Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/20/16


AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1052 AM MDT MON APR 18 2016 .UPDATE... ISSUED AT 1041 AM MDT MON APR 18 2016 TIGHT MID LEVEL CIRCULATION BASICALLY OVER THE GRAND VALLEY HAS SQUEEZED OUT SOME SNOW THIS MORNING. RAP SUGGESTS THIS CIRCULATION REFORMING TO OUR EAST OVER THE ELKS/VAIL PASS AREA BY MID AFTERNOON WITH A CONVERGENT LINE EXTENDING IN THE SOUTHERN MOUNTAINS. THIS LINES UP WITH OUR CURRENT ADVISORY AND EXPECT SOME SNOW RATES TO INCREASE AS INSTABILITY BECOMES MORE RELEVANT WITH HEATING. ADJUSTED HIGHS DOWN UNDER THE LOW AS WE ARE STILL TRAPPED IN THE MID 30S IN THE GRAND VALLEY LATE THIS MORNING. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 401 AM MDT MON APR 18 2016 THE BROAD...QUASI-STATIONARY LOW PRESSURE SYSTEM FROM THIS WEEKEND WILL PERSIST OVER THE AREA IN THE NEAR TERM. THE LATEST SATELLITE IMAGERY OVERLAID WITH RAP13 ANALYSIS PLACED THE LOW CENTER OVER SOUTH-CENTRAL WYOMING EARLY THIS MORNING. MEANWHILE...A LOBE OF VORTICITY MOVING THROUGH THE BASE OF THE LOW CONTINUED TO GENERATE CLOUDS AND LIGHT TO MODERATE SNOW OVER THE SOUTHERN AND CENTRAL MOUNTAINS. MODELS INDICATED SNOWFALL WILL REMAIN PERSISTENT OVER THIS AREA AS A SECOND VORT LOBE COMBINES WITH JET DIVERGENCE AND INSTABILITY FROM LATE MORNING...THROUGH THE AFTERNOON AND INTO THE EVENING. ISOLATED THUNDERSTORMS ARE ALSO POSSIBLE. MODELS SUGGEST SNOWFALL ACCUMULATIONS FROM 4 TO 8 INCHES FOR THE HIGHER ELEVATIONS THROUGH THIS EVENING SO HOISTED A WINTER WEATHER ADVISORY FOR THE WEST ELK...SAWATCH AND SAN JUAN MOUNTAINS ABOVE 9000 FEET. ELSEWHERE PRECIPITATION WILL BE MORE SCATTERED IN COVERAGE WITH CHANCES LOWER WEST OF A BAGGS TO RIFLE TO CORTEZ LINE. THE CENTER OF THE LOW FINALLY SHIFTS EAST OF THE DIVIDE LATE TONIGHT CAUSING SHOWERS TO BECOME MORE SCATTERED AND WEAKER. HOWEVER...A PORTION OF THE AREA WILL RECEIVE A PARTING SHOT FROM THIS STORM TUESDAY DESPITE THE LOW CENTER BECOMING POSITIONED OVER THE EAST-CENTRAL PART OF THE STATE. MOISTURE WRAPPING AROUND THE LOW CENTER WILL SPILL OVER THE NORTHERN AND CENTRAL COLORADO MOUNTAINS AND VALLEYS GENERATING ANOTHER ROUND OF SNOW FOR THE MOUNTAINS. ACROSS THE NORTHWEST PLATEAU AND THE CENTRAL VALLEYS SNOW WILL SHIFT TO RAIN AS SNOW LEVELS RISE TO NEAR 7000 FEET DURING THE AFTERNOON. ELSEWHERE...DRY CONDITIONS WILL PREVAIL WITH MOSTLY CLEAR TO PARTLY CLOUDY SKIES. TEMPERATURES WILL REMAIN WELL BELOW NORMAL AGAIN TODAY WITH LOWS DIPPING CLOSE TO FREEZING IN THE LOWER VALLEYS TONIGHT. A BIT WARMER...BUT STILL BELOW NORMAL TUESDAY AS MILDER AIR FILLS IN BEHIND THE LOW. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 401 AM MDT MON APR 18 2016 TEMPERATURES CONTINUE TO RECOVER CLOSE TO NORMAL WEDNESDAY BUT THEN RISE ABOVE ON THURSDAY AS A RIDGE AMPLIFIES TO OUR WEST THEN BUILDS OVERHEAD. MODEL SOLUTIONS SEPARATE AFTER THE RIDGE SHIFTS EAST ON FRIDAY. THIS LOOKS LIKE A PATTERN SHIFT TO LOWER AMPLITUDE FLOW THAT COULD BE ACTIVE FOR US FOR THE NEXT 10 DAYS OR MORE. FRIDAY BETWEEN THE EASTERN RIDGE AND WEST COAST TROUGH...THE DEEPER GFS PULLS MOISTURE AND SHOWERS INTO THE FORECAST AREA ALL THE WAY UP FROM CENTRAL MEXICO. THE 12Z EC HAS TRENDED DEEPER AND CLOSER TO THE GFS BUT QPF AMOUNTS ARE LESS. THIS WOULD BE A QUITE MILD FLOW WITH AFTERNOON 700MB TEMPS AT 6C OR EVEN WARMER. RAIN EXPECTED AT ALL ELEVATIONS THOUGH CONVECTION COULD PRODUCE NON OR LOW ACCUMULATING SNOW ABOVE TREELINE. THE MILD AND MOIST TROUGH PASSES NEXT SATURDAY INTO SUNDAY... AGAIN WITH SIGNIFICANT DIFFERENCES BETWEEN THE GFS AND EC. ANOTHER PACIFIC LOW APPROACHES EARLY THE NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1052 AM MDT MON APR 18 2016 MID LEVEL CIRCULATION OVER THE GRAND VALLEY WILL GRADUALLY SHIFT EAST TO THE NEAR THE CENTRAL DIVIDE THIS AFTERNOON. SOUTHERLY FLOW AHEAD OF THE LOW KEEPING LOW CLOUDS AND PRECIPITATION IN THE SOUTHERN VALLEYS WITH ANOTHER ARE DIRECTLY UNDER THE LOW. THIS HAS LED TO IFR/MVFR AT KDRO AND KGJT. AS THE LOW SHIFT EAST NORTHERLY FLOW WILL BE MORE OF AN IMPACT AND SHOULD CONTINUE TO IMPACT FLIGHT OPERATIONS AT KASE. KTEX SHOULD ALSO HAVE SOME IMPACTS FROM THE FLOW THIS AFTERNOON WITH IMPROVEMENTS EXPECTED AT KDRO AND KGJT THROUGH THE FIRST SIX HOURS OF THE FORECAST. LESS CONFIDENCE FOR IMPACTS FROM KRIL TO KEGE UNDER THE PATH OF THIS SHIFTING CIRCULATION. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR COZ010- 012-018-019. UT...NONE. && $$ UPDATE...15 SHORT TERM...NL LONG TERM...JOE/NL AVIATION...NL
AREA FORECAST DISCUSSION
NWS ALBANY NY
459 PM EDT MON APR 18 2016 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION TONIGHT WITH SOME CLOUDS AND WIDELY SCATTERED SHOWERS. THIS FRONT WILL PUSH SOUTH TOMORROW ALLOWING FOR SOMEWHAT COOLER WEATHER TO FILTER BACK IN VIA GUSTY NORTHWEST WINDS. IT WILL BE DRY AND PLEASANT FOR THURSDAY WITH THE NEXT CHANCE OF RAIN FOR FRIDAY. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 459 PM EDT...ANOTHER EXCEPTIONAL DAY IN THESE PARTS WITH MOST OF US ENJOYING WALL TO WALL SUNSHINE AND TEMPERATURES WELL INTO THE 70S...TOUCHING AROUND 80 IN A FEW OF THE WARMER SPOTS OF THE MID HUDSON VALLEY. A COLD FRONT STILL WAS SITUATED OVER THE SAINT LAWRENCE VALLEY...ABOUT TO MAKE ITS MOVE SOUTHWARD THIS EVENING...SWEEPING ACROSS ALL OF EASTERN NEW YORK AND ADJACENT WESTERN NEW ENGLAND... BY EARLY TUESDAY. THIS FRONT LOOKS SOMEWHAT MOISTURE STARVED AS IT SLIPS SOUTH INTO OUR REGION VIA A NORTHWESTERLY WIND TONIGHT. THERE WILL BE VERY LITTLE SURFACE CONVERGENCE TO HELP GENERATE LIFT. THE BEST CHANCE OF ANY SHOWERS WILL BE IN THE ADIRONDACKS...BUT EVEN HERE WE DO NOT EXPECT MUCH RAINFALL AT ALL AS THE LATEST 4KM BTV WRF HAS BACKED OFF RAINFALL AMOUNTS EVEN IN THE ADIRONDACKS. THE HRRR HAS A LITTLE MORE BUT NOT MUCH. FURTHER SOUTH IT LOOKS AS IF THERE ONLY BE SPOTTY LIGHT AMOUNTS IF ANY AT ALL. IT WILL BE FAIRLY MILD TONIGHT WITH LOWS GENERALLY IN THE 40S. A LIGHT NORTHWEST WIND WILL INCREASE A BIT TOWARD DAYBREAK. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... THE COLD FRONT SHOULD BE JUST SOUTH OF OUR REGION BY TUESDAY. IN ITS WAKE...THERE COULD BE SOME RESIDUAL CLOUDS...AND PERHAPS ANOTHER SPRINKLE OR TWO...MAINLY ACROSS THE HIGHER TERRAIN. OTHERWISE IT WILL DRY WITH INCREASING SUNSHINE AND A NORTHWEST BREEZE. THE BREEZE COULD GUST TO 30 MPH IN THE USUAL WINDY SPOTS...HIGHER TERRAIN....MOHAWK VALLEY AND CAPITAL REGION. TEMPERATURES WILL BE NOTICEABLY COOLER AS H850 TEMPS COOL TO ABOUT - 2C. HOWEVER...WITH GOOD MIXING VALLEYS LOOK TO CRACK THE 60S...50S HIGHER TERRAIN. THESE VALUES ARE STILL SLIGHTLY ABOVE NORMAL. HIGH PRESSURE WILL BUILD INTO THE REGION TOMORROW NIGHT THROUGH WEDNESDAY. THIS WILL PROVIDE A MAINLY CLEAR SKY AND SLACKENING WINDS. TEMPERATURES WILL TUMBLE TO THE 30S AT NIGHT. THE HIGHS ON WEDNESDAY WILL BE 55 TO 60 ACROSS THE HIGHER TERRAIN...60 TO 65 VALLEYS. WEDNESDAY NIGHT WILL FEATURE ANOTHER CLEAR CALM AND CHILLY NIGHT IN THE 30S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AN UPPER LEVEL RIDGE...STILL IN PLACE FROM EARLIER...BREAKS DOWN ACROSS THE EASTERN CONUS AND ALLOWS FOR THE UPSTREAM CUT OFF LOW TO BECOME ENTRAINED INTO THE NORTHERN POLAR JET FOR THE LATER HALF OF THIS WEEK. THIS WILL BRING INCREASING CLOUDS AND MOISTURE FOR HIGHER POPS THROUGH THURSDAY INTO AT LEAST THE FIRST HALF OF FRIDAY. SHOULD REMAIN RATHER MILD AS H850 TEMPS REMAIN AROUND +10C. IN THE WAKE OF THIS PROGRESSIVE SYSTEM FRIDAY NIGHT AND INTO THE WEEKEND...COLDER AIR ADVECTS INTO THE REGION AS WE RETURN H850 TEMPS BELOW 0C. HOWEVER...WITH HIGH SUN ANGLE THOSE VALLEY TEMPERATURES FOR THE AFTERNOON SHOULD REMAIN INTO THE 50S WITH 40S FOR THE TERRAIN. HOWEVER...OVERNIGHT LOWS WILL DIP BACK INTO THE 30S WITH 20S FOR THE HIGHER TERRAIN. THERE IS SOME DISCREPANCY WITH RESPECT TO MOISTURE QUICKLY ADVECTING INTO THE REGION WITHIN THE REGION OF CONFLUENCE ACROSS THE GREAT LAKES REGION IN THE WAKE OF THE COLD FRONT. THE GFS WOULD IMPLY CHANCE POPS FOR SATURDAY NIGHT INTO SUNDAY WHERE BOUNDARY LAYER TEMPS MAY BE COLD ENOUGH FOR A LITTLE LIGHT SNOW FOR THE HIGHER TERRAIN. THE ARRIVAL OF THE ECMWF ALSO SUPPORTS THE GFS BUT DELAYED ABOUT 12-18 HOURS. FOR NOW...WE WILL INTRODUCE SLIGHT CHANCE POPS THROUGH LATE SATURDAY NIGHT INTO SUNDAY. TEMPERATURES THROUGH THE WEEKEND WILL LIKELY AVERAGE JUST BELOW NORMAL. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... NO AVIATION WEATHER RELATED PROBLEMS THROUGH THE EVENING PEAK WITH VFR...LIGHT WIND AND NO RESTRICTIONS TO VISIBILITY. THEN...A COLD FRONT WILL SLOWLY SLIDE SOUTH WORKING THROUGH THE TAFS LATE EVENING INTO THE OVERNIGHT HOURS. THIS FRONT WILL SPREAD MAINLY VFR CIGS AND PERHAPS A FEW LIGHT SHOWERS. WE DID ASSIGN A PROB30 GROUP FOR A BRIEF REDUCTION TO MVFR AT KGFL BETWEEN 03Z-09Z BUT OTHERWISE LEFT ALL THE TAF SITES AT VFR STATUS. ASSIGNED A VCSH AT KALB AND KPSF DURING THE OVERNIGHT HOURS. THE FRONT WILL SLIP SOUTH...AND MOST CIGS SHOULD BECOME SCATTERED WITH BASES 40-60 (FEW AT KPOU) AROUND OR SHORTLY AFTER 12Z. A LIGHT AND VARIABLE WIND THROUGH THE EVENING AROUND 5KTS...SHIFTING TO THE NORTH OR NORTHWEST OVERNIGHT WITH THE FRONTAL PASSAGE...AND INCREASING TO 8-12KTS LATER BY TUESDAY. GUSTS WILL INCREASE TO AROUND 20KTS (HIGHEST AT KPSF AND KALB)...BY MIDDAY. OUTLOOK... TUESDAY NIGHT TO WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. FRIDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ...A FIRE WEATHER WATCH HAS BEEN ISSUED FOR ALL OF EASTERN NEW YORK AND ADJACENT WESTERN NEW ENGLAND FROM 100 PM TO 600 PM EDT ON TUESDAY... ...LOW RELATIVE HUMIDITIES IN THE 15-25 PERCENT RANGE ON WEDNESDAY AFTERNOON... THERE HAS NOT BEEN SIGNIFICANT RAINFALL FOR OVER FIVE DAYS. A COLD FRONT WILL CROSS THE REGION TONIGHT BUT WILL LIKELY NOT BRING A QUARTER INCH OF RAINFALL TO REALLY ANY OUR REGION. THERE MIGHT BE A TENTH OF AN INCH ACROSS PORTIONS OF THE ADIRONDACKS...WITH ONLY A FEW HUNDREDTHS EXPECTED ELSEWHERE. TOMORROW...THE WIND WILL INCREASE OUT OF THE NORTHWEST TO 10-15 MPH...GUSTING TO AROUND 25-30 MPH...HIGHEST ACROSS THE MOHAWK VALLEY...HIGHER TERRAIN AND CAPITAL REGION. RH VALUES LOOK TO DROP TO AROUND 30 PERCENT OR LESS. PER COORDINATION WITH OUR MAIN FIRE WEATHER USERS...WE ISSUED A FIRE WEATHER WATCH AGAIN FOR ALL AREAS...INCLUDING ADJACENT WESTERN NEW ENGLAND. THE WINDS WILL RELAX BACK DOWN TO AROUND 5 MPH OVERNIGHT MONDAY...ALLOWING FOR A NEARLY FULL RECOVERY. ON WEDNESDAY...THE WIND SHOULD LIGHTER...FROM THE NORTHWEST...5-15 MPH. RELATIVE HUMIDITIES HOWEVER ONCE AGAIN WILL DROP TO VERY LOW LEVELS... 15-25 PERCENT. BY THURSDAY...AS HIGH PRESSURE BEGINS TO MOVE EAST...ALLOWING FOR A SOUTHERN BREEZE 5-15 MPH. AT THIS POINT...AFTERNOON RH VALUES LOOK A LITTLE HIGHER THAN PREVIOUS DAY...DROPPING TO THE 30S. THE NEXT CHANCE FOR SIGNIFICANT RAINFALL LOOKS TO BE FRIDAY. && .HYDROLOGY... NO HYDROLOGIC CONCERNS THROUGH THE REMAINDER OF THE WEEK. A COLD FRONT WILL PASS THROUGH THE REGION FOR TONIGHT WITH SOME LIGHT RAIN SHOWERS. MOST AREAS WILL ONLY SEE A TENTH OF AN INCH OR LESS. DRY WEATHER WILL RETURN FOR TUESDAY THROUGH THURSDAY. SOME ADDITIONAL RAIN SHOWERS ARE POSSIBLE FOR THURSDAY NIGHT INTO FRIDAY. AS A RESULT...RIVER AND STREAM LEVELS WILL GENERALLY HOLD STEADY OR SLOWLY FALL THROUGH THE WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...FIRE WEATHER WATCH TUESDAY AFTERNOON FOR CTZ001-013. NY...FIRE WEATHER WATCH TUESDAY AFTERNOON FOR NYZ032-033-038>043- 047>054-058>061-063>066-082>084. MA...FIRE WEATHER WATCH TUESDAY AFTERNOON FOR MAZ001-025. VT...FIRE WEATHER WATCH TUESDAY AFTERNOON FOR VTZ013>015. && $$ SYNOPSIS...HWJIV NEAR TERM...HWJIV SHORT TERM...HWJIV LONG TERM...BGM AVIATION...HWJIV FIRE WEATHER...HWJIV HYDROLOGY...FRUGIS/HWJIV
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1017 AM EDT MON APR 18 2016 .SYNOPSIS... HIGH PRESSURE WILL BRING WARM TEMPS INLAND AND COOLER TEMPS NEAR THE SHORELINE THANKS TO SEA BREEZES TODAY. WEAK LOW PRESSURE MOVES THROUGH TONIGHT INTO TOMORROW WITH LIGHT RAIN FOR SOME AND CLOUDS LINGERING INTO THE DAY TOMORROW. HIGH PRESSURE BUILDS OVER THE REGION WEDNESDAY AND THURSDAY. ANOTHER COLD FRONT SWEEPS ACROSS NEW ENGLAND FRIDAY OR SATURDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1017 AM UPDATE... ADJUSTED TEMPERATURES SLIGHTLY HIGHER BASED ON OBSERVED TRENDS. MOST OF THE RAPIDLY UPDATING GUIDANCE WAS NOT HANDLING TEMPERATURES WELL...WITH MOST ABOUT 5 DEGREES TOO LOW FROM CURRENT OBSERVATIONS. THE LATEST HRRR LOOKED TO HAVE A VERY GOOD HANDLE ON TRENDS...BUT ITS TIMING MIGHT BE AN HOUR TOO FAST. THE HRRR BRINGS THE SEABREEZE ALL THE WAY WEST PAST WORCESTER THIS AFTERNOON. UPDATED WINDS USING THE HRRR. TEMPERATURES SHOULD RISE WELL INTO THE 70S ACROSS THE INTERIOR. MOST OF THE COASTAL PLAIN WILL REMAIN IN THE 60S...WITH EVEN SOME 50S ACROSS OUTER CAPE COD AND PORTIONS OF CAPE ANN. PREVIOUS TIMING OF CLOUDS STILL LOOKS TO BE ON TRACK...SO NO CHANGES THERE. PREVIOUS DISCUSSION... WHILE THE LAST FEW MORNINGS WERE ALL NEARLY SKC...THIS ONE WILL BE TAINTED BY A FEW CI IN THE WEAK WARM ADVECTION IN ADVANCE OF THE BACKDOOR COLD FRONT APPROACHING FROM NRN NEW ENGLAND AND QUEBEC. STILL...SEVERAL OF THE TYPICALLY COLD SPOTS ARE IN THE MID 30S WHILE THE REST OF THE REGION IS COMFORTABLY IN THE LOW 40S. WITH THESE MINS BEING A BIT MORE MILD THAN PREVIOUS NIGHTS...AND PLENTY OF FILTERED SUNSHINE THROUGH THE BUILDING CI WITH BREAKS...EXPECT TEMPS TO ONCE AGAIN OVER-ACHIEVE TODAY FOR MANY LOCATIONS. H85 TEMPS WILL APPROACH +9C WITH H92 NEAR +12C OVER THE INTERIOR WHILE THE ERN HALF OF THE REGION IS COOLED...BUT MORE ON THAT BELOW. THIS SHOULD ALLOW AREAS THAT REACHED THE MID 70S YESTERDAY TO MAKE A RUN CLOSE TO 80F THANKS TO THE LACK OF VEGETATION AND ALL INSOLATION BEING USED FOR WARMING. THE ERN HALF OF THE REGION WILL BE UNDER THE INFLUENCE OF A DECENT EASTERLY SEA BREEZE FRONT...THANKS TO VERY WEAK PRES GRADIENT WITH HIGH PRES CRESTING ACROSS THE AREA. EXPECTED TO START AROUND 14Z /9AM LOCAL/ AND GRADUALLY MOVE FURTHER INLAND INTO THE AFTERNOON HOURS...AIDED BY GRADIENT WIND PROFILE SHIFTING FROM E-W THANKS TO HIGH PRES MOVING E OF THE REGION. THEREFORE...NEAR SHORE LOCATIONS WILL WILL STRUGGLE TO BREAK INTO THE 60S BEFORE COOLING BEGINS WHILE AREAS FURTHER INLAND MAY MAKE A RUN TOWARD 70F BY MID DAY BEFORE COOLING AS WELL. REGARDING THE MARATHON ROUTE...BY THE 9AM PERIOD...AREAS BETWEEN 495 AND 128 SHOULD BE APPROACHING THE UPPER 50S TO LOWER 60S AND WARMING TO NEAR 70 BY MID DAY. AREAS WITHIN 128 INCLUDING THE BACK BAY FINISH LINE MAY ONLY MAKE IT TO THE MID 60S BY MID DAY BEFORE COOLING BEGINS AND CONTINUES INTO THE LATE AFTERNOON...BY WHICH TIME TEMPS MAY HAVE DROPPED INTO THE 50S. NO RAIN EXPECTED TODAY...THE DEVELOPMENT OF A CLOSE LOW PRES WAVE WILL SLOW PROGRESSION OF PRECIP SHIELD UNTIL THE OVERNIGHT HOURS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... TONIGHT... AS MENTIONED ABOVE...WEAK LOW PRES WAVE WILL TRAVERSE THE APPROACHING COLD FRONT EXPECTED TO SLIDE THROUGH THE REGION DURING THE EARLY AM HOURS. THIS FEATURE IS MOISTURE STARVED...BUT NOTING ENOUGH MOISTURE IN THE COLUMN TO SQUEEZE OUT A TENTH OR LESS OF LIGHT RAIN AS IT PASSES MAINLY N OF THE MASS PIKE BETWEEN 02Z AND 12Z BEFORE DRIER AIR SPILLS OVER INTO THE MID MORNING HOURS. THE INCREASED CLOUD COVER WITH THIS FEATURE WILL LIMIT LOWS ONLY IN THE LOW 40S...MORE MILD THAN PREVIOUS NIGHTS. TOMORROW... UPPER LVL JET STREAK/S POLEWARD ENTRANCE REGION WILL GRADUALLY SHIFT E OF THE REGION THROUGH THE DAY...ALONG WITH ATTENDANT WEAK LOW PRES WAVE. GRADUAL PRECIP END THROUGH MID MORNING GIVING WAY TO A FEW SPOTS OF DRIZZLE POSSIBLE THANKS TO DRYING SUBSIDENCE ALOFT BEFORE LOW LVLS FULLY CLEAR. GRADUAL CLEARING FROM W-E WILL ALLOW FOR SUNSHINE IN THE AFTERNOON ACROSS THE CT VALLEY...BUT IT MAY TAKE UNTIL EARLY EVENING FOR THE ERN HALF OF THE REGION TO SEE CLEARING. H85 TEMPS NEARING +2C WILL BE NEARLY FULLY MIXED TO IN THE W AS CLEARING OCCURS SO HIGHS COULD REACH THE MID 60S THERE...MEANWHILE THE E WILL LIKELY ONLY TOP OUT IN THE 50S THANKS TO LIMITED MIXING UNDER CLOUDY SKIES. MOST MOS GUIDANCE TOO WARM IN THE E...SO LEANED CLOSER TO THE ECMWF 2M TEMPS WITH THIS UPDATE. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... BIG PICTURE... LONGWAVE PATTERN RESOLVES INTO RIDGE-WEST/TROUGH-EAST DURING THIS PERIOD. THIS WILL FAVOR A COUPLE OF COLD FRONTAL PASSAGES DURING THE NEXT SEVEN DAYS WITH AIRMASSES FROM NORTHERN CANADA TRAILING EACH FRONT. BRIEF WARMUP POSSIBLE BETWEEN THE TWO FRONTS. CLOSED LOW OVER THE ROCKIES THAT SUPPORTED SNOW THERE OVER THE WEEKEND WILL OPEN UP MIDWEEK AND EJECT EAST...MERGING WITH A NORTHERN STREAM SHORTWAVE. THIS COMBINED SYSTEM WILL MOVE ACROSS NEW ENGLAND AT THE END OF THE WEEK. MAIN DIFFERENCE BETWEEN THE MODELS IS THAT THE GFS MORE FULLY PHASES THE COMBINED SYSTEM WHILE THE CANADIAN AND ECMWF SHOWS A LINGERING SOUTHERN LOBE IN THE TROUGH THAT MOVES ACROSS THE CENTRAL APPALACHIANS/MID ATLANTIC FRIDAY NIGHT. PARTLY AS A RESULT THE GFS IS FASTER THAN THE OTHERS IN BRINGING THE SYSTEM THROUGH NEW ENGLAND. THE GFS VERSION WOULD SUGGEST A CLEAN COLD FROPA WHILE THE CANADIAN/ECMWF VERSION WOULD SUGGEST A TRAILING WAVE DEVELOPING ALONG THE FRONT. WHILE THERE IS CONFIDENCE IN SHOWERS OCCURRING THE END OF THE WEEK...THE DETAILS AND TIMING OF OCCURRENCE REMAIN IN QUESTION. WE FAVORED THE SLOWER MORE SELF-CONSISTENT ECMWF SOLUTION...THE GFS IS SOMETHING OF A FAST OUTLIER AMONG THE VARIOUS SOLUTIONS. THE DAILIES... TUESDAY NIGHT THROUGH THURSDAY... HIGH PRESSURE BUILDS OVER THE REGION WITH FAIR DRY WEATHER. A NORTH FLOW ON WEDNESDAY SHOULD MAINTAIN LOW DEW POINTS IN THE MID TEENS TO MID 20S. THESE ARE NOT EXTREME VALUES PER LOCAL DEW POINT CLIMATOLOGY BUT LOW ENOUGH TO BE CONSIDERED DRY. AS THE HIGH SHIFTS OFFSHORE AND THE FLOW BECOMES SOUTHWEST...DEW POINTS SHOULD CLIMB INTO THE 30S. TEMPS AT 850 MB 0 TO -2C ON WEDNESDAY AND 6-8C ON THURSDAY SUGGEST MAX SFC TEMPS IN THE 50S TO AROUND 60 WEDNESDAY AND MID 60S TO LOW 70S THURSDAY. FRIDAY THROUGH SUNDAY... EJECTING SHORTWAVE FROM THE ROCKIES SPREADS CLOUDS INTO SOUTHERN NEW ENGLAND BY FRIDAY. MODEL QPF SHOWS DIFFERENCES. THE GFS HAS MEASURABLE QPF IN OUR AREA THURSDAY EVENING WHILE THE GGEM AND ECMWF WAIT UNTIL FRIDAY MORNING. WE FAVOR THE SLOWER SOLUTIONS AT THIS TIME AND SO ADJUSTED POPS TO REFLECT THIS TIMING. CHANCE POPS ALL AREAS. COLD FROPA OVERNIGHT FRIDAY NIGHT. ENDING TIME OF POPS WILL DEPEND ON THE POTENTIAL DEVELOPMENT OF A TRAILING LOW ALONG THE FRONT AS NOTED ABOVE. A CLEAN FRONTAL PASSAGE WOULD END POPS BEFORE SUNRISE WHILE A FRONTAL WAVE WOULD SLOW FRONTAL PROGRESS AND DELAY THE END OF POPS UNTIL SOMETIME SATURDAY. WE WILL SHOW CHANCE POPS ON SATURDAY...JUST IN THE MORNING N AND W OF I-95. THIS TIMING WILL BE ADJUSTED AS THE MODEL DISAGREEMENTS NOTED EARLIER ARE RESOLVED. HIGH PRESSURE THEN BUILDS IN WITH DRIER WEATHER SATURDAY NIGHT AND SUNDAY. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH TUESDAY/... TODAY...HIGH CONFIDENCE. VFR. SEA BREEZES ALREADY STARTING. EXPECTING WINDS TO SHIFT MORE EAST AND INCREASE SLIGHTLY FOR THIS AFTERNOON ALONG THE EAST COAST. A SEABREEZE FRONT PUSHES WELL WEST BY LATE TODAY...AND SHOULD STOP JUST WEST OF KFIT-KORH. LIGHT AND VARIABLE WINDS ELSEWHERE ACROSS SOUTHERN NEW ENGLAND. TONIGHT INTO TOMORROW...MODERATE CONFIDENCE...MAINLY DUE TO TIMING. SOME MVFR IN LOW CIGS AND OCCASIONAL SHRA POSSIBLE NORTH OF A LINE FROM ORE-ORH-PYM...THIS MAINLY BETWEEN 03Z AND 12Z. CONDITIONS IMPROVE TO VFR PRETTY MUCH EVERYWHERE MID MORNING. SHOWERS ENDING AND SKIES DISSIPATING. WINDS SHIFT FROM THE E BACK TO THE N-NW. KBOS TAF...HIGH CONFIDENCE. KBDL TAF...HIGH CONFIDENCE. OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...MODERATE-HIGH CONFIDENCE. VFR THROUGH THE PERIOD. BRIEF MVFR CIGS/VSBYS IN SHOWERS POSSIBLE FRIDAY. NORTH NORTHWEST WINDS MAY GUST TO 25 KNOTS TUESDAY NIGHT AND WEDNESDAY MORNING. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE. TODAY... WINDS GRADUALLY WILL SHIFT TO THE E TODAY...BUT REMAIN LIGHT AND BELOW THE 25 KT THRESHOLD. SEAS CONTINUE TO DISSIPATE SUCH THAT ALL SMALL CRAFT ADVISORIES SHOULD BE LET GO BY EVENING. TONIGHT AND TOMORROW... WEAK LOW PRES MOVES OVER THE WATERS...SOME RAIN/FOG MAY LIMIT INSTABILITY...BUT THIS SYSTEM IS WEAK AND WINDS NOT EXPECTED TO BE A FACTOR. ONLY ISSUE WILL BE A SHIFT TO THE N DURING THE DAY ON TUE. DUE TO THE WEAK PRES FALL AND WINDS...SEAS SHOULD REMAIN BELOW SMALL CRAFT THRESHOLDS THROUGH THE PERIOD. OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...MODERATE-HIGH CONFIDENCE... TUESDAY NIGHT-WEDNESDAY... NORTH-NORTHWEST WINDS MAY GUST TO 25 KNOTS TUESDAY NIGHT AND WEDNESDAY MORNING WITH 5 TO 7 FOOT SEAS MAINLY ON THE OUTER WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED. THURSDAY-FRIDAY... INCREASING SOUTHWEST WINDS AHEAD OF AN APPROACHING COLD FRONT FRIDAY. THIS MAY BUILD SEAS WITH 5 TO 8 FOOT HEIGHTS FRIDAY...BEST CHANCE ON THE EXPOSED SOUTHERN WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR SEAS FRIDAY. && .FIRE WEATHER... TODAY... WINDS LIGHTER STILL TODAY...SHIFTING TO THE E LATE. HOWEVER...WARMER CONDITIONS AND ONLY A SLIGHT RISE IN DEWPOINTS MEAN MINIMUM RH VALUES WILL DROP TO THE TEENS IN CT AND WEST OF THE WORCESTER HILLS. RH VALUES WILL BE HIGHER ALONG EAST COASTAL MA AND RI...MAINLY IN THE 20-40 PERCENT RANGE THANKS TO SEA BREEZE DEVELOPMENT. WILL CONTINUE WITH SPS AS DECIDED YESTERDAY...MAINLY DUE TO THE LOW RH VALUES. TONIGHT AND TUESDAY... MUCH COOLER WEATHER ALONG WITH A PERIOD OF STEADY RAIN TONIGHT NORTH OF THE MASS PIKE ESPECIALLY. RH VALUES NOT AS LOW ON TUE EVEN AS WINDS SHIFT TO THE N AND SKIES CLEAR...ALLOWING TEMPS TO RISE ACROSS WRN MA/CT. MAINLY 30-40 PERCENT MIN RH VALUES EXPECTED...ALTHOUGH NORTHERLY WINDS COULD BY GUSTY OUT OF THE N BY LATE AFTERNOON...20-30 MPH. WEDNESDAY-THURSDAY... TEMPERATURES WILL BE WARMER EACH DAY...REACHING THE 60S AND AROUND 70 INLAND. WARMING AIR AND LOW DEW POINTS WILL MEAN LOW RH VALUES. EXPECT INTERIOR VALUES OF 20-25 PCT WEDNESDAY AND 25-30 PCT THURSDAY. COASTAL VALUES WILL BE 30-45 PCT EACH DAY. THE DEVELOPING WARMTH AND DRYNESS WILL NEED TO BE MONITORED. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM EDT TUESDAY FOR ANZ250-254-255. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 PM EDT THIS EVENING FOR ANZ251. && $$ SYNOPSIS...WTB/DOODY NEAR TERM...BELK/DOODY SHORT TERM...DOODY LONG TERM...WTB AVIATION...WTB/BELK/DOODY MARINE...WTB/DOODY FIRE WEATHER...STAFF
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
128 AM EDT MON APR 18 2016 .AVIATION... VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS UNDER NORTHEAST WINDS...AT TIMES BECOMING GUSTY. && .PREV DISCUSSION... /ISSUED 936 PM EDT SUN APR 17 2016/ UPDATE (REST OF TONIGHT THROUGH MONDAY)... 01Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW A HIGHLY AMPLIFIED UPPER LEVEL PATTERN IN PLACE OVER THE CONUS THIS EVENING. THE STUBBORN OMEGA BLOCK PATTERN REMAINS WITH LARGE SCALE RIDGING OVER THE EASTERN HALF OF THE NATION...ANCHORED ON BOTH SIDES BY LARGE CLOSED LOWS SPINNING OVER THE INTER-MOUNTAIN WEST AND OVER THE WESTERN ATLANTIC. ENERGY ROUNDING THE LOW/TROUGH OVER THE ROCKIES CONTINUES TO SUPPORTS ROUNDS OF HEAVY RAINFALL ACROSS THE CENTRAL AND SOUTHERN PLAINS. THE WEATHER IS MUCH QUIETER OVER THE FLORIDA PENINSULA WHERE WE ARE PROTECTED UNDER THE EASTERN UPPER RIDGE. THE ATMOSPHERIC COLUMN DRIED OUT QUITE A BIT TODAY...WITH MOST OF THE DEEP MOISTURE NOW SHIFTED WELL SOUTH TOWARD THE FLORIDA STRAITS PER EVENING WATER VAPOR IMAGERY. STRONG SURFACE HIGH PRESSURE RIDGING IN FROM THE NORTH IS NOW FULLY IN CONTROL OF FLORIDA THROUGH THE LOWER LEVELS PROVIDING A TIGHT GRADIENT AND BREEZY EAST TO NORTHEAST WINDS. THE GUSTY WINDS WILL DIMINISH SOMEWHAT OVERNIGHT (FOR THE LAND ZONES)...BUT THEN INCREASE ONCE AGAIN WITH DIURNAL MIXING ON MONDAY. WINDS WILL BE INCREASING OVERNIGHT ACROSS THE COASTAL WATERS WITH CAUTIONARY HEADLINES IN THE FORECAST. STACKED RIDGING WILL KEEP OUR FORECAST DRY AND SEASONABLE THROUGH THE EARLY PORTION OF THE WORK WEEK. RAIN CHANCES ARE NEAR ZERO AND TEMPERATURES WILL BE RISING TO AROUND 80 NORTH OF I-4 MONDAY AFTERNOON AND INTO THE LOWER 80S FURTHER SOUTH. MORE OF THE SAME FOR TUESDAY...WITH LESS GUSTY CONDITIONS DURING THE DAY...AND PERHAPS A NEXT DEGREE OR TWO HIGHER FOR AFTERNOON TEMPERATURES. MARINE... A STRONG RIDGE OF HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN OVER THE EASTERN GULF THROUGH MONDAY BEFORE THE HIGH CENTER SETTLES INTO THE SOUTHEASTERN CONUS BY WEDNESDAY. ELEVATED EASTERLY FLOW TO CAUTIONARY LEVELS CAN BE EXPECTED FOR ALL MARINE ZONES OVERNIGHT INTO EARLY MONDAY MORNING. A DECREASE IN THE WINDS MONDAY AFTERNOON MAY BE FOLLOWED BY ANOTHER PERIOD OF CAUTIONARY LEVEL WINDS MONDAY NIGHT FOR PARTS OF THE WATERS. THE PROXIMITY OF THE HIGH PRESSURE CENTER SHOULD THEN PREVENT HEADLINE CRITERIA WINDS AND SEAS THROUGH THE MIDDLE PORTION OF THE WEEK. && .PRELIMINARY POINT TEMPS/POPS... TPA 83 63 82 64 / 0 0 0 0 FMY 84 61 84 61 / 10 0 0 10 GIF 80 60 83 61 / 10 0 0 10 SRQ 83 60 81 62 / 0 0 0 10 BKV 81 54 83 56 / 0 0 0 10 SPG 82 65 82 67 / 0 0 0 0 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ AVIATION...18/FLEMING
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
923 PM CDT TUE APR 19 2016 .UPDATE... 855 PM CDT FRONTAL BOUNDARY BEGAN TO SAG SOUTH ACROSS NORTHERN IL/NORTHWEST IN EARLIER TODAY AND RESULTED IN A WIND SHIFT FROM THE SOUTH/SOUTHWEST TO NORTH/NORTHEAST...COUPLED WITH MUCH COOLER AIR FLOWING INTO NORTHERN IL. TEMPERATURES QUICKLY FELL INTO THE LOW/MID 50S...MEANWHILE SOUTH OF THE BOUNDARY TEMPERATURES WERE HOLDING IN THE 70S. THE BOUNDARY HAS PUSHED SOUTH OF THE FORECAST AREA INTO CENTRAL IL TONIGHT...AND IS EXPECTED TO BECOME STATIONARY OVERNIGHT. SCATTERED SHOWERS ACROSS NORTHWEST IL HAVE STEADILY DIMINISHED IN COVERAGE AND INTENSITY...AND LATEST HI-RES FORECAST GUIDANCE CONTINUES TO LEAN TOWARDS PRECIP COMING TO AN END OVERNIGHT THROUGH DAYBREAK WED. WITH HIGH PRESSURE POSITIONED OVER LOWER MICHIGAN TO JAMES BAY...THIS MAY ALLOW FOR SOME POCKETS OF DRIER AIR AND LESS CLOUD COVER OVERNIGHT...BUT ANY BREAKS WILL BE SHORT LIVED. A WEAK SHORT WAVE IS PROGGED TO DEVELOP OVER THE CENTRAL PLAINS LATE TONIGHT AND WILL HELP TO ENERGIZE THE FRONTAL BOUNDARY...LIFTING THE BOUNDARY BACK NORTH WEDNESDAY AND BRINGING AN INCREASING CHANCE FOR PRECIP BY MID-MORNING. TIMING OF THE FRONTAL BOUNDARY WED WILL DICTATE HIGH TEMPS...BUT CURRENTLY EXPECTING HIGHS TO PUSH BACK INTO THE UPPER 60S TO LOW 70S. THE BETTER CHANCE FOR SHOWERS AND POSSIBLY THUNDERSTORMS WILL ARRIVE IN THE WED AFTERNOON TIMEFRAME. BEACHLER && .SHORT TERM... 236 PM CDT THROUGH TODAY... FOR THE REMAINDER OF THE AFTERNOON AND INTO THE EVENING...THE MAIN FOCUS WILL BE PCPN EXTENT AND TEMPERATURE DISTRIBUTION. AS OF 230PM CDT...WITH A WEAK TROUGH OF LOW PRESSURE ACROSS THE MISSOURI VALLEY AND STRONG HIGH PRESSURE OVER THE UPPER GREAT LAKES...ALONG WITH A WEAK FRONTAL BOUNDARY ROUGHLY ALONG THE ILLINOIS AND KANKAKEE RIVER VALLEYS...THERE HAS BEEN QUITE A SPREAD IN TEMPERATURES ACROSS THE REGION. WITH PREVAILING NORTHEASTERLY FLOW OFF OF THE COOL WATERS OF LAKE MICHIGAN NORTH OF THE BOUNDARY...AND SOUTHERLY FLOW TO THE SOUTH...TEMPERATURES ACROSS THE SOUTHERN PORTIONS OF THE CWA ARE IN THE MIDDLE TO UPPER 70S...WITH SOME LOCATIONS POSSIBLY SEE 80F AGAIN TODAY. HOWEVER...NORTH OF THE BOUNDARY...TEMPERATURES ARE MUCH LOWER...WITH HIGHS TODAY TOPPING OUT ONLY IN THE LOWER 50S. A FEW LAKEFRONT LOCATIONS MAY ONLY SEE TEMPS REACH THE UPPER 40S. PERSISTENT RAIN HAS BEEN FALLING OVER MUCH OF NWRN IL...WITH THE MOST WIDESPREAD RAIN INVOF A VORT MAX SLOWLY LIFTING NEWD. EXPECT THAT THE VORT WILL EVENTUALLY LIFT INTO WISCONSIN AND PCPN CHANCES SHOULD DIMINISH THROUGH THE NIGHT. WHILE THERE WILL STILL BE SOME RESIDUAL CHANCE FOR SOME SHOWERS OVERNIGHT ...ESPECIALLY WEST OF THE I-39 CORRIDOR...NERN IL AND NWRN IN SHOULD REMAIN DRY. HOWEVER...THERE IS A CHANCE FOR AN ISOLD SHOWER THROUGH THIS EVENING OVER THE CHICAGO METRO AREA. WITH A RELATIVELY MOIST AIRMASS AND THICK CLOUD COVER EXPECTED TO REMAIN IN PLACE OVERNIGHT...TEMPERATURES SHOULD REMAIN RELATIVELY MILD. OVERNIGHT LOWS ACROSS THE AREA SHOULD RANGE FROM THE UPPER 50S OVER THE PONTIAC METRO AREA TO THE UPPER 40S TO LOWER 50S OVER THE REMAINDER OF THE AREA. KREIN && .LONG TERM... 308 PM CDT WEDNESDAY THROUGH FRIDAY... LINGERING SHOWER CHANCES WILL REMAIN WEDNESDAY MORNING PRIMARILY ACROSS NORTHERN ILLINOIS...WHILE WEAK ENERGY CONTINUES TO LIFT NORTH OUT AHEAD OF APPROACHING LARGE UPPER LEVEL SYSTEM OVER THE PLAINS. HOWEVER...COVERAGE/DURATION WILL REMAIN LOW WITH THIS WEAK ASCENT...AND SO HAVE KEPT POPS LOW DURING THIS TIME. SLOWLY INCREASE POPS THROUGH MIDDAY AND EARLY AFTERNOON WEDNESDAY AS THIS SYSTEM WORKS ITS WAY EAST AND WHILE STRONGER ENERGY WRAPS AROUND THIS SYSTEM. THIS WILL OCCUR AS FRONTAL BOUNDARY LIFTS NORTH THROUGH THE CWA AND WITH DEWPOINTS REBOUNDING BACK INTO THE 50S. THIS SHOULD ALLOW COVERAGE OF SHOWERS TO INCREASE OVER MUCH OF NORTHERN ILLINOIS...ESPECIALLY BY THE LATE AFTERNOON TIME FRAME. INSTABILITY WILL INCREASE DURING THE AFTERNOON BUT WILL REMAIN ON THE LOW SIDE. HOWEVER...WITH INCREASING FORCING ALOFT...DO THINK THUNDERSTORM CHANCES WILL REMAIN. DO THINK TEMPS WILL REBOUND ACROSS THE CWA ON WEDNESDAY WITH BOUNDARY LIFTING NORTH...SO RAISED HIGH TEMPS WITH MOST LOCATIONS GETTING INTO THE UPPER 60S WITH THE EXCEPTION OF AREAS NEAR THE LAKE IN NORTHEAST ILLINOIS. PUSH OF PRECIP WEDNESDAY AFTERNOON WILL CONTINUE TO LIFT NORTHEAST THROUGH THE EARLY EVENING AS THIS ENERGY PUSHES THROUGH. SYSTEM WILL BECOME MORE STACKED DURING THE NIGHT WITH THE SURFACE LOW WEAKENING AS IT MOVES INTO THE CWA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING. THIS SHOULD ALLOW FOR COVERAGE OF ANY PRECIP TO LOWER WITH A DRY PERIOD POSSIBLE FOR MOST AREAS. HOWEVER...THIS UPPER LEVEL TROUGH WILL QUICKLY OPEN UP AS IT SWINGS THROUGH THE CWA ON THURSDAY. LINGERING HIGHER DEWPOINTS ALONG SURFACE TROUGH AXIS WITH THIS ADDITIONAL FORCING WILL ALLOW FOR ADDITIONAL SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TO DEVELOP BY LATE THURSDAY MORNING INTO THE AFTERNOON. GIVEN THE ANTICIPATED COVERAGE AT THIS TIME DID NOT RAISE POPS TOO HIGH...BUT COULD SEE THEM RAISED FURTHER WITH LATER FORECASTS. THIS PRECIP IS EXPECTED TO DIMINISH AS IT EXITS TO THE EAST THURSDAY EVENING WITH THE DEPARTURE OF THIS SYSTEM. DID LEAVE A SLIGHT CHANCE FOR SHOWERS THURSDAY NIGHT AS SOME ISOLATED DEVELOPMENT COULD OCCUR ALONG SOUTHWARD DRIFTING BOUNDARY. BUILDING HIGH PRESSURE WILL THEN BRING PERIOD OF DRY WEATHER TO THE AREA FRIDAY. FRIDAY NIGHT THROUGH TUESDAY... QUIET AND NEAR TO SLIGHTLY ABOVE LATE APRIL NORMAL TEMPERATURES WILL BE IN STORE TO START THE WEEKEND. EXPECTING HIGHS IN THE MID TO UPPER 60S INLAND ON SATURDAY. WITH HIGH PRESSURE NEARBY...WINDS SHOULD STAY ONSHORE FOR AT LEAST THE ILLINOIS SHORE KEEPING TEMPERATURES IN THE 50S THERE. ATTENTION WILL THEN TURN TO A MID/UPPER TROUGH EJECTING INTO THE CENTRAL AND NORTHERN PLAINS ON SUNDAY AND SHEARING OUT EARLY NEXT WEEK. THE ASSOCIATED SURFACE LOW FROM THIS TROUGH WILL HAVE A QUASI-STATIONARY FRONTAL BOUNDARY EXTENDING EASTWARD FROM IT SUNDAY AND MONDAY UNTIL THE BOUNDARY POTENTIALLY SHIFTS SOUTH OF THE AREA BY TUESDAY. THIS WILL HAVE AN IMPACT ON OUR SENSIBLE WEATHER CONDITIONS WITH RESPECT TO TEMPERATURES AND PRECIPITATION CHANCES. A DISTURBANCE RIDING OVER THE TOP OF THE MID/UPPER RIDGE OVER THE AREA COULD RESULT IN PRECIP CHANCES RETURNING LATE SATURDAY NIGHT INTO SUNDAY. THEN CONVERGENCE ALONG THE QUASI- STATIONARY FRONT AND ADDITIONAL WAVES EMANATING FROM THE WEAKENING TROUGH COULD BRING A FEW ADDITIONAL ROUNDS OF SHOWERS INTO MONDAY AND A FINAL WAVE NORTH OF THE SOUTHWARD SINKING FRONT ON TUESDAY. MAINTAINED CHANCE POPS FROM BLENDED INITIALIZATION. DESPITE SEVERAL PERIODS OF PRECIP CHANCES...IT DOES NOT APPEAR LIKELY TO BE A WASHOUT. THE BEST INSTABILITY AXIS WILL REMAIN PRIMARILY TO OUR SOUTH AND WEST...THOUGH OCCASIONAL ISOLATED THUNDERSTORMS ARE POSSIBLE IN THE SOUTHWESTERN 1/3 OR 1/4 OF THE CWA. THE POSITION OF THE FRONT WILL DETERMINE WHETHER MOST OR ALL OF THE LAKESHORE RECEIVES PERSISTENT ONSHORE FLOW LATER SUNDAY AND MONDAY...BUT AT LEAST THE IL SHORE WILL LIKELY BE MUCH COOLER THAN INLAND AREAS. AFTER TEMPERATURES LIKELY WELL INTO THE 60S AND EVEN 70S INLAND ON SUNDAY AND MONDAY...TEMPERATURES WILL COOL BACK TO SEASONABLE FOR LATE APRIL TUESDAY...AND EVEN COOLER FOR THE SHORE DUE TO ONSHORE WINDS. RODRIGUEZ/RC && .AVIATION... FOR THE 00Z TAFS... EAST TO NORTHEAST WINDS REMAIN OVER 10 KT OVERNIGHT. RAIN WILL COME TO AN END LATER THIS EVENING AT RFD. WINDS BECOME SOUTHEAST WEDNESDAY AS A LOW PRESSURE SYSTEM MOVES OVER IOWA. SHOWERS ASSOCIATED WITH THE LOW PUSH EAST TUESDAY AFTERNOON REACHING THE EASTERN TERMINALS BY MID AFTN. CIGS WILL LOWER AS THE RAIN APPROACHES AND MAY SEE MVFR CIGS IN THE EVENING. THINKING RFD HAS A BETTER CHANCE OF SEEING MVFR CIGS SINCE IT WILL BE CLOSER TO THE SURFACE LOW. EMBEDDED THUNDER IS POSSIBLE OVER THE EASTERN TERMINALS...BUT THINKING THE BETTER CHANCE IS SOUTH OF THE TERMINALS. KEPT A VCTS GOING DUE TO LOW CONFIDENCE IN TS AT THE TERMINALS. NOT EXPECTING THUNDER TO IMPACT RFD. JEE && .MARINE... 324 PM CDT EAST-NORTHEAST WINDS OVER THE LAKE TODAY WILL TURN SOUTHEAST ON THE SOUTHERN PART OF THE LAKE ON WEDNESDAY AS A FRONTAL BOUNDARY LIFTS NORTH. EXPECT A PERIOD OF SOUTHERLY WINDS ON THURSDAY AS THE FRONT LIFTS FARTHER NORTH. BY THURSDAY NIGHT...A STRONGER COLD FRONT WILL PUSH SOUTH...RESULTING IN A PERIOD OF STRONGER NORTHERLY WINDS INTO FRIDAY. GUSTS WILL LIKELY BE IN THE 25-30 KT RANGE. THE NORTHERLY WINDS AND BUILDING WAVES WILL LIKELY NECESSITATE A SMALL CRAFT ADVISORY FRIDAY INTO FRIDAY EVENING FOR THE ILLINOIS AND INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL BRING FAIRLY LIGHT WINDS FOR THE WHOLE LAKE ON SATURDAY. THEREAFTER...A QUASI-STATIONARY FRONT WILL EXTEND EAST FROM A SURFACE LOW OVER THE PLAINS SUNDAY AND MONDAY...WITH MOST OF THE OPEN WATER AREA LIKELY NORTH OF THE FRONT RESULTING IN MODERATE EASTERLY WINDS. DIRECTIONS COULD BE VARIABLE FOR THE NEARSHORE AND FAR SOUTHERN OPEN WATERS DEPENDING ON THE POSITION OF THE FRONT. THE FRONT WILL SAG WELL SOUTH OF THE LAKE ON TUESDAY...CAUSING NORTHEAST WINDS FOR THE WHOLE LAKE. RC && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM WEDNESDAY. && $$ 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
  [top] Area Forecast Discussion National Weather Service Lincoln IL 828 PM CDT TUE APR 19 2016 .UPDATE... Issued at 827 PM CDT Tue Apr 19 2016 Convection over central Illinois since late afternoon has been most numerous just west of the Illinois River, with scattered thunderstorms and heavier rains at times. Showers have occurred as far east as Springfield, but this has been fading as of late. Overall trend in our forecast area has been for a decreasing trend over the last couple hours, with mainly light rains left from about Peoria-Springfield westward. Latest surface map showing the frontal boundary roughly along the I-72 corridor back into central Missouri where additional thunderstorms are occurring, and a gradual northward shift is expected later tonight. The current HRRR and earlier high- resolution NMM/ARW models have been significantly easing up on the precipitation this evening and are largely dry overnight. Have made some significant adjustments to the PoP trends to back off on the rain chances after midnight as a result. && .SHORT TERM...(Tonight) ISSUED AT 314 PM CDT Tue Apr 19 2016 Large upper level low over the western half of the country is not making much progress, nor is much eastern progression expected in the overnight. With some weak lift over the area and several weak boundaries in the vicinity...some rain chances cannot be ruled out around sunset in the west... as well as increasing slight chances after midnight for much of Central Illinois. At least initially tonight, the rainfall should remain scattered and more showery in nature. The deep low over the western half of the county has much of the northern half of IL and WI in a weak flow pattern as well...winds should remain somewhat light and variable through the overnight hours with some trend to southeasterly. Showers are expected to begin spreading in coverage at least after midnight...but confidence for any one location is small with the slowing system. .LONG TERM...(Wednesday through Tuesday) ISSUED AT 314 PM CDT Tue Apr 19 2016 Shorter range models are generally in agreement with their strength and timing of moving the closed upper low in the High Plains toward the mid-MS Valley by early Thursday. The GFS is a little quicker and a little farther south than the other models but overall their solutions are fairly similar, particularly the NAM and European. Scattered showers and isolated thunderstorms early Wed morning should give way to more widespread coverage of rainfall from later in the morning through the early evening. With deep moisture taking awhile to increase most of the rain accumulation will be on the lighter side. However, the best moisture, but with limited instability, will focus in the warm sector ahead of the cold front Wednesday afternoon into the evening. This will coincide with the highest PoPs and the vast majority of the QPF. Due to the limited instability will stick with isolated thunder through the shorter range. The upper level trough axis from the lifting upper level low is expected to pass through central IL early Thursday and eastern IL Thursday evening. This will bring a gradual end to the showers and isolated thunderstorms from west to east during the day Thursday. A secondary shortwave trough rotating through Great Lakes toward the upper Ohio Valley Friday could keep a few lingering showers south of I-70, otherwise a decreasing cloud trend and temperatures typical for later April in the mid-upper 60s can be expected. A piece of an upper level ridge over the western U.S. will flatten and get pushed east toward our region for early in the weekend. Dry weather with temperatures in the lower 70s can be expected on Saturday as a result. Things get a bit more complicated for Sunday into early next week as a series of vigorous upper level troughs move from the western U.S. toward the Plains and Midwest. In addition, a large upper trough in eastern Canada will move little, resulting in the approaching energy being sheared eastward across the Great Lakes. The resulting upper flow across area would be from the WSW, which means that frontal boundaries could lay out from west to east in the vicinity of Illinois. This would result in an unsettled period of weather with slightly warmer than normal temperatures by early next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 628 PM CDT Tue Apr 19 2016 Outflow boundary about to enter KDEC, and reach KCMI around 0130Z, will briefly switch winds around to the northwest or north before trending back southeast. A warm front just to the north will favor more of an east-southeast wind flow through the night around KPIA and KBMI. More widespread southerly winds on tap on Wednesday as the front lifts further north, and some periods of gusty winds around 15-20 knots are expected toward midday. Rain-wise, fairly widespread shower activity from about KSPI westward at 23Z and also near KUIN-KMQB, where a few thunderstorms are also occurring. Very little movement occurring with the showers and currently do not think the thunder will make it as far as KPIA, but will keep a VCSH mention there. The showers will become less numerous with time this evening, and most of the TAF sites should be dry overnight. However, as the front lifts northward Wednesday morning, more numerous showers will spread into the area from the southwest, and will be most numerous in the afternoon. The arrival of these showers will be accompanied by fairly widespread MVFR ceilings. A few thunderstorms are also possible, and have included a VCTS mention at KDEC/KSPI after 21Z. && .ILX Watches/Warnings/Advisories... NONE. && $$ UPDATE...Geelhart SHORT TERM...HJS LONG TERM...Miller AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1245 PM CDT MON APR 18 2016 ...UPDATED FOR 18Z AVIATION DISCUSSION... .UPDATE... ISSUED AT 645 AM CDT MON APR 18 2016 HAVE UPDATED POP/WX GRIDS THROUGH 00Z LEVERAGING THE RECENT RUNS OF THE HRRR TO BETTER TIME THE ARRIVAL OF THE PRECIP WORKING UP FROM EASTERN KS AND W MO. THIS RESULTED IN DELAYING THE ONSET OF THE HEAVIEST PRECIP BY ONE TO TWO HOURS IN THE SW AND AN OVERALL TIGHTENING OF THE POP GRADIENT ACROSS THE CWA AS THE SYSTEM MOVES THROUGH TODAY. && .SHORT TERM.../TODAY/ ISSUED AT 312 AM CDT MON APR 18 2016 H300 PV ANOMALY WILL LIFT NORTHEASTWARD ALONG THE EASTERN FLANK OF A COLORADO CUTOFF LOW AND INTO IOWA TODAY. THE RESULTANT HEIGHT FALLS WILL DRIVE A 1018 MB SURFACE LOW CURRENTLY OVER OKLAHOMA NORTHWARD ALONG A STATIONARY BOUNDARY INTO WESTERN IOWA BY 18Z TODAY. BROAD KINEMATIC LIFT COMBINED WITH A REGION OF H850 THETA-E ADVECTION WILL BE THE MAIN PRECIPITATION DRIVER TODAY. DEEP MOISTURE AXIS WILL LIKEWISE SHIFT INTO WESTERN IOWA THIS MORNING WITH RELATIVELY NARROW RIBBON OF H700-H500 MIXING RATIO VALUES OVER 4 G/KG OVER CENTRAL IOWA BY 18Z. THE MAIN BAND OF PRECIPITATION THAT WILL IMPACT IOWA HAS ALREADY TAKEN SHAPE IN NE OK AND SE KS AND IS ON TRACK TO REACH THE SW CWA AROUND 12 TO 13Z. IT SHOULD WORK FROM WESTERN TO CENTRAL IOWA BETWEEN 12-18Z AND THEN REACH THE EASTERN CWA CLOSER TO 00Z...ELONGATING AND WEAKENING THROUGH THE DAY. DRY SLOT LOOKS TO IMPINGE ON THE BACKSIDE OF THE RAIN SHIELD THIS AFTERNOON AND HAVE ENDED RAIN CHANCES SOONER IN THE WEST AS A RESULT. HIGHS WILL VARY BETWEEN THE UPPER 70S IN THE EAST WHERE THE RAIN WILL NOT ARRIVE UNTIL LATE IN THE PERIOD TO THE MID 60S WEST. .LONG TERM.../TONIGHT THROUGH SUNDAY/ ISSUED AT 312 AM CDT MON APR 18 2016 LARGE UPPER LEVEL TROUGH IN PLACE ACROSS THE WESTERN US WITH SOUTHERLY FLOW OFF THE GULF INTO THE STATE. THIS SYSTEM WILL SLOWLY MEANDER EASTWARD THROUGH THE WEEK...BRINGING CHANCES OF PRECIPITATION TO THE STATE THROUGH MUCH OF THE WEEK. INITIAL BAND/AREA OF SHOWERS AND ISOLATED THUNDERSTORMS TO LIFT NORTHEASTWARD THROUGH THE CWA TODAY...AND LINGER ACROSS THE CENTRAL/EAST TONIGHT AS AN INVERTED SFC TROUGH FEATURE MOVES THROUGH THE CWA. MAY SEE A FEW ISOLATED STORMS LIFT INTO SC IA TOWARD LATE TONIGHT INTO TUESDAY AS WELL...HOWEVER MAIN PUSH OF MOISTURE AND LIFT TO BE SITUATED TO THE EAST OF THE CWA TUESDAY. GFS/EC MORE BULLISH ACROSS THE EASTERN CWA THAN THE NAM...SO WENT WITH A BLEND AND KEPT SOME LOW POPS ACROSS THE EAST THROUGH THE DAY. OTHERWISE WESTERN CWA TO BE DRY MUCH OF THE DAY TUESDAY INTO TUESDAY EVENING. NEXT SHORTWAVE ENERGY TO LIFT THROUGH THE CWA AS THE MAIN UPPER LOW PUSHES INTO THE CENTRAL PLAINS TOWARD TUESDAY NIGHT INTO WEDNESDAY. THIS WILL BRING ANOTHER ROUND OF PRECIPITATION CHANCES ESPECIALLY LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. DEF ZONE PRECIP TO THEN MOVE THROUGH THURSDAY AS THE MAIN UPPER LOW PUSHES THROUGH THE STATE. KEPT IN A MENTION OF SOME THUNDER...BUT INSTABILITY IS MORE LIMITED SO DO EXPECT MAINLY LIGHT RAIN/SHOWERS. UPPER RIDGING THEN TO BUILD IN FOR FRIDAY INTO SATURDAY...WITH DRY CONDITIONS. WEAK FRONTAL BOUNDARY TO SAG SOUTHWARD ACROSS THE REGION LATE IN THE WEEKEND TO BRING THE NEXT CHANCES FOR SHOWERS AND THUNDERSTORMS. OVERALL TEMPERATURES EXPECTED TO REMAIN WARMER THAN AVERAGE THROUGH THE PERIOD...WITH HIGHS MAINLY IN THE 60S/70S AND LOWS IN THE 40S AND 50S WITH MILDER AIR REMAINING IN PLACE ACROSS THE REGION. && .AVIATION.../FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON/ ISSUED AT 1242 PM CDT MON APR 18 2016 CONFIDENCE HIGH IN THE OCCURRENCE OF RAINFALL IN THE TAF PERIOD. THERE MAY BE BRIEF PERIODS OF IFR VSBYS IN HEAVIER POCKETS OF RAIN...BUT CONFIDENCE NOT HIGH ENOUGH IN TIMING AND LOCATION TO WARRANT FM OR TEMPO GROUP. KEPT MIN CIGS AT 1000FT. THESE MAY NEED TO BE TWEAKED TO IFR IN SUBSEQUENT UPDATES. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SKOW SHORT TERM...SKOW LONG TERM...BEERENDS AVIATION...KOTENBERG
AREA FORECAST DISCUSSION
NWS DES MOINES IA
647 AM CDT MON APR 18 2016 .UPDATE... ISSUED AT 645 AM CDT MON APR 18 2016 HAVE UPDATED POP/WX GRIDS THROUGH 00Z LEVERAGING THE RECENT RUNS OF THE HRRR TO BETTER TIME THE ARRIVAL OF THE PRECIP WORKING UP FROM EASTERN KS AND W MO. THIS RESULTED IN DELAYING THE ONSET OF THE HEAVIEST PRECIP BY ONE TO TWO HOURS IN THE SW AND AN OVERALL TIGHTENING OF THE POP GRADIENT ACROSS THE CWA AS THE SYSTEM MOVES THROUGH TODAY. && .SHORT TERM.../TODAY/ ISSUED AT 312 AM CDT MON APR 18 2016 H300 PV ANOMALY WILL LIFT NORTHEASTWARD ALONG THE EASTERN FLANK OF A COLORADO CUTOFF LOW AND INTO IOWA TODAY. THE RESULTANT HEIGHT FALLS WILL DRIVE A 1018 MB SURFACE LOW CURRENTLY OVER OKLAHOMA NORTHWARD ALONG A STATIONARY BOUNDARY INTO WESTERN IOWA BY 18Z TODAY. BROAD KINEMATIC LIFT COMBINED WITH A REGION OF H850 THETA-E ADVECTION WILL BE THE MAIN PRECIPITATION DRIVER TODAY. DEEP MOISTURE AXIS WILL LIKEWISE SHIFT INTO WESTERN IOWA THIS MORNING WITH RELATIVELY NARROW RIBBON OF H700-H500 MIXING RATIO VALUES OVER 4 G/KG OVER CENTRAL IOWA BY 18Z. THE MAIN BAND OF PRECIPITATION THAT WILL IMPACT IOWA HAS ALREADY TAKEN SHAPE IN NE OK AND SE KS AND IS ON TRACK TO REACH THE SW CWA AROUND 12 TO 13Z. IT SHOULD WORK FROM WESTERN TO CENTRAL IOWA BETWEEN 12-18Z AND THEN REACH THE EASTERN CWA CLOSER TO 00Z...ELONGATING AND WEAKENING THROUGH THE DAY. DRY SLOT LOOKS TO IMPINGE ON THE BACKSIDE OF THE RAIN SHIELD THIS AFTERNOON AND HAVE ENDED RAIN CHANCES SOONER IN THE WEST AS A RESULT. HIGHS WILL VARY BETWEEN THE UPPER 70S IN THE EAST WHERE THE RAIN WILL NOT ARRIVE UNTIL LATE IN THE PERIOD TO THE MID 60S WEST. .LONG TERM.../TONIGHT THROUGH SUNDAY/ ISSUED AT 312 AM CDT MON APR 18 2016 LARGE UPPER LEVEL TROUGH IN PLACE ACROSS THE WESTERN US WITH SOUTHERLY FLOW OFF THE GULF INTO THE STATE. THIS SYSTEM WILL SLOWLY MEANDER EASTWARD THROUGH THE WEEK...BRINGING CHANCES OF PRECIPITATION TO THE STATE THROUGH MUCH OF THE WEEK. INITIAL BAND/AREA OF SHOWERS AND ISOLATED THUNDERSTORMS TO LIFT NORTHEASTWARD THROUGH THE CWA TODAY...AND LINGER ACROSS THE CENTRAL/EAST TONIGHT AS AN INVERTED SFC TROUGH FEATURE MOVES THROUGH THE CWA. MAY SEE A FEW ISOLATED STORMS LIFT INTO SC IA TOWARD LATE TONIGHT INTO TUESDAY AS WELL...HOWEVER MAIN PUSH OF MOISTURE AND LIFT TO BE SITUATED TO THE EAST OF THE CWA TUESDAY. GFS/EC MORE BULLISH ACROSS THE EASTERN CWA THAN THE NAM...SO WENT WITH A BLEND AND KEPT SOME LOW POPS ACROSS THE EAST THROUGH THE DAY. OTHERWISE WESTERN CWA TO BE DRY MUCH OF THE DAY TUESDAY INTO TUESDAY EVENING. NEXT SHORTWAVE ENERGY TO LIFT THROUGH THE CWA AS THE MAIN UPPER LOW PUSHES INTO THE CENTRAL PLAINS TOWARD TUESDAY NIGHT INTO WEDNESDAY. THIS WILL BRING ANOTHER ROUND OF PRECIPITATION CHANCES ESPECIALLY LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. DEF ZONE PRECIP TO THEN MOVE THROUGH THURSDAY AS THE MAIN UPPER LOW PUSHES THROUGH THE STATE. KEPT IN A MENTION OF SOME THUNDER...BUT INSTABILITY IS MORE LIMITED SO DO EXPECT MAINLY LIGHT RAIN/SHOWERS. UPPER RIDGING THEN TO BUILD IN FOR FRIDAY INTO SATURDAY...WITH DRY CONDITIONS. WEAK FRONTAL BOUNDARY TO SAG SOUTHWARD ACROSS THE REGION LATE IN THE WEEKEND TO BRING THE NEXT CHANCES FOR SHOWERS AND THUNDERSTORMS. OVERALL TEMPERATURES EXPECTED TO REMAIN WARMER THAN AVERAGE THROUGH THE PERIOD...WITH HIGHS MAINLY IN THE 60S/70S AND LOWS IN THE 40S AND 50S WITH MILDER AIR REMAINING IN PLACE ACROSS THE REGION. && .AVIATION.../FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING/ ISSUED AT 637 AM CDT MON APR 18 2016 WIDESPREAD MVFR TO POSSIBLY IFR SHOWERS WILL AFFECT THE WESTERN HALF OF IOWA THROUGH 18Z. THIS BAND OF PRECIP WILL PUSH EAST DURING THE AFTERNOON AND AFFECT MOST TAF SITES BETWEEN 17Z AND 03Z. AN EMBEDDED THUNDERSTORM IS ALSO POSSIBLE IN THE AFTERNOON AND EVENING. LOW MVFR TO IFR STRATUS WILL LINGER IN THE WAKE OF THE DEPARTING SYSTEM OVERNIGHT TONIGHT. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...SKOW SHORT TERM...SKOW LONG TERM...BEERENDS AVIATION...SKOW
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
309 PM CDT MON APR 18 2016 .SHORT TERM...(This Evening through Tuesday) Issued at 309 PM CDT MON APR 18 2016 A shortwave continues to lift through northeast KS per the 20Z water vapor imagery. Meanwhile the cut off upper low remains over northwest CO. Surface obs indicate the trough axis is just to the east of the forecast area with some drier and cooler air advecting in from the northwest. Subsidence from the shortwave is expected to keep the weather dry over the forecast area for tonight. The main concern is whether some fog develops. This is highly dependent on whether skies clear out and the boundary layer radiates outs. Latest visible satellite continues to show expansive stratocu deck across western KS and the 18Z RAP has trended towards keeping a stratus deck over the forecast area through the night. Since the HRRR/RAP/SREF show visibilities remaining at 5 miles or better, will keep the mention of patchy fog across north central KS inserted by the prev shift since some breaks in the clouds are possible, but will not expand it and any further. Later shifts will need to watch the cloud trends for clearing. Then the potential for fog ,even dense fog, would increase. Have not made many changes to the low temp forecast as models continue to support readings from the mid 40s across north central KS to the lower 50s in east central KS as a result of some weak cold air advection. For Tuesday, models show the potential for another shortwave to round the bottom of the cut off low and lift north. As it does, there is some modest moisture return as 850 winds veer around more to the southeast. So with the prospects for increasing large scale forcing, chances for precip increase through the afternoon from south to north. Models show very modest instability developing given mid level lapse rates remaining around 6 C/km. The GFS is most aggressive in developing some instability across east central KS tomorrow afternoon, but it also tries to break out the sun and heat things up a little more. So while some thunderstorms cannot be ruled out, think rain showers are most likely. Models do not show any warm air advection and feel like clouds are going to be hard to scour out. With this in mind, have afternoon highs in the mid and upper 60s. .LONG TERM...(Tuesday Night through Monday) Issued at 309 PM CDT MON APR 18 2016 Models are trending to a stronger wave rotating around the upper low Tuesday night into Wednesday, with good forcing aloft interacting with increasing moisture for another likely moderate, fairly widespread rain event. It again appears to occur in the late Tuesday night to Wednesday morning hours but a lack of consistent training and instability still weak at best should keep amounts from being troublesome. May have some clearing in the afternoon for temps to push into the middle to upper 60s but this could be a challenge depending on precip and temp timing. Not expecting much chance for fog development WEdnesday night with northwest winds increasing behind a weak surface trough and some high cloud remaining. The northwest winds will not be able to bring in much air in this stagnant pattern and warmer temps are anticipated for Thursday. Will need to maintain some small pops for most areas through early Thursday with the mean upper trough still upstream. Longer range periods continue to show upper ridging in control of the central CONUS into at least Saturday, but models become increasingly into disagreement in handling of energy along nearly the Pacific coast of much of North America. The 12Z ECMWF weakens much of this energy, allowing for at least weak ridging aloft to persist, allowing a front to sink south through the Northern Plains, while the 12Z GFS and a few of its ensembles brings a shortwave on east through the Southern Rockies over the weekend with a more obviously wet and stormy scenario for late Sunday into Monday. With many other GFS ensembles differing significantly, have kept precip chances somewhat reduced compared to the GFS. Highs still look to rise toward 80 for the weekend. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon) Issued at 1225 PM CDT MON APR 18 2016 Don`t have much confidence in the CIGS forecast this afternoon. Models continue to show CIGS scattering out but satellite and obs show CIGS around 1 KFT still holding in strong across southwestern KS. Because of this have held onto the IFR and MVFR CIGS longer into the forecast period. There remains a potential for fog overnight, however with the low confidence in the CIGS forecast I`m not sure if there will be enough cooling for fog formation. Later shifts will need to monitor this through the evening. && .TOP Watches/Warnings/Advisories... NONE. && $$ SHORT TERM...Wolters LONG TERM...65 AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
542 PM CDT MON APR 18 2016 .DISCUSSION... 00Z TAF ISSUANCE. && .AVIATION... COMPLEX OF SHRA/TSRA OVER W LA FROM POE TO LCH AND CAMERON EXTENDING OFFSHORE...MOVING EAST AT ~10 MPH. THUS...PREVAILING SHRA/TSRA AND MVFR CEILINGS EXPECTED AT LCH...AND AT AEX SHORTLY AS IT ARRIVES. FOR BPT...HEAVIEST CONVECTION OUT OF SE TX...WITH ONLY INTERMITTENT SHRA EXPECTED THIS EVENING AND OVERNIGHT...BUT MVFR TO IFR CEILINGS EXPECTED. AT LFT/ARA...LEFT TEMPO GROUP FOR INTERMITTENT SHRA AS THIS COMPLEX MOVES FURTHER EAST...BUT BELIEVE IT WILL CONTINUE WEAKENING AND BE CLOSE TO DISSIPATION BY THE TIME IT ARRIVES OVER ACADIANA. OTHERWISE...MVFR TO IFR CEILINGS EXPECTED AT REMAINING SITES OVERNIGHT INTO TUE MORNING. FOR LATE TUE MORNING INTO THE AFTERNOON...ANOTHER ROUND OF SHRA/TSRA EXPECTED TO FORM OVER SE TX/W LA BY LATE MORNING INTO THE AFTERNOON HOURS AND SPREAD EAST AS WELL. PLACED PROB30 GROUP FROM 18-24Z FOR TSRA & IFR VSBY/CEILINGS. && .PREV DISCUSSION... /ISSUED 453 PM CDT MON APR 18 2016/ DISCUSSION... IN TERMS OF THE OVERALL PATTERN EVOLUTION...LITTLE HAS CHANGED SINCE YESTERDAY...WITH AN UPPER LOW/TROF OVER THE ROCKIES FCST TO SLOWLY TRANSLATE EWD AS THE DOWNSTREAM RIDGE OVER THE ERN CONUS BREAKS DOWN...EVENTUALLY SENDING A CDFNT THROUGH THE REGION LATE THU INTO FRIDAY. UNTIL THEN...A SOUTHERLY MOIST LOW LEVEL INFLOW ALONG WITH PERIODIC IMPULSES EJECTING DOWNSTREAM OF THE UPPER LOW WILL AID IN GENERATING CLUSTERS OF SHOWERS AND THUNDERSTORMS. FOR THE REST OF TODAY AND INTO TONIGHT...CURRENT N-S ORIENTED COMPLEX OF CONVECTION IS PROGGED TO CONTINUE SLOWLY EWD...WITH THE MODEL GUIDANCE THAT ACTUALLY DEPICTS IT INDICATING WEAKENING AND DISSIPATION AS IT REACHES INTO EAST/SOUTH CENTRAL LOUISIANA. THE EXPERIMENTAL HRRR APPEARS TO HAVE CAPTURED THIS CONVECTION THE BEST...AND IS IN LINE WITH THIS SCENARIO. IT SHOWS A GENERAL 1 TO 2 INCH SWATH OF RAIN GENERALLY WITHIN A REGION BOUNDED BY THE CURRENT WESTERN EDGE OF THE CONVECTION TO ROUGHLY AN ALEXANDRIA TO LAKE ARTHUR LINE...WITH AMOUNTS TAPERING OF QUICKLY TO AROUND A TENTH OF AN INCH OR LESS EAST OF A MARKSVILLE TO LAFAYETTE LINE. VERY LITTLE ADDITIONAL RAINFALL IS FORECAST OVER EAST TEXAS THE REST OF THE AFTERNOON AND EVENING...THOUGH INDICATIONS IN THIS AND OTHER GUIDANCE POINT TO NEW CONVECTIVE DEVELOPMENT OVER EAST TX AND WESTERN LA DURING THE OVERNIGHT HRS TWD TUE MORNING. MSTR CONTENT IS PROGGED TO REMAIN QUITE HIGH...MEANING ANY CONVECTION THAT DEVELOPS WILL BE CAPABLE OF HIGH RAINFALL RATES...AND WILL ALSO BE FALLING OVER AREAS THAT RECEIVED ANYWHERE FROM 2 TO UPWARDS OF 6 INCHES OF RAIN TODAY. THUS...EVEN THOUGH NOT MUCH RAIN IS EXPECTED IN THE WATCH AREA FOR A PERIOD OF TIME AFTER THE CURRENT ACTIVITY MOVES OFF TO THE EAST...OPTED TO LEAVE THE FLOOD WATCH IN PLACE THROUGH THE CURRENT 7AM TUE EXPIRATION TIME. PENDING THE DEVELOPMENT OF THIS ADDITIONAL RAINFALL...THE WATCH WILL EITHER BE CANCELLED OR EXTENDED IN TIME LATER SHIFTS. FCST BEYOND THIS TIME BECOMES MORE UNCERTAIN...BUT IT APPEARS THAT ANOTHER ROUND OF RAIN WILL MOVE THROUGH THE AREA ON WED AS ONE OF THE AFOREMENTIONED IMPULSES TRAVERSES THE REGION...WITH YET MORE RAIN ON THURSDAY AS THE CDFNT SAGS INTO THE GULF COAST STATES. SOME LINGERING RAIN IS POSSIBLE ON FRIDAY...BUT AT LEAST THE START OF THE WEEKEND LOOKS DRY WITH RIDGING BUILDING IN BEHIND THE DEPARTING TROF. 13 MARINE... LOW PRESSURE TO THE NORTHWEST AND HIGH PRESSURE TO THE EAST WILL KEEP THE NORTHWEST GULF OF MEXICO IN A LONG FETCH OF ONSHORE WINDS. ELEVATED WINDS WILL CONTINUE THIS EVENING...BUT BEGIN TO SUBSIDE DURING THE OVERNIGHT PERIOD. ADDITIONALLY...SHOWER AND THUNDERSTORM ACTIVITY WILL CONTINUE TO BE POSSIBLE AS DEEPENING MOISTURE COMBINES WITH AN AREA OF LOW PRESSURE ALOFT OVER THE SOUTHERN ROCKIES AND HIGH PLAINS. 13 && .PRELIMINARY POINT TEMPS/POPS... AEX 63 76 64 79 / 60 70 50 50 LCH 69 77 68 79 / 80 70 40 50 LFT 67 78 67 80 / 40 40 30 40 BPT 68 77 68 79 / 70 90 40 50 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR LAZ027-030-041-073. COASTAL FLOOD ADVISORY UNTIL 7 AM CDT TUESDAY FOR LAZ041-052>054- 073-074. TX...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR TXZ180-201-215-216- 259>262. COASTAL FLOOD ADVISORY UNTIL 7 AM CDT TUESDAY FOR TXZ215-216. GM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY FOR GMZ470-472-475. SMALL CRAFT EXERCISE CAUTION THROUGH TUESDAY MORNING FOR GMZ450- 452-455. && $$ AVIATION...08
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
453 PM CDT MON APR 18 2016 .DISCUSSION... IN TERMS OF THE OVERALL PATTERN EVOLUTION...LITTLE HAS CHANGED SINCE YESTERDAY...WITH AN UPPER LOW/TROF OVER THE ROCKIES FCST TO SLOWLY TRANSLATE EWD AS THE DOWNSTREAM RIDGE OVER THE ERN CONUS BREAKS DOWN...EVENTUALLY SENDING A CDFNT THROUGH THE REGION LATE THU INTO FRIDAY. UNTIL THEN...A SOUTHERLY MOIST LOW LEVEL INFLOW ALONG WITH PERIODIC IMPULSES EJECTING DOWNSTREAM OF THE UPPER LOW WILL AID IN GENERATING CLUSTERS OF SHOWERS AND THUNDERSTORMS. FOR THE REST OF TODAY AND INTO TONIGHT...CURRENT N-S ORIENTED COMPLEX OF CONVECTION IS PROGGED TO CONTINUE SLOWLY EWD...WITH THE MODEL GUIDANCE THAT ACTUALLY DEPICTS IT INDICATING WEAKENING AND DISSIPATION AS IT REACHES INTO EAST/SOUTH CENTRAL LOUISIANA. THE EXPERIMENTAL HRRR APPEARS TO HAVE CAPTURED THIS CONVECTION THE BEST...AND IS IN LINE WITH THIS SCENARIO. IT SHOWS A GENERAL 1 TO 2 INCH SWATH OF RAIN GENERALLY WITHIN A REGION BOUNDED BY THE CURRENT WESTERN EDGE OF THE CONVECTION TO ROUGHLY AN ALEXANDRIA TO LAKE ARTHUR LINE...WITH AMOUNTS TAPERING OF QUICKLY TO AROUND A TENTH OF AN INCH OR LESS EAST OF A MARKSVILLE TO LAFAYETTE LINE. VERY LITTLE ADDITIONAL RAINFALL IS FORECAST OVER EAST TEXAS THE REST OF THE AFTERNOON AND EVENING...THOUGH INDICATIONS IN THIS AND OTHER GUIDANCE POINT TO NEW CONVECTIVE DEVELOPMENT OVER EAST TX AND WESTERN LA DURING THE OVERNIGHT HRS TWD TUE MORNING. MSTR CONTENT IS PROGGED TO REMAIN QUITE HIGH...MEANING ANY CONVECTION THAT DEVELOPS WILL BE CAPABLE OF HIGH RAINFALL RATES...AND WILL ALSO BE FALLING OVER AREAS THAT RECEIVED ANYWHERE FROM 2 TO UPWARDS OF 6 INCHES OF RAIN TODAY. THUS...EVEN THOUGH NOT MUCH RAIN IS EXPECTED IN THE WATCH AREA FOR A PERIOD OF TIME AFTER THE CURRENT ACTIVITY MOVES OFF TO THE EAST...OPTED TO LEAVE THE FLOOD WATCH IN PLACE THROUGH THE CURRENT 7AM TUE EXPIRATION TIME. PENDING THE DEVELOPMENT OF THIS ADDITIONAL RAINFALL...THE WATCH WILL EITHER BE CANCELLED OR EXTENDED IN TIME LATER SHIFTS. FCST BEYOND THIS TIME BECOMES MORE UNCERTAIN...BUT IT APPEARS THAT ANOTHER ROUND OF RAIN WILL MOVE THROUGH THE AREA ON WED AS ONE OF THE AFOREMENTIONED IMPULSES TRAVERSES THE REGION...WITH YET MORE RAIN ON THURSDAY AS THE CDFNT SAGS INTO THE GULF COAST STATES. SOME LINGERING RAIN IS POSSIBLE ON FRIDAY...BUT AT LEAST THE START OF THE WEEKEND LOOKS DRY WITH RIDGING BUILDING IN BEHIND THE DEPARTING TROF. 13 && .MARINE... LOW PRESSURE TO THE NORTHWEST AND HIGH PRESSURE TO THE EAST WILL KEEP THE NORTHWEST GULF OF MEXICO IN A LONG FETCH OF ONSHORE WINDS. ELEVATED WINDS WILL CONTINUE THIS EVENING...BUT BEGIN TO SUBSIDE DURING THE OVERNIGHT PERIOD. ADDITIONALLY...SHOWER AND THUNDERSTORM ACTIVITY WILL CONTINUE TO BE POSSIBLE AS DEEPENING MOISTURE COMBINES WITH AN AREA OF LOW PRESSURE ALOFT OVER THE SOUTHERN ROCKIES AND HIGH PLAINS. 13 && .PRELIMINARY POINT TEMPS/POPS... AEX 63 76 64 79 / 60 70 50 50 LCH 69 77 68 79 / 80 70 40 50 LFT 67 78 67 80 / 40 40 30 40 BPT 68 77 68 79 / 70 90 40 50 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR LAZ027-030-041-073. COASTAL FLOOD ADVISORY UNTIL 7 AM CDT TUESDAY FOR LAZ041-052>054- 073-074. TX...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR TXZ180-201-215-216- 259>262. COASTAL FLOOD ADVISORY UNTIL 7 AM CDT TUESDAY FOR TXZ215-216. GM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY FOR GMZ470-472-475. SMALL CRAFT EXERCISE CAUTION THROUGH TUESDAY MORNING FOR GMZ450- 452-455. && $$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
128 PM CDT MON APR 18 2016 .AVIATION... FOR THE 18/18Z TAFS...AXIS OF MODERATE TO OCCASIONALLY HEAYY RAIN CONTINUES TO DRIFT SLOWLY EWD ACROSS EXTREME ERN TX INTO SW AR AND WRN LA. BACK EDGE OF THE RAIN HAS EXITED TYR/GGG AND WILL SOON AT LFK WHILE ELD/MLU REMAIN JUST OUTSIDE OF THE ERN EDGE OF THE RAIN. CIGS WILL BE VARYING BETWEEN IFR AND MVFR FOR MUCH OF THE TAF PD WITH SOME OCCCASIONAL PERIODS OF LOW VFR CIGS POSSIBLE LATER THIS AFTERNOON WHEN BREAKS IN THE RAIN OCCUR. DO EXPECT A LULL IN RAIN OVERNIGHT BUT ADDITIONAL CONVECTION IS EXPECTED ON TUESDAY AS NEW IMPULSES OF UPPER LEVEL ENERGY MOVE IN FROM THE WEST. WINDS WILL MAINTAIN E/SE COMPONENTS WITH SPEEDS GENERALLY AT 10 KTS OR LESS. /19/ && .PREV DISCUSSION... /ISSUED 1201 PM CDT MON APR 18 2016/ DISCUSSION... A N-S BAND OF SHRA...WITH A FEW EMBEDDED TSRA...REMAINS PERSISTENT LATE THIS MORNING ACROSS EXTREME SE OK/ADJACENT SW AR/EXTREME ERN TX/WRN LA...ALTHOUGH RADAR TRENDS HAVE SHOWN THE SHRA SLOWLY BEGIN TO DIMINISH ACROSS THE WRN SECTIONS OF E TX. THIS APPEARS TO BE IN CONJUNCTION WITH MID LEVEL DRY AIR BEGINNING TO SLOWLY ENTRAIN EWD ALONG AN ATTENDENT SHORTWAVE THAT IS LIFTING NE AHEAD OF THE NEARLY STATIONARY CLOSED LOW SPINNING OVER THE ROCKIES. THE LATEST RUNS OF THE HRRR HAVE SHOWN THE ONGOING CONVECTION SLOWLY DIMINISHING FROM W TO E THIS AFTERNOON...AS HAS THE 12Z GFS...ALTHOUGH THE 12Z NAM IS MUCH SLOWER TO DO SO AND MAINTAINS THE CONVECTION OVER AREAS WHERE IT IS CURRENTLY RAINING. GIVEN THE SLOWING TRENDS WITH THE LEAD GUST FRONT ALONG THE ONGOING MCS OVER EXTREME SE TX/WRN GULF...CONFIDENCE HAS INCREASED THAT THE CONVECTION WILL NOT BE IN ANY HURRY TO KICK EWD...THUS HAVE INCREASED POPS TO HIGH END CATEGORICAL/HIGH LIKELIES OVER EXTREME ERN TX/WRN LA/SW AR WITH THE ANTICIPATION THAT THE CONVECTION WILL ONLY SHUNT A BIT FARTHER EWD THIS AFTERNOON. DID RAISE POPS TO HIGH CHANCE ALONG THE LAST N-S TIER OF NCNTRL LA PARISHES AS THE CONVECTION REACHES THESE AREAS BY MID TO LATE AFTERNOON. FARTHER W WHERE THE SHRA HAVE DIMINISHED OVER THE WRN SECTIONS OF E TX...HAVE LOWERED POPS BACK TO HIGH CHANCE WITH ANY ADDITIONAL RAINFALL AMOUNTS ONLY EXPECTED TO BE LIGHT. SFC/MLCAPES REMAIN NON-EXISTENT THIS MORNING ACROSS THE REGION...AND WHILE THIS MAY CHANGE SLIGHTLY AS AN INVERTED SFC TROUGH OVER SE TX EXTENDED NE INTO NCNTRL LA LIFTS SLOWLY NWD THIS AFTERNOON...HAVE OPTED TO REDUCE THUNDER MENTION TO ISOLATED IN THE FORECAST GIVEN THE VERY SATURATED/NEARLY MOIST ADIABATIC COLUMN IN PLACE. DID EXPAND HEAVY RAINFALL MENTION ANOTHER COLUMN OF COUNTIES/PARISHES E PER THE RECENT RADAR TRENDS...BUT THESE AREAS HAVE SEEN LITTLE RAINFALL THUS FAR DURING THIS EVENT AND SHOULD BE ABLE TO HANDLE THIS RAINFALL. THUS...HAVE NOT MADE ANY CHANGES TO THE CURRENT FFA ATTM. HAVE ALSO LOWERED MAX TEMPS ACROSS THE RAIN-COOLED AREAS...AS THEY MAY BE HARD PRESSED TO REACH 70 DEGREES THIS AFTERNOON. ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY. 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 69 63 75 64 / 100 80 80 50 MLU 77 60 75 63 / 50 40 60 50 DEQ 69 62 71 61 / 100 80 80 60 TXK 69 63 73 62 / 100 80 80 60 ELD 74 60 74 63 / 70 70 80 60 TYR 72 65 74 64 / 50 80 80 50 GGG 70 64 74 63 / 60 80 80 50 LFK 71 66 75 65 / 100 80 70 40 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR ARZ050-051-059-060- 070-071. LA...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR LAZ001-002-010-017. OK...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR OKZ077. TX...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR TXZ096-097-108>112- 124>126-136>138-149>153-165>167. && $$ 19/15
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1201 PM CDT MON APR 18 2016 .DISCUSSION... A N-S BAND OF SHRA...WITH A FEW EMBEDDED TSRA...REMAINS PERSISTENT LATE THIS MORNING ACROSS EXTREME SE OK/ADJACENT SW AR/EXTREME ERN TX/WRN LA...ALTHOUGH RADAR TRENDS HAVE SHOWN THE SHRA SLOWLY BEGIN TO DIMINISH ACROSS THE WRN SECTIONS OF E TX. THIS APPEARS TO BE IN CONJUNCTION WITH MID LEVEL DRY AIR BEGINNING TO SLOWLY ENTRAIN EWD ALONG AN ATTENDENT SHORTWAVE THAT IS LIFTING NE AHEAD OF THE NEARLY STATIONARY CLOSED LOW SPINNING OVER THE ROCKIES. THE LATEST RUNS OF THE HRRR HAVE SHOWN THE ONGOING CONVECTION SLOWLY DIMINISHING FROM W TO E THIS AFTERNOON...AS HAS THE 12Z GFS...ALTHOUGH THE 12Z NAM IS MUCH SLOWER TO DO SO AND MAINTAINS THE CONVECTION OVER AREAS WHERE IT IS CURRENTLY RAINING. GIVEN THE SLOWING TRENDS WITH THE LEAD GUST FRONT ALONG THE ONGOING MCS OVER EXTREME SE TX/WRN GULF...CONFIDENCE HAS INCREASED THAT THE CONVECTION WILL NOT BE IN ANY HURRY TO KICK EWD...THUS HAVE INCREASED POPS TO HIGH END CATEGORICAL/HIGH LIKELIES OVER EXTREME ERN TX/WRN LA/SW AR WITH THE ANTICIPATION THAT THE CONVECTION WILL ONLY SHUNT A BIT FARTHER EWD THIS AFTERNOON. DID RAISE POPS TO HIGH CHANCE ALONG THE LAST N-S TIER OF NCNTRL LA PARISHES AS THE CONVECTION REACHES THESE AREAS BY MID TO LATE AFTERNOON. FARTHER W WHERE THE SHRA HAVE DIMINISHED OVER THE WRN SECTIONS OF E TX...HAVE LOWERED POPS BACK TO HIGH CHANCE WITH ANY ADDITIONAL RAINFALL AMOUNTS ONLY EXPECTED TO BE LIGHT. SFC/MLCAPES REMAIN NON-EXISTENT THIS MORNING ACROSS THE REGION...AND WHILE THIS MAY CHANGE SLIGHTLY AS AN INVERTED SFC TROUGH OVER SE TX EXTENDED NE INTO NCNTRL LA LIFTS SLOWLY NWD THIS AFTERNOON...HAVE OPTED TO REDUCE THUNDER MENTION TO ISOLATED IN THE FORECAST GIVEN THE VERY SATURATED/NEARLY MOIST ADIABATIC COLUMN IN PLACE. DID EXPAND HEAVY RAINFALL MENTION ANOTHER COLUMN OF COUNTIES/PARISHES E PER THE RECENT RADAR TRENDS...BUT THESE AREAS HAVE SEEN LITTLE RAINFALL THUS FAR DURING THIS EVENT AND SHOULD BE ABLE TO HANDLE THIS RAINFALL. THUS...HAVE NOT MADE ANY CHANGES TO THE CURRENT FFA ATTM. HAVE ALSO LOWERED MAX TEMPS ACROSS THE RAIN-COOLED AREAS...AS THEY MAY BE HARD PRESSED TO REACH 70 DEGREES THIS AFTERNOON. ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY. 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 69 63 75 64 / 100 80 80 50 MLU 77 60 75 63 / 50 40 60 50 DEQ 69 62 71 61 / 100 80 80 60 TXK 69 63 73 62 / 100 80 80 60 ELD 74 60 74 63 / 70 70 80 60 TYR 72 65 74 64 / 50 80 80 50 GGG 70 64 74 63 / 60 80 80 50 LFK 71 66 75 65 / 100 80 70 40 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR ARZ050-051-059-060- 070-071. LA...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR LAZ001-002-010-017. OK...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR OKZ077. TX...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR TXZ096-097-108>112- 124>126-136>138-149>153-165>167. && $$ 15
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1258 PM EDT MON APR 18 2016 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 457 AM EDT MON APR 18 2016 WV IMAGERY AND RAP ANALYSIS INDICATED A PERSISTENT BLOCKING PATTERN ACROSS THE CONUS WITH VEERING WNW MID/UPPER LEVEL FLOW THROUGH NRN ONTARIO IN RESPONSE TO A RIDGE BUILDING INTO SRN ALBERTA/SASK. AT THE SFC...A COLD FRONT HAD MOVED THROUGH LAKE SUPERIOR AND WAS SLOWLY SINKING THROUGH NRN UPPER MI. LIGHT PCPN ASSOCIATED WITH 850- 600 MB FGEN AND DEEPER SATURATION WAS MAINLY NORTH OF LAKE SUPERIOR. HOWEVER...SCT/ISOLD LIGHT SHOWERS OR SPRINKLES HAVE ALSO DEVELOPED OVER LAKE SUPERIOR TO NEAR THE KEWEENAW. TODAY... MODELS SUGGEST THAT THE FRONT WILL MOVE THROUGH MOST OF UPPER MI BY 18Z AND THROUGH THE FAR SOUTH BY 21Z WITH A CONTINUED TREND TOWARD A SLOWER ARRIVAL OF PCPN ASSOCIATED WITH THE FGEN LAGGING WELL TO THE NORTH OF THE FRONT. THERE MAY BE A FEW SPRINKLES THIS MORNING BUT THE BEST CHANCE FOR MEASURABLE RAIN WILL BE MAINLY OVER THE KEWEENAW THIS MORNING AND THE REST OF NORTHERN UPPER MI THIS AFTERNOON. WITH THE WEAK DISORGANIZED FORCING AS THE STRONGER FGEN SLIDES OFF TO THE EAST OF LAKE SUPERIOR AND LIMITED MOISTURE INFLOW...ONLY CHANCE POPS WERE MENTIONED. ANY RAINFALL AMOUNTS WILL BE LIGHT...A TENTH OF AN INCH OR LESS. NRLY WINDS WILL KEEP HIGHS IN THE 40S OVER THE NORTH BUT WITH THE SLOWER FRONT...TEMPS TO AROUND 70 ARE EXPECTED AGAIN OVER THE SOUTH. TONIGHT...SOME LOW END POPS ASSOCIATED WITH THE FRONT WILL LINGER THIS EVENING...MAINLY OVER THE SOUTH. EXPECT THAT RAIN ASSOCIATED WITH A TROUGH AND BAND OF MOISTURE MOVING THROUGH THE UPPER MS VALLEY WILL REMAIN TO THE SW OF THE CWA...ESPECIALLY GIVEN DRY ERLY LOW LEVEL FLOW ASSOCIATED WITH THE RIDGE BUILDING INTO THE NRN LAKES. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 333 AM EDT MON APR 18 2016 MAY SEE SOME LIGHT RAIN SHOWERS BRUSHING FAR WRN UPPER MI TUE INTO TUE NIGHT DUE TO WAA/ISENTROPIC ASCENT BETWEEN A SFC HIGH E OF THE CWA AND PLAINS LOW PRESSURE. UPPER RIDGING OVER THE CWA AND ON THE E SIDE OF AN UPPER LOW OVER THE WRN PLAINS WILL KEEP MOST OF THE AREA DRY TUE AND TUE NIGHT. AN UPPER LOW MOVING THROUGH NRN CANADA WILL CAUSE A SHORTWAVE TO MOVE INTO THE NRN U.S. AND SHEAR THE PLAINS UPPER LOW INTO A TROUGH THAT SHIFTS ACROSS THE CWA WED NIGHT/THU. THIS WILL BRING LIGHT RAIN CHANCES TO THE ENTIRE AREA WED INTO THU. FRI LOOKS DRY FOR THE MOST PART (NEWEST GFS RUN NOW COMING IN WITH SOME RAIN/SNOW OVER THE W LATE...BUT ALL OTHER MODELS ARE DRY) AS SFC HIGH PRESSURE MOVES IN. CERTAINLY WILL BE COOLER AS 850MB TEMPS DROP NEAR OR BELOW 0C BEHIND THE UPPER TROUGH THAT MOVED THROUGH THU. HAVE HIGHS ON FRI IN THE MID 40S NEAR LAKE SUPERIOR TO THE MID 50S ALONG THE WI BORDER. LOW CONFIDENCE GOING INTO THE WEEKEND AS THE 00Z/18 GFS SHOWS WAA RAIN/SNOW LATE FRI INTO SAT WHILE THE 12Z/17 ECMWF IS DRY. MODELS ALL KEEP 850MB TEMPS AOB 0C THROUGH THE WEEKEND. WILL RUN WITH A BLEND OF MODELS GIVEN THE UNCERTAINTY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1257 PM EDT MON APR 18 2016 AS COOLER AND MOISTER AIR ARRIVES INTO THE AFTERNOON...EXPECT MVFR CONDITIONS TO DEVELOP UNDER A SHARPENING LOW LEVEL INVERSION. SOME MVFR CIGS ARE POSSIBLE AT SAW AND PUT THEM IN FOR LATE THIS AFTERNOON...WHERE THE LOW LEVEL NE FLOW WILL HAVE A GREATER UPSLOPE COMPONENT. KCMX WILL HAVE MOSTLY MVFR CONDITIONS THIS AFTERNOON WITH THE LIGHT RAIN SHOWERS. THE ARRIVAL OF DRIER AIR AFT 19/00Z WILL RESULT IN LIFTING CIGS AT CMX AND THIS EVENING AT AT SAW. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 457 AM EDT MON APR 18 2016 EXPECT NE WINDS OF 15 TO 25 KNOTS TO GRADUALLY WEAKEN THIS AFTERNOON BEFORE HIGH PRESSURE BRINGS LIGHT WINDS THROUGH WEDNESDAY. A TROUGH WILL TRACK SOUTHEASTWARD ACROSS LAKE SUPERIOR ON THURSDAY...BRINGING A QUICK ROUND OF N WINDS OF 20 TO 25 KNOTS. EXPECT N WINDS TO CONTINUE THROUGH FRIDAY AS HIGH PRESSURE SETTLES TO THE NW. && .HYDROLOGY... ISSUED AT 333 AM EDT MON APR 18 2016 CONTINUING TO MONITOR A COUPLE OF RIVERS NEARING ACTION (BANKFULL) STAGE...THE LOWER PORTION OF THE STURGEON RIVER (BARAGA/HOUGHTON COUNTY) AND THE TRAP ROCK RIVER. EVEN IF THESE RIVERS EXCEED ACTION STAGE...THEY ARE NOT ANTICIPATED TO EXCEED MINOR FLOOD STAGE. OVERALL VERY MINOR IMPACTS FOR SPRING SNOWMELT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLB HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
741 AM EDT MON APR 18 2016 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 457 AM EDT MON APR 18 2016 WV IMAGERY AND RAP ANALYSIS INDICATED A PERSISTENT BLOCKING PATTERN ACROSS THE CONUS WITH VEERING WNW MID/UPPER LEVEL FLOW THROUGH NRN ONTARIO IN RESPONSE TO A RIDGE BUILDING INTO SRN ALBERTA/SASK. AT THE SFC...A COLD FRONT HAD MOVED THROUGH LAKE SUPERIOR AND WAS SLOWLY SINKING THROUGH NRN UPPER MI. LIGHT PCPN ASSOCIATED WITH 850- 600 MB FGEN AND DEEPER SATURATION WAS MAINLY NORTH OF LAKE SUPERIOR. HOWEVER...SCT/ISOLD LIGHT SHOWERS OR SPRINKLES HAVE ALSO DEVELOPED OVER LAKE SUPERIOR TO NEAR THE KEWEENAW. TODAY... MODELS SUGGEST THAT THE FRONT WILL MOVE THROUGH MOST OF UPPER MI BY 18Z AND THROUGH THE FAR SOUTH BY 21Z WITH A CONTINUED TREND TOWARD A SLOWER ARRIVAL OF PCPN ASSOCIATED WITH THE FGEN LAGGING WELL TO THE NORTH OF THE FRONT. THERE MAY BE A FEW SPRINKLES THIS MORNING BUT THE BEST CHANCE FOR MEASURABLE RAIN WILL BE MAINLY OVER THE KEWEENAW THIS MORNING AND THE REST OF NORTHERN UPPER MI THIS AFTERNOON. WITH THE WEAK DISORGANIZED FORCING AS THE STRONGER FGEN SLIDES OFF TO THE EAST OF LAKE SUPERIOR AND LIMITED MOISTURE INFLOW...ONLY CHANCE POPS WERE MENTIONED. ANY RAINFALL AMOUNTS WILL BE LIGHT...A TENTH OF AN INCH OR LESS. NRLY WINDS WILL KEEP HIGHS IN THE 40S OVER THE NORTH BUT WITH THE SLOWER FRONT...TEMPS TO AROUND 70 ARE EXPECTED AGAIN OVER THE SOUTH. TONIGHT...SOME LOW END POPS ASSOCIATED WITH THE FRONT WILL LINGER THIS EVENING...MAINLY OVER THE SOUTH. EXPECT THAT RAIN ASSOCIATED WITH A TROUGH AND BAND OF MOISTURE MOVING THROUGH THE UPPER MS VALLEY WILL REMAIN TO THE SW OF THE CWA...ESPECIALLY GIVEN DRY ERLY LOW LEVEL FLOW ASSOCIATED WITH THE RIDGE BUILDING INTO THE NRN LAKES. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 333 AM EDT MON APR 18 2016 MAY SEE SOME LIGHT RAIN SHOWERS BRUSHING FAR WRN UPPER MI TUE INTO TUE NIGHT DUE TO WAA/ISENTROPIC ASCENT BETWEEN A SFC HIGH E OF THE CWA AND PLAINS LOW PRESSURE. UPPER RIDGING OVER THE CWA AND ON THE E SIDE OF AN UPPER LOW OVER THE WRN PLAINS WILL KEEP MOST OF THE AREA DRY TUE AND TUE NIGHT. AN UPPER LOW MOVING THROUGH NRN CANADA WILL CAUSE A SHORTWAVE TO MOVE INTO THE NRN U.S. AND SHEAR THE PLAINS UPPER LOW INTO A TROUGH THAT SHIFTS ACROSS THE CWA WED NIGHT/THU. THIS WILL BRING LIGHT RAIN CHANCES TO THE ENTIRE AREA WED INTO THU. FRI LOOKS DRY FOR THE MOST PART (NEWEST GFS RUN NOW COMING IN WITH SOME RAIN/SNOW OVER THE W LATE...BUT ALL OTHER MODELS ARE DRY) AS SFC HIGH PRESSURE MOVES IN. CERTAINLY WILL BE COOLER AS 850MB TEMPS DROP NEAR OR BELOW 0C BEHIND THE UPPER TROUGH THAT MOVED THROUGH THU. HAVE HIGHS ON FRI IN THE MID 40S NEAR LAKE SUPERIOR TO THE MID 50S ALONG THE WI BORDER. LOW CONFIDENCE GOING INTO THE WEEKEND AS THE 00Z/18 GFS SHOWS WAA RAIN/SNOW LATE FRI INTO SAT WHILE THE 12Z/17 ECMWF IS DRY. MODELS ALL KEEP 850MB TEMPS AOB 0C THROUGH THE WEEKEND. WILL RUN WITH A BLEND OF MODELS GIVEN THE UNCERTAINTY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 736 AM EDT MON APR 18 2016 AS COOLER AND MOISTER AIR ARRIVES N-S LATER THIS MORNING INTO THE AFTERNOON... EXPECT MVFR CONDITIONS TO DEVELOP UNDER A SHARPENING LOW LEVEL INVERSION. SOME IFR CIGS MAY ALSO BE POSSIBLE AT SAW...WHERE THE LOW LEVEL NE FLOW WILL HAVE A GREATER UPSLOPE COMPONENT...BUT CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE IN THE FCST. THE ARRIVAL OF DRIER AIR AFT 19/00Z WILL RESULT IN LIFTING CIGS AT CMX AND TOWARD THE END OF THE TAF PERIOD AT SAW. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 457 AM EDT MON APR 18 2016 EXPECT NE WINDS OF 15 TO 25 KNOTS TO GRADUALLY WEAKEN THIS AFTERNOON BEFORE HIGH PRESSURE BRINGS LIGHT WINDS THROUGH WEDNESDAY. A TROUGH WILL TRACK SOUTHEASTWARD ACROSS LAKE SUPERIOR ON THURSDAY...BRINGING A QUICK ROUND OF N WINDS OF 20 TO 25 KNOTS. EXPECT N WINDS TO CONTINUE THROUGH FRIDAY AS HIGH PRESSURE SETTLES TO THE NW. && .HYDROLOGY... ISSUED AT 333 AM EDT MON APR 18 2016 CONTINUING TO MONITOR A COUPLE OF RIVERS NEARING ACTION (BANKFULL) STAGE...THE LOWER PORTION OF THE STURGEON RIVER (BARAGA/HOUGHTON COUNTY) AND THE TRAP ROCK RIVER. EVEN IF THESE RIVERS EXCEED ACTION STAGE...THEY ARE NOT ANTICIPATED TO EXCEED MINOR FLOOD STAGE. OVERALL VERY MINOR IMPACTS FOR SPRING SNOWMELT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...JLB MARINE...JLB HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
500 AM EDT MON APR 18 2016 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 457 AM EDT MON APR 18 2016 WV IMAGERY AND RAP ANALYSIS INDICATED A PERSISTENT BLOCKING PATTERN ACROSS THE CONUS WITH VEERING WNW MID/UPPER LEVEL FLOW THROUGH NRN ONTARIO IN RESPONSE TO A RIDGE BUILDING INTO SRN ALBERTA/SASK. AT THE SFC...A COLD FRONT HAD MOVED THROUGH LAKE SUPERIOR AND WAS SLOWLY SINKING THROUGH NRN UPPER MI. LIGHT PCPN ASSOCIATED WITH 850- 600 MB FGEN AND DEEPER SATURATION WAS MAINLY NORTH OF LAKE SUPERIOR. HOWEVER...SCT/ISOLD LIGHT SHOWERS OR SPRINKLES HAVE ALSO DEVELOPED OVER LAKE SUPERIOR TO NEAR THE KEWEENAW. TODAY... MODELS SUGGEST THAT THE FRONT WILL MOVE THROUGH MOST OF UPPER MI BY 18Z AND THROUGH THE FAR SOUTH BY 21Z WITH A CONTINUED TREND TOWARD A SLOWER ARRIVAL OF PCPN ASSOCIATED WITH THE FGEN LAGGING WELL TO THE NORTH OF THE FRONT. THERE MAY BE A FEW SPRINKLES THIS MORNING BUT THE BEST CHANCE FOR MEASURABLE RAIN WILL BE MAINLY OVER THE KEWEENAW THIS MORNING AND THE REST OF NORTHERN UPPER MI THIS AFTERNOON. WITH THE WEAK DISORGANIZED FORCING AS THE STRONGER FGEN SLIDES OFF TO THE EAST OF LAKE SUPERIOR AND LIMITED MOISTURE INFLOW...ONLY CHANCE POPS WERE MENTIONED. ANY RAINFALL AMOUNTS WILL BE LIGHT...A TENTH OF AN INCH OR LESS. NRLY WINDS WILL KEEP HIGHS IN THE 40S OVER THE NORTH BUT WITH THE SLOWER FRONT...TEMPS TO AROUND 70 ARE EXPECTED AGAIN OVER THE SOUTH. TONIGHT...SOME LOW END POPS ASSOCIATED WITH THE FRONT WILL LINGER THIS EVENING...MAINLY OVER THE SOUTH. EXPECT THAT RAIN ASSOCIATED WITH A TROUGH AND BAND OF MOISTURE MOVING THROUGH THE UPPER MS VALLEY WILL REMAIN TO THE SW OF THE CWA...ESPECIALLY GIVEN DRY ERLY LOW LEVEL FLOW ASSOCIATED WITH THE RIDGE BUILDING INTO THE NRN LAKES. && .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 333 AM EDT MON APR 18 2016 MAY SEE SOME LIGHT RAIN SHOWERS BRUSHING FAR WRN UPPER MI TUE INTO TUE NIGHT DUE TO WAA/ISENTROPIC ASCENT BETWEEN A SFC HIGH E OF THE CWA AND PLAINS LOW PRESSURE. UPPER RIDGING OVER THE CWA AND ON THE E SIDE OF AN UPPER LOW OVER THE WRN PLAINS WILL KEEP MOST OF THE AREA DRY TUE AND TUE NIGHT. AN UPPER LOW MOVING THROUGH NRN CANADA WILL CAUSE A SHORTWAVE TO MOVE INTO THE NRN U.S. AND SHEAR THE PLAINS UPPER LOW INTO A TROUGH THAT SHIFTS ACROSS THE CWA WED NIGHT/THU. THIS WILL BRING LIGHT RAIN CHANCES TO THE ENTIRE AREA WED INTO THU. FRI LOOKS DRY FOR THE MOST PART (NEWEST GFS RUN NOW COMING IN WITH SOME RAIN/SNOW OVER THE W LATE...BUT ALL OTHER MODELS ARE DRY) AS SFC HIGH PRESSURE MOVES IN. CERTAINLY WILL BE COOLER AS 850MB TEMPS DROP NEAR OR BELOW 0C BEHIND THE UPPER TROUGH THAT MOVED THROUGH THU. HAVE HIGHS ON FRI IN THE MID 40S NEAR LAKE SUPERIOR TO THE MID 50S ALONG THE WI BORDER. LOW CONFIDENCE GOING INTO THE WEEKEND AS THE 00Z/18 GFS SHOWS WAA RAIN/SNOW LATE FRI INTO SAT WHILE THE 12Z/17 ECMWF IS DRY. MODELS ALL KEEP 850MB TEMPS AOB 0C THROUGH THE WEEKEND. WILL RUN WITH A BLEND OF MODELS GIVEN THE UNCERTAINTY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 125 AM EDT MON APR 18 2016 VFR CONDITIONS WILL CONTINUE TNGT WITH LLVL DRY DOMINATING. BUT AS COOLER AND MOISTER AIR ARRIVES N-S LATER THIS MRNG INTO THE AFTN... EXPECT MVFR AND PERHAPS EVEN IFR CONDITIONS TO DVLP UNDER SHARPENING LLVL INVRN. THE IFR CIGS ARE MOST LIKELY AT SAW...WHERE THE LLVL NE FLOW WL PRESENT A GREATER UPSLOPE COMPONENT. THE ARRIVAL OF DRIER AIR TOWARD 19/00Z WL RESULT IN CLRG SKIES AT CMX AND TOWARD THE END OF THE TAF PERIOD AT SAW/IWD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 457 AM EDT MON APR 18 2016 EXPECT NE WINDS OF 15 TO 25 KNOTS TO GRADUALLY WEAKEN THIS AFTERNOON BEFORE HIGH PRESSURE BRINGS LIGHT WINDS THROUGH WEDNESDAY. A TROUGH WILL TRACK SOUTHEASTWARD ACROSS LAKE SUPERIOR ON THURSDAY...BRINGING A QUICK ROUND OF N WINDS OF 20 TO 25 KNOTS. EXPECT N WINDS TO CONTINUE THROUGH FRIDAY AS HIGH PRESSURE SETTLES TO THE NW. && .HYDROLOGY... ISSUED AT 333 AM EDT MON APR 18 2016 CONTINUING TO MONITOR A COUPLE OF RIVERS NEARING ACTION (BANKFULL) STAGE...THE LOWER PORTION OF THE STURGEON RIVER (BARAGA/HOUGHTON COUNTY) AND THE TRAP ROCK RIVER. EVEN IF THESE RIVERS EXCEED ACTION STAGE...THEY ARE NOT ANTICIPATED TO EXCEED MINOR FLOOD STAGE. OVERALL VERY MINOR IMPACTS FOR SPRING SNOWMELT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...KC MARINE...JLB HYDROLOGY...TITUS Area Forecast Discussion...Updated National Weather Service Saint Louis MO 941 PM CDT TUE APR 19 2016 .UPDATE... Issued at 939 PM CDT Tue Apr 19 2016 Area of rain/embedded thunderstorms should continue to slowly weaken and drift northward overnight tonight. Do not expect much if any in the way of activity after midnight tonight. Next round of at least scattered showers/storms will try and move north/northeast from south-central/southeast Missouri early Wednesday morning. Adjusted PoPs for the rest of tonight and also raised low temperatures a couple of degrees in most locations due to high dewpoints and clouds. Gosselin && .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
  [top] Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 641 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 641 PM CDT TUE APR 19 2016 VFR conditions this evening are not expected to last as showers will move northeast across the region late tonight into Wednesday morning. Low end MVFR to IFR CIGs will spread across the terminals around midnight along with scattered showers that will persist until around sunrise Wednesday. Winds will veer around overnight to the south, southwest and finally west by Wednesday afternoon as the center of a small surface low, that brought the showers, moves northeast through northwest Missouri. CIgs will likely go back to VFR for the afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...Cutter
  [top] Area Forecast Discussion National Weather Service Springfield MO 600 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 557 PM CDT Tue Apr 19 2016 Pesky upper level low underneath blocking omega pattern still sitting off to the west. Scattered showers will remain in the terminals and mainly keeping in VCSH in the forecast. Main aviation concern again will be with the MVFR/IFR conditions. Will see ceilings lower again tonight, eventually into the IFR category at the 3 terminal locations. Conditions will improve during the day Wednesday, back into MVFR/VFR by late in the day. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 310 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...73
Area Forecast Discussion National Weather Service Springfield MO 243 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Frye
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 111 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more positively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 1234 PM CDT TUE APR 19 2016 ...18z Aviation Update... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Frye
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1222 PM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...73
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 558 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 12z TAFs through 12z Wednesday Morning) Issued at 549 AM CDT Tue Apr 19 2016 Band of light rain from near KCOU to KUIN will gradually dissipate this morning. Additional light showers and isolated thunderstorms are possible this afternoon...but sparse coverage precludes placing in TAFS. Ceilings will remain in the VFR category...with generally light and variable winds. Specifics for KSTL: Band of light rain this morning should stay west of KSTL metro...and ceilings will likely remain above 7000 feet for the duration of this TAF period. There is a chance for scattered showers and isolated thunderstorms this afternoon...but coverage is expected to remain sparse. Winds will remain light southwest to south. Browning && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 549 AM CDT TUE APR 19 2016 ...Update to Aviation Discussion for 12Z TAFS... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 543 AM CDT Tue Apr 19 2016 For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will continue at the KJLN TAF site early this morning, then will improve through the day. Ceilings may lower into the MVFR range at the KSGF and KBBG TAF sites this morning before improving this afternoon. Patchy fog will also occur early this morning, especially at the KBBG site. Showers should remain north and south of the TAF sites through this morning, then scattered showers will be possible this afternoon into tonight across the area. Ceilings are expected to lower into the MVFR to IFR range again tonight into early Wednesday morning. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Wise
Area Forecast Discussion National Weather Service Saint Louis MO 349 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1133 PM CDT Mon Apr 18 2016 Scattered showers will affect KCOU and possibly KUIN through the rest of tonight. Showers should be light and likely not pose visibility issues. For the metro terminals...showers should stay west. Ceilings will also lower at KCOU and KUIN into MVFR later on tonight. Some minor visibility reduction is also possible in fog at KCOU. For Tuesday...highest threat of showers/storms again from KCOU to KUIN with the best chance of convection during the late afternoon and early evening hours. Heavier showers/storms could dip visibilities down briefly into IFR. Metro terminals again likely too far to the east. Specifics for KSTL: Lion`s share of shower/thunderstorm activity expected to stay west of terminal through Tuesday night. However...scattered showers/storms are possible Tuesday afternoon/evening in particular. Continue to leave out prevailing group as chances look higher further to the west. Winds will remain light/variable before turning southeasterly again Tuesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 258 AM CDT TUE APR 19 2016 ...Good Chance for Showers Today through Wednesday... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1132 PM CDT Mon Apr 18 2016 Scattered light showers across the area this evening and have affected the terminal locations with some light rain. While showers will be in the vicinity of the aviation sites tonight and Tue morning, the main concern will be with MVFR and IFR conditions. Will see ceilings deteriorate overnight and may build down enough for visibilities to also be affected. Showers will again become more numerous late in the period as the upper level shortwave to the west slowly approaches. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1153 PM CDT MON APR 18 2016 .Discussion... Issued at 332 PM CDT MON APR 18 2016 Water vapor imagery and H5 heights indicate the extensive closed low still positioned over the inter-mountain west with cold front currently moving through eastern Nebraska and Kansas, extending down into the Texas panhandle. At the regional level, band of heavier precip has moved northeastward through the morning and early afternoon, gradually weakening with time as primary forcing remained north across Iowa. Scattered showers remain on the backside of the main band, and the HRRR has done a great job with the overall precip trend. With a few hundred joules of CAPE, might see an isolated thunderstorm or two with this scattered activity. Western half of the CWA should see a downward trend in activity towards evening. Another vorticity maxima will peel off from the main low late tonight into Tuesday morning. Cold front looks to stall across the region from southwest to northeast Missouri. Greater chances for precip will focus near this diffuse cold front and with 600-800 J/kg of CAPE forecast Tuesday afternoon, expect to see thunderstorm development by early afternoon. Showers and thunderstorms expected once again Wednesday in somewhat of a wash-rinse-repeat cycle. Upper low finally begins to eject into the Plains Tuesday night into Wednesday, eventually merging into the northern stream flow. As the trough passes to the north of the region, we could see a few more showers and thunderstorms into Thursday. Upper level ridging will build into the central conus as we head into the weekend, bringing warm temperatures and relatively quiet weather. The next system to watch will be a trough ejecting out of the central Rockies the beginning of the next work week. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...PMM Aviation...MJ
AREA FORECAST DISCUSSION
NWS HASTINGS NE
655 PM CDT TUE APR 19 2016 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 251 PM CDT TUE APR 19 2016 THE SHORT TERM PERIODS WILL FEATURE CLOUDY CONDITIONS WITH PERIODS OF RAIN UNDER THE INFLUENCE OF AN UPPER CYCLONE WHICH ENCOMPASSES MUCH OF THE INTERIOR CONUS. THE CENTER OF THE UPPER LOW WAS LOCATED IN EAST CENTRAL COLORADO EARLY THIS AFTN WITH A LEAD WAVE LIFTING OUT OF THE SYSTEM ACROSS KS INTO NEB. A SWATH OF RAIN ASSOCIATED WITH THE WAVE WAS LIFTING NORTHEAST FROM WESTERN KANSAS AND WILL IMPACT OUR REGION THIS EVENING...WITH RAIN INCREASING IN COVERAGE. THE RAIN IS EXPECTED TO BECOME FAIRLY WIDESPREAD TONIGHT AS THE COLORADO LOW MOVES ONTO THE PLAINS PHASING WITH THE LEAD WAVE WITH DEFORMATION/WRAPAROUND RAINFALL MIGRATING ACROSS NEB/KS THRU WEDNESDAY. THERE ARE SOME MODEL DIFFERENCES ON TIMING/PLACEMENT OF THE MID LEVEL LOW ON WEDNESDAY AND PREFER THE SLOWER SOLUTIONS OF THE GFS/ECMWF THAN THE QUICKER NAM. INSTABILITY PARAMETERS INCREASE TO SOME DEGREE WEDNESDAY AND MAINTAINED POTENTIAL FOR ISOLATED THUNDERSTORMS. HAVE SOME CONCERNS FOR THE POTENTIAL FOR FOG DEVELOPMENT TONIGHT FOR LOCATIONS WHERE RAIN IS NOT FALLING...HOWEVER OVERALL PROBABILITIES FOR THIS ARE RELATIVELY LOW AT THIS TIME. THE PCPN AND CLOUD COVER WILL HOLD TEMPS DOWN ACROSS OUR NORTHERN ZONES WEDNESDAY WHILE FARTHER SOUTH INTO KS...TEMPS WILL BE MILDER WHERE DRIER CONDITIONS AND A FEW BREAKS IN CLOUD SHLD ALLOW READINGS TO REACH THE LOW/MID 60S. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 251 PM CDT TUE APR 19 2016 THE UPPER LEVEL LOW THAT HAS BEEN AFFECTING THE AREA FOR THE PAST FEW DAYS WILL BE EAST OF THE AREA WEDNESDAY NIGHT. THERE IS A SHORT WAVE THAT SWINGS THROUGH WEDNESDAY NIGHT. WITH THE WAVE...EXPECT THERE TO BE SOME SHOWERS AND ISOLATED THUNDERSTORMS WEDNESDAY EVENING BUT LATER WEDNESDAY NIGHT THERE IS LITTLE TO NO CAPE AND ANY LINGERING PRECIPITATION SHOULD JUST BE SHOWERS. MODELS HAVE SOME DIFFERENCES IN THE LOCATION OF THE UPPER LOW AND HOW MUCH PRECIPITATION MOVES IN FROM THE NORTH DURING THE NIGHT. ALL OF THE MODELS HAVE SOME DURING THE EVENING...BUT OVERNIGHT THE NAM AND GFS BOTH HAVE DRY WHILE THE ECMWF HAS A LITTLE LINGERING. HAVE KEPT A LITTLE IN THE NORTHEAST. THURSDAY THROUGH SATURDAY NIGHT AN UPPER LEVEL RIDGE MOVES THROUGH THE PLAINS. THURSDAY THERE WILL BE A SURFACE HIGH PRESSURE SYSTEM THAT BUILDS INTO THE AREA. THIS WILL CLEAR THE CLOUDS OUT OF THE AREA AND THE WINDS WILL BE FAIRLY LIGHT. AS THE SURFACE HIGH MOVES TO THE EAST FRIDAY...THE WINDS WILL INCREASE FROM THE SOUTH ON FRIDAY AND CONTINUE INTO SATURDAY. THE SOUTH WINDS WILL HELP TO WARM TEMPERATURES. THE NEXT UPPER LEVEL LOW WILL START TO AFFECT THE AREA SUNDAY AND CONTINUE THROUGH TUESDAY. THE SOUTH WINDS LATE IN THE WEEK BRING IN ADDITIONAL MOISTURE AND AS THE FIRST UPPER LEVEL WAVE FROM THE LOW MOVES INTO THE AREA THERE IS A CHANCE FOR SOME SHOWERS AND THUNDERSTORMS DEVELOPING MAINLY SUNDAY AFTERNOON. THE UPPER LOW MOVES SLOWLY TO THE EAST THROUGH THE NORTHERN PLAINS...BUT AS THE SURFACE LOW MOVES EAST A COLD FRONT MOVES INTO THE AREA SUNDAY NIGHT INTO MONDAY. THIS SHOULD BE THE FOCUS OF THUNDERSTORMS...BUT MODELS HAVE ONLY MINIMAL QPF ACROSS THE AREA. MODELS HAVE SOME DIFFERENCES AGAIN FOR MONDAY NIGHT INTO TUESDAY. THE ECMWF MOVES THE FIRST UPPER LEVEL LOW TO THE EAST AND BRINGS ANOTHER INTO THE AREA WHILE THE GFS KEEPS THE NEXT LOW FURTHER TO THE WEST. HAVE KEPT FAIRLY LOW POPS SUNDAY THROUGH TUESDAY BUT WITH THE VARIABILITY OF THE MODELS HAVE SOME CONCERNS WHEN AND HOW MUCH PRECIPITATION THERE WILL BE. && .AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 650 PM CDT TUE APR 19 2016 DETERIORATING CONDITIONS ARE EXPECTED AT BOTH TERMINALS AS INCREASED MOISTURE FROM THE SOUTH WILL RESULT IN SOME LIGHT BR AND -RA THIS EVENING...WITH CEILINGS LOWERING TO NEAR LIFR LEVELS BY EARLY WEDNESDAY MORNING. IN FACT...COULD SEE SOME DENSE FOG DEVELOPMENT TOWARDS THE MORNING ON THE WESTERN EDGE OF THE RAIN BANDS...WITH KEAR BEING MOST LIKELY AFFECTED. THE LATEST RUN OF THE HRRR INDICATES THIS POTENTIAL TOWARDS DAYBREAK...SO WILL NEED TO CONTINUE TO MONITOR ITS DEVELOPMENT OVERNIGHT. OTHERWISE... CONTINUED BANDS OF LIGHT RAIN AND POSSIBLY EVEN A THUNDERSTORM ARE POSSIBLE AT BOTH TERMINALS DURING THE DAYTIME HOURS TOMORROW...WITH THE WIND SHIFTING AND BECOMING NORTHWESTELRY NEAR 10 KTS BY MIDDAY. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...FAY LONG TERM...JCB AVIATION...ROSSI
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
632 PM CDT TUE APR 19 2016 .SYNOPSIS... ISSUED AT 259 PM CDT TUE APR 19 2016 A PESKY H5 LOW REMAINS NEARLY STATIONARY ACROSS THE CENTRAL ROCKIES...WHERE IT HAS BEEN FOR THE PAST 3-4 DAYS. CURRENT SATELLITE IMAGERY...FINALLY HAS THIS FEATURE BEGINNING TO PUSH SLOWLY TO THE NORTHEAST INTO NERN COLORADO. RIDGING ACROSS THE EASTERN HALF OF THE CONUS HAS FINALLY BEGUN TO DE AMPLIFY...WHICH WILL ALLOW THIS FEATURE TO CONTINUE TO LIFT SLOWLY EAST OVER THE NEXT 24 TO 36 HOURS...BEFORE ACCELERATING AND BEING ABSORBED INTO LOW PRESSURE OVER HUDSON BAY. IN THE MEANTIME...AN A AREA OF SHOWERS...JUST TO THE EAST OF THE LOW HAS BEGUN TO LIFT OVER THE KS/NEBR BORDER INTO SWRN NEBRASKA. THIS AREA OF PCPN CONTINUES TO HIT DRY AIR AS IT MOVES NORTH...AND IS HAVING A HARD TIME MAKING IT INTO THE LBF CWA THIS AFTERNOON. ELSEWHERE...WHERE CLOUDINESS WAS ABSENT EARLIER TODAY...IT HAS SINCE CLOUDED UP THIS AFTERNOON AS INSTABILITY CU HAS DEVELOPED ACROSS THE FORECAST AREA. UNDER MOSTLY CLOUDY SKIES...2 PM CDT TEMPS RANGED FROM 50 AT IMPERIAL...TO 57 AT VALENTINE. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 259 PM CDT TUE APR 19 2016 SHOWERS HAVING A HARD TIMING MAKING IT NORTH OF THE NEB/KS BOARDER. THE VERY DRY AIR MID LAYER IS KEEPING THE ACTIVITY IN KANSAS. CANNOT RULE OUT SOME EVENING SPRINKLES/LIGHT RAIN SHOWERS AS COLD AIR ASSOCIATED WITH THE UPPER LEVEL LOW CAUSES STEEP LAPSE RATES AND ENOUGH INSTABILITY FOR THE CU TO PRODUCE SOME SHOWERS. OVERNIGHT SOME LINGERING SHOWERS WILL BE POSSIBLE BENEATH THE COLD AIR OF THE UPPER LEVEL LOW OVER WESTERN NEBRASKA. PORTIONS OF SW INTO CENTRAL NEBRASKA COULD SEE SOME SHOWERS AS THE DISTURBANCE ROTATING AROUND THE LOW LIFTS OUT OF WESTERN KS. BETTER CHANCES ARE TO THE EAST BUT IT MAY PUSH THIS FAR WEST SO WILL KEEP LOW POPS IN THE FORECAST. ALSO SAW SOME PATCHY FOG OVER CENTRAL NEBRASKA THIS MORNING...AND WITH THE RICH BL MOISTURE...AND A FEW MODELS GUIDANCE SUGGESTING...WILL ADD SOME PATCHY FOG. IF LESS SHOWERS DEVELOP EXPECT TEMPS TO FALL A DEGREE OR TWO MORE AND MORE FOG WILL BE EXPERIENCED. TOMORROW THE UPPER LOW WILL ROTATE ACROSS THE CWA. THIS COLD AIR ALOFT WILL CREATE STEEP LAPSE RATE AND EXPECT THIS ENOUGH FOR SCATTERED SHOWERS. ENOUGH INSTABILITY...POS CAPE AND POCKETS OF NEGATIVE C LIFT INDEX VALUES...SO WILL INCLUDE ISOLD THUNDER. NOTHING SEVERE...HOWEVER WITH THE LOW FREEZING LEVEL AND COLD AIR ALOFT /DUE TO UPPER LEVEL LOW/ SOME SMALL SOFT HAIL CANNOT BE RULED OUT. CLOUDS/SHOWERS WILL KEEP TEMPS ON THE COOL SIDE...HIGHS AROUND 60. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 259 PM CDT TUE APR 19 2016 MID RANGE...WEDNESDAY NIGHT THROUGH FRIDAY...IN THE MID RANGE...LINGERING PCPN WEDS EVENING...FOLLOWED BY TEMPS WILL BE THE MAIN FORECAST CHALLENGE. FOR WEDNESDAY EVENING...THE UPPER LEVEL LOW WILL BEGIN TO TRACK INTO IOWA FROM NEBRASKA. ON THE WESTERN AND NORTHWESTERN PERIPHERY OF THIS SYSTEM...THERE REMAINS THE THREAT FOR DEFORMATION PCPN...PARTICULARLY WEDS EVE. WAS CONCERNED SOMEWHAT ABOUT CONVECTIVE POTENTIAL WEDS AFTN/EVE AND HOW FAR WEST PCPN WILL ACTUALLY DEVELOP OUTSIDE OF THE EXPECTED DEFORMATION BAND. ATTM...H5 TEMPS ARE NOT SUPER COLD AND LI/S ARE MARGINALLY UNSTABLE BY WEDS EVENING. THAT BEING SAID...DECIDED TO LEAVE OUT A MENTION OF PCPN IN CENTRAL AND WRN NEBRASKA WEDS EVENING. ATTM...FELL THE GREATEST THREAT FOR LIGHT PCPN WILL LIE IN THE DEFORMATION ZONE...ORIENTED ACROSS THE EASTERN CWA. DECIDED TO KEEP POPS ON THE SLIGHT CHANCE SIDE GIVEN THE LACK OF STRONG INSTABILITY. ON THURSDAY...THE UPPER LEVEL LOW WILL SPLIT WITH ONE PIECE HEADING EAST AND A SECOND DROPPING SOUTH INTO OKLAHOMA. RIDGING ACROSS THE CENTRAL ROCKIES WILL BEGIN TO BUILD EAST THURSDAY...HELPING TO BOOST TEMPS BACK TO MORE SEASONAL LEVELS. AFTER HIGHS IN THE MID TO UPPER 60S ON THURSDAY...READINGS WILL PUSH INTO THE 70S FOR FRIDAY. LOWS WILL BE COOL HOWEVER WEDS NIGHT AND THURSDAY NIGHT AS WE WILL NOT SEE ANY DECENT LOW LEVEL MOISTURE RETURN THROUGH SATURDAY. LONG RANGE...FRIDAY NIGHT THROUGH TUESDAY...RIDGING ALOFT WILL BE DOMINANT THROUGH SATURDAY WITH VERY WARM TEMPERATURES EXPECTED SATURDAY WITH READINGS IN THE UPPER 70S TO NEAR 80. BY SATURDAY NIGHT...THE FIRST OF TWO...UPPER LEVEL LOWS WILL TRACK ACROSS THE INTER MOUNTAIN WEST ONTO THE CENTRAL AND NORTHERN PLAINS. THE FIRST...WILL TRACK INTO SOUTH DAKOTA...WHICH WOULD LIMIT PCPN CHANCES ACROSS WESTERN AND NORTH CENTRAL NEBRASKA...AND WOULD PUT THE FA IN THE DRY SLOT. THE SECOND SYSTEM WILL CROSS INTO THE CENTRAL ROCKIES ON TUESDAY. THE MID RANGE MODELS ARE INDICATING DECENT MOISTURE ADVECTION OUT AHEAD OF THIS SYSTEM...TUESDAY ACROSS THE HIGH PLAINS...AND SEE NO REASON TO STRAY FROM CHANCE POPS MON NIGHT/TUESDAY ACROSS THE CWA. HIGHS MONDAY AND TUESDAY WILL COOL BACK TO THE 60S AND UPPER 50S GIVEN EXPECTED CLOUD COVER IN ASSOC WITH THE UPPER LEVEL SYSTEM. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 632 PM CDT TUE APR 19 2016 THE RAP AND MET/MAV GUIDANCE ARE GIVING A PRETTY GOOD FOG SIGNAL TONIGHT BEGINNING AROUND 06Z THROUGH 14Z WEDNESDAY. THE AREA OF CONCERN COVERS I-80 AND SOUTH. THIS MAY LEAD TO IFR/LIFR CONDITIONS BUT THE SREF DOES NOT SUPPORT THIS. MVFR/IFR VISIBILITY IS MORE LIKELY...THE MET GUIDANCE SUGGESTS A SHORT PERIOD OF LIFR AROUND 12Z LASTING 1 TO 3 HOURS. THE PROBABILITY OF LOW OR VERY LOW CIGS IS UNCERTAIN AT THIS TIME. && .HYDROLOGY... ISSUED AT 326 PM CDT MON APR 18 2016 THE THREAT FOR HEAVY RAINFALL HAS ENDED...ALTHOUGH SOME LIGHT ADDITIONAL RAINFALL TONIGHT INTO TOMORROW NIGHT WILL BE POSSIBLE. AREA RIVERS AND CREEKS FOR THE MOST PART ONLY SAW MINOR RISES OF TWO FEET OR LESS. STARTING TO WATCH WATER MOVING DOWN THE SOUTH PLATTE RIVER OUT OF COLORADO. AT THIS TIME IT APPEARS RISE WILL GO ABOVE FORECAST ISSUANCE STAGE IN THE COMING DAYS...HOWEVER SHOULD REMAIN WELL BELOW FLOOD STAGE. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BUTTLER SHORT TERM...MASEK LONG TERM...BUTTLER AVIATION...CDC HYDROLOGY...MASEK
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1154 PM CDT SUN APR 17 2016 .SYNOPSIS... ISSUED AT 330 PM CDT SUN APR 17 2016 AS OF 20Z...THE UPPER LOW HAS INCHED NORTHWARD INTO WESTERN COLORADO BUT HAS STALLED ONCE AGAIN. THE SURFACE COLD FRONT HAS MOVED INTO EASTERN NEBRASKA...KEEPING ALL OF THE LBF CWA IN THE COOL SECTOR AND WITH NORTHERLY LOW LEVEL FLOW. TEMPERATURES HAVE STRUGGLED TO LEAVE THE 30S FOR MOST AREAS WEST OF U.S. HWY 83...WHERE SNOW MIXED WITH RAIN THROUGH THE MID MORNING HOURS. THE DRY SLOT STARTED TO THIN THE CLOUDS FROM KIML TO KIEN THIS AFTERNOON...BUT THE NEXT WAVE OF PRECIPITATION INCREASED IN COVERAGE AND INTENSITY OVER CENTRAL NEBRASKA. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 330 PM CDT SUN APR 17 2016 THIS EVENING AND TONIGHT...FOLLOWED THE HRRR AN RAP CLOSELY WITH POP COVERAGE AS THE MODELS HAVE PORTRAYED THE PRECIP PLACEMENT FAIRLY WELL THIS AFTERNOON...SO CONTINUED DEFINITE POPS ALONG/EAST OF HWY 83. SFC OBS AT KODX HAVE BEEN TEMPORARILY REPORTING RA AND FORECAST SOUNDINGS INDICATING SUFFICIENT LIFT TO SUPPORT HEAVIER SHOWERS...SO ADDED MODERATE RAIN MENTION THROUGH 06Z. GIVEN MAX TEMPS IN THE MID 30S ACROSS NORTHWEST NEB... MENTIONED RASN AFTER 00Z AND GRADUALLY SPREAD EAST TO ALL AREAS WEST OF KIML-KVTN OVERNIGHT. RAP AND HRRR SOUNDINGS INDICATE MAINLY SN WHILE NAM IS SLIGHTLY WARMER AND SUPPORTS RASN AT KIML AND KOGA. BETTER CONFIDENCE OF ALL SNOW LIES NEAR THE PINE RIDGE...SO CONFINED TO SHERIDAN CO AND SMALL PARTS OF GARDEN AND CHERRY. NOT EXPECTING AS MUCH MOISTURE NORTHWEST NEB AS SAT NIGHT DUE TO DRY SLOT. WITH TEMP PROFILES HUGGING THE FREEZING LINE IN THE FIRST 200HPA...DRY AIR REMAINING ABOVE THAT LAYER...AND LITTLE LIFT...SNOW AMOUNTS ARE ONE INCH OR LESS. SMALL SLR WILL ALSO HELP LIMIT ACCUMULATION. MONDAY...MADE LITTLE CHANGE TO MAX TEMPS AS FORECAST HIGHS ARE SIMILAR TO MAV AND MET GUIDANCE. HIGHS MAY BE A LITTLE OVERDONE ACROSS THE NORTH WHERE CLOUDS WILL HANG AROUND ALL DAY AND POPS ARE GREATER. HIGHS MAY BE UNDERDONE ACROSS THE SOUTHERN PANHANDLE WHERE SOME CLOUD BREAKS ARE POSSIBLE LATE AFTERNOON AND NAM SHOWS WEAK WAA ALONG WITH A DOWNSLOPE COMPONENT AT H85. REDUCED POPS THROUGHOUT THE DAY ACROSS THE SOUTH AS THE UPPER LOW FILLS AND MOVES NORTHEAST A BIT...PULLING IN DRIER AIR...VERY NOTICEABLE 700HPA AND ABOVE. NAM SOUNDINGS AT KLBF ALSO INCREASE THE DEW POINT DEPRESSION AND INDICATE OVERALL SUBSIDENCE BY 18Z. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 PM CDT SUN APR 17 2016 MONDAY NIGHT INTO TUESDAY THE UPPER LEVEL IS EXPECTED TO FINAL BEGIN TO PUSH EAST ONTO THE HIGH PLAINS. DRY SLOT ACROSS THE AREA MONDAY NIGHT WITH LITTLE RAINFALL. CLOUDS SHOULD ALSO BE ON THE DECREASE...WITH AT LEAST SOME BREAKS AND WILL MONITOR FOR POSSIBLY CLEARING. DEPENDS ON HOW MUCH CLEARING...TEMPS SHOULD FALL INTO THE 30S...WITH ISOLATED AREAS AROUND 30 IF CLEAR SKIES PERSISTS FOR SEVERAL HOURS. ON TUESDAY AS THE LOW MOVES OVERHEAD...STEEP LAPSE RATE DEVELOP. ANY SUNSHINE WILL HELP WARM THINGS UP...WITH CU EXPECTED TO QUICKLY BECOME WIDESPREAD. SHOULD TAKE LONG AND SHOWERS WILL DEVELOP AND WILL HAVE TO MONITOR FOR SOME SMALL SOFT HAIL/GRAUPEL AS THE FREEZING LEVEL DROPS. SOME JUST NEG C LIFT INDEX INDICATED IN THE MODELS ACROSS THE EASTERN ZONES AND CANNOT RULE OUT A FEW RUMBLES OF THUNDER. AS THE LOW CONTINUES TO PUSH EAST...WRAP AROUND MOISTURE WILL CONTINUE TO BRING THE CHANCE FOR AT LEAST ISOLD SHOWERS. OVERNIGHT WITH TEMPS COOLING INTO THE MID 30S...MAY SEE A MIX OF RAIN/SNOW ACROSS NORTHWEST NEB...OTHER WISE WARM ENOUGH FOR LIQUID. BY THURSDAY THE LOW IS PROGGED TO BE EAST OF THE AREA WITH A RIDGE TO DEVELOP ACROSS THE WEST. WAA WILL INCREASE THICKNESS AND TEMPS WILL BE ON AN UPWARD TREND...ALSO SHOULD BE DRYING OUT. BY SATURDAY...THE WARMEST DAY...HIGHS WELL INTO THE 70S AND EVEN AROUND 80. BY SATURDAY NIGHT INTO SUNDAY THE NEXT TROUGH DIGS TOWARDS THE 4 CORNERS. SOUTHERLY WINDS WILL HELP INCREASE MOISTURE WITH A SLOW RAISING OF POPS. TIMING STILL AN ISSUE BEING THIS IS DAY 7 AND MAY NEED TO DELAY POPS IN LATER FORECASTS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1154 PM CDT SUN APR 17 2016 MVFR CEILINGS NEAR OVC012 ARE FORECAST AT THE KLBF TERMINAL THROUGH 15Z MONDAY. CEILINGS FCST TO IMPROVE TO VFR AT BKN035 OVC060 BY 18Z MONDAY. AT KVTN...IFR CEILING NEAR OVC009 SHOULD REMAIN IFR UNTIL 14Z MONDAY. AFTER 14Z...MVFR CEILINGS FORECAST. -RA WILL ALSO REMAIN SCATTERED OVERNIGHT MAINLY NEAR AND EAST OF KLBF AND KVTN. && .HYDROLOGY... ISSUED AT 330 PM CDT SUN APR 17 2016 THE LONG DURATION HEAVY RAINFALL APPEARS TO BE GETTING ABSORBED BY WHAT WAS A DRY GROUND. SO FAR AREA CREEKS AND RIVERS HAVE ONLY SEEN MINIMAL RISES. HOWEVER...THE SLOW RUN OFF ALONG WITH ADDITIONAL RAINFALL OVER THE NEXT COUPLE OF DAYS WILL REQUIRED CREEKS AND RIVERS TO BE MONITORED CLOSELY...ESPECIALLY ACROSS SOUTHWEST NEBRASKA...WHERE WIDESPREAD 3 TO 4+ INCHES OF RAINFALL OVER THE PAST 56 HOURS HAVE BEEN RECORDED. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...SNIVELY SHORT TERM...SNIVELY LONG TERM...MASEK AVIATION...ROBERG HYDROLOGY...MASEK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
740 PM EDT TUE APR 19 2016 .SYNOPSIS... A DRY COLD FRONT WILL DROP SOUTH WEDNESDAY MORNING BRINGING COOLER TEMPERATURES. SURFACE HIGH PRESSURE WILL MOVE OFFSHORE THURSDAY AND FRIDAY WITH TEMPERATURES WARMING LATE IN THE WEEK. SHOWERS AND ISOLATED THUNDERSTORMS WILL PRECEDE A COLD FRONT FRIDAY AND FRIDAY NIGHT...WITH SHOWERS LINGERING INTO SATURDAY AS THE FRONT CLEARS THE COAST. A DRYING TREND IS EXPECTED SUNDAY INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... AS OF 730 PM TUESDAY...A LARGE WILDFIRE WEST OF THE TOWN OF BOLIVIA IN BRUNSWICK COUNTY NC HAS SPREAD SMOKE NORTHEASTWARD ACROSS EASTERN BRUNSWICK COUNTY AND RECENTLY INTO NEW HANOVER COUNTY AND WILMINGTON. SOUTHWESTERLY SURFACE WINDS ARE DUE TO THE SEABREEZE WHICH RECENTLY PUSHED NORTHWARD ACROSS WILMINGTON. SYNOPTIC WINDS SHOULD TURN MORE WESTERLY BY 10-11 PM THIS EVENING...PUSHING THE SMOKE OUT OF LELAND AND WILMINGTON. WE HAVE ADDED SMOKE TO THE FORECAST THIS EVENING ACROSS THE WILMINGTON METRO AREA...AND ALL THROUGH THE NIGHT ACROSS EASTERN BRUNSWICK COUNTY. ANALYSIS OF RELATIVE HUMIDITY AND WIND TRENDS DO NOT SUPPORT THE FORMATION OF FOG...AND THIS IS VERY GOOD NEWS AS THE CONCURRENCE OF FOG AND SMOKE CAN LEAD TO "SUPERFOG" WITH NEAR ZERO VISIBILITIES AND DANGEROUS DRIVING CONDITIONS. A DRY COLD FRONT CURRENTLY MOVING SOUTHWARD ACROSS VIRGINIA WILL REACH OUR AREA LATE TONIGHT. AMONG THE VARIOUS MODELS...THE 18Z GFS AND 12Z CANADIAN ARE THE FASTEST...WITH THE 18Z NAM AMONG THE SLOWEST. I AM TRENDING OUR FORECAST TOWARD THE SLOWER GUIDANCE WHICH DELAYS THE TIMING OF THE FRONT BY A FEW HOURS AND PROBABLY PLACES ITS PASSAGE ACROSS GEORGETOWN AND KINGSTREE UNTIL AFTER DAYBREAK WEDNESDAY. ASIDE FROM A WIND SHIFT THERE IS NO SIGNIFICANT WEATHER ASSOCIATED WITH THIS FEATURE. NO SIGNIFICANT CHANGES HAVE BEEN MADE TO LOW TEMPERATURE FORECASTS TONIGHT...CURRENTLY EXPECTED TO REACH 55-60 FOR MOST AREAS. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... AS OF 3 PM TUESDAY...MAIN WEATHER STORY THIS PERIOD IS THE 14-18 DEGREE COOL DOWN ON WEDNESDAY HIGHS COMPARED TO TODAY. NOT THAT THE FRONT IS THIS STRONG BUT LACK OF DOWNSLOPE AND A MARINE INFLUENCE WILL MAKE A WORLD OF DIFFERENCE ON READINGS. THE OTHER STORY OF NOTE IS INCREASING WARM AIR ADVECTION THURSDAY INTO FRIDAY AND A CHANCE FOR A FEW SHOWERS OR A TSTM. TEMPERATURES 4-7 DEGREES MILDER THURSDAY COMPARED TO WEDNESDAY. NO HAZARDS EXPECTED OVER LAND THIS PERIOD ASIDE FROM ISOLATED CLOUD TO GROUND LIGHTNING STRIKES THURSDAY AFTERNOON AND EVENING. PARTIAL SUNSHINE SHOULD WORK IN TANDEM WITH MOISTURE TO PRODUCE ISOLATED CONVECTION THURSDAY WITH LOW-LEVEL CONVERGENCE ADDING BOOST AS WELL. OCEAN SHOWERS AND FORMATION OVER LAND BOTH EXPECTED THU...THOUGH ISOLATED OVERALL. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 3 PM TUESDAY...SOME SLIGHT TIMING DIFFERENCES IN REGARDS TO THE APPROACH OF SURFACE COLD FRONT AND UPPER TROUGH ON FRIDAY. SLOWER MODELS IMPLY THAT A GOOD PART OF THE DAY MAY STAY DRY. BEST RECOURSE AT THIS POINT SEEMS TO BE TO SHOW INCREASING RAIN CHANCES AS THE DAY WEARS ON. THESE TIMING DIFFERENCES ALSO TRANSLATE INTO SATURDAY. NAMELY, THE RAPIDITY WITH WHICH WE DRY OUT REMAINS TO BE SEEN. MOST OF THE DAY APPEARS TO OFFER ONLY MINIMAL RAIN CHANCES ANYWAY. A WEAK HIGH BUILDS OFF THE COAST SUNDAY THROUGH TUESDAY WHILE VERY LOW AMPLITUDE RIDGING DEVELOPS ALOFT. THIS WILL LEAD TO PLENTY OF SUNSHINE AND SEASONABLE WEATHER. && .AVIATION /23Z TUESDAY THROUGH SUNDAY/... AS OF 00Z...SMOKE WILL CREATE REDUCED VSBYS AT KILM OVER THE NEXT FEW HOURS. OTHERWISE EXPECT VFR AT ALL TERMINALS THROUGH THE VALID TAF PERIOD. WITH THE RECENT PASSING OF THE SEABREEZE ALONG THE COAST...A CHANGE IN WIND DIRECTION TO THE SOUTHWEST IS ALLOWING SMOKE FROM A LOCAL FIRE IN BRUNSWICK COUNTY TO INFILTRATE INTO NEW HANOVER COUNTY. THIS IS CURRENTLY CREATING REDUCED VISIBILITIES AT KILM...THUS WILL KEEP MVFR/IFR IN TAF OVER THE NEXT FEW HOURS. ANTICIPATE A WINDSHIFT AROUND 3/4Z TO ALLOW THESE CONDITIONS TO IMPROVE BACK TO VFR AS WESTERLY WINDS LATER THIS EVENING BECOME NORTH-NORTHWESTERLY OVERNIGHT WITH A BACKDOOR COLD FRONT...AOB 8 KTS. ACROSS THE REST OF THE AREA FOR TONIGHT...VFR WILL PREVAIL WITH SCT/BKN CIRRUS. ON WEDNESDAY...SCT/BKN MID TO HIGH CLOUDS WITH INCREASING NORTHEAST WINDS TO AOB 12 KTS AND HIGHER GUSTS AOB 20 KTS AT TIMES. TOWARDS EVENING...EXPECT GUSTS TO SUBSIDE WITH WINDS BECOMING EASTERLY. EXTENDED OUTLOOK...INCREASING MVFR CHANCES BY THURSDAY INTO FRIDAY FROM SHOWERS AND REDUCED CEILINGS. OTHERWISE EXPECT VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 730 PM TUESDAY...BREEZY WINDS BEHIND THIS AFTERNOON`S SEABREEZE ARE ALREADY DIMINISHING AT THE BEACHES...ALTHOUGH OFFSHORE BUOYS ARE INDICATING GUSTS STILL APPROACHING 20 KNOTS. WEST-SOUTHWEST WINDS OF 15G20 KT THIS EVENING WILL TURN NORTHERLY LATE TONIGHT INTO WEDNESDAY MORNING AS A COLD FRONT SLIPS THROUGH FROM THE NORTH. THIS FRONT...CURRENTLY MOVING SOUTH THROUGH VIRGINIA...IS BEST DEFINED IN THE 18Z NAM MODEL AND THE LATEST COUPLE OF HIGH-RES HRRR MODEL RUNS. WE ARE USING A BLEND OF THESE SLOWER MODELS AND IGNORING THE 18Z GFS AND 12Z CANADIAN RUNS WHICH APPEAR TOO FAST. SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... AS OF 3 PM TUESDAY...ROUGH MARINE CONDITIONS TO KICK OFF WEDNESDAY IN WAKE OF A SOUTHWARD MOVING COLD FRONT. NE WINDS 15-25 KT AND 3-6 FOOT SEAS WILL REQUIRE A SMALL CRAFT ADVISORY FOR ALL WATERS WEDNESDAY. BY WED EVENING THE NE SURGE WILL HAVE ALREADY WEAKENED AND THE ADVISORY WILL LIKELY BE JUST A DAYTIME EVENT. SEAS OUTER PORTION AND FRYING PAN 6-7 FEET WEDNESDAY. WIND CHARACTER TO TAKE ON A VEERING AND EASING PROFILE BECOMING SE INTO THURSDAY 10-15 KT AND SEAS 3-4 FT. MARINERS SHOULD CONSIDER A RADAR UPDATE ON THURSDAY WITH ISOLATED SHOWERS AND TSTMS IN THE MARINE MIX. LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 3 PM TUESDAY... COLD FRONT MOVES THROUGH LATE FRIDAY OR FRIDAY NIGHT. THERE WILL NOT BE APPRECIABLE WIND SPEEDS BEFORE OR FOLLOWING ITS PASSAGE THOUGH CONSIDERABLE VARIATION IN WIND DIRECTION IS ANTICIPATED. IN THE WAKE OF THIS BOUNDARY A NORTHEASTERLY FLOW WILL SLOWLY BECOME ESTABLISHED ON THE SOUTHEAST PERIPHERY OF AN AREA OF HIGH PRESSURE. THIS FLOW WILL LAST FOR THE REMAINDER OF THE PERIOD WITH A POSSIBLE TURN TO EAST OR SOUTHEAST ON SUNDAY NIGHT AS THE HIGH STARTS PROGRESSING EASTWARD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT WEDNESDAY FOR AMZ250-252-254-256. && $$ SYNOPSIS...MBB NEAR TERM...TRA SHORT TERM...MJC LONG TERM...MBB AVIATION...SGL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
934 PM CDT TUE APR 19 2016 .UPDATE... ISSUED AT 929 PM CDT TUE APR 19 2016 LOWERED MINIMUM TEMPERATURES OVERNIGHT IN THE SOUTHWEST SLIGHTLY AS QUITE A BIT OF CLEARING HAS OCCURRED THIS EVENING. MINOT AND JAMESTOWN OBSERVATIONS HAVE NOTED SOME PATCHY FOG IN THE PAST HOUR OR SO...THEREFORE DID INTRODUCE PATCHY FOG IN PARTS OF THE CENTRAL AND EAST EARLIER THAN ORIGINALLY ANTICIPATED. OTHER THAN THAT...THE FORECAST LOOKS TO BE ON TRACK. UPDATE ISSUED AT 640 PM CDT TUE APR 19 2016 FORECAST LOOKS MAINLY ON TRACK SO NO MAJOR CHANGES WERE NEEDED FOR THIS UPDATE. DID INCREASE PATCHY FOG TO AREAS OF FOG FROM 06Z TO 12Z OVERNIGHT EAST OF THE MISSOURI RIVER...REASONING BASED ON RECENT MOISTURE...SOUTHERLY FLOW...AND FORECAST LIGHT SURFACE WINDS. THE LAST SEVERAL ITERATIONS OF THE OPERATIONAL HRRR ALSO SEEM TO SUGGEST THIS SOLUTION. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 331 PM CDT TUE APR 19 2016 FOCUS IS ON THE EXITING UPPER LEVEL LOW OVER THE ROCKIES AND FOG WEDNESDAY MORNING. THE SEMI STATIONARY UPPER LEVEL LOW PRESSURE OVER THE ROCKIES IS BEGINNING TO PROPAGATE EAST...CUTTING OFF MOIST FLOW INTO THE NORTHERN PLAINS. ONLY A FEW SHOWERS REMAIN ACROSS SOUTHEAST PARTS OF NORTH DAKOTA AND WILL FURTHER DIMINISH THROUGH THE NIGHT. DRIER AIR OVER CENTRAL SOUTH DAKOTA AND SOUTH CENTRAL NORTH DAKOTA HAS USHERED IN SOME MOSTLY CLEAR SKIES. SHORT RANGE MODELS WERE HAVING A HARD TIME PICKING UP ON THIS FEATURE...THUS LEANED MORE ON LATEST SATELLITE FOR THE SHORT TERM SKY FORECAST. SHORT RANGE MODELS STILL DEVELOP FOG ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA TONIGHT INTO WEDNESDAY MORNING. WITH THAT SAID HAVE LEFT PATCHY FOG IN FOR ALL OF CENTRAL AND WESTERN NORTH DAKOTA DUE TO LIGHT WINDS AND AMPLE MOISTURE FROM RECENT RAINS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 331 PM CDT TUE APR 19 2016 FOCUS IN THE LONG TERM IS ON THE CHANCES FOR PRECIPITATION SATURDAY NIGHT INTO EARLY NEXT WEEK. THE 12 UTC GUIDANCE CONTINUES TO SHOW AN UPPER LEVEL RIDGE BUILDING INTO THE NORTHERN PLAINS THURSDAY...USHERING IN DRY CONDITIONS THURSDAY THROUGH SATURDAY AFTERNOON. LONGER RANGE MODELS HAVE COME INTO BETTER AGREEMENT ON THE NEXT WEATHER MAKER FOR THE NORTHERN PLAINS. LIKE THIS PREVIOUS SYSTEM A CUT OFF UPPER LEVEL LOW WILL SET UP OVER THE ROCKIES WITH MOIST FLOW MOVING NORTH INTO NORTH DAKOTA. AT THIS TIME THE WEEKEND SYSTEM APPEARS TO BE MORE PROGRESSIVE THAN THIS PAST WET WEATHER MAKER. CHANCES RAIN AND EVEN POSSIBLY SNOW ON THE BACK SIDE START SATURDAY NIGHT AND LAST INTO TUESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 640 PM CDT TUE APR 19 2016 LOW CLOUDS ARE STILL HANGING AROUND KMOT AND KJMS...WHILE THEY HAVE SCATTERED OUT AT ALL OTHER SITES. THIS LOW CLOUD SHIELD SHOULD CONTINUE TO DISSIPATE FROM THE SOUTHWEST TO THE NORTHEAST THROUGH THE EVENING HOURS. THE MAIN CONCERN OVERNIGHT WILL RESIDE EAST OF THE MISSOURI RIVER AS AREAS OF DENSE FOG MAY DEVELOP...EFFECTING MAINLY KJMS AFTER 03Z OR SO. PATCHY FOG WILL BE POSSIBLE AT ALL OTHER SITES. WINDS WILL GENERALLY REMAIN LIGHT THROUGHOUT THE PERIOD WITH FOG DIMINISHING BY LATE WEDNESDAY MORNING...WHEN VFR CONDITIONS SHOULD PREVAIL THROUGH THE REST OF THE FORECAST PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ZH SHORT TERM...MM LONG TERM...MM AVIATION...ZH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
647 PM CDT TUE APR 19 2016 .UPDATE... ISSUED AT 640 PM CDT TUE APR 19 2016 FORECAST LOOKS MAINLY ON TRACK SO NO MAJOR CHANGES WERE NEEDED FOR THIS UPDATE. DID INCREASE PATCHY FOG TO AREAS OF FOG FROM 06Z TO 12Z OVERNIGHT EAST OF THE MISSOURI RIVER...REASONING BASED ON RECENT MOISTURE...SOUTHERLY FLOW...AND FORECAST LIGHT SURFACE WINDS. THE LAST SEVERAL ITERATIONS OF THE OPERATIONAL HRRR ALSO SEEM TO SUGGEST THIS SOLUTION. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 331 PM CDT TUE APR 19 2016 FOCUS IS ON THE EXITING UPPER LEVEL LOW OVER THE ROCKIES AND FOG WEDNESDAY MORNING. THE SEMI STATIONARY UPPER LEVEL LOW PRESSURE OVER THE ROCKIES IS BEGINNING TO PROPAGATE EAST...CUTTING OFF MOIST FLOW INTO THE NORTHERN PLAINS. ONLY A FEW SHOWERS REMAIN ACROSS SOUTHEAST PARTS OF NORTH DAKOTA AND WILL FURTHER DIMINISH THROUGH THE NIGHT. DRIER AIR OVER CENTRAL SOUTH DAKOTA AND SOUTH CENTRAL NORTH DAKOTA HAS USHERED IN SOME MOSTLY CLEAR SKIES. SHORT RANGE MODELS WERE HAVING A HARD TIME PICKING UP ON THIS FEATURE...THUS LEANED MORE ON LATEST SATELLITE FOR THE SHORT TERM SKY FORECAST. SHORT RANGE MODELS STILL DEVELOP FOG ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA TONIGHT INTO WEDNESDAY MORNING. WITH THAT SAID HAVE LEFT PATCHY FOG IN FOR ALL OF CENTRAL AND WESTERN NORTH DAKOTA DUE TO LIGHT WINDS AND AMPLE MOISTURE FROM RECENT RAINS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 331 PM CDT TUE APR 19 2016 FOCUS IN THE LONG TERM IS ON THE CHANCES FOR PRECIPITATION SATURDAY NIGHT INTO EARLY NEXT WEEK. THE 12 UTC GUIDANCE CONTINUES TO SHOW AN UPPER LEVEL RIDGE BUILDING INTO THE NORTHERN PLAINS THURSDAY...USHERING IN DRY CONDITIONS THURSDAY THROUGH SATURDAY AFTERNOON. LONGER RANGE MODELS HAVE COME INTO BETTER AGREEMENT ON THE NEXT WEATHER MAKER FOR THE NORTHERN PLAINS. LIKE THIS PREVIOUS SYSTEM A CUT OFF UPPER LEVEL LOW WILL SET UP OVER THE ROCKIES WITH MOIST FLOW MOVING NORTH INTO NORTH DAKOTA. AT THIS TIME THE WEEKEND SYSTEM APPEARS TO BE MORE PROGRESSIVE THAN THIS PAST WET WEATHER MAKER. CHANCES RAIN AND EVEN POSSIBLY SNOW ON THE BACK SIDE START SATURDAY NIGHT AND LAST INTO TUESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 640 PM CDT TUE APR 19 2016 LOW CLOUDS ARE STILL HANGING AROUND KMOT AND KJMS...WHILE THEY HAVE SCATTERED OUT AT ALL OTHER SITES. THIS LOW CLOUD SHIELD SHOULD CONTINUE TO DISSIPATE FROM THE SOUTHWEST TO THE NORTHEAST THROUGH THE EVENING HOURS. THE MAIN CONCERN OVERNIGHT WILL RESIDE EAST OF THE MISSOURI RIVER AS AREAS OF DENSE FOG MAY DEVELOP...EFFECTING MAINLY KJMS AFTER 03Z OR SO. PATCHY FOG WILL BE POSSIBLE AT ALL OTHER SITES. WINDS WILL GENERALLY REMAIN LIGHT THROUGHOUT THE PERIOD WITH FOG DIMINISHING BY LATE WEDNESDAY MORNING...WHEN VFR CONDITIONS SHOULD PREVAIL THROUGH THE REST OF THE FORECAST PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ZH SHORT TERM...MM LONG TERM...MM AVIATION...ZH
AREA FORECAST DISCUSSION
NWS Tulsa OK
622 PM CDT TUE APR 19 2016 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. IFR/MVFR cigs and MVFR vsbys in light rain and fog will prevail for much of the TAF period at all sites. A slow moving upper system will finally push east later in the TAF period...with VFR elements expected to return from west to east late in the TAF period. && .PREV DISCUSSION... /ISSUED 258 PM CDT TUE APR 19 2016/ DISCUSSION... Persistent areas of light rain have plagued northeast Oklahoma much of Today as strong isentropic lift and a mid-level shortwave easing across the area have combined forces to wring the plentiful moisture out of the air. The HRRR has this activity breaking down over the next few hours in advance of the next round of showers and thunderstorms. The next round of showers and thunderstorms is expected to move into eastern Oklahoma later this evening as the upper level low that has been stuck over the Rockies finally begins to move off to the east. This activity is expected to be east and south of the forecast area by sunrise on Wednesday. Additional showers and thunderstorms will be possible Wednesday night into Thursday as a secondary upper level low scoots across the area. The best chances of showers and thunderstorms will be south of Interstate 40.The chances of showers and thunderstorms end Thursday evening as a storm system finally moves east of the area. High pressure aloft and at the surface prevails through much of the weekend providing dry conditions and warmer temperatures. Chances of showers and thunderstorms return early next week with the approach of the next storm system. && .TSA Watches/Warnings/Advisories... OK...NONE. AR...NONE. && $$ AVIATION...23
AREA FORECAST DISCUSSION
NWS PORTLAND OR
910 AM PDT MON APR 18 2016 .SYNOPSIS...LITTLE CHANGE TODAY AND TUE...AS HIGH PRES OVER THE REGION WILL MAINTAIN A WARM AIR MASS. BUT...WILL SEE CHANGES LATER TUE AND TUE NIGHT AS ONSHORE FLOW USHERS COOLER AIR ACROSS THE REGION. MEANWHILE...LOW PRES OFFSHORE WILL DRAW CLOSER...BRINGING A CHANCE SHOWERS AND MAYBE A THUNDERSTORM TUE NIGHT AND WED. ANOTHER LOW PRES WILL APPROACH REGION LATER IN THE WEEK...WITH SEASONABLE UNSETTLED WEATHER THROUGH NEXT WEEKEND. && .UPDATE...ANOTHER WARM DAY IS IN STORE FOR TODAY AS HIGH PRESSURE REMAINS ALOFT AND A SURFACE THERMAL TROUGH MOVES OVER THE REGION. THE OFFSHORE WINDS WILL DECREASE THIS AFTERNOON WITH THE WINDS ON THE COAST BECOMING ON SHORE. SOME HIGH CLOUDS FROM AN UPPER LOW OFF OF CALIFORNIA IS STARTING TO STREAM OVER THE AREA TODAY. VISIBLE IMAGERY ALSO SHOWS AN AREA OF LOW CLOUDS OFFSHORE OF NORTHERN CALIFORNIA AND SOUTHERN OREGON. THESE CLOUDS ARE INITIALIZING WELL WITH THE HRRR MODEL WHICH FORECASTS THAT THIS STRATUS (AND POSSIBLY FOG) WILL MOVE NORTHWARD INTO THE CENTRAL OREGON COASTAL WATERS THIS AFTERNOON AND EVENING. THERE IS ALSO STRATUS WAY OFFSHORE TO THE NW THAT WILL APPROACH THE NORTHERN OREGON/SOUTHERN WASHINGTON WATERS TONIGHT. HAVE INCREASED SKY COVER FOR THIS AFTERNOON OVER THE WATERS...BUT HAVE KEPT SKIES MOSTLY CLEAR FOR THE COAST. WILL WATCH HOW THESE CLOUDS DEVELOP THIS AFTERNOON...AND MAY NEED TO MAKE FURTHER ADJUSTMENTS WITH THE AFTERNOON FORECAST PACKAGE. TJ PREVIOUS SHORT-TERM DISCUSSION...NOT MUCH CHANGE. HIGH PRES STILL OVER THE REGION...WITH LIGHT SOUTHERLY FLOW ALOFT. SINCE THE RIDGE AXIS IS NOW ANCHORED EAST OF THE CASCADES THIS AM... WILL SEE VARIABLE CIRRUS DRIFT ACROSS REGION TODAY. OFFSHORE FLOW HAS WEAKENED...SO NOT QUITE AS MUCH WIND TODAY AS SAW ON SUNDAY. BUT WITH CROSS-CASCADES GRADIENT STILL RUNNING AROUND 4.5 TO 5 MB OFFSHORE...WILL STILL HAVE BREEZY CONDITIONS CLOSE TO AND IN THE COLUMBIA GORGE WITH GUSTS 25 TO 35 MPH THERE. OTHERWISE...ANOTHER WARM DAY FOR MUCH OF THE REGION...WITH TEMPERATURES BACK INTO THE 80S. ONLY EXCEPTION WILL BE THE COASTAL AREAS...WHERE LIGHTER FLOW WILL ALLOW FOR AFTERNOON SEA BREEZE TO RESUME. THIS WILL KEEP AFTERNOON TEMPERATURES ALONG THE COAST IN THE UPPER 60S TO UPPER 70S. AGAIN...NOT MUCH CHANGE ON TUESDAY. BIG PLAYER IN THE WEATHER WILL BE THE UPPER LOW THAT NOW SITS WELL SW OF OREGON. MODELS HAVE BEEN CONSISTENT IN SLOWLY LIFTING THIS LOW OUT AND INTO OUR AREA TUE NIGHT AND WED. AS THIS LOW LIFTS NE...WILL SEE SURFACE RIDGE SHIFT NE AHEAD OF IT. THIS IS WHY EXPECT TO SEE INCREASING SWLY MARINE PUSH TUE NIGHT INTO WED. WHILE MODELS HAVE NOT BEEN ALL THAT IMPRESSIVE WITH LOW LEVEL HUMIDITY...BUT SEEMS MODELS MAY BE LATE ON CATCHING THIS AS WILL BE RATHER SHALLOW. WILL TREND TI INCREASING MARINE CLOUDS LATE TUE NIGHT ALONG THE COAST...AND INTO THE S WILLAMETTE VALLEY AS WELL. EXPECT WED TEMPERATURES TO BE MUCH COOLER WITH GENERALLY IN THE 60S...POSSIBLY LOWER 70S INLAND DEPENDING ON HOW MUCH THE MARINE LAYER CLOUDS BREAK UP IN THE AFTERNOON. THIS SYSTEM WILL WILL ALSO BRING INCREASING MID AND HIGH CLOUDS...AS WELL AS A CHANCE OF SHOWERS TUE NIGHT AND MAINLY ON WED. WHILE NORMALLY A BIT EARLY IN THE SEASON FOR THIS SORT OF THING...BEING ON THE HEELS OF A VERY WARM TUESDAY THERE IS A CHANCE OF SOME THUNDER AS THE SHORT WAVE LIFTS NORTH OVER THE REGION LATER TUE NIGHT AND WED. WILL KEEP SLIGHT CHANCE OF THUNDERSTORMS OVER MOST OF REGION LATE TUE NIGHT AND EARLY WED...THEN SHIFT THREAT EAST OF THE COAST RANGE BY WED AFTERNOON. ROCKEY .LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEDNESDAY NIGHT THROUGH SUNDAY. CONFIDENCE REMAINS RELATIVELY HIGH THAT A MORE PROGRESSIVE PATTERN WILL SET UP OVER THE REGION FOR THE SECOND HALF OF THE WEEK. A PASSING SHORTWAVE LATE WEDNESDAY NIGHT INTO EARLY THURSDAY MAY PROVIDE FOR SOME CONTINUED SHOWERS...BEFORE RAIN CHANCES CONTINUE WITH AN ARRIVING FRONT LATER THURSDAY. A DEEPER UPPER TROUGH THEN TAKES UP RESIDENCE NEAR THE REGION WITH EMBEDDED SHORTWAVES BRINGING PERIODS OF ENHANCED PRECIPITATION CHANCES. STILL SOME DIFFERENCES IN THE STRENGTH AND PLACEMENT OF THIS UPPER TROUGH...ALONG WITH THE TIMING OF VARIOUS SHORTWAVES...IN THE LATEST MODEL GUIDANCE...BUT OVERALL EXPECT MUCH MORE SEASONALLY TYPICAL TEMPERATURES ALONG WITH ABUNDANT CLOUD COVER AND RAIN CHANCES TO CONTINUE FOR THE FOR THE END OF THE WEEK THROUGH NEXT WEEKEND. SNOW LEVELS BEGIN ABOVE 7500 FEET THURSDAY BUT WILL GRADUALLY LOWER TO THE 4500 TO 5000 FOOT RANGE FOR NEXT WEEKEND. CULLEN && .AVIATION...VFR CONDITIONS EXPECTED THROUGH MONDAY UNDER VARIABLE HIGH CLOUDS. EAST WIND WILL CONTINUE TO EASE TODAY AS GRADIENTS RELAX AND THERMAL TROUGH DEVELOPS OVER THE WILLAMETTE VALLEY. HOWEVER SOME GUSTY WINDS AT KTTD TODAY. KPDX AND APPROACHES...VFR UNDER VARIABLE HIGH CLOUDS THROUGH MONDAY. LIGHT WINDS BUT SOME EAST WINDS CONTINUE EAST OF I205. LIGHT NW WINDS EXPECTED TO DEVELOP THIS EVENING. SCHNEIDER && .MARINE...QUIET MARINE CONDITIONS CONTINUE THROUGH LATE TUESDAY. WITH THERMAL TROUGH DEVELOPING INLAND WINDS WILL SHIFT TO THE NORTHWEST THIS EVENING. THE WEAK FRONT WHICH WILL MOVE INTO THE AREA ON WEDNESDAY IS LOOKING EVEN WEAKER NOW AND WILL LIKELY PROVIDE LITTLE CHANGE IN MARINE CONDITIONS. SOUTHERLY FLOW WITH THIS SYSTEM WILL BRING A THREAT OF THUNDERSTORMS TO THE WATERS. SOME GUSTY WINDS POSSIBLE WITH THESE STORMS. MORE ACTIVE WEATHER DEVELOPS AS SEVERAL WEAK FRONTS MOVE ACROSS THE WATERS MAINLY AFTER SATURDAY. SEAS 7 TO 8 FT EARLY THIS MORNING AS A LONG PERIOD WESTERLY SWELL WITH A PERIOD OF 14 TO 15 SECONDS MOVES THROUGH THE WATERS. SEAS SUBSIDE LATER TODAY TO AROUND 6 FT...AND COULD FALL TO AROUND 4 FT WEDNESDAY. SEAS POSSIBLY BUILD ABOVE 10 FT LATE IN THE WORK WEEK. COLUMBIA RIVER BAR REACHING 9 FT DURING THE EBB THIS AFTERNOON BUT WITH THE LONGER PERIOD SWELL DON`T EXPECT BREAKERS SO CONDITIONS WILL BE JUST BELOW SMALL CRAFT CRITERIA. MARINERS SHOULD USING CAUTION ON THE BAR. SCHNEIDER && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...NONE. && $$ INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/NWSPORTLAND WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
PLEASE SEE THE 00Z AVIATION FORECAST DISCUSSION BELOW.

AVIATION... VFR CONDITIONS ARE CURRENTLY IN PLACE ACROSS THE REGION. WITH CONTINUED COOLING IN THE MOIST LOW-LEVELS...CIGS WILL LOWER INTO MVFR BETWEEN 02Z-05Z. CONTINUED COOLING AND DECREASING OF WINDS SHOULD DROP CIGS INTO IFR BEGINNING 06Z-08Z. IFR CIGS WILL CONTINUE UNTIL LATE MORNING. WE COULD ALSO SEE SOME CONVECTION MOVE IN FROM THE NORTHWEST EARLY WEDNESDAY MORNING. WE/LL MAINTAIN PROB30 GROUPS AT ALL SITES FOR NOW...BUT IT APPEARS KAUS MIGHT STAND A BETTER CHANCE THAN OUR OTHER TAF SITES. CIGS WILL BE SLOW TO RISE TOMORROW...ESPECIALLY IF THUNDERSTORM ACTIVITY LEAVES LIGHT STRATIFORM RAIN IN IT/S WAKE. PREV DISCUSSION... /ISSUED 304 PM CDT TUE APR 19 2016/ SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)... AT 245PM...VISIBLE SATELLITE SHOWED CONVECTIVE INITIATION BEGINNING OFF THE MEXICAN MOUNTAINS AND UP THROUGH THE BIG BEND AREA. FARTHER EAST INTO OUR CWA...STRATUS WAS JUST BEGINNING TO DETERIORATE WHICH HAS BEEN LIMITING THE CONVECTIVE POTENTIAL. HOWEVER STILL WITH A FEW HOURS OF HEATING LEFT IN THE DAY...A SLIGHT CHANCE OF STRONG TO SEVERE THUNDERSTORMS COULD BE POSSIBLE FOR THE WESTERN PLATEAU COUNTIES...LIKE VAL VERDE. LOW LEVEL LAPSE RATES ON THE PLATEAU ARE SUB 6 DEG/KM PER THE RAP HOWEVER AND WITH SUPERCELL STORM MOTION VECTORS WEST OF THE RIO GRANDE PARALLEL TO THE RIVER AND APPRECIABLE CONVECTION INHIBITION FARTHER EAST...CONFIDENCE IS LOW ON STORMS IN OUR CWA THIS EVENING. HOWEVER...SHOULD SOME CELLS MAKE IT INTO THE CWA...ENOUGH INSTABILITY MAY BE GENERATED BY LATE THIS AFTERNOON TO WARRANT A MARGINALLY SEVERE HAIL THREAT. THIS CONVECTION FARTHER WEST AND NORTH IS BEING PRETTY WELL HANDLED IN THE HI RESOLUTION MODELS THIS AFTERNOON AND THEY ARE INDICATING CONGLOMERATING INTO A QUASI LINEAR SYSTEM OR BROKEN LINE OF MULTI CELLS PUSHING SOUTHEAST INTO THE NORTHERN CWA BY EARLY TOMORROW MORNING. MORE SPECIFICALLY THE 4AM-10AM TIME FRAME. THE LINE SHOULD BE ABLE TO PASS THROUGH AT A DECENT SPEED...ENOUGH TO TYPICALLY NOT BE MUCH OF A CONCERN FOR FLASH FLOODING. IN FACT...PWATS AT 12Z ARE ONLY IN THE 1.4 INCH RANGE IN THE AUSTIN AREA. SO IT LOOKS LIKE QPF WISE...THAT GENERALLY AROUND AN INCH OR SO WILL RESULT FROM THE PASSAGE OF THIS LINE. HOWEVER...WHILE ISOLATED...THERE MAY BE SOME SPOTS THAT GET 3 INCHES OR SO WHICH WOULD BE QUITE PROBLEMATIC FOR COUNTIES IN THE EAST WHICH RECEIVED OVER 8 INCHES OF RAIN FROM YESTERDAY. THEREFORE THE DECISION TO MAINTAIN A FFA EAST OF I35 WAS MADE FOR THOSE HIGHLY VULNERABLE ANTECEDENT COUNTIES SPECIFICALLY...WHILE OTHER COUNTIES SHOULD BE ABLE TO HANDLE THE RAINFALL. LONG TERM (THURSDAY THROUGH TUESDAY)... THE BIG UPPER LOW OVER THE ROCKIES RESPONSIBLE FOR ALL OF OUR RAIN ACTIVITY LATELY WILL BEGIN TO FINALLY SHIFT EASTWARD THURSDAY AND PROGRESS ACROSS THE CENTRAL UNITED STATES. THIS SHOULD QUICKLY TRANSITION THE UPPER LEVEL PATTERN FOR THE REGION INTO A NORTHWEST FLOW SITUATION. ANOTHER SHORTWAVE WILL PASS INTO THE RED RIVER VALLEY AND INTO THE ARKLATEX THURSDAY AS WELL. THIS WILL BRING ANOTHER SHOT AT SHOWERS AND STORMS THURSDAY AFTERNOON AND EVENING FAVORING THE NORTHERN AND EASTERN ZONES YET AGAIN. A COLD FRONT WILL PUSH THROUGH THE AREA LATE THURSDAY NIGHT BEHIND THE QPF REPLACING THE AIR MASS WITH MUCH DRIER AIR FRIDAY. A BRIEF DRY PERIOD WILL EXIST THROUGH SATURDAY AFTERNOON WHEN A WEAK SHORTWAVE COMES ACROSS THE STATE THIS WEEKEND WITH THE NEXT POP OPPORTUNITY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 66 79 65 79 60 / 50 60 30 40 20 AUSTIN BERGSTROM INTL AIRPORT 67 79 64 79 59 / 50 60 30 40 20 NEW BRAUNFELS MUNI AIRPORT 67 80 64 80 61 / 50 60 30 40 30 BURNET MUNI AIRPORT 63 78 62 78 57 / 60 50 30 40 20 DEL RIO INTL AIRPORT 65 83 66 85 62 / 40 20 20 20 20 GEORGETOWN MUNI AIRPORT 65 78 63 78 58 / 60 60 30 40 20 HONDO MUNI AIRPORT 65 82 65 84 61 / 40 40 30 40 20 SAN MARCOS MUNI AIRPORT 66 79 65 79 60 / 50 60 30 40 30 LA GRANGE - FAYETTE REGIONAL 69 78 65 79 61 / 50 60 30 50 30 SAN ANTONIO INTL AIRPORT 67 81 66 81 63 / 50 50 30 40 20 STINSON MUNI AIRPORT 68 82 67 82 63 / 50 50 30 40 20 && .EWX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR THE FOLLOWING COUNTIES: BASTROP...CALDWELL...DE WITT...FAYETTE...GONZALES... LAVACA...LEE. && $$ MESOSCALE/AVIATION...24 SYNOPTIC/GRIDS...OAKS PUBLIC SERVICE/DATA COLLECTION...TREADWAY
PLEASE SEE THE 00Z AVIATION FORECAST DISCUSSION BELOW.

&& .AVIATION... VFR CONDITIONS ARE CURRENTLY IN PLACE ACROSS THE REGION. WITH CONTINUED COOLING IN THE MOIST LOW-LEVELS...CIGS WILL LOWER INTO MVFR BETWEEN 02Z-05Z. CONTINUED COOLING AND DECREASING OF WINDS SHOULD DROP CIGS INTO IFR BEGINNING 06Z-08Z. IFR CIGS WILL CONTINUE UNTIL LATE MORNING. WE COULD ALSO SEE SOME CONVECTION MOVE IN FROM THE NORTHWEST EARLY WEDNESDAY MORNING. WE/LL MAINTAIN PROB30 GROUPS AT ALL SITES FOR NOW...BUT IT APPEARS KAUS MIGHT STAND A BETTER CHANCE THAN OUR OTHER TAF SITES. CIGS WILL BE SLOW TO RISE TOMORROW...ESPECIALLY IF THUNDERSTORM ACTIVITY LEAVES LIGHT STRATIFORM RAIN IN IT/S WAKE. && .PREV DISCUSSION... /ISSUED 304 PM CDT TUE APR 19 2016/ SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)... AT 245PM...VISIBLE SATELLITE SHOWED CONVECTIVE INITIATION BEGINNING OFF THE MEXICAN MOUNTAINS AND UP THROUGH THE BIG BEND AREA. FARTHER EAST INTO OUR CWA...STRATUS WAS JUST BEGINNING TO DETERIORATE WHICH HAS BEEN LIMITING THE CONVECTIVE POTENTIAL. HOWEVER STILL WITH A FEW HOURS OF HEATING LEFT IN THE DAY...A SLIGHT CHANCE OF STRONG TO SEVERE THUNDERSTORMS COULD BE POSSIBLE FOR THE WESTERN PLATEAU COUNTIES...LIKE VAL VERDE. LOW LEVEL LAPSE RATES ON THE PLATEAU ARE SUB 6 DEG/KM PER THE RAP HOWEVER AND WITH SUPERCELL STORM MOTION VECTORS WEST OF THE RIO GRANDE PARALLEL TO THE RIVER AND APPRECIABLE CONVECTION INHIBITION FARTHER EAST...CONFIDENCE IS LOW ON STORMS IN OUR CWA THIS EVENING. HOWEVER...SHOULD SOME CELLS MAKE IT INTO THE CWA...ENOUGH INSTABILITY MAY BE GENERATED BY LATE THIS AFTERNOON TO WARRANT A MARGINALLY SEVERE HAIL THREAT. THIS CONVECTION FARTHER WEST AND NORTH IS BEING PRETTY WELL HANDLED IN THE HI RESOLUTION MODELS THIS AFTERNOON AND THEY ARE INDICATING CONGLOMERATING INTO A QUASI LINEAR SYSTEM OR BROKEN LINE OF MULTI CELLS PUSHING SOUTHEAST INTO THE NORTHERN CWA BY EARLY TOMORROW MORNING. MORE SPECIFICALLY THE 4AM-10AM TIME FRAME. THE LINE SHOULD BE ABLE TO PASS THROUGH AT A DECENT SPEED...ENOUGH TO TYPICALLY NOT BE MUCH OF A CONCERN FOR FLASH FLOODING. IN FACT...PWATS AT 12Z ARE ONLY IN THE 1.4 INCH RANGE IN THE AUSTIN AREA. SO IT LOOKS LIKE QPF WISE...THAT GENERALLY AROUND AN INCH OR SO WILL RESULT FROM THE PASSAGE OF THIS LINE. HOWEVER...WHILE ISOLATED...THERE MAY BE SOME SPOTS THAT GET 3 INCHES OR SO WHICH WOULD BE QUITE PROBLEMATIC FOR COUNTIES IN THE EAST WHICH RECEIVED OVER 8 INCHES OF RAIN FROM YESTERDAY. THEREFORE THE DECISION TO MAINTAIN A FFA EAST OF I35 WAS MADE FOR THOSE HIGHLY VULNERABLE ANTECEDENT COUNTIES SPECIFICALLY...WHILE OTHER COUNTIES SHOULD BE ABLE TO HANDLE THE RAINFALL. LONG TERM (THURSDAY THROUGH TUESDAY)... THE BIG UPPER LOW OVER THE ROCKIES RESPONSIBLE FOR ALL OF OUR RAIN ACTIVITY LATELY WILL BEGIN TO FINALLY SHIFT EASTWARD THURSDAY AND PROGRESS ACROSS THE CENTRAL UNITED STATES. THIS SHOULD QUICKLY TRANSITION THE UPPER LEVEL PATTERN FOR THE REGION INTO A NORTHWEST FLOW SITUATION. ANOTHER SHORTWAVE WILL PASS INTO THE RED RIVER VALLEY AND INTO THE ARKLATEX THURSDAY AS WELL. THIS WILL BRING ANOTHER SHOT AT SHOWERS AND STORMS THURSDAY AFTERNOON AND EVENING FAVORING THE NORTHERN AND EASTERN ZONES YET AGAIN. A COLD FRONT WILL PUSH THROUGH THE AREA LATE THURSDAY NIGHT BEHIND THE QPF REPLACING THE AIR MASS WITH MUCH DRIER AIR FRIDAY. A BRIEF DRY PERIOD WILL EXIST THROUGH SATURDAY AFTERNOON WHEN A WEAK SHORTWAVE COMES ACROSS THE STATE THIS WEEKEND WITH THE NEXT POP OPPORTUNITY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 66 79 65 79 60 / 50 60 30 40 20 AUSTIN BERGSTROM INTL AIRPORT 66 79 64 79 59 / 50 60 30 40 20 NEW BRAUNFELS MUNI AIRPORT 66 80 64 80 61 / 40 60 30 40 30 BURNET MUNI AIRPORT 63 78 62 78 57 / 50 40 30 40 20 DEL RIO INTL AIRPORT 65 83 66 85 62 / 40 30 20 20 20 GEORGETOWN MUNI AIRPORT 65 78 63 78 58 / 50 60 30 40 20 HONDO MUNI AIRPORT 65 82 65 84 61 / 40 30 30 30 20 SAN MARCOS MUNI AIRPORT 66 79 65 79 60 / 50 60 30 40 30 LA GRANGE - FAYETTE REGIONAL 68 78 65 79 61 / 50 60 30 50 30 SAN ANTONIO INTL AIRPORT 66 81 66 81 63 / 40 50 30 40 20 STINSON MUNI AIRPORT 68 82 67 82 63 / 40 40 30 40 20 && .EWX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR THE FOLLOWING COUNTIES: BASTROP...CALDWELL...DE WITT...FAYETTE...GONZALES... LAVACA...LEE. && $$ MESOSCALE/AVIATION...24 SYNOPTIC/GRIDS...OAKS PUBLIC SERVICE/DATA COLLECTION...TREADWAY
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
651 PM CDT TUE APR 19 2016 .AVIATION... IN SIMILAR FASHION TO THIS MORNING...VFR CONDITIONS ARE LIKELY TO CRATER TO IFR AT PVW AND LBB AFTER MIDNIGHT AS THE LOWER ATMOSPHERE REMAINS VERY MOIST. COULD SEE DENSE FOG ALSO DEVELOP THOUGH THIS IS LESS LIKELY COMPARED TO JUST VERY LOW STRATUS. CONFIDENCE IN IFR AT CDS IS LESS CERTAIN AS SOME MODELS ARE RELUCTANT TO REDEVELOP LOW CLOUDS...BUT HAVE HINTED AT THIS SCENARIO WITH A SCATTERED LOW LAYER. SHOULD SEE VFR RETURN TO LBB AND PVW BY THE AFTN AT WHICH POINT A REPEAT OF AFTERNOON TS ARE POSSIBLE SOUTH OF AN UPPER LOW...MAINLY N OF LBB. && .PREV DISCUSSION... /ISSUED 318 PM CDT TUE APR 19 2016/ SHORT TERM... PRECIP CHANCES WILL CONTINUE TO BE THE FOCUS TONIGHT AND AGAIN WEDNESDAY. ONGOING SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS BEGINNING TO MARCH EWD ACROSS THE NRN HALF OF THE FCST AREA AT A PRETTY GOOD CLIP. THE SOURCE REGION FOR CONVECTIVE REDEVELOPMENT THAT HAD BEEN ANCHORED IN ERN NM IS SHIFTING TO THE WRN SOUTH PLAINS. THIS ADJUSTMENT OCCURRING IN RESPONSE TO THE MAIN UPPER TROUGH OVER NRN NM SHOWING EWD MOVEMENT PER WATER VAPOR IMAGERY THE LAST COUPLE HOURS. TROUGH AXIS SHOULD SHIFT TO THE EAST OF THE FCST AREA AROUND 06Z WITH HIGH CHANCE TO LIKELY POPS ERN HALF OF THE FCST AREA APPROPRIATE UNTIL THEN. COULD ALSO SEE A SHIFT SWD WITH THE CONVECTION AS OUTFLOW INTERACTS WITH LOW LEVEL MOISTURE SRN SOUTH AND ROLLING PLAINS PER HRRR OUTPUT. FOCUS THEN SHIFTS TO PRECIP CHANCE WEDNESDAY. APPEARS A DECENTLY DEFINED DRYLINE WILL SHIFT INTO THE WRN ZONES DURING THE AFTN. LOW LEVEL MOISTURE TO REMAIN IN PLACE TO ITS EAST WITH SFC DEW POINT TEMPS UPPER 40S-LOWER 50S. NOT MUCH UPPER SUPPORT EVIDENT WITH A SHORT WAVE TROUGH PROGGED TO SEWD THROUGH THE MEAN FLOW FROM SRN COLORADO TWD THE PANHANDLE. WEAKLY FORCED CONVECTIVE INITIATION POSSIBLE LATE AFTN JUST EAST OF THE DRYLINE GENERALLY ALONG I-27. ONLY OTHER ISSUE IS CHANCE FOR FOG AROUND SUNRISE. COOL...MOIST AIR MASS WITH UPSLOPE EASTERLY LOW LEVEL FLOW POINT TO THE POSSIBILITY. NO CONSENSUS FROM GUIDANCE ATTM. WILL KEEP MENTION OUT FOR NOW AND LET NEXT SHIFT REEVALUATE. LONG TERM... A SECONDARY COLD FRONT WILL PUSH THROUGH TOMORROW NIGHT AS A SHORT WAVE ROTATES AROUND THE BACKSIDE OF THE MUCH LARGER UPPER LEVEL LOW ACROSS THE MIDWEST. WITH PLENTY OF MOISTURE IN PLACE AS WELL AS LIFT FROM THE SHORTWAVE A COMPLEX OF SHOWERS AND THUNDERSTORMS WILL BE HIGHLY POSSIBLE ACROSS THE EASTERN TX PANHANDLE AND ROLLING PLAINS. WHILE SOME HEAVY RAIN WILL BE POSSIBLE AS PWATS WILL BE OVER 1 INCH THE COMPLEX SHOULD MOVE QUICK ENOUGH TO HELP MITIGATE FLOODING CONCERNS. WINDS WILL REMAIN OUT OF THE NORTHEAST INTO LATE THURSDAY NIGHT WHICH WILL HELP KEEP TEMPS INTO THE LOW 70S. WINDS WILL TURN BACK TO THE SOUTH/SOUTHEAST BY EARLY FRIDAY AFTERNOON AS A LEE TROF DEVELOPS. THIS...IN ADDITION TO AN UPPER RIDGE MOVING OVER THE REGION...WILL ALLOW TEMPS TO WARM BACK TO NEAR AVERAGE FRIDAY. TEMPS WILL CONTINUE TO WARM TO SEVERAL DEGREES ABOVE AVERAGE BY SUNDAY AS WINDS WILL CONTINUOUSLY STAY OUT OF THE SOUTH TO SOUTHWEST. THE LEE TROF WILL PUSH SOUTHWARD STARTING LATE SUNDAY MORNING ALLOWING A DRYLINE TO PUSH EASTWARD FROM NM. A SMALL CHANCE EXISTS FOR ISOLATED THUNDERSTORMS ALONG THE DRYLINE...MOSTLY OVER THE ROLLING PLAINS...SUNDAY BUT WILL BE DEPENDENT ON THE TIMING OF A PASSING SHORTWAVE. WINDS WILL BE FAIRLY BREEZY...SPECIFICALLY ACROSS OUR NORTHWESTERN COUNTIES...BEHIND THE DRYLINE AS THE MID TO LOWER LEVELS DRY AND THERMAL PROFILES BECOME SUPER ADIABATIC. CONDITIONS BEYOND LATE SUNDAY BECOME QUESTIONABLE AS MODELS BEGIN TO DIVERGE WITH THE UPPER LEVEL PATTERN. THE ECMWF BRINGS AN UPPER LEVEL LOW CLOSE TO THE REGION BY MONDAY AFTERNOON/EVENING WHICH WOULD ALLOW WINDS TO KEEP BLOWING WHILE THE GFS TAKES A MORE PACIFIST ROLE BY KEEPING FLOW MOSTLY ZONAL AND DELAYING THE APPROACH OF THE LOW UNTIL EARLY WEDNESDAY. EITHER WAY THE FORECAST LOOKS TO REMAIN DRY. && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 93
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
341 PM CDT MON APR 18 2016 .SHORT TERM (TONIGHT AND TUESDAY)...COMPLEX SCENARIO PLAYING OUT ACROSS SOUTH TEXAS AT THIS TIME. COLD OUTFLOW FROM DYING CONVECTION FROM THE UPPER TEXAS COAST HAS SURGED THROUGH THE COASTAL WATERS AND THE COASTAL BEND...WHICH ONLY THE RAP MODEL PICKED UP ON IN THE LAST COUPLE OF HOURS. AIR MASS HAS BECOME UNSTABLE TO THE SOUTH OF THE OUTFLOW BOUNDARY WITH MIXED LAYER CAPE VALUES BETWEEN 1500-2000 J/KG AND 35-40 KNOTS OF SHEAR IN THE 0-6 KM LAYER. STORMS FORMING OVER THE BRUSH COUNTRY ARE EXPECTED TO CONTINUE GROWING UPSCALE AS THEY MOVE EAST-SOUTHEAST. SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE BRUSH COUNTRY TO JIM WELLS COUNTY UNTIL 11 PM THIS EVENING. HOW ALL OF THIS AFFECTS THE HEAVY RAIN/FLASH FLOOD POTENTIAL IS UNCERTAIN ESPECIALLY FOR THE VICTORIA CROSSROADS REGION WHERE AIR MASS HAS STABILIZED BEHIND THE OUTFLOW BOUNDARY. THERE IS A POSSIBILITY THAT ACTIVITY FORMING TO THE WEST COULD MOVE OVER THE OUTFLOW BOUNDARY AND REMAIN ORGANIZED BUT IN AN ELEVATED NATURE. EXPANDED THE FLASH FLOOD WATCH EARLIER TO INCLUDE THE WESTERN BRUSH COUNTRY. FOR NOW...WILL MAINTAIN FLASH FLOOD WATCH FOR THE REST OF THE AREA FOR TONIGHT BUT THIS WILL LIKELY NEED MODIFICATION LATER THIS EVENING. THE FORECAST FOR TUESDAY WILL BE DEPENDENT ON WHERE OUTFLOW BOUNDARY/MOISTURE AXIS WILL RESIDE BUT WILL GO ALONG WITH NAM/GFS SHOWING HIGHER MOISTURE AXIS OVER THE COASTAL PLAINS INTO THE COASTAL WATERS TO SHOW WHERE HIGHER POPS WILL BE FOR TUESDAY. && .MARINE (TONIGHT)...MODERATE TO STRONG NORTHEAST WINDS ASSOCIATED WITH OUTFLOW FROM DIMINISHING CONVECTION OFF THE UPPER TEXAS COAST WILL CONTINUE THROUGH THE EVENING. THIS WILL BE ASSISTED BY AN AREA OF LOW PRESSURE THAT FORMED TO THE NORTH OF THE CONVECTIVE COMPLEX THAT HAS MOVED WELL OFFSHORE OF THE LOWER TEXAS COAST. SCA IS IN EFFECT FOR THE BAYS UNTIL 04Z...THOUGH 07Z FOR THE NEAR SHORE WATERS AND 12Z FOR THE OFFSHORE WATERS. SEAS HAVE BUILT TO 8 FEET AT THE OFFSHORE BUOYS AND MAY GO TO 9-10 FEET BEFORE SUBSIDING. EXPECT STRONG CONVECTION WILL MOVE THROUGH THE WATERS TONIGHT. && .TIDES...TIDES AND BAY LEVELS HAVE INCREASED SLIGHTLY DUE TO THE STRONG NORTHEAST WINDS BEHIND THE OUTFLOW. TIDES ARE 2-2.25 FEET ABOVE PREDICTED BUT THIS WILL STILL REMAIN IN THE COASTAL FLOOD ADVISORY CRITERIA RANGE. THE ADVISORY WILL REMAIN IN EFFECT THROUGH TUESDAY MORNING AS WELL AS THE HIGH RISK FOR RIP CURRENTS. && .LONG TERM (TUESDAY NIGHT THROUGH MONDAY)...DETERMINISTIC GFS/ECMWF PREDICT THE EARLY STAGES OF THE BREAKDOWN OF THE OMGEGA BLOCK AT THE BEGINNING OF THE PERIOD TO A PROGRESSIVE UPPER TROUGH MOVG ACRS THE MIDWEST THURSDAY. THUS...A DECREASE IN SYNOPTIC SCALE LIFT EXPECTED OVER THE CWA/MSA TUESDAY NIGHT THROUGH THURSDAY. YET...CONCUR WITH THE GFS DETERMINISTIC WHICH MAINTAINS COPIOUS MSTR (ORIGINATING OVER THE WRN/SWRN GULF OF MEXICO PER SPORT CIRA TOTAL LPW) OVER THE ERN CWA/MSA THROUGH THURSDAY. THUS WL MAINTAIN SCT CONVECTION OVER THE CWA/MSA TUESDAY NIGHT THROUGH THURSDAY. PATCHY FOG MAY OCCUR EARLY WEDNESDAY/THURSDAY MORNINGS PER SREF PROBABILITIES. PER THE WAVEWATCH...SWELL HEIGHTS/PERIODS MAY MAINTAIN MODERATE/HIGH RISK FOR RIP CURRENTS. FRIDAY/SATURDAY...IN RESPONSE TO THE PROGRESSIVE UPPER PATTERN...ANTICIPATE THAT INCREASING SUBSIDENCE/DRYING WL PRECLUDE SIGNIFICANT CONVECTION BY LATE FRIDAY. SATURDAY NIGHT/ SUNDAY...THE GFS ENSEMBLE MEAN SUGGESTS THAT ANOTHER UPPER SYSTEM WL PROVIDE SYNOPTIC SCALE LIFT OVER THE CWA/MSA LATE SATURDAY THROUGH MONDAY. GFS DETERMINISTIC INCREASES MSTR AGAIN IN ADVANCE OF THIS SYSTEM. WL ONLY FCST ISOLD CONVECTION SUNDAY/MONDAY. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 72 82 72 82 71 / 80 50 40 50 30 VICTORIA 69 81 70 82 68 / 70 50 40 50 30 LAREDO 70 88 70 88 70 / 70 30 40 40 30 ALICE 70 85 71 85 69 / 80 40 40 50 30 ROCKPORT 73 81 72 82 71 / 80 60 40 50 30 COTULLA 67 85 69 86 68 / 70 30 40 40 30 KINGSVILLE 71 84 71 84 70 / 80 50 40 50 30 NAVY CORPUS 73 81 72 79 72 / 80 50 40 50 30 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR THE FOLLOWING ZONES: ARANSAS...BEE...CALHOUN...DUVAL...GOLIAD...JIM WELLS...KLEBERG...LIVE OAK...MCMULLEN...NUECES...REFUGIO... SAN PATRICIO...VICTORIA. HIGH RIP CURRENT RISK THROUGH TUESDAY MORNING FOR THE FOLLOWING ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES. COASTAL FLOOD ADVISORY UNTIL 7 AM CDT TUESDAY FOR THE FOLLOWING ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES...SAN PATRICIO. FLASH FLOOD WATCH UNTIL 1 AM CDT TUESDAY FOR THE FOLLOWING ZONES: LA SALLE...WEBB. GM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY FOR THE FOLLOWING ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 11 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT OCONNOR. SMALL CRAFT ADVISORY UNTIL 2 AM CDT TUESDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM. && $$ TMT/89...SHORT TERM WC/87...LONG TERM
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
1231 AM CDT MON APR 18 2016 .DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. && .AVIATION...SFC OBS AROUND DEEP SOUTH TEXAS SHOWS MAINLY MVFR CIGS WITH IFR AT TIMES. SATELLITE AND RADAR TRENDS REVEAL SHOWERS AND ISOLD TSTORMS DEVELOPING TO OUR SOUTH AND MOVING NORTHEAST. SHORT RANGE MODELS INDICATE AND CONTINUANCE OF THIS TREND THROUGH THE REST OF THE NIGHT. THE HRRR TAKES THE PRECIPITATION OFFSHORE BY 11Z WITH THE REST OF THE MORNING REMAINING DRY. WILL FOLLOW THIS TREND WITH SHRA THROUGH 10Z. SE WINDS PICK UP LATER THIS MORNING WITH GUSTS OVER 20 KNOTS POSSIBLE. FAVORABLE CONDS FOR TSTORMS LATER IN THE DAY FOR THE TAF SITES LASTING THROUGH MID EVENING. && .PREV DISCUSSION... /ISSUED 625 PM CDT SUN APR 17 2016/ DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. AVIATION...MVFR CIGS...DIPPING INTO IFR AT TIMES...WILL PREVAIL ALONG WITH MODERATE SOUTHEAST WINDS. HRRR SUGGESTS THAT ISOLATED SHOWERS AND TSTMS WILL DEVELOP SOUTH OF THE RIVER AND MOVE INTO THE CWA OVERNIGHT...BUT NOT SEEING DEFINITIVE COVERAGE AT THE TAF SITES. TAFS WILL THEREFORE REMAIN LOW KEY ON CONVECTIVE MENTION FOR NOW. PREV DISCUSSION... /ISSUED 255 PM CDT SUN APR 17 2016/ SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...UPPER LEVEL CENTERED OVER CO WILL MEANDER OVER THE AREA THROUGH THE SHORT TERM WITH SW FLOW INCREASING UPPER LEVEL DIVERGENCE OVER SOUTH CENTRAL TEXAS. SE FLOW AT 850MB CONTINUE TO FEED DEEP GULF MOISTURE INTO THE AREA. THE 12Z PRECIPITABLE WATER VALUES AT KBRO SHOWS AN INCREASE TO 1.5 INCHES IN THE LOWER LEVELS OF THE COLUMN WHILE STRONG INVERSION IS IN PLACE ABV 850MB. ISOLATED TO SCATTERED SHOWERS WILL DEVELOP THIS AFTERNOON NEAR THE COAST WITH A NORTH MOVEMENT PRODUCING BRIEF RAIN SHOWERS. BKN TO OVC CLOUD DECK WITH A FEW BREAKS THIS AFTERNOON WILL ALLOW FOR MORE SUNSHINE TO REACH THE SURFACE AND WARM UP TEMPERATURES INTO THE UPPER 80S TODAY AND NEAR 90 OUT WEST WHERE THERE WILL BE WITH LESS CLOUDS. MOISTURE CONTENT WILL REMAIN HIGH THROUGH THE NIGHT WITH A SOUTHEASTERLY FLOW IN PLACE. AS THE INVERSION STRENGTHENS OVERNIGHT WITH THE ABUNDANT MOISTURE IN PLACE...THIS WILL ALLOW FOR HAZE CONDITIONS OVERNIGHT AS IT REMAINS TRAP UNDER THE INVERSION. CEILINGS WILL REMAIN IN THE LOWER END AS WELL WITH THE POTENTIAL FOR A FEW SHOWERS AND THUNDERSTORMS ACROSS THE CWA. LOW TEMPERATURES OVERNIGHT WILL REMAIN IN THE LOW TO MID 70S. MONDAY AND MONDAY NIGHT...THE POTENTIAL FOR RAIN WILL CONTINUE WITH SEVERAL IMPULSES TRAVELING ACROSS THE PERIPHERY OF THE LOW. A CLUSTER OF CONVECTION WILL DEVELOP OVER S CENTRAL TEXAS AND GRADUALLY MOVE EAST TO SOUTHEAST MON INTO TUE AS THE BOUNDARY FRONT WITH THIS SYSTEM SLOWLY ADVANCES E. THIS COULD TRANSITION INTO A QUASI-LINEAR CLUSTER OF STORMS AS IT MAKES ITS WAY ACROSS THE REGION. SIGNIFICANT RAINFALL IS EXPECTED IN CENTRAL TEXAS BUT THIS CLUSTER COULD PRODUCE VERY HEAVY DOWNPOURS AS IT MOVES THROUGH THE CWA MONDAY INTO TUE. RAINFALL AMOUNTS WILL RANGE BETWEEN HALF INCH TO 2 IN WITH HIGHER AMOUNTS WITH STRONGER STORMS. COULD ALSO EXPECT GUSTY WINDS AND FREQUENT LIGHTNING. THE TEMPS WILL STRUGGLE TO REACH THE 90S WITH BKN TO OVC CLOUD DECK EXPECTED THROUGH MUCH OF THE PERIOD. LOW TEMPS WILL REMAIN IN THE 70S BOTH NIGHTS. LONG TERM /TUESDAY THROUGH SUNDAY/...AS THE UPPER LOW FINALLY LIFTS NORTHEAST AND BEGINS TO FILL TUESDAY THROUGH WEDNESDAY THE MID TO UPPER LEVEL FLOW ACROSS THE CONUS WILL TRANSITION INTO A MORE PROGRESSIVE WEST TO EAST FLOW. 12Z MODEL PACKAGE ARE IN GOOD CONSISTENCY WITH THIS TREND BUT WITH A PROGRESSIVE TYPE FLOW THE TIMING OF POTENTIAL EMBEDDED SMALLER SHORTWAVES AND RIDGES BECOME AN ISSUE. THE OVERALL TREND FOR DEEP SOUTH TEXAS IS FOR A DECENT CHANCE OF RAIN TUESDAY WITH TEXAS STILL BE BEING INFLUENCE BY THE UPPER LOW AS IT SLOWLY LIFTS NORTHEAST. AS THE MID LEVEL FLOW BECOMES MORE NW-W-SW THE REMAINDER OF THE WEEK A QUICK PROGRESSION OF SHORTWAVE TROUGHS AND RIDGES PASS ACROSS NORTH MEXICO AND SOUTH TEXAS. MODELS ARE CURRENTLY PIN POINTS TROUGHS IMPACTING OUR CWA THURSDAY AND SATURDAY WITH SLIGHTLY DEEPER MOISTURE ON THOSE DAYS. A WEAK FRONTAL TROUGH IS ALSO INDICATED BY BOTH THE GFS AND ECMWF TO MOVE THROUGH ON FRIDAY AS A STRONGER UPPER TROUGH SWINGS THROUGH THE OHIO VALLEY. ALL THESE FEATURES KEEP SOME CHANCE OF RAIN ACROSS THE FORECAST REGION WHILE MAINTAINING SEASONAL TEMPERATURES. LATEST FORECAST MAINTAINS THE GENERAL TREND FROM THE PREVIOUS FORECAST WITH ONLY MINOR CHANGES. MARINE...TODAY THROUGH MONDAY...SFC TROUGH DEVELOPING ACROSS CENTRAL TEXAS WILL HELP RAMP UP SOUTHERLY WINDS ACROSS MARINE AREAS DURING THE NEXT 36 HOURS. WINDS ACROSS THE MARINE AREAS WILL REACH 15 TO 20 KNOTS TODAY AND AROUND 20 KNOTS TONIGHT. THIS WILL INCREASE SEAS TO 5 TO 7 FEET OVERNIGHT...AND WILL CONTINUE INTO THE DAY MONDAY. ADVISORIES ARE LIKELY TONIGHT INTO MONDAY...AND MAY BE NEEDED EARLIER THIS AFTERNOON IF WINDS RAMP UP FASTER. TUESDAY THROUGH FRIDAY...A SERIES OF WEAK MID LEVEL LOW PRESSURE TROUGHS AND RIDGES TO MOVE ACROSS NORTHERN PORTIONS OF THE GULF OF MEXICO TUESDAY THROUGH THE END OF THE WEEK. SURFACE CONDITIONS REMAIN BENIGN WITH A MODERATE SOUTHEAST FLOW TUESDAY THROUGH THURSDAY BECOMING BRIEFLY EAST TO NORTHEAST THURSDAY NIGHT INTO EARLY FRIDAY IN WAKE OF A WEAK FRONTAL BOUNDARY. SEAS CONTINUE TO GRADUALLY SUBSIDE TUESDAY WITH LOW TO MODERATE SEAS THE REST OF THE WEEK. OCCASIONAL UNSETTLED WEATHER CONDITIONS ARE ANTICIPATED EACH DAY WITH A DAILY CHANCE OF A SHOWER OR THUNDERSTORM ANYTIME. BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM CDT MONDAY FOR GMZ130- 132-135. SMALL CRAFT ADVISORY UNTIL 10 AM CDT MONDAY FOR GMZ150-155-170- 175. $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 55
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1156 PM CDT SUN APR 17 2016 .AVIATION... VFR CONDITIONS IN PLACE AT ALL THREE TAF SITES AND PRECIPITATION HAS DISSIPATED ACROSS THE REGION. UNCERTAINTY REMAINS HIGH ON THE DEVELOPMENT OF MVFR TO IFR CEILINGS AT KLBB AND KPVW LATER TONIGHT INTO MONDAY MORNING WHILE KCDS SHOULD REMAIN VFR. HAVE KEPT PREVIOUS TIMING IN PLACE FOR KLBB AND KPVW FOR MVFR CEILINGS AND WHEN THEY SHOULD DISSIPATE. RETURN TO VFR CONDITIONS IS EXPECTED FOR MONDAY AFTERNOON. JORDAN && .PREV DISCUSSION... /ISSUED 635 PM CDT SUN APR 17 2016/ AVIATION... VFR CONDITIONS IN PLACE AT KLBB AND KPVW...KCDS IS NOW MVFR AFTER SPENDING THE BETTER PART OF THE DAY IFR. SHOWERS WEST OF KLBB AND KPVW SHOULD REMAIN OUT SIDE THE RANGE FOR VICINITY OR OVER THE TERMINALS THEMSELVES. MOVEMENT AND COVERAGE WILL PRECLUDE INCLUDING ANYTHING GIN THE TAFS AT THIS TIME BUT WILL WATCH TO SEE IF A STRAY SHOWER COULD IMPACT KPVW OR KLBB. EXPECT ALL SITES TO RETURN TO MVFR CONDITIONS AFTER SUNSET WITH A FEW PERIODS OF IFR BUT CONFIDENCE IN TIMING OF IFR IS TOO LOW TO INCLUDE CURRENTLY. COMPUTER MODELS ARE ALSO KEEPING LOW CONFIDENCE IN CEILING AND VISIBILITY RANGES BECAUSE OF MAJOR DIFFERENCES... ONE MODEL SHOWING VLIFR AT KPVW AND KLBB WITH THE OTHER SHOWING MVFR OVERNIGHT. REGARDLESS...CEILINGS WILL IMPROVE BACK INTO VFR RANGE BY MONDAY AFTERNOON AND STAY VFR THROUGH THE END OF THIS TAF CYCLE. JORDAN PREV DISCUSSION... /ISSUED 326 PM CDT SUN APR 17 2016/ SHORT TERM... AS THE UA RIDGE STUBBORNLY HOLDS TOUGH ACROSS THE UPPER MID-WEST LATE THIS AFTN...IT CONTINUES TO BLOCK THE UA LOW ACROSS CO FROM MOVING MUCH...AS THE CENTER IS POISED TO EVEN RETROGRADE TO ACROSS THE CO/WY/UT COMMON BORDER BY TOMORROW MORNING...THUS MAINTAIN SWRLY FLOW ALOFT. THIS AFTN IS DEFINITELY MUCH QUIETER AS OPPOSED TO YESTERDAY/S BOUT WITH HEAVY RAINFALL...LARGE HAIL AND A TORNADO OR TWO ACROSS PORTIONS OF THE CWA...WITH THE SWATH OF HEAVY RAINFALL /AND SEVERE WEATHER THREAT/ HAVING SHIFTED TO E AND SE TX INTO E OK. CLOSER TO HOME...A COLD FRONT WHICH PUSHED SOUTH ACROSS THE REGION LAST NIGHT HAS RESULTED IN NRLY WINDS THAT WAS A BIT BREEZY EARLIER THIS MORNING THANKS TO A TIGHTENED PRESSURE GRADIENT. IN THE WAKE OF THE FROPA...A STRATUS DECK WAS SLOW TO SCOUR OUT WITH LINGERING LOW CLOUDS STILL OCCURRING ACROSS THE ERN SOUTH PLAINS AND ROLLING PLAINS PER 20Z VIS SATELLITE IMAGERY /FOG FINALLY CLEARED OUT AT KCDS/. ADDITIONAL STRATUS CLEARING IS EXPECTED THROUGHOUT THE REMAINDER OF THIS AFTERNOON INTO THIS EVENING...BUT HRRR ANALYSIS SUGGEST THAT CIGS WILL RISE TO MVFR CRITERIA ACROSS THE SERN TX PANHANDLE BY EARLY THIS EVENING BEFORE FINALLY DISSIPATING. FURTHERMORE...INTERMITTENT MIST/LIGHT RAIN HAS BEEN AFFECTING THE ROLLING PLAINS SINCE THIS MORNING AND WILL CONTINUE TO DO SO GIVEN THE UNSETTLED SW FLOW ALOFT ACTING ON MEAGER POST-FRONTAL MOISTURE. THE SLIGHT UL LIFT AND LOW-LEVEL MOISTURE HAS ALSO RESULTED IN THE DEVELOPMENT OF ISOLATED SHOWERS ACROSS THE FAR SRN TX PANHANDLE/NRN SOUTH PLAINS. NO LIGHTNING DETECTED AS OF YET BUT CAN NOT BE RULED OUT ESPECIALLY IN THE AREA RECEIVING BETTER INSOLATION. THE HRRR HINTS AT ADDITIONAL SHOWERY ACTIVITY LATER THIS AFTN ACROSS THE FAR SW TX PANHANDLE/NW SOUTH PLAINS...WHICH IS PLAUSIBLE AS THAT IS WHERE IT HAS CLEARED OUT FIRST. IN FACT...SLIGHT AGITATED CU-FIELDS HAVE DEVELOPED THERE. ALL OF THE PRECIP ACTIVITY THUS FAR HAS RESULTED IN A TRACE UP TO A FEW HUNDREDTHS OF AN INCH REPORTED VIA THE TTU MESONET SITES. THE FRONT HAS ALSO USHERED IN A COOLER AIRMASS WITH HIGHS IN THE 50S AND 60S...WHICH IS COOLER THAN WHAT WE HAVE EXPERIENCED IN RECENT DAYS. ALTHOUGH PWATS HAVE WANTED A BIT OVER THE PAST 24 HOURS...PWATS OF 0.50-1.00 INCH ACROSS THE NRN ROLLING PLAINS AND FAR ROLLING PLAINS COUPLED WITH A 250 MB 70+ KT JET MAX MOVING ACROSS THE REGION AND PROVIDING SOME UL SUPPORT...WILL MORE OR LESS MAINTAIN THE SHOWERY ACTIVITY /WITH PERHAPS A RUMBLE OF THUNDER/ ACROSS THE SAID AREA THROUGH THE EARLY EVENING HOURS. COULD SEE SHOWERS RE-GENERATE ELSEWHERE /HARD TO PIN-POINT THE EXACT LOCATION/ OVERNIGHT AS ANOTHER VORT LOBE EMBEDDED WITHIN THE SWRN PERIPHERY OF THE UA LOW...SWINGS OUT ACROSS THE AREA. OVERNIGHT LOWS WILL BE ON THE COOLER SIDE WITH UPPER 30S NW TO UPPER 40S SE EXPECTED. LOW CLOUDS MAY MAKE A RETURN OVERNIGHT/EARLY TOMORROW MORNING...BUT FOG COULD BE MORE HARD-PRESSED TO DEVELOP DUE TO SLIGHTLY BREEZY NRLY WIND SPEEDS. TOMORROW WILL BE SIMILAR TO TODAY /RELATIVELY CLOUDY WITH NORTH WINDS BECOMING BREEZY AT TIMES/ BUT PERHAPS A FEW DEGREES WARMER /60S AND 70S/. THE BEST MOISTURE AXIS SHIFTS TO THE SOUTH AND EAST OF THE CWA...BUT AN EMBEDDED IMPULSE MOVING ACROSS THE PERMIAN COULD SPARK SOME SHOWERS THERE...WHICH THEN COULD DRIFT ACROSS THE SRN ZONES. /29 LONG TERM... THE BROAD UPPER LOW OVER NORTHERN COLORADO WILL SLOWLY MOVE EAST THROUGH WEDNESDAY BEFORE GETTING CAUGHT UP BY A NORTHWEST FLOW SHORTWAVE AND SWEPT DOWNSTREAM AS AN OPEN TROUGH INTO THE MISSISSIPPI VALLEY THURSDAY. WITHIN THE PERSISTENT WEAK CYCLONIC FLOW WE WILL SEE A FEW LOW CHANCES FOR THUNDERSTORMS THROUGH WEDNESDAY. ONE RELATED TO A POSSIBLE WAVE ROTATING AROUND THE BASE OF THE LOW OUT OF NEW MEXICO INTO THE SOUTH PLAINS MONDAY NIGHT... WHICH THE WRF/NAM WORKS UP INTO A SMALL CONVECTIVE AREA BRUSHING OUR SOUTHEAST ZONES MONDAY NIGHT AND EARLY TUESDAY. THE AVN TAKE ON THIS WAVE IS FLATTER AND MORE CHANNELED SO LACKS ANY PRECIPITATION RESPONSE. WE WILL RETAIN A LOW MENTION FAVORING SOUTHEAST FOR NOW. ANOTHER WAVE IS EXPECTED TO ROTATE OUT OF THE FOUR-CORNERS REGION LATE TUESDAY AND ACROSS THE PANHANDLE WITH ENHANCED WESTERLY FLOW ACROSS THE AREA. BETTER SOLUTION AGREEMENT ON THIS ONE BEING CAPABLE OF SHOWER AND THUNDER ACTIVITY THOUGH MOISTURE CERTAINLY WILL BE MORE SHALLOW AND A DRY-LINE MIGHT EVEN BECOME A FACTOR. SO POSSIBLE WE COULD SEE LITTLE SIGNIFICANT ACTIVITY WEST OF THE DRY LINE ROUGHLY I-27 CORRIDOR AND A RISK OF SEVERE THAT AFTERNOON AND EVENING ACROSS THE ROLLING PLAINS. SITUATION REMAINS UNCERTAIN ENOUGH THAT WE WILL CONTINUE TO BROAD-BRUSH MODEST CONVECTIVE CHANCES FAVORING EASTERN AREAS LATE TUESDAY. A COLD FRONT SHOULD PUSH SOUTHWARD TUESDAY NIGHT AND MAY PROVIDE FOCUS FOR LINGERING THUNDER CHANCES INTO EARLY WEDNESDAY SOUTHERN AND EASTERN AREAS. THE MAIN UPPER LOW ALSO MOVING EAST-SOUTHEAST THAT DAY MAY PROVIDE MORE IMPETUS FOR SHOWER CHANCES FAVORING EASTERN ZONES WITH MODEL SOLUTIONS FUZZY ABOUT PRECIPITATION SEPARATION FROM EARLY WEDNESDAY. WE ALSO WILL NOT TRY TO BE TOO CUTE WITH A FAIRLY GENERIC COVERAGE UNTIL DETAILS UNFOLD. SHOWER CHANCES SHOULD DWINDLE WEDNESDAY NIGHT. ONE OF THE BIGGER CHANGES THIS RUN IS MORE CONFIDENCE IN A WARM AND DRY SPELL THURSDAY AND FRIDAY...PERHAPS INTO SATURDAY AS AN UPPER RIDGE JUTS NORTHWARD ACROSS THE SOUTHERN ROCKIES AND THEN OVER OUR AREA BY FRIDAY NIGHT. MOISTURE FLOW AROUND THE PERIPHERY OF THIS BUILDING RIDGE SEEMS A BIT MEAGER FOR NOW SO FORECAST WILL BE DRY UNTIL A POTENT LOOKING UPPER LOW BREAKS THROUGH THE ROCKIES LATE SATURDAY AND SPREADS LOW THUNDER CHANCES BACK ACROSS THE AREA SATURDAY NIGHT. BUT THIS CHANCE SHOULD BE BRIEF AS DEEP DRIER WESTERLY FLOW ALOFT OVERSPREADS THE AREA...AND RESULTS IN A WARM PERHAPS BREEZY OR WINDY DAY NEXT SUNDAY. SO...SOME CHANGES BASED ON PERSISTENT OR GATHERING TRENDS...THOUGH OVERALL CONFIDENCE IN DAY-TO-DAY PRECIPITATION IS MODEST AT BEST. /05 RMCQUEEN && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 14/93/14
AREA FORECAST DISCUSSION
NWS SEATTLE WA
300 PM PDT MON APR 18 2016 .SYNOPSIS...TUESDAY WILL BE ANOTHER DAY OF RECORD WARMTH AND SUNSHINE. A STRONG PUSH OF MARINE AIR IS LIKELY TO OCCUR ON WEDNESDAY. A WEATHER DISTURBANCE MAY BRING SCATTERED SHOWERS TO THE AREA WEDNESDAY AFTERNOON OR EVENING. ADDITIONAL WEATHER SYSTEMS SHOULD AFFECT THE REGION WITH A GOOD CHANCE OF SHOWERS AT TIMES INTO NEXT WEEKEND. && .SHORT TERM...ANOTHER RECORD WARM DAY IS LIKELY ON TUESDAY WITH SIMILAR TEMPS TO WHAT WERE SEEN TODAY. THE AIR MASS WILL BE THE SAME AND THERE ARE NO WEATHER SYSTEMS AFFECTING THE AREA...JUST A STRONG UPPER RIDGE AND THERMALLY INDUCED LOWER PRES AT THE SFC. THE FORECAST FOR WED IS FOR MUCH COOLER MARINE AIR TO ARRIVE... IF THE PUSH COMES TO THE INTERIOR LATE IN THE AFTERNOON THE FORECAST WILL OBVIOUSLY BE TOO COOL AND I WAS TEMPTED TO WARM UP THE FORECAST QUITE A BIT FOR WED BUT WILL LET SUBSEQUENT SHIFTS SEE ANOTHER MODEL RUN. A SHORTWAVE MOVING UP FROM OREGON SHOULD BRING SCATTERED SHOWERS AND A CHANCE FOR TSTMS WED AFTERNOON AND EVENING. THERE IS A GOOD CHANCE THAT ANY PRECIP WILL NOT ARRIVE TIL EVENING AND THAT ANY TSTMS WILL ONLY BE OVER THE MTNS. .LONG TERM...THERE IS A CHANCE THAT THERE WILL BE A COUPLE OF PERIODS OF SHOWERS OR RAIN IN THE EXTENDED PERIOD. OVER THE PAST FEW DAYS ONE GLOBAL MODEL OR ANOTHER HAS SHOWN A GOOD SOAKING RAIN...AND OTHER TIMES JUST LIGHT SCATTERED SHOWERS HAVE BEEN IN THE MODELS. TIMING IS USUALLY DIFFERENT WITH EACH RUN OF THE MODELS. && .AVIATION...AN UPPER RIDGE WILL REMAIN CENTERED OVER EASTERN WASHINGTON THROUGH TUE GIVING LIGHT SW FLOW ALOFT. AT THE SURFACE...HIGH PRES IS E OF THE CASCADES WHILE A THERMAL TROUGH OF LOW PRES IS ON THE WASHINGTON COAST. THIS IS GIVING LOW LEVEL OFFSHORE FLOW TO THE AREA. THE THERMAL TROUGH WILL MOVE INLAND ON TUE. THE AIR MASS IS STABLE AND DRY WITH ONLY SCATTERED TO BROKEN CIRRUS AND GOOD VISIBILITY ACROSS THE REGION. SOME PATCHY SHALLOW FOG MAY FORM ON THE WASHINGTON BEACHES LATE TONIGHT INTO TUE. ALBRECHT KSEA...HIGH CLOUDS AT TIMES. LIGHT W TO NW WIND AT 6 KT OR LESS WILL TURN TO THE NE AFTER 04Z. ALBRECHT && .MARINE...HIGH PRES WILL REMAIN CENTERED OVER EASTERN WASHINGTON THROUGH TUE. A THERMALLY INDUCED TROUGH OF LOW PRES SITTING ON THE WASHINGTON COAST WILL MIGRATE E INTO THE INLAND WATERS LATE TONIGHT AND TUE...THEN SHIFT E OF THE CASCADES TUE NIGHT OR WED. WEAK HIGH PRES IS OVER THE OFFSHORE WATERS BEHIND THE THERMAL TROUGH. EARLIER HRRR SOLUTIONS SHOWED SHALLOW FOG ENGULFING THE COASTAL WATERS LATER THIS EVENING THROUGH TUE MORNING. SATELLITE SHOWS THE FOG BANK OVER THE OFFSHORE WATERS...AND THE HRRR IS NOW BACKING OFF ON ITS EVENTUAL EASTWARD EXTENT. WILL CUT THE FOG COVERAGE TO PATCHY TONIGHT THROUGH TUE NIGHT. 12Z MODEL SOLUTIONS HAVE GENERALLY BACKED OFF ON THE STRENGTH OF THE MAIN MARINE PUSH THAT IS EXPECTED TO TAKE PLACE ON WED. FORECASTS WILL LIMIT SMALL CRAFT ADVISORY CONDITIONS TO THE CENTRAL AND EASTERN PORTIONS OF THE STRAIT OF JUAN DE FUCA WED NIGHT. ONSHORE FLOW WILL CONTINUE INTO THU AND THU NIGHT. ALBRECHT && .SEW WATCHES/WARNINGS/ADVISORIES... WA...NONE. PZ...NONE. && $$ WWW.WEATHER.GOV/SEATTLE YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS SEATTLE WA
840 AM PDT MON APR 18 2016 .SYNOPSIS...STRONG HIGH PRESSURE ALOFT ALONG WITH LOW LEVEL OFFSHORE FLOW WILL RESULT IN WARM SUNNY WEATHER THROUGH TUESDAY. A STRONG PUSH OF MARINE AIR WILL OCCUR ON WEDNESDAY AND A WEATHER DISTURBANCE MAY BRING SCATTERED SHOWERS TO THE AREA BY WEDNESDAY EVENING. ADDITIONAL WEATHER SYSTEMS SHOULD AFFECT THE REGION WITH SHOWERS AT TIMES THURSDAY THROUGH SUNDAY. && .SHORT TERM...A FRONT MOVING INTO B.C. WONT AFFECT WRN WA EXCEPT TO GIVE WRN WA SOME CIRRUS TODAY....BUT DESPITE SOME HIGH CLOUDS IT WILL BE SUNNY AND WARM. OFFSHORE FLOW THIS MORNING WILL TURN AROUND TO LIGHT NW FLOW OVER THE COASTAL WATERS BY THIS EVENING...AREAS OF FOG SHOULD DEVELOP ALONG THE COAST TONIGHT. ANY MORNING FOG ON THE COAST TUESDAY SHOULD QUICKLY BURN OFF AND WRN WA WILL HAVE ANOTHER SUNNY WARM DAY...IT SHOULD BE THE THIRD DAY OF 80 DEGREES OR WARMER FOR SEA TAC WHICH WILL BE A FIRST IN APRIL. ONSHORE FLOW WILL INCREASE THROUGH THE DAY ON WEDNESDAY ENDING ANY CHANCE FOR A FOURTH RECORD HIGH. MARINE STRATUS SHOULD SET UP ON THE COAST WED...AND THERE MAY BE INCREASING CLOUDS AND SCATTERED SHOWERS DEVELOPING IN THE AFTERNOON AND EVENING AS A SHORTWAVE TROUGH MOVES NORTH OUT OF OREGON. .LONG TERM...THE EURO AND GFS DIFFER QUITE ALOT IN THE DETAILS INTO THE WEEKEND...AND THE FORECAST FOR NOW IS JUST FOR A CHANCE OF SHOWERS EACH DAY. THE 00Z ECMWF DOES HAVE A GOOD SOAKING RAIN FOR WRN WA TIMED FOR SATURDAY NIGHT WHILE THE GFS IS JUST SHOWERY AT TIMES... MAINLY ON FRIDAY AND AGAIN SUNDAY. && .AVIATION...AN UPPER RIDGE WILL REMAIN CENTERED OVER EASTERN WASHINGTON THROUGH TUE GIVING LIGHT SW FLOW ALOFT. AT THE SURFACE...HIGH PRES IS E OF THE CASCADES WHILE A THERMAL TROUGH OF LOW PRES IS OVER THE COASTAL WATERS. THIS IS GIVING LOW LEVEL OFFSHORE FLOW TO THE AREA. THE AIR MASS IS STABLE AND DRY WITH ONLY SCATTERED TO BROKEN CIRRUS AND GOOD VISIBILITY ACROSS THE REGION. ALBRECHT KSEA...HIGH CLOUDS AT TIMES. NW WIND 6 KT OR LESS BECOMING NELY AFTER 04Z. ALBRECHT && .MARINE...HIGH PRES WILL REMAIN CENTERED OVER EASTERN WASHINGTON THROUGH TUE. A THERMALLY INDUCED TROUGH OF LOW PRES SITS OVER OUTER PORTIONS OF THE COASTAL WATERS THIS MORNING...THIS TROUGH WILL SHIFT EAST REACHING THE INLAND WATERS LATER TONIGHT AND TUE MORNING. THE THERMAL TROUGH WILL SHIFT E OF THE CASCADES DURING THE DAY TUE. WEAK HIGH PRES WILL BUILD OVER THE OFFSHORE WATERS BEHIND THE THERMAL TROUGH TONIGHT AND TUE. SOME WESTERLY FLOW CAN BE EXPECTED THROUGH THE STRAIT OF JUAN DE FUCA THIS EVENING AS THE THERMAL TROUGH SHIFTS EAST AND THERMAL GRADIENTS BECOME WESTERLY. BUT AT THIS TIME...EXPECT WINDS IN THE STRAIT TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THE LATEST HRRR SOLUTIONS SHOW FOG WITH LOW VISIBILITY FOLLOWING THE THERMAL TROUGH INTO THE COASTAL WATERS TONIGHT AND INTO TUE MORNING. THE MAIN PUSH OF MARINE AIR IS EXPECTED TO TAKE PLACE LATE TUE NIGHT OR WED AS A MODERATE TO STRONG SOUTHERLY SURGE DEVELOPS ON THE OREGON COAST THEN MOVES INTO THE COASTAL WATERS. WHILE FORECAST MODELS DO NOT INDICATE S WINDS TO SMALL CRAFT ADVISORY CRITERIA IN THE INNER COASTAL WATERS TUE NIGHT OR WED...THIS PATTERN SUPPORTS THE STRONGER SOUTHERLY FLOW THAT ACCOMPANIES A PUSH AFTER A WARM SPELL IN THE INTERIOR AND AN INCOMING UPPER LEVEL TROUGH. WILL CONSIDER BOOSTING WINDS ON WED FOR BOTH THE COAST AND PUGET SOUND AFTER LOOKING AT THE INCOMING 12Z MESOSCALE MODELS. A WEAK FRONT MAY PASS EAST ACROSS THE WATERS THU NIGHT OR FRI. ALBRECHT && .SEW WATCHES/WARNINGS/ADVISORIES... WA...NONE. PZ...SMALL CRAFT ADVISORY UNTIL NOON PDT TODAY FOR COASTAL WATERS FROM CAPE FLATTERY TO JAMES ISLAND OUT 10 NM-WEST ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA. && $$ WWW.WEATHER.GOV/SEATTLE YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
231 PM CDT MON APR 18 2016 .SHORT TERM... .TONIGHT AND TUESDAY - CONFIDENCE...MEDIUM FIRST ISSUE TONIGHT WILL BE MONITORING SOUTHWARD SAGGING BACK DOOR COLD FRONT INTO THE AREA AND MONITORING ANY POTENTIAL ACCELERATION ALONG THE LAKE WITH ABRUPT WIND SHIFT/TEMP DROPOFF. WATCHING THIS BOUNDARY ACROSS NE WI AND NOTE SOME INCREASING IN NORTHERLY GUSTS IN THE BAY AND DOOR COUNTY LOCALES THOUGH PRESSURE RISE AREA NOT IMPRESSIVE ATTM. MODELS TREND THIS BOUNDARY INTO SE WI THIS EVENING AND A WIND SHIFT TO THE NORTHEAST WITH SOME HIGHER LAKESIDE GUSTS LIKELY AND POTENTIAL FOR A FAIRLY SUBSTANTIAL TEMP DROPOFF. OTHERWISE LARGE UPPER LOW CONTINUES TO SPIN ACROSS THE ROCKIES. WATER VAPOR ALSO SHOWS CONVEYOR OF MOISTURE STREAMING NORTHWARD FROM TEXAS TO THE NORTHERN PLAINS. PRECIP IS ONLY AS CLOSE AS WESTERN IOWA AND THAT IS LIFTING MOSTLY NORTHWARD. TREND IN MODELS IS FOR THE MID LEVEL RIDGE AXIS TO BREAK DOWN SOMEWHAT HEADING INTO TUESDAY WHICH ALLOWS FOR SOME LEAD IMPULSES ON EASTERN PERIPHERY OF STORM SYSTEM TO SLIDE INTO WI. THERE ARE VARIOUS SOLUTIONS WITH RESPECT TO QPF WITH THE NAM THE DRIEST...BASICALLY SPLITTING PRECIP TO OUR NORTH AND SOUTH...AND THE GFS AND ECMWF WHICH GRADUALLY BRING SOME RAIN INTO SC WI LATER TONIGHT AND SPREAD THE CHANCE NORTHEAST THROUGH THE DAY. WILL TAKE A MIDDLE OF THE ROAD APPROACH TO POPS WITH THIS PROGRESSION. MUCH COOLER TEMPS CWA WIDE...ESP IN THE EAST WITH MORE CLOUDS AND POST FRONTAL COOLER AIRMASS WITH NE WINDS. .TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE IS MEDIUM. THE PLAINS UPPER LOW CONTINUES TO MOVE EAST TOWARD THE MID AND UPPER MISSISSIPPI VALLEY AND WEAKENS A LITTLE MORE. THE UPPER DIVERGENCE AND 700 MB UPWARD MOTION WEAKENS TUESDAY NIGHT...THEN INCREASES AGAIN WEDNESDAY AFTERNOON. 700 MB RH DRIES FROM THE WEST TUESDAY EVENING...THEN INCREASES WEDNESDAY AFTERNOON. THE LOWER LEVEL RH FROM 925 TO 850 MB REMAINS HIGH. THERE IS A LITTLE ELEVATED CAPE AROUND 50 JOULES/KG THAT BECOMES SURFACE BASED WEDNESDAY AFTERNOON APPROACHING 100 JOULES/KG. THE GFS AND ECMWF BRINGS VERY LIGHT PRECIPITATION ACROSS SOUTHERN WISCONSIN AT TIMES DEPENDED ON THE MODEL. HOWEVER ALL MODELS INCREASE THE PRECIPITATION WEDNESDAY...WITH THE 00Z ECMWF BEING THE FASTEST. THE SURFACE WINDS VEER MORE SOUTHEAST BUT CLOUD COVER SHOULD KEEP TEMPERATURES DOWN A LITTLE...WITH THE MAIN SURFACE WARM FRONT NEAR OR JUST SOUTH OF THE ILLINOIS BORDER. .WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE IS MEDIUM. THE PLAINS UPPER LOW BECOMES MORE PROGRESSIVE AS A MORE OPEN WAVE...AS IT MOVES ACROSS WISCONSIN AND ILLINOIS. THE UPPER LEVEL DIVERGENCE AND 700 MB UPWARD MOTION DECREASES DURING THE DAY THURSDAY. THE 700/850/925 MB RH STAYS HIGH. THE SURFACE AND 925 MB LOW CROSSES ACROSS FAR NORTHERN ILLINOIS THURSDAY. A DRY WEDGE OF THE RAIN PUSHES INTO SOUTHERN WISCONSIN LATER WEDNESDAY NIGHT BEFORE INCREASING AGAIN THURSDAY AFTERNOON WHEN GFS SOUNDINGS SHOW AROUND 500 JOULES/KG. .LONG TERM... .THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE IS MEDIUM. THE TROUGH MOVES ACROSS THE OHIO RIVER VALLEY AND GREAT LAKES REGION THURSDAY NIGHT AND FRIDAY MORNING. THE LIGHT RAIN ENDS THURSDAY EVENING BEFORE A SURFACE HIGH BUILDS INTO WISCONSIN. .SATURDAY AND SUNDAY...FORECAST CONFIDENCE IS MEDIUM. AN UPPER RIDGE BUILDS ACROSS THE PLAINS WITH A NORTHWEST FLOW ACROSS WISCONSIN SATURDAY WITH THE WEAKENING RIDGE MOVING INTO WISCONSIN SUNDAY. .MONDAY...FORECAST CONFIDENCE IS MEDIUM. A RATHER STRONG TROUGH MOVES ACROSS THE NORTHERN AND CENTRAL ROCKIES. THE GFS HAS A FASTER SHORTWAVE MOVING TOWARD THE MID MISSISSIPPI VALLEY. A STRONG SURFACE MOVES ACROSS KANSAS WHILE THE ECMWF HANGS THE LOW BACK OVER WESTERN KANSAS. BOTH THE GFS AND ECMWF HAVE THE MAIN SURFACE BOUNDARY ACROSS SOUTHERN OR CENTRAL ILLINOIS WITH A COOL EAST FLOW ACROSS SOUTHERN WISCONSIN WITH THE SURFACE HIGH ACROSS SOUTH CENTRAL CANADA. && .AVIATION/00Z TAFS/... CIRRUS SPILLING EWD FROM THE PLAINS SYSTEM. INLAND VFR CU FIELD WILL DISSIPATE WITH LOSS OF HEATING. MAIN STORY WILL BE WATCHING WIND SHIFT ASSOCIATED WITH BACK DOOR COLD FRONT SLIDING SOUTHWARD DOWN THE LAKE THIS EVENING. LATEST RAP BUFKIT STILL SHOWING FROPA ABOUT 02Z AT KMKE. WILL BE INTERESTING TO SEE IF THIS ENDS UP ACCELERATING DOWN THE LAKE PNEUMONIA STYLE. NO DOUBT AN ABRUPT WIND SHIFT TO THE NORTHEAST WITH SOME GUSTINESS POSSIBLE FOR A TIME. VFR CLOUD DECK EXPECTED TO INCREASE LATER TONIGHT INTO TUESDAY AS INFLUENCE OF THE MID LEVEL TROUGH NUDGES EVER SO SLOWLY CLOSER TO WI. THE CHANCE FOR SOME SHRA WILL RISE LATE TNGT FOR KMSN AND THEN EXPAND ACROSS SRN WI ON TUESDAY. NEW NAM SHOWS PRECIP TO BE QUITE SPOTTY WHILE GFS AND ECMWF SHOWING MORE COVERAGE. && .MARINE... WITH BACK DOOR COLD FRONT COMING DOWN THE LAKE THIS EVENING THERE WILL BE AN ABRUPT WIND SHIFT TO THE NORTHEAST WITH SOME HIGHER GUSTS POSSIBLE AS THE FRONT PASSES. A MARINE WEATHER STATEMENT MAY BE NEEDED BUT NOT ISSUING A SMALL CRAFT ADVISORY. OVERALL EXPECTING NORTHEAST WINDS 10-20 KNOTS WITH WAVES PREDOMINANTLY IN THE 2-4 FOOT RANGE. A NORTHEAST WIND WILL CONTINUE INTO TUESDAY THOUGH AT THIS POINT EXPECTING WINDS/WAVES TO BE BELOW THE SMALL CRAFT THRESHOLDS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TONIGHT/TUESDAY AND AVIATION/MARINE...COLLAR TUESDAY NIGHT THROUGH MONDAY...HENTZ
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1035 AM CDT MON APR 18 2016 .AVIATION/18Z TAFS/...CIRRUS SPILLING EWD FROM THE PLAINS SYSTEM. MAY SEE SOME CU POP UP AGAIN LIKE THE LAST COUPLE OF DAYS. MAIN STORY WILL BE WATCHING WIND SHIFT SLIDING SOUTHWARD DOWN THE LAKE THIS EVENING. RAP BUFKIT SHOWS ABOUT 02Z AT KMKE. WILL BE INTERESTING TO SEE IF THIS ENDS UP ACCELERATING DOWN THE LAKE PNEUMONIA STYLE. NO DOUBT AN ABRUPT WIND SHIFT TO THE NORTHEAST WITH SOME GUSTINESS POSSIBLE FOR A TIME. VFR CLOUD DECK EXPECTEDTO INCREASE LATER TONIGHT INTO TUESDAY AS INFLUENCE OF THE MID LEVEL TROUGH NUDGES EVER SO SLOWLY CLOSER TO WI. THE CHANCE FOR SOME SHRA WILL RISE LATE TNGT FOR KMSN AND THEN EXPAND ACROSS SRN WI ON TUESDAY. NEW NAM SHOWS PRECIP TO BE QUITE SPOTTY WHILE GFS AND ECMWF SHOWING MORE COVERAGE. PC && .MARINE...WINDS WILL SHIFT TO THE SOUTHEAST BY MIDDAY...LINGERING UNTIL AROUND SUNSET. THESE WINDS MAY INCREASE IN MAGNITUDE FOR A TIME THIS AFTERNOON. WINDS AND WAVES WILL REMAIN WELL BELOW SMALL CRAFT ADVISORY LEVELS. BACKDOOR COLD FRONT WILL MOVE SOUTHWARD ACROSS THE WATERS OF LAKE MICHIGAN THIS EVENING. A QUICK WIND SHIFT TO THE NORTHEAST IS EXPECTED AFTER THE FRONT PASSES THROUGH...WITH GUSTS OF 15 TO 20 KNOTS. THIS WILL BRING INCREASING WAVE HEIGHTS OF 2 TO 4 FEET FOR A TIME LATER TONIGHT INTO TUESDAY MORNING. HOWEVER...NOT EXPECTING THE WINDS AND WAVES TO REACH SMALL CRAFT ADVISORY LEVELS AT THIS TIME. HENTZ && .PREV DISCUSSION... /ISSUED 345 AM CDT MON APR 18 2016/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM. ANOTHER WARM DAY IS EXPECTED ACROSS THE AREA...AS THE 500 MB RIDGE AXIS SHIFTS SLOWLY TO THE SOUTHEAST. SOME HIGH CLOUDS WILL LINGER AT TIMES INTO THE AFTERNOON...WITH SOME DIURNAL CUMULUS DEVELOPMENT EXPECTED IN THE AFTERNOON AS WELL. DESPITE SOME CLOUDS...THERE SHOULD STILL BE A DECENT AMOUNT OF SUNSHINE. 925 MB TEMPERATURE FIELDS FROM MODELS SUGGEST HIGHS SHOULD BE IN THE UPPER 70S TO LOWER 80S AWAY FROM THE LAKE. ONSHORE WINDS DEVELOPING NEAR THE LAKE SHOULD KEEP HIGHS IN THE MID 60S TO LOWER 70S. BACKDOOR COLD FRONT SHOULD SLIDE SOUTHWARD ACROSS THE LAKESHORE COUNTIES AND NORTHEASTERN PORTIONS OF THE AREA THIS EVENING. THIS WILL BRING COOLER TEMPERATURES INTO THESE AREAS. NORTHEAST WINDS BEHIND THE FRONT MAY BE GUSTY AT TIMES THIS EVENING AND OVERNIGHT. MODELS CONTINUE TO BRING 500 MB VORTICITY MAXIMA NORTHEAST INTO THE AREA TONIGHT...WITH DECENT MID LEVEL Q VECTOR CONVERGENCE AND SOME FRONTOGENESIS RESPONSE FIELDS. THERE IS SOME DIFFERENCES WITH THE MODELS WITH TIMING AND PLACEMENT OF THESE FEATURES. STILL...AREA FORECAST SOUNDINGS SHOW A GRADUAL MOISTENING OF THE AIR COLUMN BY LATER TONIGHT. CONTINUED TO BRING IN CHANCE POPS BY LATER TONIGHT IN THE SOUTHWEST PORTIONS OF THE AREA...LOWER TO THE NORTHEAST. LONG TERM... THE CLOSED UPPER LOW WILL SIT OVER THE NORTHERN PLAINS ON TUESDAY. SHORTWAVE ENERGY OUT AHEAD OF THE UPPER LOW WILL INTERACT WITH A BAROCLINIC ZONE STALLED OVER NORTHERN WI AND PRODUCE SHOWERS OVER MAINLY NORTHERN WI ON TUE. SOUTHERN WI WILL SEE A CHANCE FOR SHOWERS MAINLY TOWARD THE IA/IL BORDER WITH A SURGE OF MOISTURE WORKING INTO THAT AREA. MODELS ARE SHOWING WEAK INSTABILITY SO KEPT MENTION FOR SLIGHT CHANCE OF THUNDER IN SOUTHERN HALF OF THE COUNTY WARNING AREA. PRECIP AMOUNTS LOOK QUITE LOW FOR TUE AND TUE EVENING. WEDNESDAY THROUGH THURSDAY... FORECAST CONFIDENCE MEDIUM. THE BETTER SURGE OF MOISTURE WILL ARRIVE IN SOUTHERN WI ON WEDNESDAY. THE UPPER LOW WILL TRACK THROUGH NEBRASKA AND SHORTWAVE ENERGY WILL ARRIVE IN SOUTHERN WI ON THE NOSE OF A LOW LEVEL JET AND ALSO AN UPPER JET. THE FORCING LOOKS MORE PROMISING AND THE WEIGHTED AVERAGE QPF BETWEEN THE MODELS IS AROUND A QUARTER INCH.. THAT WAVE OF PRECIP SHOULD KEEP TRACKING EAST THROUGH THE DAY. THERE IS STILL NOT A LOT OF INSTABILITY IN MODEL SOUNDINGS... BUT JUST ENOUGH TO KEEP MENTION OF THUNDER. PRECIP CHANCES TAPER OFF WED EVENING AS THE SURFACE LOW TRACKS ACROSS WI. LIGHT SHOWERS WILL BE POSSIBLE ALONG THE COLD FRONT THURSDAY AS THE LOW TRACKS EAST OF THE AREA. FRIDAY THROUGH SUNDAY... FORECAST CONFIDENCE MEDIUM. QUIET WEATHER WILL RETURN FOR FRIDAY WITH UPPER LEVEL RIDGING IN PLACE. LOW PRESSURE CROSSING THE ROCKIES WILL BRING FORCING FOR A FRONT TO SET UP OVER CENTRAL OR NORTHERN WI THIS WEEKEND. THAT FRONT WILL BE THE FOCUS FOR SHOWER CHANCES IN SOUTHERN WI ON SATURDAY IF YOU BELIEVE THE GFS OR SUNDAY IF THE ECMWF PANS OUT. THE ECMWF AND GFS BOTH KEEP THE BAROCLINIC ZONE IN THE VICINITY OF SOUTHERN WI EARLY NEXT WEEK WHICH WILL BRING MORE CHANCES FOR SHOWERS. STILL A LOT OF UNCERTAINTY THIS FAR OUT. AVIATION/12Z TAFS/... VFR CONDITIONS ARE EXPECTED TODAY AND TONIGHT ACROSS TAF SITES. LIGHT SOUTH WINDS ARE EXPECTED AT MADISON TODAY. SOUTH WINDS WILL BECOME SOUTHEAST AT THE EASTERN SITES BY MIDDAY...LINGERING UNTIL AROUND SUNSET. THESE WINDS MAY INCREASE IN SPEED SOMEWHAT ONCE THEY SHIFT SOUTHEAST. SOME HIGH CLOUDS THIS MORNING MAY LINGER INTO THE AFTERNOON...WITH SCATTERED DIURNAL CUMULUS CLOUDS DEVELOPING THIS AFTERNOON. BACKDOOR COLD FRONT WILL SLIDE SOUTHWARD ACROSS TAF SITES THIS EVENING...WITH WINDS SHIFTING QUICKLY TO THE NORTHEAST BEHIND IT INTO THE OVERNIGHT HOURS. GUSTS TO 15 KNOTS OR SO ARE EXPECTED AFTER THE FRONTAL PASSAGE THIS EVENING. MID LEVEL CLOUDS WILL CONTINUE TO INCREASE TONIGHT AND GRADUALLY LOWER...BECOMING OVERCAST LATE. ANY SHOWERS SHOULD REMAIN SOUTHWEST OF MADISON TONIGHT. MARINE... WINDS WILL SHIFT TO THE SOUTHEAST BY MIDDAY...LINGERING UNTIL AROUND SUNSET. THESE WINDS MAY INCREASE IN MAGNITUDE FOR A TIME THIS AFTERNOON. WINDS AND WAVES WILL REMAIN WELL BELOW SMALL CRAFT ADVISORY LEVELS. BACKDOOR COLD FRONT WILL MOVE SOUTHWARD ACROSS THE WATERS OF LAKE MICHIGAN THIS EVENING. A QUICK WIND SHIFT TO THE NORTHEAST IS EXPECTED AFTER THE FRONT PASSES THROUGH...WITH GUSTS OF 15 TO 20 KNOTS. THIS WILL BRING INCREASING WAVE HEIGHTS OF 2 TO 4 FEET FOR A TIME LATER TONIGHT INTO TUESDAY MORNING. HOWEVER...NOT EXPECTING THE WINDS AND WAVES TO REACH SMALL CRAFT ADVISORY LEVELS AT THIS TIME. FIRE WEATHER... ANOTHER DAY OF LOW RELATIVE HUMIDITY VALUES IN THE 23 TO 28 PERCENT RANGE ARE EXPECTED ACROSS THE AREA...WITH TEMPERATURES REACHING THE UPPER 70S TO LOWER 80S. WINDS WILL REMAIN RELATIVELY LIGHT...SOUTH INLAND AND BECOMING SOUTHEAST NEAR LAKE MICHIGAN BY MIDDAY. FUELS CONTINUE TO DRY OUT...SO IT WILL BE ANOTHER DAY OF ELEVATED FIRE WEATHER CONCERN. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...WOOD TUESDAY THROUGH SUNDAY...MRC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1141 PM CDT SUN APR 17 2016 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SYNOPSIS... ISSUED AT 217 PM CDT SUN APR 17 2016 UNSEASONABLY WARM AGAIN TOMORROW...THEN TEMPERATURES SETTLING BACK CLOSER TO SEASONAL NORMALS. THE UPR FLOW ACRS NOAM IS SPLIT. A VERY BLOCKY SRN STREAM WAS S OF 55N...WITH A MORE ZONAL NRN STREAM ACRS CANADA. THE NORTHERN STREAM WILL BECOME MUCH MORE BLOCKY WITH TIME...WHILE THE SOUTHERN STREAM BECOMES SLOWLY PROGRESSIVE. UNSEASONABLY WARM AIR WILL REMAIN IN PLACE ANOTHER DAY...THEN TEMPERATURES WILL TREND DOWNWARD DUE TO THE ARRIVAL OF COOLER AIR FROM CANADA...E/NE FLOW ACROSS THE LAKES...AND MORE CLDS. STILL...READINGS SHOULD AT LEAST BE CLOSE TO NORMAL...AND NOT AS CHILLY AS DURING THE FIRST WEEK OF APRIL. THE COLD FRONT AT THE LEADING EDGE OF THE COOLER AIR DOES NOT LOOK LIKE A GOOD PRECIPITATION PRODUCER. BUT RAIN CHCS WL BE BETTER WHEN REMNANTS OF THE UPR LOW CURRENTLY COMPRISING THE WRN LEG OF SRN STREAM BLOCK CROSS THE REGION MID-WEEK. BEST GUESS IS THAT PCPN AMNTS WL RANGE FM BLO NORMAL ACRS THE NE PART OF THE AREA...TO NR NORMAL ACRS THE SW. && .SHORT TERM...TONIGHT AND MONDAY ISSUED AT 217 PM CDT SUN APR 17 2016 THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A 500MB RIDGE AXIS FROM THE CENTRAL GULF OF MEXICO TO THE CENTRAL GREAT LAKES. A BROAD SURFACE HIGH EXISTS GENERALLY EAST OF THE MISSISSIPPI RIVER AND CONTINUES TO PUMP WARM AND DRY AIR NORTHWARD ACROSS WISCONSIN. TO THE NORTH AND WEST...A COLD FRONT HAS STALLED OVER LAKE SUPERIOR AND NORTHERN MINNESOTA...WHILE ANOTHER STALLED BOUNDARY EXTENDS SOUTH ACROSS THE CENTRAL PLAINS. FORECAST CONCERNS INCLUDE TEMPS AND FIRE WX. TONIGHT...LITTLE CHANGES TONIGHT. UPPER RIDGE WILL HOLD FIRM ACROSS THE REGION. SOUTHERLY WINDS AT THE SURFACE WILL LEAD TO MILD NIGHT. AREAS OF MID-LEVEL CLOUDS WILL LIKELY DRIFT OVER NORTH-CENTRAL WI FROM TIME TO TIME...BUT SHOULDNT IMPACT TEMPS MUCH. LOWS MAINLY IN THE MIDDLE 40S TO LOWER 50S. MONDAY...A SHORTWAVE MOVING ACROSS ONTARIO WILL PUSH A COLD FRONT SLOWLY INTO NORTHERN WISCONSIN BY LATE IN THE MORNING. MODELS APPEAR SLIGHTLY SLOWER WITH THE ARRIVAL OF THE FRONT...WHICH SHOULD SUPPORT TEMPERATURES RISING INTO THE MID AND UPPER 70S OVER CENTRAL AND EAST-CENTRAL WI. NORTHERN WI IS MORE TRICKY DUE TO TIMING ISSUES...AND THE FACT THAT THE TEMP GRADIENT LAGS BEHIND THE FRONT SOME. MOST GUIDANCE SUPPORTS TEMPS RISING INTO THE MID 60S TO LOWER 70S OVER NORTHERN WI BEFORE THIS TEMP GRADIENT ARRIVES...SO WILL GIVE TEMPS A BOOST. DO THINK TEMPS WILL MAX OUT AROUND MIDDAY OVER VILAS CO...AND IN THE ROUTE 8 CORRIDOR BY EARLY AFTERNOON. FAR NE WI WILL LIKELY SEE A QUICK TEMP DROP BY MID TO LATE AFTERNOON AS CLOUDS PUSH IN AND WINDS SHIFT TO THE NE. DRY AIR AHEAD OF THE FRONT WILL LIMIT SHOWER COVERAGE...BUT SOME CAPE UP TO 200 J/KG NOTED ON PROGGED SOUNDINGS COULD LEAD TO LOW END SCT COVERAGE DURING THE AFTERNOON ACROSS NORTHERN WI. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 217 PM CDT SUN APR 17 2016 MAIN LONG-TERM FCST CONCERN IS PCPN POTENTIAL WITH AS UPR TROF SLOWLY CROSSES THE REGION MID WEEK. THE BEST FORCING FM THE FEATURE WL LIKELY PASS THROUGH TO THE S OF THE AREA. IN ADDITION...PCPN WL PROBABLY HAVE TO FIGHT THROUGH DRY AIR AT LOW- LEVELS FEEDING BACK INTO THE AREA FM ANTICYCLONE PASSING THROUGH TO THE NE OF THE REGION. THE UPR TROF WL STILL PROBABLY GENERATE SCT SHRA AT TIMES...THOUGH HONING IN ON EXACTLY WHEN THEY WL OCCUR IS DIFFICULT. THE GREATEST CHC/HIGHEST COVERAGE OF THE SHRA WL BE OVER THE SW PART OF THE FCST AREA...WITH DECRG RAIN CHCS TO THE NE. CONFIDENCE IN THE PATTERN EVOLUTION AND THIS OVERALL SCENARIO IS HIGH...THOUGH CONFIDENCE ON POPS IN ANY GIVEN FCST PERIOD IS RATHER LOW. THERE WL PROBABLY BE AT LEAST A DAY OF DRY WX AT THE END OF THE WEEK...BEFORE THE NEXT SYSTEM APPROACHES FM THE W. NO SIG CHGS TO THE STANDARD EXTENDED FCST INITIALIZATION GRIDS BASED ON A BROAD BLEND OF GUIDANCE PRODUCTS. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1141 PM CDT SUN APR 17 2016 MID AND HIGH CLOUDS WILL INCREASE FROM NORTH TO SOUTH MONDAY ALONG A COLD FRONT DROPPING IN FROM THE NORTH. A CHANCE OF SHOWERS WILL ARRIVE DURING THE AFTERNOON OVER NORTHERN WI ALONG THE FRONT...MAINLY AFFECTING RHI. THE REST OF THE TAF SITES SHOULD STAY DRY WITH THE FROPA AS MOISTURE WILL BE LIMITED. WINDS WILL BE SHIFTING TO THE NORTHEAST OVER THE TAF SITES MONDAY AFTERNOON AND EVENING BEHIND THE FRONT. && .FIRE WEATHER... ISSUED AT 217 PM CDT SUN APR 17 2016 ANOTHER VERY WARM AND DRY DAY THANKS TO SURFACE HIGH PRESSURE YIELDED RELATIVE HUMIDITIES BETWEEN 25 AND 30 PERCENT OVER MUCH OF CENTRAL AND NORTH-CENTRAL WI TODAY. EVEN THOUGH A WEAK COLD FRONT WILL BE DROPPING SOUTH OVER THE REGION ON MONDAY AFTERNOON...WARM AND DRY CONDITIONS WILL PERSIST AHEAD FRONT. RELATIVE HUMIDITIES MAY STILL FALL BETWEEN 25 AND 30 PERCENT OVER CENTRAL WI AND THE WESTERN FOX VALLEY BEFORE WINDS SHIFT TO THE NORTHEAST LATE IN THE AFTERNOON OR EARLY IN THE EVENING. A SHOWER OR TWO REMAINS POSSIBLE...MAINLY NORTH OF ROUTE 29 AND OVER DOOR CO. COOLER WEATHER WILL RETURN ON TUESDAY. GRASSES AND OTHER FINE FUELS WILL CONTINUE TO DRY OUT THROUGH MONDAY ...LEADING TO ELEVATED FIRE DANGER. THE WORST CONDITIONS ARE ANTICIPATED IN THE SANDY SOIL REGIONS OF CENTRAL WISCONSIN...BUT SPOTTY GRASS FIRES MAY DEVELOP EVEN OVER EASTERN WISCONSIN TOWARD LAKE MICHIGAN. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS.......SKOWRONSKI SHORT TERM.....MPC LONG TERM......SKOWRONSKI AVIATION.......KURIMSKI FIRE WEATHER...MPC
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
331 AM CDT WED APR 20 2016 .SHORT TERM... 329 AM CDT THROUGH TONIGHT... THIS AFTERNOON AND EVENING WILL BRING THE HIGHEST CHANCE FOR SHOWERS IN THE FORECAST AREA IN TEN DAYS. WE HAVE KEPT THE MAIN THEME OF RAIN TIMING BEING MID- AFTERNOON THROUGH EVENING SPREADING FROM WEST TO EAST AND JUST REFINING THAT TO THE HOURLY LEVEL. DID INCREASE THE THUNDER POTENTIAL SOME OVER THE ILLINOIS PART OF THE CWA THOUGH THE RISK FOR SEVERE WEATHER REMAINS QUITE LOW. THE PERSISTENT LARGE UPPER LOW IS GYRATING ITS WAY SLOWLY EAST THIS MORNING WITH ITS CENTER NOW OVER THE CENTRAL PLAINS. A 90 KT UPPER JET ROUNDING THE SOUTHERN EDGE OF THIS CENTER AND ASSOCIATED DEEP PV ANOMALY THIS MORNING WILL HELP RE-DEEPEN THE LOW CENTER BY THIS EVENING OVER IOWA. UPPER FORCING AND ASSOCIATED LIFT IN ADVANCE OF THIS...ALONG WITH A LOW-LEVEL RESPONSE OF THETA-E ADVECTION...WILL SPREAD OVER ILLINOIS DURING THE AFTERNOON. GIVEN THIS WILL BE DURING THE PEAK HEATING TIME...EXPECT THAT THERE WILL BE AN INCREASE IN SHOWER AND STORM ACTIVITY...LIKELY JUST WEST OF THE CWA ALONG THE SYSTEM COLD FRONT DURING THE EARLY TO MID AFTERNOON AND SPREADING EAST FROM THERE. CONVECTIVE ALLOWING MODELS SUCH AS THE HRRR INDICATE THIS INCREASE AND TIMING...THOUGH HAVE VARIED QUITE A BIT FROM RUN-TO-RUN ON THE COVERAGE. A FEW THINGS COULD INDEED LIMIT AFTERNOON SHOWER/STORM COVERAGE SUCH AS THE NARROW NATURE OF THE DEEP MOIST PLUME WRAPPING NORTHWARD INTO THIS SYSTEM. OVERALL THOUGH EXPECT THE AFOREMENTIONED FORCING JUST AHEAD OF THE SYSTEM DRY SLOT TO BE ENOUGH TO PROVIDE AN UPTICK IN SHOWERS DURING THE AFTERNOON INTO EARLY EVENING...WARRANTING LIKELY WORDING IN THE FORECAST. THE INSTABILITY MAGNITUDES /A FEW HUNDRED J/KG/ ARE BETTER FOR THUNDER THAN PREVIOUS FORECAST CYCLES...MAINLY FOR THE NORTH CENTRAL ILLINOIS PART OF THE FORECAST AREA. THE TIMING OF THE MAIN SHOWER AND POSSIBLE THUNDERSTORM AREAS APPEAR TO BE EARLY ENOUGH TO PREVENT DEEPER INSTABILITY RETURN TO LEVELS THAT WOULD WARRANT A THREAT FOR SEVERE STORMS...THOUGH A FEW STRONG ONES WITH MAYBE SOME SMALL HAIL ARE POSSIBLE INTO THE WESTERN CWA WITH FREEZING LEVELS A LITTLE BELOW 10KFT. IN TERMS OF TEMPERATURES...THE FRONTAL BOUNDARY WHICH BROUGHT A 30 DEGREE TEMPERATURE GRADIENT ACROSS THE CWA YESTERDAY...IS NOW DRAPED OVER CENTRAL ILLINOIS TO SOUTHERN INDIANA. THIS WILL LIFT NORTHWARD AS A WARM FRONT TODAY. THE FRONTAL PROGRESSION WILL PROBABLY NOT BE FAR AHEAD OF RAIN SHOWER ACTIVITY WHICH MAKES THE TEMPERATURE FORECAST CHALLENGING. NORTHERN AREAS WILL CERTAINLY BE WARMER THAN YESTERDAY BUT HOW MUCH SO WILL DEPEND ON THE FRONTAL PASSAGE TIMING. ONSHORE FLOW A GOOD PART OF THE DAY FROM CHICAGO NORTHWARD WILL KEEP LAKESIDE TEMPERATURES COOLER AGAIN. FAR SOUTHERN AREAS HAVE THE CHANCE AGAIN TO REACH UPPER 70S. AS THE SYSTEM DRY SLOT WORKS OVERHEAD LATE THIS EVENING INTO OVERNIGHT...THE SHOWER ACTIVITY WILL PUSH NORTHEAST. THE LOW-LEVEL COOL ADVECTION WILL ACTUALLY WEAKEN GIVEN THE OVERALL OCCLUDED NATURE OF THIS SYSTEM...SO LOWS LOOK TO REMAIN IN THE 50S AREAWIDE. MTF && .LONG TERM... 329 AM CDT THURSDAY THROUGH TUESDAY... THE PRIMARY UPPER LOW WILL GRADUALLY TRANSITION INTO AN OPEN WAVE THROUGH THURSDAY AND THURSDAY NIGHT AND SHOULD DO SO AS IT TRACKS EASTWARD OVER THE FORECAST AREA. WHILE DRY AIR ALOFT WILL PREVENT MUCH FOR SHOWERS THURSDAY MORNING...MOST MODEL GUIDANCE INDICATES THE FORECAST AREA TO BE IN A FAVORABLE AREA OF UPPER SUPPORT TO AT LEAST SEE AFTERNOON AND EARLY EVENING SCATTERED SHOWERS AND EVEN A FEW STORMS AGAIN. WITH TEMPERATURES THURSDAY AFTERNOON WARMING BACK INTO THE MID 60S TO LOW 70S...THERE SHOULD BE A FEW HUNDRED J/KG OF CAPE TO WORK WITH. LOWER FREEZING LEVELS COULD PROVIDE A FEW SMALL HAIL PRODUCERS. BEHIND THIS TROUGH FRIDAY AND SATURDAY CONTINUE TO LOOK DRY. STOUT NORTHEAST WINDS ON FRIDAY WILL KEEP LAKESHORE HIGHS INCLUDING DOWNTOWN CHICAGO LIKELY SHY OF 50 DEGREES. INLAND AREAS ARE PRESENTLY FORECAST FOR HIGHS IN THE UPPER 50S/LOWER 60S...ALTHOUGH THIS WILL DEPEND ON CLOUDS CLEARING FRIDAY MORNING. GIVEN THE PRESENT AMPLIFIED/SEMI-BLOCKED PATTERN ACROSS THE EASTERN PACIFIC AND CONUS...CONFIDENCE IN THE LONGER TERM PATTERN EVOLUTION REMAINS LOW. A MASSIVE UPPER LOW/TROUGH IS EXPECTED ACROSS EASTERN CANADA AND THIS WILL PROVIDE NORTHWEST FLOW INTO THE GREAT LAKES...WHILE AN UPPER LOW OVER THE SOUTHWEST U.S. IS ANTICIPATED TO SLOWLY WORK ITS WAY EAST. TOGETHER THESE SHOULD DEVELOP A WEST-TO-EAST BAROCLINIC ZONE ACROSS THE MIDWEST THOUGH WHERE AND HOW ACTIVE REMAINS HIGHLY UNCERTAIN ON MODELS. THIS ALSO LEADS TO LOW CONFIDENCE IN TEMPERATURE FORECASTS AS A LARGE RANGE IS LIKELY ACROSS THIS BOUNDARY. RIGHT NOW HAVE FAVORED A BLEND OF THE EC/GFS/GEM...WHICH BRINGS THE BOUNDARY INTO THE AREA MONDAY AND JUST SOUTH BY TUESDAY. MTF && .AVIATION... FOR THE 06Z TAFS... A STORM SYSTEM TO OUR WEST WILL LIFT A WARM FRONT NORTHWARD OVER THE TERMINALS BY THIS EVENING. THIS WILL LIKELY RESULT IN OUR BEST CHANCE FOR A PERIOD OF SHOWERS AND SOME THUNDERSTORMS OVER NORTHERN ILLINOIS/NORTHWESTERN INDIANA LATER TODAY INTO THIS EVENING. AS SUCH...I HAVE TWEAKED THE TIMING OF THE PRECIPITATION IN THE TAFS TO HIT THE LATE AFTERNOON THROUGH MID EVENING HOURS WITH SHOWERS. WE ALSO CANNOT RULE OUT SOME THUNDERSTORMS AS WELL WITH THIS BATCH OF SHOWERS...AS A MID-LEVEL DRY SLOT SHIFTING INTO THE REGION SHOULD HELP STEEPEN THE MID-LEVEL LAPSE RATES. AT THIS TIME I HAVE OPTED TO HOLD OFF INCLUDING THE THUNDER IN A TEMPO...BUT THE BEST CHANCES OF THUNDER WOULD LIKELY FALL IN THE CURRENT 00-03 UTC (22-01 UTC) TEMPO GROUPS AT THE EASTERN (KRFD) TAF SITES. WINDS THROUGH THE DAY WILL REMAIN EAST-SOUTHEASTERLY...AND AGAIN COULD BECOME A BIT GUSTY DURING THE DAY. AS THE WARM FRONT LIFTS NORTHWARD THIS EVENING THE WINDS SHOULD BECOME SOUTH-SOUTHWESTERLY. A PERIOD OF MVFR CIGS COULD ALSO ACCOMPANY THE WARM FRONTAL BOUNDARY. KJB && .MARINE... 228 AM CDT A WEAK AREA OF LOW PRESSURE IS EXPECTED TO MOVE EASTWARD OVER LAKE MICHIGAN ON THURSDAY. AS THIS LOW MOVES OVER THE LAKE...LIGHT WINDS AND A MOIST AIR MASS COULD PRODUCE A PERIOD OF FOG OVER THE LAKE. HOWEVER...NORTHERLY WINDS ARE EXPECTED TO INCREASE FROM NORTH TO SOUTH OVER THE LAKE THURSDAY NIGHT INTO FRIDAY FOLLOWING THE EASTWARD PASSAGE OF THE SURFACE LOW. THIS SHOULD RESULT IN A PERIOD OF 30 KT NORTHERLY WINDS ON FRIDAY BEFORE WINDS ABATE FRIDAY NIGHT AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS OVER THE UPPER GREAT LAKES. LARGE WIND WAVES...LIKELY IN EXCESS OF 5 FEET ON SOUTHERN LAKE MICHIGAN WILL RESULT IN OUR NEXT PERIOD OF SMALL CRAFT ADVISORY CONDITIONS FOR THE ILLINOIS AND INDIANA NEAR SHORE WATERS. OVER THE WEEKEND ANOTHER COLD FRONT IS EXPECTED TO SHIFT SOUTHWARD DOWN LAKE MICHIGAN. THERE IS STILL UNCERTAINTY ON THE EXACT TIMING OF THIS FRONT. HOWEVER...THERE ARE INDICATIONS THAT ANOTHER PERIOD OF STRONGER NORTH-NORTHEASTERLY WINDS WILL SET UP OVER THE LAKE POSSIBLY BY LATE SUNDAY OR MONDAY. THIS WILL BE ANOTHER PERIOD TO WATCH FOR POSSIBLE SMALL CRAFT CONDITIONS ON THE NEAR SHORE WATERS DUE TO WINDS AND HIGH WAVES. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM WEDNESDAY. && $$ 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
1252 AM CDT WED APR 20 2016 .UPDATE... 855 PM CDT FRONTAL BOUNDARY BEGAN TO SAG SOUTH ACROSS NORTHERN IL/NORTHWEST IN EARLIER TODAY AND RESULTED IN A WIND SHIFT FROM THE SOUTH/SOUTHWEST TO NORTH/NORTHEAST...COUPLED WITH MUCH COOLER AIR FLOWING INTO NORTHERN IL. TEMPERATURES QUICKLY FELL INTO THE LOW/MID 50S...MEANWHILE SOUTH OF THE BOUNDARY TEMPERATURES WERE HOLDING IN THE 70S. THE BOUNDARY HAS PUSHED SOUTH OF THE FORECAST AREA INTO CENTRAL IL TONIGHT...AND IS EXPECTED TO BECOME STATIONARY OVERNIGHT. SCATTERED SHOWERS ACROSS NORTHWEST IL HAVE STEADILY DIMINISHED IN COVERAGE AND INTENSITY...AND LATEST HI-RES FORECAST GUIDANCE CONTINUES TO LEAN TOWARDS PRECIP COMING TO AN END OVERNIGHT THROUGH DAYBREAK WED. WITH HIGH PRESSURE POSITIONED OVER LOWER MICHIGAN TO JAMES BAY...THIS MAY ALLOW FOR SOME POCKETS OF DRIER AIR AND LESS CLOUD COVER OVERNIGHT...BUT ANY BREAKS WILL BE SHORT LIVED. A WEAK SHORT WAVE IS PROGGED TO DEVELOP OVER THE CENTRAL PLAINS LATE TONIGHT AND WILL HELP TO ENERGIZE THE FRONTAL BOUNDARY...LIFTING THE BOUNDARY BACK NORTH WEDNESDAY AND BRINGING AN INCREASING CHANCE FOR PRECIP BY MID-MORNING. TIMING OF THE FRONTAL BOUNDARY WED WILL DICTATE HIGH TEMPS...BUT CURRENTLY EXPECTING HIGHS TO PUSH BACK INTO THE UPPER 60S TO LOW 70S. THE BETTER CHANCE FOR SHOWERS AND POSSIBLY THUNDERSTORMS WILL ARRIVE IN THE WED AFTERNOON TIMEFRAME. BEACHLER && .SHORT TERM... 236 PM CDT THROUGH TODAY... FOR THE REMAINDER OF THE AFTERNOON AND INTO THE EVENING...THE MAIN FOCUS WILL BE PCPN EXTENT AND TEMPERATURE DISTRIBUTION. AS OF 230PM CDT...WITH A WEAK TROUGH OF LOW PRESSURE ACROSS THE MISSOURI VALLEY AND STRONG HIGH PRESSURE OVER THE UPPER GREAT LAKES...ALONG WITH A WEAK FRONTAL BOUNDARY ROUGHLY ALONG THE ILLINOIS AND KANKAKEE RIVER VALLEYS...THERE HAS BEEN QUITE A SPREAD IN TEMPERATURES ACROSS THE REGION. WITH PREVAILING NORTHEASTERLY FLOW OFF OF THE COOL WATERS OF LAKE MICHIGAN NORTH OF THE BOUNDARY...AND SOUTHERLY FLOW TO THE SOUTH...TEMPERATURES ACROSS THE SOUTHERN PORTIONS OF THE CWA ARE IN THE MIDDLE TO UPPER 70S...WITH SOME LOCATIONS POSSIBLY SEE 80F AGAIN TODAY. HOWEVER...NORTH OF THE BOUNDARY...TEMPERATURES ARE MUCH LOWER...WITH HIGHS TODAY TOPPING OUT ONLY IN THE LOWER 50S. A FEW LAKEFRONT LOCATIONS MAY ONLY SEE TEMPS REACH THE UPPER 40S. PERSISTENT RAIN HAS BEEN FALLING OVER MUCH OF NWRN IL...WITH THE MOST WIDESPREAD RAIN INVOF A VORT MAX SLOWLY LIFTING NEWD. EXPECT THAT THE VORT WILL EVENTUALLY LIFT INTO WISCONSIN AND PCPN CHANCES SHOULD DIMINISH THROUGH THE NIGHT. WHILE THERE WILL STILL BE SOME RESIDUAL CHANCE FOR SOME SHOWERS OVERNIGHT ...ESPECIALLY WEST OF THE I-39 CORRIDOR...NERN IL AND NWRN IN SHOULD REMAIN DRY. HOWEVER...THERE IS A CHANCE FOR AN ISOLD SHOWER THROUGH THIS EVENING OVER THE CHICAGO METRO AREA. WITH A RELATIVELY MOIST AIRMASS AND THICK CLOUD COVER EXPECTED TO REMAIN IN PLACE OVERNIGHT...TEMPERATURES SHOULD REMAIN RELATIVELY MILD. OVERNIGHT LOWS ACROSS THE AREA SHOULD RANGE FROM THE UPPER 50S OVER THE PONTIAC METRO AREA TO THE UPPER 40S TO LOWER 50S OVER THE REMAINDER OF THE AREA. KREIN && .LONG TERM... 308 PM CDT WEDNESDAY THROUGH FRIDAY... LINGERING SHOWER CHANCES WILL REMAIN WEDNESDAY MORNING PRIMARILY ACROSS NORTHERN ILLINOIS...WHILE WEAK ENERGY CONTINUES TO LIFT NORTH OUT AHEAD OF APPROACHING LARGE UPPER LEVEL SYSTEM OVER THE PLAINS. HOWEVER...COVERAGE/DURATION WILL REMAIN LOW WITH THIS WEAK ASCENT...AND SO HAVE KEPT POPS LOW DURING THIS TIME. SLOWLY INCREASE POPS THROUGH MIDDAY AND EARLY AFTERNOON WEDNESDAY AS THIS SYSTEM WORKS ITS WAY EAST AND WHILE STRONGER ENERGY WRAPS AROUND THIS SYSTEM. THIS WILL OCCUR AS FRONTAL BOUNDARY LIFTS NORTH THROUGH THE CWA AND WITH DEWPOINTS REBOUNDING BACK INTO THE 50S. THIS SHOULD ALLOW COVERAGE OF SHOWERS TO INCREASE OVER MUCH OF NORTHERN ILLINOIS...ESPECIALLY BY THE LATE AFTERNOON TIME FRAME. INSTABILITY WILL INCREASE DURING THE AFTERNOON BUT WILL REMAIN ON THE LOW SIDE. HOWEVER...WITH INCREASING FORCING ALOFT...DO THINK THUNDERSTORM CHANCES WILL REMAIN. DO THINK TEMPS WILL REBOUND ACROSS THE CWA ON WEDNESDAY WITH BOUNDARY LIFTING NORTH...SO RAISED HIGH TEMPS WITH MOST LOCATIONS GETTING INTO THE UPPER 60S WITH THE EXCEPTION OF AREAS NEAR THE LAKE IN NORTHEAST ILLINOIS. PUSH OF PRECIP WEDNESDAY AFTERNOON WILL CONTINUE TO LIFT NORTHEAST THROUGH THE EARLY EVENING AS THIS ENERGY PUSHES THROUGH. SYSTEM WILL BECOME MORE STACKED DURING THE NIGHT WITH THE SURFACE LOW WEAKENING AS IT MOVES INTO THE CWA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING. THIS SHOULD ALLOW FOR COVERAGE OF ANY PRECIP TO LOWER WITH A DRY PERIOD POSSIBLE FOR MOST AREAS. HOWEVER...THIS UPPER LEVEL TROUGH WILL QUICKLY OPEN UP AS IT SWINGS THROUGH THE CWA ON THURSDAY. LINGERING HIGHER DEWPOINTS ALONG SURFACE TROUGH AXIS WITH THIS ADDITIONAL FORCING WILL ALLOW FOR ADDITIONAL SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TO DEVELOP BY LATE THURSDAY MORNING INTO THE AFTERNOON. GIVEN THE ANTICIPATED COVERAGE AT THIS TIME DID NOT RAISE POPS TOO HIGH...BUT COULD SEE THEM RAISED FURTHER WITH LATER FORECASTS. THIS PRECIP IS EXPECTED TO DIMINISH AS IT EXITS TO THE EAST THURSDAY EVENING WITH THE DEPARTURE OF THIS SYSTEM. DID LEAVE A SLIGHT CHANCE FOR SHOWERS THURSDAY NIGHT AS SOME ISOLATED DEVELOPMENT COULD OCCUR ALONG SOUTHWARD DRIFTING BOUNDARY. BUILDING HIGH PRESSURE WILL THEN BRING PERIOD OF DRY WEATHER TO THE AREA FRIDAY. FRIDAY NIGHT THROUGH TUESDAY... QUIET AND NEAR TO SLIGHTLY ABOVE LATE APRIL NORMAL TEMPERATURES WILL BE IN STORE TO START THE WEEKEND. EXPECTING HIGHS IN THE MID TO UPPER 60S INLAND ON SATURDAY. WITH HIGH PRESSURE NEARBY...WINDS SHOULD STAY ONSHORE FOR AT LEAST THE ILLINOIS SHORE KEEPING TEMPERATURES IN THE 50S THERE. ATTENTION WILL THEN TURN TO A MID/UPPER TROUGH EJECTING INTO THE CENTRAL AND NORTHERN PLAINS ON SUNDAY AND SHEARING OUT EARLY NEXT WEEK. THE ASSOCIATED SURFACE LOW FROM THIS TROUGH WILL HAVE A QUASI-STATIONARY FRONTAL BOUNDARY EXTENDING EASTWARD FROM IT SUNDAY AND MONDAY UNTIL THE BOUNDARY POTENTIALLY SHIFTS SOUTH OF THE AREA BY TUESDAY. THIS WILL HAVE AN IMPACT ON OUR SENSIBLE WEATHER CONDITIONS WITH RESPECT TO TEMPERATURES AND PRECIPITATION CHANCES. A DISTURBANCE RIDING OVER THE TOP OF THE MID/UPPER RIDGE OVER THE AREA COULD RESULT IN PRECIP CHANCES RETURNING LATE SATURDAY NIGHT INTO SUNDAY. THEN CONVERGENCE ALONG THE QUASI- STATIONARY FRONT AND ADDITIONAL WAVES EMANATING FROM THE WEAKENING TROUGH COULD BRING A FEW ADDITIONAL ROUNDS OF SHOWERS INTO MONDAY AND A FINAL WAVE NORTH OF THE SOUTHWARD SINKING FRONT ON TUESDAY. MAINTAINED CHANCE POPS FROM BLENDED INITIALIZATION. DESPITE SEVERAL PERIODS OF PRECIP CHANCES...IT DOES NOT APPEAR LIKELY TO BE A WASHOUT. THE BEST INSTABILITY AXIS WILL REMAIN PRIMARILY TO OUR SOUTH AND WEST...THOUGH OCCASIONAL ISOLATED THUNDERSTORMS ARE POSSIBLE IN THE SOUTHWESTERN 1/3 OR 1/4 OF THE CWA. THE POSITION OF THE FRONT WILL DETERMINE WHETHER MOST OR ALL OF THE LAKESHORE RECEIVES PERSISTENT ONSHORE FLOW LATER SUNDAY AND MONDAY...BUT AT LEAST THE IL SHORE WILL LIKELY BE MUCH COOLER THAN INLAND AREAS. AFTER TEMPERATURES LIKELY WELL INTO THE 60S AND EVEN 70S INLAND ON SUNDAY AND MONDAY...TEMPERATURES WILL COOL BACK TO SEASONABLE FOR LATE APRIL TUESDAY...AND EVEN COOLER FOR THE SHORE DUE TO ONSHORE WINDS. RODRIGUEZ/RC && .AVIATION... FOR THE 06Z TAFS... A STORM SYSTEM TO OUR WEST WILL LIFT A WARM FRONT NORTHWARD OVER THE TERMINALS BY THIS EVENING. THIS WILL LIKELY RESULT IN OUR BEST CHANCE FOR A PERIOD OF SHOWERS AND SOME THUNDERSTORMS OVER NORTHERN ILLINOIS/NORTHWESTERN INDIANA LATER TODAY INTO THIS EVENING. AS SUCH...I HAVE TWEAKED THE TIMING OF THE PRECIPITATION IN THE TAFS TO HIT THE LATE AFTERNOON THROUGH MID EVENING HOURS WITH SHOWERS. WE ALSO CANNOT RULE OUT SOME THUNDERSTORMS AS WELL WITH THIS BATCH OF SHOWERS...AS A MID-LEVEL DRY SLOT SHIFTING INTO THE REGION SHOULD HELP STEEPEN THE MID-LEVEL LAPSE RATES. AT THIS TIME I HAVE OPTED TO HOLD OFF INCLUDING THE THUNDER IN A TEMPO...BUT THE BEST CHANCES OF THUNDER WOULD LIKELY FALL IN THE CURRENT 00-03 UTC (22-01 UTC) TEMPO GROUPS AT THE EASTERN (KRFD) TAF SITES. WINDS THROUGH THE DAY WILL REMAIN EAST-SOUTHEASTERLY...AND AGAIN COULD BECOME A BIT GUSTY DURING THE DAY. AS THE WARM FRONT LIFTS NORTHWARD THIS EVENING THE WINDS SHOULD BECOME SOUTH-SOUTHWESTERLY. A PERIOD OF MVFR CIGS COULD ALSO ACCOMPANY THE WARM FRONTAL BOUNDARY. KJB && .MARINE... 324 PM CDT EAST-NORTHEAST WINDS OVER THE LAKE TODAY WILL TURN SOUTHEAST ON THE SOUTHERN PART OF THE LAKE ON WEDNESDAY AS A FRONTAL BOUNDARY LIFTS NORTH. EXPECT A PERIOD OF SOUTHERLY WINDS ON THURSDAY AS THE FRONT LIFTS FARTHER NORTH. BY THURSDAY NIGHT...A STRONGER COLD FRONT WILL PUSH SOUTH...RESULTING IN A PERIOD OF STRONGER NORTHERLY WINDS INTO FRIDAY. GUSTS WILL LIKELY BE IN THE 25-30 KT RANGE. THE NORTHERLY WINDS AND BUILDING WAVES WILL LIKELY NECESSITATE A SMALL CRAFT ADVISORY FRIDAY INTO FRIDAY EVENING FOR THE ILLINOIS AND INDIANA NEARSHORE WATERS. HIGH PRESSURE WILL BRING FAIRLY LIGHT WINDS FOR THE WHOLE LAKE ON SATURDAY. THEREAFTER...A QUASI-STATIONARY FRONT WILL EXTEND EAST FROM A SURFACE LOW OVER THE PLAINS SUNDAY AND MONDAY...WITH MOST OF THE OPEN WATER AREA LIKELY NORTH OF THE FRONT RESULTING IN MODERATE EASTERLY WINDS. DIRECTIONS COULD BE VARIABLE FOR THE NEARSHORE AND FAR SOUTHERN OPEN WATERS DEPENDING ON THE POSITION OF THE FRONT. THE FRONT WILL SAG WELL SOUTH OF THE LAKE ON TUESDAY...CAUSING NORTHEAST WINDS FOR THE WHOLE LAKE. RC && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 4 AM WEDNESDAY. && $$ 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 National Weather Service Lincoln IL 1130 PM CDT TUE APR 19 2016 .UPDATE... Issued at 827 PM CDT Tue Apr 19 2016 Convection over central Illinois since late afternoon has been most numerous just west of the Illinois River, with scattered thunderstorms and heavier rains at times. Showers have occurred as far east as Springfield, but this has been fading as of late. Overall trend in our forecast area has been for a decreasing trend over the last couple hours, with mainly light rains left from about Peoria-Springfield westward. Latest surface map showing the frontal boundary roughly along the I-72 corridor back into central Missouri where additional thunderstorms are occurring, and a gradual northward shift is expected later tonight. The current HRRR and earlier high- resolution NMM/ARW models have been significantly easing up on the precipitation this evening and are largely dry overnight. Have made some significant adjustments to the PoP trends to back off on the rain chances after midnight as a result. && .SHORT TERM...(Tonight) ISSUED AT 314 PM CDT Tue Apr 19 2016 Large upper level low over the western half of the country is not making much progress, nor is much eastern progression expected in the overnight. With some weak lift over the area and several weak boundaries in the vicinity...some rain chances cannot be ruled out around sunset in the west... as well as increasing slight chances after midnight for much of Central Illinois. At least initially tonight, the rainfall should remain scattered and more showery in nature. The deep low over the western half of the county has much of the northern half of IL and WI in a weak flow pattern as well...winds should remain somewhat light and variable through the overnight hours with some trend to southeasterly. Showers are expected to begin spreading in coverage at least after midnight...but confidence for any one location is small with the slowing system. .LONG TERM...(Wednesday through Tuesday) ISSUED AT 314 PM CDT Tue Apr 19 2016 Shorter range models are generally in agreement with their strength and timing of moving the closed upper low in the High Plains toward the mid-MS Valley by early Thursday. The GFS is a little quicker and a little farther south than the other models but overall their solutions are fairly similar, particularly the NAM and European. Scattered showers and isolated thunderstorms early Wed morning should give way to more widespread coverage of rainfall from later in the morning through the early evening. With deep moisture taking awhile to increase most of the rain accumulation will be on the lighter side. However, the best moisture, but with limited instability, will focus in the warm sector ahead of the cold front Wednesday afternoon into the evening. This will coincide with the highest PoPs and the vast majority of the QPF. Due to the limited instability will stick with isolated thunder through the shorter range. The upper level trough axis from the lifting upper level low is expected to pass through central IL early Thursday and eastern IL Thursday evening. This will bring a gradual end to the showers and isolated thunderstorms from west to east during the day Thursday. A secondary shortwave trough rotating through Great Lakes toward the upper Ohio Valley Friday could keep a few lingering showers south of I-70, otherwise a decreasing cloud trend and temperatures typical for later April in the mid-upper 60s can be expected. A piece of an upper level ridge over the western U.S. will flatten and get pushed east toward our region for early in the weekend. Dry weather with temperatures in the lower 70s can be expected on Saturday as a result. Things get a bit more complicated for Sunday into early next week as a series of vigorous upper level troughs move from the western U.S. toward the Plains and Midwest. In addition, a large upper trough in eastern Canada will move little, resulting in the approaching energy being sheared eastward across the Great Lakes. The resulting upper flow across area would be from the WSW, which means that frontal boundaries could lay out from west to east in the vicinity of Illinois. This would result in an unsettled period of weather with slightly warmer than normal temperatures by early next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1130 PM CDT Tue Apr 19 2016 Some lingering showers were west of KPIA but moving northwest, so general overnight theme will be for dry conditions and VFR ceilings generally above 9000 feet. Have even seen some fairly extensive clearing near KCMI which will result in ceilings scattering out at times. Frontal boundary roughly along a KUIN-KDNV line at 05Z will start to lift northward later tonight, with winds trending more southeast toward sunrise. Ceilings will be steadily decreasing after 12Z as an area of showers sweeps across central Illinois. Low VFR conditions expected to accompany these showers late morning and early afternoon. Additional showers and storms will advance out of Missouri in the afternoon ahead of a cold front, and have added VCTS mention to all TAF sites late afternoon and early evening. Ceilings expected to fall into MVFR range early afternoon ahead of the second area of showers/storms. Ceilings will rise in the evening immediately behind the passage of the front itself, with KPIA/KSPI most likely to see this before the end of the forecast period. && .ILX Watches/Warnings/Advisories... NONE. && $$ UPDATE...Geelhart SHORT TERM...HJS LONG TERM...Miller AVIATION...Geelhart Area Forecast Discussion National Weather Service Saint Louis MO 348 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 348 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
  [top] Area Forecast Discussion National Weather Service Springfield MO 302 AM CDT WED APR 20 2016 ...Chance of Showers Continues into Thursday then a Warmer Weekend... .SHORT TERM...(Today through Thursday) Issued at 250 AM CDT Wed Apr 20 2016 The upper level low that has been anchored out west the past few days will begin an eastward track the next couple of days as it opens up. A lead shortwave will lift north of the area today while a weak front pushes east across the area. Isolated to scattered showers will continue across the area today. However with the primary lifting mechanism tracking north of the area the potential for a widespread soaking rain is diminishing. The lack of instability will result in limited development of thunderstorms. The potential for a few showers will continue tonight and Thursday as the primary upper level trough axis makes its way across the region. Overall confidence in the short term forecast is high. .LONG TERM...(Thursday through Tuesday) Issued at 250 AM CDT Wed Apr 20 2016 A warming trend along with more sunshine will return Friday into the weekend in the wake of the exiting upper level trough. Upper level ridging and southerly winds will help to push high temperatures well into the 70s to near 80 degrees. A more active weather pattern will return next week as a series of disturbances track eastward across the region. However, forecast certainty of the details in regards to precipitation timing and coverage remain low. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overnight. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Lindenberg
  [top] Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 301 AM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1156 PM CDT TUE APR 19 2016 Rain is currently moving north and will have likely spread across all the west Missouri terminals by 1 AM. Current CIGs are in the MVFR range, though up stream obs show some IFR conditions under the heavier rain. Expect activity to persist through sunrise as a little surface low spins up and moves northeast Wednesday pushing the storms off to north while allow surface winds to continue veering around to the west by early afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Cutter
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1156 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1156 PM CDT TUE APR 19 2016 Rain is currently moving north and will have likely spread across all the west Missouri terminals by 1 AM. Current CIGs are in the MVFR range, though up stream obs show some IFR conditions under the heavier rain. Expect activity to persist through sunrise as a little surface low spins up and moves northeast Wednesday pushing the storms off to north while allow surface winds to continue veering around to the west by early afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...Cutter
Area Forecast Discussion National Weather Service Springfield MO 1150 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overinght. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Springfield MO 1150 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overinght. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 1149 PM CDT TUE APR 19 2016 .UPDATE... Issued at 939 PM CDT Tue Apr 19 2016 Area of rain/embedded thunderstorms should continue to slowly weaken and drift northward overnight tonight. Do not expect much if any in the way of activity after midnight tonight. Next round of at least scattered showers/storms will try and move north/northeast from south-central/southeast Missouri early Wednesday morning. Adjusted PoPs for the rest of tonight and also raised low temperatures a couple of degrees in most locations due to high dewpoints and clouds. Gosselin && .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated National Weather Service Saint Louis MO 941 PM CDT TUE APR 19 2016 .UPDATE... Issued at 939 PM CDT Tue Apr 19 2016 Area of rain/embedded thunderstorms should continue to slowly weaken and drift northward overnight tonight. Do not expect much if any in the way of activity after midnight tonight. Next round of at least scattered showers/storms will try and move north/northeast from south-central/southeast Missouri early Wednesday morning. Adjusted PoPs for the rest of tonight and also raised low temperatures a couple of degrees in most locations due to high dewpoints and clouds. Gosselin && .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 641 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 641 PM CDT TUE APR 19 2016 VFR conditions this evening are not expected to last as showers will move northeast across the region late tonight into Wednesday morning. Low end MVFR to IFR CIGs will spread across the terminals around midnight along with scattered showers that will persist until around sunrise Wednesday. Winds will veer around overnight to the south, southwest and finally west by Wednesday afternoon as the center of a small surface low, that brought the showers, moves northeast through northwest Missouri. CIgs will likely go back to VFR for the afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...Cutter
Area Forecast Discussion National Weather Service Springfield MO 600 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 557 PM CDT Tue Apr 19 2016 Pesky upper level low underneath blocking omega pattern still sitting off to the west. Scattered showers will remain in the terminals and mainly keeping in VCSH in the forecast. Main aviation concern again will be with the MVFR/IFR conditions. Will see ceilings lower again tonight, eventually into the IFR category at the 3 terminal locations. Conditions will improve during the day Wednesday, back into MVFR/VFR by late in the day. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 310 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...73
Area Forecast Discussion National Weather Service Springfield MO 243 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Frye
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 111 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more positively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 1234 PM CDT TUE APR 19 2016 ...18z Aviation Update... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Frye
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1222 PM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...73
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 558 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 12z TAFs through 12z Wednesday Morning) Issued at 549 AM CDT Tue Apr 19 2016 Band of light rain from near KCOU to KUIN will gradually dissipate this morning. Additional light showers and isolated thunderstorms are possible this afternoon...but sparse coverage precludes placing in TAFS. Ceilings will remain in the VFR category...with generally light and variable winds. Specifics for KSTL: Band of light rain this morning should stay west of KSTL metro...and ceilings will likely remain above 7000 feet for the duration of this TAF period. There is a chance for scattered showers and isolated thunderstorms this afternoon...but coverage is expected to remain sparse. Winds will remain light southwest to south. Browning && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 549 AM CDT TUE APR 19 2016 ...Update to Aviation Discussion for 12Z TAFS... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 543 AM CDT Tue Apr 19 2016 For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will continue at the KJLN TAF site early this morning, then will improve through the day. Ceilings may lower into the MVFR range at the KSGF and KBBG TAF sites this morning before improving this afternoon. Patchy fog will also occur early this morning, especially at the KBBG site. Showers should remain north and south of the TAF sites through this morning, then scattered showers will be possible this afternoon into tonight across the area. Ceilings are expected to lower into the MVFR to IFR range again tonight into early Wednesday morning. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Wise
Area Forecast Discussion National Weather Service Saint Louis MO 349 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1133 PM CDT Mon Apr 18 2016 Scattered showers will affect KCOU and possibly KUIN through the rest of tonight. Showers should be light and likely not pose visibility issues. For the metro terminals...showers should stay west. Ceilings will also lower at KCOU and KUIN into MVFR later on tonight. Some minor visibility reduction is also possible in fog at KCOU. For Tuesday...highest threat of showers/storms again from KCOU to KUIN with the best chance of convection during the late afternoon and early evening hours. Heavier showers/storms could dip visibilities down briefly into IFR. Metro terminals again likely too far to the east. Specifics for KSTL: Lion`s share of shower/thunderstorm activity expected to stay west of terminal through Tuesday night. However...scattered showers/storms are possible Tuesday afternoon/evening in particular. Continue to leave out prevailing group as chances look higher further to the west. Winds will remain light/variable before turning southeasterly again Tuesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 258 AM CDT TUE APR 19 2016 ...Good Chance for Showers Today through Wednesday... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1132 PM CDT Mon Apr 18 2016 Scattered light showers across the area this evening and have affected the terminal locations with some light rain. While showers will be in the vicinity of the aviation sites tonight and Tue morning, the main concern will be with MVFR and IFR conditions. Will see ceilings deteriorate overnight and may build down enough for visibilities to also be affected. Showers will again become more numerous late in the period as the upper level shortwave to the west slowly approaches. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1153 PM CDT MON APR 18 2016 .Discussion... Issued at 332 PM CDT MON APR 18 2016 Water vapor imagery and H5 heights indicate the extensive closed low still positioned over the inter-mountain west with cold front currently moving through eastern Nebraska and Kansas, extending down into the Texas panhandle. At the regional level, band of heavier precip has moved northeastward through the morning and early afternoon, gradually weakening with time as primary forcing remained north across Iowa. Scattered showers remain on the backside of the main band, and the HRRR has done a great job with the overall precip trend. With a few hundred joules of CAPE, might see an isolated thunderstorm or two with this scattered activity. Western half of the CWA should see a downward trend in activity towards evening. Another vorticity maxima will peel off from the main low late tonight into Tuesday morning. Cold front looks to stall across the region from southwest to northeast Missouri. Greater chances for precip will focus near this diffuse cold front and with 600-800 J/kg of CAPE forecast Tuesday afternoon, expect to see thunderstorm development by early afternoon. Showers and thunderstorms expected once again Wednesday in somewhat of a wash-rinse-repeat cycle. Upper low finally begins to eject into the Plains Tuesday night into Wednesday, eventually merging into the northern stream flow. As the trough passes to the north of the region, we could see a few more showers and thunderstorms into Thursday. Upper level ridging will build into the central conus as we head into the weekend, bringing warm temperatures and relatively quiet weather. The next system to watch will be a trough ejecting out of the central Rockies the beginning of the next work week. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...PMM Aviation...MJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1256 AM CDT WED APR 20 2016 .UPDATE... ISSUED AT 1249 AM CDT WED APR 20 2016 BASED ON SURFACE OBSERVATIONS...WEB CAMS...AND SHORT TERM HI RESOLUTION MODELS HAVE ISSUED A DENSE FOG ADVISORY FROM THE EASTERN EDGE OF THE FORECAST AREA...TURTLE MOUNTAINS AND JAMES RIVER VALLEY...TO THE MISSOURI RIVER BORDER COUNTIES. VISIBILITIES WERE DOWN BELOW A QUARTER MILE IN THE TIOGA TO STANLEY AREAS AND LESS THAN A MILE AT MINOT AND JAMESTOWN. OTHERWISE...HAVE RAISED OVERNIGHT LOWS THROUGH THE JAMES RIVER VALLEY A FEW DEGREES DUE TO DEW POINTS AND EXPECTED FOG AND LOW STRATUS...WHICH SHOULD PREVENT MUCH OF A TEMPERATURE DROP OVERNIGHT. UPDATE ISSUED AT 929 PM CDT TUE APR 19 2016 LOWERED MINIMUM TEMPERATURES OVERNIGHT IN THE SOUTHWEST SLIGHTLY AS QUITE A BIT OF CLEARING HAS OCCURRED THIS EVENING. MINOT AND JAMESTOWN OBSERVATIONS HAVE NOTED SOME PATCHY FOG IN THE PAST HOUR OR SO...THEREFORE DID INTRODUCE PATCHY FOG IN PARTS OF THE CENTRAL AND EAST EARLIER THAN ORIGINALLY ANTICIPATED. OTHER THAN THAT...THE FORECAST LOOKS TO BE ON TRACK. UPDATE ISSUED AT 640 PM CDT TUE APR 19 2016 FORECAST LOOKS MAINLY ON TRACK SO NO MAJOR CHANGES WERE NEEDED FOR THIS UPDATE. DID INCREASE PATCHY FOG TO AREAS OF FOG FROM 06Z TO 12Z OVERNIGHT EAST OF THE MISSOURI RIVER...REASONING BASED ON RECENT MOISTURE...SOUTHERLY FLOW...AND FORECAST LIGHT SURFACE WINDS. THE LAST SEVERAL ITERATIONS OF THE OPERATIONAL HRRR ALSO SEEM TO SUGGEST THIS SOLUTION. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 331 PM CDT TUE APR 19 2016 FOCUS IS ON THE EXITING UPPER LEVEL LOW OVER THE ROCKIES AND FOG WEDNESDAY MORNING. THE SEMI STATIONARY UPPER LEVEL LOW PRESSURE OVER THE ROCKIES IS BEGINNING TO PROPAGATE EAST...CUTTING OFF MOIST FLOW INTO THE NORTHERN PLAINS. ONLY A FEW SHOWERS REMAIN ACROSS SOUTHEAST PARTS OF NORTH DAKOTA AND WILL FURTHER DIMINISH THROUGH THE NIGHT. DRIER AIR OVER CENTRAL SOUTH DAKOTA AND SOUTH CENTRAL NORTH DAKOTA HAS USHERED IN SOME MOSTLY CLEAR SKIES. SHORT RANGE MODELS WERE HAVING A HARD TIME PICKING UP ON THIS FEATURE...THUS LEANED MORE ON LATEST SATELLITE FOR THE SHORT TERM SKY FORECAST. SHORT RANGE MODELS STILL DEVELOP FOG ACROSS MUCH OF CENTRAL AND WESTERN NORTH DAKOTA TONIGHT INTO WEDNESDAY MORNING. WITH THAT SAID HAVE LEFT PATCHY FOG IN FOR ALL OF CENTRAL AND WESTERN NORTH DAKOTA DUE TO LIGHT WINDS AND AMPLE MOISTURE FROM RECENT RAINS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 331 PM CDT TUE APR 19 2016 FOCUS IN THE LONG TERM IS ON THE CHANCES FOR PRECIPITATION SATURDAY NIGHT INTO EARLY NEXT WEEK. THE 12 UTC GUIDANCE CONTINUES TO SHOW AN UPPER LEVEL RIDGE BUILDING INTO THE NORTHERN PLAINS THURSDAY...USHERING IN DRY CONDITIONS THURSDAY THROUGH SATURDAY AFTERNOON. LONGER RANGE MODELS HAVE COME INTO BETTER AGREEMENT ON THE NEXT WEATHER MAKER FOR THE NORTHERN PLAINS. LIKE THIS PREVIOUS SYSTEM A CUT OFF UPPER LEVEL LOW WILL SET UP OVER THE ROCKIES WITH MOIST FLOW MOVING NORTH INTO NORTH DAKOTA. AT THIS TIME THE WEEKEND SYSTEM APPEARS TO BE MORE PROGRESSIVE THAN THIS PAST WET WEATHER MAKER. CHANCES RAIN AND EVEN POSSIBLY SNOW ON THE BACK SIDE START SATURDAY NIGHT AND LAST INTO TUESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY) ISSUED AT 1256 AM CDT WED APR 20 2016 LIFR/VLIFR CONDITIONS IN FOG AND STRATUS ARE EXPECTED AT KISN/KMOT/KJMS THE REMAINDER OF TONIGHT THROUGH THE 14-16 UTC TIME FRAME WEDNESDAY MORNING. FOG/STRATUS MAY ENCROACH UPON KBIS AFTER 09 UTC. KDIK IS EXPECTED TO REMAIN VFR FOR THE 06 UTC TAF CYCLE. && .BIS WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR NDZ001>005-009>013-017>023-025-034>037-045>048-050-051. && $$ UPDATE...JPM SHORT TERM...MM LONG TERM...MM AVIATION...ZH
AREA FORECAST DISCUSSION
NWS PORTLAND OR
934 PM PDT TUE APR 19 2016 .SYNOPSIS...AN UPPER LEVEL TROUGH WILL APPROACH FROM THE SOUTHWEST TONIGHT...BRINGING LOW CLOUDS AND PATCHY DENSE FOG TO THE COAST TONIGHT...AND SHOWERS WITH COOLER TEMPERATURES WEDNESDAY. THUNDERSTORMS AND SMALL HAIL ARE POSSIBLE WEDNESDAY AFTERNOON AND EVENING. ANOTHER UPPER LEVEL LOW WILL CONTINUE THE COOLING TREND THURSDAY AND FRIDAY WITH MORE SHOWERS. SEASONAL TEMPERATURES EXPECTED THIS WEEKEND AS ANOTHER TROUGH IMPACTS THE PACIFIC NORTHWEST. && .UPDATE...THE BIGGEST CHANGES MADE WITH THE EVENING UPDATE WAS THE ADDITION OF PATCHY DENSE FOG ALONG THE COAST TONIGHT AND THUNDERSTORMS WITH SMALL HAIL WEDNESDAY AFTERNOON/EVENING. BASED ON RECENT HRRR RUNS FORECAST VISIBILITIES COMBINED WITH USCG OBSERVATIONS LEAD TO THE ADDITION OF PATCHY DENSE FOG ALONG THE COAST TONIGHT. FOR WEDNESDAY...MODEL SOUNDINGS CONTINUE TO SHOW DECENT HAIL PARAMETERS ACROSS THE FORECAST AREA...WITH SBCAPE APPROACHING 1000 J/KG AND 0-5 KM BULK SHEAR AROUND 30 TO 35 KT IN THE INTERIOR VALLEY. HOWEVER...00Z NAM SOUNDINGS INDICATE CONVECTIVE TEMPS IN THE MID TO UPPER 80S WHICH WILL HELP LIMIT SURFACE BASED CONVECTION AND HAIL SIZE. NONETHELESS...ELEVATED CONVECTION REMAINS A CONCERN WITH SMALL HAIL POSSIBLE UNDER ANY THUNDERSTORMS THAT DO DEVELOP. OTHERWISE...THE CURRENT FORECAST LOOKS ON TRACK SO NO OTHER CHANGES WERE MADE. /64 && .AVIATION...STRATUS AND AREAS OF DENSE FOG HAVE DEVELOPED ALONG THE COAST...RESULTING IN LIFR CONDITIONS. EXPECT FOG OR LOW STRATUS TO REMAIN ALONG THE COAST THROUGH WED MORNING. INLAND AREAS WILL LIKELY REMAIN VFR TONIGHT WITH LIGHT WINDS. SYSTEM APPROACHING FROM THE S WILL BRING AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS WED...POSSIBLY AS EARLY AS WED MORNING S OF KEUG-KONP. SHOWER/TSTM CHANCES SPREAD N THROUGH THE DAY WED... WITH ABOUT A 40 PERCENT CHANCE OF TSRA DURING THE AFTERNOON. DECIDED TO HANDLE THIS WITH VCTS IN MOST TERMINALS AFTER 21Z WED FOR NOW...CAN FINE TUNE THE DETAILS WITH THE 12Z/18Z TAF PACKAGES. KPDX AND APPROACHES...VFR THROUGH TONIGHT UNDER VARIABLE HIGH CLOUDS. INCREASING CHANCE OF SHOWERS WEDNESDAY WITH A CHANCE OF THUNDERSTORMS WEDNESDAY AFTERNOON. WEAGLE/MCCOY && .MARINE...MAIN ISSUE FOR THE COASTAL WATERS WILL BE AREAS OF DENSE FOG TONIGHT...AS WEAK HIGH PRESSURE BUILDS ACROSS THE WATERS FOR LIGHT AND VARIABLE WINDS AND SEAS GENERALLY AROUND 5 FT. WEAK COLD FRONT LIFTS N-NE FROM THE NORCAL WATERS LATER TONIGHT AND WED... BRINGING AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS. IF THUNDERSTORMS DEVELOP...SOME COULD PRODUCE A DECENT AMOUNT OF LIGHTNING AS WELL AS GUSTY AND ERRATIC WINDS ON THE WATERS. OTHERWISE EXPECT A SLIGHT INCREASE IN S-SW WINDS...POSSIBLY GUSTING TO 15-20 KT AT TIMES LATER WED/WED NIGHT. SLIGHTLY STRONGER SOUTHERLIES SHOULD DEVELOP FRIDAY AS A SURFACE TROUGH AND WEAK FRONT APPROACHES THE COAST. SEAS WILL INCREASE SOME LATER IN THE WEEK. WEAGLE/SCHNEIDER && .PREVIOUS DISCUSSION /ISSUED 252 PM PDT TUE APR 19 2016/... SHORT TERM...TEMPERATURES ARE RAISING UNDER ABUNDANT SUNSHINE THIS AFTERNOON. INLAND AREAS WILL WARM INTO THE 80S LATE THIS AFTERNOON. CLOUDS HUGGING THE COAST WILL KEEP COASTAL AREAS FROM WARMING MUCH. THE NORTH COAST MAY GET INTO THE 70S...BUT THE CENTRAL OREGON COAST WILL LIKELY STAY IN THE 60S...OR EVEN UPPER 50S DOWN BY NEWPORT WHERE THE CLOUDS HAVE MADE MORE OF A PRESENCE. CONDITIONS BEGIN TO CHANGE TONIGHT AS AN UPPER LEVEL LOW CURRENTLY OFFSHORE OF NORTHERN CALIFORNIA MOVES NE TOWARDS OREGON. THIS WILL SPUR A SOUTHWEST MARINE PUSH THAT WILL REINFORCE LOW CLOUDS ALONG THE COAST...AND SPREAD COOLER MARINE AIR INTO THE SOUTH AND POSSIBLY CENTRAL WILLAMETTE VALLEY. THE APPROACHING TROUGH WILL DEEPEN THE MARINE LAYER ALLOWING THE COASTAL CLOUDS ALONG THE COAST TO PUSH INLAND ACROSS THE COASTAL AREAS AND INTO PARTS OF THE COAST RANGE EARLY WEDNESDAY MORNING. BESIDES THE LOW MARINE CLOUDS EXPECT MID AND HIGH LEVEL CLOUDS ASSOCIATED WITH THE UPPER TROUGH TO STREAM MOVE OVER THE REGION. THE HIGHER CLOUDS WILL MOVE SOUTH TO NORTH FROM WED MORNING THROUGH WEDNESDAY AFTERNOON. THE CLOUDIER SKIES AND INFLUENCE OF THE MARINE AIR WILL RESULT IN COOLER TEMPERATURES WEDNESDAY AFTERNOON...AROUND 8 TO 10 DEGREES COOLER THAN TODAY. ALTHOUGH IT WILL BE COOLER...THE FORECASTED TEMPERATURES ARE STILL AROUND 15 DEGREES WARMER THAN THE SEASONAL NORMALS. THE UPPER LEVEL TROUGH WILL INCREASE MOISTURE AT THE MID LEVELS PRIMING THE ATMOSPHERE FOR CONVECTION. THE AXIS OF THE NEGATIVELY-TILTED UPPER TROUGH WILL SWING OVER NW OREGON IN THE AFTERNOON DURING PEAK HEATING TIME. THIS WILL BE THE BEST CHANCE FOR THUNDERSTORMS TO DEVELOP...AND THERE DOES LOOK TO BE A DECENT CHANCE. DETERMINING THE LOCATION OF THUNDERSTORMS IS DIFFICULT...BUT THE WARMER SURFACE TEMPERATURES NORTH OF SALEM MAKES ME THINK THE BEST CHANCE FOR THUNDERSTORMS WILL BE THERE. HOWEVER...SOUNDINGS INDICATE THE CONVECTION MAY BE ELEVATED...AND THESE TYPE OF THUNDERSTORMS HAVE BEEN KNOWN TO SHOW UP IN AREAS WHERE THEY ARE LEAST EXPECTED. A CHANCE FOR SHOWERS WILL INCREASE SOUTH TO NORTH WEDNESDAY MORNING...AND LIKE THUNDERSTORMS...THE LOCATION AND TIMING OF THE SHOWERS ARE DIFFICULT TO FORECAST. CAN GENERALLY EXPECT 0.05 TO 0.10 INCH OF RAIN WITH THE SHOWERS...EXCEPT AROUND 0.2 INCH OVER THE CASCADES...AND WITH ANY THUNDERSTORMS THAT MAY DEVELOP. THE UPPER TROUGH WILL MOVE TO THE NE WED NIGHT AND SHOWERS WILL EASE. THE CHANCE FOR SHOWERS RETURNS THURSDAY AFTERNOON AS THE NEXT UPPER LOW APPROACHES. THIS LOW IS APPROACHING FROM THE NW AND WILL BRING ANOTHER NEGATIVELY UPPER TROUGH ACROSS THE PACIFIC NW THURSDAY AND FRIDAY. TEMPERATURES WILL CONTINUE THE DOWNWARD TREND...BUT STILL STAY ABOVE THE SEASONAL NORMALS. EXPECT SHOWERS THURSDAY AND FRIDAY WITH AROUND 0.10 TO 0.20 INCH OF RAIN EACH DAY. MOST OF THE CONVECTION WILL STAY NORTH AND EAST ON THURSDAY...BUT THERE IS A POSSIBILITY FOR THUNDERSTORMS FRIDAY AFTERNOON AS THE PARENT UPPER LOW MOVES INLAND ACROSS NORTHERN CALIFORNIA AND SOUTHERN OREGON. FORECAST CONFIDENCE IS LOW FOR NOW ON THE THREAT FOR THUNDERSTORMS...ESPECIALLY WITH THE EXPECTED CLOUD COVER AND COOLER TEMPERATURES...BUT CAN NOT IGNORE THE MODELED CAPE OF 300-500 J/KG...AND HAVE ADDED A SLIGHT CHANCE OF THUNDERSTORMS FOR THE CASCADES AND AREAS NORTH OF SALEM FRIDAY AFTERNOON. TJ LONG TERM...FRIDAY NIGHT THROUGH TUESDAY. AFTER A SPELL OF SUMMER WEATHER...APRIL RETURNS FOR THE WEEKEND WITH TEMPERATURES DROPPING BACK DOWN AROUND OR EVEN BELOW NORMAL. NORTHWESTERLY FLOW ALOFT WILL BRING BRING A SERIES OF SHORTWAVES INTO THE PACIFIC NORTHWEST OVER THE WEEKEND. MODERATE ONSHORE FLOW WITH OROGRAPHIC LIFT ALONG THE COAST RANGE AND CASCADES WILL KEEP SHOWERS IN THE AREA BETWEEN SYSTEMS ON SATURDAY. THE NEXT SYSTEM WILL BRING MORE WIDESPREAD SHOWERS ON SUNDAY. THE SUNDAY SYSTEM WILL BRING SNOW LEVELS DOWN BELOW THE PASSES...WHICH MEANS A FEW INCHES OF SNOW COULD FALL AT THE PASSES DURING THE DAY ON SUNDAY. SHORTWAVE RIDGING BUILDS JUST OFF THE COAST...AND DEPENDING ON HOW FAR NORTH IT BUILDS THIS WILL EITHER DRY US OUT OR REDUCE THE NUMBER OF SHOWERS ON MONDAY AND TUESDAY. KEPT A SLIGHT CHANCE OF SHOWERS ON THESE DAYS DUE TO THIS UNCERTAINTY. -MCCOY && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...NONE. && $$ INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/NWSPORTLAND WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS AMARILLO TX
410 AM CDT WED APR 20 2016 .DISCUSSION... TAKING ANOTHER LOOK AT THE LATEST HIGH-RES MODELS...THE HRRR IS NOW BACKING OFF FROM THE DEVELOPMENT OF DENSE FOG ACROSS THE PANHANDLES THIS MORNING. WILL LIKELY TO NEED TO CANCEL BUT WILL HOLD OFF UNTIL CLOSER TO DAYBREAK TO SEE IF ANY DENSE FOG DEVELOPS. IF NOT...WILL CANCEL BEFORE SHIFT CHANGE THIS MORNING. OTHERWISE...LOW CLOUDS WILL PREVAIL THIS MORNING AS THE VIGOROUS CLOSED UPPER LOW OVER THE CENTRAL PLAINS STATES ALLOWS FOR A VORT LOBE TO ROTATE NORTHWEST TO SOUTHEAST ON THE BASAL OF THE UPPER TROUGH BY 00Z TO 06Z THURSDAY ACROSS THE FORECAST AREA. CONVECTION SHOULD DEVELOP AFTER 20Z TO 22Z TODAY...MAINLY OVER THE SOUTHERN HALF OF THE TEXAS PANHANDLE...WITH THE SEVERE THREAT PRIMARILY ACROSS THE SOUTHEASTERN AND SOUTH CENTRAL PORTIONS OF THE TEXAS PANHANDLE LATER TODAY AND TONIGHT. CONVECTION SHOULD QUICKLY EXIT THE PANHANDLES BY 12Z THURSDAY AS AN UPPER RIDGE BUILDS IN FROM THE WEST LATE THIS WEEK. WARMER AND DRIER CONDITIONS EXPECTED THURSDAY THROUGH THE WEEKEND. THE MEDIUM RANGE MODELS DIFFER WITH RESPECT TO THE NEXT CLOSED UPPER LOW PROGGED TO MOVE OUT OF THE GREAT BASIN REGION THIS WEEKEND INTO EARLY NEXT WEEK. THE ECMWF...WHICH WAS THE DRIER MODEL 24 HOURS AGO...IS NOW FORECASTING AN OPEN WAVE TO TRACK NORTHEAST OUT OF BAJA CALIFORNIA AND NORTHWEST MEXICO FRIDAY NIGHT AND SATURDAY INTO SOUTHWEST TEXAS BY SATURDAY NIGHT AND SUNDAY. THE MAIN CLOSED UPPER LOW IS FORECAST TO LIFT EAST AND NORTH OUT OF THE GREAT BASIN REGION INTO THE CENTRAL ROCKIES AND NORTHERN PLAINS STATES BY EARLY NEXT WEEK. THE ECMWF BREAKS OUT QPF SATURDAY AFTERNOON ACROSS THE NORTHWESTERN PORTIONS OF THE FORECAST AREA SATURDAY AFTERNOON BUT KEEPS THE REMAINDER OF THE WEEKEND AND EARLY NEXT WEEK DRY. THE GFS IS COMPLETELY THE OPPOSITE OF 24 HOURS AGO AND IS NOW KEEPING THE CLOSED UPPER LOW OVER THE NORTHERN STREAM RATHER THAN THE SOUTHERN STREAM. THE GFS ALSO FORECASTS AN OPEN WAVE LIFTING NORTH AND EAST OUT BAJA CALIFORNIA AND NORTHWESTERN/NORTHERN MEXICO...HOWEVER THE GFS KEEPS THE QPF WELL SOUTH OF THE PANHANDLES AND...LIKE THE ECMWF...MAINTAINS A DRY FORECAST THROUGH THE END OF THE WEEKEND INTO EARLY NEXT WEEK. THEREFORE...OPTED TO REMOVE POPS FROM SUNDAY AND GO WITH A DRY AND UNSEASONABLY WARM FORECAST THIS WEEKEND INTO EARLY NEXT WEEK. BREEZY TO WINDY THIS WEEKEND AS A DEEPENING SURFACE TROUGH DEVELOPS TO THE LEE OF THE ROCKIES WHICH WILL THEN TRACK EAST INTO THE FORECAST AREA SUNDAY. A COLD FRONT IS FORECAST TO PUSH ACROSS THE PANHANDLES EARLY NEXT WEEK WITH NO CONVECTION ASSOCIATED WITH THE FRONT. SCHNEIDER && .FIRE WEATHER... A DEEPENING SURFACE TROUGH OVER EASTERN COLORADO OR WESTERN KANSAS SOUTHWARD TO NEAR THE TEXAS AND NEW MEXICO STATE LINE WILL TRACK EAST INTO THE TEXAS AND OKLAHOMA PANHANDLES ON SUNDAY. INCREASING DOWNSLOPING SOUTHWESTERLY 20 FOOT WINDS AND MINIMUM AFTERNOON HUMIDITIES FALLING INTO THE 15 TO 20 PERCENT RANGE ACROSS MAINLY THE WESTERN SECTIONS OF THE PANHANDLES COULD POSSIBLY RESULT IN ELEVATED FIRE WEATHER CONDITIONS SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING. SCHNEIDER && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 69 45 72 45 77 / 20 50 5 0 5 BEAVER OK 68 44 73 43 79 / 20 20 5 0 5 BOISE CITY OK 65 39 71 41 77 / 30 30 5 0 5 BORGER TX 70 46 75 47 79 / 20 50 5 0 5 BOYS RANCH TX 72 43 74 44 79 / 20 40 5 0 5 CANYON TX 71 44 73 44 77 / 20 40 5 0 0 CLARENDON TX 68 48 73 47 77 / 20 70 10 0 5 DALHART TX 67 41 72 42 77 / 30 40 5 0 5 GUYMON OK 67 42 73 43 79 / 20 20 5 0 5 HEREFORD TX 73 45 73 44 77 / 20 30 5 0 0 LIPSCOMB TX 69 46 74 44 78 / 10 30 5 0 5 PAMPA TX 67 45 70 46 77 / 20 60 10 0 5 SHAMROCK TX 69 49 74 46 78 / 20 70 10 0 5 WELLINGTON TX 70 51 76 47 79 / 20 70 10 0 5 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...DENSE FOG ADVISORY UNTIL 11 AM CDT THIS MORNING FOR THE FOLLOWING ZONES: ARMSTRONG...CARSON...COLLINGSWORTH... DALLAM...DEAF SMITH...DONLEY...GRAY...HANSFORD...HARTLEY... HEMPHILL...HUTCHINSON...LIPSCOMB...MOORE...OCHILTREE... OLDHAM...POTTER...RANDALL...ROBERTS...SHERMAN...WHEELER. OK...DENSE FOG ADVISORY UNTIL 11 AM CDT THIS MORNING FOR THE FOLLOWING ZONES: BEAVER...CIMARRON...TEXAS. && $$ 3/11
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
346 AM CDT WED APR 20 2016 .DISCUSSION... LATEST RADAR COMPOSITES SHOW MCS WORKING ACROSS NORTH CENTRAL TEXAS. IT HAS BECOME MORE EAST TO WEST ORIENTED OVERNIGHT. MESOSCALE MODELS...ICLUDING TTU WRF AND HRRR VERIFYING FAIRLY WELL ATTM. INTERESTING TO NOTE BOTH WEAKEN THIS SYSTEM AFTER SUNRISE AS OUTFLOW PUSHES SOUTH...WITH NEW CONVECTIVE DEVELOPMENT ALONG OUTFLOW...WITH SOME INCREASE IN AREAL COVERAGE IN THE AFTERNOON WITH DAYTIME HEATING. THINK THIS SCENARIO IS REASONABLE AND WILL LEAN THAT WAY WITH THE FORECAST...BRINGING INCREASING POPS THIS MORNING OVER NW ZONES...AND THEN INCREASING POPS MORE IN THE AFTERNOON FOR SOUTHEAST SECTIONS. WILL GO WITH LIKELY POPS FOR PEAK TIMES. MODEL TOTAL QPF FROM SYNOPTIC MODELS THROUGH THIS EVENING LOOKING AT GFS AND EC VARIES FROM HALF AN INCH TO 1.5 INCHES. HRRR STORM TOTALS SHOW TYPICAL VARIABILTY WITH CONVECTION...WITH ISOLD AMOUNTS 3 TO 4 INCHES. THINK MOST AREAS WILL SEE AN INCH OR LESS BUT WILL HAVE POTENTIAL FOR THOSE LOCALLY HIGHER 3 INCH AMOUNTS WHERE THE CELLS OCCUR. EVEN YDA WITH PULSE STORMS HAD A FEW VERY ISOLD HIGHER TOTALS. IMPACT ON RIVERS AND BAYOUS WHICH REACT MORE TO BASIN AVERAGE PRECIP SHOULD BE MINIMAL UNLESS THE HEAVIER LOCAL RAINS FALL IN THOSE SMALLER MORE SENSITIVE BASINS...OR OVER PLACES LIKE ADDICKS RESEVOIR. WILL HAVE TO MONITOR CLOSELY. GIVEN THE SATURATED SOILS AND ELEVATED FLOWS WILL KEEP FLASH FLOOD WATCH UP THROUGH TODAY FOR THOSE AREAS THAT HAD THE MOST INTENSE RAINFALL. COLD FRONT DROPS ACROSS THE AREA TOMORROW LIKELY BRINGING ANOTHER BAND OF SHOWERS AND THUNDERSTORMS THROUGH. THINKING AGAIN LOOKING AT ANOTHER INCH OR SO OF QPF ON AVERAGE WITH TWO DAY TOTALS OF 1 TO 3 INCHES ON AVERAGE BUT WITH LOCALLY HIGHER AMOUNTS. AFTER THIS FRONT PUSHES SOUTH OF THE AREA THURSDAY NIGHT...WILL SEE DRIER AIR FILTER INTO THE AREA FROM THE NORTH ON FRIDAY. SOME HINT IN GFS AND EC OF SOME LINGERING SHOWERS AT THE COAST ON FRIDAY BEFORE FRONT PUSHES OFF TO THE SOUTHEAST. LOOKS LIKE INCREASING AMOUNTS OF SUN AND LOWER HUMIDITY FOR FRIDAY...FROM NORTH TO SOUTH THROUGH THE DAY. AFTER NICE DRY DAY ON SATURDAY START TO SEE RETURN FLOW OFF THE GULF SATURDAY NIGHT. MODELS SHOWING WELL DEFINED UPPER DISTURBANCE CROSSING THE AREA ON MONDAY...LIKELY BRINGING MORE SHOWERS AND THUNDERSTORMS DURING THE SUNDAY AND MONDAY TIME FRAME. UPPER DISTURBANCE PUSHES EAST FOR TUESDAY WITH LESSENING RAIN CHANCES BUT REMAINING HUMID. SO...NOT A PROLONGUED DRY PERIOD THAT WOULD BE MORE IDEAL BUT REMAINING IN FAIRLY ACTIVE PATTERN AFTER A FEW WELCOME RELATIVELY DRY DAYS FRIDAY AND SATURDAY. 46 && .MARINE... LIGHT TO MODERATE ONSHORE WINDS ALONG WITH PERIODS OF SHOWERS AND THUNDERSTORMS WILL PERSIST UNTIL LATE THURSDAY NIGHT OR EARLY FRIDAY MORNING WHEN A COLD FRONT MOVES THROUGH THE AREA. LIGHT TO MODERATE OFFSHORE WINDS BEHIND THE FRONT WILL PERSIST THROUGH EARLY SATURDAY. LIGHT ONSHORE WINDS THAT RETURN TO THE AREA SATURDAY NIGHT AND STRENGTHEN ON SUNDAY AND MONDAY ARE EXPECTED TO PERSIST THROUGH ALL OF NEXT WEEK. 42 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 78 67 79 60 79 / 70 30 60 30 10 HOUSTON (IAH) 78 67 81 64 81 / 70 40 70 30 10 GALVESTON (GLS) 77 70 79 68 78 / 50 50 60 30 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... LIBERTY...MONTGOMERY...POLK...SAN JACINTO...WALKER... WALLER...WASHINGTON...WHARTON. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1145 PM CDT TUE APR 19 2016 .AVIATION... SINKING MOTION ACROSS TAFS SO FAR TONIGHT BEHIND THE CONVECTIVE SYSTEM ALONG A COLD FRONT NOW SOUTH OF THE AREA. LOW LEVEL FLOW ALSO DIVERGENT...BUT EXPECTED TO TURN MORE NORTHEAST TO EASTERLY LATER TONIGHT. LOWER ATMOSPHERE QUITE MOIST SO SHOULD NOT BE DIFFICULT TO SATURATE...ESPECIALLY WITH A MORE PRONOUNCED UPSLOPE COMPONENT AT BOTH KPVW AND KLBB. CURRENT EXPECTATIONS ARE FOR LIFR CEILINGS DEVELOPING AND POSSIBLE WE COULD SEE AT LEAST A BRIEF PERIOD OF VERY LOW VISIBILITIES BUT CANNOT STATE WITH MUCH CONFIDENCE JUST WHEN THAT MAY OCCUR. BUT SOMETHING TO WATCH FOR LATER. LOW CEILINGS LIKELY TO HOLD THROUGH WEDNESDAY MORNING AND MAY ONCE MORE SEE PATCHY DRIZZLE AT SOME POINT. THEN CEILINGS SHOULD BEGIN LIFTING LATE WEDNESDAY MORNING INTO THE AFTERNOON TO MVFR LEVELS AND SCATTERING OUT BOTH KLBB AND KPVW BUT MAY HOLD AT KCDS MUCH OF THE DAY. ANOTHER UPPER TROUGH WILL DRIVE SOUTHEAST FROM COLORADO ACROSS THE TEXAS PANHANDLE WEDNESDAY EVENING SPREADING THUNDER CHANCES ESPECIALLY TOWARDS KCDS WHERE INITIAL PROB30 HAS BEEN INSERTED. THUNDER CHANCES ALSO KPVW AND KLBB MAINLY LATER TOMORROW NIGHT. RMCQUEEN && .PREV DISCUSSION... /ISSUED 651 PM CDT TUE APR 19 2016/ AVIATION... IN SIMILAR FASHION TO THIS MORNING...VFR CONDITIONS ARE LIKELY TO CRATER TO IFR AT PVW AND LBB AFTER MIDNIGHT AS THE LOWER ATMOSPHERE REMAINS VERY MOIST. COULD SEE DENSE FOG ALSO DEVELOP THOUGH THIS IS LESS LIKELY COMPARED TO JUST VERY LOW STRATUS. CONFIDENCE IN IFR AT CDS IS LESS CERTAIN AS SOME MODELS ARE RELUCTANT TO REDEVELOP LOW CLOUDS...BUT HAVE HINTED AT THIS SCENARIO WITH A SCATTERED LOW LAYER. SHOULD SEE VFR RETURN TO LBB AND PVW BY THE AFTN AT WHICH POINT A REPEAT OF AFTERNOON TS ARE POSSIBLE SOUTH OF AN UPPER LOW...MAINLY N OF LBB. PREV DISCUSSION... /ISSUED 318 PM CDT TUE APR 19 2016/ SHORT TERM... PRECIP CHANCES WILL CONTINUE TO BE THE FOCUS TONIGHT AND AGAIN WEDNESDAY. ONGOING SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS BEGINNING TO MARCH EWD ACROSS THE NRN HALF OF THE FCST AREA AT A PRETTY GOOD CLIP. THE SOURCE REGION FOR CONVECTIVE REDEVELOPMENT THAT HAD BEEN ANCHORED IN ERN NM IS SHIFTING TO THE WRN SOUTH PLAINS. THIS ADJUSTMENT OCCURRING IN RESPONSE TO THE MAIN UPPER TROUGH OVER NRN NM SHOWING EWD MOVEMENT PER WATER VAPOR IMAGERY THE LAST COUPLE HOURS. TROUGH AXIS SHOULD SHIFT TO THE EAST OF THE FCST AREA AROUND 06Z WITH HIGH CHANCE TO LIKELY POPS ERN HALF OF THE FCST AREA APPROPRIATE UNTIL THEN. COULD ALSO SEE A SHIFT SWD WITH THE CONVECTION AS OUTFLOW INTERACTS WITH LOW LEVEL MOISTURE SRN SOUTH AND ROLLING PLAINS PER HRRR OUTPUT. FOCUS THEN SHIFTS TO PRECIP CHANCE WEDNESDAY. APPEARS A DECENTLY DEFINED DRYLINE WILL SHIFT INTO THE WRN ZONES DURING THE AFTN. LOW LEVEL MOISTURE TO REMAIN IN PLACE TO ITS EAST WITH SFC DEW POINT TEMPS UPPER 40S-LOWER 50S. NOT MUCH UPPER SUPPORT EVIDENT WITH A SHORT WAVE TROUGH PROGGED TO SEWD THROUGH THE MEAN FLOW FROM SRN COLORADO TWD THE PANHANDLE. WEAKLY FORCED CONVECTIVE INITIATION POSSIBLE LATE AFTN JUST EAST OF THE DRYLINE GENERALLY ALONG I-27. ONLY OTHER ISSUE IS CHANCE FOR FOG AROUND SUNRISE. COOL...MOIST AIR MASS WITH UPSLOPE EASTERLY LOW LEVEL FLOW POINT TO THE POSSIBILITY. NO CONSENSUS FROM GUIDANCE ATTM. WILL KEEP MENTION OUT FOR NOW AND LET NEXT SHIFT REEVALUATE. LONG TERM... A SECONDARY COLD FRONT WILL PUSH THROUGH TOMORROW NIGHT AS A SHORT WAVE ROTATES AROUND THE BACKSIDE OF THE MUCH LARGER UPPER LEVEL LOW ACROSS THE MIDWEST. WITH PLENTY OF MOISTURE IN PLACE AS WELL AS LIFT FROM THE SHORTWAVE A COMPLEX OF SHOWERS AND THUNDERSTORMS WILL BE HIGHLY POSSIBLE ACROSS THE EASTERN TX PANHANDLE AND ROLLING PLAINS. WHILE SOME HEAVY RAIN WILL BE POSSIBLE AS PWATS WILL BE OVER 1 INCH THE COMPLEX SHOULD MOVE QUICK ENOUGH TO HELP MITIGATE FLOODING CONCERNS. WINDS WILL REMAIN OUT OF THE NORTHEAST INTO LATE THURSDAY NIGHT WHICH WILL HELP KEEP TEMPS INTO THE LOW 70S. WINDS WILL TURN BACK TO THE SOUTH/SOUTHEAST BY EARLY FRIDAY AFTERNOON AS A LEE TROF DEVELOPS. THIS...IN ADDITION TO AN UPPER RIDGE MOVING OVER THE REGION...WILL ALLOW TEMPS TO WARM BACK TO NEAR AVERAGE FRIDAY. TEMPS WILL CONTINUE TO WARM TO SEVERAL DEGREES ABOVE AVERAGE BY SUNDAY AS WINDS WILL CONTINUOUSLY STAY OUT OF THE SOUTH TO SOUTHWEST. THE LEE TROF WILL PUSH SOUTHWARD STARTING LATE SUNDAY MORNING ALLOWING A DRYLINE TO PUSH EASTWARD FROM NM. A SMALL CHANCE EXISTS FOR ISOLATED THUNDERSTORMS ALONG THE DRYLINE...MOSTLY OVER THE ROLLING PLAINS...SUNDAY BUT WILL BE DEPENDENT ON THE TIMING OF A PASSING SHORTWAVE. WINDS WILL BE FAIRLY BREEZY...SPECIFICALLY ACROSS OUR NORTHWESTERN COUNTIES...BEHIND THE DRYLINE AS THE MID TO LOWER LEVELS DRY AND THERMAL PROFILES BECOME SUPER ADIABATIC. CONDITIONS BEYOND LATE SUNDAY BECOME QUESTIONABLE AS MODELS BEGIN TO DIVERGE WITH THE UPPER LEVEL PATTERN. THE ECMWF BRINGS AN UPPER LEVEL LOW CLOSE TO THE REGION BY MONDAY AFTERNOON/EVENING WHICH WOULD ALLOW WINDS TO KEEP BLOWING WHILE THE GFS TAKES A MORE PACIFIST ROLE BY KEEPING FLOW MOSTLY ZONAL AND DELAYING THE APPROACH OF THE LOW UNTIL EARLY WEDNESDAY. EITHER WAY THE FORECAST LOOKS TO REMAIN DRY. && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/05
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
641 AM CDT WED APR 20 2016 .SHORT TERM... 329 AM CDT THROUGH TONIGHT... THIS AFTERNOON AND EVENING WILL BRING THE HIGHEST CHANCE FOR SHOWERS IN THE FORECAST AREA IN TEN DAYS. WE HAVE KEPT THE MAIN THEME OF RAIN TIMING BEING MID- AFTERNOON THROUGH EVENING SPREADING FROM WEST TO EAST AND JUST REFINING THAT TO THE HOURLY LEVEL. DID INCREASE THE THUNDER POTENTIAL SOME OVER THE ILLINOIS PART OF THE CWA THOUGH THE RISK FOR SEVERE WEATHER REMAINS QUITE LOW. THE PERSISTENT LARGE UPPER LOW IS GYRATING ITS WAY SLOWLY EAST THIS MORNING WITH ITS CENTER NOW OVER THE CENTRAL PLAINS. A 90 KT UPPER JET ROUNDING THE SOUTHERN EDGE OF THIS CENTER AND ASSOCIATED DEEP PV ANOMALY THIS MORNING WILL HELP RE-DEEPEN THE LOW CENTER BY THIS EVENING OVER IOWA. UPPER FORCING AND ASSOCIATED LIFT IN ADVANCE OF THIS...ALONG WITH A LOW-LEVEL RESPONSE OF THETA-E ADVECTION...WILL SPREAD OVER ILLINOIS DURING THE AFTERNOON. GIVEN THIS WILL BE DURING THE PEAK HEATING TIME...EXPECT THAT THERE WILL BE AN INCREASE IN SHOWER AND STORM ACTIVITY...LIKELY JUST WEST OF THE CWA ALONG THE SYSTEM COLD FRONT DURING THE EARLY TO MID AFTERNOON AND SPREADING EAST FROM THERE. CONVECTIVE ALLOWING MODELS SUCH AS THE HRRR INDICATE THIS INCREASE AND TIMING...THOUGH HAVE VARIED QUITE A BIT FROM RUN-TO-RUN ON THE COVERAGE. A FEW THINGS COULD INDEED LIMIT AFTERNOON SHOWER/STORM COVERAGE SUCH AS THE NARROW NATURE OF THE DEEP MOIST PLUME WRAPPING NORTHWARD INTO THIS SYSTEM. OVERALL THOUGH EXPECT THE AFOREMENTIONED FORCING JUST AHEAD OF THE SYSTEM DRY SLOT TO BE ENOUGH TO PROVIDE AN UPTICK IN SHOWERS DURING THE AFTERNOON INTO EARLY EVENING...WARRANTING LIKELY WORDING IN THE FORECAST. THE INSTABILITY MAGNITUDES /A FEW HUNDRED J/KG/ ARE BETTER FOR THUNDER THAN PREVIOUS FORECAST CYCLES...MAINLY FOR THE NORTH CENTRAL ILLINOIS PART OF THE FORECAST AREA. THE TIMING OF THE MAIN SHOWER AND POSSIBLE THUNDERSTORM AREAS APPEAR TO BE EARLY ENOUGH TO PREVENT DEEPER INSTABILITY RETURN TO LEVELS THAT WOULD WARRANT A THREAT FOR SEVERE STORMS...THOUGH A FEW STRONG ONES WITH MAYBE SOME SMALL HAIL ARE POSSIBLE INTO THE WESTERN CWA WITH FREEZING LEVELS A LITTLE BELOW 10KFT. IN TERMS OF TEMPERATURES...THE FRONTAL BOUNDARY WHICH BROUGHT A 30 DEGREE TEMPERATURE GRADIENT ACROSS THE CWA YESTERDAY...IS NOW DRAPED OVER CENTRAL ILLINOIS TO SOUTHERN INDIANA. THIS WILL LIFT NORTHWARD AS A WARM FRONT TODAY. THE FRONTAL PROGRESSION WILL PROBABLY NOT BE FAR AHEAD OF RAIN SHOWER ACTIVITY WHICH MAKES THE TEMPERATURE FORECAST CHALLENGING. NORTHERN AREAS WILL CERTAINLY BE WARMER THAN YESTERDAY BUT HOW MUCH SO WILL DEPEND ON THE FRONTAL PASSAGE TIMING. ONSHORE FLOW A GOOD PART OF THE DAY FROM CHICAGO NORTHWARD WILL KEEP LAKESIDE TEMPERATURES COOLER AGAIN. FAR SOUTHERN AREAS HAVE THE CHANCE AGAIN TO REACH UPPER 70S. AS THE SYSTEM DRY SLOT WORKS OVERHEAD LATE THIS EVENING INTO OVERNIGHT...THE SHOWER ACTIVITY WILL PUSH NORTHEAST. THE LOW-LEVEL COOL ADVECTION WILL ACTUALLY WEAKEN GIVEN THE OVERALL OCCLUDED NATURE OF THIS SYSTEM...SO LOWS LOOK TO REMAIN IN THE 50S AREAWIDE. MTF && .LONG TERM... 329 AM CDT THURSDAY THROUGH TUESDAY... THE PRIMARY UPPER LOW WILL GRADUALLY TRANSITION INTO AN OPEN WAVE THROUGH THURSDAY AND THURSDAY NIGHT AND SHOULD DO SO AS IT TRACKS EASTWARD OVER THE FORECAST AREA. WHILE DRY AIR ALOFT WILL PREVENT MUCH FOR SHOWERS THURSDAY MORNING...MOST MODEL GUIDANCE INDICATES THE FORECAST AREA TO BE IN A FAVORABLE AREA OF UPPER SUPPORT TO AT LEAST SEE AFTERNOON AND EARLY EVENING SCATTERED SHOWERS AND EVEN A FEW STORMS AGAIN. WITH TEMPERATURES THURSDAY AFTERNOON WARMING BACK INTO THE MID 60S TO LOW 70S...THERE SHOULD BE A FEW HUNDRED J/KG OF CAPE TO WORK WITH. LOWER FREEZING LEVELS COULD PROVIDE A FEW SMALL HAIL PRODUCERS. BEHIND THIS TROUGH FRIDAY AND SATURDAY CONTINUE TO LOOK DRY. STOUT NORTHEAST WINDS ON FRIDAY WILL KEEP LAKESHORE HIGHS INCLUDING DOWNTOWN CHICAGO LIKELY SHY OF 50 DEGREES. INLAND AREAS ARE PRESENTLY FORECAST FOR HIGHS IN THE UPPER 50S/LOWER 60S...ALTHOUGH THIS WILL DEPEND ON CLOUDS CLEARING FRIDAY MORNING. GIVEN THE PRESENT AMPLIFIED/SEMI-BLOCKED PATTERN ACROSS THE EASTERN PACIFIC AND CONUS...CONFIDENCE IN THE LONGER TERM PATTERN EVOLUTION REMAINS LOW. A MASSIVE UPPER LOW/TROUGH IS EXPECTED ACROSS EASTERN CANADA AND THIS WILL PROVIDE NORTHWEST FLOW INTO THE GREAT LAKES...WHILE AN UPPER LOW OVER THE SOUTHWEST U.S. IS ANTICIPATED TO SLOWLY WORK ITS WAY EAST. TOGETHER THESE SHOULD DEVELOP A WEST-TO-EAST BAROCLINIC ZONE ACROSS THE MIDWEST THOUGH WHERE AND HOW ACTIVE REMAINS HIGHLY UNCERTAIN ON MODELS. THIS ALSO LEADS TO LOW CONFIDENCE IN TEMPERATURE FORECASTS AS A LARGE RANGE IS LIKELY ACROSS THIS BOUNDARY. RIGHT NOW HAVE FAVORED A BLEND OF THE EC/GFS/GEM...WHICH BRINGS THE BOUNDARY INTO THE AREA MONDAY AND JUST SOUTH BY TUESDAY. MTF && .AVIATION... FOR THE 12Z TAFS... A STORM SYSTEM TO OUR WEST WILL LIFT A WARM FRONT NORTHWARD OVER THE TERMINALS THIS EVENING. THIS WILL LIKELY RESULT IN OUR BEST CHANCE FOR A PERIOD OF SHOWERS AND THUNDERSTORMS OVER NORTHERN ILLINOIS/NORTHWESTERN INDIANA LATER TODAY INTO THIS EVENING. AS SUCH...I HAVE CONTINUED TO FOCUS THE PRECIPITATION IN THE TAFS TO HIT THE LATE AFTERNOON THROUGH EVENING HOURS WITH SHOWERS. WE STILL CANNOT RULE OUT SOME THUNDERSTORMS DIRECTLY IMPACTING THE TERMINALS AS WELL WITH THIS BATCH OF SHOWERS...AS A MID-LEVEL DRY SLOT SHIFTING INTO THE REGION SHOULD HELP STEEPEN THE MID-LEVEL LAPSE RATES. HOWEVER...WE STILL DONT HAVE HIGH ENOUGH CONFIDENCE ON THE EXACT TIMING TO PLACE IN A TEMPO GROUP AT THIS TIME. WINDS THROUGH THE DAY WILL REMAIN EAST-SOUTHEASTERLY...AND AGAIN COULD BECOME A BIT GUSTY DURING THE DAY. AS THE WARM FRONT LIFTS NORTHWARD THIS EVENING THE WINDS SHOULD BECOME SOUTH-SOUTHWESTERLY. A PERIOD OF LOWER END MVFR/IFR CIGS MAY ALSO DEVELOP OVERNIGHT TONIGHT FOLLOWING THE SHOWER ACTIVITY. CONFIDENCE ON THE EXTENT OF THESE LOWER CIGS IS LOW AT THIS TIME...BUT ANY LOWER CIGS WOULD IMPROVE QUICKLY THURSDAY MORNING. KJB && .MARINE... 228 AM CDT A WEAK AREA OF LOW PRESSURE IS EXPECTED TO MOVE EASTWARD OVER LAKE MICHIGAN ON THURSDAY. AS THIS LOW MOVES OVER THE LAKE...LIGHT WINDS AND A MOIST AIR MASS COULD PRODUCE A PERIOD OF FOG OVER THE LAKE. HOWEVER...NORTHERLY WINDS ARE EXPECTED TO INCREASE FROM NORTH TO SOUTH OVER THE LAKE THURSDAY NIGHT INTO FRIDAY FOLLOWING THE EASTWARD PASSAGE OF THE SURFACE LOW. THIS SHOULD RESULT IN A PERIOD OF 30 KT NORTHERLY WINDS ON FRIDAY BEFORE WINDS ABATE FRIDAY NIGHT AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS OVER THE UPPER GREAT LAKES. LARGE WIND WAVES...LIKELY IN EXCESS OF 5 FEET ON SOUTHERN LAKE MICHIGAN WILL RESULT IN OUR NEXT PERIOD OF SMALL CRAFT ADVISORY CONDITIONS FOR THE ILLINOIS AND INDIANA NEAR SHORE WATERS. OVER THE WEEKEND ANOTHER COLD FRONT IS EXPECTED TO SHIFT SOUTHWARD DOWN LAKE MICHIGAN. THERE IS STILL UNCERTAINTY ON THE EXACT TIMING OF THIS FRONT. HOWEVER...THERE ARE INDICATIONS THAT ANOTHER PERIOD OF STRONGER NORTH-NORTHEASTERLY WINDS WILL SET UP OVER THE LAKE POSSIBLY BY LATE SUNDAY OR MONDAY. THIS WILL BE ANOTHER PERIOD TO WATCH FOR POSSIBLE SMALL CRAFT CONDITIONS ON THE NEAR SHORE WATERS DUE TO WINDS AND HIGH WAVES. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 621 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 12z TAFs through 12z Thursday Morning) Issued at 612 AM CDT Wed Apr 20 2016 Area of MVFR ceilings from left over convection to our west last night will continue to spread east and lift throughout the morning. Forecasting the cloud base at VFR level by the time it reaches St. Louis Metro later this afternoon. This may be too optomistic and will need to be monitored. Otherwise...some scattered showers and thunderstorms are expected to develop this afternoon across mainly eastern Missouri and Illinois. Some potential for fog tonight if sky can clear and wind decreases. Specifics for KSTL: Light showers will impact terminal the next few hours with a better chance of showers and thunderstorms developing this afternoon. MVFR ceilings to the southwest are expected to lift to VFR level by the time they advect over the terminal. Could see some fog develop late tonight if sky can clear and wind decreases. CVKING && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
  [top] Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 620 AM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 12Z TAFS through 12Z Thursday Morning) Issued at 620 AM CDT WED APR 20 2016 Surface low over northeast KS will track into southeast NE over the next couple of hours, taking most rainfall with it and also bringing winds around from the southwest. This wind shift will enter far western MO between 8 AM and 9 AM. A few scattered showers possible through the morning, otherwise slowly improving conditions with clouds becoming scattered VFR later this morning and afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 620 AM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 12Z TAFS through 12Z Thursday Morning) Issued at 620 AM CDT WED APR 20 2016 Surface low over northeast KS will track into southeast NE over the next couple of hours, taking most rainfall with it and also bringing winds around from the southwest. This wind shift will enter far western MO between 8 AM and 9 AM. A few scattered showers possible through the morning, otherwise slowly improving conditions with clouds becoming scattered VFR later this morning and afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
  [top] Area Forecast Discussion National Weather Service Springfield MO 558 AM CDT WED APR 20 2016 ...Update to Aviation Discussion for 12Z TAFS... .SHORT TERM...(Today through Thursday) Issued at 250 AM CDT Wed Apr 20 2016 The upper level low that has been anchored out west the past few days will begin an eastward track the next couple of days as it opens up. A lead shortwave will lift north of the area today while a weak front pushes east across the area. Isolated to scattered showers will continue across the area today. However with the primary lifting mechanism tracking north of the area the potential for a widespread soaking rain is diminishing. The lack of instability will result in limited development of thunderstorms. The potential for a few showers will continue tonight and Thursday as the primary upper level trough axis makes its way across the region. Overall confidence in the short term forecast is high. .LONG TERM...(Thursday through Tuesday) Issued at 250 AM CDT Wed Apr 20 2016 A warming trend along with more sunshine will return Friday into the weekend in the wake of the exiting upper level trough. Upper level ridging and southerly winds will help to push high temperatures well into the 70s to near 80 degrees. A more active weather pattern will return next week as a series of disturbances track eastward across the region. However, forecast certainty of the details in regards to precipitation timing and coverage remain low. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 557 AM CDT Wed Apr 20 2016 For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will occur early this morning and gradually improve this morning with VFR conditions expected by this afternoon. Fog will also impact the KBBG TAF site early this morning. A cold front will spread east across the area later this morning. A few showers will be possible along the front, but the better chances for rain will be to the north of the area, so left rain out of the TAFS. Winds will be out of the southeast ahead of the front with winds becoming westerly behind the front this afternoon. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Wise
Area Forecast Discussion National Weather Service Saint Louis MO 348 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 348 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 302 AM CDT WED APR 20 2016 ...Chance of Showers Continues into Thursday then a Warmer Weekend... .SHORT TERM...(Today through Thursday) Issued at 250 AM CDT Wed Apr 20 2016 The upper level low that has been anchored out west the past few days will begin an eastward track the next couple of days as it opens up. A lead shortwave will lift north of the area today while a weak front pushes east across the area. Isolated to scattered showers will continue across the area today. However with the primary lifting mechanism tracking north of the area the potential for a widespread soaking rain is diminishing. The lack of instability will result in limited development of thunderstorms. The potential for a few showers will continue tonight and Thursday as the primary upper level trough axis makes its way across the region. Overall confidence in the short term forecast is high. .LONG TERM...(Thursday through Tuesday) Issued at 250 AM CDT Wed Apr 20 2016 A warming trend along with more sunshine will return Friday into the weekend in the wake of the exiting upper level trough. Upper level ridging and southerly winds will help to push high temperatures well into the 70s to near 80 degrees. A more active weather pattern will return next week as a series of disturbances track eastward across the region. However, forecast certainty of the details in regards to precipitation timing and coverage remain low. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overnight. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 301 AM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1156 PM CDT TUE APR 19 2016 Rain is currently moving north and will have likely spread across all the west Missouri terminals by 1 AM. Current CIGs are in the MVFR range, though up stream obs show some IFR conditions under the heavier rain. Expect activity to persist through sunrise as a little surface low spins up and moves northeast Wednesday pushing the storms off to north while allow surface winds to continue veering around to the west by early afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Cutter
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1156 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1156 PM CDT TUE APR 19 2016 Rain is currently moving north and will have likely spread across all the west Missouri terminals by 1 AM. Current CIGs are in the MVFR range, though up stream obs show some IFR conditions under the heavier rain. Expect activity to persist through sunrise as a little surface low spins up and moves northeast Wednesday pushing the storms off to north while allow surface winds to continue veering around to the west by early afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...Cutter
Area Forecast Discussion National Weather Service Springfield MO 1150 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overinght. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Springfield MO 1150 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overinght. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 1149 PM CDT TUE APR 19 2016 .UPDATE... Issued at 939 PM CDT Tue Apr 19 2016 Area of rain/embedded thunderstorms should continue to slowly weaken and drift northward overnight tonight. Do not expect much if any in the way of activity after midnight tonight. Next round of at least scattered showers/storms will try and move north/northeast from south-central/southeast Missouri early Wednesday morning. Adjusted PoPs for the rest of tonight and also raised low temperatures a couple of degrees in most locations due to high dewpoints and clouds. Gosselin && .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated National Weather Service Saint Louis MO 941 PM CDT TUE APR 19 2016 .UPDATE... Issued at 939 PM CDT Tue Apr 19 2016 Area of rain/embedded thunderstorms should continue to slowly weaken and drift northward overnight tonight. Do not expect much if any in the way of activity after midnight tonight. Next round of at least scattered showers/storms will try and move north/northeast from south-central/southeast Missouri early Wednesday morning. Adjusted PoPs for the rest of tonight and also raised low temperatures a couple of degrees in most locations due to high dewpoints and clouds. Gosselin && .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 641 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 641 PM CDT TUE APR 19 2016 VFR conditions this evening are not expected to last as showers will move northeast across the region late tonight into Wednesday morning. Low end MVFR to IFR CIGs will spread across the terminals around midnight along with scattered showers that will persist until around sunrise Wednesday. Winds will veer around overnight to the south, southwest and finally west by Wednesday afternoon as the center of a small surface low, that brought the showers, moves northeast through northwest Missouri. CIgs will likely go back to VFR for the afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...Cutter
Area Forecast Discussion National Weather Service Springfield MO 600 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 557 PM CDT Tue Apr 19 2016 Pesky upper level low underneath blocking omega pattern still sitting off to the west. Scattered showers will remain in the terminals and mainly keeping in VCSH in the forecast. Main aviation concern again will be with the MVFR/IFR conditions. Will see ceilings lower again tonight, eventually into the IFR category at the 3 terminal locations. Conditions will improve during the day Wednesday, back into MVFR/VFR by late in the day. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 310 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...73
Area Forecast Discussion National Weather Service Springfield MO 243 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Frye
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 111 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more positively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 1234 PM CDT TUE APR 19 2016 ...18z Aviation Update... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Frye
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1222 PM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...73
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 558 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 12z TAFs through 12z Wednesday Morning) Issued at 549 AM CDT Tue Apr 19 2016 Band of light rain from near KCOU to KUIN will gradually dissipate this morning. Additional light showers and isolated thunderstorms are possible this afternoon...but sparse coverage precludes placing in TAFS. Ceilings will remain in the VFR category...with generally light and variable winds. Specifics for KSTL: Band of light rain this morning should stay west of KSTL metro...and ceilings will likely remain above 7000 feet for the duration of this TAF period. There is a chance for scattered showers and isolated thunderstorms this afternoon...but coverage is expected to remain sparse. Winds will remain light southwest to south. Browning && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 549 AM CDT TUE APR 19 2016 ...Update to Aviation Discussion for 12Z TAFS... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 543 AM CDT Tue Apr 19 2016 For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will continue at the KJLN TAF site early this morning, then will improve through the day. Ceilings may lower into the MVFR range at the KSGF and KBBG TAF sites this morning before improving this afternoon. Patchy fog will also occur early this morning, especially at the KBBG site. Showers should remain north and south of the TAF sites through this morning, then scattered showers will be possible this afternoon into tonight across the area. Ceilings are expected to lower into the MVFR to IFR range again tonight into early Wednesday morning. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Wise
Area Forecast Discussion National Weather Service Saint Louis MO 349 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1133 PM CDT Mon Apr 18 2016 Scattered showers will affect KCOU and possibly KUIN through the rest of tonight. Showers should be light and likely not pose visibility issues. For the metro terminals...showers should stay west. Ceilings will also lower at KCOU and KUIN into MVFR later on tonight. Some minor visibility reduction is also possible in fog at KCOU. For Tuesday...highest threat of showers/storms again from KCOU to KUIN with the best chance of convection during the late afternoon and early evening hours. Heavier showers/storms could dip visibilities down briefly into IFR. Metro terminals again likely too far to the east. Specifics for KSTL: Lion`s share of shower/thunderstorm activity expected to stay west of terminal through Tuesday night. However...scattered showers/storms are possible Tuesday afternoon/evening in particular. Continue to leave out prevailing group as chances look higher further to the west. Winds will remain light/variable before turning southeasterly again Tuesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 258 AM CDT TUE APR 19 2016 ...Good Chance for Showers Today through Wednesday... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1132 PM CDT Mon Apr 18 2016 Scattered light showers across the area this evening and have affected the terminal locations with some light rain. While showers will be in the vicinity of the aviation sites tonight and Tue morning, the main concern will be with MVFR and IFR conditions. Will see ceilings deteriorate overnight and may build down enough for visibilities to also be affected. Showers will again become more numerous late in the period as the upper level shortwave to the west slowly approaches. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1153 PM CDT MON APR 18 2016 .Discussion... Issued at 332 PM CDT MON APR 18 2016 Water vapor imagery and H5 heights indicate the extensive closed low still positioned over the inter-mountain west with cold front currently moving through eastern Nebraska and Kansas, extending down into the Texas panhandle. At the regional level, band of heavier precip has moved northeastward through the morning and early afternoon, gradually weakening with time as primary forcing remained north across Iowa. Scattered showers remain on the backside of the main band, and the HRRR has done a great job with the overall precip trend. With a few hundred joules of CAPE, might see an isolated thunderstorm or two with this scattered activity. Western half of the CWA should see a downward trend in activity towards evening. Another vorticity maxima will peel off from the main low late tonight into Tuesday morning. Cold front looks to stall across the region from southwest to northeast Missouri. Greater chances for precip will focus near this diffuse cold front and with 600-800 J/kg of CAPE forecast Tuesday afternoon, expect to see thunderstorm development by early afternoon. Showers and thunderstorms expected once again Wednesday in somewhat of a wash-rinse-repeat cycle. Upper low finally begins to eject into the Plains Tuesday night into Wednesday, eventually merging into the northern stream flow. As the trough passes to the north of the region, we could see a few more showers and thunderstorms into Thursday. Upper level ridging will build into the central conus as we head into the weekend, bringing warm temperatures and relatively quiet weather. The next system to watch will be a trough ejecting out of the central Rockies the beginning of the next work week. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...PMM Aviation...MJ
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1018 AM CDT WED APR 20 2016 .DISCUSSION... WEAKENING LINE OF STORMS WAS PUSHING INTO POLK...SAN JACINTO... MONTGOMERY...HARRIS...FORT BEND...AND COLORADO COUNTIES AT 10 AM. LIGHT RAIN WAS OCCURRING BEHIND THE SYSTEM. THE NAM12 HAS HAD A DECENT HANDLE ON EVENTS SO FAR...AND THE MODEL CLEARS THE SYSTEM OUT BY THE EARLY AFTERNOON. THE RAP AND TEXAS TECH BOTH SHOW SOME SCATTERED REDEVELOPMENT IS POSSIBLE DURING THE MID AND LATE AFTERNOON PERIOD. TRIMMED POPS DOWNWARD FOR THIS AFTERNOON TO ACCOUNT FOR THE LESSENING RAIN CHANCES IN THE MODEL. THE 12Z SOUNDINGS AT KLCH AND KCRP BOTH HAD A PW OF 1.5/1.6 INCHES. RAINFALL AMOUNTS FROM THE RAIN GAUGE NETWORK WITH THE SYSTEM HAS BEEN UNDER A HALF AN INCH...WHILE RADAR HAS SHOWN SOME LOCALIZED 1 INCH TOTALS. THIS POTENTIAL WILL LINGER OVER THE CENTRAL AND COASTAL COUNTIES AHEAD OF THE LINE IN THE FLASH FLOOD WATCH AREA. BECAUSE OF THE LESS EXPECTED COVERAGE IN THE NORTH... HAVE TAKEN OUT WALKER...GRIMES...BRAZOS...AND BURLESON COUNTIES FROM THE FLASH FLOOD WATCH. THE WATCH STILL GOES THROUGH 7 PM THIS EVENING FOR THE REMAINING COUNTIES...AND WILL MAKE A DECISION LATER THIS AFTERNOON ON WHETHER OR NOT TO EXTEND THE WATCH. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 79 67 77 57 79 / 60 30 50 30 10 HOUSTON (IAH) 79 67 80 64 81 / 60 40 70 40 10 GALVESTON (GLS) 75 70 76 69 76 / 50 30 50 30 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...CHAMBERS...COLORADO...FORT BEND...GALVESTON...HARRIS...LIBERTY...MONTGOMERY...POLK... SAN JACINTO...WALLER...WASHINGTON...WHARTON. GM...NONE. && $$ DISCUSSION...40 AVIATION/MARINE...47
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
924 AM CDT WED APR 20 2016 .UPDATE... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ALONG AND BEHIND AN OUTFLOW BOUNDARY PUSHING ALONG HIGHWAY 90. A WEAK COLD FRONT IS SLOWLY PUSHING ACROSS THE NORTHERN HILL COUNTRY PER LATEST SURFACE OBSERVATIONS AND SPC MESOSCALE ANALYSIS PAGE. THIS ACTIVITY IS EXPECTED TO CONTINUE THROUGH THE AFTERNOON AS IT SHIFTS TO THE SOUTH AND EAST. BOTH HRRR AND RAP 13 MODELS SHOW A DOWNWARD TREND ON THE SHOWER AND THUNDERSTORM ACTIVITY FOR THE SHORT TERM/FIRST PERIOD. LATEST KEWX RADAR LOOPS SHOW A DECREASE IN THE INTENSITY OF SHOWERS AND STORMS. NEW STORMS DEVELOPMENT ARE POSSIBLE ACROSS THE SOUTHERN EDWARDS PLATEAU AND THE RIO GRANDE AREAS THIS AFTERNOON AS THE TAIL END OF THE WEAK COLD FRONT PUSHES TO THE SOUTH AS IT MEETS WITH THE PASSAGE OF AN UPPER SHORT WAVE. FLASH FLOOD WATCH CONTINUES IN EFFECT THROUGH 1 PM THIS AFTERNOON FOR THE EASTERN COUNTIES OF SOUTH CENTRAL TEXAS (MORE DETAILS ON THIS IN THE WATCHES/WARNINGS/ADVISORIES SECTION). NEW RAINFALL AMOUNTS(NEXT 3 TO 6 HOURS)THROUGH THIS AFTERNOON COULD RANGE FROM 1 TO 2 INCHES ACCORDING TO KEWX DOPPLER RADAR ESTIMATES AND REFLECTIVITY TRENDS. && .PREV DISCUSSION... /ISSUED 611 AM CDT WED APR 20 2016/ AVIATION... WEAKENING COMPLEX OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE TO TREK SOUTHWARD. WILL BEGIN TAFAUS FOR THE FIRST FEW HOURS WITH -RA PREVAILING BUT WILL TEMPO -TSRA TO COVER THE THREAT FOR THE ISOLATED THUNDERSTORMS. FOR THE SAN ANTONIO SITES...WILL ONLY MENTION VCSH LATER THIS MORNING AS CONFIDENCE IS A BIT LESS THIS SYSTEM MAKES IT THIS FAR SOUTH. CEILINGS ARE PRESENTLY AROUND LOW MVFR OR IFR AND THESE RESTRICTIONS SHOULD REMAIN IN PLACE THROUGH THE EARLY AFTERNOON. ANOTHER ROUND OF MVFR IS EXPECTED TOMORROW NIGHT. BEYOND THIS MORNING...CANT RULE OUT ADDITIONAL ISOLATED OR SCATTERED PRECIPITATION...BUT CHANCES ARE TOO LOW TO MENTION IN THE TAFS AT THIS TIME. PREV DISCUSSION... /ISSUED 359 AM CDT WED APR 20 2016/ SHORT TERM (TODAY THROUGH THURSDAY)... SHOWERS AND THUNDERSTORMS ALONG A WACO TO SAN ANGELO TO BIG LAKE LINE WERE MOVING TO THE SOUTHEAST AT 25 MPH. THE LINE WILL MOVE INTO LLANO AND BURNET COUNTIES BY 5 AM AND THEN SLOW AS IT MOVES FURTHER INTO SOUTH CENTRAL TEXAS. THE LINE/BOUNDARY STALLS ACROSS SOUTH CENTRAL TEXAS LATER TODAY...MOST LIKELY AROUND THE I-10 CORRIDOR. RAINFALL AMOUNTS UP TO 1 TO 2 INCHES ARE POSSIBLE. THIS RAINFALL WILL NOT CAUSE MUCH FLOOD THREAT FOR MOST AREAS. HAVE MAINTAINED THE FLASH FLOOD WATCH EAST OF I-35 THROUGH MIDDAY TODAY AS ANY ADDITIONAL RAIN WILL CAUSE NEW OR AGGRAVATE ONGOING FLOODING IN THOSE AREAS THAT HAVE RECEIVED COPIOUS AMOUNTS OF RAIN SINCE SUNDAY. THERE IS A POTENTIAL THE WATCH COULD BE EXTENDED. LOCALLY HEAVY DOWNPOURS ARE POSSIBLE ALONG AND NEAR THE BOUNDARY THIS AFTERNOON INTO EVENING AND AGAIN ON THURSDAY. CAPES AVERAGING AROUND 2500 J/KG AND 0-6KM SHEAR OF 25 TO 35 KTS INDICATE A MARGINAL RISK OF STRONG TO SEVERE STORMS DURING THE AFTERNOON INTO EARLY EVENING HOURS TODAY AND THURSDAY. HAIL AND STRONG WIND GUSTS ARE THE MAIN THREATS. LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)... THE PESKY UPPER LEVEL LOW OPENS INTO TROUGH ALONG THE MISSISSIPPI VALLEY THURSDAY NIGHT SENDING A WEAK COLD FRONT ACROSS SOUTH CENTRAL TEXAS. SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE FRONT. RIDGING AT THE SURFACE AND ALOFT IS INDICATED FRIDAY AND SATURDAY. THE AIRMASS DRIES AND STABILIZES ACROSS MOST OF SOUTH CENTRAL TEXAS. HOWEVER...A MOIST SOUTHEASTERLY FLOW UP THE RIO GRANDE WILL MAINTAIN LOW CHANCES OF RAIN THERE ON FRIDAY AND SATURDAY. A COMPACT UPPER LEVEL TROUGH DEVELOPS OVER NORTHWESTERN MEXICO ON SATURDAY AND MOVES ACROSS TEXAS ON SUNDAY INTO EARLY MONDAY BRINGING RAIN CHANCES. A FEW MODELS SHOW LOCALLY HEAVY DOWNPOURS. RAIN CHANCES RETURN THE MIDDLE OF NEXT WEEK AS ANOTHER UPPER LEVEL TROUGH TAKES SHAPE OVER THE WESTERN STATES WITH A PACIFIC FRONT/DRYLINE MOVING INTO OUR AREA. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 79 65 80 61 80 / 60 30 40 30 10 AUSTIN BERGSTROM INTL AIRPORT 79 64 79 60 79 / 60 30 40 30 10 NEW BRAUNFELS MUNI AIRPORT 80 64 80 62 80 / 50 30 40 40 10 BURNET MUNI AIRPORT 78 63 77 57 77 / 60 30 40 20 10 DEL RIO INTL AIRPORT 83 66 85 63 82 / 20 20 30 30 20 GEORGETOWN MUNI AIRPORT 79 63 77 58 78 / 60 30 50 20 10 HONDO MUNI AIRPORT 81 65 82 62 81 / 30 30 40 40 10 SAN MARCOS MUNI AIRPORT 78 64 79 61 79 / 50 30 40 40 10 LA GRANGE - FAYETTE REGIONAL 79 66 79 62 80 / 60 30 50 40 10 SAN ANTONIO INTL AIRPORT 80 66 80 63 80 / 40 30 40 40 10 STINSON MUNI AIRPORT 82 66 82 64 81 / 40 30 40 40 10 && .EWX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 1 PM CDT THIS AFTERNOON FOR THE FOLLOWING COUNTIES: BASTROP...CALDWELL...DE WITT...FAYETTE...GONZALES... LAVACA...LEE. && $$ MESOSCALE/AVIATION...26 SYNOPTIC/GRIDS...17 PUBLIC SERVICE/DATA COLLECTION...TREADWAY
AREA FORECAST DISCUSSION
NWS AMARILLO TX
648 AM CDT WED APR 20 2016 .AVIATION... MVFR TO IFR CEILINGS EXPECTED TO PERSIST THIS MORNING. LIGHT TO MODERATE SOUTHWEST LOW-LEVEL WINDS EXPECTED TO DEVELOP...BOOSTING DRYING AND DISSIPATION/LIFTING OF LOW CLOUDS. CUMULUS CLOUDS EXPECTED TO DEVELOP THIS AFTERNOON. SCATTERED THUNDERSTORMS EXPECTED TO DEVELOP AFTER 21Z TODAY AS VORTICITY MAXIMUM ARRIVES FROM NORTHWEST. WEAK COLD FRONT WILL SUPPORT THUNDERSTORM DEVELOPMENT THROUGH THE EVENING. DRIER AND MORE STABLE AIR MOVES IN LATE TONIGHT...WITH CLEARING EXPECTED. COCKRELL && .PREV DISCUSSION... /ISSUED 410 AM CDT WED APR 20 2016/ DISCUSSION... TAKING ANOTHER LOOK AT THE LATEST HIGH-RES MODELS...THE HRRR IS NOW BACKING OFF FROM THE DEVELOPMENT OF DENSE FOG ACROSS THE PANHANDLES THIS MORNING. WILL LIKELY TO NEED TO CANCEL BUT WILL HOLD OFF UNTIL CLOSER TO DAYBREAK TO SEE IF ANY DENSE FOG DEVELOPS. IF NOT...WILL CANCEL BEFORE SHIFT CHANGE THIS MORNING. OTHERWISE...LOW CLOUDS WILL PREVAIL THIS MORNING AS THE VIGOROUS CLOSED UPPER LOW OVER THE CENTRAL PLAINS STATES ALLOWS FOR A VORT LOBE TO ROTATE NORTHWEST TO SOUTHEAST ON THE BASAL OF THE UPPER TROUGH BY 00Z TO 06Z THURSDAY ACROSS THE FORECAST AREA. CONVECTION SHOULD DEVELOP AFTER 20Z TO 22Z TODAY...MAINLY OVER THE SOUTHERN HALF OF THE TEXAS PANHANDLE...WITH THE SEVERE THREAT PRIMARILY ACROSS THE SOUTHEASTERN AND SOUTH CENTRAL PORTIONS OF THE TEXAS PANHANDLE LATER TODAY AND TONIGHT. CONVECTION SHOULD QUICKLY EXIT THE PANHANDLES BY 12Z THURSDAY AS AN UPPER RIDGE BUILDS IN FROM THE WEST LATE THIS WEEK. WARMER AND DRIER CONDITIONS EXPECTED THURSDAY THROUGH THE WEEKEND. THE MEDIUM RANGE MODELS DIFFER WITH RESPECT TO THE NEXT CLOSED UPPER LOW PROGGED TO MOVE OUT OF THE GREAT BASIN REGION THIS WEEKEND INTO EARLY NEXT WEEK. THE ECMWF...WHICH WAS THE DRIER MODEL 24 HOURS AGO...IS NOW FORECASTING AN OPEN WAVE TO TRACK NORTHEAST OUT OF BAJA CALIFORNIA AND NORTHWEST MEXICO FRIDAY NIGHT AND SATURDAY INTO SOUTHWEST TEXAS BY SATURDAY NIGHT AND SUNDAY. THE MAIN CLOSED UPPER LOW IS FORECAST TO LIFT EAST AND NORTH OUT OF THE GREAT BASIN REGION INTO THE CENTRAL ROCKIES AND NORTHERN PLAINS STATES BY EARLY NEXT WEEK. THE ECMWF BREAKS OUT QPF SATURDAY AFTERNOON ACROSS THE NORTHWESTERN PORTIONS OF THE FORECAST AREA SATURDAY AFTERNOON BUT KEEPS THE REMAINDER OF THE WEEKEND AND EARLY NEXT WEEK DRY. THE GFS IS COMPLETELY THE OPPOSITE OF 24 HOURS AGO AND IS NOW KEEPING THE CLOSED UPPER LOW OVER THE NORTHERN STREAM RATHER THAN THE SOUTHERN STREAM. THE GFS ALSO FORECASTS AN OPEN WAVE LIFTING NORTH AND EAST OUT BAJA CALIFORNIA AND NORTHWESTERN/NORTHERN MEXICO...HOWEVER THE GFS KEEPS THE QPF WELL SOUTH OF THE PANHANDLES AND...LIKE THE ECMWF...MAINTAINS A DRY FORECAST THROUGH THE END OF THE WEEKEND INTO EARLY NEXT WEEK. THEREFORE...OPTED TO REMOVE POPS FROM SUNDAY AND GO WITH A DRY AND UNSEASONABLY WARM FORECAST THIS WEEKEND INTO EARLY NEXT WEEK. BREEZY TO WINDY THIS WEEKEND AS A DEEPENING SURFACE TROUGH DEVELOPS TO THE LEE OF THE ROCKIES WHICH WILL THEN TRACK EAST INTO THE FORECAST AREA SUNDAY. A COLD FRONT IS FORECAST TO PUSH ACROSS THE PANHANDLES EARLY NEXT WEEK WITH NO CONVECTION ASSOCIATED WITH THE FRONT. SCHNEIDER FIRE WEATHER... A DEEPENING SURFACE TROUGH OVER EASTERN COLORADO OR WESTERN KANSAS SOUTHWARD TO NEAR THE TEXAS AND NEW MEXICO STATE LINE WILL TRACK EAST INTO THE TEXAS AND OKLAHOMA PANHANDLES ON SUNDAY. INCREASING DOWNSLOPING SOUTHWESTERLY 20 FOOT WINDS AND MINIMUM AFTERNOON HUMIDITIES FALLING INTO THE 15 TO 20 PERCENT RANGE ACROSS MAINLY THE WESTERN SECTIONS OF THE PANHANDLES COULD POSSIBLY RESULT IN ELEVATED FIRE WEATHER CONDITIONS SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING. SCHNEIDER PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 69 45 72 45 77 / 20 50 5 0 5 BEAVER OK 68 44 73 43 79 / 20 20 5 0 5 BOISE CITY OK 65 39 71 41 77 / 30 30 5 0 5 BORGER TX 70 46 75 47 79 / 20 50 5 0 5 BOYS RANCH TX 72 43 74 44 79 / 20 40 5 0 5 CANYON TX 71 44 73 44 77 / 20 40 5 0 0 CLARENDON TX 68 48 73 47 77 / 20 70 10 0 5 DALHART TX 67 41 72 42 77 / 30 40 5 0 5 GUYMON OK 67 42 73 43 79 / 20 20 5 0 5 HEREFORD TX 73 45 73 44 77 / 20 30 5 0 0 LIPSCOMB TX 69 46 74 44 78 / 10 30 5 0 5 PAMPA TX 67 45 70 46 77 / 20 60 10 0 5 SHAMROCK TX 69 49 74 46 78 / 20 70 10 0 5 WELLINGTON TX 70 51 76 47 79 / 20 70 10 0 5 && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 69 45 72 45 77 / 20 50 5 0 5 BEAVER OK 68 44 73 43 79 / 20 20 5 0 5 BOISE CITY OK 65 39 71 41 77 / 30 30 5 0 5 BORGER TX 70 46 75 47 79 / 20 50 5 0 5 BOYS RANCH TX 72 43 74 44 79 / 20 40 5 0 5 CANYON TX 71 44 73 44 77 / 20 40 5 0 0 CLARENDON TX 68 48 73 47 77 / 20 70 10 0 5 DALHART TX 67 41 72 42 77 / 30 40 5 0 5 GUYMON OK 67 42 73 43 79 / 20 20 5 0 5 HEREFORD TX 73 45 73 44 77 / 20 30 5 0 0 LIPSCOMB TX 69 46 74 44 78 / 10 30 5 0 5 PAMPA TX 67 45 70 46 77 / 20 60 10 0 5 SHAMROCK TX 69 49 74 46 78 / 20 70 10 0 5 WELLINGTON TX 70 51 76 47 79 / 20 70 10 0 5 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 03/11
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
642 AM CDT WED APR 20 2016 .AVIATION... SCATTERED SHRA ARE DEVELOPING ACROSS THE AREA AS A LINE OF GENERALLY WEAKENING SHRA/TSRA BEGINS MOVING INTO OUR NORTHERN AND WESTERN SECTIONS. MOST TAF SITES ARE GOING WITH VCSH TEMPO TSRA AS THIS ACTIVITY SPREADS ACROSS THE AREA THIS MORNING THROUGH EARLY THIS AFTERNOON. BOUNDARIES FROM THESE STORMS MIGHT END UP HELPING TO FIRE ADDITIONAL STORM DEVELOPMENT IN THE MID AFTERNOON THROUGH EARLY EVENING HOURS FROM ROUGHLY IAH SOUTHWARD... BUT HARD TO PINPOINT EXACTLY WHERE THIS MIGHT SET UP. FOR LATER TODAY...JUST GOING WITH VCSH UP NORTH AND VCTS DOWN SOUTH. GENERALLY EXPECT TO SEE LOTS OF MVFR CEILINGS THROUGHOUT THE DAY. SHOULD SEE A BREAK IN STORM ACTIVITY TONIGHT AS CEILINGS LOWER TO MVFR/IFR LEVELS FOLLOWED BY MORE SHRA/TSRA DURING THE DAY TOMORROW. 42 && .PREV DISCUSSION... /ISSUED 346 AM CDT WED APR 20 2016/ DISCUSSION... LATEST RADAR COMPOSITES SHOW MCS WORKING ACROSS NORTH CENTRAL TEXAS. IT HAS BECOME MORE EAST TO WEST ORIENTED OVERNIGHT. MESOSCALE MODELS...INCLUDING TTU WRF AND HRRR VERIFYING FAIRLY WELL ATTM. INTERESTING TO NOTE BOTH WEAKEN THIS SYSTEM AFTER SUNRISE AS OUTFLOW PUSHES SOUTH...WITH NEW CONVECTIVE DEVELOPMENT ALONG OUTFLOW...WITH SOME INCREASE IN AREAL COVERAGE IN THE AFTERNOON WITH DAYTIME HEATING. THINK THIS SCENARIO IS REASONABLE AND WILL LEAN THAT WAY WITH THE FORECAST...BRINGING INCREASING POPS THIS MORNING OVER NW ZONES...AND THEN INCREASING POPS MORE IN THE AFTERNOON FOR SOUTHEAST SECTIONS. WILL GO WITH LIKELY POPS FOR PEAK TIMES. MODEL TOTAL QPF FROM SYNOPTIC MODELS THROUGH THIS EVENING LOOKING AT GFS AND EC VARIES FROM HALF AN INCH TO 1.5 INCHES. HRRR STORM TOTALS SHOW TYPICAL VARIABILTY WITH CONVECTION...WITH ISOLD AMOUNTS 3 TO 4 INCHES. THINK MOST AREAS WILL SEE AN INCH OR LESS BUT WILL HAVE POTENTIAL FOR THOSE LOCALLY HIGHER 3 INCH AMOUNTS WHERE THE CELLS OCCUR. EVEN YDA WITH PULSE STORMS HAD A FEW VERY ISOLD HIGHER TOTALS. IMPACT ON RIVERS AND BAYOUS WHICH REACT MORE TO BASIN AVERAGE PRECIP SHOULD BE MINIMAL UNLESS THE HEAVIER LOCAL RAINS FALL IN THOSE SMALLER MORE SENSITIVE BASINS...OR OVER PLACES LIKE ADDICKS RESERVOIR. WILL HAVE TO MONITOR CLOSELY. GIVEN THE SATURATED SOILS AND ELEVATED FLOWS WILL KEEP FLASH FLOOD WATCH UP THROUGH TODAY FOR THOSE AREAS THAT HAD THE MOST INTENSE RAINFALL. COLD FRONT DROPS ACROSS THE AREA TOMORROW LIKELY BRINGING ANOTHER BAND OF SHOWERS AND THUNDERSTORMS THROUGH. THINKING AGAIN LOOKING AT ANOTHER INCH OR SO OF QPF ON AVERAGE WITH TWO DAY TOTALS OF 1 TO 3 INCHES ON AVERAGE BUT WITH LOCALLY HIGHER AMOUNTS. AFTER THIS FRONT PUSHES SOUTH OF THE AREA THURSDAY NIGHT...WILL SEE DRIER AIR FILTER INTO THE AREA FROM THE NORTH ON FRIDAY. SOME HINT IN GFS AND EC OF SOME LINGERING SHOWERS AT THE COAST ON FRIDAY BEFORE FRONT PUSHES OFF TO THE SOUTHEAST. LOOKS LIKE INCREASING AMOUNTS OF SUN AND LOWER HUMIDITY FOR FRIDAY...FROM NORTH TO SOUTH THROUGH THE DAY. AFTER NICE DRY DAY ON SATURDAY START TO SEE RETURN FLOW OFF THE GULF SATURDAY NIGHT. MODELS SHOWING WELL DEFINED UPPER DISTURBANCE CROSSING THE AREA ON MONDAY...LIKELY BRINGING MORE SHOWERS AND THUNDERSTORMS DURING THE SUNDAY AND MONDAY TIME FRAME. UPPER DISTURBANCE PUSHES EAST FOR TUESDAY WITH LESSENING RAIN CHANCES BUT REMAINING HUMID. SO...NOT A PROLONGED DRY PERIOD THAT WOULD BE MORE IDEAL BUT REMAINING IN FAIRLY ACTIVE PATTERN AFTER A FEW WELCOME RELATIVELY DRY DAYS FRIDAY AND SATURDAY. 46 MARINE... LIGHT TO MODERATE ONSHORE WINDS ALONG WITH PERIODS OF SHOWERS AND THUNDERSTORMS WILL PERSIST UNTIL LATE THURSDAY NIGHT OR EARLY FRIDAY MORNING WHEN A COLD FRONT MOVES THROUGH THE AREA. LIGHT TO MODERATE OFFSHORE WINDS BEHIND THE FRONT WILL PERSIST THROUGH EARLY SATURDAY. LIGHT ONSHORE WINDS THAT RETURN TO THE AREA SATURDAY NIGHT AND STRENGTHEN ON SUNDAY AND MONDAY ARE EXPECTED TO PERSIST THROUGH ALL OF NEXT WEEK. 42 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 79 67 77 57 79 / 60 30 50 30 10 HOUSTON (IAH) 79 67 80 64 81 / 60 40 70 40 10 GALVESTON (GLS) 75 70 76 69 76 / 60 40 50 30 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH THROUGH THIS EVENING FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS... COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS... LIBERTY...MONTGOMERY...POLK...SAN JACINTO...WALKER... WALLER...WASHINGTON...WHARTON. GM...NONE. && $$ DISCUSSION...46 AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
359 PM EDT WED APR 20 2016 .SYNOPSIS... HIGH PRESSURE OVER THE REGION, WILL MOVE OFF THE COAST ON THURSDAY. LOW PRESSURE OVER THE CENTRAL PORTION OF THE NATION WILL MOVE NORTHEASTWARD INTO EASTERN CANADA BY FRIDAY, AND ITS ASSOCIATED COLD FRONT WILL MOVE THROUGH OUR REGION FRIDAY NIGHT. HIGH PRESSURE WILL MOVE BACK INTO THE AREA FOR THE WEEKEND, WITH LOW PRESSURE IMPACTING THE AREA AROUND TUESDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... REST OF THIS AFTERNOON: MAX TEMPS NEARING 70. ITS BEEN A BEAUTIFUL DAY. A WIND SHIFT TO SOUTHEAST WILL BE NEARING THE I95 CORRIDOR BY 6 OR 7 PM WITH DEWPOINTS RISING. HRRR SEEMS TO HAVE A GOOD HANDLE. TONIGHT...ISSUED A FROST ADVISORY IN THE MOST FAVORED AREAS FROM THE FORECAST WHERE MINS OF LESS THAN OR EQUAL TO 35 ARE ANTICIPATED. ITS POSSIBLE THAT THERE MAY NEED TO BE A SMALL AREAL EXPANSION FOR THIS SHORT DURATION FROST POTENTIAL, ESPECIALLY SOMERSET COUNTY, THIS MORNINGS MINS WERE 28F IN WALPACK OF NW NJ AND MANY 30-36F LOWS FROM NORTHERN CAPE MAY COUNTY NORTH THROUGH THE PINEBARRENS REGION ON UP INTO NW NJ. NEARLY CALM WIND WITH MOSTLY CLEAR SKY (A BIT OF CIRRUS TOWARD DAWN). THIS PART OF THE FORECAST IS A 50 50 BLEND OF THE 12Z/20 GFS/NAM GUIDANCE THEN COOLED 2-4F IN THE COUNTRYSIDE THROUGH 11Z THURSDAY PER EXPECTED NEARLY IDEAL RADIATIONAL COOLING CONDITIONS BUT ALSO REFLECTS THE VERY DRY AIR BOUNDARY LAYER, DESPITE ANY SHALLOW SFC DEWPOINT RISE ASSOCIATED WITH THE SE SEA BREEZE REACHING THE POCONOS AROUND 11 PM. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... THURSDAY...A MOSTLY SUNNY RAPIDLY WARMING START WITH GUSTY SW WINDS 15-20 MPH DEVELOPING LATE MORNING. INCREASING MID AND LATE AFTERNOON CLOUD COVER AHEAD OF A WEAK INSTABILITY BURST THAT COULD SPREAD SPRINKLES INTO NE PA BY 6PM. FIRE WEATHER IS THE MAIN CONCERN THURSDAY AND WITH SOME UNCERTAINTY AS DISCUSSED IN THE FIRE WEATHER SECTION. WIND GUSTS MAY APPROACH 25 MPH DURING THE AFTERNOON, ESPECIALLY NORTH OF PHILADELPHIA. THIS PART OF THE FCST WAS MOSTLY THE 12Z/20 GFS WARMER TEMP GUIDANCE, THE DRIER NAM GUIDANCE AND A BLEND OF THE NAM/GFS WINDS AND SKYCOVER. CONFIDENCE ON TEMPS REACHING OR EXCEEDING THESE VALUES IS HIGH. I COULD SEE TEMPS 2-3F WARMER THAN CURRENTLY FCST. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... THE PERSISTENT AREA OF HIGH PRES WILL BE OFF THE COAST AND MOVG AWAY FROM THE AREA AT THE START OF THE PD. LOW PRES NR THE GRTLKS WILL MOVE NEWD INTO ERN CANADA ON FRI. ITS ATTENDANT CDFNT WILL MOVE THRU THE REGION FRI NIGHT. PRECIP CHCS WILL INCREASE DURG THE DAY ON FRI WITH THE HIGHEST CHCS FRI ERLY FRI NIGHT WITH THE CFP. THE MDL GUID DIFFERS SLIGHTLY, WITH THE GFS FASTER THAN THE ECMWF. THE NAM/WRF SUPPORTS THE SLOWER TIMING. WPC GUID BACKS THE FASTER GFS. IF THE FASTER TIMING IS CORRECT, THE PRECIP WOULD END LATE FRI NIGHT. IF THE SLOWER TIMING IS CORRECT, THE PRECIP WILL END DURG SAT MRNG. THE ECMWF IS OFTEN SLOWER WITH CFP, BUT SINCE IT HAS SUPPORT FROM OTHER MDLS, HAVE LEFT SOME LOW POPS IN FOR SAT MRNG. HIGH PRES BUILDS BACK IN FOR SAT INTO SUN, SO ANOTHER NICE WEEKEND IS IN STORE. THEN, A STRONG AREA OF LOW PRES WILL MOVE ACRS THE NCNTL PLAINS. ITS WMFNT WILL EXTEND EWD ACRS THE GRTLKS INTO NEW ENG OR NRN MID ATLC. THE ECMWF IS A BIT FURTHER S THAN THE GFS WITH THIS FRONT. IF THE EC IS CORRECT, IT WOULD POTENTIALLY SUPPORT DOME LIGHT QPF OVER NRN AREAS LATE SUN NIGHT OR MON MRNG, BUT THE EC IS CLEARLY THE OUTLIER HERE. ALL THE OTHER MDLS HAVE A MUCH MORE NLY POSN OF THIS BNDRY. THE LOW MOVES FURTHER E MONDAY NIGHT TO A POSN SOMEWHERE OVER PA/NY AND PRECIP CHCS WILL INCREASE, BEFORE THE LOW MOVES AWAY ON TUE, THE CDFNT CROSSES THE REGION AND POPS DECLINE ONCE AGAIN. TEMPS ARE EXPECTED TO BE AOA NRML THRU THE PD. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REST OF TODAY...VFR CLEAR. LIGHT VARIABLE WIND TRENDING SOUTHEAST TO SOUTH LATE IN THE DAY. THE COASTAL SEABREEZE WILL BE MOVING WESTWARD- INLAND THIS AFTERNOON WITH THOSE SEA BREEZES HAVING A FEW GUSTS TO 18-21 KT. THIS WIND SHIFT COULD REACH PHL LATE AFTERNOON OR EARLY EVENING AND ATTEMPTED TIMING IS IN THE TAFS. TONIGHT...VFR CLEAR THEN PATCHY AC/CIRRUS TOWARD 10Z/21. WIND BECOMING NEARLY CALM LATER THIS EVENING THEN LIGHT SOUTHERLY TOWARD MORNING. THURSDAY...VFR SCT-BKN CLOUDS AOA 12000 FT DURING THE MORNING WITH MULTI LAYERS DEVELOPING BY 21Z AOA 5000 FT. S-SW WIND THURSDAY WITH MIDDAY-AFTERNOON GUSTS AROUND 20 KT. ABOVE AVERAGE CONFIDENCE. OUTLOOK... THU NIGHT. VFR WITH SOME MVFR/IFR PSBL IN SHRA MAINLY N AND W. LOW TO MDT CONFIDENCE. FRI...MVFR/IFR PSBL IN SHRA AND TSRA AHEAD OF CFP. STILL SOME DIFFS WITH TIMING OF CDFNT. MDT CONFIDENCE. FRI NIGHT...CFP AND WSHFT. MVFR/IFR PSBL ERLY...THEN IMPROVING TO VFR LATE. HIGH CONFIDENCE. SAT THRU SUN...VFR. HIGH PRES. HIGH CONFIDENCE. MON...VFR ERLY...LOWERING CONDS LATE AS NEXT SYS APPROACHES. MDT CONFIDENCE. && .MARINE... NO MARINE HEADLINES ANTICIPATED THROUGH MOST OF THURSDAY. STILL A DOMINANT EASTERLY SWELL OF 2-3 FT AND 8-10 SECONDS ON THE ATLANTIC WATERS...A RESIDUAL FROM LAST WEEKEND. A FEW ONSHORE GUSTS NEAR OR JUST ABOVE 20 KT ARE LIKELY INTO THIS EVENING, ESPECIALLY DELAWARE BAY WHERE ISOLATED GUSTS TO 24 KT ARE POSSIBLE. WIND TURNS LIGHT SOUTH LATER TONIGHT THEN GUSTY S-SW 20 KT THURSDAY AFTERNOON. OUTLOOK... THU NIGHT THRU FRI...SLY WILL BE PRESENT AND WE WILL PROB BE LOOKING AT MARGINAL SCA CONDS BY FRI. WE MAY BE JUST UNDER SCA CONDS THU NIGHT. FRI NIGHT...WIND SHIFTS TO W THEN NW BEHIND CFP AND DECREASE. SEAS DECREASE AS WELL. NO MARINE HEADLINES EXPECTED. SAT THRU SUN...NO MARINE HEADLINES ANTICIPATED. MON...SLY FLOW INCREASES IN ADVANCE OF THE NEXT LOW PRES SYS AND SEAS RESPOND IN KIND. SCA FLAGS MAY BE NEEDED BY THE END OF THE PD. && .FIRE WEATHER... FIRE WEATHER WATCH IN EFFECT: IF CONDITIONS ARE FORECAST THE SAME OR WORSE AT 330 AM THURSDAY, OUR PARTNERS HAVE GIVEN THE GO AHEAD TO CONVERT TO A WARNING. THERE IS STILL AN ELEMENT OF DOUBT REGARDING THE WIND ELEMENT AND THE SOUTHWESTERN EXTENT OF THE RH BELOW 30 PERCENT. WE THINK MODEL GUIDANCE IS TOO MOIST TOO SOON. WE WONT KNOW FOR SURE UNTIL 15Z THURSDAY BUT THE VERY LOW DEWPOINTS IN THE WESTERN PART OF VIRGINIA ARE A SIGN OF THE DRY ALOFT THAT STILL CAN MIX DOWN TOMORROW ON THE GUSTY SW FLOW. && .EQUIPMENT... BUOY 44009 (DE BAY BUOY LOCATED 26 NM SOUTHEAST OF CAPE MAY NJ) IS SLATED FOR RESTORATION OF WIND INFORMATION AROUND JULY 5, 2016. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY AFTERNOON FOR PAZ054-055-060>062-071-103>106. NJ...FROST ADVISORY FROM 3 AM TO 8 AM EDT THURSDAY FOR NJZ001- 007>009-020-022-027. FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY AFTERNOON FOR NJZ001-007>010-012-013-015-017>020-027. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...NIERENBERG NEAR TERM...DRAG 4P SHORT TERM...DRAG 4P LONG TERM...NIERENBERG AVIATION...DRAG/NIERENBERG 4P MARINE...DRAG/NIERENBERG 4P FIRE WEATHER...4P EQUIPMENT...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
335 PM EDT WED APR 20 2016 .SYNOPSIS... HIGH PRESSURE OVER THE REGION, WILL MOVE OFF THE COAST ON THURSDAY. LOW PRESSURE OVER THE CENTRAL PORTION OF THE NATION WILL MOVE NORTHEASTWARD INTO EASTERN CANADA BY FRIDAY, AND ITS ASSOCIATED COLD FRONT WILL MOVE THROUGH OUR REGION FRIDAY NIGHT. HIGH PRESSURE WILL MOVE BACK INTO THE AREA FOR THE WEEKEND, WITH LOW PRESSURE IMPACTING THE AREA AROUND TUESDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... 2PM UPDATE: TEMPS MAY MAX AT 69F AROUND 430PM. BRILLIANT SUNSHINE. WINDS HAVE DIMINISHED PER HRRR EXCEPT AS PER HRRR JUST BEHIND THE SEABREEZE. RH THIS AFTN DOWN TO 15 PCT. TONIGHT...AM A LITTLE CONCERNED ABOUT FROST POTENTIAL AND MAY ISSUE A FROST ADVY FOR PORTION OF NJ IN THE 330 PM FCST. THIS MORNINGS MINS WERE 28F IN WALPACK OF NW NJ AND MANY 30-36F LOWS FROM NORTHERN CAPE MAY COUNTY NORTH THROUGH THE PINEBARRENS REGION ON UP INTO NW NJ. NEARLY CALM WIND WITH MOSTLY CLEAR SKY (A BIT OF CIRRUS TOWARD DAWN). PROPOSED FROST ADVY WOULD BE INTERIOR OCEAN SE BURLINGTON, INTERIOR ATLC AS WELL AS SUSSEX, WARREN, MORRIS AND NORTHAMPTON COUNTIES. THIS PART OF THE FORECAST IS A 50 50 BLEND OF THE 12Z/20 GFS/NAM GUIDANCE THEN COOLED 2-4F IN THE COUNTRYSIDE THROUGH 11Z THURSDAY PER EXPECTED NEARLY IDEAL RADIATIONAL COOLING CONDITIONS BUT ALSO REFLECTS THE MUCH LOWER THAN FCST DEWPOINTS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... THURSDAY...A SUNNY RAPIDLY WARMING START WITH GUSTY SW WINDS 15-20 MPH DEVELOPING LATE MORNING. INCREASING MID AND LATE AFTERNOON CLOUD COVER AHEAD OF A WEAK INSTABILITY BURST THAT COULD SPREAD SPRINKLES INTO NE PA BY 6PM. FIRE WEATHER IS THE MAIN CONCERN THURSDAY AND WITH SOME UNCERTAINTY AS DISCUSSED IN THE FIRE WEATHER SECTION. WIND GUSTS MAY APPROACH 25 MPH DURING THE AFTERNOON, ESPECIALLY NORTH OF PHILADELPHIA. THIS PART OF THE FCST WAS MOSTLY THE 12Z/20 GFS WARMER TEMP GUIDANCE, THE DRIER NAM GUIDANCE AND A BLEND OF THE NAM/GFS WINDS AND SKYCOVER. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... THE PERSISTENT AREA OF HIGH PRES WILL BE OFF THE COAST AND MOVG AWAY FROM THE AREA AT THE START OF THE PD. LOW PRES NR THE GRTLKS WILL MOVE NEWD INTO ERN CANADA ON FRI. ITS ATTENDANT CDFNT WILL MOVE THRU THE REGION FRI NIGHT. PRECIP CHCS WILL INCREASE DURG THE DAY ON FRI WITH THE HIGHEST CHCS FRI ERLY FRI NIGHT WITH THE CFP. THE MDL GUID DIFFERS SLIGHTLY, WITH THE GFS FASTER THAN THE ECMWF. THE NAM/WRF SUPPORTS THE SLOWER TIMING. WPC GUID BACKS THE FASTER GFS. IF THE FASTER TIMING IS CORRECT, THE PRECIP WOULD END LATE FRI NIGHT. IF THE SLOWER TIMING IS CORRECT, THE PRECIP WILL END DURG SAT MRNG. THE ECMWF IS OFTEN SLOWER WITH CFP, BUT SINCE IT HAS SUPPORT FROM OTHER MDLS, HAVE LEFT SOME LOW POPS IN FOR SAT MRNG. HIGH PRES BUILDS BACK IN FOR SAT INTO SUN, SO ANOTHER NICE WEEKEND IS IN STORE. THEN, A STRONG AREA OF LOW PRES WILL MOVE ACRS THE NCNTL PLAINS. ITS WMFNT WILL EXTEND EWD ACRS THE GRTLKS INTO NEW ENG OR NRN MID ATLC. THE ECMWF IS A BIT FURTHER S THAN THE GFS WITH THIS FRONT. IF THE EC IS CORRECT, IT WOULD POTENTIALLY SUPPORT DOME LIGHT QPF OVER NRN AREAS LATE SUN NIGHT OR MON MRNG, BUT THE EC IS CLEARLY THE OUTLIER HERE. ALL THE OTHER MDLS HAVE A MUCH MORE NLY POSN OF THIS BNDRY. THE LOW MOVES FURTHER E MONDAY NIGHT TO A POSN SOMEWHERE OVER PA/NY AND PRECIP CHCS WILL INCREASE, BEFORE THE LOW MOVES AWAY ON TUE, THE CDFNT CROSSES THE REGION AND POPS DECLINE ONCE AGAIN. TEMPS ARE EXPECTED TO BE AOA NRML THRU THE PD. && .AVIATION /19Z WEDNESDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REST OF TODAY...VFR CLEAR. LIGHT VARIABLE WIND TRENDING SOUTHEAST TO SOUTH LATE IN THE DAY. THE COASTAL SEABREEZE WILL BE MOVING WESTWARD- INLAND THIS AFTERNOON WITH THOSE SEA BREEZES HAVING A FEW GUSTS TO 18-21 KT. THIS WIND SHIFT COULD REACH PHL LATE AFTERNOON OR EARLY EVENING AND ATTEMPTED TIMING IS IN THE 18Z TAFS. TONIGHT...VFR CLEAR THEN PATCHY AC/CIRRUS TOWARD 10Z/21. WIND BECOMING NEARLY CALM LATER THIS EVENING THEN LIGHT SOUTHERLY TOWARD MORNING. THURSDAY...VFR SCT-BKN CLOUDS AOA 12000 FT DURING THE MORNING WITH MULTI LAYERS DEVELOPING BY 21Z AOA 5000 FT. S-SW WIND THURSDAY WITH MIDDAY-AFTERNOON GUSTS AROUND 20 KT. OUTLOOK... THU NIGHT. VFR WITH SOME MVFR/IFR PSBL IN SHRA MAINLY N AND W. LOW TO MDT CONFIDENCE. FRI...MVFR/IFR PSBL IN SHRA AND TSRA AHEAD OF CFP. STILL SOME DIFFS WITH TIMING OF CDFNT. MDT CONFIDENCE. FRI NIGHT...CFP AND WSHFT. MVFR/IFR PSBL ERLY...THEN IMPROVING TO VFR LATE. HIGH CONFIDENCE. SAT THRU SUN...VFR. HIGH PRES. HIGH CONFIDENCE. MON...VFR ERLY...LOWERING CONDS LATE AS NEXT SYS APPROACHES. MDT CONFIDENCE. && .MARINE... NO MARINE HEADLINES ANTICIPATED THROUGH MOST OF THURSDAY. STILL A DOMINANT EASTERLY SWELL OF 3 FT AND 10 SECONDS ON THE ATLANTIC WATERS...A RESIDUAL FROM LAST WEEKEND. A FEW ONSHORE GUSTS NEAR OR JUST ABOVE 20 KT ARE POSSIBLE THIS AFTERNOON. WIND TURNS LIGHT SOUTH TONIGHT THEN GUSTY S-SW 20 KT THURSDAY AFTERNOON. OUTLOOK... THU NIGHT THRU FRI...SLY WILL BE PRESENT AND WE WILL PROB BE LOOKING AT MARGINAL SCA CONDS BY FRI. WE MAY BE JUST UNDER SCA CONDS THU NIGHT. FRI NIGHT...WIND SHIFTS TO W THEN NW BEHIND CFP AND DECREASE. SEAS DECREASE AS WELL. NO MARINE HEADLINES EXPECTED. SAT THRU SUN...NO MARINE HEADLINES ANTICIPATED. MON...SLY FLOW INCREASES IN ADVANCE OF THE NEXT LOW PRES SYS AND SEAS RESPOND IN KIND. SCA FLAGS MAY BE NEEDED BY THE END OF THE PD. && .FIRE WEATHER... SPS ISSUED FOR NJ AND PA WILL EXPIRE AT 19Z. RH NOW DOWN BELOW 25 PCT EXCEPT COOLER SEABREEZED COASTAL REAL ESTATE. LOOKING AHEAD TO THURSDAY...SOUTHWEST WINDS BECOME INCREASINGLY GUSTY IN THE AFTERNOON...UP TO AT LEAST 20 MPH AT TIMES. RH VALUES ALSO DECREASE IN THE AFTERNOON...BELOW 30 PERCENT OVER PORTIONS OF THE AREA, MAINLY PHL NORTHWARD.THE MAIN UNCERTAINTY WILL BE THE MAGNITUDE OF THE WIND GUSTS...WITH RED FLAG CONDITIONS REMAINING A POSSIBILITY. COLLABORATING A POSSIBLE FIRE WEATHER WATCH ISSUANCE AROUND 230 PM. && .EQUIPMENT... BUOY 44009 (DE BAY BUOY LOCATED 26 NM SOUTHEAST OF CAPE MAY NJ) IS SLATED FOR RESTORATION OF WIND INFORMATION AROUND JULY 5, 2016. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...NIERENBERG NEAR TERM...DRAG SHORT TERM...DRAG LONG TERM...NIERENBERG AVIATION...DRAG/NIERENBERG MARINE...DRAG/NIERENBERG FIRE WEATHER... EQUIPMENT...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
210 PM EDT WED APR 20 2016 .SYNOPSIS... HIGH PRESSURE IS BUILDING SOUTHEAST OVER THE MID ATLANTIC STATES THIS AFTERNOON. LOW PRESSURE IN THE UPPER MISSISSIPPI VALLEY ON THURSDAY WILL MOVE INTO THE SAINT LAWRENCE VALLEY AND LEAD TO A COLD FRONTAL PASSAGE ACROSS OUR AREA FRIDAY NIGHT. CANADIAN HIGH PRESSURE WILL SLOWLY MOVE OVER OUR REGION THIS WEEKEND. A COMPLEX FRONTAL BOUNDARY WILL SETUP OVER OUR AREA BY EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... 2PM UPDATE: TEMPS MAY MAX AT 69F AROUND 430PM. BRILLIANT SUNSHINE. WINDS HAVE DIMINISHED PER HRRR EXCEPT AS PER HRRR JUST BEHIND THE SEABREEZE. RH THIS AFTN DOWN TO 15 PCT. TONIGHT...AM A LITTLE CONCERNED ABOUT FROST POTENTIAL AND MAY ISSUE A FROST ADVY FOR PORTION OF NJ IN THE 330 PM FCST. THIS MORNINGS MINS WERE 28F IN WALPACK OF NW NJ AND MANY 30-36F LOWS FROM NORTHERN CAPE MAY COUNTY NORTH THROUGH THE PINEBARRENS REGION ON UP INTO NW NJ. NEARLY CALM WIND WITH MOSTLY CLEAR SKY (A BIT OF CIRRUS TOWARD DAWN). PROPOSED FROST ADVY WOULD BE INTERIOR OCEAN SE BURLINGTON, INTERIOR ATLC AS WELL AS SUSSEX, WARREN, MORRIS AND NORTHAMPTON COUNTIES. THIS PART OF THE FORECAST IS A 50 50 BLEND OF THE 12Z/20 GFS/NAM GUIDANCE THEN COOLED 2-4F IN THE COUNTRYSIDE THROUGH 11Z THURSDAY PER EXPECTED NEARLY IDEAL RADIATIONAL COOLING CONDITIONS BUT ALSO REFLECTS THE MUCH LOWER THAN FCST DEWPOINTS. && .SHORT TERM /THURSDAY/... THURSDAY...A SUNNY RAPIDLY WARMING START WITH GUSTY SW WINDS 15-20 MPH DEVELOPING LATE MORNING. INCREASING MID AND LATE AFTERNOON CLOUD COVER AHEAD OF A WEAK INSTABILITY BURST THAT COULD SPREAD SPRINKLES INTO NE PA BY 6PM. FIRE WEATHER IS THE MAIN CONCERN THURSDAY AND WITH SOME UNCERTAINTY AS DISCUSSED IN THE FIRE WEATHER SECTION. WIND GUSTS MAY APPROACH 25 MPH DURING THE AFTERNOON, ESPECIALLY NORTH OF PHILADELPHIA. THIS PART OF THE FCST WAS MOSTLY THE 12Z/20 GFS WARMER TEMP GUIDANCE, THE DRIER NAM GUIDANCE AND A BLEND OF THE NAM/GFS WINDS AND SKYCOVER. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... MID LEVEL LOW AT THE CENTER OF THE RECENT BLOCKING PATTERN WILL GRADUALLY MOVE EASTWARD, BECOMING AN OPEN WAVE AS IT REACHES THE MIDDLE ATLANTIC COAST, ACCOMPANIED BY A SLOW MOVING COLD FRONTAL PASSAGE FRIDAY NIGHT. MEANWHILE, CLOSED MID-LEVEL VORTEX OVER THE CLIMATOLOGICALLY FAVORED BAFFIN ISLAND SLOWLY MOVES SOUTHEASTWARD, RE-ESTABLISHING ITSELF JUST NORTHEAST OF JAMES BAY BY EARLY NEXT WEEK. THIS WILL ESTABLISH A FAST, WESTERLY FLOW ACROSS THE REGION LATE THIS WEEKEND INTO EARLY NEXT WEEK, WHICH SEVERAL SHORTWAVE DISTURBANCES WILL TRAVERSE, AS THEY EXIT A MEAN TROUGH SETTING UP OVER THE WESTERN CONUS DURING THIS TIME FRAME. THE MOST UNCERTAINTY IS WITH REGARD TO THE EVOLUTION OF A FRONTAL BOUNDARY EARLY NEXT WEEK, AS TO WHERE IT SETS UP WITH RESPECT TO OUR REGION, AND THE RESULTANT SENSIBLE WEATHER IMPACTS. FRIDAY...THERE IS SOME CONVECTIVE POTENTIAL, AS A COLD FRONT IS POISED TO MOVE THROUGH OUR REGION BY FRI NIGHT. INSTABILITY WILL BE LIMITED GIVEN CONSIDERABLE CLOUD COVER, WITH BEST CHANCE FOR THUNDER TO OUR SOUTHWEST. THEREFORE, HAVE NOT ADDED THUNDER TO THE FORECAST ATTM. SATURDAY AND SUNDAY...BENIGN PERIOD OF WEATHER WITH HIGH PRESSURE IN CONTROL. THE MAIN CONCERN WILL BE THE POTENTIAL FOR A FROST/FREEZE SUNDAY MORNING, PARTICULARLY NORTH OF THE I-78 CORRIDOR. ALTHOUGH THE BOUNDARY LAYER IS EXPECTED TO DECOUPLE, MID AND HIGH LEVEL MOISTURE MAY PREVENT IDEAL RADIATIONAL COOLING, SO THERE IS CONSIDERABLE UNCERTAINTY AT THIS TIME. SUNDAY NIGHT THRU TUESDAY...AS MENTIONED, THERE IS CONSIDERABLE UNCERTAINTY DURING THIS TIME FRAME, WHICH GENERALLY LEADS TO BELOW AVERAGE CONFIDENCE IN OUTCOMES. A SLOW MOVING FRONTAL BOUNDARY WILL CROSS THE REGION, WITH POSSIBLY A FEW WAVES OF LOW PRESSURE TRAVERSING IT. GENERALLY UNSETTLED WEATHER IS ANTICIPATED, WITH SOME BENEFICIAL RAINFALL POSSIBLE. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REST OF TODAY...VFR CLEAR. LIGHT VARIABLE WIND TRENDING SOUTHEAST TO SOUTH LATE IN THE DAY. THE COASTAL SEABREEZE WILL BE MOVING WESTWARD- INLAND THIS AFTERNOON WITH THOSE SEA BREEZES HAVING A FEW GUSTS TO 18-21 KT. THIS WIND SHIFT COULD REACH PHL LATE AFTERNOON OR EARLY EVENING AND ATTEMPTED TIMING IS IN THE 18Z TAFS. TONIGHT...VFR CLEAR THEN PATCHY AC/CIRRUS TOWARD 10Z/21. WIND BECOMING NEARLY CALM LATER THIS EVENING THEN LIGHT SOUTHERLY TOWARD MORNING. THURSDAY...VFR SCT-BKN CLOUDS AOA 12000 FT DURING THE MORNING WITH MULTI LAYERS DEVELOPING BY 21Z AOA 5000 FT. S-SW WIND THURSDAY WITH MIDDAY-AFTERNOON GUSTS AROUND 20 KT. OUTLOOK... VFR CONDITIONS THU NIGHT. MVFR POSSIBLE IN SHRA AND TSRA FRI AND FRI NIGHT WITH THE PASSAGE OF A COLD FRONT, AS WELL AS A LOW PROBABILITY OF WEST-SOUTHWEST WIND GUSTS TO 25 KNOTS. VFR IS ANTICIPATED BOTH SAT AND SUN AS HIGH PRESSURE SETTLES OVER THE TERMINALS. && .MARINE... NO MARINE HEADLINES ANTICIPATED THROUGH MOST OF THURSDAY. STILL A DOMINANT EASTERLY SWELL OF 3 FT AND 10 SECONDS ON THE ATLANTIC WATERS...A RESIDUAL FROM LAST WEEKEND. A FEW ONSHORE GUSTS NEAR OR JUST ABOVE 20 KT ARE POSSIBLE THIS AFTERNOON. WIND TURNS LIGHT SOUTH TONIGHT THEN GUSTY S-SW 20 KT THURSDAY AFTERNOON. OUTLOOK... A COLD FRONT WILL TRAVERSE THE COASTAL WATERS FRIDAY NIGHT. SOUTHWEST WINDS IN ADVANCE OF THIS FRONT ARE EXPECTED TO FALL JUST SHORT OF SCA THRESHOLD THURSDAY AFTERNOON INTO FRIDAY NIGHT, BUT IT/S A CLOSE CALL, AS WAVE HEIGHTS HAVE A BETTER CHANCE OF MEETING THE 5FT CRITERIA FOR SCA FOR HAZARDOUS SEAS. THERE IS GREATER UNCERTAINTY WITH REGARD TO WHETHER NORTH-NORTHWEST WINDS REACH SCA LEVELS BEHIND THIS FRONT FOR A BRIEF PERIOD OF TIME BOTH SATURDAY MORNING AND AGAIN SATURDAY NIGHT. HIGH PRESSURE WILL MOVE OVER THE COASTAL WATERS SUNDAY, WITH TRANQUIL, SUB-SCA CONDITIONS EXPECTED. && .FIRE WEATHER... SPS ISSUED FOR NJ AND PA WILL EXPIRE AT 19Z. RH NOW DOWN BELOW 25 PCT EXCEPT COOLER SEABREEZED COASTAL REAL ESTATE. LOOKING AHEAD TO THURSDAY...SOUTHWEST WINDS BECOME INCREASINGLY GUSTY IN THE AFTERNOON...UP TO AT LEAST 20 MPH AT TIMES. RH VALUES ALSO DECREASE IN THE AFTERNOON...BELOW 30 PERCENT OVER PORTIONS OF THE AREA, MAINLY PHL NORTHWARD.THE MAIN UNCERTAINTY WILL BE THE MAGNITUDE OF THE WIND GUSTS...WITH RED FLAG CONDITIONS REMAINING A POSSIBILITY. COLLABORATING A POSSIBLE FIRE WEATHER WATCH ISSUANCE AROUND 230 PM. && .EQUIPMENT... BUOY 44009 (DE BAY BUOY LOCATED 26 NM SOUTHEAST OF CAPE MAY NJ) IS SLATED FOR RESTORATION OF WIND INFORMATION AROUND JULY 5, 2016. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...DRAG/FRANCK 208 NEAR TERM...DRAG 208 SHORT TERM...DRAG 208 LONG TERM...FRANCK AVIATION...DRAG/FRANCK 208 MARINE...DRAG/FRANCK 208 FIRE WEATHER...208 EQUIPMENT...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
327 PM EDT WED APR 20 2016 .SYNOPSIS... A WEAK COLD FRONT WILL DISSIPATE NEAR THE CHARLESTON AREA TONIGHT. ATLANTIC HIGH PRESSURE WILL PREVAIL THURSDAY INTO FRIDAY. A COLD FRONT WILL MOVE THROUGH FRIDAY NIGHT INTO SATURDAY...FOLLOWED BY HIGH PRESSURE INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... THE WEAK BACKDOOR COLD FRONT WILL SETTLE IN ACROSS THE CHARLESTON TRI-COUNTY AREA THIS EVENING AND DISSIPATE. THE REMNANTS OF THE FRONT WILL LINGER WILL THROUGH SUNRISE WITH MODELS SHOWING LOW- LEVEL POOLING IN ITS VICINITY. THIS COULD PROMOTE SOME STRATUS BUILD DOWN AND POSSIBLY FOG AFTER MIDNIGHT...BUT RAP POINT SOUNDINGS AT KCHS..KDYB AND KMKS ARE NOT OVERLY IMPRESSIVE FOR SIGNIFICANT FOG FORMATION. THIS IS CERTAINLY SOMETHING THAT WILL NEED TO BE MONITORED THROUGH THE NIGHT. WILL CARRY PATCHY FOG FOR THE CHARLESTON TRI-COUNTY AREA FOR NOW AND SHOW SKIES BECOMING MOSTLY CLOUDY FOR AREAS ALONG/NORTH OF I-26. ELSEWHERE... CONDITIONS WILL FAVOR JUST SHALLOW GROUND FOG A FEW HOURS PRIOR TO SUNRISE. ANOTHER A-TYPICAL TEMPERATURE DISTRIBUTION IS ON TAP TONIGHT WITH THE COOLEST CONDITIONS ONCE AGAIN OCCURRING ACROSS INTERIOR SOUTHEAST GEORGIA...MORE SPECIFICALLY IN THE FORT STEWART- LUDOWICI-DARIEN CORRIDOR. HIGH CLOUDS ARE FORECAST TO THIN ENOUGH TO SUPPORT MODEST RADIATIONAL COOLING WITH TEMPERATURE LIKELY CRATERING JUST BEFORE DAYBREAK. STRATUS SHOULD KEEP TEMPERATURES A BIT MORE ELEVATED ACROSS THE NORTHERN ZONES. LOWS WILL RANGE FROM THE UPPER 50S/NEAR 60 ACROSS THE CHARLESTON TRI-COUNTY AREA TO THE MID 50S ACROSS THE DARIEN-FORT STEWART-LUDOWICI CORRIDOR. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... THURSDAY...SURFACE HIGH PRESSURE IN THE ATLANTIC WILL BE SHIFTING EASTWARD WHILE A RIDGE AXIS IS POSITIONED OVER THE EAST COAST. MOISTURE GRADUALLY INCREASES AS WEAK CONVERGENCE SETS UP JUST OFFSHORE. THIS MAY LEAD TO A FEW LIGHT SHOWERS OFFSHORE. IT IS NOT OUT OF THE QUESTION THAT A STRAY LIGHT SHOWER COULD REACH NORTHERN CHARLESTON COUNTY IN THE AFTERNOON...BUT THE PROBABILITIES IN THIS OCCURRING ARE LOW. REGARDLESS...WE HAVE MAINTAINED A BRIEF PERIOD OF SLIGHT CHANCE POPS IN THE FORECAST TO ACCOUNT FOR THIS. TEMPERATURES WILL BE IN THE LOWER 80S AWAY FROM THE LOCALLY COOLER COAST. INCREASING CLOUDS LATE IN THE DAY AND ESPECIALLY AT NIGHT SHOULD KEEP LOWS MILD...IN THE LOW 60S. FRIDAY...THE ATLANTIC SURFACE HIGH WILL BE JUST FAR ENOUGH SHORE TO LOSE INFLUENCE OVER OUR AREA. INSTEAD THE DOMINANT FEATURE WILL BECOME A TROUGH MOVING FROM THE GREAT LAKES REGION INTO THE NORTHEAST. THIS FEATURE WILL PUSH A COLD FRONT TOWARDS OUR AREA. S/SW WINDS AT THE SURFACE AND AROUND 25 KT OF SW FLOW AT 850 MB WILL PUSH PWATS TO NEAR 1.50 INCHES. THIS COMBINED WITH SOME INSTABILITY AND ENERGY FROM A PASSING SHORTWAVE WILL GENERATE SHOWERS AND THUNDERSTORMS. THE SEVERE THREAT IS LOW BECAUSE INSTABILITY IS UNIMPRESSIVE AND SHEAR IS WEAK. DESPITE CLOUDY SKIES...COMPRESSIONAL HEATING AHEAD OF THE FRONT SHOULD ALLOW HIGHS TO REACH AROUND 80 DEGREES. MODELS HAVE COME INTO BETTER AGREEMENT WITH TIMING OF FRONTAL PASSAGE...SHOWING THE FRONT CROSSING THE LOCAL AREA LATE FRIDAY NIGHT INTO EARLY SATURDAY. ADJUSTED THE POPS AND WEATHER GRIDS TO BETTER REFLECT THIS TIMING. PRECIPITATION WILL QUICKLY DECREASE AS THE FRONT MOVES OFFSHORE EARLY SATURDAY MORNING. QPF SHOULD GENERALLY BE AROUND 0.25 INCHES. FRIDAY NIGHT LOWS WILL BE MILD AGAIN...IN THE LOWER 60S. SATURDAY...SHORTWAVE ENERGY LAGGING BEHIND THE FRONT IN COMBINATION WITH WEAK INSTABILITY MAY BE ENOUGH TO ALLOW A FEW SHOWERS/ISOLATED THUNDERSTORMS TO DEVELOP IN THE AFTERNOON. SLIGHT CHANCE POPS REMAIN IN THE FORECAST. HIGHS WILL RANGE FROM THE UPPER 70S IN THE NORTH...TO THE LOWER 80S IN THE SOUTH. && .LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/... HIGH PRESSURE WILL BUILD IN FROM THE NORTH ON SUNDAY BEFORE SHIFTING INTO THE ATLANTIC BY MONDAY. THE FORECAST AREA WILL LARGELY REMAIN UNDER THE INFLUENCE OF THE SURFACE HIGH THROUGH MIDDLE OF NEXT WEEK. MODELS DO HINT THAT A BACKDOOR COLD FRONT MAY TRY TO DESCEND INTO THE AREA LATE TUESDAY OR WEDNESDAY HOWEVER THERE ARE STILL LARGE DISCREPANCIES BETWEEN MODELS ON TIMING AND EVOLUTION OF THIS FEATURE. TEMPERATURES WILL BE ON A WARMING TREND THROUGH THE PERIOD WITH HIGHS SOLIDLY IN THE 80S EACH AFTERNOON. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... VFR. SHALLOW GROUND FOG IS POSSIBLE AT BOTH TERMINALS TONIGHT AS DEWPOINTS RISE AND WINDS GO CALM/VARIABLE...BUT BETTER CHANCES FOR IMPACTS WILL BE AT KCHS. LOW STRATUS IS A POSSIBILITY CLOSER TO THE BACKDOOR FRONT...BUT THINK THE HIGHEST CHANCES WILL REMAIN NORTH OF KCHS. EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE POSSIBLE FRIDAY INTO EARLY SATURDAY AS A COLD FRONT MOVES THROUGH THE AREA WITH SHOWERS AND THUNDERSTORMS. && .MARINE... TONIGHT...WINDS WILL GRADUALLY TURN ONSHORE ACROSS THE ENTIRE MARINE AREA. A BIT MORE OF A NORTHEAST COMPONENT WILL LINGER ALONG THE CHARLESTON COUNTY COAST IN THE WAKE OF A WEAK BACKDOOR FRONT...BUT EVEN DIRECTIONS THERE SHOULD TURN MORE ONSHORE JUST BEFORE SUNRISE THURSDAY. WINDS WILL REMAIN LESS THAN 10 KT WITH SEAS 1-2 FT NEARSHORE WATERS...2-3 FT OFFSHORE WATERS. THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL REMAIN THE DOMINANT FEATURE THURSDAY INTO FRIDAY. SOUTH/SOUTHWEST WINDS WILL INCREASE FRIDAY AS THE PRESSURE GRADIENT TIGHTENS AHEAD OF AN APPROACHING COLD FRONT...HOWEVER CONDITIONS WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. THE FRONT WILL CROSS THE WATERS EARLY SATURDAY...FOLLOWED BY HIGH PRESSURE THROUGH EARLY NEXT WEEK. WINDS THROUGH THE PERIOD WILL GENERALLY BE 15 KT OR LESS...WITH SEAS 2-4 FEET ON AVERAGE. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST/MS
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
214 PM EDT WED APR 20 2016 .SYNOPSIS... A DIFFUSE FRONT ACROSS THE AREA WILL CONTINUE TO WEAK TONIGHT. INCREASING MOISTURE AND A COLD FRONT WILL MOVE THROUGH FROM THE WEST LATE THURSDAY THROUGH EARLY SATURDAY...BRINGING A CHANCE OF SHOWERS AND A FEW THUNDERSTORMS...MAINLY DURING FRIDAY AFTERNOON AND EVENING. DRY HIGH PRESSURE WILL BUILD BACK INTO THE REGION LATE SATURDAY THROUGH TUESDAY. TEMPERATURES EXPECTED TO BE AT OR ABOVE NORMAL. && .NEAR TERM /THROUGH TONIGHT/... A COLD FRONT MOVING INTO THE SOUTHERN MIDLANDS IS EXPECTED TO STALL. PRECIPITABLE WATER WAS BELOW ONE INCH EARLY THIS AFTERNOON. HIGH RESOLUTION MODELS SHOW A LIGHT INCREASE IN PRECIPITABLE WATER ACROSS THE PEE DEE REGION. BOTH THE HRRR AND RAP13 SHOW A FEW SHOWERS DEVELOPING OVER THE PEE DEE REGION LATE THIS AFTERNOON. WILL CONTINUE WITH POPS BELOW 20 PERCENT. MAINLY THIN HIGH LEVEL CLOUDS WILL CONTINUE ACROSS THE AREA. AFTERNOON HIGHS IN THE UPPER 70S NORTH TO MID 80S SOUTH LOOK REASONABLE. STALLED SURFACE FRONT WILL REMAIN ACROSS THE REGION TONIGHT. DRY FORECAST TONIGHT AS INSTABILITY WEAKENS. CONSENSUS INDICATE OVERNIGHT LOWS IN THE MID 50S TO AROUND 60. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... EARLY MORNING LOW CLOUDS THURSDAY SHOULD MIX OUT BY MID MORNING. SURFACE PRESSURE RIDGE OFFSHORE WILL EXTEND INTO THE AREA THROUGH THE DAY. ALSO...UPPER LEVEL RIDGE OVER THE AREA SHIFTING EAST ALONG THE COAST LATE IN THE DAY. EXPECT LIMITED SHOWERS DUE TO AIR MASS STILL RELATIVELY DRY AND SUBSIDENCE EXPECTED. UPPER LEVEL TROUGH OVER THE MISSISSIPPI VALLEY MOVING EAST TOWARD OHIO VALLEY THURSDAY NIGHT. INCREASING SOUTHWEST FLOW SHOULD RESULT IN MOISTURE INCREASE FROM THE WEST/PRECIPITABLE WATER INCREASE 1.25 TO 1.5 INCHES BY MORNING. MOS POPS INCREASE AFTER MIDNIGHT. A FEW SHOWERS MAY DEVELOP OR MOVE IN FROM THE WEST TOWARD FRIDAY MORNING. UPPER TROUGH MOVING THROUGH THE EASTERN CONUS FRIDAY WILL DRIVE COLD FRONT TOWARD THE REGION. AIR MASS BECOMES WEAKLY TO MODERATELY UNSTABLE BY AFTERNOON. MODELS SUGGEST SOME SHOWERS EARLY IN THE DAY THEN ANOTHER SHOT IN THE AFTERNOON. CONVECTION IN THE MORNING AND EXTENSIVE CLOUDS MAY LIMIT DEGREE OF INSTABILITY LATER IN THE DAY. STRONGER CONVECTION MORE LIKELY WEST OF THE REGION BACK IN NORTHWEST GEORGIA WHERE SHEAR STRONGER. DECREASING POPS FRIDAY NIGHT INTO SATURDAY MORNING AS FRONT MOVES THROUGH THE AREA. 850MB TROUGH OFF THE COAST EARLY SATURDAY AND EXPECT DRIER AIR ADVECTION SO CUT POPS BACK FROM PREVIOUS FORECAST DURING THAT PERIOD. MOS TEMPERATURES THROUGH THE PERIOD SEEM REASONABLE ALTHOUGH FAVOR SLIGHTLY HIGHER TEMPERATURES DURING THE DAY DUE TO BIAS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... DRY HIGH PRESSURE TO SETTLE INTO THE SE CONUS LATE SATURDAY THROUGH MONDAY. MOISTURE INCREASE MID WEEK AND ANOTHER FRONT POSSIBLY MOVING SOUTH FROM THE NORTH MAY LEAD TO ISOLATED OR SCATTERED AFTERNOON SHOWERS TUESDAY AND WEDNESDAY. TEMPERATURES SHOULD BE AT OR ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... HIGH CONFIDENCE FOR VFR CONDITIONS THROUGH THIS EVENING. A WEAK COLD FRONT OVER CENTRAL SOUTH CAROLINA EXPECTED TO STALL ACROSS THE AREA TONIGHT. WINDS LESS THAN 10 KNOTS...BECOMING EAST TO SOUTHEAST THIS AFTERNOON. HIGH CLOUDS WILL CONTINUE TO STREAM OVER THE REGION AS WEAK UPPER RIDGING CROSSES THE AREA. MODELS INDICATE LOW LEVEL MOISTURE INCREASING OVERNIGHT. STILL SOME MODEL DISCREPANCY AS TO WHERE IFR CIGS WILL DEVELOP. MODEL CONSENSUS INDICATE LOW CLOUDS DEVELOPING ACROSS THE MIDLANDS...AFFECTING OGB/CAE/CUB BETWEEN 03Z AND 13Z. GIVEN LOW CONFIDENCE...HAVE INDICATED SCT CLOUDS AROUND 1000 FEET. THERE IS ALSO THE POTENTIAL FOR FOG TO DEVELOP AT AGS GIVEN MOIST SOUTHEAST LOW LEVEL FLOW. EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE LATE THURSDAY NIGHT THROUGH EARLY SATURDAY AS A COLD FRONT CROSSES THE REGION. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1226 PM CDT WED APR 20 2016 .SHORT TERM... 329 AM CDT THROUGH TONIGHT... THIS AFTERNOON AND EVENING WILL BRING THE HIGHEST CHANCE FOR SHOWERS IN THE FORECAST AREA IN TEN DAYS. WE HAVE KEPT THE MAIN THEME OF RAIN TIMING BEING MID- AFTERNOON THROUGH EVENING SPREADING FROM WEST TO EAST AND JUST REFINING THAT TO THE HOURLY LEVEL. DID INCREASE THE THUNDER POTENTIAL SOME OVER THE ILLINOIS PART OF THE CWA THOUGH THE RISK FOR SEVERE WEATHER REMAINS QUITE LOW. THE PERSISTENT LARGE UPPER LOW IS GYRATING ITS WAY SLOWLY EAST THIS MORNING WITH ITS CENTER NOW OVER THE CENTRAL PLAINS. A 90 KT UPPER JET ROUNDING THE SOUTHERN EDGE OF THIS CENTER AND ASSOCIATED DEEP PV ANOMALY THIS MORNING WILL HELP RE-DEEPEN THE LOW CENTER BY THIS EVENING OVER IOWA. UPPER FORCING AND ASSOCIATED LIFT IN ADVANCE OF THIS...ALONG WITH A LOW-LEVEL RESPONSE OF THETA-E ADVECTION...WILL SPREAD OVER ILLINOIS DURING THE AFTERNOON. GIVEN THIS WILL BE DURING THE PEAK HEATING TIME...EXPECT THAT THERE WILL BE AN INCREASE IN SHOWER AND STORM ACTIVITY...LIKELY JUST WEST OF THE CWA ALONG THE SYSTEM COLD FRONT DURING THE EARLY TO MID AFTERNOON AND SPREADING EAST FROM THERE. CONVECTIVE ALLOWING MODELS SUCH AS THE HRRR INDICATE THIS INCREASE AND TIMING...THOUGH HAVE VARIED QUITE A BIT FROM RUN-TO-RUN ON THE COVERAGE. A FEW THINGS COULD INDEED LIMIT AFTERNOON SHOWER/STORM COVERAGE SUCH AS THE NARROW NATURE OF THE DEEP MOIST PLUME WRAPPING NORTHWARD INTO THIS SYSTEM. OVERALL THOUGH EXPECT THE AFOREMENTIONED FORCING JUST AHEAD OF THE SYSTEM DRY SLOT TO BE ENOUGH TO PROVIDE AN UPTICK IN SHOWERS DURING THE AFTERNOON INTO EARLY EVENING...WARRANTING LIKELY WORDING IN THE FORECAST. THE INSTABILITY MAGNITUDES /A FEW HUNDRED J/KG/ ARE BETTER FOR THUNDER THAN PREVIOUS FORECAST CYCLES...MAINLY FOR THE NORTH CENTRAL ILLINOIS PART OF THE FORECAST AREA. THE TIMING OF THE MAIN SHOWER AND POSSIBLE THUNDERSTORM AREAS APPEAR TO BE EARLY ENOUGH TO PREVENT DEEPER INSTABILITY RETURN TO LEVELS THAT WOULD WARRANT A THREAT FOR SEVERE STORMS...THOUGH A FEW STRONG ONES WITH MAYBE SOME SMALL HAIL ARE POSSIBLE INTO THE WESTERN CWA WITH FREEZING LEVELS A LITTLE BELOW 10KFT. IN TERMS OF TEMPERATURES...THE FRONTAL BOUNDARY WHICH BROUGHT A 30 DEGREE TEMPERATURE GRADIENT ACROSS THE CWA YESTERDAY...IS NOW DRAPED OVER CENTRAL ILLINOIS TO SOUTHERN INDIANA. THIS WILL LIFT NORTHWARD AS A WARM FRONT TODAY. THE FRONTAL PROGRESSION WILL PROBABLY NOT BE FAR AHEAD OF RAIN SHOWER ACTIVITY WHICH MAKES THE TEMPERATURE FORECAST CHALLENGING. NORTHERN AREAS WILL CERTAINLY BE WARMER THAN YESTERDAY BUT HOW MUCH SO WILL DEPEND ON THE FRONTAL PASSAGE TIMING. ONSHORE FLOW A GOOD PART OF THE DAY FROM CHICAGO NORTHWARD WILL KEEP LAKESIDE TEMPERATURES COOLER AGAIN. FAR SOUTHERN AREAS HAVE THE CHANCE AGAIN TO REACH UPPER 70S. AS THE SYSTEM DRY SLOT WORKS OVERHEAD LATE THIS EVENING INTO OVERNIGHT...THE SHOWER ACTIVITY WILL PUSH NORTHEAST. THE LOW-LEVEL COOL ADVECTION WILL ACTUALLY WEAKEN GIVEN THE OVERALL OCCLUDED NATURE OF THIS SYSTEM...SO LOWS LOOK TO REMAIN IN THE 50S AREAWIDE. MTF && .LONG TERM... 329 AM CDT THURSDAY THROUGH TUESDAY... THE PRIMARY UPPER LOW WILL GRADUALLY TRANSITION INTO AN OPEN WAVE THROUGH THURSDAY AND THURSDAY NIGHT AND SHOULD DO SO AS IT TRACKS EASTWARD OVER THE FORECAST AREA. WHILE DRY AIR ALOFT WILL PREVENT MUCH FOR SHOWERS THURSDAY MORNING...MOST MODEL GUIDANCE INDICATES THE FORECAST AREA TO BE IN A FAVORABLE AREA OF UPPER SUPPORT TO AT LEAST SEE AFTERNOON AND EARLY EVENING SCATTERED SHOWERS AND EVEN A FEW STORMS AGAIN. WITH TEMPERATURES THURSDAY AFTERNOON WARMING BACK INTO THE MID 60S TO LOW 70S...THERE SHOULD BE A FEW HUNDRED J/KG OF CAPE TO WORK WITH. LOWER FREEZING LEVELS COULD PROVIDE A FEW SMALL HAIL PRODUCERS. BEHIND THIS TROUGH FRIDAY AND SATURDAY CONTINUE TO LOOK DRY. STOUT NORTHEAST WINDS ON FRIDAY WILL KEEP LAKESHORE HIGHS INCLUDING DOWNTOWN CHICAGO LIKELY SHY OF 50 DEGREES. INLAND AREAS ARE PRESENTLY FORECAST FOR HIGHS IN THE UPPER 50S/LOWER 60S...ALTHOUGH THIS WILL DEPEND ON CLOUDS CLEARING FRIDAY MORNING. GIVEN THE PRESENT AMPLIFIED/SEMI-BLOCKED PATTERN ACROSS THE EASTERN PACIFIC AND CONUS...CONFIDENCE IN THE LONGER TERM PATTERN EVOLUTION REMAINS LOW. A MASSIVE UPPER LOW/TROUGH IS EXPECTED ACROSS EASTERN CANADA AND THIS WILL PROVIDE NORTHWEST FLOW INTO THE GREAT LAKES...WHILE AN UPPER LOW OVER THE SOUTHWEST U.S. IS ANTICIPATED TO SLOWLY WORK ITS WAY EAST. TOGETHER THESE SHOULD DEVELOP A WEST-TO-EAST BAROCLINIC ZONE ACROSS THE MIDWEST THOUGH WHERE AND HOW ACTIVE REMAINS HIGHLY UNCERTAIN ON MODELS. THIS ALSO LEADS TO LOW CONFIDENCE IN TEMPERATURE FORECASTS AS A LARGE RANGE IS LIKELY ACROSS THIS BOUNDARY. RIGHT NOW HAVE FAVORED A BLEND OF THE EC/GFS/GEM...WHICH BRINGS THE BOUNDARY INTO THE AREA MONDAY AND JUST SOUTH BY TUESDAY. MTF && .AVIATION... FOR THE 18Z TAFS... AN UPPER LEVEL LOW TRAVERSING THE REGION WILL BRING SHOWERS AND A CHANCE OF THUNDERSTORMS TO THE REGION FROM MID/LATE THIS AFTERNOON THROUGH LATE THIS EVENING. A LEADING WAVE OF SHOWERS IS CURRENTLY LIFTING ACROSS PORTIONS OF CENTRAL ILLINOIS AND SHOULD ARRIVE AROUND MID AFTERNOON TO THE CHICAGO/ROCKFORD TERMINALS. INITIALLY DRY CONDITIONS AND VERY WEAK INSTABILITY IN PLACE WILL LIKELY RESULT IN SOME VIRGA WITH ONLY WIDELY SCATTERED SHOWERS MID TO LATE THIS AFTERNOON. WILL HANDLE LOWER PROBABILITY OF SHOWERS ON STATION BY CARRYING A VCSH DURING THIS TIME FRAME. NEXT WAVE OF PRECIP WHICH IS LIFTING ACROSS THE MISSISSIPPI RIVER EARLY THIS AFTERNOON WILL ARRIVE LATE THIS AFTERNOON OR EARLY EVENING AND EXPECT BETTER COVERAGE OF SHOWERS AND POSSIBLY AN ISOLATED THUNDERSTORM OR TWO. THE UPPER LOW WILL FINALLY MOVE OVERHEAD THURSDAY AFTERNOON/EVENING BRINGING ADDITIONAL CHANCES FOR SHOWERS AND THUNDERSTORMS. OUTSIDE OF THE INFLUENCE OF SHOWERS...WINDS WILL CONTINUE OUT OF THE SOUTHEAST FOR THE REST OF TODAY WITH SOME GUSTS NEAR OR SLIGHTLY ABOVE 20 KT POSSIBLE. WINDS WILL DIMINISH LATE THIS EVENING AND TONIGHT AND VEER TO THE SOUTH AND EVENTUALLY SOUTHWEST AS A WARM FRONT LIFTS ACROSS THE REGION. A PERIOD OF MVFR CIGS IS POSSIBLE AROUND THE TIME THE FRONT LIFTS THROUGH...THEN SHOULD RETURN TO VFR AS WINDS INCREASE OUT OF THE SOUTHWEST THURSDAY. BMD && .MARINE... 228 AM CDT A WEAK AREA OF LOW PRESSURE IS EXPECTED TO MOVE EASTWARD OVER LAKE MICHIGAN ON THURSDAY. AS THIS LOW MOVES OVER THE LAKE...LIGHT WINDS AND A MOIST AIR MASS COULD PRODUCE A PERIOD OF FOG OVER THE LAKE. HOWEVER...NORTHERLY WINDS ARE EXPECTED TO INCREASE FROM NORTH TO SOUTH OVER THE LAKE THURSDAY NIGHT INTO FRIDAY FOLLOWING THE EASTWARD PASSAGE OF THE SURFACE LOW. THIS SHOULD RESULT IN A PERIOD OF 30 KT NORTHERLY WINDS ON FRIDAY BEFORE WINDS ABATE FRIDAY NIGHT AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS OVER THE UPPER GREAT LAKES. LARGE WIND WAVES...LIKELY IN EXCESS OF 5 FEET ON SOUTHERN LAKE MICHIGAN WILL RESULT IN OUR NEXT PERIOD OF SMALL CRAFT ADVISORY CONDITIONS FOR THE ILLINOIS AND INDIANA NEAR SHORE WATERS. OVER THE WEEKEND ANOTHER COLD FRONT IS EXPECTED TO SHIFT SOUTHWARD DOWN LAKE MICHIGAN. THERE IS STILL UNCERTAINTY ON THE EXACT TIMING OF THIS FRONT. HOWEVER...THERE ARE INDICATIONS THAT ANOTHER PERIOD OF STRONGER NORTH-NORTHEASTERLY WINDS WILL SET UP OVER THE LAKE POSSIBLY BY LATE SUNDAY OR MONDAY. THIS WILL BE ANOTHER PERIOD TO WATCH FOR POSSIBLE SMALL CRAFT CONDITIONS ON THE NEAR SHORE WATERS DUE TO WINDS AND HIGH WAVES. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1215 PM EDT WED APR 20 2016 .SYNOPSIS... HIGH PRESSURE WILL BUILD ACROSS THE REGION TODAY THROUGH THURSDAY. LOW PRESSURE WILL CROSS THE AREA FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... 1215 PM UPDATE...WINDS AND SKY NEEDED ADJUSTMENTS PER THE LATEST SATELLITE AND OBS. MORE CLOUDS ACROSS THE NORTHERN 1/2 OF THE CWA W/CAA TODAY. NW WIND/DOWNSLOPE AIDING IN KEEPING LESS CLOUDS FOR THE SOUTHERN 1/2 OF THE CWA. SPEAKING OF THE NW WINDS, INCREASED THEM A BIT MORE INCLUDING GUSTS TO 25 MPH. LATEST HRRR 3KM MODEL SHOWED WINDS DROPPING OFF LATER THIS AFTERNOON AS HIGH PRES PUSHES E. PREVIOUS DISCUSSION... QUIET WEATHER IS EXPECTED ACROSS THE REGIONTODAY AS HIGH PRESSURE SETTLES OVER THE NORTHEASTERN CONUS. CLOUDS WILL GRADUALLY DISSIPATE THROUGH THE DAY WITH EVERYONE SEEING SUNSHINE BY LATE AFTERNOON. HIGHS WILL BE SIMILAR TO YESTERDAY. DECENT MIXING TO 6-7 KFT WILL ALLOW WINDS TO BE A LITTLE BREEZY THIS AFTERNOON, AS WELL AS LOWERING DEWPOINTS INTO THE UPPER TEENS AND LOWER 20S. THE WINDS AND LOW RELATIVE HUMIDITY RAISE SOME FIRE WEATHER CONCERNS, BUT WON`T REACH RED FLAG LEVELS. A SPECIAL WEATHER STATEMENT MAY BE NEED TO BE ISSUED LATER TODAY. FOR TONIGHT...DRY WEATHER CONTINUES. MODELS INDICATE THERE`LL BE SOME MOISTURE STREAMING IN AROUND THE TOP OF THE UPPER RIDGE OVERNIGHT, SO MID-LEVEL CLOUDS WILL INCREASE FOR A BIT TONIGHT. LOWS WILL BOTTOM OUT AROUND 30 IN THE NORTH AND IN THE LOWER TO MID 30S SOUTH. && .SHORT TERM /THURSDAY THROUGH FRIDAY/... THU LOOKS TO BE WARM AND DRY AS DOWNSLOPING WNW SFC WINDS BRINGS A A SIG WARM-UP IN THE 925-850MB LAYER...ALLOWING ALL NON-HIGH TRRN AND NON-IMMEDIATE COASTAL AREAS OF THE FA TO REACH WELL INTO THE 60S AND EVEN ARND 70 DEGREES OVR CNTRL AND WRN INTERIOR DOWNEAST LCTNS. SKIES WILL REMAIN FAIR THU EVE...THEN BEGIN TO INCREASE CLDNSS FROM THE W LATE TNGT AFT THE 500MB RIDGE CROSSES THE FA AND WEAK SFC LOW PRES AND S/WV ENERGY FROM BOTH THE MIDWEST AND S CNTRL CAN BEGIN TO APCH THE FA. TEMPS WILL WARM SOMEWHAT WITH FILTERED MORN SUNSHINE...THEN STABILIZE IN THE AFTN BY 5 TO 10 DEG COOLER THAN THU`S HI TEMPS WITH THE ARRIVAL OF SHWRS INTO THE FA. SIX HRLY QPFS LOOK TO BE LGT...WITH PERHAPS A LITTLE MORE IN THE W CNTRL PTNS OF THE FA INCLUDING UP TO BAXTER ST PARK IN THE FRI 18-24Z TM FRAME... JUSTIFYING LOW END CATEGORICAL MAX POPS OVR THIS AREA BY LATE FRI AFTN...WITH LESSER POPS FURTHER N AND E. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... MOST LONGER RANGE MODELS CONT SHWRS OVR THE FA INTO THE EVE... THEN MOVE SHWRS E OF THE REGION LATE FRI NGT AND ERLY SAT MORN AS A COLD FRONT CROSSES THE FA. FCST QPF AMTS IN THE SAT 00-06Z ARE ALSO RELATIVELY LIGHT FOR MOST MODELS...XCPT THE 00Z DTMNSTC GFS WHICH INDICATES 0.35 TO 0.85 INCHES FOR THIS PD. NOT SURE WHATS DRIVING THIS AMOUNT OF QPF IN THE DTMNSTC GFS MODEL IN THE 00-06Z TM FRAME...BUT IN ADDITION TO NOT BEING SUPPORTED BY THE OTHER DTMNSTC 00Z MODELS...IT IS NOT BEING BACKED BY THE 00Z GFS ENSM QPF WHICH ONLY SHOWS 0.10 TO 0.20 INCHES WITH ONLY A COUPLE OF INDIVIDUAL ENS MEMBERS SUGGESTING QPF IN THE 0.25 TO 0.50 INCH RANGE. BASED ON THIS DISCREPANCY...WE DID RAISE POPS INTO THE LIKELY CATEGORY FRI EVE INTO OVRNGT FOR ALL XCPT THE FAR NW PTN OF THE FA THINKING THAT A LITTLE MORE ORGANIZED RNFL IS POSSIBLE WHERE WE INDICATE LIKELY POPS...BUT NOT CONVINCED OF MDT TO HVY RNFL ATTM WITH PLENTY OF TM STILL AVAILABLE FOR BETTER MODEL CONSENSUS FROM THE GFS PRIOR TO THE EVENT ENTERING THE NEAR TERM. OTHERWISE...SAT INTO SAT NGT LOOKS TO BE FAIR...BREEZY... DRY AND COOLER BEHIND THE FIRST COLD FRONT. A SECONDARY COLD FRONT WILL BRING CLOUDINESS TO THE REGION BY SUN AFTN AND ISOLD TO SCT RN/SN SHOWERS WITH VERY LGT QPF TO THE REGION SUN EVE. COLDER AIR AND ACCOMPANIED BY BRISK AND MSLY DRY CONDITIONS WILL FOLLOW FOR MON INTO TUE AS A DEEP MID LVL VORTEX SLIDES INTO THE NRN CAN MARITIMES WITH SIG BELOW NORMAL HIGH TEMPS AND SLIGHTLY BELOW AVG OVRNGT LOWS. && .AVIATION /16Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR WILL PREVAIL TODAY AND TONIGHT WITH NO PRECIPITATION EXPECTED. SHORT TERM: VFR CONDITIONS XPCTD ACROSS THE TAF SITES THU INTO FRI MORN...WITH CLGS AND VSBYS POTENTIALLY LOWERING TO MVFR IN SCT TO NUMEROUS SHWRS ADVCG EWRD FROM QB FRI AFTN INTO THE OVRNGT. CONDITIONS SHOULD IMPROVE BACK TO VFR ON SAT BEHIND THE COLD FRONT AND THEN CONT SO THRU SUN. && .MARINE... NEAR TERM: A SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 11 AM THIS MORNING. WINDS WILL INCREASE THROUGH THE EARLY MORNING HOURS IN RESPONSE A WEAK FRONTAL PASSAGE. GUSTS AROUND 25 KT AND WAVES OF 2 TO 4 FT ARE EXPECTED. CONDITIONS WILL IMPROVE DURING THE AFTERNOON AS HIGH PRESSURE BUILDS OVER THE WATERS. SHORT TO LONG TERM: NO WELL DEFINED PERIODS OF SCA OR GREATER CONDITIONS ARE XPCTD ATTM THRU THESE PTNS OF THE COASTAL WATERS FCST. KEPT CLOSE TO WW3 WV GUIDANCE FOR FCST WV HTS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS JACKSON MS
430 PM CDT WED APR 20 2016 .DISCUSSION...A COLD FRONT CONTINUES TO PUSH SLOWLY TOWARD THE REGION WITH THE BOUNDARY NOW BACK IN THE ARKLATEX AND HEADED THIS WAY. HOWEVER...THE MAIN BAND OF SHOWERS AND THUNDERSTORMS (NOW COMING INTO WESTERN PORTIONS OF THE FORECAST AREA) IS BEING TRIGGERED BY A WEAK SURFACE TROUGH RUNNING OUT A DECENT WAYS IN ADVANCE OF THE FRONT. REGIONAL RADARS REVEAL A FEW ROBUST CELLS WITH A FAIR AMOUNT OF LIGHTNING AND HEAVY DOWNPOURS APPROACHING THE MS RIVER...AND ONLY ISOLATED CELLS BETWEEN THE MS RIVER AND I-55. FORTUNATELY...ATMOSPHERIC INSTABILITY IS NOT HIGH AND WIND SHEAR IS REALLY INSUFFICIENT TO ORGANIZE STORMS INTO MODES THAT WOULD BE MORE WORRISOME FOR SEVERE WEATHER. EXPECTING ALL THIS ACTIVITY TO CONTINUE TO TREND EAST THROUGH THIS EVENING...WORKING INTO THE I-55 CORRIDOR BY EARLY THIS EVENING. LATEST HIRES HRRR RUNS STILL SUGGEST A WEST TO EAST GRADIENT OF FUEL (MOISTURE ADVECTION AND INSTABILITY) CATALYZING STORMS WILL DROP OFF QUICKLY EAST OF I-55...SO EXPECT LATER THIS EVENING THAT CONVECTION WILL HAVE A VERY DIFFICULT TIME GETTING MUCH INTO EASTERN MS. HOWEVER...I AM SLIGHTLY WORRIED THAT THE EXPECTED STALLING NORTH TO SOUTH AXIS OF CONVECTION NEAR THE I-55 CORRIDOR LATER THIS EVENING COULD BE THE FOCUS FOR MORE REDEVELOPMENT LATER TONIGHT AS GULF MOISTURE ADVECTION INCREASES SOMEWHAT (IN TANDEM WITH INVIGORATING LOW LEVEL JET). SUCH A SCENARIO COULD POTENTIALLY BRING HEAVY RAIN WORRIES LATER TONIGHT INTO EARLY TOMORROW INTO PLAY A LITTLE FURTHER EAST THAN WE WERE PREVIOUSLY ANTICIPATING...BUT FOR NOW WE WILL CONTINUE TO KEEP THE MAIN LIMITED RISK OF HEAVY RAIN ISSUES LATE TONIGHT INTO TOMORROW CONFINED TO WESTERN ZONES. THIS LATTER AREA SHOULD THEORETICALLY EXPERIENCE THE BEST LIFT AND MOISTURE ADVECTION THROUGH THIS TIME IF MESOSCALE INFLUENCES FROM INCOMING WEAK MCS DOES NOT OVERLY BIAS THE SYNOPTIC SETUP. ONCE AGAIN...THE RISK OF SEVERE STORMS THROUGH TONIGHT AND EARLY TOMORROW LOOKS TOO LOW TO MENTION IN THE HWO OR GRAPHICS...BUT THERE MAY BE A WINDOW TOMORROW AFTERNOON FOR IMPRESSIVE CAPE (MLCAPE NEAR 2000 J/KG) TO BUILD AS THE FRONT ITSELF PUSHES CLOSER TO THE REGION. AGAIN...SHEAR SHOULD REMAIN VERY MARGINAL FOR MUCH ORGANIZATION TO STORMS...BUT THE EVEN MARGINAL INSTABILITY MAY PUSH AN ISOLATED STORM OR TWO TO SEVERE LIMITS IF CAPE VALUES REALLY MANAGE TO PEAK UP TO (OR ABOVE) THE PREVIOUSLY MENTIONED LEVEL. STILL DO NOT HAVE QUITE ENOUGH CONFIDENCE TO ISSUE AN OFFICIAL LIMITED RISK FOR SEVERE STORMS IN THE HWO/GRAPHICS...BECAUSE IT IS MORE LIKELY MOST STORMS WILL NOT DO MORE THAN PRODUCE BRIEF GUSTY WINDS...SMALL HAIL...FREQUENT LIGHTNING...AND HEAVY DOWNPOURS. OF COURSE WE WILL MONITOR CLOSELY FOR ANY NEEDED ADJUSTMENTS TO THIS THINKING. THE MEAT OF THE UPPER DISTURBANCE DRIVING MOVEMENT OF THE INCOMING FRONT WILL START TRANSITIONING TO OUR EAST THURSDAY NIGHT...BUT THE FRONT REALLY LOOKS TO DRAGS ITSELF INTO THE REGION VERY SLOWLY AS THE IMPETUS FOR MOVEMENT ALOFT IS REALLY FOCUSED WELL TO OUR NORTH. IT IS POSSIBLE THE TAIL END OF THIS FRONT COULD CONTINUE TO KICK UP A FEW SHOWERS OR STORMS THROUGH FRIDAY (ESPECIALLY ACROSS CENTRAL AND EASTERN MS) DESPITE LIFT ALOFT REALLY WEAKENING QUICKLY. BUT THE FRONT SHOULD GET OUT OF THE WAY BY THE WEEKEND...LEAVING DECENT AND WARM CONDITIONS AT THE RIGHT TIME. A WEAK DISTURBANCE SLIDING INTO THE LOWER MS VALLEY ON MONDAY MAY KICK UP A FEW MORE SHOWERS...AND MAYBE A STORM...SUNDAY NIGHT INTO MONDAY BUT BY THIS TIME THE BULK OF ENERGY SHOULD START TO SHIFT NORTH AND NORTHWEST OF OUR AREA. THIS ENERGY INFLUX INTO THE PLAINS AND MID MS VALLEY NEXT WEEK COULD SPELL SOME STORMY TIMES FOR THEM AND WE WILL HAVE TO WATCH ANOTHER ROUND OR TWO OF MODEL RUNS TO FIGURE OUT IF THIS STORMINESS MIGHT NOT SAG INTO AT LEAST NORTHERN PORTIONS OF THE FORECAST AREA FOR A FEW DAYS NEXT WORK WEEK. OTHERWISE...EXPECT A TREND TOWARD TYPICAL LATE SPRING WARMTH. /BB/ && .AVIATION...SHOWERS AND THUNDERSTORMS ARE MOVING EAST INTO AREA AND WERE EXPECTED TO IMPACT GLH AROUND 21Z. MUCH OF THE ACTIVITY WAS EXPECTED TO REMAIN WEST UNTIL LATE THIS AFTERNOON...SO GWO/GLH/HKS AND JAN WOULD BE IMPACTED BETWEEN 23 AND 4Z. WHILE IT WAS MOSTLY RAIN...THUNDERSTORMS WERE BRIEFLY REDUCING VISIBILITIES TO A MILE OR LESS AND CEILINGS WERE BEING LOWERED. ADDED A TEMPO GROUP FOR +TSRA FOR JAN THIS EVENING...NOT TOTALLY SOLD THAT THUNDERSTORMS WILL EXPAND THAT FAR EAST. MODELS SUGGEST A FEW STORMS MAY APPROACH HBG THIS EVENING...BUT LEFT TS OR VCTS OUT AT THIS POINT. STILL EXPECTING FOG TO DEVELOP AGAIN TONIGHT FOR HBG...SO KEPT MVFR AND ADDED A TEMPO FOR LIFR CONDITIONS. FOG HUNG ON FOR A WHILE THIS MORNING AND CONDITIONS WILL NOT BE MUCH DIFFERENT IN THE MORNING. IMPACTS GTR/MEI SEEM TO BE MINIMAL AT THIS TIME./7/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 62 79 61 78 / 64 74 61 30 MERIDIAN 56 78 61 77 / 20 60 68 45 VICKSBURG 62 80 60 80 / 66 64 51 22 HATTIESBURG 60 79 62 78 / 19 51 60 43 NATCHEZ 63 79 61 80 / 69 62 48 26 GREENVILLE 62 78 60 79 / 58 62 50 16 GREENWOOD 63 79 59 78 / 81 65 61 23 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ BB/7/19 Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 405 PM CDT WED APR 20 2016 .Discussion... Issued at 313 PM CDT WED APR 20 2016 For most of the forecast area, the rain this morning cleared out early this afternoon. Within the last hour or so, reflectivity has lit back up along a boundary currently laid out vertically across eastern MO. However, this very broken, thin line of precip is already on the very eastern edge of the forecast area with nothing else currently popping up on radar. As for the cloud cover, other than some occasional breaks, they`re here to stay through tomorrow night. Surface low currently in western IA responsible for the cloud cover and precip will be relatively slow to exit out of the area. Parent upper low will finally phase with the larger scale pattern by the end of the week, allowing for a progressiveness of the weather, but not before periodic rain chances persist through tomorrow. Upper-level ridging will then briefly take control into the weekend, allowing for dry conditions and warming temps. Precip chances will once again enter back into the forecast area Sunday as a low pressure system crosses the Upper Plains. What will need to be monitored is the timing of the associated frontal boundary late Sunday as there may be enough instability and shear to work with to allow the opportunity for storms to become feisty. Stay tuned as the models hone in better on this system, then focus will shift to the next low right on its heels by the middle of next week. Looks to be another unsettled week ahead. Temperatures wise, as already alluded to, highs will warm back into the 70s by this weekend, flirting with perhaps some 80s on Sunday. Temps will then moderate by the start of the next work week with near or slightly above normal temps anticipated through the forecast period. && .Aviation...(For the 18Z TAFS through 18Z Thursday Afternoon) Issued at 1242 PM CDT WED APR 20 2016 MVFR ceilings have been hanging on into the early afternoon hours but is anticipated to finally rise by mid-afternoon. For most of the overnight hours at the four terminals, ceilings should be in the VFR category before dropping back down in the pre-dawn hours on Thursday. For this TAF issuance, have indicated MVFR ceilings but is not out of the realm of possibilities to dip down into the IFR category tomorrow morning, which may need to be included in subsequent forecasts. Look for the winds to remain primarily out of the W-SW. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...lg Aviation...lg
  [top] Area Forecast Discussion National Weather Service Saint Louis MO 338 PM CDT WED APR 20 2016 .SHORT TERM... (Through Late Tonight) Issued at 337 PM CDT Wed Apr 20 2016 Widespread showers are moving through the area this afternoon ahead of a strong vortmax on the eastern side of the upper level low over Nebraska. 850mb winds have turned to the southwest ahead of this system bringing plenty of moisture up from the southeast Plains and lower Mississippi Valley. There is a wind shift to the west from about 850mb to the surface forecast to come through the area tonight, and this wind shift should cut off much of the low level moisture which will shut off the precip as it passes. This should happen west of the Mississippi river by 06Z and through our eastern CWFA by 10-12Z Thursday. There is another shot at more convection on Thursday as the cold core of the upper low moves across northern portions of the area. Lapse rates steepen nicely and there will be another low level trof to provide lift. Not sure right now how much convection there will be, but it`s certainly worth chance PoPs...especially over northern portions of the area. Carney .LONG TERM... (Thursday through Next Wednesday) Issued at 337 PM CDT Wed Apr 20 2016 Upper level low will open up and finally shift east of the region Thursday night with the associated surface low dragging a cold front southeastward through our forecast area. There may be lingering showers, mainly east of the Mississippi River Thursday evening, but the precipitation should shift completely east of the forecast area by late Thursday night. The NAM model has some light QPF for southwest IL on Friday, but it looks a little too far west with the upper level trough compared to the GFS and ECMWF models. For now will keep the forecast dry for Friday, although there should be some low level cloud cover at least over the eastern portion of the forecast area. Cooler temperatures can be expected Friday night due to a clearing sky with surface ridging extending from the Great Lakes region southwest into MO. A warming trend will begin on Saturday due to upper level ridging over the region, and as surface/low level winds become southeasterly/southerly as the surface/850 mb ridge shifts east-southeast of the region. Temperatures by Sunday should be about 10-15 degrees above normal for late April. Precipitation will return to our area Sunday night as an upper level low or trough moves eastward through the northern Plains while an associated surface low drags a cold front southeastward into our area. The GFS is stronger or deeper with the upper level low and surface low compared to the ECMWF model and is more progressive with the front. For now will keep chance pops going for Monday through Tuesday, although if the GFS model solution turns out to be correct there should be a break in the precipitation during this period as surface ridging builds southward into the area behind the cold front. The ECMWF model has convection continuing across parts of the area during this period as the cold front sags only slowly southward through our forecast area. Precipitation should ramp up across the area Tuesday night into Wednesday as another upper level low moves into the Plains and a warm front approaches. GKS && .AVIATION... (For the 18z TAFs through 18z Thursday Afternoon) Issued at 1247 PM CDT Wed Apr 20 2016 Areas of showers and isolated thunderstorms with associated MVFR and potentially IFR flight conditions will move northeast across the area this afternoon. Showers should diminish and move east of the region this evening leaving an isolated shower or two possible overnight. CIG/VIS trends are low confidence tonight as some partial clearing is possible. If this occurs, there will likely be fog...tho again this is low confidence. Specifics for KSTL: Area of showers will impact the terminal early this afternoon bringing MVFR CIGS/VSBYS. Expect conditions to improve after the rain ends later this afternoon...though timing of the improvement is uncertain. CIG/VIS trends are low confidence tonight as some partial clearing is possible. If this occurs, there will likely be fog...tho again this is low confidence. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 338 PM CDT WED APR 20 2016 .SHORT TERM... (Through Late Tonight) Issued at 337 PM CDT Wed Apr 20 2016 Widespread showers are moving through the area this afternoon ahead of a strong vortmax on the eastern side of the upper level low over Nebraska. 850mb winds have turned to the southwest ahead of this system bringing plenty of moisture up from the southeast Plains and lower Mississippi Valley. There is a wind shift to the west from about 850mb to the surface forecast to come through the area tonight, and this wind shift should cut off much of the low level moisture which will shut off the precip as it passes. This should happen west of the Mississippi river by 06Z and through our eastern CWFA by 10-12Z Thursday. There is another shot at more convection on Thursday as the cold core of the upper low moves across northern portions of the area. Lapse rates steepen nicely and there will be another low level trof to provide lift. Not sure right now how much convection there will be, but it`s certainly worth chance PoPs...especially over northern portions of the area. Carney .LONG TERM... (Thursday through Next Wednesday) Issued at 337 PM CDT Wed Apr 20 2016 Upper level low will open up and finally shift east of the region Thursday night with the associated surface low dragging a cold front southeastward through our forecast area. There may be lingering showers, mainly east of the Mississippi River Thursday evening, but the precipitation should shift completely east of the forecast area by late Thursday night. The NAM model has some light QPF for southwest IL on Friday, but it looks a little too far west with the upper level trough compared to the GFS and ECMWF models. For now will keep the forecast dry for Friday, although there should be some low level cloud cover at least over the eastern portion of the forecast area. Cooler temperatures can be expected Friday night due to a clearing sky with surface ridging extending from the Great Lakes region southwest into MO. A warming trend will begin on Saturday due to upper level ridging over the region, and as surface/low level winds become southeasterly/southerly as the surface/850 mb ridge shifts east-southeast of the region. Temperatures by Sunday should be about 10-15 degrees above normal for late April. Precipitation will return to our area Sunday night as an upper level low or trough moves eastward through the northern Plains while an associated surface low drags a cold front southeastward into our area. The GFS is stronger or deeper with the upper level low and surface low compared to the ECMWF model and is more progressive with the front. For now will keep chance pops going for Monday through Tuesday, although if the GFS model solution turns out to be correct there should be a break in the precipitation during this period as surface ridging builds southward into the area behind the cold front. The ECMWF model has convection continuing across parts of the area during this period as the cold front sags only slowly southward through our forecast area. Precipitation should ramp up across the area Tuesday night into Wednesday as another upper level low moves into the Plains and a warm front approaches. GKS && .AVIATION... (For the 18z TAFs through 18z Thursday Afternoon) Issued at 1247 PM CDT Wed Apr 20 2016 Areas of showers and isolated thunderstorms with associated MVFR and potentially IFR flight conditions will move northeast across the area this afternoon. Showers should diminish and move east of the region this evening leaving an isolated shower or two possible overnight. CIG/VIS trends are low confidence tonight as some partial clearing is possible. If this occurs, there will likely be fog...tho again this is low confidence. Specifics for KSTL: Area of showers will impact the terminal early this afternoon bringing MVFR CIGS/VSBYS. Expect conditions to improve after the rain ends later this afternoon...though timing of the improvement is uncertain. CIG/VIS trends are low confidence tonight as some partial clearing is possible. If this occurs, there will likely be fog...tho again this is low confidence. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
  [top] Area Forecast Discussion National Weather Service Springfield MO 221 PM CDT WED APR 20 2016 .SHORT TERM...(This evening through Thursday morning) Issued at 220 PM CDT Wed Apr 20 2016 Scattered showers and a few rumbles of thunder have been observed today across the eastern Ozarks, ahead of a weak frontal boundary that is passing through the area. That front will sweep east through the rest of this evening, with some clearing and advection of dry air in its wake. Will need to watch fog potential across southern/south central Missouri tonight, where rain fell and skies may clear just long enough for patchy ground fog to form. Any clearing will be fairly short lived however, as another lobe of vorticity rounds the base of the upper low toward sunrise. This will likely result in renewed cloud cover and set the stage for additional shower chances Thursday morning. .LONG TERM...(Thursday through Wednesday) Issued at 220 PM CDT Wed Apr 20 2016 Showers and a few isolated rumbles of thunder will again be possible across portions of the Ozarks during the day Thursday as the slow moving upper level low finally swings northeast of the region taking the clouds and rain with it. Upper level ridging will replace the departing system and bring very pleasant conditions to the region for Friday and into early Sunday afternoon with afternoon highs climbing into the 70s. A strong and quick moving storm system will begin to move into the region late Sunday afternoon into the evening hours bringing return chances for showers and thunderstorms through early Monday morning. A quick moving shortwave ridge will move over the region for Tuesday followed quickly by another storm system that will bring more rain and storm chances to the area late Tuesday night through Wednesday. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1213 PM CDT Wed Apr 20 2016 MVFR to IFR cigs early this afternoon should improve heading into the latter portion of this afternoon and this evening. Rain chances will remain widely scattered, with little significant impact expected where it does occur. Winds will be westerly. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Boxell LONG TERM...Hatch AVIATION...Boxell
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 123 PM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 18z TAFs through 18z Thursday Afternoon) Issued at 1247 PM CDT Wed Apr 20 2016 Areas of showers and isolated thunderstorms with associated MVFR and potentially IFR flight conditions will move northeast across the area this afternoon. Showers should diminish and move east of the region this evening leaving an isolated shower or two possible overnight. CIG/VIS trends are low confidence tonight as some partial clearing is possible. If this occurs, there will likely be fog...tho again this is low confidence. Specifics for KSTL: Area of showers will impact the terminal early this afternoon bringing MVFR CIGS/VSBYS. Expect conditions to improve after the rain ends later this afternoon...though timing of the improvement is uncertain. CIG/VIS trends are low confidence tonight as some partial clearing is possible. If this occurs, there will likely be fog...tho again this is low confidence. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1247 PM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 18Z TAFS through 18Z Thursday Afternoon) Issued at 1242 PM CDT WED APR 20 2016 MVFR ceilings have been hanging on into the early afternoon hours but is anticipated to finally rise by mid-afternoon. For most of the overnight hours at the four terminals, ceilings should be in the VFR category before dropping back down in the pre-dawn hours on Thursday. For this TAF issuance, have indicated MVFR ceilings but is not out of the realm of possibilities to dip down into the IFR category tomorrow morning, which may need to be included in subsequent forecasts. Look for the winds to remain primarily out of the W-SW. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...lg
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1247 PM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 18Z TAFS through 18Z Thursday Afternoon) Issued at 1242 PM CDT WED APR 20 2016 MVFR ceilings have been hanging on into the early afternoon hours but is anticipated to finally rise by mid-afternoon. For most of the overnight hours at the four terminals, ceilings should be in the VFR category before dropping back down in the pre-dawn hours on Thursday. For this TAF issuance, have indicated MVFR ceilings but is not out of the realm of possibilities to dip down into the IFR category tomorrow morning, which may need to be included in subsequent forecasts. Look for the winds to remain primarily out of the W-SW. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...lg
Area Forecast Discussion National Weather Service Springfield MO 1217 PM CDT WED APR 20 2016 ...Aviation Update... .SHORT TERM...(Today through Thursday) Issued at 250 AM CDT Wed Apr 20 2016 The upper level low that has been anchored out west the past few days will begin an eastward track the next couple of days as it opens up. A lead shortwave will lift north of the area today while a weak front pushes east across the area. Isolated to scattered showers will continue across the area today. However with the primary lifting mechanism tracking north of the area the potential for a widespread soaking rain is diminishing. The lack of instability will result in limited development of thunderstorms. The potential for a few showers will continue tonight and Thursday as the primary upper level trough axis makes its way across the region. Overall confidence in the short term forecast is high. .LONG TERM...(Thursday through Tuesday) Issued at 250 AM CDT Wed Apr 20 2016 A warming trend along with more sunshine will return Friday into the weekend in the wake of the exiting upper level trough. Upper level ridging and southerly winds will help to push high temperatures well into the 70s to near 80 degrees. A more active weather pattern will return next week as a series of disturbances track eastward across the region. However, forecast certainty of the details in regards to precipitation timing and coverage remain low. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1213 PM CDT Wed Apr 20 2016 MVFR to IFR cigs early this afternoon should improve heading into the latter portion of this afternoon and this evening. Rain chances will remain widely scattered, with little significant impact expected where it does occur. Winds will be westerly. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Boxell
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 621 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 12z TAFs through 12z Thursday Morning) Issued at 612 AM CDT Wed Apr 20 2016 Area of MVFR ceilings from left over convection to our west last night will continue to spread east and lift throughout the morning. Forecasting the cloud base at VFR level by the time it reaches St. Louis Metro later this afternoon. This may be too optomistic and will need to be monitored. Otherwise...some scattered showers and thunderstorms are expected to develop this afternoon across mainly eastern Missouri and Illinois. Some potential for fog tonight if sky can clear and wind decreases. Specifics for KSTL: Light showers will impact terminal the next few hours with a better chance of showers and thunderstorms developing this afternoon. MVFR ceilings to the southwest are expected to lift to VFR level by the time they advect over the terminal. Could see some fog develop late tonight if sky can clear and wind decreases. CVKING && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 620 AM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 12Z TAFS through 12Z Thursday Morning) Issued at 620 AM CDT WED APR 20 2016 Surface low over northeast KS will track into southeast NE over the next couple of hours, taking most rainfall with it and also bringing winds around from the southwest. This wind shift will enter far western MO between 8 AM and 9 AM. A few scattered showers possible through the morning, otherwise slowly improving conditions with clouds becoming scattered VFR later this morning and afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 620 AM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 12Z TAFS through 12Z Thursday Morning) Issued at 620 AM CDT WED APR 20 2016 Surface low over northeast KS will track into southeast NE over the next couple of hours, taking most rainfall with it and also bringing winds around from the southwest. This wind shift will enter far western MO between 8 AM and 9 AM. A few scattered showers possible through the morning, otherwise slowly improving conditions with clouds becoming scattered VFR later this morning and afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion National Weather Service Springfield MO 558 AM CDT WED APR 20 2016 ...Update to Aviation Discussion for 12Z TAFS... .SHORT TERM...(Today through Thursday) Issued at 250 AM CDT Wed Apr 20 2016 The upper level low that has been anchored out west the past few days will begin an eastward track the next couple of days as it opens up. A lead shortwave will lift north of the area today while a weak front pushes east across the area. Isolated to scattered showers will continue across the area today. However with the primary lifting mechanism tracking north of the area the potential for a widespread soaking rain is diminishing. The lack of instability will result in limited development of thunderstorms. The potential for a few showers will continue tonight and Thursday as the primary upper level trough axis makes its way across the region. Overall confidence in the short term forecast is high. .LONG TERM...(Thursday through Tuesday) Issued at 250 AM CDT Wed Apr 20 2016 A warming trend along with more sunshine will return Friday into the weekend in the wake of the exiting upper level trough. Upper level ridging and southerly winds will help to push high temperatures well into the 70s to near 80 degrees. A more active weather pattern will return next week as a series of disturbances track eastward across the region. However, forecast certainty of the details in regards to precipitation timing and coverage remain low. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 557 AM CDT Wed Apr 20 2016 For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will occur early this morning and gradually improve this morning with VFR conditions expected by this afternoon. Fog will also impact the KBBG TAF site early this morning. A cold front will spread east across the area later this morning. A few showers will be possible along the front, but the better chances for rain will be to the north of the area, so left rain out of the TAFS. Winds will be out of the southeast ahead of the front with winds becoming westerly behind the front this afternoon. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Wise
Area Forecast Discussion National Weather Service Saint Louis MO 348 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 348 AM CDT WED APR 20 2016 .SHORT TERM... (Today and Tonight) Issued at 324 AM CDT Wed Apr 20 2016 A large swath of showers and some thunderstorms extended from eastern KS into eastern OK around midnight. This activity was in part due to a well-defined short wave trof rotating through the central Plains. Since that time the swath has fragmented and weakened considerably with the main concentration of precipitation across northeast KS and southeast NE. Further south the coverage of precipitation in advance of the short wave trof consisted of small bands and scattered showers. I think this is what we will mainly see this morning as the short wave continues to rotate to the northeast across the area. In the wake of this morning activity, additional showers and thunderstorms, possibly a broken line, are expected to develop around mid afternoon across eastern MO along/ahead of the advancing cold front pushing then push across SW/SC IL in the evening. Glass .LONG TERM... (Tonight through Tuesday) Issued at 314 AM CDT Wed Apr 20 2016 The upper low/trof currently centered in western NE will evolve into a mobile positively tilted trof by Thursday. A cold pocket aloft will contribute to weak instability, peaking with diurnal heating, and will support scattered primarily afternoon and early evening showers and thunderstorms along a secondary cold front. The threat of precipitation will wane with the loss of heating and passage of the upper trof axis Thursday evening, and yet another cold front from the north will move through the area from late Thursday night though Friday morning. High pressure will then build into the region on Friday in the wake of this later front and dominate through early Saturday. Retreating high pressure on Saturday will allow return flow and WAA to get underway on Saturday afternoon. By Sunday, temperatures will back around the 80 degree mark as ridging aloft builds into the area and south- southwesterly low level flow/WAA is well established. Beyond Sunday there is a good deal of diversity in the model solutions leading to low confidence in details. It does however appear that next week will feature at least one period of stormy conditions more typical of spring. Glass && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 302 AM CDT WED APR 20 2016 ...Chance of Showers Continues into Thursday then a Warmer Weekend... .SHORT TERM...(Today through Thursday) Issued at 250 AM CDT Wed Apr 20 2016 The upper level low that has been anchored out west the past few days will begin an eastward track the next couple of days as it opens up. A lead shortwave will lift north of the area today while a weak front pushes east across the area. Isolated to scattered showers will continue across the area today. However with the primary lifting mechanism tracking north of the area the potential for a widespread soaking rain is diminishing. The lack of instability will result in limited development of thunderstorms. The potential for a few showers will continue tonight and Thursday as the primary upper level trough axis makes its way across the region. Overall confidence in the short term forecast is high. .LONG TERM...(Thursday through Tuesday) Issued at 250 AM CDT Wed Apr 20 2016 A warming trend along with more sunshine will return Friday into the weekend in the wake of the exiting upper level trough. Upper level ridging and southerly winds will help to push high temperatures well into the 70s to near 80 degrees. A more active weather pattern will return next week as a series of disturbances track eastward across the region. However, forecast certainty of the details in regards to precipitation timing and coverage remain low. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overnight. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 301 AM CDT WED APR 20 2016 .Discussion... Issued at 301 AM CDT WED APR 20 2016 A large area of rain tracking across northeast KS this morning is in response to a sharply-negatively tilted shortwave trough tracking through the area, and associated cyclogenesis occurring over northeast Kansas. Both of these features will track into southern Iowa by mid- to late-morning, taking the bulk of precipitation with them. However, a few lingering showers and isolated storms are possible through the afternoon, mainly across northern and central MO where a weak front will be tracking through. Shear along the front will be a bit higher today, so shouldn`t be supportive of the weak landspouts that we`ve seen across parts of Missouri the past couple of days. Large upper low will begin shifting east of the area as an open wave late tonight into Thursday as it phases with the northern jet stream. Scattered showers are possible late tonight and into Thursday as this system passes through with the highest chances across northern Missouri. Low-level ridging building in behind this system will finally bring an end to precipitation chances altogether Thursday evening. Broad upper-level ridging will build into much of the central U.S. Friday and Saturday, keeping dry weather through most of the weekend while temperatures gradually climb to near 80 degrees by Sunday. This ridge will flatten by Sunday afternoon, setting the stage for more active weather heading into next week as another deep upper trough takes shape to the west. This trough will likely send several rounds of precipitation into the region next week, some of which may need to be watched for the potential for strong/severe storms. && .Aviation...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1156 PM CDT TUE APR 19 2016 Rain is currently moving north and will have likely spread across all the west Missouri terminals by 1 AM. Current CIGs are in the MVFR range, though up stream obs show some IFR conditions under the heavier rain. Expect activity to persist through sunrise as a little surface low spins up and moves northeast Wednesday pushing the storms off to north while allow surface winds to continue veering around to the west by early afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Cutter
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1156 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 06Z TAFS through 06Z Wednesday Night) Issued at 1156 PM CDT TUE APR 19 2016 Rain is currently moving north and will have likely spread across all the west Missouri terminals by 1 AM. Current CIGs are in the MVFR range, though up stream obs show some IFR conditions under the heavier rain. Expect activity to persist through sunrise as a little surface low spins up and moves northeast Wednesday pushing the storms off to north while allow surface winds to continue veering around to the west by early afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...Cutter
Area Forecast Discussion National Weather Service Springfield MO 1150 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overinght. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Springfield MO 1150 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1147 PM CDT Tue Apr 19 2016 Still playing the IFR/MVFR game tonight with TAFS. Ceilings have been up and down all evening and should settle in with mostly IFR during the overinght. Not real hip on rain chances outside of JLN and have gone with mainly VCSH wording early on. Models show most of precipitation over northwest MO late tonight as energy lifts northeast with the slow moving upper low. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 1149 PM CDT TUE APR 19 2016 .UPDATE... Issued at 939 PM CDT Tue Apr 19 2016 Area of rain/embedded thunderstorms should continue to slowly weaken and drift northward overnight tonight. Do not expect much if any in the way of activity after midnight tonight. Next round of at least scattered showers/storms will try and move north/northeast from south-central/southeast Missouri early Wednesday morning. Adjusted PoPs for the rest of tonight and also raised low temperatures a couple of degrees in most locations due to high dewpoints and clouds. Gosselin && .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 06z TAFs through 06z Wednesday Night) Issued at 1144 PM CDT Tue Apr 19 2016 Expect rest of tonight to be dry across terminals as rain/storms have weakened and are dissipating currently across northeastern Missouri. Some fog possible...particularly at KSUS and KCPS with at least a partially clearing sky and low T/Td spreads. IFR visbys not out of the question but for now went MVFR. Thinking there should be enough clouds at KCOU and KUIN to preclude fog development but this will have to be watched as well. Still expecting some scattered showers and possibly a few storms to affect metro terminals late Wednesay morning. Additional scattered activity along/ahead of cold front will carry a higher threat of thunder during the afternoon hours. By Wednesday evening...threat of showers/storms should push off to the south and east of the terminals with winds beginning to veer to the southwest as front slowly moves through the bi-state area. Specifics for KSTL: Expecting dry/VFR conditions for rest of tonight. High T/Td spread expected to prevent fog prevention. Scattered showers/possibly a storm may affect terminal late morning. Then another break before another round of showers/storms develops along/ahead of cold front late afternoon. By Wednesday evening...threat of showers/storms should push off to the east. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated National Weather Service Saint Louis MO 941 PM CDT TUE APR 19 2016 .UPDATE... Issued at 939 PM CDT Tue Apr 19 2016 Area of rain/embedded thunderstorms should continue to slowly weaken and drift northward overnight tonight. Do not expect much if any in the way of activity after midnight tonight. Next round of at least scattered showers/storms will try and move north/northeast from south-central/southeast Missouri early Wednesday morning. Adjusted PoPs for the rest of tonight and also raised low temperatures a couple of degrees in most locations due to high dewpoints and clouds. Gosselin && .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 726 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 00z TAFs through 00z Wednesday Evening) Issued at 643 PM CDT Tue Apr 19 2016 Main area of showers and thunderstorms along a frontal boundary may affect the KUIN and KCOU terminals over the next couple of hours. Showers and storms should gradually wane overnight with most of the area dry. Area of showers and embedded storms look to come toward the metro terminals Wednesday morning. Another round along the actual cold front may affect all of the terminals during the afternoon and possibly into the early evening hours. Ceilings will also lower to MVFR on Wednesday as low-level moisture increases. Specifics for KSTL: Expect a dry night with VFR conditions. Round of showers/embedded storms expected to move in from south/southwest Wednesday morning. Another round of showers/storms along cold front for Wednesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 641 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 00Z TAFS through 00Z Wednesday Evening) Issued at 641 PM CDT TUE APR 19 2016 VFR conditions this evening are not expected to last as showers will move northeast across the region late tonight into Wednesday morning. Low end MVFR to IFR CIGs will spread across the terminals around midnight along with scattered showers that will persist until around sunrise Wednesday. Winds will veer around overnight to the south, southwest and finally west by Wednesday afternoon as the center of a small surface low, that brought the showers, moves northeast through northwest Missouri. CIgs will likely go back to VFR for the afternoon. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...Cutter
Area Forecast Discussion National Weather Service Springfield MO 600 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 557 PM CDT Tue Apr 19 2016 Pesky upper level low underneath blocking omega pattern still sitting off to the west. Scattered showers will remain in the terminals and mainly keeping in VCSH in the forecast. Main aviation concern again will be with the MVFR/IFR conditions. Will see ceilings lower again tonight, eventually into the IFR category at the 3 terminal locations. Conditions will improve during the day Wednesday, back into MVFR/VFR by late in the day. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Saint Louis MO 340 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late Tonight) Issued at 340 PM CDT Tue Apr 19 2016 Large upper level low spinning over northeast Colorado will begin to move slowly eastward tonight and pick up speed on Wednesday. Several lobes of vorticity will rotate around the low tonight and Wednesday which will continue to keep the threat for precip over the region. I can`t say that there will be any time through 00Z Thursday that is certain to be dry, but at least through mid morning the showers will be more scattered in nature than wide-spread. The showers currently on the scope should dissipate slowly this evening with a few likely popping up at times across the CWFA through the night. Expect increasing Increasing coverage during the late morning and afternoon on Wednesday as 850mb winds veer to the southwest and one of the more prominent vort-lobes rotates through Missouri into Illinois. This combined with the 850mb moisture convergence and the associated surface trof will likely touch off more widespread showers and thunderstorms. Temperatures will be highly dependent on what areas get precipitation. I stuck pretty close to ensemble MOS guidance for lows tonight and highs Wednesday. Carney .LONG TERM... (Wednesday through Next Tuesday) Issued at 340 PM CDT Tue Apr 19 2016 A longwave upper-level RIDGE will dominate the central CONUS thru the upcoming weekend. The wx won`t be typical for a longwave RIDGE, however, because of the presence of a cutoff LOW, that by the time Wednesday night rolls around, will be in the process of being re-absorbed back into the main flow and will be on the move. The models still track the main system center to our north on late Wednesday night and Thursday, leaving only the northern CWA across northern MO and central IL with any measure of upper support for pcpn. There will also be a surface cold front slowly dropping thru Thursday that will maintain lift and focus. So, rain chances will continue easily thru Thursday. The more significant drying of the column and subsequent reduction in rain chances should arrive with passage of the TROF axis late Thursday, but even with this, there is some model discrepancy on timing, with the GEM delaying this until early Friday morning, but the mode amongst the solutions favors late Thursday afternoon or early evening. Temps will temporarily dip back to near normal for late week between the clouds, rain, and brief intrusion of a cooler airmass behind the Thursday front. The departure of the leftover cutoff LOW system which should be by Friday will mean a more typical result for a longwave upper RIDGE-- and back to dry and warm wx for the weekend for most areas once the southerly winds kick back in on Saturday. Daytime max temps should reach near 80F again. The GFS has since backed off its adverisement of a strong upper level system for next Monday, but both the EC and GFS now at least show a favorable setup for what should be a frontal boundary dropping south into our region for late Monday into Tuesday with a supportive flow aloft from the W-NW. So despite losing what would have been good upper support, the signal for rain chances is no less good late Monday and Tuesday than it was 24hrs ago, and largely maintained the at or slightly above average climo PoPs during this period. TES && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 310 PM CDT TUE APR 19 2016 .Discussion... Issued at 310 PM CDT TUE APR 19 2016 Short Term (Today through Thursday night): The main feature of interest in the short term continues to be the upper level low out west. It is centered over northeastern Colorado this afternoon. This low will continue to meander slowly eastward tonight as it remains cut off from the upper level steering flow. It will however take on a negative tilt this evening with an associated vort max rotating around the base of the trough. This will help a surface low to develop across eastern Kansas tonight. This will provide for good forcing and expect showers to develop across eastern Kansas tonight and spread northeastward across the area. Despite good forcing, weak lapse rates and only a couple hundred Joules of CAPE should limit thunderstorm activity however, isolated storms can not be ruled out across northeastern Kansas and northwestern Missouri. Tomorrow the upper level low will move into the vicinity of the Missouri/Iowa border continuing showers and isolated thunderstorm chances generally north of the Missouri River. Cloud cover and precipitation will also keep temperatures in the low to mid 60s across the northern CWA while temperatures across the south will range into the lower 70s. The upper low will continue to remain near stationary tomorrow night and will continue shower chance tomorrow night. Thursday the upper level system finally gets absorbed into the upper level flow north of the area. Residual showers on the back side of the exiting upper level trough will remain possible on Thursday before finally drying out Thursday night as the upper level trough exits the region. Highs Thursday will remain in the mid 60s to lower 70s. Extended Range (Friday through Tuesday): As the upper level system exits the region, upper level ridging over the Rockies will begin to push eastward and begin to build into the local area on Friday. This ridge will remain over the area through Sunday providing warm temperatures for the upcoming weekend. Highs by Sunday will rise into the upper 70s to lower 80s. On Sunday/Sunday night another upper level low will move out from the central Rockies into the northern Plains flattening the upper level ridge and will force a cold front into the eastern Plains. This will bring the next round of showers and thunderstorms to the area late Sunday into Sunday night. Unsettled weather may then continue into the beginning of next week as the upper level low weakens across the northern Plains on Monday leaving the cold front stalled across the CWA Monday into Tuesday continuing shower and thunderstorm chances. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...73 Aviation...73
Area Forecast Discussion National Weather Service Springfield MO 243 PM CDT TUE APR 19 2016 .SHORT TERM...(This evening through Wednesday) Issued at 243 PM CDT Tue Apr 19 2016 The slow moving upper low will continue to move eastward over the next 24 hours and bring the potential for showers and isolated thunderstorms to the Ozarks. Winds across the region will remain southerly with temperatures falling into the 50`s tonight. May need to watch for some very patchy fog again in the morning, but coverage should be rather spotty as rain coverage should be greater than last night. Limited instability and little shear will significantly limit any potential for strong or severe storms through Wednesday. An Isolated rumble of thunder will likely be the most storms can muster despite temperatures climbing into the upper 60s to lower 70s as the upper low begins to lift slowly to the northeast. .LONG TERM...(Wednesday Night through Tuesday) Issued at 243 PM CDT Tue Apr 19 2016 The upper low will continue to make its slow eastward progression Wednesday night through Thursday night with the potential for additional showers and isolated thunderstorms. Despite the cloud cover and rain potential, temperatures will be in the upper 40s into the 50s overnight and in the 70s during the afternoons as we head into the weekend. Upper level ridging will take control of the regions weather for Friday and Saturday with highs climbing into the upper 70s with sunny skies. For the later half of the weekend however, the upper level flow will become more southwesterly which will bring the return for rain and storms chances for late Sunday night into the beginning of next week. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Hatch LONG TERM...Hatch AVIATION...Frye
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 111 PM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more positively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 18z TAFs through 18z Wednesday Afternoon) Issued at 1244 PM CDT Tue Apr 19 2016 A large upper level storm system centered over Colorado is sending waves of smaller disturbances into the Mississippi Valley. Most of the lower ceilings have risen at this time, and I expect VFR ceilings and visibilities to prevail this afternoon and evening. However...isolated to widely scattered showers may temporarily lower the flight category to MVFR or even IFR in the heavier rain. Coverage is uncertain, but best estimate at this time is 20-30 percent. Showers should dissipate slowly this evening after we lose daytime heating. Think lower ceilings will develop again Wednesday morning ahead of the surface trof of low pressure which will move into the area toward the end of the period. Additionally, more showers and probably thunderstorms as well are expected to develop during the mid to late morning. IFR ceilings are possible...but did not want to go that low until confidence improves so have MVFR in all the terminal forecasts for Wednesday morning. Specifics for KSTL: Expect VFR flight conditions to prevail at Lambert this afternoon into the overnight period as well. Widely scattered showers are developing over eastern Missouri. Looks like there are a couple of stronger ones with some lighting in them now too. Unfortunately there really aren`t any easily definable features to try to time any precipitation at Lambert...something could develop over the terminal with little or no warning. Fortunately the majority of the showers should be brief and not particularly heavy. The most likely impact would be a brief period of 3-5SM visibility. Showers should dissipate slowly after sunset. MVFR looks likely tomorrow morning ahead of a surface trof with scattered showers developing after 12Z. Showers and thunderstorms are likely after 17Z. Carney && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 1234 PM CDT TUE APR 19 2016 ...18z Aviation Update... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) Issued at 1234 PM CDT Tue Apr 19 2016 Off and on shower activity can be expected again through this TAF cycle. Visibilities have improved from early this morning, however, ceilings have been behaving a tad erratic. Ceiling heights will be the primary challenge through the next 24 hours as all terminals will alternate between IFR and MVFR conditions at times. There may even been some brief VFR mixed in this afternoon as some breaks in the cloud cover have been observed from time to time on satellite imagery. Fog/low stratus may once again impact the forecast tomorrow, though, the signal isn`t nearly as strong as yesterday`s. Still, enough confidence is there to lower visibilities down to the MVFR range briefly Wednesday morning. Winds will continue to be light and variable through the period. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Frye
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1222 PM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1222 PM CDT TUE APR 19 2016 Bkn MVFR cigs persists ovr NE KS and NW MO so contd MVFR cigs at the TAF sites til 20Z-21Z before lifting to low-end VFR. VFR conds will prevail til tonight when showers will move into the terminals around 06Z-08Z with he chance for heavier showers in the 09Z- 13Z window. Isold thunder will be poss with good forcing but time of day and weak lapse rates should limit thunder chances. Consequently, have left out of TAFs for now. Otrw...expect MVFR cigs/vis tomorrow morning with the potential of IFR cigs/vis btn 09Z-13Z in heavier showers. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...73
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 631 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 12Z TAFS through 12Z Wednesday Morning) Issued at 631 AM CDT TUE APR 19 2016 Most shower activity today will be confined to central and eastern Missouri, with the KC and STJ areas remaining dry for much of the day. MVFR ceilings are gradually lifting to VFR across eastern KS, and expect this trend to continue into western MO through the morning. Widespread rain will overspread the region late tonight. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...Hawblitzel
Area Forecast Discussion...Updated Aviation National Weather Service Saint Louis MO 558 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 12z TAFs through 12z Wednesday Morning) Issued at 549 AM CDT Tue Apr 19 2016 Band of light rain from near KCOU to KUIN will gradually dissipate this morning. Additional light showers and isolated thunderstorms are possible this afternoon...but sparse coverage precludes placing in TAFS. Ceilings will remain in the VFR category...with generally light and variable winds. Specifics for KSTL: Band of light rain this morning should stay west of KSTL metro...and ceilings will likely remain above 7000 feet for the duration of this TAF period. There is a chance for scattered showers and isolated thunderstorms this afternoon...but coverage is expected to remain sparse. Winds will remain light southwest to south. Browning && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 549 AM CDT TUE APR 19 2016 ...Update to Aviation Discussion for 12Z TAFS... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) Issued at 543 AM CDT Tue Apr 19 2016 For the KSGF, KJLN, and KBBG TAFS: IFR ceilings will continue at the KJLN TAF site early this morning, then will improve through the day. Ceilings may lower into the MVFR range at the KSGF and KBBG TAF sites this morning before improving this afternoon. Patchy fog will also occur early this morning, especially at the KBBG site. Showers should remain north and south of the TAF sites through this morning, then scattered showers will be possible this afternoon into tonight across the area. Ceilings are expected to lower into the MVFR to IFR range again tonight into early Wednesday morning. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Wise
Area Forecast Discussion National Weather Service Saint Louis MO 349 AM CDT TUE APR 19 2016 .SHORT TERM... (Through Late This Afternoon) Issued at 323 AM CDT Tue Apr 19 2016 Water vapor imagery depicting a well defined conveyor belt of moisture flowing into the region as a result of deep layered south-southwesterly flow well ahead of the Rockies upper low. An initial low amplitude impulse in the flow aloft is contributing to a broken swath of rain/showers through central and northeast MO. This precipitation should continue a north-northeast movement this morning shunting to the east and gradually weakening. There may be a good bit of downtime then from mid-morning into early afternoon where any precipitation is spotty. However from mid-late afternoon the diffuse boundary and weak convergence zone stretching across central and northeast MO is expected to become the focus for scattered showers and thunderstorms as diurnal heating results in a weakly unstable and uncapped air mass. Glass .LONG TERM... (Tonight through Monday) Issued at 323 AM CDT Tue Apr 19 2016 Showers and thunderstorms originating this afternoon are expected to dissipate by mid-evening once instability wanes and also given the overall weak forcing. Once again there may then be a good deal of dry time with only spotty precipitation until well overnight. At that time a rather prominent short wave trof will begin spreading large scale ascent from western MO into central MO as it rotates northeastward in advance of the slowly migrating upper low. Precipitation chances will ramp-up Wednesday into Wednesday evening as the aforementioned short wave continues to rotate to the northeast producing large scale ascent, as the low level southerly flow/WAA increases, and as the accompanying surface low and frontal system moves into the region. The precipitation threat should then diminish overnight as the upper trof becomes more postively tilted and migratory, and as deeper moisture is transported into the OH/TN Valleys in advance of the advancing surface cold front. There will remain a threat of scattered showers on Thursday in the post-frontal cyclonic flow and until the passage of the upper trof axis to the east. High pressure should dominate on Friday bringing tranquil weather and seasonable temperatures. The high will then begin retreating Saturday bringing some moderation, with a bigger warm-up on Sunday as ridging aloft progresses into the MS valley from the Plains and low level southerly flow/WAA gets well established. Lot of uncertainty beyond Sunday with some large pattern differences amongst the deterministic models and large spreads in the EPS. In general however an increasing threat of stormy conditions seems to be the trend. Glass && .AVIATION... (For the 06z TAFs through 06z Tuesday Night) Issued at 1133 PM CDT Mon Apr 18 2016 Scattered showers will affect KCOU and possibly KUIN through the rest of tonight. Showers should be light and likely not pose visibility issues. For the metro terminals...showers should stay west. Ceilings will also lower at KCOU and KUIN into MVFR later on tonight. Some minor visibility reduction is also possible in fog at KCOU. For Tuesday...highest threat of showers/storms again from KCOU to KUIN with the best chance of convection during the late afternoon and early evening hours. Heavier showers/storms could dip visibilities down briefly into IFR. Metro terminals again likely too far to the east. Specifics for KSTL: Lion`s share of shower/thunderstorm activity expected to stay west of terminal through Tuesday night. However...scattered showers/storms are possible Tuesday afternoon/evening in particular. Continue to leave out prevailing group as chances look higher further to the west. Winds will remain light/variable before turning southeasterly again Tuesday afternoon. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && $$ WFO LSX
Area Forecast Discussion National Weather Service Springfield MO 258 AM CDT TUE APR 19 2016 ...Good Chance for Showers Today through Wednesday... .SHORT TERM...(Today through Wednesday Night) Issued at 245 AM CDT Tue Apr 19 2016 Moist and unsettled weather conditions will be the story the next couple of days as the upper low positioned over the southern Rockies begins a slow eastward progression. Meanwhile a diffuse frontal boundary remain nearly stalled from north central Oklahoma into northern Missouri. A broad region of upper level divergence superimposed over at least weak low level convergence near the front along with a continued moisture advection will support scattered to numerous showers today. After a lull this evening we could see an increase in the coverage of showers later tonight into Wednesday as a shortwave swings northeast from the southern Plains ahead of the upper low. While most everyone will see rainfall the potential for heavy rain has decreased from previous forecast due to the lack of strong deep synoptic scale lift and limited instability. This lack of instability will limit the coverage of thunderstorms with just isolated embedded thunder expected. .LONG TERM...(Thursday through Monday) Issued at 245 AM CDT Tue Apr 19 2016 The upper low will begin to open up and move steadily east during late week. The chance for isolated to scattered showers will linger Thursday as the upper level trough axis swings across the region. Upper level ridging will build into the region heading into Friday and this weekend following the passage of the upper level trough. Building 500 MB heights and return southerly flow will push temperatures well into the 70s if not near the 80 degree mark this weekend. Models continue to show a more unsettled weather pattern returning next week but details yet to be determined. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1132 PM CDT Mon Apr 18 2016 Scattered light showers across the area this evening and have affected the terminal locations with some light rain. While showers will be in the vicinity of the aviation sites tonight and Tue morning, the main concern will be with MVFR and IFR conditions. Will see ceilings deteriorate overnight and may build down enough for visibilities to also be affected. Showers will again become more numerous late in the period as the upper level shortwave to the west slowly approaches. && .SGF Watches/Warnings/Advisories... MO...NONE. KS...NONE. && $$ SHORT TERM...Foster LONG TERM...Foster AVIATION...Lindenberg
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 254 AM CDT TUE APR 19 2016 .Discussion... Issued at 254 AM CDT TUE APR 19 2016 Large closed low slowly drifting into the High Plains remains the main weather story for the next few days, as this system will continue to push several more rounds of rain into the region. For today, a weak cold front is becoming quasi-stationary near the southern and eastern borders of our forecast area, and this feature will be the primary focus for any rainfall through most of the afternoon. This will keep the higher precipitation chances focused across the Clinton/Sedalia areas and then up the US-63 corridor. Areas further west should stay dry most the day with a few peeks of sun possible. Rainfall chances increase significantly later tonight when most models agree that a fairly strong and negatively-tilted shortwave will round the base of the mean upper low and eject into our area. This will likely lead to small-scale cyclogenesis over northeast KS, with resulting lift bringing a large area of rain to eastern KS and western MO late tonight. A focused area of convergence/frontogenesis near the surface low combined with precipitable water values between an inch and an inch and a half could favor some modest rainfall amounts, particularly from eastern KS into northwest MO where some areas could see an inch or more of rain from this system. Most precipitation will taper off Weds afternoon as the surface low tracks into Iowa, though a few showers or storms could linger into central MO along a trailing front. Large upper low will finally begin to push east of the region on Thursday when it will merge with the northern jet stream and phase into a broad, progressive upper wave. A few showers are possible Thursday on the back side of this system, otherwise the departure of the upper low will finally allow for drying conditions heading into Friday and Saturday. Deep upper ridging building in behind this system will bring a warming trend into the weekend with several areas pushing 80 degrees by Sunday. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...Hawblitzel Aviation...MJ
Area Forecast Discussion National Weather Service Kansas City/Pleasant Hill MO 1153 PM CDT MON APR 18 2016 .Discussion... Issued at 332 PM CDT MON APR 18 2016 Water vapor imagery and H5 heights indicate the extensive closed low still positioned over the inter-mountain west with cold front currently moving through eastern Nebraska and Kansas, extending down into the Texas panhandle. At the regional level, band of heavier precip has moved northeastward through the morning and early afternoon, gradually weakening with time as primary forcing remained north across Iowa. Scattered showers remain on the backside of the main band, and the HRRR has done a great job with the overall precip trend. With a few hundred joules of CAPE, might see an isolated thunderstorm or two with this scattered activity. Western half of the CWA should see a downward trend in activity towards evening. Another vorticity maxima will peel off from the main low late tonight into Tuesday morning. Cold front looks to stall across the region from southwest to northeast Missouri. Greater chances for precip will focus near this diffuse cold front and with 600-800 J/kg of CAPE forecast Tuesday afternoon, expect to see thunderstorm development by early afternoon. Showers and thunderstorms expected once again Wednesday in somewhat of a wash-rinse-repeat cycle. Upper low finally begins to eject into the Plains Tuesday night into Wednesday, eventually merging into the northern stream flow. As the trough passes to the north of the region, we could see a few more showers and thunderstorms into Thursday. Upper level ridging will build into the central conus as we head into the weekend, bringing warm temperatures and relatively quiet weather. The next system to watch will be a trough ejecting out of the central Rockies the beginning of the next work week. && .Aviation...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1153 PM CDT MON APR 18 2016 Scattered showers have moved out of west central and northwest MO and will gradually shift east overnight. Extensive area of MVFR ceilings will likely remain intact over northern, west central and central MO overnight. Satellite imagery does show the clearing line over central KS shifting east and projects to reach the MO/KS border around 12z. These clouds will then be replaced by broken VFR ceilings for most of Tuesday. Should start to see scattered convection form or move into west central MO and east central KS by late Tuesday evening. && .EAX Watches/Warnings/Advisories... KS...None. MO...None. && $$ Discussion...PMM Aviation...MJ
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
408 PM CDT WED APR 20 2016 .SYNOPSIS... ISSUED AT 405 PM CDT WED APR 20 2016 H5 ANALYSIS THIS MORNING HAD A CLOSED LOW OVER NORTH PLATTE WITH RIDGING OFF TO THE WEST OVER THE INTERMOUNTAIN WEST INTO THE PANHANDLE OF IDAHO. EAST OF THE LOW...A LOW AMPLITUDE RIDGE OF HIGH PRESSURE EXTENDS FROM THE FLORIDA PANHANDLE NORTH TO THE OHIO VALLEY. HT FALLS THIS MORNING WERE MOST PRONOUNCED ACROSS EASTERN KANSAS AND EASTERN NEBRASKA...WITH 70 METER FALLS NOTED AT OMAHA AND 100 METER FALLS NOTED AT TOPEKA. CURRENT SATELLITE IMAGERY HAS THE LOW NEAR LEXINGTON NEBRASKA WITH A SECONDARY CIRCULATION NOTED AROUND OMAHA. SHOWERS HAVE CONTINUED TO ROTATE AROUND THE NORTHERN AND WESTERN PERIPHERY OF THE LOW TODAY AND HAVE MADE IT AS FAR WEST AS A MERRIMAN TO OGALLALA LINE. OVER THE PAST COUPLE OF HOURS...SOME CONVECTIVE SHOWERS HAVE DEVELOPED OVER SERN LINCOLN AND FRONTIER COUNTIES. ELSEWHERE...A MORE PERSISTENT SHIELD OF RAIN WAS OCCURRING ACROSS THE NEBRASKA SANDHILLS. HOURLY RAINFALL RATES WERE LIGHT...AT OR UNDER 3 HUNDREDTHS OF AN INCH. TEMPERATURES AS OF 3 PM CDT RANGED FROM 51 TO 59 DEGREES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 405 PM CDT WED APR 20 2016 THIS EVENING AND TONIGHT...EXPANDED HIGH CHC POPS WEST TO HWY 83 TO ACCOUNT FOR SCATTERED SHOWERS ROTATING AROUND THE LOW. ALSO EXPANDED ISO THUNDER MENTION FOR SOUTHERN HALF OF THE FORECAST AREA. FORECAST SOUNDINGS SHOW STEEP LOW LEVEL LAPSE RATES AND PERIODS OF SIGNIFICANT LIFT. RAP ANALYSIS ALSO SHOWS MARGINAL CAPE...GENERALLY 500 J/KG OR LESS...LIFTED INDEX AS LOW AS -1... AND MID LEVEL LAPSE RATES NEAR 7C/KM. GIVEN DEEP COLD AIR ALOFT...SMALL HAIL IS POSSIBLE WITH ANY STORM. HRRR AND RAP INDICATE MOST OF THE SHOWER/STORM ACTIVITY OUTSIDE NORTH CENTRAL NEBRASKA WILL BE DIURNALLY DRIVEN. SLOWLY PULL POPS FOR BOYD...HOLT...WHEELER COUNTIES TONIGHT DUE TO THE PROXIMITY OF AN AREA OF STEADY RAIN OVER NORTHEAST NEBRASKA. MADE LITTLE CHANGE TO MIN TEMPS AS PREVIOUS FORECAST LOWS ARE SIMILAR TO 12Z MOS GUIDANCE SUITE...COOLER PANHANDLE AND WEST FOR CLEARING SKY AND LIGHT WINDS AND MILD NORTH CENTRAL FOR SUSTAINED CLOUDINESS. DESPITE RECENT RAINFALL AND LIGHTENING WINDS OVERNIGHT...RISK OF FOG IS LOW. SLIGHTLY DRIER AIR MOVES IN AS SHOWN BY FALLING MIXING RATIOS...AND AS SURFACE WINDS TURN WESTERLY/NORTHWESTER...ITS NOT AS FAVORABLE FOR FOG FORMATION. THURSDAY...H5 LOW SCOOTS EAST INTO IOWA AND THE H3 JET MAX CENTERS OVER THE MISSOURI RIVER. TRENDED MAX TEMPS TOWARD THE MAV...WHICH RESULTED IN AN INCREASE OF A DEGREE OR SO AREAWIDE. NAM SOUNDINGS INDICATE DRY AIR ALOFT...WEAK TO NON EXISTENT LIFT IN THE LOWER LEVELS...AND A MIXED LAYER APPROACH 700HPA. MID LEVEL FGEN FORCING ALSO WEAKENS AS THE LOW MOVES EAST OF THE AREA. WITH MAINLY FAIR CONDITIONS AND UNINHIBITED MIXING...BREEZY NORTH WINDS ARE LIKELY AND H85 TEMPS AROUND 10C SHOULD TRANSLATE TO HIGHS NEAR 70F. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 405 PM CDT WED APR 20 2016 MID RANGE...THURSDAY NIGHT THROUGH SATURDAY...IN THE MID RANGE...A BENIGN WEATHER PATTERN IS EXPECTED IN THE MID RANGE WITH TEMPERATURES BEING THE MAIN FORECASTING CHALLENGE. THE CLOSED LOW WILL TRACK INTO THE OHIO VALLEY THURSDAY NIGHT INTO FRIDAY...WHILE RIDGING ALOFT BUILDS EAST FROM THE CENTRAL ROCKIES INTO THE CENTRAL PLAINS. TEMPERATURES FRIDAY WILL REACH THE LOWER TO MIDDLE 70S...FOLLOWED BY MID 70S TO AROUND 80 FOR SATURDAY. THE LATEST NAM SOLN WAS BEGINNING TO INDICATE A FAVORABLE ENVIRONMENT FOR THUNDERSTORMS SATURDAY AFTERNOON IN THE WEST WITH VERY FAVORABLE SURFACE BASED INSTABILITY AND A DECENT AMOUNT OF SD CAPE. HOWEVER...SHEAR LOOKS WEAK ATTM. THE GFS AND ECMWF SOLNS HOLD OFF ON CONVECTION UNTIL SAT EVENING AND HAVE OPTED TO GO THIS ROUTE AND LEAVE SAT AFTERNOON DRY FOR NOW. BETTER CHANCES FOR PRECIPITATION WILL ARRIVE IN THE WEST SATURDAY EVENING AS A LEAD SHORTWAVE CROSSES THE PANHANDLE. LONG RANGE...SATURDAY NIGHT THROUGH WEDNESDAY...BEGINNING SATURDAY NIGHT...CHANCES FOR PCPN WILL INCREASE IN THE WEST AS A LEAD SHORTWAVE CROSSES THE PANHANDLE. THIS WILL BE FOLLOWED BY A CLOSED LOW WHICH TRACKS ACROSS SRN SD SUNDAY INTO SUNDAY NIGHT. WRAP AROUND PCPN FROM THE SYSTEM WILL IMPACT THE NORTHERN CWA ON SUNDAY AND SUNDAY NIGHT. FURTHER SOUTH...COOLER AND WINDY CONDS ARE EXPECTED SUNDAY...WITH NOT MUCH IN THE WAY OF PCPN EXPECTED. BETTER CHANCES FOR PRECIPITATION WILL ARRIVE MONDAY NIGHT INTO WEDNESDAY AS A SECOND UPPER LOW LEVEL LOW TRACKS FROM THE CENTRAL ROCKIES ONTO THE CENTRAL PLAINS. TEMPERATURES WILL BE MUCH COOLER AS WELL WITH HIGHS IN THE 50S BY MIDWEEK NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 405 PM CDT WED APR 20 2016 SCATTERED LIGHT RAIN SHOWERS WILL CONTINUE THIS AFTERNOON ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT FOR SOUTHWEST NEBRASKA...INCLUDING KLBF... KOGA...KBBW...AND KIML. RAIN SHOWER COVERAGE AND WIND SPEED WILL DECREASE AROUND SUNSET WHILE LOW/MID LEVEL CLOUD COVER WILL THIN OVERNIGHT. && .HYDROLOGY... ISSUED AT 405 PM CDT WED APR 20 2016 RISES EXPECTED TO CONTINUE ON THE SOUTH PLATTE RIVER FOR THE NEXT SEVERAL DAYS DUE TO RECENT PRECIPITATION OVER WESTERN NEBRASKA AND COLORADO. USGS STREAM GAUGE AT ATWOOD CO HAS SHOWN A LEVELING OFF WHILE JULESBURG STILL SHOWS A STEADY RISE. IN COORDINATION WITH THE MBRFC...A FORECAST SHOWS A CREST AROUND 7 FEET LATE FRIDAY AT ROSCOE...WHICH PUTS IT AT ACTION STAGE. NO FLOODING IS EXPECTED AT THIS TIME. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BUTTLER SHORT TERM...SNIVELY LONG TERM...BUTTLER AVIATION...SNIVELY HYDROLOGY...BUTTLER
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
311 PM CDT WED APR 20 2016 .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...SATELLITE AND RADAR IMAGES INDICATE CONVECTION CONTINUING TO DEVELOP ACROSS NORTHEAST MEXICO THIS AFTERNOON AND BOTH THE NAM AND HRRR CONTINUE TO INDICATE CONVECTION DEVELOPING ACROSS EXTREME WESTERN PORTIONS OF THE CWA LATE THIS AFTERNOON INTO THIS EVENING. WITH THE SURFACE INSTABILITY REMAINING HIGH ACROSS THE RIO GRANDE VALLEY AND NORTHERN RANCHLANDS...CANNOT RULE OUT THE POTENTIAL FOR ISOLATED SEVERE THUNDERSTORMS ACROSS PORTIONS OF ZAPATA...JIM HOGG...AND STARR COUNTIES THIS EVENING. THE GREATEST THREAT FOR SEVERE APPEARS TO BE HAIL AND DAMAGING WINDS. HEAVY RAINFALL CAN BE EXPECTED WITH SOME OF THE STRONGER TO SEVERE STORMS. WILL GO WITH THE HIGHEST POPS ACROSS THE WESTERN PORTIONS OF THE CWA WITH LOWER POPS TOWARDS THE COAST THIS EVENING. THE FORECAST FOR THURSDAY AND THURS NIGHT IS CHALLENGING WITH THE WEST TO NORTHWEST FLOW ALOFT BUT THE NAM AND GFS HAVE A CONVECTIVE BOUNDARY DEVELOPING ACROSS PORTIONS OF CENTRAL TX THURSDAY AND AS THIS FEATURE MOVES SOUTHWARD IT WILL PROVIDE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF THE CWA THURSDAY INTO THURS NIGHT AS MOISTURE POOLS ALONG AND AHEAD OF A WEAK COLD FRONT MOVES SOUTHWARD ACROSS SOUTH TX. .LONG TERM /FRIDAY THROUGH WEDNESDAY/...UPPER LEVEL RIDGE WILL BEGINS TO BUILD ACROSS THE DESERT SOUTHWEST INTO S TEXAS FRIDAY WITH A WEAK FRONT MOVING SOUTH. WEAK FRONT COMBINED WITH PERTURBATIONS WITHIN THE FLOW WILL ENHANCE SHOWERS AND THUNDERSTORMS ACROSS THE CWA. THE BOUNDARY WILL STALLED OVER DEEP SOUTH TEXAS WITH WINDS REMAINING EASTERLY INTO SATURDAY. AN ABUNDANT SURGE OF MOISTURE WILL MOVE INTO THE AREA CONTINUING THE DEVELOPMENT OF MORE SHOWERS AND THUNDERSTORMS ACROSS THE WESTERN COUNTIES THIS WEEKEND. MODEL GUIDANCE CONTINUE TO SHOW ABOVE 1.5 IN OF PRECIPITABLE WATER THROUGH THE WEEKEND WHICH WILL FAVOR THE DEVELOPMENT WITH THIS TROUGH AS IT MOVES EASTWARD. DRIER AIR MASS MOVES INTO THE AREA MONDAY WITH LESS SIDE TROUGH DEVELOPING OVER SOUTH CENTRAL TEXAS. THIS WILL LIMIT THE POTENTIAL FOR RAIN BUT A FEW ISOLATED SHOWERS CAN`T BE RULED NEAR THE COAST WITH THE SEABREEZE. THE RIDGE WILL BE IN CONTROL OF THE AREA MONDAY AND TUESDAY LIMITING THE POTENTIAL FOR RAIN THROUGH MID WEEK. THE SOUTHERLY FLOW WILL INCREASE TO MORE BREEZE CONDITIONS MONDAY AS THE NEXT UPPER TROUGH STRENGTHENS OVER THE PAC NORTHWEST. MODELS ARE IN PRETTY GOOD AGREEMENT WITH GFS BEEN SLIGHTLY MORE PROGRESSIVE WITH THE NEXT LOW PRESSURE SYSTEM WHILE THE ECMWF IS A BIT SLOWER. EVEN WITH THE SLIGHT DIFFERENCE STILL SHOW THE POTENTIAL FOR RAIN FOR THE WEEKEND AND THE DRY AIR FILTERING IN BY EARLY NEXT WEEK. LEAN TOWARDS A BLEND OF THE TWO MODELS FOR THIS PACKAGE. && .MARINE...TONIGHT THROUGH THURSDAY NIGHT...SEAS WERE NEAR 4 FEET WITH EAST TO SOUTHEAST WINDS NEAR 10 KNOTS AT BUOY020 EARLY THIS AFTERNOON. LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS TONIGHT INTO THURSDAY WITH LOW PRESSURE ACROSS NORTHEAST MEXICO AND A WEAK COLD FRONT DRAPED ACROSS NORTH TEXAS. THE BOUNDARY WILL MOVE INTO SOUTH TX THURS NIGHT AND THIS WILL CONTINUE TO PROVIDE A WEAK PRESSURE GRADIENT ACROSS THE LOWER TX COAST. FRIDAY THROUGH TUESDAY...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE FOR THE EARLY PORTION OF THE LONG TERM PERIOD AS ABUNDANT MOISTURE IN THE REGION WILL ALLOW FOR CONVECTION TO CONTINUE. EXPECT A MODERATE SOUTHEAST FLOW ACROSS THE GULF WITH SEAS BETWEEN 2 TO 4 FEET THROUGH THE WEEKEND. RIDGE BEGINS TO BUILD LOWERING SEAS EVEN LESS THAN 2 FEET SAT AND SUN. AN INFLUX OF MOISTURE WILL SURGE NORTH SAT NIGHT INTO SUN INCREASING THE CHANCE OF SHOWERS ONCE AGAIN. SEAS WILL BEGIN TO INCREASE INTO MONDAY AS A STRONG SURFACE LOW STRENGTHENS OVER THE CENTRAL PLAINS. SEAS WILL BEGIN TO BUILD TO 3 TO 6 FEET WITH SCEC POSSIBLE. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 72 82 71 80 / 20 20 20 20 BROWNSVILLE 72 85 71 83 / 20 20 20 30 HARLINGEN 71 87 70 84 / 20 20 20 30 MCALLEN 72 90 71 87 / 30 30 20 30 RIO GRANDE CITY 71 92 70 88 / 40 20 30 30 SOUTH PADRE ISLAND 72 78 71 77 / 20 20 20 20 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 61/67
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1247 PM CDT WED APR 20 2016 .AVIATION... STABLE AIR BEHIND EARLY MORNING CONVECTION HAS SETTLED INTO THE AREA. KDRT STILL HAS AN MVFR CIG...BUT CONDITIONS ELSEWHERE ARE MOSTLY VFR. WE EXPECT SOME TSRA TO FORM OVER THE HILL COUNTRY THIS EVENING AND APPROACH THE AUSTIN METRO AREA FROM THE WEST...BUT HAVE LEFT MENTION OUT OF THE TAFS SINCE THE RISK IS LOW. OTHERWISE...EXPECT IFR CIGS AND MVFR VSBYS TO DEVELOP BY 05-07Z AND CONTINUE TO MID-MORNING THURSDAY. ALL MESOSCALE MODELS SHOW ANOTHER QLCS MOVING THROUGH EAST TEXAS THURSDAY MORNING...SO WE PUT VCSH IN THE KSAT/KAUS EXTENDED TAFS TO GIVE INDICATION ON INTENSITY AND TIMING. && .PREV DISCUSSION... /ISSUED 924 AM CDT WED APR 20 2016/ UPDATE... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ALONG AND BEHIND AN OUTFLOW BOUNDARY PUSHING ALONG HIGHWAY 90. A WEAK COLD FRONT IS SLOWLY PUSHING ACROSS THE NORTHERN HILL COUNTRY PER LATEST SURFACE OBSERVATIONS AND SPC MESOSCALE ANALYSIS PAGE. THIS ACTIVITY IS EXPECTED TO CONTINUE THROUGH THE AFTERNOON AS IT SHIFTS TO THE SOUTH AND EAST. BOTH HRRR AND RAP 13 MODELS SHOW A DOWNWARD TREND ON THE SHOWER AND THUNDERSTORM ACTIVITY FOR THE SHORT TERM/FIRST PERIOD. LATEST KEWX RADAR LOOPS SHOW A DECREASE IN THE INTENSITY OF SHOWERS AND STORMS. NEW STORMS DEVELOPMENT ARE POSSIBLE ACROSS THE SOUTHERN EDWARDS PLATEAU AND THE RIO GRANDE AREAS THIS AFTERNOON AS THE TAIL END OF THE WEAK COLD FRONT PUSHES TO THE SOUTH AS IT MEETS WITH THE PASSAGE OF AN UPPER SHORT WAVE. FLASH FLOOD WATCH CONTINUES IN EFFECT THROUGH 1 PM THIS AFTERNOON FOR THE EASTERN COUNTIES OF SOUTH CENTRAL TEXAS (MORE DETAILS ON THIS IN THE WATCHES/WARNINGS/ADVISORIES SECTION). NEW RAINFALL AMOUNTS(NEXT 3 TO 6 HOURS)THROUGH THIS AFTERNOON COULD RANGE FROM 1 TO 2 INCHES ACCORDING TO KEWX DOPPLER RADAR ESTIMATES AND REFLECTIVITY TRENDS. PREV DISCUSSION... /ISSUED 611 AM CDT WED APR 20 2016/ AVIATION... WEAKENING COMPLEX OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE TO TREK SOUTHWARD. WILL BEGIN TAFAUS FOR THE FIRST FEW HOURS WITH -RA PREVAILING BUT WILL TEMPO -TSRA TO COVER THE THREAT FOR THE ISOLATED THUNDERSTORMS. FOR THE SAN ANTONIO SITES...WILL ONLY MENTION VCSH LATER THIS MORNING AS CONFIDENCE IS A BIT LESS THIS SYSTEM MAKES IT THIS FAR SOUTH. CEILINGS ARE PRESENTLY AROUND LOW MVFR OR IFR AND THESE RESTRICTIONS SHOULD REMAIN IN PLACE THROUGH THE EARLY AFTERNOON. ANOTHER ROUND OF MVFR IS EXPECTED TOMORROW NIGHT. BEYOND THIS MORNING...CANT RULE OUT ADDITIONAL ISOLATED OR SCATTERED PRECIPITATION...BUT CHANCES ARE TOO LOW TO MENTION IN THE TAFS AT THIS TIME. PREV DISCUSSION... /ISSUED 359 AM CDT WED APR 20 2016/ SHORT TERM (TODAY THROUGH THURSDAY)... SHOWERS AND THUNDERSTORMS ALONG A WACO TO SAN ANGELO TO BIG LAKE LINE WERE MOVING TO THE SOUTHEAST AT 25 MPH. THE LINE WILL MOVE INTO LLANO AND BURNET COUNTIES BY 5 AM AND THEN SLOW AS IT MOVES FURTHER INTO SOUTH CENTRAL TEXAS. THE LINE/BOUNDARY STALLS ACROSS SOUTH CENTRAL TEXAS LATER TODAY...MOST LIKELY AROUND THE I-10 CORRIDOR. RAINFALL AMOUNTS UP TO 1 TO 2 INCHES ARE POSSIBLE. THIS RAINFALL WILL NOT CAUSE MUCH FLOOD THREAT FOR MOST AREAS. HAVE MAINTAINED THE FLASH FLOOD WATCH EAST OF I-35 THROUGH MIDDAY TODAY AS ANY ADDITIONAL RAIN WILL CAUSE NEW OR AGGRAVATE ONGOING FLOODING IN THOSE AREAS THAT HAVE RECEIVED COPIOUS AMOUNTS OF RAIN SINCE SUNDAY. THERE IS A POTENTIAL THE WATCH COULD BE EXTENDED. LOCALLY HEAVY DOWNPOURS ARE POSSIBLE ALONG AND NEAR THE BOUNDARY THIS AFTERNOON INTO EVENING AND AGAIN ON THURSDAY. CAPES AVERAGING AROUND 2500 J/KG AND 0-6KM SHEAR OF 25 TO 35 KTS INDICATE A MARGINAL RISK OF STRONG TO SEVERE STORMS DURING THE AFTERNOON INTO EARLY EVENING HOURS TODAY AND THURSDAY. HAIL AND STRONG WIND GUSTS ARE THE MAIN THREATS. LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)... THE PESKY UPPER LEVEL LOW OPENS INTO TROUGH ALONG THE MISSISSIPPI VALLEY THURSDAY NIGHT SENDING A WEAK COLD FRONT ACROSS SOUTH CENTRAL TEXAS. SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE FRONT. RIDGING AT THE SURFACE AND ALOFT IS INDICATED FRIDAY AND SATURDAY. THE AIRMASS DRIES AND STABILIZES ACROSS MOST OF SOUTH CENTRAL TEXAS. HOWEVER...A MOIST SOUTHEASTERLY FLOW UP THE RIO GRANDE WILL MAINTAIN LOW CHANCES OF RAIN THERE ON FRIDAY AND SATURDAY. A COMPACT UPPER LEVEL TROUGH DEVELOPS OVER NORTHWESTERN MEXICO ON SATURDAY AND MOVES ACROSS TEXAS ON SUNDAY INTO EARLY MONDAY BRINGING RAIN CHANCES. A FEW MODELS SHOW LOCALLY HEAVY DOWNPOURS. RAIN CHANCES RETURN THE MIDDLE OF NEXT WEEK AS ANOTHER UPPER LEVEL TROUGH TAKES SHAPE OVER THE WESTERN STATES WITH A PACIFIC FRONT/DRYLINE MOVING INTO OUR AREA. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 65 80 61 80 58 / 30 40 30 10 0 AUSTIN BERGSTROM INTL AIRPORT 64 79 60 79 56 / 30 40 30 10 0 NEW BRAUNFELS MUNI AIRPORT 64 80 62 80 58 / 30 40 40 10 0 BURNET MUNI AIRPORT 63 77 57 77 56 / 30 40 20 10 0 DEL RIO INTL AIRPORT 66 85 63 82 64 / 20 30 30 20 10 GEORGETOWN MUNI AIRPORT 63 77 58 78 56 / 30 50 20 10 0 HONDO MUNI AIRPORT 65 82 62 81 60 / 30 40 40 10 0 SAN MARCOS MUNI AIRPORT 64 79 61 79 57 / 30 40 40 10 0 LA GRANGE - FAYETTE REGIONAL 66 79 62 80 57 / 30 50 40 10 0 SAN ANTONIO INTL AIRPORT 66 80 63 80 60 / 30 40 40 10 0 STINSON MUNI AIRPORT 66 82 64 81 61 / 30 40 40 10 0 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...26 SYNOPTIC/GRIDS...17 PUBLIC SERVICE/DATA COLLECTION...TREADWAY
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1245 PM CDT WED APR 20 2016 .AVIATION... LINE OF STORMS ABOUT TO PUSH OFF COAST. LINGERING -RA MAY LINGER FOR A FEW HOURS IN ITS WAKE UNTIL THE WHOLE DISTURBANCE MOVES OUT...BUT CIGS WILL MOVE INTO VFR TERRITORY FAIRLY QUICKLY BEHIND THE LEADING EDGE. MAYBE SOME ISO LATE AFTN CELLS, BUT OVERALL EXPECT A LULL IN SIGNIFICANT WX FOR THE REST OF THE AFTN & EVENING. CIGS MIGRATE BACK DOWN INTO MVFR & IFR OVERNIGHT. ATTENTION TURNS TO N TX LATE TONIGHT WHERE ANOTHER STORM COMPLEX DEVELOPS AND MOVES TOWARD SE TX. SET UP LOOKS SIMILAR TO TODAYS WITH GRADUAL WEAKENING AS IT ARRIVES. TIMING IS UNCERTAIN...BUT ANTICIPATE THE ARRIVAL SOMETIME AFTER SUNRISE CLL...AND HOU METRO AREA TOWARD LATE MORNING. LATER SHIFTS WILL NEED TO FINE TUNE TIMING AND TAFS AS TRENDS ARE ESTABLISHED. 47 && .PREV DISCUSSION... /ISSUED 1018 AM CDT WED APR 20 2016/ WEAKENING LINE OF STORMS WAS PUSHING INTO POLK...SAN JACINTO... MONTGOMERY...HARRIS...FORT BEND...AND COLORADO COUNTIES AT 10 AM. LIGHT RAIN WAS OCCURRING BEHIND THE SYSTEM. THE NAM12 HAS HAD A DECENT HANDLE ON EVENTS SO FAR...AND THE MODEL CLEARS THE SYSTEM OUT BY THE EARLY AFTERNOON. THE RAP AND TEXAS TECH BOTH SHOW SOME SCATTERED REDEVELOPMENT IS POSSIBLE DURING THE MID AND LATE AFTERNOON PERIOD. TRIMMED POPS DOWNWARD FOR THIS AFTERNOON TO ACCOUNT FOR THE LESSENING RAIN CHANCES IN THE MODEL. THE 12Z SOUNDINGS AT KLCH AND KCRP BOTH HAD A PW OF 1.5/1.6 INCHES. RAINFALL AMOUNTS FROM THE RAIN GAUGE NETWORK WITH THE SYSTEM HAS BEEN UNDER A HALF AN INCH...WHILE RADAR HAS SHOWN SOME LOCALIZED 1 INCH TOTALS. THIS POTENTIAL WILL LINGER OVER THE CENTRAL AND COASTAL COUNTIES AHEAD OF THE LINE IN THE FLASH FLOOD WATCH AREA. BECAUSE OF THE LESS EXPECTED COVERAGE IN THE NORTH... HAVE TAKEN OUT WALKER...GRIMES...BRAZOS...AND BURLESON COUNTIES FROM THE FLASH FLOOD WATCH. THE WATCH STILL GOES THROUGH 7 PM THIS EVENING FOR THE REMAINING COUNTIES...AND WILL MAKE A DECISION LATER THIS AFTERNOON ON WHETHER OR NOT TO EXTEND THE WATCH. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 79 67 77 57 79 / 60 30 50 30 10 HOUSTON (IAH) 79 67 80 64 81 / 60 40 70 40 10 GALVESTON (GLS) 75 70 76 69 76 / 50 30 50 30 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING ZONES: AUSTIN...BRAZORIA...CHAMBERS...COLORADO...FORT BEND...GALVESTON...HARRIS...LIBERTY...MONTGOMERY...POLK... SAN JACINTO...WALLER...WASHINGTON...WHARTON. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1208 PM CDT WED APR 20 2016 .MESOSCALE UPDATE... ...SOME SEVERE WEATHER POSSIBLE TODAY IN MAINLY THE SOUTH CENTRAL AND SOUTHEAST TX PANHANDLE... * SYNOPTIC OVERVIEW: WE`LL SEE ONE LAST GASP SHRTWV TROUGH THIS AFTERNOON FROM THE NOW POSITIVELY TILTED UPR LOW THAT HAS CAUSED WEATHER EXCITEMENT AROUND THE AREA THE PAST 5 DAYS. WATER VAPOR ANALYSIS PLACES THE UPR LOW NEAR NORTH PLATTE, NE THIS MORNING WITH THE LOW EXPECTED TO LIFT TO NEAR OMAHA TONIGHT. THE NW FLOW SHRTWV WILL BEGIN TO IMPACT THE AREA EARLY THIS AFTERNOON, QUICKLY CROSSING THE CWA THIS EVENING. ASCENT FROM THE TROUGH AND ASSOC JET STREAK WILL BE ENOUGH TO SPAWN SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON/EVENING. * MESOSCALE: SHEAR PROFILES WILL BE FAVORABLE FOR ORGANIZED CONVECTION THOUGH SOMEWHAT WEAK INSTABILITY (IE MLCAPE VALUES OF MAYBE 300-600 J/KG) SHOULD KEEP THIS FROM BEING A BARN BURNER OF A DAY. NAM MLCAPE PROGS OF 750-1000 J/KG THIS AFTERNOON JUST EAST OF KAMA SEEM TO BE OVERDONE AS THE NAM HAS OVER-ANALYZED THE AMOUNT OF LOW-LVL MOISTURE DOWNSTATE SO FAR THIS MORNING. DO THINK THAT THE HIGHER SIDE OF RAP/HRRR VALUES OF AROUND 500 J/KG MLCAPE COULD BE REALIZED THOUGH GIVEN THE RAPID REDUCTION OF LOW CLOUD COVER SEEN IN LATEST GOES SUPER RAPID SCAN VIS SAT OBSERVATIONS. * THREATS: THE CAPE DISTRIBUTION LOOKS TO MOST FAVOR ISOLATED DOWNBURST WINDS THIS AFTERNOON GIVEN A SOMEWHAT DEEP/DRY SUBCLOUD LAYER. WITH THE PROPENSITY FOR THE STRONGEST UPDRAFTS TO WANT TO ORGANIZE GIVEN THE FAVORABLE SHEAR PROFILE, SVR HAIL TO THE SIZE OF GOLF BALLS CANNOT BE RULED OUT IN STORMS THAT TAKE ON SUPERCELLULAR CHARACTERISTICS. THE TORNADO WINDOW LOOKS SMALL BOTH SPATIALLY AND TEMPORALLY BUT MAY BRIEFLY EXIST FOR AN HOUR EITHER SIDE OF SUNSET FOR A WEAK ISOLATED TORNADO SOMEWHERE IN THE SE PART OF THE TX PANHANDLE. THE RAPID NW TO SE STORM MOTIONS SHOULD PRECLUDE MUCH OF A FLOOD THREAT TODAY. * TIMING & LOCATION: THE BEST CHANCES FOR SEVERE WEATHER THIS AFTERNOON WILL BE IN THE SOUTH CENTRAL AND SOUTHEAST TX PANHANDLE, THOUGH ISOLATED STRONG TO SEVERE WIND GUSTS COULD OCCUR AS FAR NORTH AS DUMAS OR BORGER. AMARILLO WILL BE ON THE WESTERN EDGE OF THE THREAT, BUT A STRONG OR SEVERE STORM CANNOT BE RULED OUT FOR THE CITY. TIMING-WISE, THE BEST WINDOW WILL PROBABLY BE FROM AROUND 5PM-10PM. SIMPSON/LORENZEN .AVIATION...18Z TAFS...MVFR CIG AOA 1500 FT AGL SHOULD GRADUALLY GIVE WAY TO CIG AOA 5K FT AGL IN ADVANCE OF A SHORTWAVE TROUGH. SOUTH TO SOUTHWEST WINDS BTWN 10 TO 20 KTS WILL CONTINUE THRU THE AFTN UNTIL A WEAK COLD FRONT PASSES THROUGH THE REGION AROUND 20/21Z. THIS INCOMING FRONT WILL PROVIDE A FOCUS FOR POSSIBLE SHOWERS AND THUNDERSTORMS BTWN 20/21Z THRU 21/06Z...WITH SOME STORMS CAPABLE OF APPROACHING SEVERE LEVELS DURING THE AFTN HOURS. AS THE FRONT PASSES...WINDS WILL SHIFT TO THE NORTH BTWN 10 TO 20 KTS. VFR CONDITIONS ARE LIKELY AFT 21/06Z AS DRIER AND MORE STABLE AIR MOVES IN BEHIND THE FRONTAL BOUNDARY. BIEDA && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 45 72 45 77 51 / 50 5 0 5 0 BEAVER OK 44 73 43 79 53 / 20 5 0 5 5 BOISE CITY OK 39 71 41 77 50 / 30 5 0 5 5 BORGER TX 46 75 47 79 54 / 50 5 0 5 5 BOYS RANCH TX 43 74 44 79 52 / 40 5 0 5 5 CANYON TX 44 73 44 77 49 / 40 5 0 0 0 CLARENDON TX 48 73 47 77 51 / 70 10 0 5 0 DALHART TX 41 72 42 77 49 / 40 5 0 5 5 GUYMON OK 42 73 43 79 52 / 20 5 0 5 5 HEREFORD TX 45 73 44 77 50 / 30 5 0 0 5 LIPSCOMB TX 46 74 44 78 53 / 30 5 0 5 5 PAMPA TX 45 70 46 77 52 / 60 10 0 5 5 SHAMROCK TX 49 74 46 78 51 / 70 10 0 5 5 WELLINGTON TX 51 76 47 79 51 / 70 10 0 5 0 && .PREV DISCUSSION... /ISSUED 410 AM CDT WED APR 20 2016/ DISCUSSION... TAKING ANOTHER LOOK AT THE LATEST HIGH-RES MODELS...THE HRRR IS NOW BACKING OFF FROM THE DEVELOPMENT OF DENSE FOG ACROSS THE PANHANDLES THIS MORNING. WILL LIKELY TO NEED TO CANCEL BUT WILL HOLD OFF UNTIL CLOSER TO DAYBREAK TO SEE IF ANY DENSE FOG DEVELOPS. IF NOT...WILL CANCEL BEFORE SHIFT CHANGE THIS MORNING. OTHERWISE...LOW CLOUDS WILL PREVAIL THIS MORNING AS THE VIGOROUS CLOSED UPPER LOW OVER THE CENTRAL PLAINS STATES ALLOWS FOR A VORT LOBE TO ROTATE NORTHWEST TO SOUTHEAST ON THE BASAL OF THE UPPER TROUGH BY 00Z TO 06Z THURSDAY ACROSS THE FORECAST AREA. CONVECTION SHOULD DEVELOP AFTER 20Z TO 22Z TODAY...MAINLY OVER THE SOUTHERN HALF OF THE TEXAS PANHANDLE...WITH THE SEVERE THREAT PRIMARILY ACROSS THE SOUTHEASTERN AND SOUTH CENTRAL PORTIONS OF THE TEXAS PANHANDLE LATER TODAY AND TONIGHT. CONVECTION SHOULD QUICKLY EXIT THE PANHANDLES BY 12Z THURSDAY AS AN UPPER RIDGE BUILDS IN FROM THE WEST LATE THIS WEEK. WARMER AND DRIER CONDITIONS EXPECTED THURSDAY THROUGH THE WEEKEND. THE MEDIUM RANGE MODELS DIFFER WITH RESPECT TO THE NEXT CLOSED UPPER LOW PROGGED TO MOVE OUT OF THE GREAT BASIN REGION THIS WEEKEND INTO EARLY NEXT WEEK. THE ECMWF...WHICH WAS THE DRIER MODEL 24 HOURS AGO...IS NOW FORECASTING AN OPEN WAVE TO TRACK NORTHEAST OUT OF BAJA CALIFORNIA AND NORTHWEST MEXICO FRIDAY NIGHT AND SATURDAY INTO SOUTHWEST TEXAS BY SATURDAY NIGHT AND SUNDAY. THE MAIN CLOSED UPPER LOW IS FORECAST TO LIFT EAST AND NORTH OUT OF THE GREAT BASIN REGION INTO THE CENTRAL ROCKIES AND NORTHERN PLAINS STATES BY EARLY NEXT WEEK. THE ECMWF BREAKS OUT QPF SATURDAY AFTERNOON ACROSS THE NORTHWESTERN PORTIONS OF THE FORECAST AREA SATURDAY AFTERNOON BUT KEEPS THE REMAINDER OF THE WEEKEND AND EARLY NEXT WEEK DRY. THE GFS IS COMPLETELY THE OPPOSITE OF 24 HOURS AGO AND IS NOW KEEPING THE CLOSED UPPER LOW OVER THE NORTHERN STREAM RATHER THAN THE SOUTHERN STREAM. THE GFS ALSO FORECASTS AN OPEN WAVE LIFTING NORTH AND EAST OUT BAJA CALIFORNIA AND NORTHWESTERN/NORTHERN MEXICO...HOWEVER THE GFS KEEPS THE QPF WELL SOUTH OF THE PANHANDLES AND...LIKE THE ECMWF...MAINTAINS A DRY FORECAST THROUGH THE END OF THE WEEKEND INTO EARLY NEXT WEEK. THEREFORE...OPTED TO REMOVE POPS FROM SUNDAY AND GO WITH A DRY AND UNSEASONABLY WARM FORECAST THIS WEEKEND INTO EARLY NEXT WEEK. BREEZY TO WINDY THIS WEEKEND AS A DEEPENING SURFACE TROUGH DEVELOPS TO THE LEE OF THE ROCKIES WHICH WILL THEN TRACK EAST INTO THE FORECAST AREA SUNDAY. A COLD FRONT IS FORECAST TO PUSH ACROSS THE PANHANDLES EARLY NEXT WEEK WITH NO CONVECTION ASSOCIATED WITH THE FRONT. SCHNEIDER FIRE WEATHER... A DEEPENING SURFACE TROUGH OVER EASTERN COLORADO OR WESTERN KANSAS SOUTHWARD TO NEAR THE TEXAS AND NEW MEXICO STATE LINE WILL TRACK EAST INTO THE TEXAS AND OKLAHOMA PANHANDLES ON SUNDAY. INCREASING DOWNSLOPING SOUTHWESTERLY 20 FOOT WINDS AND MINIMUM AFTERNOON HUMIDITIES FALLING INTO THE 15 TO 20 PERCENT RANGE ACROSS MAINLY THE WESTERN SECTIONS OF THE PANHANDLES COULD POSSIBLY RESULT IN ELEVATED FIRE WEATHER CONDITIONS SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING. SCHNEIDER && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 9/98
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1139 AM CDT WED APR 20 2016 .MESOSCALE UPDATE... ...SOME SEVERE WEATHER POSSIBLE TODAY IN MAINLY THE SOUTH CENTRAL AND SOUTHEAST TX PANHANDLE... * SYNOPTIC OVERVIEW: WE`LL SEE ONE LAST GASP SHRTWV TROUGH THIS AFTERNOON FROM THE NOW POSITIVELY TILTED UPR LOW THAT HAS CAUSED WEATHER EXCITEMENT AROUND THE AREA THE PAST 5 DAYS. WATER VAPOR ANALYSIS PLACES THE UPR LOW NEAR NORTH PLATTE, NE THIS MORNING WITH THE LOW EXPECTED TO LIFT TO NEAR OMAHA TONIGHT. THE NW FLOW SHRTWV WILL BEGIN TO IMPACT THE AREA EARLY THIS AFTERNOON, QUICKLY CROSSING THE CWA THIS EVENING. ASCENT FROM THE TROUGH AND ASSOC JET STREAK WILL BE ENOUGH TO SPAWN SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON/EVENING. * MESOSCALE: SHEAR PROFILES WILL BE FAVORABLE FOR ORGANIZED CONVECTION THOUGH SOMEWHAT WEAK INSTABILITY (IE MLCAPE VALUES OF MAYBE 300-600 J/KG) SHOULD KEEP THIS FROM BEING A BARN BURNER OF A DAY. NAM MLCAPE PROGS OF 750-1000 J/KG THIS AFTERNOON JUST EAST OF KAMA SEEM TO BE OVERDONE AS THE NAM HAS OVER-ANALYZED THE AMOUNT OF LOW-LVL MOISTURE DOWNSTATE SO FAR THIS MORNING. DO THINK THAT THE HIGHER SIDE OF RAP/HRRR VALUES OF AROUND 500 J/KG MLCAPE COULD BE REALIZED THOUGH GIVEN THE RAPID REDUCTION OF LOW CLOUD COVER SEEN IN LATEST GOES SUPER RAPID SCAN VIS SAT OBSERVATIONS. * THREATS: THE CAPE DISTRIBUTION LOOKS TO MOST FAVOR ISOLATED DOWNBURST WINDS THIS AFTERNOON GIVEN A SOMEWHAT DEEP/DRY SUBCLOUD LAYER. WITH THE PROPENSITY FOR THE STRONGEST UPDRAFTS TO WANT TO ORGANIZE GIVEN THE FAVORABLE SHEAR PROFILE, SVR HAIL TO THE SIZE OF GOLF BALLS CANNOT BE RULED OUT IN STORMS THAT TAKE ON SUPERCELLULAR CHARACTERISTICS. THE TORNADO WINDOW LOOKS SMALL BOTH SPATIALLY AND TEMPORALLY BUT MAY BRIEFLY EXIST FOR AN HOUR EITHER SIDE OF SUNSET FOR A WEAK ISOLATED TORNADO SOMEWHERE IN THE SE PART OF THE TX PANHANDLE. THE RAPID NW TO SE STORM MOTIONS SHOULD PRECLUDE MUCH OF A FLOOD THREAT TODAY. * TIMING & LOCATION: THE BEST CHANCES FOR SEVERE WEATHER THIS AFTERNOON WILL BE IN THE SOUTH CENTRAL AND SOUTH TX PANHANDLE, THOUGH ISOLATED STRONG TO SEVERE WIND GUSTS COULD OCCUR AS FAR NORTH AS DUMAS OR BORGER. AMARILLO WILL BE ON THE WESTERN EDGE OF THE THREAT, BUT A STRONG OR SEVERE STORM CANNOT BE RULED OUT FOR THE CITY. TIMING-WISE, THE BEST WINDOW WILL PROBABLY BE FROM AROUND 5PM-10PM. SIMPSON/LORENZEN && .PREV DISCUSSION... /ISSUED 648 AM CDT WED APR 20 2016/ AVIATION... MVFR TO IFR CEILINGS EXPECTED TO PERSIST THIS MORNING. LIGHT TO MODERATE SOUTHWEST LOW-LEVEL WINDS EXPECTED TO DEVELOP...BOOSTING DRYING AND DISSIPATION/LIFTING OF LOW CLOUDS. CUMULUS CLOUDS EXPECTED TO DEVELOP THIS AFTERNOON. SCATTERED THUNDERSTORMS EXPECTED TO DEVELOP AFTER 21Z TODAY AS VORTICITY MAXIMUM ARRIVES FROM NORTHWEST. WEAK COLD FRONT WILL SUPPORT THUNDERSTORM DEVELOPMENT THROUGH THE EVENING. DRIER AND MORE STABLE AIR MOVES IN LATE TONIGHT...WITH CLEARING EXPECTED. COCKRELL PREV DISCUSSION... /ISSUED 410 AM CDT WED APR 20 2016/ DISCUSSION... TAKING ANOTHER LOOK AT THE LATEST HIGH-RES MODELS...THE HRRR IS NOW BACKING OFF FROM THE DEVELOPMENT OF DENSE FOG ACROSS THE PANHANDLES THIS MORNING. WILL LIKELY TO NEED TO CANCEL BUT WILL HOLD OFF UNTIL CLOSER TO DAYBREAK TO SEE IF ANY DENSE FOG DEVELOPS. IF NOT...WILL CANCEL BEFORE SHIFT CHANGE THIS MORNING. OTHERWISE...LOW CLOUDS WILL PREVAIL THIS MORNING AS THE VIGOROUS CLOSED UPPER LOW OVER THE CENTRAL PLAINS STATES ALLOWS FOR A VORT LOBE TO ROTATE NORTHWEST TO SOUTHEAST ON THE BASAL OF THE UPPER TROUGH BY 00Z TO 06Z THURSDAY ACROSS THE FORECAST AREA. CONVECTION SHOULD DEVELOP AFTER 20Z TO 22Z TODAY...MAINLY OVER THE SOUTHERN HALF OF THE TEXAS PANHANDLE...WITH THE SEVERE THREAT PRIMARILY ACROSS THE SOUTHEASTERN AND SOUTH CENTRAL PORTIONS OF THE TEXAS PANHANDLE LATER TODAY AND TONIGHT. CONVECTION SHOULD QUICKLY EXIT THE PANHANDLES BY 12Z THURSDAY AS AN UPPER RIDGE BUILDS IN FROM THE WEST LATE THIS WEEK. WARMER AND DRIER CONDITIONS EXPECTED THURSDAY THROUGH THE WEEKEND. THE MEDIUM RANGE MODELS DIFFER WITH RESPECT TO THE NEXT CLOSED UPPER LOW PROGGED TO MOVE OUT OF THE GREAT BASIN REGION THIS WEEKEND INTO EARLY NEXT WEEK. THE ECMWF...WHICH WAS THE DRIER MODEL 24 HOURS AGO...IS NOW FORECASTING AN OPEN WAVE TO TRACK NORTHEAST OUT OF BAJA CALIFORNIA AND NORTHWEST MEXICO FRIDAY NIGHT AND SATURDAY INTO SOUTHWEST TEXAS BY SATURDAY NIGHT AND SUNDAY. THE MAIN CLOSED UPPER LOW IS FORECAST TO LIFT EAST AND NORTH OUT OF THE GREAT BASIN REGION INTO THE CENTRAL ROCKIES AND NORTHERN PLAINS STATES BY EARLY NEXT WEEK. THE ECMWF BREAKS OUT QPF SATURDAY AFTERNOON ACROSS THE NORTHWESTERN PORTIONS OF THE FORECAST AREA SATURDAY AFTERNOON BUT KEEPS THE REMAINDER OF THE WEEKEND AND EARLY NEXT WEEK DRY. THE GFS IS COMPLETELY THE OPPOSITE OF 24 HOURS AGO AND IS NOW KEEPING THE CLOSED UPPER LOW OVER THE NORTHERN STREAM RATHER THAN THE SOUTHERN STREAM. THE GFS ALSO FORECASTS AN OPEN WAVE LIFTING NORTH AND EAST OUT BAJA CALIFORNIA AND NORTHWESTERN/NORTHERN MEXICO...HOWEVER THE GFS KEEPS THE QPF WELL SOUTH OF THE PANHANDLES AND...LIKE THE ECMWF...MAINTAINS A DRY FORECAST THROUGH THE END OF THE WEEKEND INTO EARLY NEXT WEEK. THEREFORE...OPTED TO REMOVE POPS FROM SUNDAY AND GO WITH A DRY AND UNSEASONABLY WARM FORECAST THIS WEEKEND INTO EARLY NEXT WEEK. BREEZY TO WINDY THIS WEEKEND AS A DEEPENING SURFACE TROUGH DEVELOPS TO THE LEE OF THE ROCKIES WHICH WILL THEN TRACK EAST INTO THE FORECAST AREA SUNDAY. A COLD FRONT IS FORECAST TO PUSH ACROSS THE PANHANDLES EARLY NEXT WEEK WITH NO CONVECTION ASSOCIATED WITH THE FRONT. SCHNEIDER FIRE WEATHER... A DEEPENING SURFACE TROUGH OVER EASTERN COLORADO OR WESTERN KANSAS SOUTHWARD TO NEAR THE TEXAS AND NEW MEXICO STATE LINE WILL TRACK EAST INTO THE TEXAS AND OKLAHOMA PANHANDLES ON SUNDAY. INCREASING DOWNSLOPING SOUTHWESTERLY 20 FOOT WINDS AND MINIMUM AFTERNOON HUMIDITIES FALLING INTO THE 15 TO 20 PERCENT RANGE ACROSS MAINLY THE WESTERN SECTIONS OF THE PANHANDLES COULD POSSIBLY RESULT IN ELEVATED FIRE WEATHER CONDITIONS SUNDAY AFTERNOON INTO EARLY SUNDAY EVENING. SCHNEIDER PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 69 45 72 45 77 / 20 50 5 0 5 BEAVER OK 68 44 73 43 79 / 20 20 5 0 5 BOISE CITY OK 65 39 71 41 77 / 30 30 5 0 5 BORGER TX 70 46 75 47 79 / 20 50 5 0 5 BOYS RANCH TX 72 43 74 44 79 / 20 40 5 0 5 CANYON TX 71 44 73 44 77 / 20 40 5 0 0 CLARENDON TX 68 48 73 47 77 / 20 70 10 0 5 DALHART TX 67 41 72 42 77 / 30 40 5 0 5 GUYMON OK 67 42 73 43 79 / 20 20 5 0 5 HEREFORD TX 73 45 73 44 77 / 20 30 5 0 0 LIPSCOMB TX 69 46 74 44 78 / 10 30 5 0 5 PAMPA TX 67 45 70 46 77 / 20 60 10 0 5 SHAMROCK TX 69 49 74 46 78 / 20 70 10 0 5 WELLINGTON TX 70 51 76 47 79 / 20 70 10 0 5 PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 69 45 72 45 77 / 20 50 5 0 5 BEAVER OK 68 44 73 43 79 / 20 20 5 0 5 BOISE CITY OK 65 39 71 41 77 / 30 30 5 0 5 BORGER TX 70 46 75 47 79 / 20 50 5 0 5 BOYS RANCH TX 72 43 74 44 79 / 20 40 5 0 5 CANYON TX 71 44 73 44 77 / 20 40 5 0 0 CLARENDON TX 68 48 73 47 77 / 20 70 10 0 5 DALHART TX 67 41 72 42 77 / 30 40 5 0 5 GUYMON OK 67 42 73 43 79 / 20 20 5 0 5 HEREFORD TX 73 45 73 44 77 / 20 30 5 0 0 LIPSCOMB TX 69 46 74 44 78 / 10 30 5 0 5 PAMPA TX 67 45 70 46 77 / 20 60 10 0 5 SHAMROCK TX 69 49 74 46 78 / 20 70 10 0 5 WELLINGTON TX 70 51 76 47 79 / 20 70 10 0 5 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 9/99