOST AREAS SHOULD BE DRY. THE CHANCE OF MTN SHOWERS BEGINS TO INCREASE FRI AND SAT AS THE WEST COAST TROUGH DEVELOPS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 934 PM MDT SAT APR 25 2015 FLIGHT CONDITIONS WILL CONTINUE IN THE MVFR AND IFR RANGE AT MOST TAF SITES THROUGH SUNDAY. A STRENGTHENING STORM CENTERED OVER WESTERN AZ WILL CONTINUE MOVING EAST TONIGHT THROUGH SUNDAY AND REACH NEW MEXICO BY SUNDAY AFTERNOON. WIDESPREAD RAIN AND SNOW SHOWERS ALONG WITH ISOLATED THUNDERSTORMS WILL CONTINUE ACROSS ALL OF EASTERN UTAH AND WESTERN COLORADO THROUGH THIS PERIOD. EXPECT SNOW LEVELS TO DROP AS LOW AS 7500 FEET AT TIMES. MOUNTAINS WILL BE OBSCURED THROUGH THE PERIOD. THERE WILL BE BRIEF OPEN VFR WINDOWS BETWEEN WAVES OF RAIN AND SNOW. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...WINTER WEATHER ADVISORY UNTIL 9 AM MDT MONDAY FOR COZ010-013. WINTER STORM WARNING UNTIL 9 AM MDT MONDAY FOR COZ009-012-018- 019. UT...WINTER STORM WARNING UNTIL 9 PM MDT SUNDAY FOR UTZ028. && $$ UPDATE...JDC SHORT TERM...JAM/JAD LONG TERM...JAD AVIATION...CC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
559 PM MDT SAT APR 25 2015 .UPDATE... ISSUED AT 556 PM MDT SAT APR 25 2015 FEW ADJUSTMENTS TO POP GRIDS AS SHOWERS CONTINUE TO EXPAND IN COVERAGE ACROSS THE WEST SLOPE. EXPECT THE SHOWERS AND THUNDERSTORMS TO CONTINUE THROUGH ABOUT 2 AM...BEFORE DIMINISHING IN AREAL COVERAGE AS WE PUSH TOWARD SUNRISE. HRRR AND NAM BOTH LEANING TOWARD THIS SOLUTION. HOWEVER...ANOTHER ROUND STILL IN STORE FOR MOST OF THE FORECAST AREA LATER SUNDAY AS THE LOW PASSES TO OUR SOUTH AND HEADS EAST TO ALBUQUERQUE SUNDAY AFTERNOON. && .SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT) ISSUED AT 343 PM MDT SAT APR 25 2015 DAYTIME HEATING COMBINED WITH 500 TO 1000J OF CAPE THIS AFTERNOON IS PRODUCING THUNDERSTORMS IN EASTERN UTAH AND WESTERN COLORADO IN PARTLY CLOUDY SKIES AHEAD OF THE NEXT CLOUD SHIELD CURRENTLY OVER UTAH. PERIODS OF MODERATE TO HEAVY RAIN ARE EXPECTED WITH THESE THUNDERSTORMS...AS WELL AS SMALL HAIL...FREQUENT LIGHTNING...AND GUSTY WINDS. THE APPROACHING TROUGH AND COLD FRONT WILL INCREASE SOUTHWESTERLY WINDS AND PRECIPITATION THIS EVENING. BY MIDNIGHT TONIGHT THE FRONT WILL BE REACHING CENTRAL UTAH AND THEN EASTERN UTAH BY THE EARLY MORNING HOURS. EXPECT PERIODS OF SHOWERS AND THUNDERSTORMS THROUGHOUT THE NIGHT. SOUTHERN PORTION OF THE SPLITTING TROUGH FORMS A CLOSED LOW JUST SOUTH OF THE FOUR CORNERS BY MIDDAY SUNDAY WITH PRECIPITATION EXPECTED TO BE WIDESPREAD ACROSS THE FORECAST AREA. SOUTHERLY FLOW AT MOUNTAINTOP LEVEL SUNDAY MORNING BECOMES EAST TO NORTHEAST SUNDAY AFTERNOON AS THE 700 MB LOW CONSOLIDATES ALONG THE CO/NM BORDER. AREA OF UPPER DIVERGENCE DEVELOPS OVER THE CENTRAL AREAS AS THE WRAPAROUND FLOW NORTH OF THE LOW ENCOUNTERS THE SPLIT TROUGH AXIS PUSHING IN FROM UT. THIS COUPLET OF UPPER DIVERGENCE AND LOW LEVEL MOISTURE CONVERGENCE SHOULD AID PRECIPITATION. Q-G FIELDS SHOW INCREASING SUBSIDENCE SUNDAY NIGHT BUT MOIST LOW LEVEL NORTH TO NORTHEAST FLOW SHOULD KEEP SOME SNOW GOING ON FAVORED SLOPES SUNDAY NIGHT. UPGRADED THE WINTER STORM WATCH TO A LATE-SEASON IMPACTED-BASED WINTER STORM WARNING FOR ELEVATIONS ABOVE 9000 FT BEGINNING AT MIDNIGHT TONIGHT FOR 5-10 INCHES OF SNOW. MOUNTAIN PASSES THE MOST AFFECTED. ADDED THE ABAJO/LA SAL MTNS IN SE UT TO THE WARNING FOR 4-8 INCHES. ALSO PUT THE FLAT TOPS AND GORE/ELK MTNS IN A WINTER ADVISORY ABOVE 9000 FEET. LIKELY TO SEE SNOW BELOW 9000 FEET AT TIMES BUT ACCUMULATIONS AND IMPACT WILL BE LESS. COOLER AIR COULD PUSH LOW TEMPS DOWN NEAR FREEZING IN THE CORTEZ AND DURANGO AREAS LATE SUNDAY NIGHT FOR A CONCERN TO ORCHARD AND VINEYARDS IN THOSE AREAS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 343 PM MDT SAT APR 25 2015 MODELS ARE CONSISTENT MOVING THE CLOSED SOUTHWEST LOW ACROSS NRN TX AND OKLA MONDAY AND MONDAY NIGHT. MOISTURE IN THE NORTHEAST FLOW WRAPPING BACK AROUND THE LOW WILL KEEP A CHANCE OF SHOWERS MAINLY OVER THE WRN CO MTNS MONDAY AS DRIER AIR SLOWLY WORKS IN FROM THE WEST. A POSITIVE-TILTED UPPER RIDGE PUSHES INTO THE GREAT BASIN TUE AND OVERHEAD ON WED. THIS RIDGE THEN BECOMES THE DOMINANT WEATHER FEATURE UNTIL FRI...WHEN A DEVELOPING WEST COAST TROUGH SHIFTS THE RIDGE EASTWARD. A WARMING TREND WILL PUSH DAYTIME TEMPS ABOVE NORMAL WED-FRI. AS THE RIDGE SHIFTS EAST...SOUTHWEST WINDS SHOULD PICK UP THU AND FRI IN THE FAVORED AREAS OF ERN UT AND NW CO. LINGERING MOISTURE AND AFTERNOON HEATING WILL KEEP A LOW CHANCE OF SHOWERS OVER THE MTNS TUE-THU...BUT MOST AREAS SHOULD BE DRY. THE CHANCE OF MTN SHOWERS BEGINS TO INCREASE FRI AND SAT AS THE WEST COAST TROUGH DEVELOPS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 506 PM MDT SAT APR 25 2015 AN UPPER LEVEL LOW PRESSURE SYSTEM WILL CONTINUE TO GAIN STRENGTH OVER NORTHERN ARIZONA TONIGHT AND EARLY SUNDAY...THEN LIFT EAST ACROSS NEW MEXICO BY SUNDAY AFTERNOON. WIDESPREAD RAIN AND SNOW SHOWERS ALONG WITH ISOLATED THUNDERSTORMS WILL CONTINUE ACROSS ALL OF EASTERN UTAH AND WESTERN COLORADO THROUGH THIS PERIOD. EXPECT SNOW LEVELS TO DROP AS LOW AS 7500 FEET AT TIMES. MOUNTAINS WILL BE OBSCURED THROUGH THE PERIOD WITH WIDESPREAD IFR AND MVFR CIGS EXPECTED WITH ALL TERMINAL SITES IMPACTED FOR SEVERAL HOURS. THERE WILL BE OPEN VFR WINDOWS BETWEEN WAVES OF RAIN AND SNOW. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM MDT MONDAY FOR COZ010-013. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 9 AM MDT MONDAY FOR COZ009-012-018-019. UT...WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 9 PM MDT SUNDAY FOR UTZ028. && $$ UPDATE...JDC SHORT TERM...JAM/JAD LONG TERM...JAD AVIATION...JDC
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
938 PM EDT SAT APR 25 2015 .SYNOPSIS... LOW PRESSURE NEAR THE TENNESSEE VALLEY WILL PROGRESS TO THE EAST, PASSING OFF THE NORTH CAROLINA COAST LATE TONIGHT. HIGH PRESSURE IS THEN FORECAST TO BUILD GRADUALLY INTO OUR REGION DURING THE EARLY AND MIDDLE PARTS OF THE NEW WEEK. ANOTHER AREA OF LOW PRESSURE IS EXPECTED TO PASS OFF THE NORTH CAROLINA COAST AND MOVE OUT TO SEA ON THURSDAY. A COLD FRONT IS ANTICIPATED TO PASS THROUGH OUR REGION AT THAT TIME, THEN HIGH PRESSURE FOLLOWS FOR FRIDAY AND SATURDAY. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... LOW PRESSURE OVER KENTUCKY THIS EVENING WILL TRACK EASTWARD OVERNIGHT. MEANWHILE A FRONTAL BOUNDARY IS STALLED WELL TO OUR SOUTH. AN UPPER-LEVEL TROUGH IN THE NORTHEAST BENDS BACK INTO THE OHIO VALLEY WHERE AN UPPER LOW IS LOCATED. THIS FEATURE IS TENDING TO SHEAR SOME EASTWARD, HOWEVER THERE IS A DECENT AMOUNT OF PVA TO PORTIONS OF THE MID ATLANTIC. THE ASSOCIATED LIFT WITH THE SHORT WAVE ENERGY COMBINED WITH WAA/ISENTROPIC LIFT IS GENERATING AN AREA OF MAINLY LIGHT RAIN. THIS IS MOVING ACROSS PORTIONS OF OUR EASTERN MARYLAND AND DELAWARE ZONES. THERE IS DRIER AIR FARTHER NORTH AND WITH SOME CONFLUENCE THE RAIN IS HAVING A TOUGH TIME EDGING NORTHWARD. IT DOES APPEAR IT COULD LIFT A BIT FARTHER NORTH PER THE RAP, HRRR AND NAM, BUT PROBABLY NOT AS FAR NORTH AS THE GFS/ECMWF SHOW. THE POPS WERE ADJUSTED SOME AND WE MAINTAINED A NARROW AREA OF LIKELY TO CATEGORICAL ACROSS OUR FAR SOUTHERN DELMARVA AREA. THE DRY LOW-LEVEL AIR EARLIER MAY HAVE RESULTED IN SOME ICE PELLETS AT THE ONSET. OTHERWISE, MID TO HIGH CLOUDS WILL STREAM ACROSS MUCH OF THE AREA NORTH OF THE LIGHT RAIN SHIELD. IT IS UP NORTH WHERE THE CLOUDINESS SHOULD BE THE HIGHEST AND NOT AS THICK, ALLOWING TEMPERATURES TO POSSIBLY FALL A LITTLE FASTER WITH LIGHT WINDS. THIS MAY ALLOW FOR SOME FROST TO FORM LATE, MAINLY FOR AREAS NORTH OF INTERSTATE 78. A FROST ADVISORY THEREFORE REMAINS IN EFFECT FOR LATE TONIGHT AND EARLY SUNDAY MORNING FOR PORTIONS OF NORTHERN NEW JERSEY AND THE ADJACENT AREAS OF EASTERN PENNSYLVANIA. THE HOURLY GRIDS WERE ADJUSTED WITH THE LATEST OBSERVATIONS, AND THEN THE LAMP/LAV GUIDANCE WAS BLENDED IN. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... LOW PRESSURE OFF THE NORTH CAROLINA COAST WILL ADVANCE FARTHER EAST AND OUT TO SEA THROUGH THE COURSE OF THE DAY. THROUGH THE MORNING, THOUGH, THICKER CLOUDS AND A CHANCE FOR SOME LIGHT RAIN WILL REMAIN FOR OUR SOUTHERN ZONES AS THIS SYSTEM PULLS AWAY. THE REST OF THE FORECAST AREA CAN EXPECT MORE OF A PARTLY CLOUDY DAY WITH SOME LIGHT NORTHERLY WINDS AND TEMPERATURES ONLY SLIGHTLY BELOW LATE APRIL AVERAGES, MILDER THAN THE LAST FEW DAYS. MAXIMUM TEMPERATURES ARE EXPECTED TO REACH MOSTLY THE LOWER TO PERHAPS MIDDLE 60S, WITH SOME COOLER 50S ALONG THE COASTS OF NEW JERSEY AND DELAWARE AND INTO THE HIGHER TERRAIN OF THE POCONOS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... A PARTLY CLOUDY SKY IS EXPECTED FOR SUNDAY NIGHT. TEMPERATURES ARE FORECAST TO DROP INTO THE UPPER 30S TO MIDDLE 40S RANGE IN MUCH OF OUR REGION BY DAYBREAK ON MONDAY. SOME LOCATIONS IN NORTHERN NEW JERSEY COULD FALL INTO THE MIDDLE 30S WITH PATCHY FROST POSSIBLE. WE SHOULD REMAIN UNDER THE INFLUENCE OF A MID LEVEL LOW OFF NOVA SCOTIA DURING THE PERIOD FROM SUNDAY NIGHT INTO TUESDAY NIGHT. A MID LEVEL TROUGH ROTATING AROUND THE LOW IS FORECAST TO PASS OVERHEAD ON MONDAY. THE TROUGH IS EXPECTED TO BRING CLOUDS TO OUR REGION FOR MONDAY INTO MONDAY NIGHT. ALSO, THERE IS A CHANCE OF SHOWERS ON MONDAY INTO MONDAY EVENING. ANY RAIN SHOWERS ARE EXPECTED TO BE LIGHT BEING THAT THE AIR MASS IS ANTICIPATED TO BE QUITE DRY AND A FAIR AMOUNT OF EVAPORATION IS LIKELY. A WEAK MID LEVEL RIDGE IS FORECAST TO APPROACH FROM THE WEST AND NORTHWEST ON TUESDAY AS THE MID LEVEL LOW MOVES FARTHER OUT TO SEA. THE RIDGE SHOULD PASS OVERHEAD ON WEDNESDAY. BOTH DAYS ARE EXPECTED TO BE DRY. THE MODELS CONTINUE TO DIFFER ON THE HANDLING OF THE MID LEVEL LOW THAT IS ANTICIPATED TO DROP SOUTHEASTWARD ACROSS THE EASTERN STATES LATE IN THE WEEK. ALSO, THERE IS DISAGREEMENT IN THE DEVELOPMENT AND TRACK OF THE ASSOCIATED SURFACE FEATURES. WE WILL CONTINUE TO FAVOR THE ECMWF SOLUTION WITH A COASTAL LOW PASSING OFF THE NORTH CAROLINA COAST. IT CONTINUES TO APPEAR AS THOUGH MOST OF ITS IMPACT WILL REMAIN TO OUR SOUTH AND EAST. WE SHOULD BE INFLUENCED BY A COLD FRONT DROPPING THROUGH OUR REGION ON THURSDAY AND WE WILL MENTION SOME CLOUDS AND A CHANCE OF SHOWERS FOR THAT PERIOD OF TIME. SURFACE HIGH PRESSURE FROM THE WEST AND DRY WEATHER ARE ANTICIPATED TO FOLLOW FOR FRIDAY AND SATURDAY. A SHORT WAVE TROUGH IN THE NORTHWESTERLY MID LEVEL FLOW MAY PASS OVERHEAD ON SATURDAY. IT WILL HAVE LIMITED MOISTURE ASSOCIATED WITH IT AND WE ARE EXPECTING NO MORE THAN SCATTERED CLOUDS AT THIS TIME. DAYTIME TEMPERATURES ARE ANTICIPATED TO BE BELOW NORMAL FOR MONDAY AND TUESDAY. THEY ARE EXPECTED TO BE NEAR NORMAL FOR WEDNESDAY, THURSDAY AND FRIDAY, AND THEY MAY GO A BIT ABOVE NORMAL FOR SATURDAY. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REST OF TONIGHT...VFR WITH A CEILING AT OR ABOVE 8000 FEET /LOWEST SOUTH/. SOUTHWEST WINDS AROUND 5 KNOTS BECOMING MOSTLY LIGHT AND VARIABLE, THEN BECOMING NORTHERLY 5 TO 8 KNOTS TOWARD DAYBREAK. SOME LIGHT RAIN MAY NEAR KMIV AND KACY OVERNIGHT FOR A TIME. SUNDAY...VFR. SOME CLOUD BASES /SCATTERED/ DEVELOPING AT 5000 FEET, AND A CEILING AT OR ABOVE 10000 FEET FOR SOME AREAS ESPECIALLY IN THE MORNING. NORTH TO NORTHEAST WINDS MAINLY 5-10 KNOTS, BECOMING NORTHWEST TOWARD LATE AFTERNOON. OUTLOOK... SUNDAY NIGHT...MAINLY VFR. MONDAY...MAINLY VFR WITH A CHANCE OF SHOWERS. MONDAY NIGHT THROUGH WEDNESDAY NIGHT...MAINLY VFR. THURSDAY...MAINLY VFR WITH A CHANCE OF SHOWERS. && .MARINE... SUB-ADVISORY CONDITIONS WILL CONTINUE FOR THE COASTAL WATERS AND FOR DELAWARE BAY. A LOW PRESSURE SYSTEM IS EXPECTED TO PASS TO THE SOUTH OF THE REGION DURING THE OVERNIGHT TO EARLY SUNDAY, BUT OTHER THAN SOME LIGHT RAIN AND A FEW WIND GUSTS TO 20 KNOTS FOR THE SOUTHERN COASTAL WATERS, LITTLE IMPACT IS ANTICIPATED. OUTLOOK... SUNDAY NIGHT AND MONDAY...NO MARINE HEADLINES ARE ANTICIPATED. MONDAY NIGHT...A NORTHWEST WIND MAY GUST AROUND 25 KNOTS. TUESDAY THROUGH THURSDAY...NO MARINE HEADLINES ARE ANTICIPATED. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...FROST ADVISORY FROM 3 AM TO 8 AM EDT SUNDAY FOR PAZ061-062-105. NJ...FROST ADVISORY FROM 3 AM TO 8 AM EDT SUNDAY FOR NJZ001-007>010. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...GORSE/IOVINO NEAR TERM...GORSE/KLINE SHORT TERM...KLINE LONG TERM...IOVINO AVIATION...GORSE/IOVINO MARINE...IOVINO/KLINE
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
828 PM EDT SAT APR 25 2015 .UPDATE...STORMS CONTINUE OVER SE GA IN AREA OF STRONG SHEAR ASSOCIATED WITH RIGHT REAR QUAD OF UPPER JET. HRRR MODEL SHOWS ACTIVITY MOVING ACROSS SE GA UNTIL AROUND MIDNIGHT BEFORE MOVING OFFSHORE. EXPECT STRONG TO SEVERE STORMS POSSIBLE OVER SE GA WITH SVR TSTM WATCH IN EFFECT UNTIL 11 PM. MAIN AXIS OF MOISTURE AND STORMS WILL SHIFT S INTO NE FL ON SUNDAY. && .AVIATION...EXPECT VFR CONDITIONS TO PREVAIL TONIGHT AND MOST OF SUNDAY. THUNDERSTORMS LIKELY TO AFFECT SSI BETWEEN 02Z AND 04Z THIS EVENING. HAVE VCTS IN TAFS AGAIN FOR SUNDAY AFTERNOON FOR FL TAFS. && .MARINE...EXPECT STORMS TO MOVE INTO THE GA WATERS AROUND MIDNIGHT. SW WINDS WILL INCREASE TO ADVISORY CONDITIONS OFFSHORE AND CAUTION LEVELS NEAR SHORE TONIGHT. RIP CURRENTS: LOW RISK ON SUNDAY WITH OFFSHORE WINDS. && .PRELIMINARY POINT TEMPS/POPS... AMG 69 89 64 79 / 70 20 10 0 SSI 70 86 66 74 / 60 20 10 10 JAX 72 90 68 80 / 40 30 20 30 SGJ 71 84 70 79 / 40 30 30 30 GNV 72 86 71 84 / 20 30 30 40 OCF 72 87 70 84 / 10 40 40 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR WATERS FROM ALTAMAHA SOUND GA TO FERNANDINA BEACH FL FROM 20 TO 60 NM- WATERS FROM FERNANDINA BEACH TO ST. AUGUSTINE FL FROM 20 TO 60 NM-WATERS FROM ST. AUGUSTINE TO FLAGLER BEACH FL FROM 20 TO 60 NM. && $$ ZIBURA/PETERSON/WALSH
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
400 PM EDT FRI APR 24 2015 .SYNOPSIS... 19Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS DEEP TROUGHING THROUGH THE DESERT SOUTHWEST INTO NORTHERN MEXICO...FOLLOWED DOWNSTREAM BY AMPLIFIED RIDGING ACROSS THE GULF OF MEXICO AND DEEP SOUTH STATES. MOIST SUBTROPICAL JET IS RIDING NORTHWARD BETWEEN THESE TWO FEATURES OVER THE SOUTHERN PLAINS BEFORE TURNING EASTWARD ACROSS THE SOUTHEAST CONUS. THE FLORIDA PENINSULA RESIDES ON THE EASTERN PERIPHERY OF THE UPPER RIDGE WHERE OUR DEEP LAYER WINDS PER 12Z KTBW SOUNDING PROFILE WERE FROM THE NORTHWEST. SOUNDING DID SHOW A BIT OF A SUBSIDENCE INVERSION ASSOCIATED WITH THE UPPER RIDGE AROUND 700MB...WITH A MOIST PROFILE BELOW THIS LEVEL TO THE SURFACE. AT THE SURFACE... 1020MB CONTINENTAL HIGH PRESSURE RIDGING DOWN INTO THE SOUTHEAST CONUS HAS PUSHED A WEAK FRONTAL BOUNDARY DOWN INTO THE CENTRAL FLORIDA PENINSULA. CONTINUE TO SEE A BIG GRADIENT IN SURFACE DEWPOINTS ACROSS THIS BOUNDARY WITH LOWER 70S SOUTH OF THE I-4 CORRIDOR...AND THEN QUICKLY DROPPING TO READINGS IN THE 50S AROUND OCALA. THE GENERAL LOCATION OF THE BOUNDARY CAN ALSO BE EASILY SEEN WITH VISIBLE SATELLITE IMAGERY...WHERE A DEFINED CUMULUS DEVELOPMENT CUTOFF IS LOCATED VERY NEAR I-4. SOUTH OF THIS LINE...DIURNAL HEATING WORKED WITH THE GREATER BOUNDARY LAYER MOISTURE TO FORM THE SCT-BKN CUMULUS FIELD...WHILE NORTH THE MOISTURE IS SIMPLY NOT IN PLACE TO EFFICIENTLY PRODUCE MUCH IN THE WAY OF CLOUDS. REGIONAL RADARS SHOW A FEW SHOWERS TRYING TO DEVELOP ALONG THE SEA BREEZE JUST EAST OF FORT MYERS DOWN TOWARD AREAS JUST EAST OF NAPLES. LAST FEW HRRR RUNS SUGGEST WE WILL SEE SOME ADDITIONAL DEVELOPMENT UP INTO OUR SOUTH-CENTRAL ZONES INTO THE EARLY EVENING AS THE SEA-BREEZE CONTINUES TO ATTEMPT MIGRATING INLAND...HOWEVER ONLY EXPECTING ISOLATED TO WIDELY SCT COVERAGE. && .SHORT TERM (REST OF TODAY THROUGH SATURDAY... REST OF TODAY... THE FORECAST WILL BE SPLIT NORTH TO SOUTH BY THE BOUNDARY NEAR THE I-4 CORRIDOR. NORTH OF THIS BOUNDARY...THE LACK OF BL MOISTURE MAKES INSTABILITY REALLY LACKING AND DO NOT HAVE ANY THUNDERSTORM MENTION IN THE FORECAST. AS MENTIONED ABOVE IN THE SYNOPSIS...SOUTH OF THE I-4 CORRIDOR...THE SEA- BREEZE SHOULD PROVIDE JUST ENOUGH FOCUS...AND THE COLUMN IS JUST CONDUCIVE ENOUGH TO POP A FEW SCT LATE DAY SHOWERS/STORMS. 20% POPS EXTEND AS FAR NORTH AS POLK COUNTY ALONG THE SOUTHERN EDGE OF THE BOUNDARY...AND THEN HAVE CHANCE 30% POPS OVER THE SOUTHERN ZONES (MAINLY AWAY FROM THE BEACHES). TONIGHT... ANY ISOLATED EVENING STORMS WILL DISSIPATE QUICKLY WITH THE LOSS OF DIURNAL HEATING. UPPER RIDGE AXIS WILL BE SHIFTING EASTWARD AND BE CENTERED OVER THE EASTERN GULF OF MEXICO BY EARLY SATURDAY MORNING. SEVERAL UPPER LEVEL SHORTWAVE FEATURES WILL COMBINE WITH EFFICIENT WAA REGIME TO RESULT IN AN ACTIVE CONVECTION NIGHT ACROSS THE LOWER MS VALLEY OVER TO AL/GA. HOWEVER...HIGH PRESSURE SHIFTING OFF THE EASTERN SEABOARD WILL RIDGE BACK TO THE SOUTHWEST OVER OUR HEADS. THIS STACKED RIDGING REGIME SHOULD BE PLENTY TO PROTECT OUR ZONES AND KEEP THIS INCLEMENT WEATHER WELL TO OUR NORTH AND NORTHWEST THROUGH THE OVERNIGHT. SATURDAY... STRONG SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW WILL EJECT OUT OF THE CENTRAL PLAINS INTO THE OHIO/TN VALLEYS...WHILE A SERIES OF WEAKER IMPULSES RIDE EASTWARD ALONG THE NORTH-CENTRAL GULF COAST. THE MOVEMENT OF THESE MASS FIELDS WILL RESULT IN A DE- AMPLIFICATION OF THE UPPER RIDGE OVER OUR REGION THROUGH THE DAY. WARM FRONTAL BOUNDARY WILL BE ALIGNED TO THE NORTH OF THE I-10 CORRIDOR WITH QUITE A BIT OF ONGOING SHOWER AND STORM ACTIVITY FROM THE FLORIDA PANHANDLE TO AL/GA. THE QUESTION FOR OUR FORECAST WILL BE HOW THE WEST COAST SEA-BREEZE BEHAVES THROUGH THE DAY. GENERALLY SPEAKING...THE GOOD SYNOPTIC SETUP FOR LIFT WILL REMAIN TO OUR NORTH TOMORROW...BUT WE WILL HAVE THE SEA-BREEZE TO PROVIDE AT LEAST SOME FOCUS. WIND FIELDS EVOLVE FAVORABLY TOWARD ORGANIZED CONVECTIVE POTENTIAL DURING THE DAY (ESPECIALLY NORTH OF TAMPA BAY)...WITH 0-6KM SHEAR VALUES ELEVATING TO BETWEEN 40-45 KNOTS OVER OUR NORTHERN ZONES. THESE VALUES...ALTHOUGH NOT EXTREME...ARE CAPABLE OF SUSTAINING ORGANIZED CONVECTION. HERE IS THE PROBLEM FOR OUR AREA...THE 1000-700MB FLOW TOMORROW IS FROM THE W/SW AT 15-25 KNOTS. FIRST OF ALL...THIS WILL KEEP THE WEST COAST SEA- BREEZE FAIRLY WEAK AND DISORGANIZED. SECOND...THE BOUNDARY WILL VERY QUICKLY TRANSLATE INLAND. WITH THIS IN MIND...CURRENT THINKING IS THAT THE BEST CHANCES FOR AFTERNOON THUNDER WOULD BE OVER TOWARD THE FLORIDA EAST COAST...WHERE SEA- BREEZE COLLISION WILL TAKE PLACE. IT IS A TOUGH CALL SINCE ANY CONVECTION THAT DOES DEVELOP WILL BE MOVING QUICKLY AND COULD TRANSLATE STRONGER WIND MOMENTUM TO THE GROUND. JUST UNSURE THAT MUCH CONVECTION WILL EVEN TAKE PLACE OVER OUR ZONES IN THE FIRST PLACE. BETTER CHANCES FOR THE STORMS SHOULD STAY MAINLY EAST AND NORTH OF OUR ZONES. && .LONG TERM (SUNDAY THROUGH NEXT FRIDAY)... SUN - A PACIFIC NORTHWEST SHORT WAVE TROUGH DROPS INTO THE FOUR CORNERS AREA AND CUTS-OFF AS A TROUGH FROM THE LOWER GREAT LAKES TO THE MID- ATLANTIC STATES SLIDES OUT OVER THE ATLANTIC...WITH NEARLY ZONAL/FLAT RIDGING ACROSS THE GULF REGION. A WEAK FRONTAL BOUNDARY OVER THE GULF COASTAL STATES SHIFTS DOWN INTO FL WITH AN ATLANTIC SURFACE RIDGE... INITIALLY ACROSS FL...SLIPPING SOUTH OF THE STATE. MON -TUE - THE FOUR CORNERS LOW OPENS AS IT TRACKS TO THE EASTERN PLAINS...WITH TROUGHINESS DROPPING INTO THE WEST GULF AS RIDGING IN THE EAST GULF SLIDES ACROSS FL. THE FRONTAL BOUNDARY ACROSS THE STATE LIFTS NORTH WITH A LOW FORMING ON THE WESTERN PORTION...OVER THE CENTRAL GULF OR GULF COAST. WED-THU - THE EASTERN PLAINS TROUGH MOVES TO THE EASTERN SEABOARD...AS A TROUGH OR CLOSED LOW...WITH SOUTHWESTERLY FLOW ALOFT STREAMING SOME DEEPER MOISTURE ACROSS THE GULF AND MUCH OF FL. THE SURFACE LOW TREKS EAST OR EAST-NORTHEAST WITH A TRAILING COLD FRONT SWINGING INTO FL. FRI - THE UPPER TROUGH/LOW EXITS THE EASTERN SEABOARD AS UPPER RIDGING BUILDS OVER THE NATIONS/S MID-SECTION. SURFACE HIGH PRESSURE SETTLES IN ACROSS THE PLAINS OR THE MISSISSIPPI VALLEY WITH THE FL BOUNDARY GETTING PUSHED TO OR OFFSHORE FAR SOUTH FL. SENSIBLE WEATHER AND FORECAST - THE UP-COMING WEEK IS A COMPLEX PATTERN WITH THE GFS/ECMWF/CMC MODELS NOT IN VERY GOOD AGREEMENT AND PERHAPS OVERDOING SOME OF THE SMALLER DETAILS. IN ANY CASE...EXPECT MOIST TO WET CONDITIONS THROUGH MOST OF THE PERIOD WITH SHOWERS AND STORMS. THE MOST COVERAGE WILL BE TUE INTO WED AHEAD OF THE FRONT...SOME OF THESE STORMS MAY BECOME STRONG AND THERE COULD BE SOME FLOODING CONCERNS. FINALLY BY THE LAST SOME DAY SOME DRIER AND COOLER AIR WILL BEGIN TO SWEEP IN FROM THE NORTH. && .AVIATION... VFR CONDITIONS PREVAIL ACROSS WEST CENTRAL AND SOUTHWEST FLORIDA TERMINALS. EXPECT THESE CONDITIONS TO PERSIST THROUGH THE EVENING HOURS...WITH THE EXCEPTION OF A SLIGHT CHANCE FOR A SHOWER OR STORM FOR KPGD/KFMY/KRSW. ANY SHOWERS SHOULD DISSIPATE QUICKLY AROUND SUNSET. WINDS SHIFT SOUTH AND THEN SOUTHWEST DURING SATURDAY AND BECOME GUSTY AT TIMES. MOST OF THE SHOWERS AND STORMS ARE EXPECTED TO OCCUR TO THE EAST OF THE FORECAST TERMINALS...SO TAFS SHOW PREVAILING VFR. && .MARINE... WINDS WILL SHIFT TO THE SOUTHEAST TONIGHT AND THEN SOUTHERLY AND SOUTHWESTERLY ON SATURDAY AS HIGH PRESSURE SHIFTS OFF THE SOUTHEAST COAST AND RIDGES BACK TO THE WEST OVER SOUTH FLORIDA AND THE FLORIDA STRAITS. A PERIOD OF CAUTIONARY LEVEL WINDS IS EXPECTED TONIGHT OVER THE NORTHERN WATERS...WITH SOUTHERLY FLOW AT TIMES APPROACHING CAUTIONARY LEVELS OVER THE REMAINDER OF THE FORECAST WATERS DURING THE UPCOMING WEEKEND. && .FIRE WEATHER... A FRONT BISECTS THE STATE THIS AFTERNOON SEPARATING DRIER CONDITIONS NORTH OF THE I-4 CORRIDOR FROM MORE MOIST AND HUMID CONDITIONS TO THE SOUTH. THIS BOUNDARY WILL DISSIPATE AND LIFT NORTH INTO SATURDAY AS SOUTHERLY FLOW DEVELOPS AND ADVECTS HIGHER MOISTURE BACK ACROSS THE REST OF THE STATE. WITH RELATIVE HUMIDITY VALUES ABOVE CRITICAL LEVELS...THE ONLY FIRE WEATHER CONCERNS WILL BE HIGH DISPERSION INDICES ON SATURDAY. FOG POTENTIAL...NO SIGNIFICANT FOG IS EXPECTED THROUGH THE UPCOMING WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... TPA 74 84 76 85 / 0 10 20 30 FMY 74 86 76 90 / 10 10 0 20 GIF 70 89 73 87 / 10 30 10 30 SRQ 73 84 77 85 / 0 10 10 30 BKV 68 88 70 86 / 0 10 30 40 SPG 74 84 77 83 / 0 10 20 30 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...BEACH HAZARDS STATEMENT FROM SATURDAY MORNING THROUGH SUNDAY EVENING FOR COASTAL CHARLOTTE-COASTAL LEE- COASTAL MANATEE-COASTAL SARASOTA-PINELLAS. GULF WATERS...NONE. && $$ SHORT TERM/AVIATION/MARINE/FIRE WEATHER...14/MROCZKA LONG TERM...09/RUDE DECISION SUPPORT...09/RUDE
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1130 AM EDT FRI APR 24 2015 .UPDATE... 15Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS DEEP TROUGHING THROUGH THE DESERT SOUTHWEST INTO NORTHERN MEXICO...FOLLOWED DOWNSTREAM BY AMPLIFIED RIDGING ACROSS THE GULF OF MEXICO AND DEEP SOUTH STATES. MOIST SUBTROPICAL JET IS RIDING NORTHWARD BETWEEN THESE TWO FEATURES OVER THE SOUTHERN PLAINS BEFORE TURNING EASTWARD ACROSS THE SOUTHEAST CONUS. THE FLORIDA PENINSULA RESIDES ON THE EASTERN PERIPHERY OF THE UPPER RIDGE WHERE OUR DEEP LAYER WINDS PER 12Z KTBW SOUNDING PROFILE WERE FROM THE NORTHWEST. SOUNDING DID SHOW A BIT OF A SUBSIDENCE INVERSION ASSOCIATED WITH THE UPPER RIDGE AROUND 700MB...WITH A MOIST PROFILE BELOW THIS LEVEL TO THE SURFACE. AT THE SURFACE... 1020MB CONTINENTAL HIGH PRESSURE RIDGING DOWN INTO THE SOUTHEAST CONUS HAS PUSHED A WEAK FRONTAL BOUNDARY DOWN INTO THE CENTRAL FLORIDA PENINSULA. SEEING A BIG GRADIENT IN SURFACE DEWPOINTS ACROSS THIS BOUNDARY WITH LOWER TO MIDDLE 70S SOUTH OF THE I-4 CORRIDOR...AND THEN QUICKLY DROPPING TO READINGS IN THE 40S UP TOWARD THE I-10 CORRIDOR. THE GENERAL LOCATION OF THE BOUNDARY CAN ALSO BE EASILY SEEN WITH VISIBLE SATELLITE IMAGERY...WHERE A DEFINED CUMULUS DEVELOPMENT CUTOFF IS LOCATED VERY NEAR I-4. SOUTH OF THIS LINE...DIURNAL HEATING IS WORKING WITH THE GREATER BOUNDARY LAYER MOISTURE TO FORM THE SCT-BKN CUMULUS FIELD...WHILE NORTH THE MOISTURE IS SIMPLY NOT IN PLACE TO EFFICIENTLY PRODUCE THE CLOUDS. REGIONAL RADARS SHOW A FEW SHOWERS OVER THE COASTAL WATERS ALONG THIS BOUNDARY...BUT SO FAR NOTHING MORE THAN A FEW SPRINKLES OVER LAND. WILL SEE SOME DEVELOPMENT TO THE SOUTH OF I-4 THIS AFTERNOON...BUT SHOULD NOT BE ANYTHING LIKE THE DEGREE OF CONVECTION EXPERIENCED IN MANY SPOTS DURING THURSDAY. REST OF TODAY... THE FORECAST WILL BE SPLIT NORTH TO SOUTH BY THE BOUNDARY NEAR THE I-4 CORRIDOR. NORTH OF THIS BOUNDARY...THE LACK OF BL MOISTURE MAKES INSTABILITY REALLY LACKING AND DO NOT HAVE THUNDERSTORM MENTION IN THE FORECAST. IN FACT...NONE OF THE HIGH RESOLUTION CONVECTION ALLOWING MODEL MEMBERS ARE PRODUCING ANY RAIN OVER THESE NORTHERN ZONES...SO THE CURRENT FORECAST LOOKS ON TRACK. SOUTH OF THE I-4 CORRIDOR...THE EVENTUAL DEVELOPMENT OF THE SEA- BREEZE SHOULD PROVIDE THE FOCUS FOR A FEW SCT LATE DAY STORMS. HAVE INCREASED POPS TO AROUND 20% AS FAR NORTH AS POLK COUNTY ALONG THE SOUTHERN EDGE OF THE BOUNDARY...AND HAVE CHANCE 30-40% POPS OVER THE SOUTHERN ZONES (MAINLY AWAY FROM THE BEACHES). A SHOWER OR STORMS IS POSSIBLE RIGHT AT THE COAST...HOWEVER THE SEA-BREEZE SHOULD MAKE SOME PROGRESS INLAND...AND MOST OF THE RELIABLE GUIDANCE FAVORS AREAS AWAY FROM THE COAST. TONIGHT... ANY ISOLATED EVENING STORMS WILL DISSIPATE QUICKLY WITH THE LOSS OF DIURNAL HEATING. UPPER RIDGE AXIS WILL BE SHIFTING EASTWARD AND BE CENTERED OVER THE EASTERN GULF OF MEXICO BY EARLY SATURDAY MORNING. SEVERAL UPPER LEVEL SHORTWAVE FEATURES WILL COMBINE WITH EFFICIENT WAA REGIME TO RESULT IN AN ACTIVE CONVECTION NIGHT ACROSS THE LOWER MS VALLEY OVER TO AL/GA. HOWEVER...HIGH PRESSURE SHIFTING OFF THE EASTERN SEABOARD WILL RIDGE BACK TO THE SOUTHWEST OVER OUR HEADS. THIS STACKED RIDGING REGIME SHOULD BE PLENTY TO PROTECT OUR ZONES AND KEEP THIS INCLEMENT WEATHER WELL TO OUR NORTH AND NORTHWEST THROUGH THE OVERNIGHT. SATURDAY... STRONG SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW WILL EJECT OUT OF THE CENTRAL PLAINS INTO THE OHIO/TN VALLEYS...WHILE A SERIES OF WEAKER IMPULSES RIDE EASTWARD ALONG THE NORTH-CENTRAL GULF COAST. THE MOVEMENT OF THESE MASS FIELDS WILL RESULT IN A DE- AMPLIFICATION OF THE UPPER RIDGE OVER OUR REGION THROUGH THE DAY. WARM FRONTAL BOUNDARY WILL BE ALIGNED TO THE NORTH OF THE I-4 CORRIDOR WITH QUITE A BIT OF ONGOING SHOWER AND STORM ACTIVITY FROM THE FLORIDA PANHANDLE TO AL/GA. THE QUESTION FOR OUR FORECAST WILL BE HOW THE WEST COAST SEA-BREEZE BEHAVES THROUGH THE DAY. GENERALLY SPEAKING...THE GOOD SYNOPTIC SETUP FOR LIFT WILL REMAIN TO OUR NORTH TOMORROW...BUT WE WILL HAVE THE SEA-BREEZE TO PROVIDE AT LEAST SOME FOCUS. WIND FIELDS EVOLVE FAVORABLY TOWARD ORGANIZED CONVECTIVE POTENTIAL DURING THE DAY...WITH 0-6KM SHEAR VALUES ELEVATING TO BETWEEN 40-45 KNOTS OVER OUR NORTHERN AREAS FOR THE SECOND HALF OF THE DAY. THESE VALUES...ALTHOUGH NOT EXTREME...ARE CAPABLE OF SUSTAINING ORGANIZED CONVECTION. HERE IS THE PROBLEM FOR OUR AREA...THE 1000-700MB FLOW TOMORROW IS FROM THE W/SW AT 15-25 KNOTS. FIRST OF ALL...THIS WILL KEEP THE WEST COAST SEA- BREEZE FAIRLY WEAK AND DISORGANIZED. SECOND...THE BOUNDARY WILL VERY QUICKLY TRANSLATE INLAND. WITH THIS IN MIND...CURRENT THINKING IS THAT THE BEST CHANCES FOR AFTERNOON THUNDER WOULD BE OVER TOWARD THE FLORIDA EAST COAST...WHERE SEA-BREEZE COLLISION WILL TAKE PLACE. IT IS A TOUGH CALL SINCE ANY CONVECTION THAT DOES DEVELOP WILL BE MOVING QUICKLY AND MAY PRODUCE LOCALLY DAMAGING WINDS...BUT THE OVERALL COVERAGE LOOKS MUCH GREATER EAST AND NORTH OF OUR ZONES. WILL TAKE A CLOSE LOOK AT THE 12Z GUIDANCE PACKAGE AND SEE IF THIS "EAST COAST" PHILOSOPHY STILL SEEMS VALID. && .AVIATION... PERIODS OF MVFR CIGS THIS MORNING AS THE BKN CUMULUS FIELD FILLS IN. THESE CIGS WILL RISE ABOVE VFR LEVELS TOWARD MIDDAY...WITH GENERAL VFR CONDITIONS THEN ANTICIPATED THROUGH THE EVENING HOURS. ONLY EXCEPTIONS WILL BE IN THE VICINITY OF ISOLATED TO SCATTERED PM STORMS ALONG THE SEA-BREEZE. BEST CHANCES AT A LATE DAY STORM WILL BE SOUTH OF THE I-4 CORRIDOR TERMINALS. && .MARINE... NORTHERLY WINDS WILL BE IN PLACE THROUGH TODAY WITH A TURN ONSHORE EXPECTED NEAR THE COAST IN THE AFTERNOON AS THE SEA BREEZE DEVELOPS. FLOW WILL BECOME MORE SOUTHEAST AND THEN SOUTHWEST AND WEST TONIGHT INTO SATURDAY AFTERNOON AS HIGH PRESSURE SINKS TO THE SOUTHEAST. WIND SPEEDS WILL BRIEFLY APPROACH CAUTIONARY LEVELS TONIGHT AND SUNDAY NIGHT FOR THE NORTHERN WATERS...BUT WILL OTHERWISE REMAIN AROUND 15 KNOTS OR LESS THROUGH THE WEEKEND. && .FIRE WEATHER... NO FIRE WEATHER CONCERNS AS RELATIVE HUMIDITY VALUES REMAIN ABOVE CRITICAL LEVELS. && .PRELIMINARY POINT TEMPS/POPS... TPA 87 73 84 75 / 20 10 10 10 FMY 90 73 87 75 / 20 10 10 0 GIF 88 70 87 72 / 20 10 20 10 SRQ 87 72 83 75 / 20 0 0 10 BKV 87 66 86 70 / 10 0 20 10 SPG 86 75 85 76 / 20 0 10 10 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ UPDATE/AVIATION/MARINE/FIRE WEATHER...14/MROCZKA DECISION SUPPORT...RUDE
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
930 AM EDT FRI APR 24 2015 .DISCUSSION... CURRENT-THIS AFTERNOON...FRONTAL TROUGH JUST ENTERING CENTRAL FLORIDA PER THE 0900Z SURFACE ANALYSIS. THE TROUGH WILL WORK ITS WAY DOWN THE FORECAST AREA AND IS FORECAST TO BE CLEAR OF THE SOUTHERN COUNTIES THIS EVENING. ACCOMPANYING WIND SHIFTS FROM THE NORTHWEST TO THE NORTH THEN NORTHEAST THIS AFTERNOON AND EVENING AS THE TROUGH CLEARS AND HIGH PRESSURE BUILDS IN FROM THE NORTH. FIRST COUPLE OF VISIBLE SATELLITE IMAGES SHOWING NOT MUCH IN THE WAY OF MARINE STRATOCUMULUS IN THE NORTHEAST WINDFLOW OFF NORTHEAST FLORIDA...GEORGIA AND THE CAROLINAS. ANY CHANGE(S) TO BE MADE TO THIS AFTERNOON`S FORECAST WOULD BE TO CLOUDS AND THE WIND DIRECTION/SPEED WHICH ARE DEPENDENT ON HOW FAST THE FRONTAL TROUGH MOVES DOWN THE PENINSULA. .AVIATION...MORNING LOW CLOUDS...IFR INITIALLY THEN MVFR WITH HEATING OF THE LOWER LAYERS... FROM ORLANDO INTERNATIONAL (MCO) SOUTH MOVE SOUTH AND CLEAR THE AREA AS THE WINDS SHIFT FROM NORTHWEST TO THE NORTH THEN EVENTUALLY NORTH LATE TODAY/THIS EVENING. .MARINE...THE NOAA BUOYS WERE RECORDING NORTHWEST WINDS 12 TO 14 KNOTS AT 20NM AND 8 KNOTS AT 120NM AND 2 TO 3 FOOT SEAS AT BOTH THE NOAA BUOYS AND THE TWO SCRIPPS BUOYS AT 4 AND 6NM OFF THE BEACH. THE MAYPORT CMAN SITE ALREADY NORTHEAST AND THE SAINT AUGUSTINE SITE NORTH. TRIDENT PIER IN PORT CANAVERAL...BUOY 009 AND SEBASTIAN INLET CMAN SITES STILL NORTHWEST BUT SHOULD SHIFT TO THE NORTH DURING THE AFTERNOON. WINDS SHOULD PICK UP TO NORTHWEST 15 TO 20 KNOTS WELL OFFSHORE THIS AFTERNOON AS THE LEADING EDGE OF THE HIGHER PRESSURE BUILDS IN. THIS WILL PROMPT AN SMALL CRAFT OPERATORS EXERCISE CAUTION FOR WINDS SEBASTIAN INLET NORTH. PREVIOUS DISCUSSION THE TAIL END OF A FRONTAL TROUGH PASSING OFFSHORE THE SE STATES WILL PASS OVER ECFL WITH LITTLE FANFARE DURING THIS MORNING. LOCAL WINDS WILL RESPOND BY VEERING FROM WLY COMPONENT AT DAYBREAK TO NORTH THEN NORTHEAST DURING THE AFTERNOON AS HIGH PRESSURE BUILDS INTO THE AREA BEHIND THE DEPARTING BOUNDARY. AN APPROACHING RIDGE EMBEDDED WITHIN THE PROGRESSIVE WLYS WL BRING WARM CONDS IN THE MID TO UPR 80S ACROSS THE BULK OF THE AREA. RECENT HRRR GUID SUPPORTED BY GFS MOS SHOWS A SMALL RAIN CHC ALONG THE SPACE CST AND TREASURE CST TO LAKE OKEE DURING THE HEAT OF THE AFTERNOON AS THE ONSHORE WINDS COMBINES WITH SFC HEATING AND SOME MODEST MOISTURE TO CREATE ISOLD SHOWERS AND A FAST MOVING STORM OR TWO. PRECIP CHCS WL RANGE FROM UNMENTIONED WEST OF THE I-4 CORRIDOR TO AROUND 20 PERCENT ACROSS THE SOUTH. RAIN CHCS LARGELY TIED TO SFC HEATING AND BOUNDARY INTERACTION WL DIMINISH AFTER NIGHTFALL. LOWS WILL MAKE IT TO THE UPR 60S TO AROUND 70. SAT...SURFACE HIGH CONTINUES TO SLIDE AWAY FROM THE SOUTHEAST COAST INTO THE ATLANTIC AS THE NEXT SYSTEM MOVES ACROSS THE OH/TN VALLEYS AND OFF THE CAROLINA COAST INTO LATE WEEKEND. WHILE MODELS SHOW OVERALL MOISTURE WILL BE SUFFICIENT FOR SCATTERED SHOWERS AND STORMS WITH PWATS 1.6-18"...FORECAST SOUNDINGS SHOW SOME DRIER AIR LINGERING IN THE 850-500MB LEVEL...ESPECIALLY ON SAT...WHICH MAY HELP DELAY CONVECTIVE ONSET UNTIL LATER IN THE AFTERNOON. HOWEVER ANY LINGERING DRY AIR WILL ENHANCE THE WIND THREAT FROM STRONG STORMS ESPECIALLY GIVEN THE MID LAYER WESTERLY FLOW OF 45-55 KNOTS WITH WINDS EVEN IN THE 925-850MB LAYER APPROACHING 30KTS. SPC HAS THE AREA FROM BREVARD AND OSCEOLA COUNTIES NORTHWARDS UNDER A MARGINAL RISK FOR SEVERE WX WITH ISOLATED SEVERE WIND GUSTS THE MAIN HAZARD GIVEN THE BRISK STORM MOTION. A FEW ROTATING STORMS WILL NOT BE OUT OF THE QUESTION ESPECIALLY NEAR THE COAST AS MODELS HINT AT THE EAST COAST SEA BREEZE BOUNDARY TRYING TO FORM RIGHT ALONG THE IMMEDIATE COAST LATE IN THE DAY. ISOLATED SHOWERS POSSIBLE TOWARDS DAYBREAK SUNDAY AS THE FRONT EDGES A LITTLE FURTHER SOUTH AND WEST FLOW INCREASES...BRINGING SOME ACTIVITY FROM OFF THE GULF ACROSS THE PENINSULA. TEMPERATURES CONTINUE ABOVE NORMAL IN THE UPPER 80S AND LOW 90S WITH LOWS IN THE 70S. SUNDAY...WEAK FRONTAL BOUNDARY DROPS INTO N FLORIDA WITH LITTLE SOUTHWARD PROGRESS INTO SUNDAY EVENING. THERE WILL BE A LITTLE BETTER MOISTENING IN THE MID LEVEL GIVEN THE CLOSER PROXIMITY OF THE FRONT WITH BRISK WESTERLY FLOW INCREASING AS SPEEDS AT 925MB COME UP TO 20-30 KNOTS AND 50-55 KNOTS AT 500MB. GIVEN THE STRENGTH OF THE FLOW...NO SEABREEZE DEVELOPMENT IS EXPECTED AND TEMPS WILL BE A FEW DEGREES WARMER...GENERALLY AROUND 90 OR LOW 90S IN MOST LOCATIONS. EXPECT AN EARLY START TO CONVECTION WITH STORMS PROGRESSING QUICKLY FROM WEST TO EAST ACROSS E CENTRAL FL IN THE LATE MORNING AND AFTERNOON HOURS. AS WITH SATURDAY...SPC HAS THE AREA FROM BREVARD AND OSCEOLA COUNTIES NORTHWARDS UNDER A MARGINAL RISK FOR SEVERE WX WITH ISOLATED SEVERE WIND GUSTS CONTINUING TO BE THE MAIN HAZARD. THE PROXIMITY OF THE FRONT AND BRISK FLOW MAY ALLOW AND GULF ACTIVITY OVERNIGHT TO CONTINUE TO MOVE ACROSS THE PENINSULA...MAINLY IN THE FORM OF SHOWERS. MON-THURS...UNSETTLED PATTERN FOR THE FIRST HALF OF THE WEEK AS THE WEEKEND`S FRONTAL BOUNDARY MEANDERS DOWN THE PENINSULA DURING THE DAY ON MONDAY BEFORE STALLING/WASHING OUT ACROSS S FLORIDA LATE IN THE DAY. ROBUST UPPER LEVEL LOW THAT MOVES INTO THE SOUTHERN PLAINS ON MONDAY WILL SLOWLY PHASE WITH A NORTHERN STREAM SHORTWAVE AS IT MOVES INTO THE EASTERN US WEDNESDAY AND THURSDAY. AT THE SURFACE...WEAK BOUNDARY LIFTS BACK NORTH INTO TUESDAY AS 130KT JET SLIDING ACROSS THE NORTHERN GULF OF MEXICO HELPS SPAWN AN ASSOCIATED SURFACE LOW THAT TRACKS ACROSS N FLORIDA/GA LATE WEDNESDAY OR THURSDAY. WHILE THE GFS AND ECMWF SHOW THE SAME BROAD SOLUTION...SOME DIFFERENCES IN TIMING AND EVOLUTION OF THE UPPER LEVEL FEATURES TRANSLATE INTO LARGER DIFFERENCES IN THE STRENGTH OF THE SURFACE LOW. GFS HAS SWUNG BACK TOWARDS A DRIER SOLUTION ON MONDAY...BUT WILL KEEP WITH PREVIOUS RUNS AND KEEP SCT POPS IN THE FORECAST WITH ACTIVITY FOCUSED TOWARDS THE FAR WESTERN INTERIOR...OKEECHOBEE AND TREASURE COAST GIVEN THE LOW LEVEL NE PUSH THAT OCCURS BEHIND THE BOUNDARY. CONSENSUS BETWEEN GFS AND ECMWF STILL KEEP 40-60 PERCENT POPS IN THE FORECAST FOR TUES AND WED AS WEST-SOUTHWEST FLOW TAPS INTO SUBTROPICAL MOISTURE AND PWATS COME UP TO CLOSE TO 2". WIND FIELDS WILL SUPPORT A FEW BREEZY DAYS DURING THE PERIOD WITH THE POSSIBILITY FOR SOME GUSTY STORMS AS WELL. SURFACE LOW PULLS OUT INTO THE ATLANTIC WED NIGHT AND FRONT MOVING THROUGH THE REGION. A FEW SHOWERS MAY LINGER DEPENDING ON THE SPEED OF THE FRONT INTO THURSDAY. && .AVIATION... COTD VFR CONDS THE NEXT 24H OVER MOST SITES WITH EXCEPTION OF SOME PSBL CIGS NR FL 040 AND ISOLD SHRA FM VRB-FPR-SUA-OKE. FM 24/15Z-24/22Z. && .MARINE... TODAY AND TONIGHT...PSG OF THE FRONTAL TROUGH OVER THE WATERS THIS AM WI BRING CHANGING WIND CONDS FROM MORNING INTO THE AFTERNOON. MAIN CONCERN WL BE DEVELOPING NLY TO ONSHORE WIND DURING AFTERNOON WHICH WL INCREASE WAVE HGHTS ALONG WITH BRINGING A WIND CHOP TO LCL WATERS. HEADLINES ARE NOT ANTICIPATED ATTM...HOWEVER SEA STATE WL BEGIN TO RAMP UP ONCE THE NLYS BEHIND THE FRONTAL TROUGH MOVES INTO THE AREA THIS AFTERNOON. SAT-SUN...S/SW WINDS WILL INCREASE TO 15-20 KNOTS SAT AFTERNOON AS GRADIENT INCREASES BETWEEN DEPARTING SURFACE HIGH AND SYSTEM MOVING ACROSS OH/TN VALLEYS. WINDS VEER MORE W/SW INTO SUNDAY AS FRONT DROPS INTO NORTH FLORIDA WITH WINDS CONTINUING 15-20KTS. SEAS WILL INCREASE UP TO 4-5 FT OFFSHORE INTO SUNDAY WITH PERIODS SHORTENING DUE TO THE SHORT FETCH. BOATERS SHOULD BE PREPARED FOR SCATTERED STRONG STORMS APPROACHING FROM THE WEST QUICKLY THIS WEEKEND. MON-WED...FRONT SLIDES THROUGH LATE ON MONDAY WITH WINDS VEERING NORTH THEN NORTHEAST 10-15KTS. BOUNDARY LIFTS BACK INTO REGION INTO TUESDAY WITH WINDS VEERING EAST-SOUTHEAST...THEN INCREASING OUT OF THE SOUTH-SOUTHWEST LATE ON WEDNESDAY AS SURFACE LOW IS FORECASTED TO TRACK ACROSS NORTH FLORIDA. POTENTIAL WILL REMAIN FOR SCATTERED OFFSHORE MOVING STRONG STORMS INTO MID WEEK. && .PRELIMINARY POINT TEMPS/POPS... DAB 80 68 85 72 / 10 10 30 20 MCO 86 70 87 71 / 10 10 30 10 MLB 82 71 87 72 / 20 10 30 20 VRB 82 69 87 72 / 20 10 20 10 LEE 86 70 84 73 / 10 10 30 20 SFB 84 69 86 74 / 10 10 30 20 ORL 85 70 86 72 / 10 10 30 20 FPR 84 69 88 71 / 20 10 20 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ LONG TERM/IMPACT WX...JOHNSON SHORT TERM/AVIATION...WIMMER
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
426 AM EDT FRI APR 24 2015 .SHORT TERM...COLD FRONT LOCATED ACROSS THE CENTRAL PORTIONS OF THE AREA EARLY THIS MORNING...ORIENTED SW TO NE FROM THE NE GULF TO THE ATLC COASTAL WATERS WILL CONTINUE TO DROP SWD AND MOVE INTO N CENTRAL FL BY MID MORNING. SOME PATCHY FOG/LOW STRATUS WILL BE POSSIBLE OVER THE COURSE OF THE NEXT FEW HOURS OVER THE I-75 CORRIDOR BUT SCT-BROKEN MID DECK CLOUDS MAY KEEP VSBY FROM GOING MUCH BELOW 1-2 MILES. A SURGE OF NELY WINDS WILL OCCUR BEHIND THIS BOUNDARY WITH OVERALL DRIER AIRMASS ADVECTING IN...ESPECIALLY ACROSS OUR NRN AND NW ZONES. NIL POPS TODAY...WITH SKIES PARTLY CLOUDY. TEMPS COOLER THAN YESTERDAY WITH HIGHS IN THE UPPER 70S N ZONES TO MID 80S SW ZONES. BREEZY NELY WINDS AT THE COAST/BEACHES AROUND 15- 20G30MPH AT TIMES. THE BREEZY ONSHORE WINDS SHOULD DIMINISH BY 5-6 PM. TONIGHT...COLD FRONT THAT DROPS INTO CENTRAL FL TODAY STALLS TO OUR S THEN BEGINS TO MAKE A NWD PUSH BY THE EARLY MORNING HOURS WITH SKY COVER INCREASING WITH ISENTROPIC LIFT DEVELOPING RAPIDLY AFTER 06Z. MINS FCST IN THE UPPER 50S TO MID 60S. HAVE TRIMMED BACK POPS TO LESS THAN 15 PERCENT BASED ON LATEST GUIDANCE...BUT CAN`T RULE OUT A FEW SPRINKLES ACROSS WRN ZONES AS ISENTROPIC ASCENT INCREASES. .SHORT TERM (SATURDAY THROUGH SUNDAY NIGHT)... TROUGHING ALOFT WILL MIGRATE EASTWARD ACROSS THE PLAINS STATES AND THE UPPER MIDWEST ON SATURDAY...REACHING THE OHIO VALLEY SATURDAY NIGHT. MEANWHILE...RIDGING ALOFT WILL REMAIN CENTERED OVER THE NORTHWESTERN CARIBBEAN...RESULTING IN STRENGTHENING WESTERLY FLOW OVER OUR REGION. A WARM FRONT WILL LIFT NORTHWARD INTO SOUTHEAST GA ON SATURDAY MORNING...WITH STRENGTHENING ISENTROPIC LIFT NORTH OF THIS BOUNDARY POSSIBLY DEVELOPING A FEW SHOWERS ON SATURDAY MORNING NEAR THE ALTAMAHA RIVER. OUR AREA WILL THEN BE LOCATED IN THE WARM SECTOR WELL IN ADVANCE OF A COLD FRONT THAT WILL BE SWEEPING THROUGH THE LOWER MISSISSIPPI VALLEY. SHORTWAVE ENERGY IS PROGGED TO MOVE INTO SOUTHEAST GA FROM THE WEST DURING THE AFTERNOON HOURS ON SATURDAY...WHICH SHOULD IGNITE AT LEAST SCATTERED AFTERNOON CONVECTION OVER INLAND SOUTHEAST GA AND THE SUWANNEE VALLEY...WITH THE GULF COAST SEA BREEZE BEING THE LIKELY TRIGGER MECHANISM IN FL. CONVECTIVE ACTIVITY WILL BECOME WIDESPREAD OVER SOUTHEAST GA BY LATE AFTERNOON...WITH LIKELY POPS FOR COASTAL NORTHEAST FL AS ACTIVITY ENCOUNTERS A PINNED ATLANTIC SEA BREEZE DURING THE LATE AFTERNOON. LESS ACTIVITY IS EXPECTED FOR LOCATIONS SOUTH OF GAINESVILLE/ST. AUGUSTINE AS MID-LEVEL DRY AIR ADVECTS OVERHEAD FROM THE NORTHEASTERN GULF. MODEL SOUNDINGS DEPICT A STRENGTHENING LOW-LEVEL VEERING PROFILE AND MARGINAL INSTABILITY...WITH CAPES OF 1000-1500 J/KG AND 500 MB TEMPS AROUND - 9 CELSIUS. GIVEN THESE VARIABLES AND STRENGTHENING SW/W WINDS JUST OFF THE SURFACE...THE STORM PREDICTION CENTER HAS PLACED AREAS ALONG AND NORTH OF INTERSTATE 10 WITHIN A SLIGHT RISK FOR SEVERE THUNDERSTORM DEVELOPMENT ON SATURDAY AFTERNOON...WITH A MARGINAL RISK FOR THE REST OF NORTHEAST AND NORTH CENTRAL FL. HIGHS WILL CLIMB INTO THE 80S. STRONG DOWNBURST WINDS AND HAIL APPEAR TO BE THE PRIMARY HAZARDS THROUGH SUNSET BEFORE ACTIVITY MOVES OFFSHORE. STRONG W/SW FLOW WILL PERSIST ON SATURDAY NIGHT AND SUNDAY LOCALLY. THIS MAY DEVELOP AN EARLY MORNING CONVECTIVE COMPLEX OVER THE NORTHEAST GULF OF MEXICO THAT MAY MOVE ONSHORE INTO THE SUWANNEE VALLEY ON SUNDAY MORNING. ABOVE NORMAL LOWS ARE EXPECTED...WITH UPPER 60S TO LOWER 70S. EXPECT ANOTHER SEASONABLY WARM DAY REGION- WIDE...WITH SCATTERED AFTERNOON CONVECTION OVER NORTHEAST AND NORTH CENTRAL FL DEVELOPING ALONG THE GULF COAST SEA BREEZE. DRY AIR ALOFT WILL SINK SOUTHWARD INTO SOUTHEAST GA AS TROUGHING ALOFT DIGS SOUTHWARD OVER THE MID-ATLANTIC STATES...LIMITING CONVECTIVE COVERAGE FOR LOCATIONS NORTH OF WAYCROSS TO BRUNSWICK. A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE OVER FL...WHERE MODEL SOUNDINGS DEPICT A VERY UNSTABLE ATMOSPHERE. HOWEVER...OVERALL FORCING IS QUESTIONABLE...AND THUS DECIDED TO USE SCATTERED COVERAGE. THE STORM PREDICTION CENTER HAS PLACED OUR REGION WITHIN A MARGINAL RISK FOR SEVERE THUNDERSTORM DEVELOPMENT ON SUNDAY. STRONG OFFSHORE FLOW WILL BOOST HIGHS TO THE 85-90 RANGE REGION- WIDE. A COLD FRONT WILL THEN SINK SOUTHWARD THROUGH OUR REGION ON SUNDAY NIGHT...WITH CONVECTION CONCLUDING DURING THE EARLY EVENING HOURS. LOWS WILL RANGE FROM THE MID 60S NORTH TO THE LOWER 70S OVER NORTH CENTRAL FL. .LONG TERM (MONDAY THROUGH FRIDAY)... A POTENT SHORTWAVE TROUGH WILL EMERGE FROM THE DESERT SOUTHWEST EARLY MONDAY. THIS FEATURE WILL MOVE EASTWARD ACROSS THE DEEP SOUTH THROUGH MIDWEEK. THE COLD FRONT THAT MOVES THROUGH OUR REGION ON SUNDAY NIGHT WILL STALL OVER CENTRAL FL MONDAY...AND THEN WILL RETREAT NORTHWARD AS A WARM FRONT ON TUESDAY. EXPECT WIDELY SCATTERED AFTERNOON CONVECTION OVER MAINLY INLAND LOCATIONS OF NORTHEAST AND NORTH CENTRAL FL MONDAY...WITH A DRY AIR MASS IN SOUTHEAST GA EXPECTED TO KEEP THINGS DRY. HIGHS WILL RANGE FROM THE MID 70S AT THE COAST DUE TO DEVELOPING ONSHORE FLOW TO THE LOWER 80S IN NORTH CENTRAL FL. SCATTERED CONVECTION WILL BE POSSIBLE OVER FL ON MONDAY NIGHT AS THE FRONT BEGINS TO RETREAT NORTHWARD...WITH DRY CONDITIONS CONTINUING IN SOUTHEAST GA. LOWS WILL RANGE FROM NEAR 60 FOR INTERIOR SOUTHEAST GA TO THE MID/UPPER 60S IN FL. LIKELY POPS ARE EXPECTED TUES AND TUES NIGHT AS THE WARM FRONT AND SHORTWAVE ENERGY MIGRATE THROUGH OUR AREA. DEPENDING ON THE STRENGTH OF SHORTWAVE ENERGY...STRONG TO SEVERE CONVECTION IS POSSIBLE ALONG THE WARM FRONT TUES AND ALONG A COLD FRONT/STRENGTHENING SURFACE LOW WED. HIGHS BOTH DAYS WILL RANGE FROM 75-80...WITH LOWS IN THE 60S. A SLIGHTLY COOLER AND MUCH DRIER AIR MASS WILL PLUNGE INTO OUR REGION LATE NEXT WEEK...WITH HIGHS GENERALLY IN THE 70S AND LOWS FALLING TO THE 55-60 RANGE. && .AVIATION...PREVAILING VFR WITH POSSIBILITY OF MVFR VSBY/LOW STRATUS FOR A BRIEF TIME AT GNV EARLY THIS MORNING. OTHERWISE...WINDS WILL SHIFT AROUND TO N EARLY THEN NE BY MID MORNING. STRONGER NE WINDS FOR SSI...CRG...SGJ...JAX AND VQQ TERMINALS UP AROUND 12-15G20KT THEN WEAKENING BY THIS EVENING AND TURNING E TO SE OVERNIGHT AT 10 KT OR LESS. && .MARINE...W TO NW WINDS 10 KT OR LESS EARLY THIS MORNING WILL BECOMING STRONGER OUT OF THE TO N TO NE BEHIND EARLY COLD FRONTAL PASSAGE. HIGH-RES MODEL GUIDANCE AND BUOYS SHOW WE WILL LIKELY REACH SCA CONDITIONS FOR ABOUT A 4-8 HOUR PERIOD TODAY SO HOISTED SCA FOR THE NRN WATERS TIL 4 PM TODAY THOUGH COULD BE SLIGHTLY EARLIER BASED ON LATEST RAP MODEL. SEAS FCST TO BUILD TO ABOUT 4-6 FT BY MID DAY. FOR SRN WATERS S OF THE ST AUGUSTINE SCEC HEADLINE WILL SUFFICE. WINDS WILL INCREASE ON SATURDAY AND SATURDAY NIGHT VEERING FROM SOUTHERLY TO WESTERLY AS NEXT STORM SYSTEM PASSES TO OUR N. NEXT COLD FRONT MOVES INTO THE AREA WATERS EARLY MONDAY MORNING...STALLING MONDAY NIGHT OVER CENTRAL FL. A SFC LOW PRESSURE APPROACHES FROM THE W ON TUESDAY. RIP CURRENTS: MODERATE RISK AS SURF BUILDS TODAY. LOW TO MODERATE RISK FOR SATURDAY. && .PRELIMINARY POINT TEMPS/POPS... AMG 78 59 82 68 / 10 10 70 40 SSI 71 63 79 70 / 0 10 60 40 JAX 76 63 85 70 / 0 10 60 40 SGJ 74 67 85 71 / 10 10 50 20 GNV 82 63 87 71 / 10 10 40 20 OCF 86 65 86 71 / 10 10 30 20 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 4 PM EDT THIS AFTERNOON FOR COASTAL WATERS FROM ALTAMAHA SOUND TO FERNANDINA BEACH FL OUT 20 NM-COASTAL WATERS FROM FERNANDINA BEACH TO ST. AUGUSTINE FL OUT 20 NM-WATERS FROM ALTAMAHA SOUND GA TO FERNANDINA BEACH FL FROM 20 TO 60 NM- WATERS FROM FERNANDINA BEACH TO ST. AUGUSTINE FL FROM 20 TO 60 NM. && $$ SHASHY/NELSON
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
339 AM EDT FRI APR 24 2015 .DISCUSSION... THE TAIL END OF A FRONTAL TROUGH PASSING OFFSHORE THE SE STATES WILL PASS OVER ECFL WITH LITTLE FANFARE DURING THIS MORNING. LOCAL WINDS WILL RESPOND BY VEERING FROM WLY COMPONENT AT DAYBREAK TO NORTH THEN NORTHEAST DURING THE AFTERNOON AS HIGH PRESSURE BUILDS INTO THE AREA BEHIND THE DEPARTING BOUNDARY. AN APPROACHING RIDGE EMBEDDED WITHIN THE PROGRESSIVE WLYS WL BRING WARM CONDS IN THE MID TO UPR 80S ACROSS THE BULK OF THE AREA. RECENT HRRR GUID SUPPORTED BY GFS MOS SHOWS A SMALL RAIN CHC ALONG THE SPACE CST AND TREASURE CST TO LAKE OKEE DURING THE HEAT OF THE AFTERNOON AS THE ONSHORE WINDS COMBINES WITH SFC HEATING AND SOME MODEST MOISTURE TO CREATE ISOLD SHOWERS AND A FAST MOVING STORM OR TWO. PRECIP CHCS WL RANGE FROM UNMENTIONED WEST OF THE I-4 CORRIDOR TO AROUND 20 PERCENT ACROSS THE SOUTH. RAIN CHCS LARGELY TIED TO SFC HEATING AND BOUNDARY INTERACTION WL DIMINISH AFTER NIGHTFALL. LOWS WILL MAKE IT TO THE UPR 60S TO AROUND 70. SAT...SURFACE HIGH CONTINUES TO SLIDE AWAY FROM THE SOUTHEAST COAST INTO THE ATLANTIC AS THE NEXT SYSTEM MOVES ACROSS THE OH/TN VALLEYS AND OFF THE CAROLINA COAST INTO LATE WEEKEND. WHILE MODELS SHOW OVERALL MOISTURE WILL BE SUFFICIENT FOR SCATTERED SHOWERS AND STORMS WITH PWATS 1.6-18"...FORECAST SOUNDINGS SHOW SOME DRIER AIR LINGERING IN THE 850-500MB LEVEL...ESPECIALLY ON SAT...WHICH MAY HELP DELAY CONVECTIVE ONSET UNTIL LATER IN THE AFTERNOON. HOWEVER ANY LINGERING DRY AIR WILL ENHANCE THE WIND THREAT FROM STRONG STORMS ESPECIALLY GIVEN THE MID LAYER WESTERLY FLOW OF 45-55 KNOTS WITH WINDS EVEN IN THE 925-850MB LAYER APPROACHING 30KTS. SPC HAS THE AREA FROM BREVARD AND OSCEOLA COUNTIES NORTHWARDS UNDER A MARGINAL RISK FOR SEVERE WX WITH ISOLATED SEVERE WIND GUSTS THE MAIN HAZARD GIVEN THE BRISK STORM MOTION. A FEW ROTATING STORMS WILL NOT BE OUT OF THE QUESTION ESPECIALLY NEAR THE COAST AS MODELS HINT AT THE EAST COAST SEA BREEZE BOUNDARY TRYING TO FORM RIGHT ALONG THE IMMEDIATE COAST LATE IN THE DAY. ISOLATED SHOWERS POSSIBLE TOWARDS DAYBREAK SUNDAY AS THE FRONT EDGES A LITTLE FURTHER SOUTH AND WEST FLOW INCREASES...BRINGING SOME ACTIVITY FROM OFF THE GULF ACROSS THE PENINSULA. TEMPERATURES CONTINUE ABOVE NORMAL IN THE UPPER 80S AND LOW 90S WITH LOWS IN THE 70S. SUNDAY...WEAK FRONTAL BOUNDARY DROPS INTO N FLORIDA WITH LITTLE SOUTHWARD PROGRESS INTO SUNDAY EVENING. THERE WILL BE A LITTLE BETTER MOISTENING IN THE MID LEVEL GIVEN THE CLOSER PROXIMITY OF THE FRONT WITH BRISK WESTERLY FLOW INCREASING AS SPEEDS AT 925MB COME UP TO 20-30 KNOTS AND 50-55 KNOTS AT 500MB. GIVEN THE STRENGTH OF THE FLOW...NO SEABREEZE DEVELOPMENT IS EXPECTED AND TEMPS WILL BE A FEW DEGREES WARMER...GENERALLY AROUND 90 OR LOW 90S IN MOST LOCATIONS. EXPECT AN EARLY START TO CONVECTION WITH STORMS PROGRESSING QUICKLY FROM WEST TO EAST ACROSS E CENTRAL FL IN THE LATE MORNING AND AFTERNOON HOURS. AS WITH SATURDAY...SPC HAS THE AREA FROM BREVARD AND OSCEOLA COUNTIES NORTHWARDS UNDER A MARGINAL RISK FOR SEVERE WX WITH ISOLATED SEVERE WIND GUSTS CONTINUING TO BE THE MAIN HAZARD. THE PROXIMITY OF THE FRONT AND BRISK FLOW MAY ALLOW AND GULF ACTIVITY OVERNIGHT TO CONTINUE TO MOVE ACROSS THE PENINSULA...MAINLY IN THE FORM OF SHOWERS. MON-THURS...UNSETTLED PATTERN FOR THE FIRST HALF OF THE WEEK AS THE WEEKEND`S FRONTAL BOUNDARY MEANDERS DOWN THE PENINSULA DURING THE DAY ON MONDAY BEFORE STALLING/WASHING OUT ACROSS S FLORIDA LATE IN THE DAY. ROBUST UPPER LEVEL LOW THAT MOVES INTO THE SOUTHERN PLAINS ON MONDAY WILL SLOWLY PHASE WITH A NORTHERN STREAM SHORTWAVE AS IT MOVES INTO THE EASTERN US WEDNESDAY AND THURSDAY. AT THE SURFACE...WEAK BOUNDARY LIFTS BACK NORTH INTO TUESDAY AS 130KT JET SLIDING ACROSS THE NORTHERN GULF OF MEXICO HELPS SPAWN AN ASSOCIATED SURFACE LOW THAT TRACKS ACROSS N FLORIDA/GA LATE WEDNESDAY OR THURSDAY. WHILE THE GFS AND ECMWF SHOW THE SAME BROAD SOLUTION...SOME DIFFERENCES IN TIMING AND EVOLUTION OF THE UPPER LEVEL FEATURES TRANSLATE INTO LARGER DIFFERENCES IN THE STRENGTH OF THE SURFACE LOW. GFS HAS SWUNG BACK TOWARDS A DRIER SOLUTION ON MONDAY...BUT WILL KEEP WITH PREVIOUS RUNS AND KEEP SCT POPS IN THE FORECAST WITH ACTIVITY FOCUSED TOWARDS THE FAR WESTERN INTERIOR...OKEECHOBEE AND TREASURE COAST GIVEN THE LOW LEVEL NE PUSH THAT OCCURS BEHIND THE BOUNDARY. CONSENSUS BETWEEN GFS AND ECMWF STILL KEEP 40-60 PERCENT POPS IN THE FORECAST FOR TUES AND WED AS WEST-SOUTHWEST FLOW TAPS INTO SUBTROPICAL MOISTURE AND PWATS COME UP TO CLOSE TO 2". WIND FIELDS WILL SUPPORT A FEW BREEZY DAYS DURING THE PERIOD WITH THE POSSIBILITY FOR SOME GUSTY STORMS AS WELL. SURFACE LOW PULLS OUT INTO THE ATLANTIC WED NIGHT AND FRONT MOVING THROUGH THE REGION. A FEW SHOWERS MAY LINGER DEPENDING ON THE SPEED OF THE FRONT INTO THURSDAY. && .AVIATION... COTD VFR CONDS THE NEXT 24H OVER MOST SITES WITH EXCEPTION OF SOME PSBL CIGS NR FL 040 AND ISOLD SHRA FM VRB-FPR-SUA-OKE. FM 24/15Z-24/22Z. && .MARINE... TODAY AND TONIGHT...PSG OF THE FRONTAL TROUGH OVER THE WATERS THIS AM WI BRING CHANGING WIND CONDS FROM MORNING INTO THE AFTERNOON. MAIN CONCERN WL BE DEVELOPING NLY TO ONSHORE WIND DURING AFTERNOON WHICH WL INCREASE WAVE HGHTS ALONG WITH BRINGING A WIND CHOP TO LCL WATERS. HEADLINES ARE NOT ANTICIPATED ATTM...HOWEVER SEA STATE WL BEGIN TO RAMP UP ONCE THE NLYS BEHIND THE FRONTAL TROUGH MOVES INTO THE AREA THIS AFTERNOON. SAT-SUN...S/SW WINDS WILL INCREASE TO 15-20 KNOTS SAT AFTERNOON AS GRADIENT INCREASES BETWEEN DEPARTING SURFACE HIGH AND SYSTEM MOVING ACROSS OH/TN VALLEYS. WINDS VEER MORE W/SW INTO SUNDAY AS FRONT DROPS INTO NORTH FLORIDA WITH WINDS CONTINUING 15-20KTS. SEAS WILL INCREASE UP TO 4-5 FT OFFSHORE INTO SUNDAY WITH PERIODS SHORTENING DUE TO THE SHORT FETCH. BOATERS SHOULD BE PREPARED FOR SCATTERED STRONG STORMS APPROACHING FROM THE WEST QUICKLY THIS WEEKEND. MON-WED...FRONT SLIDES THROUGH LATE ON MONDAY WITH WINDS VEERING NORTH THEN NORTHEAST 10-15KTS. BOUNDARY LIFTS BACK INTO REGION INTO TUESDAY WITH WINDS VEERING EAST-SOUTHEAST...THEN INCREASING OUT OF THE SOUTH-SOUTHWEST LATE ON WEDNESDAY AS SURFACE LOW IS FORECASTED TO TRACK ACROSS NORTH FLORIDA. POTENTIAL WILL REMAIN FOR SCATTERED OFFSHORE MOVING STRONG STORMS INTO MID WEEK. && .PRELIMINARY POINT TEMPS/POPS... DAB 80 68 85 72 / 10 10 30 20 MCO 86 70 87 71 / 10 10 30 10 MLB 82 71 87 72 / 20 10 30 20 VRB 82 69 87 72 / 20 10 20 10 LEE 86 70 84 73 / 10 10 30 20 SFB 84 69 86 74 / 10 10 30 20 ORL 85 70 86 72 / 10 10 30 20 FPR 84 69 88 71 / 20 10 20 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM...PENDERGRAST LONG TERM....MOSES
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1041 PM EDT SAT APR 25 2015 .SYNOPSIS... DRIER WEATHER RETURNS FOR SUNDAY AS A COLD FRONT MOVES SOUTH ACROSS THE REGION. THE NEXT CHANCE FOR SIGNIFICANT RAIN MOVES IN FOR THE MIDDLE OF NEXT WEEK AS MOISTURE INCREASES AHEAD OF A LOW PRESSURE SYSTEM COMING OUT OF THE GULF OF MEXICO. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... A FRONTAL BOUNDARY IS POSITIONED JUST SOUTH OF THE NC/SC BORDER TONIGHT. OBSERVATIONS SHOW NORTHEASTERLY WINDS NORTH OF THE BOUNDARY AND SOUTHWESTERLY WINDS FOR A MAJORITY OF THE FORECAST AREA WHICH IS SOUTH OF THE BOUNDARY. EXPECT ISOLATED SHOWERS AND STORMS TO CONTINUE BEHIND THE QLCS DEPARTING OFF THE COAST. THE HIGHEST MOISTURE IS CURRENTLY ALONG THE SOUTHERN AND EASTERN COUNTIES. MESOANALYSIS ALSO SHOWS WEAK TO MODERATE INSTABILITY REMAINS ACROSS THE SOUTHERN HALF OF THE FORECAST AREA WITH LIFTED INDICES AS LOW AS -4/-5 IN THE SOUTHERNMOST PART OF THE FA. EXPECT THIS AREA TO SEE A MAJORITY OF THE SHOWER ACTIVITY OVER THE NEXT HOUR OR TWO. THE HRRR SEEMS TO BE HANDLING THE ACTIVITY FAIRLY WELL AND SHOWS MOST OF THE ACTIVITY DEPARTING THE FORECAST AREA BY 06Z SO HAVE TRENDED POPS DOWN OVERNIGHT. OBSERVATIONS SHOW LOW VISIBILITIES IN LANCASTER AND CHESTERFIELD COUNTIES CLOSE TO THE FRONTAL BOUNDARY ALTHOUGH LOW LEVEL JET SHOULD LIMIT FOG POTENTIAL SOME OVERNIGHT. OVERNIGHT LOWS REMAIN MILD...ONLY FALLING INTO THE LOWER TO MIDDLE 60S. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... SOME LINGERING SHOWERS/STORMS POSSIBLE INTO SUNDAY WITH THE NORTHERN MIDLANDS LIKELY TO BE MORE FAVORED SUNDAY AS THE SURFACE LOW SINKS SOUTHEASTWARD ACROSS VA/NC AND OFFSHORE BY SUNDAY EVENING. MODERATE TO STRONG INSTABILITY AND COLD 500 MB TEMPS NOTED ON SUNDAY BUT MOISTURE MAY BE LACKING TO SUPPORT MUCH CONVECTION SO WILL CONTINUE WITH LOW CHANCE POPS ACROSS THE NORTHERN MIDLANDS. SUNDAY LOOKS TO BE A WARM DAY WITH SOME SUNSHINE AND DOWNSLOPING NORTHWESTERLY FLOW WITH HIGHS BACK INTO THE 80S. THE EXCEPTION WILL BE THE EXTREME NORTHERN MIDLANDS WHERE COOLER BEHIND THE AREA OF LOW PRESSURE SHOULD HOLD TEMPERATURES IN THE 70S. && .LONG TERM /MONDAY THROUGH SATURDAY/... MEDIUM-RANGE MODELS IN FAIRLY GOOD AGREEMENT WITH THE OVERALL PATTERN NEXT WEEK. ON MON/TUE THE FORECAST AREA WILL BE BETWEEN THE DEPARTING SYSTEM OFF THE EAST COAST AND YET ANOTHER SLOW MOVING CLOSED UPPER LOW EJECTING EASTWARD OUT OF THE SOUTHWESTERN STATES. EXPECT DRY WEATHER AND BELOW NORMAL TEMPERATURES WITH A PERSISTENT NORTHERLY FLOW AND SURFACE HIGH PRESSURE RIDGING INTO THE AREA FROM THE NORTH. THE SOUTHERN STREAM CLOSED LOW WILL BEGIN TO OPEN AND DRIFT EASTWARD EVENTUALLY PHASING WITH NORTHERN STREAM ENERGY BRINGING UNSETTLED WEATHER TO OUR AREA TUESDAY INTO THURSDAY. HOWEVER...THERE ARE SOME DIFFERENCES BETWEEN THE LATEST GFS RUN AND THE PREVIOUS ECMWF FOR THE LATTER PART OF THE PERIOD. THE PREVIOUS ECMWF SHOWS SOME LINGERING PRECIPITATION OVER THE AREA FRIDAY WITH HIGH PRESSURE OVER THE AREA SATURDAY. THE LATEST GFS SHOWS DRY HIGH PRESSURE BUILDING IN FROM THE WEST FRIDAY INTO SATURDAY...BUT ALSO SHOWS ANOTHER CUT-OFF UPPER LOW FORMING OVER THE EASTERN GULF COAST. THIS FEATURE COULD SPREAD PRECIPITATION BACK INTO SC BY LATE SATURDAY. DUE TO UNCERTAINTY...WILL KEEP FRIDAY AND SATURDAY DRY AT THIS TIME. TEMPERATURES GENERALLY AT OR JUST BELOW NORMAL THROUGH THE EXTENDED PERIOD. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... THE MAIN LINE OF SHOWERS AND STORMS HAS SHIFTED OFF THE COAST TONIGHT WITH ISOLATED ACTIVITY REMAINING ACROSS THE SOUTHEASTERN PORTION OF THE FORECAST AREA. NO RESTRICTIONS AT THE TAF SITES CURRENTLY BUT CANNOT RULE OUT A SHOWER OR STORM AFFECTING AGS/DNL SO HAVE HAVE A TEMPO GROUP THROUGH 03Z. MODELS INDICATE POTENTIAL FOR RESTRICTIONS RETURNING AFTER 06Z ALTHOUGH BELIEVE LOW LEVEL JET WILL LIMIT FOG POTENTIAL. HAVE ADDED MVFR RESTRICTIONS AT AGS/DNL TOWARDS DAYBREAK ALTHOUGH CONFIDENCE IS LOW AT THIS TIME. THE LOW- LEVEL JET SUPPORTS KEEPING LLWS IN THE TERMINAL FORECASTS OVERNIGHT. USED THE NAM FOR THE MAGNITUDE OF THE SHEAR. THE MODELS SHOW THE BOUNDARY SINKING SOUTHWARD SUNDAY BUT WITH SHALLOW MOISTURE. THE THUNDERSTORM CHANCE STILL APPEARED TOO LOW TO INCLUDE IN THE TERMINAL FORECAST. BASED ON THE GFS LAMP AND THE NAM BUFKIT MOMENTUM TRANSFER TOOL WE INCLUDED WIND GUSTS NEAR 24 KNOTS. EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED MONDAY AND TUESDAY. AN APPROACHING WARM FRONT MAY RESULT IN WIDESPREAD RESTRICTIONS WEDNESDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS BOISE ID
837 PM MDT SAT APR 25 2015 .DISCUSSION...EXPECT GUSTY WINDS AND DECREASING SHOWERS. NO UPDATES NEEDED. RADAR AND SATELLITE SHOWED AN AREA OF SHOWERS FROM PARTS OF MALHEUR...CANYON AND OWYHEE COUNTIES TO THE NW AND SE. THE HRRR RADAR DEPICTION HAD THIS...AS WELL AS SHOWERS THROUGH THE WEST CENTRAL ID MTNS...WHICH SHOULD DECAY BY MIDNIGHT. LIGHTNING WAS DETECTED OVER CENTRAL MALHEUR COUNTY AND AS OF 823PM THE STRONGEST CELL CAPABLE OF LIGHTNING APPEARED EAST OF DUCK VALLEY MOVING INTO NV. CLOSER TO THE NRN LOW CENTER THERE WAS MORE CONVECTIVE ACTION /NEAR THE BLUE MTNS/ WHILE COLDEST CLOUD TOPS WERE MOSTLY EAST OF OUR AREA. COULD SEE A LINGERING SNOW SHOWER ACROSS E VALLEY COUNTY OR S TWIN FALLS COUNTY AFTER MIDNIGHT BUT CHANCES ARE SLIM...AS MENTIONED EARLIER. WIND GUSTS NEAR SHOWERS ACROSS THE TREASURE VALLEY COULD APPROACH 45 MPH THROUGH 930 OR 10 PM...WITH WINDS REBUILDING SUNDAY TO 25-40 MPH ACROSS WINDIER AREAS /KMUO/ BEFORE DECREASING SUNDAY EVENING. FORECAST ON TRACK FOR NO UPDATES. && .AVIATION...VFR WITH AREAS OF LOW VFR IN ISOLATED SHOWERS. SHOWERS WILL DIE OUT OVER THE COURSE OF THE EVENING...LINGERING A LITTLE LONGER OVER THE WEST CENTRAL IDAHO MOUNTAINS. SURFACE WINDS...NORTHWESTERLY...GENERALLY 10-20 KTS WITH STRONGER GUSTS IN SHOWERS...BECOMING STRONGER UP TO 35 KTS ALONG THE SNAKE RIVER PLAIN IN THE MORNING. WINDS ALOFT NEAR 10K FT MSL...NW 15-15 KTS...BECOMING NNW 20-30 KTS BY 26/12Z...AND NNW 10-20 KTS BY 27/00Z. && .PREV DISCUSSION... SHORT TERM...TONIGHT THROUGH MONDAY...THE SOUTHERN PORTION OF A SPLITTING UPPER TROUGH WILL BE THE FOCUS FOR DEEPER CONVECTION ACROSS NEVADA WHICH EXTENDS TO JUST NORTH OF THE IDAHO/NEVADA BORDER. MODELS CONTINUE TO SHOW THAT THE NORTHERN PORTION OF THE SPLIT /A CLOSED UPPER LOW OVER WASHINGTON/ WILL BE THE MAIN FOCUS FOR SHOWERS THROUGH THIS EVENING AS IT MOVES TO THE S-SE AND WEAKENS OVERNIGHT. THE SHOWERS WILL DISSIPATE FOR MOST AREAS AFTER SUNSET BUT COULD LINGER ACROSS EASTERN PORTIONS OF THE FORECAST AREA /GENERALLY EAST OF A MCCALL-TWIN FALLS LINE/ THROUGH EARLY SUNDAY MORNING. A DEEPENING SURFACE LOW OVER EASTERN UTAH/WESTERN COLORADO WILL ENHANCE THE W-NW WINDS TONIGHT THROUGH SUNDAY...ESPECIALLY IN THE FAVORED WINDY CORRIDOR FROM MOUNTAIN HOME TO TWIN FALLS. WINDS ARE NOT EXPECTED TO EXCEED WIND ADVISORY CRITERIA...BUT THEY WILL BE CLOSE TO SUSTAINED 30 MPH AND/OR GUSTS TO 45 MPH FROM LATE SUNDAY MORNING THROUGH SUNDAY AFTERNOON. TEMPERATURES WILL BE SLIGHTLY HIGHER ON SUNDAY AS AN UPPER RIDGE STARTS TO BUILD INTO THE PACNW. THE RIDGE WILL CONTINUE TO AMPLIFY OVER THE REGION SUNDAY NIGHT THROUGH MONDAY...RESULTING IN LIGHT WINDS AND MOSTLY CLEAR SKIES. TEMPERATURES WILL REBOUND TO ABOVE NORMAL ON MONDAY. LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A RIDGE OF HIGH PRESSURE WILL BRING A WARMING TREND STARTING MONDAY THROUGH WEDNESDAY. TEMPERATURES WILL NEAR 80F IN THE LOWER VALLEYS ON TUESDAY AS THE RIDGE AXIS MOVES OVERHEAD...OR AROUND 15 DEGREES ABOVE NORMAL. BY WEDNESDAY THE RIDGE AXIS BEGINS TO SHIFT EAST AND COOLER AIR WILL WORK ITS WAY INTO THE PACIFIC NORTHWEST AHEAD OF A COOL UPPER LEVEL TROUGH IN THE GULF OF ALASKA. A WEAK SHORTWAVE EXPECTED TO MOVE ACROSS THE AREA ON THURSDAY. MODELS ARE MUCH STRONGER WITH THE COLD FRONT ON THURSDAY BUT SINCE THEY ARE AT THE BOTTOM OF THE ENSEMBLE ENVELOPE DECIDED TO KEEP TEMPERATURES NEAR THE ENSEMBLE MEAN WITH A GRADUAL COOLING TREND THURSDAY INTO FRIDAY WITH TEMPERATURES RETURNING TO SEASONABLE VALUES FOR THE WEEKEND. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...NONE. OR...NONE. && $$ WEATHER.GOV/BOISE DISCUSSION...VM AVIATION.....AB PREV SHORT TERM...BW PREV LONG TERM....KA/WH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
515 PM CDT FRI APR 24 2015 .SHORT TERM... 323 PM CDT THROUGH SATURDAY NIGHT... SHORT TERM...THROUGH SATURDAY NIGHT... PRIMARY FORECAST CONCERN IS WITH FAIRLY STRONG LOW PRESSURE SYSTEM TRACKING SOUTH OF THE AREA ON SATURDAY AND ASSOCIATED RAIN AND AMOUNTS. DRY AIR MASS REMAINS OVER THE AREA THIS AFTERNOON...BUT WITH GRADUAL MOISTENING FROM BONE DRY CONDITIONS EARLIER TODAY THAT WERE AMONGST DRIEST IN ENTIRE COUNTRY. W/V IMAGERY SHOWS SHORT WAVE/MIDLEVEL SPEED MAX INTO EASTERN IA THAT IS RESULTING IN OCCASIONAL VERY LIGHT RAIN/SPRINKLES REACHING THE GROUND DESPITE LARGE DEWPOINT DEPRESSIONS. SUSPECT THAT HRRR MODEL IS TOO AGGRESSIVE WITH HIGHER REFLECTIVITY/RAIN REACHING THE GROUND SOUTH OF I-88 OR SO AND FOCUS FOR MOST ISOLATED TO SCATTERED ACTIVITY SHOULD BE IN FAR NORTHERN CWA. LATER THIS EVENING INTO THE OVERNIGHT...AREA WILL BE IN BROAD WARM ADVECTION ALOFT BUT ALSO LACKING FOCUS FOR PRECIP WITH MIDLEVEL RIDGING OVERHEAD. SUSPECT THAT THERE WILL BE SEVERAL MAINLY DRY HOURS WITH PERHAPS A FEW ISOLATED SHOWERS. THEN MAIN WAVE WILL START TO SPREAD IN FROM SOUTHWEST AFTER MIDNIGHT INTO SATURDAY MORNING AS CLOSED LOW AND ASSOCIATED SFC LOW MIGRATES ACROSS LOWER MO VALLEY. PRECIP WILL BE FIGHTING DRY EASTERLY LOW LEVEL FLOW ESPECIALLY IN NORTHEAST CWA...BUT THEN AS 700 MB FGEN STRENGTHENS AND TROWAL LIKE FEATURE SPREADS ~1 TO ~1.25 INCH PWATS ACROSS AREA...EXPECTING MID-LATE SATURDAY AM TO BE ACCOMPANIED BY PERIODS OF RAIN/RAIN SHOWERS AND STEADY TO EVEN BRIEFLY HEAVY RATES. VERY MINIMAL ELEVATED INSTABILITY WILL BE PRESENT WELL SOUTH OF I-80...SO HAVE MAINTAINED SLIGHT EMBEDDED THUNDER CHANCES THERE. STILL HAVE HIGH END LIKELY TO CAT POPS IN LATE AFTERNOON...BUT DRIER AIR WORKING IN FROM NORTH SHOULD REDUCE RATES...WITH PRECIP QUICKLY SHIFTING SOUTH DURING EVENING AND SKIES CLEARING TOWARD EARLY SUNDAY. RAIN AMOUNTS FROM MAIN SYSTEM LATE TONIGHT THROUGH SATURDAY SHOULD RANGE FROM ABOUT 1/2 INCH IN FAR NORTHEAST TO A BIT UPWARDS OF ONE INCH IN SOUTHWEST 1/4 TO 1/3 OF CWA. CONFIDENCE IN LOW- MEDIUM IN THESE AMOUNTS GIVEN POTENTIAL FOR BANDING PLACEMENT TO SHIFT. REGARDING TEMPS...INCREASING CLOUDS WILL LIMIT FALL TONIGHT...SO GENERALLY IN 40S TONIGHT EXCEPT UPPER 30S NEAR LAKE COUNTY SHORE. CLOUDS...RAIN AND GUSTY NORTHEAST FLOW WILL MAKE FOR RAW CONDITIONS ON SATURDAY AND HIGHS ONLY RECOVERING TO THE LOW/MID 40S TO LOWER 50S...COOLEST ON ILLINOIS SHORE AND WARMEST SOUTH OF I-80. TEMPS WILL THEN DIP BACK TO THE 30S BY EARLY SUNDAY WITH H8 TEMPS FALLING TO JUST BELOW 0 CELSIUS. EXPECTING SOME NORTHERN INTERIOR LOCATIONS TO DIP TO AROUND FREEZING. OVERALL IT WILL BE ANOTHER NIGHT TO PROTECT COLD SENSITIVE VEGETATION. RC && .LONG TERM... 333 PM CDT SUNDAY THROUGH FRIDAY... EXTENDED PERIOD THROUGH AT LEAST THURSDAY WILL BE DOMINATED BY ONSHORE FLOW AND COOLER CONDITIONS NEAR THE LAKE...BUT ALSO GRADUAL WARMING INLAND. WITH POSSIBLY MINOR EXCEPTION OF WEDNESDAY...CONDITIONS SHOULD BE PRIMARILY DRY AS WELL. AIRMASS WILL BE COOLEST SUNDAY THROUGH EARLY MONDAY...WITH ONLY MID-UPPER 40S ALONG SHORE AND MID-UPPER 50S INLAND AND THEN OVERNIGHT LOWS SUNDAY NIGHT AWAY FROM CHICAGO HEAT ISLAND IN LOWER-MID 30S. AS HIGH PRESSURE DROPS SOUTHEAST TOWARD EARLY MONDAY...WINDS MAY DIMINISH ENOUGH TO SUPPORT AT LEAST PATCHY FROST...BUT HAVE NOT ADDED IT TO GRIDS YET. INLAND HIGHS SHOULD BE INTO THE 60S EACH DAY MON-THU AND TEMPS COULD APPROACH 70 NEXT FRIDAY. RC && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * EAST-NORTHEAST WINDS AROUND 10 KT GRADUALLY INCREASING LATER TONIGHT AND SATURDAY MORNING. * AREA OF LIGHT RAIN EXPECTED TO MOVE IN BY 00Z...WITH GREATEST COVERAGE FROM ORD NORTH. UPSTREAM CONDITIONS INDICATE VFR CIGS WITH OCNL MVFR VIS WITH RA/SHRA. RAIN LINGERING THROUGH 03Z OR SO WITH A LULL POSSIBLE AFTER THAT. * RAIN SPREADING OVER DURING THE MID TO LATE MORNING ON SATURDAY WITH IFR CONDITIONS DEVELOPING A FEW HOURS AFTER ONSET. //DISCUSSION...UPDATED 18Z... SOUTH-SOUTHEAST WINDS ARE GRADUALLY INCREASING ACROSS THE REGION AS HIGH PRESSURE DEPARTS. ON THE LOCAL SCALE...A LAKE BREEZE IS SEEN ON OBSERVATIONAL DATA INCHING WESTWARD ACROSS NORTHEAST ILLINOIS. WITH THE DEEP MIXING THAT HAS OCCURRED OVER LAND...THAT WILL LIKELY CAUSE THE LAKE BREEZE TO FLUCTUATE SOME IN SPEED. MOISTURE WILL SLOWLY RETURN AS LOW PRESSURE CONTINUES TO ORGANIZE IN THE CENTRAL PLAINS. THE EXTREME LOW-LEVEL DRYNESS WILL INITIALLY PREVENT RADAR ECHOES FROM MATERIALIZING AS RAIN SHOWERS THIS AFTERNOON OVER CHICAGO AIRPORTS...THOUGH SOME SPOTTY LIGHT RAIN WILL LIKELY BE SEEN NEAR OR AT RFD LATER TODAY. AFTER DARK...AS A WEAK UPPER DISTURBANCE MOVES ACROSS FAR SOUTHERN WISCONSIN...LIGHT SHOWERS MAY MOVE NEAR/OVER THE CHICAGOLAND TAF SITES. THE PRIMARY PERIOD OF RAIN CONTINUES TO LOOK LIKE SATURDAY THOUGH HAVE SLOWED THE ONSET TIME IN THE FORECAST UNTIL THE PROJECTED STRONGER FORCING ARRIVES. THIS LOOKS TO BE MID TO LATE MORNING. IFR CIGS AND AT LEAST TEMPORARY VISIBILITY OF 3SM OR LOWER CAN BE EXPECTED DURING THE MODERATE RAIN. EASTERLY WINDS WILL PREVAIL THROUGH THIS TIME GIVEN LOW PRESSURE TO THE SOUTH OF THE AREA. //ORD AND MDW CONFIDENCE...UPDATED 22Z... * MEDIUM-HIGH IN WINDS. * MEDIUM-HIGH IN PERIOD OF LIGHT RAIN/SHOWERS STARTING AROUND 00Z ESPECIALLY FROM ORD NORTH AND WEST. MEDIUM HIGH IN VFR CIGS AND VFR/MVFR VIS IN HEAVIER SHOWERS. * HIGH IN IFR CONDITIONS IN RAIN ON SATURDAY. MEDIUM IN TIMING. //OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z... * SATURDAY NIGHT THROUGH THURSDAY...VFR WITH PRIMARILY NORTHEASTERLY WINDS. MTF/RATZER && .MARINE... 215 PM CDT HIGH PRESSURE MOVING ACROSS THE CENTRAL GREAT LAKES REGION HAS SET UP GENERALLY LIGHT AND VARIABLE WINDS OVER LAKE MICHIGAN. THE LIGHT WINDS REGIME AND LAND-LAKE DIFFERENTIAL HEATING HAS SET UP A LAKE BREEZE WITH NEARSHORE WINDS TAKING AN ONSHORE ORIENTATION THIS AFTERNOON. AS THE HIGH MOVES OFF TO THE EAST TONIGHT...LOW PRESSURE OVER THE CENTRAL PLAINS WILL DEEPEN AND MOVE EAST TO NWRN MO OVERNIGHT TONIGHT. A DEVELOPING WARM FRONT WILL EXTEND EAST FROM THE LOW ACROSS CNTRL IL/IN...WITH WINDS BECOMING EASTERLY BY LATE TONIGHT. THE WARM FRONT IS EXPECTED TO REMAIN NEARLY STATIONARY AS THE LOW TRACKS EWD...KEEPING WINDS OVER THE LAKE ELY. AS THE LOW PASSES SOUTH OF THE LAKE AND A RIDGE OF HIGH PRESSURE BUILDS FROM HUDSON BAY THROUGH THE NRN GREAT LAKES...WIND SPEEDS WILL INCREASE WITH THE STRONGEST WINDS OF 25-30 KT OVER THE SRN PORTIONS OF THE LAKE. AS THE LOW PASSES EAST THROUGH THE OHIO VALLEY SATURDAY NIGHT INTO SUNDAY MORNING...WINDS WILL BACK TO NORTHERLY. WHILE GALES ARE NOT LIKELY...WINDS OVER THE SRN PORTIONS OF THE LAKE WILL BE STRONG ENOUGH TO REQUIRE A SMALL CRAFT ADVISORY AND EVEN THOUGH WINDS SHOULD WEAKEN BELOW SMALL CRAFT ADVISORY LEVELS WITH THE SHIFT TO NORTHERLY...THE LONG FETCH SHOULD BE SUFFICIENT TO KEEP SMALL CRAFT ADVISORY LEVEL WAVES INTO MONDAY MORNING. HIGH PRESSURE WILL BUILD ACROSS THE LAKE BY TUESDAY MORNING AND REMAIN THE DOMINANT FEATURE THROUGH MUCH OF NEXT WEEK...SETTING A PERIOD OF RELATIVELY QUIET CONDITIONS OVER THE LAKE FROM TUESDAY THROUGH THE END OF THE FORECAST PERIOD. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
334 PM CDT FRI APR 24 2015 .SHORT TERM... 323 PM CDT THROUGH SATURDAY NIGHT... SHORT TERM...THROUGH SATURDAY NIGHT... PRIMARY FORECAST CONCERN IS WITH FAIRLY STRONG LOW PRESSURE SYSTEM TRACKING SOUTH OF THE AREA ON SATURDAY AND ASSOCIATED RAIN AND AMOUNTS. DRY AIR MASS REMAINS OVER THE AREA THIS AFTERNOON...BUT WITH GRADUAL MOISTENING FROM BONE DRY CONDITIONS EARLIER TODAY THAT WERE AMONGST DRIEST IN ENTIRE COUNTRY. W/V IMAGERY SHOWS SHORT WAVE/MIDLEVEL SPEED MAX INTO EASTERN IA THAT IS RESULTING IN OCCASIONAL VERY LIGHT RAIN/SPRINKLES REACHING THE GROUND DESPITE LARGE DEWPOINT DEPRESSIONS. SUSPECT THAT HRRR MODEL IS TOO AGGRESSIVE WITH HIGHER REFLECTIVITY/RAIN REACHING THE GROUND SOUTH OF I-88 OR SO AND FOCUS FOR MOST ISOLATED TO SCATTERED ACTIVITY SHOULD BE IN FAR NORTHERN CWA. LATER THIS EVENING INTO THE OVERNIGHT...AREA WILL BE IN BROAD WARM ADVECTION ALOFT BUT ALSO LACKING FOCUS FOR PRECIP WITH MIDLEVEL RIDGING OVERHEAD. SUSPECT THAT THERE WILL BE SEVERAL MAINLY DRY HOURS WITH PERHAPS A FEW ISOLATED SHOWERS. THEN MAIN WAVE WILL START TO SPREAD IN FROM SOUTHWEST AFTER MIDNIGHT INTO SATURDAY MORNING AS CLOSED LOW AND ASSOCIATED SFC LOW MIGRATES ACROSS LOWER MO VALLEY. PRECIP WILL BE FIGHTING DRY EASTERLY LOW LEVEL FLOW ESPECIALLY IN NORTHEAST CWA...BUT THEN AS 700 MB FGEN STRENGTHENS AND TROWAL LIKE FEATURE SPREADS ~1 TO ~1.25 INCH PWATS ACROSS AREA...EXPECTING MID-LATE SATURDAY AM TO BE ACCOMPANIED BY PERIODS OF RAIN/RAIN SHOWERS AND STEADY TO EVEN BRIEFLY HEAVY RATES. VERY MINIMAL ELEVATED INSTABILITY WILL BE PRESENT WELL SOUTH OF I-80...SO HAVE MAINTAINED SLIGHT EMBEDDED THUNDER CHANCES THERE. STILL HAVE HIGH END LIKELY TO CAT POPS IN LATE AFTERNOON...BUT DRIER AIR WORKING IN FROM NORTH SHOULD REDUCE RATES...WITH PRECIP QUICKLY SHIFTING SOUTH DURING EVENING AND SKIES CLEARING TOWARD EARLY SUNDAY. RAIN AMOUNTS FROM MAIN SYSTEM LATE TONIGHT THROUGH SATURDAY SHOULD RANGE FROM ABOUT 1/2 INCH IN FAR NORTHEAST TO A BIT UPWARDS OF ONE INCH IN SOUTHWEST 1/4 TO 1/3 OF CWA. CONFIDENCE IN LOW- MEDIUM IN THESE AMOUNTS GIVEN POTENTIAL FOR BANDING PLACEMENT TO SHIFT. REGARDING TEMPS...INCREASING CLOUDS WILL LIMIT FALL TONIGHT...SO GENERALLY IN 40S TONIGHT EXCEPT UPPER 30S NEAR LAKE COUNTY SHORE. CLOUDS...RAIN AND GUSTY NORTHEAST FLOW WILL MAKE FOR RAW CONDITIONS ON SATURDAY AND HIGHS ONLY RECOVERING TO THE LOW/MID 40S TO LOWER 50S...COOLEST ON ILLINOIS SHORE AND WARMEST SOUTH OF I-80. TEMPS WILL THEN DIP BACK TO THE 30S BY EARLY SUNDAY WITH H8 TEMPS FALLING TO JUST BELOW 0 CELSIUS. EXPECTING SOME NORTHERN INTERIOR LOCATIONS TO DIP TO AROUND FREEZING. OVERALL IT WILL BE ANOTHER NIGHT TO PROTECT COLD SENSITIVE VEGETATION. RC && .LONG TERM... 333 PM CDT SUNDAY THROUGH FRIDAY... EXTENDED PERIOD THROUGH AT LEAST THURSDAY WILL BE DOMINATED BY ONSHORE FLOW AND COOLER CONDITIONS NEAR THE LAKE...BUT ALSO GRADUAL WARMING INLAND. WITH POSSIBLY MINOR EXCEPTION OF WEDNESDAY...CONDITIONS SHOULD BE PRIMARILY DRY AS WELL. AIRMASS WILL BE COOLEST SUNDAY THROUGH EARLY MONDAY...WITH ONLY MID-UPPER 40S ALONG SHORE AND MID-UPPER 50S INLAND AND THEN OVERNIGHT LOWS SUNDAY NIGHT AWAY FROM CHICAGO HEAT ISLAND IN LOWER-MID 30S. AS HIGH PRESSURE DROPS SOUTHEAST TOWARD EARLY MONDAY...WINDS MAY DIMINISH ENOUGH TO SUPPORT AT LEAST PATCHY FROST...BUT HAVE NOT ADDED IT TO GRIDS YET. INLAND HIGHS SHOULD BE INTO THE 60S EACH DAY MON-THU AND TEMPS COULD APPROACH 70 NEXT FRIDAY. RC && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * EAST-NORTHEAST WINDS AROUND 10 KT GRADUALLY INCREASING LATER TONIGHT AND SATURDAY MORNING. * SCATTERED LIGHT RAIN SHOWERS AT LEAST NEARBY THROUGH 03Z OR SO. * RAIN SPREADING OVER DURING THE MID TO LATE MORNING ON SATURDAY WITH IFR CONDITIONS DEVELOPING A FEW HOURS AFTER ONSET. //DISCUSSION...UPDATED 18Z... SOUTH-SOUTHEAST WINDS ARE GRADUALLY INCREASING ACROSS THE REGION AS HIGH PRESSURE DEPARTS. ON THE LOCAL SCALE...A LAKE BREEZE IS SEEN ON OBSERVATIONAL DATA INCHING WESTWARD ACROSS NORTHEAST ILLINOIS. WITH THE DEEP MIXING THAT HAS OCCURRED OVER LAND...THAT WILL LIKELY CAUSE THE LAKE BREEZE TO FLUCTUATE SOME IN SPEED. MOISTURE WILL SLOWLY RETURN AS LOW PRESSURE CONTINUES TO ORGANIZE IN THE CENTRAL PLAINS. THE EXTREME LOW-LEVEL DRYNESS WILL INITIALLY PREVENT RADAR ECHOES FROM MATERIALIZING AS RAIN SHOWERS THIS AFTERNOON OVER CHICAGO AIRPORTS...THOUGH SOME SPOTTY LIGHT RAIN WILL LIKELY BE SEEN NEAR OR AT RFD LATER TODAY. AFTER DARK...AS A WEAK UPPER DISTURBANCE MOVES ACROSS FAR SOUTHERN WISCONSIN...LIGHT SHOWERS MAY MOVE NEAR/OVER THE CHICAGOLAND TAF SITES. THE PRIMARY PERIOD OF RAIN CONTINUES TO LOOK LIKE SATURDAY THOUGH HAVE SLOWED THE ONSET TIME IN THE FORECAST UNTIL THE PROJECTED STRONGER FORCING ARRIVES. THIS LOOKS TO BE MID TO LATE MORNING. IFR CIGS AND AT LEAST TEMPORARY VISIBILITY OF 3SM OR LOWER CAN BE EXPECTED DURING THE MODERATE RAIN. EASTERLY WINDS WILL PREVAIL THROUGH THIS TIME GIVEN LOW PRESSURE TO THE SOUTH OF THE AREA. //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM-HIGH IN WINDS. * LOW-MEDIUM IN SCATTERED LIGHT RAIN SHOWERS THROUGH MID-EVENING. HIGH THAT IF ANY SHOWERS OCCUR THEY WILL BE LIGHT WITH VFR CONDITIONS. * HIGH IN IFR CONDITIONS IN RAIN ON SATURDAY. MEDIUM IN TIMING. //OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z... * SATURDAY NIGHT THROUGH THURSDAY...VFR WITH PRIMARILY NORTHEASTERLY WINDS. MTF && .MARINE... 215 PM CDT HIGH PRESSURE MOVING ACROSS THE CENTRAL GREAT LAKES REGION HAS SET UP GENERALLY LIGHT AND VARIABLE WINDS OVER LAKE MICHIGAN. THE LIGHT WINDS REGIME AND LAND-LAKE DIFFERENTIAL HEATING HAS SET UP A LAKE BREEZE WITH NEARSHORE WINDS TAKING AN ONSHORE ORIENTATION THIS AFTERNOON. AS THE HIGH MOVES OFF TO THE EAST TONIGHT...LOW PRESSURE OVER THE CENTRAL PLAINS WILL DEEPEN AND MOVE EAST TO NWRN MO OVERNIGHT TONIGHT. A DEVELOPING WARM FRONT WILL EXTEND EAST FROM THE LOW ACROSS CNTRL IL/IN...WITH WINDS BECOMING EASTERLY BY LATE TONIGHT. THE WARM FRONT IS EXPECTED TO REMAIN NEARLY STATIONARY AS THE LOW TRACKS EWD...KEEPING WINDS OVER THE LAKE ELY. AS THE LOW PASSES SOUTH OF THE LAKE AND A RIDGE OF HIGH PRESSURE BUILDS FROM HUDSON BAY THROUGH THE NRN GREAT LAKES...WIND SPEEDS WILL INCREASE WITH THE STRONGEST WINDS OF 25-30 KT OVER THE SRN PORTIONS OF THE LAKE. AS THE LOW PASSES EAST THROUGH THE OHIO VALLEY SATURDAY NIGHT INTO SUNDAY MORNING...WINDS WILL BACK TO NORTHERLY. WHILE GALES ARE NOT LIKELY...WINDS OVER THE SRN PORTIONS OF THE LAKE WILL BE STRONG ENOUGH TO REQUIRE A SMALL CRAFT ADVISORY AND EVEN THOUGH WINDS SHOULD WEAKEN BELOW SMALL CRAFT ADVISORY LEVELS WITH THE SHIFT TO NORTHERLY...THE LONG FETCH SHOULD BE SUFFICIENT TO KEEP SMALL CRAFT ADVISORY LEVEL WAVES INTO MONDAY MORNING. HIGH PRESSURE WILL BUILD ACROSS THE LAKE BY TUESDAY MORNING AND REMAIN THE DOMINANT FEATURE THROUGH MUCH OF NEXT WEEK...SETTING A PERIOD OF RELATIVELY QUIET CONDITIONS OVER THE LAKE FROM TUESDAY THROUGH THE END OF THE FORECAST PERIOD. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
324 PM CDT FRI APR 24 2015 .SHORT TERM... 323 PM CDT THROUGH SATURDAY NIGHT... SHORT TERM...THROUGH SATURDAY NIGHT... PRIMARY FORECAST CONCERN IS WITH FAIRLY STRONG LOW PRESSURE SYSTEM TRACKING SOUTH OF THE AREA ON SATURDAY AND ASSOCIATED RAIN AND AMOUNTS. DRY AIR MASS REMAINS OVER THE AREA THIS AFTERNOON...BUT WITH GRADUAL MOISTENING FROM BONE DRY CONDITIONS EARLIER TODAY THAT WERE AMONGST DRIEST IN ENTIRE COUNTRY. W/V IMAGERY SHOWS SHORT WAVE/MIDLEVEL SPEED MAX INTO EASTERN IA THAT IS RESULTING IN OCCASIONAL VERY LIGHT RAIN/SPRINKLES REACHING THE GROUND DESPITE LARGE DEWPOINT DEPRESSIONS. SUSPECT THAT HRRR MODEL IS TOO AGGRESSIVE WITH HIGHER REFLECTIVITY/RAIN REACHING THE GROUND SOUTH OF I-88 OR SO AND FOCUS FOR MOST ISOLATED TO SCATTERED ACTIVITY SHOULD BE IN FAR NORTHERN CWA. LATER THIS EVENING INTO THE OVERNIGHT...AREA WILL BE IN BROAD WARM ADVECTION ALOFT BUT ALSO LACKING FOCUS FOR PRECIP WITH MIDLEVEL RIDGING OVERHEAD. SUSPECT THAT THERE WILL BE SEVERAL MAINLY DRY HOURS WITH PERHAPS A FEW ISOLATED SHOWERS. THEN MAIN WAVE WILL START TO SPREAD IN FROM SOUTHWEST AFTER MIDNIGHT INTO SATURDAY MORNING AS CLOSED LOW AND ASSOCIATED SFC LOW MIGRATES ACROSS LOWER MO VALLEY. PRECIP WILL BE FIGHTING DRY EASTERLY LOW LEVEL FLOW ESPECIALLY IN NORTHEAST CWA...BUT THEN AS 700 MB FGEN STRENGTHENS AND TROWAL LIKE FEATURE SPREADS ~1 TO ~1.25 INCH PWATS ACROSS AREA...EXPECTING MID-LATE SATURDAY AM TO BE ACCOMPANIED BY PERIODS OF RAIN/RAIN SHOWERS AND STEADY TO EVEN BRIEFLY HEAVY RATES. VERY MINIMAL ELEVATED INSTABILITY WILL BE PRESENT WELL SOUTH OF I-80...SO HAVE MAINTAINED SLIGHT EMBEDDED THUNDER CHANCES THERE. STILL HAVE HIGH END LIKELY TO CAT POPS IN LATE AFTERNOON...BUT DRIER AIR WORKING IN FROM NORTH SHOULD REDUCE RATES...WITH PRECIP QUICKLY SHIFTING SOUTH DURING EVENING AND SKIES CLEARING TOWARD EARLY SUNDAY. RAIN AMOUNTS FROM MAIN SYSTEM LATE TONIGHT THROUGH SATURDAY SHOULD RANGE FROM ABOUT 1/2 INCH IN FAR NORTHEAST TO A BIT UPWARDS OF ONE INCH IN SOUTHWEST 1/4 TO 1/3 OF CWA. CONFIDENCE IN LOW- MEDIUM IN THESE AMOUNTS GIVEN POTENTIAL FOR BANDING PLACEMENT TO SHIFT. REGARDING TEMPS...INCREASING CLOUDS WILL LIMIT FALL TONIGHT...SO GENERALLY IN 40S TONIGHT EXCEPT UPPER 30S NEAR LAKE COUNTY SHORE. CLOUDS...RAIN AND GUSTY NORTHEAST FLOW WILL MAKE FOR RAW CONDITIONS ON SATURDAY AND HIGHS ONLY RECOVERING TO THE LOW/MID 40S TO LOWER 50S...COOLEST ON ILLINOIS SHORE AND WARMEST SOUTH OF I-80. TEMPS WILL THEN DIP BACK TO THE 30S BY EARLY SUNDAY WITH H8 TEMPS FALLING TO JUST BELOW 0 CELSIUS. EXPECTING SOME NORTHERN INTERIOR LOCATIONS TO DIP TO AROUND FREEZING. OVERALL IT WILL BE ANOTHER NIGHT TO PROTECT COLD SENSITIVE VEGETATION. RC && .LONG TERM... 323 PM CDT SUNDAY THROUGH FRIDAY... TO BE ISSUED SHORTLY. RC && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * EAST-NORTHEAST WINDS AROUND 10 KT GRADUALLY INCREASING LATER TONIGHT AND SATURDAY MORNING. * SCATTERED LIGHT RAIN SHOWERS AT LEAST NEARBY THROUGH 03Z OR SO. * RAIN SPREADING OVER DURING THE MID TO LATE MORNING ON SATURDAY WITH IFR CONDITIONS DEVELOPING A FEW HOURS AFTER ONSET. //DISCUSSION...UPDATED 18Z... SOUTH-SOUTHEAST WINDS ARE GRADUALLY INCREASING ACROSS THE REGION AS HIGH PRESSURE DEPARTS. ON THE LOCAL SCALE...A LAKE BREEZE IS SEEN ON OBSERVATIONAL DATA INCHING WESTWARD ACROSS NORTHEAST ILLINOIS. WITH THE DEEP MIXING THAT HAS OCCURRED OVER LAND...THAT WILL LIKELY CAUSE THE LAKE BREEZE TO FLUCTUATE SOME IN SPEED. MOISTURE WILL SLOWLY RETURN AS LOW PRESSURE CONTINUES TO ORGANIZE IN THE CENTRAL PLAINS. THE EXTREME LOW-LEVEL DRYNESS WILL INITIALLY PREVENT RADAR ECHOES FROM MATERIALIZING AS RAIN SHOWERS THIS AFTERNOON OVER CHICAGO AIRPORTS...THOUGH SOME SPOTTY LIGHT RAIN WILL LIKELY BE SEEN NEAR OR AT RFD LATER TODAY. AFTER DARK...AS A WEAK UPPER DISTURBANCE MOVES ACROSS FAR SOUTHERN WISCONSIN...LIGHT SHOWERS MAY MOVE NEAR/OVER THE CHICAGOLAND TAF SITES. THE PRIMARY PERIOD OF RAIN CONTINUES TO LOOK LIKE SATURDAY THOUGH HAVE SLOWED THE ONSET TIME IN THE FORECAST UNTIL THE PROJECTED STRONGER FORCING ARRIVES. THIS LOOKS TO BE MID TO LATE MORNING. IFR CIGS AND AT LEAST TEMPORARY VISIBILITY OF 3SM OR LOWER CAN BE EXPECTED DURING THE MODERATE RAIN. EASTERLY WINDS WILL PREVAIL THROUGH THIS TIME GIVEN LOW PRESSURE TO THE SOUTH OF THE AREA. //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM-HIGH IN WINDS. * LOW-MEDIUM IN SCATTERED LIGHT RAIN SHOWERS THROUGH MID-EVENING. HIGH THAT IF ANY SHOWERS OCCUR THEY WILL BE LIGHT WITH VFR CONDITIONS. * HIGH IN IFR CONDITIONS IN RAIN ON SATURDAY. MEDIUM IN TIMING. //OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z... * SATURDAY NIGHT THROUGH THURSDAY...VFR WITH PRIMARILY NORTHEASTERLY WINDS. MTF && .MARINE... 215 PM CDT HIGH PRESSURE MOVING ACROSS THE CENTRAL GREAT LAKES REGION HAS SET UP GENERALLY LIGHT AND VARIABLE WINDS OVER LAKE MICHIGAN. THE LIGHT WINDS REGIME AND LAND-LAKE DIFFERENTIAL HEATING HAS SET UP A LAKE BREEZE WITH NEARSHORE WINDS TAKING AN ONSHORE ORIENTATION THIS AFTERNOON. AS THE HIGH MOVES OFF TO THE EAST TONIGHT...LOW PRESSURE OVER THE CENTRAL PLAINS WILL DEEPEN AND MOVE EAST TO NWRN MO OVERNIGHT TONIGHT. A DEVELOPING WARM FRONT WILL EXTEND EAST FROM THE LOW ACROSS CNTRL IL/IN...WITH WINDS BECOMING EASTERLY BY LATE TONIGHT. THE WARM FRONT IS EXPECTED TO REMAIN NEARLY STATIONARY AS THE LOW TRACKS EWD...KEEPING WINDS OVER THE LAKE ELY. AS THE LOW PASSES SOUTH OF THE LAKE AND A RIDGE OF HIGH PRESSURE BUILDS FROM HUDSON BAY THROUGH THE NRN GREAT LAKES...WIND SPEEDS WILL INCREASE WITH THE STRONGEST WINDS OF 25-30 KT OVER THE SRN PORTIONS OF THE LAKE. AS THE LOW PASSES EAST THROUGH THE OHIO VALLEY SATURDAY NIGHT INTO SUNDAY MORNING...WINDS WILL BACK TO NORTHERLY. WHILE GALES ARE NOT LIKELY...WINDS OVER THE SRN PORTIONS OF THE LAKE WILL BE STRONG ENOUGH TO REQUIRE A SMALL CRAFT ADVISORY AND EVEN THOUGH WINDS SHOULD WEAKEN BELOW SMALL CRAFT ADVISORY LEVELS WITH THE SHIFT TO NORTHERLY...THE LONG FETCH SHOULD BE SUFFICIENT TO KEEP SMALL CRAFT ADVISORY LEVEL WAVES INTO MONDAY MORNING. HIGH PRESSURE WILL BUILD ACROSS THE LAKE BY TUESDAY MORNING AND REMAIN THE DOMINANT FEATURE THROUGH MUCH OF NEXT WEEK...SETTING A PERIOD OF RELATIVELY QUIET CONDITIONS OVER THE LAKE FROM TUESDAY THROUGH THE END OF THE FORECAST PERIOD. KREIN && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS GOODLAND KS
435 PM MDT FRI APR 24 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 201 PM MDT FRI APR 24 2015 AT 1PM MDT VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOWED PARTLY TO MOSTLY CLOUDY SKIES FOR LOCATIONS ACROSS THE TRI STATE AREA WEST OF HIGHWAY 83...WITH LOWER BROKEN TO OVERCAST CONDITIONS EAST OF THE HIGHWAY AHEAD OF AN ADVANCING WARM FRONTAL BOUNDARY. CUMULUS DEVELOPMENT WAS BEGINNING TO DEVELOP ON RADAR AND SATELLITE IMAGERY ALONG A TROUGH/DRY LINE IN EASTERN COLORADO. RAP AND WATER VAPOR IMAGERY SHOWED AN UPPER LEVEL SHORTWAVE TROUGH BEGINNING TO TAKE A NEGATIVE TILT INTO THE CENTRAL AND SOUTHER HIGH PLAINS. THE LATEST HRRR GUIDANCE WAS SHOWING CONVECTIVE INITIATION AT 20Z...ALTHOUGH CELLS ARE ALREADY BEGINNING TO DEVELOP. NMM AND ARW GUIDANCE IS ALSO A BIT BEHIND REALITY WITH HAVING CONVECTION DEVELOP BETWEEN 21Z AND 00Z. 0-1 KM AND 0-3 KM HELICITY WAS NOT IMPRESSIVE WITH WIDESPREAD VALUES UNDER 50 FOR THE FORECAST AREA...SO NOT EXPECTING TORNADOES TO BE A WIDESPREAD THREAT THIS AFTERNOON WITH DEVELOPING STORMS. HOWEVER...0-6 KM BULK SHEAR APPROACHING 35-40 KTS ACROSS THE AREA IN COMBINATION WITH 1500 J/KG OF CAPE SUGGESTS A LARGE HAIL THREAT. WITH DCAPE VALUES MOSTLY BETWEEN 400 AND 500 J/KG...ISOLATED SEVERE WIND GUSTS FROM STORMS IS POSSIBLE...BUT EXPECTING THUNDERSTORMS THIS AFTERNOON TO PRIMARILY HAVE A LARGE HAIL THREAT. STORMS WILL GET GOING BY MID AFTERNOON AND LAST THROUGH THE EVENING. CLOUD COVER WILL BE PRESENT LATE THIS EVENING DUE TO A STEADY STREAM OF MOISTURE MOVING INTO THE FORECAST AREA...HOWEVER A SHORTWAVE RIDGE ALOFT WILL BEGIN TO FORM ACROSS THE AREA AND BRING DRIER AIR INTO THE AREA OVERNIGHT. LOW TEMPERATURES WILL BE SLIGHTLY WARMER THAN NORMAL IN THE MID TO UPPER 40S. DRY AND WARM CONDITIONS WILL BE PRESENT TOMORROW WITH THE SHORTWAVE UPPER LEVEL RIDGE THAT WILL MOVE INTO THE AREA...ALTHOUGH DRY WEATHER WILL BE SHORT LIVED AS ANOTHER TROUGH WITH A CUT OFF LOW FEATURE MOVES INTO THE COLORADO FRONT RANGE AND BRINGS CHANCES FOR SHOWERS AND THUNDERSTORMS. THERE ARE SOME LOCATIONS WITH CAPE VALUES APPROACHING 700 J/KG AND 0-6 BULK SHEAR APPROACHING 35 KTS...HOWEVER FORECAST AREAS IN MODELS DO NOT NECESSARILY LINE UP. THEREFORE...NOT EXPECTING A WIDE SEVERE WEATHER THREAT SATURDAY AFTERNOON...ALTHOUGH AN ISOLATED SEVERE THUNDERSTORM THREAT WILL EXIST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 201 PM MDT FRI APR 24 2015 SATURDAY NIGHT-MONDAY...LARGE SCALE UPPER LOW CLOSES OFF JUST SOUTH OF FOUR CORNERS REGION SATURDAY NIGHT AND MOVES ACROSS THE SOUTHERN PLAINS THROUGH MONDAY NIGHT. A COLD FRONT WILL DROP SOUTH ACROSS THE THE CWA LATE SATURDAY NIGHT AND SUNDAY AND STALL SOUTH AND WEST OF OUR CWA. SOUTHERLY THEN EASTERLY FLOW WILL BRING VERY GOOD MOISTURE ADVECTION INTO OUR CWA AS THIS UPPER LEVEL FEATURE MOVES EAST WITH OVERRUNNING NORTH OF THE STALLED FRONTAL ZONE WHERE ELEVATED FRONT/FRONTOGENETIC FORCING WILL BE IN PLACE. BETTER PRECIP SIGNAL IS CURRENTLY SATURDAY NIGHT THROUGH SUNDAY ACROSS THE WESTERN AND SOUTHWESTERN PART OF THE CWA...WHERE I CONTINUED TREND OF RAISING POPS. IT STILL LOOKS LIKE WE COULD SEE LIGHT PRECIP PERSIST AT LEAST THROUGH LATE SUNDAY NIGHT BEFORE DRIER AIR BEGINS TO ADVECT SOUTH AND SUBSIDENCE BUILDS SOUTHWEST MONDAY. IF CURRENT SIGNAL/TREND CONTINUE I COULD SEE RAISING POPS TO CATEGORICAL LATE SATURDAY NIGHT/SUNDAY...AND TO LIKELY CATEGORY SUNDAY NIGHT THROUGH MONDAY. WHILE 40KM GUIDANCE SHOWS QPF AS FAR EAST AS NORTON/GRAHAM THROUGH THESE PERIODS...PATTERN TENDS TO FAVOR AREAS CLOSER TO FRONTAL ZONE/HIGHER TERRAIN IN COLORADO...SO I KEPT LOWERS POPS NORTHEAST/EAST. IN POST FRONTAL ENVIRONMENT WITH THICK STRATUS/LIKELY PRECIPITATION HIGH TEMPS WILL BE COOLER AND I CONTINUED THE TREND OF LOWER HIGHS ESPECIALLY SUNDAY WHEN HIGHS MAY STRUGGLE TO REACH THE UPPER 40S IN SOME AREAS. MONDAY NIGHT-FRIDAY...THERE IS A SECONDARY H3 JET ROTATING THROUGH THE NORTHERN PLAINS BEHIND THE LARGE SCALE TROUGH...AND THIS COULD BRING ANOTHER QUICK SHOT OF LIGHT SHOWERS....OTHERWISE LARGE SCALE RIDGING WILL BRING DRY CONDITIONS AND A WARMING TREND BACK TO THE REGION THROUGH THURSDAY. MUCH WARMER CONDITIONS ARE EXPECTED BY NEXT FRIDAY (80S) AS LEE TROUGH STRENGTHENS. WHILE THERE ISN`T A LOT OF AGREEMENT AT THIS RANGE THE PATTERN DOES SUPPORT POSSIBLE AFTERNOON/EVENING THUNDERSTORM DEVELOPMENT IN THE HIGHER TERRAIN IN COLORADO MOVING EAST INTO THE WESTERN PORTIONS OF OUR CWA...SO SLIGHT CHANCE POPS WERE KEPT IN PLACE FRIDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 430 PM MDT FRI APR 24 2015 KGLD...VFR THROUGH THE PERIOD. THROUGH 01Z OR 02Z WINDS GENERALLY FROM THE NORTHEAST 5-10KTS BUT WITH VARIOUS OUTFLOW BOUNDARIES FROM THUNDERSTORMS ERRATIC AND GUSTY WINDS POSSIBLE. 02Z-14Z WINDS FROM THE WEST NEAR 10KTS WITH ONLY A FEW CLOUDS EXPECTED. 14Z-18Z WINDS VEER TO THE NORTHWEST AROUND 12KTS WITH SKC CONDITIONS EXPECTED. 18Z THROUGH THE REST OF THE TAF PERIOD WINDS CONTINUE TO VEER TO THE NORTH (18Z) THEN NORTHEAST (22Z) AT 11KTS OR LESS. MAY SEE A FEW CU DEVELOP AROUND 18Z BUT MORE LIKELY LATER IN THE AFTERNOON AS A WEATHER DISTURBANCE APPROACHES FROM THE WEST. KMCK...VFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH 05Z WINDS VARIABLE WINDS 6KTS OR LESS. 06Z-15Z MODELS HINT AT SOME LOW LEVEL MOISTURE IN THE BOUNDARY LAYER THAT MAY BE ENOUGH TO PRODUCE A SCATTERED TO BROKEN DECK. FOR NOW HAVE A SCATTERED DECK. WINDS BECOMING NORTHWEST 5-10KTS. 16Z THROUGH THE REST OF THE TAF PERIOD AM EXPECTING NORTHWEST WINDS TO VEER TO THE NORTHEAST THEN EAST- NORTHEAST UNDER 10KTS. SHOULD SEE A BROKEN DECK OF CLOUDS AROUND 4K FT FOR MUCH OF THE PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...MK LONG TERM...DR AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
203 PM MDT FRI APR 24 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 201 PM MDT FRI APR 24 2015 AT 1PM MDT VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOWED PARTLY TO MOSTLY CLOUDY SKIES FOR LOCATIONS ACROSS THE TRI STATE AREA WEST OF HIGHWAY 83...WITH LOWER BROKEN TO OVERCAST CONDITIONS EAST OF THE HIGHWAY AHEAD OF AN ADVANCING WARM FRONTAL BOUNDARY. CUMULUS DEVELOPMENT WAS BEGINNING TO DEVELOP ON RADAR AND SATELLITE IMAGERY ALONG A TROUGH/DRY LINE IN EASTERN COLORADO. RAP AND WATER VAPOR IMAGERY SHOWED AN UPPER LEVEL SHORTWAVE TROUGH BEGINNING TO TAKE A NEGATIVE TILT INTO THE CENTRAL AND SOUTHER HIGH PLAINS. THE LATEST HRRR GUIDANCE WAS SHOWING CONVECTIVE INITIATION AT 20Z...ALTHOUGH CELLS ARE ALREADY BEGINNING TO DEVELOP. NMM AND ARW GUIDANCE IS ALSO A BIT BEHIND REALITY WITH HAVING CONVECTION DEVELOP BETWEEN 21Z AND 00Z. 0-1 KM AND 0-3 KM HELICITY WAS NOT IMPRESSIVE WITH WIDESPREAD VALUES UNDER 50 FOR THE FORECAST AREA...SO NOT EXPECTING TORNADOES TO BE A WIDESPREAD THREAT THIS AFTERNOON WITH DEVELOPING STORMS. HOWEVER...0-6 KM BULK SHEAR APPROACHING 35-40 KTS ACROSS THE AREA IN COMBINATION WITH 1500 J/KG OF CAPE SUGGESTS A LARGE HAIL THREAT. WITH DCAPE VALUES MOSTLY BETWEEN 400 AND 500 J/KG...ISOLATED SEVERE WIND GUSTS FROM STORMS IS POSSIBLE...BUT EXPECTING THUNDERSTORMS THIS AFTERNOON TO PRIMARILY HAVE A LARGE HAIL THREAT. STORMS WILL GET GOING BY MID AFTERNOON AND LAST THROUGH THE EVENING. CLOUD COVER WILL BE PRESENT LATE THIS EVENING DUE TO A STEADY STREAM OF MOISTURE MOVING INTO THE FORECAST AREA...HOWEVER A SHORTWAVE RIDGE ALOFT WILL BEGIN TO FORM ACROSS THE AREA AND BRING DRIER AIR INTO THE AREA OVERNIGHT. LOW TEMPERATURES WILL BE SLIGHTLY WARMER THAN NORMAL IN THE MID TO UPPER 40S. DRY AND WARM CONDITIONS WILL BE PRESENT TOMORROW WITH THE SHORTWAVE UPPER LEVEL RIDGE THAT WILL MOVE INTO THE AREA...ALTHOUGH DRY WEATHER WILL BE SHORT LIVED AS ANOTHER TROUGH WITH A CUT OFF LOW FEATURE MOVES INTO THE COLORADO FRONT RANGE AND BRINGS CHANCES FOR SHOWERS AND THUNDERSTORMS. THERE ARE SOME LOCATIONS WITH CAPE VALUES APPROACHING 700 J/KG AND 0-6 BULK SHEAR APPROACHING 35 KTS...HOWEVER FORECAST AREAS IN MODELS DO NOT NECESSARILY LINE UP. THEREFORE...NOT EXPECTING A WIDE SEVERE WEATHER THREAT SATURDAY AFTERNOON...ALTHOUGH AN ISOLATED SEVERE THUNDERSTORM THREAT WILL EXIST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 201 PM MDT FRI APR 24 2015 SATURDAY NIGHT-MONDAY...LARGE SCALE UPPER LOW CLOSES OFF JUST SOUTH OF FOUR CORNERS REGION SATURDAY NIGHT AND MOVES ACROSS THE SOUTHERN PLAINS THROUGH MONDAY NIGHT. A COLD FRONT WILL DROP SOUTH ACROSS THE THE CWA LATE SATURDAY NIGHT AND SUNDAY AND STALL SOUTH AND WEST OF OUR CWA. SOUTHERLY THEN EASTERLY FLOW WILL BRING VERY GOOD MOISTURE ADVECTION INTO OUR CWA AS THIS UPPER LEVEL FEATURE MOVES EAST WITH OVERRUNNING NORTH OF THE STALLED FRONTAL ZONE WHERE ELEVATED FRONT/FRONTOGENETIC FORCING WILL BE IN PLACE. BETTER PRECIP SIGNAL IS CURRENTLY SATURDAY NIGHT THROUGH SUNDAY ACROSS THE WESTERN AND SOUTHWESTERN PART OF THE CWA...WHERE I CONTINUED TREND OF RAISING POPS. IT STILL LOOKS LIKE WE COULD SEE LIGHT PRECIP PERSIST AT LEAST THROUGH LATE SUNDAY NIGHT BEFORE DRIER AIR BEGINS TO ADVECT SOUTH AND SUBSIDENCE BUILDS SOUTHWEST MONDAY. IF CURRENT SIGNAL/TREND CONTINUE I COULD SEE RAISING POPS TO CATEGORICAL LATE SATURDAY NIGHT/SUNDAY...AND TO LIKELY CATEGORY SUNDAY NIGHT THROUGH MONDAY. WHILE 40KM GUIDANCE SHOWS QPF AS FAR EAST AS NORTON/GRAHAM THROUGH THESE PERIODS...PATTERN TENDS TO FAVOR AREAS CLOSER TO FRONTAL ZONE/HIGHER TERRAIN IN COLORADO...SO I KEPT LOWERS POPS NORTHEAST/EAST. IN POST FRONTAL ENVIRONMENT WITH THICK STRATUS/LIKELY PRECIPITATION HIGH TEMPS WILL BE COOLER AND I CONTINUED THE TREND OF LOWER HIGHS ESPECIALLY SUNDAY WHEN HIGHS MAY STRUGGLE TO REACH THE UPPER 40S IN SOME AREAS. MONDAY NIGHT-FRIDAY...THERE IS A SECONDARY H3 JET ROTATING THROUGH THE NORTHERN PLAINS BEHIND THE LARGE SCALE TROUGH...AND THIS COULD BRING ANOTHER QUICK SHOT OF LIGHT SHOWERS....OTHERWISE LARGE SCALE RIDGING WILL BRING DRY CONDITIONS AND A WARMING TREND BACK TO THE REGION THROUGH THURSDAY. MUCH WARMER CONDITIONS ARE EXPECTED BY NEXT FRIDAY (80S) AS LEE TROUGH STRENGTHENS. WHILE THERE ISN`T A LOT OF AGREEMENT AT THIS RANGE THE PATTERN DOES SUPPORT POSSIBLE AFTERNOON/EVENING THUNDERSTORM DEVELOPMENT IN THE HIGHER TERRAIN IN COLORADO MOVING EAST INTO THE WESTERN PORTIONS OF OUR CWA...SO SLIGHT CHANCE POPS WERE KEPT IN PLACE FRIDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1134 AM MDT FRI APR 24 2015 IN THE IMMEDIATE TERM FOR KMCK...A PESKY LAYER OF MVFR OVERCAST SKIES WILL CONTINUE FOR THE EARLY AFTERNOON HOURS. LOWER CEILINGS SHOULD IMPROVE MY MID AFTERNOON. AN APPROACHING UPPER LEVEL DISTURBANCE WILL BRING SHOWERS AND THUNDERSTORMS IN THE VICINITY OF THE TAF SITES THIS AFTERNOON. DUE TO LACK OF CONFIDENCE IN THE EXACT TRACK OF THE STORMS...ONLY PUT VCTS MENTION IN THE FORECAST. OVERCAST SKIES WILL BE PRESENT OVERNIGHT UNTIL THE MORNING HOURS WHEN SKIES BEGIN TO CLEAR. VFR CONDITIONS WILL PREVAIL FOR BOTH KMCK AND KGLD OVERNIGHT THROUGH THE END OF THE TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...MK LONG TERM...DR AVIATION...MK
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
111 PM CDT FRI APR 24 2015 ...UPDATED LONG TERM DISCUSSION... .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 1234 PM CDT FRI APR 24 2015 THE SHORT-FUSE SEVERE WEATHER COMPOSITE AT MIDDAY WAS SHOWING A THREAT AREA STARTING TO DEVELOP ALONG THE SLOWLY NORTHWARD ADVANCING WARM FRONT ACROSS WEST-CENTRAL KANSAS. SURFACE-BASED CAPE WAS APPROACHING 1000 J/KG PER LAPS ANALYSIS AS OF 16Z. A SYNOPTIC DRY INTRUSION/DRYLINE WILL CONTINUE TO ADVANCE NORTHEASTWARD, SHUNTING THE SURFACE-BASED INGREDIENTS FOR SEVERE THUNDERSTORMS UP TOWARD THE I-70 CORRIDOR. BY 21Z, THE HRRR INDICATES DEEP MOIST CONVECTION DEVELOPING ALONG THE WARM FRONT BY 20-21Z. THERE SHOULD BE PRETTY GOOD LOW LEVEL SHEAR ALONG THE FRONT WITH AMPLE STREAMWISE VORTICITY TO INGEST INTO AN INCIPIENT SUPERCELL STORM. THE HRRR HAS SHOWN A PERSISTENT LONG-TRACK UPDRAFT HELICITY SIGNAL, WHICH WOULD SUPPORT A FAIRLY LONG-LIVED SUPERCELL THUNDERSTORM. IT CERTAINLY APPEARS THE BEST TORNADO THREAT WILL BE UP ALONG THE FRONT ALONG THE I-70 CORRIDOR, WITH THE MOST VIGOROUS SURFACE-BASED STORMS EXITING OUR AREA OF RESPONSIBILITY (EAST OF ELLIS AND RUSH COUNTY) BY AS SOON AS 23Z. WE WILL HAVE TO WATCH THE BENT-BACK REGION OF ENHANCED CAPE/MOISTURE WESTWARD ALONG I-70 FOR FUTURE GROWTH OF DEEP MOIST CONVECTION AS SOME OF THE LATEST RUNS OF THE HRRR SUGGEST. THERE WILL LIKELY BE A LOCALIZED HEAVY RAIN RISK ALONG THE FRONT UP THERE SHOULD THE HRRR PAN OUT. THE SHORTWAVE TROUGH WILL QUICKLY EXIT THE SOUTHWEST KANSAS REGION BY LATE EVENING WITH SOME WESTERLY LOW LEVEL MOMENTUM FINALLY PUSHING INTO OUR REGION ESPECIALLY AFTER 06Z TONIGHT. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 111 PM CDT FRI APR 24 2015 BY THE BEGINNING OF THE EXTENDED PERIOD, AN UPPER TROUGH WILL BE BE DEEPENING OVER THE WESTERN STATES THANKS TO A 120+ KNOT JET LOCATED ON THE WEST SIDE OF THE TROUGH. THIS TROUGH WILL CONTINUE TO DEEPEN AND CLOSE OFF INTO AN UPPER LOW OVER NEW MEXICO ON SUNDAY BEFORE MOVING OUT ACROSS THE SOUTHERN PLAINS EARLY NEXT WEEK. AS THE TROUGH AND LOW DEVELOP, LOW PRESSURE OVER EASTERN COLORADO WILL DROP SOUTH INTO THE TEXAS PANHANDLE WHILE A COOL FRONT DROPS SOUTH ACROSS WESTERN KANSAS SATURDAY NIGHT. COOL AND MOIST LOW LEVEL EASTERLY FLOW WILL DEVELOP OVER SOUTHWEST KANSAS BEHIND THE FRONT. THIS WILL LEAD TO CLOUDY AND COOLER CONDITIONS ALONG WITH INCREASING CHANCES FOR SHOWERS AND POSSIBLY A FEW THUNDERSTORMS LATE SUNDAY THROUGH THE EARLY PART OF NEXT WEEK. THE MEDIUM RANGE MODELS HAVE BEEN HOLDING ON TO THEIR RESPECTIVE SOLUTIONS REGARDING THE TRACK OF THE UPPER LOW AS IT MOVES OUT THROUGH THE SOUTHERN PLAINS MONDAY AND TUESDAY. THE TRACK OF THE LOW WILL HAVE AN IMPACT ON PRECIPITATION CHANCES AND RAINFALL AMOUNTS ACROSS SOUTHWEST KANSAS. THE GFS CONTINUES TO BE FARTHEST NORTH WITH ITS TRACK ACROSS THE TEXAS PANHANDLE THROUGH OKLAHOMA INTO MISSOURI. THIS MODEL IS SHOWING DECENT RAINFALL ACROSS MUCH OF CENTRAL AND SOUTHWEST KANSAS. BOTH THE ECMWF AND CANADIAN MODELS TRACK THE UPPER LOW OUT ACROSS WESTERN AND NORTHERN TEXAS INTO ARKANSAS AND HAVE THE BEST RAINFALL AMOUNTS CONFINED TO AREAS ALONG AND JUST NORTH OF THE OKLAHOMA BORDER. THE CURRENT FORECAST THROUGH MONDAY LOOKS REASONABLE WITH LIKELY POPS NEAR THE OKLAHOMA BORDER THAT DIMINISH FARTHER NORTH AND HAVE ONLY MADE SOME MINOR ADJUSTMENTS. GIVEN THE CLOUDY, COOL AND MOIST CONDITIONS THAT DEVELOP, HIGH TEMPERATURES ON SUNDAY AND MONDAY WILL LIKELY NOT GET OUT OF THE 50S IN MANY LOCATIONS ESPECIALLY ON MONDAY. THE REMAINDER OF THE EXTENDED PERIOD SHOULD SEE DRIER AND WARMER WEATHER RETURNING AS UPPER LEVEL RIDGING BUILDS BACK OVER THE CENTRAL PLAINS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1234 PM CDT FRI APR 24 2015 SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE COMMON ACROSS SOUTHWEST KANSAS FROM MID AFTERNOON THROUGH LATE THIS EVENING. THE GREATEST SEVERE WEATHER RISK WILL BE CONFINED TO THE HYS TERMINAL, WHERE WE WILL GO WITH A 2-HR TEMPO GROUP OF SEVERE THUNDERSTORMS INCLUDING HAIL, WITH FAIRLY HIGH CONFIDENCE OF OCCURRENCE BASED ON RUN-TO-RUN CONTINUITY FROM THE HRRR MODEL OF A SUPERCELL ALONG THE WARM FRONT. AT GCK AND DDC, THUNDERSTORMS WILL BE IN THE VICINITY ANY TIME AFTER 21Z AND CONTINUING THROUGH MID- EVENING, WITH THE PRECIPITATION MODE BECOMING MORE SHOWERY BY MID TO LATE EVENING PRIOR TO ENDING. && .PRELIMINARY POINT TEMPS/POPS... DDC 50 79 48 62 / 60 10 10 20 GCK 48 78 48 57 / 40 10 10 30 EHA 48 79 47 68 / 20 10 10 30 LBL 49 81 48 68 / 40 10 10 30 HYS 51 73 46 58 / 60 10 20 20 P28 53 81 52 68 / 40 10 10 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...UMSCHEID LONG TERM...GERARD AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1235 PM CDT FRI APR 24 2015 ...UPDATED AVIATION AND SHORT TERM SECTIONS... .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 1234 PM CDT FRI APR 24 2015 THE SHORT-FUSE SEVERE WEATHER COMPOSITE AT MIDDAY WAS SHOWING A THREAT AREA STARTING TO DEVELOP ALONG THE SLOWLY NORTHWARD ADVANCING WARM FRONT ACROSS WEST-CENTRAL KANSAS. SURFACE-BASED CAPE WAS APPROACHING 1000 J/KG PER LAPS ANALYSIS AS OF 16Z. A SYNOPTIC DRY INTRUSION/DRYLINE WILL CONTINUE TO ADVANCE NORTHEASTWARD, SHUNTING THE SURFACE-BASED INGREDIENTS FOR SEVERE THUNDERSTORMS UP TOWARD THE I-70 CORRIDOR. BY 21Z, THE HRRR INDICATES DEEP MOIST CONVECTION DEVELOPING ALONG THE WARM FRONT BY 20-21Z. THERE SHOULD BE PRETTY GOOD LOW LEVEL SHEAR ALONG THE FRONT WITH AMPLE STREAMWISE VORTICITY TO INGEST INTO AN INCIPIENT SUPERCELL STORM. THE HRRR HAS SHOWN A PERSISTENT LONG-TRACK UPDRAFT HELICITY SIGNAL, WHICH WOULD SUPPORT A FAIRLY LONG-LIVED SUPERCELL THUNDERSTORM. IT CERTAINLY APPEARS THE BEST TORNADO THREAT WILL BE UP ALONG THE FRONT ALONG THE I-70 CORRIDOR, WITH THE MOST VIGOROUS SURFACE-BASED STORMS EXITING OUR AREA OF RESPONSIBILITY (EAST OF ELLIS AND RUSH COUNTY) BY AS SOON AS 23Z. WE WILL HAVE TO WATCH THE BENT-BACK REGION OF ENHANCED CAPE/MOISTURE WESTWARD ALONG I-70 FOR FUTURE GROWTH OF DEEP MOIST CONVECTION AS SOME OF THE LATEST RUNS OF THE HRRR SUGGEST. THERE WILL LIKELY BE A LOCALIZED HEAVY RAIN RISK ALONG THE FRONT UP THERE SHOULD THE HRRR PAN OUT. THE SHORTWAVE TROUGH WILL QUICKLY EXIT THE SOUTHWEST KANSAS REGION BY LATE EVENING WITH SOME WESTERLY LOW LEVEL MOMENTUM FINALLY PUSHING INTO OUR REGION ESPECIALLY AFTER 06Z TONIGHT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 255 AM CDT FRI APR 24 2015 MODELS REMAIN IN GOOD AGREEMENT WITH AN UPPER LEVEL SHORT WAVE RIDGE AXIS CROSSING THE CENTRAL HIGH PLAINS EARLY THIS WEEKEND AS A SURFACE COLD FRONT DROPS SOUTH ACROSS SOUTHWEST KANSAS. DESPITE A COLD FRONT CROSSING WESTERN KANSAS DURING THE DAY THE 850MB TEMPERATURES CONTINUE TO SUGGEST TEMPERATURES RANGING FROM THE MID 70S IN WEST CENTRAL AND NORTH CENTRAL KANSAS TO THE LOWER 80S IN SOUTH CENTRAL KANSAS. THIS COLD FRONT WILL MOVE SOUTH OF THE OKLAHOMA BORDER SATURDAY NIGHT WHERE IT IS FORECAST TO BECOME NEARLY STATIONARY THROUGH THE EARLY NEXT WEEK. NORTH OF THIS BOUNDARY A MOIST UPSLOPE FLOW NEAR THE SURFACE AND ISENTROPIC LIFT WILL BEGIN TO IMPROVE ACROSS SOUTHWEST KANSAS AS A DEVELOPING UPPER LOW MOVES SLOWLY EAST ACROSS NEW MEXICO. LOW LEVEL MOISTURE, ISENTROPIC LIFT AND DIFULENT FLOW ALOFT SUNDAY THROUGH EARLY TUESDAY CONTINUES TO SUPPORT IMPROVING CHANCES FOR PRECIPITATION ACROSS SOUTHWEST KANSAS, ESPECIALLY SOUTH OF ROUGHLY A GARDEN CITY TO LARNED LINE SUNDAY NIGHT THROUGH LATE MONDAY IF THE TRACK OF THIS UPPER LOW REMAINS UNCHANGED. CLOUD COVER AND PRECIPITATION CHANCES MONDAY COULD EASILY RESULT IN HIGHS STRUGGLING TO CLIMB MUCH HIGHER THE LOW TO MID 50S NEAR THE OKLAHOMA BORDER. FROM LATE MONDAY INTO EARLY TUESDAY THE UPPER LOW IS FORECAST TO CROSS FROM THE TEXAS PANHANDLE INTO SOUTHEAST OKLAHOMA. AS THIS SYSTEM MOVES SOUTH OF THE OKLAHOMA BORDER LATE MONDAY AND EARLY TUESDAY ISENTROPIC DOWNGLIDE WILL DEVELOP ACROSS SOUTHWEST KANSAS BRINGING AN END TO THE PRECIPITATION CHANCES FROM WEST TO EAST. GUSTY NORTHEAST WINDS WILL ALSO DEVELOP AS COOLER AIR RETURNS TO WESTERN KANSAS. A SURFACE RIDGE AXIS WILL THEN CROSS WESTERN KANSAS MID WEEK WHICH WILL KEEP TEMPERATURES NEAR OR BELOW THE SEASONAL NORMALS FOR THIS TIME OF YEAR. A WARMING TREND WILL THEN BEGIN LATE WEEK AS THE SURFACE HIGH MOVES EAST INTO THE MISSISSIPPI VALLEY AND A SURFACE TROUGH OF LOW PRESSURE DEVELOPS ALONG THE LEE OF THE ROCKIES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1234 PM CDT FRI APR 24 2015 SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL BE COMMON ACROSS SOUTHWEST KANSAS FROM MID AFTERNOON THROUGH LATE THIS EVENING. THE GREATEST SEVERE WEATHER RISK WILL BE CONFINED TO THE HYS TERMINAL, WHERE WE WILL GO WITH A 2-HR TEMPO GROUP OF SEVERE THUNDERSTORMS INCLUDING HAIL, WITH FAIRLY HIGH CONFIDENCE OF OCCURRENCE BASED ON RUN-TO-RUN CONTINUITY FROM THE HRRR MODEL OF A SUPERCELL ALONG THE WARM FRONT. AT GCK AND DDC, THUNDERSTORMS WILL BE IN THE VICINITY ANY TIME AFTER 21Z AND CONTINUING THROUGH MID- EVENING, WITH THE PRECIPITATION MODE BECOMING MORE SHOWERY BY MID TO LATE EVENING PRIOR TO ENDING. && .PRELIMINARY POINT TEMPS/POPS... DDC 81 50 79 48 / 50 60 10 10 GCK 77 48 78 48 / 60 40 10 10 EHA 76 48 79 47 / 30 20 10 10 LBL 80 49 81 48 / 40 40 10 10 HYS 73 51 73 46 / 70 60 10 20 P28 82 53 81 52 / 10 40 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...UMSCHEID LONG TERM...BURGERT AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
620 AM CDT FRI APR 24 2015 ...UPDATED AVIATION DISCUSSION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 354 AM CDT FRI APR 24 2015 A SHARP INCREASE IN SURFACE MOISTURE SHOULD BE NOTICED ACROSS WESTERN KS AS BOUNDARY LAYER MOISTURE TRANSPORT INCREASES IN RESPONSE TO A DEEPENING LEE SURFACE LOW EXPECTED TO TRACK FROM EASTERN CO TO NORTHEAST KS BY LATER TONIGHT. THIS INCREASED SURFACE MOISTURE MIGHT LEAD TO A FEW AREAS OF DRIZZLE AS THE MODELS INDICATE THIS MORNING, BUT MORE IMPORTANTLY CONTRIBUTE TO MUCH HIGHER SURFACE BASED CAPES BY THE EARLY AFTERNOON. A DRYLINE WILL BE PRESENT TO AID IN CONVECTIVE INITIATION AS EARLY AS THE 18 TO 20 UTC TIMEFRAME. WITH RESPECT TO CONVECTIVE THREATS, HAIL WILL BE THE MAIN THREAT AT LEAST EARLY IN THE EVENT. A TORNADO RISK IS ALSO A POSSIBILITY GIVEN THE DEEP SHEAR AND STEEP LOW LEVEL LAPSE RATES/HIGH SURFACE DEW POINTS. THE PARALLEL FLOW TO THE BOUNDARY MIGHT SUGGEST LONG TRACK TORNADOES AREA NOT LIKELY, BUT BRIEF TORNADOES THE MORE LIKELY SCENARIO. ISOLATED, DISCREET STORMS SHOULD BEGIN THE EVENT ALONG THE DRYLINE WITH VERY LARGE HAIL POTENTIAL; EASILY IN THE 2 TO 3 INCH RANGE, AND POTENTIALLY EVEN HIGHER. THE LATEST 4 KM NAM CONVECTIVE SCHEME SUGGESTED THE MORE DISCREET STORMS MORPHING INTO CLUSTER OR SMALL LINES IN CENTRAL KANSAS BY THE EVENING, SUGGESTING POSSIBILITY FOR NOT ONLY SEVERE OUTFLOW, BUT HEAVY RAIN AND LOCALIZED FLOODING. THE UPPER LOW WILL BECOME STACKED SOMEWHERE NEAR KANSAS CITY BY EARLY SATURDAY MORNING, LEAVING WESTERN KANSAS IN A DEEP NORTHWESTERLY FLOW WITH LIGHT WEST SURFACE WINDS. NEGATIVE VORTICITY ADVECTION AND DOWNSLOPE CONDITIONS SHOULD PROMOTE CLEARING SKIES OVERNIGHT INTO SATURDAY MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 255 AM CDT FRI APR 24 2015 MODELS REMAIN IN GOOD AGREEMENT WITH AN UPPER LEVEL SHORT WAVE RIDGE AXIS CROSSING THE CENTRAL HIGH PLAINS EARLY THIS WEEKEND AS A SURFACE COLD FRONT DROPS SOUTH ACROSS SOUTHWEST KANSAS. DESPITE A COLD FRONT CROSSING WESTERN KANSAS DURING THE DAY THE 850MB TEMPERATURES CONTINUE TO SUGGEST TEMPERATURES RANGING FROM THE MID 70S IN WEST CENTRAL AND NORTH CENTRAL KANSAS TO THE LOWER 80S IN SOUTH CENTRAL KANSAS. THIS COLD FRONT WILL MOVE SOUTH OF THE OKLAHOMA BORDER SATURDAY NIGHT WHERE IT IS FORECAST TO BECOME NEARLY STATIONARY THROUGH THE EARLY NEXT WEEK. NORTH OF THIS BOUNDARY A MOIST UPSLOPE FLOW NEAR THE SURFACE AND ISENTROPIC LIFT WILL BEGIN TO IMPROVE ACROSS SOUTHWEST KANSAS AS A DEVELOPING UPPER LOW MOVES SLOWLY EAST ACROSS NEW MEXICO. LOW LEVEL MOISTURE, ISENTROPIC LIFT AND DIFULENT FLOW ALOFT SUNDAY THROUGH EARLY TUESDAY CONTINUES TO SUPPORT IMPROVING CHANCES FOR PRECIPITATION ACROSS SOUTHWEST KANSAS, ESPECIALLY SOUTH OF ROUGHLY A GARDEN CITY TO LARNED LINE SUNDAY NIGHT THROUGH LATE MONDAY IF THE TRACK OF THIS UPPER LOW REMAINS UNCHANGED. CLOUD COVER AND PRECIPITATION CHANCES MONDAY COULD EASILY RESULT IN HIGHS STRUGGLING TO CLIMB MUCH HIGHER THE LOW TO MID 50S NEAR THE OKLAHOMA BORDER. FROM LATE MONDAY INTO EARLY TUESDAY THE UPPER LOW IS FORECAST TO CROSS FROM THE TEXAS PANHANDLE INTO SOUTHEAST OKLAHOMA. AS THIS SYSTEM MOVES SOUTH OF THE OKLAHOMA BORDER LATE MONDAY AND EARLY TUESDAY ISENTROPIC DOWNGLIDE WILL DEVELOP ACROSS SOUTHWEST KANSAS BRINGING AN END TO THE PRECIPITATION CHANCES FROM WEST TO EAST. GUSTY NORTHEAST WINDS WILL ALSO DEVELOP AS COOLER AIR RETURNS TO WESTERN KANSAS. A SURFACE RIDGE AXIS WILL THEN CROSS WESTERN KANSAS MID WEEK WHICH WILL KEEP TEMPERATURES NEAR OR BELOW THE SEASONAL NORMALS FOR THIS TIME OF YEAR. A WARMING TREND WILL THEN BEGIN LATE WEEK AS THE SURFACE HIGH MOVES EAST INTO THE MISSISSIPPI VALLEY AND A SURFACE TROUGH OF LOW PRESSURE DEVELOPS ALONG THE LEE OF THE ROCKIES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 618 AM CDT FRI APR 24 2015 A MOIST UPSLOPE SOUTHEASTERLY FLOW WILL BECOME SOUTHWEST AT 10 TO 15 KNOTS DURING THE DAY AS A WARM FRONT LIFTS NORTH ACROSS SOUTHWEST KANSAS. BASED ON THE 06Z NAM AND THE LATEST HRRR AND RAP THE IFR/LIFR CEILINGS AND AREAS OF MVFR FOG WILL ERODE BETWEEN 13Z AND 16Z AT GCK AND DDC. HYS WILL LIKELY REMAIN IN THE STATUS AND PATCHY FOG UNTIL AROUND 17Z FRIDAY. SCATTERED AFTERNOON THUNDERSTORMS WILL THEN BE POSSIBLE FROM DDC NORTH AND EAST AS AN UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS. GIVEN THE HIGHER PROBABILITY FOR AFTERNOON THUNDERSTORMS AT DDC AND HYS WILL INSERT A PREVAILING PERIOD OF VCTS IN THIS LOCATION. TONIGHT SKIES WILL CLEAR AS SUBSIDENCE DEVELOPS BEHIND THE UPPER LEVEL DISTURBANCE AS MOVES INTO CENTRAL KANSAS. WEST TO NORTHWEST WINDS WILL BE AT 10 TO 15 KNOTS. && .PRELIMINARY POINT TEMPS/POPS... DDC 81 50 79 48 / 50 10 10 10 GCK 77 48 78 48 / 40 10 10 10 EHA 76 48 79 47 / 30 10 10 10 LBL 80 49 81 48 / 30 10 10 10 HYS 73 51 73 46 / 60 50 10 20 P28 82 53 81 52 / 40 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...RUSSELL LONG TERM...BURGERT AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS TOPEKA KS
353 AM CDT Fri Apr 24 2015 .SHORT TERM...(Today and Tonight) Issued at 353 AM CDT FRI APR 24 2015 Upper trough was located over Arizona this morning at 08Z while a weak low pressure tough was located in the lee of the Rockies. Water Vapor loop shows a fetch of moisture extending from the eastern Pacific into the the Central Plains this morning. Low level jet was advecting moisture northward across central Kansas with dew points in the 50s. Expect an increase in low level moisture through the morning hours with low level jet veering to the south southwest. Models are in agreement with the progression of the upper trough into the western Kansas by 00Z then ejecting northeast into northeast Kansas tonight increasing forcing for ascent this evening for convection. The surface low follows a similar track from southwest Kansas into north central and northeast Kansas by late evening. a dry line front will extend south from the low with a warm front lifting northward across the area with much of the area south of I-70 in the warm sector. Initial showers with isolated thunderstorms are possible this morning on the nose of the warm/moisture advection and isentropic lift. Expect a period of little activity from late morning through mid/late afternoon. Later this afternoon expect showers and thunderstorms to develop out in southwest Kansas and into central Kansas then spreading northeast through the evening hours. All of northeast Kansas will have a chance for severe weather from late afternoon into the overnight hours. All modes of severe weather will be possible with large hail, damaging winds and a few tornadoes possible. Soundings show storms remaining surfaced based through much of the evening hours, with backed low level winds and 0-1km helicity of 200-300 m^2/s^2 in the warm sector as well as along the warm front so the tornado threat will likely continue after dark. Threat of storms will diminish gradually after midnight with the passage of the upper trough. Highs today will range from the mid 60s to lower 70s. Lows tonight in the 50s. .LONG TERM...(Saturday through Thursday) Issued at 353 AM CDT FRI APR 24 2015 Upper trough`s exit across northern Missouri brings a gradual end to precip Saturday. Cold air advection on north to northeast winds behind the system brings a modest boundary south through the area in the afternoon, though meager moisture and rising heights preclude any mention of convection. Weak high pressure to the north and a deepening low over the Southwest keeps east winds in place for Sunday. Cloud cover looks rather prevalent for the morning but mixing deep enough to still realize highs in the lower 60s. Still appears the upstream system will stay south of the area into the work week, but at this point will keep small PoPs in the south Sunday night into Monday night. Western ConUS/Rockies ridging dominates conditions through the end of the forecast for high confidence in dry weather. Main challenge should be temperatures with still some influence of eastern Canadian trough not far away, but moderation is likely for at least Tuesday and Wednesday. && .AVIATION...(For the 06Z TAFs through 06Z Friday Night) Issued at 1142 PM CDT THU APR 23 2015 Forecast seems to be on track, so there are not a lot of changes to the prev forecast. Still looks like there is a chance for elevated showers and thunderstorms with it being tough to pin point timing and location. Therefore continue with VCTS. There is a little more uncertainty in how long MVFR CIGS hang in through the day Friday. With the RAP starting to show similar solutions to the NAM, have held onto the CIGS into the afternoon. Don`t have much confidence in the MOS guidance indicating IFR CIGS, but it is not out of the question. As for stronger storms, models have the best forcing moving through between 00Z and 06Z. TS coverage may end up being more scattered, but feel PROBs are good enough to include a TEMPO. There will likely need to be refinements to the forecast as the weather moves in. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...53 LONG TERM...65 AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
258 AM CDT FRI APR 24 2015 ...UPDATED LONG TERM DISCUSSION... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 342 PM CDT THU APR 23 2015 FORECAST ISSUES IN THE SHORT TERM CENTER AROUND THUNDERSTORM CHANCES TONIGHT AND FRIDAY AND THE SEVERE WEATHER POTENTIAL ASSOCIATED WITH THE STORMS. THE ATMOSPHERE OVER THE HIGH PLAINS OF EASTERN COLORADO AND FAR WESTERN KANSAS WAS BECOMING MODERATELY UNSTABLE WITH DAYTIME HEATING THIS AFTERNOON. A SURFACE TROUGH OF LOW PRESSURE STRENGTHENING OVER EASTERN COLORADO WAS ALSO PROVIDING SOME LOW LEVEL CONVERGENCE AND TRIGGERING WIDELY SCATTERED THUNDERSTORMS. SPC MESOANALYSIS SHOWS 30- 40 KNOTS OF SHEAR IN THE 0-6 KM LAYER BUT ABOVE THIS LAYER, STRONGER SHEAR WAS IN PLACE IN THE PRESENCE OF A STRONG SUBTROPICAL JET. THE STORMS OVER EASTERN COLORADO WILL BE IN A FAVORABLE ENVIRONMENT TO BECOME ROTATING SUPERCELLS. GIVEN THE STRONG EVACUATION ALOFT, LARGE HAIL WILL BE A GOOD POSSIBILITY. THE HRRR MODEL HAS BEEN VERY CONSISTENT WITH THUNDERSTORMS MOVING INTO WESTERN KANSAS AROUND JOHNSON AND SYRACUSE AND POINTS NORTH THIS EVENING AROUND 23Z-01Z AND HAVE KEPT THE BEST CHANCES IN THAT AREA EARLY THIS EVENING. AS THE NIGHT CONTINUES, AN AREA OF THUNDERSTORMS COULD CONTINUE TO DEVELOP OVER WEST CENTRAL AND NORTHWEST KANSAS AS A WEAK MID LEVEL DISTURBANCE ALONG WITH THE LEFT EXIT REGION OF AN UPPER LEVEL SPEED MAX MOVES OVER THE AREA. THE MODELS ALSO SHOW INCREASING SOUTHERLY FLOW AT THE 850 MILLIBAR LEVEL WHICH COULD ALSO HELP SUSTAIN THUNDERSTORMS THROUGH THE NIGHT. THE BEST CHANCE FOR STORMS SHOULD BE ALONG AND/OR NORTH OF HIGHWAY 50 AND 156. THE THREAT FOR SEVERE WEATHER SHOULD DIMINISH SOMEWHAT AFTER DARK BUT CAN`T RULE OUT THE POSSIBILITY OF A FEW ELEVATED HAILERS. CHANCES FOR STORMS WILL DIMINISH LATER TONIGHT AS THE MID/UPPER LEVEL SUPPORT MOVES EAST OF THE AREA. ON FRIDAY, THE MAIN UPPER TROUGH MOVES OUT INTO THE CENTRAL AND SOUTHERN PLAINS. THE MODELS DEVELOP A SURFACE LOW OVER WEST CENTRAL KANSAS WITH A FRONTAL BOUNDARY EXTENDING EAST FROM THE LOW. BY FRIDAY AFTERNOON THE LOW WILL BE PROGRESSING EAST WHILE A DRYLINE PUSHES EAST ACROSS SOUTHWEST THROUGH SOUTH CENTRAL KANSAS. THE UPPER LEVEL JET PROPAGATES EAST THROUGH THE DAY. THE 18Z MODELS ARE NOW LOOKING LESS FAVORABLE FOR SEVERE POTENTIAL AS THE BETTER 0-6 KM SHEAR WILL BE TO THE SOUTH AND EAST OF THE DODGE CITY CWFA DURING THE MID/LATE AFTERNOON HOURS. WITH SOME GOOD INSTABILITY OVER THE NORTHERN AND EASTERN SECTIONS OF THE CWA, THERE WILL STILL BE POTENTIAL FOR SOME SEVERE STORMS AS WELL AS THE POTENTIAL FOR TORNADOES ALONG AND NORTH OF THE FRONTAL BOUNDARY OVER CENTRAL KANSAS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 255 AM CDT FRI APR 24 2015 MODELS REMAIN IN GOOD AGREEMENT WITH AN UPPER LEVEL SHORT WAVE RIDGE AXIS CROSSING THE CENTRAL HIGH PLAINS EARLY THIS WEEKEND AS A SURFACE COLD FRONT DROPS SOUTH ACROSS SOUTHWEST KANSAS. DESPITE A COLD FRONT CROSSING WESTERN KANSAS DURING THE DAY THE 850MB TEMPERATURES CONTINUE TO SUGGEST TEMPERATURES RANGING FROM THE MID 70S IN WEST CENTRAL AND NORTH CENTRAL KANSAS TO THE LOWER 80S IN SOUTH CENTRAL KANSAS. THIS COLD FRONT WILL MOVE SOUTH OF THE OKLAHOMA BORDER SATURDAY NIGHT WHERE IT IS FORECAST TO BECOME NEARLY STATIONARY THROUGH THE EARLY NEXT WEEK. NORTH OF THIS BOUNDARY A MOIST UPSLOPE FLOW NEAR THE SURFACE AND ISENTROPIC LIFT WILL BEGIN TO IMPROVE ACROSS SOUTHWEST KANSAS AS A DEVELOPING UPPER LOW MOVES SLOWLY EAST ACROSS NEW MEXICO. LOW LEVEL MOISTURE, ISENTROPIC LIFT AND DIFULENT FLOW ALOFT SUNDAY THROUGH EARLY TUESDAY CONTINUES TO SUPPORT IMPROVING CHANCES FOR PRECIPITATION ACROSS SOUTHWEST KANSAS, ESPECIALLY SOUTH OF ROUGHLY A GARDEN CITY TO LARNED LINE SUNDAY NIGHT THROUGH LATE MONDAY IF THE TRACK OF THIS UPPER LOW REMAINS UNCHANGED. CLOUD COVER AND PRECIPITATION CHANCES MONDAY COULD EASILY RESULT IN HIGHS STRUGGLING TO CLIMB MUCH HIGHER THE LOW TO MID 50S NEAR THE OKLAHOMA BORDER. FROM LATE MONDAY INTO EARLY TUESDAY THE UPPER LOW IS FORECAST TO CROSS FROM THE TEXAS PANHANDLE INTO SOUTHEAST OKLAHOMA. AS THIS SYSTEM MOVES SOUTH OF THE OKLAHOMA BORDER LATE MONDAY AND EARLY TUESDAY ISENTROPIC DOWNGLIDE WILL DEVELOP ACROSS SOUTHWEST KANSAS BRINGING AN END TO THE PRECIPITATION CHANCES FROM WEST TO EAST. GUSTY NORTHEAST WINDS WILL ALSO DEVELOP AS COOLER AIR RETURNS TO WESTERN KANSAS. A SURFACE RIDGE AXIS WILL THEN CROSS WESTERN KANSAS MID WEEK WHICH WILL KEEP TEMPERATURES NEAR OR BELOW THE SEASONAL NORMALS FOR THIS TIME OF YEAR. A WARMING TREND WILL THEN BEGIN LATE WEEK AS THE SURFACE HIGH MOVES EAST INTO THE MISSISSIPPI VALLEY AND A SURFACE TROUGH OF LOW PRESSURE DEVELOPS ALONG THE LEE OF THE ROCKIES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 110 AM CDT FRI APR 24 2015 IFR/LIFR STRATUS WILL IMPACT AREA TERMINALS EARLY FRIDAY MORNING, WITH POTENTIAL FOR REDUCED VISIBILITY IN BR, AS SURFACE MOISTURE TRANSPORT IS MAXIMIZED AHEAD OF A DEEPENING SURFACE LEE LOW. SCATTERED CONVECTION BECOMES AN IMPACT IN THE EARLY TO MID AFTERNOON. A BRIEF PERIOD OF SEVERE STORMS THE LARGE HAIL (2 TO 3 INCH DIAMETER) AND DAMAGING WIND WILL BE POSSIBLE WITH ANY ROTATING UPDRAFTS MAINLY AFFECTING THE HAYS AND DODGE CITY TERMINALS AHEAD OF THE SURFACE DRYLINE IN THE MORE MOIST ENVIRONMENT. && .PRELIMINARY POINT TEMPS/POPS... DDC 81 49 78 47 / 20 20 10 10 GCK 77 48 77 47 / 20 20 10 20 EHA 76 47 79 48 / 10 10 10 10 LBL 80 48 81 49 / 10 10 10 10 HYS 73 50 73 45 / 40 40 10 20 P28 82 52 80 50 / 20 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GERARD LONG TERM...BURGERT AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
111 AM CDT FRI APR 24 2015 ...UPDATED AVIATION SECTION... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 342 PM CDT THU APR 23 2015 FORECAST ISSUES IN THE SHORT TERM CENTER AROUND THUNDERSTORM CHANCES TONIGHT AND FRIDAY AND THE SEVERE WEATHER POTENTIAL ASSOCIATED WITH THE STORMS. THE ATMOSPHERE OVER THE HIGH PLAINS OF EASTERN COLORADO AND FAR WESTERN KANSAS WAS BECOMING MODERATELY UNSTABLE WITH DAYTIME HEATING THIS AFTERNOON. A SURFACE TROUGH OF LOW PRESSURE STRENGTHENING OVER EASTERN COLORADO WAS ALSO PROVIDING SOME LOW LEVEL CONVERGENCE AND TRIGGERING WIDELY SCATTERED THUNDERSTORMS. SPC MESOANALYSIS SHOWS 30- 40 KNOTS OF SHEAR IN THE 0-6 KM LAYER BUT ABOVE THIS LAYER, STRONGER SHEAR WAS IN PLACE IN THE PRESENCE OF A STRONG SUBTROPICAL JET. THE STORMS OVER EASTERN COLORADO WILL BE IN A FAVORABLE ENVIRONMENT TO BECOME ROTATING SUPERCELLS. GIVEN THE STRONG EVACUATION ALOFT, LARGE HAIL WILL BE A GOOD POSSIBILITY. THE HRRR MODEL HAS BEEN VERY CONSISTENT WITH THUNDERSTORMS MOVING INTO WESTERN KANSAS AROUND JOHNSON AND SYRACUSE AND POINTS NORTH THIS EVENING AROUND 23Z-01Z AND HAVE KEPT THE BEST CHANCES IN THAT AREA EARLY THIS EVENING. AS THE NIGHT CONTINUES, AN AREA OF THUNDERSTORMS COULD CONTINUE TO DEVELOP OVER WEST CENTRAL AND NORTHWEST KANSAS AS A WEAK MID LEVEL DISTURBANCE ALONG WITH THE LEFT EXIT REGION OF AN UPPER LEVEL SPEED MAX MOVES OVER THE AREA. THE MODELS ALSO SHOW INCREASING SOUTHERLY FLOW AT THE 850 MILLIBAR LEVEL WHICH COULD ALSO HELP SUSTAIN THUNDERSTORMS THROUGH THE NIGHT. THE BEST CHANCE FOR STORMS SHOULD BE ALONG AND/OR NORTH OF HIGHWAY 50 AND 156. THE THREAT FOR SEVERE WEATHER SHOULD DIMINISH SOMEWHAT AFTER DARK BUT CAN`T RULE OUT THE POSSIBILITY OF A FEW ELEVATED HAILERS. CHANCES FOR STORMS WILL DIMINISH LATER TONIGHT AS THE MID/UPPER LEVEL SUPPORT MOVES EAST OF THE AREA. ON FRIDAY, THE MAIN UPPER TROUGH MOVES OUT INTO THE CENTRAL AND SOUTHERN PLAINS. THE MODELS DEVELOP A SURFACE LOW OVER WEST CENTRAL KANSAS WITH A FRONTAL BOUNDARY EXTENDING EAST FROM THE LOW. BY FRIDAY AFTERNOON THE LOW WILL BE PROGRESSING EAST WHILE A DRYLINE PUSHES EAST ACROSS SOUTHWEST THROUGH SOUTH CENTRAL KANSAS. THE UPPER LEVEL JET PROPAGATES EAST THROUGH THE DAY. THE 18Z MODELS ARE NOW LOOKING LESS FAVORABLE FOR SEVERE POTENTIAL AS THE BETTER 0-6 KM SHEAR WILL BE TO THE SOUTH AND EAST OF THE DODGE CITY CWFA DURING THE MID/LATE AFTERNOON HOURS. WITH SOME GOOD INSTABILITY OVER THE NORTHERN AND EASTERN SECTIONS OF THE CWA, THERE WILL STILL BE POTENTIAL FOR SOME SEVERE STORMS AS WELL AS THE POTENTIAL FOR TORNADOES ALONG AND NORTH OF THE FRONTAL BOUNDARY OVER CENTRAL KANSAS. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 315 PM CDT THU APR 23 2015 THE WEAK UPPER LEVEL LOW WILL CONTINUE TO MOVE EASTWARD ACROSS THE KS/NE BORDER FRIDAY NIGHT. THIS WILL HELP PUSH A SURFACE LOW AND ASSOCIATED COLD FRONT THROUGH THE REMAINDER OF THE CWA AND INTO EASTERN KANSAS. A FEW LINGERING THUNDERSTORMS WILL BE POSSIBLE ACROSS CENTRAL KANSAS AS WELL AS AROUND THE I-70 CORRIDOR IN THE EVENING WITH PRECIPITATION CHANCES COMING TO AN END SOMETIME AFTER MIDNIGHT. NORTHWESTERLY WINDS WILL BE FELT BEHIND THIS SYSTEM AND CONTINUE THROUGH THE MOST OF SATURDAY. SKIES LOOK TO BECOME MOSTLY CLEAR BY SUNRISE SATURDAY AND CONTINUE THROUGH THE DAY SATURDAY AS DRIER AIR MOVES INTO THE AREA. WINDS THEN SHIFT TO MORE OF AN EASTERLY DIRECTION SATURDAY EVENING THROUGH SUNDAY AS AN AREA OF LOW PRESSURE DEVELOPS AND INTENSIFIES SOUTHWEST OF THE AREA. THIS OCCURS IN RESPONSE TO AN UPPER LEVEL OPEN WAVE DIGGING INTO THE DESERT SOUTHWEST SATURDAY, INTENSIFYING INTO AN UPPER LEVEL LOW OVER THE FOUR CORNER`S REGION SUNDAY. MODELS THEN SUGGEST THAT THIS LOW WILL MOVE EASTWARD ACROSS THE SOUTHERN PLAINS MONDAY INTO TUESDAY. HOWEVER, WITH THIS SYSTEM BEING MORE THAN 4 DAYS OUT TIMING AND POSITION WILL MOST LIKELY CHANGE OVER THE NEXT COUPLE OF MODEL RUNS. IF FUTURE MODEL RUNS PREDICT THIS FEATURE TO MOVE FARTHER NORTH, THE CWA COULD SEE SOME BENEFICIAL RAIN SUNDAY NIGHT THROUGH TUESDAY. NEVERTHELESS, HIGH CLOUDS LOOK INCREASE IN COVERAGE SUNDAY AS THIS FEATURE MOVES CLOSER TO THE AREA WITH MOSTLY CLOUDY SKIES EXPECTED SUNDAY NIGHT THROUGH AT LEAST MONDAY. WINDS SHIFT TO MORE OF A NORTHERLY DIRECTION BEHIND THIS SYSTEM THROUGH TUESDAY. UPPER LEVEL RIDGING IS THEN EXPECTED TO BUILD INTO THE WESTERN UNITED STATES BEHIND THIS SYSTEM WITH HIGH PRESSURE BEING THE DOMINATING FACTOR AT THE SURFACE. THIS WILL BRING DRIER CONDITIONS TO WESTERN KANSAS FOR THE REMAINDER OF THE WEEK. AS FOR TEMPERATURES, LOWS FRIDAY NIGHT THROUGH MONDAY NIGHT WILL GENERALLY BE IN THE 40S WITH THE EXCEPTION OF SOUTH CENTRAL KANSAS FRIDAY NIGHT WHERE LOWER 50S WILL BE POSSIBLE AND WEST CENTRAL KANSAS MONDAY NIGHT WHERE UPPER 30S COULD BE POSSIBLE. HIGHS LOOK TO BE IN THE 70S WITH A FEW AREAS ACROSS THE KS/OK BORDER REACHING INTO THE LOWER 80S SATURDAY THEN DECREASE INTO THE 60S SUNDAY. THE COLDEST DAY OVER THE EXTENDED PERIOD LOOKS TO BE ON MONDAY WITH HIGHS POSSIBLY ONLY REACHING TO AROUND 60 DEGREES. HIGHS ARE FORECASTED TO REACH INTO THE MID 60S TUESDAY WITH 70S POSSIBLE WEDNESDAY. LOWS TUESDAY THROUGH THURSDAY MORNING LOOK TO DIP INTO THE 40S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 110 AM CDT FRI APR 24 2015 IFR/LIFR STRATUS WILL IMPACT AREA TERMINALS EARLY FRIDAY MORNING, WITH POTENTIAL FOR REDUCED VISIBILITY IN BR, AS SURFACE MOISTURE TRANSPORT IS MAXIMIZED AHEAD OF A DEEPENING SURFACE LEE LOW. SCATTERED CONVECTION BECOMES AN IMPACT IN THE EARLY TO MID AFTERNOON. A BRIEF PERIOD OF SEVERE STORMS THE LARGE HAIL (2 TO 3 INCH DIAMETER) AND DAMAGING WIND WILL BE POSSIBLE WITH ANY ROTATING UPDRAFTS MAINLY AFFECTING THE HAYS AND DODGE CITY TERMINALS AHEAD OF THE SURFACE DRYLINE IN THE MORE MOIST ENVIRONMENT. && .PRELIMINARY POINT TEMPS/POPS... DDC 81 49 78 47 / 20 20 10 10 GCK 77 48 77 47 / 20 20 10 20 EHA 76 47 79 48 / 10 10 10 10 LBL 80 48 81 49 / 10 10 10 10 HYS 73 50 73 45 / 40 40 10 20 P28 82 52 80 50 / 20 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GERARD LONG TERM...HOVORKA_42 AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1142 PM CDT Thu Apr 23 2015 ...AVIATION UPDATE... .SHORT TERM...(This Evening through Friday) Issued at 329 PM CDT THU APR 23 2015 A mid-level ridge was in place over the Central and Southern Plains today with a mid-level trough progressing eastward across the northeastern U.S. and another trough noted just north of the Baja Peninsula. At the surface, southeasterly winds prevailed as high pressure remained stationed just east of the forecast area. This southeasterly flow helped to keep a low/mid cloud deck in place across much of the region today, limiting the daytime heating. However, visible satellite imagery showed more breaks in the cloud cover near the Kansas/Nebraska border, resulting in afternoon temperatures reaching into the middle 60s. Further south in locations with more persistent cloud cover afternoon temperatures struggled to reach near 60 degrees. The mid-level trough north of the Baja Peninsula will lift northeastward toward the Four Corners region overnight and progress north of the Texas/Oklahoma panhandles Friday afternoon, which will help to provide ample mid-level support for thunderstorm activity late Friday afternoon through Friday evening. Ahead of this advancing trough, water vapor imagery this afternoon showed a few weak embedded shortwaves developing along the lee-side of the trough over Wyoming and Colorado with increased cloud cover noted over that region. Models show these weak waves shifting eastward with the eastward progression of the trough, moving into Nebraska and northern Kansas overnight into Friday morning. In general, short-range models have trended a bit weaker with the shower and thunderstorm potential for late tonight through the morning hours as the region should remain capped and forcing is limited. However, with MUCAPE values upwards of 500-1000 J/kg and 45-55kts of 0-6km shear, cannot rule out the potential for a few strong elevated thunderstorms to develop in which some small hail will be possible. Short-range models show that the precipitation should be pretty isolated this evening and become more widely scattered through the overnight hours before diminishing in coverage from west to east during the mid to late morning hours. As a result, models suggest that we could see a window of a few hours from mid/late morning through early/mid afternoon in which locations are precipitation-free and, according to some model soundings, may potentially see some breaks in the cloud cover, especially closer toward central Kansas. This diminish in cloud cover will allow for more daytime heating in the afternoon hours to boost temperatures into the low/mid 70s from central to east central Kansas, with cooler temperatures in the mid/upper 60s across northeast Kansas from the lingering cloud cover. However, these high temperatures will be very dependent upon how quickly the morning precipitation dissipates and whether or not we are able to diminish the cloud cover enough during the early/mid afternoon hours, so we will need to continue to closely monitor these short-term conditions. .LONG TERM...(Friday Night through Thursday) Issued at 329 PM CDT THU APR 23 2015 Friday afternoon into the overnight presents a complicated weather scenario with a likelihood of severe weather in the area, and a potential for a few significant severe events. The primary forecast questions through this period will be 1) How far north does the warm sector surge? 2) How broad east/west will the unstable warm sector be? 3) How much and how soon will the boundary layer stabilize by mid to late evening? In terms of the questions above, various model guidance are generally in the same ballpark regarding how far north the warm sector will surge, but the northern edge of the surface based instability ranges from somewhere near the Nebraska border (GFS) to a Council Grove to Lawrence line (NAM/NMM). The rest of guidance is in between, and frankly the ECMWF rendition of the surface low and warm front track looks to be quite reasonable, with the warm sector coming as far north as Minneapolis to Manhattan to Holton line. Most indications are also that the warm sector will not be particularly broad east/west, and this *may* be able to limit the potential for long track severe storms a bit as the individual storm forward speed (40+ mph) should be faster than the system as a whole, and they could move toward less unstable air with time. In terms of evening stabilization, all indications point to an unstable warm sector airmass through approximately 8-11 PM before becoming increasingly stable. This is not entirely for sure as the surface low will track directly across the area after midnight, but it does seem likely that CINH will increase and the tornado threat decrease by late evening. The relative certainties in this forecast are following 1) Thunderstorms will develop and move across the forecast area. 2) Wind shear parameters are very impressive and will support storm organization. 3) The combination of steep lapse rates and strong shear will support large hail (some very large) in storms both north and south of the front. The rest of the details are fuzzier but important. Damaging wind potential does not appear to be a huge threat given low LCL heights, but the potential for some upscale growth by mid/late evening and very strong ambient wind fields suggest that a wind threat could develop. The potential for tornadoes is conditional, but very present. A worst case scenario would be if cells can remain semi-discrete or move east of the main cluster of convection as any isolated supercell in the warm sector would have full access to 30+ KTS of 0-1 km wind shear underneath a strong mid level steering flow (60 KTS at 500 hPa) and exhaust jet aloft (130 KTS at 250 hPa). There would seem to be a primary window of opportunity between 6 PM and 10 PM for tornado potential, especially with any isolated supercells, as the low level jet rapidly intensifies during this period but inhibition is slow to increase. The take away message is that the potential exists for all modes of severe weather, and while there are complicating factors, it will be important to prepare for a few significant severe storms. Precipitation looks to exit the area by sunrise on Saturday. A cold front will then move into the area from the north on Saturday afternoon. There will be some weak instability across the area, but most indications point to a slightly capped boundary layer with weak forcing along the front so currently have a dry afternoon forecast. However, if low level moisture is a bit deeper or if temperatures ahead of the front warm up more than forecast, could possibly see a storm or two develop. The remainder of the forecast is rather uneventful. Have maintained a slight chance for showers early next week as a slow moving closed upper low drifts across the southern Plains, but for the most part it looks like precip should remain south of the forecast area. Temperatures look to be near or slightly below normal for much of the long term period. && .AVIATION...(For the 06Z TAFs through 06Z Friday Night) Issued at 1142 PM CDT THU APR 23 2015 Forecast seems to be on track, so there are not a lot of changes to the prev forecast. Still looks like there is a chance for elevated showers and thunderstorms with it being tough to pin point timing and location. Therefore continue with VCTS. There is a little more uncertainty in how long MVFR CIGS hang in through the day Friday. With the RAP starting to show similar solutions to the NAM, have held onto the CIGS into the afternoon. Don`t have much confidence in the MOS guidance indicating IFR CIGS, but it is not out of the question. As for stronger storms, models have the best forcing moving through between 00Z and 06Z. TS coverage may end up being more scattered, but feel PROBs are good enough to include a TEMPO. There will likely need to be refinements to the forecast as the weather moves in. && .TOP WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...Hennecke LONG TERM...Barjenbruch AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1015 PM MDT THU APR 23 2015 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 112 PM MDT THU APR 23 2015 LOW CLOUDS THAT WERE PRESENT ACROSS THE AREA DURING THE MORNING HOURS CONTINUED TO LINGER FOR SOME LOCATIONS ACROSS THE TRI STATE AREA IN THE EARLY AFTERNOON ON VISIBLE SATELLITE IMAGERY...HOWEVER MOST LOCATIONS WERE UNDER PARTLY TO MOSTLY CLEAR SKIES. RAP 500 MB ANALYSIS AND WATER VAPOR IMAGERY SHOWED A SHORTWAVE TROUGH ACROSS THE CENTRAL HIGH PLAINS REGION...HOWEVER A LONGWAVE TROUGH ACROSS THE GREAT BASIN REGION WAS MOVING EASTWARD INTO THE CENTRAL HIGH PLAINS. THE ADVANCING TROUGH WILL BRING SOME POCKETS OF HIGHER POTENTIAL VORTICITY VALUES ACROSS THE TRI STATE AREA LATER THIS AFTERNOON AND TONIGHT...WHICH WILL HELP DESTABILIZE THE ATMOSPHERE AND CAUSE STORMS TO DEVELOP. A SURFACE STATIONARY BOUNDARY TO THE WEST ALONG THE COLORADO FRONT RANGE WILL ALSO PROVIDE THE NEEDED PUSH AT THE SURFACE TO GET STORMS GOING. MOST MODEL GUIDANCE HAS INITIATION OCCURRING SOMETIME BETWEEN 21 AND 00Z IN EASTERN COLORADO WITH STORMS GETTING GOING BY 00Z. PROFILE CAPE BETWEEN 1000 AND 1500 J/KG AND BULK SHEAR BETWEEN 30 AND 35 KTS MAY BE ENOUGH TO CAUSE SOME STORMS TO PRODUCE LARGE HAIL...AND DRY MID LEVELS IN MODEL SOUNDINGS WITH DCAPE BETWEEN 800 AND 1000 J/KG COULD RESULT IN DAMAGING WINDS GUSTS. THE SHEAR VALUES DIMINISH OVERNIGHT...BUT CAPE WILL STILL BE PRESENT OVERNIGHT AS STORMS MOVE EASTWARD. THEREFORE...EXPECTING STORMS TO CONTINUE OVERNIGHT FOR SOME LOCATIONS. THE SURFACE STATIONARY FRONTAL BOUNDARY WILL REMAIN DRAPED ACROSS THE TRI STATE AREA OVERNIGHT...WHICH WILL BRING SOUTHEAST WINDS AT THE SURFACE AND INCREASED RELATIVE HUMIDITIES OVERNIGHT. AS A RESULT...FOG WILL DEVELOP AND CLOUD COVER WILL REMAIN INCREASED OVERNIGHT. EXPECTING LOW TEMPERATURES TO BE SLIGHTLY WARMER AS A RESULT OF THE BLANKETING CLOUD COVER IN THE UPPER 40S. FOG AND LOWER CLOUDS WILL BEGIN TO DIMINISH TOWARD THE EARLY TO MID MORNING HOURS...BUT CLOUDS WILL RETURN DURING THE EARLY AFTERNOON AS A SURFACE WARM FRONT APPROACHES THE TRI STATE AREA. RAIN SHOWERS AND THUNDERSTORMS WILL DEVELOP IN THE LATE MORNING TO EARLY AFTERNOON HOURS...MAINLY EAST OF HIGHWAY 83. CAPE VALUES AROUND 1000 J/KG AND BULK SHEAR BETWEEN 35 AND 40 KTS WILL BRING SOME SEVERE POTENTIAL WITH LARGE HAIL AND DAMAGING WINDS...ALTHOUGH THE MAIN ATMOSPHERIC DYNAMICS ARE WELL EAST OF OUR FORECAST AREA. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 241 PM MDT THU APR 23 2015 THE UPPER TROUGH AND SURFACE LOW MOVING ACROSS THE AREA ON FRIDAY WILL CONTINUE TO LIFT ENE AS A CLOSED LOW FRIDAY NIGHT WITH WEAK SHORT WAVE RIDGING ALOFT OVER THE CENTRAL HIGH PLAINS ON SATURDAY. SATURDAY LOOKS MOSTLY DRY BETWEEN SYSTEMS WITH THE NEXT LOW PRESSURE CENTER DIVING INTO THE SOUTHWEST U.S. SOUTH OF THE 4-CORNERS REGION DURING BY SUNDAY MORNING. THE LOW ALOFT MOVES INTO THE WEST TEXAS PANHANDLE REGION BY MONDAY MORNING...MOVING SLOWLY INTO POSITION OVER EAST TEXAS AND EAST OKLAHOMA BY TUESDAY MORNING AS THE SURFACE LOW TRACKS FURTHER SOUTH ALONG THE GULF COAST OF TEXAS. WITH THE MAIN LOW PRESSURE AREA ACROSS THE SOUTH CENTRAL U.S. WELL SOUTH OF THE FORECAST AREA...THE SATURDAY NIGHT THROUGH MONDAY NIGHT TIME FRAME WILL REMAIN UNSETTLED ACROSS THE FORECAST AREA WITH A CHANCE OF RAIN SHOWERS AND THUNDERSTORMS...BUT EXPECT THE BULK OF THE PRECIPITATION TO STAY OVER THE SOUTHERN PLAINS. TUESDAY THROUGH THURSDAY SHOULD BE DRY AS THE AMPLIFYING RIDGE OVER THE WEST COAST MOVES OVER THE ROCKIES AND HIGH PLAINS REGION. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1015 PM MDT THU APR 23 2015 KGLD...STRATUS AND MVFR CIGS EXPECTED AT TAF ISSUANCE OR VERY SHORTLY AFTER WITH CONFIDENCE INCREASING IN THE 07Z-15Z TIMEFRAME FOR WIDESPREAD IFR/VLIFR CONDITIONS TO OCCUR. CONDITIONS EXPECTED TO IMPROVE TO VFR CATEGORY AROUND 18Z-19Z. A WEATHER DISTURBANCE APPROACHES THE TERMINAL AROUND 21Z MOVING THROUGH AND OUT OF THE IMMEDIATE AREA AROUND 00Z WITH ONLY SOME MID AND HIGH CLOUDS LEFTOVER. HAVE MENTIONED VCTS IN THE 21Z-00Z TIMEFRAME BUT SOME OF THE MODELS SUGGESTING A LITTLE LATER STARTING AND ENDING TIME SO ADJUSTMENTS WILL LIKELY OCCUR. WINDS THROUGH THE PERIOD GENERALLY 12KTS OR LESS...EXCEPT IN THE VICINITY OF ANY THUNDERSTORMS. KMCK...MVFR CIGS EXPECTED AT TAF ISSUANCE OR VERY SHORTLY AFTER WITH CONFIDENCE INCREASING IN THE 08Z-15Z TIMEFRAME FOR WIDESPREAD IFR/VLIFR CONDITIONS TO OCCUR. FOR 16Z-19Z MVFR CONDITIONS EXPECTED THEN VFR BY 20Z. A WEATHER DISTURBANCE APPROACHES THE TERMINAL AROUND 22Z MOVING THROUGH AND OUT OF THE IMMEDIATE AREA AROUND 01Z WITH ONLY SOME MID CLOUDS LEFTOVER. HAVE MENTIONED VCTS IN THE 22Z-01Z TIMEFRAME BUT SOME OF THE MODELS SUGGESTING A LITTLE LATER STARTING AND ENDING TIME SO ADJUSTMENTS WILL LIKELY OCCUR. WINDS THROUGH THE PERIOD GENERALLY UNDER 12KTS...EXCEPT IN THE VICINITY OF ANY THUNDERSTORMS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...MK LONG TERM...LOCKHART AVIATION...99
AREA FORECAST DISCUSSION
NWS PADUCAH KY
627 AM CDT FRI APR 24 2015 .UPDATE... ISSUED AT 625 AM CDT FRI APR 24 2015 THE AVIATION SECTION HAS BEEN UPDATED FOR THE 12Z TAF ISSUANCE. .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 255 AM CDT FRI APR 24 2015 SEVERAL CHALLENGES TO THE FORECAST FOR THIS PART OF THE PACKAGE. MID-HIGH LEVEL CLOUDS STREAMING ACROSS THE AREA EARLY THIS MORNING AND SATELLITE SUGGESTS PATCHY MID-HIGH LEVEL CLOUDS WILL CONTINUE THROUGH MOST OF THE DAY. SEVERAL SMALL PIECES OF ENERGY HEADED OUR WAY TODAY. HRRR MODEL PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS OVER THE WESTERN SECTIONS LATER THIS MORNING AND THESE ARE SLOWLY EXPECTED TO SPREAD EAST LATE THIS AFTERNOON. BY TONIGHT A WARM FRONT WILL DEVELOP TO OUR SOUTH. CURRENT WATER VAPOR IMAGES DEPICT MOISTURE STREAMING NORTHEAST OUT OF OLD MEXICO AND TEXAS. SHOWERS AND THUNDERSTORMS SHOULD BECOME MORE WIDESPREAD TONIGHT ACROSS THE AREA. ON SATURDAY...THERE SHOULD BE A LULL IN THE ACTION DURING THE MORNING HOURS AS THE MAIN PRECIP ENDS FROM SOUTHWEST TO NORTHEAST. THE CLOUDS ARE EXPECTED TO BREAK UP FOR SEVERAL HOURS DURING THE MORNING HOURS ESPECIALLY OVER THE CENTRAL AND SOUTHERN SECTIONS. AS THIS HAPPENS, MOST OF THE AREA WILL BECOME VERY UNSTABLE AS WIND FIELDS BECOME MORE FAVORABLE FOR SEVERE WEATHER DURING THE AFTERNOON HOURS. SPC HAS A MAJORITY OF THE AREA IN AN ENHANCED RISK AND THIS SEEMS PRUDENT AS CONFIDENCE LEVELS CONTINUE TO INCREASE FOR SEVERE WEATHER. VERY FAVORABLE LAPSE RATES SHOULD ALLOW DEEP CONVECTION TO BEGIN BY EARLY-MID AFTERNOON. 0-3 KM BULK SHEAR VECTORS WILL RANGE FROM 35 TO 40 KTS AS LOW LEVEL WINDS INCREASE...ESPECIALLY OVER WEST KENTUCKY. THERE IS POTENTIAL FOR LARGE HAIL...DAMAGING WINDS...AND A FEW TORNADOES TOMORROW AFTERNOON AND EARLY EVENING ESPECIALLY OVER WESTERN KENTUCKY. PRECIPITATION SHOULD END SATURDAY NIGHT WITH SOME SUNSHINE ON SUNDAY. .LONG TERM...(MONDAY THROUGH THURSDAY) ISSUED AT 255 AM CDT FRI APR 24 2015 SLIGHTLY BETTER FORECAST CONFIDENCE IN THE LONG TERM. VIRTUALLY ALL OF THE WEATHER...OR LACK THEREOF...IN THE LONG TERM PERIOD HINGES ON THE DEVELOPMENT AND EVOLUTION OF A STORM SYSTEM FORECAST TO MOVE OUT OF THE SOUTHERN PLAINS. THE GFS CONTINUES TO TRACK THIS SYSTEM EAST NORTHEASTWARD BRINGING IT AND ITS ASSOCIATED PRECIPITATION SLIGHTLY FARTHER NORTH THEREBY AFFECTING THE SOUTHERN HALF OF OUR CWA TUESDAY AND TUESDAY NIGHT. IN THE SAME TIME FRAME THE ECMWF AND CANADIAN CONTINUE TO TRACK THE SYSTEM MORE EASTERLY KEEPING ALL PRECIPITATION SOUTH OF OUR CWA. ON A SIDE NOTE...THE LATEST GFS SOLUTION IS SLIGHTLY FARTHER SOUTH THAN IT WAS FORECASTING 24 HOURS AGO. IF THIS TREND CONTINUES WE MAY BE ABLE TO EVENTUALLY REMOVE CURRENT POPS. FOR WHATEVER REASON THE SUPERBLEND STILL LEANS MORE TOWARD THE GFS SOLUTION SO BASICALLY TOOK THE SUPERBLEND POPS AND TONED THEM DOWN A BIT. HIGH PRESSURE AT THE SURFACE SHOULD KEEP THE REGION DRY WITH THE EXCEPTION OF TUESDAY AND TUESDAY NIGHT. TEMPERATURES THROUGH MOST OF THE PERIOD WILL REMAIN BELOW NORMAL BUT RIDGING ALOFT SHOULD WARM READINGS BACK TO NEAR NORMAL BY THE END OF THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 615 AM CDT FRI APR 24 2015 VFR CONDITIONS EXPECTED THROUGH 06Z ALTHOUGH ISOLATED SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA FROM LATE THIS MORNING INTO THE EVENING HOURS. EXPECT THE COVERAGE TO INCREASE WITH A BETTER CHANCE OF OCCURRANCE OVER A TAF SITE AFTER 06Z. MFVR AND POSSIBLY IFR CONDITIONS WITH SHOWERS AND THUNDERSTORMS. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...PS LONG TERM...JP AVIATION...PS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
300 AM CDT FRI APR 24 2015 .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 255 AM CDT FRI APR 24 2015 SEVERAL CHALLENGES TO THE FORECAST FOR THIS PART OF THE PACKAGE. MID-HIGH LEVEL CLOUDS STREAMING ACROSS THE AREA EARLY THIS MORNING AND SATELLITE SUGGESTS PATCHY MID-HIGH LEVEL CLOUDS WILL CONTINUE THROUGH MOST OF THE DAY. SEVERAL SMALL PIECES OF ENERGY HEADED OUR WAY TODAY. HRRR MODEL PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS OVER THE WESTERN SECTIONS LATER THIS MORNING AND THESE ARE SLOWLY EXPECTED TO SPREAD EAST LATE THIS AFTERNOON. BY TONIGHT A WARM FRONT WILL DEVELOP TO OUR SOUTH. CURRENT WATER VAPOR IMAGES DEPICT MOISTURE STREAMING NORTHEAST OUT OF OLD MEXICO AND TEXAS. SHOWERS AND THUNDERSTORMS SHOULD BECOME MORE WIDESPREAD TONIGHT ACROSS THE AREA. ON SATURDAY...THERE SHOULD BE A LULL IN THE ACTION DURING THE MORNING HOURS AS THE MAIN PRECIP ENDS FROM SOUTHWEST TO NORTHEAST. THE CLOUDS ARE EXPECTED TO BREAK UP FOR SEVERAL HOURS DURING THE MORNING HOURS ESPECIALLY OVER THE CENTRAL AND SOUTHERN SECTIONS. AS THIS HAPPENS, MOST OF THE AREA WILL BECOME VERY UNSTABLE AS WIND FIELDS BECOME MORE FAVORABLE FOR SEVERE WEATHER DURING THE AFTERNOON HOURS. SPC HAS A MAJORITY OF THE AREA IN AN ENHANCED RISK AND THIS SEEMS PRUDENT AS CONFIDENCE LEVELS CONTINUE TO INCREASE FOR SEVERE WEATHER. VERY FAVORABLE LAPSE RATES SHOULD ALLOW DEEP CONVECTION TO BEGIN BY EARLY-MID AFTERNOON. 0-3 KM BULK SHEAR VECTORS WILL RANGE FROM 35 TO 40 KTS AS LOW LEVEL WINDS INCREASE...ESPECIALLY OVER WEST KENTUCKY. THERE IS POTENTIAL FOR LARGE HAIL...DAMAGING WINDS...AND A FEW TORNADOES TOMORROW AFTERNOON AND EARLY EVENING ESPECIALLY OVER WESTERN KENTUCKY. PRECIPITATION SHOULD END SATURDAY NIGHT WITH SOME SUNSHINE ON SUNDAY. .LONG TERM...(MONDAY THROUGH THURSDAY) ISSUED AT 255 AM CDT FRI APR 24 2015 SLIGHTLY BETTER FORECAST CONFIDENCE IN THE LONG TERM. VIRTUALLY ALL OF THE WEATHER...OR LACK THEREOF...IN THE LONG TERM PERIOD HINGES ON THE DEVELOPMENT AND EVOLUTION OF A STORM SYSTEM FORECAST TO MOVE OUT OF THE SOUTHERN PLAINS. THE GFS CONTINUES TO TRACK THIS SYSTEM EAST NORTHEASTWARD BRINGING IT AND ITS ASSOCIATED PRECIPITATION SLIGHTLY FARTHER NORTH THEREBY AFFECTING THE SOUTHERN HALF OF OUR CWA TUESDAY AND TUESDAY NIGHT. IN THE SAME TIME FRAME THE ECMWF AND CANADIAN CONTINUE TO TRACK THE SYSTEM MORE EASTERLY KEEPING ALL PRECIPITATION SOUTH OF OUR CWA. ON A SIDE NOTE...THE LATEST GFS SOLUTION IS SLIGHTLY FARTHER SOUTH THAN IT WAS FORECASTING 24 HOURS AGO. IF THIS TREND CONTINUES WE MAY BE ABLE TO EVENTUALLY REMOVE CURRENT POPS. FOR WHATEVER REASON THE SUPERBLEND STILL LEANS MORE TOWARD THE GFS SOLUTION SO BASICALLY TOOK THE SUPERBLEND POPS AND TONED THEM DOWN A BIT. HIGH PRESSURE AT THE SURFACE SHOULD KEEP THE REGION DRY WITH THE EXCEPTION OF TUESDAY AND TUESDAY NIGHT. TEMPERATURES THROUGH MOST OF THE PERIOD WILL REMAIN BELOW NORMAL BUT RIDGING ALOFT SHOULD WARM READINGS BACK TO NEAR NORMAL BY THE END OF THE PERIOD. && .AVIATION... ISSUED AT 1139 PM CDT THU APR 23 2015 MID-LEVEL MOISTURE WILL OVERSPREAD THE AREA THROUGH THE MORNING...AND CEILINGS MAY DESCEND TO NEAR MVFR LEVELS IN THE EVENING. A FEW SHOWERS WILL BE POSSIBLE IN THE EVENING...BUT THEY SHOULD HAVE LITTLE IMPACT ON THE TERMINALS. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...PS LONG TERM...JP AVIATION...DRS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
507 PM CDT FRI APR 24 2015 .UPDATE... JUST SENT OUT A QUICK UPDATE TO INCLUDE TORNADO WATCH 103 THROUGH 10 PM TONIGHT. STORMS TO DEVELOP ALONG AND SOUTH OF A BAROCLINIC ZONE ORIENTED EAST TO WEST MAINLY ACROSS THE INTERSTATE 20 CORRIDOR. DAMAGING WINDS...HEAVY RAIN...HAIL...AND ISOLATED TORNADOES POSSIBLE. /05/ .PREV DISCUSSION... /ISSUED 326 PM CDT FRI APR 24 2015/ DISCUSSION... LATEST SFC ANALYSIS SHOWING A DEEPENING SFC LOW ACROSS SE CO INTO SW KS WITH A DRYLINE ACROSS THE TX/OK PNDL INTO W TX. A SOUTHEAST FLANKING WARM FRONT EXTENDED FROM THE SFC LOW AND SNAKED SOUTH AND EAST INTO CENTRAL OK TO JUST SOUTH OF DFW TO NEAR TYR TO ESF. THIS WARM FRONT HAS MOVED VERY LITTLE TODAY ACROSS S/CENTRAL LA BUT HAS SHOWN A GREATER TENDENCY TO MOVE NORTHWARD INTO NORTH CENTRAL TEXAS OVER THE LAST COUPLE HOURS. CLOUD COVER REMAINS VERY THICK AND ITS THIS CLOUD COVER THAT HAS TEMPERED DAYTIME HIGH TEMPS TODAY. ITS ALSO THIS CLOUD COVER THAT HAS NOT ALLOWED FOR MUCH IN THE WAY OF INSTABILITY. LATEST MESOANALYSIS ONLY SHOWING CAPE VALUES NEAR 1000J/KG ALONG AND SOUTHWEST OF THE SLOWLY RETURNING NORTHWARD WARM FRONT. SUPERCELL THUNDERSTORM THAT FORMED SOUTH OF OUR AREA EARLIER TODAY FORMED ALONG THE WARM FRONT AND THE BEST UPPER LEVEL SUPPORT WHICH IS MEAGER AT BEST...EXISTS OUT WEST WHERE TORNADO WATCH #100 WAS JUST ISSUED FOR PORTIONS OF CENTRAL AND N TX. THE LATEST WRF OUTPUT HAS SHOWN A TENDENCY TO LIFT THE WARM FRONT TOO FAR NORTH AND THUS ITS SOLUTION WAS DISCOUNTED. HAVE INSTEAD GONE WITH A MODEL BLEND OF THE HRRR FOR THE VERY SHORT TERM...FOLLOWED BY A GFS/ECMWF BLEND BEYOND TONIGHT. HAVING SAID THAT...THE LATEST HRRR SHOWS CONVECTION DEVELOPING RAPIDLY NEAR AND NORTH OF THE I-20 CORRIDOR OF N TX LATER THIS EVENING WITH SOME OF THESE STORMS LIKELY EXHIBITING DISCRETE CHARACTERISTICS AS THEY MOVE EASTWARD INTO OUR NW ZONES. SOME OF THIS STRONG/SEVERE CONVECTION COULD EVENTUALLY MOVE ITS WAY INTO NW LA LATE THIS EVENING/OVERNIGHT BUT THE EVENTUAL STORM MODE SHOULD BE FOR A BROKEN LINE OF STRONG TO SEVERE THUNDERSTORMS TO DEVELOP ACROSS THE REGION...RAPIDLY EXPANDING AND SPREADING SOUTH AND EAST THROUGH THE NIGHT. DAMAGING WIND GUSTS...LARGE HAIL AND ISOLATED TORNADOES WILL CONTINUE TO BE A THREAT...WITH THE TORNADIC THREAT LIKELY ORIENTED NEAR WHERE THE WARM FRONT SETS UP LATER THIS EVENING...SOMEWHERE ACROSS NE TX INTO WEST CENTRAL OR NORTHWEST LOUISIANA. THE LEAD SHORTWAVE EJECTS NORTHWARD INTO THE CENTRAL PLAINS OVERNIGHT TONIGHT WITH NEAR ZONAL FLOW IN ITS WAKE SETTING UP ACROSS THE SOUTHERN PLAINS. THIS SHOULD RESULT IN A MUCH DRIER DAY ON SATURDAY BUT A STRONG PRESSURE GRADIENT WILL EXIST ACROSS THE REGION AS WELL. STRONG SOUTHWEST WINDS AND EVENTUAL SUNSHINE WILL ALLOW FOR SFC TEMPS TO WARM WELL INTO THE 80S ON SAT AS WELL AS SUN WITH SOME LOCATIONS LIKELY FLIRTING WITH THE 90 DEGREE MARK. MOISTURE BEGINS TO RETURN QUICKLY BACK INTO THE REGION FROM THE SOUTH DURING THE DAY SUNDAY INTO SUNDAY NIGHT AS YET ANOTHER UPPER TROUGH DIGS INTO THE SOUTHWEST CONUS AND CUTS OFF ACROSS THE FOUR CORNERS REGION LATE SUNDAY NIGHT. THIS RETURNING MOISTURE AND INSTABILITY WILL LIKELY RESULT IN ANOTHER RISK OF STRONG TO SEVERE THUNDERSTORMS ACROSS OUR REGION MONDAY INTO MONDAY NIGHT WITH THE UPPER TROUGH ONLY MAKING SLOW EASTWARD PROGRESS INTO CENTRAL OK BY TUE. THE GOOD NEWS IS BY THIS TIME...WE SHOULD BEGIN TO SEE DRY SLOTTING ALONG THE SOUTHERN FLANK OF THE CLOSED LOW WHICH SHOULD RESULT IN DRIER CONDITIONS TUESDAY AND ESPECIALLY WEDNESDAY THROUGH THE END OF THE WORK WEEK AS AS UPPER LEVEL RIDGING BEGINS TO TAKE OVER FROM THE WEST. PRELIMS TO FOLLOW...13. PREV DISCUSSION... /ISSUED 102 PM CDT FRI APR 24 2015/ AVIATION... MORNING IFR/LOW MVFR CIGS AND PATCHY FOG HAVE BEEN SLOW TO CLEAR OUT ACROSS LA/AR PORTIONS OF AREA. HOWEVER...CIGS HAVE LIFTED TO VFR ACROSS NE TX...AND BECMG SKC AT KLFK. AS TEMPS WARM TO AOB 80 DEGREES...EXPLOSIVE CONVECTION MAY OCCUR. VERY STG LOW LVL DIRECTIONAL SHEAR WILL BRING A THREAT FOR VERY LARGE HAIL AND POSSIBLE TORNADOES ACROSS NE TX BY AROUND 24/21-22Z...WITH WARM FRONT MOVG SLOWLY NWD ACROSS AREA. IN ADDITION...A SLOW MOVG SQUALL LINE TO DEVELOP LATER THIS EVE...AND BRING STG STRAIGHT LINE WINDS OVERNIGHT. WITH PASSAGE OF THIS UPPER TROUGH BRINGING LINE OF STORMS...WINDS BECMG SW 10 TO 20 KTS...AND VFR CONDITIONS TO RETURN TO AREA BY AROUND 25/15Z. VII && .PRELIMINARY POINT TEMPS/POPS... SHV 69 89 64 89 / 60 20 0 10 MLU 70 87 66 87 / 60 30 10 10 DEQ 62 86 51 85 / 80 10 0 10 TXK 68 87 60 85 / 80 10 0 10 ELD 68 85 60 84 / 60 20 0 10 TYR 69 89 63 88 / 60 10 0 10 GGG 68 88 63 88 / 60 10 0 10 LFK 70 89 65 89 / 60 30 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 05/05
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
326 PM CDT FRI APR 24 2015 .DISCUSSION... LATEST SFC ANALYSIS SHOWING A DEEPENING SFC LOW ACROSS SE CO INTO SW KS WITH A DRYLINE ACROSS THE TX/OK PNDL INTO W TX. A SOUTHEAST FLANKING WARM FRONT EXTENDED FROM THE SFC LOW AND SNAKED SOUTH AND EAST INTO CENTRAL OK TO JUST SOUTH OF DFW TO NEAR TYR TO ESF. THIS WARM FRONT HAS MOVED VERY LITTLE TODAY ACROSS S/CENTRAL LA BUT HAS SHOWN A GREATER TENDENCY TO MOVE NORTHWARD INTO NORTH CENTRAL TEXAS OVER THE LAST COUPLE HOURS. CLOUD COVER REMAINS VERY THICK AND ITS THIS CLOUD COVER THAT HAS TEMPERED DAYTIME HIGH TEMPS TODAY. ITS ALSO THIS CLOUD COVER THAT HAS NOT ALLOWED FOR MUCH IN THE WAY OF INSTABILITY. LATEST MESOANALYSIS ONLY SHOWING CAPE VALUES NEAR 1000J/KG ALONG AND SOUTHWEST OF THE SLOWLY RETURNING NORTHWARD WARM FRONT. SUPERCELL THUNDERSTORM THAT FORMED SOUTH OF OUR AREA EARLIER TODAY FORMED ALONG THE WARM FRONT AND THE BEST UPPER LEVEL SUPPORT WHICH IS MEAGER AT BEST...EXISTS OUT WEST WHERE TORNADO WATCH #100 WAS JUST ISSUED FOR PORTIONS OF CENTRAL AND N TX. THE LATEST WRF OUTPUT HAS SHOWN A TENDENCY TO LIFT THE WARM FRONT TOO FAR NORTH AND THUS ITS SOLUTION WAS DISCOUNTED. HAVE INSTEAD GONE WITH A MODEL BLEND OF THE HRRR FOR THE VERY SHORT TERM...FOLLOWED BY A GFS/ECMWF BLEND BEYOND TONIGHT. HAVING SAID THAT...THE LATEST HRRR SHOWS CONVECTION DEVELOPING RAPIDLY NEAR AND NORTH OF THE I-20 CORRIDOR OF N TX LATER THIS EVENING WITH SOME OF THESE STORMS LIKELY EXHIBITING DISCRETE CHARACTERISTICS AS THEY MOVE EASTWARD INTO OUR NW ZONES. SOME OF THIS STRONG/SEVERE CONVECTION COULD EVENTUALLY MOVE ITS WAY INTO NW LA LATE THIS EVENING/OVERNIGHT BUT THE EVENTUAL STORM MODE SHOULD BE FOR A BROKEN LINE OF STRONG TO SEVERE THUNDERSTORMS TO DEVELOP ACROSS THE REGION...RAPIDLY EXPANDING AND SPREADING SOUTH AND EAST THROUGH THE NIGHT. DAMAGING WIND GUSTS...LARGE HAIL AND ISOLATED TORNADOES WILL CONTINUE TO BE A THREAT...WITH THE TORNADIC THREAT LIKELY ORIENTED NEAR WHERE THE WARM FRONT SETS UP LATER THIS EVENING...SOMEWHERE ACROSS NE TX INTO WEST CENTRAL OR NORTHWEST LOUISIANA. THE LEAD SHORTWAVE EJECTS NORTHWARD INTO THE CENTRAL PLAINS OVERNIGHT TONIGHT WITH NEAR ZONAL FLOW IN ITS WAKE SETTING UP ACROSS THE SOUTHERN PLAINS. THIS SHOULD RESULT IN A MUCH DRIER DAY ON SATURDAY BUT A STRONG PRESSURE GRADIENT WILL EXIST ACROSS THE REGION AS WELL. STRONG SOUTHWEST WINDS AND EVENTUAL SUNSHINE WILL ALLOW FOR SFC TEMPS TO WARM WELL INTO THE 80S ON SAT AS WELL AS SUN WITH SOME LOCATIONS LIKELY FLIRTING WITH THE 90 DEGREE MARK. MOISTURE BEGINS TO RETURN QUICKLY BACK INTO THE REGION FROM THE SOUTH DURING THE DAY SUNDAY INTO SUNDAY NIGHT AS YET ANOTHER UPPER TROUGH DIGS INTO THE SOUTHWEST CONUS AND CUTS OFF ACROSS THE FOUR CORNERS REGION LATE SUNDAY NIGHT. THIS RETURNING MOISTURE AND INSTABILITY WILL LIKELY RESULT IN ANOTHER RISK OF STRONG TO SEVERE THUNDERSTORMS ACROSS OUR REGION MONDAY INTO MONDAY NIGHT WITH THE UPPER TROUGH ONLY MAKING SLOW EASTWARD PROGRESS INTO CENTRAL OK BY TUE. THE GOOD NEWS IS BY THIS TIME...WE SHOULD BEGIN TO SEE DRY SLOTTING ALONG THE SOUTHERN FLANK OF THE CLOSED LOW WHICH SHOULD RESULT IN DRIER CONDITIONS TUESDAY AND ESPECIALLY WEDNESDAY THROUGH THE END OF THE WORK WEEK AS AS UPPER LEVEL RIDGING BEGINS TO TAKE OVER FROM THE WEST. PRELIMS TO FOLLOW...13. && .PREV DISCUSSION... /ISSUED 102 PM CDT FRI APR 24 2015/ AVIATION... MORNING IFR/LOW MVFR CIGS AND PATCHY FOG HAVE BEEN SLOW TO CLEAR OUT ACROSS LA/AR PORTIONS OF AREA. HOWEVER...CIGS HAVE LIFTED TO VFR ACROSS NE TX...AND BECMG SKC AT KLFK. AS TEMPS WARM TO AOB 80 DEGREES...EXPLOSIVE CONVECTION MAY OCCUR. VERY STG LOW LVL DIRECTIONAL SHEAR WILL BRING A THREAT FOR VERY LARGE HAIL AND POSSIBLE TORNADOES ACROSS NE TX BY AROUND 24/21-22Z...WITH WARM FRONT MOVG SLOWLY NWD ACROSS AREA. IN ADDITION...A SLOW MOVG SQUALL LINE TO DEVELOP LATER THIS EVE...AND BRING STG STRAIGHT LINE WINDS OVERNIGHT. WITH PASSAGE OF THIS UPPER TROUGH BRINGING LINE OF STORMS...WINDS BECMG SW 10 TO 20 KTS...AND VFR CONDITIONS TO RETURN TO AREA BY AROUND 25/15Z. VII && .PRELIMINARY POINT TEMPS/POPS... SHV 69 89 64 89 / 60 20 0 10 MLU 70 87 66 87 / 60 30 10 10 DEQ 62 86 51 85 / 80 10 0 10 TXK 68 87 60 85 / 80 10 0 10 ELD 68 85 60 84 / 60 20 0 10 TYR 69 89 63 88 / 60 10 0 10 GGG 68 88 63 88 / 60 10 0 10 LFK 70 89 65 89 / 60 30 10 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ VII/13
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
102 PM CDT FRI APR 24 2015 .AVIATION... MORNING IFR/LOW MVFR CIGS AND PATCHY FOG HAVE BEEN SLOW TO CLEAR OUT ACROSS LA/AR PORTIONS OF AREA. HOWEVER...CIGS HAVE LIFTED TO VFR ACROSS NE TX...AND BECMG SKC AT KLFK. AS TEMPS WARM TO AOB 80 DEGREES...EXPLOSIVE CONVECTION MAY OCCUR. VERY STG LOW LVL DIRECTIONAL SHEAR WILL BRING A THREAT FOR VERY LARGE HAIL AND POSSIBLE TORNADOES ACROSS NE TX BY AROUND 24/21-22Z...WITH WARM FRONT MOVG SLOWLY NWD ACROSS AREA. IN ADDITION...A SLOW MOVG SQUALL LINE TO DEVELOP LATER THIS EVE...AND BRING STG STRAIGHT LINE WINDS OVERNIGHT. WITH PASSAGE OF THIS UPPER TROUGH BRINGING LINE OF STORMS...WINDS BECMG SW 10 TO 20 KTS...AND VFR CONDITIONS TO RETURN TO AREA BY AROUND 25/15Z./VII/. && .PREV DISCUSSION... /ISSUED 1032 AM CDT FRI APR 24 2015/ DISCUSSION... TWO AREAS OF CONCERN THIS MORNING ACROSS THE REGION...THE FIRST BEING INCREASING COVERAGE OF THUNDERSTORMS ACROSS SOUTHEAST/EAST CENTRAL TX AND THE SECOND BEING INCREASING COVERAGE NORTH OF THE I-20 CORRIDOR. THE FIRST IS DUE IN PART TO A WEAK PERTURBATION IN SW FLOW ALOFT SWINGING NE FROM CENTRAL TX. THIS UPPER LEVEL FEATURE ALSO HAS SOME SURFACE SUPPORT AS AN ANALYSIS SHOWS A WARM FRONT NEARLY STAGNATED FROM N TX...SNAKING ITS WAY SOUTHEAST ACROSS THE LOWER TOLEDO BEND RESERVOIR INTO SOUTHEAST LA. THIS WARM FRONT IS EXPECTED TO COME SLOWLY NORTHWARD TODAY...PERHAPS AS FAR NORTH AS THE I-20 CORRIDOR OF N LA. THE SECOND AREA OF CONCERN IS OF A MORE ELEVATED NATURE THIS MORNING WITH COVERAGE NORTH OF THE I-20 CORRIDOR. THIS ACTIVITY IS WELL NORTH OF THE WARM FRONT BUT IS SITUATED AGAIN WITH STRONGER PERTURBATIONS IN THE SOUTHWEST FLOW ALOFT. FOR THE UPDATE THIS MORNING...RAISED RAIN CHANCES WHERE THESE TWO ENHANCED AREAS OF PRECIP WERE OBSERVED. OUR SEVERE WEATHER THREAT FOR LATER TODAY/THIS EVENING WILL DEPEND GREATLY ON JUST HOW MUCH WE ARE ABLE TO DESTABILIZE AND HOW FAR NORTH THE WARM FRONT MAKES IT INTO OUR REGION FROM THE SOUTH. THE HRRR SHOWS A BREAK IN THE WIDESPREAD ACTIVITY LATER THIS AFTN ACROSS THE SOUTHERN HALF OF NE TX IN THE WAKE OF THE FIRST DISTURBANCE AND THIS MAY BE THE BREAK NECESSARY FOR AT LEAST OUR SOUTHERN HALF TO WARM UP AS THIS AREA SHOULD BE WELL INTO THE WARM SECTOR BY THIS TIME. DEEP LAYER SHEAR IS SUPPORTIVE OF SUPERCELLS AND EVENTUAL BOWING LINE SEGMENTS IF WE CAN GET THE INSTABILITY TO INCREASE LATER TODAY. LOW LEVEL SHEAR WILL ALSO BE SUPPORTIVE OF A FEW TORNADOES...ESPECIALLY ALONG AND JUST SOUTH OF THE WARM FRONT LATE THIS AFTERNOON/THIS EVENING. UPDATE OUT SHORTLY...13. && .PRELIMINARY POINT TEMPS/POPS... SHV 75 70 89 64 / 80 80 20 0 MLU 74 71 90 64 / 70 80 30 10 DEQ 67 63 86 55 / 80 70 10 0 TXK 70 69 89 60 / 80 80 10 0 ELD 70 69 90 60 / 80 80 20 0 TYR 78 70 89 64 / 80 50 10 0 GGG 77 69 90 64 / 80 70 10 0 LFK 80 71 91 67 / 80 50 30 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1032 AM CDT FRI APR 24 2015 .DISCUSSION... TWO AREAS OF CONCERN THIS MORNING ACROSS THE REGION...THE FIRST BEING INCREASING COVERAGE OF THUNDERSTORMS ACROSS SOUTHEAST/EAST CENTRAL TX AND THE SECOND BEING INCREASING COVERAGE NORTH OF THE I-20 CORRIDOR. THE FIRST IS DUE IN PART TO A WEAK PERTURBATION IN SW FLOW ALOFT SWINGING NE FROM CENTRAL TX. THIS UPPER LEVEL FEATURE ALSO HAS SOME SURFACE SUPPORT AS AN ANALYSIS SHOWS A WARM FRONT NEARLY STAGNATED FROM N TX...SNAKING ITS WAY SOUTHEAST ACROSS THE LOWER TOLEDO BEND RESERVOIR INTO SOUTHEAST LA. THIS WARM FRONT IS EXPECTED TO COME SLOWLY NORTHWARD TODAY...PERHAPS AS FAR NORTH AS THE I-20 CORRIDOR OF N LA. THE SECOND AREA OF CONCERN IS OF A MORE ELEVATED NATURE THIS MORNING WITH COVERAGE NORTH OF THE I-20 CORRIDOR. THIS ACTIVITY IS WELL NORTH OF THE WARM FRONT BUT IS SITUATED AGAIN WITH STRONGER PERTURBATIONS IN THE SOUTHWEST FLOW ALOFT. FOR THE UPDATE THIS MORNING...RAISED RAIN CHANCES WHERE THESE TWO ENHANCED AREAS OF PRECIP WERE OBSERVED. OUR SEVERE WEATHER THREAT FOR LATER TODAY/THIS EVENING WILL DEPEND GREATLY ON JUST HOW MUCH WE ARE ABLE TO DESTABILIZE AND HOW FAR NORTH THE WARM FRONT MAKES IT INTO OUR REGION FROM THE SOUTH. THE HRRR SHOWS A BREAK IN THE WIDESPREAD ACTIVITY LATER THIS AFTN ACROSS THE SOUTHERN HALF OF NE TX IN THE WAKE OF THE FIRST DISTURBANCE AND THIS MAY BE THE BREAK NECESSARY FOR AT LEAST OUR SOUTHERN HALF TO WARM UP AS THIS AREA SHOULD BE WELL INTO THE WARM SECTOR BY THIS TIME. DEEP LAYER SHEAR IS SUPPORTIVE OF SUPERCELLS AND EVENTUAL BOWING LINE SEGMENTS IF WE CAN GET THE INSTABILITY TO INCREASE LATER TODAY. LOW LEVEL SHEAR WILL ALSO BE SUPPORTIVE OF A FEW TORNADOES...ESPECIALLY ALONG AND JUST SOUTH OF THE WARM FRONT LATE THIS AFTERNOON/THIS EVENING. UPDATE OUT SHORTLY...13. && .PREV DISCUSSION... /ISSUED 813 AM CDT FRI APR 24 2015/ AVIATION... FOR THE 24/12Z TAFS...IFR/MVFR CIGS FOR MANY ATTM WITH WIDE SPREAD SHWRS/TSTMS N ALONG I-30 AS A WARM FRONT IS RETURNING NORTHWARD. EXPECT INTENSE CONVECTION DEVELOPING DURING THE AFTERNOON IN OUR CWA FM W TO E AS A COLD FRONT SHIFTS EWRD ACROSS TX/OK AT PEAK HEATING...DRIVING A SQ LINE(S) OF TSTMS DURING THE EVENING HOURS. OUR ELY SFC WINDS WILL GRADUALLY BE VEERING TO S/SELY THIS CYCLE. ALOFT...OUR CLIMB WINDS ARE ALREADY S/SE 5-25KTS TO 2KFT...THEN VEER TO ALL SW/W ALOFT 20-50KTS TO 20KFT...AND DUE WEST AT 75KTS BY FL240. /24/ && .PRELIMINARY POINT TEMPS/POPS... SHV 75 70 89 64 / 80 80 20 0 MLU 74 71 90 64 / 70 80 30 10 DEQ 67 63 86 55 / 80 70 10 0 TXK 70 69 89 60 / 80 80 10 0 ELD 70 69 90 60 / 80 80 20 0 TYR 78 70 89 64 / 80 50 10 0 GGG 77 69 90 64 / 80 70 10 0 LFK 80 71 91 67 / 80 50 30 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 24/13
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
823 PM EDT SAT APR 25 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND OFF THE COAST SUNDAY MORNING. THE LOW REMAINS OFFSHORE AS HIGH PRESSURE GRADUALLY BUILDS IN FROM THE WEST FOR THE FIRST HALF OF THE WEEK. ANOTHER LOW MAY IMPACT THE REGION FOR THE LATTER HALF OF THE WEEK. && .NEAR TERM /THROUGH SUNDAY/... AS OF 00Z...RAIN EXTENDS FROM THE LOWER GREAT LAKES TO THE DELMARVA COAST ALONG AN AREA OF CONVERGENCE ALOFT. A SURFACE LOW IS LOCATED ACROSS THE TN VALLEY. ALONG THE LEADING EDGE OF THE RAIN MOVING NORTHWARD...DEWPTS DRASTICALLY DROP OFF INTO THE UPPER 20S/30S. AS THE RAINDROPS MOVE INTO THE DRY ENVIRONMENT...THEY COOL IN THE LOWER 1-2K FEET AND RE-FREEZE RESULTING IN SLEET BEING OBSERVED NEAR THE LEADING EDGE. AS RAIN MOVES NORTHWARD DEWPTS WILL RISE INTO THE 30S/40S TONIGHT. NO SLEET ACCUMULATION IS EXPECTED. AS THE LOW MOVES EASTWARD THE BAND OF RAIN CURRENTLY OVER THE MID-ATLANTIC WILL ALSO MOVE EASTWARD. THIS AREA OF RAIN IS EXPECTED TO TAPER OFF AFTER 6Z TONIGHT MOVING EAST OF I-95 BY 10Z SUNDAY. TEMPERATURES WILL NOT FALL MUCH OVERNIGHT AND BASICALLY TRENDED MIN TEMPS TO ADJUSTED MET GUIDANCE. FORECAST RAINFALL AMOUNTS GENERALLY LINE UP PRETTY WELL WITH WPC QPF AMOUNTS AND WILL BE GENERALLY HEAVIER ACROSS THE SW PORTION WITH AMOUNTS AROUND ONE HALF INCH...DC METRO AROUND ONE- QUARTER OF AN INCH...BALTIMORE BETWEEN 1-2 TENTHS. HI RES CAM MODELS SHOW GOOD AGREEMENT WITH 12Z NAM/GFS/SREF ON TIMING OF PRECIP ACROSS AREA. LATEST HRRR GUIDANCE SUGGEST THE PRECIP COULD EVEN BE MORE SCATTERED IN COVERAGE THIS EVENING. FOR SUNDAY...THERE COULD BE LINGERING LIGHT PRECIP ACROSS THE SRN TIER OF THE CWA JUST AFTER 12Z...BUT CLOUDS AND PRECIP WILL PUSH SOUTH AS HIGH PRESSURE BUILDS INTO THE REGION FROM THE GREAT LAKES. HIGH TEMPS STILL COOL FOR THIS TIME OF YEAR...AND USED A BLEND OF MOS/ADJ MAV. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... REGION REMAINS POSITIONED UNDER UPPER LVL LOW CENTERED OVER THE CANADIAN MARITIMES WHILE SFC LOW SETTLES WELL OFFSHORE TO START THE WORK WEEK. GENERALLY EXPECTING DRY CONDITIONS SUN NIGHT WITH A BREAK IN THE SHORTWAVE ENERGY...THOUGH A SFC TROF COULD GENERATE ISO SHOWERS SECOND HALF OF THE NIGHT. TEMPS DROPPING INTO THE 30S FOR LOWS SUN NIGHT COULD RESULT IN ANY PCPN NEAR DAYBREAK BEING A RAIN/SNOW OR EVEN ALL SNOW...WITH LITTLE TO NO ACCUM. THE REGION WILL BE SANDWICHED BETWEEN HIGH PRESSURE OVER THE GREAT LAKES AND THE LOW OFFSHORE MONDAY...RESULTING IN ELEVATED WINDS...WITH GUSTS 25-30 MPH. POPS INCREASE AFTR 12Z MON AS NEXT SHORTWAVE/VORT MAX ROUNDS THE LOW...WITH THE BETTER CHC WESTERN AND EASTERN FRINGES OF THE CWA. THE STRONG SHORTWAVE WILL EXTEND ACROSS THE MID ATLANTIC FOR MOST OF THE DAY...PRODUCING SCT SHOWERS. PCPN TAPERS OFF MON EVENING AS UPPER LVL LOW PIVOTS OFFSHORE. AS THE HIGH BUILDS IN...EXPECTING TO SEE WARMING TEMPS...WITH TEMPS NEARING NORMAL BY MON NIGHT. && .LONG TERM /TUESDAY THROUGH SATURDAY/... DESPITE THE COOL START AND CONTINUED CAA BEHIND THE COLD FRONT...TEMPS WILL REBOUND A FEW DEGREES TUE AS DECREASING CLOUDS ALLOW THE LATE APRIL SUN TO DO ITS WORK. THIS SLOW WARMING TREND CONTINUES INTO WED...WITH TEMPS BACK TO NEAR NORMAL...AS A WEAK AREA OF HIGH PRESSURE BUILDS IN. MODEL DIVERGENCE INCREASES SUBSTANTIALLY BY LATE WED INTO THU WITH REGARDS TO DEVELOPING LOW OVER GOM. LATEST MODEL GUIDANCE APPEARS TO SHUNT MAIN IMPACTS TO OUR SOUTH...WITH LITTLE QPF OVER CWA. 12Z GFS FAR DIFFERENT FROM 00Z ECMWF...AS GFS HAS NO COASTAL LOW OFF THE CAROLINA COAST AND ECMWF DOES. HAVE LOWERED POPS SOME FOR THU...ALTHOUGH FOR CONSISTENCY AND TO AVOID JUMPING ON ONE MODEL CYCLE STILL KEPT CHC POPS...ALTHOUGH THAT MIGHT BE TOO HIGH. HIGH PRESSURE RETURNS BY FRIDAY...BRINGING NEAR NORMAL TEMPS. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... -RA EXPECTED AT THE TERMINALS THIS EVENING BEFORE TAPERING OFF AFTER 6Z TONIGHT. CIGS WILL CONTINUE TO LOWER TONIGHT. A BRIEF PERIOD OF IFR CONDITIONS ARE POSSIBLE 3-6Z BEFORE DRIER AIR MOVES INTO THE TERMINALS BUT AT THIS TIME CARRYING MVFR CIGS. CHO WILL LIKELY SEE THE MOST MOISTURE ALOFT AND THEREFORE IFR CIGS ARE EXPECTED TONIGHT. LIGHT S-SW WINDS WILL BECOME N TONIGHT AND INTO SUNDAY MORNING. WINDS SHOULD STAY LIGHT...LESS THAN 6KTS. VFR CONDITIONS SUN-SUN NIGHT. SUB-VFR CONDITIONS PSBL MON WITH ANY RAIN SHOWER. GUSTY NW WINDS WITH GUSTS 20-25 KTS PSBL AS WELL DURING THE DAY MON...DIMINISHING AFTR SUNSET. MVFR CIGS MAY LINGER THRU MON NIGHT. NOT EXPECTING AVIATION CONCERNS TUE/WED WITH VFR CONDITIONS. && .MARINE... RAIN WILL CONTINUE TO OVERSPREAD THE WATERS THIS EVENING. WINDS REMAIN LESS THAN 10 KTS THROUGH SUN MORNING...INCREASING SUN AFTN. GUSTS COULD BRIEFLY TOUCH 18-20 KTS SUN AFTN WITH NORTHERLY CHANNELING. SUB-SCA CONDITIONS INITIALLY SUN EVENING...WITH INCRSG WINDS OVERNIGHT. SCA CONDITIONS WITH GUSTS UP TO 20 KTS AS EARLY AS THE SECOND HALF OF SUN NIGHT...BCMG MORE LIKELY AFTR DAYBREAK MON. GUSTS UP TO 30 KTS PSBL ON THE CHESAPEAKE BAY DURING THE DAY. SCA GUSTS CONTINUE THRU MON NIGHT. SCA IS POSSIBLE TUE UNTIL THE PRESSURE GRADIENT WEAKENS WITH DEPARTING LOW. PRESSURE GRADIENT RELAXES ENOUGH FOR A RETURN TO LIGHT WINDS BY WED. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...SEARS NEAR TERM...HAS/SMZ SHORT TERM...SEARS/SMZ LONG TERM...MSE AVIATION...SEARS/HAS/MSE/SMZ MARINE...SEARS/HAS/MSE/SMZ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
347 PM EDT FRI APR 24 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 241 PM EDT FRI APR 24 2015 FLOW ALOFT BRIEFLY HAS BECOME WESTERLY WHICH IS ALLOWING WARM ADVECTION OCCURRING NORTH OF WEAK SFC WARM FRONT OVER SOUTHERN MINNESOTA TO AFFECT FAR WESTERN GREAT LAKES. LOW-LEVELS BLO H85 PER 12Z SOUNDINGS FM GRB/INL/MPX REMAIN QUITE DRY...BUT MOISTURE AND WARM ADVECTION MAINLY AT H7 IS DRIVING AREA OF SCT LIGHT SHOWERS OVER NORTHWEST WI. EVEN SOME SNOW WAS REPORTED IN NORTHEAST MINNESOTA EARLIER TODAY AS TEMPS WERE IN THE 30S AS THE PRECIP BEGAN. BASED ON WHERE RAP/NAM SHOW NOSE OF H7 MOISTURE TRANSPORT INTO THIS EVENING...SOME OF THE SHRA OVER NORTHWEST WI MAY CLIP SW UPR MICHIGAN THROUGH MIDNIGHT. GREATEST CHANCES FM IRONWOOD TO IRON RIVER. WEAK FORCING ALOFT AND PERSISTENT DRY LOW-LEVELS WILL PROHIBIT THE PRECIP FM MAKING IT VERY FAR TO THE NORTH AND EAST OF THOSE AREAS. LATEST HRRR MODEL RUNS ARE PICKING UP ON THIS...SHOWING ANY SIMULATED REFLECTIVITY AT 1KM OF NOTE FADING AS IT MOVES INTO SCNTRL UPR MICHIGAN. AS TEMPS COOL ENOUGH IN BLYR AFTER SUNSET...MAY SEE RAIN TRY TO TURN TO SNOW BRIEFLY BEFORE THE WANING FORCING ALLOWS THIS PRECIP TO END. NOT EXPECTING ANYTHING MORE THAN A COATING OF SNOW ACCUMULATION IF IT OCCURS AT ALL. TEMPS TONIGHT WILL BE COOLEST IN THE EAST /UPR TEENS TO LOW 20S/ CLOSER TO SFC HIGH AND WHERE SKIES STAY MOSTLY CLEAR. ELSEWHERE EXPECT READINGS IN UPR 20S TO MID 30S...WARMEST WEST. MID CLOUDS GRADUALLY FADE AWAY ON SATURDAY AS SFC HIGH PRESSURE BUILDS IN FM HUDSON BAY. NORTHERLY GRADIENT WINDS TIED INTO THE HIGH WILL KEEP AREAS NEAR LK SUPERIOR SHORE STUCK IN THE 30S DESPITE THE INCREASING SUNSHINE. WARMEST TEMPS INTO THE LOW 50S WILL BE ALONG WI BORDER AND ALSO NEAR LK MICHIGAN WITH NORTH WINDS COMING OFF THE LAND OF EAST HALF OF UPR MICHIGAN. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 342 PM EDT FRI APR 24 2015 SAT NIGHT AND SUN...SFC RIDGING AND DRY WEATHER IS EXPECTED TO DOMINATE THE WRN GREAT LAKES AS A MID LEVEL RIDGE BUILDS TOWARD MN AND NW ONTARIO AND TROUGH LINGERS FROM NRN NEW ENGLAND THROUGH THE ERN GREAT LAKES. WITH LIGHT NE TO N LOW LEVEL FLOW...TEMPS WILL REMAIN BELOW NORMAL...ESPECIALLY NEAR LAKE SUPERIOR WHERE HIGHS WILL REACH ONLY INTO THE LOWER 40S. READINGS TO AROUND 50 WILL PREVAIL OVER THE SOUTH HALF. THE SFC HIGH WILL CONTINUE TO RIDGE S INTO UPPER MI ON MON...SO MON WILL BE SIMILAR TO SUN. HOWEVER...WITH THE PRES GRADIENT WEAKENING AND A SLIGHT MODERATION OF AIR MASS...MAX TEMPS MON SHOULD BE SEVERAL DEGREES HIGHER THAN SUN...ESPECIALLY IN THE INTERIOR. MEDIUM RANGE MODELS INDICATE A SHORTWAVE MOVING ACROSS THE NRN PLAINS MON NIGHT. AS MID/UPPER RIDGE BEGINS BUILDING OVER THE ROCKIES...THIS WAVE MAY END UP DIVING SE OR S TOWARD A SRN TROF OVER TX/LWR MISSISSIPPI VALLEY REGION PER 12Z RUNS OF GFS AND GEM AND 23/12Z ECMWF...RESULTING IN CONTINUED DRY WEATHER HERE. THE 24/00Z AND 24/12Z RUNS OF THE ECMWF HAVE TRENDED STRONGER WITH THE SHORTWAVE SHOWING A MORE AGGRESSIVE EASTWARD PROGRESSION BEFORE DIVING THE SHORTWAVE SE. THIS SOLN MAY RESULT IN SOME LIGHT SHRA SPREADING INTO UPPER MI TUE INTO WED MORNING. GIVEN THAT LATEST ECMWF STILL SHOWS THE MORE AGGRESSIVE EASTWARD PROGRESSION WITH SHORTWAVE WILL MAINTAIN SLIGHT CHC POPS FOR SHRA OVER THE CWA TUE INTO WED. CAA IN N-NE FLOW AHEAD OF BUILDING SFC HIGH FM CANADA AS DEPICTED BY 12Z ECMWF WL KEEP TEMPS COOLER WED INTO WED NIGHT PROBABLY SIMILAR TO EXPECTED BELOW NORMAL READINGS THIS WEEKEND. THU-FRI...SFC HIGH PRES BUILDS BACK OVER THE REGION AND SINCE BOTH 12Z GFS AND ECMWF HAVE TRENDED FARTHER NORTH WITH SERIES OF SHORTWAVES MOVING ACROSS SCNTRL CANADA EXPECT GENERALLY DRY CONDITIONS TO PREVAIL. GENERAL TREND OF 00Z MEDIUM RANGE GUIDANCE IS FOR UPSTREAM MID-UPR LVL RIDGING OVER THE WRN CONUS TO BE A BIT MORE PRONOUNCED WHICH RESULTS IN A SHARPER NW FLOW DEVELOPING INTO THE UPPER LAKES. THIS WOULD TEMPER THE WARMUP INTO THE WRN GREAT LAKES FOR LATE WEEK AND MAY RESULT IN TEMPS CLOSER TO NORMAL INSTEAD OF ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 119 PM EDT FRI APR 24 2015 HIGH PRESSURE AND DRY CONDITIONS SHOULD REMAIN IN CONTROL OF ALL 3 TAF SITES THROUGH THE PERIOD...WITH VFR CEILINGS/VIS. THE ONLY SMALL EXCEPTION WILL BE IWD LATE THIS AFTN INTO EARLY THIS EVENING...WHERE SOME LIGHT SHRA MAY DROP CONDITIONS TO MVFR. WINDS WILL BE LIGHT INTO SATURDAY. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 241 PM EDT FRI APR 24 2015 HIGH PRESSURE WILL BE THE DOMINANT WEATHER FACTOR OVER THE UPPER GREAT LAKES THIS WEEKEND AND THROUGH MUCH OF NEXT WEEK. OVERALL THE WINDS WILL STAY AT OR BLO 20 KTS. THE ONE MAIN EXCEPTION WILL BE TONIGHT AND SATURDAY OVER WESTERN LK SUPERIOR WHERE EAST TO NORTHEAST WINDS OF 20-25 KTS WITH GUSTS TO AROUND 30 KTS ARE EXPECTED AS STRONGER HIGH PRESSURE AREA INITIALLY BUILDS OVER THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...VOSS AVIATION...JLA MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
334 PM EDT FRI APR 24 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 241 PM EDT FRI APR 24 2015 FLOW ALOFT BRIEFLY HAS BECOME WESTERLY WHICH IS ALLOWING WARM ADVECTION OCCURRING NORTH OF WEAK SFC WARM FRONT OVER SOUTHERN MINNESOTA TO AFFECT FAR WESTERN GREAT LAKES. LOW-LEVELS BLO H85 PER 12Z SOUNDINGS FM GRB/INL/MPX REMAIN QUITE DRY...BUT MOISTURE AND WARM ADVECTION MAINLY AT H7 IS DRIVING AREA OF SCT LIGHT SHOWERS OVER NORTHWEST WI. EVEN SOME SNOW WAS REPORTED IN NORTHEAST MINNESOTA EARLIER TODAY AS TEMPS WERE IN THE 30S AS THE PRECIP BEGAN. BASED ON WHERE RAP/NAM SHOW NOSE OF H7 MOISTURE TRANSPORT INTO THIS EVENING...SOME OF THE SHRA OVER NORTHWEST WI MAY CLIP SW UPR MICHIGAN THROUGH MIDNIGHT. GREATEST CHANCES FM IRONWOOD TO IRON RIVER. WEAK FORCING ALOFT AND PERSISTENT DRY LOW-LEVELS WILL PROHIBIT THE PRECIP FM MAKING IT VERY FAR TO THE NORTH AND EAST OF THOSE AREAS. LATEST HRRR MODEL RUNS ARE PICKING UP ON THIS...SHOWING ANY SIMULATED REFLECTIVITY AT 1KM OF NOTE FADING AS IT MOVES INTO SCNTRL UPR MICHIGAN. AS TEMPS COOL ENOUGH IN BLYR AFTER SUNSET...MAY SEE RAIN TRY TO TURN TO SNOW BRIEFLY BEFORE THE WANING FORCING ALLOWS THIS PRECIP TO END. NOT EXPECTING ANYTHING MORE THAN A COATING OF SNOW ACCUMULATION IF IT OCCURS AT ALL. TEMPS TONIGHT WILL BE COOLEST IN THE EAST /UPR TEENS TO LOW 20S/ CLOSER TO SFC HIGH AND WHERE SKIES STAY MOSTLY CLEAR. ELSEWHERE EXPECT READINGS IN UPR 20S TO MID 30S...WARMEST WEST. MID CLOUDS GRADUALLY FADE AWAY ON SATURDAY AS SFC HIGH PRESSURE BUILDS IN FM HUDSON BAY. NORTHERLY GRADIENT WINDS TIED INTO THE HIGH WILL KEEP AREAS NEAR LK SUPERIOR SHORE STUCK IN THE 30S DESPITE THE INCREASING SUNSHINE. WARMEST TEMPS INTO THE LOW 50S WILL BE ALONG WI BORDER AND ALSO NEAR LK MICHIGAN WITH NORTH WINDS COMING OFF THE LAND OF EAST HALF OF UPR MICHIGAN. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 334 PM EDT FRI APR 24 2015 SAT NIGHT AND SUN...SFC RIDGING AND DRY WEATHER IS EXPECTED TO DOMINATE THE WRN GREAT LAKES AS A MID LEVEL RIDGE BUILDS TOWARD MN AND NW ONTARIO AND TROUGH LINGERS FROM NRN NEW ENGLAND THROUGH THE ERN GREAT LAKES. WITH LIGHT NE TO N LOW LEVEL FLOW...TEMPS WILL REMAIN BELOW NORMAL...ESPECIALLY NEAR LAKE SUPERIOR WHERE HIGHS WILL REACH ONLY INTO THE LOWER 40S. READINGS TO AROUND 50 WILL PREVAIL OVER THE SOUTH HALF. THE SFC HIGH WILL CONTINUE TO RIDGE S INTO UPPER MI ON MON...SO MON WILL BE SIMILAR TO SUN. HOWEVER...WITH THE PRES GRADIENT WEAKENING AND A SLIGHT MODERATION OF AIR MASS...MAX TEMPS MON SHOULD BE SEVERAL DEGREES HIGHER THAN SUN...ESPECIALLY IN THE INTERIOR. MEDIUM RANGE MODELS INDICATE A SHORTWAVE MOVING ACROSS THE NRN PLAINS MON NIGHT. AS MID/UPPER RIDGE BEGINS BUILDING OVER THE ROCKIES...THIS WAVE MAY END UP DIVING SE OR S TOWARD A SRN TROF OVER TX/LWR MISSISSIPPI VALLEY REGION PER 12Z RUNS OF GFS AND GEM AND 23/12Z ECMWF...RESULTING IN CONTINUED DRY WEATHER HERE. THE 24/00Z AND 24/12Z RUNS OF THE ECMWF HAVE TRENDED STRONGER WITH THE SHORTWAVE SHOWING A MORE AGGRESSIVE EASTWARD PROGRESSION BEFORE DIVING THE SHORTWAVE SE. THIS SOLN MAY RESULT IN SOME LIGHT SHRA SPREADING INTO UPPER MI TUE INTO WED MORNING. GIVEN THAT LATEST ECMWF STILL SHOWS THE MORE AGGRESSIVE EASTWARD PROGRESSION WITH SHORTWAVE WILL MAINTAIN SLIGHT CHC POPS FOR SHRA OVER THE CWA TUE INTO WED. N-NE FLOW AHEAD OF BUILDING SFC HIGH FM CANADA WL KEEP TEMPS COOLER WED INTO WED NIGHT SIMILAR TO EXPECTED BELOW NORMAL READINGS THIS WEEKEND. THU-FRI...SFC HIGH PRES BUILDS BACK OVER THE REGION AND SINCE BOTH 12Z GFS AND ECMWF HAVE TRENDED FARTHER NORTH WITH SERIES OF SHORTWAVES MOVING ACROSS SCNTRL CANADA EXPECT GENERALLY DRY CONDITIONS TO PREVAIL. GENERAL TREND OF 00Z MEDIUM RANGE GUIDANCE IS FOR UPSTREAM MID-UPR LVL RIDGING OVER THE WRN CONUS TO BE A BIT MORE PRONOUNCED WHICH RESULTS IN A SHARPER NW FLOW DEVELOPING INTO THE UPPER LAKES. THIS WOULD TEMPER THE WARMUP INTO THE WRN GREAT LAKES FOR LATE WEEK AND MAY RESULT IN TEMPS CLOSER TO NORMAL INSTEAD OF ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 119 PM EDT FRI APR 24 2015 HIGH PRESSURE AND DRY CONDITIONS SHOULD REMAIN IN CONTROL OF ALL 3 TAF SITES THROUGH THE PERIOD...WITH VFR CEILINGS/VIS. THE ONLY SMALL EXCEPTION WILL BE IWD LATE THIS AFTN INTO EARLY THIS EVENING...WHERE SOME LIGHT SHRA MAY DROP CONDITIONS TO MVFR. WINDS WILL BE LIGHT INTO SATURDAY. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 241 PM EDT FRI APR 24 2015 HIGH PRESSURE WILL BE THE DOMINANT WEATHER FACTOR OVER THE UPPER GREAT LAKES THIS WEEKEND AND THROUGH MUCH OF NEXT WEEK. OVERALL THE WINDS WILL STAY AT OR BLO 20 KTS. THE ONE MAIN EXCEPTION WILL BE TONIGHT AND SATURDAY OVER WESTERN LK SUPERIOR WHERE EAST TO NORTHEAST WINDS OF 20-25 KTS WITH GUSTS TO AROUND 30 KTS ARE EXPECTED AS STRONGER HIGH PRESSURE AREA INITIALLY BUILDS OVER THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...VOSS AVIATION...JLA MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
241 PM EDT FRI APR 24 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 241 PM EDT FRI APR 24 2015 FLOW ALOFT BRIEFLY HAS BECOME WESTERLY WHICH IS ALLOWING WARM ADVECTION OCCURRING NORTH OF WEAK SFC WARM FRONT OVER SOUTHERN MINNESOTA TO AFFECT FAR WESTERN GREAT LAKES. LOW-LEVELS BLO H85 PER 12Z SOUNDINGS FM GRB/INL/MPX REMAIN QUITE DRY...BUT MOISTURE AND WARM ADVECTION MAINLY AT H7 IS DRIVING AREA OF SCT LIGHT SHOWERS OVER NORTHWEST WI. EVEN SOME SNOW WAS REPORTED IN NORTHEAST MINNESOTA EARLIER TODAY AS TEMPS WERE IN THE 30S AS THE PRECIP BEGAN. BASED ON WHERE RAP/NAM SHOW NOSE OF H7 MOISTURE TRANSPORT INTO THIS EVENING...SOME OF THE SHRA OVER NORTHWEST WI MAY CLIP SW UPR MICHIGAN THROUGH MIDNIGHT. GREATEST CHANCES FM IRONWOOD TO IRON RIVER. WEAK FORCING ALOFT AND PERSISTENT DRY LOW-LEVELS WILL PROHIBIT THE PRECIP FM MAKING IT VERY FAR TO THE NORTH AND EAST OF THOSE AREAS. LATEST HRRR MODEL RUNS ARE PICKING UP ON THIS...SHOWING ANY SIMULATED REFLECTIVITY AT 1KM OF NOTE FADING AS IT MOVES INTO SCNTRL UPR MICHIGAN. AS TEMPS COOL ENOUGH IN BLYR AFTER SUNSET...MAY SEE RAIN TRY TO TURN TO SNOW BRIEFLY BEFORE THE WANING FORCING ALLOWS THIS PRECIP TO END. NOT EXPECTING ANYTHING MORE THAN A COATING OF SNOW ACCUMULATION IF IT OCCURS AT ALL. TEMPS TONIGHT WILL BE COOLEST IN THE EAST /UPR TEENS TO LOW 20S/ CLOSER TO SFC HIGH AND WHERE SKIES STAY MOSTLY CLEAR. ELSEWHERE EXPECT READINGS IN UPR 20S TO MID 30S...WARMEST WEST. MID CLOUDS GRADUALLY FADE AWAY ON SATURDAY AS SFC HIGH PRESSURE BUILDS IN FM HUDSON BAY. NORTHERLY GRADIENT WINDS TIED INTO THE HIGH WILL KEEP AREAS NEAR LK SUPERIOR SHORE STUCK IN THE 30S DESPITE THE INCREASING SUNSHINE. WARMEST TEMPS INTO THE LOW 50S WILL BE ALONG WI BORDER AND ALSO NEAR LK MICHIGAN WITH NORTH WINDS COMING OFF THE LAND OF EAST HALF OF UPR MICHIGAN. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 449 AM EDT FRI APR 24 2015 AFTER A FEW PERIODS OF MUCH NEEDED PCPN DURING THE LAST 2 WEEKS...THE PATTERN IS ONCE AGAIN BECOMING ONE THAT FAVORS DRY WEATHER IN THE UPPER GREAT LAKES. RIDGING/POSITIVE HEIGHT ANOMALIES DEVELOPING FROM THE UPPER MISSISSIPPI VALLEY THROUGH HUDSON BAY THIS WEEKEND WILL REDEVELOP W TO THE ROCKIES NEXT WEEK. THIS CHANGE IN THE UPPER LEVELS WILL TRANSLATE TO SFC HIGH PRES RIDGING S FROM HUDSON BAY THIS WEEKEND AND THEN HIGH PRES SETTLING S THRU THE PLAINS TO THE WRN GULF THRU THU NEXT WEEK. END RESULT IS AN OVERALL DRY PATTERN WITH NO CHANCE FOR GULF MOISTURE TO REACH UPPER MI DURING THE LONG TERM PORTION OF THE FCST. AS FOR TEMPS...SFC HIGH PRES RIDGING S FROM HUDSON BAY THIS WEEKEND WILL KEEP TEMPS BLO NORMAL...ESPECIALLY ACROSS THE N WHERE GRADIENT WINDS REMAIN OFF LAKE SUPERIOR. GRADUAL WARMING WILL OCCUR NEXT WEEK...AND THIS WILL LEAD TO TEMPS RISING TO ABOVE NORMAL FOR ALL OR MOST LOCATIONS BY WED/THU. HOWEVER...00Z MODEL RUNS CAST DOUBT ON THE WARMTH MIDWEEK. MORE ON THAT LATER. OVER THE WEEKEND...AFORMENTIONED SFC HIGH PRES RIDGING S FROM HUDSON BAY INTO THE UPPER LAKES WILL KEEP CONDITIONS NEAR LAKE SUPERIOR ON THE CHILLY SIDE WITH HIGH TEMPS NOT GETTING HIGHER THAN THE LOWER 40S AT BEST. SOME LAKESIDE LOCATIONS FROM THE KEWEENAW EASTWARD WON`T GET OUT OF THE 30S ON BOTH DAYS. WELL IN THE INTERIOR... ESTIMATED MIXING HEIGHTS ON NAM/GFS FCST SOUNDINGS SUGGEST HIGHS SAT/SUN AROUND 50F TO THE LWR 50S. SUN MAY END UP SLIGHTLY COOLER THAN SAT AT MANY LOCATIONS UNDER A MORE NORTHERLY WIND AS OPPOSED TO THE MORE NORTHEASTERLY WIND ON SAT. WHILE CLOUDS WILL BE DECREASING OVER THE W SAT...LEADING TO MOSTLY SUNNY CONDITIONS ACROSS THE AREA IN THE AFTN...SOME MOISTURE MAY BACK IN FROM THE NE FOR SUN... LEADING TO A LITTLE MORE CLOUD COVER AT THAT TIME. MIN TEMPS SAT NIGHT AND SUN NIGHT WILL BE IN THE 20S IN THE INTERIOR. SFC HIGH WILL CONTINUE TO RIDGE S INTO UPPER MI ON MON...SO MON WILL BE SIMILAR TO SUN. HOWEVER...WITH WEAKENING PRES GRADIENT AND SLIGHT MODERATION OF AIR MASS...MAX TEMPS MON SHOULD BE SEVERAL DEGREES HIGHER THAN SUN...ESPECIALLY IN THE INTERIOR. MEDIUM RANGE MODELS INDICATE A SHORTWAVE MOVING ACROSS THE NRN PLAINS MON NIGHT. AS MID/UPPER RIDGE BEGINS BUILDING OVER THE ROCKIES...THIS WAVE MAY END UP DIVING SE OR S TOWARD A SRN TROF OVER TX/LWR MISSISSIPPI VALLEY REGION PER 12Z ECMWF AND 00Z/12Z GEM... RESULTING IN CONTINUED DRY WEATHER HERE. EVEN IF THE GFS WHICH DRIVES SHORTWAVE THRU THE UPPER LAKES IS CORRECT...LACK OF MOISTURE ADVECTION/ANTECEDANT DRY AIR MASS SUGGEST VERY LITTLE POTENTIAL OF ANY PCPN. 00Z ECMWF HAS TRENDED STRONGER WITH A MORE EASTWARD PROGRESSION OF SHORTWAVE BEFORE DIVING SE...RESULTING IN POTENTIAL OF SHRA SPREADING INTO UPPER MI TUE AFTN AND NIGHT. WITH THIS THE FIRST RUN TRENDING IN THAT DIRECTION...WILL MAINTAIN A DRY FCST FOR NOW. HEADING INTO WED/THU...GENERAL TREND OF 00Z MEDIUM RANGE GUIDANCE IS FOR UPSTREAM RIDGING TO BE A BIT MORE PRONOUNCED...RESULTING IN SHARPER NW FLOW DEVELOPING INTO THE UPPER LAKES. SINCE THIS HAS OFTEN BEEN A FAVORED PATTERN OVER THE LAST FEW MONTHS...THIS TREND IN THE 00Z MODEL RUNS MAY END UP BEING A CORRECT TREND. THIS SUGGESTS THE WARMTH (TEMPS NEAR TO SLIGHTLY ABOVE NORMAL) REFLECTED IN THE FCST FOR WED/THU (A RESULT OF MORE WEIGHTING FROM THE PREVIOUS WARMER SOLUTIONS) MAY BE TOO OPTIMISTIC. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 119 PM EDT FRI APR 24 2015 HIGH PRESSURE AND DRY CONDITIONS SHOULD REMAIN IN CONTROL OF ALL 3 TAF SITES THROUGH THE PERIOD...WITH VFR CEILINGS/VIS. THE ONLY SMALL EXCEPTION WILL BE IWD LATE THIS AFTN INTO EARLY THIS EVENING...WHERE SOME LIGHT SHRA MAY DROP CONDITIONS TO MVFR. WINDS WILL BE LIGHT INTO SATURDAY. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 241 PM EDT FRI APR 24 2015 HIGH PRESSURE WILL BE THE DOMINANT WEATHER FACTOR OVER THE UPPER GREAT LAKES THIS WEEKEND AND THROUGH MUCH OF NEXT WEEK. OVERALL THE WINDS WILL STAY AT OR BLO 20 KTS. THE ONE MAIN EXCEPTION WILL BE TONIGHT AND SATURDAY OVER WESTERN LK SUPERIOR WHERE EAST TO NORTHEAST WINDS OF 20-25 KTS WITH GUSTS TO AROUND 30 KTS ARE EXPECTED AS STRONGER HIGH PRESSURE AREA INITIALLY BUILDS OVER THE REGION. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...ROLFSON AVIATION...JLA MARINE...JLA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
606 AM CDT FRI APR 24 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 348 AM CDT FRI APR 24 2015 STRONG THETA-E ADVECTION IS ENSUING ACROSS THE AREA...WITH SKIES MAINLY CLOUDY NOW ACROSS MN AS A RESULT. AS STRONG AS THIS FORCING MAY BE...IT IS RUNNING INTO ONE HUGE PROBLEM...THE INCREDIBLY DRY AIRMASS IN THE LOWER LEVELS IN PLACE ACROSS THE AREA EARLY THIS MORNING. EVEN AT 3 AM THERE WERE SEVERAL LOCATIONS THAT STILL HAD HUMIDITIES UNDER 25 PERCENT AND IN FACT...THERE ARE A FEW SITES OUT IN WRN MN THAT ARE EVEN BORDERLINE RED FLAG CRITERIA WHERE SE WINDS ARE STARTING TO GUST OUT OVER 20 MPH WITH HUMIDITIES UNDER 30 PERCENT. THE TRUE MAGNITUDE OF HOW DRY THIS AIRMASS IS COMES FROM THE TWO SOUNDINGS RELEASED FROM MPX ON THURSDAY...BOTH OF WHICH TALLIED PWATS UNDER A TENTH OF AN INCH. THIS IS COMMON WITH ARCTIC OUTBREAKS IN THE DEAD OF WINTER...BUT IT IS EXCEEDINGLY RARE TO SEE PWATS SO LOW AT THIS POINT IN APRIL. WITHIN THIS WARM ADVECTION...THE MOISTURE CONVERGENCE AND FRONTOGENESIS ARE REALLY CENTERED AROUND SE NODAK...WHERE RAIN IS FINALLY STARTING TO MAKE INROADS TO THE SFC UP AROUND FARGO. FOR THE REST OF TODAY...THEIR IS QUITE A BIT OF SPREAD AMONGST THE SHORT TERM MODELS ON HOW THIS SYSTEM WILL SPREAD RAINFALL INTO AREA...SO THERE IS LOW CONFIDENCE ON EXACT TIMING OF PRECIP AT ANY ONE LOCATION. THIS IS LIKELY DUE TO THE LACK OF MUCH JET SUPPORT...ALONG WITH NO REAL SHORT WAVE TO HELP FOCUS ACTIVITY. INSTEAD...TODAY LOOKS TO BRING A GOOD 6-10 HOUR WINDOW TO MOST LOCATIONS WHERE LIGHT RAIN WILL BE INTERMITTENT AS THE ZONE OF THETA-E ADVECTION SWINGS THROUGH. DID CUT BACK SOME MORE ON QPF AS WELL...WITH THIS LOOKING TO BE YET ANOTHER DISAPPOINTING SYSTEM IN THE RAINFALL DEPARTMENT...WITH MOST FOLKS GETTING UNDER A TENTH OF AN INCH OF RAIN. THE ONLY AREA THAT LOOKS LIKE THEY COULD DO BETTER THAN THAT IS ACROSS CENTRAL MN...AS FRONTAL FORCING CURRENTLY IN THE FARGO AREA PUSHES EAST THIS MORNING BEFORE WEAKENING. FOR THE WEATHER GRIDS...MADE TWO CHANGES. ONE WAS TO INTRODUCE ISOLATED THUNDER WORDING AS THE PLUME OF INSTABILITY CURRENTLY UP INTO SE SODAK WILL PUSH INTO SW MN THIS AFTERNOON...WITH THE NAM SHOWING A FEW HUNDRED J/KG OF MUCAPE WORKING UP TO ABOUT A RED WING TO ALEXANDRIA LINE. ADDING FURTHER SUPPORT TO BRINGING IN THE THUNDER MENTION WERE THE FACT THAT WE HAVE SEEN INTERMITTENT LIGHTNING ACTIVITY ALL NIGHT WITH THE SHOWERS WORKING ACROSS THE DAKOTAS...WITH THE SPC SREF THUNDERSTORM PROBABILITIES GETTING UP ABOUT AS FAR NORTH AS I-94 AS WELL. THE SECOND CHANGE WAS TO REMOVE ANY MIXED PRECIP FROM THE GRIDS THIS MORNING AS CLOUD COVER OVERNIGHT KEPT TEMPERATURES HIGHER THAN WERE FORECAST...MEANING PRECIP MOVING IN WILL HAVE NO PROBLEM MAINTAINING A LIQUID STATE. TONIGHT WHAT LOOKS LIKE A CERTAINTY IS THE DEVELOPMENT OF LOW STRATUS. AGAIN...THE FORCING FOR PRECIP DOES NOT LOOK ALL THAT GREAT AS SFC ENERGY CONSOLIDATES INTO A SUB 1000 MB LOW THAT WILL BE MOVING INTO THE KC AREA. THIS LOOKS TO KEEP THE BULK OF THE PRECIP SOUTH OF THE MPX AREA...WITH THIS AREA LOOKING TO GET MORE LIGHT RAIN/SPRINKLES TO GO ALONG WITH THE STRATUS. BASED ON WHAT WE SAW WITH TEMPERATURES WITH THE CLOUDS TONIGHT...DID BOOST LOWS TONIGHT A FEW DEGREES WITH THE CLOUDY SKIES EXPECTED. THIS RESULTED IN THE BULK OF THE MIXED IN THE FORECAST FOR TONIGHT GETTING REMOVED AS WELL. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 348 AM CDT FRI APR 24 2015 GOOD CONTINUITY CONTINUES BETWEEN THE GFS AND ECMWF FOR MUCH OF THE LONG TERM...LEADING TO HIGHER CONFIDENCE WITH THE SENSIBLE WEATHER. RAIN WILL DIMINISH FROM NORTH TO SOUTH ON SATURDAY AS A WAVE OF LOW PRESSURE DROPS SOUTHEAST ACROSS THE MIDDLE MISSISSIPPI VALLEY. LIKELY TO CATEGORICAL POPS CONTINUE IN FAR SOUTHERN MN FOR THE MORNING WITH CHANCE POPS IN THE AFTERNOON. A RIDGE OF HIGH PRESSURE WILL BUILD OVER THE LOCAL AREA FOR SUNDAY AND MONDAY WITH SOME FINE SPRING WEATHER OCCURRING. AFTER HIGHS IN THE LOWER 50S ON SATURDAY...TEMPERATURES WILL WARM TO AROUND 60 FOR SUNDAY WITH LOWER TO MIDDLE 60S FOR TUESDAY...WHICH IS ACTUALLY NORMAL FOR LATE APRIL. THERE REMAINS A SHORT WAVE AND WEAK COOL FRONT THAT WILL PUSH ACROSS THE FORECAST AREA FROM MONDAY NIGHT THROUGH TUESDAY NIGHT. THIS SYSTEM IS WEAKENING WITH TIME WITH ONLY SMALL POPS INDICATED TO THE WEST AND NORTH OF THE TWIN CITIES FOR MONDAY NIGHT AND TUESDAY. A MUCH LARGER RIDGE OF HIGH PRESSURE WILL FOLLOW AND EXPAND OUT ACROSS THE NORTHERN ROCKIES AND PLAINS FOR WEDNESDAY AND THURSDAY. DRY WEATHER IS IN STORE FOR THE REGION WITH HIGH TEMPERATURES TRENDING ABOVE NORMAL WITH UPPER 60S TO LOWER 70S LIKELY. EVEN WARMER TEMPERATURES ARE POSSIBLE FOR THE END OF THE WEEK (FRIDAY AND SATURDAY) AS RIDGING ALOFT DOMINATES THE CENTRAL THIRD OF THE CONUS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 606 AM CDT FRI APR 24 2015 LLJ WORKING INTO WRN MN THIS MORNING HAS SHOWERS WITH EMBEDDED TSTRMS FROM OMAHA TO FARGO. HOWEVER...WE ARE STILL DEALING WITH A VERY DRY AIRMASS IN THE LOW LEVELS WHICH IS MAKING EWRD PROGRESS INTO THE MPX AREA DIFFICULT. FELT TIMING FROM INHERITED TAFS LOOKED GOOD BASED ON LATEST HRRR/HOPWRF FORECASTS SO MADE MINIMAL CHANGES THERE. GIVEN THE DRY AIR...ALSO FAVORED THE SLOWER SREF FOR BRINGING MVFR AND LOWER CIGS INTO THE AREA. IN FACT...SREF CIG PROBABILITIES PAINT THE POSSIBILITY THAT DRY ERLY FLOW WILL KEEP THE WI TERMINALS VFR THROUGH THIS TAF PERIOD. AT THE VERY LEAST...LOWEST CLOUDS LOOK TO BE OUT IN WRN MN TONIGHT...WITH IFR OR LOWER CIGS LIKELY WEST OF I-35. KMSP...UNCERTAINTY EXISTS ON TWO FRONT FOR THIS TAF...TIMING ON WHEN OR EVEN IF MSP SEES RAIN ALONG WITH HOW LOW DO CIGS GO. FOR THE RAIN...ONE BAND OF VIRGA ALREADY MOVED THROUGH THIS MORNING...BUT MAIN BATCH OF FORCING LOOKS TO ARRIVE CLOSER TO 18Z. FOR MUCH OF THE AFTERNOON...EXPECT INTERMITTENT PERIODS OF -RA THAT MAY CONTINUE INTO MUCH OF TONIGHT. HRRR AND LAMP WOULD SAY MVFR CIGS MOVE IN WITH THE RAIN CHANCES...BUT GIVEN HOW DRY WE ARE IN THE LOW LEVELS...FAVORED THE SLOWER TIMING OF THE SREF. CONFIDENCE ON CIGS GOING BELOW 018 TONIGHT IS MEDIUM AS LOWER CIGS AND BETTER MOISTURE LOOK TO REMAIN OFF TO THE WEST...WITH CONTINUED DRY ERLY SFC WINDS PLAYING HAVOC ON CLOUD HEIGHTS THROUGH TONIGHT. /OUTLOOK FOR KMSP/ SAT...BCMG VFR. WINDS E 10-15 KT. SUN...VFR. WINDS NE 5-10 KT. MON...VFR. WINDS NNE 5 KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...RAH AVIATION...MPG
AREA FORECAST DISCUSSION
NWS JACKSON MS
445 PM CDT FRI APR 24 2015 .DISCUSSION...MORNING CONVECTIVE COMPLEXES HAVE DIMINISHED AS THEY HAVE MOVED EAST BUT HAVE BROUGHT SOME RAIN TO THE REGION THROUGH THIS AFTERNOON. ADDITIONAL SHOWERS AND A FEW THUNDERSTORMS CONTINUE TO MOVE INTO THE REGION FROM THE WEST BUT THESE ARE MUCH MORE SCATTERED. DESPITE THE DRIER AIR THAT WAS IN PLACE ACROSS THE REGION THIS MORNING...LOW LEVEL MOISTURE HAS RETURNED TO THE REGION WITH DEWPOINTS ACROSS SOUTHERN AND CENTRAL SECTIONS OF THE REGION IN THE MID TO UPPER 60S. THIS IS THANKS TO A NORTHWARD MOVING WARM FRONT FROM THE COAST. NORTH OF THE WARM FRONT...DEWPOINTS ARE IN THE MID 50S BUT EXPECT THAT THESE SHOULD INCREASE THROUGH THE REMAINDER OF THE EVENING AS SOME MODELS EVEN SHOW UP TO 70 DEGREE DEWPOINTS ACROSS PORTIONS OF THE REGION. MODELS CONTINUE TO INDICATE THAT ADDITIONAL STORMS WILL DEVELOP ACROSS THE DELTA AS THE EVENING PROGRESSES....PARTICULARLY AFTER 8-10PM. AT THIS POINT VERTICAL TOTALS AND DEEP LAYER SHEAR INCREASE THROUGH THE EVENING(WITH SHEAR VALUES APPROACHING 60-70KTS) AND SHOULD BE PLENTY SUFFICIENT FOR DAMAGING WINDS...HAIL AND TORNADOES. IT APPEARS THAT THE LATEST RUNS OF THE HRRR MIGHT HAVE THE BEST HANDLE ON THE SITUATION AS A SMALL AREA OF LOW PRESSURE DEVELOPS IN THE DELTA IN ASSOCIATION WITH THE APPROACHING SQUALL LINE. IT BRINGS THE LINE THROUGH MOSTLY THE NORTHERN SECTIONS OF MY CWA FROM ABOUT 03-10Z WITH SEVERAL LEWP STRUCTURES AND IT DOES APPEAR THAT LOCATIONS ALONG AND NORTH OF I-20 HAVE THE GREATEST SEVERE POTENTIAL...ESPECIALLY IN THE DELTA. WE HAVE GONE AHEAD AND UPGRADED OUR HWO PRODUCTS ESPECIALLY IN THE DELTA WHERE A SIGNIFICANT THREAT FOR SEVERE WEATHER IS EXPECTED WITH GREATER THAN 75MPH WINDS AND STRONG TORNADOES POSSIBLE. /28/ ON SATURDAY THE OVERNIGHT THUNDERSTORM ACTIVITY WILL LEAVE A BOUNDARY SET UP OVER THE AREA AND THE GFS/ECMWF INDICATE AT LEAST ISOLATED TO SCATTERED THUNDERSTORM POTENTIAL SATURDAY AFTERNOON. WITH GOOD LAPSE RATES OF AROUND 6.5 C/KM...LARGE HAIL LOOKS LIKE IT WILL BE THE MAIN CONCERN ALONG WITH DAMAGING WIND GUSTS. STILL CANT COMPLETELY RULE OUT A TORNADO BUT HAIL AND WIND SHOULD BE THE MAIN CONCERN. EXPECT ALL OF THE THUNDERSTORM POTENTIAL TO END EARLY SATURDAY EVENING WITH CLEARING SKIES SATURDAY NIGHT AS DRIER AIR BUILDS IN./15/ THE UPPER LEVEL PATTERN ACROSS THE CONUS LOOKS TO GET QUITE AMPLIFIED BY SUNDAY AS THE PREVIOUS TROUGH ENERGY BRINGING INCLEMENT WEATHER IN THE SHORT TERM BECOMES PART OF A CONSOLIDATED AND LARGE UPPER LOW OFF THE NORTHEAST COAST AND MORE ENERGY DIGS TOWARD THE SOUTHERN PLAINS. SHORT WAVE RIDGING IN BETWEEN THESE TROUGHS WILL BE OVER THE LOWER MS VALLEY WITH A COLD FRONT PREVIOUSLY EXPECTED TO COME INTO THE NORTH SUNDAY LIKELY DELAYED UNTIL LATE IN THE DAY ACCORDING TO LATEST MODEL CONSENSUS. THIS SHOULD SPELL A VERY WARM AND MOSTLY SUNNY SUNDAY FOR MUCH OF THE REGION WITH HIGHS IN THE MID TO UPPER 80S. BY LATER SUNDAY NIGHT AND ESPECIALLY MONDAY DISTURBANCES SHOULD START EJECTING OUT OF THE APPROACHING PLAINS UPPER LOW...UNDERCUTTING HIGH LATITUDE BLOCKING IN THE PERSISTENTLY ACTIVE SOUTHERN BRANCH OF THE JET STREAM. LATEST MODEL SOLUTIONS ARE HINTING IN THIS PATTERN THAT BAROCLINICITY AND INSTABILITY FOCUSED FROM THE RED RIVER VALLEY TOWARD THE GULF COAST WILL PROVIDE A FOCUS FOR THUNDERSTORM COMPLEXES RIDING SOUTHEAST AND BLENDED GUIDANCE IS CATCHING ON TO THIS. MONDAY AND MONDAY NIGHT POPS ARE MOST STRONGLY FOCUSED IN SOUTHERN (AND ESPECIALLY SOUTHWESTERN) ZONES AND IT IS QUITE POSSIBLE POPS COULD TREND EVEN MORE WEIGHTED TOWARD THE COAST. IT IS NOT UNTIL TUESDAY OR WEDNESDAY WHEN THE UPPER LOW SHOULD COME OVER THE REGION AND POSITIVELY FORCE SOLID RAIN AND EMBEDDED STORM OPPORTUNITIES ACROSS THE WHOLE OF THE LOWER MS VALLEY. MUCH DRIER WEATHER LOOKS TO MOVE IN FOR MIDDLE OF THE WEEK INTO THE WEEKEND AS UPPER RIDGING TAKES HOLD ONCE AGAIN. /BB/ && .AVIATION...AS A WARM FRONT PUSHES NORTHEAST ACROSS THE AREA LATER TONIGHT...EXPECT INCREASING CHANCES FOR TSRA AND LOWER CIGS...ESPECIALLY ALONG AND NORTHWEST OF THE HEZ-JAN-GTR CORRIDOR IN THE 03Z-12Z TIME FRAME. DRIER AIR WILL BECOME TO MOVE BACK IN SATURDAY FROM THE WEST...BUT THERE WILL BE LINGERING CHANCES FOR TSRA ESPECIALLY IN THE HBG/PIB AREA. OTHERWISE...EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE AFTERNOON INTO THE EVENING HOURS. /EC/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 70 85 67 87 / 71 40 8 7 MERIDIAN 68 84 66 86 / 66 50 11 7 VICKSBURG 70 87 66 87 / 74 26 8 9 HATTIESBURG 71 85 68 89 / 42 45 10 8 NATCHEZ 71 85 68 86 / 53 31 7 7 GREENVILLE 67 86 63 82 / 97 22 5 9 GREENWOOD 67 86 63 83 / 96 34 8 10 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ 28/15/BB/EC
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
905 PM MDT SAT APR 25 2015 .UPDATE... LOWER POPS ACROSS THE CENTRAL ZONES TONIGHT. MODELS AND RADAR DO NOT SHOW MUCH OF ANYTHING OUTSIDE OF THE MOUNTAINS UNTIL THE EARLY MORNING HOURS. THERE SHOULD BE SUFFICIENT CLOUD COVER TO KEEP ANY FOG FROM FORMING FROM MILES CITY EAST. SREF PROBABILITIES ARE NOT VERY HIGH FOR FOG AND HRRR IS NOT SHOWING MUCH EITHER...SO HAVE NOT ADDED ANY FOR TO THE FORECAST. REIMER && .SHORT TERM...VALID FOR SUN AND MON... UPPER TROUGH AND DISTURBANCE THAT BROUGHT THE RAIN AND RAIN/SNOW MIX OVERNIGHT TO OUR CENTRAL AND WESTERN AREAS OVERNIGHT AND THIS MORNING WILL CONTINUE TO SHIFT NORTH AND EAST FOR THE REMAINDER OF THIS AFTERNOON. AREA OF LIGHT RAIN HAS MOSTLY MOVED INTO ROSEBUD COUNTY WITH MOVEMENT MAINLY NORTHWARD. HAVE SHIFTED LIKELY POPS FROM OUR CENTRAL AREAS TO OUR FAR EASTERN AREAS FOR THIS EVENING AND KEPT A HIGH SCATTERED SHOWER CHANCE ELSEWHERE AS RADAR IS SHOWING SOME SHOWER ACTIVITY MOVING OFF THE BEARTOOTH FOOTHILLS. AREAS FROM BIG HORN COUNTY TO YELLOWSTONE AND WHEATLAND COUNTIES WILL SEE A BREAK IN THE SHOWERS THIS AFTERNOON AS THE ACTIVITY WILL BE MORE ISOLATED IN NATURE. HOWEVER...THIS WILL BE SHORT- LIVED AS THE NEXT SYSTEM WILL QUICKLY MOVES INTO THE AREA TONIGHT. A LARGE TROUGH AND UPPER LOW CURRENTLY MOVING ONTO THE PACIFIC NORTHWEST COAST WILL INTO THE CENTRAL AND NORTHERN ROCKIES LATE TONIGHT AND SUNDAY. THE STRONGEST DYNAMICS STILL LOOK TO REMAIN TO OUR SOUTH BUT NOT AS FAR SOUTH AS THE PAST COUPLE OF DAYS HAVE INDICATED. MODELS KEEP THE BULK OF THE HEAVIEST PRECIP ACROSS WYOMING BUT LATEST MODELS SHIFT SOME OF THIS FURTHER NORTH ACROSS OUR FAR SOUTHERN AREAS. WILL STILL CONTINUE TO BRING IN LIKELY POPS LATE THIS EVENING THROUGH SUNDAY MORNING ACROSS ALL BUT THE FAR NORTHERN PORTIONS OF OUR FORECAST AREA. THE STRONGEST DYNAMICS AND ASSOCIATED COOLING STILL LOOK TO STAY TO OUR SOUTH BUT MODELS DO BRING A BIT MORE COLDER AIR INTO THE MOUNTAIN AND FOOTHILLS LOCATIONS. THIS WILL RESULT IN THE POSSIBILITY OF SOME SNOW FOR THE RED LODGE AREA LATE TONIGHT INTO SUNDAY MORNING WITH THE POSSIBILITY OF AN INCH OR TWO OF ACCUMULATION WITH A COLD RAIN FURTHER EAST ACROSS THE ADJACENT PLAINS. LIKELY POPS WILL CONTINUE ALL DAY SUNDAY WITH THE PRECIP SLOWLY SHIFTING EAST INTO THE DAKOTAS BY EVENING LEAVING JUST A CHANCE FOR SHOWERS ACROSS THE AREA. THE EXCEPTION WILL BE OUT TOWARD THE DAKOTA BORDERS WHERE LIKELY POPS WILL CONTINUE THROUGH SUNDAY NIGHT. WE MAY SEE AROUND 4 TO 7 INCHES OF SNOW ACCUMULATION FOR THE HIGHER ELEVATIONS OF THE BEARTOOTH/ABSAROKA AND BIG HORN MOUNTAINS FROM TONIGHT INTO MONDAY MORNING. CONDITIONS BEGIN TO DRY OUT BY MONDAY AS HIGH PRESSURE RIDGING BEGINS TO BUILD ACROSS THE NORTHERN ROCKIES. TEMPERATURES SUNDAY WILL BE QUITE CHILLY ESPECIALLY COMBINED WITH THE SHOWERS AND RAIN WITH READINGS ONLY IN THE LOWER TO MIDDLE 50S. HOWEVER...TEMPERATURES AROUND NORMAL WILL RETURN FOR MONDAY WITH LOWER 60S COMMON. HOOLEY .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... LITTLE IN THE WAY OF CHANGES AGAIN FOR EXTENDED FORECAST PERIOD. MODELS REMAIN IN PRETTY GOOD AGREEMENT THROUGHOUT. THERE ARE A FEW TIMING ISSUES LATE IN THE PERIOD... BUT IS TO BE EXPECTED...AS SOUTHWEST FLOW SETS UP AND MULTIPLE SHORTWAVES CROSS THING THE REGION. A STRONG UPPER LEVEL RIDGE WILL DOMINATE THE PATTERN TO BEGIN THE PERIOD...BRINGING SUNNY AND DRY CONDITIONS TO THE REGION. TEMPS WILL CLIMB INTO THE MID 70S TUESDAY AND AROUND 80 IN MOST LOCATIONS ON WEDNESDAY. RIDGING GIVES WAY TO SOUTHWEST FLOW ALOFT ON WEDNESDAY NIGHT...AS A DEEP TROF DEVELOPS ALONG THE WEST COAST. THIS PATTERN WILL PERSISTS THROUGH THE END OF THE EXTENDED PERIOD...BRINGING PACIFIC MOISTURE AND MULTIPLE SHORTWAVES ACROSS THE REGION. NOTHING APPEARS SIGNIFICANTLY STRONG TO HANG OUR HAT ON AT THIS POINT...BUT SHOWERS WILL BE A POSSIBILITY THROUGHOUT THE LAST HALF OF THE PERIOD. CLOUD COVER AND SHOWERS SHOULD KEEP TEMPS A BIT COOLER...BUT STILL IN 70S ACROSS THE REGION. AAG && .AVIATION... A FEW SHOWERS ARE POSSIBLE W OF KBIL THROUGH 06Z...OTHERWISE RAIN AND SNOW SHOWERS WILL MOVE INTO THE WESTERN MOUNTAINS AND FOOTHILLS OVERNIGHT...AS WELL AS INTO THE NE BIGHORNS. RAIN SHOWERS WILL OVERSPREAD THE ENTIRE AREA ON SUN WITH RAIN AND SNOW SHOWERS OVER AND NEAR THE FOOTHILLS. EXPECT MVFR/IFR CONDITIONS WITH THE PRECIPITATION TONIGHT AND SUN. MOUNTAIN OBSCURATIONS WILL INCREASE TONIGHT AND BE WIDESPREAD ON SUN. ARTHUR && .PRELIMINARY POINT TEMP/POPS... SUN MON TUE WED THU FRI SAT ----------------------------------------------------------- BIL 038/052 037/062 041/076 048/080 048/073 049/075 048/070 36/R 31/B 00/U 01/U 12/W 22/W 22/W LVM 035/050 030/062 035/073 044/076 043/069 042/070 041/062 67/R 31/B 00/U 01/U 13/W 22/W 22/W HDN 037/056 037/064 039/076 047/081 048/075 050/078 049/071 26/R 41/B 00/U 00/U 12/W 22/W 22/W MLS 037/056 038/064 040/075 047/081 049/075 051/078 050/071 24/R 41/B 00/U 00/U 11/U 22/W 22/W 4BQ 037/052 038/060 037/072 045/079 047/076 048/078 050/072 38/R 72/W 00/U 00/U 02/W 22/W 22/W BHK 036/053 037/057 038/070 044/075 046/072 048/076 050/070 37/R 83/W 00/U 00/U 11/U 22/W 22/W SHR 037/049 034/060 037/071 042/075 045/072 046/074 046/068 47/R 62/W 00/U 00/U 11/U 22/W 22/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
250 PM CDT FRI APR 24 2015 .SHORT TERM...(TONIGHT THROUGH MONDAY) ISSUED AT 250 PM CDT FRI APR 24 2015 THE PRIMARY FORECAST CONCERNS IN THE SHORT TERM ARE POTENTIAL FOR SEVERE STORMS...MAINLY BEFORE 08Z...AND THEN RAIN CHANCES LINGERING ON SATURDAY. SOME AREAS OF HEAVY RAIN ARE POSSIBLE TONIGHT. SURFACE ANALYSIS AT MID AFTERNOON SHOWED TWO LOW PRESSURE CENTERS. ONE WAS OVER WESTERN KANSAS AND THE OTHER WAS OVER CENTRAL SOUTH DAKOTA. THE FIRST LOW WILL STRENGTHEN OVERNIGHT AND TRACK INTO NORTHWEST MISSOURI BY DAYBREAK SATURDAY. MODEST LOW LEVEL MOISTURE HAD MOVED NORTHWARD INTO THE FORECAST AREA WITH DEWPOINTS IN THE LOWER TO MID 50S AT MANY LOCATIONS. LATEST SPC MESOSCALE ANALYSIS SHOWED THE MIXED LAYER CAPE AXIS EXTENDING FROM CENTRAL KANSAS TO SOUTHWEST NEBRASKA THEN INTO NORTH CENTRAL NEBRASKA. EFFECTIVE SHEAR VALUES AS OF 19Z WERE MOSTLY LESS THAN 30 KNOTS LOCALLY. MID LEVEL LAPSE RATES WERE MOSTLY 7.5 TO 8.5 DEGREES C PER KM. EXPECT THAT STORMS WILL INCREASE IN COVERAGE TO OUR WEST AND SOUTH LATER THIS AFTERNOON AND EVENING...THEN CONTINUE FOR THE OVERNIGHT. RECENT HRRR AND RAP MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THAT. SEVERE THREAT APPEARS TO BE MAINLY HAIL AND THAT MAINLY IN OUR FAR SOUTHWEST COUNTIES AS STORMS LIFT/MOVE NORTHEAST FROM KANSAS. THERE IS ALSO SOME THREAT OF HAIL WITH STORMS THAT MAY AFFECT PARTS OF NORTHEAST NEBRASKA MAINLY BEFORE MIDNIGHT. HIGHEST POTENTIAL FOR PCPN AMOUNTS OF AN INCH OR MORE IS ACROSS SOUTHEAST NEBRASKA AND SOUTHWEST IOWA...BUT ALL AREAS COULD SEE LOCALLY HEAVY RAIN. ON SATURDAY...PCPN SHOULD DECREASE IN COVERAGE AND INTENSITY DURING THE MORNING. SOME LIGHT SHOWERS COULD LINGER INTO THE AFTERNOON... MAINLY IN SOUTHWEST IOWA. OTHERWISE...A WEAK RIDGE OF HIGH PRESSURE WILL BUILD INTO THE FORECAST AREA WITH NORTHERLY WINDS. CLOUDS ARE EXPECTED TO LIMIT HEATING...SO KEPT MOST HIGHS SATURDAY IN THE MID 50S TO LOWER 60S. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 250 PM CDT FRI APR 24 2015 THIS PERIOD SHOULD BE MAINLY DRY WITH MODERATING TEMPERATURES. A CLOSED LOW AT 500 MB IS EXPECTED TO BE OVER THE TEXAS PANHANDLE AT THE START OF THIS PERIOD. THIS WILL TRACK OFF TO THE NORTHEAST AND OPEN UP THROUGH MID WEEK AS A RIDGE BUILDS IN FROM THE NORTHWEST. THE EARLY PART OF THE WEEK MAY NOT BE COMPLETELY DRY...BUT AT THIS TIME PCPN CHANCES SEEMED TO BE 14 PERCENT OR LESS FOR ANY GIVEN PERIOD. HIGHS WILL START OUT IN THE 60S MONDAY/TUESDAY...THEN WARM TO THE 70S BY THURSDAY AND POSSIBLY NEAR 80 BY FRIDAY. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1217 PM CDT FRI APR 24 2015 MVFR CIGS WILL CONT THROUGH THE AFTN AT KOMA/KLNK AND WILL MOVE INTO KOFK OVER THE NEXT COUPLE OF HOURS. DRY CONDITIONS ARE EXPECTED THROUGH THE AFTERNOON...BUT RA CHCS WILL INCREASE THIS EVENING FOR ALL 3 TAF SITES. KOFK MAY SEE SOME SHRA MV IN FM THE NW FM TSRA THAT DEVELOP ALONG THE COLD FRONT IN NORTHERN NEB...BUT WILL HOLD OFF WITH THUNDER MENTION FOR NOW THERE. KLNK/KOMA WILL SEE ACTIVITY INCREASE FM THE SOUTH THROUGH THE EVENING AND WILL INCLUDE SOME THUNDER AT KLNK BUT WILL LEAVE OUT OF KOMA ATTM. IFR CONDS ARE LIKELY OVERNIGHT AS THE FRONT MOVS THRU THE SITES... IMPROVING TO MVFR ON SAT MRNG. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1156 PM CDT THU APR 23 2015 .SYNOPSIS... ISSUED AT 320 PM CDT THU APR 23 2015 SPLIT UPPER LEVEL PATTERN OVER THE WESTERN HALF OF THE CONUS...BROAD CYCLONIC FLOW TO THE EAST. A SHORTWAVE RIDGE WAS TRANSLATING EAST ACROSS THE CENTRAL PLAINS...IN ADVANCE OF A STRONG PV MAX SLOWLY MOVING NORTHEASTWARD ACROSS THE DESERT SOUTHWEST. THE ASSOCIATED HEIGHT FALLS WITH THIS PATTERN WERE SUPPORTING THE GRADUAL DEEPENING OF A LEE SIDE SFC TROUGH FROM NORTHEAST COLORADO THROUGH THE WESTERN NEBRASKA PANHANDLE. EAST OF THIS TROUGH WINDS WERE BREEZY OUT OF THE SOUTH...TRANSPORTING LOW LEVEL MOISTURE INTO THE CWA. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 320 PM CDT THU APR 23 2015 CUMULUS CLOUDS AND A FEW SHOWERS AND THUNDERSTORMS HAVE ALREADY DEVELOPED JUST WEST OF THE CWA EARLY THIS AFTERNOON. HI-RES MODELS HAVE CONSISTENTLY SHOWN THE THUNDERSTORM ACTIVITY INCREASING IN COVERAGE AND MOVING EAST LATER THIS AFTERNOON AS A WEAK UPPER LEVEL SHORTWAVE EJECTS OUT OF THE CENTRAL ROCKIES. THE BEST CHANCES THROUGH THE EVENING WILL GENERALLY BE CONFINED TO THE PANHANDLE AND SOUTHWEST NEBRASKA. AS FAR AS STORM INTENSITY...MLCAPE IN THE VICINITY OF THE SFC TROUGH WILL NEAR 1000 J/KG BY LATER AFTERNOON AND EARLY EVENING. STEEP MID LEVEL LAPSE RATES OF 7-8 C/KM ARE ALSO IN PLACE OVER THE HIGH PLAINS. A STORM OR TWO REACHING STRONG TO SEVERE LIMITS WITH HAIL AND GUSTY WINDS CANNOT BE RULED OUT...MAINLY WEST OF HWY 61. THE ABILITY FOR STORMS TO SUSTAIN THEMSELVES AND REMAIN ORGANIZED IS IN QUESTION DUE RATHER WEAK MID LEVEL FLOW AND DEEP LAYER SHEAR ONLY AROUND 25 TO 30 KTS. THE MORE FAVORABLE ENVIRONMENT WILL REMAIN TO THE SOUTH WHERE FASTER FLOW ALOFT AND BETTER SHEAR PROFILES RESIDE. THUNDERSTORM CHANCES MOVE EAST OVERNIGHT BUT COVERAGE SHOULD REMAIN SCATTERED. UPPER LEVEL LOW CURRENTLY OVER THE DESERT SOUTHWEST WILL EJECT EASTWARD TOWARD THE CENTRAL PLAINS. THIS WILL KEEP SOUTHERLY FLOW IN PLACE OVERNIGHT...AND EVENTUALLY THE REDEVELOPMENT OF STRATUS CLOUDS OVER MUCH OF THE AREA. PATCHY FOG IS POSSIBLE OVER CENTRAL NEB...BUT BUFKIT DATA CONTINUES TO SUPPORT THICK LOW STRATUS IN OUR ZONES. THIS IS ALSO SUPPORTED BY VISBY FIELDS IN RECENT RUNS OF THE HRRR AND NAM. CONFIDENCE NOT HIGH ENOUGH TO INCLUDE ANY FOG IN THE GRIDS AT THIS POINT...BUT THE EVENING SHIFT WILL NEED TO REEVALUATE. MODELS PAINT QPF ACROSS MUCH OF THE CWA BY FRIDAY AFTERNOON...BUT REMAIN ALL OVER THE PLACE IN REGARDS TO THEIR PLACEMENT. EXPECTING SCATTERED AND DISORGANIZED SHOWERS AND THUNDERSTORMS DUE TO LACK OF A FOCUS FOR DEVELOPMENT. NOT EXPECTING MUCH IN THE WAY OF SEVERE WEATHER AS THE MUCH BETTER ENVIRONMENT WILL BE OFF TO OUR SOUTH AND EAST. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 320 PM CDT THU APR 23 2015 LONG WAVE TROUGH WILL BE MOVING INLAND FROM THE WEST COAST FRIDAY NIGHT...WITH A LEAD SHORTWAVE MOVING ACROSS THE CENTRAL PLAINS AHEAD OF THE TROUGH FRIDAY NIGHT. OPERATIONAL MODELS FCST THE CENTRAL PLAINS TROUGH TO BECOME CLOSED NEAR OR JUST WEST OF THE MID MISSOURI VALLEY. THIS WILL BE A RATHER DISORGANIZED EVENT...AND WITH ONLY WEAK MOISTURE TRANSPORT...LIFT WILL ALSO BE SOMEWHAT LIMITED AND UNFOCUSED. THIS CONTINUES TO SUGGEST A SHOWERY AND UNORGANIZED PRECIPITATION EVENT. WILL LIMIT HIGHEST POPS TO 40 TO 50 PERCENT EVENING AND 20 TO 30 PERCENT AFTER MIDNIGHT. BEST INSTABILITY ACROSS SERN ZONES...WITH HIGHER TSTM CHANCES WITH ONLY ISOLATED EXPECTED ACROSS THE NORTH/NORTHWEST. THE MAIN UPPER TROUGH WILL DIG SOUTHEAST ACROSS THE GREAT BASIN ON SATURDAY AS A TRANSITORY RIDGE MOVES INTO THE CNTRL PLAINS. THIS WILL LESSEN POPS TO ONLY A SLIGHT CHANCE NORTH AND WEST WITH PARTLY SUNNY SKIES AND HIGH TEMPS NEAR 60 NORTHEAST TO NEAR 70 FAR SOUTHWEST. THE GFS ENSEMBLE...GFS...AND ECMWF ALL AGREE THAT THE UPPER TROUGH WILL DEEPEN INTO THE FOUR CORNERS REGION SATURDAY NIGHT WITH AN AMPLIFIED SRLY FLOW ALOFT ACROSS THE CNTRL HIGH PLAINS. CHCS FOR SHOWERS AND THUNDERSTORMS WILL BE CONFINED TO THE HIGHS PLAINS WITH CHC POPS WEST OF HWY 83...AND NO WX ACROSS THE EAST. ANY SHOWERS THAT DEVELOP WILL MOVE NORTH WILL LITTLE OR NOW EASTWARD PROGRESSION. MEDIUM RANGE MODELS THEN INDICATED CLOSED LOW WILL TRACK EAST ACROSS NEW MEXICO...THE TEXAS PANHANDLE...AND THEN ACROSS NORTHERN TEXAS AND SOUTHERN OKLAHOMA SUNDAY THROUGH MONDAY NIGHT. THERE REMAINS ENOUGH MODEL AGREEMENT AND CONFIDENCE TO KEEP POPS INTO THE LIKELY CATEGORY ACROSS THE EASTERN PANHANDLE SUNDAY WITH CHC POPS EAST TO VALENTINE THROUGH BROKEN BOW. AS NRN STREAM TROUGH APPROACHES SUNDAY NIGHT AND MONDAY...POPS LESSEN AND REMAIN ONLY ACROSS THE WEST. DRY MONDAY NIGHT AND BEYOND. UPPER RIDGE OVER THE GREAT BASIN WILL SLOWLY BUILD EAST INTO THE CENTRAL CONUS THROUGH THURSDAY. THE COOLEST DAY LOOK TO BE SUNDAY AS EASTERLY UPSLOPE WINDS AND CLOUDINESS/SHOWERS LIMITS HIGHS TO LOWER MID 50S WEST TO NEAR 60 EAST. HIGHS THEN WARM INTO THE 60S MONDAY/TUESDAY...LOW 70S WEDNESDAY...THEN MID/UPPER 70S THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1154 PM CDT THU APR 23 2015 LOOK FOR LOW LEVEL CLOUDINESS TO DEVELOP OVERNIGHT AT BOTH THE KLBF AND KVTN TERMINALS. CIGS WILL RANGE FROM 700 TO 1500 FT AGL. LOOK FOR CIGS TO LIFT TO VFR FRIDAY AFTERNOON WITH CIGS RANGING FROM 10000 TO 20000 FT AGL. FOR FRIDAY EVENING...THERE WILL BE A THREAT FOR THUNDERSTORMS. GIVEN THE EXPECTED WIDELY SCATTERED COVERAGE...WILL HANDLE THIS WITH A PROB30 GROUP. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MARTIN SHORT TERM...MARTIN LONG TERM...ROBERG AVIATION...CLB
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
840 PM PDT SAT APR 25 2015 .SYNOPSIS...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CAN BE EXPECTED MAINLY ACROSS MOHAVE COUNTY TONIGHT. VERY STRONG WINDS ACROSS THE WESTERN MOJAVE DESERT WILL BE SUBSIDING OVERNIGHT. GUSTY NORTH WINDS ARE EXPECTED ACROSS THE REGION SUNDAY WITH IMPROVING CONDITIONS AND A WARMING TREND COMMENCING DURING THE WORKWEEK. && .UPDATE...A POTENT SHORT WAVE AND ITS ASSOCIATED COLD FRONT HAVE RESULTED IN QUITE AN ACTIVE AFTERNOON WEATHERWISE ACROSS THE REGION. WIDESPREAD RAINFALL WAS OBSERVED ACROSS MUCH OF SOUTHERN NEVADA INCLUDING THE LAS VEGAS METRO WHERE WIDESPREAD RAINFALL AMOUNTS BETWEEN 0.15 AND 0.35 WERE COMMON. THE OFFICIAL MEASUREMENT AT MCCARRAN OF 0.26 INCHES SHATTERED THE PREVIOUS RECORD OF 0.07 FOR THE DATE AND EXCEEDED THE NORMAL APRIL RAINFALL FOR THE ENTIRE MONTH. ACTIVITY IS NOW PUSHING INTO MOHAVE COUNTY AND SHOULD EXIT OUR EASTERN BORDERS LATE TONIGHT. WINDS ACROSS THE WESTERN MOJAVE DESERT HAVE EASED CONSIDERABLY WITH MUCH LIGHTER WINDS OBSERVED IN THE PAST COUPLE HOURS AT DAGGETT AND BICYCLE LAKE. SHOULD BE ABLE TO ALLOW THE WIND HEADLINES TO EXPIRE ON SCHEDULE IF NOT A LITTLE EARLY. IVE MADE SOME MINOR ADJUSTMENTS TO THE POP FORECAST OVERNIGHT TO ACCOUNT FOR CURRENT TRENDS AS WELL AS ADJUST CLOUD COVER. OTHERWISE THE FORECAST IS IN GOOD SHAPE. -OUTLER- && .SHORT TERM...THROUGH SUNDAY NIGHT. BROKEN LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS HAS DEVELOPED ALONG A COLD FRONT FROM DEATH VALLEY N.P - BEATTY - NORTHEAST OF RACHEL IN LINCOLN COUNTY. THIS FRONT IS ASSOCIATED WITH A POTENT SHORTWAVE TROUGH DIGGING INTO THE SOUTHERN GREAT BASIN/MOJAVE DESERT THIS AFTERNOON. LATEST HRRR SHOWS THIS BAND HOLDING TOGETHER AS IT CONTINUES TO MOVE SOUTHEAST AROUND 20-25 MPH. THAT WOULD PLACE THE LINE THROUGH THE PAHRUMP VALLEY BETWEEN 4-6 PM AND THE LAS VEGAS VALLEY BETWEEN 5 AND 7 PM. NORTHERN SEGMENT OF THE LINE WILL CONTINUE EAST ACROSS LINCOLN COUNTY WITH THE LINE FORECAST TO CLEAR LINCOLN COUNTY BETWEEN 6-7 PM. PRECIPITATION WILL BE LAST TO CLEAR THE LAKE MEAD NRA AND MOHAVE COUNTY WHICH WON`T OCCUR UNTIL AFTER MIDNIGHT. THUNDERSTORMS CAPABLE OF PRODUCING WIND GUSTS UP TO 40 MPH, SMALL HAIL AND BRIEF HEAVY RAIN. HIGH WIND WARNING PANNING OUT IN THE THE WESTERN MOJAVE DESERT OF SAN BERNARDINO COUNTY AS WE HAVE SEEN WIND GUSTS AT FORT IRWIN AND BARSTOW-DAGGETT IN EXCESS OF 60 MPH. WILL KEEP HIGH WIND WARNING AND WIND ADVISORY POSTED UNTIL 11 PM PDT. AN UPPER LOW WILL FORM OVER NEW MEXICO SUNDAY KEEPING THE REGION UNDER A COOL NORTH FLOW. IN ADDITION TO THE THOSE WIND PRODUCTS ALREADY OUT ADDED A WIND ADVISORY FOR POST FRONTAL NORTHWEST WINDS FOR ESMERALDA/CENTRAL NYE COUNTIES THROUGH SUNDAY AFTERNOON. ALSO, DECIDED TO ISSUE A LAKE WIND ADVISORY FOR THE LAKE MEAD NRA SOUTHWARD TO LAKE HAVASU. CAN NOT RULE OUT AN ISOLATED SHOWER OVER NORTHERN MOHAVE COUNTY WITHIN AN AREA OF WRAP AROUND MOISTURE. .LONG TERM...MONDAY THROUGH FRIDAY. ANY LINGERING SHOWERS WOULD BE OVER EXTREME EASTERN LINCOLN COUNTY AND EASTERN MOHAVE COUNTY EARLY BEFORE DRY CONDITIONS SET IN. EXPECT GUSTY NORTH WINDS OF 20-30 MPH ACROSS MUCH OF THE AREA, WITH HIGHER WIND SPEEDS LIKELY ALONG THE COLORADO RIVER VALLEY. WILL KEEP AN EYE ON THE POTENTIAL FOR A WIND HEADLINE FOR THE RIVER ZONES. BREEZY NORTH WINDS WILL LINGER INTO MONDAY, YET LIGHTER THAN SUNDAY. STRONGEST GUSTS WILL REMAIN ALONG THE COLORADO RIVER VALLEY. WINDS WILL BE WEAKER AND TREND TOWARD TYPICAL DIURNAL DIRECTIONS TUESDAY AND WEDNESDAY AS HIGH PRESSURE FULLY TAKES CONTROL. TEMPERATURES WILL ALSO TREND MUCH WARMER THROUGH THE WEEK, WITH AFTERNOON HIGHS CLIMBING ROUGHLY 10 DEGREES ABOVE NORMAL FOR THE LATTER HALF OF THE WEEK. THERE REMAINS SOME DIFFERENCE IN STRENGTH AND TIMING, BUT MODELS CONTINUE TO INDICATE A LOW PRESSURE SYSTEM MOVING THROUGH THE PACIFIC NORTHWEST /PERHAPS NORTHERN CALIFORNIA/ LATE THURSDAY THROUGH FRIDAY. SOME BREEZY SOUTHWEST WINDS ARE POSSIBLE THURSDAY AFTERNOON AND AGAIN FRIDAY. BREEZY CONDITIONS MAY LAST INTO THE WEEKEND, AS SOME WEAK TROUGHING LINGERS ACROSS THE GREAT BASIN. FOR NOW, IT APPEARS ANY MOISTURE WITH THIS TROUGH IS EXTREMELY LIMITED AND SHOULD STAY NORTH OF THE FORECAST AREA. && .AVIATION...FOR MCCARRAN...SCATTERED THUNDERSTORMS NEARING THE PAHRUMP VALLEY WILL CONTINUE TO DEVELOP EAST TOWARD THE LAS VEGAS VALLEY AFTER 4 PM. SHOWERS AND THUNDERSTORMS WILL CONTINUE AROUND THE LAS VEGAS VALLEY IMPACTING ALL CORRIDORS THROUGH ABOUT 7 PM THIS EVENING. THE WIND DIRECTION WILL GET DIFFICULT TO FORECAST WITH NEAR BY STORMS SO OPTED FOR A VARIABLE GROUPING IN THE TAF. SOME BLOWING DUST COULD ALSO BRING A REDUCTION IN THE VISIBILITY. NOT CONFIDENT ENOUGH AT THIS TIME TO MENTION THE LOWER VISIBILITY. AFTER THE STORMS CLEAR WINDS SHOULD SETTLE INTO A WESTERLY DIRECTION BEFORE GOING MORE NORTHWESTERLY LATE TONIGHT THROUGH SUNDAY. .FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...UNSETTLED WEATHER EXPECTED ACROSS THE REGION THIS EVENING WITH STRONG AND GUSTY WEST-SOUTHWEST WINDS EXPECTED ACROSS THE MOJAVE DESERT EASTWARD INTO NORTHWEST ARIZONA. WINDS OF 20 TO 30 KTS WITH GUSTS TO 40 EXPECTED WITH EVEN STRONGER WINDS IN THE KDAG AREA AND FAR WESTERN MOJAVE DESERT WHERE GUSTS WILL EXCEED 50KTS. AREAS OF BLOWING DUST LIKELY WITH DANGEROUS CROSSWINDS ON NORTH- SOUTH ORIENTED RUNWAYS. FURTHER NORTH WIDESPREAD SHOWERS AND TSTORMS LIKELY ACROSS THE SOUTHERN GREAT BASIN MAINLY NORTH OF I-15 THROUGH 00Z. SHOWERS EXPAND ACROSS NORTHWEST ARIZONA AND FAR SOUTHERN NEVADA AFTER 00Z AS A COLD FRONT MOVES THROUGH AND WINDS SHIFT TO THE NORTHWEST. && .SPOTTER INFORMATION STATEMENT...SPOTTERS SHOULD REPORT ACCORDING TO STANDARD OPERATING PROCEDURES. && $$ SHORT TERM/AVIATION...STACHELSKI LONG TERM...PIERCE FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE: HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS ELKO NV
326 PM PDT FRI APR 24 2015 .SYNOPSIS...VALLEY RAIN AND MOUNTAIN SNOW TODAY AND AGAIN ON SATURDAY. ALSO ON SATURDAY...WINDS WILL BECOME GUSTY AND MOST AREAS WILL HAVE A SLIGHT CHANCE OF THUNDERSTORMS. SATURDAY EVENING SNOW LEVELS WILL LOWER TO VALLEY FLOORS AS PRECIPITATION BEGINS TO TAPER OFF. COOL AND DRY ON SUNDAY WITH A WARMING TREND NEXT WEEK. && .SHORT TERM...TONIGHT THROUGH MONDAY. CURRENTLY...A SHORTWAVE IS MOVING THROUGH NORTHERN NEVADA. THIS SHOWS UP NICELY ON THE WATER VAPOR. THIS WILL CONTINUE TO SLIDE EASTWARD THROUGH THE EVENING...DEVELOPING/MAINTAINING LIGHT TO MODERATE RAIN SHOWERS AND AN ISOLATED THUNDERSTORM OR TWO. ANY ONE SHOWER COULD DROP ~0.25 INCHES OF RAIN. THE HRRR SHOWS CONVECTION ENDING AROUND 00Z TO 03Z FROM WEST TO EAST. WE WILL HAVE A BRIEF BREAK FROM SHOWERS LATER THIS EVENING...BUT THAT WILL BE SHORT LIVED AS THE NEXT WAVE DROPS IN FROM THE NORTHWEST. THIS TROUGH IS MUCH STRONGER AND IS NEGATIVELY TILTED. DUE TO THE NEGATIVE TILT OF THE TROUGH...THE MODELS MAY BE A TAD TOO QUICK WITH THE TROUGH. THEREFORE...THE HIGHEST QPF/SNOW AMOUNTS ARE IN WHITE PINE AND NE NYE COUNTIES. ISOLATED TS WILL AGAIN BE POSSIBLE ON SATURDAY...MAINLY EAST OF HIGHWAY 95. SNOW LEVELS WILL START OUT ABOVE 7000FT...BUT WILL LOWER TO MOST VALLEY FLOORS BETWEEN 5500-6500FT THROUGH THE AFTERNOON/EVENING. SNOW LEVELS IN FAR NW NV WILL START OUT AROUND 6500FT AND LOWER TO 5000FT BY SATURDAY EVENING. EXPECTING LITTLE...IF ANY...IMPACTS IN THE VALLEYS. THE COLD AIR WILL BE SLOW TO ARRIVE...AND GIVEN THE HIGH SUN ANGLE...ROADS SHOULD REMAIN WET. ANY IMPACTS WILL BE ABOVE 6500FT...BUT WILL STILL BE MINIMAL GIVEN THE TIME OF YEAR. A TRACE TO ONE INCH OF SNOW WILL BE POSSIBLE BELOW 6500FT...WITH SEVERAL INCHES IN THE MOUNTAINS. SOME OF THE HIGHER ELEVATION VALLEYS IN NORTHERN ELKO AND WHITE PINE COUNTIES COULD LOCALLY SEE UP TO 3 INCHES. LOCALLY A FOOT OF SNOW COULD FALL IN THE HIGHEST MTNS IN WHITE PINE AND NE NYE COUNTIES. IN ADDITION...GUSTY NW WINDS WILL DEVELOP SATURDAY EVENING THROUGH SUNDAY AFTERNOON. NW NYE WILL APPROACH WIND ADV CRITERIA DUE TO PRESSURE GRADIENT/PRESSURE FALLS. MAV/MET GUIDANCE SUPPORTS STRONG GUSTS AND THIS WILL BE MONITORED FOR AN ADV. BY SUNDAY MORNING...MOST LOCATIONS WILL BE DRY. A WARMING TREND WILL COMMENCE ON MONDAY...WHERE 60S/70S WILL BE PREVALENT. .LONG TERM...MONDAY NIGHT THROUGH FRIDAY. MODELS IN FAIRLY GOOD AGREEMENT WITH THE OVERALL PATTERN THROUGH WEDNESDAY NIGHT. RIDGE BUILDING IN FROM THE WEST MONDAY NIGHT WITH RIDGE AXIS OVER THE CWA BY 18Z TUESDAY FOR A WARMING TREND AND DRY CONDITIONS. SHORTWAVE PASSING TO THE NORTHWEST FLATTENS THE RIDGE A BIT BUT KEEPS WARM SOUTHWEST FLOW OVER OUR REGION...WITH TEMPERATURES NEAR 80 DEGREES BY WEDNESDAY. 12Z MODELS DIFFER WITH GFS NOW TRYING TO DIG A STRONG TROF INTO NORTHERN CA WHILE THE EC MUCH WEAKER WITH THIS SHORTWAVE. STILL...EITHER SOLUTION WOULD KEEP THE CWA DRY...BUT GFS WOULD IMPLY WINDY CONDITIONS AND SOME INSTABILITY IN CENTRAL NV. UNTIL MODELS COME INTO BETTER AGREEMENT...RIGHT NOW WILL LEAN TOWARD WEAKER EC MODEL IN KEEPING THE CWA DRY WITH LESS WIND AND STABILITY. && .AVIATION...RAIN SHOWERS OVER THE CWA WILL DECREASE THIS EVENING BRIEFLY BEFORE INCREASING AGAIN AFTER 10Z AT KWMC...18Z AT KEKO ...AND 20Z AT KELY. THUS ON SATURDAY...CIGS ARE EXPECTED TO LOWER TO AT LEAST MVFR AND PERHAPS BRIEFLY IFR AT THESE TERMINALS. WINDS WILL BE GUSTY AT THE TERMINALS THROUGH 03Z THIS EVENING. && .LKN WATCHES/WARNINGS/ADVISORIES...NONE. && $$ 94/87/87
AREA FORECAST DISCUSSION
NWS ELKO NV
1159 AM PDT FRI APR 24 2015 .SYNOPSIS...VALLEY RAIN AND MOUNTAIN SNOW TODAY AND AGAIN ON SATURDAY. ALSO ON SATURDAY WINDS WILL BECOME GUSTY AND MOST AREAS WILL HAVE A SLIGHT CHANCE OF THUNDERSTORMS. SATURDAY EVENING SNOW LEVELS WILL LOWER TO VALLEY FLOORS AS PRECIPITATION BEGINS TO TAPER OFF. COOL AND DRY ON SUNDAY WITH A WARMING TREND NEXT WEEK. && .SHORT TERM UPDATE...DECIDED TO INCLUDE SLIGHT CHANCE OF THUNDER FOR THE REST OF THIS AFTERNOON. MARGINAL INSTABILITY AND APPROACHING SHORTWAVE WILL PROMOTE SOME ISOLATED TS. CURRENT RADAR TRENDS ARE SHOWING SOME ENHANCED CORES MOVING IN FROM PERSHING/CHURCHILL COUNTIES. HRRR SHOWS THESE SHOWERS MOVING EASTWARD THROUGHOUT THE DAY. .PREV DISCUSSION... /ISSUED AT 322 AM / SYNOPSIS...VALLEY RAIN AND MOUNTAIN SNOW TODAY AND AGAIN ON SATURDAY. ALSO ON SATURDAY WINDS WILL BECOME GUSTY AND MOST AREAS WILL HAVE A SLIGHT CHANCE OF THUNDERSTORMS. SATURDAY EVENING SNOW LEVELS WILL LOWER TO VALLEY FLOORS AS PRECIPITATION BEGINS TO TAPER OFF. COOL AND DRY ON SUNDAY WITH A WARMING TREND NEXT WEEK. SHORT TERM...TODAY THROUGH SUNDAY. TROUGH DROPPING INTO THE PACIFIC NORTHWEST THIS MORNING WITH ASSOCIATED JET MOVING OVER NORTHERN CALIFORNIA AND NEVADA. AS A RESULT PRECIPITATION WILL SPREAD NORTHWEST TO SOUTHEAST ACROSS NEVADA TODAY WITH RAIN IN THE VALLEYS AND SNOW IN THE MOUNTAINS. MANY VALLEY LOCATIONS WILL RECEIVE A TENTH OF AN INCH OF RAIN TODAY. WEAK INSTABILITY SETS UP ACROSS EAST-CENTRAL NEVADA THIS AFTERNOON WHICH MAY TRIGGER SOME ISOLATED THUNDERSTORMS. BEST CHANCES FOR TS WILL BE OVER AND NEAR GREAT BASIN PARK THIS AFTERNOON WHICH COULD ENHANCE PRECIPITATION AMOUNTS. THE FIRST WAVE OF MOISTURE EXITS EAST INTO UTAH THIS EVENING FOLLOWED ALMOST IMMEDIATELY WITH ANOTHER ROUND OF MOISTURE APPROACHING FROM THE WEST. THIS SECOND SYSTEM TONIGHT INTO SATURDAY HAS THE POTENTIAL TO SPREAD MODERATE PRECIPITATION TO MUCH OF THE REGION. ONE TO THREE TENTHS OF AN INCH OF QPF WILL BE COMMON ON SATURDAY...WITH HIGHER AMOUNTS POSSIBLE. MANY OF THE MOUNTAINS ACROSS NORTHERN AND CENTRAL NEVADA WILL ADD ANOTHER 2-6 INCHES OF SNOW ON SATURDAY. MAY NEED TO CONSIDER AN ELEVATION BASED WINTER WEATHER ADVISORY FOR SATURDAY AS SNOW AND BLOWING SNOW ABOVE 6500-7000 FEET MAY BE A CONCERN...ESPECIALLY WITH RESPECT TO REDUCED VISIBILITIES ON HIGH ELEVATION SUMMITS. SHOWER ACTIVITY EXITS INTO UTAH SATURDAY NIGHT...THIS TIME FOLLOWED UP WITH RIDGING BUILDING IN FROM THE WEST. COLD NORTHERLY FLOW ALOFT SUNDAY MORNING WILL RESULT IN TEMPERATURES FALLING BACK INTO THE 20S FOR MANY LOCATIONS. IF SKIES SCATTER OUT OR CLEAR COMPLETELY EARLY SUNDAY...SOME VALLEYS MAY SEE SOME FREEZING FOG. NORTHERLY FLOW SUNDAY WILL KEEP HIGHS ON THE COOL SIDE...GENERALLY UPPER 50S...WHICH WOULD BE 5-10 DEGREES BELOW NORMAL. LONG TERM...SUNDAY NIGHT THROUGH THURSDAY. TROUGH WILL BE EXITING THE AREA TO OUR EAST SUNDAY NIGHT WITH RIDGE BUILDING IN FROM THE WEST. THIS TREND WILL CONTINUE THROUGH TUESDAY WITH QUICKLY WARMING TEMPERATURES AND SUNNY SKIES. SHORTWAVE PASSING TO THE NORTHWEST FLATTENS THE RIDGE A BIT BUT KEEPS WARM SOUTHWEST FLOW OVER OUR REGION...WITH TEMPERATURES NOW LOOKING LIKE THEY WILL APPROACH OR EXCEED 80 ACROSS MUCH OF THE CWA`S VALLEYS ON WEDNESDAY. DESPITE OUR VERY WARM LATE WINTER AND EARLY SPRING...THIS WOULD BE THE FIRST 80 OF THE YEAR IN MOST LOCALES. ANOTHER SHORTWAVE APPROACHING OR PASSING TO THE NORTHWEST ON THURSDAY WOULD LIKELY KNOCK TEMPS DOWN A BIT BUT IT SHOULD REMAIN VERY WARM AND DRY WITH THE RIDGE AXIS NOT FAR AWAY TO OUR SOUTHEAST. RCM AVIATION...RAIN SHOWERS WILL OVERSPREAD MUCH OF THE CWA FROM WEST TO EAST LATE TONIGHT AND FRIDAY. NORTHERN AND WESTERN TERMINALS SHOULD AVOID THUNDER...BUT THUNDERSTORMS MAY DEVELOP FURTHER SOUTH AND EAST AROUND KELY AND KTPH LATER IN THE DAY. CIGS LOOK TO LOWER TO AT LEAST MVFR AND PERHAPS BRIEFLY IFR AT THE NORTHERN TERMINALS AS THE SHOWERS MOVE IN...BUT SHOULD STAY HIGHER FOR THE MOST PART FURTHER SOUTH. WINDS WILL BE GUSTY BY THIS AFTERNOON AT ALL TERMINALS WITH A FEW GUSTS UP AROUND 30 KNOTS POSSIBLE. CONDITIONS WILL GENERALLY IMPROVE IN ALL REGARDS THIS EVENING. RCM && .LKN WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 94/99
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1046 AM EDT FRI APR 24 2015 .SYNOPSIS... A SLOW MOVING LOW PRESSURE SYSTEM IN THE UPPER LEVELS OF THE ATMOSPHERE WILL BE THE MAIN FEATURE ON THE WEATHER MAP. THE LOW WILL REMAIN IN THE AREA THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK, AND PRODUCE SCATTERED SHOWERS, WITH SNOW SHOWERS AT THE HIGHER ELEVATIONS. IT WILL CONTINUE TO BE RATHER CLOUDY WITH BELOW NORMAL TEMPERATURES. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1046 AM EDT FRIDAY...HAVE LOWERED MAX TEMPERATURES FOR TODAY SEVERAL DEGREES FROM THE PREVIOUS FORECAST...BASED ON CURRENT SURFACE OBSERVATIONS...THE LATEST GFS LAMP GUIDANCE AND THE 06Z GFS MOS GUIDANCE. FORECAST AREA REMAINS UNDER CYCLONIC FLOW FROM A SURFACE LOW PRESSURE AREA AND AN UPPER LOW OVER THE CANADIAN MARITIMES. WILL CONTINUE TO KEEP IN LOW CHANCE POPS FOR RAIN OR SNOW SHOWERS TODAY...WITH SNOW SHOWERS MAINLY OVER THE HIGHER ELEVATIONS DURING THE DAY TODAY. PREVIOUS DISCUSSION FROM 638 AM EDT FRIDAY...JUST A ROUTINE LITTLE REFRESH TO INJECT CURRENT OBSERVATION/RADAR TRENDS INTO THE FIRST FEW HOURS OF THE FORECAST. A FEW SNOW SHOWERS HAVE AGAIN BLOSSOMED ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS, JUST EAST OF BURLINGTON. 06Z NAM DIAGNOSTICS INDICATE THE FLOW IS STILL MARGINALLY BLOCKED WITH RESPECT TO THE GREEN MOUNTAINS. THAT IS PROBABLY CONTRIBUTING TO THE FORMATION OF THESE FLURRIES/SNOW SHOWERS. FLOW GOES UNBLOCKED A BIT LATER THIS MORNING. I LIKED THE 09Z HRRR DEPICTION OF THE PRECIPITATION FOR TODAY, AND MADE SLIGHT ADJUSTMENTS TO THE POPS TO BE SOMEWHAT IN LINE WITH THAT GUIDANCE. THUS, THE CURRENT FLURRIES/SNOW SHOWERS SHOULD COME TO AN END SHORTLY, THEN A BREAK, THEN SCATTERED LIGHT RAIN/SNOW SHOWERS THIS AFTERNOON ACROSS THE HIGHER TERRAIN. WHAT FOLLOWS ARE THE RAMBLINGS FROM EARLIER THIS MORNING... SLOW MOVING UPPER LOW CENTERED OVER MAINE AT THIS EARLY HOUR. RATHER ABUNDANT MOISTURE IS ROTATING AROUND THIS LOW, WITH ONE AREA OF SLIGHTLY DEEPER MOISTURE (AS EVIDENT WITH THE COOLER CLOUD TOPS ON IR SATELLITE) LOCATED ACROSS NORTHERN VERMONT. THIS IS RESPONSIBLE FOR THE LIGHT SNOWS, PRIMARILY ACROSS THE HIGHER ELEVATION. THIS MOISTURE IS SLOWLY MOVING EAST AND THE CLOUD TOPS ARE WARMING -- A SIGNAL THAT THE SNOW SHOWERS WILL BE DIMINISHING OVER THE NEXT 6 HOURS OR SO. A MODERATE SURFACE PRESSURE GRADIENT IS IN PLACE ACROSS THE AREA BETWEEN HIGH PRESSURE WELL TO THE WEST AND A WEAK AREA OF LOW PRESSURE TO THE EAST. THUS IT WILL BE A LITTLE BREEZY TODAY, WITH NORTHWEST WINDS GENERALLY IN THE 10-20MPH RANGE. LOOKS LIKE THE BOUNDARY LAYER WILL MIX TO ROUGHLY 3000-4000FT, AND WINDS UP AT THAT LEVEL ARE JUST A TAD STRONGER, SO NOT OUT OF THE QUESTION TO SEE A FEW GUSTS OVER 25 MPH. OF NOTE WILL BE THE CHILLY TEMPERATURES. 850MB TEMPERATURES ALOFT ARE ON THE ORDER OF -2C TO -4C, WHICH UNDER PERFECTLY SUNNY CONDITIONS WOULD SUPPORT HIGHS ONLY IN THE LOWER 50S. HOWEVER, GIVEN THE CLOUDS, WE`LL BE A LITTLE LOWER THAN THAT, AND SHOULD WORK OUT TO BE VERY SIMILAR TO YESTERDAY. THUS MID/UPPER 40S IN THE VALLEYS AND UPPER 30S TO LOWER 40S AT HIGHER ELEVATIONS. WITH THE COLD POOL ALOFT, WE WILL SEE A LITTLE BIT OF DESTABLIZATION THIS AFTERNOON, SO EXPECT SCATTERED SHOWERS TO DEVELOP, MAINLY ACROSS THE HIGHER TERRAIN OF VERMONT AND NORTHERN NEW YORK. ELEVATION WILL CONTROL WHETHER IT WILL BE RAIN OR SNOW. IN GENERAL, SNOW LEVELS THIS AFTERNOON WILL BE RUNNING ABOUT 1200 FEET. ACCUMULATIONS WILL BE VERY MINOR. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/... AS OF 350 AM EDT FRIDAY...THAT PESKY UPPER LOW WILL BE...WELL, PESKY...ALL THE WAY INTO SUNDAY. MODELS ALL SHOW THE CURRENT UPPER LOW OVER MAINE MOVING SOUTHEAST, HOWEVER ANOTHER LOW ROTATES IN TO TAKE IT`S PLACE. REGARDLESS OF WHAT IS HAPPENING ALOFT, THE NET RESULT FOR US ON THE GROUND WILL BE CONTINUED COOL, UNSETTLED CONDITIONS WITH RAIN/SNOW SHOWERS SCATTERED ABOUT. I THINK MOST OF THE SHOWERS WILL BE MORE CONFINED TO THE HIGHER TERRAIN, THANKS TO SOME OROGRAPHIC INFLUENCES FROM THE NORTHWESTERLY FLOW. INDICATIONS IN MODEL GUIDANCE THAT A LOW LEVEL BLOCKED FLOW WILL AGAIN DEVELOP LATER TONIGHT AND FIRST THING SATURDAY, SO PRECIPITATION MAY REFOCUS ITSELF A BIT MORE ALONG THE WEST SLOPES OF THE NORTHERN GREEN MOUNTAINS AT THAT TIME, THOUGH NOT EXPECTING HEAVY, SO JUST ANOTHER ROUND OF A DUSTING TO 1/2" OF SNOW. SHOULD BE ANOTHER SURGE OF DEEPER MOISTURE THAT ROTATES IN FROM THE NORTHEAST LATE SATURDAY NIGHT AND INTO SUNDAY MORNING. HAVE TRIED TO PAINT IN AN INCREASE OF POPS FROM NORTHERN VERMONT INITIALLY AND THEN SOUTHWARD ACROSS THE REGION DURING SUNDAY. STILL DON`T THINK IT WILL BE A VERY WIDESPREAD PRECIPITATION EVENT, JUST MORE IN THE WAY OF SCATTERED SHOWERS (RAIN & SNOW STILL DEPENDING ON ELEVATION). TEMPERATURES DO LOOK LIKE THEY WILL EVERY SO SLOWLY MODERATE EACH DAY AS THE FLOW ACROSS THE AREA TAKES ON MORE OF AN ATLANTIC OCEAN SOURCE, BUT STILL BE BELOW NORMAL. HUNG WITH A MIX OF GUIDANCE, SO LOOK FOR DAYTIME HIGHS IN THE 50S BOTH WEEKEND DAYS AND OVERNIGHT LOWS GENERALLY IN THE 30S. COLDER AT HIGHER ELEVATIONS. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 356 AM EDT FRIDAY...LATE WEEKEND/EARLY NEXT WEEK STILL INFLUENCED BY CLOSED UPPER LOW IN GULF OF MAINE SLOWLY EXITING EAST BY MID WEEK FOLLOWED BY PERHAPS ANOTHER TROUGH OR CUT OFF BY LATE NEXT WEEK. THE INFLUENCE OF CLOSED UPPER LOW DIMINISHES WITH TIME WITH BEST CHANCE OF RAIN SHOWERS BEING SUNDAY NIGHT THROUGH MONDAY-MONDAY NIGHT. COLD ENOUGH ALOFT THAT SOME SNOW SHOWERS POSSIBLE IN HIGHER ELEVATIONS AT NIGHT. SOME SHORT WAVE RIDGING TRYING TO SQUEEZE INTO THIS UGLY FLOW PATTERN FOR TUE-WED THEN MODELS DIFFER ON TIMING/STRENGTH OF NEXT POTENTIAL TROUGH/UPPER LOW FOR LATE NEXT WEEK. TEMPERATURES REMAIN COOLER THAN NORMAL (NORMAL U50S-L60S)THROUGH MON THEN NEAR NORMAL MID WEEK PERHAPS TURNING COOLER TOWARD END OF NEXT WEEK. MIN TEMPERATURES LARGELY 30S-L40S WITH UPPER 20S IN HIGHER ELEVATIONS. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... THROUGH 12Z SATURDAY...PRIMARILY VFR THROUGH 00Z SATURDAY UNDER A BKN-OVC SKY. SOME INSTABILITY/WRAPAROUND SHOWERS MAY RETURN...MAINLY ACROSS MOUNTAINS AFT 21Z FRI AND BECOME MORE WIDESPREAD AFT 00Z SAT...AFT 00Z POSSIBLE MVFR AT KSLK/KMPV. SURFACE WINDS WNW 10-15 KNOTS WITH SOME GUSTS UP TO 20 KNOTS. OUTLOOK 12Z SATURDAY THROUGH TUESDAY... FOR THE ENTIRE PERIOD - VFR WITH PERIODS OF MVFR (AND POSSIBLY BRIEF IFR) IN SCATTERED RAIN SHOWERS DURING THE DAY AND RAIN/SNOW SHOWERS AT NIGHT. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...NASH NEAR TERM...WGH/NASH SHORT TERM...NASH LONG TERM...SLW AVIATION...SLW
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
737 AM EDT FRI APR 24 2015 .SYNOPSIS... A SLOW MOVING LOW PRESSURE SYSTEM IN THE UPPER LEVELS OF THE ATMOSPHERE WILL BE THE MAIN FEATURE ON THE WEATHER MAP. THE LOW WILL REMAIN IN THE AREA THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK, AND PRODUCE SCATTERED SHOWERS, WITH SNOW SHOWERS AT THE HIGHER ELEVATIONS. IT WILL CONTINUE TO BE RATHER CLOUDY WITH BELOW NORMAL TEMPERATURES. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 638 AM EDT FRIDAY...JUST A ROUTINE LITTLE REFRESH TO INJECT CURRENT OBSERVATION/RADAR TRENDS INTO THE FIRST FEW HOURS OF THE FORECAST. A FEW SNOW SHOWERS HAVE AGAIN BLOSSOMED ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS, JUST EAST OF BURLINGTON. 06Z NAM DIAGNOSTICS INDICATE THE FLOW IS STILL MARGINALLY BLOCKED WITH RESPECT TO THE GREEN MOUNTAINS. THAT IS PROBABLY CONTRIBUTING TO THE FORMATION OF THESE FLURRIES/SNOW SHOWERS. FLOW GOES UNBLOCKED A BIT LATER THIS MORNING. I LIKED THE 09Z HRRR DEPICTION OF THE PRECIPITATION FOR TODAY, AND MADE SLIGHT ADJUSTMENTS TO THE POPS TO BE SOMEWHAT IN LINE WITH THAT GUIDANCE. THUS, THE CURRENT FLURRIES/SNOW SHOWERS SHOULD COME TO AN END SHORTLY, THEN A BREAK, THEN SCATTERED LIGHT RAIN/SNOW SHOWERS THIS AFTERNOON ACROSS THE HIGHER TERRAIN. WHAT FOLLOWS ARE THE RAMBLINGS FROM EARLIER THIS MORNING... SLOW MOVING UPPER LOW CENTERED OVER MAINE AT THIS EARLY HOUR. RATHER ABUNDANT MOISTURE IS ROTATING AROUND THIS LOW, WITH ONE AREA OF SLIGHTLY DEEPER MOISTURE (AS EVIDENT WITH THE COOLER CLOUD TOPS ON IR SATELLITE) LOCATED ACROSS NORTHERN VERMONT. THIS IS RESPONSIBLE FOR THE LIGHT SNOWS, PRIMARILY ACROSS THE HIGHER ELEVATION. THIS MOISTURE IS SLOWLY MOVING EAST AND THE CLOUD TOPS ARE WARMING -- A SIGNAL THAT THE SNOW SHOWERS WILL BE DIMINISHING OVER THE NEXT 6 HOURS OR SO. A MODERATE SURFACE PRESSURE GRADIENT IS IN PLACE ACROSS THE AREA BETWEEN HIGH PRESSURE WELL TO THE WEST AND A WEAK AREA OF LOW PRESSURE TO THE EAST. THUS IT WILL BE A LITTLE BREEZY TODAY, WITH NORTHWEST WINDS GENERALLY IN THE 10-20MPH RANGE. LOOKS LIKE THE BOUNDARY LAYER WILL MIX TO ROUGHLY 3000-4000FT, AND WINDS UP AT THAT LEVEL ARE JUST A TAD STRONGER, SO NOT OUT OF THE QUESTION TO SEE A FEW GUSTS OVER 25 MPH. OF NOTE WILL BE THE CHILLY TEMPERATURES. 850MB TEMPERATURES ALOFT ARE ON THE ORDER OF -2C TO -4C, WHICH UNDER PERFECTLY SUNNY CONDITIONS WOULD SUPPORT HIGHS ONLY IN THE LOWER 50S. HOWEVER, GIVEN THE CLOUDS, WE`LL BE A LITTLE LOWER THAN THAT, AND SHOULD WORK OUT TO BE VERY SIMILAR TO YESTERDAY. THUS MID/UPPER 40S IN THE VALLEYS AND UPPER 30S TO LOWER 40S AT HIGHER ELEVATIONS. WITH THE COLD POOL ALOFT, WE WILL SEE A LITTLE BIT OF DESTABLIZATION THIS AFTERNOON, SO EXPECT SCATTERED SHOWERS TO DEVELOP, MAINLY ACROSS THE HIGHER TERRAIN OF VERMONT AND NORTHERN NEW YORK. ELEVATION WILL CONTROL WHETHER IT WILL BE RAIN OR SNOW. IN GENERAL, SNOW LEVELS THIS AFTERNOON WILL BE RUNNING ABOUT 1200 FEET. ACCUMULATIONS WILL BE VERY MINOR. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/... AS OF 350 AM EDT FRIDAY...THAT PESKY UPPER LOW WILL BE...WELL, PESKY...ALL THE WAY INTO SUNDAY. MODELS ALL SHOW THE CURRENT UPPER LOW OVER MAINE MOVING SOUTHEAST, HOWEVER ANOTHER LOW ROTATES IN TO TAKE IT`S PLACE. REGARDLESS OF WHAT IS HAPPENING ALOFT, THE NET RESULT FOR US ON THE GROUND WILL BE CONTINUED COOL, UNSETTLED CONDITIONS WITH RAIN/SNOW SHOWERS SCATTERED ABOUT. I THINK MOST OF THE SHOWERS WILL BE MORE CONFINED TO THE HIGHER TERRAIN, THANKS TO SOME OROGRAPHIC INFLUENCES FROM THE NORTHWESTERLY FLOW. INDICATIONS IN MODEL GUIDANCE THAT A LOW LEVEL BLOCKED FLOW WILL AGAIN DEVELOP LATER TONIGHT AND FIRST THING SATURDAY, SO PRECIPITATION MAY REFOCUS ITSELF A BIT MORE ALONG THE WEST SLOPES OF THE NORTHERN GREEN MOUNTAINS AT THAT TIME, THOUGH NOT EXPECTING HEAVY, SO JUST ANOTHER ROUND OF A DUSTING TO 1/2" OF SNOW. SHOULD BE ANOTHER SURGE OF DEEPER MOISTURE THAT ROTATES IN FROM THE NORTHEAST LATE SATURDAY NIGHT AND INTO SUNDAY MORNING. HAVE TRIED TO PAINT IN AN INCREASE OF POPS FROM NORTHERN VERMONT INITIALLY AND THEN SOUTHWARD ACROSS THE REGION DURING SUNDAY. STILL DON`T THINK IT WILL BE A VERY WIDESPREAD PRECIPITATION EVENT, JUST MORE IN THE WAY OF SCATTERED SHOWERS (RAIN & SNOW STILL DEPENDING ON ELEVATION). TEMPERATURES DO LOOK LIKE THEY WILL EVERY SO SLOWLY MODERATE EACH DAY AS THE FLOW ACROSS THE AREA TAKES ON MORE OF AN ATLANTIC OCEAN SOURCE, BUT STILL BE BELOW NORMAL. HUNG WITH A MIX OF GUIDANCE, SO LOOK FOR DAYTIME HIGHS IN THE 50S BOTH WEEKEND DAYS AND OVERNIGHT LOWS GENERALLY IN THE 30S. COLDER AT HIGHER ELEVATIONS. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 356 AM EDT FRIDAY...LATE WEEKEND/EARLY NEXT WEEK STILL INFLUENCED BY CLOSED UPPER LOW IN GULF OF MAINE SLOWLY EXITING EAST BY MID WEEK FOLLOWED BY PERHAPS ANOTHER TROUGH OR CUT OFF BY LATE NEXT WEEK. THE INFLUENCE OF CLOSED UPPER LOW DIMINISHES WITH TIME WITH BEST CHANCE OF RAIN SHOWERS BEING SUNDAY NIGHT THROUGH MONDAY-MONDAY NIGHT. COLD ENOUGH ALOFT THAT SOME SNOW SHOWERS POSSIBLE IN HIGHER ELEVATIONS AT NIGHT. SOME SHORT WAVE RIDGING TRYING TO SQUEEZE INTO THIS UGLY FLOW PATTERN FOR TUE-WED THEN MODELS DIFFER ON TIMING/STRENGTH OF NEXT POTENTIAL TROUGH/UPPER LOW FOR LATE NEXT WEEK. TEMPERATURES REMAIN COOLER THAN NORMAL (NORMAL U50S-L60S)THROUGH MON THEN NEAR NORMAL MID WEEK PERHAPS TURNING COOLER TOWARD END OF NEXT WEEK. MIN TEMPERATURES LARGELY 30S-L40S WITH UPPER 20S IN HIGHER ELEVATIONS. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... THROUGH 12Z SATURDAY...PRIMARILY VFR THROUGH 00Z SATURDAY UNDER A BKN-OVC SKY. SOME INSTABILITY/WRAPAROUND SHOWERS MAY RETURN...MAINLY ACROSS MOUNTAINS AFT 21Z FRI AND BECOME MORE WIDESPREAD AFT 00Z SAT...AFT 00Z POSSIBLE MVFR AT KSLK/KMPV. SURFACE WINDS WNW 10-15 KNOTS WITH SOME GUSTS UP TO 20 KNOTS. OUTLOOK 12Z SATURDAY THROUGH TUESDAY... FOR THE ENTIRE PERIOD - VFR WITH PERIODS OF MVFR (AND POSSIBLY BRIEF IFR) IN SCATTERED RAIN SHOWERS DURING THE DAY AND RAIN/SNOW SHOWERS AT NIGHT. && .HYDROLOGY... UPDATED 1102 PM THURSDAY...THE FLOOD WARNING CONTINUES FOR THE BARTON RIVER NEAR COVENTRY. THE RIVER WENT ABOVE FLOOD STAGE EARLY THIS MORNING AND WENT UP QUICKLY...CRESTING AROUND 8.8 FEET THIS AFTERNOON. SINCE THEN...THE WATER LEVEL OF THE RIVER HAS BEGUN TO FALL...AND AT 11 PM IT WAS AT 8.4 FEET. EXPECT THIS TREND TO CONTINUE OVERNIGHT. CURRENTLY THE BARTON RIVER NEAR COVENTRY IS THE ONLY RIVER THAT WE EXPECT TO REACH FLOOD STAGE AS MOST OF THE OTHER RIVERS AND STREAMS HAVE CRESTED BELOW FLOOD STAGE. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...NASH NEAR TERM...NASH SHORT TERM...NASH LONG TERM...SLW AVIATION...SLW HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
646 AM EDT FRI APR 24 2015 .SYNOPSIS... A SLOW MOVING LOW PRESSURE SYSTEM IN THE UPPER LEVELS OF THE ATMOSPHERE WILL BE THE MAIN FEATURE ON THE WEATHER MAP. THE LOW WILL REMAIN IN THE AREA THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK, AND PRODUCE SCATTERED SHOWERS, WITH SNOW SHOWERS AT THE HIGHER ELEVATIONS. IT WILL CONTINUE TO BE RATHER CLOUDY WITH BELOW NORMAL TEMPERATURES. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 638 AM EDT FRIDAY...JUST A ROUTINE LITTLE REFRESH TO INJECT CURRENT OBSERVATION/RADAR TRENDS INTO THE FIRST FEW HOURS OF THE FORECAST. A FEW SNOW SHOWERS HAVE AGAIN BLOSSOMED ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS, JUST EAST OF BURLINGTON. 06Z NAM DIAGNOSTICS INDICATE THE FLOW IS STILL MARGINALLY BLOCKED WITH RESPECT TO THE GREEN MOUNTAINS. THAT IS PROBABLY CONTRIBUTING TO THE FORMATION OF THESE FLURRIES/SNOW SHOWERS. FLOW GOES UNBLOCKED A BIT LATER THIS MORNING. I LIKED THE 09Z HRRR DEPICTION OF THE PRECIPITATION FOR TODAY, AND MADE SLIGHT ADJUSTMENTS TO THE POPS TO BE SOMEWHAT IN LINE WITH THAT GUIDANCE. THUS, THE CURRENT FLURRIES/SNOW SHOWERS SHOULD COME TO AN END SHORTLY, THEN A BREAK, THEN SCATTERED LIGHT RAIN/SNOW SHOWERS THIS AFTERNOON ACROSS THE HIGHER TERRAIN. WHAT FOLLOWS ARE THE RAMBLINGS FROM EARLIER THIS MORNING... SLOW MOVING UPPER LOW CENTERED OVER MAINE AT THIS EARLY HOUR. RATHER ABUNDANT MOISTURE IS ROTATING AROUND THIS LOW, WITH ONE AREA OF SLIGHTLY DEEPER MOISTURE (AS EVIDENT WITH THE COOLER CLOUD TOPS ON IR SATELLITE) LOCATED ACROSS NORTHERN VERMONT. THIS IS RESPONSIBLE FOR THE LIGHT SNOWS, PRIMARILY ACROSS THE HIGHER ELEVATION. THIS MOISTURE IS SLOWLY MOVING EAST AND THE CLOUD TOPS ARE WARMING -- A SIGNAL THAT THE SNOW SHOWERS WILL BE DIMINISHING OVER THE NEXT 6 HOURS OR SO. A MODERATE SURFACE PRESSURE GRADIENT IS IN PLACE ACROSS THE AREA BETWEEN HIGH PRESSURE WELL TO THE WEST AND A WEAK AREA OF LOW PRESSURE TO THE EAST. THUS IT WILL BE A LITTLE BREEZY TODAY, WITH NORTHWEST WINDS GENERALLY IN THE 10-20MPH RANGE. LOOKS LIKE THE BOUNDARY LAYER WILL MIX TO ROUGHLY 3000-4000FT, AND WINDS UP AT THAT LEVEL ARE JUST A TAD STRONGER, SO NOT OUT OF THE QUESTION TO SEE A FEW GUSTS OVER 25 MPH. OF NOTE WILL BE THE CHILLY TEMPERATURES. 850MB TEMPERATURES ALOFT ARE ON THE ORDER OF -2C TO -4C, WHICH UNDER PERFECTLY SUNNY CONDITIONS WOULD SUPPORT HIGHS ONLY IN THE LOWER 50S. HOWEVER, GIVEN THE CLOUDS, WE`LL BE A LITTLE LOWER THAN THAT, AND SHOULD WORK OUT TO BE VERY SIMILAR TO YESTERDAY. THUS MID/UPPER 40S IN THE VALLEYS AND UPPER 30S TO LOWER 40S AT HIGHER ELEVATIONS. WITH THE COLD POOL ALOFT, WE WILL SEE A LITTLE BIT OF DESTABLIZATION THIS AFTERNOON, SO EXPECT SCATTERED SHOWERS TO DEVELOP, MAINLY ACROSS THE HIGHER TERRAIN OF VERMONT AND NORTHERN NEW YORK. ELEVATION WILL CONTROL WHETHER IT WILL BE RAIN OR SNOW. IN GENERAL, SNOW LEVELS THIS AFTERNOON WILL BE RUNNING ABOUT 1200 FEET. ACCUMULATIONS WILL BE VERY MINOR. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/... AS OF 350 AM EDT FRIDAY...THAT PESKY UPPER LOW WILL BE...WELL, PESKY...ALL THE WAY INTO SUNDAY. MODELS ALL SHOW THE CURRENT UPPER LOW OVER MAINE MOVING SOUTHEAST, HOWEVER ANOTHER LOW ROTATES IN TO TAKE IT`S PLACE. REGARDLESS OF WHAT IS HAPPENING ALOFT, THE NET RESULT FOR US ON THE GROUND WILL BE CONTINUED COOL, UNSETTLED CONDITIONS WITH RAIN/SNOW SHOWERS SCATTERED ABOUT. I THINK MOST OF THE SHOWERS WILL BE MORE CONFINED TO THE HIGHER TERRAIN, THANKS TO SOME OROGRAPHIC INFLUENCES FROM THE NORTHWESTERLY FLOW. INDICATIONS IN MODEL GUIDANCE THAT A LOW LEVEL BLOCKED FLOW WILL AGAIN DEVELOP LATER TONIGHT AND FIRST THING SATURDAY, SO PRECIPITATION MAY REFOCUS ITSELF A BIT MORE ALONG THE WEST SLOPES OF THE NORTHERN GREEN MOUNTAINS AT THAT TIME, THOUGH NOT EXPECTING HEAVY, SO JUST ANOTHER ROUND OF A DUSTING TO 1/2" OF SNOW. SHOULD BE ANOTHER SURGE OF DEEPER MOISTURE THAT ROTATES IN FROM THE NORTHEAST LATE SATURDAY NIGHT AND INTO SUNDAY MORNING. HAVE TRIED TO PAINT IN AN INCREASE OF POPS FROM NORTHERN VERMONT INITIALLY AND THEN SOUTHWARD ACROSS THE REGION DURING SUNDAY. STILL DON`T THINK IT WILL BE A VERY WIDESPREAD PRECIPITATION EVENT, JUST MORE IN THE WAY OF SCATTERED SHOWERS (RAIN & SNOW STILL DEPENDING ON ELEVATION). TEMPERATURES DO LOOK LIKE THEY WILL EVERY SO SLOWLY MODERATE EACH DAY AS THE FLOW ACROSS THE AREA TAKES ON MORE OF AN ATLANTIC OCEAN SOURCE, BUT STILL BE BELOW NORMAL. HUNG WITH A MIX OF GUIDANCE, SO LOOK FOR DAYTIME HIGHS IN THE 50S BOTH WEEKEND DAYS AND OVERNIGHT LOWS GENERALLY IN THE 30S. COLDER AT HIGHER ELEVATIONS. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 356 AM EDT FRIDAY...LATE WEEKEND/EARLY NEXT WEEK STILL INFLUENCED BY CLOSED UPPER LOW IN GULF OF MAINE SLOWLY EXITING EAST BY MID WEEK FOLLOWED BY PERHAPS ANOTHER TROUGH OR CUT OFF BY LATE NEXT WEEK. THE INFLUENCE OF CLOSED UPPER LOW DIMINISHES WITH TIME WITH BEST CHANCE OF RAIN SHOWERS BEING SUNDAY NIGHT THROUGH MONDAY-MONDAY NIGHT. COLD ENOUGH ALOFT THAT SOME SNOW SHOWERS POSSIBLE IN HIGHER ELEVATIONS AT NIGHT. SOME SHORT WAVE RIDGING TRYING TO SQUEEZE INTO THIS UGLY FLOW PATTERN FOR TUE-WED THEN MODELS DIFFER ON TIMING/STRENGTH OF NEXT POTENTIAL TROUGH/UPPER LOW FOR LATE NEXT WEEK. TEMPERATURES REMAIN COOLER THAN NORMAL (NORMAL U50S-L60S)THROUGH MON THEN NEAR NORMAL MID WEEK PERHAPS TURNING COOLER TOWARD END OF NEXT WEEK. MIN TEMPERATURES LARGELY 30S-L40S WITH UPPER 20S IN HIGHER ELEVATIONS. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... THROUGH 06Z SATURDAY...A VARIETY OF FLIGHT CATEGORIES IS EXPECTED OVERNIGHT WILL GRADUALLY IMPROVE TO VFR CONDITIONS FOR LATER FRIDAY MORNING AND AFTERNOON. WEST/NORTHWESTERLY HAS LEAD TO TERRAIN-DRIVEN RAIN AND SNOW SHOWERS...ESPECIALLY SLK/MPV AND WESTERN SLOPES JUST E OF BTV BUT ACTIVITY SHOULD DECREASE BY MORNING. NOT MUCH IMPACT EXPECTED AT BTV/PBG/MSS EXCEPT FOR A POSSIBLE LIGHT SHOWER...WITH VFR IN THE FORECAST. MPV/SLK WILL SEE PERIODS OF SNOW SHOWERS...WITH MVFR/IFR LIKELY. RUT EXPECTED TO SEE SOME LOWER CEILINGS (MVFR) AND A FEW SHOWERS NEARBY. LOWER CEILINGS/SHOWERS GRADUALLY DISSIPATE AND LIFT ON FRIDAY WITH ALL SITES VFR BY 16Z. SOME INSTABILITY SHOWERS MAY RETURN...MAINLY ACROSS MOUNTAINS AFT 21Z FRI. SURFACE WINDS GENERALLY ANTICIPATED TO BE OUT OF THE WEST FROM 5-15 KNOTS...WITH SOME GUSTS UP TO 20 KNOTS...MAINLY ON FRIDAY. OUTLOOK 06Z SATURDAY THROUGH TUESDAY... FOR THE ENTIRE PERIOD - VFR WITH PERIODS OF MVFR (AND POSSIBLY BRIEF IFR) IN SCATTERED RAIN SHOWERS DURING THE DAY AND RAIN/SNOW SHOWERS AT NIGHT. && .HYDROLOGY... UPDATED 1102 PM THURSDAY...THE FLOOD WARNING CONTINUES FOR THE BARTON RIVER NEAR COVENTRY. THE RIVER WENT ABOVE FLOOD STAGE EARLY THIS MORNING AND WENT UP QUICKLY...CRESTING AROUND 8.8 FEET THIS AFTERNOON. SINCE THEN...THE WATER LEVEL OF THE RIVER HAS BEGUN TO FALL...AND AT 11 PM IT WAS AT 8.4 FEET. EXPECT THIS TREND TO CONTINUE OVERNIGHT. CURRENTLY THE BARTON RIVER NEAR COVENTRY IS THE ONLY RIVER THAT WE EXPECT TO REACH FLOOD STAGE AS MOST OF THE OTHER RIVERS AND STREAMS HAVE CRESTED BELOW FLOOD STAGE. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...NASH NEAR TERM...NASH SHORT TERM...NASH LONG TERM...SLW AVIATION...MUCCILLI/SLW HYDROLOGY...TEAM BTV
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
129 AM EDT FRI APR 24 2015 .SYNOPSIS... A LARGE STORM SYSTEM WILL SLIDE NORTHEASTWARD OVERNIGHT THROUGH FRIDAY, KEEPING TEMPERATURES WELL BELOW NORMAL. SNOW SHOWER AND FLURRY ACTIVITY WILL DIMINISH AS DRIER AIR MOVES IN LATE TONIGHT AND FRIDAY, WITH IMPROVING CONDITIONS FOR SATURDAY WITH SUNSHINE EXPECTED. && .NEAR TERM /THROUGH TODAY/... WATER VAPOR IMAGERY SHOWS A LARGE UPPER LEVEL CYCLONE OVER NORTHERN NEW ENGLAND AND SOUTHERN QUEBEC THIS EVENING WHICH CONTINUES TO LEAD TO A COLD AND MOIST NORTHWEST FLOW OF AIR ACROSS CENTRAL NY AND NORTHEAST PA. 850 MB TEMPERATURES WERE VERY CHILLY FOR THIS TIME OF YEAR RUNNING AROUND -8C TO -10C AT THIS TIME. HRRR, RAP. WRF NMM, WRF ARW AND NAM12 ALL SHOW 850 MB TEMPS DROPPING TO -11C OR SO BY 12Z. LAKE ONTARIO AND ERIE WATER TEMPERATURES WERE ARND +1 TO 3C LEADING TO SOME LAKE ENHANCEMENT OF THE SYNOPTIC SCALE MOISTURE THAT WAS WRAPPING ARND THE UPPER LEVEL LOW. THIS WILL CONTINUE TO LEAD TO LATE SEASON SNOW SHOWERS AND FLURRIES OVERNIGHT. ONE SHORT WAVE WAS PASSING EAST OF OUR REGION AT THIS TIME SO THE RADAR COVERAGE OF THE SNOW SHOWERS AND FLURRIES HAS DIMINISHED AT THIS TIME. THE RAP SHOWS ANOTHER SHRT WAVE WILL PASS BY ARND 5-6Z WHICH SHUD RAMP SN SHOWER ACVTY UP A BIT...ESPECIALLY IN NC NY WHERE THERE WILL BE MORE LAKE MOISTURE ON A W-NW LL FLOW PATTERN. THE REST OF THE FORECAST AREA WILL REMAIN UNDER A STRATOCUMULUS DECK THROUGH THE NIGHT WITH A FEW FLURRIES AT TIMES. FOR FRIDAY...THE STRG LATE APRIL SUN WILL EVENTUALLY BREAK UP THE LAKE ENHANCED MOISTURE AND CLOUDS AND WE SHUD SEE SOME BREAKS BY AFTERNOON. OUR WRN AND SRN PARTS OF OUR FORECAST AREA LIKELY WILL BREAK OUT AND BECOME PC TO MS BY AFTERNOON. TEMPERATURES WILL REMAIN WELL BELOW NORMAL WITH SUB FREEZING TEMPERATURE MOST AREAS OVERNIGHT. THERE IS TOO MUCH WIND AND CLOUDS FOR ANY FROST AND OUR GROWING SEASON HAS NOT BEGUN YET SO NO MENTION OF FROST IN OUR ZONES FOR OVERNIGHT. && .SHORT TERM /TONIGHT THROUGH SUNDAY/... STACKED CYCLONE DRIFTS FROM MAINE TO OFF THE ATLANTIC COAST THIS PERIOD. AFTER WIDELY SCATTERED RAIN/SNOW SHOWER ACTIVITY DURING THE MORNING HOURS, ESPECIALLY OVER NERN FA, DRY NORTHWESTERLY FLOW SHOULD YIELD FAIR WEATHER FOR FRIDAY AFTERNOON AND SATURDAY. AFTER MAXES IN THE UPPER 30S TO MIDDLE 40S ON FRIDAY, BL-850MB TEMPS WILL REBOUND SEVERAL DEGREES CELSIUS FOR SATURDAY. GIVEN DRY ATMOSPHERE AND GOOD AMOUNT OF SUN, THINK MAX TEMPS WILL BOUNCE BACK INTO THE LOWER 50S IN MOST SPOTS, THOUGH THIS WILL STILL BE 8 TO 12 DEGREES BELOW NORMAL MAX TEMPS. A SURFACE LOW PRESSURE CENTER WILL SLIDE EASTWARD THROUGH VA/NC ON SUNDAY, WHILE A COOL RIDGE BUILDS SOUTH THROUGH THE GREAT LAKES INTO THE OHIO VALLEY. BELIEVE THE PRECIPITATION WILL REMAIN SOUTH AND WEST OF OUR FA, THOUGH A WEAK WAVE IN THE UPPER FLOW MAY SPAWN A SPRINKLE OR LIGHT SHOWER UP THE LAKE PLAIN. 330 AM EDT UPDATE... THE STACKED UPPR LOW WILL MOVE AS FAR EAST AS MAINE AND WE WILL REMAIN UNDER A NW FLOW ALOFT ON FRIDAY. THE CHANCE FOR SHOWERS WILL CONTINUE THRU FRIDAY AS WE WILL REMAIN WITHIN THE WRAP AROUND MOISTURE. THE CHANCE FOR SHOWERS ON SAT WILL BECOME LESS AS THE MOISTURE WITH THIS SYSTEM SHIFT SLIGHTLY FURTHER EAST AND THE LOW SHIFTS SLIGHTLY FURTHER EAST OFF THE EAST COAST. PRECIP TYPE WILL BE DEPENDENT ON SFC TEMPS... THUS SNOW POSSIBLE DURING THE OVERNIGHT HOURS AND RAIN DURING THE DAY TIME. NW FLOW ALOFT WILL REMAIN OVER THE REGION THRU THE FORECAST PERIOD AND CONTINUE TO SUPPORT COLDER THAN NORMAL TEMPS ACROSS THE REGION. TEMPS ON SAT WILL SLIGHTLY REBOUND INTO THE LOW TO UPPR 40S. AS THE UPPR LOW SHIFT EAST ON SAT... TEMPS WILL BE ABLE TO RISE INTO THE LOWER 50S OVER MUCH OF THE AREA. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... BOTH THE GFS AND EURO SHOW A DEEP AND VERTICALLY STACKED LOW WOBBLING OFF THE NE CST ON MON. NLY FLOW BHD THE FLOW WITH THE LWR UPR HGTS WILL KEEP ISLTD TO SCT SHOWRS OVER THE FCST AREA...ESP OVER THE NY ZONES...WITH BLO NRML DAYTIME TEMPS. IRONICALLY...THE EURO IS MORE PROGRESSIVE WITH THE SYSTEM AND SHOWS SOME IMPRVMT LTR TUE INTO THU WITH WEAK SFC RDGG AND A NARROW RDG ALOFT. GFS WANTS TO KEEP THE UPR LOW HANGING ARND AND IN FACT CAPTURES A SRN STREAM SYSTEM LATE IN THE PD TO ENHANCE THE UPR TROF. MODELS HAVE BEEN INCONSISTENT WITH THE FCST IN THE LONG TERM LDG TO A LOW CONFIDENCE FCST...NOT ALL THAT UNUSUAL THIS TIME OF YEAR. SO...CONTD WITH THE HPC GUID IDEA OF LOW CHANCE OR SLGT CHANCE POPS FOR MUCH OF THE LONG TERM...ESP IN THE NRN AND ERN ZONES. WITH THE NLY FLOW...TEMPS WILL REMAIN BLO NRML...ESP DURING THE DAY. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... 06Z FRI UPDATE... MAINLY UNRESTRICTED/VFR CONDS WILL BE WITH US FOR THE VALID TAF PD (THROUGH 06Z SAT). THE EXCEPTION COULD BE AROUND DAYBREAK (EITHER SIDE OF 12Z)...WHEN SCTD SNOW SHWRS/LWR CIG BASES COULD PROVIDE MVFR/FUEL ALT CONDS...WITH A LOWER PROBABILITY OF BRIEF IFR RESTRICTIONS AT KSYR/KITH/KBGM. NW SFC WINDS AROUND 10 KT EARLY THIS MRNG...WILL INCREASE AND BECOME GUSTY DURING THE LATE MRNG-AFTN HRS...BEFORE DIMINISHING AGN THIS EVE (AFTER 00Z SAT). .OUTLOOK... SAT-SUN...VFR. MON-TUE...OCNL -SHRA...WITH BRIEF MVFR RESTRICTIONS...MAINLY NY TERMINALS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJN/DJP NEAR TERM...DJN SHORT TERM...DJP LONG TERM...DGM AVIATION...DJN/MLJ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
752 PM EDT SAT APR 25 2015 .SYNOPSIS... A WARM FRONT WILL APPROACH FROM THE SOUTH AND WILL BE NEAR OR JUST NORTH OF THE AREA SUNDAY MORNING BEFORE GETTING SHOVED SOUTHWARD SUNDAY AFTERNOON AND EVENING. A SMALL RISK FOR STRONG TO SEVERE THUNDERSTORMS WILL REMAIN INTO SUNDAY. DRY HIGH PRESSURE WILL RETURN MONDAY INTO TUESDAY BEFORE A STORM SYSTEM IMPACTS THE AREA DURING THE MIDDLE OF NEXT WEEK. DRY HIGH PRESSURE IS EXPECTED TO RETURN BY FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 530 PM SATURDAY...BASED ON LATEST 88D RADAR MOSAIC TRENDS AND LATEST VIS AND IR SAT IMAGERY TRENDS AND LATEST 18Z VARIOUS MODEL RUNS...HAVE UPDATED EVENING AND OVERNIGHT POPS AND SKY CONDITIONS. BASICALLY LOWERING POPS TRENDS THIS EVENING AND OVERNIGHT TO LOW CHANCE/SLIGHT CHANCE/ISOLATED. IN ADDITION...HAVE SKY CONDITIONS IN THE CLOUDY/MOSTLY CLOUDY/VARIABLY CLOUDY TREND FOR THE EVENING THRU OVERNIGHT. IF SKIES PARTIALLY CLEAR ENOUGH...FOG COULD BECOME AN ISSUE DURING THE PRE-DAWN SUNDAY HOURS. PREVIOUS........................................................ AS OF 300 PM SATURDAY...SEVERE THREAT HAS BECOME REMOTE FOR THE DAYLIGHT HOURS. GUIDANCE AND OBSERVATIONS SHOW A STABLE ATMOSPHERE WITH A SHIELD OF LIGHT AND COOL STRATIFORM RAIN MOVING EAST ACROSS THE FORECAST AREA AND OUT TO SEA. AT THE SURFACE A DIFFUSE QUASI- STATIONARY FRONT IS WAVERING ABOUT WHILE A WARM FRONT MOVES UP FROM THE SOUTH. OVERALL SURFACE PATTERN IS NOT WELL DEFINED AND ALTHOUGH THERE ARE DIFFERENCES AMONG GUIDANCE THE GENERAL TREND IS TOWARDS WEAKER THAN ANTICIPATED CONVECTION AND SPARSER COVERAGE. NAM AND GFS MOS GUIDANCE HAVE SLIGHT CHANCE FOR OVERNIGHT POPS. CONSIDERING OTHER GUIDANCE ON HAND AND GENERAL UNCERTAINTY WILL KEEP IN SLIGHT CHANCE TO CHANCE POPS FOR THE OVERNIGHT PERIOD. BUFKIT AND OTHER DATA SHOW BETTER INSTABILITY SHOWING UP THIS EVENING AND OVERNIGHT SO MAKING CHARACTER OF PRECIP MORE CONVECTIVE IN NATURE AND WILL INCLUDE SLIGHT CHANCE FOR THUNDER. THE HRRR HAS BEEN VERY HELPFUL TODAY IN DEPICTING COVERAGE AND TRENDS SO WILL CONTINUE TO LEAN ON ITS GUIDANCE FOR THE NEAR TERM. THIS MODEL HAS ISOLATED TO SCATTERED SHOWERS FOR THE REMAINDER OF THE AFTERNOON WITH PERHAPS A MORE MODERATE LINE OF CONVECTION MOVING THROUGH AROUND MIDNIGHT. EXTENSIVE CLOUD COVER AND WARM FROPA WILL KEEP TEMPS OVERNIGHT ON THE MODERATE SIDE...IN VARIOUS SHADES OF THE 60S. THIS IS NOT MUCH DIFFERENT THAN TODAYS DAYTIME READINGS. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 300 PM SATURDAY...A WARM FRONT WILL BE SITUATED VERY NEAR OR JUST N OF THE AREA SUNDAY MORNING. MODEL PROFILES SHOW A DEEP WESTERLY FLOW WITH SIGNIFICANT MOISTURE RELEGATED TO THE LOWEST 3 KFT OR SO IN THE WARM SECTOR. A 50 KT JET WILL BE LOCATED 3-5 KFT AGL SUNDAY. THE GFS SHOWS LITTLE IN THE WAY OF INSTABILITY ON SUN WHILE THE NAM PORTRAYS MIXED LAYER CAPE VALUES UP TO AROUND 1500 J/KG AND THIS SEEMS MUCH MORE REASONABLE. THE INSTABILITY WILL BE SHRINKING SOUTHWARD WITH TIME AS THE LAST OF THE WEAK WAVES OF LOW PRESSURE MOVES OFFSHORE TO CONSOLIDATE AND STRENGTHEN WELL OFF THE NC COAST. MODEL SOUNDINGS ACTUALLY SHOW A STRONG FRONTAL INVERSION DEVELOPING FROM N TO S...LASTLY ACROSS THE SOUTHERN GRAND STRAND AND SOUTH SANTEE RIVER AREAS BY MID AFTERNOON SUN. CONFIDENCE IN TIMING IS NOT HIGH...BUT TRENDS LOOK TO BE ON THE RIGHT TRACK. GIVEN MAGNITUDE OF DRY AIR IN STRONG AND DEEPENING WESTERLY FLOW ALOFT...WOULD EXPECT COVERAGE OF CONVECTION TO BE ISOLATED TO SCATTERED. CAN NOT RULE OUT AN ISOLATED STRONG OR SEVERE THUNDERSTORM TO INCLUDE HAIL AND/OR STRONG TO DAMAGING WIND GUSTS. THE SEVERE WEATHER RISK WILL BE PRIMARILY ACROSS THE SOUTHERN REACHES OF OUR FORECAST AREA...WHERE INSTABILITY WILL BE GREATEST...AS WELL AS PERHAPS WHERE SEABREEZE INTERACTS WITH THE FRONT. ANY SEVERE WEATHER WILL INCLUDE STRONG TO DAMAGING WIND GUSTS WILL SHOW POPS TRENDING LOWER FROM N TO S LATE IN THE AFTERNOON AND THROUGH THE EVE HOURS. A SERIES OF SHORTWAVE TROUGHS ROUNDING A RETROGRADING AN UPPER LOW OFF THE NEW ENGLAND COAST WILL HELP TO REINFORCE THE COOLER AND DRIER AIR ADVECTING INTO THE FORECAST AREA MON AND MON NIGHT. A GOOD DEAL OF SUNSHINE MON WILL BE BATTLING THE COOL NW FLOW WITH 850 MB TEMPS DROPPING TO AROUND 3 DEG C. HIGHS SUN WILL LIKELY VARY FROM N TO S AND DEPENDING ON CLOUD COVER...THERE COULD BE A SIGNIFICANT TEMP GRADIENT ACROSS THE AREA. WILL FORECAST LOWER TO MID 80S ACROSS THE SOUTH SANTEE RIVER AREA WITH MID AND UPPER 70S ELSEWHERE. HOWEVER...THE NORTHERN REACHES OF THE AREA COULD BE STYMIED IN THE LOWER 70S GIVEN THEIR PROXIMITY TO THE BOUNDARY AND GREATER CLOUD COVER. HIGHS ON SUN WILL BE IN THE LOWER 70S FOR THE MOST PART...ONE TO TWO CATEGORIES BELOW NORMAL FOR THE WANING DAYS OF APRIL. AFTERNOON RELATIVE HUMIDITY LEVELS WILL BE FALLING THROUGH THE 40S AND 30S ON MON AS DRY AND COOL HIGH PRESSURE TO THE NW BUILDS INTO THE EASTERN CAROLINAS. THE COOLEST NIGHT...MON NIGHT...WILL BE IN THE MID AND UPPER 40S. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 300 PM SATURDAY....MEDIUM RANGE GUIDANCE CONTINUES TO STRUGGLE WITH THE EVOLUTION OF A MID LEVEL SYSTEM THAT WILL AFFECT THE AREA TO SOME EXTENT FOR MIDWEEK. SEVERAL MODELS KEEP THE TROUGH MORE PROGRESSIVE WHILE OTHERS PHASE THE SYSTEM WITH NORTHERN STREAM ENERGY CREATING A MORE DYNAMIC SYSTEM AND PROLIFIC RAIN MAKER FOR OUR AREA. UNTIL THE MODELS CONVERGE ON A DEPENDABLE SOLUTION...PRUDENCE CALLS FOR KEEPING POPS IN THE FORECAST FROM LATE TUESDAY THROUGH THURSDAY. NO CHANGES TO TEMPERATURE FORECAST WHICH WILL BE A LITTLE BELOW CLIMATOLOGY. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... AS OF 00Z...THE WARM FRONT HAS MOVED TO NEAR A KLBT TO NORTH OF KILM LINE EARLY THIS EVENING. SOME CLEARING OF LOW CLOUDS FROM THE SW-W SUGGESTS MVFR CIGS MAY DECREASE EARLY THIS EVENING LEAVING VFR CONDITIONS. SHOWERS SHOULD BE AT A MINIMUM THIS EVENING AND OVERNIGHT...BUT WILL NEED TO MONITOR SHOWERS AND THUNDERSTORMS MOVING ENE FROM GEORGIA. THUNDERSTORMS SHOULD STAY SOUTH OF THE TERMINALS BUT SOME LIGHT SHOWERS COULD STILL SPREAD ACROSS THE TERMINALS 04-07Z AS THE ACTIVITY DISSIPATES. SKIES CLEAR AND WINDS BECOME LIGHT SW AFTER MIDNIGHT. VSBYS SHOULD BEGIN TO DECREASE WITH IFR VSBYS AND TEMPO IFR CIGS POSSIBLE. CONFIDENCE OF OCCURRENCE IS MODERATE BUT THERE IS VERY LOW CONFIDENCE IN TIMING AND DURATION. A COLD FRONT WILL MOVE THROUGH THE NORTHERN TERMINALS DURING THE EARLY MORNING AND DURING THE AFTERNOON AT THE SOUTHERN TERMINALS WITH WINDS SHIFTING TO THE NW-N. GOOD CHANCE OF IFR CIGS BECOMING MVFR AT KILM/KLBT DURING THE MORNING...WITH MVFR CIGS AT THE REMAINING TERMINALS. SHOWERS POSSIBLE DURING THE DAY WITH ISOLATED THUNDERSTORMS AT THE SOUTHERNMOST TERMINALS. EXTENDED OUTLOOK...VFR MONDAY AND TUESDAY. SHOWERS POSSIBLE WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 530 PM SATURDAY...LATEST MODEL RUNS NOT ALL THAT CONVINCING ENOUGH TO CHANGE THE CURRENT FORECAST WINDS AND SIGNIFICANT SEAS TRENDS FOR THIS EVENING AND OVERNIGHT. WILL HOLD ONTO WHAT IS CURRENTLY ADVERTISED...INCLUDING HOLDING OUT WITH THE ISSUANCE OF A POSSIBLE SCEC. PREVIOUS................................................... AS OF 300 PM SATURDAY...SOUTH WINDS THIS AFTERNOON WILL BECOME SW TONIGHT AS A WARM FRONT MOVES NORTH ACROSS THE WATERS. WINDS WILL STAY IN THE GENERAL 10 TO 15 KT RANGE WITH 2 TO 4 FT OF SEAS FOR MOST OF THE PERIOD. HOWEVER...THERE MAY BE A BRIEF PERIOD OF HIGHER WINDS AND SEAS TONIGHT AS THE WARM FRONT APPROACHES THE WATERS. IF SO...EXERCISE CAUTION HEADLINES MAY BE NEEDED. SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 300 PM SATURDAY...THE WIND DIRECTION WILL BE FROM THE W OR SW SUN MORNING...THEN VEER TO THE NW AND N AS A FRONT SINKS BACK TO THE S THROUGH THE DAY. THE FRONT MAY NOT MOVE S OF THE SOUTHERNMOST WATERS TIL LATE AFTERNOON. THERE WILL BE A MODEST SURGE SUN NIGHT AND THEN A SLIGHTLY STRONGER ONE MON NIGHT AS A SERIES OF SHORTWAVE TROUGHS ROTATE AROUND UPPER LOW RETROGRADING OFF THE NEW ENGLAND COAST. WINDS WILL BE STRONGEST WHEN THE WIND DIRECTION IS FROM THE N OR NNW...UP TO 15 TO 20 KT MON NIGHT. SEAS WILL BE 2 TO 4 FT MOST OF THE TIME. HOWEVER...EXPECT SEAS TO BUILD UP TO 5 FT DURING THE SURGES...WITH THE GREATEST COVERAGE OF 5 FT SEAS MON NIGHT. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 300 PM SATURDAY...DESPITE AN INTERESTING AND POSSIBLY DYNAMIC SYNOPTIC WEATHER SCENARIO AT THE MID LEVELS...THE SURFACE FEATURES DRIVING THE WINDS AND SEAS WILL BE RATHER BENIGN IN COMPARISON. HIGH PRESSURE TO THE NORTH WILL MAINTAIN A NORTH TO NORTHEASTERLY FLOW ACROSS THE WATERS THROUGH WEDNESDAY WITH SPEEDS GENERALLY TEN KNOTS OR LESS. FORECAST CHALLENGE THEN ARISES AS MODELS ARE STILL UNSURE HOW TO HANDLE LOW PRESSURE IN THE GULF OR UP THE EAST COAST BOTH IN A PLACEMENT AND STRENGTH PERSPECTIVE. WILL MAINTAIN THE MODEST OFFSHORE FLOW FOR THURSDAY DUE TO UNCERTAINTY. SIGNIFICANT SEAS WILL BE 2-4 FEET. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...DCH/REK SHORT TERM...JDW LONG TERM...SHK AVIATION...MRR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1019 PM CDT SAT APR 25 2015 .UPDATE... ISSUED AT 1020 PM CDT SAT APR 25 2015 FORECAST CHALLENGE WILL BE OVERNIGHT LOWS. LATEST RUC GUIDANCE DOING WELL WITH INHERITED MINIMUM TEMP FCST SO HAVE USED RUC FOR GUIDANCE ON WIND AND HOURLY TEMPS. ADJUSTMENTS TO SKY MADE AT 7 PM WORKED OUT WELL SO NO FURTHER CHANGES EXPECTED. UPDATE ISSUED AT 655 PM CDT SAT APR 25 2015 FORECAST UPDATE WILL ADDRESS MINOR SKY ISSUES...WITH EASTERN NORTH DAKOTA CLEARING OUT A BIT MORE RAPIDLY THAN PREV FCST INDICATED. WITH MID LVL DECK WELL OFF TO WEST...WILL DECREASE SKY OVER ERN ND THROUGH THE NIGHT. NO OTHER CHANGES MADE AT THIS TIME. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 302 PM CDT SAT APR 25 2015 TEMPERATURES AND CLOUD COVER WILL BE THE MAIN CONCERNS FOR THE PERIOD. CLOUDS HAVE MOVED MOSTLY WEST OF THE RED RIVER AS DRIER AIR HAS BEEN COMING IN FROM THE EAST UNDER HIGH PRESSURE. THERE HAVE BEEN SOME CU REDEVELOPMENT IN THE CENTRAL RED RIVER VALLEY...BUT FOR THE MOST PART THE MINNESOTA SIDE HAS BECOME PARTLY CLOUDY WITH SOUTHEASTERN NORTH DAKOTA STILL SOCKED IN WITH STRATUS. THE RAP 925-850MB RH FIELD HAS BEEN DOING DECENT WITH THE CLOUD COVER...AND IT HAS THE HIGHER RH VALUES SLOWLY MOVING WEST THROUGH TONIGHT. THERE WILL ALSO BE SOME HIGHER CLOUDS COMING IN THROUGH WESTERN ND AS A SHORTWAVE TROUGH MOVES INTO THE CANADIAN ROCKIES. THINK THE CLOUDS AND WINDS AROUND 10 KTS WILL KEEP TEMPS IN THE WESTERN COUNTIES IN THE 40S WHILE THE EAST WILL HAVE LIGHT WINDS AND CLEAR SKIES...DROPPING DOWN BELOW FREEZING TONIGHT. THE DRY AIR WILL CONTINUE TO COME IN AS HIGH PRESSURE REMAINS ANCHORED TO OUR NORTHEAST. THE MODELS SHOW A WEAK TROUGH OF LOW PRESSURE ENTERING CENTRAL ND...BUT ALL HAVE THE PRECIP ALONG THAT BOUNDARY DISSIPATING AS IT MOVES EAST. THIS SEEMS REASONABLE GIVE THE DRY ENVIRONMENT AND NOT MUCH UPPER FORCING...SO WILL KEEP POPS OUT UNTIL AFTER 00Z MONDAY. TEMPS ON SUNDAY WILL BE A BIT WARMER THAN TODAY WITH HIGHER CLOUDS AND A SLIGHTLY WARMER AIR MASS. KEPT READINGS IN THE 60S. SUNDAY NIGHT...THE NORTHERN BRANCH SHORTWAVE TROUGH WILL PROGRESS INTO SASKATCHEWAN/MANITOBA...WITH THE WEAK TROUGH AXIS MOVING INTO THE FAR WESTERN CWA. THERE WILL BE SOME IMPROVING UPPER LEVEL SUPPORT AS THE SYSTEM MOVES EAST...BUT IT WILL BE FIGHTING AGAINST CONTINUED DRY AIR COMING IN FROM THE SFC HIGH TO THE EAST. INCLUDED SOME SHOWERS GETTING INTO OUR FAR NORTHWESTERN CWA AFTER MIDNIGHT...BUT THINK THAT THE BULK OF PRECIP WILL HOLD OFF UNTIL MONDAY. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 302 PM CDT SAT APR 25 2015 MONDAY THROUGH TUESDAY...SPLIT FLOW CONTINUES OVER NORTH AMERICA WITH THE NORTHERN BRANCH SHORTWAVE MOVING THROUGH SOUTHERN CANADA TO OUR NORTH. THIS WILL PUSH A WEAK SFC TROUGH AXIS INTO THE CWA MONDAY AND MONDAY NIGHT...WITH SOME GOOD Q VECTOR CONVERGENCE FOR RISING MOTION. WILL CONTINUE TO KEEP POPS HIGH THROUGH MONDAY AND MONDAY NIGHT ALONG THE SFC TROUGH AXIS...WITH MAINLY LIGHT RAIN SHOWERS EXPECTED. LEANED TOWARDS THE DRIER GFS/NAM RATHER THAN THE WETTER INTERNATIONAL MODELS GIVEN THE TENDENCY LATELY FOR OVERDOING RAIN. WE SHOULD DRY OUT BY TUESDAY AS THE SFC TROUGH MOVES OFF TO THE EAST. HIGHS ON MONDAY WILL BE IN THE 60S IN MOST OF THE CWA BUT THE NORTHWESTERN COUNTIES COULD STAY IN THE 50S WITH RAIN COMING IN EARLIER. MONDAY NIGHT WILL RANGE FROM THE UPPER 30S TO LOW 40S AND TUESDAY SHOULD BE IN THE 60S ACROSS THE REGION. TUESDAY NIGHT THROUGH FRIDAY...MODELS SHOW A BUILDING UPPER RIDGE THROUGH THE REST OF THE PERIOD. GEM NOT SHOWING AS STRONG A RIDGE AS THE OUTLIER...SO FAVORED AN ECMWF/GFS BLEND FOR THIS FORECAST. THUS...EXPECT TEMPERATURES TO BE ON THE WARMER SIDE...WITH HIGHS POSSIBLY REACHING CLOSE TO THE MID 70S. OTHERWISE...THE PERIOD WILL REMAIN ON THE DRY SIDE. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 655 PM CDT SAT APR 25 2015 VFR CONDS EXPECTED WITH EAST TO SOUTHEAST FLOW THROUGH TOMORROW EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...SPEICHER SHORT TERM...JR LONG TERM...JR/HOPKINS AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1145 PM CDT THU APR 23 2015 .UPDATE... ISSUED AT 1145 PM CDT THU APR 23 2015 QUICK UPDATE TO INCLUDE THUNDERSTORMS IN THE FORECAST. THERE IS SOME MID-LEVEL INSTABILITY THIS EVENING PER THE 00 UTC BISMARCK SOUNDING. A LOW LEVEL JET HAS KICKED IN PROVIDED ENOUGH LIFT FOR CONVECTION TO OCCUR AND SPARK A FEW ISOLATED THUNDERSTORMS. REST OF THE FORECAST IS ON TRACK WITH SHOWERS/THUNDERSTORMS CONTINUING ACROSS THE JAMES VALLEY THROUGH THIS MORNING. UPDATE ISSUED AT 938 PM CDT THU APR 23 2015 TRENDED THE POPS EAST WITH THE RADAR RETURNS. HRRR MODEL CONTINUES TO DEVELOP SHOWERS OVER THE JAMES RIVER VALLEY IN LOW LEVEL WARM ADVECTION THROUGH TONIGHT. CLEARING WEST. UPDATE ISSUED AT 724 PM CDT THU APR 23 2015 UPDATE FOR POPS AND CLOUDS MAINLY. SURFACE LOW PRESSURE IDENTIFIED BY RUC MODEL CENTERED NEAR THE BLACK HILLS WITH A SOUTHEAST TO EASTERLY WIND COMPONENT ACROSS ALL OF NORTH DAKOTA. THIS WILL MAINTAIN FAVORABLE SHEAR AND MAY SUPPORT MAINTAINING THE LIMITED MOISTURE ACROSS THE JAMES RIVER VALLEY TONIGHT. SHOWERS EXPECTED TO DEVELOP AND REMAIN IN THE JAMES RIVER VALLEY TONIGHT. UPDATE ISSUED AT 503 PM CDT THU APR 23 2015 GETTING REPORTS OF SNOW FROM STANLEY AND PARSHALL AREAS. LOOKS LIKE COOLING TO THE WET BULB IS CREATING ENOUGH COOLING FOR SNOW LATE THIS AFTERNOON. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 303 PM CDT THU APR 23 2015 SHOWERS THIS AFTERNOON THROUGH TONIGHT HIGHLIGHT THE SHORT TERM FORECAST. OUTSIDE OF THE HIGHWAY 200 CORRIDOR...THE MAJORITY OF PRECIPITATION IS NOT REACHING THE GROUND DUE TO DRY AIR IN THE SUB-800 MB LAYER. THE 16-18 UTC HRRR ITERATIONS HAVE THE BEST HANDLING OF THE ONGOING PRECIPITATION...ESPECIALLY THAT WHICH IS REACHING THE GROUND...AND WILL WEIGH HEAVILY ON THEIR SOLUTIONS THROUGH AFTERNOON AND EVENING. THEREAFTER...THE 12 AND INCOMING 18 UTC GLOBAL AND HIGH RESOLUTION SUITES ARE IN AGREEMENT ON ELEVATED SHOWERS DEVELOPING TONIGHT ACROSS THE JAMES AND INTO THE RED RIVER VALLEYS BY 05 UTC WITH A MODEST LOW LEVEL JET AHEAD OF THE SURFACE LOW ACROSS WESTERN SOUTH DAKOTA. GIVEN MARGINALLY POSITIVE SHOWALTER VALUES...WILL NOT PUT IN THUNDER AT THIS TIME. FRIDAY APPEARS TO BE DRY ACROSS WESTERN AND CENTRAL NORTH DAKOTA BETWEEN THE STRONGER LOW ACROSS THE CENTRAL PLAINS AND THE PACIFIC NORTHWEST TROUGH. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 303 PM CDT THU APR 23 2015 A SPLIT FLOW THROUGH THE WEEKEND WITH PERIODS OF INTERACTION BETWEEN THE SOUTHERN STREAM AND NORTHERN STREAM. THIS WILL ULTIMATELY SET UP AN INCREASINGLY WET/UNSETTLED WEATHER PATTERN THROUGH EARLY NEXT WEEK. TWO MAIN SHORTWAVES TO PUSH ACROSS WESTERN AND CENTRAL NORTH DAKOTA FRIDAY NIGHT THROUGH MONDAY. THE LATEST ECMWF IS ADVERTISING A MORE CONTINUOUS RAIN OVER THE WEEKEND INTO MONDAY...WHILE THE GFS/CANADIAN GEM HAS A MORE DISTINCT START/END TIME WITH EACH WAVE. UTILIZED A BLEND OF THE ABOVE MODELS ABOVE. EXPECT A BRIEF DRYING AND WARMING TREND BY MIDWEEK...THEN A PROGRESSIVE AND POSSIBLY UNSETTLED WEATHER PATTERN SETTING UP LATE IN THE EXTENDED. FOR FRIDAY NIGHT THROUGH SATURDAY...A TRANSITORY 700MB-500MB RIDGE DEVELOPS OUT AHEAD OF AN APPROACHING SHORTWAVE TROUGH SLIDING INTO THE NORTHERN ROCKIES. THIS SHOULD KEEP CONDITIONS DRY FOR MOST AREAS FRIDAY NIGHT BEFORE EAST TO SOUTHEAST WINDS ADVECT AN AREA OF MOISTURE INTO THE WEST. THIS MOISTURE WILL CONVERGE INTO AN APPROACHING SURFACE COLD FRONT IN EASTERN MONTANA. THUS POPS BECOME LIKELY THEN CATEGORICAL SATURDAY IN THE WEST...WITH DRIER CONDITIONS IN THE EAST AS MID LEVEL RIDGING REMAINS INTACT UNTIL 00Z SUNDAY. SATURDAY NIGHT THROUGH MONDAY NIGHT...AS MENTIONED ABOVE THERE ARE DIFFERENCES IN THE ECMWF AND GFS/GEM...ESPECIALLY SATURDAY NIGHT THROUGH SUNDAY. PER GFS/GEM...THE SURFACE LOW/COLD FRONT AND SHORTWAVE MOVE INTO SOUTHERN CANADA WITH SHOWERS DIMINISHING SATURDAY NIGHT INTO SUNDAY. THE TRAILING COLD FRONT STALLS UNDER A SOUTHWEST FLOW ALOFT...WITH LOW LEVEL SOUTH TO SOUTHEAST WINDS FEEDING MOISTURE INTO NORTH DAKOTA. THE GFS/GEM MODELS TREND TOWARD A CESSATION TO THE PRECIPITATION UNTIL SUNDAY NIGHT WHEN THE THE FRONT BECOMES RE-ENERGIZED AS THE NEXT SHORTWAVE TROUGH APPROACHES. WITH THE SURFACE COLD FRONT AND SOUTHERN STREAM MOISTURE ALREADY IN PLACE...THIS SETS THE STAGE FOR A MORE WIDESPREAD PRECIPITATION EVENT SUNDAY NIGHT THROUGH MONDAY. AS MENTIONED ABOVE THE LATEST ECMWF REALLY DOES NOT STOP THE PRECIPITATION WITH THE INITIAL SHORTWAVE...RATHER KEEPS THE SURGE MAINLY CONTINUOUS IN THE WEST AND SLOWLY SPREADS IT EAST AND NORTH THROUGH MONDAY. TOTAL PRECIPITATION AMOUNTS COULD RANGE BETWEEN A HALF INCH TO ONE INCH IN THE WEST TO AROUND A QUARTER OF AN INCH IN CENTRAL NORTH DAKOTA THROUGH MONDAY NIGHT. MONDAY NIGHT THROUGH THURSDAY...GOOD AGREEMENT THAT PRECIPITATION WILL BE EAST OF THE JAMES RIVER VALLEY BY 12Z TUESDAY FOLLOWED BY UPPER RIDGING TUESDAY AND WEDNESDAY. WARM AIR ADVECTION RAMPS UP LATE TUESDAY INTO WEDNESDAY...AHEAD OF AN ADVANCING COLD FRONT WHICH IS FORECAST TO CROSS SOUTHERN CANADA WEDNESDAY AFTERNOON/EVENING. THE GFS SHOWS SOME LIGHT PRECIPITATION DEVELOPING IN THE NORTH BEHIND THE FRONT WEDNESDAY AFTERNOON. THE ECMWF IS ABOUT 6HRS SLOWER WITH THE COLD FRONT...NOT ARRIVING INTO THE NORTHWEST UNTIL AROUND 00Z THURSDAY. THURSDAY LOOKS DRY...ALTHOUGH THIS MAY BE BRIEF AS THE NEXT SYSTEM IS ALREADY APPROACHING THURSDAY NIGHT INTO FRIDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1145 PM CDT THU APR 23 2015 VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THE TAF PERIOD. VCTS POSSIBLE NEAR JAMESTOWN AROUND 06Z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AJ SHORT TERM...AYD LONG TERM...KS AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1136 PM CDT THU APR 23 2015 .UPDATE... ISSUED AT 1140 PM CDT THU APR 23 2015 NO CHANGES NEEDED FOR THIS UPDATE. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 321 PM CDT THU APR 23 2015 PRECIP CHANCES AND TYPE TONIGHT AND TOMORROW WILL BE THE MAIN FORECAST ISSUE FOR THE SHORT TERM. WEST TO SOUTHWEST FLOW CONTINUES OVER THE REGION WITH VARIOUS WEAK SHORTWAVES MOVING THROUGH THE FLOW. ONE WEAK LEAD SHORTWAVE HAS ALREADY BEEN HEADING TOWARDS WESTERN ND...WITH SOME DECENT RADAR RETURNS OVER THAT PART OF THE STATE. SOME LIGHT RAIN HAS BEEN REACHING THE GROUND...ALTHOUGH NOT AS MUCH AS RADAR WOULD INDICATE. DEW POINTS OVER THE CWA HAVE BEEN IN THE SINGLE DIGITS TO TEENS. THE RAP AND HRRR HAVE THE PRECIP DISSIPATING AS IT MOVES EAST...WHICH SEEMS REASONABLE GIVEN THE VERY DRY AIR. THINK THE BETTER SHOT FOR PRECIPITATION WILL BE LATER TONIGHT AS A MORE SOUTHERN SHORTWAVE MOVES INTO WY AND SFC LOW PRESSURE DEVELOPS OVER WESTERN SD. THERE WILL BE SOME MID LEVEL WARM AIR ADVECTION/FRONTOGENESIS OVER MAINLY THE SOUTHERN COUNTIES TONIGHT. SOME OF THE MODELS HAVE SEVERAL TENTHS OF QPF TONIGHT...BUT GIVEN HOW LONG IT WILL TAKE TO SATURATE WILL LEAN TOWARDS THE LOWER END FOR PRECIP AMOUNTS. MODEL SOUNDINGS SHOW MOSTLY ABOVE ZERO AS THE COLUMN SATURATES...BUT SOME SNOW MIXING IN ON THE NORTHERN EDGE OF THE PRECIP IS NOT OUT OF THE QUESTION. TOMORROW...THE SHORTWAVE TROUGH MOVES OUT INTO THE PLAINS...AND THERE SHOULD BE A DECENT AMOUNT OF PRECIP OVER THE SOUTHERN COUNTIES SPREADING NORTH AND EAST AS THE BEST MID LEVEL BAROCLINIC ZONE LIFTS ACROSS THE AREA. CONTINUED TO KEEP LIKELY POPS FOR A RAIN/SNOW MIX OVER THE SOUTHEASTERN COUNTIES FOR FRIDAY MORNING...LINGERING INTO THE AFTERNOON. THE CLOUDS AND PRECIP SHOULD KEEP TEMPS IN THE LOWER 40S IN THE EAST...BUT THINK THERE WILL BE ENOUGH PEAKS OF SUN TO GET ABOVE 50 IN THE WESTERN COUNTIES WHERE IT WILL BE DRIER. PRECIP WILL BEGIN TO TAPER OFF FRIDAY NIGHT BUT KEPT SOME LOWER POPS THROUGH SATURDAY MORNING IN OUR SOUTHEAST TO COORDINATE WITH NEIGHBORS. CLOUDS AND INCREASING EASTERLY WINDS WILL KEEP TEMPS IN THE 30S FRIDAY NIGHT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 321 PM CDT THU APR 23 2015 SATURDAY AND SUNDAY...UPPER RIDGING WILL BUILD IN BRIEFLY...BUT GIVE WAY AS THE NEXT SPLIT TROUGH BEGINS TO MOVE OUT FROM THE WESTERN CONUS BY LATE SUNDAY. SFC HIGH PRESSURE OVER ONTARIO SATURDAY WILL BRING EAST TO SOUTHEASTERLY WINDS WITH DRIER AIR INTO THE CWA AND HIGHS SHOULD REACH THE 50S WITH AT LEAST SOME BREAKS IN THE CLOUDS. TEMPS WILL BE EVEN WARMER FOR SUNDAY AS THE SFC HIGH MOVES OFF TO THE EAST AND A TROUGH DEVELOPING OVER THE WESTERN PLAINS STARTS SOME WARMER AIR MOVING BACK TO THE NORTH. THE ECMWF TRIES TO BRING SOME PRECIP INTO OUR WESTERN COUNTIES FOR SUNDAY AS THE NEXT UPPER SYSTEM APPROACHES...BUT THE OTHER MODELS ARE A BIT SLOWER. INCLUDED SOME LOW POPS IN THE DEVILS LAKE BASIN BUT THINK THE MAIN PRECIP WILL HOLD OFF UNTIL AFTER 00Z MONDAY. SUNDAY NIGHT THROUGH THURSDAY...LONG WAVE UPPER LEVEL LOW PRESSURE THAT WAS NORTH OF THE GREAT LAKES WILL MOVE OFF THE NEW ENGLAND STATES EARLY IN THE PERIOD. BUT LONG WAVE TROUGH BECOMES RE- ESTABLISHED OVER THE NORTHEAST STATES BY THE END OF THE PERIOD. LONG WAVE UPPER RIDGE BUILDS OVER THE US AND CANADIAN ROCKIES THIS PERIOD. ECMWF AND GFS WERE TRENDING FASTER THEN SLOWER OVER THE LAST COUPLE MODEL RUNS. THE GFS IS FASTER THAN THE ECMWF. SO WILL PREFER THE SLOWER ECMWF. KEPT POPS FROM PREVIOUS RUN FOR MON NIGHT THROUGH TUE NIGHT. APPROACHING UPPER LEVEL TROUGH WILL PRODUCE PRECIP FOR MON AND TUE AND ANOTHER SHORT WAVE TROUGH IS EXPECTED WED NIGHT THROUGH THU NIGHT. HIGH TEMPS WERE INCREASED TWO TO FIVE DEGREES FOR MON TUE AND WED. HIGH TEMPS DECREASED TWO TO FIVE DEGREES FOR THU FROM THIS MORNINGS FORECAST PACKAGE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1140 PM CDT THU APR 23 2015 EXPECT VFR CIGS TO LOWER INTO MVFR RANGE LATE TONIGHT OR FRI...AS LOW LEVEL MOISTURE INCREASES. THERE COULD BE A FEW SHOWERS MAINLY IN THE SOUTH AND EAST. WINDS SHOULD BE FROM THE E/SE AND COULD GUST OVER 20KT ON FRI. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...DK SHORT TERM...JR LONG TERM...JR/HOPPES AVIATION...DK
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1135 PM EDT SAT APR 25 2015 .SYNOPSIS... WEAKENING LOW PRESSURE WILL TRACK SOUTH OF PENNSYLVANIA TONIGHT. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE STATE ON SUNDAY. A PERSISTENT UPPER LEVEL TROUGH OVER THE NORTHEASTERN UNITED STATES WILL FAVOR UNSEASONABLY COOL TEMPERATURES THROUGH THE END OF THE MONTH. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... WEAKENING SHORTWAVE SLIPPING SOUTH OF PA THIS EVENING. RADAR TRENDS AND HRRR SUGGEST DWINDLING BAND OF RAIN ASSOC WITH FGEN FORCING IN THE 8-7H LYR WILL ONLY JUST GRAZE SOUTHERN SOMERSET/BEDFORD COUNTIES THIS EVENING. SOME SNOW EVEN REPORTED AT GARRETT CO AIRPORT...BUT PRECIP RTS/EVAP COOLING PROBABLY WON/T BE SIG ENOUGH TO PRODUCE ANY SNOW IN PA. NORTHERLY FLOW WILL ADVECT DRIER AIR INTO THE REGION LATER TONIGHT...ENDING THE THREAT OF RAIN ALONG THE S TIER AND BRINGING CLEARING SKIES TO THE NORTHERN COUNTIES. BLEND OF LATEST LAMP/RAP OUTPUT SUPPORTS OVERNIGHT LOWS FROM THE U20S ACROSS THE N MTNS...TO THE U30S ACROSS THE LOW ELEVATIONS ALONG THE MD BORDER. HAVE ADDED FROST TO THE FCST ACROSS THE NORTHERN HALF OF THE STATE...WHERE SKIES ARE LIKELY TO BECOME MCLEAR OVERNIGHT. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... NARROW SFC RIDGE AND ASSOC BAND OF DRY AIR/LOW PWATS OVR UPSTATE NY THIS EVENING WILL SLIDE SOUTH INTO CENTRAL PA SUNDAY MORNING. THUS...SEE A MAINLY SUNNY START TO THE DAY. HOWEVER...UPPER TROF AND ASSOC COOL TEMPS ALOFT WILL BE SWINGING SOUTH INTO THE STATE BY AFTN. THUS...EXPECT PLENTY OF AFTN CU AND EVEN A FEW ISOLD -SHRA...ESP OVR THE N MTNS. GIVEN THE EXPECTED SPARSITY OF COVERAGE AND LOW PWATS EXPECT MEASURABLE RAINFALL TO BE A VERY LOW PROBABILITY. THUS...WILL NOT EXPLICITLY MENTION -SHRA IN FCST ATTM. 18Z GEFS MEAN 8H TEMPS SUPPORT MAX TEMPS FROM NR 50F ACROSS THE NW MTNS...TO NR 60F ACROSS THE LOWER SUSQ VALLEY...STILL WELL BLW NORMAL FOR LATE APRIL. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... ACTIVE NORTHERN AND SOUTHERN STREAM SPLIT FLOW PATTERN ACROSS NORTH AMERICA WILL KEEP THE REGION IN UPPER LEVEL TROFFINESS THROUGH MUCH OF THE PERIOD. THE BLOCKED UP NRN STREAM...GENERALLY NW FLOW PATTERN OVER THE NORTHEAST WILL TEND TO SHUNT SRN STREAM SYSTEM TO THE SOUTH OF PA. EARLY NEXT WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...THIS LOW FINALLY LIFTS OUT FOR GOOD..BUT DIGGING TROUGH FROM UPPER MIDWEST WILL EXTEND INTO THE SOUTHEAST U.S. BY LATE WEEK...COMBINED WITH A SOUTHERN STREAM SHORTWAVE LIFTING OUT OF THE S PLAINS TOWARD THE E COAST WILL BRING POSSIBILITY OF A DEVELOPING STORM SLIDING NORTHEASTWARD OFF THE EASTERN SEABOARD. TRACK/STRENGTH STILL QUITE UNCERTAIN...BUT AT THIS TIME LOOKS LIKE WE/LL BE BETWEEN THAT LOW PRESSURE AREA AND A HIGH OVER OHIO VALLEY...LIKELY KEEPING CLOUDS AND SCT SHOWERS AROUND AS TEMPS COOL BACK DOWN A BIT. && .AVIATION /04Z SUNDAY THROUGH THURSDAY/... DID BACK OFF ON THE MVFR CONDITIONS FOR JST OVERNIGHT. LOOKS LIKE THE RAIN AND SLEET IS MAINLY SOUTH OF PA NOW. ATTENTION TURNS TO THE SMALL SYSTEM OVER THE OH VLY. WILL CONTINUE TO MONITOR THIS. EARLIER DISCUSSION BELOW. OTHER THAN A FEW SHOWERS WITH PERHAPS MVFR CONDITIONS AT JST LATER TONIGHT...LOOKING AT JUST HIGH AND MID LVL CLDS AT OTHER SITES WITH VFR CONDITIONS TONIGHT. AN UPPER LVL TROUGH COULD BRING SOME LOWER CLDS AND PERHAPS A SHOWER TO BFD LATE SUNDAY. FOR NOW...LEFT FCST FOR BFD VFR. MORE IN THE WAY OF WIND AND SHOWERS FOR MONDAY INTO TUE...AS WINDS SHIFT TO THE NORTH AND UPPER LVL HEIGHTS FALL. IMPROVING CONDITIONS FOR WED INTO THU...AS WEAK HIGH PRESSURE BUILDS EAST. OUTLOOK... MON-TUE...VFR...AREAS OF MVFR WITH RAIN OR SNOW SHOWERS. WED-THU...NO SIG WX. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...FITZGERALD/LA CORTE NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD/LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1045 PM EDT SAT APR 25 2015 .SYNOPSIS... WEAKENING LOW PRESSURE WILL TRACK SOUTH OF PENNSYLVANIA TONIGHT. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE STATE ON SUNDAY. A PERSISTENT UPPER LEVEL TROUGH OVER THE NORTHEASTERN UNITED STATES WILL FAVOR UNSEASONABLY COOL TEMPERATURES THROUGH THE END OF THE MONTH. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... WEAKENING SHORTWAVE SLIPPING SOUTH OF PA THIS EVENING. RADAR TRENDS AND HRRR SUGGEST DWINDLING BAND OF RAIN ASSOC WITH FGEN FORCING IN THE 8-7H LYR WILL ONLY JUST GRAZE SOUTHERN SOMERSET/BEDFORD COUNTIES THIS EVENING. SOME SNOW EVEN REPORTED AT GARRETT CO AIRPORT...BUT PRECIP RTS/EVAP COOLING PROBABLY WON/T BE SIG ENOUGH TO PRODUCE ANY SNOW IN PA. NORTHERLY FLOW WILL ADVECT DRIER AIR INTO THE REGION LATER TONIGHT...ENDING THE THREAT OF RAIN ALONG THE S TIER AND BRINGING CLEARING SKIES TO THE NORTHERN COUNTIES. BLEND OF LATEST LAMP/RAP OUTPUT SUPPORTS OVERNIGHT LOWS FROM THE U20S ACROSS THE N MTNS...TO THE U30S ACROSS THE LOW ELEVATIONS ALONG THE MD BORDER. HAVE ADDED FROST TO THE FCST ACROSS THE NORTHERN HALF OF THE STATE...WHERE SKIES ARE LIKELY TO BECOME MCLEAR OVERNIGHT. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... NARROW SFC RIDGE AND ASSOC BAND OF DRY AIR/LOW PWATS OVR UPSTATE NY THIS EVENING WILL SLIDE SOUTH INTO CENTRAL PA SUNDAY MORNING. THUS...SEE A MAINLY SUNNY START TO THE DAY. HOWEVER...UPPER TROF AND ASSOC COOL TEMPS ALOFT WILL BE SWINGING SOUTH INTO THE STATE BY AFTN. THUS...EXPECT PLENTY OF AFTN CU AND EVEN A FEW ISOLD -SHRA...ESP OVR THE N MTNS. GIVEN THE EXPECTED SPARSITY OF COVERAGE AND LOW PWATS EXPECT MEASURABLE RAINFALL TO BE A VERY LOW PROBABILITY. THUS...WILL NOT EXPLICITLY MENTION -SHRA IN FCST ATTM. 18Z GEFS MEAN 8H TEMPS SUPPORT MAX TEMPS FROM NR 50F ACROSS THE NW MTNS...TO NR 60F ACROSS THE LOWER SUSQ VALLEY...STILL WELL BLW NORMAL FOR LATE APRIL. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... ACTIVE NORTHERN AND SOUTHERN STREAM SPLIT FLOW PATTERN ACROSS NORTH AMERICA WILL KEEP THE REGION IN UPPER LEVEL TROFFINESS THROUGH MUCH OF THE PERIOD. THE BLOCKED UP NRN STREAM...GENERALLY NW FLOW PATTERN OVER THE NORTHEAST WILL TEND TO SHUNT SRN STREAM SYSTEM TO THE SOUTH OF PA. EARLY NEXT WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...THIS LOW FINALLY LIFTS OUT FOR GOOD..BUT DIGGING TROUGH FROM UPPER MIDWEST WILL EXTEND INTO THE SOUTHEAST U.S. BY LATE WEEK...COMBINED WITH A SOUTHERN STREAM SHORTWAVE LIFTING OUT OF THE S PLAINS TOWARD THE E COAST WILL BRING POSSIBILITY OF A DEVELOPING STORM SLIDING NORTHEASTWARD OFF THE EASTERN SEABOARD. TRACK/STRENGTH STILL QUITE UNCERTAIN...BUT AT THIS TIME LOOKS LIKE WE/LL BE BETWEEN THAT LOW PRESSURE AREA AND A HIGH OVER OHIO VALLEY...LIKELY KEEPING CLOUDS AND SCT SHOWERS AROUND AS TEMPS COOL BACK DOWN A BIT. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... OTHER THAN A FEW SHOWERS WITH PERHAPS MVFR CONDITIONS AT JST LATER TONIGHT...LOOKING AT JUST HIGH AND MID LVL CLDS AT OTHER SITES WITH VFR CONDITIONS TONIGHT. AN UPPER LVL TROUGH COULD BRING SOME LOWER CLDS AND PERHAPS A SHOWER TO BFD LATE SUNDAY. FOR NOW...LEFT FCST FOR BFD VFR. MORE IN THE WAY OF WIND AND SHOWERS FOR MONDAY INTO TUE...AS WINDS SHIFT TO THE NORTH AND UPPER LVL HEIGHTS FALL. IMPROVING CONDITIONS FOR WED INTO THU...AS WEAK HIGH PRESSURE BUILDS EAST. OUTLOOK... MON-TUE...VFR...AREAS OF MVFR WITH RAIN OR SNOW SHOWERS. WED-THU...NO SIG WX. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...FITZGERALD/LA CORTE NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD/LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
928 PM EDT SAT APR 25 2015 .SYNOPSIS... WEAKENING LOW PRESSURE WILL TRACK SOUTH OF PENNSYLVANIA TONIGHT. A WEAK RIDGE OF HIGH PRESSURE WILL BUILD SOUTH ACROSS THE STATE ON SUNDAY. A PERSISTENT UPPER LEVEL TROUGH OVER THE NORTHEASTERN UNITED STATES WILL FAVOR UNSEASONABLY COOL TEMPERATURES THROUGH THE END OF THE MONTH. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... WEAKENING SHORTWAVE SLIPPING SOUTH OF PA THIS EVENING. RADAR TRENDS AND HRRR SUGGEST DWINDLING BAND OF RAIN ASSOC WITH FGEN FORCING IN THE 8-7H LYR WILL ONLY JUST GRAZE SOUTHERN SOMERSET/BEDFORD COUNTIES THIS EVENING. SOME SNOW EVEN REPORTED AT GARRETT CO AIRPORT...BUT PRECIP RTS/EVAP COOLING PROBABLY WON/T BE SIG ENOUGH TO PRODUCE ANY SNOW IN PA. NORTHERLY FLOW WILL ADVECT DRIER AIR INTO THE REGION LATER TONIGHT...ENDING THE THREAT OF RAIN ALONG THE S TIER AND BRINGING CLEARING SKIES TO THE NORTHERN COUNTIES. BLEND OF LATEST LAMP/RAP OUTPUT SUPPORTS OVERNIGHT LOWS FROM THE U20S ACROSS THE N MTNS...TO THE U30S ACROSS THE LOW ELEVATIONS ALONG THE MD BORDER. HAVE ADDED FROST TO THE FCST ACROSS THE NORTHERN HALF OF THE STATE...WHERE SKIES ARE LIKELY TO BECOME MCLEAR OVERNIGHT. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... NARROW SFC RIDGE AND ASSOC BAND OF DRY AIR/LOW PWATS OVR UPSTATE NY THIS EVENING WILL SLIDE SOUTH INTO CENTRAL PA SUNDAY MORNING. THUS...SEE A MAINLY SUNNY START TO THE DAY. HOWEVER...UPPER TROF AND ASSOC COOL TEMPS ALOFT WILL BE SWINGING SOUTH INTO THE STATE BY AFTN. THUS...EXPECT PLENTY OF AFTN CU AND EVEN A FEW ISOLD -SHRA...ESP OVR THE N MTNS. GIVEN THE EXPECTED SPARSITY OF COVERAGE AND LOW PWATS EXPECT MEASURABLE RAINFALL TO BE A VERY LOW PROBABILITY. THUS...WILL NOT EXPLICITLY MENTION -SHRA IN FCST ATTM. 18Z GEFS MEAN 8H TEMPS SUPPORT MAX TEMPS FROM NR 50F ACROSS THE NW MTNS...TO NR 60F ACROSS THE LOWER SUSQ VALLEY...STILL WELL BLW NORMAL FOR LATE APRIL. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... ACTIVE NORTHERN AND SOUTHERN STREAM SPLIT FLOW PATTERN ACROSS NORTH AMERICA WILL KEEP THE REGION IN UPPER LEVEL TROFFINESS THROUGH MUCH OF THE PERIOD. THE BLOCKED UP NRN STREAM...GENERALLY NW FLOW PATTERN OVER THE NORTHEAST WILL TEND TO SHUNT SRN STREAM SYSTEM TO THE SOUTH OF PA. EARLY NEXT WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...THIS LOW FINALLY LIFTS OUT FOR GOOD..BUT DIGGING TROUGH FROM UPPER MIDWEST WILL EXTEND INTO THE SOUTHEAST U.S. BY LATE WEEK...COMBINED WITH A SOUTHERN STREAM SHORTWAVE LIFTING OUT OF THE S PLAINS TOWARD THE E COAST WILL BRING POSSIBILITY OF A DEVELOPING STORM SLIDING NORTHEASTWARD OFF THE EASTERN SEABOARD. TRACK/STRENGTH STILL QUITE UNCERTAIN...BUT AT THIS TIME LOOKS LIKE WE/LL BE BETWEEN THAT LOW PRESSURE AREA AND A HIGH OVER OHIO VALLEY...LIKELY KEEPING CLOUDS AND SCT SHOWERS AROUND AS TEMPS COOL BACK DOWN A BIT. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... OTHER THAN A FEW SHOWERS WITH PERHAPS MVFR CONDITIONS AT JST LATER TONIGHT...LOOKING AT JUST HIGH AND MID LVL CLDS AT OTHER SITES WITH VFR CONDITIONS TONIGHT. AN UPPER LVL TROUGH COULD BRING SOME LOWER CLDS AND PERHAPS A SHOWER TO BFD LATE SUNDAY. FOR NOW...LEFT FCST FOR BFD VFR. MORE IN THE WAY OF WIND AND SHOWERS FOR MONDAY INTO TUE...AS WINDS SHIFT TO THE NORTH AND UPPER LVL HEIGHTS FALL. IMPROVING CONDITIONS FOR WED INTO THU...AS WEAK HIGH PRESSURE BUILDS EAST. OUTLOOK... MON-TUE...VFR...AREAS OF MVFR WITH RAIN OR SNOW SHOWERS. WED-THU...NO SIG WX. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...FITZGERALD/LA CORTE NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD/LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
826 PM EDT SAT APR 25 2015 .SYNOPSIS... HIGH PRESSURE TO OUR NORTH WILL KEEP MAINLY DRY CONDITIONS IN PLACE TODAY. LOW PRESSURE MOVING FROM THE MID MISSISSIPPI TO THE CAROLINA COAST WILL BRING THE RISK OF LIGHT RAIN ACROSS SOUTHERN PENNSYLVANIA OVERNIGHT. PERSISTENT UPPER LEVEL TROUGH OVER THE NORTHEASTERN UNITED STATES WILL FAVOR UNSEASONABLY COOL TEMPERATURES THROUGH THE END OF THE MONTH. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... WEAKENING SHORTWAVE SLIPPING SOUTH OF PA THIS EVENING. RADAR TRENDS AND HRRR SUGGEST DWINDLING BAND OF RAIN ASSOC WITH FGEN FORCING IN THE 8-7H LYR WILL ONLY JUST GRAZE SOUTHERN SOMERSET/BEDFORD COUNTIES THIS EVENING. NORTHERLY FLOW WILL THEN ADVECT DRIER AIR INTO THE REGION LATER TONIGHT...ENDING THE THREAT OF RAIN ALONG THE S TIER AND BRINGING CLEARING SKIES TO THE NORTHERN COUNTIES. LOWS FROM THE MID 20S NORTH TO MID 30S SOUTH WILL BE SOME 5-10 DEG BELOW NORMAL. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... WHILE THE MAIN WAVE OF LOW PRESSURE CURRENTLY OVER THE MIDWEST GETS PINCHED OFF TO OUR SOUTH...UPPER TROUGHING AROUND THE STRONG LOW OVER THE NEW ENGLAND COASTAL WATERS WILL FEED ANY NUMBER OF WEAK SHORTWAVES DOWN AROUND THE ITS BACK SIDE INTO THE REGION FROM THE NORTH. DEEP LAYER MOISTURE WILL BE SPARSE...BUT THE COLD AIR ALOFT AND STRONG APRIL SUN COULD CONSPIRE TO POP OFF SOME LOW TOPPED SHOWERS. THE OPERATIONAL GFS AND ECMWF SHOW SOME LIGHT QPF FOR THE AFTERNOON OVER THE NORTHERN TIER...WHILE THE GEFS AND SREF IMPLY SHOWERS WILL BE A VERY LOW PROBABILITY OCCURRENCE. AT THIS POINT I WILL DOWNPLAY THE CHANCES. IT LOOKS TO REMAIN ON THE UNSEASONABLY CHILLY SIDE DESPITE WHAT SHOULD WORK OUT TO BE A MIX OF SUN AND CLOUDS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... ACTIVE NORTHERN AND SOUTHERN STREAM SPLIT FLOW PATTERN ACROSS NORTH AMERICA WILL KEEP THE REGION IN UPPER LEVEL TROFFINESS THROUGH MUCH OF THE PERIOD. THE BLOCKED UP NRN STREAM...GENERALLY NW FLOW PATTERN OVER THE NORTHEAST WILL TEND TO SHUNT SRN STREAM SYSTEM TO THE SOUTH OF PA. EARLY NEXT WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...THIS LOW FINALLY LIFTS OUT FOR GOOD..BUT DIGGING TROUGH FROM UPPER MIDWEST WILL EXTEND INTO THE SOUTHEAST U.S. BY LATE WEEK...COMBINED WITH A SOUTHERN STREAM SHORTWAVE LIFTING OUT OF THE S PLAINS TOWARD THE E COAST WILL BRING POSSIBILITY OF A DEVELOPING STORM SLIDING NORTHEASTWARD OFF THE EASTERN SEABOARD. TRACK/STRENGTH STILL QUITE UNCERTAIN...BUT AT THIS TIME LOOKS LIKE WE/LL BE BETWEEN THAT LOW PRESSURE AREA AND A HIGH OVER OHIO VALLEY...LIKELY KEEPING CLOUDS AND SCT SHOWERS AROUND AS TEMPS COOL BACK DOWN A BIT. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... OTHER THAN A FEW SHOWERS WITH PERHAPS MVFR CONDITIONS AT JST LATER TONIGHT...LOOKING AT JUST HIGH AND MID LVL CLDS AT OTHER SITES WITH VFR CONDITIONS TONIGHT. AN UPPER LVL TROUGH COULD BRING SOME LOWER CLDS AND PERHAPS A SHOWER TO BFD LATE SUNDAY. FOR NOW...LEFT FCST FOR BFD VFR. MORE IN THE WAY OF WIND AND SHOWERS FOR MONDAY INTO TUE...AS WINDS SHIFT TO THE NORTH AND UPPER LVL HEIGHTS FALL. IMPROVING CONDITIONS FOR WED INTO THU...AS WEAK HIGH PRESSURE BUILDS EAST. OUTLOOK... MON-TUE...VFR...AREAS OF MVFR WITH RAIN OR SNOW SHOWERS. WED-THU...NO SIG WX. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...FITZGERALD/LA CORTE SHORT TERM...ROSS/LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1050 PM EDT SAT APR 25 2015 .SYNOPSIS... AN AREA OF LOW PRESSURE WILL MOVE EAST FROM KENTUCKY AND TENNESSEE TO NORTH CAROLINA TONIGHT...THEN OFF THE COAST ON SUNDAY. COOL AND DRY HIGH PRESSURE DROPS DOWN FROM CENTRAL CANADA SUNDAY AND WILL BE OUR WEATHER MAKER FOR THE FIRST HALF OF THE WEEK. EXPECT LOW PRESSURE TO MOVE EAST FROM TEXAS IN MID WEEK AND BRING MORE RAIN WEDNESDAY AND THURSDAY. && .NEAR TERM /THROUGH SUNDAY/... AS OF 1045 PM EDT SATURDAY...UPSTREAM CONVECTION ACROSS SE/SC KENTUCKY CONTINUES TO SLIDE SOUTHEAST ALONG AN INSTABILITY AXIS THROUGH MIDDLE TN. LATEST HRRR CONTINUES TO INDICATE SURVIVAL OF SAID CONVECTIVE LINE AS IT APPROACHES THE NC HIGH TERRAIN ALONG THE TN STATE LINE. A SHARP INSTABILITY GRADIENT ACROSS EXTREME EASTERN TN WILL CONTINUE TO FUEL THUNDERSTORMS THROUGH AT LEAST MIDNIGHT...BEFORE IMPACTING THE MTNS AROUND 2AM WHEN QUICK WEAKENING OF ACTIVITY IS EXPECTED. THUS...THINK CURRENT POP TRENDS REMAIN VALID AND OPTED NOT TO MAKE ANY ADJUSTMENTS. WILL ALSO CONTINUE TO NOTE THAT AN ABUNDANCE OF GUIDANCE FAVORS AT LEAST PATCHY DENSE FOG ACROSS THE NC/SC PIEDMONT ALONG THE I77 CORRIDOR OVERNIGHT. THUS A DFA MAY BE NEEDED LATER. PREVIOUS DISCUSSION... AT 230 PM EDT SATURDAY...A LOW AMPLITUDE UPPER TROUGH WAS LOCATED OVER THE SOUTHERN APPALACHIANS THIS AFTERNOON...WHILE A CLOSED LOW WAS OVER THE MID MS RIVER VALLEY. THE TROUGH IS EXPECTED TO DEAMPLIFY THIS EVENING WHILE THE CLOSED UP FILLS...RESULTING IN ZONAL FOR OVER THE SE. SHORTWAVES MOVING THROUGH THIS FLOW WILL CROSS OUR AREA THIS EVENING...AND AGAIN ON SUNDAY MORNING. AT THE SURFACE...A STATIONARY FRONT WAS LOCATED FROM THE NORTHERN NC MOUNTAINS TO THE NC OUTER BANKS EARLY THIS AFTERNOON. ALTHOUGH MOIST ISENTROPIC UPGLIDE AND LOW CLOUDS REMAIN OVER MOST OF OUR AREA...THE BULK OF PRECIPITATION HAS MOVES EAST OF THE AREA WITH A DEPARTING SHORTWAVE. PRECIPITATION CHANCES ARE EXPECTED TO INCREASE AGAIN THIS EVENING THE FRONT TO OUR NORTH DROPS SOUTH...EVEN AS UPGLIDE WEAKENS. INSTABILITY AND SHEAR BOTH INCREASE ABOVE A LOW LEVEL INCREASE OVERNIGHT...BEFORE A DECREASE TOWARD DAWN...INCREASING SUPPORT FOR ELEVATED ORGANIZED CONVECTION. MINIMUM TEMPERATURES WILL RUN ABOVE NORMAL UNDER CLOUD COVER. AS THE COLD FRONT MOVES SOUTH ACROSS OUR AREA ON SUNDAY...A DRYING DOWNSLOPE FLOW WILL FOLLOW IN ITS WAKE...RESULTING IN WARMING TEMPERATURES. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... AS OF 210 PM SATURDAY...AS COLD FRONT SAGS SOUTH ACROSS THE AREA... ISLD/SCT SHOWERS WILL REMAIN POSSIBLE ACROSS SOUTHERN PIEDMONT AREAS INTO SUNDAY EVENING. MEANWHILE...A RELATIVELY MODEST/MOIST NW FLOW COULD YIELD SOME SCATTERED SHOWERS NEAR THE TENNESSEE BORDER AS WELL. POPS WILL GENERALLY BE CONFINED TO THOSE AREAS DURING THE EVENING HOURS. THE REMAINDER OF THE SHORT TERM WILL BE PLEASANTLY COOL AND DRY UNDER THE INFLUENCE OF A BROAD LONG WAVE TROUGH ALONG THE EAST COAST/WESTERN ATLANTIC...WITH A COUPLE OF PERIODIC SHORT WAVE TROUGHS ONLY ACTING TO REINFORCE THE BELOW CLIMO TEMPS. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 215 PM SATURDAY...CHANCES FOR PRECIPITATION WILL GRADUALLY INCREASE THROUGH MID-WEEK...AS A SOUTHERN STREAM AREA OF LOW PRESSURE WOBBLES OUT OF THE FOUR CORNERS REGION/TEXAS AND OPENS UP ACROSS THE SOUTHEAST. THIS WILL CREATE COMPLICATIONS TO THE UPPER PATTERN IN TERMS OF HOW THE NORTHERN AND SOUTHERN STREAMS WILL INTERACT (IF AT ALL)...AND INDEED GLOBAL MODEL SOLUTIONS ARE QUITE DISPARATE REGARDING THE SYNOPTIC DETAILS FOR MID-WEEK...ESP REGARDING SOUTHEAST COASTAL LOW PRESSURE. NEVERTHELESS...ALL GLOBAL MODELS AND ENSEMBLE SOLUTIONS DEPICT AT LEAST A WEAK WAVE OF LOW PRESSURE ACROSS THE NORTHERN GULF BY TUE AFTERNOON...THUS CHANCE POPS WILL SPREAD INTO THE AREA FROM THE SOUTHWEST TUE NIGHT INTO WEDNESDAY. UNCERTAINTY REALLY EXPLODES AFTER WED...WHEN DETERMINISTIC MODEL SOLUTIONS DIVERGE CONSIDERABLY (WITH THE ECMWF DEVELOPING AN INTENSE/MILLER-A CYCLONE OFF THE CAROLINA COAST BY THURSDAY...WHILE THE GFS BARELY DEPICTS A WEAK WAVE IN THIS AREA). NEVERTHELESS...ENSEMBLE GLOBAL ENSEMBLE MEAN SOLUTIONS SUPPORT MAINTAINING LOW POPS INTO THURSDAY. DRY AND SEASONABLY WARM CONDITIONS ARE EXPECTED TO RETURN FOR LATE WEEK. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... AT KCLT...INITIALIZED TAF MVFR AS CURRENT IFR RESTRICTIONS SHOULD IMPROVE SHORTLY. ADDED TSRA TEMPO FROM 07Z-10Z TO ACCOUNT FOR UPSTREAM MCS PROPAGATION/SURVIVAL THROUGH THE MOUNTAINS AS SHOWN ON THE LATEST HRRR. HOWEVER...IF THIS TRACK DOES PAN OUT...LITTLE TO NO INSTABILITY WILL BE AVAILABLE FOR CONVECTION THUS ANY STRONG TSRA IS LIKELY RULED OUT. ACTUALLY WOULDNT BE SURPRISED IF ITS NOTHING MORE THAN A FEW SHOWERS. OTHERWISE...GUIDANCE CONTINUES TO FAVOR PATCHY DENSE FOG AROUND THE LOWER NC PIEDMONT BY MORNING THUS ADDED FM GROUP TO INDICATE IFR RESTRICTIONS. IMPROVED TAF TO LOW VFR AROUND 15Z WITH NORTHERLY WINDS PREVAILING AHEAD OF A PROB30 IN THE AFTN FOR POSSIBLE CONVECTION ALONG SLOW MOVING FRONTAL AXIS. ELSEWHERE...MODELS STILL FAVOR PROLONGED LIFR/IFR RESTRICTIONS AT KHKY THUS TAF REFLECTS SUCH. OTHERWISE...ALL TAFS INITIALIZE VFR THROUGH THE EARLY EVENING HOURS. MCS SLIDING THROUGH CENTRAL KY AT THIS TIME IS PROGGED TO ADVANCE THROUGH THE PLATEAU INTO THE HIGH TERRAIN OF WESTERN NC AFTER MIDNIGHT. SOME CAM SOLUTIONS INDICATE SURVIVAL OF SAID MCS THROUGH THE MOUNTAINS. THUS...TAFS FEATURE VCTS MENTION TO ACCOUNT FOR ANY ENHANCED CONVECTION. AS WITH KCLT ABOVE...EXPECTING INSTABILITY TO BE AT A PREMIUM...ESPECIALLY EAST OF THE MTNS THEREFORE NO ROBUST CONVECTION IS EXPECTED. WITH THAT LOWERED ALL SITES TO EITHER LOW VFR OR MVFR AMIDST LIGHT/MODERATE NORTHERLY WINDS. DID INCLUDE EARLY MORNING PATCHY FOG AT ALL SITES WITH SOME ISOLATED DENSE FOG EXPECTED OVER THE NC PIEDMONT...THUS DO CARRY 1/2SM AT KHKY. OTHERWISE CONDITIONS WILL IMPROVE THROUGH MORNING WITH SHRA/TSRA EXITING THE REGION...IF PRESENT. DID REINTRODUCE WX MENTION LATE IN THE PERIOD TO ACCOUNT FOR SLOW MOVING FRONTAL AXIS ON SUNDAY AFTERNOON/EVENING. OUTLOOK...A COLD FRONT WILL SWEEP ACROSS THE REGION ON SUNDAY THEN FOLLOWED BY DRY HIGH PRESSURE THROUGH TUESDAY. ANOTHER LOW PRESSURE SYSTEM MAY TRACK ACROSS THE DEEP SOUTH WEDNESDAY AND THURSDAY. CONFIDENCE TABLE... 02-08Z 08-14Z 14-20Z 20-00Z KCLT HIGH 95% MED 69% HIGH 86% MED 70% KGSP MED 75% HIGH 89% HIGH 98% HIGH 80% KAVL HIGH 100% HIGH 100% HIGH 94% HIGH 90% KHKY MED 75% MED 74% LOW 56% MED 77% KGMU MED 76% HIGH 94% HIGH 98% HIGH 95% KAND MED 79% HIGH 94% HIGH 94% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...DEO NEAR TERM...CDG/JAT SHORT TERM...JDL LONG TERM...JDL AVIATION...CDG
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1252 PM CDT FRI APR 24 2015 .UPDATE... ISSUED AT 1252 PM CDT FRI APR 24 2015 IMPACT OF WAVE LIFTING ACROSS NORTHWEST IOWA AT MIDDAY HAS BEEN TWOFOLD...FIRST TO GENERATE AS EXPECTED SCATTERED SHOWERS AND A FEW THUNDERSTORMS MAINLY NORTHWEST IOWA INTO SOUTHWEST MINNESOTA...AND SECOND TO BRING A GREATER DEAL OF CLEARING TO THE WESTERN/SOUTHERN CWA. SOME ALTERATIONS MADE TO THE CONVECTIVE TRENDS THROUGH THE DAY. WITH SUBSIDENCE FOR THE TIME BEING SETTLING ACROSS THE CWA... HAVE DROPPED MOST OF THE LOWER POPS IN REGION BEHIND WAVE...WHILE INCREASING CERTAINTY A BIT AHEAD. CONCERN THEN BECOMES WITH THE LATTER AFTERNOON...WHERE THE DESTABILIZATION FROM THE ADDED HEATING WILL ERODE WEAK CAPPING. AT LEAST MODEST CONVERGENCE ALONG BOUNDARY LIKELY TO POOL ENOUGH MOISTURE TO RESULT IN A 500-1200 J/KG MIXED LAYER INSTABILITY...BUT DEEPER LAYER SHEAR IS FAIRLY WEAK DUE TO THE LACK OF ANY MID LEVEL WINDS. PERHAPS COULD SCARE UP A PULSE MULTICELL MARGINAL SEVERE HAILER ACROSS AREAS NEAR/WEST OF THE JAMES RIVER LATE AFTERNOON INTO EARLY EVENING...BUT OVERALL ANY SEVERE THREAT IS MINIMAL. TOUGH PART OF TEMPERATURE FORECAST FOR LOWER MISSOURI VALLEY IS HOW WARM IT COULD GET PRIOR TO RETURN OF STRATUS FROM THE SOUTH AROUND MID AFTERNOON. PUSHED READINGS UP QUITE A BIT...FROM 4 TO 7 DEGREES...BUT MAY NOT BE ENOUGH IF CAN REACH POTENTIAL INDICATED IN RAP MODEL...WHICH IS MUCH MORE IN TUNE WITH CURRENT TRENDS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 415 AM CDT FRI APR 24 2015 NOT EXACTLY A CLEAR CUT FORECAST WITH REGARD TO PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. SEEING JUST SPOTTY ELEVATED SHOWERS IN OUR FAR SOUTHEAST THUS FAR THIS MORNING...WITH LOW LEVEL JET FOCUSING MORE CONSOLIDATED PRECIPITATION WELL NORTH OF OUR AREA. MORE CONCENTRATED LOW LEVEL MOISTURE INCREASE EXPECTED OVER THE WESTERN CWA THROUGH THE EARLY MORNING...THOUGH THUS FAR THIS HAS BEEN SLOWER TO DEVELOP THAN EXPECTED. NEVERTHELESS...BEGINNING TO SEE SPOTTY ELEVATED ECHOES DEVELOP THROUGH EASTERN NEBRASKA AND HIGH RES MODELS IN FAIR AGREEMENT DEVELOPING ISOLATED SHOWERS FROM NEAR THE JAMES VALLEY TO WEST OF I-29 THIS MORNING. OVERALL THOUGH... BETTER POTENTIAL FOR SHOWERS THROUGH THE DAY APPEARS TO BE IN OUR FAR SOUTHEAST WHERE DEEP ISENTROPIC LIFT PERSISTS THROUGH MUCH OF THE DAY. DEPTH OF MOISTURE A BIT OF A CONCERN AND HAVE TRIMMED BACK RAINFALL AMOUNTS A BIT FROM PREVIOUS FORECAST FOR TODAY...WITH AROUND A TENTH OF AN INCH OR A LITTLE MORE ALONG/SOUTHEAST OF HIGHWAY 60 CORRIDOR...AND LESS THAN A TENTH ELSEWHERE IN THE CWA. AS FOR TEMPERATURES...HOLDING A FEW DEGREES COOLER THAN THURSDAY IN THE EAST DUE TO THICKER CLOUD COVER AND PRECIP CHANCES...BUT A SHADE WARMER WEST WHERE 925MB TEMPERATURES ARE FORECAST TO CLIMB A DEGREE OR TWO HIGHER THAN THURSDAY IN THERMAL RIDGE JUST AHEAD OF THE SURFACE BOUNDARY. WITH THE WARMER TEMPERATURES AND BETTER LOW LEVEL MOISTURE WEST...BEGIN TO SEE BETTER SURFACE BASED INSTABILITY AND LEADING TO POSSIBLE ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT IN OUR FAR WEST BY LATE AFTERNOON. GFS/NAM SHOWING SBCAPE VALUES REACHING 1000-1500 J/KG...BUT RAP CONSIDERABLY LOWER DUE TO WARMER MID-UPPER LEVEL TEMPERATURES. IF GFS/NAM PROFILES PAN OUT...CANNOT ARGUE WITH SPC MARGINAL THREAT FOR HAIL IN OUR SOUTHWEST CWA LATE THIS AFTERNOON/EVENING. FOR TONIGHT...UPPER TROUGH SWINGING OUT OF THE CENTRAL ROCKIES SHOULD BRING INCREASING THREAT OF RAIN TO OUR SOUTHEAST AS IT STRENGTHENS AND SLIDES EAST THROUGH THE CENTRAL PLAINS. QUESTION IS HOW FAR NORTH THE PRECIP SHIELD WILL EXPAND BEFORE THE WAVE PULLS EAST LATE TONIGHT. FOR NOW HAVE EXPANDED LIKELY POPS A BIT FARTHER NORTH...TO NEAR A VERMILLION-WORTHINGTON LINE...WITH MORE WIDESPREAD ACTIVITY SOUTH OF SIOUX CITY-SPENCER. PRECIP AMOUNTS AGAIN EXPECTED TO REMAIN ON THE LIGHTER SIDE...AROUND A TENTH OR TWO OVER NORTHWEST IOWA AND MUCH LESS FOR MOST OF SOUTHEAST SOUTH DAKOTA AND SOUTHWEST MINNESOTA. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 415 AM CDT FRI APR 24 2015 ON SATURDAY MORNING...IT IS UNCLEAR HOW FAR TO EXTEND POPS FROM NORTHWEST IOWA BACK TO THE WEST. MOST MODELS SUGGEST POPS ACROSS NORTHWEST IOWA...BUT SOLUTIONS VARY TO THE WEST AS LIMITED DYNAMICS AND RELATIVELY SHALLOW MOISTURE LIMIT PRECIPITATION POTENTIAL. WITH EASTERLY FLOW CONTINUING THROUGH THE DAY...KEPT TEMPERATURES BELOW NORMAL IN THE EAST WITH WARMER HIGHS ACROSS SOUTH CENTRAL SOUTH DAKOTA. MODELS SHOW SWATH OF DRIER AIR WORKING INTO THE REGION ON SUNDAY FROM THE EAST. WITH RELATIVELY DRY AIR...WENT AHEAD AND LOWERED DEW POINTS AND SKY COVER AND RAISED TEMPERATURES. THIS ONCE AGAIN WILL CREATE ELEVATED FIRE WEATHER CONCERNS THOUGH WITH WINDS ALOFT ONLY IN THE 15-20 KNOTS RANGE...AM NOT EXPECTING WINDS TO GET STRONG ENOUGH FOR RED FLAG. MONDAY LOOKS TO BE A RELATIVELY PLEASANT DAY ACROSS THE AREA WITH WEAK WINDS AHEAD OF A FRONT MOVING THROUGH MONDAY EVENING. LEFT SOME SLIGHT CHANCE POPS ACROSS THE NORTH WITH THE FRONTAL PASSAGE. CONSIDERED REMOVING POPS ALL TOGETHER AS MOISTURE REMAINS QUITE LIMITED. LOOKS TO BE YET ANOTHER DRY WEEK ACROSS THE REGION. UPPER LEVEL JET BUCKLES TO THE NORTH LEADING TO A WARMING TREND. WINDS APPEAR TO INCREASE LATE IN THE WEEK...POTENTIALLY CREATING ADDITIONAL FIRE WEATHER CONCERNS LATE NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1252 PM CDT FRI APR 24 2015 HAVE BROKEN OUT INTO LARGELY VFR CONDITIONS ACROSS THE AREA WITH EXCEPTION OF AREAS OF MVFR CEILINGS AHEAD OF UPPER WAVE LIFTING ACROSS NORTHWEST IOWA. MVFR STRATUS WILL ATTEMPT TO SPREAD BACK NORTHWARD THROUGH EASTERN NEBRASKA TOWARD KSUX BY MID TO LATE AFTERNOON...FIGHTING MIXING ALL THE WAY. OTHER CONCERN WILL BE WITH POTENTIAL CONVECTIVE DEVELOPMENT VERY LATE AFTERNOON AND EARLY EVENING NEAR SURFACE CONVERGENCE TOWARD SOUTH CENTRAL SD AND THE LOWER TO MID JAMES VALLEY. CONVECTION WOULD LIKELY HAVE BRIEF IFR VISIBILITY AND MVFR CEILINGS. WHILE ACKNOWLEDGE THERE IS A SMALL THREAT AT KFSD AND KSUX...WOULD SEEM A BIT LOW PROBABILITY AND MORE DIFFICULT TO TIME AND THUS HAVE LEFT OUT ON THIS 18Z ISSUANCE. MORE WIDESPREAD MVFR TO IFR CEILINGS WILL DEVELOP DURING THE EVENING AND OVERNIGHT...LINGERING THROUGH SATURDAY MORNING AS MOIST EASTERLY FLOW INTENSIFIES. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ UPDATE...CHAPMAN SHORT TERM...JH LONG TERM... AVIATION...CHAPMAN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
648 AM CDT FRI APR 24 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 415 AM CDT FRI APR 24 2015 NOT EXACTLY A CLEAR CUT FORECAST WITH REGARD TO PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. SEEING JUST SPOTTY ELEVATED SHOWERS IN OUR FAR SOUTHEAST THUS FAR THIS MORNING...WITH LOW LEVEL JET FOCUSING MORE CONSOLIDATED PRECIPITATION WELL NORTH OF OUR AREA. MORE CONCENTRATED LOW LEVEL MOISTURE INCREASE EXPECTED OVER THE WESTERN CWA THROUGH THE EARLY MORNING...THOUGH THUS FAR THIS HAS BEEN SLOWER TO DEVELOP THAN EXPECTED. NEVERTHELESS...BEGINNING TO SEE SPOTTY ELEVATED ECHOES DEVELOP THROUGH EASTERN NEBRASKA AND HIGH RES MODELS IN FAIR AGREEMENT DEVELOPING ISOLATED SHOWERS FROM NEAR THE JAMES VALLEY TO WEST OF I-29 THIS MORNING. OVERALL THOUGH... BETTER POTENTIAL FOR SHOWERS THROUGH THE DAY APPEARS TO BE IN OUR FAR SOUTHEAST WHERE DEEP ISENTROPIC LIFT PERSISTS THROUGH MUCH OF THE DAY. DEPTH OF MOISTURE A BIT OF A CONCERN AND HAVE TRIMMED BACK RAINFALL AMOUNTS A BIT FROM PREVIOUS FORECAST FOR TODAY...WITH AROUND A TENTH OF AN INCH OR A LITTLE MORE ALONG/SOUTHEAST OF HIGHWAY 60 CORRIDOR...AND LESS THAN A TENTH ELSEWHERE IN THE CWA. AS FOR TEMPERATURES...HOLDING A FEW DEGREES COOLER THAN THURSDAY IN THE EAST DUE TO THICKER CLOUD COVER AND PRECIP CHANCES...BUT A SHADE WARMER WEST WHERE 925MB TEMPERATURES ARE FORECAST TO CLIMB A DEGREE OR TWO HIGHER THAN THURSDAY IN THERMAL RIDGE JUST AHEAD OF THE SURFACE BOUNDARY. WITH THE WARMER TEMPERATURES AND BETTER LOW LEVEL MOISTURE WEST...BEGIN TO SEE BETTER SURFACE BASED INSTABILITY AND LEADING TO POSSIBLE ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT IN OUR FAR WEST BY LATE AFTERNOON. GFS/NAM SHOWING SBCAPE VALUES REACHING 1000-1500 J/KG...BUT RAP CONSIDERABLY LOWER DUE TO WARMER MID-UPPER LEVEL TEMPERATURES. IF GFS/NAM PROFILES PAN OUT...CANNOT ARGUE WITH SPC MARGINAL THREAT FOR HAIL IN OUR SOUTHWEST CWA LATE THIS AFTERNOON/EVENING. FOR TONIGHT...UPPER TROUGH SWINGING OUT OF THE CENTRAL ROCKIES SHOULD BRING INCREASING THREAT OF RAIN TO OUR SOUTHEAST AS IT STRENGTHENS AND SLIDES EAST THROUGH THE CENTRAL PLAINS. QUESTION IS HOW FAR NORTH THE PRECIP SHIELD WILL EXPAND BEFORE THE WAVE PULLS EAST LATE TONIGHT. FOR NOW HAVE EXPANDED LIKELY POPS A BIT FARTHER NORTH...TO NEAR A VERMILLION-WORTHINGTON LINE...WITH MORE WIDESPREAD ACTIVITY SOUTH OF SIOUX CITY-SPENCER. PRECIP AMOUNTS AGAIN EXPECTED TO REMAIN ON THE LIGHTER SIDE...AROUND A TENTH OR TWO OVER NORTHWEST IOWA AND MUCH LESS FOR MOST OF SOUTHEAST SOUTH DAKOTA AND SOUTHWEST MINNESOTA. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 415 AM CDT FRI APR 24 2015 ON SATURDAY MORNING...IT IS UNCLEAR HOW FAR TO EXTEND POPS FROM NORTHWEST IOWA BACK TO THE WEST. MOST MODELS SUGGEST POPS ACROSS NORTHWEST IOWA...BUT SOLUTIONS VARY TO THE WEST AS LIMITED DYNAMICS AND RELATIVELY SHALLOW MOISTURE LIMIT PRECIPITATION POTENTIAL. WITH EASTERLY FLOW CONTINUING THROUGH THE DAY...KEPT TEMPERATURES BELOW NORMAL IN THE EAST WITH WARMER HIGHS ACROSS SOUTH CENTRAL SOUTH DAKOTA. MODELS SHOW SWATH OF DRIER AIR WORKING INTO THE REGION ON SUNDAY FROM THE EAST. WITH RELATIVELY DRY AIR...WENT AHEAD AND LOWERED DEW POINTS AND SKY COVER AND RAISED TEMPERATURES. THIS ONCE AGAIN WILL CREATE ELEVATED FIRE WEATHER CONCERNS THOUGH WITH WINDS ALOFT ONLY IN THE 15-20 KNOTS RANGE...AM NOT EXPECTING WINDS TO GET STRONG ENOUGH FOR RED FLAG. MONDAY LOOKS TO BE A RELATIVELY PLEASANT DAY ACROSS THE AREA WITH WEAK WINDS AHEAD OF A FRONT MOVING THROUGH MONDAY EVENING. LEFT SOME SLIGHT CHANCE POPS ACROSS THE NORTH WITH THE FRONTAL PASSAGE. CONSIDERED REMOVING POPS ALL TOGETHER AS MOISTURE REMAINS QUITE LIMITED. LOOKS TO BE YET ANOTHER DRY WEEK ACROSS THE REGION. UPPER LEVEL JET BUCKLES TO THE NORTH LEADING TO A WARMING TREND. WINDS APPEAR TO INCREASE LATE IN THE WEEK...POTENTIALLY CREATING ADDITIONAL FIRE WEATHER CONCERNS LATE NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 648 AM CDT FRI APR 24 2015 AREAS OF MVFR CEILINGS NEAR/EAST OF I-29 CORRIDOR AT THE START OF THE PERIOD EXPECTED TO BECOME MORE WIDESPREAD THROUGH THE DAY AS INCREASING LOW LEVEL MOISTURE SPREADS INTO THE REGION. SHOWERS AND ISOLATED THUNDERSTORMS WILL ALSO ACCOMPANY THE INCREASING MOISTURE ACROSS THE AREA TODAY THROUGH TONIGHT. BOTH THE LOW CEILINGS AND GREATER CHANCE OF PRECIPITATION WILL BE MORE PROMINENT EAST OF THE JAMES RIVER VALLEY...WITH THE KHON TAF SITE LARGELY EXPECTED TO REMAIN VFR UNTIL AFTER 03Z THIS EVENING WHEN A MORE EASTERLY LOW LEVEL FLOW WILL PULL THE MVFR CEILINGS WESTWARD INTO THE JAMES VALLEY. GIVEN UNCERTAINTY REGARDING TIMING/LOCATION OF THUNDER CHANCES... OPTED TO LEAVE OUT OF THE TAFS AT THIS TIME. HOWEVER...POTENTIAL CANNOT BE RULED OUT GIVEN MID LEVEL INSTABILITY. KHON MAY ACTUALLY SEE A GREATER THUNDER THREAT THAN KFSD/KSUX...AS INSTABILITY MAY BECOME SURFACE BASED THERE IN THE LATE AFTERNOON/EVENING. HOWEVER THIS THREAT CONDITIONAL ON WHETHER PRECIPITATION ACTUALLY DEVELOPS IN THAT FAR NORTH...SO AGAIN WILL KEEP THE TAF DRY FOR NOW. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM...JH LONG TERM... AVIATION...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
416 AM CDT FRI APR 24 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 415 AM CDT FRI APR 24 2015 NOT EXACTLY A CLEAR CUT FORECAST WITH REGARD TO PRECIPITATION CHANCES OVER THE NEXT 24 HOURS. SEEING JUST SPOTTY ELEVATED SHOWERS IN OUR FAR SOUTHEAST THUS FAR THIS MORNING...WITH LOW LEVEL JET FOCUSING MORE CONSOLIDATED PRECIPITATION WELL NORTH OF OUR AREA. MORE CONCENTRATED LOW LEVEL MOISTURE INCREASE EXPECTED OVER THE WESTERN CWA THROUGH THE EARLY MORNING...THOUGH THUS FAR THIS HAS BEEN SLOWER TO DEVELOP THAN EXPECTED. NEVERTHELESS...BEGINNING TO SEE SPOTTY ELEVATED ECHOES DEVELOP THROUGH EASTERN NEBRASKA AND HIGH RES MODELS IN FAIR AGREEMENT DEVELOPING ISOLATED SHOWERS FROM NEAR THE JAMES VALLEY TO WEST OF I-29 THIS MORNING. OVERALL THOUGH... BETTER POTENTIAL FOR SHOWERS THROUGH THE DAY APPEARS TO BE IN OUR FAR SOUTHEAST WHERE DEEP ISENTROPIC LIFT PERSISTS THROUGH MUCH OF THE DAY. DEPTH OF MOISTURE A BIT OF A CONCERN AND HAVE TRIMMED BACK RAINFALL AMOUNTS A BIT FROM PREVIOUS FORECAST FOR TODAY...WITH AROUND A TENTH OF AN INCH OR A LITTLE MORE ALONG/SOUTHEAST OF HIGHWAY 60 CORRIDOR...AND LESS THAN A TENTH ELSEWHERE IN THE CWA. AS FOR TEMPERATURES...HOLDING A FEW DEGREES COOLER THAN THURSDAY IN THE EAST DUE TO THICKER CLOUD COVER AND PRECIP CHANCES...BUT A SHADE WARMER WEST WHERE 925MB TEMPERATURES ARE FORECAST TO CLIMB A DEGREE OR TWO HIGHER THAN THURSDAY IN THERMAL RIDGE JUST AHEAD OF THE SURFACE BOUNDARY. WITH THE WARMER TEMPERATURES AND BETTER LOW LEVEL MOISTURE WEST...BEGIN TO SEE BETTER SURFACE BASED INSTABILITY AND LEADING TO POSSIBLE ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT IN OUR FAR WEST BY LATE AFTERNOON. GFS/NAM SHOWING SBCAPE VALUES REACHING 1000-1500 J/KG...BUT RAP CONSIDERABLY LOWER DUE TO WARMER MID-UPPER LEVEL TEMPERATURES. IF GFS/NAM PROFILES PAN OUT...CANNOT ARGUE WITH SPC MARGINAL THREAT FOR HAIL IN OUR SOUTHWEST CWA LATE THIS AFTERNOON/EVENING. FOR TONIGHT...UPPER TROUGH SWINGING OUT OF THE CENTRAL ROCKIES SHOULD BRING INCREASING THREAT OF RAIN TO OUR SOUTHEAST AS IT STRENGTHENS AND SLIDES EAST THROUGH THE CENTRAL PLAINS. QUESTION IS HOW FAR NORTH THE PRECIP SHIELD WILL EXPAND BEFORE THE WAVE PULLS EAST LATE TONIGHT. FOR NOW HAVE EXPANDED LIKELY POPS A BIT FARTHER NORTH...TO NEAR A VERMILLION-WORTHINGTON LINE...WITH MORE WIDESPREAD ACTIVITY SOUTH OF SIOUX CITY-SPENCER. PRECIP AMOUNTS AGAIN EXPECTED TO REMAIN ON THE LIGHTER SIDE...AROUND A TENTH OR TWO OVER NORTHWEST IOWA AND MUCH LESS FOR MOST OF SOUTHEAST SOUTH DAKOTA AND SOUTHWEST MINNESOTA. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 415 AM CDT FRI APR 24 2015 ON SATURDAY MORNING...IT IS UNCLEAR HOW FAR TO EXTEND POPS FROM NORTHWEST IOWA BACK TO THE WEST. MOST MODELS SUGGEST POPS ACROSS NORTHWEST IOWA...BUT SOLUTIONS VARY TO THE WEST AS LIMITED DYNAMICS AND RELATIVELY SHALLOW MOISTURE LIMIT PRECIPITATION POTENTIAL. WITH EASTERLY FLOW CONTINUING THROUGH THE DAY...KEPT TEMPERATURES BELOW NORMAL IN THE EAST WITH WARMER HIGHS ACROSS SOUTH CENTRAL SOUTH DAKOTA. MODELS SHOW SWATH OF DRIER AIR WORKING INTO THE REGION ON SUNDAY FROM THE EAST. WITH RELATIVELY DRY AIR...WENT AHEAD AND LOWERED DEW POINTS AND SKY COVER AND RAISED TEMPERATURES. THIS ONCE AGAIN WILL CREATE ELEVATED FIRE WEATHER CONCERNS THOUGH WITH WINDS ALOFT ONLY IN THE 15-20 KNOTS RANGE...AM NOT EXPECTING WINDS TO GET STRONG ENOUGH FOR RED FLAG. MONDAY LOOKS TO BE A RELATIVELY PLEASANT DAY ACROSS THE AREA WITH WEAK WINDS AHEAD OF A FRONT MOVING THROUGH MONDAY EVENING. LEFT SOME SLIGHT CHANCE POPS ACROSS THE NORTH WITH THE FRONTAL PASSAGE. CONSIDERED REMOVING POPS ALL TOGETHER AS MOISTURE REMAINS QUITE LIMITED. LOOKS TO BE YET ANOTHER DRY WEEK ACROSS THE REGION. UPPER LEVEL JET BUCKLES TO THE NORTH LEADING TO A WARMING TREND. WINDS APPEAR TO INCREASE LATE IN THE WEEK...POTENTIALLY CREATING ADDITIONAL FIRE WEATHER CONCERNS LATE NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1101 PM CDT THU APR 23 2015 ALTHOUGH VFR IS PREVAILING RIGHT NOW...THE NAM MODEL SOUNDINGS AND HUMIDITY TIME SECTIONS ARE STILL SHOWING A DETERIORATION OF CEILINGS INTO THE MVFR CATEGORY FROM SOUTH TO NORTH BETWEEN 06Z AND 12Z THIS MORNING. THE MVFR SCENARIO BECOMES MORE ENTRENCHED ON FRIDAY AND FRIDAY EVENING...EXCEPT PERHAPS AT KHON WHO MAY BE IN THE LOWER END VFR CATEGORY FOR A BULK OF FRIDAY. FOR NOW...ONLY HAVE THE MENTION OF SHOWERS IN THE TAF FORECASTS. CONDITIONS ARE STABLE FROM THE SURFACE TO ALMOST 700MB. THERE IS MID LEVEL INSTABILITY BETWEEN 700-500MB SO IF ANY PRECIPITATION WOULD HAPPEN TO TAP INTO THAT AIR...THEN SOME ISOLATED THUNDERSTORMS ARE POSSIBLE. BUT AT THIS TIME...THUNDER CHANCES LOOK TOO SKITTISH TO MENTION IN THE FORECASTS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM...JH LONG TERM... AVIATION...MJ
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1149 PM CDT THU APR 23 2015 .UPDATE... UPDATED FOR THE 06Z AVIATION DISCUSSION && .PREV DISCUSSION... /ISSUED 942 PM CDT THU APR 23 2015/ DISCUSSION... COOL HIGH PRESSURE HAS SETTLED OVER THE REGION WITH HIGH CLOUDS STREAMING IN FROM THE WEST. TEMPS ARE IN THE 50S WITH LIGHT WINDS. NOT MUCH CHANGE OVERNIGHT. TEMPS WILL FALL A FEW DEGREES AND THE LATEST HRRR IS BRINGING SOME SHRAS TOWARD THE AREA LATE AS THE WARM FRONT STARTS LIFTING NORTH. CURRENT FORECAST ON TRACK. NO CHANGES NEEDED. SJM PREV DISCUSSION... /ISSUED 239 PM CDT THU APR 23 2015/ CURRENTLY THE MIDSOUTH WAS PARTLY TO MOSTLY CLOUDY WITH A FEW SPRINKLES STILL LINGERING ON RADAR ACROSS THE SOUTHERN COUNTIES OF NORTH MISSISSIPPI. TEMPERATURES WERE IN THE LOW TO MID 60S...WITH NORTH TO NORTHEAST WINDS RANGING FROM 5 TO 10 KTS. ONLY AN ADDITIONAL DEGREE OR TWO OF WARMING IS EXPECTED TODAY. FOR TONIGHT...REDUCED RAIN CHANCES TONIGHT AND KEPT THEM MAINLY WEST OF THE MISSISSIPPI RIVER AS MODELS HAVE SLOWED THE ONSET OF A LIFTING WARM FRONT. SKIES HOWEVER WILL REMAIN MOSTLY CLOUDY OVER MOST OF THE REGION...KEEPING TEMPERATURES A BIT MILDER. FRIDAY AND SATURDAY...CURRENT TROUGH ACROSS THE SOUTHWEST STATES IS PROGGED TO ADVANCE NORTHEAST TO THE MID MISSISSIPPI VALLEY... WHILE A SURFACE LOW IN WESTERN KANSAS TRACKS TO THE OHIO RIVER. THIS SYSTEM IS FORECASTED TO UNDERGO DEEPENING INITIALLY FRIDAY AND FRIDAY NIGHT...AND THEN MAINTAIN STEADY STRENGTH ON SATURDAY. A WARM FRONT WILL LIFT NORTH THROUGH THE MIDSOUTH WITH THE THREAT FOR SHOWERS AND STORMS INCREASING THROUGHOUT THE DAY. BEST CHANCES FOR RAIN THOUGH WILL ARRIVE FRIDAY EVENING WITH EMBEDDED ELEVATED THUNDER. QUESTIONS ARISE AFTER MIDNIGHT IF STORMS CAN REFORM NEAR THE BOUNDARY OR IN THE WARM SECTOR. INSTABILITY APPEARS WEAK BUT SHEAR IS STRONG. SO AN ISOLATED LARGE HAIL OR DAMAGING WIND REPORT COULD MATERIALIZE...ESPECIALLY ACROSS THE WEST. BY MID MORNING SATURDAY A SURGING DRY SLOT WILL BEGIN SHOVING THE LOW LEVEL MOISTURE INTO MIDDLE TENNESSEE AND NORTHERN ALABAMA. THE MIDSOUTH COUNTIES WILL HAVE A SMALL WINDOW FOR SEVERE WEATHER AROUND MIDDAY. THESE STORMS WOULD HAVE A BETTER POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS AS CAPE CLIMBS TO NEAR 2500 J/KG AND LI`S DROP TO -9C. UNLESS THE SYSTEM SLOWS CONSIDERABLY THE BEST THREAT ON SATURDAY WILL BE EAST OF THE MEMPHIS METRO. THE DRY SLOT WILL PROVIDE FOR GUSTY WINDS...WITH THE STRONG MIXING PROVIDING HIGHS IN THE 80S. THE DELTA COUNTIES MAY NEED A WIND ADVISORY SATURDAY AFTERNOON. A WEAK COLD FRONT WILL PASS THROUGH THE MIDSOUTH SATURDAY NIGHT...BUT LIFT FROM THIS FEATURE WILL BE WEAK WITH ONLY A FEW STRAY SHOWERS POSSIBLE. SUNDAY AND SUNDAY NIGHT...SURFACE HIGH PRESSURE WILL BRIEFLY BUILD INTO THE REGION WITH DRY WEATHER AND MILDER HIGHS. MONDAY THROUGH WEDNESDAY...A SECOND TROUGH/CLOSED LOW WILL TRACK ACROSS THE SOUTHERN U.S. THE EURO AND GFS ARE BIT BETTER ALIGNED ON STORM STRENGTH AND TRACK...WITH THE GFS STILL REMAINING A BIT FASTER WITH TIMING. A COASTAL SURFACE LOW IS ANTICIPATED TO FORM AHEAD OF THE UPPER LOW. MOISTURE WILL RETURN TO THE MIDSOUTH WITH A PERSISTENT LOW LEVEL NORTH TO NORTHEAST FLOW...A MORE WINTER LIKE PATTERN. CLOUDS AND PERIODS OF RAIN WITH BELOW NORMAL TEMPERATURES ARE EXPECTED. JAB && .AVIATION... 06Z TAF CYCLE VFR CONDITIONS WILL CONTINUE INTO FRIDAY WITH CEILINGS GRADUALLY LOWERING TO MVFR LEVELS FRIDAY AFTERNOON OVER WESTERN SECTIONS OF THE FORECAST AND BY FRIDAY EVENING OVER THE EAST. SHOWERS AND THUNDERSTORMS WILL START TO MOVE INTO THE WESTERN PART OF THE FORECAST AREA BY FRIDAY AFTERNOON WITH MOST AREAS SEEING SOME RAIN FRIDAY EVENING. WINDS WILL BE MAINLY FROM THE NORTHEAST AROUND 5 KNOTS OVERNIGHT AND THEN BECOME SOUTHERLY AT 5 TO 10 KNOTS FRIDAY MORNING. ARS && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
948 AM CDT FRI APR 24 2015 .DISCUSSION... LEADING IMPULSE SUPPORTING AREA OF ELEVATED MOIST CONVECTION OVER THE NRN COUNTIES WILL CONTINUE TO QUICKLY PULL NEWD THROUGH THE DAY...AND PULL RAIN OUT OF THE AREA BY EARLY AFTERNOON. MODEST DIURNAL HEATING HAS ALLOWED AIRMASS TO BECOME MODERATELY UNSTABLE FEEDING INTO THIS COMPLEX AS OF 14Z. HOWEVER...CAPPING REMAINS IN PLACE. WITH FURTHER DIURNAL HEATING...A FEW CELLS MAY STRENGTHEN WITH PRIMARY THREATS OF BRIEF HEAVY RAIN AND SOME HAIL. WILL CONTINUE TO MONITOR RADAR TRENDS FOR THESE CELLS...ALTHOUGH CURRENT THINKING IS SVR THREAT WILL REMAIN MODEST AT BEST WITH ONGOING STORMS THROUGH THE REST OF THE MORNING WITH BRIEF HEAVY RAINFALL. MUCH OF THE AREA WILL ESSENTIALLY REMAIN BETWEEN SYSTEMS TODAY...WITH LOWER POPS THIS AFTERNOON. 12Z UA ANALYSIS/SOUNDINGS INDICATE RICH SURFACE MOISTURE FEED IS QUITE SHALLOW...WHICH WILL LIKELY KEEP RAIN CHANCES IN THE SCATTERED RANGE AT BEST FOR THE REST OF THE AFTERNOON AS AFTERNOON HEATING FURTHER WEAKENS CAP. OTHER THAN MAKING NEAR TERM CHANGES ASSOCIATED WITH ONGOING WEATHER...HAVE LEFT REST OF FORECAST THE SAME. 48 && .PREV DISCUSSION... /ISSUED 705 AM CDT FRI APR 24 2015/ AVIATION... THE BIGGEST CONCERN WILL BE THE CHANCES FOR THUNDERSTORMS TODAY. LIKED THE HRRR MODEL FOR HOW IT INITIALIZED AND CONTINUES TO DEPICT THE THUNDERSTORMS IN THE HILL COUNTRY. THE THUNDERSTORMS OCCURRING OVER THE HILL COUNTRY WERE APPROACHING KCLLAT 11Z. THE HRRR BRINGS THE BEST CHANCES FOR THUNDERSTORMS ACROSS KCLL AND KUTS THROUGH 18Z. ALTHOUGH WIDESPREAD STORMS WILL LIKELY OCCUR TO THE NORTH...BOTH KCXO AND KIAH SHOULD SEE A WINDOW OF HIGHEST CHANCES FROM ABOUT 15Z THROUGH 18Z. THE HIGH PRESSURE RIDGE OVER THE GULF WAS PROVIDING A STRONGER CAP OVER THE REMAINING SITES...ALTHOUGH THE MODELS ERODE THIS CAP LATER THIS MORNING. BECAUSE OF THIS...KHOU AND KSGR SHOULD SEE SHOWER OR THUNDER CHANCES AFTER 14Z. KLBX AND KGLS WILL HAVE A MORE DIFFICULT TIME. THE BEST CHANCES WILL LIKELY BE DURING THE MID AND LATE MORNING PERIOD AS THE REMNANTS OF A MESO-SCALE CONVECTIVE COMPLEX THAT AFFECTED SOUTH TEXAS EARLIER THIS MORNING MOVE UP THE COASTAL AREAS. THESE REMNANTS MAY PROVIDE ENOUGH LIFT FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM THROUGH MIDDAY. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 84 70 88 68 88 / 90 50 20 10 20 HOUSTON (IAH) 84 72 88 70 88 / 50 40 50 10 20 GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...48
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
705 AM CDT FRI APR 24 2015 .UPDATE... SENT AN UPDATE FOR THE MARINE WINDS FOR THIS MORNING. THE REMNANTS OF THE MESOSCALE CONVECTIVE COMPLEX THAT AFFECTING DEEP SOUTH TEXAS EARLIER THIS MORNING SHOULD MOVE UP THE COAST THIS MORNING. THESE MAY GENERATE ISOLATED SHOWERS AND THUNDERSTORMS AND GUSTY WINDS. 40 && .PREV DISCUSSION... /ISSUED 632 AM CDT FRI APR 24 2015/ DISCUSSION... SEE THE 12Z AVIATION DISCUSSION BELOW. 40 AVIATION... THE BIGGEST CONCERN WILL BE THE CHANCES FOR THUNDERSTORMS TODAY. LIKED THE HRRR MODEL FOR HOW IT INITIALIZED AND CONTINUES TO DEPICT THE THUNDERSTORMS IN THE HILL COUNTRY. THE THUNDERSTORMS OCCURRING OVER THE HILL COUNTRY WERE APPROACHING KCLLAT 11Z. THE HRRR BRINGS THE BEST CHANCES FOR THUNDERSTORMS ACROSS KCLL AND KUTS THROUGH 18Z. ALTHOUGH WIDESPREAD STORMS WILL LIKELY OCCUR TO THE NORTH...BOTH KCXO AND KIAH SHOULD SEE A WINDOW OF HIGHEST CHANCES FROM ABOUT 15Z THROUGH 18Z. THE HIGH PRESSURE RIDGE OVER THE GULF WAS PROVIDING A STRONGER CAP OVER THE REMAINING SITES...ALTHOUGH THE MODELS ERODE THIS CAP LATER THIS MORNING. BECAUSE OF THIS...KHOU AND KSGR SHOULD SEE SHOWER OR THUNDER CHANCES AFTER 14Z. KLBX AND KGLS WILL HAVE A MORE DIFFICULT TIME. THE BEST CHANCES WILL LIKELY BE DURING THE MID AND LATE MORNING PERIOD AS THE REMNANTS OF A MESO-SCALE CONVECTIVE COMPLEX THAT AFFECTED SOUTH TEXAS EARLIER THIS MORNING MOVE UP THE COASTAL AREAS. THESE REMNANTS MAY PROVIDE ENOUGH LIFT FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM THROUGH MIDDAY. 40 PREV DISCUSSION... /ISSUED 547 AM CDT FRI APR 24 2015/ UPDATE... RAISING POPS PER RADAR TRENDS. DISCUSSION... WILL RAISE POPS FOR THIS MORNING AS CONVECTION IS FIRING ALONG A WEAK 850 MB BOUNDARY. CONVECTION IS BACK BUILDING TO THE E-SE IN LESS MODIFIED AIR. NEW ZONES OUT SHORTLY. 43 PREV DISCUSSION... /ISSUED 401 AM CDT FRI APR 24 2015/ DISCUSSION... AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT. MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED 2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850 MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700 MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST. AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF. MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z. THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000 AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE 850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE ENTIRE AREA. PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20 POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF THE FRONT. 43 MARINE... ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY AFTERNOON AND PERSIST INTO TUESDAY NIGHT. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20 HOUSTON (IAH) 84 72 88 70 88 / 50 40 50 10 20 GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...43 AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
632 AM CDT FRI APR 24 2015 .DISCUSSION... SEE THE 12Z AVIATION DISCUSSION BELOW. 40 && .AVIATION... THE BIGGEST CONCERN WILL BE THE CHANCES FOR THUNDERSTORMS TODAY. LIKED THE HRRR MODEL FOR HOW IT INITIALIZED AND CONTINUES TO DEPICT THE THUNDERSTORMS IN THE HILL COUNTRY. THE THUNDERSTORMS OCCURRING OVER THE HILL COUNTRY WERE APPROACHINGKCLL AT 11Z. THE HRRR BRINGS THE BEST CHANCES FOR THUNDERSTORMS ACROSS KCLL AND KUTS THROUGH 18Z. ALTHOUGH WIDESPREAD STORMS WILL LIKELY OCCUR TO THE NORTH...BOTH KCXO AND KIAH SHOULD SEE A WINDOW OF HIGHEST CHANCES FROM ABOUT 15Z THROUGH 18Z. THE HIGH PRESSURE RIDGE OVER THE GULF WAS PROVIDING A STRONGER CAP OVER THE REMAINING SITES...ALTHOUGH THE MODELS ERODE THIS CAP LATER THIS MORNING. BECAUSE OF THIS...KHOU AND KSGR SHOULD SEE SHOWER OR THUNDER CHANCES AFTER 14Z. KLBX AND KGLS WILL HAVE A MORE DIFFICULT TIME. THE BEST CHANCES WILL LIKELY BE DURING THE MID AND LATE MORNING PERIOD AS THE REMNANTS OF A MESO-SCALE CONVECTIVE COMPLEX THAT AFFECTED SOUTH TEXAS EARLIER THIS MORNING MOVE UP THE COASTAL AREAS. THESE REMNANTS MAY PROVIDE ENOUGH LIFT FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORM THROUGH MIDDAY. 40 && .PREV DISCUSSION... /ISSUED 547 AM CDT FRI APR 24 2015/ UPDATE... RAISING POPS PER RADAR TRENDS. DISCUSSION... WILL RAISE POPS FOR THIS MORNING AS CONVECTION IS FIRING ALONG A WEAK 850 MB BOUNDARY. CONVECTION IS BACKBUILDING TO THE E-SE IN LESS MODIFIED AIR. NEW ZONES OUT SHORTLY. 43 PREV DISCUSSION... /ISSUED 401 AM CDT FRI APR 24 2015/ DISCUSSION... AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT. MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED 2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850 MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700 MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST. AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF. MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z. THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000 AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE 850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE ENTIRE AREA. PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20 POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF THE FRONT. 43 MARINE... ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY AFTERNOON AND PERSIST INTO TUESDAY NIGHT. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20 HOUSTON (IAH) 84 72 88 70 88 / 50 40 50 10 20 GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...43 AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
547 AM CDT FRI APR 24 2015 .UPDATE... RAISING POPS PER RADAR TRENDS. && .DISCUSSION... WILL RAISE POPS FOR THIS MORNING AS CONVECTION IS FIRING ALONG A WEAK 850 MB BOUNDARY. CONVECTION IS BACKBUILDING TO THE E-SE IN LESS MODIFIED AIR. NEW ZONES OUT SHORTLY. 43 && .PREV DISCUSSION... /ISSUED 401 AM CDT FRI APR 24 2015/ DISCUSSION... AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT. MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED 2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850 MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700 MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST. AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF. MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z. THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000 AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE 850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE ENTIRE AREA. PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20 POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF THE FRONT. 43 MARINE... ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY AFTERNOON AND PERSIST INTO TUESDAY NIGHT. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20 HOUSTON (IAH) 84 72 88 70 88 / 40 40 50 10 20 GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...43
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
401 AM CDT FRI APR 24 2015 .DISCUSSION... AT 2 AM...A WEAK SURFACE TROUGH EXTENDED FROM ABOUT TYLER TO HONDO TO DEL RIO. A WEAK MESO-HIGH WAS LOCATED NEAR SAN ANGELO. RADAR SHOWS A DECAYING MCS OVER DEEP SOUTH TEXAS. THIS FEATURE COULD SEND A PATCH OF LIGHT RAIN INTO THE SOUTHWEST ZONES THIS MORNING BUT WILL PROBABLY SEND A WEAK BOUNDARY THAT COULD SERVE AS A FOCUS FOR SHRA/TSRA DEVELOPMENT LATER THIS MORNING. FURTHER WEST...A CLUSTER OF STRONG STORMS IN DIMMIT AND LA SALLE COUNTIES IS MOVING E-NE AND WILL BE APPROACHING SE TX BETWEEN 13-14Z. NOT SURE THESE STORMS WILL HOLD TOGETHER BUT AGAIN COLD SEND OFF AN OUTFLOW TO SERVE AS FOCUS FOR ADDITIONAL DEVELOPMENT. MOISTURE LOOKS PLENTIFUL TODAY WITH PW VALUES PROGGED TO EXCEED 2.00 INCHES OVER PARTS OF SE TX. 850 MB TD AT BRO WAS 17 C AND 15C AT CRP AT 00Z. THERE ALSO LOOKS LIKE THERE IS A WEAK TROUGH AT 850 MB EXTENDING THE LOUISIANA COAST TO AROUND LAREDO. THERE IS ALSO EVIDENCE OF WEAK 850 MB HIGH PRESSURE OVER THE WESTERN GULF. 700 MB LOOKS DRY WITH MORE PRONOUNCED RIDGING ALONG THE TEXAS COAST. AT 250 MB...A RIBBON OF FASTER SPEEDS EXTENDED ACROSS THE TENNESSEE VALLEY AND A SECONDARY SPEED MAX NEAR EL PASO. WEAK RIDGING WAS AGAIN NOTED OVER THE WESTERN GULF. MODELS NOT IN THE BEST AGREEMENT TODAY OF WHEN AND WHERE CONVECTION WILL DEVELOP. THE TEXAS TECH WRF DID NOT INITIALIZE WELL BUT IT SEEMS TO BE HANDLING THE CONVECTION OVER SW TX FAIRLY WELL WHILE THE HRRR AND RAP SEEMED TO INITIALIZE WELL AT 08Z. THE JET STRUCTURE DOES NOT LOOK FAVORABLE TODAY WITH THE BEST DIVERGENCE OVER NORTH TEXAS BUT SE TX REMAINS VERY UNSTABLE AND FCST SOUNDINGS SHOW TREMENDOUS INSTABILITY WITH CAPES AOA 3000 AND LI VALUES -10 AND LAPSE RATES ABOVE 7.0. HOWEVER THIS INSTABILITY NEEDS TO BE TAPPED BY A PASSING S/WV OR SOME KIND OF SFC TRIGGER AND THIS IS WHERE THINGS BECOME LESS CLEAR. OTHER THAN OUTFLOW BOUNDARIES...JUST CAN`T FIND A WELL DEFINED CATALYST TO TRIGGER SHRA/TSRA. THE OTHER CONCERN REGARDING CONVECTION IS THE 850-500 RIDGE OVER THE GULF THAT IS IMPINGING ON SE TX. AM A BIT NERVOUS THAT THIS FEATURE WILL IMPART A BIT OF SUBSIDENCE ALONG THE COAST AND SHUNT MUCH OF TODAYS PRECIP TO THE WEST. WILL MAINTAIN LIKELY POPS OVER THE NORTH AND CHANCE POPS CENTRAL. WILL ALSO MAINTAIN SEVERE WORDING OVER THE NORTH BUT YOU CAN`T RULE A SEVERE STORM ANYWHERE IN THE CWA AS INSTABILITY IS IMPRESSIVE OVER THE ENTIRE AREA. PRECIPITATION POTENTIAL WILL INCREASE AGAIN TONIGHT INTO EARLY SATURDAY AS SE TX LIES IN A RRQ FOR A TIME. THE SPEED MAX WILL EXIT BY LATE SATURDAY MORNING AND RAIN WILL DIMINISH QUICKLY WITH A W-SW SFC WIND DEVELOPING. CLOUDS WILL BREAK IN THE AFTN AND WITH A W-SW WIND...AM EXPECTING TEMPS TO WARM UP QUICKLY. SUNDAY STILL LOOKS IFFY AS WINDS ALOFT STAY OUT OF THE SW. WILL INTRODUCE 20 POPS FOR SUNDAY. BY SUNDAY NIGHT...AN UPPER LEVEL LOW WILL APPROACH TX FROM THE WEST. THIS FEATURE WILL TRIGGER ANOTHER ROUND OF SHRA/TSRA SUN NITE INTO MON NITE. SOME OF THE STORMS COULD AGAIN BE STRONG. A COLD FRONT WILL CROSS THE COAST ON TUES MORNING. MUCH COOLER AND DRIER WEATHER IS EXPECTED IN THE WAKE OF THE FRONT. 43 && .MARINE... ONSHORE WINDS WILL PERSIST THROUGH THE WEEKEND. THERE IS A SLIGHT CHANCE FOR THUNDERSTORMS TODAY...WITH BETTER CHANCES LATE TONIGHT INTO SATURDAY. A COLD FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY TUESDAY. MODERATE TO STRONG OFFSHORE WINDS FOLLOWING THE FRONTAL PASSAGE MAY REACH INTO ADVISORY CRITERIA AS EARLY AS TUESDAY AFTERNOON AND PERSIST INTO TUESDAY NIGHT. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 84 70 88 68 88 / 60 50 20 10 20 HOUSTON (IAH) 84 72 88 70 88 / 40 40 50 10 10 GALVESTON (GLS) 78 73 83 73 80 / 30 40 50 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
342 PM CDT FRI APR 24 2015 .TONIGHT AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM. AREA OF RAIN SHOWERS EXTENDS FROM NORTH CENTRAL IOWA AND SOUTHEAST MINNESOTA INTO SOUTH CENTRAL WISCONSIN. THIS IS IN RESPONSE TO 700 MB WARM AIR ADVECTION AND FRONTOGENESIS RESPONSE...AS WELL AS FROM AN ADVANCING 500 MB VORTICITY MAXIMUM. THESE FEATURES SHOULD CONTINUE TO SLIDE EAST NORTHEAST ACROSS THE AREA INTO EARLY THIS EVENING...SPREADING LIGHT TO MODERATE RAIN SHOWERS THROUGH THE AREA. STRENGTH OF UPWARD VERTICAL MOTION SHOULD OVERCOME DRY LOW LEVELS BELOW 5000 FEET ABOVE GROUND LEVEL DURING THIS TIME. RAP SOUNDINGS SHOWING WEAK ELEVATED CAPE...LITTLE TO NONE ON OTHER MODELS...SO WILL NOT INCLUDE THUNDER MENTION. 500 MB SHORTWAVE TROUGH SLIDES EAST SOUTHEAST FROM NORTHWEST MISSOURI TO CENTRAL ILLINOIS SATURDAY. MODELS HAVE BEEN TRENDING SLIGHTLY SOUTHWARD WITH THE BEST UPWARD VERTICAL MOTION ASSOCIATED WITH THE SHORTWAVE AND LOW TO MID LEVEL FRONTOGENESIS/Q VECTOR CONVERGENCE. THUS...THE QPF SHIELD IN THE MODELS HAS TRENDED A BIT SOUTHWARD AS WELL. AREA FORECAST SOUNDINGS STILL SHOWING A FAIR AMOUNT OF DEEP MOISTURE IN THE SOUTH LATER TONIGHT INTO SATURDAY...LESS SO IN THE FAR NORTHERN COUNTIES. LOOKS TO BE A NORTH TO SOUTH GRADIENT IN THE POPS FOR THIS SYSTEM...WITH SOME UNCERTAINTY WITH THE SYSTEM TRACK. CONTINUED HIGH POPS IN THE SOUTHERN 2/3 OF THE AREA SATURDAY...WITH CHANCE POPS IN THE FAR NORTH. EAST NORTHEAST WINDS ARE EXPECTED TO GRADUALLY INCREASE IN MAGNITUDE TONIGHT...WITH GUSTY EAST NORTHEAST WINDS SATURDAY. THIS WILL MAKE FOR A RAW DAY WITH THE RAIN. LOWS TONIGHT WILL DROP INTO THE UPPER 30S TO AROUND 40...WITH HIGHS ONLY IN THE 40S SATURDAY WITH THE CLOUDS AND RAIN. .SATURDAY NIGHT THROUGH MONDAY...FORECAST CONFIDENCE HIGH. ANY LINGERING PRECIPITATION WILL COME TO AN END SATURDAY EVENING AS A SHORTWAVE IMPULSE AND ASSOCIATED SFC LOW TRACK EASTWARD THROUGH THE OHIO VALLEY. UPSTREAM 500 MB HEIGHTS BEGIN RISING OVER MINNESOTA ON SATURDAY NIGHT...WITH THE MID-LEVEL RIDGE AXIS BECOMING ORIENTED FROM THE CENTRAL PLAINS NORTHEASTWARD INTO SOUTHERN ONTARIO BY MONDAY. THIS WILL SUPPORT SFC RIDGING THAT BUILDS INTO THE WESTERN GREAT LAKES AND UPPER MIDWEST REGIONS ON SUNDAY NIGHT INTO MONDAY. LOW-LEVEL COLD ADVECTION AND NORTHEASTERLY FLOW OFF THE LAKE WILL KEEP TEMPERATURES RELATIVELY COOL ON SUNDAY. 925 MB TEMPERATURES IN THE 3 TO 8C RANGE SUPPORT HIGHS IN THE 50S TO NEAR 60 AWAY FROM THE LAKESHORE. WITH NEAR NEUTRAL LOW-LEVEL THERMAL ADVECTION AND NORTHERLY FLOW ON MONDAY EXPECT READINGS TO WARM A BIT MORE ACROSS THE WEST. PERSISTENT EASTERLY WIND COMPONENT WILL ONCE AGAIN PREVAIL FOR THE EASTERN CWA ON MONDAY...KEEPING THE LAKESHORE COMMUNITIES COOLER. .TUESDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE MEDIUM. MID-LEVEL RIDGING INITIALLY OVER THE EASTERN GREAT LAKES REGION SHIFTS EAST INTO NEW ENGLAND THROUGH WEDNESDAY AS SHORTWAVE ENERGY ADVANCES FROM THE NORTHERN/CENTRAL PLAINS INTO THE EASTERN GREAT LAKES AND MISSISSIPPI VALLEY REGIONS. SOME UNCERTAINTY REGARDING SHORTWAVE EVOLUTION TUESDAY NIGHT...WITH DETERMINISTIC 00Z ECMWF BRINGING A MORE PROGRESSIVE AND STRONGER WAVE THROUGH SOUTHERN WISCONSIN THAN THE 06Z GFS. 12Z ECMWF RUN APPEARS SLOWER...AND EVOLVES A CLOSED LOW OVER LAKE MICHIGAN ON WEDNESDAY. SOME LIGHT PCPN IS POSSIBLE TUESDAY NIGHT OR WEDNESDAY...BUT OVERALL FORCING FOR ASCENT APPEARS WEAK. WARMING 925 MB TEMPERATURES OF 9-12C SUPPORT HIGHS POTENTIALLY REACHING WELL INTO THE 60S AWAY FROM THE LAKE. .THURSDAY THROUGH FRIDAY...FORECAST CONFIDENCE MEDIUM. MID-LEVEL RIDGE AXIS SETS UP OVER THE NORTHERN PLAINS WITH WEAK SFC RIDGING KEEPING THINGS QUIET ACROSS THE CWA FOR THURSDAY INTO FRIDAY AFTERNOON. THEREAFTER...MODEL DIFFERENCES IN THE TIMING/STRENGTH OF A SHORTWAVE IMPULSE PASSING THROUGH SOUTHERN CANADA SUGGEST ADDING SLIGHT CHANCE POPS FOR AREA FRIDAY NIGHT. SOME UNCERTAINTY REGARDING TEMPERATURES DURING THE PERIOD...AND DID NOT DEVIATE FROM MODEL BLENDED CONSENSUS VALUES. && .AVIATION/00Z TAFS/... LIGHT TO MODERATE BAND OF RAIN SHOWERS SHOULD CONTINUE TO MOVE EAST NORTHEAST THROUGH THE AREA THROUGH EARLY THIS EVENING. VFR CONDITIONS SHOULD REMAIN DURING THIS TIME. EAST/SOUTHEAST WINDS WILL BECOME EAST NORTHEAST BY MIDDLE TO LATE EVENING...GRADUALLY INCREASING IN STRENGTH LATER TONIGHT. A LULL IN THE SHOWER ACTIVITY SHOULD OCCUR LATER THIS EVENING AND INTO THE OVERNIGHT HOURS...UNTIL MAIN TROUGH OF LOW PRESSURE SLIDES EAST SOUTHEAST FROM NORTHWEST MISSOURI INTO CENTRAL ILLINOIS SATURDAY. AREA OF LIGHT TO MODERATE RAIN SHOULD SPREAD ACROSS TAF SITES BETWEEN 10Z AND 14Z SATURDAY...LINGERING THROUGH THE DAY. EAST TO EAST NORTHEAST WINDS WILL REMAIN MODERATE IN STRENGTH SATURDAY...WITH GUSTS TO AROUND 24 KNOTS. EXPECT MAINLY MVFR CEILINGS AND VISIBILITIES WITH THE RAIN. SOME IFR VISIBILITIES AND CEILINGS ARE POSSIBLE TOWARD KENOSHA...REMAINING ABOVE ALTERNATE MINIMUMS. && .MARINE... EAST NORTHEAST WINDS ARE EXPECTED TO GATHER STRENGTH TONIGHT INTO SATURDAY...BECOMING NORTHEAST SATURDAY NIGHT. GUSTS TO 25 KNOTS ARE EXPECTED SATURDAY INTO SATURDAY NIGHT...WITH TIGHT PRESSURE GRADIENT FROM PASSING LOW PRESSURE TO THE SOUTH. ONSHORE FLOW WILL BUILD WAVE HEIGHTS INTO THE 3 TO 6 FOOT RANGE FOR THE NEARSHORE WATERS. A SMALL CRAFT ADVISORY WILL BE NEEDED FOR SATURDAY AND SATURDAY NIGHT. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY FROM 7 AM SATURDAY TO 7 AM CDT SUNDAY FOR LMZ645-646. SMALL CRAFT ADVISORY FROM 10 AM SATURDAY TO 7 AM CDT SUNDAY FOR LMZ643-644. && $$ TONIGHT/SATURDAY AND AVIATION/MARINE...WOOD SATURDAY NIGHT THROUGH FRIDAY...SPM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
222 PM CDT FRI APR 24 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 222 PM CDT FRI APR 24 2015 AS WAVE EJECTS OUT OF SOUTHWEST U.S. MAIN FOCUS IN SHORT TERM IS RAIN THREAT...ESPECIALLY ON SATURDAY AS SYNOPTIC SURFACE LOW PASSES BY TO THE SOUTH. WEAKER INITIAL SHORT WAVE TROUGH SWINGING THROUGH AREA THIS AFTERNOON HAS GENERATED BROAD RAIN SHIELD WITH SOME WARM AIR ADVECTION. CONSIDERABLY DRIER AIR IN CENTRAL AND EASTERN WISCONSIN WILL BATTLE THIS. AS FORCING SHIFTS EAST THIS EVENING...BULK OF RAIN SHOULD END BY EARLY EVENING WITH ONLY PATCHY THREAT AFTER THAT. THIS TREND IS SUPPORTED IN HIGH RESOLUTION MODELS AND HAVE ADJUSTED RAIN CHANCES DOWNWARD TO ACCOUNT FOR THAT. AS STRONGER MAIN WAVE EJECTS INTO CENTRAL U.S. TONIGHT...WITH STRONGER...DEEPER Q-G FORCING...EXTENSIVE AREA OF RAIN AND THUNDERSTORMS WILL FORM ACROSS PARTS OF THE CORNBELT AND MID MISSISSIPPI RIVER VALLEY. BETTER AGREEMENT IN 24.12Z MODELS WITH HOW FAR NORTH PRECIPITATION WILL GET WHILE SOME MODELS HAVE BEEN VERY CONSISTENT KEEPING RAIN SOUTH OF INTERSTATE 90 CONSISTENTLY. THIS WILL MEAN A TIGHT NORTH-SOUTH GRADIENT IN RAIN CHANCES MAINLY SATURDAY MORNING BEFORE SYSTEM EXITS BY LATE AFTERNOON. AS SURFACE LOW SHIFTS EAST...COULD ALSO SEE INCREASING EAST TO NORTHEAST WINDS PICK UP DRIER AIR TO THE NORTHEAST WHICH WOULD ALSO BATTLE NORTHWARD EXTENT OF PRECIPITATION. HAVE TRIED TO TIGHTEN THIS RAIN THREAT GRADIENT UP WITH UP TO AN INCH OF RAIN POSSIBLE CLOSER TO HIGHWAY 20 IN IOWA...TO NOTHING NORTH OF INTERSTATE 90. NIL TO MINIMAL CAPE SUGGEST THUNDER THREAT TOO LOW TO MENTION THIS FAR NORTH. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 222 PM CDT FRI APR 24 2015 SHORT TERM UPPER RIDGE WILL BUILD IN QUICKLY SATURDAY NIGHT AS RAIN THREAT ENDS AND SKIES CLEAR OUT. THIS WILL LAST INTO EARLY NEXT WEEK WITH QUIET WEATHER ON TAP AND WARMING TEMPERATURES...CLOSER TO NORMALS FOR LATE APRIL. UPPER FLOW ACROSS U.S. BECOMES FAR MORE MESSY NEXT WEEK WITH LARGE LOW OFF OF NORTHEAST AND SPLIT FLOW DEVELOPS IN WEST. THIS COULD LEAVE OUR REGION IN FAIRLY QUIET PATTERN BETWEEN ALL THIS. MEDIUM RANGE GUIDANCE SUGGESTS WEAK WAVE COULD DRAG COLD FRONT INTO AREA NEXT TUESDAY WITH MINOR RAIN THREAT BUT BESIDES THAT...MORE SIGNALS FOR RIDGING AND NICE SPRING WEATHER. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1259 PM CDT FRI APR 24 2015 INITIAL ROUND OF SHOWERS MOVING ACROSS THE AREA IN A REGION OF SOME ISENTROPIC UP GLIDE AND FRONTOGENESIS IN THE 1000-700 MB LAYER. THESE HAVE BEEN ABLE TO PRODUCE SOME SHORT PERIODS OF MVFR CONDITIONS. LOOKING AT THE 24.15Z HRRR AND 24.18Z NAM...THESE SHOWERS WILL CONTINUE TO PROGRESS NORTHEAST BUT WILL HAVE A TOUGH TIME GETTING VERY FAR INTO WESTERN WISCONSIN WHERE DEW POINTS HAVE REMAINED IN THE TEENS. PLAN TO SHOW TEMPO GROUPS FOR BOTH TAF SITES THROUGH THE MIDDLE OF THE AFTERNOON WITH THE SHOWERS AROUND AND THE POTENTIAL FOR MVFR CONDITIONS. AFTER THAT...THE FORCING BEGINS TO REFOCUS FARTHER TO THE SOUTH WITH THE FRONTOGENESIS FOCUSING OVER EXTREME SOUTHERN WISCONSIN INTO IOWA AS THE MAIN SURFACE LOW TRACKS ACROSS KANSAS INTO MISSOURI. THIS SHOULD TAKE MOST OF THE RAIN SOUTH OF BOTH TAF SITES AND WENT BACK TO JUST VCSH FOR THE LATE AFTERNOON INTO THE EARLY EVENING. AFTER THAT...THINK THE ACTIVITY WILL BE TO THE SOUTH AND HAVE GONE DRY FOR THE REMAINDER OF THE PERIOD. WITH THE LOW LEVEL FLOW TURNING MORE TO THE EAST...THIS WILL HELP TO BRING IN THE LOW LEVEL DRY AIR WHICH SHOULD SERVE TO KEEP CEILINGS VFR ONCE THE SHOWERS ARE OUT OF THE AREA. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...SHEA LONG TERM...SHEA AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
100 PM CDT FRI APR 24 2015 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 245 AM CDT FRI APR 24 2015 A 500 MB LOW TROUGH IS SLATED TO MOVE NORTHEAST OUT OF THE DESERT SOUTHWEST...MOVING ACROSS THE MID MISSISSIPPI RIVER VALLEY BY 18Z SAT. THE TROUGH/S ASSOCIATED SFC LOW WILL HOLD WITH THE TROUGH...MOVING FROM THE SOUTHERN PLAINS TOWARD THE OH RIVER VALLEY BY 00Z SUN. WHILE THE HEART OF THE SYSTEM WILL STAY SOUTH...OTHER PARTS WILL PROVIDE A GOOD SHOT AT SOME RAIN...ESPECIALLY FOR NORTHEAST IA/SOUTHWEST WI. FIRST...STRENGTHENING 900-800 MB FRONTOGENETIC REGION WITH A NICE NORTH-SOUTH RUNNING SWATH OF 850 MB WARM AIR ADVECTION MOVES INTO EASTERN MN THIS AFTERNOON...WEAKENING AS THEY MOVE INTO WESTERN WI TONIGHT. SOME LOW LEVEL MOISTURE TRANSPORT WITH THE THERMODYNAMICS...AND EXPECT AREAS OF SHOWERS AS A RESULT. HOWEVER...HOW FAR EAST THESE ADVANCE IS IN QUESTION. BUFKIT SOUNDINGS AND RH FIELDS POINT TO A LOT OF DRY AIR ACROSS WI...ACTING AS AN INHIBITOR TO THE RAIN/S EASTWARD MARCH. THAT...WITH WEAKENING FORCING MAKE CHANCES OVER WESTERN A BIT LESS COMPARED TO EASTERN MN. SECOND...AS THE SFC LOW MOVES SOUTH OF THE FORECAST AREA...ITS DEFORMATION REGION WITH SLOPING FRONTOGENETIC LIFT WILL EXTEND ACROSS IA AND ILL. MOISTURE WRAPS AROUND THE LOW AND THERE SHOULD BE AMPLE SATURATION FOR A BROAD AREA OF RAIN. HOW FAR NORTH THE BEST RAIN CHANCES EXTEND IS THE BIGGEST QUESTION...AND NAM/GFS/EC ALL SEEM TO FAVOR THE I-90 CORRIDOR SOUTH. LOOKS REASONABLE AT THE MOMENT. SOME SOUNDINGS SUGGEST ICE COULD BE LOST FOR A PERIOD OF TIME OVERNIGHT...MAKING DRIZZLE MORE LIKELY. GOING TO STICK WITH RAIN AS THE PTYPE. THIS AREA OF RAIN LOOKS MOST LIKELY SAT MORNING. DON/T SEE MUCH OF A THUNDER THREAT AT THIS TIME...MINIMAL IF ANY INSTABILITY...AND WHAT COULD BE THERE IS AWFULLY SKINNY. BEST CHANCES FOR ISOLATED THUNDER WOULD BE PARTS OF SOUTHEAST MN/NORTHEAST IA THIS AFTERNOON. CONFIDENCE LOW...SO GOING TO LEAVE OUT OF THE FORECAST FOR THE MOMENT. THERE COULD BE SOME SNOW IN THE NORTH...BUT CHANCES FOR PCPN ARE MUCH LESS...AND THE SUB CLOUD LAYER IS RATHER DRY...INHIBITING ANY PCPN TYPE FROM REACHING THE GROUND. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 245 AM CDT FRI APR 24 2015 THE GFS HAS TRENDED TOWARD THE EC/GEM SOLUTION OF BUILDING A SHORTWAVE UPPER LEVEL RIDGE ACROSS THE REGION FOR THE END OF THE WEEKEND. SOLUTIONS THEN FAVOR A LONG WAVE RIDGE TAKING OVER FOR NEXT WEEK...WITH VARIOUS RIDGE RUNNERS WORKING THROUGH/ACROSS IT. PLACEMENT AND TIMING OF THESE SHORTWAVE TROUGHS ARE DUBIOUS AT BEST...BUT THE VARIOUS SOLUTIONS ALL POINT TO DRY FOR THE BETTER PART OF NEXT WEEK. WITH THE SWING BACK TO RIDGING...TEMPS SHOULD FOLLOW SUIT. EXPECTING AT OR ABOVE NORMAL HIGHS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1259 PM CDT FRI APR 24 2015 INITIAL ROUND OF SHOWERS MOVING ACROSS THE AREA IN A REGION OF SOME ISENTROPIC UP GLIDE AND FRONTOGENESIS IN THE 1000-700 MB LAYER. THESE HAVE BEEN ABLE TO PRODUCE SOME SHORT PERIODS OF MVFR CONDITIONS. LOOKING AT THE 24.15Z HRRR AND 24.18Z NAM...THESE SHOWERS WILL CONTINUE TO PROGRESS NORTHEAST BUT WILL HAVE A TOUGH TIME GETTING VERY FAR INTO WESTERN WISCONSIN WHERE DEW POINTS HAVE REMAINED IN THE TEENS. PLAN TO SHOW TEMPO GROUPS FOR BOTH TAF SITES THROUGH THE MIDDLE OF THE AFTERNOON WITH THE SHOWERS AROUND AND THE POTENTIAL FOR MVFR CONDITIONS. AFTER THAT...THE FORCING BEGINS TO REFOCUS FARTHER TO THE SOUTH WITH THE FRONTOGENESIS FOCUSING OVER EXTREME SOUTHERN WISCONSIN INTO IOWA AS THE MAIN SURFACE LOW TRACKS ACROSS KANSAS INTO MISSOURI. THIS SHOULD TAKE MOST OF THE RAIN SOUTH OF BOTH TAF SITES AND WENT BACK TO JUST VCSH FOR THE LATE AFTERNOON INTO THE EARLY EVENING. AFTER THAT...THINK THE ACTIVITY WILL BE TO THE SOUTH AND HAVE GONE DRY FOR THE REMAINDER OF THE PERIOD. WITH THE LOW LEVEL FLOW TURNING MORE TO THE EAST...THIS WILL HELP TO BRING IN THE LOW LEVEL DRY AIR WHICH SHOULD SERVE TO KEEP CEILINGS VFR ONCE THE SHOWERS ARE OUT OF THE AREA. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM.....RIECK LONG TERM......RIECK AVIATION...04
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1147 AM CDT FRI APR 24 2015 .UPDATE... AREA OF RAIN SHOWERS CONTINUE TO DEVELOP ACROSS SOUTHERN MINNESOTA INTO NORTH CENTRAL AND NORTHEAST IOWA. THIS IS IN RESPONSE TO 700 MB WARM AIR ADVECTION AND FRONTOGENESIS RESPONSE...AS WELL AS FROM AN ADVANCING 500 MB VORTICITY MAXIMUM. THESE FEATURES SHOULD CONTINUE TO SLIDE EAST NORTHEAST ACROSS THE AREA THIS AFTERNOON AND EARLY THIS EVENING...BRINGING SOME LIGHT RAIN SHOWERS TO THE AREA. THE BEST SHOT WILL BE ACROSS THE SOUTHERN HALF OF THE AREA...WHERE BETTER DEEP MOISTURE SHOULD RESIDE. DRY LOW LEVELS BELOW 5000 FEET ABOVE GROUND LEVEL MAY LIMIT AREAL COVERAGE OF SHOWERS. WILL HAVE TO ADJUST POPS AFTER WATCHING TRENDS WITH THESE SHOWERS OVER THE NEXT HOUR OR SO. RAP SOUNDINGS SHOWING WEAK ELEVATED CAPE...LOWER ON OTHER MODELS...SO WILL NOT INCLUDE THUNDER MENTION AT THIS TIME. EAST SOUTHEAST WINDS WILL GRADUALLY INCREASE THIS AFTERNOON...AS WELL AS THE CLOUD COVER. HIGHS SHOULD REACH THE MIDDLE TO UPPER 50S WELL INLAND...WITH 40S NEAR LAKE MICHIGAN. WOOD && .AVIATION/18Z TAFS/... MIDDLE LEVEL CLOUDS WILL CONTINUE TO SPREAD EAST ACROSS TAF SITES THIS AFTERNOON...AS EAST SOUTHEAST WINDS GRADUALLY INCREASE. ON AND OFF LIGHT RAIN SHOWERS SHOULD MOVE EAST NORTHEAST THROUGH THE AREA LATER THIS AFTERNOON AND EARLY THIS EVENING. VFR CONDITIONS SHOULD REMAIN DURING THIS TIME. A LULL IN THE SHOWER ACTIVITY SHOULD OCCUR LATER THIS EVENING AND OVERNIGHT...UNTIL MAIN TROUGH OF LOW PRESSURE SLIDES EAST SOUTHEAST FROM IOWA INTO CENTRAL ILLINOIS LATER TONIGHT INTO SATURDAY. AREA OF LIGHT TO MODERATE RAIN SHOULD SPREAD ACROSS TAF SITES BY MID MORNING ON SATURDAY...LINGERING THROUGH THE DAY. EAST TO EAST NORTHEAST WINDS WILL REMAIN MODERATE IN STRENGTH LATER TONIGHT INTO SATURDAY. EXPECT MVFR TO SOMETIMES IFR CEILINGS AND VISIBILITIES WITH THE RAIN...REMAINING ABOVE ALTERNATE MINIMUMS. WOOD && .MARINE... EASTERLY WINDS CONTINUE FOR THE NEARSHORE WATERS THROUGH EARLY SATURDAY...BEFORE BACKING NORTHEASTERLY AND INCREASING DURING THE DAY WITH THE STRONG PRESSURE GRADIENT BETWEEN ADVANCING CENTRAL PLAINS LOW PRESSURE SYSTEM AND SOUTHERN CANADIAN RIDGING. ONSHORE FLOW WILL BUILD WAVE HEIGHTS INTO THE 3 TO 6 FOOT RANGE FOR THE NEARSHORE WATERS...AND WIND GUSTS INCREASE TO 20 KNOTS OR GREATER FROM ROUGHLY 12Z TO 23Z SATURDAY. STILL APPEARS THAT A SMALL CRAFT ADVISORY WILL BE NEEDED FOR SATURDAY AND SATURDAY NIGHT. SPM && .PREV DISCUSSION... /ISSUED 415 AM CDT FRI APR 24 2015/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH. A VORT MAX OVER NE AND THE ASSOCIATED PVA...THETAE ADVECTION...AND FRONTOGENESIS WILL MOVE INTO SRN WI THIS AFTERNOON. PWS WILL INCREASE TO 0.60-0.80 INCHES BY LATE AFTERNOON AND MESO MODELS ARE SHOWING ORGANIZED AREAS OF RAIN. THE WRF MODELS ARE CONCENTRATING IN THE SRN CWA WHILE THE HRRR IS BRINGING THE RAIN INTO THE NW CWA. THE DIFFERENCES ARE POSSIBLY RELATED TO WHERE THE 850-700 MB FRONTOGENESIS WILL SET UP. A CONSENSUS OF MODEL POPS DOES FOCUS MORE IN THE SOUTH SO WENT WITH 50 POPS BY LATE AFTERNOON THERE WITH SLIGHT CHANCES IN THE FAR NE CWA. THE TEMPS SHOULD BE ABLE TO WARM WELL INTO THE 50S AWAY FROM THE LAKE BEFORE THE THICKER CLOUD COVER ARRIVES BY EARLY AFTERNOON. KEPT THE POPS SIMILAR THROUGH THE EVENING INTO THE EARLY OVERNIGHT PERIOD BEFORE BRINGING LIKELY AND CATEGORICAL POPS TO THE SW CWA. THIS OCCURS AS A STRONGER SHORTWAVE TROUGH CURRENTLY OVER THE DESERT SW MOVES TO THE MID MO RIVER VALLEY BY 12Z SAT. PVA AND 850 MB FRONTOGENESIS INCREASES OVER ERN IA AND NRN IL LATE TNT THEN MOVES INTO FAR SRN WI. EXPECT ALL RAIN WITH SFC TEMPS COOLING INTO THE MID 30S OVER CENTRAL WI TO UPPER 30S FARTHER SOUTH. SATURDAY... FORECAST CONFIDENCE HIGH. THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW WILL WEAKEN AS THEY TRACK FROM THE IA/MO BORDER TO SOUTHERN IL ON SATURDAY. IT WILL BE A RAW DAY IN SOUTHERN WI WITH A DRIVING RAIN FROM THE EAST... ESPECIALLY IN THE MORNING. SOUTHERN WI WILL BE IN THE REGION OF VORTICITY ADVECTION... UPPER DIVERGENCE AND Q-VECTOR CONVERGENCE DUE TO THE RIGHT ENTRANCE REGION OF AN UPPER JET... AND 700MB FRONTOGENESIS AND STRONG UPWARD MOTION. IT LOOKS LIKE THERE WILL BE A TIGHT GRADIENT IN THE QPF AMOUNTS. HIGHEST AMOUNTS SHOULD BE CONCENTRATED WITHIN THE SOUTHERN ONE OR TWO TIERS OF COUNTIES IN SOUTHERN WI AND THEN SOUTH OF THE WI/IL BORDER CLOSEST TO THE LOW. THE GFS IS FARTHEST NORTH WITH THE HIGHER QPF THAN THE CANADIAN...ECMWF AND 06Z NAM. THE THERMAL TROUGH WILL MOVE ACROSS WI DURING THE DAY SATURDAY. THE THERMAL PROFILE LOOKS LIKE RAIN FOR THE WHOLE MKX AREA... BUT IT WILL BE CLOSE WITH A DEEP ISOTHERMAL LAYER RIGHT AROUND ZERO. PRECIP WILL TAPER OFF DURING THE AFTERNOON AND EXPECT DRY WEATHER WITH A BRISK NNE WIND SATURDAY NIGHT. DRY AIR SPREADING INTO THE REGION QUICKLY SHOULD ALLOW FOR CLEARING SKIES EARLY SUNDAY MORNING. EXPECT LOWS TO BE RIGHT AROUND FREEZING. LONG TERM... SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH. RIDGING WILL TAKE HOLD OF THE UPPER MIDWEST EARLY NEXT WEEK. DRY WEATHER UNTIL AT LEAST TUESDAY AFTERNOON. TEMPERATURES WILL BE ON THE RISE FOR INLAND AREAS... BUT A PERSISTENT EASTERLY BREEZE OFF OF LAKE MICHIGAN WILL KEEP LAKESHORE TEMPERATURES IN THE 50S. TUESDAY NIGHT THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM. A 500MB TROUGH WILL CROSS WI TUESDAY EVENING WHICH COULD BRING SOME LIGHT RAIN OR SPRINKLES. THE GFS IS INITIALLY MORE PROGRESSIVE WITH THIS TROUGH THAN THE ECMWF... BUT THEN STALLS THE TROUGH OVER THE NORTHEAST STATES LONGER THAN THE ECMWF LATER NEXT WEEK. OVERALL SOUTHERN WI SHOULD BE DRY... BUT THERE IS PLENTY OF UNCERTAINTY IN TEMPERATURES. AVIATION/12Z TAFS/...MIDDLE LEVEL CLOUDS WILL INCREASE ACROSS SRN WI THIS AFTERNOON AND EVENING ALONG WITH SCT SHOWERS AS A SHORTWAVE TROUGH MOVES INTO THE AREA. THE LOW LEVELS WILL REMAIN FAIRLY DRY SO VFR CONDITIONS WILL STILL PREVAIL WITH PERHAPS MVFR VSBYS WITH ANY HEAVIER SHOWERS THAT MAY OCCUR. THE RAIN WILL BECOME MORE WIDESPREAD FOR SAT AM AS A STRONGER SHORTWAVE TROUGH AND LOW PRESSURE AREA MOVES FROM THE CENTRAL GREAT PLAINS TO THE OHIO RIVER VALLEY. SAT AM IS WHEN THE CIGS WILL DROP TO 1-3.0 KFT AND VSBYS TO 3-5SM WITH THE WIDESPREAD MDT RAINFALL. MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR SAT AND SAT NT. BRISK ELY WINDS WILL DEVELOP ON SAT AS THE PRESSURE GRADIENT TIGHTENS BETWEEN POLAR HIGH PRESSURE OVER SRN CANADA AND LOW PRESSURE MOVING FROM THE CENTRAL GREAT PLAINS INTO THE MIDDLE MS RIVER VALLEY. THE WINDS WILL TURN NELY FOR SAT AFT AND NIGHT AS THE LOW TRACKS ACROSS THE OHIO RIVER VALLEY. WAVE HEIGHTS WILL BUILD TO 3 TO 5 FEET DURING THIS TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...WOOD/SPM TODAY/TONIGHT AND AVIATION/MARINE...GEHRING SATURDAY THROUGH THURSDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
415 AM CDT FRI APR 24 2015 .SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH. A VORT MAX OVER NE AND THE ASSOCIATED PVA...THETAE ADVECTION...AND FRONTOGENESIS WILL MOVE INTO SRN WI THIS AFTERNOON. PWS WILL INCREASE TO 0.60-0.80 INCHES BY LATE AFTERNOON AND MESO MODELS ARE SHOWING ORGANIZED AREAS OF RAIN. THE WRF MODELS ARE CONCENTRATING IN THE SRN CWA WHILE THE HRRR IS BRINGING THE RAIN INTO THE NW CWA. THE DIFFERENCES ARE POSSIBLY RELATED TO WHERE THE 850-700 MB FRONTOGENESIS WILL SET UP. A CONSENSUS OF MODEL POPS DOES FOCUS MORE IN THE SOUTH SO WENT WITH 50 POPS BY LATE AFTERNOON THERE WITH SLIGHT CHANCES IN THE FAR NE CWA. THE TEMPS SHOULD BE ABLE TO WARM WELL INTO THE 50S AWAY FROM THE LAKE BEFORE THE THICKER CLOUD COVER ARRIVES BY EARLY AFTERNOON. KEPT THE POPS SIMILAR THROUGH THE EVENING INTO THE EARLY OVERNIGHT PERIOD BEFORE BRINGING LIKELY AND CATEGORICAL POPS TO THE SW CWA. THIS OCCURS AS A STRONGER SHORTWAVE TROUGH CURRENTLY OVER THE DESERT SW MOVES TO THE MID MO RIVER VALLEY BY 12Z SAT. PVA AND 850 MB FRONTOGENESIS INCREASES OVER ERN IA AND NRN IL LATE TNT THEN MOVES INTO FAR SRN WI. EXPECT ALL RAIN WITH SFC TEMPS COOLING INTO THE MID 30S OVER CENTRAL WI TO UPPER 30S FARTHER SOUTH. SATURDAY... FORECAST CONFIDENCE HIGH. THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW WILL WEAKEN AS THEY TRACK FROM THE IA/MO BORDER TO SOUTHERN IL ON SATURDAY. IT WILL BE A RAW DAY IN SOUTHERN WI WITH A DRIVING RAIN FROM THE EAST... ESPECIALLY IN THE MORNING. SOUTHERN WI WILL BE IN THE REGION OF VORTICITY ADVECTION... UPPER DIVERGENCE AND Q-VECTOR CONVERGENCE DUE TO THE RIGHT ENTRANCE REGION OF AN UPPER JET... AND 700MB FRONTOGENESIS AND STRONG UPWARD MOTION. IT LOOKS LIKE THERE WILL BE A TIGHT GRADIENT IN THE QPF AMOUNTS. HIGHEST AMOUNTS SHOULD BE CONCENTRATED WITHIN THE SOUTHERN ONE OR TWO TIERS OF COUNTIES IN SOUTHERN WI AND THEN SOUTH OF THE WI/IL BORDER CLOSEST TO THE LOW. THE GFS IS FARTHEST NORTH WITH THE HIGHER QPF THAN THE CANADIAN...ECMWF AND 06Z NAM. THE THERMAL TROUGH WILL MOVE ACROSS WI DURING THE DAY SATURDAY. THE THERMAL PROFILE LOOKS LIKE RAIN FOR THE WHOLE MKX AREA... BUT IT WILL BE CLOSE WITH A DEEP ISOTHERMAL LAYER RIGHT AROUND ZERO. PRECIP WILL TAPER OFF DURING THE AFTERNOON AND EXPECT DRY WEATHER WITH A BRISK NNE WIND SATURDAY NIGHT. DRY AIR SPREADING INTO THE REGION QUICKLY SHOULD ALLOW FOR CLEARING SKIES EARLY SUNDAY MORNING. EXPECT LOWS TO BE RIGHT AROUND FREEZING. .LONG TERM... SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH. RIDGING WILL TAKE HOLD OF THE UPPER MIDWEST EARLY NEXT WEEK. DRY WEATHER UNTIL AT LEAST TUESDAY AFTERNOON. TEMPERATURES WILL BE ON THE RISE FOR INLAND AREAS... BUT A PERSISTENT EASTERLY BREEZE OFF OF LAKE MICHIGAN WILL KEEP LAKESHORE TEMPERATURES IN THE 50S. TUESDAY NIGHT THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM. A 500MB TROUGH WILL CROSS WI TUESDAY EVENING WHICH COULD BRING SOME LIGHT RAIN OR SPRINKLES. THE GFS IS INITIALLY MORE PROGRESSIVE WITH THIS TROUGH THAN THE ECWMF... BUT THEN STALLS THE TROUGH OVER THE NORTHEAST STATES LONGER THAN THE ECMWF LATER NEXT WEEK. OVERALL SOUTHERN WI SHOULD BE DRY... BUT THERE IS PLENTY OF UNCERTAINTY IN TEMPERATURES. && .AVIATION/12Z TAFS/...MIDDLE LEVEL CLOUDS WILL INCREASE ACROSS SRN WI THIS AFTERNOON AND EVENING ALONG WITH SCT SHOWERS AS A SHORTWAVE TROUGH MOVES INTO THE AREA. THE LOW LEVELS WILL REMAIN FAIRLY DRY SO VFR CONDITIONS WILL STILL PREVAIL WITH PERHAPS MVFR VSBYS WITH ANY HEAVIER SHOWERS THAT MAY OCCUR. THE RAIN WILL BECOME MORE WIDESPREAD FOR SAT AM AS A STRONGER SHORTWAVE TROUGH AND LOW PRESSURE AREA MOVES FROM THE CENTRAL GREAT PLAINS TO THE OHIO RIVER VALLEY. SAT AM IS WHEN THE CIGS WILL DROP TO 1-3.0 KFT AND VSBYS TO 3-5SM WITH THE WIDESPREAD MDT RAINFALL. && .MARINE...A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR SAT AND SAT NT. BRISK ELY WINDS WILL DEVELOP ON SAT AS THE PRESSURE GRADIENT TIGHTENS BETWEEN POLAR HIGH PRESSURE OVER SRN CANADA AND LOW PRESSURE MOVING FROM THE CENTRAL GREAT PLAINS INTO THE MIDDLE MS RIVER VALLEY. THE WINDS WILL TURN NELY FOR SAT AFT AND NIGHT AS THE LOW TRACKS ACROSS THE OHIO RIVER VALLEY. WAVE HEIGHTS WILL BUILD TO 3 TO 5 FEET DURING THIS TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...GEHRING SATURDAY THROUGH THURSDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
333 AM CDT FRI APR 24 2015 .SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE HIGH. A VORT MAX OVER NE AND THE ASSOCIATED PVA...THETAE ADVECTION...AND FRONTOGENESIS WILL MOVE INTO SRN WI THIS AFTERNOON. PWS WILL INCREASE TO 0.60-0.80 INCHES BY LATE AFTERNOON AND MESO MODELS ARE SHOWING ORGANIZED AREAS OF RAIN. THE WRF MODELS ARE CONCENTRATING IN THE SRN CWA WHILE THE HRRR IS BRINGING THE RAIN INTO THE NW CWA. THE DIFFERENCES ARE POSSIBLY RELATED TO WHERE THE 850-700 MB FRONTOGENESIS WILL SET UP. A CONSENSUS OF MODEL POPS DOES FOCUS MORE IN THE SOUTH SO WENT WITH 50 POPS BY LATE AFTERNOON THERE WITH SLIGHT CHANCES IN THE FAR NE CWA. THE TEMPS SHOULD BE ABLE TO WARM WELL INTO THE 50S AWAY FROM THE LAKE BEFORE THE THICKER CLOUD COVER ARRIVES BY EARLY AFTERNOON. KEPT THE POPS SIMILAR THROUGH THE EVENING INTO THE EARLY OVERNIGHT PERIOD BEFORE BRINGING LIKELY AND CATEGORICAL POPS TO THE SW CWA. THIS OCCURS AS A STONGER SHORTWAVE TROUGH CURRENTLY OVER THE DESERT SW MOVES TO THE MID MO RIVER VALLEY BY 12Z SAT. PVA AND 850 MB FRONTOGENESIS INCREASES OVER ERN IA AND NRN IL LATE TNT THEN MOVES INTO FAR SRN WI. EXPECT ALL RAIN WITH SFC TEMPS COOLING INTO THE MID 30S OVER CENTRAL WI TO UPPER 30S FARTHER SOUTH. SATURDAY... FORECAST CONFIDENCE HIGH. THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW WILL WEAKEN AS THEY TRACK FROM THE IA/MO BORDER TO SOUTHERN IL ON SATURDAY. IT WILL BE A RAW DAY IN SOUTHERN WI WITH A DRIVING RAIN FROM THE EAST... ESPECIALLY IN THE MORNING. SOUTHERN WI WILL BE IN THE REGION OF VORTICITY ADVECTION... UPPER DIVERGENCE AND Q-VECTOR CONVERGENCE DUE TO THE RIGHT ENTRANCE REGION OF AN UPPER JET... AND 700MB FRONTOGENESIS AND STRONG UPWARD MOTION. IT LOOKS LIKE THERE WILL BE A TIGHT GRADIENT IN THE QPF AMOUNTS. HIGHEST AMOUNTS SHOULD BE CONCENTRATED WITHIN THE SOUTHERN ONE OR TWO TIERS OF COUNTIES IN SOUTHERN WI AND THEN SOUTH OF THE WI/IL BORDER CLOSEST TO THE LOW. THE GFS IS FARTHEST NORTH WITH THE HIGHER QPF THAN THE CANADIAN...ECMWF AND 06Z NAM. THE THERMAL TROUGH WILL MOVE ACROSS WI DURING THE DAY SATURDAY. THE THERMAL PROFILE LOOKS LIKE RAIN FOR THE WHOLE MKX AREA... BUT IT WILL BE CLOSE WITH A DEEP ISOTHERMAL LAYER RIGHT AROUND ZERO. PRECIP WILL TAPER OFF DURING THE AFTERNOON AND EXPECT DRY WEATHER WITH A BRISK NNE WIND SATURDAY NIGHT. DRY AIR SPREADING INTO THE REGION QUICKLY SHOULD ALLOW FOR CLEARING SKIES EARLY SUNDAY MORNING. EXPECT LOWS TO BE RIGHT AROUND FREEZING. .LONG TERM... SUNDAY THROUGH TUESDAY... FORECAST CONFIDENCE HIGH. RIDGING WILL TAKE HOLD OF THE UPPER MIDWEST EARLY NEXT WEEK. DRY WEATHER UNTIL AT LEAST TUESDAY AFTERNOON. TEMPERATURES WILL BE ON THE RISE FOR INLAND AREAS... BUT A PERSISTENT EASTERLY BREEZE OFF OF LAKE MICHIGAN WILL KEEP LAKESHORE TEMPERATURES IN THE 50S. TUESDAY NIGHT THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM. A 500MB TROUGH WILL CROSS WI TUESDAY EVENING WHICH COULD BRING SOME LIGHT RAIN OR SPRINKLES. THE GFS IS INITIALLY MORE PROGRESSIVE WITH THIS TROUGH THAN THE ECWMF... BUT THEN STALLS THE TROUGH OVER THE NORTHEAST STATES LONGER THAN THE ECMWF LATER NEXT WEEK. OVERALL SOUTHERN WI SHOULD BE DRY... BUT THERE IS PLENTY OF UNCERTAINTY IN TEMPERATURES. && .AVIATION/12Z TAFS/...COMING SOON. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...GEHRING SATURDAY THROUGH THURSDAY...MRC
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
153 AM EDT SUN APR 26 2015 .SYNOPSIS... DRIER WEATHER RETURNS FOR SUNDAY AS A COLD FRONT MOVES SOUTH ACROSS THE REGION. THE NEXT CHANCE FOR SIGNIFICANT RAIN MOVES IN FOR THE MIDDLE OF NEXT WEEK AS MOISTURE INCREASES AHEAD OF A LOW PRESSURE SYSTEM COMING OUT OF THE GULF OF MEXICO. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A FRONTAL BOUNDARY IS POSITIONED JUST SOUTH OF THE NC/SC BORDER TONIGHT. OBSERVATIONS SHOW NORTHEASTERLY WINDS NORTH OF THE BOUNDARY AND SOUTHWESTERLY WINDS FOR A MAJORITY OF THE FORECAST AREA WHICH IS SOUTH OF THE BOUNDARY. EXPECT ISOLATED SHOWERS AND STORMS TO CONTINUE BEHIND THE QLCS DEPARTING OFF THE COAST. THE HIGHEST MOISTURE IS CURRENTLY ALONG THE SOUTHERN AND EASTERN COUNTIES. MESOANALYSIS ALSO SHOWS WEAK TO MODERATE INSTABILITY REMAINS ACROSS THE SOUTHERN HALF OF THE FORECAST AREA WITH LIFTED INDICES AS LOW AS -4/-5 IN THE SOUTHERNMOST PART OF THE FA. EXPECT THIS AREA TO SEE A MAJORITY OF THE SHOWER ACTIVITY OVER THE NEXT HOUR OR TWO. THE HRRR SEEMS TO BE HANDLING THE ACTIVITY FAIRLY WELL AND SHOWS MOST OF THE ACTIVITY DEPARTING THE FORECAST AREA BY 06Z SO HAVE TRENDED POPS DOWN OVERNIGHT. OBSERVATIONS SHOW LOW VISIBILITIES IN LANCASTER AND CHESTERFIELD COUNTIES CLOSE TO THE FRONTAL BOUNDARY ALTHOUGH LOW LEVEL JET SHOULD LIMIT FOG POTENTIAL SOME OVERNIGHT. OVERNIGHT LOWS REMAIN MILD...ONLY FALLING INTO THE LOWER TO MIDDLE 60S. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/... SOME LINGERING SHOWERS/STORMS POSSIBLE INTO SUNDAY WITH THE NORTHERN MIDLANDS LIKELY TO BE MORE FAVORED SUNDAY AS THE SURFACE LOW SINKS SOUTHEASTWARD ACROSS VA/NC AND OFFSHORE BY SUNDAY EVENING. MODERATE TO STRONG INSTABILITY AND COLD 500 MB TEMPS NOTED ON SUNDAY BUT MOISTURE MAY BE LACKING TO SUPPORT MUCH CONVECTION SO WILL CONTINUE WITH LOW CHANCE POPS ACROSS THE NORTHERN MIDLANDS. SUNDAY LOOKS TO BE A WARM DAY WITH SOME SUNSHINE AND DOWNSLOPING NORTHWESTERLY FLOW WITH HIGHS BACK INTO THE 80S. THE EXCEPTION WILL BE THE EXTREME NORTHERN MIDLANDS WHERE COOLER BEHIND THE AREA OF LOW PRESSURE SHOULD HOLD TEMPERATURES IN THE 70S. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... MEDIUM-RANGE MODELS IN FAIRLY GOOD AGREEMENT WITH THE OVERALL PATTERN NEXT WEEK. ON MON/TUE THE FORECAST AREA WILL BE BETWEEN THE DEPARTING SYSTEM OFF THE EAST COAST AND YET ANOTHER SLOW MOVING CLOSED UPPER LOW EJECTING EASTWARD OUT OF THE SOUTHWESTERN STATES. EXPECT DRY WEATHER AND BELOW NORMAL TEMPERATURES WITH A PERSISTENT NORTHERLY FLOW AND SURFACE HIGH PRESSURE RIDGING INTO THE AREA FROM THE NORTH. THE SOUTHERN STREAM CLOSED LOW WILL BEGIN TO OPEN AND DRIFT EASTWARD EVENTUALLY PHASING WITH NORTHERN STREAM ENERGY BRINGING UNSETTLED WEATHER TO OUR AREA TUESDAY INTO THURSDAY. HOWEVER...THERE ARE SOME DIFFERENCES BETWEEN THE LATEST GFS RUN AND THE PREVIOUS ECMWF FOR THE LATTER PART OF THE PERIOD. THE PREVIOUS ECMWF SHOWS SOME LINGERING PRECIPITATION OVER THE AREA FRIDAY WITH HIGH PRESSURE OVER THE AREA SATURDAY. THE LATEST GFS SHOWS DRY HIGH PRESSURE BUILDING IN FROM THE WEST FRIDAY INTO SATURDAY...BUT ALSO SHOWS ANOTHER CUT-OFF UPPER LOW FORMING OVER THE EASTERN GULF COAST. THIS FEATURE COULD SPREAD PRECIPITATION BACK INTO SC BY LATE SATURDAY. DUE TO UNCERTAINTY...WILL KEEP FRIDAY AND SATURDAY DRY AT THIS TIME. TEMPERATURES GENERALLY AT OR JUST BELOW NORMAL THROUGH THE EXTENDED PERIOD. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... EVENING CONVECTION HAS SHIFTED EAST OF THE AREA AND DRIER AIR ALOFT IS MOVING IN. SURFACE LOW PRESSURE IS MOVING EASTWARD ACROSS THE NC/VA MOUNTAINS AND WILL CONTINUE TO SHIFT EAST ACROSS NC THROUGH THE DAY. CURRENT SATELLITE IMAGERY SHOWS WIDESPREAD LIFR STRATUS/FOG ON THE NORTHSIDE OF A NEARLY STATIONARY FRONT ACROSS THE NORTHERN MIDLANDS. THIS FRONT AND RESTRICTIONS ARE EXPECTED TO REMAIN NORTH OF THE TERMINALS OVERNIGHT BUT THERE HAVE BEEN SIGNS OF POCKETS OF LOW CLOUDS DEVELOPING DUE TO NOCTURNAL COOLING AND MOS GUIDANCE IS SUGGESTING A PERIOD OF MVFR/IFR CIGS IMPACTING THE TERMINALS. CONFIDENCE IS LOW IN THE IFR CIGS DEVELOPING BUT WILL CARRY A PERIOD OF MVFR CIGS 08Z-12Z. STRONG LOW LEVEL JET AROUND 35 KNOTS SHOULD PREVENT/LIMIT FOG DEVELOPMENT ALTHOUGH IT CANNOT BE RULED OUT. INCREASING PRESSURE GRADIENT AND STRONG LOW LEVEL WIND FIELD WILL ALLOW STRONG MIXING TO OCCUR DURING THE DAY TODAY AND EXPECT BREEZY WESTERLY WINDS AROUND 15 KNOTS WITH GUSTS AROUND 25 KNOTS. STRONG INSTABILITY THIS AFTERNOON BUT LIMITED MOISTURE PRECLUDES ANY MENTION OF TSRA IN THIS FORECAST THOUGH THERE IS REASON TO BELIEVE ISOLATED TO SCATTERED STORMS MAY DEVELOP WITH DIURNAL HEATING. EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED MONDAY AND TUESDAY. AN APPROACHING WARM FRONT MAY RESULT IN WIDESPREAD RESTRICTIONS WEDNESDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS POCATELLO ID
326 AM MDT SUN APR 26 2015 .SHORT TERM...TODAY THROUGH TUESDAY AFTERNOON. IT SEEMS THE BEST WAY TO DESCRIBE TODAY`S WEATHER IS MESSY. THE SYSTEM CONTINUES TO SPLIT AS IT IS MOVING EAST. DRIER AIR IS ALREADY WORKING INTO THE WESTERN FRINGE OF OUR FORECAST AREA. MEANWHILE...A PRETTY PERSISTENT BAND OF RAIN AND SNOW EXTENDS FROM AROUND CHALLIS TO POCATELLO TO NEAR MALAD. AT THE SAME TIME...RAIN AND SNOW IS INCREASING TO THE EAST OF THE BAND. SNOW IS FALLING DOWN TO 6000-6500FT. WE WILL LIKELY SEE SOME OF THE HIGHER PASSES...LIKE WE`VE ALREADY SEEN AT WILLOW CREEK SUMMIT...GETTING SNOW AT TIMES. HOWEVER...THE IMPACTS FOR MOST OF THEM WILL BE MINIMAL EXCEPT FOR WILLOW CREEK AND HEADING OVER TETON PASS. THOSE TWO PASSES WILL EVENTUALLY SEE IMPROVING CONDITIONS LATER THIS MORNING. AS THE DAY WEARS ON...WE WILL SEE A GRADUAL SHIFT TO THE EASTERN HIGHLANDS WITH THE FOCUS FOR PRECIPITATION. SNOW LEVELS WILL BOUNCE BACK TO 6500-7500FT BY AFTERNOON. IT DOES APPEAR THAT WE WILL SEE SOME INSTABILITY SHOWERS ACROSS PORTIONS OF THE CENTRAL MOUNTAINS AND SNAKE PLAIN. THE GFS AND THE HRRR ARE ACTUALLY TRYING TO DEPICT THE POTENTIAL FOR A CONVERGENCE BAND...POSSIBLY AS FAR SOUTH AS CRATERS TO AROUND FORT HALL. THAT IS SOMETHING THAT WILL NEED TO BE MONITORED CLOSELY. BREEZY CONDITIONS WILL DEVELOP IN TWO SEPARATE LOCATIONS TODAY. THE FIRST WILL BE ACROSS THE UPPER PLAIN AND HIGHLANDS AS NORTHERLY WINDS KICK IN. THE MAGIC VALLEY AND SOUTH-CENTRAL HIGHLANDS IS THE OTHER...AND WILL LIKELY SEE THE STRONGEST WINDS. SUSTAINED WINDS OF 20-30 MPH ARE FORECAST WITH 30-35 MPH IN ISOLATED SPOTS. THIS IS TOO LOW FOR A WIND ADVISORY...BUT IF ENOUGH PLOWING IS ONGOING THERE COULD BE SOME BLOWING DUST IN AREAS THAT SAW LITTLE TO NO RAINFALL. MONDAY AND TUESDAY WILL BE DRIER AND MUCH WARMER WITH HIGH PRESSURE BUILDING ACROSS THE WEST. BY TUESDAY...HIGHS WILL BE WELL INTO THE 70S FOR THE VALLEYS AND 50S/60S IN THE MOUNTAINS. KEYES .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY NIGHT. BOTH GFS AND ECMWF IN AGREEMENT WITH THE UPPER RIDGE MOVING OFF TO THE EAST AND A STRONG UPPER TROF MOVING INTO THE PAC NW BY WED MORN. THE TROF THEN PASSES THRU ID ON THU. MOISTURE APPEARS TO BE LIMITED WITH THIS SYSTEM. THIS WILL RESULT IN A FEW SHOWERS IN THE CENTRAL MTNS WED AFTN AS THE INCREASING SW FLOW INTERACTS WITH THE TERRAIN. PRECIP INCREASES IN COVERAGE ACROSS THE CENTRAL MTNS AND INTO THE UPPER SNAKE HIGHLANDS WED NIGHT AS THE UPPER TROF APPROACHES. BY THU...A COLD FRONT PASSES THRU PUSHING MOST OF THE PRECIP OUT OF THE AREA EXCEPT FOR LINGERING SHOWERS IN THE EASTERN HIGHLANDS. STRONG WEST TO SW WINDS ALONG WITH COOLER TEMPS ON THU. THE ECMWF IS A LITTLE SLOWER WITH THIS SYSTEM...SO PRECIP IS A LITTLE MORE WIDESPREAD THAN THE MOSTLY DRY GFS. NOW THE PICTURE GETS MUDDY. THE GFS DEVELOPS A BROAD RIDGE OVER THE PAC NW ON FRI...WHILE THE ECMWF DOES JUST THE OPPOSITE WITH A BROAD TROF. THE GFS MAINTAINS A DRY FCST THRU SUN WITH A DOMINANT RIDGE...WHILE THE ECMWF DEVELOPS A CLOSED LOW OVER WA. THE ECMWF SUGGESTS A WET SUN AND SUNDAY NIGHT...WHILE THE GFS IS DRY. WILL CARRY LOW CHC FOR SHOWERS OVER THE EASTERN HIGHLANDS SUN AND SUN NIGHT AND LEAVE THE REST OF THE FCST AREA DRY UNTIL THE PICTURE BECOMES CLEARER. HEDGES && .AVIATION...SHOWERS WILL MOVE OUT OF THE AREA LATER THIS MORN...WITH IMPROVING CIGS BY AFTN. SW WINDS WILL BR RATHER STRONG TODAY ACROSS THE SNAKE RIVER PLAIN. WINDS WILL SETTLE DOWN BY EVE. HEDGES && .PIH WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
344 AM CDT SUN APR 26 2015 ...UPDATED LONG TERM SECTION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 230 AM CDT SUN APR 26 2015 THE DEPTH OF THE LOW LEVEL MOISTURE WILL BE THE KEY TO CHANCES OF LIGHT PRECIPITATION ACROSS SOUTHWEST KANSAS TODAY. AT THIS TIME THE DEPTH OF THIS MOIST LAYER WILL BE JUST BELOW 3000FT AGL BASED ON THE NAM AND GFS MODEL SOUNDINGS. THE DEPTH OF THIS MOIST LAYER WILL BE SLIGHTLY DEEPER WEST OF HIGHWAY 283 THAN EAST SO GIVEN THIS WILL FAVOR KEEPING A MENTION OF DRIZZLE GOING NEAR AND WEST OF DODGE CITY TODAY. IN ADDITION 700MB TO 500MB LAPSE RATES ARE FORECAST TO BE GREATER THAN 8C/KM AS A WEAK 400MB POTENTIAL VORTICITY ANOMALY CROSSES SOUTHWEST KANSAS EARLY IN THE DAY. THIS MAY BRIEFLY ENHANCE LIFT ENOUGH FOR A PERIOD OF LIGHT RAINSHOWERS DURING THE FIRST HALF OF THE DAY. TEMPERATURES ARE NOT EXPECTED TO WARM MUCH THROUGH THE AFTERNOON GIVEN THE EXPECTED CLOUD COVER SO HAVE KEPT THE DIURNAL TEMPERATURE TREND TO AROUND 10 DEGREES OR LESS. THE EXCEPTION WILL BE ACROSS SOUTH CENTRAL KANSAS. AFTER 00Z MONDAY ANOTHER, STRONGER, UPPER LEVEL WAVE WILL MOVE NORTH ACROSS THE TEXAS PANHANDLE AND APPROACH SOUTHWEST KANSAS. GIVEN SOME MID LEVEL INSTABILITY AND IMPROVING LIFT AHEAD OF THIS NEXT UPPER WAVE EARLY TONIGHT THERE WILL BE ANOTHER CHANCE FOR CONVECTION TO OCCUR, MAINLY IN SOUTHERN KANSAS NEAR THE OKLAHOMA BORDER. CURRENTLY AM CONCERNED ABOUT HOW FAR NORTH THE PRECIPITATION CHANCES WILL BE GIVEN THE LOCATION OF THE 700MB TO 500MB DEFORMATION ZONE AND THE SLIGHTLY TRACK OF THE UPPER LOW ACROSS WEST TEXAS. GIVEN THIS TREND ALONG WITH WHERE THE BETTER MOISTURE, INSTABILITY AND LIFT WILL BE OVERNIGHT WILL BEGIN TO LOWER PRECIPITATION CHANCES ACROSS NORTH CENTRAL KANSAS. FURTHER SOUTH THE HIGHEST FOR OVERNIGHT PRECIPITATION WILL BE NEAR THE OKLAHOMA BORDER. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 343 AM CDT SUN APR 26 2015 THE NAM AND THE ECMWF ARE THE SOLUTIONS WITH THE SHARPEST CUTOFF OF PLACEMENT OF THE NORTHERN PERIPHERY OF COLD CONVEYOR BELT PRECIPITATION/CLOUDS ACROSS THE FAR SOUTHERN KANSAS COUNTIES FOR MONDAY. BY COMPARISON, THE GFS IS THE FARTHER NORTH SOLUTION. HOWEVER IN EITHER CASE, THE MODELS ARE BEGINNING TO SUGGEST A WEDGE OF DRY MID LEVEL AIR JUST TO THE NORTH OF THE DEFORMATION AXIS, SUGGESTING LOWERED CHANCES OF PRECIPITATION IN OUR NORTHERN COUNTIES, FROM AROUND SCOTT CITY TO HAYS. AS SUCH WE`VE USED A MODEL BLEND TOWARD THE CURRENT SOLUTIONS WHICH IS WARMER ACROSS OUR FURTHEST NORTHEAST COUNTIES, AND CONTINUED TO TREND LOWER THE POPS ACROSS THOSE AREAS. CAPE IS BASICALLY NONEXISTENT ACROSS THE SOUTHERN COUNTIES EARLY MONDAY, LEAVING DEFORMATION AND ISENTROPIC UPGLIDE THE MAIN MECHANISMS FOR FORCING, PRODUCING RAIN, AND COOL CONDITIONS ACROSS THE SOUTHERN COUNTIES. BEYOND THE MONDAY TIMEFRAME, THE PATTERN APPEARS FAIRLY BENIGN WITH A MEAN WARMING TREND THROUGH THE WEEKEND. TEMPERATURES MAY WARM TO THE 80S BY THE THURSDAY-SATURDAY TIMEFRAME AS A SOUTHWEST SURFACE FLOW DEVELOPS. THE POLAR WESTERLIES SETUP ACROSS THE NORTHERN PLAINS WITH A STRONG WAVE MODELED BY THE GFS AND ECMWF TO DIVE THROUGH THE CENTRAL GREAT PLAINS AROUND LATE FRIDAY OR SATURDAY. AN ASSOCIATED COLD FRONT COULD BE A FOCUS FOR CONVECTION, WHICH THE GFS IS MORE AGGRESSIVE WITH AT THIS TIME, HOWEVER THE BLEND SOLUTION DERTERMINES THE NEXT BEST CHANCE FOR MEASUREABLE PRECIPITATION TO BE SATURDAY NIGHT OR SUNDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1214 AM CDT SUN APR 26 2015 SATELLITE AND SURFACE OBSERVATIONS EARLY TONIGHT SHOWING LIFR CEILINGS SPREADING SOUTHWEST ACROSS WESTERN KANSAS. BASED ON LOWERING CEILINGS FROM THE UPSTREAM OBSERVATIONS, 00Z NAM BUFR SOUNDINGS, ALONG WITH THE LATEST RAP AND HRRR THE CEILINGS WILL FALL INTO THE LIFR CATEGORY BY 06Z SUNDAY AND THEN REMAIN BELOW 500FT AGL THROUGH AT LEAST 15Z. CEILINGS WILL THEN GRADUALLY IMPROVE INTO THE MVFR CATEGORY BETWEEN 18Z AND 21Z. VISIBILITIES SHOULD STAY IN THE MVFR CATEGORY BASED ON THE MODEL SOUNDINGS AND GIVEN THAT NORTHEAST WINDS WILL BE AT 10 TO 15 KNOTS. && .PRELIMINARY POINT TEMPS/POPS... DDC 56 42 48 40 / 10 60 60 30 GCK 54 43 47 38 / 20 50 60 20 EHA 56 41 46 38 / 30 90 80 30 LBL 58 45 46 40 / 40 80 80 40 HYS 55 41 59 40 / 10 20 30 20 P28 65 48 50 43 / 10 70 70 50 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...RUSSELL AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
237 AM CDT SUN APR 26 2015 ...UPDATED SHORT TERM FORECAST... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 230 AM CDT SUN APR 26 2015 THE DEPTH OF THE LOW LEVEL MOISTURE WILL BE THE KEY TO CHANCES OF LIGHT PRECIPITATION ACROSS SOUTHWEST KANSAS TODAY. AT THIS TIME THE DEPTH OF THIS MOIST LAYER WILL BE JUST BELOW 3000FT AGL BASED ON THE NAM AND GFS MODEL SOUNDINGS. THE DEPTH OF THIS MOIST LAYER WILL BE SLIGHTLY DEEPER WEST OF HIGHWAY 283 THAN EAST SO GIVEN THIS WILL FAVOR KEEPING A MENTION OF DRIZZLE GOING NEAR AND WEST OF DODGE CITY TODAY. IN ADDITION 700MB TO 500MB LAPSE RATES ARE FORECAST TO BE GREATER THAN 8C/KM AS A WEAK 400MB POTENTIAL VORTICITY ANOMALY CROSSES SOUTHWEST KANSAS EARLY IN THE DAY. THIS MAY BRIEFLY ENHANCE LIFT ENOUGH FOR A PERIOD OF LIGHT RAINSHOWERS DURING THE FIRST HALF OF THE DAY. TEMPERATURES ARE NOT EXPECTED TO WARM MUCH THROUGH THE AFTERNOON GIVEN THE EXPECTED CLOUD COVER SO HAVE KEPT THE DIURNAL TEMPERATURE TREND TO AROUND 10 DEGREES OR LESS. THE EXCEPTION WILL BE ACROSS SOUTH CENTRAL KANSAS. AFTER 00Z MONDAY ANOTHER, STRONGER, UPPER LEVEL WAVE WILL MOVE NORTH ACROSS THE TEXAS PANHANDLE AND APPROACH SOUTHWEST KANSAS. GIVEN SOME MID LEVEL INSTABILITY AND IMPROVING LIFT AHEAD OF THIS NEXT UPPER WAVE EARLY TONIGHT THERE WILL BE ANOTHER CHANCE FOR CONVECTION TO OCCUR, MAINLY IN SOUTHERN KANSAS NEAR THE OKLAHOMA BORDER. CURRENTLY AM CONCERNED ABOUT HOW FAR NORTH THE PRECIPITATION CHANCES WILL BE GIVEN THE LOCATION OF THE 700MB TO 500MB DEFORMATION ZONE AND THE SLIGHTLY TRACK OF THE UPPER LOW ACROSS WEST TEXAS. GIVEN THIS TREND ALONG WITH WHERE THE BETTER MOISTURE, INSTABILITY AND LIFT WILL BE OVERNIGHT WILL BEGIN TO LOWER PRECIPITATION CHANCES ACROSS NORTH CENTRAL KANSAS. FURTHER SOUTH THE HIGHEST FOR OVERNIGHT PRECIPITATION WILL BE NEAR THE OKLAHOMA BORDER. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 342 PM CDT SAT APR 25 2015 FOR SUNDAY NIGHT INTO MONDAY, A STRONG UPPER LOW OVER CENTRAL NEW MEXICO WILL MOVE INTO THE SOUTHERN PLAINS ON MONDAY WITH INCREASING CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS. THE PRECIPITATION WILL BE SPREADING FROM FAR SOUTHWESTERN KANSAS INTO MUCH OF SOUTH CENTRAL KANSAS NEAR OR SOUTH OF HAYS. WILL RANGE RAIN CHANCES FROM AROUND 20 PERCENT AT HAYS TO 60 AT DODGE CITY AND AROUND 90 PERCENT AT LIBERAL AND ELKHART. RAINFALL AMOUNTS COULD BE LOCALLY HEAVY, WITH OVER AN INCH SOUTH AND SOUTHWEST OF DODGE CITY. LOWS MONDAY MORNING WILL BE IN THE LOW TO MID 40S. HIGH TEMPS WILL BE COOLEST OVER WESTERN KANSAS WITH HIGHS FROM THE MID AND UPPER 40S THERE, TO THE MID AND UPPER 50S EAST OF DODGE CITY. FOR TUESDAY, THE UPPER LOW OVER OKLAHOMA WILL MOVE SLOWLY EAST. THE NEW ECMWF HAS THE LOW MOVING OUT MUCH FASTER THAN THE GFS AND CANADIAN. WILL CONTINUE WITH LINGERING SHOWERS ENDING FROM NEAR DODGE CITY AND SOUTH. LOWS TUESDAY MORNING WILL BE FROM 39 WEST TO THE MID 40S OVER PARTS OF SOUTH CENTRAL KANSAS. HIGHS WILL WARM INTO THE LOWER TO MID 60S. FOR THE PERIOD WEDNESDAY INTO NEXT SATURDAY, DRY WEATHER IS EXPECTED WITH A TROUGH OVER THE WESTERN UNITED STATES SLOWLY MOVING EAST INTO THE WESTERN HIGH PLAINS INTO THE WEEKEND. LOWS WILL WARM FROM THE 40S TO THE 50S. HIGHS WILL WARM FROM THE LOW 70S ON WEDNESDAY TO AROUND 80 FOR FRIDAY AND SATURDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1214 AM CDT SUN APR 26 2015 SATELLITE AND SURFACE OBSERVATIONS EARLY TONIGHT SHOWING LIFR CEILINGS SPREADING SOUTHWEST ACROSS WESTERN KANSAS. BASED ON LOWERING CEILINGS FROM THE UPSTREAM OBSERVATIONS, 00Z NAM BUFR SOUNDINGS, ALONG WITH THE LATEST RAP AND HRRR THE CEILINGS WILL FALL INTO THE LIFR CATEGORY BY 06Z SUNDAY AND THEN REMAIN BELOW 500FT AGL THROUGH AT LEAST 15Z. CEILINGS WILL THEN GRADUALLY IMPROVE INTO THE MVFR CATEGORY BETWEEN 18Z AND 21Z. VISIBILITIES SHOULD STAY IN THE MVFR CATEGORY BASED ON THE MODEL SOUNDINGS AND GIVEN THAT NORTHEAST WINDS WILL BE AT 10 TO 15 KNOTS. && .PRELIMINARY POINT TEMPS/POPS... DDC 57 42 53 41 / 20 60 60 30 GCK 53 43 49 40 / 30 50 60 20 EHA 54 41 46 39 / 50 90 90 40 LBL 57 45 48 41 / 30 80 90 50 HYS 54 41 58 40 / 20 20 30 20 P28 65 48 56 44 / 10 70 70 50 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...KRUSE AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1217 AM CDT SUN APR 26 2015 ...UPDATED SYNOPSIS AND AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 1214 AM CDT SUN APR 26 2015 AT 00Z SUNDAY A +100KT 250MB JET WAS LOCATED ON THE WEST SIDE OF AN UPPER LEVEL TROUGH WHICH EXTENDED FROM SOUTHERN NEVADA INTO EASTERN WASHINGTON. EAST OF THIS UPPER LEVEL TROUGH A WEAK 500MB RIDGE AXIS WAS LOCATED ACROSS THE CENTRAL AND NORTHERN PLAINS. ALSO EVIDENT OVER THE CENTRAL HIGH PLAINS WAS A SUBTLE UPPER LEVEL WAVE MOVING THROUGH THIS UPPER LEVEL RIDGE AXIS. ONE SURFACE BOUNDARY AT 00Z SUNDAY APPEARS TO EXTEND FROM SOUTHEAST COLORADO INTO WESTERN OKLAHOMA WHILE ANOTHER BOUNDARY APPEARS TO EXTEND FROM SOUTHWEST NEBRASKA INTO SOUTHEAST KANSAS. BEHIND THIS SECOND BOUNDARY COOLER AIR WAS PRESENT AT THE SURFACE AND THE 850MB LEVEL ALONG WITH WIDESPREAD LOW CLOUDS SPREADING SOUTH/SOUTHWEST. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 245 PM CDT SAT APR 25 2015 A STRONG SHORTWAVE TROUGH THAT TRAVERSED THE CENTRAL PLAINS YESTERDAY HAS MOVED EASTWARD INTO THE MIDWEST, SHIFTING THE LOW LEVEL MOIST AXIS EASTWARD AND SOUTHEASTWARD INTO LOUISIANA AND SOUTHEASTERN TEXAS. NORTHWESTERLY SURFACE WINDS HAD RESULT IN DOWNSLOPE WARMING, WITH TEMPERATURES IN THE 70S ACROSS ALL OF SOUTHWESTERN KANSAS. SOME COLD ADVECTION WAS BEGINNING TO DEVELOP ACROSS NORTHERN KANSAS. SOME CONVECTION WAS DEVELOPING THIS AFTERNOON ACROSS WEST CENTRAL KANSAS ALONG A WEAK LOW LEVEL CONVERGENCE ZONE; AND A FEW SHOWERS WITH A RUMBLE OR TWO OF THUNDER ARE POSSIBLE WITH THIS THROUGH THE EVENING. THE NEXT SHORTWAVE TROUGH WAS DIGGING INTO THE SOUTHWESTERN UNITED STATES. AS THIS SYSTEM CONTINUES TO PROGRESS INTO THE SOUTHERN ROCKIES TONIGHT, A COOLER AIRMASS OVER THE UPPER MIDWEST INTO NEBRASKA WILL MOVE SOUTHWESTWARD INTO KANSAS, WITH UPSLOPE EAST TO NORTHEAST WINDS DEVELOPING. THIS COOLER UPSTREAM AIRMASS WAS ALREADY MOIST, WITH TEMPERATURES IN THE UPPER 40S AND DEWPOINTS IN THE MID 40S ACROSS EASTERN NEBRASKA. THEREFORE, AS THIS AIR MOVES UP SLOPE INTO SOUTHWESTERN KANSAS, EXTENSIVE LOW CLOUDINESS WILL RESULT. IN ADDITION, THE MOIST LAYER WILL APPROACH 1 KM IN DEPTH, WHICH WOULD BE FAVORABLE FOR DRIZZLE DEVELOPMENT TOWARD MORNING, ESPECIALLY FROM GARDEN CITY AND SCOTT CITY WESTWARD TO THE COLORADO BORDER. AS THE UPPER LEVEL SYSTEM OVER THE DESERT SOUTHWEST MOVES EVEN CLOSER AND BEGINS TO CLOSE OFF, THE LOW LEVEL MOISTURE THAT HAD BEEN SUPPRESSED WELL TO THE SOUTHEAST WILL BEGIN TO BE DRAWN NORTHWARD AHEAD OF THE UPPER LOW AND OVER THE LOW LEVEL FRONTAL SURFACE. HOWEVER, ANY SIGNIFICANT PRECIPITATION WILL LIKELY HOLD OFF UNTIL JUST AFTER 7 PM SUNDAY, SO THAT THE DETAILS OF THIS WILL BE DISCUSSED IN THE LONG TERM DISCUSSION. LOWS TONIGHT SHOULD FALL TO THE MID TO UPPER 40S BASED ON CURRENT TEMPERATURES IN THE CLOUDY AIRMASS OVER EASTERN NEBRASKA. TEMPERATURES ON SUNDAY SHOULD ONLY RISE A FEW DEGREES DUE TO THE CLOUD COVER, WITH 50S ACROSS MOST OF WESTERN KANSAS, AND SOME 60S IN SOUTH CENTRAL KANSAS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 342 PM CDT SAT APR 25 2015 FOR SUNDAY NIGHT INTO MONDAY, A STRONG UPPER LOW OVER CENTRAL NEW MEXICO WILL MOVE INTO THE SOUTHERN PLAINS ON MONDAY WITH INCREASING CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS. THE PRECIPITATION WILL BE SPREADING FROM FAR SOUTHWESTERN KANSAS INTO MUCH OF SOUTH CENTRAL KANSAS NEAR OR SOUTH OF HAYS. WILL RANGE RAIN CHANCES FROM AROUND 20 PERCENT AT HAYS TO 60 AT DODGE CITY AND AROUND 90 PERCENT AT LIBERAL AND ELKHART. RAINFALL AMOUNTS COULD BE LOCALLY HEAVY, WITH OVER AN INCH SOUTH AND SOUTHWEST OF DODGE CITY. LOWS MONDAY MORNING WILL BE IN THE LOW TO MID 40S. HIGH TEMPS WILL BE COOLEST OVER WESTERN KANSAS WITH HIGHS FROM THE MID AND UPPER 40S THERE, TO THE MID AND UPPER 50S EAST OF DODGE CITY. FOR TUESDAY, THE UPPER LOW OVER OKLAHOMA WILL MOVE SLOWLY EAST. THE NEW ECMWF HAS THE LOW MOVING OUT MUCH FASTER THAN THE GFS AND CANADIAN. WILL CONTINUE WITH LINGERING SHOWERS ENDING FROM NEAR DODGE CITY AND SOUTH. LOWS TUESDAY MORNING WILL BE FROM 39 WEST TO THE MID 40S OVER PARTS OF SOUTH CENTRAL KANSAS. HIGHS WILL WARM INTO THE LOWER TO MID 60S. FOR THE PERIOD WEDNESDAY INTO NEXT SATURDAY, DRY WEATHER IS EXPECTED WITH A TROUGH OVER THE WESTERN UNITED STATES SLOWLY MOVING EAST INTO THE WESTERN HIGH PLAINS INTO THE WEEKEND. LOWS WILL WARM FROM THE 40S TO THE 50S. HIGHS WILL WARM FROM THE LOW 70S ON WEDNESDAY TO AROUND 80 FOR FRIDAY AND SATURDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1214 AM CDT SUN APR 26 2015 SATELLITE AND SURFACE OBSERVATIONS EARLY TONIGHT SHOWING LIFR CEILINGS SPREADING SOUTHWEST ACROSS WESTERN KANSAS. BASED ON LOWERING CEILINGS FROM THE UPSTREAM OBSERVATIONS, 00Z NAM BUFR SOUNDINGS, ALONG WITH THE LATEST RAP AND HRRR THE CEILINGS WILL FALL INTO THE LIFR CATEGORY BY 06Z SUNDAY AND THEN REMAIN BELOW 500FT AGL THROUGH AT LEAST 15Z. CEILINGS WILL THEN GRADUALLY IMPROVE INTO THE MVFR CATEGORY BETWEEN 18Z AND 21Z. VISIBILITIES SHOULD STAY IN THE MVFR CATEGORY BASED ON THE MODEL SOUNDINGS AND GIVEN THAT NORTHEAST WINDS WILL BE AT 10 TO 15 KNOTS. && .PRELIMINARY POINT TEMPS/POPS... DDC 42 53 41 64 / 60 60 30 20 GCK 43 49 40 65 / 60 60 20 10 EHA 41 46 39 61 / 90 90 40 10 LBL 45 48 41 62 / 80 90 50 20 HYS 41 58 40 67 / 30 30 20 10 P28 48 56 44 65 / 60 70 50 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BURGERT SHORT TERM...FINCH LONG TERM...KRUSE AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
507 AM EDT SUN APR 26 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT SUN APR 26 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW MID LEVEL RIDGE EXTENDING FROM THE NRN PLAINS TO SRN HUDSON BAY. TO THE SE...A MID LEVEL LOW IS CENTERED OFF THE CANADIAN MARITIMES WITH ITS BROAD CIRCULATION EXTENDING BACK TO THE UPPER LAKES. TWO SHORTWAVES OF NOTE ARE SWINGING W IN THE MID LEVEL LOW CIRCULATION ACROSS SE CANADA. THE FIRST IS S OF JAMES BAY AND THE SECOND IS N OF MAINE. AT THE SFC... THE MID LEVEL RIDGE IS SUPPORTING HIGH PRES RIDGING S FROM HUDSON BAY INTO THE UPPER MISSISSIPPI VALLEY. UNDER DRY AIR MASS PER 00Z REGIONAL SOUNDINGS...CLEAR SKIES CONTINUE TO PREVAIL ACROSS THE FCST AREA EARLY THIS MORNING. TO THE NE...FIRST SHORTWAVE S OF JAMES IS HELPING TO SPREAD SCT-BKN CLOUDS TOWARD LAKE SUPERIOR. THE FIRST SHORTWAVE S OF JAMES BAY WILL ROTATE INTO NRN LWR MI THIS AFTN/EVENING...SPREADING SOME CLOUDINESS INTO THE ERN FCST AREA TODAY. TRENDS IN THE MODELS SHOW A BACKING OFF ON THE POTENTIAL CLOUD COVER WHICH SEEMS REASONABLE BASED ON OVERNIGHT SATELLITE IMAGERY. FCST THUS REFLECTS A MORE OPTIMISTIC SKY CONDITION FOR CNTRL UPPER MI TODAY. MAY STILL SEE SOME PERIODS OF MOSTLY CLOUDY CONDITIONS OVER THE ERN FCST AREA THIS AFTN...ESPECIALLY LATE. AS FOR TEMPS...RATHER BRISK GRADIENT FLOW OFF LAKE SUPERIOR WILL HOLD TEMPS TO THE LOWER 40S NEAR LAKE SUPERIOR TODAY. MOST LAKESIDE LOCATIONS FROM THE KEWEENAW EASTWARD WILL NOT GET OUT OF THE 30S. WELL INLAND...NAM/GFS FCST SOUNDINGS AND PROJECTED MIXING HEIGHTS SUGGEST HIGH TEMPS MAY STRUGGLE TO REACH 50F. THERE MAY BE SOME LWR 50S TOWARD THE MI/WI BORDER FROM MENOMINEE COUNTY TO IRON COUNTY. TONIGHT...SECOND SHORTWAVE NOW N OF MAINE WILL FOLLOW THE SAME TRACK AS THE FIRST AND SHOULD REACH NRN LWR MI LATE TONIGHT. MODELS ARE AGGRESSIVE IN SWINGING MOISTURE BACK INTO UPPER MI TONIGHT WITH THIS FEATURE. OF PARTICULAR NOTE IS THE LOW-LEVEL MOISTURE THE NAM/GFS SHOW. LOOKING TO THE NE...LOW CIGS ARE NOTED IN AND AROUND JAMES BAY AND EASTWARD EARLY THIS MORNING. WITH THIS MOISTURE PUSHING SW INTO THE AREA DURING THE NIGHT WHEN DAYTIME HEATING IS ABSENT TO HELP LIFT OR MIX MOISTURE OUT...IT LOOKS FAIRLY LIKELY THAT LOW CLOUDS WILL DEVELOP/EXPAND TONIGHT...ESPECIALLY LATE...OVER AT LEAST THE NCNTRL AND E...AIDED BY UPSLOPE FLOW. NAM FCST SOUNDINGS EVEN SUGGEST THE POTENTIAL FOR SOME -DZ/-FZDZ WHERE STRONGEST UPSLOPE OCCURS. WILL BE SOMETHING TO TAKE A LOOK AT AGAIN IN LATER MODEL RUNS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 400 AM EDT SUN APR 26 2015 LINGERING LOW LEVEL MOISTURE AND COOLER AIRMASS BEHIND A SHORTWAVE TROUGH THAT MOVED THROUGH SUN NIGHT WILL LEAD TO CLOUD COVER EARLY MON OVER ESPECIALLY THE CENTRAL AND ERN CWA. THE CLOUD COVER WILL SLOWLY DIMINISH AS THE SFC RIDGE MOVES BACK IN FROM THE W AS WELL AS THE APPROACH OF AN UPPER RIDGE. CAN NOT COMPLETELY RULE OUT SOME LIGHT DRIZZLE IN UPSLOPE AREAS OF NCENTRAL UPPER MI...BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN THE FORECAST. INTERIOR W SHOULD SEE HIGHS APPROACH 60F ON MON...WHILE LAKESHORE AND ERN AREAS ARE QUITE A BIT COOLER WITH HIGHS IN THE UPPER 30S TO THE UPPER 40S. A COUPLE OF ROUNDS OF SHORTWAVE ENERGY WILL BREAK DOWN THE RIDGE TUE EVENING AND AGAIN ON WED...WITH MODELS CURRENTLY SHOWING THE STRONGER SHORTWAVE ON WED. MODELS HAVE NOT SHOWN GOOD CONTINUITY WITH THESE FEATURES...SO CONFIDENCE IN EXACT DETAILS IS LOW. HOWEVER...MODEL DO GENERALLY AGREE THAT MOISTURE WILL BE LIMITED ENOUGH TO KEEP ANY SIGNIFICANT PRECIP FROM OCCURING. TUE WILL BE WARMER THAN MON WITH HIGHS IN THE 50S AND 60S AS THE AIRMASS WILL BE WARMER AND THE SHORTWAVE/CLOUD COVER DOES NOT ARRIVE UNTIL LATER IN THE DAY. WED COULD SEE A SIGNIFICANT COOLER AIRMASS DEPENDING ON DETAILS WITH THE SHORTWAVE...POSSIBLY RESULTING IN HIGH TEMPS IN THE 40S TO MID 50S. UPPER RIDGING REPLACES THE SHORTWAVE ENERGY THU INTO FRI. MODELS HAVE BEEN STRUGGLING WITH CONTINUITY IN THE STRENGTH OF THE RIDGE...LIMITED CONFIDENCE SOME. HIGHS ON THU WILL BE IN THE 50S TO MID 60S...WITH SIGNIFICANTLY WARMER HIGHS IN THE 60S TO LOW 70S ON FRI. MODEL DISAGREEMENT AND DISCONTINUITY CERTAINLY CONTINUE AND INCREASE ON SAT AS MODELS VARY VASTLY IN THE STRENGTH AND PLACEMENT OF UPPER LEVEL ENERGY OVER CENTRAL CANADA. MODELS SHOW SOME SHORTWAVE ENERGY MOVING ACROSS THE CWA WITH A WEAK SFC TROUGH LATE FRI AND FRI NIGHT...WHICH COULD PRODUCE CONVECTION ACROSS THE CWA. WILL CONTINUE SHOWING SLIGHT CHANCE POPS GIVEN UNCERTAINTY. ADDITIONAL DIFFERENCE BETWEEN MODELS /ALSO TIED TO UNCERTAINTIES WITH THE CENTRAL CANADA ENERGY/ WITH TEMPS ON SAT. THE 12Z/25 ECMWF BRINGS AN AMPLIFIED UPPER RIDGE TO JUST W OF THE CWA BY 00Z SUN WHILE THE 00Z/26 GFS HAS AN UPPER TROUGH WHERE THE ECMWF HAS THE RIDGE. AIRMASS WILL BE A LOT WARMER UNDER THE ECMWF SOLUTION WITH 850MB TEMPS OF 12C BY 00Z SUN WHILE THE GFS IS AT 8C. WHILE POTENTIAL FOR MUCH WARMER TEMPS EXISTS...CONFIDENCE IS LOW SO WILL CONTINUE WITH A CONSENSUS APPROACH WITH HIGHS INT HE 60S AND 70S AWAY FROM THE IMMEDIATE LAKESHORE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 138 AM EDT SUN APR 26 2015 A RIDGE OF HIGH PRESSURE OVER CENTRAL LAKE SUPERIOR WILL SLOWLY SHIFT WEST OVER THE MINNESOTA ARROWHEAD TODAY. THIS WILL LEAD TO PERSISTENT NORTHERLY FLOW AT ALL THREE TAF SITES UNDER VFR CONDITIONS. THE MAIN CONCERN IS THE POTENTIAL FOR MVFR CLOUDS TO DEVELOP UNDER THE LOW LEVEL NORTH-NORTHEASTERLY FLOW EARLY THIS MORNING AND INTO THE DAY AT KSAW AND MAYBE KCMX. SINCE THE LOW CLOUDS IN NORTHERN ONTARIO HAVE STRUGGLED TO EXPAND THUS FAR AND MODELS ARE TRENDING DRIER...OPTED TO BACK AWAY FROM THE MVFR CEILINGS AT KSAW FOR EARLY THIS MORNING THROUGH EARLY AFTERNOON. HAVE STILL KEPT SCT CLOUDS FOR THAT PERIOD...BUT CONFIDENCE IS LOW. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 507 AM EDT SUN APR 26 2015 WITH SFC HIGH PRES RIDGING S THRU WRN LAKE SUPERIOR TODAY THRU MON...WINDS WILL BE LIGHTEST OVER WRN LAKE SUPERIOR...MOSTLY UNDER 15KT. OVER THE E...WINDS WILL OCCASIONALLY GUST TO 20-25KT. THE RIDGE WILL WEAKEN TUE AND GIVE WAY TO LOW PRES TROF PASSAGE TUE NIGHT. IN ITS WAKE...ANOTHER HIGH PRES WILL RIDGE S FROM HUDSON BAY INTO THE UPPER GREAT LAKES WED/THU. WITH PRES GRADIENT ON THE WEAK SIDE...WINDS TUE THRU THU SHOULD BE UNDER 15KT ACROSS LAKE SUPERIOR THOUGH THERE MAY BE SOME STRONGER WINDS ON WED AS THE HIGH BEGINS RIDGING S INTO THE UPPER LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...SRF MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
350 AM CDT SUN APR 26 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CDT SUN APR 26 2015 A VERY PLEASANT DAY IS AHEAD WITH A RIDGE OF HIGH PRESSURE HOLDING STEADY FROM WESTERN ONTARIO THROUGH MINNESOTA AND WISCONSIN. THE SKY WILL BE MAINLY CLEAR TODAY AS WELL AS TONIGHT ALONG WITH A LIGHT NORTHEAST TO EAST WIND. HIGHS THIS AFTERNOON WILL BE SIMILAR THOSE ON SATURDAY WITH LOWER TO MIDDLE 60S FORECAST...WHICH IS VERY CLOSE TO THE SEASONAL NORMAL. THE FORECAST HIGHS TODAY LINE UP WELL WITH MIX-DOWN FROM THE NAM AT 825MB ALONG WITH A SLIGHT SUPER. THE REAL CHALLENGE TODAY IS HOW LOW WILL DEW POINTS DROP... ESPECIALLY ACROSS CENTRAL MN...AND THE CORRESPONDING AFTERNOON MINIMUM HUMIDITY. THE LOW LEVEL NORTHEAST FLOW BROUGHT DEW POINTS IN THE SINGLE DIGITS AND LOWER TEENS INTO NORTHEAST MN SATURDAY EVENING. DEW POINTS NEAR 20 DEGREES ARE NOW PREVALENT ACROSS CENTRAL MN EARLY THIS MORNING. THE NAM AND RAP HAVE A GOOD HANDLE ON THE SITUATION AND LOWER DEW POINTS TO NEAR 15 DEGREES ACROSS MUCH OF CENTRAL MN THIS AFTERNOON WITH AROUND 20 HERE IN THE TWIN CITIES AND WEST CENTRAL WI. THIS RESULTS IN NEAR 15 PERCENT MINIMUM HUMIDITY THIS AFTERNOON ACROSS MUCH OF CENTRAL MN WITH 20 PERCENT HERE IN THE CITIES AND WEST CENTRAL WI. SOUTHERN AREAS OF MN BOTTOM OUT AROUND 25 PERCENT. FORTUNATELY...THE NORTHEAST TO EAST WINDS ARE EXPECTED TO STAY AT OR BELOW 10 MPH THIS AFTERNOON KEEPING THE FIRE THREAT MAINLY IN THE LIMITED RANGE WITH ELEVATED INDICATED ACROSS WEST CENTRAL MINNESOTA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 349 AM CDT SUN APR 26 2015 MILD TEMPERATURES STILL LOOK ON TAP FOR NEXT WEEK...WITH TWO MOISTURE STARVED FRONTS TRAVERSING THE UPPER MS RIVER VALLEY MONDAY NIGHT/TUESDAY AND AGAIN ON FRIDAY. THE TROUBLE MAKER FOR MODEL AGREEMENT THROUGH THE EXTENDED CONTINUES TO BE THE EVOLUTION OF THE DEEP CLOSED H5 LOW OVER NEW ENGLAND NEXT WEEK. MODEL AGREEMENT IS NOT REALLY ALL THAT BAD UNTIL WE GET TO THURSDAY...WHEN THE GFS STARTS TO BECOME MORE AGGRESSIVE WITH PUSHING THIS LOW OUT INTO THE NORTH ATLANTIC...WHICH ALLOWS IT TO BECOME CONSIDERABLY MORE PROGRESSIVE THAN THE GEM/ECMWF WITH THE FLOW ACROSS THE CONUS TO END THE WORK WORK GOING INTO NEXT WEEKEND. FOR MODEL PREFERENCES...WENT WITH A FAIRLY EQUAL BLEND THROUGH THURSDAY...LEANING MORE TOWARD THE LESS PROGRESSIVE ECMWF SOLUTION FOR FRIDAY INTO NEXT WEEKEND. THE LONG TERM WILL START OFF WITH A PICTURE PERFECT DAY ON MONDAY...WITH HIGHS IN THE UPPER 60S/LOWER 70S...SUNNY SKIES AND LIGHT WINDS. MONDAY NIGHT WILL FEATURE A SHORTWAVE MOVING INTO NORTHERN MN...WITH A WEAK COLD FRONT MOVING INTO THE AREA AS WELL. PRECIP POTENTIAL STILL DOES NOT LOOK ALL THAT GREAT FOR THIS FRONT...WITH THE UPPER LOW OVER TEXAS KEEPING ANY MEANINGFUL MOISTURE WELL OF TO OUR SOUTH...WITH CONVERGENCE ALONG THE BOUNDARY LOOKING WEAK AS WELL. THE ECMWF CONTINUES TO BE AN OUTLIER WITH THE STRENGTH OF THIS WAVE AND THE AMOUNT OF PRECIP IT GENERATES AND CONTINUED THE TREND OF FAVORING A DRIER SOLUTION FOR THIS FRONT...WITH JUST SLIGHT CHANCE/LOW CHANCE POPS MENTIONED. WEDNESDAY AND THURSDAY WILL FEATURE ANOTHER DRY RIDGE OF HIGH PRESSURE MOVING THROUGH. ONLY CHANGE MADE TO BLENDED FORECAST HERE WAS TO LOWER DEWPOINTS SOME BOTH DAYS TO ACCOUNT FOR THE MIXING POTENTIAL. ALSO BLENDED IN SOME BIAS CORRECTED NUMBERS INTO THE HIGHS BOTH DAYS TO BOOST THEM BY A FEW DEGREES EACH DAY...WITH WIDESPREAD HIGHS IN THE 70S EXPECTED FOR WED/THU. NEXT ISSUE IN THE EXTENDED COMES FRIDAY WITH THE PASSAGE OF THE NEXT COLD FRONT. GIVEN THE DIFFERENCES IN THE HANDLING OF THE NEW ENGLAND H5 LOW MENTIONED IN THE SECOND PARAGRAPH...THE GFS IS QUITE A BIT FASTER WITH BRINGING THE FRONT THROUGH THAN THE ECMWF. THIS SPREAD IN THE FRONTS TIMING EXPLAINS THE NICE SMEARING OF SLIGHT CHANCE POPS ACROSS THE AREA ON FRIDAY. THIS FRONT DOES HAVE A COUPLE OF FACTORS THAT CAN GIVE ONE A LITTLE BIT MORE HOPE FOR SEEING PRECIP WITH THIS BOUNDARY AS OPPOSED TO THE ONE FOR MONDAY NIGHT. NUMBER ONE...THERE WILL BE NO UPPER LOW OVER TEXAS INTERCEPTING MOISTURE STREAMING NORTH. ALSO MAKING THE PRECIP POTENTIAL LOOK SLIGHTLY BETTER IS THAT THE LOW LEVEL CONVERGENCE LOOKS BETTER ON FRIDAY AND THIS FRONT ACTUALLY HAS SOME H85 FLOW AND MOISTURE TRANSPORT OUT AHEAD OF IT. STILL...THE AIRMASS IT WILL BE DISPLACING AGAIN LOOKS INCREDIBLY DRY AND WITH INSTABILITY LACKING...ANYTHING WE DO SEE LOOKS PRETTY LIGHT AT THIS POINT. AS FOR FIRE WEATHER CONCERNS NEXT WEEK...HUMIDITIES EACH AFTERNOON LOOK TO GET DOWN INTO THE 20S/30S. WINDS STILL LOOK LIGHT THOUGH THROUGH WEDNESDAY...BUT THURSDAY AND FRI WILL FEATURE STRONGER WINDS AND IF THE MOISTURE RETURN ENDS UP BEING RATHER LACKING...WE COULD HAVE FIRE WEATHER CONCERNS ONCE AGAIN. AT THIS POINT...THURSDAY LOOKS TO BE THE DAY THAT HAS THE GREATEST POTENTIAL TO GENERATE RED FLAG CONDITIONS AS OUR SE WINDS WILL BE EMANATING FROM A VERY DRY SFC RIDGE CENTERED OVER THE GREAT LAKES....WHILE FRIDAY AT THIS POINT LOOKS TO FEATURE HIGHER DEWPS WITH THE PASSING FRONT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1029 PM CDT SAT APR 25 2015 VFR CONDS THROUGHOUT THIS TAF SET. SKC CONDS WILL PREVAIL THRU TMRW EVE. E TO NE WINDS WILL SETTLE CLOSE TO 5 KT OVERNIGHT THEN INCRS TO THE 5-10 KT RANGE DURG THE DAY TMRW. KMSP...NO SIGNIFICANT WX IMPACTS EXPECTED THIS TAF SET. /OUTLOOK FOR KMSP/ MON...VFR. WINDS NNE 5-10 KT. TUE...VFR. WINDS NW 5-10 KT. WED...VFR. WIND N 5-10 KT. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...RAH LONG TERM...MPG AVIATION...JPC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1258 AM EDT SUN APR 26 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE EAST ALONG A STALLED FRONT ACROSS THE AREA TONIGHT THEN OFFSHORE SUNDAY...PULLING A COLD FRONT THROUGH THE AREA FROM THE NORTH. HIGH PRESSURE BUILDS OVER THE AREA EARLY NEXT WEEK BEFORE ANOTHER LOW PRESSURE SYSTEM AFFECTS THE REGION DURING THE MIDDLE OF THE WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1255 AM SUNDAY...SHOWERS HAVE MOVED OFF OF THE COAST AS OF 0445Z AND NOW THERE WILL BE A LULL IN THE PRECIPITATION UNTIL EARLY SUNDAY MORNING. WILL LOWER POPS TO SLIGHT CHANCE AND CALL FOR PATCHY LIGHT DRIZZLE ALONG WITH A SLIGHT CHANCE OF A SHOWER. PATCHES OF FOG ARE ALSO EXPECTED BUT NOT ANTICIPATING WIDESPREAD DENSE FOG OVERNIGHT. UPSTREAM CONVECTION OVER EASTERN TN/KY AND SOUTHWEST VA IS FORECAST TO MOVE INTO THE COASTAL PLAIN OF EASTERN NC AROUND 10Z SUNDAY. WILL INCREASE POPS TO LIKELY MOST ZONES THROUGH SUNDAY MORNING BASED ON LATEST HRRR RUN AND CONSENSUS OF THE 00Z GFS/NAM MODELS. LOW PRESSURE DEVELOPING OFF OF THE NC LATE TONIGHT WILL REINFORCE THE HIGH PRES WEDGE EAST OF THE MTNS WITH WIDESPREAD LOW CLOUDS CONTINUING THROUGH SUNDAY. TEMPS MAY FALL A FEW DEGS FROM CURRENT LEVELS WITH LOWS FROM AROUND 50 N TO UPR 50S S EXPECTED. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 AM MONDAY/... AS OF 300 PM SATURDAY...LOW PRES DEEPENING OFFSHORE WILL PULL COLD FRONT THROUGH AREA FROM N BY EARLY AFTN...AND MODELS INDICATE WDPSRD LIGHT QPF THREAT 12Z-18Z. INCREASED POPS TO LIKELY MOST OF AREA FOR MORNING. CLOUDS AND PCPN WILL HOLD TEMPS TO UPR 50S NRN SECTIONS WHILE SRN SECTIONS MAY REACH UPR 60S BEFORE FRONTAL PASSAGE. && .LONG TERM /MONDAY THROUGH SUNDAY/... AS OF 3 PM SAT...SFC HIGH PRESSURE WILL EXTEND INTO THE REGION FROM THE NW SUN NIGHT INTO WED...WHILE SFC LOW PUSHES ENE OFF THE NC COAST SUN NIGHT AND MON. PRECIP WILL TAPER OFF QUICKLY SUN EVENING AS LOW PUSHES FURTHER OFF THE COAST. BELOW NORMAL TEMPS EXPECTED THROUGH MOST OF THE PERIOD...WITH LOW LEVEL THICKNESS VALUES SUPPORTING HIGHS IN THE 60S THROUGH THU...AND LOWS IN THE LOW/MID 40S TO MID 50S. VERT STACKED LOW CURRENTLY OVER THE NE US WILL LINGER THROUGH THE BEGINNING OF NEXT WEEK...GRADUALLY RETROGRADING OFF THE MID-ATLANTIC COAST THROUGH MID-WEEK. PIECES OF UPPER LEVEL ENERGY WILL ROTATE AROUND THE BASE OF THE UPPER LOW AND TROUGH MON AND TUE. EXPECT DRY CONDITIONS MON AND TUE...THOUGH CANNOT RULE OUT AN ISOLATED SHOWER GIVEN THE IMPULSES MOVING THROUGH THE FLOW ALOFT. LARGE MODEL DIFFERENCES CONTINUE MID TO LATE WEEK...AND BELOW AVERAGE CONFIDENCE CONTINUES. AN AREA OF LOW PRESSURE IS EXPECTED TO DEVELOP IN THE GULF OF MEXICO TUE...THEN MOVE UP THE SE COAST WED INTO THU. ECMWF CONTINUES TO DEVELOP A MUCH STRONGER LOW...BOMBING OUT OFF THE NC COAST. WHILE THE GFS SHOWS A MUCH WEAKER LOW...KEEPING IT SUPPRESSED FURTHER TO THE SOUTH OF NC OFF THE SE COAST. WILL CONTINUE TO FOLLOW TRENDS OF PREVIOUS FORECAST AND WPC...WITH A WEAK LOW MOVING OFF THE COAST LATE WED INTO THURSDAY. WILL CONTINUE TO CAP POPS AT 50 PERCENT WED AND THU GIVEN THE CONTINUED UNCERTAINTY. ADDITIONAL IMPACTS COULD BE FELT ACROSS THE REGION LATE WEEK...DEPENDENT ON EVENTUAL TRACK AND STRENGTH OF THE LOW. TEMPS GRADUALLY MODERATE FRI INTO THE WEEKEND...WITH SFC HIGH PRESSURE BUILDING IN FROM THE WEST. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... SHORT TERM /THROUGH SUNDAY NIGHT/... ASOF 1255 AM SUNDAY...HIGH CONFIDENCE IN IFR CONDITIONS PERSISTING INTO EARLY SUNDAY AFTERNOON. A STALLED FRONT OVER THE SOUTHERN FORECAST AREA WILL PUSH SLOWLY SOUTH OVERNIGHT AND REINFORCE THE HIGH PRES WEDGE PATTERN INLAND. CEILINGS WILL REMAIN IN THE IFR RANGE THROUGH EARLY SUNDAY AFTERNOON THEN LIFT TO MVFR UNTIL AROUND 00Z WHEN CONDITIONS SHOULD IMPPROVE TO VFR. SCATTERED SHOWER AND THUNDERSTORM ACTIVITY WELL TO THE WEST LATE TONIGHT IS FORECAST TO MOVE ACROSS THE TAF SITES 11-15Z SUNDAY MORNING OTHERWISE EXPECTING ONLY SPOTTY LIGHT PRECIPITATION THE NEXT 24 HOURS. LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 3 PM SAT...SUB-VFR CONDITIONS EXPECTED TO LINGER SUN NIGHT GRADUALLY IMPROVING BY EARLY MONDAY MORNING. PRED VFR MON THROUGH TUE NIGHT. INCREASING RAIN CHANCES WED AND THU...WITH PERIODS OF SUB-VFR POSSIBLE AS AN AREA OF LOW PRESSURE WILL IMPACT THE REGION. && .MARINE... SHORT TERM /THROUGH SUNDAY/... AS OF 1255 AM SUNDAY...NO CHANGES TO PREVIOUS FORECAST THINKING. LOW PRESSURE MOVING EAST ALONG STALLED BNDRY OVER FAR SOUTHERN WATERS LATE THIS EVENING MAINTAINING A LIGHT TO MODERATE NE/E FLOW NORTH OF THE BNDRY. THE LOW MOVES OFF THE COAST EARLY SUNDAY AND GUSTY N/NE WINDS WILL DEVELOP AND SPREAD N TO S OVER WATERS AS LOW DEEPENS OFFSHORE ON SUNDAY. USED MODEL BLEND TOWARD WEAKER GFS AND ECMWF...BUT WILL POST SCA FOR NRN AND CENTRAL WATERS WITH FREQUENT GUSTS TO 25 KT LIKELY IN AFTN...AND SEAS BUILDING TO 4 TO 6 FT LATE. LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AS OF 3 PM SAT...GUSTY NORTHERLY WINDS 15-25KT AND ELEVATED SEAS 4-7FT WILL START OFF THE PERIOD SUN NIGHT. SURGE GRADUALLY DIMINISHING MON MORNING WITH SEAS GRADUALLY SUBSIDING TO 3-5FT BY EARLY AFTERNOON. SFC HIGH PRESSURE WILL BUILD IN FROM THE NW SUN NIGHT THROUGH MID- WEEK. GRADIENT TIGHTENS MON NIGHT INTO EARLY TUE...AND MODELS IN GOOD AGREEMENT SHOWING NWLY SURGE 15-25KT WITH SEAS BUILDING UP TO 6FT ON THE OUTER WATERS. PERIOD OF SCA CONDITIONS LIKELY...MAINLY NORTH OF OCRACOKE. LARGE MODEL DIFFERENCES CONTINUE MID TO LATE WEEK...AND BELOW AVERAGE CONFIDENCE CONTINUES. AN AREA OF LOW PRESSURE IS EXPECTED TO DEVELOP IN THE GULF OF MEXICO TUE...THEN MOVE UP THE SE COAST WED INTO THU. INCREASING WINDS AND BUILDING SEAS WED AND THU. ELY FLOW BY WED AFTERNOON...INCREASING TO 10-20KT WED NIGHT WITH SEAS 2-4FT. STRONGER WINDS EXPECTED THU WITH SEAS BUILDING TO 4-6FT. CONFIDENCE REMAINS LOWER THAN AVERAGE FOR WED AND THU...BUT SCA CONDITIONS LIKELY TO DEVELOP WITH THE POTENTIAL FOR GALES DEPENDING ON EVENTUAL TRACK AND STRENGTH OF LOW PRESSURE. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO NOON EDT MONDAY FOR AMZ152-154. SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM EDT MONDAY FOR AMZ150-156. SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 11 PM EDT THIS EVENING FOR AMZ135. && $$ SYNOPSIS...JBM NEAR TERM...JME/BTC/JBM SHORT TERM...JBM LONG TERM...CQD AVIATION...JME/CQD MARINE...JME/JBM/CQD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1139 PM CDT SAT APR 25 2015 .UPDATE... ISSUED AT 1139 PM CDT SAT APR 25 2015 NO CHANGES TO 10 PM UPDATE PLANNED. UPDATE FOR AVIATION DISCUSSION ONLY. UPDATE ISSUED AT 1020 PM CDT SAT APR 25 2015 FORECAST CHALLENGE WILL BE OVERNIGHT LOWS. LATEST RUC GUIDANCE DOING WELL WITH INHERITED MINIMUM TEMP FCST SO HAVE USED RUC FOR GUIDANCE ON WIND AND HOURLY TEMPS. ADJUSTMENTS TO SKY MADE AT 7 PM WORKED OUT WELL SO NO FURTHER CHANGES EXPECTED. UPDATE ISSUED AT 655 PM CDT SAT APR 25 2015 FORECAST UPDATE WILL ADDRESS MINOR SKY ISSUES...WITH EASTERN NORTH DAKOTA CLEARING OUT A BIT MORE RAPIDLY THAN PREV FCST INDICATED. WITH MID LVL DECK WELL OFF TO WEST...WILL DECREASE SKY OVER ERN ND THROUGH THE NIGHT. NO OTHER CHANGES MADE AT THIS TIME. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 302 PM CDT SAT APR 25 2015 TEMPERATURES AND CLOUD COVER WILL BE THE MAIN CONCERNS FOR THE PERIOD. CLOUDS HAVE MOVED MOSTLY WEST OF THE RED RIVER AS DRIER AIR HAS BEEN COMING IN FROM THE EAST UNDER HIGH PRESSURE. THERE HAVE BEEN SOME CU REDEVELOPMENT IN THE CENTRAL RED RIVER VALLEY...BUT FOR THE MOST PART THE MINNESOTA SIDE HAS BECOME PARTLY CLOUDY WITH SOUTHEASTERN NORTH DAKOTA STILL SOCKED IN WITH STRATUS. THE RAP 925-850MB RH FIELD HAS BEEN DOING DECENT WITH THE CLOUD COVER...AND IT HAS THE HIGHER RH VALUES SLOWLY MOVING WEST THROUGH TONIGHT. THERE WILL ALSO BE SOME HIGHER CLOUDS COMING IN THROUGH WESTERN ND AS A SHORTWAVE TROUGH MOVES INTO THE CANADIAN ROCKIES. THINK THE CLOUDS AND WINDS AROUND 10 KTS WILL KEEP TEMPS IN THE WESTERN COUNTIES IN THE 40S WHILE THE EAST WILL HAVE LIGHT WINDS AND CLEAR SKIES...DROPPING DOWN BELOW FREEZING TONIGHT. THE DRY AIR WILL CONTINUE TO COME IN AS HIGH PRESSURE REMAINS ANCHORED TO OUR NORTHEAST. THE MODELS SHOW A WEAK TROUGH OF LOW PRESSURE ENTERING CENTRAL ND...BUT ALL HAVE THE PRECIP ALONG THAT BOUNDARY DISSIPATING AS IT MOVES EAST. THIS SEEMS REASONABLE GIVE THE DRY ENVIRONMENT AND NOT MUCH UPPER FORCING...SO WILL KEEP POPS OUT UNTIL AFTER 00Z MONDAY. TEMPS ON SUNDAY WILL BE A BIT WARMER THAN TODAY WITH HIGHER CLOUDS AND A SLIGHTLY WARMER AIR MASS. KEPT READINGS IN THE 60S. SUNDAY NIGHT...THE NORTHERN BRANCH SHORTWAVE TROUGH WILL PROGRESS INTO SASKATCHEWAN/MANITOBA...WITH THE WEAK TROUGH AXIS MOVING INTO THE FAR WESTERN CWA. THERE WILL BE SOME IMPROVING UPPER LEVEL SUPPORT AS THE SYSTEM MOVES EAST...BUT IT WILL BE FIGHTING AGAINST CONTINUED DRY AIR COMING IN FROM THE SFC HIGH TO THE EAST. INCLUDED SOME SHOWERS GETTING INTO OUR FAR NORTHWESTERN CWA AFTER MIDNIGHT...BUT THINK THAT THE BULK OF PRECIP WILL HOLD OFF UNTIL MONDAY. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 302 PM CDT SAT APR 25 2015 MONDAY THROUGH TUESDAY...SPLIT FLOW CONTINUES OVER NORTH AMERICA WITH THE NORTHERN BRANCH SHORTWAVE MOVING THROUGH SOUTHERN CANADA TO OUR NORTH. THIS WILL PUSH A WEAK SFC TROUGH AXIS INTO THE CWA MONDAY AND MONDAY NIGHT...WITH SOME GOOD Q VECTOR CONVERGENCE FOR RISING MOTION. WILL CONTINUE TO KEEP POPS HIGH THROUGH MONDAY AND MONDAY NIGHT ALONG THE SFC TROUGH AXIS...WITH MAINLY LIGHT RAIN SHOWERS EXPECTED. LEANED TOWARDS THE DRIER GFS/NAM RATHER THAN THE WETTER INTERNATIONAL MODELS GIVEN THE TENDENCY LATELY FOR OVERDOING RAIN. WE SHOULD DRY OUT BY TUESDAY AS THE SFC TROUGH MOVES OFF TO THE EAST. HIGHS ON MONDAY WILL BE IN THE 60S IN MOST OF THE CWA BUT THE NORTHWESTERN COUNTIES COULD STAY IN THE 50S WITH RAIN COMING IN EARLIER. MONDAY NIGHT WILL RANGE FROM THE UPPER 30S TO LOW 40S AND TUESDAY SHOULD BE IN THE 60S ACROSS THE REGION. TUESDAY NIGHT THROUGH FRIDAY...MODELS SHOW A BUILDING UPPER RIDGE THROUGH THE REST OF THE PERIOD. GEM NOT SHOWING AS STRONG A RIDGE AS THE OUTLIER...SO FAVORED AN ECMWF/GFS BLEND FOR THIS FORECAST. THUS...EXPECT TEMPERATURES TO BE ON THE WARMER SIDE...WITH HIGHS POSSIBLY REACHING CLOSE TO THE MID 70S. OTHERWISE...THE PERIOD WILL REMAIN ON THE DRY SIDE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1139 PM CDT SAT APR 25 2015 SOUTHEAST WINDS WILL AND AN UPPER RIDGE WILL KEEP DRY CONDS IN THE AERODROMES FOR THE VALLEY AND SITES IN MINNESOTA. A LINE OF SHOWERS OVER CNTRL ND MAY GET INTO DVL AREA TOMORROW EVENING...BUT DRY AIR MASS WILL HELP HOLD THOSE SHOWERS BACK. PUT A MENTION (VCSH) IN FOR TOMORROW EVENING AS CONFIDENCE OF ON STATION PRECIP IS TOO LOW THIS FAR OUT. CIGS LIKELY WILL BE VFR OR UPPER MVFR RANGE TOMORROW EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...SPEICHER SHORT TERM...JR LONG TERM...JR/HOPKINS AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1045 AM CDT SUN APR 26 2015 .UPDATE... ISSUED AT 1041 AM CDT SUN APR 26 2015 HIGH PRESSURE BUILDING BACK INTO THE REGION WITH A SFC RIDGE AXIS JUST TO THE WEST. NORTH/NORTHEASTERLY WINDS CONTINUE THROUGH THE DAY, GETTING A LITTLE GUSTY LATER THIS AFTERNOON WITH A LITTLE BIT OF MIXING. MODELS HINTING AT A LITTLE BIT OF MOISTURE BTWN 5000-8000 FT OR SO. CU RULE NOT PARTICULARLY STRONG UNDER THE RIDGE AND MIXING MAY INHIBIT A LOT OF CU...BUT STILL POSSIBLE TO SEE A FEW LATER THIS AFTERNOON. OTHERWISE QUIET, AND NO SIGNIFICANT UPDATES ANTICIPATED AT THIS TIME. && .SHORT TERM...(TODAY) ISSUED AT 330 AM CDT SUN APR 26 2015 LOW CLOUDS CONTINUE TO GRADUALLY WORK THEIR WAY SOUTH THROUGH CENTRAL AND EAST CENTRAL IL EARLY THIS MORNING AS DRIER AIR ADVECTS FROM THE NORTHEAST. MOSTLY CLOUDY CONDITIONS WILL LINGER IN SOUTHEAST IL FROM DAYBREAK UNTIL MID-MORNING. PLENTY OF LOW LEVEL MIXING IN THE LOWER ATMOSPHERE LATE THIS MORNING THROUGH THE AFTERNOON WILL RESULT IN NORTHEAST WINDS GUSTING CLOSE TO 20 MPH ESPECIALLY EAST OF THE I-55 CORRIDOR. DESPITE PLENTY OF SUNSHINE BY AFTERNOON...HIGHS TODAY WILL MAINLY BE AROUND 60 DEGREES DUE TO THE DEEP LOW LEVEL NORTHEAST FLOW. .LONG TERM...(TONIGHT THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN APR 26 2015 FAIRLY QUIET WEATHER ON TAP ACROSS THE FORECAST AREA MUCH OF THE WEEK. PERSISTENT NORTHEAST FLOW TO KEEP DRY CONDITIONS IN PLACE... WITH HIGH TEMPERATURES RISING A COUPLE DEGREES EACH DAY UNTIL WE FINALLY GET NEAR OR JUST ABOVE NORMAL BY THE END OF THE WORK WEEK. UPPER LOW CURRENTLY IN THE PROCESS OF CLOSING OFF OVER WESTERN ARIZONA...AND THIS WILL BE TRACKING ACROSS THE SOUTHERN U.S. OVER THE NEXT FEW DAYS. ALL OF THE MODELS KEEP THE ASSOCIATED MOISTURE SOUTH OF THE OHIO VALLEY. A SHORTWAVE WILL ALSO BE TRACKING ALONG THE CANADIAN BORDER...AND AS PREVIOUS MODEL RUNS INDICATED, A SMALL CLOSED LOW WILL PINCH OFF IN THE SOUTHERN PART OF THE WAVE. THE ECMWF AND CANADIAN MODELS HAVE THIS SMALL LOW DROPPING ACROSS MINNESOTA AND IOWA TUESDAY NIGHT...WHILE THE TAIL END OF THE NAM BRINGS THIS INTO NORTHERN ILLINOIS AND THE GFS PROGRESSES THE WAVE WELL EAST BEFORE THE LOW CAN FORM. NET RESULT OF ALL OF THIS IS FOR DRY CONDITIONS MID WEEK. AS WE GET LATER IN THE WEEK...UPPER RIDGING WILL BUILD NORTHEAST ACROSS THE PLAINS INTO MANITOBA...WHILE GENERAL BROAD TROUGHING CONTINUES ACROSS THE EASTERN U.S. THIS RIDGE FLATTENS BY FRIDAY AS THE NORTHERN STREAM BECOMES MORE ACTIVE ALONG THE CANADIAN BORDER. BOTH THE GFS AND ECMWF BRING A SURFACE BOUNDARY THROUGH THE AREA FRIDAY NIGHT AND SATURDAY...WITH SOME LIGHT PRECIPITATION. THE SOLUTIONS BEGIN TO DIVERGE BY EVENING...AS THE GFS BRINGS A STRONGER UPPER WAVE AND SURFACE FRONT THROUGH SATURDAY NIGHT WITH SHOWERS AND THUNDERSTORMS...ALTHOUGH THE ECMWF DOES HINT AT POTENTIAL MCS ACTIVITY AS WELL. WITH THE MORE DIVERGENT SOLUTIONS...HAVE KEPT THE LATE WEEKEND FORECAST DRY FOR NOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 638 AM CDT SUN APR 26 2015 THE BACK EDGE OF MVFR/IFR CLOUDS IS JUST SOUTH OF I-70 AS OF 1130Z. A DEEP NORTHEAST FLOW IN THE LOWER ATMOSPHERE WILL CONTINUE TO BRING DRY AIR INTO CENTRAL IL TODAY AND PUSH THE LOW CLOUDS FARTHER AWAY FROM THE REGION. HAVE SEEN MVFR VISIBILITY JUST DEVELOP IN EAST CENTRAL IL...SO WILL CONTINUE THIS IN THE TAF FOR KCMI UNTIL 14Z WHEN INCREASING WIND SPEEDS WILL MIX OUT THE LIGHT FOG. NAM FORECAST SOUNDINGS INDICATE THAT THE LOW LEVEL MIXING WILL RESULT IN A TREND TOWARD SOMEWHAT GUSTY WINDS IN THE 15-20 KT RANGE FROM LATE MORNING THROUGH THE AFTERNOON IN ALL OF CENTRAL AND EASTERN IL. THE RAP AND NAM MODELS BOTH INDICATE THAT THERE SHOULD BE ENOUGH MOISTURE FOR AT LEAST SCATTERED CUMULUS LATER THIS MORNING AND ESPECIALLY DURING THE AFTERNOON. THE LOWER LEVELS WILL GO THROUGH THE TYPICAL EARLY EVENING DECOUPLING WITH A CLEAR SKY AND VERY LIGHT WIND OVERNIGHT. AM NOT EXPECTING ANY FOG AT THIS POINT SINCE THE BREEZY CONDITIONS AND MIXING THIS AFTERNOON SHOULD HELP DRY OUT THE LOWEST LAYERS AND SURFACE. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HJS SHORT TERM...MILLER LONG TERM...GEELHART AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS LINCOLN IL
638 AM CDT SUN APR 26 2015 .SHORT TERM...(TODAY) ISSUED AT 330 AM CDT SUN APR 26 2015 LOW CLOUDS CONTINUE TO GRADUALLY WORK THEIR WAY SOUTH THROUGH CENTRAL AND EAST CENTRAL IL EARLY THIS MORNING AS DRIER AIR ADVECTS FROM THE NORTHEAST. MOSTLY CLOUDY CONDITIONS WILL LINGER IN SOUTHEAST IL FROM DAYBREAK UNTIL MID-MORNING. PLENTY OF LOW LEVEL MIXING IN THE LOWER ATMOSPHERE LATE THIS MORNING THROUGH THE AFTERNOON WILL RESULT IN NORTHEAST WINDS GUSTING CLOSE TO 20 MPH ESPECIALLY EAST OF THE I-55 CORRIDOR. DESPITE PLENTY OF SUNSHINE BY AFTERNOON...HIGHS TODAY WILL MAINLY BE AROUND 60 DEGREES DUE TO THE DEEP LOW LEVEL NORTHEAST FLOW. .LONG TERM...(TONIGHT THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN APR 26 2015 FAIRLY QUIET WEATHER ON TAP ACROSS THE FORECAST AREA MUCH OF THE WEEK. PERSISTENT NORTHEAST FLOW TO KEEP DRY CONDITIONS IN PLACE... WITH HIGH TEMPERATURES RISING A COUPLE DEGREES EACH DAY UNTIL WE FINALLY GET NEAR OR JUST ABOVE NORMAL BY THE END OF THE WORK WEEK. UPPER LOW CURRENTLY IN THE PROCESS OF CLOSING OFF OVER WESTERN ARIZONA...AND THIS WILL BE TRACKING ACROSS THE SOUTHERN U.S. OVER THE NEXT FEW DAYS. ALL OF THE MODELS KEEP THE ASSOCIATED MOISTURE SOUTH OF THE OHIO VALLEY. A SHORTWAVE WILL ALSO BE TRACKING ALONG THE CANADIAN BORDER...AND AS PREVIOUS MODEL RUNS INDICATED, A SMALL CLOSED LOW WILL PINCH OFF IN THE SOUTHERN PART OF THE WAVE. THE ECMWF AND CANADIAN MODELS HAVE THIS SMALL LOW DROPPING ACROSS MINNESOTA AND IOWA TUESDAY NIGHT...WHILE THE TAIL END OF THE NAM BRINGS THIS INTO NORTHERN ILLINOIS AND THE GFS PROGRESSES THE WAVE WELL EAST BEFORE THE LOW CAN FORM. NET RESULT OF ALL OF THIS IS FOR DRY CONDITIONS MID WEEK. AS WE GET LATER IN THE WEEK...UPPER RIDGING WILL BUILD NORTHEAST ACROSS THE PLAINS INTO MANITOBA...WHILE GENERAL BROAD TROUGHING CONTINUES ACROSS THE EASTERN U.S. THIS RIDGE FLATTENS BY FRIDAY AS THE NORTHERN STREAM BECOMES MORE ACTIVE ALONG THE CANADIAN BORDER. BOTH THE GFS AND ECMWF BRING A SURFACE BOUNDARY THROUGH THE AREA FRIDAY NIGHT AND SATURDAY...WITH SOME LIGHT PRECIPITATION. THE SOLUTIONS BEGIN TO DIVERGE BY EVENING...AS THE GFS BRINGS A STRONGER UPPER WAVE AND SURFACE FRONT THROUGH SATURDAY NIGHT WITH SHOWERS AND THUNDERSTORMS...ALTHOUGH THE ECMWF DOES HINT AT POTENTIAL MCS ACTIVITY AS WELL. WITH THE MORE DIVERGENT SOLUTIONS...HAVE KEPT THE LATE WEEKEND FORECAST DRY FOR NOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 638 AM CDT SUN APR 26 2015 THE BACK EDGE OF MVFR/IFR CLOUDS IS JUST SOUTH OF I-70 AS OF 1130Z. A DEEP NORTHEAST FLOW IN THE LOWER ATMOSPHERE WILL CONTINUE TO BRING DRY AIR INTO CENTRAL IL TODAY AND PUSH THE LOW CLOUDS FARTHER AWAY FROM THE REGION. HAVE SEEN MVFR VISIBILITY JUST DEVELOP IN EAST CENTRAL IL...SO WILL CONTINUE THIS IN THE TAF FOR KCMI UNTIL 14Z WHEN INCREASING WIND SPEEDS WILL MIX OUT THE LIGHT FOG. NAM FORECAST SOUNDINGS INDICATE THAT THE LOW LEVEL MIXING WILL RESULT IN A TREND TOWARD SOMEWHAT GUSTY WINDS IN THE 15-20 KT RANGE FROM LATE MORNING THROUGH THE AFTERNOON IN ALL OF CENTRAL AND EASTERN IL. THE RAP AND NAM MODELS BOTH INDICATE THAT THERE SHOULD BE ENOUGH MOISTURE FOR AT LEAST SCATTERED CUMULUS LATER THIS MORNING AND ESPECIALLY DURING THE AFTERNOON. THE LOWER LEVELS WILL GO THROUGH THE TYPICAL EARLY EVENING DECOUPLING WITH A CLEAR SKY AND VERY LIGHT WIND OVERNIGHT. AM NOT EXPECTING ANY FOG AT THIS POINT SINCE THE BREEZY CONDITIONS AND MIXING THIS AFTERNOON SHOULD HELP DRY OUT THE LOWEST LAYERS AND SURFACE. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...MILLER LONG TERM...GEELHART AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
948 AM MDT SUN APR 26 2015 .UPDATE... ISSUED AT 948 AM MDT SUN APR 26 2015 UPDATE ISSUED TO DECREASE PRECIP COVERAGE THRU REST OF MORNING HRS BASED ON LATEST RADAR TRENDS. HAVE OPTED TO REMOVE MENTION OF HIGHER POPS/THUNDER FROM THE ENTIRE CWA FORECAST REST OF MORNING INTO THE EARLY AFTERNOON. THE MORNING HRS HERE IN THE CWA HAVE BEEN PERSISTENT FOG AND MAINLY DRIZZLE. MOST APPRECIABLE RETURNS HAVE BEEN FOCUSED OVER THE CENTRAL ROCKIES AROUND THE UPPER LOW. EASTERLY FLOW OVER THE CWA HAVE AIDED IN UPSLOPE CONDITIONS KEEPING PRECIP FOCUSED WEST OF OUR CWA BORDERS. AM EXPECTING AN INCREASE LATER IN THE AFTERNOON THOUGH AS UPPER LOW PIVOTS OUT ONTO THE PLAINS. HAVE SHOWN INCREASING POPS TOWARDS THAT TIMEFRAME AS WELL AS A FEW HOURS WHERE THUNDER IS POSSIBLE WITH INCREASED INSTABILITY WITH LOW PROXIMITY. REST OF FORECAST FOR TEMPS/WINDS REMAIN ON TRACK. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 419 AM MDT SUN APR 26 2015 MAIN FORECAST CONCERNS WILL BE GRADIENT OF PRECIPITATION CHANCES INTO MONDAY AND HIGH TEMPERATURES TODAY/MONDAY. SATELLITE SHOWING THE FLOW HAS BECOME MORE AMPLIFIED FROM THE PACIFIC INTO THE WESTERN ATLANTIC OVER THE LAST 24 HOURS. SPLIT FLOW CONTINUES OVER THE WESTERN PORTION OF COUNTRY WITH EXPECTED SOUTHERN CUTOFF LOW NOW STARTING TO MOVE INTO ARIZONA/NEW MEXICO. NATURE OF FLOW WHICH IN SOME RESPECTS IS RETROGRESSING A LITTLE WOULD INDICATE THE PATTERN IS GOING TO BE SLOW TO CHANGE. COLD FRONT HAS MOVED THROUGH WITH UPSLOPE WINDS AND STRATUS ENTRENCHED ACROSS THE AREA. AT JET LEVEL...MODELS HANDLED THIS WELL THE GFS THE WORST AND TOO STRONG. AT MID LEVELS...MODELS WERE HAVING A LITTLE TROUBLE WITH THE DEVELOPING WESTERN TROUGH. THEY TENDED TO BE TOO DEEP WITH THE NAM THE WORST. OUTSIDE OF THIS THE NAM WAS NOT DOING TOO BAD. OVERALL THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND UKMET. THE CANADIAN WERE DOING THE WORST. MODELS HAD SURFACE LOW TO OUR SOUTHWEST TOO FAR NORTH. THE RUC AND ECMWF WERE DOING THE BEST. THE MODELS WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD WITH THE GFS...CANADIAN...SREF AND NAM DOING THE BEST. TODAY/TONIGHT...MAJORITY OF CONVECTION DURING THE EVENING STAYED MOSTLY TO THE WEST. UPSTREAM SOUNDINGS/UPPER AIR ANALYSIS TO THE SOUTH THROUGH THE WEST NOT PAINTING/SUPPORTING A WET FORECAST WITH A VERY DEEP DRY LAYER AND WHAT MOISTURE THERE IS AT 700 MB AT ITS LOWEST. IT LOOKS LIKE A LOT OF DRY AIR GETS PULLED INTO THE AREA BEFORE THE ARRIVAL OF ANY SIGNIFICANT DYNAMICS. UPPER AIR ANALYSIS SUPPORTS A RATHER FAR SOUTH SOLUTION OF THE EVENTUAL UPPER LOW WITH THE LARGEST HEIGHT FALLS OVER ARIZONA. NEW MODEL SUITE SUPPORTS WHAT THE ANALYSIS IS SHOWING. MAIN AREA OF PRECIPITATION HAS STAYED TO THE NORTH AND WEST OF THE AREA ALL NIGHT WITH ONLY A FEW RAIN SHOWERS ALONG WITH AREAS OF DRIZZLE AND FOG IN THE SATURATED LOW LEVELS. DYNAMICS TO OUR WEST BEGINS TO AFFECT MOST OF THE WESTERN TWO THIRDS OF THE FORECAST AREA THROUGH THE MIDDLE OF THE DAY BEFORE SOME DRYING ALOFT OCCUR AS THE LIFT MOVES AWAY FROM THE AREA. BASED ON THE LATEST MODEL DATA AND OBSERVATIONAL TRENDS...SHOULD HAVE A WIDE VARIETY OF WEATHER THIS MORNING. AREAS OF FOG AND DRIZZLE ALONG WITH SOME RAIN SHOWERS SHOULD PERSIST DURING THE MORNING. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT WITH ELEVATED CAPE AND FAVORABLE LAPSE RATES IN PLACE. WILL BE A LULL IN THE PRECIPITATION FOR MOST OF THE REST OF THE DAY. AS HAS BEEN THE CASE THE LAST FEW DAYS...THE FAR WEST AND SOUTHWEST WILL HAVE THE BEST CHANCE OF PRECIPITATION DURING THIS TIME. CLOUD COVER SHOULD STAY THICK MOST OF THE DAY WITH MAYBE SOME CLEARING IN THE FAR EASTERN PORTION AS A LITTLE DRIER AIR MOVES IN TO THERE. KEPT THE COOLER TEMPERATURES IN PLACE WITH COOLEST READINGS IN THE FAR WEST WHERE TEMPERATURES MAY NEED NOT GET OUT OF THE 40S. SOUTHERN CUTOFF LOW GETS ORGANIZED AND IN A DECENT POSITION TO GIVE THE AREA SOME LIGHT PRECIPITATION LATER THIS AFTERNOON INTO TONIGHT...ESPECIALLY IN THE SOUTHWEST THIRD TO HALF. THE BEST CHANCE OF PRECIPITATION LOOKS TO OCCUR FROM EARLY EVENING TO NEAR 09Z AS THE BEST/DEEPEST MOISTURE GETS IN PLACE. AFTER THAT THE MOISTURE AND PRECIPITATION STARTS ITS GRADUAL SLIDE TO THE SOUTH AND EAST. MONDAY/MONDAY NIGHT...UPPER SYSTEM AND ASSOCIATED MOISTURE AND PRECIPITATION CONTINUES ITS SHIFT SOUTH AND EAST AS THE EXITING SYSTEM MOVES AWAY. ONCE AGAIN THE FAR SOUTH AND SOUTHWEST WILL HAVE THE BEST CHANCE FOR LIGHT PRECIPITATION. CLEARING WILL ALSO BEGIN WITH MOST OF THE NORTH HALF GETTING A LOT OF SUNSHINE BY THE MIDDLE OF THE DAY. COULD BE QUITE A GRADIENT WITH THE HIGH TEMPERATURES WITH THE NORTH THE WARMEST AS IT SEES THE MOST SUN. LINGERING SPOTTY PRECIPITATION SHOULD END BY LATE IN THE EVENING. DEPENDING ON HOW FAST IT CLEARS...TEMPERATURES COULD GET QUITE CHILLY WITH A VERY LIGHT WIND FIELD IN PLACE. TUESDAY/TUESDAY NIGHT...UPPER RIDGE AND NORTHERLY FLOW MOVE INTO THE AREA DURING THIS PERIOD. THIS SHOULD ALLOW FOR A DECENT AMOUNT OF SUN. ONE THING THAT COULD SPOIL THAT WILL BE A LEFT FRONT QUADRANT THAT MOVES IN AND SPREADS SOME CLOUDS INTO THE NORTHERN HALF OF THE AREA. ECMWF IS PRODUCING SOME LIGHT QPF. HOWEVER...THERE IS NO INSTABILITY AND A RATHER DEEP DRY LAYER. SO IT SHOULD STAY DRY. TEMPERATURES SHOULD WARM DUE TO SUNSHINE BUT WILL BE TEMPERED BY THE UNFAVORABLE SURFACE WIND FIELD. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 419 AM MDT SUN APR 26 2015 A RIDGE WILL CONTINUE BUILDING INTO THE PLAINS ON WEDNESDAY AS ANOTHER SYSTEM MOVES IN OVER THE PACIFIC NORTHWEST. DRY CONDITIONS ARE EXPECTED TO LAST THROUGH FRIDAY MORNING AS THE RIDGE PUSHES FURTHER EAST. PRECIP CHANCES MOVE INTO THE WESTERN CWA FRIDAY AFTERNOON AS THE PAC NW TROUGH MOVES INTO THE ROCKIES AND SWRLY UPPER LEVEL FLOW DEVELOPS. SLIGHT CHANCE OF PRECIP IS KEPT THROUGH THE END OF THE PERIOD FOR THE FORECAST AREA WITH SHORTWAVES POSSIBLY GENERATING SHOWERS AND THUNDERSTORMS AS THE TROUGH MOVES INTO THE PLAINS. WARMER TEMPERATURES ARE EXPECTED DURING THIS PERIOD WITH HIGHS IN THE 70S. READINGS IN THE LOW 80S ARE POSSIBLE BY THURSDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 550 AM MDT SUN APR 26 2015 FOR KGLD...LOW LEVEL AIR MASS WILL REMAIN VERY MOIST THROUGH THE PERIOD. AS A RESULT...LIFR TO IFR CEILINGS ARE EXPECTED THROUGH THE PERIOD. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE NEAR THE SITE THROUGH THE MORNING. HOWEVER...OCCASIONAL DRIZZLE...LIGHT RAIN OR FOG WILL PREVAIL ALMOST THE ENTIRE PERIOD. FOR KMCK...LOW LEVEL AIR MASS HERE WILL DRY WITH TIME. LIFR TO IFR CONDITIONS ARE EXPECTED UNTIL MID AFTERNOON WHEN MVFR CONDITIONS WILL BEGIN. MVFR CONDITIONS WILL THEN CONTINUE UNTIL 06Z. AT THAT TIME...VFR CONDITIONS ARE EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...BULLER LONG TERM...JBH AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
732 AM MDT SUN APR 26 2015 .UPDATE... ISSUED AT 732 AM MDT SUN APR 26 2015 UPDATE ISSUED TO ACCT FOR LATEST OBS TREND. CURRENTLY...THE ENTIRE TRI STATE REGION REMAINS UNDER A THICK VEIL OF LOW CLOUD...WITH TEMPS IN THE MID 40S. AREAS OF FOG PERSIST ALONG WITH DRIZZLE...SO PLAN ON KEEPING IN FORECAST FOR NOW AND WILL REVISIT FOR NEXT ESTF UPDATE. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 419 AM MDT SUN APR 26 2015 MAIN FORECAST CONCERNS WILL BE GRADIENT OF PRECIPITATION CHANCES INTO MONDAY AND HIGH TEMPERATURES TODAY/MONDAY. SATELLITE SHOWING THE FLOW HAS BECOME MORE AMPLIFIED FROM THE PACIFIC INTO THE WESTERN ATLANTIC OVER THE LAST 24 HOURS. SPLIT FLOW CONTINUES OVER THE WESTERN PORTION OF COUNTRY WITH EXPECTED SOUTHERN CUTOFF LOW NOW STARTING TO MOVE INTO ARIZONA/NEW MEXICO. NATURE OF FLOW WHICH IN SOME RESPECTS IS RETROGRESSING A LITTLE WOULD INDICATE THE PATTERN IS GOING TO BE SLOW TO CHANGE. COLD FRONT HAS MOVED THROUGH WITH UPSLOPE WINDS AND STRATUS ENTRENCHED ACROSS THE AREA. AT JET LEVEL...MODELS HANDLED THIS WELL THE GFS THE WORST AND TOO STRONG. AT MID LEVELS...MODELS WERE HAVING A LITTLE TROUBLE WITH THE DEVELOPING WESTERN TROUGH. THEY TENDED TO BE TOO DEEP WITH THE NAM THE WORST. OUTSIDE OF THIS THE NAM WAS NOT DOING TOO BAD. OVERALL THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND UKMET. THE CANADIAN WERE DOING THE WORST. MODELS HAD SURFACE LOW TO OUR SOUTHWEST TOO FAR NORTH. THE RUC AND ECMWF WERE DOING THE BEST. THE MODELS WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD WITH THE GFS...CANADIAN...SREF AND NAM DOING THE BEST. TODAY/TONIGHT...MAJORITY OF CONVECTION DURING THE EVENING STAYED MOSTLY TO THE WEST. UPSTREAM SOUNDINGS/UPPER AIR ANALYSIS TO THE SOUTH THROUGH THE WEST NOT PAINTING/SUPPORTING A WET FORECAST WITH A VERY DEEP DRY LAYER AND WHAT MOISTURE THERE IS AT 700 MB AT ITS LOWEST. IT LOOKS LIKE A LOT OF DRY AIR GETS PULLED INTO THE AREA BEFORE THE ARRIVAL OF ANY SIGNIFICANT DYNAMICS. UPPER AIR ANALYSIS SUPPORTS A RATHER FAR SOUTH SOLUTION OF THE EVENTUAL UPPER LOW WITH THE LARGEST HEIGHT FALLS OVER ARIZONA. NEW MODEL SUITE SUPPORTS WHAT THE ANALYSIS IS SHOWING. MAIN AREA OF PRECIPITATION HAS STAYED TO THE NORTH AND WEST OF THE AREA ALL NIGHT WITH ONLY A FEW RAIN SHOWERS ALONG WITH AREAS OF DRIZZLE AND FOG IN THE SATURATED LOW LEVELS. DYNAMICS TO OUR WEST BEGINS TO AFFECT MOST OF THE WESTERN TWO THIRDS OF THE FORECAST AREA THROUGH THE MIDDLE OF THE DAY BEFORE SOME DRYING ALOFT OCCUR AS THE LIFT MOVES AWAY FROM THE AREA. BASED ON THE LATEST MODEL DATA AND OBSERVATIONAL TRENDS...SHOULD HAVE A WIDE VARIETY OF WEATHER THIS MORNING. AREAS OF FOG AND DRIZZLE ALONG WITH SOME RAIN SHOWERS SHOULD PERSIST DURING THE MORNING. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT WITH ELEVATED CAPE AND FAVORABLE LAPSE RATES IN PLACE. WILL BE A LULL IN THE PRECIPITATION FOR MOST OF THE REST OF THE DAY. AS HAS BEEN THE CASE THE LAST FEW DAYS...THE FAR WEST AND SOUTHWEST WILL HAVE THE BEST CHANCE OF PRECIPITATION DURING THIS TIME. CLOUD COVER SHOULD STAY THICK MOST OF THE DAY WITH MAYBE SOME CLEARING IN THE FAR EASTERN PORTION AS A LITTLE DRIER AIR MOVES IN TO THERE. KEPT THE COOLER TEMPERATURES IN PLACE WITH COOLEST READINGS IN THE FAR WEST WHERE TEMPERATURES MAY NEED NOT GET OUT OF THE 40S. SOUTHERN CUTOFF LOW GETS ORGANIZED AND IN A DECENT POSITION TO GIVE THE AREA SOME LIGHT PRECIPITATION LATER THIS AFTERNOON INTO TONIGHT...ESPECIALLY IN THE SOUTHWEST THIRD TO HALF. THE BEST CHANCE OF PRECIPITATION LOOKS TO OCCUR FROM EARLY EVENING TO NEAR 09Z AS THE BEST/DEEPEST MOISTURE GETS IN PLACE. AFTER THAT THE MOISTURE AND PRECIPITATION STARTS ITS GRADUAL SLIDE TO THE SOUTH AND EAST. MONDAY/MONDAY NIGHT...UPPER SYSTEM AND ASSOCIATED MOISTURE AND PRECIPITATION CONTINUES ITS SHIFT SOUTH AND EAST AS THE EXITING SYSTEM MOVES AWAY. ONCE AGAIN THE FAR SOUTH AND SOUTHWEST WILL HAVE THE BEST CHANCE FOR LIGHT PRECIPITATION. CLEARING WILL ALSO BEGIN WITH MOST OF THE NORTH HALF GETTING A LOT OF SUNSHINE BY THE MIDDLE OF THE DAY. COULD BE QUITE A GRADIENT WITH THE HIGH TEMPERATURES WITH THE NORTH THE WARMEST AS IT SEES THE MOST SUN. LINGERING SPOTTY PRECIPITATION SHOULD END BY LATE IN THE EVENING. DEPENDING ON HOW FAST IT CLEARS...TEMPERATURES COULD GET QUITE CHILLY WITH A VERY LIGHT WIND FIELD IN PLACE. TUESDAY/TUESDAY NIGHT...UPPER RIDGE AND NORTHERLY FLOW MOVE INTO THE AREA DURING THIS PERIOD. THIS SHOULD ALLOW FOR A DECENT AMOUNT OF SUN. ONE THING THAT COULD SPOIL THAT WILL BE A LEFT FRONT QUADRANT THAT MOVES IN AND SPREADS SOME CLOUDS INTO THE NORTHERN HALF OF THE AREA. ECMWF IS PRODUCING SOME LIGHT QPF. HOWEVER...THERE IS NO INSTABILITY AND A RATHER DEEP DRY LAYER. SO IT SHOULD STAY DRY. TEMPERATURES SHOULD WARM DUE TO SUNSHINE BUT WILL BE TEMPERED BY THE UNFAVORABLE SURFACE WIND FIELD. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 419 AM MDT SUN APR 26 2015 A RIDGE WILL CONTINUE BUILDING INTO THE PLAINS ON WEDNESDAY AS ANOTHER SYSTEM MOVES IN OVER THE PACIFIC NORTHWEST. DRY CONDITIONS ARE EXPECTED TO LAST THROUGH FRIDAY MORNING AS THE RIDGE PUSHES FURTHER EAST. PRECIP CHANCES MOVE INTO THE WESTERN CWA FRIDAY AFTERNOON AS THE PAC NW TROUGH MOVES INTO THE ROCKIES AND SWRLY UPPER LEVEL FLOW DEVELOPS. SLIGHT CHANCE OF PRECIP IS KEPT THROUGH THE END OF THE PERIOD FOR THE FORECAST AREA WITH SHORTWAVES POSSIBLY GENERATING SHOWERS AND THUNDERSTORMS AS THE TROUGH MOVES INTO THE PLAINS. WARMER TEMPERATURES ARE EXPECTED DURING THIS PERIOD WITH HIGHS IN THE 70S. READINGS IN THE LOW 80S ARE POSSIBLE BY THURSDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 550 AM MDT SUN APR 26 2015 FOR KGLD...LOW LEVEL AIR MASS WILL REMAIN VERY MOIST THROUGH THE PERIOD. AS A RESULT...LIFR TO IFR CEILINGS ARE EXPECTED THROUGH THE PERIOD. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE NEAR THE SITE THROUGH THE MORNING. HOWEVER...OCCASIONAL DRIZZLE...LIGHT RAIN OR FOG WILL PREVAIL ALMOST THE ENTIRE PERIOD. FOR KMCK...LOW LEVEL AIR MASS HERE WILL DRY WITH TIME. LIFR TO IFR CONDITIONS ARE EXPECTED UNTIL MID AFTERNOON WHEN MVFR CONDITIONS WILL BEGIN. MVFR CONDITIONS WILL THEN CONTINUE UNTIL 06Z. AT THAT TIME...VFR CONDITIONS ARE EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...BULLER LONG TERM...JBH AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
556 AM MDT SUN APR 26 2015 .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 419 AM MDT SUN APR 26 2015 MAIN FORECAST CONCERNS WILL BE GRADIENT OF PRECIPITATION CHANCES INTO MONDAY AND HIGH TEMPERATURES TODAY/MONDAY. SATELLITE SHOWING THE FLOW HAS BECOME MORE AMPLIFIED FROM THE PACIFIC INTO THE WESTERN ATLANTIC OVER THE LAST 24 HOURS. SPLIT FLOW CONTINUES OVER THE WESTERN PORTION OF COUNTRY WITH EXPECTED SOUTHERN CUTOFF LOW NOW STARTING TO MOVE INTO ARIZONA/NEW MEXICO. NATURE OF FLOW WHICH IN SOME RESPECTS IS RETROGRESSING A LITTLE WOULD INDICATE THE PATTERN IS GOING TO BE SLOW TO CHANGE. COLD FRONT HAS MOVED THROUGH WITH UPSLOPE WINDS AND STRATUS ENTRENCHED ACROSS THE AREA. AT JET LEVEL...MODELS HANDLED THIS WELL THE GFS THE WORST AND TOO STRONG. AT MID LEVELS...MODELS WERE HAVING A LITTLE TROUBLE WITH THE DEVELOPING WESTERN TROUGH. THEY TENDED TO BE TOO DEEP WITH THE NAM THE WORST. OUTSIDE OF THIS THE NAM WAS NOT DOING TOO BAD. OVERALL THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND UKMET. THE CANADIAN WERE DOING THE WORST. MODELS HAD SURFACE LOW TO OUR SOUTHWEST TOO FAR NORTH. THE RUC AND ECMWF WERE DOING THE BEST. THE MODELS WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD WITH THE GFS...CANADIAN...SREF AND NAM DOING THE BEST. TODAY/TONIGHT...MAJORITY OF CONVECTION DURING THE EVENING STAYED MOSTLY TO THE WEST. UPSTREAM SOUNDINGS/UPPER AIR ANALYSIS TO THE SOUTH THROUGH THE WEST NOT PAINTING/SUPPORTING A WET FORECAST WITH A VERY DEEP DRY LAYER AND WHAT MOISTURE THERE IS AT 700 MB AT ITS LOWEST. IT LOOKS LIKE A LOT OF DRY AIR GETS PULLED INTO THE AREA BEFORE THE ARRIVAL OF ANY SIGNIFICANT DYNAMICS. UPPER AIR ANALYSIS SUPPORTS A RATHER FAR SOUTH SOLUTION OF THE EVENTUAL UPPER LOW WITH THE LARGEST HEIGHT FALLS OVER ARIZONA. NEW MODEL SUITE SUPPORTS WHAT THE ANALYSIS IS SHOWING. MAIN AREA OF PRECIPITATION HAS STAYED TO THE NORTH AND WEST OF THE AREA ALL NIGHT WITH ONLY A FEW RAIN SHOWERS ALONG WITH AREAS OF DRIZZLE AND FOG IN THE SATURATED LOW LEVELS. DYNAMICS TO OUR WEST BEGINS TO AFFECT MOST OF THE WESTERN TWO THIRDS OF THE FORECAST AREA THROUGH THE MIDDLE OF THE DAY BEFORE SOME DRYING ALOFT OCCUR AS THE LIFT MOVES AWAY FROM THE AREA. BASED ON THE LATEST MODEL DATA AND OBSERVATIONAL TRENDS...SHOULD HAVE A WIDE VARIETY OF WEATHER THIS MORNING. AREAS OF FOG AND DRIZZLE ALONG WITH SOME RAIN SHOWERS SHOULD PERSIST DURING THE MORNING. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT WITH ELEVATED CAPE AND FAVORABLE LAPSE RATES IN PLACE. WILL BE A LULL IN THE PRECIPITATION FOR MOST OF THE REST OF THE DAY. AS HAS BEEN THE CASE THE LAST FEW DAYS...THE FAR WEST AND SOUTHWEST WILL HAVE THE BEST CHANCE OF PRECIPITATION DURING THIS TIME. CLOUD COVER SHOULD STAY THICK MOST OF THE DAY WITH MAYBE SOME CLEARING IN THE FAR EASTERN PORTION AS A LITTLE DRIER AIR MOVES IN TO THERE. KEPT THE COOLER TEMPERATURES IN PLACE WITH COOLEST READINGS IN THE FAR WEST WHERE TEMPERATURES MAY NEED NOT GET OUT OF THE 40S. SOUTHERN CUTOFF LOW GETS ORGANIZED AND IN A DECENT POSITION TO GIVE THE AREA SOME LIGHT PRECIPITATION LATER THIS AFTERNOON INTO TONIGHT...ESPECIALLY IN THE SOUTHWEST THIRD TO HALF. THE BEST CHANCE OF PRECIPITATION LOOKS TO OCCUR FROM EARLY EVENING TO NEAR 09Z AS THE BEST/DEEPEST MOISTURE GETS IN PLACE. AFTER THAT THE MOISTURE AND PRECIPITATION STARTS ITS GRADUAL SLIDE TO THE SOUTH AND EAST. MONDAY/MONDAY NIGHT...UPPER SYSTEM AND ASSOCIATED MOISTURE AND PRECIPITATION CONTINUES ITS SHIFT SOUTH AND EAST AS THE EXITING SYSTEM MOVES AWAY. ONCE AGAIN THE FAR SOUTH AND SOUTHWEST WILL HAVE THE BEST CHANCE FOR LIGHT PRECIPITATION. CLEARING WILL ALSO BEGIN WITH MOST OF THE NORTH HALF GETTING A LOT OF SUNSHINE BY THE MIDDLE OF THE DAY. COULD BE QUITE A GRADIENT WITH THE HIGH TEMPERATURES WITH THE NORTH THE WARMEST AS IT SEES THE MOST SUN. LINGERING SPOTTY PRECIPITATION SHOULD END BY LATE IN THE EVENING. DEPENDING ON HOW FAST IT CLEARS...TEMPERATURES COULD GET QUITE CHILLY WITH A VERY LIGHT WIND FIELD IN PLACE. TUESDAY/TUESDAY NIGHT...UPPER RIDGE AND NORTHERLY FLOW MOVE INTO THE AREA DURING THIS PERIOD. THIS SHOULD ALLOW FOR A DECENT AMOUNT OF SUN. ONE THING THAT COULD SPOIL THAT WILL BE A LEFT FRONT QUADRANT THAT MOVES IN AND SPREADS SOME CLOUDS INTO THE NORTHERN HALF OF THE AREA. ECMWF IS PRODUCING SOME LIGHT QPF. HOWEVER...THERE IS NO INSTABILITY AND A RATHER DEEP DRY LAYER. SO IT SHOULD STAY DRY. TEMPERATURES SHOULD WARM DUE TO SUNSHINE BUT WILL BE TEMPERED BY THE UNFAVORABLE SURFACE WIND FIELD. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 419 AM MDT SUN APR 26 2015 A RIDGE WILL CONTINUE BUILDING INTO THE PLAINS ON WEDNESDAY AS ANOTHER SYSTEM MOVES IN OVER THE PACIFIC NORTHWEST. DRY CONDITIONS ARE EXPECTED TO LAST THROUGH FRIDAY MORNING AS THE RIDGE PUSHES FURTHER EAST. PRECIP CHANCES MOVE INTO THE WESTERN CWA FRIDAY AFTERNOON AS THE PAC NW TROUGH MOVES INTO THE ROCKIES AND SWRLY UPPER LEVEL FLOW DEVELOPS. SLIGHT CHANCE OF PRECIP IS KEPT THROUGH THE END OF THE PERIOD FOR THE FORECAST AREA WITH SHORTWAVES POSSIBLY GENERATING SHOWERS AND THUNDERSTORMS AS THE TROUGH MOVES INTO THE PLAINS. WARMER TEMPERATURES ARE EXPECTED DURING THIS PERIOD WITH HIGHS IN THE 70S. READINGS IN THE LOW 80S ARE POSSIBLE BY THURSDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 550 AM MDT SUN APR 26 2015 FOR KGLD...LOW LEVEL AIR MASS WILL REMAIN VERY MOIST THROUGH THE PERIOD. AS A RESULT...LIFR TO IFR CEILINGS ARE EXPECTED THROUGH THE PERIOD. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE NEAR THE SITE THROUGH THE MORNING. HOWEVER...OCCASIONAL DRIZZLE...LIGHT RAIN OR FOG WILL PREVAIL ALMOST THE ENTIRE PERIOD. FOR KMCK...LOW LEVEL AIR MASS HERE WILL DRY WITH TIME. LIFR TO IFR CONDITIONS ARE EXPECTED UNTIL MID AFTERNOON WHEN MVFR CONDITIONS WILL BEGIN. MVFR CONDITIONS WILL THEN CONTINUE UNTIL 06Z. AT THAT TIME...VFR CONDITIONS ARE EXPECTED. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...JBH AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
420 AM MDT SUN APR 26 2015 .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 419 AM MDT SUN APR 26 2015 MAIN FORECAST CONCERNS WILL BE GRADIENT OF PRECIPITATION CHANCES INTO MONDAY AND HIGH TEMPERATURES TODAY/MONDAY. SATELLITE SHOWING THE FLOW HAS BECOME MORE AMPLIFIED FROM THE PACIFIC INTO THE WESTERN ATLANTIC OVER THE LAST 24 HOURS. SPLIT FLOW CONTINUES OVER THE WESTERN PORTION OF COUNTRY WITH EXPECTED SOUTHERN CUTOFF LOW NOW STARTING TO MOVE INTO ARIZONA/NEW MEXICO. NATURE OF FLOW WHICH IN SOME RESPECTS IS RETROGRESSING A LITTLE WOULD INDICATE THE PATTERN IS GOING TO BE SLOW TO CHANGE. COLD FRONT HAS MOVED THROUGH WITH UPSLOPE WINDS AND STRATUS ENTRENCHED ACROSS THE AREA. AT JET LEVEL...MODELS HANDLED THIS WELL THE GFS THE WORST AND TOO STRONG. AT MID LEVELS...MODELS WERE HAVING A LITTLE TROUBLE WITH THE DEVELOPING WESTERN TROUGH. THEY TENDED TO BE TOO DEEP WITH THE NAM THE WORST. OUTSIDE OF THIS THE NAM WAS NOT DOING TOO BAD. OVERALL THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND UKMET. THE CANADIAN WERE DOING THE WORST. MODELS HAD SURFACE LOW TO OUR SOUTHWEST TOO FAR NORTH. THE RUC AND ECMWF WERE DOING THE BEST. THE MODELS WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD WITH THE GFS...CANADIAN...SREF AND NAM DOING THE BEST. TODAY/TONIGHT...MAJORITY OF CONVECTION DURING THE EVENING STAYED MOSTLY TO THE WEST. UPSTREAM SOUNDINGS/UPPER AIR ANALYSIS TO THE SOUTH THROUGH THE WEST NOT PAINTING/SUPPORTING A WET FORECAST WITH A VERY DEEP DRY LAYER AND WHAT MOISTURE THERE IS AT 700 MB AT ITS LOWEST. IT LOOKS LIKE A LOT OF DRY AIR GETS PULLED INTO THE AREA BEFORE THE ARRIVAL OF ANY SIGNIFICANT DYNAMICS. UPPER AIR ANALYSIS SUPPORTS A RATHER FAR SOUTH SOLUTION OF THE EVENTUAL UPPER LOW WITH THE LARGEST HEIGHT FALLS OVER ARIZONA. NEW MODEL SUITE SUPPORTS WHAT THE ANALYSIS IS SHOWING. MAIN AREA OF PRECIPITATION HAS STAYED TO THE NORTH AND WEST OF THE AREA ALL NIGHT WITH ONLY A FEW RAIN SHOWERS ALONG WITH AREAS OF DRIZZLE AND FOG IN THE SATURATED LOW LEVELS. DYNAMICS TO OUR WEST BEGINS TO AFFECT MOST OF THE WESTERN TWO THIRDS OF THE FORECAST AREA THROUGH THE MIDDLE OF THE DAY BEFORE SOME DRYING ALOFT OCCUR AS THE LIFT MOVES AWAY FROM THE AREA. BASED ON THE LATEST MODEL DATA AND OBSERVATIONAL TRENDS...SHOULD HAVE A WIDE VARIETY OF WEATHER THIS MORNING. AREAS OF FOG AND DRIZZLE ALONG WITH SOME RAIN SHOWERS SHOULD PERSIST DURING THE MORNING. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT WITH ELEVATED CAPE AND FAVORABLE LAPSE RATES IN PLACE. WILL BE A LULL IN THE PRECIPITATION FOR MOST OF THE REST OF THE DAY. AS HAS BEEN THE CASE THE LAST FEW DAYS...THE FAR WEST AND SOUTHWEST WILL HAVE THE BEST CHANCE OF PRECIPITATION DURING THIS TIME. CLOUD COVER SHOULD STAY THICK MOST OF THE DAY WITH MAYBE SOME CLEARING IN THE FAR EASTERN PORTION AS A LITTLE DRIER AIR MOVES IN TO THERE. KEPT THE COOLER TEMPERATURES IN PLACE WITH COOLEST READINGS IN THE FAR WEST WHERE TEMPERATURES MAY NEED NOT GET OUT OF THE 40S. SOUTHERN CUTOFF LOW GETS ORGANIZED AND IN A DECENT POSITION TO GIVE THE AREA SOME LIGHT PRECIPITATION LATER THIS AFTERNOON INTO TONIGHT...ESPECIALLY IN THE SOUTHWEST THIRD TO HALF. THE BEST CHANCE OF PRECIPITATION LOOKS TO OCCUR FROM EARLY EVENING TO NEAR 09Z AS THE BEST/DEEPEST MOISTURE GETS IN PLACE. AFTER THAT THE MOISTURE AND PRECIPITATION STARTS ITS GRADUAL SLIDE TO THE SOUTH AND EAST. MONDAY/MONDAY NIGHT...UPPER SYSTEM AND ASSOCIATED MOISTURE AND PRECIPITATION CONTINUES ITS SHIFT SOUTH AND EAST AS THE EXITING SYSTEM MOVES AWAY. ONCE AGAIN THE FAR SOUTH AND SOUTHWEST WILL HAVE THE BEST CHANCE FOR LIGHT PRECIPITATION. CLEARING WILL ALSO BEGIN WITH MOST OF THE NORTH HALF GETTING A LOT OF SUNSHINE BY THE MIDDLE OF THE DAY. COULD BE QUITE A GRADIENT WITH THE HIGH TEMPERATURES WITH THE NORTH THE WARMEST AS IT SEES THE MOST SUN. LINGERING SPOTTY PRECIPITATION SHOULD END BY LATE IN THE EVENING. DEPENDING ON HOW FAST IT CLEARS...TEMPERATURES COULD GET QUITE CHILLY WITH A VERY LIGHT WIND FIELD IN PLACE. TUESDAY/TUESDAY NIGHT...UPPER RIDGE AND NORTHERLY FLOW MOVE INTO THE AREA DURING THIS PERIOD. THIS SHOULD ALLOW FOR A DECENT AMOUNT OF SUN. ONE THING THAT COULD SPOIL THAT WILL BE A LEFT FRONT QUADRANT THAT MOVES IN AND SPREADS SOME CLOUDS INTO THE NORTHERN HALF OF THE AREA. ECMWF IS PRODUCING SOME LIGHT QPF. HOWEVER...THERE IS NO INSTABILITY AND A RATHER DEEP DRY LAYER. SO IT SHOULD STAY DRY. TEMPERATURES SHOULD WARM DUE TO SUNSHINE BUT WILL BE TEMPERED BY THE UNFAVORABLE SURFACE WIND FIELD. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 419 AM MDT SUN APR 26 2015 A RIDGE WILL CONTINUE BUILDING INTO THE PLAINS ON WEDNESDAY AS ANOTHER SYSTEM MOVES IN OVER THE PACIFIC NORTHWEST. DRY CONDITIONS ARE EXPECTED TO LAST THROUGH FRIDAY MORNING AS THE RIDGE PUSHES FURTHER EAST. PRECIP CHANCES MOVE INTO THE WESTERN CWA FRIDAY AFTERNOON AS THE PAC NW TROUGH MOVES INTO THE ROCKIES AND SWRLY UPPER LEVEL FLOW DEVELOPS. SLIGHT CHANCE OF PRECIP IS KEPT THROUGH THE END OF THE PERIOD FOR THE FORECAST AREA WITH SHORTWAVES POSSIBLY GENERATING SHOWERS AND THUNDERSTORMS AS THE TROUGH MOVES INTO THE PLAINS. WARMER TEMPERATURES ARE EXPECTED DURING THIS PERIOD WITH HIGHS IN THE 70S. READINGS IN THE LOW 80S ARE POSSIBLE BY THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1030 PM MDT SAT APR 25 2015 KGLD...IFR/VLIFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH THE FORECAST PERIOD. WINDS GENERALLY FROM THE EAST GUSTING 15 TO 20KTS AT TIMES. THERE IS A CHANCE FOR ELEVATED THUNDERSTORMS TO BE IN THE VICINITY OR OVER THE TERMINAL FROM 08Z-20Z AS VARIOUS WEATHER DISTURBANCES MOVE OVER THE AREA FROM THE SOUTHWEST. KMCK...IFR/VLIFR CONDITIONS EXPECTED FROM TAF ISSUANCE THROUGH 19Z WITH EAST WINDS OCCASIONALLY GUSTING 15-20KTS. FROM 20Z-01Z CIGS IMPROVE SLIGHTLY TO MVFR CATEGORY WITH CONTINUED EAST WIND GUSTING TO 20KTS. AFTER 02Z CIGS LOOK TO RISE JUST ABOVE MVFR CATEGORY WITH WINDS VERY SLOWLY DECREASING TOWARD 10KTS...ESPECIALLY AT THE END OF THE FORECAST PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...JBH AVIATION...99
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
711 AM EDT SUN APR 26 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT SUN APR 26 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW MID LEVEL RIDGE EXTENDING FROM THE NRN PLAINS TO SRN HUDSON BAY. TO THE SE...A MID LEVEL LOW IS CENTERED OFF THE CANADIAN MARITIMES WITH ITS BROAD CIRCULATION EXTENDING BACK TO THE UPPER LAKES. TWO SHORTWAVES OF NOTE ARE SWINGING W IN THE MID LEVEL LOW CIRCULATION ACROSS SE CANADA. THE FIRST IS S OF JAMES BAY AND THE SECOND IS N OF MAINE. AT THE SFC... THE MID LEVEL RIDGE IS SUPPORTING HIGH PRES RIDGING S FROM HUDSON BAY INTO THE UPPER MISSISSIPPI VALLEY. UNDER DRY AIR MASS PER 00Z REGIONAL SOUNDINGS...CLEAR SKIES CONTINUE TO PREVAIL ACROSS THE FCST AREA EARLY THIS MORNING. TO THE NE...FIRST SHORTWAVE S OF JAMES IS HELPING TO SPREAD SCT-BKN CLOUDS TOWARD LAKE SUPERIOR. THE FIRST SHORTWAVE S OF JAMES BAY WILL ROTATE INTO NRN LWR MI THIS AFTN/EVENING...SPREADING SOME CLOUDINESS INTO THE ERN FCST AREA TODAY. TRENDS IN THE MODELS SHOW A BACKING OFF ON THE POTENTIAL CLOUD COVER WHICH SEEMS REASONABLE BASED ON OVERNIGHT SATELLITE IMAGERY. FCST THUS REFLECTS A MORE OPTIMISTIC SKY CONDITION FOR CNTRL UPPER MI TODAY. MAY STILL SEE SOME PERIODS OF MOSTLY CLOUDY CONDITIONS OVER THE ERN FCST AREA THIS AFTN...ESPECIALLY LATE. AS FOR TEMPS...RATHER BRISK GRADIENT FLOW OFF LAKE SUPERIOR WILL HOLD TEMPS TO THE LOWER 40S NEAR LAKE SUPERIOR TODAY. MOST LAKESIDE LOCATIONS FROM THE KEWEENAW EASTWARD WILL NOT GET OUT OF THE 30S. WELL INLAND...NAM/GFS FCST SOUNDINGS AND PROJECTED MIXING HEIGHTS SUGGEST HIGH TEMPS MAY STRUGGLE TO REACH 50F. THERE MAY BE SOME LWR 50S TOWARD THE MI/WI BORDER FROM MENOMINEE COUNTY TO IRON COUNTY. TONIGHT...SECOND SHORTWAVE NOW N OF MAINE WILL FOLLOW THE SAME TRACK AS THE FIRST AND SHOULD REACH NRN LWR MI LATE TONIGHT. MODELS ARE AGGRESSIVE IN SWINGING MOISTURE BACK INTO UPPER MI TONIGHT WITH THIS FEATURE. OF PARTICULAR NOTE IS THE LOW-LEVEL MOISTURE THE NAM/GFS SHOW. LOOKING TO THE NE...LOW CIGS ARE NOTED IN AND AROUND JAMES BAY AND EASTWARD EARLY THIS MORNING. WITH THIS MOISTURE PUSHING SW INTO THE AREA DURING THE NIGHT WHEN DAYTIME HEATING IS ABSENT TO HELP LIFT OR MIX MOISTURE OUT...IT LOOKS FAIRLY LIKELY THAT LOW CLOUDS WILL DEVELOP/EXPAND TONIGHT...ESPECIALLY LATE...OVER AT LEAST THE NCNTRL AND E...AIDED BY UPSLOPE FLOW. NAM FCST SOUNDINGS EVEN SUGGEST THE POTENTIAL FOR SOME -DZ/-FZDZ WHERE STRONGEST UPSLOPE OCCURS. WILL BE SOMETHING TO TAKE A LOOK AT AGAIN IN LATER MODEL RUNS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 400 AM EDT SUN APR 26 2015 LINGERING LOW LEVEL MOISTURE AND COOLER AIRMASS BEHIND A SHORTWAVE TROUGH THAT MOVED THROUGH SUN NIGHT WILL LEAD TO CLOUD COVER EARLY MON OVER ESPECIALLY THE CENTRAL AND ERN CWA. THE CLOUD COVER WILL SLOWLY DIMINISH AS THE SFC RIDGE MOVES BACK IN FROM THE W AS WELL AS THE APPROACH OF AN UPPER RIDGE. CAN NOT COMPLETELY RULE OUT SOME LIGHT DRIZZLE IN UPSLOPE AREAS OF NCENTRAL UPPER MI...BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN THE FORECAST. INTERIOR W SHOULD SEE HIGHS APPROACH 60F ON MON...WHILE LAKESHORE AND ERN AREAS ARE QUITE A BIT COOLER WITH HIGHS IN THE UPPER 30S TO THE UPPER 40S. A COUPLE OF ROUNDS OF SHORTWAVE ENERGY WILL BREAK DOWN THE RIDGE TUE EVENING AND AGAIN ON WED...WITH MODELS CURRENTLY SHOWING THE STRONGER SHORTWAVE ON WED. MODELS HAVE NOT SHOWN GOOD CONTINUITY WITH THESE FEATURES...SO CONFIDENCE IN EXACT DETAILS IS LOW. HOWEVER...MODEL DO GENERALLY AGREE THAT MOISTURE WILL BE LIMITED ENOUGH TO KEEP ANY SIGNIFICANT PRECIP FROM OCCURING. TUE WILL BE WARMER THAN MON WITH HIGHS IN THE 50S AND 60S AS THE AIRMASS WILL BE WARMER AND THE SHORTWAVE/CLOUD COVER DOES NOT ARRIVE UNTIL LATER IN THE DAY. WED COULD SEE A SIGNIFICANT COOLER AIRMASS DEPENDING ON DETAILS WITH THE SHORTWAVE...POSSIBLY RESULTING IN HIGH TEMPS IN THE 40S TO MID 50S. UPPER RIDGING REPLACES THE SHORTWAVE ENERGY THU INTO FRI. MODELS HAVE BEEN STRUGGLING WITH CONTINUITY IN THE STRENGTH OF THE RIDGE...LIMITED CONFIDENCE SOME. HIGHS ON THU WILL BE IN THE 50S TO MID 60S...WITH SIGNIFICANTLY WARMER HIGHS IN THE 60S TO LOW 70S ON FRI. MODEL DISAGREEMENT AND DISCONTINUITY CERTAINLY CONTINUE AND INCREASE ON SAT AS MODELS VARY VASTLY IN THE STRENGTH AND PLACEMENT OF UPPER LEVEL ENERGY OVER CENTRAL CANADA. MODELS SHOW SOME SHORTWAVE ENERGY MOVING ACROSS THE CWA WITH A WEAK SFC TROUGH LATE FRI AND FRI NIGHT...WHICH COULD PRODUCE CONVECTION ACROSS THE CWA. WILL CONTINUE SHOWING SLIGHT CHANCE POPS GIVEN UNCERTAINTY. ADDITIONAL DIFFERENCE BETWEEN MODELS /ALSO TIED TO UNCERTAINTIES WITH THE CENTRAL CANADA ENERGY/ WITH TEMPS ON SAT. THE 12Z/25 ECMWF BRINGS AN AMPLIFIED UPPER RIDGE TO JUST W OF THE CWA BY 00Z SUN WHILE THE 00Z/26 GFS HAS AN UPPER TROUGH WHERE THE ECMWF HAS THE RIDGE. AIRMASS WILL BE A LOT WARMER UNDER THE ECMWF SOLUTION WITH 850MB TEMPS OF 12C BY 00Z SUN WHILE THE GFS IS AT 8C. WHILE POTENTIAL FOR MUCH WARMER TEMPS EXISTS...CONFIDENCE IS LOW SO WILL CONTINUE WITH A CONSENSUS APPROACH WITH HIGHS INT HE 60S AND 70S AWAY FROM THE IMMEDIATE LAKESHORE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 710 AM EDT SUN APR 26 2015 FCST CHALLENGE DURING THIS FCST PERIOD WILL BE THE SOUTHWESTWARD PUSH OF MOISTURE/LOW CLOUDS THAT ARE CURRENTLY NE OF LAKE SUPERIOR. INITIALLY TODAY INTO THE EVENING HOURS...EXPECT DAYTIME HEATING TO HELP MIX OUT LOW-LEVEL MOISTURE STREAMING TOWARD THE AREA... RESULTING IN PREVAILING VFR CONDITIONS AT KIWD/KCMX/KSAW. TONIGHT...LOW CLOUDS SHOULD MAKE A STRONG PUSH INTO THE AREA. KSAW IS MOST LIKELY TO BE AFFECTED. AIDED BY UPSLOPE FLOW...EXPECT CIGS TO FALL TO IFR THERE DURING THE OVERNIGHT. NOT OUT OF THE QUESTION THAT CIGS COULD EVEN FALL TO LIFR. KCMX SHOULD SEE LOW MVFR CIGS... POSSIBLY IFR...DEVELOP OVERNIGHT. FARTHEST W FROM THE MOISTURE SURGE...KIWD MAY STAY VFR TONIGHT...BUT AN IFR CIG IS A POSSIBILITY LATE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 507 AM EDT SUN APR 26 2015 WITH SFC HIGH PRES RIDGING S THRU WRN LAKE SUPERIOR TODAY THRU MON...WINDS WILL BE LIGHTEST OVER WRN LAKE SUPERIOR...MOSTLY UNDER 15KT. OVER THE E...WINDS WILL OCCASIONALLY GUST TO 20-25KT. THE RIDGE WILL WEAKEN TUE AND GIVE WAY TO LOW PRES TROF PASSAGE TUE NIGHT. IN ITS WAKE...ANOTHER HIGH PRES WILL RIDGE S FROM HUDSON BAY INTO THE UPPER GREAT LAKES WED/THU. WITH PRES GRADIENT ON THE WEAK SIDE...WINDS TUE THRU THU SHOULD BE UNDER 15KT ACROSS LAKE SUPERIOR THOUGH THERE MAY BE SOME STRONGER WINDS ON WED AS THE HIGH BEGINS RIDGING S INTO THE UPPER LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
630 AM CDT SUN APR 26 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CDT SUN APR 26 2015 A VERY PLEASANT DAY IS AHEAD WITH A RIDGE OF HIGH PRESSURE HOLDING STEADY FROM WESTERN ONTARIO THROUGH MINNESOTA AND WISCONSIN. THE SKY WILL BE MAINLY CLEAR TODAY AS WELL AS TONIGHT ALONG WITH A LIGHT NORTHEAST TO EAST WIND. HIGHS THIS AFTERNOON WILL BE SIMILAR THOSE ON SATURDAY WITH LOWER TO MIDDLE 60S FORECAST...WHICH IS VERY CLOSE TO THE SEASONAL NORMAL. THE FORECAST HIGHS TODAY LINE UP WELL WITH MIX-DOWN FROM THE NAM AT 825MB ALONG WITH A SLIGHT SUPER. THE REAL CHALLENGE TODAY IS HOW LOW WILL DEW POINTS DROP... ESPECIALLY ACROSS CENTRAL MN...AND THE CORRESPONDING AFTERNOON MINIMUM HUMIDITY. THE LOW LEVEL NORTHEAST FLOW BROUGHT DEW POINTS IN THE SINGLE DIGITS AND LOWER TEENS INTO NORTHEAST MN SATURDAY EVENING. DEW POINTS NEAR 20 DEGREES ARE NOW PREVALENT ACROSS CENTRAL MN EARLY THIS MORNING. THE NAM AND RAP HAVE A GOOD HANDLE ON THE SITUATION AND LOWER DEW POINTS TO NEAR 15 DEGREES ACROSS MUCH OF CENTRAL MN THIS AFTERNOON WITH AROUND 20 HERE IN THE TWIN CITIES AND WEST CENTRAL WI. THIS RESULTS IN NEAR 15 PERCENT MINIMUM HUMIDITY THIS AFTERNOON ACROSS MUCH OF CENTRAL MN WITH 20 PERCENT HERE IN THE CITIES AND WEST CENTRAL WI. SOUTHERN AREAS OF MN BOTTOM OUT AROUND 25 PERCENT. FORTUNATELY...THE NORTHEAST TO EAST WINDS ARE EXPECTED TO STAY AT OR BELOW 10 MPH THIS AFTERNOON KEEPING THE FIRE THREAT MAINLY IN THE LIMITED RANGE WITH ELEVATED INDICATED ACROSS WEST CENTRAL MINNESOTA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 349 AM CDT SUN APR 26 2015 MILD TEMPERATURES STILL LOOK ON TAP FOR NEXT WEEK...WITH TWO MOISTURE STARVED FRONTS TRAVERSING THE UPPER MS RIVER VALLEY MONDAY NIGHT/TUESDAY AND AGAIN ON FRIDAY. THE TROUBLE MAKER FOR MODEL AGREEMENT THROUGH THE EXTENDED CONTINUES TO BE THE EVOLUTION OF THE DEEP CLOSED H5 LOW OVER NEW ENGLAND NEXT WEEK. MODEL AGREEMENT IS NOT REALLY ALL THAT BAD UNTIL WE GET TO THURSDAY...WHEN THE GFS STARTS TO BECOME MORE AGGRESSIVE WITH PUSHING THIS LOW OUT INTO THE NORTH ATLANTIC...WHICH ALLOWS IT TO BECOME CONSIDERABLY MORE PROGRESSIVE THAN THE GEM/ECMWF WITH THE FLOW ACROSS THE CONUS TO END THE WORK WORK GOING INTO NEXT WEEKEND. FOR MODEL PREFERENCES...WENT WITH A FAIRLY EQUAL BLEND THROUGH THURSDAY...LEANING MORE TOWARD THE LESS PROGRESSIVE ECMWF SOLUTION FOR FRIDAY INTO NEXT WEEKEND. THE LONG TERM WILL START OFF WITH A PICTURE PERFECT DAY ON MONDAY...WITH HIGHS IN THE UPPER 60S/LOWER 70S...SUNNY SKIES AND LIGHT WINDS. MONDAY NIGHT WILL FEATURE A SHORTWAVE MOVING INTO NORTHERN MN...WITH A WEAK COLD FRONT MOVING INTO THE AREA AS WELL. PRECIP POTENTIAL STILL DOES NOT LOOK ALL THAT GREAT FOR THIS FRONT...WITH THE UPPER LOW OVER TEXAS KEEPING ANY MEANINGFUL MOISTURE WELL OF TO OUR SOUTH...WITH CONVERGENCE ALONG THE BOUNDARY LOOKING WEAK AS WELL. THE ECMWF CONTINUES TO BE AN OUTLIER WITH THE STRENGTH OF THIS WAVE AND THE AMOUNT OF PRECIP IT GENERATES AND CONTINUED THE TREND OF FAVORING A DRIER SOLUTION FOR THIS FRONT...WITH JUST SLIGHT CHANCE/LOW CHANCE POPS MENTIONED. WEDNESDAY AND THURSDAY WILL FEATURE ANOTHER DRY RIDGE OF HIGH PRESSURE MOVING THROUGH. ONLY CHANGE MADE TO BLENDED FORECAST HERE WAS TO LOWER DEWPOINTS SOME BOTH DAYS TO ACCOUNT FOR THE MIXING POTENTIAL. ALSO BLENDED IN SOME BIAS CORRECTED NUMBERS INTO THE HIGHS BOTH DAYS TO BOOST THEM BY A FEW DEGREES EACH DAY...WITH WIDESPREAD HIGHS IN THE 70S EXPECTED FOR WED/THU. NEXT ISSUE IN THE EXTENDED COMES FRIDAY WITH THE PASSAGE OF THE NEXT COLD FRONT. GIVEN THE DIFFERENCES IN THE HANDLING OF THE NEW ENGLAND H5 LOW MENTIONED IN THE SECOND PARAGRAPH...THE GFS IS QUITE A BIT FASTER WITH BRINGING THE FRONT THROUGH THAN THE ECMWF. THIS SPREAD IN THE FRONTS TIMING EXPLAINS THE NICE SMEARING OF SLIGHT CHANCE POPS ACROSS THE AREA ON FRIDAY. THIS FRONT DOES HAVE A COUPLE OF FACTORS THAT CAN GIVE ONE A LITTLE BIT MORE HOPE FOR SEEING PRECIP WITH THIS BOUNDARY AS OPPOSED TO THE ONE FOR MONDAY NIGHT. NUMBER ONE...THERE WILL BE NO UPPER LOW OVER TEXAS INTERCEPTING MOISTURE STREAMING NORTH. ALSO MAKING THE PRECIP POTENTIAL LOOK SLIGHTLY BETTER IS THAT THE LOW LEVEL CONVERGENCE LOOKS BETTER ON FRIDAY AND THIS FRONT ACTUALLY HAS SOME H85 FLOW AND MOISTURE TRANSPORT OUT AHEAD OF IT. STILL...THE AIRMASS IT WILL BE DISPLACING AGAIN LOOKS INCREDIBLY DRY AND WITH INSTABILITY LACKING...ANYTHING WE DO SEE LOOKS PRETTY LIGHT AT THIS POINT. AS FOR FIRE WEATHER CONCERNS NEXT WEEK...HUMIDITIES EACH AFTERNOON LOOK TO GET DOWN INTO THE 20S/30S. WINDS STILL LOOK LIGHT THOUGH THROUGH WEDNESDAY...BUT THURSDAY AND FRI WILL FEATURE STRONGER WINDS AND IF THE MOISTURE RETURN ENDS UP BEING RATHER LACKING...WE COULD HAVE FIRE WEATHER CONCERNS ONCE AGAIN. AT THIS POINT...THURSDAY LOOKS TO BE THE DAY THAT HAS THE GREATEST POTENTIAL TO GENERATE RED FLAG CONDITIONS AS OUR SE WINDS WILL BE EMANATING FROM A VERY DRY SFC RIDGE CENTERED OVER THE GREAT LAKES....WHILE FRIDAY AT THIS POINT LOOKS TO FEATURE HIGHER DEWPS WITH THE PASSING FRONT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 630 AM CDT SUN APR 26 2015 VFR/SKC THROUGH THE PERIOD AS A RIDGE OF HIGH PRESSURE STRETCHES ACROSS MN/WI FROM ONTARIO. NORTHERLY WINDS 5-8 KTS TODAY ACROSS EASTERN MN AND WESTERN WI WITH EASTERLY WINDS 5-8 KTS ACROSS WESTERN MN. KMSP..FEW CONCERNS THIS TAF CYCLE AS HIGH PRESSURE PREVAILS. THE WIND WILL MEANDER AROUND SOME THIS MORNING FROM 050 TO 080 AT 5 KTS OR LESS THEN BECOME MORE 030 AT 8 KTS FOR THE AFTERNOON. /OUTLOOK FOR KMSP/ MON...VFR. WINDS N 5-10 KTS. TUE...VFR. SLGT CHC OF MRNG -SHRA. WINDS NW 5-10 KTS. WED...VFR. WIND N 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...RAH LONG TERM...MPG AVIATION...RAH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1051 AM EDT SUN APR 26 2015 .SYNOPSIS... A COLD FRONT WILL SINK SOUTH ACROSS THE AREA TODAY INTO TONIGHT. DRY HIGH PRESSURE WILL MOVE INTO THE REGION MONDAY AND TUESDAY BEFORE A STORM SYSTEM IMPACTS THE AREA MID WEEK. SEASONABLE AND DRY HIGH PRESSURE IS EXPECTED TO RETURN FRIDAY INTO NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1045 AM SUNDAY...COLD FRONT IS VERY WELL DEFINED IN BOTH RADAR AND SATELLITE IMAGERY...AS WELL AS SURFACE OBS. FRONT IS STILL CREEPING SOUTHWARD AND IS JUST SOUTH OF A LINE ROUGHLY FROM OAK ISLAND TO FLORENCE SC. A THICK BLANKET OF STRATUS FOLLOWS NORTH OF THE FRONT WITH NO PRECIP PRESENT. FOR THIS MORNING...HAVE DROPPED POPS TO SLIGHT CHANCE THROUGHOUT AND CHANGED CHARACTER OF PRECIPITATION TO RAIN/DRIZZLE. THIS IS BASED ON AN ANALYSIS OF THE LATEST DATA...WHICH SHOWS A VERY STABLE ENVIRONMENT THROUGH THIS AFTERNOON. BEST CHANCE OF ANY CONVECTION REMAINS OVER OUR SOUTHERNMOST COUNTIES FOR LATE THIS AFTERNOON OR THIS EVENING WHERE TEMPERATURES WILL BE HIGHEST AND CLOUD COVER WILL NOT BE COMPLETELY OVERCAST. EVEN THIS STILL LOOKS LIKE A LOW-END PROBABILITY THOUGH. WILL TAKE ANOTHER LOOK AT TEMPS FOR TODAY WITH AN EYE TOWARDS LOWERING THEM BY A CATEGORY. PREVIOUS DISCUSSION FOLLOWS: TODAY A MIXED BAG OF WEATHER FEATURES RANGING FROM FOG TO SHOWERS TO A FEW AFTERNOON TSTMS TO A MAXIMUM TEMPERATURE DIFFERENTIAL OF NEARLY 20 DEGREES FROM THE NORTHERN INTERIOR OF SE NC TO SOUTHERN INLAND SC. NIGHT-TIME IMAGERY SHOWS WELL THE POST-FRONTAL STRATUS NORTH OF AN E TO W COLD FRONT WHICH PRESENTLY BI-SECTS OUR AREA. THIS FRONT WILL SINK SOUTH THROUGH AFTERNOON. STRONG LATE APRIL SUN WILL HEAT THE LOW- LEVELS OVER INLAND SC IN CONJUNCTION WITH LOW-LEVEL FRONTAL CONVERGENCE IN THE NEAR PEAK OF DIURNAL WARMING...SPARKING A CHANCE AT TSTMS. ALTHOUGH DRY WESTERLY FLOW ALOFT WILL LIMIT THE VERTICAL GROWTH OF CELLS...DRY AIR ENTRAINMENT AND SWIFT SEAWARD MOTION COULD BRING POTENTIALLY GUSTY WINDS TO SEVERE LIMITS...AND SPC PAINTS A MARGINAL RISK OF STORMS OVER SC. DRY LOW-LEVEL AIR FROM THE NORTH WINS OUT LATER TONIGHT AS TD VALUES DROP...WITH POST FRONTAL COOL AIR ADVECTION STABILIZING THE LOW-LEVELS AS WELL. POP VALUES DWINDLE AND PARTIAL CLEARING WILL TREND INTO EARLY MONDAY. RELATIVELY COOL MINIMUMS MONDAY OF UPPER 40S NORTH TO LOW TO MIDDLE 50S SOUTH...AND THE BEACHES. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM SUNDAY...COOL AND DRY HIGH PRESSURE WILL BUILD DOWN INTO THE CAROLINAS MONDAY AS A DEEP MID TO UPPER LOW OFF THE COAST OF NEW ENGLAND RETROGRADES BACK TOWARD THE WEST SOUTHWEST BEFORE PULLING OFF TO THE NORTHEAST BY LATE TUES. ANY LINGERING CLOUDS EARLY MONDAY WILL BE SCOURED OUT BY A DEEP NW FLOW OF DRY AND RELATIVELY COOLER AIR OVER THE AREA HOLDING ON THROUGH TUES. PCP WATER VALUES REMAIN DOWN CLOSE TO A HALF INCH MON AFTN THROUGH TUES AFTN. EXPECT PLENTY OF SUNSHINE TO OFFSET THE CAA WITH 850 TEMPS HOLD AROUND 4 TO 5 C THROUGH THE PERIOD. OVERALL EXPECT LARGE DIURNAL SWINGS IN TEMPS WITH OVERNIGHT LOWS DROPPING DOWN BELOW 50 IN MANY SPOTS ACROSS THE AREA ESPECIALLY TUES NIGHT. TEMPS WILL MAKE A RUN BACK TOWARD NORMAL BUT WILL FALL SHORT AFTER SUCH A COOL START TO THE DAY. CLOUDS WILL START INCREASING BY TUES NIGHT INTO EARLY WED AS LOW PRESSURE SYSTEM MOVES ACROSS THE GULF COAST STATES SPREADING CLOUDS AND PCP NORTHWARD. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 330 AM SUNDAY....LOW PRESSURE SYSTEM WILL RIDE ACROSS THE SOUTHERN STATES ON WED. A SHORTWAVE WILL RIDE DOWN FROM THE UPPER MID WEST AMPLIFYING THE H5 TROUGH AS IT MOVES ACROSS THE EAST COAST REACHING DOWN INTO THE GULF. THIS SHOULD GUIDE THE LOW UP THE SOUTHEAST COAST POSSIBLY MOVING DIRECTLY OVER THE CAPE FEAR COAST WED NIGHT INTO THURS MORNING. N-NE FLOW OVER THE CAROLINAS WILL BE OVERRUN BY MOIST SOUTHERLY FLOW ALOFT PRODUCING INCREASING CLOUDS AND PCP OVER THE AREA ON WED INTO THURS. THIS LOW WILL MOVE OFF TO THE NORTHEAST BUT DEEP MID TO UPPER TROUGH WILL LINGER THROUGH FRI. WILL SEE COOLER TEMPS ALONG WITH LINGERING CLOUDS AND CHC OF PCP IN THE FORECAST THROUGH THURS AND SOME CLOUDS THROUGH FRI AS THIS DEEP LOW FINALLY MAKES ITS WAY OFF TO THE EAST. SHOULD SEE A WARMING AND DRYING TREND INTO THE WEEKEND AS RIDGE BUILDS OVER THE SOUTHEAST. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... AS OF 12Z...A FRONTAL BOUNDARY IS DRAPED ACROSS THE CWA. TO THE NORTH OF THE FRONT...EXPECT IFR CONDITIONS WITH MVFR/VFR CONDITIONS SOUTH OF THE FRONT. THIS FRONT WILL DRIFT SOUTHWARD DURING THE DAY...MAINLY BASED ON THE HRRR MODEL. SOME LIGHT SHOWERS ARE EXPECTED TO DEVELOP ALONG AND BEHIND THE FRONT AS THE DAY PROGRESSES. MAINLY MVFR CONDITIONS ARE EXPECTED IN THE AFTERNOON HOURS...WITH NORTHERLY WINDS AT ALL TERMINALS WITH THE FRONT OVER THE EXTREME SOUTHERN PORTION OF THE CWA. MAY BE A BIT TOO PESSIMISTIC THIS EVENING AND WILL ADJUST ON THE NEXT SET. EXTENDED OUTLOOK...VFR MONDAY AND TUESDAY. SHOWERS POSSIBLE WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1045 AM SUNDAY...HAVE DROPPED SCEC HEADLINES WITH THE LATEST UPDATE AS SEAS ARE NOW IN THE 2 TO 4 FT RANGE WITH WINDS OF 10 TO 15 KTS. PREVIOUS DISCUSSION FOLLOWS: BLUSTERY OFFSHORE WINDS TO PREVAIL THIS MORNING AHEAD OF AND BEHIND A COLD FRONT. SEAS RUNNING 4-5 FT THIS MORNING AND AN EXERCISE CAUTION STATEMENT WILL BE NEEDED THROUGH MUCH OF THE MORNING...CURRENTLY SET TO EXPIRE AT NOON. DRIZZLE OR LIGHT RAIN MAY REDUCE VSBYS 4NM OR LESS THIS MORNING N OF CAPE FEAR. HEATING OVER INLAND SC THIS AFTERNOON COULD BRING A FEW STORMS OVER THE SC WATERS...POTENTIALLY BRING GUSTY WINDS AND SPECIAL MARINE WARNINGS MAY BE NEEDED OVER SC LATER TODAY. SEAS WILL SUBSIDE THIS AFTERNOON AS NW WINDS ABATE...BUT COULD KICK UP AGAIN TONIGHT AS N WINDS INCREASE A BIT. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM SUNDAY...HIGH PRESSURE WILL BUILD OVER THE WATERS THROUGH MON WITH DECENT SURGE OF NORTHERLY WINDS AS SHORTWAVE ROTATES AROUND MID TO UPPER TROUGH EXITING SLOWLY OFF THE NEW ENGLAND COAST. NORTHERLY WINDS WILL VEER AROUND BECOMING MORE ON SHORE BY TUES NIGHT AROUND LOW PRESSURE AS IT MAKES ITS WAY ACROSS THE GULF COAST TOWARD THE SOUTHEAST COAST. SEAS WILL BE 2 TO 4 FT MOST OF THE TIME BUT MAY REACH UP TO 5 FT IN NORTHERLY SURGE MON NIGHT. LONG TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 330 AM SUNDAY...LOW PRESSURE SYSTEM WILL MAKE ITS WAY UP THE SOUTHEAST COAST THROUGH THE PERIOD POSSIBLY TRACKING RIGHT ACROSS THE WATERS FROM SW TO NE WED NIGHT INTO THURS. WINDS WILL BE HIGHLY DEPENDENT ON TRACK AND STRENGTH OF LOW BUT FOR NOW WILL KEEP NORTHERLY FLOW OVER MOST OF LOCAL WATERS INCREASING UP TO 15 TO 20 KTS LATE WED WITH A STRONG E-SE SWELL ON FRONT END OF SYSTEM POSSIBLY DRIVING SEAS UP TOWARD SCA THRESHOLDS THROUGH WED NIGHT. SEAS WILL BE 2-4 FEET TO START WITH SPIKE WED NIGHT INTO THURS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...RGZ NEAR TERM...MJC/REK SHORT TERM...RGZ LONG TERM...RGZ AVIATION...DL MARINE...MJC/REK/RGZ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
642 AM EDT SUN APR 26 2015 .SYNOPSIS... A COLD FRONT WILL SINK SOUTH ACROSS THE AREA TODAY INTO TONIGHT. DRY HIGH PRESSURE WILL MOVE INTO THE REGION MONDAY AND TUESDAY BEFORE A STORM SYSTEM IMPACTS THE AREA MID WEEK. SEASONABLE AND DRY HIGH PRESSURE IS EXPECTED TO RETURN FRIDAY INTO NEXT WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 628 AM SUNDAY...TODAY A MIXED BAG OF WEATHER FEATURES RANGING FROM FOG TO SHOWERS TO A FEW AFTERNOON TSTMS TO A MAXIMUM TEMPERATURE DIFFERENTIAL OF NEARLY 20 DEGREES FROM THE NORTHERN INTERIOR OF SE NC TO SOUTHERN INLAND SC. NIGHT-TIME IMAGERY SHOWS WELL THE POST-FRONTAL STRATUS NORTH OF AN E TO W COLD FRONT WHICH PRESENTLY BI-SECTS OUR AREA. THIS FRONT WILL SINK SOUTH THROUGH AFTERNOON. STRONG LATE APRIL SUN WILL HEAT THE LOW- LEVELS OVER INLAND SC IN CONJUNCTION WITH LOW-LEVEL FRONTAL CONVERGENCE IN THE NEAR PEAK OF DIURNAL WARMING...SPARKING A CHANCE AT TSTMS. ALTHOUGH DRY WESTERLY FLOW ALOFT WILL LIMIT THE VERTICAL GROWTH OF CELLS...DRY AIR ENTRAINMENT AND SWIFT SEAWARD MOTION COULD BRING POTENTIALLY GUSTY WINDS TO SEVERE LIMITS...AND SPC PAINTS A MARGINAL RISK OF STORMS OVER SC. DRY LOW-LEVEL AIR FROM THE NORTH WINS OUT LATER TONIGHT AS TD VALUES DROP...WITH POST FRONTAL COOL AIR ADVECTION STABILIZING THE LOW-LEVELS AS WELL. POP VALUES DWINDLE AND PARTIAL CLEARING WILL TREND INTO EARLY MONDAY. RELATIVELY COOL MINIMUMS MONDAY OF UPPER 40S NORTH TO LOW TO MIDDLE 50S SOUTH...AND THE BEACHES. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM SUNDAY...COOL AND DRY HIGH PRESSURE WILL BUILD DOWN INTO THE CAROLINAS MONDAY AS A DEEP MID TO UPPER LOW OFF THE COAST OF NEW ENGLAND RETROGRADES BACK TOWARD THE WEST SOUTHWEST BEFORE PULLING OFF TO THE NORTHEAST BY LATE TUES. ANY LINGERING CLOUDS EARLY MONDAY WILL BE SCOURED OUT BY A DEEP NW FLOW OF DRY AND RELATIVELY COOLER AIR OVER THE AREA HOLDING ON THROUGH TUES. PCP WATER VALUES REMAIN DOWN CLOSE TO A HALF INCH MON AFTN THROUGH TUES AFTN. EXPECT PLENTY OF SUNSHINE TO OFFSET THE CAA WITH 850 TEMPS HOLD AROUND 4 TO 5 C THROUGH THE PERIOD. OVERALL EXPECT LARGE DIURNAL SWINGS IN TEMPS WITH OVERNIGHT LOWS DROPPING DOWN BELOW 50 IN MANY SPOTS ACROSS THE AREA ESPECIALLY TUES NIGHT. TEMPS WILL MAKE A RUN BACK TOWARD NORMAL BUT WILL FALL SHORT AFTER SUCH A COOL START TO THE DAY. CLOUDS WILL START INCREASING BY TUES NIGHT INTO EARLY WED AS LOW PRESSURE SYSTEM MOVES ACROSS THE GULF COAST STATES SPREADING CLOUDS AND PCP NORTHWARD. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 330 AM SUNDAY....LOW PRESSURE SYSTEM WILL RIDE ACROSS THE SOUTHERN STATES ON WED. A SHORTWAVE WILL RIDE DOWN FROM THE UPPER MID WEST AMPLIFYING THE H5 TROUGH AS IT MOVES ACROSS THE EAST COAST REACHING DOWN INTO THE GULF. THIS SHOULD GUIDE THE LOW UP THE SOUTHEAST COAST POSSIBLY MOVING DIRECTLY OVER THE CAPE FEAR COAST WED NIGHT INTO THURS MORNING. N-NE FLOW OVER THE CAROLINAS WILL BE OVERRUN BY MOIST SOUTHERLY FLOW ALOFT PRODUCING INCREASING CLOUDS AND PCP OVER THE AREA ON WED INTO THURS. THIS LOW WILL MOVE OFF TO THE NORTHEAST BUT DEEP MID TO UPPER TROUGH WILL LINGER THROUGH FRI. WILL SEE COOLER TEMPS ALONG WITH LINGERING CLOUDS AND CHC OF PCP IN THE FORECAST THROUGH THURS AND SOME CLOUDS THROUGH FRI AS THIS DEEP LOW FINALLY MAKES ITS WAY OFF TO THE EAST. SHOULD SEE A WARMING AND DRYING TREND INTO THE WEEKEND AS RIDGE BUILDS OVER THE SOUTHEAST. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AS OF 12Z...A FRONTAL BOUNDARY IS DRAPED ACROSS THE CWA. TO THE NORTH OF THE FRONT...EXPECT IFR CONDITIONS WITH MVFR/VFR CONDITIONS SOUTH OF THE FRONT. THIS FRONT WILL DRIFT SOUTHWARD DURING THE DAY...MAINLY BASED ON THE HRRR MODEL. SOME LIGHT SHOWERS ARE EXPECTED TO DEVELOP ALONG AND BEHIND THE FRONT AS THE DAY PROGRESSES. MAINLY MVFR CONDITIONS ARE EXPECTED IN THE AFTERNOON HOURS...WITH NORTHERLY WINDS AT ALL TERMINALS WITH THE FRONT OVER THE EXTREME SOUTHERN PORTION OF THE CWA. MAY BE A BIT TOO PESSIMISTIC THIS EVENING AND WILL ADJUST ON THE NEXT SET. EXTENDED OUTLOOK...VFR MONDAY AND TUESDAY. SHOWERS POSSIBLE WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 628 AM SUNDAY...BLUSTERY OFFSHORE WINDS TO PREVAIL THIS MORNING AHEAD OF AND BEHIND A COLD FRONT. SEAS RUNNING 4-5 FT THIS MORNING AND AN EXERCISE CAUTION STATEMENT WILL BE NEEDED THROUGH MUCH OF THE MORNING...CURRENTLY SET TO EXPIRE AT NOON. DRIZZLE OR LIGHT RAIN MAY REDUCE VSBYS 4NM OR LESS THIS MORNING N OF CAPE FEAR. HEATING OVER INLAND SC THIS AFTERNOON COULD BRING A FEW STORMS OVER THE SC WATERS...POTENTIALLY BRING GUSTY WINDS AND SPECIAL MARINE WARNINGS MAY BE NEEDED OVER SC LATER TODAY. SEAS WILL SUBSIDE THIS AFTERNOON AS NW WINDS ABATE...BUT COULD KICK UP AGAIN TONIGHT AS N WINDS INCREASE A BIT. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 330 AM SUNDAY...HIGH PRESSURE WILL BUILD OVER THE WATERS THROUGH MON WITH DECENT SURGE OF NORTHERLY WINDS AS SHORTWAVE ROTATES AROUND MID TO UPPER TROUGH EXITING SLOWLY OFF THE NEW ENGLAND COAST. NORTHERLY WINDS WILL VEER AROUND BECOMING MORE ON SHORE BY TUES NIGHT AROUND LOW PRESSURE AS IT MAKES ITS WAY ACROSS THE GULF COAST TOWARD THE SOUTHEAST COAST. SEAS WILL BE 2 TO 4 FT MOST OF THE TIME BUT MAY REACH UP TO 5 FT IN NORTHERLY SURGE MON NIGHT. LONG TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 330 AM SUNDAY...LOW PRESSURE SYSTEM WILL MAKE ITS WAY UP THE SOUTHEAST COAST THROUGH THE PERIOD POSSIBLY TRACKING RIGHT ACROSS THE WATERS FROM SW TO NE WED NIGHT INTO THURS. WINDS WILL BE HIGHLY DEPENDENT ON TRACK AND STRENGTH OF LOW BUT FOR NOW WILL KEEP NORTHERLY FLOW OVER MOST OF LOCAL WATERS INCREASING UP TO 15 TO 20 KTS LATE WED WITH A STRONG E-SE SWELL ON FRONT END OF SYSTEM POSSIBLY DRIVING SEAS UP TOWARD SCA THRESHOLDS THROUGH WED NIGHT. SEAS WILL BE 2-4 FEET TO START WITH SPIKE WED NIGHT INTO THURS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...MJC SHORT TERM...RGZ LONG TERM...RGZ AVIATION...43
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1022 AM EDT SUN APR 26 2015 .SYNOPSIS... A SLOW MOVING UPPER LEVEL TROUGH OVER THE NORTHEASTERN UNITED STATES AND COOL AIR ALOFT WILL FAVOR UNSEASONABLY CHILLY TEMPERATURES WITH PERIODS OF SHOWERY WEATHER THROUGH THE END OF THIS MONTH. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A SPRAWLING UPPER LOW OVER THE CANADIAN MARITIMES WILL CONTROL THE PATTERN FOR THE NEXT COUPLE OF DAYS AT LEAST. THE MAIN EFFECT WILL TO FUNNEL A SERIES OF UPPER SHORTWAVES DOWN OUT OF NEW YORK/EASTERN CANADA AND KEEP A FAIR AMOUNT OF CLOUDINESS AND THE CHANCE FOR SHOWERS IN THE FORECAST. THE FIRST SYSTEM CAN BE SEEN ON SATELLITE AS AN AREA OF CLOUDINESS DROPPING SOUTH INTO NRN PA. THE COARSER RESOLUTION MODELS CREATE SOME LIGHT QPF AND THE HRRR HINTS AT SOME SMALL CELLULAR ACTIVITY AT MAX HEATING. IT MAKES SENSE WITH THE COLD AIR ALOFT AND THE STRONG LATE APRIL SUN. I DON`T FEEL CONFIDENT IN MEASURING ANYWHERE HOWEVER SO WILL JUST KEEP THE MENTION OF SPRINKLES FOR NOW. 00Z GEFS MEAN 8H TEMPS SUPPORT MAX TEMPS FROM NR 50F ACROSS THE NW MTNS...TO NR 60F ACROSS THE LOWER SUSQ VALLEY...STILL WELL BLW NORMAL FOR LATE APRIL. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... CONTINUED COOLING ALOFT WILL LEAD TO A GRADUAL TREND TWD BKN-OVC SKIES WITH ISOLATED TO SCTD -SHRA LATE TONIGHT /BUT MORE LIKELY AFTER SUNRISE MONDAY/. COLD BLYR TEMPS WITH ZERO DEG C WET BULB HEIGHT ONLY 1-2KFT AGL WILL COMBINE WITH TEMPS IN THE 30S ACROSS THE LAUREL HIGHLANDS AND NW MTNS TO ALLOW WET SNOW TO MIX IN WITH THE SHOWERS...ESP AT ELEVATIONS AOA 2000 MSL. SFC TEMPS CLIMBING INTO THE 40S TO NEAR 50F MONDAY AFTERNOON /AND THE ZERO WET BULB HEIGHT RISING TO BETWEEN 2-3 KFT AGL/ WILL SUPPORT PLAIN RAIN SHOWERS MONDAY AFTERNOON AND EVENING. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... ACTIVE NORTHERN AND SOUTHERN STREAM SPLIT FLOW PATTERN ACROSS NORTH AMERICA WILL KEEP THE REGION IN UPPER LEVEL TROFFINESS THROUGH MUCH OF THE PERIOD. THE BLOCKED UP NRN STREAM...GENERALLY NW FLOW PATTERN OVER THE NORTHEAST WILL TEND TO SHUNT SRN STREAM SYSTEM TO THE SOUTH OF PA. EARLY NEXT WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...THIS LOW FINALLY LIFTS OUT FOR GOOD..BUT DIGGING TROUGH FROM UPPER MIDWEST WILL EXTEND INTO THE SOUTHEAST U.S. BY LATE WEEK...COMBINED WITH A SOUTHERN STREAM SHORTWAVE LIFTING OUT OF THE S PLAINS TOWARD THE E COAST WILL BRING POSSIBILITY OF A DEVELOPING STORM SLIDING NORTHEASTWARD OFF THE EASTERN SEABOARD. TRACK/STRENGTH STILL QUITE UNCERTAIN...BUT AT THIS TIME LOOKS LIKE WE/LL BE BETWEEN THAT LOW PRESSURE AREA AND A HIGH OVER OHIO VALLEY...LIKELY KEEPING CLOUDS AND SCT SHOWERS AROUND AS TEMPS COOL BACK DOWN A BIT. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... WIDESPREAD VFR CONDITIONS WITH MINIMAL CLOUD COVER AND LIGHT WINDS WILL GIVE WAY TO HIGHER BASED CEILINGS OVER CENTRAL AND NORTHERN AREAS AS A WEAK DISTURBANCE DROPS SOUTH OUT OF NY. BY MID DAY A SCT-BKN 4000-5000FT DECK WILL DEVELOP ACROSS NORTHERN/WESTERN HIGHER TERRAIN AS COOLER AIR ALOFT BEGINS TO ARRIVE. CEILINGS WILL LOWER ACROSS THE NORTHERN MTNS AND LAUREL HIGHLANDS TONIGHT WITH RESTRICTIONS DEVELOPING IN THE EVENING AT KBFD AND AFTER MIDNIGHT AT KJST. SCT LIGHT RAIN/SNOW SHOWERS WILL ALSO MOVE INTO THESE AREAS FROM THE NORTH. ELSEWHERE... CONDITIONS SHOULD REMAIN VFR THROUGH THE OVERNIGHT BEFORE RESTRICTIONS BECOME POSS ON MONDAY. OUTLOOK... MON...AREAS OF MVFR WITH SCT/NUMEROUS RAIN OR SNOW SHOWERS...MAINLY ACROSS WESTERN/NORTHERN HIGHER TERRAIN. TUE...AREAS OF MVFR WITH SCT LIGHT RAIN SHOWERS. IMPROVING TO VFR LATE. WED...NO SIG WX. THU...MVFR POSS IN SCT RAIN SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE/RXR
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1003 AM CDT SUN APR 26 2015 .UPDATE...CORRECTED... MONITORING WHAT COULD BE A VERY ACTIVE AFTERNOON FOR SOUTH CENTRAL TEXAS. THROUGH MID MORNING...SHOWERS AND STORMS HAVE ALONG THE EASTERN HALF OF THE CWA IN A VERY MOIST BOUNDARY LAYER ENVIRONMENT. EML CAPPING/MID LEVEL DRY AIR IS LIMITING THE INTENSITY OF THIS DEVELOPMENT CURRENTLY BUT IT MAY BE A FOREWARNING OF THINGS TO COME THIS AFTERNOON AS THE CAP IS FORECAST TO ERODE BY EARLY AFTERNOON. ALSO BY EARLY AFTERNOON...THE DRYLINE CURRENTLY LOCATED JUST EAST OF THE BIG BEND AREA THROUGH MIDLAND WILL PROGRESS EASTWARD INTO THE EASTERN PORTIONS OF THE CWA AS FAVORABLE BOUNDARY LAYER FLOW ORIENTATION COULD RESULT IN A VERTICALLY VEERED PROFILE AND CONVERGENCE ALONG THE DRYLINE. AS THE MORNING CLOUD COVER MIXES OUT AND CAPPING DETERIORATES BY EARLY AFTERNOON...AN AREA EAST OF DEL RIO TO SONORA WILL BE A FOCUS FOR ISOLATED...BUT POTENTIALLY RAPIDLY DEVELOPING CONVECTION WITH THE PROSPECT OF LARGE HAIL...DAMAGING WINDS...AND POTENTIALLY SOME TORNADIC DEVELOPMENT THROUGH THE AFTERNOON. WHILE LATEST SHORT TERM MODELS SUGGEST CONVECTION SHOULD STAY NORTH OF THE I-10 CORRIDOR...DO THINK THE DECENT SHOT AT SEVERE POTENTIAL COULD EXTEND SOUTH TO THE HWY 57 CORRIDOR THIS AFTERNOON. SINCE HI RES MODELS SUCH AS TTU WRF AND HRRR ARE KEEPING CI WELL NORTH OF THE CWA THIS AFTERNOON...DID NOT INCREASE POPS ABOVE CHC WORDING THROUGH 00Z. BUT AS SPC HAS INCLUDED THE SAME GENERAL LOCATIONS PREVIOUSLY MENTIONED IN THE ENHANCED RISK...WOULD NOT BE SURPRISED TO SEE SOME ACTIVITY FURTHER SOUTH INTO OUR CWA THIS AFTERNOON. AS FOR OVERNIGHT STORM POTENTIAL...PREVIOUS FORECAST SEEMS TO BE ON TRACK WITH LATEST SHORT TERM MODEL RUNS. CONFIDENCE IS INCREASING FOR A LATE EVENING AND OVERNIGHT LINE OF POTENTIALLY SEVERE STORMS...MORE AS A STRAIGHT LINE WIND THREAT WITH LARGE HAIL AS WELL. TB && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 88 67 85 59 71 / 40 50 30 20 10 AUSTIN BERGSTROM INTL AIRPORT 86 66 83 58 72 / 40 50 30 20 10 NEW BRAUNFELS MUNI AIRPORT 87 67 85 59 74 / 40 50 30 10 10 BURNET MUNI AIRPORT 86 62 83 56 70 / 50 50 30 30 10 DEL RIO INTL AIRPORT 90 62 87 60 77 / 20 20 10 - 10 GEORGETOWN MUNI AIRPORT 87 65 83 57 69 / 50 50 30 30 10 HONDO MUNI AIRPORT 88 65 85 59 75 / 40 40 20 - 10 SAN MARCOS MUNI AIRPORT 87 67 84 60 73 / 40 50 30 10 10 LA GRANGE - FAYETTE REGIONAL 86 69 82 62 73 / 40 50 50 20 10 SAN ANTONIO INTL AIRPORT 88 68 86 61 74 / 40 40 20 10 10 STINSON MUNI AIRPORT 88 69 85 62 75 / 40 40 30 10 10 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...24 SYNOPTIC/GRIDS...03 PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
957 AM CDT SUN APR 26 2015 .UPDATE... MONITORING WHAT COULD BE A VERY ACTIVE AFTERNOON FOR SOUTH CENTRAL TEXAS. THROUGH MID MORNING...SHOWERS AND STORMS HAVE ALONG THE EASTERN HALF OF THE CWA IN A VERY MOIST BOUNDARY LAYER ENVIRONMENT. EML CAPPING/MID LEVEL DRY AIR IS LIMITING THE INTENSITY OF THIS DEVELOPMENT CURRENTLY BUT IT MAY BE A FOREWARNING OF THINGS TO COME THIS AFTERNOON AS THE CAP IS FORECAST TO ERODE BY EARLY AFTERNOON. ALSO BY EARLY AFTERNOON...THE DRYLINE CURRENTLY LOCATED JUST EAST OF THE BIG BEND AREA THROUGH MIDLAND WILL PROGRESS EASTWARD INTO THE EASTERN PORTIONS OF THE CWA AS FAVORABLE BOUNDARY LAYER FLOW ORIENTATION COULD RESULT IN A VERTICALLY VEERED PROFILE AND CONVERGENCE ALONG THE DRYLINE. AS THE MORNING CLOUD COVER MIXES OUT AND CAPPING DETERIORATES BY EARLY AFTERNOON...AN AREA EAST OF DEL RIO TO SONORA WILL BE A FOCUS FOR ISOLATED...BUT POTENTIALLY RAPIDLY DEVELOPING CONVECTION WITH THE PROSPECT OF LARGE HAIL...DAMAGING WINDS...AND POTENTIALLY SOME TORNADIC DEVELOPMENT THROUGH THE AFTERNOON. THINK THE BEST SHOT AT SEVERE POTENTIAL WILL BE MAINLY NORTH OF THE I-10 CORRIDOR THIS AFTERNOON. HOWEVER INSTABILITY AND MOISTURE ALONE COULD PRODUCE ISOLATED SEVERE CELLS ACROSS MUCH OF THE CWA. LUCKILY...HI RES MODELS SUCH AS TTU WRF AND HRRR ARE KEEPING CI WELL NORTH OF THE CWA THIS AFTERNOON AND AS SUCH...DID NOT INCREASE POPS ABOVE CHC WORDING. BUT AS SPC HAS INCLUDED THE SAME GENERAL LOCATIONS PREVIOUSLY MENTIONED IN THE ENHANCED RISK...WOULD NOT BE SURPRISED TO SEE SOME ACTIVITY FURTHER SOUTH INTO OUR CWA THIS AFTERNOON. AS FOR OVERNIGHT STORM POTENTIAL...PREVIOUS FORECAST SEEMS TO BE ON TRACK WITH LATEST SHORT TERM MODEL RUNS. CONFIDENCE IS INCREASING OF A LATE EVENING AND OVERNIGHT LINE OF POTENTIALLY SEVERE STORMS...MORE AS A STRAIGHT LINE WIND THREAT WITH LARGE HAIL AS WELL. TB && .PREV DISCUSSION... /ISSUED 652 AM CDT SUN APR 26 2015/ AVIATION... THERE ARE LOW CIGS THIS MORNING AT ALL TERMINALS. EXPECT THIS TO BE THE CASE UNTIL LATER THIS MORNING. THERE WILL BE VFR CONDITIONS THROUGH THE AFTERNOON AND MOST OF THE EVENING. THERE IS A CHANCE FOR THUNDERSTORMS THIS AFTERNOON IN SAN ANTONIO AND AUSTIN...BUT PROBABILITY IS TOO LOW TO INCLUDE IN TAFS. CIGS WILL DROP TO MVFR BY AROUND MIDNIGHT TONIGHT IN AUSTIN AND SAN ANTONIO. THERE IS A BETTER CHANCE FOR THUNDERSTORMS MONDAY MORNING. PREV DISCUSSION... /ISSUED 405 AM CDT SUN APR 26 2015/ SHORT TERM (TODAY THROUGH MONDAY)... A HUMID AIRMASS HAS SURGED BACK NORTH ACROSS SOUTH CENTRAL TEXAS EARLY THIS MORNING ON A STRENGTHENING SOUTHERLY LOWER LEVEL FLOW AHEAD OF AN UPPER LEVEL TROUGH DRIFTING TO THE EAST ACROSS THE DESERT SOUTHWEST. ANOTHER PERIOD OF ACTIVE CONVECTIVE WEATHER IS POSSIBLE IN THE SHORT TERM. THE DRYLINE SLOWLY MOVES TO THE EAST ACROSS SOUTH CENTRAL TEXAS AS THE UPPER LEVEL TROUGH MOVES TO THE SOUTHERN PLAINS ON MONDAY. MOISTURE CONVERGENCE ALONG AND AHEAD OF THE DRYLINE WILL ALLOW FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS LATE THIS MORNING THROUGH MONDAY. THE MOST ACTIVE PERIOD WILL BE OVERNIGHT INTO EARLY MONDAY MORNING WHEN UPWARD MOTION IS MAXIMIZED BY THE DRYLINE AND TROUGH AXIS PASSAGE ALONG WITH FAVORABLE UPPER LEVEL JET ENERGY. CAPES OF 1000 TO 3000 J/KG AND DEEP LAYER SHEAR INDICATE A FEW STRONG TO SEVERE STORMS ARE POSSIBLE. ABOVE AVERAGE TEMPERATURES ARE EXPECTED UNTIL A COLD FRONT PASSAGE LATE ON MONDAY. LONG TERM (MONDAY NIGHT THROUGH SATURDAY)... THE FRONT CLEARS SOUTH CENTRAL TEXAS MONDAY EVENING LEADING TO BREEZY NORTHERLY WINDS MONDAY NIGHT INTO TUESDAY. PROXIMITY TO THE UPPER TROUGH MAY ALLOW FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ACROSS NORTHEASTERN AREAS OF SOUTH CENTRAL TEXAS MONDAY NIGHT. MODELS SHOWING LESS RAINFALL POTENTIAL FOR TUESDAY AS THE UPPER LEVEL TROUGH CONTINUES TO THE EAST AND HAVE REMOVED MENTION. THE REMAINDER OF THE FORECAST IS RAIN FREE AS AN UPPER LEVEL RIDGE SLOWLY MOVES OVER TEXAS AND A MUCH DRIER AIRMASS FILTERS INTO OUR AREA. A COOL SURFACE HIGH BRINGS WELL BELOW AVERAGE TEMPERATURES MID WEEK WITH LOWS IN THE MID TO UPPER 40S IN PARTS OF THE HILL COUNTRY. THE SURFACE HIGH DRIFTS OFF TO THE EAST ALLOWING FOR SOUTHERLY FLOW TO RETURN LEADING TO A WARMING TREND. ANOTHER CHANCE OF RAIN IS POSSIBLE IN THE DAYS BEYOND THIS FORECAST. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 88 67 85 59 71 / 40 50 30 20 10 AUSTIN BERGSTROM INTL AIRPORT 86 66 83 58 72 / 40 50 30 20 10 NEW BRAUNFELS MUNI AIRPORT 87 67 85 59 74 / 40 50 30 10 10 BURNET MUNI AIRPORT 86 62 83 56 70 / 50 50 30 30 10 DEL RIO INTL AIRPORT 90 62 87 60 77 / 20 20 10 - 10 GEORGETOWN MUNI AIRPORT 87 65 83 57 69 / 50 50 30 30 10 HONDO MUNI AIRPORT 88 65 85 59 75 / 40 40 20 - 10 SAN MARCOS MUNI AIRPORT 87 67 84 60 73 / 40 50 30 10 10 LA GRANGE - FAYETTE REGIONAL 86 69 82 62 73 / 40 50 50 20 10 SAN ANTONIO INTL AIRPORT 88 68 86 61 74 / 40 40 20 10 10 STINSON MUNI AIRPORT 88 69 85 62 75 / 40 40 30 10 10 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...24 SYNOPTIC/GRIDS...03 PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1231 PM MDT SUN APR 26 2015 .UPDATE... ISSUED AT 1231 PM MDT SUN APR 26 2015 UPDATE ISSUED TO REDUCE HIGH TEMPERATURES ACROSS THE AREA BASED ON PERSISTENT CLOUD COVER THRU THE DAY THUS FAR. AS A RESULT...ALL AREAS HAVE SEEN A COUPLE DEGREES DROP BASED OFF OF LATEST OBS TREND IN PAST SEVERAL HRS. REST OF FORECAST UNCHANGED. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 419 AM MDT SUN APR 26 2015 MAIN FORECAST CONCERNS WILL BE GRADIENT OF PRECIPITATION CHANCES INTO MONDAY AND HIGH TEMPERATURES TODAY/MONDAY. SATELLITE SHOWING THE FLOW HAS BECOME MORE AMPLIFIED FROM THE PACIFIC INTO THE WESTERN ATLANTIC OVER THE LAST 24 HOURS. SPLIT FLOW CONTINUES OVER THE WESTERN PORTION OF COUNTRY WITH EXPECTED SOUTHERN CUTOFF LOW NOW STARTING TO MOVE INTO ARIZONA/NEW MEXICO. NATURE OF FLOW WHICH IN SOME RESPECTS IS RETROGRESSING A LITTLE WOULD INDICATE THE PATTERN IS GOING TO BE SLOW TO CHANGE. COLD FRONT HAS MOVED THROUGH WITH UPSLOPE WINDS AND STRATUS ENTRENCHED ACROSS THE AREA. AT JET LEVEL...MODELS HANDLED THIS WELL THE GFS THE WORST AND TOO STRONG. AT MID LEVELS...MODELS WERE HAVING A LITTLE TROUBLE WITH THE DEVELOPING WESTERN TROUGH. THEY TENDED TO BE TOO DEEP WITH THE NAM THE WORST. OUTSIDE OF THIS THE NAM WAS NOT DOING TOO BAD. OVERALL THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND UKMET. THE CANADIAN WERE DOING THE WORST. MODELS HAD SURFACE LOW TO OUR SOUTHWEST TOO FAR NORTH. THE RUC AND ECMWF WERE DOING THE BEST. THE MODELS WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD WITH THE GFS...CANADIAN...SREF AND NAM DOING THE BEST. TODAY/TONIGHT...MAJORITY OF CONVECTION DURING THE EVENING STAYED MOSTLY TO THE WEST. UPSTREAM SOUNDINGS/UPPER AIR ANALYSIS TO THE SOUTH THROUGH THE WEST NOT PAINTING/SUPPORTING A WET FORECAST WITH A VERY DEEP DRY LAYER AND WHAT MOISTURE THERE IS AT 700 MB AT ITS LOWEST. IT LOOKS LIKE A LOT OF DRY AIR GETS PULLED INTO THE AREA BEFORE THE ARRIVAL OF ANY SIGNIFICANT DYNAMICS. UPPER AIR ANALYSIS SUPPORTS A RATHER FAR SOUTH SOLUTION OF THE EVENTUAL UPPER LOW WITH THE LARGEST HEIGHT FALLS OVER ARIZONA. NEW MODEL SUITE SUPPORTS WHAT THE ANALYSIS IS SHOWING. MAIN AREA OF PRECIPITATION HAS STAYED TO THE NORTH AND WEST OF THE AREA ALL NIGHT WITH ONLY A FEW RAIN SHOWERS ALONG WITH AREAS OF DRIZZLE AND FOG IN THE SATURATED LOW LEVELS. DYNAMICS TO OUR WEST BEGINS TO AFFECT MOST OF THE WESTERN TWO THIRDS OF THE FORECAST AREA THROUGH THE MIDDLE OF THE DAY BEFORE SOME DRYING ALOFT OCCUR AS THE LIFT MOVES AWAY FROM THE AREA. BASED ON THE LATEST MODEL DATA AND OBSERVATIONAL TRENDS...SHOULD HAVE A WIDE VARIETY OF WEATHER THIS MORNING. AREAS OF FOG AND DRIZZLE ALONG WITH SOME RAIN SHOWERS SHOULD PERSIST DURING THE MORNING. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT WITH ELEVATED CAPE AND FAVORABLE LAPSE RATES IN PLACE. WILL BE A LULL IN THE PRECIPITATION FOR MOST OF THE REST OF THE DAY. AS HAS BEEN THE CASE THE LAST FEW DAYS...THE FAR WEST AND SOUTHWEST WILL HAVE THE BEST CHANCE OF PRECIPITATION DURING THIS TIME. CLOUD COVER SHOULD STAY THICK MOST OF THE DAY WITH MAYBE SOME CLEARING IN THE FAR EASTERN PORTION AS A LITTLE DRIER AIR MOVES IN TO THERE. KEPT THE COOLER TEMPERATURES IN PLACE WITH COOLEST READINGS IN THE FAR WEST WHERE TEMPERATURES MAY NEED NOT GET OUT OF THE 40S. SOUTHERN CUTOFF LOW GETS ORGANIZED AND IN A DECENT POSITION TO GIVE THE AREA SOME LIGHT PRECIPITATION LATER THIS AFTERNOON INTO TONIGHT...ESPECIALLY IN THE SOUTHWEST THIRD TO HALF. THE BEST CHANCE OF PRECIPITATION LOOKS TO OCCUR FROM EARLY EVENING TO NEAR 09Z AS THE BEST/DEEPEST MOISTURE GETS IN PLACE. AFTER THAT THE MOISTURE AND PRECIPITATION STARTS ITS GRADUAL SLIDE TO THE SOUTH AND EAST. MONDAY/MONDAY NIGHT...UPPER SYSTEM AND ASSOCIATED MOISTURE AND PRECIPITATION CONTINUES ITS SHIFT SOUTH AND EAST AS THE EXITING SYSTEM MOVES AWAY. ONCE AGAIN THE FAR SOUTH AND SOUTHWEST WILL HAVE THE BEST CHANCE FOR LIGHT PRECIPITATION. CLEARING WILL ALSO BEGIN WITH MOST OF THE NORTH HALF GETTING A LOT OF SUNSHINE BY THE MIDDLE OF THE DAY. COULD BE QUITE A GRADIENT WITH THE HIGH TEMPERATURES WITH THE NORTH THE WARMEST AS IT SEES THE MOST SUN. LINGERING SPOTTY PRECIPITATION SHOULD END BY LATE IN THE EVENING. DEPENDING ON HOW FAST IT CLEARS...TEMPERATURES COULD GET QUITE CHILLY WITH A VERY LIGHT WIND FIELD IN PLACE. TUESDAY/TUESDAY NIGHT...UPPER RIDGE AND NORTHERLY FLOW MOVE INTO THE AREA DURING THIS PERIOD. THIS SHOULD ALLOW FOR A DECENT AMOUNT OF SUN. ONE THING THAT COULD SPOIL THAT WILL BE A LEFT FRONT QUADRANT THAT MOVES IN AND SPREADS SOME CLOUDS INTO THE NORTHERN HALF OF THE AREA. ECMWF IS PRODUCING SOME LIGHT QPF. HOWEVER...THERE IS NO INSTABILITY AND A RATHER DEEP DRY LAYER. SO IT SHOULD STAY DRY. TEMPERATURES SHOULD WARM DUE TO SUNSHINE BUT WILL BE TEMPERED BY THE UNFAVORABLE SURFACE WIND FIELD. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 419 AM MDT SUN APR 26 2015 A RIDGE WILL CONTINUE BUILDING INTO THE PLAINS ON WEDNESDAY AS ANOTHER SYSTEM MOVES IN OVER THE PACIFIC NORTHWEST. DRY CONDITIONS ARE EXPECTED TO LAST THROUGH FRIDAY MORNING AS THE RIDGE PUSHES FURTHER EAST. PRECIP CHANCES MOVE INTO THE WESTERN CWA FRIDAY AFTERNOON AS THE PAC NW TROUGH MOVES INTO THE ROCKIES AND SWRLY UPPER LEVEL FLOW DEVELOPS. SLIGHT CHANCE OF PRECIP IS KEPT THROUGH THE END OF THE PERIOD FOR THE FORECAST AREA WITH SHORTWAVES POSSIBLY GENERATING SHOWERS AND THUNDERSTORMS AS THE TROUGH MOVES INTO THE PLAINS. WARMER TEMPERATURES ARE EXPECTED DURING THIS PERIOD WITH HIGHS IN THE 70S. READINGS IN THE LOW 80S ARE POSSIBLE BY THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1130 AM MDT SUN APR 26 2015 FOR KGLD...THRU 12Z MONDAY CEILINGS WILL RANGE FROM OVC002-007 IN DRIZZLE AND FOG THAT DROPS VISIBILITY IN A 2-6 MILE RANGE. AFT 12Z MONDAY...MVFR CONDITIONS WITH OVC015 AND VCSH. WINDS ENE THRU FORECAST PERIOD 10-20KTS...HIGHEST BEFORE 00Z MONDAY...AND AFTER 12Z MONDAY. FOR KMCK...SLOW INCREASING TREND IN CEILINGS HEIGHTS THRU FORECAST PERIOD. LOOKING FOR MVFR/IFR MIX THRU 03Z...THEN TRENDING TO MVFR BKN030 THRU 09Z...THEN VFR AT BKN035. SOME DRIZZLE THROUGH 22Z WITH 5SM IN FOG. WINDS ENE 10-20KTS...MOST GUSTS NEAR 20KTS THROUGH 22Z THIS AFTERNOON. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...BULLER LONG TERM...JBH AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1130 AM MDT SUN APR 26 2015 .UPDATE... ISSUED AT 948 AM MDT SUN APR 26 2015 UPDATE ISSUED TO DECREASE PRECIP COVERAGE THRU REST OF MORNING HRS BASED ON LATEST RADAR TRENDS. HAVE OPTED TO REMOVE MENTION OF HIGHER POPS/THUNDER FROM THE ENTIRE CWA FORECAST REST OF MORNING INTO THE EARLY AFTERNOON. THE MORNING HRS HERE IN THE CWA HAVE BEEN PERSISTENT FOG AND MAINLY DRIZZLE. MOST APPRECIABLE RETURNS HAVE BEEN FOCUSED OVER THE CENTRAL ROCKIES AROUND THE UPPER LOW. EASTERLY FLOW OVER THE CWA HAVE AIDED IN UPSLOPE CONDITIONS KEEPING PRECIP FOCUSED WEST OF OUR CWA BORDERS. AM EXPECTING AN INCREASE LATER IN THE AFTERNOON THOUGH AS UPPER LOW PIVOTS OUT ONTO THE PLAINS. HAVE SHOWN INCREASING POPS TOWARDS THAT TIMEFRAME AS WELL AS A FEW HOURS WHERE THUNDER IS POSSIBLE WITH INCREASED INSTABILITY WITH LOW PROXIMITY. REST OF FORECAST FOR TEMPS/WINDS REMAIN ON TRACK. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 419 AM MDT SUN APR 26 2015 MAIN FORECAST CONCERNS WILL BE GRADIENT OF PRECIPITATION CHANCES INTO MONDAY AND HIGH TEMPERATURES TODAY/MONDAY. SATELLITE SHOWING THE FLOW HAS BECOME MORE AMPLIFIED FROM THE PACIFIC INTO THE WESTERN ATLANTIC OVER THE LAST 24 HOURS. SPLIT FLOW CONTINUES OVER THE WESTERN PORTION OF COUNTRY WITH EXPECTED SOUTHERN CUTOFF LOW NOW STARTING TO MOVE INTO ARIZONA/NEW MEXICO. NATURE OF FLOW WHICH IN SOME RESPECTS IS RETROGRESSING A LITTLE WOULD INDICATE THE PATTERN IS GOING TO BE SLOW TO CHANGE. COLD FRONT HAS MOVED THROUGH WITH UPSLOPE WINDS AND STRATUS ENTRENCHED ACROSS THE AREA. AT JET LEVEL...MODELS HANDLED THIS WELL THE GFS THE WORST AND TOO STRONG. AT MID LEVELS...MODELS WERE HAVING A LITTLE TROUBLE WITH THE DEVELOPING WESTERN TROUGH. THEY TENDED TO BE TOO DEEP WITH THE NAM THE WORST. OUTSIDE OF THIS THE NAM WAS NOT DOING TOO BAD. OVERALL THE GFS WAS DOING A LITTLE BETTER THAN THE ECMWF AND UKMET. THE CANADIAN WERE DOING THE WORST. MODELS HAD SURFACE LOW TO OUR SOUTHWEST TOO FAR NORTH. THE RUC AND ECMWF WERE DOING THE BEST. THE MODELS WERE DOING WELL ON THE LOW LEVEL THERMAL FIELD WITH THE GFS...CANADIAN...SREF AND NAM DOING THE BEST. TODAY/TONIGHT...MAJORITY OF CONVECTION DURING THE EVENING STAYED MOSTLY TO THE WEST. UPSTREAM SOUNDINGS/UPPER AIR ANALYSIS TO THE SOUTH THROUGH THE WEST NOT PAINTING/SUPPORTING A WET FORECAST WITH A VERY DEEP DRY LAYER AND WHAT MOISTURE THERE IS AT 700 MB AT ITS LOWEST. IT LOOKS LIKE A LOT OF DRY AIR GETS PULLED INTO THE AREA BEFORE THE ARRIVAL OF ANY SIGNIFICANT DYNAMICS. UPPER AIR ANALYSIS SUPPORTS A RATHER FAR SOUTH SOLUTION OF THE EVENTUAL UPPER LOW WITH THE LARGEST HEIGHT FALLS OVER ARIZONA. NEW MODEL SUITE SUPPORTS WHAT THE ANALYSIS IS SHOWING. MAIN AREA OF PRECIPITATION HAS STAYED TO THE NORTH AND WEST OF THE AREA ALL NIGHT WITH ONLY A FEW RAIN SHOWERS ALONG WITH AREAS OF DRIZZLE AND FOG IN THE SATURATED LOW LEVELS. DYNAMICS TO OUR WEST BEGINS TO AFFECT MOST OF THE WESTERN TWO THIRDS OF THE FORECAST AREA THROUGH THE MIDDLE OF THE DAY BEFORE SOME DRYING ALOFT OCCUR AS THE LIFT MOVES AWAY FROM THE AREA. BASED ON THE LATEST MODEL DATA AND OBSERVATIONAL TRENDS...SHOULD HAVE A WIDE VARIETY OF WEATHER THIS MORNING. AREAS OF FOG AND DRIZZLE ALONG WITH SOME RAIN SHOWERS SHOULD PERSIST DURING THE MORNING. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT WITH ELEVATED CAPE AND FAVORABLE LAPSE RATES IN PLACE. WILL BE A LULL IN THE PRECIPITATION FOR MOST OF THE REST OF THE DAY. AS HAS BEEN THE CASE THE LAST FEW DAYS...THE FAR WEST AND SOUTHWEST WILL HAVE THE BEST CHANCE OF PRECIPITATION DURING THIS TIME. CLOUD COVER SHOULD STAY THICK MOST OF THE DAY WITH MAYBE SOME CLEARING IN THE FAR EASTERN PORTION AS A LITTLE DRIER AIR MOVES IN TO THERE. KEPT THE COOLER TEMPERATURES IN PLACE WITH COOLEST READINGS IN THE FAR WEST WHERE TEMPERATURES MAY NEED NOT GET OUT OF THE 40S. SOUTHERN CUTOFF LOW GETS ORGANIZED AND IN A DECENT POSITION TO GIVE THE AREA SOME LIGHT PRECIPITATION LATER THIS AFTERNOON INTO TONIGHT...ESPECIALLY IN THE SOUTHWEST THIRD TO HALF. THE BEST CHANCE OF PRECIPITATION LOOKS TO OCCUR FROM EARLY EVENING TO NEAR 09Z AS THE BEST/DEEPEST MOISTURE GETS IN PLACE. AFTER THAT THE MOISTURE AND PRECIPITATION STARTS ITS GRADUAL SLIDE TO THE SOUTH AND EAST. MONDAY/MONDAY NIGHT...UPPER SYSTEM AND ASSOCIATED MOISTURE AND PRECIPITATION CONTINUES ITS SHIFT SOUTH AND EAST AS THE EXITING SYSTEM MOVES AWAY. ONCE AGAIN THE FAR SOUTH AND SOUTHWEST WILL HAVE THE BEST CHANCE FOR LIGHT PRECIPITATION. CLEARING WILL ALSO BEGIN WITH MOST OF THE NORTH HALF GETTING A LOT OF SUNSHINE BY THE MIDDLE OF THE DAY. COULD BE QUITE A GRADIENT WITH THE HIGH TEMPERATURES WITH THE NORTH THE WARMEST AS IT SEES THE MOST SUN. LINGERING SPOTTY PRECIPITATION SHOULD END BY LATE IN THE EVENING. DEPENDING ON HOW FAST IT CLEARS...TEMPERATURES COULD GET QUITE CHILLY WITH A VERY LIGHT WIND FIELD IN PLACE. TUESDAY/TUESDAY NIGHT...UPPER RIDGE AND NORTHERLY FLOW MOVE INTO THE AREA DURING THIS PERIOD. THIS SHOULD ALLOW FOR A DECENT AMOUNT OF SUN. ONE THING THAT COULD SPOIL THAT WILL BE A LEFT FRONT QUADRANT THAT MOVES IN AND SPREADS SOME CLOUDS INTO THE NORTHERN HALF OF THE AREA. ECMWF IS PRODUCING SOME LIGHT QPF. HOWEVER...THERE IS NO INSTABILITY AND A RATHER DEEP DRY LAYER. SO IT SHOULD STAY DRY. TEMPERATURES SHOULD WARM DUE TO SUNSHINE BUT WILL BE TEMPERED BY THE UNFAVORABLE SURFACE WIND FIELD. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 419 AM MDT SUN APR 26 2015 A RIDGE WILL CONTINUE BUILDING INTO THE PLAINS ON WEDNESDAY AS ANOTHER SYSTEM MOVES IN OVER THE PACIFIC NORTHWEST. DRY CONDITIONS ARE EXPECTED TO LAST THROUGH FRIDAY MORNING AS THE RIDGE PUSHES FURTHER EAST. PRECIP CHANCES MOVE INTO THE WESTERN CWA FRIDAY AFTERNOON AS THE PAC NW TROUGH MOVES INTO THE ROCKIES AND SWRLY UPPER LEVEL FLOW DEVELOPS. SLIGHT CHANCE OF PRECIP IS KEPT THROUGH THE END OF THE PERIOD FOR THE FORECAST AREA WITH SHORTWAVES POSSIBLY GENERATING SHOWERS AND THUNDERSTORMS AS THE TROUGH MOVES INTO THE PLAINS. WARMER TEMPERATURES ARE EXPECTED DURING THIS PERIOD WITH HIGHS IN THE 70S. READINGS IN THE LOW 80S ARE POSSIBLE BY THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1130 AM MDT SUN APR 26 2015 FOR KGLD...THRU 12Z MONDAY CEILINGS WILL RANGE FROM OVC002-007 IN DRIZZLE AND FOG THAT DROPS VISIBILITY IN A 2-6 MILE RANGE. AFT 12Z MONDAY...MVFR CONDITIONS WITH OVC015 AND VCSH. WINDS ENE THRU FORECAST PERIOD 10-20KTS...HIGHEST BEFORE 00Z MONDAY...AND AFTER 12Z MONDAY. FOR KMCK...SLOW INCREASING TREND IN CEILINGS HEIGHTS THRU FORECAST PERIOD. LOOKING FOR MVFR/IFR MIX THRU 03Z...THEN TRENDING TO MVFR BKN030 THRU 09Z...THEN VFR AT BKN035. SOME DRIZZLE THROUGH 22Z WITH 5SM IN FOG. WINDS ENE 10-20KTS...MOST GUSTS NEAR 20KTS THROUGH 22Z THIS AFTERNOON. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...JN SHORT TERM...BULLER LONG TERM...JBH AVIATION...JN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
317 PM EDT SUN APR 26 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 317 PM EDT SUN APR 26 2015 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP CYC FLOW ARND CLOSED LO CENTERED OVER NOVA SCOTIA EXTENDING W INTO THE UPR LKS AND DOWNSTREAM OF UPR RDG IN THE PLAINS. SHRTWV EMBEDDED WITHIN THE UPR TROF IS NEAR THE SOO AND SHIFTING TO THE SSW IN THE NE UPR FLOW ARND THE CLOSED LO. THIS DISTURBANCE IS BRINGING SOME CLDS TO ERN UPR MI...BUT ANY ACCOMPANYING PCPN IS ON TRACK TO REMAIN TO THE E OF THE CWA. THERE IS ANOTHER SHRTWV OVER WRN QUEBEC ROTATING TO THE WSW ARND THE CLOSED LO. 12Z RAOB FM MOOSONEE ONTARIO SHOWED DEEP SATURATION. UNDER THE TWO SHRTWVS NOTED TO THE E...THERE ARE PLENTY OF LO CLDS E AND NE OF THE SOO ASSOCIATED WITH THIS DEEPER MSTR. DRYNESS OF THE AIRMASS FARTHER TO THE W AS SHOWN ON THE 12Z GRB AND INL RAOBS /12Z PWAT AT THOSE LOCATIONS WAS ABOUT 0.25 INCH AND AS LITTLE AS 50 PCT OF NORMAL/ IS MAINTAINING MOSUNNY SKIES OVER MOST OF THE CWA. TEMPS HAVE RISEN INTO THE 50S AWAY FM THE MODERATING INFLUENCE OF LK SUP...BUT READINGS REMAIN NEAR 40 ALONG THE CHILLY LK SUP SHORE. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POTENTIAL FOR AREA OF LO CLDS TO THE NE TO IMPACT UPR MI AND IMPACT ON TEMPS. TNGT...AS SECOND SHRTWV NOW OVER WRN QUEBEC ROTATES SWWD AND OVER FAR ERN UPR MI...THE LLVL FLOW IS FCST TO VEER MORE TO THE NE AND ADVECT THE MORE COPIOUS LLVL MSTR INTO THE UPR LKS. IN CONCERT WITH NOCTURNAL COOLING THAT WL END DEEP MIXING...EXPECT BKN-OVC LO CLDS TO DVLP OVER MAINLY THE NCENTRAL AND ERN CWA AS INDICATED BY CURRENT FCST. ALTHOUGH THE DPVA/DEEP LYR QVECTOR CNVGC AHEAD OF THIS SHRTWV ARE FCST TO BRUSH THE ERN CWA...THE BULK OF THE MODELS INDICATE THE PCPN WL REMAIN TO THE E OF THAT AREA WITH THE MID LVLS REMAINING TOO DRY. SEVERAL OF THE HIER RES MODELS DO GENERATE SOME LGT PCPN OVER MAINLY THE HIER TERRAIN OF THE NCENTRAL...WHERE THE UPSLOPE FLOW WL BE MAXIMIZED. OPTED TO INCLUDE A MENTION OF SOME DRIZZLE/FLURRIES IN THESE AREAS LATE TNGT. EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR FAR W...WHICH WL BE FARTHER FM THE INCOMING HIER LLVL MSTR AND WHERE DOWNSLOPE...MORE DIFFLUENT FLOW NEAR SFC HI PRES RDG AXIS WL RESTRICT THE POTENTIAL FOR LO CLDS THAT WOULD ARRIVE LATER. MON...WITH DAYTIME HEATING AND FCST LOWERING SUBSIDENCE INVRN SHOWN ON FCST SDNGS...EXPECT THE LO CLDS TO GRADUALLY MIX OUT. THIS PROCESS WL BE SLOWEST OVER THE NCENTRAL AND E. H85 TEMPS WL BE CLOSE TO 0C...SO MAX TEMPS SHOULD RISE INTO THE 50S OVER THE INTERIOR W AND SCENTRAL WITH DEEP MIXING. BUT HI TEMPS WL REMAIN CLOSER TO THE LO END OF GUIDANCE OVER THE NCENTRAL AND E WITH MORE LO CLDS/LK MODERATION IN PERSISTENT LLVL N FLOW. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 317 PM EDT SUN APR 26 2015 A DRY WEATHER PATTERN IS EXPECTED MOST OF THE WEEK AS HIGH PRESSURE IS DOMINANT FACTOR. UPPER LEVEL PATTERN VARIABLE...STARTING OUT WITH A RIDGE ALOFT UPSTREAM OF LARGE UPPER LOW MOVING OFF THE EASTERN CANADA AND NEW ENGLAND. STRONG JET SURGING ACROSS WESTERN CANADA BRINGS SHORTWAVE TROUGH OVER SCNTRL CANADA ON MONDAY AND FM NORTHERN ONTARIO TO THE WESTERN GREAT LAKES TUESDAY INTO WEDNESDAY. PRIMARY WAVE SPLITS MONDAY NIGHT INTO TUESDAY AS IT ENCOUNTERS THE LINGERING RIDGING FM THE WESTERN GREAT LAKES TO NORTHERN QUEBEC. EXPECT DRY WEATHER TUESDAY AND TUESDAY NIGHT. 00Z ECMWF SHOWED SHORTWAVE DIVING SSE ACROSS UPR LAKES ON WEDNESDAY WITH ASSOCIATED MID-LEVEL Q-VECTOR CONVERGENCE AND LIFT. THAT RUN OF ECMWF ALSO FORECASTED SUFFICIENT H85-H7 RH TO GENERATE QPF OVER MAINLY EASTERN SECTIONS WEDNESDAY EVENING. GFS AND GEM-NH AND NOW THE 12Z ECMWF NOT AS BULLISH THOUGH...KEEPING STRONGEST FORCING TO THE EAST. WILL NOT SHOW MORE THAN SLIGHT CHANCES FAR EAST AS THE WAVE MOVES THROUGH LATE WEDNESDAY INTO WEDNESDAY NIGHT. THERMAL TROUGH WILL RESULT IN CHILLY TEMPS ON WEDNESDAY...ESPECIALLY WITH NORTHERLY GRADIENT WINDS NEAR LK SUPERIOR. TEMPS MAY STILL TOUCH 60 DEGREES OVER INLAND AREAS NEAR WI BORDER. SHORTWAVE SLIDES EAST BY THURSDAY PAVING THE WAY FOR RIDGING TO EXPAND FM CNTRL PLAINS TO SCNTRL CANADA TOWARD WESTERN GREAT LAKES. AS THE SFC...HIGH PRESSURE WILL EXPAND ACROSS THE WESTERN GREAT LAKES. THURSDAY APPEARS TO BE MORE OF A LAKE BREEZE DAY AT LEAST WEST...SO COOLING THERE WILL NOT BE AS EXPANSIVE AS WEDNESDAY. ENOUGH GRADIENT NORTH WINDS EAST TO KEEP ANY LK MICHIGAN LAKE BREEZE FROM DEVELOPING. DUE TO DEEPER MIXING...EXPECT HIGHS INLAND WEST TO REACH LOW-MID 60S. SHOWED LOWEST DWPNTS/RH OVER INTERIOR WEST BUT ALSO ALONG LK MICHIGAN WHERE PERSISTENT NORTH WINDS PROVIDE DOWNSLOPE DRYING. MORE STRONG JET ENERGY PUSHING ACROSS WESTERN CANADA WILL PROPEL ANOTHER STRONG SHORTWAVE OVER SCNTRL CANADA AND NORTHERN PLAINS THURSDAY NIGHT INTO FRIDAY...THEN OVER NORTHERN ONTARIO AND THE UPPER GREAT LAKES BY FRIDAY NIGHT. UNLIKE THE WAVE EARLIER IN THE WEEK...WAVE HOLDS TOGETHER WHILE PRESSING EAST AND THERE IS DECENT MOISTURE ADVECTION ALONG ASSOCIATED SFC-H85 TROUGH SWINGING TOWARD UPPER GREAT LAKES. AFTER A WARM AND DRY DAY FOR FRIDAY WITH SOME TEMPS REACHING LOWER 70S...SOME SHOWERS SHOULD SWING OVER THE CWA LATE FRIDAY INTO FRIDAY EVENING...BUT DESPITE THE WARMTH AHEAD OF THE SYSTEM...THERE IS NOT HIGH ENOUGH H85 THETA-E ADVECTION OR FORECAST INSTABILITY TO PUT ANY TSRA IN ALONG THE TROUGH. SEEMS MODELS ARE LOCKING ONTO THIS IDEA OF SOME SHRA THOUGH WITH SIMILAR TIMING IN TROUGH PASSAGE. CARRIED LOW CHANCES FROM WEST TO EAST LATE FRIDAY INTO FRIDAY NIGHT. INTO NEXT WEEKEND...GFS QUICKER WITH PRIMARY SHORTWAVE TROUGH MOVING OVER SCNTRL CANADA...SO IT SHOWS ANOTHER SFC TROUGH AND WARM/MOIST ADVECTION/QPF INTO WESTERN LAKES AS EARLY AS SATURDAY NIGHT. 00Z ECMWF APPEARED MORE REASONABLE BY SHOWING SLOWER PROGRESSION OF MAIN TROUGHING AND DEVELOPING A SFC WARM FRONT FM NORTHERN PLAINS TO UPPER MISSISSIPPI RIVER VALLEY ON LEADING EDGE OF VERY WARM AIR. 00Z ECMWF WOULD INDICATE DUE TO THE MOISTURE ADVECTION ALOFT TO THE NORTH OF WARM FRONT COULD SEE CHANCES OF ELEVATED SHOWERS SPREAD TOWARD UPPER GREAT LAKES ON SUNDAY OR SUNDAY NIGHT. BETTER CHANCE FOR TSRA WOULD BE CLOSER...BUT PROBABLY WOULD SET UP JUST SOUTH OF UPPER LAKES CLOSER TO GRADIENT OF 1-2K J/KG MUCAPE AREA FM CNTRL PLAINS TO UPPER MISSISSIPPI RIVER VALLEY. LATEST ECMWF IS A MORE AGGRESSIVE IN PLOWING MOISTURE AND WARM AIR ADVECTION ALOFT INTO UPR LAKES SATURDAY NIGHT INTO SUNDAY. LEANED ON CONSENSUS BUT DID INCREASE POPS SLIGHTLY ON SUNDAY GIVEN THAT TREND. DID NOT PUT TSRA IN FORECAST YET THOUGH THOUGH BASED ON H85 THETA-E AND GRADIENT OF MUCAPE FM THE 12Z ECMWF IT COULD OCCUR OVER THE AREA. GIVEN H85 TEMPS WARMING ABOVE +10C...TEMPS BOTH SATURDAY AND SUNDAY COULD RISE AT LEAST INTO THE LOW 70S MOST AREAS AWAY FM ANY COOLING FM THE LAKES. BASED ON 12Z RUNS OF MODELS...THINK BEST CHANCE FOR WARMING WILL BE ON SATURDAY AFTN IN WAKE OF FRIDAY NIGHT SYSTEM WITH WESTERLY LOW-LEVEL WINDS AND INCREASING SUNSHINE/DRYING. TEMPS ON SUNDAY WILL DEPEND ON SHRA AND CLOUD COVERAGE. LEANED ON CONSENSUS TEMPS /HIGHS MAINLY 60S/ MORE THAN SATURDAY WITH BETTER CHANCES OF RAIN BY THAT POINT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 132 PM EDT SUN APR 26 2015 AS MORE LLVL MSTR ARRIVES FM THE NE TNGT IN THE PRESENCE OF NOCTURNAL COOLING...EXPECT LO CLDS TO IMPACT MAINLY CMX AND ESPECIALLY SAW...WHERE THE EXPECTED NNE WIND WL HAVE THE SHARPER UPSLOPE COMPONENT. IFR CIGS SHOULD OCCUR AT SAW FOR A NUMBER OF HRS LATE TNGT THRU MUCH OF MON MRNG. IFR CONDITIONS AT CMX WL ALSO BE PSBL...BUT MAINTAINED PREVIOUS FCST LO MVFR RANGE CONDITIONS FOR NOW. IWD MAY ALSO SEE SOME LO CLDS/MVFR CIGS...BUT DOWNSLOPE WIND COMPONENT AND LOCATION OF WRN EDGE OF THE MORE SGNFT MSTR JUSTIFY ONLY A SCT SKY FCST ATTM. SAW WL SEE THE SLOWEST IMPROVEMENT ON MON...WITH VFR CONDITIONS NOT LIKELY THERE UNTIL AFTER THE END OF THIS FCST PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 317 PM EDT SUN APR 26 2015 EXPECT N WINDS UP TO 20 KTS INTO MON...STRONGEST OVER THE E HALF OF THE LAKE UNDER SHARPER PRES GRADIENT BETWEEN HI PRES RIDGE ALIGNED FROM NW ONTARIO THRU THE UPPER MS RIVER VALLEY. AS THE HI PRES RIDGE DRIFTS TO THE E LATER ON MON THRU TUE...WINDS WILL DIMINISH UNDER 15 KTS. A LO PRES TROF WILL CROSS THE UPPER LAKES TUE NIGHT AND THEN GIVE WAY TO ANOTHER HI PRES RIDGE THRU THU. SINCE THE PRES GRADIENT WILL REMAIN ON THE WEAK SIDE...WINDS SHOULD STAY BELOW 15 KTS. ALTHOUGH THE PRES GRADIENT WILL TIGHTEN UP A BIT ON FRI AHEAD OF ANOTHER LO PRES TROF...HI STABILITY OVER THE CHILLY LAKE WATERS SHOULD HOLDS WINDS UNDER 15 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
132 PM EDT SUN APR 26 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 507 AM EDT SUN APR 26 2015 WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW MID LEVEL RIDGE EXTENDING FROM THE NRN PLAINS TO SRN HUDSON BAY. TO THE SE...A MID LEVEL LOW IS CENTERED OFF THE CANADIAN MARITIMES WITH ITS BROAD CIRCULATION EXTENDING BACK TO THE UPPER LAKES. TWO SHORTWAVES OF NOTE ARE SWINGING W IN THE MID LEVEL LOW CIRCULATION ACROSS SE CANADA. THE FIRST IS S OF JAMES BAY AND THE SECOND IS N OF MAINE. AT THE SFC... THE MID LEVEL RIDGE IS SUPPORTING HIGH PRES RIDGING S FROM HUDSON BAY INTO THE UPPER MISSISSIPPI VALLEY. UNDER DRY AIR MASS PER 00Z REGIONAL SOUNDINGS...CLEAR SKIES CONTINUE TO PREVAIL ACROSS THE FCST AREA EARLY THIS MORNING. TO THE NE...FIRST SHORTWAVE S OF JAMES IS HELPING TO SPREAD SCT-BKN CLOUDS TOWARD LAKE SUPERIOR. THE FIRST SHORTWAVE S OF JAMES BAY WILL ROTATE INTO NRN LWR MI THIS AFTN/EVENING...SPREADING SOME CLOUDINESS INTO THE ERN FCST AREA TODAY. TRENDS IN THE MODELS SHOW A BACKING OFF ON THE POTENTIAL CLOUD COVER WHICH SEEMS REASONABLE BASED ON OVERNIGHT SATELLITE IMAGERY. FCST THUS REFLECTS A MORE OPTIMISTIC SKY CONDITION FOR CNTRL UPPER MI TODAY. MAY STILL SEE SOME PERIODS OF MOSTLY CLOUDY CONDITIONS OVER THE ERN FCST AREA THIS AFTN...ESPECIALLY LATE. AS FOR TEMPS...RATHER BRISK GRADIENT FLOW OFF LAKE SUPERIOR WILL HOLD TEMPS TO THE LOWER 40S NEAR LAKE SUPERIOR TODAY. MOST LAKESIDE LOCATIONS FROM THE KEWEENAW EASTWARD WILL NOT GET OUT OF THE 30S. WELL INLAND...NAM/GFS FCST SOUNDINGS AND PROJECTED MIXING HEIGHTS SUGGEST HIGH TEMPS MAY STRUGGLE TO REACH 50F. THERE MAY BE SOME LWR 50S TOWARD THE MI/WI BORDER FROM MENOMINEE COUNTY TO IRON COUNTY. TONIGHT...SECOND SHORTWAVE NOW N OF MAINE WILL FOLLOW THE SAME TRACK AS THE FIRST AND SHOULD REACH NRN LWR MI LATE TONIGHT. MODELS ARE AGGRESSIVE IN SWINGING MOISTURE BACK INTO UPPER MI TONIGHT WITH THIS FEATURE. OF PARTICULAR NOTE IS THE LOW-LEVEL MOISTURE THE NAM/GFS SHOW. LOOKING TO THE NE...LOW CIGS ARE NOTED IN AND AROUND JAMES BAY AND EASTWARD EARLY THIS MORNING. WITH THIS MOISTURE PUSHING SW INTO THE AREA DURING THE NIGHT WHEN DAYTIME HEATING IS ABSENT TO HELP LIFT OR MIX MOISTURE OUT...IT LOOKS FAIRLY LIKELY THAT LOW CLOUDS WILL DEVELOP/EXPAND TONIGHT...ESPECIALLY LATE...OVER AT LEAST THE NCNTRL AND E...AIDED BY UPSLOPE FLOW. NAM FCST SOUNDINGS EVEN SUGGEST THE POTENTIAL FOR SOME -DZ/-FZDZ WHERE STRONGEST UPSLOPE OCCURS. WILL BE SOMETHING TO TAKE A LOOK AT AGAIN IN LATER MODEL RUNS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 400 AM EDT SUN APR 26 2015 LINGERING LOW LEVEL MOISTURE AND COOLER AIRMASS BEHIND A SHORTWAVE TROUGH THAT MOVED THROUGH SUN NIGHT WILL LEAD TO CLOUD COVER EARLY MON OVER ESPECIALLY THE CENTRAL AND ERN CWA. THE CLOUD COVER WILL SLOWLY DIMINISH AS THE SFC RIDGE MOVES BACK IN FROM THE W AS WELL AS THE APPROACH OF AN UPPER RIDGE. CAN NOT COMPLETELY RULE OUT SOME LIGHT DRIZZLE IN UPSLOPE AREAS OF NCENTRAL UPPER MI...BUT NOT ENOUGH CONFIDENCE TO INCLUDE IN THE FORECAST. INTERIOR W SHOULD SEE HIGHS APPROACH 60F ON MON...WHILE LAKESHORE AND ERN AREAS ARE QUITE A BIT COOLER WITH HIGHS IN THE UPPER 30S TO THE UPPER 40S. A COUPLE OF ROUNDS OF SHORTWAVE ENERGY WILL BREAK DOWN THE RIDGE TUE EVENING AND AGAIN ON WED...WITH MODELS CURRENTLY SHOWING THE STRONGER SHORTWAVE ON WED. MODELS HAVE NOT SHOWN GOOD CONTINUITY WITH THESE FEATURES...SO CONFIDENCE IN EXACT DETAILS IS LOW. HOWEVER...MODEL DO GENERALLY AGREE THAT MOISTURE WILL BE LIMITED ENOUGH TO KEEP ANY SIGNIFICANT PRECIP FROM OCCURING. TUE WILL BE WARMER THAN MON WITH HIGHS IN THE 50S AND 60S AS THE AIRMASS WILL BE WARMER AND THE SHORTWAVE/CLOUD COVER DOES NOT ARRIVE UNTIL LATER IN THE DAY. WED COULD SEE A SIGNIFICANT COOLER AIRMASS DEPENDING ON DETAILS WITH THE SHORTWAVE...POSSIBLY RESULTING IN HIGH TEMPS IN THE 40S TO MID 50S. UPPER RIDGING REPLACES THE SHORTWAVE ENERGY THU INTO FRI. MODELS HAVE BEEN STRUGGLING WITH CONTINUITY IN THE STRENGTH OF THE RIDGE...LIMITED CONFIDENCE SOME. HIGHS ON THU WILL BE IN THE 50S TO MID 60S...WITH SIGNIFICANTLY WARMER HIGHS IN THE 60S TO LOW 70S ON FRI. MODEL DISAGREEMENT AND DISCONTINUITY CERTAINLY CONTINUE AND INCREASE ON SAT AS MODELS VARY VASTLY IN THE STRENGTH AND PLACEMENT OF UPPER LEVEL ENERGY OVER CENTRAL CANADA. MODELS SHOW SOME SHORTWAVE ENERGY MOVING ACROSS THE CWA WITH A WEAK SFC TROUGH LATE FRI AND FRI NIGHT...WHICH COULD PRODUCE CONVECTION ACROSS THE CWA. WILL CONTINUE SHOWING SLIGHT CHANCE POPS GIVEN UNCERTAINTY. ADDITIONAL DIFFERENCE BETWEEN MODELS /ALSO TIED TO UNCERTAINTIES WITH THE CENTRAL CANADA ENERGY/ WITH TEMPS ON SAT. THE 12Z/25 ECMWF BRINGS AN AMPLIFIED UPPER RIDGE TO JUST W OF THE CWA BY 00Z SUN WHILE THE 00Z/26 GFS HAS AN UPPER TROUGH WHERE THE ECMWF HAS THE RIDGE. AIRMASS WILL BE A LOT WARMER UNDER THE ECMWF SOLUTION WITH 850MB TEMPS OF 12C BY 00Z SUN WHILE THE GFS IS AT 8C. WHILE POTENTIAL FOR MUCH WARMER TEMPS EXISTS...CONFIDENCE IS LOW SO WILL CONTINUE WITH A CONSENSUS APPROACH WITH HIGHS INT HE 60S AND 70S AWAY FROM THE IMMEDIATE LAKESHORE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 132 PM EDT SUN APR 26 2015 AS MORE LLVL MSTR ARRIVES FM THE NE TNGT IN THE PRESENCE OF NOCTURNAL COOLING...EXPECT LO CLDS TO IMPACT MAINLY CMX AND ESPECIALLY SAW...WHERE THE EXPECTED NNE WIND WL HAVE THE SHARPER UPSLOPE COMPONENT. IFR CIGS SHOULD OCCUR AT SAW FOR A NUMBER OF HRS LATE TNGT THRU MUCH OF MON MRNG. IFR CONDITIONS AT CMX WL ALSO BE PSBL...BUT MAINTAINED PREVIOUS FCST LO MVFR RANGE CONDITIONS FOR NOW. IWD MAY ALSO SEE SOME LO CLDS/MVFR CIGS...BUT DOWNSLOPE WIND COMPONENT AND LOCATION OF WRN EDGE OF THE MORE SGNFT MSTR JUSTIFY ONLY A SCT SKY FCST ATTM. SAW WL SEE THE SLOWEST IMPROVEMENT ON MON...WITH VFR CONDITIONS NOT LIKELY THERE UNTIL AFTER THE END OF THIS FCST PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 507 AM EDT SUN APR 26 2015 WITH SFC HIGH PRES RIDGING S THRU WRN LAKE SUPERIOR TODAY THRU MON...WINDS WILL BE LIGHTEST OVER WRN LAKE SUPERIOR...MOSTLY UNDER 15KT. OVER THE E...WINDS WILL OCCASIONALLY GUST TO 20-25KT. THE RIDGE WILL WEAKEN TUE AND GIVE WAY TO LOW PRES TROF PASSAGE TUE NIGHT. IN ITS WAKE...ANOTHER HIGH PRES WILL RIDGE S FROM HUDSON BAY INTO THE UPPER GREAT LAKES WED/THU. WITH PRES GRADIENT ON THE WEAK SIDE...WINDS TUE THRU THU SHOULD BE UNDER 15KT ACROSS LAKE SUPERIOR THOUGH THERE MAY BE SOME STRONGER WINDS ON WED AS THE HIGH BEGINS RIDGING S INTO THE UPPER LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...KC MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1115 AM CDT SUN APR 26 2015 .UPDATED FOR 18Z AVIATION DISCUSSION BELOW... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 349 AM CDT SUN APR 26 2015 A VERY PLEASANT DAY IS AHEAD WITH A RIDGE OF HIGH PRESSURE HOLDING STEADY FROM WESTERN ONTARIO THROUGH MINNESOTA AND WISCONSIN. THE SKY WILL BE MAINLY CLEAR TODAY AS WELL AS TONIGHT ALONG WITH A LIGHT NORTHEAST TO EAST WIND. HIGHS THIS AFTERNOON WILL BE SIMILAR THOSE ON SATURDAY WITH LOWER TO MIDDLE 60S FORECAST...WHICH IS VERY CLOSE TO THE SEASONAL NORMAL. THE FORECAST HIGHS TODAY LINE UP WELL WITH MIX-DOWN FROM THE NAM AT 825MB ALONG WITH A SLIGHT SUPER. THE REAL CHALLENGE TODAY IS HOW LOW WILL DEW POINTS DROP... ESPECIALLY ACROSS CENTRAL MN...AND THE CORRESPONDING AFTERNOON MINIMUM HUMIDITY. THE LOW LEVEL NORTHEAST FLOW BROUGHT DEW POINTS IN THE SINGLE DIGITS AND LOWER TEENS INTO NORTHEAST MN SATURDAY EVENING. DEW POINTS NEAR 20 DEGREES ARE NOW PREVALENT ACROSS CENTRAL MN EARLY THIS MORNING. THE NAM AND RAP HAVE A GOOD HANDLE ON THE SITUATION AND LOWER DEW POINTS TO NEAR 15 DEGREES ACROSS MUCH OF CENTRAL MN THIS AFTERNOON WITH AROUND 20 HERE IN THE TWIN CITIES AND WEST CENTRAL WI. THIS RESULTS IN NEAR 15 PERCENT MINIMUM HUMIDITY THIS AFTERNOON ACROSS MUCH OF CENTRAL MN WITH 20 PERCENT HERE IN THE CITIES AND WEST CENTRAL WI. SOUTHERN AREAS OF MN BOTTOM OUT AROUND 25 PERCENT. FORTUNATELY...THE NORTHEAST TO EAST WINDS ARE EXPECTED TO STAY AT OR BELOW 10 MPH THIS AFTERNOON KEEPING THE FIRE THREAT MAINLY IN THE LIMITED RANGE WITH ELEVATED INDICATED ACROSS WEST CENTRAL MINNESOTA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 349 AM CDT SUN APR 26 2015 MILD TEMPERATURES STILL LOOK ON TAP FOR NEXT WEEK...WITH TWO MOISTURE STARVED FRONTS TRAVERSING THE UPPER MS RIVER VALLEY MONDAY NIGHT/TUESDAY AND AGAIN ON FRIDAY. THE TROUBLE MAKER FOR MODEL AGREEMENT THROUGH THE EXTENDED CONTINUES TO BE THE EVOLUTION OF THE DEEP CLOSED H5 LOW OVER NEW ENGLAND NEXT WEEK. MODEL AGREEMENT IS NOT REALLY ALL THAT BAD UNTIL WE GET TO THURSDAY...WHEN THE GFS STARTS TO BECOME MORE AGGRESSIVE WITH PUSHING THIS LOW OUT INTO THE NORTH ATLANTIC...WHICH ALLOWS IT TO BECOME CONSIDERABLY MORE PROGRESSIVE THAN THE GEM/ECMWF WITH THE FLOW ACROSS THE CONUS TO END THE WORK WORK GOING INTO NEXT WEEKEND. FOR MODEL PREFERENCES...WENT WITH A FAIRLY EQUAL BLEND THROUGH THURSDAY...LEANING MORE TOWARD THE LESS PROGRESSIVE ECMWF SOLUTION FOR FRIDAY INTO NEXT WEEKEND. THE LONG TERM WILL START OFF WITH A PICTURE PERFECT DAY ON MONDAY...WITH HIGHS IN THE UPPER 60S/LOWER 70S...SUNNY SKIES AND LIGHT WINDS. MONDAY NIGHT WILL FEATURE A SHORTWAVE MOVING INTO NORTHERN MN...WITH A WEAK COLD FRONT MOVING INTO THE AREA AS WELL. PRECIP POTENTIAL STILL DOES NOT LOOK ALL THAT GREAT FOR THIS FRONT...WITH THE UPPER LOW OVER TEXAS KEEPING ANY MEANINGFUL MOISTURE WELL OF TO OUR SOUTH...WITH CONVERGENCE ALONG THE BOUNDARY LOOKING WEAK AS WELL. THE ECMWF CONTINUES TO BE AN OUTLIER WITH THE STRENGTH OF THIS WAVE AND THE AMOUNT OF PRECIP IT GENERATES AND CONTINUED THE TREND OF FAVORING A DRIER SOLUTION FOR THIS FRONT...WITH JUST SLIGHT CHANCE/LOW CHANCE POPS MENTIONED. WEDNESDAY AND THURSDAY WILL FEATURE ANOTHER DRY RIDGE OF HIGH PRESSURE MOVING THROUGH. ONLY CHANGE MADE TO BLENDED FORECAST HERE WAS TO LOWER DEWPOINTS SOME BOTH DAYS TO ACCOUNT FOR THE MIXING POTENTIAL. ALSO BLENDED IN SOME BIAS CORRECTED NUMBERS INTO THE HIGHS BOTH DAYS TO BOOST THEM BY A FEW DEGREES EACH DAY...WITH WIDESPREAD HIGHS IN THE 70S EXPECTED FOR WED/THU. NEXT ISSUE IN THE EXTENDED COMES FRIDAY WITH THE PASSAGE OF THE NEXT COLD FRONT. GIVEN THE DIFFERENCES IN THE HANDLING OF THE NEW ENGLAND H5 LOW MENTIONED IN THE SECOND PARAGRAPH...THE GFS IS QUITE A BIT FASTER WITH BRINGING THE FRONT THROUGH THAN THE ECMWF. THIS SPREAD IN THE FRONTS TIMING EXPLAINS THE NICE SMEARING OF SLIGHT CHANCE POPS ACROSS THE AREA ON FRIDAY. THIS FRONT DOES HAVE A COUPLE OF FACTORS THAT CAN GIVE ONE A LITTLE BIT MORE HOPE FOR SEEING PRECIP WITH THIS BOUNDARY AS OPPOSED TO THE ONE FOR MONDAY NIGHT. NUMBER ONE...THERE WILL BE NO UPPER LOW OVER TEXAS INTERCEPTING MOISTURE STREAMING NORTH. ALSO MAKING THE PRECIP POTENTIAL LOOK SLIGHTLY BETTER IS THAT THE LOW LEVEL CONVERGENCE LOOKS BETTER ON FRIDAY AND THIS FRONT ACTUALLY HAS SOME H85 FLOW AND MOISTURE TRANSPORT OUT AHEAD OF IT. STILL...THE AIRMASS IT WILL BE DISPLACING AGAIN LOOKS INCREDIBLY DRY AND WITH INSTABILITY LACKING...ANYTHING WE DO SEE LOOKS PRETTY LIGHT AT THIS POINT. AS FOR FIRE WEATHER CONCERNS NEXT WEEK...HUMIDITIES EACH AFTERNOON LOOK TO GET DOWN INTO THE 20S/30S. WINDS STILL LOOK LIGHT THOUGH THROUGH WEDNESDAY...BUT THURSDAY AND FRI WILL FEATURE STRONGER WINDS AND IF THE MOISTURE RETURN ENDS UP BEING RATHER LACKING...WE COULD HAVE FIRE WEATHER CONCERNS ONCE AGAIN. AT THIS POINT...THURSDAY LOOKS TO BE THE DAY THAT HAS THE GREATEST POTENTIAL TO GENERATE RED FLAG CONDITIONS AS OUR SE WINDS WILL BE EMANATING FROM A VERY DRY SFC RIDGE CENTERED OVER THE GREAT LAKES....WHILE FRIDAY AT THIS POINT LOOKS TO FEATURE HIGHER DEWPS WITH THE PASSING FRONT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1105 AM CDT SUN APR 26 2015 VFR/SKC THROUGH THE PERIOD AS A RIDGE OF HIGH PRESSURE MOVES EAST ACROSS WESTERN GREAT LAKES. LIGHT NE WINDS BECOMING SE OVER THE WESTERN PORTION OF HE AREA TONIGHT INTO MONDAY. KMSP.. WIND IS THE ONLY PROBLEM THIS PERIOD. SHOULD SEE A MORE NE COMPONENT DEVELOP WITH MIX THIS AFTERNOON...AND THEN LIGHT NORTH INTO MONDAY AFTERNOON. /OUTLOOK FOR KMSP/ MON NIGHT...VFR. WINDS N 5 KTS. TUE...VFR. SLGT CHC OF MRNG -SHRA. WINDS NW 5-10 KTS. WED...VFR. WIND N 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...RAH LONG TERM...MPG AVIATION...DWE
AREA FORECAST DISCUSSION
NWS TULSA OK
1135 AM CDT SUN APR 26 2015 ...UPDATE... .DISCUSSION... SURFACE ANALYSIS SHOWS A WARM FRONT DRAPED ACROSS NRN TX...JUST S OF THE RED RIVER WITH THE DRYLINE ACROSS WEST TX. OUR FORECAST AREA IS UNDER THE INFLUENCE OF ELY TO NELY LOW-LEVEL FLOW...WITH SOME HIGHER DEWPOINT POOLING NOTED ACROSS FAR SE OK. IN THE NEARER TERM...LOW CLOUDS ACROSS NE OK AND FAR NW AR ARE STARTING TO SHOW SIGNS OF LIFTING N AND MIXING OUT...AND EXPECT THIS TREND TO CONTINUE. WHILE THE HIGHEST RISK OF SEVERE WEATHER IS EXPECTED TO REMAIN FARTHER S ACROSS CENTRAL TX...WE`LL NEED TO KEEP AN EYE ON STORMS MAKING A RUN TOWARD SE OK BY THIS EVENING. LATEST 12Z NAM AND RECENT RUNS OF THE HRRR HAVE DELAYED THE ARRIVAL OF STORMS INTO OUR AREA A BIT...SO HAVE TWEAKED EVENING POPS ACCORDINGLY. && .PRELIMINARY POINT TEMPS/POPS... TUL 73 52 62 47 / 10 80 70 50 FSM 76 53 63 49 / 10 50 50 70 MLC 82 55 61 48 / 10 80 70 70 BVO 69 51 61 47 / 10 50 50 40 FYV 71 49 60 45 / 10 40 30 50 BYV 65 47 61 46 / 10 20 20 30 MKO 78 53 61 48 / 10 80 70 60 MIO 67 49 63 46 / 10 20 30 30 F10 77 53 59 48 / 10 80 70 70 HHW 83 56 65 50 / 10 70 70 80 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...18 LONG TERM....10
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
340 PM EDT SUN APR 26 2015 .SYNOPSIS... A SLOW MOVING UPPER LEVEL LOW OVER THE NORTHEASTERN UNITED STATES AND COOL AIR ALOFT WILL FAVOR UNSEASONABLY CHILLY TEMPERATURES WITH PERIODS OF SHOWERY WEATHER THROUGH THE END OF THIS MONTH. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... A SPRAWLING UPPER LOW OVER THE CANADIAN MARITIMES WILL CONTROL THE PATTERN FOR THE NEXT COUPLE OF DAYS AT LEAST. THE MAIN EFFECT WILL TO FUNNEL A SERIES OF UPPER SHORTWAVES DOWN OUT OF NEW YORK/EASTERN CANADA AND KEEP A FAIR AMOUNT OF CLOUDINESS AND THE CHANCE FOR SHOWERS IN THE FORECAST. THE FIRST SYSTEM CAN BE SEEN ON SATELLITE AS AN AREA OF CLOUDINESS DROPPING SOUTH INTO NRN PA. THE COARSER RESOLUTION MODELS CREATE SOME LIGHT QPF AND THE HRRR HINTS AT SOME SMALL CELLULAR ACTIVITY AT MAX HEATING. IT MAKES SENSE WITH THE COLD AIR ALOFT AND THE STRONG LATE APRIL SUN. I DON`T FEEL CONFIDENT IN MEASURING ANYWHERE HOWEVER SO WILL JUST KEEP THE MENTION OF ISOLATED SPRINKLES FOR NOW. THE SPRINKLES WILL VANISH WITH THE LOSS OF HEATING BUT UPSTREAM CLOUDINESS LOOKS DESTINED TO CONTINUE EDGING SOUTH OVERNIGHT INTO THE REGION. IT SHOULD REMAIN DRY HOWEVER UNDER A SUBTLE AREA OF WEAK UPPER RIDGING BETWEEN THE SYSTEM APPROACHING NOW AND A STRONGER SHORTWAVE SLATED FOR MONDAY. LOWS WILL RANGE FROM AROUND FREEZING OVER THE NW TO AROUND 40 IN THE SE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... MODELS AGREE IN BRINGING A RELATIVELY SHARP SHORTWAVE DOWN THROUGH THE EASTERN GR LAKES AND THROUGH THE AREA MONDAY. FORECAST LAPSE RATES AREN`T TERRIBLY IMPRESSIVE SO THE COVERAGE OF THE QPF MAY BE A BIT OVERDONE. THE SREF/GEFS HAVE NOTHING MORE THAN A SMALL CHANCE AND THAT LOOKS REASONABLE. WITH MARGINALLY CHILLY TEMPS IN THE LOW LEVELS...CAN`T RULE OUT SOME WET SNOWFLAKES IF THE SHOWERS MANAGE TO DEVELOP EARLY ENOUGH IN THE DAY MONDAY. NO ACCUMS ARE ANTICIPATED. HIGHS FROM THE UPPER 40S TO UPPER 50S WILL AVERAGE WELL BELOW NORMAL FOR THE END OF APRIL. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... ACTIVE NORTHERN AND SOUTHERN STREAM SPLIT FLOW PATTERN ACROSS NORTH AMERICA WILL KEEP THE REGION IN UPPER LEVEL TROFFINESS THROUGH MUCH OF THE COMING WEEK. THIS WILL SUPPORT COOLER THAN NORMAL...SHOWERY WEATHER. UPPER LEVEL RIDGING WILL MOVE EAST AND TRY TO PERSIST OVER THE EASTERN U.S. STARTING AROUND NEXT WEEKEND. EARLY THIS WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...SLOW MOVING SRN STREAM UPPER LOW WILL EMERGE INTO THE SERN TO MID ATLC STATES...POSSIBLY PHASING WITH A NRN STREAM WAVE. AT THIS POINT SIGNIFICANT PCPN LOOKS TO STAY SOUTH OF PA...THOUGH THE HIEST POPS OF THE PERIOD WILL BE FROM THIS SYSTEM ON THURSDAY. REGARDLESS...THURSDAY LOOKS TO BE A CLOUDY AND COOL DAY ACROSS THE COMMONWEALTH. AFFECTS OF THIS UPPER LOW SHOULD DIMINISH THROUGH FRIDAY INTO SATURDAY AND WITH RISING HEIGHTS THE START OF NEXT WEEK LOOKS WARMER AND DRIER...AT THIS POINT. && .AVIATION /20Z SUNDAY THROUGH FRIDAY/... WIDESPREAD VFR CONDITIONS WITH HIGH BASED CEILINGS OVER MAINLY NORTHERN AREAS AS A WEAK DISTURBANCE DROPS SOUTH OUT OF NY. CEILINGS WILL LOWER ACROSS THE NORTHERN MOUNTAINS AND LAUREL HIGHLANDS TONIGHT WITH MVFR CONDITIONS DEVELOPING BY MIDNIGHT IN THE VICINITY OF BRADFORD AND AFTER MIDNIGHT AT JOHNSTOWN. SCATTERED LIGHT RAIN/SNOW SHOWERS WILL ALSO MOVE INTO THESE AREAS FROM THE NORTH...PROBABLY NOT UNTIL SUNRISE OR SHORTLY AFTER. ELSEWHERE... CONDITIONS SHOULD REMAIN VFR THROUGH MONDAY. OUTLOOK... TUE...MAINLY VFR WITH SCT LIGHT RAIN SHOWERS. WED...NO SIG WX. THU-FRI...MVFR POSSIBLE IN SCATTERED RAIN SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
230 PM EDT SUN APR 26 2015 .SYNOPSIS... A SLOW MOVING UPPER LEVEL LOW OVER THE NORTHEASTERN UNITED STATES AND COOL AIR ALOFT WILL FAVOR UNSEASONABLY CHILLY TEMPERATURES WITH PERIODS OF SHOWERY WEATHER THROUGH THE END OF THIS MONTH. && .NEAR TERM /THROUGH TONIGHT/... A SPRAWLING UPPER LOW OVER THE CANADIAN MARITIMES WILL CONTROL THE PATTERN FOR THE NEXT COUPLE OF DAYS AT LEAST. THE MAIN EFFECT WILL TO FUNNEL A SERIES OF UPPER SHORTWAVES DOWN OUT OF NEW YORK/EASTERN CANADA AND KEEP A FAIR AMOUNT OF CLOUDINESS AND THE CHANCE FOR SHOWERS IN THE FORECAST. THE FIRST SYSTEM CAN BE SEEN ON SATELLITE AS AN AREA OF CLOUDINESS DROPPING SOUTH INTO NRN PA. THE COARSER RESOLUTION MODELS CREATE SOME LIGHT QPF AND THE HRRR HINTS AT SOME SMALL CELLULAR ACTIVITY AT MAX HEATING. IT MAKES SENSE WITH THE COLD AIR ALOFT AND THE STRONG LATE APRIL SUN. I DON`T FEEL CONFIDENT IN MEASURING ANYWHERE HOWEVER SO WILL JUST KEEP THE MENTION OF ISOLATED SPRINKLES FOR NOW. THE SPRINKLES WILL VANISH WITH THE LOSS OF HEATING BUT UPSTREAM CLOUDINESS LOOKS DESTINED TO CONTINUE EDGING SOUTH OVERNIGHT INTO THE REGION. IT SHOULD REMAIN DRY HOWEVER UNDER A SUBTLE AREA OF WEAK UPPER RIDGING BETWEEN THE SYSTEM APPROACHING NOW AND A STRONGER SHORTWAVE SLATED FOR MONDAY. LOWS WILL RANGE FROM AROUND FREEZING OVER THE NW TO AROUND 40 IN THE SE. && .SHORT TERM /MONDAY/... MODELS AGREE IN BRINGING A RELATIVELY SHARP SHORTWAVE DOWN THROUGH THE EASTERN GR LAKES AND THROUGH THE AREA MONDAY. FORECAST LAPSE RATES AREN`T TERRIBLY IMPRESSIVE SO THE COVERAGE OF THE QPF MAY BE A BIT OVERDONE. THE SREF/GEFS HAVE NOTHING MORE THAN A SMALL CHANCE AND THAT LOOKS REASONABLE. WITH MARGINALLY CHILLY TEMPS IN THE LOW LEVELS...CAN`T RULE OUT SOME WET SNOWFLAKES IF THE SHOWERS MANAGE TO DEVELOP EARLY ENOUGH IN THE DAY MONDAY. NO ACCUMS ARE ANTICIPATED. HIGHS FROM THE UPPER 40S TO UPPER 50S WILL AVERAGE WELL BELOW NORMAL FOR THE END OF APRIL. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... ACTIVE NORTHERN AND SOUTHERN STREAM SPLIT FLOW PATTERN ACROSS NORTH AMERICA WILL KEEP THE REGION IN UPPER LEVEL TROFFINESS THROUGH MUCH OF THE PERIOD. THE BLOCKED UP NRN STREAM...GENERALLY NW FLOW PATTERN OVER THE NORTHEAST WILL TEND TO SHUNT SRN STREAM SYSTEM TO THE SOUTH OF PA. EARLY NEXT WEEK A SHOT OF COOL UNSETTLED WEATHER ARRIVES AS A BACK DOOR COLD FRONT IS NUDGED SOUTHWARD ACROSS PA FROM AN UPPER LOW OVR NEW ENG. COOL TEMPS ALOFT ASSOC WITH UPPER LOW WILL LIKELY LEAD TO A GOOD DEAL OF DAYTIME CLOUDINESS AND SCT SHRA /ESP OVR THE MTNS/ MONDAY AND TUESDAY. BY MIDWEEK...THIS LOW FINALLY LIFTS OUT FOR GOOD..BUT DIGGING TROUGH FROM UPPER MIDWEST WILL EXTEND INTO THE SOUTHEAST U.S. BY LATE WEEK...COMBINED WITH A SOUTHERN STREAM SHORTWAVE LIFTING OUT OF THE S PLAINS TOWARD THE E COAST WILL BRING POSSIBILITY OF A DEVELOPING STORM SLIDING NORTHEASTWARD OFF THE EASTERN SEABOARD. TRACK/STRENGTH STILL QUITE UNCERTAIN...BUT AT THIS TIME LOOKS LIKE WE/LL BE BETWEEN THAT LOW PRESSURE AREA AND A HIGH OVER OHIO VALLEY...LIKELY KEEPING CLOUDS AND SCT SHOWERS AROUND AS TEMPS COOL BACK DOWN A BIT. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... WIDESPREAD VFR CONDITIONS WITH HIGH BASED CEILINGS OVER MAINLY NORTHERN AREAS AS A WEAK DISTURBANCE DROPS SOUTH OUT OF NY. CEILINGS WILL LOWER ACROSS THE NORTHERN MOUNTAINS AND LAUREL HIGHLANDS TONIGHT WITH MVFR CONDITIONS DEVELOPING BY MIDNIGHT IN THE VICINITY OF BRADFORD AND AFTER MIDNIGHT AT JOHNSTOWN. SCATTERED LIGHT RAIN/SNOW SHOWERS WILL ALSO MOVE INTO THESE AREAS FROM THE NORTH...PROBABLY NOT UNTIL SUNRISE OR SHORTLY AFTER. ELSEWHERE... CONDITIONS SHOULD REMAIN VFR THROUGH MONDAY. OUTLOOK... TUE...MAINLY VFR WITH SCT LIGHT RAIN SHOWERS. WED...NO SIG WX. THU-FRI...MVFR POSSIBLE IN SCATTERED RAIN SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
232 PM CDT SUN APR 26 2015 .DISCUSSION... WITH THE FOCUS OF THE FORECAST ON OUR SHORT TERM SEVERE WEATHER EVOLUTION...WILL KEEP THE DISCUSSION WITH REGARDS TO THE REMAINDER OF THE FORECAST BRIEF. THE DISCUSSION REGARDING THE EVOLUTION OF SEVERE STORMS TODAY AND TONIGHT REMAINS MOSTLY VALID STILL AT 2 PM...SO LEFT THE EARLY AFTERNOON UPDATE APPENDED BELOW. CHANGES FROM THE PREVIOUS UPDATE FOR TODAY...THE 18Z SUBJECTIVE SURFACE ANALYSIS INDICATED SURFACE CYCLOGENESIS WAS OCCURRING FARTHER NORTH THAN WHAT MODELS WERE INDICATING THIS MORNING. IF THE SURFACE LOW DOES NOT DEVELOP FARTHER SOUTH THIS AFTERNOON...THE PRIMARY INGREDIENTS FOR DISCRETE SUPERCELL THUNDERSTORMS MAY MOVE NORTH TOWARDS THE DFW METROPLEX THIS EVENING. THE SURFACE LOW IS EXPECTED TO DEEPEN THROUGH 00Z AND THE STRONGEST FORCING AND COMBINATION OF INGREDIENTS FOR SUPERCELLS WILL EXIST AT THAT TIME AS A RESULT. THE BEST WINDOW FOR DISCRETE SUPERCELL DEVELOPMENT WITHIN THE CWA...EAST OF THE SURFACE LOW STILL APPEARS TO BE ON TRACK FOR THE 5 PM TO 10 PM TIME FRAME. WILL CONTINUE TO WATCH THE EVOLUTION OF THE SURFACE LOW CLOSELY THIS AFTERNOON BECAUSE IF IT SETS UP FARTHER NORTH...THE BIGGEST THREAT FOR DISCRETE SUPERCELLS MAY MOVE AWAY FROM CENTRAL TEXAS AND TOWARDS THE DFW AREA. WILL HAVE TO JUST SEE WHAT HAPPENS AT THIS POINT. ANOTHER TORNADO WATCH IS LIKELY TO BE ISSUED LATE THIS AFTERNOON FOR MUCH OF NORTH AND CENTRAL TEXAS. WHILE THERE MAY NOT BE MANY STORMS...THE STORMS THAT DO DEVELOP ARE EXPECTED TO POSE A VERY HIGH THREAT OF SEVERE WEATHER. CONDITIONS STILL LOOK FAVORABLE FOR VERY LARGE HAIL...DAMAGING WINDS AND TORNADOES WHEREVER SUPERCELLS DEVELOP. A SQUALL LINE STILL LOOKS LIKELY TO DEVELOP ACROSS FAR SOUTHWEST OKLAHOMA OR ACROSS NORTHWEST TEXAS THIS EVENING. THIS SQUALL LINE STILL LOOKS LIKE IT WILL BE VERY ORGANIZED AND POSE A WIDESPREAD THREAT FOR DAMAGING WINDS AS IT MOVES SOUTHEAST ACROSS NORTH TEXAS LATE THIS EVENING AND OVERNIGHT. THE THREAT FOR FLOODING APPEARS TO BE UNCHANGED AT THIS TIME. WILL CONTINUE TO MONITOR THE THREAT FOR TRAINING STORMS THROUGH TONIGHT...HOWEVER CONFIDENCE IS NOT HIGH ENOUGH TO ISSUE A FLASH FLOOD WATCH AT THIS TIME. MONDAY...THUNDERSTORMS ARE VERY LIKELY ACROSS NORTH AND CENTRAL TEXAS MONDAY AFTERNOON...HOWEVER THE MODE AND OVERALL THREAT FOR SEVERE WEATHER IS VERY UNCERTAIN AT THIS TIME. IF A LARGE SQUALL LINE/DERECHO MOVES SOUTHEAST ACROSS NORTH TEXAS OVERNIGHT...IT MAY LEAVE A STRONG OUTFLOW BOUNDARY THAT WILL SIGNIFICANTLY ALTER THE THERMODYNAMIC ENVIRONMENT FOR MONDAY. UNTIL WE KNOW WHAT HAPPENS WITH STORMS THROUGH TONIGHT...IT WILL BE DIFFICULT TO IDENTIFY THE EXACT THREAT FOR SEVERE STORMS ON MONDAY. THERE WILL BE STRONG LIFT AS THE UPPER TROUGH PULLS EAST OVER THE SOUTHERN PLAINS...AND THERE WILL BE MOISTURE...SO OVERALL POPS ARE QUITE HIGH IN THE 50 TO 70 PERCENT CHANCE RANGE. THERE WILL PROBABLY BE A SUFFICIENT AMOUNT OF WIND SHEAR TO SUPPORT ORGANIZED STORMS TOMORROW AFTERNOON...HOWEVER CONDITIONS NEAR THE SURFACE MAY BE COOL AND CLOUD COVER MAY INHIBIT SURFACE BASED INSTABILITY FOR MUCH OF THE DAY TOMORROW. AT THIS TIME...THINK THAT THE LOCATIONS WITH THE BEST CHANCE FOR SEVERE STORMS TOMORROW AFTERNOON WILL TEND TO BE SOUTH OF INTERSTATE 20 AS THE OVERNIGHT SQUALL LINE IS MOST LIKELY ALONG AND NORTH OF I-20. WE WILL OBVIOUSLY HAVE TO REEVALUATE THE THERMODYNAMIC ENVIRONMENT TOMORROW MORNING AFTER THE SQUALL LINE HAS MOVED EAST OF THE CWA. TUESDAY...THE UPPER TROUGH/LOW IS EXPECTED TO BE OVER NORTH TEXAS...CENTERED OVER THE RED RIVER. THERE IS A CHANCE OF SEEING SOME STORMS RIGHT IN THE MIDDLE OF THE UPPER LOW AS THE COLD AIR ALOFT WILL HELP DESTABILIZE THE ENVIRONMENT...HOWEVER SKIES WILL LIKELY BE OVERCAST...SO SURFACE BASED STORMS APPEAR TO BE VERY UNLIKELY AT THIS TIME. SCATTERED ELEVATED SHOWERS AND THUNDERSTORMS ARE LIKELY NEAR THE CENTER OF THE UPPER LOW...SO HAVE THE HIGHEST POPS NEAR THE RED RIVER...AND LOWEST POPS ACROSS CENTRAL TEXAS ON TUESDAY. WEDNESDAY THROUGH FRIDAY...UPPER LEVEL RIDGING IS EXPECTED TO RESULT IN A WARMING TREND UNDER MOSTLY CLEAR SKIES FOR THE REMAINDER OF THE WEEK. CAVANAUGH && .PREVIOUS UPDATE /ISSUED AT 1239 PM/... MESOSCALE FORECAST UPDATE REGARDING THE FORECAST FOR SEVERE STORMS ACROSS NORTH AND CENTRAL TEXAS TODAY... 12Z UPPER AIR ANALYSIS SHOWED AN INTENSE UPPER LEVEL TROUGH LOCATED OVER THE SOUTHERN ARIZONA AND NEW MEXICO BORDER. 500 MB HEIGHT FALLS OF 6 TO 12 DM WERE OBSERVED DOWNSTREAM OF THIS UPPER TROUGH...AND THE MAGNITUDE OF THESE HEIGHT FALLS IS INDICATIVE OF STRONG LARGE SCALE FORCING FOR ASCENT TO THE EAST. AT THE 700 MB LEVEL...A PLUME OF STEEP MID-LEVEL LAPSE RATES WAS OBSERVED...WITH A TEMPERATURE DIFFERENCE IN THE 700 TO 500 MB LAYER OF 22 DEG C LOCATED SOUTHWEST OF NORTH AND CENTRAL TEXAS. TO THE SOUTHWEST OF THIS PLUME OF ENHANCED LAPSE RATES...A 50 KT MID-LEVEL JET CORE WAS OBSERVED OVER NORTHERN MEXICO. CLOSER TO THE SURFACE...AT THE 850 MB LEVEL...DEEP MOISTURE WAS ONLY OBSERVED OVER SOUTHWEST TEXAS WITH A DRYLINE SUBJECTIVELY ANALYZED NEAR THE TX/OK BORDER...EXTENDING SOUTHWEST OVER WEST CENTRAL TEXAS AND INTO NORTHERN MEXICO ABOUT 60 MILES WEST OF DEL RIO. A 15Z SURFACE ANALYSIS OBSERVED RICH MOISTURE IN PLACE ALONG THE TX GULF COAST WITH MID 70S DEW POINTS OBSERVED WEST AND SOUTHWEST OF HOUSTON. FOR TODAY...NEARLY ALL SHORT RANGE MODEL GUIDANCE INDICATES THAT A SURFACE LOW PRESSURE SYSTEM WILL INTENSIFY RAPIDLY THIS AFTERNOON OVER WEST CENTRAL TEXAS. MOST GUIDANCE SHOWS SURFACE PRESSURE FALLING AT A RATE OF 2-3 MB PER HOUR LEADING UP TO 00Z. AT 15Z...THE LOWEST SURFACE PRESSURE OVER THE SOUTHERN HIGH PLAINS WAS AROUND 1002 MB...MOST GUIDANCE INDICATES THE SURFACE LOW`S PRESSURE WILL FALL TO 993 TO 995 MB BY 00Z. THAT MAGNITUDE OF PRESSURE FALL ASSOCIATED WITH THE SURFACE LOW IS FAIRLY INTENSE...AND SHOULD RESULT IN A CONVERGENCE OF PARAMETERS THAT WILL SUPPORT A LOCALIZED SEVERE WEATHER OUTBREAK ACROSS THE REGION THIS AFTERNOON AND EVENING. ONE OF THE KEY FORECAST CHALLENGES TODAY WILL BE DETERMINING WHERE THE SURFACE LOW MOVES AS THE RELATIVE THREATS FOR SUPERCELLS AND TORNADOES WILL VARY DEPENDING ON THE EXACT POSITION OF THIS LOW LATER THIS AFTERNOON. THE 12Z NAM AND 16Z HRRR INDICATE THE SURFACE LOW WILL BE LOCATED JUST SOUTH OF INTERSTATE 20 AND JUST NORTH OF SAN ANGELO. IF THIS POSITION FOR THE SURFACE LOW IS CORRECT...THE THREAT FOR DISCRETE SUPERCELLS WOULD BE MAXIMIZED TO THE EAST OF THE SURFACE LOW...WHERE A TRIPLE POINT WOULD LIKELY SET UP. SUPERCELLS WOULD BE MOST LIKELY TO DEVELOP NEAR THIS TRIPLE POINT...AND THEN MOVE EAST IN THE RELATIVELY STRONG SOUTHWESTERLY FLOW ALOFT. STORMS APPEAR TO BE VERY LIKELY IN A SUPERCELL STORM MODE IF THEY DEVELOP IN THIS TRIPLE POINT BY 00Z AS CAPE IS FORECAST TO BE ON THE ORDER OF 3000 J/KG WITH DEEP LAYER SHEAR OF 50 KTS IN THE 0-6 KM AGL LAYER. THE SHAPE OF THE 0-3 KM HODOGRAPH IS EXPECTED TO BE CLOCKWISE LOOPING...AND DYNAMICALLY MORE FAVORABLE FOR RIGHT MOVING SUPERCELLS. AS A RESULT...EXPECT SUPERCELL STORM MOTION TO BE ALMOST DUE EAST LATE THIS AFTERNOON AND EARLY THIS EVENING. RIGHT MOVING SUPERCELLS LOOK MOST LIKELY SOUTH OF INTERSTATE 20 BASED ON THE FORECAST POSITION OF THE SURFACE LOW. THIS PLACES MUCH OF CENTRAL TEXAS IN THE PRIMARY THREAT CORRIDOR FOR DISCRETE SUPERCELLS. THE ENVIRONMENT IS SUPPORTIVE OF WELL-ORGANIZED SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL...DAMAGING WIND GUSTS AND TORNADOES. THE RESIDENTS OF CENTRAL TEXAS ARE ENCOURAGED TO PAY VERY CLOSE ATTENTION TO THE WEATHER THIS AFTERNOON AND EVENING AS A RESULT. OF COURSE IF THE SURFACE LOW IS FARTHER NORTH ...THE PRIMARY THREAT CORRIDOR FOR DISCRETE SUPERCELLS WILL MOVE NORTH WITH IT. AWAY FROM THIS PRIMARY THREAT CORRIDOR...IT IS CERTAINLY POSSIBLE FOR SUPERCELLS TO DEVELOP JUST ABOUT ANYWHERE IN THE WARM AIR ADVECTION REGIME INDICATED BY THE CLOCKWISE LOOPING LOW-LEVEL HODOGRAPH. THIS LIFT/FORCING IS NOT AS STRONG AND FOCUSED...SO IT IS SIMPLY MORE DIFFICULT TO KNOW IF...WHEN AND WHERE A SUPERCELL MAY DEVELOP IN THIS WARM AIR ADVECTION REGIME. AFTER 00Z...THE VERY STRONG FORCING FOR ASCENT ASSOCIATED WITH THE UPPER TROUGH OVER SOUTHERN ARIZONA AND NEW MEXICO IS EXPECTED TO LIFT OUT OVER THE SOUTHERN PLAINS. THE LATEST MODEL GUIDANCE IS CONVERGING ON A SOLUTION THAT SUGGESTS A VERY WELL ORGANIZED SQUALL LINE WILL DEVELOP NEAR CHILDRESS...AND MOVE SOUTHEAST TOWARDS NORTH TEXAS THIS EVENING. THERE ARE HINTS IN THE MODEL MASS FIELDS THAT THIS SQUALL LINE COULD POTENTIALLY BE VERY WELL ORGANIZED...AND MAY POSE A WIDESPREAD DAMAGING WIND THREAT AS IT MOVES SOUTHEAST ACROSS NORTH TEXAS OVERNIGHT. IF THIS SQUALL LINE DOES INDEED ORGANIZE...IT MAY PERSIST LONG ENOUGH AND PRODUCE ENOUGH STRAIGHT LINE WIND DAMAGE TO QUALIFY AS A DERECHO BY THE TIME IT EXITS THE CWA TO THE EAST WELL AFTER MIDNIGHT. THE PRIMARY TIME THIS SQUALL LINE/BOW-ECHO IS EXPECTED TO MOVE OVER NORTH TEXAS IS FROM 10 PM TO 3 AM. THE EXISTENCE OF THIS SQUALL LINE IS FAR FROM 100 PERCENT CERTAIN...BUT IT WILL PROBABLY ORGANIZE BASED ON THE CONSISTENT SIGNAL IN THIS MORNING`S HIGH RESOLUTION MODEL GUIDANCE. THE PRIMARY THREATS WITHIN THIS SQUALL LINE WOULD BE DAMAGING STRAIGHT LINE WINDS. ASSUMING THE SQUALL LINE MOVES THROUGH THE AREA AFTER SUNSET AS CURRENTLY FORECAST...THIS MAY REDUCE THE POTENTIAL FOR HIGH-END DAMAGING WINDS. REGARDLESS... WIND DAMAGE WOULD STILL BE LIKELY AS THIS SQUALL LIKE WOULD PROBABLY BE VERY WELL ORGANIZED. LARGE HAIL AND A BRIEF TORNADO MAY ALSO OCCUR IN THIS LINE...ASSUMING IT DEVELOPS. LAST BUT NOT LEAST...WE WILL ALSO BE MONITORING FOR HEAVY RAINFALL AND FLASH FLOODING POTENTIAL THIS AFTERNOON AND EVENING. IF A WARM FRONT SETS UP ALONG THE INTERSTATE 20 CORRIDOR...SCATTERED THUNDERSTORMS COULD DEVELOP ALONG THIS BOUNDARY AND TRAIN OVER AREAS TO THE NORTHEAST. THIS MAY EVOLVE INTO ANOTHER LOCALIZED FLASH FLOODING EVENT NORTH OF INTERSTATE 20 AND GENERALLY EAST OF INTERSTATE 35...VERY SIMILAR TO WHAT HAPPENED ON FRIDAY. WILL HOLD OFF ON A FLASH FLOOD WATCH FOR NOW AS CONFIDENCE IN THIS TAKING PLACE IS NOT HIGH AT THIS TIME. IF IT OCCURS...THESE LOCATIONS HAVE ALREADY RECEIVED QUITE A BIT OF RAINFALL ON FRIDAY...SO FLOODING WOULD TEND TO OCCUR QUICKLY IF STORMS BEGIN TO TRAIN OVER THIS REGION THROUGH TONIGHT. WILL CONTINUE TO MAKE SHORT TERM FORECAST UPDATES FOR CONVECTION MODE THROUGH THIS EVENING. EXPECT STORMS WILL START DEVELOPING NEAR THE SURFACE LOW AND EVOLVE INTO DISCRETE SUPERCELLS BY/AFTER 4 PM/21Z. CAVANAUGH && .AVIATION... /ISSUED 1256 PM CDT SUN APR 26 2015/ THE NEXT 24 HOURS WILL BE A VERY ACTIVE PERIOD FOR THE NORTH AND CENTRAL TEXAS TAF SITES WITH CONDITIONS FAVORABLE FOR NUMEROUS SHOWERS AND THUNDERSTORMS...SOME OF WHICH WILL BE SEVERE. CONVECTION IS ONGOING SOUTHWEST OF METROPLEX TAF SITES AND JUST TO THE WEST OF WACO. THIS ACTIVITY IS ELEVATED...AND BASED AROUND 10KFT. STEEP LAPSE RATES THROUGH THE COLUMN ARE LIKELY CONTRIBUTING TO TURBULENCE IN THIS AREA AS WELL. LIGHTNING WILL BE THE PRIMARY CONCERN AS THIS ACTIVITY CONTINUES TO PUSH TOWARDS THE METROPLEX THIS AFTERNOON. LATER THIS AFTERNOON AND EVENING...SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE DRYLINE AS SURFACE BASED INSTABILITY INCREASES DUE TO STRONG LOW-LEVEL MOISTURE ADVECTION. IT APPEARS THE GREATEST THREAT FOR SEVERE STORMS NEAR THE METROPLEX WILL OCCUR AFTER 02Z. HIGH RESOLUTION GUIDANCE IS KEYING IN ON AN AREA ALONG A STALLED FRONTAL BOUNDARY WHICH WOULD BE FAVORABLE FOR A STRONG LINEAR CONVECTIVE SYSTEM TO DEVELOP AND RIDE THE BOUNDARY EASTWARD TOWARD THE METROPLEX TAF SITES AROUND MIDNIGHT. THIS SOLUTION IS FAR FROM CERTAIN...BUT THERE IS DECENT AGREEMENT FROM SHORT TERM GUIDANCE WHICH LENDS CREDENCE TO THIS SCENARIO. THE MAIN THREAT WITH THIS SOLUTION WOULD BE VERY STRONG WINDS...BUT ALL TYPES OF SEVERE WEATHER WOULD STILL BE POSSIBLE IN THIS FAVORABLE ENVIRONMENT. THE LINE OF STORMS BEING ADVERTISED ALONG THE STATIONARY BOUNDARY WILL LIKELY BE TOO FAR NORTH TO IMPACT THE WACO TAF SITE. HOWEVER... WACO WILL BE THREATENED BY DISCRETE SUPERCELLS DEVELOPING LATE THIS AFTERNOON AND EARLY EVENING ALONG AND AHEAD OF THE DRYLINE. AGAIN...ALL TYPES OF SEVERE WEATHER WILL BE POSSIBLE LATE THIS AFTERNOON AND EVENING IN CENTRAL TEXAS. AFTER STORMS CLEAR OUT EARLY ON MONDAY MORNING...SOME BORDERLINE IFR/MVFR CIGS WILL BE POSSIBLE IN THE WAKE OF THE WIDESPREAD CONVECTION. HAVE KEPT TAF SITES ON THE LOW END OF MVFR FOR NOW SINCE THERE IS MUCH UNCERTAINTY ON THE POST-CONVECTIVE ENVIRONMENT TOMORROW. STALLEY && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 63 69 53 63 48 / 70 60 60 20 5 WACO, TX 64 76 54 65 46 / 60 60 40 10 0 PARIS, TX 56 66 52 63 45 / 70 70 70 30 5 DENTON, TX 62 66 52 63 45 / 70 60 60 20 5 MCKINNEY, TX 60 66 52 63 46 / 70 70 70 20 5 DALLAS, TX 63 69 53 63 50 / 70 60 60 20 5 TERRELL, TX 61 70 54 63 48 / 60 70 70 20 5 CORSICANA, TX 64 73 54 64 48 / 60 60 60 20 0 TEMPLE, TX 64 81 55 66 48 / 60 30 40 10 0 MINERAL WELLS, TX 61 71 53 63 46 / 70 60 40 10 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
143 PM CDT SUN APR 26 2015 .UPDATE... PLEASE SEE THE 18Z AVIATION DISCUSSION BELOW. && .AVIATION... VFR CONDITIONS ARE EXPECTED AT AREA TAF SITES THROUGH THE REMAINDER OF THIS AFTERNOON INTO THE EARLY EVENING HOURS. SOME AFTERNOON AND EARLY EVENING CONVECTION IS EXPECTED OVER THE RIO GRANDE PLAINS AND SOUTHERN EDWARDS PLATEAU TODAY. IT APPEARS THIS CONVECTION WILL REMAIN ISOLATED AND NOT IMPACT OUR TAF SITES. FOR THE EVENING AND OVERNIGHT HOURS...LOW CLOUDS RETURN TO THE I-35 CORRIDOR...RESULTING IN LOW END MVFR TO IFR CIGS. THE CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE DURING THE LATE EVENING AND OVERNIGHT HOURS ALONG THE I-35 CORRIDOR. WE WILL MENTION TEMPO GROUPS FOR TSRA FOR THE I-35 TAF SITES BETWEEN 08Z-12Z. CONVECTION SHOULD MOVE EAST OF ALL TAF SITES AFTER 13Z...LEAVING A BRIEF PERIOD OF MVFR CIGS UNTIL 15Z. MUCH DRIER AIR WILL RESULT IN VFR CONDITIONS FOR THE REMAINDER OF THE TAF FORECAST PERIOD. && .PREV DISCUSSION... /ISSUED 1003 AM CDT SUN APR 26 2015/ UPDATE...CORRECTED... MONITORING WHAT COULD BE A VERY ACTIVE AFTERNOON FOR SOUTH CENTRAL TEXAS. THROUGH MID MORNING...SHOWERS AND STORMS HAVE ALONG THE EASTERN HALF OF THE CWA IN A VERY MOIST BOUNDARY LAYER ENVIRONMENT. EML CAPPING/MID LEVEL DRY AIR IS LIMITING THE INTENSITY OF THIS DEVELOPMENT CURRENTLY BUT IT MAY BE A FOREWARNING OF THINGS TO COME THIS AFTERNOON AS THE CAP IS FORECAST TO ERODE BY EARLY AFTERNOON. ALSO BY EARLY AFTERNOON...THE DRYLINE CURRENTLY LOCATED JUST EAST OF THE BIG BEND AREA THROUGH MIDLAND WILL PROGRESS EASTWARD INTO THE EASTERN PORTIONS OF THE CWA AS FAVORABLE BOUNDARY LAYER FLOW ORIENTATION COULD RESULT IN A VERTICALLY VEERED PROFILE AND CONVERGENCE ALONG THE DRYLINE. AS THE MORNING CLOUD COVER MIXES OUT AND CAPPING DETERIORATES BY EARLY AFTERNOON...AN AREA EAST OF DEL RIO TO SONORA WILL BE A FOCUS FOR ISOLATED...BUT POTENTIALLY RAPIDLY DEVELOPING CONVECTION WITH THE PROSPECT OF LARGE HAIL...DAMAGING WINDS...AND POTENTIALLY SOME TORNADIC DEVELOPMENT THROUGH THE AFTERNOON. WHILE LATEST SHORT TERM MODELS SUGGEST CONVECTION SHOULD STAY NORTH OF THE I-10 CORRIDOR...DO THINK THE DECENT SHOT AT SEVERE POTENTIAL COULD EXTEND SOUTH TO THE HWY 57 CORRIDOR THIS AFTERNOON. SINCE HI RES MODELS SUCH AS TTU WRF AND HRRR ARE KEEPING CI WELL NORTH OF THE CWA THIS AFTERNOON...DID NOT INCREASE POPS ABOVE CHC WORDING THROUGH 00Z. BUT AS SPC HAS INCLUDED THE SAME GENERAL LOCATIONS PREVIOUSLY MENTIONED IN THE ENHANCED RISK...WOULD NOT BE SURPRISED TO SEE SOME ACTIVITY FURTHER SOUTH INTO OUR CWA THIS AFTERNOON. AS FOR OVERNIGHT STORM POTENTIAL...PREVIOUS FORECAST SEEMS TO BE ON TRACK WITH LATEST SHORT TERM MODEL RUNS. CONFIDENCE IS INCREASING FOR A LATE EVENING AND OVERNIGHT LINE OF POTENTIALLY SEVERE STORMS...MORE AS A STRAIGHT LINE WIND THREAT WITH LARGE HAIL AS WELL. TB && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 65 85 59 72 51 / 70 30 20 10 - AUSTIN BERGSTROM INTL AIRPORT 65 83 58 72 49 / 70 30 20 10 - NEW BRAUNFELS MUNI AIRPORT 66 84 59 73 50 / 60 30 10 10 - BURNET MUNI AIRPORT 62 83 56 70 49 / 70 30 30 20 - DEL RIO INTL AIRPORT 62 87 60 76 51 / 10 0 - - - GEORGETOWN MUNI AIRPORT 63 83 57 70 49 / 70 30 30 10 - HONDO MUNI AIRPORT 63 85 59 74 49 / 40 20 - - - SAN MARCOS MUNI AIRPORT 65 83 60 72 50 / 70 30 10 10 - LA GRANGE - FAYETTE REGIONAL 69 82 61 72 50 / 60 50 20 10 - SAN ANTONIO INTL AIRPORT 66 85 60 73 51 / 50 20 10 10 - STINSON MUNI AIRPORT 67 84 62 74 51 / 40 30 10 10 - && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...24 SYNOPTIC/GRIDS...03 PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1256 PM CDT SUN APR 26 2015 .AVIATION... THE NEXT 24 HOURS WILL BE A VERY ACTIVE PERIOD FOR THE NORTH AND CENTRAL TEXAS TAF SITES WITH CONDITIONS FAVORABLE FOR NUMEROUS SHOWERS AND THUNDERSTORMS...SOME OF WHICH WILL BE SEVERE. CONVECTION IS ONGOING SOUTHWEST OF METROPLEX TAF SITES AND JUST TO THE WEST OF WACO. THIS ACTIVITY IS ELEVATED...AND BASED AROUND 10KFT. STEEP LAPSE RATES THROUGH THE COLUMN ARE LIKELY CONTRIBUTING TO TURBULENCE IN THIS AREA AS WELL. LIGHTNING WILL BE THE PRIMARY CONCERN AS THIS ACTIVITY CONTINUES TO PUSH TOWARDS THE METROPLEX THIS AFTERNOON. LATER THIS AFTERNOON AND EVENING...SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE DRYLINE AS SURFACE BASED INSTABILITY INCREASES DUE TO STRONG LOW-LEVEL MOISTURE ADVECTION. IT APPEARS THE GREATEST THREAT FOR SEVERE STORMS NEAR THE METROPLEX WILL OCCUR AFTER 02Z. HIGH RESOLUTION GUIDANCE IS KEYING IN ON AN AREA ALONG A STALLED FRONTAL BOUNDARY WHICH WOULD BE FAVORABLE FOR A STRONG LINEAR CONVECTIVE SYSTEM TO DEVELOP AND RIDE THE BOUNDARY EASTWARD TOWARD THE METROPLEX TAF SITES AROUND MIDNIGHT. THIS SOLUTION IS FAR FROM CERTAIN...BUT THERE IS DECENT AGREEMENT FROM SHORT TERM GUIDANCE WHICH LENDS CREDENCE TO THIS SCENARIO. THE MAIN THREAT WITH THIS SOLUTION WOULD BE VERY STRONG WINDS...BUT ALL TYPES OF SEVERE WEATHER WOULD STILL BE POSSIBLE IN THIS FAVORABLE ENVIRONMENT. THE LINE OF STORMS BEING ADVERTISED ALONG THE STATIONARY BOUNDARY WILL LIKELY BE TOO FAR NORTH TO IMPACT THE WACO TAF SITE. HOWEVER... WACO WILL BE THREATENED BY DISCRETE SUPERCELLS DEVELOPING LATE THIS AFTERNOON AND EARLY EVENING ALONG AND AHEAD OF THE DRYLINE. AGAIN...ALL TYPES OF SEVERE WEATHER WILL BE POSSIBLE LATE THIS AFTERNOON AND EVENING IN CENTRAL TEXAS. AFTER STORMS CLEAR OUT EARLY ON MONDAY MORNING...SOME BORDERLINE IFR/MVFR CIGS WILL BE POSSIBLE IN THE WAKE OF THE WIDESPREAD CONVECTION. HAVE KEPT TAF SITES ON THE LOW END OF MVFR FOR NOW SINCE THERE IS MUCH UNCERTAINTY ON THE POST-CONVECTIVE ENVIRONMENT TOMORROW. STALLEY && .UPDATE... ...MESOSCALE FORECAST UPDATE REGARDING THE FORECAST FOR SEVERE STORMS ACROSS NORTH AND CENTRAL TEXAS TODAY... 12Z UPPER AIR ANALYSIS SHOWED AN INTENSE UPPER LEVEL TROUGH LOCATED OVER THE SOUTHERN ARIZONA AND NEW MEXICO BORDER. 500 MB HEIGHT FALLS OF 6 TO 12 DM WERE OBSERVED DOWNSTREAM OF THIS UPPER TROUGH...AND THE MAGNITUDE OF THESE HEIGHT FALLS IS INDICATIVE OF STRONG LARGE SCALE FORCING FOR ASCENT TO THE EAST. AT THE 700 MB LEVEL...A PLUME OF STEEP MID-LEVEL LAPSE RATES WAS OBSERVED...WITH A TEMPERATURE DIFFERENCE IN THE 700 TO 500 MB LAYER OF 22 DEG C LOCATED SOUTHWEST OF NORTH AND CENTRAL TEXAS. TO THE SOUTHWEST OF THIS PLUME OF ENHANCED LAPSE RATES...A 50 KT MID-LEVEL JET CORE WAS OBSERVED OVER NORTHERN MEXICO. CLOSER TO THE SURFACE...AT THE 850 MB LEVEL...DEEP MOISTURE WAS ONLY OBSERVED OVER SOUTHWEST TEXAS WITH A DRYLINE SUBJECTIVELY ANALYZED NEAR THE TX/OK BORDER...EXTENDING SOUTHWEST OVER WEST CENTRAL TEXAS AND INTO NORTHERN MEXICO ABOUT 60 MILES WEST OF DEL RIO. A 15Z SURFACE ANALYSIS OBSERVED RICH MOISTURE IN PLACE ALONG THE TX GULF COAST WITH MID 70S DEW POINTS OBSERVED WEST AND SOUTHWEST OF HOUSTON. FOR TODAY...NEARLY ALL SHORT RANGE MODEL GUIDANCE INDICATES THAT A SURFACE LOW PRESSURE SYSTEM WILL INTENSIFY RAPIDLY THIS AFTERNOON OVER WEST CENTRAL TEXAS. MOST GUIDANCE SHOWS SURFACE PRESSURE FALLING AT A RATE OF 2-3 MB PER HOUR LEADING UP TO 00Z. AT 15Z...THE LOWEST SURFACE PRESSURE OVER THE SOUTHERN HIGH PLAINS WAS AROUND 1002 MB...MOST GUIDANCE INDICATES THE SURFACE LOW`S PRESSURE WILL FALL TO 993 TO 995 MB BY 00Z. THAT MAGNITUDE OF PRESSURE FALL ASSOCIATED WITH THE SURFACE LOW IS FAIRLY INTENSE...AND SHOULD RESULT IN A CONVERGENCE OF PARAMETERS THAT WILL SUPPORT A LOCALIZED SEVERE WEATHER OUTBREAK ACROSS THE REGION THIS AFTERNOON AND EVENING. ONE OF THE KEY FORECAST CHALLENGES TODAY WILL BE DETERMINING WHERE THE SURFACE LOW MOVES AS THE RELATIVE THREATS FOR SUPERCELLS AND TORNADOES WILL VARY DEPENDING ON THE EXACT POSITION OF THIS LOW LATER THIS AFTERNOON. THE 12Z NAM AND 16Z HRRR INDICATE THE SURFACE LOW WILL BE LOCATED JUST SOUTH OF INTERSTATE 20 AND JUST NORTH OF SAN ANGELO. IF THIS POSITION FOR THE SURFACE LOW IS CORRECT...THE THREAT FOR DISCRETE SUPERCELLS WOULD BE MAXIMIZED TO THE EAST OF THE SURFACE LOW...WHERE A TRIPLE POINT WOULD LIKELY SET UP. SUPERCELLS WOULD BE MOST LIKELY TO DEVELOP NEAR THIS TRIPLE POINT...AND THEN MOVE EAST IN THE RELATIVELY STRONG SOUTHWESTERLY FLOW ALOFT. STORMS APPEAR TO BE VERY LIKELY IN A SUPERCELL STORM MODE IF THEY DEVELOP IN THIS TRIPLE POINT BY 00Z AS CAPE IS FORECAST TO BE ON THE ORDER OF 3000 J/KG WITH DEEP LAYER SHEAR OF 50 KTS IN THE 0-6 KM AGL LAYER. THE SHAPE OF THE 0-3 KM HODOGRAPH IS EXPECTED TO BE CLOCKWISE LOOPING...AND DYNAMICALLY MORE FAVORABLE FOR RIGHT MOVING SUPERCELLS. AS A RESULT...EXPECT SUPERCELL STORM MOTION TO BE ALMOST DUE EAST LATE THIS AFTERNOON AND EARLY THIS EVENING. RIGHT MOVING SUPERCELLS LOOK MOST LIKELY SOUTH OF INTERSTATE 20 BASED ON THE FORECAST POSITION OF THE SURFACE LOW. THIS PLACES MUCH OF CENTRAL TEXAS IN THE PRIMARY THREAT CORRIDOR FOR DISCRETE SUPERCELLS. THE ENVIRONMENT IS SUPPORTIVE OF WELL-ORGANIZED SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL...DAMAGING WIND GUSTS AND TORNADOES. THE RESIDENTS OF CENTRAL TEXAS ARE ENCOURAGED TO PAY VERY CLOSE ATTENTION TO THE WEATHER THIS AFTERNOON AND EVENING AS A RESULT. OF COURSE IF THE SURFACE LOW IS FARTHER NORTH ...THE PRIMARY THREAT CORRIDOR FOR DISCRETE SUPERCELLS WILL MOVE NORTH WITH IT. AWAY FROM THIS PRIMARY THREAT CORRIDOR...IT IS CERTAINLY POSSIBLE FOR SUPERCELLS TO DEVELOP JUST ABOUT ANYWHERE IN THE WARM AIR ADVECTION REGIME INDICATED BY THE CLOCKWISE LOOPING LOW-LEVEL HODOGRAPH. THIS LIFT/FORCING IS NOT AS STRONG AND FOCUSED...SO IT IS SIMPLY MORE DIFFICULT TO KNOW IF...WHEN AND WHERE A SUPERCELL MAY DEVELOP IN THIS WARM AIR ADVECTION REGIME. AFTER 00Z...THE VERY STRONG FORCING FOR ASCENT ASSOCIATED WITH THE UPPER TROUGH OVER SOUTHERN ARIZONA AND NEW MEXICO IS EXPECTED TO LIFT OUT OVER THE SOUTHERN PLAINS. THE LATEST MODEL GUIDANCE IS CONVERGING ON A SOLUTION THAT SUGGESTS A VERY WELL ORGANIZED SQUALL LINE WILL DEVELOP NEAR CHILDRESS...AND MOVE SOUTHEAST TOWARDS NORTH TEXAS THIS EVENING. THERE ARE HINTS IN THE MODEL MASS FIELDS THAT THIS SQUALL LINE COULD POTENTIALLY BE VERY WELL ORGANIZED...AND MAY POSE A WIDESPREAD DAMAGING WIND THREAT AS IT MOVES SOUTHEAST ACROSS NORTH TEXAS OVERNIGHT. IF THIS SQUALL LINE DOES INDEED ORGANIZE...IT MAY PERSIST LONG ENOUGH AND PRODUCE ENOUGH STRAIGHT LINE WIND DAMAGE TO QUALIFY AS A DERECHO BY THE TIME IT EXITS THE CWA TO THE EAST WELL AFTER MIDNIGHT. THE PRIMARY TIME THIS SQUALL LINE/BOW-ECHO IS EXPECTED TO MOVE OVER NORTH TEXAS IS FROM 10 PM TO 3 AM. THE EXISTENCE OF THIS SQUALL LINE IS FAR FROM 100 PERCENT CERTAIN...BUT IT WILL PROBABLY ORGANIZE BASED ON THE CONSISTENT SIGNAL IN THIS MORNING`S HIGH RESOLUTION MODEL GUIDANCE. THE PRIMARY THREATS WITHIN THIS SQUALL LINE WOULD BE DAMAGING STRAIGHT LINE WINDS. ASSUMING THE SQUALL LINE MOVES THROUGH THE AREA AFTER SUNSET AS CURRENTLY FORECAST...THIS MAY REDUCE THE POTENTIAL FOR HIGH-END DAMAGING WINDS. REGARDLESS... WIND DAMAGE WOULD STILL BE LIKELY AS THIS SQUALL LIKE WOULD PROBABLY BE VERY WELL ORGANIZED. LARGE HAIL AND A BRIEF TORNADO MAY ALSO OCCUR IN THIS LINE...ASSUMING IT DEVELOPS. LAST BUT NOT LEAST...WE WILL ALSO BE MONITORING FOR HEAVY RAINFALL AND FLASH FLOODING POTENTIAL THIS AFTERNOON AND EVENING. IF A WARM FRONT SETS UP ALONG THE INTERSTATE 20 CORRIDOR...SCATTERED THUNDERSTORMS COULD DEVELOP ALONG THIS BOUNDARY AND TRAIN OVER AREAS TO THE NORTHEAST. THIS MAY EVOLVE INTO ANOTHER LOCALIZED FLASH FLOODING EVENT NORTH OF INTERSTATE 20 AND GENERALLY EAST OF INTERSTATE 35...VERY SIMILAR TO WHAT HAPPENED ON FRIDAY. WILL HOLD OFF ON A FLASH FLOOD WATCH FOR NOW AS CONFIDENCE IN THIS TAKING PLACE IS NOT HIGH AT THIS TIME. IF IT OCCURS...THESE LOCATIONS HAVE ALREADY RECEIVED QUITE A BIT OF RAINFALL ON FRIDAY...SO FLOODING WOULD TEND TO OCCUR QUICKLY IF STORMS BEGIN TO TRAIN OVER THIS REGION THROUGH TONIGHT. WILL CONTINUE TO MAKE SHORT TERM FORECAST UPDATES FOR CONVECTION MODE THROUGH THIS EVENING. EXPECT STORMS WILL START DEVELOPING NEAR THE SURFACE LOW AND EVOLVE INTO DISCRETE SUPERCELLS BY/AFTER 4 PM/21Z. CAVANAUGH && .SYNOPSIS... THE FIRST PORTION OF TODAY WILL BE QUITE SIMILAR TO SATURDAY...WITH VERY WARM AND PLEASANT CONDITIONS. ONE DIFFERENCE WILL BE THE INCREASE IN LOW LEVEL MOISTURE IN RESPONSE TO THE APPROACH OF AN UPPER LEVEL LOW. THIS WILL SET THE STAGE FOR ACTIVE WEATHER THIS AFTERNOON THROUGH MONDAY...THEREAFTER...A MORE TRANQUIL PATTERN IS IN STORE FOR NORTH/CENTRAL TEXAS. && .SHORT TERM... THE MAIN CHALLENGE FOR THE SHORT TERM FORECAST WILL BE THE POTENTIAL FOR MULTIPLE ROUNDS OF CONVECTION /SOME STRONG TO SEVERE/ ACROSS THE WESTERN TWO THIRDS OF NORTH/CENTRAL TEXAS. WATER VAPOR IMAGERY AT THIS HOUR REVEALED THAT THE MAIN UPPER LOW THAT WILL BE RESPONSIBLE FOR TODAY/S SEVERE WEATHER CHANCES WAS LOCATED ACROSS SOUTHERN ARIZONA. THIS VERY DYNAMIC TROUGH WILL CONTINUE TO MOVE EASTWARD BEFORE CLOSING OFF LATER TODAY. LOW LEVEL MOISTURE WILL CONTINUE TO STREAM NORTHWARD INTO THE AREA BENEATH A STOUT EML THAT IS SIMULTANEOUSLY ADVECTING EASTWARD OFF OF THE HIGHER TERRAIN. THE STEEP LAPSE RATES ASSOCIATED WITH THE EML IN CONJUNCTION WITH THE ASCENT PRODUCED BY THE APPROACHING UPPER LOW /AS EVIDENCED BY 30 TO 40 METER HEIGHT FALLS/ SHOULD SUPPORT THE DEVELOPMENT OF ELEVATED CONVECTION MID TO LATE MORNING MAINLY ALONG AND WEST OF A BOWIE TO GLEN ROSE TO KILLEEN LINE. THE STEEP LAPSE RATES COMBINED WITH SUFFICIENT EFFECTIVE LAYER SHEAR MAY SUPPORT A MARGINALLY SEVERE HAIL THREAT IN THE MORNING...SHOULD STORMS DEVELOP. DURING THE AFTERNOON HOURS...ADDITIONAL CONVECTION IS EXPECTED TO DEVELOP AS A 100 KT UPPER LEVEL JET NOSES INTO THE SOUTHERN TX PANHANDLE AND A VORTICITY LOBE ROTATES AROUND THE BASE OF THE MAIN TROUGH OUT INTO WESTERN NORTH TEXAS. DURING THIS TIME...THE DRYLINE WILL CONTINUE TO SHARPEN NEAR THE BIG COUNTRY. THE STRONG LIFT...DIURNAL HEATING...AND INCREASING MOISTURE SHOULD ERODE SURFACE BASED CONVECTIVE INHIBITION. VERY HIGH CAPE VALUES ON THE ORDER OF 2500-3000 J/KG....MID LEVEL LAPSE RATES APPROACHING 8 C/KM AND 0-6 KM BULK SHEAR VALUES ON THE ORDER OF 45 TO 50 KNOTS WILL EASILY SUPPORT A LARGE AND DAMAGING HAIL THREAT. AS THE STORMS MOVE EAST AND NORTHEAST...GENERALLY BEYOND A BOWIE TO MINERAL WELLS TO WACO LINE THIS AFTERNOON...THE LOW LEVEL AIRMASS WILL BECOME INCREASINGLY DRIER WHICH INCREASES THE POTENTIAL FOR DESTRUCTIVE STRAIGHT LINE WINDS. WHILE TORNADOES WILL BE POSSIBLE WITH STORMS NEAR AND JUST EAST OF THE DRYLINE THIS AFTERNOON...THIS THREAT ACTUALLY INCREASES DURING THE EARLY EVENING HOURS AS LOW LEVEL WINDS INCREASE AND BACK IN RESPONSE TO THE UPPER LOW MOVING INTO WEST TEXAS. THIS SHOULD RESULT IN LARGE HODOGRAPHS WHILE CINH IS STILL LOW. AN ENHANCED TORNADO RISK MAY DEVELOP ACROSS OUR SOUTHWESTERN ZONES THAT WOULD INCLUDE THE WACO/TEMPLE/KILLEEN AREAS. UNLIKE MOST SEVERE EVENTS...WE EXPECT CONVECTION TO CONTINUE TO FIRE THROUGH THE OVERNIGHT HOURS AS THE UPPER LEVEL LOW REMAINS SITUATED ACROSS THE REGION. THIS WILL ALSO FOSTER AN INCREASING HEAVY RAIN THREAT AS CONTINUED ADVECTION OF WARM MOIST AIR INTO THE REGION IS EXPECTED. THE BOTTOM LINE IS THAT ALL INTERESTS ACROSS NORTH AND CENTRAL TEXAS NEED TO PAY PARTICULARLY CLOSE ATTENTION TO WEATHER CONDITIONS TODAY AS THE POTENTIAL EXISTS FOR HIGH IMPACT SIGNIFICANT SEVERE WEATHER IN THE FORM OF LARGE HAIL...DESTRUCTIVE WINDS...AND A FEW TORNADOES. && .LONG TERM... ADDITIONAL CHANCES FOR PRECIPITATION WILL REMAIN ON MONDAY AS THE CLOSED LOW MEANDERS ACROSS THE REGION. A FRONTAL BOUNDARY WILL STALL OUT NEAR THE RED RIVER AND MAY EVEN DRIFT SOUTHWARD. STRONG LOW LEVEL THETA-E ADVECTION WILL CONTINUE TO TRANSPORT WARM MOIST AIR NORTHWARD INTO PORTIONS OF NORTH/CENTRAL TEXAS. WITH THE LACK OF A STRONG CAP...EXPECT WIDESPREAD TO NUMEROUS SHOWER AND THUNDERSTORM ACTIVITY. THE WIDESPREAD NATURE OF SHOWERS AND STORMS MAY MITIGATE THE LARGER SEVERE WEATHER POTENTIAL ON MONDAY...EXCEPT ACROSS FAR SOUTHERN ZONES WHERE SOME HEATING WILL BE POSSIBLE. PERHAPS THE LARGER THREAT WILL BE THE POTENTIAL FOR HEAVY RAIN ON MONDAY AS PWAT VALUES ARE EXPECTED TO CLIMB TOWARDS THE 1.15-1.25 INCH RANGE. FOR NOW WILL HOLD OFF ON ANY FLOOD WATCHES PARTICULARLY FOR THE NORTHERN ZONES UNTIL WE GET CLOSER TO THE EVENT. RAIN CHANCES SHOULD TAPER OFF BY TUESDAY MORNING AS THE COLD FRONT PUSHES TOWARDS THE SOUTH AND THE UPPER FORCING DEPARTS THE REGION. COOLER CONDITIONS CAN BE EXPECTED ON TUESDAY AND WEDNESDAY WITH LITTLE TO NO CHANCES OF PRECIPITATION AS THE OMEGA PATTERN ESTABLISHES ITSELF. THE NEXT CHANCE FOR RAIN MAY BE TOWARDS THE BEGINNING OF MAY. 15-BAIN/TR.92 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 84 61 71 54 64 / 40 70 70 60 20 WACO, TX 85 65 76 54 67 / 50 60 50 40 10 PARIS, TX 83 57 67 53 62 / 30 70 70 70 30 DENTON, TX 83 60 67 52 64 / 40 70 70 60 20 MCKINNEY, TX 83 59 68 53 64 / 40 70 70 70 20 DALLAS, TX 85 61 70 54 64 / 40 70 70 60 20 TERRELL, TX 85 61 71 55 64 / 40 60 70 70 20 CORSICANA, TX 85 65 73 54 65 / 30 60 60 60 20 TEMPLE, TX 86 65 80 54 67 / 50 60 40 40 10 MINERAL WELLS, TX 82 62 74 55 65 / 50 70 60 40 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 77
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1239 PM CDT SUN APR 26 2015 .UPDATE... ...MESOSCALE FORECAST UPDATE REGARDING THE FORECAST FOR SEVERE STORMS ACROSS NORTH AND CENTRAL TEXAS TODAY... 12Z UPPER AIR ANALYSIS SHOWED AN INTENSE UPPER LEVEL TROUGH LOCATED OVER THE SOUTHERN ARIZONA AND NEW MEXICO BORDER. 500 MB HEIGHT FALLS OF 6 TO 12 DM WERE OBSERVED DOWNSTREAM OF THIS UPPER TROUGH...AND THE MAGNITUDE OF THESE HEIGHT FALLS IS INDICATIVE OF STRONG LARGE SCALE FORCING FOR ASCENT TO THE EAST. AT THE 700 MB LEVEL...A PLUME OF STEEP MID-LEVEL LAPSE RATES WAS OBSERVED...WITH A TEMPERATURE DIFFERENCE IN THE 700 TO 500 MB LAYER OF 22 DEG C LOCATED SOUTHWEST OF NORTH AND CENTRAL TEXAS. TO THE SOUTHWEST OF THIS PLUME OF ENHANCED LAPSE RATES...A 50 KT MID-LEVEL JET CORE WAS OBSERVED OVER NORTHERN MEXICO. CLOSER TO THE SURFACE...AT THE 850 MB LEVEL...DEEP MOISTURE WAS ONLY OBSERVED OVER SOUTHWEST TEXAS WITH A DRYLINE SUBJECTIVELY ANALYZED NEAR THE TX/OK BORDER...EXTENDING SOUTHWEST OVER WEST CENTRAL TEXAS AND INTO NORTHERN MEXICO ABOUT 60 MILES WEST OF DEL RIO. A 15Z SURFACE ANALYSIS OBSERVED RICH MOISTURE IN PLACE ALONG THE TX GULF COAST WITH MID 70S DEW POINTS OBSERVED WEST AND SOUTHWEST OF HOUSTON. FOR TODAY...NEARLY ALL SHORT RANGE MODEL GUIDANCE INDICATES THAT A SURFACE LOW PRESSURE SYSTEM WILL INTENSIFY RAPIDLY THIS AFTERNOON OVER WEST CENTRAL TEXAS. MOST GUIDANCE SHOWS SURFACE PRESSURE FALLING AT A RATE OF 2-3 MB PER HOUR LEADING UP TO 00Z. AT 15Z...THE LOWEST SURFACE PRESSURE OVER THE SOUTHERN HIGH PLAINS WAS AROUND 1002 MB...MOST GUIDANCE INDICATES THE SURFACE LOW`S PRESSURE WILL FALL TO 993 TO 995 MB BY 00Z. THAT MAGNITUDE OF PRESSURE FALL ASSOCIATED WITH THE SURFACE LOW IS FAIRLY INTENSE...AND SHOULD RESULT IN A CONVERGENCE OF PARAMETERS THAT WILL SUPPORT A LOCALIZED SEVERE WEATHER OUTBREAK ACROSS THE REGION THIS AFTERNOON AND EVENING. ONE OF THE KEY FORECAST CHALLENGES TODAY WILL BE DETERMINING WHERE THE SURFACE LOW MOVES AS THE RELATIVE THREATS FOR SUPERCELLS AND TORNADOES WILL VARY DEPENDING ON THE EXACT POSITION OF THIS LOW LATER THIS AFTERNOON. THE 12Z NAM AND 16Z HRRR INDICATE THE SURFACE LOW WILL BE LOCATED JUST SOUTH OF INTERSTATE 20 AND JUST NORTH OF SAN ANGELO. IF THIS POSITION FOR THE SURFACE LOW IS CORRECT...THE THREAT FOR DISCRETE SUPERCELLS WOULD BE MAXIMIZED TO THE EAST OF THE SURFACE LOW...WHERE A TRIPLE POINT WOULD LIKELY SET UP. SUPERCELLS WOULD BE MOST LIKELY TO DEVELOP NEAR THIS TRIPLE POINT...AND THEN MOVE EAST IN THE RELATIVELY STRONG SOUTHWESTERLY FLOW ALOFT. STORMS APPEAR TO BE VERY LIKELY IN A SUPERCELL STORM MODE IF THEY DEVELOP IN THIS TRIPLE POINT BY 00Z AS CAPE IS FORECAST TO BE ON THE ORDER OF 3000 J/KG WITH DEEP LAYER SHEAR OF 50 KTS IN THE 0-6 KM AGL LAYER. THE SHAPE OF THE 0-3 KM HODOGRAPH IS EXPECTED TO BE CLOCKWISE LOOPING...AND DYNAMICALLY MORE FAVORABLE FOR RIGHT MOVING SUPERCELLS. AS A RESULT...EXPECT SUPERCELL STORM MOTION TO BE ALMOST DUE EAST LATE THIS AFTERNOON AND EARLY THIS EVENING. RIGHT MOVING SUPERCELLS LOOK MOST LIKELY SOUTH OF INTERSTATE 20 BASED ON THE FORECAST POSITION OF THE SURFACE LOW. THIS PLACES MUCH OF CENTRAL TEXAS IN THE PRIMARY THREAT CORRIDOR FOR DISCRETE SUPERCELLS. THE ENVIRONMENT IS SUPPORTIVE OF WELL-ORGANIZED SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL...DAMAGING WIND GUSTS AND TORNADOES. THE RESIDENTS OF CENTRAL TEXAS ARE ENCOURAGED TO PAY VERY CLOSE ATTENTION TO THE WEATHER THIS AFTERNOON AND EVENING AS A RESULT. OF COURSE IF THE SURFACE LOW IS FARTHER NORTH ...THE PRIMARY THREAT CORRIDOR FOR DISCRETE SUPERCELLS WILL MOVE NORTH WITH IT. AWAY FROM THIS PRIMARY THREAT CORRIDOR...IT IS CERTAINLY POSSIBLE FOR SUPERCELLS TO DEVELOP JUST ABOUT ANYWHERE IN THE WARM AIR ADVECTION REGIME INDICATED BY THE CLOCKWISE LOOPING LOW-LEVEL HODOGRAPH. THIS LIFT/FORCING IS NOT AS STRONG AND FOCUSED...SO IT IS SIMPLY MORE DIFFICULT TO KNOW IF...WHEN AND WHERE A SUPERCELL MAY DEVELOP IN THIS WARM AIR ADVECTION REGIME. AFTER 00Z...THE VERY STRONG FORCING FOR ASCENT ASSOCIATED WITH THE UPPER TROUGH OVER SOUTHERN ARIZONA AND NEW MEXICO IS EXPECTED TO LIFT OUT OVER THE SOUTHERN PLAINS. THE LATEST MODEL GUIDANCE IS CONVERGING ON A SOLUTION THAT SUGGESTS A VERY WELL ORGANIZED SQUALL LINE WILL DEVELOP NEAR CHILDRESS...AND MOVE SOUTHEAST TOWARDS NORTH TEXAS THIS EVENING. THERE ARE HINTS IN THE MODEL MASS FIELDS THAT THIS SQUALL LINE COULD POTENTIALLY BE VERY WELL ORGANIZED...AND MAY POSE A WIDESPREAD DAMAGING WIND THREAT AS IT MOVES SOUTHEAST ACROSS NORTH TEXAS OVERNIGHT. IF THIS SQUALL LINE DOES INDEED ORGANIZE...IT MAY PERSIST LONG ENOUGH AND PRODUCE ENOUGH STRAIGHT LINE WIND DAMAGE TO QUALIFY AS A DERECHO BY THE TIME IT EXITS THE CWA TO THE EAST WELL AFTER MIDNIGHT. THE PRIMARY TIME THIS SQUALL LINE/BOW-ECHO IS EXPECTED TO MOVE OVER NORTH TEXAS IS FROM 10 PM TO 3 AM. THE EXISTENCE OF THIS SQUALL LINE IS FAR FROM 100 PERCENT CERTAIN...BUT IT WILL PROBABLY ORGANIZE BASED ON THE CONSISTENT SIGNAL IN THIS MORNING`S HIGH RESOLUTION MODEL GUIDANCE. THE PRIMARY THREATS WITHIN THIS SQUALL LINE WOULD BE DAMAGING STRAIGHT LINE WINDS. ASSUMING THE SQUALL LINE MOVES THROUGH THE AREA AFTER SUNSET AS CURRENTLY FORECAST...THIS MAY REDUCE THE POTENTIAL FOR HIGH-END DAMAGING WINDS. REGARDLESS... WIND DAMAGE WOULD STILL BE LIKELY AS THIS SQUALL LIKE WOULD PROBABLY BE VERY WELL ORGANIZED. LARGE HAIL AND A BRIEF TORNADO MAY ALSO OCCUR IN THIS LINE...ASSUMING IT DEVELOPS. LAST BUT NOT LEAST...WE WILL ALSO BE MONITORING FOR HEAVY RAINFALL AND FLASH FLOODING POTENTIAL THIS AFTERNOON AND EVENING. IF A WARM FRONT SETS UP ALONG THE INTERSTATE 20 CORRIDOR...SCATTERED THUNDERSTORMS COULD DEVELOP ALONG THIS BOUNDARY AND TRAIN OVER AREAS TO THE NORTHEAST. THIS MAY EVOLVE INTO ANOTHER LOCALIZED FLASH FLOODING EVENT NORTH OF INTERSTATE 20 AND GENERALLY EAST OF INTERSTATE 35...VERY SIMILAR TO WHAT HAPPENED ON FRIDAY. WILL HOLD OFF ON A FLASH FLOOD WATCH FOR NOW AS CONFIDENCE IN THIS TAKING PLACE IS NOT HIGH AT THIS TIME. IF IT OCCURS...THESE LOCATIONS HAVE ALREADY RECEIVED QUITE A BIT OF RAINFALL ON FRIDAY...SO FLOODING WOULD TEND TO OCCUR QUICKLY IF STORMS BEGIN TO TRAIN OVER THIS REGION THROUGH TONIGHT. WILL CONTINUE TO MAKE SHORT TERM FORECAST UPDATES FOR CONVECTION MODE THROUGH THIS EVENING. EXPECT STORMS WILL START DEVELOPING NEAR THE SURFACE LOW AND EVOLVE INTO DISCRETE SUPERCELLS BY/AFTER 4 PM/21Z. CAVANAUGH && .AVIATION... /ISSUED 637 AM CDT SUN APR 26 2015/ FIRST CHALLENGE IS IFR STRATUS THAT IS MOVING NORTHWARD FROM CENTRAL AND SOUTHEAST TEXAS. THIS CLOUD DECK SHOULD AFFECT DAL AFTER 13Z...AND MAY CLIP GKY/DFW AS WELL. THIS MOISTURE LAYER IS THIN AND STRATUS SHOULD ERODE BY 15Z OR 16Z. VERY STEEP LAPSE RATES MOVE INTO THE AREA BY MIDDAY AND THERE IS ACTUALLY REALLY GOOD MODEL AGREEMENT IN BRINGING A PLUME OF MID LEVEL MOISTURE AND LIFT INTO THE AREA EARLY-MID AFTERNOON. THIS SHOULD BE SUFFICIENT FOR HIGH BASED OR ELEVATED THUNDERSTORMS AS THERE IS ABOUT 400-700 J/KG OF INSTABILITY FROM PARCELS LIFTED NEAR 12000FT. DRY AIR BELOW THIS ACTIVITY WILL EXIST AND WOULD ENHANCE TURBULENCE AND SURFACE WIND GUSTS...EVEN IF THERE IS LITTLE RAINFALL. WILL SHOW A 2 HOUR WINDOW OF VCTS FOR THIS WAVE OF ACTIVITY FROM 20-22Z...BUT TIMING IS NOT CERTAIN AT THIS POINT. THE SURFACE AIRMASS WILL CONTINUE TO DESTABILIZE DURING THE LATE AFTERNOON AND EVENING HOURS AS MOISTURE INCREASES. THIS WILL OPEN THE DOOR FOR SURFACE BASED CONVECTION MOVING IN FROM THE WEST AFTER IT FIRES ON THE DRY LINE. CONFIDENCE IS NOT ESPECIALLY HIGH THAT THIS ROUND OF ACTIVITY WILL IMPACT TAF SITES...BUT SINCE THERE IS THE POTENTIAL FOR SEVERE STORM WILL SHOW VCTS FROM 00Z TO 04Z. RAIN AND THUNDERSTORM CHANCES INCREASE IN THE LATE EVENING AND OVERNIGHT HOURS WHEN A MORE SOLID LINE OF STORMS SHOULD DEVELOP AND MOVE IN FROM THE WEST. THIS IS WHEN UPPER FORCING WILL BE STRONGEST. WILL SHOW TSRA FROM 4Z-9Z. AFTER THAT WILL LEAVE THUNDER OUT OF TAFS DUE TO LOW CONFIDENCE...BUT KEEP SHOWERS MENTIONED WITH MVFR CIGS PREVAILING BEHIND THE FRONT. TR.92 && .SYNOPSIS... THE FIRST PORTION OF TODAY WILL BE QUITE SIMILAR TO SATURDAY...WITH VERY WARM AND PLEASANT CONDITIONS. ONE DIFFERENCE WILL BE THE INCREASE IN LOW LEVEL MOISTURE IN RESPONSE TO THE APPROACH OF AN UPPER LEVEL LOW. THIS WILL SET THE STAGE FOR ACTIVE WEATHER THIS AFTERNOON THROUGH MONDAY...THEREAFTER...A MORE TRANQUIL PATTERN IS IN STORE FOR NORTH/CENTRAL TEXAS. && .SHORT TERM... THE MAIN CHALLENGE FOR THE SHORT TERM FORECAST WILL BE THE POTENTIAL FOR MULTIPLE ROUNDS OF CONVECTION /SOME STRONG TO SEVERE/ ACROSS THE WESTERN TWO THIRDS OF NORTH/CENTRAL TEXAS. WATER VAPOR IMAGERY AT THIS HOUR REVEALED THAT THE MAIN UPPER LOW THAT WILL BE RESPONSIBLE FOR TODAY/S SEVERE WEATHER CHANCES WAS LOCATED ACROSS SOUTHERN ARIZONA. THIS VERY DYNAMIC TROUGH WILL CONTINUE TO MOVE EASTWARD BEFORE CLOSING OFF LATER TODAY. LOW LEVEL MOISTURE WILL CONTINUE TO STREAM NORTHWARD INTO THE AREA BENEATH A STOUT EML THAT IS SIMULTANEOUSLY ADVECTING EASTWARD OFF OF THE HIGHER TERRAIN. THE STEEP LAPSE RATES ASSOCIATED WITH THE EML IN CONJUNCTION WITH THE ASCENT PRODUCED BY THE APPROACHING UPPER LOW /AS EVIDENCED BY 30 TO 40 METER HEIGHT FALLS/ SHOULD SUPPORT THE DEVELOPMENT OF ELEVATED CONVECTION MID TO LATE MORNING MAINLY ALONG AND WEST OF A BOWIE TO GLEN ROSE TO KILLEEN LINE. THE STEEP LAPSE RATES COMBINED WITH SUFFICIENT EFFECTIVE LAYER SHEAR MAY SUPPORT A MARGINALLY SEVERE HAIL THREAT IN THE MORNING...SHOULD STORMS DEVELOP. DURING THE AFTERNOON HOURS...ADDITIONAL CONVECTION IS EXPECTED TO DEVELOP AS A 100 KT UPPER LEVEL JET NOSES INTO THE SOUTHERN TX PANHANDLE AND A VORTICITY LOBE ROTATES AROUND THE BASE OF THE MAIN TROUGH OUT INTO WESTERN NORTH TEXAS. DURING THIS TIME...THE DRYLINE WILL CONTINUE TO SHARPEN NEAR THE BIG COUNTRY. THE STRONG LIFT...DIURNAL HEATING...AND INCREASING MOISTURE SHOULD ERODE SURFACE BASED CONVECTIVE INHIBITION. VERY HIGH CAPE VALUES ON THE ORDER OF 2500-3000 J/KG....MID LEVEL LAPSE RATES APPROACHING 8 C/KM AND 0-6 KM BULK SHEAR VALUES ON THE ORDER OF 45 TO 50 KNOTS WILL EASILY SUPPORT A LARGE AND DAMAGING HAIL THREAT. AS THE STORMS MOVE EAST AND NORTHEAST...GENERALLY BEYOND A BOWIE TO MINERAL WELLS TO WACO LINE THIS AFTERNOON...THE LOW LEVEL AIRMASS WILL BECOME INCREASINGLY DRIER WHICH INCREASES THE POTENTIAL FOR DESTRUCTIVE STRAIGHT LINE WINDS. WHILE TORNADOES WILL BE POSSIBLE WITH STORMS NEAR AND JUST EAST OF THE DRYLINE THIS AFTERNOON...THIS THREAT ACTUALLY INCREASES DURING THE EARLY EVENING HOURS AS LOW LEVEL WINDS INCREASE AND BACK IN RESPONSE TO THE UPPER LOW MOVING INTO WEST TEXAS. THIS SHOULD RESULT IN LARGE HODOGRAPHS WHILE CINH IS STILL LOW. AN ENHANCED TORNADO RISK MAY DEVELOP ACROSS OUR SOUTHWESTERN ZONES THAT WOULD INCLUDE THE WACO/TEMPLE/KILLEEN AREAS. UNLIKE MOST SEVERE EVENTS...WE EXPECT CONVECTION TO CONTINUE TO FIRE THROUGH THE OVERNIGHT HOURS AS THE UPPER LEVEL LOW REMAINS SITUATED ACROSS THE REGION. THIS WILL ALSO FOSTER AN INCREASING HEAVY RAIN THREAT AS CONTINUED ADVECTION OF WARM MOIST AIR INTO THE REGION IS EXPECTED. THE BOTTOM LINE IS THAT ALL INTERESTS ACROSS NORTH AND CENTRAL TEXAS NEED TO PAY PARTICULARLY CLOSE ATTENTION TO WEATHER CONDITIONS TODAY AS THE POTENTIAL EXISTS FOR HIGH IMPACT SIGNIFICANT SEVERE WEATHER IN THE FORM OF LARGE HAIL...DESTRUCTIVE WINDS...AND A FEW TORNADOES. && .LONG TERM... ADDITIONAL CHANCES FOR PRECIPITATION WILL REMAIN ON MONDAY AS THE CLOSED LOW MEANDERS ACROSS THE REGION. A FRONTAL BOUNDARY WILL STALL OUT NEAR THE RED RIVER AND MAY EVEN DRIFT SOUTHWARD. STRONG LOW LEVEL THETA-E ADVECTION WILL CONTINUE TO TRANSPORT WARM MOIST AIR NORTHWARD INTO PORTIONS OF NORTH/CENTRAL TEXAS. WITH THE LACK OF A STRONG CAP...EXPECT WIDESPREAD TO NUMEROUS SHOWER AND THUNDERSTORM ACTIVITY. THE WIDESPREAD NATURE OF SHOWERS AND STORMS MAY MITIGATE THE LARGER SEVERE WEATHER POTENTIAL ON MONDAY...EXCEPT ACROSS FAR SOUTHERN ZONES WHERE SOME HEATING WILL BE POSSIBLE. PERHAPS THE LARGER THREAT WILL BE THE POTENTIAL FOR HEAVY RAIN ON MONDAY AS PWAT VALUES ARE EXPECTED TO CLIMB TOWARDS THE 1.15-1.25 INCH RANGE. FOR NOW WILL HOLD OFF ON ANY FLOOD WATCHES PARTICULARLY FOR THE NORTHERN ZONES UNTIL WE GET CLOSER TO THE EVENT. RAIN CHANCES SHOULD TAPER OFF BY TUESDAY MORNING AS THE COLD FRONT PUSHES TOWARDS THE SOUTH AND THE UPPER FORCING DEPARTS THE REGION. COOLER CONDITIONS CAN BE EXPECTED ON TUESDAY AND WEDNESDAY WITH LITTLE TO NO CHANCES OF PRECIPITATION AS THE OMEGA PATTERN ESTABLISHES ITSELF. THE NEXT CHANCE FOR RAIN MAY BE TOWARDS THE BEGINNING OF MAY. 15-BAIN/TR.92 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 84 61 71 54 64 / 40 70 70 60 20 WACO, TX 85 65 76 54 67 / 50 60 50 40 10 PARIS, TX 83 57 67 53 62 / 30 70 70 70 30 DENTON, TX 83 60 67 52 64 / 40 70 70 60 20 MCKINNEY, TX 83 59 68 53 64 / 40 70 70 70 20 DALLAS, TX 85 61 70 54 64 / 40 70 70 60 20 TERRELL, TX 85 61 71 55 64 / 40 60 70 70 20 CORSICANA, TX 85 65 73 54 65 / 30 60 60 60 20 TEMPLE, TX 86 65 80 54 67 / 50 60 40 40 10 MINERAL WELLS, TX 82 62 74 55 65 / 50 70 60 40 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
410 PM MDT SUN APR 26 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 410 PM MDT SUN APR 26 2015 CONVECTION HAS OVERSPREAD MUCH OF CARBON COUNTY AND THE CHEYENNE RIDGE THIS AFTERNOON AS THE SHORTWAVE MOVES UP FROM COLORADO. THUNDERSTORMS ARE MOST PROLIFIC OUT OVER SOUTHERN CARBON COUNTY AND ARE QUITE THE LIGHTNING PRODUCERS. TEMPERATURES ARE HOLDING IN THE UPPER 30S TO LOW 40S IN THE LOWER ELEVATIONS IN THIS AREA...WITH LOW TO MID 30S IN THE MOUNTAINS AS STORMS MOVE OVERHEAD SO THINK THAT SNOW LEVELS MAY BE A BIT HIGHER THAN 8000 FEET OVERALL. THE STRENGTHENING INVERTED SFC TROUGH IS KEEPING THE COLD FRONT AT BAY WHILE ALOFT...WATER VAPOR IMAGERY DEPICTS A SORT OF ZONAL SHORTWAVE RIDGE OVERHEAD. IT WOULD APPEAR THAT BOTH FEATURES ARE KEEPING THE SIGNIFICANTLY COLDER TEMPS FROM INVADING THE FORECAST AREA FOR NOW. STILL EXPECT THE COLD FRONT TO DROP SOUTH LATE TONIGHT THROUGH MONDAY MORNING WHILE THE UPPER LEVEL DEFORMATION ZONE MOVES OVERHEAD...WHICH WILL BRING IN COLDER AIR AND MAINTAIN PRECIP CHANCES ACROSS THE FORECAST AREA THROUGH TONIGHT ESPECIALLYALONG THE LARAMIE RANGE AND WYO PLAINS. WILL SEE SNOW IN THE HIGHER ELEVATIONS ABOVE 7500 FEET THIS EVENING DROPPING TO 6500 FEET OVERNIGHT...AND SHOULD MIX DOWN EVEN LOWER AS THE COLD FRONT MOVES NORTH TO SOUTH OVERNIGHT. WILL LEAVE THE WINTER WEATHER ADVISORY FOR NOW AS THERE IS PLENTY OF TIME FOR CONVECTION AND DEFORMATION BAND TO ACCUMULATE SNOW IN THE SOUTHERN LARAMIE AND SNOWY RANGES THROUGH TONIGHT. WITH THE COMBINATION DEFORMATION BAND AND ALSO SOME MERIDIONAL JET ENERGY SNEAKING IN FROM THE WEST OVERNIGHT...COULD ALSO SEE UP TO 5 INCHES IN THE SIERRA MADRE AND NORTHERN LARAMIE RANGE MOUNTAINS TONIGHT...WITH AN INCH OR LESS OF ACCUMULATION POSSIBLE IN THE LOWER ELEVATIONS OF S/E WYO WITH THE COLD FRONT BY MONDAY MORNING. LIKELY TO SEE FOG OVERSPREAD THE PLAINS IN THIS PATTERN AGAIN AS WELL...SO WILL KEEP MENTION OF WIDESPREAD AREAS OF FOG IN THE FORECAST THROUGH MONDAY MORNING. FOR MONDAY...THE UPPER JET WILL WEAKEN AS IT SHIFTS NORTH WITH THE MIDLEVEL TROUGH MOVING OVERHEAD. WILL SEE SHOWERS CONTINUE ON AND OFF THROUGH THE DAY WITH THE FAVORED LOCATIONS ALONG NORTHEAST FACING SLOPES OF TERRAIN FEATURES. NOT LOOKING AT SIGNIFICANT CAA BEHIND THE COLD FRONT OVERNIGHT SO TEMPS SHOULD MODERATE WITH DAYTIME HEATING ENOUGH TO KEEP SNOW CONFINED TO THE MOUNTAINS. IT IS NOT OUT OF THE QUESTION TO SEE SNOW MIX WITH RAIN AT TIMES THOUGH EVEN ACROSS THE PLAINS AS 700MB TEMPS WILL BE AROUND MINUS 4C THROUGH THE DAY. CONDITIONS WILL DRY OUT MONDAY NIGHT THROUGH TUESDAY AS THE UPPER LEVEL RIDGE MOVES IN FROM THE WEST IN THE WAKE OF THE DEPARTING UPPER LOW. HIGHS SHOULD RETURN TO THE 50S/60S BY TUESDAY. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 PM MDT SUN APR 26 2015 UPPER RIDGE BUILDING INTO THE AREA TUESDAY NIGHT WITH DRIER CONDITIONS CONTINUING. LOOKS LIKE DRY WEATHER SHOULD STAY WITH US THROUGH THURSDAY BEFORE ANOTHER SHORTWAVE MOVES INTO THE AREA FROM THE NORTHWEST. PRETTY WARM TEMPERATURES EXPECTED AS 700MB TEMPERATURES CLIMB TO AROUND +6C THURSDAY AFTERNOON. NEXT CHANCE FOR PRECIP LOOKS TO BE THURSDAY NIGHT INTO FRIDAY AS AN UPPER SHORTWAVE AND ASSOCIATED COLD FRONT MOVES INTO THE AREA. BOTH THE GFS AND ECMWF BRING THE FRONT INTO THE AREA AROUND 06Z FRIDAY (THURSDAY NIGHT) WITH SHOWERS DEVELOPING OVER THE SNOWY AND SIERRA MADRE RANGES. FRONTAL BOUNDARY LOOKS TO STALL NEAR THE WYOMING/COLORADO BORDER FRIDAY AND PERSISTS INTO THE WEEKEND. BOTH THE GFS AND ECMWF PAINTING FAIRLY WIDESPREAD QPF ALONG THE NORTH SIDE OF THIS FRONT OVER SOUTHERN WYOMING SATURDAY INTO SUNDAY. FREEZING LINE WELL NORTH ACROSS NORTHERN WYOMING...SO DO THINK MOST OF THIS PRECIPITATION WILL FALL AS RAIN NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1149 AM MDT SUN APR 26 2015 IFR TO MVFR ACROSS SOUTHEAST WYOMING AND NEBRASKA PANHANDLE THROUGH THE TAF PERIOD. HRRR GUIDANCE USED FOR THE 18Z TAFS WHICH SHOWS AREAS EAST OF THE LARAMIE RANGE STAYING IFR THROUGH THE LATE AFTERNOON. COULD SEE A LIFT TO MVFR OUT IN THE PANHANDLE FOR KAIA AND KCDR AS THE AFTERNOON PROGRESSES. SHOULD SEE A FAIRLY RAPID DETERIORATION AFTER SUNSET WITH DENSE FOG DEVELOPING IN THE PANHANDLE...PERSISTING INTO MONDAY LATE MORNING. && .FIRE WEATHER... ISSUED AT 410 PM MDT SUN APR 26 2015 NO FIRE WEATHER CONCERNS THROUGH THE MIDDLE OF THIS WEEK AS A PERIOD OF UNSETTLED WEATHER WILL CONTINUE ACROSS SOUTHEAST WYOMING AND WESTERN NEBRASKA. PERIODS OF RAIN SHOWERS AND HIGH ELEVATION SNOW ARE EXPECTED INTO MONDAY. MUCH DRIER CONDITIONS WILL RETURN BY MIDWEEK WITH DAYTIME RELATIVE HUMIDITIES TRENDING LOWER TOWARDS THE 20 PERCENT RANGE ON WEDNESDAY. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...WINTER WEATHER ADVISORY UNTIL 6 AM MDT MONDAY FOR WYZ114-116. NE...NONE. && $$ SHORT TERM...RJM LONG TERM...GCC AVIATION...GCC FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1149 AM MDT SUN APR 26 2015 .UPDATE... ISSUED AT 1042 AM MDT SUN APR 26 2015 MODERATE RAIN CONTINUES THIS MORNING NEAR THE WYO/COLO/NEB BORDERS WITH LIGHT RAIN ELSEWHERE ACROSS THE PLAINS. AREAS OF FOG WERE ALSO OBSERVED IN STRONG UPSLOPE FLOW ALONG THE CHEYENNE RIDGE FROM SIDNEY TO SUMMIT...WITH PATCHY FOG FURTHER NORTH AS WELL. HAVE NOT RECEIVED ANY REPORTS OF FLOODING ISSUES WITHIN THE AREA OF MODERATE RAIN SO FAR...BUT WILL KEEP AN EYE ON THIS AREA AS PERIODS OF RAIN WILL CONTINUE THIS AFTERNOON. FURTHER WEST ACROSS CARBON AND PORTIONS OF ALBANY COUNTIES...SKIES WERE MOSTLY CLEAR/PARTLY CLOUDY THROUGH THE MORNING. CURRENT WATER VAPOR IMAGERY SHOWS THE NEXT PIECE OF ENERGY MOVING NORTH ACROSS COLORADO...WITH CONVECTION FIRING ALONG THE FRONT RANGE MOUNTAINS AND POINTS TO THE SOUTHEAST. THIS WAVE WILL MOVE NORTH-NORTHWEST THROUGH THE AFTERNOON AND SHOULD FIRE UP ADDITIONAL CONVECTION ACROSS THE PLAINS AS THE CURRENT AREA OF ACTIVITY SHIFTS NORTH...WITH CONVECTIVE RAIN/SNOW SHOWERS EXPECTED ALONG AND WEST OF THE LARAMIE RANGE AS WELL WHERE MID/LLVL LAPSE RATES ARE BETWEEN 6 AND 8 C/KM WITH SOME WEAK INSTABILITY PRESENT. WILL SEE A FEW TSTORMS AS WELL WITHIN THESE AREAS OF CONVECTION. BASED ON THIS MORNINGS SOUNDINGS AND 700 MB TEMPS PROGGED TO DECREASE A DEGREE OR TWO THRU THIS AFTERNOON WITH THE INCOMING WAVE...THINK SNOW LEVELS TODAY WILL HOVER AROUND 8000 FEET ON AVERAGE. THEY COULD DROP TO BETWEEN 7000 AND 7500 FEET IN AREAS OF STRONGER CONVECTION THO. THE MORE PERSISTENT SNOW SHOWERS SHOULD SET UP ACROSS THE MOUNTAINS WITH PERHAPS A BAND OF ACTIVITY EXTENDING FROM THE SOUTHERN LARAMIE RANGE EAST-SOUTHEAST ACROSS THE CHEYENNE RIDGE LATER THIS AFTERNOON. LOOKING AT MODERATE TO HEAVY SNOW RATES IN SHOWERS AND THUNDERSNOW OVER THE MOUNTAINS...INCLUDING THE SOUTHERN LARAMIE RANGE SUMMIT...WITH RAIN FURTHER EAST. THE WINTER WEATHER ADVISORY IS IN GOOD SHAPE FOR NOW...WITH MOST OF THE ACCUMULATIONS EXPECTED THIS AFTERNOON AND EVENING. DEFINITELY CAN SEE SOME CONVECTIVE SNOW REACHING THE VALLEY FLOORS ACROSS ALBANY AND CARBON COUNTIES...WITH SOME ACCUMULATION POSSIBLE ON GRASSY SURFACES AND ROADS NEAR ARLINGTON/ELK MOUNTAIN TO RAWLINS IF HEAVIER SHOWERS/TSTORMS MOVE INTO THESE AREAS. EASTERN PORTIONS OF THE LARAMIE VALLEY...INCLUDING LARAMIE MAY SEE JUST ENOUGH DOWNSLOPE TO KEEP PRECIP CHANCES LOWER BUT WILL KEEP AN EYE ON TRENDS AND WILL UPDATE THE FORECAST AS NEEDED. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 236 AM MDT SUN APR 26 2015 CURRENT FORECAST APPEARS ON TRACK WITH CURRENT KCYS RADAR LOOP SHOWING MODERATE TO LOCALLY HEAVY RAIN ACROSS THE HIGH PLAINS...AND SCATTERED RAIN/SNOW WEST OF THE I25 CORRIDOR. THE MAIN FORECAST CONCERN NOW APPEARS TO BE SNOWLEVELS...WHICH HAVE BEEN LOWER THAN ANTICIPATED FOR EARLY THIS MORNING. THE I80 SUMMIT HAS BEEN REPORTING SNOW AND LOW VISIBILITIES IN HEAVY SNOW FOR THE LAST SEVERAL HOURS. EVEN LARAMIE AIRPORT IS DOWN TO 35 DEGREES AND HEAVY RAIN...SO SNOWLEVELS ARE LIKELY BETWEEN 7500 TO 8000 FEET BY NOW. MODELS CONTINUE TO SHOW THE LARGE AREA OF STRONG UPPER LEVEL DIVERGENCE THROUGH NOON SUNDAY OVER MOST OF THE HIGH PLAINS ACROSS SOUTHEAST WYOMING AND INTO WESTERN NEBRASKA. BELIEVE THIS AREA OF PRECIPITATION CURRENTLY STRETCHING FROM DENVER TO THE SOUTHERN NEBRASKA PANHANDLE WILL EXPAND NORTH AND WEST TODAY. WITH SNOW STARTING TO ACCUMULATE ACROSS THE I80 SUMMIT...ISSUED A WINTER WEATHER ADVISORY FOR THE SOUTHERN LARAMIE RANGE AND SNOWY RANGES THROUGH EARLY MONDAY MORNING. EXPECT 5 TO 10 INCHES OF WET SNOW ACROSS THESE AREAS. ALTHOUGH SNOW ACCUMULATION ON THE ROADS MAY BE LIMITED...BELIEVE THE COMBINATION OF REDUCED VISIBILITIES DUE TO SNOW AND FOG WILL MAKE TRAVEL HAZARDOUS OVER THE I80 SUMMIT. IN ADDITION...ANY ADDITIONAL COOLING AND HEAVY SNOW MAY CREATE SLICK CONDITIONS ABOVE 7500 FEET. DO NOT EXPECT IT TO BE SNOWING ALL THE TIME...WITH PATCHY DENSE FOG IN BETWEEN PERIODS OF SNOWFALL DUE TO MOIST EAST TO SOUTHEAST FLOW. TONIGHT AND MONDAY...MODELS SHOW THE DEFORMATION BAND REMAINING OVER AND JUST EAST OF THE LARAMIE RANGE THROUGH THE NIGHT WITH A CONTINUATION OF LIGHT RAIN AND SNOW. WOULD NOT BE SURPRISED IF SNOWLEVELS LOWER TO AROUND 6000 FEET BY EARLY MONDAY MORNING. THANKFULLY...PRECIP RATES DO NOT APPEAR VERY HIGH WITH THE DEFORMATION BAND...SO EXPECT MINIMAL ACCUMULATIONS BETWEEN 6000 TO 7500 FEET. NOT COMPLETELY CONVINCED THAT THIS STORM WILL SLIP BY TO THE SOUTH AND EAST BY MONDAY DUE TO THE STRONG RIDGE OF HIGH PRESSURE TO OUR EAST. WILL NEED TO CLOSELY MONITOR THIS SYSTEM TO SEE IF IT EVENTUALLY DRIFTS EASTWARD INTO TEXAS. DID NOTE THAT THE NEW GFS RUN HAS THE CENTER OF THE UPPER LOW A BIT FURTHER NORTH...AND ANY NORTHEAST DRIFT WILL RESULT IN MORE PRECIP THROUGH MONDAY. GRADUALLY LOWERED POP THROUGH MONDAY...BUT KEPT A MENTION OF SCATTERED RAIN/SNOW SHOWERS. EXPECT CONDITIONS TO GRADUALLY IMPROVE LATE MONDAY NIGHT AND INTO EARLY TUESDAY MORNING AS THE UPPER LEVEL LOW MOVES INTO THE SOUTHERN PLAINS AND WEAKENS. MODELS INDICATE A HIGH AMPLITUDE RIDGE AXIS MOVING INTO THE ROCKY MOUNTAIN REGION FOR TUESDAY...RESULTING IN TEMPERATURES CLIMBING TO NEAR AVERAGE LEVELS FOR THIS TIME OF THE YEAR. KEPT POP BELOW 10 PERCENT ON TUESDAY WITH HIGHS 60S. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 259 AM MDT SUN APR 26 2015 AFTER SEVERAL DAYS OF UNSETTLED WEATHER...THE EXTENDED FORECAST PERIOD WILL BE WARM AND ON THE DRY SIDE. UPPER RIDGE WILL SHIFT FROM THE PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES BY MID WEEK. WEDNESDAY WILL BE VERY NICE WITH HIGH TEMPERATURES IN THE 60S WEST AND 70S INTO THE PLAINS. WINDS WILL BE LIGHT ALONG WITH MOSTLY CLEAR SKIES. UPPER RIDGE WILL FOLD OVER INTO THE PLAINS BY THURSDAY WITH A SHORT WAVE TROUGH SKIRTING NORTH OF THE FORECAST AREA LATE THURSDAY INTO THURSDAY NIGHT. THE GFS HAS TRENDED TOWARD THE ECMWF WITH THE PASSAGE OF THIS WAVE. A FEW SHOWERS AND THUNDERSTORMS ARE A REMOTE POSSIBILITY OVER HIGHER ELEVATIONS LATE THURSDAY INTO FRIDAY...BUT CURRENTLY THINKING THE MODELS ARE A BIT TOO AGGRESSIVE WITH THE STRENGTH OF THE SHORTWAVE...AS IT WILL LIKELY SHEAR APART AS IT MOVES INTO THE RIDGE. AT ANY RATE...MOST PLACES WILL STAY DRY THURSDAY AND FRIDAY. THURSDAY WILL LIKELY BE THE WARMEST DAY OF THE WEEK WITH BREEZY WEST FLOW SETTING UP OVER THE AREA. DOWNSLOPING WILL CONTRIBUTE TO WARMING ACROSS EASTERN PORTIONS OF THE FORECAST AREA. A BIT COOLER FRIDAY FOLLOWING THE PASSAGE OF A COLD FRONT BUT CURRENTLY EXPECTING THE FRONT TO BE WEAKER THAN THE MODELS ARE DEPICTING SO KEPT HIGH TEMPERATURES ON THE WARM SIDE OF GUIDANCE VALUES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY) ISSUED AT 1150 AM MDT SUN APR 26 2015 IFR TO MVFR ACROSS SOUTHEAST WYOMING AND NEBRASKA PANHANDLE THROUGH THE TAF PERIOD. HRRR GUIDANCE USED FOR THE 18Z TAFS WHICH SHOWS AREAS EAST OF THE LARAMIE RANGE STAYING IFR THROUGH THE LATE AFTERNOON. COULD SEE A LIFT TO MVFR OUT IN THE PANHANDLE FOR KAIA AND KCDR AS THE AFTERNOON PROGRESSES. SHOULD SEE A FAIRLY RAPID DETERIORATION AFTER SUNSET WITH DENSE FOG DEVELOPING IN THE PANHANDLE...PERSISTING INTO MONDAY LATE MORNING. FOG AND LOW CEILINGS WITH RAIN WILL BE PREVALENT EAST OF THE LARAMIE RANGE INTO THE PLAINS OF WESTERN NEBRASKA PANHANDLE WITH DENSE FOG POSSIBLY DEVELOPING LATE TODAY INTO TONIGHT AS PRECIPITATION BECOME LIGHT. LOW CEILINGS AND FOG MAY PERSIST WELL INTO MONDAY FOR SOME AREAS. && .FIRE WEATHER... ISSUED AT 236 AM MDT SUN APR 26 2015 NO FIRE WEATHER CONCERNS THROUGH THE MIDDLE OF NEXT WEEK AS A PERIOD OF UNSETTLED WEATHER WILL CONTINUE ACROSS SOUTHEAST WYOMING AND WESTERN NEBRASKA. PERIODS OF RAIN SHOWERS AND HIGH ELEVATION SNOW ARE EXPECTED INTO MONDAY WITH ISOLATED THUNDERSTORMS POSSIBLE ON SUNDAY. HUMIDITIES WILL TREND MUCH HIGHER THIS WEEKEND WITH RECOVERIES NEAR 90 PERCENT...AND DAYTIME HUMIDITIES BETWEEN 60 TO 80 PERCENT. DAYTIME RELATIVE HUMIDITIES WILL TREND LOWER LATER NEXT WEEK...RANGING BETWEEN 25 TO 35 PERCENT BY THURSDAY AFTERNOON. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...WINTER WEATHER ADVISORY UNTIL 6 AM MDT MONDAY FOR WYZ114-116. NE...NONE. && $$ UPDATE...RJM SHORT TERM...TJT LONG TERM...SML AVIATION...CLH FIRE WEATHER...TJT